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During the wet season of 2010, yellow fever virus (YFV) was detected in field-collected mosquitoes in the Kédougou region in southeastern Senegal. During this outbreak, we studied the association of the abundance of YFV-infected mosquitoes and land cover features to try and understand the dynamics of YFV transmission within the region. In total, 41,234 mosquito females were collected and tested for virus infection in 5,152 pools. YFV was detected in 67 pools; species including Aedes furcifer (52.2% of the infected pools), Ae. luteocephalus (31.3% of the infected pools), Ae. taylori (6.0% of the infected pools) and six other species (10.4% of the infected pools) captured in September (13.4%), October (70.1%), and November (16.4%). Spatially, YFV was detected from mosquitoes collected in all land cover classes but mainly, forest canopies (49.2%). Human infection is likely mediated by Ae. furcifer, the only species found infected with YFV within villages. Villages containing YFV-infected mosquitoes were significantly closer to large forests (> 2 ha) than villages in which no infected mosquitoes were detected.  相似文献   
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Oral Diseases (2012) 19 , 46–58 Sjögren’s syndrome (SjS) is one of the most common autoimmune rheumatic diseases, clinically characterized by xerostomia and keratoconjunctivitis sicca. We investigated the following controversial topics: (i) Do we have reliable ways of assessing saliva production? (ii) How important are the quantity and quality of saliva? (iii) Are only anti‐SSA/Ro and anti‐SSB/La relevant for the diagnosis of SjS? (iv) Are the American‐European Consensus criteria (AECC) the best way to diagnose SjS? Results from literature searches suggested the following: (i) Despite the fact that numerous tests are available to assess salivation rates, direct comparisons among them are scarce with little evidence to suggest one best test. (ii) Recent developments highlight the importance of investigating the composition of saliva. However, more research is needed to standardize the methods of analysis and collection and refine the quality of the accumulating data. (iii) In addition to anti‐Ro/La autoantibodies, anti α‐fodrin IgA and anti‐MR3 autoantibodies seem to be promising diagnostic markers of SjS, but more studies are warranted to test their sensitivity and specificity. (iv) AECC are classification, not diagnostic criteria. Moreover, recent innovations have not been incorporated into these criteria. Consequently, treatment directed to patients diagnosed using the AECC might exclude a significant proportion of patients with SjS.  相似文献   
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Several animal studies indicate that mercury is a male reproductive toxicant, but human studies are few and contradictory. We examined semen characteristics and serum levels of reproductive hormones in relation to environmental exposure to mercury. Blood and semen samples were collected from 529 male partners of pregnant women living in Greenland, Poland and Ukraine between May 2002 and February 2004. The median concentration of the total content of mercury in whole blood was 9.2 ng ml−1 in Greenland (0.2–385.8 ng ml−1), 1.0 ng ml−1 in Poland (0.2–6.4 ng ml−1) and 1.0 ng ml−1 in Ukraine (0.2–4.9 ng ml−1). We found a significantly positive association between the blood levels of mercury and serum concentration of inhibin B in men from Greenland (β=0.074, 95% confidence interval (CI)=0.021 to 0.126) and in an analysis including men from all three regions (β=0.067, 95% CI=0.024 to 0.110). The association may be due to beneficial effects of polyunsaturated fatty acids (PUFAs), which are contained in seafood and fish. No significant association (P>0.05) was found between blood concentrations of mercury and any of the other measured semen characteristics (semen volume, total sperm count, sperm concentration, morphology and motility) and reproductive hormones (free androgen index (FAI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone and LH×testosterone) in any region. In conclusion, the findings do not provide evidence that environmental mercury exposure in Greenlandic and European men with median whole blood concentration up to 10 ng ml−1 has adverse effects on biomarkers of male reproductive health.  相似文献   
36.
Infective endocarditis represents a classical contra-indication to thrombolysis for acute ischemic stroke due to a potential increased risk of intracranial hemorrhage. However, some case reports have suggested safety and potential efficacy of intravenous or intra-arterial thrombolysis in stroke related to infective endocarditis. We present a case of ischemic stroke related to infective endocarditis who was treated with intravenous tissue plasminogen activator within the first 3 h of symptoms onset and subsequently developed symptomatic multifocal intracerebral hemorrhages, and summarize currently available data on this issue.  相似文献   
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Malaria immunology, molecular biology and pathogenicity studies often require the adaptation of Plasmodium falciparum field isolates to continuous in vitro cultivation. For this purpose we have established propagation protocols of asexual erythrocytic stages of P. falciparum samples from malaria patients or asymptomatic carriers in Mali. The parasites were grown in standard culture medium supplemented by human serum and in a culture medium without human serum but supplemented by AlbuMax 1. The candle jar environment and tissue culture flasks gassed with 5% CO2, 5% O2 and 90% N2 obtained from a portable gas mixer were used. Protocols for parasite cultivation in a resource-poor setting were developed. These protocols were successfully applied to fresh isolates in Mali as well as to blood samples frozen in liquid nitrogen and shipped to a laboratory in U.S.A.  相似文献   
39.
Bloodstream infections (BSIs) are common, however international guidelines are available only for methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia and candidaemia. This international ESCMID cross-sectional survey, open from December 2016 to February 2017, explored the management of BSIs by infection specialists. All infection specialists (senior or trainees) giving at least weekly advice on positive blood cultures could participate. Their practices were evaluated using six clinical vignettes presenting uncomplicated BSI cases. A total of 616 professionals from 56 countries participated [333/616 (54%) infectious diseases specialists, 188/616 (31%) clinical microbiologists], of whom 76% (468/616) were members of an antimicrobial stewardship team. Large variations in practice were noted, in particular for the Escherichia coli, Enterococcus faecalis and Pseudomonas aeruginosa vignettes. Echocardiography was considered standard of care by 81% (373/459) of participants for MRSA, 78% (400/510) for methicillin-susceptible S. aureus and 60% (236/395) for Candida albicans. Antimicrobial combination therapy was recommended by 2% (8/360) of respondents for C. albicans, 11% (43/378) for E. coli, 27% (114/420) for MRSA and 39% (155/393) for E. faecalis. Intravenous-to-oral switch was considered in 68% (285/418) for MRSA, 79% (306/388) for E. faecalis, 72% (264/366) for P. aeruginosa and 75% (270/362) for C. albicans. In multivariable analysis, IDSA guideline-compliant practice was more frequent among participants belonging to an antimicrobial stewardship team (aOR?=?1.7, P?=?0.018 for the MRSA vignette; and aOR?=?2.0, P?=?0.008 for the candidaemia vignette). This survey showed large variations in practice among infection specialists. International guidelines on management of BSI are urgently needed.  相似文献   
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