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cutaneous Dengue Virus Inoculation Triggers Strong B cell Reactions but contrastingly poor T cell Responses

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Virologica Sinica 2020年第5期35卷 575-587页

作者： Edith Marcial-Juárez Julio García-cordero Raúl Antonio Maqueda-Alfaro Rafael Eduardo Saucedo-López Luvia Enid Sánchez-Torres Leticia cedillo-Barrón Leopoldo Flores-Romo Department of cell Biology Center for Advanced Research(CINVESTAV-IPN)The National Polytechnic Institute07360 Mexico CityMexico Department of Molecular Biomedicine Center for Advanced Research(CINVESTAV-IPN)The National Polytechnic Institute07360 Mexico CityMexico Immunology Department The National School of Biological Sciences(ENCB-IPN)The National Polytechnic Institute11340 Mexico CityMexico

Dengue is a global health problem without current specific treatment nor safe vaccines *** severe dengue is related to pre-existing non-neutralizing dengue virus(DENV)antibodies,the role of T cells in protection or pathology is *** cutaneous DENV infection in immunocompetent mice we previously showed the generation of pNA+germinal centers(Gcs),now we assessed the activation and proliferation of B and T cells in draining lymph nodes(DLNs).We found a drastic remodelling of DLN compartments from 7 to 14 days post-infection(dpi)with greatly enlarged B cell follicles,occupying almost half of the DLN area compared to*24%in na?ve *** clusters of proliferating(Ki-67+)cells inside B follicles were found 14 dpi,representing*33%of B cells in DLNs but only*2%in noninfected *** Gcs,we noticed an important recruitment of tingle body macrophages removing apoptotic *** contrast,the percentage of paracortex area and total T cells decreased by 14–16 dpi,compared to *** randomly distributed Ki-67+T cells were found,similar to non-infected ***69 expression by cD4+and cD8+T cells was minor,while it was remarkable in B cells,representing 1764.7%of change from basal levels 3 *** apparent lack of T cell responses cannot be attributed to apoptosis since no significant differences were observed compared to noninfected *** study shows massive B cell activation and proliferation in DLNs upon DENV *** contrast,we found very poor,almost absent cD4+and cD8+T cell responses.

关键词： Dengue virus(DENV) B and T cells proliferation Lymphocyte activation Lymph nodes In vivo cutaneous infection Immunocompetent mice

Evidence against the participation of a pharmacokinetic interaction in the protective effect of single-dose curcumin against gastrointestinal damage induced by indomethacin in rats

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Journal of Integrative Medicine 2017年第2期15卷 151-157页

作者： Liliana Zazueta-Beltran Lorena Medina-Aymerich Nadia Estela Diaz-Triste Aracely Evangelina chavez-pina GUberto castaneda-Hernandez Leticia cruz-Antonio Department of pharmacology Center for Research and Advanced Studies of the National Polytechnic Institute 07360 Mexico City Mexico Laboratory of pharmacology Institutional Program in Molecular Biomedicine National School of Medicine and Homeopathy of the National Polytechnic Institute Academic Area of Medicine of the Institute of Health Sciences 07320 Mexico City Mexico Superior Studies Faculty of Zaragoza Universidad National Autonomous of Mexico 09230 Mexico City Mexico

OBJEcTIVE： To determine the role of a pharmacokinetic interaction in the protective effect of curcumin against the gastric damage induced by indomethacin administration as such or as its prodrug acemetacin. METHODS： Wistar rats orally received single dose of indomethacin （30 mg/kg） with and without curcumin （30 mg/kg）; gastric injury was evaluated by determining the total damaged area. Additional groups of rats received an oral single dose of indomethacin （30 mg/kg） or its prodrug acemetacin （34.86 mg/kg） in the presence or absence of curcumin （30 mg/kg）. Indomethacin and acemetacin concentrations in plasma from blood draws were determined by high-performance liquid chromatography plasma concentration-against-time curves were constructed, and bioavailability parameters, maximal concentration （cmax） and area under the curve to the last sampling time （AUc0_t） were estimated. RESULTS： concomitant administration of indomethacin and curcumin resulted in a significantly reduced gastric damage compared to indomethacin alone. However, co-administration of curcumin did not produce any significant alteration in the bioavailability parameters of indomethacin and acemetacin after administration of either the active compound or the prodrug. cONcLUSION： curcumin exhibits a protective effect against indomethacin-induced gastric damage, but does not produce a reduction of the bioavailability of this nonsteroidal anti-inflammatory drug, indomethacin. Data thus suggest that a pharmacokinetic mechanism of action is not involved in curcumin gastroprotection.

关键词： indomethacin curcumin acemetacin bioavailability damage, ggastrointestinal side effect drugs, chinese herbal

computational algorithms to simulate the steel continuous casting

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 596-607页

作者： A. Ramírez-López G. Soto-cortés M. palomar-pardavé M.A. Romero-Romo R. Aguilar-López institute polytechnic national(mexico) Department of Materials Metropolitan Autonomous University

computational simulation is a very powerful tool to analyze industrial processes to reduce operating risks and improve profits from equipment. The present work describes the development of some computational algorithms based on the numerical method to create a simulator for the continuous casting process, which is the most popular method to produce steel products for metallurgical industries. The kinematics of industrial processing was computationally reproduced using subroutines logically programmed. The cast steel by each strand was calculated using an iterative method nested in the main loop. The process was repeated at each time step （？t） to calculate the casting time, simultaneously, the steel billets produced were counted and stored. The subroutines were used for creating a computational representation of a continuous casting plant （ccp） and displaying the simulation of the steel displacement through the ccp. These algorithms have been developed to create a simulator using the programming language c＋＋. Algorithms for computer animation of the continuous casting process were created using a graphical user interface （GUI）. Finally, the simulator functionality was shown and validated by comparing with the industrial information of the steel production of three casters.

关键词： continuous casting simulation numerical method computational algorithm

computational algorithms for simulating the grain structure formed on steel billets using cellular automaton and chaos theories

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 24-34页

作者： A.Ramírez-López G.Soto-cortés J.González-Trejo D.Muoz-Negrón Department of Materials Metropolitan Autonomous University institute polytechnic national institute Technologic Autonomous of mexico

The development of some computational algorithms based on cellular automaton was described to simulate the structures formed during the solidification of steel *** algorithms described take results from the steel thermal behavior and heat removal previously calculated using a simulator developed by present authors in a previous *** time is used for displaying the steel transition from liquid to mushy and *** it is also used to command computational subroutines that reproduce nucleation and grain *** routines are logically programmed using the programming language c＋＋ and are based on a simultaneous solution of numerical methods （stochastic and deterministic） to create a graphical representation of different grain structures *** grain structure obtained is displayed on the computer screen using a graphical user interface （GUI）.The chaos theory and random generation numbers are included in the algorithms to simulate the heterogeneity of grain sizes and morphologies.

关键词： continuous casting solidification grain growth algorithms computer simulation

Li2SiO3 fast microwave-assisted hydrothermal synthesis and evaluation of its water vapor and c02 absorption properties

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particuology 2016年第1期14卷 129-137页

作者： J. Ortiz-Landeros R. Lopez-Juarez I.c, Romero-Ibarra H. pfeiffer H. Balmori-Ramirez c. Gomez-Yanez Department of MetaUurgical and Materials Engineering National Polytechnic Institute ESIQIE-IPN UPALM Campus Instituto Politecnico NacionalAvenue 07738 Mexico City Mexico Materials Research institute Morelia campus National Autonomous University of Mexico Old Pdtzcuaro road 8701 58190 Morelia Michoacdn Mexico Department of chemistry Metropolitan Autonomous University Iztapalapa Campus San Rafael Atlixco Avenue 186 09340 Mexico City Mexico Materials Research institute National Autonomous University of Mexico Cd Universitaria Campus 04510 Mexico City Mexico

A series of lithium metasilicate （Li2SiO3） powder materials has been successfully synthesized by the microwave-assisted hydrothermal route using lithium hydroxide and tetraethyl-orthosilicate-derived sol precursors. ceramic powders were obtained under hydrothermal conditions of autogenous pressure in the presence of a nonionic surfactant. The production of pure and well-crystallized Li2 SiO3 using very short reaction times at low temperatures was shown by X-ray diffraction, scanning electron microscopy, and N2 adsorption-desorption analyses. Synthesized Li2SiO3 particles were nanocrystalline and exhibited different morphologies and specific surface areas depending on the synthesis conditions. Additionally, the capability of selected Li2SiO3 samples to absorb H20 and cO2 was evaluated via thermogravimet- ric analyses by varying the temperature, carrier gas, and water vapor concentration. Li2SiO3 particles exhibited interesting textural and morphological characteristics that make them suitable for use as a cO2 absorbent and which suggest that they also have the potential to be used in other applications.

关键词： cO2 capture Lithium metasilicate Hydrothermal synthesis Thermal analysis

Influence of biomass burning on ozone levels in the Megalopolis of central mexico during the cOVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso Iván Y.Hernández-paniagua institute for Atmospheric Sciences and climate change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the cOVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of central *** studied period covers the lockdown phases 2 and 3,and the first month of the New *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the pBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOc-limited regional *** contributed to increased ozone production in the middle to lower pBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in central mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： cOVID-19 mexico Megalopolis Ozone Factor Separation process Analysis

Unsupervised WSD by Finding the predominant Sense Using context as a Dynamic Thesaurus

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Journal of computer Science & Technology 2010年第5期25卷 1030-1039页

作者： Javier Tejada-carcamo Hiram calvo Alexander Gelbukh Kazuo Hara San pablo catholic University ArequipaPeru center for computing Research National Polytechnic InstituteMexico City07738Mexico Nara institute of Science and Technology TakayamaIkomaNara 630-0192Japan

We present and analyze an unsupervised method for Word Sense Disambiguation（WSD）.Our work is based on the method presented by Mccarthy et *** 2004 for finding the predominant sense of each word in the entire *** maximization algorithm allows weighted terms（similar words） from a distributional thesaurus to accumulate a score for each ambiguous word sense,i.e.,the sense with the highest score is chosen based on votes from a weighted list of terms related to the ambiguous *** list is obtained using the distributional similarity method proposed by Lin Dekang to obtain a *** the method of Mccarthy et al.,every occurrence of the ambiguous word uses the same thesaurus,regardless of the context where the ambiguous word *** method accounts for the context of a word when determining the sense of an ambiguous word by building the list of distributed similar words based on the syntactic context of the ambiguous *** obtain a top precision of 77.54%of accuracy versus 67.10%of the original method tested on *** also analyze the effect of the number of weighted terms in the tasks of finding the Most precuent Sense（MFS） and WSD,and experiment with several corpora for building the Word Space Model.

关键词： word sense disambiguation word space model semantic similarity text corpus thesaurus

Low serum levels of ghrelin are associated with gallstone disease

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World Journal of Gastroenterology 2006年第19期12卷 3096-3100页

作者： Nahum Méndez-Sánchez Guadalupe ponciano-Rodríguez Luisa Bermejo-Martínez Antonio R Villa Norberto c chávez-Tapia Daniel Zamora-Valdés Raúl pichardo-Bahena Blanca Barredo-prieto Martha H Uribe-Ramos Martha H Ramos Héctor A Baptista-González Misael Uribe Liver Unit Biomedical Research Department Medica Sur Clinic and FoundationMexico CityMexico Faculty of Medicine national Autonomous University of mexico (UNAM) Mexico CityMexico clinical Research Department national institute of perinatology Mexico CityMexico clinical Epidemiology Unit national institute of Medical Sciences and Nutrition Mexico CityMexico

AIM： To explore the role of ghrelin in gallstone disease. METHODS： We carried out a cross-sectional study in 150 subjects, 38 with gallstones （cases） and 112 controls. We also did a real-time pcR-RT study in twenty gallbladder samples each. Body mass index （BNI）, serum insulin, ghrelin, and serum lipids were measured. Logistic regression analyses （univariate and multivariate） were conducted to estimate the probability of gallstone disease associated with serum ghrelin concentrations. RESULTS： cases were statistically different from controls in gender distribution （p = 0.01）, age （53 vs 44 yr, p = 0.002）, BNI （28 vs 25; p = 0.004）, and glucose （5.26 vs 4.98 mmol/L; p = 0.05）. The prevalence of ghrelin serum levels above the third tercile was lower in subjects without metabolic syndrome （p 〈 0.05）. In a multivariate model, we found a protective effect, when ghrelin values were higher than the median value （OR = 0.27, 95%cI 0.09-0.82, p = 0.02）. Twenty （20%） gallbladder specimens expressed ghrelin mRNA. cONcLUSION： Serum ghrelin concentrations are associated with a protective effect of GD.

关键词： Gallstones Obesity Ghrelin Gallbladder Gastrointestinal hormones

Design and Implementation of a Rehabilitation Upper-limb Exoskeleton Robot controlled by cognitive and physical Interfaces

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Journal of Bionic Engineering 2022年第5期19卷 1374-1391页

作者： Arturo Gonzalez‑Mendoza Ivett Quinones‑Uriostegui Sergio Salazar‑cruz Alberto‑Isaac perez‑Sanpablo Ricardo Lopez‑Gutierrez Rogelio Lozano LAFMIA UMI Center for Research and AdvancedStudies of National Polytechnic InstituteAv.Instituto Politecnico Nacional No.250807360 Mexico CityMexico Motion Analysis Lab National Institute of Rehabilitation Luis Guillermo Ibarra IbarraCalz.Mexico Xochimilco No.28914389 Mexico CityMexico cONAcYT-cINVESTAV Av.Instituto Politecnico Nacional 250807360 Mexico CityMexico UTc-cNRS UMR Sorbonne UniversitesUTC-CNRS UMR7253 HeudiasycCompiegneFrance

This paper presents an upper limb exoskeleton that allows cognitive(through electromyography signals)and physical user interaction(through load cells sensors)for passive and active exercises that can activate neuroplasticity in the rehabilitation process of people who suffer from a neurological *** the exoskeleton to be easily accepted by patients who suffer from a neurological injury,we used the ISO9241-210:2010 as a methodology design *** the first steps of the design process,design requirements were collected from previous usability tests and ***,as a second step,a technological solution is proposed,and as a third step,the system was evaluated through performance and user *** part of the technological solution and to allow patient participation during the rehabilitation process,we have proposed a hybrid admittance control whose input is load cell or electromyography *** hybrid admittance control is intended for active therapy exercises,is easily implemented,and does not need musculoskeletal modeling to ***,electromyography signals classification models and features were evaluated to identify the best settings for the cognitive human–robot interaction.

关键词： Human Robot interaction Hybrid admittance control Surface electromyography Upper-limb exoskeletal robot