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Shingo Hashimoto Masaki Katsurada Rie Muramatsu Kumiko Asai Kenichiro Tanaka Kensuke Hayashi Yoshiaki Kibe Koichiro Nakajima Yukiko Hattori Hiromitsu Iwata Jun-etsu Mizoe Hiroyuki Ogino Yuta Shibamoto 《Practical radiation oncology》2019,9(2):e149-e155
Purpose
Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.Methods and Materials
First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.Results
The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.Conclusions
The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target. 相似文献2.
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The effect of sodium 6-(2-(1-(1H)-imidazolyl)methyl-4,5-dihydrobenzo(b) thiophene)carboxylate (RS-5186), a potent and long acting thromboxane synthetase inhibitor in vitro and in vivo, on infarct size and on the infiltration of polymorphonuclear leukocytes (PMNs), was studied in a rabbit coronary artery occlusion (1 h)--reperfusion (0.5 h or 3 h) model. The infarcted region was stained with triphenyltetrazolium, and the ratio of infarcted area/left ventricular area was calculated. The infiltration of PMNs into the infarcted region was determined by measuring the PMNs specific enzyme, myeloperoxidase (MPO) activity. In the vehicle treated group, infarct size and MPO activity were increased with increased reperfusion time from 0.5 h to 3 h (infarct size: 15.3 +/- 2.7 to 25.2 +/- 3.2%; MPO activity: 255 +/- 51 to 825.3 +/- 169.4 units/g wet weight). There was also a significant correlation (r = 0.90, p less than 0.01) between the infarct size and MPO activity. In contrast, in the RS-5186 treated group (2 mg/kg i.v.), both infarct size and MPO activity did not increase with prolongation of the reperfusion period (infarct size: 12.8 +/- 5.5 to 10.3 +/- 3.6%; MPO activity: 318.8 +/- 36.7 to 381.2 +/- 72.6 units/g wet weight). In 0.5 h reperfused samples, there was no significant difference in infarct size or in MPO activity between the vehicle treated group and RS-5186 treated group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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S Kanba E Suzuki S Nomura T Nakaki G Yagi M Asai E Richelson 《Journal of psychiatry & neuroscience : JPN》1994,19(4):265-269
We determined the inhibition-dissociation constant (Ki) of a number of neuroleptics for D1 receptors of normal human brain tissue using [3H]SCH23390 [R-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3[benzazepine-7- ol]. SCH23390 had the highest affinity with a Ki of 0.76 nM. Among clinically used drugs, propericiazine showed the highest affinity with a Ki of 10 nM. When neuroleptics were classified according to chemical structures, the Ki values were as follows. Phenothiazines ranged from 10 nM to 250 nM. Butyrophenones ranged from 45 nM to 250 nM. Thioxanthenes ranged from 12 nM to 340 nM. Orthopramines were more than 10,000 nM. The Ki values for the binding site of this study were significantly correlated with those reported in studies using animal brain. The possible relationship between D1 receptors and negative symptoms is discussed. 相似文献
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Proteins from 21 cerebrospinal fluid (CSF) samples (14 derived from neurological cases and 7 from normal individuals) and 15 serum samples (11 from neurological cases and 4 from normal individuals) were analyzed by two-dimensional electrophoresis. Protein mapping revealed a very acidic protein (Ac-P) at about pH 3.5 in the 71% of CSF samples from neurological cases. However, no serum sample contained Ac-P. Ac-P was isolated and purified, and determined to be a glycoprotein containing a large amount of carbohydrate, with molecular weight 42,000 and isoelectric point 2.7-3.3. The amino acid composition of Ac-P was consistent with alpha 1-acid glycoprotein (AGP), and Ac-P was responsive to a commercial anti-AGP antiserum in the radial immunodiffusion test. The known polymorphism of AGP suggests some differences in physicochemical properties such as molecular weight and isoelectric point between AGP in serum and in CSF. Quantitative analysis of Ac-P (AGP) and total protein levels in CSF showed a partial interdependence. Ac-P may be a useful marker for detecting a pathological conditions of the central nervous system. 相似文献
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