Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 115
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Biochem Biophys Res Commun ; 723: 150187, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-38850809

RESUMO

This study investigated the effects of far-infrared (FIR) irradiation on low-density lipoprotein cholesterol (LDL-C) uptake by human hepatocellular carcinoma G2 (HepG2) cells via the regulation of proprotein convertase subtilisin/kexin type 9 (PCSK9). FIR irradiation for 30 min significantly decreased PCSK9 expression (p < 0.01) in HepG2 cells. FIR irradiation substantially increased the low-density lipoprotein receptor (p < 0.0001) and LDL-C uptake (p < 0.01). Activation of transient receptor potential vanilloid (TRPV) channels mimicked the effects of FIR irradiation, significantly decreasing the protein expression of PCSK9 (p < 0.05). Conversely, inhibition of TRP channels using ruthenium red reversed the reduction in PCSK9 protein expression following FIR irradiation (p < 0.01). The specific activation of TRPV4 using 4α-PDD mimicked the effect of FIR irradiation (p < 0.01), whereas PCSK9 reduction by FIR irradiation was significantly reversed by the inhibition of TRPV4 using RN1734 (p < 0.05). These findings implied that FIR irradiation emitted from a ceramic lamp specifically increased TRPV4 activity. These findings provide insights into a novel therapeutic approach using FIR irradiation for LDL-C regulation and its implications for cardiovascular health.


Assuntos
LDL-Colesterol , Regulação para Baixo , Raios Infravermelhos , Pró-Proteína Convertase 9 , Canais de Cátion TRPV , Humanos , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertase 9/genética , Células Hep G2 , Canais de Cátion TRPV/metabolismo , LDL-Colesterol/metabolismo , Regulação para Baixo/efeitos da radiação
2.
Int J Mol Sci ; 24(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36768379

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disease and the blood-brain barrier dysfunction has been suggested as a key pathological feature of the disease. Our research group successfully established a synthetic protocol for oleracones, a novel series of flavonoids isolated from the plant extract of Portulaca oleracea L. (PO). PO extract was reported to have anti-inflammatory and antioxidant effects, enhancing cognitive function. Thus, we investigated the effects and mechanism of oleracones on cognition using AD model transgenic mice (Tg; APPswe/PSEN1dE9). Oleracone F treatment significantly improved memory dysfunction in Tg mice. Oleracone F decreased the number, burden, and immunoreactivity of amyloid plaques and amyloid precursor protein (APP) protein levels in the brains of Tg mice compared to wild-type mice. Oleracone F also alleviated inflammation observed in Tg mice brains. In vitro studies in human microvascular endothelial cells (HBMVECs) demonstrated that oleracones D, E, and F blocked the elevations in VCAM-1 protein induced by tumor necrosis factor-α (TNF-α), hindering leukocyte adhesion to HBMVECs. Taken together, our results suggest that oleracones ameliorated cognitive impairment by blocking TNF-α-induced increases in VCAM-1, thereby reducing leukocyte infiltration to the brain and modulating brain inflammation.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Camundongos , Humanos , Animais , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células Endoteliais/metabolismo , Doenças Neurodegenerativas/metabolismo , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Camundongos Transgênicos , Disfunção Cognitiva/metabolismo , Peptídeos beta-Amiloides/metabolismo
3.
Int J Mol Sci ; 23(2)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35054901

RESUMO

Mesenchymal stem cells (MSCs) can differentiate into endoderm lineages, especially parathyroid-hormone (PTH)-releasing cells. We have previously reported that tonsil-derived MSC (T-MSC) can differentiate into PTH-releasing cells (T-MSC-PTHCs), which restored the parathyroid functions in parathyroidectomy (PTX) rats. In this study, we demonstrate quality optimization by standardizing the differentiation rate for a better clinical application of T-MSC-PTHCs to overcome donor-dependent variation of T-MSCs. Quantitation results of PTH mRNA copy number in the differentiated cells and the PTH concentration in the conditioned medium confirmed that the differentiation efficiency largely varied depending on the cells from each donor. In addition, the differentiation rate of the cells from all the donors greatly improved when differentiation was started at a high cell density (100% confluence). The large-scale expression profiling of T-MSC-PTHCs by RNA sequencing indicated that those genes involved in exiting the differentiation and the cell cycle were the major pathways for the differentiation of T-MSC-PTHCs. Furthermore, the implantation of the T-MSC-PTHCs, which were differentiated at a high cell density embedded in hyaluronic acid, resulted in a higher serum PTH in the PTX model. This standardized efficiency of differentiation into PTHC was achieved by initiating differentiation at a high cell density. Our findings provide a potential solution to overcome the limitations due to donor-dependent variation by establishing a standardized differentiation protocol for the clinical application of T-MSC therapy in treating hypoparathyroidism.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Tonsila Palatina/citologia , Hormônio Paratireóideo/biossíntese , Biomarcadores , Cálcio/metabolismo , Técnicas de Cultura de Células , Células Cultivadas , Inibição de Contato , Espaço Extracelular/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células-Tronco Mesenquimais/citologia
4.
Stem Cells ; 37(10): 1252-1260, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31287931

RESUMO

Since the discovery of stem cells and multipotency characteristics of mesenchymal stem cells (MSCs), there has been tremendous development in regenerative medicine. MSCs derived from bone marrow have been widely used in various research applications, yet there are limitations such as invasiveness of obtaining samples, low yield and proliferation rate, and questions regarding their practicality in clinical applications. Some have suggested that MSCs from other sources, specifically those derived from palatine tonsil tissues, that is, tonsil-derived MSCs (TMSCs), could be considered as a new potential therapeutic tool in regenerative medicine due to their superior proliferation rate and differentiation capabilities with low immunogenicity and ease of obtaining. Several studies have determined that TMSCs have differentiation potential not only into the mesodermal lineage but also into the endodermal as well as ectodermal lineages, expanding their potential usage and placing them as an appealing option to consider for future studies in regenerative medicine. In this review, the differentiation capacities of TMSCs and their therapeutic competencies from past studies are addressed. Stem Cells 2019;37:1252-1260.


Assuntos
Células-Tronco Mesenquimais/metabolismo , Tonsila Palatina/metabolismo , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos , Humanos , Tonsila Palatina/citologia
5.
Cell Physiol Biochem ; 52(2): 240-253, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30816672

RESUMO

BACKGROUND/AIMS: Far-infrared (FIR) irradiation has been reported to exhibit various biological effects including improvement of cardiovascular function. However, its effect on the differentiation of stem cells has not been studied. Using tonsil-derived mesenchymal stem cells (TMSC), we examined whether and how FIR irradiation affects adipogenic or osteogenic differentiation. METHODS: TMSC were exposed to FIR irradiation (3-25 µm wavelength) for various times (0, 30, or 60 min), and then adipogenic or osteogenic differentiation was induced for 14 days with its respective commercially available differentiation medium. At the end of the differentiation, the cells were stained using Oil red O or Alizarin red S solution, and the expression of differentiation-specific proteins was analyzed by western blotting. RESULTS: FIR irradiation did not alter cell viability or the expression of MSC-specific surface antigens (CD14, CD34, CD45, CD73, CD90, and CD105) in TMSC. However, FIR irradiation significantly inhibited adipogenic differentiation of TMSC, as evidenced by decreased Oil red O staining as well as protein expression of peroxisome proliferator-activated receptor γ and fatty acid binding protein 4. In contrast, FIR irradiation induced osteogenic differentiation, as evidenced by increased Alizarin red S staining as well as protein expression of osteocalcin and alkaline phosphatase. Treatment with heat alone did not inhibit the adipogenic differentiation of TMSC, suggesting that the inhibitory effect on adipogenic differentiation was not due to heat induced by FIR irradiation. However, heat alone did stimulate osteogenic differentiation, but to a lesser extent than FIR irradiation. Furthermore, FIR irradiation increased intracellular Ca²âº levels and the activity of protein phosphatase 2B (PP2B) in TMSC. Treatment with cyclosporin A, a specific PP2B inhibitor, reversed the inhibitory effect of FIR irradiation on adipogenic differentiation of TMSC, but had no effect on osteogenic differentiation. CONCLUSION: Our data demonstrate that FIR irradiation inhibits adipogenic differentiation but enhances osteogenic differentiation of TMSC; the inhibitory effect on adipogenic differentiation is non-thermal and mediated at least in part by activation of Ca²âº-dependent PP2B.


Assuntos
Adipogenia , Calcineurina/metabolismo , Diferenciação Celular , Raios Infravermelhos , Células-Tronco Mesenquimais/enzimologia , Osteogênese , Tonsila Palatina/enzimologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Células-Tronco Mesenquimais/citologia , Tonsila Palatina/citologia
6.
J Nanosci Nanotechnol ; 19(8): 4691-4694, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30913770

RESUMO

In this work, a Zr-doped TiOx layer is introduced into p-i-n planar-structure perovskite solar cells via a simple sol-gel method. The prepared device configuration is ITO/PEDOT:PSS/CH3NH3PbIxCl3-x/PC60BM/Zr-TiOx/Al. The performance of the perovskite solar cells was investigated through measurements of the current-voltage characteristics, impedance analysis, and photocurrent decay. A power conversion efficiency of 15.43% was measured under 1 sun condition; this level of efficiency is 27% higher than that of the device with a Zr-free TiOx layer. Additionally, the incorporation of Zr into the TiOx layer improved the carrier extraction as a result of the oxygen vacancy trap passivation. Lastly, the trap passivation of the Zr-TiOx film was confirmed by analyzing the photoluminescence spectrum.

7.
Environ Res ; 161: 195-201, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29156342

RESUMO

BACKGROUND: Bisphenol A (BPA) is an endocrine disrupter that acts in an estrogen-like manner. Few studies have investigated the association between urinary BPA concentrations and adverse liver function. Additionally, most studies were cross-sectional in nature and included only adults. OBJECTIVES: We evaluated BPA exposure levels and prospectively explored the association between BPA exposure and liver function in children. METHODS: Data were retrieved from the ongoing prospective Ewha Birth and Growth Cohort Study. Urinary BPA concentrations were measured in 164 children at 3-5 and 7-9 years of age. At each visit, fasting blood and urine samples were collected, and questionnaires were completed. The associations between the BPA concentrations at these ages and the serum levels of liver enzymes measured at 10-13 years of age were analyzed (n = 113). Multiple regression analysis was performed with adjustment for covariates. We also explored whether the BPA level exhibited dose-response relationships with liver enzyme levels. RESULTS: The median urinary BPA concentrations were 0.76µg/g creatinine at 3-5 years and 0.61µg/g creatinine at 7-9 years of age. The urinary BPA concentrations at the two ages were correlated significantly (r = 0.23, p < 0.01). The urinary BPA concentrations at 7-9 years, but not that at 3-5 years, was associated significantly with the serum levels of liver enzymes at 10-13 years of age (p < 0.05). Those in the top tertile of urinary BPA concentration had higher levels of liver enzymes than did others. After adjustment for covariates, dose-response relationships of the BPA level with liver enzyme levels were evident at 7-9 years, but not at 3-5 years. Notably, the effect size was larger and the dose-response relationships were more evident in boys than in girls. CONCLUSIONS: Exposure of children to even low doses of BPA may adversely affect later liver function.


Assuntos
Compostos Benzidrílicos , Fígado , Fenóis , Adolescente , Adulto , Idoso , Compostos Benzidrílicos/efeitos adversos , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Fenóis/efeitos adversos , Estudos Prospectivos , Adulto Jovem
8.
Toxicol Appl Pharmacol ; 318: 33-40, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28130037

RESUMO

Penicillium mycotoxins (PMs) are toxic contaminants commonly found as mixtures in animal feed. Therefore, it is important to investigate potential joint toxicity of PM mixtures. In the present study, we assessed the joint effect of binary combinations of the following PMs: citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA) and penicillic acid (PA) using independent action (IA) and concentration addition (CA) concepts. Previously published toxicity data (i.e. IC25; PM concentration that inhibited bovine macrophage (BoMacs) proliferation by 25%) were initially analyzed, and both concepts agreed that OTA+PA demonstrated synergism (p<0.05), while PAT+PA showed antagonism (p<0.05). When a follow-up dilution study was carried out using binary combinations of PMs at three different dilution levels (i.e. IC25, 0.5∗IC25, 0.25∗IC25), only the mixture of CIT+OTA at 0.5∗IC25 was determined to have synergism by both IA and CA concepts with Model Deviation Ratios (MDRs; the ratio of predicted versus observed effect concentrations) of 1.4 and 1.7, respectively. The joint effect of OTA+MPA, OTA+PA and CIT+PAT complied with the IA concept, while CIT+PA, PAT+MPA and PAT+PA were better predicted with the CA over the IA concept. The present study suggests to test both IA and CA concepts using multiple doses when assessing risk of mycotoxin mixtures if the mode of action is unknown. In addition, the study showed that the tested PMs could be predicted by IA or CA within an approximate two-fold certainty, raising the possibility for a joint risk assessment of mycotoxins in food and feed.


Assuntos
Antibacterianos/metabolismo , Citrinina/metabolismo , Macrófagos/metabolismo , Micotoxinas/metabolismo , Ocratoxinas/metabolismo , Penicillium/metabolismo , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Bovinos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Citrinina/química , Citrinina/toxicidade , Relação Dose-Resposta a Droga , Interações Medicamentosas/fisiologia , Macrófagos/efeitos dos fármacos , Micotoxinas/química , Micotoxinas/toxicidade , Ocratoxinas/química , Ocratoxinas/toxicidade , Penicillium/química
9.
Environ Health ; 15(1): 93, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27581612

RESUMO

BACKGROUND: Decreased muscle strength can lead to adverse health outcomes in the elderly. A potential association between phthalate exposure and muscle strength was suggested previously, but has not been investigated directly. We hypothesized that phthalate exposure is associated with lower handgrip strength and that the association is modified by the dietary omega-6 to omega-3 ratio. METHODS: We analyzed 1,228 participants (≥60 years of age) recruited in Seoul and Asan, Republic of Korea. The study participants were surveyed up to three times between 2012 and 2015. At every survey, we collected urine samples and measured handgrip strength twice for each hand. The associations between urine phthalate metabolite concentrations and handgrip strength were evaluated using linear mixed models. Based on dietary information from 391 individuals who participated in the first survey in Seoul, we evaluated the heterogeneity of the association for those with high and low omega-6 to omega-3 ratios, using 8.81 (the 75th quantile) as a cutoff value. RESULTS: Log-transformed creatinine-adjusted concentrations of mono-(2-ethyl-5-oxohexyl phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) were inversely associated with all measured handgrip strengths (ß = -0.69 to -0.42, all p-values < 0.05). Associations between phthalate biomarkers and handgrip strength did not differ by sex. When the dietary subgroup was stratified by the omega-6 to omega-3 ratio, the associations were stronger among participants with high ratios. CONCLUSIONS: We found inverse associations between phthalate biomarkers and handgrip strength in the elderly; this association was modified by the dietary omega-6 to omega-3 ratio.


Assuntos
Poluentes Ambientais/urina , Força da Mão , Ácidos Ftálicos/urina , Idoso , Idoso de 80 Anos ou mais , Dieta , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia
10.
Arch Environ Contam Toxicol ; 70(4): 647-56, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26706926

RESUMO

Arsenic (As) is a major environmental pollutant and a known human carcinogen that is widely distributed in the air, soil, and water. General population is mainly exposed to As through drinking water and food from the contaminated water and soil. Arsenic in drinking water is generally well controlled now. This study was performed to estimate total and inorganic As intake and to determine the major contributing source in the Korean adult diet. The study subjects were 2117 healthy adults (922 males and 1195 females) who had not been occupationally exposed to As. Total dietary intake was studied using the 24-h recall method, which included 138 specific food items. The estimates of total As and inorganic As intake were based on total and inorganic As contents in each food item consumed during the last 24 h. Daily dietary intake was estimated to be 1373.6 g. Total As intake was estimated to be 145.4 µg As/day. Total dietary As intake was correlated with consumption of fish/shellfish, seaweeds, and grains. Approximately 87% of total dietary As intake was attributed to seafood, such as 105.5 µg As/day from fish/shellfish and 20.5 µg As/day from seaweeds. Inorganic As intake was estimated to be 10.4 µg As per day. Inorganic As intake was mainly provided by grains (6.4 µg As/day), followed by seaweeds and fish/shellfish. Our results indicate that seafood and grains are the main As dietary sources in Korean adults and that dietary As exposure may be associated with individual dietary habits and environmental As contamination among countries.


Assuntos
Arsênio/análise , Dieta/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Poluentes Químicos da Água/análise , Adulto , Feminino , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Alimentos Marinhos/estatística & dados numéricos
11.
J Nanosci Nanotechnol ; 15(7): 5446-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26373157

RESUMO

Recently, fullerene derivatives have received significant attention due to their potential impacts on the development of high performance organic photovoltaic (OPV) cells. One of the most successful fullerene derivatives thus far is [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM), which is being used as an electron acceptor material. However, PCBM has some disadvantages concerning its application in OPV cells, such as a weak absorption rate in the visible region and a relatively low LUMO level. In the present work, we synthesized a novel fullerene derivative, called hexyl perylene fullerene (HPF), which contains a hexyl perylene moiety. The HPF molecules showed two absorption peaks at 340 nm and 450 nm corresponding to the fullerene and to the perylene moiety, respectively. 1,8-octanedithiol was used as an additive to improve the compatibility between the poly(3-hexylthiophene) (P3HT) and the synthesized HPF The characteristics of an OPV cell composed of ITO/PEDOT:PSS/P3HT:HPF:1,8-octanedithiol/Al were investigated.


Assuntos
Fulerenos/química , Perileno/química , Energia Solar
12.
BMC Pulm Med ; 15: 125, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26490046

RESUMO

BACKGROUND: Asthma is characterized by airway inflammation, and bronchial airways are particularly susceptible to oxidant-induced tissue damage. OBJECTIVE: To investigate the effect of dietary antioxidant intake and environmental tobacco smoke (ETS) on the risk of childhood asthma according to genotypes susceptible to airway diseases. METHODS: This cross-sectional study included 1124 elementary school children aged 7-12 years old. Asthma symptoms and smoking history were measured using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Intake of vitamin A (including retinol and ß-carotene), C, and E was measured by a semi-quantitative food frequency questionnaire (FFQ). GSTP1 polymorphisms were genotyped from peripheral blood samples. RESULTS: ETS was significantly associated with presence of asthma symptoms (adjusted odds ratio [aOR], 2.48; 95 % confidence interval [CI], 1.29-4.76) and diagnosis (aOR, 1.91; 95 % CI, 1.19-3.06). Dietary antioxidant intake was not associated with asthma symptoms, although ETS plus low vitamin A intake showed a significant positive association with asthma diagnosis (aOR, 2.23; 95 % CI, 1.10-4.54). Children with AA at nucleotide 1695 in GSTP1 who had been exposed to ETS and a low vitamin A intake have an increased risk of asthma diagnosis (aOR, 4.44; 95 % CI,1.58-12.52) compared with children who had not been exposed to the two risk factors. However, ETS exposure and low vitamin A intake did not significantly increase odds of asthma diagnosis in children with AG or GG genotypes. CONCLUSION: Low vitamin A intake and ETS exposure may increase oxidative stress and thereby risk for childhood asthma. These relationships may be modified by gene susceptibility alleles of GSTP1.


Assuntos
Asma/epidemiologia , Dieta/estatística & dados numéricos , Interação Gene-Ambiente , Glutationa S-Transferase pi/genética , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Vitaminas , Ácido Ascórbico , Asma/genética , Criança , Estudos Transversais , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Razão de Chances , Polimorfismo Genético , Vitamina A , Vitamina E , beta Caroteno
14.
Soft Matter ; 10(21): 3726-37, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24686378

RESUMO

The effect of coating thickness and sequence on the multi-wall carbon nanotube (MWCNT) surface on electrorheological (ER) activity is investigated. Silica-coated MWCNTs with different shell thicknesses and inorganic-coated MWCNTs with different shell sequences are fabricated using the sol-gel process. The morphology and elemental analyses of the core-shell structured MWCNTs were performed and the effect of coating thickness and coating materials on the MWCNT surface on ER and dielectric properties of inorganic-coated MWCNT suspensions have been analyzed from the measurement results of shear stress, viscosity, current density and permeability. The electrical conductivity of silica-coated MWCNTs decreases with an increase of the shell thickness. However, the dynamic yield stress and viscoelastic properties under an external electric field increased when the shell thickness reached 20 nm and then decreased with the thickness up to 40 nm. However, the titania-coated MWCNT suspension with a shell thickness of 40 nm showed the highest dynamic yield stress compared to the other core-shell structured MWCNT suspension at the same volume fraction. It has been found that the material of the outermost shell plays an important role in the ER performance. It has been concluded that the electrical conductivity and the permittivity of the MWCNTs can be controlled by adjusting the coating thickness and sequence of inorganic materials.

15.
J Nanosci Nanotechnol ; 14(8): 6181-4, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25936083

RESUMO

In the previous work, we have reported that organic photovoltaic (OPV) cells using DMDCNQI as an n-type second dopant material showed a high power conversion efficiency (PCE). In the present work, we have synthesized a novel DHDCNQI with long alkyl chains to improve the compatibility between the DHDCNQI dopant molecule and host P3HT polymer. We have fabricated OPV cells consisting of ITO/PEDOT:PSS/P3HT:PCBM:DHDCNQI/Al. We have investigated the characteristics of theses OPV cells using DCNQI derivative dopants from the measurements of the incident photon-to-current collection efficiency and photocurrent. The OPV cell using 3 wt% DHDCNQI exhibited a high PCE of 3.29% due to the high charge separation efficiency, good compatibility and low trap site effect.


Assuntos
Luz , Nitrilas/química , Semicondutores
16.
J Nanosci Nanotechnol ; 14(8): 6305-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25936108

RESUMO

In the present work, we have fabricated organic photovoltaic cells consisting of ITO/PEDOT:PSS/P3HT:PCBM/DMDCNQI/Al using a dip-coating method with various solvent systems. We have investigated solvent effects (such as solubility, viscosity and vapor pressure) in deposition of a thin DMDCNQI buffer layer on the performance of organic photovoltaic cells. The solvent system which had low viscosity and good solubility properties, made a dense and uniform DMDCNQI ultra thin film, resulting in a high performance device. In particular, a prepared organic photovoltaic cell was fabricated using a cosolvent system (methanol:methylenechloride = 3:1) and showed a maximum power conversion efficiency of 4.53%.


Assuntos
Cianetos/química , Compostos Orgânicos/química , Solventes/química , Soluções Tampão
17.
Public Health Nutr ; 17(11): 2563-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24182449

RESUMO

OBJECTIVE: To investigate the associations of behavioural problems with dietary patterns and weight status in young children. DESIGN: We assessed poor social skills and behavioural problems with a seventy-six-item Preschool and Kindergarten Behavior Scale (PKBS) and found three dietary patterns ('Korean healthy', 'animal foods' and 'sweets') in food/food group intake data assessed by an FFQ and analysed using factor analysis. Multiple logistic regression analyses were used to assess the association of diet and weight status with behaviour. SETTING: Pre-schools in the metropolitan areas of Korea. SUBJECTS: A total of 1458 children (mean age 5·2 (sd 0·9) years) from the Practical Approach for Better Maternal and Child Nutrition and Health Study conducted from 2001 to 2005. RESULTS: The 'Korean healthy' pattern showed a significant inverse association with poor social skills in the second highest quartile group (OR = 0·42; 95 % CI 0·21, 0·82) compared with the lowest quartile group for boys. For girls, the 'sweets' pattern was associated with a greater risk of poor social skills (OR = 3·41; 95 % CI 1·29, 9·01 at Q4 v. Q1) and problem behaviours (OR = 2·80; 95 % CI 1·05, 7·43 at Q4 v. Q1). Regarding weight status, both underweight and overweight boys had a higher risk of poor social skills than normal-weight boys. CONCLUSIONS: Dietary patterns and weight status are important indicators for the behaviour of young children. Healthy and unhealthy dietary patterns, underweight and overweight status, and gender differences should thus be considered for further studies.


Assuntos
Peso Corporal , Comportamento Infantil , Dieta , Índice de Massa Corporal , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Estudos Transversais , Carboidratos da Dieta/análise , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Ingestão de Energia , Feminino , Humanos , Modelos Logísticos , Masculino , Micronutrientes/análise , Avaliação Nutricional , República da Coreia , Comportamento Social , Fatores Socioeconômicos , Inquéritos e Questionários
18.
Int Arch Occup Environ Health ; 87(5): 501-13, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23824410

RESUMO

PURPOSE: Mercury (Hg) is a nonessential and toxic metal that is widely distributed in the environment. This study was performed to estimate the representative blood Hg level, to determine the contributing factors to Hg exposure, and to analyze the association of blood Hg with metabolic syndrome in Korean adults. METHODS: Mercury exposure is assessed by total Hg concentration in blood. A total of 2,114 healthy adults who have not been exposed to Hg occupationally were sampled by the multistaged, sex-, and age-stratified probability method. Information was collected regarding the subjects' demographic characteristics, lifestyles, and past medical history. The participants then underwent physical examination and blood sampling. RESULTS: The geometric mean concentration of Hg in whole blood was 3.90 µg/L, which was significantly influenced by sex, age, smoking, alcoholic consumption, residence area, and seafood intake after adjustment for confounders. Significant increases in body mass index, waist circumference, diastolic blood pressure, total cholesterol, and triglyceride were observed according to the blood Hg levels after adjustment for covariates. Also, Hg exposure was significantly associated with metabolic syndrome and their components such as obesity and increased fasting glucose. CONCLUSION: The blood Hg level in Korean adults is higher than that in USA and other Western countries, while it is similar to or lower than that in other Asian countries. The blood Hg level is influenced by sociodemographic factors and individual lifestyles including dietary habits. Furthermore, blood Hg is associated with metabolic syndrome, in which Hg exposure may play a role as a possible risk factor for cardiovascular diseases.


Assuntos
Exposição Ambiental/análise , Poluentes Ambientais/análise , Mercúrio/sangue , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Fatores Etários , Consumo de Bebidas Alcoólicas/epidemiologia , Povo Asiático , Glicemia , Índice de Massa Corporal , Pesos e Medidas Corporais , Humanos , Estilo de Vida , Lipídeos/sangue , República da Coreia/epidemiologia , Características de Residência , Fatores de Risco , Alimentos Marinhos , Fatores Sexuais , Fumar/epidemiologia , Fatores Socioeconômicos
19.
BMC Pulm Med ; 14: 109, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24990471

RESUMO

BACKGROUND: This paper describes the background, aim, and design of a prospective birth-cohort study in Korea called the COhort for Childhood Origin of Asthma and allergic diseases (COCOA). COCOA objectives are to investigate the individual and interactive effects of genetics, perinatal environment, maternal lifestyle, and psychosocial stress of mother and child on pediatric susceptibility to allergic diseases. METHODS/DESIGN: The participants in COCOA represents a Korean inner-city population. Recruitment started on 19 November, 2007 and will continue until 31 December, 2015. Recruitment is performed at five medical centers and eight public-health centers for antenatal care located in Seoul. Participating mother-baby pairs are followed from before birth to adolescents. COCOA investigates whether the following five environmental variables contribute causally to the development and natural course of allergic diseases: (1) perinatal indoor factors (i.e. house-dust mite, bacterial endotoxin, tobacco smoking, and particulate matters 2.5 and 10), (2) perinatal outdoor pollutants, (3) maternal prenatal psychosocial stress and the child's neurodevelopment, (4) perinatal nutrition, and (5) perinatal microbiome. Cord blood and blood samples from the child are used to assess whether the child's genes and epigenetic changes influence allergic-disease susceptibility. Thus, COCOA aims to investigate the contributions of genetics, epigenetics, and various environmental factors in early life to allergic-disease susceptibility in later life. How these variables interact to shape allergic-disease susceptibility is also a key aim.The COCOA data collection schedule includes 11 routine standardized follow-up assessments of all children at 6 months and every year until 10 years of age, regardless of allergic-disease development. The mothers will complete multiple questionnaires to assess the baseline characteristics, the child's exposure to environmental factors, maternal pre- and post-natal psychological stress, and the child's neurodevelopment, nutritional status, and development of allergic and respiratory illnesses. The child's microbiome, genes, epigenetics, plasma cytokine levels, and neuropsychological status, the microbiome of the residence, and the levels of indoor and outdoor pollutants are measured by standard procedures. DISCUSSION: The COCOA study will improve our understanding of how individual genetic or environmental risk factors influence susceptibility to allergic disease and how these variables interact to shape the phenotype of allergic diseases.


Assuntos
Exposição Ambiental , Hipersensibilidade Imediata/epidemiologia , Hipersensibilidade Imediata/etiologia , Exposição Materna , Projetos de Pesquisa , Poluentes Atmosféricos , Asma/epidemiologia , Asma/etiologia , Criança , Pré-Escolar , DNA/análise , Dermatite Atópica/epidemiologia , Suscetibilidade a Doenças/epidemiologia , Epigênese Genética , Feminino , Sangue Fetal/química , Hipersensibilidade Alimentar/epidemiologia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Microbiota , Avaliação Nutricional , Exposição Paterna , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Estudos Prospectivos , República da Coreia , Sons Respiratórios , Rinite Alérgica/epidemiologia , Pele/microbiologia , Estresse Psicológico/epidemiologia , População Urbana
20.
Clin Exp Emerg Med ; 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38286510

RESUMO

Background: Emergency department (ED) triage systems are used to classify the severity and urgency of emergency patients, and Korean medical institutions use the Korean Triage and Acuity Scale (KTAS). During the coronavirus disease 2019 (COVID-19) pandemic, appropriate treatment for emergency patients was delayed due to various circumstances, such as overcrowding of EDs, lack of medical workforce resources, and increased workload on medical staff. The purpose of this study was to evaluate the accuracy of the KTAS in predicting the urgency of emergency patients during the COVID-19 pandemic. Methods: This study retrospectively reviewed patients who were treated in the ED during the pandemic period from January 2020 to June 2021. Patients were divided into COVID-19 screening-negative (SN group) and COVID-19 screening-positive (SP group) groups. We compared the predictability of the KTAS for urgent patients between the two groups. Results: Of 107,480 patients, the SN and SP groups included 62,776 (58.4%) and 44,704 (41.6%) patients, respectively. The odds ratios for severity variables at each KTAS level revealed a more evident discriminatory power of KTAS for severity variables in the SN group (p-value <0.001). The predictability of KTAS for severity variables was higher in the SN group than in the SP group (area under the curve, p-value <0.001). Conclusion: During the pandemic, the KTAS had low accuracy in predicting patients in critical conditions in the ED. Therefore, in future pandemic periods, supplementation of the current ED triage system should be considered in order to accurately classify the severity of patients.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA