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N Kawakami

Publications and source records attributed to N Kawakami.

At least 73 records · Page 4Linked to original sources
PubMed1998

Effect of soymilk consumption on serum estrogen concentrations in premenopausal Japanese women.

BACKGROUND: Estrogens have been implicated in the development of breast cancer. Preliminary evidence suggests that consumption of soy products, which contain isoflavones (phytoestrogens), can reduce serum estrogen levels. Our purpose was to determine the effect of soy consumption on serum estrogen levels in premenopausal women by use of a dietary intervention approach. METHODS: Premenopausal Japanese women were randomly assigned to receive either a soymilk-supplemented diet (n = 31) or a normal (control) diet (n = 29). The women in the soymilk-supplemented group were asked to consume about 400 mL of soymilk (containing about 109 mg of isoflavones) daily during a study period that involved three consecutive menstrual cycles. Follicular-phase blood samples were to be obtained in the menstrual cycles preceding (cycle 1) and following (cycle 3) the 2-month dietary intervention. All statistical tests were two-sided. RESULTS: At the end of the study period, estrone and estradiol levels were decreased by 23% and 27%, respectively, in the soymilk-supplemented group and were increased by 0.6% and 4%, respectively, in the control group. The changes for each hormone between the two groups were not statistically significantly different. In the soymilk-supplemented group, menstrual cycle length was increased by nearly 2 days, and, in the control group, it was decreased by approximately 1 day, a difference that was not statistically significant. A subgroup analysis restricted to subjects who provided follicular-phase blood samples on the same day or 1 day apart in menstrual cycles 1 and 3 showed a reduction in serum estrone levels in the soymilk-supplemented group that was of borderline statistical significance (P = .07 for change in serum estrone level in soymilk-supplemented group versus control group). CONCLUSION: Much larger studies will be required to confirm the ability of soy products to reduce serum estrogen levels.

Adult↗
PubMed1998

Association of diet and other lifestyle with onset of menopause in Japanese women.

OBJECTIVES: To evaluate the cross-sectional relationships of dietary and other lifestyle variables to menopause. METHODS: A total of 4186 female residents aged 45-55 in Takayama City, Japan, responded to a self-administered questionnaire (the response rate was 89.3%). Diet in the past year was assessed by semiquantitative food frequency questionnaire. Using the logistic regression model, associations between study variables and menopausal status were estimated in terms of odds ratio (OR). RESULTS: Nulliparity and lower relative weight were significantly associated with menopause after controlling for age (P < 0.05). The association of smoking with menopause was marginally significant after controlling for age (P = 0.06). Higher intakes of fat, cholesterol, and coffee were inversely and significantly associated with later menopause after controlling for age, total energy, parity, menarche age, and relative weight (ORs for the highest tertiles of fat, cholesterol and coffee intakes were 0.78, 0.79, and 0.70, respectively, P < 0.05). The highest tertiles of calcium and soy product intakes were significantly associated with menopause after controlling for the covariates (ORs = 1.25 and 1.42, respectively, P < 0.05), but postmenopausal women who had menopause at later age showed higher calcium intake than those who had menopause at early age. CONCLUSION: Dietary factors appear to be associated with onset of menopause.

Age of Onset↗
PubMed1998

Indication of a protein kinase C-independent pathway for NADPH oxidase activation in human neutrophils.

A potent tyrosine phosphatase inhibitor, pervanadate, induced (i) translocation of the cytosolic NADPH oxidase factors, p47-phox and p67-phox, to the plasma membrane; and (ii) O2- production in human neutrophils. However, the translocation of p47-phox and p67-phox was inhibited by H-7, a protein kinase C (PKC) inhibitor without markedly affecting O2- production in whole neutrophils. Results from the plasma membrane fraction showed that NADPH oxidase activity in neutrophils treated with pervanadate did not vary in the presence or absence of H-7, despite a lower content of p47-phox and p67-phox in H-7-treated neutrophils. These findings suggest that in addition to the well-known PKC-dependent pathway, there may exist another PKC-independent pathway to activate NADPH oxidase in human neutrophils. This pathway involves protein tyrosine phosphorylation but does not seem to necessitate translocation of p47-phox and p67-phox to the plasma membrane.

Enzyme Activation↗
PubMed1998

Isolation and characterization of transposon-induced mutants of Porphyromonas gingivalis deficient in fimbriation.

Fimbriae are considered to be an important virulence factor of Porphyromonas gingivalis. In order to identify genes essential for fimbriation, other than fimA which encodes the major subunit protein of fimbriae, transposon mutagenesis and immunological screening techniques were used to isolate fimbria-deficient mutants. R751::*Omega4, a suicide vector that carries Tn4351, was transferred from Escherichia coli to P. gingivalis by conjugation. Twenty-two independent fimbria-deficient mutants were identified among the resulting transformants. Southern hybridization analysis with pBlue 4351, a transposon-specific probe, and R751 indicated that 45% of the mutants resulted from single transposon insertions and that the remaining 55% of the mutants resulted from cointegration of R751 sequences. Southern hybridization analysis with pUCBg12.1, a probe for the fimA region, indicated that nine of the mutants contained insertions within the 2.5 kb SacI DNA fragment of P. gingivalis that contains fimA, ORF1 (which encodes a 15 kDa protein), and the C-terminal portion of ORF5 (which encodes a 63 kDa protein). Polymerase chain reaction (PCR) analysis and further Southern hybridization analysis indicated that the insertion site(s) for all nine of these mutants was within the fimA gene. Southern hybridization analysis also indicated that the remaining thirteen mutants contained insertions somewhere outside the 10 kb fimA region. Analysis by pulsed field gel electrophoresis (PFGE) revealed that insertions for most of the thirteen mutants mapped to a 300 kb NotI fragment and are located at least approximately 200 kb away from fimA. These results identify genetic loci other than fimA, that are required for fimbriation of P. gingivalis. Future cloning and characterization of these genetic loci should be straightforward since they are now marked by antibiotic resistance genes carried by the transposon.

Bacterial Proteins↗
PubMed1998

Job strain and arterial blood pressure, serum cholesterol, and smoking as risk factors for coronary heart disease in Japan.

OBJECTIVE: To determine the effects of the job demands-control model on arterial blood pressure, serum total cholesterol, and smoking in male daytime and rotating-shift workers in Japan. METHODS: The survey was conducted for all employees of an electrical factory in Japan using a mailed questionnaire concerning three job stressors, i.e., job overload, work-pace control, and work-site social support. A blood sample was taken at the same time. Data on 1703 male daytime workers and 1 173 male rotating-shift workers were analyzed. Multiple logistic regression or analysis of covariance (ANCOVA) were employed to determine the effects of the job stressors on systolic and diastolic blood pressure, serum total cholesterol, and smoking with control for other covariates. RESULTS: Among daytime workers, systolic and diastolic blood pressures were highest in the "high-strain" (i.e., higher job overload + lower work-pace control) group; ANCOVA indicated that a two-way interaction between job overload and work-pace control was significant (P < 0.01). This tendency was not observed among rotating-shift workers. The number of cigarettes smoked per day was greater in groups with lower work-pace control and lower work-site social support among daytime workers (two-way interaction between these two job stressors, P < 0.05); it was greater in groups with lower work-site social support among rotating-shift workers (main effect of work-site social support, P < 0.05). CONCLUSIONS: Our study suggest that job strain as defined in the job demands-control model is associated with increased systolic and diastolic blood pressures in male daytime workers in Japan. Smoking might be affected by lower work-site social support.

Adult↗
PubMed1998

myo-Inositol monophosphatase in the brain has zinc ion-dependent tyrosine phosphatase activity.

1. myo-Inositol monophosphatase (E.C. 3.1.3.25) hydrolyzes inositol monophosphate to form free myo-inositol, the precursor for the inositol phospholipid second-messenger signaling systems. The biochemical properties of the enzyme were examined in detail. 2. The enzyme exhibited significant hydrolytic activity only on phosphotyrosine among physiological substrates tested in the presence of Zn2+ ions in an acidic environment. 3. The enzyme was recognized and immunoprecipitated with polyclonal antibodies developed against the Zn2+-dependent tyrosine phosphatase of bovine brain. 4. These results indicate that myo-inositol monophosphatase exhibits Zn2+-dependent tyrosine phosphatase activity in an acidic environment and has immunological identity with a Zn2+-dependent tyrosine phosphatase.

Acid Phosphatase↗
PubMed1998

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.

Adult↗
PubMed1998

Life-time prevalence and risk factors of tobacco/nicotine dependence in male ever-smokers in Japan.

UNLABELLED: To estimate the life-time prevalence rate of tobacco/nicotine dependence and demographic variables and smoking habits associated with the disorder in male ever-smokers in Japan. DESIGN: A cross-sectional community-based interview study. SETTING: Takayama city, Gifu Prefecture, Japan. PARTICIPANTS: A total of 170 male ever-smokers aged 35 years or older selected randomly from a community in Japan were interviewed. The response rate was 85%. MEASUREMENTS: The WHO Composite International Diagnostic Interview (CIDI) was used to make diagnoses of tobacco/nicotine dependence according t ICD-10, DSM-III-R and DSM-IV. The Fagerstrom Tolerance Questionnaire (FTQ) was also administered and those who had a FTQ score of 7 or above were identified. FINDINGS: The life-time prevalence rates of tobacco/nicotine dependence in male ever-smokers were 42%, 26% and 32% according to ICD-10, DSM-III-R and DSM-IV criteria, respectively; 19% had a FTQ score of 7 or above. The ICD-10 diagnosis was significantly and negatively associated with quitting smoking (p < 0.05). Multiple logistic regression analyses indicated that number of cigarettes per day when they smoked the most was significantly associated with higher life-time risks of the disorder according to DSM-III-R, DSM-IV and Fagerstrom's classification (p < 0.05). The length of cigarette smoked was associated with higher life-time risks of ICD-10 and DSM-IV diagnoses, and years of smoking were associated with higher life-time risks of ICD-10, DSM-III-R and DSM-IV diagnoses (p < 0.05). Younger birth cohorts had higher cumulative rates of the disorder according to DSM-IV (p for trend < 0.05). CONCLUSIONS: Life-time prevalence rates of tobacco/nicotine dependence according to ICD-10, DSM-III-R and DSM-IV in male ever-smokers in Japan were within the range of rates reported in previous US studies; rates of FTQ score of 7 or above were lower. Fagerstrom scores and diagnostic criteria appear to reflect different aspects of dependence.

Adult↗
PubMed1998

Molecular cloning and characterization of aldehyde oxidases in Arabidopsis thaliana.

Using degenerate primers designed by deduced amino acid sequences of known aldehyde oxidases (AO) from maize and bovine, two independent cDNA fragments were amplified by reverse transcription-polymerase chain reaction (PCR). The two corresponding full-length cDNAs (atAO-1 and atAO-2; 4,484 and 4,228 bp long, respectively) were cloned by screening the Arabidopsis cDNA library followed by rapid amplification of cDNA end-PCR. These cDNAs are highly homologous at both the nucleotide and amino acid sequence levels, and the deduced amino acid sequences showed high similarity with those of maize and tomato AOs. They contain consensus sequences for two iron-sulfur centers and a molybdenum cofactor (MoCo)-binding domain. In addition, another cDNA having a sequence similar to that of the cDNAs was screened (atAO-3; 3,049 bp), and a putative AO gene (AC002376) was reported on chromosome 1, which (atAO-4) was distinct from, but very similar to, the above three AOs. atAO-1, 2, 3, and 4 were physically mapped on chromosomes 5, 3, 2 and 1, respectively. These data indicate that there is an AO multigene family in Arabidopsis. atAO-1 protein was shown to be highly similar to one of the maize AOs in respect to a region thought to be involved in determination of substrate specificity, suggesting that they might encode a similar type of AO, which could efficiently oxidize indole-3-acetaldehyde to indole-3-acetic acid (IAA). atAO-1 and atAO-2 genes were expressed at higher levels in lower hypocotyls and roots of the wild-type seedlings, while atAO-3 was slightly higher in cotyledons and upper hypocotyls. The expression of atAO-1 was more abundant in the seedlings of an IAA overproducing mutant (superroot1; sur1) than in those of wild type. atAO-2 and atAO-3 transcripts were rather evenly distributed in these seedlings. A possible involvement of atAO genes in phytohormone biosynthesis in Arabidopsis is discussed.

Aldehyde Oxidoreductases↗
PubMed1998

Etiology of idiopathic scoliosis. Computational study.

A review of the literature on the mechanical aspects of the etiology for idiopathic scoliosis reveals that the buckling hypothesis has been presented as a purely mechanical phenomenon. In an attempt to confirm the buckling hypothesis, a numerical simulation of growth and the resulting buckling phenomena was done by means of finite element analysis. It previously was observed that growth was induced in the T4 to T10 vertebrae. Only the sacrum was assumed to be stationary. From the growth analysis, a deformation process that mitigated thoracic kyphosis was obtained as observed in healthy children during early adolescence. From the buckling analysis, the first to the fourth buckling modes that correspond to the first side bending, first forward bending, first rotation, and second side bending modes were obtained. The shape of the fourth buckling mode (second side bending mode) was in good agreement with the clinical shape. Considering the potential for controlling these modes by posture change, it is concluded that the second bending mode in the coronal plane is one of the most likely etiologic candidates in the mechanics of thoracic idiopathic scoliosis.

Adolescent↗
PubMed1998

Role of endothelium and adventitia on eugenol-induced relaxation of rabbit ear artery precontracted by histamine.

Eugenol (> or = 0.1 mM) inhibited the contractions induced by various stimulants, such as 90 mM extracellular K+ solution ([K+]0), histamine and noradrenaline in the rabbit ear artery. Inhibitory actions of eugenol occurred in a concentration-dependent manner, however, eugenol more dominantly inhibited the histamine-induced contraction than those induced by either 90 mM [K+]0 solution or noradrenaline. Removal of both endothelium and adventitia did not change the inhibitory actions of eugenol on the 90 mM [K+]0- and noradrenaline-induced contractions, however, attenuated those on the histamine-induced contraction. Chlorphenylamine abolished the histamine-induced contraction, but neither cimetidine, ranitidine nor thioperamide modified the eugenol actions on the contractions induced by histamine. Pretreatment with nitric oxide syntheses inhibitor NG-nitro-L-arginine (LNNA; 100 microM), but not soluble guanylate cyclase inhibitor methylene blue (MB; 10 microM), prevented endothelium/adventitia-dependent augmentation of the eugenol-induced relaxation on the histamine-induced contraction. When an intact tissue, but not an endothelium/adventitia-denuded tissue, was placed at the up-stream close to the other denuded preparation (test preparation), histamine-induced contraction observed in the test preparation tended to be augmented. Similarly, eugenol-induced relaxation was also augmented by the same treatment. Eugenol (0.3 mM) inhibited the excitatory junction potentials (EJPs) without hyperpolarization of the membrane. However, a high concentration of eugenol (1 mM) slightly hyperpolarized the membrane (ca. 5 mV). No transient enhancement of amplitude of EJP was recorded. These results suggest that eugenol may inhibit the histamine-induced muscle contraction directly, and the inhibition is augmented by the adventitia and endothelium partly by vasoactive substances, which were released from the adventitia/endothelium-derived substances in rabbit ear artery.

Animals↗
PubMed1998

Prevalence of chronic fatigue syndrome in a community population in Japan.

In order to know the prevalence of chronic fatigue syndrome (CFS) in a community population in Japan, we analyzed data from a population-based interview survey. Two cases out of 137 respondents experienced chronic fatigue during a period of nine months, suffered from 50% or more reduction of daily activity due to fatigue and had no other physical or psychiatric diagnosis. Both of the two cases fulfilled the 1994 Centers for Disease Control (CDC) criteria and the British criteria. The point and nine-month prevalence rates of CFS were both 1.5% (95% confidence intervals, 0.4-5.2%). None fulfilled the 1989 CDC criteria for CFS. The prevalence rate of CFS was higher than those in previous studies in the Western countries, suggesting a need for future research on cross-cultural differences in the definition, prevalence and symptomatology of CFS.

Adolescent↗
PubMed1998

Effects of passive smoking on serum levels of carotenoids and alpha-tocopherol.

To evaluate the effects of passive smoking identified by urine cotinine on serum carotenoids and alpha-tocopherol, we categorized 124 residents in a rural city of Japan into 4 groups by their urine cotinine/creatinine (Cot/Cr) ratio (u.d. (undetectable); low (0-50 ng/mg); moderate (50-120 ng/mg); high (> 120 ng/mg)) and compared the serum carotenoids and alpha-tocopherol levels among these groups. We identified passive smoking by low Cot/Cr ratio level. After controlling on related factors, men with low Cot/Cr ratio showed significantly lower serum zeaxanthin/lutein levels than men with u.d. Cot/Cr ratio. The difference was still marginally significant after excluding self-reported current smokers from the low Cot/Cr group. It is suggested that low level exposure to tobacco smoke, which has been reported to be equivalent to that for passive smokers, could be associated with decreased serum zeaxanthin/lutein levels in men.

Aged↗
PubMed1998

Reliability and validity of a questionnaire for assessment of energy expenditure and physical activity in epidemiological studies.

A self-administered physical activity questionnaire (PA-questionnaire) was developed to assess daily energy expenditure and weekly physical activity in epidemiological studies. The Calorie Counter method (CC-method) was administered to 49 male and 32 female volunteers aged 18-64 years, on 7 consecutive days; after the measurement, the subjects were asked to complete the PA-questionnaire (validation study). The PA-questionnaire was completed by 95 males and 119 females (aged 35-73 years) twice with one-year interval (reliability study). The validation study showed that the mean daily energy expenditure estimated by the PA-questionnaire was slightly and significantly (4.5%) lower than that determined by the CC-method for males (p < 0.05); while no significant difference was observed for females (p > 0.05), mean weekly physical activities were similar between the PA-questionnaire and CC-method in males and females. Daily energy expenditures by the two methods strongly correlated with each other: r = 0.56 (p < 0.001) in males and r = 0.67 (p < 0.001) in females. Weekly physical activities by the two methods also strongly correlated with each other: r = 0.68 (p < 0.001) in males and r = 0.69 (p < 0.001) in females. The reliability study indicated that the Pearson's correlation coefficients between two assessments of daily energy expenditure and weekly physical activity over one-year ranged from 0.37 to 0.62 (p < 0.001). These data indicate that the PA-questionnaire has adequate levels of validity and test-retest reliability in assessment of daily energy expenditure and weekly physical activity in epidemiological studies.

Adult↗
PubMed1998

Associations of individuals' health-related behavior with their own or their spouses' smoking status.

BACKGROUND: Many studies indicated that smokers have poor health habits such as high alcohol consumption and imbalanced nutrient intakes. These habits could affect the health-related behavior of smokers' families. METHODS: To investigate the relationship between an individual's health-related behavior (nutrient intakes and participation in cancer screening) and their spouses' smoking status, we analyzed data collected using a self-administered questionnaire during a cohort study. We compared nutrient intakes and cancer screening participation rates between subjects grouped according to their spouses' smoking status, using a multivariate linear regression model to adjust for each subject's age and alcohol consumption. RESULTS: There was an association between husbands' and wives' smoking status (never and current only). Poor micronutrient intakes and cancer screening participation rates were associated with both the subjects' and their spouses' smoking habits. This tendency was most apparent among male smokers and nonsmoking women. However, among nonsmoking men and female smokers, there were no statistically significant differences between groups classified according to their spouses' smoking status. CONCLUSION: Spouses' smoking habits were associated with poor health-related behavior in their partners.

Adult↗
PubMed1998

Cardiovascular fitness, physical activity and selected coronary heart disease risk factors in adults.

BACKGROUND: The aim was to investigate the associations between cardiovascular fitness and physical activity, and their relationship to selected coronary heart disease (CHD) risk factors. METHODS: This was a cross-sectional study for one week. All participants were Japanese living in the City of Toyota, Japan. Two hundred and twenty-two healthy Japanese (104 men and 118 women), with ages between 20 and 62 years old. Cardiovascular fitness (VO2max) was measured by a progressive submaximal bicycle ergometry test. Physical activity was estimated by an accelerometers attached to the subject's waist for one week, CHD risk factors included blood pressure, fasting levels of blood lipids, and apolipoprotein concentrations. RESULTS: Cardiovascular fitness and physical activity were positively related (r = 0.41 in men and 0.65 in women). For both genders, Pearson coefficients as well as age-adjusted partial correlations indicated that fitness was more closely linked to CHD risk factors than activity was. Also, CHD risk factors were analyzed by three groups of fitness and activity levels in both genders, which indicates that subjects who are physically fitter and/or more active tend to have better CHD risk profiles. CONCLUSIONS: As favorable CHD risk profile was related to cardiovascular fitness, but not to physical activity in both genders, it can be concluded that fitness may be a more important independent predictor for CHD risk factors than activity measured by accelerometer over one week.

Adult↗
PubMed1998

[Assessment method for supporting programs for social activities of the elderly by city, town and village governments in Japan].

OBJECTIVES: The authors developed a questionnaire to assess the activities of supporting programs for social activities for the elderly conducted by city, town and village governments, based on the number of such programs. This study aims to examine the validity of the questionnaire. METHODS: We conducted a study of 145 cities, towns and villages from two prefectures in Japan using the questionnaire. The questionnaire asks government officers whether they had each of 32 programs, and the number of programs in total, as well as each of four domains of social activities (i.e., employment, social participation/volunteering, education/training, individual activities) were calculated. They were also asked to classify each of the programs into one of four domains of social activity to which the programs were most related; they were asked to rate how active the programs were for each domain in their community. To examine the validity of the questionnaire, the following indicators were assessed: (1) proportion of reported programs which were not covered by the questionnaire; (2) concordance of classification of programs into four domains of social activity with those judged by government officers; (3) correlations between number of programs and self-rated activity levels by government officers; and (4) correlations of number programs with characteristics of cities, towns or villages. RESULTS: The results indicated that the list of programs covered most of the programs. Proposed classification of programs into four domains of social activities which they are most related to agreed with judgments by officials. The number of programs positively correlated with self-rated activity levels by officers for employment and education/training domains in both prefectures; and for social participation/volunteering and individual activities in one of the prefecture. The numbers of programs for employment of the elderly positively correlated with the total population of the community, number of staffs, proportion of people employed in the tertiary industries and total budget for social welfare of the elderly; it negatively correlated with proportion of people employed in the primary industries. CONCLUSION: It is suggested that the list of programs in the questionnaire is applicable and assessment based on the number of programs by four social activity domains is valid to some extent in either prefecture. The questionnaire can be improved further, e.g., by adding other programs to the list.

Aged↗