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991.
Progressive multifocal leukoencephalopathy is a fatal demyelinating disorder due to human polyomavirus JC infection in which there are viral inclusions in enlarged nuclei of infected oligodendrocytes. We report that the pathogenesis of this disease is associated with distinct subnuclear structures known as promyelocytic leukemia nuclear bodies (PML-NBs). Postmortem brain tissues from 5 patients with the disease were examined. Affected cells with enlarged nuclei contained distinct dot-like subnuclear PML-NBs that were immunopositive for PML protein and nuclear body protein Sp100. Major and minor viral capsid proteins and proliferating cell nuclear antigen, an essential component for DNA replication, colocalized with PML-NBs. By in situ hybridization, viral genomic DNA showed dot-like nuclear accumulation, and by electron microscopy, virus-like structures clustered in subnuclear domains, indicating that PML-NBs are the site of viral DNA replication and capsid assembly. Molecules involved in the ubiquitin proteosome pathway (i.e. ubiquitin and small ubiquitin-like modifier 1) did not accumulate in the nuclei with viral inclusions, indicating that cell degeneration may not be dependent on this pathway. When viral progeny production was advanced, PML-NBs were disrupted. These data suggest that: 1) PML-NBs allow for efficient viral propagation by providing scaffolds, 2) disruption of PML-NBs is independent of the ubiquitin-proteasome pathway, and 3) this disruption probably heralds oligodendrocyte degeneration and the resulting demyelination.  相似文献   
992.
993.
Recent outcome of Graves' disease patients with papillary thyroid cancer   总被引:1,自引:0,他引:1  
OBJECTIVE: The objective was to evaluate the clinical behavior and outcome of 202 papillary thyroid cancers in Graves' disease patients during the period 1994-2004. DESIGN: This was a retrospective, non-randomized case-control study. METHODS: Since 1994, we have included an ultrasonogram of the neck in the initial examination of thyroid disease patients who consult our outpatient clinic. We evaluated the tumor status and long-term outcome of Graves' disease patients with thyroid cancer and of age- and tumor size-matched euthyroid papillary thyroid cancer patients as controls. Serum TSH receptor antibody (TRAb) was measured in the Graves' disease group. RESULTS: A total of 154 papillary thyroid cancers were diagnosed in the Graves' disease patients and were treated surgically. At surgery, no significant differences in multifocality, lymph node metastasis, or distant metastasis were found between the Graves' disease group and the euthyroid group. On the whole, the clinical course of the cancers in both the Graves' disease group and euthyroid group was relatively good. No significant correlations were found between the TRAb levels in the Graves' disease group and multifocality or the presence of lymph node metastasis. Papillary thyroid cancer was discovered as an incidental finding in 2% of the 2356 surgically treated Graves' disease patients, but none of them developed metastasis during the follow-up period. CONCLUSION: The results in this series of patients do not support the claim that thyroid cancer is more aggressive in Graves' disease patients than in euthyroid patients.  相似文献   
994.
995.
X-linked lissencephaly with absent corpus callosum and abnormal genitalia (XLAG) is caused by a mutation in the ARX gene. We herein report the clinical course of siblings with XLAG with a splicing mutation in ARX. Seizures were observed in utero. Cerebral atrophy was progressive postnatally, and fetal echoencephalography indicated that the atrophy might have started in the prenatal period. They had a typical phenotype, except that the genital abnormality of the younger brother was not remarkable. A portal-systemic shunt that has not been reported in cases with XLAG was seen in the older brother. The siblings had the different complications and severity of disease in spite of possessing the same mutation.  相似文献   
996.
A 60-year-old man was diagnosed with asymptomatic T-cell granular lymphocyte (T-LGL) leukemia in September 2006. He was serologically positive for human T-cell leukemia virus type 1 (HTLV-1). However, monoclonal integration of the HTLV-1 genome was not detected in the peripheral blood, suggesting that HTLV-1 did not contribute to the pathogenesis of T-LGL leukemia in the present case. Phenotypically, neoplastic cells of our case were CD3+, CD4*, CD8+, CD16-, CD56+, CD57*, and T-cell receptor (TCR) alphabeta+. They also coexpressed CD20 antigen with weak intensity. This represented a unique case of T-LGL leukemia showing a typical clinical and phenotypic features.  相似文献   
997.
The association of P300 components with age, illness duration and gender were examined in schizophrenia patients and whether such variables indicate a progressive course. A total of 60 patients with schizophrenia and 70 healthy controls were studied utilizing standard auditory oddball tasks. Both healthy and schizophrenia groups had a significant positive correlation between age and P300 latency. There was also a significant positive correlation between illness duration and P300 latency in the schizophrenia group. The prolonged latency of P300, associated with age or illness duration, was more prominent in male than female schizophrenia subjects. These findings suggest gender differences in disease progression in schizophrenia.  相似文献   
998.
Angiogenesis is required for tumor growth and metastasis and, therefore, represents a target for cancer treatment. While many factors have been implicated in promoting angiogenesis, vascular endothelial growth factor (VEGF) plays a key role in tumor angiogenesis. ZD6474 is a potent VEGF receptor-2 (VEGFR-2) tyrosine kinase inhibitor which also has activity against the epidermal growth factor receptor (EGFR) tyrosine kinase. The purpose of this study was to investigate the sensitivity of head and neck squamous cell carcinoma (HNSCC) cell lines to ZD6474, and to evaluate its antitumor efficacy on HNSCC xenografts. This is the first demonstration of antitumor effects of ZD6474 on HNSCC. In vitro ZD6474 displayed antiproliferative effects on HNSCC cells and inhibition of VEGFR-2 and EGFR pathways. In vivo ZD6474 displayed antitumor activity, induced apoptosis and antiangiogenic activity on nude mice bearing an established xenograft of YCU-H891 cells. These results suggest that ZD6474 has the potential to inhibit two key pathways in tumor growth via inhibition of VEGF-dependent tumor angiogenesis and via inhibition of EGFR-dependent tumor cell proliferation.  相似文献   
999.
Human T-cell lymphotropic virus type 1 (HTLV-1) is an etiologic agent of adult T-cell leukemia/lymphoma (ATL). HTLV-1 is spread by cell-to-cell transmission via the gp46-197 region, Asp197 to Leu216, on the envelope protein gp46. In the present study, we revealed a positive correlation between the appearance of an antibody recognizing the gp46-197 region (anti-gp46-197 antibody) and the severity of ATL. The prevalence and titer of the anti-gp46-197 antibody were found to be elevated along with the progression of ATL. In serial samples obtained from a single patient, the anti-gp46-197 antibody was detected before treatment in acute phase, then diminished after allogeneic bone marrow transplantation, to which the patient had a complete response. However, the antibody appeared again before a relapse, along with an increase of the serum-soluble interleukin-2 receptor level and proviral load. The results from the other six patients also indicate that seroconversion of this antibody was synchronized with the deterioration of ATL. Taken together, the findings indicate that the anti-gp46-197 antibody may be a novel beacon for gauging the efficacy of therapeutic approaches to ATL, and a survey of this antibody would be useful for identifying asymptomatic carriers infected with HTLV-1 who are at high risk of developing ATL.  相似文献   
1000.
Background Paclitaxel often causes severe hypersensitivity reactions (HSRs) rapidly after infusion, even in patients given prophylactic therapy. The purpose of this study was to analyze the incidence of paclitaxel-related HSRs in patients with non-small cell lung cancer (NSCLC) retrospectively, and to assess the feasibility of a modified premedication protocol. Methods One hundred and seven patients who were pretreated with either a conventional premedication regimen (two doses of dexamethasone) or a short premedication regimen (single dose of dexamethasone with oral diphenhydramine and intravenous ranitidine), prior to paclitaxel infusion were retrospectively analyzed. A modified premedication regimen, consisting of 12.5 ml of Rescalmin (intravenous diphenhydramine 50 mg and calcium bromide 437.5 mg), intravenous ranitidine 100 mg, and intravenous dexamethasone 20 mg, was given 30 min prior to paclitaxel, with oral dexamethasone 8 mg given on the night before the paclitaxel. Patients received paclitaxel intravenously at 175 mg/m2 over 3 h, followed by carboplatin, AUC 5, over 1 h on day 1 every 3 weeks. Results In the conventional premedication group, 21 patients had HSRs (32.3%); in 1 of these patients the HSR was considered to be severe (1.5%). In the short premedication group, 19 patients had HSRs (45.2%); in 6 of these patients the HSRs were considered to be severe (14.3%). The incidence of severe HSRs was significantly higher in the short premedication group than in the conventional premedication group (P = 0.027). In the modified premedication protocol study, HSR events were recorded in 14 patients (63.6%); 14 showed flushing, 2 had skin rash, and 1 had tachycardia. No severe HSRs were seen. Conclusions The incidence of HSRs in the short premedication group tended to be higher than that in the conventional premedication group. The modified premedication protocol was found to be feasible for preventing paclitaxel-related HSR, but case accumulation is needed.  相似文献   
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