Publications by authors named "Hyun Kyung Kang"

Background: The objective of this study was to evaluate how effectively the bioelectric toothbrush can alleviate dentin hypersensitivity (DHS) by using electrostatic forces to remove biofilm from the tooth surface.

Methods: This study divided inpatients of a preventative dental clinic between March and October 2023 into the following two groups: a bioelectric toothbrush group (BET, n = 25) and a non-bioelectric toothbrush group (NBET, n = 18) as a control group. This was a randomized double-blind, placebo-controlled trial study.

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Background: Periodontal disease is a chronic disease that is increasing year by year. Korea also recognizes the seriousness of periodontal disease and has been applying preventive scaling in the National Health Insurance since 2013 to prevent it. Studies confirming the effectiveness of such insurance coverage are very scarce.

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This study aimed to verify and to validate the correlation between, and validate the assessment of, bacterial activity and the distribution of tongue coating, by analyzing quantitative light-induced fluorescence (QLF) images for the diagnosis of oral malodor. Oral malodor was measured using the Twin Breasor II, and bacterial activity and the distribution of tongue coating were investigated using QLF images. Bacterial activity and the distribution of tongue coating were quantitatively analyzed by dividing the tongue into six areas using the TB01 1.

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RAV1 (Related to ABI3/VP1) is a plant-specific B3 and AP2 domain-containing transcription factor that acts as a negative regulator of growth in many plant species. The expression of RAV1 is downregulated by brassinosteroids (BRs); large-scale transcriptome analyses have shown that the expression of RAV1 was previously targeted by BRI1-EMS-SUPPRESOR1 (BES1) and BRASSINAZOLE-RESISTANT1 (BZR1), which are critical transcription factors for the BR-signaling process. Using RAV1-overexpressing transgenic plants, we showed that RAV1 overexpression reduced the BR signaling capacity, resulting in the downregulation of BR biosynthetic genes and BES1 expression.

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Objectives: We investigated the risk of dementia in older adults with chronic periodontitis according to the severity of periodontitis.

Methods: Data on patients with chronic periodontitis were extracted from the National Health Insurance Service-Senior cohort database from 2002 to 2014. Among 52,728 subjects eligible for inclusion, 11,953 subjects had newly diagnosed mild chronic periodontitis (MCP), and 40,775 subjects had newly diagnosed severe chronic periodontitis (SCP).

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The aim of this study was to examine the trend of average frequency of toothbrushing per day according to the sociodemographic characteristics using the 5th, 6th, and 7th Korean National Health and Nutrition Examination Survey (KNHANES) data for 9 years; from 2010 to 2018. It intends to understand the state of toothbrushing practices in South Korea, and to provide basic data for promoting toothbrushing practices. Data from the 5th, 6th, and 7th KNHANESs conducted by the Korean Disease Control and Prevention Agency each year was analyzed using IBM SPSS version 26.

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We aimed to investigate the effects of sleep duration on impaired fasting glucose and diabetes in Korean adults with periodontal disease. This cross-sectional study was performed using data for 10,465 subjects aged >19 years who completed the periodontal examination and questionnaires in the Sixth Korea National Health and Nutrition Examination Survey (2013-2015). The effect of sleep was confirmed by a complex-sample multinomial logistic regression analysis.

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People with masticatory discomfort are unable to consume a balanced diet, which impacts their general health. We studied the relationship between quality of life and dental care associated with masticatory discomfort. Data from Korea's representative 6th Korea National Health and Nutrition Examination Survey (KNHANES) were used.

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Fisetin (3,3-,4-,7-tetrahydroxyflavone), a naturally occurring flavonoid, has antioxidant, anti-inflammatory, and anticancer effects. Oral squamous cell carcinoma (OSCC) has a 5-year survival rate lower than that of most other carcinomas, and can create functional and aesthetic problems for the patient. New therapies for OSCC are necessary, and treatment using plant-derived natural substances has recently become a trend.

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Delphinidin is major anthocyanidin that is extracted from many pigmented fruits and vegetables. This substance has anti-oxidant, anti-inflammatory, anti-angiogenic, and anti-cancer properties. In addition, delphinidin strongly suppresses the migration and invasion of various cancer cells during tumorigenesis.

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Seed germination begins the growth phases of plants and its rate is affected not only by plant hormones, including abscisic acid (ABA), gibberellin (GA) and brassinosteroids (BRs), but also by environmental factors. In this study, we searched for additional chemical reagents that affect seed germination, using the det2-1 and ga1-3 mutants that showed reduced seed germination due to defective BR- or GA- biosynthesis, respectively. We found that the reducing reagent dithiothreitol (DTT) specifically enhanced seed germination of det2-1 compared with that of ga1-3.

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National reference standards (NRSs) for biologics are established through potency estimation by a multicenter joint study of standard materials used in the approval process for national lot release and quality control of vaccines, blood products, and other biologics. In this study, a stability evaluation was conducted to determine whether the potency of NRSs for six blood products was being maintained at a consistent level in Korea. The present study conducted real-time stability tests via / bioassay on NRSs for blood coagulation factor VIII concentrate (2nd standard), antithrombin concentrate, prekallikrein activator, anti-hepatitis B immunoglobulin, blood coagulation factor IX concentrate, and anti-tetanus human immunoglobulin, as well as a trend analysis using cumulative annual results.

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Cellular levels of Ca(2+) and reactive oxygen species (ROS) are maintained at low levels in the cytosol but fluctuate greatly when acting as second messengers to decode environmental and developmental signals. Phytohormones are primary signals leading to various changes in ROS or Ca(2+) signaling during synergistic and antagonistic cross-talk. In this study, we found that brassinosteroids (BRs), hormones involved in diverse plant developmental processes, promote ROS production.

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Background: The rapid and accurate detection of carbapenemase-producing Enterobacteriaceae (CPE) in clinical microbiology laboratories is essential for the treatment and control of infections caused by these microorganisms. This study was performed to evaluate the ability of the VITEK AST-N202 card to detect CPE isolates.

Materials And Methods: A total of 43 (Klebsiella pneumoniae, n = 37; Escherichia coli, n = 3; and Enterobacter cloacae, n = 3) CPE isolates and 79 carbapenemase-non-producing Enterobacteriaceae (CNE) isolates were included in this study.

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Metallo-β-lactamase-producing Pseudomonas aeruginosa (MPPA) is an important nosocomial pathogen that shows resistance to all β-lactam antibiotics except monobactams. There are various types of metallo-β-lactamases (MBLs) in carbapenem-resistant P. aeruginosa including Imipenemase (IMP), Verona integron-encoded metallo-β-lactamase (VIM), Sao Paulo metallo-β-lactamase (SPM), Germany imipenemase (GIM), New Delhi metallo-β-lactamase (NDM), Florence imipenemase (FIM).

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Single radial immunodiffusion (SRID) assay requires a reference antigen and an antibody to the hemagglutinin (HA) of an influenza vaccine. As it takes 2‑3 months to develop the reference antigen, vaccine development is delayed in cases of an influenza pandemic. In the present study, the measurement of the HA content of influenza vaccines was assessed using size exclusion high performance liquid chromatography (SE‑HPLC) for the rapid development of a pandemic vaccine.

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Non-protein amino acid, β-amino-n-butyric acid (BABA), has been involved in diverse physiological processes including seedling growth, stress tolerance and disease resistance of many plant species. In the current study, treatment of kimchi cabbage seedlings with BABA significantly reduced primary root elongation and cotyledon development in a dose-dependent manner, which adverse effects were similar to the plant response to exogenous abscisic acid (ABA) application. BABA was synergistically contributing ABA-induced growth arrest during the early seedling development.

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Arabidopsis RAV1, RAV1L and RAV2/TEM2 are Related to ABI3/VP1 (RAV) transcription factors that contain both plant-specific B3 and AP2 domains. RAV1 was known to be a negative regulator of growth and its transcript level was repressed by brassinolide (BL). In this study, we found that the expressions of RAV1, and its closest homologs RAV1L and RAV2 were also regulated by other plant hormones, and especially repressed significantly by BL and abscisic acid (ABA), which mediate various abiotic stress responses in plants.

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Methicillin-resistant Staphylococcus aureus (MRSA) is a dangerous microorganism, and creates serious medical problems. It causes many types of infections in humans and often acquires multi-drug resistance. In this study, silibinin was evaluated against 20 clinical isolates of MRSA, either alone or in combination with ampicillin or oxacillin, using a checkerboard assay.

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Background: This study was performed to investigate the prevalence of qnr genes in clinical isolates of Escherichia coli from Korea that produce extended-spectrum beta-lactamases (ESBLs).

Methods: During the period of May to June 2005, we collected clinical isolates of E. coli that were intermediate or resistant to ceftazidime and/or cefotaxime from 11 Korean hospitals.

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Costunolide, a natural sesquiterpene compound, has been known having cytotoxic and chemopreventive effects on various human cancer cells. In the present study, we examined the effects of costunolide on telomerase activity and on the components of telomerase in MCF-7 (wild-type p53) and MDA-MB-231 (mutant p53) cells. We found that costunolide inhibited the growth and telomerase activity of MCF-7 and MDA-MB-231 cells in a concentration- and time-dependent manner.

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