Activation of NADPH oxidase in Alzheimer's disease brains

The present study is the first to show that superoxide (O(-)(2)) forming NADPH oxidase is activated in Alzheimer's disease (AD) brains by demonstrating the marked translocation of the cytosolic factors p47-phox and p67-phox to the membrane. In conjunction with a recent in vitro study showing that amyloid beta activates O(-)(2) forming NADPH oxidase in microglia, where these phox proteins are localized in this study, the present results suggest that, in AD, NADPH oxidase is activated in microglia, resulting in the formation of reactive oxygen species which can be toxic to neighboring neurons in AD.

Quantum phase transitions in the shastry-sutherland model for SrCu2(BO3)(2)

We investigate quantum phase transitions in the frustrated antiferromagnetic Heisenberg model for SrCu2(BO3)(2) by using the series expansion method. It is found that a novel spin-gap phase, adiabatically connected to the plaquette-singlet phase, exists between the dimer and the magnetically ordered phases known thus far. When the ratio of the competing exchange couplings alpha( = J'/J) is varied, this spin-gap phase exhibits a first- (second-) order quantum phase transition to the dimer (the magnetically ordered) phase at the critical point alpha(c1) = 0.677(2) [ alpha(c2) = 0. 86(1)]. Our results shed light on some controversial arguments about the nature of quantum phase transitions in this model.

Does job stress affect injury due to labor accident in Japanese male and female blue-collar workers?

To clarify whether job stressors affecting injury due to labor accidents differ between Japanese male and female blue-collar workers, the Job Content Questionnaire (JCQ), assessing dimensions of job stressors based on the demand-control-support model, was applied to 139 blue-collar workers in a manufacturing factory. Of them, 24 male and 15 female workers suffered from injuries at work. In the female workers with the experience of work injury, the job demand score and job strain index (i.e., the ratio of job demand to job control) of the JCQ were significantly higher and the score of coworker support was significantly lower, than those in the female workers without the experience. High job demand (or, high job strain and low coworker support) was significantly related to work injury in all the female workers. Between the male workers with and without work injury, however, there was no significant difference in any job stressors. This pilot study suggests that high job strain (specifically, high job demand), as well as low coworker support, are important factors affecting work injury in Japanese female blue-collar workers. Further research with a large number of male blue-collar workers will be required to seek other factors that may be associated with work injury.

Lumbopelvic lordosis and pelvic balance on repeated standing lateral radiographs of adult volunteers and untreated patients with constant low back pain

STUDY DESIGN

Twenty volunteers and 20 patients with no prior spine surgery had two standing lateral radiographs taken, on the average, 66 months apart and 2 weeks apart, respectively.

OBJECTIVES

To first determine the reliability of the measurement techniques used, and then the longitudinal variation between radiographs for the sagittal spinopelvic alignments measured in two stable populations, the one manifesting no back symptoms (volunteers) and the other showing no changes in symptoms (patients). Pelvic morphology also was assessed quantitatively, and significant correlations for the measurements were studied.

SUMMARY OF BACKGROUND DATA

There are no published studies on longitudinal variation for measurements of sagittal spinal alignments in asymptomatic control subjects or untreated patients with stable back problems. It may be helpful to know not only how much variation in alignments can be expected between radiographs of the same individual, but also which measurements and measurement techniques offer the greatest clinical reliability and application.

METHODS

Each patient in this study reported mechanical type low back pain that was constant in location and character as well as clinically consistent with symptomatic degenerative lumbar disc disease. Each patient and volunteer had 36-inch-long lateral radiographs taken of the entire thoracic and lumbar spine, which included the pelvis. After intervening periods of 1 to 4 weeks (patients) and 5 to 6 years (volunteers), a second radiograph was taken for comparison. Two observers made 24 different measurements on the radiographs including determinations for lumbopelvic lordosis, pelvic balance, and pelvic morphology using the pelvic radius technique. Reliabilities, longitudinal variations, and correlations for the measurements were compared.

RESULTS

The most reliable measurements were for pelvic morphology, pelvic balance, and regional lumbopelvic lordosis by the pelvic radius technique. Pelvic morphology was the most constant measurement between individual radiographs. Pelvic morphology and total lumbosacral lordosis were dependent measurements that were complementary in determining total lumbopelvic lordosis. Lumbopelvic lordosis and pelvic balance also had strong correlation, whereas lumbosacral lordosis and pelvic balance were independent measurements.

CONCLUSIONS

The pelvic radius technique is recommended for evaluating lordosis to the pelvis because this approach provided not only good measurement reliability on standing radiographs for lumbopelvic lordosis, but also determination of pelvic balance over the hips and the option to assess pelvic morphology quantitatively. Lumbopelvic lordosis and pelvic balance were strongly correlative. This finding, along with higher reliability and lower longitudinal variation on repeated radiographs, indicated greater clinical application for these specific measurements.

Decrease of suppressor-inducer (CD4+ CD45RA) T lymphocytes and increase of serum immunoglobulin G due to perceived job stress in Japanese nuclear electric power plant workers

To clarify the effects of perceived job stress on the immune system, a cross-sectional study was conducted in 116 male Japanese workers of a nuclear electric power plant (age, 20 to 39; mean, 31 years). Perceived job stress, i.e., psychological job demand, job control, worksite social support, and job strain, was assessed by means of the Japanese version of the Job Content Questionnaire. The job strain score was calculated as the ratio of the job demand score to the job control score. Blood samples were taken from all workers, and numbers of T and natural killer cell subpopulations, B lymphocytes, total lymphocytes and white blood cells, and serum concentrations of immunoglobulins (IgG, IgM, IgA, IgE and IgD) in their blood were measured. The workers were divided into higher and lower strain groups according to their job strain scores. The number of CD4+ CD45RA+ T lymphocytes in the higher strain group having the job strain score of 0.5 or more (41 workers) was significantly smaller than that in the lower strain group having the score of less than 0.5 (75 workers). In contrast, the serum IgG concentration in the former group was significantly higher than that in the latter group (analysis of covariance with age and smoking as covariates). Also, the numbers of total CD4+ T and total T (CD3+) lymphocytes and of white blood cells in the former group were significantly smaller than those in the latter group. After controlling for age and smoking by the partial correlation coefficient in all 116 workers, the number of CD57+ CD16+ natural killer cells was inversely correlated with job demand and with job strain; the number of CD8+ T lymphocytes was positively correlated with worksite social support; and serum IgG and IgM concentrations were positively correlated with job strain. It is suggested that higher job strain decreases the number of CD4+ CD45RA+ T lymphocytes in male Japanese workers but increases serum IgG concentrations.

[Evaluation of the operation of supporting programs for social activity of the elderly by city, town, village governments in Japan]

OBJECTIVES

The aim of this study is to clarify the operative situation of the supporting programs for social activity of the elderly by city, town, village governments in 1997.

METHODS

We conducted a study of 3,255 of cities, towns and villages in Japan using a mailed questionnaire, which had been developed to assess the activities of supporting programs for social activity of the elderly. The questionnaire asks government officers whether they had each of the 33 programs in 1997. Each one of these programs belongs to one of the four different aspects of social activities: 1. employment, 2. social participation/volunteering, 3. education/training, 4. individual activities. For each program, the frequency of regions having the program were counted in total, as well as for each of four levels on governments scale: 1. ordinance-designated city, 2. city, 3. town, 4. village. The number of programs operated by the municipality were also evaluated. The main results were as follows One thousand six hundred (49.2%) of cities, towns and villages responded to our questionnaire. 1. Four programs, the promotion of clubs for elderly people, class/lecture meetings for the elderly, sporting events/athletic meetings for the elderly, and a respect-for-age congratulatory gift/money, were put into operation by over 80% of cities, towns and village governments. 2. The number of programs in total or for each of the three aspects of social activities except for social participation/volunteering tended to be high for the large scale governments. There were wide gaps in the number of programs among the regions even of the same level of the government scale. 3. The regions having supporting programs for employment consisted mainly of cities. Seventy-five percent of villages had no supporting program for employment.

CONCLUSION

The operational situation of the supporting programs for social activity of the elderly by city, town, village governments was clarified. Furthermore, results obtained by this study can be used for self-assessment of operational situations by municipalities and can contribute to the activation of their supporting programs.

Inverse association of soy product intake with serum androgen and estrogen concentrations in Japanese men

The cross-sectional relationships of soy product intake and serum testosterone, estrone, estradiol, sex hormone-binding globulin, and dihydrotestosterone were examined in 69 Japanese men. Soy product intake was estimated from a semiquantitative food frequency questionnaire. Serum estradiol concentration was significantly inversely correlated with soy product intake (r = -0.32, p = 0.009), and serum estrone concentration was nonsignificantly inversely correlated with soy product intake (r = -0.24, p = 0.05) after controlling for age, body mass index, smoking status, and ethanol intake. Total and free testosterone concentrations were inversely correlated with soy product intake after controlling for the covariates, but these correlations were of border line significance (r = -0.25, p = 0.05 and r = -0.25, p = 0.06, respectively). Similar correlations were observed for these hormones with isoflavone intake from soy products. The data suggest that soy product intake may be associated with the endogenous hormone levels in Japanese men.

Rationality/antiemotionality personality and selected chronic diseases in a community population in Japan

OBJECTIVE

To clarify the relationships of the rationality/antiemotionality (R/A) personality with past histories of seven chronic diseases and current smoking habits in a community population in Japan.

METHODS

A questionnaire survey was conducted of all residents aged 35 years old or over (n = 37,287) in Takayama city, Gifu prefecture, Japan; the response rate was 90.3%. Data from 13,091 males and 14,061 females who completed all relevant questions were analyzed. The subjects were asked to complete an 11-item R/A personality scale developed by Grossarth-Maticek et al. (1985). Past histories of seven major chronic diseases and current smoking habit were also asked in the questionnaire.

RESULTS

Among males, the R/A scale score was significantly lower in those who had stroke, diabetes or allergy than in those who did not. Among females, the R/A scale score was significantly lower in those who had stroke, allergy or stomach cancer than in those who did not. Among females, current smokers had significantly lower R/A scores than non-smokers. After controlling for age, smoking and drinking, the R/A score was significantly and negatively associated with stroke among males and females; it was significantly and negatively associated with diabetes and allergy among males.

CONCLUSION

Our findings are contrary to those observed in Yugoslavia and West Germany, and suggest a cultural difference in the relationship between the R/A personality and disease occurrence.

Sleep problems in white-collar male workers in an electric equipment manufacturing company in Japan

In order to clarify poor sleep habits and prevalence in sleep problems (disturbances) of healthy male white-collar workers and the relationship of these to age and job type, a total of 1,161 Japanese employees of an electric equipment manufacturing company (aged 23 to 59, mean 37 years) were surveyed by means of a mailed questionnaire. The workers were asked about eleven sleep habits. They were also divided into four groups according to age and job type: 23-29 (n = 226), 30-39 (n = 597), 40-49 (n = 225) and 50-59 (n = 113); managerial (n = 209), professional (n = 336), technical (n = 475) and clerical (n = 134). In this study, the sleep problems were defined as who had at least one of the following four poor sleep habits: 1) taking more than 30 minutes to fall asleep, 2) awakening during sleep (ADS) almost every day, 3) early morning awakening (EMA) almost every day, and 4) excessive daytime sleepiness (EDS) at work almost every day. Analyses showed that sleep problems were present in 26.0% of workers; the problems were most serious among workers aged 50 years and more (36.0%) which may be due to a significant increase in the prevalence rate of EMA. The results revealed that sleep problems are common in male white-collar daytime workers. The findings also suggest a need for increased attention to sleep problems in older workers and younger ones with EDS at work.

Green fluorescent protein-transgenic mice: immune functions and their application to studies of lymphocyte development

Green fluorescent protein (GFP) transgenic (GFP+) mice express GFP in most tissues except erythrocytes and hair. Immune responses of GFP+ mouse and their application to studies of lymphocyte development were investigated. Flow cytometric analyses revealed that differentiation patterns of lymphocytes from GFP+ mice are equivalent to those from parental C57BL/6 mice. There was no difference in mature T-cell proliferative ability in response to allogeneic stimulator cells or anti-CD3epsilon stimulation between GFP+ and C57BL/6 mice. Furthermore, the anti-OVA antibody response of GFP+ mice was also the same as that of C57BL/6 mice. Taken together, these results show no immunological differences between GFP+ and C57BL/6 mice. Bone marrow transplantation and in vitro thymus reconstitution experiments were performed in an attempt to apply the GFP+ mice to the analysis of lymphocyte development. When bone marrow cells from GFP+ mice were transplanted. T and B lymphocytes containing GFP developed normally in scid recipients. Next we examined intrathymic T-cell development by hanging drop culture methods. GFP+ and CD4+8+ immature T-cells developed normally from bone marrow cells in the reconstituted thymus. The experimental system using hematopoietic cells from GFP+ mice is a powerful tool for visualizing lymphocyte development.

The hydroxyl radical formation system in polymorphonuclear leukocytes

We studied the hydroxyl radical (OH*)-generating system in polymorphonuclear leukocytes (PMNs). When phenylalanine was incubated with the alpha, beta and gamma fractions prepared from pig polymorphonuclear leukocytes (PMNs) and hydrogen peroxide (H2O2), significant levels of formation of m- and o-tyrosine were observed in the alpha and beta fractions, but not in the gamma fraction. The amount of tyrosine formation per milligram of protein was greater with the beta than with the alpha fraction. Further, when phenylalanine was incubated with alpha or beta fractions with similar myeloperoxidase (MPO) activities in the presence of H2O2, tyrosine formation by the beta fraction was also more effective. Using the beta fraction in which the MPO activity was destroyed by heat treatment, no significant amount of tyrosine was formed. However, with the heat-treated beta fraction and MPO preparations from human neutrophils in the presence of H2O2, the amount of tyrosine formation increased with the addition of increasing amounts of heat-treated beta fraction. Tyrosine formation by the beta fraction in the presence of H2O2 was significantly reduced by OH* scavengers. The above results suggest the existence of an OH*-generating system in which MPO and H2O2 participate in the granules of PMNs and, especially, in specific granules, there may exist some factors that cause more effective OH* generation.

Roles of integrins and CD44 on the adhesion and migration of fetal liver cells to the fetal thymus

Adhesion and migration of mouse fetal liver (FL) cells to the thymus were investigated using cells from green fluorescent protein transgenic (GFP+) mice. FL cells from GFP+ embryos at 12 gestational days (E12) of mice were incubated with 2'-deoxyguanosine-treated fetal thymus lobe (from E14) by thymic repopulation (hanging drop) culture methods. GFP+ cells were observed in the thymus lobe at the end of the repopulation culture period. A large part of the infiltrated cells expressed CD44 until day 2 of culture on a permeable membrane, then lost the expression. CD25 expression was observed from day 1 to day 4. Around day 8, GFP+ cells became both CD4+ and CD8+. The results support the early observation of the sequential expression of CD44, CD25, and CD4/8 during the early stages of thymocyte development. When anti-CD44 mAb was added at the beginning of the repopulation culture period, GFP+ FL cells adhered to the surface of the thymus lobe but did not migrate into the thymus. Pretreatment of the thymus with hyaluronidase or hyaluronate produced results similar to the results of anti-CD44 treatment. On the other hand, the addition of anti-integrin alpha4 mAb inhibited adhesion to the thymus, and almost no GFP+ cells were seen on the surface of the thymus lobe. The data suggest that integrin alpha4 and CD44 play different roles, i.e., integrin alpha4 is required for the adhesion of FL cells to the thymus lobe and CD44 is required for the migration of the cells into the thymus.

Evaluation of a screening program on reduction of gastric cancer mortality in Japan: preliminary results from a cohort study

BACKGROUND

Systematic population-based screening for gastric cancer is widely spread in Japan. However, the case-control study method has been the main method used to evaluate the effectiveness of the screen ing to reduce gastric cancer mortality in Japan.

METHODS

This article presents a population-based cohort study. A questionnaire about lifestyles and dietary habits was distributed to 36,990 residents in a city of Japan. The response rate to the questionnaire was 92.0%. After ineligible responders had been excluded, 24,134 subjects were classified into screened and un screened groups according to their self-reports of participation in the screening the previous year. We followed them up for 40 months and linked resident death records in the city. We compared mortality from gastric cancer and all other causes between the groups by us ing the Cox proportional hazard model.

RESULTS

The follow-up period was 78,156.6 person-years from September 1992 to December 1995. The multivariate relative risks for gastric cancer death of the screened group in comparison with the unscreened group were 0.72 (95% CI 0.31-1.66) among males and 1.46 (95% CI 0.43-4.90) among females.

CONCLUSION

Although our data are preliminary, we were unable to demonstrate a large contribution of the present screening program to decreasing gastric cancer mortality. Further follow-up is needed to in crease the precision.

Depressive symptoms and occurrence of type 2 diabetes among Japanese men

OBJECTIVE

To examine the relationship between depressive symptoms and the incidence of type 2 diabetes.

RESEARCH DESIGN AND METHODS

In 1984, 2,764 male employees of an electrical company in Japan completed a self-administered questionnaire including the Zung Self-Rating Depression Scale (SDS). They were followed for the next 8 years, and 2,380 (86%) responded to the follow-up survey in 1992. During the follow-up survey, occurrence of type 2 diabetes was diagnosed according to World Health Organization criteria.

RESULTS

A total of 41 cases of type 2 diabetes were identified during the 8-year follow-up survey. After controlling for other known risk factors for type 2 diabetes, a proportional hazard analysis indicated that subjects who had moderate or severe levels of depressive symptoms (> or = 48 on the SDS) at baseline had a 2.3 times higher risk of having type 2 diabetes at the follow-up survey than those who were not depressed (< or = 39 on the SDS) (P < 0.05).

CONCLUSIONS

Depressive symptoms may be associated with the onset of type 2 diabetes.

Participation of cytosolic protein phosphatase in regulation of NADPH oxidase in polymorphonuclear leukocytes

Calyculin A, a protein phosphatase inhibitor, enhanced phorbol 12-myristate 13-acetate (PMA)-induced superoxide anion (O2-) production and translocation of the cytosolic NADPH oxidase factor, p47phox, to the plasma membrane in guinea pig polymorphonuclear leukocytes (PMNs). When PMNs were treated with t-(5-isoquino-line-sulfonyl)-3-methyl-piperazine (H-7), a protein kinase C (PKC) inhibitor, after exposure to PMA, inhibition of O2- production and of translocation of p47phox to the membrane fraction in PMA-stimulated PMNs were observed. When calyculin A was added to the PMA-stimulated PMNs after the addition of H-7, O2- production was again observed, and translocation of p47phox to the membrane fraction also occurred. The activity of NADPH oxidase, the amount of p47phox and the level of phosphorylation of p47phox in the membrane fraction prepared from PMA-stimulated PMNs, were reduced by the addition of the cytosol fraction from unstimulated PMNs. These reductions were attenuated by calyculin A. These results indicate that the active form of NADPH oxidase in PMNs can be reconstituted after the active complex of the enzyme has disappeared once, and that one of the mechanisms of regulation of this enzyme activity involves the phosphorylation of p47phox in the cyotosol and dephosphorylation of phosphorylated p47phox in the NADPH oxidase complex by protein kinase and protein phosphatase, respectively.

Differences of genetic effects for the development of allergic diseases in two cities of Japan

BACKGROUND

Differences in the effects of genetic factors on allergic diseases in two areas of the same race within the same country have not been studied with multiple logistic regression.

OBJECTIVE

To determine whether the effects of genetic factors on allergic diseases differ between two areas.

METHODS

A questionnaire provided information about family histories of allergic diseases and environmental factors was distributed to children attending kindergarten, elementary, or junior high school in two Japanese cities: Gifu, with a temperate climate, and Itoman, with a subtropical one. The number of subjects analyzed were 1,243 in Gifu and 1,953 in Itoman. Multiple logistic regression analysis was performed with SAS.

RESULTS

Multiple logistic regression analysis showed that in both cities children of families with allergic histories have significantly higher risk of contracting allergic disease and atopic dermatitis, even after being controlled for environmental factors. In Gifu, in families where both parents suffered from allergy, there was a higher incidence of allergic diseases than when only one of the parents was suffering from it. On the other hand, in Itoman there were no differences of relative risk between paternal history and maternal history.

CONCLUSIONS

We speculated that there are some differences of genetic factors between different areas of the same country, and these differences of genetic effects may influence on the difference of the prevalence of allergic diseases as well as the environmental factors.

Overtime, psychosocial working conditions, and occurrence of non-insulin dependent diabetes mellitus in Japanese men

OBJECTIVES

To ascertain the effects of overtime and psychosocial job conditions on the occurrence of non-insulin dependent diabetes mellitus (NIDDM) in Japan.

DESIGN

An eight year prospective cohort study.

SETTING

An electrical company in Japan.

PARTICIPANTS

In 1984, a mailed questionnaire was sent to industrial workers of an electrical company in Japan. After excluding those who had a history of diabetes mellitus or other chronic diseases, 2597 male respondents were prospectively followed up for the succeeding eight years. Data from 2194 (84%) who were completely followed up were analysed. The occurrence of NIDDM during the follow up period was assessed according to the WHO criteria on the basis of an annual screening programme.

MAIN RESULTS

The age adjusted incidence of NIDDM was significantly higher in those who worked overtime more than 50 hours per month than in those who worked 25 hours or less per month (p < 0.05). It was significantly higher in those who worked with new technology at baseline than in those who did not (p < 0.05). Cox's proportional hazard model indicated that those who worked overtime more than 50 hours per month had 3.7 times higher risk of NIDDM after controlling for known risk factors (p < 0.01) and those who worked with new technology had 2.4 times higher risk of NIDDM (p < 0.05).

CONCLUSIONS

It is suggested that longer overtime and use of new technology are risk factors of NIDDM in Japanese men.

The first Japanese family with Sebastian platelet syndrome

This report describes the first Japanese family diagnosed with Sebastian platelet syndrome. Within this family, a 6-year-old boy and 3 family members on his paternal side demonstrated thrombocytopenia with giant platelets and inclusion bodies in granulocytes, but the additional clinical features of Alport's syndrome occurring in the Fechtner syndrome were lacking. Light microscopy and ultrastructural findings of the leukocyte inclusion bodies distinguished these patients from the May-Hegglin anomaly. This family showed consistently higher levels of platelet-associated IgG (PAIgG), while surface expression of platelet membrane glycoproteins (GPIIb/IIIa and GPIb) and plasma glycocalicin levels were within the normal range. Careful observation of the giant platelet and leukocyte inclusion bodies in blood smears may help the diagnosis of this rare disease entity.

Job stressor-mental health associations in a sample of Japanese working adults: artifacts of positive and negative questions?

To examine whether positive and negative components of mental health were differently related to job stressors and life events, correlational analyses were conducted using data for the GHQ-12 and some scales of the NIOSH Generic Job Stress Questionnaire collected from 765 workers in Japan. Six positive items and six negative items of the GHQ-12 were summed up for positive and negative components of mental health (GHQ-POS, GHQ-NEG). The GHQ-POS was significantly correlated with only positively-oriented job stressors. The GHQ-NEG was significantly correlated with only negatively-oriented job stressors. Most correlations were significantly different between GHQ-POS and GHQ-NEG. This correlation pattern resulted in smaller, but significant, correlations between job stressors and the GHQ-12. These results may reflect "measuring similarity" due to item-wording. Detailed inspection suggested that GHQ-POS and GHQ-NEG, as well as positively- and negatively-oriented job stressors, were not attributable only to positive affectively or negative affectivity, respectively. Work-related events showed higher correlations with all mental health variables than their job stressors' counterparts. For females, mental health variables were seldom correlated with job stressors, but significantly correlated with life events. These results might indicate the superiority of "event-type stress measure" as compared to perceived rating scale in assessing job stressors. Further direction was discussed.

Epidemiology of job stress and health in Japan: review of current evidence and future direction

With the increasing concern about job stress, there is a growing body of literature addressing psychosocial job stress and its adverse effects on health in Japan. This paper reviews research findings over the past 15 years concerning the assessment of job stress, the relationship of job stress to mental and physical health, and the effects of worksite stress reduction activities in Japan. Although studies were conducted in the past using ad-hoc job stress questionnaires, well-established job stressor scales have since been translated into Japanese, their psychometric properties tested and these scales extensively used in recent epidemiologic studies. While the impact of overtime and quantitative job overload on mental health seems moderate, job control, skill use and worksite support, as well as qualitative job demands, had greater effects on psychological distress and drinking problems in cross-sectional and prospective studies. These job stressors also indicated a strong association with psychiatric disorders, including major depression, even with a prospective study design. Long working hours were associated with a higher risk of myocardial infarction, diabetes mellitus and hypertension. There is evidence that the job demands-control model, as well as the use of new technology at work, is associated with higher levels of blood pressure and serum lipids among Japanese working populations. Fibrinolytic activity, blood glucose levels, immune functions and medical consultation rates were also affected by job stressors. It is further suggested that Japanese workers tend to suppress expression of positive feelings, which results in apparently higher psychological distress and lower job satisfaction among Japanese workers compared with workers in the U.S. Future epidemiologic studies in Japan should focus more on a prospective study design, theoretical models of job stress, job stress among women, and cultural difference and well-designed intervention studies of various types of worksite stress reduction.

Effects of mailed advice on stress reduction among employees in Japan: a randomized controlled trial

We conducted a randomized controlled trial (RCT) to examine the effects of mailed advice on reducing psychological distress, blood pressure, serum lipids, and sick leave of workers employed in a manufacturing plant in Japan. Those who indicated higher psychological distress (defined as having GHQ scores of three or greater) in the baseline questionnaire survey (n = 226) were randomly assigned to an intervention group or a control group. Individualized letters were sent to the subjects of the intervention group, informing them of their stress levels and recommending an improvement in daily habits and other behaviors to reduce stress. Eighty-one and 77 subjects in the intervention and control groups, respectively, responded to the one-year follow-up survey. No significant intervention effect was observed for the GHQ scores, blood pressure, serum lipids, or sick leave (p > 0.05). The intervention effect was marginally significant for changes in regular breakfasts and daily alcohol consumption (p = 0.09). The intervention effect was marginally significant for the GHQ scores among those who initially did not eat breakfast regularly (p = 0.06). The study suggests that only sending mailed advice is not an effective measure for worksite stress reduction. Mailed advice which focuses on a particular subgroup (e.g., those who do not eat breakfast regularly) may be more effective.

Development of a screening questionnaire for tobacco/nicotine dependence according to ICD-10, DSM-III-R, and DSM-IV

A 10-item questionnaire (the Tobacco Dependence Screener; TDS) for screening of tobacco/nicotine dependence according to ICD-10, DSM-III-R, and DSM-IV was newly developed. The reliability and validity were assessed in three samples of smokers in Japan. A total of 58 male smokers completed the TDS and the Fagerstrom Tolerance Questionnaire (FTQ), and they were interviewed using the World Health Organization's Composite International Diagnostic Interview (Sample 1). A total of 118 male and 36 female smoking outpatients completed the TDS and the FTQ and provided a breath sample for carbon monoxide measurement (Sample 2). A total of 194 male smokers joined a health education program using a health risk appraisal (HRA) and reported their smoking status and completed the TDS 6 months after receiving the HRA results (Sample 3). The Cronbach's alpha coefficients for the TDS ranged from .74 to .81 among the samples, whereas those for the FTQ ranged from .41 to .64. Receiver operator characteristic analyses indicated that the TDS had a better screening performance for ICD-10, DSM-III-R, and DSM-IV diagnoses than did the FFQ. The TDS score significantly and positively correlated with the severity of the diagnoses, the carbon monoxide levels, number of cigarettes smoked per day, and years of smoking. The TDS score was significantly lower in those who quit smoking than in those who did not quit smoking after the HRA. It is suggested that the TDS is a reliable and useful screening questionnaire for tobacco/nicotine dependence according to ICD-10, DSM-III-R, and DSM-IV.

Mechanisms mediating the vasorelaxing action of eugenol, a pungent oil, on rabbit arterial tissue

The inhibitory actions of eugenol on intracellular Ca2+ concentration ([Ca2+]i) and the contractions induced by excess extracellular K+ concentration ([K+]o) in rabbit thoracic aorta were investigated. Application of excess [K+]o solution (30-90 mM) produced contraction and increased the intensity of the Ca2+ fluorescence signal. Pretreatment with eugenol (> or =0.1 mM) reduced both the amplitude of contraction and the intensity of the Ca2+ fluorescence signal, but the contraction was more strongly affected than the [Ca2+]i. Application of eugenol (0.3 mM) to tissue precontracted by 90 mM [K+]o solution (immediately after the removal of the 90 mM [K+]o solution) slowed the decay of the [Ca2+]i signal, but it did not change the rate of relaxation. Carbonyl cyanide m-chlorophenylhydrozone (10 microM), a mitochondrial metabolic inhibitor, produced a reduction in tension despite a slight increase in [Ca2+]i when applied to muscle precontracted by 90 mM [K+]o solution. These results indicate that eugenol relaxes the rabbit thoracic aorta while suppressing the Ca2+-sensitivity and both the uptake and extrusion mechanisms for Ca2+. To judge from the similarities between its actions and those of metabolic inhibitors, eugenol may produce its actions at least partly through metabolic inhibition.

The Job Content Questionnaire (JCQ): an instrument for internationally comparative assessments of psychosocial job characteristics

Part I discusses the Job Content Questionnaire (JCQ), designed to measure scales assessing psychological demands, decision latitude, social support, physical demands, and job insecurity. Part II describes the reliability of the JCQ scales in a cross-national context using 10,288 men and 6,313 women from 6 studies conducted in 4 countries. Substantial similarity in means, standard deviations, and correlations among the scales, and in correlations between scales and demographic variables, is found for both men and women in all studies. Reliability is good for most scales. Results suggest that psychological job characteristics are more similar across national boundaries than across occupations.