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Zumel-Marne Angela Kundi Michael Castaño-Vinyals Gemma Alguacil Juan Petridou Eleni Th Georgakis Marios K. Morales-Suárez-Varela Maria Sadetzki Siegal Piro Sara Nagrani Rajini Filippini Graziella Hutter Hans-Peter Dikshit Rajesh Woehrer Adelheid Maule Milena Weinmann Tobias Krewski Daniel ′t Mannetje Andrea Momoli Franco Lacour Brigitte Mattioli Stefano Spinelli John J. Ritvo Paul Remen Thomas Kojimahara Noriko Eng Amanda Thurston Angela Lim Hyungryul Ha Mina Yamaguchi Naohito Mohipp Charmaine Bouka Evdoxia Eastman Chelsea Vermeulen Roel Kromhout Hans Cardis Elisabeth 《Journal of neuro-oncology》2020,147(2):427-440
Journal of Neuro-Oncology - We used data from MOBI-Kids, a 14-country international collaborative case–control study of brain tumors (BTs), to study clinical characteristics of the tumors in... 相似文献
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Steven R. Passmore Michael G. Johnson Saleh M. Aloraini Stephan Cooper Mina Aziz Cheryl M. Glazebrook 《Journal of manipulative and physiological therapeutics》2019,42(1):23-33
ObjectiveThe purpose of this study was to quantify the impact of a single lumbar spinal manipulation (SM) intervention on the leg movement performance of degenerative lumbar spinal stenosis (LSS) patients in a small-scale registered randomized clinical trial.MethodsParticipants with LSS (n = 14) were tested at baseline for pain, lumbar range of motion, and behavioral or kinematic motor performance (using an established Fitts’ Law foot-pointing task), then underwent covariate adaptive randomization to receive SM or no intervention. Postintervention all dependent measures were repeated. Experimenters were blinded to patient group allocation. University ethics board approval was attained.ResultsFor the primary outcome movement time, there was no significant difference between groups. As predicted by Fitts’ Law, all participants had longer movement times as task difficulty increased. Secondary kinematic outcomes yielded no significant between-group differences. Consistent with Fitts’ Law, kinematic measures changed significantly with task difficulty. Pairwise comparisons revealed the kinematic variables were more adversely affected by greater movement amplitudes than target size changes. No exploratory differences in pain or lumbar range of motion were observed.ConclusionChanges in motor performance were not observed in this chronic pain population after a single SM intervention compared with a control group. Given the sample size, the study may have been underpowered to detect meaningful differences. Fitts’ Law was observed for the lower extremity–pointing task for an LSS population and may provide an objective measure of motor performance. 相似文献
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Jennifer Novak Yujie Cui Paul Frankel Mina S. Sedrak Scott Glaser Richard Li Sabin Motwani Brian Kavanagh Arya Amini 《Practical radiation oncology》2021,11(3):e263-e266
PurposeTwitter is an increasingly popular social media platform within the health care community. The objective of this analysis is to characterize the profile of radiation oncology–related tweets and Twitter users over the past 6 years.Methods and MaterialsUsing the web-based social media analytics platform Symplur Signals, we filtered tweets containing at least 1 of the following hashtags or key words: #radonc, #radiationoncology, "rad onc," or "radiation oncology." We evaluated radiation oncology–related Twitter activity between October 2014 and March 2020 for tweet frequency, tweet content, and individuals or groups posting tweets. We identified the most influential Twitter users contributing to radiation oncology–related tweets.ResultsFrom 2014 to 2020, the quarterly volume of radiation oncology–related tweets increased from 5027 to 29,763. Physicians contributed the largest growth in tweet volume. Academic radiation oncologists comprise 60% of the most influential Twitter accounts responsible for radiation oncology–related content. The number of radiation-oncology resident physicians on Twitter increased from 25 to 328 over the past 6 years, and 20% of radiation-oncology residency programs have a Twitter account. Seventy-one percent of radiation oncology–related tweets generated direct communication via mentions, and 59% of tweets contain links to external sources, including scientific articles.ConclusionsThe number of physicians contributing radiation oncology–related Twitter content has increased significantly in recent years. Academic radiation oncologists are the primary influencers of radiation oncology–related Twitter activity. Twitter is used by radiation oncologists to both professionally network and discuss findings related to the field. There remains the opportunity for radiation oncologists to broaden their audience on Twitter to encompass a more diverse community, including patients. 相似文献
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Background: Skeletal muscle mitochondrial activity is reduced by?~?50–60% after SCI, resulting in impaired energy expenditure, glucose utilization and insulin sensitivity. Near infra-red spectroscopy (NIRS) is a non-invasive tool that can be used to assess mitochondrial capacity. Objectives: (1) Highlight methodological limitations impacting data acquisition and analysis such as subcutaneous adipose tissue (SAT) thickness, movement artifacts, inadequate muscle stimulation, light interference, and ischemic discomfort. (2) Provide technical considerations to improve data acquisition and analysis. This may serve as guidance to other researchers and clinicians using NIRS. Study Design: cross-sectional observational design. Settings: Clinical research medical center. Participants: Sixteen men with 1?>?year post motor complete SCI. Methods: NIRS signals were obtained from right vastus lateralis muscle utilizing a portable system. Signals were fit to a mono-exponential curve. Outcome Measures: Rate constant and r 2 values for the fit curve, indirectly measures mitochondrial capacity. Results: Only four participants produced data with accepted rate constants of 0.002–0.013?s?1 and r 2 of 0.71–0.87. Applications of studentized residuals ≥2.5 resulted in sparing data from another four participants with rate constants of 0.010–0.018?s?1and r 2 values ranging from 0.86–0.99. Conclusions: Several limitations may challenge the use of NIRS to assess mitochondrial capacity after SCI. Acknowledging these limitations and applying additional data processing techniques may overcome the discussed limitations and facilitate data sparing. 相似文献
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Robert R. Young Chad M. Thompson Harshini R. Dinesdurage Reem H. Elbekai Mina Suh Annette C. Rohr Deborah M. Proctor 《Environmental and molecular mutagenesis》2015,56(7):629-636
The Big Blue® (BB) in vivo mutation assay uses transgenic rodents to measure treatment‐induced mutations in virtually any tissue. The BB assay can be conducted in rats or mice and is ideal for investigating tissue‐specific mutagenic mode of action of tumor induction. Some tissues such as oral mucosa have not been thoroughly studied. Due to the small quantity and cartilaginous nature of oral cavity tissues, development of special prosection and DNA isolation methods was required to permit robust analysis of mutations in these tissues. Improved surgical methods permitted collection of adequate and reproducible quantities of tissue (~45 mg gingiva/buccal and ~30 mg gingiva/palate). Optimized DNA isolation methods included use of liquid nitrogen pulverization, homogenization, nuclei pelleting, digestion, and phenol/chloroform extraction, to yield sufficient quantities of DNA from these tissues. In preliminary optimization work, mutant frequency (MF) in tongue and gingiva was increased in rats exposed to the promutagen, benzo[a]pyrene, and the direct mutagen, N‐ethyl‐N‐nitrosourea. The oral cavity carcinogen, 4‐nitroquinoline‐1‐oxide (4‐NQO; 10 ppm in drinking water; 28 days), was qualified as a positive control for mutagenesis in oral tissues since it caused significant increases in cII MFs in gingiva/palate (50.2‐fold) and gingiva/buccal tissues (21.3‐fold), but not in liver or bone marrow (0.9‐ and 1.4‐fold, respectively). These results are consistent with the observation that 4‐NQO primarily induces tumors in oral cavity. Results also demonstrate the utility of the BB rat mutation assay and optimized methods for investigation of oral cavity mutagenicity, and by extension, analysis of other small and cartilaginous tissues. Environ. Mol. Mutagen. 56:629–636, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Mina Jane Zafar Thomas Kallemose Mostafa Benyahia Lars Bo Ebskov Jeannette
stergaard Penny 《Acta orthopaedica》2020,91(4):444
Background and purpose — Total ankle arthroplasties (TAAs) have larger revision rates than hip and knee implants. We examined the survival rates of our primary TAAs, and what different factors, including the cause of arthritis, affect the success and/or revision rate.Patients and methods — From 2004 to 2016, 322 primary Hintegra TAAs were implanted: the 2nd generation implant from 2004 until mid-2007 and the 3rd generation from late 2007 to 2016. A Cox proportional hazards model evaluated sex, age, primary diagnosis, and implant generation, pre- and postoperative angles and implant position as risk factors for revision.Results — 60 implants (19%) were revised, the majority (n = 34) due to loosening. The 5-year survival rate (95% CI) was 75% (69–82) and the 10-year survival rate was 68% (60–77). There was a reduced risk of revision, per degree of increased postoperative medial distal tibial angle at 0.84 (0.72–0.98) and preoperative talus angle at 0.95 (0.90–1.00), indicating that varus ankles may have a larger revision rate. Generation of implant, sex, primary diagnosis, and most pre- and postoperative radiological angles did not statistically affect revision risk.Interpretation — Our revision rates are slightly above registry rates and well above those of the developer. Most were revised due to loosening; no difference was demonstrated with the 2 generations of implant used. Learning curve and a low threshold for revision could explain the high revision rate.Arthritis in the ankle often develops earlier than in the hip or knee, and 70% have a traumatic etiology (Saltzman et al. 2005, Brown et al. 2006). Total ankle arthroplasty (TAA) can be indicated for severe arthritis in the ankle joint, but the anatomical preconditions, like a small surface area and high stress from compression and torque (Bouguecha et al. 2011, Kakkar and Siddique 2011), makes it less durable than hip and knee prosthetics. The Hintegra TAA, a 3-component mobile bearing, uncemented implant (Hintermann et al. 2004) is widely used and results from the development center demonstrate survival rates of 94% and 84% after 5 and 10 years’ follow-up (Barg et al. 2013). This is considerably more than the survival rates from national registries. Labek et al. (2011) demonstrated that development centers report only half of the revision rate that can be found in the few existing national registers. In a systematic review of primary Agility total ankle arthroplasty (DePuy Synthes Orthopedics, Warsaw, IN, USA), the author (Roukis 2012) found that the incidence of complications increased from 7% to 12%, in studies where the inventor was excluded. Similar results were found by Prissel and Roukis (2013), who found an increased incidence of complications from 6% to 13% in studies where the inventor or faculty consultants were excluded. These studies indicated the risk of selection (inventor) and publication (conflict of interest) bias.Planning and surgical technique, including significant experience, are mandatory for a successful outcome. The better result from development centers may reflect, besides the above-mentioned bias, that there is a long learning curve and that the indication for revision surgery varies.We examined the survival rates of primary Hintegra TAAs performed at Hvidovre Hospital, with revision rate as outcome. We report primary diagnosis for primary TAA and examine whether sex, generation of the implant, preoperative angles and implant position affect the revision rate. 相似文献