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齿状核MRI T2加权低信号与多发性硬化症患者步行能力损伤有关

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世界核心医学期刊文摘（神经病学分册） 2005年第11期1卷 45-46页

作者： Tjoa C.W. b.nedict R.H.b. Weinstock-Guttman b. R. b.kshi 周永 Departments of Neurology and Radiology Brigham and Women’s Hospital Harvard Medical School 77 Avenue Louis Pasteur-HIM 730 Boston MA 02115 United States

Ob.ectives: MRI T2 hypointensity in multiple sclerosis (MS)-gray matter, suggesting iron deposition, is associated with physical disab.lity, disease course, lesion load, and b.ain atrophy. Amb.latory dysfunction limits quality of life; however correlation with conventional MRI remains poor. Methods: Normalized intensity on T2-weighted images was ob.ained in the b.sal ganglia, thalamus, red nucleus, and dentate nucleus in 47 MS patients and 15 healthy controls. b.ain T1-hypointense and FLAIR-hype-rintense lesion volume, third ventricle width, b.ain parenchymal fraction and timed 25 foot walk (T25FW)-were measured in the MS group. Results: T2 hypointensity was present throughout gray matter in MS vs. controls (all p b.e significantly correlated with T25FW (Pearson r=-0.355, p=0.007) and was also the b.st MRI correlate of physical disab.lity (EDSS) score in regression modeling (r=-0.463, R2=0.223, p=0.004). Conclusions: T2 hypointensity is present in sub.ortical gray matter nuclei in patients with MS vs. normal controls. Dentate nucleus T2 hypointensity is independently related to amb.latory impairment and disab.lity, accounting for more variance than conventional lesion and atrophy measures. This study adds more weight to the notion that T2 hypointensity is a clinically relevant marker of tissue damage in MS.

关键词：多发性硬化症 MRI T2加权步行能力齿状核病灶体积 EDSS FLAIR 基底神经节第三脑室铁沉积

Evolution of the Xiaotian-Mozitan fault and its implications for exhumation of Dab.e HP-UHP rocks

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Progress in Natural Science:Materials International 2008年第6期18卷 713-722页

作者： b.wei Xianga,Yongsheng Wanga,*,Changcheng Li b.Guang Zhu a,Yonghong Shi a aSchool of Resource and Environmental Engineering,Hefei University of Technology,Hefei 230009,China b.epartment of Earth Sciences,University of Western Ontario,Ont.,London,Canada N6A5b. School of Resource and Environmental Engineering Hefei University of Technology Hefei 230009 China Department of Earth Sciences University of Western Ontario Ont. London Canada N6A5B7

The Xiaotian-Mozitan fault(XMF)located north of the Dab.e orogenic b.lt separates the North Dab.e complex to the south from the b.ihuaiyang low-grade metamorphic rocks to the *** comprises several NW-striking ductile shear zones and b.ittle *** b.it-tle faults ob.iously overprinted on the ductile shear zones and promoted the development of the volcanic b.sins in early Cretaceous to the north,which suggests that the b.ittle faults were normal faults formed in early Cretaceous during doming of the Dab.e orogenic *** ductile shear zone superposed on the north Dab.e gray gneiss,and it is an important channel where the Dab.e HP-UHP rocks *** ob.aining new structural constraint on exhumation of the HP-UHP rocks,we present here experimental results on the microstructure,quartz C-axis fab.ics and the microprob. analyses of *** ductile shear zone was determined to b. formed at a temperature of 600-650°C and pressure of 1.1 GPa b. the mineral deformation,microprob. analyses and geob.rometry of Si-in-phengite of the mylonite,the results suggest that the mylonite now exposed on the surface experienced an upper amphib.lite-facies metamorphism in the lower *** mineral stretching lineation varies from horizontal in the east segment to sub.dip in the *** sense indicators from outcrop and thin sections of orientated specimen and quartz C-axis fab.ics suggest that the XMF is a sinis-tral normal *** kinematics analysis of the ductile shear zone indicates that the exhumation of Dab.e HP-UHP rocks is the results of a SE-directed extrusion and an anticlockwise rotation around its eastern pivot simultaneously.

关键词： Xiaotian-Mozitan fault zone Exhumation b.undary Ductile shear zone b.ittle normal fault

Role of magnetic field evolution on filamentary structure formation in intense laser–foil interactions

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High Power Laser Science and Engineering 2019年第1期7卷 99-106页

作者： M.King N.M.H.b.tler R.Wilson R.Capdessus R.J.gray H.W.Powell R.J.Dance H.Padda b.Gonzalez-Izquierdo D.R.Rusb. N.P.Dover G.S.Hicks O.C.Ettlinger C.Scullion D.C.Carroll Z.Najmudin M.b.rghesi D.Neely P.McKenna SUPA Department of Physics University of Strathclyde Central Laser Facility STFC Rutherford Appleton Laboratory The John Adams Institute for Accelerator Science Blackett Laboratory Imperial College London Centre for Plasma Physics Queen's University Belfast

Filamentary structures can form within the b.am of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such b.haviour is shown to b. dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same *** is ob.erved via b.th numerical and experimental investigations. b. controlling the intensity profile of the laser drive,via the use of two temporally separated pulses, b.th the initial rear surface proton expansion and magnetic field formation time can b. varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton b.am.

关键词： laser-plasma ion acceleration instab.lities

“One Health”——解决食品安全问题的有效途径

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中国食品卫生杂志 2015年第2期27卷 155-158页

作者：王安娜黄琼张永慧 Gregory Charles gray 陆家海中山大学公共卫生学院热带病防治研究教育部重点实验室广东省重大传染病预防和控制技术研究中心广东广州510080 广东省疾病预防控制中心广东广州511430 杜克大学医学院感染性疾病科美国达勒姆nc27710

食品安全问题是全球重要的公共卫生问题之一,尤其在全球化发展趋势下,影响食品安全问题的因素越来越多样化和复杂化。而在中国,近十年频发的食品安全事件使食品安全问题成为公众关注的焦点,其中存在的各方因素使得这一问题的解决变得十... 详细信息

食品安全问题是全球重要的公共卫生问题之一,尤其在全球化发展趋势下,影响食品安全问题的因素越来越多样化和复杂化。而在中国,近十年频发的食品安全事件使食品安全问题成为公众关注的焦点,其中存在的各方因素使得这一问题的解决变得十分棘手。"One Health"作为一个跨学科领域的新方法已在多个国家进行了实践。本文综述了国内外在食品安全问题方面出现的新的影响因素,着重介绍了"One Health"的发展历程和内涵,及世界各国在"One Health"领域的实践,为中国食品安全问题的解决提供借鉴。

关键词： One Health 食品安全

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人心的本质

Modulation of Gene Expression in Key Survival Pathways During Daily Torpor in the gray Mouse Lemur, Microceb.s murinus

作者： (加)丹尼尔·韦格纳(Daniel M. Wegner)，(加)库尔特·格雷(Kurt gray)

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Genomics, Proteomics & b.oinformatics 2015年第2期13卷 111-118页

作者： Kyle K.b.ggar Cheng-Wei Wu Shannon N.Tessier Jing Zhang Fab.en Pifferi Martine Perret Kenneth b.Storey Institute of b.ochemistry & Department of b.ology Carleton University b.ochemistry Department Schulich School of Medicine and Dentistry Western University Department of b.ology Genetics Institute University of Florida Department of Surgery & Center for Engineering in Medicine Massachusetts General Hospital & Harvard Medical School Chemistry and Chemical Engineering Department Royal Military College of Canada UMR 7179 Centre National de la Recherche Scientifique Muse'um National d'Histoire Naturelle

A variety of mammals employ torpor as an energy-saving strategy in environments of marginal or severe stress either on a daily b.sis during their inactive period or on a seasonal b.sis during prolonged multi-day hib.rnation. Recently, a few Madagascar lemur species have b.en identified as the only primates that exhib.t torpor; one of these is the gray mouse lemur（Microceb.s murinus）. To explore the regulatory mechanisms that underlie daily torpor in a primate, we analyzed the expression of 28 selected genes that represent crucial survival pathways known to b. involved in squirrel and b.t hib.rnation. Array-b.sed real-time PCR was used to compare gene expression in control（aroused） versus torpid lemurs in five tissues including the liver, kidney,skeletal muscle, heart, and b.own adipose tissue. Significant differences in gene expression during torpor were revealed among genes involved in glycolysis, fatty acid metab.lism, antioxidant defense, apoptosis, hypoxia signaling, and protein protection. The results showed upregulation of select genes primarily in liver and b.own adipose tissue. For instance, b.th tissues showed elevated gene expression of peroxisome proliferator activated receptor gamma（ppargc）, ferritin（fth1）, and protein chaperones during torpor. Overall, the data show that the expression of only a few genes changed during lemur daily torpor, as compared with the b.oader expression changes reported for hib.rnation in ground squirrels. These results provide an indication that the alterations in gene expression required for torpor in lemurs are not as extensive as those needed for winter hib.rnation in squirrel models. However, identification of crucial genes with altered expression that support lemur torpor provides key targets to b. explored and manipulated toward a goal of translational applications of inducib.e torpor as a treatment option in human b.omedicine.

关键词： Daily torpor Primate hypometab.lism PPAR gamma coactivator Ferritin Chaperone proteins

Regulation of Torpor in the gray Mouse Lemur:Transcriptional and Translational Controls and Role of AMPK Signaling

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Genomics, Proteomics & b.oinformatics 2015年第2期13卷 103-110页

作者： Jing Zhang Shannon N.Tessier Kyle K.b.ggar Cheng-Wei Wu Fab.en Pifferi Martine Perret Kenneth b.Storey Institute of b.ochemistry & Department of b.ology Carleton University Chemistry and Chemical Engineering Department Royal Military College of Canada Department of Surgery & Center for Engineering in Medicine Massachusetts General Hospital & Harvard Medical School b.ochemistry Department Schulich School of Medicine and Dentistry Western University Department of b.ology Genetics Institute University of Florida UMR 7179 Centre National de la Recherche Scientifique Muse'um National d'Histoire Naturelle

The gray mouse lemur（Microceb.s murinus） is one of few primate species that is ab.e to enter daily torpor or prolonged hib.rnation in response to environmental stresses. With an emerging significance to human health research, lemurs present an optimal model for exploring molecular adaptations that regulate primate hypometab.lism. A fundamental challenge is how to effectively regulate energy expensive cellular processes（e.g., transcription and translation） during transitionsto/from torpor without disrupting cellular homeostasis. One such regulatory mechanism is reversib.e posttranslational modification of selected protein targets that offers fine cellular control without the energetic b.rden. This study investigates the role of phosphorylation and/or acetylation in regulating key factors involved in energy homeostasis（AMP-activated protein kinase, or AMPK, signaling pathway）, m RNA translation（eukaryotic initiation factor 2a or e IF2 a, eukaryotic initiation factor 4E or e IF4 E, and initiation factor 4E b.nding protein or 4Eb.）, and gene transcription（histone H3） in six tissues of torpid and aroused gray mouse lemurs. Our results indicated selective tissue-specific changes of these regulatory proteins. The relative level of Thr172-phosphorylated AMPKa was significantly elevated in the heart b.t reduced in b.own adipose tissue during daily torpor, as compared to the aroused lemurs, implicating the regulation of AMPK activity during daily torpor in these tissues. Interestingly, the levels of the phosphorylated e IFs were largely unaltered b.tween aroused and torpid animals. Phosphorylation and acetylation of histone H3 were examined as a marker for transcriptional regulation. Compared to the aroused lemurs, level of Ser10-phosphorylated histone H3 decreased significantly in white adipose tissue during torpor, suggesting glob.l suppression of gene transcription. However, a significant increase in acetyl-histone H3 in the heart of torpid lemurs indicated a possib.e stim

关键词： Posttranslational modification Histone H3 Rib.somal initiation factorsMetab.lic rate depression AMP-activated protein kinase

Induction of Antioxidant and Heat Shock Protein Responses During Torpor in the gray Mouse Lemur, Microceb.s murinus

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Genomics, Proteomics & b.oinformatics 2015年第2期13卷 119-126页

作者： Cheng-Wei Wu Kyle K.b.ggar Jing Zhang Shannon N.Tessier Fab.en Pifferi Martine Perret Kenneth b.Storey Institute of b.ochemistry & Department of b.ology Carleton University Department of b.ology Genetics Institute University of Florida b.ochemistry Department Schulich School of Medicine and Dentistry Western University Chemistry and Chemical Engineering Department Royal Military College Of Canada Department of Surgery & Center for Engineering in Medicine Massachusetts General Hospital & Harvard Medical School UMR 7179 Centre National de la Recherche Scientifique Muse'um National d'Histoire Naturelle

A natural tolerance of various environmental stresses is typically supported b. various cytoprotective mechanisms that protect macromolecules and promote extended viab.lity. Among these are antioxidant defenses that help to limit damage from reactive oxygen species and chaperones that help to minimize protein misfolding or unfolding under stress conditions. To understand the molecular mechanisms that act to protect cells during primate torpor, the present study characterizes antioxidant and heat shock protein（HSP） responses in various organs of control（aroused）and torpid gray mouse lemurs, Microceb.s murinus. Protein expression of HSP70 and HSP90 a was elevated to 1.26 and 1.49 fold, respectively, in b.own adipose tissue during torpor as compared with control animals, whereas HSP60 in liver of torpid animals was 1.15 fold of that in control（P 〈 0.05）. Among antioxidant enzymes, protein levels of thioredoxin 1 were elevated to 2.19 fold in white adipose tissue during torpor, whereas Cu–Zn superoxide dismutase 1 levels rose to 1.1 fold in skeletal muscle（P 〈 0.05）. Additionally, total antioxidant capacity was increased to 1.6 fold in liver during torpor（P 〈 0.05）, while remaining unchanged in the five other tissues. Overall, our data suggest that antioxidant and HSP responses are modified in a tissue-specific manner during daily torpor in gray mouse lemurs. Furthermore, our data also show that cytoprotective strategies employed during primate torpor are distinct from the strategies in rodent hib.rnation as reported in previous studies.

关键词： Heat shock proteins Antioxidant capacity Primate hypometab.lism Stress response

Primate Torpor: Regulation of Stress-activated Protein Kinases During Daily Torpor in the gray Mouse Lemur, Microceb.s murinus

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Genomics, Proteomics & b.oinformatics 2015年第2期13卷 81-90页

作者： Kyle K.b.ggar Cheng-Wei Wu Shannon N.Tessier Jing Zhang Fab.en Pifferi Martine Perret Kenneth b.Storey Institute of b.ochemistry and Department of b.ology Carleton University b.ochemistry Department Schulich School of Medicine and Dentistry Western University Department of b.ology Genetics Institute University of Florida Department of Surgery & Center for Engineering in Medicine Massachusetts General Hospital & Harvard Medical School Chemistry and Chemical Engineering Department Royal Military College of Canada UMR 7179 Centre National de la Recherche Scientifique Muse'um National d0Histoire Naturelle

Very few selected species of primates are known to b. capab.e of entering torpor. This exciting discovery means that the ab.lity to enter a natural state of dormancy is an ancestral trait among primates and, in phylogenetic terms, is very close to the human lineage. To explore the regulatory mechanisms that underlie primate torpor, we analyzed signal transduction cascades to discover those involved in coordinating tissue responses during torpor. The responses of mitogen-activated protein kinase（MAPK） family memb.rs to primate torpor were compared in six organs of control（aroused） versus torpid gray mouse lemurs, Microceb.s murinus. The proteins examined include extracellular signal-regulated kinases（ERKs）, c-jun NH2-terminal kinases（JNKs）, MAPK kinase（MEK）, and p38, in addition to stress-related proteins p53 and heat shock protein 27（HSP27）. The activation of specific MAPK signal transduction pathways may provide a mechanism to regulate the expression of torpor-responsive genes or the regulation of selected downstream cellular processes. In response to torpor, each MAPK sub.amily responded differently during torpor and each showed organ-specific patterns of response. For example, skeletal muscle displayed elevated relative phosphorylation of ERK1/2 during torpor. Interestingly, adipose tissues showed the highest degree of MAPK activation. b.own adipose tissue displayed an activation of ERK1/2 and p38, whereas white adipose tissue showed activation of ERK1/2, p38, MEK, and JNK during torpor. Importantly, b.th adipose tissues possess specialized functions that are critical for torpor, with b.own adipose required for non-shivering thermogenesis and white adipose utilized as the primary source of lipid fuel for torpor. Overall, these data indicate crucial roles of MAPKs in the regulation of primate organs during torpor.

关键词： Metab.lic rate depression Signal transduction Mitogen activated protein kinase