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21.
We present a suspicious case of central neurosarcoidosis that presented with progressive gait disturbance probably caused by central vestibular dysfunction. And this case showed elevated level of angiotensin converting enzyme (ACE) in the cerebrospinal fluid, compared with the average level of two cases with acute inflammatory demyelinating neuropathy syndrome and four cases of multiple sclerosis. A 33-year-old man was admitted to our hospital with chief complaint of a gait disturbance that had appeared 3 years prior to the admission. And the symptom had exacerbated in these 3 months. Except for the gait disturbance and positive Romberg's sign, no neurological abnormality was detected. The findings of the cerebrospinal fluid test supported the diagnosis of meningitis. An increased level of angiotensine converting enzyme was detected when compared with our previous samplings from two cases of Guillain Barré syndrome and four cases of multiple sclerosis. With T1 weighted imaging of brain MRI, a high intensity lesion with gadolinium enhancement was identified in the central gray matter of the midbrain. Scan of the chest confirmed bilateral hilar lymphadenopathy. Based on these findings and the patient's clinical course, central neurosarcoidosis was suspected. The patient's symptoms improved dramatically after the administration of corticosteroid. The enhancement of the central gray matter ameliorated, and the ACE level of the CSF was decreased to the level of the demyelinating disorders.  相似文献   
22.
We report a case of primary diffuse leptomeningeal gliomatosis (PDLG) followed up with serial magnetic resonance images (MRI). A 45‐year‐old man manifested with bilateral abducens nerve palsy and meningisms. Repeated MRI revealed diffuse leptomeningeal enhancement throughout the central nervous system without intra‐axial mass accompanied with the dilatation of ventricles and focally enlarged cerebral sulci. Brain biopsies showed a leptomeningeal gliomatosis. The MRI findings described here would contribute to the diagnosis of PDLG among other common diseases diffusely spreading along the leptomeningeal structures.  相似文献   
23.
The concentrations of oxidized coenzyme Q-10 (CoQ-10) and reduced CoQ-10 in the cerebrospinal fluid (CSF) of patients with Parkinson's disease (PD) was examined in order to determine whether the balance in oxidized and reduced CoQ-10 is related to the pathogenesis of PD. The percentage of oxidized/total CoQ-10 (%CoQ-10) in the CSF was significantly higher in the untreated PD group (80.3+/-17.9%) compared to the normal control group (68.2+/-20.4%) (p<0.05). The %CoQ-10 in the CSF of PD patients showed significant negative correlation with the duration of illness. These findings in living patients provide in vivo evidence for a possible role for %CoQ-10 in the pathogenesis in the early stages of PD development.  相似文献   
24.
Abstract: The possibility on placing electrodes at Fpz-A2 instead of C3-A2 was investigated to obtain a more stable configuration avoiding obstruction by the hair. Our original system of alpha wave detection by a microcomputer was used, and a total of 22 all-night hypnograms of five healthy young students waa recorded. Pearson's moment correlation coefficients of alpha wave % between the two positions were 0.780–0.948. Except for one subject, alpha wave % taken at Fpz-A2 tended to be 3–5% lower than that at C3-A2. The above analysis indicates that using EEG electrode position of Fpz-A2 is valid and useful as a stable electrode configuration for a long-time monitoring.  相似文献   
25.
1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N02? and N03? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iVG-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNOxV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide.  相似文献   
26.
Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity. Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers. On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes may also play an important role in damage to nerve fibers.  相似文献   
27.
28.
Collapsin response mediating protein-2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin-dependent kinase 5 (Cdk5) and glycogen synthase kinase 3beta (GSK3beta) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3beta did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3beta was exclusively observed in Cdk5-phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3beta secondarily phosphorylates at Thr509. The dual-phosphorylated CRMP2, but not non-phosphorylated or single-phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild-type but not cdk5-/- mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over-expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A-induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule-associated proteins.  相似文献   
29.
The concept of antiphospholipid syndrome(APS) has been widely accepted. Antiphospholipid antibodies originally included anticardiolipin antibodies and lupus anticoagulants as serological marker of APS. However, recent advances have shown that most pathogenic antiphospholipid antibodies are directed to phospholipid binding proteins such as beta 2-glycoprotein I and prothrombin as well as phospholipids. The preliminary classification criteria for definite APS have been advocated as the "Sapporo criteria". Further prospective investigations are required to re-evaluate the clinical significance of so-called antiphospholipid antibodies.  相似文献   
30.
We report on a boy with the blepharophimosis sequence and de novo, apparently balanced reciprocal translocation between 3q23 and 4p15.2 [46, XY,t(3;4)(q23;p15.2)de novo]. Possible assignment of this autosomal dominant disorder is discussed. A 3q23 band is a more preferable gene locus of the blepharophi mosis sequence, based on the comparison of clinical manifestations between 4p- and 3q-syndromes.  相似文献   
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