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Advances in Bioscience and Biotechnology 2011年第6期2卷 397-403页

作者： Keshav Gopal Shivani Agarwal Aparna Dixit 不详

The ubiquitous Aeromonas hydrophila is responsible for several pathological conditions in fish and human. Like most gram negative bacteria, its virulence relies on outer membrane lipopolysachharide (LPS). The Leloir pathway enzyme UDP-galactose 4-epimerase (gale), plays an important role in the LPS biosynthesis, and therefore is a potential drug target. We have earlier carried out extensive biochemical and biophysical studies with histidine-tagged recombinant gale. However, for effective drug design it is desirable to understand the structure-function relation of a protein in its native form without any additional sequences or tags. In the present study, we report the high level expression, purification and characterization of recombinant gale (rgale) of Aeromonas hydrophila in its native form in E coli. The rgale expressed as a soluble protein was purified to near homogeneity. From 1 L of shake flask culture ~15 mg of purified rgale was obtained. The purified protein was biologically active with Km and Kcat values of 0.7 mM and 28.8 s–1, respectively. The enzyme exhibited a temperature and pH optima of 37。C and 7 - 9, respectively. Thus, the present study employed for soluble expression and purification of functionally active rgale without any tag bypasses the need for cumbersome strategies associated with removal of tag from purified protein.

关键词： Tag-Less gale Aeromonas hydrophila Recombinant Expression Kcat

Study on Cold Wave Weather in Hexi Corridor from March 12 to 14 in 2011

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Meteorological and Environmental Research 2012年第3期3卷 12-16页

作者： LUO Xiao-ling LIU Ming-chun YAN Zhi-min Drought Climate Changes and Disaster Mitigation Lab of CMA Key Lab of Drought Climate Changes and Disaster Mitigation in GansuLanzhou Drought Meteorological Institution of CMA Lanzhou 730020 China Wuwei Meteorological Bureau Wuwei 733000 China ThePropaganda Department of Wuwei City Wuwei 733000 China

[ Objectivel The aim was to study the cold wave in Hexi Corridor in 2011 and to summarize report experience. [ Method] Routine obser- vation data and Ecmwf numerical product were used to analyze the circulation background, causes and influential system of Hexi Corridor from March 12 to 14 in 2011. [Result] The cold wave in the mid-high latitude circulation in Northern hemisphere transited from radial type to warp type. High early basic temperature was the premise of cold wave. Drastic ground movement was the direct cause of cold wave. Prevailing cold advection was one primary cause of temperature reduction. Radiation in sunny days also posed certain influences on regional temperature. Factors weakened the gale were as follow, cold air largely in north area, cold air moving southeastward in diffusion, front passing early, upper and lower air conver- gence against the convection development and slow wind in high and lower air. [ Conclusion] The study provided important references for further enhancement of cold wave and gale report.

关键词： Cold wave Cold advection gale Causes Numerical report Experiences China

Analysis of Supercell Storm Structure and Mesocyclone Parameters

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Meteorological and Environmental Research 2010年第4期1卷 61-64页

作者：刁秀广王月兰朱君鉴山东省气象台山东济南250031 山东省滨州市气象局山东滨州256612

By using the high spatial and temporal resolution Jinan Doppler Weather Radar data and Jinan,Xingtai sounding data,the radar signature and mesocyclone parameters of 54 supercells during 2003-2008 were *** results showed that the probability of a supercell forming would be higher when SI (showalter index) ≤ -2℃,K (K index) ≥ 30℃ and 0-6 km wind shear>15 m/*** supercell storms can generally be divided into two categories,namely,type of isolation and mosaic *** the type of isolation,the max reflectivity,cell-based VIL,max reflectivity height,cell top,mesocyclone base and top were significantly higher than the mosaic ***-type supercells had significantly higher probability of hail,lower probability of gale than the mosaic *** mesocyclone attribute differences between isolation-type and mosaic type supercells determined the differences of storm structures and severe weather phenomenon.

关键词： Supercell structure Mesocyclone parameter Hail gale China

Analysis on Rare Squall Line Weather from Northeast

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Meteorological and Environmental Research 2010年第1期1卷 1-5页

作者：张昊任钟冬董平于凤英北京大学物理学院北京100871 山东省滨州市气象局山东滨州256600 山东省德州市气象局山东德州253009

Based on weather radar,automatic weather station and conventional observation data,the squall line from northeast occurred in the night of June 21,2005 in Binzhou City was *** analysis showed the characteristics of the meteorological elements and the system which played a major role was in the upper *** trough,shear line,high-altitude cold air,low-altitude warm air,and severe warming on the ground surface were conducive to the promotion of convective instability and resulted in the occurrence of squall *** squall line clouds on satellite images which showed dense and oval indicated that convection was strong and squall line may be *** the radar echo images the squall line showed herringbone or bow,bull's-eye structure and the main front was associated with thin ribbon weak echo which was the sign of the emergence of *** wind divergence observed on automatic weather station was related with downburst,and counter-clockwise changes of the wind direction in vertical wind profile products.

关键词： Squall line gale Severe convection China

New Characteristics of the Dust Weather in Northern Shaanxi in Recent 10 Years

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Meteorological and Environmental Research 2013年第4期4卷 29-32页

作者： Qiang Li Xiaolan Wei Min Liu Feng Su Aihua Li Yulin Meteorological Bureau in Shaanxi Yuyang Meteorological Bureau in Shaanxi Dingbian Meteorological Bureau in Shaanxi Wuqi Meteorological Bureau in Shaanxi Xixiang Meteorological Bureau in Shaanxi

[Objective] The research aimed to study new characteristics of the dust weather in northern Shaanxi in recent 10 years and correlation between dust weather and meteorological factor. [ Method] Based on observation data of 3 national basic meteorological stations （Yuyang District, Dingbian and Yan＇an） during 2001 -2010, the newest fact characteristics of temporal-spatial evolution for sand storm, sand blowing and floating dust in northern Shaanxi during 2001 -2010 were illustrated. Correlation between dust weather and meteorological factor （gale, precipitation and temperature） was analyzed. [Result] Compared with the 1990s, dust days in northern Shaanxi during 2001 -2010 still continued to decrease. There was no sand storm in Yan＇an. Sand storm days in northem region of north Shaanxi in most years was 1.0 -2.0 d. Sand blowing was main characteristics of the dust weather in northern Shaanxi, and proportion of the sand blowing days to dust days was 80% -90%. Dust days in Dingbi- an had good correlation with gale days, but gale days was smaller than dust days. That is to say, smaller wind force could induce dust weather. Decrease of the dust days presented inverse correlations with precipitaion and temperature. Precipitation increase and temperature rise could inhibit occurrence of the dust weather. Although total dust days decreased, sand storm in Yuyang District had increase tendency. [ Conclusion] The research had scientific, objective and practical significance for prediction of the climate change tendency in northern Shaanxi.

关键词： Dust weather New characteristics gale Precipitation Temperature Correlation China

肠炎沙门菌抑制炎症小体活化基因的筛选及功能研究

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肠炎沙门菌抑制炎症小体活化基因的筛选及功能研究

作者：黄婷婷扬州大学

学位级别：硕士

宿主天然免疫系统可以识别病原菌并诱导炎症应答,从而清除病原菌,这是宿主抵御微生物入侵的重要防线。炎症小体是国内外热门的研究领域,其中研究得最广泛的是 NLRC4（NLR family CARD domain-containing protein4）炎症小体和 NLRP3（NL... 详细信息

宿主天然免疫系统可以识别病原菌并诱导炎症应答,从而清除病原菌,这是宿主抵御微生物入侵的重要防线。炎症小体是国内外热门的研究领域,其中研究得最广泛的是 NLRC4（NLR family CARD domain-containing protein4）炎症小体和 NLRP3（NLR family pyrin domain-containing 3）炎症小体,它们在抵御病原微生物感染的过程中发挥重要作用。炎症小体是由模式识别受体（PRRs）,ASC接头蛋白和pro-Caspase-1组装形成的多蛋白复合物,pro-Caspase-1会发生自裂解成为活化形式,活化的Caspase-1能够促进细胞因子IL-1β和IL-18的成熟和分泌,并诱导细胞焦亡（Pyroptosis）。沙门菌（Salmonella）是一种重要的人兽共患病原菌,在感染宿主的过程中,细菌可以利用复杂的策略逃避免疫系统的清除,得以在宿主细胞内存活和复制,进而形成持续性感染。然而,沙门菌如何抑制炎症小体的活化逃避宿主免疫系统的清除在很大程度上仍然是未知的。基于此,本研究以肠炎沙门菌C50336ΔfliC（以下简称ΔfliC）为研究对象,构建转座子突变体文库,筛选参与调控炎症小体活化的基因,并探究其调控炎症小体活化的机制,为肠炎沙门菌新型防控技术和措施的建立提供新的思路。1肠炎沙门菌抑制炎症小体活化基因的筛选本研究以ΔfliC为亲本株,构建了肠炎沙门菌转座子随机插入失活突变体文库。以J774A.1细胞为感染模型,通过计算Z值高通量筛选诱导乳酸脱氢酶（LDH）释放水平具有显著性差异的突变株。共筛选了 1843株,诱导LDH释放水平显著性上调的有25株（Z ≥ 2）,显著性下调的有47株（Z ≤-2）。第二轮筛选对这些突变株在巨噬细胞中诱导炎症小体激活的能力进行了检测,结果显示,831号和1552号突变株在J774A.1细胞上稳定诱导更强的LDH释放、IL-1β分泌和Caspase-1活化水平。利用两轮半PCR对转座子插入序列进行定位,结果显示,这两株突变株的转座子分别插入在dinJ和gale的ORF中。dinJ编码沙门菌Ⅱ型毒素-抗毒素系统（TA）RelB/DinJ家族抗毒素,gale编码一种UDP-葡萄糖-4-差向异构酶。这些结果表明,肠炎沙门菌可能通过DinJ和gale抑制炎症小体的活化。分别构建了dinJ和gale的基因缺失突变株和回补株,并对这些菌株的生长特性和在J774A.1细胞上的黏附侵袭率进行了测定。结果显示,各缺失株和回补株之间的生长速率和J774A.1细胞上的黏附侵袭率均无显著差异。说明dinJ或gale的缺失不影响肠炎沙门菌的生长速率,也不影响其在J774A.1细胞上的黏附和侵袭能力。这些结果也表明肠炎沙门菌DinJ蛋白和gale蛋白抑制炎症小体的活化与黏附侵袭无关。2肠炎沙门菌DinJ蛋白抑制NLRP3炎症小体活化为了探究dinJ基因在调控炎症小体活化中发挥的作用,本研究用dinJ突变株和回补株感染J774A.1细胞,测定炎症小体活化的各项指标。结果显示,与ΔfliC亲本株相比,ΔfliCΔdinJ和ΔfliCΔdinJ::Vector感染的J774A.1细胞中检测到更强的LDH释放和IL-1β分泌,并且Caspase-1的活化也显著增强,ΔfliCΔdinJ::dinJ回补株感染组恢复到与ΔfliC亲本株相似的水平。野生型小鼠原代骨髓来源巨噬细胞（WT BMDMs）感染模型中也得到了相同的结果,ΔfliCΔdinJ缺失株诱导WT BMDMs的LDH释放、IL-1β分泌和Caspase-1活化水平显著高于ΔfliC亲本株感染组。这些结果表明肠炎沙门菌DinJ能够抑制炎症小体活化。此外,炎症小体各组分NLRP3、NLRC4和ASC蛋白的表达在各感染组之间无显著差异,表明DinJ抑制炎症小体的活化不是由抑制炎症小体组分的表达介导的。随后分别制备Casp1-/-、Nlrc4-/-和Nlrp3-/-BMDMs进一步探究DinJ蛋白抑制炎症小体的类型。在各菌株感染的Casp1-/-BMDMs中,检测不到IL-1β的分泌,LDH释放水平也降低,说明IL-1β的分泌依赖于Caspase-1。在Nlrc4-/-BMDMs感染组中,ΔfliC和ΔfliCΔdinJ::dinJ诱导的LDH释放、IL-1β分泌和Caspase-1活化均显著性低于ΔfliCΔdinJ,而在Nlrp3-/-BMDMs感染组中,dinJ缺失株和回补株诱导炎症小体活化的能力与亲本株相比均无明显差异。表明DinJ能够特异性抑制NLRP3依赖型炎症小体的激活,从而阻断炎性细胞因子的释放。本研究构建了 ΔfliC-pCX340和ΔfliC-pCX340-dinJ菌株,利用荧光共振能量转移（FRET）实验检

关键词：肠炎沙门菌 LDH 炎症小体 NLRP3 DinJ gale

Climatic Characteristics of Disastrous Weather in the Hunshandake Sandy Land

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Meteorological and Environmental Research 2021年第5期12卷 6-11页

作者： Guiying SONG Chun YING Jing JIANG Lu ZHANG Inner Mongolia Meteorological Observatory Hohhot 010051China Xilin Gol League Meteorological Bureau of Inner Mongolia Xilinhot 026099China

In order to explore the characteristics of climate change in the Hunshandake Sandy Land,the number of gale days,sandstorms,and extreme precipitation events in the sandy land from 1956 to 2018 were *** results show that in the Hunshandake Sandy Land,the number of gale days was the largest in spring;it first increased and then decreased from 1956 to *** number of gale days was large from 1955 to 1980,and decreased in fluctuation after *** mainly occurred in spring;the number of sandstorm days first increased and then *** was the largest during 1966-1970,and then decreased slowly;it was the smallest during *** the anomaly of about-0.16 d;it rose after the 21 *** threshold of extreme precipitation in the sandy land was high in the south and low in the *** threshold exceeded 80 mm in the southern part of the sandy land,and was less than 50 mm in sandy hinterland and its northern *** total frequency of extreme precipitation in the sandy land showed an increasing trend year by *** after 1982,the frequency of extreme precipitation rose *** precipitation events mostly happened in July and *** frequency of extreme precipitation events was the highest in Abaga Banner and the lowest in Duolun *** maximum daily precipitation appeared in Duolun County,reaching 142.3 mm.

关键词： Hunshandake Sandy Land gale Sandstorm Extreme precipitation Interdecadal variation