Diatom-inspired multiscale mineralization of patterned protein–polysaccharide complex structures

Marine diatoms construct their hierarchically ordered, three-dimensional (3D) external structures called frustules through precise biomineralization processes. Recapitulating the remarkable architectures and functions of diatom frustules in artificial materials is a major challenge that has important technological implications for hierarchically ordered composites. Here, we report the construction of highly ordered, mineralized composites based on fabrication of complex self-supporting porous structures—made of genetically engineered amyloid fusion proteins and the natural polysaccharide chitin—and performing in situ multiscale protein-mediated mineralization with diverse inorganic materials, including SiO₂, TiO₂ and Ga₂O₃. Subsequently, using sugar cubes as templates, we demonstrate that 3D fabricated porous structures can become colonized by engineered bacteria and can be functionalized with highly photoreactive minerals, thereby enabling co-localization of the photocatalytic units with a bacteria-based hydrogenase reaction for a successful semi-solid artificial photosynthesis system for hydrogen evolution. Our study thus highlights the power of coupling genetically engineered proteins and polysaccharides with biofabrication techniques to generate hierarchically organized mineralized porous structures inspired by nature.     

基于微芯片电泳-电化学方法的细胞内谷胱甘肽分析

建立微芯片电泳-电化学检测技术分析细胞内还原型（GSH）和氧化型（GSSG）谷胱甘肽的新方法. 分别考察缓冲液pH值、缓冲液浓度、SDS浓度、分离电压、进样时间、检测电位等因素对GSH、GSSG分离检测的影响. 在最优实验条件下,在3 min内实现GSH和GSSG的有效分离和检测. GSH和GSSG的线性范围分别为5.0~200.0 μmol/L和2.0~100.0 μmol/L（R²>0.99）,最低检测限（S/N≥3）分别为4.87 μmol/L和1.98 μmol/L. 最终将所建立的方法应用于细胞样品中2种物质含量的测定,结果令人满意.     

乳清蛋白与运动营养

当今竞技体育对运动员的体能要求越来越高，普通膳食蛋白质的质量已不能满足训练和比赛的需要，乳清蛋白是一类利用先进工艺从牛奶中提取的蛋白质，它具有很高的生物学价值，它对运动能力的影响主要表现为；提供长时问运动时骨骼肌的能量供应；促进蛋白合成和肌肉增长；清除自由基和抗氧化性；提高机体免疫能力和延缓中枢疲劳，乳清蛋白是一种理想的运动营养食品，它在运动营养中将发挥越来越重要的作用。     

血睾酮与运动

运动应激中下丘脑—垂体—性腺轴(HPG轴)功能低下或紊乱,使睾酮合成降低。其原因可能既有调节因素的变化,也有睾丸间质细胞内一些独立因素的变化。大强度运动早期血睾酮水平上升,随时间延长而下降,而皮质醇水平上升,有人提出用睾酮/皮质醇来评定机体的机能状况。血睾酮的作用机制以及运动引起的血睾酮变化的机制仍不完全清楚,尚待进一步研究。     

蛋白质芯片技术及生物医学应用

蛋白质芯片技术是一种新型蛋白质分析技术。文章介绍了研究它的目的和意义,重点介绍它的研制过程和研究内容以及生物医学应用。     

蛋白质芯片技术的研究进展

蛋白质芯片技术是采用微阵列方法，对样品中蛋白质进行高通量、高灵敏度分析的技术。它不仅是蛋白质组学研究中强有力的工具，也是临床应用中疾病早期诊断、预后和治疗效果评测的新手段，其研究成果拓展了与人类健康更加贴近的应用领域。本文较为全面地介绍了蛋白质芯片技术的原理和分类、固相基质和蛋白质的固定、信号检测等方面的进展。     

口腔颌面部恶性肿瘤患者血清免疫抑制酸性蛋白的研究

为探讨免疫抑制酸性蛋白 (IAP)检测在口腔颌面部恶性肿瘤中的临床应用价值 .采用单向免疫扩散法检测了 6 8例口腔颌面部恶性肿瘤患者及 30例正常对照的血清 IAP.结果表明 :正常人血清 IAP含量为 (346± 10 7) μg/ m L,口腔颌面部恶性肿瘤患者血清 IAP为 (6 73± 149) μg/ m L,两者相比有显著性差异 (P<0 .0 1) ;肿瘤患者的 IAP阳性率高达 85.3% (58/ 6 8) , - 期患者血清IAP水平明显高于 - 期患者 (P<0 .0 1) ,随着临床分期的增加 ,IAP水平也随之增高 ;口腔颌面部鳞癌与唾液腺癌之间 IAP水平无显著性差异 (P>0 .0 5) ;治疗后血清 IAP水平明显下降 (P<0 .0 1) ,复发者血清 IAP复又回升 ,而未复发者 IAP水平处于正常水平 .说明检测口腔颌面部恶性肿瘤患者血清 IAP有助于监视病情的发展、观察疗效及判断预后 ,动态研究可监测肿瘤的复发与转移 .     

膜蛋白三维结构研究的新突破——线粒体呼吸链膜蛋白复合物II结构解析

由清华大学-中科院生物物理所结构生物学联合研究小组完成的"线粒体呼吸链膜蛋白复合物Ⅱ的晶体结构"研究成果以Article的方式发表在2005年7月1日出版的Cell上.本文介绍了该项成果的研究背景、意义、主要创新点及方法.     

运动训练对自发性高血压大鼠心肌细胞凋亡蛋白表达的影响

目的:研究运动训练对SHR心肌细胞中HSP-72、Bcl-2和蛋白激酶β(PKB)、Bax、糖原合成激酶-3(GSK-3)的影响,以探讨其对运动引起心肌细胞凋亡的作用。方法:以SHR大鼠中等强度训练为实验模型,采用Western bloting技术检测了大鼠心肌细胞中调控蛋白HSP-72、Bcl-2和蛋白激酶β(PKB)、Bax、糖原合成激酶-3(GSK-3)的表达。结果:长期中等强度训练可以提高心肌细胞中抑凋亡蛋白HSP-72、Bcl-2和蛋白激酶β(PKB)的表达,凋亡蛋白Bax、糖原合成激酶-3(GSK-3)表达显著降低,Bcl-2/Bax的表达没有显著变化,从而抑制心肌细胞的凋亡。结论:心肌细胞中HSP-72、Bcl-2和蛋白激酶β(PKB)、Bax、糖原合成激酶-3(GSK-3),Bcl-2/Bax在运动后的不同表达对心肌细胞凋亡的发生有明显的抑制作用。     

Mechanism of Antidiabetic Action of Compound GII Purified from Fenugreek (<Emphasis Type="Italic">Trigonella foenum graecum</Emphasis>) Seeds

To study the mechanism of action of water soluble compound GII purified from fenugreek (Trigonella foenum graecum) seeds which was shown earlier to have antidiabetic effect in the subdiabetic, moderately and severely diabetic rabbits. In rabbits (1–1.5 kg bw) diabetes was induced by intravenous injection of 80 mg/kg bw of alloxan. They were fed with GII at a dose of 50 mg/kg bw daily once in the morning for 15 days in the subdiabetic and moderately diabetic and 30 days in the severely diabetic rabbits. Serum total cholesterol (TC), triglycerides (TG), LDL + VLDL cholesterol [(LDL + VLDL)C], HDL cholesterol [(HDL)C], total tissue lipids, glycogen and enzymes of carbohydrate metabolism (glycolysis, gluconeogenesis, polyol pathway) hexokinase, glucokinase, pyruvate kinase, malic enzyme, glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, aldose reductase and sorbitol dehydrogenase and antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase were estimated. Liver and kidney function parameters were also estimated. Treatment with GII for 15 days in the subdiabetic and moderately diabetic rabbits and for 30 days in the severely diabetic rabbits (i) decreased the elevated lipids TC, TG, (LDL + VLDL)C and increased the decreased (HDL)C, (ii) decreased the elevated liver and heart total lipids, TC and TG, (iii) increased the decreased liver and muscle glycogen, (iv) increased the decreased hexokinase, glucokinase, pyruvate kinase, malic enzyme, glucose-6-phosphate dehydrogenase, superoxide dismutase, glutathione peroxidase, (v) decreased the increased glucose-6-phosphatase, sorbitol dehydrogenase, aldose reductase. Results thus show that treatment with GII compound purified from fenugreek seeds for 15 days in the subdiabetic and moderately diabetic and 30 days in the severely diabetic rabbits corrects the altered serum lipids, tissue lipids, glycogen, enzymes of glycolysis, gluconeogenesis, glycogen metabolism, polyol pathway and antioxidant enzymes. Histopathological abnormalities (fatty infiltration and other cellular changes) seen in the pancreas, liver, heart and kidneys were repaired after treatment with GII. In fact partially damaged pancreas was repaired. Liver and kidney function test results were normal in the GII treated animals indicating that GII treatment is safe and free from any side effects.