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1.
Nanotechnology ; 35(27)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38522102

RESUMEN

To obtain high-quality SiNxfilms applicable to an extensive range of processes, such as gate spacers in fin field-effect transistors (FinFETs), the self-aligned quadruple patterning process, etc, a study of plasma with higher plasma density and lower plasma damage is crucial in addition to study on novel precursors for SiNxplasma-enhanced atomic layer deposition (PEALD) processes. In this study, a novel magnetized PEALD process was developed for depositing high-quality SiNxfilms using di(isopropylamino)silane (DIPAS) and magnetized N2plasma at a low substrate temperature of 200 °C. The properties of the deposited SiNxfilms were analyzed and compared with those obtained by the PEALD process using a non-magnetized N2plasma source under the same conditions. The PEALD SiNxfilm, produced using an external magnetic field (ranging from 0 to 100 G) during the plasma exposure step, exhibited a higher growth rate (∼1 Å/cycle) due to the increased plasma density. Additionally, it showed lower surface roughness, higher film density, and enhanced wet etch resistance compared to films deposited using the PEALD process with non-magnetized plasmas. This improvement can be attributed to the higher ion flux and lower ion energy of the magnetized plasma. The electrical characteristics, such as interface trap density and breakdown voltage, were also enhanced when the magnetized plasma was used for the PEALD process. Furthermore, when SiNxfilms were deposited on high-aspect-ratio (30:1) trench patterns using the magnetized PEALD process, an improved step coverage of over 98% was achieved, in contrast to the conformality of SiNxdeposited using non-magnetized plasma. This enhancement is possibly a result of deeper radical penetration enabled by the magnetized plasma.

2.
Sensors (Basel) ; 24(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38732990

RESUMEN

In this paper, a volumetric Rotman lens antenna operating at 28 GHz is proposed. The design formula and procedure were derived for the 3-D Rotman lens antenna. The number of tilted beams is 3 × 3. The six rectangular blocks are assembled using a metallic bolt. The input port consists of a waveguide, and the output port is made of an open-ended waveguide. The input and output waveguides are drilled in a flat conducting plate. The input and output port positions are optimized. Simulated and measured results show that the radiating beam is controlled almost exactly as calculated. Compared with the previous two-stage stacked Rotman lens antenna, the proposed Rotman lens antenna can dramatically decrease the antenna volume by approximately 75%.

3.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38612481

RESUMEN

The pathophysiology of functional bowel disorders is complex, involving disruptions in gut motility, visceral hypersensitivity, gut-brain-microbiota interactions, and psychosocial factors. Light pollution, as an environmental stressor, has been associated with disruptions in circadian rhythms and the aggravation of stress-related conditions. In this study, we investigated the effects of environmental stress, particularly continuous light exposure, on intestinal motility and inflammation using zebrafish larvae as a model system. We also evaluated the efficacy of probiotics, specifically Bifidobacterium longum (B. longum), at alleviating stress-induced constipation. Our results showed that continuous light exposure in zebrafish larvae increased the cortisol levels and reduced the intestinal motility, establishing a stress-induced-constipation model. We observed increased inflammatory markers and decreased intestinal neural activity in response to stress. Furthermore, the expressions of aquaporins and vasoactive intestinal peptide, crucial for regulating water transport and intestinal motility, were altered in the light-induced constipation model. Administration of probiotics, specifically B. longum, ameliorated the stress-induced constipation by reducing the cortisol levels, modulating the intestinal inflammation, and restoring the intestinal motility and neural activity. These findings highlight the potential of probiotics to modulate the gut-brain axis and alleviate stress-induced constipation. Therefore, this study provides a valuable understanding of the complex interplay among environmental stressors, gut function, and potential therapeutic strategies.


Asunto(s)
Bifidobacterium longum , Probióticos , Animales , Pez Cebra , Hidrocortisona , Estreñimiento/etiología , Estreñimiento/terapia , Probióticos/farmacología , Probióticos/uso terapéutico , Inflamación , Larva
4.
Nanotechnology ; 34(46)2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37531942

RESUMEN

Highly selective etching of silicon nitride over silicon oxide is one of the most important processes especially for the fabrication of vertical semiconductor devices including 3D NAND (Not And) devices. In this study, isotropic dry etching characteristics of SiNxand SiO2using ClF3/Cl2remote plasmas have been investigated. The increase of Cl2percent in ClF3/Cl2gas mixture increased etch selectivity of SiNxover SiO2while decreasing SiNxetch rate. By addition of 15% Cl to ClF3/Cl2, the etch selectivity higher than 500 could be obtained with the SiNxetch rate of ∼8 nm min-1, and the increase of Cl percent to 20% further increased the etch selectivity to higher than 1000. It was found that SiNxcan be etched through the reaction from Si-N to Si-F and Si-Cl (also from Si-Cl to Si-F) while SiO2can be etched only through the reaction from Si-O to Si-F, and which is also in extremely low reaction at room temperature. When SiNx/SiO2layer stack was etched using ClF3/Cl2(15%), extremely selective removal of SiNxlayer in the SiNx/SiO2layer stack could be obtained without noticeable etching of SiO2layer in the stack and without etch loading effect.

5.
Orthod Craniofac Res ; 26(2): 207-215, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36054615

RESUMEN

OBJECTIVE: The objective of the study was to investigate the post-surgical stability of clockwise rotation of the maxillary occlusal plane (MXOP) after Le Fort I osteotomy for posterior impaction and advancement, in skeletal Class III patients who had undergone two-jaw orthognathic surgery (2J-OGS). MATERIALS AND METHODS: The sample set consisted of 46 patients (18 males and 28 females). Using lateral cephalograms taken at the initial evaluation (T0), before 2J-OGS (T1), after 2J-OGS (T2) and at debonding (T3), the amount of MXOP change (criterion: 2° in ΔMXOP [between T2 and T3]) was used to assign patients to Group 1 (G1, high relapse, -3.09°) or Group 2 (G2, low relapse, -0.99°). Findings were statistically compared between the groups. RESULTS: Compared with G2, G1 exhibited more severe skeletal Class III relationships and a flatter MXOP at T0, a greater increase in ΔANB, and more clockwise rotation of ΔMXOP and ΔFMA between T1 and T2. G1 also showed a greater decrease in ΔANB, higher counterclockwise rotation of ΔMXOP and upward movement of U1 between T2 and T3. Regression analysis yielded the following equation: MXOP (ΔT2-T3) = -0.37 X MXOP (ΔT1-T2) -0.43. CONCLUSIONS: The higher the clockwise rotation of the MXOP during 2J-OGS in skeletal Class III patients, the greater the subsequent relapse (counterclockwise rotation) of the MXOP.


Asunto(s)
Maloclusión de Angle Clase III , Procedimientos Quirúrgicos Ortognáticos , Masculino , Femenino , Humanos , Maloclusión de Angle Clase III/cirugía , Mandíbula , Rotación , Oclusión Dental , Osteotomía Le Fort , Cefalometría , Maxilar/cirugía , Recurrencia , Estudios Retrospectivos
6.
Nanotechnology ; 31(26): 265302, 2020 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-32131063

RESUMEN

The etch characteristics of Si and TiO2 nanostructures for optical devices were investigated using pulse biased inductively coupled plasmas (ICP) with SF6/C4F8/Ar and BCl3/Ar, respectively, and the results were compared with those etched using continuous wave (CW) biased ICP. By using pulse biasing compared to CW biasing in the etching of the line/pillar nanostructures with various aspect ratios, there was a reduction of the aspect ratio dependent etching (ARDE) and therefore, uniform etch depths for nanostructures with different pattern widths, as well as the improvement of the etch profiles without any notching, were obtained not only for silicon nanostructures but also for TiO2 nanostructures. The investigation has determined that the improvement of etch profiles and reduced ARDE effect when using pulse biasing are related to the decreased surface charging caused by neutralization of the surface and the improved radical adsorption (or etch byproduct removal) on the etched surfaces during the pulse-off period for pulse biasing compared to CW biasing.

7.
Eur J Nutr ; 58(8): 3255-3266, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30498867

RESUMEN

PURPOSE: Foods such as grains and vegetables are the dominant sources of exposure to cadmium, which has been classified as a carcinogen by various public health agencies. Cadmium exposure is a growing concern due to its associations with numerous harmful health effects, including gastric cancer risk. The objective of this study was to investigate the association of dietary cadmium intake and the consumption of cadmium-contributing foods with early gastric cancer risk. METHODS: A case-control study including 1245 subjects (cases, 415; controls, 830) was conducted in Korea. The dietary cadmium intake and the consumption of cadmium-contributing foods were assessed using a semi-quantitative food frequency questionnaire. RESULTS: After adjustment for covariates, the gastric cancer risk was increased for participants in the highest tertile of cadmium intake [odds ratios (ORs) 1.33, 95% confidence intervals (95% CIs) 0.94-1.88], but there was no significance. Both female (ORs 2.71, 95% CIs 1.37-5.36) and male (ORs 1.63, 95% CIs 1.07-2.50) participants in the highest tertile of rice consumption had a higher gastric cancer risk than did those in the lowest tertile. Men in the highest tertile of crab consumption had a gastric cancer risk 2.23 times greater than that of men in the lowest tertile (ORs 2.23, 95% CIs 1.21-4.13), but a difference was not seen in women. CONCLUSIONS: Future studies examining the causal effects of dietary cadmium intake and the consumption of cadmium-contributing foods on early gastric cancer risk in large-scale prospective cohorts are recommended.


Asunto(s)
Cadmio/administración & dosificación , Dieta/métodos , Neoplasias Gástricas/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Factores de Riesgo , Encuestas y Cuestionarios
8.
J Korean Med Sci ; 34(11): e97, 2019 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-30914907

RESUMEN

BACKGROUND: Because there has been a recent increase in refugee applications in Korea, the mental health of these refugees merits greater study. METHODS: We surveyed 129 refugees (including those in process of refugee application) and 121 migrant workers living in urban communities, using: the Patient Health Questionnaire-9 for depressive symptoms, the Impact Event Scale-Revised for post-traumatic stress disorder (PTSD) symptoms, and the health questionnaires used in 2016 Korean National Health and Nutrition Examination Survey (KNHANES). The majority of refugee subjects were from sub-Saharan Africa and Middle East. We compared the prevalence of possible depression and possible PTSD between refugees and migrant workers and refugees and age-gender matched samples from the KNHANES 2016. RESULTS: Frequency of suicidal planning during the last year was higher in the refugee group than Korean nationals, but frequency of suicidal attempt was not. High risk drinking was found in 0.8% of refugees, 6.6% of migrant workers and 27.2% of Korean nationals. Possible depression was present in 42.9% of refugee subjects, 33.3% of migrant workers, and 4.2% of Korean controls. Possible PTSD was present in 38.9% of refugees compared to 12.5% of migrant workers. Only major risk factor for depression among refugees was a traumatic event before entering Korea. CONCLUSION: Possible depression and PTSD are significantly more prevalent in refugees, compared to both migrant workers and Korean nationals. Prevalence rates are commensurate with refugee studies worldwide. Appropriate early screening and intervention schemes need to be developed for refugees entering Korea.


Asunto(s)
Trastorno Depresivo/epidemiología , Refugiados/psicología , Trastornos por Estrés Postraumático/epidemiología , Adulto , Consumo de Bebidas Alcohólicas , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Prevalencia , Calidad de Vida , República de Corea , Ideación Suicida
9.
J Sport Rehabil ; 28(6): 552-557, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29584576

RESUMEN

CONTEXT: Several factors, such as balance and respiration training programs, have been identified as contributing to a shooting performance. However, little is known about the benefits of these programs on the shooting records of adolescent air rifle athletes. OBJECTIVE: The purpose of this study was to investigate whether balance and respiration training can contribute to the shooting performance required for adolescent air rifle shooting athletes. DESIGN: Case-control study. SETTING: Shooting range. PARTICIPANTS: A total of 21 adolescent air rifle athletes were recruited from the local school community and assigned to an experimental (n = 11; EG) or control (n = 10; CG) group. INTERVENTION: The EG performed respiration and balance training for 30 minutes 3 times a week for 6 weeks, and the CG performed balance training only. MAIN OUTCOME MEASURES: Data were collected on the respiratory function, muscle activity, and shooting record before and after the 6-week intervention. RESULTS: The forced vital capacity (FVC), forced expired volume in 1 second (FEV1), FEV1 as a percentage of FVC, peak expiratory flow, and maximum voluntary ventilation were significantly increased in the EG, and FEV1 as a percentage of FVC was significantly increased in the CG (P < .05). The FVC and peak expiratory flow postintervention were significantly different between the groups (P < .05). The activity of the right internal oblique (IO) and left IO muscles of the FVC were significantly different in the EG (P < .05). Within-group changes in right external oblique, right IO, and left IO of the maximum voluntary ventilation were significantly increased in the EG (P < .05). The right IO and left IO activity improved more significantly in the EG than CG (P < .05). There was no difference between the groups with respect to the shooting records. CONCLUSIONS: The clinical significance of this study is the balance and respiration training affected the respiration function capacity and muscle activity, but did not affect the shooting record. Nevertheless, these training are a potential approach method to improve athletes' shooting record.


Asunto(s)
Rendimiento Atlético , Equilibrio Postural , Respiración , Deportes , Adolescente , Atletas , Estudios de Casos y Controles , Femenino , Armas de Fuego , Volumen Espiratorio Forzado , Humanos , Masculino , Ventilación Voluntaria Máxima , Capacidad Vital
10.
11.
Phytother Res ; 31(2): 321-329, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27910195

RESUMEN

The aim of this study was to investigate the neuroprotective effect of mulberrofuran G (MG) in in vitro and in vivo models of cerebral ischemia. MG was isolated from the root bark of Morus bombycis. MG inhibited nicotinamide adenine dinucleotide phosphate oxidase (NOX) enzyme activity and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced NOX4 protein expression in SH-SY5Y cells. MG inhibited the expression of activated caspase-3 and caspase-9 and cleaved poly adenine dinucleotide phosphate-ribose polymerase in OGD/R-induced SH-SY5Y cells. In addition, MG protected OGD/R-induced neuronal cell death and inhibited OGD/R-induced reactive oxygen species generation in SH-SY5Y cells. In in vivo model, MG-treated groups (0.2, 1, and 5 mg/kg) reduced the infarct volume in middle cerebral artery occlusion/reperfusion-induced ischemic rats. The MG-treated groups also reduced NOX4 protein expression in middle cerebral artery occlusion/reperfusion-induced ischemic rats. Furthermore, protein expression of 78-kDa glucose-regulated protein/binding immunoglobulin protein, phosphorylated IRE1α, X-box-binding protein 1, and cytosine enhancer binding protein homologous protein, mediators of endoplasmic reticulum stress, were inhibited in MG-treated groups. Taken together, MG showed protective effect in in vitro and in vivo models of cerebral ischemia through inhibition of NOX4-mediated reactive oxygen species generation and endoplasmic reticulum stress. This finding will give an insight that inhibition of NOX enzyme activity and NOX4 protein expression could be a new potential therapeutic strategy for cerebral ischemia. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Benzofuranos/química , Isquemia Encefálica/tratamiento farmacológico , Estrés del Retículo Endoplásmico/efectos de los fármacos , NADPH Oxidasas/metabolismo , Fármacos Neuroprotectores/farmacología , Terpenos/química , Animales , Benzofuranos/uso terapéutico , Muerte Celular , Masculino , NADPH Oxidasa 4 , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno , Transducción de Señal , Terpenos/uso terapéutico
12.
J Phys Ther Sci ; 29(10): 1715-1719, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29184275

RESUMEN

[Purpose] The study investigated the effects of lower extremity injuries on aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function in high school soccer players. [Subjects and Methods] The study assessed U High School soccer players (n=40) in S area, South Korea, divided into 2 groups: a lower extremity injury group (n=16) comprising those with knee and ankle injuries and a control group (n=24) without injury. Aerobic exercise capacity, anaerobic power, and knee isokinetic muscular function were compared and analyzed. [Results] Regarding the aerobic exercise capacity test, significant differences were observed in maximal oxygen uptake and anaerobic threshold between both groups. For the anaerobic power test, no significant difference was observed in peak power and average power between the groups; however, a significant difference in fatigue index was noted. Regarding the knee isokinetic muscular test, no significant difference was noted in knee flexion, extension, and flexion/extension ratio between both groups. [Conclusion] Lower extremity injury was associated with reduced aerobic exercise capacity and a higher fatigue index with respect to anaerobic exercise capacity. Therefore, it seems necessary to establish post-injury training programs that improve aerobic and anaerobic exercise capacity for soccer players who experience lower extremity injury.

13.
Opt Express ; 24(26): 29568-29576, 2016 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-28059343

RESUMEN

The development of low-frequency-driven liquid crystal displays (LCDs) has recently received intense attention to open up low-power consumption display devices, such as portable displays, advertising panels and price tags. In fringe-field switching (FFS) LCD mode, a unidirectional electric field gives rise to head-tail symmetry breaking in liquid crystals, so that the flexoelectric effect, a coupling between the elastic distortion and the electric polarization, becomes enormously significant. The effect is thus linked to an unusual optical effect, which badly damages the quality of images by image-flickering, and this image-flickering is mainly caused by transmittance difference between the applied signal frames. Here, we intensively investigate the mechanism of the transmittance deviation, and propose an essential and promising approach to solve the poor image-quality, that is, symmetrization of electric fields between the frames. The result of our work clearly demonstrates that the field-symmetry is crucial to reduce the image-flickering, and it can be obtained by optimization of the thickness of an insulation layer with respect to the ratio of the space between electrodes to the electrode width.

14.
Cardiovasc Diabetol ; 15(1): 122, 2016 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-27565571

RESUMEN

BACKGROUND: Acid-base imbalance has been reported to increase incidence of hypertension and diabetes. However, the association between diet-induced acid load and cardiovascular disease (CVD) risk in the general population has not been fully investigated. METHODS: This was a population-based, retrospectively registered cross-sectional study using nationally representative samples of 11,601 subjects from the Korea National Health and Nutrition Examination Survey 2008-2011. Individual CVD risk was evaluated using atherosclerotic cardiovascular disease (ASCVD) risk equations according to 2013 ACC/AHA guideline assessment in subjects aged 40-79 without prior CVD. Acid-base status was assessed with both the potential renal acid load (PRAL) and the dietary acid load (DAL) scores derived from nutrient intake. RESULTS: Individuals in the highest PRAL tertile had a significant increase in 10 year ASCVD risks (9.6 vs. 8.5 %, P < 0.01) and tended to belong to the high-risk (10 year risk >10 %) group compared to those in the lowest PRAL tertile (odds ratio [OR] 1.23, 95 % confidence interval [CI] 1.22-1.35). The association between higher PRAL score and high CVD risk was stronger in the middle-aged group. Furthermore, a multiple logistic regression analysis also demonstrated this association (OR 1.20 95 % CI 1.01-1.43). Subgroup analysis stratified obesity or exercise status; individuals in unhealthy condition with lower PRAL scores had comparable ASCVD risk to people in the higher PRAL group that were in favorable physical condition. In addition, elevated PRAL scores were associated with high ASCVD risk independent of obesity, exercise, and insulin resistance, but not sarcopenia. Similar trends were observed with DAL scores. CONCLUSION: Diet-induced acid load was associated with increased risk of CVD, independent of obesity and insulin resistance.


Asunto(s)
Equilibrio Ácido-Base , Desequilibrio Ácido-Base/epidemiología , Ácidos/efectos adversos , Enfermedades Cardiovasculares/epidemiología , Dieta/efectos adversos , Desequilibrio Ácido-Base/diagnóstico , Desequilibrio Ácido-Base/fisiopatología , Adulto , Anciano , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/fisiopatología , Distribución de Chi-Cuadrado , Comorbilidad , Estudios Transversales , Femenino , Humanos , Concentración de Iones de Hidrógeno , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Evaluación Nutricional , Encuestas Nutricionales , Oportunidad Relativa , República de Corea , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
15.
J Nat Prod ; 79(8): 1938-51, 2016 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-27420919

RESUMEN

Seventy-five compounds, including 21 new compounds (1-21), were isolated from the root bark of Cudrania tricuspidata. The structures of the isolated compounds were elucidated by interpretation of their spectroscopic data. All isolated compounds were evaluated for their neuroprotective effects against 6-hydroxydopamine (6-OHDA)-induced cell death, and nine compounds had activities with EC50 values of 1.9-30.2 µM. The 75 isolated compounds along with 34 previously reported xanthones were tested also for neuroprotective effects against the 1-methyl-4-phenylpyridinium ion (MPP(+)) and oxygen glucose deprivation (OGD)-induced cell death. Three compounds were active against MPP(+)-induced cell death with EC50 values of 0.2-10.3 µM, and 23 compounds were active in the OGD model with EC50 values of 2.9-35.5 µM.


Asunto(s)
Moraceae/química , Fármacos Neuroprotectores/aislamiento & purificación , Fármacos Neuroprotectores/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Corteza de la Planta/química , Raíces de Plantas/química , Xantonas/aislamiento & purificación , Xantonas/farmacología , Animales , Muerte Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Glucosa/metabolismo , Isquemia/tratamiento farmacológico , Fármacos Neuroprotectores/química , Resonancia Magnética Nuclear Biomolecular , República de Corea , Xantonas/química
16.
BMC Pediatr ; 16(1): 156, 2016 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-27659349

RESUMEN

BACKGROUND: Because the developing brain of a child is vulnerable to environmental toxins, even very low concentration of neurotoxin can affect children's neurodevelopment. Lead is a neurotoxic heavy metal which has the harmful effect on the striatal-frontal circuit of brain. This area of the brain is known to be closely related to attention deficit hyperactivity disorder (ADHD) pathophysiology. The primary objective of the present study was to investigate whether elevated blood lead concentration is a risk factor for ADHD. The secondary objective was to examine the association between blood lead concentration and symptom severity. METHODS: We conducted a frequency-matched, hospital-based case-control study with 114 medically diagnosed ADHD cases and 114 controls. The participants were matched for age and sex. The diagnoses of ADHD were assessed with semi-structured diagnostic interviews. The participants completed the continuous performance test (CPT), and their parents completed the ADHD-rating scale (ADHD-RS). Blood lead concentrations were measured by using graphite furnace atomic absorption spectrometry featuring Zeeman background correction. RESULTS: Children with ADHD exhibited blood lead concentrations that were significantly higher than those of the controls ( 1.90 ± 086 µg/dℓ vs. 1.59 ± 0.68 µg/dℓ, p = 0.003). The log transformed total blood lead concentration was associated with a higher risk of ADHD (OR: 1.60, 95 % CI: 1.04-2.45, p < 0.05). The analysis also revealed that the children with blood lead concentrations above 2.30 µg/dℓ were at a 2.5-fold (95 % CI: 1.09-5.87, p < 0.05) greater risk of having ADHD. After adjusting for covariates, our multivariate regression models indicated that blood lead concentrations were not significantly associated with ADHD-RS or CPT profiles among the ADHD cases. CONCLUSION: Even low blood lead concentrations are a risk factor for ADHD in children. This study warrants primary prevention policies to reduce the environmental lead burden. Future studies may be required to ascertain the effects of lead on symptom severity in ADHD.

17.
J Nanosci Nanotechnol ; 15(11): 8617-21, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26726562

RESUMEN

Hybrid materials of ß-cyclodextrin multi-decorated halloysite nanotubes (HNTs-g-ßCD) were prepared by a facile route, which showed high efficiency for catalysis and dye adsorption. Initially, the surface of halloysite nanotubes (HNTs) was modified with poly(glycidyl methacrylate) by the reversible addition fragmentation chain transfer (RAFT) polymerization of glycidyl methacrylate having epoxy groups as a monomer. Subsequently, ß-cyclodextrin was conjugated with the modified HNTs to produce HNTs-g-ßCD by the epoxide ring-opening reaction of mono-6-deoxy-6-hexanediamine-ß-cyclodextrin. The nanocomposites were characterized by FT-IR, TGA, SEM, and TEM. The HNTs-g-ßCD composites could be used as a nano adsorbent for methylene blue and a catalyst in the oxidation reaction of benzyl alcohol owing to the unique structure of ß-cyclodextrin. The HNTs-g-ßCD shows promiseas potential multi-functional materials by a combination of ß-cyclodextrin and HNTs properties.


Asunto(s)
Silicatos de Aluminio/química , Colorantes/aislamiento & purificación , Nanopartículas/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , beta-Ciclodextrinas/química , Adsorción , Catálisis , Arcilla , Colorantes/química , Ensayo de Materiales , Azul de Metileno/aislamiento & purificación , Nanopartículas/ultraestructura , Nanoporos/ultraestructura , Tamaño de la Partícula , Porosidad , Ultrafiltración/métodos , Agua/química
18.
Public Health Nutr ; 18(8): 1369-77, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25167205

RESUMEN

OBJECTIVE: We aimed to evaluate the reproducibility and validity of the newly developed FFQ for the Korean National Health and Nutrition Examination Survey (KNHANES) and to estimate the measure's calibration factors. DESIGN: The 109-item FFQ was administered twice, approximately 9 months apart. We also collected four seasonal 3 d dietary records (DR) as a reference method. Correlation coefficients and joint classification were computed to compare intakes of energy, thirteen nutrients and eleven food groups between the two FFQ to evaluate reproducibility. For validity, de-attenuated and energy-adjusted correlation, joint classification and Bland-Altman statistics were calculated for energy and nutrients between the first FFQ and the DR. To calibrate the FFQ, we performed a linear regression analysis in which the DR were the dependent variables and FFQ, age and sex were the independent variables. SETTING: Seoul metropolitan area, Republic of Korea. SUBJECTS: A total of 126 adults aged 20-65 years. RESULTS: The average correlation coefficients measuring reproducibility were 0·54 for nutrients and 0·57 for food groups. The mean correlation coefficient measuring validity was 0·40 for all nutrients between the first FFQ and the DR. On average, 75 % of the participants were classified into the same or adjacent quartiles, while 5 % of the participants were grossly misclassified. The mean energy and nutrient intakes estimated by the calibrated FFQ were similar to the means estimated by the DR. CONCLUSIONS: The newly developed FFQ for assessing dietary intake in the KNHANES has acceptable reproducibility and modest validity compared with a 12 d DR collected over a 9-month period.


Asunto(s)
Encuestas Nutricionales , Encuestas y Cuestionarios , Adulto , Anciano , Calibración , Registros de Dieta , Ingestión de Energía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , República de Corea , Adulto Joven
19.
BMC Complement Altern Med ; 15: 247, 2015 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-26201852

RESUMEN

BACKGROUND: Dendropanax morbifera Léveille has been employed for the treatment of infectious diseases using folk medicine. In this study, we evaluated the antioxidant effects of a leaf extract of Dendropanax morbifera Léveille in the hippocampus of mercury-exposed rats. METHODS: Seven-week-old Sprague-Dawley rats received a daily intraperitoneal injection of 5 µg/kg dimethylmercury and/or oral Dendropanax morbifera Léveille leaf extract (100 mg/kg) for 4 weeks. Animals were sacrificed 2 h after the last dimethylmercury and/or leaf extract treatment. Mercury levels were measured in homogenates of hippocampal tissue, a brain region that is vulnerable to mercury toxicity. In addition, we measured reactive oxygen species production, lipid peroxidation levels, and antioxidant levels in these hippocampal homogenates. RESULTS: Treatment with Dendropanax morbifera Léveille leaf extract significantly reduced mercury levels in hippocampal homogenates and attenuated the dimethylmercury-induced increase in the production of reactive oxygen species and formation of malondialdehyde. In addition, this leaf extract treatment significantly reversed the dimethylmercury-induced reduction in the hippocampal activities of Cu, Zn-superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase. CONCLUSION: These results suggest that a leaf extract of Dendropanax morbifera Léveille had strong antioxidant effects in the hippocampus of mercury-exposed rats.


Asunto(s)
Antioxidantes/administración & dosificación , Araliaceae/química , Hipocampo/efectos de los fármacos , Mercurio/toxicidad , Extractos Vegetales/administración & dosificación , Animales , Catalasa/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/metabolismo , Hipocampo/enzimología , Hipocampo/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Hojas de la Planta/química , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
20.
J Nat Prod ; 77(8): 1893-901, 2014 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-25051453

RESUMEN

Seventeen new prenylated xanthones (1-17) were isolated from an ethyl acetate-soluble extract of root bark of Cudrania tricuspidata together with 17 previously identified xanthones. The structures of the new compounds were elucidated by spectroscopic methods. Six new compounds (3, 7, 8, 9, 15, and 16) and six known compounds (18-23) showed neuroprotective effects against 6-hydroxydopamine-induced cell death in human neuroblastoma SH-SY5Y cells, with EC50 values of 0.7-16.6 µM.


Asunto(s)
Moraceae/química , Fármacos Neuroprotectores/aislamiento & purificación , Fármacos Neuroprotectores/farmacología , Xantonas/aislamiento & purificación , Xantonas/farmacología , Muerte Celular/efectos de los fármacos , Humanos , Estructura Molecular , Neuroblastoma/inducido químicamente , Neuroblastoma/tratamiento farmacológico , Fármacos Neuroprotectores/química , Resonancia Magnética Nuclear Biomolecular , Oxidopamina/farmacología , Corteza de la Planta/química , Raíces de Plantas/química , República de Corea , Xantonas/química
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