Interactive associations of smoking and physical activity with metabolic syndrome in adult men in Korea.

Introduction: This study aimed to investigate the association of smoking and physical activity (PA) with metabolic syndrome (MetS) in adult men in Korea. Methods: This study analyzed data of 7,229 adult men aged 19-64 years obtained from the 2014-2021 Korea National Health and Nutrition Examination Survey (KNHANES). Information on smoking habits was obtained using KNHANES data, while that on total PA (TPA), leisure-time PA (LTPA), and occupational PA (OPA) was collected using the Global Physical Activity Questionnaire. Smoking status was classified into non-smokers and smokers, and PA was categorized into three groups (total, leisure time, and occupational) according to the time spent engaging in moderate or high-intensity PA areas. The diagnosis of MetS was based on the Adult Treatment Program III of the National Cholesterol Education Program and Koreans' waist circumference criteria. Results: Logistic regression revealed that the risk of MetS was significantly lower in non-smokers than in smokers, even after adjusting for all covariates. The risk of MetS was significantly lower in individuals who engaged in at least 150 min of moderate- and high-intensity TPA or LTPA per week than in those who did not engage in PA. Furthermore, smokers who engaged in at least 150 min of moderate- to high-intensity TPA and LTPA per week had a significantly lower risk of MetS than those who did not engage in PA. Meanwhile, OPA was not associated with MetS. Conclusion: The findings suggest that engaging in moderate- to high-intensity TPA or LTPA for at least 150 min per week attenuates the risk of MetS caused by smoking.

Predictors of Changes in Cognitive Function in Older Korean Adults: The 2006-2018 Korean Longitudinal Study of Aging.

Cognitive decline with normal aging varies widely among individuals. This study aimed to investigate predictors of longitudinal changes in cognitive function in community-dwelling Korean adults aged 65 years and older. Data from 727 older adults who participated in the Korean Longitudinal Study of Aging (KLoSA) survey from 2006 (baseline) until 2018 (seventh wave) were used. Cognitive performance was assessed with the Korean Mini-Mental State Examination. The participants were retrospectively classified into normal cognition, mild cognitive impairment, and moderate/severe cognitive impairment. Education, income, religion, living area, alcohol intake, smoking, physical activity, handgrip strength, functional dependency, depression, comorbidity, medications, fall experience, and unintentional weight loss were included as covariates. A linear mixed regression analysis showed that a steeper decline in cognitive function over time was significantly associated with parameters of poor socio-economic status, health conditions, and unhealthy behaviors. Individuals with mild cognitive impairment or moderate/severe cognitive impairment were likely to have steeper cognitive declines compared with individuals with normal cognition. The current findings of the study showed that age-related cognitive decline was multifactorial in older Korean adults.

Effect of core and surface area toward hydrogen gas sensing performance using Pd@ZnO core-shell nanoparticles.

A versatile hydrogen gas sensor is fabricated using Pd@ZnO core-shell nanoparticles (CSNPs), which were synthesized through a hydrothermal route. Effect of oxidation behavior of Pd core to hydrogen sensing is also investigated for Pd@ZnO CSNPs. Accordingly, Pd@ZnO-2 sensor (core-shell sample was calcined in argon) demonstrates the best performance with respect to Pd@ZnO-1 (core-shell sample was calcined in air) and pure ZnO. It shows a much higher response (R = Ra/Rg = 22) than those of Pd@ZnO-1 (12) and pure ZnO (7) sensors with faster response and recovery times (1.4 and 7.8 min) to 100 ppm hydrogen at 350 °C. In addition, Pd@ZnO-2 sensor owns high selectivity to hydrogen among interfering target gases. Improvement can be attributed to the high content of metallic Pd0 species in CSNPs as calcined in argon. Thereby, a higher Pd metallic content (77%) still remains in Pd@ZnO-2 compared to Pd@ZnO-1 (56%), which in turn modulates the resistance of sensors as exposed to air and target gas, thus enhancing gas sensing activity. High BET surface area of core-shell materials provides plenty of active sites for accelerating the sensing reactions as well.

Cardiorespiratory Fitness is Inversely Associated with Risk of Low Bone Mineral Density in Older Korean Men.

Little is known regarding the association between physical fitness and bone health in older Korean men. This study investigated the relationship between estimated cardiorespiratory fitness (eCRF) and bone mineral density (BMD). This cross-sectional study included 2715 Korean men aged 50 years and older selected from those who participated in the 2008-2011 Korea National Health and Nutritional Examination and Survey. eCRF was obtained using a sex-specific algorithm developed on the basis of age, body mass index, resting heart rate, and physical activity and classified into low, middle, and high categories. Femoral neck BMD was assessed by dual X-ray absorptiometry. Odds ratios (OR) and 95% confidence intervals (CI) for osteopenia, osteoporosis, and low BMD were calculated for eCRF categories in models fully adjusted for age, waist circumference, education, income, smoking, heavy alcohol intake, serum vitamin D, serum parathyroid hormone, and dietary intake of energy, protein, calcium, and vitamins A and C. Overall, eCRF levels were positively associated with BMD and negatively with prevalence of osteopenia, osteoporosis, and low BMD. Logistic regression showed inverse trends in the risks of osteopenia (high vs. low: OR = 0.692; 95% CI, 0.328-0.517; p = 0.049) and low BMD (high vs. low: OR = 0.669; 95% CI, 0.497-0.966; p = 0.029) by eCRF category in models fully adjusted for all the measured covariates. The current findings suggest that maintaining high eCRF via regular physical activity may contribute to attenuation of age-related loss of BMD and decreased risk for low BMD in older Korean men.

Involuntary Weight Loss and Late-Life Depression in Korean Older Adults.

BACKGROUND: To investigate the association between involuntary weight loss (IWL) and late-life depression (LLD) in a population-based cohort study. METHODS: Data (N=6945) obtained from the 2008 baseline and 2011 follow-up assessments of the Living Profiles of Older People Survey in Korea were used. Changed body weight between the 2008 and 2011 was classified into stable weight (<-5% ∼ <+5%), lightweight loss (≥ -5% ∼ <-10%), moderate weight loss (≥ -10%), lightweight gain (+≥5 ∼ <+10%), and moderate weight gain (≥+10%). RESULTS: Compared to the stable weight group, the moderate weight loss group had a higher risk of LLD (odds ratio=1.99, 95% confidence interval=1.61-2.46, P<0.001) even after adjustments for covariates, including age, BMI, education, income, life of solitude, smoking, physical activity, dependent aging, comorbidity, and cognitive function. CONCLUSION: IWL is significantly associated with LLD in Korean older adults, implying the prognostic importance of IWL for presenting mental health issues later in life.

Non-exercise based estimation of cardiorespiratory fitness is inversely associated with metabolic syndrome in a representative sample of Korean adults.

BACKGROUND: This study investigated the association between non-exercise based estimation of cardiorespiratory fitness (eCRF) and metabolic syndrome (Mets) in Korean adults aged 18 years and older (13,400 women and 9885 men). METHODS: Data from the 2008 and 2011 Korea National Health and Nutrition Examination Surveys IV and V in South Korea were analyzed. eCRF was assessed with a previously validated procedure. Participants were classified into 5 categories from the lowest quantile to the highest quantile based on individual eCRF distributions. RESULTS: The findings showed an independent and inverse association between eCRF and Mets in women and men separately. Individuals in the highest eCRF category (quantile 5) had a significantly lower prevalence of Mets (14.5 and 14.8% for women and men, respectively) compared with their counterparts (40.4 and 46.4% for women and men, respectively) in the lowest eCRF category (quantile 1), and the association showed a graded response, with the quantiles 2, 3, and 4 also significantly associated with a lower prevalence of Mets compared with the quantile 1. Furthermore, the prevalence of Mets in the highest quantile compared with the lowest quantile remained statistically significant in both men (p < 0.05) and women (p < 0.05) even after adjustments for age, body mass index, skeletal muscle index, smoking, heavy drinking, vitamin D, caloric intake, and dietary intakes of carbohydrates, fats, and proteins. CONCLUSION: The findings support a preventive role for eCRF against Mets in Korean adults.

Non-Exercise Based Estimation of Cardiorespiratory Fitness Mediates Associations between Comorbidities and Health-Related Quality of Life in Older Korean Adults with Diabetes.

This study investigated whether non-exercise-based estimation of cardiorespiratory fitness (eCRF) mediates the association between health-related quality of life (HRQoL) and comorbidities in older Korean adults with diabetes. A total of 1371 Korean adults (56% women) aged 60 years and older with diabetes was drawn from those who participated in the 2008-2011 Korea National Health and Nutrition Examination Surveys IV and V. Data on comorbidities included hypertension, heart disease (acute myocardial infarction or angina), stroke, arthritis, and chronic renal disease. HRQoL was assessed using the EuroQoL group, which consists of a health-status descriptive system and a visual analogue scale. eCRF was determined with sex-specific algorithms. Age, sex, household income, education level, marital status, smoking, alcohol consumption, and regular exercise were additionally measured as covariates. HRQoL found to be inversely associated with number of comorbidities and positively associated with increasing eCRF category (from low to high) in older Korean patients with diabetes. The Sobel mediation test showed a significant indirect effect (Z = -4.632, p < 0.001), and the result of a bootstrap procedure corroborated the Sobel test result: a non-zero range in the 95% bias-corrected confidence interval (95% CI -1.104 to -0.453) indicated that eCRF mediates the impact of comorbidities on HRQoL. Overall, the current findings suggest that enhancing CRF can facilitate positive outcomes, including better HRQoL, for patients with diabetes.

Association of nonalcoholic fatty liver disease with serum vitamin D levels in combination of physical fitness in korean older adults.

The prevalence of non-alcoholic fatty liver disease (NAFLD) tends to increase with age, but little is known regarding relations between the risk of NAFLD in older adults and serum vitamin D (25-hydroxyvitamin D) and physical fitness levels. The aim of this study was to investigate the relationship between NAFLD risk and serum vitamin D levels combined with physical fitness in elderly adults using a non-invasive diagnostic approach. We enrolled 533 Korean older adults (80.8 % women), aged 65 years or older in this cross-sectional study. NAFLD in absence of another cause of liver disease was defined according to the ZJU and NAFLD liver fat (LFS) score. Physical fitness was assessed using a senior fitness test protocol. Logistic regression analysis was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) of NAFLD for different combinations of serum vitamin D and physical fitness levels. According to the ZJU (OR: 3.073, CI: 1.285-7.350, p = 0.012) and LFS (OR = 2.443, CI = 1.071-5.572, p = 0.034), individuals with serum vitamin D < 30 ng/ml and poor physical fitness had a significantly higher risk of NAFLD than individuals with serum vitamin D ≥ 30 ng/ml and high fitness (reference, OR = 1), even after adjustments for age, sex, smoking, alcohol consumption and physical inactivity. However, there was no significant association after adjustment for additional metabolic diseases. Our findings suggest that the maintenance of appropriate levels of serum vitamin D and/or high physical fitness and the monitoring metabolic diseases can help reduce the risk of NAFLD in older adults.

Lifestyle Risk Factors and All-Cause and Cardiovascular Disease Mortality: Data from the Korean Longitudinal Study of Aging.

This study examined the association between lifestyle risk factors and all-cause and cardiovascular disease (CVD) mortality in 9945 Korea adults (56% women) aged 45 years and older. Smoking, heavy alcohol intake, underweight or obesity, physical inactivity, and unintentional weight loss (UWL) were included as risk factors. During 9.6 ± 2.0 years of follow-up, there were a total of 1530 cases of death from all causes, of which 365 cases were from CVD. Compared to a zero risk factor (hazard ratio, HR = 1), the crude HR of all-cause mortality was 1.864 (95% CI, 1.509-2.303) for one risk factor, 2.487 (95% confidence interval, CI, 2.013-3.072) for two risk factors, and 3.524 (95% CI, 2.803-4.432) for three or more risk factors. Compared to a zero risk factor (HR = 1), the crude HR of CVD mortality was 2.566 (95% CI, 1.550-4.250) for one risk factor, 3.655 (95% CI, 2.211-6.043) for two risk factor, and 5.416 (95% CI, 3.185-9.208) for three or more risk factors. The HRs for all-cause and CVD mortality remained significant even after adjustments for measured covariates. The current findings showed that five lifestyle risk factors, including smoking, at-risk alcohol consumption, underweight/obesity, physical inactivity, and UWL, were significantly associated with an increased risk of all-cause and CVD mortality in Korean adults.

Association between Obesity and Carotid Intima-Media Thickness in Korean Office Workers: The Mediating Effect of Physical Activity.

BACKGROUND: Obesity and physical inactivity are associated with higher prevalence of cardiovascular disease (CVD). OBJECTIVE: This study investigated the association between obesity and carotid intima-media thickness (CIMT) stratified by physical activity (PA) in Korean office workers. METHODS: Data obtained from 914 office workers aged 21-60 years (347 women) were used. Resting blood pressures, body mass index (BMI), and waist-to-height ratio (WHtR) were measured. PA was assessed using the international physical activity questionnaire. CIMT was assessed with a carotid artery ultrasonography. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence interval (CI) of obesity stratified by weekly PA for an abnormally increased CIMT. RESULTS: Logistic regression analyses showed that those who were overall obese (OR=2.50, 95% CI=1.60-3.91, P<0.001) or central obese (OR=2.08, 95% CI=1.29-3.40, P=0.003) had significantly higher estimated risks of having an abnormally increased CIMT even after adjustments for age, sex, smoking, alcohol consumption, resting blood pressures, and history of hypertension, diabetes, and hyperlipidemia, as compared with those who were not overall or central obese (OR=1). A multivariate linear regression suggested that age (P<0.001), sex (P=0.002), hypertension (P=0.014), smoking (P=0.054), BMI (P<0.001), and physical activity (P=0.011) were important determinants of abnormally elevated CIMT in this study population. CONCLUSION: The current findings suggest that the risk of obesity for an abnormally increased CIMT is significantly modulated by demographics as well as lifestyle-related risk factors including smoking and physical inactivity in Korean office workers.

Physical activity and all-cause mortality in Korean older adults.

BACKGROUND: The association between physical activity (PA) and all-cause mortality may be modulated by potential confounders. AIM: To investigate the association between weekly PA and all-cause mortality in a population-based prospective study. SUBJECTS AND METHODS: The study sample included Korean older adults aged 60 years and older who participated in baseline assessments (n = 15 416) in 2008 and completed follow-up visits in 2011 (n = 14,976). Primary outcome was 3-year all-cause mortality. RESULTS: Compared with sufficiently active individuals (with Hazard Ratio (HR) = 1), completely inactive and insufficiently active individuals had a significantly higher risk of all-cause mortality (HR = 2.086, 95% CI = 1.639-2.655, p < 0.00 and HR = 1.644, 95% CI = 1.013-2.668, p = 0.044, respectively), even after adjustments for age and sex, health-related behaviour factors (i.e. smoking, alcohol intake and nutritional risk), cognitive impairment and components of frailty phenotype (i.e. involuntary weight loss, exhaustion and slowness). In addition, the inverse association between PA and all-cause mortality is differently modulated by potential confounders, including age, sex, smoking, depressive symptoms, cognitive impairment and involuntary weight loss. CONCLUSION: PA was inversely and independently associated with all-cause mortality in Korean older adults.

Crystal structure of the PDZ domain of mouse Dishevelled 1 and its interaction with CXXC5.

Dishevelled (Dvl) plays a crucial role in Wnt signaling by interacting with membrane-bound receptors and downstream molecules through its PDZ domain. CXXC5 is one of the key molecules that interacts with Dvl and negatively regulates the Wnt/ß-catenin pathway in osteoblast differentiation. Recently, the Dvl-CXXC5 interaction has been identified as an excellent target for osteoporosis treatment. Therefore, it is desirable to have detailed structural information for the Dvl-CXXC5 interaction. Although solution structures of the Dvl1 PDZ domain have been reported, a high-resolution crystal structure would provide detailed sidechain information that is essential for drug development. Here, we determined the first crystal structure of the Dvl-1 PDZ domain at a resolution of 1.76 Å, and compared it with its previously reported solution structure. The Dvl1 PDZ domain crystal belonged to the space group H32 with unit-cell parameters a = b = 72.837, c = 120.616, α = ß = 90.00, γ = 120.00. The crystal structure of Dvl1 PDZ shared its topology with the previously reported structure determined by nuclear magnetic resonance (NMR); however, the crystal structure was quite different from the solution structure in both the secondary structural region and the ligand-binding pocket. Molecular modeling based on NMR and X-ray crystallographic data yielded detailed information about the Dvl1/CXXC5 interaction, which will be useful for designing inhibitors.

New structural insight of C-terminal region of Syntenin-1, enhancing the molecular dimerization and inhibitory function related on Syndecan-4 signaling.

The PDZ domain-containing scaffold protein, syntenin-1, binds to the transmembrane proteoglycan, syndecan-4, but the molecular mechanism/function of this interaction are unknown. Crystal structure analysis of syntenin-1/syndecan-4 cytoplasmic domains revealed that syntenin-1 forms a symmetrical pair of dimers anchored by a syndecan-4 dimer. The syndecan-4 cytoplasmic domain is a compact intertwined dimer with a symmetrical clamp shape and two antiparallel strands forming a cavity within the dimeric twist. The PDZ2 domain of syntenin-1 forms a direct antiparallel interaction with the syndecan-4 cytoplasmic domain, inhibiting the functions of syndecan-4 such as focal adhesion formation. Moreover, C-terminal region of syntenin-1 reveals an essential role for enhancing the molecular homodimerization. Mutation of key syntenin-1 residues involved in the syndecan-4 interaction or homodimer formation abolishes the inhibitory function of syntenin-1, as does deletion of the homodimerization-related syntenin-1 C-terminal domain. Syntenin-1, but not dimer-formation-incompetent mutants, rescued the syndecan-4-mediated inhibition of migration and pulmonary metastasis by B16F10 cells. Therefore, we conclude that syntenin-1 negatively regulates syndecan-4 function via oligomerization and/or syndecan-4 interaction, impacting cytoskeletal organization and cell migration.

Association of sarcopenia and physical activity with femur bone mineral density in elderly women.

PURPOSE: This study examined the association of femur bone mineral density (BMD) with body composition and physical activity in elderly women. METHODS: This was a cross sectional study involving 119 women with mean age of 73.1±5.5 years. Body composition parameters including body mass index (BMI), percent of body fat (%BF), appendicular skeletal muscle mass (ASM) index and femur BMD was measured by dual-energy X-ray absorptiometry (DXA). Physical activity was assessed by the uniaxial accelerometer for 7 consecutive days including weekends. Based on femur BMD T-scores, subjects were classified as optimal group, osteopenia group, and osteoporosis group. Based on ASM index, subjects were classified as normal group and sarcopenia group. According to WHO recommendations of physical activity for elderly, the subjects were classified as active group or inactive group. Logistic regression analyses were used to determine the odds ratio (OR) for osteopenia and osteoporosis. RESULTS: There were linear decreases for body composition parameters including weight (P=.023), BMI (P=.039), lean mass (P=.032), ASM index (P=.007) and physical activity parameters including daily of step (P<.001), low intensity physical activity (P<.001), moderate intensity physical activity (P=.001) across femur BMD levels. Compared to the normal group (OR=1), the sarcopenia group had a significantly higher OR (OR=4.823; P=.042), and the inactive group had a significantly higher OR (OR=5.478; P=.005) having osteopenia and osteoporosis when compared to the active group (OR=1). CONCLUSION: The findings of this study suggested that physical activity along with a healthy nutrition should be promoted as a preventive strategy against osteopenia and osteoporosis in elderly women.

Au@Cu2O core-shell nanoparticles as chemiresistors for gas sensor applications: effect of potential barrier modulation on the sensing performance.

Au@Cu2O core-shell nanoparticles (NPs) were synthesized by a solution method at room temperature and applied for gas sensor applications. Transmission electron microscopy (TEM) images showed the formation of Au@Cu2O core-shell NPs, where 12-15 nm Au NPs were covered with 60-30 nm Cu2O shell layers. The surface plasmon resonance (SPR) peak of Au NPs was red-shifted (520-598 nm) after Cu2O shell formation. The response of Au@Cu2O core-shell NPs was higher than that of bare Cu2O NPs to CO at different temperatures and concentrations. Similarly, the response of Au@Cu2O core-shell NPs was higher than that of bare Cu2O NPs for NO2 gas at low temperature. The improved performance of Au@Cu2O core-shell NPs was attributed to the pronounced electronic sensitization, high thermal stability and low screening effect of Au NPs.

Disintegration of amyloid fibrils of alpha-synuclein by dequalinium.

alpha-Synuclein is the major amyloidogenic component observed in the Lewy bodies of Parkinson's disease. Amyloid fibrils of alpha-synuclein prepared in vitro were instantaneously disintegrated by dequalinium (DQ). Double-headed cationic amphipathic structure of DQ with two aminoquinaldinium rings at both ends turned out to be crucial to exert the disintegration activity. The defibrillation activity was shown to be selective toward the fibrils of alpha-synuclein and Abeta40 while the other beta2-microglobulin amyloid fibrils were not susceptible so much. Besides the common cross beta-sheet conformation of amyloid fibrils, therefore, additional specific molecular interactions with the target amyloidogenic proteins have been expected to be involved for DQ to exhibit its defibrillation activity. The disintegrating activity of DQ was also evaluated in vivo with the yeast system overexpressing alpha-synuclein-GFP. With the DQ treatment, the intracellular green inclusions turned into green smears, which resulted in the enhanced cell death. Based on the data, the previous observation that DQ led to the predominant protofibril formation of alpha-synuclein could be explained by the dual function of DQ showing both the facilitated self-oligomerization of alpha-synuclein and the instantaneous defibrillation of its amyloid fibrils. In addition, amyloidosis-related cytotoxicity has been demonstrated to be amplified by the fragmentation of mature amyloid fibrils by DQ.

Dequalinium-induced cell death of yeast expressing alpha-synuclein-GFP fusion protein.

Intracellular toxic effects of the dequalinium-induced protofibrils of alpha-synuclein have been investigated with the yeast system expressing alpha-synuclein-GFP fusion protein in single copy, which appears in the green halo around the plasma membrane. Intracellular responses of the green fluorescent protein were analyzed as the cells were treated with dequalinium (DQ) and lactacystin. Yeast cells expressing alpha-synuclein-GFP were susceptible to both compounds in alpha-synuclein-dependent manner. Upon DQ treatment, the green halo became smeared throughout the cytoplasm while lactacystin induced a few discrete green dots, reflecting intracellular formation of the protofibrils and the protein inclusions, respectively. The DQ-treated yeast cells were intensely stained with the nucleic acid stains of cell-permeable Hoechst 33342 and cell-impermeable propidium imidione, indicating that nucleus has been disrupted in addition to plasma membrane destabilization. Those DQ-treated yeast cells, however, still contained active mitochondria identified with MitoTracker Red. Therefore, the DQ-induced protofibrillar state of alpha-synuclein-GFP has been suggested to cause the nuclear damage either independently or in combination with the membrane destabilization without affecting mitochondria.