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To evaluate magnesium deficiency during and after acute myocardial infarction (AMI) and the role of intravenous magnesium therapy given in the early postinfarction period. One hundred patients with AMI were randomly assigned to 2 equal groups and monitored over a 4-week period. The placebo group received intravenous dextrose solution and the trial group was given 15 g intravenous magnesium (62 mmol) over a 48-hour period. Serum magnesium levels were measured on days 1, 2, 4, and 6 after admission by calorimetry with methyl thymol blue. The groups were comparable in prevalence of risk factors for coronary artery disease and other acute parameters of AMI. The serum magnesium levels of a group of 50 controls were higher (1.61 +/- 0. 21 vs 1.23 +/- 0.27mEq/L) than in patients with AMI (P <.001). There was an increase in serum magnesium levels in the trial group on day 2 (1.73 +/- 0.27 vs 1.29 +/- 0.28 mEq/L; P <.001) as well as on day 4 (1.62 +/- 0.25 vs 1.38 +/- 0.36 mEq/L; P <.001). The trial group also showed significantly lower incidence of arrhythmias (8% vs 34%) and death (4% vs 20%). The mortality rate from pump failure was reduced in the trial group (4% vs 14%).
Is benefits of magnesium in acute myocardial infarction : timing crucial?
10,740,162
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Considerable interest exists today in biochemical or immunochemical tests for monitoring the progression of osteoarthritis (OA). It has been suggested that measurements made on synovial fluid (SF) will more accurately reflect the magnitude of cartilage destruction in an index joint than those performed on serum. However, we have shown that the synovitis that occurs in OA affects the rate of protein clearance from the joint. We tested the hypothesis that if adjusted for clearance rate, the SF concentration of cartilage proteoglycans (PG) estimates severity of chondropathy and predicts progression of cartilage damage more accurately than if clearance is not taken into account. Clearance of radioiodinated serum albumin (RISA), a surrogate for the clearance of PG, was measured in 19 adult dogs at baseline and again 16 weeks and 32 weeks after anterior cruciate ligament transection (ACLT). Severity of chondropathy was determined arthroscopically after 16 weeks of instability and at postmortem 32 weeks after ACLT. Adjustment for the RISA clearance rate showed that the SF PG concentration markedly underestimated the quantity of PG released from the OA cartilage. Regardless of whether the concentration was adjusted for clearance, no correlation existed between the SF PG level and the severity of chondropathy. Further, the SF concentration of PG 16 weeks after ACLT failed to predict severity of cartilage damage at postmortem.
Does synovial fluid glycosaminoglycan concentration correlate with severity of chondropathy or predict progression of osteoarthritis in a canine cruciate deficiency model?
10,743,821
{ "answer_start": [ 57 ], "text": [ "no" ] }
Prepubertal children and early adolescents with bipolar disorders (PEA-BP) who participate in the ongoing study "Phenomenology and Course of Pediatric Bipolar Disorders" have a high prevalence of ultradian (within 24-hour periods) rapid cycling. Based on a case-control finding reported in bipolar (BP) adults of an association between rapid and ultradian rapid cycling with the low-activity allele of catechol-O-methyltransferase (l-COMT), study of linkage and linkage disequilibrium of l-COMT in the PEA-BP population seemed warranted. Genotypes on a subset of the larger PEA-BP sample, for whom trio blood collection was complete (i. e., probands and both of their biological parents), were used to perform transmission disequilibrium tests (TDTs). Diagnoses were established from a comprehensive battery that included WASH-U-KSADS (Washington University Kiddie Schedule for Affective Disorders and Schizophrenia) given to both mothers and children and from consensus conferences. Probands with PEA-BP (N = 52) were 10.9 +/- 2.8 years old at index episode; had a mean age of BP onset at 8.0 +/- 3.8 years; were severely impaired, with a mean Children's Global Assessment Scale score of 44.5 +/- 8.9; and manifested the cardinal features of BP (84.6% had euphoric mood, 76.9% had grandiosity, and 57.7% had psychosis). Ultradian rapid cycling occurred in 75%. Genotyping of the single nucleotide polymorphism at COMT was performed using automated capillary electrophoresis single-strand conformational polymorphism with detection by laser-induced fluorescence. Transmission disequilibrium tests were not significant for preferential transmission of l-COMT for the ultradian rapid-cycling subgroup or for the entire PEA-BP sample.
Is ultradian rapid cycling in prepubertal and early adolescent bipolarity in transmission disequilibrium with val/met COMT alleles?
10,745,052
{ "answer_start": [ 116 ], "text": [ "no" ] }
To test whether extension of the C-terminus of human chorionic gonadotropin (hCG) alpha-subunit (halpha) alters the bioactivity of the recombined alphabeta heterodimer. The stop codon of halpha was mutated to produce a 24 amino acid extension. The extended halpha (alpha(+24)) was co-expressed with hCGbeta in COS-7 cells and the receptor binding and in vivo bioactivity of the secreted hormone was compared with its wild-type counterpart. This extension did not impair the binding of hCG to rat LH/CG receptors and provoked a sixfold reduction in its stimulatory activity of testosterone secretion in rat Leydig cells.
Does human chorionic gonadotropin with C-elongated alpha-subunit retain full receptor binding and partial agonist activity?
10,754,483
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Mycophenolate mofetil (MMF) is an effective immunosuppressant developed for use in organ transplantation. It specifically targets lymphocyte purine biosynthesis. However, side effects do occur. Understanding how the active metabolite of MMF, mycophenolic acid (MPA) affects the normally integrated interaction between intracellular purine and pyrimidine pathways might aid the development of improved therapeutic regimes. We used a primary human T-lymphocyte model to study how preincubation with MPA (0.1-50 microM) affected normal ribonucleotide pool responses to phytohemagglutinin using radiolabeled precursors. MPA not only restricted the mitogen-induced expansion of GTP pools, but actually induced a severe drop in both GTP (10% of unstimulated cells) and GDP-sugar pools, with a concomitant fall in ATP (up to 50%). These effects were concentration dependent. By contrast, uridine pools expanded whereas CTP pools remained at resting levels. These changes were confirmed by the altered incorporation of [14C]-bicarbonate and [14C]-glycine into nucleotides. Restriction of [14C]-hypoxanthine incorporation and reduction of [14C]-uridine uptake comparable to that of unstimulated cells indicated that MPA also inhibited both salvage routes of nucleotide synthesis.
Does mycophenolic acid-induced GTP depletion also affect ATP and pyrimidine synthesis in mitogen-stimulated primary human T-lymphocytes?
10,755,546
{ "answer_start": [ -1 ], "text": [ "yes" ] }
It has been reported that T-cell depletion by in vivo treatment with monoclonal antibodies results in polyclonal B-cell activation. However, its effects on B cells responding to Galalpha1,3Gal (Gal) epitopes remain unknown. alpha1,3-Galactosyltransferase-deficient (GalT-/-) mice were treated with depleting anti-CD4 and CD8 monoclonal antibodies. The kinetics of anti-Gal natural antibodies (NAb) and total immunoglobulin levels in their sera were evaluated. The frequencies of anti-Gal NAb-producing cells were determined in the various tissues of GalT-/- mice by enzyme-linked immunospot assay. In vivo T-cell depletion led to significant increases in both anti-Gal IgM and total IgM levels in sera of GalT-/- mice, but did not influence either anti-Gal IgG or total IgG levels. An increased frequency of anti-Gal and total IgM-producing cells was observed in the spleens and bone marrow of T-cell-depleted GalT-/-mice but not in peritoneal cavity cells.
Does in vivo T-cell depletion enhance production of anti-GALalpha1,3GAL natural antibodies in alpha1,3-galactosyltransferase-deficient mice?
10,755,549
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To determine the role of lymphocyte proliferation assay of synovial fluid mononuclear cells (SFMC) with whole fraction bacteria in the diagnosis of reactive arthritis (ReA) or arthritis of unknown origin. We stimulated SFMC of 52 unselected patients who consecutively presented in our rheumatology outpatient clinic with the following diagnoses: ReA (n = 8), rheumatoid arthritis (RA) (n = 16), ankylosing spondylitis (AS) (n = 6), osteoarthritis (OA) (n = 5), psoriatic arthritis (PsA) (n = 5) and arthritis of varying origin (AVO) (n = 12) and peripheral blood MC (PBMC) of 10 healthy controls with arthritogenic (Y. entero-colitica, S. enteritidis, C. trachomatis) and non-arthritogenic (E. coli, K. pneumoniae, S. pyogenes, C. albicans) bacteria/mitogens and Tetanus toxoid. T cell proliferation was measured in a standard [3H] Thymidine uptake assay. In all groups of patients tested, SFMC could be stimulated both by arthritogenic and non-arthritogenic bacteria. So-called specific responses were observed in patients with ReA, but also in RA and AS.
Is synovial fluid lymphocyte proliferation in response to crude microbial antigens useful as a diagnostic test to specifically indicate a bacterial cause of arthritis?
10,728,442
{ "answer_start": [ 61 ], "text": [ "no" ] }
White cell reduction of blood products minimizes the risks of alloimmunization against HLA-antigens, the transmission of viral diseases and the incidence of platelet transfusion reactions. One modern strategy is leukocyte depletion with an integrated filter system immediately after preparation and prior to storage. We evaluated the efficiency of a novel in-line filter system Sepacell PLX-5 BPS for leukocyte reduction of platelet concentrates (PC) from pooled buffy-coats. A total of 44 PCs were investigated with regard to different filtration flow rates (25-110 ml/min) and leukocyte depletion and thrombocyte recovery rates were analysed. Furthermore, we studied the influence of filtration on PCs over a storage period of 6 days (n = 12) by investigation of pH, lactate and glucose. Platelet function was determined by means of hypotonic shock response, external shape change and expression of CD62p. The mean leukocyte depletion rate was > log 5. After filtration the mean leukocyte count was 0.12 +/- 0.21 x 10(6). In 60% of the PCs the leukocyte count lay below the detection level of the Nageotte chamber, which is < 0.3 x 10(5). The flow rate correlates significantly with the leukocyte count in the PCs (r = 0.325; p = 0.033) and therefore with the leukocyte depletion rate (r = -0.422; p = 0.01). Flow rates under 40 ml lead to a significantly lower leukocyte contamination. Only in one PC, at a flow rate of 84 ml/min, was the leukocyte threshold of 1 x 10(6) exceeded. We did not find a significant correlation between filtration flow rate and thrombocyte recovery (r = 0.315; p = 0.069). The mean platelet count in the PC was 2.88 +/- 0.47 x 10(11). Compared with the thrombocyte count in the pooled buffy coat, the recovery was 68.6%. We observed a decrease of pH, glucose, external shape change and hypotonic shock response over the storage period while lactate and the expression of CD62p increased.
Does the flow rate significantly influence the leukocyte depletion rate during prestorage in-line filtration of platelet concentrates?
10,747,520
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The number of positive axillary lymph nodes predicts prognosis and is often important in determining adjuvant chemotherapy in breast cancer patients. This study was undertaken to determine if differences in the extent of axillary node dissection would alter the number of reported positive nodes. The study population consisted of 302 patients with invasive breast cancer who underwent complete (level I/II/III) axillary lymph node dissection. Assuming that all patients had undergone a level I/II dissection, it was determined how frequently a patient's nodal category (0, 1-3, 4-9, >10 positive nodes) would have been altered if a level I or level I/II/III dissection were performed. Assuming that all 302 patients had undergone a level I/II dissection, performing only level I dissection would have resulted in a change in nodal category in 15.9% of all patients and 36.1% of patients with positive nodes. The corresponding changes for a level I/II/III dissection would have been 4.3% and 9.5%, respectively.
Does variation in axillary node dissection influence the degree of nodal involvement in breast cancer patients?
10,738,265
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Hypertrophic cardiomyopathy is a myocardial disorder resulting from inherited sarcomeric dysfunction. We report a mutation in the myosin-binding protein-C (MyBP-C) gene, its clinical consequences in a large family, and myocardial tissue findings that may provide insight into the mechanism of disease. History and clinical status (examination, ECG, and echocardiography) were assessed in 49 members of a multigeneration family. Linkage analysis implicated the MyBP-C gene on chromosome 11. Myocardial mRNA, genomic MyBP-C DNA, and the myocardial proteins of patients and healthy relatives were analyzed. A single guanine nucleotide insertion in exon 25 of the MyBP-C gene resulted in the loss of 40 bases in abnormally processed mRNA. A 30-kDa truncation at the C-terminus of the protein was predicted, but a polypeptide of the expected size ( approximately 95 kDa) was not detected by immunoblot testing. The disease phenotype in this family was characterized in detail: only 10 of 27 gene carriers fulfilled diagnostic criteria. Five carriers showed borderline hypertrophic cardiomyopathy, and 12 carriers were asymptomatic, with normal ECG and echocardiograms. The age of onset in symptomatic patients was late (29 to 68 years). In 2 patients, outflow obstruction required surgery. Two family members experienced premature sudden cardiac death, but survival at 50 years was 95%.
Is a newly created splice donor site in exon 25 of the MyBP-C gene responsible for inherited hypertrophic cardiomyopathy with incomplete disease penetrance?
10,736,283
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Unintentional injuries are the leading cause of death in children, and falls are the most common type of unintentional injury in the US. The incidence of falls from windows, a common cause of death in urban areas, has not been described outside major cities such as New York and Chicago, and rates in urban and suburban areas have not been compared. To estimate the incidence and identify the population at risk for falls from windows among children in Hamilton County, Ohio. Retrospective case series identified using Cincinnati Children's Hospital Medical Center (CHMC) Trauma Registry. Hamilton County, Ohio, which has urban and nonurban areas. Children less than 15 years old residing in Hamilton County, Ohio, presenting to CHMC in Cincinnati, Ohio, after a fall from a window between January 1, 1991, and December 31, 1997. Annual incidence by age, race, gender, and residence of those who fell from windows. Over the 7-year study period, 86 (6.3%) of 1,363 falls were from windows. The mortality rate for falls from windows was 4.7%, compared to 0.07% for all other falls presenting to CHMC (P<.0001). Children 0-4 years old had a higher rate of falls than children aged 5-14 (14.6/100,000 vs. 2.0/100,000) (P<.0001). Males were twice as likely to fall as females (P<.016), and black children were three times more likely to fall than non-black children (P<.002). The incidence of falls in the city of Cincinnati was four times that of the non-urban area (P<.0002).
Does childhood injuries and deaths due to fall from windows?
10,741,840
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Hypoxemia is a common complication of chronic obstructive pulmonary disease and a major factor in patients' prognosis and quality of life. The response to exercise has been evaluated by various means but no standardization has been accepted. To suggest a simple outpatient technique for evaluating the response of arterial oxygen saturation to exercise for use as a marker of disease severity. Ninety-six patients with various degrees of COPD were divided into three groups: mild (forced expiratory volume in 1 sec > 65%), moderate (FEV1 between 50 and 65%), and severe (FEV1 < 50%). Using continuous oximeter recording we measured oxygen saturation during 15 steps of climbing, and quantified oxygen desaturation by measuring the "desaturation area," defined as the area under the curve of oxygen saturation from the beginning of exercise through the lowest desaturation point and until after recovery to the baseline level of oxygen percent saturation. Desaturation was correlated to spirometry, lung gas volumes, blood gas analysis, and 6 min walking distance. A good correlation was found between severity of COPD and baseline SaO2, lowest SaO2, recovery time, and desaturation area. A negative correlation was found between desaturation area and FEV1 (r = -0.65), FEV1/forced vital capacity (r = -0.58), residual volume to total lung capacity (r = 0.52), and diffusing lung capacity for carbon monoxide (r = -0.52). In stepwise multiple regression analysis only FEV1 correlated significantly to desaturation area. A good correlation was noted between 6 min walking distance and desaturation area with the 15 steps technique (r = 0.56).
Do quantitative 15 steps exercise oximetry as a marker of disease severity in patients with chronic obstructive pulmonary disease?
10,731,326
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Both in experimental colitis and in inflammatory bowel disease, colonic eicosanoid generation is enhanced and may contribute to the pathogenesis of the inflammatory response. To evaluate the effect of selective cyclo-oxygenase-2 (COX-2) inhibitors on the extent and severity of two models of experimental colitis. Colitis was induced by intra-caecal administration of 2 ml 5% acetic acid or intra-colonic administration of 0.1 ml 3% iodoacetamide. Rats were treated intra-gastrically with nimesulide 2 x 10 mg/kg/day, or once with SC-236 6 mg/kg, and killed 1 or 3 days after damage induction. The colon was isolated, weighed, macroscopic damage was measured, and mucosal samples were obtained for histology and for determination of myeloperoxidase (MPO) and nitric oxide synthase (NOS) activities and eicosanoid generation. The serum levels of thromboxane B2 (TXB2), tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) were determined. Nimesulide significantly decreased the extent of colitis induced by acetic acid. Both nimesulide and SC-236 significantly decreased the extent of iodoacetamide-induced colonic damage. The decrease in the extent of colitis induced by nimesulide was accompanied by a significant decrease in mucosal MPO and NOS activities. Nimesulide and SC-236 decreased the enhanced colonic eicosanoid generation in acetic acid and iodoacetamide-induced colitis, and, in iodoacetamide-treated rats, nimesulide also decreased the elevated serum TNF-alpha and IL-1beta levels.
Do cyclo-oxygenase-2 inhibitors ameliorate the severity of experimental colitis in rats?
10,741,939
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Although the majority of evidence does not support association between Helicobacter pylori infection and ischaemic heart disease, the nature of this relationship may differ when virulence of the infecting strains are examined. The prevalence of IgG antibody evidence of infection with CagA positive stains of H. pylori was investigated in stored plasma samples from 259 cases of myocardial infarction (aged 25-70 years, 74 males) and 259 population based controls from the same area in Northern Ireland. Two-hundred and seventy (52.1%) subjects were seropositive for anti-CagA IgG. CagA seropositivity was more common in cases than in controls: 56.4 vs 47.9%, odds ratio for seropositivity in cases (95% CI) 1.41 (1.00, 1.99). Substantial attenuation of this relationship occurred on adjustment for age, sex, number of siblings, smoking and measures of socio-economic status: odds ratio (95% CI) 1.16 (0.79, 1.70). A similar pattern was seen for seropositivity for all H. pylori strains.
Is infection with virulent strains of Helicobacter pylori associated with ischaemic heart disease : evidence from a population-based case-control study of myocardial infarction?
10,729,388
{ "answer_start": [ 39 ], "text": [ "no" ] }
The potential to modulate the inflammatory response has renewed interest in hypertonic saline (HTS) resuscitation of injured patients. However, the effect of the timing of HTS treatment with respect to polymorphonuclear neutrophil (PMN) priming and activation remains unexplored. We hypothesized that HTS attenuation of PMN functions requires HTS exposure before priming and activation. Isolated PMN were incubated in HTS (180 mM Na+) before L-alpha-phosphatidylcholine, beta-acetyl-gamma-O-alkyl (PAF)/N-formylmethionyl-leucyl-phenylalanine (fMLP) priming/activation, after priming, or after priming/activation. Superoxide production was measured by the reduction cytochrome c, elastase release by cleavage of AAPV-pNA, and beta2-integrin expression by flow cytometry. HTS before priming or activation decreased beta2-integrin expression, superoxide production, and elastase release. In contrast, HTS after priming/activation augmented superoxide production and elastase release.
Is hypertonic saline attenuation of polymorphonuclear neutrophil cytotoxicity : timing everything?
10,744,274
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To determine whether early enteral feeding in a septic intensive care unit (ICU) population, using a formula supplemented with arginine, mRNA, and omega-3 fatty acids from fish oil (Impact), improves clinical outcomes, when compared with a common use, high protein enteral feed without these nutrients. A prospective, randomized, multicentered trial. ICUs of six hospitals in Spain. One hundred eighty-one septic patients (122 males, 59 females) presenting for enteral nutrition in an ICU. Septic ICU patients with Acute Physiology and Chronic Health Evaluation (APACHE) II scores of > or =10 received either an enteral feed enriched with arginine, mRNA, and omega-3 fatty acids from fish oil (Impact), or a common use, high protein control feed (Precitene Hiperproteico). One hundred seventy-six (89 Impact patients, 87 control subjects) were eligible for intention-to-treat analysis. The mortality rate was reduced for the treatment group compared with the control group (17 of 89 vs. 28 of 87; p < .05). Bacteremias were reduced in the treatment group (7 of 89 vs. 19 of 87; p = .01) as well as the number of patients with more than one nosocomial infection (5 of 89 vs. 17 of 87; p = .01). The benefit in mortality rate for the treatment group was more pronounced for patients with APACHE II scores between 10 and 15 (1 of 26 vs. 8 of 29; p = .02).
Does an immune-enhancing enteral diet reduce mortality rate and episodes of bacteremia in septic intensive care unit patients?
10,752,808
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Are the results of cemented titanium hip arthroplasty as bad as described in literature? We present the 10-year results of a cemented mild grid blasted Titanium-Aluminium-Vanadium Stem in Total-Hip-Arthroplasty. The clinical and radiological reexamination was documented in standardized questionnaire in which several scores were integrated. All X-rays were stored and analysed by a special hardware and software computer system. 35% of all patients could be reexamined both clinically and roentgenologically. 71 patients were male (mean age 56.1 years) and 130 female (mean age 59.3 years). The average follow-up period was 11 years and 4 months. The mean Merle d'Aubigné hip score increased from 10.5 to 16.0 points at the follow-up evaluation. Radiolucent lines were according to the zones of Gruen seen in 1% to 22% depending on the zone and the size of the femoral component. 18 reoperations of the femoral component (2.9%) had to be performed. The survivorship analysis (Kaplan-Meier) showed a 95.4% survival of the femoral component after 10 years.
Does [ 10 year result with a cemented fine-grit-blasted titanium-aluminum-vanadium hip endoprosthesis shaft ]?
10,730,364
{ "answer_start": [ -1 ], "text": [ "yes" ] }
An early sign of apoptosis in many cells is the appearance of phosphatidylserine (PS) on the outside of the plasma membrane, whilst the cells still retain the ability to exclude DNA-binding molecules such as propidium iodide and 7-aminoactinomycin D (7-AAD). The protein annexin V binds preferentially to PS and has often been used to monitor the early phase of apoptosis. There have been some conflicting results concerning whether annexin V binds to camptothecin (CAM)-treated HL-60 cells, a commonly used model for apoptosis. We investigated the effects of culturing HL-60 cells for up to 8 h with a range of CAM concentrations. We used flow cytometry to measure cellular light scatter, annexin V-FITC binding, and 7-AAD uptake, and DNA content after fixation and permeabilization. We also used microscopy to examine the morphology of cells (both unsorted and sorted according to their light scatter) after cytocentrifugation. We found that CAM caused the rapid appearance of low light scatter apoptotic bodies. Even among cells with "normal" light scatter, there was widespread DNA cleavage and nuclear fragmentation by 3 h. The percentage of apoptotic bodies peaked at about 4 h and it was only afterward that annexin V binding could be detected to both intact cells and to apoptotic bodies. When they first appeared, the intact annexin V+ cells had S-phase DNA content.
Is there substantial nuclear and cellular disintegration before detectable phosphatidylserine exposure during the camptothecin-induced apoptosis of HL-60 cells?
10,754,512
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The transcription factor nuclear factor-kappaB (NF-kappaB) plays a central role in regulating immune and inflammatory responses. Because butyrate deficiency has been associated with inflammatory bowel disease, we examined the effect of butyrate on NF-kappaB activity in the human HT-29 colonic cell line. The influence of butyrate (4 mmol/L) on NF-kappaB activity was determined using the gel mobility shift assay. The effect of butyrate on the expression of NF-kappaB subunits and inhibitory proteins was determined by immunoblotting. NF-kappaB-regulated gene expression was assayed by primer extension of intercellular adhesion molecule 1 and Mn superoxide dismutase messenger RNA, and by analysis of a transfected luciferase reporter. Exposure of HT-29 cells to butyrate eliminated their constitutive NF-kappaB, p50 dimer activity. This inhibition corresponded with a reduction in p50 nuclear localization, without a reduction in expression. Butyrate also selectively modulated activation of NF-kappaB, suppressing its activation by tumor necrosis factor alpha and phorbol ester more than 10-fold, without affecting the activity induced by interleukin (IL)-1beta. Butyrate did, however, enhance formation of the stronger p65-p50 transcriptional activator in IL-1beta-stimulated cells. The changes in NF-kappaB activation did not correlate with changes in IkappaBalpha levels. Gene expression reflected DNA binding. The influence of butyrate on NF-kappaB may result in part from its ability to inhibit deacetylases because the specific deacetylase inhibitor trichostatin A has a similar effect.
Does the luminal short-chain fatty acid butyrate modulate NF-kappaB activity in a human colonic epithelial cell line?
10,734,024
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Parenteral control of gastric acid hypersecretion in conditions such as Zollinger-Ellison syndrome (ZES) or idiopathic gastric acid hypersecretion is necessary perioperatively or when oral medications cannot be taken for other reasons (e.g., during chemotherapy, acute upper gastrointestinal bleeding, or in intensive care unit settings). We evaluated the efficacy and safety of 15-minute infusions of the proton pump inhibitor pantoprazole (80-120 mg every 8-12 hours) in controlling acid output for up to 7 days. Effective control was defined as acid output >10 milliequivalents per hour (mEq/h) (<5 mEq/h in patients with prior acid-reducing surgery) for 24 hours. The 21 patients enrolled had a mean age of 51.9 years (range, 29-75) and a mean disease duration of 8.1 years (range, <0.5-21); 13 were male, 7 had multiple endocrine neoplasia syndrome type I, 4 had undergone acid-reducing surgery, 2 had received chemotherapy, and 13 had undergone gastrinoma resections without cure. Basal acid output (mean +/- SD) was 40.2 +/- 27.9 mEq/h (range, 11.2-117.9). In all patients, acid output was controlled within the first hour (mean onset of effective control, 41 minutes) after an initial 80-mg intravenous pantoprazole dose. Pantoprazole, 80 mg every 12 hours, was effective in 17 of 21 patients (81%) for up to 7 days. Four patients required upward dose titration, 2 required 120 mg pantoprazole every 12 hours, and 2 required 80 mg every 8 hours. At study end, acid output remained controlled for 6 hours beyond the next expected dose in 71% of patients (n = 15); mean acid output increased to 4.0 mEq/h (range, 0-9.7). No serious or unexpected adverse events were observed.
Does intravenous pantoprazole rapidly control gastric acid hypersecretion in patients with Zollinger-Ellison syndrome?
10,734,021
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Analogous to vascular endothelium, bronchial epithelium modulates bronchomotor activity by releasing epithelium-derived relaxing factors. Cardiopulmonary bypass (CPB) is associated with endothelial dysfunction. We examined whether CPB may be associated with bronchiolar epithelial dysfunction in pigs. Pigs were exposed to normothermic CPB for 1.5 h and then separated from CPB. Lung tissues were biopsied before and 30 min after CPB. For time control, lung tissues were biopsied at baseline and after 2 hr of anesthesia. Bronchioles measuring about 100 microm were dissected, and the epithelium was either left intact or denuded. Each bronchiolar segment was preconstricted with 10 microM 5-hydroxytryptamine and relaxation responses to nitroprusside 10(-9)-10(-4) M, isoproterenol 10(-9)-10(-4) M, or the inhaled anesthetics halothane or isoflurane 0-2.5 minimum alveolar anesthetic concentration were examined in vitro by videomicroscopy. Bronchiolar segments demonstrated concentration-dependent relaxation responses to each of the dilators examined. Epithelial denudation reduced bronchodilation to isoproterenol, isoflurane, and halothane, but not to nitroprusside. Bronchodilation was not significantly affected by CPB. We conclude that, unlike vascular endothelial function, porcine bronchiolar epithelium-modulated bronchomotor activity is not significantly affected by normothermic CPB.
Is epithelium-dependent bronchodilatory activity preserved in pig bronchioles after normothermic cardiopulmonary bypass?
10,735,775
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Mark/recapture (or capture-recapture) is a simple technique commonly applied to estimate the hypothetical total (including undercount) in a register composed of cases from two or more independent and separately incomplete case lists. This paper seeks to illustrate serious drawbacks in the use of the mark/recapture technique when applied to injuries. Northumbrian children under 15 years of age who were seriously injured in motor vehicle accidents (MVAs) over a five year period ascertained from two data sources: police reports and hospital inpatient records. Individuals (n) appearing in both police (S) and hospital (H) case lists are identified using various matching criteria. The separate and combined influence of age, sex, and casualty class (cyclist, passengers, pedestrians) on the probability of such matching is estimated using multivariate techniques. The hypothetical total incidence of child MVA victims (N) is calculated from N = (S x H)/n. Estimates of the incidences of "serious" injuries in MVAs under various conditions of stratification and matching. The overall procedure is tested for conformity with accepted criteria for valid use of mark/recapture. About one third of the 1009 police and 836 hospital records could be exactly matched. There were significant variations in matching proportions by class of accident (pedestrian v passenger v cyclist). This selective recapture or "heterogeneity" was not affected by sex, but was independently influenced by the age of the child. Further uncertainty was introduced when matching criteria were slightly relaxed. Estimates of the total population of children with serious injuries vary accordingly from 1729 to 2743. A number of plausible reasons why these two data sources might not be unbiased or mutually independent samples of the total target population are proposed as explanations for this heterogeneity.
Are children goldfish -- mark/recapture techniques and their application to injury data?
10,728,542
{ "answer_start": [ 1426 ], "text": [ "no" ] }
The purpose of this study was to compare the arterial response following implantation of a stainless-steel, balloon-expandable, tubular slotted stent with that of a novel computer-designed, multi-cellular stent in normal porcine coronary arteries. Intracoronary stent placement has evolved into the primary strategy for percutaneous revascularization of symptomatic coronary arterial lesions. Presently there is intense interest in developing new stent designs to improve stent delivery and biocompatability. Computer-assisted design was utilized to develop a balloon-expandable stent with symmetric expansion properties, uniform arterial wall coverage, longitudinal flexibility and radial strength. Quantitative coronary angiography and histological assessment of the stented arteries was used to evaluate the acute and chronic vascular responses to a stainless-steel, balloon-expandable, tubular slotted stent as compared to the computer-designed BX stent in the normolipemic swine. Forty stents (24 BX, 16 tubular slotted) were implanted in 19 miniature swine at a mean inflation pressure of 9 atm using identical delivery systems. Eight of the BX and none of the tubular slotted stents were post-dilated with a non-compliant balloon at 12-14 atm. The mean stent-to-artery ratio was similar for the BX (1.03 +/- 0.06) and tubular slotted (1.04 +/- 0.11; p = 0.59) designs. Protrusion or asymmetric radial flaring of a strut at the stent margin was present in 1 of 23 BX stents (4.3%) and 10 of 15 tubular slotted stents (66.7%; p < 0.0001). The mean arterial injury score was significantly less for the BX stent (0.2 +/- 0.2) as compared with the tubular slotted stents (0.4 +/- 0.4; p = 0.025). At 3 days, thrombus area was similar for the BX and tubular slotted designs (0.42 +/- 0.16 mm2 versus 0.44 +/- 0.18 mm2, respectively; p = 0.88). The mean neointimal area was significantly less for the BX at 2 months (1.09 +/- 0.25 mm2 versus 2.93 +/- 2.26 mm2 in the tubular slotted stent) and at 6 months (1.10 +/- 0.26 mm2 versus 2.07 +/- 0.65 mm2 in the tubular slotted stent; p = 0.01), resulting in approximately 50% less in-stent stenosis.
Does stent design favorably influence the vascular response in normal porcine coronary arteries?
10,745,499
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The stress electrocardiogram (sECG) is routinely used to screen individuals for underlying cardiac pathology before an exercise programme is prescribed. The underlying assumption is that the cardiac responses elicited during the sECG test are similar to those achieved during participation in sporting activities. However, this premise may be incorrect since the physical demands of different modes of exercise vary substantially. Ten veteran league squash players (LSP), 10 social squash players (SSP), 10 league runners (LR), 10 social runners (SR) and 10 sedentary individuals (SED) were recruited for the study. All subjects completed a lifestyle questionnaire, a full medical examination and a routine sECG. Thereafter each subject's heart rate (HR) was monitored on two separate occasions while participating in sporting activity. No sECG exercise-induced abnormalities were observed, although five subjects showed resting abnormalities. Maximal HR during the sECG, and maximal and mean HR during the field tests, were not significantly different between groups. However, maximal HR was significantly higher in all groups during their sporting activities than during stress testing in the laboratory (P < 0.01).
Do veteran athletes exercise at higher maximum heart rates than are achieved during standard exercise ( stress ) testing?
10,745,968
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Lymphopenia has been described in patients with chronic renal failure (CRF). It is postulated that the decline in lymphocytes is due to accelerated apoptosis. We investigated whether dysregulation of programmed cell death plays a role in the immunodeficiency described in CRF. Peripheral blood lymphocytes (PBL) from pre-dialysis uraemic patients (nHD) and haemodialysed patients (HD) were cultured with no stimulus for 96 h. Apoptosis of lymphocytes was measured by propidium iodide staining and flow cytometry. Expression of Fas and Bcl-2 was also analysed by flow cytometry. Peripheral blood B cells were significantly lower in pre-dialysis and haemodialysis uraemic patients compared to control. Lymphocytes from both groups of patients had a higher rate of apoptosis in vitro than those from healthy controls. This effect was more pronounced in B lymphocytes and a significant correlation between the B lymphopenia and the percentage of apoptotic B cells after 48 h of culture without stimulus was observed. The increased lymphocyte apoptosis in CRF was accompanied by a significantly lower in vitro Bcl-2 expression. However, Fas did not seem to play a role in spontaneous lymphocyte apoptosis in end-stage renal disease.
Is b lymphopenia in uremia related to an accelerated in vitro apoptosis and dysregulation of Bcl-2?
10,727,545
{ "answer_start": [ -1 ], "text": [ "yes" ] }
During real-time monitoring of the ultrafiltration coefficient (Kuf) in haemodiafiltration (HDF), it was noticed that the ultrafiltration performance of polysulphone membrane dialysers increased when hypertonic glucose (D50%) was administered through the venous blood return. This observation was explored in six non-diabetic chronic dialysis patients during 48 HDF sessions using 1.8 m(2) polysulphone membrane dialysers. In all six patients, 24 sessions were performed with glucose supplementation (as a continuous D50% (500 g/l) infusion at 40 ml/h) and 24 sessions without supplementation. Glucose supplementation led to a marked increase in Kuf from 22.8+/-2.2 (without D50%, n=24) to 32. 1+/-3.9 ml/h/mmHg (with D50%, n=24) (P<0.0001). An increase in percentage reduction ratios for urea and creatinine were also consistently observed during the sessions with glucose administration (from respective mean values of 75+/-5 and 68+/-4% to 79+/-4 and 74+/-10%). Mean double-pool Kt/V, calculated from serum urea concentrations, rose from 1.65+/-0.24 (n=24) to 1.86+/-0.24 (n=24) (P<0.005). Similar results were observed in a subgroup of 18 HDF sessions (nine with glucose and nine without) monitored with an on-line urea sensor of spent dialysate. No detrimental effects were induced at any time.
Does intradialytic glucose infusion increase polysulphone membrane permeability and post-dilutional haemodiafiltration performances?
10,727,546
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Smooth muscle cell (SMC) migration and proliferation are the key steps in the development of atherosclerosis and restenosis. Matricellular proteins have been implicated in cell adhesion, migration and proliferation. Here we investigated the role of the matricellular protein galectin-1 (Gal-1), a beta-galactoside-binding lectin, in SMC proliferation in atheroma and DNA synthesis in cell culture. Protein expression was visualised by tissue section immunostaining. RNA expression was analysed using Northern blot analysis. DNA synthesis of human vascular SMCs was determined by 3H-thymidine incorporation. Recombinant glutathione S-transferase-galectin-1 fusion protein (Gal FP) binding to extracellular matrix (ECM) proteins was measured by ELISA. Gal-1 binding to cells and ECM was estimated using 125I-labelled Gal FP. Prominent Gal-1 staining coincided with SMC proliferation in human coronary endarterectomy samples in organoid culture. In cell culture, Gal-1 mRNA was upregulated in growing SMCs. Gal FP increased serum-induced DNA synthesis of human SMCs on plastic or endogenous ECM, but not of a rat PAC1 SM cell line. Also, Gal FP slightly increased SMC adhesion to ECM. SMCs exhibited a complex pattern of receptor-ligand interactions with Gal FP. The Gal-1 binding to SMCs was much stronger than to ECM, produced by these SMCs. We identified new ECM proteins: thrombospondin, vitronectin and osteopontin, which bound to Gal FP in a dose- and beta-galactoside-dependent manner in ELISA.
Is galectin 1 involved in vascular smooth muscle cell proliferation?
10,728,371
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Enterovirus infections are major etiological factors in myocarditis and dilated cardiomyopathy. Using an experimental murine model of this disease, previous studies have shown that myocarditis susceptibility depends upon activation of T lymphocytes expressing the gamma delta T cell receptor (TcR), and that only mouse strains which accumulate gamma delta T cells in the myocardium show apoptosis of myocytes or evidence of dilated cardiomyopathy-like disease. The objective of the present studies is to demonstrate that gamma delta T cells directly induce greater Fas-dependent apoptosis of cultured myocytes than T cells expressing the alpha beta TcR. Bl.Tg.E alpha mice were infected for 7 days with coxsackievirus B3 (CVB3). Hearts were removed and were either formalin-fixed, sectioned and stained with hematoxylin and eosin for inflammation, and using TdT-TUNEL for apoptosis, or were minced and collagenase digested for isolation of gamma delta+ and alpha beta+ T cells using immunomagnetic bead separation. Neonatal cultures of cardiac myocytes were isolated from mice less than 2 days old by collagenase and pancreatin digestion, and were either untreated or infected with virus. Levels of Fas (CD95) were measured using FITC-conjugated hamster anti-mouse Fas monoclonal antibody and flow cytometry. Susceptibility of myocytes to Fas-dependent killing was measured by 51Cr-release by labeled myocytes incubated for 4 h on either 3T3-mock or 3T3-FasL transfected cell monolayers. Killing by T cells was also measured in a 4 h 51Cr-release assay. Fas-dependent and perforin-dependent cytotoxicity was determined by specific blocking using either Fas-Fc or concanamycin A. Virally infected myocyte cultures showed significantly enhanced Fas expression compared to uninfected cells, with maximal upregulation of Fas occurring 18-24 h after virus infection. Both infected and uninfected myocytes were selectively killed by FasL-transfected 3T3 cells but not by mock control cells. Approximately 38% of CD3+ lymphocytes isolated from the heart express the gamma delta TcR with the remainder expressing the alpha beta TcR. Both gamma delta+ and alpha beta+ T cells lysed myocyte targets. Blocking studies indicate that gamma delta+ T cells induced predominantly Fas-mediated killing, while alpha beta+ cell produced more perforin-mediated death, although these effectors were capable of Fas-dependent killing as well.
Do t cells expressing the gamma delta T cell receptor induce apoptosis in cardiac myocytes?
10,728,379
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The Boston HAPPENS (HIV Adolescent Provider and Peer Education Network for Services) program is a collaborative network of care made up of 8 organizations that serve youth and provide coordinated care for human immunodeficiency virus (HIV)-positive, homeless, and at-risk youth aged 12 to 24 years. Learning youth perceptions about the program is essential to determine if the program is meeting their needs. In this qualitative evaluation, 18 youth served by the network met in 4 focus groups to provide their view of the program. Services within 5 categories were assessed: (a) medical care, (b) mental health and substance abuse care, (c) HIV prevention and care, (d) case management, and (e) allocation of finances. Boston HAPPENS has achieved name recognition and provides many needed services for youth from a wide variety of backgrounds. The youth were comfortable receiving care and were appreciative of the comprehensive services available. They provided suggestions for how mental health services could be offered as one-on-one counseling as part of "wellness care." Young participants also requested more recreational and support opportunities for young people living with HIV.
Does youth perceptions of comprehensive adolescent health services through the Boston happen program?
10,736,140
{ "answer_start": [ -1 ], "text": [ "yes" ] }
A number of risk factors for chronic renal allograft rejection have been identified; in particular the number and severity of acute rejections, hypertension, hyperlipidemia, and insufficient immunosuppression. In a retrospective case control study, all histologically confirmed cases of chronic rejection (n=45) that occurred between 1985 and 1993 among patients transplanted at Huddinge Hospital were compared with twice as many controls. Determinants such as donor age and sex, HLA-mismatch, cold ischemia time, recipient age and sex, body mass index, cause of renal disease, time undergoing dialysis, condition of blood vessels at surgery, time of onset, number of acute rejection episodes during the first 3 months, area under the serum creatinine versus time curve (AUC(Creatinine)), blood pressure, blood lipids, and cyclosporine concentrations at various times after the transplantation were also compared. Additional data were obtained from a questionnaire, concerning 79% of the cases and controls. Cases and controls were similar with regard to most determinants, that is, blood pressure, blood lipids, and average cyclosporine concentrations. The main outstanding risk factor for chronic rejection was the time-averaged creatinine (AUC(Creatinine)) value between day 22 and 3 months after transplantation. The adjusted odds ratio for chronic rejection increased stepwise from 1.1 to 9.2, when AUC(Creatinine) increased from < 150 to >300 micromol/l. The number of acute rejection episodes and number of HLA-mismatches also had a significant effect on the risk of chronic rejection.
Is area under the serum creatinine time-curve a strong predictor of chronic renal allograft rejection?
10,755,558
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Increased expression of chemokine mRNA is observed in allogeneic but not syngeneic skin grafts 3-4 days after transplantation. The recipient cells mediating this early inflammatory response in allografts remain unidentified. Isogeneic and allogeneic skin grafts were transplanted to euthymic and athymic nude mice. mRNA expression and protein production of macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, and the murine homolog of Gro(alpha), i.e. KC, from graft homogenates retrieved 3-4 days posttransplantation was tested by Northern blot hybridization and ELISA. To deplete NK cells, recipients were treated with antiasialo GM1 (ASGM1) antisera or with anti-NK1.1 mAb before transplantation. Expression of KC, MIP-1alpha, and MIP-1beta mRNA was equivalent in C57BL/6 allogeneic skin grafts and BALB/c isografts at day 2 posttransplant. At day 3 posttransplant, chemokine mRNA levels decreased in isografts but were maintained at high levels in the allografts. Increased early chemokine mRNA was also observed in C57BL/6, but not BALB/c++ grafts on BALB/c athymi(nu/nu) recipients. Treatment of allograft recipients with ASGM1 or with anti-NK1.1 antibody eliminated NK cells from the spleen and allograft infiltrating cell populations and decreased early chemokine mRNA levels in allografts 60-70%. Analyses of allograft homogenates indicated increased levels of KC, MIP-1alpha, and MIP-1beta protein at day 4 posttransplant that were decreased in recipients depleted of NK cells. Early chemokine mRNA levels were equivalent in isogeneic and semiallogeneic F1 grafts.
Is early increased chemokine expression and production in murine allogeneic skin grafts mediated by natural killer cells?
10,755,559
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The boundary lubricating ability of human synovial fluid has been attributed to lubricin, a mucinous glycoprotein. We investigated the primary structure of lubricin and its cellular origin. Lubricin was purified from pooled synovial fluid aliquots with normal lubricating activity obtained from patients with osteoarthritis. Lubricating ability of lubricin was assayed in a friction apparatus that oscillates natural latex against a ring of polished glass. Native and lubricin deglycosylated with O-glycosidase DS and NANase III were trypsinized and sequenced by liquid chromatography mass spectrometry. Sequence results were compared to known structures in GenBank. Sequence data from strong matches were used in creating cDNA primers for reverse transcription-polymerase chain reaction (RT-PCR) with RNA from human synovial fibroblasts obtained intraoperatively. Purified lubricin possesses an apparent molecular weight of 280 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Deglycosylation decreased the apparent molecular weight on SDS-PAGE to 120 kDa. Sequences specific for megakaryocyte stimulating factor precursor (MSF) were identified in GenBank. A 100% match was observed for exons 6 though 9 of MSF. Lubricin/MSF reduced the coefficient of friction (m) in the latex:glass bearing from 0.131 to 0.047. MSF is 1404 amino acids in size with multiple functional domains similar to vitronectin. The reported structure of MSF contains a centrally located mucin (exon 6) with 76 repeats of the degenerate motif of KEPAPTT, the presumed site of extensive O-linked glycosylation. RT-PCR with primers complementary for Pro214- Ala307 in exon 6 and RNA from human synovial fibroblasts produced the predicted product size of 280 bp.
Is lubricin a product of megakaryocyte stimulating factor gene expression by human synovial fibroblasts?
10,743,795
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To determine the clinical significance of IgG antibodies to type II collagen (CII) and to define any correlation of antibodies to CII with the inflammatory response in patients with rheumatoid arthritis (RA). IgG antibodies to native human type II collagen (IgG anti-CII) were measured in sera and synovial fluid (SF) from patients with RA, patients with osteoarthritis (OA), and healthy controls by an improved ELISA. Demographic, clinical, and laboratory data including tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6) levels were also obtained at the time of sampling in patients with RA. The median level and positivity for circulating IgG anti-CII were higher in patients with RA (n = 297) than patients with OA (n = 34) and healthy controls (n = 50) (p < 0.001). The titers of IgG anti-CII in SF were also higher in RA (n = 45) than in OA (n = 16) (p < 0.001). In paired samples, the levels of IgG anti-CII were significantly higher in SF compared to the sera in patients with RA (n = 45) (p < 0.001), but levels were not different in patients with OA (n = 16). Circulating IgG anti-CII converted from positive to negative in 13 patients (10.7%) and from negative to positive in 18 patients (14.8%) among 122 patients with RA in whom IgG anti-CII were monitored sequentially at a mean interval of 12.2 months. IgG anti-CII positive patients (n = 98) had shorter disease duration (p = 0.04) and less frequent deformity (p = 0.013), and higher median erythrocyte sedimentation rate (ESR) (p = 0.001) and C-reactive protein (CRP) (p < 0.001) than IgG anti-CII negative patients (n = 120). The levels of IgG anti-CII correlated with CRP (r = 0.270) and ESR (r = 0.253). CRP decreased significantly in patients (n = 13) who converted from IgG anti-CII positive to negative (p = 0.013). IgG anti-CII positive patients (n = 40) had higher levels of TNF-alpha and IL-6 than negative patients (n = 40) (p < 0.001). Levels of IgG anti-CII correlated well with TNF-alpha (r = 0.617) and IL-6 (r = 0.347).
Do igG antibodies to type II collagen reflect inflammatory activity in patients with rheumatoid arthritis?
10,743,792
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Atherosclerosis is a multigenic process leading to the progressive occlusion of arteries of mid to large caliber. A key step of the atherogenic process is the proliferation and migration of vascular smooth muscle cells into the intimal layer of the arterial conduit. The phenotype of smooth muscle cells, once within the intima, is known to switch from contractile to de-differentiated, yet the regulation of this switch at the genomic level is unknown. Estrogen has been shown to regulate cell proliferation both for cancer cells and for vascular cells. However, methylation of the estrogen receptor-alpha gene (ERalpha) promoter blocks the expression of ERalpha, and thereby can antagonize the regulatory effect of estrogen on cell proliferation. We sought to determine whether methylation of the ERalpha is differentially and selectively regulated in contractile versus de-differentiated arterial smooth muscle cells. We used Southern blot assay, combined bisulfite restriction analysis (Cobra) and restriction landmark genome scanning (RLGS-M) to determine the methylation status of ERalpha in human aortic smooth muscle cells, either in situ (normal aortic tissue, contractile phenotype), or the same cells explanted from the aorta and cultured in vitro (de-differentiated phenotype). We provide evidence that methylation of the ERalpha in smooth muscle cells that display a proliferative phenotype is altered relative to the same cells studied within the media of non-atherosclerotic aortas. Thus, the ERalpha promoter does not appear to be methylated in situ (normal aorta), but becomes methylated in proliferating aortic smooth muscle cells. Using a screening technique, RLGS-M, we show that alteration in methylation associated with the smooth muscle cell phenotypic switch does not seem to require heightened activity of the methyltransferase enzyme, and appears to be selective for the ERalpha and a limited pool of genes whose CpG island becomes either demethylated or de novo methylated.
Is methylation of the estrogen receptor-alpha gene promoter selectively increased in proliferating human aortic smooth muscle cells?
10,727,665
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Sphingosine 1-phosphate is a naturally occurring biologically active lysophospholipid. Recent studies suggested that sphingosine 1-phosphate is released into the blood flow from activated platelets upon stimulation to exert multiple biological phenomenon. The purpose of this study was to assess the effects of sphingosine 1-phosphate on sinus automaticity, ventricular contraction and coronary blood flow. The canine isolated, blood-perfused sinoatrial node and papillary muscle preparations were used. Sphingosine 1-phosphate increased the sinoatrial rate, while it decreased the coronary blood flow, which was followed by a weak negative inotropic effect. These positive chronotropic and coronary vasoconstrictor effects were not attenuated by the beta- and alpha-adrenoceptor antagonists atenolol and prazosin, respectively. Furthermore, sphingosine 1-phosphate did not affect the adenylate cyclase activity of the membrane preparations made from the canine right atrium and right ventricle, indicating the involvement of a novel signaling pathway in sphingosine 1-phosphate-induced cardiac effects.
Does sphingosine 1-phosphate induce sinus tachycardia and coronary vasoconstriction in the canine heart?
10,727,660
{ "answer_start": [ -1 ], "text": [ "yes" ] }
This study was performed to assess whether there is any change in the T cell cytokine pattern in early rheumatoid arthritis (RA) patients treated with methotrexate (MTX) and whether the lymphocytic cytokine pattern correlates with disease activity. Eight patients with RA (disease duration < six months) were studied serially before, after three, and after six to nine months of treatment with MTX for the cytokines tumour necrosis factor alpha (TNFalpha), interferon gamma (IFNgamma), interleukin 4 (IL4) and interleukin 10 (IL10) by intracellular staining of T cells derived from peripheral blood. Response to treatment was assessed by the modified disease activitiy score. The clincial response was accompanied by a significant decrease of TNFalpha positive CD4(+) T cells from a median of 8.53% (interquartile range 5.83-10.91%) before treatment to 6.17% (2.15-6.81%) after six to nine months of treatment (p=0.021). Inversely, IL10 positive T cells increased from a median of 0.65% (interquartile range 0.6-0.93%) to a median of 1. 3% (1.22%-1.58%) after six to nine months of treatment (p=0.009). No significant change in the percentage of INFgamma positive T cells and a small decrease of IL4 positive T cells during treatment were observed. The percentage of IL4 positive CD4(+) T cells before treatment correlated with disease activity after six to nine months (r= -0.7066; p=0.05).
Is response to methotrexate in early rheumatoid arthritis associated with a decrease of T cell derived tumour necrosis factor alpha , increase of interleukin 10 , and predicted by the initial concentration of interleukin 4?
10,733,482
{ "answer_start": [ -1 ], "text": [ "yes" ] }
No previous studies have investigated the psychiatric characteristics of patients with postherpetic neuralgia (PHN). Similarly, no studies have been performed on patients with different chronic somatic symptoms due to a defined medical disease to compare the characteristics of psychiatric morbidity associated with each etiology. After completing the subscales of the Symptom Checklist 90-R, a psychiatrist administered the Diagnostic Interview Schedule to all subjects. The psychiatric comorbidity in 35 patients with pain due to PHN was compared with a control group of 34 patients with the nonpainful aversive symptom of vertigo due to a peripheral vestibular disorder that caused unilateral hypofunction. PHN patients had significantly more symptoms of major depression and somatization disorder. No significant differences were found between groups for psychiatric diagnoses. Patients with PHN reported significantly less acutely distressing somatic symptoms.
Do psychiatric symptoms and distress differ between patients with postherpetic neuralgia and peripheral vestibular disease?
10,750,630
{ "answer_start": [ -1 ], "text": [ "yes" ] }
This study examines how alexithymia and depression are related to each other in men and women in a sample of Finnish general population (n = 2018). Alexithymia was screened using the 20-item version of the Toronto Alexithymia Scale. Level of depression was assessed using the 21-item Beck Depression Inventory (BDI). Life satisfaction was estimated with a structured scale. The prevalence of alexithymia was 12.8% in men and 8.2% in women. However, the prevalence of alexithymia was 32.1% among those having BDI scores of > or = 9, but only 4.3% among the nondepressed subjects (p < 0.001). The BDI scores explained 29.2% of the variation in TAS-20 scores. Alexithymia was associated with several sociodemographic factors if depression was not taken into account. However, after including depression in the logistic regression models, only depression and low life satisfaction were associated with alexithymia, both in men and women.
Is depression strongly associated with alexithymia in the general population?
10,750,635
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To determine whether endothelin (ET)-dependent effects limit shear stress-induced dilation of large epicardial coronary arteries after blockade of nitric oxide (NO) formation. In conscious dogs instrumented for measuring coronary blood flow (CBF) and external diameter (CD) of the circumflex coronary artery, flow-dependent CD dilation was elicited by intracoronary (i.c.) adenosine (500 ng kg-1 min-1). I.c. adenosine increased CBF by 28 +/- 4 from 38 +/- 5 ml min-1 and CD by 0.25 +/- 0.03 from 3.53 +/- 0.07 mm without other hemodynamic effects. After N omega-nitro-L-arginine methyl ester (L-NAME), baseline CD fell (P < 0.01) to 3.35 +/- 0.08 mm but CBF was not significantly altered (36 +/- 5 ml min-1). CBF increases caused by adenosine were smaller (17 +/- 2 ml min-1, P < 0.05) and CD responses were nearly abolished (0.02 +/- 0.01 mm, P < 0.01). I.c. Ro 61-1790, an ETA receptor blocker, given after L-NAME did not significantly influence baseline CBF (36 +/- 5 ml min-1) but increased (P < 0.01) CD to 3.45 +/- 0.09 mm. CBF responses to adenosine were not significantly altered by Ro 61-1790 but CD responses (0.10 +/- 0.01 mm) were partially restored (P < 0.01). In contrast, blockade of ETB receptors with Ro 46-8443 after L-NAME had no further effects on CD and CBF responses to adenosine.
Do endothelin-dependent effects limit flow-induced dilation of conductance coronary vessels after blockade of nitric oxide formation in conscious dogs?
10,728,368
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Ovarian cancer is a well-known disease with a poor prognosis. Due to the relatively small number of cases in Taiwan, the outcome and prognostic factors of patients with primary epithelial ovarian carcinoma are unknown. We retrospectively studied patients with proven surgical and pathologic (Federation Internationale de Gynecologie et d'Obstetrique) FIGO IIIC primary epithelial ovarian carcinoma. All patients underwent standard staging surgery, including washing cytology, total abdominal hysterectomy, bilateral salpingo-oophorectomy, retroperitoneal lymphadenectomy, infracolic omentectomy and excisional biopsy of all suspicious lesions followed by adjuvant chemotherapy with four to 12 courses of cyclophosphamide, epirubicin and cisplatin (CEP) or cyclophosphamide, adriamycin and cisplatin (CAP) intravenously, every three weeks. To avoid the coeffects of chemotherapy and surgical procedures upon the outcome, patients who received paclitaxel-based regimens or underwent incomplete surgery were excluded. Ninety-eight patients from 1990 to 1996 were identified. The mean follow-up time was 28.7 months, ranging from 5.4 months to 105.9 months. The cumulative five-year disease-free survival rate for all patients was 31.6%. Optimal debulking surgery was completed in 41.8% of patients, which contributed to long-term patient survival (54% vs 16%, p < 0.0001), compared to patients without optimal debulking surgery. Optimal debulking surgery was the only statistically significant independent prognostic factor for five-year disease-free survival using multivariate analysis.
Is optimal debulking surgery an independent prognostic factor in patients with FIGO IIIC primary epithelial ovarian carcinoma?
10,746,418
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Hepatic resection is well established as a potentially curative treatment for hepatic colorectal cancer metastases. However, only a small proportion of patients with liver metastases are suitable for resection because they either have extrahepatic disease, or the extent and/or the distribution of their hepatic disease would make excision impossible. We have previously described the use of cryotherapy for inadequate resection margins and lesions in the remaining lobe of the liver. Combining such cryodestructive techniques with resection offers the possibility of increasing the proportion of patients to whom potentially curative treatment can be offered. The aim of this study was to compare survival in patients treated with resection and cryotherapy against those of patients treated with resection alone. Potential prognostic variables were also examined. Patients undergoing a hepatic resection with or without cryotherapy at our unit between April 1990 and July 1997 were identified from our database and their notes reviewed. Survival was estimated using the Kaplan-Meier method and compared using the Log rank test. One hundred and seven patients were treated in total: 32 underwent resection alone, and 75 underwent resection combined with cryotherapy. There was no significant difference between the survival of patients treated with resection alone and those treated with resection and cryotherapy.
Does resection with cryotherapy of colorectal hepatic metastases have the same survival as hepatic resection alone?
10,753,529
{ "answer_start": [ -1 ], "text": [ "yes" ] }
We have performed TNF-alpha gene transfection in a mouse mammary cancer line and found significant antitumor effects. We hypothesize that the antitumor effects observed in this model are mediated by ICAM-1 and by the recruitment of CD4+ and CD8+ T cells. In vivo (Balb/c mice) tumor growth inhibition, treatment of established tumor and the effects of ICAM-1 and CD4+ and CD8+ T cells were evaluated. Gene transfection with highly efficient vectors resulted in secretion of large amounts of TNF-alpha (ELISA). In vivo antitumor effects were tested. The number of cells required to generate palpable tumor 7-10 days after subcutaneous injection was determined (1 x 10(6)). The same number of transfected cells were injected subcutaneously and compared to nontransfected controls. Tumors were measured blindly and size was analyzed on day 30 by the Wilcoxon rank sum test. Mean tumor size after injection of transfected cells is compared to that of controls. Control tumors reached the maximum allowable size by day 30 (4 cm(2)). On day 30 EMT6-TNF-alpha tumors were 0.48 cm(2) (p < 0.05). The effect of repeat injection (challenge was also tested. Animals were injected with transfected cells or wild-type control on day -6 and challenged with the same number of wild-type tumor cells on day 0. Significant immune protection against subsequent challenge was seen after first time injection with EMT6-TNF-alpha but not after first time EMT6 wild-type injection (1.62 vs. 4 cm(2)). Treatment of 6-day-old tumor was also evaluated. On day 30, mean tumor size in animals treated with EMT6-TNF-alpha was 0.9 cm(2) compared to 4 cm(2) for controls. In all experiments, CD8+ T cell depletion and CD4+ T cell depletion caused a reversal of TNF-alpha-induced inhibitory effects. In addition, in vivo antibody blocking of ICAM-1 in tumor growth experiments reversed antitumor effects (control 4 cm(2), TNF-alpha 0.2 cm(2) and ICAM-1 blocking 3.14 cm(2)). Using flow cytometry, MHC class I and II and ICAM-1 adhesion molecule expression of transfected tumor was tested. ICAM-I expression was significantly upregulated. MHC class II antigen expression was also increased. TNF-alpha-transfected human breast cancer was also evaluated. Three cell lines and fresh tumor were transfected to express TNF-alpha. In vitro analysis revealed ICAM-1 upregulation following transfection. Histologic analysis and immunohistochemical staining revealed TNF-alpha and ICAM-1 in transfected tumors and not in wild-type tumors.
Is treatment of established tumor associated with ICAM-1 upregulation and reversed by CD8 depletion in a tumor necrosis factor-alpha gene transfected mouse mammary tumor?
10,738,180
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To investigate the potential of specific angiotensin II subtype 1 (AT1) receptor blockade to modify the mesenteric hemodynamic response to acute hypovolemia and retransfusion. Prospective, randomized, controlled experimental study. University-affiliated animal research laboratory. Fasted, anesthetized, ventilated, juvenile domestic pigs of both sexes. Acute, graded hypovolemia by 20% and 40% of the total estimated blood volume followed by retransfusion in control animals (CTRL; n = 10) and animals pretreated with the AT1 receptor blocker candesartan (CAND; n = 10). Invasive monitoring of arterial and central venous blood pressures, cardiac output, portal venous blood flow, and jejunal mucosal blood flow. Blood gases were repeatedly analyzed to calculate oxygen delivery and consumption. Thirty minutes after each level of hypovolemia at 20% and 40%, cardiac output was decreased in CTRL animals from a baseline of 2.9 +/- 0.1 to 1.8 +/- 0.2 and 1.1 +/- 0.2 L/min, with no differences compared with CAND animals. Cardiac output was restored to 3.0 +/- 0.3 L/min 30 mins after retransfusion in CTRL animals, with no significant intergroup differences. Baseline portal venous blood flow (Q(MES)) and jejunal mucosal perfusion (PU(JEJ)) were greater in CAND animals compared with CTRL animals. During graded hypovolemia, CAND animals maintained Q(MES) and PU(JEJ) at significantly higher levels compared with CTRL animals, particularly after 40% hemorrhage (+221% and + 244%, respectively, relative to the mean values in CTRL animals). The same pattern was observed after retransfusion. Moreover, the calculated mesenteric critical oxygen delivery was significantly greater in CTRL animals (74 mL/min) compared with CAND animals (34 mL/min). No animals died in the CAND group, whereas four animals died during 40% hypovolemia or retransfusion in the CTRL group.
Does specific angiotensin II receptor blockage improve intestinal perfusion during graded hypovolemia in pigs?
10,752,835
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To investigate the effect of multiple-dose paroxetine intake on the stereoselective pharmacokinetics and the pharmacodynamics of metoprolol. We conducted an open trial with two sessions in eight healthy male volunteers. Racemic metoprolol (100 mg single oral dose) was administered before and after paroxetine treatment (20 mg/day for 6 days). The (R)- and (S)-metoprolol pharmacokinetics, metoprolol metabolic ratio (MR), exercise heart rate and blood pressure were assessed for 12 (pharmacodynamic data) to 24 (pharmacokinetic data) hours after each metoprolol intake. Paroxetine treatment increased the mean area under the plasma concentration-time curve extrapolated to infinity (AUC) of (R)- and (S)-metoprolol significantly (169 to 1,340 ng x h/mL [P < .001] and 279 to 1,418 ng x h/mL [P < .001], respectively), with an approximately twofold increase in both maximum plasma concentration and terminal elimination half-life. Furthermore, the (S)/(R) AUC ratio was significantly decreased, from 1.72 to 1.07 (P < .001). The mean metoprolol MR was significantly increased, from 0.17 to 5.69 (P < .05). The AUC of the metoprolol-induced decrease in exercise heart rate versus time curve was increased, with 46% (P < .01) after multiple-dose paroxetine intake, reaching significance from 6 hours after metoprolol intake, illustrating a more sustained beta-blockade. Similar results were obtained for the effect on exercise systolic blood pressure. Multiple-dose metoprolol administration combined with paroxetine can lead to an accumulation of the beta-blocking (S)-enantiomer of metoprolol, possibly resulting in unacceptable bradycardia, loss of cardioselectivity, or both.
Does paroxetine affect metoprolol pharmacokinetics and pharmacodynamics in healthy volunteers?
10,741,632
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To evaluate if the preexistant filling state, assessed by right atrial pressure (RAP), pulmonary artery occlusion pressure (PAOP), and right ventricular end-diastolic volume index (EDVI), would define the subsequent hemodynamic effects of increases in airway pressure (Paw). Prospective open clinical study. Postoperative intensive care unit, university hospital. Twenty-two consecutive ventilator-dependent patients with mild to severe acute lung injury with Murray scores (scoring infiltrates on chest radiograph, oxygenation index, lung compliance, and the level of positive end-expiratory pressure) ranging from 0.5 to 3.0 without history of preexisting cardiopulmonary disease. Paw varied during apnea from 0 to 10, 20, and 30 cm H2O using inspiratory hold maneuvers of 15 secs. Cardiac index and right ventricular ejection fraction were measured by the thermodilution technique. We made measurements in triplicate using manual injection of iced saline. Right ventricular volumes were calculated. Increasing Paw induced variable changes in cardiac index among subjects (+6% to -43% change from baseline 0 cm H2O Paw values), which correlated with percentage changes in both stroke index (r2 = .89) and right ventricular EDVI (r2 = .75), whereas heart rate and right ventricular ejection fraction did not change. The change in cardiac index from 0 to 30 cm H2O Paw correlated with baseline values for RAP, PAOP, and right ventricular EDVI (r2 = .68, .43, and .34, respectively, p < 0.01). Increases in RAP correlated with lung compliance if baseline RAP was >10 mm Hg but did not if it was < or =10 mm Hg. Similarly, patients with baseline RAP < or =10 mm Hg had a greater decrease in cardiac index than patients with a RAP >10 mm Hg (for 30 cm H2O Paw: -30% +/- 9% vs. -8% +/- 7%, p < .01).
Does right atrial pressure predict hemodynamic response to apneic positive airway pressure?
10,752,813
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To investigate the additional effect of incentive spirometry to chest physiotherapy to prevent postoperative pulmonary complications after thoracic surgery for lung and esophageal resections. Randomized controlled trial. University hospital, intensive care unit, and surgical department. Sixty-seven patients (age, 59 +/- 13 yrs; forced expiratory volume in 1 sec, 93% +/- 22% predicted) undergoing elective thoracic surgery for lung (n = 40) or esophagus (n = 27) resection. Physiotherapy (breathing exercises, huffing, and coughing) (PT) plus incentive spirometry (IS) was compared with PT alone. Lung function, body temperature, chest radiograph, white blood cell count, and number of hospital and intensive care unit days were all measured. Pulmonary function was significantly reduced after surgery (55% of the initial value) and improved significantly in the postoperative period in both groups. However, no differences were observed in the recovery of pulmonary function between the groups. The overall score of the chest radiograph, based on the presence of atelectasis, was similar in both treatment groups. Eight patients (12%) (three patients with lobectomy and five with esophagus resection) developed a pulmonary complication (abnormal chest radiograph, elevated body temperature and white blood cell count), four in each treatment group. Adding IS to regular PT did not reduce hospital or intensive care unit stay.
Does incentive spirometry enhance recovery after thoracic surgery?
10,752,814
{ "answer_start": [ 911 ], "text": [ "no" ] }
Primary effusion lymphoma (PEL) associates with HHV-8 infection, preferentially develops in immunodeficient patients and grows in the serous body cavities. PEL derives from post-germinal center, pre-terminally differentiated B-cells. The pathogenesis of PEL is unclear and the sole identified genetic lesions are human herpesvirus type-8 (HHV-8) infection in all cases and EBV infection in 70% of cases. Epstein-Barr virus (EBV) infection in PEL displays a latency I phenotype. To clarify the pathogenesis and histogenesis of PEL by investigating (1) the lymphoma karyotype; (2) the expression status of the Met tyrosine kinase receptor and of its ligand hepatocyte growth factor (HGF); (3) the molecular profile of EBV, with particular focus on mutations of EBNA-1 genes, which are thought to affect viral tumorigenicity in EBV-infected neoplasms displaying the latency I phenotype. Twenty-four PEL (nine cell lines and 15 primary specimens) formed the basis of the study. Karyotypes were investigated by conventional cytogenetics and fluorescent in situ hybridization (FISH) in selected cases. The expression status of Met and HGF was defined by multiple techniques, including RT-PCR, FACS analysis, immunocytochemistry, Western blot studies and ELISA. The molecular profile of EBNA-1 genes of EBV were investigated by DNA direct sequencing. Trisomy 7, trisomy 12 and breaks at 1q21-q25 are recurrently associated with PEL. PEL consistently co-express Met and HGF both at the mRNA and protein level. Among aggressive B-cell lymphomas, Met/HGF co-expression appears to be relatively specific for PEL. The EBNA-1 gene of EBV displays a high degree of genetic heterogeneity in PEL, with no preferential association with one specific variant.
Does molecular characterization of HHV-8 positive primary effusion lymphoma reveal pathogenetic and histogenetic features of the disease?
10,738,140
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Methylenedioxymethamphetamine (MDMA) is known to damage brain pre-synaptic serotonin (5-HT) neurons. Since loss of 5-HT neurons has been implicated in memory loss, it is important to establish whether MDMA use may produce changes in postsynaptic 5-HT receptors and memory function in humans. To investigate whether MDMA use leads to compensative alterations in post-synaptic 5-HT2A receptors and whether there is a relation with memory disturbances. Brain cortical 5-HT2A receptor densities were studied with [123I]-5-I-R91150 SPECT in five abstinent MDMA users and nine healthy controls. Memory performance was assessed using RAVLT. [123I]-5-I-R91150 binding ratios were significantly higher in the occipital cortex of MDMA users than in controls, indicating up-regulation. Mean cortical 5-HT2A receptor binding correlated positively with RAVLT-recall in MDMA users.
Are memory disturbances in `` Ecstasy '' users correlated with an altered brain serotonin neurotransmission?
10,755,746
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Amphetamine (AMPH)-like stimulants represent an intensively studied class of psychoactive drugs. Despite the well-known and potent arousal-enhancing effects of these drugs, the neurobiological substrates of AMPH-induced arousal have rarely been examined explicitly. Activity of the locus coeruleus-noradrenergic system is causally and positively related to behavioral and electroencephalographic (EEG) indices of arousal. For example, activation of locus coeruleus neurons or stimulation of medial basal forebrain noradrenergic beta-receptors elicits activation of forebrain EEG in the anesthetized rat. Further, stimulation of noradrenergic beta-receptors within the medial basal forebrain elicits a substantial increase in alert, active waking. These and other observations suggest that at least some of the arousal-enhancing actions of AMPH-like stimulants derive from AMPH-induced increases in noradrenergic neurotransmission at beta-receptors. The current study examines the extent to which AMPH-induced activation of cortical EEG is dependent on actions of central beta-receptors. The effects of intracerebroventricular (ICV; 2 microl) pretreatment with either vehicle (artificial extracellular fluid) or the beta-antagonist, timolol (25, 50 or 100 microg), on the cortical EEG activating effects of intravenous AMPH (0.15 mg/kg) were examined in the halothane-anesthetized rat. EEG was recorded on polygraph and video recording tape and later analyzed using power spectral analyses (PSA). AMPH-induced alteration in cortical EEG activity was measured using PSA in vehicle- and timolol-pretreated animals. Neither vehicle nor timolol ICV infusions altered cortical EEG activity patterns. In vehicle-pretreated animals, AMPH elicited a robust activation of cortical EEG, characterized by the substantial decrease in large-amplitude, slow-wave activity. Timolol pretreatment dose-dependently prevented AMPH-induced cortical EEG activation. This effect of timolol was statistically significant at the 50 microg and 100 microg dose.
Is amphetamine-induced activation of forebrain EEG prevented by noradrenergic beta-receptor blockade in the halothane-anesthetized rat?
10,755,744
{ "answer_start": [ -1 ], "text": [ "yes" ] }
There is evidence from animal studies that lactose has a beneficial effect on intestinal calcium absorption. However, data concerning the effect of lactose on calcium absorption in lactose-tolerant adults are inconclusive. Our objective was to investigate the effect of lactose on calcium bioavailability in humans by the use of a stable-strontium test under controlled metabolic conditions. Eleven healthy, lactose-tolerant subjects (8 women, 3 men) randomly received a bolus of 2.27 mmol strontium alone (load A), the bolus with 35 g lactose (load B), or the bolus with 17.5 g glucose and 17.5 g galactose (load C). Blood samples were drawn at 0, 15, 30, 60, 90, 180, 240, and 300 min. Urine specimens were collected during the time intervals -2 to 0, 0-2, 2-4, 4-6, and 6-24 h. Pharmacokinetic parameters of strontium bioavailability were comparable for all 3 loads. In detail, fractional absorption at 240 min for loads A, B, and C was 12.1 +/- 0.7%, 13.0 +/- 1.1%, and 12.2 +/- 0.7%, respectively. Areas under the curve for 0-240 min were 70.8 +/- 6.3, 69.6 +/- 3.5, and 65.8 +/- 5.1 micromol*h/L for loads A, B, and C, respectively (NS). Moreover, fractional strontium excretion values of 5.1 +/- 0.8% (load A), 5.8 +/- 0.4% (load B), and 5.2 +/- 0.8% (load C) were not significantly different.
Does lactose enhance calcium bioavailability in lactose-tolerant , healthy adults?
10,731,499
{ "answer_start": [ 1272 ], "text": [ "no" ] }
n-3 Fatty acids lower plasma triacylglycerols not only in the fasting state but also in the postprandial state. However, it is not known whether chylomicrons, chylomicron remnants, and VLDLs are all affected equally or whether some lipoprotein species are lowered preferentially. Lipoproteins, including large and small chylomicron remnants, were determined specifically with the aid of a newly developed method involving a combination of size-exclusion chromatography and fluorometric determination of retinyl palmitate, which served as a marker for exogenous fat. Twelve hypertriacylglycerolemic men were treated for 6 wk with 4 capsules containing 85% fish-oil concentrate/d; each capsule contained 850 mg n-3 fatty acid ethyl esters (49.1% eicosapentaenoic acid by wt and 32.2% docosahexaenoic acid by wt). Oral-fat-tolerance tests were performed before and after the treatment. Blood samples were drawn in the fasting state and until 8 h postprandially. Treatment with n-3 fatty acids reduced the fasting VLDL-triacylglycerol concentration by 44% (P < 0.05) and postprandial chylomicrons and VLDLs at 4, 6, and 8 h (P < 0.05) by 49-64% and 36-43%, respectively. Chylomicron remnants were reduced only in the late postprandial phase: large chylomicron remnants by 19% at 6 h and by 43% at 8 h (P < 0.05) and small chylomicron remnants by 31% at 8 h (P < 0.05).
Are postprandial chylomicrons and VLDLs in severe hypertriacylglycerolemia lowered more effectively than are chylomicron remnants after treatment with n-3 fatty acids?
10,731,497
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Adipose tissue (AT) content of the thigh is generally not considered to be associated with insulin resistance (IR), but it is unclear whether the distribution of AT in the thigh is a determinant of IR. We investigated whether subcompartments of AT within the thigh are determinants of IR. Midthigh AT, muscle composition, and insulin sensitivity were compared in 11 obese patients with type 2 diabetes mellitus (DM); 40 obese, glucose-tolerant (GT) and 15 lean, GT volunteers; and 38 obese subjects who completed a weight-loss program. Midthigh AT area measured with computed tomography was partitioned into 3 components: subcutaneous AT (SCAT), AT beneath the fascia (SFAT), and AT infiltrating muscle groups (IMAT). Muscle attenuation characteristics were determined. Obese DM and obese GT subjects had lower insulin sensitivity than lean GT subjects. SCAT was greater in obesity, yet did not correlate with insulin sensitivity. SFAT was approximately 8% of total thigh AT and correlated with insulin sensitivity. IMAT was highest in obese DM, and although it accounted for only approximately 3% of thigh AT, it was a strong correlate of insulin sensitivity. Mean attenuation was highest in lean subjects and was associated with higher insulin sensitivity. Weight loss reduced the amount of thigh AT, the proportion of thigh IMAT, and the amount of low-density thigh muscle.
Is thigh adipose tissue distribution associated with insulin resistance in obesity and in type 2 diabetes mellitus?
10,731,493
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The influence of age on early and late outcome after surgical resection of bronchogenic carcinoma is unknown. In an attempt to clarify this issue, we reviewed the outcome of 212 consecutive patients with primary lung cancer who had surgical treatment for bronchogenic carcinoma. Ninety-two patients were younger than 50 years (group 1), and 120 patients were older than 70 years of age (group 2). Squamous cell carcinoma and adenocarcinoma were the most common histologic types in both groups. According to the new international staging classification, a similar proportion of stage I, II, and III were observed in both groups. Only the rate of pneumonectomy was significantly higher in younger patients (41% versus 22%, p = 0.002). The overall operative mortality rate in group 1 was 2.2% and 2.6% after pneumonectomy. In group 2 the overall mortality rate was 2.5% and 3.8% after pneumonectomy. Advanced age did not affect operative mortality. The adjusted (tumor-related) survival rate at 5 years was 56% in group 1 and 53% in group 2 (p = 0.93). The adjusted survival rate for patients with stage I was 61% in group 1 and 65% in group 2 (p = 0.21), and for stage IIIa 39% in group 1 and 48% in group 2 (p = 0.43). The adjusted 5-year survival rate was 56% in group 1 and 59% in group 2 for squamous cell carcinoma (p = 0.53) and 49% in group 1 and 42% in group 2 for adenocarcinoma (p = 0.76).
Does age influence early and late tumor-related outcome for bronchogenic carcinoma?
10,750,783
{ "answer_start": [ 93 ], "text": [ "no" ] }
The heat shock protein (hsp27) correlates with thermotolerance and chemoresistance. Our main objective was to assess the response to radiotherapy both in vitro and in vivo in correlation with various concentrations of hsp27. The second objective was to evaluate the relation between hsp27 and glutathione-s-transferase pi (GST pi). For the in vitro study, thermoresistant cell lines, expressing various amounts of hsp27, were used to assess the role of this protein in radioresistance. To verify the efficiency of hsp27 in these cells lines to confer resistance to cytotoxic agents, these cells were also treated with heat shock and cisplatin. Furthermore, the role of hsp27 expression was studied in vivo by immunochemistry in 98 patients with head and neck squamous cell carcinoma treated by radiotherapy. hsp27 was correlated with local control of the tumor and with clinical and biologic factors potentially able to affect the local control, including p53, ki-67, ploidy, and GST. In vitro, high constitutive levels of expression of hsp27 did not significantly influence the survival curves of transfected cells exposed to radiation as compared to control cells although hsp27 overexpression was confirmed to increased the cellular resistance to heat and to cisplatinum. In vivo, we showed that overexpression of various amounts of hsp27 did not correlate with local control of the tumor. In vivo, hsp27 was only significantly associated with GST pi. Expression of GST pi was associated with poor local (p = 0.01) control and survival (p = 0.08) in a Cox model.
Is overexpression of the 27 KDa heat shock protein associated with thermoresistance and chemoresistance but not with radioresistance?
10,725,639
{ "answer_start": [ -1 ], "text": [ "yes" ] }
We tested the hypothesis that propofol, acting in the brain, would either enhance, or have no effect, on lumbar dorsal horn neuronal responses to a noxious mechanical stimulus applied to the hindlimb. We recorded the response of lumbar dorsal horn neurons during differential delivery of propofol to the brain and torso of goats. Goats were anesthetized with isoflurane and neck dissections performed which permitted cranial bypass. A laminectomy was made to allow microelectrode recording of lumbar dorsal horn neuronal activity. Isoflurane was maintained at 0.8+/-0.1% to both head and torso throughout the study. During cranial bypass propofol was separately administered to the torso (1 mg x kg(-1), n = 7; 3.75 mg x kg(-1), n = 8) or cranial (0.04 mg x kg(-1), n = 7; 0.14 mg kg(-1), n = 8) circulations. Propofol administered to the torso depressed dorsal horn neuronal responses to noxious stimulation: low dose: 500+/-243 to 174+/-240 impulses x min(-1) at one minute post-injection, P<0.001; high dose: 478+/-204 to 91+/-138 impulses x min(-1) at one minute post-injection, P<0.05). Propofol administered to the cranial circulation had no effect: low dose: 315+/-150 to 410+/-272 impulses x min(-1), P>0.05; high dose: 462+/-261 to 371+/-196 impulses x min(-1), P>0.05.
Does propofol directly depress lumbar dorsal horn neuronal responses to noxious stimulation in goats?
10,730,741
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Retinal pigment epithelial (RPE) cells are believed to play a pivotal role in the formation and contraction of epiretinal membranes in proliferative vitreoretinopathy (PVR). In the present study, an organ culture method was used that mimics the contractile stage of PVR, to investigate the contribution of a variety of growth factors in human RPE cell-mediated contraction of the retina. Cultured human RPE cells were seeded onto bovine retinal explants. After attachment, cultures received one of the following exogenous growth factors: platelet-derived growth factor (PDGF)-AB, PDGF-BB, basic fibroblast growth factor (bFGF), transforming growth factor (TGF)-beta1, TGF-beta2, or interleukin (IL)-10; or a neutralizing antibody to PDGF and/or TGF-beta2. Control explants were either untreated or received a null antibody. Contraction was assessed by image analysis and expressed as percentage reduction in retinal area. RPE cells produced a more than 50% contraction of the retina after 7 days in untreated samples. PDGF and TGF-beta2 stimulated RPE-mediated contraction by a further 20% at 100 ng/ml. IL-10 decreased contraction by 63%, whereas the other growth factors gave rise to similar contraction to untreated controls. Neutralizing antibodies against PDGF and TGF-beta2 reduced RPE-mediated contraction by up to 70% in comparison with untreated controls. The neutralizing antibodies also inhibited the effects of exogenous PDGF and TGF-beta2 on RPE-mediated contraction of the retina (P < 0.01).
Do iL-10 and antibodies to TGF-beta2 and PDGF inhibit RPE-mediated retinal contraction?
10,752,962
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Oesophageal cancer is generally associated with late presentation and poor prognosis. Therefore palliative surgery has been largely superseded by less invasive non-surgical techniques. Once palliation is indicated, the aims of the management should be: the maintenance of oral intake, minimizing hospital stay, relief of pain, elimination of reflux and regurgitation and the prevention of aspiration. This study was a review of all published English language data on the palliation of malignant dysphagia between 1994-1999. The Medline and Bids databases were searched and other references were derived from the material perused.
Do an update in the palliative management of malignant dysphagia?
10,744,928
{ "answer_start": [ -1 ], "text": [ "yes" ] }
We used a murine model of orthotopic corneal transplantation to determine whether host deficiency in ICAM-1 promotes survival of corneal grafts with different degrees of allodisparity. ICAM-1-/- and wild-type C57BL/6 (ICAM-1+/+) received corneal grafts from the following strains of mice: BALB/c (fully mismatched), BALB.b (mismatched at multiple minor H only), or B10.D2 [including major histocompatibility complex (MHC) mismatch]. Graft rejection, induction of allospecific delayed-type hypersensitivity (DTH) responses, and leukocytic infiltration of grafts were measured. There were no differences in long-term survival of allografts that were either fully mismatched or had only minor H disparity in ICAM-1+/+ vs. ICAM-1-/-hosts. However, whereas B10.D2 grafts were accepted in only 58% of the ICAM-1+/+ hosts, graft survival in ICAM-1-/- recipients was 100% (P=0.006). Moreover, none of the ICAM-1-/- mice receiving B10.D2 grafts developed allospecific DTH.
Does iCAM-1 deficiency suppress host allosensitization and rejection of MHC-disparate corneal transplants?
10,755,569
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Erythromycin has been found to be a gastrointestinal prokinetic agent of hypertonic liquids, while acute hyperglycemia has been associated with delayed gastric emptying in diabetic patients. To investigate whether hyperglycemia, per se, reduces gastric motility during erythromycin-induced acceleration on gastric emptying of hypertonic liquids in diabetic patients. In 12 type-I diabetic patients following a hypertonic radiolabeled liquid meal, gastric emptying was measured scintigraphically during normoglycemia (5-8.9 mmol/l glucose) or hyperglycemia induced by intravenous (16-19 mmol/l) glucose infusion. The tests were performed on 4 separate days in random order after administering either placebo or 200 mg i.v. erythromycin. In the hyperglycemic state compared to normoglycemia, the gastric emptying of the hypertonic liquid was reduced after placebo or erythromycin administration. The lag-phase duration (17.8+/-5.5 and 7.8+/-4.5 vs. 10.8+/-3.4 and 3.7+/-2.5 min, respectively, p<0.001), the overall gastric emptying time of the half meal (52.8+/-13 and 24.9+/-5.5 vs. 42.5+/-10.5 min and 16.6+/-6 min, respectively, p<0.001) and the retained percentage of liquid meal in the stomach at 60 and 100 min postprandially (p<0.001) were significantly increased.
Does induced-hyperglycemia attenuate erythromycin-induced acceleration of hypertonic liquid-phase gastric emptying in type-I diabetic patients?
10,754,365
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Age-related defects in the development of peripheral inflammatory responses have been observed in rodents and humans. We examined the effects of age on a centrally injected endotoxin-induced cytokine production and cellular activation in mice. Male C57BL/6J (B6) mice, C3H/HeN mice, and C3H/HeJ mice received an intracerebroventricular injection of lipopolysaccharide (LPS) and were sacrificed at various times (2, 4, 8 h) thereafter. ELISA for IL-1beta, IL-6, IL-12, and TNF-alpha were conducted on forebrain tissue homogenates as well as plasma samples, and lectin staining to detect activated microglia was prepared for selected brain slices. Intracerebroventricular injection of LPS in B6 mice produced an age-associated increase in mortality which was paralleled with a significant increase in brain and plasma levels of TNF-alpha. AntiTNF-alpha- and IL-6-immunoreactive cells possessed macrophagelike morphologies and were observed along the LPS injection tract and scattered throughout the hilus of the dorsal hippocampus and cerebral cortices. This LPS-mediated response was found to be specific in that the LPS-hyporesponsive mouse strain (C3H/HeJ) failed to demonstrate significant brain or plasma levels of TNF-alpha after LPS administration compared to C3H/HeN mice.
Do aged mice exhibit greater mortality concomitant to increased brain and plasma TNF-alpha levels following intracerebroventricular injection of lipopolysaccharide?
10,754,368
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Radiofrequency applications to the posteroseptal region can ablate the atrioventricular accessory pathway residing in this area. In conjunction with the adjacent anatomic structures, however, ablative lesions which do not effectively ablate the accessory pathway could markedly alter retrograde atrial activation sequence and confound interpretation of further mapping of an accessory pathway. Electrophysiologic studies, endocardial activation mapping and radiofrequency catheter ablation were undertaken in three patients with recurrent supraventricular tachycardia. Patients were initially thought to have a single posteroseptal accessory pathway; earliest ventrioatrial activation during tachycardias and during ventricular pacing was at the coronary sinus ostium, but initial radiofrequency applications were unsuccessful to ablate the pathway. After initial radiofrequency applications to the posteroseptal region, the earliest retrograde atrial activation changed to the right atrial free wall in two patients. Additional radiofrequency application to the posteroseptal area was able to ablate the single posteroseptal accessory pathway in one patient. Radiofrequency application to the right atrial free wall was required to stop tachycardia initiation in other patient. The third patient was suspected of having a slow-slow atrioventricular nodal reentry tachycardia. Radiofrequency application to the posteroseptal area changed the earliest retrograde atrial activation to the distal coronary sinus recording site, mimicking an accessory pathway at the left atrial free wall. Radiofrequency application to the anteroseptum was able to ablate the concealed accessory pathway.
Does radiofrequency application to the posteroseptal region alter retrograde accessory pathway activation?
10,729,849
{ "answer_start": [ -1 ], "text": [ "yes" ] }
This study investigated whether off-pump coronary bypass graft operations on the beating heart under normothermic conditions reduces the systemic oxidative stress and inflammatory reaction seen in patients operated under cardiopulmonary bypass (CPB). A cardiac stabilizer (Octopus Tissue Stabilizer; Medtronic Inc, Minneapolis, MN) was used to perform the coronary anastomoses on the normothermic beating heart with or without CPB. Serial blood samples were taken at various intervals. Plasma was analyzed for several oxidative stress and inflammatory markers. Significant increases from prior anesthesia values of lipid hydroperoxides (190% at 4 hours), protein carbonyls (250% at 0.5 hours) and nitrotyrosine (510% at 0.5 hours) were seen in the CPB group, but they were abolished or significantly reduced in the off-pump group. Complement C3a and elastase levels were rapidly increased upon the institution of CPB, and this was followed by increases in IL-8, TNF-alpha, and sE-selectin. In contrast, the rise of these factors was blunted in patients operated without CPB.
Does off-pump bypass graft operation significantly reduce oxidative stress and inflammation?
10,750,762
{ "answer_start": [ -1 ], "text": [ "yes" ] }
21-aminosteroids (lazaroids) have demonstrated the protective effect against cerebral ischemic injury through the inhibition of lipid peroxidation. We examined whether lazaroids affected the production of proinflammatory and antiinflammatory cytokines in ischemic spinal cord injury model. Anesthetized New Zealand white rabbits underwent a 20-minute infrarenal aortic cross-clamping (AXC) with pretreatment of either an intravenous 3 mg/kg lazaroid U74389G (group L; n = 10) or the same volume saline (group P; n = 10). Sham operation group (group S; n = 6) underwent only exposure of the aorta. Plasma concentrations of interleukin (IL)-8, -1beta, -1 receptor antagonist (IL-1ra) and tumor necrosis factor (TNF)-alpha were measured at four time points. Functional assessment with Tarlov score at 24 and 48 hours after pretreatment, pathologic assessment of the spinal cord, and measurements of cytokine levels in the spinal cord were performed. The maximum elevation of plasma IL-8 and -1ra levels occurred at 1 hour after declamping in four measurement points. Plasma IL-8 and -1ra levels in group L were significantly lower than those in group P (*p < 0.05). Plasma TNFalpha peaked at 5 minutes after declamping, but decreased afterwards. Plasma TNFalpha levels were not different among three groups. Spinal IL-8 levels in group L (0.98 +/- 0.34 ng/g tissue) were lower than those in group P (7.26 +/- 2.26 ng/g tissue)(*p < 0.05). Spinal IL-1ra and TNFalpha were not significantly different. Tarlov score and pathologic assessment were better in group L.
Does lazaroid reduce production of IL-8 and IL-1 receptor antagonist in ischemic spinal cord injury?
10,750,763
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Despite the widespread availability of dialytic and intensive care unit technology, the probability of early mortality in critically ill patients with acute renal failure is still high. Previous efforts to predict the outcome in this population have been limited by small sample sizes. In addition, data obtained decades ago may not apply today owing to changes in the case mix. We have attempted to determine whether organ system failures can be used to predict prognosis. The medical records of 100 consecutive intensive care unit patients with acute renal failure who required dialysis from January 1997 through December 1998 were evaluated by a blinded reviewer. Of the 100 patients studied, 65 were men and 35 were women. The mean age of survivors and non-survivors was 59.4 +/- 20.3 years and 58.3 +/- 20.0 years, respectively. The overall mortality rate was 71%. There were no significant differences between survivors and non-survivors in age, gender, or indication for dialysis. The cause of death in the majority of patients was related to organ system failure, and they carried mortality rates exceeding 83% with the coexistence of four or more failed organs.
Do organ system failures predict prognosis in critically ill patients with acute renal failure requiring dialysis?
10,746,404
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To assess the effect of newborn circumcision on the incidence and medical costs of urinary tract infection (UTI) during the first year of life for patients in a large health maintenance organization. Kaiser Permanente Medical Care Program of Northern California (KPNC). The population consisted of members of KPNC. The study group consisted of a cohort of 28 812 infants delivered during 1996 at KPNC hospitals; of the 14 893 male infants in the group, 9668 (64.9%) were circumcised. A second cohort of 20 587 infants born in 1997 and monitored for 12 months was analyzed to determine incidence rates. Retrospective study of all infants consecutively delivered at 12 facilities. Diagnosis of UTI was determined from the KPNC computerized database using the International Classification of Diseases, Ninth Revision code for inpatients and KPNC Outpatient Summary Clinical Record codes for outpatients. A sample of 52 patient charts was reviewed to confirm the International Classification of Diseases, Ninth Revision and KPNC Outpatient Summary Clinical Record codes and provide additional data. Infants <1 year old who were born in 1996 had 446 UTIs (292 in females; 154 in males); 132 (86%) of the UTIs in males occurred in uncircumcised boys. The mean total cost of managing UTI was 2 times as high in males ($1111) as in females ($542). This higher total cost reflected the higher rate of hospital admission in uncircumcised males with UTIs (27.3%) compared with females (7.5%); mean age at hospitalization for UTI was 2.5 months old for uncircumcised boys and 6.5 months old for girls. In 1996, total cost of managing UTI in uncircumcised males ($155 628) was 10 times higher than for circumcised males ($15 466) despite the fact that uncircumcised males made up only 35.1% of the male patient base in 1996, reflecting the more frequent occurrence of UTI in uncircumcised males (132 episodes) than in circumcised males (22 episodes), and the larger number of hospital admissions in uncircumcised males (38) than in circumcised males (4). The incidence of UTI in the first year of life was 1:47 (2.15%) in uncircumcised males, 1:455 (.22%) in circumcised males, and 1:49 (2. 05%) in females. The odds ratio of UTI in uncircumcised:circumcised males was 9.1:1.
Does newborn circumcision decrease incidence and costs of urinary tract infections during the first year of life?
10,742,321
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Magnetic fields have been shown to affect cell proliferation and growth factor expression in cultured cells. Although the activation of endorphin systems is a recurring motif among the biological events elicited by magnetic fields, compelling evidence indicating that magnetic fields may modulate opioid gene expression is still lacking. We therefore investigated whether extremely low frequency (ELF) pulsed magnetic fields (PMF) may affect opioid peptide gene expression and the signaling pathways controlling opioid peptide gene transcription in the adult ventricular myocyte, a cell type behaving both as a target and as a source for opioid peptides. Prodynorphin gene expression was investigated in adult rat myocytes exposed to PMF by the aid of RNase protection and nuclear run-off transcription assays. In PMF-exposed nuclei, nuclear protein kinase C (PKC) activity was followed by measuring the phosphorylation rate of the acrylodan-labeled MARCKS peptide. The effect of PMF on the subcellular distribution of different PKC isozymes was assessed by immunoblotting. A radioimmunoassay procedure coupled to reversed-phase high performance liquid chromatography was used to monitor the expression of dynorphin B. Here, we show that PMF enhanced myocardial opioid gene expression and that a direct exposure of isolated myocyte nuclei to PMF markedly enhanced prodynorphin gene transcription, as in the intact cell. The PMF action was mediated by nuclear PKC activation but occurred independently from changes in PKC isozyme expression and enzyme translocation. PMF also led to a marked increase in the synthesis and secretion of dynorphin B.
Do elf-pulsed magnetic fields modulate opioid peptide gene expression in myocardial cells?
10,728,432
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Three-year colonoscopic surveillance after initial polypectomy may not be required for all patients. Those with multiple baseline polyps and large adenomas, implicated as predictors of colon cancer, merit close observation. Conversely, patients with single small adenomas may be subjected to early endoscopic surveillance unnecessarily. From our Adenoma Registry we evaluated patient and adenoma characteristics in 697 patients. All had an adenoma recurrence within 3 years of a positive baseline colonoscopy. Potential risk factors studied were age, gender, number of adenomas, size of largest adenoma and histology. We defined a significant outcome as size of 1 cm or greater, tubulovillous or villous histology, high-grade dysplasia, carcinoma in situ, invasive cancer, or 4 or more adenomas. Having 3 or more adenomas on initial colonoscopy with at least 1 measuring 1 cm or larger greatly increased the chance of a significant finding on the first surveillance colonoscopy. Conversely, patients with 1 or 2 adenomas all measuring less than 1 cm were at extremely low risk of an important outcome within 3 years.
Are adenoma size and number predictive of adenoma recurrence : implications for surveillance colonoscopy?
10,744,815
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Although estrogen replacement therapy has been associated with reduction of cardiovascular events in postmenopausal women, the mechanism for this benefit remains unclear. Because nitric oxide (NO) is considered an important endothelium-derived relaxing factor and may function to protect blood vessels against atherosclerotic development, we investigated the acute effects of physiological levels of estrogen on NO release from human internal thoracic artery endothelia and human arterial endothelia in culture. We tested the hypothesis that estrogen acutely stimulates constitutive NO synthase activity in human endothelial cells by acting on a cell-surface receptor. NO release was measured in real time with an amperometric probe. 17beta-Estradiol exposure to internal thoracic artery endothelia and human arterial endothelia in culture stimulated NO release within seconds in a concentration-dependent manner. 17beta-Estradiol conjugated to bovine serum albumin also stimulated NO release, suggesting action through a cell-surface receptor. Tamoxifen, an estrogen receptor inhibitor, antagonized this action. We further showed with the use of dual emission microfluorometry that 17beta-estradiol-stimulated release of endothelial NO was dependent on the initial stimulation of intracellular calcium transients.
Do cell-surface estrogen receptors mediate calcium-dependent nitric oxide release in human endothelia?
10,747,354
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The aim of the present study was to investigate the effects of inulin on calcium metabolism. The study consisted of two separate parts both of which had a randomized two-period cross-over design. Fifteen young healthy women volunteered to participate in this study. During the first part of the study, cheese containing 210 mg of calcium, either with 15 g of inulin or without any inulin, was ingested at breakfast, and in the second part, 210 mg of calcium as a supplement, either with 15 g inulin or without inulin, was ingested. The whole day's diet was standardized. Before breakfast, and 2, 4, 6 and 8 h after breakfast, a blood sample was taken, and intact parathyroid hormone (iPTH), ionized calcium (iCa) and total calcium were measured. Urine was collected throughout the day, and the 8-, 12- and 24-hour calcium excretion was calculated. The iPTH or iCa concentration curves (AUCs) did not differ over 8 h, whether or not inulin was consumed at breakfast. The postload urinary calcium excretion was not affected by the inulin.
Does addition of inulin to breakfast acutely affect serum ionized calcium and parathyroid hormone concentrations?
10,725,769
{ "answer_start": [ 896 ], "text": [ "no" ] }
Incomplete mitral leaflet coaptation during acute left ventricular ischemia is associated with end-diastolic mitral annular dilatation and ischemic mitral regurgitation. Annular rings were implanted in sheep to investigate whether annular reduction alone is sufficient to prevent mitral regurgitation during acute posterolateral left ventricular ischemia. Radiopaque markers were inserted around the mitral anulus, on papillary muscle tips, and on the central meridian of both mitral leaflets in three groups of sheep: control (n = 5), Physio ring (n = 5) (Baxter Cardiovascular Div, Santa Ana, Calif), and Duran ring (n = 6) (Medtronic Heart Valve Div, Minneapolis, Minn). After 8 +/- 1 days, animals were studied with biplane videofluoroscopy before and during left ventricular ischemia. Annular area was calculated from 3-dimensional marker coordinates and coaptation defined as minimal distance between leaflet edge markers. Before ischemia, leaflet coaptation occurred just after end-diastole in all groups (control 17 +/- 41, Duran 33 +/- 30, Physio 33 +/- 24 ms, mean +/- SD, P >.2 by analysis of variance). During ischemia, regurgitation was detected in all control animals, and leaflet coaptation was delayed to 88 +/- 8 ms after end-diastole (P =.02 vs preischemia). This was associated with increased end-diastolic annular area (8.0 +/- 0.9 vs 6.7 +/- 0.6 cm(2), P =.004) and septal-lateral annular diameter (2.9 +/- 0.1 vs 2.5 +/- 0.1 cm, P =.02). Mitral regurgitation did not develop in Duran or Physio sheep, time to coaptation was unchanged (Duran 25 +/- 25 ms, Physio 30 +/- 48 ms [both P >.2 vs preischemia]), and annular area remained fixed.
Does ring annuloplasty prevent delayed leaflet coaptation and mitral regurgitation during acute left ventricular ischemia?
10,733,769
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The treatment of choice for aortic valve insufficiency due to root dilatation has become root replacement with aortic valve sparing. However, root replacement with a synthetic graft may result in altered valve stresses. The purpose of this study was to compare the stress/strain patterns in the spared aortic valve in different root replacement procedures by means of finite element modeling. Our finite element model of the normal human root and valve was modified to simulate and evaluate three surgical techniques: (1) "cylindrical" graft sutured below the valve at the anulus, (2) "tailored" graft sutured just above the valve, and (3) "pseudosinus" graft, tailored and sutured below the valve at the anulus. Simulated diastolic pressures were applied, and stresses and strains were calculated for the valve, root, and graft. Leaflet coaptation was also quantified. All three root replacement models demonstrated significantly altered leaflet stress patterns as compared with normal patterns. The cylindrical model showed the greatest increases in stress (16%-173%) and strain (10%-98%), followed by the tailored model (stress +10%-157%, strain +9%-36%). The pseudosinus model showed the smallest increase in stress (9%-28%) and strain (2%-31%), and leaflet coaptation was closest to normal.
Is re-creation of sinuses important for sparing the aortic valve : a finite element study?
10,733,765
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Recently, we developed a new method to measure collateral blood flow in rats: splenorenal shunt (SRS) blood flow (BF). The aims were to evaluate the reproducibility of SRSBF measurement in different models of portal hypertension, and to investigate the ability of SRSBF to disclose pharmacological changes. Hemodynamics were determined in anesthetized rats with secondary biliary, CCl4 or DMNA cirrhosis and portal vein ligation (PVL) under baseline and pharmacological (octreotide, vapreotide) conditions. The main measurements performed were: SRSBF by the transit time ultrasound (TTU) method and % portosystemic shunts (PSS) by the microsphere method. SRSBF was 6 to 10 times higher in portal hypertensive rats and was similar in the different models of cirrhosis but was higher in portal vein ligated rats than in cirrhotic rats (1.1+/-0.7 vs 0.6+/-0.7 ml x min(-1) x 100 g(-1), p=0.01). SRSBF was correlated with mesenteric %PSS (r=0.61, p<0.01), splenic %PSS (r=0.54, p<0.05), portal pressure (r= 0.32, p<0.05) and the area of liver fibrosis (r=0.33, p<0.05). Octreotide significantly decreased SRSBF (-23+/-20%, p<0.01 vs placebo: -6+/-8%, NS). Vapreotide significantly decreased SRSBF but not mesenteric or splenic %PSS compared to placebo. The variations in SRSBF (-26+/-32%) and in splenic %PSS (0+/-15%) with vapreotide were significantly different (p<0.05) and not correlated (r=-0.1, NS).
Is spleno-renal shunt blood flow an accurate index of collateral circulation in different models of portal hypertension and after pharmacological changes in rats?
10,735,613
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Severe alcoholic hepatitis occurs mainly in patients with cirrhosis, and has a high death rate. Corticosteroid therapy has been particularly advocated as reducing mortality in patients with severe histologic lesions. However, identification of these patients is difficult, requiring transvenous liver biopsy. Extracellular matrix serum markers have been proposed as non-invasive diagnostic tools in alcoholic liver disease. The aim of this study was to determine the accuracy of 5 extracellular matrix serum markers, i.e. laminin (Lam), N-terminal peptide of type III procollagen (PIIINP), type I (CI), type III (CIII) and type IV (CIV) collagens in identifying patients with severe histologic alcoholic hepatitis from among those with cirrhosis and suspected alcoholic hepatitis. We studied 80 consecutive patients with alcoholic cirrhosis and clinical suspicion of alcoholic hepatitis referred for transvenous liver biopsy. Clinical severity of alcoholic hepatitis was assessed according to Maddrey's score. Histological severity was scored using the sum of the 3 following items: polynuclear infiltration (0-3); hepatocytes alterations (0-3); Mallory bodies (0-2). According to this score, patients were divided into 3 groups: mild (1-3), moderate (4-6), and severe (7-8) alcoholic hepatitis. Serum levels of the 5 extracellular matrix serum markers were measured at the time of biopsy using radioimmunoassays. Diagnostic value for histologically severe alcoholic hepatitis of the 5 extracellular matrix serum markers was assessed using receiver operating characteristic curves. Histological alcoholic hepatitis was present in 67 patients (mean alcoholic hepatitis score: 3.4+/-2.3). Maddrey's score was 66% sensitive and 69% specific for the diagnosis of severe histologic alcoholic hepatitis. The serum Lam and CIV concentrations were the most accurate in identifying correctly patients with severe histologic alcoholic hepatitis. At a cut-off of 4.1 UI/ml, Lam was 90% sensitive and 77% specific, whereas at a cut-off of 150 ng/ml, CIV was 89% sensitive and 77% specific. Combination of markers did not result in improved diagnostic value.
Are serum laminin and type IV collagen accurate markers of histologically severe alcoholic hepatitis in patients with cirrhosis?
10,735,610
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Cocaine and alcohol are frequently used simultaneously and this combination is associated with enhanced toxicity. We recently showed that active cocaine abusers have a markedly enhanced sensitivity to benzodiazepines. Because both benzodiazepines and alcohol facilitate GABAergic neurotransmission we questioned whether cocaine abusers would also have an enhanced sensitivity to alcohol that could contribute to the toxicity. In this study we compared the effects of alcohol (0.75 g/kg) on regional brain glucose metabolism between cocaine abusers (n = 9) and controls (n = 10) using PET and FDG. Alcohol significantly decreased whole brain metabolism and this effect was greater in controls (26+/-6%) than in abusers (17+/-10%) even though they had equivalent levels of alcohol in plasma. Analysis of the regional measures showed that cocaine abusers had a blunted response to alcohol in limbic regions, cingulate gyrus, medial frontal and orbitofrontal cortices.
Do cocaine abusers show a blunted response to alcohol intoxication in limbic brain regions?
10,737,368
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The etiology of interstitial cystitis is unknown. Urine from patients with interstitial cystitis has been shown to inhibit urothelial proliferation through a putative antiproliferative factor and to contain decreased levels of heparin-binding epidermal growth factor-like growth factor (HB-EGF) compared to controls. Stretch of detrusor smooth muscle cells is known to stimulate HB-EGF production. Because bladder hydrodistention sometimes alleviates the symptoms of interstitial cystitis, we determined whether the stretch stimulus of hydrodistention alters antiproliferative factor activity and/or HB-EGF in interstitial cystitis urine specimens. Urine was collected immediately before, and 2 to 4 hours and 2 weeks after hydrodistention from 15 patients with symptoms and cystoscopic findings compatible with interstitial cystitis and 13 controls. Hydrodistention was performed with the subject under general or regional anesthesia and bladders were distended to 80 cm. water 3 times. Urinary HB-EGF was measured by enzyme-linked immunosorbent assay and urinary antiproliferative factor activity was determined by measuring 3H-thymidine uptake by normal human bladder urothelial cells. Hydrodistention significantly increased urinary HB-EGF in patients with interstitial cystitis toward normal control values (before distention p = 0.003, 2 weeks after distention p = 0.67). Urine antiproliferative factor activity decreased significantly after hydrodistention in patients with interstitial cystitis. However, antiproliferative factor activity in interstitial cystitis and control specimens was still statistically different 2 weeks after distention (before distention p = 0.0000004, 2 weeks after distention p = 0.04).
Does bladder stretch alter urinary heparin-binding epidermal growth factor and antiproliferative factor in patients with interstitial cystitis?
10,751,853
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To investigate whether the association between APOE-epsilon4 and memory decline is modified by baseline cognition and age in a population-based elderly sample. The study sample consisted of 1,243 subjects, 62 to 85 years old, with a Mini-Mental State Examination (MMSE) score between 21 and 30 and known APOE phenotypes. Memory performance was measured with an abbreviated Auditory Verbal Learning Test (AVLT) at baseline and repeated after 3 years (n = 854). Memory decline was defined as a decrease of at least 1 SD from the mean change score on immediate recall (IR), delayed recall (DR), and retention, based on the AVLT. Multivariate logistic regression analyses showed that APOE-epsilon4 is associated with memory decline in cognitively impaired subjects (MMSE score, 21 to 26) (OR for decline on IR adjusted for age, sex, education, and baseline recall score, 3.8; 95% CI, 1.4 to 10.0; adjusted OR for decline on DR, 2.9; 95% CI, 1.2 to 7.0; adjusted OR for decline on retention, 3.3; 95% CI, 1.1 to 10. 1), but not in cognitively normal subjects (MMSE score, 27 to 30) (adjusted OR for decline on IR, 1.1; 95% CI, 0.6 to 2.0; adjusted OR for decline on DR, 1.0; 95% CI, 0.6 to 1.8; adjusted OR for decline on retention, 1.5; 95% CI, 0.7 to 3.0). In particular, cognitively impaired epsilon4 carriers older than 75 years were at high risk of memory decline (adjusted OR for decline on IR, 4.5; 95% CI, 1.4 to 13.8; adjusted OR for decline on DR, 3.6; 95% CI, 1.2 to 10.8; adjusted OR for decline on retention, 6.6; 95% CI, 1.5 to 29.7).
Is aPOE-epsilon4 associated with memory decline in cognitively impaired elderly?
10,751,265
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Disruptions to intermyocyte coupling have been implicated in arrhythmogenesis and development of conduction disturbances. At present, understanding of the relationship between the microscopic organization of intercellular coupling and the macroscopic spread of impulse in the normal and diseased heart is largely confined to theoretical analyses. The abundance and arrangement of gap junctions, as well as conduction properties, were assessed in terminal crest preparations isolated from the atria of neonate, weanling, and adult rabbits. We report that the connexin composition of terminal crest was uncomplicated, with Cx43 being the most prominent isoform detectable by Western blotting and immunostaining. Terminal crest myocytes showed little change in total Cx43-gap junction per cell during postnatal growth as assessed by stereology. However, marked non-uniformities emerged in the sarcolemmal distribution of Cx43-gap junctions. Cx43-gap junction area at myocyte termini increased 3.5-fold from birth to adulthood. Correlated with this change in Cx43, impulse propagation velocity parallel to the myofiber axis, as assessed by multi-site optical mapping using voltage-sensitive dye (di-4-ANEPPS), increased 2.4-fold. Conversely, the amount of Cx43-gap junctions on myocyte sides, and the conduction velocity transverse to the myofiber axis, remained relatively invariant during maturation. Hence, the increasing electrical anisotropy of maturing terminal crest was wholly accounted for by increases in conductance velocity along the bundle. This increase in longitudinal conduction velocity was correlated with changes in the sarcolemmal pattern, but not the overall density, of Cx43-gap junctions.
Are the rate and anisotropy of impulse propagation in the postnatal terminal crest correlated with remodeling of Cx43 gap junction pattern?
10,728,358
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Hypercontracture is an important mechanism of myocyte death during reperfusion. cGMP modulates the sensitivity of contractile myofilaments to Ca2+, and increasing cGMP concentration during the last minutes of anoxia prevents reoxygenation-induced hypercontracture in isolated cardiomyocytes. The purpose of this study was to determine whether stimulation of particulate guanylyl cyclase with the natriuretic peptide urodilatin, given at the time of reperfusion, reduces myocardial necrosis in the rat heart submitted to transient ischemia. Isolated rat hearts (n = 38) were submitted to either 40 or 60 min of no-flow ischemia and 2 h of reperfusion, and were allocated to receive or not receive 0.05 microM urodilatin during the first 15 min of reperfusion or non-reperfusion treatment. A marked reduction in myocardial cGMP concentration was observed in control hearts during reperfusion after 40 or 60 min of ischemia. Urodilatin significantly attenuated cGMP depletion during initial reperfusion, markedly improved contractile recovery after 40 min of ischemia (P < 0.0309), and reduced reperfusion-induced increase in left ventricular end-diastolic pressure (P = 0.0139), LDH release (P = 0.0263), and contraction band necrosis (P = 0.0179) after 60 min of ischemia. The beneficial effect of urodilatin was reproduced by the membrane permeable cGMP analog 8-Bromo-cGMP.
Does urodilatin limit acute reperfusion injury in the isolated rat heart?
10,728,355
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Diminishing oxidative stress may protect the heart against ischaemia-reperfusion injury by preventing opening of the mitochondrial permeability transition (MPT) pore. The general anaesthetic agent propofol, a free radical scavenger, has been investigated for its effect on the MPT and its cardioprotective action following global and cardioplegic ischaemic arrest. Isolated perfused Wistar rat hearts were subjected to either warm global ischaemia (Langendorff) or cold St. Thomas' cardioplegia (working heart mode) in the presence or absence of propofol. MPT pore opening was determined using [3H]-2-deoxyglucose-6-phosphate ([3H]-DOG-6P) entrapment. The respiratory function of isolated mitochondria was also determined for evidence of oxidative stress. Propofol (2 micrograms/ml) significantly improved the functional recovery of Langendorff hearts on reperfusion (left ventricular developed pressure from 28.4 +/- 6.2 to 53.3 +/- 7.3 mmHg and left ventricular end diastolic pressure from 52.9 +/- 4.3 to 37.5 +/- 3.9 mmHg). Recovery was also improved in propofol (4 micrograms/ml) treated working hearts following cold cardioplegic arrest. External cardiac work on reperfusion improved from 0.42 +/- 0.05 to 0.60 +/- 0.03 J/s, representing 45-64% of baseline values, when compared to controls (P < 0.05). Propofol inhibited MPT pore opening during reperfusion, [3H]-DOG-6P entrapment being 16.7 vs. 22.5 ratio units in controls (P < 0.05). Mitochondria isolated from non-ischaemic, propofol-treated hearts exhibited increased respiratory chain activity and were less sensitive to calcium-induced MPT pore opening.
Is protection of hearts from reperfusion injury by propofol associated with inhibition of the mitochondrial permeability transition?
10,728,356
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Japanese in-patients with pulmonary tuberculosis and normal liver function receiving treatment with isoniazid and rifampicin (INH + RMP). To elucidate the relationship between N-acetyltransferase 2 (NAT2) genotype and the incidence of isoniazid + rifampicin-induced hepatotoxicity. Prospective study. After NAT2* genotyping, 77 patients were classified into three groups according to their NAT2* genotypes: rapid-type (a homozygote of NAT2*4), intermediate-type (a heterozygote of NAT2*4 and mutant alleles) and slow-type (a combination of mutant alleles). Their biochemical profiles of liver function test were investigated for 3 months to assess the development of serum aminotransferase elevation. Of the 77 patients, 18.2% developed adverse hepatic reaction within the first month of INH + RMP treatment. A significant association was observed between hepatotoxicity and NAT2* genotype: compared with rapid-type, the relative risk was 4.0 (95% CI 1.94-6.06) for intermediate-type and 28.0 (95%CI 26.0-30.0) for slow-type. Especially in slow-type, the incidence of hepatotoxicity and serum aminotransferase elevation was significantly higher than in the other two types.
Does slow N-acetyltransferase 2 genotype affect the incidence of isoniazid and rifampicin-induced hepatotoxicity?
10,751,073
{ "answer_start": [ -1 ], "text": [ "yes" ] }
We sought to determine whether abciximab therapy at the time of percutaneous coronary intervention (PCI) would favorably affect one-year mortality in patients with diabetes. Diabetics are known to have increased late mortality following PCI. Data from three placebo-controlled trials of PCI, EPIC, EPILOG, and EPISTENT, were pooled. The one-year mortality rate for patients with a clinical diagnosis of diabetes mellitus was compared with the rate for nondiabetic patients treated with either abciximab or placebo. In the 1,462 diabetic patients, abciximab decreased the mortality from 4.5% to 2.5%, p = 0.031, and in the 5,072 nondiabetic patients, from 2.6% to 1.9%, p = 0.099. In patients with the clinical syndrome of insulin resistance--defined as diabetes, hypertension, and obesity--mortality was reduced by abciximab treatment from 5.1% to 2.3%, p = 0.044. The beneficial reduction in mortality with abciximab use in diabetics classified as insulin-requiring was from 8.1% to 4.2%, p = 0.073. Mortality in diabetics who underwent multivessel intervention was reduced from 7.7% to 0.9% with use of abciximab, p = 0.018. In a Cox proportional hazards survival model, the risk ratio for mortality with abciximab use compared with placebo was 0.642 (95% confidence interval 0.458-0.900, p = 0.010).
Does abciximab reduce mortality in diabetics following percutaneous coronary intervention?
10,732,889
{ "answer_start": [ -1 ], "text": [ "yes" ] }
All known pathways of ethanol metabolism result in the production of acetaldehyde, a highly reactive compound. Acetaldehyde has been shown to deplete vitamin B6 in chronic alcoholics. It also binds with sulfhydryl groups of membrane proteins, altering membrane Ca2+ channels and increasing vascular cytosolic free calcium, peripheral vascular resistance and blood pressure. The aldehyde-binding thiol compound, N-acetyl cysteine, attenuates elevated blood pressure and associated adverse changes in ethanol-induced hypertensive rats. Vitamin B6 supplementation increases the level of endogenous cysteine. Aim of this work was thus to investigate whether a dietary supplementation of vitamin B6 can prevent ethanol-induced hypertension and associated changes in Wistar-Kyoto (WKY) rats. Starting at 7 weeks of age, WKY rats were divided into three groups of six animals each. The control group received a normal vitamin B6 diet (regular chow) and normal drinking water, the ethanol group, the same diet plus 1% ethanol in the drinking water, and the ethanol + vitamin B6 group a high vitamin B6 diet (20 times normal diet) and 1% ethanol in the drinking water. After 14 weeks, systolic blood pressure, platelet [Ca2+]i and kidney and aortic aldehyde conjugate levels were significantly higher in the ethanol group. These rats also showed smooth muscle cell hyperplasia in the small arteries and arterioles of the kidneys. Dietary vitamin B6 supplementation prevented these changes.
Does dietary vitamin B6 supplementation prevent ethanol-induced hypertension in rats?
10,726,110
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The anti-inflammatory effect of low-dose radiotherapy (LD-RT) still is not understood. The adhesion of leukocytes to endothelial cells (EC) of the vessel wall is the initial event of tissue invasion, and thus, crucially contributes to the regulation of inflammation. We investigated the influence of LD-RT on the adhesion process in vitro. Isolated peripheral-blood-mononuclear-cells (PBMC) were incubated with an activated murine endothelioma cell-line under shear conditions at 4 degrees C after irradiation with single doses between 0.1 and 10.0 Gy. Adherent cells were counted microscopically and compared to a non-irradiated control. In parallel, viability and expression of adhesion molecules, especially of L-selectin, and lineage-specific markers on the cell surface were determined by dye exclusion and cytofluorometry, respectively. Modulation of adhesion by soluble L-selectin was tested in the adhesion assay. Radiation doses of 0.1-0.5 Gy reduced the adhesion of viable PBMC to EC in vitro by 70% of the control level 4 h after irradiation. Leukocytes showed a marked reduction of L-selectin expression after LD-RT. Soluble L-selectin can inhibit the adhesion of PBMC to EC.
Does low-dose radiotherapy selectively reduce adhesion of peripheral blood mononuclear cells to endothelium in vitro?
10,738,086
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Recovery to normal or near normal visual acuity is usual after acute demyelinating optic neuritis, despite the frequent persistence of conduction abnormalities as evidenced by the visual evoked potential (VEP). This raises the possibility that cortical adaptation to a persistently abnormal input contributes to the recovery process. The objective of this study was to investigate the pattern of cerebral response to a simple visual stimulus in recovered patients in comparison to normal subjects. Functional magnetic resonance imaging (fMRI) was used to study the brain activation pattern induced by a periodic monocular 8Hz photic stimulus in seven patients who had recovered from a single episode of acute unilateral optic neuritis, and in seven normal controls. VEPs and structural optic nerve MRI were performed on patients. Stimulation of either eye in controls activated only the occipital visual cortex. However, in patients, stimulation of the recovered eye also induced extensive activation in other areas including the insula-claustrum, lateral temporal and posterior parietal cortices, and thalamus; stimulation of the clinically unaffected eye activated visual cortex and right insula-claustrum only. The volume of extraoccipital activation in patients was strongly correlated with VEP latency (r = 0.71, p = 0.005).
Is recovery from optic neuritis associated with a change in the distribution of cerebral response to visual stimulation : a functional magnetic resonance imaging study?
10,727,479
{ "answer_start": [ -1 ], "text": [ "yes" ] }
An intact and fully functional multiprotein DNA replication complex (DNA synthesome) from human as well as from murine mammary carcinoma cells was first isolated and characterized in our laboratory. The human cell synthesome supports the in vitro origin-specific simian virus 40 (SV40) DNA replication reaction in the presence of the viral large T-antigen using a semiconservative mechanism and has been shown to contain all the proteins and enzymes required to support DNA synthesis. We are currently using the DNA synthesome as a unique model for analyzing the mechanism of action of anticancer drugs affecting DNA replication. The purpose of this study was to further investigate the mechanism of action of ara-C using the DNA synthesome isolated from the human breast cancer cell line MDA MB-468. Synthesome-mediated SV40 DNA replication was performed in the presence of various concentrations of ara-CTP (the active metabolite of ara-C) and the types of daughter DNA molecules produced were analyzed lusing neutral and alkaline gel electrophoresis. We also examined the effect of ara-C on intact MDA MB-468 cell DNA synthesis and on cell proliferation. In addition, we studied the effect of ara-CTP on the activity of some of the synthesome target proteins (the DNA polymerases alpha and delta). Full-length daughter DNA molecules were obtained in the presence of low concentrations of ara-CTP while at higher concentrations, there was an inhibition of full-length daughter DNA synthesis. The findings suggest that specifically the initiation phase of DNA synthesis was inhibited by ara-CTP since the production of the short Okazaki fragments was suppressed at all concentrations of the drug above 10 microM. In addition, it was found that the IC50 of ara-CTP for inhibition of synthesome-mediated in vitro DNA replication was comparable to that required to inhibit intact cell DNA synthesis. Further experimentation has shown that ara-CTP preferentially inhibits the activity of the synthesome-associated DNA polymerase alpha enzyme while the DNA polymerase delta seems to be resistant to the inhibitory effect of that drug.
Does ara-C affect formation of cancer cell DNA synthesome replication intermediates?
10,755,320
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To investigate the early stages in the formation of bony spurs in relation to normal enthesis development. Histologic sections of rat Achilles tendons, stained with toluidine blue or Masson's trichrome, were examined in animals ranging from 2 weeks to 1 year of age. Further material prepared for immunohistochemistry was labeled with monoclonal antibodies for laminin and type IV collagen to highlight the presence of small blood vessels at the enthesis. Sections of small spurs from the Achilles tendons of elderly humans were also examined for comparison. As a part of normal development, bone grows into the Achilles tendon as the calcaneus enlarges. Ossification is preceded by vascular invasion, which occurs along rows of enthesis fibrocartilage cells. Small bony spurs develop when ossification at one point on the enthesis outstrips that on either side.
Does the mechanism of formation of bony spur ( enthesophytes ) in the achilles tendon?
10,728,751
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Increased oxidative stress and myocyte apoptosis co-exist in the remote non-infarcted myocardium (RM) following a large myocardial infarction. We proposed that these phenomena are causally related. On day 3 after induction of myocardial infarction, Sprague-Dawley rats were randomized to receive probucol and pyrrolidine dithiocarbamate (MI-T), or vehicle only (MI) for 7 weeks. Control rats (C) received vehicle. At 7 weeks, lipidperoxidation within the RM was assessed by measuring thiobarbituric acid reactive substances, which were significantly increased in MI vs. C, while MI-T was not different from C. There was a significant increase in cardiac myocytes positive for in situ TdT-UTP nick-end labeling within the RM in MI vs. C, which was inhibited in MI-T. Furthermore, internucleosomal DNA fragmentation was clearly demonstrated on agarose gels from RM in the MI group, while it was much less apparent on gels from RM in the C and MI-T groups. Western blot analysis showed a significant increase in p53, Bax and caspase-3 protein expression within the RM of MI vs. C, all of which were inhibited in the MI-T group. Furthermore, there was evidence for an increase in caspase-3 activity within the RM from MI vs. C, which was normalized in the MI-T group.
Do antioxidants attenuate myocyte apoptosis in the remote non-infarcted myocardium following large myocardial infarction?
10,728,389
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Apoptosis of cardiomyocytes may contribute to ischemia-reperfusion injury. The role of nitric oxide (NO) in apoptosis is controversial. Therefore, we investigated the effect of NO synthase inhibition on apoptosis of cardiomyocytes during ischemia and reperfusion and elucidated the underlying mechanisms. Isolated perfused rat hearts (n = 6/group) were subjected to ischemia (30 min) and reperfusion (30 min) in the presence or absence of the NO synthase inhibitor NG-mono-methyl-L-arginine. Reperfusion induced cardiomyocyte apoptosis as assessed by immunohistochemistry (TUNEL-staining) and the demonstration of the typical DNA laddering. Apoptosis during reperfusion was associated with the cleavage of caspase-3, the final down-stream executioner caspase, whereas the protein levels of the anti-apoptotic protein Bcl-2 and the pro-apoptotic protein Bax were unchanged. Inhibition of the NO synthase drastically increased ischemia and reperfusion-induced apoptosis of cardiomyocytes. Moreover, the NO synthase inhibitor enhanced the activation of caspase-3, suggesting that NO interferes with the activation of caspases in ischemia-reperfusion.
Does inhibition of endogenous nitric oxide synthase potentiate ischemia-reperfusion-induced myocardial apoptosis via a caspase-3 dependent pathway?
10,728,388
{ "answer_start": [ -1 ], "text": [ "yes" ] }
It has been demonstrated that tumor necrosis factor-alpha (TNF alpha) induces apoptosis in cardiac myocytes. However, its mechanism of action is still not well understood. In the present study, we hypothesized that TNF alpha induces myocardial apoptosis by induction of inducible nitric oxide synthase (iNOS). Neonatal cardiac myocytes were isolated from iNOS (-/-) mutant and C57BL6 wild type mice. Cells were cultured for 3 days before treatment with an NO donor or TNF alpha. Following treatment with S-nitroso-N-acetyl-penicillamine (SNAP) or TNF-alpha, cells were tested for apoptosis by terminal deoxynucleotidyl transfer-mediated end labeling (TUNEL) staining and cell death detection ELISA. NO production was measured by nitrite concentration in the culture medium. Cardiomyocyte expression of iNOS and TNF type 1 receptor (TNFR1) mRNA was determined by reverse transcriptase-polymerase chain reaction (RT-PCR). SNAP (0.01-100 microM) induced apoptosis of cardiac myocytes in a concentration-dependent manner in the wild type mice (n = 5, P < 0.01). TNFR1 mRNA was expressed in neonatal cardiomyocytes from both wild type and iNOS (-/-) mutant mice. TNF alpha induced a concentration-dependent increase in iNOS mRNA expression and nitrite production as well as significant apoptosis of cardiomyocytes in the wild type mice (n = 4, P < 0.01). However, without iNOS expression, the apoptotic effects of TNF-alpha were significantly attenuated in cardiomyocytes from iNOS (-/-) mutant mice (n = 4, P < 0.05).
Does tumor necrosis factor-alpha induce apoptosis via inducible nitric oxide synthase in neonatal mouse cardiomyocytes?
10,728,381
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Blood-epithelial barriers have been described in the testis and epididymis, but the possibility of such barriers in other regions of the male genitourinary tract has received little investigation. The purpose of this study was to use in vivo micro-puncture to determine if the blood-epithelial barrier exists in the rat ventral prostate. In addition, using a model of prostatic inflammation, we sought to examine the effect of inflammation on the passage of blood borne molecules and leukocytes into the prostatic ductal lumen. Adult Sprague-Dawley rats were divided into two groups, control and 24-hour lipopolysaccharide (LPS)-induced inflammation. Both groups were subjected to vascular infusion of radiolabeled 3H dextran, 14C urea, and 3H water. Contemporaneous in vivo micropuncture sampling of prostatic ductal fluid (DF) and arterial blood occurred at multiple time points over 120 minutes. Transepithelial movement of radiolabeled compounds at each sampling time point was quantified by the expression of DF isotope concentrations as a percentage of serum isotope concentrations at that time point. Histology of representative specimens of control and inflamed prostates was used to confirm the inflammatory response and to examine for the presence of leukocytes into the ductal lumen. The transepithelial movement of radiolabeled compounds from blood to prostatic lumen varied in direct relationship to the compound's molecular weight. 3H-water (MW = 18) movement into the ductal lumina was relatively rapid plateauing at 70-80% of serum values. 14C urea (MW = 60) achieved intermediate penetration into ductal fluid (50-60% of serum values) and 3H dextran (MW = 2 x 106) was essentially excluded from entry (<2% of serum). These results were not altered by LPS-induced inflammation. Histology revealed a diffuse leukocyte infiltrate in the inflamed prostatic interstitium, but penetration of inflammatory cells into the ductal lumen was very restricted.
Does a blood-prostate barrier restrict cell and molecular movement across the rat ventral prostate epithelium?
10,751,894
{ "answer_start": [ -1 ], "text": [ "yes" ] }
We examined whether heparin-coated (HC) circuits can improve the operative results in patients with chronic renal insufficiency. Elective cardiac surgery was performed in 24 patients with a serum creatinine (Cr) level of at least 1.5 mg/dl. Uncoated circuits were used in 12 patients, and HC circuits were used in 12 patients. The results of surgery were compared between the two groups. The mean preoperative Cr concentration was significantly higher in the HC group (2.3 vs 1.8 mg/dl). The heparin doses, protamine dose, and activated clotting times were significantly lower in the HC group. The mean blood loss was also less, although this difference was not significant. The postoperative increase in the Cr level was small in the HC group (2.3-->2.5 mg/dl) compared to that in the noncoated group (1.8-->2.3 mg/dl). Postoperative dialysis was not required in the 5 patients in the HC group with a preoperative Cr clearance less than 20 ml/min.
Do heparin-coated circuits prevent renal dysfunction after open heart surgery?
10,730,081
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Sildenafil (Viagra), an oral treatment for erectile dysfunction, has proved popular since its introduction in 1998. However, not all patients respond to this form of therapy. Consequently, this study investigated the efficacy of intracavernous alprostadil alfadex (EDEX/VIRIDAL) treatment in patients not responding to sildenafil. In an open-label, multicenter study, patients with erectile dysfunction were treated with sildenafil for 4 weeks. The initial dose was 50 mg, which was increased to 100 mg if no response was achieved. Patients not responding to treatment, measured using the International Index of Erectile Function (IIEF) questionnaire, entered an alprostadil alfadex in-office titration phase, to determine the optimal dose, up to 40 microgram. A 6-week alprostadil alfadex at-home treatment phase followed. In 67 patients who did not respond satisfactorily to sildenafil, the alprostadil alfadex at-home therapy resulted in improvements in questions 3 and 4 of the IIEF in 60 (89.6%) and 57 (85.1%) patients, respectively. The mean improvement in IIEF score for these patients was 2.75 and 2.63 for questions 3 and 4, respectively. The most common side effect was penile pain in 25 (29. 4%) of 85 patients treated with alprostadil alfadex in-office and at home.
Is intracavernous alprostadil alfadex ( EDEX/VIRIDAL ) effective and safe in patients with erectile dysfunction after failing sildenafil ( Viagra )?
10,736,486
{ "answer_start": [ -1 ], "text": [ "yes" ] }
To study the pathophysiological importance of changes in insulin sensitivity and islet function over time for alterations in glucose tolerance in a randomly selected large group of non-diabetic women aged 57-59 years over a 3-year period. At baseline and at the 3-year follow-up, glucose tolerance (WHO 75 g oral glucose), insulin sensitivity (euglycaemic, hyperinsulinaemic clamp) and insulin and glucagon secretion (2 to 5-min responses to 5 g i.v. arginine at fasting, 14 and > 25 mmol/l glucose) were measured. At baseline, women with impaired glucose tolerance (IGT, n = 28) had lower insulin sensitivity (p = 0.048) than normal women (NGT, n = 58). The arginine-induced insulin responses (AIR) were inversely associated with insulin sensitivity (r > or = -0.55, p < 0.001). When related to the 3-year follow-up, the baseline product of AIR at 14 mmol/l glucose times insulin sensitivity, insulin effect index (IE) (r = -0.40, p < 0.001) and the arginine-induced glucagon response at 14 mmol/l glucose (AGR, r = 0.28, p = 0.009) both correlated with follow-up 2-h glucose. In a multiple regression model, baseline 2-h glucose, insulin effect index and arginine-induced glucagon response independently predicted 2-h glucose at follow-up (total r = 0.668, p < 0.001). Furthermore, delta insulin sensitivity (i. e. follow-up minus baseline) correlated with delta insulin secretion (r = -0.30, p = 0.006), whereas delta glucagon secretion correlated with delta2-h glucose (r = 0.30, p = 0.006) over the 3 years. In a multiple regression, alterations in 2-h glucose over the 3 years were independently determined by changes in fasting insulin and glucagon secretion (r = 0.424, p < 0.001).
Is glucose intolerance predicted by low insulin secretion and high glucagon secretion : outcome of a prospective study in postmenopausal Caucasian women?
10,753,041
{ "answer_start": [ -1 ], "text": [ "yes" ] }
In obese French Caucasian subjects we previously described a silent UCP3 Tyr99Tyr mutation, associated with body mass index. We hypothesised that an unknown polymorphism in the vicinity of the gene could contribute to obesity. Morbidly obese subjects were screened for mutations in 1 kb upstream from the UCP3 gene. Association studies were done between a variant and obesity in 401 morbidly obese and 231 control subjects. We detected three rare genetic variants and one polymorphism: a +5 G-->A in exon 1, a -155 C-->T, a -439 A insertion and a -55 C-->T located 6 bp from the putative TATA box. This variant was in linkage disequilibrium with the Tyr99Tyr polymorphism. Frequencies of the variant allele at the -55 locus were similar in the obese and control groups (0.23 vs 0.21). The -55 polymorphism was associated with BMI in the obese group (p = 0.0031): BMI was higher in TT than in CC or CT patients. Likewise control subjects with a TT genotype had a higher BMI (p = 0.03). In the obese group, homozygosity for this variant is a risk factor for high BMI (odds ratio: 1:75, p = 0.02). Obese patients were divided into tertiles according to physical activity. In the group with a wild C/C genotype, BMI was negatively associated with physical activity (p = 0.015).
Is a genetic variation in the 5 ' flanking region of the UCP3 gene associated with body mass index in humans in interaction with physical activity?
10,753,049
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Lipopolysaccharide (LPS) is closely associated with the development of infection-induced deleterious pulmonary reactions. In this study, we investigated the enhancement effects of LPS on tachykinin-mediated plasma exudation in the lungs of guinea pigs. The role of oxidants was also explored. Intravenous LPS (100 mu kg-1) or its vehicle was administered 0 to 3 hours prior to bilateral electrical or sham stimulation of the cervical vagus nerves in animals anesthetized with urethane and artificially ventilated. Plasma exudation into the lungs was assessed by measurement of extravasated 125I-albumin which had been intravenously administered before stimulation. The plasma exudation in the lungs increased after bilateral cervical vagal stimulation. LPS alone did not induce significant plasma exudation. The vagally-mediated plasma exudation was enhanced by LPS with the peak effect 1 hour after LPS administration. LPS also enhanced exogenous substance P (10(-8) mol kg-1, i.v.)-induced plasma exudation. The vagally-induced plasma exudation was abolished by a specific neurokinin-1 (NK-1) receptor antagonist, L-732,138. The LPS-induced enhancement response was also attenuated by L-732,138. The vagally-induced plasma exudation was not affected by superoxide dismutase (SOD, 5000 U kg-1, i.p.) pretreatment. However, SOD significantly inhibited the LPS-enhanced neurogenic plasma leakage. The LPS-induced enhancement was not completely abolished by either L-732,138 or SOD pretreatment alone, but by a combination of both.
Does endotoxemia augment neurogenic plasma exudation in guinea pig lungs?
10,746,405
{ "answer_start": [ -1 ], "text": [ "yes" ] }
The aim of this study was the measurement of maternal serum levels of M-CSF throughout pregnancy, in a low risk obstetrical population, to examine the relationship of M-CSF and pregnancy outcome. Maternal serum was obtained at various stages of pregnancy and post partum, M-CSF levels were measured by ELISA, pertinent clinical data tabulated, and pregnancy outcome was determined. In 564 pregnancies studied, 22% of 260 nulliparous pregnancies and 10% of 304 multiparous pregnancies were hypertensive. Preeclampsia occurred in 1.5% of nulliparous and in 1% of the multiparous women. In apparently normal pregnancies with good outcome, M-CSF levels rose throughout pregnancy. No cases of preeclampsia occurred if maternal serum M-CSF levels increased more than 100% throughout pregnancy.
Are maternal serum levels of macrophage colony-stimulating factor associated with adverse pregnancy outcome?
10,733,019
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Interleukin-8 (IL-8), a CXC chemokine that induces the migration and proliferation of endothelial cells and smooth muscle cells, is a potent angiogenic factor that may play a role in atherosclerosis. Previously, IL-8 has been reported in atherosclerotic lesions and circulating macrophages from patients with atherosclerosis. Therefore, we sought to determine whether IL-8 plays a role in mediating angiogenic activity in atherosclerosis. Homogenates from 16 patients undergoing directional coronary atherectomy (DCA) and control samples from the internal mammary artery (IMA) of 7 patients undergoing bypass graft surgery were assessed for IL-8 content by specific ELISA, immunohistochemistry, and in situ hybridization for IL-8 mRNA. The contribution of IL-8 to net angiogenic activity was assessed using the rat cornea micropocket assay and cultured cells. IL-8 expression was significantly elevated in DCA samples compared with IMA samples (1.71+/-0.6 versus 0.05+/-0.03 ng/mg of total protein; P<0.01). Positive immunolocalization of IL-8 was found exclusively in DCA tissue sections, and it correlated with the presence of factor VIII-related antigen. In situ reverse transcriptase polymerase chain reaction revealed the expression of IL-8 mRNA in DCA tissue. Corneal neovascular response, defined by ingrowth of capillary sprouts toward the implant, was markedly positive with DCA pellets, but no constitutive vessel ingrowth was seen with IMA specimens. Neutralizing IL-8 attenuated both the in vivo corneal neovascular response and the in vitro proliferation of cultured cells.
Is iL-8 an angiogenic factor in human coronary atherectomy tissue?
10,747,344
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Rapid ventricular pacing produces a reliable model of heart failure. Cessation after 4 weeks of rapid ventricular pacing results in rapid normalization of left ventricular function, but the left ventricle remains persistently dilated. We present novel data that show that prolonged rapid ventricular pacing (10 weeks) creates a model of chronic left ventricular dysfunction. In 9 dogs undergoing 10 weeks of rapid ventricular pacing, left ventricular function and volumes were serially assessed by using 2-dimensional echocardiography and pressure-volume analysis for 12 weeks after cessation of pacing. Increased end-diastolic volume and decreased systolic and diastolic function were seen at the end of pacing. By 2 weeks of recovery from rapid ventricular pacing, end-diastolic volume and ejection fraction were partially recovered but did not improve further thereafter. Load-independent and load-sensitive indices of function obtained by pressure-volume analysis at 8 and 12 weeks of recovery confirmed a persistence of both systolic and diastolic dysfunction. In addition, left ventricular mass increased with pacing and remained elevated at 8 and 12 weeks of recovery. Four of these dogs studied at 6 months of recovery showed similar left ventricular abnormalities.
Does ten weeks of rapid ventricular pacing create a long-term model of left ventricular dysfunction?
10,733,777
{ "answer_start": [ -1 ], "text": [ "yes" ] }
A reversible contractile dysfunction without necrosis after transient myocardial ischemia has been termed stunning. The molecular mechanisms underlying this phenomenon are only now beginning to be unraveled. It is conceivable that the expression of early-response genes may play a crucial role in stunning. The expression of HSP-70, c-jun, and GRP-94 was investigated in a chronically instrumented dog model (n = 9). The left anterior descending coronary artery was occluded temporarily for 10 minutes after the animals had fully recovered from instrumentation. The wall thickening fraction was measured in the left anterior descending coronary artery and the nonischemic ramus circumflex of the left coronary artery-perfused region. When the wall thickening fraction of the left anterior descending coronary artery had recovered to 50% of preocclusion values, tissue samples were obtained from the areas perfused by the left anterior descending coronary artery and the nonischemic ramus circumflex of the left coronary artery. The messenger RNA of HSP-70 was increased to 214% +/- 26% in the area perfused by the left anterior descending artery compared with that perfused by the nonischemic ramus circumflex of the left coronary artery. There was no difference in the messenger RNA of GRP-94. The HSP-70 content was elevated to 130% +/- 14% in the left anterior descending artery compared with the area perfused by the ramus circumflex of the left coronary artery, and the c-jun protein content was 70% +/- 25% higher in the ischemic area compared with the control area.
Are the early response genes c-jun and HSP-70 induced in regional cardiac stunning in conscious mammals?
10,733,775
{ "answer_start": [ -1 ], "text": [ "yes" ] }
Our objective was to determine whether paclitaxel-induced apoptosis in human lung cancer cells is Fas dependent. Human lung cancer cell lines were evaluated for morphologic evidence of apoptosis, DNA fragmentation (TUNEL positivity), and caspase-3 activation after paclitaxel treatment. Human lung adenocarcinoma, squamous cell carcinoma, undifferentiated lung carcinoma, and bronchoalveolar carcinoma cell lines were each cultured in 10 micromol/L paclitaxel. After 24 hours of culture in paclitaxel, a 22% to 69% increase in the number of apoptotic cells was evident by means of methylene blue-azure A-eosin staining with characteristic blebbing and nuclear condensation. TUNEL assay also confirmed an increase of 19.9% to 73.0% of cells with nuclear fragmentation. Caspase-3 activity, assayed by Z-DEVD cleavage, increased from 20% to 215% (P <.05). ZB4, an antagonistic anti-Fas antibody, did not block paclitaxel induction of caspase-3 activity (155.8 vs 165.8 U, not significant). Apoptotic morphologic changes were inhibited in cells cultured in the presence of paclitaxel and Ac-DEVD-CHO, a caspase-3 inhibitor.
Is paclitaxel-induced apoptosis in non-small cell lung cancer cell lines associated with increased caspase-3 activity?
10,733,772
{ "answer_start": [ -1 ], "text": [ "yes" ] }