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1.
Objective: Report measured resting energy expenditure (REE) in wheelchair rugby athletes and evaluate agreement between REE and the prediction models of Chun, Cunningham, Harris-Benedict, Mifflin, Nightingale and Gorgey, and Owen.

Design: Cohort-based validation study.

Setting. Paralympic team training camp.

Participants: Fourteen internationally competitive athletes who play wheelchair rugby, 13 of whom had cervical spinal cord injuries (SCI).

Outcome Measures: A portable metabolic analyzer was used to measure REE following an overnight fast and dual-energy X-ray absorptiometry (DXA) was used to assess lean body mass for the prediction equations.

Results: REE in the current sample was 1735?±?257?kcal?×?day?1 ranging from 1324 to 2068?kcal?×?day?1 Bhambhani Y. Physiology of wheelchair racing in athletes with spinal cord injury. Sports Med 2002;32(1):2351.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]. Bland–Altman analyses revealed negative mean bias but similar limits of agreement between measured REE and scores predicted by Chun, Cunningham, Mifflin, Nightingale and Gorgey, and Owen models in elite athletes who play wheelchair rugby.

Conclusion: Prediction models regressed on persons with and without SCI under-predicted REE of competitive wheelchair rugby athletes. This outcome may be explained by the higher REE/fat-free mass (FFM) ratio of current athletes compared to less active samples. Findings from the current study will help practitioners to determine nutrient intake needs on training days of varied intensity.  相似文献   
2.
Devices that are pinned to the tibia to tension an anterior cruciate ligament (ACL) graft produce joint reaction loads that in turn can affect the maintenance of graft initial tension after tibial fixation and hence knee anterior-posterior (AP) load-displacement. However, the effect of these devices on AP load-displacement is unknown. Our objectives were to determine whether tensioning by device versus tensioning by hand causes differences in AP load-displacement and intraarticular graft tension for two commonly used tibial fixation devices: a bioresorbable interference screw and a WasherLoc. AP load-displacement and intraarticular graft tension were measured in 20 cadaveric knees using a custom arthrometer. An initial tension of 110 N was applied to a double-looped tendon graft with the knee at extension using a tensioning device pinned to the tibia and a simulated method of tensioning by hand. After inserting the tibial fixation device, the 134 N anterior limit (i.e., anterior position of the tibia with respect to the femur with a 134 N anterior force applied to the tibia) and 0 N posterior limit (i.e., AP position of the tibia relative to the femur with a 0 N force applied to the tibia) were measured with the knee in 25 degrees flexion. Intraarticular graft tension was measured at extension. These limits and intraarticular graft tension were also measured after cyclically loading the knee 300 times. Compared to a simulated method of tensioning by hand, tensioning with a device pinned to the tibia did not decrease the 134 N anterior limit and did not cause posterior tibial translation. However, intraarticular graft tension was maintained better with a tensioning device pinned to the tibia for the Washerloc, but not the interference screw. For two commonly used tibial fixation devices, a tensioning device pinned to the tibia does not improve AP load-displacement at 25 degrees flexion over tensioning by hand when the graft is tensioned at full extension, but does improve the maintenance of intraarticular graft tension for the Washerloc.  相似文献   
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GAP-43 is normally produced by neurons during developmental growth and axonal regeneration, but it is also expressed in specific regions of the normal adult nervous system. We studied the protein expression of GAP-43 within the conus medullaris portion of the spinal cord in adult male rats. Immunohistochemistry for choline acetyltransferase (ChAT) was first performed to identify specific efferent autonomic and motor nuclei in lumbosacral segments of the spinal cord. Adjacent sections were then processed for GAP-43 immunoreactivity (IR). We show GAP-43 IR in the superficial portion of the dorsal horn, the intermediolateral nucleus, and the dorsal commissural tract. We also demonstrate a differential distribution of GAP-43 IR between different motor nuclei of the conus medullaris. Using densitometry, the most prominent GAP-43 IR was detected in the dorsolateral and dorsomedial motor nuclei, which represent the human Onufs nucleus homologue. Confocal microscopy of double immunofluorescent labeling for ChAT and GAP-43 demonstrate GAP-43 IR in the neuropil of the autonomic and motor nuclei, and many of the GAP-43 IR arbors are in close apposition with the efferent cholinergic neurons. We note that the efferent neurons of both the autonomic and somatic nuclei, which are ultimately responsible for the integrated normal control of the lower urinary tract, bowel and sexual functions, are heavily innervated by GAP-43 enriched projections. We speculate that these functionally related neurons retain a physiological GAP-43-associated synaptic plasticity throughout adult life.  相似文献   
4.
The mitotic chromosome movements are discussed in relation with recent studies on tubulins, their assembly and disassembly, and the associated proteins. The role of contractile proteins in the mitotic spindle is considered, and also that of the calcium regulating protein (CDR) which has been demonstrated recently in the mitotic spindle. The study of more "primitive" mitoses underlines the differences between polar and chromosomal MT. The linear growth of the first, and the sliding movements of MT from opposing poles, explain the growth in length of the mitotic figure and the separation of chromosomes. The complex relations between various types of MT and the possibility of biochemical varieties of tubulins, are discussed.  相似文献   
5.
Purpose of ReviewThe role of the meniscus in preserving the biomechanical function of the knee joint has been clearly defined. The hypothesis that meniscus root integrity is a prerequisite for meniscus function is supported by the development of progressive knee osteoarthritis (OA) following meniscus root tears (MRTs) treated either non-operatively or with meniscectomy. Consequently, there has been a resurgence of interest in the diagnosis and treatment of MRTs. This review examines the contemporary literature surrounding the natural history, clinical presentation, evaluation, preferred surgical repair technique and outcomes.Recent FindingsSurgeons must have a high index of suspicion in order to diagnose a MRT because of the nonspecific clinical presentation and difficult visualization on imaging. Compared with medial MRTs that commonly occur in middle age/older patients, lateral meniscus root injuries tend to occur in younger males with lower BMIs, less cartilage degeneration, and with concomitant ligament injury. Subchondral insufficiency fractures of the knee have been found to be associated with both MRTs and following arthroscopic procedures. Meniscus root repair has demonstrated good outcomes, and acute injuries with intact cartilage should be repaired. Cartilage degeneration, BMI, and malalignment are important considerations when choosing surgical candidates. Meniscus centralization has emerged as a viable adjunct strategy aimed at correcting meniscus extrusion.SummaryMeniscus root repair results in a decreased rate of OA and arthroplasty and is economically advantageous when compared with nonoperative treatment and partial meniscectomy. The transtibial pull-through technique with the addition of centralization for the medial meniscus is associated with encouraging early results.  相似文献   
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Context/Objective: Provisions of the Affordable Care Act (ACA) potentially increase insurance options for Veterans with disabilities. We examined Veterans with spinal cord injuries and disorders (SCI/D) to assess whether the ACA was associated with changes in healthcare utilization from Department of Veterans Affairs (VA) healthcare facilities.Design: Using national VA data, we investigated impacts on VA healthcare utilization pre- (2012/13) and post-ACA (2014/15) implementation with negative binomial regression models.Setting: VA healthcare facilities.Participants: 8,591 VA users with SCI/D. Veterans with acute myelitis, Guillain-Barré syndrome, multiple sclerosis, or amyotrophic lateral sclerosis were excluded as were patients who died during the study period.Interventions: We assessed VA healthcare utilization before and after ACA implementation.Outcome Measures: Total numbers of VA visits for SCI/D care, diagnostic care, primary care, specialty care, and mental health care, and VA admissions.Results: The number of VA admissions was 7% higher in the post than pre-ACA implementation period (P < 0.01). The number of VA visits post-implementation increased for SCI/D care (8%; P < 0.01) and specialty care (12%; P < 0.001). Conversely, the number of mental health visits was 17% lower in the post-ACA period (P < 0.001). Veterans with SCI/D who live <5 miles from their nearest VA facility received VA care more frequently than those ≥40 miles from VA (P < 0.001).Conclusion: Counter to expectations, results suggest that Veterans with SCI/D sought more frequent VA care after ACA implementation, indicating Veterans with SCI/D continue to utilize the lifelong, comprehensive care provided at VA.  相似文献   
8.
Antiphospholipid syndrome is a hypercoagulable disease that can present foot and ankle surgeons with a unique challenge in treating patients who present with thrombosis and ischemia despite having normal pedal pulses. Appropriate perioperative management is imperative in these patients, because limb- and life-threatening complications can occur postoperatively, despite aggressive anticoagulation. We present the case of a 46-year-old male who underwent a transmetatarsal amputation and, despite aggressive therapy, developed a myriad of complications postoperatively. At 10 months postoperatively, the patient was doing well in an accommodative orthotic with minimal pain while receiving continued aggressive therapy and follow-up examinations by a number of specialists to treat his antiphospholipid syndrome.  相似文献   
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