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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
64.
This study illustrates the local spread of lower bile duct cancer with thin-section helical CT in correlation with the surgical
and pathological findings. Pathologically, 16 patients had pancreatic invasion, 4 had small bowel mesentery invasion, 7 had
extrapancreatic nerve plexus invasion, and 3 patients had vascular invasion. On thin-section helical CT, pancreatic invasion
was correlated to the clarity or non-clarity of the bile duct mass-pancreas border and the presence of an intrapancreatic
mass. Cases with small bowel mesentery and extrapancreatic nerve plexus invasion showed mass or stranding around the superior
mesenteric artery and/or inferior pancreatoduodenal artery. Vascular invasion was seen as tumor contiguity to these vessels.
Received: 28 September 1998; Revised: 30 December 1998; Accepted: 2 April 1999 相似文献
65.
Nagata T Matsuyama M Kiriike N Iketani T Oshima J 《The Journal of nervous and mental disease》2000,188(5):280-286
Although maladaptive coping strategies in eating disorder patients have been reported, the relationship between impulsivity and coping strategy has not previously been studied. Subjects consisted of 43 patients with anorexia nervosa restricting type (AN-R), 42 patients with anorexia nervosa binge eating/purging type (AN-BP), 71 patients with bulimia nervosa purging type (BN), and 97 controls. The Coping Inventory for Stressful Situations was used to evaluate coping strategies. Only AN-BP patients had a significantly lower task oriented-coping score than controls, and AN-R and BN patient groups used significantly less social diversion-avoidance coping strategies than controls. Emotion-oriented coping scores of AN-BP and BN patients were significantly higher than those of controls. In addition, impulsive BN patients had significantly higher emotional coping scores than less impulsive BN patients. These results suggest that maladaptive coping strategies may be a perpetuating factor even for impulsive patients and emphasizing a change in maladaptive coping strategies may be a useful treatment strategy even for highly impulsive patients. 相似文献
66.
Up-regulation of glial cell line-derived neurotrophic factor (GDNF) following traumatic spinal cord injury 总被引:10,自引:0,他引:10
Satake K Matsuyama Y Kamiya M Kawakami H Iwata H Adachi K Kiuchi K 《Neuroreport》2000,11(17):3877-3881
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Sugita T Matsumoto M Ogino H Nishizawa J Matsuyama K Yoshimura S Yoshioka T Tokuda Y Matsumura M Suda K Ueda Y 《Kyobu geka. The Japanese journal of thoracic surgery》2000,53(10):853-856
Forty-eight patients who underwent right ventricular outflow tract reconstruction with Monocusp Ventricular Outflow Patch (MVOP) fifty-five times and survived surgery, were reviewed in this study. Mean age at surgery was 6.4 years-old and mean follow-up interval was 75.2 months. There was no late death, however reoperation was performed 7 times. Freedom from reoperation rate was 97.2% and 80.7% after 5 and 10 years after surgery, respectively. The main cause for reoperation were right ventricular outflow obstruction RVOTO (5 cases). All of the RVOTO occurred at the distal end of the anastomosis. However, there was no RVOTO in patients who underwent RVOTR with MVOP during the past ten years. So, we considered the cause of RVOTO a technical problem. Pulmonary regurgitation was one to two degree early after surgery, and had worsened by almost two or three degrees more than 5 years after surgery. Moreover, five of six patients who underwent cardiac catheterization more than 10 years after surgery had three degrees of pulmonary regurgitation as well as a large CTR. In conclusion, according to long-term results, especially more than 10 years post operatively, pulmonary regurgitation was the most important problem. 相似文献
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