RESUMO
A multiband (MB) echo-planar imaging (EPI) sequence is compared to a multiband multiecho (MBME) EPI protocol to investigate differences in sensitivity for task functional magnetic resonance imaging (fMRI) at 3 T. Multiecho sampling improves sensitivity in areas where single-echo-EPI suffers from dropouts. However, It requires in-plane acceleration to reduce the echo train length, limiting the slice acceleration factor and the temporal and spatial resolution Data were acquired for both protocols in two sessions 24 h apart using an adapted color-word interference Stroop task. Besides protocol comparison statistically, we performed test-retest reliability across sessions for different protocols and denoising methods. We evaluated the sensitivity of two different echo-combination strategies for MBME-EPI. We examined the performance of three different data denoising approaches: "Standard," "AROMA," and "FIX" for MB and MBME, and assessed whether a specific method is preferable. We consider using an appropriate autoregressive model order within the general linear model framework to correct TR differences between the protocols. The comparison between protocols and denoising methods showed at group level significantly higher mean z-scores and the number of active voxels for MBME in the motor, subcortical and medial frontal cortices. When comparing different echo combinations, our results suggest that a contrast-to-noise ratio weighted echo combination improves sensitivity in MBME compared to simple echo-summation. This study indicates that MBME can be a preferred protocol in task fMRI at spatial resolution (≥2 mm), primarily in medial prefrontal and subcortical areas.
Assuntos
Imagem Ecoplanar , Imageamento por Ressonância Magnética , Humanos , Imagem Ecoplanar/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Reprodutibilidade dos Testes , Processamento de Imagem Assistida por Computador/métodos , Mapeamento Encefálico/métodosRESUMO
BACKGROUND: Thrombotic events, such as venous thromboembolism (VTE) are a major health complication linked to rheumatoid arthritis (RA). We performed a meta-analysis to evaluate the risk of VTE, including deep vein thrombosis (DVT) and pulmonary embolism (PE), in adults with RA compared to the general population. METHODS: MEDLINE and EMBASE databases were searched from inception to April 2022 to identify publications meeting the following criteria: (1) prospective and retrospective original data from cohort or case-control studies; (2) pre-specified RA definition; (3) clearly defined VTE outcomes; (4) reported risk estimate and 95% confidence intervals (95% CIs); (5) at least sex- and age-matched to comparison group; and (6) English language. Of 372 studies screened, 14 were included (602,760 RA patients, 123,076 VTE events) and their quality was assessed by an adaptation of the STROBE quality scoring scale. RESULTS: The pooled risk ratios of VTE, DVT and PE in patients with RA were 1.57 (95% CI 1.41-1.76), 1.58 (95% CI 1.26-1.97) and 1.57 (95% CI 1.30-1.88), respectively. The I2 value of 92%, 94% and 92% for VTE, DVT and PE analyses, suggesting considerable heterogeneity. There were no significant differences in risk estimates among the five subgroup analyses: quality score (P = 0.35, I2 = 0%); sex (P = 0.31, I2 = 1.7%); study year (P = 0.81, I2 = 0%); population source (P = 0.35, I2 = 0%); study design (P = 0.62, I2 = 0%). CONCLUSIONS: Results show that patients with RA are at a higher risk of VTE, DVT and PE compared to the general population.
RESUMO
BACKGROUND: Vaccination against the novel coronavirus is one of the most effective strategies for combating the global Coronavirus disease (COVID-19) pandemic. However, vaccine hesitancy has emerged as a major obstacle in several regions of the world, including Africa. The objective of this rapid review was to summarize the literature on COVID-19 vaccine hesitancy in Africa. METHODS: We searched Scopus, Web of Science, African Index Medicus, and OVID Medline for studies published from January 1, 2020, to March 8, 2022, examining acceptance or hesitancy towards the COVID-19 vaccine in Africa. Study characteristics and reasons for COVID-19 vaccine acceptance were extracted from the included articles. RESULTS: A total of 71 articles met the eligibility criteria and were included in the review. Majority (n = 25, 35%) of the studies were conducted in Ethiopia. Studies conducted in Botswana, Cameroun, Cote D'Ivoire, DR Congo, Ghana, Kenya, Morocco, Mozambique, Nigeria, Somalia, South Africa, Sudan, Togo, Uganda, Zambia, Zimbabwe were also included in the review. The vaccine acceptance rate ranged from 6.9 to 97.9%. The major reasons for vaccine hesitancy were concerns with vaccine safety and side effects, lack of trust for pharmaceutical industries and misinformation or conflicting information from the media. Factors associated with positive attitudes towards the vaccine included being male, having a higher level of education, and fear of contracting the virus. CONCLUSIONS: Our review demonstrated the contextualized and multifaceted reasons inhibiting or encouraging vaccine uptake in African countries. This evidence is key to operationalizing interventions based on facts as opposed to assumptions. Our paper provided important considerations for addressing the challenge of COVID-19 vaccine hesitancy and blunting the impact of the pandemic in Africa.
Assuntos
COVID-19 , Transtornos Urinários , Vacinas , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Feminino , Humanos , Masculino , Nigéria , Vacinação , Hesitação VacinalRESUMO
INTRODUCTION: Cases of the novel coronavirus disease (COVID-19) continue to spread around the world even one year after the declaration of a global pandemic. Those with weakened immune systems, due to immunosuppressive medications or disease, may be at higher risk of COVID-19. This includes individuals with autoimmune diseases, cancer, transplants, and dialysis patients. Assessing the risk and outcomes of COVID-19 in this population has been challenging. While administrative databases provide data with minimal selection and recall bias, clinical and behavioral data is lacking. To address this, we are collecting self-reported survey data from a randomly selected subsample with and without COVID-19, which will be linked to administrative health data, to better quantify the risk of COVID-19 infection associated with immunosuppression. METHODS AND ANALYSIS: Using administrative and laboratory data from British Columbia (BC), Canada, we established a population-based case-control study of all individuals who tested positive for SARS-CoV-2. Each case was matched to 40 randomly selected individuals from two control groups: individuals who tested negative for SARS-CoV-2 (i.e., negative controls) and untested individuals from the general population (i.e., untested controls). We will contact 1000 individuals from each group to complete a survey co-designed with patient partners. A conditional logistic regression model will adjust for potential confounders and effect modifiers. We will examine the odds of COVID-19 infection according to immunosuppressive medication or disease type. To adjust for relevant confounders and effect modifiers not available in administrative data, the survey will include questions on behavioural variables that influence probability of being tested, acquiring COVID-19, and experiencing severe outcomes. ETHICS AND DISSEMINATION: This study has received approval from the University of British Columbia Clinical Research Ethics Board [H20-01914]. Findings will be disseminated through scientific conferences, open access peer-reviewed journals, COVID-19 research repositories and dissemination channels used by our patient partners.