Kyoko Hasegawa

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.European Journal of Clinical Nutrition (2001) 55, 643–650

High Prevalence of Antibodies to Hepatitis A and E Viruses and Viremia of Hepatitis B, C, and D Viruses among Apparently Healthy Populations in Mongolia

ABSTRACT The prevalence of infection with hepatitis A virus (HAV), HBV, HCV, HDV, and HEV was evaluated in 249 apparently healthy individuals, including 122 inhabitants in Ulaanbaatar, the capital city of Mongolia, and 127 age- and sex-matched members of nomadic tribes who lived around the capital city. Overall, hepatitis B surface antigen (HBsAg) was detected in 24 subjects (10%), of whom 22 (92%) had detectable HBV DNA. Surprisingly, HDV RNA was detectable in 20 (83%) of the 24 HBsAg-positive subjects. HCV-associated antibodies were detected in 41 (16%) and HCV RNA was detected in 36 (14%) subjects, none of whom was coinfected with HBV, indicating that HBV/HCV carriers account for one-fourth of this population. Antibodies to HAV and HEV were detected in 249 (100%) and 28 (11%) subjects, respectively. Of 22 HBV DNA-positive subjects, genotype D was detected in 21 subjects and genotype F was detected in 1 subject. All 20 HDV isolates recovered from HDV RNA-positive subjects segregated into genotype I, but these differed by 2.1 to 11.4% from each other in the 522- to 526-nucleotide sequence. Of 36 HCV RNA-positive samples, 35 (97%) were genotype 1b and 1 was genotype 2a. Reflecting an extremely high prevalence of hepatitis virus infections, there were no appreciable differences in the prevalence of hepatitis virus markers between the two studied populations with distinct living place and lifestyle. A nationwide epidemiological survey of hepatitis viruses should be conducted in an effort to prevent de novo infection with hepatitis viruses in Mongolia.

The use of food-frequency questionnaires for various purposes in China

OBJECTIVE To compare various food-frequency questionnaires (FFQs) used in nutritional studies in China for various purposes. DESIGN In Study 1, a simplified FFQ with 17 questions on food was used in a large rural study. In Study 2, a questionnaire consisting of 84 questions on food consumption of 16 food categories was used in a study comparing dietary consumption data and various health indicators of elderly people in four geographical areas in China. In Study 3, a questionnaire with 149 items in 17 food categories is being validated by comparison with data obtained by repeated 24-hour recalls. SETTING Study 1 was carried out in one southern site and a northern site in 1996 to 1997. Study 2 was conducted in four different geographical sites in 1998. The on-going study, Study 3, has been carried out in Jiangsu and Beijing since 1999. SUBJECTS Study 1 included 12 234 rural Chinese adults aged 40 years. There were 546 elderly people in Study 2. Study 3 is collecting data from 300 healthy adults. RESULTS The results of food consumption and nutrient intakes from Study 1 were comparable with those obtained from a previous household dietary survey, in which sensible correlations between diet and diseases were also found. In Study 2, the dietary data from the four geographical areas showed significant differences in food and nutrient intakes among the different areas. The validation of the new FFQ in Study 3 is still going on. CONCLUSION The FFQ is a useful method for the collection of individual food consumption information. The above FFQ forms could be used in studies with different purposes, especially in studying the relationship between diet, nutrition and chronic diseases.

Effect of n−3 fatty acid supplementation on lipid peroxidation and protein aggregation in rat erythrocyte membranes

Human erythrocytes in the circulation undergo dynamic oxidative damage involving membrane lipid peroxidation and protein aggregation during aging. The present study was undertaken to determine the effect of n−3 fatty acid supplementation on lipid peroxidation and protein aggregation in the circulation and also the in vitro susceptibility of rat erythrocyte membranes to oxidative damage. Wistar male rats were fed a diet containing n−6 fatty acid-rich safflower oil or n−3 fatty acid-rich fish oil with an equal amount of vitamin E for 6 wk. n−3 Fatty acid content in erythrocyte membranes of rats fed fish oil was significantly higher than that of rats fed safflower oil. The degree of membrane lipid peroxidation and protein aggregation of rats fed fish oil was not significantly higher than that of rats fed safflower oil when the amounts of phospholipid hydroper-oxides, thiobarbituric acid-reactive substances, and detergent-insoluble protein aggregates were measured. When isolated erythrocytes were oxidized under aerobic conditions in the presence of Fe(III), the degree of membrane lipid peroxidation of erythrocytes from rats fed fish oil was increased to a greater extent than that of rats fed safflower oil, whereas the degree of membrane protein aggregation of both groups was increased in a similar extent. Hence, n−3 fatty acid supplementation did not affect lipid peroxidation and protein aggregation in membranes of circulating rat erythrocytes, and the supplementation increased the susceptibility of isolated erythrocytes to lipid peroxidation, but not to protein aggregation, under the aerobic conditions. If a sufficient amount of vitamin E is supplied, n−3 fatty acid supplementation may give no undesirable oxidative effects on rat erythrocytes in the circulation.

Longevity and Diet in Okinawa, Japan: The Past, Present and Future

Japan has the longest life expectancy at birth (LEB) in the world. Okinawa, Japans poorest prefecture, previously had the highest longevity indices in the country. However, the latest LEB for men in Okinawa is no higher than the national average. The purpose of this study is to examine why the longevity indices in Okinawa were once the highest in Japan, and to examine the reasons for their recent decline. In 1990, in Okinawa, the age-adjusted death rates (ADR) of the three leading causes of death were lower than their national averages. By 2000, the standard mortality ratios (SMR, Japan=100) of heart disease and cerebrovascular disease for both sexes in Okinawa had increased, compared to their 1990 levels. Both of the ADR of ischemic heart disease and the ADR of cerebrovascular disease for men increased to 45.5 and 63.5 in 2000, up from 42.9 and 59.1 in 1990, respectively, and the SMR of ischemic heart disease for men in Okinawa reached 101 in 2000. Consequently, the national ranking of Okinawa prefecture for LEB of men has dropped. As of 1988, in Okinawa, daily intake of meat and daily intake of pulses were both approximately 90 grams, which is about 20% and 30% higher than the national average, respectively. Also, as of 1988, daily intake of green and yellow vegetables in Okinawa was about 50% higher than the national average. However, by 1998, daily meat intake and fat energy ratio had surpassed 100 grams and 30%, respectively, and daily intake of pulses and green and yellow vegetables had declined to the level of the national average. Recently, young Japanese, particularly young men in Okinawa, have shown a tendency to avoid the traditional dishes of stewed meat and champuru.

Improvement in blood lipid levels by dietary sn-1,3-diacylglycerol in young women with variants of lipid transporters 54T-FABP2 and -493g-MTP.

UNLABELLED In a double-blind parallel-group study, serum lipids and visceral fat/total fat ratio in young women (n=49) with variants of lipid transporters, i.e., fatty acid binding protein 2 (FABP2) and microsomal triglyceride transfer protein (MTP), were analyzed by substituting dietary triacylglycerol (TAG) with sn-1,3-diacylglycerol (DAG). All subjects, including some with the hyperlipidemia-prone genotypes Ala54Thr of FABP2 and c-493g of MTP, received DAG or TAG (20 g/day) for 8 weeks. Reductions of serum lipids from weeks 4 to 8 in FABP2-Ala54Thr heterozygotes and MTP -493g homozygotes were significantly different between the DAG and TAG groups (p<0.05, p<0.01). Visceral fat/total fat (%), as determined by computed tomography (CT), was lower in FABP2-Ala54Thr heterozygotes (p<0.05) of the DAG group. The apoCII/CIII ratio was higher in the DAG group than in the TAG group (p<0.01). Other variants of lipid metabolism, including peroxisome proliferator activated receptors (PPARs) alpha and gamma and SREBP cleavage-activating protein (SCAP), were only slightly affected by dietary DAG. CONCLUSION improvement of serum lipid profiles and visceral fat/total fat ratio (CT) was potentiated by DAG intake in subjects with hyperlipidemia-prone genotypes (Ala54Thr heterozygotes of FABP2 and -493g homozygotes of MTP).

Reproducibility and Validity of a Chinese Food Frequency Questionnaire

Abstract Objective This study was design to develop a semi-quantitative Chinese Food Frequency Questionnaire (FFQ) and to conduct a validation study for the questionnaire. Methods Based on the survey experience in recent years, a new Chinese food frequency questionnaire (FFQ) with 149 items in 17 food categories was developed. A validation study on this new FFQ was conducted in Jiangsu and Beijing of China between 1999 and 2001. The period of study covered 1 year and the FFQ was validated by comparing with data obtained by a six repeated 24-hour recalls for 3 consecutive days, or a totally 18-day 24-hour recall throughout the year. A total of 271 healthy adult subjects were enrolled in the study. Food and nutrient intakes measured by the 18-day dietary recalls and food frequency questionnaires (FFQs) were computed in the National Institute for Nutrition and Food Safety, China CDC using the existing nutrition database. The average daily intake of foods and nutrients over the 18-day recall was used to compare with FFQ1 and FFQ2, which was conducted at the beginning and the end of the year, respectively. All statistical analyses were carried out using SAS software version 6.12. Results The reproducibility of FFQ in this study was evaluated at three levels between FFQ1 and FFQ2, i.e. comparison of the mean intake of foods and nutrients; correlation analysis of their intake; and cross-classification and agreement on their corresponding intake. The results showed a high degree of reproducibility for both foods and nutrients. Except for wheat flour and fishes, there were no significant differences in the mean intake of all other foods including rice, other cereals, fresh vegetables, salted vegetables, fresh fruits, nuts, pork, poultry, egg, milk, vegetable oil, soy sauce, salt, and liquor; and this is also true for all nutrients except thiamin. The correlation coefficients ranged from 0.43 to 0.90 for foods and 0.23 to 0.73 for nutrients. Relative validity was tested by comparing the results of food consumption and nutrient intake from both FFQ1 and FFQ2 with those from the average of the 18-day 24-hour recall. The relative validity of FFQ1 was performed in the absence of the possible bias due to a learning effect in FFQ2. This was closer to the real situation where subjects were deprived of any previous experience in quantifying their diet. However, the relative validation of FFQ2 covered the same period as the 24-hour recall. By comparing the mean intake of foods and nutrients between FFQ1 and FFQ2 and the 24-hour recall significant differences were revealed in most foods and nutrients. The crude correlation coefficients between FFQ1 and means of the 24-hour recall ranged from 0.12 to 0.87 for foods and from 0.33 to 0.63 for nutrients. The crude correlation coefficients between FFQ2 and the 24-hour recall ranged from 0.33 to 0.85 for foods and from 0.22 to 0.84 for nutrients. The strongest correlations were found for staple food (rice and wheat flour), pork, poultry and fishes, milk, and liquor. The weakest correlations were found for foods which are not consumed regularly such as potatoes, nuts, legume, and products; and also for fresh vegetables. Adjustment for energy and for attenuation improved correlation for nutrients. The correlation coefficients ranged from 0.27 to 0.86 for FFQ1 and the 24-hour recall and ranged from 0.39 to 0.99 for FFQ2 and the 24-hour recall. Discussion Reproducibility: In conducting a reproducibility evaluation, it is unrealistic to administer the questionnaire at a very short interval, such as in a few days or weeks. When a longer interval of time is used, true changes in dietary intake, as well as variation in response, may lead to reduced reproducibility. This study used one year as an interval between the two interviews which was the most desirable one used in other studies. The reproducibility of FFQ in this study was evaluated in three aspects between FFQ1 and FFQ2, i.e. comparison of the mean intake of foods and nutrients; correlation analysis of their intake; and cross-classification and agreement on their intake A high degree of reproducibility was shown for both food consumption and nutrient intake. Validity: Relative validity was tested by comparing the results of food consumption and nutrient intake from both FFQ1 and FFQ2 with those from the average of the 18-day 24-hour recall. The correlation of FFQ2 with the average of the 18 day 24-hour recalls was generally stronger than that of FFQ1. The relative validity of FFQ1 was performed in the absence of the possible bias due to a learning effect in FFQ2. This was closer to the real situation where subjects were deprived of any previous experience in quantifying their diet. However, the relative validation of FFQ2 covered the same period as the 24-hour recall. Among the available and feasible comparison methods of validating a FFQ, diet records are likely to have the least correlation with FFQ which are due to the restrictions imposed by a fixed list of foods, memory, perception of portion size, and interpretation of questions. These sources of error are minimally shared by diet records because diet records are open-ended, do not depend on memory (foods are recorded on a meal-by-meal basis), and allow direct assessment of portion size. The primary alternative for the use of diet records as a standard of evaluating FFQ is the collection of multiple 24-hour recalls. The results of an evaluation of relative validation depend on several factors which include choice of reference method, the degree of homogeneity of intake values within the population, recall period, and the number of the days recorded. The standard method in our study was a six repeated 24-hour recall for three consecutive days, or a totally 18-day 24-hour recall, over one-year period. Our study subjects were a group of adult residents with a fairly fixed lifestyle. These may partly contribute to stronger correlations obtained in our study. A trend that FFQ overestimates the mean intake for most of the food groups and nutrients included in the study has been observed. There have been few studies to reveal information on over- or under-estimates of both food consumption and nutrient intake by FFQ and the 24-hour recall. The overestimates of both food and nutrient intake in our study may possibly be explained by the fact that the 24-hour recall estimates of food and nutrient intake are derived directly from reports of actual diet of 18 days and that in FFQ the intake comes from summaries or averages of foods consumed during the year and the 18 day 24-hour recall may be not long enough to estimate individual one year diet intake since diet variation exists cross the season and day to day. The results of high degree of reproducibility strongly support the assumption that FFQ could reflect the one year dietary information of the individual. Despite some overestimation of both foods and nutrients by FFQs, agreement on cross-classification is comparable to what other studies have shown, and classification in the same quartile in our study shows a mean of over 45% agreement, while classification in the same and next quartile reveals an mean agreement over 75%. Application: FFQ developed by this study has been applied in several other studies including the Chinese National Nutrition and Health Survey in 2002. Conclusion In this study, the reproducibility and validity of FFQ were all satisfactory. The results have shown that FFQ can be used to classify study subjects according to their food consumption or nutrient intake over a one-year period. These findings have also confirmed that FFQ is an appropriate instrument to measure the usual food consumption and nutrient intake, as well as to assess the dietary patterns of adult Chinese. It could be used in studies with different purposes, especially in studying the relationship between diet, nutrition and chronic diseases.

Single Nucleotide Polymorphism and Lifestyle-Related Diseases in the Asia-Pacific Region: Comparative Study in Okinawa, Palau and Thailand

Genetic differences between Asians and Caucasians may be involved in the rapid increase in lifestyle-related diseases in the Asia-Pacific region that has coincided with Westernisation of diets in the region. In the present study, we assessed correlation between 10 single nucleotide polymorphisms (SNPs) and chronic disease risk factors in age-matched and population-based groups in four Asian-Pacific locations: Okinawa, Palau and Thailand (two areas). The following allelic SNP profiles significantly differed (p<0.01) among the four populations, in both men and women: uncoupling protein 2 (UCP2), uncoupling protein 3 promoter (UCP3p), leptin receptor (LEPR) exon 6, and angiotensinogen (AGTa-20c). Multiple regression analyses showed significant associations between SNPs and clinical data. For men, these associations were between β3 adrenergic receptor (β3AR) and diastolic blood pressure (DBP) (p<0.01), UCP3p and total cholesterol (p<0.01), UCP2 and age (p<0.05), and AGTa-20c and age (p<0.01). For women, these associations were between LEPR exon 14 and body mass index (BMI) (p<0.05), UCP2 and systolic blood pressure (p<0.05), UCP3p and DBP (p<0.05), UCP2 and DBP (p<0.01), apolipoprotein E (Apo-E)nd total cholesterol (p<0.01), β3AR and triglyceride (p<0.05), AGTa-20c and triglyceride (p<0.05), and UCP2 and age (p<0.05). These results illustrate the interrelationships among SNPs and risk factors in the Asia-Pacific including China and Japan.