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This article builds on recent work of the first three authors where a notion of congruence modules in higher codimension is introduced. The main results are a criterion for detecting regularity of local rings in terms of congruence modules, and a more refined version of a result tracking the change of congruence modules under deformation. Number theoretic applications include the construction of canonical lines in certain Galois cohomology groups arising from adjoint motives of Hilbert modular forms.
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To evaluate deep learning-based calcium segmentation and quantification on ECG-gated cardiac CT scans compared with manual evaluation. Automated calcium quantification was performed using a neural network based on mask regions with convolutional neural networks (R-CNNs) for multi-organ segmentation. Manual evaluation of calcium was carried out using proprietary software. This is a retrospective study of archived data. This study used 40 patients to train the segmentation model and 110 patients were used for the validation of the algorithm. The Pearson correlation coefficient between the reference actual and the computed predictive scores shows high level of correlation (0.84; P < .001) and high limits of agreement (±1.96 SD; -2000, 2000) in Bland-Altman plot analysis. The proposed method correctly classifies the risk group in 75.2% and classifies the subjects in the same group. In total, 81% of the predictive scores lie in the same categories and only seven patients out of 110 were more than one category off. For the presence/absence of coronary artery calcifications, the deep learning model achieved a sensitivity of 90% and a specificity of 94%. Fully automated model shows good correlation compared with reference standards. Automating process reduces evaluation time and optimizes clinical calcium scoring without additional resources.
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Falso Aneurisma , Aneurisma , Aneurisma Coronário , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/etiologia , Falso Aneurisma/cirurgia , Aneurisma Coronário/diagnóstico por imagem , Aneurisma Coronário/etiologia , Aneurisma Coronário/cirurgia , Angiografia Coronária , Ponte de Artéria Coronária/efeitos adversos , Vasos Coronários , Humanos , Veia Safena/diagnóstico por imagem , Veia Safena/transplanteRESUMO
OBJECTIVE: To understand the transmission dynamics of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in a hospital outbreak to inform infection control actions. DESIGN: Retrospective cohort study. SETTING: General medical and elderly inpatient wards in a hospital in England. METHODS: Coronavirus disease 2019 (COVID-19) patients were classified as community or healthcare associated by time from admission to onset or positivity using European Centre for Disease Prevention and Control definitions. COVID-19 symptoms were classified as asymptomatic, nonrespiratory, or respiratory. Infectiousness was calculated from 2 days prior to 14 days after symptom onset or positive test. Cases were defined as healthcare-associated COVID-19 when infection was acquired from the wards under investigation. COVID-19 exposures were calculated based on symptoms and bed proximity to an infectious patient. Risk ratios and adjusted odds ratios (aORs) were calculated from univariable and multivariable logistic regression. RESULTS: Of 153 patients, 65 were COVID-19 patients and 45 of these were healthcare-associated cases. Exposure to a COVID-19 patient with respiratory symptoms was associated with healthcare-associated infection irrespective of proximity (aOR, 3.81; 95% CI, 1.6.3-8.87). Nonrespiratory exposure was only significant within 2.5 m (aOR, 5.21; 95% CI, 1.15-23.48). A small increase in risk ratio was observed for exposure to a respiratory patient for >1 day compared to 1 day from 2.04 (95% CI, 0.99-4.22) to 2.36 (95% CI, 1.44-3.88). CONCLUSIONS: Respiratory exposure anywhere within a 4-bed bay was a risk, whereas nonrespiratory exposure required bed distance ≤2.5 m. Standard infection control measures required beds to be >2 m apart. Our findings suggest that this may be insufficient to stop SARS-CoV-2 transmission. We recommend improving cohorting and further studies into bed distance and transmission factors.
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COVID-19 , Infecção Hospitalar , Humanos , Idoso , COVID-19/epidemiologia , SARS-CoV-2 , Infecção Hospitalar/epidemiologia , Hospitais de Distrito , Estudos Retrospectivos , Atenção à SaúdeRESUMO
Prostate cancer is the most common malignancy in men, in general. Most patients diagnosed with prostate cancer have localized disease confined to the prostate. A small percentage of patients with aggressive tumors will progress to develop local, extracapsular tumor extension and distant metastases. The aim of prostate cancer management is to identify and treat those patients with aggressive disease before they develop locally advanced or metastatic disease, and to avoid overtreating indolent tumors, which are unlikely to be life threatening. Imaging has been shown to be valuable in local staging of prostate cancer and as an aid to the management of clinically significant disease. In this article, we discuss the different established imaging modalities and emerging techniques for prostate cancer imaging in patients with clinically localized disease who may be suitable for radical treatment.
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Diagnóstico por Imagem/métodos , Neoplasias da Próstata/diagnóstico , Gerenciamento Clínico , Humanos , Masculino , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias da Próstata/patologiaRESUMO
Heart lesions in patients with rheumatoid arthritis (RA) are well documented in literature; however, in the majority of cases these are incidental findings at postmortem. Most patients do not require cardiac surgical intervention unless they develop complications such as significant valvular regurgitation. Patients with RA often require orthopedic operations and therefore a bioprosthetic valve replacement is normally advocated to avoid problems related to anticoagulation. We report a case of a 64-year-old woman with seropositive RA who had undergone bioprosthetic aortic valve replacement three years previously. She re-presented with early prosthetic valve failure due to accelerated degeneration and calcification. This was treated successfully with redo replacement with a mechanical prosthesis. Here, we discuss our experience and debate the various valve choices available that should be considered in patients with rheumatoid disease.
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Valva Aórtica , Artrite Reumatoide/complicações , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas , Falha de Prótese , Feminino , Seguimentos , Doenças das Valvas Cardíacas/complicações , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Pessoa de Meia-Idade , Reoperação , Fatores de TempoRESUMO
INTRODUCTION: Since April 2002, collection and publication of surgeon-specific data in adult cardiac surgery has become mandatory in the UK. It has been suggested that this may discourage consultants from allowing trainees to perform cases. The aim of this study was to attempt to analyse the effect of the introduction of surgeon-specific data (SSD) on surgical training in a large cardiac surgical centre. PATIENTS AND METHODS: A retrospective analysis was performed on 2111 consecutive patients undergoing elective coronary artery bypass surgery, aortic and mitral valve surgery at Southampton General Hospital between April 2000 and April 2004. Results were analysed and compared over a 2-year period prior to and a 2-year period following the introduction of SSD. RESULTS: There were no changes in the overall mortality rate following the introduction of SSD. SSD was associated with a reduction in the overall proportion of cases performed by trainees (49% versus 42.8%; P = 0.004) and, in particular, a reduction in the proportion of aortic and mitral valve procedures performed by trainees. In addition, the proportion of cases performed by the trainees without consultant supervision declined significantly following SSD (18.7% versus 10.4%; P < 0.001). CONCLUSIONS: Publication of surgeon-specific data has coincided with a decrease in both the proportion and variety of cases performed by trainees.
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Procedimentos Cirúrgicos Cardíacos/estatística & dados numéricos , Educação Médica Continuada/normas , Corpo Clínico Hospitalar/educação , Adulto , Valva Aórtica/cirurgia , Procedimentos Cirúrgicos Cardíacos/educação , Procedimentos Cirúrgicos Cardíacos/mortalidade , Consultores , Ponte de Artéria Coronária/estatística & dados numéricos , Inglaterra , Humanos , Corpo Clínico Hospitalar/estatística & dados numéricos , Valva Mitral/cirurgia , Estudos RetrospectivosRESUMO
OBJECTIVE: Loss-of-function mutations of the ATP-binding cassette transporter A1 (ABCA1) gene cause Tangier disease, a rare genetic disorder with accumulation of lipid-laden macrophages and increased risk of atherosclerosis. Common variants of this gene may be a genetic factor for atherosclerosis in the general population. This study was performed to test the reported association between the -565C>T polymorphism and atherosclerosis severity and to investigate whether this variant per se had an effect on promoter activity of the ABCA1 gene. METHODS AND RESULTS: A cohort of patients with coronary atherosclerosis were genotyped for the -565C>T polymorphism. Logistic regression analyses showed that homozygotes of the -565T allele had greatest mean number of diseased coronary arteries, particular in nonsmokers. Real-time reverse-transcriptase polymerase chain reaction showed that in atherosclerotic plaques removed from patients undergoing endarteretomy, ABCA1 expression levels were lowest in those who had the T/T genotype and highest in those of the C/C genotype. Transfection and reporter assays demonstrated that in cultured macrophages, the -565T allelic promoter had a lower activity in driving gene expression than the -565C allelic promoter. Electrophoretic mobility shift assays displayed differential binding of nuclear proteins to the 2 alleles. CONCLUSIONS: These results indicate that the -565C>T polymorphism has an allele-specific effect on ABCA1 gene expression and provide further evidence of a genotypic effect on coronary atherosclerosis severity. The study showed that the ABCA1 gene -565C>T polymorphism was associated with severity of coronary atherosclerosis in a cohort of patients from Southern England and that this sequence variant per se had an effect on promoter activity of the ABCA1 gene. The data support the notion that common ABCA1 gene variants can contribute to interindividual variability in atherosclerosis susceptibility and severity.