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61.
We examined the clinical characteristics and prognosis in six patients with familial von Hippel-Lindau (VHL) disease and seven with sporadic hemangioblastomas. The expression of vascular endothelial growth factor (VEGF), p53 protein, and proliferative potential with Ki67 monoclonal antibody (MIB-1) was compared using immunohistochemical methods between sporadic and VHL disease-associated hemangioblastomas. Patients with sporadic CNS hemangioblastomas were treated by total removal of the tumors, and they had a good long-term prognosis without neurological deficits on recurrence. However, patients with familial VHL disease often had multiple hemangioblastomas in the CNS and visceral tumors. Even if total removal of CNS hemangioblastomas in patients with VHL disease was performed initially, small multiple hemangioblastomas recurred during long-term follow-up in areas remote from the primary region resected by surgery. All of the hemangioblastomas displayed extensive over-expression of VEGF protein, with moderate to marked proliferation of blood vessels. The MIB-1 indices showed low values of 0.8% as the mean, with a range of 0.03%–2.1% for all the hemangioblastomas. None of the hemangioblastomas expressed p53 protein. The hemangioblastomas in patients with VHL disease were multiple in the CNS and were combined with visceral tumors. Patients with VHL disease had a poor long-term prognosis, in contrast to those with sporadic hemangioblastomas. The immunohistochemical findings for VEGF protein, p53 protein, and MIB-1 did not differ signifi-cantly between the sporadic and VHL disease-associated hemangioblastomas.  相似文献   
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A Bacillus subtilis/microsome Rec-assay was improved by the introduction of a period for the test sample to interact with the bacteria before cultivation in a Monod tube. This method is called the “liquid B. subtilis/microsome Rec-assay method.” Evaluation of the Rec-assay is presented in terms of R50, S-probit, and RS, which were analyzed with computer programs developed on Probit theory and Target theory. Results could be classified into four categories: strong DNA damaging, DNA damaging, not DNA damaging, and reverse. Application of the Rec-assay to water samples from a night soil treatment plant showed that raw night soils contained a considerable amount of DNA-damaging substances. The amount of DNA-damaging substances in test samples was measured in terms of a new indicator, “Rec-volume.” After the biological treatment of nitrification and denitrification process, and the tertiary treatment of chemical coagulation and floatation for phosphorus removal, DNA-damaging substances were effectively reduced in the treated water. Following the tertiary treatment, ozonation was practiced for disinfection and color removal in this plant. Ozonation also showed effective reduction of DNA-damaging substances in the treated waters. In order to concentrate DNA-damaging substances in test samples, the adsorption method of XAD-2 and XAD-8 resins followed by ether and methanol extraction was employed.  相似文献   
64.
Involvement of the thyroid gland by Langerhans' cell histiocytosis is quite rare. We describe the case of a 58-year-old man referred for treatment of a progressively enlarging goitre. The trachea was severely stenotic and adjacent structures such as the left carotid vein and the thyroid cartilage were also involved. Central diabetes insipidus and severe combined immunodeficiency were associated. Although fine needle aspiration biopsy of the thyroid was initially interpreted as papillary carcinoma, anaplastic thyroid cancer was suspected. Treatment with prednisolone, doxorubicin and irradiation controlled the tracheal compression. A diagnosis of thyroid Langerhans' cell histiocytosis was finally made on the basis of the presence of Birbeck granules and CD1a and CD4 antigen in the thyroid tumour cells. Furthermore, positive staining for CD68 and lysozyme suggested that the tumour cells may have had the character of phagocytic cells in addition to their dendritic cell nature. This is the first case of thyroid involvement by malignant histicytosis of Langerhans' cell type with unusual phagocytic markers.  相似文献   
65.
Abstract: The effect of motor-response recovery after a nonresponse condition on the CNV was investigated in relation to the MPI in 53 healthy adults. The control CNV area before the nonresponse condition had an inverted-U relation to the extraversion score. At the recovery condition the inverted-U relation between the CNV area and the extraversion score shifted toward the lower extraversion score in those subjects who showed a shortened reaction time: i.e., the introverts, particularly the dysthymiacs, responded with the larger CNV area at the recovery condition than at the control condition. These results suggest that the dysthymiacs who possibly have obsession and depression are at a high arousal level and compel attention to a repetitive event as habituating.  相似文献   
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Vascular endothelial growth factor (VEGF) was reported to be a potent proangiogenic factor that plays a pivotal role in both physiological and pathological angiogenesis. M475271, 4-quinazolinamine, N-(2-chloro-5-methoxyphenyl)-6-methoxy-7-[(1-methyl-4-piperidinyl) methoxy]-(9Cl), is a new anilinoquinazoline derivative that showed selective inhibition of Src kinase activity and tumor growth in vivo. Here, we examined the effect of M475271 on VEGF-induced human umbilical vein endothelial cell (HUVEC) proliferation and migration and their intracellular mechanisms. Our findings showed that M475271 pretreatment resulted in a significant inhibition of VEGF-induced HUVEC proliferation, [(3)H]thymidine incorporation, and migration. M475271 inhibited VEGF-induced Flk-1 and Src phosphorylation and their association. Confocal laser microscopic examination confirmed the inhibitory effect of M475271 on VEGF-induced Flk-1/Src association. M475271 inhibited VEGF-induced extracellular signal-regulated kinase1/2 (ERK1/2) and p38 but not Akt activation in a concentration-dependent manner. M475271, PI3-K inhibitor, and p38 inhibitor inhibited VEGF-induced HUVEC proliferation and migration. However, a MEK1/2 inhibitor inhibited VEGF-induced proliferation but not migration. These findings suggest that M475271 attenuates VEGF-induced HUVEC proliferation and migration through the inhibition of signaling pathways involving Src, ERK1/2, and/or p38. Taken together, these data indicate that M475271 may be a useful candidate for inhibition of endothelial cell proliferation and migration relevant to angiogenesis.  相似文献   
68.
OBJECTIVE: The objective of this study was to clarify the effects of mechanical stress on chondrocytes cultured in a tube. Centrifugal pressure was applied to chondrocytes cultured in a tube for 28 days, and the effect of this stress was evaluated using a molecular biological method. DESIGN: Articular cartilage was harvested from a rabbit. A cell suspension was then prepared, and transferred in 1 ml aliquots to polypropylene tubes. After 48 h of incubation, centrifugal pressure (6.9 MPa) was applied every 24 h. Changes in morphology, expression of messenger RNA (mRNA) for insulin-like growth factor-I (IGF-I) and type II collagen, cell number, wet weight and protein concentration were evaluated. RESULTS: Microscopically, formation of chondrocyte clusters was seen in the cultures subjected to stress. Ultrastructurally, collagen fibers were seen to run parallel to the cytoplasmic surface of the stressed chondrocytes. The peak of IGF-I mRNA expression was seen on day 5, whereas type II collagen mRNA expression peaked on day 14. Cell number, wet weight and protein concentration were significantly increased in the stressed cultures. CONCLUSIONS: These results suggest that mechanical stress might affect the arrangement of collagen fibers and the IGF-I activity of chondrocytes cultured in a tube, thus influencing chondrocyte proliferation and increasing the volume of the extracellular matrix. Furthermore, mechanical stress may also affect the metabolism of articular cartilage in vitro.  相似文献   
69.
BACKGROUND: Extracapsular spread of lymph node metastasis has been shown as a negative prognostic factor in cancers of several other organs. This study was performed to clarify the prognostic significance of extracapsular spread in patients receiving curative resection for gastric cancer. METHODS: Extracapsular spread was defined as infiltration of cancer cells beyond the capsule of the metastatic lymph node. Four hundred and two patients who underwent curative gastrectomy were evaluated. Eight potential prognostic factors, including the International Union Against Cancer (Union International Contra la Cancrum; [UICC]) N stage and nodal status classified by the presence of lymph node metastasis or extracapsular spread, were examined. RESULTS: Three survival curves grouped by nodal status differed significantly, and prognosis of patients with extracapsular spread was significantly worse than for the other groups. Both UICC N stage ( P < .001) and nodal status ( P < .001) were significant prognostic factors by multivariate analysis. UICC N stages were subcategorized by nodal status, and survival was shown to be significantly worse in patients with extracapsular spread in the UICC N1 group ( P = .04). CONCLUSIONS: Extracapsular spread was a significant negative prognostic indicator on multivariate analysis, and may be useful in combination with UICC N stage. Extracapsular spread was regarded as an important indicator to refine the nodal staging system in gastric cancer.  相似文献   
70.
To identify mutagens formed in a model reaction of lipid peroxidation, linolenic acid methyl ester and hemin were reacted with dG. As a result, a 4-oxo-2-hexenal-dG adduct (dG*) was identified in the model reaction mixture. The 4-oxo-2-hexenal (4-OHE) showed mutagenic activity in the Salmonella typhimurium strains TA100 and TA104. After 4-OHE was orally administered to mice, dG, 4-OHE-dC- and 4-OHE-5-methyl-dC adducts were detected in esophageal, stomach and intestinal DNA. In the vapor phase released from the methyl linolenate-hemin model system, and in the smoke released during the broiling of fish, 4-OHE was detected by GCMS. The 4-OHE seems to be produced by the auto-oxidation of omega-3 polyunsaturated fatty acids. These results provide a warning to workers dealing with omega-3 fats, who may be exposed to this volatile mutagen.  相似文献   
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