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71.
Shin-ichiro Masunaga M.D. Ph.D. Koji Ono M.D. Ph.D. Yoshinori Sakurai D.Eng. Masao Takagaki M.D. Ph.D. Toru Kobayashi D.Eng. Minoru Suzuki M.D. Yuko Kinashi M.D. Ph.D. Mitsuhiko Akaboshi Ph.D. 《International journal of radiation oncology, biology, physics》1998,41(5):365
Purpose: Response of quiescent (Q) and total tumor cells in solid tumors to neutron irradiation with three different cadmium (Cd) ratios was examined. The role of Q cells in tumor control was also discussed.Methods and Materials: C3H/He mice bearing SCC VII tumors received continuous administration of 5-bromo-2′-deoxyuridine (BrdU) for 5 days using implanted mini-osmotic pumps to label all proliferating (P) cells. Thirty minutes after intraperitoneal injection of sodium borocaptate-10B (BSH), or 3 h after oral administration of dl-p-boronophenylalanine-10B (BPA), the tumors were irradiated with neutrons, or those without 10B-compounds were irradiated with gamma rays. This neutron irradiation was performed using neutrons with three different cadmium (Cd) ratios. The tumors were then excised, minced, and trypsinized. The tumor cell suspensions were incubated with cytochalasin-B (a cytokinesis-blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (Q cells) was determined using immunofluorescence staining for BrdU. The MN frequency in total (P + Q) tumor cells was determined from tumors that were not pretreated with BrdU. The sensitivity to neutrons was evaluated in terms of the frequency of induced micronuclei in binuclear tumor cells (MN frequency).Results: Without 10B-compounds, the MN frequency in Q cells was lower than that in the total cell population. The sensitivity difference between total and Q cells was reduced by neutron irradiation. Relative biological effectiveness (RBE) of neutrons compared with gamma rays was larger in Q cells than in total cells, and the RBE values for low-Cd-ratio neutrons tended to be larger than those for high-Cd-ratio neutrons. With 10B-compounds, MN frequency for each cell population was increased, especially for total cells. This increase in MN frequency was marked when high-Cd-ratio neutrons were used. BPA increased the MN frequency for total tumor cells more than BSH. Nevertheless, the sensitivity of Q cells treated with BPA was lower than that in BSH-treated Q cells. This tendency was clearly observed in high-Cd-ratio neutrons.Conclusion: From the viewpoint of enhancing the Q-cell sensitivity, tumors should be irradiated with high-Cd-ratio neutrons after BSH administration. However, normal tissue reaction remains to be examined because of its low tumor-to-normal tissue and tumor-to-blood biodistribution ratios. 相似文献
72.
Expression of apoptosis-related proteins in adenomyotic uteri treated with danazol and GnRH agonists. 总被引:2,自引:0,他引:2
Ken Ueki Koji Kumagai Hidetoshi Yamashita Zhong-lian Li Minoru Ueki Yoshinori Otsuki 《International journal of gynecological pathology》2004,23(3):248-258
The biologic properties of adenomyosis and the effects of therapeutic agents on adenomyosis were evaluated with immunohistochemistry, terminal deoxy-nucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method, transmission electron microscopy, and analysis of genomic abnormality. In the adenomyotic endometrium, estrogen receptor (ER) expression was more intense than in the eutopic endometrium during the secretory phase, and bcl-2 was constantly expressed throughout the menstrual cycle. The expression of ER and bcl-2 was weaker in the adenomyotic endometrium treated with danazol than in that treated with gonadotro-pin-releasing hormone agonist (GnRHa), whereas bcl-2 phosphorylated on serine-87 was more intensely expressed in danazol-treated adenomyotic endometrium than in the GnRHa-treated one. The number of TUNEL-positive cells increased in the adenomyotic endometrium treated with danazol or GnRHa. Ultrastructurally, most of the adenomyotic endometrial cells treated with danazol underwent postapoptotic necrosis and formed a cluster of dead cells. In contrast, cells treated with GnRHa underwent typical apoptosis and were sparsely distributed in the adenomyotic endometrium. Analysis of several cancer-related genes showed no microsatellite instability or loss of heterozygosity in adenomyotic tissues. Therefore, we conclude that the occurrence of adenomyosis is correlated to bcl-2 expression regulated by estrogen and ER rather than genetic mutation. 相似文献
73.
Akemi Irie Akira Yamauchi Keiichi Kontani Minoru Kihara Dage Liu Yukako Shirato Masako Seki Nozomu Nishi Takanori Nakamura Hiroyasu Yokomise Mitsuomi Hirashima 《Clinical cancer research》2005,11(8):2962-2968
PURPOSE: Galectin-9, a member of the beta-galactoside-binding galectin family, induces aggregation of certain cell types. We assessed the contribution of galectin-9 to the aggregation of breast cancer cells as well as the relation between galectin-9 expression in tumor tissue and distant metastasis in patients with breast cancer. EXPERIMENTAL DESIGN: Subclones of MCF-7 breast cancer cells with high or low levels of galectin-9 expression were established and either cultured on plastic dishes or transplanted into nude mice. The tumors of 84 patients with breast cancer were tested for galectin-9 expression by immunohistochemistry. The patients were followed up for 14 years. RESULTS: MCF-7 subclones with a high level of galectin-9 expression formed tight clusters during proliferation in vitro, whereas a subclone (K10) with the lowest level of galectin-9 expression did not. However, K10 cells stably transfected with a galectin-9 expression vector aggregated in culture and in nude mice. Ectopic expression of galectin-9 also reduced MCF-7 cell adhesion to extracellular matrix proteins. Tumors of 42 of the 84 patients were galectin-9 positive, and those of 19 of the 21 patients with distant metastasis were galectin-9 negative. None of the 13 patients with galectin-9-positive tumors and lymph node metastasis up to level II manifested distant metastasis. The cumulative disease-free survival ratio for galectin-9-positive patients was more favorable than that for the galectin-9-negative group (P < 0.0001). Multivariate analysis revealed that galectin-9 status influenced distant metastasis independently of and to a greater extent than lymph node metastasis. CONCLUSIONS: Galectin-9 is a possible prognostic factor with antimetastatic potential in breast cancer. 相似文献
74.
Masaham Kinoshita Yasuhiro Nakamura Ryuji Nakano Minoru Morimatsu Seiichi Fukuda Yasuhiro Nishimi Takeo Hashimoto 《Fetal and pediatric pathology》1989,9(4):445-457
The clinical features and morphological findings in 31 Japanese infants with trisomy 18 are presented. The majority were small-for-date infants. There was no sex predominance in our series, as opposed to male female ratios of 1:3 reported in the literature. The average age at death was greater in females than in males. Cardiovascular anomalies were consistently present; ventricular septar defect and patent ductus arteriosus being the most common malformations. Various other internal malformations including the Arnold-Chiari malformation were observed. 相似文献
75.
76.
Atsushi Sato Ken Shimada Masatoshi Nakamachi Jun Ushio Wataru Yamamoto Minoru Kurihara Masaaki Matsukawa 《Gastric cancer》2002,5(4):0233-0236
A 58-year-old man was diagnosed as having type 3 gastric cancer (poorly differentiated adenocarcinoma). He underwent total
gastrectomy with splenectomy, as well as D3 dissection, and received postoperative chemotherapy combining oral uracil and
futrafur (UFT) with cisplatin (CDDP), but results showed recurrence of multiple abdominal lymph node metastases around the
aorta. He therefore received various anticancer drug regimens (irinotecan [CPT-11]/CDDP; 1 M tegafur-0.4 M gimeracil-1 M oteracil
potassium [TS-1], methotrexate (MTX)/5-fluorouracil); however, final results showed growth of lymph node metastasis and simultaneous
worsening of his general condition. The patient then received combined administration of doxifluridine (5′-DFUR)/docetaxel
(5′-DFUR, 1000 mg/body [666.7 mg/m
2
], given by consecutive daily administration, orally, for days 1–14; and docetaxel, 80 mg/body [60 mg/m
2
], on day 8, by venous drip, every 3 weeks). Three courses of this regimen resulted in approximately 90% reduction of the
abdominal lymph node size, disappearance of the right cervical lymph node metastasis, reductions of the levels of two tumor
markers (carcinoembryonic antigen [CEA] and carbohydrate antigen [CA]19-9), and improvement of his general condition. In total,
seven courses of the regimen were carried out. The patient died on day 298 after starting this combined regimen and showed
a response period of 126 days. The primary toxicity identified was neutropenia (grade 4), as well as other low-grade (grade
1, 2) hematological and nonhematological toxicities. In the field of gastric cancer treatment, especially for patients showing
multiple resistance to anticancer drugs, an effective therapy is critically needed.
Received: January 15, 2002 / Accepted: July 8, 2002
Offprint requests to: A. Sato 相似文献
77.
Shibuya H Hamamura K Hotta H Matsumoto Y Nishida Y Hattori H Furukawa K Ueda M Furukawa K 《Cancer science》2012,103(9):1656-1664
The expression and implications of gangliosides in human osteosarcomas have not been systematically analyzed. In this study, we showed that gangliosides GD3 and GD2 are highly expressed in the majority of human osteosarcoma cell lines derived from oral cavity regions. Introduction of GD3 synthase cDNA into a GD3/GD2-negative (GD3/GD2-) human osteosarcoma subline resulted in the establishment of GD3/GD2+ transfectant cells. They showed increased cell migration and invasion activities in wound healing and Boyden chamber invasion assays, respectively, compared to the control cells. When treated with serum, GD3/GD2+ cells showed stronger tyrosine phosphorylation of p130Cas, focal adhesion kinase, and paxillin than GD3/GD2- cells. In particular, paxillin underwent much stronger phosphorylation, suggesting its role in cell motility. Furthermore, we tried to dissect the roles of GD3 and GD2 in the malignant properties of the transfectant cells by establishing single ganglioside-expressing cells, that is, either GD3 or GD2. Although GD3/GD2+ cells showed the most malignant properties, GD2+ cells showed almost equivalent levels to GD3/GD2+ cells in invasion and migration activities, and in the intensities of tyrosine phosphorylation of paxillin. Among Src family kinases, Lyn was expressed predominantly, and was involved in the invasion and motility of GD3- and/or GD2-expressing transfectants. Furthermore, it was elucidated by gene silencing that Lyn was located in a different pathway from that of FAK to eventually lead paxillin activation. These results suggested that GD2/GD3 are responsible for the enhancement of the malignant features of osteosarcomas, and might be candidate targets in molecular-targeted therapy. 相似文献
78.
79.
Repetitive transcranial magnetic stimulation for protection against delayed neuronal death induced by transient ischemia 总被引:18,自引:0,他引:18
OBJECT: Data in the present study demonstrate that repetitive transcranial magnetic stimulation (rTMS) induces ischemic tolerance against delayed neuronal death (DND) of hippocampal neurons following an otherwise lethal ischemic insult. METHODS: Various regimens of rTMS were delivered to adult gerbils at various times prior to an episode of ischemia induced by transient (5-minute) bilateral common carotid artery (CCA) occlusion. The extent of DND in the CA1 region of the hippocampus was assessed quantitatively 7 days after the transient ischemic episode. When rTMS was delivered 2 to 5 days prior to bilateral CCA occlusion, DND was substantially attenuated; delivery of rTMS 12 to 24 hours prior to occlusion induced partial tolerance. In the group of animals that had received stimulation 2 days prior to occlusion, neuron density in the CA1 sector was significantly higher (three gerbils, 210.33, 86.01% of normal) than in the group that experienced ischemia only (three gerbils, 10.66, 4.36% of normal). A similar degree of neuron sparing occurred when stimulation was delivered 3, 4, or 5 days prior to occlusion. Note that rTMS was effective when it was delivered at frequencies of 25 and 50 Hz. Stimulation at 25 Hz for 128 seconds (3200 pulses) was more effective than stimulation at 50 Hz for 64 seconds (3200 pulses) or 128 seconds (6400 pulses), however. CONCLUSIONS: Noninvasive rTMS represents an important tool for exploring the mechanisms of ischemic tolerance and preventing ischemic neuronal damage. 相似文献
80.
目的: 探讨转录调控因子CBF1(C-promoter binding factor-1, CBF1)在成鼠骨组织以及小鼠胚胎性骨组织的表达情况.方法: 采用实时RT-PCR方法检测包括骨组织在内的成年小鼠13种器官组织中CBF1的相对表达水平.采用组织原位杂交技术检测小鼠胚胎性趾骨、肋骨和椎骨中CBF1的分布.结果: 转录调控因子CBF1在成年小鼠各组织器官中广泛存在,在骨组织中检测到较高的CBF1表达水平.原位杂交分析显示: 发育中的趾骨和肋骨软骨细胞CBF1阳性染色,染色阳性程度与软骨细胞的分化程度有关;肋骨和椎骨骨化区周围成骨细胞呈强阳性染色;埋入骨基质的骨细胞则呈弱阳性染色.结论: 转录调控因子CBF1参与了小鼠骨组织的发育形成,可能也参与了成熟骨组织的改建和代谢. 相似文献