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Lee SN, Kim HS, An JY, Amaresh S, Lee YG, Nam KW, Lee YS. Preparation and characterization of chlorine doped Li3V2(PO4)3 as high rate cathode active material for lithium secondary batteries. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2014; 14:7516-7520. [PMID: 25942818 DOI: 10.1166/jnn.2014.9560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Monoclinic Li3V2(PO4)2.99Cl0.01 was synthesized using the conventional solid state method and the X-ray diffraction pattern was indexed based on P2(1)/n space group. The sharp cyclic voltammetric curves clearly revealed three lithium extraction/insertion processes at approximately 3.64, 3.72, 4.13, and 4.58 V during the anodic scan and 3.96, 3.58, and 3.48 V during the cathodic scan. Charge/discharge studies showed reduced electrolyte decomposition contribution in the case of the chlorine doped Li3V2(PO4)2.99Cl0.01 sample with an initial capacity of 176 mA h g(-1) at a 0.1 C current rate. The chlorine doped Li3V2(PO4)3 sample showed an increased capacity retention with an increase in current rate, even at a very high C-rate (20 C), than the pristine and carbon coated samples. The pristine and carbon coated Li3V2(PO4)3 samples showed a lower capacity retention of 71% and 84%, respectively, at a current rate of 0.1 C. In contrast, the chlorine doped Li3V,(PO4)3 sample retained 87% of the initial capacity (176 mA h g(-1)) at the same current rate but with a higher coulombic efficiency of 91%. The enhanced capacity retention for the chlorine doped Li3V2(PO4)3 was attributed to the reduction in polarization and decreased charge transfer resistance of the electrode.
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Sun CH, Lew T, Tan D, Hoi SY, Khandan R, Poi CH, Surender R, Tay S, Wan G, Lee YS, Lim LL, Solikin H, Yeak S. Paperless reporting and electronically verifying clinical investigations. Int J Health Care Qual Assur 2014; 27:382-90. [PMID: 25087336 DOI: 10.1108/ijhcqa-12-2012-0124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE The purpose of this paper is to outline considerations and steps taken to introduce electronic reporting and verification from systems design and multidisciplinary collaborations to gap analysis and devising solutions. It also evaluates carefully placed forcing functions' impact on verification rates. DESIGN/METHODOLOGY/APPROACH A multidisciplinary workgroup was formed to stop print and establish electronic reporting. The electronic verification's success was assessed by weekly activity analysis. FINDINGS Introducing a verification forcing function markedly improved verification activity. Thereafter, non-verified results stabilized at 7 percent up to 75 weeks post-implementation. PRACTICAL IMPLICATIONS This paper illustrates how results reporting and verification could be implemented in a tertiary hospital using a mixed electronic and paper record. Factors that were critical to success include stakeholder engagement and applying systems design that focussed on patient safety as a key priority. The electronic reporting system was augmented by strategically inserted forcing functions, clear clinical-responsibility lines and ancillary alert systems. ORIGINALITY/VALUE The systems design method's value in managing non-critical but abnormal results appears to have been under-appreciated. This paper describes how systems design could be used to improve health information delivery and management.
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An J, Shim JH, Kim SO, Lee D, Kim KM, Lim YS, Lee HC, Chung YH, Lee YS. Prevalence and prediction of coronary artery disease in patients with liver cirrhosis: a registry-based matched case-control study. Circulation 2014; 130:1353-62. [PMID: 25095888 DOI: 10.1161/circulationaha.114.009278] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND There is conflict regarding the prevalence of coronary artery disease (CAD) in patients with liver cirrhosis. This study aimed to investigate the prevalence of silent CAD in comparison with the general population, and to identify the relevant risk factors in patients with liver cirrhosis. METHODS AND RESULTS This retrospective study included 1045 prospectively registered consecutive patients with liver cirrhosis without any history of chest pain or CAD, who underwent computerized coronary angiography as a pretransplant workup. These were matched with 6283 controls with healthy livers, based on propensity scores according to established cardiovascular risk factors. Obstructive CAD was defined as ≥50% luminal narrowing in any artery. A matched analysis of 853 pairs showed that the proportion of subjects with obstructive CAD did not differ significantly between the cirrhotic and control groups (7.2% versus 7.9%, P=0.646), in agreement with the outcome of multivariate analysis for its predictors, with an adjusted odds ratio for liver cirrhosis of 1.06 (P=0.690). Nonobstructive CAD was more prevalent in the matched cirrhotic cases (30.6% versus 23.4%, P=0.001). In the pooled cirrhotic cohort, older age, male sex, hypertension, diabetes mellitus, and alcoholic cirrhosis were independently associated with obstructive CAD (adjusted odds ratios, 1.07, 2.74, 1.69, 2.37, and 2.17, respectively; P<0.05 for all), whereas liver function and coagulation parameters were not. CONCLUSIONS Asymptomatic cirrhotic patients and nonhepatic subjects are similar in terms of the prevalence of occult obstructive CAD. Traditional cardiovascular risk factors are related to critical coronary stenosis in cirrhotic patients, and thus may be helpful indicators for more careful preoperative evaluation of coronary risk.
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Kim GA, Lim YS, An J, Lee D, Shim JH, Kim KM, Lee HC, Chung YH, Lee YS, Suh DJ. HBsAg seroclearance after nucleoside analogue therapy in patients with chronic hepatitis B: clinical outcomes and durability. Gut 2014; 63:1325-32. [PMID: 24162593 DOI: 10.1136/gutjnl-2013-305517] [Citation(s) in RCA: 279] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Little is known about the long-term clinical outcome and durability of HBsAg seroclearance following nucleos(t)ide analogue (NUC) therapy in patients with chronic hepatitis B (CHB). DESIGN During a median follow-up period of 6 years (33 567 patient-years) of 5409 CHB patients who were initially treated with lamivudine or entecavir, a total of 110 achieved HBsAg seroclearance (0.33% annual seroclearance rate) and were included in this study. RESULTS Baseline alanine aminotransferase (ALT) level >5 times of upper limit of normal was associated with higher probability of HBsAg seroclearance (HR 1.80, p<0.01), while HBeAg positivity (HR 0.46, p<0.01), high HBV DNA level (log(10) IU/mL; HR 0.61, p<0.01), and cirrhosis (HR 0.48, p<0.01) were inversely associated with the probability of HBsAg seroclearance by multivariable analysis. During follow-up for 287 patient-years after HBsAg seroclearance, only two patients with baseline cirrhosis developed hepatocellular carcinoma (HCC) or died (0.7% annual risk), which was of a significantly lower rate compared with propensity score-matched patients without HBsAg seroclearance (HR 0.09, p<0.01). HBsAg reversion and/or HBV DNA reversion occurred in 18 patients, most of which were transient with extremely low serum levels of HBsAg (0.05-1.00 IU/mL) and HBV DNA (17-1818 IU/mL). None required retreatment. The cumulative probability of anti-HBs seroconversion (detection of anti-HBs) at 4 years was 67.4% by Kaplan-Meier analysis. Selection for lamivudine-resistance HBV mutants during treatment was not associated with composite reversion (p=0.66). CONCLUSIONS HBsAg seroclearance achieved after NUC treatment was associated with favourable clinical outcomes and was durable in most cases during long-term follow-up.
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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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Heo NY, Lim YS, Lee W, Oh M, An J, Lee D, Shim JH, Kim KM, Lee HC, Lee YS, Suh DJ. No association between the IL28B SNP and response to peginterferon plus ribavirin combination treatment in Korean chronic hepatitis C patients. Clin Mol Hepatol 2014; 20:177-84. [PMID: 25032184 PMCID: PMC4099333 DOI: 10.3350/cmh.2014.20.2.177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 06/10/2014] [Accepted: 06/12/2014] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND/AIMS There are few available data regarding the association between the single nucleotide polymorphisms (SNPs) of the gene encoding interleukin 28B (IL28B) and a sustained virologic response (SVR) to peginterferon (PEG-IFN) plus ribavirin (RBV) therapy in Korean chronic hepatitis C patients. METHODS This was a retrospective cohort study of 156 patients with chronic hepatitis C virus (HCV) infection who received combination treatment of PEG-IFN plus RBV. Blood samples from these patients were analyzed to identify the IL28B SNPs at rs12979860, rs12980275, rs8099917, and rs8103142. Association analyses were performed to evaluate the relationships between each IL28B SNP and SVRs. RESULTS Seventy six patients with HCV genotype 1 and 80 with genotype non-1 were enrolled. The frequencies of rs12979860 CC and CT genotypes were 90.4% and 9.6%, respectively; those of rs12980275 AA and AG genotypes were 87.2% and 12.8%, respectively; those of rs8099917 TT and TG genotypes were 92.3% and 7.7%, respectively; and those of rs8103142 TT and CT genotypes were 90.4% and 9.6%, respectively. Among the patients with HCV genotype 1, the SVR rates were 69.7% and 80.0% for rs12979860 CC and CT, respectively (P=0.71). Among the HCV genotype non-1 patients, SVR rates were 88.0% and 100% for rs12979860 CC and CT (P=1.00), respectively. CONCLUSIONS Genotypes of the IL28B SNP that are known to be favorable were present in most of the Korean patients with chronic hepatitis C in this study. Moreover, the IL28B SNP did not influence the SVR rate in either the HCV genotype 1 or non-1 patients. Therefore, IL28B SNP analysis might be not useful for the initial assessment, prediction of treatment outcomes, or treatment decision-making of Korean chronic hepatitis C patients.
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Choi J, Shim JH, Park DH, Lee SS, Seo DW, Lee SK, Kim MH, Kim KM, Lim YS, Chung YH, Lee YS, Suh DJ, Lee HC. Clinical usefulness of endoscopic palliation in patients with biliary obstruction caused by hepatocellular carcinoma. Digestion 2014; 88:87-94. [PMID: 23941887 DOI: 10.1159/000353200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 05/23/2013] [Indexed: 02/04/2023]
Abstract
BACKGROUND/AIMS To evaluate the clinical usefulness of endoscopic biliary drainage (EBD) in patients with hepatocellular carcinoma (HCC). METHODS A total of 111 jaundiced patients underwent attempted EBD for relief of HCC-related biliary stricture at our hospital over a 5-year period and all were included in the intention-to-treat (ITT) analysis. RESULTS After an endoscopic attempt at drainage, 46 (41.4%) of the 111 patients achieved a favorable response. Biliary cannulation failed in 5 patients. Child-Pugh class C, portal vein thrombosis and severe hyperbilirubinemia were negatively correlated with a favorable EBD response. In the ITT population, 40 (87.0%) of the favorable responders received further treatment for HCC, >2 (3.1%) of the unfavorable responders (p < 0.001). The median survival time for ITT patients with and without a favorable response to EBD was 8.7 and 1.3 months, respectively (p < 0.001). Cox's model showed that a favorable EBD response was an independent predictor of longer survival (hazard ratio 0.20, p < 0.001). CONCLUSIONS For HCC patients with tumor-related biliary obstruction, predictors of effective endoscopic palliation of cholestasis were relatively mild hyperbilirubinemia and preserved liver function and intact portal vein flow. A favorable EBD response was associated with longer survival outcomes.
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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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Yang JE, Park E, Lee HJ, Kang HJ, Kim KM, Yu E, Lee D, Shim JH, Lim YS, Lee HC, Chung YH, Lee YS. Role of 15-hydroxyprostaglandin dehydrogenase down-regulation on the prognosis of hepatocellular carcinoma. Clin Mol Hepatol 2014; 20:28-37. [PMID: 24757656 PMCID: PMC3992327 DOI: 10.3350/cmh.2014.20.1.28] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 01/21/2014] [Accepted: 02/11/2014] [Indexed: 01/22/2023] Open
Abstract
Background/Aims The role of prostaglandin E2 (PGE2) in the modulation of cell growth is well established in colorectal cancer. The aim of this study was to elucidate the significance of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) down-regulation on the prognosis of hepatocellular carcinoma (HCC) patients. Methods The expression of 15-PGDH in HCC cell lines and resected HCC tissues was investigated, and the correlation between 15-PGDH expression and HCC cell-line proliferation and patient survival was explored. Results The interleukin-1-β-induced suppression of 15-PGDH did not change the proliferation of PLC and Huh-7 cells in the MTS [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The induction of 15-PGDH by transfection in HepG2 cells without baseline 15-PGDH expression was suppressed at day 2 of proliferation compared with empty-vector transfection, but there was no difference at day 3. Among the 153 patients who received curative HCC resection between 2003 and 2004 at our institution, 15-PGDH expression was observed in resected HCC tissues in 56 (36.6%), but the 5-year survival rate did not differ from that of the remaining 97 non-15-PGDH-expressing patients (57.1% vs 59.8%; P=0.93). Among 50 patients who exhibited baseline 15-PGDH expression in adjacent nontumor liver tissues, 28 (56%) exhibited a reduction in 15-PGDH expression score in HCC tissues, and there was a trend toward fewer long-term survivors compared with the remaining 22 with the same or increment in their 15-PGDH expression score in HCC tissues. Conclusions The prognostic significance of 15-PGDH down-regulation in HCC was not established in this study. However, maintenance of 15-PGDH expression could be a potential therapeutic target for a subgroup of HCC patients with baseline 15-PGDH expression in adjacent nontumor liver tissue.
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Park W, Chung YH, Kim JA, Jin YJ, Lee D, Shim JH, Lee D, Kim KM, Lim YS, Lee HC, Lee YS, Kim PN, Sung KB. Recurrences of hepatocellular carcinoma following complete remission by transarterial chemoembolization or radiofrequency therapy: Focused on the recurrence patterns. Hepatol Res 2013; 43:1304-12. [PMID: 23442052 DOI: 10.1111/hepr.12083] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 01/15/2013] [Accepted: 01/23/2013] [Indexed: 12/12/2022]
Abstract
AIM In this study, we analyzed the rates and patterns of recurrences in hepatocellular carcinoma (HCC) patients who had achieved complete remission (CR) by transarterial chemoembolization (TACE) or radiofrequency ablation (RFA), and also examined the differences of recurrence patterns between TACE-treated and RFA-treated groups. METHODS We followed 309 consecutive HCC patients who achieved CR following TACE (n = 220) or RFA (n = 89) for a median of 68 months. Recurrence patterns were classified as local recurrence and secondary tumor according to location of recurrence (≤2 cm and >2 cm from primary tumor). RESULTS Recurred HCC had been found in 231 out of 309 patients (75%) with CR by TACE or RFA; 112 local recurrences (48%), 100 secondary tumor (43%) and 19 both (9%). The cumulative recurrence rates at 1, 3 and 5 years were 22%, 64% and 79%, respectively. The overall recurrences at 1, 3 and 5 years following CR in the TACE-treated group was not different from those in the RFA-treated group (21%, 68% and 81% vs 26%, 56% and 84%, respectively; P = NS) However, the cumulative occurrence rates of local recurrence rates at 1, 3 and 5 years were significantly higher in the TACE-treated group compared to the RFA-treated group (15%, 53% and 65% vs 15%, 27% and 34%, respectively; P = 0.001). CONCLUSION Recurrence of HCC is very common, even following CR by TACE or RFA. Especially, local recurrences are very frequent in cases who achieved CR by TACE, which suggests that additional ablation therapy may be beneficial to prevent recurrences following CR by TACE.
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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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Yoon SM, Lim YS, Park MJ, Kim SY, Cho B, Shim JH, Kim KM, Lee HC, Chung YH, Lee YS, Lee SG, Lee YS, Park JH, Kim JH. Stereotactic body radiation therapy as an alternative treatment for small hepatocellular carcinoma. PLoS One 2013; 8:e79854. [PMID: 24255719 PMCID: PMC3821847 DOI: 10.1371/journal.pone.0079854] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 09/25/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Even with early stage hepatocellular carcinoma (HCC), patients are often ineligible for surgical resection, transplantation, or local ablation due to advanced cirrhosis, donor shortage, or difficult location. Stereotactic body radiation therapy (SBRT) has been established as a standard treatment option for patients with stage I lung cancer, who are not eligible for surgery, and may be a promising alternative treatment for patients with small HCC who are not eligible for curative treatment. MATERIALS AND METHODS A registry database of 93 patients who were treated with SBRT for HCC between 2007 and 2009 was analyzed. A dose of 10-20 Gy per fraction was given over 3-4 consecutive days, resulting in a total dose of 30-60 Gy. The tumor response was determined using dynamic computed tomography or magnetic resonance imaging, which was performed 3 months after completion of SBRT. RESULTS The median follow-up period was 25.6 months. Median size of tumors was 2 cm (range: 1-6 cm). Overall patients' survival rates at 1 and 3 years were 86.0% and 53.8%, respectively. Complete and partial tumor response were achieved in 15.5% and 45.7% of patients, respectively. Local recurrence-free survival rate was 92.1% at 3 years. Most local failures were found in patients with HCCs > 3 cm, and local control rate at 3 years was 76.3% in patients with HCC > 3 cm, 93.3% in patients with tumors between 2.1-3 cm, and 100% in patients with tumors ≤ 2 cm, respectively. Out-of-field intrahepatic recurrence-free survival rates at 1 and 3 years were 51.9% and 32.4%, respectively. Grade ≥ 3 hepatic toxicity was observed in 6 (6.5%). CONCLUSIONS SBRT was effective in local control of small HCC. SBRT may be a promising alternative treatment for patients with small HCC which is unsuitable for other curative therapy.
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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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Lim YS, Lee JY, Lee D, Shim JH, Lee HC, Lee YS, Suh DJ. Randomized trial of the virologic response during up to two years of entecavir-adefovir combination therapy in multiple-drug-refractory chronic hepatitis B virus patients. Antimicrob Agents Chemother 2013; 57:3369-74. [PMID: 23650172 PMCID: PMC3697381 DOI: 10.1128/aac.00587-13] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 04/30/2013] [Indexed: 02/07/2023] Open
Abstract
A 1-year trial with entecavir plus adefovir resulted in a rate of virological response (VR) higher than that seen with lamivudine plus adefovir in multiple-drug-refractory chronic hepatitis B (CHB) patients. This extension study enrolled 89 of 90 patients who completed a 52-week randomized trial comparing treatment with entecavir plus adefovir (EA) to treatment with lamivudine plus adefovir (LA). At the baseline of the original study, all patients had lamivudine-resistant hepatitis B virus (HBV) and serum HBV DNA > 2,000 IU/ml despite prior lamivudine plus adefovir therapy. Of the 89 enrolled patients, 45 initially randomized to receive entecavir plus adefovir and the other 44 randomized to receive lamivudine plus adefovir received entecavir plus adefovir for an additional 52 weeks (EA-EA and LA-EA, respectively). The proportions of patients with a VR (serum HBV DNA < 60 IU/ml) gradually increased in both groups and were comparable at week 104 (42.2% in the EA-EA group and 34.1% in the LA-EA group; P = 0.51). The mean reductions in serum HBV DNA from baseline in the two groups were similar (-2.8 log10 IU/ml and -2.8 log10 IU/ml, respectively; P = 0.87). At week 104, the number of patients who retained the preexisting HBV mutants resistant to adefovir or entecavir had decreased from 8 to 2 in the EA-EA group and from 15 to 6 in the LA-EA group (P = 0.27). Both study groups had favorable safety profiles. In conclusion, up to 104 weeks of entecavir plus adefovir treatment was associated with a progressive VR, a decrease of levels of preexisting drug-resistant mutants, and no selection for additional resistance mutants of HBV in multiple-drug-refractory CHB patients. (This study has been registered at ClinicalTrials.gov under registration no. NCT01023217.).
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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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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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Heo NY, Lim YS, Lee HC, Lee YS, Kim KM, Byun KS, Han KH, Lee KS, Paik SW, Yoon SK, Suh DJ. High effectiveness of peginterferon alfa-2a plus ribavirin therapy in Korean patients with chronic hepatitis C in clinical practice. Clin Mol Hepatol 2013; 19:60-9. [PMID: 23593611 PMCID: PMC3622857 DOI: 10.3350/cmh.2013.19.1.60] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 12/27/2012] [Accepted: 01/10/2013] [Indexed: 02/07/2023] Open
Abstract
Background/Aims Identifying the impact of a patient's ethnicity on treatment responses in clinical practice may assist in providing individualized treatment regimens for chronic hepatitis C (CHC). The effectiveness of standard peginterferon plus ribavirin therapy and the need for triple combination therapy with protease inhibitors in Koreans remain matters of debate. These issues were investigated in the present study. Methods The clinical data of 272 treatment-naïve Korean CHC patients who were treated in a community-based clinical trial (Clinical Trial group; n=51) and in clinical practice (Cohort group; n=221), were analyzed and compared. All were treated with standard protocols of peginterferon alfa-2a plus ribavirin therapy. Results For patients with hepatitis C virus (HCV) genotype 1, the sustained virological response (SVR) rates in the Clinical Trial and Cohort groups were 81% (21/26) and 55% (58/106), respectively, by intention-to-treat (ITT) analysis (P=0.02), and 100% (13/13) and 80% (32/40), respectively, in treatment-adherent patients (P=0.18). For patients with HCV genotype 2, the SVR rates in these two groups were 96% (24/25) and 88% (101/115), respectively, by ITT analysis (P=0.31). Adherence and treatment duration were independent predictors of SVR for genotypes 1 and 2, respectively (P<0.01 for each). Korean patients with CHC achieved high SVR rates with peginterferon alfa-2a plus ribavirin in both the clinical trial and clinical practice settings. Conclusions Measures to raise adherence to standard therapy in clinical practice may improve the SVR rates in these patients as effectively as adding protease inhibitors, thus obviating the need for the latter.
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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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