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BackgroundHeavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as μg/g wet weight.ResultsHeavy metal concentrations in muscle ranged between:(0.054–0.109), (0.260–1.043), (0.264–0.897), (5.895–11.898), (0.381–0.970), (13.582–29.133) and (0.332–0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1.ConclusionThis study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks.  相似文献   
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According to conservative estimates, >230 million people are infected with schistosomiasis,which becomes one of the most common parasitic diseases. This study focuses on investigating in vivo and in vitro effects of mmu-miR-92a-2-5p in Schistosoma japonicum-induced liver fibrosis by targeting TLR2. Through bioinformatic analysis, the overexpression of TLR2 and the down-regulation of mmu-miR-92a-2-5p were revealed in the progression of S. japonicum-induced liver fibrosis. BALB/C mice were taken advantage to construct normal control and schistosomiasis liver fibrosis (SLF) model. The mice in model groups were transfected recombinant lentivirus (Lenti-mmu-miR-92a-2-5p or Lenti-NC) to alter the expression of mmu-miR-92a-2-5p in vivo. HE and Masson staining were employed to observe the pathological changes and collagenous fibrosis. QRT-PCR showed that mmu-miR-92a-2-5p was decreased while TLR2 was elevated in the infected groups. However, lenti-mmu-miR-92a-2-5p group could inhibit liver fibrosis. Then the effect of mmu-miR-92a-2-5p on S. japonicum-induced liver fibrosis including cell apoptosis rates, proliferation and proteins related to liver fibrosis was examined in NIH-3T3 mouse embryonic fibroblasts. Moreover, the association between mmu-miR-92a-2-5p and TLR2 was detected by dual-luciferase reporter gene assay and the expression of cytokines IL-4, IFN-γ and TNF-α in SLF model was detected by ELISA. Further, the knockout of TLR2 in C57BL/6J mice was used to confirm the association between mmu-miR-92a-2-5p and TLR2. Thus, these findings demonstrated that mmu-miR-92a-2-5p inhibited S. japonicum-induced liver fibrosis by targeting TLR2 in vitro and in vivo.  相似文献   
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《Vaccine》2022,40(44):6397-6403
Mumps virus (MuV) is highly neurotropic and neurovirulent, hence, the neurovirulence of virus seeds used in the production of mumps vaccines must be tested. The previous neurovirulence evaluation method involves measuring the area of the cavity in the Lewis neonatal rat brain caused by MuV through paraffin sectioning and hematoxylin-eosin (HE) staining. However, the processes of paraffin sectioning and HE staining are time consuming and complicated. To solve this problem, in this study, a vibratome sectioning system was first deployed to evaluate MuV neurovirulence in the rat brain instead of paraffin sectioning and HE staining. The results showed that the vibratome sectioning method could assess the neurovirulence potential of MuV more objectively and efficiently. In addition, the effects of different MuV doses and the ages of the rats in days on this evaluation method were explored. The results indicate that MuV at no less than 10 50 % cell culture infective dose (CCID50) could cause obvious cavity formation in 1-day-old rat brains. The neonatal rat model developed in this study could evaluate the neurovirulence of different MuV strains with high sensitivity and good repeatability.  相似文献   
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目的 为了对2004年浙江省报告的输入性疑似登革热病例查明病因,从分子水平分析流行毒株的生物学特征,追踪传染源,为疾病的预防控制提供实验室依据。方法 对疑似患者血清标本采用ELISA、IFA和荧光RT—PCR方法分别检测登革病毒IgM、IgG抗体和病毒核酸,并用C6/36和BHK-21细胞分离登革病毒。采用RT—PCR方法扩增病毒E基因和NS1基因后分别进行序列测定,并与不同国家和地区的登革热毒株进行同源性和进化树分析。结果 从患者血清中检测到登革病毒IgM、IgG抗体和登革2型病毒核酸,并分离到登革2型病毒;浙江省登革2型病毒分离株(ZJ/01/04)与登革2型国际标准株Jamaica、国内Fujian/10/99株和Saudi/92株在E基因上氨基酸的同源性分别为97.1%、99.2%和99.6%,而与登革1、3、4型毒株相同区域氨基酸同源性分别为68.7%、66.9%和63.6%。基因进化树显示ZJ/OI/04分离株与Saudi/92株亲缘关系最近,在进化树的同一分支上。结论 从病原学、血清学和分子生物学特征上均证实该输入病例是由登革2型病毒引起,该毒株最有可能来源于沙特阿拉伯。  相似文献   
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TaqMan荧光定量RT-PCR快速检测登革1、2型病毒   总被引:1,自引:0,他引:1  
目的 建立特异、灵敏、快速的荧光定量RT—PCR方法用于检测登革1、2型病毒核酸,并初步应用于登革热的临床标本检测。方法 根据GenBank登录的登革热毒株序列。应用生物学软件进行序列比对,分别在登革病毒1型的NS5基因和2型的C基因的保守区设计特异性引物和TaqMan探针。对荧光定量RT—PCR反应条件进行优化,验证该方法的特异性、灵敏度和稳定性。同时对疑似登革热病例血清标本进行检测。结果 该方法对登革1、2型病毒的检测有高度的特异性,与登革病毒的4个血清型之间以及流行性乙型脑炎病毒、肾综合征出血热病毒等均无交叉反应,检测的灵敏度均达0.1TCID50,可从疑似登革热病例血清标本中直接检测登革病毒核酸,从病毒核酸提取至完成检测仅需3h左右。结论 本研究建立的TaqMan荧光定量RT—PCR是一种快速检测登革1、2型病毒特异、敏感的方法,适用于临床早期诊断。  相似文献   
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目的:研究建立农村职业中毒控制快速响应网络的有效性。资料:来源于国家相关法律、法规对职业中毒响应的要求,象山县疾病预防控制中心职业中毒调查资料和突发公共卫生事件处置工作实践。结果:建立农村职业中毒控制快速响应网络,提高和改善了应急处置能力和条件,加快了中毒事件报告、处置响应速度,对中毒人员的现场医学急救和医院救治及时有效,中毒的监督监测、预警及健康教育效果明显。讨论:分析农村职业中毒控制快速响应体系建立的有效性,中毒快速响应的及时性和规范性,基层实施现场医学救治和医院专业治疗结合的重要性,预防性措施是防止中毒发生和减轻中毒危害的基础。结论:建立农村职业中毒控制快速响应网络可行、有效,且十分必要。  相似文献   
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ObjectivesSarcopenia and metabolic syndrome (MetS) are associated with the prognosis from malignant tumors. However, evidence of the relationship between sarcopenia and MetS among gastric cancer (GC) patients following radical gastrectomy is lacking. This study assessed the association between preoperative sarcopenia and MetS among GC patients and analyzed the prognosis of patients with different malnutrition statuses.MethodsWe prospectively assessed the preoperative statuses of sarcopenia and MetS among patients who underwent radical gastrectomy from July 2014 to December 2017. We combined sarcopenia and MetS to generate four groups: MetS-related sarcopenia group (MSS), sarcopenia group (S), MetS group (MS), and normal group (N).ResultsA total of 749 patients with resectable GC were included in this study. Preoperative MetS was associated with sarcopenia (p < 0.001). Multivariate logistic regression presented that MetS-related sarcopenia (OR = 2.445; p = 0.010) and sarcopenia alone (OR = 2.117; p = 0.001) were independent predictors of grade Ⅱ and above complications, while MetS alone was not (p = 0.342). Cox regression analysis revealed that MetS-related sarcopenia led to the worst prognosis in the four groups (MSS vs MS: HR = 3.555, p < 0.001; MSS vs N: HR = 2.020, p = 0.003; MSS vs S: HR = 1.763, p = 0.021). However, the MetS group had better prognosis than the normal group (MS vs N: HR = 0.568, p = 0.048).ConclusionPreoperative MetS was associated with sarcopenia among GC patients. MetS-related sarcopenia resulted in a significantly worse prognosis. The long-term prognoses of patients with sarcopenia were impaired by preoperative MetS, while patients without sarcopenia benefited. Thus, patients with both sarcopenia and MetS require more medical interventions.  相似文献   
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