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Effect of antimicrobial nanocomposites on Vibrio cholerae lifestyles: Pellicle biofilm, planktonic and surface-attached biofilm

ANAID MEZA VILLEZCAS (2019, [Artículo])

Vibrio cholerae is an important human pathogen causing intestinal disease with a high incidence in developing countries. V. cholerae can switch between planktonic and biofilm lifestyles. Biofilm formation is determinant for transmission, virulence and antibiotic resistance. Due to the enhanced antibiotic resistance observed by bacterial pathogens, antimicrobial nanomaterials have been used to combat infections by stopping bacterial growth and preventing biofilm formation. In this study, the effect of the nanocomposites zeolite-embedded silver (Ag), copper (Cu), or zinc (Zn) nanoparticles (NPs) was evaluated in V. cholerae planktonic cells, and in two biofilm states: pellicle biofilm (PB), formed between air-liquid interphase, and surface-attached biofilm (SB), formed at solid-liquid interfaces. Each nanocomposite type had a distinctive antimicrobial effect altering each V. cholerae lifestyles differently. The ZEO-AgNPs nanocomposite inhibited PB formation at 4 μg/ml, and prevented SB formation and eliminated planktonic cells at 8 μg/ml. In contrast, the nanocomposites ZEO-CuNPs and ZEO-ZnNPs affect V. cholerae viability but did not completely avoid bacterial growth. At transcriptional level, depending on the nanoparticles and biofilm type, nanocomposites modified the relative expression of the vpsL, rbmA and bap1, genes involved in biofilm formation. Furthermore, the relative abundance of the outer membrane proteins OmpT, OmpU, OmpA and OmpW also differs among treatments in PB and SB. This work provides a basis for further study of the nanomaterials effect at structural, genetic and proteomic levels to understand the response mechanisms of V. cholerae against metallic nanoparticles. © 2019 Meza-Villezcas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

bacterial protein, copper nanoparticle, nanocomposite, OmpT protein, OmpU protein, OmpW protein, outer membrane protein A, silver nanoparticle, unclassified drug, zeolite, zinc nanoparticle, antiinfective agent, copper, metal nanoparticle, nanocompos BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

La historia detrás de Gonolobus caamali (Apocynaceae), endémica de la península de Yucatán

GERMAN CARNEVALI FERNANDEZ CONCHA GUSTAVO ADOLFO ROMERO GONZALEZ José Luis Tapia Muñoz Ivón Mercedes Ramírez Morillo CLAUDIA JANETH RAMIREZ DIAZ William Rolando Cetzal Ix RODRIGO STEFANO DUNO KATYA JEANNETH ROMERO SOLER (2022, [Artículo])

Publicar una especie nueva para la ciencia es siempre una tarea interesante y retadora, sobre todo en los tiempos modernos, donde la comunidad de sistemáticos de plantas y las revistas científicas exigen investigaciones de biología comparada más completas, integrando diferentes fuentes de evidencia (morfológica y molecular), más allá de una simple descripción morfológica. Esta historia comenzó hace más de 15 años y terminó este año, cuando Gonolobus caamali Carnevali & R. Duno (Apocynaceae), fue descrita como una nueva especie para la ciencia. Presentamos aquí algunos detalles de esta especie.

ASCLEPIADOIDEAE EXTINCION MEXICO NOVEDAD TAXONOMICA YUCATAN BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) TAXONOMÍA VEGETAL TAXONOMÍA VEGETAL

Pioneers of modernity in Ciudad Juarez: Chapel of the Council Seminar

Leticia Peña-Barrera (2022, [Artículo, Artículo])

In this work I refer descriptively to the historical moment in which the Chapel of the Conciliar Seminary of Ciudad Juarez was built and to those who, both bishop and architect, knew how to interpret the canons of the reform of the church that was gestated to build a modern architectural icon. Recognition is given to those people who contributed, through their vision, to defining relevant buildings in the field of modernity and who were ahead of their time: the architect Oscar Sanchez Cordero, the engineer Adolfo Alvarez as a builder and Bishop Don Manuel Talamas Camandari.

architecture pioneers modernity church Ciudad Juarez arquitectura pioneros modernidad iglesia Ciudad Juárez HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA

Sustainability evaluation of contrasting milpa systems in the Yucatán Peninsula, Mexico

Santiago Lopez-Ridaura Tania Carolina Camacho Villa (2023, [Artículo])

The milpa agroecosystem is an intercropping of maize, beans, squash and other crops, developed in Mesoamerica, and its adoption is widely variable across climates and regions. An example of particular interest is the Yucatan Peninsula in Mexico, which holds highly diverse milpas, drawing on ancestral Mayan knowledge. Traditional milpas have been described as sustainable resource management models, based on long rotations within a slash-and-burn cycle in forest areas. Nevertheless, due to modernization and intensification processes, new variants of the approach have appeared. The objective of this study was to evaluate the sustainability of three milpa systems (traditional, continuous, and mechanized) in four case studies across the Peninsula, with emphasis on food self-sufficiency, social inclusion and adoption of innovations promoted by a development project. The Framework for the Evaluation of Agroecosystems using Indicators (MESMIS, for its Spanish acronym) was used for its flexible, participatory approach. A common group of indicators was developed despite regional differences between study cases, with a high level of farmer participation throughout the iterative process. The results show lower crop yields in traditional systems, but with lower inputs costs and pesticide use. In contrast, continuous milpas had higher value in terms of crop diversity, food security, social inclusion, and innovation adoption. Mechanized milpas had lower weed control costs. Profitability of cash crops and the proportion of forest were high in all systems. Highly adopted innovations across milpa types and study cases included spatial crop arrangement and the use of residues as mulches. However, most innovations are not adapted to local conditions, and do not address climate change. Further, women and youth participation is low, especially in traditional systems.

Milpa Intensification Processes Women and Youth Participation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SUSTAINABILITY INTERCROPPING FOOD SECURITY INNOVATION SOCIAL INCLUSION AGROECOSYSTEMS CASE STUDIES