Changes in microtubule-associated protein-2 (MAP2) expression during development and after status epilepticus in the immature rat hippocampus

In this study, we analyzed the spatiotemporal expression patterns of the high-molecular weight (MAP2a and b) and low-molecular weight (MAP2c and d) cytoskeletal microtubule-associated protein-2 (MAP2) isoforms with Western blotting, and the cellular localization of the high-molecular weight MAP2 isoforms with immunocytochemistry in the hippocampi of 1- to 21-day-old rats. Moreover, the temporal profile (from 30 min to 1 week) of MAP2 isoform reactivity to kainic acid-induced status epilepticus was studied in P9 rats. During development, the expression of the high-molecular weight MAP2 isoforms significantly increased, while the low-molecular weight isoforms decreased, the most prominent changes occurring during the second postnatal week. This developmental increase in the high-molecular weight MAP2 expression was also confirmed with immunocytochemistry, which showed increased immunoreactivity, particularly in the molecular layers of the dentate gyrus, and in CA1 and CA3 stratum radiatum. In 9-day-old rats, status epilepticus resulted in a rapid transient increase (about 210%) in the high-molecular weight MAP2 expression, without any effect on the low-molecular weight MAP2. Moreover, disturbed dendritic structure in the CA1 and CA3 stratum radiatum was manifested as formation of varicosities 3h after the kainic acid treatment. The strictly developmentally regulated MAP2 isoform expression suggests different functional roles for these proteins during the postnatal development in the rat hippocampus. Moreover, high-molecular weight MAP2s may play a role in nerve cell survival during cell stress.     

Glucose deprivation depolarizes plasma membrane of cultured astrocytes and collapses transmembrane potassium and glutamate gradients

Primary cultures of astrocytes were used to investigate the effects of glucose deprivation on plasma membrane potential, on the respiration and on the energy status of these cells. Plasma membrane potential, as monitored with a cyanine dye, 3,3'-diethylthiadicarbocyanine, hyperpolarized by about 100% when glucose was added to substrate-deprived cells. The effect of glucose was prevented by iodoacetate or ouabain. In the absence of glucose, cellular adenosine triphosphate/adenosine diphosphate ratio was extensively reduced and pyruvate was unable either to restore energy status or to hyperpolarize the plasma membrane of astrocytes, although it was the preferential substrate for mitochondria within the cells. Glucose deprivation and inhibition of glycolysis or respiration in the presence of glucose caused dramatic decrease in transmembrane potassium ion and L-glutamate gradients. The gradients were not restored in the presence of pyruvate. Thus, aerobic glycolysis, rather than oxidation of pyruvate, is required to maintain maximal plasma membrane potential, adenosine triphosphate/adenosine diphosphate ratios as well as K+ and L-glutamate gradients. This evidence, together with the unresponsiveness of astrocyte respiration to ouabain, indicates a functional dissociation between energy dissipation at the plasma membrane and mitochondrial synthesis of adenosine triphosphate. The results are discussed with regard to the vulnerability of glia at low levels of blood glucose and the contribution of glial dysfunction to development of hypoglycaemic encephalopathy.     

Determination of GABA receptor-linked Cl- fluxes in rat cerebellar granule cells using a fluorescent probe SPQ

Gamma-Aminobutyric acid (GABA)-induced Cl- fluxes in cultured rat cerebellar granule cells were measured using the chloride-sensitive fluorescent probe SPQ (6-methoxy-N-(3-sulphopropyl)quinolinium) incorporated into the cells. The fluorescence of SPQ is quenched by Cl-ions. GABA and pentobarbitone increased the fluorescence of the probe when the Cl- gradient was directed outward by bathing cells, grown in the presence of GABA, in a low Cl- medium. Picrotoxin and bicuculline inhibited the response to GABA. The results suggest that SPQ is a suitable probe for measuring GABA-induced Cl- fluxes in living cells.     

真核表达人呼吸道合胞病毒F蛋白的纯化方法

目的 真核表达人呼吸道合胞病毒(human respiratory syncytial virus,SV)融合蛋白(fusion protein,),并完成蛋白纯化及纯度测定.方法 根据编码F蛋白的基因序列设计引物,CR方法扩增出3'端带His标签的F基因序列,克隆入pGEM-T-easy载体,经核酸序列分析后,进一步克隆到pcDNA3.1( )真核表达载体,限制性内切酶鉴定,用脂质体Lipofectamine2000转染COS-7细胞,2 h后再用Westem blot检测目的蛋白的表达.Ni柱亲和层析纯化COS-7细胞表达的F蛋白,高效毛细管电泳分析纯化后蛋白纯度.结果 核酸序列分析证实获得带His标签的RSV F基因序列,没有发生无义突变.转染COS-7细胞后,利用Western blot方法检测到F蛋白的特异性条带,纯度达99%以上.结论 初步建立了真核表达RSV F蛋白的纯化方法,为进一步优化RSV F蛋白制备条件及单克隆抗体及诊断试剂等研究奠定了基础.     

激素治疗增加绝经后健康妇女尿失禁的发病率和严重程度

问题：在绝经后健康妇女中，激素治疗（hormone therapy，HT）对尿失禁（urinary incontinence，UI）的效果如何？     

上皮样血管瘤16例临床与病理分析

 目的:探讨上皮样血管瘤（EH）的临床及组织病理学特征。 方法:回顾性分析16例已确诊患者的临床及病理资料,并对相关文献进行综述。 结果:16例患者中女8例,男8例;平均年龄（45.44±12.52）岁;病程3个月~20年;皮损主要表现为红色至暗红色丘疹、结节,可伴瘙痒和糜烂,好发于头皮、耳部,其中发生在头部10例、耳部5例、外阴1例;皮损单发者5例,多发者11例。皮损组织病理学检查均具有典型的血管增生,管壁增厚,内皮细胞呈上皮样突向管腔,管周大量淋巴细胞及嗜酸性粒细胞浸润。结论：上皮样血管瘤少见,诊断需要临床与病理密切结合。加强对该病的认识,可避免误诊误治。