Jung-Eun Choi

Korea University, Seoul, Seoul, South Korea

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Publications (55)154.3 Total impact

  • Article: Hyaluronic Acid - Gold Nanoparticle / Interferon α Complex for Targeted Treatment of Hepatitis C Virus Infection.
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    ABSTRACT: Gold nanoparticles (AuNPs) have been extensively investigated as an emerging delivery carrier of various biopharmaceuticals. Instead of non-specific polyethylene glycol (PEG) conjugated interferon α (IFNα) for the clinical treatment of hepatitis C virus (HCV) infection, in this work, target-specific long-acting delivery system of IFNα was successfully developed using the hybrid materials of AuNP and hyaluronic acid (HA). The HA-AuNP/IFNα complex was prepared by chemical binding of thiolated HA and physical binding of IFNα to AuNP. According to anti-proliferation tests in Daudi cells, HA-AuNP/IFNα complex showed a comparable biological activity to PEG-Intron with a highly enhanced stability in human serum. Even 7 days post-injection, HA-AuNP/IFNα complex was target-specifically delivered and remained in the murine liver tissue, whereas IFNα and PEG-Intron were not detected in the liver. Accordingly, HA-AuNP/IFNα complex significantly enhanced the expression of 2',5'-oligoadenylate synthetase 1 (OAS1) for innate immune responses to viral infection in the liver tissue, which was much higher than those by IFNα, PEG-Intron, and AuNP/IFNα complex. Taken together, the target-specific HA-AuNP/IFNα complex was thought to be successfully applied to the systemic treatment of HCV infection.
    ACS Nano 10/2012; · 10.77 Impact Factor
  • Article: Oleuropein reduces free fatty acid-induced lipogenesis via lowered extracellular signal-regulated kinase activation in hepatocytes.
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    ABSTRACT: Oleuropein, a bitter glucoside found in green olive leaves, and its metabolite hydroxytyrosol display powerful antioxidant activity both in vivo and in vitro. In this study, we hypothesized that the antioxidant activity of oleuropein could attenuate hepatic steatosis. To test this hypothesis, we established steatotic hepatocytes using HepG2 and FL83B cells treated with free fatty acids (FFAs) (oleate:palmitate, 2:1). To confirm hepatic steatosis, the intracellular lipid levels were quantitatively measured by Nile Red staining, and the sizes and distributions of lipid droplets were visualized by transmission electron microscopy. The expression of PAT family proteins as well as of adipose differentiation-related protein and tail interacting protein (TIP47) was evaluated by reverse transcriptase polymerase chain reaction and immunoblotting. To examine the cellular and molecular events associated with oleuropein, annexin V/propidium iodide staining and immunoblotting were performed. Oleuropein decreased the number and size of lipid droplets in FFA-treated cells and reduced intracellular triglyceride accumulation. However, it did not affect the expression of lipid droplets-associated PAT family proteins, including adipose differentiation-related protein and TIP47. In addition, oleuropein reduced FFA-induced extracellular signal-regulated kinase activation but had no effect on c-Jun N-terminal kinase or AKT activation. Given its protective effects against FFA-induced hepatocellular steatosis, oleuropein may be a lipid-lowering agent.
    Nutrition research (New York, N.Y.) 10/2012; 32(10):778-86. · 1.20 Impact Factor
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    Article: No association between PAWR gene polymorphisms and tardive dyskinesia in schizophrenia patients.
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    ABSTRACT: Tardive dyskinesia (TD) is a hyperkinetic movement disorder associated with the prolonged use of antipsychotic drugs. Since prostate apoptosis response 4 (Par-4) is a key ligand of the dopamine D2 receptor, the Par-4 gene (PAWR) is a good candidate gene to study in the context of TD susceptibility. We examined the association between PAWR gene polymorphisms and TD. Three single nucleotide polymorphisms of PAWR were selected for the analysis: rs7979987, rs4842318, and rs17005769. Two hundred and eighty unrelated Korean schizophrenic patients participated in this study (105 TD and 175 non-TD patients). Genotype/allele-wise and haplotype-wise analyses were performed. There were no significant differences in genotype and allele frequencies between the two groups. Haplotype analysis also did not reveal a difference between the two groups. Within the limitations imposed by the size of the clinical sample, these findings suggest that PAWR gene variants do not significantly contribute to an increased risk of TD.
    Psychiatry investigation 06/2012; 9(2):191-4. · 0.99 Impact Factor
  • Article: Increased phosphorylation of dynamin-related protein 1 and mitochondrial fission in okadaic acid-treated neurons.
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    ABSTRACT: Mitochondrial dysfunction is a prominent feature of neurodegenerative diseases and aging. A recent study showed that phosphorylation of dynamin-related protein 1 (Drp1) is increased in Alzheimer's disease (AD) brains compared to control brains, indicating that mitochondrial fission is increased in AD brains. Here, we showed that Drp1 phosphorylation and mitochondrial fission were also increased in rat cortical neurons treated with okadaic acid (OA), which inhibits protein phosphatase-2A (PP2A) and induces AD-like tau phosphorylation and neuronal death. Concurrent with this abnormal increase in mitochondrial fission, mitochondrial reactive oxygen species (ROS) were also increased, suggesting mitochondrial damage and detrimental effects on cell survival. Parkin, which is necessary for mitophagy of abnormal mitochondria and has been shown to be decreased in AD brains, and K48-linked polyubiquitin were also decreased in OA-treated neurons, suggesting that the mitophagic process required to degrade detrimental ROS-generating mitochondria is disabled. Collectively, our results demonstrate that abnormal mitochondrial fission, ROS generation, and inefficient mitophagy all occur in PP2A-inhibited neurons, as in AD brains, and suggest that this model could be used in developing inhibitors of mitochondrial fission or ROS generation.
    Brain research 03/2012; 1454:100-10. · 2.46 Impact Factor
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    Article: The efficacy of arm node preserving surgery using axillary reverse mapping for preventing lymphedema in patients with breast cancer.
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    ABSTRACT: The axillary reverse mapping (ARM) technique to identify and preserve arm nodes during sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND) was developed to prevent lymphedema. The purpose of this study was to investigate the location and metastatic rate of the arm node, and to evaluate the short term incidence of lymphedema after arm node preserving surgery. From January 2009 to October 2010, 97 breast cancer patients who underwent ARM were included. Blue-dye (2.5 mL) was injected into the ipsilateral upper-inner arm. At least 20 minutes after injection, SLNB or ALND was performed and blue-stained arm nodes and/or lymphatics were identified. Patients were divided into two groups, an arm node preserved group (70 patients had ALND, 10 patients had SLNB) and an unpreserved group (13 patients had ALND, 4 patients had SLNB). The difference in arm circumference between preoperative and postoperative time points was checked in both groups. The mean number of identified blue stained arm nodes was 1.4±0.6. In the majority of patients (92%), arm nodes were located between the lower level of the axillary vein and just below the second intercostobrachial nerve. In the arm node unpreserved group, 2 patients had metastasis in their arm node. Among ALND patients, in the arm node preserved group, the difference in arm circumference between preoperative and postoperative time points in ipsilateral and contralateral arms was 0.27 cm and 0.07 cm, respectively, whereas it was 0.47 cm and -0.03 cm in the unpreserved group; one case of lymphedema was found after 6 months. No difference was found between arm node preserved and unpreserved group among SLNB patients. Arm node preserving was possible in all breast cancer patients with identifiable arm nodes, during ALND or SLNB, except for those with high surgical N stage, and lymphedema did not develop in patients with arm node preserving surgery.
    Journal of breast cancer. 03/2012; 15(1):91-7.
  • Article: zVLL-CHO at low concentrations acts as a calpain inhibitor to protect neurons against okadaic acid-induced neurodegeneration.
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    ABSTRACT: There is evidence that β-secretase and amyloid precursor protein β-C-terminal fragments (APP-CTF) are involved in the pathogenesis of Alzheimer's disease (AD). Previously, we have reported that N-benzyloxycarbonyl-Val-Leu-leucinal (zVLL-CHO) reduced APP β-CTF accumulation in axonal swellings of degenerating neurons. Here, in an effort to discover more effective neuroprotective agents, we examined the effects of the β-secretase inhibitors, H-KTEEISEVN-stat-VAEF-OH (VAEF) and H-EVNstatineVAEF-NH2 (GL-189) as well as zVLL-CHO on OA (okadaic acid)-induced neurodegeneration. Unexpectedly, we found that pretreatment with zVLL-CHO (1 μM) protected neurons after OA treatment, whereas both VAEF and GL-189 lacked neuroprotective effects. Interestingly, 1 μM zVLL-CHO did not inhibit β-secretase. We previously reported that calpain is activated by OA treatment and calpain inhibitors protect against OA-induced neurodegeneration. The data presented here show that pretreatment with 1 μM zVLL-CHO decreased the levels of calpain-cleaved α-spectrin with a concomitant decrease in LDH release and an increase in average dendritic branch length compared to neurons treated with OA alone. These findings suggest that zVLL-CHO protects against OA-induced neurodegeneration via calpain inactivation.
    Neuroscience Letters 02/2012; 509(1):33-8. · 2.11 Impact Factor
  • Article: RPL36 as a prognostic marker in hepatocellular carcinoma.
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    ABSTRACT: Ribosomal proteins (RP) play key roles in the regulation of apoptosis, multidrug resistance and carcinogenesis. The aim of this study was to investigate the expression of ribosomal protein L36 (RPL36) in hepatocellular carcinoma (HCC) and to correlate it with clinicopathological parameters and clinical outcome. Liver specimens were obtained from 60 HCC patients who had undergone a partial hepatectomy. Expression of RPL36 in tumor tissue and surrounding non-tumorous tissues was evaluated on a tissue microarray by immunohistochemistry. RPL36 was expressed in 45 of 60 (75%) HCC by immunohistochemistry, but was not detected in corresponding non-tumors. RPL36 expression correlated significantly with serum levels of albumin (P= 0.044) and prothrombin time (P= 0.026), which reflect liver synthetic function. Moreover, expression of RPL36 was found to be higher in patients with early tumor stages (I/II) (P= 0.038) or without portal vein thrombosis (P= 0.005). In univariate analysis, patients with RPL36 expression revealed better overall survival (P= 0.037). By multivariate survival analysis, RPL36 expression was found to be an independent prognostic factor for overall survival (P= 0.026). Our data suggest that RPL36 may be involved in the early stage of hepatocarcinogenesis, and it can be used as an independent and potential prognostic marker for resected HCC.
    Pathology International 11/2011; 61(11):638-44. · 1.62 Impact Factor
  • Article: CD133+ liver cancer stem cells modulate radioresistance in human hepatocellular carcinoma.
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    ABSTRACT: CD133 is a cancer stem-cell (CSC) marker associated with radioresistance and chemoresistance in various cancers. In the present study, CD133-expressing liver cancer cells following radiation exposure showed higher activation of MAPK/PI3K signaling pathway and reduction in reactive oxygen species levels compared to CD133- cells. The in vivo study with a xenograft model showed increased tumor formation in irradiated CD133+ cell-injected nude mice compared to the CD133- group, suggesting that CD133 contributes to radioresistance in HCC. Therefore, CD133-expressing liver cancer cells have anti-apoptotic and radioresistance properties that may be useful to improve anti-cancer treatments, including chemotherapy/radiotherapy of HCC.
    Cancer letters 10/2011; 315(2):129-37. · 4.86 Impact Factor
  • Article: Polymorphism near the IL28B gene in Korean hepatitis C virus-infected patients treated with peg-interferon plus ribavirin.
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    ABSTRACT: Single nucleotide polymorphisms (SNPs) near the IL28B gene have recently been described as predictors of antiviral therapy responses in patients with hepatitis C virus (HCV) genotype-1. The aim of this study was to investigate the association between genetic variation near the IL28B gene and treatment outcome prediction in Korean patients receiving peg-interferon (PEG-IFN) plus ribavirin therapy. The allelic discrimination assay by Taqman real-time PCR was developed to determine genotypes of SNPs, rs12979860 and rs8099917, which were analyzed in 65 Korean patients with HCV genotype-1. For rs12979860, the frequency of patients with sustained virological response (SVR) was 70.2% in those with the CC genotype and 25% in those with the CT genotype. Early virological response (EVR) in patients with the CC genotype (84.2%) was higher than in those with the CT genotype (25.0%). For rs8099917, patients with the TT genotype showed significantly higher in SVR and EVR than those with the TG/GG genotype (69.6% vs 33.3% and 82.1% vs 44.4%, respectively). With regards to the genotype frequency of the SNPs, the homozygous genotypes for rs12979860 (CC) or rs8099917 (TT) in Korean patients showed a significantly higher frequency as compared with other ethnicities; Caucasians, African-American, Hispanic, and Japanese. These results demonstrate that the genotypes rs12979860 CC and rs8099917 TT were more frequently observed in Korean patients compared to other ethnicities, and suggest that the genetic characteristics of patients may be prognostic factor that predicts antiviral response to PEG-IFN therapy for chronic hepatitis C.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 09/2011; 52(4):363-6. · 3.12 Impact Factor
  • Article: Cannabinoid type 1 receptor gene polymorphisms are not associated with olanzapine-induced weight gain.
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    ABSTRACT: Olanzapine is an atypical antipsychotic known to cause considerable weight gain. The cannabinoid type 1 receptor has been reported to be involved in energy balance control, appetite stimulation, and increases in body weight. In the present study, we investigated three polymorphisms (rs1049353, rs806368, and rs4707436) in the cannabinoid type 1 receptor gene (CNR1) and weight gain in Korean patients with schizophrenia receiving olanzapine treatment. Weight and height were measured prior to starting olanzapine and again after long-term treatment in 78 patients with schizophrenia. CNR1 polymorphisms were genotyped using PCR-RFLP methods. The three CNR1 polymorphisms were not associated with body weight changes from baseline to the endpoint after olanzapine treatment (p > 0.05). There were also no significant differences in genotype, allele, or haplotype frequencies between the high weight gain (at least 7%) and low weight gain (less than 7%) groups. Within the limitations imposed by the smallness of the clinical sample, our findings suggest that CNR1 polymorphisms are not associated with olanzapine-induced weight gain. Copyright © 2011 John Wiley & Sons, Ltd.
    Human Psychopharmacology Clinical and Experimental 06/2011; 26(4-5):332-7. · 2.48 Impact Factor
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    Article: No Evidence for an Association between Dopamine D2 Receptor Polymorphisms and Tardive Dyskinesia in Korean Schizophrenia Patients.
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    ABSTRACT: Tardive dyskinesia (TD) is a long-term adverse effect of antipsychotic. Dopaminergic activity in the nigrostriatal system have been proposed to be involved in development of TD and dopamine D2 receptors (DRD2) has been regarded as a candidate gene for TD because the antipsychotics have potent antagonism DRD2. This study was aimed to find the relationship between DRD2 gene and antipsychotic-induced TD. We evaluated whether 5 DRD2 single nucleotide polymorphisms (-141Cins>del/TaqID/NcoI/Ser311Cys/TaqIA) are associated with antipsychotic-induced TD in 263 Korean schizophrenia patients with (n=100) and without TD (n=163) who were matched for antipsychotic drug exposure and other relevant variables. Haplotype analyses were also performed. None of 5 polymorphisms were found to be significantly associated with TD and with TD severity as measured by Abnormal Involuntary Movement Scale. Overall haplotype (-141Cins>del/TaqID/NcoI/Ser311Cys/TaqIA) frequency was also not significantly different between TD and non-TD groups, although one rare haplotype (I-D1-T-G-A1) showed significantly different frequency between TD and non-TD groups (2.7% vs. 8.5%, respectively, p=0.031). The present study does not support that DRD2 gene may be involved in TD in the Korean population, although further studies are warranted.
    Psychiatry investigation 03/2011; 8(1):49-54. · 0.99 Impact Factor
  • Article: Silencing of 14-3-3ζ over-expression in hepatocellular carcinoma inhibits tumor growth and enhances chemosensitivity to cis-diammined dichloridoplatium.
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    ABSTRACT: The 14-3-3ζ protein plays a key role in regulation of cellular processes. In the present study, we showed that 14-3-3ζ protein was significantly overexpressed in hepatoma cell lines and human tumorous tissues of hepatocellular carcinoma (HCC) patients. Knockdown with RNA interference in hepatoma cell lines with high 14-3-3ζ expression suppressed tumor cell proliferation via activation of c-Jun N-terminal kinase (JNK) and p38/MAPK. Furthermore, suppression of 14-3-3ζ enhanced the anti-cancer effect of cis-diammined dichloridoplatium (CDDP) in hepatoma cell lines. These results suggest that silencing of 14-3-3ζ may be an attractive target for HCC therapeutic development.
    Cancer letters 02/2011; 303(2):99-107. · 4.86 Impact Factor
  • Article: Subgenotype and genetic variability in the precore/core regions of hepatitis B virus in Korean patients with chronic liver disease.
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    ABSTRACT: The aim of this study was to determine the prevalence of hepatitis B virus (HBV) subgenotypes, the spectrum of mutations in the precore/core region through phylogenetic analysis, and the relevance of viral characteristics in disease progression in Korean patients. 133 patients with chronic HBV infection were enrolled. The precore and core region of HBV was amplified and sequenced. Phylogenetic analysis was performed for subgenotyping and the changes of nucleotides and amino acid were compared in liver disease stages. HBV/C2 subgenotype was predominant in chronic HBV carriers (98.5%), followed by HBV/A2 (0.75%) and HBV/C7 (0.75%). The mutations of the precore region were not different between liver disease stages. However, amino acid changes in the cytotoxic T lymphocyte epitope (p < 0.020), CD4+ T cell epitope (p < 0.027), or B cell epitope (p < 0.029) were significantly higher in liver cirrhosis patients than in chronic hepatitis patients, but not in hepatocellular carcinoma patients. HBV/C2 is the most prevalent subgenotype in Korea, and HBV/C7 subgenotype found in the Philippines was first identified in the Korean population. Mutations in immune epitopes within the core gene were significantly associated with disease progression.
    Intervirology 02/2011; 54(6):333-8. · 2.34 Impact Factor
  • Article: Differential pattern of semantic memory organization between bipolar I and II disorders.
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    ABSTRACT: Semantic cognition is one of the key factors in psychosocial functioning. The aim of this study was to explore the differences in pattern of semantic memory organization between euthymic patients with bipolar I and II disorders using the category fluency task. Study participants included 23 euthymic subjects with bipolar I disorder, 23 matched euthymic subjects with bipolar II disorder and 23 matched control subjects. All participants were assessed for verbal learning, recall, learning strategies, and fluency. The combined methods of hierarchical clustering and multidimensional scaling were used to compare the pattern of semantic memory organization among the three groups. Quantitative measures of verbal learning, recall, learning strategies, and fluency did not differ between the three groups. A two-cluster structure of semantic memory organization was identified for the three groups. Semantic structure was more disorganized in the bipolar I disorder group compared to the bipolar II disorder. In addition, patients with bipolar II disorder used less elaborate strategies of semantic memory organization than those of controls. Compared to healthy controls, strategies for categorization in semantic memory appear to be less knowledge-based in patients with bipolar disorders. A differential pattern of semantic memory organization between bipolar I and II disorders indicates a higher risk of cognitive abnormalities in patients with bipolar I disorder compared to patients with bipolar II disorder. Exploring qualitative nature of neuropsychological domains may provide an explanatory insight into the characteristic behaviors of patients with bipolar disorders.
    Progress in Neuro-Psychopharmacology and Biological Psychiatry 02/2011; 35(4):1053-8. · 3.25 Impact Factor
  • Article: Influence of the interaction between the serotonin 1A receptor C-1019G polymorphism and negative life stressors on the development of depression.
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    ABSTRACT: The current study aimed to investigate the interaction between the serotonin 1A receptor gene (HTR1A) C-1019G polymorphism and recent negative life stressors on depression in a Korean community sample. The HTR1A C-1019G polymorphism was genotyped in 416 community-dwelling Koreans (156 males, 260 females; 44.37 ± 14.67 years old). Lifetime and current major depressive episodes were diagnosed using the Structured Clinical Interview for DSM-IV. The Center for Epidemiological Studies for Depression Scale (CES-D) was self-applied and face-to-face interviews investigating negative life stressors within the last 6 months were also performed. The results indicated that there were significant interactions between the C-1019G polymorphism and negative life stressors on CES-D scores (p = 0.02) as well as on current major depressive episodes (p = 0.002), but not on past major depressive episodes. G carriers alone had higher CES-D scores and more frequently experienced major depressive episodes after stressors. The interaction between the C-1019G polymorphism in HTR1A and recent negative life stressors accounted for current major depressive episodes and depressive symptoms. Our findings suggest that people with this gene variant may be more susceptible to developing depression especially after negative life stressors.
    Neuropsychobiology 01/2011; 64(1):1-8. · 2.67 Impact Factor
  • Article: Rosiglitazone reduces tau phosphorylation via JNK inhibition in the hippocampus of rats with type 2 diabetes and tau transfected SH-SY5Y cells.
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    ABSTRACT: Increasing evidence supports an association between Alzheimer's disease (AD) and diabetes. Rosiglitazone, a peroxisome proliferator-activated receptor-γ (PPARγ) agonist, which is an anti-diabetic agent against type 2 diabetes, is currently in Phase III clinical trials in AD patients because rosiglitazone reduces β-amyloid (Aβ) pathology and inflammation. However, few studies have investigated whether rosiglitazone affects tau phosphorylation, another critical pathological feature of AD. Thus, we investigated it using OLETF type 2 diabetic rats and streptozotocin-injected type 1 diabetic mice. Interestingly, rosiglitazone reduced tau phosphorylation only in the hippocampus of OLETF type 2 diabetes rats, and not in that of STZ-injected type 1 diabetes mice. The activity of JNK was reduced in the hippocampus of rosiglitazone-treated OLETF rats, correlating with a reduction in tau phosphorylation, however, which was not correlated with GSK3β activity. In human tau-transfected SH-SY5Y neuronal cell line, reduction of tau phosphorylation was also associated with reduction of JNK activity, not of GSK3β activity. Hence, rosiglitazone could be used in reducing tau phosphorylation through JNK inactivation for therapeutic effects in type 2 diabetes related Alzheimer's disease.
    Neurobiology of Disease 11/2010; 40(2):449-55. · 5.40 Impact Factor
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    Article: PER2 variation is associated with diurnal preference in a Korean young population.
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    ABSTRACT: The PER2 gene has been reported to influence diurnal preference. In this study, we have attempted to characterize the associations between the PER2 gene polymorphisms and diurnal preference in a population of healthy young subjects, controlling for the social and environmental confounding factors. Subjects were 299 students in a college, carefully selected to be mentally and physically healthy. All subjects completed the 13-item composite scale for morningness (CSM). PER2 gene polymorphisms were genotyped by PCR-based methods. Genotype and allele carrier status of a PER2 G3853A polymorphism (rs934945) were associated with CSM scores. Carriers of the 3853G allele showed significantly higher CSM scores (P = 0.004, P = 0.009, and P = 0.001; total, morningness, and activity plan, respectively). There were no significant differences on CSM scores among genotypes and allele status of PER2 rs2304672. This result indicates that rs934945 of PER2 may be associated with diurnal preference in a Korean healthy population.
    Behavior Genetics 10/2010; 41(2):273-7. · 2.52 Impact Factor
  • Article: Association study between antipsychotic-induced restless legs syndrome and polymorphisms of monoamine oxidase genes in schizophrenia.
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    ABSTRACT: This study aimed to investigate whether the monoamine oxidase (MAO) A and B genes are associated with antipsychotic-induced restless legs syndrome (RLS) in schizophrenia. We assessed antipsychotic-induced RLS symptoms in 190 Korean schizophrenic patients and divided the subjects into two groups: those with RLS symptoms (n = 96) and those without RLS symptoms (n = 94). Genotyping was performed for the variable number of tandem repeat (VNTR) polymorphism of the MAOA gene and A644G polymorphism of the MAOB gene. There was no significant difference in the genotype and allele frequencies of all polymorphisms investigated between these two groups. However, the result of global haplotype analysis showed a significant difference in haplotype frequencies between male subjects with and without RLS symptoms (p = 0.013). The interaction between two polymorphisms had a significant effect on the RLS scores of both male (p = 0.047) and female (p = 0.028) patients. These data do not suggest that the MAOA gene VNTR and MAOB gene A644G polymorphisms are associated with antipsychotic-induced RLS symptoms in schizophrenia. However, we found that the haplotype frequencies differed between the male schizophrenic patients with and without RLS symptom and the interaction between the two polymorphisms had a significant influence on the RLS scores of patients with schizophrenia.
    Human Psychopharmacology Clinical and Experimental 07/2010; 25(5):397-403. · 2.48 Impact Factor
  • Article: Bioimaging for targeted delivery of hyaluronic Acid derivatives to the livers in cirrhotic mice using quantum dots.
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    ABSTRACT: Liver fibrosis or cirrhosis is one of the representative liver diseases with a high morbidity and mortality worldwide. Over the past decades, many kinds of antifibrotic compounds have been investigated in vitro and in vivo for the treatment of liver cirrhosis. In this work, real-time bioimaging of hyaluronic acid (HA) derivatives was carried out using quantum dots (QDots) to assess the possibility of HA derivatives as target-specific drug delivery carriers for the treatment of liver diseases. HA-QDot conjugates with an HA modification degree of about 22 mol % was synthesized by amide bond formation between carboxyl groups of QDots and amine groups of adipic acid dihydrazide modified HA (HA-ADH). According to in vitro cell culture tests, HA-QDot conjugates were taken up more to the cells causing chronic liver diseases such as hepatic stellate cells (HSC-T6) and hepatoma cells (HepG2) than normal hepatocytes (FL83B). After tail-vein injection, HA-QDot conjugates were target-specific, being delivered to the cirrhotic liver with a slow clearance longer than 8 days. Furthermore, immunofluorescence and flow cytometric analyses of dissected liver tissues revealed the target-specific delivery of HA derivatives to liver sinusoidal endothelial cells (LSEC) and HSC. The results were thought to reflect the feasibility of HA derivatives as novel drug delivery carriers for the treatment of various chronic liver diseases including hepatitis, liver cirrhosis, and liver cancer.
    ACS Nano 06/2010; 4(6):3005-14. · 10.77 Impact Factor
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    Article: Lack of Association between Glutathione S-Transferase-M1, -T1, and -P1 Polymorphisms and Olanzapine-Induced Weight Gain in Korean Schizophrenic Patients.
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    ABSTRACT: Oxidative stress may be an important pathogenic mechanism in the obesity and metabolic syndrome. The aims of this study was to assess the possible association between the oxidative stress related Glutathione S-Transferase genes (GST-M1, GST-T1, and GST-P1) variants and the olanzapine-induced weight gain in Korean schizophrenic patients. We categorized 78 schizophrenic patients into two groups the more than 7% weight gain from baseline (weight gain >/=7%) and the less weight gain (weight gain <7%) groups according to weight change between before and after long-term olanzapine treatment (440+/-288 days). All participants were genotyped for the GST-M1, GST-T1 and GST-P1 genes. Differences in allele frequencies between cohorts with different body weight changes were evaluated by a chi-square analysis and Fisher's exact test. The multifactor dimensionality reduction (MDR) approach was used to analyze gene-gene interactions. Mean body weight gain was 5.42 kg. There was no difference in the null genotype distribution of GST-M1 and -T1 between subjects with body weight gain >/=7% compared to subjects with body weight gain <7% (p>0.05). No significant difference in GST-P1 genotype and allele frequencies were observed between the groups (p>0.05). MDR analysis did not show a significant interaction between the three GST gene variants and susceptibility to weight gain (p>0.05). These findings do not support a relationship between the genetic variants of three GST genes (GST-M1, -T1 and -P1) and weight gain in Korean schizophrenic patients receiving olanzapine treatment.
    Psychiatry investigation 06/2010; 7(2):147-52. · 0.99 Impact Factor

Institutions

  • 2012
    • Korea University
      • Department of Psychiatry
      Seoul, Seoul, South Korea
  • 2008–2012
    • Catholic University of Korea
      • College of Medicine
      Seoul, Seoul, South Korea
    • Kangbuk Samsung Hospital
      Seoul, Seoul, South Korea
  • 2009–2011
    • Yonsei University Hospital
      Seoul, Seoul, South Korea
    • Inje University Paik Hospital
      Goyang, Gyeonggi, South Korea
    • Seoul National University Bundang Hospital
      • Department of Psychiatry
      Seoul, Seoul, South Korea
    • Gachon University
      • Department of Psychiatry
      Seoul, Seoul, South Korea
  • 2004–2010
    • Ulsan University Hospital
      Ulsan, Ulsan, South Korea