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21.
Weina Cheng Yazhi Wang Jingxian Liu Xiaofei Li Ming Yu Cancan Duan Liu Liu Jianyong Zhang 《Journal of applied toxicology : JAT》2022,42(6):970-980
Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity. 相似文献
22.
23.
Guoliang Zhang & Tao Xiong 《Communications In Computational Physics》2022,32(1):126-155
We propose a high order finite difference linear scheme combined with a
high order bound preserving maximum-principle-preserving (MPP) flux limiter to
solve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much less
costly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP flux
limiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guiding-center model and the incompressible Euler system. The comparison between the linear
and WENO type schemes, with and without the MPP flux limiter, will demonstrate the
good performance of our proposed approach. 相似文献
24.
目的:通过调研江苏省公立医院编内及非在编人员参加养老保险的现状,分析其存在的困境,提出相应的对策建议。方法:对江苏省内公立医院发放调研问卷,收集数据整理后运用统计分析和比较分析法描述其运营概况、编内及非在编人员参加养老保险的情况,运用公平理论分析公立医院养老保险存在的问题。结果:江苏省公立医院编内人员参加机关事业单位养老保险,非在编人员参加城镇职工养老保险;省属公立医院非在编人员占比最高;编内人员缴费基数及养老待遇均显著高于非在编人员;编内人员参加职业年金,非在编人员尚未建立年金计划。结论:树立底线公平理念,完善养老保险制度体系;改革完善非在编人员年金计划政策;建立健全参保成本财政分担机制。 相似文献
25.
宫腔积液指宫腔内液体积存(积水、积血或积脓),是绝经后女性常见体征之一,常于超声检查时发现。持续宫腔积液患者,需宫腔镜检查寻找病因。本文报道1例以宫腔积液为首发症状,经宫腔镜检查确诊为胃型宫颈腺癌的患者。通过病例回顾并文献复习,以期为更多绝经后宫腔积液及宫颈病变的诊断提供参考,避免漏诊及误诊。1病例资料患者67岁,女,主因"绝经18年,不规则阴道出血2月"于2020年5月就诊于首都医科大学附属北京妇产医院妇科微创中心。 相似文献
26.
Sung‐Hyun Hwang Myung‐Chul Kim Sumin Ji Yeseul Yang Yeji Jeong Yongbaek Kim 《Cancer science》2019,110(4):1256-1267
Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy. 相似文献
27.
Xiumei Jiang Xiaowei Zhang Patrick Gray Jiwen Zheng Timothy R. Croley Peter P. Fu 《journal of environmental science and health part c-environmental carcinogenesis & ecotoxicology reviews》2019,37(2):116-131
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability. 相似文献
28.
对中医药防治新型冠状病毒肺炎临床研究方案注册情况进行分析,为提高相关研究设计质量提供参考和建议。检索中国临床试验注册中心网站(www.chictr.org.cn)以及美国临床试验注册中心网站(clinicaltrials.gov),以新型冠状病毒肺炎、2019-nCoV等为检索词,检索新型冠状病毒肺炎中医药相关临床研究方案。按照纳入排除标准筛选文献,并提取研究注册时间、研究目的、研究类型、申办单位、研究对象、样本量、干预措施、评价指标等数据,采用描述性分析方法。共纳入新型冠状病毒肺炎中医药相关研究方案49个,研究负责单位以湖北、北京、浙江等地医院或高等院校为主。研究具体实施单位属地集中在湖北、广东、浙江、河南等地医院。研究设计以干预性试验研究为主(共40个),其中随机平行对照研究30个,非随机对照试验7个,单臂研究2个,连续入组1个;观察性研究6个;卫生服务研究2个;预防性研究1个。总样本量30562例,单个研究样本量最大20000例,最小30例。49个方案的研究对象包括健康人群(3个)、隔离观察人群(1个)、疑似病例(10个)、确诊病例(31个)、康复期病例(4个)。31个拟纳入确诊病例的研究方案中,有16个研究未明确病情分级,3个研究明确排除危重症,4个研究纳入普通型,2个研究纳入轻型、普通型或重型,1个研究纳入轻型和普通型,1个研究纳入普通型或重型,3个研究纳入重型,1个研究纳入重症或危重症。评价的干预措施包括中成药(连花清瘟胶囊/颗粒、藿香正气滴丸/口服液、八宝丹、固表解毒灵、金蒿解热颗粒、复方鱼腥草合剂、金叶败毒颗粒、疏风解毒胶囊、双黄连口服液、痰热清注射液、血必净注射液、热毒宁注射液、喜炎平注射液)、汤药、太极拳疗法。主要疗效指标以退热时间、临床症状缓解、新型冠状病毒核酸转阴、重症转化率、胸部CT影像为主。结果表明中医药防治新冠肺炎的临床研究响应快速,当前注册方案涵盖了疾病预防、治疗和康复全过程。但存在人群定义不清,研究目标不明确,干预方案需要细化,疗效评价指标需要优化等问题;另外,需要考虑疫情救治的实际困难和工作负担,在符合医学伦理条件下,优化流程,提高研究方案的可操作性。 相似文献
29.
30.
Evelyne Harkemanne Jean‐Louis Dargent Pierre‐Paul Roquet‐Gravy Audrey Bulinckx 《Pediatric dermatology》2019,36(3):365-367
We report a case of benign lymphoplasmacytic plaque (LPP) in a child. These asymptomatic erythematous papulonodular lesions are an emerging clinicopathological entity. Herein, we describe a previously unreported site for LPP lesions, namely, the volar wrist and the distal ipsilateral palm. 相似文献