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991.
Terminal deletions of the chromosome 6q27 region are rare genomic abnormalities, linked to specific brain malformations and other neurological phenotypes. Reported cases have variable sized genomic deletions that harbor several genes including the DLL1 and TBP. We report on an inherited 0.38 Mb terminal deletion of chromosome 6q27 in a 22‐week fetus with isolated bilateral ventriculomegaly and her affected mother using microarray‐based comparative genomic hybridization and fluorescent in situ hybridization (FISH). The deleted region harbors at least seven genes including DLL1 and TBP. The affected mother had a history of hydrocephalus, developmental delay, and seizures commonly associated with DLL1 and TBP 6q27 deletions. This deletion is one of the smallest reported isolated 6q27 terminal deletions. Our data provides additional evidence that haploinsufficiency of the DLL1 and TBP genes may be sufficient to cause the ventriculomegaly, seizures, and developmental delays associated with terminal 6q27 deletions, indicating a plausible role in the abnormal development of the central nervous system.  相似文献   
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目的调查深圳市某小学一起水痘疫情的流行特征,探讨其危险因素。方法按照病例定义搜索病例,描述疾病的三间分布并开展危险因素现场调查分析。结果 2012年11月30日至2013年1月9日共搜索到符合病例定义的病例22例,首例病例发病时间为11月15日,未隔离;疫情报告日期和发病高峰为11月30日;对新发病例严格执行隔离措施,末例病例为12月19日。17例病例为一年级(6)班学生,该班罹患率为33.3%(17/51),另有4例其它班级病例与该班首发病例在同一午托室休息。一年级(6)班未接种组的罹患率为100%(4/4),接种组为33.3%(13/39),水痘疫苗的4年保护率为66.7%。结论未尽早隔离首发病例、及时报告是此次疫情的主要危险因素,及时发现新发病例、严格执行隔离措施可有效控制疫情。疫苗保护效果还需深入开展评价。  相似文献   
994.
The International Agency for Research on Cancer has classified diesel engine exhaust (DEE) as a human lung carcinogen. Given that inflammation is suspected to be an important underlying mechanism of lung carcinogenesis, we evaluated the relationship between DEE exposure and the inflammatory response using data from a cross‐sectional molecular epidemiology study of 41 diesel engine testing workers and 46 unexposed controls. Repeated personal exposure measurements of PM2.5 and other DEE constituents were taken for the diesel engine testing workers before blood collection. Serum levels of six inflammatory biomarkers including interleukin (IL)‐1, IL‐6, IL‐8, tumor necrosis factor (TNF)‐α, macrophage inflammatory protein (MIP)‐1β, and monocyte chemotactic protein (MCP)‐1 were analyzed in all subjects. Compared to unexposed controls, concentrations of MIP‐1β were significantly reduced by ~37% in DEE exposed workers (P < 0.001) and showed a strong decreasing trend with increasing PM2.5 concentrations in all subjects (Ptrend < 0.001) as well as in exposed subjects only (Ptrend = 0.001). Levels of IL‐8 and MIP‐1β were significantly lower in workers in the highest exposure tertile of PM2.5 (>397 µg/m3) compared to unexposed controls. Further, significant inverse exposure‐response relationships for IL‐8 and MCP‐1 were also found in relation to increasing PM2.5 levels among the DEE exposed workers. Given that IL‐8, MIP‐1β, and MCP‐1 are chemokines that play important roles in recruitment of immunocompetent cells for immune defense and tumor cell clearance, the observed lower levels of these markers with increasing PM2.5 exposure may provide insight into the mechanism by which DEE promotes lung cancer. Environ. Mol. Mutagen. 59:144–150, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
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996.
Epstein‐Barr virus detection using nasopharyngeal swabs has been suggested as a potential screening test that could improve the specificity of current EBV‐based serological assays. However, application requires insertion of the swab deep into the nasopharynx, a procedure not amenable to non‐clinic screening. We reasoned that swabbing the more easily accessible nasal cavity might provide an appealing alternative for NPC detection. Patients > 18 years of age diagnosed with histologically confirmed NPC were recruited from the Otolaryngology Department at the National Taiwan University Hospital. ENT clinicians collected both nasal and nasopharyngeal swabs. EBV DNA and cellular beta‐globulin DNA were quantified using quantitative PCR targeting a highly‐conserved region of the BKRF1 gene. EBV DNA was detectable (non‐zero) in all 34 nasopharyngeal swabs and above the positivity threshold of 1666 EBV copies in 30 (88.2%) patients. EBV DNA was detectable in 50% of 34 nasal swabs and above the positivity threshold in four (11.8%) patients. Average EBV DNA levels were >3‐fold higher (P < 0.001) in nasopharyngeal compared to nasal swabs. Among the 17 NPC patients with detectable EBV DNA in both swab types, we observed correlation (P < 0.01) between EBV DNA measurements. Our data represent the first evaluation of EBV DNA collected from nasal swabs. Given current EBV DNA amplification techniques, nasopharyngeal swabs remain more sensitive than nasal swabs for NPC detection.  相似文献   
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A newly developed dengue virus vaccine (chimeric yellow fever virus‐tetravalent dengue vaccine [CYD‐TDV]) has recently been licensed for clinical use. The World Health Organization recommends vaccination for populations with seroprevalence of at least 70% to maximize public health impact. This study aimed to delineate the seroprevalence of dengue infection in Hong Kong. A total of 105 972 serum samples submitted for clinical testing during the period 2013‐2015 were age‐stratified and sex‐stratified. For each year of collection, 25 samples were randomly selected from each age‐sex group. Altogether, 2100 samples were tested for the dengue immunoglobulin G (IgG) antibody using a non‐type–specific ELISA kit. The overall dengue IgG‐positive rate was 4.6% and showed no significant change over the 3 years. The positive rate was not associated with sex, but a steep rise in seroprevalence for persons above 65 years (32.7%) was observed. The low dengue seroprevalence in Hong Kong does not support implementation of a national immunization program. Majority of the population in Hong Kong are susceptible to dengue infection, and a substantial proportion of persons older than 65 years could acquire secondary infection and are prone to develop severe dengue.  相似文献   
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