Burn injury suppresses human dermal dendritic cell and Langerhans cell function

Human skin contains epidermal Langerhans cells (LCs) and dermal dendritic cells (DCs) that are key players in induction of adaptive immunity upon infection. After major burn injury, suppressed adaptive immunity has been observed in patients. Here we demonstrate that burn injury affects adaptive immunity by altering both epidermal LC and dermal DC functions. We developed a human ex vivo burn injury model to study the function of DCs in thermally injured skin. No differences were observed in the capacity of both LCs and dermal DCs to migrate out of burned skin compared to unburned skin. Similarly, expression levels of co-stimulatory molecules were unaltered. Notably, we observed a strong reduction of T cell activation induced by antigen presenting cell (APC) subsets that migrated from burned skin through soluble burn factors. Further analyses demonstrated that both epidermal LCs and dermal DCs have a decreased T cell stimulatory capacity after burn injury. Restoring the T cell stimulatory capacity of DC subsets might improve tissue regeneration in patients with burn wounds.     

Regulatory networks,genes and glycerophospholipid biosynthesis pathway in schistosomiasis: A systems biology view for pharmacological intervention

Understanding network topology through embracing the global dynamical regulation of genes in an active state space rather than traditional one-gene–one trait approach facilitates the rational drug development process. Schistosomiasis, a neglected tropical disease, has glycerophospholipids as abundant molecules present on its surface. Lack of effective clinical solutions to treat pathogens encourages us to carry out systems-level studies that could contribute to the development of an effective therapy. Development of a strategy for identifying drug targets by combined genome-scale metabolic network and essentiality analyses through in silico approaches provides tantalizing opportunity to investigate the role of protein/substrate metabolism. A genome-scale metabolic network model reconstruction represents choline–phosphate cytidyltransferase as the rate limiting enzyme and regulates the rate of phosphatidylcholine (PC) biosynthesis. The uptake of choline was regulated by choline concentration, promoting the regulation of phosphocholine synthesis. In Schistosoma, the change in developmental stage could result from the availability of choline, hampering its developmental cycle. There are no structural reports for this protein. In order to inhibit the activity of choline–phosphate cytidyltransferase (CCT), it was modeled by homology modeling using 1COZ as the template from Bacillus subtilis. The transition-state stabilization and catalytic residues were mapped as ‘HXGH’ and ‘RTEGISTT’ motif. CCT catalyzes the formation of CDP-choline from phosphocholine in which nucleotidyltransferase adds CTP to phosphocholine. The presence of phosphocholine permits the parasite to survive in an immunologically hostile environment. This feature endeavors development of an inhibitor specific for cytidyltransferase in Schistosoma. Flavonolignans were used to inhibit this activity in which hydnowightin showed the highest affinity as compared to miltefosine.     

α-Tocopheryl succinate pre-treatment attenuates quinone toxicity in prostate cancer PC3 cells

α-Tocopheryl succinate is one of the most effective analogues of vitamin E for inhibiting cell proliferation and inducing cell death in a variety of cancerous cell lines while sparing normal cells or tissues. αTocopheryl succinate inhibits oxidative phosphorylation at the level of mitochondrial complexes I and II, thus enhancing reactive oxygen species generation which, in turn, induces the expression of Nrf2-driven antioxidant/detoxifying genes. The cytoprotective role of Nrf2 downstream genes/proteins prompted us to investigate whether and how α-tocopheryl succinate increases resistance of PC3 prostate cancer cells to pro-oxidant damage. A 4 h α-tocopheryl succinate pre-treatment increases glutathione intracellular content, indicating that the vitamin E derivative is capable of training the cells to react to an oxidative insult. We found that α-tocopheryl succinate pre-treatment does not enhance paraquat-/hydroquinone-induced cytotoxicity whereas it exhibits an additional/synergistic effect on H₂O₂-/docetaxel-induced cytotoxicity.     

山丹不同居群花粉形态研究

为掌握山丹居群在孢粉学方面的遗传多样性,在扫描电子显微镜下对25个居群的山丹花粉进行了形态观察,结果表明:山丹花粉粒形态为单花粉粒,极面观为椭圆体,具单萌发沟。不同居群的花粉粒在大小、网眼直径、萌发沟宽、P/E值和外壁纹饰等方面存在不同程度的差异,且居群间花粉性状的变异大于居群内的变异,最大变异系数达25.52%。     

外加电场刺激对菲降解菌的影响

以菲为主要C源,吐温80作为增溶剂,研究细菌Enterobacter dissolvens在直流电和交流电条件下的生长和代谢过程。实验结果表明:当施加10 mA直流电时,通电8 h后,菌液中细胞的菲降解率较对照增长1.6倍,细胞生长亦有所加快;而施加交流电时,细菌生长和菲降解率均低于直流电刺激。     

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。     

Studies on Essential Oil trom Zanthoxylum avicennae, (Lam.) DC. and Its Antimildew Active

By means of rotatory belt fractional distillation, LC, HPLC, PGC and derivative methods, 27 compounds were separated from the essential oil which isolated from Zanthoxylum avicennae (Lam.) DC. by stream distillation. Twenty two of them were identified by the methods of IR, GC/IR,, 1H-NMR,18C-NMR, GC/MS/DS and the preparation of derivatives. Among them, 4-methyl-6-acetoxyhexanal was first found in nature. Fifteen compounds have been tested their antimildew activities. Citral, l-octanol, 4-methyl-6-acetoxyhexanal and linalool showed strong activities. The relationships between the structure of compounds of essential oil and their respective antimildew activities are also dealt with in this paper.     

桔梗一新栽培变种

桔梗一新栽培变种,即重瓣桔梗Plantycodon grandiflorus(Jacq) A.DC.cv.plenus X.S.Wen。     

Functions of pipecolic acid on induced resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000 in tomato plants

Amino acid metabolic pathways are involved in the plant immune system. Pipecolic acid (Pip), a lysine-derived non-protein amino acid, acts as an important regulator of disease resistance. Here, we report the functions of Pip on tomato disease resistance. Tomato seedlings treated with 0.5 mM Pip showed increased resistance to Pst DC3000 and B. cinerea compared with the control. After pathogen infection, the expression of defence-related genes increased in plants pretreated with Pip, while reactive oxygen species (ROS) accumulation decreased. These data demonstrated that exogenous application of Pip induced resistance against Pst DC3000 and B. cinerea in tomatoes, possibly through the regulation of ROS accumulation and defence-related gene expression.     

Chemical constituents from Bupleurum chinese and their chemotaxonomic significance

A phytochemical investigation of the roots of Bupleurum chinese DC. led to the isolation of eighteen compounds, including three chromones (1–3), seven flavonoids (4–10), one dihydrochalcone (11), two phenylpropanoid glycosides (12–13), one lignan (14), three sterols (15–17) and one stilbenoid (18). Their structures were elucidated on the basis of NMR spectroscopic analysis and comparison with literature data. Compounds 6–7, 11–14 and 18 were firstly reported from the genus Bupleurum and the family Apiaceae. Moreover, the chemotaxonomic value of the isolates was also discussed.