ABSTRACT
Objective@#To assess the associations of indoor fine particulate matter (PM2.5) from outdoor and indoor sources with heart rate (HR) and heart rate variability (HRV) in patients with chronic obstructive pulmonary disease (COPD) of Beijing.@*Methods@#A total of 40 male patients in a stable stage of COPD were recruited from a hospital in a panel study in Beijing with 5 consecutive days of measurement for each subject. General information and disease history of the participants from questionnaires were obtained prior to the study. HR and HRV were repeatedly examined using dynamic electrocardiograph. HRV included standard deviation of all NN intervals (SDNN), root mean square of successive differences between adjacent NN intervals (rMSSD), total power (TP) power in the low-frequency band (LF) and the high-frequency band (HF). Iron was used as tracer element to separate indoor-originated PM2.5 and outdoor-originated PM2.5. Mixed-effect models were applied to assess the associations of outdoor-originated PM2.5 or indoor-originated PM2.5 and health effects.@*Results@#The P50 (P25, P75) values of daily indoor PM2.5, indoor-originated PM2.5 and outdoor-originated PM2.5 were 50.9 (26.8, 122.7), 16.0 (1.9, 43.7) and 27.3 (13.5, 61.8) μg/m3, respectively. The mean±SD of concentrations of real-time indoor PM2.5, indoor-originated PM2.5 and outdoor-originated PM2.5 were (61.5±58.8), (25.3±39.1) and (36.2±42.7) μg/m3, respectively. Compared with outdoor-originated PM2.5, indoor-originated PM2.5 had significant associations with HRV and HR. Each 10 μg/m3 increase at 4 h indoor-originated PM2.5 and outdoor-originated PM2.5 moving average was associated with 3.4% (95%CI: -4.7%, -2.1%) and 0.6% (95%CI: -2.0%, -0.8%) reduction in TP (P<0.001). Each 10 μg/m3 increase at 12 h indoor-originated PM2.5 moving average was associated with 7.6% (95%CI: -10.1%, -5.1%), 4.7% (95%CI: -6.7%, -2.7%), 3.3% (95%CI: -4.2%,-2.4%) and 3.0% (95%CI: -4.5%, -1.5%) reduction in HF, LF, SDNN and rMSSD, respectively. Each 10 μg/m3 increase at 12 h outdoor-originated PM2.5 moving average was associated with 0.7% (95%CI: -2.7%, -1.4%), 0.2% (95%CI: -1.9%, 1.4%), 0.7% (95%CI: -1.4%, -0.1%) and 0.2% (95%CI: -1.3%, 0.9%) reduction in HF, LF, SDNN and rMSSD, respectively (P<0.001). Each 10 μg/m3 increase at 8 h indoor-originated PM2.5 and outdoor-originated PM2.5 moving average was associated with 0.7% (95%CI: 0.4%, 1.0%) and 0.4% (95%CI: 0.2%, 0.6%) increase in HR.@*Conclusion@#Exposure to indoor-originated PM2.5 was more strongly associations with HRV indices and HR compared with outdoor-originated PM2.5 in male COPD patients.
ABSTRACT
In this study, the time-dependent changes on dynamic computed tomograph (CT) of radiation-induced liver injury in gastric cancer patients was examined. The CT images of 52 gastric cancer patients who had received chemoradiotherapies were reviewed on the PACS system. Dynamic CT scan was performed in all the subjects. Our results showed that 18 patients were found to have radiation-induced liver injury. The CT findings of radiation-induced liver injury in gastric cancer patients tend to show up one month after radiation treatment. The damaged area was of low density on all three phases, and then it was enhanced on portal vein phase or delay phase. The focal radiation reaction of liver without basic disease vanished 9-11 months later after treatment. We are led to conclude that dynamic CT is of help in the diagnosis of CRT-induced liver injury, and it may be the method of choice for following up the whole course of the CRT-induced liver injury, i.e., form hepatic damage to healing. The classification of CT findings we recommend can avoid the influence of technological factors, and thereby serve as a better guide for treatment of CRT-induced liver injury.