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971.
Auvert B Marseille E Korenromp EL Lloyd-Smith J Sitta R Taljaard D Pretorius C Williams B Kahn JG 《PloS one》2008,3(8):e2679
Background
Trials in Africa indicate that medical adult male circumcision (MAMC) reduces the risk of HIV by 60%. MAMC may avert 2 to 8 million HIV infections over 20 years in sub-Saharan Africa and cost less than treating those who would have been infected. This paper estimates the financial and human resources required to roll out MAMC and the net savings due to reduced infections.Methods
We developed a model which included costing, demography and HIV epidemiology. We used it to investigate 14 countries in sub-Saharan Africa where the prevalence of male circumcision was lower than 80% and HIV prevalence among adults was higher than 5%, in addition to Uganda and the Nyanza province in Kenya. We assumed that the roll-out would take 5 years and lead to an MC prevalence among adult males of 85%. We also assumed that surgery would be done as it was in the trials. We calculated public program cost, number of full-time circumcisers and net costs or savings when adjusting for averted HIV treatments. Costs were in USD, discounted to 2007. 95% percentile intervals (95% PI) were estimated by Monte Carlo simulations.Results
In the first 5 years the number of circumcisers needed was 2 282 (95% PI: 2 018 to 2 959), or 0.24 (95% PI: 0.21 to 0.31) per 10 000 adults. In years 6–10, the number of circumcisers needed fell to 513 (95% PI: 452 to 664). The estimated 5-year cost of rolling out MAMC in the public sector was $919 million (95% PI: 726 to 1 245). The cumulative net cost over the first 10 years was $672 million (95% PI: 437 to 1 021) and over 20 years there were net savings of $2.3 billion (95% PI: 1.4 to 3.4).Conclusion
A rapid roll-out of MAMC in sub-Saharan Africa requires substantial funding and a high number of circumcisers for the first five years. These investments are justified by MAMC''s substantial health benefits and the savings accrued by averting future HIV infections. Lower ongoing costs and continued care savings suggest long-term sustainability. 相似文献972.
Elham Rahme Kaberi Dasgupta Mark Burman Hongjun Yin Sasha Bernatsky Greg Berry Hacene Nedjar Susan R. Kahn 《CMAJ》2008,178(12):1545-1554
Background
Patients undergoing hip or knee replacement are at high risk of developing a postoperative venous thromboembolism even after discharge from hospital. We sought to identify hospital and patient characteristics associated with receiving thromboprophylaxis after discharge and to compare the risk of short-term mortality among those who did or did not receive thromboprophylaxis.Methods
We conducted a retrospective cohort study using system-wide hospital discharge summary records, physician billing information, medication reimbursement claims and demographic records. We included patients aged 65 years and older who received a hip or knee replace ment and who were discharged home after surgery.Results
In total we included 10 744 patients. Of these, 7058 patients who received a hip replacement and 3686 who received a knee replacement. The mean age was 75.4 (standard deviation [SD] 6.8) years and 38% of patients were men. In total, 2059 (19%) patients received thomboprophylaxis at discharge. Patients discharged from university teaching hospitals were less likely than those discharged from community hospitals to received thromboprophylaxis after discharge (odds ratio [OR] 0.89, 95% confidence interval [CI] 0.80–1.00). Patients were less likely to receive thromboprophylaxis after discharge if they had a longer hospital stay (15–30 days v. 1–7 days, OR 0.69, 95% CI 0.59–0.81). Patients were more likely to receive thromboprophylaxis if they had hip (v. knee) replacement, osteoarthritis, heart failure, atrial fibrillation or hypertension, higher (v. lower) income or if they were treated at medium-volume hospitals (69–116 hip and knee replacements per year). In total, 223 patients (2%) died in the 3-month period after discharge. The risk of short-term mortality was lower among those who received thromboprophylaxis after discharge (hazard ratio [HR] 0.34, 95% CI 0.20–0.57).Interpretation
Fewer than 1 in 5 elderly patients discharged home after a hip-or knee-replacement surgery received postdischarge thromboprophylaxis. Those prescribed these medications had a lower risk of short-term mortality. The benefits of and barriers to thromboprophylaxis therapy after discharge in this population requires further study.Venous thromboembolism is a leading cause of mortality among patients in hospital.1,2 Major orthopedic surgery (e.g., hip or knee replacement) is associated with a high risk for postoperative venous thromboembolism.1,3,4 Because the clinical diagnosis of venous thromboembolism is unreliable and its first manifestation may be a life-threatening pulmonary embolism,5 it is recommended that patients undergoing hip or knee replacement receive routine thromboprophylaxis with anticoagulant therapy after surgery unless they have contraindications to anticoagulant therapy.1,3,5,6Thromboprophylaxis is commonly administered for the entire hospital stay, which is usually between 4 and 14 days.7 Expert consensus guidelines recommend that patients undergoing hip or knee replacement receive thromboprophylaxis medications for at least 10 days after surgery.6 These guidelines also recommend extended thromboprophylaxis for up to 28–35 days after surgery for patients undergoing hip replacement.6 Although there is evidence that extended thromboprophylaxis after hospital discharge is effective for reducing the risk of venous thromboembolism among patients who undergo hip replacement,8 the benefit among patients who undergo knee replacement has not been established.6 Thromboprophylaxis after discharge is likely to most benefit patients at high risk for venous thromboembolism, such as those with cancer, heart failure or major respiratory disease.6–9 However, given that patients who undergo joint replacement are often elderly and have multiple comorbidities, the risks associated with extended thromboprophylaxis, particularly gastrointestinal bleeding and hemorrhagic strokes, may be substantial and may be relative contraindications for this therapy.10Among patients discharged home after hip-or knee-replacement surgery, we sought characterize the use of thromboprophylaxis after discharge and its consequences on risk of short-term mortality. 相似文献973.
Women in the child-bearing age of 15 to 44 years and, in particular, pregnant and lactating women in this age cohort are considered a sensitive subpopulation when assessing risk from ingestion of water because water borne contaminants may pose a risk not only to the mother but to the fetus or infant. This article presents estimates of daily average per capita water ingestion for women of child-bearing age and in three subgroups: pregnant, lactating, and non-pregnant/non-lactating women. Estimates of means and upper percentiles of subgroup ingestion distributions were generated using participant responses and survey weights from the United States Department of Agriculture's (USDA) 1994–96 and 1998 Continuing Survey of Food Intake by Individuals (CSFII). The ingestion estimates are empirical and not based on an assumed parametric distribution of daily average amount of water ingestion. Water occurring naturally in foods or added by manufacturers to commercial products is not included in the estimates presented. These estimates of water ingestion by women of child-bearing age are compared to those attributed to Ershow and Cantor (1989) by Burmaster (1998). These estimates, based on data collected in 1978, were used by Burmaster to characterize the distribution of daily average per capita ingestion as lognormal. The lognormal estimates of total water ingestion are generally greater than the total water ingestion estimates based on the CSFII data. Possible explanations for the differences are discussed. 相似文献
974.
Rajala A Tanito M Le YZ Kahn CR Rajala RV 《The Journal of biological chemistry》2008,283(28):19781-19792
Insulin receptor (IR) signaling provides a trophic signal for transformed retinal neurons in culture, but the role of IR activity in vivo is unknown. We previously reported that light causes increased tyrosine phosphorylation of the IR in vivo, which leads to the downstream activation of the phosphoinositide 3-kinase and Akt pathway in rod photoreceptor cells. The functional role of IR in rod photoreceptor cells is not known. We observed that light stress induced tyrosine phosphorylation of the IR in rod photoreceptor cells, and we hypothesized that IR activation is neuroprotective. To determine whether IR has a neuroprotective role on rod photoreceptor cells, we used the Cre/lox system to specifically inactivate the IR gene in rod photoreceptors. Rod-specific IR knock-out mice have reduced the phosphoinositide 3-kinase and Akt survival signal in rod photoreceptors. The resultant mice exhibited no detectable phenotype when they were raised in dim cyclic light. However, reduced IR expression in rod photoreceptors significantly decreased retinal function and caused the loss of photoreceptors in mice exposed to bright light stress. These results indicate that reduced expression of IR in rod photoreceptor cells increases their susceptibility to light-induced photoreceptor degeneration. These data suggest that the IR pathway is important for photoreceptor survival and that activation of the IR may be an essential element of photoreceptor neuroprotection. 相似文献
975.
Phospholipid transfer protein (PLTP) activity is elevated in obese and diabetic subjects. No prospective studies have examined the effect of weight loss on PLTP activity and assessed whether the resultant changes in activity are related to changes in body weight, insulin resistance, or both. PLTP activity was measured at baseline in 46 subjects (body mass index = 19-64 kg/m2) and after diet-induced weight loss in 19 of the obese subjects. Total body fat mass (FM) by dual-energy X-ray absorptiometry, intraabdominal fat (IAF), and abdominal subcutaneous fat (SQF) by CT scan, insulin sensitivity (SI) by frequently sampled intravenous glucose tolerance test, leptin, and lipids were determined. At baseline, PLTP activity correlated with FM (r = 0.36, P = 0.02) and SQF (r = 0.31, P = 0.045), but not with IAF (r = 0.16, P = 0.32) or SI (r = 0.10, P = 0.52). With diet-induced weight loss (16 +/- 7.3 kg), PLTP activity significantly decreased 9.1% (P = 0.002). The change in PLTP activity correlated with the change in SQF (r = 0.55, P = 0.014) (33.6% decrease), but not with IAF (r = 0.09, P = 0.73) or SI (r = 0.18, P = 0.44), and was highly correlated with the change in nonesterified fatty acid (NEFA) (r = 0.71, P < 0.001). In conclusion, elevated PLTP activity in obese subjects is likely a result of increased body fat, reflected by SQF, and is influenced by NEFAs but is not directly related to insulin resistance. 相似文献
976.
977.
The kinetics of photoconversion of protochlorophyll(ide) to chlorophyll(ide) a were investigated in dark-grown barley leaves and in a preparation of protochlorophyll holochrome subunits. In the subunits the conversion obeyed first-order kinetics. This indicates that the excitation of protochlorophyll(ide), energy loss through deexcitation, and the reduction of excited protochlorophyll(ide) are all reactions that follow first-order kinetics with respect to protochlorophyll(ide) in protochlorophyll holochrome subunits.In contrast, photoconversion in leaves obeyed neither first- nor second-order kinetics. This prompted the postulation of an additional route within macromolecular units of protochlorophyll holochrome, whereby energy is lost from excited protochlorophyll(ide) by a reaction that is not first order. Such a process might be energy transfer from excited protochlorophyll(ide) to newly-formed chlorophyll(ide) a.A dynamic model describing photoconversion in macromolecular units was derived. The model is consistent with the observed progress of photoconversion in barley leaves and in protochlorophyll holochrome subunits from barley.Determinations of the quantum yield of photoconversion in protochlorophyll holochrome subunits gave values of 0.4–0.5 molecules · quantum?1. Estimates of the initial quantum yield of the photoconversion process in leaves fell into the same range. The dynamic model allows predictions on the progressively decreasing quantum yield as the photoconversion proceeds in macromolecular units. 相似文献
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980.