牛副结核分枝杆菌实时荧光定量 PCR 检测方法的建立

根据GenBank上公布的牛副结核分枝杆菌C-2染色体的ISMav2基因保守区域序列设计合成1对特异性引物,建立了一套SYBR GreenⅠ荧光定量PCR检测牛副结核分枝杆菌(Mycobacterium paratuberculosis)的方法。以实验室构建的牛副结核分枝杆菌pMD-ISMav2阳性重组质粒为标准品,通过优化反应条件,建立了标准曲线,其相关系数为0.999。以构建的标准品为模板,进行了特异性和敏感性试验。结果显示,该方法检测布氏杆菌、大肠杆菌、沙门氏菌、链球菌DNA均为阴性;最低可检测到相当于每微升1.96×10¹拷贝数的标准品阳性质粒。本研究建立的实时荧光定量PCR具有特异、敏感和快速等优点,可用于牛副结核杆菌病的监测。     

秸秆施用后土壤溶解性有机质的动态变化

采用室内培养方法研究了水稻秸秆腐解对土壤溶解性有机质（Dissolved Organic Matter,DOM）含量及其化学组成的动态影响。结果表明,秸秆腐解的前7 d显著增加了土壤溶解性有机碳（DOC）含量,7 d后则无明显影响;同时,秸秆腐解增加了土壤中溶解性糖（DS）、溶解性酚酸（DP）以及芳香族化合物含量。随着腐解时间的延长,溶解性糖在DOC中所占比例下降,而芳香族化合物逐渐上升,表明秸秆腐解不同阶段DOM的化学组成发生了变化。溶解性总氮（TDN）的变化表明,秸秆腐解增加土壤氮素的固定。     

0505号超强台风“海棠”的特大暴雨落区诊断分析

准确预报台风暴雨对农业减灾有着非常重要的现实意义,本文针对0505号超强台风海棠登陆前后在温州地区南、北部有两个大降水落区,通过分析湿位涡的梯度分布、日本数值预报产品的要素场配置、东风急流与地形的关系等诊断大降水落区,指出：各要素的叠加区、湿位涡的梯度密集区、低层东风急流与地形正交抬升区均有利于大降水的发生,该结果对大降水的诊断预报有很好指示作用。     

RSM区域谱模式特征分析

短期气候的预测对农业生产、农业气象灾害的防御有重要作用。为探索短期气候预测的客观预报工具,引进美国NMC的区域谱模式RSM,并利用该模式对华东地区的短期气候要素进行了预测检验,结果显示：RSM区域模式在地形分布、台风结构、降水等方面的诠释能力较ECHAM4．5全球模式要好。     

Effect of L-arginine liposome on L-arginine transport of pulmonary artery in rats chronically exposed to hypoxia-hypercapnia

AIM: To investigate the effect of chronic hypoxia-hypercapnia and L-arginine (L-Arg) liposome on L-Arg transport in rats pulmonary artery. METHODS: Forty Sprague-Dawley rats were randomly divided into four groups, normal control group (NC), chronic hypoxia-hypercapnia group (HH), chronic hypoxia- hypercapnia group+L-Arg (HL) and chronic hypoxia-hypercapnia group+L-Arg liposome (HP). Changes in pulmonary artery L-Arg transport and pulmonary arterial microscopy were observed. RESULTS: (1) The mean pulmonary artery pressure (mPAP) and weight ratio of right ventricle to left ventricle and septum (RV/LV+S) in HH group were higher than those in NC group, and in HP group was lower than that in HH group and HL group, but there was no significant difference between HL group and HH group; (2) At 0.005 mmol/L, 0.01mmol/L, 0.02mmol/L, 0.05 mmol/L, 0.1 mmol/L and 0.2mmol/L concentration of L-Arg, the velocity of L-Arg transport in HH group was lower than that in NC group, and in HL group higher than in HH group, and in HP group was much higher than that in HH group and in HL group. (3) Light microscopy showed that vessel well area/total area (WA/TA) and media thickness of pulmonary arterioles (PAMT) were much higher in rats of HH group than those in NC group, WA/TA and PAMT in HP group were obviously improved. CONCLUSION: The above results indicated that there existed a functional disturbance in L-Arg transport of pulmonary artery in rats chronically exposed to hypoxia-hypercapnia, and it was obviously enhanced when liposome was used as L-Arg carrier. Thus, it appears that liposome-L-Arg may have clinical perspective in the treatment of chronic hypoxic pulmonary hypertension.     

Expression of MIP-1α and RANTES gene and protein in the bronchus of murine asthma

AIM: To study the role of the gene and protein expression of MIP-1α and RANTES in the bronchus of murine asthma. METHODS: 20 male BALB/C mice were randomly divided into two groups: the control group (A₀ group) and asthma group (B₀ group). In the experiment, the mice model of asthma was established by the ovalbumin (OVA) challenge methods. The protein expression of MIP-1α and RANTES were detected by immunohistochemistry methods. The gene expressions of MIP-1α and RANTES were detected by in situ hybridization methods. RESULTS: Immunohistochemistry showed that the expressions of MIP-1α protein and RANTES protein around the bronchus of group B₀ were significantly higher than those of group A₀ (P<0.01), the epithelial cells were the chief expression cells; (2) In situ hybridization showed that the expressions of MIP-1α gene and RANTES gene around the bronchus of group B₀ were significantly higher compared to those of group A₀ (P<0.01), the epithelial cells were the chief expression cells. CONCLUSION: MIP-1α and RANTES are high expression in the bronchus epithelial cells in experimental murine asthma.     

Protective effect of Ginkgo biloba extract on testicular tissue of diabetic rats

AIM: To investigate the protective effect of Ginkgo biloba extract (GBE) on diabetic testis and explore its possible mechanism. METHODS: Testicular structure of streptozotocin-induced diabetic rats was observed under light microscopy (LM) and transmission electron microscopy (TEM). Content of malondialdehyde (MDA), NO₂^-/NO₃^- and activity of superoxide dismutase (SOD), nitric oxide synthase (NOS) were determined in testicular homogenate. RESULTS: In diabetic rats, it was manifestated as deformation of seminiferous tubule, atrophy and shedding of germinal epithelium under LM, while expansion of smooth endoplasmic reticulum, formation of fatty vacuoles and decrease of lysosome obviously in the cytoplasm of sertoli cell under TEM, the injury of testicular tissue was improved by GBE. Compared with diabetic rats, activity of SOD increased while activity of tNOS and iNOS, content of MDA and NO₂^-/NO₃^- decreased in GBE-treated rats. CONCLUSION: GBE could effectively prevent the development of diabetic testis and the effect may be partly achieved by resisting lipid peroxidation,restraining the activity of testicular tissue iNOS and reducing the pathological alterations of NO.     

Mechanism underlying the antagonistic effect of folic acid on homocysteine-induced apoptosis in endothelial cell

AIM: To investigate the effects of homocysteine (Hcy) on apoptosis in SV40-transformed aortic rat endothelial cell line and the anti-apoptosis effects of folic acid. METHODS: Cells were treated with different concentrations of Hcy and folic acid, apoptosis was detected by TUNEL and annexin-V/ PI staining methods. Immunohistochemical assay was used to examine the expression of Bax and Bcl-2 in all groups. RESULTS: Both annexin-V/PI staining and TUNEL method showed that Hcy increased endothelial apoptosis in a dose-dependent manner, while folic acid reduced cell apoptosis. Hcy increased expression of Bax and Bcl-2 in endothelial cells, and folic acid decreased it. Bax/Bcl-2 ratio in 0.5 mmol/L Hcy and 5.0 mmol/L Hcy group were upregulated compared with control group (P<0.05 and P<0.01, respectively). Addition of 0.1 mmol/L folic acid decreased Bax/Bcl-2 ratio compared with the corresponding group without folic acid (P<0.05). Correlation analysis showed a strong relation between Bax/Bcl-2 ratio and apoptotic rate (P<0.01). CONCLUSION: Folic acid attenuates the apoptosis induced by Hcy in endothelial cells. Hcy may promote endothelial cell apoptosis via upregulation of Bax /Bcl-2 ratio, which can be partially antagonized by folic acid.     

新一代多普勒天气雷达在林火监测中的应用

对发生在浙江省温州和丽水地区6起森林火灾引起的雷达回波进行分析,发现新一代多普勒天气雷达的基本反射率、径向速度等产品对火灾烟气有明显的反映,雷达能对不同过火面积的火灾进行观测,火灾引起的回波具有水平尺度小、回波顶高度低、强度强等与地物回波相类似的特点,径向速度图上一般有辐散速度对.受较小风力和地形的影响,发生在大陆山区森林火灾的回波特征较海岛的更为显著.     

Therapeutic effect of 3TSR on gastric carcinoma in nude mice

AIM: To investigate the anti-tumor efficacy of angiogenic inhibitor three hrombospondin-1 type repeats (3TSR) on gastric cancer. METHODS: Human gastric carcinoma cell line SGC-7901 was inoculated subcutaneously to BALB/c mice, and then the mice were divided into two groups (8 mice each): control group and 3TSR group. After administration of 3TSR by intraperitoneal injection for 3 weeks, mice were sacrificed. The tumor volume and percentage of necrotic area were detected. The micro-vessel index and cell proliferation index were detected by immunohistochemistry method. The apoptosis rate of gastric carcinoma cells was measured by TUNEL method. The vascular endothelial cell apoptosis rates were detected by CD31/TUNEL/DAPI staining. RESULTS: The tumor volume in 3TSR group was (648.34±126.91)mm3, significantly lower than that in control group (P<0.05). The percentage of tumor necrosis area in 3TSR group was (39.6±7.8)%, almost increased by 69.2% than that in the control. Average micro-vessel numbers and micro-vessel area in 3TSR were 12.8±4.1 and (689.3±118.6) μm2, respectively, significantly lower than those in the control. The proliferation index and apoptosis rate in 3TSR group were (40.0±7.1)% and (3.4±1.2)%, respectively. No difference between 3TSR group and the control was observed. The endothelial cell apoptosis rate in 3TSR group was (11.6±2.8)%, significantly higher than that in control group (2.9±1.5)%. CONCLUSION: 3TSR inhibits tumor angiogenesis, remarkably reduces tumor volume, average micro-vessel and increased tumor necrosis. 3TSR shows no direct inhibitory effects on gastric cancer cells. The antiangiogenesis effects of 3TSR on gastric carcinoma may be due to the induction of apoptosis of vascular endothelia cells.