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Spinocerebellar ataxia, autosomal recessive 2 (SCAR2) [MIM:213200] is a rare autosomal recessive disease of spinocerebellar ataxia associated with degeneration of the cerebellum with variable involvement of the brainstem and spinal cord. SCAR2 is characterized by onset of impaired motor development and ataxic gait in early childhood. Recently, several PMPCA gene variants have been reported in SCAR2 patients with mild and non-progressive symptoms. PMPCA codes frataxin, which is crucial for iron biosynthesis in cells. We report a case of a 15-year-old Japanese girl with infancy-onset, very severe and progressive developmental delay, cerebellar ataxia, and extrapyramidal symptoms. Brain magnetic resonance imaging showed cerebellar atrophy and excessive brain iron accumulation in the bilateral globus pallidi and substantia nigra. Based on the clinical phenotypes and imaging, neurodegeneration with brain iron accumulation was suspected. Whole-exome sequencing on the proband and her parents revealed novel compound heterozygous variants at c.667C > T (p.Arg223Cys) and c.853del (p.Asp285llefs*16) in PMPCA. Thus, her disease was diagnosed as SCAR2. Phenotype in our case was different from ones previously reported for SCARs in the points of much severer clinical presentations with extrapyramidal signs and imaging suspected iron accumulation, and might overlap neurodegeneration with brain iron accumulation or NBIA subtypes. Our case might provide a new insight into PMPCA gene-related disorders and expand the disease concept.  相似文献   
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Annals of Nuclear Medicine - This study aimed to determine the optimal β value of the relaxation control parameter and the post-smoothing filter in the list-mode dynamic row-action maximum...  相似文献   
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Status of endothelial dependent vasodilation in patients with hyperuricemia   总被引:7,自引:0,他引:7  
Hyperuricemia has been associated with an increased risk for cardiovascular disease and increased mortality. However, the biologic mechanisms that link elevated serum uric acid to cardiovascular disease are uncertain. This study tested the hypothesis that elevated serum uric acid is associated with impaired endothelial function in hyperuricemic patients without any overt cardiovascular disease. Seventeen male patients with hyperuricemia (mean age 42+/-4 years) and 9 control subjects (mean age 45+/-5 years) were studied. All subjects were nonsmokers. All patients had never been treated for hyperuricemia, were on no medications, and were free of any other known diseases. Endothelial function was evaluated by flow-mediated dilation measured by ultrasound. Flow-mediated dilation was significantly impaired in patients with hyperuricemia (4.0+/-0.7%) compared with control subjects (6.4+/-0.8%) (p=0.044). Flow-mediated dilation correlated inversely with uric acid levels (r=-0.4, p=0.05). Nitrate-induced dilation was 12.3+/-1.0% in patients with hyperuricemia and 11.8+/-2.3% in control subjects (p=0.82). Impaired endothelial-dependent vasodilation is present in hyperuricemic patients even in the absence of any overt cardiovascular disease. The elevated serum uric acid, per se, may constitute a novel risk factor for endothelial dysfunction.  相似文献   
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