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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

Determination of mRNA Expression of Typical Proteins of Tight Junctions in the Intestinal Mucosa of Broilers (Gallus gallus domesticus)

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Open Journal of Veterinary Medicine 2021年第6期11卷 212-225页

作者： Elizabeth Aguirre garcía carlos Ignacio Soto Zárate Francisco Rodolfo González Díaz José Luis Nieto Bordes Germán Isauro Garrido Fariña carlos gerardo garcía Tovar Laboratorio 4 de Morfología Veterinaria y Biología Celular Unidad de Investigación Multidisciplinaria Facultad de Estudios Superiores Cuautitlán Universidad Nacional Autónoma de México Cuautitlán Izcalli México Laboratorio de Apoyo a Histología y Biología. Facultad de Estudios Superiores Cuautitlán Universidad Nacional Autónoma de México Cuautitlán Izcalli México

Tight junctions are mainly formed by two types of proteins;claudins and occludin, both of which are fundamental to maintain the integrity and barrier function of the intestinal epithelium. This barrier function allows for the absorption of nutrients, mainly by transcytosis;however, in birds, 90% of the substances are absorbed by paracellular mechanisms. Despite this, claudins present in the different parts of the intestinal tract of adult chickens are not known, much less their functional role. This study aimed to determine the presence of mRNA of claudins 1, 2, 3, 5, 10, 12, 16 and occludin, in the different regions of the intestine (duodenum, jejunum, ileum, cecum, and rectum) in chickens (Gallus gallus domesticus) through RT-PCR. To meet this goal, 7 weeks old roosters destined for slaughter and chicken embryos of 16 days of incubation (positive control) were used. For all the processed samples, amplicons of the expected size were obtained;claudin 1 (662 pb), claudin 2 (162 pb), claudin 3 (185 pb), claudin 5 (224 pb), claudin 10 (687 pb), claudin 12 (738 pb), claudin 16 (191 pb) and occludin (430 pb). To corroborate these findings, obtained amplicons were sequenced and, subsequently, a basic alignment was performed on the NCBI, obtaining a correlation of 100% with the original sequences in all analyzed samples. To our knowledge, the present work represents the first written report regarding the presence of mRNA of the main proteins involved in tight junction formation throughout the intestinal tract of domestic chickens of 7 weeks of age. These findings will allow elucidating the specific function of each of the reported proteins in the process of paracellular absorption in chickens.

关键词： Chicken mRNA Claudins Ocludin Tight Junctions and RT-PCR

Identification of Rhizobia Isolated from Nodules of Mexican Commercial Soybean Varieties

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American Journal of Plant Sciences 2024年第1期15卷 29-45页

作者： Cecilia Vázquez Rodríguez Lourdes Vital López Jesús gerardo garcía Olivares Homar Rene Gill Langarica Laboratorio de Biotecnología Vegetal Centro de Biotecnología Genómica Instituto Politécnico Nacional Reynosa México Carrera de Mantenimiento Industrial Universidad Tecnológica de Tamaulipas Norte Universidad Tecnológica Reynosa México

Rhizobia, crucial for nitrogen fixation in leguminous plants, play a vital role in soybean cultivation. This study, conducted in Mexico, a major soybean importer, aimed to identify bacteria from nodules of five soybean varieties in high-production regions. Multilocus sequence analysis (MLSA) was employed for enhanced species resolution. The study identified six Bradyrhizobium species: Bradyrhizobium japonicum USDA 110, Bradyrhizobium japonicum USDA 6, Bradyrhizobium elkanii USDA 76, Bradyrhizobium neotropicale, Bradyrhizobium lablabi, and Bradyrhizobium icense. Bradyrhizobium japonicum USDA 110 predominated in the soils, displaying symbiotic preference for the Huasteca 400 variety. However, phylogenetic analysis didn't reveal a clear association between strains, soil, and soybean variety. This research sheds light on the diversity of rhizobia in Mexican soybean cultivation, contributing to the understanding of symbiotic relationships in soybean production systems.

关键词： Nodules Soybean Housekeeping Genes MLSA Rhizobia Bradyrhizobium Nitrogen Fixation Symbiosis Phylogenetic Analysis

Evaluation of the Antiviral Activity of Propolis from Native Bees (Plebeia frontalis) against Canine Distemper Virus

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Open Journal of Veterinary Medicine 2020年第12期10卷 207-218页

作者： Olga Valeria Domínguez Jiménez Betsabé Rodríguez Pérez Tonatiuh Alejandro Cruz Sánchez carlos gerardo garcía Tovar José Luis Nieto Bordes carlos Ignacio Soto Zárate Laboratorio 4 de Morfología Veterinaria y Biología Celular Unidad de Investigación Multidisciplinaria (UIM) Facultad de Estudios Superiores Cuautitlán UNAM Cuautitlán Izcalli México Laboratorio 6 de Bioprospección Microbiológica Unidad de Investigación Multidisciplinaria (UIM) Facultad de Estudios Superiores Cuautitlán UNAM Cuautitlán Izcalli México

Propolis is a natural substance made from resins collected from trees and plants, and which bees combine with pollen, wax, and their own enzymes. It has a complex chemical composition that varies with the harvest season, vegetation type, bee species, and geographical region. Thanks to its components, it has valuable biological properties such as antifungal, antibacterial, anticancer, antiviral, and immunomodulatory activity. For this study, a sample of propolis harvested in April 2019 was used, which came from a bee native to Mexico (Plebeia frontalis) in whose geographical environment there are seven other native species. Canine distemper virus is an RNA virus that causes a systemic infection with high fatality rates in guests without protective immunity. In this work, the antiviral effect of Plebeia frontalis propolis on canine distemper virus was tested, administering it one hour before and simultaneously to infection. The antiviral effect was evaluated by determining cellular viability with the MTT assay. The results obtained show that this propolis has a statistically significant antiviral effect on both treatments, although it is slightly better when applied one hour before viral infection, so we can recommend it as an antiviral treatment in both domestic animals and human beings. There are currently few studies of the antiviral effect of propolis, this being the first study of a melliponium propolis in veterinary medicine.

关键词： Propolis Vero Cells Antiviral Effect Meliponines

Evaluation of Changes in Actin Filaments of RK13 Cells Infected with Malassezia pachydermatis

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Open Journal of Veterinary Medicine 2018年第2期8卷 15-24页

作者： Iris del Socorro Flores Rodríguez Tonatiuh Alejandro Cruz Sánchez José Luis Nieto Bordes Francisco Rodolfo González Díaz carlos Ignacio Soto Zárate carlos gerardo garcía Tovar Laboratorio 6 de Bioprospección Microbiológica Unidad de Investigación Multidisciplinaria (UIM) Facultad de Estudios Superiores Cuautitlán UNAM Cuautitlán Izcallí México Laboratorio 4 de Morfología Veterinaria y Biología Celular Unidad de Investigación Multidisciplinaria (UIM) Facultad de Estudios Superiores Cuautitlán UNAM Cuautitlán Izcallí México

Background: Malassezia pachydermatis is the main causative agent of canine otitis and also of a myriad of dermatological problems in companion animals;its interaction mechanisms with host cells are still unclear. Objectives: To establish an in vitro infection model of M. pachydermatis-exposed RK13 cells in order to evaluate cell morphological changes as well as changes in the structure of actin filaments. Methods: Cultures of RK13 cells were infected with M. pachydermatis, alterations caused by the yeast were evaluated by optical and fluorescence microscopy. Results: M. pachydermatis adheres itself to the cell and produces the formation of multiple agglomerates that cause changes in cell morphology, formation of cell aggregates in overlays, presence of syncytia and destruction of cell culture structure. The damaged cells presented changes in the actin filaments consisting of thickening of the cell cortex and loss of stress fibers. On the other hand, the formation of perinuclear actin rings in the yeasts was observed. Conclusions: An in vitro infection model was established with M. pachydermatis and alterations in cell morphology were observed consisting of changes in the structure of the actin filaments, overgrowth of the cells and the presence of syncytia.

关键词： Malassezia pachydermatis RK13 Cells Actin Filaments

Gut microbiota in preterm infants receiving breast milk or mixed feeding

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World Journal of Clinical Pediatrics 2024年第2期13卷 135-145页

作者： Sandra Gabriela Sánchez-González Bárbara Gabriela Cárdenas-del-Castillo Elvira Garza-González gerardo R Padilla-Rivas Isaías Rodríguez-Balderrama Consuelo Treviño-Garza Fernando Félix Montes-Tapia gerardo C Palacios-Saucedo Anthony Gutiérrez-Rodríguez Manuel Enrique de-la-O-Cavazos Department of Pediatrics Hospital Universitario“Dr.JoséEleuterio González”Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Departamento de Bioquímica y Medicina Molecular Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Department of Biochemistry and Molecular Medicine Universidad Autónoma de Nuevo LeónMonterrey 64460Nuevo LeónMéxico Department of Pediatric Surgery Hospital Universitario"Dr.JoséEleuterio González"Monterrey 64460Nuevo LeónMéxico

BACKGROUND Preterm birth is the leading cause of mortality in newborns,with very-low-birthweight infants usually experiencing several *** milk is considered the gold standard of nutrition,especially for preterm infants with delayed gut colonization,because it contains beneficial microorganisms,such as Lactobacilli and *** To analyze the gut microbiota of breastfed preterm infants with a birth weight of 1500 g or *** An observational study was performed on preterm infants with up to 36.6 wk of gestation and a birth weight of 1500 g or less,born at the University Hospital ***éEleuterio González at Monterrey,Mexico.A total of 40 preterm neonates were classified into breast milk feeding(BM)and mixed feeding(MF)groups(21 in the BM group and 19 in the MF group),from October 2017 to June *** samples were collected before they were introduced to any feeding *** full enteral feeding was achieved,the composition of the gut microbiota was analyzed using 16S rRNA gene *** variables were compared using Student’s t-test or using the Mann–Whitney U test for nonparametric ***,evenness,equitability,Margalef’s index,Fisher’s alpha,Chao-1 index,and Shannon’s diversity index were also *** No significant differences were observed at the genus level between the *** comparison indicated higher counts of Alphaproteobacteria and Betaproteobacteria in the initial compared to the final sample of the BM group(P<0.011).In addition,higher counts of Gammaproteobacteria were detected in the final than in the initial sample(P=0.040).According to the Margalef index,Fisher’s alpha,and Chao-1 index,a decrease in species richness from the initial to the final sample,regardless of the feeding type,was observed(P<0.050).The four predominant phyla were Bacteroidetes,Actinobacteria,Firmicutes,and Proteobacteria,with Proteobacteria being the most ***,no significant differences were

关键词： Gut microbiota Human milk Preterm infant Proteobacteria Very low birth weight 16S rRNA

Efficacy and safety of abrocitinib in Chinese patients with moderate-to-severe atopic dermatitis: A post hoc analysis of the JADE REGIMEN phase 3 trial

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中华医学杂志(英文版) 2024年第16期137卷 2024 Jul 15页

作者： Li Hang Cheng Hao Lu Qianjin Lai Wei Tao Xiaohua Encinas gerardo A. Vyas Shefali Wang Bo Luo Xin Li Shiqi Department of Dermatology Peking University First Hospital National Clinical Research Center for Skin and Immune Diseases Beijing China Department of Dermatology Sir Run Run Shaw Hospital Zhejiang University School of Medicine Hangzhou Zhejiang China Department of Dermatology The Second Xiangya Hospital of Central South University Changsha Hunan China Department of Dermatology The Third Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong China Department of Dermatology Zhejiang Provincial People’s Hospital Hangzhou Medical College Hangzhou Zhejiang China Pfizer S.A. de C.V. Mexico City Mexico Pfizer Inc. New York NY USA Pfizer Investment Co. Ltd Beijing China Pfizer (China) R& D Co. Ltd Shanghai China Pfizer PBG Shanghai China

Influence of parameters on the microstructure of a duplex stainless steel joint welded by a GMAW welding process

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Progress in Natural Science:Materials International 2022年第4期32卷 415-423页

作者： Sandra Chacón-Fernández Antonio Portolés garcía gerardo Romaní Labanda Universidad Politécnica de Madrid Escuela Técnica Superior de Ingenieros Industriales UPM

Duplex stainless steels（DSSs） are widely used in industry for their desirable properties. Any fusion welding technique modifies the microstructure and, consequently, the properties of the material. This paper presents a parametric study of the variables that determine the energy contribution（current, voltage and welding speed） and the structural modifications produced during gas metal arc welding. The analysis comprises metallographic study,phase balance, dimensioning of the weld beads and tensile and hardness tests. The influence of the variables studied on the thermal cycles obtained（temperatures reached and cooling rate） was determined by using a finite element model. The results showed that, in addition to the indicated parameters, the parameter power transfer per volume（W/m3） and the geometry in the bead must be controlled due to their influence on the heat flow distribution and phase balance.

关键词： Welding Heat input GMAW Duplex stainless steels (DSS) Finite element model (FEM)

A Systematic Review of Cannabidiol Effects in Coronary Syndromes: Challenges to Clinical Translation

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Journal of Biosciences and Medicines 2024年第4期12卷 246-263页

作者： Mario E. Zuñiga-Ayala Alejandra Meaney-Martínez Alejandro Alcocer-Chauvet Vidal Gonzalez-Coronado Nestor Rubio-Infante gerardo garcia-Rivas Department of Cardiology Instituto de Seguridad Social and Trabajadores del Estado (ISSSTE) Hospital Regional Primero de Octubre Mexico City Mexico Department of Interventional Cardiology Instituto de Seguridad Social y Trabajadores del Estado (ISSSTE) Hospital Regional Primero de Octubre Mexico City Mexico Instituto Tecnó logico de Monerrey Escuela de Medicina and Ciencias de la Salud C&#225tedra de Cardiolog&#237a and Medicina Vascular Monterrey Mexico

Background: Myocardial ischemia in addition to other several cardiac syndromes represent a pathological proinflammatory state alongside a complex cellular microenvironment that can be modified by using cannabinoids. Cannabidiol (CBD), a non-psychoactive compound of cannabis has been recently proposed as an immudomodulatory and cardioprotective drug. Objectives: In this systematic review we sought to clarify and summarize the clinical and preclinical evidence of potential benefit of the use of CBD in coronary syndromes. Methods: We conducted a systematic search and review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Review of Animal Data from Experimental Studies (CAMARADES) guidelines, in the electronic database from PubMed, Web of Science and Scopus up to April 2022 using predefined search terms. Pre-specified exclusion and inclusion criteria were considered, finally 11 articles were chosen to be included for this peer review. Results: Currently there are no good-quality clinical trials with the use of CBD in acute or chronic coronary syndromes. A total of 11 preclinical studies where prescreened and 5 demonstrated reproducible positive cardiovascular outcomes on in-vivo models treated with CBD. Mechanisms of CBD cardioprotection observed: 1) reduction in oxidative stress and inflammation, 2) activation of adenosine receptors and 3) increased expression of angiotensin type 2-receptor. Experimental models included ischemia/reperfusion injury, myocardial infarction, arrhythmias, and metabolic syndrome-like conditions. Conclusion: No clinical recommendation can be issued with the current evidence, on the use of CBD in acute and chronic coronary syndromes. Based on preclinical evidence, we considered there is enough evidence to propose the development of well-designed clinical trials that include CBD in the management of coronary syndromes.

关键词： Cannabis Cannabidiol Acute Coronary Syndromes Myocardial Infarction Myocardial Ischemia and Oxidative Stress