牛磺酸对苯并芘体外诱导血小板聚集活化功能的影响

取健康志愿者外周静脉血并分离血小板,采用随机分组的方式将血小板分成6组。通过检测血小板最大聚集率、膜表面CD62P及PAC-1阳性表达率,探讨不同浓度的牛磺酸(Tau)对苯并芘(BAP)体外诱导血小板聚集活化功能的影响。结果表明,血小板最大聚集率在二磷酸腺苷( ADP)和胶原诱导下各浓度BAP-Tau组与溶剂对照组之间比较差异均有统计学意义(P<0．01)。血小板膜表面CD62P、PAC-1表达率BAP-Tau高浓度组与溶剂对照组比较差异有统计学意义(P<0．01)。不同浓度的Tau均可拮抗BAP致血小板功能损伤的作用,且呈浓度梯度性变化。     

Fat burners: nutrition supplements that increase fat metabolism

The term 'fat burner' is used to describe nutrition supplements that are claimed to acutely increase fat metabolism or energy expenditure, impair fat absorption, increase weight loss, increase fat oxidation during exercise, or somehow cause long-term adaptations that promote fat metabolism. Often, these supplements contain a number of ingredients, each with its own proposed mechanism of action and it is often claimed that the combination of these substances will have additive effects. The list of supplements that are claimed to increase or improve fat metabolism is long; the most popular supplements include caffeine, carnitine, green tea, conjugated linoleic acid, forskolin, chromium, kelp and fucoxanthin. In this review the evidence for some of these supplements is briefly summarized. Based on the available literature, caffeine and green tea have data to back up its fat metabolism-enhancing properties. For many other supplements, although some show some promise, evidence is lacking. The list of supplements is industry-driven and is likely to grow at a rate that is not matched by a similar increase in scientific underpinning.     

牛磺酸纳米乳的制备及稳定性考察

[目的]研究牛磺酸纳米乳的处方、制备及稳定性考察。[方法]通过滴定法绘制伪三元相图,根据相图优选处方,并初步考察牛磺酸纳米乳的稳定性、粒径分布和理化性质。[结果]确定纳米乳处方为十四酸异丙酯(IPM):司盘-80∶吐温-80∶水=4∶4∶6∶1。牛磺酸纳米乳平均粒径为30.8 nm。[结论]牛磺酸纳米乳制备方法简单,性质稳定。     

HR‐MAS MRS of the pancreas reveals reduced lipid and elevated lactate and taurine associated with early pancreatic cancer

The prognosis for patients with pancreatic cancer is extremely poor, as evidenced by the disease's five‐year survival rate of ~5%. New approaches are therefore urgently needed to improve detection, treatment, and monitoring of pancreatic cancer. MRS‐detectable metabolic changes provide useful biomarkers for tumor detection and response‐monitoring in other cancers. The goal of this study was to identify MRS‐detectable biomarkers of pancreatic cancer that could enhance currently available imaging approaches. We used ¹H high‐resolution magic angle spinning MRS to probe metabolite levels in pancreatic tissue samples from mouse models and patients. In mice, the levels of lipids dropped significantly in pancreata with lipopolysaccharide‐induced inflammation, in pancreata with pre‐cancerous metaplasia (4 week old p48‐Cre;LSL‐Kras^G12D mice), and in pancreata with pancreatic intraepithelial neoplasia, which precedes invasive pancreatic cancer (8 week old p48‐Cre LSL‐Kras^G12D mice), to 26 ± 19% (p = 0.03), 19 ± 16% (p = 0.04), and 26 ± 10% (p = 0.05) of controls, respectively. Lactate and taurine remained unchanged in inflammation and in pre‐cancerous metaplasia but increased significantly in pancreatic intraepithelial neoplasia to 266 ± 61% (p = 0.0001) and 999 ± 174% (p < 0.00001) of controls, respectively. Importantly, analysis of patient biopsies was consistent with the mouse findings. Lipids dropped in pancreatitis and in invasive cancer biopsies to 29 ± 15% (p = 0.01) and 26 ± 38% (p = 0.02) of normal tissue. In addition, lactate and taurine levels remained unchanged in inflammation but rose in tumor samples to 244 ± 155% (p = 0.02) and 188 ± 67% (p = 0.02), respectively, compared with normal tissue. Based on these findings, we propose that a drop in lipid levels could serve to inform on pancreatitis and cancer‐associated inflammation, whereas elevated lactate and taurine could serve to identify the presence of pancreatic intraepithelial neoplasia and invasive tumor. Our findings may help enhance current imaging methods to improve early pancreatic cancer detection and monitoring. Copyright © 2014 John Wiley & Sons, Ltd.     

Analysis of ileal sodium/bile acid cotransporter and related nuclear receptor genes in a family with multiple cases of idiopathic bile acid malabsorption

INTRODUCTION Bile acids are synthesized from cholesterol in the liver and secreted into the small intestine, where they facilitate absorption of fat, fat-soluble vitamins and cholesterol[1]. The bile acids are then reabsorbed from the intestine and return…     

牛磺酸对大鼠胰岛素抵抗高血压的影响

目的探讨牛磺酸对胰岛素抵抗高血压大鼠的影响。方法在输注胰岛素和葡萄糖引起动物胰岛素抵抗高血压模型上，测量平均动脉压、心率、血糖，放射免疫法测定血浆胰岛素和内皮素及主动脉组织内皮素，用２－脱氧葡萄糖摄取评估骨骼肌葡萄糖转运活性，用乙醇沉淀法测定肌糖原合成，测定肝胰岛素清除。结果胰岛素抵抗高血压大鼠血压升高，心率加快，血糖和血浆胰岛素含量增加（Ｐ＜０．０１）。牛磺酸治疗可明显改善上述指标，并增加骨骼肌葡萄糖转运活性，促进肌糖原合成和肝胰岛素清除，同时减轻血浆和主动脉内皮素含量。结论牛磺酸治疗胰岛素抵抗高血压大鼠是有效的。     

牛磺酸滴眼液的渗透压考察及其影响因素分析

目的:了解牛磺酸滴眼液的渗透压现状及处方组成对其影响情况。方法:采用SMC-30B渗透压摩尔浓度测定仪,采用冰点下降法对国内5个厂家牛磺酸滴眼液进行渗透压摩尔浓度测定。结果:多数牛磺酸滴眼液的渗透压均高出人眼可耐受的渗透压范围,处方组成的不合理是造成渗透压超标的主要因素。结论:牛磺酸滴眼液的渗透压现状亟待解决,其处方组成需要进一步研究改进。     

牛磺酸对肾NRK-52E细胞缺氧/复氧损伤的保护及初步机制

目的观察牛磺酸(Tau)对NRK-52E细胞缺氧/复氧(H/R)损伤的保护作用及初步机制。方法用NRK-52E细胞缺氧8 h复氧12 h培养建立了H/R模型,流式细胞仪检测凋亡率和胞内游离钙离子浓度,RT-PCR和Western blot检测GRP78、Caspase-12、Caspase-3 mRNA和蛋白表达。结果与对照组比较,H/R组细胞凋亡率上升,GRP78、Caspase-12及Caspase-3 mRNA和蛋白表达均明显增高(P<0.01),胞质游离钙离子浓度也升高(P<0.01);与H/R组比较,各浓度牛磺酸处理组的细胞Caspase-3活性和凋亡率明显下降,胞质游离钙和GRP78、Caspase-12及Caspase-3 mRNA和蛋白表达均有明显降低(P<0.01)。结论牛磺酸对NRK-52E细胞H/R损伤有较好的抑制作用,且呈一定的剂量依赖性,其机制可能是调节胞内钙稳态、抑制GRP78、Caspase-12及Caspase-3表达,减少了细胞凋亡。     

Taurine and vitamin C influence 8-nitroguanine brain expression following sub-chronic arsenic exposure in the mouse

BACKGROUND： Arsenic-induced overproduction of reactive nitrogen species results in damage to biomacromolecules in tissues. This is one of major mechanisms of toxic effects due to arsenic. It is assumed that taurine and vitamin C prevent overproduction of peroxynitrite （ONOO） and resist arseniasis by decreasing oxygen-free radical production. OBJECTIVE： To investigate the intervention effects of taurine and vitamin C on 8-nitroguanine （8-NO2-G） expression in the brain of mice exposed to arsenic. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Department of Occupational and Environmental Health, Dalian Medical University, China between March 2007 and July 2008. MATERIALS： As203, taurine, and vitamin C （Sigma, USA）, rabbit polyclonal anti-8-NO2-G antibody and goat anti-rabbit IgG （Dojindo, Japan） were used in this study. METHODS： A total of 40 healthy, Kunming mice were equally and randomly assigned to four groups Mice in the As203 group received drinking water containing 4 mg/L As2O3. Mice in the taurine and vitamin C groups received 150 mg/kg taurine and 45 mg/kg vitamin C, respectively, by gavage, twice per week, and simultaneously received As2O3. Mice in the control group were administered normal drinking water. MAIN OUTCOME MEASURES： Histopathological changes in brain tissues of mice were observed by hematoxylin-eosin staining. 8-NO2-G expression in brain tissues was determined by immunohistochemistry. RESULTS： Abnormal, histopathological changes were observed in brain tissue of mice from the As2O3 group, which included axonal loss, cell shrinkage, and karyolysis. The above-described changes were minimal in the taurine and vitamin C groups. 8-NO2-G expression was significantly greater in brain tissue from the As2O3 group compared with the control group （P 〈 0.05）, however, weak 8-NO2-G expression was observed in the taurine and vitamin C groups. CONCLUSION： Taurine or vitamin C protected against pathological changes and nucleic acid damage due to reactive nitrogen species in brain tissue of mice exposed to arsenic.