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排序方式: 共有10000条查询结果,搜索用时 140 毫秒
991.
Yuichiro Tanaka Masahiro Sasaki Hiroaki Shiina Takashi Tokizane Masao Deguchi Hiroshi Hirata Yuji Hinoda Naoko Okayama Yutaka Suehiro Shinji Urakami Toshifumi Kawakami Masanori Kaneuchi Deepa Pookot Mikio Igawa Akihiko Okuyama Nobuhisa Ishii Rajvir Dahiya 《Cancer epidemiology, biomarkers & prevention》2006,15(2):238-244
Various carcinogenic metabolites, including catechol estrogens, play a role in malignant transformation. An enzyme that is capable of neutralizing the genotoxic effects of these compounds is catechol-O-methyltransferase (COMT). A variant form of this enzyme has been shown to reduce its activity by up to 4-fold; thus, we hypothesize that single nucleotide polymorphisms of the COMT gene can be a risk factor for benign prostatic hyperplasia (BPH) and prostate cancer. To test this hypothesis, the genetic distribution of three different COMT polymorphisms at codon 62 (C-->T), codon 72 (G-->T), and codon 158 (G-->A) were analyzed in 131 normal healthy subjects, 134 BPH, and 178 sporadic prostate cancer samples from a Japanese population. Results of these experiments show that the variant genotype at codon 62 (P = 0.060) and codon 158 (P = 0.047) are risk factors for prostate cancer but not BPH when compared with normal controls. Odds ratio (OR) and 95% confidence interval (95% CI) for cancer were 3.24 and 1.38 to 7.61, respectively, for codon 62 T/T genotype when compared with wild type. At codon 158, the A/A variant for cancer had an OR of 3.00 with a 95% CI of 1.38 to 6.54 compared with wild type. Codons 62 and 158 were in linkage disequilibrium (LD), and when compared with the C-G haplotype, other types (C-A, T-G, T-A) were observed to be associated with prostate cancer (P = 0.040) but not BPH. Codon 72 on the other hand, was not in LD with either codon 62 or 158. The homozygous variant on codon 72 was rare in this Japanese population, and the heterozygous G/T at this codon was not associated with either prostate cancer or BPH. When evaluating the risk of COMT polymorphisms with stage or grade of cancer, no associations were observed for any of the genotypes with the exception of a tendency (P = 0.096) for the variant A allele on codon 158 to be correlated with higher stages (> or = T3) of cancer. This is the first report that shows the polymorphisms of COMT to be associated with sporadic prostatic carcinogenesis. These results are important in understanding the role of COMT polymorphisms in the pathogenesis of prostate cancer. 相似文献
992.
Mizuno K Okada M Murakami T Kamata A Zhu G Kawata Y Wada K Kaneko S 《Epilepsy research》2000,40(2-3):187-195
To clarify the mechanisms of action of carbamazepine (CBZ), we investigated the effects of CBZ on acetylcholine (ACh) release and metabolism in rat striatum and hippocampus. Acute administration of effective dose of CBZ (25 mg/kg) increased both striatal and hippocampal extracellular levels of ACh, whereas a supraeffective dose of CBZ (50 mg/kg) did not affect the levels and a toxic dose of CBZ (100 mg/kg) decreased the extracellular ACh levels in both brain regions. Both acute and chronic administrations of CBZ (25 and 50 mg/kg, mg/kg per day) increased intracellular ACh levels in striatum and hippocampus. The striatal intracellular ACh levels were decreased by both acute and chronic administrations of CBZ (100 mg/kg, mg/kg per day), whereas the hippocampal intracellular ACh levels were not affected. The effective CBZ concentration did not affect cholinesterase activity, whereas supraeffective CBZ concentration reduced it weakly. Effective dose of CBZ enhanced ACh release and synthesis; however, supraeffective doses of CBZ reduced ACh release and synthesis without enhancement of ACh degradation, indicating that CBZ has biphasic effects on ACh release and synthesis. Thus, the present findings, the slight stimulation of ACh function by effective dose of CBZ, are involved, at least partially, in the antiepileptic and mood stabilizing mechanisms of action of CBZ. 相似文献
993.
Splenic Vein Occlusion Secondary to Tuberculous Lymphadenitis at the Splenic Hilum: Report of a Case
(Received for publication on Dec. 16, 1998; accepted on Nov. 11, 1999) 相似文献
994.
We report herein the case of an 81-year-old woman found to have small intestinal carcinoma producing carbohydrate antigen
(CA)19-9, in whom recurrence on the abdominal wall was strongly suspected 4 months after resection. She presented to our hospital
with acute abdominal pain with severe anemia. Marked serum elevation of CA19-9 to 164.8 U/ml suggested a progression to malignancy.
A fluorography using an ileus tube revealed an abnormal mucosal pattern. An exploratory laparotomy showed an incomplete annular
constrictive Borrmann type 2 tumor, located approximately 190 cm from Treitz's ligament, without any signs of peritoneal or
hepatic metastases. Histological examination confirmed a diagnosis of papillotubular adenocarcinoma without metastases of
the regional lymph nodes. CA19-9 antigenicity was detected in the cytoplasm and on the surface of the cancer cells, using
the monoclonal CA19-9 antibody, NS19-9. In this report, we demonstrate the CA19-9 productivity and distribution of the cancer
tissues in relation to their prognosis.
Received: August 17, 1999 / Accepted: March 24, 2000 相似文献
995.
Yuji Shimamoto Hiromi Kazuno Yuko Murakami Atsushi Azuma Katsuhisa Koizumi Akira Matsuda Takuma Sasaki Masakazu Fukushima 《Japanese journal of cancer research》2002,93(4):445-452
We have established variants of DLD-1 human colon carcinoma and HT-1080 human fibrosarcoma cells resistant to the new anticancer ribo-nucleosides, 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)-cytosine (ECyd, TAS-106) and 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)uracil (EUrd). Both variants were shown to have decreased (3- to 24-fold decrease) uridine-cytidine kinase (UCK) activity, and exhibited cross-resistance to EUrd and TAS-106. Based on the IC(50) values determined by chemosensitivity testing, a 41- to 1102-fold resistance to TAS-106 was observed in the resistant cells. TAS-106 concentration-dependently inhibited RNA synthesis, while its effect on DNA synthesis was negligible. The degree of resistance (14- to 3628-fold resistance) calculated from the inhibition of RNA synthesis tended to be close to the degree of chemoresistance of tested cells to TAS-106. The experiments on the intracellular metabolism of TAS-106 in the parental cells revealed a rapid phosphorylation to its nucleotides, particularly the triphosphate (ECTP), its major active metabolite. The amount of TAS-106 transported into the resistant cells was markedly reduced and the intracellular level of ECTP was decreased from 1/19 to below the limit of detection; however, the unmetabolized TAS-106 as a percentage of the total metabolite level was high as compared with the parental cells. The ratio of the intracellular level of ECTP between parental and resistant cells tended to approximate to the degree of resistance calculated from the inhibitory effect on RNA synthesis. These results indicate that the TAS-106 sensitivity of cells is correlated with the intracellular accumulation of ECTP, which may be affected by both the cellular membrane transport mechanism and UCK activity. 相似文献
996.
J Takeuchi T Kyo K Naito H Sao M Takahashi S Miyawaki K Kuriyama S Ohtake F Yagasaki H Murakami N Asou T Ino T Okamoto N Usui M Nishimura K Shinagawa T Fukushima H Taguchi T Morii S Mizuta H Akiyama Y Nakamura T Ohshima R Ohno 《Leukemia》2002,16(7):1259-1266
In order to improve the disappointing prognosis of adult patients with acute lymphoblastic leukemia (ALL), we applied similar induction therapy as that used for acute myeloid leukemia (AML), ie frequent administration of doxorubicin (DOX). DOX 30 mg/m(2) was administered from days 1 to 3 and from days 8 to 10 together with vincristine, prednisolone, cyclophosphamide and L-asparaginase, followed by three courses of consolidation and four courses of intensification. From December 1993 to February 1997, 285 untreated adult patients with de novo ALL were entered. Of 263 evaluable patients (age 15 to 59; median 31), 205 (78%) obtained complete remission (CR). At a median follow-up period of 63 months, the predicted 6-year overall survival (OS) rate of all patients was 33%, and disease-free survival (DFS) rate of CR patients was 30%, respectively. By multivariate analysis, favorable prognostic factors for the achievement of CR were age <40 and WBC <50 000/microl; for longer OS were age <30 and WBC <30 000/microl; and for longer DFS of CR patients were FAB L1 and ALT <50 IU/l. Among 229 patients who had adequate cytogenetic data, 51 (22%) had Philadelphia (Ph) chromosome. Ph-negative chromosome was a common favorable prognostic factor for CR, longer OS and DFS. DFS was not different between early sequential intensification (n = 48) and intermittent intensification (n = 43) during the maintenance phase. Among CR patients under 40 years old, the 6-year survival was not different between the allocated related allo-BMT group (34 patients) and the allocated chemotherapy group (108 patients). However, among patients with Ph-positive ALL, the survival of patients who actually received allo-BMT was superior to that of patients who received chemotherapy (P = 0.046). 相似文献
997.
Yuji Shimamoto Katsuhisa Koizumi Hiroyuki Okabe Hiromi Kazuno Yuko Murakami Fumio Nakagawa Akira Matsuda Takuma Sasaki Masakazu Fukushima 《Cancer science》2002,93(7):825-833
TAS–106 [l–(3– C -ethynyl-β- d - ribo -pentofuranosyl)cytosine] is a new anticancer ribo -nucleoside with promising antitumor activity. We have previously presented evidence suggesting that the TAS–106 sensitivity of cells is correlated with intracellular accumulation of the triphosphate of TAS–106, which may be affected both by cellular membrane transport mechanisms and uridine-cytidine kinase (UCK) activity. Since the presence of a UCK family consisting of two members, UCK1 and UCK2, has recently been reported in human cells, we investigated the relation between expression of UCK1 and UCK2 at both the mRNA and protein levels and UCK activity (TAS–106 phosphorylation activity) in a panel of 10 human cancer cell lines. Measurement of UCK activity in these cell lines revealed that it was well correlated with the cells' sensitivity to TAS–106. In addition, the mRNA or protein expression level of UCK2 was closely correlated with UCK activity in these cell lines, but neither the level of expression of UCK1 mRNA nor that of protein was correlated with enzyme activity. We therefore compared the protein expression level of UCK2 in several human tumor tissues and the corresponding normal tissues. Expression of UCK2 protein was barely detectable in 4 of the 5 human tumor tissues, but tended to be high in the pancreatic tumor tissue. It could not be detected at all in any of the normal tissues. Thus, expression of UCK2 appeared to be correlated with cellular sensitivity to TAS–106, and it may contribute to the tumor-selective cytotoxicity of TAS–106. 相似文献
998.
OBJECTIVE: To investigate the expression of matrix metalloproteinase-2 (MMP-2, reportedly associated with cancer cell invasion and metastasis in many human cancers) in urothelial tumours and thus define its role in this disease. Materials and methods The expression of both the activated form of MMP-2 and total MMP-2 (activated + latent form) was measured using gelatine zymography in tissue obtained surgically from 61 patients with urothelial cancer. The correlation between the level of the activated form of MMP-2 and clinical and histological variables was assessed. RESULTS: The expression of activated and total MMP-2 were significantly higher in invasive tumour tissue and both levels were correlated with histological grade. In particular, the level of activated MMP-2 was more closely correlated than that of total MMP-2 in invasive tumour tissue. Moreover, high levels of activated MMP-2 were strongly associated with shorter disease-specific survival (P = 0.0016). CONCLUSION: These findings suggest that activated MMP-2 plays a significant role in invasion of urothelial cancer and that the level of activated MMP-2 expression is a useful prognostic indicator. 相似文献
999.
1000.
Sakashita Y Hiyama E Imamura Y Murakami Y Sugahara Y Takesue Y Matsuura Y Yokoyama T 《Hiroshima journal of medical sciences》2000,49(1):43-48
In major systemic inflammation such as severe peritonitis, various pro-inflammatory cytokines, such as TNF-alpha, IL-1 beta and IL-6, play important roles in the development of multiple organ dysfunction syndrome (MODS). The purpose of this study was to investigate the outflow of pro-inflammatory and anti-inflammatory cytokines from the efferent mesenteric lymphatic vessels under peritonitis. Mesenteric lymph samples were collected from adult male rats at 2, 4, 6, 8 and 10 hr after an intraperitoneal injection of zymosan at a dosage of 0.1 mg/g (non-lethal dose) or 0.5 mg/g (lethal dose). Blood samples were obtained at 10 hr after zymosan administration. The amounts of drained TNF-alpha and IL-6 in the lymph peaked at 2-4 hr and 4-8 hr after zymosan administration, respectively. The amounts of drained IL-10 in the lymph gradually increased until 10 hr. The amounts of drained TNF-alpha and IL-10 in the mesenteric lymph were significantly correlated with the dosage of zymosan. In conclusion, under intraperitoneal inflammation, pro-inflammatory cytokines (TNF-alpha and IL-6) increased in the mesenteric lymph and were drained into circulation. IL-10, one of the anti-inflammatory cytokines, also increased in the mesenteric lymph after several hours' delay and its increase was remarkable in several inflammations. These findings suggested that the gut might be one of the pro-inflammatory and anti-inflammatory cytokine-generating organs under peritonitis. The lymph-drained amounts of each cytokine under peritonitis are considered to differ with the time or severity of inflammation, which may cause different conditions in patients due to the imbalance of pro-inflammatory and anti-inflammatory cytokines. 相似文献