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1.
Environ Toxicol Pharmacol ; 108: 104473, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759846

RESUMO

The most recent dam rupture in Brazil released tons of mining tailings into the upper course of the Paraopeba River, affecting this river in an unprecedented way. The present study aimed to evaluate the influence of heavy metals on Prochilodus costatus, an important commercial species in Brazil, four years after the dam colapse. To this end, biomarkers of heavy metals, oxidative stress, and environmental stress were analyzed, and histological analyses of target organs were performed. The results demonstrated critical contamination of fish from the Paraopeba River. Increased expression of Metallothioneins - MTs, Heat Shock Protein - HSP70, and inducible nitric oxide synthase - iNOS, as well as greater rates of histological changes in the liver, spleen, and gonads, were observed in P. costatus. These findings demonstrate that, despite past contamination, the metals present in mining tailings have significantly increased the contamination of the Paraopeba River basin.


Assuntos
Fígado , Metalotioneína , Metais Pesados , Óxido Nítrico Sintase Tipo II , Rios , Poluentes Químicos da Água , Animais , Metalotioneína/metabolismo , Poluentes Químicos da Água/toxicidade , Metais Pesados/toxicidade , Óxido Nítrico Sintase Tipo II/metabolismo , Brasil , Fígado/efeitos dos fármacos , Fígado/metabolismo , Baço/efeitos dos fármacos , Baço/metabolismo , Caraciformes/metabolismo , Masculino , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Peixes/metabolismo , Feminino
2.
Int Arch Otorhinolaryngol ; 28(2): e255-e262, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38618588

RESUMO

Introduction Obstructive sleep apnea (OSA) is a severe form of sleep-disordered breathing (SDB) that is strongly correlated with comorbidities, in which epiglottic collapse (EC) and other contributing factors are involved. Objectives To evaluate the occurrence of EC in OSA patients through drug-induced sleep endoscopy (DISE) and to determine the factors contributing to EC. Methods A retrospective study of 37 adult patients using medical history. Patients were assessed for laryngopharyngeal reflux (LPR) and lingual tonsil hypertrophy (LTH) using reflux symptom index and reflux finding score (RFS); for OSA using polysomnography, and for airway collapse through DISE. An independent t -test was performed to evaluate risk factors, including the involvement of three other airway structures. Results Most EC patients exhibited trap door epiglottic collapse (TDEC) (56.8%) or pushed epiglottic collapse (PEC) (29.7%). Lingual tonsil hypertrophy, RFS, and respiratory effort-related arousal (RERA) were associated with epiglottic subtypes. Laryngopharyngeal reflux patients confirmed by RFS (t(25) = -1.32, p = 0.197) tended to suffer PEC; LTH was significantly associated (X2(1) = 2.5, p = 0.012) with PEC (odds ratio [OR] value = 44) in grades II and III LTH patients; 11 of 16 TDEC patients had grade I LTH. Pushed epiglottic collapse was more prevalent among multilevel airway obstruction patients. A single additional collapse site was found only in TDEC patients. Conclusion Laryngopharyngeal reflux causes repetitive acid stress toward lingual tonsils causing LTH, resulting in PEC with grade II or III LTH. Trap door epiglottic collapse requires one additional structural collapse, while at least two additional collapse sites were necessary to develop PEC. Respiratory effort-related arousal values may indicate EC.

3.
Rev. ADM ; 81(2): 81-86, mar.-abr. 2024. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1561679

RESUMO

Introducción: el colapso trasversal maxilar se define como el desarrollo insuficiente del maxilar en sentido trasversal. Es uno de los problemas más perjudiciales en el crecimiento facial y la integridad de las estructuras dentoalveolares. Objetivo: identificar la cantidad colapsos transversales del maxilar en tomografía computarizada de haz cónico (CBCT) y la decisión terapéutica propuesta. Material y métodos: se examinó un total de 52 expedientes con CBCT del Postgrado de Ortodoncia de la Universidad Autónoma de Sinaloa determinándose los casos de colapso trasversal maxilar a través del análisis de Penn. La información recolectada fue capturada en una base de datos, utilizando el programa Excel, y se analizó con un modelo de regresión logística. Resultados: se encontraron 32 pacientes con colapso trasversal maxilar de un total 44 pacientes atendidos. El modelo de regresión logística no mostró asociación entre la presencia de colapso maxilar y el uso de tratamientos con el que resolvieran el colapso maxilar. Conclusión: existe gran cantidad de pacientes con colapso maxilar; sin embargo, el plan de tratamiento no muestra tratar de resolver estos colapsos maxilares (AU)


Introduction: transverse maxillary collapse is defined as insufficient development of the maxilla in a transverse direction. It is one of the most harmful problems in facial growth and the integrity of the dentoalveolar structures. Objective: identify the number of transverse collapses of the maxilla in cone beam computed tomography (CBCT) and the proposed therapeutic decision. Material and methods: a total of 52 records with CBCT of the orthodontics postgraduate course of the Autonomous University of Sinaloa UAS were examined, determining the cases of transverse maxillary collapse through the Pen analysis. The information collected was captured in a database using the Excel program and analyzed with a logistic regression model. Results: 32 patients with maxillary transverse collapse were found out of a total of 44 patients attended. The logistic regression model did not show an association between the presence of maxillary collapse and the use of treatments that resolved maxillary collapse. Conclusion: there is a large number of patients with maxillary collapse, however, the treatment plan does not show trying to resolve these maxillary collapses (AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Anormalidades Maxilomandibulares/terapia , Anormalidades Maxilomandibulares/diagnóstico por imagem , Faculdades de Odontologia , Modelos Logísticos , Estudos Transversais , Interpretação Estatística de Dados , Tomografia Computadorizada de Feixe Cônico Espiral/métodos , México/epidemiologia
4.
Conserv Biol ; 38(4): e14247, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38488677

RESUMO

Climate change is one of the most important drivers of ecosystem change, the global-scale impacts of which will intensify over the next 2 decades. Estimating the timing of unprecedented changes is not only challenging but is of great importance for the development of ecosystem conservation guidelines. Time of emergence (ToE) (point at which climate change can be differentiated from a previous climate), a widely applied concept in climatology studies, provides a robust but unexplored approach for assessing the risk of ecosystem collapse, as described by the C criterion of the International Union for Conservation of Nature's Red List of Ecosystems (RLE). We identified 3 main theoretical considerations of ToE for RLE assessment (degree of stability, multifactorial instead of one-dimensional analyses, and hallmarks of ecosystem collapse) and 4 sources of uncertainty when applying ToE methodology (intermodel spread, historical reference period, consensus among variables, and consideration of different scenarios), which aims to avoid misuse and errors while promoting a proper application of the framework by scientists and practitioners. The incorporation of ToE for the RLE assessments adds important information for conservation priority setting that allows prediction of changes within and beyond the time frames proposed by the RLE.


Perspectivas sobre el momento del colapso ecosistémico en un clima cambiante Resumen El cambio climático es uno de los principales causantes del cambio ecosistémico, cuyo impacto a escala global se intensificará en las próximas dos décadas. No sólo es un reto estimar el momento de los cambios sin precedentes, sino también es de gran importancia para el desarrollo de las directrices de conservación de los ecosistemas. El momento de aparición (MdA), el punto en el que el cambio climático puede diferenciarse de un clima previo; es un concepto de aplicación extensa en los estudios de climatología y proporciona una estrategia sólida pero poco explorada para evaluar el riesgo del colapso ecosistémico, como está descrito por el criterio C de la Lista Roja de Ecosistemas (LRE) de la Unión Internacional para la Conservación de la Naturaleza. Identificamos las tres consideraciones teóricas del MdA para la evaluación de la LRE (grado de estabilidad, análisis multifactoriales en vez de unidimensionales y distintivos del colapso ecosistémico) y cuatro fuentes de incertidumbre cuando se aplica la metodología MdA (difusión intermodelo, periodo de referencia histórica, consenso entre las variables y consideración de escenarios distintos), la cual busca evitar el mal uso y los errores mientras se promueve una aplicación adecuada del marco de los científicos y lo practicantes. La incorporación del MdA a las evaluaciones de la LRE añade información importante para el establecimiento de prioridades de conservación que permiten la predicción de cambios dentro y más allá del marco temporal propuesto por la LRE.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Fatores de Tempo , Incerteza
5.
J Control Release ; 367: 572-586, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301926

RESUMO

The cytoskeleton facilitates tumor cells invasion into the bloodstream via vasculogenic mimicry (VM) for "attack", and protects cells against external threats through cytoskeletal remodeling and tunneling nanotubes (TNTs) for "defense". However, the existing strategies involving cytoskeleton are not sufficient to eliminate tumor metastasis due to mitochondrial energy supply, both within tumor cells and from outside microenvironment. Here, considering the close relationship between cytoskeleton and mitochondria both in location and function, we construct a nano-platform that combats the "attack" and "defense" of cytoskeleton in the cascading metastasis. The nano-platform is composed of KFCsk@LIP and KTMito@LIP for the cytoskeletal collapse and mitochondrial dysfunction. KFCsk@LIP prevents the initiation and circulation of cascading tumor metastasis, but arouses limited suppression in tumor cell proliferation. KTMito@LIP impairs mitochondria to trigger apoptosis and impede energy supply both from inside and outside, leading to an amplified effect for metastasis suppression. Further mechanisms studies reveal that the formation of VM and TNTs are seriously obstructed. Both in situ and circulating tumor cells are disabled. Subsequently, the broken metastasis cascade results in a remarkable anti-metastasis effect. Collectively, based on the nano-platform, the cytoskeletal collapse with synchronous mitochondrial dysfunction provides a potential therapeutic strategy for cascading tumor metastasis suppression.


Assuntos
Doenças Mitocondriais , Neovascularização Patológica , Humanos , Neovascularização Patológica/tratamento farmacológico , Linhagem Celular Tumoral , Citoesqueleto/patologia , Movimento Celular
6.
Environ Res ; 248: 118240, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38266903

RESUMO

Monitoring of contaminant levels in wildlife over time is a tool for assessing the presence and persistence of environmental impacts at ecosystem, community and population levels. Tropical seabirds breeding in the Abrolhos Archipelago, 70 km off the Brazilian coast, forage in areas under the influence of the Doce River discharge. In 2015, the Fundão Dam collapsed and released ca 60 million tons of iron ore tailings into the ocean. In the present study, red-billed tropicbirds Phaethon aethereus and brown boobies Sula leucogaster breeding in Abrolhos were monitored over four years (2019-2022) for metal (Fe, Mn, Zn, Cu, Cr, Hg, Pb, Cd) and metalloid (As) concentrations in blood and feathers. Over six sampling events, metal (loid) concentrations showed strong temporal variation in both tissues. Overall, feathers showed greater element concentrations than blood, with stronger correlations between elements, especially Mn and the nonessential As, Cd, Hg and Pb. Mn is one of the major chemical markers of the Fundão Dam tailings. Metal (loid) concentrations in the tropical seabirds evaluated were above suggested threshold levels for most nonessential elements (As, Cd and Pb), especially in February 2021, when metal (loid) concentrations peaked in feathers. In this case, values were orders of magnitude higher than those observed in other sampling events. This occurred one year after a major rainy season in the Doce River basin, which increased river discharge of contaminated mud into the ocean, where contaminants are further remobilized by winds and currents, resulting in transference through the marine food web. This finding is consistent to what has been observed for other ecosystem compartments monitored in the region under the influence of the Doce River. Our findings highlight the utility of using tropical seabirds as sentinels of marine pollution, revealing strong temporal patterns in metal (loid) concentrations associated to bottom-up climatic processes.


Assuntos
Arsênio , Desastres , Mercúrio , Poluentes Químicos da Água , Animais , Arsênio/análise , Ecossistema , Plumas , Cádmio , Chumbo , Monitoramento Ambiental/métodos , Aves , Brasil , Rios , Poluentes Químicos da Água/análise
7.
Int. arch. otorhinolaryngol. (Impr.) ; 28(2): 255-262, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1558030

RESUMO

Abstract Introduction Obstructive sleep apnea (OSA) is a severe form of sleep-disordered breathing (SDB) that is strongly correlated with comorbidities, in which epiglottic collapse (EC) and other contributing factors are involved. Objectives To evaluate the occurrence of EC in OSA patients through drug-induced sleep endoscopy (DISE) and to determine the factors contributing to EC. Methods A retrospective study of 37 adult patients using medical history. Patients were assessed for laryngopharyngeal reflux (LPR) and lingual tonsil hypertrophy (LTH) using reflux symptom index and reflux finding score (RFS); for OSA using polysomnography, and for airway collapse through DISE. An independent t-test was performed to evaluate risk factors, including the involvement of three other airway structures. Results Most EC patients exhibited trap door epiglottic collapse (TDEC) (56.8%) or pushed epiglottic collapse (PEC) (29.7%). Lingual tonsil hypertrophy, RFS, and respiratory effort-related arousal (RERA) were associated with epiglottic subtypes. Laryngopharyngeal reflux patients confirmed by RFS (t(25) = −1.32, p = 0.197) tended to suffer PEC; LTH was significantly associated (X2(1) = 2.5, p = 0.012) with PEC (odds ratio [OR] value = 44) in grades II and III LTH patients; 11 of 16 TDEC patients had grade I LTH. Pushed epiglottic collapse was more prevalent among multilevel airway obstruction patients. A single additional collapse site was found only in TDEC patients. Conclusion Laryngopharyngeal reflux causes repetitive acid stress toward lingual tonsils causing LTH, resulting in PEC with grade II or III LTH. Trap door epiglottic collapse requires one additional structural collapse, while at least two additional collapse sites were necessary to develop PEC. Respiratory effort-related arousal values may indicate EC.

8.
Healthcare (Basel) ; 11(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37958018

RESUMO

Obstructive Sleep Apnea (OSA) is characterized by repetitive collapse of the upper airway during sleep. Drug-Induced Sleep endoscopy (DISE) is used to identify the collapse site. Among the possible sites of collapse, the epiglottis occurs more frequently than previously described. In this study, we reviewed DISE findings and classified different epiglottic collapse patterns. We found 104 patients (16.4%) with epiglottis collapse (primary 12.5% and secondary 3.9%). We described the following patterns of epiglottis collapse: Anterior-Posterior (AP) collapse with rigid component "trapdoor type" (48%); AP collapse with lax component "floppy type" (13.5%); Lateral- Lateral (LL) collapse with omega shape component "book type" (14.5%); and secondary due to lateral pharyngeal wall or tongue base collapse (24%). The identification of the epiglottic collapse pattern is crucial in decision-making when attempting to ameliorate OSA. These findings in OSA phenotyping could influence the type of treatment chosen.

9.
Proc Natl Acad Sci U S A ; 120(39): e2306987120, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37722053

RESUMO

Mass extinctions during the past 500 million y rapidly removed branches from the phylogenetic tree of life and required millions of years for evolution to generate functional replacements for the extinct (EX) organisms. Here we show, by examining 5,400 vertebrate genera (excluding fishes) comprising 34,600 species, that 73 genera became EX since 1500 AD. Beyond any doubt, the human-driven sixth mass extinction is more severe than previously assessed and is rapidly accelerating. The current generic extinction rates are 35 times higher than expected background rates prevailing in the last million years under the absence of human impacts. The genera lost in the last five centuries would have taken some 18,000 y to vanish in the absence of human beings. Current generic extinction rates will likely greatly accelerate in the next few decades due to drivers accompanying the growth and consumption of the human enterprise such as habitat destruction, illegal trade, and climate disruption. If all now-endangered genera were to vanish by 2,100, extinction rates would be 354 (average) or 511 (for mammals) times higher than background rates, meaning that genera lost in three centuries would have taken 106,000 and 153,000 y to become EX in the absence of humans. Such mutilation of the tree of life and the resulting loss of ecosystem services provided by biodiversity to humanity is a serious threat to the stability of civilization. Immediate political, economic, and social efforts of an unprecedented scale are essential if we are to prevent these extinctions and their societal impacts.


Assuntos
Ecossistema , Extinção Biológica , Animais , Humanos , Filogenia , Efeitos Antropogênicos , Biodiversidade , Mamíferos
10.
Odontol. vital ; jun. 2023.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1431019

RESUMO

Introducción. La atresia o estrechez del maxilar superior es una patología de origen multifactorial que genera un colapso transversal, el mismo e implica la carencia de espacio necesario para la disposición correcta de las piezas dentales. Objetivo. El presente artículo está enmarcado en una revisión narrativa de la literatura, con el objetivo de describir el abordaje terapéutico del colapso transversal del maxilar superior con microimplantes (TAD´s), determinando los efectos esqueléticos y dentoalveolares en el maxilar superior, así como las ventajas y desventajas del tratamiento. Método. La búsqueda de artículos se realizó a través de mediante las plataformas de: Scielo, PubMed, Google Académico y Medline. Se seleccionaron 21 artículos cuyos textos completos fueron descargados para examinarlos a detalle y verificar que cumplieran con todos los criterios de inclusión, de los cuales se obtuvieron 16 artículos para elaborar esta revisión narrativa. Conclusiones. El abordaje terapéutico del colapso transversal se produce por medio de la expansión rápida del maxilar (ERM) o disyunción maxilar, en pacientes jóvenes en crecimiento; y en los pacientes adultos se suele emplear un tratamiento con técnica MARPE con microimplantes (TAD´s). El principal efecto esquelético es la apertura de la sutura maxilar que varía de 2 a 10 mm, muchos autores coinciden en que el manejo del colapso transversal del maxilar superior con microimplantes no genera efectos dentoalveolares negativos, al contrario, tiene ventajas biomecánicas debido al anclaje con el hueso, reduciendo el riesgo de movimiento dentales indeseados y permitiendo un control del crecimiento vertical.


Introduction. The atresia or narrowness of the upper jaw is a pathology of multifactorial origin that generates a transverse collapse, it implies the lack of space necessary for the correct arrangement of the dental pieces. Objective. This article is framed in a narrative review of the literature, with the aim of describing the therapeutic approach of transverse maxillary collapse with microimplants (TAD's), determining the skeletal and dentoalveolar effects in the maxilla, as well as the advantages and disadvantages of treatment. Method. The search for articles was carried out through the following platforms: Scielo, PubMed, Google Scholar and Medline. 21 articles whose full texts were downloaded were selected to examine them in detail and verify that they met all the inclusion criteria, of which 18 articles were obtained to prepare this narrative review. Conclusions. The therapeutic approach to transverse collapse occurs through rapid maxillary expansion (RME) or maxillary disjunction, in young growing patients; and in adult patients, treatment with the MARPE technique with microimplants (TAD's) is usually used. The main skeletal effect is the opening of the maxillary suture, which varies from 2 to 10 mm. Many authors agree that the management of the transverse collapse of the maxilla with microimplants does not generate negative dentoalveolar effects, on the contrary, it has biomechanical advantages due to the anchorage with the bone, reducing the risk of unwanted dental movement and allowing control of vertical growth.


Assuntos
Implantes Dentários , Maxila
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