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31.
This report describes a 67-year-old male with inoperable gastric cancer accompanied by marked tissue and peripheral eosinophilia without evidence of allergic disorders or parasitic infestation. Autopsy revealed an advanced gastric cancer of scirrhous type with metastases to pancreas, bone marrow, ileum, lungs, and lymph nodes. Excessive numbers of mature eosinophils were present in univolved bone marrow, liver and spleen as well as among the signet ring cell component of the cancer in either primary or metastatic sites. The primary cancer also possessed a component of tubular adenocarcinoma which was associated with only a few eosinophils. Hence, we speculate that an eosinophil mobilizing (chemotactic and/or proliferating) factor (s) was produced by the signet ring cancer cells. 相似文献
32.
Determination of bisphenol A concentrations in human biological fluids reveals significant early prenatal exposure 总被引:15,自引:0,他引:15
Ikezuki Y Tsutsumi O Takai Y Kamei Y Taketani Y 《Human reproduction (Oxford, England)》2002,17(11):2839-2841
BACKGROUND: There is broad human exposure to bisphenol A (BPA), an estrogenic endocrine-disrupting chemical widely used for the production of plastic products. BPA is reported to affect preimplantation embryos or fetuses and alter their postnatal development at doses typically found in the environment. We measured contamination of BPA in various kinds of human biological fluids by a novel enzyme-linked immunosorbent assay. METHODS: Blood samples were obtained from healthy premenopausal women, women with early and full-term pregnancy, and umbilical cord at full-term delivery. Ovarian follicular fluids obtained during IVF procedures and amniotic fluids obtained at mid-term and full-term pregnancy were also subject to BPA measurements. RESULTS: BPA was present in serum and follicular fluid at approximately 1-2 ng/ml, as well as in fetal serum and full-term amniotic fluid, confirming passage through the placenta. Surprisingly, an approximately 5-fold higher concentration, 8.3 +/- 8.7 ng/ml, was revealed in amniotic fluid at 15-18 weeks gestation, compared with other fluids. CONCLUSION: These results suggest accumulation of BPA in early fetuses and significant exposure during the prenatal period, which must be considered in evaluating the potential for human exposure to endocrine-disrupting chemicals. 相似文献
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34.
Tadao Tanimoto Shigeto Yamamoto Madoka Taniai Mutsuko Taniguchi Harumi Ariyasu Chie Ushio Miho Aga Yohei Mukai Yasuo Tsutsumi Toshio Ariyasu Tsunetaka Ohta Shigeharu Fukuda 《Journal of interferon & cytokine research》2007,27(6):517-523
Although there are at least 13 interferon-alpha (IFN-alpha) subtypes in humans, interactions between the subtypes remain unknown. To understand IFN-alpha interactions, we examined the antiproliferative activities and the receptor binding affinities of different combinations of IFN-alpha2 and IFN-alpha8 using six renal cell carcinoma (RCC) cell lines. Although IFN-alpha8 was the more potent subtype, synergistic and antagonistic antiproliferative effects were also observed in certain combinations of IFN-alpha2 and IFN-alpha8. To analyze the interactions between IFN-alpha2 and IFN-alpha8, the receptor-binding kinetics of different combinations of IFN-alpha2 and IFN- alpha8 to the IFN-alpha receptors, IFNAR-1 or IFNAR-2, were measured using a surface plasmon resonance-based biosensor. Unexpectedly, the receptor binding kinetics to IFNAR-2 but not to IFNAR-1 were mutually related to antiproliferative activity and increase in the binding speed (K(a)) for IFNAR-2. Moreover, we observed the increased fluorescence intensity (FI) of biotin-labeled IFN-alpha8 to IFNAR-2 by receptor binding inhibition assay with unlabeled IFN-alpha2 but not the other combinations. These findings indicate that the binding manner of IFN-alpha8 for IFNAR-2 is different from that of IFN-alpha2, suggesting that binding of IFN-alpha8 rather than binding of IFN-alpha2 to IFNAR-2 leads to activation and subsequent antiproliferative activity despite the same antiviral activity in RCC. 相似文献
35.
Ochiai H Ohtsu T Tsuda T Kagawa H Kawashita T Takao S Tsutsumi A Kawakami N 《Acta medica Okayama》2005,59(1):27-32
On February 13, 2002, a public health center in Hiroshima Prefecture, Japan, was notified that many individuals living at the Japan Maritime Self-Defence Force base had symptoms resembling those of food poisoning. Self-administered questionnaires requesting information regarding meal consumption and symptoms were distributed to all 281 members at the base. A case of the illness was defined as a member who had had watery or mucousy stool, or loose stool with abdominal cramps, more than twice a day after consuming dinner on February 12. Control of the illness was defined as a member with no symptoms. The dinner on February 12 was significantly associated with the illness (Mantel-Haenszel odds ratio: 3.59, 95% confidence interval: 1.06-12.20). A case-control study showed that, among the food supplied at dinner on February 12, the braised chop suey was significantly associated with the illness (odds ratio: 12.30, 95% confidence interval: 1.90-521.00). The braised chop suey had been stored in a chafing dish. An environmental investigation indicated that Clostridium perfringens (C. perfringens) in the chafing dish proliferated under an inappropriate heat-retention temperature, and the contaminated braised chop suey could have caused the food poisoning. This study demonstrated that the recommended heat-retention temperature (over 65 degrees C) should be confirmed thoroughly. 相似文献
36.
Aberrant transcription of FHIT gene in intrahepatic cholangiocellular carcinomas induced by N-nitrosobis(2-oxopropyl)amine in hamsters. 总被引:1,自引:0,他引:1
37.
The critical role of ocular-infiltrating macrophages in the development of choroidal neovascularization 总被引:9,自引:0,他引:9
Tsutsumi C Sonoda KH Egashira K Qiao H Hisatomi T Nakao S Ishibashi M Charo IF Sakamoto T Murata T Ishibashi T 《Journal of leukocyte biology》2003,74(1):25-32
Choroidal neovascularization (CNV) is directly related to visual loss in some eye diseases, such as age-related macular degeneration. Although several human histological studies have suggested the participation of macrophages in CNV formation, the precise mechanisms are still not fully understood. In this study, we elucidated the role of ocular-infiltrating macrophages in experimental CNV using CCR2 knockout (KO) mice, wild-type mice, and C57BL/6 (B6) mice. CCR2 is the receptor of monocyte chemoattractant protein-1, and the number of infiltrating macrophage and the area of CNV were significantly reduced in CCR2 KO mice. Enriched ocular-infiltrating macrophages from B6 mice actually showed angiogenic ability in a dorsal air sac assay. Moreover, their expression of class II, CD40, B7-1 and B7-2 molecules, and the mRNA for potential angiogenic factors, such as vascular endothelial growth factor, basic fibroblast growth factor, and tumor necrosis factor alpha, was also observed. Collectively, we conclude that ocular-infiltrating macrophages play an important role in CNV generation. 相似文献
38.
39.
Yoshio Mii Yoshizumi Miyauchi Kanya Hohnoki Hiroshi Maruyama Masahiro Tsutsumi Kayoko Dohmae Susumu Tamai Yoichi Konishi Takahisa Yamanouchi 《Virchows Archiv : an international journal of pathology》1989,415(1):51-60
Summary In order to clarify the histogenesis of clear cell sarcoma of tendons and aponeuroses (CCS), two cases of human and one nude mouse-transplanted CCS line were studied using an ultrastructural and enzyme cytochemical approach. Most of the tumour cells obtained from the primary and transplanted CCS demonstrated melanosomes in various stages of development within the cytoplasm, whereas no melanosomes could be identified in the metastatic CCS. However, cholinesterase and tyrosinase activities could be demonstrated not only in the melanotic primary and transplanted CCS but also in the amelanotic metastatic CCS. The results therefore support the hypothesis that CCS is a soft tissue tumour derived from the neural crest. 相似文献
40.
Kamoshida S Matsuoka H Shiogama K Matsuyama A Shimomura R Inada K Maruta M Tsutsumi Y 《Pathology international》2004,54(8):564-575
High expression of thymidylate synthase (TS) is allegedly associated with the chemoresistance to 5-fluorouracil (5-FU) in colorectal cancers. However, low TS expression does not necessarily imply chemosensitivity. Inactivation of p16(INK4a) correlates with poor prognosis in various cancers. We immunohistochemically evaluated the relationship between the expression of TS, p16(INK4a), CDK4 and cyclin D1 and the effect of 5-FU-based chemotherapy in colorectal cancers. After antigen retrieval, immunoperoxidase staining was performed on the paraffin-embedded, biopsy and surgical specimens of 37 advanced colorectal cancers preoperatively treated with peroral administration of 5-FU derivatives. As a control group, 31 colorectal cancers without preoperative treatment were analyzed. High TS expression was found in 23 (74%) of 31 tumors resected from histological non-responders and in 19 (61%) of 31 controls but in none of six responders. High p16(INK4a) expression was seen in 83% of the responders, 52% of the non-responders and 32% of the controls. The TS-low/p16(INK4a)-high phenotype was noted in 83% of the responders, but only in 3% of the non-responders (P = 0.0001). Induction of p16(INK4a) expression after chemotherapy was predominantly seen in the responders. Neither CDK4 nor cyclin D1 expression was related to the chemotherapeutic effects. In conclusion, the combination of low expression of TS and induction of p16(INK4a) after chemotherapy can be important indicators of the sensitivity to 5-FU-based chemotherapy in colorectal cancers. 相似文献