温度和砷对不同品种水稻幼苗生长和砷吸收的影响

为明确温度和外源砷对水稻生长发育的影响,选取江苏地区常见的8个水稻品种为试验材料,通过添加不同浓度外源砷[0(As0)、0.5(As0.5) 和1 mg?L-1(As1)]和模拟不同温度[白天/夜晚分别为30 ℃/25 ℃（T0）和35 ℃/30 ℃（T1）],在人工气候箱内进行了发芽和苗期培养试验,并分析了8个品种水稻种子萌发、幼苗生长及砷含量状况。结果表明,外源砷对水稻的芽长和活力指数具有抑制作用,与对照（T0As0）相比,T0As1处理使不同品种水稻的芽长和活力指数分别降低13.69%~43.34%和28.14%~52.88%。 而温度对水稻种子萌发的影响与水稻品种有关。在T1处理下,盐两优1618的发芽率、芽长和活力指数均优于其他品种。温度和外源砷的共同作用显著降低了不同品种水稻的芽长（P<0.05）。与T0As0相比,T1As1使水稻芽长显著降低5.66%~43.34%。水稻根长和根系活力显著受到温度和外源砷的单一因素的影响。与T0As0相比,T0As1处理使水稻根系活力降低3.01%~58.21%。温度和外源砷的共同作用抑制了水稻根长和根系活力,其中T1As1使水稻根系活力显著降低53.80%~89.01%。不同品种水稻的苗高和根系活力在相同温度或外源砷处理下具有显著差异（P<0.05）,其中盐两优888的苗高和根系活力均处于较高水平。水稻茎叶砷含量在外源砷处理下显著增加,在增温处理下却降低。与单一的砷处理相比,温度和外源砷的共同作用降低了水稻茎叶的砷含量。综上可知,温度和外源砷影响水稻的生长及砷吸收,但水稻生长状况具有明显的品种间差异,其中盐两优888和盐两优1618在增温和外源砷共存条件下的种子萌发和生长状况优于其他水稻品种。     

60Co辐射诱变姬松茸突变株J3子实体不同部位的氨基酸分析研究

测定并比较了60Co辐射诱变姬松茸突变株J3与原菌株J1子实体不同部位的氨基酸含量.结果表明,除菌柄和盖皮外,姬松茸突变株J3子实体其它部位的必需氨基酸、儿童氨基酸、硫氨酸、支链氨基酸、鲜味氨基酸、芳香族氨基酸和甜味氨基酸均高于原菌株J1.姬松茸突变株J3子实体中谷氨酸含量占氨基酸总量的比例分别比原菌株J1、α-酪蛋白和卵清蛋白提高34.88%、56.68%和122.32%.     

Biological characteristics of long passaging rat mesenchymal stem cells

AIM:To investigate multi-potential of rat bone marrow mesenchymal stem cells (rBMMSC) and mutation inclination, the rBMMSC were long passaged in vitro. METHODS:Cellular cycles of different passages were assayed by FACSan flow cytometry and karyotypes of passage 6, passage 25 and passage 45 were compared by G-binding analysis. RESULTS:The early passages and long-term passages all showed strong proliferation; passage 6, passage 25 and passage 45 all showed normal karyotype. CONCLUSION:Long-term culture and passage of rBMMSC still remains strong proliferation. With this capability, the mutation inclination is not enhanced.     

Effects of FK506 on anti-glomerular basement membrane nephritis in rats

AIM:To investigate the effects of FK506 on anti-glomerular basement membrane(GBM) nephritis in rats. METHODS: Anti-GBM nephritis model was elaborated by rabbit anti-rat GBM antibody injection in SD rats in this study. The rats were divided into three groups: FK506 treated group(0.5 mg·kg^-1·d^-1, sc), untreated nephritis control group and normal control group. FK506 was administered daily six hours after injection of anti-GBM IgG. All the rats were observed urinary protein at the 4th day, the 14th day and the 21st day. At the same time, the kidney specimens were collected, and T cell transforming function was also monitored.RESULTS:Rats injected with rabbit anti-GBM Ab developed heavy proteinuria by 4 days, and serum creatinine and serum urea appeared which kept on the rising. Glmerular hypercellularity, crescents, and protein casts were observed in nephritic rats. By electron microscopy, the thickening of GBM and loss of foot processes were seen. T cell transforming function was higher than normal. But, all pathological changes obviously turned for the better in FK506 treated group. CONCLUSION:FK506 could inhibit the progression of rat anti-GBM nephritis.     

Expression of cyclooxygenase-2 in IL-1β-stimulated mesangial cells is medicated by NF-κB/IκB signal pathway

AIM: To investigate the role of NF-κB/IκB signal pathway in the regulation of cyclooxygenase-2 (COX-2) expression in human mesangial cells (HMC). METHODS: The PGE₂ concentration in supernatants of HMC was measured by radioimmunoassay. COX-2 mRNA and protein expression were determined by RT-PCR and Western blot. Electrophoretic mobility shift assay (EMSA) and Western blot were used to detect the activity of NF-κB and degradation of IκB. RESULTS: IL-1β significantly upregulated COX-2 expression and PGE₂ production in HMC. Significant up-regulation of NF-κB activation, nuclear translocation of p65 subunit, and degradation of IκB α and IκB β were observed in IL-1β-induced HMC. CONCLUSION: Expression of COX-2 in IL-1β-induced HMC is mediated by NF-κB/IκB signal pathway.     

Recent advances in molecular mechanisms of oncosis

Oncosis is another form of cell death, which is different from apoptosis. The review will discuss the recent advances of oncosis on pathological morphology, nuclear biochemical changes and molecular mechanisms.     

国内鹌鹑资源及其养殖现状和发展前景

介绍了关于野生鹌鹑遗传资源的种类、分布、迁徙规律以及被驯化后一些生活习性的改变和养殖现状,提出了我国在今后养殖鹌鹑产业中的机遇和挑战.     

opaR基因缺失对AHPND致病菌生物学特性及毒力质粒接合转移的影响

急性肝胰腺坏死病(acute hepatopancreatic necrosis disease, AHPND)严重影响了我国乃至全球对虾养殖业的发展。近期研究发现,致病菌毒力质粒携带trb型Ⅳ型分泌系统(type Ⅳ secretion system, T4SS)可在高菌体密度下介导毒力质粒发生接合转移,从而导致AHPND致病菌多样性。为探究群体感应与T4SS表达以及毒力质粒接合转移的关系,本研究以副溶血弧菌(Vibrio parahaemolyticus)群体感应系统的高密度调控子OpaR为研究对象,在致AHPND副溶血弧菌20130629002S01::cat(Vp2S01::cat)菌株基础上,利用同源重组技术构建opaR基因缺失株Vp2S01::catΔopaR。比较了出发菌株和缺失株在生长性能、运动性和生物被膜形成能力等方面的差异,分析了opaR基因对T4SS基因表达量以及质粒接合转移效率的影响。结果显示,opaR基因缺失不影响细菌的生长特性和群集运动,但泳动能力显著增加,生物被膜形成能力显著下降;接合转移实验显示,opaR基因缺失显著提高T4SS表达水平和接合转移效率。本研究为解析群体感应系统调控AHPND致病菌T4SS表达以及毒力质粒接合转移机制提供了基础数据,可为控制AHPND致病菌毒力质粒传播提供技术支撑。