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671.
OBJECTIVES: To utilize cytokine levels to predict sustained response (SR) to alpha interferon (IFN alpha) therapy in chronic hepatitis C patients, and to determine the relationship between serum tumor necrosis factor alpha (TNF alpha), interleukin (IL) IL 6, IL 8, IL 12, transforming growth factor beta (TGF beta 1) and the degree of liver damage as reflected by traditional markers. DESIGN AND METHODS: Serum cytokine levels were assessed using ELISA in 18 patients included in a controlled clinical trial of IFN alpha. RESULTS: Of the 18 patients, 27% were sustained responders (SR), 27% were response and relapse responders (RR), and 46% were non-responders (NR). Multivariate analysis showed that a low serum TNF alpha level and high serum IL 8 levels were independent factors associated with SR to IFN alpha therapy. Serum TNF alpha level highly correlated with viral load and genotype predictive values (p < 0.001). Therapy lowered the IL 6 and IL 12 profile. TGF beta 1 levels in serum are positively correlated with fibrinogenesis. CONCLUSIONS: IFN alpha therapy modulates immune response to hepatitis C virus, contributing to sustained response.  相似文献   
672.
Evidence is emerging from rigorous evaluations about the effectiveness of nutrition‐sensitive agriculture programmes in improving nutritional outcomes. Additional evidence can elucidate how different programme components and pathways contribute and can be optimized for impact. The International Food Policy Research Institute, with Helen Keller International, designed a comprehensive framework to evaluate the delivery, utilization, and impact of Helen Keller International's enhanced homestead food production programme in Burkina Faso. After 18 months of implementation, a process evaluation was conducted to examine programme impact pathways, using key informant and semistructured interviews with implementing agents and beneficiaries, and with residents of control communities. Data were analyzed by International Food Policy Research Institute and reviewed with project managers and partners through multiple workshops to identify opportunities to strengthen implementation. Findings illuminated gaps between intended and actual delivery schemes, including input constraints, knowledge gaps among community agents in agriculture and young child nutrition practices, and lower than expected activity by community volunteers. In response, staff developed measures to overcome water constraints and expand vegetable and poultry production, retrained volunteers in certain techniques of food production and counselling for nutrition behaviour change, added small incentives to motivate volunteers, and shaped both immediate and long‐term changes to the programme model. Working closely with International Food Policy Research Institute on the evaluation activities also expanded the repertoire of research methods and skills of Helen Keller International staff. Process evaluation can strengthen programme delivery, utilization, and design. Collaboration between researchers and implementers can improve programme effectiveness, project staff capacity, and advance delivery science.  相似文献   
673.
There is longstanding evidence that immunoglobulin G (IgG) has a role in protection against clinical malaria, and human antibodies of the cytophilic subclasses are thought to be particularly critical in this respect. In this cohort study, 286 Burkinabè children 6 months to 15 years old were kept under malaria surveillance in order to assess the protective role of antibody responses against four antigens which are currently being evaluated as vaccine candidates: apical membrane antigen 1 (AMA1), merozoite surface protein 1-19 (MSP1-19), MSP3, and glutamate-rich protein (GLURP). Total IgG, IgM, and IgG subclass responses were measured just before the malaria transmission season. The incidence of malaria was 2.4 episodes per child year of risk. After adjusting for the confounding effects of age, the level of total IgG to GLURP was strongly associated with reduced malaria incidence (incidence rate ratio associated with a doubling of total IgG, 0.79; 95% confidence interval, 0.66 to 0.94; P = 0.009.); there was a borderline statistically significant association between the level of total IgG to MSP3 and malaria incidence and no evidence of an association for total IgG to AMA1 and to MSP1-19. Of the IgG subclass responses studied, only IgG3 and IgG4 against GLURP and IgG1 against AMA1 were associated with reduced risk of clinical malaria. There was no evidence of an interaction between responses to AMA1 and baseline parasitemia in their effects on malaria incidence. Currently included in malaria vaccine formulations for clinical trials in humans, these blood-stage antigens, AMA1 and GLURP, offer good prospects for malaria vaccine development.  相似文献   
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675.
Clinical Rheumatology - The aim of this work is to study the epidemiological characteristics of rheumatic conditions in a cohort of 23,550 patients followed up in Ouagadougou, Burkina Faso. This...  相似文献   
676.
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