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Loss of T-cell protein tyrosine phosphatase in the intestinal epithelium promotes local inflammation by increasing colonic stem cell proliferation

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Cellular & Molecular Immunology 2018年第4期15卷 367-376页

作者： Stéphanie Bussières-Marmen Valérie Vinette Jeremy Gungabeesoon Isabelle Aubry Luis alberto pérez-Quintero Michel L Tremblay Department of Biochemistry McGill UniversityMontréalQuébecCanada Rosalind and Morris Goodman Cancer Research Centre MontréalQuébecCanada Department of Microbiology and Immunology McGill UniversityMontréalQuébecCanada

T-cell protein tyrosine phosphatase(TC-pTp)has a critical role in the development of the immune system and has been identified as a negative regulator of ***-nucleotide polymorphisms in the TC-pTp locus have been associated with increased susceptibility to inflammatory bowel diseases(IBDs)in *** further understand how TC-pTp is related to IBDs,we investigated the role of TC-pTp in maintaining the intestinal epithelial barrier using an in vivo genetic *** epithelial cell(IEC)-specific deletion of TC-pTp was achieved in a mouse model at steady state and in the context of dextran sulphate sodium(DSS)-induced ***(KO)of TC-pTp in IECs did not result in an altered intestinal ***,upon DSS treatment,IECspecific TC-pTp KO mice displayed a more severe colitis phenotype with a corresponding increase in the immune response and inflammatory cytokine *** absence of TC-pTp caused an altered turnover of IECs,which is further explained by the role of the tyrosine phosphatase in colonic stem cell(CoSC)*** results suggest a novel role for TC-pTp in regulating the homeostasis of CoSC *** supports the protective function of TC-pTp against IBDs,independently of its previously demonstrated role in intestinal immunity.

关键词： Colonic stem cells DSS-induced colitis intestinal epithelial barrier TC-pTp

Toxicity of Mexican native plant extracts against larvae of Aedes aegypti(Diptera: Culicidae)

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Asian pacific Journal of Tropical Biomedicine 2015年第4期5卷 287-291页

作者： Rosario Ruiz-Guerrero Mario alberto Rodríguez-pérez Mariano Norzagaray-Campos CIITEC-IpN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco Centro de Biotecnología Genómica-IpN Blvd. Del Maestro S/N Colonia Narciso Mendoza CIIDIR-IpN-Sinaloa Bulevar Juan de Dios Bátiz Paredes No 250 Colonia San Joachin. Guasave

Objective: To evaluate five indigenous Mexican plants [Hippocratea excelsa, Hippocratea celastroides, Argemone mexicana(A. mexicana), Tagetes lucida, and pseudosmodingium perniciosum(p. perniciosum)] toxicity against the fourth instar larvae of the dengue primary vector, Aedes aegypti(A. aegypti).Methods: Each plant part was treated successively with hexane, ethyl acetate, acetone, and methanol to extract potential active components of the plants against the dengue ***: There was a range of toxicity at 24 or 48 h post-exposure for the different plant parts and organic solvent used(LC50 values ranged between 20 and 890 μg/mL). Extracts from seeds of A. mexicana(hexane washing with methanol and acetone) and stem-bark of p. perniciosum(hexane) showed highest toxicity to Ae. aegypti larvae at 48 h post-exposure(LC50 values were80, 50, and 20 μg/mL, respectively), thus making them potential candidates as *** are on-going to characterize the bioactive components of the extracts, through chromatography, for their use as biological tools for the control of the primary dengue ***: A. mexicana and p. perniciosum are good candidates to combat the dengue vector, Ae. aegypti, as they were highly toxic to the larvae.

关键词： Aedes aegypti Dengue Larvicidal activity plant organic extracts

New Evidence on Rotational Dynamics

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World Journal of Mechanics 2013年第3期3卷 174-177页

作者： Luis alberto pérez Curiosity & Intuition for Understanding and Knowledge Valladolid Spain

In this paper, the author confirmed a new theory to explain the mechanical behavior of macroscopic bodies. The confirmed hypothesis is the Theory of Dynamics Interaction by the professor Gabriel Barceló. Barceló explained his theory in an article called “Analysis of Dynamics Fields in Noninertial Systems”, World Journal of Mechanics, Vol. 2, No. 3, 2012, pp. 175-180. This hypothesis holds that the mechanical behavior of macroscopic bodies in a non-inertial environment opens new assumptions on inertial fields and rotational dynamics. An associated experiment was presented to support the discussion in the paper. The author first became aware of the proposals of professor Gabriel Barceló’s Theory of Dynamics Interaction through his 2006 article on Saturn planet rings, which suggested unsolved phenomena in rotational dynamics and the inception of a novel theory [1]. Intuitively, the author realized himself about the fact that the cosmos is mechanical from its smallest to its widest comprehensible appreciation. If material behavior is mechanical everywhere and every time, from a subatomic particle, wave or string, to a cluster of galaxies, then our understandable solutions must comply with the Laws of Motion, it could be believed.

关键词： Rotational Dynamics Field Theory Superposition of Simultaneous Motions Macroscopic Bodies Mechanics Inertial Fields Torque Angular Momentum

Erosion problem in tool steel using cold box core-making process

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China Foundry 2019年第3期16卷 204-210页

作者： Eduardo Rodríguez alberto pérez Rafael David Mercado-Solis Velasco-Téllez Abraham Omar Jimenez Martin Flores Marco Aurelio Gonzalez Jesus Ibarra Universidad de Guadalajara Departamento de Ingeniería de Proyectos/CUCEI CONACyT México Facultad de Ingeniería Mecánica y Eléctrica UANL México Nemak México S.A. García México Instituto Tecnológico José Mario Molina pasquel y Henríquez Unidad Zapopan México

This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows:(i) The harder material, the lower erosion;(ii) the maximum erosion rate is at 30°;(iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level;(iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles.

关键词： erosion cold box core-making H13 tool steel resin coated silica sand

Subclinical carotid atherosclerosis predicts all-cause mortality and cardiovascular events in obese patients with negative exercise echocardiography

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World Journal of Cardiology 2019年第1期11卷 24-36页

作者： Rafael Vidal-perez Raúl Franco-Gutiérrez alberto J pérez-pérez Virginia Franco-Gutiérrez alberto Gascón-Vázquez Andrea López-López Ana María Testa-Fernández Carlos González-Juanatey Department of Cardiology Hospital Universitario Lucus Augusti Department of Otolaryngology Hospital Carmen y Severo Ochoa Faculty of Medicine University of Santiago de Compostela

BACKGROUND Obesity is a major health problem due to its high prevalence. The relationship between obesity and cardiovascular disease is unclear. Some studies agree that certain conditions associated with obesity, such as physical inactivity or cardiovascular risk factors, are responsible for cardiovascular risk excess among obese people. Carotid intima-media thickness and carotid plaques(Cp) have been associated with cardiovascular adverse events in healthy populations, and recent data suggest a higher prevalence of subclinical carotid atherosclerosis in obese and metabolically unhealthy patients. However, there are no studies correlating subclinical atherosclerosis and adverse events(AE) in obese *** To determine the association between carotid disease and AE in obese patients with negative exercise echocardiography(EE).METHODS From January 1, 2006 to December 31, 2010, 2000 consecutive patients with a suspicion of coronary artery disease were submitted for EE and carotid ultrasonography. Exclusion criteria included previous vascular disease, left ventricular ejection fraction positive EE, significant valvular heart disease and inferior to submaximal EE. An AE was defined as all-cause mortality,myocardial infarction and cerebrovascular accident. Subclinical atherosclerosis was defined as Cp presence according to Manheim and the American Society of Echocardiography *** Of the 652 patients who fulfilled the inclusion criteria, 226(34.7%) had body mass indexes ≥ 30 kg/m2, and 76 of them(33.6%) had Cp. During a mean follow-up time of 8.2(2.1) years, 27 AE were found(11.9%). Mean event-free survival at 1, 5 and 10 years was 99.1%(0.6), 95.1%(1.4) and 86.5%(2.7), respectively. In univariate analysis, Cp predicted AE [hazard ratio(HR) 2.52, 95% confidence interval(CI) 1.17-5.46; p = 0.019]. In multivariable analysis, the presence of Cp remained a predictor of AE(HR 2.26, 95%CI 1.04-4.95, p = 0.041). Other predictors identified were glomerular

关键词： Carotid intima media thickness Carotid plaque Carotid disease Myocardial infarction Mortality Stroke Exercise stress echocardiography

Implementing p-15/ABM Bone Graft as a Standardized Technique for Lumbar Fusion Approaches

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Open Journal of Modern Neurosurgery 2024年第4期14卷 256-266页

作者： Diana Chávez Lizárraga Jesús alberto pérez Contreras Emmanuel Cantú Chávez Ana Sofía peña Blesa Angeles del pedregal Hospital Ciudad de Mxico Mxico

Introduction: Lumbar fusion as low back pain treatment continues to be a challenge because of the multiple techniques and materials available, most popular techniques include Transforaminal lumbar interbody fusion (TLIF), Lateral lumbar interbody fusion (LLIF) and Anterior lumbar interbody fusion (ALIF). Successful lumbar fusion is associated with better clinical outcomes, and it is enhanced and targeted through the use of bone graft materials as an osteogenic cell binding peptide p-15, bound to an anorganic bone mineral (ABM). This peptide improves bone formation when used in fixation devices in a targeted and limited way to the implant surface by activating osteoblast precursor cells;by the osteogenic, osteoinductive and osteoconductive stimuli. The main objective of this study is to standardize the lumbar fusion process in the 3 techniques and achieve a more efficient and predictable lumbar fusion, evaluating results with radiological and clinical scales. Material and Methods: patients underwent lumbar fusion with the use of p-15 Osteogenic Cell Binding peptide, bound to an anorganic bone mineral (p-15/ABM) bone graft (5 cc) in three different techniques (TLIF, LLIF, ALIF), achieving a total of 100 lumbar levels. Radiological outcomes included fusion rates per Hounsfield Units at computed tomography (CT) scan and Lenke scale. Clinical outcomes were evaluated via the Oswestry Disability Index (ODI), Short Form performance (SpF-36) and Visual Analog Scale (VAS and VASs) for pain and satisfaction. Results: 67 patients completed the 12 months follow-up, showing no differences in fusion rates between techniques. (Computed Tomography Hounsfield Units) CTHU reaches more than 200 UH at 3 months follow-up and continues fusion process till 12-month follow-up. Clinical scales showed no disability at ODI, improvement at VAS and VASs scales, absence of health restrictions at SpF-36 score since 6 months follow up. Conclusion: Bone graft volume of 5 cc is adequate for achieving

关键词： Lumbar Fusion Spine Surgery Bone Graft peptide p-15

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电场作用下气-液两相界面线性失稳数值分析

电场作用下气-液两相界面线性失稳数值分析

Uncompensated Centrifugal Flow about Accelerated Cosmic Expansion

第十一届全国流体力学学术会议

作者：刘强 alberto T.pérez 吴健哈尔滨工业大学能源科学与工程学院 Universidad de Sevilla Departamento de Electrónica y Electromagnetismo

本文针对一类直流电场作用下的气-液两相界面失稳问题开展了数值方法开发以及基于数值解的稳定性分析。如图1所示,在平行电极板之间存在着一定厚度的液体层与气体层,与气体层接触的上极板在处于高电势的同时存在电荷注入。初始阶段,两... 详细信息

本文针对一类直流电场作用下的气-液两相界面失稳问题开展了数值方法开发以及基于数值解的稳定性分析。如图1所示,在平行电极板之间存在着一定厚度的液体层与气体层,与气体层接触的上极板在处于高电势的同时存在电荷注入。初始阶段,两相界面在电场力、粘性力与表面张力的共同作用下保持平衡,随着电场强度的增加,电场力将驱动两相流体发生流动,引起界面的失稳。针对此问题,我们基于开源计算流体动力学软件包OpenFOAM开发了一种气液两相电流体动力学数值模拟算法。该算法使用流体体积法(Volume Of Fluid,VOF)对两相系统进行建模,在自由电荷的输运中考虑了电荷的注入,成功地在两相系统中耦合了电场和流场的计算。之后,本文通过静电平衡算例评估了算法中电场方程的求解精度,通过电对流算例考察了电场方程与流场方程耦合计算的效果,初步验证了本算法处理气液两相电流体动力学问题的可行性。采用上述数值算法,本文对图1中的气液两相系统进行了数值模拟。模拟得到的对流单元(如图2所示)尺寸与线性稳定性分析得到的临界失稳半波长一致,临界失稳驱动参数也与线性稳定性分析的结果接近。结合系统失稳时的流场特征,我们对气液界面的失稳机理进行了解释,阐明了单相区内的流动对于气液两相界面稳定性的影响。

关键词：电流体动力学气-液两相流流体体积法数值模拟稳定性

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Standardizing MI-TLIF, a proposal for a Reproducible Technique

World Journal of Mechanics 2021年第4期

作者： Luis alberto pérez pérez

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Open Journal of Modern Neurosurgery 2024年第2期14卷 91-103页

作者： Iván Ulises Sámano López Jesús alberto pérez Contreras Emmanuel Cantú Chávez Diana Chávez Lizárraga Ana Sofía peña Blesa Thania Karina Gutiérrez Anchondo Á ngeles Pedregal Ciudad de México México

Background: Minimally invasive transforaminal lumbar interbody fusion (MI TLIF) is a widely known and performed technique, however its versatility among different physicians continues to hinder its replication and results. Therefore, this study aimed to provide a step-by-step surgical guide to perform a safe MI-TLIF, based on the results obtained in patients operated on by a single surgeon over a period of 12 years. patients and methods: A retrospective, single center, longitudinal, and observational cohort study was conducted with 931 patients who underwent MI TLIF by a single surgeon between 2010 and 2022 using the technique described on this paper, each with a minimum follow-up of 12 months. Criteria included Schizas classification, listhesis according to Meyerding classification, number of levels treated, cage size, and complications (screw repositioning or cerebrospinal fluid leak). patient clinical outcomes were assessed using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) for pre- and postoperative radicular pain. Thin slice CT scans were used to assess the progression of the fusion using the Bridwell classification. In the statistical analysis, percentages, median, and interquartile range (IQR) were calculated. Results: Nine hundred and thirty one patients underwent MI TLIF using the technique described, eight hundred and eighty (94.5%) had a single level treated and fifty one (5.5%) had a 2 level procedure (982 levels), an 8mm cage was placed on five hundred and seventeenlevels (52.7%), six hundred and sixty three levels(67.6%) achieved grade I fusion, two hundred and sixty six levels (27.1%) achieved grade II fusion, 52 levels (5.3) achieved grade III fusion and one level (0.1) achieved a grade IV fusion or non-union. Revision surgery was performed on 3 patients (0.3%) for screw repositioning, cerebrospinal fluid leak was present on 2 patients during surgery and treated before closure. VAS scores and ODI were improved at 12 months postop (V

关键词： MITLIF Lumbar Interbody Fusion Technique pain Relief and Disability