A importância do modelo de monocamada lipídica da membrana plasmática de archaea para o ensino de biologia celular no brasil

In Biology, a cell is a functional unit of living organisms. Its constituents are mainly genetic material, cytoplasm, and the cell membrane. These three structural components play, among other biological roles, cell reproduction and maintenance, support of a metabolic activity, and maintenance of the physical-chemical barrier. Therefore, to understand a cell structure and its physiology is imperative to study the processes in which these components are involved. In Brazilian higher education, these topics are mainly addressed in Cellular and Molecular Biology subjects, but most of the contents focused on studying the structure, composition, and evolution of the plasma membrane, often referred to generically as the cell membrane. In some clades in Archaea, one of the three domains of life, the cell membrane promotes unique physiological characteristics that confer the evolutionary success of these groups and their survival in environments inhospitable to other lifeways. In these cells, the plasma membranes differ structurally from the membranes of the Bacteria and Eukarya domains which are organized in monolayers, presenting variations in carbon aliphatic chains size, carbon-carbon bonds, and have exclusive structural components such as Glycerol-dialkyl-glycerol-tetraethers (GDGT’s) and Arqueols. Unfortunately, little importance usually occurs to the Archaea domain in the chairs offered to Biological Sciences students. The objective of this work was to compile information about the Archaea membrane and enrich the current literary repertoire used to teach the modules related to the plasma membrane in the disciplines of Cellular and Molecular Biology in Brazil.En Biología, la célula se considera la unidad funcional de los seres vivos. Sus componentes son fundamentalmente: material genético, citoplasma y membrana plasmática. Estos tres componentes estructurales desempeñan, entre otras funciones biológicas, la reproducción y el mantenimiento celular, el soporte de la actividad metabólica y el mantenimiento de la barrera fisicoquímica. Por tanto, para comprender la fisiología y estructura celular, es imperativo estudiar los procesos en los que están involucrados estos componentes. En el ámbito de la educación superior brasileña, estos temas se tratan principalmente en las disciplinas de Biología Celular y Molecular. Gran parte del contenido de dicha disciplina se dedica al estudio de la estructura, composición y evolución de la membrana plasmática, a menudo denominada de forma genérica como membrana celular. En algunos clados de Archaea, uno de los tres dominios de la vida, la membrana celular promueve características fisiológicas únicas que permiten el éxito evolutivo de dichos grupos y su supervivencia en ambientes inhóspitos para otras formas de vida. En estas células, las membranas plasmáticas se diferencian estructuralmente de las membranas de los dominios Bacteria y Eukaria porque están organizadas en una monocapa, presentan variaciones en el tamaño de las cadenas de carbono alifáticas, en los enlaces carbono-carbono y tienen componentes estructurales únicos, tales como tetraéteres de glicerol-dialquil-glicerol (GDGT) y arqueoles. Desafortunadamente, se le da poca importancia al dominio de Archaea en los cursos que se ofrecen a los estudiantes de Ciencias Biológicas. El objetivo de este trabajo fue recopilar información sobre la membrana de Archaea y complementar el repertorio literario actual utilizado para la enseñanza de módulos relacionados con la membrana plasmática en las disciplinas de Biología Celular y Molecular en Brasil.Em Biologia, a célula é considerada a unidade funcional dos seres vivos. Seus constituintes são fundamentalmente material genético, citoplasma e membrana plasmática. Estes três componentes estruturais exercem, dentre outros papéis biológicos, reprodução e manutenção celular, suporte à atividade metabólica e manutenção da barreira físico-química. Portanto, para a compreensão da fisiologia e estrutura celular, é imperativo o estudo dos processos em que esses componentes estão envolvidos, que nos cursos de ensino superior são abordados principalmente nas disciplinas de Biologia Celular e Molecular. Grande parte do conteúdo dessas disciplinas é dedicada ao estudo da estrutura, composição e evolução da membrana plasmática, muitas vezes referida de forma genérica como membrana celular. Em alguns clados em Archaea, um dos três domínios da vida, a membrana celular promove características fisiológicas únicas que permitem o sucesso evolutivo de tais grupos e sua sobrevivência em ambientes inóspitos para outras formas de vida. Nestas células, as membranas plasmáticas diferem estruturalmente das membranas dos domínios Bacteria e Eukaria por se organizarem em monocamada, apresentarem variações no tamanho das cadeias carbônicas alifáticas, nas ligações carbono-carbono e possuírem componentes estruturais exclusivos, como por exemplo os Glicerol-dialkil-glicerol-tetraéteres (GDGTs) e os Arqueóis. Infelizmente, pouca importância é dada ao domínio Archaea nos cursos que são oferecidos a alunos de Ciências Biológicas. O objetivo deste trabalho foi compilar informações sobre a membrana de Archaea e suplementar o atual repertório literário usado para o ensino dos módulos referentes à membrana plasmática nas disciplinas de Biologia Celular e Molecular no Brasil

Protein Profile and oxidative metabolism of lambs experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E

Para avaliar a influência da suplementação com selênio e vitamina E sobre o perfil proteico e metabolismo oxidativo de cordeiros infectados experimentalmente pelo Haemonchus contortus, trinta cordeiros fêmeas foram distribuídos em quatro grupos: G1 (n=10): animais infectados; G2 (n=10): infectados e suplementados; G3 (n=5): controle; e G4 (n=5): não infectados e suplementados. Os grupos 1 e 2 receberam 500 larvas de H. contortus (L3), via oral, por um período de 20 dias, com intervalo de dois dias entre as doses. A suplementação nos grupos 2 e 4 foi realizada no dia zero, com 0,1mg kg-1 de Selenito de sódio (1,67%) e com 2.000UI de vitamina E por via intramuscular (IM). Somente a vitamina E foi reaplicada no dia 30. As coletas de sangue para determinação do perfil proteico (proteína total, albumina, alfa, beta e gamaglobulina) e metabolismo oxidativo (espécies reativas ao ácido tiobarbitúrico-TBARS e a enzima glutationa peroxidase (GSPX) foram realizadas nos dias zero, 20, 30, 45, 60 e 80. OPG foi quantificado nos dias 0, 20 ,45 e 80. Em relação aos valores de proteínas totais, albumina, betaglobulina e gamaglobulina, as principais diferenças foram observadas quando os grupos parasitados foram comparados com o grupo somente suplementado; e este manteve valores mais elevados. Conclui-se que não há influência da suplementação com selênio e vitamina E no perfil proteico e metabolismo oxidativo quando os cordeiros se encontram severamente parasitados por H.contortus.The objective of the present study was to describe the influence of supplementation with selenium and vitamin E on the protein and oxidative profiles of lambs experimentally infected with Haemonchus contortus. Thirty female lambs were divided into four groups as follows: G1 (n=10): infected animals; G2 (n=10): infected and supplemented; G3 (n=5): control; G4 (n=5): non-infected and supplemented. Groups 1 and 2 received 500 H. contortus larvae (L3) orally for a period of 20 days, with 2-day intervals between doses. Supplementation in groups 2 and 4 was performed on day zero by injecting 0.1mg kg-1 of sodium selenite solution (1.67%) and 2,000IU vitamin E through the intramuscular (IM) route. Vitamin E alone was injected once again on day thirty. The blood samples to determine the protein profile (total protein, albumin, alpha, beta and gamma) and oxidative metabolism (species reactive to thiobarbituric acid and glutathione peroxidase (GSPX) were performed on days zero, 20, 30, 45, 60 and 80. The OPG was quantified on days 0, 20, 45 and 80. Regarding the values of total proteins, albumin, beta and gamma globulins, the main differences were observed when the parasitized groups were compared to the supplemented, non-infected group, the latter exhibiting higher values. It is concluded that there is no influence of supplementation with vitamin E and selenium in the protein profile and oxidative metabolism when the lambs are severely parasitized with H. contortus

Avaliação da usabilidade de um material educativo digital interativo: um estudo transversal

Objective: to verify the usability of the Automatic Pocket Guide (GBA) as an anatomical review method for medical students at a private institution in the city of Salvador. Methodology: the study was carried out with students of the Bahiana School of Medicine and Public Health (EBMSP) of the 1st and 2nd year through the application of a virtual form made available by email and cross-platform instant messaging application. The adapted Self Directed Learning Readiness Scale (SDLRS) was used to outline the students' study profile, the System Sustainability Scale (SUS) and the Post Study System Usability Questionnaire (PSSUQ) were used to measure the usability of the GBA. The survey took place from October do December 2021.  Results: 103 participants responded to the virtual form, 68.9% were female and with an average age between 18 and 20 years (72.9%), who had an active study profile and familiarity with resources fingerprints. The SUS showed that the GBA was considered an OK application - SUS Score of 68.37 - and, in the PSSUQ, the general satisfaction with the system obtained an average of 2.61 (±0.09), representing a positive usability of the GBA. Also in PSSUQ, information quality (2.51 ±0.13) and interface quality (2.52 ±0.15) obtained strong results. Conclusion: Auto Pocket Guide is a tool with good overall usability. From this, further studies are needed to assess its impact on the performance and content retention of medical students.Objetivo: verificar a usabilidade do Guia de Bolso Automático (GBA) como método de revisão anatômica para alunos do curso de medicina de uma instituição privada da cidade de Salvador. Metodologia: o estudo foi realizado com alunos da Escola Bahiana de Medicina e Saúde Pública (EBMSP) do 1º e 2º ano através da aplicação de um formulário virtual disponibilizado por e-mail e aplicativo multiplataforma de mensagens instantâneas. A escala Self Directed Learning Readiness Scale (SDLRS) adaptada foi utilizada para traçar o perfil de estudo dos estudantes, a System Usability Scale (SUS) e o Post Study System Usability Questionnaire (PSSUQ) foram mensuraram a usabilidade do GBA. A pesquisa ocorreu no período de outubro a dezembro de 2021. Resultados: 103 participantes responderam o formulário virtual, sendo 68,9% do sexo feminino e com idade média entre 18 e 20 anos (72,9%), que possuíam um perfil de estudo ativo e familiaridade com recursos digitais. A SUS evidenciou que o GBA foi considerado um aplicativo OK - Score SUS de 68,37 - e, na PSSUQ, a satisfação geral com o sistema obteve média de 2,61 (±0,09), representando uma usabilidade positiva do GBA. Ainda na PSSUQ, a qualidade da informação (2,51 ±0,13) e a qualidade da interface (2,52 ±0,15) obtiveram resultados satisfatórios. Conclusão: o Guia de Bolso Automático é uma ferramenta com boa usabilidade geral. A partir disso, mais estudos são necessários para avaliar seu impacto no desempenho e retenção de conteúdo dos estudantes de medicina

Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK.

BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca

Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK

Background A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. Methods This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. Findings Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0–75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4–97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8–80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3–4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. Interpretation ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials

The National Student Survey: validation in Portuguese medical students

The UK National Student Survey (NSS) is a sound and widely used instrument for assessing students’ academic experiences. We aimed to translate the NSS for Portuguese students and to validate the instrument in a sample of medical undergraduates. The research team translated and adapted the NSS for Portuguese students (NSS-P). The survey was administered on an online platform to 1,256 final-year students at eight Portuguese medical schools. A total of 329 medical students (69.9% female) replied to the NSS-P, a response rate of 26.2%. Confirmatory factor analysis showed that the original six-factor structure had an adequate fit to the data. Adequate internal consistency was observed for all the subscales. Medium to large correlations were found among all the subscale scores and between the subscale scores and the students’ overall satisfaction. Multiple regression showed that the scores on the Teaching, Organization and Management and Personal Development subscales significantly predicted the students’ overall satisfaction. Approximately 64% of the students reported being satisfied with the quality of their courses. Significant differences among the medical schools in their NSS-P scores were found. The NSS-P is a valid and reliable measure for assessing medical students’ perceptions of academic quality

Investigation of SARS-CoV-2 infection in dogs and cats of humans diagnosed with COVID-19 in Rio de Janeiro, Brazil.

BackgroundInfection by SARS-CoV-2 in domestic animals has been related to close contact with humans diagnosed with COVID-19. Objectives: To assess the exposure, infection, and persistence by SARS-CoV-2 of dogs and cats living in the same households of humans that tested positive for SARS-CoV-2, and to investigate clinical and laboratory alterations associated with animal infection.MethodsAnimals living with COVID-19 patients were longitudinally followed and had nasopharyngeal/oropharyngeal and rectal swabs collected and tested for SARS-CoV-2. Additionally, blood samples were collected for laboratory analysis, and plaque reduction neutralization test (PRNT90) to investigate specific SARS-CoV-2 antibodies.ResultsBetween May and October 2020, 39 pets (29 dogs and 10 cats) of 21 patients were investigated. Nine dogs (31%) and four cats (40%) from 10 (47.6%) households were infected with or seropositive for SARS-CoV-2. Animals tested positive from 11 to 51 days after the human index COVID-19 case onset of symptoms. Three dogs tested positive twice within 14, 30, and 31 days apart. SARS-CoV-2 neutralizing antibodies were detected in one dog (3.4%) and two cats (20%). In this study, six out of thirteen animals either infected with or seropositive for SARS-CoV-2 have developed mild but reversible signs of the disease. Using logistic regression analysis, neutering, and sharing bed with the ill owner were associated with pet infection.ConclusionsThe presence and persistence of SARS-CoV-2 infection have been identified in dogs and cats from households with human COVID-19 cases in Rio de Janeiro, Brazil. People with COVID-19 should avoid close contact with their pets during the time of their illness

A Potential SARS-CoV-2 Variant of Interest (VOI) Harboring Mutation E484K in the Spike Protein Was Identified within Lineage B.1.1.33 Circulating in Brazil

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic in Brazil was dominated by two lineages designated as B.1.1.28 and B.1.1.33. The two SARS-CoV-2 variants harboring mutations at the receptor-binding domain of the Spike (S) protein, designated as lineages P.1 and P.2, evolved from lineage B.1.1.28 and are rapidly spreading in Brazil. Lineage P.1 is considered a Variant of Concern (VOC) because of the presence of multiple mutations in the S protein (including K417T, E484K, N501Y), while lineage P.2 only harbors mutation S:E484K and is considered a Variant of Interest (VOI). On the other hand, epidemiologically relevant B.1.1.33 deriving lineages have not been described so far. Here we report the identification of a new SARS-CoV-2 VOI within lineage B.1.1.33 that also harbors mutation S:E484K and was detected in Brazil between November 2020 and February 2021. This VOI displayed four non-synonymous lineage-defining mutations (NSP3:A1711V, NSP6:F36L, S:E484K, and NS7b:E33A) and was designated as lineage N.9. The VOI N.9 probably emerged in August 2020 and has spread across different Brazilian states from the Southeast, South, North, and Northeast regions