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61.
The outcomes of three methods of intensity-modulated radiation therapy (IMRT) for localized prostate cancer were evaluated. Between 2010 and 2018, 308 D’Amico intermediate- or high-risk patients were treated with 2.2 Gy daily fractions to a total dose of 74.8 Gy in combination with hormonal therapy. Overall, 165 patients were treated with 5-field IMRT using a sliding window technique, 66 were then treated with helical tomotherapy and 77 were treated with volumetric modulated arc therapy (VMAT). The median age of patients was 71 years. The median follow-up period was 75 months. Five-year overall survival (OS) and biochemical or clinical failure-free survival (FFS) rates were 95.5 and 91.6% in the 5-field IMRT group, 95.1 and 90.3% in the tomotherapy group and 93.0 and 88.6% in the VMAT group, respectively, with no significant differences among the three groups. The 5-year cumulative incidence of late grade ≥2 genitourinary and gastrointestinal toxicities were 7.3 and 6.2%, respectively, for all patients. Late grade ≥2 gastrointestinal toxicities were less frequent in patients undergoing VMAT (0%) than in patients undergoing 5-field IMRT (7.3%) and those undergoing tomotherapy (11%) (P = 0.025), and this finding appeared to be correlated with the better rectal DVH parameters in patients undergoing VMAT. Other toxicities did not differ significantly among the three groups, although bladder dose-volume parameters were slightly worse in the tomotherapy group than in the other groups. Despite differences in the IMRT delivery methods, X-ray energies and daily registration methods, all modalities may be used as IMRT for localized prostate cancer.  相似文献   
62.
The irradiation field of boron neutron capture therapy (BNCT) consists of multiple dose components including thermal, epithermal and fast neutron, and gamma. The objective of this work was to establish a methodology of dosimetric quality assurance (QA), using the most standard and reliable measurement methods, and to determine tolerance level for each QA measurement for a commercially available accelerator-based BNCT system. In order to establish a system of dosimetric QA suitable for BNCT, the following steps were taken. First, standard measurement points based on tissue-administered doses in BNCT for brain tumors were defined, and clinical tolerances of dosimetric QA measurements were derived from the contribution to total tissue relative biological effectiveness factor-weighted dose for each dose component. Next, a QA program was proposed based on TG-142 and TG-198, and confirmed that it could be assessed whether constancy of each dose component was assured within the limits of tolerances or not by measurements of the proposed QA program. Finally, the validity of the BNCT QA program as an evaluation system was confirmed in a demonstration experiment for long-term measurement over 1 year. These results offer an easy, reliable QA method that is clinically applicable with dosimetric validity for the mixed irradiation field of accelerator-based BNCT.  相似文献   
63.
The dosimetric effect of set-up error in boron neutron capture therapy (BNCT) for head and neck cancer remains unclear. In this study, we analyzed the tendency of dose error by treatment location when simulating the set-up error of patients. We also determined the tolerance level of the set-up error in BNCT for head and neck cancer. As a method, the distal direction was shifted with an interval of 2.5 mm, from 0.0 mm to +20.0 mm and compared with the dose at the reference position. Similarly, the horizontal direction and vertical direction were shifted, with an interval of 5.0 mm, from −20.0 mm to +20.0 mm. In addition, cases with 3.0 mm and 5.0 mm simultaneous shifts in all directions were analyzed as the worst-case scenario. The dose metrics of the minimum dose of the tumor and the maximum dose of the mucosa were evaluated. From unidirectional set-up error analysis, in most cases, the set-up errors with dose errors within ±5% were Δdistal < +2.5 mm, Δhorizontal < ±5.0 mm and Δvertical < ±5.0 mm. In the simulation of 3.0 mm shifts in all directions, the errors in the minimum tumor dose and maximum mucosal dose were −3.6% ±1.4% (range, −5.4% to −0.6%) and 2% ±1.4% (range, 0.4% to 4.5%), respectively. From these results, if the set-up error was within ±3.0 mm in each direction, the dose errors of the tumor and mucosa could be suppressed within approximately ±5%, which is suggested as a tolerance level.  相似文献   
64.
The purpose of this study was to test the hypothesis that plasma levels of adiponectin can predict angiographic in-stent restenosis after coronary stenting. We prospectively examined adiponectin levels in 127 consecutive patients undergoing elective coronary stenting. Restenosis was defined as more than 50% stenosis at follow-up study by quantitative coronary angiography. There were no significant differences in the clinical characteristics or angiographical findings between the groups with restenosis and no restenosis. The levels of adiponectin did not differ between the restenosis group and the no restenosis group (5.7 +/- 2.8 vs 5.9 +/- 3.6 microg/mL, p = 0.72). The plasma levels of adiponectin were not related with the late loss index after coronary stenting (r = 0.01, p = 0.89). The levels of adiponectin were significantly lower in men than in women (5.5 +/- 3.2 vs 8.8 +/- 3.7 microg/ mL, p < 0.001), and negatively correlated with body mass index (r = -0.21, p = 0.01). We analyzed adiponectin levels in male, female, obese, non-obese, diabetes, and non-diabetes patients, however, there were no significant differences between the restenosis group and no restenosis group. This study has demonstrated that the measurement of adiponectin could not predict angiographic restenosis after elective coronary stenting, whereas the plasma levels of adiponectin were associated with some coronary risk factors in patients with coronary artery disease.  相似文献   
65.
A 19-year-old female belonging to a family of Alport's syndrome was autopsied and her kidneys were examined in detail light and electron microscopically. The basement membrane was examined chiefly and the laminated thickening and/or splitting, looseness, irregularity and rail-like appearance of lamina densa were found in the glomerular, Bowman's capsular, tubular and interstitial capillary basement membranes. These findings were strongly suggestive of Alport's syndrome, whether or not the particles are seen in the basement membrane. In addition, Japanese reports on Alport's syndrome (total 48 families) were summarized and renal lesions were examined in comparison. It has been said that the prognosis is worse in the male than in the female, but according to our Investigation on case reports in Japan, the prognosis showed no difference between male and female.  相似文献   
66.
We studied the MEN1 gene in a kindred where three patients (the proposita and two of her sons) were affected with hyperparathyroidism. By polymerase chain reaction (PCR)–based direct sequencing of 10 exons of MEN1, a novel germline mutation was identified in the proposita. This mutation, a T-to-A transition at codon 184 in exon 3, predicts an amino acid change from valine to glutamine (V184E). PCR–single-strand conformational polymorphism (PCR-SSCP) analysis of exon 3 followed by sequencing showed the same mutation in the two sons, and in two clinically normal granddaughters of an affected son. Since the T-to-A substitution segregated with the disorder in the kindred except for the granddaughters and it was not detected in 100 alleles from 50 normal individuals, the change observed in MEN1 is not a polymorphism, but causes familial hyperparathyroidism. Thus the two grandchildren with the mutation were diagnosed as presymptomatic carriers. Am. J. Med. Genet. 80:221–222, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
67.
Purple corn color is a widely used food colorant that was reported to have attenuating effects on hypertension, diabetes, and to have anti‐cancer effects on colon and breast cancer. Our study is the first on its possible chemoprevention effects against prostate cancer. For this purpose an androgen‐dependent prostate cancer cell line, LNCaP, was used to examine effects in vitro. Purple corn color inhibited the proliferation of LNCaP cells by decreasing the expression of Cyclin D1 and inhibiting the G1 stage of the cell cycle. Thirty‐six male transgenic rats for adenocarcinoma of prostate were fed basic diet or diet with purple corn color for 8 weeks. Purple corn color decreased the incidence of adenocarcinoma in the lateral prostate and slowed down the progression of prostate cancer. A lower Ki67 positive rate, a decrease of the expression of Cyclin D1, and downregulation of the activation of Erk1/2 and p38 MAPK were observed in the group consuming purple corn color in the diet. Since purple corn color is a mixture, determining its active component should help in the understanding and usage of purple corn color for prostate cancer chemoprevention. Therefore, the three major anthocyanins in purple corn color, cyanidin‐3‐glucoside, pelargonidin‐3‐glucoside and peonidin‐3‐glucoside, were tested with LNCaP cells. The results suggested that cyanidin‐3‐glucoside and pelargonidin‐3‐glucoside are the active compounds.  相似文献   
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IntroductionNonalcoholic fatty liver disease (NAFLD) is diagnosed after excluding other liver diseases. The pathogenesis of NAFLD when complicated by other liver diseases has not been established completely. Metabolic dysfunction‐associated fatty liver disease (MAFLD) involves more metabolic factors than NAFLD, regardless of complications with other diseases. This study aimed to clarify the effects of fatty liver occurring with metabolic disorders, such as MAFLD without diabetes mellitus (DM), on the development of DM.Materials and MethodsWe retrospectively assessed 9,459 participants who underwent two or more annual health check‐ups. The participants were divided into the MAFLD group (fatty liver disease with overweight/obesity or non‐overweight/obesity complicated by metabolic disorders), simple fatty liver group (fatty liver disease other than MAFLD group), metabolic disorder group (metabolic disorder without fatty liver disease), and normal group (all other participants).ResultsThe DM onset rates in the normal, simple fatty liver, metabolic disorder, and MAFLD groups were 0.51, 1.85, 2.52, and 7.36%, respectively. In the multivariate analysis, the MAFLD group showed a significantly higher risk of DM onset compared with other three groups (P < 0.01). Additionally, the risk of DM onset was significantly increased in fatty liver disease with overweight/obesity or pre‐diabetes (P < 0.01).ConclusionsFatty liver with metabolic disorders, such as MAFLD, can be used to identify patients with fatty liver disease who are at high risk of developing DM. Additionally, patients with fatty liver disease complicated with overweight/obesity or prediabetes are at an increased risk of DM onset and should receive more attention.  相似文献   
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