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Osteoporosis is a chronic condition that reflects reduced bone strength and an associated increased risk for fracture. As a chronic condition, osteoporosis generally requires sustained medical intervention(s) to limit the risks for additional bone loss, compromise of skeletal integrity, and fracture occurrence. Further complicating this issue is the fact that the abrupt cessation of some therapies can be associated with an increased risk for harm. It is in this context that the COVID-19 pandemic has brought unprecedented disruption to the provision of health care globally, including near universal requirements for social distancing. In this Perspective, we provide evidence, where available, regarding the general care of patients with osteoporosis in the COVID-19 era and provide clinical recommendations based primarily on expert opinion when data are absent. Particular emphasis is placed on the transition from parenteral osteoporosis therapies. It is hoped that these recommendations can be used to safely guide care for patients with osteoporosis until a return to routine clinical care standards is available. © 2020 American Society for Bone and Mineral Research.  相似文献   
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The need for renal replacement therapy is currently rising at an annually increasing rate. Current treatment options for patients with end-stage kidney disease include dialysis or organ transplantation. Yet, even though transplant survival has increased due to refined immunosuppressive therapy, morbidity remains high because of organ shortage. Here we discuss a recent publication that describes the transplantation of a bioengineered biocompatible kidney from a decellularized organ scaffold, thus possibly providing a solution to both transplant organ shortage and morbidity associated with long-term immunosuppression.  相似文献   
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Endothelial dysfunction begins in early CKD and contributes to cardiovascular mortality. HDL is considered antiatherogenic, but may have adverse vascular effects in cardiovascular disease, diabetes, and inflammatory conditions. The effect of renal failure on HDL properties is unknown. We studied the endothelial effects of HDL isolated from 82 children with CKD stages 2–5 (HDLCKD), who were free of underlying inflammatory diseases, diabetes, or active infections. Compared with HDL from healthy children, HDLCKD strongly inhibited nitric oxide production, promoted superoxide production, and increased vascular cell adhesion molecule-1 expression in human aortic endothelial cells, and reduced cholesterol efflux from macrophages. The effects on endothelial cells correlated with CKD grade, with the most profound changes induced by HDL from patients on dialysis, and partial recovery observed with HDL isolated after kidney transplantation. Furthermore, the in vitro effects on endothelial cells associated with increased aortic pulse wave velocity, carotid intima-media thickness, and circulating markers of endothelial dysfunction in patients. Symmetric dimethylarginine levels were increased in serum and fractions of HDL from children with CKD. In a longitudinal follow-up of eight children undergoing kidney transplantation, HDL-induced production of endothelial nitric oxide, superoxide, and vascular cell adhesion molecule-1 in vitro improved significantly at 3 months after transplantation, but did not reach normal levels. These results suggest that in children with CKD without concomitant disease affecting HDL function, HDL dysfunction begins in early CKD, progressing as renal function declines, and is partially reversed after kidney transplantation.Patients with CKD no longer die from renal failure but from cardiovascular disease. There is an independent, graded association between a reduced eGFR and the risk of death and cardiovascular events.1 Typically, patients with CKD develop calcification in the tunica media of their arteries,2 but a concomitant process of endothelial damage leading to atherosclerosis is also3 present beginning in predialysis CKD.4,5LDL is crucially involved in the pathogenesis of atherosclerotic cardiovascular disease in the general population,6 whereas HDL is thought to be antiatherogenic by promoting reverse cholesterol transport and exerting direct protective endothelial effects.7 HDL from healthy participants increases the bioavailability of nitric oxide (NO) by activating endothelial NO synthase inducing vasodilation and decreasing arterial BP. Moreover, HDL diminishes the production of reactive oxygen species such as superoxide (SO) radicals, which have been demonstrated to reduce NO bioavailability leading to endothelial dysfunction and promoting atherogenesis. However, recent evidence suggests that HDL may lose its vasoprotective properties in patients with manifest cardiovascular disease (e.g., coronary artery disease), diabetes, or inflammatory disease states (e.g., antiphospholipid syndrome).810 Similarly, in adults on dialysis, HDL has reduced cholesterol efflux capacity and proinflammatory effects on mononuclear cells.1113 Observational studies have shown a strong association between high HDL levels and reduced risk of cardiovascular disease in the general population14 but not in dialysis patients.15Cardiac and vascular damage has also been documented in children on dialysis,2,16,17 and cardiovascular disease accounts for the majority of deaths in pediatric dialysis patients.17 In contrast with adult patients with CKD, in whom cardiovascular risk factors such as diabetes dyslipidemia, hypertension, and smoking are highly prevalent,18 CKD in children is mainly caused by inherited disorders such as malformations of the kidney or urinary tract.18 Accordingly, examining HDL function in children who are free of “traditional” cardiovascular risk factors and underlying inflammatory diseases and who are nonsmokers gives us an unique opportunity to study the effects of renal failure on the vascular functions of HDL.We studied the endothelial properties of HDL in a cohort of children at different stages of CKD on dialysis and after transplantation and compared them with healthy children. Furthermore, to determine the clinical relevance of in vitro effects of HDL, we examined its relationship with clinical measures of the vascular phenotype as well as circulating markers of endothelial dysfunction. Finally, to show a causal link between renal function and HDL properties, we examined children on dialysis and 3 months after kidney transplantation. This study allowed us to examine when HDL dysfunction develops during the natural history of renal decline, its effects on vascular function, and the potential for recovery after kidney transplantation.  相似文献   
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Summary A voluntary insurance scheme for hospital care was launched in 1986 in the Bwamanda district in North West Zaire. The paper briefly reviews the rationale, design and implementation of the scheme and discusses its results and performance over time. The scheme succeeded in generating stable revenue for the hospital in a context where government intervention was virtually absent and external subsidies were most uncertain. Hospital data indicate that hospital services were used by a significantly higher proportion of insured patients than uninsured people. The features of the environment in which the insurance scheme thrived are discussed and the conditions that facilitated its development reviewed. These conditions comprise organizational-managerial, economic-financial, social and political factors. The Bwamanda case study illustrates the feasibility of health insurance — at least for hospital-based inpatient care - at rural district level in sub-Saharan Africa, but also exemplifies the managerial and social complexity of such financing mechanisms.  相似文献   
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