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自从20世纪90年代确认马兜铃酸具有肾毒性以来,已有部分药材被禁用;但由于部分含马兜铃酸药物的不可替代性,仍然应用于临床。围绕马兜铃酸肾毒性及其毒性机制展开了诸多研究,本文对马兜铃酸肾毒性机制研究进行综述,以期为临床合理运用含马兜铃酸类中草药及预防中药药源性肾损伤提供参考。  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) is the steatosis of liver parenchyma unrelated to alcoholism, autoimmunity, and viral infection. It is also a metabolism-related syndrome, which has an unseparated relationship with adipose tissue dysfunction and obesity. Hepatic encephalopathy (HE) is one of the severe complications of chronic liver disease and one of the end-stage syndromes of liver disease. Some researchers have suggested that NAFLD, like other forms of liver injury, may be related to the metabolic disorder of branched-chain amino acids (BCAAs), which have been approved to be associated with HE influencing ammonia and energy metabolism. However, several studies have revealed the relationship among amino acids in serum, HE, and chronic liver disease; there are few studies on the contents of amino acids in brain tissues of an animal model with NAFLD. In the present research, we established a NAFLD mouse model with C57BL/6 mice and determined the contents of 13 amino acids in brain tissues of model mice by HPLC-FLD derivatization method using ortho-phthalaldehyde (OPA) to explore the relationship between the contents of amino acids in brain tissues and the progression of NAFLD. Moreover, the study showed that the changes of amino acid contents in the brain of the C57BL/6 mice were associated with the advancement of NAFLD, and this change might be related to the mechanism of HE.  相似文献   
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目的建立牛蛙血细胞核酸及脊髓运动神经细胞显色方法,更好地服务教学和临床。方法制备临时装片,用福尔根反应和甲基绿-派洛宁对细胞内的核酸进行显色,用甲苯胺蓝染液对脊髓运动神经细胞进行染色。结果福尔根反应后,细胞核呈紫红色,细胞质呈绿色。该反应的最适条件为室温水解2 min,60℃水解8 min,再室温水解2 min,复染40 s。甲基绿-派洛宁染色后,细胞核呈蓝色,细胞质呈粉红色。甲苯胺蓝染色后,脊髓运动神经细胞被染成深蓝色。结论福尔根反应中亮绿复染的最适时间为40 s。甲基绿-派洛宁能够对细胞内的DNA和RNA同时进行定位、定性分析。该研究方法对实验教学、科学研究和临床实践具有一定的理论和实际意义。  相似文献   
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Lipids are essential for cellular functioning considering their role in membrane composition, signaling, and energy metabolism. The brain is the second most abundant organ in terms of lipid concentration and diversity only after adipose tissue. However, in the central system (CNS) lipid dysregulation has been linked to the etiology, progression, and severity of neurodegenerative diseases such as Alzheimeŕs, Parkinson, and Multiple Sclerosis. Advances in the human genome and subsequent sequencing technologies allowed us the study of lipidomics as a promising approach to diagnosis and treatment of neurodegeneration. Lipidomics advances rapidly increased the amount and quality of data allowing the integration with other omic types as well as implementing novel bioinformatic and quantitative tools such as machine learning (ML). Integration of lipidomics data with ML, as a powerful quantitative predictive approach, led to improvements in diagnostic biomarker prediction, clinical data integration, network, and systems approaches for neural behavior, novel etiology markers for inflammation, and neurodegeneration progression and even Mass Spectrometry image analysis. In this sense, by exploiting lipidomics data with ML is possible to improve the identification of new biomarkers or unveil new molecular mechanisms associated with lipid impairment across neurodegeneration. In this review, we present the lipidomic neurobiology state-of-the-art highlighting its potential applications to study neurodegenerative conditions. Also, we present theoretical background, applications, and advances in the integration of lipidomics with ML. This review opens the door to new approaches in this rising field.  相似文献   
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Bile acids (BAs) are classically known to play a vital role in the metabolism of lipids and in absorption. It is now well established that BAs act as signaling molecules, activating different receptors (such as farnesoid X receptor, vitamin D receptor, Takeda G-protein-coupled receptor 5, sphingosine-1-phosphate, muscarinic receptors, and big potassium channels) and participating in the regulation of energy homeostasis and lipid and glucose metabolism. In addition, increased BAs can impair cardiovascular function in liver cirrhosis. Approximately 50% of patients with cirrhosis develop cirrhotic cardiomyopathy. Exposure to high concentrations of hydrophobic BAs has been shown to be related to adverse effects with respect to vascular tension, endothelial function, arrhythmias, coronary atherosclerotic heart disease, and heart failure. The BAs in the serum BA pool have relevant through their hydrophobicity, and the lipophilic BAs are more harmful to the heart. Interestingly, ursodeoxycholic acid is a hydrophilic BA, and it is used as a therapeutic drug to reverse and protect the harmful cardiac effects caused by hydrophobic elevated BAs. In order to elucidate the mechanism of BAs and cardiovascular function, abundant experiments have been conducted in vitro and in vivo. The aim of this review was to explore the mechanism of BAs in the cardiovascular system.  相似文献   
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Nonalcoholic fatty liver disease(NAFLD)is a broad-spectrum disease,ranging from simple hepatic steatosis to nonalcoholic steatohepatitis,which can progress to cirrhosis and liver cancer.Abnormal hepatic lipid accumulation is the major manifestation of this disease,and lipotoxicity promotes NAFLD progression.In addition,intermediate metabolites such as succinate can stimulate the activation of hepatic stellate cells to produce extracellular matrix proteins,resulting in progression of NAFLD to fibrosis and even cirrhosis.G protein-coupled receptors(GPCRs)have been shown to play essential roles in metabolic disorders,such as NAFLD and obesity,through their function as receptors for bile acids and free fatty acids.In addition,GPCRs link gut microbiota-mediated connections in a variety of diseases,such as intestinal diseases,hepatic steatosis,diabetes,and cardiovascular diseases.The latest findings show that gut microbiota-derived acetate contributes to liver lipogenesis by converting dietary fructose into hepatic acetyl-CoA and fatty acids.GPCR agonists,including peptides and natural products like docosahexaenoic acid,have been applied to investigate their role in liver diseases.Therapies such as probiotics and GPCR agonists may be applied to modulate GPCR function to ameliorate liver metabolism syndrome.This review summarizes the current findings regarding the role of GPCRs in the development and progression of NAFLD and describes some preclinical and clinical studies of GPCR-mediated treatment.Overall,understanding GPCR-mediated signaling in liver disease may provide new therapeutic options for NAFLD.  相似文献   
10.
肝脏屏障是肝脏抵御外源性有害物质侵袭的主要结构,在维持肝脏分泌功能,调控胆汁转运及细胞间信息传递中发挥重要作用。内毒素、炎性因子及胆汁酸等诱发肝脏屏障蛋白改变及屏障功能障碍,可能参与结肠炎性肝病发生。探究结肠炎对肝脏屏障的影响及机制,从肝脏屏障角度阐释结肠炎性肝病的发生机制有望为其防治提供线索和依据。  相似文献   
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