半导体激光辐照对花生种子活力的影响

采用３５０ｎｗ,８１０ｎｍ近红外光导体激光辐照花生干种子,经激光辐照后,种子胚根生长速度加快,胚根长度增加,侧根数目增加,种子出苗率提高。幼苗苗鲜重与根鲜重指标均高于对照组。实验证明,适当剂量的近红外半导体激光辐照可提高花生种子活力,促进幼苗生长。     

Proteomic analysis of hepatitis B virus-associated hepatocellular carcinoma: Identification of potential tumor markers

Hepatocellular carcinoma (HCC) is a malignancy of both underdeveloped and developing countries. Proteomes of ten pairs of clinical hepatitis B virus associated HCC tissue samples were obtained by high resolution two-dimensional gel electrophoresis. Comprehensive analyses of proteins associated with B-type HCC were focused on total differentially expressed proteins (> or = two-fold increase or decrease, Student's t-test, p < 0.05) from one pair of samples. Protein identification was done by peptide mass fingerprinting with matrix assisted laser desorption/ionization-time of flight mass spectrometry and liquid chromatography-tandem mass spectrometry. Comparative analyses of proteins associated with B-type HCC included repeat statistics in ten cases. A total of 100 protein spots, corresponding to 80 different gene products, were identified. Proteins whose expression levels were different by more than 2-fold in at least 50% of the cases (five of ten cases) were further analyzed and 45 proteins were selected out as candidates for HCC-associated proteins. Western blotting further validated up-regulated expressions of two candidate proteins in tumor tissues: proliferating cell antigen and stathmin 1. This comprehensive and comparative analyses of proteins associated with B-type HCC could provide useful molecular markers for diagnostics and prognostics and for therapeutic targets. The physiological significance of the differential expressions for several candidate proteins are discussed.     

Genomic constitution and taxonomy of the Chinese hexaploids Elymus cylindricus and E. breviaristatus (Poaceae: Triticeae)

Elymus cylindricus (2n = 6x = 42) and E. breviaristatus (2n = 6x = 42) are distributed in grasslands and deserts of northern and north‐western China. Their genomic constitution and taxonomic status are unclear. Elymus cylindricus was crossed with E. wawawaiensis J.R.Carlson & Barkworth ( StH ), Roegneria grandis Keng ( StY ) and Campeiostachys dahurica (Turcz. ex Griseb.) B.R.Baum, J.L. Y ang & C. Y en var. dahurica ( StYH ). Meiotic pairing in the hybrids E. cylindricus × E. wawawaiensis ( StH ), E. cylindricus × R. grandis ( StY ) and E. cylindricus × C. dahurica var. dahurica ( StYH ) showed on average 10.00, 11.30 and 20.92 bivalents per cell, respectively. Elymus breviaristatus was crossed with C. dahurica var. dahurica ( StYH ) and E. cylindricus. Chromosome pairing in the hybrids of E. breviaristatus × C. dahurica var. dahurica and E. breviaristatus × E. cylindricus showed on average 19.60 and 19.27 bivalents, respectively. Genomic in situ hybridization (GI SH ) revealed the presence of St , Y and H genomes in E. cylindricus and E. breviaristatus. An intergenomic rearrangement was observed in E. cylindricus using GI SH . Meiotic pairing data and GI SH indicated that both E. cylindricus and E. breviaristatus are allohexaploids containing the StYH genomes. Elymus cylindricus and E. breviaristatus should be treated as Campeiostachys dahurica var. cylindrica and Campeiostachys breviaristata, respectively.     

澜沧江流域暴雨干旱灾害与海温异常波动规律的相关性

基于中国气象局国家气象信息中心提供的澜沧江区域1961—2011年50年气象资料,采用EMD(Empirical Mode Decomposition)分解、均生函数逐步回归模型、相关分析等方法,探讨了澜沧江流域极端天气灾害的变化特征,及其区域极端灾害变化和全球海温异常ENSO(El Nio/La Nia-Southern Oscillation)之间的联系。结果表明:(1)该区域降水和暴雨频次存在多尺度特征,降水量存在2a、7a、15a的变化周期,且主周期为准2 a。(2)降水量和暴雨频度序列的IMF1和IMF2周期在2—7 a之间,与ENSO在年际变化上的信号相吻合,NINO(El Nio)指数无论春夏秋冬或年际都与暴雨和干旱灾害频次呈现负相关,而SOI(Southern Oscillation Index)指数则呈现正相关,其中,NINO指数与干旱相关性指数在秋冬和年际接近-0.3。(3)澜沧江流域暴雨和干旱灾害与ENSO有重要联系,且随着气温升高干旱灾害频次明显增加。研究结果显示区域极端气温灾害的变化与全球气候变暖有某种关联,是全球气候变化的区域响应表现形式之一。     

微生物生物技术处理气态污染物的研究进展

近年来大气污染问题愈发突出,工业生产过程是大气污染的一重要源头。微生物法治理制造工业生产中产生的挥发性有机物、恶臭气体、硫化物、氮氧化物等气态污染物以效率高、投资少、绿色且环境友好等优势逐渐在国内兴起,广受关注。本文综述了微生物法的基本理论、技术分类及特点、应用范围,以及国内外较新的研究方向与进展。微生物法净化低浓度污染物效率往往很高,而处理难溶、高浓度、生物毒性、难降解的污染物时易受到局限。专家学者们对此进行了大量研究与实验,创新出的高效技术进行总结。本文认为减少传质阻力方法的应用、与其他处理技术联用、清晰微生物降解机理与途径等是提高微生物法效率的重要方向。但提及的大部分强化手段仍处于实验研究阶段,使其工业化仍需要进一步探索。     

Bcl-2在去甲二氢愈创木酸诱导恶性胶质瘤细胞凋亡中的变化

观察bcl-2在去甲二氢愈创木酸（NDGA）诱导恶性胶质瘤细胞系SHG-44细胞凋亡中的变化。利用光镜和电镜观察及TUNEL法检测培养细胞凋亡的情况。用免疫组织化学,原位杂交和图像分析等方法检测bcl-2基因mRNA和蛋白的表达水平。结果显示：（1）一定浓度的NDGA处理SHG-44细胞12-96h,均可诱导SHG-44细胞发生凋亡,且随着作用时间的延长,凋亡细胞数增加越明显;（2）免疫组织化学方法结果显示,NDGA处理细胞后,出现SHG-44细胞bcl-2蛋白表达水平降低,且随着作用时间的延长,这种趋势更加明显,与细胞凋亡的发生密切相关;（3）原位杂交结果显示,NDGA处理细胞不同时间后,出现SHG-44细胞bcl-2基因mRNA的表达水平降低,结果与免疫组织化学方法检测结果一致,上述结果表明,NDGA诱导SHG-44细胞凋亡过程中,bcl-2基因的表达降低,但其确切机制有待进一步深入研究。     

Expression and localization of Muc4/sialomucin complex (SMC) in the adult and developing rat intestine: implications for Muc4/SMC function

Muc4/sialomucin complex (SMC) is a high molecular mass heterodimeric membrane mucin, encoded by a single gene, and originally discovered in a highly metastatic ascites rat mammary adenocarcinoma. Subsequent studies have shown that it is a prominent component of many accessible and vulnerable epithelia, including the gastrointestinal tract. Immunoblot and immunofluorescence analyses demonstrated that Muc4/SMC expression in the rat small intestine increases from proximal to distal regions and is located predominantly in cells at the base of the crypts. These cells were postulated to be Paneth cells, based on their location, morphology, and secretory granule content. Immunohistochemistry indicated the presence of Muc4/SMC in these granules. Muc4/SMC expression was higher in the rat colon than small intestine and was abundantly present in colonic goblet cells, but not in goblet cells in the small intestine. Immunohistochemistry also suggested the presence of MUC4 in human colonic goblet cells. Biochemical analyses indicated that rat colonic Muc4/SMC is primarily the soluble form of the membrane mucin. Analyses of Muc4/SMC during development of the rat gastrointestinal tract showed its appearance at embryonic day 14 of the esophagus and at day 15 at the surface of the undifferentiated stratified epithelium at the gastroduodenal junction, then later at cell surfaces in the more distal regions of the differentiated epithelium of the small intestine, culminating in expression as an intracellular form in the crypts of the small intestine at about day 21. Limited expression in the colon was observed during development before birth at cell surfaces, with expression as an intracellular form in the goblet cells arising during the second week after birth. These results suggest that membrane mucin Muc4/SMC serves different functions during development of the intestine in the rat, but is primarily a secreted product in the adult animal.