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BACKGROUND: The introduction of expensive but very effective antiviral medications has led to questions about the effects on the total use of resources for the care of patients with human immunodeficiency virus (HIV) infection. We examined expenditures for the care of HIV-infected patients since the introduction of highly active antiretroviral therapy. METHODS: We interviewed a random sample of 2864 patients who were representative of all American adults receiving care for HIV infection in early 1996, and followed them for up to 36 months. We estimated the average expenditure per patient per month on the basis of self-reported information about care received. RESULTS: The mean expenditure was $1,792 per patient per month at base line, but it declined to $1,359 for survivors in 1997, since the increases in pharmaceutical expenditures were smaller than the reductions in hospital costs. Use of highly active antiretroviral therapy was independently associated with a reduction in expenditures. After adjustments for the interview date, clinical status, and deaths, the estimated annual expenditure declined from $20,300 per patient in 1996 to $18,300 in 1998. Expenditures among subgroups of patients varied by a factor of as much as three. Pharmaceutical costs were lowest and hospital costs highest among underserved groups, including blacks, women, and patients without private insurance. CONCLUSIONS: The total cost of care for adults with HIV infection has declined since the introduction of highly active antiretroviral therapy. Expenditures have increased for medications but have declined for other services. However, there are large variations in expenditures across subgroups of patients.  相似文献   
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Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis.  相似文献   
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We examined the relationship between a functional polymorphism (667C-- >T, ala-->val) of the methylenetetrahydrofolate reductase gene (MTHFR) and the risk of colorectal adenomas in the prospective Nurses' Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval (CI) 0.84-2.17] was not significantly associated with risk of adenomas. This lack of association was observed for both small (RR = 1.36, 95% CI 0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore, there was no significant interaction between this polymorphism and consumption of either folate, methionine or alcohol. We also examined the relationship of a newly identified polymorphism (asp919gly) of the methionine synthase gene (MS) with the risk of colorectal adenomas in the same population. The MS gly/gly polymorphism was also not significantly associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70). These results, which need to be confirmed in other studies, suggest that the MTHFR val/val polymorphism, which has been previously inversely associated with risk of colorectal cancer, plays a role only in a late stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may protect against malignant transformation in the subset of benign adenomas, which may progress to malignancy.   相似文献   
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Telomere length homeostasis is essential for the long-term survival of stem cells, and its set point determines the proliferative capacity of differentiated cell lineages by restricting the reservoir of telomeric repeats. Knockdown and overexpression studies in human tumor cells showed that the shelterin subunit TPP1 recruits telomerase to telomeres through a region termed the TEL patch. However, these studies do not resolve whether the TPP1 TEL patch is the only mechanism for telomerase recruitment and whether telomerase regulation studied in tumor cells is representative of nontransformed cells such as stem cells. Using genome engineering of human embryonic stem cells, which have physiological telomere length homeostasis, we establish that the TPP1 TEL patch is genetically essential for telomere elongation and thus long-term cell viability. Furthermore, genetic bypass, protein fusion, and intragenic complementation assays define two distinct additional mechanisms of TPP1 involvement in telomerase action at telomeres. We demonstrate that TPP1 provides an essential step of telomerase activation as well as feedback regulation of telomerase by telomere length, which is necessary to determine the appropriate telomere length set point in human embryonic stem cells. These studies reveal and resolve multiple TPP1 roles in telomere elongation and stem cell telomere length homeostasis.  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) often develops in concert with related metabolic diseases, such as obesity, dyslipidemia and insulin resistance. Prolonged lipid accumulation and inflammation can progress to non-alcoholic steatohepatitis (NASH). Although factors associated with the development of NAFLD are known, triggers for the progression of NAFLD to NASH are poorly understood. Recent findings published in The Journal of Pathology reveal the possible regulation of NASH progression by metabolites of the mevalonate pathway. Mevalonate can be converted into the isoprenoids farnesyldiphosphate (FPP) and geranylgeranyl diphosphate (GGPP). GGPP synthase (GGPPS), the enzyme that converts FPP to GGPP, is dysregulated in humans and mice during NASH. Both FPP and GGPP can be conjugated to proteins through prenylation, modifying protein function and localization. Deletion or knockdown of GGPPS favors FPP prenylation (farnesylation) and augments the function of liver kinase B1, an upstream kinase of AMP-activated protein kinase (AMPK). Despite increased AMPK activation, livers in Ggpps-deficient mice on a high-fat diet poorly oxidize lipids due to mitochondrial dysfunction. Although work from Liu et al provides evidence as to the potential importance of the prenylation portion of the mevalonate pathway during NAFLD, future studies are necessary to fully grasp any therapeutic or diagnostic potential. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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OBJECTIVES: the postoperative evolution of patients submitted to orthotopic liver transplant (OLT) is frequently associated with the appearance of different types of complications such as renal failure, graft rejection, infections, and neurological disorders. These complications are the most significant causes of early morbidity and mortality in patients undergoing OLT. The purpose of the present study was the identification of factors related to the different postoperative complications after OLT. Experimental design: a prospective study was carried out. PATIENTS: seventy-eight variables were analyzed in 32 consecutive patients undergoing OLT. The factors independently associated with the appearance of postoperative complications were identified using a stepwise logistic regression analysis. RESULTS: the multivariate analysis showed that malondialdehyde and creatinine pretransplant serum levels were associated with the development of renal dysfunction. The pretransplant levels of haemoglobin and the units of platelets administered during surgery were prognostic factors of infections. Acute graft rejection was predicted by ?-glutamyl transpeptidase and total bilirubin serum levels. The pretransplant sodium and glutaredoxin levels in serum were associated with neurological complications. CONCLUSIONS: we propose these markers for the identification of high-risk patients allowing an early surveillance and/or treatment to improve morbidity and survival in patients submitted to OLT.  相似文献   
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Congestive heart failure (CHF) is the leading cause of hospitalization in the elderly, and these patients are at high risk for subsequent hospitalization. Whether gender affects the risk of rehospitalization in patients who have CHF is less well understood. We studied a random sample of 1,700 adults who had been hospitalized with CHF (from July 1, 1999 to June 30, 2000) and identified all readmissions through June 30, 2001. We used proportional hazards regression to evaluate whether gender affects the risk of all-cause and CHF-specific rehospitalization, after adjusting for differences in demographic characteristics, health-related behaviors, co-morbid conditions, left ventricular systolic function status, and use of CHF therapies. Among 1,591 adults who had confirmed CHF, 752 were women (47.3%). Women were older than men (73 vs 71 years, p <0.001) and more likely to have preserved systolic function (55.3% vs 40.9%, p <0.001), hypertension (83.1% vs 75.2%, p <0.001), and prior renal insufficiency (46.8% vs 34.6%, p <0.001). No significant differences existed between women and men with respect to crude rates of any readmission (144.7 vs 134.6 per 100 person-years, p = 0.36) or CHF-specific readmission (39.9 vs 37.4 per 100 person-years, p = 0.65). After adjusting for potential confounders, there was no significant difference between women and men with respect to risk of any readmission (adjusted hazard ratio 0.88, 95% confidence interval 0.76 to 1.02) or readmission for CHF (adjusted hazard ratio 0.89, 95% confidence interval 0.71 to 1.11). Among a contemporary, diverse population of patients who had CHF, rates of readmission overall and for CHF remained high, but gender was not independently associated with a differential risk of readmission.  相似文献   
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