• International Journal of Oral Biology
• /
• v.46 no.1
• /
• pp.1-6
• /
• 2021

Since the outbreak of coronavirus disease 2019 (COVID-2019), the infection has spread worldwide due to the highly contagious nature of severe acute syndrome coronavirus (SARS-CoV-2). To manage SARS-CoV-2, the development of diagnostic assays that can quickly and accurately identify the disease in patients is necessary. Currently, nucleic acid-based testing and serology-based testing are two widely used approaches. Of these, nucleic acid-based testing with quantitative reverse transcription-PCR (RT-qPCR) using nasopharyngeal (NP) and/or oropharyngeal (OP) swabs is considered to be the gold standard. Recently, the use of saliva samples has been considered as an alternative method of sample collection. Compared to the NP and OP swab methods, saliva specimens have several advantages. Saliva specimens are easier to collect. Self-collection of saliva specimens can reduce the risk of infection to healthcare providers and reduce sample collection time and cost. Until recently, the sensitivity and accuracy of the data obtained using saliva specimens for SARS-CoV-2 detection was controversial. However, recent clinical research has found that sensitive and reliable data can be obtained from saliva specimens using RT-qPCR, with approximately 81% to 95% correspondence with the data obtained from NP and OP swabs. These data suggest that self-collected saliva is an alternative option for the diagnosis of COVID-19.

• YAKHAK HOEJI
• /
• v.51 no.4
• /
• pp.253-258
• /
• 2007

Bombycis corpus, a batryticated silkworm and white-stiff silkworm, is an oriental drug consisting of the dried larva of silkworm, dead and stiffened due to the infection of Beauveria. An peptidyl antimicrobial molecule was purified from B. corpus by reverse phase-column chromatography and HPLC. Its molecular weight was determined to be 2295.45 by using matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Its antimicrobial activity was diminished by trypsin digestion. It exhibited a broad antimicrobial spectrum against not only Gram-negative, but also Gram- positive bacteria. Furthermore, it was found to have an antimicrobial activity against vancomycin-resistant enterococci (VRE), methicillin-resistant S. arureus (MRSA), and vancomycin-intermediate resistant S. arureus (VISA). It may be a useful molecule for a new antibiotic development, especially against antibiotic resistant microbe. This substance may play a role in the defense system of this animal against Beauveria bassiana. This is the first report of a peptidyl antimicrobial substance from B. corpus.

• International Journal of Oral Biology
• /
• v.45 no.1
• /
• pp.1-7
• /
• 2020

Oral lichen planus (OLP) is a chronic inflammatory disease observed in approximately 0.5-2.2% of the population, and it is recognized as a premalignant lesion that can progress into oral squamous cell carcinoma (OSCC). The rate of malignant transformation is approximately 1.09-2.3%, and the risk factors for malignant transformation are age, female, erosive type, and tongue site location. Malignant transformation of OLP is likely related to the low frequency of apoptotic phenomena. Therefore, apoptosis-related genetic factors, like p53, BCL-2, and BAX are reviewed. Increased p53 expression and altered expression of BCL-2 and BAX were observed in OLP patients, and the malignant transformation rate in these patients was relatively higher. The involvement of microRNA (miRNA) in the malignant transformation of OLP is also reviewed. Because autophagy is involved in cell survival and death through the regulation of various cellular processes, autophagy-related genetic factors may function as factors for malignant transformation. In OLP, decreased levels of ATG9B mRNA and a higher expression of IGF1 were observed, suggesting a reduction in cell death and autophagic response. Activated IGF1-PI3K/AKT/mTor cascade may play an important role in a signaling pathway related to the malignant transformation of OLP to OSCC. Recent research has shown that miRNAs, such as miR-199 and miR-122, activate the cascade, increasing the prosurvival and proproliferative signals.

• Journal of Periodontal and Implant Science
• /
• v.54 no.4
• /
• pp.253-264
• /
• 2024

Purpose: This study investigated the association between dietary quality and the prevalence of periodontitis in older Korean adults (≥60 years of age) using data from the seventh Korea National Health and Nutrition Examination Survey (KNHANES VII, 2016-2018). Methods: Among the 16,489 KNHANES participants from 2016-2018, those aged ≥60 years were selected as the eligible population. After applying our exclusion criteria, 3,527 participants were included in the final study population. Periodontal status was measured using the Community Periodontal Index (CPI). To determine the association between dietary quality and the prevalence of periodontitis, analysis of variance, the chi-square (χ²) test, and logistic regression analysis were performed. Results: The population was divided into quartile groups and stratified by sex. The percentage of men and women with periodontitis was 54.34% and 42.74%, respectively. The quartile with higher Korean Healthy Eating Index scores had a lower percentage of people with periodontitis in both sexes. For men, only vegetable intake showed a significant difference between sub-groups with or without periodontitis, whereas, for women, the intake of fruits, milk, sweets, carbohydrates, and fats showed significant differences. There was a strong positive association between vegetable intake and periodontitis in men in the 3 models used in this study; model 3 had an adjusted odds ratio (aOR) of 1.367 (95% confidence interval [CI], 1.091-1.712). In women, a strong positive association with periodontitis was shown for sweets in all 3 models, with an aOR of 1.477 in model 3 (95% CI, 1.125-1.939). Conclusions: Dietary quality was inversely associated with the prevalence of periodontitis in Korean adults aged ≥60 years. Further comprehensive studies are needed to help establish nutrition and health policies for older adults in Korea.

• Journal of the Korea Concrete Institute
• /
• v.22 no.3
• /
• pp.297-303
• /
• 2010

The current encased-concrete deep corrugated steel plate has an arch type plate structure, which is a compressive strength-dominant structure that has a small moment due to its arch shape. Therefore, it increases the strength against compression by adding reinforcements to make concrete-filling spaces for increasing the compressive strength and forming cross sections that contain reinforced concrete. In this study, the safety factor of the new-concept encased-concrete bridge plate member was evaluated by comparing the compressive strength obtained from the compressive tests, flexural tests and the design compressive strength determined by using the Canadian Highway Bridge Design Code (CHBDC, 2003), which is a design standard for the encased-concrete bridge plate structures. The results of the safety factor evaluation using the design compressive strength and the test results showed that the safety factor was well above the appropriate value 2.0, which could be adjudged very conservative. If the safety factor based on this study results is considered and applied to the design, economical construction will be possible due to the reduced cross section and construction cost.

• The Journal of the Korea Contents Association
• /
• v.18 no.8
• /
• pp.73-81
• /
• 2018

In this paper, East Asian thoughts in Choi In-ho's novels have been studied based on Emmanuel Levinas' philosophical theories. He is a philosopher who dealt with the matter of subject formed through the encounter the others. The author of this paper quoted his ethics of responsibility, viewing that East-Asian thoughts put stress on the relationship with the others. The conclusions are like these; first, in the novel, Sang Do, there is a true relationship between the subject and the others thinking in the side of the other. Human relationship is like Sangsunyaksoo, which means when subject goes low, there appears a place the other can stay in. Second, in the novel Yoorim the essence of Neo-Confucianism shows up through Kyung thought, in which subject serves on the other in respect. That's like what Levinas said, "responsibility to others". Third, in the novel The Road without Road there appears Jinsokppuli, the central value of Korean Buddhists' Zen thoughts, meaning that you are not differentiated from me. In the times when the nation had been lost, Kyung Ho, who answered the call of people was a man who found what Levinas said, "the other who stays in me". As a conclusion the thoughts such as Sangsunyaksoo, Kyung, and Muae which show up in Choi In-ho's novels are connected with Levinas' ethics of responsibility and well shown as good examples of East Asian ethics.