It has been known that strenuous physical exercise causes a rise in several growth factors. The purpose of this study was to investigate the concentration changes of growth factors in serum, plasma and saliva during +Gz exposures. The subjects were 12 healthy volunteers (ten males and two females) without anti-G suit. The +Gz exposure profiles consisted of, in series, a gradual onset run (0.1G･sec1) to the subject’s visual end-point (gray-out/black-out) or loss of consciousness, and rapid onset run (1.0G･sec1) to the subject’s same end-point. Serum, plasma and saliva were collected before, immediately after and 2 hours after the +Gz exposures. The concentrations of vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF) and transforming growth factor-β (TGF-β) were measured using an enzyme-linked immunosorbent assay (ELISA). Significant changes in serum VEGF, PDGF, TGF-β, plasma TGF-β and salivary PDGF were not observed during this study. Plasma VEGF and PDGF were not detectable by using an ELISA method. Results of this study suggest that +Gz exposures had no effect on the expression of growth factors in humans.

抄録全体を表示

Hypobaric hypoxia has been recognized as a significant physiological threat at high altitude. The effects of physical / psychological stress of sustained exposure to hypobaric hypoxia are still unknown. Epstein-Barr virus (EBV) is prevalent in >90% of the world’s population. Several studies have suggested that various stressful events are associated with onset, duration, and intensity of EBV reactivation. The purpose of this study was to evaluate the EBV reactivation in instructors of hypobaric chamber training. Subjects were 5 male instructors on volunteer basis. At least 3 months before the experiment started, the instructors did not engaged in hypobaric chamber trainings. Serum and saliva samples were collected at one day before a hypobaric chamber training (Pre), 2 weeks (2W) and 4 weeks (4W) after the training. Early antigen (EA) antibodies, anti-viral capsid antigen (VCA) and anti-EBV nuclear antigen (EBNA) antibodies were measured in serum samples by using an Enzyme-linked immunosorbent assay. The number of copies of EBV DNA was measured in saliva samples by using a real-time polymerase chain reaction. Apparently, there were no differences between Pre and 2W/4W in our measurements. In one instructor, however, it was interesting to note that the number of EBV DNA copies at 2W/4W were 10-fold higher than Pre. Further studies are required to evaluate the herpesvirus reactivation in instructors of hypobaric chamber training.

抄録全体を表示

To characterize occupational exposures to carcinogenic chemicals in flight line personnel, polycyclic aromatic hydrocarbons(PAHs) were determined in JP-4 fueled aircraft emissions both from F-15J and C-130H. The gasand aerosol-phase PAHs were determined by gas chromatography coupled to mass spectrometry and by high performance liquid chromatography with fluorescence detection, respectively. The results showed differences in aerosol PAHs between both aircrafts. C-130H produced higher concentrations of the aerosol PAHs, including 3 or 4 ring-PAHs, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. In contrast, the F-15J emissions included carcinogenic 5 or 6 aromatic ring- PAHs, benzo(b)fluoranthene, benzo(k)fluoranthene, dibenzo(a,h) anthracene, benzo(ghi)perylene and indeno(1,2,3-cd)pyrene. In the gas-phase, both aircraft emissions mainly included about 0.1ppm of naphthalene, which was below the permissible exposure limits given by Occupational Safety and Health Administration(OSHA).

抄録全体を表示