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Shinji Tamaki

Publications and source records attributed to Shinji Tamaki.

At least 19 recordsLinked to original sources
PubMed2006

Alcohol consumption and coronary artery calcium in middle-aged Japanese men.

Epidemiologic studies have investigated the relation between alcohol intake and coronary calcification, with controversial results. Furthermore, the influence of heavy drinking has not been well elucidated. In the present study, a random sample of community-based Japanese men aged 40 to 49 years without a history of cardiovascular disease (n=245) were examined for coronary artery calcium (CAC) determined by electron-beam computed tomography and drinking status. There was a J-shaped association between alcohol intake and CAC. There was an increase of CAC in heavy drinkers (>or=46 g/day), and participants who were drinking>or=69 g/day showed a significant increase in CAC compared with never drinkers after adjusting for other cardiovascular risk factors.

Adult↗
PubMed2006

The association between high-density lipoprotein cholesterol level and cholesteryl ester transfer protein TaqIB gene polymorphism is influenced by alcohol drinking in a population-based sample.

Cholesteryl ester transfer protein (CETP) is a key enzyme in high-density lipoprotein (HDL) cholesterol metabolism. We studied the association between CETP TaqIB polymorphism and the HDL cholesterol levels considering environmental factors in a population-based sample consisting of 1729 participants who did not use lipid-lowering agents (659 men and 1070 women). The CETP TaqIB genotypes were determined by PCR-RFLP analysis. The serum HDL cholesterol levels of female participants with the B2B2 genotype were significantly higher than those with other genotypes (p<0.001). Multiple regression analysis with covariates such as age, waist to hip (W/H) ratio, alcohol drinking, current smoking, non-HDL cholesterol, and logarithm of triglyceride revealed that the CETP TaqIB genotype was an independent determinant of HDL cholesterol levels in men (p=0.049) and women (p<0.001). Subgroup analysis revealed that an interaction was observed between the CETP TaqIB polymorphism and alcohol consumption in the regulation of HDL cholesterol levels in men (p=0.049) and women (p=0.022). No interactions were observed between the CETP TaqIB polymorphism and current smoking status, body mass index, or W/H ratio in the regulation of HDL cholesterol levels. The association between the CETP TaqIB polymorphism and HDL cholesterol levels was more evident in alcohol consumers than in non-drinkers.

Adult↗
PubMed2006

Evidence for activation of nuclear factor kappaB in obstructive sleep apnea.

Obstructive sleep apnea (OSA) is a risk factor for atherosclerosis, and atherosclerosis evolves from activation of the inflammatory cascade. We propose that activation of the nuclear factor kappaB (NF-kappaB), a key transcription factor in the inflammatory cascade, occurs in OSA. Nine age-matched, nonsmoking, and non-hypertensive men with OSA symptoms and seven similar healthy subjects were recruited for standard polysomnography followed by the collection of blood samples for monocyte nuclear p65 concentrations (OSA and healthy groups). In the OSA group, p65 and of monocyte production of tumor necrosis factor alpha (TNF-alpha) were measured at the same time and after the next night of continuous positive airway pressure (CPAP). p65 Concentrations in the OSA group were significantly higher than in the control group [median, 0.037 ng/microl (interquartile range, 0.034 to 0.051) vs 0.019 ng/microl (interquartile range, 0.013 to 0.032); p = 0.008], and in the OSA group were significantly correlated with apnea-hypopnea index and time spent below an oxygen saturation of 90% (r = 0.77 and 0.88, respectively) after adjustment for age and BMI. One night of CPAP resulted in a reduction in p65 [to 0.020 ng/mul (interquartile range, 0.010 to 0.036), p = 0.04] and levels of TNF-alpha production in cultured monocytes [16.26 (interquartile range, 7.75 to 24.85) to 7.59 ng/ml (interquartile range, 5.19 to 12.95), p = 0.01]. NF-kappaB activation occurs with sleep-disordered breathing. Such activation of NF-kappaB may contribute to the pathogenesis of atherosclerosis in OSA patients.

Adult↗
PubMed2006

Gender and age effects on ventricular repolarization abnormality in Japanese general carriers of a G643S common single nucleotide polymorphism for the KCNQ1 gene.

BACKGROUND: The KCNQ1 single nucleotide polymorphism (SNP), G643S, is known to be associated with secondary long QT syndrome (LQTS) and to cause a mild reduction in KCNQ1 current. However, the precise incidence and its association with QT intervals remain unknown in the greater cohort of the population in Japan. METHODS AND RESULTS: The genotype was screened at codon 643 of KCNQ1 in 992 residents of a farming community. Eighty-eight individuals (female/male =52/36, 8.9%) were found to have a heterozygous G643S SNP. Matching both gender and age, we randomly selected 243 control (G643G) cases and compared the electrocardiogram parameters in both groups; QT, QTf (QT corrected by Fridericia's formula) intervals, the peak and the end of the T wave (Tpe) interval, and the Tpe/QT ratio. The latter 2 reflect the transmural dispersion of ventricular repolarization (TDR). In G643S carriers, both Tpe and Tpe/QT were significantly longer than in non-carriers, without significant QT prolongation. Both genders showed a tendency for an increase in QTf with aging. In females, both Tpe and Tpe/QT showed a similar significant increase with age, which was not observed in males. CONCLUSIONS: In elderly females, G643S might be an independent risk factor for secondary LQTS by causing a greater TDR.

Adult↗
PubMed2006

Impact of paraoxonase polymorphism (Q192R) on endothelial function in intact coronary circulation.

Paraoxonase-1 (PON1) can protect endothelial function by preventing the oxidation of low-density lipoprotein (LDL) cholesterol and retarding the development of atherosclerosis. We examined whether PON1 polymorphism influences endothelium-dependent coronary vasomotor responses. Sixty-seven patients underwent diagnostic cardiac catheterization, but showed no significant coronary artery stenosis. In all patients, PON1 genotypes (Q/Q, Q/R and R/R) were determined, and provocative testing was performed by the intracoronary administration of graded doses of bradykinin (BK; 0.2, 0.6 and 2.0 mug/min) and acetylcholine (ACh; 3, 10 and 30 mug/min). Coronary blood flow (CBF) was evaluated by a Doppler guide wire. The patients were divided into 2 groups on the basis of ACh testing: one with coronary spastic angina (CSA) and one with non-CSA. The frequencies of the PON1 genotype in the CSA group did not differ significantly from those in the non-CSA group. In the non-CSA group, the patients were subdivided into 2 groups: a group with the Q/Q or Q/R genotypes and a group with the R/R genotype. The vasoconstrictive responses of the epicardial coronary artery to ACh were comparable between the Q/Q + Q/R and R/R groups. Also, the coronary vasodilations induced by BK in the R/R group were similar to those in the QR + QQ group. There were no significant differences in the CBF responses induced by BK or ACh between the Q/Q + Q/R and R/R groups. In conclusion, as estimated by BK and ACh testing, our findings suggest that PON1 genotypes may not play a critical role in the modulation of endothelial vasomotor function in the intact coronary circulation.

Acetylcholine↗
PubMed2005

Association between fish consumption and all-cause and cause-specific mortality in Japan: NIPPON DATA80, 1980-99.

PURPOSE: Although high consumption of fish may be one of the contributing factors for Japanese longevity, no epidemiological study using Japanese data has tested this hypothesis. SUBJECTS AND METHODS: The relationship between fish consumption and all-cause as well as cause-specific mortality was analyzed using the database of NIPPON DATA80. At baseline in 1980, history, physical, and blood biochemical measurement and a nutritional survey by the food-frequency method were performed in randomly selected community-based subjects aged 30 years and over in Japan. After exclusion of subjects with significant comorbidities at baseline, we followed 3945 men and 4934 women for 19 years. Men and women were analyzed comprehensively. Age- and sex-adjusted and multivariate adjusted relative risk for all-cause or cause-specific mortality was calculated using a Cox proportional hazards model with delayed entry. RESULTS: During 19 years of followup, there were 1745 deaths. Subjects were divided into 5 groups according to fish consumption frequency. The multivariate Cox analyses showed that relative risks for subjects who ate fish more than twice daily compared with those of subjects who ate 1 to 2 times weekly were 0.99 (95% confidence intervals: 0.77-1.27) for all-cause, 1.26 (0.70-2.29) for stroke, 0.92 (0.20-4.23) for cerebral hemorrhage, 1.09 (0.48-2.43) for cerebral infarction, and 0.91 (0.35-2.35) for coronary heart disease mortality. CONCLUSION: Our results did not provide evidence in support of the fish hypothesis, perhaps because the majority of the Japanese subjects in the study ate fish more than the threshold level shown to be beneficial in the previous studies.

Adult↗
PubMed2005

Combined analysis of polymorphisms in angiotensinogen and adducin genes and their effects on hypertension in a Japanese sample: The Shigaraki Study.

We examined the interactions between lifestyle and polymorphisms of salt-sensitive genes and their effects on hypertension in a general Japanese sample (The Shigaraki Study). The study group consisted of 2,902 subjects who underwent a medical examination in 1999 in Shigaraki, a suburban area in Shiga. Among 1,647 subjects not receiving antihypertensive medication, in a combined analysis of angiotensinogen (AGT) and adducin (ADD1) polymorphisms, double homozygosity of 235Thr or 460Trp was not found to be associated with hypertension. A multiple logistic regression analysis showed that age (odds ratio [OR]: 1.07, 95% confidence interval [95% CI]: 1.06-1.08), body mass index (BMI) (OR: 1.18, 95% CI: 1.13-1.23), alcohol consumption (OR: 1.39, 95% CI: 1.16-1.66), family history of hypertension (OR: 1.57, 95% CI: 1.18-2.07), and combined AGT M235T Thr/Thr and ADD1 Trp/Trp polymorphisms (OR: 1.37, 95% CI: 1.03-1.82) were associated with hypertension. However, there was no interaction between eating salty food and combined AGT and ADD1 polymorphisms. Furthermore, eating salty food was not associated with hypertension in a multivariate analysis. Therefore, a combination of the AGT and ADD1 polymorphisms appears to be associated with hypertension. However, a simple questionnaire regarding salt intake was not sufficient to confirm the relationship between salt intake and hypertension and/or salt-sensitive genes.

Adult↗
PubMed2005

[A familial case of summer-type hypersensitivity pneumonitis possibly associated with bird breeder's lung diagnosed by bronchoalveolar lavage fluid].

Case 1: A 32-year-old woman had cough and exertional dyspnea in August 2002, and chest computed tomographic scan revealed diffuse centrilobular nodules. Bronchoalveolar lavage fluid (BALF) showed a high proportion of lymphocytes with a decreased CD 4/CD 8 ratio. Transbronchial lung biopsy (TBLB) specimens showed alveolitis. Summer-type hypersensitivity pneumonitis was diagnosed on the basis of positive findings of anti-Trichosporon antibodies in the serum. Case 2: A 64-year-old man, the father of Case 1, also had cough and exertional dyspnea in August 2003. He had been in close contact with pigeons. Chest computed tomographic scan revealed bilateral map-like ground-glass opacities predominantly in the upper lobes. BALF showed a high proportion of lymphocytes with a decreased CD 4/CD 8 ratio. TBLB specimens showed alveolitis, granuloma and Masson body in the air spaces. Specific IgG and IgA antibodies against Trichosporon asahii, IgA antibodies against Trichosporon mucoides, and IgA antibodies against pigeon dropping extracts were found only in the BALF but not in the serum. Although a positive finding of returning-home provocation test was definitive in diagnosing summer-type hypersensitivity pneumonitis, he was also suspected of having bird fancier's lung.

Adult↗
PubMed2004

Much lower prevalence of coronary calcium detected by electron-beam computed tomography among men aged 40-49 in Japan than in the US, despite a less favorable profile of major risk factors.

BACKGROUND: Since World War II (WWII), exposures to westernized lifestyle have occurred in many non-Western countries, including Japan. National surveys showed that risk factor profiles for atherosclerosis around 1990 were similar in men in the post WWII birth cohorts in the US and Japan. We compared the degree of coronary calcium and other factors in men in the post WWII birth cohort: men aged 40-49 in the US and Japan. METHODS: We conducted a cross-sectional study examining randomly selected 100 men from Kusatsu, Japan, and 100 men from Allegheny County, US. Coronary calcium was assessed using electron-beam computed tomography. RESULTS: Systolic blood pressure, total cholesterol, low density lipoprotein (LDL)-cholesterol, and smoking rates were higher among the Japanese (122.6 +/- 14.1 versus 113.7 +/- 9.6 mmHg, P < 0.01; 5.72 +/- 0.90 versus 4.99 +/- 0.81 mmol/l (220.9 +/- 34.6 versus 192.8 +/- 31.3 mg/dl), P < 0.01; 3.52 +/- 1.01 versus 3.10 +/- 0.78 mmol/l (136.0 +/- 39.0 versus 119.7 +/- 30.0 mg/dl), P < 0.01; and 48 versus 15%, P < 0.01, respectively). Triglycerides and fibrinogen were similar. High density lipoprotein (HDL)-cholesterol was higher among the Japanese. Body mass index, fasting insulin, and C-reactive protein were higher among the Americans. Prevalence of coronary artery calcium score >0 was strikingly lower among the Japanese than the Americans (13% versus 47%, P < 0.01). CONCLUSIONS: Much lower prevalence of coronary calcium despite a less favourable profile of many major independent risk factors in the Japanese might imply that there are strong protective factors against atherosclerosis in the Japanese. Further investigation is of critical importance.

Adult↗
PubMed2004

Egg consumption, serum cholesterol, and cause-specific and all-cause mortality: the National Integrated Project for Prospective Observation of Non-communicable Disease and Its Trends in the Aged, 1980 (NIPPON DATA80).

BACKGROUND: Because egg yolk has a high cholesterol concentration, limited egg consumption is often suggested to help prevent ischemic heart disease (IHD). OBJECTIVE: We epidemiologically examined the validity of this recommendation. DESIGN: We analyzed the relations of egg consumption to serum cholesterol and cause-specific and all-cause mortality by using the NIPPON DATA80 (National Integrated Project for Prospective Observation of Non-communicable Disease And its Trends in the Aged, 1980) database. At the baseline examination in 1980, a nutritional survey was performed by using the food-frequency method in Japanese subjects aged > or =30 y. We followed 5186 women and 4077 men for 14 y. RESULTS: The subjects were categorized into 5 egg consumption groups on the basis of their responses to a questionnaire (> or =2/d, 1/d, 1/2 d, 1-2/wk, and seldom). There were 69, 1396, 1667, 1742, and 315 women in each of the 5 groups, respectively. Age-adjusted total cholesterol (5.21, 5.04, 4.95, 4.91, and 4.92 mmol/L in the 5 egg consumption categories, respectively) was related to egg consumption (P < 0.0001, analysis of covariance). In women, unadjusted IHD mortality and all-cause mortality differed significantly between the groups [IHD mortality: 1.1, 0.5, 0.4, 0.5, and 2.0 per 1000 person-years, respectively (P = 0.008, chi-square test); all-cause mortality: 14.8, 8.0, 7.5, 7.5, and 14.5 per 1000 person-years, respectively (P < 0.0001, chi-square test)]. In men, egg consumption was not related to age-adjusted total cholesterol. Cox analysis found that, in women, all-cause mortality in the 1-2-eggs/wk group was significantly lower than that in the 1-egg/d group, whereas no such relations were noted in men. CONCLUSION: Limiting egg consumption may have some health benefits, at least in women in geographic areas where egg consumption makes a relatively large contribution to total dietary cholesterol intake.

Adult↗
PubMed2004

Angiotensin converting enzyme genotype influences the response to the angiotensin II receptor antagonist losartan in patients with hypertension.

To examine whether the response to the angiotensin II receptor antagonist losartan varies depending on the angiotensin converting enzyme (ACE) genotype, we prospectively studied the effect of losartan in 42 hypertensive patients (20 men, 22 women; mean age: 60.4 years). After a 4-week observation period, losartan was administered at 50 mg/day and blood pressure was measured every 2 to 4 weeks for 12 weeks. Among the 42 patients, 19, 11, and 12, respectively, had the II, ID, and DD ACE genotypes. The baseline plasma ACE activity in patients with the ID or DD genotype was significantly higher than that in patients with the II genotype (13.8 +/- 4.2 vs. 9.6 +/- 2.3 IU/l; p = 0.0002). However, age, gender, baseline systolic and diastolic blood pressure (SBP/DBP), and body mass index (BMI) were not different among the groups. After 12 weeks of treatment with losartan alone, DBP in the ID+DD group was significantly higher than that in the II group (85.0 +/- 9.0 vs. 77.8 +/- 9.6 mmHg, p = 0.018), while the percent reduction in DBP in the ID+DD group was significantly smaller than that in the II group (7.9 +/- 8.8 vs. 14.3 +/- 10.1%, p = 0.035). Multiple regression analysis showed that the significant predictors of the DBP at 12 weeks were age (p = 0.030), ACE genotype (p = 0.029) and baseline DBP (p = 0.0001). The ACE genotype may be a determinant of the response to losartan in hypertensive patients.

Aged↗
PubMed2004

Angiotensin-converting enzyme insertion/deletion polymorphism modulates coronary release of tissue plasminogen activator in response to bradykinin.

The aim of this study was to assess the relationship between the angiotensin converting enzyme gene (ACE) genotype and endothelium-dependent coronary vasomotor and fibrinolytic activity. The ACE DD genotype has been reported to be a risk factor for myocardial infarction. However, the mechanism is unknown. The fibrinolytic and renin-angiotensin systems are linked via ACE at the vascular beds. We studied 73 patients (II: n=24; ID: n=37; DD: n=12) who underwent diagnostic cardiac catheterization. Graded doses of bradykinin (BK) (0.2, 0.6, 2.0 microg/min) and acetylcholine (30,100 microg/min) were administered into the left coronary artery. Coronary blood flow (CBF) was evaluated by measuring Doppler flow velocity. Blood samples were taken from the aorta (Ao) and the coronary sinus (CS). Coronary release of tPA antigen was determined as a CS-Ao gradientXCBFX[(100-hematocrit) / 100]. ACE genotypes were determined using polymerase chain reaction. The ACE genotype did not appear to affect coronary macro- and microvascular responses induced by BK or acetylcholine. Coronary tissue plasminogen activator (tPA) release induced by BK was depressed in subjects with the ACE DD genotype. ACE levels in the DD genotype were significantly higher than those in the ID or II genotype. In all of the subjects, there was a significant negative correlation between the serum level of ACE activity and net coronary tPA release in response to BK at 0.6 microg/min. In conclusions, the DD genotype of the ACE gene impairs the coronary release of tPA induced by BK.

Aged↗
PubMed2003

[Effect of lung volume reduction surgery (LVRS) on nutritional status in patients with COPD].

The beneficial effects of lung volume reduction surgery (LVRS) on patients with severe chronic obstructive pulmonary disease (COPD) on pulmonary function and exercise performance has been established. However, the impact on nutritional status and prognosis has not been demonstrated. In the present study, we investigated the changes in nutritional status in COPD patients undergoing bilateral thoracoscopic LVRS and also analyzed the relationship between nutritional status and postoperative complications and prognosis. After LVRS, body weight, fat-free mass (FFM) and caloric intake were significantly increased. Increase in FFM correlated significantly with improvement in exercise performance. In underweight patients before LVRS, the incidence of post-operative complications was significantly higher than in normal-weight patients, and a patient who was moderately-to-severely underweight (% ideal body weight < 80%) had a significantly poor prognosis. These findings suggest that improvement of nutritional status after LVRS contributes to improvement in exercise performance, and that preoperative nutritional status has a significant impact on postoperative morbidity and mortality. From our data, we concluded that preoperative nutritional assessment is an important part of the preoperative evaluation of LVRS, and that LVRS provides nutritional benefits for underweight patients with severe COPD.

Aged↗
PubMed2002

Genetic variation in aldehyde dehydrogenase 2 and the effect of alcohol consumption on cholesterol levels.

UNLABELLED: Moderate drinkers with a defective alcohol dehydrogenase type 3 (ADH3) genotype have higher high-density lipoprotein (HDL) levels and a decreased risk of coronary artery disease (CAD). We examined the interaction between the aldehyde dehydrogenase type 2 (ALDH2), alcohol intake, and HDL levels in 826 men and 1295 women in a rural town in Japan. The ALDH2 genotype of each subject was determined by polymerase chain reaction (PCR) analysis. HDL was adjusted for the alcohol intake, age, body mass index, smoking status, total cholesterol, triglycerides and HbA1c levels. None of the subjects had a history or ECG suggestive of CAD. The proportions of ALDH2, *1/*1, *1/*2, and *2/*2 (defective homozygote) were 45.8, 46.0, and 8.2%, respectively, for men. Drinking more than two drinks daily was associated with lower HDL levels in men with the defective genotypes compared with men with a normal genotype (55.6+/-0.9 vs. 51.2+/-0.9 mg/dl, mean+/-S.E., P<0.0001). Also, drinking more than 0.5 drinks daily was not associated with beneficial effects on HDL levels in women with defective ALDH2 genotypes. CONCLUSIONS: Alcohol intake did not have beneficial effects on HDL levels in the defective ALDH2 genotype and may not protect against CAD in subjects with defective ALDH2 genotypes.

Adult↗
PubMed2002

Polymorphism of the angiotensin converting enzyme gene and blood pressure in a Japanese general population (the Shigaraki Study).

Recent studies have described a linkage between angiotensin converting enzyme (ACE) gene polymorphism and hypertension in a large number of hypertensive sibs. Moreover, among Japanese, the DD genotype of the ACE gene has been reported to be a genetically predisposing factor for hypertension in a large general population. However, there is some controversy regarding the association between the ACE insertion/deletion (I/D) polymorphism and systemic hypertension. Therefore, we examined the influence of the ACE I/D polymorphism in a random Japanese population. The participants were 2,892 subjects (1,110 males: mean age, 58.4 +/- 15.5; 1,782 females: mean age, 56.2 +/- 15.7) who underwent medical examinations in 1999 in Shigaraki, a suburban town located in an urban area in Shiga prefecture. Among them, 2,395 subjects (917 males: mean age, 58.0 +/- 15.7; 1478 females: mean age, 56.3 +/- 15.6) who gave their informed consent for genetic analysis were enrolled in the present study. Every year since 1991, we have repeatedly performed medical examinations in Shigaraki. ACE genotypes were determined by polymerase chain reaction (PCR) methods. Logistic analysis revealed that age (p < 0.001; odds ratio = 1.091), body mass index (BMI) (p < 0.001; odds ratio = 1.211), and family history of hypertension (p < 0.001; odds ratio = 0.371) were associated with hypertension (systolic blood pressure greater than 140 mmHg and diastolic greater than 90 mmHg). There was no association between ACE polymorphism and blood pressure. There were also no significant differences in blood pressure among males or females across the three genotypes. Moreover, in an analysis of 1,484 subjects (549 males: mean age, 62.8 +/- 12.1; 935 females: mean age, 61.2 +/- 12.6) who were followed-up since 1991, there was no association between ACE polymorphism and changes in blood pressure (p = 0.3905). We conclude that ACE polymorphism does not appear to have any significant association with blood pressure, changes in blood pressure or sex in Japanese subjects, who have a more homogeneous genetic background than any other group reported to date.

Adult↗