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1.
Heliyon ; 10(14): e34395, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39130475

RESUMO

This article aims to measure energy poverty in Colombia in its thirty-two departments and its capital city from 2018 to 2022, using a composite approach. To achieve this, a Multidimensional Energy Poverty Index (MEPI) was designed, according to the methodology proposed by Nussbaumer et al. (2012; 2013) [1,2]. Twenty-eight variables were used, which were distributed across seven dimensions, and recorded by the National Quality of Life Survey (ECV, Spanish acronym), administered by the National Administrative Department of Statistics (DANE) of Colombia. In addition, a nested weighting method was used to assign weights within the index. Subjective weights were given to the dimensions, and an entropy method was used for each of the component variables. The results show that energy poverty has an increasing trend in Colombia throughout the period, especially in the municipal capitals. There are significant differences between urban and rural areas in all territories, and the departments located in the most remote areas of the country have a higher energy poverty. This is consistent with the low population density, as well as with off-grid areas. The results obtained will allow decision makers to conduct a preliminary evaluation of the management and effects of the specific public policy programs and plans that have been implemented in the different territories of the country.

2.
Small ; : e2402419, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004887

RESUMO

This study focuses on designing and evaluating scaffolds with essential properties for bone regeneration, such as biocompatibility, macroporous geometry, mechanical strength, and magnetic responsiveness. The scaffolds are made using 3D printing with acrylic resin and iron oxides synthesized through solution combustion. Utilizing triply periodic minimal surfaces (TPMS) geometry and mask stereolithography (MSLA) printing, the scaffolds achieve precise geometrical features. The mechanical properties are enhanced through resin curing, and magnetite particles from synthesized nanoparticles and alluvial magnetite are added for magnetic properties. The scaffolds show a balance between stiffness, porosity, and magnetic responsiveness, with maximum compression strength between 4.8 and 9.2 MPa and Young's modulus between 58 and 174 MPa. Magnetic properties such as magnetic coercivity, remanence, and saturation are measured, with the best results from scaffolds containing synthetic iron oxides at 1% weight. The viscosity of the mixtures used for printing is between 350 and 380 mPas, and contact angles between 90° and 110° are achieved. Biocompatibility tests indicate the potential for clinical trials, though further research is needed to understand the impact of magnetic properties on cellular interactions and optimize scaffold design for specific applications. This integrated approach offers a promising avenue for the development of advanced materials capable of promoting enhanced bone regeneration.

3.
Nurs Rep ; 14(2): 1517-1527, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38921724

RESUMO

Chronic diseases such as type 2 diabetes mellitus (T2DM), arterial hypertension (HTN), and obesity are significant global health challenges, contributing to millions of premature deaths. In Mexico, these pose major challenges due to limited access to healthcare and inadequate primary care quality. Complementary medicine presents itself as an adjuvant in this context, offering minimally invasive techniques to enhance physical, mental, and spiritual well-being. However, effective treatment adherence is crucial for positive outcomes, influenced by self-efficacy, resulting in persistently low adherence rates-a pressing public health concern. This observational study aimed to explore how perceptions of complementary medicine and treatment adherence predict self-efficacy among individuals with chronic diseases in Mexico. Data were collected from 113 participants with chronic conditions, including T2DM, HTN, and obesity. Participants completed surveys assessing perception of complementary medicine, treatment adherence, and self-efficacy. Statistical analyses, including correlations and regression, were conducted to examine the relationships between variables. The study revealed significant correlations between the perception of complementary medicine, treatment adherence, and self-efficacy. Treatment adherence was positively associated with self-efficacy, while perception of holistic medicine was negatively correlated with self-efficacy. Perception of complementary medicine and adherence to treatment were found to predict 41.9% (p = 0.001) self-efficacy. These findings underscore the potential of complementary therapies in enhancing self-efficacy levels, and highlight the importance of holistic healthcare approaches in managing chronic conditions. Further research is needed to better understand these relationships and their implications for healthcare outcomes in Mexico and beyond.

4.
Vector Borne Zoonotic Dis ; 24(8): 499-509, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38836751

RESUMO

Background: Marsupials and rodents are the most important wild and synanthropic hosts of Trypanosoma cruzi due to the high frequency of infection, maintenance of diverse genetic populations of the parasite, and their close proximity to interact with both transmission cycles, sylvatic and peridomestic. Our aim was to identify the discrete typing units (DTU) of T. cruzi from different wild and synanthropic hosts in two regions of Mexico and to carry out a review of historical data focusing on current knowledge on the diversity and T. cruzi DTUs of host species. Materials and Methods: One hundred fifteen samples were obtained from two areas in Tabasco and Nayarit state. The presence of T. cruzi was evaluated by PCR. Results: The 12.6% (12/95) of samples from Tabasco and 65% (13/20) from Nayarit were found to be positive for parasite DNA. All the sequences analyzed were grouped in T. cruzi DTU I; low nucleotide diversity was observed in Tabasco (π = 0.00566, and Ï´ = 0.00632), while high genetic diversity was observed in Nayarit sequences, up to 8.63 (π) to 11.10 (Ï´) times greater than Tabasco sequences. Genetic flow and migration between Tabasco, and Nayarit were scarce (FST = 0.37329 and Nm = 0.42), and genetic exchange was observed only between nearby areas. The bibliographic review of hosts in Mexico, together with our data, shows a heterogeneous T. cruzi prevalence in Chiroptera and domestic animals. For Atelidae and Canids, prevalence is generally below 25%. However, a high prevalence, greater than 25% and up to 100%, was recorded in Didelphimorphia, and Rodentia. Few studies in regions of Mexico have been described as infected with the parasite; in these, the genetic group with the highest prevalence is the DTU I. Conclusion: Marsupials and rodents are important reservoirs of T. cruzi; DTU I was frequently reported; however, recent genetic and reservoir studies have demonstrated the presence of greater diversity of genetic groups.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/classificação , Animais , México/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Doença de Chagas/transmissão , Animais Selvagens/parasitologia , Mamíferos/parasitologia , Variação Genética , Roedores/parasitologia
5.
J Am Pharm Assoc (2003) ; 64(4): 102056, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38401839

RESUMO

BACKGROUND: Non-medical use of psychoactive medication is a public health problem. Studies in other contexts indicate that individual sociodemographic characteristics are associated with non-medical use, but these associations have not been assessed in the Mexican context. OBJECTIVES: To estimate the prevalence non-medical and medical use of psychoactive medication among Mexican adolescents and adults' medication users and to estimate the associations between sociodemographic characteristics and non-medical use of psychoactive medication, using data from a nationally representative sample. METHODS: Secondary analysis of data collected from the National Survey of Drug, Alcohol, and Tobacco Consumption (ENCODAT) 2016 to 2017. The analytical sample included people aged 12 to 65 years. The sample was stratified into two age categories: adolescents (12-17 years) and adults (18-65 years). Sub-analyses were performed to describe prevalence of use and non-medical use of psychoactive medication at the state-level. Descriptive statistics and multinomial logistic regression models were used to estimate associations between sociodemographic characteristics and medical, non-medical, and non-use of psychoactive medication in adolescents and adults. RESULTS: Among Mexican medication users in 2016, the national prevalence of non-medical use of psychoactive drugs was 19.6%; 22.2% among adolescents and 19.4% among adults. States adjacent to the US-Mexico border reported the highest levels of non-medical use of psychoactive medication. Illicit drug consumption was associated with non-medical use. Sociodemographic characteristics associated with non-medical use varied between adolescents and adults. CONCLUSIONS: There is a high proportion of non-medical use of psychoactive drugs among Mexican medication users, especially among young people. Understanding factors associated with the misuse of psychoactive medications in Mexico can inform policy for prevention and treatment.


Assuntos
Psicotrópicos , Humanos , Adolescente , México , Masculino , Psicotrópicos/uso terapêutico , Feminino , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Criança , Prevalência , Inquéritos e Questionários , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Fatores Sociodemográficos
6.
Front Bioeng Biotechnol ; 12: 1321466, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361789

RESUMO

Context: The development of porous devices using materials modified with various natural agents has become a priority for bone healing processes in the oral and maxillofacial field. There must be a balance between the proliferation of eukaryotic and the inhibition of prokaryotic cells to achieve proper bone health. Infections might inhibit the formation of new alveolar bone during bone graft augmentation. Objective: This study aimed to evaluate the in vitro osteogenic behavior of human bone marrow stem cells and assess the antimicrobial response to 3D-printed porous scaffolds using propolis-modified wollastonite. Methodology: A fractional factorial design of experiments was used to obtain a 3D printing paste for developing scaffolds with a triply periodic minimal surface (TPMS) gyroid geometry based on wollastonite and modified with an ethanolic propolis extract. The antioxidant activity of the extracts was characterized using free radical scavenging methods (DPPH and ABTS). Cell proliferation and osteogenic potential using Human Bone Marrow Stem Cells (bmMSCs) were assessed at different culture time points up to 28 days. MIC and inhibition zones were studied from single strain cultures, and biofilm formation was evaluated on the scaffolds under co-culture conditions. The mechanical strength of the scaffolds was evaluated. Results: Through statistical design of experiments, a paste suitable for printing scaffolds with the desired geometry was obtained. Propolis extracts modifying the TPMS gyroid scaffolds showed favorable cell proliferation and metabolic activity with osteogenic potential after 21 days. Additionally, propolis exhibited antioxidant activity, which may be related to the antimicrobial effectiveness of the scaffolds against S. aureus and S. epidermidis cultures. The mechanical properties of the scaffolds were not affected by propolis impregnation. Conclusion: These results demonstrate that propolis-impregnated porous wollastonite scaffolds might have the potential to stimulate bone repair in maxillofacial tissue engineering applications.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38324874

RESUMO

Currently, there are some concerns about the situation and, in particular, about the future of the COVID-19 pandemic and the new emerging variants of SARS-CoV-2. Rodents are an example of synanthropic animals in urban environments that harbor important zoonoses. Although the molecular identification of SARS-CoV-2 in Rattus norvegicus from New York City had been reported, in other studies, urban wild rodents infected with this virus have not been found. This study aimed to molecularly identify the presence of SARS-CoV-2 in urban wild rodents from Mexico City, trapped along a water channel of a public park as part of a pest control program, at the beginning of the COVID-19 pandemic, during the fall and winter of 2020. Up to 33 Mus musculus and 52 R. norvegicus were captured and euthanized, large intestine samples with feces from the animals were obtained. RNAs were obtained and subjected to qRT-PCR for SARS-CoV-2 identification and threshold cycle (Ct) values were obtained. Four mice (12.1%) and three rats (5.8%) were positive, three rodents exhibited Ct<30. Our results on the frequency of SARS-CoV-2 in urban rats are in line with other previous reports. Thus, similar to other authors, we suggest that surveillance for the detection of SARS-CoV-2 in urban wild rodents, as sentinel animals, should be maintained.


Assuntos
COVID-19 , Roedores , Ratos , Camundongos , Animais , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , México/epidemiologia , Pandemias
8.
Heliyon ; 10(1): e23955, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38205336

RESUMO

Biocompatible ceramic scaffolds offer a promising approach to address the challenges in bone reconstruction. Wollastonite, well-known for its exceptional biocompatibility, has attracted significant attention in orthopedics and craniofacial fields. However, the antimicrobial properties of wollastonite have contradictory findings, necessitating further research to enhance its antibacterial characteristics. This study aimed to explore a new approach to improve in vitro biological response in terms of antimicrobial activity and cell proliferation by taking advantage of additive manufacturing for the development of scaffolds with complex geometries by 3D printing using propolis-modified wollastonite. The scaffolds were designed with a TPMS (Triply Periodic Minimal Surface) gyroid geometric shape and 3D printed prior to impregnation with propolis extract. The paste formulation was characterized by rheometric measurements, and the presence of propolis was confirmed by FTIR spectroscopy. The scaffolds were comprehensively assessed for their mechanical strength. The biological characterization involved evaluating the antimicrobial effects against Staphylococcus aureus and Staphylococcus epidermidis, employing Minimum Inhibitory Concentration (MIC), Zone of Inhibition (ZOI), and biofilm formation assays. Additionally, SaOs-2 cultures were used to study cell proliferation (Alamar blue assay), and potential osteogenic was tested (von Kossa, Alizarin Red, and ALP stainings) at different time points. Propolis impregnation did not compromise the mechanical properties of the scaffolds, which exhibited values comparable to human trabecular bone. Propolis incorporation conferred antibacterial activity against both Staphylococcus aureus and Staphylococcus epidermidis. The implementation of TPMS gyroid geometry in the scaffold design demonstrated favorable cell proliferation with increased metabolic activity and osteogenic potential after 21 days of cell cultures.

9.
Vet Res Commun ; 48(2): 1211-1217, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37938422

RESUMO

Trichinella is a nematode that are spread by the consumption of parasitized meat. Carnivora, a mammalian order, serve as key hosts for this parasite. However, evidence of Trichinella in wildlife from the Neotropics is extremely scarce, with reports documenting its presence only for five carnivore species: two Felidae, one Otariidae and two Mustelidae. Other widely distributed species that are consumed as bushmeat, such as Procyonidae, have not been studied in this context. A long-term study was performed for antibodies against Trichinella in coatis (Nasua narica) and common raccoons (Procyon lotor) in southeastern Mexico. Between the summer of 2009 to the winter 2013, a total of 291 coati samples and 125 raccoon samples were collected from a tropical green area located within an urban zone. An Enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies against the excretory and secretory products of Trichinella spiralis muscle larva. ELISA-positive samples were further confirmed by Western Blot analysis. Results showed no evidence of antibodies during the first two years of study. However, in 2011, a sudden appearance of anti-Trichinella occurred. The seroprevalence reached its highest peak of 43% for coatis during winter 2013 and 53% for raccoons in summer 2013. This is the first study that provides evidence of Trichinella circulation within a neotropical procyonid community.


Assuntos
Mustelidae , Procyonidae , Trichinella , Animais , Guaxinins/parasitologia , Procyonidae/parasitologia , México , Estudos Soroepidemiológicos
10.
SSM Popul Health ; 25: 101571, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38148998

RESUMO

In Colombia, more than 4 per cent of the population lives with disability and high levels of income and multidimensional poverty have been recognised within this group. However, there is no information on how the levels of poverty have changed over time or whether households with members with disabilities are more likely to be chronically poorer than households without disabilities in the country. In addition, no evidence exists on the potential effect of the Covid-19 pandemic on the socioeconomic characteristics of persons with disability. This study aims to contribute to the literature on this topic by analysing a nationally representative survey (Quality of Life Survey) from 2018 to 2022 and studying the changes in the levels of income and multidimensional poverty of persons with disabilities and their household, and identifying whether any changes associated with the Covid-19 pandemic.

11.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1535308

RESUMO

ABSTRACT Currently, there are some concerns about the situation and, in particular, about the future of the COVID-19 pandemic and the new emerging variants of SARS-CoV-2. Rodents are an example of synanthropic animals in urban environments that harbor important zoonoses. Although the molecular identification of SARS-CoV-2 in Rattus norvegicus from New York City had been reported, in other studies, urban wild rodents infected with this virus have not been found. This study aimed to molecularly identify the presence of SARS-CoV-2 in urban wild rodents from Mexico City, trapped along a water channel of a public park as part of a pest control program, at the beginning of the COVID-19 pandemic, during the fall and winter of 2020. Up to 33 Mus musculus and 52 R. norvegicus were captured and euthanized, large intestine samples with feces from the animals were obtained. RNAs were obtained and subjected to qRT-PCR for SARS-CoV-2 identification and threshold cycle (Ct) values were obtained. Four mice (12.1%) and three rats (5.8%) were positive, three rodents exhibited Ct<30. Our results on the frequency of SARS-CoV-2 in urban rats are in line with other previous reports. Thus, similar to other authors, we suggest that surveillance for the detection of SARS-CoV-2 in urban wild rodents, as sentinel animals, should be maintained.

13.
Salud Publica Mex ; 65(4, jul-ago): 344-352, 2023 Jul 15.
Artigo em Espanhol | MEDLINE | ID: mdl-38060901

RESUMO

OBJETIVO: Analizar la estructura factorial, la validez convergente y divergente de la Escala Columbia de Severidad Suicida (CSSRS) y el Cuestionario de Eventos de Vida Estresantes (EVE) y medir la asociación entre EVE y conducta suicida (CS) en mujeres mexicanas durante la pandemia por Covid-19. Material y métodos. Se usaron datos de 2 398 mujeres que participaron en un estudio multicéntrico, realizado en México entre mayo y octubre de 2021. La información se recolectó mediante un cuestionario en línea que incluyó la CSSRS y el EVE. Se hizo un análisis factorial confirmatorio para valorar el ajuste de los modelos. RESULTADOS: El modelo final mostró asociación entre los EVE y la CS, y tuvo a la violencia como variable central. Dicho modelo presentó un ajuste adecuado (CFI = 0.950, IFI = 0.950, MFI = 0.975, RMSEA = 0.031, CI RMSEA = 0.026-0.036). CONCLUSIONES: La pandemia por Covid-19 evidenció la necesidad de crear e implementar estrategias que promuevan el cuidado de la salud mental, reduzcan la exposición a la violencia y faciliten los procesos de duelo para prevenir la CS en mujeres mexicanas.

14.
Salud Publica Mex ; 65(5, sept-oct): 475-484, 2023 Sep 15.
Artigo em Espanhol | MEDLINE | ID: mdl-38060918

RESUMO

OBJECTIVE: To analyze, from the perspective of intersectionality, the association of social inequality dimensions (occupation, poverty, and educational level) and socio-demographic and health characteristics with the proportion of depressive symptoms among males and females aged 50 years and older who participated in the 2001 and 2012 waves of the Mexican Health and Aging Study (MHAS). MATERIALS AND METHODS: Descriptive analysis and logistic regression models stratified by sex were performed, including interaction terms between poverty, educational level, and employment conditions on the presence of depressive symptoms. RESULTS: The proportion of females with depressive symptoms was significantly higher than that of males in both waves. A high proportion of older females in poverty, with five years or less of education and manual occupational activities, reported depressive symptoms in the MHAS-2001. The interactions evaluated between occupation, poverty, and educational level were not statistically significant under adjusted models; however, disability and comorbidities were associated with depressive symptoms in both sexes. CONCLUSION: A higher proportion of females have depressive symptoms under conditions of inequality; however, the effect of the intersection between employment and socio-demographic characteristics on depressive symptoms was not observed under adjusted models.

15.
Rev. costarric. cardiol ; 25(2): 25-36, jul.-dic. 2023. tab, graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559764

RESUMO

RESUMEN El presente trabajo es el resultado de una iniciativa para analizar, resumir y mostrar la evidencia científica más reciente sobre el tema de la hipertensión y la implementación de las mejores terapéuticas disponibles. Este documento fue creado con la colaboración conjunta de médicos especialistas para dar una perspectiva local a la gestión basada en la mejor evi- dencia científica y en el contexto de la región de Centroamérica y el Caribe. Este artículo cuenta con el respaldo científico y académico de la Sociedad Centroamericana y del Caribe de Cardiología y es el primero de su tipo en abordar el problema y tema de la hipertensión. Se desarrolló a partir de una revisión detallada de la evidencia científica utilizando los principales buscadores médicos, seleccionando los estudios pivotales y poblacionales con mayor nivel de evidencia disponible. La in- tención es brindar información sencilla, con recomendaciones fáciles de implementar en el manejo diario de los pacientes con hipertensión arterial. Este documento contó con el apoyo logístico del Laboratorio Servier, tanto con los autores como en su edición; sin embargo, la información clínica presentada no estuvo condicionada por el laboratorio. Este material es responsabilidad de los autores.


ABSTRACT Antihypertensive therapy recommendations: the importance of combinations Endorsed by the Central American and Caribbean Society of Cardiology The present work is the result of an initiative to analyze, summarize, and show the latest scientific evidence on the subject of hypertension and the implementation of the best available therapeutics. This document was created with the joint collaboration of medical specialists to give a local perspective to the management based on the best scientific evidence and in the context of the Central American and Caribbean region. This paper has the scientific and academic support of the Central American and Caribbean Society of Cardiology and is the first of its kind to address the problem and topic of hypertension. It was developed from a detailed review of the scientific evidence using the main medical search engines, selecting the pivotal and population-based studies with the highest level of evidence available. The intention is to provide simple information, with easy-to-implement recommendations to implement in the daily management of patients with arterial hypertension. This document had the logistic support of Servier Laboratory, both with the authors as well as its editing; however, the clinical information presented was not conditioned by the laboratory. This material is the responsibility of the authors.


Assuntos
Humanos , Terapia Combinada/métodos , Hipertensão/terapia , Cardiologia
16.
Front Public Health ; 11: 1157581, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37732099

RESUMO

The aim of this study was to evaluate the validity and psychometric properties in a Mexican sample of a Spanish-language online version of the Columbia-Suicide Severity Rating Scale (C-SSRS). Data were collected between May and October 2021 from 3,645 participants aged 18 years and over, who agreed to complete the questionnaire. Reliability analysis, confirmatory factor analysis (CFA), and psychometric properties were calculated using a two-parameter model. The results showed a reasonable level of reliability with a Cronbach's alpha of 0.814, and evidence of unidimensionality, and construct validity for suicide risk at three risk levels: low, medium, and high. Analysis of the items suggests that they are consistent with the proposed theoretical model. Our results also demonstrate that the parameters are stable and able to efficiently discriminate individuals at high risk of suicide. We propose the use of this version of the C-SSRS in the Spanish-speaking population, since it is a multifactorial assessment of suicide risk and the inclusion of other clinical and risk factor assessments for a more comprehensive evaluation.


Assuntos
Suicídio , Humanos , Adolescente , Adulto , Psicometria , Reprodutibilidade dos Testes , Análise Fatorial , Idioma
17.
Rural Remote Health ; 23(3): 7695, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37666503

RESUMO

INTRODUCTION: This article analyzes risk discourses around dengue, zika and chikungunya constructed by lay people, community leaders and disease control experts from the fields of medical anthropology, medical sociology, and public health. METHODS: A qualitative ethnographic study was conducted in a municipality in Colombia (December 2016 and January 2018) with semistructured and open-ended interviews, informal dialogues, and fieldwork journal observations. RESULTS: This study found a mismatch in risk discourse about vector-borne diseases among health officials, lay people, and community leaders. These discourses are linked to the sociocultural contexts in which people live, and offer particular ways of giving meaning and acting in the face of disease prevention. CONCLUSION: The findings show a multisituated risk that refers to the inside and outside of homes; and the prevention practices mentioned by different actors, in which a continuity of tensions between lay people, leaders and government officials can be observed.


Assuntos
Aedes , Doenças Transmitidas por Vetores , Infecção por Zika virus , Zika virus , Animais , Humanos , Colômbia , Mosquitos Vetores , Saúde Pública , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/prevenção & controle
18.
Front Microbiol ; 14: 1195776, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426024

RESUMO

Human activities significantly influence the health of aquatic ecosystems because many noxious chemical wastes are discharged into freshwater bodies. Intensive agriculture contributes to the deterioration by providing indirectly fertilizers, pesticides, and other agrochemicals that affect the aquatic biota. Glyphosate is one of the most used herbicides worldwide, and microalgae are particularly sensitive to its formulation, inducing displacement of some green microalgae from the phytoplankton that leads to alterations in the floristic composition, which fosters the abundance of cyanobacteria, some of which can be toxigenic. The combination of chemical stressors such as glyphosate and biological ones, like cyanotoxins and other secondary metabolites of cyanobacteria, could induce a combined effect potentially more noxious to microalgae, affecting not only their growth but also their physiology and morphology. In this study, we evaluated the combined effect of glyphosate (Faena®) and a toxigenic cyanobacterium on the morphology and ultrastructure of microalgae in an experimental phytoplankton community. For this purpose, Microcystis aeruginosa (a cosmopolitan cyanobacterium that forms harmful blooms) and the microalgae Ankistrodesmus falcatus, Chlorella vulgaris, Pseudokirchneriella subcapitata, and Scenedesmus incrassatulus were cultivated, individually and jointly, exposing them to sub-inhibitory concentrations of glyphosate (IC10, IC20, and IC40). Effects were evaluated through scanning electron (SEM) and transmission electron (TEM) microscopy. Exposure to Faena® produced alterations in the external morphology and ultrastructure of microalgae both individually and in combined cultures. SEM evidenced the loss of the typical shape and integrity of the cell wall and an increase in the biovolume. TEM revealed reduction and disorganization of the chloroplast, variation in starch and polyphosphate granules, formation of vesicles and vacuoles, cytoplasm degradation, and cell wall continuity loss. The presence of M. aeruginosa was, for microalgae, an additional stress factor adding to the chemical stress produced by Faena®, increasing the damage in their morphology and ultrastructure. These results alert to the effects that can be caused by glyphosate and the presence of toxigenic bacteria on the algal phytoplankton in contaminated and anthropic and eutrophic freshwater ecosystems.

19.
Exp Appl Acarol ; 91(1): 111-121, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37468804

RESUMO

The microbiome represents a complex network among the various members of the community of microorganisms that are associated with a host. The composition of the bacterial community is essential to supplement multiple metabolic pathways that the host lacks, particularly in organisms with blood-sucking habits such as ticks. On the other hand, some endosymbionts showed some competence with potentially pathogenic microorganisms. Francisella-like endosymbionts (FLEs) encompass a group of gamma-proteobacterias that are closely related to Francisella tularensis, but are usually apathogenic, which brings nutrients like vitamin B and other cofactors to the tick. It has been postulated that the main route of transmission of FLE is vertical; however, evidence has accumulated regarding the possible mechanism of horizontal transmission. Despite growing interest in knowledge of endosymbionts in the Neotropical region, the efforts related to the establishment of their inventory for tick communities are concentrated in South and Central America, with an important gap in knowledge in Mesoamerican countries such as Mexico. For this reason, the aim of this work was to evaluate the presence and diversity of endosymbionts in the highly host-specialized tick Amblyomma nodosum collected from the anteater Tamandua mexicana in Mexico. We analysed 36 A. nodosum for the presence of DNA of endosymbiont (Coxiella and Francisella) and pathogenic (Anaplasma, Borrelia, Ehrlichia and Rickettsia) bacteria. The presence of a member of the genus Francisella and Candidatus Anaplasma brasiliensis was demonstrated. Our findings provide information on the composition of A. nodosum's microbiome, increasing the inventory of bacterial species associated with this hard tick on the American continent.


Assuntos
Amblyomma , Gammaproteobacteria , Amblyomma/microbiologia , Animais , Vermilingua/parasitologia , México , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Masculino , Feminino , Filogenia
20.
Zool Res ; 44(4): 761-775, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464933

RESUMO

Cave-adapted animals provide a unique opportunity to study the evolutionary mechanisms underlying phenotypic, metabolic, behavioral, and genetic evolution in response to cave environments. The Mexican tetra ( Astyanax mexicanus) is considered a unique model system as it shows both surface and cave-dwelling morphs. To date, at least 33 different cave populations have been identified, with phylogenetic studies suggesting an origin from at least two independent surface lineages, thereby providing a unique opportunity to study parallel evolution. In the present study, we carried out the most exhaustive phylogeographic study of A. mexicanus to date, including cave and surface localities, using two mitochondrial markers (cytochrome b (cyt b) and cytochrome c oxidase subunit I ( COI)) and nuclear rhodopsin visual pigment ( rho). Additionally, we inferred the molecular evolution of rho within the two contrasting environments (cave and surface) and across three geographic regions (Sierra de El Abra, Sierra de Guatemala, and Micos). In total, 267 individuals were sequenced for the two mitochondrial fragments and 268 individuals were sequenced for the rho visual pigment from 22 cave and 46 surface populations. Phylogeographic results based on the mitochondrial data supported the two-lineage hypothesis, except for the Pachón and Chica caves, whose introgression has been largely documented. The Sierra de El Abra region depicted the largest genetic diversity, followed by the Sierra de Guatemala region. Regarding the phylogeographic patterns of rho, we recovered exclusive haplogroups for the Sierra de El Abra (Haplogroup I) and Sierra de Guatemala regions (Haplogroup IV). Moreover, a 544 bp deletion in the rho gene was observed in the Escondido cave population from Sierra de Guatemala, reducing the protein from seven to three intramembrane domains. This change may produce a loss-of-function (LOF) but requires further investigation. Regarding nonsynonymous ( dN) and synonymous ( dS) substitution rates (omega values ω), our results revealed the prevailing influence of purifying selection upon the rho pigment for both cave and surface populations (ω<1), but relaxation at the El Abra region. Notably, in contrast to the other two regions, we observed an increase in the number of dN mutations for Sierra de El Abra. However, given that a LOF was exclusively identified in the Sierra de Guatemala region, we cannot dismiss the possibility of a pleiotropic effect on the Rho protein.


Assuntos
Characidae , Rodopsina , Animais , Filogeografia , Filogenia , Rodopsina/genética , Characidae/genética , Evolução Molecular
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