Impact of the pulvinar on the ventral pathway of the cat visual cortex

Signals from the retina are relayed to the lateral geniculate nucleus from which they are sent to the primary visual cortex. At the cortical level, the information is transferred across several visual areas in which the complexity of the processing increases progressively. Anatomical and functional evidence demonstrate the existence of two main pathways in visual cortex processing distinct features of the visual information: the dorsal and ventral streams. Cortical areas composing the dorsal stream are implicated mostly in motion processing while those comprising the ventral stream are involved in the processing of form and colour. This classic view of the cortical functional organization is challenged by the existence of reciprocal connections of visual cortical areas with the thalamic nucleus named pulvinar. These connections allow the creation of a trans-thalamic pathway that parallels the cortico-cortical communications across the visual hierarchy. The main goal of the present thesis is twofold: first, to obtain a better comprehension of the processing of light increments and decrements in an area of the cat ventral stream (area 21a); second, to characterize the nature of the thalamo-cortical inputs from the cat lateral posterior nucleus (LP) to area 21a. In study #1, we investigated the spatiotemporal response profile of neurons from area 21a to light increments (brights) and decrements (darks) using a reverse correlation analysis of a sparse noise stimulus. Our findings showed that 21a neurons exhibited stronger responses to darks with receptive fields exhibiting larger dark subfields. However, no differences were found between the temporal dynamics of brights and darks. In comparison with the primary visual cortex, the dark preference in area 21a was found to be strongly enhanced, supporting the notion that the asymmetries between brights and darks are transmitted and amplified along the ventral stream. In study #2, we investigated the impact of the reversible pharmacological inactivation of the LP nucleus on the contrast response function (CRF) of neurons from area 21a and the primary visual cortex (area 17). The thalamic inactivation yielded distinct effects on both cortical areas. While in area 17 the LP inactivation caused a slight decrease in the response gain, in area 21a a strong increase was observed. Thus, our findings suggest that the LP exerts a modulatory influence on the cortical processing along the ventral stream with stronger impact on higher order extrastriate areas. Taken together, our findings allowed a better comprehension of the functional properties of the cat ventral stream and contributed to the current knowledge on the role of the pulvinar on the cortico-thalamo-cortical processing of visual information.Les signaux provenant de la rétine sont relayés dans le corps géniculé latéral où ils sont envoyés au cortex visuel primaire. L’information passe ensuite à travers plusieurs aires visuelles où la complexité du traitement augmente progressivement. Des données tant anatomiques que fonctionnelles ont démontré l’existence de deux voies principales qui traitent différentes propriétés de l’information visuelle : les voies dorsale et ventrale. Les aires corticales composant la voie dorsale sont impliquées principalement dans le traitement du mouvement tandis que les aires de la voie ventrale sont impliquées dans le traitement de la forme et de la couleur. Cette vision classique de l’organisation fonctionnelle du cortex est toutefois remise en question par l’existence de connections réciproques entre les aires corticales visuelles et le pulvinar, un noyau thalamique. En effet, ces connections permettent la création d’une voie trans-thalamique parallèle aux connections cortico-corticales à travers la hiérarchie visuelle. Le but principal de la présente thèse consiste en deux volets : le premier est d’obtenir une meilleure compréhension du traitement des incréments et décréments de la lumière dans une aire de la voie ventrale du chat (aire 21a); le second est de caractériser la nature des inputs thalamo-corticaux du noyau latéral postérieur (LP) à l’aire 21a chez le chat. Dans l’étude #1, nous avons investigué le profil spatiotemporel des réponses des neurones de l’aire 21a aux incréments (blancs) et décréments (noirs) de lumière en utilisant l’analyse de corrélation inverse d’un stimulus de bruit épars. Les neurones de l’aire 21a ont répondu plus fortement aux stimuli noirs, en montrant des champs récepteurs avec des sous-champs noirs plus larges. Cependant, aucune différence n’a été trouvée en ce qui concerne les dynamiques temporelles des réponses aux blancs et aux noirs. En comparaison avec le cortex visuel primaire, la préférence aux stimuli noirs dans l’aire 21a s’est avérée fortement augmentée. Ces données indiquent que les asymétries entre les réponses aux blancs et aux noirs sont transmises et amplifiées à travers la voie ventrale. Dans l’étude #2, nous avons investigué l’impact de l’inactivation pharmacologique réversible du noyau LP sur la fonction de réponse au contraste (CRF) des neurones de l’aire 21a et du cortex visuel primaire (aire 17). L’inactivation a eu différents effets dans les deux aires corticales. Alors que, dans l’aire 17, l’inactivation du LP a causé une légère réduction du gain de la réponse, une forte augmentation a été observée dans l’aire 21a. Ainsi, nos résultats suggèrent que le LP exerce une influence modulatrice dans le traitement cortical à travers la voie ventrale avec un impact plus important dans des aires extrastriées de plus haut niveau. Nos résultats ont permis d’avoir une meilleure compréhension des propriétés fonctionnelles de la voie ventrale du chat et de contribuer à enrichir les connaissances actuelles sur le rôle du pulvinar dans le traitement cortico-thalamo-cortical de l’information visuelle

The Impact of Sex and Performance Level on Pacing Behavior in a 24-h Ultramarathon

Purpose: We analyzed the impact of sex, performance level and substantial speed reductions (SSR) on pacing in the VI Rio 24-h Marines Ultramarathon. This will provide insights into the importance of minimizing speed variations in relation to optimal pacing in endurance events. Methods: Runners (30 males and 21 females), classified as high- (HP) and low-performance (LP) ran the race while having their time recorded every 400 m. The pacing was analyzed as the first 10% (initial epoch), the following 80% (intermediate epoch) and the last 10% of the race (final epoch). The time percentage spent at speeds 8.0 km·h−1 (running speed) was calculated. Results: Runners showed a reverse J-shaped pacing (P < 0.001) regardless of sex and performance level, although male (P < 0.004) and HP runners (P < 0.001) have preserved a higher mean speed throughout the race. Male and HP runners spent more time at running speed (P < 0.001) and less time at SSR (P < 0.001) than female and LP runners. Total distance was inversely correlated with the number of SSR and speed CV in male (r = −0.47 and r = −0.64, respectively) and female (r = −0.61 and r = −0.47, respectively). Conclusion: Male, HP runners showed less SSR, conserving a higher mean speed with less variation throughout the race. Results suggest that conservative pacing strategies, with lower speeds in the beginning and higher speeds toward the end, may be the most adequate for different endurance running disciplines. Results also show different competition dynamics between men and women, which warrants further exploration in ultramarathons as well as other IAAF events

Numerical Study of Turbulent Flows and Heat Transfer in Coupled Industrial-Scale Tundish of a Continuous Casting Material in Steel Production

This chapter describes the numerical simulations of a coupled industrial scale of the tundish and continuous casting process. The governing equations are presented, and the numerical procedure is discussed in a common framework. The coupled solutions are presented for the transient turbulent flows within the tundish, solidifying zone and extracting regions with the coupling phenomena of heat and mass transfer. The tundish region flow and refractory are calculated using the inlet and outlet boundary conditions in order to estimate the filling phenomena. The transitions and cooling zones for the thin slab continuous casting process are designed to account for the control of the solidified skin in order to avoid breakout. We compared the numerical predictions of the temperatures with industrial monitoring data for a reference case in order to verify the consistence of the model predictions. A parallel version of the numerical code is proposed aiming to improve the computation time keeping numerical accuracy

Repercussões da Insuficiência Renal Crônica no Contexto Biopsicossocial de Pessoa em Tratamento Hemodialítico.

Introduction: chronic renal failure is considered an important public health problem since both the disease and the treatment have profound impacts on the entire life context of the affected person. Objective: to understand the repercussions of chronic renal failure in the biopsychosocial context of patients undergoing hemodialysis. Methodology: this is a descriptive, qualitative study developed in a regional reference hospital for the treatment of hemodialysis in the State of Bahia, Brazil. Twenty people with chronic renal failure undergoing hemodialysis took part in the study; all of them were over 18 years old. The data collection was carried out in December 2019 through a semi-structured interview. Subsequently, the data were systematized through Content Analysis. Results: the study showed that renal failure brings multidimensional repercussions to the patients due to the difficulties in entering the world market, difficulties related to food and water restrictions, limitations related to leisure and the physical activity practices, and the impact on sexuality. However, despite the limitations caused by the disease, patients showed themselves resilient in highlighting the importance of the treatment to guarantee their quality of life. Conclusion: the study points to the need of building specific policies aimed at reducing the impact caused by chronic renal failure since it is a chronic and irreversible disease that requires permanent treatment. Furthermore, the findings confirm the need for individualized assessment and the provision of holistic and humanized care by health professionals as a way to minimize the impact of the illness.Introducción: La insuficiencia renal crónica es considerada un importante problema de salud pública, ya que tanto la enfermedad como el tratamiento tienen profundos impactos en todo el contexto de vida de la persona afectada. Objetivo: Comprender las repercusiones de la insuficiencia renal crónica en el contexto biopsicosocial de personas en hemodiálisis. Metodología: Se trata de un estudio descriptivo, cualitativo, desarrollado en un hospital regional de referencia para el tratamiento de hemodiálisis en el Estado de Bahía, Brasil. En el estudio participaron 20 personas con insuficiencia renal crónica, mayores de 18 años, sometidas a hemodiálisis. La recolección de datos se realizó durante el mes de diciembre de 2019, a través de una entrevista semiestructurada. Posteriormente, los datos fueron sistematizados mediante análisis de contenido. Resultados: Se demostró que la insuficiencia renal trae repercusiones multidimensionales para las personas, debido a las dificultades para ingresar al mundo laboral, dificultades relacionadas con las restricciones alimentarias y hídricas, limitaciones relacionadas con el ocio y la práctica de actividad física e impactos en el ejercicio de la sexualidad. Sin embargo, a pesar de las limitaciones provocadas por la enfermedad, las personas se mostraron resilientes al resaltar la importancia del tratamiento para garantizar su calidad de vida. Conclusión: El estudio apunta a la necesidad de construir políticas específicas orientadas a reducir los impactos provocados por la insuficiencia renal crónica, por ser una enfermedad crónica e irreversible, que necesita tratamiento permanente. Además, los hallazgos confirman la necesidad de una evaluación individualizada y la provisión de atención integral y humanizada por parte de profesionales de la salud que les brindan atención, como una forma de minimizar los impactos de la enfermedad.Introdução: a insuficiência renal crônica é considerada um importante problema de saúde pública, uma vez que tanto a doença quanto o tratamento provocam impactos profundos em todo o contexto de vida da pessoa acometida. Objetivo: compreender as repercussões da insuficiência renal crônica no contexto biopsicossocial de pacientes em tratamento hemodialítico. Metodologia: trata-se de um estudo descritivo, qualitativo, desenvolvido em um hospital referência regional para o tratamento de hemodiálise no Estado da Bahia, Brasil. Participaram do estudo 20 pessoas com insuficiência renal crônica, com idade superior a 18 anos, em tratamento hemodialítico. A coleta dos dados foi realizada durante o mês de dezembro de 2019 através de uma entrevista semiestruturada. Posteriormente, os dados foram sistematizados através da Análise de Conteúdo. Resultados: evidenciou-se que a insuficiência renal traz repercussões multidimensionais para os pacientes, devido às dificuldades de inserção no mundo do trabalho, dificuldades relacionadas às restrições alimentares e hídricas, limitações relacionadas ao lazer e a prática de atividade física e impactos no exercício da sexualidade. Entretanto, apesar das limitações provocadas pela doença, os pacientes mostraram-se resilientes ao destacarem a importância do tratamento para garantia de sua qualidade de vida. Conclusão: o estudo aponta para necessidade de construção de políticas específicas voltadas para redução dos impactos provocados pela Insuficiência&nbsp;Renal Crônica, uma vez que se trata de uma doença crônica e irreversível, com necessidade de tratamento permanente. Além disso, os achados ratificam a necessidade de avaliação individualizada e oferta de uma assistência holística e humanizada por parte dos profissionais de saúde como forma de minimizar os impactos do adoecimento

Conhecendo a hipomineralização molar-incisivo: do diagnóstico ao tratamento

A hipomineralização molar-incisivo (HMI) é determinada como uma anomalia dentária causada por uma interferência da maturação do esmalte dental, no final da amelogênese. Esse defeito pode acometer um ou até os quatro primeiros molares permanentes, frequentemente associado aos incisivos e dentes decíduos. A doença cárie e a hipersensibilidade são as principais consequências desse defeito, pois a HMI leva a uma fragilidade e porosidade do esmalte dentário, ocasionando possíveis fraturas que se tornam áreas retentivas de biofilme e facilitando o desenvolvimento de lesões cariosas. Clinicamente, os dentes acometidos possuem opacidade e coloração variadas, podendo apresentar-se como manchas amarelo-amarronzadas bem demarcadas, o que leva à perda progressiva da estrutura do esmalte que pode vir acompanhada de fraturas dentais de uma parte do elemento dentário. Estas características clínicas são cruciais para a classificação da doença, podendo variar de leve à severa. Trata-se de um defeito qualitativo que pode gerar impactos negativos na qualidade de vida do paciente, ocasionando problemas estéticos, sensibilidade e doença cárie. Sobre a etiologia da HMI, ainda está indefinida, mas possuem alguns fatores que podem estar associados a este defeito, como por exemplo: prematuridade, baixo peso ao nascimento, hipóxia, doenças respiratórias, doenças metabólicas do cálcio ou fosfato, doenças da infância associadas à febre alta, doenças gastrointestinais, dentre outras. Como a HMI possui similaridade com outros defeitos, o cirurgião dentista deve estar capacitado para realizar o diagnóstico, conhecendo as características clínicas desta anomalia e sabendo diferenciá-la das demais lesões, para que se estabeleça um correto tratamento que atenda às necessidades especificas de cada paciente. O presente estudo objetivou revisar a literatura para apresentar as possíveis causas da hipomineralização molar-incisivo, bem como seus sinais clínicos, diagnósticos e tratamentos para esse defeito de esmalte

Incorporating costs, thresholds and spatial extents for selecting stream bioindicators in an ecotone between two Brazilian biodiversity hotspots

Biomonitoring is critical for characterizing and monitoring status, spatial patterns, and long-term trends in the ecological condition of freshwater ecosystems. The selection of cost-effective bioindicators is a critical step in establishing such monitoring programs. Key indicator considerations are a reliable response to anthropogenic disturbances, a high benefit-cost-ratio and sensitivity at multiple spatial extents. We evaluated non-linear responses of Ephemeroptera, Plecoptera and Trichoptera (EPT) and fish to the effects of native vegetation loss within buffers of 100 m and 1000 m and assessed the sampling and processing costs involved for each assemblage. We sampled 37 neotropical stream sites in the Formoso River network, a karstic region of the Bodoquena Plateau, midwest Brazil, lying in the ecotone between the Cerrado and Atlantic Forest biological hotspots. We used TITAN (threshold indicator taxa analysis) to identify six indicator taxa, four EPT genera and two fish species. The four EPT genera had low negative thresholds to native vegetation loss, whereas the two fish species had positive thresholds. Thresholds were lower for the 100 m buffers than the 1000 m buffers for EPT. The most sensitive taxon (Macronema, Trichoptera) had a threshold of 0% native vegetation loss in the 100 m buffers and nearly 40% in the 1000 m buffers. For taxa richness, we found no non-linear response to the effects of native vegetation loss for buffer extent nor assemblage. The total cost for EPT biomonitoring was US$3,616; whereas for fish, the total was US$ 1,901. Although fish were less expensive than EPT, they did not respond negatively to native vegetation loss and their positive threshold started at 48%, a level of vegetation loss that was highly disruptive of EPT. Therefore, we do not recommend using fish to monitor the effects of native vegetation loss on headwater streams in the Bodoquena Plateau. Although EPT monitoring costs 52% more than fish assemblage monitoring, it detected earlier impacts of the effects of native vegetation loss on stream biota, especially in the 100 m buffer. Therefore, EPT are more cost-effective early warning indicators for monitoring the effects of native vegetation loss in Bodoquena Plateau headwaters

Composição florística da regeneração natural de área de cerrado sensu stricto e sub-bosque de clones de eucalipto

O Cerrado é o segundo bioma mais importante do Brasil, conhecido principalmente devido a sua biodiversidade, dentre os estados brasileiros o Tocantins se destaca por possuir a maior quantidade de remanescentes deste bioma. O objetivo desse trabalho foi avaliar a composição florística da regeneração natural de uma área de cerrado sensu stricto (c.s.s) e o sub-bosque de dois povoamentos de Eucalyptus urocam (E. uc) e E. urograndis (E. ug), além de comparar a riqueza e diversidade das espécies e a similaridade entre as áreas. Esse estudo foi conduzido na zona rural do município de Aliança do Tocantins (TO), nos limites da propriedade privada Nossa Senhora Aparecida. Foram instaladas aleatoriamente três parcelas amostrais de 20 x 50 m em três áreas experimentais, perfazendo um total de 3000 m² ou 0,3 ha em cada área experimental. Foram amostrados todos os indivíduos com altura ≥ a 1 m e ≤ a 3 m e circunferência na altura do solo ≥ a 10 cm. Foram identificados nas três áreas experimentais um total de 74 espécies, 31 famílias e 61 gêneros. Na área (c.s.s) foram amostradas 56 espécies, 24 famílias e 49 gêneros, na área (E. uc) foram encontradas 20 espécies, 15 famílias e 19 gêneros, e na área (E. ug) 27 espécies, 18 famílias e 24 gêneros. O índice de diversidade de Shannon (H’) encontrado foi 3,10; 2,87 e 2,36 e equabilidade de Pielou (J’) foi 0,77; 0,96 e 0,72, respectivamente, para as três áreas. A maior similaridade florística encontrada foi entre as áreas de E. uc e E. ug (46%) e a menor entre as áreas (c.s.s) e E. uc (21%)

Concentrations of indolebutyric acid on air-layering of guava cv. Paluma

Nowadays, the predominant technique for the commercial propagation of guava seedlings is through cuttings, using herbaceous cuttings that need a specialized infrastructure with intermittent misting, clean water, exhausters, water filters, and fans. As an alternative to plant propagation by cuttings, this study aimed to evaluate the influence of concentrations of indolebutyric acid (IBA) on the rooting of branches of the guava cv. Paluma by air-layering. The experimental design was in randomized blocks, with four replications and 10 air layers per plot. The treatments consisted of six concentrations of IBA powder mixed with industrial talcum: 0, 1,000, 2,000, 3,000, 4,000, and 5,000 mg.kg-1. Four adult guava parents that were in the off-season period were used. For the preparation of the air layers, the stems were girdled with a 4.0 cm width, using a steel blade, by removing the bark until exposing the cambium region, followed by IBA application and wrapping of the branches with a plastic bag containing moist organic substrate. The following variables were evaluated 120 days after air-layering: percentage of rooted and callused air layers, longest root length, and root dry matter. The analysis of variance indicated no significant differences between the IBA concentrations for all variables, but the rooting percentages were high (68.6 to 92.2%) regardless of the application of the exogenous auxin.Nowadays, the predominant technique for the commercial propagation of guava seedlings is through cuttings, using herbaceous cuttings that need a specialized infrastructure with intermittent misting, clean water, exhausters, water filters, and fans. As an alternative to plant propagation by cuttings, this study aimed to evaluate the influence of concentrations of indolebutyric acid (IBA) on the rooting of branches of the guava cv. Paluma by air-layering. The experimental design was in randomized blocks, with four replications and 10 air layers per plot. The treatments consisted of six concentrations of IBA powder mixed with industrial talcum: 0, 1,000, 2,000, 3,000, 4,000, and 5,000 mg.kg-1. Four adult guava parents that were in the off-season period were used. For the preparation of the air layers, the stems were girdled with a 4.0 cm width, using a steel blade, by removing the bark until exposing the cambium region, followed by IBA application and wrapping of the branches with a plastic bag containing moist organic substrate. The following variables were evaluated 120 days after air-layering: percentage of rooted and callused air layers, longest root length, and root dry matter. The analysis of variance indicated no significant differences between the IBA concentrations for all variables, but the rooting percentages were high (68.6 to 92.2%) regardless of the application of the exogenous auxin

Landsat sub-pixel land cover dynamics in the Brazilian Amazon

The Brazilian Amazon land cover changes rapidly due to anthropogenic and climate drivers. Deforestation and forest disturbances associated with logging and fires, combined with extreme droughts, warmer air, and surface temperatures, have led to high tree mortality and harmful net carbon emissions in this region. Regional attempts to characterize land cover dynamics in this region focused on one or two anthropogenic drivers (i.e., deforestation and forest degradation). Land cover studies have also used a limited temporal scale (i.e., 10–15 years), focusing mainly on global and country-scale forest change. In this study, we propose a novel approach to characterize and measure land cover dynamics in the Amazon biome. First, we defined 10 fundamental land cover classes: forest, flooded forest, shrubland, natural grassland, pastureland, cropland, outcrop, bare and impervious, wetland, and water. Second, we mapped the land cover based on the compositional abundance of Landsat sub-pixel information that makes up these land cover classes: green vegetation (GV), non-photosynthetic vegetation, soil, and shade. Third, we processed all Landsat scenes with &lt;50% cloud cover. Then, we applied a step-wise random forest machine learning algorithm and empirical decision rules to classify intra-annual and annual land cover classes between 1985 and 2022. Finally, we estimated the yearly land cover changes in forested and non-forested ecosystems and characterized the major change drivers. In 2022, forest covered 78.6% (331.9 Mha) of the Amazon biome, with 1.4% of secondary regrowth in more than 5 years. Total herbaceous covered 15.6% of the area, with the majority of pastureland (13.5%) and the remaining natural grassland. Water was the third largest land cover class with 2.4%, followed by cropland (1.2%) and shrubland (0.4%), with 89% overall accuracy. Most of the forest changes were driven by pasture and cropland conversion, and there are signs that climate change is the primary driver of the loss of aquatic ecosystems. Existing carbon emission models disregard the types of land cover changes presented in the studies. The twenty first century requires a more encompassing and integrated approach to monitoring anthropogenic and climate changes in the Amazon biome for better mitigation, adaptation, and conservation policies

Perfil de morbimortalidade dos profissionais de enfermagem por COVID-19 no Brasil entre os anos de 2020 e 2022

Introduction: The global repercussion of the COVID-19 pandemic raises the need to understand the impact of the disease among nursing professionals, as they were responsible for direct care of infected people. Objective: To describe the morbimortality profile of nursing professionals due to COVID-19 in Brazil between 2020 and 2022. Methodology: An epidemiological study conducted with data collected at the Nursing Observatory of the Federal Council of Nursing. The data were tabulated using version 21 of the SPSS software and analyzed by descriptive analysis, using frequencies. Results: During the period analyzed, 64 610 cases of COVID-19 were reported among Nursing professionals in Brazil. Of these, 36 425 (56.4 %) were confirmed and 833 died, representing a case fatality rate of 2.29 %. In terms of cases, COVID-19 was prevalent among women (84.24 %) aged between 31 and 40 (41.34 %) years, residing in the southeastern part of the country (29.77%) and infected in 2020 (66.79 %). As for deaths, the prevalence of cases occurred in 2020 (52.10 %) among women aged 41 to 50 years (68.07 %), residing in the northern region of Brazil (28.93 %). Nursing professionals had a 14 % higher mortality rate than the general population of Brazil, with a higher frequency among men. Conclusion: The study raises the need to build public policies aimed at protecting these workers. Such policies must seek to guarantee better working conditions, ongoing education, and to address gender inequalities.Introducción: La repercusión global de la pandemia COVID-19 plantea la necesidad de comprender el impacto de la enfermedad entre profesionales de enfermería, responsables del cuidado directo de las personas infectadas. Objetivo: Describir el perfil de morbimortalidad de profesionales de enfermería por COVID-19 en Brasil entre 2020 y 2022. Metodología: Estudio epidemiológico, realizado con datos recolectados en el Observatorio de Enfermería del Consejo Federal de Enfermería. Los datos fueron tabulados en el software SPSS versión 21 y analizados mediante análisis descriptivo, por frecuencias. Resultados: Durante el período analizado, se notificaron 64 610 casos de COVID-19 entre profesionales de enfermería en Brasil. De ellos, 36 425 (56.4 %) fueron confirmados y 833 fallecieron, lo que representó una tasa de letalidad del 2.29 %. En cuanto a la enfermedad, la COVID-19 fue prevalente entre mujeres (84.24 %), con edades entre 31 y 40 (41.34 %) años, residentes en el sureste del país (29.77 %) y contagiadas en 2020 (66.79 %). En cuanto a las defunciones, la prevalencia de casos ocurrió en 2020 (52.10 %), entre mujeres de 41 a 50 años (68.07 %), residentes en la región Norte de Brasil (28.93 %). La población profesionales de enfermería tuvo una tasa de mortalidad 14 % mayor que la de la población general de Brasil, con mayor frecuencia entre los hombres. Conclusión: El estudio plantea la necesidad de construir políticas públicas dirigidas a proteger a estas personas trabajadoras. Dichas políticas deben buscar garantizar mejores condiciones laborales, educación permanente y combatir las desigualdades de género.Introdução: A repercussão global da pandemia da COVID-19 levanta a necessidade de compreensão do impacto da doença entre os profissionais de enfermagem, uma vez que eram responsáveis pelo cuidado direto às pessoas contaminadas. Objetivo: Descrever o perfil de morbimortalidade dos profissionais de enfermagem por COVID-19 no Brasil entre os anos de 2020 e 2022. Metodologia: Estudo epidemiológico, realizado com dados coletados no Observatório da Enfermagem do Conselho Federal de Enfermagem. Os dados foram tabulados no software SPSS versão 21 e analisados mediante análise descritiva, por meio de frequências. Resultados: Durante o período analisado foram reportados 64.610 casos de COVID-19 entre os profissionais de Enfermagem no Brasil. Desses, 36.425 (56,4%) foram confirmados e 833 evoluíram para óbito, o que representou uma taxa de letalidade de 2,29%. No que se refere ao acometimento da doença, a COVID-19 mostrou-se prevalente entre mulheres (84,24%), na faixa etária de 31 a 40 (41,34%) anos, residentes no sudeste do país (29,77%) e infectadas no ano de 2020 (66,79%). Com relação aos óbitos, a prevalência dos casos ocorreu em 2020 (52,10%), entre mulheres, de 41 a 50 anos (68,07%), residentes na região Norte do Brasil (28,93%). Os profissionais de enfermagem tiveram letalidade 14% maior do que na população geral do Brasil, com maior frequência entre homens. Conclusão: O estudo levanta a necessidade de efetivação de políticas públicas voltadas para a proteção desses trabalhadores. Tais políticas devem buscar garantir melhores condições de trabalho, educação permanente e combate às desigualdades de gênero