24 research outputs found
Repeatability of quantitative18F-FLT uptake measurements in solid tumors: an individual patient data multi-center meta-analysis
INTRODUCTION: 3'-deoxy-3'-[18F]fluorothymidine (18F-FLT) positron emission tomography (PET) provides a non-invasive method to assess cellular proliferation and response to antitumor therapy. Quantitative18F-FLT uptake metrics are being used for evaluation of proliferative response in investigational setting, however multi-center repeatability needs to be established. The aim of this study was to determine the repeatability of18F-FLT tumor uptake metrics by re-analyzing individual patient data from previously published reports using the same tumor segmentation method and repeatability metrics across cohorts. METHODS: A systematic search in PubMed, EMBASE.com and the Cochrane Library from inception-October 2016 yielded five18F-FLT repeatability cohorts in solid tumors.18F-FLT avid lesions were delineated using a 50% isocontour adapted for local background on test and retest scans. SUVmax, SUVmean, SUVpeak, proliferative volume and total lesion uptake (TLU) were calculated. Repeatability was assessed using the repeatability coefficient (RCâ=â1.96Â ĂÂ SD of test-retest differences), linear regression analysis, and the intra-class correlation coefficient (ICC). The impact of different lesion selection criteria was also evaluated. RESULTS: Images from four cohorts containing 30 patients with 52 lesions were obtained and analyzed (ten in breast cancer, nine in head and neck squamous cell carcinoma, and 33 in non-small cell lung cancer patients). A good correlation was found between test-retest data for all18F-FLT uptake metrics (R2ââ„â0.93; ICCââ„â0.96). Best repeatability was found for SUVpeak(RC: 23.1%), without significant differences in RC between different SUV metrics. Repeatability of proliferative volume (RC: 36.0%) and TLU (RC: 36.4%) was worse than SUV. Lesion selection methods based on SUVmaxââ„â4.0 improved the repeatability of volumetric metrics (RC: 26-28%), but did not affect the repeatability of SUV metrics. CONCLUSIONS: In multi-center studies, differences â„Â 25% in18F-FLT SUV metrics likely represent a true change in tumor uptake. Larger differences are required for FLT metrics comprising volume estimates when no lesion selection criteria are applied
Characteristics of COVID-19 Patients with Bacterial Co-infection Admitted to the Hospital from the Emergency Department in a Large Regional Healthcare System
Introduction
The rate of bacterial coinfection with SARSâCoVâ2 is poorly defined. The decision to administer antibiotics early in the course of SARSâCoVâ2 infection depends on the likelihood of bacterial coinfection.
Methods
We performed a retrospective chart review of all patients admitted through the emergency department with confirmed SARSâCoVâ2 infection over a 6âweek period in a large healthcare system in the United States. Blood and respiratory culture results were abstracted and adjudicated by multiple authors. The primary outcome was the rate of bacteremia. We secondarily looked to define clinical or laboratory features associated with bacteremia.
Results
There were 542 patients admitted with confirmed SARSâCoVâ2 infection, with an average age of 62.8 years. Of these, 395 had blood cultures performed upon admission, with six true positive results (1.1% of the total population). An additional 14 patients had positive respiratory cultures treated as true pathogens in the first 72âh. Low blood pressure and elevated white blood cell count, neutrophil count, blood urea nitrogen, and lactate were statistically significantly associated with bacteremia. Clinical outcomes were not statistically significantly different between patients with and without bacteremia.
Conclusions
We found a low rate of bacteremia in patients admitted with confirmed SARSâCoVâ2 infection. In hemodynamically stable patients, routine antibiotics may not be warranted in this population
Mood alterations following an indoor and outdoor exercise program in healthy elderly women
Effets d'un programme d'activitĂ© physique rĂ©crĂ©ative d'une durĂ©e de 12 semaines sur la santĂ© psychique de femmes sĂ©dentaires ĂągĂ©es de 60 Ă 75 ans. Mesure des sentiments et sensations positives (bien-ĂȘtre, vitalitĂ©, engagement positif), de la fatigue en fonction du niveau d'activitĂ© physique
DEPTH CAMERAS ON UAVs: A FIRST APPROACH
Accurate depth information retrieval of a scene is a field under investigation in the research areas of photogrammetry, computer vision and robotics. Various technologies, active, as well as passive, are used to serve this purpose such as laser scanning, photogrammetry and depth sensors, with the latter being a promising innovative approach for fast and accurate 3D object reconstruction using a broad variety of measuring principles including stereo vision, infrared light or laser beams. In this study we investigate the use of the newly designed Stereolab's ZED depth camera based on passive stereo depth calculation, mounted on an Unmanned Aerial Vehicle with an ad-hoc setup, specially designed for outdoor scene applications. Towards this direction, the results of its depth calculations and scene reconstruction generated by Simultaneous Localization and Mapping (SLAM) algorithms are compared and evaluated based on qualitative and quantitative criteria with respect to the ones derived by a typical Structure from Motion (SfM) and Multiple View Stereo (MVS) pipeline for a challenging cultural heritage application
Does a three-month exercise programme enhance the subjective view of mobility level amongst elderly women ?
Une étude visant à évaluer les effets d'un programme d'exercice de douze semaines sur le niveau de performance de 40 femmes ùgées sédentaires (de 60 à 75 ans) et à examiner le minimum d'exercice hebdomadaire nécessaire pour produire des changements. Les variables testées - les vingt mouvements quotidiens les plus fréquents - ont été évaluées à partir de l'échelle Likert