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Journal of Genetics and Genomics 2015年第6期42卷 287-299页

作者： Gerson Dierley Keppeke s.John Calise Edward K.L.Chan Luis eduardo C.Andrade Rheumatology Division Federal University of Sao Paulo Department of Oral Biology University of Florida Immunology Division Fleury Medicine and Health Laboratories

Inhibition of guanosine triphosphate（GTP） and cytidine triphosphate（CTP） biosynthetic pathways induces cells to assemble rod/ring（RR） structures,also named cytoophidia,which consist of the enzymes cytidine triphosphate synthase（CTPs） and inosine-50-monophosphate dehydrogenase 2（IMPDH2）.We aim to explore the interaction of CTPs and IMPDH2 in the generation of RR *** La and COs-7 cells were cultured in normal conditions or in the presence of 6-diazo-5-oxo-L-norleucine（DON）,ribavirin,or mycophenolic acid（MPA）.Over 90% of DON-treated cells presented RR *** He La cells,35% of the RR structures were positive for IMPDH2 alone,26% were CTPs alone,and 31% were IMPDH2/CTPs mixed,while in COs-7 cells,42% of RR were IMPDH2 alone,41% were CTPs alone,and 10% were IMPDH2/CTPs *** and MPA treatments induced only IMPDH2-based *** were also transfected with an N-terminal hemagglutinin（NHA）-tagged CTPs1 *** 95% of NHA-CTPs1 transfected cells with DON treatment presented IMPDH2-based RR and almost 100% presented CTPs1-based RR;when treated with ribavirin,over 94% of transfected cells presented IMPDH2-based RR and 37% presented CTPs1-based RR,whereas 2% of untreated transfected cells presented IMPDH2-based RR and 28% presented CTPs1-based *** results may help in understanding the relationship between CTP and GTP biosynthetic pathways,especially concerning the formation of filamentous RR structures.

关键词： Nucleotide synthesis Enzyme aggregation Enzyme inhibition IMPDH2 CTPs

Influence of Microstructures on Polarization Resistance and Hydrogen-Induced Cracking of a Micro-Alloyed steel submitted to Different Cooling Rates

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Journal of Iron and steel Research International 2011年第S1期18卷 168-172页

作者： González M R martins de Araújo D s Goldenstein H Alonso-Falleiros N Departamento de Engenharia Metalúrgica e de Materiais EscolaPolitécnicaUniversidade de Sao Paulo-SP-Brasil

The effect of different microstructures on the polarization resistance (Rp) and the hydrogen-induced cracking (HIC) of a micro-alloyed steel austenitized and submitted to different cooling rates was *** 19.1 x 6 x 2 mm,containing the whole thickness of the plate were extracted from a 20 mm plate and heat treated on a quenching dilatometer,were submitted to Rp and HIC corrosion *** Rp and HIC tests followed as close as possible AsTM G59 and NACE standard TM0284-2003,in this case,modified only with regard to the size of the *** samples transformed from austenite by a slow cooling (cooling rate of 0.5℃.s-1) showed higher susceptibility to hydrogen-induced cracking,with large cracks in the middle of the sample propagating along segregation bands,corresponding to the centerline of the plate *** cooling rates of 10℃.s-1,only small cracks were found in the matrix and micro cracks nucleated at non-metallic *** higher cooling rates (40℃.s-1) very few small cracks were detected,linked to non-metallic *** result suggests that structures formed by polygonal structures and segregation bands (were eutectoid microconstituents predominate) have higher susceptibility to *** predominantly formed by acicular ferrite make it difficult to propagate the cracks among non-oriented and interlaced acicular ferrite *** segregation bands containing eutectoid products also help inhibit cracking and crack propagation;segregation bands can function as pipelines for hydrogen diffusion and offer a path of stress concentration for the propagation of cracks,frequently associated to non-metallic *** resistance essays performed on the steel in theas received condition,prior to any heat treatment,showed larger differences between the regions of the plate,with a considerably lower Rp in the *** austenitization heat treatments followed by cooling rates of 0.5 e 10℃.s-1 made more uniform the

关键词： hydrogen induced cracking polarization resistance micro-alloyed steel control cooling

The influence of the blood pressure on the venous cerebral flow measured by magnetic susceptibility (sWI) technique

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Journal of Biomedical science and Engineering 2013年第3期6卷 426-434页

作者： Hugo martins Marlene Carreiras M. Margarida Ribeiro paulo sousa Carina silva-Forte Anatomy Department Medical Sciences Faculty of Lisbon Lisbon Portugal Department of Exact sciences Scientific Area of Mathematic from Polytechnic Institute Lisbon Portugal Department of sciences and Radiation Technologies Scientific Area of Radiology from Polytechnic Institute Lisbon Portugal Imaging Department Lusiadas Hospital Lisbon Portugal

susceptibility Weighted Image (sWI) is a Magnetic Resonance Imaging (MRI) technique that combines high spatial resolution and sensitivity to magnetic susceptibility differences between tissues, it is extremely sensitive to venous blood due to its iron content of deoxyhemoglobin. The aim of this study was to evaluate the differences in the cerebral venous vasculature produced by the value’s variation of blood pressure. 20 subjects (10 hypertensive and 10 normotensive patients) underwent a MRI system with field strength of 1.5 T using a synergy head coil (7 channels). The obtained sequences were T1w, T2w-FLAIR, T2* and sWI. The value of Contrast-to-Noise Ratio (CNR) was assessed in MinIP (Minimum Intensity Projection) and Magnitude images, through drawing free hand ROIs in venous structures: superior sagittal sinus (sss) Internal Cerebral Vein (ICV) and sinus Confluence (sC). The obtained values were presented in descriptive statistics-quartiles and extremes diagrams. The results were compared between groups. CNR shown higher values for normotensive group in MinIP (108.89 ± 6.907) to ICV;(238.73 ± 18.556) to sC and (239.384 ± 52.303) to sss. These values are bigger than images from Hypertensive group about 46 au in average. Comparing the results of Magnitude and MinIP images, there were obtained lower CNR values for the hypertensive group. There were differences in the CNR values between both groups, being these values more expressive in the large vessels-sss and sC. The sWI is a potential technique to evaluate and characterize the blood pressure variation in the studied vessels adding a physiological perspective to MRI and giving a new approach to the radiological vascular studies.

关键词： Blood Pressure susceptibility Normotensive Hypertensive Magnetic Resonance

Rainfall variability in the Brazilian northeast biomes and their interactions with meteorological systems and ENsO via CHELsA product

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Big Earth Data 2019年第4期3卷 315-337页

作者： Washington Luiz Félix Correia Filho JoséFrancisco De Oliveira-Júnior Dimas De Barros santiago paulo Miguel De Bodas Terassi paulo eduardo Teodoro Givanildo De Gois Claudio JoséCavalcante Blanco Pedro Henrique De Almeida souza Micejane da silva Costa Heliofábio Barros Gomes paulo JoséDos santos Institute of Atmospheric sciences(ICAT) Federal University of Alagoas(UFAL)MaceióBrazil Postgraduate Program in Biosystems Engineering(PGEB) Federal Fluminense University(UFF)NiteróiBrazil Postgraduate Program in Meteorology Unidade Acadêmica de Ciências Atmosféricas(UACA)Federal Universityof Campina Grande(UFCG)Campina GrandeBrazil Postgraduate Program in Physical Geography University of São Paulo(USP)São PauloBrazil Federal University of Mato Grosso do sul(UFMs) Chapadão do SulBrazil fschool of Industrial Metallurgical Engineering of Volta Redonda Technological CenterUniversidade Federal Fluminense(UFF)Volta RedondaBrazil Faculty of sanitary and Environmental Engineering(FAEsA/ITEC) Federal University of Pará(UFPA)BelémBrazil

Brazilian biomes are home to a significant portion of the world’s biodiversity,with a total of 14%of existing species and still concentrate 20%of the world’s water ***,changes in biomes have a direct impact on rainfall patterns and water *** on this,the objective was to evaluate the variability of rainfall in the four existing biomes in the Northeast Brazil(NEB)and their interaction with the ENsO climate variability mode and regional scale meteorological systems via CHELsA *** this,monthly rainfall data were used from 1979 to 2013,with a spatial resolution of 1 km×1 km of the CHELsA product,and seasonal and annual rainfall patterns were extracted via *** was found that the rainy season in the Amazon,Caatinga and Cerrado biomes occurred between January and April,with varying intensities,except for the Atlantic *** seasonality patterns are associated with the NEB meteorological systems,with emphasis on ITCZ(all Biomes),UTCV(Amazon,Caatinga and Cerrado),Frontal systems(extreme south of Caatinga,Cerrado and Atlantic Forest)and EWD/TWD in the(Atlantic Forest).In the inter-annual scale,the remarkable influence of ENsO was verified,mainly in the years 1983,1985,1989,1993,1998,2009 and *** is noteworthy that 1985 was the wettest year of the period,with a surplus in all biomes,while the driest year differs between the Amazon(1983),Atlantic Forest and Caatinga(1993)and Cerrado(2012)*** study via orbital product in NEB showed that anthropogenic processes and natural variability interfere with the forms of rain interception in the biomes and hence in rainfall patterns and water recycling in NEB.

关键词： Phytophysiognomy rainfall inter-annual variability water recycling climate change land use and occupation

P2X7 receptor blockade decreases inflammation,apoptosis,and enteric neuron loss during Clostridioides difficile toxin A-induced ileitis in mice

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World Journal of Gastroenterology 2022年第30期28卷 4075-4088页

作者： Ana A Q A santos Deiziane V s Costa Danielle A Foschetti Antoniella s G Duarte Conceicao s.martins Pedro M G soares Patricia Castelucci Gerly A C Brito Department of Morphology School of MedicineFederal University of CearaFortaleza 60430-170CearaBrazil Department of Physiology and Pharmacology School of MedicineFederal University of CearáFortaleza 60430-170CearaBrazil Department of Pathology and Legal Medicine School of MedicineFederal University of CearaFortaleza 60430-170CearaBrazil Department of Morphology(UFC) Federal University of CearaFortaleza 60430-170CearaBrazil Department of Anatomy Institute of Biomedical SciencesUniversity of São PauloSao Paulo 05508-270Brazil Department of Morphology Federal University of CearaFortaleza 60140-170CearaBrazil

Clostridioides difficile(***)is the most common pathogen causing health care-associated *** TcdA and TcdB have been shown to activate enteric neurons;however,what population of these cells is more profoundly influenced and the mechanism underlying these effects remain *** To characterize a specific population of TcdA-affected myenteric neurons and investigate the role of the P2X7 receptor in TcdA-induced ileal inflammation,cell death,and the changes in the enteric nervous system in *** swiss mice were used to model TcdA-induced ileitis in ileal loops exposed to TcdA(50μg/Loop)for 4 *** investigate the role of the P2X7 receptor,Brilliant Blue G(50 mg/kg,i.p.),which is a nonspecific P2X7 receptor antagonist,or A438079(0.7μg/mouse,i.p.),which is a competitive P2X7 receptor antagonist,were injected one hour prior to TcdA *** samples were collected to analyze the expression of the P2X7 receptor(by quantitative real-time polymerase chain reaction and immunohistochemistry),the population of myenteric enteric neurons(immunofluorescence),histological damage,intestinal inflammation,cell death(terminal deoxynucleotidyltransferasemediated dUTP-biotin nick end labeling),neuronal loss,and s100B synthesis(immunohistochemistry).REsULTs TcdA upregulated(Pssion of the P2X7 receptor gene in the ileal tissues,increasing the level of this receptor in myenteric neurons compared to that in control *** with the control mice indicated that TcdA promoted(Pss of myenteric calretinin+(Calr)and choline acetyltransferase+neurons and increased the number of nitrergic+and Calr+neurons expressing the P2X7 *** of the P2X7 receptor decreased TcdAinduced intestinal damage,cytokine release[interleukin(IL)-1β,IL-6,IL-8,and tumor necrosis factor-α],cell death,enteric neuron loss,and s100B synthesis in the mouse *** Our findings demonstrated that TcdA induced the upregulation of the P

关键词： Clostridioides difficile Clostridioides difficile toxin A P2X7 receptor Enteric nervous system Enteric neuron Enteric glia

Catalytic combustion of soot over ceria-zinc mixed oxides catalysts supported onto cordierite

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Journal of Environmental sciences 2014年第3期26卷 694-701页

作者： Leandro Fontanetti Nascimento Renata Figueredo martins Rodrigo Ferreira silva Osvaldo Antonio serra Department of Chemistry FFCLRP University of Sao Paulo

Modified substrates as outer heterogeneous catalysts was employed to reduce the soot generated from incomplete combustion of diesel or diesel/biodiesel blends, a process that harms the environment and public health. The unique storage properties of ceria （CeO2） makes it one of the most efficient catalysts available to date. Here, we proposed that ceria-based catalysts can lower the temperature at which soot combustion occurs; more specifically, from 610℃ to values included in the diesel exhausts operation range （300-450℃）. The sol-gel method was used to synthesize mixed oxide-based catalysts （CeO2：ZnO）; the resulting catalysts were deposited onto cordierite substrates. In addition, the morphological and structural properties of the material were evaluated by XRD, BET, TPR-H2, and sEM. Thermogravimetric （TG/DTA） analysis revealed that the presence of the catalyst decreased the soot combustion temperature by 200℃ on average, indicating that the oxygen species arise at low temperatures in this situation, promoting highly reactive oxidation reactions. Comparative analysis of soot emission by diffuse reflectance spectroscopy （DRs） showed that catalyst-impregnated cordierite samples efficiently oxidized soot in a diesel/biodiesel stationary motor： soot emission decreased by more than 70%.

关键词： soot oxidation mixed oxides ceria

Radiofrequency ablation for treatment of hypersplenism: A feasible therapeutic option

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World Journal of Gastroenterology 2015年第20期21卷 6391-6397页

作者： Guilherme Lopes P martins Joao paulo G Bernardes Marcello s Rovella Raphael G Andrade Publio Cesar C Viana paulo Herman Giovanni Guido Cerri Marcos Roberto Menezes Radiology and Image-Guided Intervention service Instituto do Cancer do Estado de Sao PauloUniversity of Sao Paulo Sao Paulo 01415-000 Brazil Department of Gastroenterology University of Sao Paulo Sao Paulo 01246-903 Brazil Instituto de Radiologia do Hospital das Clinicas da FMUsP Sao Paulo 05403-900 Brazil

We present a case of a patient with hypersplenism secondary to portal hypertension due to hepato-splenic schistosomiasis, which was accompanied by severe and refractory thrombocytopenia. We performed spleen ablation and measured the total spleen and ablated volumes with contrast-enhanced computed tomography and volumetry. No major complications occurred, thrombocytopenia was resolved, and platelet levels remained stable, which allowed for early treatment of the patient's underlying disease. Previous work has shown that splenic radiofrequency ablation is an attractive alternative treatment for hypersplenism induced by liver cirrhosis. We aimed to contribute to the currently sparse literature evaluating the role of radiofrequency ablation(RFA) in the management of hypersplenism. We conclude that splenic RFA appears to be a viable and promising option for the treatment of hypersplenism.

关键词： Portal hypertension Thrombocytopenia Hypersplenism Percutaneous radiofrequency ablation splenic ablation

Endoscopic therapy using a self-expandable metallic stent with an anti-migration system for postorthotopic liver transplantation anastomotic biliary stricture

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World Journal of Gastrointestinal Endoscopy 2022年第9期14卷 547-554页

作者： Larissa Wermelinger Pinheiro Fernanda Prata martins Gustavo Andrade De paulo Mðnica Lúcia Campos Contini Angelo paulo Ferrari Ermelindo Della Libera Department of Gastroenterology Federal University of São Paulo/Escola Paulista de MedicinaSão Paulo 04023-900Brazil Department of Endoscopy Unit Hosp Israelita Albert EinsteinSão Paulo 04042033Brazil

BACKGROUND Endoscopic therapy using multiple plastic stents(MPss)is the standard therapy for postorthotopic liver transplantation(p-OLT)anastomotic biliary stricture(ABs).However,this approach demands repeated *** studies us-ing fully covered self-expandable metallic stents(FCsEMs)have shown en-couraging results,but migration occurs in 10%to 40%of *** objective of this retrospective study was to evaluate the efficacy of endoscopic treatment using FCsEMs with an anti-migration system(Am-FCsEMs)in patients with p-OLT *** To evaluate the efficacy of endoscopic treatment using an Am-FCsEMs in patients with p-OLT *** This study was conducted in a private tertiary care centre in s?o paulo,Brazil and was approved by our institution's Human Research *** April 2018 to October 2020,regardless of previous endoscopic treatment(MPs or FCsEMs),17 patients with p-OLT ABs and indications for endoscopic therapy were included in this *** exclusion criteria were pregnancy,nonanastomotic biliary or hilar stricture,hepatic artery stenosis/thrombosis,isolated biliary fistulae,a distance shorter than 2 cm from the stricture to the hepatic hilum,and patient *** primary endpoint was the efficacy of p-OLT ABs endoscopic treatment using an Am-FCsEMs that re-mained in place for a 12-mo *** sphincterotomy was performed in patients with native papilla,and an Am-FCsEMs(10 mm in final diameter and 60 or 80 mm in length)was placed(Hanarostent TM MI Tech,Co).Balloon stricture dilation was performed only if necessary to introduce the *** Three patients were excluded due to loss to follow-up before stent *** the 14 patients included and followed,7 were women,and the average age was 56 years(range:28-76).The average period of Am-FCsEMs placement was 362±109 *** success occurred in all 14 patients(100%).There were no cases of distal stent *** resolution of the stricture occurred in 13/14 patien

关键词： Liver transplantation Endoscopy Endoscopic retrograde cholangiopancreatography Biliary strictures self-expandable metallic biliary stents

Dendritic Growth, Eutectic Features and Their Effects on Hardness of a Ternary sn–Zn–Cu solder Alloy

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Acta Metallurgica sinica(English Letters) 2017年第6期30卷 528-540页

作者： Bismarck Luiz silva Rodrigo Valenzuela Reyes Amauri Garcia Joséeduardo spinelli Department of Materials Engineering Federal University of Rio Grande do Norte-UFRNNatalRN 59078-970Brazil Department of Materials Engineering Federal University of Sao Carlos-UFSCarSao CarlosSP 13565-905Brazil Department of Manufacturing and Materials Engineering University of CampinasUNICAMPCampinasSP 13083-860Brazil

The present investigation is based on the results of a directionally solidified （Ds） sn-9 wt%Zn-2 wt%Cu alloy, including primary/secondary/tertiary dendrite arm spacings of the sn-rich matrix, the morphologies of the eutectic mixture and the corresponding interphase spacing, the nature and proportion of the Cu-Zn intermetallic compound （IMC）. The main purpose is to establish interrelations of these microstructure features with experimental solidification thermal parameters, such as cooling rates and growth rates （v）, macrosegregation and hardness. such interrelations are interesting for both industry and academy since they represent a tool permitting the preprogramming of final properties based on the design of the microstructure. In the case of sn-Zn-Cu alloys, hardly anything is known about the combined effects of the length scale of the microstructure and fraction and distribution of the primary IMC on hardness. The alloy microstructure is composed of a β-sn dendritic region, surrounded by a eutectic mixture of α-Zn and β-sn phases and the γ-Cu5Zn8 IMC. The eutectic interphase spacing varies in the range 1.2-3.6 μm, with the α-Zn phase having a globular morphology for ν 〉 0.5 mm/s and a needle-like morphology for ν 〈 0.3 mm/s. A modified Hall-Petch-type experimental expression relating hardness to the interphase spacing is proposed.

关键词： sn-Zn-Cu solder alloy solidification Microstructure Eutectic morphology Hardness

Transpiration and growth responses by Eucalyptus species to progressive soil drying

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Journal of Forestry Research 2022年第5期33卷 1529-1543页

作者： Marcel Carvalho Abreu Alvaro Augusto Vieira soares Cleverson Henrique de Freitas Fabrina Bolzan martins Department of Environment science Forest InstituteFederal Rural University of Rio de JaneiroSeropédicaRio de Janeiro 23890-000Brazil Institute of Agricultural sciences Federal University of UberlândiaMonte CarmeloMinas Gerais 38405-302Brazil “Luiz de Queiroz”College of Agriculture University of São PauloPiracicabaSão Paulo 13418-900Brazil Natural Resources Institute Federal University of ItajubáItajubáMinas Gerais 37500-903Brazil

The regulation of plant transpiration is a key factor affecting transpiration efficiency, growth and adaptation of Eucalyptus species to limited water availability in tropical and subtropical environments. However, few studies have related this trait to the performance of Eucalyptus seedlings and none have investigated the influence of vapor pressure deficit (VPD) on transpiration rates and growth. In this study, the transpiration and growth responses of seedlings of Eucalyptus urophylla (s.T. Blake) and Eucalyptus cloeziana (F. Muell.) to progressive soil water deficits were evaluated under semi-controlled conditions using the fraction of transpirable soil water (FTsW) method. In addition, the influence of VPD on seedling transpiration, development and growth was also investigated. The FTsW threshold ranged from 0.40 to 0.99 for the transpiration rate and from 0.32 to 0.97 for the development and growth variables. Little or no changes in the FTsW threshold were detected in response to changes in atmospheric VPD. Both Eucalyptus species presented a conservation strategy under drought stress. In addition, water-conserving mechanisms during the seedling phase were related to rapid stomatal closure, reduced leaf area, and number of leaves.

关键词： soil water deficit Fraction of transpirable soil water Transpiration seedling growth Vapor pressure deficit