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61.
The WT1 tumor suppressor gene was examined for mutations in a panel of 44 patients with myelo-dysplastic syndromes (MDS) including acute myelogenous leukemias (AML) secondary to MDS, using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis and sequencing analysis. A WT1 mutation was detected in one out of 17 cases of AML secondary to MDS. This mutation exists upstream of the zinc finger region and is predicted to produce a truncated WT1 protein lacking the zinc finger region. No mutations were detected in 27 MDS patients who had not progressed to AML. This is the first report of analysis for WT1 mutations in a large number of MDS patients, suggesting that WT1 mutations are uncommon in MDS. Abnormalities in this gene may, however, contribute to a small proportion of cases showing progression from MDS into AML.  相似文献   
62.
Although exfoliative dermatitis (erythroderma) secondary to malignancy is commonly associated with lymphomas or leukemias, coincident gastrointestinal (GI) malignancy and erythroderma is rare. The authors recently encountered a patient with gallbladder carcinoma presenting as erythroderma. A 77-yr-old Japanese man presented with a 3-mo history of erythematous eruptions with pruritus over almost the entire body. After confirming the diagnosis of erythroderma, asymptomatic gallbladder carcinoma was found. Further investigations detected no malignancies in other organs. An extended cholecystectomy was performed. Histologic examination of resected specimens revealed poorly differentiated adenocarcinoma with negative resection margins. The eruptions with pruritus resolved within 1 wk after the operation. This is the first report, to our knowledge, of coincident biliary malignancy and erythroderma. The experience of the current patient suggests that erythroderma secondary to GI malignancy may resolve spontaneously after curative resection of the tumor.  相似文献   
63.
The antitumor 3'-ethynyl nucleosides, 1-(3-C-ethynyl-beta-D-ribopentofuranosyl)cytosine (ECyd) and 1-(3-C-ethynyl-beta-D-ribopentofuranosyl)uridine (EUrd), are potent inhibitors of RNA polymerases and show excellent antitumor activity against various human solid tumors in xenograft models. ECyd is being investigated in phase I clinical trials as a novel anticancer drug possessing a unique antitumor action. ECyd and EUrd require the activity of uridine/cytidine kinase (UCK) to produce the corresponding active metabolite. The UCK family consists of two members, UCK1 and UCK2, and both UCKs are expressed in many tumor cells. It was unclear, however, whether UCK1 or UCK2 is responsible for the phosphorylation of the 3'-ethynyl nucleosides. We therefore established cell lines that are highly resistant to the 3'-ethynyl nucleosides from human fibrosarcoma HT-1080 and gastric carcinoma NUGC-3. All the resistant cell lines showed a high cross-resistance to ECyd and EUrd. As a result of cDNA sequence analysis, we found that UCK2 mRNA expressed in EUrd-resistant HT-1080 cells has a 98-base pair deletion of exon 5, whereas EUrd-resistant NUGC-3 cells were harboring the point mutation at nucleotide position 484 (C to T) within exon 4 of UCK2 mRNA. This mutation was confirmed by genome sequence analysis of the UCK2 gene. Moreover, the expression of UCK2 protein was decreased in these resistant cells. In contrast, no mutation in the mRNA or differences in protein expression levels of UCK1 were shown in the EUrd-resistant HT-1080 and NUGC-3 cells. These results suggest that UCK2 is responsible for the phosphorylation and activation of the antitumor 3'-ethynyl nucleosides.  相似文献   
64.
BACKGROUND: Peripheral blood stem cell (PBSC) reinfusion has been widely used for hematopoietic reconstitution after high-dose chemotherapy. However, the optimal dose of granulocyte colony-stimulating factor (G-CSF) for PBSC mobilization in combination with chemotherapy for autograft remains unknown. METHODS: To find the optimal dose of glycosylated G-CSF (lenograstim) for PBSC mobilization in combination with chemotherapy for aggressive non-Hodgkin's lymphoma (NHL), we conducted a dose-finding study on 43 newly diagnosed patients who had unfavorable prognostic factors. They received four to six courses of cyclophosphamide, doxorubicin, vincristine and prednisolone combined with lenograstim every 2 weeks (biweekly CHOP therapy). PBSC apheresis was started after the third course of biweekly CHOP therapy. Lenograstim was given daily from day 3 until the day of the last apheresis. The optimum dose of lenograstim was assessed based on mobilization efficacy and safety profiles at a daily single dose of 2, 5 and 10 microg/kg for eight patients in each level. RESULTS: The collected number of CD34+ cells in the first apheresis products was higher in the 5 microg/kg group than in the 2 microg/kg group (median, 4.22 x 10(6) vs 2.49 x 10(6) CD34+ cells/kg, P = 0.051). The highest dose of 10 microg/kg (median, 2.99 x 10(6) CD34+ cells/kg) failed to show a dose dependence in PBSC mobilization. The efficacy and safety of the 5 microg/kg dose were further confirmed in an additional 19 patients. CONCLUSIONS: The present study suggests that the recommended dose of lenograstim for PBSC mobilization with CHOP therapy in untreated NHL is 5 microg/kg.  相似文献   
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67.
PURPOSE: It may be worthwhile to assess the possible protective effect of the traditional Japanese diet on allergic disorders. This cross-sectional study investigated the relationship between dietary intake of seaweed, vegetables, fruit, antioxidants, fiber, and minerals and the prevalence of allergic rhinitis. METHODS: Study subjects were 1002 Japanese pregnant women. Allergic rhinitis (including cedar pollinosis) was defined as present if subjects had received drug treatment at some point during the previous 12 months. Information on dietary factors was collected by using a self-administered diet history questionnaire. RESULTS: Seaweed intake was associated independently with a decreased prevalence of allergic rhinitis. Significant inverse dose-response relationships were found between calcium and phosphorus intake and allergic rhinitis prevalence. There also was a tendency for an inverse association between magnesium consumption and allergic rhinitis. Additional adjustment for calcium or magnesium intake apparently did not influence the inverse association with seaweed consumption. Consumption of vegetables, fruit, vitamins C and E, fiber, and zinc showed no association with allergic rhinitis, whereas a significant positive relationship was observed between beta-carotene intake and allergic rhinitis. CONCLUSIONS: High dietary intake of seaweed, calcium, magnesium, and phosphorus may be associated with a decreased prevalence of allergic rhinitis.  相似文献   
68.
A 64-year-old man in a severely immunocompromised state due to acute myelogenous leukemia died, respirator-unaided, about 10 h after the abrupt onset of coma. An earlier blood culture had yielded Bacillus cereus. The autopsy, performed 2 h after death, demonstrated diffuse subarachnoid hemorrhage without berry aneurysms, and the formalin-fixed brain was tinged with gray-brownish discoloration. The sections of the brain presented a whitish tint of the surface layer of all portion of the cerebral cortices, even those in the sulci. Histological examination of the brain revealed leptomeningeal B. cereus dissemination, and widespread necrosis of the leptomeninges and arachnoid vessels without inflammatory cell reaction. The grossly recognizable whitish surface layer of the cerebral cortex showed overt hyperchromatism, and contained neurons more degenerative than those located in the deeper cortical layer. The total absence of inflammatory reaction may be explained by a combination of the immunocompromised state of the patient and the character of B. cereus infection, which in itself induces little inflammatory reaction. The prominent lesions were confined to the cerebral surface layer and leptomeningeal tissue including the arachnoid vessels, which were all bathed in the cerebrospinal fluid, suggesting that some necrotizing toxins had been secreted into the fluid by the B. cereus. The necrosis of arachnoid vessels is thought to have in turn caused diffuse subarachnoid hemorrhage and marked disturbance of the cerebral blood flow, resulting in the terminal coma. Received: 4 April 1996 / Revised, accepted: 8 September 1996  相似文献   
69.
We previously reported that healthy adult males who consumed coix seeds for 1 week demonstrated an increased intestinal abundance of Faecalibacterium prausnitzii and altered peripheral lymphocyte subset percentages. However, the mechanism underlining these effects has not been elucidated. Therefore, cytokines and metabolites in plasma obtained in this study are comprehensively analyzed. A total of 56 cytokines and 52 metabolites in the plasma are quantified. Among them, 14 cytokines and 9 metabolites show significant changes in their levels following coix seed consumption. We examine the relationship between these changes and those in peripheral lymphocyte subset percentages and intestinal abundance of F. prausnitzii, which is also considerably altered following coix seed consumption. The galectin-9 concentration considerably decreased after coix seed consumption, and these changes correlate with those in cytotoxic T cells and pan T cells. Therefore, galectin-9 is possibly involved in the changes in peripheral lymphocyte subset percentages induced by coix seed consumption.  相似文献   
70.
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