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101.
Introduction and objectivesCardiac device-related infections (CDRI) may be life-threatening and require early and accurate diagnosis. The aims of this study were to analyze the performance of positron emission tomography-computed tomography (PET/CT) in suspected CDRI, to assess changes to the initial diagnosis, and to identify a clinical subgroup deriving the greatest benefit from this imaging modality.MethodsRetrospective study including patients evaluated by PET/CT for suspected CDRI from 2011 to 2018. We assessed PET/CT performance and the agreement between the initial, post-PET and definitive diagnoses. We also assessed changes in the diagnosis, depending on initial clinical suspicion, to identify patients deriving the greatest benefit from PET/CT.ResultsWe included 44 patients. The prevalence of endocarditis was 57%. The sensitivity and specificity of PET/CT for the diagnosis of infective endocarditis were 0.84 and 0.95, respectively. Post-PET diagnosis improved the initial diagnosis by 45%. PET/CT correctly reclassified 57% of patients with initial suspicion of generator pocket infection by detecting lead infection.ConclusionsPET/CT showed high diagnostic performance in suspected of CDRI and significantly improved the conventional diagnostic approach, especially in patients with initial suspicion of focal infection.  相似文献   
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Introduction and objectivesCOVID-19 is currently causing high mortality and morbidity worldwide. Information on cardiac injury is scarce. We aimed to evaluate cardiovascular damage in patients with COVID-19 and determine the correlation of high-sensitivity cardiac-specific troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) with the severity of COVID-19.MethodsWe included 872 consecutive patients with confirmed COVID-19 from February to April 2020. We tested 651 patients for high-sensitivity troponin T (hs-TnT) and 506 for NT-proBNP on admission. Cardiac injury was defined as hs-TnT > 14 ng/L, the upper 99th percentile. Levels of NT-proBNP > 300 pg/mL were considered related to some extent of cardiac injury. The primary composite endpoint was 30-day mortality or mechanical ventilation (MV).ResultsCardiac injury by hs-TnT was observed in 34.6% of our COVID-19 patients. Mortality or MV were higher in cardiac injury than noncardiac injury patients (39.1% vs 9.1%). Hs-TnT and NT-proBNP levels were independent predictors of death or MV (HR, 2.18; 95%CI, 1.23-3.83 and 1.87 (95%CI, 1.05-3.36), respectively) and of mortality alone (HR, 2.91; 95%CI, 1.211-7.04 and 5.47; 95%CI, 2.10-14.26, respectively). NT-ProBNP significantly improved the troponin model discrimination of mortality or MV (C-index 0.83 to 0.84), and of mortality alone (C-index 0.85 to 0.87).ConclusionsMyocardial injury measured at admission was a common finding in patients with COVID-19. It reliably predicted the occurrence of mortality and need of MV, the most severe complications of the disease. NT-proBNP improved the prognostic accuracy of hs-TnT.  相似文献   
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We perform rapid spontaneous Raman 2D imaging in light-sheet microscopy using continuous wave lasers and interferometric tunable filters. By angularly tuning the filter, the cut-on/off edge transitions are scanned along the excited Stokes wavelengths. This allows obtaining cumulative intensity profiles of the scanned vibrational bands, which are recorded on image stacks; resembling a spectral version of the knife-edge technique to measure intensity profiles. A further differentiation of the stack retrieves the Raman spectra at each pixel of the image which inherits the 3D resolution of the host light sheet system. We demonstrate this technique using solvent solutions and composites of polystyrene beads and lipid droplets immersed in agar and by imaging the C–H (2800-3100cm−1) region in a C. elegans worm. The image acquisition time results in 4 orders of magnitude faster than confocal point scanning Raman systems, allowing the possibility of performing fast spontaneous Raman·3D-imaging on biological samples.OCIS codes: (170.3880) Medical and biological imaging, (180.5655) Raman microscopy, (300.6450) Spectroscopy, Raman, (110.4234) Multispectral and hyperspectral imaging  相似文献   
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Brown adipose tissue (BAT) is an endocrine adipose tissue with attributes to dissipate energy as heat in response to changes in temperature and diet. Infrared thermography (IRT) has been studied in recent years in the assessment of BAT thermogenesis, as an option to positron emission tomography - computed tomography (PET-CT), because of several advantages. We performed a systematic review on the use of IRT in BAT assessment. Comprehensive online search was performed in different databases. The QUADAS 2 tool was used to evaluate studies’ quality. 12 studies fit the inclusion criteria, whereas only one of these was considered of low risk of bias. 10 studies were favorable to IRT appliance in BAT evaluation, observing elevation of supraclavicular skin temperature correlated with BAT activity. Studies were heterogeneous in design, and a meta-analysis was precluded. Further studies with similar methodologies are needed. Conclusion: Despite the large number of published methodologies, IRT is a promising method for detecting BAT activation. Current knowledge already allows a better understanding of thermography to improve and standardize the technique.

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