外源激素组合控制青春期前奶山羊卵泡超数同步发育及其卵母细胞发育潜能的评价

本研究的目的是探索自青春期前奶山羊获取大量可用于体细胞核移植的卵母细胞的可能性。为此,本研究比较了几种不同组合的激素处理方法(对照、FSH、E2-P4和E2-P4-FSH)对出生39-60日龄的奶山羊卵巢大小、卵泡数量和卵泡大小的影响:同时将出生39-120日龄奶山羊按年龄分成三组来研究年龄对激素处理时招募起始生长卵泡数量的影响:然后,比较了来自E2-P4- FSH和FSH处理的早青春期前奶山羊卵巢上直径大于3mm卵泡中卵母细胞减数分裂能力;最后,通过SCNT方法验证E2-P4-FSH处理的早青春期前奶山羊卵巢上直径大于3mm卵泡中卵母细胞的发育能力。在四组激素处理的早青春期前奶山羊中,E2-P4-FSH处理组的卵巢最大、卵泡(直径大于3 mm)数量最多。在不同的年龄组中,39-60天组奶山羊卵巢上直径大于3mm的卵泡数量显著多于61-90天和91-120天组的。卵母细胞减数分裂能力的分析结果表明,来自E2-P4-FSH处理组的卵母细胞减数分裂能力显著高于FSH处理组的卵母细胞。与E2-P4-FSH处理后的成年奶山羊卵母细胞相比,早青春期前奶山羊卵母细胞发育能力较低:卵母细胞成熟后,作为受体用于体细胞核移植后的克隆囊胚发育率低于成年奶山羊(15.3%versus 22.1%,P<0.01)。然而,早青春期前的奶山羊经E2-P4-FSH处理后,自每头羊卵巢上直径大于3mm的卵泡数显著高于成年奶山羊(108±10.3 versus 28±5.0),因此,每头早青春期前奶山羊产生的克隆囊胚绝对数量显著高于成年奶山羊(7.1±2.7 versus 4.2±1.4)。由此,从本研究可以得出结论:E2-P4-FSH处理的早青春期前奶山羊能够为体细胞核移植研究提供相对多数量的具备一定发育能力的成熟卵。     

Structure Studies of the CRISPR-Csm Complex Reveal Mechanism of Co-transcriptional Interference

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利用复感儿T淋巴细胞作为外源性ADA基因表达效应细胞的实验探讨

对４１例健康儿童和１７例反复呼吸道感染患儿（复咸儿）的外周血淋巴细胞ＡＤＡ活性进行了检测．两例ＡＤＡ活性明显低下的复感儿的外周血Ｔ淋巴细胞被选作实验样品,经体外培养后,采用ｌｉｐｏｆｅｃｔｉｎ介导的的方法导入外源性ＡＤＡ基因．结果表明：体外培养的两例复感儿淋巴细胞中ＡＤＡ活性较基因转移前升高;细胞免疫学特性也在一定程度上获得改善     

间接FLISA法检测钩端螺旋体特异性IgM方法的探讨

为研制钩端螺旋体（钩体）特异性IgM检测试剂,并用于早期诊断钩体病,以钩体外膜蛋白为抗原,探索间接ELISA法检测钩体特异性IgM的各项实验条件,并对钩体病患者血清标本进行检测,结果,１０５份健康人血ＩgM阴性,钩体IgM阳性血清可被特异性阻断,２－巯基乙醇破坏试验阳性,试剂存放４℃和３７℃4天的检测结果基本一致,检测临床钩体病人112份血清,IgM阳性83份,阳性率74．11％,与常规TAT法基本一致,0－7病日的阳性率明显高于MAT法,说明该法检测钩体病IgM具有特异,敏感,快速,稳定,简便等优点,对钩体病早期诊断有一定的价值。     

鸡公山遗址发掘初步报告

本文是湖北荆州鸡公山遗址1992年发掘资料的初步研究报告。该遗址分上、下两个文化层。下文化层出土数量较多的小石片石器,时代约为晚更新世晚期,下文化层含数以万计的砾石石器,时代可能处于中晚更新世之交或稍早。尤为重要的是下文化层近500m^2活动面的发展,显示早期人类曾较长时间占用该遗址并从事多种活动。     

Investigation of transferability of BovineSNP50 BeadChip from cattle to water buffalo for genome wide association study

Cattle and water buffalo belong to the same subfamily Bovinae and share chromosome banding and gene order homology. In this study, we used genome-wide Illumina BovineSNP50 BeadChip to analyze 91 DNA samples from three breeds of water buffalo (Nili-Ravi, Murrah and their crossbred with local GuangXi buffalos in China), to demonstrate the genetic divergence between cattle and water buffalo through a large single nucleotide polymorphism (SNP) transferability study at the whole genome level, and performed association analysis of functional traits in water buffalo as well. A total of 40,766 (75.5 %) bovine SNPs were found in the water buffalo genome, but 49,936 (92.5 %) were with only one allele, and finally 935 were identified to be polymorphic and useful for association analysis in water buffalo. Therefore, the genome sequences of water buffalo and cattle shared a high level of homology but the polymorphic status of the bovine SNPs varied between these two species. The different patterns of mutations between species may associate with their phenotypic divergence due to genome evolution. Among 935 bovine SNPs, we identified a total of 9 and 7 SNPs significantly associated to fertility and milk production traits in water buffalo, respectively. However, more works in larger sample size are needed in future to verify these candidate SNPs for water buffalo.     

The crosstalk between autophagic and endo-/exosomal pathways in antigen processing for MHC presentation in anticancer T cell immune responses

T cells recognize antigen fragments from proteolytic products that are presented to them in the form of peptides on major histocompatibility complex (MHC) molecules, which is crucial for the T cell to identify infected or transformed cells. Autophagy, a process that delivers cytoplasmic constituents for lysosomal degradation, has been observed to provide a substantial source of intra- and extracellular antigens for MHC presentation to T cells, which will impact the tumor-specific immune response. Meanwhile, extracellular components are transported to cytoplasm for the degradation/secretion process by the endo-/exosomal pathway and are thus involved in multiple physiological and pathological processes, including immune responses. Autophagy and endo-/exosomal pathways are intertwined in a highly intricate manner and both are closely involved in antigen processing for MHC presentation; thus, we propose that they may coordinate in antigen processing and presentation in anticancer T cell immune responses. In this article, we discuss the molecular and functional crosstalk between autophagy and endo-/exosomal pathways and their contributions to antigen processing for MHC presentation in anticancer T cell immune responses.     

Demyelination Occurred as the Secondary Damage Following Diffuse Axonal Loss in a Rat Model of Radiation Myelopathy

The main purpose of the present study was to examine the time and dose-dependent course of demyelination in the rat radiation myelopathy model in the first 180 days after irradiation of the spinal cord. An irradiated cervical spinal cord rat model (C2-T2 segment) was generated using a ⁶⁰Co irradiator to deliver 50 Gy and 100 Gy, respectively. The behavioral dysfunction was observed by the forelimb paralysis scoring system. The histological damage in the irradiated spinal cord was examined by hematoxylin/eosin staining, luxol fast blue staining, immunohistochemical analysis, methylene blue/Azure II staining, and uranyl/lead salts staining. The gene expression of oligodendrocyte-related markers were also determined by quantitative real-time PCR. The complete loss of forelimb motor function in all animals was observed at 180 days 50 Gy post-irradiation and at 120 days 100 Gy post-irradiation. We demonstrated that a 50 and 100-Gy single-dose irradiation of the C2-T2 spinal cord segment resulted in diffuse axonal loss and elicited secondary demyelination damage in the spinal cord. We further observed that 100-Gy irradiation reduced the gene expression of myelin oligodendrocyte glycoprotein in irradiated spinal cord. Taken together, our data not only define diffuse axonal loss as the main histological damage but also provide the first evidence that demyelination occurred as the secondary damage in irradiated spinal cord.     

A new fossil bird from the Early Cretaceous of Gansu Province,northwestern China

We report on the discovery of an Early Cretaceous bird from northwestern Gansu Province, in northwestern China. Represented by a nearly complete left wing and shoulder girdle the size of a rock dove, the new bird was quarried from laminated yellowish mudstones of the Xiagou Formation (Xinminpu Group) near Changma, in the Jiuquan area. These deposits have previously yielded the only known specimen of Gansus yumenensis, a basal ornithuromorph represented by the distal half of a hind limb with long and slender digits. Several derived characters of the new occurrence supports its allocation within Enantiornithes: (1) a convex lateral margin of the coracoid, (2) a minor metacarpal that projects distally more than the major metacarpal and (3) a proximal phalanx of the major digit longer than the intermediate (second) phalanx. The general proportions of the wing suggest it was a flier comparable to most other known enantiornithine birds. Although, direct comparisons between the new fossil and Gansus are not possible, phylogenetic based inferences supports their placement into two different clades. While the new fossil falls definitively within the enantiornithines, G. Yumenensis falls within the ornithuromorphs. The new occurrence thus adds to the taxonomic diversity of Early Cretaceous birds from Gansu Province in particular and central Asia in general.     

Intracellular localization of the p35 subunit of murine IL-12

Production of interleukin-12 (IL-12), a heterodimer of p35 and p40 subunits, is limited by p35 expression. A long and a short murine p35 mRNA potentially encoding proteins differing in pre-sequence size are produced. Increased pre-sequence size could convert a cleaved signal peptide to an uncleaved signal peptide, raising the possibility that a membrane-bound form of p35 is produced. The intracellular localization of the p35 encoded by each mRNA isoform was determined by constructing cDNAs containing the long or short p35 cDNA isoform fused in-frame to a cDNA encoding green fluorescent protein (GFP). After transfection of a CV-1 African green monkey kidney cell line with the constructs, confocal microscopy and immunoblotting of extracted microsomal membranes demonstrated that the p35-GFP fusion protein encoded by the long or short mRNA accumulates in the Golgi apparatus as an endoglycosidase H-sensitive glycosylated integral membrane protein. In contrast, a p40-GFP fusion protein accumulates in the Golgi apparatus as a soluble protein. Since assembly of the p35 and p40 subunits to form bioactive IL-12 occurs in the ER, release of membrane-tethered IL-12 by proteolytic cleavage in a late Golgi or post-Golgi compartment may represent an as yet unidentified level at which bioactive IL-12 secretion is regulated.