Outbreak of anaplasmosis associated with novel genetic variants of Anaplasma marginale in a dairy cattle

During early lactation, dairy cows may present a transient immunosuppressive state and develop anaplasmosis caused by Anaplasma marginale. In this study, clinical anaplasmosis in dairy cattle in the Thrace region of Turkey was investigated with respect to within-herd prevalence, vertical transmission, and genetic diversity. In March and September 2015, thirty lactating cows showed primary clinical signs of anaplasmosis, including fever, anaemia, decreased milk yield, anorexia, and laboured breathing. Symptoms disappeared in most cows after administration of long-acting oxytetracycline, but nine of them (30%) died. Following diagnosis based on clinical signs, microscopy and molecular findings, blood samples were collected from apparently healthy lactating cows (n = 184), pregnant heifers (n = 39) and newborn calves (n = 24). DNA was extracted from each sample and analyzed for the presence of major surface proteins (MSPs) of A. marginale, followed by sequencing to assess diversity of isolates. Microscopic examination of erythrocytes revealed A. marginale inclusion bodies in symptomatic cows. Examination of thin blood smears showed 3.8% of the lactating, clinically asymptomatic, cows to be infected with A. marginale, while nPCR detected 31.0% positive. A. marginale infection was not detected in pregnant heifers by either method. Congenital infection was found in one calf by nPCR. This is the first report of transplacental transmission of A. marginale in Turkey. The MSP4 sequence analyses showed high genetic diversity among the isolates, presenting 97.6-99.6% homology at the amino acid level. The sequences of MSP1a amplicons revealed genetic diversity providing three new tandem repeats.     

嵌套子集:引入土壤多样性研究的讨论

嵌套子集指在任何特定集合中出现的物种趋向于在更大的集合中也出现,即局部丰富的物种一般分布比较广泛,而局部稀少的物种则分布较窄。本文对嵌套性研究中的有关问题做一评述,并以西班牙的一个研究为范例讨论可以看出,通过数据(土壤类型和土壤集合)试验得出的规律性和生态学上的观点竟非常相似。研究采用了土壤数据集和在计量生态学应用的方法,包括嵌套计算程序(Nested Calcu lator Program)。结果表明:嵌套性在生物群落、土被或土链结构中的性质有相似之处,即地学系统中普遍存在着嵌套性。此方法用于土壤多样性的分析,在有计划的保护生物及土壤资源方面具有现实意义。     

基于嵌套子集方法对南京市城镇化用地时空变化分析

随着城镇化的加速发展,越来越多的土地资源被占用。本文应用嵌套子集方法,并借助RS和GIS技术,利用1984、1995、2000、2003年4期TM卫星遥感影像,对南京市近20年来城镇扩展情况进行了分析。结果表明:1984─2003年间,随着城市化水平的不断提高,南京市城镇用地面积不断扩大,填充度从1984年的3.5%提高到2003年的7.2%,增加1倍多,并呈嵌套格局,且嵌套程度越来越高;各乡镇填充度的变化表现出差异性,即市区的乡镇、市区周边的乡镇以及在区县的乡镇的填充度增加较大,其他大部分乡镇的填充度虽然都有不同程度的增加,但增加程度不大,还有一些乡镇的填充度没有变化。     

蜂胶类黄酮对糖尿病合并肺结核患者外周血WBC与T淋巴细胞亚群的影响

目的 探讨蜂胶类黄酮对糖尿病合并肺结核（diabetes mellitus complicated with pulmonary tuberculosis,DM-PTB）患者外周血中WBC与T淋巴细胞亚群的影响。方法 以DM-PTB患者120人为对象,利用随机数字表采用完全随机法分成A（蜂胶黄酮1 000 mg/d）、B（蜂胶黄酮2 000 mg/d）、C（条件对照）三组,每组40人,观察6个月,比较综合治疗前后白细胞计数（WBC）及分类（淋巴细胞L和中性粒细胞N）、T淋巴细胞亚群CD3⁺、CD4⁺、CD8⁺数量及CD4⁺/CD8⁺比值的变化,并比较组内前后差异和组间差异。结果 三组7项观测指标自身前后配对差值（治疗后-治疗前）的均数比较Hotelling T²=515.359,P=0.000;治疗7项观测指标差别Wilks λ=0.017,P=0.000,其中多重比较结果为WBC的B组大于A与C组,L的B组> A组> C组,N的B组大于A与C组,CD3⁺的B 与A组大于C组,CD4⁺的B组>A组>C组,CD4⁺/CD8⁺比值多重比较结果为B 与A组大于C组。结论 蜂胶类黄酮能提高DM-PTB患者的细胞免疫水平。     

板蓝根多糖对缺乳仔鼠免疫器官发育及T淋巴细胞亚群的影响

试验应用流式细胞术检测缺乳仔鼠CD3⁺、CD4⁺和CD8⁺ T淋巴细胞含量来研究添加不同剂量的板蓝根多糖(RIP)对缺乳仔鼠免疫器官及T淋巴细胞亚群的影响。结果表明:①RIP可增加缺乳仔鼠胸腺指数和脾脏指数。对胸腺指数和脾脏指数效果最好的RIP剂量随日龄增大而减小。②RIP可以增加缺乳仔鼠外周血CD3⁺、 CD4⁺ 、CD8⁺ T淋巴细胞数量。7~28日龄时初乳组(A组)、缺乳+中RIP组(C组)和缺乳+高RIP组(D组)3组CD3⁺ T淋巴细胞含量与缺乳组(B组)相比差异显著(P<0.05)。7~21日龄时初乳组(A组)、缺乳+中RIP组(C组)和缺乳+高RIP组(D组)3组CD4⁺ T淋巴细胞含量与缺乳组(B组)相比差异显著(P<0.05)。各处理组CD3⁺、 CD4⁺、CD8⁺ T淋巴细胞含量及CD4⁺/CD8⁺比值随着日龄的增加有所下降。适宜剂量的RIP可促进缺乳仔鼠免疫器官发育,提高T淋巴细胞亚群的水平。     

基于巢式PCR的重叠延伸PCR优化

[目的]结合巢式PCR对重叠延伸PCR进行优化。[方法]以褐飞虱Actin 1基因启动子区与EGFP表达盒区基因融合为例,通过巢式PCR对重叠延伸PCR进行优化。[结果]成功获得融合片段,经过巢式PCR优化后大大简化试验流程,缩短试验时间,并增强PCR特异性与检出率。[结论]优化了重叠延伸PCR,可更快速高效融合基因片段。     

基于牡蛎疱疹病毒DNA聚合酶基因的巢式PCR检测方法的建立及应用

为了建立适用于Os HV-1不同变异株的检测方法,在牡蛎疱疹病毒(Os HV-1)3个变异株全基因组序列比对的基础上,筛选到牡蛎疱疹病毒基因组中高度保守的DNA聚合酶(DNA polymerase)基因,据此设计巢式PCR引物,优化PCR反应体系和条件,建立了基于Os HV-1 DNA聚合酶基因的巢氏PCR检测方法(P-n PCR检测方法),利用P-n PCR与Cn PCR检测方法对不同年份和宿主来源的Os HV-1疑似感染样本进行检测。结果显示,Pn PCR检测方法能稳定地检出100拷贝/μL的病毒DNA;P-n PCR较C-n PCR检测方法具有更强的特异性和更高的检出率。研究表明,本研究建立的P-n PCR检测方法适用于Os HV-1不同变异株的检测,可为该病毒的检测和流行病学调查提供可靠的技术支持。     

Core subsets of base collections and priorities of national programmes: Indian perspective

Summary The establishment of representative core collections and back-up reserve collections was proposed to facilitate effective management and to promote utilization of large base collections. The priorities of the developing national PGR programmes, in the organization of components of their base collections, are different from those of IARCs since the strengths as well as limitations of the two systems vary. Unlike most IARCs, national programmes have the option of networking their active collections, maintained at several eco-sites, and linking this network to the base collection kept under long-term storage. This keeps open the option to develop situation-specific subsets for an effective germplasm utilization. There is a pressing need for a scientific re-examination of the concept of germplasm core in order better to apply it in developing core subsets in the national PGR programmes. The formulation of situation-specific subsets is advocated, as the system would be directed to users' requirements or addressed to gene bank managers' resource constraints. Arguments given in favour of developing core subsets, rather than a single core are: (i) logical; (ii) population genetic; and (iii) germplasm usage considerations. The Indian PGR programme and the emerging core context are briefly discussed, along with features of a programme designed to develop such core subsets.Abbreviations IARCs = International Agriculture Research Centers - NBPGR = National Bureau of Plant Genetic Resources - NAGS = National Active Germplasm Collection Site - NGSNs = National Germplasm Screening Nurseries - GACs = Germplasm Advisory Committees     

作物生育指标空间变异性套合结构模型的建立

本文通过田间系统采样，运用地质统计学原理探讨了株高、茎粗两生育指标的空间结构性，并建立了东西、南北、东北、西北四个方向的变差函数模型。结果显示两变量具有较明显的区域化变量特征和较好的空间结构性。且变差函数模型为带状异向性。运用模型迭加的方法建立了所研究变量的带状各向异性套合结构模型。