• Journal of Dental Rehabilitation and Applied Science
• /
• v.36 no.3
• /
• pp.145-157
• /
• 2020

Purpose: This study was to determine the possible effects of trichloroacetic acid (TCA) and epidermal growth factor (EGF) through cell survival genes of the PI3K-AKT signaling pathway when applying an hydrophobically modified glycol chitosan (HGC)-based nanocontrolled release system to human gingival fibroblasts in oral soft tissue regeneration. Materials and Methods: An HGC-based nano-controlled release system was produced, followed by the loading of TCA and EGF. The group was divided into control (CON), TCA-loaded nano-controlled release system (EXP1), and the TCA- and EGF- individually loaded nano-controlled release system (EXP2). A total for 29 genes related to the PI3K-AKT signaling pathway were analyzed after 48h of culture in human gingival fibroblasts. Real-time PCR, 1- way ANOVA and multiple regression analysis were performed. Results: Cell survival genes were significantly upregulated in EXP1 and EXP2. From multiple regression analysis, ITGB1 was determined to be the most influential factor for AKT1 expression. Conclusion: The application of TCA and EGF through the HGC-based nano-controlled release system can up-regulate the cell survival pathway.

• Korean Journal of Microbiology
• /
• v.54 no.3
• /
• pp.237-243
• /
• 2018

The pathogenic free-living amoebas (FLAs), Acanthamoeba spp. and Naegleria fowleri, can cause fatal infections, including amoebic encephalitis. They are ubiquitously distributed in nature, including in diverse bodies of water. In order to survey Acanthamoeba spp. and N. fowleri in source water in Korea, we used culture-based real-time PCR to detect viable FLAs in 52 source water samples collected between July 2017 and December 2017. Acanthamoeba spp. and N. fowleri were detected in 42 samples (80.8%) and 6 samples (11.5%), respectively. Acanthamoeba spp. were detected at approximately the same frequency in all seasons, but N. fowleri was mainly detected in summer and autumn, with no N. fowleri detected in winter. These results demonstrate that these pathogenic FLAs, especially N. fowleri, which has caused deaths in the United States and China, are widely distributed in the Korean aquatic environment.

• Korean Journal of Clinical Laboratory Science
• /
• v.53 no.1
• /
• pp.49-59
• /
• 2021

This study investigated the use of real-time PCR melting curves for the diagnosis of blaKPC and blaNDM genes among the most frequently detected carbapenemase-producing Enterobacteriaceae in Korea. As a means of addressing the shortcomings of phenotype tests and conventional PCR. The modified Hodge test confirmed positivity in 25 of 35 strains, and carbapenemase inhibition testing confirmed positivity in 14 strains by meropenem+PBA or meropenem+EDTA. PCR analysis showed amplification products in 25 strains of Klebsiella pneumoniae carbapenemases (KPC), 10 of K. pneumoniae, 5 of E. coli, 5 of A. baumannii, 4 of P. aeruginosa, and 1 of P. putida. New Delhi metallo β-lactamase (NDM) identified amplification products in 8 strains, that is, 2 K. pneumoniae, 3 E. coli, 1 P. aeruginosa, 1 E. cloacae, and 1 P. retgeri strains. Real-time PCR melting curve analysis confirmed amplification in 25 strains of KPC and 8 strains of NDM, and these results were 100% consistent with PCR results. In conclusion, our findings suggest early diagnosis of carbapenem resistant Enterobacteriaceae by real-time PCR offers a potential means of antibacterial management that can prevent and control nosocomial infection spread.

• Journal of the Korean Applied Science and Technology
• /
• v.40 no.5
• /
• pp.965-976
• /
• 2023

Reynoutria japonica is a perennate plant belonging to Polygonaceae and grows wild in East Asia containing Korea. Roots of Reynoutria japonica (R. japonica), part of roots of Reynoutria japonica, has been used for anti-inflammation and antispasmodics and contains emodin as active compound. Epidermis of skin is crucial roles to defense our body against stimulants, harmful substance and prevent water loss. In this study, we examined the effect of R. japonica and emodin, its active compound, on skin-barrier and moisturizing on HaCaT cells. First, antioxidant effect of R. japonica was prominent by scavenging ABTS⁺ radicals. Next, we conducted real time PCR and expression of filaggrin mRNA which is crucial role in differentiation of keratinocyte increased by R. japonica and emodin dose-dependently. In addition, R. japonica and emodin significantly elevated the expression of HAS-2 mRNA which play a role in hyaluronic acid synthesis on HaCaT cells. Taken together, R. japonica containing emodin, as active compound has potential as a cosmetic material for enhancing the function of skin-barrier and moisturizing in epidermis.

• Journal of Life Science
• /
• v.32 no.1
• /
• pp.11-22
• /
• 2022

N-methyl-D-aspartate (NMDA) receptors have received considerable attention regarding their involvement in glutamate-induced neuronal excitotoxicity. Resveratrol has been shown to exhibit neuroprotective effects against this kind of overactivation, but the underlying cellular mechanisms are not yet clearly understood. In this study, HT-22 neuronal cells were treated with NMDA in Mg²⁺-free buffer and subsequently used as an experimental model of glutamate excitotoxicity to elucidate the mechanisms of resveratrol-induced neuroprotection. We found that NMDA treatment causes a drop in MTT reduction ability, disrupts inside-negative transmembrane potential of mitochondria, depletes cellular ATP levels, and stimulates intracellular ROS production. Double fluorescence imaging studies demonstrated an increased formation of mitochondrial permeability transition (MPT) pores accompanied by apoptotic cell death, while cobalt protoporphyrin and bilirubin showed protective effects against NMDA-induced mitochondrial injury. On the other hand, zinc protoporphyrin IX significantly attenuated the protective effects of resveratrol which was itself shown to enhance heme oxygenase-1 (HO-1) mRNA and protein expression levels. In cells transfected with HO-1 small interfering RNA, resveratrol failed to suppress the NMDA-induced effects on MTT reduction ability and MPT pore formation. The present study suggests that resveratrol may prevent mitochondrial injury in NMDA- treated HT-22 cells and that enhanced expression of HO-1 is involved in the underlying cellular mechanism.

• Neonatal Medicine
• /
• v.18 no.1
• /
• pp.59-69
• /
• 2011

Purpose: Current studies have demonstrated the neuroprotective effects of 6-cyano-7-nitroquinoxalin-2,3-dione (CNQX) in many animal models of brain injury, including hypoxic-ischemic (HI) encephlopathy, trauma and excitotoxicity, but limited data are available for those during the neonatal periods. Here we investigated whether CNQX can protect the developing rat brain from HI injury via mediation of nitric oxide synthase. Methods: In an in vivo model, left carotid artery ligation was done in 7-day-old Sprague-Dawley (SD) rat pups. The animals were divided into six groups; normoxia (N), hypoxia (H), hypoxia with sham-operation (HS), hypoxia with operation (HO), HO treated with vehicle (HV), and HO treated with CNQX at a dose of 10 mg/kg (HC). Hypoxia was made by exposure to a 2 hr period in the hypoxic chamber (92% $N_2$, 8% $O_2$). In an in vitro model, embryonic cortical neuronal cell culture of SD rats at 18-day gestation was done. The cultured cells were divided into three groups: normoxia (N), hypoxia (H), and hypoxia treated with CNQX (HC). The N group was prepared in 5% $CO_2$ incubators and the other groups were placed in 1% $O_2$) incubators (94% $N_2$, 5% $CO_2$) for 16 hr. Results: In the in vitvo and in vivo models, the expressions of iNOS and eNOS were reduced in the hypoxia group when compared to the normoxia group, whereas they were increased in the CNQX-treated group compared to the hypoxia group. In contrast, the expression of nNOS was showed reversely. Conclusion: CNQX has neuroprotective property over perinatal HI brain injury via mediation of nitric oxide synthase.

• Tuberculosis and Respiratory Diseases
• /
• v.58 no.5
• /
• pp.490-497
• /
• 2005

Background : The paraoxonase enzyme plays a significant role in the detoxification of various organophosphorous compounds in mammals, and paraoxonase (PON) 1 is one of the endogenous free-radical scavenging systems in the human body. In this study, we investigated the interaction between cigarette smoking and the genetic polymorphism of PON1 with lung cancer in Korean males. Methods : Three hundred thirty five patients with lung cancer and an equal number of age-matched controls were enrolled in this study. Every subject was asked to complete a questionnaire concerning their smoking habits and alcohol drinking habits. A 5' exonuclease assay (TaqMan) was used to genotype the PON1 Q192R polymorphism. The effects of smoking habits and drinking habits, the PON1 Q192R polymorphism and their interactions were statistically analyzed. Results : Cigarette smoking and the Q/Q genotype of PON1 were significant risk factors for lung cancer. Individuals carrying the Q/Q genotype of PON1 were at a higher risk for lung cancer as compared with those individuals carrying the Q/R or R/R genotype (odds ratio, 2.84; 95% confidence interval, 1.69 - 4.79). When the groups were further stratified by the smoking status, the Q/Q PON1 was associated with lung cancer among the current or ex-smokers (odds ratio, 2.56; 95% confidence interval, 1.52 - 4.31). Current smokers or ex-smokers who had the Q/Q genotype showed an elevated risk for lung cancer (odds ratio: 15.50, 95% confidence interval: 6.76 - 35.54) as compared with the group of subjects who never smoked, and had the Q/R or R/R genotype. The odds ratios (95% confidence interval) of smokers with the PON1 Q/Q type compared to the nonsmokers with the PON1 Q/R or R/R type were 53.77 (6.55 - 441.14) for squamous cell carcinoma, 6.25 (1.38 - 28.32) for adenocarcinoma, and 59.94 (4.66 - 770.39) for small cell carcinoma, and these results were statistically significant. Conclusion : These results suggest that cigarette smoking and the PON1 Q/Q genotype are risk factors for lung cancer. The combination of cigarette smoking and the PON1 Q/Q genotype significantly increased the lung cancer risk irrespective of the histologic type of cancer.

• Korean Journal of Clinical Laboratory Science
• /
• v.52 no.3
• /
• pp.284-295
• /
• 2020

In December 2019, the first coronavirus disease- 2019 (COVID-19) patient was reported in Wuhan, Hubei Province, China. Since then, the number of patients who suffered severe acute respiratory syndrome caused by the novel Coronavirus (SARS-CoV-2 or 2019-nCoV) has increased dramatically in Korea. This new variant virus induces pulmonary diseases, including cough, sore throat, rhinorrhea, dyspnea, and pneumonia. Because SARS-CoV-2 is an RNA virus, real-time reverse-transcriptase PCR has been used widely to diagnose COVID-19. As the Korea Centers for Disease Prevention and Control (KCDC) and Ministry of Food & Drug Safety (MFDS) approved emergency use authorization, clinical specimens collected from COVID-19 patients and even healthy people have been clinically diagnosed by laboratory medicine. Based on a literature search, this paper reviews the epidemiology, symptoms, molecular diagnostics approved by KCDC, a current diagnosis of COVID-19 in the laboratories, the difference between molecular and serological diagnosis, and guidelines for clinical specimens. In addition, the Korean guidelines of biosafety for clinical laboratory scientists are evaluated to prevent healthcare-associated infection. The author's experience and lessons as clinical laboratory scientists will provide valuable insights to protect the domestic and international health community in this COVID-19 pandemic around the world.

• Korean Journal of Clinical Laboratory Science
• /
• v.50 no.4
• /
• pp.449-456
• /
• 2018

Cervical cancer is the fourth most frequently diagnosed cancer in women worldwide. In lower Human Development Index countries, it has the second highest incidence and mortality among cancer in women. Therefore, better diagnosis and treatment systems are needed. Among them, estrogen receptor alpha ($ER-{\alpha}$) mRNA expression has been analyzed with RT-qPCR since several studies reported that $ER-{\alpha}$ is necessary in the maturation of the uterus and is related to cervical cancer. In this study, $ER-{\alpha}$ quantitative analysis was performed on various lesions and normal tissue samples. Based on the receiver operating characteristic (ROC) curve, its sensitivity and specificity were 85% and 75%, respectively, showing higher or similar results to those of conventional HPV tests. In addition, its expression level was analyzed with clinical information. With regression analysis, the R square value between the $ER-{\alpha}$ mRNA expression level and menopause status was 0.5041, indicating a strong correlation. This study was performed as part of a pilot study and suggests that $ER-{\alpha}$ is related to carcinogenesis. Future studies will examine other hormones and menopausal factors with a larger sample size.

• Clinical and Experimental Reproductive Medicine
• /
• v.34 no.3
• /
• pp.149-157
• /
• 2007

Objective: This study was performed to compare the expression of osteopontin (OPN) mRNA and protein in the eutopic and ectopic endometrial tissues in women with endometriosis and endometrial tissues in women without endometriosis. Methods: A total of 32 women with histologically confirmed endometriosis were recruited for study group. For controls, 34 women undergoing operative treatment for cervical intraepithelial neoplasia (CIN) or benign gynecologic condition other than endometriosis were recruited. At the time of laparoscopy or laparotomy, a biopsy specimen was taken from the endometrial cavity and peritoneal endometrial implant or endometrioma whenever appropriate. We employed real time quantitative RT-PCR to quantify OPN mRNA expression of these tissues and performed western blot analysis to measure the quantity of OPN. Results: The expression of OPN mRNA was significantly higher in both eutopic and ectopic endometrial tissues of women with endometriosis than in endometrial tissues of controls during both proliferative and secretory phase. In the eutopic endometrial tissue of women with endometriosis, OPN mRNA expression significantly increased during the secretory phase compared to the proliferative phase in women with endometriosis as well as controls. However, in the ectopic endometrial tissue, OPN mRNA expression significantly decreased during the secretory phase compared to the proliferative phase. The expression of OPN protein was significantly higher in women with endometriosis than in controls. Conclusion: This study shows the marked expression of OPN mRNA and protein in eutopic and ectopic endometrial tissues in women with endometriosis may be associated with the adhesion and invasion of endometrial explants.