The aim of this study was to investigate whether changes in urinary 8-hydroxydeoxyguanosine (8-OH-dG), an oxidative stress indicator, occur or not, and how psychological reactions change, after one night of sleep deprivation (SD) and after 7 hour recovery sleep opportunities during three recovery days. Twenty healthy subjects participated in this study. We measured their urinary 8-OH-dG levels and psychological reactions using the Profile of Mood States (POMS) for 5 days: on the baseline day, the post-vigil day, and on 3 recovery days after SD. The urinary 8-OH-dG levels and subscale scores of POMS were analyzed using repeated analysis of variance (ANOVA). In the psychological reactions, the values of Vigor on the post-vigil day and 2nd recovery day were significantly lower than on the baseline day. Fatigue and confusion on the post-vigil day were significantly higher than on the baseline day, and on the 1st and 2nd recovery days were relatively higher compared to the baseline day but returned to baseline level on the 3rd recovery day. The urinary 8-OH-dG levels did not change significantly after SD, on the postvigil day or on the 3rd recovery days. These results suggest that the effect of one night of SD on psychological reactions continued for 2 or 3 days, and SD might not influence urinary 8-OH-dG levels despite marked changes in psychological reactions.

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To investigate the exon/intron structure of the Artemia trehalase gene, four overlapping clones were isolated from a genome library derived from an inbred strain of crustacean Artemia franciscana, and a 49kb genetic area was re-constructed. The re-constructed area contained eight exons corresponding to the trehalase cDNA sequence that we had previously reported [1]. Comparative analysis of the Artemia trehalase gene with other animal trehalase genes revealed the existence of conserved exon/intron boundaries among different phyla. Comparison of the 5'UTR region of trehalase mRNA obtained by the 5'RACE method with the trehalase genes indicated the existence of a novel exon/intron boundary in the region designated "Exon I". Surprisingly, a part of a mitochondrial ribosomal protein gene (MRP-S33) was found to be inserted in the 5'UTR region of the trehalase gene. This sequence had the same polyadenylation signal that the Artemia MRP-S33 cDNAs did. Using the 3'RACE method, it was demonstrated that the poly (A) additional signal is still functional and that the chimeric mRNAs composed of the 5'UTR of the trehalase mRNA and of the 3'end derived from the MRP-S33 gene are transcribed.

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Recently in Korea, the treatment of asbestos-containing materials (ACM) in building has emerged as one of the most important environmental health issues. This study was conducted to identify the distribution and characteristics of ACM and airborne asbestos concentrations in industrial buildings in Korea. A total of 1285 presumed asbestos-containing material (PACM) samples were collected from 80 workplaces across the nation, and 40% of the PACMs contained more than 1% of asbestos. Overall, 94% of the surveyed workplaces contained ACM. The distribution of ACM did not show a significant difference by region, employment size, or industry. The total ACM area in the buildings surveyed was 436,710㎡. Ceiling tile ACM accounted for 61% (267,093㎡) of the total ACM area, followed by roof ACM (32%), surfacing ACM (6.1%), and thermal system insulation (TSI). In terms of asbestos type, 98% of total ACM was chrysotile, while crocidolite was not detected. A comparison of building material types showed that the material with the highest priority for regular management is ceiling tile, followed by roof, TSI, and surfacing material. The average airborne concentration of asbestos sampled without disturbing in-place ACM was 0.0028 fibers/cc by PCM, with all measurements below the standard of recommendation for indoor air quality in Korea (0.01 fibers/cc).

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The purpose of this study was to examine the effect of smoking on a video-assisted thoracic surgery lobectomy in 83 male patients with clinical stage I primary lung cancer. Forty-two patients who had smoked until 1 week to 2 months before surgery (Smoker group) were retrospectively compared with 35 ex-smokers who had continued smoking cessation for 15 years on average and 6 non-smokers (Non-& Ex-smoker group), regarding the demographic, perioperative, histopathologic and outcome variables. Except for age, cigarette consumption and comorbid chronic obstructive pulmonary disease (COPD), the two groups showed no differences in the demographic, operative and histopathologic variables. The smoker group demonstrated a significantly younger age (P=0.0497), more cigarette consumption (P=0.0086), more COPD (P=0.0004), longer chest tube drainage (P=0.0451), longer length of hospitalization (P=0.0181) and more postoperative complications (P=0.0278) than the ex- and non-smoker groups. No mortality was observed in either group. The two groups had comparable survival rates. The results indicate that an early cessation of smoking is desirable even when a video-assisted thoracic surgery lobectomy is performed.

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The values for the lowest workload for submaximal exercise testing with bicycle ergometers currently recommended by the Japan Medical Association and the American College of Sports Medicine (ACSM) is 25-50-75-100W, depending on the gender and fitness of the individual. However, some women are unable to complete the test suite before reaching a steady state in the third stage. The purpose of the present study is to explore this problem and identify possible solutions. Using a multi-stage incremental ergometer test with the workload between 20W and 120W, 22 (26.2%) of the 84 adult female subjects had predicted workloads of less than 75W as the criterion for terminating the submaximal test, based on the 70% heart rate reserve (HRR) method. Moreover, 29 of the 84 female subjects (34.5%) reported the workload as being "Hard" (>15 on the Borg scale) at workloads of 75W or less in tests in which the rating of perceived exertion of "Hard" is the criterion for terminating the test. Of the 84 subjects, 19 (22.6%) reported this rating at loads of 60W or below. However, only two subjects (2.4%) reported this rating at 50W or below. Therefore, it may be more useful and effective to use a lower workload value as an option (for example, a third load of 60W), due to the typically slight build of women. To set the protocol, on the other hand, we generally account for the subject's body weight when predicting the load for 70% HRR. In our group of subjects, the correlation between the load at 70% HRR and body weight was only r=0.269. However, when we used fat-free mass (FFM) instead of body weight, the correlation proved stronger (r=0.404). Therefore, it is suggested that using FFM in place of body weight can improve the precision in predicting the appropriate workload when setting the protocol for submaximal exercise testing using bicycle ergometers.

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Histamine is synthesized from L-histidine by histidine decarboxylase and is involved in a variety of physiologic responses, such as inflammation, type I allergy, gastric acid secretion and neurotransmission. In the arteriosclerotic lesions, histamine produced by macrophage-derived foam cells acts on smooth muscle cells, endocrine cells and inflammation cells through the specific histamine receptors and regulates the expression of many molecules concerned with inflammatory reaction. A regulatory system of chronic inflammatory reaction by the histamine network is involved in the formation and development of arteriosclerosis.

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The required number of dedicated industrial physicians has been enacted by the Ministry of Health, Labour and Welfare in Japan. However, the number of workplaces requiring an appointment of industrial physicians is unknown, because of the lack of official publication from the Ministry of Health, Labor and Welfare. The Bureau of Statistics in the Ministry of Internal Affairs and Communications has published the Establishment and Enterprise Census. Based on this statistical data, we estimated the minimal necessary number of dedicated industrial physicians in Japan. There are 1,228 workplaces where 1,000 workers or more are regularly employed. Considering that the number of hazardous workplaces where 500-999 workers are regularly employed is around 1,500, it is estimated that at least 2,000-2,500 dedicated industrial physicians are required in Japan.

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The purpose of this study was to evaluate the program and teaching methods of the occupational health nursing practicum in order to enforce students' learning experience in the clinical practice. Self-evaluation sheets graded from levels 1 to 4 were from 63 students, and statistical analysis was performed in relation to their performance levels. The results of the analysis of 63 students' performance sheets indicated that the students achieved 3 points above average in all 14 course objectives. Scales analysis of the students' evaluation sheets also revealed that students' achievement levels were lower at the Industrial Health Organization in comparison with those at the industrial enterprises. To make students' practice more valuable, students' assessment skills of the workers and working environment should be emphasized in the classroom teaching and experience of learning at the laboratory. Moreover, the course objectives should be sufficiently linked to the practice areas in order to differentiate between the features of the Health organizations and enterprises.

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