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41.
James L. Cook Aaron M. Stoker James P. Stannard Keiichi Kuroki Cristi R. Cook Ferris M. Pfeiffer Chantelle Bozynski Clark T. Hung 《Clinical orthopaedics and related research》2014,472(11):3404-3414
Background
Osteochondral allografting is an option for successful treatment of large articular cartilage defects. Use of osteochondral allografting is limited by graft availability, often because of loss of chondrocyte viability during storage.Questions/purposes
The purpose of this study was to compare osteochondral allografts implanted in canine knees after 28 days or 60 days of storage for (1) initial (1 week) safety and feasibility; (2) integrity and positioning with time (12 weeks and 6 months); and (3) gross, cell viability, histologic, biochemical, and biomechanical characteristics at an endpoint of 6 months.Methods
With Institutional Animal Care and Use Committee approval, adult dogs (n = 16) were implanted with 8-mm cylindrical osteochondral allografts in the lateral and medial femoral condyles of one knee. Osteochondral allografts preserved for 28 or 60 days using either the current tissue bank standard-of-care (SOC) or a novel system (The Missouri Osteochondral Allograft Preservation System, or MOPS) were used, creating four treatment groups: SOC 28-day, MOPS 28-day, SOC 60-day, and MOPS 60-day. Bacteriologic analysis of tissue culture and media were performed. Dogs were assessed by radiographs and arthroscopy at interim times and by gross, cell viability, histology, biochemistry, and biomechanical testing at the 6-month endpoint.Results
With the numbers available, there was no difference in infection frequency during storage (5% for SOC and 3% for MOPS; p = 0.5). No infected graft was implanted and no infections occurred in vivo. MOPS grafts had greater chondrocyte viability at Day 60 (90% versus 53%; p = 0.002). For 60-day storage, MOPS grafts were as good as or better than SOC grafts with respect to all outcome measures assessed 6 months after implantation.Conclusions
Donor chondrocyte viability is important for osteochondral allograft success. MOPS allows preservation of chondrocyte viability for up to 60 days at sufficient levels to result in successful outcomes in a canine model of large femoral condylar articular defects.Clinical Relevance
These findings provide a promising development in osteochondral allograft technology that can benefit the quantity of grafts available for use and the quality of grafts being implanted. 相似文献42.
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Maria Ferris Edward Iglesia Zion Ko Ahinee Amamoo John Mahan Tejas Desai 《Renal failure》2014,36(8):1340-1344
A workforce crisis for many pediatric specialties, particularly nephrology, is due to growing retirement rates, attrition during training, and retention difficulties. To obtain specific information regarding pediatric nephrology trainee shortages, we administered two cross-sectional surveys to non-renal pediatric subspecialty fellows and pediatric nephrology program directors. We characterized the fellows' experiences with nephrology and the program directors' experiences with their fellows as well as their outcomes in the last 10 years. We analyzed responses from 531 non-renal fellows (14.4% response rate). Overall, 317 (60%) fellows rated nephrology as difficult, particularly women (65.4% vs. 49.5%, p?0.001), with American women medical graduates rating nephrology as more difficult compared to all others (p?=?0.001). More men than women (24% vs. 8%, p?0.001) considered the monetary benefit as not adequate. Program directors (25; 64% response rate) represented 57% of all USA fellows in training, and 15 (60%) found it difficult to recruit qualified applicants. Of the 183 graduates in the past 10 years, 35 (19%) were reported as not in the USA pediatric nephrology workforce. These findings support our belief that a strong effort needs to be made by the academic community to teach nephrology in more interesting and understandable formats. While these are national samples, we were unable to contact non-nephrology fellows directly and program directors from larger programs were underrepresented. Difficulties in attracting/retaining trainees (particularly women) to nephrology must be addressed systematically, identifying incentives to practice in this field. Bold concerted efforts are required and we propose seven steps to achieve this goal. 相似文献
45.
Julieann C. Lee Javier E. Villanueva‐Meyer Sean P. Ferris Elaine M. Cham Jacob Zucker Tabitha Cooney Ahmed Gilani Bette K. Kleinschmidt‐DeMasters Dimitri Trembath Manuela Mafra Jason Chiang David W. Ellison Soo‐Jin Cho Andrew E. Horvai Jessica Van Ziffle Courtney Onodera Patrick Devine James P. Grenert Carmen M.A. de Voijs W.T. Marja van Blokland Wendy W.J. de Leng Marieke J. Ploegmakers Uta Flucke Melike Pekmezci Andrew W. Bollen Tarik Tihan Christian Koelsche Andreas von Deimling Pieter Wesseling David A. Solomon Arie Perry 《Brain pathology (Zurich, Switzerland)》2020,30(2):213-225
Desmoplastic small round cell tumors (DSRCTs) are highly aggressive sarcomas that most commonly occur intra‐abdominally, and are defined by EWSR1‐WT1 gene fusion. Intracranial DSRCTs are exceptionally rare with only seven previously reported fusion‐positive cases. Herein, we evaluate the clinical, morphologic, immunohistochemical and molecular features of five additional examples. All patients were male (age range 6–25 years; median 11 years), with four tumors located supratentorially and one within the posterior fossa. The histologic features were highly variable including small cell, embryonal, clear cell, rhabdoid, anaplastic and glioma‐like appearances. A prominent desmoplastic stroma was seen in only two cases. The mitotic index ranged from <1 to 12/10 HPF (median 5). While all tumors showed strong desmin positivity, epithelial markers such as EMA, CAM 5.2 and other keratins were strongly positive in only one, focally positive in two and negative in two cases. EWSR1‐WT1 gene fusion was present in all cases, with accompanying mutations in the TERT promoter or STAG2 gene in individual cases. Given the significant histologic diversity, in the absence of genetic evaluation these cases could easily be misinterpreted as other entities. Desmin immunostaining is a useful initial screening method for consideration of a DSRCT diagnosis, prompting confirmatory molecular testing. Demonstrating the presence of an EWSR1‐WT1 fusion provides a definitive diagnosis of DSRCT. Genome‐wide methylation profiles of intracranial DSRCTs matched those of extracranial DSRCTs. Thus, despite the occasionally unusual histologic features and immunoprofile, intracranial DSRCTs likely represent a similar, if not the same, entity as their soft tissue counterpart based on the shared fusion and methylation profiles. 相似文献
46.
Klaus Gramann Daniel P. Ferris Joseph Gwin Scott Makeig 《International journal of psychophysiology》2014
The primary function of the human brain is arguably to optimize the results of our motor actions in an ever-changing environment. Our cognitive processes and supporting brain dynamics are inherently coupled both to our environment and to our physical structure and actions. To investigate human cognition in its most natural forms demands imaging of brain activity while participants perform naturally motivated actions and interactions within a full three-dimensional environment. Transient, distributed brain activity patterns supporting spontaneous motor actions, performed in pursuit of naturally motivated goals, may involve any or all parts of cortex and must be precisely timed at a speed faster than the speed of thought and action. Hemodynamic imaging methods give information about brain dynamics on a much slower scale, and established techniques for imaging brain dynamics in all modalities forbid participants from making natural extensive movements so as to avoid intractable movement-related artifacts. To overcome these limitations, we are developing mobile brain/body imaging (MoBI) approaches to study natural human cognition. By synchronizing lightweight, high-density electroencephalographic (EEG) recording with recordings of participant sensory experience, body and eye movements, and other physiological measures, we can apply advanced data analysis techniques to the recorded signal ensemble. This MoBI approach enables the study of human brain dynamics accompanying active human cognition in its most natural forms. Results from our studies have provided new insights into the brain dynamics supporting natural cognition and can extend theories of human cognition and its evolutionary function — to optimize the results of our behavior to meet ever-changing goals, challenges, and opportunities. 相似文献
47.
Sara FL Kirk Mary Forhan Joshua Yusuf Ashly Chance Kathleen Burke Nicole Blinn Stephanie Quirke Ximena Ramos Salas Angela Alberga Shelly Russell-Mayhew 《AIMS Public Health》2022,9(1):41
BackgroundStigmatization of persons living with obesity is an important public health issue. In 2015, Obesity Canada adopted person-first language in all internal documentation produced by the organization, and, from 2017, required all authors to use person-first language in abstract submissions to Obesity Canada hosted conferences. The impact of this intentional shift in strategic focus is not known. Therefore, the aim of this study was to conduct a content analysis of proceedings at conferences hosted by Obesity Canada to identify whether or how constructs related to weight bias and obesity stigma have changed over time.MethodsOf 1790 abstracts accepted to conferences between 2008–2019, we excluded 353 abstracts that featured animal or cellular models, leaving 1437 abstracts that were reviewed for the presence of five constructs of interest and if they changed over time: 1) use of person-first versus use of disease-first terminology, 2) incorporation of lived experience of obesity, 3) weight bias and stigma, 4) aggressive or alarmist framing and 5) obesity framed as a modifiable risk factor versus as a disease. We calculated and analyzed through linear regression: 1) the overall frequency of use of each construct over time as a proportion of the total number of abstracts reviewed, and 2) the ratio of abstracts where the construct appeared at least once based on the total number of abstracts.ResultsWe found a significant positive correlation between use of person-first language in abstracts and time (R2 = 0.51, p < 0.01 for frequency, R2 = 0.65, p < 0.05 for ratio) and a corresponding negative correlation for the use of disease-first terminology (R2 = 0.48, p = 0.01 for frequency, R2 = 0.75, p < 0.001 for ratio). There was a significant positive correlation between mentions of weight bias and time (R2 = 0.53 and 0.57, p < 0.01 for frequency and ratio respectively).ConclusionUse of person-first language and attention to weight bias increased, while disease-first terminology decreased in accepted abstracts over the past 11 years since Obesity Canada began hosting conferences and particularly since more explicit actions for expectations to use person-first language were put in place in 2015 and 2017. 相似文献
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