• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.75-84
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• 2014

Aberrant DNA methylation of tumor suppressor genes has been reported in all major types of leukemia with potential involvement in the inactivation of regulatory cell cycle and apoptosis genes. However, most of the previous reports did not show the extent of concurrent methylation of multiple genes in the four leukemia types. Here, we analyzed six key genes (p14, p15, p16, p53, DAPK and TMS1) for DNA methylation using methylation specific PCR to analyze peripheral blood of 78 leukemia patients (24 CML, 25 CLL, 12 AML, and 17 ALL) and 24 healthy volunteers. In CML, methylation was detected for p15 (11%), p16 (9%), p53 (23%) and DAPK (23%), in CLL, p14 (25%), p15 (19%), p16 (12%), p53 (17%) and DAPK (36%), in AML, p14 (8%), p15 (45%), p53 (9%) and DAPK (17%) and in ALL, p15 (14%), p16 (8%), and p53 (8%). This study highlighted an essential role of DAPK methylation in chronic leukemia in contrast to p15 methylation in the acute cases, whereas TMS1 hypermethylation was absent in all cases. Furthermore, hypermethylation of multiple genes per patient was observed, with obvious selectiveness in the 9p21 chromosomal region genes (p14, p15 and p16). Interestingly, methylation of p15 increased the risk of methylation in p53, and vice versa, by five folds (p=0.03) indicating possible synergistic epigenetic disruption of different phases of the cell cycle or between the cell cycle and apoptosis. The investigation of multiple relationships between methylated genes might shed light on tumor specific inactivation of the cell cycle and apoptotic pathways.

• Korean Journal of Psychosomatic Medicine
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• v.20 no.2
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• pp.105-111
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• 2012

Objectives : We investigated the prevalence and composite score of the neuropsychiatric symptoms in patients with mild cognitive impairment(MCI), and dementia of Alzheimer's type(AD). The aim of this study is to analyze the correlation between the result of Korean Neuropsychiatric Inventory(K-NPI) and cognitive function. Methods : A total of 163 patients diagnosed with MCI or AD was divided into three groups(55 MCI patients, 56 dementia patients with mild stage, and 52 dementia patients with moderate, severe stage). We examined neuro-psychiatric symptoms by K-NPI and compared the prevalence and composite score of each subdomain in K-NPI among three groups. Results : The most common symptoms in the MCI group were depression/dysphoria, sleep/night-time behavior, anxiety, and irritability/lability. In mild AD group, the most frequent disturbance was agitation/aggression, depression/dysphoria, anxiety, apathy/indifference, and sleep/night-time behavior. In moderate to severe AD group, the most frequent disturbance was apathy/indifference, depression/dysphoria, agitation/aggression, and delusion. The frequencies of delusion, hallucination, agitation/aggression, apathy/indifference, aberrant motor behavior, appetite/eating change were statistically significant. The total NPI score showed a negative correlation with MMSE-KC and a positive correlation with GDS. Conclusions : Neuropsychiatric symptoms are common features of MCI and AD. These symptoms observed in MCI are similar to those of mild AD. Psychosis is most common in moderate to severe AD, leading to a faster rate of cognitive decline. Therefore, proper management according to the neuropsychiatric symptoms of MCI and three stages of dementia is needed.

• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.343-349
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• 1994

A number of neurological syndromes(e.g. tardive dyskinesia) are developed as a consequence of chronic treatment with neuroleptics or antipsychotic agents. Despite the long and succesful use of phenothiazine derivatives and related agents in the treatment of certain states of mental disease, the mechanisms of these drugs are still poorly understood. One current hypothesis from extensive reviews is that these compounds might significantly interfere with the cyclic nucleotide system in brain (Levin and Weiss, 1977; Nowicki et al., 1991; Haley et al., 1992). Nitric oxide (NO), one of an interesting messenger molecule and aberrant transmitter, is believed to play a important role in biological functions of cyclic nucleotides in nervous system. It has been reported that calcium-dependent NO synthesis in endothelial cytosol is mediated by calmodulin which is supposed to be tightly related to pharmacological actions of antipsychotic agents. In the present study, the effect of several antipsychotic agents on the activity of NO synthesis and formation of cyclic GMP were investigated. These agents inhibited both the formation of $[^3H]L-citrulline$ and that of $[^3H]cyclic$ GMP by concentration-dependent manner, and their inhibiting patterns are so similar to that of calmodulin antagonist.

• Journal of Veterinary Clinics
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• v.26 no.1
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• pp.23-28
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• 2009

Peritoneal dialysis (PD) is a clinical technique that therapeutically removes toxic solutes from body fluids and normalizes endogenous solutes whose aberrant concentrations disrupt normal physiology. This study retrospectively evaluated clinical outcomes and complications of PD in 20 dogs with renal failure. Blood works (total count of red blood cells (RBC), packed cell volume (PCV), the serum biochemical, and electrolyte values related to renal insufficiency) and complications associated with peritoneal dialysis, and clinical outcomes were recorded before and after PD. Additionally, creatinine reduction ratio (CRR) and urea nitrogen reduction ratio (URR) were calculated for evaluating the efficacy of PD. PD resulted in a significant (p < 0.05) reduction in blood urea nitrogen (BUN) concentration in 19 dogs, while a significant (p < 0.05) reduction in creatinine concentration in 17 dogs. The complications of PD were hypoalbuminemia (12/20, 60%), anemia (10/20, 50%), subcutaneous dialysate leakage (9/20, 45%), bacterial peritonitis (6/20, 30%), dialysate retention (5/20, 25%) and limb edema (4/20, 20%). This study demonstrated that PD was effective in reducing the magnitude of azotemia in dogs with renal failure especially in acute phase, although the complication rate was high but manageable.

• Journal of Gastric Cancer
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• v.3 no.1
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• pp.50-55
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• 2003

Background: An aberrant function of the mismatch repair system has been reported to underlie carcinogenesis in several tumors, including colorectal and gastric carcinomas, and to induce the typical genotype of microsatellite instability (MSI). Purpose: We aimed to determine the frequency of MSI in early-onset sporadic gastric carcinoma and elucidate the role of promoter methylation in hMLH1 as the mechanism of MSI. Materials and Methods: Thirty-six early-onset sporadic gastric carcinomas were analyzed to determine the status of MSI and the frequency of methylation of the promoter region in hMLH1. MSI was determined using five markers recommended by NCI: MSI-H (high), MSI-L (low), and MSS (Microsatellite stable). Methylation specific PCR (MSP) and direct automated genomic sequencing analysis with DNA modified by sodium bisulfite have been performed to confirm promoter region methylation. All the data were analyzed regarding characteristics of molecular changes, and clinicopathologic variables. Results: The microsatellite status was determined as MSI-H in five cases ($13.8\%$), MSI-L in 13 cases ($36.1\%$), and MSS in 18 cases ($50.0\%$). hMLH1 was methylated in seven cases ($19.4\%$). In all cases of MSI-H, promoter of hMLH1 was methylated, and in two of the 13 cases of MSI-L, hMLH1 promoter methylation was identified. Methylation was not found in any cases of MSS. Promoter methylation in hMLH1 was significantly correlated with MSI status (P<0.001). We could not find any relationship between MSI and clinicopathologic parameters. Conclusion: These results suggest that an abnormal function of the mismatch repair system may be associated with gastric carcinogenesis in more than $10\%$ of early-onset gastric carcinomas and MSI appeared to be closely related to the promoter methylation in hMLH1.

• Environmental Mutagens and Carcinogens
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• v.22 no.2
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• pp.112-124
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• 2002

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to exert detrimental toxicities on various organ systems including reproductive, cardiovascular, nervous, or dermal system. Immunomodulatory effects of TCDD is thymic atrophy, downregulation of cytotoxic T or B lymphocyte differentiation and activation, which were demonstrated using experimental animals, whereas immunotoxicity in human has not been investigated well. This study was proceeded to evaluate general immunologic spectrum of the Korean Vietnam War veterans exposed to TCDD during their operation, and compare with that of the non-exposed control subjects with similar age. Regarding composition and quantity, immune cells in peripheral blood collected from the TCDD-exposed was not much different from those of the control except decreased red blood cell, hemoglobin and hematocrit level. Furthermore, plasma IgG2, G3, and G4 isotype distribution was similar between two groups, but IgG1 level was significantly lowered in the TCDD-exposed, indicating a TCDD-mediated functional alteration of B cells. Significantly enhanced level of IgE in plasma, a hallmark of dermal or respiratory allergic response, was also observed in the TCDD-exposed compared with that of the control. Elevated generation of IL-4 and IL-10 was resulted from in vitro stimulation of T cells with PMA plus ionomycin or PHA, respectively, from the TCDD-exposed in comparison to those of the control, suggesting a skewed type-2 response. In addition, the level of IFN${\gamma}$, a multifunctional cytokine for T cell-mediated immunity, was lowered in the TCDD-exposed with upregulation of tumor necrosis factor $\alpha$. The present study suggests that TCDD exposure disturbs immunohomeostasis in humans observed as an aberrant plasma IgE and IgG1 levels and dysregulation of T cell activities.

• Toxicological Research
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• v.26 no.4
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• pp.261-266
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• 2010

In the workplace, the arsenic is used in the semiconductor production and the manufacturing of pigments, glass, pesticides and fungicides. Therefore, workers may be exposed to airborne arsenic during its use in manufacturing. The purpose of this study was to evaluate the potential toxicity of particulate matters (PMs) doped with arsenic (PMs-Arsenic) using a rodent model and to compare the genotoxicity in various concentrations and to examine the role of PMs-Arsenic in the induction of signaling pathway in the lung. Mice were exposed to PMs $124.4{\pm}24.5\;{\mu}g/m^3$ (low concentration), $220.2{\pm}34.5\;{\mu}g/m^3$ (middle concentration), $426.4{\pm}40.3\;{\mu}g/m^3$ (high concentration) doped with arsenic $1.4\;{\mu}g/m^3$ (Low concentration), $2.5\;{\mu}g/m^3$ (middle concentration), $5.7\;{\mu}g/m^3$ (high concentration) for 4 wks (6 h/d, 5 d/wk), respectively in the whole-body inhalation exposure chambers. To determine the level of genotoxicity, Chromosomal aberration (CA) assay in splenic lymphocytes and Supravital micronucleus (SMN) assay were performed. Then, signal pathway in the lung was analyzed. In the genotoxicity experiments, the increases of aberrant cells were concentration-dependent. Also, PMs-arsenic caused peripheral blood micronucleus frequency at high concentration. The inhalation of PMs-Arsenic increased an expression of phosphorylated Akt (p-Akt: protein kinase B) and phpsphorylated mammalian target of rapamycin (p-mTOR) at high concentration group. Taken together, inhaled PMs-Arsenic caused genotoxicity and altered Akt signaling pathway in the lung. Therefore, the inhalation of PMs-Arsenic needs for a careful risk assessment in the workplace.

• Molecules and Cells
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• v.41 no.3
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• pp.224-233
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• 2018

Primary cilia are solitary, non-motile, axonemal microtubule-based antenna-like organelles that project from the plasma membrane of most mammalian cells and are implicated in transducing hedgehog signals during development. It was recently proposed that aberrant SHH signaling may be implicated in the progression of idiopathic pulmonary fibrosis (IPF). However, the distribution and role of primary cilia in IPF remains unclear. Here, we clearly observed the primary cilia in alveolar epithelial cells, fibroblasts, and endothelial cells of human normal lung tissue. Then, we investigated the distribution of primary cilia in human IPF tissue samples using immunofluorescence. Tissues from six IPF cases showed an increase in the number of primary cilia in alveolar cells and fibroblasts. In addition, we observed an increase in ciliogenesis related genes such as IFT20 and IFT88 in IPF. Since major components of the SHH signaling pathway are known to be localized in primary cilia, we quantified the mRNA expression of the SHH signaling components using qRT-PCR in both IPF and control lung. mRNA levels of SHH, the coreceptor SMO, and the transcription factors GLI1 and GLI2 were upregulated in IPF compared with control. Furthermore, the nuclear localization of GLI1 was observed mainly in alveolar epithelia and fibroblasts. In addition, we showed that defective KIF3A-mediated ciliary loss in human type II alveolar epithelial cell lines leads to disruption of SHH signaling. These results indicate that a significant increase in the number of primary cilia in IPF contributes to the upregulation of SHH signals.

• Molecules and Cells
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• v.43 no.4
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• pp.408-418
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• 2020

The sinus node (SN) is located at the apex of the cardiac conduction system, and SN dysfunction (SND)-characterized by electrical remodeling-is generally attributed to idiopathic fibrosis or ischemic injuries in the SN. SND is associated with increased risk of cardiovascular disorders, including syncope, heart failure, and atrial arrhythmias, particularly atrial fibrillation. One of the histological SND hallmarks is degenerative atrial remodeling that is associated with conduction abnormalities and increased right atrial refractoriness. Although SND is frequently accompanied by increased fibrosis in the right atrium (RA), its molecular basis still remains elusive. Therefore, we investigated whether SND can induce significant molecular changes that account for the structural remodeling of RA. Towards this, we employed a rabbit model of experimental SND, and then compared the genome-wide RNA expression profiles in RA between SND-induced rabbits and sham-operated controls to identify the differentially expressed transcripts. The accompanying gene enrichment analysis revealed extensive pro-fibrotic changes within 7 days after the SN ablation, including activation of transforming growth factor-β (TGF-β) signaling and alterations in the levels of extracellular matrix components and their regulators. Importantly, our findings suggest that periostin, a matricellular factor that regulates the development of cardiac tissue, might play a key role in mediating TGF-β-signaling-induced aberrant atrial remodeling. In conclusion, the present study provides valuable information regarding the molecular signatures underlying SND-induced atrial remodeling, and indicates that periostin can be potentially used in the diagnosis of fibroproliferative cardiac dysfunctions.

• Journal of Genetic Medicine
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• v.6 no.1
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• pp.1-7
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• 2009

Epigenetic changes represented by promoter CpG island hypermethylation and histone modification are an important carcinogenetic mechanism, which is found in virtually all histologic types of human cancer. About 60-70% of human genes harbor CpG islands in their promoters and 5' exonal sequences, and some of them undergo aberrant promoter CpG island hypermethylation and subsequent downregulation of gene expression. The loss of expression in tumor suppressor or tumor-related genes results in acceleration of tumorigenic processes. In addition to regional CpG island hypermethylation, diffuse genomic hypomethylation represents an important aspect of DNA methylation changes occurring in human cancer cells and contributes to chromosomal instability. These apparently contrasting methylation changes occur not only in human cancer cells, but also in premalignant cells. CpG island hypermethylation has gained attention for not only the tumorigenic mechanistic process, but also its potential utilization as a tumor biomarker. DNA methylation markers are actively investigated for their potential uses as tumor biomarkers for diagnosis of tumors in body fluids, prognostication of cancer patients, or prediction of chemotherapeutic drug response. In this review, these aspects will be discussed in detail.