Protective effect of ischemic preconditioning on rat retina with sustaining ischemia

AIM: To observe the effect of ischemic preconditioning (IPC) on the subsequent permanent ischemic rat retina. METHODS: A model of two-vessel occlusion (2VO) was used to give an ischemic insult to rat retina. Bilateral carotid arteries were occluded directly in the simple ischemic groups. A procedure of double 2 min ischemia- 3 min reperfusion was applied to IPC groups before their carotid arteries were occluded. Experimental control groups received the same operation except that their exposed vessels were not occluded. Other 6 normal rats served as immunohistochemical controls. Eyeballs were taken out after being subjected to 1, 3 and 7 days of ischemia. The morphometry of retina was measured by stereologic methods. The apoptosis during the retinal ischemia was detected by TUNEL. Immunohistochemistry staining was used for the localization of bcl-2 in retina. RESULTS: In IPC groups, the thickness of retina was thinner than that in simple ischemic groups. The apoptosis was less when compared with the simple ischemic groups at the same ischemic time. The apoptotic cells show only in INL and the apoptosis of RGCs was not appeared until 7 days postischemia. There was no significant difference of the numerical density of RGCs at the different time after the operation. The bcl-2 immunoreactivity was weaker than that of the simple ischemic groups too. CONCLUSION: IPC reduced the injury caused by ischemia in retina, showing a protective effect.     

恒河猴甲状腺与甲状旁腺的组织学观察

应用光镜和透射电镜技术，探讨了2～15岁恒河猴甲状腺和甲状旁腺的细微结构。结果表明，甲状腺实质由滤泡和滤泡旁细胞构成。滤泡大小不等，平均直径173μm，由单层低立方上皮细胞围成，细胞平均高度4．93μm，胞质内含较丰富的细胞器和胶质小泡等。滤泡旁细胞较少，平均直径13．20μm，位于滤泡之间或镶嵌于滤泡上皮细胞之间，胞质内含少量的分泌颗粒。甲状旁腺位于甲状腺内，其实质由暗主细胞、淡主细胞、暗嗜酸性细胞、淡嗜酸性细胞组成，并可见腺泡样结构和脂肪细胞。主细胞平均直径6．96μm，嗜酸性细胞11．69μm。     

我国农业保险发展经营模式研究

我国农业灾害损失相当严重，农业保险是有效分散农业风险促进农业和农村经济发展的重要手段，针对我国实际国情，选择合适的农业保险发展模式十分重要。本文在分析了国内外各种农业保险发展模式的基础上，提出了我国农业保险发展模式。并对其进行了深入分析。     

亚洲璃眼蜱唾液腺-新基因（GP29）的原核表达及产物鉴定

将吸血诱导的亚洲璃眼蜱唾液腺差异表达基因GP29的开放性阅读框插入pGEX-4T-1，转化BL21，表达出一相对质量为53ku的蛋白，其大小与预计结果一致。蛋白质的肽质量图谱和“1381．7511”肽段序列两方面的结果证明，SDS-PAGE胶板上相对质量为53ku的蛋白就是由目的基因表达的GST融合蛋白。该蛋白与Swiss PROT库中的任何蛋白均有较大差别，可能是一个新功能分子。     

基因枪轰击注射鸭α-干扰素基因疫苗对免疫鸭抗鸭瘟强毒感染的影响

将鸭α-干扰素基因疫苗pcDNA-SDIFN-α分别按每只1、3和6μg剂量采用基因枪轰击方式免疫樱桃谷鸭,以PBS、空载体质粒pcDNA 3.1（＋）和鸭瘟弱毒疫苗为对照,注射后第15 d给每只鸭人工感染鸭瘟强毒.结果显示,1μg pcDNA-SDIFN-α免疫鸭有3/12死亡,PBS和空载体注射鸭分别有5/12和4/12死亡;3μg和6μg pcDNA-SDIFN-α免疫鸭以及鸭瘟弱毒疫苗免疫鸭100%受到保护.3个剂量pcDNA-SDIFN-α免疫鸭外周血鸭瘟病毒DNA含量显著低于PBS和空载体对照组,而3个pcDNA-SDIFN-aα免疫组之间差异不显著.表明,基因枪轰击pcDNA-SDIFN-α免疫鸭后能产生一定的抗鸭瘟强毒感染的作用.     

Genome-wide Association Study on Alive Litter Size Trait in Bama Xiang Pigs

In order to identify the molecular markers related to alive litter size of Bama Xiang pigs,the genome-wide association study (GWAS) was used to map and screen the candidate genes affecting the alive litter size trait.Ear tissue samples of 297 Bama Xiang pigs with multiple parity records were collected,and DNA was extracted and genotyped by porcine 50K SNP beadchip.After quality control and genotype imputation,the alive litter size of Bama Xiang pigs were GWAS by Tassel.The results showed that the average number born alive per litter of Bama Xiang pigs increased gradually with the increasing of parity in the range of 1-9 parities.A total of 32 816 SNPs were obtained after quality control and filtration.8 SNPs related to alive litter size of Bama Xiang pigs were screened by genome-wide association analysis,which were significant at genome or chromosome level.Based on the enrichment analysis of the coding genes in the region between 500 kb upstream and downstream of the associated significant SNP loci,and the QTL regions and gene functions related to porcine reproductive traits,4 genes (CAPZB,MSH3,CITED2 and HSD17B7) were finally identified to be candidate genes related to alive litter size of Bama Xiang pigs.     

he effects of constant magnetic field on apoptosis,adhesion molecule expression in endothelial cells and their adhesion rates with monocytes

AIM: To investigate the effects of constant magnetic field on apoptosis, secretion and expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVEC), and their adhesion rates with THP-1 monocytes induced by angiotensin Ⅱ (AngⅡ).METHODS: The third passage of cultured HUVEC was used.There were six groups: control group, Ang Ⅱ (10^-6 mol/L) group, Ang Ⅱ with 1, 5, 10 or 20 gausses of constant magnetic field group.Samples were collected 24 h after incubation with or without magnetic field.Apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and propidinm iodide staining with flow cytometry.Secretion and expression of ICAM-1 and VCAM-1 were detected by ELISA and immunocytochemistry, respectively.Adhesion rate between HUVEC and THP-1 was measured by counting method.RESULTS: Ang Ⅱ at concentration of 10^-6mol/L induced apoptosis in HUVECs (P<0.05 vs control), whereas in 1, 5, 10 and 20 gausses group, apoptosis of HUVECs was significantly lower than that in Ang Ⅱ group (P<0.05).Ang Ⅱ at concentration of 10-6 mol/L significantly increased secretion and expression of ICAM-1 and VCAM-1 (P<0.05 vs control), whereas secretion and expression of ICAM-1 and VCAM-1 in 1, 5, 10 and 20 gausses group significantly decreased, compared with Ang Ⅱ group (P<0.05).The adhesion rates between HUVEC and THP-1 significantly increased 24 h after incubation of HUVEC with Ang Ⅱ (P<0.05 vs control), in contrast, the adhesion rates between HUVEC and THP-1 in 1, 5, 10 and 20 gausses group significantly decreased, compaed with Ang Ⅱ group (P<0.05).CONCLUSIONS: One gauss to 20 gausses of constant magnetic field antagonizes the effects of Ang Ⅱ on HUVEC, decreases apoptosis and expression of ICAM-1 and VCAM-1 in HUVEC, and also decreases the adhesion rates between HUVEC and monocytes induced by Ang Ⅱ.     

Protective effects of ［Gly14］-humanin on cultured neural stem cells treated with β-amyloid protein in vitro

目的：研究［Gly14］-humanin对β淀粉样蛋白1-42引起的神经干细胞毒性的作用。方法：用［Gly14］-humanin和β淀粉样蛋白1-42处理神经干细胞，观察其对神经干细胞增殖、分化的影响。结果：较低浓度的［Gly14］-humanin加入有β淀粉样蛋白1-42处理的神经干细胞培养基，经过琼脂糖凝胶电泳分析及流式细胞测定DNA含量，神经干细胞显示出对β淀粉样蛋白1-42的耐受，而对照组则显示神经干细胞出现凋亡现象。高浓度的［Gly14］-humanin加入培养基，经台盼蓝拒染法计数细胞，神经干细胞死亡率明显低于对照组，对照组神经干细胞出现大量死亡。结论：［Gly14］-humanin 不但具有抑制β淀粉样蛋白1-42对神经干细胞的毒性作用，而且在低浓度的情况下，可以促进神经干细胞的增殖和分化为神经元。     

中国锦紫苏类病毒的检测及其分子生物学特征研究

 从无明显症状表现的11株锦紫苏叶片中抽提低分子量的RNA,经Return-PAGE、RT-PCR和Dot-blot hybridization检测,结果表明11株锦紫苏全部带有锦紫苏类病毒(Coleus blumei viroid,CBVd)。将部分PCR产物克隆到pGEM-3Zf(+)载体上并进行DNA序列测定。序列分析结果,所克隆的序列(GenBank登录号分别为DQ178395、DQ178396、DQ178397、DQ178398和DQ178399)与GenBank中报道的锦紫苏类病毒1号(CBVd-1)序列同源性为85.23%~99.20%。从市场上购买的锦紫苏种子经Return-PAGE和RT-PCR检测不携带锦紫苏类病毒。这是中国发生的锦紫苏类病毒的首次报道。