Podocyte-Related Mechanisms Underlying Survival Benefit of Long-Term Angiotensin Receptor Blocker

We previously found that short-term treatment (week 8 to 12 after injury) with high-dose angiotensin receptor blocker (ARB) induced the regression of existing glomerulosclerosis in 5/6 nephrectomy rats. We therefore assessed the effects of long-term intervention with ARB vs. nonspecific antihypertensives in this study. Adult rats underwent 5/6 nephrectomy and renal biopsy 8 weeks later. The rats were then divided into three groups with equivalent renal function and glomerular sclerosis and treated with high-dose losartan (ARB), nonspecific antihypertensive triple-therapy (TRX), or left untreated (Control) until week 30. We found that blood pressure, serum creatinine levels, and glomerulosclerosis were lower at sacrifice in ARB and TRX vs. Control. Only ARB reduced proteinuria and maintained the density of WT-1-positive podocytes. Glomerular tufts showed more double-positive cells for CD44, a marker of activated parietal epithelial cells, and synaptopodin after ARB vs. TRX or Control. ARB treatment reduced aldosterone levels. ARB-treated rats had significantly improved survival when compared with TRX or Control. We conclude that both long-term ARB and triple-therapy ameliorate progression, but do not sustain the regression of glomerulosclerosis. ARB resulted in the superior preservation of podocyte integrity and decreased proteinuria and aldosterone, linked to increased survival in the uremic environment.     

纳米酶在食品保鲜中的应用

具有优异广谱抗菌特性的纳米酶,为解决由微生物引起的食品腐败问题提供了一种全新策略。纳米酶可在生理环境中催化相应的底物而产生活性氧,因其制备简便、成本低、催化效率高,易于规模化生产和稳定性高等优点,故在食品保鲜领域具有广阔的应用前景。本文综述纳米酶的分类,包括金属或金属氧化物基纳米酶、碳基纳米酶、聚合物基纳米酶及其它材料,调控纳米酶抗菌活性的主要因素(大小、形态、涂层及改性、组成成分等),为如何设计高效抗菌纳米酶提供了参考。本文还阐述纳米酶在食品保鲜中的应用,包括纳米酶基抗菌薄膜应用及其在检测食品中细菌污染水平中的应用。由于其广谱抗菌特性和可忽略的生物毒性,抗菌纳米酶能降低食品工业中微生物的危害,而且有助于控制食品生产及加工中的交叉污染问题,对保障食品安全,促进食品工业健康可持续发展具有十分重要的现实意义。总而言之,抗菌纳米酶有望成为一种新型的抗菌剂和/或策略,在食品保鲜中展现出广阔的应用前景。     

Integrated Analysis of Microarray,Small RNA,and Degradome Datasets Uncovers the Role of MicroRNAs in Temperature-Sensitive Genic Male Sterility in Wheat

Temperature-sensitive genic male sterile (TGMS) line Beijing Sterility 366 (BS366) has been utilized in hybrid breeding for a long time, but the molecular mechanism underlying male sterility remains unclear. Expression arrays, small RNA, and degradome sequencing were used in this study to explore the potential role of miRNA in the cold-induced male sterility of BS366. Microspore observation showed defective cell plates in dyads and tetrads and shrunken microspores at the vacuolated stage. Differential regulation of Golgi vesicle transport, phragmoplast formation, sporopollenin biosynthesis, pollen exine formation, and lipid metabolism were observed between cold and control conditions. Pollen development was significantly represented in the 352 antagonistic miRNA-target pairs in the integrated analysis of miRNA and mRNA profiles. The specific cleavage of ARF17 and TIR1 by miR160 and miR393 were found in the cold-treated BS366 degradome, respectively. Thus, the cold-mediated miRNAs impaired cell plate formation through repression of Golgi vesicle transport and phragmoplast formation. The repressed expression of ARF17 and TIR1 impaired pollen exine formation. The results of this study will contribute to our understanding of the roles of miRNAs in male sterility in wheat.     

极大节旋藻(Arthrospira maxima)生物钟基因kaiC的克隆及分析

以kaiC基因簇部分已知序列为引物设计位点,采用PCR反应池法从节旋藻基因组fosmid文库中筛选到kaiC基因克隆,通过步移测序获得了kaiC基因全长序列。kaiC基因编码区长1554bo,基因GC碱基含量平均为41．76％,密码子第三位明显偏向于U。在基因上游385bp范围内发现一个可能的启动子序列和一些基因调控元件。KaiC蛋白分析发现了Walker A、DXXG、不完整的Walker B等重要模体和具有催化作用的功能位点。Southem杂交的结果证明kaiC基因在极大节旋藻中为单拷贝。极大节旋藻kaiC基因的特殊结构特征为研究kai基因簇的进化提供了重要的启示。     

测试条件对聚氯乙烯树脂稀溶液粘数的影响

聚氯乙烯树脂稀溶液粘数是聚氯乙烯树脂的一项重要指标,它的高低决定着产品的不同用途。本实验测试了几种不同测试条件如测试温度、黏度计毛细管直径、溶剂浓度等对聚氯乙烯树脂稀溶液粘数结果所产生的影响,通过实验数据的理论分析和计算,对原因进行了具体的分析。这些分析结果的获得对提高粘数分析的准确性,对于指导实际生产,规范检验操作,修订检验标准都有着重要的意义。     

混凝沉淀工艺对不同优势藻类的去除特性研究

为了考察混凝沉淀工艺的除藻性能在不同藻类优势期内的变化,将试验过程分为绿藻优势期和蓝藻优势期两个阶段,进行进水藻类群落结构特征及其变化对混凝沉淀除藻效能的影响研究.结果表明,混凝沉淀在绿藻优势期和蓝藻优势期的除藻效率分别为68.3%和40.4%,且各种藻类的去除效能并无明显的相互影响.蓝藻优势期的藻类去除率大大低于绿藻优势期,其根本原因在于占优势地位的微囊藻的生理生态特征.因此,把水中的所有藻类笼统地作为一个去除对象是不适宜的,应分析水中藻类群落结构特征,并根据特定原水中的优势藻种类进行针对性的除藻方案研究.     

基于自适应重采样的同步定位与地图构建

就移动机器人同步定位与地图构建展开研究,针对FastSLAM算法产生的粒子退化及粒子集重采样问题,提出了基于自适应重采样的FastSLAM算法。该算法首先计算粒子集的有效样本数,确定粒子退化程度。然后设定有效样本阈值,当有效样本数小于阈值时则进行重采样。仿真表明:与EKF-SLAM相比,基于自适应重采样FastSLAM重采样效率更高,鲁棒性更好,在机器人路径和陆标位置的估计上,也具有更高的精度。     

Discovery of Five New Ethylene-Forming Enzymes for Clean Production of Ethylene in E. coli

Ethylene is an essential platform chemical with a conjugated double bond, which can produce many secondary chemical products through copolymerisation. At present, ethylene production is mainly from petroleum fractionation and cracking, which are unsustainable in the long term, and harmful to our environment. Therefore, a hot research field is seeking a cleaner method for ethylene production. Based on the model ethylene-forming enzyme (Efe) {"type":"entrez-protein","attrs":{"text":"AAD16440.1","term_id":"4323597","term_text":"AAD16440.1"}}AAD16440.1 (6vp4.1.A) from Pseudomonas syringae pv. phaseolicol, we evaluated five putative Efe protein sequences using the data derived from phylogenetic analyses and the conservation of their catalytic structures. Then, pBAD expression frameworks were constructed, and relevant enzymes were expressed in E. coli BL21. Finally, enzymatic activity in vitro and in vivo was detected to demonstrate their catalytic activity. Our results show that the activity in vitro measured by the conversion of α-ketoglutarate was from 0.21–0.72 μmol ethylene/mg/min, which varied across the temperatures. In cells, the activity of the new Efes was 12.28–147.43 μmol/gDCW/h (DCW, dry cellular weight). Both results prove that all the five putative Efes could produce ethylene.     

Exploring the Effects of the Interaction of Carbon and MoS2 Catalyst on CO2 Hydrogenation to Methanol

Hydrogenation of CO₂ to form methanol utilizing green hydrogen is a promising route to realizing carbon neutrality. However, the development of catalyst with high activity and selectivity to methanol from the CO₂ hydrogenation is still a challenge due to the chemical inertness of CO₂ and its characteristics of multi-path conversion. Herein, a series of highly active carbon-confining molybdenum sulfide (MoS₂@C) catalysts were prepared by the in-situ pyrolysis method. In comparison with the bulk MoS₂ and MoS₂/C, the stronger interaction between MoS₂ and the carbon layer was clearly generated. Under the optimized reaction conditions, MoS₂@C showed better catalytic performance and long-term stability. The MoS₂@C catalyst could sustain around 32.4% conversion of CO₂ with 94.8% selectivity of MeOH for at least 150 h.     

High-Q microresonators on 4H-silicon-carbide-oninsulator platform for nonlinear photonics

The realization of high-quality (Q) resonators regardless of the underpinning material platforms has been a ceaseless pursuit, because the high-Q resonators pro...