微小RNA在卵巢颗粒细胞中的研究进展

微小RNA(microRNAs,miRNAs)是一类内源性非编码RNA,可以在转录后水平通过对靶基因的调控,影响蛋白质的表达,其参与调节各个环节的细胞生命活动。特定的miRNAs低表达、过表达或者变异都可能引起细胞功能的异常。卵巢颗粒细胞是卵泡中最重要的体细胞,其围绕在卵母细胞周围,可合成多种激素及生长因子,并表达其受体,通过缝隙连接调控卵泡膜细胞和卵母细胞的生长、分化和成熟,进而调控卵泡的发育。MiRNAs在卵泡发育过程中的作用除了miRNAs对卵母细胞的直接作用外,其在颗粒细胞中的调控作用也尤为重要。研究发现,miRNAs在卵巢颗粒细胞的增殖与分化、凋亡、性激素分泌等过程中发挥重要的作用。本文综述近年卵巢颗粒细胞中miRNAs的研究进展。     

血液中微小RNA检测与肿瘤的诊断、治疗和预后

微小RNA(microRNA,miRNA)是一组非编码的小分子RNA,由大约22个核苷酸组成,单链,内源性,广泛存在于生物界[1].miRNA与靶mRNA的3'端非编码区域(3'-untranslated region,3'-UTR)结合,通过靶mRNA切割或翻译抑制的方式发挥调控靶基因表达的作用.miRNA调控的很多靶基因都是生物体生长、发育、凋亡和代谢、肿瘤发生等许多过程中的关键成员.不同组织或细胞在不同阶段表达的miRNA种类和数量不同,其表达具有高度的组织特异性、保守性和时序性.     

微小RNA与宫颈癌

微小RNA（microRNA,miRNA）是一类内源性非编码调节性小RNA,通过与3′非转录区（3′UTR）互补配对来调节其靶基因的蛋白翻译或者mRNA降解过程,从而在转录后水平调节靶基因的表达。成熟的miRNA通过调节靶基因的表达行使其生物学功能,参与细胞增长、细胞凋亡等多种细胞癌变过程。研究表明,miRNA在宫颈癌中的差异性表达有可能使其成为诊断、临床病理学特征和评价预后的新指标。miRNA也可以用于指导治疗以及成为治疗用药的靶点,为临床应用提供广泛前景。     

微小RNA与宫颈癌

微小RNA（microRNA,miRNA）是一类内源性非编码调节性小RNA,通过与3’非转录区（3’UTR）互补配对来调节其靶基因的蛋白翻译或者mRNA降解过程,从而在转录后水平调节靶基因的表达。成熟的miRNA通过调节靶基因的表达行使其生物学功能,参与细胞增长、细胞凋亡等多种细胞癌变过程。研究表明,miRNA在宫颈癌中的差异性表达有可能使其成为诊断、临床病理学特征和评价预后的新指标。miRNA也可以用于指导治疗以及成为治疗用药的靶点,为临床应用提供广泛前景。     

微小RNA和生殖

微小RNA(microRNA,miRNA)是一种长度约19～25个核苷酸的非编码RNA,通过碱基互补配对与mRNA的3’非翻译区结合降解靶基因或抑制其翻译,进行转录后负调控。迄今,上千种miRNA得到成功鉴定。miRNA不但在细胞的增殖、分化、凋亡、组织更新和干细胞分化过程中发挥作用,且参与生殖细胞发育、成熟和胚胎早期发育、激素分泌等生殖调节。     

微小RNA和生殖

微小RNA(microRNA,miRNA)是一种长度约19～25个核苷酸的非编码RNA,通过碱基互补配对与mRNA的3’非翻译区结合降解靶基因或抑制其翻译,进行转录后负调控。迄今,上千种miRNA得到成功鉴定。miRNA不但在细胞的增殖、分化、凋亡、组织更新和干细胞分化过程中发挥作用,且参与生殖细胞发育、成熟和胚胎早期发育、激素分泌等生殖调节。     

微小RNA和生殖

微小RNA（microRNA,miRNA）是一种长度约19～25个核苷酸的非编码RNA,通过碱基互补配对与mRNA的3’非翻译区结合降解靶基因或抑制其翻译,进行转录后负调控。迄今,上千种miRNA得到成功鉴定。miRNA不但在细胞的增殖、分化、凋亡、组织更新和干细胞分化过程中发挥作用,且参与生殖细胞发育、成熟和胚胎早期发育、激素分泌等生殖调节。     

MicroRNA参与多囊卵巢综合征代谢紊乱的研究进展

<正>微小RNA(microRNA,miRNA)是一类小分子非编码RNA,广泛存在于多囊卵巢综合征(polycystic ovariansyndrome,PCOS)患者的外周血和组织液中,影响PCOS代谢紊乱的发病及进展,其通过与靶基因信使RNA(messenger RNA,mRNA)的特定位点结合,抑制该基因编码蛋白的合成或诱导mRNA的降解,从而参与基因表达的转录后调控^[1]。miRNA能够调节人体近1/3的基因,广泛参与细胞生长、发育、分化、凋亡及细胞周期调控等活动,在生理、发育和控制基因转录后表达的过程中扮演着至关重要的角色^[2],     

miR-23a和miR-27a在卵巢中的生理与病理作用

微小RNA (microRNA,miRNA)在转录后水平调控靶基因表达,因而在细胞增殖、分化、凋亡、存活及肿瘤的发生、发展中起重要作用.卵巢中存在多种miRNA的表达,miR-23a和miR-27a是miR-23a～27a～24-2家族成员,通过依赖caspase及非依赖caspase途径发挥促进凋亡的作用,且可以引发内质网应激过程.研究发现,miR-23a和miR-27a涉及卵巢卵泡发育、激素合成与分泌以及卵巢早衰、卵巢癌等卵巢相关病理过程.miRNA对卵巢功能的调控作用逐渐被揭示,对不孕症和某些卵巢疾病的创新治疗有一定帮助.就miR-23a和miR-27a在卵巢中的生理与病理作用进行综述.     

miRNA在宫颈癌中的研究进展

微小RNA（microRNA,miRNA）是一类长度为19—25个核苷酸的非编码小分子RNA。miRNA能够识别特定的目标mRNA,并在转录后通过促进mRNA的降解和（或）抑制翻译过程而发挥负调控基因表达作用。miRNA在生物进化过程中具有高度保守性、时序性和组织特异性,在细胞凋亡、脂肪代谢、神经元发育、细胞分化、激素分泌及肿瘤发生发展等多种生理和病理过程中发挥重要作用。本文就近年来miRNA在宫颈癌方面的研究做一综述。     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.