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61.
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Background/Purpose: Recent studies have found that anomalous pancreaticobiliary ductal union (APBDU) is a substantial risk factor for biliary tract cancer at a younger age. DPC-4 (Smad-4) is a new tumor suppressor gene frequently inactivated in pancreatic and bile duct adenocarcinoma. To clarify carcinogenesis in APBDU, the authors investigated possible DPC-4 and K-ras mutations in 35 pediatric patients. Methods: DNA was extracted from biliary tract epithelial cells, which were resected surgically and histologically purified using microdissection. Polymerase chain reaction (PCR) primers were designed specifically for exons 8-11 of DPC-4 (18q21.1) and exons 1-2 of the K-ras oncogene (12p12.1). DNA sequences were determined using the direct DyeDeoxy Terminator Cycle method. Results: Of 35 children, 30 had wild-type DPC-4 and K-ras genes. K-ras mutations were detected in 5 patients, 4 of whom showed epithelial hyperplasia or metaplasia. In a 12-year-old girl with adenocarcinoma arising from a choledochal cyst, K-ras and DPC-4 (homozygous deletion) mutations were identified simultaneously. Conclusions: These results suggest that carcinogenesis in the biliary tract epithelium in APBDU is accompanied by multistep genetic mutational events; K-ras gene mutation occurs early in epithelial hyperplasia or metaplasia, whereas inactivation of the DPC-4 gene accumulates late in the progression of biliary tract adenocarcinoma. J pediatr Surg 38:694-697. [copy ] 2003 Elsevier Inc. All rights reserved. 相似文献
63.
Kawamoto K Nagano M Kanda F Chihara K Shigeyoshi Y Okamura H 《Journal of neuroscience research》2003,74(6):852-857
Vasoactive intestinal peptide (VIP) neurons constitute a large group in the suprachiasmatic nucleus (SCN) and it is thought that they are involved in the generation and entrainment of circadian rhythm. We have characterized these VIP-expressing neurons in rat SCN by their ability to induce the mammalian Period1 (Per1) gene in response to light exposure, innervation of retinal afferents, day-night variations in VIP mRNA, and coexpression of gastrin releasing peptide (GRP). VIP neurons in the ventrolateral SCN (SCNVL) were subdivided into two groups, light-evoked Per1-inducible main SCNVL (SCNVLmain) and non-Per1-inducible medially located SCNVL (SCNVLmed). Retinal innervation was abundant in the SCNVLmain but nearly absent in the SCNVLmed. Day-night variation in VIP mRNA expression level was observed in the SCNVLmain but not in the SCNVLmed. GRP mRNA was seen in rarely SCNVLmed but abundant in SCNVLmain, where some neurons coexpressed VIP mRNA. These findings indicate that VIP neurons in the SCN can be divided into two topographically and functionally distinct groups. 相似文献
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H. KOBAYASHI K. SUMIMOTO† N. MONIWA† M. IMAI‡ K. TAKAKURA‡ T. KUROMAKI‡ E. MORIOKA‡ K. ARISAWA‡ & T. TERAO† 《International journal of gynecological cancer》2007,17(1):37-43
Although some studies have indicated that endometriosis may increase the risk of developing ovarian cancer, there are no data from epidemiologic studies in Japan. We prospectively analyzed all cases of ovarian endometrioma enrolled in the prefecture-wide Shizuoka Cohort Study on Endometriosis and Ovarian Cancer Programme, which was initiated in 1985. To evaluate the risk of ovarian cancer by time periods subsequent to ovarian endometrioma diagnosis, a cohort of 6,398 women with a clinically documented ovarian endometrioma in Shizuoka between 1985 and 1995 was identified from the Shizuoka Cancer Registry (SCR), with follow-up through 2002. Ovarian cancer incidence among cohort members was ascertained by linkage to the SCR using a unique person-identification number. Standardized incidence ratios (SIR) and their 95% confidence intervals (CI) were computed by a use of prefecture-wide rates of ovarian cancer, adjusted for age and calendar year. During follow-up of up to 17 years of the ovarian endometrioma cohort, 46 incident ovarian cancers were identified, yielding that the ovarian cancer risk was elevated significantly among patients with ovarian endometrioma (SIR = 8.95, 95% CI = 4.12-15.3). The SIR did not increase with increasing follow-up duration. The risk increased with increasing age at ovarian endometrioma diagnosis, with a SIR equal to 13.2 (95% CI = 6.90-20.9) in women above 50 years of age. Our findings for the first time support the hypothesis that ovarian endometrioma increases the subsequent risk of developing ovarian cancer in Shizuoka, Japan. 相似文献
66.
T. SAKANO E. KITTAKA Y. TANAKA H. YAMAOKA Y. KOBAYASHI T. USUI 《Acta paediatrica (Oslo, Norway : 1992)》1980,69(4):549-551
Abstract. Sakano, T., Kittaka, E., Tanaka, Y., Yamaoka, H., Kobayashi, Y. and Usui, T. (Department of Paediatrics, Hiroshima University Hospital and Hiroshima City Hospital, Hiroshima, Japan). Vaccine-associated poliomyelitis in an infant with agammagiobulinemia. Acta Paediatr Scand, 69:549, 1980.—We describe a female infant with agammaglobulinemia who contracted vaccine-associated poliomyelitis. Poliovirus type 2 was isolated from the initial stool specimen. In our patient, temporary changes in the cerebrospinal fluid resembled those in patients without immunodeficiencies, although gammaglobulin therapy had not yet been started. Pleocytosis was observed for a short time after viremia, but soon there was a return to normal without antibody production. 相似文献
67.
MANABU OGISO MAKOTO TAKEHANA SHIZUKO KOBAYASHI MOTONORI HOSHI 《Experimental eye research》1998,66(6):765-773
Monkey and human lenses contain essentially the same glycosphingolipids, and Lewisxand sialylated Lewisxepitopes are expressed on the terminal structure of neolactotetraosylceramide. However, monolayer cultures of lens epithelial cells from rhesus monkey expressed gangliosides GM3, GD3 and a small amount of GM1, but not sialylated Lewisxepitopes. Eight-week-old cultures on various extracellular matrices resulted in morphological changes in lens epithelial cells. Monolayer of cells cultured on vitronectin or polylysine assembled into aggregates after 4 weeks of culture. Cells cultured on vitronectin expressed sialyl-Lewisxgangliosides and did not exhibit GD3. On collagens, fibronectin and laminin elongated cells were observed in cells cultured for 8 weeks. Thus, the interaction between cells and extracellular matrices influenced morphology and glycosphingolipid composition in lens epithelial cells. 相似文献
68.
Todo Shinjiro; Imashuku Shinsaku; Inoda Hiroshi; Yamanaka Hirofumi; Hibi Shigeyoshi; Tsunamoto Kentaro; Esumi Noriko; Fujiwara Fumihiro; Shimizu Yoshitaka; Morioka Yoshihito; Sugimoto Tohru 《Japanese journal of clinical oncology》1987,17(4):357-362
Severe hypercalcemia (serum calcium, 4.255.25 mmol/l),in association with osteolytic bone lesions, was found in agirl aged 2 yr 7 mo with common acute lymphoblastic leukemia(ALL). Hormonal studies excluded the possibility of the hypercalcemiabeing caused by primary hyperparathyroidism or ectopic parathyroidhormone secretion. Increased plasma prostaglandinE2 (PGE2).Jlevels (130 ng/l), probably produced by leukemic cells, wereconsidered to be one of the pathogenic mechanisms responsiblefor the occurrence of hypercalcemia in this patient. Both thehypercalcemia and the abnormal plasma PGE2 level returned tonormal after chemotherapy. 相似文献
69.
70.
In vivo glioma growth requires host-derived matrix metalloproteinase 2 for maintenance of angioarchitecture. 总被引:9,自引:0,他引:9
Megumi Takahashi Shinjiro Fukami Nobuhisa Iwata Keiichi Inoue Shigeyoshi Itohara Hiroshi Itoh Jo Haraoka Takaomi Saido 《Pharmacological research》2002,46(2):155-163
Glioma, the most common form of brain tumor, has been shown mostly by in vitro studies to utilize matrix metalloproteinase (MMP) for invasive growth through degradation of the extracellular matrix. In order to examine the in vivo role of MMP, we established a rodent model of glioma progression using C6 rat glioma cells and analyzed the effect of tissue inhibitors of metalloproteinases (TIMPs). TIMP-2 rather than TIMP-1 caused significant reduction of the tumor size accompanied by the presence of degenerated blood vessels and ischemic necrosis. Because TIMP-2 inhibits MMP-2 preferentially, we then examined glioma growth in MMP-2-deficient mice and observed essentially identical consequences. While MMP-2 activity was present in the tumor and adjacent tissues of the wild-type mice, no MMP-2 activity was detected even in the tumor of the null mice, although C6 cells are known to express MMP-2. These observations suggest that glioma induces MMP-2 and utilizes its activity in the host tissue to support angiogenesis and to maintain angioarchitecture. 相似文献