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1.
Environ Monit Assess ; 196(8): 773, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39090345

RESUMO

Rodents are considered good models for investigating genotoxic damage and mutagenic alterations caused by xenobiotic agents, due to their occupation of a wide variety of habitats. However, relatively few in situ studies have focused on DNA damage in wild rodents associated with environmental exposure. In this review, we investigate trends in the application of the micronucleus test and comet assay in in situ studies of wild rodents. A total of 33 papers were identified, distributed across 14 different countries. Brazil and Spain had the most published studies (six each), followed by Bulgaria (n = 5), Mexico (n = 4) and Italy (n = 3). Only 24 of the 2,652 recognized rodent species have been the subject of in situ studies, which have most frequently focus on species of the genus Mus. The protocols used for the micronucleus test and comet assay varied widely, although blood and bone marrow were the primary types of tissue used. Given the paucity of studies on wild rodents, we recommend further research, particularly focusing on the use of this group as bioindicators of environmental quality and the standardization of protocols.


Assuntos
Ensaio Cometa , Dano ao DNA , Monitoramento Ambiental , Testes para Micronúcleos , Roedores , Ensaio Cometa/métodos , Testes para Micronúcleos/métodos , Animais , Monitoramento Ambiental/métodos , Animais Selvagens , Poluentes Ambientais/toxicidade
2.
Environ Res ; 258: 119424, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38879109

RESUMO

Birds are good bioindicators of disturbance in the environment. They are present in different habitats and trophic levels. In addition, rapid urbanization has led birds to use cities as shelter and for seeking food resources. Sewage treatment plants (STPs) are suitable locations for free-living birds within cities. However, few studies address the impacts of emerging pollutants from sewage treatment plants on wild birds. In this sense, the aim of this study was to analyze the genotoxic, mutagenic, and immunological impacts from metal and pollutant exposure on free-living birds collected at a STP. For comparison, birds were collected in a preserved environment, the Silvania National Forest (FLONA). To achieve this, we used non-destructive biomarkers sensitive to environmental changes. Birds were collected in both environments using mist nets. After collection, birds were weighed, measured, species-identified, and released. Blood was collected for comet assay, micronucleus test, and leukocyte profile, while feathers were collected for metal concentration analysis. Water physicochemical parameters were measured at both sites, and water samples were collected for metal analysis. Our results demonstrated that birds collected at the STP exhibit a higher frequency of genotoxic damage and erythrocyte abnormalities, and increased immune response compared to FLONA birds. Traces of potentially toxic metals, such as Hg and As, were found in the birds feathers from both environments, raising concerns about metal contamination in both environments. Trophic guilds appear to respond similarly to exposure. The parameters and metals found in the water reflect environmental characteristics and may be influencing pollutant availability. Finally, despite the advancement of our findings, studies linking these damages to detrimental effects on behavior and reproduction are encouraged.


Assuntos
Biomarcadores , Aves , Urbanização , Animais , Biomarcadores/sangue , Monitoramento Ambiental/métodos , Testes para Micronúcleos , Ensaio Cometa , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Esgotos , Brasil , Metais/análise , Metais/toxicidade , Dano ao DNA , Plumas/química , Ecotoxicologia
3.
Int J Mol Sci ; 25(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892064

RESUMO

Hypertrophic cardiomyopathy (HCM) is a heart condition characterized by cellular and metabolic dysfunction, with mitochondrial dysfunction playing a crucial role. Although the direct relationship between genetic mutations and mitochondrial dysfunction remains unclear, targeting mitochondrial dysfunction presents promising opportunities for treatment, as there are currently no effective treatments available for HCM. This review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews guidelines. Searches were conducted in databases such as PubMed, Embase, and Scopus up to September 2023 using "MESH terms". Bibliographic references from pertinent articles were also included. Hypertrophic cardiomyopathy (HCM) is influenced by ionic homeostasis, cardiac tissue remodeling, metabolic balance, genetic mutations, reactive oxygen species regulation, and mitochondrial dysfunction. The latter is a common factor regardless of the cause and is linked to intracellular calcium handling, energetic and oxidative stress, and HCM-induced hypertrophy. Hypertrophic cardiomyopathy treatments focus on symptom management and complication prevention. Targeted therapeutic approaches, such as improving mitochondrial bioenergetics, are being explored. This includes coenzyme Q and elamipretide therapies and metabolic strategies like therapeutic ketosis. Understanding the biomolecular, genetic, and mitochondrial mechanisms underlying HCM is crucial for developing new therapeutic modalities.


Assuntos
Cardiomiopatia Hipertrófica , Mutação , Oxirredução , Transdução de Sinais , Humanos , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/metabolismo , Animais , Mitocôndrias/metabolismo , Mitocôndrias/genética , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
4.
Entropy (Basel) ; 26(6)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38920535

RESUMO

In this paper, we present a systematic approach to building useful time-dependent effective Hamiltonians in molecular quantum electrodynamics. The method is based on considering part of the system as an open quantum system and choosing a convenient unitary transformation based on the evolution operator. We illustrate our formalism by obtaining four Hamiltonians, each suitable to a different class of applications. We show that we may treat several effects of molecular quantum electrodynamics with a direct first-order perturbation theory. In addition, our effective Hamiltonians shed light on interesting physical aspects that are not explicit when employing more standard approaches. As applications, we discuss three examples: two-photon spontaneous emission, resonance energy transfer, and dispersion interactions.

5.
Genet Mol Biol ; 47(1): e20230172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578013

RESUMO

We announce the mitochondrial genomes of seven species of the genus Sporophila (S. bouvreuil, S. iberaensis, S. melanogaster, S. minuta, S. nigrorufa, S. pileata, and S. ruficollis) which were validated by comparative genomic and phylogenetic analysis with related species. The mitochondrial genomes of seven passerines of the genus Sporophila were assembled (three complete and four nearly complete genomes) and were validated by reconstructing phylogenetic relations within Thraupidae. The complete mitogenomes ranged from 16,781 bp in S. ruficollis to 16,791 bp in S. minuta. We identified a conserved genome composition within all mitogenomes with 13 protein-coding genes, 22 tRNAs and two rRNAs. We observed a bias in the nucleotide composition and six mutational hotspots in Sporophila mitogenomes. Our mitogenome-based phylogenetic tree has S. minuta, S. maximiliani and S. nigricollis as sister species of the remaining species in the genus. We present new mitogenome sequences for seven Sporophila species, providing new genomic resources that may be useful for research on the evolution, comparative genetics, and conservation of this threatened group.

6.
Entropy (Basel) ; 26(3)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38539762

RESUMO

A mirror subjected to a fast mechanical oscillation emits photons out of the quantum vacuum-a phenomenon known as the dynamical Casimir effect (DCE). The mirror is usually treated as an infinite metallic surface. Here, we show that, in realistic experimental conditions (mirror size and oscillation frequency), this assumption is inadequate and drastically overestimates the DCE radiation. Taking the opposite limit, we use instead the dipolar approximation to obtain a simpler and more realistic treatment of DCE for macroscopic bodies. Our approach is inspired by a microscopic theory of DCE, which is extended to the macroscopic realm by a suitable effective Hamiltonian description of moving anisotropic scatterers. We illustrate the benefits of our approach by considering the DCE from macroscopic bodies of different geometries.

7.
Braz J Med Biol Res ; 57: e13105, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38265343

RESUMO

One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.


Assuntos
Confiabilidade dos Dados , Células-Tronco Mesenquimais , Pirenos , Humanos , Diferenciação Celular , Proliferação de Células
8.
Interface (Botucatu, Online) ; 28: e230001, 2024. graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1558190

RESUMO

Com o avançar da tecnologia, passou a fazer parte da graduação médica atual o aprendizado em teleconsultas. Esta pesquisa apresenta as representações de um grupo de alunos de um curso de Medicina localizado na capital do estado de São Paulo sobre suas experiências com a realização de teleconsultas síncronas supervisionadas durante estágio realizado em um ambulatório-escola, durante o segundo semestre de 2021. Trata-se de pesquisa qualitativa que utilizou o software IRaMuTeQ® e "Análise do Conteúdo". Esses educandos pontuam entraves para a utilização das teleconsultas, destacando preocupações com a humanização, segurança da pessoa atendida e qualidade da consulta, mas visualizam potencialidades tais como a facilidade de acesso e a comodidade. Reconhecem a importância da prática durante sua Graduação em um mundo cada vez mais tecnológico, mas trazem inquietações relacionadas à perda do exame físico e à mercantilização da Medicina.


With the progress of technology, teleconsultation has become part of medical degree courses. This article presents the representations of a group of medical students from a university in the capital of the state of São Paulo regarding their experiences with supervised synchronous teleconsultations during an internship in a teaching clinic in the second semester of 2021. We conducted a qualitative study using the software IRaMuTeQ® and content analysis. The students highlighted barriers to the use of teleconsultation, emphasizing concerns with humanization, patient safety and consultation quality, but also perceived strengths such as ease of access and convenience. They recognize the importance of practice on the degree course in an ever more technological world, but raise concerns about the lack of physical examination and the commodification of medicine.


Con el avance de la tecnología, el aprendizaje en teleconsultas pasó a formar parte de la graduación médica actual. Esta investigación presenta las representaciones de un grupo de alumnos de un curso de medicina localizado en la capital del estado de São Paulo sobre sus experiencias con la realización de teleconsultas sincronizadas supervisadas durante una pasantía realizada en un ambulatorio escuela, durante el segundo trimestre de 2021. Se traba de una investigación cualitativa que utilizó el software IRaMuTeQ® y Análisis de Contenido. Estos alumnos puntúan obstáculos para la utilización de las teleconsultas, destacando preocupaciones con la humanización, seguridad de la persona atendida y calidad de la consulta, pero visualizan potencialidades tales como la facilidad de acceso y la comodidad. Reconocen la importancia de la práctica durante su graduación en un mundo cada vez más tecnológico, pero presentan inquietudes relacionadas a la pérdida del examen físico y a la mercantilización de la medicina.

9.
Rev. bras. enferm ; 77(supl.4): e20230041, 2024.
Artigo em Inglês | LILACS-Express | LILACS, BDENF - Enfermagem | ID: biblio-1569694

RESUMO

ABSTRACT Objective: to understand the bioethical perspectives on mobile tracking device use. Methods: theoretical study based on action research, carried out with eight graduate students from a public university. A focus group was used, with a thematic content analysis methodology with a codebook structure, approved by the Research Ethics Committee. Results: from the analysis, there was a concern about using devices after the pandemic ended. Using or not the device, rights inherent to humans, legislation and effectiveness of methods deepen interpretations, moving participants from a personalistic conception of the topic to a vision focused on professional implications about the methods. Final considerations: the debate on the impact of using technological devices on health, especially those that imply restriction of rights that refer to individuals' private life, involves a discussion of a professional nature, in addition to requirement for clear rules on the topic.


RESUMEN Objetivo: comprender las perspectivas bioéticas sobre el uso de dispositivos móviles de seguimiento. Métodos: estudio teórico basado en la investigación acción, realizado con ocho estudiantes de posgrado de una universidad pública. Se utilizó un grupo focal, con metodología de análisis de contenido temático con estructura de libro de códigos, aprobada por el Comité de Ética en Investigación. Resultados: del análisis surgió la preocupación por el uso de dispositivos una vez terminada la pandemia. El uso o no del dispositivo, los derechos inherentes a la persona humana, la legislación y la eficacia de los métodos profundizan las interpretaciones, trasladando a los participantes de una concepción personalista del tema a una visión centrada en las implicaciones profesionales de los métodos. Consideraciones finales: el debate sobre el impacto del uso de dispositivos tecnológicos en la salud, especialmente aquellos que implican restricción de derechos que se refieren a la vida privada de las personas, implica una discusión profesional, además de la exigencia de reglas claras sobre el tema.


RESUMO Objetivo: compreender as perspectivas bioéticas no uso de dispositivos móveis de rastreamento. Métodos: estudo teórico fundamentado através de pesquisa-ação, realizado com oito pós-graduandos de uma universidade pública. Utilizou-se grupo focal, com metodologia de análise de conteúdo temática com estrutura de codebook, aprovado pelo Comitê de Ética em Pesquisa. Resultados: a partir da análise, constatou-se uma preocupação sobre o uso dos dispositivos findada a pandemia. O uso ou não do dispositivo, direitos inerentes à pessoa humana, legislação e efetividade dos métodos aprofundam interpretações, passando os participantes de uma concepção personalista do tema a uma visão voltada a implicações profissionais sobre os métodos. Considerações finais: o debate sobre o impacto do uso de dispositivos tecnológicos na saúde, em especial os que impliquem restrição de direitos que se referem à vida privada do indivíduo, passa por uma discussão de caráter profissional, além da exigência de claro regramento sobre o tema.

10.
Braz. j. med. biol. res ; 57: e13105, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528108

RESUMO

One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.

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