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1.
《Cancer cell》2022,40(8):835-849.e8
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《Cancer cell》2021,39(9):1214-1226.e10
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目的 基于文本挖掘技术和生物医学数据库对新型冠状病毒肺炎(COVID-19)相关文献进行数据挖掘分析,探究COVID-19及其主要症状发热、咳嗽、呼吸障碍相关基因靶点,筛选潜在有效的化学药和中药。方法 使用GenCLiP 3网站获取COVID-19和其主要症状咳嗽、发热、呼吸障碍共4个关键词的共有靶点,在METASCAPE数据库中对其进行基因本体(GO)和通路富集分析,再利用String数据库和Cytoscape软件构建共有靶点的蛋白质相互作用网络,筛选获得核心基因,运用DGIdb数据库、SymMap数据库针对核心基因进行中西医治疗药物预测。结果 获得COVID-19及其主要症状共有基因靶点28个,其中有IL2、IL1B、CCL2等核心基因16个,使用DGIdb数据库筛选获得与16个关键靶点相互作用的化学药包括沙利度胺、来氟米特、环孢素等28种,中药包括虎杖、黄芪、芦荟等70味。结论 COVID-19及其主要症状的病理机制可能和CD4、KNG1、VEGFA等28个共有基因相关,可能通过介导TNF、IL-17等信号通路参与COVID-19病理过程。潜在有效药物可能通过作用相关靶点通路起到治疗COVID-19的作用。  相似文献   
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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   
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  1. The common marmoset (Callithrix jacchus) is a useful experimental animal to evaluate the pharmacokinetics of drug candidates. Cytochrome P450 (P450) 2B enzyme in marmoset livers has been identified; however, only limited information on the enzymatic properties and distribution has been available.

  2. Marmoset P450 2B6 amino acids showed high sequence identities (>86%) with those of primates including humans and cynomolgus monkeys. Phylogenetic analysis using amino acid sequences indicated that marmoset P450 2B6 was closer to human and cynomolgus monkey P450 2B6 than to P450 2B orthologs of other species, including pigs, dogs, rabbits and rodents.

  3. Quantitative polymerase chain reaction analysis using specific primers showed P450 2B6 mRNA predominantly expressed in livers among the five marmoset tissues, similar to those of humans and cynomolgus monkeys.

  4. Marmoset P450 2B6 heterologously expressed in Escherichia coli membranes oxidized 7-ethoxycoumarin, pentoxyresorufin, propofol and testosterone, at roughly similar rates to those of humans and/or cynomolgus monkeys. A high capacity of marmoset P450 2B6 with propofol 4-hydroxylation (at low ionic strength conditions) with a low Km value was relatively comparable to that for marmoset livers.

  5. These results collectively indicated a high propofol 4-hydroxylation activity of P450 2B6 expressed in marmoset livers.

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Introduction: Pharmacovigilance is essential to monitoring the safety profiles of authorized medicines. Compared with small-molecule drugs, biological drugs are more complex, more susceptible to structural variability due to manufacturing processes, and have the potential to induce immune-related reactions, underscoring the importance of safety monitoring for these products. Although highly similar to reference products, biosimilars are not expected to be structurally identical. For these reasons, proper reporting of potential adverse drug reactions (ADRs) using distinguishable names and batch numbers is essential for accurate tracing of all biological drugs. To address the need for robust pharmacovigilance, the European Parliament and Council of the European Union provided legislation regarding pharmacovigilance of biologics in 2010.

Areas covered: This narrative review examines the current state of pharmacovigilance for biologics in the European Union (EU) and discusses relevant information on pharmacovigilance of biosimilars, the current EU pharmacovigilance system, and areas that could be improved.

Expert opinion: Although steps have been taken to improve pharmacovigilance of biologics in the EU, several enhancements can still be made, including additional training for healthcare professionals on ADR reporting, the use of 2D barcodes that enhance traceability, and an open discussion of potentially missed opportunities in the pharmacovigilance of biosimilars.  相似文献   

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目的 了解铜陵市人民医院2017年临床分离细菌对抗菌药物的耐药状况。方法 对2017年1-12月临床分离菌采用纸片扩散法(KB)进行药敏试验,按CLSI 2017年版标准判读药敏试验结果,采用WHONET 5.6软件进行数据分析。结果 临床分离细菌共3436株,其中革兰阳性菌719株,占20.9%;革兰阴性菌2717株,占79.1%。耐甲氧西林金黄色葡萄球菌(MRSA)和耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)的检出率分别为23.8%和72.3%,耐甲氧西林株对β-内酰胺类抗生素和其他测试抗菌药物的耐药率显著高于甲氧西林敏感株,未发现对万古霉素和替考拉宁耐药的葡萄球菌。粪肠球菌对青霉素、氨苄西林和呋喃妥因的耐药率较低,屎肠球菌对氯霉素的耐药率较低,5.3%屎肠球菌对万古霉素耐药。大肠埃希菌、克雷伯菌属(肺炎克雷伯菌和产酸克雷伯菌)和奇异变形菌中ESBLs的检出率分别为41.4%、50.7%和19.4%。肠杆菌科细菌中克雷伯菌属和沙雷菌属对碳青霉烯类抗生素耐药率较高,分别为37.5%和36.0%,其他菌属的耐药率低于3%。鲍曼不动杆菌对亚胺培南和美罗培南的耐药率分别80.3%和79.1%;铜绿假单胞菌对亚胺培南和美罗培南的耐药率分别为29.7%和28.4%。肺炎克雷伯菌、鲍曼不动杆菌和铜绿假单胞菌中广泛耐药株的检出率分别为31.3%(171/546)、0.6%(3/508)和0.7%(3/416)。结论 本院革兰阴性菌呈增多趋势,尤其广泛耐药的肺炎克雷伯菌应引起高度关注,做好细菌耐药性监测,加强临床抗菌药物的合理使用和医院感染控制。  相似文献   
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The Theory of Rational Addictions, by Gary Becker & Kevin Murphy (1988), was a rational choice model that became a standard tool for economists modeling addictive behavior. The approach differs from other theories of addiction by modeling addictive behavior as the gradual implementation of a rational, forward‐looking plan, where consumption at any point in time is partly motivated by the immediate payoff of consumption and partly by the effects this consumption has on the individual in the future. This makes addictive behavior a subset of rational behavior, requiring no more specific government policies or attention than any other consumption choice. Later work by economists extended the theory in different ways, allowing it to match an increasing number of consumption patterns, and searched for ways to test the forward‐looking assumption in different types of market data. While the work was successful as a contribution to rational choice theory, with possible statistical applications, there are several reasons to dismiss its usefulness as an explanation of real‐world addictive behavior and its ability to assess the welfare effects of addictions.  相似文献   
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