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991.
Non-alcoholic fatty liver disease is comprised of either simple steatosis (non-alcoholic fatty liver) or a more advanced inflammatory and fibrogenic stage (non-alcoholic steatohepatitis [NASH]). NASH affects a growing proportion of the global adult and pediatric population, leading to rising rates of liver fibrosis and hepatocellular carcinoma. NASH is a multifactorial disease that is part of a systemic metabolic disorder. Here, we provide an overview of the metabolic underpinnings of NASH pathogenesis and established drivers of inflammation and fibrosis. Clarification of underlying fibrogenic and inflammatory mechanisms will advance the development of novel treatment strategies as there are no approved therapies at present. We discuss emerging experimental approaches and potential novel investigational strategies derived from animal models including the inflammasome, epigenetic reprogramming, Hippo signaling, Notch signaling, engineered T cells to remove fibrogenic HSCs, and HSC-specific targeting therapies. Recently completed and ongoing clinical trials and antifibrotics are discussed, illuminating the growing expectation that one or more therapies will yield clinical benefit in NASH in the coming years. 相似文献
992.
993.
Swapnil P. Borse Abu Sufiyan Chhipa Vipin Sharma Devendra Pratap Singh Manish Nivsarkar 《Medical principles and practice》2021,30(2):109
Type 2 diabetes mellitus (T2DM) accounts for >90% of the cases of diabetes in adults. Resistance to insulin action is the major cause that leads to chronic hyperglycemia in diabetic patients. T2DM is the consequence of activation of multiple pathways and factors involved in insulin resistance and β-cell dysfunction. Also, the etiology of T2DM involves the complex interplay between genetics and environmental factors. This interplay can be governed efficiently by lifestyle modifications to achieve better management of diabetes. The present review aims at discussing the major factors involved in the development of T2DM that remain unfocussed during the anti-diabetic therapy. The review also focuses on lifestyle modifications that are warranted for the successful management of T2DM. In addition, it attempts to explain flaws in current strategies to combat diabetes. The employability of phytoconstituents as multitargeting molecules and their potential use as effective therapeutic adjuvants to first line hypoglycemic agents to prevent side effects caused by the synthetic drugs are also discussed. 相似文献
994.
《药学学报(英文版)》2020,10(5):799-811
Overexpression of adenosine triphosphate (ATP)-binding cassette subfamily G member 2 (ABCG2) in cancer cells is known to cause multidrug resistance (MDR), which severely limits the clinical efficacy of chemotherapy. Currently, there is no FDA-approved MDR modulator for clinical use. In this study, rociletinib (CO-1686), a mutant-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), was found to significantly improve the efficacy of ABCG2 substrate chemotherapeutic agents in the transporter-overexpressing cancer cells in vitro and in MDR tumor xenografts in nude mice, without incurring additional toxicity. Mechanistic studies revealed that in ABCG2-overexpressing cancer cells, rociletinib inhibited ABCG2-mediated drug efflux and increased intracellular accumulation of ABCG2 probe substrates. Moreover, rociletinib, inhibited the ATPase activity, and competed with [125I] iodoarylazidoprazosin (IAAP) photolabeling of ABCG2. However, ABCG2 expression at mRNA and protein levels was not altered in the ABCG2-overexpressing cells after treatment with rociletinib. In addition, rociletinib did not inhibit EGFR downstream signaling and phosphorylation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). Our results collectively showed that rociletinib reversed ABCG2-mediated MDR by inhibiting ABCG2 efflux function, thus increasing the cellular accumulation of the transporter substrate anticancer drugs. The findings advocated the combination use of rociletinib and other chemotherapeutic drugs in cancer patients with ABCG2-overexpressing MDR tumors. 相似文献
995.
996.
目的研究左归降糖解郁方对糖尿病并发抑郁症大鼠海马胰岛素抵抗的调节作用。方法建立糖尿病并发抑郁症大鼠模型,并随机分为4组,模型组,阳性药组(二甲双胍0.18 g/kg+氟西汀1.8 mg/kg),左归降糖解郁方高、低剂量组(20.52、10.26g/kg),另设健康大鼠为对照组。各组大鼠ig给药28 d后,采用血糖仪及ELISA法检测空腹血糖及外周胰岛素抵抗程度。采用旷野实验和强迫游泳实验检测大鼠抑郁样行为。采用免疫荧光法和Western blotting法检测大鼠海马胰岛素受体磷酸化蛋白(p-IR)、磷酸化的胰岛素受体底物-1(p-IRS-1)的表达,采用Westernblotting法检测海马磷酸化的磷脂酰肌醇3-激酶(p-PI3K)、磷酸化蛋白激酶B(p-Akt)蛋白的表达。结果与对照组比较,模型组大鼠血糖显著升高并伴随明显的外周胰岛素抵抗,其在旷野实验中的活动次数显著降低、在强迫游泳实验中的不动时间显著延长;蛋白检测结果表明大鼠脑内p-IR、p-IRS-1、p-PI3K、p-Akt表达水平均显著降低。与模型组比较,左归降糖解郁方高剂量组大鼠血糖水平显著降低,外周胰岛素抵抗水平减轻,其在旷野实验中的活动次数显著增加、在强迫游泳实验中的不动时间显著缩短,而海马内p-IR、p-IRS-1、p-PI3K、p-Akt表达显著升高。结论左归降糖解郁方可有效调节糖尿病并发抑郁症大鼠海马胰岛素信号通路,从而改善动物脑内的胰岛素抵抗状态。 相似文献
997.
Shinichiro Muro Hironari Kato Etsuji Ishida Toru Ueki Masakuni Fujii Ryo Harada Hiroyuki Seki Ken Hirao Masaki Wato Yutaka Akimoto Masahiro Takatani Hirofumi Tsugeno Jiro Miyaike Tatsuya Toyokawa Mamoru Nishimura Naoko Yunoki Hiroyuki Okada 《Journal of gastroenterology and hepatology》2020,35(1):37-42
998.
《Clinical microbiology and infection》2018,24(7):724-731
ObjectivesUntil the introduction of fidaxomicin, antimicrobial treatment for Clostridium difficile infection (CDI) was limited to metronidazole and vancomycin. The changing epidemiology of CDI and the emergence of epidemic C. difficile PCR ribotype 027 necessitate continued surveillance to identify shifts in antibiotic susceptibility. ClosER, currently the largest pan-European epidemiological study of C. difficile ribotype distribution and antibiotic susceptibility, aimed to undertake antimicrobial resistance surveillance pre- and post-introduction of fidaxomicin.MethodsBetween July 2011 and July 2014, 39 sites across 22 European countries submitted 2830 C. difficile isolates for ribotyping, toxin testing and susceptibility testing to metronidazole, vancomycin, fidaxomicin, rifampicin, moxifloxacin, clindamycin, imipenem, chloramphenicol and tigecycline.ResultsRibotypes 027, 014, 001, 078, 020, 002, 126, 015 and 005 were most frequently isolated, and emergent ribotypes 198 and 356 were identified in Hungary and Italy, respectively. All isolates were susceptible to fidaxomicin, with scarce resistance to metronidazole (0.2%, 6/2694), vancomycin (0.1%, 2/2694) and tigecycline (0%). Rifampicin, moxifloxacin and clindamycin resistance was evident in multiple ribotypes. Lack of ribotype diversity correlated with greater antimicrobial resistance. Epidemic ribotypes (027/001) were associated with multiple antimicrobial resistance, and ribotypes 017, 018 and 356 with high-level resistance. Additional factors may also influence local ribotype prevalence.ConclusionsFidaxomicin susceptibility was retained post-introduction, and resistance to metronidazole and vancomycin was rare. Continued surveillance is needed, with more accurate classification and clarification of ribotype subtypes to further understand their role in the spread of resistance. Other factors may also influence changes in prevalence of C. difficile ribotypes with reduced antibiotic susceptibility. 相似文献
999.
R. Durand S. Bouvresse Z. Berdjane A. Izri O. Chosidow J.M. Clark 《Clinical microbiology and infection》2012,18(4):338-344
Insecticide treatment resistance is considered to be a major factor in the increasing number of infestations by head lice. The large insecticide selection pressure induced by conventional topical pediculicides has led to the emergence and spread of resistance in many parts of the world. Possible mechanisms of resistance include accelerated detoxification of insecticides by enzyme-mediated reduction, esterification, oxidation that may be overcome by synergistic agents such as piperonyl butoxide, alteration of the binding site, e.g. altered acetylcholinesterase or altered nerve voltage-gated sodium channel, and knockdown resistance (kdr). Clinical, parasitological and molecular data on resistance to conventional topical pediculicides show that treatments with neurotoxic insecticides have suffered considerable loss of activity worldwide. In particular, resistance to synthetic pyrethroids has become prominent, probably because of their extensive use. As other treatment options, including non-insecticidal pediculicides such as dimeticone, are now available, the use of older insecticides, such as lindane and carbaryl, should be minimized, owing to their loss of efficacy and safety concerns. The organophosphorus insecticide malathion remains effective, except in the UK, mostly in formulations that include terpineol. 相似文献
1000.