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91.
HIV-1 infection is associated with serious cardiovascular complications, but the roles of HIV-1, viral proteins, and highly active antiretroviral therapy (HAART) drugs are not understood. HAART decreases the overall risk of heart disease but leads to metabolic disturbances and possibly coronary artery disease. We investigated toxicities of HIV-1, HIV-1 glycoprotein 120 (gp120), and HAART drugs for human coronary artery endothelial cells (CAECs), brain microvascular endothelial cells, and neonatal rat ventricular myocytes (NRVMs). HIV-1 and gp120, but not azidothymidine (AZT), induced apoptosis of NRVMs and CAECs. Ethylisothiourea, an inhibitor of nitric oxide synthase, inhibited apoptosis induction by gp120. AZT, HIV-1, and gp120 all damaged mitochondria of cardiomyocytes. HAART drugs, AZT, and indinavir, but not HIV-1, produced intercellular gaps between confluent endothelial cells and decreased transendothelial electrical resistance. In conclusion, HIV-1 and gp120 induce toxicity through induction of cardiomyocyte and endothelial cell apoptosis. HAART drugs disrupt endothelial cell junctions and mitochondria and could cause vascular damage.  相似文献   
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Factors Influencing the Rate of Fibrosis Progression in Chronic Hepatitis C   总被引:3,自引:0,他引:3  
Alcohol consumption, age at infection, and male gender have been identified as risk factors for faster fibrosis progression in patients with chronic hepatitis C (CHC). Yet the influence of liver steatosis, light to moderate alcohol consumption, or iron overload on this progression remains controversial. To analyze the effect of individual risk factors and their interaction on fibrosis progression in a group of patients with CHC and a definite date of infection, we studied 133 consecutive untreated patients. Covariates included were age, body mass index (BMI), gender, age at infection, alcohol intake, serum lipids, glycemia, serum ALT, AST, GGT, iron, and ferritin, grade and stage (METAVIR and Scheuer), and hepatic stainable iron (Perl's stain). The rate of fibrosis progression was inferred from the METAVIR score. By logistic regression analysis, hepatic steatosis (odds ratio [OR], 3.035; 95% confidence interval [CI], 1.16-7.93), serum ferritin levels higher than 290 ng/ml (OR, 5.5; 1.6-18.65), and light to moderate ethanol intake (1-50 g/day) (OR, 5.22; 1.5-17.67) were independently associated with faster fibrosis progression. There was no effect of interaction between these variables on the rate of fibrosis progression. Liver steatosis, serum ferritin levels, and light to moderate alcohol intake are associated with faster fibrosis progression in chronic hepatitis C. Combination of these factors did not further accelerate this progression. The impact of modification of these factors on progression should be tested in longitudinal studies.  相似文献   
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Congenital hypofibrinogenemia is a rare bleeding disorder characterized by abnormally low levels of fibrinogen in plasma, generally due to heterozygous mutations in one of the three fibrinogen genes (FGA, FGB, and FGG, coding for Aα, Bβ, and γ chain, respectively). Hypofibrinogenemic patients are usually asymptomatic, whereas individuals bearing similar mutations in the homozygous or compound heterozygous state develop a severe bleeding disorder: afibrinogenemia. The mutational spectrum of these quantitative fibrinogen disorders includes large deletions, point mutations causing premature termination codons, and missense mutations affecting fibrinogen assembly or secretion, distributed throughout the 50-kb fibrinogen gene cluster. In this study, we report the mutational screening of two unrelated hypofibrinogenemic patients leading to the identification of two missense mutations, one hitherto unknown (αCys45Phe), and one previously described (γAsn345Ser). The involvement of αCys45Phe and γAsn345Ser in the pathogenesis of hypofibrinogenemia was investigated by in-vitro expression experiments. Both mutations were demonstrated to cause a severe impairment of intracellular fibrinogen processing, either by affecting half-molecule dimerization (αCys45Phe) or by hampering hexamer secretion (γAsn345Ser).  相似文献   
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The proportion of pretreatment bone marrow macrolymphoblasts was determined in a total of 93 children with acute lymphoblastic leukaemia (ALL) in order to assess the validity of cell size as a prognostic indicator. A macrolymphoblast (MLb) was defined as having a diameter greater than 12 μm, and patient samples were divided simply on the basis of whether they had more or less than 10% MLb present at diagnosis. In a retrospective study of a sample of 47 children treated according to Total Therapy Study VII, the continuous complete remission duration, survival and incidence of CNS disease bore no relationship to the cell size distribution present at diagnosis. A second sample of 46 current patients with untreated ALL was examined both for the presence of surface markers for T- and B-cells and for cell size. Bone marrow blasts from 10 of these 46 children formed rosettes with sheep erythrocytes (E)—a T-cell marker. E-rosette formation was associated with a constellation of adverse prognostic factors, including older age, very high initial WBC counts, organomegaly, and mediastinal enlargement; yet the presence of this T-cell marker was unrelated to cell size. We conclude that pretreatment lymphoblast cell size is not a reliable prognostic indicator in childhood ALL.  相似文献   
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The liver contribution to the biological network underlying physical frailty in aging is underestimated. How best to measure this contribution magnitude and impact on health risk trajectories in frail individuals is not yet entirely clear. We analyzed the association of a novel liver frailty phenotype with the risk of death in older participants of the Salus in Apulia Study cohort. Clinical and physical examination, routine biomarkers, medical history, and anthropometry were analyzed in 1929 older adults (65?+). Physical frailty was classified by Cardiovascular Health Study criteria, and liver fibrosis risk by fibrosis-4 (FIB-4). The liver frailty phenotype was defined as physical frailty plus high-risk liver fibrosis (score?>?2.67). Physical frailty, high-risk liver fibrosis, and liver frailty subjects were compared to subjects without these conditions (non-frail). Proportional Cox regression tested the adjusted association between liver frailty and all-cause mortality for each category. The liver frailty prevalence was relatively low (3.8%), but higher in men (58.1%). Compared to non-frail older subjects, liver frailty subjects were significantly older (effect size (ES)???1.11, 95% confidence interval (CI)???1.35 to???0.87), with a lower education (ES 0.48, 95%CI 0.24 to 0.71) and higher multimorbidity (ES 15.81, 95%CI 4.20 to 27.41). Cox multivariate analyses showed a two-fold increased risk of overall mortality (hazard ratio 2.09, 95%CI 1.16–3.74) even after the adjustment for age, sex, education, and alcohol consumption. The liver frailty phenotype runs twice the risk of overall mortality compared with the non-frail population. This clinical tool, validated in a Southern Italian population, is based on simple sets of measures that can conveniently be assessed also in the primary care setting.

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