Stratifying the early radiologic trajectory in dyspneic patients with COVID-19 pneumonia

OBJECTIVE: This study aimed to stratify the early pneumonia trajectory on chest radiographs and compare patient characteristics in dyspneic patients with coronavirus disease 2019 (COVID-19). MATERIALS AND METHODS: We retrospectively included 139 COVID-19 patients with dyspnea (87 men, 62.7+/-16.3 years) and serial chest radiographs from January to September 2020. Radiographic pneumonia extent was quantified as a percentage using a previously-developed deep learning algorithm. A group-based trajectory model was used to categorize the pneumonia trajectory after symptom onset during hospitalization. Clinical findings, and outcomes were compared, and Cox regression was performed for survival analysis. RESULTS: Radiographic pneumonia trajectories were categorized into four groups. Group 1 (n = 83, 59.7%) had negligible pneumonia, and group 2 (n = 29, 20.9%) had mild pneumonia. Group 3 (n = 13, 9.4%) and group 4 (n = 14, 10.1%) showed similar considerable pneumonia extents at baseline, but group 3 had decreasing pneumonia extent at 1-2 weeks, while group 4 had increasing pneumonia extent. Intensive care unit admission and mortality were significantly more frequent in groups 3 and 4 than in groups 1 and 2 (P \u3c .05). Groups 3 and 4 shared similar clinical and laboratory findings, but thrombocytopenia ( \u3c 150x103/muL) was exclusively observed in group 4 (P = .016). When compared to groups 1 and 2, group 4 (hazard ratio, 63.3; 95% confidence interval, 7.9-504.9) had a two-fold higher risk for mortality than group 3 (hazard ratio, 31.2; 95% confidence interval, 3.5-280.2), and this elevated risk was maintained after adjusting confounders. CONCLUSION: Monitoring the early radiologic trajectory beyond baseline further prognosticated at-risk COVID-19 patients, who potentially had thrombo-inflammatory responses

Experimental Study on the Acellular Demal Matrix Graft for the Root Coverage in Dog

Mucogingival surgery is a plastic surgical procedure designed to correct defects in the morphology, position, and dimensions of the gingiva surrounding the teeth. Many surgical techniques have been reported in mucogingival surgery. Since these procedures also include the soft tissue esthetic approach, the term periodontal plastic surgery has been proposed to be more appropriate.1 Root coverage is a procedure that falls with this definition, and it has attracted more interest than others

Fabrication and evaluation of bilateral Helmholtz radiofrequency coil for thermo-stable breast image with reduced artifacts

PURPOSE: The positron emission tomography (PET)-magnetic resonance (MR) system is a newly emerging technique that yields hybrid images with high-resolution anatomical and metabolic information. With PET-MR imaging, a definitive diagnosis of breast abnormalities will be possible with high spatial accuracy and images will be acquired for the optimal fusion of anatomic locations. Therefore, we propose a PET-compatible two-channel breast MR coil with minimal disturbance to image acquisition which can be used for simultaneous PET-MR imaging in patients with breast cancer. MATERIALS AND METHODS: For coil design and construction, the conductor loops of the Helmholtz coil were tuned, matched, and subdivided with nonmagnetic components. Element values were optimized with an electromagnetic field simulation. Images were acquired on a GE 600 PET-computed tomography (CT) and GE 3.0 T MR system. For this study, we used the T1-weighted image (volunteer; repetition time (TR), 694 ms; echo time (TE), 9.6 ms) and T2-weighted image (phantom; TR, 8742 ms; TE, 104 ms) with the fast spin-echo sequence. RESULTS: The results of measuring image factors with the proposed radiofrequency (RF) coil and standard conventional RF coil were as follows: signal-to-noise ratio (breast; 207.7 vs. 175.2), percent image uniformity (phantom; 89.22%-91.27% vs. 94.63%-94.77%), and Hounsfield units (phantom; -4.51 vs. 2.38). CONCLUSIONS: Our study focused on the feasibility of proposed two-channel Helmholtz loops (by minimizing metallic components and soldering) for PET-MR imaging and found the comparable image quality to the standard conventional coil. We believe our work will help significantly to improve image quality with the development of a less metallic breast MR coil

Understanding the formation of the metastable ferroelectric phase in hafnia–zirconia solid solution thin films

Hf₁₋ₓZrₓO₂ (x ∼ 0.5–0.7) has been the leading candidate of ferroelectric materials with a fluorite crystal structure showing highly promising compatibility with complementary metal oxide semiconductor devices. Despite the notable improvement in device performance and processing techniques, the origin of its ferroelectric crystalline phase (space group: Pca2₁) formation has not been clearly elucidated. Several recent experimental and theoretical studies evidently showed that the interface and grain boundary energies of the higher symmetry phases (orthorhombic and tetragonal) contribute to the stabilization of the metastable non-centrosymmetric orthorhombic phase or tetragonal phase. However, there was a clear quantitative discrepancy between the theoretical expectation and experiment results, suggesting that the thermodynamic model may not provide the full explanation. This work, therefore, focuses on the phase transition kinetics during the cooling step after the crystallization annealing. It was found that the large activation barrier for the transition from the tetragonal/orthorhombic to the monoclinic phase, which is the stable phase at room temperature, suppresses the phase transition, and thus, plays a critical role in the emergence of ferroelectricity

Determination of Risk Factors for Predicting Bladder-Urethra Injury in Cases of Pelvic Bone Fracture: A Retrospective Single Center Study

Purpose Pelvis fractures are associated with bladder and urethral injury (BUI). The purpose of this study was to identify risk factors associated with BUI in patients with pelvic fracture. Methods Patients (> 18 years) with pelvic injury (N = 314) at our hospital between January 2015 and June 2020 were retrospectively analyzed for age, sex, cause of injury, initial vital signs, urine red blood cell (RBC) count, Glasgow Coma Scale and Abbreviated Injury Scale score, Injury Severity Score, preperitoneal pelvic packing, and femur, lumbar spine, and pelvic fractures. Results Compared with the BUI-absent group, the BUI-present group had a greater percentage of patients who were male (79.2% vs. 55.9%; p = 0.026), had a urine RBC count/high power field (HPF) ≥ 30 (94.4% vs. 38.8%; p < 0.001), underwent preperitoneal pelvic packing (37.5% vs. 18.6%; p = 0.035), had symphysis pubis diastasis (33.3% vs. 11.7%; p = 0.008), and had sacroiliac joint dislocation (54.2% vs. 23.4%; p = 0.001). Independent risk factors associated with BUI were symphysis pubis diastasis [odds ratio (OR) was 3.958 (95% confidence interval: 1.191–13.154); p = 0.025] and a urine RBC count/HPF ≥ 30 [OR = 25.415 (95% confidence interval: 3.252–198.637); p = 0.006]. Of those with BUI, 15 patients were diagnosed at the trauma bay, and 9 had a delayed diagnosis. Conclusion Patients with pelvic injury who display symphysis pubis diastasis or have a urine RBC count/HPF ≥ 30 are at higher risk of BUI, therefore, further BUI investigations should be considered

VEGFR2 but not VEGFR3 governs integrity and remodeling of thyroid angiofollicular unit in normal state and during goitrogenesis

Thyroid gland vasculature has a distinguishable characteristic of endothelial fenestrae, a critical component for proper molecular transport. However, the signaling pathway that critically governs the maintenance of thyroid vascular integrity, including endothelial fenestrae, is poorly understood. Here, we found profound and distinct expression of follicular epithelial VEGF-A and vascular VEGFR2 that were precisely regulated by circulating thyrotropin, while there were no meaningful expression of angiopoietin-Tie2 system in the thyroid gland. Our genetic depletion experiments revealed that VEGFR2, but not VEGFR3, is indispensable for maintenance of thyroid vascular integrity. Notably, blockade of VEGF-A or VEGFR2 not only abrogated vascular remodeling but also inhibited follicular hypertrophy, which led to the reduction of thyroid weights during goitrogenesis. Importantly, VEGFR2 blockade alone was sufficient to cause a reduction of endothelial fenestrae with decreases in thyrotropin-responsive genes in goitrogen-fed thyroids. Collectively, these findings establish follicular VEGF-Avascular VEGFR2 axis as a main regulator for thyrotropindependent thyroid angiofollicular remodeling and goitrogenesis.Peer reviewe