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Organ damage in sickle cell disease (SCD) is a crucial determinant for disease severity and prognosis. In a previous study, we analyzed the prevalence of SCD‐related organ damage and complications in adult sickle cell patients. We now describe a seven‐year follow‐up of this cohort.All patients from the primary analysis in 2006 (n = 104), were included for follow‐up. Patients were screened for SCD‐related organ damage and complications (microalbuminuria, renal failure, elevated tricuspid regurgitation flow velocity (TRV) (≥2.5 m/seconds), retinopathy, iron overload, cholelithiasis, avascular osteonecrosis, leg ulcers, acute chest syndrome (ACS), stroke, priapism and admissions for vaso‐occlusive crises (VOC) biannually. Upon 7 years of follow‐up, progression in the prevalence of avascular osteonecrosis (from 12.5% to 20.4%), renal failure (from 6.7% to 23.4%), retinopathy (from 39.7% to 53.8%) was observed in the whole group. In HbSS/HbSβ0‐thal patients also progression in microalbuminuria (from 34% to 45%) and elevated TRV (from 40% to 48%) was observed while hardly any progression in the prevalence of cholelithiasis, priapism, stroke or chronic ulcers was seen. The proportion of patients with at least one episode of ACS increased in the group of HbSS/HbSβ0‐thal patients from 32% to 49.1%. In conclusion, 62% of the sickle cell patients in this prospective cohort study developed a new SCD‐related complication in a comprehensive care setting within 7 years of follow‐up. Although the hospital admission rate for VOC remained stable, multiple forms of organ damage increased substantially. These observations underline the need for continued screening for organ damage in all adult patients with SCD.  相似文献   
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Fast cyclic movements and discrete motor acts are controlled differently, presumably because fast cyclic tasks are more automated, thereby depending on different circuits. If fast cyclic movements are made less predictable (e.g., by mixing frequencies), one would predict that their control will be less automated, requiring increased activity in motor cortical areas. The present functional near-infrared spectroscopy (fNIRS) study investigated whether switching between frequencies increases the motor cortex activity compared to movements at single rates. Therefore, hand tapping at mixed frequencies (“mixed”) was compared with hand tapping at 0.4 (“low frequency”), 0.8 (“mid-frequency”), and 1.4 Hz (“high frequency”). Oxy-hemoglobin (HbO) and deoxy-hemoglobin (HbR) concentration changes were studied in eleven healthy subjects with eight-channel fNIRS covering the hand motor cortex. Repeated-measures ANOVAs revealed significant main effects for the type of task in HbO and HbR. Post hoc analysis showed a larger HbO increase and HbR decrease for the mixed task compared to the low- and high-frequency conditions. In addition, the mid-frequency condition revealed a smaller HbR decrease compared to the mixed task. Single frequency data indicated the existence of separate motor control systems for low- and high-frequency movements. The increased activity for the mixed task is suggested to be the result of the recruitment of a voluntary command motor system instead of automated systems.  相似文献   
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Paroxysmal nocturnal hemoglobinuria, aplastic anemia, and myelodysplastic syndrome are a spectrum of acquired marrow failure, having a common pathologic thread of both immune dysregulation and the development of abnormal hematopoiesis. Allogeneic hematopoietic cell transplantation plays a critical role in the treatment of these disorders and, for many patients, is the only treatment modality with demonstrated curative potential. In recent years, there have been many breakthroughs in the understanding of the pathogenesis of these uncommon disorders. The subsequent advances in non-transplant therapies, along with concurrent improvement in outcomes after hematopoietic cell transplantation, necessitate continual appraisal of the indications, timing, and approaches to transplantation for acquired marrow failure syndromes. We review here contemporary and critical new findings driving current treatment decisions.  相似文献   
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