冬小麦根表面氧化还原活力的研究

证实了两个不同品种的冬小麦根系表面存在着氧化ＮＡＤＨ和还原Ｋ３Ｆｅ（ＣＮ）６的氧化的活力。还原铁氰化物活力在ＰＨ５．５到８．５范围内随着ＰＨ值升高而增大,温度在１５℃到４５℃范围内随温度升高还原活力增强,４５℃达最高值,５５℃时活力急剧下降。     

贵州省腹袋属一新种记述(吸虫纲:同盘科)

本文记述寄生于贵州省丹寨县水牛瘤胃内同盘科腹袋亚科腹袋属内吸虫的一个新种,巨盘腹袋吸虫Gastrothylaxmagnadiscussp．nov.,简述了该属的简史,并将新种与该属已有的种类的主要特征列表进行了比较。     

In Vitro Reconstitution of Cortical Actin Assembly Sites in Budding Yeast

We have developed a biochemical approach for identifying the components of cortical actin assembly sites in polarized yeast cells, based on a permeabilized cell assay that we established for actin assembly in vitro. Previous analysis indicated that an activity associated with the cell cortex promotes actin polymerization in the bud. After inactivation by a chemical treatment, this activity can be reconstituted back to the permeabilized cells from a cytoplasmic extract. Fractionation of the extract revealed that the reconstitution depends on two sequentially acting protein factors. Bee1, a cortical actin cytoskeletal protein with sequence homology to Wiskott-Aldrich syndrome protein, is required for the first step of the reconstitution. This finding, together with the severe defects in actin organization associated with the bee1 null mutation, indicates that Bee1 protein plays a direct role in controlling actin polymerization at the cell cortex. The factor that acts in the second step of the reconstitution has been identified by conventional chromatography. It is composed of a novel protein, Pca1. Sequence analysis suggests that Pca1 has the potential to interact with SH3 domain-containing proteins and phospholipids.     

我国青藏区细蚤属一新亚种记述(蚤目:细蚤科)

在整理采自四川、青海的蚤类标本中,发现一新亚种,现记述如下: 栉头细蚤腹凹亚种Leptopsylla(Pectinoctenus) pectiniceps ventrisinulata新亚种 鉴别特征 本新亚种与指名亚种L.(P.) pectiniceps pectiniceps(Wagner, 1893)的主要区别有:(1)♂可动突后缘的近基2/3段较圆凹,其最宽的位置稍高;(2)抱器不动突     

The Hyper-Gene Conversion Hpr5-1 Mutation of Saccharomyces Cerevisiae Is an Allele of the Srs2/Radh Gene

The HPR5 gene has been defined by the mutation hpr5-1 that results in an increased rate of gene conversion. This mutation suppresses the UV sensitive phenotype of rad18 mutations in hpr5-1 rad18 double mutants by channeling the aborted repair events into a recombination repair pathway. The HPR5 gene has been cloned and is shown to be allelic to the SRS2/RADH gene, a putative DNA helicase. The HPR5 gene, which is nonessential, is tightly linked to the ARG3 locus chromosome X. The hpr5-1 allele contains missense mutation in the putative ATP binding domain. A comparison of the recombination properties of the hpr5-1 allele and the null allele suggests that recombination events in hpr5 defective strains can be generated by several mechanisms. We propose that the HPR5 gene functions in the RAD6 repair pathway.     

Structural and functional relationships of human DNA polymerases

A continuing theme of our laboraory, has been the understanding of human DNA polymerases at the structural level. We have purified DNA polymerases delta, epsilon and alpha from human placenta. Monoclonal antibodies to these polymerases were isolated and used as tools to study their immunochemical relationships. These studies have shown that while DNA polymerases delta, epsilon and alpha are discrete protiens, they must share common structural features by virtue of the ability of several of our monoclonal antibodies to exhibit cross-reactivity. A second approach we have taken is the molecular cloning of human DNA polymerase delta and epsilon. We have cloned the DNA polymerase delta cDNA, and this has allowed us to compare its primary structure to those of human polymerase alpha and other members of this polymerase family. Multiple sequence alignments have revealed that human DNA polymerase delta is also closely related to the herpes virus family of DNA polymerases. In situ hybridization has shown that the human DNA polymerase delta gene is localized to chromosome 19 q13.3–q13.4. In order to further determine the functional regions of the DNA polymerase δ structure we are currently expressing human pol δ inE. coli and baculovirus systems. Other work in our laboratory is directed toward examining the expression of DNA polymerase δ during the cell cycle.     

Enhanced Orai1-mediated store-operated Ca2+ channel/calpain signaling contributes to high glucose-induced podocyte injury

Podocyte injury induced by hyperglycemia is the main cause of kidney dysfunction in diabetic nephropathy. However, the underlying mechanism is unclear. Store-operated Ca²⁺ entry (SOCE) regulates a diversity of cellular processes in a variety of cell types. Calpain, a Ca²⁺-dependent cysteine protease, was recently shown to be involved in podocyte injury. In the present study, we sought to determine whether increased SOCE contributed to high glucose (HG)–induced podocyte injury through activation of the calpain pathway. In cultured human podocytes, whole-cell patch clamp indicated the presence of functional store-operated Ca²⁺ channels, which are composed of Orai1 proteins and mediate SOCE. Western blots showed that HG treatment increased the protein abundance of Orai1 in a dose-dependent manner. Consistently, calcium imaging experiments revealed that SOCE was significantly enhanced in podocytes following HG treatment. Furthermore, HG treatment caused overt podocyte F-actin disorganization as well as a significant decrease in nephrin protein abundance, both of which are indications of podocyte injury. These podocyte injury responses were significantly blunted by both pharmacological inhibition of Orai1 using the small molecule inhibitor BTP2 or by genetic deletion of Orai1 using CRISPR-Cas9 lentivirus. Moreover, activation of SOCE by thapsigargin, an inhibitor of Ca²⁺ pump on the endoplasmic/sarcoplasmic reticulum membrane, significantly increased the activity of calpain, which was inhibited by BTP2. Finally, the calpain-1/calpain-2 inhibitor calpeptin significantly blunted the nephrin protein reduction induced by HG treatment. Taken together, our results suggest that enhanced signaling via an Orai1/SOCE/Calpain axis contributes to HG-induced podocyte injury.     

基于遥感的建筑物高度快速提取研究综述

近年来我国城市化进程不断推进,不仅体现在城市面积上的增长,也体现在建筑物高度的增长。高度增长一方面能尽量克服城市土地资源匮乏的瓶颈,另一方面为优化城市结构及城市功能做出贡献。在城市遥感研究领域,对于城市建筑物高度的提取也成为研究的重点。城市建筑物高度的估计与测量,已成为城市规划和扩张、城市灾害风险预警与评估的重要参数,同时也为数字城市三维模型的建立提供了基础测绘资料。分别基于光学遥感影像、高分辨率SAR(Synthetic Aperture Radar)影像以及光学遥感影像与高分辨率SAR影像的融合三方面,全面阐述城市建筑物高度的提取方法,并比较两类影像在提取建筑物高度的优劣势,通过回顾早年研究方法,逐步引入近年来新的发展趋势。     

一株脱色真菌的鉴定及脱色特性的初步探讨

从废水环境中分离筛选到一株高效染料脱色真菌, 根据形态学及显微特征初步鉴定为泡盛曲霉(Aspergillus awamori), 命名为Asaw117; 从偶氮类、蒽醌类和氧醌类中选取8种不同染料进行脱色分析表明, 该菌株对0.1 g/L蒽醌类染料还原蓝RSN的脱色率可达100%; 采用不同培养基及不同种类碳氮源进行试验比较, 菌株在查氏培养基中生长慢, 但脱色效果最好, 在马铃薯培养基中生长旺盛, 脱色效果次之。此外, 菌株Asaw117能利用还原蓝RSN作为氮源, 但不能利用其为碳源; 几种碳氮源组合实验中, 菌株在蔗糖、硝酸铵组合的査氏培养基脱色效果为好。因此对处理印染废水具有较好的应用潜力。     

NaCl胁迫对小黄花菜生长及相关生理指标的影响

为探讨小黄花菜的耐盐机理,选育良好的耐盐植物以缓解土壤盐渍化问题,该文选取小黄花菜(Hemerocallis minor)为试材,采用砂培法,研究不同浓度NaCl(50、100、150、200、250 mmol·L-1)胁迫对小黄花菜的生长性状、细胞质膜透性和有机渗透调节物质含量等的影响.结果表明:(1)小黄花菜在10...