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Biomedical subjects

S Tsugane

Publications and source records attributed to S Tsugane.

At least 37 records · Page 2Linked to original sources

hOGG1 exon7 polymorphism and gastric cancer in case-control studies of Japanese Brazilians and non-Japanese Brazilians.

Polymorphism of hOGG1 may be capable of serving as a genetic marker for individual susceptibility to various cancers because of its role in the repair of oxyradical DNA damage. We examined the distribution of the hOGG1 Ser326Cys polymorphism and its presumed correlation with gastric cancer risk in two case-control studies of different ethnic groups in São Paulo, Brazil. Potentially eligible Japanese (JB) and non-Japanese Brazilian (NJB) case subjects were defined as patients with newly diagnosed malignant neoplasms of the stomach in 13 hospitals in São Paulo. Ninety-six JBs and 236 NJBs were adopted as subjects. Two controls were matched for each JB case, and one control for each NJB case. The subjects were interviewed using a questionnaire and their blood samples were collected. A significant difference in the distribution of this polymorphism between the two ethnic groups was observed (chi(2)=58.3, P<0.01). The mutant type (Ser/Cys or Cys/Cys) was predominant (approximately 65%) in the JBs, but was only present in approximately 40% of the NJBs. Logistic regression analysis showed no significant increased risk for either the Ser/Cys or Cys/Cys type in either group. The odds ratios of the Cys allele for gastric cancer were 1.01 (95% confidence interval (CI): 0.52-1.93) in the JBs and 0.85 (95% CI: 0.57-1.26) in the NJBs. In the NJBs, a significant increased risk of smoking was shown only in the Ser/Ser type, and no increased risk was shown in the genotypes with the Cys allele. However, no statistically significant interactions were observed with smoking or other possible confounding factors. No statistically significant difference in the distribution of the polymorphism was observed between the intestinal type and diffuse type of gastric cancer in either the JBs or the NJBs. The ethnic difference in hOGG1 Ser326Cys polymorphism was much greater than the case-control difference, and this polymorphism is unlikely to be associated with gastric cancer.

Aged↗

Genomic structure and loss of heterozygosity of EPHB2 in colorectal cancer.

EphB2, a member of the Eph receptor protein-tyrosine kinase family, is overexpressed in several human gastrointestinal tumors. Furthermore, the EphB2 gene is localized at 1p35-p36.1, a frequently deleted region in colon and other cancers. So, despite its overexpression in some kind of tumors, we decided to study the possibility of involvement in the EphB2 gene (EPHB2) mutation in colon cancers, because some of the well known tumor suppressor genes (e.g. p53) is overexpressed (really accumulated) in tumors. Fifty colon tumor samples of matched with their respective normal tissues, were studied for mutation of the EPHB2. Analysis of the genomic structure of EphB2 and survey of all 16 exons revealed an infrequent polymorphism (intron 2) and mutation (intron 8). Another polymorphism in exon 6, localized at nucleotide 1359 (A-->G) was found to be rather frequent in Japanese and Chinese subjects, but very rare in Caucasians. Taking advantage of this polymorphism within EPHB2, we surveyed the loss of heterozygosity (LOH) status of this gene in Japanese colorectal tumors. Among the 50 samples analyzed, 24 were informative, and LOH was found in five of the15 (33.3%) informative rectal cancer cases. Mutation analysis covering all 16 exons in the remaining allele did not reveal any mutations. Thus, EPHB2 is not a classical tumor suppressor gene.

Aged↗

Histopathological modifications of early atherosclerotic lesions by risk factors--findings in PDAY subjects.

To investigate whether histopathological modifications on early atherosclerotic lesions differ according to risk factors, we compared the histological findings of arteries obtained from a multicenter study in the USA (Pathobiological Determinants of Atherosclerosis in Youth, PDAY) with the antemortem risk factors. The materials comprised aortas and left anterior descending (LAD) coronary arteries of 140 male subjects. Measurements of intimal thickness, classification of intimal lesions, and density of foam cells and intimal fibrosis at the determined sites of LAD and aorta were evaluated. In both arteries, intimal thickness of hypertensives was greater than the normotensives with no definite proliferation of foam cells. In aortas, hypercholesterolemia was associated with an increase in foam cells, but not with an increase in intimal thickness. HDL-C value correlated inversely with number of foam cells in both the arteries, and the degree of intimal thickness in LADs, where early appearance of advanced lesion such as preatheroma and atheroma, was also indicated in the low HDL-C group. Smokers had less number of foam cells in both the arteries and more intensive intimal fibrosis in LAD than non-smokers. Our study suggests that there are several ways to advanced atherosclerotic lesions by risk factors.

Adolescent↗

Importance of standardization of hemoglobin A1c in the analysis of factors that predict hemoglobin A1c levels in non-diabetic residents of three distinct areas of Japan.

We performed a statistical analysis to elucidate effects of standardized measurement of hemoglobin A1c (HbA1c) on analysis of factors that affect HbA1c values. Subjects were participants in the Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases, and a total of 1789 men and 3150 women in three distinct areas who did not have overt diabetes (HbA1c> or =6.1% or prior diagnosis) were analyzed. A different method of HbA1c assay was used in each area: high-performance liquid chromatography in one area and a different immunochemical method in each of the other two areas. Then, calibration of HbA1c was performed using two HbA1c standards (5.5 and 10.5%) provided by the Japan Diabetes Society. Analysis of co-variance was performed separately in men and women. When raw HbA1c data were used as the outcome, 'area', which represents differences in assay systems, lifestyles, etc. had a significant effect on HbA1c levels. When calibrated HbA1c data were used, however, 'area' was no longer a significant factor. In the latter analysis, age and BMI were the principal contributors to HbA1c, and parental history of diabetes had a weak effect in women. Thus, standardization of HbA1c reduced the difference between assay systems, and uncovered two common factors to determine HbA1c levels.

Adult↗

Sensitivity of self-reports of cancer in a population-based prospective study: JPHC Study Cohort I.

The sensitivity of self-reports of cancer may differ among cultures, and not many studies have dealt with it. The authors measured the sensitivity of 615 individuals from the JPHC Study Cohort I in Japan who responded to a questionnaire in 1995 and had had a cancer registry report since 1990. Sensitivity as calculated using registered cancer as the gold standard was 0.36 for any cancer, but varied considerably by site: 0.81, 0.42, 0.41, 0.26, 0.14 and 0.08 for breast, uterus, stomach, lung, colorectum and liver, respectively. This sensitivity by site relates positively with the cancer incidence/death ratio (an index of prognosis) of each site. A false name was reported in 71% of colorectal cancer cases (namely polyp) and in 51% of stomach cases (ulcer and/or polyp). In conclusion, the sensitivity of self-reports of cancer was much lower in this cohort than in the US results except for breast cancer.

Educational Status↗

Food composition and empirical weight methods in predicting nutrient intakes from food frequency questionnaire.

PURPOSE: Although the empirical weight (regression-based) method has theoretical advantages over the traditional food composition method in predicting nutrient levels from food frequency questionnaires (FFQs), the empirical assessments have been limited. METHODS: We compared the validity of the two approaches for a 44-item questionnaire used in a population-based prospective study in Japan. Based on four 7-day diet records and questionnaire responses collected from a subsample of the prospective study (94 men and 107 women), we developed a food composition table and stepwise regression models to predict intakes of energy and 14 nutrients from the questionnaire. RESULTS: When we applied the two methods to an independent population (207 men and 166 women) providing a 3-day diet record and responding to a 36-item dietary questionnaire, energy-adjusted and deattenuated correlation coefficients between the questionnaire and the diet records were not higher for the empirical weight method than for the food composition method; the median (range) was 0.22 (0.07-0.57) for men and 0.23 (-0.09-0.62) for women in the former method, and 0.26 (-0.04-0.58) for men and 0.38 (0.18-0.67) for women in the latter method. CONCLUSIONS: We did not find the improved validity of FFQ by empirical weight method in predicting nutrient intakes.

Cohort Studies↗

Validity and reproducibility of a self-administered questionnaire to determine dietary supplement users among Japanese.

OBJECTIVE: To evaluate reproducibility and validity of a self-administered food frequency questionnaire (FFQ) to determine the dietary supplement use. DESIGN: Questionnaire data were compared with dietary records (DR) in four 7 day periods for validity. FFQ1 and FFQ2 administered at an interval of approximately one year were compared for reproducibility. SETTING AND SUBJECTS: A total of 361 samples were selected for a validation study of a questionnaire from the subgroup of the Japan Public Health Center-based prospective Study on cancer and cardiovascular disease (JPHC Study) cohort II. Categories of dietary supplements in the FFQ were 'multivitamins', 'beta-carotene', 'vitamin C', 'vitamin E', and 'other supplements'. For each category, inquiries were made as to the brand name, frequency and duration of use. A dietary supplement user was defined as a subject who used a dietary supplement one or more times a week for a year or longer. RESULTS: Prevalence of overall supplement use was 10.9%. Percentage agreement between FFQ1 and FFQ2 was 91.7%. Sensitivity and specificity of supplement use by FFQ were 80.6% and 89.2%, respectively. Sensitivity was high for 'vitamin C'. When the self-reported categories were corrected, sensitivity for 'multivitamins' and 'vitamin E' improved. CONCLUSIONS: The FFQ on dietary supplements used for the JPHC 5 y follow-up survey was valid to determine overall use and well-defined dietary supplement use such as vitamin C. Categories must be corrected when determining multivitamin and 'vitamin E'.

Ascorbic Acid↗

Single measurement of serum phospholipid fatty acid as a biomarker of specific fatty acid intake in middle-aged Japanese men.

OBJECTIVE: To assess the utility of serum phospholipid fatty acid (FA) levels as a biochemical indicator of habitual dietary fatty acid intake in Japanese, whose diet is characterized by low fat intake and high intake of n-3 polyunsaturated fatty acids (PUFA) of marine origin. SUBJECTS AND METHODS: Eighty-seven male volunteers from four public health center districts that were part of the Japan Public Health Center based Prospective Study (JPHC Study) cohort I, were included in this study. Habitual intake of fatty acid was obtained by 7 day weighed dietary records four times (in one area only twice) in 1994--1995. Blood was collected twice, in February and August of the same year, and the composition of FA in serum phospholipid was analyzed by gas chromatography. The correlation coefficient between serum phospholipid FA levels and fatty acid intake was calculated. RESULTS: High correlations were observed for eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA), which are marine origin n-3 PUFA (r=0.75, 0.49, 0.50, respectively). No significant correlation was observed for saturated fatty acid (SFA), although the monounsaturated fatty acid (MUFA), palmitoleic acid and oleic acid intake were moderately correlated (r=0.22, 0.35, respectively). The correlations for EPA, DPA and DHA were similar in both samples collected in February and August. CONCLUSIONS: These data suggest that in populations with a high and stable over time intake of n-3 PUFA of marine origin, a single measurement of serum phospholipids reflects the ranking of habitual intake of marine origin n-3 PUFA.

Biomarkers↗

Comparison of selenium status between Japanese living in Tokyo and Japanese brazilians in São Paulo, Brazil.

Selenium (Se) concentrations were determined in human serum, rice and wheat flour sampled in the city of São Paulo, Brazil, and compared with those sampled in Tokyo. Japan. Serum levels of Se were significantly lower in Japanese Brazilians than Japanese living in Tokyo. The samples of rice consumed by Japanese Brazilians in São Paulo contained 22.7 ng Se/g on average, which was about half the selenium level in rice consumed in Tokyo. Rice commonly consumed in São Paulo might be one of the factors to lower the serum level of Se.

Adult↗

Validity and reproducibility of a self-administered food-frequency questionnaire to assess isoflavone intake in a japanese population in comparison with dietary records and blood and urine isoflavones.

Valid food-frequency questionnaires (FFQ) need to be developed to assess isoflavone intake in investigations of its possible association with the lower incidence of breast and prostate cancer in Asian countries. We investigated the validity and reproducibility of isoflavone (daidzein and genistein) intakes from self-administered semiquantitative FFQ used in the JPHC Study (Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases). We also investigated the number of food items that would be sufficient to ensure validity and reproducibility. We collected FFQ, dietary records (DR), blood and urine samples from 215 subjects among JPHC Study participants, estimated isoflavone intakes from FFQ and DR, and measured serum isoflavone concentration and urine isoflavone excretion. For daidzein, mean intakes estimated from FFQ and DR, serum concentration and urine excretion were 18.3 mg/d, 14.5 mg/d, 119.9 nmol/L and 17.0 micromol/d and for genistein, 31.4 mg/d, 23.4 mg/d, 475.3 nmol/L and 14.2 micromol/d, respectively. Results were similar when analyzed by sex. Spearman correlation coefficients for daidzein of energy-adjusted intakes from FFQ with those from DR, serum concentration and creatinine-adjusted urinary excretion were 0.64, 0.31 and 0.43, respectively. Correlations between two FFQ estimates with a 1-y interval were 0.76. Results were similar for genistein. The shorter version of the FFQ with three items (natto, miso and tofu for miso soup) showed a similar correlation. The original FFQ and the shorter versions have sufficient validity and reproducibility to be used in epidemiologic studies.

Diet Records↗

Effect of smoking on serum pepsinogen I level depends on serological status of Helicobacter pylori.

Serum pepsinogen (sPG) levels are used in gastric cancer screening programs. However, modification of sPG levels by smoking habit, according to the status of Helicobacter pylori (H. pylori) infection has been little investigated. This study investigated the effects of smoking on serum levels of pepsinogen I (PG I), pepsinogen II (PG II), and gastrin by IgG titer of antibody against H. pylori (Hp-IgG titer) using the data from 356 current-smokers and 262 non-smokers (133 never-smokers and 129 ex-smokers) in a cross-sectional study of 618 men aged 40 to 49 years. PG I, PG II, PG I / PG II ratio and gastrin were significantly associated with Hp-IgG titer in never-smokers [Spearman's correlation coefficient (95% confidence interval): 0.23 (0.07, 0.39), 0.52 (0.41, 0.63), -0.40 (-0.54,-0.27), and 0.25 (0.10, 0.41), respectively]. However, the correlation coefficients of PG I and PG II decreased in current-smokers, 0.02 (-0.1, 0.13) and 0.32 (0.22, 0.42), respectively. In H. pylori seronegative and low titer cases, the mean PG I level was significantly (P < 0.01) higher in current-smokers, compared with non-smokers. However, in high titer cases, the mean PG I level was lower in current-smokers. Mean PG II and gastrin levels, and PG I / PG II ratio did not differ according to smoking habits by Hp-IgG titer. The gastrin level was significantly correlated with PG II, but not PG I. These data indicate that current smoking influences the serum PG I level depending on Hp-IgG titer and the associations between sPGs and Hp-IgG titer. Gastrin is not involved in the modification of PG I levels by smoking.

Adult↗

Serological Immunoglobulin G antibody titers to Helicobacter pylori in Japanese Brazilian and Non-Japanese Brazilian gastric cancer patients and controls in São Paulo.

Helicobacter pylori (H. pylori) infection is considered a cause of gastric cancer (GC), though evidence for this association is scarce in high-risk areas. Possible case control and/or ethnic differences were investigated as to the presence of H. pylori and its immunogloblin G antibody titer in the multi-ethnic city of São Paulo, where the incidence of GC is relatively high. We performed a cross-sectional comparison of antibody titers to H. pylori in Japanese Brazilian, and non-Japanese Brazilian GC patients and their controls. Japanese Brazilian patients were matched by age, sex and ethnicity with two controls, while non-Japanese Brazilian patients were matched as above with one control. Among Japanese Brazilians, 59 of 93 (63.4%) patients with GC and 127 of 186 (68.3%) controls were positive for H. pylori-specific antibody (odds ratio (OR) = 0.80, 95% confidence interval (CI) = 0.47 - 1.36), while among non-Japanese Brazilians, 171 of 228 patients with GC (75.7%) and 178 of 226 controls (78.8%) were positive (OR = 0.84, 95% CI = 0.54 - 1.30). The median serum antibody titer was lower in cases than in controls in both ethnic groups. A high titer (H. pylori titer > or = 50) was associated with less likelihood of GC for both ethnic groups (for Japanese Brazilians, OR = 0.39, 95% CI = 0.16 - 0.92; for non-Japanese Brazilians, OR = 0.56, 95% CI = 0.31 - 1.02). The high titer can be regarded as a sign of the necessity of eradication, and low titer is regarded as a sign of the necessity of close screening for GC in both ethnic groups, because extended atrophy may cause spontaneous disappearance of H. pylori from the stomach.

Adenocarcinoma↗

Epstein-Barr virus-associated gastric carcinoma in Japanese Brazilians and non-Japanese Brazilians in São Paulo.

The proportion of Epstein-Barr virus-associated gastric carcinoma (EBV-GC) was examined in 149 Japanese-Brazilian and 151 non-Japanese-Brazilian gastric-carcinoma cases using in situ hybridization (ISH) assay to detect EBV-encoded small RNA (EBER), and the results were compared with our referent Japanese data. We found that 4.7% of cases in Japanese Brazilians were EBER-positive. This frequency was slightly lower than that of the referent Japanese, among whom 6.2% of 2038 gastric-carcinoma cases were EBER-positive. On the other hand, the non-Japanese-Brazilian series showed a significantly higher proportion of EBV-GC (11.2%) than the referent group did (P = 0.01). Although EBV-GC was predominant in males among non-Japanese Brazilians (M / F = 3.6, P = 0.047), as was the case in Japanese (M / F = 2.7), Japanese Brazilians did not show such a male predominance. The sex-ratio difference between the Japanese Brazilians and Japanese was statistically significant (P = 0.005). In conclusion, the present study in Japanese Brazilians and Japanese yielded no evidence suggesting any change in the frequency of EBV-GC caused by migration, except the absence of male predominance, which was observed both in Japanese and non-Japanese Brazilians.

Adenocarcinoma↗

Analysis of purine- and pyrimidine-induced vascular responses in the isolated rat cerebral arteriole.

Effects of extraluminal UTP were studied and compared with vascular responses to ATP and its analogs in rat cerebral-penetrating arterioles. UTP, UDP, 2-methylthio-ATP, and alpha,beta-methylene-ATP dilated arterioles at the lowest concentration and constricted them at high concentrations. Low concentrations of ATP dilated the vessels; high concentrations caused a biphasic response, with transient constriction followed by dilation. Endothelial impairment inhibited ATP- and UTP-mediated dilation and potentiated constriction to UTP but not to ATP. ATP- and 2-methylthio-ATP- but not UTP-mediated constrictions were inhibited by desensitization with 10(-6) M alpha,beta-methylene-ATP or 3 x 10(-6) M pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid (PPADS). PPADS at 10(-4) M abolished the UTP-mediated constriction and induced vasodilation in a dose-dependent manner but did not affect the dilation to ATP. These results suggest that in rat cerebral microvessels 1) ATP and 2-methylthio-ATP induce transient constriction via smooth muscle P(2X1) receptors in the cerebral arteriole, 2) UTP stimulates two different classes of P(2Y) receptors, resulting in constriction (smooth muscle P(2Y4)) and dilation (possibly endothelial P(2Y2)), and 3) ATP and UTP produce dilation by stimulation of a single receptor (P(2Y2)).

Adenosine Triphosphate↗

Role of potassium channels in regulation of brain arteriolar tone: comparison of cerebrum versus brain stem.

BACKGROUND AND PURPOSE: Potassium channels are important regulators of resting tone in large cerebral arteries, but their activity and distribution may vary according to vessel location and species studied. In the cerebral microcirculation in vivo, however, these channels appear to be silent at rest. Our goal was to determine the activity of potassium channels of brain arterioles from 2 origins under basal conditions in vitro. METHODS: Penetrating cerebral (40. 9+/-2.2 microm control diameter) and brain stem (36.2+/-1.2 microm) arterioles of rats were prepared from middle cerebral and basilar arteries, respectively. The internal diameter of cannulated and pressurized vessel was monitored with the inverted microscope before and after administration of potassium channel inhibitors. In addition, we studied the effect of nitric oxide synthase inhibition on potassium channel activity. RESULTS: Cerebral and brain stem arterioles were significantly constricted by 4-aminopyridine and low concentration of BaCl(2) but not by glibenclamide. The addition of N:(omega)-nitro-L-arginine to 4-aminopyridine further decreased diameters of both arterioles. Tetraethylammonium ion caused a significant constriction of brain stem but not cerebral arteriole. The brain stem arteriole was further constricted by additional N:(omega)-nitro-L-arginine. CONCLUSIONS: Voltage-dependent and inward-rectifier, but not ATP-sensitive, potassium channels are active under basal conditions of rat cerebral and brain stem arterioles. There is a regional difference in the activity of calcium-activated potassium channels, which, at rest, are open in brain stem but silent in cerebral arterioles. In addition, basal endogenous nitric oxide may not contribute to the activation of voltage-dependent and calcium-activated potassium channels.

4-Aminopyridine↗

Development and validation of specific carotene food composition tables for use in nutritional epidemiologic studies for Japanese populations.

Assessment of dietary intake is important to understand the relationship between nutrition and health. Although the role of specific carotenoids has recently been of great interest, there are no comprehensive food composition tables for intake of specific carotenoids in Japan. We have therefore developed a new carotene food composition table that shows the alpha- and beta-carotene values based on an extensive review of the literature (FCT1). Using a 14- or 28-day diet record data of sample population (n=188), we selected 12 important foods to two carotene intakes. We analyzed the carotene contents of the foods, and developed the another composition table in which the food contents were replaced by the analytical values (FCT2). Carotene intakes of the population were significantly different between these two composition tables. However, the correlations between the dietary intake and the serum concentrations were almost identical, i.e., partial correlations using FCT1/FCT2 were 0.32/0.30 and 0.33/0.36 for alpha-carotene and 0.28/0.28 and 0.30/0.29 for beta-carotene in men and women. The similar correlations with the serum concentrations may indicate an comparable value for ranking individuals between the two tables. However, the results were inconclusive for the estimation of absolute intakes.

Carotenoids↗

Baseline survey of JPHC study--design and participation rate. Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases.

The data collection from cohort subjects at baseline is the core work for prospective study as well as follow-up. We set up 140,420 cohort subjects (68,722 men and 71,698 women) (61,595 in 1990 as Cohort I and 78,825 in 1993 as Cohort II) based on resident registry of 29 districts under 11 Public Health Center areas and baseline survey were submitted for them. The survey consisted of the following three components: (1) self-administered questionnaire survey, (2) collection of blood samples (plasma and buffy coat) for deep-freezed storage and (3) collection of health check-up data. All survey were completed during the first five year of each study. Among all cohort subjects, 113,461 (81%) (53,375 men and 60,086 women, 50,245 in Cohort I and 63,216 in Cohort II) returned the questionnaire and 49,011 (35%) (18,159 men and 30,852 women, 24,637 in Cohort I and 24,374 in Cohort II) provide their blood. The health check-up data were collected from 47,910 (34%) (17,276 men and 30,664 women, 23,311 in Cohort I and 24,599 in Cohort II). These data and blood samples serve as basis for the Japan Public Health Center-based prospective Study on cancer and cardiovascular diseases (JPHC Study).

Adult↗

Study design and organization of the JPHC study. Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases.

The Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases (JPHC Study; formerly called "Koseisho Multipurpose Prospective Cohort Study") began in 1990 (Cohort I) and 1993 (Cohort II). The JPHC Study covers 11 public health center areas throughout Japan and includes a total of 140,420 residents. The study's design includes a baseline survey with a self-administered questionnaire on lifestyle and collection of blood and health checkup data; a follow-up system for mortality, migration, and incidence of cancer and cardiovascular diseases; an additional follow-up survey after 5 and 10 years; and distribution of a newsletter. The JPHC study is expected to provide evidence for the prevention and control of cancer and cardiovascular diseases in the 21st century.

Adult↗