In vitro neuronal and osteogenic differentiation of mesenchymal stem cells from human umbilical cord blood

Mesenchymal stem cells (MSCs) have the capabilities for self-renewal and differentiation into cells with the phenotypes of bone, cartilage, neurons and fat cells. These features of MSCs have attracted the attention of investigators for using MSCs for cell-based therapies to treat several human diseases. Because bone marrow-derived cells, which are a main source of MSCs, are not always acceptable due to a significant drop in their cell number and proliferative/differentiation capacity with age, human umbilical cord blood (UCB) cells are good substitutes for BMCs due to the immaturity of newborn cells. Although the isolation of hematopoietic stem cells from UCB has been well established, the isolation and characterization of MSCs from UCB still need to be established and evaluated. In this study, we isolated and characterized MSCs. UCB-derived mononuclear cells, which gave rise to adherent cells, exhibited either an osteoclast or a mesenchymal-like phenotype. The attached cells with mesenchymal phenotypes displayed fibroblast-like morphologies, and they expressed mesenchym-related antigens (SH2 and vimentin) and periodic acid Schiff activity. Also, UCB-derived MSCs were able to transdifferentiate into bone and 2 types of neuronal cells, in vitro. Therefore, it is suggested that the MSCs from UCB might be a good alternative to bone marrow cells for transplantation or cell therapy.     

蚕粪中提取叶绿素铜钠盐的稳定性研究

以蚕粪为原料,95%的乙醇为溶剂提取叶绿素,并通过化学法制得叶绿素的铜纳盐。采用721分光光度计对叶绿素铜钠盐进行定性、定量测定,确定该色素测定系统中的最大波长为414nm。通过测量吸光值研究了几种常用食品添加剂对叶绿素铜钠盐稳定性的影响,并对其耐光、耐热、耐酸碱及耐氧化性、耐还原性进行探讨。结果表明:叶绿素铜钠盐在70℃以下稳定性较好;光照对叶绿素铜钠盐稳定性的影响较大;还原剂(Na2S2O3)对叶绿素铜钠盐稳定性的影响较大,氧化剂在短时间内对其稳定性的影响不大,但放置的时间不宜超过30min;叶绿素铜钠盐在pH值为6以上的溶液中较为稳定,且有机酸及单糖对其稳定性无明显影响。     

浙江省缙云县农机服务专业合作社发展现状与对策

为发挥农机服务专业合作社在浙江省缙云县农业生产中的作用,归纳总结了缙云县农机服务专业合作社发展的现状和成效,并对该县当前农机服务专业合作社发展存在的问题进行了分析,在此基础上提出了加快发展缙云县农机服务专业合作社的相关措施建议。      

青霉酸毒性研究进展

青霉酸是圆弧青霉代谢产物的主要成分。现已证明,青霉酸对各种动物具有毒性,主要引起心脏、肝脏和肾脏等器官的损伤,并具有潜在致癌性。青霉酸在饲料中的含量很高,而且污染极其广泛。因此,研究青霉酸的毒性、中毒机理及与其他毒素的联合作用,对保证饲料卫生和动物健康具有很重要的意义,该文就青霉酸的器官毒性、细胞毒性、分子毒性及联合毒性的研究进行综述。     

SHORT COMMUNICATION: Normal aerobic bacterial conjunctival flora in the Crab‐eating raccoon (Procyon cancrivorus) and Coati (Nasua nasua) housed in captivity in pernambuco and paraiba (Northeast,Brazil)

Objective To determine the normal aerobic bacterial conjunctival population of the Coatis and the Crab‐eating raccoons housed in captivity in the Pernambuco and Paraiba states of Brazil. Animals studied Ten healthy Coatis and 10 healthy Crab‐eating raccoons were selected for this study. Animals are from three zoos situated at the Pernambuco and Paraiba States in the north‐east of Brazil. Procedures After ophthalmologic examination, swabs from healthy animals were carefully collected in order to avoid contamination. Samples were identified and submitted to the laboratory. Swabs were plated for culture on ovine blood agar (8%) and agar Levine and incubated at 37 °C and observed 24 and 48 h. Results Staphylococcus spp. was the most common microorganism isolated from conjunctival sac. Shigella spp. comprised the Gram‐negative genera isolated. Escherichia coli were isolated from the right eye of one Coati that had no growth at contralateral eye. Nine eyes from coatis and 10 from Crab‐eating raccoons had no microorganisms isolated. Conclusion Our results were in accordance with previous studies indicating Staphylococcus sp., followed by Corynebacterium spp. as the most common inhabitant of the eyes of most mammalian species.     

Selection and Evaluation of Indexes Commonly Used to Determine Contamination with T-2 Toxin in Pacific White Shrimp Litopenaeus vannamei by the Grey Relational Method

Abstract

The objectives of the present study were to evaluate the effects of different concentrations of the mycotoxin T-2 toxin in feed on muscle performance in the Pacific white shrimp Litopenaeus vannamei, evaluate indexes of physiological variables that indicate T-2 toxin contamination in the shrimp using the grey relational method, and determine the dose–response relationships between T-2 toxin and the indexes. Of the 6 physical, 7 biochemical, and 17 nutritional indexes examined, the values of the grey relational coefficients were highest for the hepatopancreas: body weight ratio (HBR), alanine aminotransferase (ALT) activity, and serine (SER) content (0.83, 0.68, and 0.82, respectively). Therefore, the HBR, ALT activity, and SER content were selected as appropriate indexes for contamination of Pacific white shrimp muscle with T-2 toxin. Based on their dose–response relationship curves, mean effective doses of 1.45, 1.69, and 1.33 mg of T-2 toxin/kg of feed were obtained for the HBR, ALT activity, and SER content, respectively. These results offer technical reference points for the evaluation and control of T-2 toxin in shrimp feed.

Received April 28, 2016 accepted April 9, 2017 Published online July 26, 2017     

早春短命植物绵果荠愈伤组织诱导相关因素研究

绵果荠是分布在新疆北部准噶尔荒漠中的十字花科一年生早春短命植物。本研究为探讨绵果荠愈伤组织诱导条件,以无菌苗子叶为外植体,研究了不同苗龄、培养基种类、蔗糖浓度和培养条件对愈伤组织的诱导及其生长的影响。结果表明,1)愈伤组织诱导的最佳条件为:苗龄14 d、培养基为MS+1.0 mg/L IBA+0.1 mg/L BAP、含糖量3%、温度25℃和光照为黑暗。2)愈伤组织生长的适宜条件是光照16 h/d和温度25℃。     

Systematic Review of Brain Tumor Treatment in Dogs

Intracranial neoplasia is commonly diagnosed in dogs and can be treated by a variety of methods, but formal comparisons of treatment efficacy are currently unavailable. This review was undertaken to summarize the current state of knowledge regarding outcome after the treatment of intracranial masses in dogs, with the aim of defining optimal recommendations for owners. This review summarizes data from 794 cases in 22 previously published reports and follows PRISMA guidelines for systematic review. A Pubmed search was used to identify suitable articles. These then were analyzed for quality and interstudy variability of inclusion and exclusion criteria and the outcome data extracted for summary in graphs and tables. There was a high degree of heterogeneity among studies with respect to inclusion and exclusion criteria, definition of survival periods, and cases lost to follow‐up making comparisons among modalities troublesome. There is a need for standardized design and reporting of outcomes of treatment for brain tumors in dogs. The available data do not support lomustine as an effective treatment, but also do not show a clear difference in outcome between radiotherapy and surgery for those cases in which the choice is available.     

鸡β-防御素及其应用前景

防御素是生物界广泛存在的一类具微生物抗性的低分子肽，由于其抗菌谱最广，具有很高的应用潜力。本文概述了鸡β-防御素的分子结构、抗菌活性、基因表达调控的研究进展，并展望了其在畜牧业中的应用前景。