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Dengue virus (DENV) causes a spectrum of illness from asymptomatic infection, to a mild febrile illness, to occasional more severe complications including hemorrhage and shock. Dengue is endemic in the state of Morelos, Mexico. Two single nucleotide polymorphisms (SNPs), rs1801274 of FcγRIIa and rs4804803 of DC-SIGN, have been associated with protection from or susceptibility to severe dengue infection. Both of these polymorphisms are located in genes for receptors with important roles in dengue pathogenesis, and their relationship with the clinical presentation of dengue infection in Mexican populations is unknown. In this study, real-time PCR was used to characterize the distribution of rs1801274 and rs4804803 in subjects with asymptomatic dengue infection (n = 145), uncomplicated dengue (n = 67), and severe dengue (n = 36) in Morelos. In contrast with previous studies, the histidine (A) variant of rs1801274 was associated with more mild infection: carrying the histidine allele (either homozygous or heterozygous) was associated with protection from symptomatic infection compared with asymptomatic (OR 0.51, p = 0.038). Histidine homozygotes were also less likely to present severe dengue (OR 0.34, p = 0.05). Logistic regression models confirm this association (OR 0.48, p = 0.04) and also indicate that the G allele of rs4804803 is associated with symptomatic dengue (OR 2.3, p = 0.08), after accounting for other biological factors including history of infection. This variant was rare in this study population, with a frequency of 5.4%. These findings reflect the complexity of influences on the development of severe dengue infection. The inclusion of asymptomatic infections and adjusted case definitions likely do not explain the entire disparity with previous findings. Interactions with other polymorphisms may explain why the association of rs1801274 is reversed in this population compared to others. This study demonstrates the importance of genetic association studies in multiple genetically distinct populations.  相似文献   
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In an area endemic for visceral leishmaniasis, 16 patients with human immunodeficiency virus (HIV) infection developed the disease. All belonged to populations at risk for AIDS (15 were intravenous drug abusers). Five patients fulfilled the criteria for full-blown AIDS, and two more fulfilled them after diagnosis of leishmaniasis. All presented with the classic manifestations of visceral leishmaniasis, but leishmania serology was negative in 15 patients (93%). Leishmania donovani amastigotes were identified in the bone marrow in all cases. Most patients responded initially to treatment with pentavalent antimonial drugs, but seven (43%) followed a chronic course, with multiple relapses in five, despite alternative treatments. Visceral leishmaniasis occurred in patients with different levels of depression of the CD4 to CD8 lymphocyte ratio. Mortality was 37% (six patients) and was independent of the chronic-relapsing course of the disease. In no case was leishmaniasis the primary cause of death. Our data establish that visceral leishmaniasis is an opportunistic infection in HIV-infected patients, and we suggest that in endemic areas it should be considered an indicator disease for the diagnosis of AIDS.  相似文献   
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Digestive Diseases and Sciences - Autoimmune hepatitis (AIH) is a chronic liver disease able to progress to acute liver failure, cirrhosis, and liver cancer. A significant proportion of patients...  相似文献   
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Introduction

Spain, which has one of the largest migrant populations in Europe, has committed to eliminating the hepatitis C virus (HCV). The aim of this study was to estimate the prevalence of HCV among migrant groups in Spain, a country of 46 million people, with an estimated HCV-antibody prevalence of 1.7%.

Methods

Studies on HCV and migration in Spain were identified by systematically searching three databases from the first records to 30 November 2017, and consulting experts at the Ministry of Health and in the 17 Spanish autonomous communities. A meta-analysis was conducted to determine pooled HCV prevalence for the general migrant population. Prevalences were also calculated for high-risk migrant populations and populations who had undergone hospital screening, stratified by region of origin.

Results

Out of 243 studies identified, 26 met the eligibility criteria. The meta-analysis of the general migrant population found HCV antibody prevalence to be 1.6%. Migrants originating from European countries, including those at high or moderate risk for HCV, had the highest pooled prevalence (7.1%). In the general migrant population, prevalence was highest among sub-Saharan African migrants (3.1%) and lowest among Latin American migrants (0.2%).

Conclusion

Based on the limited available data, the prevalence among the general migrant population was found to be the same as the general Spanish population. Further research is needed to more accurately determine HCV prevalence for the overall migrant population and specific migrant subpopulations with a higher risk in the country as a whole and in each of Spain's 17 autonomous communities.  相似文献   
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Autoimmune hemolytic anemia (AIHA) is an infrequent group of diseases defined by autoantibody mediated red blood cell destruction. Correct diagnosis and classification of this condition are essential to provide appropriate treatment. AIHA is divided into warm and cold types according to the characteristics of the autoantibody involved and by the presence of an underlying or associated disorder into primary and secondary AIHA. Due to its low frequency, treatment for AIHA is largely based on small prospective trials, case series, and empirical observations. This review describes in detail the different treatment approaches for autoimmune hemolytic anemia. Warm antibody type AIHA should be treated with steroids, to which most patients respond, although relapse can occur and maintenance doses are frequently required. Splenectomy is an effective second line treatment and can provide long-term remission without medication. Rituximab is a useful alternative for steroid refractory patients, those requiring high maintenance doses and unfavorable candidates for surgery. Promising therapeutic modifications with this monoclonal antibody are emerging including drug combinations, lower doses, and long-term use. Primary cold agglutinin disease has been recognized as having a lymphoproliferative monoclonal origin. It is unresponsive to both steroids and splenectomy. Rituximab is currently the best therapeutic alternative for this condition, and several treatment regimens are available with variable responses.  相似文献   
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International Journal of Legal Medicine - Non-adult sex estimation is an active field of forensic inquiry as morphological variations between males and females are subtle, but observable, even from...  相似文献   
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