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Molecular evolution of the rice miR395 gene family

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Cell Research 2005年第8期15卷 631-638页

作者： Sreelatha GUDDETI,Chuck H. LESEBERG,Mitrick A. JOHNS Department of Biological Sciences Northern Illinois University DeKalb IL 60115 USA Department of Biological Sciences Northern Illinois University DeKalb IL 60115 USA Department of Biological Sciences Northern Illinois University DeKalb IL 60115 USA

MicroRNAs (miRNAs) are 20-22 nucleotide non-coding RNAs that play important roles in plant and animal development. They are usually processed from larger precursors that can form stem-loop structures. Among 20 miRNA families that are conserved between Arabidopsis and rice, the rice miR395 gene family was unique because it was organized into compact clusters that could be transcribed as one single transcript. We show here that in fact this family had four clusters of total 24 genes. Three of these clusters were segmental duplications. They contained miR395 genes of both 120 bp and 66 bp long. However, only the latter was repeatedly duplicated. The fourth cluster contained miR395 genes of two different sizes that could be the consequences of intergenic recombination of genes from the first three clusters. On each cluster, both 1-duplication and 2-duplication histories were observed based on the sequence similarity between miR395 genes, some of which were nearly identical suggesting a recent origin. This was supported by a miR395 locus survey among several species of the genus Oryza, where two clusters were only found in species with an AA genome, the genome of the cultivated rice. A comparative study of the genomic organization of Medicago truncatula miR395 gene family showed significant expansion of intergenic spaces indicating that the originally clustered genes were drifting away from each other. The diverse genomic organizations of a conserved microRNA gene family in different plant genomes indicated that this important negative gene regulation system has undergone dramatic tune-ups in plant genomes.

关键词： gene duplication genome evolution Oryza sativa microRNA.

Vertical load capacities of roof truss cross members

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International Journal of Mining Science and Technology 2016年第3期26卷 517-520页

作者： Gearhart David F. Mohamed Khaled Morsy Office of Mine Safety & Health Research National Institute for Occupational Safety & Health

Trusses used for roof support in coal mines are constructed of two grouted bolts installed at opposing forty-five degree angles into the roof and a cross member that ties the angled bolts together. The load on the cross member is vertical, which is transverse to the longitudinal axis, and therefore the cross member is loaded in the weakest direction. Laboratory tests were conducted to determine the vertical load capacity and deflection of three different types of cross members. Single-point load tests, with the load applied in the center of the specimen and double-point load tests, with a span of 2.4 m, were conducted. For the single-point load configuration, the yield of the 25 mm solid bar cross member was nominally 98 kN of vertical load, achieved at 42 cm of deflection. For cable cross members, yield was not achieved even after 45 cm of deflection. Peak vertical loads were about 89 kN for 17 mm cables and67 kN for the 15 mm cables. For the double-point load configurations, the 25 mm solid bar cross members yielded at 150 kN of vertical load and 25 cm of deflection. At 25 cm of deflection individual cable strands started breaking at 133 and 111 kN of vertical load for the 17 and 15 mm cable cross members respectively.

关键词：竖向承载力横梁桁架屋顶垂直载荷负载能力竖向荷载点荷载试验

Plasma microRNA profiles distinguish lethal injury in acetaminophen toxicity: A research study

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World Journal of Gastroenterology 2012年第22期18卷 2798-2804页

作者： Jeanine Ward Shashi Bala Jan Petrasek Gyongyi Szabo Department of Emergency Medicine University of Massachusetts Medical School 55 Lake Avenue North Worcester MA 01655 United States Division of Gastroenterology Department of Medicine University of Massachusetts Medical School 364 Plantation Street Worcester MA 01655 United States

AIM: To investigate plasma microRNA (miRNA) profiles indicative of hepatotoxicity in the setting of lethal acetaminophen (APAP) toxicity in mice. METHODS: Using plasma from APAP poisoned mice, either lethally (500 mg/kg) or sublethally (150 mg/kg) dosed, we screened commercially available murine microRNA libraries (SABiosciences, Qiagen Sciences, MD) to evaluate for unique miRNA profiles between these two dosing parameters. RESULTS: We distinguished numerous, unique plasma miRNAs both up- and downregulated in lethally compared to sublethally dosed mice. Of note, many of the greatest up- and downregulated miRNAs, namely 574-5p, 466g, 466f-3p, 375, 29c, and 148a, have been shown to be associated with asthma in prior studies. Interestingly, a relationship between APAP and asthma has been previously well described in the literature, with an as yet unknown mechanism of pathology. There was a statistically significant increase in alanine aminotransferase levels in the lethal compared to sublethal APAP dosing groups at the 12 h time point (P 0.001). There was 90% mortality in the lethally compared to sublethally dosed mice at the 48 h time point (P = 0.011). CONCLUSION: We identified unique plasma miRNAs both up- and downregulated in APAP poisoning which are correlated to asthma development.

关键词： microRNA 对乙酰氨基酚血浆毒性亚致死剂量 miRNA 型材谷丙转氨酶

Elevated axonal membrane permeability and its correlation with motor deficits in an animal model of multiple sclerosis

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Translational Neurodegeneration 2017年第1期6卷 29-36页

作者： Gary Leung Melissa Tully Jonathan Tang Shengxi Wu Riyi Shi Department of Basic Medical Sciences College of Veterinary MedicinePurdue UniversityWest LafayetteIN 47907USA Weldon School of Biomedical Engineering Purdue UniversityWest LafayetteIN 47907USA MSTP program Indiana University School of MedicineIndianapolisINUSA Department of Neurobiology Fourth Military Medical UniversityXi’anChina

Background:It is increasingly clear that in addition to myelin disruption,axonal degeneration may also represent a key pathology in multiple sclerosis(MS).Hence,elucidating the mechanisms of axonal degeneration may not only enhance our understanding of the overall MS pathology,but also elucidate additional therapeutic *** objective of this study is assess the degree of axonal membrane disruption and its significance in motor deficits in EAE ***:Experimental Autoimmune Encephalomyelitis was induced in mice by subcutaneous injection of myelin oligodendrocyte glycoprotein/complete Freud’s adjuvant emulsion,followed by two intraperitoneal injections of pertussis *** assessment was performed using a 5-point *** Peroxidase Exclusion test was used to quantify the disruption of axonal *** glycol was prepared as a 30%(w/v)solution in phosphate buffered saline and injected ***:We have found evidence of axonal membrane disruption in EAE mice when symptoms peak and to a lesser degree,in the pre-symptomatic stage of EAE ***,polyethylene glycol(PEG),a known membrane fusogen,significantly reduces axonal membrane disruption in EAE *** PEG-mediated membrane repair was accompanied by significant amelioration of behavioral deficits,including a delay in the emergence of motor deficits,a delay of the emergence of peak symptom,and a reduction in the severity of peak ***:The current study is the first indication that axonal membrane disruption may be an important part of the pathology in EAE mice and may underlies behavioral *** study also presents the initial observation that PEG may be a therapeutic agent that can repair axolemma,arrest axonal degeneration and reduce motor deficits in EAE mice.

关键词： Multiple sclerosis EAE Axonal membrane damage Polyethylene glycol Acrolein Horseradish Peroxidase Membrane permeability Neurodegeneration

Epigenetic regulation in alcoholic liver disease

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World Journal of Gastroenterology 2011年第20期17卷 2456-2464页

作者： Pranoti Mandrekar Department of Medicine University of Massachusetts Medical School

Alcoholic liver disease(ALD)is characterized by steatosis or fat deposition in the liver and inflammation,which leads to cirrhosis and hepatocellular *** of target genes without involving changes in DNA sequence seems to contribute greatly to liver injury. Chromatin modifications including alterations in histones and DNA,as well as post-transcriptional changes collectively referred to as epigenetic effects are altered by *** studies have pointed to a significant role for epigenetic mechanisms at the nucleosomal level influencing gene expression and disease outcome in ALD. Specifically,epigenetic alterations by alcohol include histone modifications such as changes in acetylation and phosphorylation,hypomethylation of DNA,and alterations in *** modifications can be induced by alcoholinduced oxidative stress that results in altered recruitment of transcriptional machinery and abnormal gene *** these mechanisms in initiation and progression of ALD is becoming a major area of *** review summarizes key epigenetic mechanisms that are dysregulated by alcohol in the *** by alcohol in histone and DNA modifications,enzymes related to histone acetylation suchas histone acetyltransferases,histone deacetylases and sirtuins,and methylation enzymes such as DNA methyltransferases are *** modifications and miRNA alterations that result in immune cell dysfunction contributing to inflammatory cytokine production in ALD is ***,the role of alcohol-mediated oxidative stress in epigenetic regulation in ALD is described. A better understanding of these mechanisms is crucial for designing novel epigenetic based therapies to ameliorate ALD.

关键词：遗传调控酒精性表观组蛋白乙酰转移酶肝病组蛋白修饰 DNA序列基因表达水平

Role of the virion host shutoff protein in neurovirulence of monkey B virus(Macacine herpesvirus 1)

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Virologica Sinica 2014年第5期29卷 274-283页

作者： Darla Black Jerry Ritchey Mark Payton Richard Eberle Department of Veterinary Pathobiology Center for Veterinary Health Sciences Oklahoma State University Department of Statistics Oklahoma State University

Monkey B virus(Macacine herpesvirus 1; BV) is noted for its extreme neurovirulence in humans. Since the vhs protein encoded by the UL41 gene has been shown to be a neurovirulence factor in the related human herpes simplex viruses, the role of the UL41 gene in BV neurovirulence was investigated. BV mutants were constructed that lacked the entire UL41 ORF(Δ41) or had the RNase active site mutated(Δ41A). Neither mutant shut off host protein synthesis, degraded β-actin mRNA, or prevented an IFN-β response, indicating that the vhs protein and its RNase activity are both necessary for these activities. Replication of both mutants in primary mouse cells was impaired and they exhibited a prolonged disease course in mice. Whereas Δ41 infected mice were euthanized for symptoms related to central nervous system(CNS) infection, Δ41A infected mice were euthanized primarily for symptoms of autonomic nervous system dysfunction. While neuroinvasiveness was not affected, lesions in the CNS were more limited in size, anatomical distribution, and severity than for wild-type virus. These results indicate that the vhs protein affects the general replicative efficiency of BV in vivo rather than being a specific neurovirulence factor critical for invasion of or preferential replication in the CNS.

关键词： herpesvirus monkey B virus UL41 virion host shutoff neurovirulence

Tea beverage in chemoprevention and chemotherapy of prostate cancer

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Acta Pharmacologica Sinica 2007年第9期28卷 1392-1408页

作者： Imtiaz A SIDDIQUI Mohammad SALEEM Vaqar M ADHAMI Mohammad ASIM Hasan MUKHTAR Department of Dermatology University of WisconsinMedical Sciences CenterRoom B-25 1300 University AvenueMadisonWisconsin 53706USA

Prostate cancer (PCa) is the most frequently diagnosed malignancy and the sec-ond leading cause of cancer-related deaths in American males with similar trendsin many western *** existing treatment approaches and surgical inter-vention have not been able to effectively cope with this dreaded *** reasons,it is necessary to intensify our efforts for a better understanding ofthe disease process and for the development of novel approaches for its preven-tion and *** on considerable evidence from in vivo and in vitro dataand epidemiological studies,in recent years the beverage tea has gained consid-erable attention for reducing the risk of several *** of the cancerpreventive effects of tea,especially green tea appear to be mediated by the polyphe-nols present *** evidence suggests that the incidence andoccurrence of PCa is lower in populations that consume tea *** evi-dence suggests that tea polyphenols could be extrapolated to optimize theirchemopreventive properties against *** represents an excellent candidatedisease for chemoprevention because it is typically diagnosed in men over 50years of age and therefore,even a modest delay in neoplastic development achievedthrough pharmacological or nutritional intervention could result in a substantialreduction in the incidence of clinically detectable *** this review weaddress the issue of possible use of tea,especially green tea,for the prevention aswell as treatment of PCa.

关键词： Green tea (-)epigallocatechin-3-gallate (-) epicatechin apoptosis androgen receptor PSA tumor xenograft epidemiology clinical studies

Mice Deficient in NF-κB p50 and p52 or RANK Have Defective Growth Plate Formation and Post-natal Dwarfism

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Bone Research 2013年第4期1卷 336-345页

作者： Lianping Xing Di Chen Brendan F.Boyce Department of Pathology and Laboratory Medicine University of Rochester Medical Center Department of Biochemistry Rush University Medical Center

NF-κBp50/p52 double knockout （dKO） and RANK KO mice have no osteoclasts and develop severe osteopetrosis associated with dwarfism. In contrast, Op/Op mice, which form few osteoclasts, and Src KO mice, which have osteoclasts with defective resorptive function, are osteopetrotic, but they are not dwarfed. Here, we compared the morphologic features of long bones from p50/p52 dKO, RANK KO, Op/Op and Src KO mice to attempt to explain the differences in their long bone lengths. We found that growth plates in p50/p52 dKO and RANK KO mice are significantly thicker than those in WT mice due to a 2-3-fold increase in the hypertrophic chondrocyte zone associated with normal a proliferative chondrocyte zone. This growth plate abnormality disappears when animals become older, but their dwarfism persists. Op/Op or Src KO mice have relatively normal growth plate morphology. In-situ hybridization study of long bones from pS0/ p52 dKO mice showed marked thickening of the growth plate region containing type 10 collagen-expressing chondrocytes. Treatment of micro-mass chondrocyte cultures with RANKL did not affect expression levels of type 2 collagen and Sox9, markers for proliferative chondrocytes, but RANKL reduced the number of type 10 collagen-expressing hypertrophic chondrocytes. Thus, RANK/NF-κB signaling plays a regulatory role in post-natal endochondral ossification that maintains hypertrophic conversion and prevents dwarfism in normal mice.

关键词： NF-κB RANK growth plate chondrocytes dwarfism

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面向对象的BESⅢ探测器模拟系统

高能物理与核物理 2006年第5期30卷 371-377页

作者：邓子艳曹国富付成栋何苗刘怀民冒亚军夏宇尤郑昀袁野汤睿刘英杰马秋梅马想王大勇毛泽普文硕平王喆李卫东张长春邱进发张学尧张晓梅张瑶郑直俞国威黄性涛蒋林立臧石磊中国科学院高能物理研究所北京100049 北京大学北京100871 湖南大学长沙410082 山东大学济南250100 中国科技大学合肥230026

BESⅢ探测器的模拟软件包BOOST,是基于Geant4开发的面向对象的模拟软件．BOOST全面地模拟了BESⅢ探测器的物质和几何结构,给出了粒子在各个子探测器中的击中信息,以ASCⅡ码文件的形式输出原始数据和MC truth信息可供重建软件开发和物理... 详细信息

BESⅢ探测器的模拟软件包BOOST,是基于Geant4开发的面向对象的模拟软件．BOOST全面地模拟了BESⅢ探测器的物质和几何结构,给出了粒子在各个子探测器中的击中信息,以ASCⅡ码文件的形式输出原始数据和MC truth信息可供重建软件开发和物理分析使用,初步结果显示BOOST的模拟是合理的．

关键词： BESⅢ探测器模拟 Geant4