Airborne microorganisms in the indoor environment of Syowa Station in Antarctica

Airborne bacterial and fungal numbers in the buildings of Syowa Station in Antarctica were examined for 9 months in 2001. The number of bacteria or fungi was less than 20 or 70/m^3 in the dining room and washroom. The average number of bacteria or fungi was less than 1/50 or 1/5 of those in Japan and Europe, respectively, and remained constant regardless of season. The number of airborne microorganisms appeared to depend on drying of the indoor environment by the use of air-conditioners

Regional Differences of Serotonin-Mediated Synaptic Plasticity in the Chicken Spinal Cord With Development and Aging

Previous studies in our laboratory /3,17/ have demonstrated that serotonin (5-HT) appears to have a trophic-like effect in enhancing synapse formation and maintenance in both the developing and the adult central nervous system. In the present study, we focused on age-related changes in the density of the axosomatic and axodendritic synapses and the number of 5-HT-positive fibers in the chicken spinal cord, with special reference to differences between the ventral (laminae VII and IX) and the dorsal (lamina I) horn. At 1 week posthatching (PIW), a transient overproduction of synapses and 5-HT-immunoreactive fibers occurred in lamina IX; all parameters had returned to their initial levels by 1 month post-hatching (PIM). The density of synapses further decreased by about 40% between P6M and P2Y (2 years posthatching). Although the magnitude of the transient increase in lamina VII was less than that in lamina IX, the changing pattern of the synapses and the 5-HT-positive fibers was similar in both regions. In the ventral horn, thin 5-HT-positive fibers were most prominent at P1W and then decreased with development; thin 5-HT-positive fibers were still found at P6M but had almost disappeared by P2Y. By contrast, at P2Y the density of the synapses and the 5-HT-positive fibers in the dorsal horn was even higher than that of younger animals

Suppression Effect of Radiated Emission from Twisted Pair Wires with Ferrite Core

Telecommunications signal emissions from unshielded twisted pair (UTP) cable should be suppressed to maintain EMC of telecommunication systems. This paper describes the suppression effects of the ferrite cores which are installed on the UTP cable. Twisted pair wire with ferrite core was modeled by 4-port network to evaluate suppression effect. Parameters of the networks which are constructed with UTP cable or ferrite core with wires were determined from calculation and measurement. Using the networks, the common-mode current distribution on the cable was obtained, and emitted electric field strength was calculated from the distribution. The emission suppression effect was obtained from the result, and the results were almost agreed with measured value. The calculation results suggest that 1) the ferrite cores should be arranged side by side, 2) these should be placed near the signal supply end of the cable.2003 IEEE Symposium on Electromagnetic Compatibility, August 18-22, 2003, Boston, MA, US

Household income relationship with health services utilization and healthcare expenditures in people aged 75 years or older in Japan: A population-based study using medical and long-term care insurance claims data

Background: This study aimed to determine whether there are disparities in healthcare services utilization according to household income among people aged 75 years or older in Japan.Methods: We used data on medical and long-term care (LTC) insurance claims and on LTC insurance premiums and needs levels for people aged 75 years or older in a suburban city. Data on people receiving public welfare were not available. Participants were categorized according to household income level using LTC insurance premiums data. The associations of low income with physician visit frequency, length of hospital stay (LOS), and medical and LTC expenditures were evaluated and adjusted for 5-year age groups and LTC needs level.Results: The study analyzed 12,852 men and 18,020 women, among which 13.3% and 41.5%, respectively, were categorized as low income. Participants with low income for both genders were more likely to be functionally dependent. In the adjusted analyses, lower income was associated with fewer physician visits (incidence rate ratio [IRR] 0.90; 95% confidence interval [CI], 0.87–0.92 for men and IRR 0.97; 95% CI, 0.95–0.99 for women), longer LOS (IRR 1.98; 95% CI, 1.54–2.56 and IRR 1.42; 95% CI, 1.20–1.67, respectively), and higher total expenditures (exp(β) 1.09; 95% CI, 1.01–1.18 and exp(β) 1.09; 95% CI, 1.05–1.14, respectively).Conclusions: This study suggests that older people with lower income had fewer consultations with physicians but an increased use of inpatient services. The income categorization used in this study may be an appropriate proxy of socioeconomic status

Survival effect of PDGF-CC rescues neurons from apoptosis in both brain and retina by regulating GSK3β phosphorylation

Platelet-derived growth factor CC (PDGF-CC) is the third member of the PDGF family discovered after more than two decades of studies on the original members of the family, PDGF-AA and PDGF-BB. The biological function of PDGF-CC remains largely to be explored. We report a novel finding that PDGF-CC is a potent neuroprotective factor that acts by modulating glycogen synthase kinase 3β (GSK3β) activity. In several different animal models of neuronal injury, such as axotomy-induced neuronal death, neurotoxin-induced neuronal injury, 6-hydroxydopamine–induced Parkinson’s dopaminergic neuronal death, and ischemia-induced stroke, PDGF-CC protein or gene delivery protected different types of neurons from apoptosis in both the retina and brain. On the other hand, loss-of-function assays using PDGF-C null mice, neutralizing antibody, or short hairpin RNA showed that PDGF-CC deficiency/inhibition exacerbated neuronal death in different neuronal tissues in vivo. Mechanistically, we revealed that the neuroprotective effect of PDGF-CC was achieved by regulating GSK3β phosphorylation and expression. Our data demonstrate that PDGF-CC is critically required for neuronal survival and may potentially be used to treat neurodegenerative diseases. Inhibition of the PDGF-CC–PDGF receptor pathway for different clinical purposes should be conducted with caution to preserve normal neuronal functions