47 results on '"Paiva JM"'
Search Results
2. Automated myocardial segmentation in native t1-mapping cardiovascular magnetic resonance images based on machine learning: a validation study in the UK biobank"s covid-19 subset
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Rauseo, E, primary, Lockhart, L, additional, Paiva, JM, additional, Fung, K, additional, Khanji, MY, additional, Raisi-Estabragh, Z, additional, Amir-Khalili, A, additional, and Petersen, SE, additional
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- 2021
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3. Improving the generalizability of convolutional neural network-based segmentation on CMR images
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Chen, C, Bai, W, Davies, RH, Bhuva, AN, Manisty, C, Moon, JC, Aung, N, Lee, AM, Sanghvi, MM, Fung, K, Paiva, JM, Petersen, SE, Lukaschuk, E, Piechnik, SK, Neubauer, S, and Rueckert, D
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eess.IV ,cs.CV - Abstract
Convolutional neural network (CNN) based segmentation methods provide an efficient and automated way for clinicians to assess the structure and function of the heart in cardiac MR images. While CNNs can generally perform the segmentation tasks with high accuracy when training and test images come from the same domain (e.g. same scanner or site), their performance often degrades dramatically on images from different scanners or clinical sites. We propose a simple yet effective way for improving the network generalization ability by carefully designing data normalization and augmentation strategies to accommodate common scenarios in multi-site, multi-scanner clinical imaging data sets. We demonstrate that a neural network trained on a single-site single-scanner dataset from the UK Biobank can be successfully applied to segmenting cardiac MR images across different sites and different scanners without substantial loss of accuracy. Specifically, the method was trained on a large set of 3,975 subjects from the UK Biobank. It was then directly tested on 600 different subjects from the UK Biobank for intra-domain testing and two other sets for cross-domain testing: the ACDC dataset (100 subjects, 1 site, 2 scanners) and the BSCMR-AS dataset (599 subjects, 6 sites, 9 scanners). The proposed method produces promising segmentation results on the UK Biobank test set which are comparable to previously reported values in the literature, while also performing well on cross-domain test sets, achieving a mean Dice metric of 0.90 for the left ventricle, 0.81 for the myocardium and 0.82 for the right ventricle on the ACDC dataset; and 0.89 for the left ventricle, 0.83 for the myocardium on the BSCMR-AS dataset. The proposed method offers a potential solution to improve CNN-based model generalizability for the cross-scanner and cross-site cardiac MR image segmentation task.
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- 2019
4. Association between ambient air pollution and cardiac morpho-functional phenotypes: insights from the UK Biobank Population Imaging Study
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Aung, N, Sanghvi, MM, Zemrak, F, Lee, AM, Cooper, JA, Paiva, JM, Thomson, RJ, Fung, K, Khanji, MY, Lukaschuk, E, Carapella, V, Kim, YJ, Munroe, PB, Piechnik, SK, Neubauer, S, and Petersen, SE
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Background: Exposure to ambient air pollution is strongly associated with increased cardiovascular morbidity and mortality. Little is known about the influence of air pollutants on cardiac structure and function. We aim to investigate the relationship between chronic past exposure to traffic-related pollutants and the cardiac chamber volume, ejection fraction, and left ventricular remodeling patterns after accounting for potential confounders. Methods: Exposure to ambient air pollutants including particulate matter and nitrogen dioxide was estimated from the Land Use Regression models for the years between 2005 and 2010. Cardiac parameters were measured from cardiovascular magnetic resonance imaging studies of 3920 individuals free from pre-existing cardiovascular disease in the UK Biobank population study. The median (interquartile range) duration between the year of exposure estimate and the imaging visit was 5.2 (0.6) years. We fitted multivariable linear regression models to investigate the relationship between cardiac parameters and traffic-related pollutants after adjusting for various confounders. Results: The studied cohort was 62±7 years old, and 46% were men. In fully adjusted models, particulate matter with an aerodynamic diameter Conclusions: In a large asymptomatic population with no prevalent cardiovascular disease, higher past exposure to particulate matter with an aerodynamic diameter
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- 2019
5. Automated localization and quality control of the aorta in cine CMR can significantly accelerate processing of the UK Biobank population data
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Biasiolli, L, Hann, E, Lukaschuk, E, Carapella, V, Paiva, JM, Aung, N, Rayner, JJ, Werys, K, Fung, K, Puchta, H, Sanghvi, MM, Moon, NO, Thomson, RJ, Thomas, KE, Robson, MD, Grau, V, Petersen, SE, Neubauer, S, and Piechnik, SK
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Science ,Medicine - Abstract
Introduction Aortic distensibility can be calculated using semi-automated methods to segment the aortic lumen on cine CMR (Cardiovascular Magnetic Resonance) images. However, these methods require visual quality control and manual localization of the region of interest (ROI) of ascending (AA) and proximal descending (PDA) aorta, which limit the analysis in large-scale population-based studies. Using 5100 scans from UK Biobank, this study sought to develop and validate a fully automated method to 1) detect and locate the ROIs of AA and PDA, and 2) provide a quality control mechanism. Methods The automated AA and PDA detection-localization algorithm followed these steps: 1) foreground segmentation; 2) detection of candidate ROIs by Circular Hough Transform (CHT); 3) spatial, histogram and shape feature extraction for candidate ROIs; 4) AA and PDA detection using Random Forest (RF); 5) quality control based on RF detection probability. To provide the ground truth, overall image quality (IQ = 0–3 from poor to good) and aortic locations were visually assessed by 13 observers. The automated algorithm was trained on 1200 scans and Dice Similarity Coefficient (DSC) was used to calculate the agreement between ground truth and automatically detected ROIs. Results The automated algorithm was tested on 3900 scans. Detection accuracy was 99.4% for AA and 99.8% for PDA. Aorta localization showed excellent agreement with the ground truth, with DSC ≥ 0.9 in 94.8% of AA (DSC = 0.97 ± 0.04) and 99.5% of PDA cases (DSC = 0.98 ± 0.03). AA×PDA detection probabilities could discriminate scans with IQ ≥ 1 from those severely corrupted by artefacts (AUC = 90.6%). If scans with detection probability < 0.75 were excluded (350 scans), the algorithm was able to correctly detect and localize AA and PDA in all the remaining 3550 scans (100% accuracy). Conclusion The proposed method for automated AA and PDA localization was extremely accurate and the automatically derived detection probabilities provided a robust mechanism to detect low quality scans for further human review. Applying the proposed localization and quality control techniques promises at least a ten-fold reduction in human involvement without sacrificing any accuracy.
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- 2019
6. The impact of menopausal hormone therapy (MHT) on cardiac structure and function: Insights from the UK Biobank imaging enhancement study
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Sanghvi, MM, Aung, N, Cooper, JA, Paiva, JM, Lee, AM, Zemrak, F, Fung, K, Thomson, RJ, Lukaschuk, E, Carapella, V, Kim, YJ, Harvey, NC, Piechnik, SK, Neubauer, S, and Petersen, SE
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Aging ,Physiology ,Blood Pressure ,Comorbidity ,Cardiovascular Medicine ,Vascular Medicine ,Diagnostic Radiology ,Endocrinology ,Risk Factors ,Medicine and Health Sciences ,Cardiovascular Imaging ,Organic Compounds ,Radiology and Imaging ,Middle Aged ,Magnetic Resonance Imaging ,Stroke ,Postmenopause ,Chemistry ,Neurology ,Cardiovascular Diseases ,Physical Sciences ,Medicine ,Female ,Menopause ,Research Article ,Endocrine Disorders ,Imaging Techniques ,Hormone Replacement Therapy ,Science ,Cerebrovascular Diseases ,Heart Ventricles ,Cardiology ,Research and Analysis Methods ,Diagnostic Medicine ,Diabetes Mellitus ,Humans ,Heart Atria ,Endocrine Physiology ,Organic Chemistry ,Chemical Compounds ,Biology and Life Sciences ,Stroke Volume ,United Kingdom ,Cross-Sectional Studies ,Alcohols ,Metabolic Disorders ,Ejection Fraction ,Follow-Up Studies - Abstract
Background The effect of menopausal hormone therapy (MHT)±previously known as hormone replacement therapy±on cardiovascular health remains unclear and controversial. This cross-sectional study examined the impact of MHT on left ventricular (LV) and left atrial (LA) structure and function, alterations in which are markers of subclinical cardiovascular disease, in a population-based cohort. Methods Post-menopausal women who had never used MHT and those who had used MHT ≥3 years participating in the UK Biobank who had undergone cardiovascular magnetic resonance (CMR) imaging and free of known cardiovascular disease were included. Multivariable linear regression was performed to examine the relationship between cardiac parameters and MHT use ≥3 years. To explore whether MHT use on each of the cardiac outcomes differed by age, multivariable regression models were constructed with a crossproduct of age and MHT fitted as an interaction term. Results Of 1604 post-menopausal women, 513 (32%) had used MHT ≥3 years. In the MHT cohort, median age at menopause was 50 (IQR: 45±52) and median duration of MHT was 8 years. In the non-MHT cohort, median age at menopause was 51 (IQR: 48±53). MHT use was associated with significantly lower LV end-diastolic volume (122.8 ml vs 119.8 ml, effect size = -2.4%, 95% CI: -4.2% to -0.5%; p = 0.013) and LA maximal volume (60.2 ml vs 57.5 ml, effect size = -4.5%, 95% CI: -7.8% to -1.0%; p = 0.012). There was no significant difference in LV mass. MHT use significantly modified the effect between age and CMR parameters; MHT users had greater decrements in LV end-diastolic volume, LV end-systolic volume and LA maximal volume with advancing age. Conclusions MHT use was not associated with adverse, subclinical changes in cardiac structure and function. Indeed, significantly smaller LV and LA chamber volumes were observed which have been linked to favourable cardiovascular outcomes. These findings represent a novel approach to examining MHT's effect on the cardiovascular system.
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- 2018
7. Automated cardiovascular magnetic resonance image analysis with fully convolutional networks
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Bai, W, Sinclair, M, Tarroni, G, Oktay, O, Rajchl, M, Vaillant, G, Lee, AM, Aung, N, Lukaschuk, E, Sanghvi, MM, Zemrak, F, Fung, K, Paiva, JM, Carapella, V, Kim, YJ, Suzuki, H, Kainz, B, Matthews, PM, Petersen, SE, Piechnik, SK, Neubauer, S, Glocker, B, Rueckert, D, Engineering & Physical Science Research Council (E, Engineering & Physical Science Research Council (EPSRC), UK DRI Ltd, Medical Research Council (MRC), and Imperial College London
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FOS: Computer and information sciences ,Male ,lcsh:Diseases of the circulatory (Cardiovascular) system ,LEFT-VENTRICLE ,Cardiac & Cardiovascular Systems ,Databases, Factual ,Heart Diseases ,Computer Vision and Pattern Recognition (cs.CV) ,Computer Science - Computer Vision and Pattern Recognition ,SEGMENTATION ,Magnetic Resonance Imaging, Cine ,DIAGNOSIS ,Ventricular Function, Left ,Automation ,Deep Learning ,Predictive Value of Tests ,Machine learning ,Image Interpretation, Computer-Assisted ,LEVEL SET ,Humans ,Fully convolutional networks ,1102 Cardiorespiratory Medicine and Haematology ,cs.CV ,080104 Computer Vision ,Aged ,Observer Variation ,Science & Technology ,T1 ,Research ,Radiology, Nuclear Medicine & Medical Imaging ,Reproducibility of Results ,Stroke Volume ,Middle Aged ,Myocardial Contraction ,Nuclear Medicine & Medical Imaging ,CMR image analysis ,lcsh:RC666-701 ,Cardiovascular System & Cardiology ,cardiovascular system ,Ventricular Function, Right ,HEART-FAILURE ,Female ,08 Information and Computing Sciences ,Neural Networks, Computer ,Life Sciences & Biomedicine ,RC - Abstract
Cardiovascular magnetic resonance (CMR) imaging is a standard imaging modality for assessing cardiovascular diseases (CVDs), the leading cause of death globally. CMR enables accurate quantification of the cardiac chamber volume, ejection fraction and myocardial mass, providing information for diagnosis and monitoring of CVDs. However, for years, clinicians have been relying on manual approaches for CMR image analysis, which is time consuming and prone to subjective errors. It is a major clinical challenge to automatically derive quantitative and clinically relevant information from CMR images. Deep neural networks have shown a great potential in image pattern recognition and segmentation for a variety of tasks. Here we demonstrate an automated analysis method for CMR images, which is based on a fully convolutional network (FCN). The network is trained and evaluated on a large-scale dataset from the UK Biobank, consisting of 4,875 subjects with 93,500 pixelwise annotated images. The performance of the method has been evaluated using a number of technical metrics, including the Dice metric, mean contour distance and Hausdorff distance, as well as clinically relevant measures, including left ventricle (LV) end-diastolic volume (LVEDV) and end-systolic volume (LVESV), LV mass (LVM); right ventricle (RV) end-diastolic volume (RVEDV) and end-systolic volume (RVESV). By combining FCN with a large-scale annotated dataset, the proposed automated method achieves a high performance on par with human experts in segmenting the LV and RV on short-axis CMR images and the left atrium (LA) and right atrium (RA) on long-axis CMR images., Comment: Accepted for publication by Journal of Cardiovascular Magnetic Resonance
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- 2018
8. Variation in lung function and alterations in cardiac structure and function-Analysis of the UK Biobank cardiovascular magnetic resonance imaging substudy
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Thomson, RJ, Aung, N, Sanghvi, MM, Paiva, JM, Lee, AM, Zemrak, F, Fung, K, Pfeffer, PE, Mackay, AJ, McKeever, TM, Lukaschuk, E, Carapella, V, Kim, YJ, Bolton, CE, Piechnik, SK, Neubauer, S, and Petersen, SE
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Male ,Pulmonology ,Physiology ,Science ,Cerebrovascular Diseases ,Cardiology ,Pulmonary Function ,Blood Pressure ,Linear Regression Analysis ,Research and Analysis Methods ,Vascular Medicine ,Mathematical and Statistical Techniques ,Heart Rate ,Forced Expiratory Volume ,Medicine and Health Sciences ,Respiratory Analysis ,Humans ,Respiratory Physiology ,Prospective Studies ,Statistical Methods ,Lung ,Biological Specimen Banks ,Myocardium ,Biology and Life Sciences ,Heart ,Stroke Volume ,Middle Aged ,Magnetic Resonance Imaging ,United Kingdom ,Respiratory Function Tests ,Stroke ,Bioassays and Physiological Analysis ,Neurology ,Spirometry ,Physical Sciences ,Linear Models ,Medicine ,Regression Analysis ,Female ,Mathematics ,Statistics (Mathematics) ,Research Article ,Ejection Fraction - Abstract
Background Reduced lung function is common and associated with increased cardiovascular morbidity and mortality, even in asymptomatic individuals without diagnosed respiratory disease. Previous studies have identified relationships between lung function and cardiovascular structure in individuals with pulmonary disease, but the relationships in those free from diagnosed cardiorespiratory disease have not been fully explored. Methods UK Biobank is a prospective cohort study of community participants in the United Kingdom. Individuals self-reported demographics and co-morbidities, and a subset underwent cardiovascular magnetic resonance (CMR) imaging and spirometry. CMR images were analysed to derive ventricular volumes and mass. The relationships between CMR-derived measures and spirometry and age were modelled with multivariable linear regression, taking account of the effects of possible confounders. Results Data were available for 4,975 individuals, and after exclusion of those with pre-existing cardiorespiratory disease and unacceptable spirometry, 1,406 were included in the analyses. In fully-adjusted multivariable linear models lower FEV1 and FVC were associated with smaller left ventricular end-diastolic (−5.21ml per standard deviation (SD) change in FEV1, −5.69ml per SD change in FVC), end-systolic (−2.34ml, −2.56ml) and stroke volumes (−2.85ml, −3.11ml); right ventricular end-diastolic (−5.62ml, −5.84ml), end-systolic (−2.47ml, −2.46ml) and stroke volumes (−3.13ml, −3.36ml); and with lower left ventricular mass (−2.29g, −2.46g). Changes of comparable magnitude and direction were observed per decade increase in age. Conclusions This study shows that reduced FEV1 and FVC are associated with smaller ventricular volumes and reduced ventricular mass. The changes seen per standard deviation change in FEV1 and FVC are comparable to one decade of ageing.
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- 2018
9. Prospective association between handgrip strength and cardiac structure and function in UK adults
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Beyer, SE, Sanghvi, MM, Aung, N, Hosking, A, Cooper, JA, Paiva, JM, Lee, AM, Fung, K, Lukaschuk, E, Carapella, V, Mittleman, MA, Brage, S, Piechnik, SK, Neubauer, S, Petersen, SE, and Abete, P
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cardiovascular system - Abstract
Background Handgrip strength, a measure of muscular fitness, is associated with cardiovascular (CV) events and CV mortality but its association with cardiac structure and function is unknown. The goal of this study was to determine if handgrip strength is associated with changes in cardiac structure and function in UK adults. Methods and results Left ventricular (LV) ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), mass (M), and mass-to-volume ratio (MVR) were measured in a sample of 4,654 participants of the UK Biobank Study 6.3 ± 1 years after baseline using cardiovascular magnetic resonance (CMR). Handgrip strength was measured at baseline and at the imaging follow-up examination. We determined the association between handgrip strength at baseline as well as its change over time and each of the cardiac outcome parameters. After adjustment, higher level of handgrip strength at baseline was associated with higher LVEDV (difference per SD increase in handgrip strength: 1.3ml, 95% CI 0.1±2.4; p = 0.034), higher LVSV (1.0ml, 0.3±1.8; p = 0.006), lower LVM (-1.0g, -1.8 ±-0.3; p = 0.007), and lower LVMVR (-0.013g/ml, -0.018 ±-0.007; p Conclusions Better handgrip strength was associated with cardiac structure and function in a pattern indicative of less cardiac hypertrophy and remodeling. These characteristics are known to be associated with a lower risk of cardiovascular events.
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- 2018
10. Human-level CMR image analysis with deep fully convolutional networks
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Bai, W, Sinclair, M, Tarroni, G, Oktay, O, Rajchl, M, Vaillant, G, Lee, AM, Aung, N, Lukaschuk, E, Sanghvi, MM, Zemrak, F, Fung, K, Paiva, JM, Carapella, V, Kim, YJ, Suzuki, H, Kainz, B, Matthews, PM, Petersen, SE, Piechnik, SK, Neubauer, S, Glocker, B, and Rueckert, D
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cardiovascular system ,cardiovascular diseases ,cs.CV - Abstract
Cardiovascular magnetic resonance (CMR) imaging is a standard imaging modality for assessing cardiovascular diseases (CVDs), the leading cause of death globally. CMR enables accurate quantification of the cardiac chamber volume, ejection fraction and myocardial mass, providing a wealth of information for sensitive and specific diagnosis and monitoring of CVDs. However, for years, clinicians have been relying on manual approaches for CMR image analysis, which is time consuming and prone to subjective errors. It is a major clinical challenge to automatically derive quantitative and clinically relevant information from CMR images. Deep neural networks have shown a great potential in image pattern recognition and segmentation for a variety of tasks. Here we demonstrate an automated analysis method for CMR images, which is based on a fully convolutional network (FCN). The network is trained and evaluated on a dataset of unprecedented size, consisting of 4,875 subjects with 93,500 pixelwise annotated images, which is by far the largest annotated CMR dataset. By combining FCN with a large-scale annotated dataset, we show for the first time that an automated method achieves a performance on par with human experts in analysing CMR images and deriving clinical measures. We anticipate this to be a starting point for automated and comprehensive CMR analysis with human-level performance, facilitated by machine learning. It is an important advance on the pathway towards computer-assisted CVD assessment.
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- 2017
11. The impact of cardiovascular risk factors on cardiac structure and function: Insights from the UK Biobank imaging enhancement study
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Petersen, SE, Sanghvi, MM, Aung, N, Cooper, JA, Paiva, JM, Zemrak, F, Fung, K, Lukaschuk, E, Lee, AM, Carapella, V, Kim, YJ, Piechnik, SK, Neubauer, S, and Fukumoto, Y
- Abstract
Aims The UK Biobank is a large-scale population-based study utilising cardiovascular magnetic resonance (CMR) to generate measurements of atrial and ventricular structure and function. This study aimed to quantify the association between modifiable cardiovascular risk factors and cardiac morphology and function in individuals without known cardiovascular disease. Methods Age, sex, ethnicity (non-modifiable) and systolic blood pressure, diastolic blood pressure, smoking status, exercise, body mass index (BMI), high cholesterol, diabetes, alcohol intake (modifiable) were considered important cardiovascular risk factors. Multivariable regression models were built to ascertain the association of risk factors on left ventricular (LV), right ventricular (RV), left atrial (LA) and right atrial (RA) CMR parameters. Results 4,651 participants were included in the analysis. All modifiable risk factors had significant effects on differing atrial and ventricular parameters. BMI was the modifiable risk factor most consistently associated with subclinical changes to CMR parameters, particularly in relation to higher LV mass (+8.3% per SD [4.3 kg/m2], 95% CI: 7.6 to 8.9%), LV (EDV: +4.8% per SD, 95% CI: 4.2 to 5.4%); ESV: +4.4% per SD, 95% CI: 3.5 to 5.3%), RV (EDV: +5.3% per SD, 95% CI: 4.7 to 5.9%; ESV: +5.4% per SD, 95% CI: 4.5 to 6.4%) and LA maximal (+8.6% per SD, 95% CI: 7.4 to 9.7%) volumes. Increases in SBP were associated with higher LV mass (+6.8% per SD, 95% CI: 5.9 to 7.7%), LV (EDV: +4.5% per SD, 95% CI: 3.6 to 5.4%; ESV: +2.0% per SD, 95% CI: 0.8 to 3.3%) volumes. The presence of diabetes or high cholesterol resulted in smaller volumes and lower ejection fractions. Conclusions Modifiable risk factors are associated with subclinical alterations in structure and function in all four cardiac chambers. BMI and systolic blood pressure are the most important modifiable risk factors affecting CMR parameters known to be linked to adverse outcomes.
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- 2017
12. Are There Differences Among Evidence-Based Psychotherapies for Treating Different DSM-5 PTSD Symptom Clusters? A Systematic Review and Meta-analysis of Controlled Clinical Trials.
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Melani MS, Paiva JM, Mendlowicz MV, Vilete L, Luz MP, Ventura PR, Passos RBF, and Berger W
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- Humans, Controlled Clinical Trials as Topic, Stress Disorders, Post-Traumatic therapy, Stress Disorders, Post-Traumatic classification, Stress Disorders, Post-Traumatic diagnosis, Psychotherapy methods, Diagnostic and Statistical Manual of Mental Disorders
- Abstract
Abstract: Posttraumatic stress disorder (PTSD) is a heterogeneous disease defined by four Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) symptom clusters: reexperiencing, avoidance, negative alterations in cognitions and mood, and hyperarousal. There are effective evidence-based psychotherapies (EBPs) for PTSD. However, given the variety of PTSD clinical presentations, we conducted the first meta-analysis investigating whether DSM-5 PTSD symptom clusters show different responses to EBPs. We systematically reviewed the literature for controlled clinical trials in five databases, performed a meta-analysis, and evaluated the methodological quality of the studies. We screened 633 studies and included seven. Three showed high risk, two showed some concerns, and one showed a low risk of bias. The symptom clusters do not seem to respond differently to EBPs (SMD cluster B: -0.40; 95% confidence interval [CI], -0.87 to 0.08; cluster C: -0.49; 95% CI, -0.90 to -0.08; cluster D: -0.44; 95% CI, -0.94 to 0.05; cluster E: -0.54; 95% CI, -1.07 to -0.0), even when analyzed by the therapeutic focuses. The findings dovetail nicely with the network theory of PTSD symptom, as although it is a heterogeneous disorder, the EBPs seem to promote a kind of cascade of symptom improvement., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2024
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13. The efficacy of internet-delivered cognitive-behavioral therapy for posttraumatic stress disorder according to the mean age of patients: a systematic review and meta-analysis.
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Paiva JM, Dos Santos Melani M, Marques ESN, Arcosy CV, Coutinho ESF, Ventura P, and Berger W
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- Humans, Age Factors, Internet-Based Intervention, Adult, Internet, Randomized Controlled Trials as Topic, Stress Disorders, Post-Traumatic therapy, Cognitive Behavioral Therapy methods
- Abstract
Internet-delivered cognitive-behavioral therapy (I-CBT) is effective in treating post-traumatic stress disorder (PTSD) symptoms, offering enhanced accessibility and cost-effectiveness. However, it's important to note that these technologies may not be suitable for all age groups. Therefore, we conducted a systematic review and meta-analysis to determine if the effectiveness of I-CBT in treating PTSD varies based on the patients' mean age. We conducted a systematic review of the literature, focusing on randomized controlled trials (RCTs) in the ISI Web of Science, PubMed/MEDLINE, and PsycINFO databases. Following this, we performed a meta-analysis and evaluated the risk of bias using the Cochrane risk of bias quality assessment tool. In this study, we examined patient-related factors (civil or military status, age, and gender), clinical characteristics (baseline PTSD severity and type of trauma), and treatment characteristics (type of intervention, synchronous or asynchronous delivery, and the number of sessions) as independent variables. The dependent variable was the reduction in mean PTSD symptoms. Five RCTs out of 1,552 screened studies were included in this review, all of which showed some level of concern regarding potential bias. Our meta-analysis indicates that I-CBT is equally effective regardless of patients' mean age. Since all RCTs included only provide the mean age of the patients, further randomized controlled trials should address the effectiveness of I-CBT among different age groups.
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- 2024
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14. Stuck in a Moment: Tonic Immobility Predicts Poor Quality of Life in Treated PTSD Patients.
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Kalaf J, Coutinho ESF, Mendlowicz M, Portella CM, Berger W, Luz MP, Volchan E, Ventura PR, Júdice MN, Blanco SAF, Paiva JM, and Figueira I
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- Humans, Quality of Life, Immobility Response, Tonic, Cross-Sectional Studies, Dissociative Disorders therapy, Dissociative Disorders psychology, Surveys and Questionnaires, Stress Disorders, Post-Traumatic therapy, Stress Disorders, Post-Traumatic psychology
- Abstract
Background: Posttraumatic stress disorder (PTSD) is a prevalent and disabling multisystem disorder, with significant physical and psychiatric morbidity and poor quality of life (QOL). Although peritraumatic reactions - tonic immobility and dissociation - are established predictors of PTSD severity and development, there is a dearth of investigation assessing the impact of peritraumatic reactions on QOL of PTSD patients. Quality of life has become increasingly important in health care and research as a reliable outcome measure. It comprises psychological, physical, social and environmental domains, providing important information about the impact of diseases on patient's life. This study aims to investigate the impact of peritraumatic tonic immobility and peritraumatic dissociation on QOL of PTSD civilian outpatients., Subjects and Methods: It is a cross-sectional study of 50 victims of urban violence with current PTSD, recruited in a specialized outpatient clinic. Instruments used were: Structured Clinical Interview IV, Peritraumatic Dissociative Experiences Questionnaire, Tonic Immobility Scale and WHOQOL-BREF (psychological, physical, social and environmental domains). Linear regression models were fitted to evaluate the impact of peritraumatic reactions - tonic immobility and dissociation - on WHOQOL-BREF scores. We controlled for sex as potential confounding., Results: The severity of peritraumatic tonic immobility negatively impacted on psychological and environment domains of quality of life. For each additional point on the Tonic Immobility Scale, there was a decreased of 0.8 points on the scores of these domains of WHOQOL-BREF. Neither the peritraumatic reactions showed effects on physical nor social domains. Possible limitations of this study include cross-sectional design, relatively small sample size of tertiary center outpatients and recall bias., Conclusions: Peritraumatic tonic immobility is related to poor quality of life, adding new insights about the relationship between this immobility reaction and PTSD.
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- 2022
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15. A Systematic Quality Scoring Analysis to Assess Automated Cardiovascular Magnetic Resonance Segmentation Algorithms.
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Rauseo E, Omer M, Amir-Khalili A, Sojoudi A, Le TT, Cook SA, Hausenloy DJ, Ang B, Toh DF, Bryant J, Chin CWL, Paiva JM, Fung K, Cooper J, Khanji MY, Aung N, and Petersen SE
- Abstract
Background: The quantitative measures used to assess the performance of automated methods often do not reflect the clinical acceptability of contouring. A quality-based assessment of automated cardiac magnetic resonance (CMR) segmentation more relevant to clinical practice is therefore needed., Objective: We propose a new method for assessing the quality of machine learning (ML) outputs. We evaluate the clinical utility of the proposed method as it is employed to systematically analyse the quality of an automated contouring algorithm., Methods: A dataset of short-axis (SAX) cine CMR images from a clinically heterogeneous population ( n = 217) were manually contoured by a team of experienced investigators. On the same images we derived automated contours using a ML algorithm. A contour quality scoring application randomly presented manual and automated contours to four blinded clinicians, who were asked to assign a quality score from a predefined rubric. Firstly, we analyzed the distribution of quality scores between the two contouring methods across all clinicians. Secondly, we analyzed the interobserver reliability between the raters. Finally, we examined whether there was a variation in scores based on the type of contour, SAX slice level, and underlying disease., Results: The overall distribution of scores between the two methods was significantly different, with automated contours scoring better than the manual (OR (95% CI) = 1.17 (1.07-1.28), p = 0.001; n = 9401). There was substantial scoring agreement between raters for each contouring method independently, albeit it was significantly better for automated segmentation (automated: AC2 = 0.940, 95% CI, 0.937-0.943 vs manual: AC2 = 0.934, 95% CI, 0.931-0.937; p = 0.006). Next, the analysis of quality scores based on different factors was performed. Our approach helped identify trends patterns of lower segmentation quality as observed for left ventricle epicardial and basal contours with both methods. Similarly, significant differences in quality between the two methods were also found in dilated cardiomyopathy and hypertension., Conclusions: Our results confirm the ability of our systematic scoring analysis to determine the clinical acceptability of automated contours. This approach focused on the contours' clinical utility could ultimately improve clinicians' confidence in artificial intelligence and its acceptability in the clinical workflow., Competing Interests: SEP provides consultancy to and owns stock of Cardiovascular Imaging Inc, Calgary, Alberta, Canada. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Rauseo, Omer, Amir-Khalili, Sojoudi, Le, Cook, Hausenloy, Ang, Toh, Bryant, Chin, Paiva, Fung, Cooper, Khanji, Aung and Petersen.)
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- 2022
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16. Responses of benthic diatoms to waters affected by post-fire contamination.
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Vidal T, Pereira JL, Moreira F, Silva J, Santos M, Campos I, Benoliel MJ, Paiva JM, Cardoso VV, Barreto R, Neto AQ, Gonçalves FJM, and Abrantes N
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- Ecosystem, Environmental Monitoring, Rivers, Diatoms, Water Pollutants, Chemical analysis, Water Pollutants, Chemical toxicity, Wildfires
- Abstract
Wildfire effects go beyond direct impact in terrestrial ecosystems. Specifically, the periphytic communities of aquatic ecosystems standing within and downstream the burnt areas are relevant ecological receptors of post-fire runoff contamination. Nevertheless, the off-site impacts of wildfires in these communities are limitedly studied so far. The present study aimed to assess the effects of river water contaminated with ash-loaded runoff in the growth benthic diatom Navicula libonensis (Schoeman 1970). Four surface water samples were collected approximately one year after the wildfire for laboratory testing with the diatom: one was collected from a site upstream the burnt area, within the Unhais river (UU); three were collected from sites standing within the burnt area, one in the Unhais river (UB) and two in the Zêzere river (Z1 and Z2), reflecting different hydrological regimes. N. libonensis was proven able to discriminate among river sites affected and unaffected by wildfire runoff, reflecting, in general, the expected trends considering the physico-chemical characterization of the water samples. The water samples from the sites standing within the burnt area inhibited the biomass yield and growth rate of the tested diatom, ranking the samples regarding toxicity as follows: Z1 > UB > Z2 > UU. However, UB rather than Z1 presented the highest contaminant burden, namely metal elements, and some were found above widely accepted safety benchmarks (polycyclic aromatic hydrocarbons were not detected). This inconsistency can be linked to unknown interactions among metals within each water sample, to differential nutrient enrichment of samples, as well as hydrological factors. Overall, our results suggest that monospecific laboratory assays with sensitive diatoms can be valuable as cost-effective screening tools to prioritize sites affected by wildfires runoff requiring in-depth monitoring of negative effects in benthic producer communities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)
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- 2021
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17. Sex-specific associations between alcohol consumption, cardiac morphology, and function as assessed by magnetic resonance imaging: insights form the UK Biobank Population Study.
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Simon J, Fung K, Kolossváry M, Sanghvi MM, Aung N, Paiva JM, Lukaschuk E, Carapella V, Merkely B, Bittencourt MS, Karády J, Lee AM, Piechnik SK, Neubauer S, Maurovich-Horvat P, and Petersen SE
- Subjects
- Alcohol Drinking epidemiology, Female, Heart Atria diagnostic imaging, Humans, Magnetic Resonance Spectroscopy, Male, Middle Aged, Stroke Volume, United Kingdom epidemiology, Ventricular Function, Left, Biological Specimen Banks, Magnetic Resonance Imaging
- Abstract
Aims: Data regarding the effects of regular alcohol consumption on cardiac anatomy and function are scarce. Therefore, we sought to determine the relationship between regular alcohol intake and cardiac structure and function as evaluated with cardiac magnetic resonance imaging., Methods and Results: Participants of the UK Biobank who underwent cardiac magnetic resonance were enrolled in our analysis. Data regarding regular alcohol consumption were obtained from questionnaires filled in by the study participants. Exclusion criteria were poor image quality, missing, or incongruent data regarding alcohol drinking habits, prior drinking, presence of heart failure or angina, and prior myocardial infarction or stroke. Overall, 4335 participants (61.5 ± 7.5 years, 47.6% male) were analysed. We used multivariate linear regression models adjusted for age, ethnicity, body mass index, smoking, hypertension, diabetes mellitus, physical activity, cholesterol level, and Townsend deprivation index to examine the relationship between regular alcohol intake and cardiac structure and function. In men, alcohol intake was independently associated with marginally increased left ventricular end-diastolic volume [β = 0.14; 95% confidence interval (CI) = 0.05-0.24; P = 0.004], left ventricular stroke volume (β = 0.08; 95% CI = 0.03-0.14; P = 0.005), and right ventricular stroke volume (β = 0.08; 95% CI = 0.02-0.13; P = 0.006). In women, alcohol consumption was associated with increased left atrium volume (β = 0.14; 95% CI = 0.04-0.23; P = 0.006)., Conclusion: Alcohol consumption is independently associated with a marginal increase in left and right ventricular volumes in men, but not in women, whereas alcohol intake showed an association with increased left atrium volume in women. Our results suggest that there is only minimal relationship between regular alcohol consumption and cardiac morphology and function in an asymptomatic middle-aged population., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)
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- 2021
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18. Subclinical Changes in Cardiac Functional Parameters as Determined by Cardiovascular Magnetic Resonance (CMR) Imaging in Sleep Apnea and Snoring: Findings from UK Biobank.
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Curta A, Hetterich H, Schinner R, Lee AM, Sommer W, Aung N, Sanghvi MM, Fung K, Lukaschuk E, Cooper JA, Paiva JM, Carapella V, Neubauer S, Piechnik SK, and Petersen SE
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- Female, Humans, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Male, Prospective Studies, Stroke Volume, United Kingdom, Ventricular Function, Left, Ventricular Function, Right, Biological Specimen Banks, Snoring diagnostic imaging
- Abstract
Background and Objectives: Obstructive sleep apnea (OSA) is a common disorder with an increased risk for left ventricular and right ventricular dysfunction. Most studies to date have examined populations with manifest cardiovascular disease using echocardiography to analyze ventricular dysfunction with little or no reference to ventricular volumes or myocardial mass. Our aim was to explore these parameters with cardiac MRI. We hypothesized that there would be stepwise increase in left ventricular mass and right ventricular volumes from the unaffected, to the snoring and the OSA group. Materials and Methods: We analyzed cardiac MRI data from 4978 UK Biobank participants free from cardiovascular disease. Participants were allocated into three cohorts: with OSA, with self-reported snoring and without OSA or snoring ( n = 118, 1886 and 2477). We analyzed cardiac parameters from balanced cine-SSFP sequences and indexed them to body surface area. Results: Patients with OSA were mostly males (47.3% vs. 79.7%; p < 0.001) with higher body mass index (25.7 ± 4.0 vs. 31.3 ± 5.3 kg/m²; p < 0.001) and higher blood pressure (135 ± 18 vs. 140 ± 17 mmHg; p = 0.012) compared to individuals without OSA or snoring. Regression analysis showed a significant effect for OSA in left ventricular end-diastolic index (LVEDVI) (β = -4.9 ± 2.4 mL/m²; p = 0.040) and right ventricular end-diastolic index (RVEDVI) (β = -6.2 ± 2.6 mL/m²; p = 0.016) in females and for right ventricular ejection fraction (RVEF) (β = 1.7 ± 0.8%; p = 0.031) in males. A significant effect was discovered in snoring females for left ventricular mass index (LVMI) (β = 3.5 ± 0.9 g/m²; p < 0.001) and in males for left ventricular ejection fraction (LVEF) (β = 1.0 ± 0.3%; p = 0.001) and RVEF (β = 1.2 ± 0.3%; p < 0.001). Conclusion: Our study suggests that OSA is highly underdiagnosed and that it is an evolving process with gender specific progression. Females with OSA show significantly lower ventricular volumes while males with snoring show increased ejection fractions which may be an early sign of hypertrophy. Separate prospective studies are needed to further explore the direction of causality.
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- 2021
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19. Adverse cardiovascular magnetic resonance phenotypes are associated with greater likelihood of incident coronavirus disease 2019: findings from the UK Biobank.
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Raisi-Estabragh Z, McCracken C, Cooper J, Fung K, Paiva JM, Khanji MY, Rauseo E, Biasiolli L, Raman B, Piechnik SK, Neubauer S, Munroe PB, Harvey NC, and Petersen SE
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- Aged, Aged, 80 and over, Biological Specimen Banks, COVID-19 Testing, Female, Humans, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Male, Phenotype, Predictive Value of Tests, SARS-CoV-2, Stroke Volume, United Kingdom epidemiology, Ventricular Function, Left, COVID-19
- Abstract
Background: Coronavirus disease 2019 (COVID-19) disproportionately affects older people. Observational studies suggest indolent cardiovascular involvement after recovery from acute COVID-19. However, these findings may reflect pre-existing cardiac phenotypes., Aims: We tested the association of baseline cardiovascular magnetic resonance (CMR) phenotypes with incident COVID-19., Methods: We studied UK Biobank participants with CMR imaging and COVID-19 testing. We considered left and right ventricular (LV, RV) volumes, ejection fractions, and stroke volumes, LV mass, LV strain, native T1, aortic distensibility, and arterial stiffness index. COVID-19 test results were obtained from Public Health England. Co-morbidities were ascertained from self-report and hospital episode statistics (HES). Critical care admission and death were from HES and death register records. We investigated the association of each cardiovascular measure with COVID-19 test result in multivariable logistic regression models adjusting for age, sex, ethnicity, deprivation, body mass index, smoking, diabetes, hypertension, high cholesterol, and prior myocardial infarction., Results: We studied 310 participants (n = 70 positive). Median age was 63.8 [57.5, 72.1] years; 51.0% (n = 158) were male. 78.7% (n = 244) were tested in hospital, 3.5% (n = 11) required critical care admission, and 6.1% (n = 19) died. In fully adjusted models, smaller LV/RV end-diastolic volumes, smaller LV stroke volume, and poorer global longitudinal strain were associated with significantly higher odds of COVID-19 positivity., Discussion: We demonstrate association of pre-existing adverse CMR phenotypes with greater odds of COVID-19 positivity independent of classical cardiovascular risk factors., Conclusions: Observational reports of cardiovascular involvement after COVID-19 may, at least partly, reflect pre-existing cardiac status rather than COVID-19 induced alterations.
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- 2021
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20. Poor Bone Quality is Associated With Greater Arterial Stiffness: Insights From the UK Biobank.
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Raisi-Estabragh Z, Biasiolli L, Cooper J, Aung N, Fung K, Paiva JM, Sanghvi MM, Thomson RJ, Curtis E, Paccou J, Rayner JJ, Werys K, Puchta H, Thomas KE, Lee AM, Piechnik SK, Neubauer S, Munroe PB, Cooper C, Petersen SE, and Harvey NC
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- Biological Specimen Banks, Female, Humans, Male, Risk Factors, Ultrasonography, United Kingdom epidemiology, Vascular Stiffness
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Osteoporosis and ischemic heart disease (IHD) represent important public health problems. Existing research suggests an association between the two conditions beyond that attributable to shared risk factors, with a potentially causal relationship. In this study, we tested the association of bone speed of sound (SOS) from quantitative heel ultrasound with (i) measures of arterial compliance from cardiovascular magnetic resonance (aortic distensibility [AD]); (ii) finger photoplethysmography (arterial stiffness index [ASI]); and (iii) incident myocardial infarction and IHD mortality in the UK Biobank cohort. We considered the potential mediating effect of a range of blood biomarkers and cardiometabolic morbidities and evaluated differential relationships by sex, menopause status, smoking, diabetes, and obesity. Furthermore, we considered whether associations with arterial compliance explained association of SOS with ischemic cardiovascular outcomes. Higher SOS was associated with lower arterial compliance by both ASI and AD for both men and women. The relationship was most consistent with ASI, likely relating to larger sample size available for this variable (n = 159,542 versus n = 18,229). There was no clear evidence of differential relationship by menopause, smoking, diabetes, or body mass index (BMI). Blood biomarkers appeared important in mediating the association for both men and women, but with different directions of effect and did not fully explain the observed effects. In fully adjusted models, higher SOS was associated with significantly lower IHD mortality in men, but less robustly in women. The association of SOS with ASI did not explain this observation. In conclusion, our findings support a positive association between bone and vascular health with consistent patterns of association in men and women. The underlying mechanisms are complex and appear to vary by sex. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)., (© 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).)
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- 2021
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21. Cardiovascular magnetic resonance reference values of mitral and tricuspid annular dimensions: the UK Biobank cohort.
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Ricci F, Aung N, Gallina S, Zemrak F, Fung K, Bisaccia G, Paiva JM, Khanji MY, Mantini C, Palermi S, Lee AM, Piechnik SK, Neubauer S, and Petersen SE
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- Age Factors, Aged, Cross-Sectional Studies, Female, Healthy Volunteers, Humans, Male, Middle Aged, Observer Variation, Predictive Value of Tests, Reference Values, Reproducibility of Results, Sex Factors, United Kingdom, White People, Magnetic Resonance Imaging, Cine, Mitral Valve diagnostic imaging, Tricuspid Valve diagnostic imaging
- Abstract
Background: Mitral valve (MV) and tricuspid valve (TV) apparatus geometry are essential to define mechanisms and etiologies of regurgitation and to inform surgical or transcatheter interventions. Given the increasing use of cardiovascular magnetic resonance (CMR) for the evaluation of valvular heart disease, we aimed to establish CMR-derived age- and sex-specific reference values for mitral annular (MA) and tricuspid annular (TA) dimensions and tethering indices derived from truly healthy Caucasian adults., Methods: 5065 consecutive UK Biobank participants underwent CMR using cine balanced steady-state free precession imaging at 1.5 T. Participants with non-Caucasian ethnicity, prevalent cardiovascular disease and other conditions known to affect cardiac chamber size and function were excluded. Absolute and indexed reference ranges for MA and TA diameters and tethering indices were stratified by gender and age (45-54, 55-64, 65-74 years)., Results: Overall, 721 (14.2%) truly healthy participants aged 45-74 years (54% women) formed the reference cohort. Absolute MA and TA diameters, MV tenting length and MV tenting area, were significantly larger in men. Mean ± standard deviation (SD) end-diastolic and end-systolic MA diameters in the 3-chamber view (anteroposterior diameter) were 2.9 ± 0.4 cm (1.5 ± 0.2 cm/m
2 ) and 3.3 ± 0.4 cm (1.7 ± 0.2 cm/m2 ) in men, and 2.6 ± 0.4 cm (1.6 ± 0.2 cm/m2 ) and 3.0 ± 0.4 cm (1.8 ± 0.2 cm/m2 ) in women, respectively. Mean ± SD end-diastolic and end-systolic TA diameters in the 4-chamber view were 3.2 ± 0.5 cm (1.6 ± 0.3 cm/m2 ) and 3.2 ± 0.5 cm (1.7 ± 0.3 cm/m2 ) in men, and 2.9 ± 0.4 cm (1.7 ± 0.2 cm/m2 ) and 2.8 ± 0.4 cm (1.7 ± 0.3 cm/m2 ) in women, respectively. With advancing age, end-diastolic TA diameter became larger and posterior MV leaflet angle smaller in both sexes. Reproducibility of measurements was good to excellent with an inter-rater intraclass correlation coefficient (ICC) between 0.92 and 0.98 and an intra-rater ICC between 0.90 and 0.97., Conclusions: We described age- and sex-specific reference ranges of MA and TA dimensions and tethering indices in the largest validated healthy Caucasian population. Reference ranges presented in this study may help to improve the distinction between normal and pathological states, prompting the identification of subjects that may benefit from advanced cardiac imaging for annular sizing and planning of valvular interventions.- Published
- 2020
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22. Absence of definitive scientific evidence that benzodiazepines could hinder the efficacy of exposure-based interventions in adults with anxiety or posttraumatic stress disorders: A systematic review of randomized clinical trials.
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Melani MS, Paiva JM, Silva MC, Mendlowicz MV, Figueira I, Marques-Portella C, Luz MP, Ventura PR, and Berger W
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- Adult, Anxiety, Anxiety Disorders drug therapy, Humans, Randomized Controlled Trials as Topic, Benzodiazepines therapeutic use, Stress Disorders, Post-Traumatic drug therapy
- Abstract
Background and Objectives: Exposure-based interventions (EBIs) are the first-line treatment for anxiety disorders and posttraumatic stress disorder. Although common, the association between EBIs and benzodiazepines is controversial. Therefore, we systematically reviewed the literature to evaluate if benzodiazepines could undermine the efficacy of EBIs in treating these disorders., Methods: We conducted a systematic review aiming for randomized clinical trials (RCTs) in ISI Web of Science, Scopus, PubMed/MEDLINE, and PsycINFO databases. We scrutinized the reference list of selected papers and other systematic reviews. Finally, we evaluated the methodological quality and the scientific evidence of the studies., Results: We screened 1,529 studies and included 12 RCTs in this review (all showing some concerns or high risk of bias). Benzodiazepines did not impact the efficacy of EBIs in nine studies at posttreatment, improved efficacy in two, and reduced it in one. In the follow-up, benzodiazepines (after its discontinuation) did not impact the efficacy in six studies and reduced it in five. The scientific level of evidence achieved was B for both phases., Conclusions: Until now there is no definitive evidence that benzodiazepines could hinder the EBIs' efficacy for treating posttraumatic stress disorder and anxiety disorders., (© 2020 Wiley Periodicals LLC.)
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- 2020
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23. Improving the Generalizability of Convolutional Neural Network-Based Segmentation on CMR Images.
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Chen C, Bai W, Davies RH, Bhuva AN, Manisty CH, Augusto JB, Moon JC, Aung N, Lee AM, Sanghvi MM, Fung K, Paiva JM, Petersen SE, Lukaschuk E, Piechnik SK, Neubauer S, and Rueckert D
- Abstract
Background: Convolutional neural network (CNN) based segmentation methods provide an efficient and automated way for clinicians to assess the structure and function of the heart in cardiac MR images. While CNNs can generally perform the segmentation tasks with high accuracy when training and test images come from the same domain (e.g., same scanner or site), their performance often degrades dramatically on images from different scanners or clinical sites. Methods: We propose a simple yet effective way for improving the network generalization ability by carefully designing data normalization and augmentation strategies to accommodate common scenarios in multi-site, multi-scanner clinical imaging data sets. We demonstrate that a neural network trained on a single-site single-scanner dataset from the UK Biobank can be successfully applied to segmenting cardiac MR images across different sites and different scanners without substantial loss of accuracy. Specifically, the method was trained on a large set of 3,975 subjects from the UK Biobank. It was then directly tested on 600 different subjects from the UK Biobank for intra-domain testing and two other sets for cross-domain testing: the ACDC dataset (100 subjects, 1 site, 2 scanners) and the BSCMR-AS dataset (599 subjects, 6 sites, 9 scanners). Results: The proposed method produces promising segmentation results on the UK Biobank test set which are comparable to previously reported values in the literature, while also performing well on cross-domain test sets, achieving a mean Dice metric of 0.90 for the left ventricle, 0.81 for the myocardium, and 0.82 for the right ventricle on the ACDC dataset; and 0.89 for the left ventricle, 0.83 for the myocardium on the BSCMR-AS dataset. Conclusions: The proposed method offers a potential solution to improve CNN-based model generalizability for the cross-scanner and cross-site cardiac MR image segmentation task., (Copyright © 2020 Chen, Bai, Davies, Bhuva, Manisty, Augusto, Moon, Aung, Lee, Sanghvi, Fung, Paiva, Petersen, Lukaschuk, Piechnik, Neubauer and Rueckert.)
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- 2020
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24. Association Between Recreational Cannabis Use and Cardiac Structure and Function.
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Khanji MY, Jensen MT, Kenawy AA, Raisi-Estabragh Z, Paiva JM, Aung N, Fung K, Lukaschuk E, Zemrak F, Lee AM, Barutcu A, Maclean E, Cooper J, Piechnik SK, Neubauer S, and Petersen SE
- Subjects
- Aged, Female, Heart Diseases diagnostic imaging, Heart Diseases physiopathology, Humans, Magnetic Resonance Imaging, Cine, Male, Middle Aged, Risk Factors, Heart Diseases etiology, Marijuana Abuse complications, Marijuana Smoking adverse effects, Myocardial Contraction, Ventricular Function, Left
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- 2020
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25. Does self-reported pregnancy loss identify women at risk of an adverse cardiovascular phenotype in later life? Insights from UK Biobank.
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Elmahi E, Sanghvi MM, Jones A, Aye CYL, Lewandowski AJ, Aung N, Cooper JA, Paiva JM, Lukaschuk E, Piechnik SK, Neubauer S, Petersen SE, and Leeson P
- Subjects
- Adult, Aged, Cardiovascular Diseases diagnostic imaging, Carotid Intima-Media Thickness, Confounding Factors, Epidemiologic, Female, Humans, Magnetic Resonance Imaging, Middle Aged, Pregnancy, Risk Factors, United Kingdom epidemiology, Abortion, Spontaneous epidemiology, Biological Specimen Banks, Cardiovascular Diseases epidemiology, Cardiovascular Diseases etiology, Self Report
- Abstract
Introduction: Cardiovascular disease (CVD) is more common in women who have had pregnancy complications such as spontaneous pregnancy loss. We used cross-sectional data from the UK Biobank Imaging Enhancement Study to determine whether pregnancy loss is associated with cardiac or vascular remodelling in later life, which might contribute to this increased risk., Methods: Pregnancy history was reported by women participating in UK Biobank between 2006 and 2010 at age 40-69 years using a self-completed touch-screen questionnaire. Associations between self-reported spontaneous pregnancy loss and cardiovascular measures, collected in women who participated in the Imaging Enhancement Study up to the end of 2015, were examined. Cardiac structure and function were assessed by magnetic resonance (CMR) steady-state free precession imaging at 1.5 Tesla. Carotid intima-media thickness (CIMT) measurements were taken for both common carotid arteries using a CardioHealth Station. Statistical associations with CMR and carotid measures were adjusted for age, BMI and other cardiovascular risk factors., Results: Data were available on 2660 women of whom 111 were excluded because of pre-existing cardiovascular disease and 30 had no pregnancy information available. Of the remaining 2519, 446 were nulligravid and 2073 had a history of pregnancies, of whom 622 reported at least one pregnancy loss (92% miscarriages and 8% stillbirths) and 1451 reported no pregnancy loss. No significant differences in any cardiac or carotid parameters were evident in women who reported pregnancy loss compared to other groups (Table 1)., Conclusion: Women who self-report pregnancy loss do not have significant differences in cardiac structure, cardiac function, or carotid structure in later life to explain their increased cardiovascular risk. This suggests any cardiovascular risks associated with pregnancy loss operate through other disease mechanisms. Alternatively, other characteristics of pregnancy loss, which we were not able to take account of, such as timing and number of pregnancy losses may be required to identify those at greatest cardiovascular risk., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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26. Benchmarking of several material constitutive models for tribology, wear, and other mechanical deformation simulations of Ti6Al4V.
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Liu C, Goel S, Llavori I, Stolf P, Giusca CL, Zabala A, Kohlscheen J, Paiva JM, Endrino JL, Veldhuis SC, and Fox Rabinovich GS
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- Algorithms, Alloys, Pressure, Software, Stress, Mechanical, Surface Properties, Tensile Strength, Biocompatible Materials chemistry, Engineering standards, Materials Testing methods, Titanium chemistry
- Abstract
Use of an alpha-beta (multiphase HCP-BCC) titanium alloy, Ti6Al4V, is ubiquitous in a wide range of engineering applications. The previous decade of finite element analysis research on various titanium alloys for numerous biomedical applications especially in the field of orthopedics has led to the development of more than half a dozen material constitutive models, with no comparison available between them. Part of this problem stems from the complexity of developing a vectorised user-defined material subroutine (VUMAT) and the different conditions (strain rate, temperature and composition of material) in which these models are experimentally informed. This paper examines the extant literature to review these models and provides quantitative benchmarking against the tabulated material model and a power law model of Ti6Al4V taking the test case of a uniaxial tensile and cutting simulation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
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- 2019
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27. Changes in Cardiac Morphology and Function in Individuals With Diabetes Mellitus: The UK Biobank Cardiovascular Magnetic Resonance Substudy.
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Jensen MT, Fung K, Aung N, Sanghvi MM, Chadalavada S, Paiva JM, Khanji MY, de Knegt MC, Lukaschuk E, Lee AM, Barutcu A, Maclean E, Carapella V, Cooper J, Young A, Piechnik SK, Neubauer S, and Petersen SE
- Subjects
- Adult, Aged, Comorbidity, Female, Heart Function Tests, Humans, Image Interpretation, Computer-Assisted, Male, Middle Aged, Stroke Volume, United Kingdom, Diabetic Cardiomyopathies diagnostic imaging, Diabetic Cardiomyopathies physiopathology, Magnetic Resonance Imaging, Cine methods
- Abstract
Background: Diabetes mellitus (DM) is associated with increased risk of cardiovascular disease. Detection of early cardiac changes before manifest disease develops is important. We investigated early alterations in cardiac structure and function associated with DM using cardiovascular magnetic resonance imaging., Methods: Participants from the UK Biobank Cardiovascular Magnetic Resonance Substudy, a community cohort study, without known cardiovascular disease and left ventricular ejection fraction ≥50% were included. Multivariable linear regression models were performed. The investigators were blinded to DM status., Results: A total of 3984 individuals, 45% men, (mean [SD]) age 61.3 (7.5) years, hereof 143 individuals (3.6%) with DM. There was no difference in left ventricular (LV) ejection fraction (DM versus no DM; coefficient [95% CI]: -0.86% [-1.8 to 0.5]; P =0.065), LV mass (-0.13 g/m
2 [-1.6 to 1.3], P =0.86), or right ventricular ejection fraction (-0.23% [-1.2 to 0.8], P =0.65). However, both LV and right ventricular volumes were significantly smaller in DM, (LV end-diastolic volume/m2 : -3.46 mL/m2 [-5.8 to -1.2], P =0.003, right ventricular end-diastolic volume/m2 : -4.2 mL/m2 [-6.8 to -1.7], P =0.001, LV stroke volume/m2 : -3.0 mL/m2 [-4.5 to -1.5], P <0.001; right ventricular stroke volume/m2 : -3.8 mL/m2 [-6.5 to -1.1], P =0.005), LV mass/volume: 0.026 (0.01 to 0.04) g/mL, P =0.006. Both left atrial and right atrial emptying fraction were lower in DM (right atrial emptying fraction: -6.2% [-10.2 to -2.1], P =0.003; left atrial emptying fraction:-3.5% [-6.9 to -0.1], P =0.043). LV global circumferential strain was impaired in DM (coefficient [95% CI]: 0.38% [0.01 to 0.7], P =0.045)., Conclusions: In a low-risk general population without known cardiovascular disease and with preserved LV ejection fraction, DM is associated with early changes in all 4 cardiac chambers. These findings suggest that diabetic cardiomyopathy is not a regional condition of the LV but affects the heart globally.- Published
- 2019
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28. Quantitative CMR population imaging on 20,000 subjects of the UK Biobank imaging study: LV/RV quantification pipeline and its evaluation.
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Attar R, Pereañez M, Gooya A, Albà X, Zhang L, de Vila MH, Lee AM, Aung N, Lukaschuk E, Sanghvi MM, Fung K, Paiva JM, Piechnik SK, Neubauer S, Petersen SE, and Frangi AF
- Subjects
- Biological Specimen Banks, Female, Humans, Imaging, Three-Dimensional, Male, Pattern Recognition, Automated, United Kingdom, Heart Ventricles diagnostic imaging, Image Interpretation, Computer-Assisted methods, Magnetic Resonance Imaging, Cine methods, Models, Statistical, Neural Networks, Computer
- Abstract
Population imaging studies generate data for developing and implementing personalised health strategies to prevent, or more effectively treat disease. Large prospective epidemiological studies acquire imaging for pre-symptomatic populations. These studies enable the early discovery of alterations due to impending disease, and enable early identification of individuals at risk. Such studies pose new challenges requiring automatic image analysis. To date, few large-scale population-level cardiac imaging studies have been conducted. One such study stands out for its sheer size, careful implementation, and availability of top quality expert annotation; the UK Biobank (UKB). The resulting massive imaging datasets (targeting ca. 100,000 subjects) has put published approaches for cardiac image quantification to the test. In this paper, we present and evaluate a cardiac magnetic resonance (CMR) image analysis pipeline that properly scales up and can provide a fully automatic analysis of the UKB CMR study. Without manual user interactions, our pipeline performs end-to-end image analytics from multi-view cine CMR images all the way to anatomical and functional bi-ventricular quantification. All this, while maintaining relevant quality controls of the CMR input images, and resulting image segmentations. To the best of our knowledge, this is the first published attempt to fully automate the extraction of global and regional reference ranges of all key functional cardiovascular indexes, from both left and right cardiac ventricles, for a population of 20,000 subjects imaged at 50 time frames per subject, for a total of one million CMR volumes. In addition, our pipeline provides 3D anatomical bi-ventricular models of the heart. These models enable the extraction of detailed information of the morphodynamics of the two ventricles for subsequent association to genetic, omics, lifestyle habits, exposure information, and other information provided in population imaging studies. We validated our proposed CMR analytics pipeline against manual expert readings on a reference cohort of 4620 subjects with contour delineations and corresponding clinical indexes. Our results show broad significant agreement between the manually obtained reference indexes, and those automatically computed via our framework. 80.67% of subjects were processed with mean contour distance of less than 1 pixel, and 17.50% with mean contour distance between 1 and 2 pixels. Finally, we compare our pipeline with a recently published approach reporting on UKB data, and based on deep learning. Our comparison shows similar performance in terms of segmentation accuracy with respect to human experts., (Crown Copyright © 2019. Published by Elsevier B.V. All rights reserved.)
- Published
- 2019
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29. Physical activity and left ventricular trabeculation in the UK Biobank community-based cohort study.
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Woodbridge SP, Aung N, Paiva JM, Sanghvi MM, Zemrak F, Fung K, and Petersen SE
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- Aged, Cohort Studies, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, United Kingdom, Cardiomyopathies pathology, Exercise, Heart Ventricles pathology
- Abstract
Objective: Vigorous physical activity (PA) in highly trained athletes has been associated with heightened left ventricular (LV) trabeculation extent. It has therefore been hypothesised that LV trabeculation extent may participate in exercise-induced physiological cardiac remodelling. Our cross-sectional observational study aimed to ascertain whether there is a 'dose-response' relationship between PA and LV trabeculation extent and whether this could be identified at opposite PA extremes., Methods: In a cohort of 1030 individuals from the community-based UK Biobank study (male/female ratio: 0.84, mean age: 61 years), PA was measured via total metabolic equivalent of task (MET) min/week and 7-day average acceleration, and trabeculation extent via maximal non-compaction/compaction ratio (NC/C) in long-axis images of cardiovascular magnetic resonance studies. The relationship between PA and NC/C was assessed by multivariate regression (adjusting for potential confounders) as well as between demographic, anthropometric and LV phenotypic parameters and NC/C., Results: There was no significant linear relationship between PA and NC/C (full adjustment, total MET-min/week: ß=-0.0008, 95% CI -0.039 to -0.037, p=0.97; 7-day average acceleration: ß=-0.047, 95% CI -0.110 to -0.115, p=0.13, per IQR increment in PA), or between extreme PA quintiles (full adjustment, total MET-min/week: ß=-0.026, 95% CI -0.146 to -0.094, p=0.67; 7-day average acceleration: ß=-0.129, 95% CI -0.299 to -0.040, p=0.49), across all adjustment levels. A negative relationship was identified between left ventricular ejection fraction and NC/C, significantly modified by PA (ß difference=-0.006, p=0.03)., Conclusions: In a community-based general population cohort, there was no relationship at, or between, extremes, between PA and NC/C, suggesting that at typical general population PA levels, trabeculation extent is not influenced by PA changes., Competing Interests: Competing interests: SEP provides consultancy to Circle Cardiovascular Imaging Inc, Calgary, Canada. Other authors have no conflicts of interest to declare., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)
- Published
- 2019
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30. Automated quality control in image segmentation: application to the UK Biobank cardiovascular magnetic resonance imaging study.
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Robinson R, Valindria VV, Bai W, Oktay O, Kainz B, Suzuki H, Sanghvi MM, Aung N, Paiva JM, Zemrak F, Fung K, Lukaschuk E, Lee AM, Carapella V, Kim YJ, Piechnik SK, Neubauer S, Petersen SE, Page C, Matthews PM, Rueckert D, and Glocker B
- Subjects
- Automation, Humans, Predictive Value of Tests, Quality Control, Reproducibility of Results, United Kingdom, Heart diagnostic imaging, Image Interpretation, Computer-Assisted standards, Magnetic Resonance Imaging standards
- Abstract
Background: The trend towards large-scale studies including population imaging poses new challenges in terms of quality control (QC). This is a particular issue when automatic processing tools such as image segmentation methods are employed to derive quantitative measures or biomarkers for further analyses. Manual inspection and visual QC of each segmentation result is not feasible at large scale. However, it is important to be able to automatically detect when a segmentation method fails in order to avoid inclusion of wrong measurements into subsequent analyses which could otherwise lead to incorrect conclusions., Methods: To overcome this challenge, we explore an approach for predicting segmentation quality based on Reverse Classification Accuracy, which enables us to discriminate between successful and failed segmentations on a per-cases basis. We validate this approach on a new, large-scale manually-annotated set of 4800 cardiovascular magnetic resonance (CMR) scans. We then apply our method to a large cohort of 7250 CMR on which we have performed manual QC., Results: We report results used for predicting segmentation quality metrics including Dice Similarity Coefficient (DSC) and surface-distance measures. As initial validation, we present data for 400 scans demonstrating 99% accuracy for classifying low and high quality segmentations using the predicted DSC scores. As further validation we show high correlation between real and predicted scores and 95% classification accuracy on 4800 scans for which manual segmentations were available. We mimic real-world application of the method on 7250 CMR where we show good agreement between predicted quality metrics and manual visual QC scores., Conclusions: We show that Reverse classification accuracy has the potential for accurate and fully automatic segmentation QC on a per-case basis in the context of large-scale population imaging as in the UK Biobank Imaging Study.
- Published
- 2019
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31. Association Between Ambient Air Pollution and Cardiac Morpho-Functional Phenotypes: Insights From the UK Biobank Population Imaging Study.
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Aung N, Sanghvi MM, Zemrak F, Lee AM, Cooper JA, Paiva JM, Thomson RJ, Fung K, Khanji MY, Lukaschuk E, Carapella V, Kim YJ, Munroe PB, Piechnik SK, Neubauer S, and Petersen SE
- Subjects
- Aged, Air Pollutants toxicity, Biological Specimen Banks, Cardiovascular Diseases diagnostic imaging, Cardiovascular Diseases etiology, Cardiovascular Diseases physiopathology, Cross-Sectional Studies, Databases, Factual, Environmental Exposure, Female, Humans, Magnetic Resonance Imaging, Cine, Male, Middle Aged, Nitrogen Oxides analysis, Particulate Matter toxicity, Phenotype, United Kingdom, Ventricular Function, Left physiology, Ventricular Remodeling, Air Pollutants chemistry, Cardiovascular Diseases diagnosis
- Abstract
Background: Exposure to ambient air pollution is strongly associated with increased cardiovascular morbidity and mortality. Little is known about the influence of air pollutants on cardiac structure and function. We aim to investigate the relationship between chronic past exposure to traffic-related pollutants and the cardiac chamber volume, ejection fraction, and left ventricular remodeling patterns after accounting for potential confounders., Methods: Exposure to ambient air pollutants including particulate matter and nitrogen dioxide was estimated from the Land Use Regression models for the years between 2005 and 2010. Cardiac parameters were measured from cardiovascular magnetic resonance imaging studies of 3920 individuals free from pre-existing cardiovascular disease in the UK Biobank population study. The median (interquartile range) duration between the year of exposure estimate and the imaging visit was 5.2 (0.6) years. We fitted multivariable linear regression models to investigate the relationship between cardiac parameters and traffic-related pollutants after adjusting for various confounders., Results: The studied cohort was 62±7 years old, and 46% were men. In fully adjusted models, particulate matter with an aerodynamic diameter <2.5 μm concentration was significantly associated with larger left ventricular end-diastolic volume and end-systolic volume (effect size = 0.82%, 95% CI, 0.09-1.55%, P =0.027; and effect size = 1.28%, 95% CI, 0.15-2.43%, P =0.027, respectively, per interquartile range increment in particulate matter with an aerodynamic diameter <2.5 μm) and right ventricular end-diastolic volume (effect size = 0.85%, 95% CI, 0.12-1.58%, P =0.023, per interquartile range increment in particulate matter with an aerodynamic diameter <2.5 μm). Likewise, higher nitrogen dioxide concentration was associated with larger biventricular volume. Distance from the major roads was the only metric associated with lower left ventricular mass (effect size = -0.74%, 95% CI, -1.3% to -0.18%, P =0.01, per interquartile range increment). Neither left and right atrial phenotypes nor left ventricular geometric remodeling patterns were influenced by the ambient pollutants., Conclusions: In a large asymptomatic population with no prevalent cardiovascular disease, higher past exposure to particulate matter with an aerodynamic diameter <2.5 μm and nitrogen dioxide was associated with cardiac ventricular dilatation, a marker of adverse remodeling that often precedes heart failure development., Competing Interests: Disclosures Dr Petersen provides consultancy to Circle Cardiovascular Imaging Inc, Calgary, Canada. The other authors report no conflicts.
- Published
- 2018
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32. The impact of menopausal hormone therapy (MHT) on cardiac structure and function: Insights from the UK Biobank imaging enhancement study.
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Sanghvi MM, Aung N, Cooper JA, Paiva JM, Lee AM, Zemrak F, Fung K, Thomson RJ, Lukaschuk E, Carapella V, Kim YJ, Harvey NC, Piechnik SK, Neubauer S, and Petersen SE
- Subjects
- Aging, Comorbidity, Cross-Sectional Studies, Female, Follow-Up Studies, Humans, Magnetic Resonance Imaging, Menopause, Middle Aged, Postmenopause, Risk Factors, Stroke Volume drug effects, United Kingdom epidemiology, Cardiovascular Diseases prevention & control, Heart Atria drug effects, Heart Ventricles drug effects, Hormone Replacement Therapy
- Abstract
Background: The effect of menopausal hormone therapy (MHT)-previously known as hormone replacement therapy-on cardiovascular health remains unclear and controversial. This cross-sectional study examined the impact of MHT on left ventricular (LV) and left atrial (LA) structure and function, alterations in which are markers of subclinical cardiovascular disease, in a population-based cohort., Methods: Post-menopausal women who had never used MHT and those who had used MHT ≥3 years participating in the UK Biobank who had undergone cardiovascular magnetic resonance (CMR) imaging and free of known cardiovascular disease were included. Multivariable linear regression was performed to examine the relationship between cardiac parameters and MHT use ≥3 years. To explore whether MHT use on each of the cardiac outcomes differed by age, multivariable regression models were constructed with a cross-product of age and MHT fitted as an interaction term., Results: Of 1604 post-menopausal women, 513 (32%) had used MHT ≥3 years. In the MHT cohort, median age at menopause was 50 (IQR: 45-52) and median duration of MHT was 8 years. In the non-MHT cohort, median age at menopause was 51 (IQR: 48-53). MHT use was associated with significantly lower LV end-diastolic volume (122.8 ml vs 119.8 ml, effect size = -2.4%, 95% CI: -4.2% to -0.5%; p = 0.013) and LA maximal volume (60.2 ml vs 57.5 ml, effect size = -4.5%, 95% CI: -7.8% to -1.0%; p = 0.012). There was no significant difference in LV mass. MHT use significantly modified the effect between age and CMR parameters; MHT users had greater decrements in LV end-diastolic volume, LV end-systolic volume and LA maximal volume with advancing age., Conclusions: MHT use was not associated with adverse, subclinical changes in cardiac structure and function. Indeed, significantly smaller LV and LA chamber volumes were observed which have been linked to favourable cardiovascular outcomes. These findings represent a novel approach to examining MHT's effect on the cardiovascular system.
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- 2018
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33. Tribological and Wear Performance of Nanocomposite PVD Hard Coatings Deposited on Aluminum Die Casting Tool.
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Paiva JM, Fox-Rabinovich G, Locks Junior E, Stolf P, Seid Ahmed Y, Matos Martins M, Bork C, and Veldhuis S
- Abstract
In the aluminum die casting process, erosion, corrosion, soldering, and die sticking have a significant influence on tool life and product quality. A number of coatings such as TiN, CrN, and (Cr,Al)N deposited by physical vapor deposition (PVD) have been employed to act as protective coatings due to their high hardness and chemical stability. In this study, the wear performance of two nanocomposite AlTiN and AlCrN coatings with different structures were evaluated. These coatings were deposited on aluminum die casting mold tool substrates (AISI H13 hot work steel) by PVD using pulsed cathodic arc evaporation, equipped with three lateral arc-rotating cathodes (LARC) and one central rotating cathode (CERC). The research was performed in two stages: in the first stage, the outlined coatings were characterized regarding their chemical composition, morphology, and structure using glow discharge optical emission spectroscopy (GDOES), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. Surface morphology and mechanical properties were evaluated by atomic force microscopy (AFM) and nanoindentation. The coating adhesion was studied using Mersedes test and scratch testing. During the second stage, industrial tests were carried out for coated die casting molds. In parallel, tribological tests were also performed in order to determine if a correlation between laboratory and industrial tests can be drawn. All of the results were compared with a benchmark monolayer AlCrN coating. The data obtained show that the best performance was achieved for the AlCrN/Si₃N₄ nanocomposite coating that displays an optimum combination of hardness, adhesion, soldering behavior, oxidation resistance, and stress state. These characteristics are essential for improving the die mold service life. Therefore, this coating emerges as a novelty to be used to protect aluminum die casting molds., Competing Interests: The authors declare no conflict of interest.
- Published
- 2018
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34. Fully-automated left ventricular mass and volume MRI analysis in the UK Biobank population cohort: evaluation of initial results.
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Suinesiaputra A, Sanghvi MM, Aung N, Paiva JM, Zemrak F, Fung K, Lukaschuk E, Lee AM, Carapella V, Kim YJ, Francis J, Piechnik SK, Neubauer S, Greiser A, Jolly MP, Hayes C, Young AA, and Petersen SE
- Subjects
- Aged, Algorithms, Automation, Female, Heart Diseases physiopathology, Humans, Linear Models, Male, Middle Aged, Observer Variation, Predictive Value of Tests, Reproducibility of Results, United Kingdom, Heart Diseases diagnostic imaging, Image Interpretation, Computer-Assisted methods, Magnetic Resonance Imaging, Cine methods, Stroke Volume, Ventricular Function, Left
- Abstract
UK Biobank, a large cohort study, plans to acquire 100,000 cardiac MRI studies by 2020. Although fully-automated left ventricular (LV) analysis was performed in the original acquisition, this was not designed for unsupervised incorporation into epidemiological studies. We sought to evaluate automated LV mass and volume (Siemens syngo InlineVF versions D13A and E11C), against manual analysis in a substantial sub-cohort of UK Biobank participants. Eight readers from two centers, trained to give consistent results, manually analyzed 4874 UK Biobank cases for LV end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and LV mass (LVM). Agreement between manual and InlineVF automated analyses were evaluated using Bland-Altman analysis and the intra-class correlation coefficient (ICC). Tenfold cross-validation was used to establish a linear regression calibration between manual and InlineVF results. InlineVF D13A returned results in 4423 cases, whereas InlineVF E11C returned results in 4775 cases and also reported LVM. Rapid visual assessment of the E11C results found 178 cases (3.7%) with grossly misplaced contours or landmarks. In the remaining 4597 cases, LV function showed good agreement: ESV -6.4 ± 9.0 ml, 0.853 (mean ± SD of the differences, ICC) EDV -3.0 ± 11.6 ml, 0.937; SV 3.4 ± 9.8 ml, 0.855; and EF 3.5 ± 5.1%, 0.586. Although LV mass was consistently overestimated (29.9 ± 17.0 g, 0.534) due to larger epicardial contours on all slices, linear regression could be used to correct the bias and improve accuracy. Automated InlineVF results can be used for case-control studies in UK Biobank, provided visual quality control and linear bias correction are performed. Improvements between InlineVF D13A and InlineVF E11C show the field is rapidly advancing, with further improvements expected in the near future.
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- 2018
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35. Effect of Built-Up Edge Formation during Stable State of Wear in AISI 304 Stainless Steel on Machining Performance and Surface Integrity of the Machined Part.
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Ahmed YS, Fox-Rabinovich G, Paiva JM, Wagg T, and Veldhuis SC
- Abstract
During machining of stainless steels at low cutting -speeds, workpiece material tends to adhere to the cutting tool at the tool-chip interface, forming built-up edge (BUE). BUE has a great importance in machining processes; it can significantly modify the phenomenon in the cutting zone, directly affecting the workpiece surface integrity, cutting tool forces, and chip formation. The American Iron and Steel Institute (AISI) 304 stainless steel has a high tendency to form an unstable BUE, leading to deterioration of the surface quality. Therefore, it is necessary to understand the nature of the surface integrity induced during machining operations. Although many reports have been published on the effect of tool wear during machining of AISI 304 stainless steel on surface integrity, studies on the influence of the BUE phenomenon in the stable state of wear have not been investigated so far. The main goal of the present work is to investigate the close link between the BUE formation, surface integrity and cutting forces in the stable sate of wear for uncoated cutting tool during the cutting tests of AISI 304 stainless steel. The cutting parameters were chosen to induce BUE formation during machining. X-ray diffraction (XRD) method was used for measuring superficial residual stresses of the machined surface through the stable state of wear in the cutting and feed directions. In addition, surface roughness of the machined surface was investigated using the Alicona microscope and Scanning Electron Microscopy (SEM) was used to reveal the surface distortions created during the cutting process, combined with chip undersurface analyses. The investigated BUE formation during the stable state of wear showed that the BUE can cause a significant improvement in the surface integrity and cutting forces. Moreover, it can be used to compensate for tool wear through changing the tool geometry, leading to the protection of the cutting tool from wear., Competing Interests: The authors declare no conflict of interest.
- Published
- 2017
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36. Reference ranges for cardiac structure and function using cardiovascular magnetic resonance (CMR) in Caucasians from the UK Biobank population cohort.
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Petersen SE, Aung N, Sanghvi MM, Zemrak F, Fung K, Paiva JM, Francis JM, Khanji MY, Lukaschuk E, Lee AM, Carapella V, Kim YJ, Leeson P, Piechnik SK, and Neubauer S
- Subjects
- Age Factors, Aged, Female, Humans, Male, Middle Aged, Observer Variation, Predictive Value of Tests, Reference Values, Reproducibility of Results, Sex Factors, Stroke Volume, United Kingdom, Atrial Function, Left, Atrial Function, Right, Biological Specimen Banks, Heart diagnostic imaging, Heart physiology, Magnetic Resonance Imaging standards, Ventricular Function, Left, Ventricular Function, Right, White People
- Abstract
Background: Cardiovascular magnetic resonance (CMR) is the gold standard method for the assessment of cardiac structure and function. Reference ranges permit differentiation between normal and pathological states. To date, this study is the largest to provide CMR specific reference ranges for left ventricular, right ventricular, left atrial and right atrial structure and function derived from truly healthy Caucasian adults aged 45-74., Methods: Five thousand sixty-five UK Biobank participants underwent CMR using steady-state free precession imaging at 1.5 Tesla. Manual analysis was performed for all four cardiac chambers. Participants with non-Caucasian ethnicity, known cardiovascular disease and other conditions known to affect cardiac chamber size and function were excluded. Remaining participants formed the healthy reference cohort; reference ranges were calculated and were stratified by gender and age (45-54, 55-64, 65-74)., Results: After applying exclusion criteria, 804 (16.2%) participants were available for analysis. Left ventricular (LV) volumes were larger in males compared to females for absolute and indexed values. With advancing age, LV volumes were mostly smaller in both sexes. LV ejection fraction was significantly greater in females compared to males (mean ± standard deviation [SD] of 61 ± 5% vs 58 ± 5%) and remained static with age for both genders. In older age groups, LV mass was lower in men, but remained virtually unchanged in women. LV mass was significantly higher in males compared to females (mean ± SD of 53 ± 9 g/m
2 vs 42 ± 7 g/m2 ). Right ventricular (RV) volumes were significantly larger in males compared to females for absolute and indexed values and were smaller with advancing age. RV ejection fraction was higher with increasing age in females only. Left atrial (LA) maximal volume and stroke volume were significantly larger in males compared to females for absolute values but not for indexed values. LA ejection fraction was similar for both sexes. Right atrial (RA) maximal volume was significantly larger in males for both absolute and indexed values, while RA ejection fraction was significantly higher in females., Conclusions: We describe age- and sex-specific reference ranges for the left ventricle, right ventricle and atria in the largest validated normal Caucasian population.- Published
- 2017
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37. New drugs, new challenges for dermatologists: mucocutaneous ulcers secondary to everolimus.
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Pasin VP, Pereira AR, Carvalho KA, Paiva JM, Enokihara MM, and Porro AM
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- Adult, Anus Diseases pathology, Female, Humans, Immunocompetence immunology, Mouth pathology, Skin Ulcer immunology, Skin Ulcer pathology, Stomatitis immunology, Stomatitis pathology, TOR Serine-Threonine Kinases antagonists & inhibitors, Anus Diseases chemically induced, Everolimus adverse effects, Immunosuppressive Agents adverse effects, Kidney Transplantation adverse effects, Skin Ulcer chemically induced, Stomatitis chemically induced
- Abstract
Everolimus, a mammalian target of rapamycin inhibitor, is an emerging drug, which is being increasingly applied in oncology and solid organ transplantation. Oral ulcers are a frequent side effect associated with this immunosupressor. We report the case of a renal transplant recipient who developed disfiguring oral and perianal ulcers secondary to everolimus's toxicity. This is probably the first report of perianal involvement. Dermatologists need to be aware of the potential mucocutaneous adverse effects related to these new drugs that are becoming evermore common in our clinical practice.
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- 2015
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38. Artifact level produced by different femoral head prostheses in CT imaging: diamond coated silicon nitride as total hip replacement material.
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Rodrigues SP, Paiva JM, De Francesco S, Amaral MI, Oliveira FJ, and Silva RF
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- Reproducibility of Results, Tomography, X-Ray Computed, Arthroplasty, Replacement, Hip, Artifacts, Coated Materials, Biocompatible, Diamond, Hip Prosthesis, Silicon Compounds
- Abstract
Commercial femoral head prostheses (cobalt-chromium alloy, yttria partially stabilized zirconia (Y-PSZ) and alumina) and new silicon nitride ceramic ones (nanocrystalline diamond coated and uncoated) were compared in terms of artifact level production by computed tomography (CT). Pelvis examination by CT allows the correct diagnosis of some pathologies (e.g. prostate and colon cancer) and the evaluation of the prosthesis-bone interface in post-operative joint surgery. Artifact quantification is rarely seen in literature despite having a great potential to grade biomaterials according to their imaging properties. Materials' characteristics (density and effective atomic number), size and geometry of the prostheses can cause more or less artifact. A quantification procedure based on the calculation of four statistical parameters for the Hounsfield pixel values (mean, standard deviation, mean squared error and worst case error) is presented. CT sequential and helical scanning modes were performed. Results prove the artifact reproducibility and indicate that the cobalt-chromium and Y-PSZ are the most artifact-inducing materials, while alumina and silicon nitride (diamond coated and uncoated) ceramic ones present a low level of artifact. Considering the excellent biocompatibility and biotribological behaviour reported in earlier works, combined with the high medical imaging quality here assessed, diamond coated silicon nitride ceramics are arising as new materials for joint replacement.
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- 2013
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39. Bartholin's gland cysts: management with carbon-dioxide laser vaporization.
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Figueiredo AC, Duarte PE, Gomes TP, Borrego JM, and Marques CA
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- Adolescent, Adult, Female, Humans, Lasers, Gas adverse effects, Middle Aged, Recurrence, Retrospective Studies, Young Adult, Bartholin's Glands, Cysts surgery, Laser Therapy adverse effects, Lasers, Gas therapeutic use, Vulvar Diseases surgery
- Abstract
Purpose: To evaluate the effectiveness, recurrence rate, and complications of carbon-dioxide laser vaporization in the treatment of Bartholin's gland cysts., Methods: A retrospective study including 127 patients with symptomatic Bartholin' gland cysts submitted to carbon-dioxide laser vaporization at our institution from January 2005 to June 2011. Patients with Bartholin's gland abscesses and those suspected of having neoplasia were excluded. All procedures were performed in an outpatient setting under local anaesthesia. Clinical records were reviewed for demographic characteristics, anatomic parameters, intraoperative and postoperative complications, and follow-up data. Data were stored and analyzed in Microsoft Excel® 2007 software. A descriptive statistical analysis was performed, and its results were expressed as frequency (percentage) or mean±standard deviation. Complication, recurrence, and cure rates were calculated., Results: The mean age of the patients was 37.3±9.5 years-old (range from 18 to 61 years-old). Seventy percent (n=85) of them were multiparous. The most common symptom was pain and 47.2% (n=60) of patients had a history of previous medical and/or surgical treatment for Bartholin's gland abscesses. Mean cyst size was 2.7±0.9 cm. There were three (2.4%) cases of minor intraoperative bleeding. Overall, there were 17 (13.4%) recurrences within a mean of 14.6 months (range from 1 to 56 months): ten Bartholin's gland abscesses and seven recurrent cysts requiring reintervention. The cure rate after single laser treatment was 86.6%. Among the five patients with recurrent disease that had a second laser procedure, the cure rate was 100%., Conclusions: At this institution, carbon-dioxide laser vaporization seems to be a safe and effective procedure for the treatment of Bartholin's gland cysts.
- Published
- 2012
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40. Occurrence of filamentous fungi and yeasts in three different drinking water sources.
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Pereira VJ, Basílio MC, Fernandes D, Domingues M, Paiva JM, Benoliel MJ, Crespo MT, and San Romão MV
- Subjects
- Bacteria classification, Bacteria isolation & purification, Enterobacteriaceae isolation & purification, Environmental Monitoring, Fresh Water chemistry, Fungi classification, Yeasts classification, Fresh Water microbiology, Fungi isolation & purification, Water Supply analysis, Yeasts isolation & purification
- Abstract
In order to determine the occurrence of fungi in different drinking water sources and capture variability in terms of matrix composition and seasonal effects, surface water, spring water, and groundwater samples were collected in numerous sampling events. The occurrence and significance of fungi detected in the different water sources are reported and discussed in terms of colony-forming units per millilitre and by the identification of the most frequently detected isolates, at the species level, based on morphology and other phenotypic characters. All the samples were also analyzed in terms of total coliforms and Escherichia coli that are widely monitored bacteria considered as microbiology indicators of water quality. All the groundwater samples showed significantly lower levels of total coliforms, E. coli, and fungi compared to the surface and spring water samples. No significant correlations were found between the levels of fungi detected in all the matrices and the physico-chemical parameters and bacteria regularly monitored by drinking water utilities. Fifty-two fungi isolates were identified in this study, most of which have never been described to occur in water sources. The results obtained show that fungi occur widely in drinking water sources and that further studies should be conducted to address their biodegradation potential as well as if the drinking water treatment processes currently used are effective in removing these organisms and the potential secondary metabolites produced.
- Published
- 2009
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41. Occurrence of Fasciola hepatica (Linnaeus, 1758) infection in Brazilian cattle of Minas Gerais, Brazil.
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Lima Wdos S, Soares LR, Barçante TA, Guimaraes MP, and Barçante JM
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- Animals, Brazil epidemiology, Cattle, Cattle Diseases diagnosis, Fascioliasis diagnosis, Fascioliasis epidemiology, Cattle Diseases epidemiology, Fascioliasis veterinary
- Abstract
Fasciolosis is a parasitic disease which is caused by digenetic trematodes, such as Fasciola hepatica, and which occurs worldwide. The disease causes significant economic losses in cattle because of the reduction in milk and meat production and because the parasitized livers have no economic value. Also, abortion and mortality rates increase. To determine the occurrence and dispersal of F. hepatica in the state of Minas Gerais, fecal samples were collected from bovines aged 12 months and older between April 2005 and April 2006. The bovines came from 1,251 rural farms of 120 municipalities/cities in Minas Gerais. Water was collected to ascertain the presence of the intermediate host in the properties where infected bovines were found. A total of 16 municipalities had infected bovines and 13 had the presence of Lymnaea columella. We detected infected bovines in 70% of the rural farms visited in the municipality of Itajubá. Itajubá was also found to have infected snails with the larval stage of F. hepatica. The results revealed that infection by F. hepatica in bovines of Minas Gerais was associated with the presence of the intermediate host and favorable epidemiological factors, drawing attention to the necessity of adopting proper control measures in the area.
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- 2009
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42. Efficacy and safety of abciximab on acute myocardial infarction treated with percutaneous coronary interventions: a meta-analysis of randomized, controlled trials.
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de Queiroz Fernandes Araújo JO, Veloso HH, Braga De Paiva JM, Filho MW, and Vincenzo De Paola AA
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- Abciximab, Antibodies, Monoclonal adverse effects, Anticoagulants administration & dosage, Chemotherapy, Adjuvant, Female, Hemorrhage chemically induced, Heparin administration & dosage, Humans, Immunoglobulin Fab Fragments adverse effects, Male, Middle Aged, Myocardial Infarction mortality, Myocardial Infarction therapy, Myocardial Revascularization, Randomized Controlled Trials as Topic, Recurrence, Stents, Angioplasty, Balloon, Coronary, Antibodies, Monoclonal therapeutic use, Immunoglobulin Fab Fragments therapeutic use, Myocardial Infarction drug therapy, Platelet Glycoprotein GPIIb-IIIa Complex antagonists & inhibitors
- Abstract
Objective: To evaluate the efficacy and safety of abciximab following acute myocardial infarction (AMI) treated with percutaneous coronary interventions., Methods: A meta-analysis of randomized controlled trials of platelet glycoprotein IIb/IIIa inhibitor abciximab as adjunctive therapy to percutaneous coronary interventions for AMI was performed. Main outcomes measured were: (1) mortality, (2) reinfarction, (3) target vessel revascularization (TVR), (4) major cardiac events (MACE) that were a composite endpoint of death, reinfarction, and TVR, and (5) major bleeding., Results: Six trials randomized 3755 patients who were followed for a mean of 5.5 months. Compared with the control, abciximab significantly reduced mortality (OR 0.70, 95% CI 0.50-0.97), TVR (0.79, 95% CI 0.65-0.96) and MACE (0.76, 95% CI 0.65-0.90). Reduction on TVR and MACE was confirmed in stent patients, but not in balloon angioplasty patients. Abciximab was associated with an increased risk of major bleeding (OR 1.39, 95% CI 1.03-1.87), but bleeding was observed only with a 100U/kg heparin bolus followed by a maintenance infusion (OR 1.89, 95% CI 1.10-3.28) and not with a bolus of 70U/kg (OR 1.22, 95% CI 0.85-1.73)., Conclusions: Abciximab, as adjunctive therapy to percutaneous coronary interventions, reduces mortality, TVR and MACE following AMI. The reduction of clinical outcomes occurs with stent implantation but not with balloon angioplasty. A 70U/kg heparin bolus must be used to avoid major bleeding.
- Published
- 2004
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43. Hand-assisted Thoracoscopic Surgery causes less postoperative pain than limited thoracotomy after cessation of epidural analgesia.
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Paiva JM and Wright GM
- Abstract
Background: Hand-assisted Thoracoscopic Surgery (HATS) is a novel minimally invasive technique for performing procedures conventionally performed by posterolateral thoracotomy. HATS overcomes a major drawback of thoracoscopic surgery in allowing full manual palpation of the lungs via a subcostal (mini-Kocher's) incision under videoscopic guidance, avoiding a thoracotomy, when the indication is pulmonary metastasectomy with curative intent or resection of undiagnosed lung nodules. It is postulated HATS may produce improved postoperative quality of life outcomes compared to thoracotomy., Aims: To determine if HATS compared to limited posterolateral thoracotomy causes less postoperative pain after cessation of epidural anaesthesia., Methods: Fifty-two patients were prospectively randomised to receive a limited thoracotomy (n=26) or HATS (n=26). Pain scores, measured on a visual analogue scale, were recorded during standard nursing observations and after analgesia demands in the 24h after epidural removal., Results: Pain scores were significantly lower after HATS compared to limited thoracotomy (3.8 versus 5.2, p=0.04). There was no difference in postoperative respiratory function., Conclusion: HATS results in lower postoperative pain after cessation of epidural analgesia. This form of analgesia may therefore not be required, reducing the management complexity, complications and hospital stay associated with its use. SHORT ABSTRACT: Hand-assisted Thoracoscopic Surgery (HATS) is a novel technique allowing full manual lung palpation as an adjunct to Video-assisted Thoracoscopic Surgery (VATS). Fifty-two patients were prospectively randomised to receive limited thoracotomy or HATS. Pain scores were significantly lower after HATS compared to thoracotomy, indicating epidural analgesia may not be required.
- Published
- 2004
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44. Angiostrongylus vasorum (Baillet, 1866) Kamensky, 1905: emergence of third-stage larvae from infected Biomphalaria glabrata snails.
- Author
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Barçante TA, Barçante JM, Dias SR, and Lima Wdos S
- Subjects
- Angiostrongylus isolation & purification, Angiostrongylus pathogenicity, Animals, Larva, Light, Movement, Time Factors, Angiostrongylus growth & development, Biomphalaria parasitology
- Abstract
Biomphalaria glabrata snails were experimentally infected with Angiostrongylus vasorum first-stage larvae and divided into four groups of 30 snails. To assess the shedding of third-stage larvae (L3), the snails were maintained under different stimuli: group 1 60 W light bulb for 24 h, group 2 37 degrees C water bath for 24 h, group 3 room temperature (23-25 degrees C) for 24 h, Group 4 room temperature (23-25 degrees C) for up to 15 days. After 24 h, a total of 512 A. vasorum L3, alive and active, were released by snails from group 1, while 2,446 L3 were released from group 2 and five L3 from group 3. After 15 days, snails from group 4 released a total of 44 L3. To evaluate the infectivity of A. vasorum L3, two mongrel dogs were successfully infected with L3 released by snails from groups 1 and 2, confirming that the infection of dogs with A. vasorum L3 was possible, independently of ingestion of the mollusk intermediate host. The results shown in these experiments suggest that angiostrongylosis could be directly transmitted to the definitive hosts, with implications for the parasite's life cycle.
- Published
- 2003
- Full Text
- View/download PDF
45. Acute atrial fibrillation during dengue hemorrhagic fever.
- Author
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Horta Veloso H, Ferreira Júnior JA, Braga de Paiva JM, Faria Honório J, Junqueira Bellei NC, and Vicenzo de Paola AA
- Subjects
- Amiodarone therapeutic use, Anti-Arrhythmia Agents therapeutic use, Atrial Fibrillation diagnosis, Atrial Fibrillation drug therapy, Electrocardiography, Humans, Male, Middle Aged, Atrial Fibrillation etiology, Severe Dengue complications
- Abstract
Dengue fever is a viral infection transmitted by the mosquito, Aedes aegypti. Cardiac rhythm disorders, such as atrioventricular blocks and ventricular ectopic beats, appear during infection and are attributed to viral myocarditis. However, supraventricular arrhythmias have not been reported. We present a case of acute atrial fibrillation, with a rapid ventricular rate, successfully treated with intravenous amiodarone, in a 62-year-old man with dengue hemorrhagic fever, who had no structural heart disease.
- Published
- 2003
- Full Text
- View/download PDF
46. Hand-assisted thoracoscopic surgery.
- Author
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Wright GM, Clarke CP, and Paiva JM
- Subjects
- Humans, Lung surgery, Thoracoscopy methods
- Abstract
Hand-assisted thoracoscopic surgery is a novel minimally invasive approach for performing techniques conventionally performed by posterolateral thoracotomy. Hand-assisted thoracoscopic surgery overcomes one of the major drawbacks of minimally invasive thoracic surgery in allowing full manual palpation of the lungs through a subcostal incision under video guidance, while avoiding a thoracotomy when the indication is pulmonary metastasectomy with curative intent or resection of undiagnosed lung nodules. The technique may result in improved quality of life outcomes compared with a thoracotomy.
- Published
- 2003
- Full Text
- View/download PDF
47. Mortality and reinfarction reduction with primary stent implantation compared with primary balloon angioplasty.
- Author
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Araújo JO, Veloso HH, and Paiva JM
- Subjects
- Blood Vessel Prosthesis Implantation, Humans, Recurrence, Survival Analysis, Treatment Outcome, Angioplasty, Balloon, Coronary, Myocardial Infarction mortality, Myocardial Infarction therapy, Stents
- Published
- 2002
- Full Text
- View/download PDF
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