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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3.
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Summary Cranial computed tomography (CT) of 108 cases with dilated lateral ventricles was reviewed to elucidate the relationship between focal vulnerability of developing brain and disproportional dilatation of lateral ventricles. CT findings of 108 cases with symmetrical dilatation of lateral ventricles were classified into three types by morphometry of lateral ventricles: anterior horn predominant type (31 cases), diffuse type (36 cases), posterior horn predominant type (41 cases). Posterior horn predominant type has a tendency to occur in congenital anomalies and premature brain damage, and anterior horn predominant type in infantile brain damage. This disproportional dilatation of anterior or posterior horns suggests a vulnerability of periventricular structure in developing brain. 相似文献
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Keisuke Mitsuoka Sosuke Miyoshi Yukio Kato Yoshihiro Murakami Rie Utsumi Yoshiyuki Kubo Akihiro Noda Yukio Nakamura Shintaro Nishimura Akira Tsuji 《Journal of nuclear medicine》2008,49(4):615-622
H+/peptide transporter, PEPT1, is functionally expressed in some human cancer cell lines and might be a candidate molecular target for detection of cancers in vivo using PET. The aim of the present study was to establish a novel tumor-imaging technology using a PET tracer targeted to H+/peptide transporter(s). We also compared the tracer with 18F-FDG, focusing on the specificity of their accumulation between tumor and inflammatory tissues. METHODS: A dipeptide PET tracer, 11C-glycylsarcosine (11C-Gly-Sar), was injected intravenously into athymic mice transplanted with human pancreatic, prostate, and gastric cancer cells. The distribution patterns of 11C-Gly-Sar and 18F-FDG in the tumor-bearing mice, and in mice with inflammatory tissue, were assessed by imaging with a positron planar imaging system (PPIS). Tissue distributions of tracer radioactivity were also measured. The expression levels of PEPT1 and PEPT2 (PEPTs) proteins in tumor xenografts and inflammatory tissue were examined by immunohistochemical analysis. The messenger RNA expression levels of PEPTs in 58 available cancer cell lines were quantified by means of real-time polymerase chain reaction. RESULTS: All 3 tumor xenografts were well visualized with the PPIS after injection of 11C-Gly-Sar. Expression of PEPTs in those xenografts was confirmed by immunohistochemical analysis. Tumor-to-blood concentration ratios of 11C-Gly-Sar increased in a time-dependent manner and were much higher than unity. Most of the radioactivity found in the tumor tissue was recovered as the intact tracer. These results indicated that 11C-Gly-Sar was taken up by the PEPTs in tumor xenografts. It is noteworthy that 11C-Gly-Sar was minimally present in inflammatory tissues that expressed no PEPT1 or PEPT2 protein, whereas 18F-FDG was highly accumulated, with the values of the selectivity index being >25.1 and 0.72 for 11C-Gly-Sar and 18F-FDG, respectively. The mRNAs of PEPT1 and PEPT2 were expressed in 27.6% and 93.1%, respectively, of the cancer cell lines examined in the present study. CONCLUSION: The present study indicates that 11C-Gly-Sar is a promising tumor-imaging agent and is superior to 18F-FDG for distinguishing between tumors and inflammatory tissue. Because PEPTs were ubiquitously expressed in various types of tumor cells examined, 11C-Gly-Sar could be useful for the detection of many types of cancers. 相似文献
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Makoto Osawa Yutaka Ito Toyohiro Hirai Rie Isozumi Shunji Takakura Yasuhiro Fujimoto Yoshitsugu Iinuma Satoshi Ichiyama Koichi Tanaka Michiaki Mishima 《Liver transplantation》2007,13(4):566-570
Invasive aspergillosis (IA) is a severe complication of liver transplantation. Risk factors for IA after deceased donor liver transplantation (DDLT) have been presented in several reports, but are not well established for living donor liver transplant recipients. Here, a retrospective case-control study was performed. Five cases with IA were investigated after living donor liver transplantation (LDLT) between January 1999 and December 2002 at Kyoto University Hospital. For comparison, living donor liver transplant recipients without IA were taken as controls. These patients had undergone LDLT 1 month before or after each IA case and had the same survival times as the latter. We evaluated the clinical and laboratory findings for both groups up until their demise. Patients with IA after LDLT had a very poor prognosis. By univariate analysis, risk factors for IA were preoperative intensive care unit stay (P = 0.02) and preoperative steroid administration (P = 0.02). Preoperative steroid administration for fulminant hepatitis possibly predisposed to the development of IA after LDLT. 相似文献
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Noriko Yoshimura Tomoko Takijiri Hirofumi Kinoshita Shigeto Danjoh Takahiro Kasamatsu Seiji Morioka Kiyomi Sakata Tsutomu Hashimoto Tatsuya Takeshita 《Osteoporosis international》2004,15(2):139-144
The aim of this study was to clarify and compare the temporal course of bone mineral density (BMD) between fast bone losers and normal residents in Miyama Village, a rural Japanese community. BMD was measured over a 10-year period in a cohort study in Miyama Village, Wakayama Prefecture, Japan, to provide information on rate of bone loss in the mature and elderly population. Subjects (n=400) were selected by sex and age stratum from the full list of residents born in 1910–1949, with 50 men and 50 women in each age decade. Baseline BMD of the lumbar spine and proximal femur was measured using dual energy X-ray absorptiometry in 1990, 1993, 1997 and 2000. In the cohort, 171 men and 189 women completed the follow-up survey performed in 1993. After calculating the rate of bone loss between 1990 and 1993, the greatest tertile from the distribution of bone loss was categorized as fast bone losers, with the remainder considered as normal subjects. Changes in BMD were compared between normal subjects and fast bone losers over the 10-year period. Mean rate of change for BMD at both lumbar spine and femoral neck in fast bone losers recovered to levels similar to those in normal subjects over 7 years of observation. By contrast, BMD at the lumbar spine and femoral neck decreased steeply over the 10-year period in both groups, and mean BMD for fast bone losers was significantly lower than that of normal subjects (P<0.05). These differences were apparent only at the lumbar spine in both men and women, even after adjusting for age. These results indicate that fast bone loss is a transient phenomenon rather than a fixed status, although individuals who have been categorized as fast bone losers at some stage continue to display low BMD in the lumbar spine. 相似文献