Biomedical subjects

Isao Kato

Publications and source records attributed to Isao Kato.

At least 19 recordsLinked to original sources

PubMed2006

Angiotensin I-converting enzyme gene polymorphism modifies the smoking-cancer association: the Hisayama Study.

We examined the long-term contribution of smoking and angiotensin I-converting enzyme (ACE) gene I/D polymorphism to total cancer deaths in a prospective study of a general Japanese population. A total of 937 subjects aged 40 years or older were selected from an original cohort of 1621 subjects and were followed up for 32 years. During the follow-up period, 176 subjects died of cancer. Cancer mortality increased significantly with increasing current smoking levels. Although no clear relationship was observed between ACE genotypes and fatal cancer, the interaction term between current smoking and ACE genotype DD was found to be significant. In stratified analysis by ACE genotype after controlling for age, sex, alcohol intake, body mass index, glucose intolerance, serum total cholesterol and systolic blood pressure, the risk of fatal cancer in currently smoking subjects with genotype DD was twofold greater than that in subjects with genotypes II and ID. Among current smokers, subjects with genotype DD also showed a significantly greater risk of death due to cancer compared with those with genotypes II and ID combined (hazard ratio 1.77; 95% confidence interval 1.04-3.00; P=0.03). In conclusion, our findings suggest that ACE genotype DD enhances the association between smoking and cancer death in the general population.

Aged↗

PubMed2006

The influence of current and former smoking on gingival bleeding: the Hisayama study.

BACKGROUND: Previous studies have shown that smoking is a risk factor for periodontitis and that it has a suppressive effect on gingival bleeding. This study examined the relationship between smoking, including past smoking, and periodontal conditions, mainly gingival bleeding, in a community-based health investigation. METHODS: Smoking status was examined in 958 subjects, along with the quantity of tobacco currently or previously smoked (never, former light, former heavy, current light, and current heavy). We analyzed the influence of smoking on probing depth (PD), clinical attachment loss (CAL), and gingival bleeding on probing (BOP). RESULTS: In multivariate logistic regression analyses, current heavy smokers were at a significantly greater risk for having a higher proportion of teeth with PD > or =4 mm and a higher proportion of teeth with CAL > or =5 mm; however, they had a lower risk for having a high BOP than did those who had never smoked. Moreover, both former light and former heavy smokers had significantly lower risks for high BOP. When the analysis was limited to subjects with PD > or =4 mm, former heavy and current heavy smokers showed a significant suppression of high BOP compared to never smokers. CONCLUSION: This study suggests that smoking is significantly associated with PD and CAL and that current and past smoking has a suppressive effect on BOP.

Adult↗

PubMed2005

Relationship between drinking and periodontitis: the Hisayama Study.

BACKGROUND: Although recent studies suggest a relationship between alcohol consumption and periodontal disease, the dose-response relationship between drinking and the severity of periodontitis is unclear. METHODS: Alcohol consumption was evaluated using the frequency of drinking and the daily alcohol intake for 961 individuals aged 40 to 79 years. Periodontal status was evaluated using probing depth (PD) and clinical attachment loss (CAL). RESULTS: Alcohol consumption was linearly associated with the extent of PD and CAL in univariate analyses (P <0.001). In multivariate logistic regression analyses, the subjects drinking 15 to 29.9 g alcohol per day (odds ratio [OR] = 2.7; 95% confidence interval [CI] = 1.1 to 6.6) or more than 30 g per day (OR = 2.5; 95% CI = 1.1 to 5.7) had a significantly higher risk of having more than 35% of their teeth with PD > or = 4 mm than non-drinkers, independent of other confounding variables. No significant relationship between drinking and CAL was observed in the multivariate analysis. CONCLUSION: These results suggest that the effect of drinking on periodontal condition is limited to subjects with deep periodontal pockets associated with more than one-third of their teeth.

Adult↗

PubMed2005

Impact of fasting plasma glucose levels on gastric cancer incidence in a general Japanese population: the Hisayama study.

OBJECTIVE: Several studies have shown associations between diabetes and various types of cancer other than gastric cancer. The aim of this cohort study was to evaluate the impact of fasting plasma glucose (FPG) levels on gastric cancer occurrence. RESEARCH DESIGN AND METHODS: A total of 2,466 Japanese subjects aged > or =40 years were stratified into three groups according to FPG tertiles (<5.3 mmol/l, low FPG; 5.3-5.8 mmol/l, modest FPG; >5.8 mmol/l, high FPG) and followed up prospectively for 9 years. RESULTS: During the follow-up, 66 subjects experienced gastric cancer. In men, the age-adjusted incidences were significantly higher in the modest-FPG (7.0 per 1,000 person-years, P < 0.05) and high-FPG (7.2, P < 0.05) groups than in the low-FPG group (2.2). In women, the high-FPG group also had a significantly higher age-adjusted incidence of gastric cancer compared with the low-FPG group (2.5 vs. 0.8, P < 0.05). The multivariate analysis with Cox's proportional hazards model revealed that the risks of gastric cancer in the modest-FPG (relative risk [RR] 2.3 [95% CI 1.1-5.0]) and high-FPG (3.1 [1.5-6.4]) groups were significantly higher than that in the low-FPG group, even after adjusting for other comprehensive risk factors, including Helicobacter pylori status, smoking, and dietary factors. However, this FPG-cancer association was observed only among H. pylori-seropositive subjects. CONCLUSIONS: Our findings suggest that a modest increase in FPG is a risk factor for gastric cancer and that hyperglycemia is a possible cofactor increasing the risk posed by Helicobacter pylori infection.

Adult↗

PubMed2004

Relationship between plasma glutathione levels and cardiovascular disease in a defined population: the Hisayama study.

BACKGROUND AND PURPOSE: Glutathione (GSH) appears to have marked antioxidant activities and therefore may prevent cardiovascular disease (CVD). However, there are very few reports on this subject. In a community-based case-control study, we tested the hypothesis that low levels of plasma GSH are closely associated with CVD and its clinical types. METHODS: The association between fasting plasma total GSH (tGSH) levels and CVD were assessed using conditional logistic regression analysis among 134 CVD cases and 435 age- and sex-matched healthy control subjects. RESULTS: Mean tGSH concentrations were lower in all CVD cases than in the control subjects (3.06 versus 3.71 micromol/L; P=0.0001). Among the CVD types, both the cerebral infarction cases (2.98 versus 3.59 micromol/L; P=0.001) and cerebral hemorrhage cases (2.51 versus 3.43 micromol/L; P=0.0027) had significantly lower tGSH levels than the corresponding control groups had. The same tendency was observed for cases of subarachnoid hemorrhage (3.45 versus 3.83 micromol/L; P=0.36) and myocardial infarction (3.65 versus 3.77 micromol/L; P=0.69), but these differences were not statistically significant. After adjustment for other confounding factors, the risk of CVD was significantly lower in the third (adjusted odds ratio, 041; 95% CI, 0.21 to 0.77) and the fourth quartiles (adjusted odds ratio, 0.25; 95% CI, 0.12 to 0.51) than in the first. This association was most prominent in patients with lacunar infarction or cerebral hemorrhage. CONCLUSIONS: These findings suggest that reduced plasma tGSH levels are a risk factor for CVD, especially for cerebral small vessel disease.

Aged↗

PubMed2004

Relationship between electrocardiographic abnormalities and periodontal disease: the Hisayama Study.

BACKGROUND: Recent studies have suggested a relationship between periodontitis and cardiovascular disease (CVD). This study investigated the relationship between periodontitis and electrocardiographic (ECG) abnormalities, which are known predictors of CVD. METHODS: We examined the periodontal status of 1,111 residents of Hisayama Town, Fukuoka, Japan. Nine hundred fifty-seven (957) subjects (374 males, 583 females) with > or = 10 teeth and without a medical history of CVD were included in the analysis. Probing depth (PD) and clinical attachment level (CAL) were measured on two randomly selected quadrants, one maxillary and one mandibular. A 12-lead ECG was recorded using a standard electrocardiograph. ECG abnormalities included left ventricular hypertrophy (Minnesota code 3-1) and ST depression (4-1, 2, 3). The relation of periodontal condition and ECG abnormalities was assessed with logistic regression analysis. RESULTS: Univariate analysis revealed that mean probing depth, mean attachment loss, number of teeth, and plaque index were significantly associated with ECG abnormalities, as well as with known risk factors of CVD. In multivariate analysis, the subjects with deep pockets (mean probing depth > or = 2 mm) had an increased risk for ECG abnormalities (odds ratio [OR] = 1.6; 95% confidence interval [CI] = 1.01 to 2.50) compared to the subjects with mean PD < 2 mm. Subjects with severe attachment loss (mean CAL > or = 2.5 mm) had also significant risk for ECG abnormalities (OR = 1.7; 95% CI = 1.07 to 2.67) compared to those whose mean CAL was < 2.5 mm. CONCLUSION: This study clearly shows the relationship between periodontitis and ECG abnormalities, which are important predictors of CVD.

Adult↗

PubMed2004

Hyperhomocysteinemia and the development of chronic kidney disease in a general population: the Hisayama study.

BACKGROUND: Hyperhomocysteinemia has been linked with various atherosclerotic diseases, but has not been evaluated sufficiently as a risk factor for the development of chronic kidney disease (CKD) in the general population. METHODS: To clarify this issue, we followed up 1,477 community-dwelling individuals without CKD, aged 40 years or older, for 5 years and examined the effects of baseline serum total homocysteine (tHcy) levels on the development of CKD. RESULTS: During follow-up, 88 subjects experienced CKD. Baseline tHcy levels were greater in men than women (1.35 versus 1.04 mg/L [10.0 versus 7.7 micromol/L]; P < 0.01). Age-adjusted 5-year incidences were 2.2% in the low tertile, 5.4% in the middle tertile, and 8.6% in the high tertile of tHcy levels for men and 3.3%, 6.0%, and 6.9% for women, respectively. The difference between the low and high tertiles was statistically significant for both sexes ( P < 0.05). In multivariate analysis, these relationships remained substantially unchanged, even after adjustment for other confounding factors, such as systolic blood pressure, antihypertensive medication, hemoglobin A 1c level, total cholesterol level, high-density lipoprotein cholesterol level, habitual smoker status, regular alcohol intake, proteinuria, and baseline kidney function (odds ratio [OR] in the high tertile of tHcy levels, 2.09; 95% confidence interval [CI], 0.66 to 6.61 for men; OR, 2.86; 95% CI, 1.10 to 7.43 for women). Furthermore, baseline tHcy level showed a significantly inverse association with rate of change in kidney function during the 5 years after being adjusted for confounding factors, including baseline kidney function. CONCLUSION: Our findings suggest that elevated serum tHcy levels are a significant risk factor for the development of CKD in the general population.

Aged↗

PubMed2003

Ten-year prognosis of stroke and risk factors for death in a Japanese community: the Hisayama study.

BACKGROUND AND PURPOSE: There have been very few population-based cohort studies of long-term prognosis and risk factors for death after stroke. We examined the 10-year prognosis, causes, and risk factors of death after stroke in a Japanese cohort. METHODS: During a 26-year follow-up of a cohort of 1621 subjects > or =40 years of age, 333 subjects developed first-ever stroke and were prospectively followed up for 10 years after onset. During these 10-year follow-up periods, 268 of the 333 stroke patients died. Of those, 239 (89.2%) underwent autopsy. RESULTS: The risk of death was greatest in the first year after first-stroke onset in both sexes (men, 40.3%; women, 43.7%). Thereafter, the survival curves decreased gradually, and risk of death reached 80.7% for men and 80.2% for women by the end of the 10-year follow-up. The 30-day case fatality rate was substantially greater in patients with cerebral hemorrhage (63.3%) or subarachnoid hemorrhage (58.6%) than in patients with cerebral infarction (9.0%). The risk of dying after the first stroke was twice the risk for stroke-free subjects. The most common cause of death was the index stroke in the first year. Thereafter, the impact of the first stroke gradually decreased, while that of recurrent stroke increased. Multivariate analysis revealed that age, lower body mass index, and hemorrhagic stroke were significant risk factors for death after stroke. CONCLUSIONS: Our findings suggest that the risk of death after first-ever stroke is high, in part because of the larger proportion of hemorrhagic stroke in Japanese relative to stroke victims in Western countries.

Age of Onset↗

PubMed2003

Trends in the incidence, mortality, and survival rate of cardiovascular disease in a Japanese community: the Hisayama study.

BACKGROUND AND PURPOSE: The slowdown of a steeply declining trend in cardiovascular mortality has been reported in Japan, but precise reasons for this trend are uncertain. METHODS: We established 3 study cohorts of Hisayama residents aged > or =40 years without a history of stroke or myocardial infarction in 1961 (1618 subjects, first cohort), 1974 (2038 subjects, second cohort), and 1988 (2637 subjects, third cohort). We followed up with each cohort for 12 years, comparing the incidence, mortality, and survival rate of cardiovascular disease. RESULTS: The age-adjusted incidence of cerebral infarction significantly declined by 37% for men and by 32% for women from the first to the second cohort. It continued to decline by 29% for men, but the decline decelerated for women in the third cohort. The incidence of cerebral hemorrhage steeply declined by 61% from the first to the second cohort in men only, while it was sustained for both sexes in the third cohort. Stroke mortality continuously declined as a result of these incidence changes and significant improvement of survival. In contrast, the incidence and mortality rate of coronary heart disease were unchanged except for the increasing incidence in the elderly. The prevalence of severe hypertension and current smoking significantly decreased, while that of glucose intolerance, hypercholesterolemia, and obesity greatly increased among the cohorts. CONCLUSIONS: Our data suggest that the decline in stroke incidence is slowing down and that the incidence of coronary heart disease has been increasing in the elderly in recent years. Insufficient control of hypertension and the increase in metabolic disorders may contribute to these trends.

Adult↗

PubMed2003

Validity of the JNC VI recommendations for the management of hypertension in a general population of Japanese elderly: the Hisayama study.

BACKGROUND: It is not known whether the treatment recommendations presented in the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure are applicable to the Japanese elderly population. METHODS: We followed up 588 cardiovascular disease-free residents of a Japanese community who were 60 years or older from November 1, 1961, through October 31, 1993. Treated hypertensive patients were excluded from the analysis. During this period, CVD occurred in 179 subjects. The incidences were estimated by the pooling of repeated observations method. RESULTS: The age- and sex-adjusted incidences of cardiovascular disease significantly increased with elevated blood pressure levels. The hazard ratio for stage 3 hypertension was 5.34 (95% confidence interval, 2.66-10.71; P<.001) compared with optimal blood pressure after adjustment for other covariates. Among subjects aged 60 to 79 years, the incidences for stages 1 through 3 hypertension were significantly higher than for those with optimal and normal blood pressure. In comparison, among those 80 years or older, the incidence was significantly higher only in patients with stage 3 hypertension. We further estimated the incidences according to the risk stratification system. In the younger elderly subjects, the incidences increased with rising blood pressure levels in each risk stratum. Similar relationships were not observed among the older elderly subjects. CONCLUSIONS: Our findings demonstrate that the recommendations of the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure were potentially applicable to the Japanese elderly subjects 79 years or younger. Based on our findings, however, hypertension might not be a risk factor for cardiovascular disease among very old hypertensive patients with advanced atherosclerosis.

Age Factors↗

PubMed2003

Wallenberg's syndrome: neurotological classification.

OBJECTIVES: Visually induced eye movements were investigated in 26 patients with Wallenberg's syndrome. METHODS: Slow-phase optokinetic nystagmus (OKN) velocities, pursuit gains, and percentage fixation suppression (%FS) of caloric nystagmus were recorded by DC electrooculography (EOG), and stored directly onto FM magnetic tape. RESULTS: OKN velocities, pursuit gains, and %FS decreased toward the lesion side (group A), whereas OKN velocities and pursuit gains decreased toward the side contralateral to the lesion side. %FS decreased toward the lesion side (group B). MR images in group A showed that lesions were only in and near to the vestibular nuclei, and images in group B showed that lesions extended to the cerebellum. CONCLUSION: Visually guided eye movements allow classification of Wallenberg's syndrome into two types, one with brainstem lesions and one with both brainstem and cerebellar lesions. This demonstrates that assessing eye movements is helpful in supplementing MRI data.

Adult↗

PubMed2003

End-to-end anastomosis in chronic tracheal stenosis.

OBJECTIVE: This study assessed the efficacy and safety of end-to-end anastomosis of the trachea following segmental resection in chronic tracheal stenosis. METHODS: End-to-end anastomoses of the trachea were performed in 35 patients with chronic tracheal stenosis; 18 patients with tracheal invasion of thyroid cancer and 17 patients with long-term intubation and blunt injuries of the trachea. RESULTS: All operations were successful, except one whose unilateral recurrent nerve had not been identified in the recurrent thyroid cancer invasion with trachea. CONCLUSION: This operation provides a one-step cure for the stenosed trachea and can be applied to the resection of less than six tracheal segments.

Adenocarcinoma↗

PubMed2003

Horizontal eye response to an abrupt lateral head drop in normal subjects and patients with Meniere's disease.

OBJECTIVE: To detect the endolymphatic hydrops by using the otolithic nature in patients with Meniere's disease and delayed hydrops. METHODS: We developed a new technique for measuring horizontal eye movements, corresponding to lateral head drop in total darkness, approximately 1g environment. Normal subjects (n=16, mean age: 27.3 years old) and patients (seven for pre-operative state, four for furosemide test at pre-operative state; two for post-operative state) were employed in the test. The principle of the test is to drop the head in a lateral position separately from the body with a rapid release exposing the head. Bitemporal EOG, accelometric and trigger signals for the releaser were recorded for processing at 1 KHz sampling time. RESULTS: The drop was performed five times in succession. The latency of horizontal eye response was of 40 ms order in normal subjects on both sides and were never beyond 60 ms. Eye response of the patients was in different patterns from normal subjects and the latencies delayed either to normal side or to the affected side. Following furosemide intravenous injection, more certain information was obtained. Three of four patients were recovered to normal range as to the latency. CONCLUSIONS: We emphasize that this test may provide a new measure sensitive to the hydrops and can underline this test to detect the hydrops in Meniere's disease.

Adult↗

PubMed2003

Retrograde-labeling of pretecto-vestibular pathways in cats.

The projections of the nucleus of the optic tract (NOT) were studied in cats using three kinds of retrograde tracers (horseradish peroxidase wheat germ agglutinin (WGA-HRP), dextran fluorescein (DF) and dextran tetramethylrhodamine (DTR)). First, in the cases that WGA-HRP were injected into the rostral part of medial vestibular nucleus (VN), a significant number of retrograde-labeled neurons, which concentrated between 600 and 800 micrometer from the rostral part of the NOT, were observed in the NOT ipsilateral to the injection sites. Second, no double-labeled neurons were found following injections of DF in the medial VN and DTR in the nucleus prepositus hypoglossi (NPH) at the same time. In this experiment, it was made clear that two different kinds of neurons in the NOT projected to the medial VN and the NPH, respectively.

Animals↗

PubMed2003

Insulin-mediated effects of alcohol intake on serum lipid levels in a general population: the Hisayama Study.

To determine whether the beneficial effects of alcohol on lipid concentrations are mediated by insulin levels, we performed a cross-sectional analysis in 2103 nondiabetic men and women aged 40 to 79 years from a general Japanese population in Hisayama. The multivariate-adjusted sum of fasting and 2-hour postloading insulin levels and the insulin resistance index significantly decreased with elevating alcohol intake levels in men (P < 0.01 for the trend) but not in women. No dose-response relations between alcohol intake and glucose levels were observed. In both sexes, high-density lipoprotein cholesterol (HDLC) significantly increased with elevated alcohol intake (P < 0.01), whereas total cholesterol and low-density lipoprotein cholesterol (LDLC) were inversely correlated with alcohol intake (P < 0.01). In contrast, triglycerides (TGs) levels in men showed a J-shaped relation to alcohol dose, with moderate drinkers (10-29 g/d) having the lowest levels. Estimates using regression models indicated that for men, 10% of the alcohol-induced increase in HDLC and 2% of the alcohol-induced decrease in LDLC were insulin mediated. It was also estimated for male subjects that 36% of the reduction in TGs due to low to moderate alcohol intake was mediated by low levels of insulin and that this insulin-mediated pathway reduced the positive alcohol-TG relation by 13% in cases of moderate to heavy drinking. Our data suggest that regular alcohol consumption dose-dependently increased insulin sensitivity among male nondiabetics, but the insulin-mediated beneficial effects of alcohol on lipid concentrations were relatively small.

Adult↗

PubMed2003

Risk factors for renal glomerular and vascular changes in an autopsy-based population survey: the Hisayama study.

BACKGROUND: Information of the effect of cardiovascular risk factors on renal glomerular and vascular changes is scarce in the general population. METHOD: Between 1962 and 1994, 1394 autopsies were performed in Hisayama, for a total autopsy rate of 80%. Of these, 839 individuals who preserved adequate renal tissues and had recent health examinations data before death were eligible for the present study. We examined the degree of glomerular sclerosis, renal arteriolar hyalinosis, and arteriosclerosis, and evaluated their risk factors by means of a logistic regression model. RESULTS: The development of glomerular sclerosis, arteriolar hyalinosis, and arteriosclerosis were 16%, 16%, and 18% in men, respectively, and 27%, 15%, and 24% in women, respectively. All these frequencies increased linearly with advancing age. In the multivariate analysis, both age and systolic blood pressure were significant independent risk factors for almost all these glomerular and vascular changes. In addition, glucose intolerance and proteinuria for men were found to be significant risk factors for glomerular sclerosis. Elevated total cholesterol levels significantly increased the risk of arteriolar hyalinosis in men. Electrocardiogram (ECG) abnormalities were an independent risk factor for arteriosclerosis in both men and women, and proteinuria was an additional risk factor in women. Alcohol intake tended to have a protective effect on glomerular sclerosis and arteriosclerosis in women. CONCLUSION: Our data confirmed that age and systolic blood pressure are common risk factors for all glomerular and renal vascular changes in the general population. In addition, glucose intolerance, total cholesterol, ECG abnormalities, and proteinuria affect either glomerular or vascular changes.

Age Distribution↗

PubMed2003

Aerobic denitrifying bacteria that produce low levels of nitrous oxide.

Most denitrifiers produce nitrous oxide (N(2)O) instead of dinitrogen (N(2)) under aerobic conditions. We isolated and characterized novel aerobic denitrifiers that produce low levels of N(2)O under aerobic conditions. We monitored the denitrification activities of two of the isolates, strains TR2 and K50, in batch and continuous cultures. Both strains reduced nitrate (NO(3)(-)) to N(2) at rates of 0.9 and 0.03 micro mol min(-1) unit of optical density at 540 nm(-1) at dissolved oxygen (O(2)) (DO) concentrations of 39 and 38 micro mol liter(-1), respectively. At the same DO level, the typical denitrifier Pseudomonas stutzeri and the previously described aerobic denitrifier Paracoccus denitrificans did not produce N(2) but evolved more than 10-fold more N(2)O than strains TR2 and K50 evolved. The isolates denitrified NO(3)(-) with concomitant consumption of O(2). These results indicated that strains TR2 and K50 are aerobic denitrifiers. These two isolates were taxonomically placed in the beta subclass of the class Proteobacteria and were identified as P. stutzeri TR2 and Pseudomonas sp. strain K50. These strains should be useful for future investigations of the mechanisms of denitrifying bacteria that regulate N(2)O emission, the single-stage process for nitrogen removal, and microbial N(2)O emission into the ecosystem.

Aerobiosis↗

PubMed2003

Formal synthesis of squalamine from desmosterol.

The key intermediate to squalamine, (5alpha,7alpha,24R)-7,24-dihydroxy-cholestan-3-one, was synthesized from the 3-O-acetyl-24R,25-dihydroxy derivative of desmosterol via 10 steps in 16% overall yield and squalamine was also prepared via two further steps in 7.4% total yield from the desmosterol derivative.

Cholestanols↗