A comparative study on intraocular pressure under various anesthetics in cynomolgus monkeys (Macaca fascicularis).

BACKGROUND: Nonhuman primates (NHPs) are superior model for ocular research due to its morphological and physiological similarities with humans. Thus, the effect of four different anesthetic combinations [ketamine (10 mg/kg), ketamine + xylazine (7 + 0.6 mg/kg), zoletil (4 mg/kg), and zoletil + xylazine (4 + 0.2 mg/kg)] on intraocular pressure (IOP) was determined in cynomolgus monkeys. RESULTS: The administration of ketamine + xylazine or zoletil + xylazine resulted in lower IOP compared to ketamine or zoletil alone. Moreover, the IOP in male monkeys was higher than in females. The difference between the right and left eye was not found. CONCLUSIONS: Anesthetics affected the IOP, and gender differences should be considered when measuring the IOP of nonhuman primates (NHPs).

Repeated intratracheal instillation of zinc oxide nanoparticles induced pulmonary damage and a systemic inflammatory response in cynomolgus monkeys.

Recently, some researchers have demonstrated that inhaled zinc oxide nanoparticles (ZnONPs) induce an acute systemic inflammatory response in workers. Considering nonhuman primates are preferably considered an animal model for translational research due to their proven similarity with humans in terms of genetics and physiology, we intratracheally instilled ZnONPs to cynomolgus monkey for 14 days and identified the toxic mechanism and bioaccumulation. ZnONPs were rapidly ionized or aggregated in a simulated pulmonary fluid, and they attracted neutrophils to the lungs and increased the pulmonary level of inflammatory mediators. Additionally, thickened alveolar walls, fibrin clots, and hemorrhages were observed in the lungs of the monkeys instilled with the higher dose accompanied by cell debris in the alveolar ducts and alveoli. Dark-field microscopy images revealed translocation of ZnONPs into other tissues accompanied by an increase in the relative weight of livers to body weight. In addition, when instilled at the higher dose, the albumin/globulin ratio notably decreased compared to the control, whereas the C-reactive protein (CRP) level was significantly elevated. ZnONPs also clearly induced apoptotic cell death in a 24 h exposure to alveolar macrophages. Taken together, part of inhaled ZnONPs may be ionized in the lung, resulting in acute toxic effects, including cell death and tissue damage, and the rest may move to other tissues in the form of particles, causing a systemic inflammatory response. Based on the proven evidence among workers, we also suggest that the CRP level can be recommended as a biomarker for ZnONPs-induced adverse health effects.

Inhaled underground subway dusts may stimulate multiple pathways of cell death signals and disrupt immune balance.

In this study, we aimed to identify a toxic mechanism and the potential health effects of ambient dusts in an underground subway station. At 24 h exposure to human bronchial epithelial (BEAS-2B) cells (0, 2.5, 10, and 40 µg/mL), dusts located within autophagosome-like vacuoles, whereas a series of autophagic processes appeared to be blocked. The volume, potential and activity of mitochondria decreased in consistent with a condensed configuration, and the percentage of late apoptotic cells increased accompanying S phase arrest. While production of reactive oxygen species, expression of ferritin (heavy chain) protein, secretion of IL-6, IL-8 and matrix metalloproteinases, and the released LDH level notably increased in dust-treated cells (40 µg/mL), intracellular calcium level decreased. At day 14 after a single instillation to mice (0, 12.5, 50, and 200 µg/head), the total number of cells increased in the lungs of dust-treated mice with no significant change in cell composition. The pulmonary levels of TGF-ß, GM-CSF, IL-12 and IL-13 clearly increased following exposure to dusts, whereas that of CXCL-1 was dose-dependently inhibited. Additionally, the population of cytotoxic T cells in T lymphocytes in the spleen increased relative to that of helper T cells, and the levels of IgA and IgM in the bloodstream were significantly reduced in the dust-treated mice. Subsequently, to improve the possibility of extrapolating our findings to humans, we repeatedly instilled dusts (1 time/week, 4 weeks, 0.25 and 1.0 mg/head) to monkeys. The total number of cells, the relative portion of neutrophils, the level of TNF-α significantly increased in the lungs of dust-treated monkeys, and the expression of cytochrome C was enhanced in the lung tissues. Meanwhile, the pulmonary level of MIP-α was clearly reduced, and the expression of caveolin-1 was inhibited in the lung tissues. More importantly, inflammatory lesions, such as granuloma, were seen in both mice and monkeys instilled with dusts. Taken together, we conclude that dusts may impair the host's immune function against foreign bodies by inhibiting the capacity for production of antibodies. In addition, iron metabolism may be closely associated with dust-induced cell death and inflammatory response.

KMRC011, an agonist of toll-like receptor 5, mitigates irradiation-induced tissue damage and mortality in cynomolgus monkeys.

In the study here, the potential applicability of KMRC011 - an agonist of toll-like receptor-5 - as a countermeasure for radiation toxicities was evaluated. Following a single 5.5 Gy total body irradiation (TBI, surface absorbed dose = 7 Gy) of Co60 γ-rays, mortality rates and degrees of pathological lesions that developed over 80 days were compared in monkeys that received TBI only and a group that was injected once with KMRC011 (10 µg/kg) after TBI. Compared to the TBI-only hosts (80%), the death rate was significantly improved by the use of KMRC011 (40%), all deaths in both groups occurred in the period from Days 19-24 post-TBI. Further analysis of monkeys that survived until the end of the experiment showed that AST and ALT levels were elevated only in the TBI group, and that radiation-induced tissue damage was alleviated by the KMRC011 injection. Additionally, expression of cell death-related proteins was lower in tissues from the KMRC011-treated hosts than in those in the TBI-only group. Other measured parameters, including body weight, food uptake, and hematological values did not significantly differ between the two groups over the entire period. The results of this study, thus demonstrate that KMRC011 could potentially be used as a medical countermeasure for the treatment of acute radiation exposure.

Repeated injection of KMRC011, a medical countermeasure for radiation, can cause adverse health effects in cynomolgus monkeys.

High-dose radiation-induced tissue damage is a major limiting factor in the medical application of nuclear technology. Herein, we tested 28-day repeated-dose toxicity of KMRC011, an agonist of toll-like receptor (TLR) 5, which is being developed as a medical countermeasure for radiation, using cynomolgus monkeys. KMRC011 (0.01, 0.02 or 0.04 mg/kg/day) was intramuscularly injected once daily for 4 weeks, and each two monkeys in both control and 0.04 mg/kg/day group were observed for an additional 2-week recovery period. There were no dose-related toxicological changes in mortality, clinical observations, body weight, food consumption, ophthalmological findings, electrocardiographs, coagulation, serum chemistry, organ weights, or urinalysis and urine chemistry. Although treatment-related changes, such as increased white blood cells, increased absolute and relative neutrophils, decreased relative lymphocytes and inflammatory lesions, were noted in the maximum dose group, these findings were not observed after the 2-week recovery period. Further, we considered that the kidneys and heart may be target organs of TLR5 agonists, as well as the spleen, and that autophagic signals can be triggered in tissue damage and the repair process. Importantly, accumulation of p62 protein, an indicator of autophagy, and a decrease of caveolin-1 protein, a regulator of TLR5 protein half-life, were found in both tissues from the highest dose group. Therefore, we conclude that the no-observed-adverse-effect level for KMRC011 may be greater than 0.04 mg/kg/day in male and female monkeys. Additionally, we propose that further studies are needed to identify the molecular signals, which are related to KMRC011-induced adverse effects.

Sequence-dependent DNA condensation as a driving force of DNA phase separation.

The physical properties of DNA have been suggested to play a central role in spatio-temporal organization of eukaryotic chromosomes. Experimental correlations have been established between the local nucleotide content of DNA and the frequency of inter- and intra-chromosomal contacts but the underlying physical mechanism remains unknown. Here, we combine fluorescence resonance energy transfer (FRET) measurements, precipitation assays, and molecular dynamics simulations to characterize the effect of DNA nucleotide content, sequence, and methylation on inter-DNA association and its correlation with DNA looping. First, we show that the strength of DNA condensation mediated by poly-lysine peptides as a reduced model of histone tails depends on the DNA's global nucleotide content but also on the local nucleotide sequence, which turns out to be qualitatively same as the condensation by spermine. Next, we show that the presence and spatial arrangement of C5 methyl groups determines the strength of inter-DNA attraction, partially explaining why RNA resists condensation. Interestingly, multi-color single molecule FRET measurements reveal strong anti-correlation between DNA looping and DNA-DNA association, suggesting that a common biophysical mechanism underlies them. We propose that the differential affinity between DNA regions of varying sequence pattern may drive the phase separation of chromatin into chromosomal subdomains.

The level of vitamin D using the LC-MS/MS method and related factors in healthy Korean postmenopausal women.

AIM: The main purposes of the study were (i) to evaluate serum vitamin D concentration in the forms of 25(OH)D2 , 25(OH)D3 and total 25(OH)D in Korean postmenopausal women using the LC-MS/MS method, which offers increased sensitivity and selectivity; (ii) to determine the relationship between the bone turnover marker, parathyroid hormone (PTH) and 25(OH)D3 , total 25(OH)D separately; and (iii) to determine the factors that may be associated with vitamin D deficiency using body composition analysis and laboratory blood tests. METHOD: A total of 200 postmenopausal women were recruited from November 2012 to March 2014. To control for seasonal ultraviolet exposure time differences in serum 25(OH)D, laboratory tests were performed only from November to March when vitamin D is not synthesized. Independent relationships between 25(OH)D3 , total 25(OH)D and other variables were assessed by multiple regression analysis. RESULTS: The mean serum 25(OH)D2 , 25(OH)D3 and total 25(OH)D levels were 0.51 (±0.44) ng/mL, 14.23 (±7.05) ng/mL and 14.69 (±7.13) ng/mL, respectively. Both 25(OH)D3 and total 25(OH)D were positively correlated with erythrocyte sedimentation rate (ESR), Apo A-I and C-terminal cross-linked telopeptides of type I collagen in Korean postmenopausal women. Both serum 25(OH)D3 and total 25(OH)D were negatively correlated with alkaline phosphatase , PTH and percent body fat. However, osteocalcin showed a negative correlation (r = -0.451; P = 0.041) with only 25(OH)D3 and not with total 25(OH)D (r = -0.417; P = 0.064). CONCLUSION: Both 25(OH)D3 and total 25(OH)D were negatively correlated with PTH, a bone formation marker (alkaline phosphatase) and percent body fat. Both 25(OH)D3 and total 25(OH)D were positively correlated with a bone resorption marker (C-terminal cross-linked telopeptides of type I collagen), ESR and Apo A-I after multiple regression analysis.

Cigarette smoke condensate may disturb immune function with apoptotic cell death by impairing function of organelles in alveolar macrophages.

Considering that cigarette smoke condensate (CSC) is primarily absorbed through the alveoli in the lungs, herein, we used a mouse alveolar macrophage cell line (MH-S cells). After 24 h exposure, CSC decreased dose-dependently cell viability accompanying an increase in intracellular ROS and NO level. CSC structurally or functionally damaged organelles including mitochondria, ER and lysosome and enhanced the expression of proteins related to apoptosis, ER stress and DNA damage accompanying an elevated proportion of annexin V-bound cells. Meanwhile, the expression of certain proteins related to mitochondrial dynamics (OPA1 and DRP1) and autophagy (ATG5) did not overall show significant dose-dependent change in cells exposed to CSC. More importantly, conversion of LC3-I to LC3B-II, a representative marker for autophagy, was also unclear. Considering that intracellular organelles work together in harmony to perform defense mechanism against foreign bodies, we investigated changes in immune response following CSC exposure. The level of IFN-γ and MIP-1α was elevated in CSC-exposed cells, whereas the MCP-1α level decreased. The expression of chemokine receptors (CD195 and CXCR2) and an adhesion molecule (CD54) increased by CSC treatment, the expression of certain antigen presentation-related proteins (MHC class II, CD40, and CD80) were also enhanced. Meanwhile, the expression of CD86, a co-stimulatory molecule for antigen presentation, dose-dependently decreased. In conclusion, we suggest that CSC may induce apoptotic cell death and disturbance in host defense mechanisms by impairing function of cellular components.

The Association Between the Number of Natural Remaining Teeth and Appendicular Skeletal Muscle Mass in Korean Older Adults.

BACKGROUND: The aim of this study was to examine the correlation between the number of remaining natural teeth (NRT) and the appendicular skeletal muscle mass index (SMI) in older adults. METHODS: This study was based on data from the 2008-2010 Korea National Health and Nutritional Examination Surveys. The participants were 2,378 older participants (984 men and 1,394 women) aged over 65 years. Survey dentists conducted oral health examinations, and ASM was measured using dual-energy X-ray absorptiometry. RESULTS: The participants with NRT≥20 had more ASM and SMI than those with NRT<20 in both sexes. SMI was correlated with NRT in men (r=0.018, p<0.001) and in women (r=-0.007, p<0.001). The positive correlation between the NRT and SMI remained significant in men even after adjusting for age, marital status, income, smoking, drinking, physical activity, protein intake, energy intake, calcium intake, body mass index, fasting blood glucose level, medications, and prostheses (ß=0.011, p=0.001). In women, the correlation disappeared after adjustment for smoking, alcohol, physical activity, protein intake, energy intake, calcium intake, marital status, income, fasting basal glucose, medication administration, and prostheses. CONCLUSION: This study showed a correlation between NRT and SMI in those ≥65 years of age in Korea. The relationship persisted in men, but not in women, even after adjusting for confounders.

Ascending aortic diameter is associated with hypertension in Korean men.

PURPOSE: The purpose of this study was to evaluate the association between ascending aortic diameter (AAD) as measured with low-dose chest computed tomography (LDCT) and hypertension in Korean men. METHODS: Korean men (n=1,050) who were screened for lung cancer using LDCT imaging at a health promotion center in Seoul, Korea between January 1 and December 31were recruited for the study. AAD is the longest length of ascending aorta measured from approximately 15 mm above left main coronary ostium to the mid-slice level of the right pulmonary artery. RESULTS: AAD were divided into quartiles, and the degree of hypertension was determined based on the quartiles of the AAD using logistic regression. Odds ratios (OR) for the proportion of hypertension in Q2 (1.70, 95% CI: 1.11-2.59), Q3 (2.72, 95% CI: 1.81-4.09) and Q4 (3.94, 95% CI: 2.63-5.89) were significantly greater than that of Q1 (P for trend < 0.001). Even after controlling for confounding covariates of age, BMI, total cholesterol, HDL-cholesterol, fasting glucose, GGT, ALT, eGFR, smoking status and alcohol intake, there was significant correlation. CONCLUSION: AAD was significantly associated with the degree of hypertension.

The Association between Urinary Sodium Excretion and Metabolic Syndrome in Korean Adults from the 2010-2011 Korean National Health and Nutrition Examination Survey.

BACKGROUND: The sodium intake of Koreans was higher than that recommended by the World Health Organization. Urinary sodium, which is correlated with sodium intake, can be easily calculated by the Tanaka's equation. This study aimed to evaluate the association between urinary sodium and metabolic syndrome in Korean adults using the 2010-2011 Korean National Health and Nutrition Examination Survey (KNHANES). METHODS: A total of 5,870 participants from the 2010-2011 KNHANES were included in this study. Twenty-four hour urinary sodium was calculated by the Tanaka's equation using spot urine. Participants were divided into tertiles based on urinary sodium levels. The association between urinary sodium and metabolic syndrome was analyzed using multivariate logistic regression analysis. RESULTS: The odds ratios (ORs) and 95% confidence intervals (CIs) of metabolic syndrome for the 2nd and 3rd tertile of urinary sodium levels was 1.51 (1.16-1.97) and 1.56 (1.23-1.97) compared to the lowest tertile of urinary sodium in men. The ORs and 95% CIs of metabolic syndrome in women were 1.20 (0.95-1.51) for the 2nd tertile and 2.16 (1.68-2.78) for the 3rd tertile. These associations remained statistically significant, even after adjusting for multiple covariates such as age, education, regular exercise, smoking, and alcohol consumption. CONCLUSION: These findings indicate that urinary sodium is significantly associated with metabolic syndrome in Korean adults.

Uncertainty of current algorithm for bisphosphonate-related osteonecrosis of the jaw in population-based studies: a systematic review.

To assess the relevance of previous epidemiologic studies on bisphosphonate-related osteonecrosis of the jaw (BRONJ), we first conducted a systematic review of large population-based observational studies and evaluated the validity of claims-based algorithms for the identification of BRONJ. Studies containing primary observational epidemiologic data regarding bisphosphonate (BP) exposure and outcomes of osteonecrosis of the jaw were systematically reviewed. Using surrogates for identifying potential BRONJ cases from a population-based hospital registry, validation was performed through medical chart review. Positive predictive value (PPV) was estimated for each diagnostic code and for the overall algorithm utilized. Various strategies to increase PPV were also performed. Seventeen studies were systematically reviewed and presented with variations in study quality as well as inconsistent findings. Moreover, there was a high level of methodological heterogeneity. A total of 1920 patients were identified through the ICD-10 algorithm with potential BRONJ, although only 109 cases were confirmed, corresponding to an overall PPV of 5.68% (95% confidence interval [CI] 4.68-6.81). Only K10.2 (inflammatory conditions of the jaw) exhibited a relatively high PPV of 26.18%, which increased to 74.47% after confinement to BP users. Other strategies to increase PPV value were not effective. Our findings showed that the overall PPV for BRONJ identification was very low, indicating low validity of the current algorithm and possible overestimation of ONJ occurrence. There is an urgent need to develop more reliable and specific operational definitions for the identification of BRONJ cases in large population databases. © 2016 American Society for Bone and Mineral Research.

Metabolic health is more closely associated with prevalence of cardiovascular diseases or stroke than obesity: A cross-sectional study in Korean populations.

Mounting evidence suggests that not all obese subjects are at increased cardiovascular risk. However, the relationship between the metabolically healthy obese (MHO) phenotype and cardiovascular diseases (CVDs) or stroke remains unclear. Therefore, we retrospectively investigated the prevalence of CVDs or stroke according to metabolic health with obese.We studied 3695 subjects (40-85 years) from the Fifth Korean National Health and Nutrition Examination Survey. Participants were divided into 2 groups and 6 subgroups based on the body mass index (BMI) and metabolic syndrome (MetS) components: healthy (exhibiting none of the 5 MetS components) with the followings: healthy-normal weight (BMI < 23 kg/m), healthy-overweight (BMI = 23-24.9 kg/m), and healthy-obese (BMI ≥ 25 kg/m); and unhealthy (exhibiting 2 or more MetS components) with the followings: unhealthy-normal weight, unhealthy-overweight, and unhealthy-obese.In the healthy group (n = 1726), there were 76 CVDs or stroke patients (4.4%), whereas in the unhealthy group (n = 1969), there were 170 (8.6%). The prevalence was significantly different between the 2 groups (P < 0.001). However, the prevalence was not significantly different among healthy subgroups (P = 0.4072). The prevalence in unhealthy subgroups also demonstrated no statistically significant difference (P = 0.3798).We suggest that the prevalence of CVDs or stroke is different between metabolically healthy and unhealthy phenotype. Furthermore, MHO did not reveal higher CVDs or stroke prevalence rather than metabolically healthy other groups. Additional cohort studies are needed to explain causality between CVDs or stroke incidence and subjects exhibiting the MHO phenotype.

Cancer Prevalence among Physicians in Korea: A Single Center Study.

BACKGROUND: There is little research regarding whether working as a physician affects cancer risk. Moreover, there is no research on cancer prevalence among physicians in Korea. This study utilized the Korea National Cancer Incidence Database to determine whether the prevalence of cancer among physicians differs from the prevalence of cancer within the general population. METHODS: We analyzed the medical records of a representative sample of 382 doctors who underwent a health examination between 2010 and 2013 at a health examination center in a Ewha Womans University Medical Center.Cancer incidence was measured as cases that were eventually diagnosed as cancer according to a biopsy. RESULTS: We collected medical records from 382 physicians (mean age, 51.9±8.1 years) and calculated the standardized prevalence ratios compared to the general population. Thirty physicians (9 male and 21 female) were identified as having cancer. Physicians had a significantly higher prevalence of cancer compared to the general population.Cancer prevalence in male physicians was found to be 2.47 times higher than the prevalence expected within the general population (P=0.006). Among female physicians, cancer prevalence was 3.94 times higher than that in the general population (P<0.001). CONCLUSION: This study revealed that physicians had a higher prevalence of cancer compared to the general population in Korea, which suggests that there may be a problem present in the health care of physicians. Changes to the working environment of physicians will be needed to reduce the high prevalence of cancer among physicians.

What is the most appropriate lipid profile ratio predictor for insulin resistance in each sex? A cross-sectional study in Korean populations (The Fifth Korea National Health and Nutrition Examination Survey).

BACKGROUND: Insulin resistance (IR) reduces reactivity of the target organ to blood insulin. Researchers have attempted to evaluate IR using various serum lipid concentration ratios. We aimed to determine the most strongly IR-predictive lipid profile ratios for each sex by studying associations between lipid concentration ratios and IR using data from the fifth Korea National Health and Nutrition Examination Survey (KNHANES V-1) 2010. METHODS: Overall, 8958 individuals participated in health interview and examination surveys. Among them, 1910 individuals who completed physical examinations and 8-h fasting blood tests and were older than 20 years of age were enrolled (929 men and 981 women). The lipid-ratio-related study outcomes were the low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (LDL-C/HDL-C), triglyceride (TG)/HDL-C, and non-HDL-C (LDL-C + TG/5)/HDL-C ratios. We divided subjects into 4 groups according to lipid profile ratio quartiles for a comparison of homeostasis model assessment (HOMA)-IR values. Regression analyses were performed after adjusting for the confounding factors of age, body mass index, and diabetes mellitus history. RESULTS: HOMA-IR values tended to increase significantly along with LDL-C/HDL-C, TG/HDL-C, and non-HDL-C/HDL-C ratios in both sexes. In men, multiple linear regression analyses showed that after adjusting for confounding factors, a significant positive association remained only with the LDL-C/HDL-C ratio (p = 0.0238, R(2) = 0.3605, root mean squared error [MSE] =0.3512). In women, multiple linear regression analyses showed that after adjusting for confounding factors, significant positive associations remained with the LDL-C/HDL-C (p < 0.0001, R-square = 0.2329, root MSE = 0.3776), TG/HDL-C (p = 0.0001, R(2) = 0.2373, root MSE = 0.3766), and non-HDL-C/HDL-C ratios (p < 0.0001, R(2) = 0.2456, root MSE = 0.3745). CONCLUSION: The LDL-C/HDL-C ratio in men and LDL-C/HDL-C, TG/HDL-C, and non-HDL-C/HDL-C ratios in women might be clinically significant predictors of IR in healthy Korean adults. However, additional large-scale studies are required to confirm these findings.

Effects of a Dietary Supplement with Barley Sprout Extract on Blood Cholesterol Metabolism.

Objective. Barley sprout (Hordeum vulgare L.) contains 4.97% fat, 52.6% polysaccharide, and 34.1% protein along with a variety of vitamins, minerals, and polyphenolic compounds. Hexacosanol is one such compound from the barley leaf that might improve cholesterol metabolism by decreasing cholesterol synthesis. Method. Therefore, this study was conducted to investigate the effects of barley sprout extract on serum lipid metabolism in healthy volunteers (n = 51). Subjects were randomly divided into two groups: one group consumed a single capsule of barley leaf extract daily (n = 25, 42.48 ± 13.58 years) and the other consumed placebo capsules (n = 26, 40.54 ± 11.1 years) for 12 weeks. Results. After 12 weeks, total cholesterol and low-density lipoprotein- (LDL-) cholesterol were not lower in the barley sprout extract group compared to the placebo group (p = 0.415 and p = 0.351, resp.) and no differences in clinical or laboratory findings were observed between both groups. Conclusion. Our study failed to show significant lipid-lowering effects of barley sprout extract, possibly due to dosage, duration of therapy, and small sample size. Despite our nonsignificant findings, barley sprout has a possibility as a functional health food; therefore future research is needed.

A cohort study of incident microalbuminuria in relation to HOMA-IR in Korean men.

BACKGROUND: Despite the previous studies showing the relationship between microalbuminuria and insulin resistance, longitudinal effect of insulin resistance on development of microalbuminuria is not clearly identified in non-diabetic population. METHODS: One thousand six hundred three non-diabetic Korean men without microalbuminuria in 2005 had been followed up for the development of microalbuminuria until 2010. Microalbuminuria was evaluated by urine-albumin creatinine ration, and insulin resistance was evaluated by homeostasis model assessment of insulin resistance (HOMA-IR). Cox proportional hazards model was used to estimate the risk for microalbuminuria according to the tertile of HOMA-IR. RESULTS: During 5465.8 person-y of average follow-up, microalbuminuria developed in 76 (4.7%) participants. Incidence of microalbuminuria increased in proportion to the level of HOMA-IR (tertile 1: 3.0%, tertile 2: 4.1%, tertile 3: 7.1%, P<0.001). When the 1st tertile of HOMA-IR was set as reference, hazard ratios and 95% confidence interval were 1.15 (0.56-2.35) and 2.07 (1.05-4.09) for those in the 2nd and 3rd tertiles of HOMA-IR, even after adjusting multiple covariates, respectively (P for linear trend=0.054). CONCLUSIONS: Increased insulin resistance was a predictor of microalbuminuria in Korean men.

Clinical associations between metabolic syndrome and the development of microalbuminuria in Korean men.

AIMS: There have been several studies on the association between metabolic syndrome (MetS) and microalbuminuria. However, none has examined whether MetS is associated with the prospective development of microalbuminuria. Accordingly, we performed a prospective study to evaluate the longitudinal effects of baseline number of MetS traits on the development of microalbuminuria in Korean men. METHODS: 1649 Korean men without microalbuminuria in 2005 were included and followed prospectively until 2010 with the endpoint being the development of microalbuminuria. MetS was defined according to the joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention. Microalbuminuria was evaluated by urine albumin creatinine ratio (UACR). Risk estimations for development of microalbuminuria were analyzed according to the number of MetS traits using multivariate adjusted Cox proportional hazards model. RESULTS: During 5611.8 person-years of follow-up (median 3.40±1.46 years), microalbuminuria developed in 91 (5.5%) participants between 2006 and 2010. After adjusting for multiple covariates, the hazard ratios (95% confidence interval) for development of microalbuminuria comparing 1, 2 and 3-5 MetS traits vs 0 were 2.57 (0.97-6.82), 2.94 (1.09-7.98) and 3.85 (1.37-10.86), respectively. CONCLUSIONS: The number of MetS traits independently associated with the future development of microalbuminuria during the 5-year follow-up period, and MetS per se was an independent risk factor for microalbuminuria.

The association of lung age with smoking status in korean men.

BACKGROUND: Lung age, calculated from sex, forced expiratory volume in one second (FEV1), and height, was developed to illustrate premature changes to the lungs and could be used to motivate smoking cessation. However, this method has not been tested in association with smoking in Korea. The purpose of this study was to investigate the association of lung age with smoking and other factors in Korean males. METHODS: We reviewed the records of 1,100 healthy men who visited a health promotion center at Ewha Womans University Medical Center from January 2008 to June 2009. Lung age was calculated from FEV1 and normal predictive values of spirometry according to age in the Korean population. The difference between lung age and chronological age was evaluated in relation to smoking status, weight, body mass index, waist, muscle mass, fat mass, and exercise. RESULTS: The age difference was significantly higher in current smokers than in non-smokers (12.47 ± 19.90 vs. 7.30 ± 19.52, P < 0.001). Additionally, the age difference was positively correlated with life time pack-year (ß = 0.223; P < 0.001) and fat mass (ß = 0.462; P < 0.001). Lung age increased 1 year for 4.48 pack-year increase or for 2.16% increase in fat mass. CONCLUSION: We found a significant relationship between lung age and both smoking status and fat mass in healthy Korean males. Lung age may be a useful tool for motivating cessation of cigarette smoking and management of risk factors related to obesity.

Serum adiponectin and type 2 diabetes: a 6-year follow-up cohort study.

BACKGROUND: Studies on factors which may predict the risk of diabetes are scarce. This prospective cohort study was conducted to determine the association between adiponectin and type 2 diabetes among Korean men and women. METHODS: A total of 42,845 participants who visited one of seven health examination centers located in Seoul and Gyeonggi province, Republic of Korea between 2004 and 2008 were included in this study. The incidence rates of diabetes were determined through December 2011. To evaluate the effects of adiponectin on type 2 diabetes, the Cox proportional hazard model was used. RESULTS: Of the 40,005 participants, 959 developed type 2 diabetes during a 6-year follow-up. After the adjustment for age, body mass index (BMI), and waist circumference, the risks for type 2 diabetes in participants with normoglycemia had a 1.70-fold (95% confidence interval [CI], 1.21 to 2.38) increase in men and a 1.83-fold (95% CI, 1.17 to 2.86) increase in women with the lowest tertile of adiponectin when compared to the highest tertile of adiponectin. For participants with impaired fasting glucose (IFG), the risk for type 2 diabetes had a 1.46-fold (95% CI, 1.17 to 1.83) increase in men and a 2.52-fold (95% CI, 1.57 to 4.06) increase in women with the lowest tertile of adiponectin. Except for female participants with normoglycemia, all the risks remained significant after the adjustment for fasting glucose and other confounding variables. Surprisingly, BMI and waist circumference were not predictors of type 2 diabetes in men or women with IFG after adjustment for fasting glucose and other confounders. CONCLUSION: A strong association between adiponectin and diabetes was observed. The use of adiponectin as a predictor of type 2 diabetes is considered to be useful.