Selenium levels and their association with thyroid autoimmunity and severe preeclampsia in pregnancy: Insights from a prospective ideal breast milk cohort study.

Objective: This study aimed to assess selenium status in South Korean pregnant women and its impact on maternal thyroid function and pregnancy outcomes. Methods: 'Ideal Breast Milk (IBM) Cohort Study' included 367 pregnant women out of 442 participants and categorized into three groups based on plasma selenium levels: deficient (< 70 µg/L), suboptimal (70-99 µg/L), and optimal (≥ 100 µg/L). During the second or third trimester, various blood parameters, including selenium, thyroid-stimulating hormone, free T4, free T3, and anti-thyroid peroxidase antibody levels, were measured. Thyroid parenchymal echogenicity was assessed as another surrogate marker for thyroid autoimmunity using ultrasonography. Results: The median plasma selenium was 98.8 (range: 46.7-206.4) µg/L, and 30 individuals (8%) were categorized as deficient, while 164 (45%) were classified in the suboptimal group. Selenium deficiency was associated with markers of autoimmune thyroiditis, including positive anti-thyroid peroxidase antibody results (13.3 (deficient) vs 4.6 (optimal) %, P = 0.031) and thyroid parenchymal heterogeneity on ultrasound (33.3 (deficient) vs 14.6 (suboptimal) vs 17.3 (optimal) %, P = 0.042), independently of gestational age. The incidence of severe preeclampsia was higher in the group not taking selenium supplements, particularly among those with twin pregnancies, compared to the group taking selenium supplements (0 (selenium supplement) vs 9.0 (no supplement) %, P = 0.015). Conclusion: Pregnant women experience mild selenium deficiency, which can lead to significant health issues including maternal thyroid autoimmunity and obstetrical complications during pregnancy. Guidelines for appropriate selenium intake according to the stage of pregnancy and the number of fetuses are needed.

The Effect of Four Weeks Dietary Intervention with 8-Hour Time-Restricted Eating on Body Composition and Cardiometabolic Risk Factors in Young Adults.

Recently, intermittent fasting, also known as time-restricted eating (TRE), has become a popular diet trend. Compared to animal studies, there have been few studies and inconclusive findings investigating the effects of TRE in humans. In this study, we examined the effects of 8 h TRE on body weight and cardiometabolic risk factors in young adults who were mainly active at night. A total of 33 young adults completed the 8 h TRE for 4 weeks. Body composition was measured by bioelectrical impedance analysis at baseline and every 2 weeks, and blood samples were collected at baseline and week 4. Daily dietary records were logged throughout the intervention period. Participants experienced significant changes in body weight (-1.0 ± 1.4 kg), body mass index (-0.4 ± 0.5 kg/m2), and body fat (-0.4 ± 1.9%) after 4 weeks of TRE. When participants were divided into weight loss/gain groups based on their weight change in week 4, fat mass reduction was significantly higher in the weight loss group than in the weight gain group. Regarding cardiometabolic risk factors, levels of fasting insulin and insulin resistance improved in the weight loss group after intervention, but not in the weight gain group. All subjects showed late-shifted sleeping patterns, but no significant differences in sleep duration, sleep quality, or psychological measures between the two groups. When meal frequency and energy proportion were evaluated, the average meal frequency was 2.8 ± 0.5 and energy proportions of breakfast, lunch, dinner, and snacks were 4.5, 39.2, 37.6, and 18.5%, respectively; there were no significant differences between the two groups. However, the saturated fat intake at dinner was lower in the weight loss group (3.1 ± 3.2%, 6.0 ± 2.5% respectively). In conclusion, 8 h TRE can be applied as a lifestyle strategy to manage body weight and cardiometabolic risk factors among young adults with late chronotypes.

In-vitro toxicity study of poly(alkylphenol) as vulcanizing agent.

In this study, cytotoxicity of various novel poly(alkylpehnol) derivatives which, one of constituent for vulcanizing agent, could be adjusted in medical elastic rubber applications were investigated under various conditions of cytotoxicity test. By MTT-assay which according to ISO 10993-5 regulation, we could figure out cell viability of mouse fibroblast in various sample conditions. Furthermore, by Live & Dead Cell assay, we could get colorimetric cell viability via fluorescence images.

Dietary evaluation of a low-iodine diet in Korean thyroid cancer patients preparing for radioactive iodine therapy in an iodine-rich region.

BACKGROUND/OBJECTIVES: Despite the importance of a low-iodine diet (LID) for thyroid cancer patients preparing for radioactive iodine (RAI) therapy, few studies have evaluated dietary intake during LID. This study evaluated the amount of dietary iodine intake and its major food sources during a typical diet and during LID periods for thyroid cancer patients preparing for RAI therapy, and examined how the type of nutrition education of LID affects iodine intake. SUBJECTS/METHODS: A total of 92 differentiated thyroid cancer patients with total thyroidectomy were enrolled from Seoul National University Hospital. All subjects completed three days of dietary records during usual and low-iodine diets before (131)I administration. RESULTS: The median iodine intake was 290 µg/day on the usual diet and 63.2 µg/day on the LID. The major food groups during the usual diet were seaweed, salted vegetables, fish, milk, and dairy products and the consumption of these foods decreased significantly during LID. The mean energy intake on the LID was 1,325 kcal, which was 446 kcal lower than on the usual diet (1,771 kcal). By avoiding iodine, the intake of most other nutrients, including sodium, was significantly reduced during LID (P < 0.005). Regarding nutritional education, intensive education was more effective than a simple education at reducing iodine intake. CONCLUSION: Iodine intake for thyroid cancer patients was significantly reduced during LID and was within the recommended amount. However, the intake of most other nutrients and calories was also reduced. Future studies are needed to develop a practical dietary protocol for a LID in Korean patients.

Household food insufficiency is associated with dietary intake in Korean adults.

OBJECTIVE: To examine the association of food insufficiency with dietary intake and eating and health behaviours. DESIGN: A cross-sectional study. SETTING: Data were obtained from a secondary source, the Fifth Korea National Health and Nutrition Examination Survey (2010-2012). SUBJECTS: The sample size consisted of 15 603 adults over 19 years of age (8898 households). RESULTS: Significant differences in socio-economic factors were observed according to food insufficiency level (P<0·05), but BMI was similar among groups. Regarding macronutrients, lower protein intake and higher carbohydrate intake were found in the severely food-insufficient group, but we found no association with fat intake. Regarding micronutrients, Ca, Fe, vitamin A, thiamin, riboflavin niacin and vitamin C intakes were negatively associated with food insufficiency level (P trend<0·05). Consumption of different food groups, such as meat, fish, eggs and beans, vegetables and fruits, was significantly lower as food insufficiency level decreased after controlling for all possible variables; food group consumption also differed by sex. Overall eating and health behaviours were poorer in the mildly and severely food-insufficient groups, who received more food assistance but less nutritional education. CONCLUSIONS: Our results showed that dietary intake as well as eating and health behaviours are adversely associated with food insufficiency. These findings suggest that specific strategies to help food-insufficient individuals should be developed in order to improve their dietary quality and health status.

Improvement in the technological feasibility of a web-based dietary survey system in local settings.

The feasibility of a dietary survey tool is crucial for successful nutritional assessment via a community survey and for nutritional epidemiology. In 2012, we identified a newly developed computerized dietary survey system, the Diet Evaluation System (DES), which could be successfully applied to a community survey delivered during home visits using notebook computers when the internet environment was adequate, using either a WiBro modem or a smartphone as a tethered modem. In 2013, we retested DES feasibility using various mobile devices and in a larger number of subjects. We conducted a total of 430 interviews, representing two for each of 215 subjects of various ages, using tablet personal computers (PCs) and laptops. In addition, a group discussion with the interviewers was conducted. The interview success rate was improved to 84% (compared to 67% in 2012). Completing each interview took 14 min 1 s, and data processing was conducted automatically. The subjects' age, gender, and the type of mobile device used influenced the DES interview time. This study implies that the DES is an effective one-stop dietary survey system for use in a local setting. The interviewers' group discussion revealed that a one-stop system using the DES is convenient and that DES optimization for tablet PCs and continued database updating is needed.

Osteoporosis and milk intake among Korean women in California: relationship with acculturation to U.S. lifestyle.

The Korean population in the US increased by a third between 2000 and 2010. Korean women in the US report low calcium intake and relatively high rate of fractures. However, little is known about the prevalence of osteoporosis among Korean American women. This paper examined the relationship between prevalence of osteoporosis and milk consumption, and their relationship with acculturation among a representative sample of immigrant California women of Korean descent. Bilingual telephone surveys were conducted from a probability sample (N = 590) in 2007. Lower acculturation significantly related to lower milk consumption for women during the age periods of 12-18 and 19-34 years. Acculturation was related to higher prevalence of osteoporosis among post-menopausal, but not pre-menopausal Korean women in California. Future research should include larger cohorts, objective measures of osteoporosis, other sources of calcium specific to Korean cuisine, and assessment of bone-loading physical activity.

Dietary patterns based on carbohydrate nutrition are associated with the risk for diabetes and dyslipidemia.

Several studies have been conducted on dietary patterns based on carbohydrate nutrition in Asian populations. We examined the cross-sectional associations in dietary patterns based on carbohydrate nutrition, including the glycemic index (GI) with dyslipidemia and diabetes among the Korean adult population. We analyzed 9,725 subjects (3,795 men and 5,930 women, ≥ 20 years) from the Fourth Korea National Health and Nutrition Examination Survey. Dietary information was collected using single 24-hour recall. Reduced rank regression was used to derive dietary patterns from 22 food groups as predictor variables and four dietary factors related to the quantity and quality of carbohydrates as response variables. Two dietary patterns were identified: 1) the balanced pattern was characterized by high intake of various kinds of foods including white rice, and 2) the rice-oriented pattern was characterized by a high intake of white rice but low intake of vegetables, fruits, meat, and dairy products. Both patterns had considerable amounts of total carbohydrate, but GI values differed. The rice-oriented pattern was positively associated with hypertriglyceridemia in men and low high density lipoprotein-cholesterol in both men and women. The balanced pattern had no overall significant association with the prevalence of dyslipidemia or diabetes, however, men with energy intake above the median showed a reduced prevalence of diabetes across quintiles of balanced pattern scores. The results show that dietary patterns based on carbohydrate nutrition are associated with prevalence of dyslipidemia and diabetes in the Korean adult population.

Dietary patterns are associated with physical growth among school girls aged 9-11 years.

The purpose of this study was to identify dietary patterns among Korean elementary school girls based on the change in body mass index (BMI), body fat, bone mineral density (BMD), and bone mineral content (BMC) during 22 months and to explore the characteristics of dietary patterns identified. Girls aged 9-11 years were recruited and 3-day dietary data were collected four times. Subjects with a diet record of 8 or more days and anthropometric data measured at baseline and 22 months later were included (n = 198). Reduced rank regression was utilized to derive dietary patterns using a change in BMI, body fat, and calcaneus BMD and BMC as response variables. Two dietary patterns were identified: the "Egg and Rice" dietary pattern and "Fruit, Nuts, Milk Beverage, Egg, Grain" (FNMBEG) dietary pattern. Subjects who had high score on the FNMBEG pattern consumed various food groups, including fruits, nuts and seeds, and dairy products, whereas subjects in the "Egg and Rice" dietary pattern group did not. Both dietary patterns showed a positive association with change in BMI and body fat. However, subjects who had a higher score on the "Egg and Rice" dietary pattern had less of a BMC increase, whereas subjects who had a higher score on the FMBEG dietary pattern had more increased BMC over 22 months after adjusting for age, body and bone mass, and Tanner stage at baseline. Our results provide evidence that a well-balanced diet contributes to lean body mass growth among young girls.

Gender modifies the relationship between social networks and smoking among adults in Seoul, South Korea.

OBJECTIVE: To evaluate the interaction of gender with social network mechanisms and smoking behaviors in Seoul, South Korea, where smoking is common among men but not women. METHODS: During 2002, telephone surveys were completed with 500 adults drawn from a probability sample in Seoul. Respondents described their smoking status, smoking rate (number of cigarettes smoked per day) and social networks by assessing who discouraged or encouraged smoking (smoking support) or smoked (smoking models). Multivariable regressions were used for analyses. RESULTS: Women encountered significantly less smoking support than men, 88% (95% confidence interval [95% CI], 85-91) versus 70% (95% CI 66-73) net discouragement of smoking in their network. A difference in smoking support from 25 to 75% net discouragement was associated with a 27% (95% CI 9-49) lower probability of smoking among women, significantly stronger (z = 3.18, p < 0.01) than among men who had a 19% (95% CI 8-27) lower probability of smoking. A similar difference in smoking support was associated with male smokers smoking 6.38 (95% CI 0.86-12.30) fewer cigarettes per day, or 2,329 (95% CI 314-4,490) fewer cigarettes per year. The later association could not be observed among women due to the small proportion of female smokers. Smoking models were not significantly associated with any smoking behaviors across genders. CONCLUSIONS: Social network mechanisms were differentially associated with the high smoking prevalence among men and low prevalence among women and should be targeted by interventions tailored to these differences.

Insulin-like growth factor-I, insulin-like growth factor binding protein-3 and risk of benign prostate hyperplasia in the prostate cancer prevention trial.

BACKGROUND: We investigated whether peptides involved in cellular proliferation and apoptosis, [insulin-like growth factor I (IGFI) and its major binding protein (insulin-like growth factor binding protein 3)], predicted risk of benign prostate hyperplasia (BPH). METHODS: We conducted a nested-case-control study in the placebo arm of the prostate cancer prevention trial (PCPT). Cases (n = 727) were men with surgical or medical treatment for BPH; two or more IPSS scores >14; or two scores of at least five points over baseline one of which was >or=12. Controls (n = 727) were frequency matched by age to cases, reported no BPH treatment, and no IPSS score >8. Cases and controls remained on the PCPT placebo and were followed closely until their 7-year PCPT anniversary. Baseline serum was analyzed for IGFI and IGFBP3. Unconditional logistic regression and polytomous regression estimated the multivariate-adjusted odds ratio (OR) for BPH risk. RESULTS: IGFBP3 was inversely and the IGFI:IGFBP3 ratio was positively associated with BPH risk, but findings were statistically significant only for men with severe symptoms (OR = 0.60, 95% CI = 0.40-0.90 for the fifth vs. first quintile of IGFBP3, P-trend = 0.01). Associations did not differ by age (<65 or >or=65 years), and there was a suggestion that the IGFI:IGFBP3 - BPH risk association may be stronger among overweight men. CONCLUSIONS: A high IGFI:IGFBP3 ratio was associated with increased BPH risk, and high serum IGFBP3 was associated with decreased BPH risk among men with severe symptoms. These results confirm findings from other recent studies.

Coffee, tea, colas, and risk of epithelial ovarian cancer.

Associations of coffee, tea, and other caffeinated beverages with ovarian cancer risk remain uncertain. In a population-based study in Washington State, 781 women with epithelial ovarian cancer diagnosed in 2002 to 2005 and 1,263 controls completed self-administered questionnaires detailing consumption of caffeinated and noncaffeinated coffee, teas, and colas and in-person interviews regarding reproductive and hormonal exposures. We assessed risk associated with coffee, tea, and cola drinking and with total caffeine consumption using logistic regression to calculate odds ratios and 95% confidence intervals. Neither caffeinated nor decaffeinated coffees were associated with ovarian cancer risk; also, we observed no association of total caffeine with risk using a combined index that summed intake from coffee, tea, and carbonated soft drinks. Among teas, neither herbal/decaffeinated nor black teas were associated with risk; however, women who reported drinking >or=1 cup/d of green tea had a 54% reduction in risk (P trend = 0.01). Associations of green tea with risk were similar when invasive and borderline cases were considered separately and when Asian women were excluded from analysis. Green tea, which is commonly consumed in countries with low ovarian cancer incidence, should be further investigated for its cancer prevention properties.

Smoking cessation patterns and predictors among adult Californians of Korean descent.

This paper describes smoking cessation among adult California residents of Korean descent, based on a telephone survey (N = 2,830). The overall quit rate (number of former smokers divided by number of ever-smokers) was 55.0% (55.8% among males and 49.6% among females). Acculturation was negatively associated with 90-day abstinence after controlling for demographic, social support, health belief, environmental, lifestyle, and respiratory illness history variables (OR = 0.59, 95% CI = 0.38-0.91). Those with lower acculturation, higher body mass index, a social network discouraging smoking, home smoking restriction, correct beliefs about smoking harm, and significant concern about one's health were most likely to quit smoking for 90 days or longer. Results suggest that social and situational conditions should be included in the design of smoking cessation interventions among Koreans.

Acculturation and health risk behaviors among Californians of Korean descent.

BACKGROUND: This study examined the effects of acculturation on health behaviors among Korean-Americans in California compared to Koreans in Seoul. METHODS: Telephone interviews were conducted with 2,830 Korean-American adults in California (completion rate exceeding 86%) and 500 Korean adults in Seoul (completion of about 50%). RESULTS: Among Korean-Americans, acculturated women were more likely to smoke and drink while acculturated men were more likely to become obese. All Korean-American men reported significantly decreased rates of smoking and drinking compared to Koreans in Seoul. Among both men and women in California, acculturation was associated with high consumption of American foods, and low consumption of traditional Korean foods. CONCLUSIONS: These results indicate that more acculturated Korean-Americans were exposed to greater health risk than those who were less acculturated.