Via acessória médio-septal: papel do eletrocardiograma como preditor da localizaçao no estudo eletrofisiológico

INTRODUÇAO: A aplicaçao do eletrocardiograma de 12 derivaçoes para localizar a via acessória na síndrome de Wolff-Parkinson-White é útil para o planejamento terapêutico invasivo. Este estudo teve como objetivo definir as características eletrocardiográficas preditoras da localizaçao médio-septal e relatar os resultados obtidos em pacientes submetidos a ablaçao por radiofrequência. MÉTODO: Estudo retrospectivo e longitudinal, analisando características eletrocardiográficas pré e pós-ablaçao e informaçoes referentes aos resultados após o procedimento. RESULTADOS: Integraram o estudo 91 pacientes, 11 dos quais apresentaram via acessória com localizaçao médio-septal. As características eletrocardiográficas preditoras da via médio-septal foram: padrao de bloqueio de ramo esquerdo em V1 (odds ratio = 50; P = 0,008), onda delta positiva em D3 (odds ratio = 20,8; P = 0,04) e complexo QRS nao positivo em V2 (odds ratio = 15,2; P = 0,003). Nessa sequência, os achados foram combinados na forma de algoritmo para predizer a localizaçao da via médio-septal, com acurácia de 92,3%, sensibilidade de 90,4%, especificidade de 92,5% e valor preditivo negativo de 87,9%. O sucesso foi menor na via médio-septal que nas demais vias (45,5% e 87,5%, respectivamente; P = 0,001). Com relaçao às complicaçoes, nao houve diferença estatística de induçao de bloqueio atrioventricular entre a via médio-septal e as demais vias. CONCLUSAO: Os achados eletrocardiográficos foram capazes de predizer a via médio-septal com boa acurácia. Houve mais insucesso na via médio-septal e taxas similares de complicaçoes nas outras vias

Via acessória médio-septal: papel do eletrocardiograma como preditor da localizaçao no estudo eletrofisiológico

INTRODUÇAO: A aplicaçao do eletrocardiograma de 12 derivaçoes para localizar a via acessória na síndrome de Wolff-Parkinson-White é útil para o planejamento terapêutico invasivo. Este estudo teve como objetivo definir as características eletrocardiográficas preditoras da localizaçao médio-septal e relatar os resultados obtidos em pacientes submetidos a ablaçao por radiofrequência. MÉTODO: Estudo retrospectivo e longitudinal, analisando características eletrocardiográficas pré e pós-ablaçao e informaçoes referentes aos resultados após o procedimento. RESULTADOS: Integraram o estudo 91 pacientes, 11 dos quais apresentaram via acessória com localizaçao médio-septal. As características eletrocardiográficas preditoras da via médio-septal foram: padrao de bloqueio de ramo esquerdo em V1 (odds ratio = 50; P = 0,008), onda delta positiva em D3 (odds ratio = 20,8; P = 0,04) e complexo QRS nao positivo em V2 (odds ratio = 15,2; P = 0,003). Nessa sequência, os achados foram combinados na forma de algoritmo para predizer a localizaçao da via médio-septal, com acurácia de 92,3%, sensibilidade de 90,4%, especificidade de 92,5% e valor preditivo negativo de 87,9%. O sucesso foi menor na via médio-septal que nas demais vias (45,5% e 87,5%, respectivamente; P = 0,001). Com relaçao às complicaçoes, nao houve diferença estatística de induçao de bloqueio atrioventricular entre a via médio-septal e as demais vias. CONCLUSAO: Os achados eletrocardiográficos foram capazes de predizer a via médio-septal com boa acurácia. Houve mais insucesso na via médio-septal e taxas similares de complicaçoes nas outras vias

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

Definition and use of the variable "race" by medical students in Salvador, Brazil

CONTEXT AND OBJECTIVE: The lack of a clear definition for human "race" and the importance of this topic in medical practice continue to create doubt among scholars. Here, we evaluate the use of the variable "race" by medical students in Salvador, Brazil. DESIGN AND SETTING: Cross-sectional study at a Brazilian federal public university. METHODS: 221 randomly selected subjects were included. A semi-structured questionnaire was used for data collection. The results were expressed as means and standard deviations of the mean, proportions and frequencies. The χ2 (chi-square) test was used for the statistical calculations. RESULTS: Approximately half of the students (45.4%) used the racial group variable in their studies on clinical practice. Of these, 86.8% considered it to be relevant information in the medical records and 92.7%, important for diagnostic reasoning; 95.9% believed that it influenced the cause, expression and prevalence of diseases; 94.9% affirmed that it contributed towards estimating the risk of diseases; 80.5% thought that the therapeutic response to medications might be influenced by racial characteristics; 41.9% considered that its inclusion in research was always recommendable; and 20.3% thought it was indispensable. The main phenotypic characteristics used for racial classification were: skin color (93.2%), hair type (45.7%), nose shape (33.9%) and lip thickness (30.3%). CONCLUSIONS: Despite the importance of different racial groups in medical practice, the majority of the professionals do not use or know how to classify them. It is necessary to add to and/or expand the discussion of racial and ethnic categories in medical practice and research

Influence of core-finishing intervals on tensile strength of cast posts-and-cores luted with zinc phosphate cement

The core finishing of cast posts-and-cores after luting is routine in dental practice. However, the effects of the vibrations produced by the rotary cutting instruments over the luting cements are not well-documented. This study evaluated the influence of the time intervals that elapsed between the cementation and the core-finishing procedures on the tensile strength of cast posts-and-cores luted with zinc phosphate cement. Forty-eight bovine incisor roots were selected, endodontically treated, and divided into four groups (n = 12): GA, control (without finishing); GB, GC, and GD, subjected to finishing at 20 minutes, 60 minutes, and 24 hours after cementation, respectively. Root canals were molded, and the resin patterns were cast in copper-aluminum alloy. Cast posts-and-cores were luted with zinc phosphate cement, and the core-finishing procedures were applied according to the groups. The tensile tests were performed at a crosshead speed of 0.5 mm/min for all groups, 24 hours after the core-finishing procedures. The data were subjected to one-way analysis of variance (ANOVA) and Tukey's test (α = 0.05). No significant differences were observed in the tensile strengths between the control and experimental groups, regardless of the time interval that elapsed between the luting and finishing steps. Within the limitations of the present study, it was demonstrated that the core-finishing procedures and time intervals that elapsed after luting did not appear to affect the retention of cast posts-and-cores when zinc phosphate cement was used

Diffuse alveolar damage patterns reflect the immunological and molecular heterogeneity in fatal COVID-19

Background: Severe COVID-19 lung disease exhibits a high degree of spatial and temporal heterogeneity, with different histological features coexisting within a single individual. It is important to capture the disease complexity to support patient management and treatment strategies. We provide spatially decoded analyses on the immunopathology of diffuse alveolar damage (DAD) patterns and factors that modulate immune and structural changes in fatal COVID-19. Methods: We spatially quantified the immune and structural cells in exudative, intermediate, and advanced DAD through multiplex immunohistochemistry in autopsy lung tissue of 18 COVID-19 patients. Cytokine profiling, viral, bacteria, and fungi detection, and transcriptome analyses were performed. Findings: Spatial DAD progression was associated with expansion of immune cells, macrophages, CD8+ T cells, fibroblasts, and (lymph)angiogenesis. Viral load correlated positively with exudative DAD and negatively with disease/hospital length. In all cases, enteric bacteria were isolated, and Candida parapsilosis in eight cases. Cytokines correlated mainly with macrophages and CD8+T cells. Pro-coagulation and acute repair were enriched pathways in exudative DAD whereas intermediate/advanced DAD had a molecular profile of elevated humoral and innate immune responses and extracellular matrix production. Interpretation: Unraveling the spatial and molecular immunopathology of COVID-19 cases exposes the responses to SARS-CoV-2-induced exudative DAD and subsequent immune-modulatory and remodeling changes in proliferative/advanced DAD that occur side-by-side together with secondary infections in the lungs. These complex features have important implications for disease management and the development of novel treatments. Funding: CNPq, Bill and Melinda Gates Foundation, HC-Convida, FAPESP, Regeneron Pharmaceuticals, and the Swedish Heart & Lung Foundation