Membraneless Ionic Liquid Droplet Nanoprobe for Oxygen Sensing and Gas Phase Scanning Electrochemical Microscopy.

A novel membraneless oxygen sensing nanoprobe was developed based on a hanging drop ionic liquid electrochemical cell. An ultrasmall (<500 nm) working electrode and small volume electrochemical cell allowed for an impressively low detection limit of ∼13 ppm and a response time less than 100 ms, which is unusually fast for an electrochemical gas sensor. The oxygen sensor was stable for hours of operation and, owing to the membraneless design, was easily regenerable when fouled. The pulled capillary form factor of the nanoprobe was found compatible with scanning probe techniques, the demonstration of which was made by application as a tip electrode in gas phase scanning electrochemical microscopy (SECM). In the SECM experiments, the oxygen nanoprobe exhibited micrometer scale spatial resolution with ease. This unique probe design developed here may potentially be engineered into versatile sensors for various volatile molecules other than oxygen, such as those pertinent to hazard analysis and biomedical diagnosis.

Carbon-free high-performance cathode for solid-state Li-O2 battery.

The development of a cathode for solid-state lithium-oxygen batteries has been hindered in practice by a low capacity and limited cycle life despite their potential for high energy density. Here, a previously unexplored strategy is proposed wherein the cathode delivers a specific capacity of 200 milliampere hour per gram over 665 discharge/charge cycles, while existing cathodes achieve only ~50 milliampere hour per gram and ~100 cycles. A highly conductive ruthenium-based composite is designed as a carbon-free cathode by first-principles calculations to avoid the degradation associated with carbonaceous materials, implying an improvement in stability during the electrochemical cycling. In addition, water vapor is added into the main oxygen gas as an additive to change the discharge product from growth-restricted lithium peroxide to easily grown lithium hydroxide, resulting in a notable increase in capacity. Thus, the proposed strategy is effective for developing reversible solid-state lithium-oxygen batteries with high energy density.

[Cold atmospheric pressure plasma for the treatment of acute and chronic wounds]. / Kaltes Atmosphärendruckplasma zur Behandlung akuter und chronischer Wunden.

BACKGROUND: Besides acute wounds (through trauma or surgical interventions), chronic wounds comprise a relatively large and heterogeneous group of diseases. These include leg ulcers with venous disease greatly prevailing arterial disease, diabetic foot syndrome, and pressure ulcers. Due to a considerable treatment resistance against such therapies, new and effective, additive treatment options especially for chronic wounds are needed. Wound treatment with cold atmospheric plasma (CAP) constitutes such an innovative option. OBJECTIVES: Current research regarding the efficacy of cold plasma for healing of acute and chronic wounds is summarized. MATERIALS AND METHODS: The literature on CAP applications in wound healing has been screened and reviewed. RESULTS: With CAP, several effects that promote wound healing can be simultaneously applied in one application. On the one hand, CAP exerts a strong and broad antimicrobial activity against biofilm. On the other hand, the plasma cocktail, which consists of reactive nitrogen and oxygen species, UV, and charged particles (electrical current), mediates tissue-stimulating, blood flow-promoting, and anti-inflammatory effects. Marked germ reduction on wounds and accelerated wound healing have already been convincingly demonstrated in controlled clinical studies. CONCLUSIONS: The comprehensive CAP study landscape with structured case report summaries and randomized case-control studies allows the conclusion that CAP is safe, effective, and easy to handle for wound treatment. The utilization of CAP in addition to standard wound treatments is starting to enter routine clinical practice.

Effects of a conscious sedation dressing on pain and anxiety in pediatric burn patients.

AIM: This study examined the effects of a conscious sedation dressing on pain and anxiety in pediatric patients with burns. METHODS: This was a quasi-experimental study, using a nonequivalent control group. Using convenience sampling, the participants were assigned to two groups, an experimental group (n = 10), which comprised children who received a conscious sedation dressing, and a control group (n = 13), which comprised children who received general dressing care. To minimize the risk of contamination between the two groups, the sampling was sequentially performed. RESULTS: The children in the experimental group showed significantly lower levels of pain (U = 3.29, d = 1.00, P = .003) and physiological responses, as evidenced by lower systolic blood pressures, diastolic blood pressures, pulse rates, and respiratory rates than the control group (systolic blood pressures: t = 5. 05, d = 1.22, P < .001; diastolic blood pressures: t = 2.12, d = 0.93, P = .046; pulse rates: t = 2.28, d = 1.00, P = .033; and respiratory rates: t = 2.47, d = 1.09, P = .022). CONCLUSION: The application of a conscious sedation dressing may alleviate pain and anxiety for pediatric burn patients.

Time course of the changes in right and left ventricle function and associated factors after transcatheter closure of atrial septal defects.

OBJECTIVE: The purpose of this study was to evaluate the changes in right ventricle (RV) and left ventricle (LV) function after transcatheter atrial septal defect (ASD) closure and to assess the influence of the age and the amount of shunt. DESIGN: Retrospective study PATIENTS: Fifty-three adult patients who underwent transcatheter closure were enrolled, then divided into subgroups according to the age (< 40 years vs ≥ 40 years), and the amount of shunt flow (QpQs < 2.5 vs QpQs ≥ 2.5). OUTCOME MEASURES: Two-dimensional tissue Doppler imaging was performed in a four-chamber view at the basal ventricular septum (VS) and tricuspid valve annulus (TVA) before and at 1 month and 6 months after closure. Myocardial velocities, the myocardial performance index (MPI), and isovolumic acceleration (IVA) were assessed. RESULTS: At the TVA, the MPI decreased slightly and then greatly increased at 6 months after closure (P = .002). The IVA improved in all patients (P < .001), and the E'/A' ratio decreased, especially in the old age group (P = .031) and larger shunt group (P = .035). At the VS, S' and the IVA decreased and had not recovered until 6 months in the old age (P = .02) and larger shunt (P = .02). The Qp/Qs showed a significant reverse correlation with a decrease in the E'/A' at the TVA (r = -0.37, P = .008), and age of patient was correlated with a decrease in the IVA at the VS (r = -0.32, P = .019). The age at closure (ß = -0.36, P = .002), the Qp/Qs ratio (ß = -0.45, P = .01), and RV MPI changes (ß = -7.64, P < .001) were found to be associated factors with IVA decrease at the VS. CONCLUSIONS: After ASD closure, RV global function might be impaired. In elderly patients and patients with a large shunt, impairment of LV contractility developed until 6 months after closure. Close long-term observation is required after closure, especially in old-age patients with a large shunt.

Heparanase-induced shedding of syndecan-1/CD138 in myeloma and endothelial cells activates VEGFR2 and an invasive phenotype: prevention by novel synstatins.

Multiple myeloma arises when malignant plasma cells invade and form multiple tumors in the bone marrow. High levels of heparanase (HPSE) correlate with poor prognosis in myeloma patients. A likely target of the enzyme is the heparan sulfate (HS) proteoglycan syndecan-1 (Sdc1, CD138), which is highly expressed on myeloma cells and contributes to poor prognosis in this disease. We find that HPSE promotes an invasive phenotype mediated by the very late antigen-4 (VLA-4, or α4ß1 integrin) in myeloma cells plated on either fibronectin (FN) or vascular endothelial cell adhesion molecule-1 (VCAM-1), ligands that are prevalent in the bone marrow. The phenotype depends on vascular endothelial cell growth factor receptor-2 (VEGFR2), which is aberrantly expressed in myeloma, and is characterized by a highly protrusive lamellipodium and cell invasion. HPSE-mediated trimming of the HS on Sdc1 and subsequent matrix metalloproteinase-9-mediated shedding of the syndecan exposes a juxtamembrane site in Sdc1 that binds VEGFR2 and VLA-4, thereby coupling VEGFR2 to the integrin. Shed Sdc1 can be mimicked by recombinant Sdc1 ectodomain or by a peptide based on its binding motif, which causes VLA-4 to re-orient from the lagging edge (uropod) to the leading edge of migrating cells, couple with and activate VEGFR2. Peptides (called 'synstatins') containing only the VLA-4 or VEGFR2 binding sites competitively inhibit invasion, as they block coupling of the receptors. This mechanism is also utilized by vascular endothelial cells, in which it is also activated by HPSE, during endothelial cell tube formation. Collectively, our findings reveal for the first time the mechanism through which HPSE modulates Sdc1 function to promote both tumor cell invasion and angiogenesis, thereby driving multiple myeloma progression. The inhibitory synstatins, or inhibitors of HPSE enzyme activity, are likely to show promise as therapeutics against myeloma extravasation and spread.

Association of human microRNAs miR-22 and miR-491 polymorphisms with panic disorder with or without agoraphobia in a Korean population.

BACKGROUND: The possible involvement of microRNAs (miRNA) in psychiatric disorders has been recently recognized. Several miRNA polymorphisms have been found to be associated with panic disorder (PD) in European populations. However, the association of miRNA polymorphisms on PD has not been reported in Asian populations. We evaluated the effect of miR-22 and miR-491 polymorphisms on susceptibility to PD in a Korean population. METHODS: Genotyping for four polymorphic variants of the primary miRNA (pri-miRNA) regions of miR-22 (rs8076112 and rs6502892) and miR-491 (rs4977831 and rs2039391) was performed using blood samples of 341 Korean patients with PD and 229 healthy control subjects. To evaluate PD phenotypes, the Panic Disorder Severity Scale (PDSS) and Anxiety Sensitivity Inventory-Revised (ASI-R) were administered. RESULTS: Three single-nucleotide polymorphisms (SNPs) were found to be associated with PD: rs8076112 miR-22 and rs4977831 and miR-491 rs2039391. The rs8076112C/rs6502892C haplotypes of miR-22 and rs4977831G/rs2039391G and rs4977831A/rs2039391A haplotypes of miR-491 were significantly overrepresented in patients with PD than in healthy control subjects. In combination analysis, miR-22 rs8076112AC/rs6502892CC and rs8076112CC/rs6502892CC and miR-491 rs4977831AG/rs2039391AA were more frequent in patients with PD. Among the phenotype assessments, ASI-R scores were significantly associated with miR-22 rs6502892 in the subgroup with the agoraphobic phenotype. LIMITATIONS: The results should be considered preliminary due to the relatively small sample size and the selection of only four SNPs. CONCLUSIONS: This is the first report to show possible associations of miR-22 and miR-491 with genetic susceptibility to PD in a Korean population.

Association between folate metabolism-related polymorphisms and colorectal cancer risk.

Folate has essential roles in DNA synthesis, repair and methylation. Folate metabolism-related gene variants may modulate the levels of this vitamin and affect the cancer risk. Thus, whether these polymorphisms play an important role in carcinogenesis, particularly colorectal cancer (CRC) development, has been a subject interest. The present study investigated the association between polymorphisms in the methylenetetrahydrofolate reductase (MTHFR), thymidylate synthase (TS) and the reduced folate carrier 1 (RFC1) genes and CRC risk. Polymorphisms in MTHFR (677C>T and 1298A>C), TS [1494del6 and the TS enhancer region (TSER)] and RFC1 (-43T>C, 80G>A and 696C>T) were characterized using polymerase chain reaction-restriction fragment length polymorphism in 477 CRC cases and 514 controls. Although no polymorphisms were significantly associated with the CRC risk in the overall sample, significant associations between folate metabolism-related polymorphisms and CRC risk were identified in the stratified analyses. The MTHFR 677CT/1298AC and MTHFR 1298AC+CC/TSER 2R3R genotypes in the presence of plasma folate levels ≤4.12 ng/ml were associated with significantly increased CRC risk. In addition, individuals with the MTHFR 677TT/TSER 3R3R or MTHFR 677/TSER 3R3R/TS 1494 0bp6bp+6bp6bp genotypes and diabetes mellitus (DM) were at an increased risk for CRC. Therefore, the data suggest that i) MTHFR polymorphisms combined with low plasma folate levels and ii) polymorphisms in folate metabolism-related genes combined with metabolic syndrome risk factors (hypertension and DM) increase the odds of developing CRC.

Genetic variants in 3'-UTRs of methylenetetrahydrofolate reductase (MTHFR) predict colorectal cancer susceptibility in Koreans.

Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) play important roles in tumor development, progression, and metastasis. Moreover, recent studies have reported that a number of 3'-UTR polymorphisms potentially bind to specific microRNAs in a variety of cancers. The aim of this study was to investigate the association of four MTHFR polymorphisms, 2572C>A [rs4846049], 4869C>G [rs1537514], 5488C>T [rs3737967], and 6685T>C [rs4846048] with colorectal cancer (CRC) in Koreans. A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of MTHFR 3'-UTR polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis or TaqMan allelic discrimination assay. We found that MTHFR 2572C>A, 4869C>G, and 5488C>T genotypes were substantially associated with CRC susceptibility. Of the potentially susceptible polymorphisms, MTHFR 2572C>A was associated with increased homocysteine and decreased folate levels in the plasma based on MTHFR 677CC. Our study provides the evidences for 3'-UTR variants in MTHFR gene as potential biomarkers for use in CRC prevention.

Association of reduced folate carrier-1 (RFC-1) polymorphisms with ischemic stroke and silent brain infarction.

Stroke is the second leading cause of death in the world and in South Korea. Ischemic stroke and silent brain infarction (SBI) are complex, multifactorial diseases influenced by multiple genetic and environmental factors. Moderately elevated plasma homocysteine levels are a major risk factor for vascular diseases, including stroke and SBI. Folate and vitamin B12 are important regulators of homocysteine metabolism. Reduced folate carrier (RFC), a bidirectional anion exchanger, mediates folate delivery to a variety of cells. We selected three known RFC-1 polymorphisms (-43C>T, 80A>G, 696T>C) and investigated their relationship to cerebral infarction in the Korean population. We used the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to analyze associations between the three RFC-1 polymorphisms, disease status, and folate and homocysteine levels in 584 ischemic stroke patients, 353 SBI patients, and 505 control subjects. The frequencies of the RFC-1 -43TT, 80GG, and 696CC genotypes differed significantly between the stroke and control groups. The RFC-1 80A>G substitution was also associated with small artery occlusion and SBI. In a gene-environment analysis, the RFC-1 -43C>T, 80A>G, and 696T>C polymorphisms in the ischemic stroke group had combined effects with all environmental factors. In summary, we found that the RFC-1 -43C>T, 80A>G, and 696T>C polymorphisms may be risk factors for ischemic stroke.

Effects of total vitamin A, vitamin C, and fruit intake on risk for metabolic syndrome in Korean women and men.

OBJECTIVES: The question of whether the consumption of antioxidants prevents and alleviates metabolic syndrome (MetS) by reducing insulin resistance remains controversial. The aim of this study was to assess whether the intake of vitamin A (including ß-carotene), vitamin C, fruits, or vegetables was negatively associated with MetS in Korean adults aged ≥ 20 y. METHODS: We conducted a cross-sectional study of 27,656 adults ≥ 20 y of age who participated in the 2007-2012 Korean National Health and Nutrition Examination Survey. Daily intake of vitamin A and vitamin C was assessed by 24-h recall, and the consumption of fruits and vegetables was determined using a food frequency questionnaire. Odds ratios (ORs) for MetS were calculated for log2-transformed vitamin A and C intake values and for the interaction of sex with vitamin A and C intake, after covariate adjustment. RESULTS: Interactions were seen between total vitamin A and C intake and sex for MetS. With a twofold increase in total vitamin A and C intake in women, the ORs (95% confidence intervals) for metabolic syndrome were 0.942 (0.901-0.985) and 0.933 (0.883-0.987), indicating decreases of 5.8% and 6.7% in MetS, respectively. There were no equivalent decreases in men. Women in the second and highest tertiles of fruit intake exhibited 17.5% and 21.8% lower incidences of MetS, respectively, compared with women in the lowest tertile. CONCLUSIONS: The intake of total vitamin A and C, as well as moderate and high fruit intake, may have alleviated MetS in women, but not in men, in a representative sample of the general South Korean population.

Association study of five functional polymorphisms in matrix metalloproteinase-2, -3, and -9 genes with risk of primary ovarian insufficiency in Korean women.

OBJECTIVE: Primary ovarian insufficiency (POI) is diagnosed clinically by increased follicle-stimulating hormone (FSH) levels and estradiol (E2) deficiency. A previous report suggests a possible association matrix metalloproteinase (MMP) and estrogen signaling pathway; however, there are no reports of MMP genetic associations with POI. STUDY DESIGN: Blood samples were collected from 374 karyotypically normal study participants consisting of 138 patients with POI (46, XX; mean age ± standard deviation [SD], 31.7 ± 3.51 years) and 236 control subjects (46, XX; 32.2 ± 3.50 years). Five functional polymorphisms in MMP-2 (-1575G>A [rs243866] and -1306C>T [rs243865]), MMP-3 (-1612 5A/6A [rs3025058]), and MMP-9 (-1562C>T [rs3918242] and 2678G>A [rs17576]) genes were genotyped using polymerase chain reaction-restriction fragment length polymorphism assays in a cohort of 236 controls and 138 POIs. RESULTS: MMP-2 -1306CT+TT was associated with POI occurrence. Moreover, relatively lower serum estradiol levels were detected in healthy women with the MMP-2 -1575GA+AA/MMP-2 -1306CT+TT and MMP-2 -1306CT+TT/MMP-9 2678GG combination genotypes. CONCLUSIONS: MMP-2 -1306C>T polymorphism may contribute to an increased POI prevalence in Korean women. Further studies are needed to confirm the genetic associations in other ethnic populations.

Interplay between 3'-UTR polymorphisms in the vascular endothelial growth factor (VEGF) gene and metabolic syndrome in determining the risk of colorectal cancer in Koreans.

BACKGROUND: Polymorphisms in angiogenesis-related genes and metabolic syndrome (MetS) risk factors play important roles in cancer development. Moreover, recent studies have reported associations between a number of 3'-UTR polymorphisms and a variety of cancers. The aim of this study was to investigate the associations of three VEGF 3'-UTR polymorphisms (1451C > T [rs3025040], 1612G > A [rs10434], and 1725G > A [rs3025053]) and MetS with colorectal cancer (CRC) susceptibility in Koreans. METHODS: A total of 850 participants (450 CRC patients and 400 controls) were enrolled in the study. The genotyping of VEGF polymorphisms was performed by TaqMan allelic discrimination assays. Cancer risks of genetic variations and gene-environment interactions were assessed by adjusted odds ratios (AORs) and 95% confidence intervals (CIs) of multivariate logistic regression analyses. RESULTS: VEGF 1451C > T was significantly associated with rectal cancer risk (Dominant model; AOR =1.58; 95% CI = 1.09 - 2.28; p = 0.015) whereas VEGF 1725G > A correlated with MetS risk (Dominant model; AOR =1.61; 95% CI =1.06 - 2.46; p = 0.026). Of the gene-environment combined effects, the interaction of VEGF 1451C > T and MetS contributed to increased rectal cancer risk (AOR = 3.15; 95% CI = 1.74 - 5.70; p < .001) whereas the combination of VEGF 1725G > A and MetS was involved with elevated colon cancer risk (AOR = 2.68; 95% CI = 1.30 - 1.55; p =0.008). CONCLUSIONS: Our results implicate that VEGF 1451C > T and 1725G > A may predispose to CRC susceptibility and the genetic contributions may be varied with the presence of MetS.

Lead-induced impairments in the neural processes related to working memory function.

BACKGROUND: It is well known that lead exposure induces neurotoxic effects, which can result in a variety of neurocognitive dysfunction. Especially, occupational lead exposures in adults are associated with decreases in cognitive performance including working memory. Despite recent advances in human neuroimaging techniques, the neural correlates of lead-exposed cognitive impairment remain unclear. Therefore, this study was aimed to compare the neural activations in relation to working memory function between the lead-exposed subjects and healthy controls. METHODOLOGY/PRINCIPAL FINDINGS: Thirty-one lead-exposed subjects and 34 healthy subjects performed an n-back memory task during MRI scan. We performed fMRI using the 1-back and 2-back memory tasks differing in cognitive demand. Functional MRI data were analyzed using within- and between-group analysis. We found that the lead-exposed subjects showed poorer working memory performance during high memory loading task than the healthy subjects. In addition, between-group analyses revealed that the lead-exposed subjects showed reduced activation in the dorsolateral prefrontal cortex, ventrolateral prefrontal cortex, pre supplementary motor areas, and inferior parietal cortex. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that functional abnormalities in the frontoparietal working memory network might contribute to impairments in maintenance and manipulation of working memory in the lead-exposed subjects.

Iron deficiency increases blood cadmium levels in adolescents surveyed in KNHANES 2010-2011.

Discrepancies have been reported in the relationships between iron and cadmium concentrations. The distribution of blood cadmium concentrations was assessed in a representative sample of Korean adolescents participating in the Korean National Health and Nutritional Examination Survey (KNHANES) 2010-2011, and the association between blood cadmium and iron concentrations was determined. This study was based on data from KNHANES, in which a rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the noninstitutionalized civilian population in South Korea. Serum ferritin was categorized as low (<15.0 µg/L), low normal (15.0-<30.0 µg/L for girls, 15.0-<50.0 µg/L for boys), or normal (≥30.0 µg/L for girls, ≥50.0 µg/L for boys), and the association between serum ferritin and blood cadmium concentrations was assessed after adjustment for various demographic and lifestyle factors. The geometric mean (GM) of blood cadmium was significantly higher among both boys and girls in the low than in the normal ferritin group. After controlling for covariates, multiple regression analysis showed that blood cadmium concentration was inversely correlated with serum ferritin concentration in both boys and girls. In conclusion, iron deficiency is associated with increased blood cadmium concentrations in a representative sample of Korean adolescents, as evaluated in KNHANES.

Interleukin-1beta -511T>C genetic variant contributes to recurrent pregnancy loss risk and peripheral natural killer cell proportion.

OBJECTIVE: To identify whether interleukin gene polymorphisms are risk factors for idiopathic recurrent pregnancy loss (RPL) in Korean women. DESIGN: Case-control study. SETTING: Hospital-based study. PATIENT(S): A cohort of 385 idiopathic RPL patients and 232 controls with Korean ethnicity. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Genotyping was assessed with a polymerase chain reaction-restriction fragment length polymorphism assay. We examined polymorphisms in three interleukin (IL) genes: IL-1ß, IL-4, and IL-10. RESULT(S): The IL-1ß -511T>C polymorphism was associated with RPL (-511TT vs. -511CC: adjusted odds ratio 1.826; 95% confidence interval 1.130-2.953). Allelic gene-gene interaction analysis revealed that the T/B2/G (IL-1ß/IL-4/IL-10) allele combination was only detected in the RPL group (adjusted odds ratio 20.046; 95% confidence interval 1.188-338.204). The proportion of peripheral natural killer cells was higher in patients with the IL-1ß -511C allele compared with the -511T allele. CONCLUSION(S): According to these results, IL-1ß -511T>C may be a predisposing factor to RPL susceptibility. However, the mechanism underlying the function of IL-1ß -511T>C in RPL remains to be determined, and further studies are needed to improve understanding of the roles of IL-1ß -511T>C, using a larger and more heterogeneous cohort.

Association between common genetic variants of α2A-, α2B- and α2C-adrenoceptors and the risk of silent brain infarction.

Silent brain infarction (SBI) is an asymptomatic cerebrovascular disorder. The aim of the present study was to investigate the association between adrenoceptor-α2 (ADRA2) gene polymorphisms and SBI. A total of 361 patients with SBI and 467 healthy control subjects were examined. The polymerase chain reaction was performed to genotype the ADRA2A 1780G>A, ADRA2B 301-303 insertion/deletion (I/D) and ADRA2C 322-325I/D polymorphisms. The frequency of the ADRA2C 322-325I/D polymorphism was significantly different between patients with SBI and control subjects. When interaction analyses were performed for vascular risk factors, the ADRA2C 322-325ID genotype increased the risk for SBI in the presence of hypertension and elevated plasma homocysteine levels. The ADRA2C 322-325ID genotype and plasma homocysteine levels showed a significant synergistic effect for SBI. In addition, the ADRA2A 1780AA genotype was associated with elevated plasma homocysteine levels. Although further analysis of the association between ADRA2 polymorphisms and clinical risk factors of SBI is required, the present study of a limited set of SBI risk factors with ADRA2 polymorphisms provides the first evidence of the involvement of ADRA2 gene family members in the development of SBI. Further studies using larger and more heterogeneous populations are required to validate the association of ADRA2 polymorphisms with SBI.

Associations between blood mercury levels and subclinical changes in liver enzymes among South Korean general adults: analysis of 2008-2012 Korean national health and nutrition examination survey data.

INTRODUCTION: We herein used data from the Korean National Health and Nutritional Examination Survey (KNHANES) 2008-2012 to examine the associations between blood mercury levels and subclinical changes of liver function in a representative sample of the adult Korean population. METHODS: This study was based on data obtained from KNHANES, in which a rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the non-institutionalized civilian population in South Korea. The associations between subclinical hepatic changes and blood mercury levels were assessed after adjustment for various demographic and lifestyle factors. RESULTS: Multivariate linear regression analyses revealed that each doubling of blood mercury increased serum aspartate transaminase (AST) by 0.676U/L and serum alanine transaminase (ALT) by 1.067U/L. The mean differences (95% CI) in serum AST and ALT between the lowest and highest quartiles were statistically significant at 1.249 (0.263-2.235)U/L and 2.248 (0.648-3.848), respectively. Logistic regression analysis showed that the odd ratios for having serum AST and ALT levels above the median were statistically significant in both the models according to the increase of blood mercury. The risks of having serum AST and ALT levels higher than the median among subjects in 4th quartile of blood mercury were 1.524 and 1.947, respectively. DISCUSSION: The present findings show that subclinical changes of liver function are associated with blood mercury levels. This is the first study to show an association between blood mercury levels and mild liver dysfunction, as a possible proxy measure of nonalcoholic fatty liver disease (NAFLD), in Asian population.

Iron deficiency increases blood lead levels in boys and pre-menarche girls surveyed in KNHANES 2010-2011.

INTRODUCTION: We present data from the Korean National Health and Nutritional Examination Survey (KNHANES) 2010-11 on the distribution of blood lead levels, and examine their association with iron deficiency in a representative sample of the adolescent Korean population. METHODS: This study was based on data obtained from KNHANES, in which a rolling sampling design was used to perform a complex, stratified, multistage probability cluster survey of a representative sample of the non-institutionalized civilian population in South Korea. Serum ferritin was categorized into three levels: low (serum ferritin <15.0µg/L), low normal (serum ferritin 15.0-30.0µg/L for girls and 15.0-50.0 for boys), and normal (serum ferritin ≥30.0µg/L for girls and ≥50.0 for boys), and its association with blood lead levels was assessed after adjustment for various demographic and lifestyle factors. RESULTS: The geometric mean (GM) of blood lead in the low serum ferritin group was significantly higher than that in the normal group among boys but not girls. After controlling for covariates, multiple regression analysis showed that blood lead was inversely correlated with serum ferritin levels in boys and pre-menarche girls only. DISCUSSION: The present study shows that iron deficiency increases blood lead levels in a representative sample of the male and pre-menarche female adolescent population, as evaluated in KNHANES. The confounding effect of estrogen on blood lead levels should be considered.