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Charcot-Marie-Tooth disease (CMT) comprises a heterogeneous group of hereditary motor and sensory peripheral neuropathies. The autosomal recessive axonal form of CMT (ARCMT2) is rare. Eight patients of a large consanguineous family of Spanish ancestry in Costa Rica were diagnosed with ARCMT2B; previous genetic studies of this family revealed linkage to chromosome 19q13.3. The clinical and electrophysiological features of these patients are reported. All patients presented with a symmetric motor and sensory neuropathy, which was more pronounced in the lower limbs. Further, distal muscle wasting and impaired deep tendon reflexes were found. Age at onset was between 26 and 42 years, and the disease duration ranged from 2 to 19 years. Electrophysiological studies revealed a primary axonal degenerative process. The clinical characteristics of this family differed in several aspects from previously reported families with ARCMT2.  相似文献   
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Flavonoids are an important group of recognized antioxidants ubiquitous in fruits, vegetables and herbs. There are epidemiological evidences for the stroke-protecting capacity of flavonoids and while the neuroprotective power of complex extracts rich in flavonoids like those of Ginkgo biloba, green tea or lyophilized red wine have been demonstrated in several studies, neuroprotection by individual flavonoids has been poorly studiedin vivo. The neuroprotective capacity of individual flavonoids was studied in PC12 cells in culture and in a model of permanent focal ischemia (permanent Middle Cerebral Artery Occlusion — pMCAO). In thein vivo experiments, flavonoids were administered in lecithin preparations to facilitate the crossing of the blood brain barrier.  相似文献   
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Eighteen children with severe head injuries and diffuse brain swelling were studied. They were separated into two groups based on the computed tomography (CT) findings. Seven patients had small ventricles in the normal location and small or absent cisterns. Eleven had these signs plus small deep-seated intraparenchymal hemorrhagic foci and/or intraventricular hemorrhage. Patients in the first group were in relatively good neurological condition; their intracranial pressure was easily controlled and all had a favourable outcome. On contrast, children in the second group had a more severe clinical presentation, frequently had uncontrollable intracranial hypertension, and more than 50% died.  相似文献   
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Prolonged inflammation and reactive oxygen species (ROS) generated around an implanted biosensor are the primary causes of the foreign body response, including encapsulation of biosensor membranes. We have previously demonstrated that TiO2 surfaces reduce ROS. Here we investigated the potential of using the anti-inflammatory properties of TiO2 in the design of biosensor membranes with improved long-term in vivo transport properties. Micropatterned Ti films were sputtered onto quartz surfaces in a series of hexagonally distributed dots with identical coverage area of 23% and dot size ranging from 5 to 100 microm. The antioxidant effect of the surfaces was investigated using a cell-free peroxynitrite donor assay and assays of superoxide released from stimulated surface-adhering neutrophils and macrophages. In all three assays, the amount of ROS was monitored using luminol-amplified chemiluminescence. Patterned surfaces in all experimental models significantly decreased ROS compared to the etched surfaces. In the cell-free experiment, the ROS reduction was only dependent on fractional surface coverage. In the cell experiments, however, a dot-size-dependent ROS reduction was seen, with the largest reduction at the smallest dot-size surfaces. These results indicate that micropatterned surfaces with small dots covering only 23% of the surface area exhibit similar antioxidative effect as fully covered surfaces.  相似文献   
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Background: Juvenile osteochondritis dissecans (OCD) has a better prognosis than the adult type. Objective: We postulated that the excellent prognosis of juvenile OCD could be explained, at least in part, by the erroneous diagnosis of some developmental variants of ossification as stage-I OCD. Materials and methods: Knee MRIs of 38 children, ages 7.5–17.7 years (mean and median age 13 years), were retrospectively reviewed to look for features that might separate normal variants of ossification from stage-I OCD. These included age, gender, site, configuration of the lesion, residual cartilaginous model and presence of edema. Results: Twenty-three patients (32 condyles) had ossification defects with intact articular cartilage suggestive of stage-I lesions. No stage-II lesions were seen in the posterior femoral condyles. Accessory ossification centers were seen in 11/16 posterior condyles and 3/16 central condyles. Spiculation of existing ossification was seen in 12/16 posterior condylar lesions and 1/16 central condyles. There was a predominance of accessory ossifications and spiculations in the patients with 10% or greater residual cartilaginous model. No edema signal greater than diaphyseal red-marrow signal was seen in the posterior condyles. Clinical follow-up ranged from 0.5 to 38 months, with clinical improvement in 22 out of 23 patients. Conclusion: Inclusion of normal variants in the stage-I OCD category might explain, in part, the marked difference in published outcome between the juvenile and adult forms of OCD. Ossification defects in the posterior femoral condyles with intact overlying articular cartilage, accessory ossification centers, spiculation, residual cartilaginous model, and lack of bone-marrow edema are features of developmental variants rather than OCD.  相似文献   
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