Evaluation of the genotoxic effect of heavy metals in pigeons from urban and rural habitat in Monterrey, Mexico, using the chromatin dispersion assay.

PURPOSE: Evaluate genotoxic effect of heavy metals on Pigeon Erythrocytes (PE) from urban and rural habitat (outside of the city) in Monterrey, Mexico, using the chromatin dispersion assay. MATERIALS AND METHODS: We quantified metals concentrations (Cd, Hg, Cu and Pb) in tail feathers of 22 pigeons from an urban and a rural site in northeastern Mexico. DNA damage in peripheral blood erythrocytes was measured by chromatin dispersion assay in 13 pigeon living in urban habitat and in nine living in rural habitat as the control. MicroNucleus (MN) test was used to confirm levels of DNA damage. RESULTS: Birds in urban habitat had highest concentrations in feathers for all the metallic elements analysed with respect to birds in rural habitat. Concentrations of Cu and Hg showed a significant increase (p < 0.05). Our results showed a significant increase of DNA damage in urban-habitat pigeons compared with that of pigeons in rural area. These results were confirmed by a MN test. CONCLUSIONS: Our preliminary findings demonstrate that PE examination via chromatin dispersion assay is a reliable, precise and inexpensive morphological bioassay for evaluating environmental genotoxicity associated with heavy metals. Further studies for evaluating the individual participation of contaminants in DNA damage are needed.

Classification and ordination of main plant communities along an altitudinal gradient in the arid and temperate climates of northeastern Mexico.

Quantitative data on the ecology of the main plant communities along an altitudinal gradient in northeastern Mexico were obtained with the aim of identifying the most important environmental variables that affect plant distribution and composition. The main threats to these communities were also investigated. Importance value index (IVi) of the 39 most important species and 16 environmental variables were recorded at 35 altitudinal gradients each spaced at intervals of at least 100-m altitude. Classification and ordination of vegetation showed six well-differentiated but overlapping plant communities: alpine meadow, cold conifer forest, mesic mixed forest, xeric scrub, Tamaulipan piedmont scrub, and halophytic grassland. Altitude, minimum and average temperatures, and organic matter content are the main variables affecting the plant distribution in northeastern Mexico. Urban growth, mechanized agriculture, and changes in land use are the main threats in the short and medium term to plant communities in this area. Climate change also seems to be having an impact at present or in the near future as shown by the presence of exotic shrubs from warmer areas in mesic and temperate areas inhabited by oak and oak-pine forest.

The Fabaceae in Northeastern Mexico (Subfamily Caesalpinioideae, Mimosoideae Clade, Tribes Mimoseae, Acacieae, and Ingeae).

A synoptic compendium of the legumes of the Mimosoideae clade in northeastern Mexico is presented for the first time, including changes in their botanical nomenclature and retypification of genera. Furthermore, based on new information recently published, the taxonomic limits of several new genera segregated from Acacia (Acaciella, Mariosousa, Senegalia, and Vachellia) and Prosopis (Neltuma and Strombocarpa) are clarified and included. Based on field work, collection of botanical samples over the past 30 years, and reviewing botanical materials in national and international herbaria, we have completed the diversity of legumes of the Mimosoideae clade of northeastern Mexico. Three tribes (Acacieae, Ingeae, and Mimosaeae), 22 genera, 92 species, and 19 infraspecific categories were recorded. Only the genus Painteria is endemic to Mexico. Eighty-eight species are native to Mexico, and four are exotic: Acacia salicina, Neptunia prostrata, Neltuma chilensis and Albizia lebbeck. Twenty-eight species are endemic to Mexico, nine species are endemic to northeastern Mexico, and four species are endemic to only one state in Mexico. The 22 registered genera represent 44% and 65% of the generic flora of the Mimosoideae clade for Mexico and the planet, respectively, while the 92 species registered represent 3% and 18% of the species of the clade Mimosoideae for the planet and Mexico, respectively. According to the new nomenclature of legumes, the number of genera in the Mimosoideae clade in northern Mexico has increased from 19 to 24.

The association of air pollution in respiratory allergy: Its impact in an industrial city.

Background: Asthma and allergic diseases have increased in recent decades and are more common in industrialized countries. Industrial areas with a considerably high number of inhabitants and vehicles can favor the presence of serious air pollution and therefore the appearance and exacerbation of respiratory allergy symptoms. The objective of this study was to determine the relationship between exposure to environmental pollutants with exacerbation of respiratory allergy. Methods: A total of 240 subjects above 6 years old who lived in the metropolitan area of Monterrey, Nuevo León, Mexico, with diagnosis of allergic rhinitis and/or asthma, were included. The subject's address was registered in the database and the rhinitis control assessment test (RCAT) and the asthma control test (ACT) were applied. Environmental data were obtained from the Environmental Monitoring System (SIMA) of Nuevo León. Geolocation of industries and avenues in proximity of subject's addresses and SIMA stations were obtained through geographic information systems using ArcGis software. Results: The relation between pollutants and subjects' RCAT, ACT, and spirometry results in the 14 stations was established. PM10 and forced vital capacity (FVC) had an r = 0.074 with p = 0.005, PM10 and absolute FEV1/FVC ratio presented an r = -0.102 with a p = 0.000; The distance found to be associated with a worsening of respiratory symptoms was living 165 m from a main road or 241 m from an industrial establishment. Conclusions: Exposure to pollutants present in the environment are factors associated with increased symptoms in subjects with respiratory allergies.

The Fabaceae in Northeastern Mexico (Subfamilies Caesalpinioideae (Excluding Tribe Mimoseae), Cercidoideae, and Detarioideae).

As part of the Fabaceae project of northeastern Mexico and based on field work, collection of botanical samples over the past 37 years, and reviewing botanical materials in national and international herbaria, the diversity of legumes of the subfamilies Caesalpinioideae (excluding tribe Mimoseae), Cercidoideae, and Detarioideae in northeastern Mexico has been recorded. New nomenclatural changes in tribes and genera of the subfamily Caesalpinioideae found in the new scientific bibliography are included. The subfamily Caesalpinioideae (excluding the tribe Mimoseae) includes five tribes: tribe Caesalpinieae, with eight genera (Caesalpinia, Coulteria, Denisophytum, Erythrostemon, Guilandina, Hoffmannseggia, Haematoxylum, and Pomaria) and 21 species; tribe Cassieae with three genera (Cassia, Chamaecrita, and Senna) and 28 species; tribe Ceratonieae with one genus (Ceratonia) and 1 species; tribe Gleditsieae with one genus (Gleditsia) and 1 species. The subfamily Cercidoideae includes two genera (Bauhinia and Cercis) and eight species, and the subfamily Detarioideae includes only one genus and one species (Tamarindus indicus). The total flora of these three subfamilies comprises 18 genera and 63 species, including 56 native species and 7 exotic ones: Bauhinia variegata, Cassia fistula, Ceratonia siliqua, Delonix regia, Erythrostemon gilliesii, Senna alata, and Tamarindus indicus. Endemism includes a total of 22 species and nine infraspecific categories.

Impacto del COVID-19 en la esperanza de vida en los municipios de los estados del noreste de México / COVID-19 impact on life expectancy among municipalities of Northeastern states of Mexico

RESUMEN La mortalidad causada por COVID-19 en México se ha situado entre las más altas del mundo, por lo que es de interés epidemiológico estudiar su impacto respecto a la esperanza de vida (EV). El objetivo del presente trabajo fue analizar el impacto de la pandemia por COVID-19 en la esperanza de vida, comparando datos de 2019 y 2020, y evaluando su efecto por densidad poblacional de los municipios de los estados del noreste de México. La información sobre mortalidad para 2019 y 2020 se obtuvo de la Secretaría de Salud, y la demográfica del Consejo Nacional de Población. Se construyeron tablas de vida mediante el método actuarial estándar; se calcularon percentiles ≤ 25 y ≥ 75 de la diferencia en la EV; se evaluó la relación entre el tamaño de la población de los municipios y la magnitud de la diferencia en la pérdida de años en la EV. La pandemia por COVID-19 impactó en la EV en los estados del noreste de México, con gran heterogeneidad al interior en cada uno de ellos. La pérdida en años en promedio fue, para Coahuila de 5.4, Nuevo León 4.1 y Tamaulipas 4.9. Los municipios del percentil ≥ 75 mostraron una pérdida promedio de 9.2 años y los del percentil ≤ 25 de -0.35 años. La diferencia en la pérdida en años de EV, entre 2019 y 2020, se vio influenciada por el tamaño de la población, tendiendo a ser mayor en aquellos con mayor densidad demográfica, sin ser el único factor determinante.

ABSTRACT COVID-19 mortality in Mexico is among the highest in the world. Therefore, it is of epidemiologic interest to study its impact on life expectancy. The aim of the present paper was to analyze the impact of the COVID-19 pandemic on life expectancy through a comparison of data from 2019 and 2020. Specifically, the effect of population density in municipalities of Northeastern Mexican states. Information regarding 2019 and 2020 mortality rates for was obtained from the Ministry of Health, and demographics from the National Population Council. Life tables were constructed using the standard actuarial method. Percentiles ≤ 25 and ≥ 75 of the difference in life expectancy in the period were calculated. The relationship between the size of the population of the municipalities and the magnitude of the difference in life expectancy loss of years was evaluated. COVID-19 pandemic impacted on life expectancy with great heterogeneity in each of the northeastern states of Mexico. The loss in years in average life expectancy was 5.4 for Coahuila, 4.1 for Nuevo Leon and 4.9 for Tamaulipas. Municipalities above the ≥ 75th percentile showed an average loss of 9.2 years. Those in the lower than ≤ 25th percentile showed a decrease, of -0.35 years. The difference in the loss of life expectancy during 2019 and 2020 was influenced by population size, tending to be greater in those municipalities with higher population density, but was not the only determining factor.