MicroRNA expression in the aging mouse thymus

MicroRNAs (miRNAs) have been implicated in the process of aging in many model organisms, such as Caenorhabditis elegans, and in many organs, such as the mouse lung and human epididymis. However, the role of miRNAs in the thymus tissues of the aging mouse remains unclear. To address this question, we investigated the miRNA expression profiles in the thymuses of 1-, 10- and 19-month-old mice using miRNA array and qRT-PCR assays. A total of 223 mouse miRNAs were screened, and the expression levels of those miRNAs exhibited gradual increases and decreases over the course of thymus aging. Fifty miRNAs in the 10-month-old thymus and 81 miRNAs in the 19-month-old thymus were defined as differentially expressed miRNAs (p < 0.05) in comparison with their levels in the 1-month-old mouse, and approximately one-third of these miRNAs were grouped within 11 miRNA clusters. Each miRNA cluster contained 2 to 5 miRNA genes, and most of the cluster members displayed similar expression patterns, being either increased or decreased. In addition, Ingenuity Pathway Analysis (IPA) software and the IPA database were used to analyze the 12 miRNAs that exhibited significant expression changes, revealing that as many as 15 pathways may be involved. Thus, our current study determined the expression profiles of miRNAs in the mouse thymus during the process of aging. The results suggested that these miRNAs could become meaningful biomarkers for studying thymus aging and that the aging-related alternations in miRNA expression may be involved in the regulation of cell proliferation, apoptosis, development and carcinogenesis/tumorigenesis.     

我国主要类型生态系统结构功能与提高生产力途径研究──KJ85－06项目1991～1995研究进展简介

KJ 85-06项目是“八五”期间由中国科学院资助的最大的生态学研究计划.19个研究所、20个试验站、530余名科技人员参加了该项计划,5年总经费1000万元.研究工作取得了重大进展,迄今已发表论文450余篇、专着3部,尚有大量论文与多部专着将陆续出版.本文简要介绍了有关主要研究进展,并就生态系统优化管理研究和生态过程、人类活动影响联网研究提出了两点主张.     

Skin aging caused by intrinsic or extrinsic processes characterized with functional proteomics

The skin provides protection against environmental stress. However, intrinsic and extrinsic aging causes significant alteration to skin structure and components, which subsequently impairs molecular characteristics and biochemical processes. Here, we have conducted an immunohistological investigation and established the proteome profiles on nude mice skin to verify the specific responses during aging caused by different factors. Our results showed that UVB‐elicited aging results in upregulation of proliferating cell nuclear antigen and strong oxidative damage in DNA, whereas chronological aging abolished epidermal cell growth and increased the expression of caspase‐14, as well as protein carbonylation. Network analysis indicated that the programmed skin aging activated the ubiquitin system and triggered obvious downregulation of 14‐3‐3 sigma, which might accelerate the loss of cell growth capacity. On the other hand, UVB stimulation enhanced inflammation and the risk of skin carcinogenesis. Collectively, functional proteomics could provide large‐scale investigation of the potent proteins and molecules that play important roles in skin subjected to both intrinsic and extrinsic aging.     

两种药物性肝炎诊断评分标准的临床应用分析

目的:比较Maria药物性肝损害(1997年)诊断标准和我国常用诊断标准对药物性肝损害的效价。方法:回顾性分析我院2005年1月至2006年4月期间经肝穿病理诊断为药物性肝损害的54例病例,分别按照上述两个标准评分。评价每一标准的准确性。结果:符合Maria药物性肝损害(1997年)诊断标准的(>10分)有45例,占83%;符合我国常用诊断标准的有39例,占72%。结论:两个诊断标准符合率较高,均可做为药物性肝损害的诊断标准,但仍有部分病例不能准确诊断,需进一步完善。     

猕猴桃品种果实性状特征和主成分分析研究

为深入了解猕猴桃不同品种(系)的果实性状与其倍性的相关性,本研究对国家猕猴桃种质资源圃保存的44个栽培品种(系)进行了果实性状分析,结果表明,44个栽培品种(系)的果实性状具有丰富的遗传多样性并且果实重量、果面毛被、果肉颜色和质地、果实维生素C含量、果实后熟天数和软熟果硬度、果实成熟期等与品种(系)倍性呈显著相关。对相关性状采用主成分分析表明,果实成熟时间、果肉质地、果面毛被和果实后熟天数、果肉颜色是区分品种(系)的主要特征。由于品种(系)的倍性与主要性状特征关联,品种(系)按倍性相对聚类,且二倍体品种(系)群和六倍体品种(系)群间无重叠,而四倍体品种(系)群与相邻的二倍体和六倍体品种(系)群均有一定重叠。     

Vegetation,environmental characteristics and ideas on the maintenance of alvars on the Bruce Peninsula,Canada

Abstract. Despite international recognition that alvar habitats are important reservoirs of biodiversity, they remain little studied in North America. In this paper, the results are reported on an investigation of alvars in the central portion of their known distribution on this continent. 210 plots were distributed among seven sites and were quantitatively sampled for vascular plants, lichens, bryophytes and a suite of environmental variables. Detrended and Canonical Correspondence Analyses and other methods were used to investigate differences among alvars, within alvars and between alvars and adjacent forested habitats. The plant communities and environmental conditions were highly similar among sites in the study region, yet very different from surrounding habitats. There were abrupt changes in vegetation and environmental conditions from alvar to forest, without the presence of transition zones in the vegetation or environmental gradients as the forest was approached. The environmental factors associated with the change from alvar to forest and with variation within alvar habitat were examined. Some alvars in the study were found to contain stunted, slow-growing trees reaching ages of 524 yr. These same sites appear to have remained unburned for several centuries, while other sites likely burned 90 yr ago. The plant communities were very similar between the alvars that lacked a major, biomass-removing disturbance in centuries and alvars that had experienced catastrophic fire relatively recently. Maintenance of the plant communities and open nature of alvars appears site-specific rather than habitat specific.     

过敏性眼表疾病的临床特点及诊治研究

目的:对过敏性眼表疾病的临床特点和相关的诊治方法进行分析探讨.方法:选取100例过敏性眼表疾病的患者,对其相应的临床资料进行回顾性分析、通过对过敏性眼表疾病的病史、症状、体征等临床特点进行统计,进而对诊治方法进行分析探讨.结果:50例患者有过敏性眼病史,90例患者表现为眼痒,89例患者表现有异物感,88例患者表现为结膜充血,76例患者表现有上眼睑结膜乳头,70例患者表现有上眼睑结膜滤泡.45例患者为常年过敏性结膜炎,30例患者为特异性结膜炎,10例患者为巨乳头结膜炎,80例患者为过敏性结膜炎,嗜酸性粒细胞的阳性率为100％.经过治疗后,57例患者得到缓解,7例患者得到明显改善,30例患者病情得到控制,且有9例重症患者在急性期应用了激素治疗,6例患者临床症状无明显改善.结论:过敏性眼表疾病的临床症状表现差异较大,对过敏性眼表疾病患者的临床特点做出准确的判断并给出正确及时的治疗,对过敏性眼表疾病患者的恢复有一定的临床意义.     

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal fluctuations over time. Temporal Lobe Epilepsy (TLE) is the most common type of adult epilepsy and involves multiple brain networks. The default mode network (DMN) is involved in conscious, resting state cognition and is thought to be affected in TLE where seizures cause impairment of consciousness. The DMN in epilepsy was examined using seed based fcMRI. The anterior and posterior hubs of the DMN were used as seeds in this analysis. The results show a disconnection between the anterior and posterior hubs of the DMN in TLE during the basal state. In addition, increased DMN connectivity to other brain regions in left TLE along with decreased connectivity in right TLE is revealed. The analysis demonstrates how seed-based fcMRI can be used to probe cerebral networks in brain disorders such as TLE.     

大鳄龟感染蛙病毒的PCR检测及组织病理分析

2013年3月成都市某海洋馆送检2只发病大鳄龟(Macrochelys temminckii),临床特征表现为:精神状态萎靡,爬行无力,对外界刺激反应迟钝;颈部和四肢局部红肿,腹甲溃烂,严重部位甚至穿孔,最后死亡。为明确患病大鳄龟的病因,进行了细菌学、组织病理学和PCR检查。细菌学检查阴性;病理组织学观察发现,大鳄龟多组织、器官均发生严重病变,尤其是肾、肝、肺和心的损伤最为严重,表现为明显的变性、坏死和炎症细胞浸润,并在一些病变组织细胞浆内见嗜酸性或嗜碱性包涵体。针对蛙病毒(Ranavirus)病毒的特异性PCR检测扩增出蛙病毒主要衣壳蛋白(MCP)基因500 bp目的片段,测序后的DNA序列与Gen Bank中已知核酸序列进行Blast比对,发现其与Gen Bank中的蛙病毒主要衣壳蛋白基因同源性达95%~99%。根据组织病理特点及PCR检测结果推测大鳄龟的死亡是感染蛙病毒所致。