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The purpose of this study is to evaluate the mechanical accuracy of a respiratory-gated radiation system that combines the Linear Indicator-equipped Abches respiration-monitoring device and the Varian Real-time Position Management system (LI-RPM system). This combined configuration, implemented for the first time in Japan, was compared with the stand-alone Varian RPM system (RPM system). The delay times, dose profiles, and output waveforms of the LI-RPM and RPM systems were evaluated using a self-produced dynamic phantom. The delay times for the LI-RPM and RPM systems were both 0.1 s for 4 s and 8 s test periods. The corresponding output waveform correlation factors (R 2 ) for the 4 s and 8 s test periods were 0.9981 and 0.9975, respectively. No difference was observed in the dose profiles of the two systems. Thus, the present results indicate that the proposed LI-RPM combined respiratory-gated radiation system has similar properties to the RPM system. However, it offers several advantages in terms of its versatility, including its alignment assistance capabilities for non-coplanar treatments.

We retrospectively evaluated factors affecting the lifespan of schizophrenic patients, who are known to have a shorter life expectancy than healthy people, focusing on the relationship with QT prolongation associated with antipsychotics. In a total of 406 patients who died at Asai Hospital the mean age at death was compared between schizophrenic patients and nonpsychiatric patients. In deceased schizophrenic patients, drug-related factors, hematology results, and electrocardiographic findings for 3 years before death were compared with those for the same period in age-matched surviving schizophrenic patients. In addition, QT values in schizophrenic patients and healthy controls were evaluated by age group. The mean age at death was significantly younger in schizophrenic patients (63.4 +/- 2.63 years) than in nonpsychiatric patients (84.0 +/- 0.57 years) (p<0.001). Bivariate analysis between deceased and surviving schizophrenic patients showed significant differences in QT values at 2 years, 1 year, and 0.5 years before death and in AST and ALT values at 0.5.years before death. The incidence of QT prolongation in deceased schizophrenic patients (52.0%) was about twice as high as that in surviving schizophrenic patients (24.5%). Multiple logistic regression analysis suggested that the proportion of deceased patients was higher when QT intervals were longer and ALT values were relatively higher, even if within the normal range. In both schizophrenic patients and medical checkup examinees, QT values were positively correlated with the age (R2 = 0.9061 and 0.9276, respectively), and QT intervals in schizophrenic patients were significantly longer in the 30- to 70-year age groups. In both schizophrenic patients and medical checkup examinees, QT values were positively correlated with the age, and QT intervals in schizophrenic patients were significantly longer than those in medical checkup examinees in the same age groups. Deceased schizophrenic patients showed significantly longer QT intervals from 2 years before death than age-matched surviving schizophrenic patients. QT prolongation may influence the lifespan of schizophrenic patients, which are shorter than those of nonpsychiatric patients. This highlights the importance of following electrocardiographic findings and hematology results of schizophrenic patients over time.