HDAC1 Regulates the Proliferation of Radial Glial Cells in the Developing Xenopus Tectum

In the developing central nervous system (CNS), progenitor cells differentiate into progeny to form functional neural circuits. Radial glial cells (RGs) are a transient progenitor cell type that is present during neurogenesis. It is thought that a combination of neural trophic factors, neurotransmitters and electrical activity regulates the proliferation and differentiation of RGs. However, it is less clear how epigenetic modulation changes RG proliferation. We sought to explore the effect of histone deacetylase (HDAC) activity on the proliferation of RGs in the visual optic tectum of Xenopus laevis. We found that the number of BrdU-labeled precursor cells along the ventricular layer of the tectum decrease developmentally from stage 46 to stage 49. The co-labeling of BrdU-positive cells with brain lipid-binding protein (BLBP), a radial glia marker, showed that the majority of BrdU-labeled cells along the tectal midline are RGs. BLBP-positive cells are also developmentally decreased with the maturation of the brain. Furthermore, HDAC1 expression is developmentally down-regulated in tectal cells, especially in the ventricular layer of the tectum. Pharmacological blockade of HDACs using Trichostatin A (TSA) or Valproic acid (VPA) decreased the number of BrdU-positive, BLBP-positive and co-labeling cells. Specific knockdown of HDAC1 by a morpholino (HDAC1-MO) decreased the number of BrdU- and BLBP-labeled cells and increased the acetylation level of histone H4 at lysine 12 (H4K12). The visual deprivation-induced increase in BrdU- and BLBP-positive cells was blocked by HDAC1 knockdown at stage 49 tadpoles. These data demonstrate that HDAC1 regulates radial glia cell proliferation in the developing optical tectum of Xenopus laevis.     

Depression among Migrant and Left-Behind Children in China in Relation to the Quality of Parent-Child and Teacher-Child Relationships

The objective of this study was to examine rates of depression among migrant children (MC) and left-behind children (LBC) as compared to non-left-behind children (NLBC) and also to examine the relationship between depression among these children and the quality of their parent-child and teacher-child relationships. This study collected data from a large sample of 3,759 children aged from 8 to 17 years, including 824 who had been left behind by one parent (LBCO), 423 who had been left behind by both parents (LBCB), 568 MC and 1944 NLBC. Children’s Depression Inventory–Short Form was used to measure child depression. Parent-Child Relationship Scale (PCRS) and Teacher-Child Relationship Scale (TCRS) were used to measure the quality of parent-child and teacher-child relationships, respectively. The results showed that the prevalence of depression was 10.5% among NLBC, 13.1% among LBCO, 16.1% among LBCB, and 20.1% among MC. Depression was related to parent-child relationship quality and teacher-child relationship quality. Negative parent-child relationship was more relevant to depression than negative teacher-child relationship among LBCB, while negative teacher-child relationship was the most correlated with depression among MC.     

一种新型免疫层析技术在临床乳腺癌Her-2蛋白定量检测中的应用

建立一种靶点蛋白质快速定量检测方法。在原有侧向流动免疫层析技术的基础上,通过优化层析材料和纳米微球的均一性、改进检测区的检测方法,经逐点扫描技术,建立标准浓度曲线,以达到对临床靶点蛋白质的定量检测。以乳腺癌组织中的Her2表达为例,通过对已知浓度样品的检测,验证本技术方法的准确度大于96%。另外,以蛋白质免疫印迹作为组织中特定蛋白质检测金标准,分析临床肿瘤组织中Her2蛋白的含量,其准确率也达到95.5%,而免疫组织化学方法检测准确率仅为69.58%。新型免疫层析法检测结果与靶向治疗患者的愈后密切相关(P<0.01)。改进后的新型免疫层析方法能够准确地对临床靶点蛋白质进行定量检测,而且结合侧向流动技术的简单、快速和易用性,这种新型检测方法可以广泛应用于临床组织标本、血液标本和体液标本中靶点蛋白质的临场定量检测,在一定程度上可以替代免疫组化技术。     

荒漠灌丛土壤动物分布及其生态功能

在干旱、半干旱荒漠生态系统中,灌丛作为一种重要的植被类型,其独特的形态和生理适应特性能够有效促进退化生态系统结构与功能的恢复。土壤动物是荒漠生态系统中不可或缺的重要组成部分,对促进灌丛"肥岛"演变具有重要的生态作用,有利于灌丛生态功能的发挥及退化生态系统的恢复。近年来,国内外学者对荒漠灌丛微生境土壤动物的研究逐步深入,取得大量的研究成果。在此基础上,首先综述荒漠灌丛微生境土壤动物群落分布和生态功能,总结灌丛与土壤动物分布间作用关系的数学模型,针对荒漠灌丛土壤动物研究中存在的问题提出了未来可能的研究方向和建议。     

Horizon of the oldest known bryozoans (Ordovician)

Among the six species of fossil bryozoans described by Xia et al. [Xia, F.S., Zhang, S.G., Wang, Z.Z., 2007. The oldest bryozoans: new evidence from the late Tremadocian (Early Ordovician) of East Yangtze Gorges. Journal of Paleontology 81 (6), 1308–1326] from the Fenghsiang Formation of the Chenjiahe section of Yichang and the Guanzhuangping section, Liujiachang Town of Songzi, the Yangtze Gorges, Nekhorosheviella nodulifera occurs in the pristinus Conodont Subzone (lower Subzone of deltifer Conodont Zone) and the five other species are associated with the conodont Paltodus deltifer deltifer and the graptolites Acanthograptus sinensis and A. erectoramus. Based on the conodonts and graptolites, this bryofauna stratigraphically corresponds to the A. sinensis Graptolite Zone or P. deltifer Conodont Zone. The bryofauna is of Tremadocian Age (Early Ordovician) and represents the oldest bryozoans so far as known.