Recent advances in elucidating the biological properties of Withania somnifera and its potential role in health benefits

Withania somnifera (L.) Dunal (Solanaceae), also known as ashwagandha, is an important medicinal plant that is widely used as a home remedy for several diseases in the Indian subcontinent and other parts of the world. W. somnifera is a dietary supplement composed of various nutrients, polyphenols and alkaloids that have free radical scavenging capacity, as well as other chemical constituents that possess anti-inflammatory, antitumor, anti-stress, antioxidant, immunomodulatory, and rejuvenating properties. The mechanism of action for these properties are not fully understood. W. somnifera also appears to influence the endocrine, cardiopulmonary and central nervous systems. Toxicity studies reveal that W. somnifera can be used without side effects. The findings presented in this review are very encouraging and indicate that this herb should be studied more extensively to confirm these results and to reveal other potential therapeutic effects.     

Proteomic analysis of secretion from human transplanted submandibular gland replacing lacrimal gland with severe keratoconjunctivitis sicca

Purpose: Proteomic analysis of secretions from transplanted or non-transplanted submandibular glands in patients with severe keratoconjunctivitis sicca and tears from normal eyes. Experimental design: Secretions from submandibular glands transplanted to replace lacrimal glands and non-transplanted submandibular glands were collected at 1 year from 5 patients with severe keratoconjunctivitis sicca undergoing transplantation, and tears were collected from 3 normal subjects. 2-D electrophoresis (2-DE), then mass spectrometry was used to identify proteins. Western blot analysis was used to confirm protein expression. Results: We identified 34 and 11 distinct proteins in the saliva from transplanted submandibular glands and tears, respectively. The saliva from transplanted submandibular glands contained almost all the proteins abundant in tear fluid. The functions of identified proteins in the saliva from transplanted submandibular gland were mainly immune response and anti-bacterial. In total, 7 proteins showed differential expression between the saliva of transplanted and non-transplanted submandibular glands. The upregulation of short palate, lung and nasal epithelium carcinoma-associated protein 2 and carbonic anhydrase VI was confirmed by Western blot analysis. Conclusions: Identified proteins in saliva from transplanted submandibular glands may protect ocular structures. These findings can help in understanding the functional status of transplanted submandibular glands.     

食管鳞癌组织中CDC2、CLDN5蛋白表达及其临床病理意义的研究

目的探讨CDC2及CLDN5在食管鳞癌中表达及其临床病理特征的关系。方法应用免疫组化Elivision法检测90例食管鳞癌组织、28例正常食管黏膜组织及16例重度不典型增生组织中CDC2和CLDN5的蛋白表达情况。结果在食管鳞癌和正常食管黏膜组织中CDC2和CI。DN5的阳性表达率分别为88．89％（80／90）、85．56％（77／90）和48．86％（12／28）、25．00％（7／28）,两者差异有统计学意义（P〈O．05）。CDC2蛋白表达在低分化食管鳞癌中明显高于高分化食管鳞癌;临床分期Ⅲ＋Ⅳ期组的CDC2蛋白的表达显著高于I期、Ⅱ期组（P〈O．05）。CDC2和CLDN5在食管鳞癌中表达呈正相关（r=0．537,P〈o．05）。结论CDC2和CLDN5在食管鳞癌的发生、发展过程中可能发挥重要作用,可能作为食管癌临床早期诊断的重要指标。     

不同强度运动对大鼠心肌细胞凋亡的影响

通过比较不同强度负荷运动中大鼠心肌细胞的凋亡及其相关基因B细胞淋巴瘤-2(Bcl-2)表达变化的实验研究,试图找出它们之间相互关系的一般规律,为训练制定合理的、适宜的运动负荷提供理论依据.采用8周龄雄性SD大鼠30只,随机分为安静对照组(NC)、中等强度运动组(ME)和大强度运动组(HE),测定心肌细胞的凋亡指数和相关基因B细胞淋巴瘤-2,采用HE染色法观察心肌细胞.结果表明:中等强度运动组和大强度运动组的心肌都有细胞凋亡现象.中等强度运动组的心肌细胞凋亡指数显著升高且差异具有显著性意义(P<0.05),不同强度运动组差异无统计学意义.3组均有Bcl-2表达,中等强度运动组和安静对照组相比具有极显著性差异(P<0.01),大强度运动组和安静对照组相比有显著性差异(P<0.05),大强度运动组表达显著低于中等强度运动组(P<0.05).不适宜的运动负荷会造成大鼠心肌细胞凋亡增加,并且可能参与心肌的损害过程.     

Gene expression in Eucalyptus branch wood with marked variation in cellulose microfibril orientation and lacking G-layers

In response to gravitational stresses, angiosperm trees form tension wood in the upper sides of branches and leaning stems in which cellulose content is higher, microfibrils are typically aligned closely with the fibre axis and the fibres often have a thick inner gelatinous cell wall layer (G-layer). Gene expression was studied in Eucalyptus nitens branches oriented at 45 degrees using microarrays containing 4900 xylem cDNAs, and wood fibre characteristics revealed by X-ray diffraction, chemical and histochemical methods. Xylem fibres in tension wood (upper branch) had a low microfibril angle, contained few fibres with G-layers and had higher cellulose and decreased Klason lignin compared with lower branch wood. Expression of two closely related fasciclin-like arabinogalactan proteins and a beta-tubulin was inversely correlated with microfibril angle in upper and lower xylem from branches. Structural and chemical modifications throughout the secondary cell walls of fibres sufficient to resist tension forces in branches can occur in the absence of G-layer enriched fibres and some important genes involved in responses to gravitational stress in eucalypt xylem are identified.     

微生物燃料电池阳极产电微生物和阴极受体特性及研究进展

介绍微生物燃料电池的基本工作原理。根据电子传递方式阳极产电微生物分为无需中间体微生物和需中间体微生物。对阴极进行不同反应所涉及的最终电子受体进行了概述,并展望了微生物燃料电池的应用前景。     

Differential invertase activity and root growth between Cu-tolerant and non-tolerant populations in Kummerowia stipulacea under Cu stress and nutrient deficiency

There has been no study on key enzymes in sucrose cleavage in metallophyte plants so far, which may be crucial for the plants’ root growth and heavy-metal tolerance maintenance. Here, we tested the hypothesis that the roots of copper tolerant plants should manifest a higher activity of acid invertases that are rate-limiting in sucrose catabolism than non-tolerant plants both for supporting growth and for their maintaining tolerance under Cu stress. Two populations of Kummerowia stipulacea, one from an ancient waste heap at a Cu mine, and the other from a non-contaminated site, were used in the experiments. The plants were grown in 1/2-fold (control) or 1/20-fold (nutrient deficiency) Hoagland’ solution, with (Cu stress) or without (control) 10 μmol/L Cu²⁺. Plants from the mine proved to be of Cu tolerance. Cu exposure had a stronger inhibition on root growth and thus resulting in a lower root/shoot ratio in the plants of non-mine population compared to the mine population. Cu exposure showed a stronger inhibition of acid invertase activity of Cu non-tolerant plants than Cu-tolerant plants, while neutral/alkaline invertase was insensitive to Cu. A positive correlation between the activity of acid invertases and the root growth and root/shoot ratio was observed. The results indicated an important role of acid invertases in governing root growth and root/shoot biomass allocation in the plants of mine population. The results also suggested that the higher activities in acid invertases of mine population plants might at least partly associate with the plants’ Cu tolerance, and their higher activities in acid invertases in turn played an role in maintenance of the Cu tolerance by supplying carbon and energy for tolerance mechanisms. In addition, the results showed evidence that neutral/alkaline invertase might play a role in compensating for the depression in sucrose catabolism due to Cu-induced inhibition in acid invertases.     

Prediction of phosphotyrosine signaling networks using a scoring matrix-assisted ligand identification approach

Systematic identification of binding partners for modular domains such as Src homology 2 (SH2) is important for understanding the biological function of the corresponding SH2 proteins. We have developed a worldwide web-accessible computer program dubbed SMALI for scoring matrix-assisted ligand identification for SH2 domains and other signaling modules. The current version of SMALI harbors 76 unique scoring matrices for SH2 domains derived from screening oriented peptide array libraries. These scoring matrices are used to search a protein database for short peptides preferred by an SH2 domain. An experimentally determined cut-off value is used to normalize an SMALI score, therefore allowing for direct comparison in peptide-binding potential for different SH2 domains. SMALI employs distinct scoring matrices from Scansite, a popular motif-scanning program. Moreover, SMALI contains built-in filters for phosphoproteins, Gene Ontology (GO) correlation and colocalization of subject and query proteins. Compared to Scansite, SMALI exhibited improved accuracy in identifying binding peptides for SH2 domains. Applying SMALI to a group of SH2 domains identified hundreds of interactions that overlap significantly with known networks mediated by the corresponding SH2 proteins, suggesting SMALI is a useful tool for facile identification of signaling networks mediated by modular domains that recognize short linear peptide motifs.     

Ultrasound-assisted hydrolysis and acidogenesis of solid organic wastes in a rotational drum fermentation system

The hydrolysis and acidogenesis of solid organic wastes in a rotational drum fermentation system (RDFS) were improved by direct ultrasonic irradiation (DUSI) and a modified ultrasonic treatment (MUST) composed of dilution, ultrasonic irradiation, and filtration. The effect of DUSI on VA desorption from particle surfaces was estimated. DUSI delivered few distinctions from the broth characteristics, but elevated pH and VS degradation rate (53% higher than the control) in the subsequent acidogenesis. The results demonstrated that DUSI could dislodge VA from particle surfaces and disrupt large-size particles by hydro-mechanical shear force. To improve VA desorption and removal, a MUST process was constructed. The influences of MUST on the characteristics of the fermentation broth and the subsequent acidogenic performance were investigated. MUST raise the broth pH level from 5.1 to 5.5 and remarkably decreased VA concentration from 11.0 to 3.5g/L. At the end of the subsequent acidogenesis, VA increasing ratios, VS degradation ratios, and surface based hydrolysis constants of the fermentors with the control broth (CF) and the treated broth (MUSTF) were 166.7% and 732.0%, 17.0% and 26.7%, and 16.9% and 26.8x10(-6)kgm(-2)d(-1), respectively. With the assistance of MUST, a considerably improved acidogenic performance of solid organic wastes was accomplished in terms of VA production, VS degradation, and particle hydrolysis.