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Alzheimer’s disease and type 2 diabetes mellitus:Pathophysiologic and pharmacotherapeutics links

World Journal of Diabetes 2021年第6期12卷 745-766页

作者： Milagros Rojas Mervin ch.vez-Castillo Jordan Bautista Ángel Ortega Manuel Nava Juan Salazar Edgar Díaz-Camargo osca. Medina Joselyn Rojas-Quintero Valmore Bermúdez Endocrine and Metabolic Diseases Research Center School of MedicineUniversity of ZuliaMaracaibo 4004Venezuela Universidad Simón Bolívar Facultad de Ciencias Jurídicas y SocialesCúcuta 540006Colombia Pulmonary and Critical Care Medicine Department Brigham and Women's HospitalHarvard Medical SchoolBostonMA 02155United States Universidad Simón Bolívar Facultad de Ciencias de la SaludBarranquilla 080001Colombia

At present,Alzheimer’s disease(AD)and type 2 diabetes mellitus(T2DM)are two highly prevalent disorders worldwide,especially among elderly individuals.T2DM appears to be associated with cognitive dysfunction,with a higher risk of developing neurocognitive disorders,including *** diseases have been observed to share various pathophysiological mechanisms,including alterations in insulin signaling,defects in glucose transporters(GLUTs),and mitochondrial dysfunctions in the ***,the aim of this review is to summarize the current knowledge regarding the molecular mechanisms implicated in the association of these pathologies as well as recent therapeutic *** this context,the hyperphosphorylation of tau and the formation of neurofibrillary tangles have been associated with the dysfunction of the phosphatidylinositol 3-kinase and mitogen-activated protein kinase pathways in the nervous tissues as well as the decrease in the expression of GLUT-1 and GLUT-3 in the different areas of the brain,increase in reactive oxygen species,and production of mitochondrial alterations that occur in *** findings have contributed to the implementation of overlapping pharmacological interventions based on the use of insulin and antidiabetic drugs,or,more recently,azeliragon,amylin,among others,which have shown possible beneficial effects in diabetic patients diagnosed with AD.

关键词： Alzheimer’s disease Type 2 diabetes mellitus Oxidative stress Islet amyloid polypeptide Glucagon-like peptide 1 Cognitive dysfunction Hypoglycemic agents

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Proline and Oxidative Metabolism in Young Pecan Trees Associated with Sulphate Accumulation

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Phyton-International Journal of Experimental Botany 2022年第6期91卷 1141-1152页

作者： Dalila Jacqueline Escudero-Almanza osca. Cruz-Alvarez Ofelia Adriana Hernández-Rodríguez Juan Luis Jacobo-Cuellar Esteban Sánchez-ch.vez Pablo Preciado-Rángel Dámaris Leopoldina Ojeda-Barrios Facultad de Ciencias Agrotecnológicas Universidad Autónoma de ChihuahuaChihuahua31350México Centro de Investigación en Alimentación y Desarrollo A.C.Delicias33088México InstitutoTecnologico Nacional de México-Instituto Tecnológico de Torreón Coahuila27170México

Pecan[Carya illinoinensis(Wangenh.)***.]is a deciduous tree whose fruits(nuts)are of high economic value and offer excellent nutritional ***,soils high in sulphates can limit its growth and *** with 5-year-old trees of‘Western Schley’pecan grown in soils high in sulphates,the levels of proline and oxidative metabolism were recorded in the *** showed that different levels of visible leaflet damage(‘sufficiency’,‘low’,‘moderate’or‘severe’)were associated with different levels of leaflet sulphates(mg kg^(−1)):‘sufficiency’(≤40),‘low’(41–60),‘moderate’(61–80)and‘severe’(80–100).‘Severe’sulphate damage was associated with significant reductions in chlorophyll(Tchl)(17.04μg g^(−1)),relative water content(RWC)(50%)and leaf area(LA),and with increases in the concentrations of total carotenoids(TC)and proline(Prl).Increases were also observed in the activities of the oxidative metabolism enzymes:superoxide dismutase(SOD)(1.82 units min^(−1) g^(−1)),catalase(CAT)(2.86μmol H_(2)O_(2) min^(−1) g^(−1))and antioxidant capacity(AC)(87%DPPH inhibition).However,guaiacol peroxidase(GP)showed a reduction(2.97 nmol GSH min^(−1) g^(−1)).An inverse relationship was found between the sulphate concentration in the leaflets with respect to the evaluated parameters of Tchl,TC,RWC,LA,AC,and *** synthesis and antioxidant enzymatic activity indicate salt stress in pecan leaflets in orchards irrigated with deep-well water high in sulphates.

关键词： Carya illinoinensis catalase guaiacol peroxidase salt stress photosynthetic pigments superoxide dismutase

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Public and Private Investment in the Port Sector in Mexico, 2000-2010： A Study Through Data Envelopment Analysis

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chinese Business Review 2014年第1期13卷 34-41页

作者： Odette V. Delfin-Ortega César L. Navarro-ch.vez Universidad Michoacana de San Nicolfis de Hidalgo Morelia Michoacb.n M6xico

Knowing the level of efficiency of investment applied in ports of Mexico is relevant information for the design of port policies that contribute to its development and thus to greater freight movement. The objective of this paper is to analyze the technical efficiency obtained from International Mexican Ports, through the use of the technique of Data Envelopment Analysis （DEA）. It uses data regarding public and private investment in ports applied during the period 2000-2010 and its influence on the number of Twenty-foot Equivalent Unit （TEU）. Because it has been applied the DEA-CCR （the linear programming model） model input oriented, thus not only the efficiency is calculated in ports, but benchmarking is also obtained to determine the efficient ports that serve as reference to those who were found to be inefficient. The results obtained showed that Manzanillo and Progreso were the most efficient ports. On the other hand, the ports that were not efficient for any of the years reviewed were Mazatlan and Lazaro Cardenas. Generally, public investment has been increasing over the period, and public policies are not designed to allow the ports to have an international projection.

关键词： ports investment Data Envelopment Analysis (DEA) technical efficiency

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Slope Instability on Pyroclastic Deposits: Landslide Distribution and Risk Mapping in Zacapoaxtla, Sierra Norte De Puebla, Mexico

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Journal of Mountain Science 2006年第1期3卷 1-19页

作者： Borja-Baeza R.C. Esteban-ch.vez O Marcos-López J. Pea-Garnica R.J. Alcántara-Ayala I. Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F. Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.Institute of Geography UNAM Circuito Exterior C.U. Coyoacan 04510 Mexico D.F.

In October 1999, rainfall induced landslides devastated different communities of the Sierra Norte, Puebla, causing more than 250 victims and economic losses greater than $ 450 million. The town of Zacapoaxtla was one of the sectors most affected by slope instability due to the existing geological features and geomorphic characters determined by material properties, landforms and processes. Extensive areas formed by pyroclastic piedmonts developed on the Quaternary volcanic ignimbrite deposits highly dissected by marginal gully erosion combined with an extreme rainfall event played a significant role as an ideal scenario for the occurrence of landsliding. Distribution of landslides triggered by rainfall within the main sector of the Zacapoaxtla municipality was analyzed by using IKONOS images in terms of exploring the likely relationship between mass movement incidence and levels of vegetation density. The later was undertaken by means of producing an NDVI and applying a fragmentation algorithm. Finally, a map of potential areas of mass movements risk was produced based on the combination of a socio-economic vulnerability index, geologic and geomorphological maps and the spatial landslide distribution.

关键词： Rainfall landslides IKONOS vegetation density risk Mexico

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Design and characterization of Ti6Al4V/20CoCrMo−highly porous Ti6Al4V biomedical bilayer processed by powder metallurgy

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Transactions of Nonferrous Metals Society of china 2021年第1期31卷 178-192页

作者： E.MIHALCEA H.J.VERGARA-HERNÁNDEZ O.JIMENEZ L.OLMOS J.ch.vez D.ARTEAGA División de Estudios de Posgrado e Investigación Tecnológico Nacional de México/ITMoreliaAv.Tecnológico#1500Colonia Lomas de SantiaguitoMoreliaC.P.58120México Universidad de Guadalajara DIPJoséGuadalupe Zuno#48Los BelenesZapopanC.P.45100México INICIT Universidad Michoacana de San Nicolás de HidalgoFco.J.Mujica S/NMoreliaC.P.58060México Departamento de Ingeniería Mecánica Eléctrica CUCEIUniversidad de GuadalajaraBlvd.Marcelino García Barragán 1421OlímpicaC.P.44430 GuadalajaraJaliscoMéxico Centro de Geociencias Universidad Nacional Autónoma de MéxicoBlvd.Juriquilla No.3001Querétaro 76230México

The aim of this work was to develop a Ti6Al4V/20CoCrMo−highly porous Ti6Al4V bilayer for biomedical *** powder metallurgy technique,with semi-solid state sintering as consolidation step,was employed to fabricate samples with a compact top layer and a porous bottom layer to better mimic natural *** densification behavior of the bilayer specimen was studied by dilatometry and the resulting microstructure was observed by scan electron microscopy(SEM)and computed microtomography(CMT),while the mechanical properties and corrosion resistance were evaluated by compression and potentiodynamic tests,*** results indicate that bilayer samples without cracks were obtained at the interface which has no negative impact on the *** values of the highly porous layer were in the lower range of those of human *** compression behavior is dictated by the highly porous Ti6Al4V ***,the corrosion resistance of Ti6Al4V/20CoCrMo is better than that of Ti6Al4V,which improves the performance of the bilayer *** work provides an insight into the important aspects of a bilayer fabrication by powder metallurgy and properties of Ti6Al4V/20CoCrMo−highly porous Ti6Al4V structure,which can potentially benefit the production of customized implants with improved wear performance and increased in vivo lifetime.

关键词： bilayer structure composites porosity sintering permeability compression behavior corrosion

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Optical Fiber Torsion Sensor with Mechanically Induced Long Period Fiber Gratings in Rare-Earth Doped Fibers

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Optics and Photonics Journal 2014年第6期4卷 129-135页

作者： Maria Pulido-Navarro José álvarez-ch.vez Daniel Ceballos-Herrera Ponciano Escamilla-Ambrosio Instituto Politécnico Nacional Centro de Investigación e Innovación Tecnológica (CIITEC-IPN) Mexico City Mexico Instituto Politécnico Nacional Centro de Investigación en Computación (CIC-IPN) Mexico City Mexico Universidad Autónoma de Nuevo León (UANL) Nuevo León Mexico

In this work wavelength sensitivity in mechanically induced long period fiber gratings (MLPFG) is analyzed. This analysis is first carried out both in standard single-mode fiber SMF-28 and in Er-doped fibers. The mechanical analysis for both types of fibers under different torsion conditions is presented. In order to apply the torsion one of the fiber ends is fixed while torsion is applied on the other end. A MLPFG whose period is 503 μm is used to press the fiber after torsion is applied. This allows for micro curvatures to be formed on the fiber, which in turn generates a periodical index perturbation on it. Here, it was noted that the sensitive wavelength shift of the rejection bands is bigger for Er-doped fibers. For a torsion of 6 turns applied to 10 cm of doped fiber the wavelength peaks can be moved up to 25 nm, which is longer to what was detected on standard fibers. Therefore, by using Er-doped fibers to monitor torsion on structures will give more sensitive and accurate results than using standard fibers. These results can be employed for sensing applications, especially for small to medium size structures, which can be mechanical, civil or aeronautics.

关键词： Optical Fiber Sensors Fiber Bragg Gratingsensors Torsion Sensors Rare-Earth Doped Fibers

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Unbiased Diffusion to Escape Complex Geometries: Is Reduction to Effective One-Dimensional Description Adequate to Assess Narrow Escape Times?

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Applied Mathematics 2014年第8期5卷 1218-1225页

作者： Yoshua ch.vez Guillermo chacón-Acosta Marco-Vinicio Vázquez Leonardo Dagdug Applied Mathematics and Systems Department Universidad Autónoma Metropolitana-Cuajimalpa México DF México chemistry Department Universidad Autónoma Metropolitana-Iztapalapa México DF México Physics Department Universidad Autónoma Metropolitana-Iztapalapa México DF México

This study is devoted to unbiased diffusion of point Brownian particles inside a tube of varying cross-section (see Figure 1). An expression for the mean survival time, , of the particles inside the tube is obtained in terms of the bulk diffusion constant, D0 and the system’s geometrical parameters, namely, the tube’s axial semi-length, L, the minor radius, , and the slope of the tube’s wall, . Our expression for correctly retrieves the limit behavior of the system under several conditions. We ran Monte Carlo numerical simulations to compute the mean survival time by averaging the survival time of 5 × 104 trajectories, with time step t = 10-6, D0 = 1, and L = 1. The simulations show good agreement with our model. When the geometrical parameters of this system are varied while keeping constant the tube’s enclosed volume, it resembles the problems of Narrow Escape Time (J. chem. Phys. 116(22), 9574 (2007)). A previous study on the use of the reduction to effective one-dimension technique (J. Mod. Phys. 2, 284 (2011)) in complex geometries has shown excellent agreement between the theoretical model and numerical simulations. However, in this particular system, the general assumptions of the Hill problem are seemingly inapplicable. The expression obtained shows good agreement with our simulations when 0 ≤ ≤ 1, but fails when grows larger. On the other hand, some errors are found when 0, but the expression holds reasonably well for a broad range of values of . These comparisons between simulations and theoretical predictions, and the expressions obtained for , are the main results of this work.

关键词： Component Formatting Style Styling Insert

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Physico-chemical and Microbiological Analysis of Water of the “Presa De Los Patos” in the Desierto De Los Leones National Park, Mexico

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Advances in Biological chemistry 2017年第2期7卷 122-138页

作者： Luis Raúl Gutiérrez-Lucas Luz María ch.vez-Ramírez Leticia Arregui Departamento de Ciencias Naturales DCNI Universidad Aut&oacute noma Metropolitana Unidad Cuajimalpa M&eacute xico City M&eacute xico Secretarí a de Salud Centro de Salud TI Memetla M&eacute xico City M&eacute xico

The Desierto de los Leones National Park is a place that features recreational activities for residents and visitors to Mexico City. The Presa de los Patos (Ducks Dam) is one of the many bodies of water that are present in the park. By means of physico-chemical and microbiological analysis, it was determined that the water of the Presa de los Patos cannot be considered potable. The pH range was between 5.5 - 5.9. The turbidity exceeded the values established in the standards (10.7 - 32.3 Nephelometric Turbidity Units (NTU’s)). chemical Oxygen Demand (COD) showed that large amounts of oxygen are needed to oxidize organic matter (106 - 450 mg/L). The amount of coliforms and fecal coliforms exceeds the values established by the standards used (total coliforms 98 - 956 Colony Forming Units (CFU’s), fecal coliforms 78 - 807 CFU’s). Five bacterial genera (Escherichia coli, Pseudomona, Klebsiella, Shigella and Salmonella) were isolated and identified. Most of the bacteria isolated were resistant to ampicillin (90%), while 25% were resistant to ciprofloxacin. The water consumption of the Presa de los Patos is a great risk for the habitants and visitors of the park.

关键词： Water Physico-chemical Microbiological Antimicrobial Resistance Antibiotics

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Pharmacokinetics of sildenafil in children with pulmonary arterial hypertension

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World Journal of Pediatrics 2017年第6期13卷 588-592页

作者： Hugo Juárez Olguín Hector Osnaya Martínez Carmen Flores Pérez Blanca Ramírez Mendiola Liliana Rivera Espinosa Juan Luis ch.vez Pacheco Janett Flores Pérez Ignacio Mora Maga(n)a Laboratory of Pharmacology National Institute of PediatricsMexico CityMexico Department of Pharmacology Faculty of MedicineNational Autonomous University of MexicoMexico CityMexico Service of Cardiology National Institute of PediatricsMexico CityMexico Laboratory of Pharmacology National Institute of PediatricsMexico CityMexico Subdirection of Teaching and Educational Programming National Institute of PediatricsMexico CityMexico

Background:Recently,sildenafil was introduced to treat pulmonary arterial hypertension (PAH);however,there are currently few studies on the pharmacokinetics of sildenalfil in ***,we aimed to carry out a pharmacokinetic study of sildenafil in children with PAH using a single ***:Twelve children diagnosed with PAH,consisting of with ten males and two females,were recruited for the study after obtaining written consent from their parents or *** samples were obtained predose and at 0.25,0.5,1,2,4,8 and 12 hours after the oral administration of 1 mg/kg of sildenafil using an extemporal pediatric formulation developed in our *** samples were analyzed using a previously validated high performance liquid chromatography ***:A pharmacokinetic analysis using the WinNonlin 3.1 program that considered the Akaike information criterion (AIC) for sdecting a more adjustable model was *** following pharmacokinetic parameters were obtained:maximal concentration (Cmax):366+179 ng/mL,time to maximal concentration:0.92±0.30 hours,elimination half-life (t1/2):2.41±1.18 hours,total clearance (CLto/F):5.85±2.81 L/hour,volume of distribution (Vd/F):20.13±14.5 L,absorption rate constants (Ka):0.343 hour-1,elimination rate (Ke):0.35 hour-1,area under curve from zero to infinity:2061±618 ng/mL/*** data of all patients adjusted to the model of one compartment were corroborated using ***:The parameters Ka,Ke and t1/2 were found to be similar to those reported in adults;however,the values of Cmax and Vd/F were significantly *** on these findings,we propose that treatment regimen of sildenafil be adjusted in children with PAH.

关键词： pharmacokinetics pulmonary arterial hypertension sildenafil

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Molecular Modeling of Quinoline-Based Compounds as Potential Dual Inhibitors of Reverse Transcriptase and Integrase of HIV

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Computational Molecular Bioscience 2018年第3期8卷 122-148页

作者： Alberto Cabrera Leonor Huerta Hernández Daniel ch.vez José L. Medina-Franco Departamento de Farmacia Facultad de Química Universidad Nacional Autónoma de México México City México Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México México City México Centro de Graduados e Investigación en Química del Instituto Tecnológico de Tijuana Tijuana México

As follow-up of our past publication?[1], we propose that quinolones (as part of the pyridinone family) are capable to increase the number of interactions with HIV reverse transcriptase (RT) or integrase (IN) by adding a halogen in position C-8 of aromatic portion of the quinolones. This addition could help with the activity of dual inhibitors of RT and IN. In this work, we add a chlorine atom with the rationale to identify in the docking simulations a halogen interaction with the oxygen in the near aminoacids in the binding pockets of RT and IN enzymes. Our docking studies started with RT and 320 structures. Later, we took 73 structures with good results in docking with RT. The structures that we choose contain ester or acids groups in C-3 due the structural similarity with groups in charge to interact with the Mg++ ions in Elvitegravir. In conclusion, we obtained 14 structures that could occupy the allosteric pocket of RT and could inhibit the catalytic activity of IN, for this reason could be dual inhibitors. A major perspective of this work is the synthesis and testing of the potential dual inhibitors designed.

关键词： Reverse Transcriptase Integrase Quinolone Dual Inhibitor Docking

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