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1.
Materials (Basel) ; 16(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36770083

RESUMO

Despite the improved conversion efficiency of Cu2(ZnSn)Se4 (CZTSe) solar cells, their roll-to-roll fabrication nonetheless leads to low performance. The selenization time and temperature are typically considered major parameters for a powder-based CZTSe film; meanwhile, the importance of the densification during the roll-to-roll process is often overlooked. The densification process is related to the porosity of the light-absorbing layer, where high porosity lowers cell performance. In this study, we fabricated a dense CZTSe absorber layer as a method of controlling the compression of a powder precursor (Cu1.7(Zn1.2Sn1.0)S4.0 (CZTS)) during the roll-press process. The increased particle packing density of the CZTS layer was crucial in sintering the powder layer into a dense film and preventing severe selenization of the Mo back electrode. The pressed absorber layer of the CZTSe solar cell exhibited a more uniform chemical composition determined using dynamic secondary ion mass spectrometry (SIMS). Under the AM 1.5G illumination condition, the power conversion efficiency of the pressed solar cell was 6.82%, while the unpressed one was 4.90%.

2.
Clin Hypertens ; 29(1): 4, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36721223

RESUMO

BACKGROUND: The relationship between stable isotope ratios and dietary protein sources has been reported. However, few studies have examined the effect of stable isotope ratios on metabolic risk in humans. We investigated whether the stable isotope ratios of carbon and nitrogen in human hair are associated with blood pressure and hypertension. METHODS: We conducted a cross-sectional study of 392 subjects (228 men and 164 women). Hair samples of the subjects were used for the measurement of stable isotope ratios of carbon (δ13C) and nitrogen (δ15N). RESULTS: The δ13C and δ15N values showed positive correlations with diastolic blood pressure in the subjects without antihypertensive medication. In the subjects without antihypertensive medication, the multivariable-adjusted odds ratio (95% confidence interval) for hypertension was 1.55 (1.04-2.30) per 1‰ increase in δ15N and 1.22 (0.86-1.73) per 1‰ increase in δ13C, respectively. However, in the subjects with antihypertensive medication, neither δ13C nor δ15N values showed a significant association with hypertension. CONCLUSIONS: The stable isotopic ratio of nitrogen in scalp hair is independently associated with hypertension in subjects without antihypertensive medication. The hair δ15N value might be used as a surrogate marker to screen a high-risk population for hypertension.

3.
Tohoku J Exp Med ; 243(2): 133-139, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29081462

RESUMO

Stable isotope ratios have been reported to be potential biomarkers of dietary intake and nutritional status. High serum levels of leptin, a hormone which regulates energy metabolism and food intake, are associated with insulin resistance and metabolic syndrome. However, little is known about the association between stable isotope ratios and the metabolic risk in humans. We investigated whether the carbon and nitrogen stable isotope ratios in hair are associated with serum leptin levels. Hair samples were collected from 399 healthy adults (233 men and 166 women) aged 40 to 70 years of a community-based cohort in Korea and the bulk stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) were measured for all hair samples. Serum leptin levels were analyzed by radioimmunoassay. δ15N showed positive correlations with serum leptin levels. In multivariate models, increasing δ15N were associated with elevated serum leptin levels (defined as ≥ the median values), whereas δ13C were not significantly associated with serum leptin levels. The odds ratio (95% confidence interval) per 1‰ increase in δ15N for an elevated serum leptin level was 1.58 (1.11-2.26). In participants with high body mass index, δ15N showed positive associations with serum leptin levels, whereas these associations were not seen in participants with low body mass index. The nitrogen stable isotopic ratio in hair is positively associated with serum leptin levels. The hair δ15N could be used as a clinical marker to estimate metabolic risk.


Assuntos
Cabelo/metabolismo , Marcação por Isótopo , Leptina/sangue , Isótopos de Nitrogênio/metabolismo , Antropometria , Índice de Massa Corporal , Isótopos de Carbono/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances
4.
Complement Ther Med ; 24: 40-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26860800

RESUMO

BACKGROUND: It has been observed that mitochondrial dysfunction is associated with an increased risk of metabolic syndrome. There is growing evidence that hyperactivity of the hypothalamus-pituitary-adrenal (HPA) axis and hormone (testosterone and growth hormone) deficiency may lead to metabolic syndrome. Recent studies have reported that ginseng treatment improves mitochondrial and HPA-axis function and increases anabolic hormone secretion. OBJECTIVES: The objective of this study was to investigate the effect of red ginseng (RG) on metabolic syndrome, hormones, and mitochondrial function using leukocyte mitochondrial DNA copy number in men with metabolic syndrome. METHODS: We performed a randomized, double-blind, placebo-controlled study in 62 subjects who were not taking drugs that could affect their metabolic function. A total of 62 men with metabolic syndrome were randomly assigned to either an RG group (3.0g/day) or a placebo group for 4 weeks. We analyzed changes in metabolic syndrome components, leukocyte mitochondrial DNA copy number, hormones (total testosterone, IGF-1, cortisol, and DHEAS) and inflammatory markers (C-reactive protein, ferritin) from baseline to 4 weeks. RESULTS: Significant improvement in mitochondrial function (95% CI -44.9 to -1.3) and an increase in total testosterone (95% CI -70.1 to -1.0) and IGF-1(P=0.01) levels were observed in the RG group when compared with the placebo group. Diastolic blood pressure (95% CI 2.0-9.4) and serum cortisol (95% CI 1.1-5.5) significantly decreased in the RG group. CONCLUSIONS: We found evidence that RG had a favorable effect on mitochondrial function and hormones in men with metabolic syndrome.


Assuntos
DNA Mitocondrial/efeitos dos fármacos , Dosagem de Genes/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Síndrome Metabólica/tratamento farmacológico , Panax/química , Extratos Vegetais/farmacologia , Adulto , Biomarcadores/sangue , Hormônios/sangue , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Projetos Piloto
5.
PLoS One ; 10(10): e0140360, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26469177

RESUMO

The objective of this study was to identify the association of blood lead level (BLL) with mortality in inorganic lead-exposed workers of South Korea. A cohort was compiled comprising 81,067 inorganic lead exposed workers working between January 1, 2000, and December 31, 2004. This cohort was merged with the Korean National Statistical Office to follow-up for mortality between 2000 and 2008. After adjusting for age and other carcinogenic metal exposure, all-cause mortality (Relative risk [RR] 1.36, 95% confidence interval [CI] 1.03-1.79), digestive disease (RR 3.23, 95% CI 1.33-7.86), and intentional self-harm (RR 2.92, 95% CI 1.07-7.81) were statistically significantly higher in males with BLL >20 µg/dl than of those with BLL ≤10µg/dl. The RR of males with BLL of 10-20 µg/dl was statistically higher than of those with BLL ≤10µg/dl in infection (RR 3.73. 95% CI, 1.06-13.06). The RRs of females with 10-20 µg/dl BLL was statistically significantly greater than those with BLL <10µg/dl in all-cause mortality (RR 1.93, 95% CI 1.16-3.20) and colon and rectal cancer (RR 13.42, 95% CI 1.21-149.4). The RRs of females with BLL 10-20 µg/dl (RR 10.45, 95% CI 1.74-62.93) and BLL ≥20 µg/dl (RR 12.68, 95% CI 1.69-147.86) was statistically significantly increased in bronchus and lung cancer. The increased suicide of males with ≥20 µg/dl BLLs, which might be caused by major depression, might be associated with higher lead exposure. Also, increased bronchus and lung cancer mortality in female workers with higher BLL might be related to lead exposure considering low smoking rate in females. The kinds of BLL-associated mortality differed by gender.


Assuntos
Neoplasias Gastrointestinais/epidemiologia , Intoxicação por Chumbo/mortalidade , Chumbo/sangue , Exposição Ocupacional/efeitos adversos , Neoplasias do Sistema Respiratório/epidemiologia , Adulto , Feminino , Humanos , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/epidemiologia , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/estatística & dados numéricos , Suicídio/estatística & dados numéricos
6.
Clin Chim Acta ; 450: 72-7, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26238186

RESUMO

BACKGROUND: It has been reported that stable isotope ratios can be used as biomarkers for animal protein intake. Meat consumption and high protein intake could be risk factors for metabolic disorders. We investigated whether the stable isotope ratios of carbon and nitrogen are associated with metabolic syndrome. METHODS: We conducted a cross-sectional study of 399 subjects (233 men and 166 women). Hair samples from 399 subjects were measured for stable isotope ratios of carbon (δ(13)C) and nitrogen (δ(15)N). RESULTS: The δ(15)N values progressively increased with the number of components of the metabolic syndrome present in study subjects (P for trend 0.047). In multivariable models, δ(15)N values were positively associated with the presence of metabolic syndrome (odds ratio, 1.53; 95% confidence interval, 1.09-2.14), whereas δ(13)C values were not (odds ratio, 0.97; 95% confidence interval, 0.72-1.30). The odds ratio (95% confidence interval) for metabolic syndrome comparing the highest to the lowest quartiles of δ(15)N values was 2.64 (1.17-5.92). CONCLUSIONS: The nitrogen, but not carbon, stable isotopic ratio of hair is independently associated with the presence of metabolic syndrome. The hair δ(15)N value might be a surrogate marker for clustering of risk factors in metabolic syndrome.


Assuntos
Isótopos de Carbono/análise , Cabelo/química , Síndrome Metabólica/metabolismo , Isótopos de Nitrogênio/análise , Adulto , Idoso , Biomarcadores/análise , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia
7.
J Korean Med Sci ; 30(4): 407-13, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25829808

RESUMO

The utility of electrocardiography (ECG) in screening for left ventricular hypertrophy (LVH) in general populations is limited mainly because its low sensitivity. B-type natriuretic peptide (BNP) is released due to the remodeling processes of LVH and could improve the diagnostic accuracy for the ECG criteria for LVH. We hypothesized that addition of BNP levels to ECG criteria could aid LVH detection compared with ECG alone in a general population. We enrolled consecutive 343 subjects from a community-based cohort. LVH was defined as LV mass index > 95 g/m(2) for females and > 115 g/m(2) for males according to echocardiography. The area under the receiver operator characteristic (ROC) curve to detect LVH was 0.55 (95% confidence interval [CI], 0.50-0.61) in Sokolow-Lyon criteria and 0.53 (0.47-0.59) in the Cornell voltage criteria. After addition of N-terminal-proBNP levels to the model, the corresponding areas under the ROC were 0.63 (0.58-0.69) and 0.64 (0.59-0.69), respectively. P values for the comparison in areas under the ROC for models with and without N-terminal-proBNP levels were < 0.001. These data suggest that addition of N-terminal-proBNP levels to ECG criteria could significantly improve the diagnostic accuracy of LVH in general populations.


Assuntos
Eletrocardiografia , Hipertrofia Ventricular Esquerda/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Adulto , Estudos de Coortes , Feminino , Humanos , Hipertrofia Ventricular Esquerda/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC
8.
PLoS One ; 10(3): e0119731, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25806957

RESUMO

BACKGROUND: This study aimed to assess the association between oxidative damage markers and carotid artery intima-media thickness (CIMT) after controlling for conventional risk factors of atherosclerosis in multiple logistic regression models. METHODS AND FINDINGS: Fifty-one case male participants (CIMT ≥ 0.9 mm) were enrolled during their visits to Korean Genomic Rural Cohort Study of Wonju centers between May 1 and August 31, 2011, along with 51 control participants (CIMT < 0.9 mm) selected using frequency matching by age group. The levels of oxidative damage markers, 8-hydroxy-2'-deoxyquuanosine (8-OHdG), malondialdehyde (MDA), and 8-iso-prostaglandin F2α (Isoprostane), were measured. Conditional logistic regression models were used to evaluate relative relationships between the oxidative damage markers and the risk of high CIMT. RESULTS: The markers of oxidative lipid (Isoprostane and MDA) and DNA (8-OHdG) damage were associated with CIMT after controlling for the conventional risk factors, including age, low density lipoprotein, body mass index, smoking history, alcohol consumption, and metabolic syndrome (ORs [95% CI] for Isoprostane: 3rd tertile, 8.47 [2.59-27.67]; for MDA: 3rd tertile, 8.47 [2.59-27.67]; for 8-OHdG: 3rd tertile, 5.58 [1.79-17.33]). When all the oxidative damage markers were incorporated in the same logistic regression model, only Isoprostane was significantly related to CIMT (OR [95% CI]: 4.22 [1.31-13.53] in 2nd tertile and 14.21 [3.34-60.56] in 3rd tertile). CONCLUSIONS: In this nested case-control study, the oxidative damage markers of lipid and DNA were associated with CIMT even after controlling for the conventional risk factors of cardiovascular diseases.


Assuntos
Aterosclerose/etiologia , Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/etiologia , Estresse Oxidativo/fisiologia , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/diagnóstico por imagem , Aterosclerose/metabolismo , Biomarcadores/sangue , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/metabolismo , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Estudos de Coortes , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Humanos , Isoprostanos/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Fatores de Risco
9.
Nanoscale ; 6(20): 11703-11, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25091974

RESUMO

Efficient Cu2ZnSnSe4 (CZTSe) solar cells were fabricated with a simple, environmentally friendly, and scalable synthetic method for Cu2ZnSnS4 (CZTS) nanocrystals. CZTS nanoparticles were mechanochemically synthesized from elemental precursors on a relatively large scale (∼20 g), during which no solvents or additives were used, thus alleviating the complex process of particle synthesis. An analysis of the time evolution of the crystalline phase and morphology of precursor powders revealed that the formation of the CZTS compound was completed in 0.5 h once initiated, suggesting that the mechanochemically induced self-propagating reaction prevails. CZTS ink was prepared by dispersing the as-synthesized nanoparticles in an environmentally benign solvent (160 mg mL(-1) in ethanol) without using any additives, after which it was cast onto Mo-coated glass substrates by a doctor-blade method. Subsequent reactive annealing at 560 °C under a Se-containing atmosphere resulted in substantial grain growth along with the nearly complete substitution of Se. The CZTSe solar cells therefrom exhibited power conversion efficiency levels as high as 6.1% (based on the active area, 0.44 cm(2)) with a relatively high open-circuit voltage (0.42 V) in comparison with the bandgap energy of 1.0 eV.

10.
BMJ Open ; 4(5): e005025, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24848088

RESUMO

OBJECTIVE: The objectives of this study were to develop a coronary heart disease (CHD) risk model among the Korean Heart Study (KHS) population and compare it with the Framingham CHD risk score. DESIGN: A prospective cohort study within a national insurance system. SETTING: 18 health promotion centres nationwide between 1996 and 2001 in Korea. PARTICIPANTS: 268 315 Koreans between the ages of 30 and 74 years without CHD at baseline. OUTCOME MEASURE: Non-fatal or fatal CHD events between 1997 and 2011. During an 11.6-year median follow-up, 2596 CHD events (1903 non-fatal and 693 fatal) occurred in the cohort. The optimal CHD model was created by adding high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides to the basic CHD model, evaluating using the area under the receiver operating characteristic curve (ROC) and continuous net reclassification index (NRI). RESULTS: The optimal CHD models for men and women included HDL-cholesterol (NRI=0.284) and triglycerides (NRI=0.207) from the basic CHD model, respectively. The discrimination using the CHD model in the Korean cohort was high: the areas under ROC were 0.764 (95% CI 0.752 to 0.774) for men and 0.815 (95% CI 0.795 to 0.835) for women. The Framingham risk function predicted 3-6 times as many CHD events than observed. Recalibration of the Framingham function using the mean values of risk factors and mean CHD incidence rates of the KHS cohort substantially improved the performance of the Framingham functions in the KHS cohort. CONCLUSIONS: The present study provides the first evidence that the Framingham risk function overestimates the risk of CHD in the Korean population where CHD incidence is low. The Korean CHD risk model is well-calculated alternations which can be used to predict an individual's risk of CHD and provides a useful guide to identify the groups at high risk for CHD among Koreans.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Prognóstico , Estudos Prospectivos , República da Coreia , Medição de Risco
11.
Diabetes Res Clin Pract ; 103(1): 51-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24398319

RESUMO

AIMS: The aim of this study was to investigate the association between serum adiponectin level and new-onset hypertension, and the relative contribution of obesity and low serum adiponectin levels to the development of hypertension in normotensive men and women. METHODS: We analyzed 1553 adults (584 men and 969 women) without hypertension, aged 40-70 years, who had participated in a cohort study in both time periods from 2005 to 2008 for baseline and 2008 to 2011 for follow-up. We divided participants into sex-specific tertiles according to serum adiponectin levels. We defined the highest tertile of serum adiponectin as 'high adiponectin'. Participants were then stratified into four groups: the non-obese with high adiponectin; the non-obese with low adiponectin; the obese with high adiponectin; and the obese with low adiponectin. RESULTS: During an average of 2.6 years of follow-up, 79 men (13.5%) and 99 women (10.2%) developed hypertension. Low serum adiponectin level was an independent predictor of new-onset hypertension in men (Odds Ratio[OR]: 1.99; 95% CI: 1.03-3.86). The Obese men with low adiponectin had an increased risk of new-onset hypertension compared with the control group (OR: 2.80; 95% CI: 1.35-5.81). In postmenopausal women, the obese subjects with low adiponectin had an increased risk of new-onset hypertension compared with the control group (OR: 2.41; 95% CI 1.16-5.04). CONCLUSION: Low serum adiponectin levels were associated with an increased risk of new-onset hypertension in men and postmenopausal women.


Assuntos
Adiponectina/sangue , Biomarcadores/sangue , Hipertensão/etiologia , Obesidade/complicações , Adulto , Idoso , Pressão Sanguínea , Feminino , Seguimentos , Humanos , Hipertensão/sangue , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Prognóstico , Estudos Prospectivos
12.
Eur J Prev Cardiol ; 21(12): 1484-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23864362

RESUMO

BACKGROUND: To describe the rationale, objectives, protocol, and preliminary results for a new prospective cohort study of cardiovascular disease (CVD) risk factors in South Korea. METHODS: Study members were recruited from participants in routine health assessments at health promotion centres across South Korea. Established and emerging CVD risk factors were measured. Eighteen centres holding electronic health records agreed to linkage of participants' records to future health insurance claims for monitoring of disease events. The recruitment of 430,920 participants (266,782 men, 164,138 women), aged 30-74 years, provides broad geographical reach across South Korea. RESULTS: Risk factor prevalence was more favourable in women than men, and, in general, in the younger rather than older study members. There was also close similarity between the characteristics of the present sample and the Korean National Health and Nutrition Examination Survey. The expected associations between risk factors and both CVD and death were also apparent. CONCLUSIONS: Data from the present sample, based on data linkage, show close agreement with South Korea-wide surveys (for risk factor prevalence) and the extant literature (for risk factor associations). These findings gives confidence in future results anticipated from this cohort study of east Asians - a group that has been traditionally under-researched.


Assuntos
Povo Asiático , Cardiopatias/etnologia , Projetos de Pesquisa , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Registros Eletrônicos de Saúde , Feminino , Inquéritos Epidemiológicos , Cardiopatias/diagnóstico , Cardiopatias/mortalidade , Humanos , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Fatores de Risco , Distribuição por Sexo , Fatores Sexuais , Fatores de Tempo
13.
J Korean Med Sci ; 28(12): 1762-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24339706

RESUMO

Increased epicardial adipose tissue (EAT) may be closely associated with the development of metabolic abnormalities. We investigated whether EAT predicts the incident metabolic syndrome in a community-based, middle-aged population. The study subjects were comprised of 354 adults (134 men and 220 women) aged 40 to 70 yr without metabolic syndrome. Baseline EAT thickness, measured by echocardiography, was compared between subjects who developed new-onset metabolic syndrome at follow-up survey and those who did not. After an average of 2.2 yr of follow-up, 32 men (23.9%) and 37 women (16.8%) developed metabolic syndrome. Median EAT thickness at baseline was significantly higher in male subjects who developed metabolic syndrome than those who did not (1.52 mm vs 2.37 mm, P<0.001). The highest quartile of EAT thickness (≥2.55 mm) was associated with increased risk of progression to metabolic syndrome (Odds ratio [OR], 3.09; 95% confidence interval [CI], 1.11-8.66) after adjustment for age, smoking, alcohol intake, regular exercise, total energy intake, high sensitive C-reactive protein and homeostasis model assessment of insulin resistance in men. A significant association of EAT with incident metabolic syndrome was not seen in women (OR, 1.25; 95% CI, 0.54-2.90). In conclusion, increased EAT thickness is an independent predictor for incident metabolic syndrome in men.


Assuntos
Tecido Adiposo/fisiopatologia , Síndrome Metabólica/epidemiologia , Pericárdio/patologia , Adulto , Idoso , Pressão Sanguínea , Índice de Massa Corporal , Proteína C-Reativa/análise , Ecocardiografia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pericárdio/fisiopatologia , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Circunferência da Cintura
14.
J Nanosci Nanotechnol ; 13(9): 6042-51, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24205596

RESUMO

Cu(In,Ga)Se2 (CIGS) is a compound semiconductor and is one of the most attractive light-absorbing materials for use in thin film solar cells. Among the various approaches to prepare CIGS thin films, the powder process offers an extremely simple and materials-efficient method. Here, we report the mechano-chemical preparation of CIGS compound powders suitable for fabrication of CIGS films by a powder process. We found that the CIGS phase was formed from the elemental powders of Cu, In, and Se and liquid Ga using high energy milling process with a milling time as short as 40 min at 200 rpm due to a self-accelerating exothermic reaction. The morphology and size of the CIGS powders changed with a function of the milling speed (100-300 rpm), leading to an optimal condition of milling at 200 rpm for 120 min. We also found that it was difficult to obtain a monolithic phase of the CIGS powders without severe particle aggregation by mechano-chemical milling alone. Therefore, in combination with the milling, subsequent heat-treatment at 300 degrees C was performed, which successfully provided monolithic CIGS nanopowders suitable for powder process. When a thin film was fabricated from the monolithic CIGS nanopowders, a highly dense film with large crystalline grains was obtained. The CIGS film preserved its chemical composition of CuIn0.7Ga0.3Se2 after sintering as evidenced by Raman spectroscopy, EDS and SAED pattern of transmission electron microscopy. The film was also found suitable for a light absorbing layer of CIGS solar cells with its band gap energy of 1.14 eV evaluated by transmittance spectroscopy.

15.
Diabetes Care ; 36(6): 1547-53, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23275369

RESUMO

OBJECTIVE: Increased adiponectin levels may play a protective role in the development of metabolic abnormalities, but prospective studies of the predictive value of serum adiponectin to identify individuals at high risk of new-onset metabolic syndrome are lacking. We investigated whether serum adiponectin predicts incident cases of the metabolic syndrome in a population-based longitudinal study. RESEARCH DESIGN AND METHODS: A prospective cohort study was conducted of 2,044 adults (831 men and 1,213 women) aged 40-70 years without metabolic syndrome examined in 2005-2008 (baseline) and 2008-2011 (follow-up). Baseline serum adiponectin concentrations were measured by radioimmunoassay. RESULTS: During an average of 2.6 years of follow-up, 153 men (18.4%) and 199 women (16.4%) developed metabolic syndrome. In multivariable-adjusted models, the odds ratio for incident metabolic syndrome comparing the highest with the lowest quartiles of adiponectin levels was 0.25 (95% CI 0.14-0.47) in men and 0.45 (0.28-0.74) in women. While serum adiponectin did not improve the area under the ROC curve for predicting new-onset metabolic syndrome based on information from metabolic syndrome components, the net reclassification improvement and the integrated discrimination improvement of prediction models including adiponectin were significantly higher compared with those of models not including adiponectin among men, with a significant difference between men and women (P = 0.001). CONCLUSIONS: Increased adiponectin is an independent protective factor for incident metabolic syndrome in men and women, and it may have a clinical role in predicting new-onset metabolic syndrome among men.


Assuntos
Adiponectina/sangue , Síndrome Metabólica/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Fatores de Risco
16.
Tohoku J Exp Med ; 225(3): 187-93, 2011 11.
Artigo em Inglês | MEDLINE | ID: mdl-22001675

RESUMO

Chronic sleep deprivation is increasingly common in industrialized societies. Short sleep duration has been associated with a number of negative health outcomes. The objectives of this study were to investigate the association between self-reported sleep duration and the presence of metabolic syndrome (combination of central obesity, triglyceride, high density lipoprotein, blood pressure, fasting plasma glucose) in adults during midlife. The Korean Genomic Rural Cohort (KGRC) is a cohort study of aged 40 to 70 years in rural Korea. This study focuses on the prevalence, incidence, and risk factors for chronic degenerative disorders, such as hypertension, diabetes, osteoporosis, respiratory diseases, and metabolic syndrome. The baseline sample of participants in the KGRC study was recruited in 2005-2006 (phase 1). Respondents were followed until 2008-2009 (phase 2). The final sample included 1,107 subjects: 386 males (34.9%) and 721 females (65.1%). The incidence rate of metabolic syndrome in our sample was 18.4% (21.2% for males and 16.9% for females). Subjects sleeping < 6 hours a day (HR: 1.798; 95% CI: 1.06-3.05) were significantly more likely to experience metabolic syndrome than participants sleeping 6 to 7.9 hours a day after controlling for potential covariates (age, body mass index, menopause, smoking, alcohol and physical activity). Shorter sleep duration was associated with the high incidence of metabolic syndrome among females only. In conclusion, shorter sleep duration may be a significant risk factor for the development of metabolic syndrome in women.


Assuntos
Síndrome Metabólica/epidemiologia , Síndrome Metabólica/fisiopatologia , Sono/fisiologia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Fatores de Tempo
17.
Clin Chim Acta ; 412(23-24): 2199-205, 2011 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-21855536

RESUMO

BACKGROUND: Leptin and adiponectin are adipokines, shown to have opposing functions for fat metabolism and development of metabolic syndrome. We determined if the ratio of serum leptin to adiponectin (L/A ratio) adjunctively contributes to the risk of metabolic syndrome beyond the homeostasis model assessment of insulin resistance (HOMA-IR). METHODS: This study included 1532 men and 1856 women, aged 40-70 y assessed in the Korean Genomic Rural Cohort Study from 2005 to 2008. The serum concentrations of adiponectin and leptin were measured by radioimmunoassay. Area under the receiver operating characteristic curve (AUROC) analyses were used to describe the ability of L/A ratio and HOMA-IR to differentiate between subjects with and without metabolic syndrome. RESULTS: There were no significant differences in the ability of L/A ratio and HOMA-IR to predict metabolic syndrome (AUROC of L/A ratio vs. HOMA-IR, 0.771 vs. 0.774, p=0.8006 for men; 0.677 vs. 0.691, p=0.3088 for women). There was a significant adjunctive contribution by the L/A ratio, beyond that of HOMA-IR, to the risk of metabolic syndrome in men (p<0.0001 with 0.028 increased AUROC) and women (p=0.025 with 0.017 increased AUROC). CONCLUSIONS: The L/A ratio provides significant adjunctive information to the risk of metabolic syndrome beyond HOMA-IR alone. The L/A ratio could be a good surrogate marker to assess metabolic syndrome.


Assuntos
Adiponectina/sangue , Resistência à Insulina , Leptina/sangue , Síndrome Metabólica/sangue , Adulto , Idoso , Feminino , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia
18.
Ann Hum Biol ; 38(5): 640-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21745154

RESUMO

BACKGROUND AND AIMS: Metabolic syndrome (MetS) is considered to be an insulin-resistance syndrome, but recent evidence suggests that MetS has multiple physiological origins which may be related to atherosclerosis. This study investigated clustering patterns of metabolic risk factors and its association with sub-clinical atherosclerosis. SUBJECTS AND METHODS: This study used factor analysis of 11 metabolic factors in 1374 individuals to define clustering patterns and determine their association with carotid intima-media thickness (CIMT). Eleven metabolic factors were used: body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), fasting blood insulin (FBI), serum triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), homeostasis model assessment-insulin resistance (HOMA-IR), high-sensitivity C-reactive protein (hsCRP) and adiponectin. Two regression analyses were done, the first using individual metabolic variables and the second using each factor from the factor analysis to evaluate their relationships with CIMT. RESULTS: Four clustering patterns, insulin-resistance factor (FBG, FBI, HOMA-IR), obesity-inflammatory factor (BMI, WC, hsCRP), blood pressure factor (SBP, DBP) and lipid metabolic factor (HDL-C, TG, adiponectin) were categorized. In a multivariate regression model after adjustment for age, sex, low-density lipoprotein cholesterol and smoking history (pack year), insulin resistance factor (B = 11.09, p = 0.026), obesity-inflammatory factor (B = 18.50, p < 0.001), blood pressure factor (B = 12.84, p = 0.010) and lipid metabolic factor (B = - 11.55, p = 0.023) were found to be significantly associated with CIMT. CONCLUSION: In conclusion, metabolic risk factors have four distinct clustering patterns that are independently associated with sub-clinical atherosclerosis.


Assuntos
Povo Asiático , Aterosclerose/complicações , Aterosclerose/epidemiologia , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Análise por Conglomerados , Estudos de Coortes , Análise Fatorial , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , República da Coreia/epidemiologia , Fatores de Risco , Túnica Íntima/patologia , Túnica Média/patologia
19.
J Korean Med Sci ; 26(3): 365-71, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21394304

RESUMO

Carotid intima-media thickness (CIMT) is considered as a surrogate marker for cardiovascular disease (CVD). We determined the normative value of CIMT and correlates of CVD risk factors and Framingham risk score (FRS) in Korean rural middle-aged population. We measured CIMT with a B-mode ultrasonography in 1,759 subjects, aged 40 to 70 yr, in a population-based cohort in Korea. A healthy reference sample (n = 433) without CVD, normal weight and normal metabolic parameters was selected to establish normative CIMT values. Correlates between CIMT and conventional CVD risk factors were assessed in the entire population. Mean values of CIMT (in mm) for healthy reference sample aged 40-49, 50-59, and 60-70 yr were 0.55, 0.59, and 0.66 for men and 0.48, 0.55, and 0.63 for women, respectively. In multivariate regression analysis, CIMT was correlated with older age, higher BMI, male gender, higher LDL-cholesterol level and history of diabetes mellitus. The mean CIMT was also correlated with FRS in both gender (r(2) = 0.043, P < 0.01 for men; r(2) = 0.142, P < 0.01 for women). We identified normative value of CIMT for the healthy Korean rural middle-aged population. The CIMT is associated with age, obesity, gender, LDL-cholesterol, diabetes mellitus and FRS.


Assuntos
Aterosclerose/diagnóstico por imagem , Doenças Cardiovasculares/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Adulto , Idoso , Aterosclerose/epidemiologia , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , LDL-Colesterol/sangue , Estudos Transversais , Diabetes Mellitus , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , República da Coreia , Fatores de Risco , Saúde da População Rural , Ultrassonografia
20.
Yonsei Med J ; 52(2): 234-41, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21319340

RESUMO

PURPOSE: Growing evidence suggests that hypoadiponectinemia may play a significant role in the development of metabolic syndrome (MetS). Therefore, the relationships between serum adiponectin with MetS and components of MetS were investigated in non-diabetic samples of drawn from the Koreans general population. MATERIALS AND METHODS: We performed a cross-sectional study in samples of older Koreans (age > 40 years) including 2,471 men and 3,463 women. MetS was defined according to the Asian modified criteria of the National Cholesterol Education Program Adult Treatment Panel III report. Serum adiponectin concentrations were measured by radioimmunoassay. RESULTS: The median adiponectin level in MetS was significantly lower than that in non-MetS subjects in men (6.00 vs. 8.00 µg/mL, p < 0.001) and women (10.12 vs. 11.74 µg/mL, p < 0.001). Adiponectin concentration was negatively correlated with waist circumference and levels of triglyceride, C-reactive protein (CRP), fasting glucose, and insulin, and positively correlated with high-density lipoprotein and age in both genders (p < 0.001). In a multivariate regression model after adjustment for age, body mass index, smoking, CRP, and lipid profiles, the odds ratio of MetS comparing extreme quartiles of adiponectin distribution was 0.32 [95% confidence interval (CI), 0.20 to 0.50] in men and 0.57 (95% CI, 0.43 to 0.76) in women. CONCLUSION: Adiponectin levels are independently associated with the phenotype of MetS, as well as components of MetS in the non-diabetic Korean general population.


Assuntos
Adiponectina/sangue , Síndrome Metabólica/sangue , Adiponectina/fisiologia , Glicemia/análise , Índice de Massa Corporal , Proteína C-Reativa/análise , Estudos Transversais , Feminino , Humanos , Insulina/sangue , Lipoproteínas HDL/sangue , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , República da Coreia , Razão de Masculinidade , Triglicerídeos/sangue , Circunferência da Cintura/fisiologia
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