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81.
This is the first report of a patient with venous insufficiency following compressive arachnoiditis ossificans (AO). Symptoms of fluctuating monoplegia and sensory disturbance appeared monthly, lasting several weeks each time. Spinal magnetic resonance imaging (MRI) showed high T2-weighted signal intensity in the posterior portion of the column from T11 to T12 and an intradural lesion with low T2-weighted signal intensity. Neurological function and MRI improved markedly following an operation on AO. The symptoms seen in the present case were due to posterior venous insufficiency following compressive AO.  相似文献   
82.
The present study was designed to determine if the mood stabilizers, lithium and valproate, have common effects on concentrations of amino acid neurotransmitters which may be related to their mechanisms of action. Two separate groups of rats were administered therapeutic doses of lithium, sodium valproate, or saline for 2 weeks. Whole brain extracts were then examined using either high-field 1H NMR spectroscopy or HPLC. Both drugs decreased whole brain concentrations of aspartate, glutamate, and taurine while brain concentrations of gamma-aminobutyric acid (GABA) and alanine decreased following chronic sodium valproate administration but not following chronic lithium administration. These findings indicate that lithium and sodium valproate share common effects on the concentrations of certain amino acid neurotransmitters in whole brain which may be related to their mechanisms of action in bipolar disorder.  相似文献   
83.
To clarify the role of the Fas-Fas ligand (FasL) system in the peripheral blood from patients with various renal diseases, the Fas and FasL expression on mononuclear cells (MNCs) and serum levels of soluble Fas (sFas) and soluble FasL were investigated. Patients were selected from those with various types of glomerular diseases showing various degrees of renal function. Fas expression on MNCs was analyzed by a FACScan, sFas and soluble FasL were measured with an ELISA kit, and FasL expression on MNCs was counted using a FACScan after a bioassay. Fas-positive MNCs and sFas increased with statistical significance concomitantly with deterioration in renal function. Moreover, there was a significant correlation between them. sFas- and FasL-positive MNCs were significantly correlated with proteinuria. However, the Fas expression percentage on MNCs and/or serum levels of sFas did not correlate with the number of TUNEL-positive cells in the glomeruli. Also, there was no disease specificity in the activation of Fas. These results indicate that Fas expression on MNCs is activated in accordance with the deterioration in renal function without disease specificity, corresponding to the elevation of serum sFas levels to protect against Fas-mediated apoptosis.  相似文献   
84.
Activated STAT1 suppresses proliferation of cultured rat mesangial cells   总被引:2,自引:0,他引:2  
BACKGROUND: JAK-STAT signaling has been shown to promote development and proliferation in lymphopoietic and hematopoietic lineages. We investigated the effect of activated STAT1 on mesangial cell proliferation. METHODS: Rat mesangial cells of primary culture (rMCs) were used in the following experiments: (1) Whole cell lysates were immunoblotted against JAK1 and JAK2. (2) Whole cell lysates and nuclear proteins were extracted from rMCs with or without treatment with interferon-gamma, and immunoblotting was performed against both STAT1 and tyrosine (701)-phosphorylated STAT1. (3) rMCs and rMCs electroporated with either wild-type STAT1, mutated STAT1, or antibody against STAT1 were incubated with interferon-gamma for 20 hours, followed by a further incubation with [3H]-thymidine for four hours. RESULTS: JAK1, JAK2, and STAT1 were detected in whole cell lysates, suggesting that JAK-STAT signaling could be activated by interferon-gamma (INF-gamma). Using an antibody specific for tyrosine-phosphorylated STAT1, we detected signal in the INF-gamma-treated nuclear extracts, which showed translocation of phosphorylated STAT1 to the nucleus. [3H]-thymidine incorporation in the presence of INF-gamma was significantly lower than that of control in a dose-dependent manner. The introduction of wild-type STAT1 enhanced the effect of interferon-gamma and decreased [3H]-thymidine incorporation, whereas tyrosine-mutated (Y701F) STAT1 and SH2 domain (R602T)-mutated STAT1 reversed INF-gamma-induced suppression of [3H]-thymidine incorporation. Electroinjected antibody against STAT1 increased [3H]-thymidine incorporation upon stimulation with INF-gamma. CONCLUSION: STAT1 activated by interferon-gamma suppresses mesangial cell proliferation.  相似文献   
85.
To evaluate cytological changes of urothelial cells with intravesical instillation therapy of the bacillus Calmette-Guérin (BCG), cytological specimens of voided urine from patients with superficial bladder cancer (pTa and pT1) treated with intravesical BCG therapy were examined. The following three groups of patients who had no evidence of recurrence more than 2 years after the treatment were studied: groups 1 and 2, patients who were treated with BCG (n = 22) and epirubicin, a derivative of doxorubicin (n = 22), respectively, for prophylaxis of intravesical recurrence after transurethral resection (TUR); and group 3, patients receiving no intravesical therapy after TUR (n = 12). Sixteen cytological characteristics were studied before and after the treatment in each group. In group 1 patients translucent nuclei and prominent nucleoli, vacuolization of cytoplasm, and eosinophilic cytoplasmic inclusions were frequently observed in urothelial cells as well as an increase in granulocytes, especially within 3 months after BCG instillation therapy. In group 2 patients an increased nuclear/cytoplasmic ratio, hyperchromatic nuclei and prominent nucleoli of urothelial cells were transiently found within 1-2 months after intravesical epirubicin therapy. In group 3, translucent nuclei and prominent nucleoli of urothelial cells were found within 1-2 months after TUR. In conclusion, cytological changes induced by BCG therapy are nonspecific and reactive in nature, different from those due to chemotherapeutic agents and distinguishable from malignant changes of urothelial cells.  相似文献   
86.
Tissue oxygen pressure during prolonged ischemia of the liver   总被引:2,自引:0,他引:2  
BACKGROUND: The potential role of hepatovenous back-perfusion in maintaining organ viability of the inflow-occluded liver has been reported with respect to aspects of tissue perfusion and energy metabolism. In the present study, the physiological differences between liver ischemia induced by portal triad clamping (PTC) and that induced by total hepatic vascular exclusion (THVE) were investigated in a porcine disease model, with special reference to changes in tissue oxygen pressure (PtO(2)) of the liver. MATERIALS AND METHODS: Twelve female pigs were used for induction of 60 min of normothermic liver ischemia. They were assigned to two groups: a PTC group (n = 6) and a THVE group (n = 6). PtO(2) was measured before, during, and after the ischemic period at two different points in the middle lobe: on the central side close to the hepatovenous confluence and on the peripheral side close to the gallbladder bed. RESULTS: Although central PtO(2) decreased during ischemia in both groups, PTC group values at 40 and 60 min of ischemia remained significantly higher than THVE group values (60 +/- 28 and 42 +/- 21 mmHg vs 11 +/- 5 and 13 +/- 3 mmHg, respectively; means +/- SD). Peripheral PtO(2) in the PTC group during ischemia was low in comparison to corresponding central PtO(2) values. CONCLUSION: Oxygen supply to the tissue via hepatovenous reflux may contribute to maintaining organ viability under prolonged inflow occlusion of the liver.  相似文献   
87.
We studied 867 junior high school children and administered a questionnaire documenting allergic symptoms and environmental variables, and measured Immunoglobulin E serum levels and the immunoglobulin G titers of serum antibody to microflora. A total of 716 subjects were ultimately used for statistics; those with at least two of the following allergic symptoms: asthma, rhinitis, eczema, or food allergy, showed significantly higher IgG titers to Bactroides vulgatus than other groups. This finding suggests that a species of the Bacteroides genus of the intestinal microflora tends to affect the gut issues, but further studies are needed to clarify this.  相似文献   
88.
Optic-spinal form of multiple sclerosis (OS-MS) and HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP) are two immune-mediated myelopathy relatively common in Japan. (1) Transverse myelitis, once seen in 60% of MS, mostly OS-MS, 30 years ago, drastically decreased (5%) recently in Japan. In contrast, frequency of conventional form of MS (C-MS) increased during this period of time. But unlike C-MS in white patients, cerebellar hemispheric lesions are uncommon in Japanese C-MS. These findings emphasize influence of changes in exogenous factors on manifestations of MS and distinct genetic factors related to MS in Japanese and white patients. (2) To clarify the reason of high HTLV-I proviral load in HAM/TSP, we studied cellular immune surveillance against HTLV-I and found that significant cytotoxic T lymphocyte activity, and suppressed natural killer activity and antibody-dependent cell-mediated cytotoxicity in the patients. These altered immune surveillance may be associated with the spread of HTLV-I infection and the pathogenesis of HAM/TSP.  相似文献   
89.
ObjectivesNo studies have examined the association between preterm birth rates and socioeconomic factors in Japan using nationwide statistical data. We analyzed the association between preterm birth rates and household occupation using Vital Statistics data.MethodsAggregated Vital Statistics data from Japan from 2007 to 2019 were obtained from the Ministry of Health, Labour and Welfare. From the data, the number of births according to year, age group, gestational period, number of pregnancies, and household occupation were used in this study. Crude preterm birth rates and preterm birth rates adjusted by maternal age according to household occupation were calculated for each year. Poisson regression analysis was conducted to evaluate the association between household occupation and preterm births.ResultsUnemployed households had the highest preterm birth rate, and households with an occupation classification of “full-time worker 2” (an employee at a large company, civil servant, or board member) had the lowest preterm birth rate throughout each period. Poisson regression analysis revealed that unemployed households were statistically significantly associated with a high preterm birth risk. In contrast, the preterm birth rate adjusted by maternal age remained stable throughout each period regardless of household occupation, and preterm birth rates were found not to have increased in recent years in Japan.ConclusionsUnemployed households had higher preterm birth rates than other household occupations. Further studies investigating the characteristics of unemployed households are needed to identify the reasons for this disparity.  相似文献   
90.
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