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41.
Two hundred forty-eight human immunodeficiency virus (HIV)-positive and 496 HIV-negative subjects in Uganda were tested by HerpeSelect herpes simplex virus type 2 enzyme-linked immunosorbent assay (ELISA) and Western blotting to optimize the ELISA for use in this population. A higher index cutoff value was required for optimal sensitivity and specificity, and overall performance of the assay was not affected by HIV status.  相似文献   
42.
A 64-year-old male with Aspergillus fumigatus infection that had disseminated from the lung to the ankle and adjacent bone was treated successfully with posaconazole after therapy with itraconazole and amphotericin B lipid complex failed. Marked clinical improvement occurred within 6 weeks of initiation of posaconazole therapy; after 6 months, infection had resolved at all sites. The patient has had no recurrence of infection.  相似文献   
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Pediatric cardiomyopathies can be caused by variants in genes encoding the sarcomere and cytoskeleton in cardiomyocytes. Variants are typically inherited in an autosomal dominant manner with variable expressivity. De novo variants have been reported, however their overall frequency is largely unknown. We sought to determine the rate of de novo, pathogenic and likely pathogenic (P/LP) variants in children with a diagnosis of hypertrophic, dilated, or restrictive cardiomyopathy (HCM, DCM, or RCM), and to compare disease outcomes between individuals with and without a de novo variant. A retrospective record review identified 126 individuals with HCM (55%), DCM (37%), or RCM (8%) ≤18 years of age who had genetic testing. Overall, 50 (40%) had positive genetic testing and 18% of P/LP variants occurred de novo. The rate of de novo variation in those with RCM (80%) was higher than in those with HCM (9%) or DCM (20%). There was evidence of germline mosaicism in one family with RCM. Individuals with de novo variants were more likely than those without to have a history of arrhythmia (p = .049), sudden cardiac arrest (p = .024), hospitalization (p = .041), and cardiac transplantation (p = .030). The likelihood of de novo variation and impact on family risk and screening should be integrated into genetic counseling.  相似文献   
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Influenza A virus replicates in the respiratory epithelium and induces an inflammatory infiltrate comprised of mononuclear cells and neutrophils. To understand the development of the cell-mediated immune response to influenza and how leukocyte trafficking to sites of inflammation is regulated, we examined the chemokine expression pattern in lung tissue from A/PR/8/34-infected C57BL/6 mice using an RNase protection assay. Monocyte chemoattractant protein 1, macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, MIP-3alpha, regulated on activation, normal T expressed and secreted (RANTES), MIP-2, and interferon-inducible protein 10 (IP-10) mRNA expression was up-regulated between days 5 and 15 after infection, consistent with a role for these chemokines in leukocyte recruitment to the lung. Low levels of expression were detected for the CC chemokine receptors (CCR)2 and CCR5, whereas CXC chemokine receptor (CXCR)3 was significantly up-regulated by day 10 after infection, coinciding with peak inflammatory cell infiltration in the airways. As RANTES, IP-10, and their receptors were up-regulated during influenza virus infection, we investigated leukocyte recruitment and viral clearance in mice deficient in RANTES or CXCR3, the receptor for IP-10. Leukocyte recruitment and viral replication in influenza-infected RANTES knockout(-/-) mice were similar to that in control mice, showing that RANTES is not essential for the immune response to influenza infection. Similarly, leukocyte recruitment and viral replication in CXCR3-/- mice were identical to control mice, except at day 8 postinfection, where fewer lymphocytes, neutrophils, and eosinophils were detected in the bronchoalveolar lavage of CXCR3-/- mice. These studies suggest that although the chemokines detected may play a role in regulating leukocyte trafficking to the lung during influenza infection, some may be functionally redundant.  相似文献   
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Serologic assays that utilize herpes simplex virus (HSV) type-specific glycoproteins G-1 (HSV-1) and G-2 (HSV-2) to discriminate between antibodies against HSV-1 and HSV-2 are sensitive and specific. However, the high rates of seroreversion, defined as the change in an individual's antibody status from positive to negative over time, previously reported in longitudinal evaluations of glycoprotein G type-specific tests suggests that their use in HSV acquisitional studies would be problematic. To further explore the reliability of the glycoprotein G-based serologic tests, we evaluated HSV-1 and HSV-2 enzyme immunoassays from Focus Technologies in a longitudinal cohort of 1207 young women from Pittsburgh, Pa. On enrollment of the women in the study, HSV-1 and HSV-2 antibodies were detected in 46.6 and 24.9% of the women, respectively. Among the women with at least three visits, 3.4% (15 of 447) of those who were HSV-1 antibody positive had a subsequent negative result while fewer than 1% (2 of 227) of those who were HSV-2 antibody positive seroreverted. The median of mean positive index values for women who seroreverted to HSV-1 antibody was lower than that for women who remained seropositive (1.25 versus 7.06; P < 0.001). Similarly, the median of mean positive index values for women whose HSV-2 antibody status reverted from positive to negative was lower than that for those women who did not serorevert (1.83 versus 7.46; P = 0.02). Comparative Western blot analysis demonstrated that the lower positive index values, seen more often among the HSV seroreverters, often signified false-positive immunoassay results. Overall, the seroreversion rates were low; the use of glycoprotein G-based serologic tests for the measurement of HSV-1 and HSV-2 antibodies in incidence studies therefore appears warranted.  相似文献   
48.
Group C rotavirus associated with fatal enteritis in a family outbreak   总被引:21,自引:0,他引:21  
A family outbreak of gastroenteritis involving three adults and three children is described in which diarrhoea and vomiting were the main clinical features. One infant died in whom no pathogens could be detected in either small or large intestinal postmortem samples. Stool samples from two symptomatic siblings contained rotaviruses as demonstrated by electron microscopy. Both of these faecal samples were negative when assayed in a group A specific rotavirus enzyme-linked immunosorbent assay (ELISA) and subsequent genomic analysis of these rotaviruses was suggestive of group C rotavirus. Serological evidence showed that these atypical rotaviruses were members of serogroup C. Other atypical rotaviruses in faecal samples from sporadic cases in symptomatic children were detected over a similar time period and location. These had electrophoretic RNA profiles similar to those in the family outbreak. Furthermore, seroepidemiological studies detected group C rotavirus antibody in blood donors resident in the location of the family outbreak.  相似文献   
49.
PCR-SSOP identification procedures for IL-2, IL-6, IL-10, TNF-alpha and TNF-beta cytokine polymorphisms have been developed. Application of the procedures to a range of diverse geographically distributed populations has identified ethnic differences within the groups studied. Five populations were investigated, Northern Ireland, South African Zulu, Omani, Singapore Chinese and Mexican Mestizos.  相似文献   
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