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Misung Han Baolian Yang Brice Fernandez Marisa Lafontaine Paula Alcaide‐Leon Angela Jakary Brian L. Burns Melanie A. Morrison Javier E. Villanueva‐Meyer Susan M. Chang Suchandrima Banerjee Janine M. Lupo 《NMR in biomedicine》2021,34(1)
Although combined spin‐ and gradient‐echo (SAGE) dynamic susceptibility‐contrast (DSC) MRI can provide perfusion quantification that is sensitive to both macrovessels and microvessels while correcting for T1‐shortening effects, spatial coverage is often limited in order to maintain a high temporal resolution for DSC quantification. In this work, we combined a SAGE echo‐planar imaging (EPI) sequence with simultaneous multi‐slice (SMS) excitation and blipped controlled aliasing in parallel imaging (blipped CAIPI) at 3 T to achieve both high temporal resolution and whole brain coverage. Two protocols using this sequence with multi‐band (MB) acceleration factors of 2 and 3 were evaluated in 20 patients with treated gliomas to determine the optimal scan parameters for clinical use. ΔR2*(t) and ΔR2(t) curves were derived to calculate dynamic signal‐to‐noise ratio (dSNR), ΔR2*‐ and ΔR2‐based relative cerebral blood volume (rCBV), and mean vessel diameter (mVD) for each voxel. The resulting SAGE DSC images acquired using MB acceleration of 3 versus 2 appeared visually similar in terms of image distortion and contrast. The difference in the mean dSNR from normal‐appearing white matter (NAWM) and that in the mean dSNR between NAWM and normal‐appearing gray matter were not statistically significant between the two protocols. ΔR2*‐ and ΔR2‐rCBV maps and mVD maps provided unique contrast and spatial heterogeneity within tumors. 相似文献
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Kelsey J. Zenti Meaghan M. Meyer Nancee V. Waterbury Jason A. Egge 《Primary Care Diabetes》2021,15(3):578-581
BackgroundAn estimated 35 million individuals in the United States have diabetes. The American Diabetes Association recommends metformin as first-line pharmacologic treatment. The primary objective of this study was to evaluate the metformin initiation rate in veterans with recently identified type 2 diabetes.MethodsVeterans with new onset type 2 diabetes were identified using National Veterans Health Administration Data. Retrospective information was obtained from those with a first A1C ≥ 6.5% (48 mmol/mol) between 2013 and 2018. Veterans with at least one additional A1C < 6.5% (48 mmol/mol) documented in the three years prior to the A1C diagnostic for diabetes were included in the analysis.ResultsA total of 144,180 veterans were included. Of those, 45,776 (31.7%) were started on metformin within one year of diabetes diagnosis. The median time to metformin initiation was 12 days and median time to initiation of any anti-hyperglycemic was 11 days. Approximately 16,000 veterans were referred for lifestyle interventions within 90 days.ConclusionMetformin initiation occurred in fewer patients than expected given metformin is a generic, well-tolerated medication recommended as first-line pharmacologic treatment option regardless of A1C. Further studies are needed to assess the barriers of initiating metformin at time of diabetes diagnosis. 相似文献
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Visar Vela Darius Juskevicius Magdalena M. Gerlach Peter Meyer Anne Graber Gieri Cathomas Stefan Dirnhofer Alexandar Tzankov 《Hematological oncology》2020,38(3):284-292
The majority of ocular adnexal (OA) lymphomas (OAL) are extranodal marginal zone lymphomas (MZL). First high throughput sequencing (HTS) studies on OA-MZL showed inconsistent results and the distribution of mutations in reactive lymphoid lesions of this anatomic region has not yet been sufficiently addressed. We characterized OAL and lymphoid lesions of the OA by targeted HTS. The study included 34 OA-MZL, 11 chronic conjunctivitis, five mature small cell B-cell lymphomas spreading to the OA, five diseases with increase of IgG4+ plasma cells, three Burkitt lymphomas (BL), three diffuse large B-cell lymphomas (DLBCL), three mantle cell lymphomas, three idiopathic orbital inflammations/orbital pseudo tumors (PT), and three OA lymphoid hyperplasia. All cases were negative for Chlamydia. The mutational number was highest in BL and lowest in PT. The most commonly (and exclusively) mutated gene in OA-MZL was TNFAIP3 (10 of 34 cases). Altogether, 20 out of 34 patients harbored mutually exclusive mutations of either TNFAIP3, BCL10, MYD88, ATM, BRAF, or NFKBIE, or nonexclusive mutations of IRF8, TNFRSF14, KLHL6, and TBL1XR1, all encoding for NK-κB pathway compounds or regulators. Thirteen patients (38%) had, to a great part, mutually exclusive mutations of chromatin modifier-encoding genes: KMT2D, CREBBP, BCL7A, DNMT3A, EP300, or HIST1H1E. Only four patients harbored co-occurring mutations of genes encoding for NK-κB compounds and chromatin modifiers. Finally, PTEN, KMT2D, PRDM1, and HIST1H2BK mutations were observable in reactive lymphoid lesions too, while such instances were devoid of NF-κB compound mutations and/or mutations of acetyltransferase-encoding genes. In conclusion, 80% of OA-MZL display mutations of either NK-κB compounds or chromatin modifiers. Lymphoid lesions of the OA bearing NF-κB compound mutations and/or mutations of acetyltransferase-encoding genes highly likely represent lymphomas. 相似文献
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Schmitz Jan Jansen Stefanie Meyer Moritz Hinkelbein Jochen 《Notfall & Rettungsmedizin》2022,25(4):285-293
Notfall + Rettungsmedizin - Tauchunfälle sind vergleichsweise selten und stellen (Erst‑)Helfer vor besondere Herausforderungen. Sie müssen schnell und kompetent behandelt werden, da... 相似文献
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It is recognized that asthma places a significant economic burden on the United States, with a total cost of $81.9 billion total costs including costs incurred by absenteeism and mortality. Severe asthma places a large burden of morbidity on children and their caregivers, including severe exacerbations, medication side effects, increased missed school days leading to impaired school performance, and lower caregiver quality of life. Therefore, we need to take a careful look at how we can make asthma care more efficient and cost effective, especially for those children with severe asthma. The 2019 American Thoracic Society symposium reported in this theme issue presented four aspects of managing severe asthma in children that merit attention including patient variables that affect severe asthma, understanding patient behaviors around medications, the appropriate use of bronchoscopy in diagnosis and management of severe asthma, and also the rational use of biologic therapy. This editorial will summarize key points in each of these reviews and prompt a more careful reading of each contribution. 相似文献
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Military cultural competence has recently gained national attention. Experts have posited that limited outcomes in the treatment of posttraumatic stress disorder and depression in the military may be related to limited familiarity with the military. National surveys have indicated low military cultural competence among providers and limited educational efforts on military culture or pertinent military pathology in medical schools and residency training programs. Military families, with their own unique military cultural identity, have been identified as a population with increased risks associated with deployment. In response to these findings, several curricula regarding military culture have been established and widely distributed. Assessments of military cultural competence have also been developed. The clinical impact of enhanced cultural competence in general has thus far been limited. The military, however, with its highly prescribed cultural identity, may be a model culture for further study. 相似文献