128 results on '"Young Hoon Lee"'
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2. Blue TADF Emitters Based on B-Heterotriangulene Acceptors for Highly Efficient OLEDs with Reduced Efficiency Roll-Off
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Young Hoon Lee, Donggyun Lee, Seunghyup Yoo, Min Hyung Lee, Taehwan Lee, Jaehoon Jung, and Woochan Lee
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chemistry.chemical_compound ,Materials science ,Photoluminescence ,Intersystem crossing ,chemistry ,Excited state ,Doping ,OLED ,General Materials Science ,Quantum efficiency ,Singlet state ,Methylene ,Photochemistry - Abstract
The design of robust boron acceptors plays a key role in the development of boron-based thermally activated delayed fluorescence (TADF) emitters for the realization of efficient and stable blue organic light-emitting diodes (OLEDs). Herein, we report a set of donor (D)-acceptor (A)-type blue TADF compounds (1-3) comprising triply bridged triarylboryl acceptors, the so-called B-heterotriangulenes, which differ depending on the identity of one of the bridging groups: methylene (1), dimethylmethylene (2), or oxo (3). The X-ray crystal structures of 2 and 3 reveal a highly twisted D-A connectivity and a completely planar geometry for the B-heterotriangulene rings. All compounds exhibit blue emissions with the unitary photoluminescence quantum yields and small singlet-triplet energy splitting (
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- 2021
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3. Effect of Systemic Hypertension on Peripapillary RNFL Thickness in Patients With Diabetes Without Diabetic Retinopathy
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Young-Hoon Lee, Gi-Seok Park, Hyung-Bin Lim, Woo-Hyuk Lee, Jung Yeul Kim, Min Su Kim, and Min-Woo Lee
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Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Visual Acuity ,Nerve fiber layer ,Type 2 diabetes ,chemistry.chemical_compound ,Diabetes mellitus ,Ophthalmology ,Healthy control ,Internal Medicine ,Humans ,Medicine ,In patient ,cardiovascular diseases ,Aged ,Retrospective Studies ,Glycated Hemoglobin ,Diabetic Retinopathy ,business.industry ,Retinal ,Diabetic retinopathy ,Middle Aged ,medicine.disease ,Cross-Sectional Studies ,medicine.anatomical_structure ,Diabetes Mellitus, Type 2 ,chemistry ,Hypertension ,Female ,business ,Tomography, Optical Coherence ,Retinal Neurons - Abstract
Type 2 diabetes mellitus (T2DM) and hypertension (HTN) are both relatively common systemic diseases and cause damage to the retina, such as inner retina reduction and microvascular impairment. The purpose of this study was to identify peripapillary retinal nerve fiber layer (pRNFL) damage by diabetic neurodegeneration and the effects of HTN on the pRNFL thickness in patients with T2DM without clinical diabetic retinopathy. Subjects were divided into three groups: healthy control subjects (group 1), patients with T2DM (group 2), and patients with both diabetes and HTN (group 3). The pRNFL thickness was measured using optical coherence tomography and compared among each group. Linear regression analyses were performed to identify factors associated with pRNFL thickness. A total of 325 eyes were included: 143 eyes in the group 1, 126 eyes in group 2, and 56 eyes in group 3. The mean pRNFL thicknesses of each group were 96.1 ± 7.7, 94.4 ± 8.6, and 91.6 ± 9.6 μm, respectively (P = 0.003). In multivariate linear analyses, diabetes duration (β = −0.236; P = 0.018) and HTN (β = −3.766; P = 0.008) were significant factors affecting the pRNFL thickness in groups 2 and 3. Additionally, the HTN duration was significantly correlated with pRNFL thickness in group 3 (R2 = 0.121; P = 0.008). In conclusion, patients with T2DM with HTN showed thinner pRNFL thickness than those with T2DM only. Additionally, the duration of HTN was significantly correlated with pRNFL thickness in patients with both diabetes and HTN.
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- 2021
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4. Association between Albumin, Total Bilirubin, and Uric Acid Serum Levels and the Risk of Cancer: A Prospective Study in a Korean Population
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Seong-Woo Choi, Ye Rim Kim, Chang Kyun Choi, Hye-Yeon Kim, Young Hoon Lee, Sun-Seog Kweon, and Min-Ho Shin
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Male ,medicine.medical_specialty ,Bilirubin ,Serum albumin ,neoplasms ,Gastroenterology ,chemistry.chemical_compound ,Internal medicine ,Republic of Korea ,Medicine ,Humans ,Prospective Studies ,Prospective cohort study ,biology ,business.industry ,Hazard ratio ,Albumin ,Cancer ,General Medicine ,medicine.disease ,Uric Acid ,antioxidants ,chemistry ,Oncology ,biology.protein ,Original Article ,business ,Liver cancer ,Body mass index - Abstract
Purpose In this prospective study, we evaluated the association between the serum levels of antioxidants uric acid (UA), albumin, and total bilirubin and the risk of cancer in a Korean population. Materials and methods A total of 15882 subjects were followed up for cancer development and cancer-related death. During the follow-up period, 1619 cancer diagnoses and 617 cancer-related deaths were recorded. Cox proportional regression was performed to calculate the hazard ratio (HR) per standard deviation (SD) increment and 95% confidence interval (CI). The model was adjusted for covariates such as the age, sex, smoking, alcohol consumption, physical activity, education level, body mass index, and family history. Sensitivity analyses using the study subjects with physiological serum levels of each indicator were also performed. Results UA levels were positively correlated with cancer risk (HR per SD increment 1.04; 95% CI, 1.01-1.09), and albumin levels were inversely associated with the overall cancer risk (HR, 0.92; 95% CI, 0.88-0.96) and cancer-related death (HR, 0.86; 95% CI, 0.80-0.93). Total bilirubin levels were negatively correlated with the risk of cancer-related death (HR, 0.91; 95% CI, 0.83-0.99). By cancer type, UA was positively associated with prostate cancer, total bilirubin was positively associated with liver cancer, and albumin was inversely associated with lung cancer. Conclusion The findings of this study support the role of antioxidants in carcinogenesis. Future large-cohort studies are needed to confirm the predictive value of albumin, UA, and total bilirubin levels in each type of cancer.
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- 2021
5. Sex-specific associations of habitual intake of soy protein and isoflavones with risk of type 2 diabetes
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Min-Ho Shin, Mi Kyung Kim, Bo Youl Choi, Young Hoon Lee, Dong Hoon Shin, and Hye Won Woo
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Male ,0301 basic medicine ,Physiology ,Genistein ,030209 endocrinology & metabolism ,Type 2 diabetes ,Critical Care and Intensive Care Medicine ,Rate ratio ,Diet Surveys ,Eating ,03 medical and health sciences ,chemistry.chemical_compound ,Sex Factors ,0302 clinical medicine ,Risk Factors ,Republic of Korea ,Humans ,Medicine ,Prospective Studies ,Soy protein ,Aged ,030109 nutrition & dietetics ,Nutrition and Dietetics ,business.industry ,Incidence ,Daidzein ,Middle Aged ,Isoflavones ,medicine.disease ,Diet ,Diabetes Mellitus, Type 2 ,chemistry ,Quartile ,Cohort ,Soybean Proteins ,Female ,business - Abstract
Summary Background & aims A possible mechanism by which intake of soy isoflavones leads to an improvement in glucose metabolism has been suggested. However, epidemiological evidence of a link between dietary soy isoflavone and type 2 diabetes is not convincing. This study aimed to evaluate the prospective associations between intake of dietary soy protein and isoflavones (total isoflavones, daidzein and genistein) and risk of type 2 diabetes in a community-based cohort of Korean adults aged ≥ 40 years, the Korean Multi-Rural Communities Cohort (MRCohort). Methods A total of 8269 participants who did not have type 2 diabetes were enrolled. Dietary intake was calculated using a food frequency questionnaire. Results Over 50,063 person-years of follow-up, 531 participants developed type 2 diabetes. Significant dose–response inverse associations were observed between dietary soy protein and isoflavones (quartiles) and type 2 diabetes in women (incidence rate ratio, IRR = 0.63, 95% CI = 0.45–0.87, P for trend = 0.0078 for soy protein; IRR = 0.62, 95% CI = 0.45–0.86, P for trend = 0.0031 for total isoflavones for the highest quartile compared with the lowest quartile). Similar significant linear trends were found for both daidzein and genistein. However, there were no significant associations with soy protein and isoflavones in men. The sex-specific differences in associations between soy protein and isoflavones intakes and type 2 diabetes risk were statistically significant (all P for interaction Conclusions Habitual intake of soy protein and isoflavones may be inversely associated with type 2 diabetes in women, but not in men. Dietary soy components may play different roles in the development of type 2 diabetes in men and women.
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- 2021
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6. Comparison of Retinal Layer Thicknesses of Highly Myopic Eyes and Normal Eyes
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Seung Kook Baek, Young Hoon Lee, Tae-Yeon Kim, and Min-Woo Lee
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Adult ,medicine.medical_specialty ,genetic structures ,Nerve fiber layer ,Outer plexiform layer ,Retinal Pigment Epithelium ,Retina ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,High myopia ,Ophthalmology ,Myopia ,medicine ,Humans ,Outer nuclear layer ,Ganglion cell layer ,Optical coherence tomography ,Choroid ,business.industry ,Retinal ,General Medicine ,Middle Aged ,Inner plexiform layer ,eye diseases ,medicine.anatomical_structure ,chemistry ,Inner nuclear layer ,030221 ophthalmology & optometry ,Original Article ,sense organs ,Individual retinal layer thickness ,business ,Tomography, Optical Coherence ,030217 neurology & neurosurgery - Abstract
Purpose To evaluate the differences in individual segmental retinal layer thickness in adult patients with high myopia. Methods This study compared the retinal layers of patients with high myopia (axial length of ≥26.0 mm) with those of normal controls using spectral-domain optical coherence tomography. The thicknesses of the retinal layers were compared using nine Early Treatment Diabetic Retinopathy Study subfields. Choroidal thickness was also measured in the subfoveal area. Results We included 37 eyes with high myopia and 37 eyes of healthy subjects. The mean age was 42.95 and 47.73 years (p = 0.114), and the mean axial length was 27.28 and 24.47 mm (p l 0.001), respectively. The parafoveal areas (outer ring segment) of the ganglion cell layer and inner plexiform layer, all segmental areas except the subfoveal region of the inner nuclear layer, most segmental areas (inner superior, inner inferior, outer superior, outer temporal, and outer nasal) of outer plexiform layer, and most segmental areas (subfovea, inner temporal, inner inferior, inner nasal, outer temporal, and outer inferior) of outer nuclear layer were thinner in eyes with high myopia than in normal eyes (all p l 0.05). There were no statistically significant differences between the levels of photoreceptor layer, retinal pigment epithelium, and nerve fiber layer. The mean choroidal thickness was 153.81 ± 64.80 and 239.54 ± 44.28 μm in the high myopia and control groups, respectively, which were significantly different (p l 0.001). Conclusions In high myopia without pathologic changes, there was a meaningful thinning of the retina and choroid, especially in most Early Treatment Diabetic Retinopathy Study subfield areas of the deep vascular complex, perifoveal area of the superficial vascular complex, and most areas of the outer nuclear layer in the outer retinal layer, which are associated with myopic axial elongation.
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- 2020
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7. Positive association of alcohol consumption with incidence of hypertension in adults aged 40 years and over: Use of repeated alcohol consumption measurements
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Sukyoung Jung, Hye Won Woo, Dong Hoon Shin, Nakyoung Lee, Mi Kyung Kim, Bo Youl Choi, Jinho Shin, Min-Ho Shin, and Young Hoon Lee
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Adult ,Male ,0301 basic medicine ,Alcohol Drinking ,Blood Pressure ,030209 endocrinology & metabolism ,Alcohol ,Rural Health ,Critical Care and Intensive Care Medicine ,Risk Assessment ,03 medical and health sciences ,chemistry.chemical_compound ,Sex Factors ,0302 clinical medicine ,Risk Factors ,Environmental health ,Republic of Korea ,Humans ,Medicine ,Prospective Studies ,Risk factor ,Prospective cohort study ,Aged ,030109 nutrition & dietetics ,Nutrition and Dietetics ,business.industry ,Incidence ,Incidence (epidemiology) ,Age Factors ,Repeated measures design ,Middle Aged ,Health Surveys ,Blood pressure ,chemistry ,Hypertension ,Female ,business ,Alcohol consumption - Abstract
Managing alcohol consumption may be an effective way of preventing hypertension, which is an important modifiable risk factor for cardiovascular diseases. However, there is little evidence on the temporal relationship between alcohol consumption and incidence of hypertension. We investigated the prospective association between repeated measures of alcohol consumption and hypertension incidence among Korean adults aged 40 and over.This study included a total of 4989 participants that were not taking antihypertensive drugs and had normal blood pressure (BP) (systolic 140 mmHg and diastolic 90 mmHg). We used three measures of alcohol consumption (baseline, most recent, and average) as exposures and compared the three approaches. Using a modified Poisson regression model with a robust error estimator, we estimated incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for hypertension.Over a total of 17,689 person-years (average 3.5 years of follow-up), 574 incident cases of hypertension were identified. In multivariable models, consuming ≥30 ml/d of alcohol was associated with a risk of hypertension among men (IRR = 1.72, 95% CI = 1.20-2.48, p trend = 0.017 for baseline alcohol consumption; IRR = 1.69, 95% CI = 1.23-2.33, p trend = 0.005 for the most recent alcohol consumption; IRR = 1.49, 95% CI = 1.09-2.03, p trend = 0.014 for average alcohol consumption). After additional adjustment for baseline BP the positive association remained only when the most recent alcohol consumption measure was used. There was no significant association between alcohol consumption and hypertension among women, and no interaction effect between alcohol consumption and baseline BP levels on incidence of hypertension (all p interaction 0.05) existed.Alcohol consumption, especially consuming ≥30 ml/d, may be positively linked with incidence risk of hypertension among men.
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- 2020
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8. Frustrated Lewis pairs with thermally activated delayed fluorescence properties: activation of formaldehyde
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Sang Uck Lee, Young Hoon Lee, Junseong Lee, Min Hyung Lee, and Eun Bi Nam
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Inorganic Chemistry ,chemistry.chemical_compound ,Chemistry ,Polymer chemistry ,Formaldehyde ,Fluorescence ,Acceptor ,Frustrated Lewis pair ,Adduct - Abstract
Activation of formaldehyde (FA) by frustrated Lewis pairs (FLPs) consisting of bulky phosphines with a donor–acceptor unit and B(C6F5)3 led to the formation of FLP–FA adducts that exhibit a thermally activated delayed fluorescence.
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- 2020
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9. Bifunctional NiCo2Se4 and CoNi2Se4 nanostructures: Efficient electrodes for battery-type supercapacitors and electrocatalysts for the oxygen evolution reaction
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Hyun-Chul Kim, Young-Hoon Lee, Yong-Han Yun, John Anthuvan Rajesh, Kwang-Soon Ahn, Soon-Hyung Kang, and Vu Hong Vinh Quy
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Supercapacitor ,Materials science ,Scanning electron microscope ,General Chemical Engineering ,Oxygen evolution ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Electrode ,0210 nano-technology ,Bifunctional ,Bimetallic strip - Abstract
We report the fabrication of bimetallic NiCo2Se4 and CoNi2Se4 nanostructures on nickel-foam (Ni-foam) substrates via a potentiostatic-deposition method by adjusting the molar ratio of Ni and Co metals. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses show that burl-like clusters with characteristic fluffy NiCo2Se4 and flake-like CoNi2Se4 hierarchical structures were deposited on the Ni-foam substrates. When used as battery-type electrodes in supercapacitors, both NiCo2Se4 and CoNi2Se4 electrodes exhibited outstanding capacity and good electrochemical properties. The CoNi2Se4 electrode delivered excellent capacity and cycling stability (602 C g–1 at 1 A g–1 and 98.30% retention after 5000 cycles at 40 A g–1) when compared to the NiCo2Se4 electrode (353 C g–1 at 1 A g–1 and 96.83% retention after 5000 cycles at 40 A g–1). Furthermore, as-deposited NiCo2Se4 and CoNi2Se4 hierarchical structures were employed as efficient electrocatalysts for water oxidation in alkaline solutions. NiCo2Se4 and CoNi2Se4 electrocatalysts showed low overpotentials of 257 and 244 mV in a 1.0 M KOH aqueous solution, respectively. The electrocatalysts also exhibited prolonged stability (NiCo2Se4 and CoNi2Se4 maintained currents of 95.6% and 97.5%, respectively, over 10 h), which makes them comparable to well-known Ni and Co-based catalysts. Collectively, the as-deposited NiCo2Se4 and CoNi2Se4 are the most efficient bifunctional electrodes and electrocatalysts for application in battery-type supercapacitors and the oxygen evolution reaction, respectively, and can potentially be applied for energy conversion and storage processes.
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- 2019
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10. Association between Alcohol Consumption and Serum Cortisol Levels: a Mendelian Randomization Study
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Hae-Sung Nam, So Yeon Ryu, Seong-Woo Choi, Young Hoon Lee, Min-Ho Shin, Jung Ho Yang, Sun-Seog Kweon, Hye-Yeon Kim, and Kyeong Soo Park
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Adult ,Male ,Alcohol Drinking ,Genotype ,Hydrocortisone ,Aldehyde dehydrogenase ,Physiology ,Alcohol ,Polymorphism, Single Nucleotide ,Cortisol ,chemistry.chemical_compound ,Asian People ,Polymorphism (computer science) ,Human Genetics & Genomics ,Mendelian randomization ,Medicine ,Humans ,Genetic Predisposition to Disease ,Association (psychology) ,ALDH2 ,Aged ,biology ,business.industry ,Aldehyde Dehydrogenase, Mitochondrial ,Mendelian Randomization Analysis ,General Medicine ,Middle Aged ,Causality ,chemistry ,biology.protein ,Original Article ,Female ,business ,Alcohol consumption ,hormones, hormone substitutes, and hormone antagonists - Abstract
Background Several studies have reported conflicting results regarding the relationship between alcohol consumption and cortisol levels. However, the causality between alcohol consumption and cortisol levels has not been evaluated. Methods This study examined 8,922 participants from the Dong-gu Study. The aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism was used as an instrumental variable for alcohol consumption. The association between the genetically predicted alcohol consumption and cortisol level was evaluated with Mendelian randomization (MR) using two-stage least squares regression. Results Alcohol consumption was positively associated with the serum cortisol level in both sexes in the observational analysis. In the MR analysis, the genetically predicted alcohol consumption was positively related to the cortisol level in men, with cortisol levels increasing by 0.18 µg/dL per drink per day. However, there was no relationship in women in the MR analysis. Conclusion The predicted alcohol consumption according to the ALDH2 rs671 polymorphism was positively related to the cortisol levels, suggesting a causal relationship between alcohol consumption and cortisol levels., Graphical Abstract
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- 2021
11. Changes in each retinal layer and ellipsoid zone recovery after full-thickness macular hole surgery
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Min-Woo Lee, Young-Hoon Lee, Tae-Yeon Kim, Seung-Kook Baek, and Yong-Yeon Song
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Male ,medicine.medical_specialty ,Visual acuity ,genetic structures ,Science ,Visual Acuity ,Diseases ,Article ,Retina ,03 medical and health sciences ,chemistry.chemical_compound ,Medical research ,0302 clinical medicine ,medicine ,Full-thickness macular hole ,Humans ,Outer nuclear layer ,External limiting membrane ,Ganglion cell layer ,Macular hole ,Multidisciplinary ,business.industry ,Retinal ,Retinal Perforations ,Inner plexiform layer ,medicine.disease ,eye diseases ,Surgery ,medicine.anatomical_structure ,chemistry ,030221 ophthalmology & optometry ,Medicine ,Female ,sense organs ,medicine.symptom ,business ,Tomography, Optical Coherence ,030217 neurology & neurosurgery - Abstract
To analyze the changes in each retinal layer and the recovery of the ellipsoid zone (EZ) after full-thickness macular hole (FTMH) surgery. Patients who underwent surgery for FTMH were included. Spectral-domain optical coherence tomography (SD-OCT) was performed preoperatively and postoperatively at 1, 3, 6, 9, and 12 months. A total of 32 eyes were enrolled. Ganglion cell layer, inner plexiform layer, and inner nuclear layer showed significant reductions over time after surgery (P = 0.020, P = 0.001, and P = 0.001, respectively), but were significantly thicker than those of fellow eyes at 12 months postoperatively. The average recovery duration of the external limiting membrane (ELM), outer nuclear layer (ONL), and EZ was 1.5, 2.1, and 6.1 months, respectively. Baseline best-corrected visual acuity (BCVA) (P = 0.003), minimum linear diameter (MLD) (P = 0.025), recovery of EZ (P = 0.008), and IRL thickness (P
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- 2021
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12. Effects of prolonged type 2 diabetes on changes in peripapillary retinal nerve fiber layer thickness in diabetic eyes without clinical diabetic retinopathy
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Hyung-Bin Lim, Young-Hoon Lee, Min Su Kim, Min-Woo Lee, Kiyup Nam, Gi-Seok Park, and Jung Yeul Kim
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Male ,medicine.medical_specialty ,endocrine system diseases ,Science ,Optic Disk ,Visual Acuity ,Nerve fiber layer ,030209 endocrinology & metabolism ,Pathogenesis ,Type 2 diabetes ,Article ,Retina ,03 medical and health sciences ,chemistry.chemical_compound ,Hba1c level ,Medical research ,Nerve Fibers ,0302 clinical medicine ,Ophthalmology ,medicine ,Humans ,In patient ,Longitudinal Studies ,Aged ,Glycated Hemoglobin ,Diabetic Retinopathy ,Multidisciplinary ,business.industry ,Reduction rate ,Retinal ,Diabetic retinopathy ,Middle Aged ,medicine.disease ,medicine.anatomical_structure ,Diabetes Mellitus, Type 2 ,chemistry ,030221 ophthalmology & optometry ,Medicine ,Female ,business ,Tomography, Optical Coherence - Abstract
To identify the effects of prolonged type 2 diabetes (T2DM) on changes in peripapillary retinal nerve fiber layer (pRNFL) thickness in patients without clinical diabetic retinopathy. Subjects were divided into two groups: controls and patients with T2DM (DM group). After the initial visits, the pRNFL thicknesses were measured three more times at 1-year intervals. Subgroup analyses were performed in patients with T2DM duration ≥ 10 years. The mean pRNFL thickness at each visit was 95.8 ± 8.1, 95.4 ± 8.3, 94.9 ± 8.1, and 94.5 ± 8.3 μm in the control group (P = 0.138) (n = 55); and 93.4 ± 9.1, 92.1 ± 9.3, 90.9 ± 9.3, and 89.5 ± 9.2 μm in the DM group (P P = 0.001) were significant factors associated with pRNFL reduction. In patients with T2DM duration ≥ 10 years, the estimated pRNFL reduction rate was − 1.61 μm/year, and hypertension was a significant factor affecting the pRNFL reduction (P = 0.046). We confirmed rapid pRNFL reduction over time in T2DM, and the reduction rate was higher in patients with T2DM ≥ 10 years. Additionally, BCVA and HbA1c levels were significantly associated with the change in pRNFL thickness in T2DM patients.
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- 2021
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13. Association between alcohol and bone mineral density in a Mendelian randomization study: the Dong-gu study
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Kyeong-Soo Park, Min-Ho Shin, Young-Hoon Lee, Sun-Seog Kweon, Chang Kyun Choi, Hae-Sung Nam, So Yeon Ryu, and Seong-Woo Choi
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musculoskeletal diseases ,Male ,medicine.medical_specialty ,Bone density ,Endocrinology, Diabetes and Metabolism ,Alcohol ,Polymorphism, Single Nucleotide ,chemistry.chemical_compound ,Endocrinology ,Polymorphism (computer science) ,Bone Density ,Internal medicine ,Mendelian randomization ,Medicine ,Humans ,Orthopedics and Sports Medicine ,ALDH2 ,Bone mineral ,Lumbar Vertebrae ,business.industry ,Aldehyde Dehydrogenase, Mitochondrial ,Mendelian Randomization Analysis ,General Medicine ,musculoskeletal system ,Confidence interval ,Causality ,chemistry ,Female ,business - Abstract
Many previous studies have reported a positive relationship between alcohol and bone mineral density (BMD). However, the causality between alcohol and BMD has not been fully evaluated. This study enrolled 8892 participants from the Dong-gu study. Mendelian randomization (MR) using two-stage least-squared regression was used to evaluate the association between the genetically predicted amount of alcohol consumption per day and BMD. The aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphism was used as instrumental variables for alcohol consumption. Age, smoking history, and BMI were adjusted in the multivariate model. Self-reported alcohol consumption was positively related to total hip and lumbar spine BMD in both sexes. In multivariate Mendelian randomization analysis, the genetically predicted amount of alcohol consumption was positively associated with both total hip and lumbar spine BMD in men. Total hip BMD and lumbar spine BMD increased by 0.004 g/cm2 (95% confidence interval [CI] 0.002–0.007) and 0.007 g/cm2 (95% CI 0.004–0.011) with doubling of alcohol consumption. However, in women, genetically predicted alcohol consumption was not significantly associated with BMD. In our MR study, genetically predicted alcohol consumption was positively associated with BMD in men. This result suggests that the association between alcohol consumption and BMD is causal.
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- 2021
14. Long-Term Outcome of Epiretinal Membrane Surgery in Patients with Internal Limiting Membrane Dehiscence
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Il Jung, Min-Woo Lee, Young-Hoon Lee, Yong-Yeon Song, and Seung-Kook Baek
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medicine.medical_specialty ,Visual acuity ,genetic structures ,ERM ,ILM dehiscence ,RNFL schisis ,medicine.medical_treatment ,bare RNFL ,lcsh:Medicine ,Vitrectomy ,Dehiscence ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,In patient ,030304 developmental biology ,0303 health sciences ,business.industry ,Internal limiting membrane ,lcsh:R ,Retinal ,General Medicine ,medicine.disease ,Layer thickness ,eye diseases ,Surgery ,chemistry ,030221 ophthalmology & optometry ,sense organs ,Epiretinal membrane ,medicine.symptom ,business - Abstract
Purpose: To identify the effect of internal limiting membrane (ILM) dehiscence on surgical outcomes in eyes that have undergone epiretinal membrane (ERM) removal. Methods: Consecutive eyes with performed vitrectomy for ERM removal were included. Subjects were divided into two groups: patients with ILM dehiscence (group 1) and without ILM dehiscence (group 2). The best-corrected visual acuity (BCVA) and retinal layer thickness before and after surgery were compared between the two groups. Results: A total of 86 eyes were enrolled. Forty-six eyes (53.5%) showed ILM dehiscence before surgery. The baseline BCVAs were 0.46 ± 0.29 and 0.45 ± 0.25 in groups 1 and 2, respectively (p = 0.801). The BCVAs at 3, 6, and 12 months after surgery differed significantly between the two groups. The subfoveal thickness and inner retinal layer thickness (IRLT) of group 1 vs. 2 were 507.4 ± 80.0 vs. 417.6 ± 63.6 μm, and 270.2 ± 74.3 vs. 182.6 ± 60.4 μm, respectively (both p < 0.001). These differences between the groups remained significant until 12 months after surgery. In multivariate analyses, the location of ILM dehiscence (B = −0.105, p = 0.034) and final IRLT (B = 0.001, p = 0.046) were significant factors affecting the final BCVA. Conclusions: ILM dehiscence is a relatively common finding and associated with preoperative and postoperative increased IRLT, which results in worse surgical outcomes compared to the absence of ILM dehiscence in patients with ERM. Additionally, the final BCVA was significantly affected by its location and final IRLT in patients with ILM dehiscence.
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- 2020
15. Effects of Prolonged Type 2 Diabetes on the Inner Retinal Layer and Macular Microvasculature: An Optical Coherence Tomography Angiography Study
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Hyung-Bin Lim, Cheon-Kuk Ryu, Min-Woo Lee, Woo-Hyuk Lee, Tae-Yeon Kim, Young-Hoon Lee, and Jung Yeul Kim
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medicine.medical_specialty ,Visual acuity ,endocrine system diseases ,genetic structures ,lcsh:Medicine ,030209 endocrinology & metabolism ,Type 2 diabetes ,optical coherence tomography angiography ,Article ,Microcirculation ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Bayesian multivariate linear regression ,Diabetes mellitus ,Ophthalmology ,vessel density ,medicine ,ganglion cell-inner plexiform layer ,diabetes ,business.industry ,lcsh:R ,nutritional and metabolic diseases ,Retinal ,General Medicine ,Diabetic retinopathy ,medicine.disease ,eye diseases ,Ganglion ,medicine.anatomical_structure ,chemistry ,030221 ophthalmology & optometry ,sense organs ,medicine.symptom ,business - Abstract
Purpose: To identify the effects of prolonged type 2 diabetes (T2DM) on macular microcirculation and the inner retinal layer in diabetic eyes without clinical diabetic retinopathy (DR). Methods: 97, 92, and 57 eyes in the control, patients with T2DM <, 10 years (DM group one), and patients with T2DM &ge, 10 years (DM group two) were enrolled. The ganglion cell-inner plexiform layer (GC-IPL) thickness and superficial vessel density (VD) were compared. Linear regression analyses were performed to identify factors associated with VD in T2DM patients. Results: GC-IPL thicknesses in the control, DM group one, and DM group two were 84.58 ±, 0.89, 83.49 ±, 0.70, and 79.04 ±, 0.96 &mu, m, respectively (p <, 0.001). The VDs of the full area were 20.32 ±, 0.15, 19.46 ±, 0.17, and 18.46 ±, 0.23 mm&minus, 1 (p <, 0.001). Post-hoc analyses revealed that the VDs of the full area was significantly different in the control vs. DM group one (p = 0.001), control vs. DM group two (p <, 0.001), and DM group one vs. DM group two (p = 0.001). Multivariate linear regression analyses revealed that DM duration (p = 0.037), visual acuity (p = 0.013), and GC-IPL thickness (p <, 0.001) were significantly associated with the VD of T2DM patients. Conclusions: We confirmed GC-IPL thinning and decreased superficial VD in the macular areas using OCTA in T2DM patients. Patients with T2DM &ge, 10 years exhibited significantly more severe macular microcirculation impairment compared to patients with T2DM <, 10 years and normal controls.
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- 2020
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16. Preparation of nickel selenide by pulsed-voltage electrodeposition and its application as a highly-efficient electrocatalyst at counter electrodes of quantum-dot sensitized solar cells
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E. Vijayakumar, Yong-Han Yun, Kwang-Soon Ahn, Vu Hong Vinh Quy, Hyun-Chul Kim, Young-Hoon Lee, and Soon-Hyung Kang
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Materials science ,Nanoporous ,General Chemical Engineering ,chemistry.chemical_element ,Nickel selenide ,02 engineering and technology ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Tin oxide ,Electrocatalyst ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Nickel ,chemistry ,Chemical engineering ,Quantum dot ,Electrochemistry ,Thin film ,0210 nano-technology - Abstract
We fabricate the nickel selenide thin films on fluorine-doped tin oxide conducting glass subtract using pulsed-voltage electrodeposition method for counter electrodes in quantum-dot-sensitized solar cells. The novelty of this work is nickel selenides are prepared by PVE significantly differs from the traditional continuous-voltage electrodeposition in morphology, compositions, and electrocatalytic activities. In general, NiSe2-PVE films consist of clusters with crystalline NiSe2 nanoparticles which remain nanoporous because application of anodic bias during pulsed electrodeposition enables diffusion layer of H2SeO3 recover from the deposition. The subsequent short cathodic bias not only facilitates new nucleation of nickel selenide but also hinders grain growth. In contrast, Ni3Se2-CVE film consists dense larger Ni3Se2 grains with surface microcracks attributed to continuous grain growth and accumulated film stress. Hence, NiSe2-PVE enhances electrocatalytic activity in polysulfide electrolyte in an effective manner when compare to Ni3Se2-CVE, owing to significantly more electrocatalytic active sites and enhance charge and mass transports. As an outcome, QDSSC with NiSe2-PVE CE achieve significantly higher power conversion efficiency of 4.46% than those of cells with Pt (2.62%) and Ni3Se2-CVE (2.63%) CEs. Furthermore, electrochemical stability in polysulfide electrolyte medium is reasonably high.
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- 2019
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17. Cystatin C-based estimated GFR and albuminuria are independently associated with all-cause and CVD mortality in Korean population: The Dong-gu Study
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Min-Ho Shin, Sun-Seog Kweon, Young-Hoon Lee, Kyeong-Soo Park, Hae-Sung Nam, So Yeon Ryu, Hye-Yeon Kim, and Seong-Woo Choi
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Male ,medicine.medical_specialty ,Waist ,Renal function ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Republic of Korea ,Medicine ,Albuminuria ,Humans ,030212 general & internal medicine ,Cystatin C ,Aged ,Aged, 80 and over ,Creatinine ,030219 obstetrics & reproductive medicine ,biology ,business.industry ,Proportional hazards model ,Obstetrics and Gynecology ,Middle Aged ,Confidence interval ,Blood pressure ,chemistry ,Cardiovascular Diseases ,biology.protein ,Female ,medicine.symptom ,business ,Glomerular Filtration Rate - Abstract
Objective To assess the associations among the estimated glomerular filtration rate (eGFR), albumin to creatinine ratio (ACR), and all-cause and CVD mortality rate and to compare the performances of eGFRMDRD, eGFRCKD-EPI, and eGFRcys using receiver operating characteristic (ROC) analysis in Korean adults aged ≥ 50 years. Methods Of the 9,260 subjects who participated in the baseline survey of a prospective longitudinal study conducted in Korea, 9,009 (men: 3,574 (39.7%); women: 5,435 (60.3%)) were included in this analysis after the exclusion of 217 subjects with missing eGFR and 34 subjects with missing ACR data. Main outcome measure The associations of eGFR and ACR with all-cause and CVD mortality were investigated using Cox proportional hazards models that included sex, age, waist circumference, smoking, alcohol intake, degree of physical activity, hypertension, diabetes, systolic blood pressure, log-HbA1c, total cholesterol, log-triglyceride, log-HDL and log-ACR or eGFR. Results After adjustment for covariates, independent associations were found between all-cause mortality and the eGFRcys (mL/min per 1.73 m2) [HR 1.23, 95% confidence interval (CI) 1.05–1.43 for 60–89 vs. ≥ 90; HR 1.87, 95% CI 1.49–2.34 for 45–59 vs. ≥ 90; HR 2.38, 95% CI 1.77–3.20 for 30–44 vs. ≥ 90; HR 2.82, 95% CI 1.89–4.23 for Conclusion The eGFRcys and ACR were associated independently with all-cause and CVD mortality after adjustment for covariates, including the eGFRcys and ACR. In addition, the ROC-plot AUC for all-cause mortality was greater for the eGFRcys than for the eGFRMDRD and eGFRCKD-EPI in Korean adults aged ≥ 50 years.
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- 2020
18. Habitual consumption of soy protein and isoflavones and risk of metabolic syndrome in adults ≥ 40 years old: a prospective analysis of the Korean Multi-Rural Communities Cohort Study (MRCohort)
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Min-Ho Shin, Mi Kyung Kim, Hye Won Woo, Young-Hoon Lee, Bo Youl Choi, and Dong Hoon Shin
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Male ,Rural Population ,0301 basic medicine ,Inverse Association ,Medicine (miscellaneous) ,Physiology ,030209 endocrinology & metabolism ,Cohort Studies ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Risk Factors ,Surveys and Questionnaires ,Republic of Korea ,Humans ,Medicine ,Prospective Studies ,Soy protein ,Abdominal obesity ,Metabolic Syndrome ,030109 nutrition & dietetics ,Nutrition and Dietetics ,Triglyceride ,business.industry ,Incidence (epidemiology) ,Middle Aged ,Isoflavones ,medicine.disease ,Diet ,chemistry ,Soybean Proteins ,Female ,Metabolic syndrome ,medicine.symptom ,business ,Cohort study - Abstract
Although considerable attention has been paid to the potential benefits of soy protein and isoflavones for preventing metabolic syndrome (MetS) and its components, findings linking habitual consumption of these factors to MetS are limited. This study aimed to evaluate the association of MetS incidence with habitual intake of soy protein/isoflavones among Korean men and women aged ≥ 40 years old who did not have MetS at baseline (n = 5509; 2204 men and 3305 women). Dietary intake of soy protein/isoflavones at baseline and average consumption during follow-up were used. A significant inverse association between dietary intake and incidence of MetS was found in women (incidence rate ratios, IRR = 0.60, 95% CI = 0.46–0.78, P for trend = 0.0094 for the highest quintile of average soy protein intake compared with the lowest quintile; IRR = 0.57, 95% CI = 0.44–0.74, P for trend = 0.0048 for the highest quintile of average isoflavones intake compared with the lowest quintile). A tendency towards an inverse association was also found in men, although it was not significant for the highest quintile (IRR = 0.80, 95% CI = 0.58–1.11, P for trend = 0.9759, comparing the lowest to the highest quintile of average soy protein intake; IRR = 0.73, 95% CI = 0.53–1.01, P for trend = 0.8956, comparing the lowest to the highest quintile of average isoflavones intake). In terms of individual abnormalities, a significant inverse association was found between soy protein and isoflavones and the incidence of low–high-density lipoprotein cholesterol in both men and women. Abdominal obesity and elevated blood pressure were inversely related to soy protein/isoflavones only in women, and an inverse association of elevated triglyceride appeared only in men. Our findings suggest that habitual intake of soy protein and isoflavones is inversely associated with the risk of MetS and its components. There is likely to be a reverse J-shaped association of average intake with MetS.
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- 2018
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19. A Study on the Development of Poly‐Urea for Porcelain Restoration
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Seung-Jun Oh, Young-Hoon Lee, Won-Sik Han, and Koang-Chul Wi
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chemistry.chemical_compound ,Materials science ,060102 archaeology ,chemistry ,010401 analytical chemistry ,Urea ,0601 history and archaeology ,06 humanities and the arts ,01 natural sciences ,0104 chemical sciences ,Nuclear chemistry - Published
- 2018
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20. Rational design of time-resolved turn-on fluorescence sensors: exploiting delayed fluorescence for hydrogen peroxide sensing
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Saibal Jana, Young Hoon Lee, Heechai Lee, Min Hyung Lee, and Sang Uck Lee
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Metals and Alloys ,Rational design ,Oxide ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,Acceptor ,Fluorescence ,Catalysis ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Turn (biochemistry) ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Ceramics and Composites ,Luminophore ,0210 nano-technology ,Hydrogen peroxide ,Phosphine - Abstract
Weakly emissive phosphine compounds, which contain a carbazolyl donor-triarylboryl acceptor luminophore, become strongly delayed fluorescent upon changes to their oxide forms. Time-gated acquisition of the fluorescence signals of phosphine in the presence of H2O2 and a competitive fluorescence dye allow for detection of H2O2 with elimination of short-lived fluorescence noise.
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- 2018
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21. Parathyroid Hormone Levels Are Independently Associated with eGFR and Albuminuria: The Dong-gu Study
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Seong-Woo Choi, Young-Hoon Lee, Hae-Sung Nam, So Yeon Ryu, Kyeong-Soo Park, Min-Ho Shin, Sun A Kim, Sun-Seog Kweon, and Jin-Su Choi
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Adult ,Male ,medicine.medical_specialty ,Medicine (miscellaneous) ,Renal function ,Parathyroid hormone ,030209 endocrinology & metabolism ,030204 cardiovascular system & hematology ,Body Mass Index ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Diabetes mellitus ,Internal medicine ,Republic of Korea ,medicine ,Vitamin D and neurology ,Albuminuria ,Humans ,Prospective Studies ,Vitamin D ,Exercise ,Serum Albumin ,Triglycerides ,Aged ,Creatinine ,Nutrition and Dietetics ,Triglyceride ,Cholesterol ,business.industry ,Middle Aged ,medicine.disease ,Endocrinology ,chemistry ,Parathyroid Hormone ,Female ,Waist Circumference ,medicine.symptom ,business ,Glomerular Filtration Rate - Abstract
Increased parathyroid hormone (PTH) was associated with cardiovascular mortality and morbidity in CKD patients. Our aim was to investigate the associations among estimated glomerular filtration rate (eGFR), albumin/creatinine ratio (ACR) and PTH independent of 25-hydroxyvitamin D (25(OH)D). This study included 9,162 individuals who completed the baseline survey of the Dong-gu Study, which was conducted in Korea from 2007 to 2010. The eGFR, ACR, PTH and 25(OH)D were measured in participants who met the detailed inclusion criteria. After being adjusting for covariates (sex, age, waist circumference, smoking, alcohol intake, physical activity, hypertension medications, diabetes medication, total cholesterol, triglyceride, HDL cholesterol) and log-ACR, the PTH value stratified by 25(OH)D level significantly decreased with increasing eGFR levels in each 25(OH)D stratum. Moreover, after adjustment for the same covariates and log-eGFR, the PTH value stratified by 25(OH)D level significantly increased with increasing ACR levels in each 25(OH)D stratum. In conclusion, the PTH values significantly decreased with increasing eGFR levels and increased with increasing ACR levels independently of 25(OH)D in an adult Korean population ≥50 y of age.
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- 2018
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22. Photophysical and Lewis acidic properties of triarylboranes with meta-substituted 2-R-o-carboranes
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Young Hoon Lee, Hyung Dong Lee, Junseong Lee, Ji Yeon Ryu, and Min Hyung Lee
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chemistry.chemical_classification ,Steric effects ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Inorganic chemistry ,Crystal structure ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Medicinal chemistry ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Materials Chemistry ,Titration ,Lewis acids and bases ,Physical and Theoretical Chemistry ,Absorption (chemistry) ,Fluoride ,Inductive effect ,Alkyl - Abstract
Triarylboranes incorporating meta-substituted 2-R-o-carboranes (R = H, Me, iBu, Ph, 4-CF3C6F4) were prepared to investigate the effects of the meta-2-R-o-carborane on Lewis acidity. X-ray crystal structures revealed that the carboranyl C C bond distances increased with increasing steric and electron-withdrawing effects of the 2-R group. UV/Vis absorption titrations with fluoride ions showed high binding constants (K > 107 M−1 in THF and K = 3.9–6.6 × 103 M−1 in THF/H2O (9:1 vol)). Fluoride ion affinity was greater for the 2-aryl (4-CF3C6F4)-substituted triarylborane than 2-H and -alkyl (Me)-substituted triarylboranes, which was supported by anodic shifts in the reduction potentials of 2-aryl-o-carborane-substituted triarylboranes. Comparison of fluoride binding constants and reduction potentials of meta- and para-substituted triarylboranes indicated slightly lower Lewis acidity of meta-substituted triarylboranes. In contrast to para-substituted triarylboranes, the Lewis acidity of meta-substituted triarylboranes is likely to be primarily enhanced by the inductive effect of the 2-R-o-carborane.
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- 2017
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23. Anion-dependent interpenetration in lattices of Ag(I) complexes of a divergent quaterpyridine-donor ligand
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Young Hoon Lee, Jack Harrowfield, Yang Kim, Jong Won Shin, and Shinya Hayami
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chemistry.chemical_classification ,Coordination polymer ,Stereochemistry ,02 engineering and technology ,Polymer ,Crystal structure ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Ion ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,chemistry ,Lattice (order) ,Materials Chemistry ,Physical and Theoretical Chemistry ,0210 nano-technology ,Benzene - Abstract
Crystal structure determinations for the divergent quaterpyridine-type ligand bis-1,4-(di-4-pyridylaminomethyl)benzene, dpab, and its complexes with silver(I) trifluoroacetate and nitrate have revealed the operation of different weak interactions within the lattices. Coordination of four pyridyl-N donors to Ag(I) in the trifluoroacetate results in a 3-dimensional coordination polymer with the uncoordinated anions held within the cavities created by that polymer. In the nitrate, only two pyridyl-N donors are bound to each of the two inequivalent Ag(I) centres and the lattice contains two interpenetrating coordination polymers linked by CH⋯O interactions involving the coordinated anions.
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- 2017
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24. Effect Modification of Acetaldehyde Dehydrogenase 2 rs671 Polymorphism on the Association between Alcohol Intake and Blood Pressure: the Dong-gu Study
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Young Hoon Lee, Sun-Seog Kweon, Chang Kyun Choi, Min-Ho Shin, Hye-Yeon Kim, Seong-Woo Choi, Hae-Sung Nam, So Yeon Ryu, and Kyeong Soo Park
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Male ,Alcohol Drinking ,Genotype ,Physiology ,Blood Pressure ,Alcohol ,Preventive & Social Medicine ,Logistic regression ,Cohort Studies ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Asian People ,Gene Frequency ,Risk Factors ,Bayesian multivariate linear regression ,Republic of Korea ,Odds Ratio ,Humans ,Medicine ,030212 general & internal medicine ,Polymorphism ,Life Style ,Alleles ,ALDH2 ,Polymorphism, Genetic ,business.industry ,Aldehyde Dehydrogenase, Mitochondrial ,General Medicine ,Odds ratio ,Middle Aged ,Confidence interval ,Blood pressure ,chemistry ,Hypertension ,Female ,Original Article ,business ,Cohort study - Abstract
Background Elevated blood pressure is a major preventable cause of cardiovascular diseases. Alcohol consumption is a well-known risk factor of elevated blood pressure. The aldehyde dehydrogenase 2 (ALDH2) polymorphism is common in Eastern Asians, and inactive ALDH2 genotypes are associated with both avoiding alcohol consumption and aldehyde accumulation. Therefore, this study assessed the associations between alcohol consumption and hypertension and blood pressure according to the ALDH2 genotypes. Methods This study consists of 8,526 participants in the Dong-gu Study. Multivariate logistic regression was used to calculate the odds ratio (OR) according to alcohol consumption after stratifying by gender and ALDH2 genotypes. Multivariate linear regression was performed to estimate the systolic blood pressure (SBP) and diastolic blood pressure (DBP) according to the amount of alcohol consumed. Results In men, alcohol consumption was positively associated with both SBP and DBP in active ALDH2 carriers, but not in inactive ALDH2 carriers. In active ALDH2 carriers, compared to non-drinkers, the OR of hypertension was 1.16 (95% confidence interval [CI], 0.91–1.49) for < 1 drink/day, and 1.44 (95% CI, 1.15–1.80) for ≥ 1 drink/day in men. With each 1 drink/day increase, SBP and DBP increased by 3 and 1 mmHg in men, respectively. There was no significant association between ALDH2 genotypes and hypertension and blood pressure in women. Conclusion ALDH2 genotype modified the association between alcohol consumption and blood pressure in men. There was a positive relationship between alcohol consumption and blood pressure in active ALDH2 carriers, but no significant relationship in inactive ALDH2 carriers., Graphical Abstract
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- 2020
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25. Association of high myopia with peripapillary retinal nerve fiber layer in patients with hypertension
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Jung Yeul Kim, Hyung-Moon Koo, Min-Woo Lee, Hyung-Bin Lim, and Young-Hoon Lee
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Male ,Eye Diseases ,Visual Acuity ,Nerve fiber layer ,Glaucoma ,Blood Pressure ,Comorbidity ,Vascular Medicine ,chemistry.chemical_compound ,Nerve Fibers ,Mathematical and Statistical Techniques ,Medical Conditions ,Animal Cells ,Ischemia ,Bayesian multivariate linear regression ,Medicine and Health Sciences ,Myopia ,Medicine ,Visual Impairments ,Neurons ,Multidisciplinary ,Statistics ,Confounding ,Middle Aged ,medicine.anatomical_structure ,Hypertension ,Physical Sciences ,Regression Analysis ,Female ,Analysis of variance ,Anatomy ,Cellular Types ,Tomography, Optical Coherence ,Research Article ,medicine.medical_specialty ,Science ,Linear Regression Analysis ,Research and Analysis Methods ,Retina ,Ocular System ,Ophthalmology ,Republic of Korea ,Linear regression ,Humans ,cardiovascular diseases ,Statistical Methods ,Intraocular Pressure ,Retrospective Studies ,business.industry ,Biology and Life Sciences ,Retinal ,Cell Biology ,medicine.disease ,Cross-Sectional Studies ,Blood pressure ,chemistry ,Cellular Neuroscience ,Case-Control Studies ,Eyes ,business ,Head ,Mathematics ,Neuroscience - Abstract
Purpose To identify the impacts of hypertension (HTN), high myopia, and the combination thereof on peripapillary retinal nerve fiber layer (pRNFL) thickness. Methods All subjects were divided into four groups: control (group 1); patients with HTN without high myopia (group 2); patients with high myopia without HTN (group 3); and patients with both HTN and high myopia (group 4). The pRNFL thicknesses were compared using a one-way analysis of variance. Univariate and multivariate linear regression analyses were used to identify factors affecting pRNFL thickness in subjects with and without HTN. Results The mean pRNFL thicknesses were 93.9±8.8, 88.7±6.8, 86.4±8.1, and 82.5±9.6 μm in group 1, 2, 3, and 4, respectively, and differed significantly (P Conclusions High myopia and HTN affected pRNFL reduction and a combination of the 2 diseases exacerbated pRNFL damage. This could be a confounding factor in interpreting pRNFL thickness in patients with ophthalmic diseases affecting the pRNFL thickness when combined with the 2 diseases.
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- 2021
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26. Impact of boryl acceptors in para-acridine-appended triarylboron emitters on blue thermally activated delayed fluorescence OLEDs
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Taehwan Lee, Donggyun Lee, Junseung Lee, Young Hoon Lee, Jaehoon Jung, Seunghyup Yoo, and Min Hyung Lee
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Chemistry ,Process Chemistry and Technology ,General Chemical Engineering ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Ring (chemistry) ,Photochemistry ,01 natural sciences ,Fluorescence ,0104 chemical sciences ,chemistry.chemical_compound ,Phenylene ,Acridine ,OLED ,Moiety ,0210 nano-technology ,Linker - Abstract
Two pairs of para-donor-appended triarylboron compounds that are derived from 9,9-dialkylacridine (9,9-dimethylacridine (DMAC) or 9,9-diphenylacridine (DPAC)) donors and boryl (9-boraanthryl (BA) or dimesitylboryl (BMes2)) acceptors are prepared and characterized. X-ray diffraction studies reveal that the BA ring is nearly orthogonal to the phenylene linker, whereas the BMes2 moiety is tilted by ca. 60°. The BA-containing compounds exhibit blue thermally activated delayed fluorescence (TADF) in both the solution and film states. In contrast, BMes2-containing compounds display normal blue fluorescence in solution, while TADF is induced in their films. The small ΔEST values (
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- 2021
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27. Peripapillary Retinal Nerve Fiber Layer and Microvasculature in Prolonged Type 2 Diabetes Patients Without Clinical Diabetic Retinopathy
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Young-Hoon Lee, Min-Woo Lee, Cheon-Kuk Ryu, Jung Yeul Kim, Woo-Hyuk Lee, and Yong Min Lee
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Male ,Retinal Ganglion Cells ,medicine.medical_specialty ,Visual acuity ,endocrine system diseases ,Optic Disk ,Visual Acuity ,Nerve fiber layer ,030209 endocrinology & metabolism ,Type 2 diabetes ,optical coherence tomography angiography ,Retina ,03 medical and health sciences ,chemistry.chemical_compound ,Nerve Fibers ,0302 clinical medicine ,vessel density ,Ophthalmology ,medicine ,Humans ,In patient ,Retrospective Studies ,Diabetic Retinopathy ,diabetes ,business.industry ,Retinal Vessels ,retinal nerve fiber layer ,Retinal ,Diabetic retinopathy ,Axial length ,Middle Aged ,medicine.disease ,Cross-Sectional Studies ,medicine.anatomical_structure ,Diabetes Mellitus, Type 2 ,chemistry ,Microvessels ,030221 ophthalmology & optometry ,Female ,Erratum ,medicine.symptom ,business ,Perfusion ,Tomography, Optical Coherence - Abstract
Purpose The purpose of this study to identify the effects of prolonged type 2 diabetes (T2DM) on the peripapillary retinal nerve fiber layer (pRNFL) and peripapillary microvasculature in patients with prolonged T2DM without clinical diabetic retinopathy (DR). Methods Subjects were divided into 3 groups: controls (control group; 153 eyes), patients with T2DM < 10 years (DM group 1; 136 eyes), and patients with T2DM ≥ 10 years (DM group 2; 74 eyes). The pRNFL thickness and peripapillary superficial vessel density (VD) were compared. Linear regression analyses were performed to identify factors associated with peripapillary VD in patients with T2DM. Results The mean pRNFL thicknesses of the control group, DM group 1, and DM group 2 were 96.0 ± 7.9, 94.5 ± 0.9, and 92.2 ± 8.2 µm, respectively (P < 0.001). The VDs were 18.24 ± 0.62, 17.60 ± 1.47, and 17.15 ± 1.38 mm−1 in the control group, DM group 1, and DM group 2, respectively (P < 0.001). In multivariate linear regression analyses, visual acuity (B = −2.460, P = 0.001), axial length (B = −0.169, P = 0.008), T2DM duration (B = −0.056, P < 0.001), and pRNFL (B = 0.024, P = 0.001) were significant factors affecting the peripapillary VD in patients with T2DM. Conclusions Patients with T2DM without clinical DR showed thinner pRNFL and lower peripapillary VD and perfusion density (PD) compared with normal controls, and such damage was more severe in patients with T2DM ≥ 10 years. Additionally, peripapillary VD was significantly associated with best-corrected visual acuity (BCVA), axial length, T2DM duration, and pRNFL thickness in patients with T2DM.
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- 2021
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28. Enhanced electrocatalytic activity and electrochemical stability of Cu2S/PbS counter electrode for quantum-dot-sensitized solar cells
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Young-Hoon Lee, Jeong-Hyun Park, Kwang-Soon Ahn, John Anthuvan Rajesh, and In-Rok Jo
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Auxiliary electrode ,Materials science ,Passivation ,General Physics and Astronomy ,Nanoparticle ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Copper sulfide ,chemistry ,Chemical engineering ,Electrode ,Lead sulfide ,0210 nano-technology - Abstract
A new strategy has been successfully developed for highly efficient copper sulfide/lead sulfide (Cu2S/PbS) counter electrodes (CEs) for quantum-dot-sensitized solar cells (QDSSCs). PbS nanoparticles were grown by successive ionic layer adsorption and reaction (SILAR) technique for various cycles (from 1 to 4) on electrochemically deposited Cu2S nanosheets. All the Cu2S and Cu2S/PbS CEs showed petal-like morphology and nanosized PbS nanoparticles were deposited over the Cu2S nanosheets. All FTO/Cu2S/PbS CEs exhibited superior electrocatalytic activity than FTO/Pt and FTO/Cu2S CEs. In particular, QDSSCs with FTO/Cu2S/PbS CE (3 SILAR cycles) exhibited extremely high short-circuit current density (18.08 mA cm−2) and fill factor (53.55%), resulting in a significantly enhanced power conversion efficiency as high as 5.28%. This is because the FTO/Cu2S/PbS CE not only exhibits the cascaded, stepwise energy level configuration, which enhances the fast charge transportation, but also serves as a blocking layer to prevent electrons from returning from the electrolyte to the Cu2S. Furthermore, FTO/Cu2S/PbS exhibited excellent electrochemical stability unlike FTO/Cu2S, owing to the passivation of PbS.
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- 2020
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29. Color-switchable electrochromic Co(OH)2/Ni(OH)2 nanofilms with ultrafast kinetics for multifunctional smart windows
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In-Rok Jo, Jiho Kang, Jin Soo Kang, Yung-Eun Sung, Jeong-Hyun Park, Young-Hoon Lee, and Kwang-Soon Ahn
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Supercapacitor ,Materials science ,Renewable Energy, Sustainability and the Environment ,Kinetics ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochromic devices ,01 natural sciences ,Energy storage ,0104 chemical sciences ,law.invention ,Capacitor ,chemistry.chemical_compound ,chemistry ,law ,Electrochromism ,Hydroxide ,General Materials Science ,Electrical and Electronic Engineering ,0210 nano-technology ,Order of magnitude - Abstract
Electrochromic devices have received great attention due to the steep growth of smart window markets and demands from various emerging fields. Recently, elaborately designed materials not only enhanced coloring/bleaching performances but also provided additional functionality, energy storage, since electrochromism relies on capture and release of ions. Meanwhile, given that electrochromic devices are mostly targeted for large-scale applications such as smart windows, there are still significant needs for further advances, especially in terms of reliability and simplicity of materials and their manufacturing processes. In this study, double-layer hydroxide films are reported as energy-storable electrochromic materials with ultrafast transition kinetics. Core/shell-like Co(OH)2/Ni(OH)2 films produced within a minute of electrodepositions have capabilities for multiple color changes and show extremely fast optical responses that are comparable to state-of-the-arts. In addition, the electrodeposited hydroxide films manifest high capacitance and rate capabilities when applied as capacitors, with electrochromic kinetics an order of magnitude higher than those with similar level of capacities for energy storage.
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- 2020
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30. 25-Hydroxyvitamin D Is Associated with Kidney Function: The Dong-gu Study
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Hae-Sung Nam, Sun A Kim, Min-Ho Shin, So Yeon Ryu, Young-Hoon Lee, Kyeong-Soo Park, Seong-Woo Choi, and Sun-Seog Kweon
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Male ,medicine.medical_specialty ,Medicine (miscellaneous) ,Renal function ,Kidney ,chemistry.chemical_compound ,Internal medicine ,Republic of Korea ,medicine ,Vitamin D and neurology ,Albuminuria ,Humans ,Renal Insufficiency, Chronic ,Vitamin D ,Aged ,Creatinine ,Nutrition and Dietetics ,business.industry ,Albumin ,Middle Aged ,Vitamin D Deficiency ,Endocrinology ,chemistry ,Female ,medicine.symptom ,Urine sample ,business ,Glomerular Filtration Rate - Abstract
Although the kidneys play a leading part in the biosynthesis of vitamin D, there is no consensus regarding the relationship of the vitamin D concentration with kidney function. Thus, we aimed to estimate the correlation among 25-hydroxyvitamin D (25(OH)D), estimated glomerular filtration rate (eGFR), and albumin/creatinine ratio (ACR) in participants aged ≥50 y in Korea. This study consisted of 9,166 people who participated in a basic survey of the Dong-gu Study. Following an overnight fast, the blood and urine sample were assessed. The serum 25(OH)D, eGFR, ACR of each subject were measured. When adjusting for covariates and log-transformed ACR (Model III), the lower eGFR value was significantly associated with increasing 25(OH)D levels (
- Published
- 2019
31. Risk factors for breakthrough vitreous hemorrhage after intravitreal anti-VEGF injection in age-related macular degeneration with submacular hemorrhage
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Jae-Yun Sung, Young-Joon Jo, Min Sagong, Jung Yeul Kim, Young-Hoon Lee, and Yong-Il Shin
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Male ,Vascular Endothelial Growth Factor A ,0301 basic medicine ,medicine.medical_specialty ,medicine.drug_class ,lcsh:Medicine ,Angiogenesis Inhibitors ,complex mixtures ,Article ,Macular Degeneration ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Ophthalmology ,medicine ,Humans ,lcsh:Science ,Aged ,Aged, 80 and over ,Anti vegf ,Multidisciplinary ,business.industry ,Incidence ,Incidence (epidemiology) ,lcsh:R ,Anticoagulant ,Anticoagulants ,Retinal Hemorrhage ,Retinal ,Odds ratio ,Middle Aged ,Macular degeneration ,medicine.disease ,Injection Site Reaction ,Vitreous Hemorrhage ,Treatment Outcome ,030104 developmental biology ,Choroidal neovascularization ,chemistry ,Intravitreal Injections ,Vitreous hemorrhage ,030221 ophthalmology & optometry ,lcsh:Q ,Female ,medicine.symptom ,business ,Follow-Up Studies - Abstract
To investigate the risk factors for breakthrough vitreous hemorrhage (VH) after intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection in age-related macular degeneration (AMD) accompanied by submacular hemorrhage (SMH). We retrospectively reviewed the medical records of patients diagnosed with AMD combined with SMH, and enrolled 31 patients. We formed an age- and sex-matched control group of patients with submacular hemorrhage who did not develop breakthrough VH after intravitreal injection during 6 month follow-up. The mean patient age was 70.8 ± 10.3 years in the breakthrough VH group. Of the 31 patients, 8 were diagnosed with choroidal neovascularization (CNV), 22 with polypoidal choroidal vasculopathy (PCV), and 1 with retinal angiomatous proliferation (RAP). PCV was associated with a significantly higher incidence of VH (odds ratio, 35.01; p = 0.001). The size of the SMH was 22.7 ± 12.4 disc areas (DAs) in the breakthrough VH group and 5.4 ± 6.9 DAs in the control group, and was thus significantly related to the development of VH (p p = 0.014). There was no significant difference between the types of anti-VEGF agents. When taking anticoagulant medications, a SMH of large diameter, and PCV subtype were risk factors for breakthrough VH after anti-VEGF injection.
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- 2018
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32. Optical coherence tomography automated layer segmentation of macula after retinal detachment repair
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Young Hoon Lee and Kyu Jin Han
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Photoreceptors ,Male ,Fovea Centralis ,Visual acuity ,Sensory Receptors ,genetic structures ,Vision ,medicine.medical_treatment ,Visual Acuity ,lcsh:Medicine ,Social Sciences ,Vitrectomy ,Retinal Pigment Epithelium ,Diagnostic Radiology ,chemistry.chemical_compound ,0302 clinical medicine ,Animal Cells ,Medicine and Health Sciences ,Psychology ,Macula Lutea ,Postoperative Period ,lcsh:Science ,Tomography ,Neurons ,Multidisciplinary ,Radiology and Imaging ,Ophthalmic Procedures ,Retinal detachment ,Middle Aged ,medicine.anatomical_structure ,Retinal Disorders ,Sensory Perception ,Female ,medicine.symptom ,Anatomy ,Cellular Types ,Tomography, Optical Coherence ,Research Article ,Signal Transduction ,medicine.medical_specialty ,Imaging Techniques ,Ocular Anatomy ,Outer plexiform layer ,Surgical and Invasive Medical Procedures ,Research and Analysis Methods ,Retina ,03 medical and health sciences ,Ocular System ,Diagnostic Medicine ,Ophthalmology ,medicine ,Humans ,Outer nuclear layer ,Aged ,Retinal pigment epithelium ,business.industry ,lcsh:R ,Retinal Detachment ,Biology and Life Sciences ,Afferent Neurons ,Retinal ,Cell Biology ,medicine.disease ,eye diseases ,chemistry ,Surgical Repair ,Cellular Neuroscience ,030221 ophthalmology & optometry ,Eyes ,lcsh:Q ,sense organs ,business ,Head ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Purpose To investigate the thickness of retinal layers and association with final visual acuity using spectral-domain optical coherence tomography (SD-OCT) in macular area of macula-off rhegmatogenous retinal detachment (RRD) patients after a successful macular re-attachment. Methods In retrospective study, a total 24 eyes with macula-off RRD were enrolled. All patients underwent vitrectomy to repair RRD. Outer plexiform layer (OPL), outer nuclear layer (ONL), photoreceptor layer (PR), retinal pigment epithelium (RPE) thicknesses were measured by the Spectralis (Heidelberg Engineering, Heidelberg, Germany) SD-OCT with automated segmentation software. The relationship between the thicknesses of each retinal layer and postoperative logarithm of the minimum angle of resolution scale (LogMAR) visual acuity was analyzed. Results OPL and RPE thicknesses were not significantly different between the retinal detachment eyes and fellow eyes (P = 0.839, 0.999, respectively). The ONL and photoreceptor thickness were significantly thinner in the retinal detachment eyes (P
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- 2018
33. Homoleptic Tris-Cyclometalated Iridium Complexes with Substituted o-Carboranes: Green Phosphorescent Emitters for Highly Efficient Solution-Processed Organic Light-Emitting Diodes
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Young Hoon Lee, Ye-Jin Kim, Min Hyung Lee, Sunghee Park, Jaehoon Jung, and Seunghyup Yoo
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Steric effects ,Dopant ,010405 organic chemistry ,Substituent ,chemistry.chemical_element ,Electroluminescence ,010402 general chemistry ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,OLED ,Iridium ,Physical and Theoretical Chemistry ,Homoleptic ,Phosphorescence - Abstract
Homoleptic tris-cyclometalated iridium complexes, fac-Ir[5-(2-RCB)ppy]3 (3a-3c; CB = o-carboran-1-yl; ppy = 2-phenylpyridinato-C(2),N; R = H (3a), Me (3b), (i)Bu (3c)) with 2-R-substituted o-carboranes at the 5-position of the ppy ligand, were prepared and characterized. X-ray diffraction analysis of 3a and 3c revealed that the three C^N ligands adopt a fac-arrangement around the Ir atom and that the carboranyl C-C bond distance increases with increasing steric effects of the 2-R substituent. The phosphorescence wavelengths of the complexes were apparently blue-shifted by ca. 20 nm (λem = 487-493 nm) compared to that of the parent fac-Ir(ppy)3 (4; λem = 508 nm). In particular, 3a-3c were highly emissive in toluene, and the phosphorescence quantum efficiencies of 3a and 3b (ΦPL = 0.95-0.98) were comparable to that of 4. Solution-processed electroluminescent devices incorporating 3a-3c as emitters displayed green light with high performance, and devices based on the 3c dopant showed the highest performance. In particular, the devices based on 3c exhibited performance more than double of that of the device based on 4 in terms of current efficiency (29.6 cd/A for 3c vs 15.8 cd/A for 4 at 4 wt % Ir and 1000 cd/m(2)), power efficiency (11.0 lm/W for 3c vs 6.3 lm/W for 4), and external quantum efficiency (10.2% for 3c vs 4.7% for 4) over a wide range of luminance. The higher PL quantum yields of doped host films with 3c than those with 4 at high dopant concentrations above 8 wt % suggested that along with high phosphorescence quantum efficiency, the steric bulkiness of the 2-(i)Bu-substituted o-carborane in 3c plays a crucial role in improving device performance.
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- 2016
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34. The substituent effect of 2-R-o-carborane on the photophysical properties of iridium(<scp>iii</scp>) cyclometalates
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Young Hoon Lee, Jihyun Park, Ji Yeon Ryu, Min Hyung Lee, and Junseong Lee
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chemistry.chemical_classification ,010405 organic chemistry ,Aryl ,Substituent ,chemistry.chemical_element ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Inorganic Chemistry ,Bond length ,chemistry.chemical_compound ,chemistry ,Electronic effect ,Carborane ,Iridium ,HOMO/LUMO ,Alkyl - Abstract
A family of heteroleptic iridium(III) cyclometalates, [4-(2-RCB)ppy]2Ir(acac) (3c–3g; CB = o-carboran-1-yl; ppy = 2-phenylpyridinato-C2,N; acac = acetylacetonate; R = iPr (3c), iBu (3d), Ph (3e), CF3C6H4 (3f), C6F5 (3g)) with various 2-R substituted o-carboranes at the 4-position in the phenyl ring of the ppy ligand, were prepared. The X-ray crystal structure of all complexes, including 3a (R = H) and 3b (R = Me), showed that while the carboranyl C–C bond distance increases with the increasing steric effect of the 2-R substituent (3a–3d), the bond distance is more likely to be influenced by the electronic effect of the substituent for the 2-aryl substituted complexes (3e–3g). The absorption and emission bands of all complexes were red-shifted with respect to those of the parent (ppy)2Ir(acac) (4). While 3a–3d exhibited intense green phosphorescence with good quantum efficiency in toluene (ΦPL = 0.17–0.47), the complexes were poorly emissive in THF (ΦPL < 0.004). In a PMMA film, however, 3a–3d became substantially emissive (ΦPL = 0.11–0.14, 8 wt% Ir), albeit less emissive than 4 (ΦPL = 0.15). In contrast, the 2-aryl substituted 3e–3g were almost non-emissive in both the solution and solid states. All complexes underwent facile carborane-centered, electrochemical reduction (Eonset = −2.01 to −1.22 V). The potential values of these reductions increased with increases in the electron accepting ability of the 2-R group (H < alkyl < aryl) and were largely shifted anodically with respect to those of 4 and 5-carborane substituted complexes. This reduction behavior of 3a–3g implies that the LUMO contribution of 2-R-o-carborane units increases through the substitution at the 4-position of the ppy ligand and is influenced by the nature of the 2-R group, which may be responsible for facile carboranyl C–C bond variation leading to efficient quenching of the emissive excited states.
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- 2016
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35. Synthesis of first-generation calix-dendrimer from 1,3,5-tris(aminomethyl)-2,4,6-trimethylbenzene and p-tert-butylcalix[4]arene monomethyl ester
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Besma Mellah, Young Hoon Lee, Jeong Hwan Cho, Dong-Il Kim, and Yang Kim
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Tris ,chemistry.chemical_compound ,Denticity ,chemistry ,Ligand ,Stereochemistry ,Dendrimer ,Calixarene ,General Chemistry ,Condensed Matter Physics ,Medicinal chemistry ,First generation ,Food Science - Abstract
A first-generation calix-dendrimer 1 suitable as a multidentate ligand for metal-ion binding was prepared from 1,3,5-tris(aminomethyl)-2,4,6-trimethylbenzene as the dendrimer core and p-tert-butylcalix [4] arene monomethyl ester as a repetitive branch, and characterized by spectroscopic techniques.
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- 2015
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36. Biochemical and proteomic analysis of soybean sprouts at different germination temperatures
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Sung Cheol Koo, In Youl Baek, Young Hoon Lee, Seong-Bum Baek, Hyun-Tae Kim, Sang Gon Kim, Hyun Young Kim, Hong Tai Yun, Dong-Won Bae, Beom Kyu Kang, and Man Soo Choi
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chemistry.chemical_classification ,ABTS ,DPPH ,Trypsin inhibitor ,Organic Chemistry ,food and beverages ,Fatty acid ,Secondary metabolite ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Hypocotyl ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Germination ,medicine ,Storage protein ,Food science ,medicine.drug - Abstract
Soybean sprouts are available throughout the year and have gained popularity as a functional food owing to their high nutritional value. In the present study, soybean seeds were germinated at different temperatures and the effects on growth characteristics, nutrient composition, and secondary metabolites were investigated. Sprout qualities such as whole length and hypocotyl length were observed to increase at a higher temperature of germination (25 vs. 20 °C). The total protein content of the sprouts increased, whereas the total fatty acid content decreased upon germination at 25 °C. The total phenolic content was higher in soybean sprouts than in soybean seeds. Additionally, antioxidant activity increased in a temperature-dependent manner. Both DPPH and ABTS activity were higher at 25 °C than at 20 °C. Proteomic analysis was conducted to generate temperature responsive protein profiles of soybean sprouts. Using 2D gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, 33 differentially expressed spots were identified. Further analysis of these spots revealed potential function in protein storage and modification. Upon germination at 25 °C, 16 spots increased significantly, whereas 17 protein spots were observed to decrease. Interestingly, a trypsin inhibitor was highly expressed at 25 °C. Semi-quantitative RT-PCR analysis showed that mRNA expression level of most of genes encoding the identified proteins correlated well with their protein abundance, suggesting their temperature-dependent transcriptional regulation in soybean sprouts. In summary, our results clearly indicate an effect of temperature on growth of and secondary metabolite production in soybean sprouts.
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- 2015
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37. Lead(II) Ion Selective Poly(Aniline) Solid Contact Electrode Based on 1,2-bis(N'-Benzoylthioureido)Ethane, -Propane and -Butane Ionophoresk
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Young-Hoon Lee, Tae-Kee Hong, Won-Sik Han, Sung-Min Ahn, and Hak-Joo Lee
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Potassium ,General Chemical Engineering ,Inorganic chemistry ,Ionophore ,chemistry.chemical_element ,Butane ,Analytical Chemistry ,Ion selective electrode ,Polyvinyl chloride ,chemistry.chemical_compound ,Aniline ,chemistry ,Propane ,Moiety - Abstract
The lead ion selective electrodes were manufactured by synthesizing a benzoyl thioureido group ionophores having two sulfur groups on the both ends of ethane, propane and butane molecules. The ionophore containing propane moiety showed the best responsivity to lead ion. With the 1,3-bis(N,N′-benzoylthioureido)propane (BTP) ionophore, the best result was found when it included with the o-nitrophenyloctylether (o-NPOE) plasticizer with the highest permittivity and the oleic acid (OA) additive. The ratio of BTP: polyvinyl chloride: o-NPOE: potassium tetrakis(4-chlorophenyl)borate: OA was 2.5: 16.5: 30.5: 1.5: 0.5, the response range was 1.0 × 10−6.4–1.0 × 10−1.0 M, and the response slope was 30.4 mV/decade. Addition of OA led to an excellent result for the responsivity, cation interference effect, correlation coefficient, response time and reproducibility. The electrode represented constant characteristics irrelevant to variation of pH between 2–7, the stabilization time was 30 s, the response time was about 30 s, and the reproducibility represented ±0.81 and ±1.40 mV for 1.0 × 10−2.0 and 1.0 × 10−3.0 M lead, respectively.
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- 2015
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38. Rigidity-Induced Delayed Fluorescence by Ortho Donor-Appended Triarylboron Compounds: Record-High Efficiency in Pure Blue Fluorescent Organic Light-Emitting Diodes
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Jong Won Shin, Jihun Oh, Jaehoon Jung, Sunghee Park, Min Hyung Lee, Seunghyup Yoo, and Young Hoon Lee
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Materials science ,Carbazole ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,Acceptor ,Fluorescence ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Excited state ,OLED ,General Materials Science ,Quantum efficiency ,Singlet state ,0210 nano-technology ,Phenoxazine - Abstract
A synthetic approach to highly efficient thermally activated delayed fluorescence (TADF) is proposed that uses ortho donor (D)–acceptor (A) compounds (PXZoB, DPAoB, and CzoB), wherein the acceptor is based on triarylboron and the donor is phenoxazine (PXZ), diphenylamine (DPA), or carbazole (Cz). Combined with the ortho D–A connectivity, the bulky nature of the triarylboron endows the D–A dyads with inherent steric “locking” for a highly twisted arrangement, leading to a small energy difference between singlet and triplet excited states (ΔEST) and thus exhibiting very efficient TADF with microsecond-range lifetimes. In sharp contrast, the corresponding para D–A derivatives, DPApB and CzpB, only display short-lived, normal fluorescence. Organic light-emitting diodes (OLEDs) incorporating the proposed ortho D–A compounds as emitters display orange, greenish-blue, and pure blue emission and exhibit high external quantum efficiency (ηEQE). In particular, the pure blue OLEDs based on the proposed ortho D–A emi...
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- 2017
39. Facultative ligands: structural studies of some mono- and binuclear complexes
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Cindy Mora, Jack Harrowfield, Pierre Thuéry, Jong Won Shin, Mihyun Kim, Yang Kim, Young Hoon Lee, Mi Seon Won, Laboratoire de Chimie Moléculaire et de Catalyse pour l'Energie (ex LCCEF) (LCMCE), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Science et d'ingénierie supramoléculaires (ISIS), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
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Facultative ,Denticity ,010405 organic chemistry ,Chemistry ,Ligand ,Stereochemistry ,Imine ,Facultative ligands Functionalised Schiff-bases Mono- and bi-nuclear complexes Crystal structures ,General Chemistry ,Crystal structure ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,3. Good health ,Ion ,chemistry.chemical_compound ,Crystallography ,[CHIM.COOR]Chemical Sciences/Coordination chemistry ,Single crystal ,Stoichiometry ,Food Science - Abstract
International audience; Single crystal, X-ray structure determinations on several transition metal ion complexes of multidentate ligands involving hydroxyl-O, imine-N and heterocycle-N donor atoms have shown that both mononuclear and binuclear species can be formed, depending on the ligand, although the form obtained may depend simply upon the reaction stoichiometry. The structures have been analysed in terms of factors which may influence the complex ion nuclearity.
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- 2014
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40. Manipulation of Phosphorescence Efficiency of Cyclometalated Iridium Complexes by Substitutedo-Carboranes
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Sang Uck Lee, Jihyun Park, Song-Jin Jo, Min Hyung Lee, Miyoung Kim, Junseong Lee, and Young Hoon Lee
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Steric effects ,Aryl ,Organic Chemistry ,Substituent ,chemistry.chemical_element ,General Chemistry ,Photochemistry ,Catalysis ,Bond length ,chemistry.chemical_compound ,chemistry ,Electronic effect ,Iridium ,Phosphorescence ,HOMO/LUMO - Abstract
A series of [(C^N)2 Ir(acac)] complexes [{5-(2-R-CB)ppy}2 Ir(acac)] (3 a-3 g; acac=acetylacetonate, CB=o-carboran-1-yl, ppy=2-phenylpyridine; R=H (3 a), Me (3 b), iPr (3 c), iBu (3 d), Ph (3 e), CF3 C6 H4 (3 f), C6 F5 (3 g)) with various 2-R-substituted o-carboranes at the 5-position in the phenyl ring of the ppy ligand were prepared. X-ray diffraction studies revealed that the carboranyl CC bond length increases with increasing steric and electron-withdrawing effects from the 2-R substituents. Although the absorption and emission wavelengths of the complexes are almost invariant to the change of 2-R group, the phosphorescence quantum efficiency varies from highly emissive (ΦPL ≈0.80 for R=H, alkyl) to poorly emissive (R=aryl) depending on the 2-R group and the polarity of the medium. Theoretical studies suggest that 1) the almost nonemissive nature of the 2-aryl-substituted complexes is mainly attributable to the large contribution to the LUMO in the S1 excited state from an o-carborane unit and 2) the variation in the CC bond length between the S0 and T1 state structures increases with increasing steric (2-alkyl) and electronic effects (2-aryl) of the 2-R substituent and the polarity of the solvent. The solution-processed electroluminescence (EL) devices that incorporated 3 b and 3 d as emitters displayed higher performance than the device based on the parent [(ppy)2 Ir(acac)] complex. Along with the high phosphorescence efficiency, the bulkiness of the 2-R-o-carborane unit is shown to play an important role in improving device performance.
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- 2014
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41. Raphanus sativus L. seeds prevent LPS-stimulated inflammatory response through negative regulation of the p38 MAPK-NF-κB pathway
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Jeong-Chae Lee, Ki Choon Choi, Sung-Ho Kook, Hyoung-Kwon Cho, and Young-Hoon Lee
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Lipopolysaccharides ,Lipopolysaccharide ,MAP Kinase Signaling System ,p38 mitogen-activated protein kinases ,Immunology ,Anti-Inflammatory Agents ,Biology ,Pharmacology ,Nitric Oxide ,Antioxidants ,Cell Line ,Raphanus ,Nitric oxide ,chemistry.chemical_compound ,In vivo ,Sepsis ,Animals ,Immunology and Allergy ,Mice, Inbred ICR ,Plant Extracts ,Macrophages ,NF-kappa B ,NF-κB ,In vitro ,chemistry ,Biochemistry ,Cell culture ,Seeds ,Cytokines ,Female ,Tumor necrosis factor alpha - Abstract
The seeds of Raphanus sativus L. (RSL) have long been used as anti-inflammatory traditional medicine. However, scientific bases for the purported potential of the medicine and the associated mechanisms were barely defined. This study investigated the effects of RSL seeds on lipopolysaccharide (LPS)-stimulated inflammatory responses in vitro and in vivo. Treatment with 100 μg/ml ethyl acetate fraction (REF), which was isolated from water extract of the seeds, significantly inhibited LPS-stimulated production of nitric oxide (P < 0.05), interleukin-6 (P < 0.001), and tumor necrosis factor (TNF)-α (P < 0.001) in RAW264.7 cells. Oral supplementation with 30 mg/kg REF protected mice by 90% against LPS-induced septic death and prevented the increases of serum TNF-α and interferon-γ levels in LPS-injected mice. When REF was divided into four sub-fractions (REF-F1-F4), REF-F3 showed the greatest activity to suppress LPS-stimulated production of inflammatory mediators. We subsequently isolated an active fraction from the REF-F3 and identified sinapic acid as the main constituent. The addition of 50 μg/ml active fraction markedly inhibited LPS-stimulated production of inflammatory mediators by suppressing p38 MAPK and nuclear factor-κB activation. Furthermore, supplementation with the active fraction (10 mg/kg) improved the survival rate of LPS-injected mice by 80% of the untreated control. Additional experiments revealed that sinapic acid was the active component responsible for the anti-inflammatory potential of RSL seeds. Collectively, our current results suggest that both RSL seeds and sinapic acid may be attractive materials for treating inflammatory disorders caused by endotoxins.
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- 2014
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42. The effect of coffee, tea, and caffeine consumption on serum uric acid and the risk of hyperuricemia in Korean Multi-Rural Communities Cohort
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Mi Kyung Kim, Min-Ho Shin, Seong-Kyu Kim, Bo Youl Choi, Young Hoon Lee, Dong Hoon Shin, Pil Sook Park, Byung Yeol Chun, and Jisuk Bae
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Male ,Rural Population ,Immunology ,Hyperuricemia ,Coffee ,chemistry.chemical_compound ,Rheumatology ,Risk Factors ,Caffeine ,Urate metabolism ,Republic of Korea ,Humans ,Immunology and Allergy ,Medicine ,Food science ,Sex Distribution ,Aged ,Tea ,business.industry ,Serum uric acid ,nutritional and metabolic diseases ,Feeding Behavior ,Middle Aged ,medicine.disease ,Uric Acid ,chemistry ,Caffeine consumption ,Multivariate Analysis ,Cohort ,Population data ,Regression Analysis ,Uric acid ,Female ,business - Abstract
Caffeine, a commonly consumed food constituent, is known to exert beneficial physiological effects in humans. There is a lack of comprehensive population data for the effects of caffeine intake on urate metabolism. Therefore, the aim of this study was to determine whether coffee, tea, and caffeine intake influences serum uric acid and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort. We enrolled 9,400 participants in this study. An assessment of various dietary intake amounts of substances such as coffee and tea was performed using a food frequency questionnaire. The content of caffeine was calculated from coffee (74 mg/cup) and tea (15 mg/cup) intake information from the past year. Multivariate logistic regression models, multiple linear regression models, and analysis of covariance were applied to identify any association of dietary intake with serum uric acid levels or the risk of hyperuricemia. No trends for coffee, tea, or caffeine intake were found according to each quintile with serum uric acid in males, although there were weak, marginally significant trends between the content of coffee and caffeine intake and serum uric acid level in females (p = 0.07 for both). Tea intake in males and caffeine intake in females were significantly different between non-hyperuricemia and hyperuricemia (p = 0.04 and p = 0.04, respectively). In addition, a significant association of serum uric acid level with tea intake in males (β = 0.0006, p = 0.02) and with tea intake and caffeine intake in females (β = 0.0003, p = 0.04 and β = 0.0006, p = 0.02, respectively) was observed. There was no effect of coffee, tea, or caffeine intake on the risk of hyperuricemia in either males or females. This study suggests that caffeine consumption might have an effect on serum uric acid in females. However, coffee, tea, and caffeine intake amounts were not associated with the risk of hyperuricemia.
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- 2014
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43. Effect of flow induced alignment on the thermal conductivity of injection molded carbon nanotube-filled polystyrene nanocomposites
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Mehdi Mahmoodi, Simon S. Park, Abdulmajeed A. Mohamad, and Young Hoon Lee
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Nanocomposite ,Materials science ,Polymers and Plastics ,General Chemistry ,Carbon nanotube ,Compression (physics) ,law.invention ,chemistry.chemical_compound ,Thermal conductivity ,chemistry ,law ,Transmission electron microscopy ,Thermal ,Materials Chemistry ,Polystyrene ,Composite material ,Anisotropy - Abstract
Carbon nanotube (CNT) nanocomposites with a polystyrene thermoplastic matrix were injection molded and the high shear stress exerted during the injection process partially enabled the alignment of the CNTs in the flow direction. Nanocomposites with different CNT loadings and degrees of alignment were produced, and their thermal conductivities were measured based on ASTM D5470. The results were compared with compression molded samples featuring random alignments of CNTs. The results showed that the injection molded samples possessed anisotropic thermal conductivities, due to the partial alignment of the CNTs in the flow direction. The effective medium approach was used to analytically estimate the thermal conductivity of the molded samples. Good agreement was observed between the experimental and analytically simulated results in lower CNT concentrations (less than 5 wt% of CNT). Using transmission electron microscopy pictures taken of the nanocomposites, the alignment of CNTs in the thermoplastic matrix were modeled; and their thermal conductivities were simulated using the finite element method. Good agreement was observed between the experiments and simulated results. POLYM. ENG. SCI., 55:753–762, 2015. © 2014 Society of Plastics Engineers
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- 2014
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44. Methylenetetrahydrofolate Reductase 677 Genotype-Specific Reference Values for Plasma Homocysteine and Serum Folate Concentrations in Korean Population Aged 45 to 74 Years: The Namwon Study
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Hae-Sung Nam, Seul-Ki Jeong, Min-Ho Shin, Jin Su Choi, Kyeong Soo Park, Hee Nam Kim, Bok Hee Kim, Seong-Woo Choi, Young Hoon Lee, and Sun-Seog Kweon
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Male ,Percentile ,medicine.medical_specialty ,Aging ,Homocysteine ,Genotype ,Brief Communication ,Cohort Studies ,chemistry.chemical_compound ,Serum folate ,Folic Acid ,Sex Factors ,Reference Values ,Internal medicine ,Republic of Korea ,Medicine ,Humans ,Reference Intervals ,Aged Population ,Methylenetetrahydrofolate Reductase (NADPH2) ,Aged ,biology ,business.industry ,Age Factors ,General Medicine ,Middle Aged ,Occupation & Environmental Medicine ,Endocrinology ,chemistry ,Reference values ,Methylenetetrahydrofolate reductase ,Plasma homocysteine ,biology.protein ,Female ,business ,Cohort study - Abstract
The reference interval for plasma total homocysteine (tHcy) and serum folate concentrations were estimated. Total of 3,154 reference individuals (1,029 men and 2,125 women) were selected based on stringent exclusion criteria. For plasma tHcy concentration (µM/L), reference values (median [5-95 percentile]) were 7.72 (5.03 to 13.80) and 6.09 (3.95-10.19) in men and women, respectively. For serum folate concentration (nM/L), reference values were 23.71 (11.73-38.44) and 28.95 (15.23-40.44) in men and women, respectively. The tHcy levels of both genders in the present study were lower than those in previous reports from other countries and Korea. Graphical Abstract
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- 2014
45. Screening of Soybean Germplasm with High Starch Content
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Sung Cheol Koo, Myeong Gi Jeon, Young Hoon Lee, Hyun-Young Kim, Beom Kyu Kang, Jong Min Go, In Youl Baek, Hong Tai Yun, and Man Soo Choi
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Protein content ,Germplasm ,chemistry.chemical_compound ,chemistry ,Agronomy ,Starch ,Cultivar ,Biology ,Chemical composition - Published
- 2014
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46. Cyanide ion selective solid contact electrode based on nickel complex of N,N′-bis-(4-phenylazosalicylidene)-o-phenylene diamine ionophore
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Hak-Joo Lee, Won-Sik Han, Tae-Kee Hong, Young-Hoon Lee, and Jung-Sub Lee
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chemistry.chemical_compound ,Nickel ,Aqueous solution ,chemistry ,Phenylene ,Diamine ,Cyanide ,Electrode ,Inorganic chemistry ,Ionophore ,chemistry.chemical_element ,Ether ,Analytical Chemistry - Abstract
A cyanide ion selective poly(aniline) solid contact electrode based on nickel complex of N,N′-bis-(4-phenylazosalicylidene)-o-phenylenediamine ionophore was successfully developed. The electrode exhibits a good linear response of 58.7 mV/decade (at 20 ± 0.2°C, r 2 = 0.998) with in the concentration range of 1 × 10−1.0-1 × 10−6.0 M cyanide. The composition of this electrode was: ionophore 0.300, polyvinylchloride 0.300, 2-nitrophenyloctyl ether 0.670 (mass). This 2-nitrophenyloctyl ether plasticizer provides the best response characteristics. The electrode shows good selectivity for cyanide ion in comparison with any other anions and is suitable for use with aqueous solutions of pH 4.6–6.3. The standard deviations of the measured emf difference were ±1.92 and ±1.87 mV for cyanide sample solutions of 1.0 × 10−2 M and 1.0 × 10−3 M, respectively. The stabilization time was less than 183 s and response time was less than 38 s.
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- 2014
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47. Terpyridine–Triarylborane Conjugates for the Dual Complexation of Zinc(II) Cation and Fluoride Anion
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Sang Uck Lee, Junseong Lee, Young Hoon Lee, Nguyen Van Nghia, Min Jeong Go, and Min Hyung Lee
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Organic Chemistry ,Inorganic chemistry ,chemistry.chemical_element ,Zinc ,Crystal structure ,Ring (chemistry) ,Adduct ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,chemistry ,Physical and Theoretical Chemistry ,Terpyridine ,Absorption (chemistry) ,Fluoride ,Conjugate - Abstract
A series of ditopic terpyridine–triarylborane conjugates (1–3) in which 4′-ethynylterpyridine is linked to the para, meta, and ortho positions of the phenyl ring of dimesitylphenylborane (Mes2PhB), respectively, were prepared to investigate the dual complexation behavior of the conjugates toward Zn(II) cation and fluoride anion. The crystal structures of the corresponding Zn(II) complexes (L·ZnCl2, L = 1–3) reveal the formation of a 1:1 adduct between ZnCl2 and a conjugate, with a five-coordinate Zn(II) center bound to three nitrogen atoms and two chlorine atoms. In particular, the structure of ortho-substituted 3·ZnCl2 in comparison with that of 3 indicates the presence of π–π interactions between the mesityl ring and ethynylene–pyridine fragment in 3·ZnCl2. UV/vis absorption and fluorescence spectra of 1–3 display low-energy bands mainly assignable to a π(Ar) → pπ(B) (Ar = Mes and/or phenylene–ethynylene) charge transfer (CT) transition. The transition in Zn(II) complexes has a π(Mes) → π*(Ar) (Ar = ter...
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- 2014
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48. Coumestrol induces senescence through protein kinase CKII inhibition-mediated reactive oxygen species production in human breast cancer and colon cancer cells
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Young-Seuk Bae, Young-Hoon Lee, Heung Joo Yuk, and Ki-Hun Park
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Male ,Senescence ,endocrine system ,Coumestrol ,Down-Regulation ,Breast Neoplasms ,Analytical Chemistry ,chemistry.chemical_compound ,Cell Line, Tumor ,Humans ,Casein Kinase II ,Cellular Senescence ,Cell Proliferation ,chemistry.chemical_classification ,Reactive oxygen species ,NADPH oxidase ,biology ,Plant Extracts ,General Medicine ,HCT116 Cells ,Molecular biology ,Kinetics ,chemistry ,Biochemistry ,Colonic Neoplasms ,Apocynin ,Cancer cell ,biology.protein ,Female ,Soybeans ,P22phox ,Growth inhibition ,Reactive Oxygen Species ,Food Science - Abstract
An inhibitor of the protein kinase CKII (CKII) was purified from leaves of Glycine max (L.) Merrill and was identified as coumestrol by structural analysis. Coumestrol inhibited the phosphotransferase activity of CKII toward β-casein, with an IC50 of about 5 μM. It acted as a competitive inhibitor with respect to ATP as a substrate, with an apparent Ki value of 7.67 μM. Coumestrol at 50 μM resulted in 50% and 30% growth inhibition of human breast cancer MCF-7 and colorectal cancer HCT116 cells, respectively. Coumestrol promoted senescence through the p53-p21Cip1/WAF1 pathway by inducing reactive oxygen species (ROS) production in MCF-7 and HCT116 cells. The ROS scavenger N-acetyl- l -cysteine (NAC), NADPH oxidase inhibitor apocynin and p22phox siRNA almost completely abolished this event. Overexpression of CKIIα antagonised cellular senescence mediated by coumestrol, indicating that this compound induced senescence via a CKII-dependent pathway. Since senescence is an important tumour suppression process in vivo, these results suggest that coumestrol can function by inhibiting oncogenic disease, at least in part, through CKII inhibition-mediated cellular senescence.
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- 2013
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49. The impact of serum uric acid level on arterial stiffness and carotid atherosclerosis: The Korean Multi-Rural Communities Cohort study
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Bo Youl Choi, Byung-Yeol Chun, Mi Kyung Kim, Min-Ho Shin, Seong-Kyu Kim, Ji Suk Bae, Young-Hoon Lee, Dong Hoon Shin, and Pil Sook Park
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Adult ,Carotid Artery Diseases ,Male ,Rural Population ,medicine.medical_specialty ,Population ,Hyperuricemia ,Pulse Wave Analysis ,Carotid Intima-Media Thickness ,Gastroenterology ,Cohort Studies ,chemistry.chemical_compound ,Vascular Stiffness ,Asian People ,Internal medicine ,Republic of Korea ,medicine ,Humans ,Ankle Brachial Index ,Risk factor ,education ,Pulse wave velocity ,Aged ,education.field_of_study ,business.industry ,Middle Aged ,medicine.disease ,Uric Acid ,Carotid Arteries ,Endocrinology ,chemistry ,Intima-media thickness ,Cohort ,Arterial stiffness ,Uric acid ,Female ,Cardiology and Cardiovascular Medicine ,business - Abstract
Serum uric acid level has been found to be associated with a risk factor for cardiovascular diseases. However, the topic has not been explored in the general population, especially in Korea. This study was designed to determine whether serum uric acid is associated with carotid atherosclerosis and arterial stiffness in the Korean Multi-Rural Communities Cohort study.A total of 5568 participants from the Korean Multi-Rural Communities Cohort were evaluated for the risk of hyperuricemia in cardiovascular atherosclerosis. Important surrogates for cardiovascular atherosclerosis such as intima-media thickness (IMT) and brachial-ankle pulse wave velocity (baPWV) were assessed. We evaluated the association between these atherosclerosis indices and serum uric acid level or hyperuricemia through multivariate-adjusted logistic and linear regression analyses.There was a significant difference of carotid IMT and baPWV between males and females (p0.0001, respectively). Both male and female subjects with hyperuricemia showed higher baPWV than subjects without hyperuricemia (p = 0.0004 for males; p = 0.001 for females). Serum uric acid level was positively correlated with baPWV in males (β = 0.0006, p0.0001) and in females (β = 0.0001, p = 0.04), whereas no association between serum uric acid and carotid IMT was found in either gender. A linear relationship of baPWV with increasing serum uric acid level was observed in males (p = 0.0005) and in females (p = 0.004).Serum uric acid level could be considered an important risk factor for arterial stiffness in Korean population, whereas carotid IMT is not associated with serum uric acid in either gender when using data from the Korean Multi-Rural Communities Cohort study.
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- 2013
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50. Quaterphenylterpyridine: Synthesis and Metal‐Ion Complexation
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Alexandre N. Sobolev, Young Hoon Lee, Akira Fuyuhiro, Shinya Hayami, Yang Kim, and Jack Harrowfield
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Ligand ,chemistry.chemical_element ,Crystal structure ,Zinc ,Photochemistry ,Fluorescence spectroscopy ,Inorganic Chemistry ,Metal ,chemistry.chemical_compound ,Crystallography ,chemistry ,visual_art ,X-ray crystallography ,visual_art.visual_art_medium ,Dimethylformamide - Abstract
A quaterphenylterpyridine ligand (qptpy) with the rodlike quaterphenyl unit attached in the 4-position has been synthesised by a Pd-catalysed Suzuki cross-coupling reaction. A crystal structure determination on the complex [Zn(qptpy)Cl2]·dmf (dmf = dimethylformamide) has shown the ligand to be bound in the expected N3-tridentate manner to the essentially trigonal-bipyramidal dichloro metal ion, with the quaterphenyl substituents involving a twisted array of the separate phenyl groups and the shortest contacts between aro
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- 2013
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