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101.
Jeremy Ben-Shoshan Hind Alosaimi Pascal Thériault Lauzier Michele Pighi Yeela Talmor-Barkan Pavel Overtchouk Giuseppe Martucci Marco Spaziano Ariel Finkelstein Hemal Gada Nicolo Piazza 《JACC: Cardiovascular Interventions》2021,14(2):185-194
ObjectivesThe purpose of this study was to assess the concordance between transcatheter aortic valve implantation angles generated by the “double S-curve” and “cusp-overlap” techniques.BackgroundThe “double S-curve” and “cusp-overlap” methods aim to define optimal fluoroscopic projections for transcatheter aortic valve replacement (TAVR) with a self-expandable device.MethodsThe study included 100 consecutive patients undergoing TAVR with self-expanding device planned by multidetector computed tomography. TAVR was performed using the double S-curve model, as a view in which both the aortic valve annulus and delivery catheter planes are displayed perpendicularly on fluoroscopy. Optimal projection according to the cusp-overlap technique was retrospectively generated by overlapping the right and left cups on the multidetector computed tomography annular plane. The angular difference between methods was assessed in spherical 3 dimensions and on the left and right anterior oblique (RAO) and cranial and caudal (CAU) axes.ResultsThe double S-curve and cusp-overlap methods provided views located in the same quadrant, mostly the RAO and CAU, in 92% of patients with a median 3-dimensional angular difference of 10.0° (interquartile range: 5.5° to 17.9°). The 3-dimensional deviation between the average angulation obtained by each method was not statistically significant (1.49°; p = 0.349). No significant differences in average coordinates were noted between the double S-curve and cusp-overlap methods (RAO: 14.7 ± 15.2 vs. 12.9 ± 12.5; p = 0.36; and CAU: 27.0 ± 9.4 vs. 26.9 ± 10.4; p = 0.90). TAVR using the double S-curve was associated with 98% device success, low complication rate, and absence of moderate-to-severe paravalvular leak.ConclusionsThe double S-curve and cusp-overlap methods provide comparable TAVR projections, mostly RAO and CAU. TAVR using the double S-curve model is associated with a high rate of device success and low rate of procedural complications. 相似文献
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103.
Tessa Timmers Rik Ossenkoppele Denise Visser Hayel Tuncel Emma E Wolters Sander CJ Verfaillie Wiesje M van der Flier Ronald Boellaard Sandeep SV Golla Bart NM van Berckel 《Journal of cerebral blood flow and metabolism》2020,40(12):2464
The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods. 相似文献
104.
IntroductionDebates in the literature on youth transitions and on immigrant adaptation acknowledge that recent societal shifts have altered the conditions for young people growing up today. As a result, traditional notions of success may limit our understanding of the mechanisms that lead to differential transitional and adaptation pathways among today's children of immigrants. This study explores the definitions of success among a sample of Bosnian-origin youth in St. Louis.MethodThe analysis is based on the first wave of in-depth qualitative interviews with 58 Bosnian second-generation youth (age 15–23) in St. Louis. Interviews lasted 45–90 min, were conducted in English, transcribed and coded following an inductive analytic logic.ResultsOverall the respondents complemented traditional notions of success, such as material stability and family formation with more subjective indicators such as self-fulfillment and happiness.ConclusionsThe findings highlight the importance for future waves of data collection to trace how definitions of success evolve and how they shape particular trajectories of the youth in our study. On a more general level, these findings urge researchers to incorporate definitions of success that are not primarily based on social and economic status mobility in an effort to generate a more nuanced understanding of the adaptations and transitions to adulthood of today's children of immigrants. 相似文献
105.
《Gaceta sanitaria / S.E.S.P.A.S》2022,36(3):274-277
The Mendelian randomization is an epidemiologic method proposed to control for spurious associations in observational studies. These associations are commonly caused by confusion derived from social, environmental, and behavioral factors, which can be difficult to measure. Mendelian randomization is based on the selection of genetic variants that are used as instrumental variables that influence exposure patterns or are associated with an intermediate phenotype of the disease. The present work aims to discuss how to select the appropriate genetic variants as instrumental variables and to present methodological tools to deal with the limitations of this epidemiological method. The use of instrumental variables for modifiable exposures has the potential to mitigate the effects of common limitations, such as confusion, when robust genetic variants are chosen as instrumental variables. 相似文献
106.
107.
Petr Sedivy Monika Dezortova Miloslav Drobny Michal Dubsky Tereza Dusilova Jan Kovar Milan Hajek 《NMR in biomedicine》2020,33(6)
An unknown intense signal (Pun) with a mean chemical shift of 5.3 ppm was observed in 31P MR spectra from the calf muscles of patients with the diabetic foot syndrome. The aim of the study was to identify the origin of this signal and its potential as a biomarker of muscle injury. Calf muscles of 68 diabetic patients (66.3 ± 8.6 years; body mass index = 28.2 ± 4.3 kg/m2) and 12 age‐matched healthy controls were examined by (dynamic) 31P MRS (3 T system, 31P/1H coil). Phantoms (glucose‐1‐phosphate, Pi and PCr) were measured at pH values of 7.05 and 7.51. At rest, Pun signals with intensities higher than 50% of the Pi intensity were observed in 10 of the 68 examined diabetic subjects. We tested two hypothetical origins of the Pun signal: (1) phosphorus from phosphoesters and (2) phosphorus from extra‐ and intracellular alkaline phosphate pools. 2,3‐diphosphoglycerate and glucose‐1‐phosphate are the only phosphoesters with signals in the chemical shift region close to 5.3 ppm. Both compounds can be excluded: 2,3‐diphosphoglycerate due to the missing second signal component at 6.31 ppm; glucose‐1‐phosphate because its chemical shifts are about 0.2 ppm downfield from the Pi signal (4.9 ppm). If the Pun signal is from phosphate, it represents a pH value of 7.54 ± 0.05. Therefore, it could correspond to signals of Pi in mitochondria. However, patients with critical limb ischemia have rather few mitochondria and so the Pun signal probably originates from interstitia. Our data suggest that the increased Pun signal observed in patients with the diabetic foot syndrome is a biomarker of severe muscular damage. 相似文献
108.
Daniel J. Robbins Natalie E. Taylor Damodaran Narayanan Aaron S. Hess William N. Rose 《Journal of clinical apheresis》2020,35(2):128-130
A 32-year-old male with type I diabetes presented with profound hypoglycemia due to exogenous insulin antibody syndrome in the setting of newly-diagnosed common variable immunodeficiency. Immunomodulatory therapy was not initially effective, but after the initiation of plasma exchange hypoglycemia resolved, and glucose lability improved. 相似文献
109.
110.
Théo Willeman Julia Tonini Cécile Garnaud Sébastien Bailly Peggy Gandia Françoise Stanke-Labesque Danièle Maubon Elodie Gautier-Veyret 《Fundamental & clinical pharmacology》2020,34(2):279-287
Therapeutic drug monitoring (TDM) of antifungal triazole was recommended, except for isavuconazole (ISA) whose target trough concentrations (Cmin) need to be specified. Concerning posaconazole (POS), tablet formulation results in higher exposure but no upper Cmin threshold has been yet proposed. We aimed to investigate the pharmacokinetic–pharmacodynamic relationship of POS and ISA, using a bioassay approach as surrogate marker of antifungal activity, in order to refine the therapeutic Cmin of both antifungals. A bioassay using a cellulose disk diffusion method was performed to determine the growth inhibition zone (GIZ) of POS and ISA on Aspergillus fumigatus and Candida parapsilosis (ISA only). GIZs of plasma from patients undergoing TDM for POS (n = 136) or ISA (n = 40) were determined. GIZs of plasma patients and antifungal Cmin were highly correlated for ISA (A. fumigatus: ρ = 0.942, P < 0.0001; C. parapsilosis: ρ = 0.949, P < 0.0001) and POS (ρ = 0.922, P < 0.0001), and these relationships were represented with a Michaelis–Menten model. Based on this modeling, the recommended thresholds of 0.7, 1, and 1.25 mg/L for the POS Cmin corresponded to 50.1, 55.2, and 59.1% of the maximal GIZ, respectively. We propose an upper threshold of 4.8 mg/L for the POS Cmin and a lower threshold of 2.0 mg/L for the Cmin of ISA, as they respectively corresponded to concentrations leading to 90% and 50% of the maximal GIZ on A. fumigatus. The determination of antifungal activity using this bioassay allowed refining target Cmin of POS and ISA, especially the upper threshold of POS (4.8 mg/L) and the lower threshold of ISA (2.0 mg/L). 相似文献