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Amaresh S, Karthikeyan K, Kim KJ, Lee YG, Lee YS. Aluminum based sulfide solid lithium ionic conductors for all solid state batteries. NANOSCALE 2014; 6:6661-6667. [PMID: 24816684 DOI: 10.1039/c4nr00804a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The present work focuses on the synthesis of lithium ionic conductors based on a Li2S-Al2S3-GeS-P2S5 system due to the high ionic conductivity exhibited by the constituents of this system. Mechanical milling for a short duration and a single step heat treatment at a moderate temperature of 550 °C resulted in crystalline powders with high lithium ionic conductivity at room temperature that are comparable to the organic liquid electrolytes. The effect of various aluminum to germanium ratios was studied. Among the samples containing Al : Ge, the ratio of 30 : 70 was found to show high ionic conductivities of 1.7 × 10(-3) S cm(-1) at 25 °C and ∼ 6 × 10(-3) S cm(-1) at 100 °C equivalent. The activation energy of this material was significantly less (Ea = 17 kJ mol(-1)), which can be considered to be the best value among solid electrolytes. The electrochemical stability was analyzed using cyclic voltammetry between -0.3 and 5.0 V and it was found that the voltammetric profile was smooth without any additional current response, due to electrolyte decomposition, or any other side reaction, except a pair of lithium deposition and stripping peaks.
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Ooi SQ, Chan RME, Poh LKS, Loke KY, Heng CK, Chan YH, Gan SU, Lee KO, Lee YS. Visfatin and its genetic variants are associated with obesity-related morbidities and cardiometabolic risk in severely obese children. Pediatr Obes 2014; 9:81-91. [PMID: 23447513 DOI: 10.1111/j.2047-6310.2013.00149.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Revised: 12/28/2012] [Accepted: 01/10/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND Visfatin is an adipokine, associated with obesity and possibly glucose regulation. OBJECTIVE The aim of this study was to examine the association of visfatin and its genetic variants with adiposity, cardiometabolic risk factors and obesity-related morbidities in obese children. METHODS Anthropometric measurements, dual energy X-ray absorptiometry scan, fasting blood samples and oral glucose tolerance tests were performed for 243 obese children. We screened the visfatin gene of 24 obese subjects and then performed genotyping of identified genetic variants in other 219 obese children through direct DNA sequencing. RESULTS Fasting serum visfatin correlated with measures of obesity and liver enzymes and was elevated in obese children with abnormal glucose tolerance and non-alcoholic fatty liver disease. The two upstream single nucleotide polymorphisms, -3187G>A (rs11977021) and -1537C>T (rs61330082), were at complete linkage disequilibrium. The AA genotype of -3187G>A was associated with higher serum visfatin (6.17 ± 0.76 ng mL(-1) vs. 3.92 ± 0.44 ng mL(-1)) and higher triglyceride (1.39 ± 0.08 mmol L(-1) vs. 1.19 ± 0.07 mmol L(-1)) as compared with the GG genotype. There was also a significant linear increase in serum visfatin across GG to GA to AA genotype of -3187G>A, indicating possible additive effect of A allele. The dominant GA + AA genotype model of +21426G>A (rs2302559) was associated with lower serum visfatin (3.83 ± 0.56 ng mL(-1) vs. 5.13 ± 0.34 ng mL(-1)) and lower plasma glucose (4.37 ± 0.08 mmol L(-1) vs. 4.77 ± 0.12 mmol L(-1)) as compared with the GG genotype. CONCLUSION Visfatin and its genetic variants were associated with adiposity, obesity-related morbidities and adverse cardiometabolic parameters. This supported our hypothesis that visfatin plays a significant role in the development of obesity-related morbidities and cardiometabolic risk.
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Kim D, Kim JH, Lee M, Lee YS, Kang S. Experimental investigation into effect of annealing treatment on springback of magnesium alloy sheets. ACTA ACUST UNITED AC 2013. [DOI: 10.1179/143307511x12858956848191] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Yang PLS, Lu Y, Khoo CM, Leow MKS, Khoo EYH, Teo A, Lee YS, Das De S, Chong YS, Gluckman PD, Tai ES, Venkataraman K, Ng CMA. Associations between ethnicity, body composition, and bone mineral density in a Southeast Asian population. J Clin Endocrinol Metab 2013; 98:4516-23. [PMID: 24037892 DOI: 10.1210/jc.2013-2454] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT AND OBJECTIVE Chinese men in Singapore have a higher incidence of hip fractures than Malay and Indian men. We investigated whether there were corresponding ethnic differences in peak bone mineral density (BMD) in young men and whether differences in body composition influenced peak BMD. DESIGN AND SETTING This was a cross-sectional study of healthy volunteers in a tertiary medical center. PARTICIPANTS A total of 100 Chinese, 82 Malay, and 80 Indian men aged 21 to 40 years, with body mass index between 18 and 30 kg/m(2) underwent dual-energy x-ray absorptiometry to assess BMD, lean mass (LM) and fat mass (FM), and magnetic resonance imaging to quantify abdominal subcutaneous and visceral adipose tissue. Multiple linear regression models, with adjustment for age and height (as a proxy for skeletal size), were used. RESULTS Malay and Indian men had significantly higher BMD than Chinese men at the lumbar spine (Malay: B, 0.06 ± 0.02, P = .001; Indian: B, 0.03 ± 0.02, P = .049), femoral neck (Malay: B 0.04 ± 0.02, P = .034; Indian: B, 0.04 ± 0.02, P = .041), hip (Malay: B, 0.05 ± 0.02, P = .016; Indian: B, 0.06 ± 0.02, P = .001), and ultradistal radius (Malay: B, 0.03 ± 0.01, P < .001; Indian: B, 0.02 ± 0.01, P = .029), and this difference was retained after adjustment for LM and FM, except in Malay men at the femoral neck and in Indian men at the ultradistal radius. LM was an important independent determinant of BMD at all sites, whereas FM, subcutaneous adipose tissue, and visceral adipose tissue were not significantly associated with BMD at any site. CONCLUSIONS Lower peak BMD in Chinese men may partly explain the higher fracture incidence in this ethnic group. Further studies are needed to elucidate the reasons for these ethnic differences in bone accumulation.
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Kim BJ, Lee YS, Lee SY, Park SY, Dieplinger H, Yea K, Lee SH, Koh JM, Kim GS. Afamin stimulates osteoclastogenesis and bone resorption via Gi-coupled receptor and Ca2+/calmodulin-dependent protein kinase (CaMK) pathways. J Endocrinol Invest 2013; 36:876-82. [PMID: 23698732 DOI: 10.3275/8975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Afamin was recently identified as a novel osteoclast-derived coupling factor that can stimulate the in vitro and in vivo migration of preosteoblasts. AIM In order to understand in more detail the biological roles of afamin in bone metabolism, we investigated its effects on osteoclastic differentiation and bone resorption. METHODS Osteoclasts were differentiated from mouse bone marrow cells. Tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells were considered as osteoclasts, and the resorption area was determined by incubating the cells on dentine discs. The intracellular cAMP level was determined using a direct enzyme immunoassay. Signaling pathways were investigated using western blot and RT-PCR. Recombinant afamin was administered exogenously to bone cell cultures. RESULTS Afamin stimulated both osteoclastogenesis and in vitro bone resorption. Consistently, the expressions of osteoclast differentiation markers were significantly increased by afamin. Although afamin mainly affected the late-differentiation stages of osteoclastogenesis, the expression levels of receptor activator of nuclear factor-κB ligand (RANKL)-dependent signals were not changed. Afamin markedly decreased the levels of intracellular cAMP with reversal by pretreatment with pertussis toxin (PTX), a specific inhibitor of Gi-coupled receptor signaling. In addition, PTX almost completely blocked afamin-stimulated osteoclastogenesis. Furthermore, pretreatment with KN93 and STO609 - Ca2+/cal - mo dulin-dependent protein kinase (CaMK) and CaMK kinase inhibitors, respectively - significantly prevented decreases in the intracellular cAMP level by afamin while attenuating afamin-stimulated osteoclastogenesis. CONCLUSION Afamin enhances osteoclastogenesis by decreasing intracellular cAMP levels via Gi-coupled receptor and CaMK pathways.
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Kang JH, Kim YK, Park JY, Noh ES, Jeong JE, Lee YS, Choi TJ. Development of microsatellite markers for a hard-shelled mussel, Mytilus coruscus, and cross-species transfer. GENETICS AND MOLECULAR RESEARCH 2013; 12:4009-17. [PMID: 24089090 DOI: 10.4238/2013.september.27.2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The Korean mussel Mytilus coruscus, an endemic marine bivalve mollusk, is economically important. Its population is currently decreasing due to overexploitation and invasion of a more competitive species, Mytilus galloprovincialis. In this study, microsatellite markers for M. coruscus were developed using a cost-effective pyrosequencing technique. Among the 33,859 dinucleotide microsatellite sequences identified, 176 loci that contained more than 8 CA, CT, or AT repeats were selected for primer synthesis. Sixty-four (36.4%) primer sets were produced from the 100- to 200-bp polymerase chain reaction products obtained from 2 M. coruscus individuals. Twenty of these were chosen to amplify DNA from 82 M. coruscus individuals, and 18 polymorphic loci and 2 monomorphic loci were selected as microsatellite markers. The number of alleles and the allele richness of the polymorphic loci ranged from 2 to 22 and from 2.0 to 19.7 with means of 10.8 and 10.1, respectively. Null alleles were detected for all but three loci, which resulted in an observed heterozygosity lower than the expected heterozygosity and therefore an excess of homozygotes. In a cross-species transfer analysis of these markers using 7 Mytilidae species, the locus Mc65 was amplified from all species tested and was found to be polymorphic in all of them. Among the species, M. galloprovincialis, Lithophaga curta, and Hormomya mutabilis showed the same transferability of 25%, but the five amplified loci were polymorphic only in M. galloprovincialis and H. mutabilis. These microsatellite markers may be useful for future resource management and artificial production of juveniles for aquaculture.
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Pilon DV, Lui CH, Han TH, Shrekenhamer D, Frenzel AJ, Padilla WJ, Lee YS, Gedik N. Spin-induced optical conductivity in the spin-liquid candidate herbertsmithite. PHYSICAL REVIEW LETTERS 2013; 111:127401. [PMID: 24093299 DOI: 10.1103/physrevlett.111.127401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Indexed: 06/02/2023]
Abstract
We report a direct measurement of the low-frequency optical conductivity of large-area single-crystal herbertsmithite, a promising spin-liquid candidate material, by means of terahertz time-domain spectroscopy. In the spectral range below 1.4 THz, we observe a contribution to the real part of the in-plane conductivity σ(ab)(ω) from the spin degree of freedom. This spin-induced conductivity exhibits a power-law dependence on frequency σ(ab)(ω) ~ ω(β) with β ≈ 1.4. Our observation is consistent with the theoretically predicted low-frequency conductivity arising from an emergent gauge field of a gapless U(1) Dirac spin liquid.
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Karthikeyan K, Amaresh S, Kim KJ, Kim SH, Chung KY, Cho BW, Lee YS. A high performance hybrid capacitor with Li2CoPO4F cathode and activated carbon anode. NANOSCALE 2013; 5:5958-5964. [PMID: 23708774 DOI: 10.1039/c3nr00760j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
For the first time, we report the possibility of utilizing Li2CoPO4F as a novel cathode material for hybrid capacitor applications. Li2CoPO4F powders were prepared by a conventional two-step solid state method. A hybrid cell was fabricated using Li2CoPO4F as the cathode along with activated carbon (AC) as the anode in 1 M LiPF6 dissolved in 1 : 1 EC/DMC electrolyte and its electrochemical properties were examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and constant current charge-discharge (C-D) techniques. The Li2CoPO4F/AC cell is capable of delivering a discharge capacitance of 42 F g(-1) at 150 mA g(-1) current density within 0-3 V region having excellent coulombic efficiency of over 99% even after 1000 cycles. Furthermore, the Li2CoPO4F/AC cell exhibited excellent rate performance with an energy density of ~24 W h kg(-1) at 1100 mA g(-1) current and maintained about 92% of its initial value even after 30,000 C-D cycles. Electrochemical impedance spectroscopy was conducted to corroborate the results that were obtained and described.
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Kim H, Lee SK, Hong MW, Park SR, Lee YS, Kim JW, Lee HK, Jeong DK, Song YH, Lee SJ. Association of a single nucleotide polymorphism in the akirin 2 gene with economically important traits in Korean native cattle. Anim Genet 2013; 44:750-3. [PMID: 23718263 DOI: 10.1111/age.12055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2013] [Indexed: 11/29/2022]
Abstract
The akirin 2 gene, located on chromosome 9 in cattle, was previously reported to be associated with nuclear factor-kappa B (NF-κB), involved in immune reactions and marbling of meat. To determine whether a single nucleotide polymorphism (SNP) in akirin 2 is associated with economically important traits of Korean native cattle, the c.*188G>A SNP DNA marker in the 3'-UTR region of akirin 2 was analyzed for its association with carcass weight, longissimus muscle area and marbling. The c.*188G>A SNP was genotyped by polymerase chain reaction restriction fragment length polymorphism, and the frequency of the AA, AG, and GG genotypes were 6.82%, 71.29% and 21.88% respectively. This SNP was significantly associated with longissimus muscle area (Bonferroni corrected P < 0.05), and marbling score (Bonferroni corrected P < 0.01). These results suggest that the c.*188G>A SNP of akirin 2 might be useful as a DNA marker for longissimus muscle area and marbling scores in Korean native cattle.
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Lee JY, Shin TJ, Choi JM, Seo KS, Kim HJ, Yoon TG, Lee YS, Han H, Chung HJ, Oh Y, Jung SJ, Shin KJ. Antinociceptive curcuminoid, KMS4034, effects on inflammatory and neuropathic pain likely via modulating TRPV1 in mice. Br J Anaesth 2013; 111:667-72. [PMID: 23719767 DOI: 10.1093/bja/aet176] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Curcumin, the active ingredient of turmeric (Curcuma longa), has a wide range of beneficial effects including anti-inflammation and analgesia. However, poor bioavailability of curcumin hinders its clinical application. To overcome this limitation, we modified the structure of curcumin and synthesized new derivatives with favourable pharmacokinetic profiles. Recently, curcumin has been shown to have an antagonizing effect on transient receptor potential vanilloid type 1 (TRPV1) ion channels. We investigated the antinociceptive activity of KMS4034 which had the most favourable pharmacokinetics among the tested curcumin derivatives. METHODS To evaluate the mechanism of the antinociceptive effects of KMS4034, capsaicin (I(CAP))- and heat (I(heat))-induced currents in TRPV1 expressing HEK293 cells were observed after the application of KMS4034. Nociceptive behavioural measurement using the hot-plate test, formalin test, and chronic constriction injury (CCI) model were evaluated in mice. Also, calcitonin gene-related peptide (CGRP) was stained immunohistochemically in the L4/5 dorsal horns in mice with neuropathic pain. RESULTS I(CAP) (P<0.01) and I(heat) (P<0.05) of TRPV1 were significantly blocked by 10 μM KMS4034. Behaviourally, noticeable antinociceptive effects after 10 mg kg(-1) of KMS4034 treatment were observed in the first (P<0.05) and second phases (P<0.05) of the formalin and hot-plate tests. The mechanical threshold of CCI mice treated with 10 mg kg(-1) KMS4034 was significantly increased compared with control. Immunohistochemical CGRP expression was decreased in the lamina I-II of the lumbar dorsal horns in KMS4034-treated CCI mice compared with the control (P<0.05). CONCLUSIONS KMS4034 may be an effective analgesic for various pain conditions.
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Cukier H, Peralta R, Jin H, Cheng Y, Nedunuri V, Salehi S, Lee YS, Young A. Abstract 4649: Utilization of KLF-4 as a pharmacodynamic biomarker for in vivo anticancer activity of a novel small molecule drug LOR-253. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-4649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
LOR-253 is a potent and selective growth inhibitor of several cancer types, including non-small cell lung cancer (NSCLC), colon cancer and leukemia. LOR-253 stimulates Krüppel Like Factor-4 (KLF-4), a tumor suppressor factor which is characteristically deficient in a variety of cancers, and so represents a new approach to cancer therapy. The current Phase I dose-escalation study is being conducted at Memorial Sloan-Kettering Cancer Center in New York and MD Anderson Cancer Center in Houston. In the present preclinical study, the changes in KLF-4 expression levels were evaluated in vivo to examine the utility of KLF-4 as a pharmacodynamic biomarker, aiming at linking the antitumor effects of LOR-253 to the induction of KLF-4. In the human H226 NSCLC xenograft mouse model, LOR-253 demonstrated dose-dependent antitumor activity when administered at 1, 5, and 15 mg/kg and mediated significant tumor growth inhibition of about 55% at the highest dose given by intravenous bolus injection (p=0.05). Tumors were harvested 24h after the last dose following the treatments at 1, 5, and 15 mg/kg and KLF-4 mRNA and protein levels were analyzed by real-time RT-PCR and Western blot, respectively. A dose-dependent induction of KLF-4 mRNA and protein levels was observed. Pharmacodynamic studies to characterize the effect of LOR-253 on intratumoral KLF-4 were also conducted in the H226 NSCLC xenograft mouse model to determine the optimal time point for tumor biopsy sampling, following the treatment schedule in the ongoing Phase 1 clinical trial (2 days dosing, 12 day break, 2 days of dosing, 12 day break (1 cycle)). Tumor samples were taken 24h after the second, fourth and eighth dose of LOR-253 and analyzed for KLF-4 expression. It was determined that tumor sampling after the second and eighth doses was optimal at demonstrating increased intratumoral KLF-4 levels. Furthermore, antitumor efficacy of LOR-253 was also evaluated in nude rats bearing established human H226 NSCLC tumors when LOR-253 was infused intravenously following the current Phase I clinical dosing schedule. A significant efficacy was observed at the end of the first cycle of treatment, demonstrating 44% decrease in mean tumor volume when compared with the control treatment (p=0.025). Inhibition of tumor growth was paralleled by the induction of KLF-4 in isolated tumors when analyzed by real-time RT-PCR and Western blot. Taken together, the in vivo data obtained in both mouse and rat models provide strong preclinical support for utilizing KLF-4 as a potential pharmacodynamic biomarker for LOR-253 treatment in clinic.
Citation Format: Howard Cukier, Robert Peralta, Hongnan Jin, Yu Cheng, Venkata Nedunuri, Salah Salehi, Yoon S. Lee, Aiping Young. Utilization of KLF-4 as a pharmacodynamic biomarker for in vivo anticancer activity of a novel small molecule drug LOR-253. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4649. doi:10.1158/1538-7445.AM2013-4649
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Lee YS, Lee SJ, Seo KW, Bae JU, Park SY, Kim CD. Homocysteine induces COX-2 expression in macrophages through ROS generated by NMDA receptor-calcium signaling pathways. Free Radic Res 2013; 47:422-31. [PMID: 23485152 DOI: 10.3109/10715762.2013.784965] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Homocysteine (Hcy) at elevated levels is a putative risk factor for many cardiovascular disorders including atherosclerosis. In the present study, we investigated the effect of Hcy on the expression of cyclooxygenase (COX)-2 in murine macrophages and the mechanisms involved. Hcy increased the expression of COX-2 mRNA and protein in dose- and time-dependent manners, but did not affect COX-1 expression. Hcy-induced COX-2 expression was attenuated not only by the calcium chelators, EGTA and BAPTA-AM, but also by an antioxidant, N-acetylcysteine. Calcium chelators also attenuated Hcy-induced reactive oxygen species (ROS) production in macrophages, indicating that Hcy-induced COX-2 expression might be mediated through ROS generated by calcium-dependent signaling pathways. In another series of experiments, Hcy increased the intracellular concentration of calcium in a dose-dependent manner, which was attenuated by MK-801, an N-methyl-D-aspartate (NMDA) receptor inhibitor, but not by bicuculline, a gamma-aminobutyric acid receptor inhibitor. Molecular inhibition of NMDA receptor using small interfering RNA also attenuated Hcy-induced increases in intracellular calcium. Furthermore, both ROS production and Hcy-induced COX-2 expression were also inhibited by MK-801 as well as by molecular inhibition of NMDA receptor. Taken together, these findings suggest that Hcy enhances COX-2 expression in murine macrophages by ROS generated via NMDA receptor-mediated calcium signaling pathways.
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Aris IM, Soh SE, Tint MT, Liang S, Chinnadurai A, Saw SM, Kwek K, Godfrey KM, Gluckman PD, Chong YS, Yap FKP, Lee YS. Body fat in Singaporean infants: development of body fat prediction equations in Asian newborns. Eur J Clin Nutr 2013; 67:922-7. [PMID: 23549200 DOI: 10.1038/ejcn.2013.69] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 02/21/2013] [Accepted: 02/22/2013] [Indexed: 11/09/2022]
Abstract
BACKGROUND/OBJECTIVES Prediction equations are commonly used to estimate body fat from anthropometric measurements, but are population specific. We aimed to establish and validate a body composition prediction formula for Asian newborns, and compared the performance of this formula with that of a published equation. SUBJECTS/METHODS Among 262 neonates (174 from day 0, 88 from days 1-3 post delivery) from a prospective cohort study, body composition was measured using air-displacement plethysmography (PEA POD), with standard anthropometric measurements, including triceps and subscapular skinfolds. Using fat mass measurement by PEA POD as a reference, stepwise linear regression was utilized to develop a prediction equation in a randomly selected subgroup of 62 infants measured on days 1-3, which was then validated in another subgroup of 200 infants measured on days 0-3. RESULTS Regression analyses revealed subscapular skinfolds, weight, gender and gestational age were significant predictors of neonatal fat mass, explaining 81.1% of the variance, but not triceps skinfold or ethnicity. By Bland-Altman analyses, our prediction equation revealed a non-significant bias with limits of agreement (LOA) similar to those of a published equation for infants measured on days 1-3 (95% LOA: (-0.25, 0.26) kg vs (-0.23, 0.21) kg) and on day 0 (95% LOA: (-0.19, 0.17) kg vs (-0.17, 0.18) kg). The published equation, however, exhibited a systematic bias in our sample. CONCLUSIONS Our equation requires only one skinfold site measurement, which can significantly reduce time and effort. It does not require the input of ethnicity and, thus, aid its application to other Asian neonatal populations.
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Kim M, Jin YB, Lee K, Lee YS. A new antiallergic agent that binds to dimerized translationally controlled tumor protein and inhibits allergic symptoms is nontoxic. Hum Exp Toxicol 2013; 32:1119-25. [PMID: 23536520 DOI: 10.1177/0960327113477873] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Dimerized translationally controlled tumor protein (dTCTP) plays a role in allergic diseases. A 7-mer peptide, dimerized translationally binding protein 2 (dTBP2), binds to dTCTP and inhibits dTCTP, suggesting that the 7-mer peptide may have therapeutic potential. We assessed the safety of dTBP2 by examining its cytotoxicity to both human bronchial epithelial cells and mice. dTBP2 did not cause cytotoxicity to the epithelial cells in concentrations up to 100 μg/ml. Also, dTBP2 caused no adverse effects upon repeated administration of 50 mg/kg over 24 h to mice. Hence, we conclude that dTBP2 is a safe candidate drug for use in the therapy of allergic diseases.
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Hong DG, Park NY, Chong GO, Cho YL, Park IS, Lee YS, Lee DH. Laparoscopic transperitoneal infrarenal para-aortic lymphadenectomy in patients with FIGO stage IB1-II B cervical carcinoma. JSLS 2013; 16:229-35. [PMID: 23477170 PMCID: PMC3481238 DOI: 10.4293/108680812x13427982376266] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
These authors suggest that laparoscopic transperitoneal infrarenal lymphadenectomy for cervical cancer is a feasible, safe procedure. Background and Objectives: This study aimed to evaluate the safety, feasibility, and clinical outcomes of laparoscopic transperitoneal infrarenal para-aortic lymphadenectomy in patients with FIGO stage IB1-IIB cervical carcinoma. Methods: Between August 1999 and April 2009, we performed 59 laparoscopic transperitoneal lymphadenectomies; specifically, 12 procedures were performed up to the level of the left renal vessels, and 47 procedures were performed up to the level of the inferior mesenteric artery. We retrospectively analyzed the pathology reports and clinical data and compared the 2 groups. The data were analyzed with a nonparametric Mann-Whitney test, Kaplan-Meier log-rank test, and Pearson's correlation analysis. Results: The 2 groups did not significantly differ with respect to histologic type (P=.093), clinical stage (P=.053), tumor size (P=.383), time interval to start adjuvant therapy postoperatively (P=.064), and type of adjuvant therapy (P=.407). The blood loss (P=.131), operative time (P=.200), mean hospital stay (P=.417), and postoperative self-voiding (P=.306) did not significantly differ between the groups, with the exception of the number of harvested lymph nodes (P=.001). The disease-free survival was better in the group that underwent infrarenal para-aortic lymphadenectomy than the group that did not (P=.017); however, the 2 groups did not differ with respect to overall survival (P=.115). Conclusion: We suggest that laparoscopic transperitoneal infrarenal lymphadenectomy for cervical cancer is feasible and safe. The rate of positive lymph nodes in infrarenal lymphadenectomy is very rare in patients with locally advanced cervical carcinoma. Infrarenal lymphadenectomy in patients with cervical cancer did not provide additional survival benefits in this study.
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Park JW, Jang AN, Song JH, Park CY, Lee YS. Electronic structure of Zn doped Fe3O4 thin films. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2013; 13:1895-1898. [PMID: 23755615 DOI: 10.1166/jnn.2013.6996] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We investigated the effect of Zn doping on the electronic property of magnetite by using optical spectroscopy. The (Zn(x)Fe(1-x))Fe2O4 (ZFFO) (x = 0, 0.2, 0.4, and 0.5) samples were prepared by PLD technique. The XRD measurement revealed that all the samples have an inverse spinel-type of crystalline structure. The M-H curves indicate that the saturation magnetization reduces with the increasing x. From the spectroscopic ellipsometry and infrared spectroscopy, we found that the doping of nonmagnetic Zn2+ ions leads to the dramatic change in the electronic structure of the ZFFO films. We discuss the correlation of our spectra with the electric and magnetic properties of the ZFFO films.
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Kim DH, Lee DJ, Park JW, Lee YS. Synthesis and optical characterization of SrHfO3 nano-crystals synthesized by using the combustion method. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2013; 13:1845-1847. [PMID: 23755603 DOI: 10.1166/jnn.2013.6988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We synthesized SrHfO3 nano-crystals (NCs) by using the combustion method, and investigated their emission property using 325 nm photo-excitation. The as-grown SrHfO3 NCs were annealed at different temperatures from 700 degrees C to 1450 degrees C. The X-ray diffraction analysis revealed that all the samples are of a single phase, and the grain size increases with the higher temperature annealing. Interestingly, it is found that in contrast to the bulk case, the SrHfO3 NCs show a strong blue emission even at room temperature. The strong dependence of the visible emission on annealing temperatures and grain sizes indicated that the effects of grain size and oxygen vacancies may play a role in forming the observed visible emission band for SrHfO3 NCs. We also compare our findings with the case of similar material, SrZrO3.
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93
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Yoon SY, Kim TB, Baek S, Kim S, Kwon HS, Lee YS, Lee T, Jang AS, Chang YS, Cho SH, Choi BW, Park JW, Nham DH, Yoon HJ, Cho YJ, Park CS, Moon HB, Cho YS. The impact of total antioxidant capacity on pulmonary function in asthma patients. Int J Tuberc Lung Dis 2013; 17:1036-42. [PMID: 23044449 DOI: 10.5588/ijtld.12.0842] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Oxidative stress, mediated by an imbalance between oxidants and antioxidants, contributes significantly to the pathogenesis of asthma. OBJECTIVE To evaluate the impact of serum total antioxidant capacity (TAC) on the pulmonary function of Korean asthma patients. METHOD A total of 104 adult asthma patients enrolled from the COREA (Cohort for Reality and Evolution of Adult Asthma in Korea) programme participated in the study. Baseline clinical parameters at enrolment, and the results of pulmonary function tests at baseline and 1 and 2 years after enrolment were collected. TAC at baseline was measured using a Trolox-equivalent antioxidant capacity assay. Patients were divided into two groups based on TAC levels, and various clinical parameters were compared. RESULT Serum TAC levels correlated with forced expiratory volume in 1 second (FEV(1)) at baseline (r = 0.22, P = 0.03). The group with higher baseline TAC levels maintained greater mean FEV(1) both 1 and 2 years after enrolment, even after adjusting for sex, age, height, weight, body mass index and smoking status. CONCLUSION These results suggest an important link between serum TAC levels and pulmonary function, indicating that higher TAC levels may be a biomarker for favourable prognosis in asthma patients.
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94
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Hong DG, Park NY, Chong GO, Cho YL, Park IS, Jeong MJ, Park JY, Lee YS. The correlation between expression of synuclein-gamma, glucose transporter-1, and survival outcomes in endometrioid endometrial carcinoma. EUR J GYNAECOL ONCOL 2013; 34:128-131. [PMID: 23781582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PURPOSE To evaluate the correlation between immunohistochemical expression of synuclein-gamma, glucose transporter-1, and survival outcomes in endometrioid endometrial carcinoma. MATERIALS AND METHODS A tissue microarray was constructed using formalinfixed, paraffin-embedded tissue that included 23 early and 18 advanced cases. The intensity and area of the immunohistochemical reactions were evaluated using the semi-quantitative scoring system. RESULTS Synuclein-y expression was higher in the advanced stage, although it was not statistically significant (p = 0.51). Glucose transporter-1 was overexpressed in the advanced stage (p = 0.01). Synuclein-gamma (score = 0 vs > 0) and glucose transporter-1 (score < or = 7 vs > 7) did not show any differences in overall survival (p = 0.54, p = 0.48) and disease-free survival (p = 0.61, p = 0.14). CONCLUSION In this study the expression of synuclein-y and glucose transporter-1 were not considered to be a prognostic factor and were not related with survival outcomes in endometrioid endometrial carcinoma.
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95
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Ryoo SM, Kim WY, Sohn CH, Seo DW, Oh BJ, Lee JH, Lee YS, Lim KS. Factors promoting the prolonged shedding of the pandemic (H1N1) 2009 influenza virus in patients treated with oseltamivir for 5 days. Influenza Other Respir Viruses 2012; 7:833-7. [PMID: 23279949 PMCID: PMC5781218 DOI: 10.1111/irv.12065] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/29/2012] [Indexed: 12/01/2022] Open
Abstract
Background The duration of viral shedding is an important determinant of infectivity and transmissibility and provides vital information for effective infection prevention and control. However, few studies have evaluated viral shedding in patients admitted to hospital with 2009 H1N1 influenza and treated with oseltamivir. Objective To determine the incidence of prolonged 2009 H1N1 influenza viral shedding in patients treated for 5 days with oseltamivir and to identify factors that promote prolonged viral shedding. Methods This was a prospective, observational cohort study of 173 patients infected with 2009 H1N1 influenza (confirmed by RT‐PCR) who were admitted to isolation rooms in the emergency department of our hospital between August 25, 2009 and December 31, 2009. All of the patients were treated according to institutional protocols and received routine follow‐up RT‐PCR testing after 5 days of oseltamivir therapy. Prolonged viral shedding was defined as a positive follow‐up RT‐PCR result. Result Of the 173 patients in our cohort, 88 (50·8%) showed persistent viral shedding after oseltamivir treatment. Viral shedding was significantly prolonged if antiviral therapy was started ≥2 days after symptom onset (OR 2·74, 95% CI 1·29–5·82), if there were major comorbidities (OR 3·07, 95% CI 1·29–7·32), and/or if respiratory symptoms were still present on the day 5 of antiviral treatment (OR 4·13, 95% CI 2·10–8·11). Conclusions The presence of major comorbidities, a delay in initiating antiviral treatment, and continuing respiratory symptoms after 5 days of antiviral treatment are associated with prolonged shedding of the 2009 H1N1 influenza virus.
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96
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Singh DK, Lee YS. Nonconventional spin glass transition in a chemically ordered pyrochlore. PHYSICAL REVIEW LETTERS 2012; 109:247201. [PMID: 23368369 DOI: 10.1103/physrevlett.109.247201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Indexed: 06/01/2023]
Abstract
We report on the study of unusual spin glass properties in the geometrically frustrated pyrochlore Tb(2)Mo(2)O(7), T(g) ~/= 24 K. The analysis of the nonlinear part of dc and complex susceptibilities, near the glass transition regime, suggests the existence of a statistical distribution of relaxation times in short-range ordered ferromagnetic clusters. In addition, the magnetic spins are not sufficiently frozen below the glass transition temperature, which is apparently responsible for the nonequilibrium scaling behavior of the static critical exponents of nonlinear susceptibilities. Our report is expected to shed new light in understanding the freezing properties of frustrated pyrochlores with short-range ferromagnetic interactions.
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97
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Hsu CC, Chang HY, Huang MC, Hwang SJ, Yang YC, Lee YS, Shin SJ, Tai TY. HbA1c variability is associated with microalbuminuria development in type 2 diabetes: a 7-year prospective cohort study. Diabetologia 2012; 55:3163-72. [PMID: 22923064 DOI: 10.1007/s00125-012-2700-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 07/25/2012] [Indexed: 12/16/2022]
Abstract
AIMS/HYPOTHESIS HbA(1c) variability has been shown to be an independent risk factor for nephropathy in patients with type 1 diabetes. In this study, we aimed to explore the association between HbA(1c) variability and microalbuminuria development in patients with type 2 diabetes. We also intended to test the applicability of serially measured HbA(1c) over 2 years for this risk assessment. METHODS Between 2003 and 2005, we recruited 821 middle-aged normoalbuminuric individuals with type 2 diabetes and followed them through to the end of 2010. The average follow-up time was 6.2 years. We defined microalbuminuria as a urine albumin to creatinine ratio of 30 mg/g (3.4 mg/mmol) or higher. HbA(1c) variability was calculated by the SD of serially measured HbA(1c). The Cox proportional hazards model was used to evaluate the association between HbA(1c) SD quartile and development of microalbuminuria. RESULTS The incidence of microalbuminuria for the overall population was 58.4, 58.6, 60.8 and 91.9 per 1,000 person-years for Q1- to Q4-adjusted HbA(1c) SD, respectively (p for trend = 0.042). Compared with patients in Q1, those in Q4 were about 37% more likely to develop microalbuminuria. The HR derived from a series of 2 year HbA(1c) measurements was similar to that from data collection for longer than 4 years. CONCLUSIONS/INTERPRETATION In addition to mean HbA(1c) values, HbA(1c) variability, even measured as early as 2 years, is independently associated with the development of microalbuminuria in patients with type 2 diabetes.
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98
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Wang YH, Hsieh D, Sie EJ, Steinberg H, Gardner DR, Lee YS, Jarillo-Herrero P, Gedik N. Measurement of intrinsic dirac fermion cooling on the surface of the topological insulator Bi2Se3 using time-resolved and angle-resolved photoemission spectroscopy. PHYSICAL REVIEW LETTERS 2012; 109:127401. [PMID: 23005985 DOI: 10.1103/physrevlett.109.127401] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Indexed: 06/01/2023]
Abstract
We perform time- and angle-resolved photoemission spectroscopy of a prototypical topological insulator (TI) Bi(2)Se(3) to study the ultrafast dynamics of surface and bulk electrons after photoexcitation. By analyzing the evolution of surface states and bulk band spectra, we obtain their electronic temperature and chemical potential relaxation dynamics separately. These dynamics reveal strong phonon-assisted surface-bulk coupling at high lattice temperature and total suppression of inelastic scattering between the surface and the bulk at low lattice temperature. In this low temperature regime, the unique cooling of Dirac fermions in TI by acoustic phonons is manifested through a power law dependence of the surface temperature decay rate on carrier density.
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Oh YC, Kang OH, Kim SB, Mun SH, Park CB, Kim YG, Kim YI, Lee YS, Han SH, Keum JH, Shin DW, Ma JY, Kwon DY. Anti-inflammatory effect of sinomenine by inhibition of pro-inflammatory mediators in PMA plus A23187-stimulated HMC-1 Cells. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2012; 16:1184-1191. [PMID: 23047501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
BACKGROUND AND OBJECTIVES Sinomenine is an alkaloid compound and a prominent anti-inflammatory agent found in the root of the climbing plant Sinomenium acutum. However, its effects on the mechanism of human mast cell line (HMC)-1-mediated inflammation remained unknown. MATERIALS AND METHODS To provide insight into the biological effects of sinomenine, we examined its influence on the pro-inflammatory cytokine production in HMC-1 cells stimulated by phorbol 12-myristate-13-acetate (PMA) plus A23187 by evaluating the stimulated cells in the presence or absence of sinomenine. In the present study, the pro-inflammatory cytokine production was measured using ELISA, Reverse Transcription-polymerase chain reaction (RT-PCR) and nuclear factor (NF)-kappaB, mitogen-activated protein kinases (MAPKs) pathway activation, as determined by Western blot analysis. Also, cyclooxygenase (COX)-2 expression was measured through Western blot and RT-PCR analysis. RESULTS Sinomenine inhibited the pro-inflammatory cytokine production induced by PMA plus A23187 in a dose-dependent manner. Furthermore, sinomenine inhibited the phosphorylations of extracellular signal-regulated kinase (ERK) and p38 MAPKs as well as the translocation of NF-kappaB p65 through reduced IkappaBalpha degradation. In addition, sinomenine suppressed COX-2 protein and mRNA expression dose-dependently. CONCLUSIONS Taken together, the results of this study indicate that the anti-inflammatory effects of sinomenine may occur via the inhibition of pro-inflammatory cytokine and COX-2 production through the inhibition of MAPKs and NF-kappaB pathway activation by PMA plus A23187 stimulation in HMC-1 cells.
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Kunkeaw N, Jeon SH, Lee K, Johnson BH, Tanasanvimon S, Javle M, Pairojkul C, Chamgramol Y, Wongfieng W, Gong B, Leelayuwat C, Lee YS. Cell death/proliferation roles for nc886, a non-coding RNA, in the protein kinase R pathway in cholangiocarcinoma. Oncogene 2012; 32:3722-31. [PMID: 22926522 DOI: 10.1038/onc.2012.382] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 07/09/2012] [Accepted: 07/23/2012] [Indexed: 12/25/2022]
Abstract
We have recently identified nc886 (pre-miR-886 or vtRNA2-1) as a novel type of non-coding RNA that inhibits activation of protein kinase R (PKR). PKR's pro-apoptotic role through eukaryotic initiation factor 2 α (eIF2α) phosphorylation is well established in the host defense against viral infection. Paradoxically, some cancer patients have elevated PKR activity; however, its cause and consequence are not understood. Initially, we evaluated the expression of nc886, PKR and eIF2α in non-malignant cholangiocyte and cholangiocarcinoma (CCA) cells. nc886 is repressed in CCA cells and this repression is the cause of PKR's activation therein. nc886 alone is necessary and sufficient for suppression of PKR via direct physical interaction. Consistently, artificial suppression of nc886 in cholangiocyte cells activates the canonical PKR/eIF2α cell death pathway, suggesting a potential significance of the nc886 suppression and the consequent PKR activation in eliminating pre-malignant cells during tumorigenesis. In comparison, active PKR in CCA cells does not induce phospho-eIF2α nor apoptosis, but promotes the pro-survival nuclear factor-κB pathway. Thus, PKR has a dual life or death role during tumorigenesis. Similarly to the CCA cell lines, nc886 tends to be decreased but PKR tends to be activated in our clinical samples from CCA patients. Collectively from our data, we propose a tumor surveillance model for nc886's role in the PKR pathway during tumorigenesis.
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