Mesothelial differentiation as reflected by differential gene expression

Human mesothelial cells obtained from benign effusions retain their proliferative capacity and grow uniformly either with a fibroblastic or epithelioid morphology in vitro. These cultures therefore provide a model for the process of mesothelial differentiation in vivo. To study this differentiation, we isolated differentially expressed genes obtained by suppression subtractive hybridization. Of the nine genes found to be overexpressed in fibroblastic mesothelial cells, three are matrix-associated (integrin alpha5, collagen binding protein 2, human cartilage glycoprotein 39), whereas the others are associated with a proliferative cell type (14-3-3 epsilon, plexin B2, N33, and three genes encoding ribosomal elements). Seven of the eight genes upregulated in the epithelioid phenotype are related rather to specialized functions, such as metabolism (aldose reductase, lecithin:cholesterol acyltransferase, ATPase 6), cytoskeletal composition (cytokeratins 7 and 8), and regulation of differentiation (granulin, annexin II). Immunohistochemistry with available antibodies to six of the differentially expressed gene products confirmed the differences also in pleural tissues, where submesothelial cells displayed the fibroblastic markers, whereas surface cells displayed the epithelioid markers. In summary, this approach revealed a pattern of genes coordinately regulated during mesothelial differentiation and suggests that mesothelium may regenerate also by recruiting cells from the submesothelial layer. Some of the gene products may also be useful markers for differentiation and activation in serosal tissues.     

Effect of aging on neuroglobin expression in rodent brain

Neuroglobin (Ngb), a recently discovered O2-binding heme protein related to hemoglobin and myoglobin, protects neurons from hypoxic-ischemic injury in vitro and in vivo. In immunostained mouse brain sections, we found widespread expression of Ngb protein in neurons, but not astrocytes, of several brain regions that are prominently involved in age-related neurodegenerative disorders. Western blots from young adult (3 month), middle-aged (12 month), and aged (24 month) rats showed an age-related decline in Ngb expression in cerebral neocortex, hippocampus, caudate-putamen, and cerebellum. Loss of this neuroprotective protein may have a role in increasing susceptibility to age-related neurological disorders.     

GDNF-induced seminomatous tumours in mouse--an experimental model for human seminomas?

Glial-cell-line-derived neurotrophic factor (GDNF) is a distant member of the transforming growth factor superfamily. It binds to and activates a receptor complex consisting of GFR-alpha1 and Ret receptor tyrosine kinase. In testis, GDNF is expressed by Sertoli cells. We have shown by transgenic loss- and gain-of-function mouse models that GDNF regulates the cell fate decision of undifferentiated spermatogonia. In the GDNF +/- mice, the spermatogonia differentiate in excess leading to the depletion of germ cells. In the mice overexpressing GDNF in testes, undifferentiated spermatogonia accumulate in the tubules, no sperm is produced, and the mice are infertile. After a year, the GDNF overexpressing mice frequently (89%) develop testicular tumours, and most of them are bilateral (56%). All these tumours show the same histological pattern. They are composed of round spermatogonial/gonocytic cells with only a scant cytoplasm. The tumours are locally invasive but do not metastasise. They express germ line markers, are positive for alkaline phosphatase, and aneuploid with a triploid peak. Thus, by several histological, molecular, and histochemical characteristics, the GDNF-induced tumours mimic classical seminomas in men, but the precursor lesions are apparently different in mouse and man.     

大肠癌的靶向治疗

大肠癌是常见的恶性肿瘤之一,发病率及死亡率亦逐年上升,严重威胁人们的生命。目前对大肠癌的治疗仍是以手术为主、辅以局部或全身放疗及化疗的综合治疗。早期大肠癌手术治疗效果明确,但有20～25%左右的患者在首诊时已有其它器官的转移给治疗带来了困难。而靶向治疗作为一种新的治疗手段,为晚期大肠癌的治疗开辟了新途径。     

以学生为案例望面色教学实践体会

望面色是望诊的主要内容之一,为了加强学生望面色这一诊断方法的学习效果,在征得学生同意,自愿参加的前提下,在学生中找典型面色进行真实案例教学,调动了学生学习积极性,取得了良好教学效果,实现了教学相长。     

延续性护理模式在椎动脉型颈椎病患者中的应用效果分析

目的:观察延续性护理模式在椎动脉型颈椎病患者中的应用效果。方法:将100例椎动脉型颈椎病患者随机分为观察组、对照组各50例。观察组采用延续性护理模式配合优质护理服务进行临床护理,对照组采用常规护理模式进行护理。观察2组颈椎功能障碍指数,自我护理能力及遵医嘱情况。结果:颈椎功能障碍指数出院后3个月、出院时与入院时2组组内比较,差异有统计学意义(P0.05);出院后3个月与出院时2组组内比较,差异有统计学意义(P0.05);出院时、出院后3个月时2组组间比较,差异有统计学意义(P0.05)。自我护理能力2组比较差异有统计学意义(P0.05);遵医嘱情况2组比较,差异有统计学意义(P0.05)。结论:延续性护理模式能缓解患者的临床症状,提高患者的自我护理能力,促提高患者的遵医情况。     

乌鲁木齐地区线粒体12SrRNA基因突变筛查分析

目的　研究乌鲁木齐地区非综合征性聋患者线粒体12S rRNA基因突变情况。方法　收集乌鲁木齐非综合征性聋患者标本609例,对其进行临床和分子遗传学评估。结果　12S rRNA基因突变分析共发现11个突变位点,已知的A1555G、961DelT、C1494T突变分别占2.96%,1.15%,0.16%。另外A1047G突变相关报道较少,A1585G突变未见相关报道。其他突变均为多态性位点。结论　线粒体12S rRNA突变是引起遗传性聋的重要因素,此次乌鲁木齐地区线粒体12S rRNA A1555G突变在聋病人群中的检出率与前期报道相比有所降低,可能与耳毒性药物使用量降低有关。A1047G与新发现的A1585G突变是否与聋相关,还需进一步研究。对筛查中阳性突变携带者及其母系家庭成员需告知氨基糖苷类抗生素使用风险,使其避免使用,逐步降低药物性聋的发生率。