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When Shiga toxin-producing Escherichia coli (STEC) strains emerged as agents of human disease, two types of toxin were identified: Shiga toxin type 1 (Stx1) (almost identical to Shiga toxin produced by Shigella dysenteriae type 1) and the immunologically distinct type 2 (Stx2). Subsequently, numerous STEC strains have been characterized that express toxins with variations in amino acid sequence, some of which confer unique biological properties. These variants were grouped within the Stx1 or Stx2 type and often assigned names to indicate that they were not identical in sequence or phenotype to the main Stx1 or Stx2 type. A lack of specificity or consistency in toxin nomenclature has led to much confusion in the characterization of STEC strains. Because serious outcomes of infection have been attributed to certain Stx subtypes and less so with others, we sought to better define the toxin subtypes within the main Stx1 and Stx2 types. We compared the levels of relatedness of 285 valid sequence variants of Stx1 and Stx2 and identified common sequences characteristic of each of three Stx/Stx1 and seven Stx2 subtypes. A novel, simple PCR subtyping method was developed, independently tested on a battery of 48 prototypic STEC strains, and improved at six clinical and research centers to test the reproducibility, sensitivity, and specificity of the PCR. Using a consistent schema for nomenclature of the Stx toxins and stx genes by phylogenetic sequence-based relatedness of the holotoxin proteins, we developed a typing approach that should obviate the need to bioassay each newly described toxin and that predicts important biological characteristics.  相似文献   
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Major clinical studies have shown that the targets for blood glucose, lipid profile and blood pressure in type 2 diabetic patients are difficult to maintain in clinical practice. However, there are few data concerning South American populations. Using guidelines represented by the Brazilian Diabetes Society, we evaluated cardiovascular (CV) risk factors, glycemic control and the availability of screening for diabetes complications in 2233 (60% females) outpatients with type 2 diabetes aged 59.2 +/- 11.3 yr and with a known duration of diabetes of 9.2 +/- 7.2 yr, collected from 8 Brazilian cities. The outcome showed that less intensive clinical care available for diabetic patients in Brazil compared to western industrialized countries leads to widespread poor metabolic control and health status. Less than 30% of the patients reached the target for systolic (28.5%, < 130 mmHg) and diastolic (19.3%, < 80 mmHg) blood pressure, BMI (24.6%, < 25 kg/m2), LDL cholesterol (20.6%, < 2.6 mmol/l) and only 46% reached the goal for HbA1c (one % point above the upper limits of normality for the method used). Only 0.2% of patients reached all the targets. A lower number of women reached the targets for HbA1c, LDL and HDL cholesterol than men (p < 0.001). Women were less likely than men to have funduscopy examinations and urine albumin testing (p < 0.001). We conclude that the national goals for glycemic control, blood pressure and lipid levels are rarely achieved in clinical practice, and that the availability for diabetic complication screening is low. The quality of diabetes care, in particular for women, is poor and should be further reviewed in developing countries.  相似文献   
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PURPOSE: The effectiveness of massage therapy on immune parameters was evaluated in young Dominican HIV+ children without current access to antiretroviral therapies. METHODS: Eligible children, who were followed at the Robert Reid Cabral Hospital (San Domingo, Dominican Republic), were randomized to receive either massage treatment or a control/friendly visit twice weekly for 12 weeks. Blood was drawn at baseline and following the 3-month intervention for determinations of CD4, CD8, and CD56 cell counts and percentage, along with activation markers (CD25 and CD69). RESULTS: Despite similar immune parameters at baseline in the two groups, significantly more of the control group exhibited a decline in CD4 cell count (>30%, p = 0.03), postintervention. The decrease was particularly evident in older (5-8 years) children in the control arm, who demonstrated a significant reduction in both CD4 and CD8 cell counts compared to massage-treated older children who remained stable or showed immune improvement. Additionally, a significant increase in CD4+CD25+ cells was observed over the 12-week trial in the massage-treated older children (p = 0.04) but not in the control group. In younger massage-treated children, (2-4 years old), a significant increase in natural killer cells was shown. CONCLUSION: Together these findings support the role for massage therapy in immune preservation in HIV+ children.  相似文献   
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Influenza epidemics are responsible for high mortality and morbidity rates in particular among elderly and high risk groups. This review is aimed at assessing the economic value of vaccination in these groups. A search of full economic evaluations of influenza vaccination in comparison with no interventions was performed on PubMed from January 1990 to May 2011. Only economic evaluations dealing with elderly and high risk groups were considered. The quality of selected articles was assessed through Drummond's checklist. Sixteen cost-effectiveness analyses and four cost-benefit analyses were included: overall, the quality of studies was fairly good. The vaccination was demonstrated to be cost-effective or cost-saving in almost all studies, independently by the perspective and the type of analysis. Influenza vaccination is a worthwhile intervention from the pharmacoeconomic view-point, anyway a standardization of methods should be desirable in order to guarantee the comparability and transferability of results.  相似文献   
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This study mapped the application of financing in research and development in health (R&D/H) by the Brazilian Ministry of Health in 2003-2005, according to the National Agenda for Health Research Priorities, created in 2004. The analysis was based on data from a study aimed primarily at measuring these investment flows during the same period. The calculations included only direct financing with actual outlays in research, including payroll expenditures. The studies were categorized according to the 24 sub-agendas of the national priority agenda by two independent researchers, and disagreements were resolved by consensus. Research and development expenditures in health totaled 409.7 million reais, concentrated mainly in the following sub-agendas: transmissible diseases, the health industry complex, clinical research, pharmaceutical care, and non-communicable diseases (79% of the total). All 24 sub-agendas received some financing during the period. The study established a baseline for subsequent evaluations of this financing instrument's inductive capacity and the relationship between R&D/H investments and the population's health needs.  相似文献   
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