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Expression of matrix metalloproteinases and tissue inhibitor metalloproteinases increases in X-irradiated rat ileum despite the disappearance of CD8a T cells

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World Journal of Gastroenterology 2005年第40期11卷 6312-6321页

作者： Carine Strup-Perrot marie-Catherine Vozenin-Brotons marie Vandamme Christine Linard Denis Mathé Laboratoire d'étude des pathologies Radio-induites Laboratoire UPRES EA 27-10 'Radiosensibilité des tumeurs et tissus sains'

AIM： To investigate their expression and activity in the rat ileum after exposure to ionizing radiation along with that of the cellular effectors and molecular mediators involved in the regulation of MMPs. METHODS： Rats were exposed to a single 10-Gy dose of X-rays delivered to the abdomen. A combination of methods, such as zymography, immunohistochemistry and real time reverse transcriptase-polymerase chain reaction, were used to localize and quantify MMPs and the molecules involved in MMP activating and inhibitory pathways （plasmin/ plasminogen, TIMPs）, CD^8＋, as well as inflammatory （interleukin （IL）-1β, IL-8, tumor necrosis factor-s, TNF-α） and fibrogenic mediators （transforming growth factor- β1-3） within ileal tissue at 1, 3, and 7 d after irradiation. RESULTS： A marked increase in MMP-2 and -14 mRNA and protein levels associated with an increased activity of MMP-2 was observed in irradiated ileal tissue. MMP-2 and -14 expression was mainly observed in inflammatory, epithelial, and mesenchymal cells, whereas a slight increase in MMP-3 expression was detected in the few infiltrating macrophages at d i after irradiation. Conversely, MMP-1, -7, and -9 mRNA levels were not found to be affected by abdominal irradiation. Irradiation was found to induce disappearance of CD^8＋ cells. Furthermore, we have observed that TNF-α and IL-1β protein levels increased 6 h after irradiation, whereas those of IL-8 only increased after 3 d and was concomitant with neutrophil infiltration. In addition, the expressions of molecules involved in MMP activating and inhibitory pathways （urokinase-type plasminogen activator andtissue-type plasminogen activator; TIMP-1, TIMP-2, and plasminogen activator-inhibitor-i） were found to be increased after abdominal irradiation. CONCLUSION： This study showed that abdominal irradiation induces an acute remodeling of the ileum associated with an increased expression of MMPs and TIMPs that do not involve CD^8＋ T cells but involve mesenchymal and epi

关键词： Matrix metalloproteinases Irradiation Ileum T cells Cytokines

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Chemical Investigation of the NO_x Detection Mechanisms by Semiconductor Metal Oxide Nanoparticles

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稀有金属材料与工程 2006年第A3期35卷 40-42页

作者： marie-Isabelle Baraton Lhadi Merhari SPCTS-UMR CNRS 6638 Faculty of SciencesF-87060 LimogesFrance CERAMEC R&D F-87000 LimogesFrance

This work reports an FTIR study of the NO_x adsorption/desorption cycles on tin oxide nanosized particles under the operating conditions of real sensors (150℃,in presence of O_2).The chemical reactions are monitored in situ and correlated with the variations of the SnO_2 electrical *** the basis of the FTIR spectra,two contributing mechanisms for the NO_x detection are *** first one presents the formation of bridged nitrate groups bound to the SnO_2 surface via oxygen vacancies acting as electron donor *** second mechanism also involves surface oxygen vacancies in the coordination of NO_x,but this time the formation of NO_x anionic species is *** mechanisms lead to the decrease of the electrical conductivity under NO_x ***,the bridged nitrate groups are not reversible under gas desorption and thus irreversibly contaminate the surface after the first NO_x *** the contrary,the nitrosyl anionic species are reversible and,from the second NO_x adsorption/desorption cycle,ensure the reproducibility of the sensor response.

关键词： NO_x detection surface reactions FTIR spectroscopy Tin oxide SnO2 nanoparticles chemical sensors

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Zygotic chromosomal structural aberrations after paternal drug treatment

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Asian Journal of Andrology 2015年第6期17卷 939-941页

作者： Anne marie Downey Bernard Robaire Departments of Pharmacology and Therapeuticsand of Obstetrics and Gynecology McGill UniversityMontreal Quebec Canada.

In recent years, the field of male-mediated reproductive toxicology has received growing attention. It is now well-established that many drugs, chemicals, and environmental factors can harm male germ cells by inducing DNA damage. Male germ cells have extensive repair mechanisms that allow detection and repair of damaged DNA during the early phases of spermatogenesis. However, during the later phase of spermiogenesis, when the haploid spermatids undergo chromatin condensation and become transcriptionally quiescent, their ability to repair damaged DNA is lost. It is also thought that the highly compacted chromatin of the sperm can protect DNA against damage. Therefore, it is expected that late spermatids will be most susceptible to DNA damaging agents. Unrepaired or misrepaired damage in the germ cells leads to the generation of spermatozoa with DNA damage that can be transmitted to the next generation. Fortunately, the maternal DNA repair machinery is capable of recognizing and repairing, at least to some degree, damaged paternal DNA after fertilization in the zygote. Therefore, the efficiency of the maternal repair machinery will greatly influence the risk of transmitting paternal DNA damage to offspring.

关键词： Zygotic chromosomal treatment

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Heme oxygenase-1 system and gastrointestinal tumors

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World Journal of Gastroenterology 2010年第21期16卷 2633-2637页

作者： marie CM Lin Hsiangfu Kung The Brain Tumor Center and Neurosurgery Division Prince of Wales HospitalThe Chinese University of Hong Kong Li Ka Shing Institute of Medical Sciences the Chinese University of Hong Kong

Heme oxygenase-1(HO-1) system catabolizes heme into three products:carbon monoxide,biliverdin/bilirubin and free *** is involved in many physiological and pathophysiological processes.A great deal of data has demonstrated the roles of HO-1 in the formation,growth and metastasis of *** interest in this system by investigators involved in gastrointestinal tumors is fairly recent,and few papers on HO-1 have touched upon this *** review focuses on the current understanding of the physiological significance of HO-1 induction and its possible roles in the gastrointestinal tumors studied to *** implications for possible therapeutic manipulation of HO-1 in gastrointestinal tumors are also discussed.

关键词： Heme oxygenase-1 Gastrointestinal tumors

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A public health mission in Canada in response to the coronavirus disease 2019(COVID-19)pandemic

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Global Health Journal 2022年第4期6卷 231-236页

作者： marie Lavoie Department of Economics the Glendon School of Public and International AffairsGlendon CampusYork UniversityTorontoOntario M4N 3M6Canada

Many governments in the world reacted to the coronavirus disease 2019 pandemic by swiftly offering stimulus packages to their *** public unpreparedness was dramatic,it was not unexpected:many alarms had been *** by the federal and various provincial governments of Canada in core sectors predis-posed the country to the current situation and weakened its capacity to respond *** paper reviews the cumulative effects of these strategic orientations:a deficient investment strategy in fundamental science;dis-connect between laboratory work and the country's capacity to produce vaccines and antiviral drugs;the priority of cost efficiency that led to overwhelming dependency on foreign production of medical supplies;and dramatic spending cuts in public *** will discuss a Mission strategy to exit the crisis that takes a long-term perspec-tive,in which public interest and public health,combined with a strong State leadership,stimulate innovation and collaboration between national and international actors.

关键词： Fundamental research Innovation Mission Public health Pandemic

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Disaster Risk Reduction Efforts in the Greater Horn of Africa

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International Journal of Disaster Risk Science 2015年第1期6卷 49-61页

作者： marie-Ange Baudoin Tsegay Wolde-Georgis Consortium for Capacity Building Institute of Arctic and Alpine Research (INSTAAR) University of Colorado

This article assesses the current state of disaster risk reduction(DRR) in the Greater Horn of Africa(GHA),and focuses on interventions and policies to mitigate hydrometeorological risks. The research analyzes, as main case study, the program 'Regional Climate Prediction and Risk Reduction in the Greater Horn of Africa'funded by the Office of U.S. Foreign Disaster Assistance(USAID OFDA) in the early 2000 that targeted risk *** research method combines a desk review of relevant documents and research papers with surveys and interviews directed to key proponents of DRR across the GHA. Results highlight current strengths and weaknesses in the way DRR is implemented in the GHA. Significant improvements in the climate-forecasting capabilities in the GHA since the 2000 s are acknowledged, but the practice of DRR remains technology driven and impacts on the ground are limited. The key findings highlight the significant communication gaps that exist between the producers of climate information and their end users, the communities at risk. The article urges the establishment of bridges that connect climate experts, policymakers, and representatives of the local communities, and for the implementation of a feedback loop from forecast users to their producers, in order to strengthen risk resilience across the GHA.

关键词： Climate change Disaster risk management Greater Horn of Africa Hydrometeorological hazards Lessons learned Sub-Saharan Africa

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Seed wasp invasions promoted by unregulated seed trade affect vegetal and animal biodiversity

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Integrative Zoology 2012年第3期7卷 228-246页

作者： marie-Anne AUGER-ROZENBERG Alain ROQUES French National Institute for Agricultural Research(INRA) Forest Ecology(UR633)OrleansFrance

Cone and seed insects are considered the most important predators of tree seeds during the pre-dispersal phase of *** them,exotic seed chalcids in the genus Megastigmus invaded Europe as a result of the rapidly-increasing and mostly unregulated seed trade for afforestation and ornamental *** their economic impact in seed orchards,until recently,little attention was paid to the ecological impact of these *** the present study,selected case studies of alien Megastigmus *** considered to assess their specific impact on the potential of natural regeneration of native woody plants and on the native entomofauna competing for seed *** re-analyzed data from former studies that did not focus on these ecological interactions and,here,present previously unpublished *** of Douglas-fir,true cedars,true firs and wild roses were sampled all over Europe,and the relative importance of the native and invasive chalcid species was assessed as well as their specific impact on seed *** most cases,the recent arrival of alien chalcids resulted in a significant decrease in the regeneration potential of the host *** the absence of competitors,alien chalcids occupied the entire seed niche in Douglas-fir,but their impact tended to decrease after the arrival of invasive seed *** firs,alien chalcids tended to displace the native chalcids,but not in wild roses and cedars,where their damage was *** biological traits that might explain invasive success of alien chalcids are ***,no general invasive patterns seem to exist.

关键词： ecological impact invasion Megastigmus seed trade

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Environmental photocatalysis:Perspectives for China

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Science China Chemistry 2010年第9期53卷 1831-1843页

作者： HERRMANN Jean marie Institut de Recherches sur la Catalyse et l'Environnement de Lyon UMR 5256 CNRS/Université Lyon1 2 Av.Albert Einstein 69626 Villeurbanne Cedex

Photocatalysis is based on the double aptitude of the photocatalyst(essentially titania) to simultaneously adsorb reactants and absorb efficient *** photocatalysis is able to be efficient in Fine,"Green" and Environmental *** induces mild oxidations in the absence of water by generating active neutral atomic O* *** instance,the oxidation of 4-tert-butyl-toluene is 100% selective in *** water treatment,many toxic inorganic ions are oxidized in their harmless upper oxidized *** elimination of organic pollutants is the main field of water photocatalytic *** of aliphatic and aromatic pollutants are totally mineralized into CO2 and innocuous inorganic *** complex molecules,such as pesticides(herbicides,insecticides,fungicides,etc.) or dyes,are totally *** example of green chemistry is the total degradation of dyes in water,in particular for the azo-dyes,with 100% selective degradation of -N=N-azo-groups into *** is also active in the "bio-world" by killing bacteria(***,streptococcus,etc.) in water without *** pollutants can also be destroyed,especially all the VOC's(volatile organic compounds),providing certain air humidity enabling titania to produce cracking OH* *** chemical engineering reasons,the photocatalyst has to be fixed on a photo-inert *** these conditions,UV-irradiated titania-based photocatalysis could be applied to the elimination of air pollutants,VOC's,solvents,odors,chemicals,*** treatment has to be associated with water and solid waste treatment because of *** is conducted by covering water treatment ponds or lagunas by rafts on which large sheets of Ahlstrom paper are deposited,supporting titania associated with activated ***,virus AH5N2,a model virus close to H5N1,responsible for the avian flu could be totally *** is directly connected wi

关键词： photocatalysis green chemistry environmental chemistry air pollutants water pollutants solar energy China

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Heat Transfer in a Forced Wall Jet on a Heated Rough Surface

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Journal of Thermal Science 2000年第1期9卷 85-92页

作者： marie-Francoise Scibilia Lemfi - Centre National de la Recherche Scientifique Campus Universitaire

In this paper, an experimental investigation of a Iaminar wall jet in the presence of a heated wall with stationary particles on its surface, is reported. The wall jet was submitted to external acoustic vibrations amplifying the coherent structures appearing in the laminar region. A wind tunnel was used at very low Reynolds number. Mean velocity and turbulence intensity were measured by a constant temperature anemometer. Measurements were taken in the transition and turbulent regions. Embedded particles were outside the viscous sublayer and it was observed that their presence modifies significantly the flow characteristics in particular the boundary layer is thickened. This study can bring a better understanding of the structure of a flow when it is heated and forced on a rough wall.

关键词： heat transfer turbulence boundary layer wall jet roughness acoustics.

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Disaster Risk Resilience:Conceptual Evolution,Key Issues,and Opportunities

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International Journal of Disaster Risk Science 2022年第3期13卷 330-341页

作者： marie-Hélène Graveline Daniel Germain Institut des Sciences de l’Environnement(ISE) Universitédu QuébecàMontréalMontréalH3C 3P8Canada Department of Geography Universitédu QuébecàMontréalMontréalH3C 3P8Canada

Resilience has become a cornerstone for risk management and disaster ***,it has evolved extensively both etymologically and conceptually in time and across scientific *** concept has been(re)shaped by the evolution of research and practice *** the opposite of vulnerability for a long time,resilience was first defined as the ability to resist,bounce back,cope with,and recover quickly from the impacts of *** avoid the possible return to conditions of vulnerability and exposure to hazards,the notions of post-disaster development,transformation,and adaptation(build back better)and anticipation,innovation,and proactivity(bounce forward)were then ***,resilience is characterized by a multitude of components and several *** present a selection of 25 components used to define resilience,and an interesting linkage emerges between these components and the dimensions of risk management(prevention,preparedness,response,and recovery),offering a perspective to strengthen resilience through the development of *** its potential,resilience is subject to challenges regarding its operationalization,effectiveness,measurement,credibility,equity,and even its ***,it offers applicability and opportunities for local communities as well as an interdisciplinary look at global challenges.

关键词： Community Disaster risk Resilience Sustainable development

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