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31.
Janelle C. Waite Santosh Vardhana Patrick J. Shaw Jung‐Eun Jang Christie‐Ann McCarl Thomas O. Cameron Stefan Feske Michael L. Dustin 《European journal of immunology》2013,43(12):3343-3354
Entry of lymphocytes into secondary lymphoid organs (SLOs) involves intravascular arrest and intracellular calcium ion ([Ca2+]i) elevation. TCR activation triggers increased [Ca2+]i and can arrest T‐cell motility in vitro. However, the requirement for [Ca2+]i elevation in arresting T cells in vivo has not been tested. Here, we have manipulated the Ca2+ release‐activated Ca2+ (CRAC) channel pathway required for [Ca2+]i elevation in T cells through genetic deletion of stromal interaction molecule (STIM) 1 or by expression of a dominant‐negative ORAI1 channel subunit (ORAI1‐DN). Interestingly, the absence of CRAC did not interfere with homing of naïve CD4+ T cells to SLOs and only moderately reduced crawling speeds in vivo. T cells expressing ORAI1‐DN lacked TCR activation induced [Ca2+]i elevation, yet arrested motility similar to control T cells in vitro. In contrast, antigen‐specific ORAI1‐DN T cells had a twofold delayed onset of arrest following injection of OVA peptide in vivo. CRAC channel function is not required for homing to SLOs, but enhances spatiotemporal coordination of TCR signaling and motility arrest. 相似文献
32.
ABSTRACTThis study investigated the sublexical route in writing Chinese characters. Using a writing-to-dictation task, we compared neurotypical participants’ performance on writing a set of 40 characters with homophones sharing different phonetic radicals and another set of 40 characters with homophones sharing the same phonetic radicals. The first set of stimuli was regarded as both syllable-to-character and syllable-to-radical inconsistent, while the second set of stimuli was considered syllable-to-radical consistent but syllable-to-character inconsistent. The results of the error analysis showed that the control participants demonstrated a greater tendency to make errors with preserved phonetic radicals in the second set of stimuli. Furthermore, we conducted the same task with a Chinese brain-injured patient, WCY, who had mild dyslexia and severe dysgraphia associated with mild impairment to the lexical semantic route as shown by the patient’s character writing. The results showed that WCY demonstrated similar error patterns as those of the control participants and a shorter writing time in the second set of stimuli. Altogether, the observations were taken as evidence that supported our claim that a syllable-to-phonetic radical route governs the sublexical route in Chinese character writing. 相似文献
33.
Andrew D. Choi Dustin M. Thomas James Lee Suhny Abbara Ricardo C. Cury Jonathon A. Leipsic Christopher Maroules Prashant Nagpal Michael L. Steigner Dee Dee Wang Michelle C. Williams Irfan Zeb Todd C. Villines Ron Blankstein 《Journal of Cardiovascular Computed Tomography》2021,15(1):2-15
Cardiovascular computed tomography (CCT) is a well-validated non-invasive imaging tool with an ever-expanding array of applications beyond the assessment of coronary artery disease. These include the evaluation of structural heart diseases, congenital heart diseases, peri-procedural electrophysiology applications, and the functional evaluation of ischemia. This breadth requires a robust and diverse training curriculum to ensure graduates of CCT training programs meet minimum competency standards for independent CCT interpretation. This statement from the Society of Cardiovascular Computed Tomography aims to supplement existing societal training guidelines by providing a curriculum and competency framework to inform the development of a comprehensive, integrated training experience for cardiology and radiology trainees in CCT. 相似文献
34.
Beatrice Orso PsyD Dario Arnaldi MD Nicola Girtler PsyD Andrea Brugnolo PsyD Elisa Doglione PsyD Pietro Mattioli MD Erica Biassoni MD Roberto Fancellu MD Federico Massa MD Matteo Bauckneht MD Silvia Chiola MD Silvia Morbelli MD Flavio Nobili MD Matteo Pardini MD 《Movement disorders》2021,36(10):2293-2302
35.
Feld Katharina Feld Dustin Karger Bernd Helmus Janine Schwimmer-Okike Nneka Pfeiffer Heidi Banaschak Sibylle Wittschieber Daniel 《International journal of legal medicine》2021,135(1):235-244
International Journal of Legal Medicine - The shaken baby syndrome (SBS) is a common variant of abusive head trauma (AHT) in infants and toddlers. Data on the legal outcome of such cases are still... 相似文献
36.
Madigan Cory G. Adams Michael B. Chu Chu-Chiao Dinkha Laith R. Farrell Samuel J. Hoard Robert T. Keithler Andrea N. Loudermilk Kevin A. Rouse Jessica Walker Brandon L. Williams Susan G. Wyatt Andrew C. Gore Rosco S. Thomas Dustin M. 《The international journal of cardiovascular imaging》2021,37(12):3583-3588
The International Journal of Cardiovascular Imaging - To compare overall number of downstream tests and total costs between negative exercise stress echocardiograms (ESE) or cardiac computed... 相似文献
37.
Risk factors for complications and readmission after operative fixation of pediatric femur fractures
Amit Momaya Dustin Baker Shawn Gilbert Brent Ponce 《Journal of children's orthopaedics》2015,9(4):307-311
Purpose
Operative fixation of pediatric femur fractures with intramedullary implants has grown in popularity in recent decades. However, risk factors for short-term adverse events and readmission have not been well studied.Methods
Pediatric patients who underwent intramedullary nailing of a femur fracture between 2012 and 2013 were identified from the American College of Surgeons National Surgical Quality Improvement Program database. Risk factors for any adverse event (AAE) and readmission after intramedullary nailing were evaluated using univariate and multivariate analysis.Results
A total of 522 pediatric patients who underwent intramedullary nailing of the femur during the study period were identified. The mean age of this patient cohort was 10.2 ± 3.8 years. Review of the cases revealed that 18 (3.4 %) patients had AAE and that 20 (3.8 %) patients were readmitted, of whom 13 (2.5 %) underwent a reoperation. Independent risk factors for AAE were a cardiac comorbidity [odds ratio (OR) 12.7, 95 % confidence interval (CI) 1.5, 103.7], open fracture (OR 10.2, 95 % CI 1.4, 74.4), and prolonged operative time (OR 17.5, 95 % CI 6.1, 50.5). Independent risk factors for readmission were a central nervous system disorder (OR 4.5, 95 % CI 1.3, 16.2) and a seizure disorder (OR 4.9, 95 % CI 1.0, 23.5).Conclusions
The results of the multivariate analysis suggest that cardiac comorbidities, open fractures, and prolonged operative time increase the risk for AAE and that central nervous system disorders and seizure disorders may increase the risk for readmission. Surgeons should be aware of these risk factors and counsel the families of pediatric patients who undergo intramedullary nailing of femur fractures. 相似文献38.
Discrimination of MHC-derived odors by untrained mice is consistent with divergence in peptide-binding region residues 总被引:1,自引:0,他引:1 下载免费PDF全文
Carroll LS Penn DJ Potts WK 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(4):2187-2192
Genes of the major histocompatibility complex (MHC) play a central role in immune recognition, yet they also influence the odor of individuals. Mice can be trained to distinguish odors mediated by classical MHC loci; however, training can introduce confounding behavioral artifacts. This study demonstrates that mice can distinguish some, but not all, naturally occurring allelic variants at classical MHC loci without prior training. This result suggests that MHC-disassortative mating preferences might operate by means of small MHC-based odor differences, and could therefore contribute to diversifying selection acting on MHC loci. Here we show that odors of two MHC mutant mouse strains (bm1 and bm3) can be distinguished, even after genetic background is controlled by intercrossing strains. These two strains differ by five amino acids, three of which are predicted to chemically contact peptides bound to the peptide-binding region (PBR), the site of antigen presentation for T cell recognition. However, the odors of neither bm1 nor bm3 were distinguished from their parental B6 haplotype after randomizing genomic background, despite discrimination of pure-bred B6 and bm1 strain odors. These combined results suggest that (i) there may be an MHC odor discrimination threshold based on divergence in PBR residues, providing a more logical pattern of MHC-based odor discrimination than found in previous training studies, where discrimination ability was not correlated with PBR divergence; and (ii) additional (non-MHC) mutations that influence odor have accumulated in these strains during the 100 generations of divergence between pure B6 and bm1 strains. 相似文献
39.
Bradley Jacobson Michael Cendoma Jacob Gdovin Kevin Cooney Dustin Bruening 《Journal of Athletic Training》2014,49(1):42-48
Context
The National Athletic Trainers'' Association position statement on acute management of the cervical spine-injured athlete recommended the all-or-nothing endeavor, which involves removing or not removing both helmet and shoulder pads, from equipment-laden American football and ice hockey athletes. However, in supporting research, investigators have not considered alternative protocols.Objective
To measure cervical spine movement (head relative to sternum) produced when certified athletic trainers (ATs) use the all-or-nothing endeavor and to compare these findings with the movement produced using an alternative pack-and-fill protocol, which involves packing the area under and around the cervical neck and head with rolled towels.Design
Crossover study.Setting
Movement analysis laboratory.Patients or Other Participants
Eight male collegiate football players (age = 21.4 ± 1.4 years; height = 1.87 ± 0.02 m; mass = 103.6 ± 12.5 kg).Intervention(s)
Four ATs removed equipment under 4 conditions: removal of helmet only followed by placing the head on the ground (H), removal of the helmet only followed by pack-and-fill (HP), removal of the helmet and shoulder pads followed by placing the head on the ground (HS), and removal of the helmet and shoulder pads followed by pack-and-fill (HSP). Motion capture was used to track the movement of the head with respect to the sternum during equipment removal.Main Outcome Measure(s)
We measured head movement relative to sternum movement (translations and rotations). We used 4 × 4 analyses of variance with repeated measures to compare discrete motion variables (changes in position and total excursions) among protocols and ATs.Results
Protocol HP resulted in a 0.1 ± 0.6 cm rise in head position compared with a 1.4 ± 0.3 cm drop with protocol HS (P < .001). Protocol HP produced 4.9° less total angular excursion (P < .001) and 2.1 cm less total vertical excursion (P < .001) than protocol HS.Conclusions
The pack-and-fill protocol was more effective than shoulder pad removal in minimizing cervical spine movement throughout the equipment-removal process. This study provides evidence for including the pack-and-fill protocol in future treatment recommendations when helmet removal is necessary for on-field care.Key Words: National Athletic Trainers'' Association position statement, pack and fill, motion analysis, helmet removalKey Points
- The pack-and-fill protocol resulted in less overall motion than removal of the helmet and shoulder pads followed by placing the head on the ground, which is currently endorsed by the National Athletic Trainers'' Association.
- Using pack and fill, the athletic trainers could position the head at release in, on average, nearly the identical position as at initiation.
- Removal of the helmet and shoulder pads resulted in a drop in linear and angular head position, placing the cervical spine into increased extension.
40.
Maria Angela Guzzardi Leanne Hodson Letizia Guiducci Elena Sanguinetti Pietro Di Cecco Tiziana Liistro Cristina Vassalle Silvia Pardini Lucia Giorgetti Piero A. Salvadori Silvia Burchielli Patricia Iozzo 《Diabetologia》2014,57(9):1937-1946