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31.
BackgroundOne in two people with multiple sclerosis (PwMS) will fall in a three-month period. Predicting which patients will fall remains a challenge for clinicians. Standardized functional assessments provide insight into balance deficits and fall risk but their use has been limited to supervised visits.Research questionThe study aim was to characterize unsupervised 30-second chair stand test (30CST) performance using accelerometer-derived metrics and assess its ability to classify fall status in PwMS compared to supervised 30CST.MethodsThirty-seven PwMS (21 fallers) performed instrumented supervised and unsupervised 30CSTs with a single wearable sensor on the thigh. In unsupervised conditions, participants performed bi-hourly 30CSTs and rated their balance confidence and fatigue over 48-hours. ROC analysis was used to classify fall status for 30CST performance.ResultsNon-fallers (p = 0.02) but not fallers (p = 0.23) differed in their average unsupervised 30CST performance (repetitions) compared to their supervised performance. The unsupervised maximum number of 30CST repetitions performed optimized ROC classification AUC (0.79), accuracy (78.4%) and specificity (90.0%) for fall status with an optimal cutoff of 17 repetitions.SignificanceBrief durations of instrumented unsupervised monitoring as an adjunct to routine clinical assessments could improve the ability for predicting fall risk and fluctuations in functional mobility in PwMS.  相似文献   
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《Injury》2023,54(8):110888
ObjectiveThis narrative review aims to investigate the effects of drugs on implant osseointegration, analyzing their potential positive or negative impact on the direct structural and functional connection between bone and load-carrying implants.BackgroundThe review seeks to provide a comprehensive understanding of osseointegration, which refers to the successful integration of an implant with living bone, resulting in no progressive relative movement between them. Exploring the effects of drugs on implant osseointegration is crucial for optimizing outcomes and enhancing patient care in orthopedic implant procedures.MethodsRelevant studies on the effects of drugs on implant osseointegration were identified through a literature search. Electronic databases, including PubMed, Embase, and Google Scholar, were utilized, employing appropriate keywords and MeSH terms related to osseointegration, implants, and drug interventions. The search was limited to English studies.DiscussionThis overview presents a detailed analysis of the effects of drugs on implant osseointegration. It explores drugs such as bisphosphonates, teriparatide, statins, angiotensin-converting enzyme inhibitors, beta-blockers, nitrites, and thiazide diuretics as promoters of osseointegration. Conversely, loop diuretics, non-steroidal anti-inflammatory drugs, corticosteroids, cyclosporine A, cisplatin, methotrexate, antibiotics, proton pump inhibitors (PPIs), antiepileptics, selective serotonin reuptake inhibitors (SSRIs), and anticoagulants are discussed as inhibitors of the process. The role of vitamin D3 remains uncertain. The complex relationship between drugs and the biology of implant osseointegration is emphasized, underscoring the need for further in vitro and in vivo studies to validate their effectsConclusionThis narrative review contributes to the literature by providing an overview of the effects of drugs on implant osseointegration. It highlights the complexity of the subject and emphasizes the necessity for more extensive and sophisticated studies in the future. Based on the synthesis of the reviewed literature, certain drugs, such as bisphosphonates and teriparatide, show potential for promoting implant osseointegration, while others, including loop diuretics and certain antibiotics, may impede the process. However, additional research is required to solidify these conclusions and effectively inform clinical practice.  相似文献   
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Provisional single drug-eluting stent (DES) strategy remains the standard of care in simple bifurcation lesions which comprise the vast majority of coronary bifurcations. Nevertheless, the presence of complex bifurcations which are defined based on the 1) Side Branch (SB) lesion length of >10 mm and 2) SB ostial diameter stenosis of >70% are approached with a 2-DES strategy upfront. The bifurcation angle will further define the most appropriate technique, with T-stenting more suitable in angulations close to 90°, Culotte and the family of Crush techniques more appropriate for acute angles of <75°. The Crush techniques which are composed of the classic Crush, mini-Crush and double kissing Crush (DK-Crush) share the core principle of protruding the SB DES within the Main Branch (MB) to minimize the risk of ostial SB restenosis, which remains the most prevalent etiology of stent failure during 2-stent approach in bifurcations. Proximal Side Optimization (PSO) is an additional technical consideration to further optimize the protruding SB struts enabling 1) optimal SB strut accommodation to the larger MB vessel diameter, 2) strut enlargement that will further facilitate effortless rewiring for kissing balloon inflation (KBI) avoiding unfavorable guide wire advancement in the peri-ostial SB area.  相似文献   
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ObjectiveCalcium pyrophosphate crystal deposition disease (CPPD) is a common cause of acute and chronic arthritis, especially in the elderly population. There is a paucity of data regarding the management of CPPD disease, which is currently based on expert opinion and evidence derived from the treatment of gout. We conducted a systematic literature review in order to identify the available treatment options for CPPD, and describe their efficacy and safety.Material and methodsOnline databases were searched from inception to May of 2020 using the search terms: (CPPD [Title/Abstract] OR CPDD [Title/Abstract] OR calcium pyrophosphate [Title/Abstract] OR chondrocalcinosis [Title/Abstract]) AND (treatment [Title/Abstract] OR management [Title/Abstract] OR therapy [Title/Abstract]). Articles evaluating the use of specific treatment agents for CPPD were eligible for inclusion. Case reports were excluded.ResultsA total of 22 eligible studies and 403 unique patients were selected. We identified only 3 randomized, double-blind, controlled trials (RCTs) evaluating the use of methotrexate, hydroxychloroquine, and magnesium carbonate in CPPD, and these therapeutic options, with the exception of methotrexate, have shown efficacy and reduction of pain intensity. Further, 10 case series and 9 cohort studies were included. Intramuscular and intra-articular glucocorticoids, ACTH, as well as the biologic agents anakinra and tocilizumab appear to be efficacious in CPPD. Intra-articular injections of glycosaminoglycan polysulphate, hyaluronic acid and yttrium, as well as synovial membrane destruction by laser irradiation were associated with symptomatic improvement. Due to significant study heterogenicity, direct comparison between studies was not possible.ConclusionThere are a limited number of studies evaluating the treatment of CPPD. High quality evidence is rather limited, while commonly administered agents such as NSAIDs, colchicine and corticosteroids have not been evaluated by RCTs. The need for high quality evidence supporting specific treatment modalities is urgent for this common yet neglected form of arthritis.  相似文献   
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The interpretation of medical images is a challenging task, often complicated by the presence of artifacts, occlusions, limited contrast and more. Most notable is the case of chest radiography, where there is a high inter-rater variability in the detection and classification of abnormalities. This is largely due to inconclusive evidence in the data or subjective definitions of disease appearance. An additional example is the classification of anatomical views based on 2D Ultrasound images. Often, the anatomical context captured in a frame is not sufficient to recognize the underlying anatomy. Current machine learning solutions for these problems are typically limited to providing probabilistic predictions, relying on the capacity of underlying models to adapt to limited information and the high degree of label noise. In practice, however, this leads to overconfident systems with poor generalization on unseen data. To account for this, we propose a system that learns not only the probabilistic estimate for classification, but also an explicit uncertainty measure which captures the confidence of the system in the predicted output. We argue that this approach is essential to account for the inherent ambiguity characteristic of medical images from different radiologic exams including computed radiography, ultrasonography and magnetic resonance imaging. In our experiments we demonstrate that sample rejection based on the predicted uncertainty can significantly improve the ROC-AUC for various tasks, e.g., by 8% to 0.91 with an expected rejection rate of under 25% for the classification of different abnormalities in chest radiographs. In addition, we show that using uncertainty-driven bootstrapping to filter the training data, one can achieve a significant increase in robustness and accuracy. Finally, we present a multi-reader study showing that the predictive uncertainty is indicative of reader errors.  相似文献   
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Cerebrotendinous xanthomatosis (CTX), sitosterolemia, and Smith-Lemli Opitz syndrome (SLOS) are rare inborn errors of metabolism. The diagnoses of CTX and sitosterolemia are often delayed for many years because of lack of physician awareness, often resulting in significant and unnecessary progression of disease. CTX may present with chronic diarrhea, juvenile onset cataracts, strikingly large xanthomas, and neurologic disease in the setting of a normal serum cholesterol, but markedly elevated serum or plasma cholestanol levels. These patients have a defect in producing the bile acid chenodoxycholate, and oral chenodeoxycholate therapy is essential for these patients in order to prevent neurologic complications. Sitosterolemia can present with xanthomas, anemia, thrombocytopenia, splenomegaly, very premature heart disease, and serum cholesterol levels that may be normal or elevated, along with marked elevations of plasma β-sitosterol. These patients have a defect causing overabsorption of β-sitosterol, and the treatment of choice is oral ezetimibe. SLOS presents with growth delay, intellectual disability, multiple structural anomalies, and low serum cholesterol levels, and the defect is reduced cholesterol production. Treatment consists of dietary cholesterol supplementation and oral bile acid therapy which raises serum cholesterol levels and may improve symptoms. The metabolic and genetic defects in these disorders have been defined. There is no one in our field that has contributed more to the diagnosis and treatment of these disorders than Gerald Salen, MD, who died in late 2020 at 85 years of age. He will be greatly missed by his family, friends, and colleagues from around the world.  相似文献   
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BackgroundThe success of surgical repairs rely on the effectiveness and integrity of the surgical knots used to secure the repair. The purpose of this study is to examine and compare the performance of the Nice knot, the modified Nice knot, and a commonly used combination of surgeons' and square knots with respect to cyclic loading and load-to-failure usiflueng a high-strength suture composed of ultra-high molecular weight polyethylene in the hands of experienced surgeons.MethodsTwo experienced surgeons threw 3 different knot types 9 times, consisting of the Nice knot, modified Nice knot, and a surgeon's knot utilizing Ultrabraid #2 sutures. Each knot was subject to cyclic loading and load to failure testing.FindingsBoth surgeons had similar displacement data for the surgeon's knot, while the identity of the surgeon impacted displacement for the Nice knot (p = 0.03) and the modified Nice knot (p = 0.0002). The load to failure for the modified Nice knot (p < 0.001) and the Nice knot (p = 0.001) were significantly impacted by the surgeon tying the knot, while the surgeon's knot was not. Specimens failed where the sutures passed through the loop at the “base” of the knot.InterpretationsThe strength and integrity of complex surgical knots are variable between surgeons. While the proposed Modified Nice Knot has a theoretical advantage because the half hitches reinforce the primary knot, in load to failure testing both the Modified Nice Knot and the Nice Knot failed where the suture passed through the loop in the primary knot.  相似文献   
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