The identification of the DNA structure as a doublestranded helix consisting of two nucleotide chain molecules was a milestone in modern molecular biology. The DNA chip technology is based on reverse hybridization that follows the principle of complementary binding of doublestranded DNA. DNA chip can be described as the deposition of defined nucleic acid sequences, probes, on a solid substrate to form a regular array of elements that are available for hybridization to complementary nucleic acids, targets. DNA chips based on cDNA clones, oligonucleotides and genomic clones have been developed for gene expression studies, genetic variation analysis and genomic changes associated with diseases including cancers and genetic diseases. DNA chips for gene expression profiling can be used for functional analysis in human cells and animal models, diseaserelated gene studies, assessment of gene therapy, assessment of genetically modified food, and research for drug discovery. DNA chips for genetic variation detection can beused for the detection of mutations or chromosomal abnormalities in cancers, drug resistances in cancer cells or pathogenic microbes, histocompatibility analysis for transplantation, individual identification for forensic medicine, and detection and discrimination of pathogenic microbes. The DNA chip will be generalized as a useful tool in clinical diagnostics in the near future. Labona chip and informatics will facilitate the development of a variety of DNA chips for diagnostic purposes.
Chromosome Aberrations ; Clone Cells ; Discrimination (Psychology) ; DNA* ; DNA, Complementary ; Drug Discovery ; Food, Genetically Modified ; Forensic Medicine ; Gene Expression ; Gene Expression Profiling ; Genetic Therapy ; Genetic Variation ; Histocompatibility ; Humans ; Informatics ; Models, Animal ; Molecular Biology ; Nucleic Acids ; Oligonucleotide Array Sequence Analysis* ; Oligonucleotides

Skin exposure to low-dose ultraviolet B (UVB) light up-regulates the expression of matrix metalloproteinase-1 (MMP-1), thus contributing to premature skin aging (photo-aging). Although cyclooxygenase-2 (COX-2) and its product, prostaglandin E2 (PGE2), have been associated with UVB-induced signaling to MMP expression, very little are known about the roles of lipoxygenases and their products, especially leukotriene B4 (LTB4) and 12(S)-hydroxyeicosatetraenoic acid (12(S)-HETE), in MMP-1 expression in skin keratinocytes. In the present study, we demonstrate that BLT2, a cell surface receptor for LTB4 and 12(S)-HETE, plays a critical role in UVB-mediated MMP-1 upregulation in human HaCaT keratinocytes. Moreover, our results demonstrated that BLT2-mediated MMP-1 upregulation occurs through a signaling pathway dependent on reactive oxygen species (ROS) production and the subsequent stimulation of ERK. Blockage of BLT2 via siRNA knockdown or with the BLT2-antagonist LY255283 completely abolished the up-regulated expression of MMP-1 induced by low-dose UVB irradiation. Finally, when HaCaT cells were transiently transfected with a BLT2 expression plasmid, MMP-1 expression was significantly enhanced, along with ERK phosphorylation, suggesting that BLT2 overexpression alone is sufficient for MMP-1 up-regulation. Together, our results suggest that the BLT2-ROS-ERK-linked cascade is a novel signaling mechanism for MMP-1 upregulation in low-dose UVB-irradiated keratinocytes and thus potentially contributes to photo-aging.
12-Hydroxy-5,8,10,14-eicosatetraenoic Acid/biosynthesis ; Cell Line ; Extracellular Signal-Regulated MAP Kinases/metabolism ; Humans ; Keratinocytes/metabolism/*radiation effects ; Leukotriene B4/biosynthesis ; Matrix Metalloproteinase 1/*biosynthesis ; Phosphorylation ; Reactive Oxygen Species/metabolism ; Receptors, Leukotriene B4/*physiology ; Signal Transduction ; Ultraviolet Rays/*adverse effects

Purpose: To assess the diagnostic value of optical coherence tomography angiography (OCTA), and the factors affecting the diagnosis of polypoidal choroidal vasculopathy (PCV) by OCTA and indocyanine green angiography (ICGA). Methods: The numbers and area of polyps, and the presence and area of a branched vascular network (BVN) as revealed by ICGA and OCTA, were retrospectively analyzed in 43 patients with active PCV. The patients were divided into two groups according to whether the number of polyps matched between the two methods: group 1, equal number of polyps revealed by ICGA and OCTA; group 2, different number of polyps revealed by ICGA and OCTA. Results: In 43 PCV patients, the total number of polyps was 1.47 ± 0.83 in ICGA and 1.07 ± 0.91 in OCTA (p < 0.001), and the polyp area was 0.27 ± 0.42 mm2 in ICGA and 0.17 ± 0.15 mm2 in OCTA (p = 0.023). BVN was found in 33 eyes (76.7%) by ICGA and 29 eyes (67.4%) by OCTA (p < 0.001). The BVN area was 3.61 ± 2.59 mm2 in ICGA and 2.74 ± 2.76 mm2 in OCTA (p = 0.002). Central retinal thickness and central choroidal thickness were significantly greater in group 2 than group 1 (p < 0.001, respectively). Subretinal fluid (SRF) (p = 0.009) and subretinal hemorrhage (SRH) (p = 0.005) were significantly more prevalent in group 2 than group 1. Polyp height (p = 0.022) and diameter (p = 0.042) were significantly greater in group 2 than group 1. Conclusions OCTA is a supplementary diagnostic technique for detecting PCV. The presence of SRF and SHR, and large polyp height and diameter, were associated with the polyp detection rate of OCTA for PCV.

Purpose: To assess the diagnostic value of optical coherence tomography angiography (OCTA), and the factors affecting the diagnosis of polypoidal choroidal vasculopathy (PCV) by OCTA and indocyanine green angiography (ICGA). Methods: The numbers and area of polyps, and the presence and area of a branched vascular network (BVN) as revealed by ICGA and OCTA, were retrospectively analyzed in 43 patients with active PCV. The patients were divided into two groups according to whether the number of polyps matched between the two methods: group 1, equal number of polyps revealed by ICGA and OCTA; group 2, different number of polyps revealed by ICGA and OCTA. Results: In 43 PCV patients, the total number of polyps was 1.47 ± 0.83 in ICGA and 1.07 ± 0.91 in OCTA (p < 0.001), and the polyp area was 0.27 ± 0.42 mm2 in ICGA and 0.17 ± 0.15 mm2 in OCTA (p = 0.023). BVN was found in 33 eyes (76.7%) by ICGA and 29 eyes (67.4%) by OCTA (p < 0.001). The BVN area was 3.61 ± 2.59 mm2 in ICGA and 2.74 ± 2.76 mm2 in OCTA (p = 0.002). Central retinal thickness and central choroidal thickness were significantly greater in group 2 than group 1 (p < 0.001, respectively). Subretinal fluid (SRF) (p = 0.009) and subretinal hemorrhage (SRH) (p = 0.005) were significantly more prevalent in group 2 than group 1. Polyp height (p = 0.022) and diameter (p = 0.042) were significantly greater in group 2 than group 1. Conclusions OCTA is a supplementary diagnostic technique for detecting PCV. The presence of SRF and SHR, and large polyp height and diameter, were associated with the polyp detection rate of OCTA for PCV.

BACKGROUND: Oligonucleotide chip technology has proven to be a very useful tool in the rapid diagnosis of infectious disease. Rifampin resistance is considered as a useful marker of multidrug-resistance in tuberculosis. Mutations in the rpoB gene coding β subunit of RNA polymerase represent the main mechanism of rifampin resistance. The purpose of this study was to develop a diagnosis kit using oligonucleotide chip for the rapid and accurate detection of rifampin-resistance in Mycobacterium tuberculosis. METHOD: Tle sequence specific probes for mutations in the rpoB gene were designed and spotted onto the glass slide, oligonucleotide chip. 38 clinical isolates of Mycobacterium were tested. A part of rpoB was amplified, labelled, and hybridized on the oligonucleotide chip with probes. Results were analyzed with a laser scanner. Direct sequencing was done to verify the results. RESULT: The low-density oligonucleotide chip designed to determine the specific mutations in the rpoB gene of M. tuberculosis accurately detected rifampin resistance associated with mutations in 28 clinical isolates. Mutations at codons 531, 526, and 513 were confirmed by direct sequencing analysis. CONCLUSION: Mutant detection using oligonucleotide chip technology is a reliable and useful diagnostic tool for the detection of multidrug-resistance in M. tuberculosis.
Clinical Coding ; Codon ; Communicable Diseases ; Diagnosis ; DNA-Directed RNA Polymerases ; Glass ; Mycobacterium ; Mycobacterium tuberculosis ; Rifampin ; Tuberculosis*

OBJECTIVES: Perceived stress scale is a self-report inventory to estimate the degree of individual perceived stress in daily life. The aim of this study was to introduce this scale and test the reliability and validity of the Korean version of PSS. METHODS: The total of 154 female hospital workers were included in this study. The survey questionnaires were conducted for demographic information. All participants were required to complete PSS, Hamilton Anxiety scale and Beck Depression Inventory. Reliability and validity studies were conducted and internal consistency was examined. RESULTS: The mean score of the PSS reported in this sample was 20.69+/-4.56. The overall Cronbach's alpha was 0.819, and the test-retest reliability coefficient was 0.66. PSS had a significant positive correlation with the HAM-A(r=0.49, p<0.01), and the BDI(r=0.55, p<0.01). Factor analysis yielded 2 factors with eigenvalues of 3.924 and 2.608, accounting for 65 percent of variance. Factor 1 represented "stress" and factor 2 represented "control of stress". CONCLUSIONS: This study indicates that the PSS is appropriate for estimating the perceived stress levels. These results support the use of PSS in large sections of the population in Korea.
Accounting ; Anxiety ; Depression ; Female ; Humans ; Korea ; Questionnaires ; Reproducibility of Results

Although the biological causes of depression have been well established, the current use of antidepressants are still mostly based on the monoamine hypothesis of depression. However, monoamine antidepressants delay treatment of depression, and there is the problem of depressed patients who are resistant. Ketamine, a N-methyl-D-aspartate receptor (NMDAR) antagonist, is firstly introduced as an anesthetic. The hypothesis on the mechanism of ketamine as an antidepressant has been proposed through direct NMDAR inhibition, inhibition of γ-aminobutyric acid-ergic interneuron NMDARs and the role of ketamine metabolite (2R,6R)-hydroxynorcetamine (HNK). The ketamine also reverses the lack of synaptic connectivity and neurotrophic factors in depressed states by downstream mechanism of action. Through preclinical trials, there is a growing body of evidence indicating that ketamine has the potential for treatment of depression. In recent clinical studies, ketamine exhibits rapid-acting antidepressants effects and improvement of depression and even suicidality. This review examines current researches on molecular and cellular mechanisms of ketamine as an antidepressant, and reviews the current status of clinical studies, problems, and clinical applicability of ketamine.
Antidepressive Agents ; Depression ; Glutamic Acid ; Humans ; Interneurons ; Ketamine* ; N-Methylaspartate ; Nerve Growth Factors

Objective: The Patient Health Questionnaire-4 (PHQ-4) has been used for screening owing to ease of use and brevity.In this study, we developed the Korean version of the PHQ-4 and tested its validity. Methods: One hundred sixteen new adult outpatients at the Department of Psychiatry of the Korea University Ansan Hospital participated in the study. We simultaneously administered other depression/anxiety scales: the Hamilton Rating Scale for Depression, the Hamilton Anxiety Scale, the Beck Depression Inventory, and the Beck Anxiety Inventory. Results: The mean PHQ-4 score was 6.52 (standard deviation = 3.45). Cronbach’s α was 0.792, and the intraclass correlation coefficient of test and 2-week interval retest was 0.827 (p ＜ 0.01). The Pearson correlation coefficients between the PHQ-4 total score and other depression/anxiety scales were all over 0.6. Confirmatory factorial analysis showed acceptable convergent validity and reliability but questionable discriminant validity for some model fit values. Conclusion The Korean version of the PHQ-4 has sufficient internal consistency, test-retest reliability, and construct validity, but its two-factor structure showed incompleteness. However, we suggest that it should be used as a brief screening measure for common psychiatric distress that warrants further detailed assessment, but not to separately assess the severity of depression and anxiety symptoms.

E-cigarettes, heat-not-burn (HNB) tobacco, and other new types of tobacco products are emerging in Korea. These products are particularly popular among smokers who are looking for less harmful means of tobacco consumption, and are highly relevant for existing tobacco control policies. E-cigarettes, which are electronic devices designed to allow the user to inhale nicotine as a vapor, are controversial in terms of their safety and effects on smoking cessation, as a variety of harmful substances have been detected in e-cigarette vapor. Due to policy differences in tobacco harm reduction, the regulations on e-cigarettes differ from country to country, and domestic regulations regulate e-cigarettes in a manner similar to conventional cigarettes. In contrast, HNB tobacco was introduced in Korea in June 2017, and is rapidly expanding in the market, as active marketing campaigns seek to communicate to consumers that HNB tobacco use involves no tar and is less harmful to health. However, the World Health Organization and several professional groups have argued that based on independent studies not supported by tobacco companies, HNB tobacco should be regulated in the same way as conventional cigarettes because there is no evidence that HNB tobacco is less harmful. Clinicians need to expand their understanding of new tobacco products so that they can provide appropriate counseling.
Counseling ; Electronic Cigarettes ; Harm Reduction ; Korea ; Marketing ; Nicotine ; Smoking Cessation ; Social Control, Formal ; Tobacco Products ; Tobacco Use ; Tobacco ; World Health Organization

Major depressive disorder (MDD) is a serious psychiatric illness that causes functional impairment in many people. While monoaminergic antidepressants have been used to effectively treat MDD, these antidepressants have limitations in that they have delayed onset of action and many patients remain treatment-resistant. Therefore, there is a need to develop antidepressants with a novel target, and researchers have directed their attention to the glutamatergic system. Ketamine, although developed as an anesthetic, has been found to produce an antidepressant effect at sub-anesthetic doses via N-Methyl-D-aspartic acid (NMDA) receptor blockade as well as NMDA receptor- independent pathways. A single infusion of ketamine produced rapid improvement in clinical symptoms to a considerable level and led to the resolution of serious depressive symptoms, including imminent suicidal ideation, in patients with MDD. A series of recent randomized controlled trials have provided a high level of evidence for the therapeutic efficacy of ketamine treatment in MDD and presented new insights on the dose, usage, and route of administration of ketamine as an antidepressant. With this knowledge, it is expected that ketamine treatment protocols for MDD will be established as a treatment option available in clinical practice. However, long-term safety must be taken into consideration as ketamine has abuse potential and it is associated with psychological side effects such as dissociative or psychotomimetic effects.