Immunohistochemical analysis of centromere protein F expression in buccal and gingival squamous cell carcinoma

Centromere protein F (CENP-F) expression (localization and characteristics) in relation to tumor clinicopathological parameters was immunohistochemically examined and evaluated in 47 archival biopsy specimens of buccal and gingival squamous cell carcinomas (SCC). Centromere protein F expression was detected in 79% of the samples. An increase in the labeling index (LI) with WHO grading was obtained ( P  < 0.05). Correlations were obtained between the CENP-F LI and tumor size ( P  < 0.05). Immunoelectron microscopy showed CENP-F nuclear staining as punctate or fine dots. The present study shows that CENP-F expression and detection of a more specific cell subpopulation presents a theoretical advantage for the analysis of the precise cell cycle of G₂ to M cells, compared to Ki-67.     

Application of simulated annealing for estimating BAEPs in endocochlear pathologies

In this paper, we propose a new approach aimed at handling the temporal Brainstem Auditory Evoked Potentials (BAEPs) non-stationarity. It is pointed out that for some endocochlear pathologies, BAEPs could be randomly delayed from one response to another. This non-stationarity leads to smoothed BAEPs when applying ensemble averaging or any other technique based on BAEPs stationarity. In that case, waves identification is very difficult, sometimes impossible. The problem consists in estimating time delays. Knowing the distribution of delays allows subsequent study of the dynamic of the cochlea and, perhaps, identification of the nature of its pathology. The approach suggested in this paper is based on Simulated Annealing, used to minimize a non-linear criterion involving delays. This technique is advantageously compared to the non-corrected ensemble averaging method, using a set of simulated data based on a realistic model. As an illustration, results based on real signals recorded from two patients are presented and discussed at the end of the paper.     

川芎嗪对内毒素脂多糖诱导的体外血脑屏障模型通透性增高的保护作用及其机制

目的:探讨川芎嗪对内毒素脂多糖(LPS)诱导的体外血脑屏障模型通透性增高的保护作用及其调控机制。方法:利用脑微血管内皮细胞与星型胶质细胞共培养建立体外大鼠血脑屏障模型,随机分为正常对照组、川芎嗪对照组、LPS干预组和川芎嗪治疗组。采用γ计数仪检测~(125)I-BSA通透量观察体外血脑屏障模型通透性的改变,Western印迹法检测紧密连接蛋白(zonula occludens-1,ZO-1)表达量的变化。结果:LPS使体外血脑屏障模型对~(125)I-BSA的通透量明显增加,脑微血管内皮细胞ZO-1蛋白表达下降,川芎嗪治疗组能明显拮抗LPS的上述作用。结论:川芎嗪对LPS诱导的体外血脑屏障通透性增高具有保护作用,其机制与它能影响血脑屏障紧密连接蛋白ZO-1表达有关。     

Springer Link及其收录的医学期刊分析

目的：向图书馆员和用户介绍Springer Link，对其收录的医学期刊进行深入分析，使该数据库得到更好的利用。方法利用《外国报刊目录》和美国《医学索引》(IM)的《引用期刊一览表》等对Springer Link收录的英文医学期刊从权威性、出版地分布、学科分布和收藏年限等方面进行考查。结果86％的期刊被IM引用，欧洲——尤其是德国的期刊较多，医学各学科都有相应的期刊被收录，但数量分布不均，有所偏重，72．7％的期刊可以保证至少近5年或自创刊以来的文献。结论Springer Link所提供的全文医学期刊服务质量较上乘，并有自己的特色。     

小鼠下颔下腺中肥大细胞异质性研究

取小鼠下颌下腺,用甲苯胺蓝染色、Alcian蓝一藏红染色及免疫组织化学ABC法显示肥大细胞的异质性.结果表明;肥大细胞主要分布于间质的小血管、小叶间导管及神经节周围.此外还发现有些肥大细胞沿腺实质表面排列,有些肥大细胞伸出突起与相邻的神经元或肥大细胞接触.肥大细胞呈降钙素基因相关肽免疫反应阳性,但仅为相邻切片甲苯胺蓝染色的14 %.提示下颌下腺中肥大细胞的存在可能与腺体分泌活动及血流调节有关.     

Comparison of immunohistochemical markers in the differential diagnosis of adrenocortical tumors: immunohistochemical analysis of adrenocortical tumors.

Most adrenocortical tumors (ACTs) can be diagnosed directly by a combination of morphologic features and clinical findings. However, sometimes it may be difficult to distinguish ACTs from other neoplasms such as pheochromocytomas and some metastatic tumors, particularly for small biopsy specimens because they may be morphologically similar. Expression of calretinin has recently been suggested as a valuable immunomarker for the differential diagnosis between ACTs and other tumors; however, its diagnostic value is still under debate. To determine the diagnostic value of calretinin in Chinese patients with adrenocortical and non-ACTs, we employed both polyclonal and monoclonal anticalretinin to characterize the expression of calretinin in adrenal tissues and compared its expression with that of inhibin alpha, Melan-A, cytokeratin, or CD99 by immunohistochemistry in tissue microarrays and standard tissue sections of 414 specimens. Our results revealed that calretinin was expressed by adrenocortical cells, but not by the other cells tested and the percentage of calretinin-positive ACTs reached 99% when stained with polyclonal antibodies, which was higher than that with monoclonal anticalretinin (91.3%), anti-Melan-A (90.3%), antiinhibin alpha (81.6%). In addition, our results also revealed that ACTs were stained by cytokeratin (AE1/AE3) with variable degrees (58.7%). Furthermore, unlike anti-Melan-A that stained all metastatic malignant melanoma, anticalretinin did not recognize other tested tumors. Therefore, immunohistologic staining with polyclonal anticalretinin is more sensitive than other antibodies tested for the diagnosis of ACTs. However, monoclonal anticalretinin appeared to be more specific. Importantly, our data suggested that the fried-egg-like staining pattern, but not the mere cytoplasmic staining, was characteristic of anticalretinin staining in adrenocortical tissues. Notably, a few anticalretinin negative-ACTs were stained by other immunomarkers that we tested. Thus, the combinational characterization of calretinin (either by polyclonal or monoclonal antibody), inhibin alpha, and Melan-A expression is of great significance in the differential diagnosis of ACTs.     

In vitro degradation of silk fibroin

A significant need exists for long-term degradable biomaterials which can slowly and predictably transfer a load-bearing burden to developing biological tissue. In this study Bombyx mori silk fibroin yarns were incubated in 1mg/ml Protease XIV at 37 degrees C to create an in vitro model system of proteolytic degradation. Samples were harvested at designated time points up to 12 weeks and (1) prepared for scanning electron microscopy (SEM), (2) lyophilized and weighed, (3) mechanical properties determined using a servohydraulic Instron 8511, (4) dissolved and run on a SDS-PAGE gel, and (5) characterized with Fourier transform infrared spectroscopy. Control samples were incubated in phosphate-buffered saline. Fibroin was shown to proteolytically degrade with predictable rates of change in fibroin diameter, failure strength, cycles to failure, and mass. SEM indicated increasing fragmentation of individual fibroin filaments from protease-digested samples with time of exposure to the enzyme; particulate debris was present within 7 days of incubation. Gel electrophoresis indicated a decreasing amount of the silk 25 kDa light chain and a shift in the molecular weight of the heavy chain with increasing incubation time in protease. Results support that silk is a mechanically robust biomaterial with predictable long-term degradation characteristics.     

大鼠孤束迷走复合体儿茶酚胺能神经元向杏仁核的直接投射—HRP与免疫组织化学双标记研究

将HRP注入大鼠杏仁中央核(Ce)和基底外侧核(BL),发现在孤束迷走复合体(Sol/dmnx)尾段出现较多的逆行标记细胞。将WGA-HRP注入Sol/dmnx,在Ce和BL见到标记终末。用HRP逆行追踪和抗酪氨酸羟化酶(TH)抗体进行的免疫组化染色相结合的双重标记方法,发现从锥体交叉平面到最后区(AP)吻端平面,Sol/dmnx内有恒定的HRP逆行标记、TH样阳性和HRP/TH样双重标记的三种阳性神经元。双标记细胞主要分布于连合核(solC)、内侧亚核(solM),少量的位于间位核(solI)、背侧亚核(solD)及dmnx的背侧缘等。闩至最后区平面较多。阳性细胞皆以小型为主,多为圆形、三角形,soll中的则为长梭形。双重标记细胞占TH样免疫阳性细胞总数的18.8%,占HRP逆标细胞总数的90%,同侧为主,对侧偶见。本文对其功能意义作了探讨分析。     

中国北方人群系统性红斑狼疮患者KIR基因多态性的研究

目的:检测和分析系统性红斑狼疮患者的杀伤细胞免疫球蛋白样受体(KIR)基因的多态性, 探讨系统性红斑狼疮(SLE)从基因到临床表达的发病机制.方法:应用PCR-SSP技术检测北方62例确诊SLE患者和61例同一区域同一民族正常对照者的KIR基因位点多态性.结果:SLE 患者KIR基因表型分布较常见的为KIR3DP1、 2DL1、 2DP1、 3DL1、 2DL3及1D, 其次为2DS4、 2DL5、 3DS1、 2DS2、 2DS5和2DL2, 较低者为2DS1、 2DS3及3DP1V, SLE病例组KIR3DS1, 2DL2、 2DL5和2DL3基因型频率比对照组显著降低(P<0.01).结论:中国北方人群的SLE的发生可能与多个KIR基因等位基因有相关性.