Alterations of nitric oxide synthase in cardiac sarcoplasmic reticulum from rats with myocardial calcification

AIM: To study alterations of nitric oxide synthase (NOS) in cardiac sarcoplasmic reticulum from rats with myocardial calcification, and to explore the mechanism of inhibition of SR function in the rats with myocardial calcification. METHODS: Compared with control, myocardial calcium content in the 6 weeks increased by 408%（Ｐ＜0.01）, the NO production, NOS activity and NOS protein expression in the SR with myocardial calcification increased versus control（Ｐ＜0.01）.Myocardial calcium content was not alterations significantly, but the NOS/NO pathway in the SR was up-regulated slightly in the 2 weeks. RESULTS: Compared with control, myocardial calcium content in the 6 weeks increased by 408%(P＜0.01), the NO production, NOS activity and NOS protein expression in the SR with myocardial calcification increased versus control(P＜0.01).Myocardial calcium content was not alterations significantly, but the NOS/NO pathway in the SR was up-regulated slightly in the 2 weeks. CONCLUSION: The up-regulated NOS/NO system in the SR with myocardial calcification is the important mechanism of function inhibition of the SR.     

Effect of airway remodeling on airway responsiveness in asthmatic guinea pigs

AIM: To establish a guinea pig asthma model and to evaluate the effect of airway remodeling on airway responsiveness. METHODS: The guinea pig asthma model was established by ovalbumin (OVA) sensitization and challenge repeatedly. Bronchial provocation tests were conducted through intravenous injection of acetylcholine. The airway morphologic parameters were measured by computer image analysis system. White blood cells and the differential count in bronchoalveolar lavage fluid (BALF) were examined. RESULTS: The resistance of airway was increased significantly after 4 weeks of OVA exposure, but the increase disappeared upon prolonged exposure. After 8 weeks of OVA exposure, fiber tissue in large airway was increased, and the thickness of smooth muscle layer of small airway was enlarged, as compared with that in control animals. CONCLUSION: Airway responsiveness has changed after prolonged OVA exposure in guinea pigs. This change is related to airway remodeling.     

斜纹夜蛾抗菌物质的诱导及其理化特性

用大肠杆菌K12D31免疫斜纹夜蛾六龄幼虫，12h后收集血淋巴并通过高温处理制成粗提液。SDS-PAGE电泳结果表明：诱导后粗提液含有3条分别为43．5、15．0、4．0kD的特异性条带。诱导产生的抗菌物质在酸性、高温和常温等条件下保持稳定。抗菌谱测定结果表明，诱导产生的抗菌物质对猪霍乱沙门氏菌、枯草芽孢杆菌、铜绿假单胞菌等革兰氏阴性和阳性菌有抑制作用，而且对白色念珠球菌、酿酒酵母也有抑制作用。     

Celecoxib induces apoptosis in COX-2 non-expression gastric cancer cells

AIM: To investigate whether celecoxib induces gastric cancer cell apoptosis in a COX-2 non-expression cell line. METHODS: The COX-2 protein was examined by western blotting. Fluorescence microscopy, DNA agarose gel electrophoresis and flow cytometry analysis were used to test apoptosis. RESULTS: COX-2 was expressed in AGS but not MGC-803 gastric cancer cell line; Selective COX-2 inhibitor celecoxib induced MGC-803 cell line apoptosis in a concentration and time-dependent manner. CONCLUSION: Celecoxib induces apoptosis in COX-2 non-expression gastric cancer cells.     

Significance of expression of thrombospondin-1 and receptor-CD36 in hepatocellular carcinoma

AIM: To study the expression of thrombospondin-1 (TSP-1) and receptor-CD36, and investigate the relationship between tumor invasive capability and microvessel density and thrombospondin-1. METHODS: 43 hepatocellular carcinoma (HCC) cases were under investigation. Tissues from tumor, corresponding adjacent non-HCC tissue were stained with CD34 to show the MVD. TSP-1 and CD36 were examined by immunohistochemistry (SP) and RT-PCR. Relationship between clinical pathological features and above parameters was analyed. RESULTS: The staining of TSP-1 in HCC tissue is significantly lower than that in corresponding adjacent non-HCC tissue. Expression of TSP-1 was correlated to tumor thrombi, capsule, tumor invasive capability and CD36. CD36 was also correlated to tumor thrombi and tumor invasive capability. MVD was significantly higher in TSP-1, CD36 positive group than that in negative group. CONCLUSION: TSP-1 inhibits the growth, invasion and angiogenesis in HCC. TSP-1 may take effect through CD36.     

昆虫对Bt晶体蛋白杀虫作用的影响

本文概述了近年来昆虫肠液蛋白酶、中肠受体蛋白和昆虫抗性方面对苏云金杆菌杀虫晶体蛋白杀虫作用的影响。本期先刊登该文中的第一和第二部分。     

东莞莲花山自然保护区蝴蝶资源的研究

本文根据2001、2002年的调查结果，记述了东莞莲花山自然保护区的蝴蝶9科36属60种，分析了不同季节蝴蝶优势种的特点。结果表明，在2001年中以6月份的蝴蝶种类最多为34种，9月、4月、12月则分别为18、14、2种；全年中的优势种为报喜斑粉蝶Delias pasithoe(Linnaeus)、绢斑蝶Parantica aglea phormis(Fruhstorfer)、蓝点紫斑蝶Euploea midamus (Linnaeus)、巴黎翠凤蝶Papilio paris paris Linnaeus和宽边黄粉蝶Eurema hecabe(Lin-naeus)。     

非嗜食植物中的昆虫产卵驱避物及其利用

产卵是植物性昆虫生命周期中的一个重要环节，它能反映昆虫与植物相互作用的某些特点以及植食性昆虫对植物利用的策略。植物中的驱避物质在调节昆虫产卵行为过程中超着十分重要的作用。大量研究结果表明：许多非嗜食植物含有对昆虫产卵有驱避作用的次生化合物。研究植物中的昆虫产卵驱避物质不仅能在理论上加深对植食性昆虫产卵机制，植食性昆虫与植物间的相互关系以及昆虫群落构建机制等的认识，同时在害虫综合治理中有广泛的应用前景。     

黄土高原地区的生态建设与政策创新

生态环境建设是西部大开发的根本切入点。黄土高原地区是我国生态环境最为严峻的地区 ,目前仍有 2 9万 km2 的土地有待治理 ,任务十分艰巨。本区生态环境建设的主要阻力是生态系统脆弱、经济系统贫困、科技文化水平落后、生态建设效益滞后、投资巨大等。提出的对策是稳定落实“退田还林”补贴政策 ,完善多元化的生态建设投资体系 ,建立公平合理的资源开发政策体系 ,加强生态环境建设的科技支撑作用 ,严格控制人口的快速增长等。强调排除阻力、促进生态环境建设的关键是调整思路 ,在各项政策和措施上都有所创新 ,有所突破     

猪传染性胸膜肺炎放线杆菌apxIA基因在毕赤酵母中的表达与分析

构建猪传染性胸膜肺炎放线杆菌(APP)apxIA基因的真核表达载体pPICZαA/apxI,并在毕赤酵母GS115中进行表达。SDS-PAGE显示仅在浓缩40倍的上清中检测得到表达产物,同时经RT-PCR可检测到重组酵母中编码目的基因成熟肽的mRNA,经分析发现目的序列AT含量高达62%,其中含49个毕赤酵母稀有密码子,占15.4%。证实ApxIA在毕赤酵母中为低水平表达。