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21.
Heart Failure Reviews - Neuromuscular diseases (NMDs) include a broad spectrum of disorders that affect motor unit in every possible site, extending from the cell body of peripheral nerves to the...  相似文献   
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We studied the course of virologic breakthroughs detected by a quantitative polymerase chain reaction (PCR) assay in 32 of 78 patients with hepatitis B e antigen (HBeAg)-negative precore mutant hepatitis B virus (HBV) chronic liver disease under long-term lamivudine monotherapy. Serum HBV DNA levels were measured every 3 months and on every biochemical breakthrough. YMDD mutants were detected in 30 of the 32 patients with virologic breakthroughs. Among these 32 patients, biochemical remission rate was 44% at 6 months, 21% at 12 months, and 0% at 24 months after the onset of virologic breakthrough. Development of biochemical breakthroughs was associated with a significant increase of serum HBV DNA levels, which exceeded 100,000 copies/mL in 19 of 20 patients (95%) with biochemical breakthroughs and in only 1 of 8 patients (12.5%) remaining in biochemical remission for at least 6 months after the onset of virologic breakthrough (P <.001). Alanine aminotransferase (ALT) level peaked within 0 to 3 months after the onset of biochemical breakthrough and decreased at 6 months but remained abnormal in all but 2 patients. Follow-up liver histologic lesions in patients with biochemical breakthroughs did not differ from baseline findings, although they were significantly improved in patients remaining in virologic and biochemical remission. In conclusion, the frequent emergence of viral resistance under long-term lamivudine monotherapy in HBeAg-negative precore mutant HBV chronic liver disease is followed by increasing viremia levels culminating in the development of biochemical breakthroughs in most cases. ALT activity peaks close to the onset of biochemical breakthrough, decreasing thereafter but remaining persistently abnormal with fluctuating levels.  相似文献   
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Indoleamine 2,3-dioxygenase (IDO) suppresses adaptive immunity. T-cell proliferation and differentiation to effector cells require increased glucose consumption, aerobic glycolysis and glutaminolysis. The effect of IDO on the above metabolic pathways was evaluated in alloreactive T-cells. Mixed lymphocyte reaction (MLR) in the presence or not of the IDO inhibitor, 1-methyl-dl-tryptophan (1-MT), was used. In MLRs, 1-MT decreased tryptophan consumption, increased cell proliferation, glucose influx and lactate production, whereas it decreased tricarboxylic acid cycle activity. In T-cells, from the two pathways that could sense tryptophan depletion, i.e. general control nonrepressed 2 (GCN2) kinase and mammalian target of rapamycin complex 1, 1-MT reduced only the activity of the GCN2 kinase. Additionally 1-MT treatment of MLRs altered the expression and/or the phosphorylation state of glucose transporter-1 and of key enzymes involved in glucose metabolism and glutaminolysis in alloreactive T-cells in a way that favors glucose influx, aerobic glycolysis and glutaminolysis. Thus in alloreactive T-cells, IDO through activation of the GCN2 kinase, decreases glucose influx and alters key enzymes involved in metabolism, decreasing aerobic glycolysis and glutaminolysis. Acting in such a way, IDO could be considered as a constraining factor for alloreactive T-cell proliferation and differentiation to effector T-cell subtypes.  相似文献   
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Background

Since scarce data exist on the pathogenesis of nasopharyngeal carcinoma in Caucasian patients, we attempted to elucidate the responsible molecular pathways in this patient population.

Methods

Formalin-fixed paraffin-embedded tumor tissue samples from 107 patients, diagnosed with locally-advanced nasopharyngeal carcinoma and treated with chemotherapy or chemo-radiotherapy, were analyzed by immunohistochemistry for the expression of the following proteins: E-cadherin, P-cadherin, Fascin-1, Cyclin D1, COX-2, EGFR, VEGF-A, VEGF-C, VEGFR-2, VEGFR-3, ERCC1, p53, p63, Ki67, MAPT, phospho-p44/42MAPK, PTEN, phospho-AKT, phospho-mTOR, and phospho-GSK-3β. EBER status was assessed by in situ hybridization. The majority of the cases were included in tissue microarray. All stains were performed and assessed centrally by two pathologists. The median follow-up time was 76.8 (42.3 – 99.2) months.

Results

Biomolecules expressed in >90% of cases were: p53, COX-2, P-cadherin, EBER, phospho-GSK-3β, and Fascin-1. WHO II+III tumors were more frequently EBER & PTEN positive and VEGF-A negative. Advanced age was significantly associated with positive phospho-GSK-3β and ERCC1 expression; male gender with positive phospho-AKT and phospho-p44/42MAPK; and worse performance status (1 or 2) with negative Ki67, ERCC1, PTEN, and phospho-mTOR expression. Earlier disease stage was closely associated with p63, MAPT, PTEN, and Cyclin D1 positivity. Univariate Cox regression analysis highlighted Cyclin D1 as a negative prognostic factor for disease-free survival (p=0.034) and EBER as a positive one for overall survival (p=0.048). In multivariate analysis, advanced age and stage, poor performance status, and positive ERCC1 emerged as predictors of worse disease-free and overall survival, as opposed to positive phospho-mTOR. Clustering analysis defined two protein-expression groups being predictive of better overall survival (p=0.043).

Conclusions

Our study is the first to examine the activation and interaction of established biomolecules and signaling pathways in Caucasian NPC patients in an effort to reveal new therapeutic targets.  相似文献   
25.
Stem cell transplantation for multiple sclerosis: what is the evidence?   总被引:7,自引:0,他引:7  
Experimental and clinical observations have indicated that high-dose immunosuppression followed by autologous stem cell transplantation (ASCT) can induce remissions in severe, refractory, autoimmune diseases including multiple sclerosis (MS), a T cell-mediated autoimmune disorder against CNS myelin components, causing severe chronic disability. Control of the disease is unsatisfactory in most of the patients, especially those with rapidly evolving relapsing-remitting course and those with chronic progressive disease. The rationale for treating autoimmune diseases with ASCT is based on the immunosuppressive and immunomodulating effects of ASCT which may shift the immunological balance towards disease quiescence, a hypothesis supported by the results of ASCT in animal models of MS and by clinical observations in MS patients transplanted for concurrent malignancies. A number of phase I-II studies of ASCT in patients with active MS, conducted worldwide since 1995, and a comprehensive analysis of 85 patients, recently reported by the European Group for Blood and Marrow Transplantation (EBMT), have shown the feasibility of the method, a prominent anti-inflammatory effect on magnetic resonance imaging (MRI) disease, and a possible clinical benefit for active and refractory cases. The impact on MRI disease parameters appears superior with ASCT than with conventional therapies but the clinical results, in terms of stabilization of disease and prevention of disability, need to be validated in prospective, controlled trials. The procedure is also associated with a transplant-related mortality risk, of about 5% in high-risk cases, i.e., in older patients, those with high disability scores, those receiving strong myeloablative conditioning regimens and those undergoing intensive in vivo or ex vivo T cell-depletion. Therefore, it could be recommended for the treatment of a chronic, non-lethal, disease like MS only if it proved superior to standard therapies. A randomized trial is now launched by the EBMT to compare ASCT to mitoxantrone, currently regarded as one of the best available treatments, in properly selected patients having high chance of response at minimal mortality risk.  相似文献   
26.
BACKGROUND: L-Arginine is a nitric oxide precursor, which augments endothelium-dependent vasodilatation in hypercholesterolemic humans and animals. Endothelium-dependent vasodilation is attenuated in patients with hypertension; however the effects of oral L-arginine on endothelial function of the conduit arteries in patients with essential hypertension have not previously been investigated. METHODS: In a prospective randomized double blind trial, 35 patients with essential hypertension received either 6 g L-arginine (18 subjects) or placebo (17 subjects). Patients were examined for flow-mediated endothelium-dependent dilatation of the brachial artery before and 1.5 h after administration of L-arginine or placebo. At the end of the protocol the nitrate-induced, endothelium-independent vasodilatation was evaluated. RESULTS: Two groups of L-arginine and placebo were similar regarding age, sex, blood lipids, smoking, diabetes, coronary artery disease, body mass index, intima-media thickness of the common carotid artery, clinics blood pressure and baseline brachial artery parameters. Administration of L-arginine or placebo did not change significantly heart rate, blood pressure, baseline diameter, blood flow or reactive hyperemia. L-Arginine resulted in a significant improvement of flow-mediated dilatation (1.7+/-3.4 vs. 5.9+/-5.4%, P=0.008) while placebo did not significantly change this parameter (3.0+/-2.7 vs. 3.1+/-2.2%, P=ns). The effect of L-arginine on flow-mediated dilatation was significantly different from the effect of placebo (P=0.05). L-Arginine did not significantly influence nitrate-induced dilatation (16+/-6.9 vs. 17.7+/-6.7%, P=ns). CONCLUSIONS: Oral administration of L-arginine acutely improves endothelium-dependent, flow-mediated dilatation of the brachial artery in patients with essential hypertension. The long-term effects of L-arginine in these patients require further investigation.  相似文献   
27.
Gastrocolic fistula is rarely described in the literature. It has been associated with a variety of diseases and recently with benign gastric ulcers related to the use of nonsteroidal anti-inflammatory drugs (NSAIDs'). The present case represents the first report of gastrocolic fistula due to NSAIDs in a cirrhotic patient. This is in keeping with the established knowledge that cirrhotic patients constitute a high-risk group of patients when treated with NSAIDs'. Review of the literature shows that this condition warrants a complete diagnostic work-up to exclude more ominous underlined diseases.  相似文献   
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