Protective effect of chronic caffeine intake on gene expression of brain derived neurotrophic factor signaling and the immunoreactivity of glial fibrillary acidic protein and Ki-67 in Alzheimer’s disease

Alzheimer’s disease (AD) is a neurodegenerative disorder with progressive degeneration of the hippocampal and cortical neurons. This study was designed to demonstrate the protective effect of caffeine on gene expression of brain derived neurotrophic factor (BDNF) and its receptor neural receptor protein-tyrosine kinase-β (TrkB) as well as glial fibrillary acidic protein (GFAP) and Ki-67 immunoreactivity in Aluminum chloride (AlCl₃) induced animal model of AD. Fifty adult rats included in this study were classified into 5 group (10 rats each); negative and positive control groups (I&II), AD model group (III), group treated with caffeine from the start of AD induction (IV) and group treated with caffeine two weeks before AD induction (V). Hippocampal tissue BDNF and its receptor (TrkB) gene expression by real time RT-PCR in addition to immunohistochemical study of GFAP and Ki67 immunoreactivity were performed for all rats in the study. The results of this study revealed that caffeine has protective effect through improving the histological and immunohistochemical findings induced by AlCl₃ as well as BDNF and its receptor gene expression. It could be concluded from the current study, that chronic caffeine consumption in a dose of 1.5 mg/kg body weight daily has a potentially good protective effect against AD.     

重组人粒细胞-巨噬细胞集落刺激因子乳酸链球菌表达载体的构建

目的:构建重组人粒细胞-巨噬细胞集落刺激因子乳酸链球菌表达载体,为进一步研究人粒细胞-巨噬细胞集落刺激因子在乳链菌的表达及其治疗价值奠定基础。方法:实验于2005-04/2006-03在南方医科大学南方医院消化病研究所完成。①载体pNCSF的构建:将质粒集落刺激因子及含有P59启动子、USP45蛋白信号肽的pNBC1000质粒分别加入BamH Ⅰ和Pst Ⅰ进行双酶切,并用Apa Ⅰ、Sac Ⅰ进行双酶切鉴定,重组质粒命名为pNCSF。②SDGFP的TA克隆及载体pNCSFGFP的构建:将经过优化适合在乳链菌表达的人粒细胞-巨噬细胞集落刺激因子基因克隆于含有P59启动子、USP45蛋白信号肽的pNBC1000载体,得到重组质粒pNCSF;同时设计上下游引物经PCR扩增增强荧光表达蛋白(EGFP),TA克隆后经测序验证,再连接于pNCSF获得重组质粒pNCSFGFP。③载体pTRCSF、pTRCSFGFP的建立:将获得的pNCSF和pNCSFGFP进一步克隆于穿梭载体pTR1001c,以获得人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP。结果:①载体pNCSF构建结果:酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子)720bp的目的片段。②SDGFP的TA克隆及载体pNCSFEGFP的构建结果:SDGFP阳性克隆产物经EcoRⅠ酶切鉴定得到775bp目的片段。pNCSFEGFP酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子、SDGFP)1495bp的目的片段。③穿梭质粒pTRCSF、pTRCSFGFP酶切鉴定结果:经Xba Ⅰ、Sac Ⅰ进行双酶切鉴定,分别得到约717bp、1492bp大小目的片段。结论:获得了人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP,并经酶切鉴定和测序证实。     

上海市0～6岁小儿佝偻病的现状调查

目的:了解上海市小儿佝偻病的现状及影响因素。方法:2005年春季以整群和分层随机抽样法抽取上海市部分城区0～6岁小儿821名,采取问卷调查方法了解小儿的生活环境、饮食习惯、户外活动、营养状况、既往疾病史及母亲的妊娠情况等。佝偻病的诊断以1996年国家卫生部颁布的"婴幼儿佝偻病防治方案"为诊断标准。结果:取得完整有效资料769名,其中男童396名,女童373名;集居儿童456名,散居儿童313名。①小儿佝偻病患病率为17.3%(133/769),其中男童患病率为17.4%、女童为17.2%。②佝偻病与喂养方式(母乳喂养的患病率为13.0%、混合喂养的患病率为17.5%、人工喂养的患病率为25.2%)、鱼肝油添加(按时添加维生素D的患病率为13.5%、偶加或未加维生素D的患病率为32.5%)、居住环境(居住在市区的患病率为23.6%、居住在郊区的患病率为10.6%;集居儿童患病率为13.8%、散居儿童患病率为22.4%)、户外活动时间(经常户外活动的患病率为12.9%、偶尔户外活动的患病率为31.8%)、反复呼吸道感染(小儿有反复呼吸道感染的患病率为26.9%、无反复呼吸道感染的患病率为12.9%)、母孕期缺钙(母孕期有缺钙的患病率为33.2%、无缺钙的患病率为12.0%)等因素有关(P<0.01)。结论:上海市小儿佝偻病患病率有上升趋势。影响因素与城市环境污染、母乳喂养减少、年轻父母科学育儿知识缺乏等有关。     

Valerenic acid derivatives as novel subunit-selective GABAA receptor ligands �Cin vitro and in vivo characterization

BACKGROUND AND PURPOSE

Subunit-specific modulators of γ-aminobutyric acid (GABA) type A (GABA_A) receptors can help to assess the physiological function of receptors with different subunit composition and also provide the basis for the development of new drugs. Valerenic acid (VA) was recently identified as a β_2/3 subunit-specific modulator of GABA_A receptors with anxiolytic potential. The aim of the present study was to generate VA derivatives as novel GABA_A receptor modulators and to gain insight into the structure–activity relation of this molecule.

EXPERIMENTAL APPROACH

The carboxyl group of VA was substituted by an uncharged amide or amides with different chain length. Modulation of GABA_A receptors composed of different subunit compositions by the VA derivatives was studied in Xenopus oocytes by means of the two-microelectrode voltage-clamp technique. Half-maximal stimulation of GABA-induced chloride currents (I_GABA) through GABA_A receptors (EC₅₀) and efficacies (maximal stimulation of I_GABA) were estimated. Anxiolytic activity of the VA derivatives was studied in mice, applying the elevated plus maze test.

KEY RESULTS

Valerenic acid amide (VA-A) displayed the highest efficacy (more than twofold greater I_GABA enhancement than VA) and highest potency (EC₅₀= 13.7 ± 2.3 µM) on α₁β₃ receptors. Higher efficacy and potency of VA-A were also observed on α₁β₂γ_2s and α₃β₃γ_2s receptors. Anxiolytic effects were most pronounced for VA-A.

CONCLUSIONS AND IMPLICATIONS

Valerenic acid derivatives with higher efficacy and affinity can be generated. Greater in vitro action of the amide derivative correlated with a more pronounced anxiolytic effect in vivo. The data give further confidence in targeting β₃ subunit containing GABA_A receptors for development of anxiolytics.     

Role of the signal peptide in the synthesis and processing of the glucagon-like peptide-1 receptor

Background and purpose:

The glucagon-like peptide-1 receptor (GLP-1R) belongs to Family B of the G protein-coupled receptor superfamily and is a target for treatment of type 2 diabetes. Family B G protein-coupled receptors contain a putative N-terminal signal peptide, but its role in receptor synthesis and trafficking are unclear. Further, the signal peptide is not cleaved in at least one family member.

Experimental approach:

We examined receptor glycosylation and the role of the signal peptide in GLP-1R synthesis and trafficking using constructs containing epitope tags at the N- and/or C-terminus and in which the signal peptide sequence was either present or absent.

Key results:

The signal peptide was absolutely required for GLP-1R synthesis but could be substituted to some extent by increasing positive charge in the N-terminal region of the receptor flanking the signal peptide. The signal peptide is cleaved during synthesis and processing of the receptor. An enhanced GFP-epitope tag at the N-terminus of the receptor permitted synthesis of the receptor but blocked signal peptide cleavage and prevented trafficking to the plasma membrane. Cleavage site mutation allowed synthesis of a full-length receptor, blocked signal peptide cleavage and caused retention within the endoplasmic reticulum.

Conclusions and implications:

Signal peptide cleavage was not essential for receptor synthesis but was obligatory for processing and trafficking of receptors to the plasma membrane. Further, the GLP-1R is subject to N-linked glycosylation and only the mature, fully glycosylated form of the receptor is present in the plasma membrane. Inhibition of glycosylation prevents processing and cell surface expression of the GLP-1R.     

紫外分光光度法测定复方酮康唑软膏中酮康唑和氧氟沙星的含量

目的：建立复方酮康唑软膏的含量测定方法。方法：用双波长分光光度法测定酮康唑的含量，用单波长法测定氧氟沙星的含量。结果：两被测组分的平均回收率和相对标准偏差分别为酮康唑１００．３３％和０．３２％；氧氟沙星１００．８５％和０．２７％。结论：方法简便、准确，可用于复方酮康唑软膏的质量控制。     

盐酸放线瑞香宁的紫外二阶导数光谱法测定及在兔体内的药代动力学

盐酸放线瑞香宁(actinodaphine-HCl)系从莲叶桐科青藤属植物黑吹风(Illigera khasiana C.B Clarke)中分离提取而得的有效成分,结构式如图1。药理试验证明有解热、镇痛、解痉等作用。本文报告用紫外二阶导数光谱法研究盐酸放线瑞香宁在兔体内的药代动力学结果。家兔4只,体重2.8±0.6kg。盐酸放线瑞香宁由本所植化室提供。氯仿、乙醇均为A.R。Perkin-Elmer型紫外—可见光分光光度计系美国产品。     

Cytotoxic potency and induced biochemical parameters in mice serum of new furan derivatives against liver cancer cell line

On the basis of monitoring the inhibition of the growth of human cancer cells, a series of novel furan derivatives of possessing a broader spectrum of antitumor activity and fewer toxic side effects than traditional anticancer drugs have been studied. Ten selected furan derivatives were subjected to a screening system for investigation of their antitumor potency against liver (HEPG2) cell line. Moreover, the biochemical effects of the selected furan derivatives on some enzymes such as aspartate and a lanine aminotransferases (ASTand ALT) and alkaline phosphatase (ALP), in addition to albumin, globulins, creatinine, total lipids, cholesterol, triglycerides and bilirubin in serum of mice were studied in comparison to 5-fluorouracil and doxorubicin. The antitumor activity results indicated that the selected furan derivatives showed growth of inhibition activity against the tested cell line but with varying intensities extents. Results of the biochemical investigations indicated that 5-fluorouracil and doxorubicin caused significant changes in the level of all parameters tested while treatment with the selected compounds showed slight, moderate or no significant changes.     

Mandibular stability and condylar changes following orthognathic surgery in mandibular hypoplasia patients associated with preoperative condylar resorption

Clinical Oral Investigations - To evaluate postoperative mandibular stability and condylar changes in patients with mandibular hypoplasia and preoperative condylar resorption (CR) undergoing...