Objective: Two simple, commercially available and semiquantitative dust mite allergen tests, namely, the Acarex test^® and Mitey Checker^®, were compared using 2 and 10 μg of Der 1 allergen per gram of dust, as evaluated by enzyme-linked immunosorbent assay (ELISA), to clarify which method is better suited for practical use.
Methods: Mite allergen exposure levels of 106 floor, bed and sofa surfaces were evaluated by the Acarex test^®, Mitey Checker^®, and ELISA. A template of 100 cm×100 cm was placed on the same surfaces to identify the examined areas. A dust collection filter was attached to a vacuum cleaner, and the area in the template (1 m²) was vacuumed. Then, to evaluate the other two tests, samples from the two other areas in the template (1 m²) that neighbored each other and did not overlap were vacuumed.
Results: To predict Der 1 levels of 2 μg/g dust or higher, the sensitivity and specificity of the Acarex test^® were 100% and 13.3%, and those of Mitey Checker^® were 91.8% and 71.1%, respectively. To predict Der 1 levels of 10 μg/g dust or higher, the sensitivity and specificity of the Acarex test^® were 50.0% and 96.2%, and those of Mitey Checker^® were 85.7% and 79.5%, respectively. Compared with Der 1<2.0, 2.0-9.9, ≥10.0 (μg/g dust), the percent agreement and kappa of the Acarex test^® were 47.2% and 0.234, and those of Mitey Checker^® were 70.0% and 0.505, respectively.
Conclusion: To evaluate mite allergen exposure level for practical use in Japanese living environments, Mitey Checker^® is better than the Acarex test^® because of its higher sensitivity and specificity.

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Objectives: The aim of this study is to examine the utilities of antenatal care with comprehensive health education qualified in Phnom Penh for the health of mothers and infants during perinatal and postpartum periods. Attention was given to the existing socioeconomic disparities among women in this urban area, and the utilities were discussed irrespective of socioeconomic status.
Methods: A total of 436 pregnant women in an urban area in Phnom Penh were selected using a complete survey in randomly sampled villages and were followed up. Participating in antenatal care with comprehensive health education at least three times was regarded as the use of “qualified antenatal care” during pregnancy. In this study, we investigated the independent associations of the use of qualified antenatal care with the following outcome variables after the adjustment for the influence of socioeconomic variables: postpartum maternal health knowledge, postpartum maternal anemia, low birth weight, and infant immunization.
Results: Of the 314 subjects who completed the follow-up examination, 66.8% used qualified antenatal care during pregnancy. The use of qualified antenatal care was positively associated with postpartum maternal health knowledge (OR=2.38, 95%CI: 1.12–5.05), and reductions in the incidences of postpartum anemia (OR=0.22, 95%CI: 0.05–0.95) and low birth weight (OR=0.06, 95%CI: 0.01–0.39) after the adjustment of the influence of socioeconomic status. The infants born to mothers who used qualified antenatal care had significantly higher coverage of BCG , DPT₁, and DPT₃ immunizations (P<0.001, P<0.001, and P<0.01, respectively), independent of their socioeconomic conditions.
Conclusion: This study shows the solid utilities of qualified antenatal care in Phnom Penh for perinatal health.

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Objectives: In addition to having health-promoting effects, exercise is considered to induce oxidative stress. To clarify whether increased oxygen consumption during exercise induces oxidative stress, we investigated the effects of aerobic exercise and anaerobic exercise on a series of oxidative damage markers.
Methods: One group of subjects performed aerobic exercise and another group performed anaerobic exercise with similar workloads, but with different levels of oxygen consumption. Blood and urine samples were collected before, immediately after, and 3, 9, and 24 h after exercise. Serum uric acid (UA) and creatine phosphokinase were evaluated. As markers of oxidative damage to lipids, proteins and DNA, we evaluated serum 4-hydroxy-2-nonenal, urinary F₂-isoprostanes, serum protein carbonyls, and leukocyte 8-hydroxydeoxyguanosine.
Results: Oxygen consumption was significantly greater during aerobic exercise. Although UA level increased immediately after aerobic exercise and decreased thereafter, UA level did not change after anaerobic exercise. The two types of exercise had significantly different effects on the change in UA level. After anaerobic exercise, the levels of 8-hydroxydeoxyguanosine and 4-hydroxy-2-nonenal significantly increased at 24 h and 3 h, respectively. The levels of creatine phosphokinase and F₂-isoprostanes decreased after exercise. The two types of exercise caused no apparent significant differences in the levels of these biomarkers.
Conclusion: The findings suggest that similar workloads of anaerobic exercise and aerobic exercise induce reactive oxygen species (ROS) differently: aerobic exercise seems to initially generate more ROS, whereas anaerobic exercise may induce prolonged ROS generation. Although more oxygen was consumed during aerobic exercise, the generated ROS did not induce significant oxidative damage. Oxygen consumption per se may not be the major cause of exercise-induced oxidative damage.

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Objective: The relation between daily maximum temperature and mortality rate has a V-shaped pattern; the mortality rate is lowest at a certain temperature, that is, optimum temperature (OT), and the mortality rate increases when the temperature becomes higher or lower than OT. OT is associated with climate, but the relation between OT and long-term average temperature, which is a frequently used index of climate, had an outlier (Okinawa) even in Japan alone. Our objective is to determine the best climate index for OT estimation.
Methods: We obtained death certificate data, meteorological data and population data for Japan from relevant government ministries. All the data obtained were from 1972 to 1995 except for Okinawa’s mortality data (1973 to 1995). Using smoothing spline with the degree of freedom fixed to 6, we computed the OTs for 47 prefectures in Japan. These OTs were exhaustively compared with percentiles of daily maximum, average, and minimum temperatures, along with the long-term average temperature.
Results: Among the candidates of the best climate index, 80 and 85 percentiles of daily maximum temperatures (Tmax80 and Tmax85) showed the highest correlation coefficient with OT (R>0.9, much higher than the R for the long-term average temperature, i.e., 0.63), and the regression models using Tmax80 and Tmax85 best regressed the OT, that is, the difference between the observed OT and the expected OT was smallest when Tmax80 or Tmax85 was used. Unlike previously used average of daily mean temperature, Tmax80 and Tmax85 made Okinawa a nonoutlier. This characteristic is desirable because Okinawa’s being an outlier is due to its maritime climate and the capacity to accommodate a different type of climate may expand the applicability of OT estimation method to wider regions in the world. A direct comparison of OT with Tmax75 to Tmax90 revealed that the difference is smallest for the percentile between Tmax80 and Tmax85.
Conclusion: We considered that a daily maximum temperature between Tmax80 and Tmax85 is the best climate index for estimating OT in Japan.

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Objectives: Recently, perfluorooctanoate (PFOA) has been ubiquitously detected in the environment as well as in human serum. Fluorotelomer alcohols (FTOHs), a precursor of PFOA, undergo biodegradation via several metabolic routes which leads to formation of various biodegradation products. The degradation of FTOHs produces an α,β-unsaturated aldehyde that seems possibly to be electrophilic and may react with cellular macromolecules including DNA.
Methods: We investigated the genotoxicity of three FTOHs (6:2 FTOH, 8:2 FTOH and 10:2 FTOH), PFOA and perfluorooctane sulfonate (PFOS) using the umu test.
Results: The FTOHs, PFOA and PFOS showed no significant increases in β-galactosidase activity at 0−1000 μM in the absence of S9 mix. The results were unchanged by the metabolic activation with S9 mix.
Conclusion: The genotoxicities of FTOHs, PFOA or PFOS are not detectable using the present method, suggesting that they are unlikely mutagens.

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Objectives: We investigated the correlation between changes in body weight and body composition parameters.
Methods: We used the data of 2635 Japanese (40.2±12.2 years) at baseline and at 1-year follow-up from a database of 13522 subjects, which is available at the Okayama Southern Institute of Health in Okayama prefecture, Japan. Body weight, waist circumference at the umbilical level, hip circumference, and body fat percentage were used in the analyses.
Results: Body composition parameters were significantly reduced after 1 year. Changes in body weight significantly correlated with changes in waist circumference, changes in hip circumference, and changes in body fat percentage. A decrease in body weight of 3 kg corresponded to a 3.45 cm decrease in waist circumference in men and a 2.83 cm decrease in that in women.
Conclusion: A decrease in body weight of 3 kg corresponded to an almost 3 cm decrease in waist circumference at the umbilical level in Japanese men and women.

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