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991.
Seth D. Friedman PhD Sandra L. Poliachik PhD Randolph K. Otto MD Gregory T. Carter MD Christopher B. Budech BA Thomas D. Bird MD Daniel G. Miller MD PhD Dennis W.W. Shaw MD 《Muscle & nerve》2014,49(2):257-260
Introduction: Magnetic resonance imaging of muscle shows short tau‐inversion recovery (STIR) brightness in autosomal dominant facioscapulohumeral muscular dystrophy (FSHD1) suggestive of active inflammation/injury. We measured the longitudinal stability/progression of this potential disease biomarker. Methods: Nine subjects underwent calf MRI imaging over 2 years. Two radiologists evaluated qualitative muscle changes. Results: In 3/9 subjects, calf muscles demonstrated moderate/severe STIR hyperintensity at Time 1 that had progressed to fatty replacement 2 years later (Time 2). In the remaining subjects, moderate/severe muscle STIR abnormalities, when present, were consistent between exams. Mild STIR+ elevations had roughly similar patterns between exams. Conclusions: Moderate/severe STIR hyperintensities often foreshadow fatty replacement over a 2‐year interval. Whether longer time courses are required to observe muscle degeneration and fatty replacement in some subjects remains to be explored. Muscle Nerve 49 : 257–260, 2014 相似文献
992.
Sandra Perez da Rosa Christopher Paul Millward Muhammad Imran Bhatti Andrew Healey Sasha Clare Burn Ajay Sinha 《Child's nervous system》2014,30(5):891-895
Introduction
Cephalocele is a relatively rare cranial dysraphism characterised by herniation of intracranial structures through the skull. Surgical management is primarily necessary where a risk of infection through communication of the lesion with the intracranial space exists, a risk of rupture, or for cosmetic purposes. Cephalocele is often associated with venous anomalies such as vertical embryonic positioning of the straight sinus, splitting of the superior sagittal sinus, vein of Galen elongation, along with tenting of the tentorium [Morioka et al. Childs Nerv Syst 25:309–315, 2009]Patients
Here, we report four cases of cephalocele with pre-operative MRI imaging retrospectively studied, demonstrating associated venous anomalies. Three of these patients went on to have uncomplicated, corrective surgery, while one was managed conservatively.Results
All four cases demonstrated the main venous drainage going through a persistent falcine sinus to drain into the superior sagittal sinus. Upward tenting of the tentorium was observed in three cases (cases 1, 3 and 4). Two of our cases demonstrated other venous anomalies frequently reported in the literature, namely splitting of the superior sagittal sinus and absence of the transverse sinus (case 1) and communication of the cephalocele with the superior sagittal sinus and absence of the straight sinus (case 2).Conclusion
The association between cephalocele and venous anomalies suggests that pre-operative MRI should be mandatory for a full evaluation of a suspicious midline cranial lesion in order to evaluate the safety of corrective surgery. 相似文献993.
994.
Alessandra Carriero Elizabeth A Zimmermann Adriana Paluszny Simon Y Tang Hrishikesh Bale Bjorn Busse Tamara Alliston Galateia Kazakia Robert O Ritchie Sandra J Shefelbine 《Journal of bone and mineral research》2014,29(6):1392-1401
The multiscale hierarchical structure of bone is naturally optimized to resist fractures. In osteogenesis imperfecta, or brittle bone disease, genetic mutations affect the quality and/or quantity of collagen, dramatically increasing bone fracture risk. Here we reveal how the collagen defect results in bone fragility in a mouse model of osteogenesis imperfecta (oim), which has homotrimeric α1(I) collagen. At the molecular level, we attribute the loss in toughness to a decrease in the stabilizing enzymatic cross‐links and an increase in nonenzymatic cross‐links, which may break prematurely, inhibiting plasticity. At the tissue level, high vascular canal density reduces the stable crack growth, and extensive woven bone limits the crack‐deflection toughening during crack growth. This demonstrates how modifications at the bone molecular level have ramifications at larger length scales affecting the overall mechanical integrity of the bone; thus, treatment strategies have to address multiscale properties in order to regain bone toughness. In this regard, findings from the heterozygous oim bone, where defective as well as normal collagen are present, suggest that increasing the quantity of healthy collagen in these bones helps to recover toughness at the multiple length scales. © 2014 American Society for Bone and Mineral Research. 相似文献
995.
Cortical Porosity Identifies Women With Osteopenia at Increased Risk for Forearm Fractures
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Yohann Bala Roger Zebaze Ali Ghasem‐Zadeh Elizabeth J Atkinson Sandra Iuliano James M Peterson Shreyasee Amin Åshild Bjørnerem L Joseph Melton III Helena Johansson John A Kanis Sundeep Khosla Ego Seeman 《Journal of bone and mineral research》2014,29(6):1356-1362
Most fragility fractures arise among the many women with osteopenia, not the smaller number with osteoporosis at high risk for fracture. Thus, most women at risk for fracture assessed only by measuring areal bone mineral density (aBMD) will remain untreated. We measured cortical porosity and trabecular bone volume/total volume (BV/TV) of the ultradistal radius (UDR) using high‐resolution peripheral quantitative computed tomography, aBMD using densitometry, and 10‐year fracture probability using the country‐specific fracture risk assessment tool (FRAX) in 68 postmenopausal women with forearm fractures and 70 age‐matched community controls in Olmsted County, MN, USA. Women with forearm fractures had 0.4 standard deviations (SD) higher cortical porosity and 0.6 SD lower trabecular BV/TV. Compact‐appearing cortical porosity predicted fracture independent of aBMD; odds ratio (OR) = 1.92 (95% confidence interval [CI] 1.10–3.33). In women with osteoporosis at the UDR, cortical porosity did not distinguish those with fractures from those without because high porosity was present in 92% and 86% of each group, respectively. By contrast, in women with osteopenia at the UDR, high porosity of the compact‐appearing cortex conferred an OR for fracture of 4.00 (95% CI 1.15–13.90). In women with osteoporosis, porosity is captured by aBMD, so measuring UDR cortical porosity does not improve diagnostic sensitivity. However, in women with osteopenia, cortical porosity was associated with forearm fractures. © 2014 American Society for Bone and Mineral Research. 相似文献
996.
997.
998.
Sandra van Brunschot Paul Fockens Olaf J. Bakker Marc G. Besselink Rogier P. Voermans Jan-Werner Poley Hein G. Gooszen Marco Bruno Hjalmar C. van Santvoort 《Surgical endoscopy》2014,28(5):1425-1438
Objective
We performed a systematic review to assess the outcome of endoscopic transluminal necrosectomy in necrotising pancreatitis with additional focus on indication, disease severity, and methodological quality of studies.Design
We searched the literature published between January 2005 and June 2013. Cohorts, including patients with (infected) necrotising pancreatitis, undergoing endoscopic necrosectomy were included. Indication, disease severity, and methodological quality were described. The main outcomes were mortality, major complications, number of endoscopic sessions, and definitive successful treatment with endoscopic necrosectomy alone.Results
After screening 581 papers, 14 studies, including 455 patients, fulfilled the eligibility criteria. All included studies were retrospective analyses except for one randomized, controlled trial. Overall methodological quality was moderate to low (mean 5, range 2–9). Less than 50 % of studies reported on pre-procedural severity of disease: mean APACHE-II score before intervention was 8; organ failure was present in 23 % of patients; and infected necrosis in 57 % of patients. On average, four (range 1–23) endoscopic interventions were performed per patient. With endoscopic necrosectomy alone, definitive successful treatment was achieved in 81 % of patients. Mortality was 6 % (28/460 patients) and complications occurred in 36 % of patients. Bleeding was the most common complication.Conclusions
Endoscopic transluminal necrosectomy is an effective treatment for the majority of patients with necrotising pancreatitis with acceptable mortality and complication rates. It should be noted that methodological quality of the available studies is limited and that the combined patient population of endoscopically treated patients is only moderately ill. 相似文献999.
Steven Masson Benjamin Marrow Stuart Kendrick Ahmed M. Elsharkawy Sandra Latimer Mark Hudson 《Transplant international》2014,27(5):475-481
Return to drinking after liver transplantation for alcoholic liver disease (ALD) remains a source of unease with varying reported rates of return to drinking and impact this has on graft function. In 2005, the UK Transplant liver advisory group recommended an ‘alcohol contract’ in which ALD patients listed for transplantation confirmed in writing their commitment to abstinence. We aimed to measure the rates and consequences of return to drinking alcohol in a UK transplant programme and assess the effect of the ‘alcohol contract’. Consecutive patients transplanted for ALD during 1996–2011 were included. Every patient listed after Feb 2007 signed up to the ‘alcohol contract’. We compared rates and pattern of return to drinking and survival before and after the introduction of the contract. Overall, 52 (37%) patients returned to drinking alcohol; 37 (39%) before and 15 (34%) after the contract. There was no significant difference in the rate of return or pattern of drinking. Median survival was 176 months (145–207 95% CI). There was no significant difference in survival, mortality rates, or in the causes of death in either group. We report high rates of return to drinking alcohol in a UK liver transplant programme. Despite this, the impact on patient and graft survival is low. There is no evidence that an ‘alcohol contract’ has had any effect on alcohol consumption. 相似文献
1000.
Dieter P. Hoyer Anja Gallinat Sandra Swoboda Jeremias Wohlschläger Ursula Rauen Andreas Paul Thomas Minor 《Transplant international》2014,27(10):1097-1106
Machine perfusion for preservation led to compelling success for the outcome of renal transplantation. Further refinements of methods to decrease preservation injury remain an issue of high interest. This study investigates functional and morphological aspects of kidneys preserved by subnormothermic (20 °C) machine perfusion (SNTM) compared with oxygenated hypothermic machine perfusion (HMPox) and cold storage (CS) in a donation after circulatory death (DCD) model. After 30 min of warm ischaemia, porcine kidneys were randomly assigned to preservation for 7 h by CS, HMPox or SNTM. Afterwards, kidneys were reperfused for 2 h with autologous blood in vitro for assessment of function and integrity. Application of SNTM for preservation led to significantly higher blood flow and urine output compared with both other groups. SNTM led to a twofold increased creatinine clearance compared with HMPox and 10‐fold increased creatinine clearance compared with CS. Structural integrity was best preserved by SNTM. In conclusion, this is the first study on SNTM for kidneys from DCD donors. SNTM seems to be a promising preservation method with the potential to improve functional parameters of kidneys during reperfusion. 相似文献