国内110株新生隐球菌临床株变种、基因型和交配型分析

目的 对国内部分地区的新生隐球菌(Cryptococcus neoformans)临床株进行分子流行病学调查,分析其变种、基因型和交配型的构成和分布.方法 (1)PCR指纹分型法:以野生型噬菌体M13中针对小卫星DNA的核心序列为单引物对模板进行PCR扩增,将所有受试菌株鉴定到8种主要基因型水平.(2)利用变种和交配型特异性引物扩增分型法,区分格鲁比变种(C.neoformans var.grubii)、新生变种(C.neoformans var.neoformans)和格特变种(C.neoformans var.gattii),同时鉴定α和a交配型.结果 110株临床株中,98株(89.1%)为格鲁比变种,均为VNI基因型和α交配型;9株(8.2%)格特变种,包括VGⅠ基因型、α交配型8株(7.3%)和VGⅡ基因型、α交配型1株(0.9%);2株(1.8%)为AD杂合体,VNⅢ基因型,-/α和α/-交配型各1株;1株(0.9%)为新生变种,VNⅣ基因型和a交配型.结论 我国新生隐球菌临床株包含3个变种和AD杂合体.与国外情况比较,相似的是国内临床株中绝大部分为α交配型菌株,且格鲁比变种中的VNⅠ基因型占了其中的大部分;但未发现VNⅡ、VGⅢ和VGⅣ基因型菌株.     

食管癌筛查队列操作流程与建设标准方案探讨

癌症防治工作的重点在于一级预防和二级预防,通过健康教育引起人们对疾病的重视、自觉改变不良行为习惯、主动参加定期体检是防治癌症性价比最高的措施之一。食管癌作为我国疾病负担较重的恶性肿瘤之一,定期筛查和早诊早治是该病防治工作的重点。而队列研究有助于了解食管癌的自然史和危险因素、识别食管癌高危人群。本研究拟从危险因素调查、疾病监测、生物样本信息搜集等方面对食管癌多维动态随访共享队列的建设规范进行探讨,为今后建立规范统一的食管癌筛查队列研究操作流程和建设标准提供参考。     

我国干细胞临床研究管理现状及对策思考

近年来,干细胞治疗已经成为一个极具发展前景的前沿科学研究领域,其治疗方法的发展给患者及家属带来了极大的期望。然而,随着我国干细胞临床研究项目数量的不断增加,干细胞临床研究与应用中存在的伦理和安全问题日益突出,使我国监督管理部门和研究机构面临着前所未有的挑战。本文通过分析我国干细胞临床研究的管理现状和存在的问题,探讨加强干细胞临床研究监督和研究机构内部管理规范的措施,为有效推进我国干细胞临床研究的有序、规范发展提出相应对策。     

Early stages of chick somite development

We report on the formation and early differentiation of the somites in the avian embryo. The somites are derived from the mesoderm which, in the body (excluding the head), is subdivided into four compartments: the axial, paraxial, intermediate and lateral plate mesoderm. Somites develop from the paraxial mesoderm and constitute the segmental pattern of the body. They are formed in pairs by epithelialization, first at the cranial end of the paraxial mesoderm, proceeding caudally, while new mesenchyme cells enter the paraxial mesoderm as a consequence of gastrulation. After their formation, which depends upon cell-cell and cell-matrix interactions, the somites impose segmental pattern upon peripheral nerves and vascular primordia. The newly formed somite consists of an epithelial ball of columnar cells enveloping mesenchymal cells within a central cavity, the somitocoel. Each somite is surrounded by extracellular matrix material connecting the somite with adjacent structures. The competence to form skeletal muscle is a unique property of the somites and becomes realized during compartmentalization, under control of signals emanating from surrounding tissues. Compartmentalization is accompanied by altered patterns of expression of Pax genes within the somite. These are believed to be involved in the specification of somite cell lineages. Somites are also regionally specified, giving rise to particular skeletal structures at different axial levels. This axial specification appears to be reflected in Hox gene expression. MyoD is first expressed in the dorsomedial quadrant of the still epithelial somite whose cells are not yet definitely committed. During early maturation, the ventral wall of the somite undergoes an epithelio-mesenchymal transition forming the sclerotome. The sclerotome later becomes subdivided into rostral and caudal halves which are separated laterally by von Ebner's fissure. The lateral part of the caudal half of the sclerotome mainly forms the ribs, neural arches and pedicles of vertebrae, whereas within the lateral part of the rostral half the spinal nerve develops. The medially migrating sclerotomal cells form the peri-notochordal sheath, and later give rise to the vertebral bodies and intervertebral discs. The somitocoel cells also contribute to the sclerotome. The dorsal half of the somite remains epithelial and is referred to as the dermomyotome because it gives rise to the dermis of the back and the skeletal musculature. The cells located within the lateral half of the dermomyotome are the precursors of the muscles of the hypaxial domain of the body, whereas those in the medial half are precursors of the epaxial (back) muscles. Single epithelial cells at the cranio-medial edge of the dermomyotome elongate in a caudal direction, beneath the dermomyotome, and become anchored at its caudal margin. These post-mitotic and muscle protein-expressing cells form the myotome. At limb levels, the precursors of hypaxial muscles undergo an epithelio-mesenchymal transition and migrate into the somatic mesoderm, where they replicate and later differentiate. These cells express the Pax-3 gene prior to, during and after this migration. All compartments of the somite contribute endothelial cells to the formation of vascular primordia. These cells, unlike all other cells of the somite, occasionally cross the midline of the developing embryo. We also suggest a method for staging somites according to their developmental age.     

Comparative analysis of proneural gene expression in the embryonic cerebellum

The embryonic cerebellum contains two germinative epithelia: the rhombic lip and the ventricular zone. While the lineage of glutamatergic neurons arising from the rhombic lip has been characterized, plenty remains to be learned about the factors giving rise to the array of ventricular zone-derived gamma-aminobutyric acid (GABA)ergic neurons. In the present study, we describe the expression of proneural genes Mash1/Ascl1, Ngn1/Neurog1, and Ngn2/Neurog2 in the cerebellar primordium at key stages of Purkinje cell and interneuron development, and compare them with the expression of other genes active in the same context. Our results indicate that Ngn1, Ngn2 and Mash1 are expressed at relevant stages of cerebellar neurogenesis in the prospective cerebellar nuclei and in the ventricular zone, excluding the Math1/Atoh1-positive rhombic lip. Their expression domains are only partially overlapping, suggesting that they may contribute selectively to ventricular zone regionalization, giving rise to the diversity of cerebellar GABA neurons and, possibly, Purkinje cell subtypes.     

《浙江省中药炮制规范》2015年版收载品种的变化情况

目的 介绍《浙江省中药炮制规范》2015年版收载品种的变化情况。方法 分为地方习用品种和独特炮制方法、新增品种和新炮制工艺品种进行介绍。结果 《浙江省中药炮制规范》2015年版共收载632个品种,数量较2005年版大幅减少,结论 《浙江省中药炮制规范》2015年版接轨中国药典大幅提高质量标准,并扩大了先进检测技术的应用。     

牛膝指纹图谱分析

目的:对不同产地牛膝药材、同一产地不同规格牛膝药材的HPLC指纹图谱进行研究,比较不同产地牛膝药材、同一产地不同规格牛膝药材的HPLC指纹图谱差异,探讨产地、规格对牛膝药材质量的影响及规格与牛膝药材内部质量的联系;为牛膝药材的产地鉴别提供理论依据;为牛膝药材质量标准制定、规格完善及临床用药提供参考。方法:采用超声提取法制备样品,通过HPLC法采集不同产地牛膝药材、同一产地不同规格牛膝药材的指纹图谱,运用相似度、聚类分析、主成分分析的方法进行分析,并比较不同产地牛膝药材、不同规格牛膝药材的HPLC指纹图谱差异。结果:不同产地分析,主成分分析能将5个产地牛膝药材区分开,且产地鉴别结果优于聚类分析和相似度分析。不同规格分析,相似度和主成分分析均不能将不同规格牛膝药材区分开。结论:不同产地牛膝药材化学成分种类、峰高差异显著;不同规格牛膝药材化学成分种类、峰高差异较小;主成分分析可用于牛膝药材的产地鉴别。     

Probing early heart development to instruct stem cell differentiation strategies

Scientists have studied organs and their development for centuries and, along that path, described models and mechanisms explaining the developmental principles of organogenesis. In particular, with respect to the heart, new fundamental discoveries are reported continuously that keep changing the way we think about early cardiac development. These discoveries are driven by the need to answer long‐standing questions regarding the origin of the earliest cells specified to the cardiac lineage, the differentiation potential of distinct cardiac progenitor cells, and, very importantly, the molecular mechanisms underlying these specification events. As evidenced by numerous examples, the wealth of developmental knowledge collected over the years has had an invaluable impact on establishing efficient strategies to generate cardiovascular cell types ex vivo, from either pluripotent stem cells or via direct reprogramming approaches. The ability to generate functional cardiovascular cells in an efficient and reliable manner will contribute to therapeutic strategies aimed at alleviating the increasing burden of cardiovascular disease and morbidity. Here we will discuss the recent discoveries in the field of cardiac progenitor biology and their translation to the pluripotent stem cell model to illustrate how developmental concepts have instructed regenerative model systems in the past and promise to do so in the future. Developmental Dynamics 245:1130–1144, 2016. © 2016 Wiley Periodicals, Inc.     

Amnioserosa development and function in Drosophila embryogenesis: Critical mechanical roles for an extraembryonic tissue

Despite being a short‐lived, extraembryonic tissue, the amnioserosa plays critical roles in the major morphogenetic events of Drosophila embryogenesis. These roles involve both cellular mechanics and biochemical signaling. Its best‐known role is in dorsal closure—well studied by both developmental biologists and biophysicists—but the amnioserosa is also important during earlier developmental stages. Here, we provide an overview of amnioserosa specification and its role in several key developmental stages: germ band extension, germ band retraction, and dorsal closure. We also compare embryonic development in Drosophila and its relative Megaselia to highlight how the amnioserosa and its roles have evolved. Placed in context, the amnioserosa provides a fascinating example of how signaling, mechanics, and morphogen patterns govern cell‐type specification and subsequent morphogenetic changes in cell shape, orientation, and movement. Developmental Dynamics 245:558–568, 2016. © 2016 Wiley Periodicals, Inc.