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HP0953-hypothetical virulence factor overexpresion and localization during Helicobacter pylori infection of gastric epithelium

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World Journal of Gastroenterology 2022年第29期28卷 3886-3902页

作者： Nancy K Arteaga-Resendiz Gerardo E Rodea Rosa María Ribas-Aparicio Alma l Olivares-Cervantes Juan Arturo Castelán-Vega Joséde Jesús Olivares-Trejo Sandra Mendoza-Elizalde Edgar O lópez-Villegas Christian Colín Pamela Aguilar-Rodea alfonso reyes-lópez Marcela Salazar García Norma Velázquez-Guadarrama laboratorio de Investigación en Enfermedades Infecciosas Hospital Infantil de México Federico GómezMexico City 06720Mexico Posgrado en Biomedicina y Biotecnología Molecular Laboratorio de Producción y Control de BiológicosEscuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico laboratorio de Adquisición de Hierro Universidad Autónoma de la Ciudad MéxicoPosgrado Ciencias GenómicaMexico City 03100Mexico laboratorio Central de Microscopía Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico Centro de estudios económicos y sociales en salud Hospital Infantil de México Federico GómezMexico City 06720Mexico laboratorio de Investigación en Biología del Desarrollo y Teratogénesis Experimental Hospital Infantil de México Federico GómezMexico City 06720Mexico

BACKGROUND The high prevalence and persistence of Helicobacter pylori(H. pylori) infection, as well as the diversity of pathologies related to it, suggest that the virulence factors used by this microorganism are varied. Moreover, as its proteome contains 340hypothetical proteins, it is important to investigate them to completely understand the mechanisms of its virulence and survival. We have previously reported that the hypothetical protein HP0953 is overexpressed during the first hours of adhesion to inert surfaces, under stress conditions, suggesting its role in the environmental survival of this bacterium and perhaps as a virulence *** To investigate the expression and localization of HP0953 during adhesion to an inert surface and against gastric(AGS) *** Expression analysis was performed for HP0953 during H. pylori adhesion. HP0953 expression at 0,3, 12, 24, and 48 h was evaluated and compared using the Kruskal-Wallis equality-of-populations rank test. Recombinant protein was produced and used to obtain polyclonal antibodies for immunolocalization. Immunogold technique was performed on bacterial sections during adherence to inert surfaces and AGS cells, which was analyzed by transmission electron microscopy. HP0953 protein sequence was analyzed to predict the presence of a signal peptide and transmembrane helices, both provided by the ExPASy platform, and using the GlYCOPP platform for glycosylation sites. Different programs, via, I-TASSER, RaptorX, and HHalign-Kbest, were used to perform three-dimensional *** HP0953 exhibited its maximum expression at 12 h of infection in gastric epithelium *** technique revealed HP0953 localization in the cytoplasm and accumulation in some peripheral areas of the bacterial body, with greater expression when it is close to AGS *** analysis revealed the presence of a signal peptide that interacts with the transmembrane region and then allows the release of the protein

关键词： Hypothetical protein HP0953 Adherence Helicobacter pylori Glycocalyx Virulence factor Persistence

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Effect of the initial ECAP passes on crystal texture and residual stresses of 5083 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 801-808页

作者： l.Romero-Reséndiz A.Flores-Rivera I.A.Figueroa C.Braham C.reyes-Ruiz I.alfonso G.González Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCd.de México 04510México Procédés et Ingénierie en Mécanique et Matériaux Arts et MétiersParis 75013France Departamento de Diseño y Manufactura Facultad de IngenieríaUniversidad Nacional Autónoma de MéxicoPIIT Apodaca 66629México Instituto de Investigaciones en Materiales Unidad MoreliaUniversidad Nacional Autónoma de MéxicoMorelia 58190México

To produce a highly refined microstructure,several metals or alloys have been processed via equal-channel angular pressing(ECAP).In this work,the mechanical and microstructural changes of the 5083 aluminum alloy in H11 condition after processed by two ECAP passes were *** ECAP H13 steel die with an inner angle(α)of 120°and outer curvature(β)of 20°was *** microstructural changes were associated with the loss of texture *** morphologies of the Mg2Si andα-Al(Mn,Fe)Si precipitates for the sample at the initial condition were similar to those subjected to two ECAP *** peak broadening measured by X-ray diffraction revealed an increment of both grain refinement and *** the second extrusion pass,the hardness increased by 62%compared with the initial ***,the heterogeneous hardness behavior was compatible with a highly localized dislocation *** two ECAP passes,shear parallel bands were observed to be at nearly 45°to the extrusion *** evaluation of first-order residual stress as a function of the depth of the analyzed sample displayed compressive or tensile values,depending on the measured *** the plastic deformation applied,the first and second-order residual stresses exhibited significant ***-Hall plots showed positive slopes,indicating an increment in the microstrain.

关键词： aluminum alloy equal-channel angular pressing texture microstructure residual stress

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Impact of liver enzymes on SARS-CoV-2 infection and the severity of clinical course of COVID-19

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liver Research 2021年第1期5卷 21-27页

作者： Fátima Higuera-de la Tijera Alfredo Servín-Caamaño Daniel reyes-Herrera Argelia Flores-lópez Enrique J.A.Robiou-Vivero Felipe Martínez-Rivera Victor Galindo-Hernández Oscar Chapa-Azuela alfonso Chávez-Morales Victor H.Rosales-Salyano Multidisciplinary Team for the Attention and Care of Patients with COVID-19 Hospital General de México Dr.Eduardo LiceagaMexico CityMexico Gastroenterology and Hepatology Department Hospital General de México Dr.Eduardo LiceagaMexico CityMexico Internal Medicine Department Hospital General de México Dr.Eduardo LiceagaMexico CityMexico Hepatobiliary and Pancreatology Clinic Surgery DepartmentHospital General de México Dr.Eduardo LiceagaMexico CityMexico Intensive Care Unit Hospital General de México Dr.Eduardo LiceagaMexico CityMexico

Background and aim Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the virus responsible for the current pandemic,can have multi-organ *** studies show that liver injury could be a manifestation of the disease,and that liver disease could also be related to a worse *** aim was to compare the characteristics of patients with severe coronavirus disease 2019(COVID-19)due to SARS-CoV-2 who required intubation versus stable hospitalized patients to identify the early biochemical predictive factors of a severe course of COVID-19 and subsequent requirement for intubation,specifically in *** This was an observational case-control study nested in a cohort *** medical records of patients admitted for confirmed COVID-19 at a tertiary level center in Mexico City were *** and biochemical data were collected,and the characteristics of patients who required invasive mechanical ventilation(IMV)(cases)were compared with stable hospitalized patients without ventilation(controls).Results We evaluated 166 patients with COVID-19 due to SARS-CoV-2 infection;114(68.7%)were men,the mean age was 50.6±13.3 years,and 27(16.3%)required *** comparative analysis between cases and controls showed(respectively)significantly lower blood oxygen saturation(SpO_(2))(73.5±12.0%vs.83.0±6.8%,Plevated alanine aminotransferase(AlT)(128(14–1123)IU/l vs.33(8–453)IU/l,P=0.003),aspartate aminotransferase(AST)(214(17–1247)vs.44(12–498)IU/l,P=0.001),lactic dehydrogenase(lDH)(764.6±401.9 IU/l vs.461.0±185.6 IU/l,P=0.001),and D-dimer(3463(524–34,227)ng/ml vs.829(152–41,923)ng/ml,P=0.003)*** in the cases group were older(58.6±12.7 years vs.49.1±12.8 years,P=0.001).Multivariate analysis showed that important factors at admission predicting the requirement for IMV during hospitalization for COVID-19 were AST≥250 IU/l(odds ratio(OR)=64.8,95%confidence interval(CI)7.5–560.3,Pl(OR=4.1,95

关键词： Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Coronavirus disease 2019(COVID-19) liver enzymes D-dimer Disease severity Invasive mechanical ventilation(IMV) Multi-organ failure

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Reservoir Processes Related to Exploitation in los Azufres (México) Geothermal Field Indicated by Geochemical and Production Monitoring Data

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International Journal of Geosciences 2015年第9期6卷 1048-1059页

作者： Víctor Manuel Arellano Rosa María Barragán Miguel Ramírez Siomara lópez alfonso Aragón Adriana Paredes Emigdio Casimiro lisette reyes Instituto de Investigaciones Eléctricas Gerencia de Geotermia Cuernavaca México Comisión Federal de Electricidad Gerencia de Proyectos Geotermoeléctricos Morelia México Comisión Federal de Electricidad Residencia Los Azufres Campamento Agua Fría México

A combined analysis of geochemical and production data of 39 wells of the los Azufres (Mexico) geothermal field (227.4 MWe) over time was developed to investigate the exploitation-related processes for 2003-2011. In the south zone, important effects of reinjection were observed through Cl increases in some wells (up to 8000 mg/kg) while in wells with significant boiling, Cl has decreased. In most of the north zone wells, the variations in gas data indicated boiling and condensation of a highly gas-depleted brine, which seems to consist of reinjection fluids. It is suggested that this process maintains the production in the zone relatively stable. The main reservoir exploitation-related processes found were: 1) production of reinjection returns;for this, it was possible to distinguish a) wells that produce liquid and steam from injection, and b) wells that produce steam from injection and sometimes condensed steam from injection;2) boiling: two types of boiling were identified: a) boiling with steam gain, and b) boiling with steam loss. The results indicated that an effective reservoir recharge occurs since very moderate production declining rates were found.

关键词： los Azufres Geothermal Field Well Simulation Fluid Geochemistry Well Bottom Conditions Production Wells

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A new oxidative pathway of nitric oxide production from oximes in plants

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Molecular Plant 2024年第1期17卷 178-198页

作者： Pedro lopez-Gomez Javier Buezo Marina Urra alfonso Cornejo Raquel Esteban Jorge Fernandez de los reyes Estibaliz Urarte Estefania Rodriguez-Dobreva Alejandro Chamizo-Ampudia Alejandro Eguaras Sebastian Wolf Daniel Marino Victor Martinez-Merino Jose F.Moran Institute for Multidisciplinary Research in Applied Biology(IMAB) Department of SciencesPublic University of Navarre(UPNA)Avda.de Pamplona 12331192 MutilvaSpain Institute for Advanced Materials and Mathematics(INAMAT2) Department of SciencesPublic University of Navarre(UPNA)Campus de Arosadia31006 PamplonaSpain Department of Plant Biology and Ecology University of the Basque Country(UPV/EHU)Sarriena s/nApdo.64448080 BilbaoSpain Center for Plant Molecular Biology(ZMBP) University of TubingenGeschwister-Scholl-Platz72074 TubingenGermany Institute of Natural Resources and Agrobiology of Salamanca(IRNASA) Department of Plant-Microorganism InteractionsSpanish National Research Council(CSIC)Cordel de Merinas40-5237008SalamancaSpain Department of Biochemistry Area of Molecular BiologyVeterinary FacultyUniversity of LeonCampus de Vegazanas/n.24071 LeonSpain

Nitric oxide(NO)is an essential reactive oxygen species and a signal molecule in *** several studies have proposed the occurrence of oxidative NO production,only reductive routes for NO production,such as the nitrate(NO_(3)^(-))-upper-reductase pathway,have been evidenced to date in land ***,plants grown axenically with ammonium as the sole source of nitrogen exhibit contents of nitrite and NO3−,evidencing the existence of a metabolic pathway for oxidative production of *** hypothesized that oximes,such as indole-3-acetaldoxime(IAOx),a precursor to indole-3-acetic acid,are intermediate oxidation products in NO *** detected the production of NO from IAOx and other oximes catalyzed by peroxidase(POD)enzyme using both 4-amino-5-methylamino-2′,7′-difluorescein fluorescence and *** stimulated the reaction,while superoxide dismutase inhibited ***,mouse NO synthase can also use IAOx to produce NO at a lower rate than *** provided a full mechanism for POD-dependent NO production from IAOx consistent with the experimental data and supported by density functional theory *** showed that the addition of IAOx to extracts from Medicago truncatula increased the in vitro production of NO,while in vivo supplementation of IAOx and other oximes increased the number of lateral roots,as shown for NO donors,and a more than 10-fold increase in IAOx dehydratase ***,we found that in vivo supplementation of IAOx increased NO production in Arabidopsis thaliana wild-type plants,while prx33-34 mutant plants,defective in POD33-34,had reduced *** data show that the release of NO by IAOx,as well as its auxinic effect,explain the superroot ***,our study reveals that plants produce NO utilizing diverse molecules such as oximes,POD,and flavins,which are widely distributed in the plant kingdom,thus introducing a long-awaited oxidative pathway to NO production in plants.T

关键词： ammonium oxidation auxin nitric oxide oxime peroxidase root phenotype

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粘接剂的不同操作流程对托槽粘接强度的影响

粘接剂的不同操作流程对托槽粘接强度的影响

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作者： alfonso Parra reyes 大连医科大学

学位级别：硕士

目的:固定矫治器在正畸治疗中应用广泛。正畸力通过固定矫治器作用于牙齿而使牙齿发生移动达成矫治目标。托槽与牙釉质的粘结问题会导致托槽脱落,延长矫治疗程,直接影响正畸治疗的疗程和效果。本研究目的在于比较相同粘结剂不同操作流程... 详细信息

目的:固定矫治器在正畸治疗中应用广泛。正畸力通过固定矫治器作用于牙齿而使牙齿发生移动达成矫治目标。托槽与牙釉质的粘结问题会导致托槽脱落,延长矫治疗程,直接影响正畸治疗的疗程和效果。本研究目的在于比较相同粘结剂不同操作流程,如牙釉质酸蚀时间延至60秒、牙釉质酸蚀处理后推迟5分钟再进行粘结时金属托槽和牙釉质之间的剪切强度(shear bond strength,SBS)和粘结剂残留指数(adhesive remnant index,ARI),进而分析临床工作中经常出现的操作变化对正畸治疗的影响,为正畸临床治疗提供参考。方法:本实验应用60颗双尖牙和两种正畸粘结系统:3M Unite?化学固化粘结系统和3M Transbond XT?光固化粘结系统进行研究,所应用酸蚀剂为Gluma Etch 35酸蚀凝胶。将符合纳入标准的60个样本随机分成两组,应用两种粘结系统进行实验。首先将两组样本置于丙烯酸树脂管中,每一组再随机分为三个亚组(每组10个样本),第I、II、III组应用3M Unite?化学固化粘结系统,第IV、V、VI组应用3M Transbond XT?光固化粘结系统。第I组和第IV组为对照组,依据粘结剂生产厂商推荐的操作规程进行粘结。第II组和第V组延长酸蚀时间至60秒,第III组和第VI组牙面酸蚀后浸泡于唾液环境中5分钟后进行粘结。剪切强度应用装载刃状边缘测试工具的langrun WDW-1型拉力试验机,将其刃状边缘置于牙齿唇面,沿托槽-粘结剂-牙齿的界面施加向根尖向的压力直至粘结剂破裂。将破裂前产生的最大压力(N)转换成压强(MPa),即为粘结剂的剪切强度。应用Photoshop CC图像处理软件分析托槽脱落后牙齿表面剩余的粘结剂,计算粘结剂残留指数。利用SPSS 22.0统计软件对所得数据进行单因素方差统计学分析。结果:本实验所得剪切强度(MPa)为:第I组:10.60±4.55,第II组:10.58±4.34,第III组:13.77±3.08,第IV组:11.89±5.44,第V组:9.18±3.27,第VI组:10.18±5.14。粘结剂残留指数为:第I组:1.50,第II组:1.50,第III组:1.20,第IV组:2.00,第V组:1.90,第VI组:1.30。对照组(第I、IV组)与实验组(第II、III、V、VI组)剪切强度及粘结剂残留指数均存在轻微差异,但无显著性差异。结论:相同粘接剂各组以及两种粘接剂间的剪切强度及粘结剂残留指数均无统计学上的差异,但3M Unite?化学固化粘结系统,牙面酸蚀后浸泡于唾液环境中5分钟后进行粘结后的剪切强度略有增加,3M Transbond XT?光固化粘结系统,延长牙釉质酸蚀时间或牙釉质酸蚀处理后延迟粘结后的剪切强度均有减小趋势,提示临床在应用Transbond XT?光固化粘结系统时,虽有足够时间调整托槽位置,但牙釉质酸蚀处理后延迟粘结托槽的时间,有可能影响托槽与牙釉质的粘结强度。

关键词：正畸治疗固定矫治器托槽粘结操作流程剪切强度粘结剂残留指

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Ar/N2/CH4 Glow Discharge at low Pressures

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Journal of Physical Science and Application 2012年第8期2卷 283-288页

作者： leomar Salazar-Flores Horacio Martinez-Valencia alfonso Guerrero-Tapia Pedro Guillermo reyes-Romero Posgrado en Ciencias Fisicas Universidad Nacional Autonoma de Mexico Avenida Universidad 1000 05000 Mdxico D.F. Mexico Instituto de Ciencias Fisieas Universidad Nacional Autonoma de Mexico Apartado postal 48-3 62251 Cuernavaca Morelos Mexico Estudiante del Posgrado de la Facultad de Ciencias Universidad Autonoma del Estado de Mexico Instituto Literario 100 Centro 50000 Toluca Estado de Mexico Mexico Facultad de Ciencias Universidad Autonoma del Estado de Mexico Instituto Literario 100 Centro 50000 Toluca Estado de Mexieo Mexico

Ar/N2/CH4 glow discharge at low-pressure are studied in a closed system. The plasma was produced in 79.6% N2-15.4% Ar- 5.0% CH4 ternary mixture at pressures between 0.5 and 10.0 Torr. The diagnostic has been made by optical emission spectroscopy （OES）. The principal species observed were： N2, N2＋, CH＋, CN, C2, C3, HI3, Ha, C＋ and At. It presents the behaviour of the bands and lines intensities as a function of the pressure. Also, it displays the ratios of intensities of N＋2 （391.44 nm）, CN （392.08 nm）, and H （486.13 nm） to that of the N2 （337.13 rim） as function of pressure. The ratios show a slow decreasing behavior as a function of the pressure. Being the CH/N2 ratio more highest and H/N2 ratio the lowest one. The variations of excited species at different pressures may change the subsequent chemical reactions in the gas phase significantly. The present results suggest that the ion-molecule and molecule-molecule reactions in the gas phase are likely to play a dominant role in the present pressures.

关键词： Glow discharge optical emission spectroscopy low pressure discharge titan's atmosphere.

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