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1.
Nanomicro Lett ; 15(1): 97, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37038025

RESUMEN

Thick electrodes can substantially enhance the overall energy density of batteries. However, insufficient wettability of aqueous electrolytes toward electrodes with conventional hydrophobic binders severely limits utilization of active materials with increasing the thickness of electrodes for aqueous batteries, resulting in battery performance deterioration with a reduced capacity. Here, we demonstrate that controlling the hydrophilicity of the thicker electrodes is critical to enhancing the overall energy density of batteries. Hydrophilic binders are synthesized via a simple sulfonation process of conventional polyvinylidene fluoride binders, considering physicochemical properties such as mechanical properties and adhesion. The introduction of abundant sulfonate groups of binders (i) allows fast and sufficient electrolyte wetting, and (ii) improves ionic conduction in thick electrodes, enabling a significant increase in reversible capacities under various current densities. Further, the sulfonated binder effectively inhibits the dissolution of cathode materials in reactive aqueous electrolytes. Overall, our findings significantly enhance the energy density and contribute to the development of practical zinc-ion batteries.

2.
Sensors (Basel) ; 22(19)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36236486

RESUMEN

Flexible capacitive pressure sensors with a simple structure and low power consumption are attracting attention, owing to their wide range of applications in wearable electronic devices. However, it is difficult to manufacture pressure sensors with high sensitivity, wide detection range, and low detection limits. We developed a highly sensitive and flexible capacitive pressure sensor based on the porous Ecoflex, which has an aligned airgap structure and can be manufactured by simply using a mold and a micro-needle. The existence of precisely aligned airgap structures significantly improved the sensor sensitivity compared to other dielectric structures without airgaps. The proposed capacitive pressure sensor with an alignment airgap structure supports a wide range of working pressures (20-100 kPa), quick response time (≈100 ms), high operational stability, and low-pressure detection limit (20 Pa). Moreover, we also studied the application of pulse wave monitoring in wearable sensors, exhibiting excellent performance in wearable devices that detect pulse waves before and after exercise. The proposed pressure sensor is applicable in electronic skin and wearable medical assistive devices owing to its excellent functional features.


Asunto(s)
Dispositivos Electrónicos Vestibles , Monitoreo Fisiológico , Porosidad , Presión
3.
Nutrients ; 14(11)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35684139

RESUMEN

Chronic diseases develop via complex pathways, depending on the degree of exposure to risk factors from early in life and childhood onward. Metabolic syndrome has multiple risk factors, including genetic factors, inappropriate diet, and insufficient physical activity. This study classified health-related behavior classes in childhood and adolescents and analyzed the direct and indirect effects of each class on the metabolic risk in inflammation-mediated pathways. We identified the health-related lifestyle classes based on health-related behavior indicators in subjects aged 3-15 years who participated in the Ewha Birth and Growth Cohort Study by using a latent class analysis. A mediation analysis was performed to access the direct and indirect effects of each class on the continuous metabolic syndrome score (cMetS), with the inflammatory index used as a mediating factor. Subjects were classified into inactive and positive lifestyle classes according to their characteristics. In the inactive lifestyle class, interleukin (IL)-6 and cMetS had a significant association. The study confirmed that IL-6 exerts a significant indirect effect between inactive lifestyle and cMetS. This result supports previous studies. Since the health behaviors of children and adolescents can affect the likelihood of subsequent metabolic syndrome, appropriate health behavior interventions for this period are needed.


Asunto(s)
Síndrome Metabólico , Adolescente , Niño , Estudios de Cohortes , Dieta , Conductas Relacionadas con la Salud , Humanos , Inflamación , Síndrome Metabólico/metabolismo
4.
J Prosthodont ; 28(7): 797-803, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31250506

RESUMEN

PURPOSE: To determine the accuracy of a digital manufacturing method for dental implant restorations on stock abutments using intraoral scanners and prefabricated stock-abutment libraries. MATERIALS AND METHODS: Two dental implants with internal hexagonal connections were placed in the mandibular second premolar and second molar areas of a partially edentulous dentoform model; stock abutments with a diameter of 5 mm, abutment height of 5.5 mm, and gingival cuff height of 2 mm were connected. The study model was scanned 10 times using a reference tabletop scanner and 5 types of intraoral scanners (IOSs). The data collected by 5 types of IOSs were divided into 3 groups, based on the type and matching of stock abutment library data: no library, optical library, and contact library groups. A total of 160 data files were analyzed, including reference data. The resulting data were used to evaluate trueness and precision. RESULTS: Trueness and precision values in the group in which library data of the stock abutment were not used were 42.0 to 76.3 µm and 30.5 to 99.7 µm; corresponding values when the library data using an optical scanner were matched were 51.2 to 73.4 µm and 26.3 to 62.8 µm, and those when contact scanner library data were used were 30.1 to 62.4 µm and 15.5 to 55.9 µm. Thus, the accuracy of the contact library group was significantly higher than the accuracies of the no library (p < 0.001) and optical library groups (p < 0.001). CONCLUSION: The application of prefabricated library data of stock abutments using a contact scanner improved the accuracy of scan data. Scan accuracy of the stock abutments differed significantly based on the type of scanner.


Asunto(s)
Implantes Dentales , Boca Edéntula , Diseño Asistido por Computadora , Pilares Dentales , Técnica de Impresión Dental , Humanos
5.
Asia Pac J Clin Nutr ; 24(3): 533-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26420197

RESUMEN

To improve the nutritional status of children and adolescents, it is critical to identify the barriers to the implementation of nutrition education in schools. We carried out a cross-sectional study by analyzing data from 121 subjects (45 nutrition teachers and 76 school dietitians). Among the personal, environmental and systematic barriers, the top four barriers to the implementation of nutrition education were heavy workload (4.28 points), lack of a systematic curriculum (4.12 points), lack of perception of nutrition education by school administrators and teachers (4.07 points), and lack of continuing education for nutrition teachers and school dietitians (4.05 points). Additionally, poor working conditions, such as low pay, were identified as significant barriers to nutrition education for school dietitians compared with nutrition teachers (4.33 vs 3.47 points, p<0.001). This research provides useful information for nutrition policy makers to promote nutrition education in schools in South Korea.


Asunto(s)
Educación en Salud/estadística & datos numéricos , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Política Nutricional , Servicios de Salud Escolar/estadística & datos numéricos , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea
6.
Implant Dent ; 23(5): 529-33, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25192155

RESUMEN

PURPOSE: The purpose of this study was to investigate in vivo histomorphometric differences in initial bone response to modified sand-blasted, large-grit, acid-etched (modSLA), and fluoride-modified (F-mod) implant surfaces in rabbit tibia models. MATERIALS AND METHODS: Field emission scanning electron microscopy (FE-SEM), confocal laser scanning microscopy (CLSM), and x-ray photoelectron spectroscopy (XPS) were used to determine surface characteristics. Each of 3 live New Zealand white rabbits received an F-mod implant in one tibia and a modSLA implant in the other. After 1 week, the rabbits were killed, and the undecalcified histologic slides were prepared. Bone-to-implant contact (BIC) ratio and bone area (BA) were calculated in a defined area under a light microscope. RESULTS: FE-SEM, CLSM, and XPS showed that the modSLA surface was significantly rougher than the F-mod, and that the F-mod surface had a very small amount of fluoride. However, despite these surface variances, histomorphometric analyses revealed no significant differences in either BIC or BA. CONCLUSIONS: Our results suggest that the in vivo effects of increased hydrophilicity, when added to a titanium dental implant surface, on early bone response may be similar to the effects of surface fluoride treatment.


Asunto(s)
Implantes Dentales , Fluoruros/química , Oseointegración , Titanio/química , Animales , Interacciones Hidrofóbicas e Hidrofílicas , Conejos , Propiedades de Superficie
7.
Int J Hematol ; 87(2): 203-209, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18301962

RESUMEN

Several studies have been performed on the association between non-Hodgkin's lymphoma (NHL) and the presence of certain human leukocyte antigens (HLA) class II alleles in Asian countries, and these studies have shown different results, according to the ethnicity, for the frequencies of the HLA class II alleles, and especially for HLA-DRB1. Therefore, the distribution of the HLA-A, B, C, DRB1, and DQB1 alleles in 89 Korean patients with NHL and also in 200 healthy Korean controls was investigated in this study. For the class I alleles, the frequencies of HLA-B51 was increased in patients with NHL and diffuse large B cell (DLBC) lymphoma compared with the normal control. For the class II alleles, the frequencies of the HLA-DRB1*09 and DQB1*03 alleles were increased in patients with NHL and DLBC lymphoma compared with the normal controls. Also, the B51-DRB1*09-DQB1*03 haplotype was significantly increased in the patients with NHL. These results suggest that some genes in HLA-B*51-DRB1*09-DQB1*03 haplotype may contribute to NHL susceptibility in the Korean population.


Asunto(s)
Antígenos HLA/genética , Haplotipos/genética , Linfoma no Hodgkin/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Prueba de Histocompatibilidad , Humanos , Corea (Geográfico) , Masculino , Persona de Mediana Edad
8.
Menopause ; 15(2): 296-303, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18090035

RESUMEN

OBJECTIVE: In Korea, human placental extract (HPE) has recently been used to treat various diseases (chronic liver diseases, menopause syndrome, chronic fatigue, skin pigment diseases, etc.), but evidence-based studies are not yet sufficient. The aim of this study was to examine the effects of HPE on menopausal symptoms, fatigue, and risk factors for cardiovascular disease in middle-aged Korean women in a randomized controlled trial. DESIGN: Korean women, aged 40 to 64 years, with menopausal symptoms and fatigue were recruited as participants. The women were randomly assigned to a placebo group or an HPE group. The HPE group received subcutaneous injections of HPE in the abdomen for 8 weeks, whereas the placebo group received normal saline. Then, the Menopause Rating Scale, and Fatigue Severity Scale, and Visual Analog Scale were administered, and risk factors for cardiovascular disease were assessed. RESULTS: The Menopause Rating Scale total baseline score was not different between the two groups; however, the score of the HPE group decreased significantly at 8 weeks compared with that of the placebo group (P = 0.033). Fatigue Severity Scale and Visual Analog Scale scores of the placebo group did not change, whereas the scores of the HPE group decreased significantly during the study period (Fatigue Severity Scale, P = 0.002; Visual Analog Scale, P = 0.001). The baseline 17beta-estradiol level was not significantly different between the two groups, but the 17beta-estradiol level of the HPE group was significantly increased at 8 weeks compared with that of the placebo group (P = 0.031). No changes in risk factors for cardiovascular disease were observed in either group. CONCLUSIONS: Menopausal symptoms and fatigue in middle-aged Korean women improved after 8 weeks of HPE treatment, whereas risk factors for cardiovascular disease did not change during the study period.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Fatiga/tratamiento farmacológico , Menopausia/efectos de los fármacos , Extractos Placentarios/uso terapéutico , Adulto , Enfermedades Cardiovasculares/epidemiología , Estradiol/metabolismo , Femenino , Humanos , Inyecciones Subcutáneas , Corea (Geográfico) , Persona de Mediana Edad , Extractos Placentarios/análisis , Factores de Riesgo
9.
J Clin Epidemiol ; 57(9): 978-84, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15504641

RESUMEN

OBJECTIVE: Our study aimed to determine whether depressive symptoms are associated with poor self-care behaviors among patients with type 2 diabetes. METHODS: Study subjects were 168 patients with diabetes, aged >30 years, who had a diabetes history of 1-15 years. Using a self-reported questionnaire, we evaluated diabetes self-care behaviors and depressive symptoms. Self-care behaviors were evaluated in five categories: medication taking, self-monitoring of blood glucose (SMBG), diet, exercise, and participation in patient education programs. Depressive symptoms were evaluated using the Centers for Epidemiologic Studies-Depression (CES-D) scales. Multiple logistic regression analyses were used to determine the association between self-care behaviors and depressive symptoms. RESULTS: Higher depressive-symptom scores were associated with poor self-care behaviors, significantly with poor participation in education programs (odds ratio OR=1.21, 95% confidence interval CI=1.06-1.38) and poor diet (OR=1.11, 95% CI=1.01-1.22), and marginally with poor medication taking (OR=1.14, 95% CI=1.00-1.31). Depressive symptoms were not significantly associated with either SMBG or exercise. CONCLUSIONS: These data suggest that the evaluation and control of depressive symptoms among diabetic patients would improve their adherence to self-care behaviors.


Asunto(s)
Depresión/psicología , Diabetes Mellitus Tipo 2/psicología , Cooperación del Paciente/psicología , Autocuidado/psicología , Adulto , Anciano , Automonitorización de la Glucosa Sanguínea/psicología , Depresión/etiología , Diabetes Mellitus Tipo 2/terapia , Ejercicio Físico/psicología , Femenino , Humanos , Hipoglucemiantes/administración & dosificación , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Escalas de Valoración Psiquiátrica , Factores de Riesgo
10.
Hum Immunol ; 64(10): 979-89, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14522096

RESUMEN

Cytokines play a crucial role in regulating the immune and inflammatory responses. The collective influence of several cytokines can regulate immune responses as complex as those underlying allograft rejections or autoimmune diseases. Polymorphisms in the regulatory regions of the cytokine genes may influence their expression. Therefore, the polymorphisms of cytokine genes are potentially important as genetic predictors of the disease susceptibility or clinical outcome. In 311 unrelated healthy Korean individuals, we investigated the polymorphisms of cytokine genes (interleukin-1 [IL-1], IL-2, IL-4, IL-6, IL-10, and interferon-gamma [IFN-gamma]), which had been previously reported to be associated with a number of immune diseases, transplant complications, and direct or indirect influences on the level of expression and production. And we also compared the results to those published for other populations. The genotype distributions were consistent with the assumption of the Hardy-Weinberg equilibrium, with the exceptions of IL-1B +3954 and IL-6-174 polymorphisms. The polymorphisms examined in this study were almost similar to that observed in Asian populations. There were significant differences of the polymorphisms, except for IL-4 receptor alpha +1902, between Korean and other populations. Comparing the alleles associated with higher level of expression and production, IL-1B +3954*T, IL-2-330*G, and IL-4-590*T alleles were significantly higher, and IL-1RN*A2, IL-10-1082*G, and IFN-gamma*2 alleles were lower in Koreans than other populations. Especially in IL-6 promoter -174 polymorphism, we found only the G allele associated with higher plasma IL-6 levels. In haplotype analysis of IL-10 promoter polymorphisms, the GCC haplotype, associated with higher expression of IL-10, was significantly lower in Koreans. These results may be helpful for understanding transplant-related complications, immune or autoimmune diseases, and malignant diseases in the Korean population.


Asunto(s)
Interferón gamma/genética , Interleucinas/genética , Frecuencia de los Genes , Humanos , Corea (Geográfico) , Polimorfismo Genético , Regiones Promotoras Genéticas
11.
Yonsei Med J ; 44(2): 265-72, 2003 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-12728467

RESUMEN

Constipation and the use of laxatives are relatively common in patients with diabetes mellitus. However, the mechanisms responsible for the constipation are unclear. Even though autonomic neuropathy is regarded as one of the important mechanisms of constipation, it requires further clarification. In addition, the colonic function in diabetic patients requires further investigation. The aim of this study was to compare the colonic transit time between patients with diabetes mellitus and healthy subjects, and correlate it to the presence of cardiovascular autonomic neuropathy. The colonic transit time was measured by a noninvasive, radio-opaque marker method, and the presence of cardiovascular autonomic neuropathy was evaluated by the beat-to-beat variation and the orthostatic hypotension. Constipation was defined by the Rome II criteria. The mean total colonic transit time of the 28 diabetic patients (34.9 +/- 29.6 h, mean +/- S.D.) was significantly longer than that of the 28 healthy subjects (20.4 +/- 15.6 h, p < 0.05). Among the diabetic patients, 9/28 (32%) had constipation and 14/28 (50%) had cardiovascular autonomic neuropathy. The diabetic patients with constipation showed longer total, left and recto-sigmoid colonic transit times than those without constipation. However, the mean colonic transit time of diabetic patients with and those without cardiovascular autonomic neuropathy was similar. In conclusion, other mechanisms than the mere presence of cardiovascular autonomic neuropathy might be more relevant to the development of constipation in patients with diabetes mellitus.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Colon/fisiopatología , Neuropatías Diabéticas/fisiopatología , Adulto , Anciano , Estreñimiento/fisiopatología , Femenino , Tránsito Gastrointestinal , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
12.
J Biol Chem ; 277(6): 3918-25, 2002 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-11723122

RESUMEN

A role for uncoupling protein (UCP) homologues in mediating the proton leak in mammalian mitochondria is controversial. We subjected insulinoma (INS-1) cells to adenoviral expression of UCP2 or UCP1 and assessed the proton leak as the kinetic relationship between oxygen use and the inner mitochondrial membrane potential. Cells were infected with different amounts of rat UCP2, and, in other experiments, with either UCP2 or UCP1. The relative molar expression of these subtypes was quantified through comparison with histidine-tagged UCP1 or UCP2 proteins engineered by expression in Escherichia coli. Adenoviral infection with UCP2, compared with beta-galactosidase, resulted in a dose-dependent shift in kinetics indicating increased H(+) flux at any given membrane potential. UCP1 also enhanced H(+) flux, but, on a relative molar basis, the overexpression of the endogenous protein, UCP2, was more potent than UCP1. These results were not due to nonspecific overexpression of mitochondrial protein since UCP1 activity was inhibited by GDP and because overexpression of another membrane carrier protein, the oxoglutarate malate carrier had no effect. UCP2-mediated H(+) conduction was not GDP sensitive. These data suggest that the UCP homologue, UCP2, mediates the proton leak in mitochondria of a mammalian cell wherein UCP2 is the native subtype.


Asunto(s)
Proteínas de Transporte de Membrana , Mitocondrias/metabolismo , Proteínas Mitocondriales , Proteínas/fisiología , Protones , Animales , Secuencia de Bases , Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/fisiología , Línea Celular , Cartilla de ADN , Escherichia coli/genética , Guanosina Difosfato/farmacología , Canales Iónicos , Transporte Iónico , Potenciales de la Membrana , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/fisiología , Mitocondrias/efectos de los fármacos , Proteínas/genética , Ratas , Proteína Desacopladora 1 , Proteína Desacopladora 2 , beta-Galactosidasa/genética
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