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81.
The prevalence of type 2 diabetes (T2D) is rapidly increasing worldwide. Obesity, physical inactivity and ageing increase the risk of T2D. Epigenetic modifications can change due to environmental exposures and may thereby predispose to disease. This review aims at summarizing recent advances in epigenetics related to T2D, with a special focus on impaired insulin action and secretion in humans. There will be an emphasis on analyses in human tissues; both from T2D case‐control cohorts and intervention studies. Current data support an important role for epigenetics in the pathogenesis of T2D. Numerous studies have found differential DNA methylation and gene expression in skeletal muscle, adipose tissue, the liver and pancreatic islets from subjects with T2D compared with nondiabetic controls. For example, PDX1 has increased DNA methylation and decreased expression in pancreatic islets from patients with T2D compared with nondiabetic controls. Nongenetic risk factors for T2D such as ageing, unhealthy diets and physical activity do also impact the epigenome in human tissues. Interestingly, physical activity altered DNA methylation of candidate genes for T2D such as THADA in muscle and FTO, KCNQ1 and TCF7L2 in adipose tissue. There is also a strong interaction between genetic and epigenetic factors that together seem to affect T2D. mQTL studies in human adipose tissue and pancreatic islets showed that SNPs associated with DNA methylation levels in numerous sites. Several of these SNPs are also associated with T2D. Recent data also support that DNA methylation of some sites in blood may be developed into biomarkers that predict T2D since methylation of, for example TXNIP, ABCG1 and SREBF1 associated with future T2D. Future studies should use this information for development of new therapies and biomarkers and thereby improve prediction, prevention and treatment of T2D and its complications.  相似文献   
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目的 系统评价生长抑素及其类似物联合质子泵抑制剂(proton pump inhibitor,PPI)治疗急性非静脉曲张性上消化道出血(acute non-variceal upper gastrointestinal bleeding,ANVUGIB)的有效性和安全性,并分析其用药经济性。方法 采用循证医学方法搜集生长抑素及其类似物联合PPI治疗ANVUGIB的RCT、队列研究进行meta分析,得到相应的有效性及安全性分析结果,并进行成本-效果分析。结果 最终纳入6个RCT均未接受内镜治疗,共610例受试者。Meta分析结果显示,生长抑素及其类似物联合高、中、低剂量PPI治疗在以下方面均优于单用高、中、低剂量PPI治疗,差异有统计学意义,总有效率[OR=3.34,95%CI(2.03,5.47),P<0.000 01]、止血时间[MD=-9.04,95%CI(-11.69,-6.38),P<0.000 01]、输血量[MD=-1.10,95%CI(-1.46,-0.74),P<0.000 01];在不良反应发生率方面,2组差异无统计学意义[OR=0.49,95%CI(0.11,2.12),P=0.34]。ANVUGIB患者予生长抑素联合高、中、低剂量奥美拉唑与单用高、中、低剂量奥美拉唑进行成本-效果分析,增量成本效果比分别为172.28,217.26,330.37,敏感性分析后显示结果稳定。而接受内镜治疗后应用生长抑素及其类似物联合PPI治疗仅1个队列研究,研究结果显示内镜治疗成功后联合治疗并不优于PPI单药治疗。结论 现有证据表明,生长抑素及其类似物联合PPI治疗未经内镜治疗的ANVUGIB患者为较有效的方案,两者安全性相当、耐受性较好,从药品直接成本考虑,高剂量PPI组联合治疗较中、低剂量PPI组联合治疗更具有成本效果性。而对于经内镜下止血治疗的患者两者疗效相当,可考虑单用PPI。  相似文献   
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Background

In depression, excessive glucocorticoid action may cause maladaptive brain changes, including in the pathways controlling energy metabolism. Insulin and glucagon-like peptide-1 (GLP-1), besides regulation of glucose homeostasis, also possess neurotrophic properties. Current study was aimed at investigating the influence of prenatal stress (PS) on insulin, GLP-1 and their receptor (IR and GLP-1R) levels in the hypothalamus. GLP-1 and GLP-1R were assayed also in the hippocampus and frontal cortex – brain regions mainly affected in depression. The second objective was to determine the influence of exendin-4 and insulin on CRH promoter gene activity in in vitro conditions.

Methods

Adult male PS rats were subjected to acute stress and/or received orally glucose. Levels of hormones and their receptors were assayed with ELISA method. In vitro studies were performed on mHypoA-2/12?hypothalamic cell line, stably transfected with CRH promoter coupled with luciferase.

Results

PS has reduced GLP-1 and GLP-1R levels, attenuated glucose-induced increase in insulin concentration and increased the amount of phosphorylated IR in the hypothalamus of animals subjected to additional stress stimuli, and also decreased the GLP-1R level in the hippocampus. In vitro studies demonstrated that insulin is capable of increasing CRH promoter activity in the condition of stimulation of the cAMP/PKA pathway in the applied cellular model.

Conclusion

Prenatal stress may act as a preconditioning factor, affecting the concentrations of hormones such as insulin and GLP-1 in the hypothalamus in response to adverse stimuli. The decreased GLP-1R level in the hippocampus could be linked with the disturbances in neuronal plasticity.  相似文献   
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目的探讨急性非静脉曲张性上消化道出血采用大剂量质子泵抑制剂治疗的疗效。方法将本院2015年6月—2018年6月期间的急性非静脉曲张性上消化道出血患者60例进行分组研究,对照组30例给予常规剂量质子泵抑制剂治疗,观察组30例给予大剂量质子泵抑制剂治疗,对治疗效果等相关指标进行分析。结果观察组治疗效果以及生活质量评分与对照组相比较高,止血时间、输血量、住院时间以及不良反应发生率与对照组想比较低,P<0.05。结论大剂量质子泵抑制剂治疗急性非静脉曲张性上消化道出血效果较好,有助于提高患者生活质量。  相似文献   
88.
根据国家标准GB9706.27-2005中的规定,使用天平对注射泵和输液泵工作数据的准确性进行测试。采用称重法测量输注设备的准确性,通过对数据的获取与处理,生成喇叭曲线,计算百分比误差A和B。目前,国内外尚没有自动化程度较高的产品,本研究拟利用一台PC电脑和多串口卡,使用Python编程开发工具,可同时对多台天平进行实时的数据获取、存储、显示、处理及结果判定,最后一键打印原始记录,实现闭环式检测过程。  相似文献   
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郑园园  王健  蒋剑平  周迪夷  任菁菁 《中草药》2020,51(6):1586-1592
目的探究玄参多糖对2型糖尿病大鼠糖脂代谢及肝胰岛素信号通路的影响。方法采用链脲佐菌素(STZ)注射法制备糖尿病大鼠模型,随机分成5组,分别为模型组、阳性药二甲双胍(200 mg/kg)组及玄参多糖低、中、高剂量(80、160、320 mg/kg)组,另设同周龄普通饲料喂养大鼠为对照组;ig给药6周后监测各组大鼠体质量及生存状态、空腹血糖(FBG)、血脂[总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)]、肝功能[丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)]、肾功能[肌酐(CREA)、血尿素氮(BUN)]、糖化血红蛋白(GHb)、空腹血清胰岛素(FINS)、C-肽、超氧化物歧化酶(SOD)、丙二醛(MDA)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)等指标的变化;HE染色和油红O染色评估大鼠肝脏病理学变化及脂肪变性;Western blotting法检测肝胰岛素信号通路相关蛋白表达。结果玄参多糖能回升2型糖尿病大鼠体质量,改善代谢功能,降低大鼠FBG、GHb、ALT、AST、CREA、BUN、TC、TG、LDL-C、MDA水平,升高HDL-C、FINS、C-肽、SOD、CAT、GSH-Px水平;Western blotting结果表明玄参多糖能活化IRS-2/PI3K/Akt信号通路,升高过氧化物酶体增殖物激活受体γ(PPAR-γ)、葡萄糖转运蛋白4(GLUT-4)表达水平。结论玄参多糖能够改善2型糖尿病大鼠糖脂代谢,其机制可能跟调控肝胰岛素信号通路有关。  相似文献   
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Objective: To evaluate the effects of Chinese medicine Dingkun Pill (定坤丹) alone or in combination with Diane-35 on patients with polycystic ovary syndrome (PCOS). Methods: This is a prospective randomized controlled trial conducted at Peking Union Medical College Hospital Beijing, China, from December 2016 to September 2017. Totally 117 PCOS patients were randomly assigned to the Dingkun Pill group (38 cases), Diane-35 group (40 cases), or combined group (39 cases). Patients in the Dingkun Pill group or Diane-35 group took daily 7 g of oral Dingkun Pill or 1 tablet of oral Diane-35, respectively, for 21 consecutive days followed by 7 drug-free days. And the combined group received a combination of Dingkun Pill and Diane-35. The treatment course was 3 months. Fasting plasma glucose and insulin, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), free fatty acids (FFA) and sex hormones were analyzed, quantitative insulin sensitivity check index (QUICKI) was calculated, and menstruation and acne scores were recorded at baseline and after 3-month treatment. Results: Compared with before treatment, QUICKI decreased significantly in the Dingkun Pill and combined groups after 3-month treatment (P<0.05); TC, LDL-C and FFA decreased significantly in the Dingkun Pill group (P<0.01), LDL-C also decreased obviously in the Diane-35 group (P<0.01), while TC increased significantly in the combined group (P<0.01), TG increased significantly in all groups (P<0.01); total testosterone (TT) and menstruation regularity was improved significantly in the Diane-35 and combined groups (P<0.01); acne scores were improved in all groups (P<0.01). After treatment, TC and FFA in the Dingkun Pill group were significantly lower than the Diane-35 group (P<0.05 or P<0.01); TT was lower and regular menstruation rate was higher in the Diane-35 and combined groups than the Dingkun Pill group (P<0.01), and no differences were observed between Diane-35 group and combined group (P>0.05). Conclusions: Dingkun Pill showed better effects than Diane-35 in improving insulin sensitivity, lowering TC and FFA. Diane-35 was more efficient in regulating menstruation and lowering androgen than Dingkun Pill. Combination of Dingkun Pill and Diane-35 may be a better choice to regulate menstruation, lower androgens while improve glucose metabolism in PCOS patients. (Registered on ClinicalTrials.gov, registration No. NCT03264638)  相似文献   
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