Composición espacial y temporal de aves acuáticas y rapaces en humedales del centro de México

Introduction: Wetlands play an important role as habitats for various groups of birds, particularly those with aquatic habits. Despite their high biodiversity, in Mexico there are few studies on the composition and dynamics of bird assemblages in these wetlands. Objective: To evaluate the spatial and temporal dynamics of the aquatic bird and raptor community in wetlands. Methods: To characterize waterfowl and raptors, transects of variable distance were checked monthly from November 2019 to February 2022 in wetlands located in the Metropolitan Zone of Mexico City. Results: We counted 105 bird species. The highest values of diversity were in Laguna de Zumpango (91 species) and Lake Nabor Carrillo (91). Most of these species are migratory (63%), while 30% are residents, and 7% are introduced. Significant spatial and temporal differences (p<0,05) were found in the composition of the bird community. Conclusion: The highest diversity was in Zumpango and Nabor, and most species are migratory.Introducción: Los humedales cumplen una importante función ecológica como hábitats para diversos grupos de aves, en específico las de hábitos acuáticos. A pesar de su alta diversidad, en México existen escasos estudios sobre la composición y dinámica de la comunidad de aves en humedales. Objetivo: evaluar la dinámica espacial y temporal de la comunidad de aves acuáticas y rapaces en humedales. Métodos: para caracterizar las aves acuáticas y rapaces se realizaron transectos de distancia variable mensualmente durante noviembre de 2019 a febrero de 2022 humedales ubicados en la Zona Metropolitana de la Ciudad de México. Resultados: se registraron un total de 105 especies de aves. Los valores más altos de diversidad se encontraron en la Laguna de Zumpango (91 especies) y en el Lago Nabor Carrillo (91). La mayoría de estas especies son migratorias (63%), mientras que 30% son residentes, y 7% son introducidas. Se encontraron diferencias espaciales y temporales significativas (p<0,05) en la composición de la comunidad de aves. Conclusión: La mayor diversidad fue en Zumpango y Nabor Carrillo, y la mayoría fueron especies migratorias

Cellulose-Chitosan-Nanohydroxyapatite Hybrid Composites by One-Pot Synthesis for Biomedical Applications

The development of organic–inorganic hybrid materials deserves special interest for bone tissue engineering applications, where materials must have properties that induce the survival and activation of cells derived from the mesenchyme. In this work, four bio-nanocomposites based on cellulose and variable content of chitosan, from 15 to 50 w% based on cellulose, with nanohydroxyapatite and β-Glycerophosphate as cross-linking agent were synthesized by simplified and low-energy-demanding solvent exchange method to determine the best ratio of chitosan to cellulose matrix. This study analyzes the metabolic activity and survival of human dermal fibroblast cells cultivated in four bio-nanocomposites based on cellulose and the variable content of chitosan. The biocompatibility was tested by the in vitro cytotoxicity assays Live/Dead and PrestoBlue. In addition, the composites were characterized by FTIR, XRD and SEM. The results have shown that the vibration bands of β-Glycerophosphate have prevailed over the other components bands, while new diffraction planes have emerged from the interaction between the cross-linking agent and the biopolymers. The bio-nanocomposite micrographs have shown no surface porosity as purposely designed. On the other hand, cell death and detachment were observed when the composites of 1 and 0.1 w/v% were used. However, the composite containing 10 w% chitosan, against the sum of cellulose and β-Glycerophosphate, has shown less cell death and detachment when used at 0.01 w/v%, making it suitable for more in vitro studies in bone tissue engineering, as a promising economical biomaterial

Evaluation of gamma diversity of reef corals (Scleractinia) in the Mexican Pacific Evaluación de la diversidad gama de corales arrecifales (Scleractinia) en el Pacífico de México

In order to assess gamma diversity of hermatypic corals, maximum likelihood methods (Chao, Jacknife) and resampling (bootstrap) were used over a database with 3 423 records of corals from 15 regions of the Mexican Pacific. Analysis were conducted for the species richness (34 species) and for the 5 families reported. Results suggest that species richness might be underestimated up to 25% as well as for the families Pocilloporidae, Poritidae, and Agariciidae. On the other hand, richness observed for Siderastreidae and Fungiidae is not significantly different from expected. According to rare species distribution and historical records in the Mexican Pacific, it is expected that new records will come either from the Revillagigedo, southern region of the Baja California Peninsula or adjacent mainland (Sonora) and Oaxaca coast. This kind of analysis is fundamental in order to optimize sampling efforts and to establish marine protected areas that protect known and potential species richness.<br>Con el fin de evaluar el conocimiento de la diversidad regional de corales zooxantelados, se aplicaron métodos de máxima verosimilitud (chao, jacknife) y remuestreo (bootstrap) sobre una base de datos de 3 423 registros, ordenada en 15 áreas geográficas del Pacífico mexicano. Los análisis se hicieron para la riqueza específica total (34 especies) y las 5 familias de corales conocidas y se contrastaron con los valores esperados, considerando todas las especies reportadas para el Pacífico oriental. La riqueza conocida de especies de corales zooxantelados posiblemente esté subestimada hasta en un 25%, al igual que en el caso de las familias Pocilloporidae, Poritidae y Agariciidae, mientras que para Siderastreidae y Fungiidae no hay diferencias entre los valores esperados y los observados. Considerando el área de distribución de las especies raras en el litoral oeste de México y el historial de registros, se sugiere que las próximas especies a encontrarse posiblemente aparezcan en la zona de las islas Revillagigedo, en la parte sur de la península de Baja California o la zona continental adyacente (Sonora) y en las costas de Oaxaca. Este tipo de análisis son fundamentales para la optimización del esfuerzo de muestreo y para el establecimiento de áreas naturales protegidas que salvaguarden la biodiversidad conocida y potencial

Inhibitory effects of lupene-derived pentacyclic triterpenoids from Bursera simaruba on HSV-1 and HSV-2 in vitro replication

The cytotoxicity and antiviral properties of Bursera simaruba against herpes simplex viruses (HSV-1 and HSV-2) were investigated through a bioactivity-guided isolation protocol. The plant material was fractionated using solvent-solvent partitioning, size-exclusion and thin-layer chromatography. The antiviral compounds present in the most active fractions were identified by means of LC-MS and NMR. Three different methods were compared during the evaluation of antiviral activity of samples. Four lupene-related pentacyclic triterpenes were found to be responsible for the anti-herpesvirus effects of B. simaruba and were isolated from this species for the first time. The selective indexes (SI) of B. simaruba-derived samples ranged from 7.7 to 201.9

Differential adhesion and fibrinolytic activity of mesenchymal stem cells from human bone marrow, placenta, and Wharton’s jelly cultured in a fibrin hydrogel

Mesenchymal stem cells isolated from different tissues should share associated markers and the capability to differentiate to mesodermal lineages. However, their behavior varies in specific microenvironments. Herein, adhesion and fibrinolytic activity of mesenchymal stem cells from placenta, bone marrow, and Wharton’s jelly were evaluated in fibrin hydrogels prepared with nonpurified blood plasma and compared with two-dimensional cultures. Despite the source, mesenchymal stem cells adhered through focal adhesions positive for vinculin and integrin αV in two dimensions, while focal adhesions could not be detected in fibrin hydrogels. Moreover, some cells could not spread and stay rounded. The proportions of elongated and round phenotypes varied, with placenta mesenchymal stem cells having the lowest percentage of elongated cells (~10%). Mesenchymal stem cells degraded fibrin at distinct rates, and placenta mesenchymal stem cells had the strongest fibrinolytic activity, which was achieved principally through the plasminogen–plasmin axis. These findings might have clinical implications in tissue engineering and wound healing therapy

Influence of the PLGA/gelatin ratio on the physical, chemical and biological properties of electrospun scaffolds for wound dressings

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