Altered Plasma Concentrations of Trace Elements in Ulcerative Colitis Patients Before and After Surgery

Ileal pouch-anal anastomosis (IPAA) is a classical surgery for ulcerative colitis patients. However, knowledge on trace element alteration in patients who had undergone this surgery is limited. This study was conducted to assess trace element alteration in patients with ulcerative colitis before and after ileal pouch-anal anastomosis. Preoperative (40) and postoperative (35) ulcerative colitis patients were studied. The dietary assessment of trace element intake was undertaken by a semiquantitative food frequency questionnaire. Patients' trace element status of zinc, copper, manganese, selenium, calcium, iron, and vitamin D₃ was assessed by measuring their blood concentrations. We found that with the similar dietary intake, there was no statistical difference in the concentrations of plasma copper, iron, calcium, and vitamin D₃ in the two groups (P?>?0.05). Compared with preoperative patients, postoperative patients had higher concentrations of plasma zinc (14.51?±?4.75 μmol/l) and manganese (0.21?±?0.11 μmol/l) and lower concentrations of plasma selenium (0.86?±?0.58 μmol/l). Both preoperative and postoperative mean concentrations of plasma calcium and vitamin D₃ were below their reference range, respectively. We conclude that IPAA does not seem to alter patients' abnormal trace elements completely. It is important to monitor and supply some specified trace elements even in postoperative patients.     

Phospholipase A2-like activity of human bocavirus VP1 unique region

Human bocavirus (HBoV) is a new parvovirus first discovered in 2005, which is associated with acute respiratory infection. Analysis of sequence homology has revealed that a putative phospholipase A₂ (PLA₂) motif exists in the VP1 unique region of HBoV. However, little is known about whether the VP1 unique region of HBoV has PLA₂ enzymatic activity and how these critical residues contribute to its PLA₂ activity. To address these issues, the VP1 unique region protein and four of its mutants, were expressed in Eschericha coli. The purified VP1 unique protein (VP1U) showed a typical Ca²⁺-dependent secreted PLA₂-like (sPLA₂) activity, which was inhibited by sPLA₂-specific inhibitors in a time-dependent manner. Mutation of one of the amino acids (21Pro, 41His, 42Asp or 63Asp) in VP1U almost eliminated the sPLA₂ activity of HBoV VP1U. These data indicate that VP1U of HBoV has sPLA₂-like enzymatic activity, and these residues are crucial for its sPLA₂-like activity. Potentially, VP1U may be a target for the development of anti-viral drugs for HBoV.     

Genetic and alkaloid analysis of Menispermum dauricum DC. by RAPD and HPLC

The aim of the present work was to determine whether dauricine could be used as a taxonomic marker for Menispermum dauricum DC., and to explore the correlation among RAPD, ecological markers and chemical markers. To this end, the chemical and genetic differences of 173 individual samples of M. dauricum from nine different sources were studied based on the relevant ecological factors including longitude, latitude, annual precipitation, mean temperature, annual accumulated temperature and mean sea level. The contents of dauricine in the sample rhizomes were assayed by HPLC with photodiode array detection. The leaves from the same sample were assayed using randomly amplified polymorphism DNA (RAPD). The genetic distances were then compared. Hierarchical cluster analysis and multiple linear stepwise regression analysis were used in the statistical analysis. The results indicated that the contents of dauricine were respectively correlated with the genetic distance (r = 1.000), longitude (r = 0.849), latitude (r = 0.861), annual precipitation (r = 0.903), mean temperature(r = 0.912), annual accumulated temperature (r = 0.919) and mean sea level (r = 0.925). It is concluded that the content of dauricine in M. dauricum is significantly correlated with genetic distance and ecological factors, and may be used as the taxonomic marker.     

红凤菜新鲜茎叶中总黄酮提取物的LC-MS分析

红凤菜（Gynura bicolor DC.）为菊科（Compositae）菊三七属（Gynura Cass.）植物,别名血皮菜、观音菜、观音苋、紫背天葵等,主要分布于中国南方各地,全草均可入药[1];也可作为蔬菜食用,在国内多个地区均有栽培和销售。目前已知红凤菜含有黄酮类、酚性酸类、萜类、甾醇类、脂肪酸类、生物碱类及花青素类等[2-7]成分。由于黄酮类成分多具有保护心血管、抗肿瘤、抗糖尿病、抗氧化、抗炎和抗病毒等作用[8],因此对红凤菜中黄酮类成分的研究具有深度开发价值。     

Biological control of oilseed rape Sclerotinia stem rot by Bacillus subtilis strain Em7

In the present study, the endophytic bacterium Bacillus subtilis strain Em7 (GU258545.1) was evaluated as a biological control agent for Sclerotinia sclerotiorum on oilseed rape. In petri dish, strain Em7 not only strongly inhibited pathogen mycelium growth but also germination of sclerotia at concentrations between 10⁹ and 10¹¹ colony forming unit (CFU)·ml^?1. Scanning electron microscopy and transmission electron microscopy studies revealed that in the presence of strain Em7, hyphae of S. sclerotiorum showed leakage and disintegration of hyphal cytoplasm. Furthermore, the strain Em7 showed a broad antifungal spectrum on mycelium growth of numerous important plant pathogenic fungi. Light microscopic observations revealed that strain Em7 caused morphological alterations including increased branching, swelling and collapse of cytoplasm. In the greenhouse, spray treatments of cell suspensions of strain Em7 (1×10⁹ CFU·ml^?1) reduced leaf and stem rot incidence and severity in the seedling and blossom stage. The control efficacy was higher when strain Em7 cell suspension was applied one day prior to inoculation of the pathogen than after inoculation. Three-year field trials showed that two applications of strain Em7 cell suspension at blossom stage significantly reduced disease incidence and severity by 50–70%. There was no significant difference in control efficacy among treatments with strain Em7 cell suspension and the fungicides containing carbendazim or tebuconazole (P = 0.05). Thus, our results strongly suggest that B. subtilis strain Em7 is a promising biological control agent for control of oilseed rape Sclerotinia stem rot.     

Disruption of YPS1 and PEP4 genes reduces proteolytic degradation of secreted HSA/PTH in Pichia pastoris GS115

Human serum albumin (HSA) and human parathyroid hormone (1-34) [PTH (1-34)] fusion protein [HSA/PTH (1-34)] is a promising long-acting form of PTH (1-34) for osteoporosis treatment. Secretory expression of intact HSA/PTH (1-34) in Pichia pastoris GS115 was accompanied by two degradation fragments, with molecular weights around 66 kDa, in addition to the well-known ~45 kDa HSA-truncated fragment, resulting in a low yield of intact protein. In this study, two internal cleavage sites were identified in the PTH (1-34) portion of the fusion protein by Western Blot analysis. To minimize proteolytic cleavages, several protease genes including PEP4 (encoding proteinase A), PRB1 (proteinase B) and seven YPSs genes (yapsin family members) were knocked out respectively by disruption of the individual genes and the selective combinations. Reduced degradation was observed by single disruption of either PEP4 gene or YPS1 gene, and the lowest level of degradation was observed in a pep4△yps1△ double disruptant. After 72 h of induction, more than 80 % of the HSA/PTH (1-34) secreted by the pep4△yps1△ double disruptant remained intact, in comparison to only 30 % with the wild-type strain.     

西南干旱河谷植物多样性资源的保护与利用

西南干旱河谷是分布于我国亚热带横断山区的隐域性河谷景观, 其环境受季风气候、岭-谷地形环境和人类开发活动的共同影响。适应于季节性干旱和垂直气候分异, 干旱河谷具有独特的植被和丰富的物种多样性资源。在过去几十年中, 干旱河谷的气候变化以增温为一致特征, 同时经历着广泛的人类活动干扰, 特别是道路建设、水利工程、矿山开发和城镇化驱动的土地利用变化, 造成了普遍的植被破坏、生境退化和生物入侵, 给乡土植物多样性资源和生态系统稳定性带来了严重威胁, 然而至今对干旱河谷生物多样性的保护仍基本属于空白。因此, 建议及时建立干旱河谷的生物多样性保护体系; 因地制宜采取退化植被修复、立体农业规划、特色植物资源利用和风景旅游开发等措施, 以维持干旱河谷生态系统的可持续性; 落实生态文明建设的相关政策, 以保障西南生态屏障的生态安全和生态服务能力。     

种子老化诱导小麦染色体畸变及大麦醇溶蛋白带型频率变化的研究

通过时20份小麦种质发芽率和根尖细胞染色体畸变的测定,结果表明同一品种贮藏于中期库的低发芽率种质,其染色体畸变率明显高于贮藏于长期库的高发芽率种质.从总体上看,种子根尖细胞染色体畸变率与发芽率呈负显著相关,而与贮藏年限无显著相关.但对长期库和中期库的种质分别进行统计分析,种子根尖染色体畸变率与发芽率和贮藏年限均无显著相关.对大麦地方品种"普乃干木"的醇溶蛋白分析表明,该品种有4种biotype,随着发芽率的下降,其群体中的4种bio-type的频率发生了变化,当发芽率从95%降到34%时,其中一种biotype出现了消失,而有一种biotype频率从83%上升至95%,此结果表明,种子生活力下降和不同biotype种子存活能力存在差异,可能导致了异质种质材料遗传选择和漂变的发生.