Lentivirus carrying the Atoh1 gene infects normal rat cochlea

Lentivirus carrying the Atoh1 gene can infect Corti’s organ and express a hair-like cell surface marker in the supporting cell area. However, expression of the gene carried by adenovirus is instantaneous, which undoubtedly limits its clinical application. Lentivirus acts as a carrier that can stably and continuously express genes. In this study, the cochlear structure and hearing level were not affected, and Atoh1 gene carried by lentivirus promoted the production of hair-like cells in the cochlear supporting cell area. This led to expression of the hair-like cell surface marker myosin 7a 30 days after lentivirus carrying Atoh1 was microinjected into the cochlear round window of rats.     

The top cited articles on glioma stem cells in Web of Science

BACKGROUND: Glioma is the most common intracranial tumor and has a poor patient prognosis. The presence of brain tumor stem cells was gradually being understood and recognized, which might be beneficial for the treatment of glioma. OBJECTIVE: To use bibliometric indexes to track study focuses on glioma stem cell, and to investigate the relationships among geographic origin, impact factors, and highly cited articles indexed in Web of Science. METHODS: A list of citation classics for glioma stem cells was generated by searching the database of Web of Science-Expanded using the terms "glioma stem cell" or "glioma, stem cell’" or "brain tumor stem cell". The top 63 cited research articles which were cited more than 100 times were retrieved by reading the abstract or full text if needed. Each eligible article was reviewed for basic information on subject categories, country of origin, journals, authors, and source of journals. Inclusive criteria: (1) articles in the field of glioma stem cells which was cited more than 100 times; (2) fundamental research on humans or animals, clinical trials and case reports; (3) research article; (4) year of publication: 1899-2012; and (5) citation database: Science Citation Index-Expanded. Exclusive criteria: (1) articles needing to be manually searched or accessed only by telephone; (2) unpublished articles; and (3) reviews, conference proceedings, as well as corrected papers. RESULTS: Of 2 040 articles published, the 63 top-cited articles were published between 1992 and 2010. The number of citations ranged from 100 to 1 754, with a mean of 280 citations per article. These citation classics came from nineteen countries, of which 46 articles came from the United States. Duke University and University of California, San Francisco led the list of classics with seven papers each. The 63 top-cited articles were published in 28 journals, predominantly Cancer Research and Cancer Cell, followed by Cell Stem Cell and Nature. CONCLUSION: Our bibliometric analysis provides a historical perspective on the progress of glioma stem cell research. Articles originating from outstanding institutions of the United States and published in high-impact journals are most likely to be cited.     

Differentiation renders susceptibility to excitotoxicity in HT22 neurons

HT22 is an immortalized mouse hippocampal neuronal cell line that does not express cholinergic and glutamate receptors like mature hippocampal neurons in vivo.This in part prevents its use as a model for mature hippocampal neurons in memory-related studies.We now report that HT22 cells were appropriately induced to differentiate and possess properties similar to those of mature hippocampal neurons in vivo,such as becoming more glutamate-receptive and excitatory.Results showed that sensitivity of HT22 cells to glutamate-induced toxicity changed dramatically when comparing undifferentiated with differentiated cells,with the half-effective concentration for differentiated cells reducing approximately two orders of magnitude.Moreover,glutamate-induced toxicity in differentiated cells,but not undifferentiated cells,was inhibited by the N-methyl-Daspartate receptor antagonists MK-801 and memantine.Evidently,differentiated HT22 cells expressed N-methyl-D-aspartate receptors,while undifferentiated cells did not.Our experimental findings indicated that differentiation is important for immortalized cell lines to render post-mitotic neuronal properties,and that differentiated HT22 neurons represent a better model of hippocampal neurons than undifferentiated cells.     

Screening of cerebral infarction-related genetic markers using a Cox regression analysis between onset age and heterozygosity at randomly selected short tandem repeat loci

The aim of this paper is to explore whether the heterozygosity at the 9 CODIS short tandem repeats (STR) loci including D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317 and D7S820 is associated with the risk of atherosclerotic cerebral infarction (CI). The DNA samples were collected from patients with CI (n = 72) and people over the age of 90 years without CI (n = 59). Alleles of the STR loci were determined using the STR Profiler Plus PCR amplification kit. The relationship between the age of onset and heterozygosity was determined with the Cox regression method. A correlation between the age of onset and heterozygosity was observed for the D8S1179 locus (p < 0.05). It implied that regions in the vicinity of locus D8S1179 may harbor susceptibility genes for CI. The analysis of heterozygosity for particular loci as genetic markers using our new study design may be an efficient and reliable approach to estimate genetic predispositions.     

MiR-663a Inhibits Radiation-Induced Epithelium-to-Mesenchymal Transition by Targeting TGF-β1

Objective miR-663 a has been reported to be downregulated by X-ray irradiation and participates in radiation-induced bystander effect via TGF-β1. The goal of this study was to explore the role of mi R-663 a during radiation-induced Epithelium-to-mesenchymal transition(EMT).Methods TGF-β1 or IR was used to induce EMT. After mi R-663 a transfection, cell migration and cell morphological changes were detected and the expression levels of mi R-663 a, TGF-β1, and EMT-related factors were quantified.R...     

高脂饮食对孕鼠子痫前期样改变及神经元mGluR1影响研究

目的探讨高脂饮食对孕鼠子痫前期样改变及神经元m GluR1的影响。方法将40只雌性大鼠随机分为非孕对照组(NN组)、妊娠对照组(PN组)、非孕高脂饮食组(NF组)及妊娠高脂饮食组(PF组),每组各10只。测量4组雌性大鼠收缩压、尿蛋白及血清生化指标;RT-PCR、Western Blot检测代谢型谷氨酸受体(m GluR1)mRNA及蛋白表达。结果孕鼠妊娠第16、20天,PF组收缩压明显高于NN组、PN组、NF组(P<0.05)。孕鼠妊娠第15、19天,PF组24 h尿蛋白含量明显高于NN组、PN组、NF组(P<0.05)。NF组TG、LDL-C、FFA、Lp-PLA2、LDL-C/HDL-C明显高于NN组,HDL-C明显低于NN组(P<0.05)。PF组TG、LDL-C、FFA、Lp-PLA2、LDL-C/HDL-C明显高于PN组,HDL-C明显低于PN组(P<0.05)。PF组TG、LDL-C、FFA、Lp-PLA2、HDL-C明显高于NF组(P<0.05)。RT-PCR及Western blot检测显示,PF组m GluR1 mRNA及蛋白表达明显增强,高于NN组、PN组、NF组(P<0.05)。结论高脂饮食可诱发孕鼠子痫前期样改变,m GluR1 mRNA及蛋白表达上调可促进子痫发生。     

液体活检在消化道肿瘤诊治中的应用进展

液态活检作为一种新兴的无创检测技术,主要包括循环肿瘤细胞、循环肿瘤DNA、微小RNA以及外泌体等生物标志物的检测,在肿瘤早期诊断、监测疾病进展以及疗效评价等方面的应用日趋普遍。近年来,以胰腺癌、结直肠癌和胃癌等为代表的消化系统肿瘤成为威胁我国人民群众身体健康的重要疾病负担,并且多数患者确诊时已为中晚期。因此,如何完善消化系统肿瘤的诊断和筛查手段,延长患者的生存期,是当前的研究重点。本文就液态活检在消化系统肿瘤诊治中的临床应用现状和前景进行探讨。     

Potential risk of mitomycin Cat high concentrations on peripheral nerve structure

Although the local application of mitomycin C may prevent epidural adhesion after laminectomy, mitomycin C can induce neurotoxicity in optic and acoustic nerves at high concentrations. To determine the safe concentration range for mitomycin C, cotton pads soaked with mitomycin C at different concentrations(0.1, 0.3, 0.5, and 0.7 mg/mL) were immediately applied for 5 minutes to the operation area of rats that had undergone laminectomy at L1. Rat sciatic nerves, instead of dorsal nerves, were used in this study. The results showed that mitomycin C at 0.1–0.5 mg/mL did not damage the structure and function of the sciatic nerve, while at 0.7 mg/mL, mitomycin C significantly reduced the thickness of the sciatic nerve myelin sheath compared with lower concentrations, though no functional change was found. These experimental findings indicate that the local application of mitomycin C at low concentrations is safe to prevent scar adhesion following laminectomy, but that mitomycin C at high concentrations( 0.7 mg/mL) has potential safety risks to peripheral nerve structures.     

Local inhibition of GABA affects precedence effect in the inferior colliculus

The precedence effect is a prerequisite for faithful sound localization in a complex auditory environment, and is a physiological phenomenon in which the auditory system selectively suppresses the directional information from echoes. Here we investigated how neurons in the inferior colliculus respond to the paired sounds that produce precedence-effect illusions, and whether their firing behavior can be modulated through inhibition with gamma-aminobutyric acid （GABA）. We recorded extracellularly from 36 neurons in rat inferior colliculus under three conditions： no injection, injection with saline, and injection with gamma-aminobutyric acid. The paired sounds that produced precedence effects were two identical 4-ms noise bursts, which were delivered contralaterally or ipsilaterally to the recording site. The normalized neural responses were measured as a function of different inter-stimulus delays and half-maximal interstimulus delays were acquired. Neuronal responses to the lagging sounds were weak when the inter-stimulus delay was short, but increased gradually as the delay was lengthened. Saline injection produced no changes in neural responses, but after local gamma-arninobutyric acid application, responses to the lagging stimulus were suppressed. Application of gamma-aminobutyric acid affected the normalized response to lagging sounds, independently of whether they or the paired sounds were contralateral or ipsilateral to the recording site. These observations suggest that local inhibition by gamma-aminobutyric acid in the rat inferior colliculus shapes the neural responses to lagging sounds, and modulates the precedence effect.