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1.
Taking the Chinese city of Xiamen as an example, simulation and quantitative analysis were performed on the transmissions of the Coronavirus Disease 2019(COVID-19) and the influence of intervention combinations to assist policymakers in the preparation of targeted response measures. A machine learning model was built to estimate the effectiveness of interventions and simulate transmission in different scenarios. The comparison was conducted between simulated and real cases in Xiamen. A web inter...  相似文献   
2.
目的: 探讨加替沙星(GAT)对小鼠肝脏的损伤作用及其机制。方法: 选取32只SPF级雄性昆明小鼠作为研究对象,随机分为4组:低、中、高剂量(分别为25、50、100 mg/kg) GAT组和对照组。给药体积按10 mL/kg,连续灌胃给药7 d,对照组给予对应体积的生理盐水。通过检测各组小鼠血清中的谷丙转氨酶(ALT)、谷草转氨酶(AST)、碱性磷酸酶(AKP)、肌酐(CRE)和甘油三酯(TG)浓度,初步评价加替沙星导致的小鼠肝组织损伤。进一步利用转录组测序技术检测各组小鼠肝脏的基因表达谱,筛选差异表达基因,对差异基因进行基因本体论(GO)功能分类,并采用京都基因与基因组百科全书(KEGG)数据库进行信号通路富集分析。结果: 与对照组比较,高剂量GAT组小鼠肝脏质量显著降低(P<0.01);低、中剂量GAT组肝脏系数显著降低(P<0.01);低、中剂量GAT组小鼠血清ALT浓度显著降低(P<0.05或0.01);低剂量GAT组小鼠血清AST浓度显著降低(P<0.01)。与对照组比较,中剂量GAT组共筛选出27个差异表达基因(包括20个上调基因,7个下调基因)。GO功能分类提示这些基因主要富集在免疫系统、多细胞生物、多生物及生殖过程等17个生物过程中。KEGG通路分析提示差异基因主要富集于脂质代谢、萜类化合物和聚酮化合物的代谢等22条通路中。结论: GAT可导致小鼠肝功能发生变化,并通过影响小鼠肝脏内胆汁酸和胆固醇等内分泌系统和脂质代谢等的平衡,造成肝组织损伤。  相似文献   
3.
《Cancer cell》2022,40(10):1223-1239.e6
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4.
电离辐射会对人体造成损伤,根据受照剂量、时间等因素的不同可诱发多种生物效应。目前对于低剂量辐射产生的健康效应仍有争议,筛选对低剂量敏感的辐射响应生物标志物,对于完善低剂量辐射生物效应机制、拓宽低剂量辐射在临床中的应用均具有重要理论意义。综述探讨各核糖核酸(RNA)在低剂量辐射反应中的变化及其对辐射敏感性的调节作用,同时评估各RNA作为低剂量辐射响应标志物的潜力。  相似文献   
5.
《Ticks and Tick》2022,13(2):101904
Equine piroplasmosis is a tick-transmitted disease that is considered one of the most serious infectious diseases affecting equines. Searching for novel antipiroplasm drugs remains indispensable due to the emergence and spreading of resistant piroplasm parasites against the limited currently used drugs, diminazene aceturate and imidocarb dipropionate. Therefore, novel drugs with specified targets need to be identified and exploited. The inhibitory effects of Medicines for Malaria Venture (MMV) Malaria Box compounds with potent in vitro anti-equine piroplasmosis activity were evaluated against the growth of B. microti in mice in this study. Using a nested PCR assay targeting the B. microti ss-rRNA gene, we investigated the far-reaching impacts of effective combinations to inhibit parasite recrudescence. Using real-time PCR, this study revealed potential targets for the found potent compounds. When used as monotherapy, screening the Malaria Box against the in vivo growth of the B. microti parasite resulted in the discovery of new, potent antipiroplasm medicines, such as MMV020275 and MMV020490. In MMV020275-treated Theileria equi in vitro culture, a statistically significant difference (P<0.05) in the cGMP-dependent protein kinase (PKG) mRNA level was identified as a down-regulation in contrast to non-treated cultures. In conclusion, new potent antipiroplasm drugs, including MMV020275 and MMV020490 are identified. MMV020275 significantly down-regulate the mRNA levels of the PKG gene. Clofazimine enhanced the inhibitory efficacy of MMV compounds which is suggested to use in treatment of animal or human babesiosis in the future.  相似文献   
6.
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   
7.
ObjectiveTo detect the Epstein-Barr virus (EBV) viral load of children after hematopoietic stem cell transplantation (HSCT) using chip digital PCR (cdPCR).MethodsThe sensitivity of cdPCR was determined using EBV plasmids and the EBV B95-8 strain. The specificity of EBV cdPCR was evaluated using the EBV B95-8 strain and other herpesviruses (herpes simplex virus 1, herpes simplex virus 2, varicella zoster virus, human cytomegalovirus, human herpesvirus 6, and human herpesvirus 7). From May 2019 to September 2020, 64 serum samples of children following HSCT were collected. EBV infection and the viral load of serum samples were detected by cdPCR. The epidemiological characteristics of EBV infections were analyzed in HSCT patients.ResultsThe limit of detection of EBV cdPCR was 110 copies/mL, and the limit of detection of EBV quantitative PCR was 327 copies/mL for the pUC57-BALF5 plasmid. The result of EBV cdPCR was up to 121 copies/mL in the EBV B95-8 strain, and both were more sensitive than that of quantitative PCR. Using cdPCR, the incidence of EBV infection was 18.75% in 64 children after HSCT. The minimum EBV viral load was 140 copies/mL, and the maximum viral load was 3,209 copies/mL using cdPCR. The average hospital stay of children with EBV infection (184 ± 91 days) was longer than that of children without EBV infection (125 ± 79 days), P = 0.026.ConclusionEBV cdPCR had good sensitivity and specificity. The incidence of EBV infection was 18.75% in 64 children after HSCT from May 2019 to September 2020. EBV cdPCR could therefore be a novel method to detect EBV viral load in children after HSCT.  相似文献   
8.
9.
《Vaccine》2019,37(31):4310-4317
ONRAB® is a human adenovirus rabies glycoprotein recombinant vaccine developed to control rabies in wildlife. To support licensing and widespread use of the vaccine, safety studies are needed to assess its potential residual impact on wildlife populations. We examined the persistence of the ONRAB® vaccine virus in captive rabies vector and non-target mammals. This research complements work on important rabies vector species (raccoon, striped skunk, and red fox) but also adds to previous findings with the addition of some non-target species (Virginia opossum, Norway rats, and cotton rats) and a prolonged period of post vaccination monitoring (41 days). Animals were directly inoculated orally with the vaccine and vaccine shedding was monitored using quantitative real-time PCR applied to oral and rectal swabs. ONRAB® DNA was detected in both oral and rectal swabs from 6 h to 3 days post-inoculation in most animals, followed by a resurgence of shedding between days 17 and 34 in some species. Overall, the duration over which ONRAB® DNA was detectable was shorter for non-target mammals, and by day 41, no animal had detectable DNA in either oral or rectal swabs. All target species, as well as cotton rats and laboratory-bred Norway rats, developed robust humoral immune responses as measured by competitive ELISA, with all individuals being seropositive at day 31. Similarly, opossums showed good response (89% seropositive; 8/9), whereas only one of nine wild caught Norway rats was seropositive at day 31. These results support findings of other safety studies suggesting that ONRAB® does not persist in vector and non-target mammals exposed to the vaccine. As such, we interpret these data to reflect a low risk of adverse effects to wild populations following distribution of ONRAB® to control sylvatic rabies.  相似文献   
10.
《Vaccine》2019,37(43):6255-6261
Health workers represent an important target group for seasonal influenza vaccination because of their increased risk of infection as well as the risk of transmitting infection to vulnerable patients in the health care setting. Moreover, seasonal vaccination of health workers contributes to pandemic preparedness. However, many countries, especially in Africa and Asia, do not have policies for health worker influenza vaccination. In countries where such policies exist, vaccination coverage is often low. The World Health Organization (WHO) is developing a manual to guide the introduction of seasonal influenza vaccination of health workers. An Independent External Advisory Group (IEAG) that is advising WHO on the content of the manual met to discuss issues that are relevant and often unique to health worker vaccination. This meeting report summarizes the main issues that were discussed and the outcomes of the discussion. The issues include policy considerations, including the evidence in support of health worker vaccination; categorization and prioritization of health workers; the choice of vaccination strategy; its integration into broader health worker vaccination and occupational health policies; planning and management of vaccination, particularly the approaches for communication and demand generation; and the challenges with monitoring and evaluation of health worker vaccination, especially in low and middle-income countries.  相似文献   
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