Taisun Hyun

Zinc status and growth of Korean infants fed human milk, casein-based, or soy-based formula: three-year longitudinal study

To evaluate the effect of feeding methods on growth and zinc nutritional status of infants early in life, we monitored from birth to 36 months in 51 infants who were exclusively fed human milk (HM, n = 20), casein-based formula (CBF, n = 12), or soy-based formula (SBF, n = 19) during the first five months of life. Zinc status was assessed by analyzing serum zinc concentrations and zinc intakes. Zinc contents in HM and formulas were measured. Zinc intake was estimated by weighing infants before and after feeding in the HM group and by collecting formula-intake records in the CBF and SBF groups. After solid foods were introduced, all foods consumed were also included to estimate zinc intake. The growth of infants in all groups was similar to that established for normal Korean infants. Human milk zinc concentrations declined as lactation progressed. Zinc concentrations in all formulas tested in this study were higher than HM and were also higher than those claimed by the manufacturers. During the first twelve months, mean serum zinc concentrations of infants were similar in all groups, although infants in the HM group consistently had the lowest zinc intake among the groups, and the overall zinc intake in infants fed SBF was highest. This finding could be explained by the different zinc bioavailability of HM and formulas. In conclusion, infants fed HM, CBF or SBF has normal growth up to three years of age, although HM contained the lowest zinc concentration followed by CBF, then SBF.

Risk of gastric cancer is associated with PRKAA1 gene polymorphisms in Koreans

AIM To evaluate the association between genetic polymorphisms of the gene encoding AMP-activated protein kinase (PRKAA1) and the risk of gastric cancer. METHODS The study subjects consisted of 477 age- and sex-matched case-control pairs. Genotyping was performed for 5 tag single nucleotide polymorphisms (SNPs): rs13361707, rs154268, rs3805486, rs6882903, and rs10074991. Associations between gastric cancer and putative risk factors (including the SNPs) were analyzed with multivariate conditional logistic regression models, after adjusting for potential confounding factors. Multiple testing corrections were implemented following methodology for controlling the false discovery rate. Gene-based association tests were performed by using the versatile gene-based association study (VEGAS) method. RESULTS In the dominant model, SNPs rs13361707 [odds ratio (OR) = 1.51, 95%CI: 1.07-2.11)], rs154268 (OR = 1.65, 95%CI: 1.22-2.22), rs6882903 (OR = 1.48, 95%CI: 1.09-2.00), and rs10074991 (OR = 1.53, 95%CI: 1.09-2.16) were significantly associated with an increased risk of gastric cancer. In the recessive model, SNPs rs154268 (OR = 1.66, 95%CI: 1.22-2.26), rs3805486 (OR = 0.63, 95%CI: 0.46-0.85), and rs10074991 (OR = 1.47, 95%CI: 1.15-1.88) were significant risk or protective factors for gastric cancer. In the codominant model, the ORs of each of the 5 SNPs were statistically significant. All SNPs in the model showed a dose-response relationship between the minor allele frequency and the risk of gastric cancer. Most notably, subjects with a homozygous minor allele in SNP rs10074991 showed 2.15 times the risk of gastric cancer as subjects without a minor allele. The PRKAA1 gene showed a significant gene-based association with gastric cancer in the VEGAS test. CONCLUSION All 5 tested tag SNPs of the PRKAA1 gene (rs13361707, rs154268, rs3805486, rs6882903, and rs10074991) were significantly associated with gastric cancer.

Additive interactions between PRKAA1 polymorphisms and Helicobacter pylori CagA infection associated with gastric cancer risk in Koreans

Although several studies reported genetic polymorphisms in protein kinase AMP‐activated alpha 1 catalytic subunit (PRKAA1) and their associations with gastric cancer risk, few have evaluated associations between Helicobacter pylori infection and PRKAA1 gene‐environment interactions. Here, we evaluated the effects of interactions between H. pylori infection and PRKAA1 polymorphisms on gastric cancer risk in Koreans. In this hospital‐based case–control study, PRKAA1 genotypes were analyzed and H. pylori infection and CagA status were examined using a serologic method in 846 pairs of gastric cancer patients and controls matched for age and sex. H. pylori seropositivity was associated with a 1.43‐fold [95% confidence interval: 1.12–1.81] increase in the risk of gastric cancer, and CagA low‐positive titers during H. pylori infection increased the risk by 1.85‐fold (95% confidence interval, 1.38–2.48). Significant positive interaction between the PRKAA1 rs13361707 genotype and H. pylori infection was verified on an additive scale [relative excess risk due to interaction, 0.55; 95% confidence interval, 0.05–1.04; P = 0.030], and the gene‐environment interaction between PRKAA1 rs13361707 and CagA status was also statistically significant (relative excess risk due to interaction, 0.50; 95% confidence interval, 0.30–0.70; P < 0.001). Our results indicated that H. pylori infection, CagA status, and PRKAA1 polymorphisms were risk factors for gastric cancer in Koreans, and that the combination of two of these factors rather than their independent effects synergistically increased the risk.

ITGA1 polymorphisms and haplotypes are associated with gastric cancer risk in a Korean population.

AIM To evaluate the association between the genetic polymorphisms and haplotypes of the ITGA1 gene and the risk of gastric cancer. METHODS The study subjects were 477 age- and sex-matched case-control pairs. Genotyping was performed for 15 single nucleotide polymorphisms (SNPs) in ITGA1. The associations between gastric cancer and these SNPs and haplotypes were analyzed with multivariate conditional logistic regression models. Multiple testing corrections were carried out following methodology for controlling the false discovery rate. Gene-based association tests were performed using the versatile gene-based association study (VEGAS) method. RESULTS In the codominant model, the ORs for SNPs rs2432143 (1.517; 95%CI: 1.144-2.011) and rs2447867 (1.258; 95%CI: 1.051-1.505) were statistically significant. In the dominant model, polymorphisms of rs1862610 and rs2447867 were found to be significant risk factors, with ORs of 1.337 (95%CI: 1.029-1.737) and 1.412 (95%CI: 1.061-1.881), respectively. In the recessive model, only the rs2432143 polymorphism was significant (OR = 1.559, 95%CI: 1.150-2.114). The C-C type of ITGA1 haplotype block 2 was a significant protective factor against gastric cancer in the both codominant model (OR = 0.602, 95%CI: 0.212-0.709, P = 0.021) and the dominant model (OR = 0.653, 95%CI: 0.483-0.884). The ITGA1 gene showed a significant gene-based association with gastric cancer in the VEGAS test. In the dominant model, the A-T type of ITGA1 haplotype block 2 was a significant risk factor (OR = 1.341, 95%CI: 1.034-1.741). SNP rs2447867 might be related to the severity of gastric epithelial injury due to inflammation and, thus, to the risk of developing gastric cancer. CONCLUSION ITGA1 gene SNPs rs1862610, rs24321 43, and rs2447867 and the ITGA1 haplotype block that includes SNPs rs1862610 and rs2432143 were significantly associated with gastric cancer.

Preconceptional use of folic acid and knowledge about folic acid among low-income pregnant women in Korea

BACKGROUND/OBJECTIVES Folic acid supplementation before pregnancy is known to significantly reduce the risk of having a baby with neural tube defects (NTDs). Therefore, it is important for women to be aware of the effects of folic acid supplementation before pregnancy. The purpose of this study was to investigate the awareness and preconceptional use of folic acid and to assess the current knowledge about folic acid among low-income pregnant women in Korea. SUBJECTS/METHODS A questionnaire survey was conducted in 2012. Five hundred pregnant women were selected from the waiting list for the Nutriplus program implemented in public health centers using a multistage clustered probability sampling design. Data from 439 women were analyzed after excluding ones with incomplete answers. RESULTS Among women who responded to the questionnaire, 65.6% had heard of folic acid before pregnancy, and 26.4% reported on the preconceptional use of folic acid. Women with a university degree or higher education were more likely to be aware of folic acid and to take folic acid in the preconception period. In a multivariate logistic regression, when age, education level, household income, employment status, gravidity, parity, and folic acid awareness were included in the model, folic acid awareness was a strong predictor of preconceptional folic acid use. As of interview, 85.4% and 77.7% of women were aware of the NTD-preventive role of folic acid and the appropriate time to take folic acid, respectively. The main sources of information on folic acid were healthcare professionals (41.2%), friends and family members (31.2%), and the media (26.5%). CONCLUSIONS Our results suggest that public health strategies are needed to increase the preconceptional use of folic acid among Korean women.

Determinants of neural tube defect (NTD)-protective circulating concentrations of folate in women of child-bearing age in the US post-folic acid fortification era.

We evaluated folate status of child-bearing age women diagnosed with abnormal pap smear in the US post-folic acid (FA) fortification era and assessed the determinants of NTD-protective and supra-physiologic (SP) concentrations of folate. The distribution of 843 women according to NTD-protective concentrations of RBC folate, plasma folate and SP concentrations of plasma folate were tested in relation to demographic and life-style factors. Logistic regression models specified NTD-protective concentrations of RBC and plasma folate or SP concentrations of plasma folate as dependent variables and demographic and life-style factors as independent predictors of interest. More than 82% reached NTD-protective concentrations of RBC and plasma folate and ~30% reached SP concentrations of plasma folate. FA supplement use was associated with having SP concentrations of plasma folate rather than NTD-protective concentrations of folate. African American (AA) women and smokers were significantly less likely to achieve NTD-protective concentrations of RBC and plasma folate. A large majority of women reached NTD-protective concentrations of folate with the current level of FA fortification without using supplementary FA. Therefore, the remaining disparities in AA women and in smokers should be addressed by targeted individual improvements in folate intake.

Awareness, knowledge, and use of folic acid among non-pregnant Korean women of childbearing age

BACKGROUND/OBJECTIVES Folic acid supplementation before pregnancy is known to reduce the risk of neural tube defects. The purposes of this study were to investigate the awareness, knowledge, and use of folic acid supplements along with their associated factors among non-pregnant Korean women of childbearing age. SUBJECTS/METHODS From August 2012 to March 2013, 704 women aged 19–45 years completed a self-administered questionnaire regarding their awareness, knowledge, and use of folic acid as well as questions to identify risk of inadequate folate intake. RESULTS Approximately 67% of women reported that they had heard of folic acid, and 23.7% had knowledge of both the role of folic acid in preventing birth defects and appropriate time for taking folic acid supplements to prevent birth defects. However, only 9.4% of women took folic acid supplements at the time of the survey. Women aged 19–24 years, unmarried women, and women who had never been pregnant were less likely to be aware and knowledgeable of folic acid or take folic acid supplements. In addition, women at high risk of inadequate folate intake were less likely to take folic acid supplements. In a multivariate analysis, women aged 19–24 years, women with a high school diploma or lower education level, and unmarried women were less likely to be aware and have knowledge of folic acid. The percentage of women taking folic acid supplements was significantly higher among knowledgeable women than among unknowledgeable women. CONCLUSIONS These results support our hypothesis that women with knowledge of folic acid are more likely to take folic acid supplements. Therefore, educational programs or campaigns to improve knowledge regarding the importance of folic acid and to promote consumption of folic acid supplements as well as folate-rich foods are needed to target young, less educated, and unmarried women.

In vitro screening for antioxidant, antimicrobial, and antidiabetic properties of some Korean native plants on Mt. Halla, Jeju Island

In this study, Prunus padus, Lonicera caerulea, Berberis amurensis, and Ribes maximowiczianum, which are mainly distributed on Mt. Halla, Jeju Island, have been investigated for their antioxidant, antimicrobial, and antidiabetic activities. The methanol extracts of R. maximowiczianum leaves and P. padus branches exhibited significant and dose-dependent antioxidant activity including electron-donation ability and reducing power. To analyze the antimicrobial activity, each extract was tested by a serial two-fold dilution method against five selected gram-positive bacteria and four gram-negative bacteria, and this suggested that P. padus branches possessed the maximum antimicrobial activity against most of the gram-positive bacteria tested. In addition, the methanol extracts of P. padus branches exhibited the highest α-glucosidase inhibitory activity with an IC50 value of 1.0±0.1 μg/ml, indicating that P. padus is a promising source as a herbal medicine.