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Richard Ila  Michele Solem 《Alcohol》2006,39(3):169-178
Previously, we have demonstrated that chronic-alcohol exposure alters insulin-like growth factor 1 (IGF1) signaling in adult rat heart cells. This report examines the effects of alcohol in vitro on the expression of protein kinase C (PKC) alpha, delta, and epsilon using the embryonic heart cell line, H9c2, and how this may be linked to changes in IGF1 signal transduction. Western blot analyses of H9c2 protein preparations demonstrate that there are significant increases in the total protein levels of PKC delta and epsilon after 4 days exposure to alcohol, and similar increases were found after 2 and 6 days exposure. In addition, there was a significant increase in PKC delta and epsilon in the membranal fractions and a decrease in the cytosolic fractions. No change was found in the expression or activity levels for PKC alpha. Chronic-alcohol exposure (100 mM, 4 days) increased the basal tyrosine kinase activity of the IGF1 receptor (IGF1R), and altered its rate of activation. Chronic-alcohol exposure also reduced the rate of Erk1/Erk2 activation by IGF1. Chronic alcohol blocked the proliferative effects of IGF1 on cell growth and reduced cell viability both in the presence and absence of IGF1, and this alcohol-induced reduction in cell viability was blocked using siRNA to inhibit PKC delta. In addition, a reduction in the amount of myosin light chain 2 was found in the alcohol-exposed cells. In conclusion, chronic alcohol alters PKC delta and epsilon expression and activity, and suppresses the IGF1 signaling pathway in embryonic heart cell culture. Blockage of PKC delta expression using siRNA inhibits the suppressive effects of alcohol on cell viability.  相似文献   
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This communication presents an 11-center prospective randomized trial using the artificial dermis invented by Burke and Yannas. Patients with life-threatening burns who underwent primary excision and grafting within 7 days of injury had comparable sites randomized to receive either the artificial dermis (study site) or the investigator's usual skin grafting material (control site). Control materials were autograft, allograft, xenograft, or a synthetic dressing. Epidermal grafts were applied to the study site during a second operation, and surviving patients were followed for 1 year after grafting. One hundred thirty-nine sites on 106 patients were studied. Mean burn size was 46.5 +/- 15% mean total body surface (TBSA). Overall mortality was 13%, and mean hospital stay was 68 +/- 45 days. Median artificial dermis take was 80% compared with 95% for all comparative sites, but the take was equivalent to that of all nonautograft control materials. Results with the artificial dermis improved slightly as the investigators became more familiar with the material. Donor site thickness for the study site averaged .006' +/- .002' compared to .013' +/- .018' for control (p less than .0001) and the epidermal donor site healed an average of 4 days sooner (10 +/- 6 vs. 14 +/- 8 days) (p less than .0001). As the wounds matured during the first year, both patients and surgeons felt that both sites became more comparable in appearance and function. At the completion of the study, there was less hypertrophic scarring of the artificial dermis, and more patients preferred the artificial dermis to the control graft. Artificial dermis with an epidermal graft provides a permanent cover that is at least as satisfactory as currently available skin grafting techniques, and uses donor grafts that are thinner and donor sites that heal faster.  相似文献   
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Polyomavirus BK (BKV) causes polyomavirus-associated nephropathy (PyVAN) and hemorrhagic cystitis (PyVHC) in renal and bone marrow transplant patients, respectively. Antiviral drugs with targeted activity against BKV are lacking. Since the antimalarial drug artesunate was recently demonstrated to have antiviral activity, the possible effects of artesunate on BKV replication in human primary renal proximal tubular epithelial cells (RPTECs), the host cells in PyVAN, were explored. At 2 h postinfection (hpi), RPTECs were treated with artesunate at concentrations ranging from 0.3 to 80 μM. After one viral replication cycle (approximately 72 hpi), the loads of extracellular BKV DNA, reflecting viral progeny production, were reduced in a concentration-dependent manner. Artesunate at 10 μM reduced the extracellular BKV load by 65%; early large T antigen mRNA and protein expression by 30% and 75%, respectively; DNA replication by 73%; and late VP1 mRNA and protein expression by 47% and 64%, respectively. Importantly, the proliferation of RPTECs was also inhibited in a concentration-dependent manner. At 72 hpi, artesunate at 10 μM reduced cellular DNA replication by 68% and total metabolic activity by 47%. Cell impedance and lactate dehydrogenase measurements indicated a cytostatic but not a cytotoxic mechanism. Flow cytometry and 5-ethynyl-2′-deoxyuridine incorporation revealed a decreased number of cells in S phase and suggested cell cycle arrest in G0 or G2 phase. Both the antiproliferative and antiviral effects of artesunate at 10 μM were reversible. Thus, artesunate inhibits BKV replication in RPTECs in a concentration-dependent manner by inhibiting BKV gene expression and genome replication. The antiviral mechanism appears to be closely connected to cytostatic effects on the host cell, underscoring the dependence of BKV on host cell proliferative functions.  相似文献   
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INTRODUCTION: We sought to examine the relationship between C-reactive protein (CRP) and clinical, endoscopic, histologic, and radiographic activity in inflammatory bowel disease (IBD). METHODS: All IBD patients at our institution between January 2002 and August 2003 who had a CRP, colonoscopy, and either small bowel follow-through (SBFT) or CT enterography (CTE) performed within 14 days were identified. Clinical activity was assessed retrospectively through review of the medical record. Logistic regression was used in Crohn's disease (CD) patients to estimate the odds ratio (OR) with 95% confidence intervals for an elevated CRP. Associations were assessed using Fisher exact test in ulcerative colitis (UC) patients due to small sample size. RESULTS: One-hundred four CD patients (46% males) and 43 UC and indeterminate colitis patients (44% males) were identified. In CD patients, moderate-severe clinical activity (OR, 4.5; 95% CI, 1.1-18.3), active disease at colonoscopy (OR, 3.5; 95% CI, 1.4-8.9), and histologically severe inflammation (OR, 10.6; 95% CI; 1.1-104) were all significantly associated with CRP elevation. Abnormal small bowel radiographic imaging was not significantly associated with CRP elevation. In UC patients, CRP elevation was significantly associated with severe clinical activity, elevation in sedimentation rate, anemia, hypoalbuminemia, and active disease at ileocolonoscopy, but not with histologic inflammation. CONCLUSIONS: CRP elevation in IBD patients is associated with clinical disease activity, endoscopic inflammation, severely active histologic inflammation (in CD patients), and several other biomarkers of inflammation, but not with radiographic activity.  相似文献   
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BACKGROUND: To assess health-related quality of life (HRQOL) in patients after cardiac surgery with emphasis on sex differences. DESIGN AND METHODS: Between September 2004 and September 2005, 534 patients (413 males and 121 females) were consecutively included. HRQOL was measured by the short-form 36 (SF-36) before surgery with follow-up 6 and 12 months after surgery. RESULTS: Five hundred and twenty-one patients were alive after 12 months, 462 (89%) and 465 (89.4%) responded after 6 and 12 months, respectively. Female patients had less favorable scores than male patients on most subscales of the SF-36 both before and after surgery. Both male and female patients improved substantially after surgery, but female patients reported significantly less improvement on two of eight subscales of the SF-36; role emotional and bodily pain. CONCLUSION: The study demonstrates that there are sex differences concerning HRQOL both before and after cardiac surgery. A clear overall improvement in HRQOL over the first year after cardiac surgery, more specifically during the first 6 months for both sexes was found.  相似文献   
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