Oral health of older Koreans by region and family status in 2020-2021.

OBJECTIVE: To describe the oral health of older people by region and family status using data from the National Health and Nutrition Survey. BACKGROUND: As the ageing of Korean society intensifies, health inequalities based on region and family status are also deepening. METHODS: Data from the 8th National Health and Nutrition Survey (2020-2021) conducted by the Korea Centers for Disease Control and Prevention were used, and a total of 3437 older people aged 65 or older were selected as study participants. Chewing discomfort and oral health behaviours were assessed by region and family status using multivariable logistic regression analysis with the complex sample survey design. RESULTS: We found an association between living alone and greater chewing discomfort. Residing in rural areas was also associated with a higher prevalence of this. In urban areas, chewing discomfort was 1.27 times higher among older people living alone than in those not living alone, while in rural areas, the discomfort was 1.52 times higher among the older people who lived alone. CONCLUSIONS: Region and family status were associated with greater chewing discomfort in older people. In Korean society, where the number of single-person older people households is increasing, along with the ageing population, attention to resolving the disparities in oral health in older people is needed.

Suppression of Pro-Inflammatory M1 Polarization of LPS-Stimulated RAW 264.7 Macrophage Cells by Fucoxanthin-Rich Sargassum hemiphyllum.

Macrophages play an important role in managing the onset and progression of chronic inflammatory diseases. The primary objective of this study is to explore the antioxidant potential and anti-inflammatory properties of Sargassum hemiphyllum ethanol extract (SHE) and its fraction. SHE and its five constituent fractions were assessed for overall antioxidant capabilities and inhibitory effects on LPS-induced inflammation by modulating macrophages polarization in both RAW 264.7 macrophages and bone-marrow-derived macrophages (BMDM). Among the organic solvent fractions of SHE, the ethyl acetate fraction displayed the highest total phenolic content and total antioxidant capacity. Notably, the n-hexane (Hex) fraction showed the most substantial suppression of LPS-induced tumor necrosis factor α secretion in BMDM among the five fractions of SHE. The SHE and Hex fraction significantly reduced the heightened expression of pro-inflammatory cytokines and inflammation-inducible enzymes induced by LPS in RAW 264.7 macrophages. In particular, the SHE and Hex fraction inhibited M1 macrophage polarization by reducing the mRNA expression of M1 macrophage markers in macrophages that were polarized toward the M1 phenotype. Furthermore, the SHE and Hex fraction attenuated the induction in nuclear factor E2-related factor 2 and its target genes, which was accompanied by an alteration in antioxidant gene expression in M1-polarized BMDM. The findings suggest that both SHE and its Hex fraction exhibit inhibitory effects on LPS-triggered inflammation and oxidative stress by modulating the polarization of M1 macrophages within macrophage populations.

Characterization of the Antimicrobial Activities of Trichoplusia ni Cecropin A as a High-Potency Therapeutic against Colistin-Resistant Escherichia coli.

The spread of colistin-resistant bacteria is a serious threat to public health. As an alternative to traditional antibiotics, antimicrobial peptides (AMPs) show promise against multidrug resistance. In this study, we investigated the activity of the insect AMP Tricoplusia ni cecropin A (T. ni cecropin) against colistin-resistant bacteria. T. ni cecropin exhibited significant antibacterial and antibiofilm activities against colistin-resistant Escherichia coli (ColREC) with low cytotoxicity against mammalian cells in vitro. Results of permeabilization of the ColREC outer membrane as monitored through 1-N-phenylnaphthylamine uptake, scanning electron microscopy, lipopolysaccharide (LPS) neutralization, and LPS-binding interaction revealed that T. ni cecropin manifested antibacterial activity by targeting the outer membrane of E. coli with strong interaction with LPS. T. ni cecropin specifically targeted toll-like receptor 4 (TLR4) and showed anti-inflammatory activities with a significant reduction of inflammatory cytokines in macrophages stimulated with either LPS or ColREC via blockade of TLR4-mediated inflammatory signaling. Moreover, T. ni cecropin exhibited anti-septic effects in an LPS-induced endotoxemia mouse model, confirming its LPS-neutralizing activity, immunosuppressive effect, and recovery of organ damage in vivo. These findings demonstrate that T. ni cecropin exerts strong antimicrobial activities against ColREC and could serve as a foundation for the development of AMP therapeutics.

Rhamnetin, a Natural Flavonoid, Ameliorates Organ Damage in a Mouse Model of Carbapenem-Resistant Acinetobacter baumannii-Induced Sepsis.

In sepsis, the persistence of uncontrolled inflammatory response of infected host cells eventually leads to severe lung and organ failure and, ultimately, death. Carbapenem-resistant Acinetobacter baumannii (CRAB), causative bacteria of sepsis and lung failure in acute cases, belongs to a group of critical pathogens that cannot be eradicated using the currently available antibiotics. This underlines the necessity of developing new modes of therapeutics that can control sepsis at the initial stages. In this study, we investigated the anti-inflammatory activities in vitro and in vivo and the antiseptic effects of rhamnetin, a naturally occurring flavonoid. We found that among its isoforms, the potency of rhamnetin was less explored but rhamnetin possessed superior anti-inflammatory activity with least cytotoxicity. Rhamnetin showed significant anti-inflammatory effects in lipopolysaccharide-, CRAB-, and Escherichia coli (E. coli)-stimulated mouse macrophages by inhibiting the release of interleukin-6 and nitric oxide. In a mouse model of sepsis infected with clinically isolated CRAB or E. coli, rhamnetin significantly reduced the bacterial burden in the organs. In addition, normalized pro-inflammatory cytokine levels in lung lysates and histological analysis of lung tissue indicated alleviation of lung damage. This study implies that a potent natural product such as rhamnetin could be a future therapeutic for treating carbapenem-resistant gram-negative sepsis.

Comparative effectiveness of bisphosphonate treatments for the prevention of re-fracture in glucocorticoid-induced osteoporosis: protocol for a systematic review and meta-analysis.

BACKGROUND: Long-term usage of glucocorticoids results in a loss of bone mass and a higher risk of fracture, and the most common cause of secondary osteoporosis is glucocorticoid-induced osteoporosis (GIOP). For preventing GIOP, bisphosphonate (BP) is widely used. However, analysis on BP's effect on the prevention of re-fracture is insufficient. The purpose of the present study is to evaluate the comparative treatment effect and prevention of re-fracture according to the type of BP in GIOP as the basis for a reliable clinical strategy for patients. METHODS AND ANALYSIS: We will search electronic databases of the PubMed, Cochrane Library and EMBASE using a comprehensive search strategy in December 2021 with no language restriction. Randomised controlled trials (RCTs), quasi-RCTs, controlled trials and cohort studies evaluating the effectiveness of BP to the patients with GIOP will be included in this study. The primary outcome will be the incidence of hip, vertebral and other fractures. The secondary outcome will include percentage changes on the bone mineral density and incidence of re-fracture. Assessing risk of bias for included studies is done using the Cochrane Risk of Bias tool and Risk Of Bias In Non-randomized Studies-of Intervention tool. If quantitative synthesis is possible, a meta-analysis will be performed. A subgroup analysis will be conducted to compare re-fracture rate on the patients with GIOP who experience previous fractures. This study's result will provide evidence for the effectiveness of BP in the prevention of re-fracture on patients with GIOP. ETHICS AND DISSEMINATION: The results will be disseminated through publishing in a peer-reviewed journal or public presentations. Ethical approval is not required as this is a systematic review of publicly available data. PROSPERO REGISTRATION NUMBER: CRD42022343787.

Association between Dental Caries and Handgrip Strength: In a Population-Based Study in Korea (KNHANES 2016-2018).

This study aimed to verify the relationship between handgrip strength and oral health using data from the Korea National Health and Nutrition Examination Survey, representing Korean adults. Data from the seventh survey (2016−2018) conducted by the Korea Centers for Disease Control and Prevention were utilized, and 10,607 final study participants were recruited according to the selection and exclusion criteria. A complex sample logistic regression analysis was performed to confirm the relationship between handgrip strength and dental caries according to the sex of the study participants. On analyzing the correlation in men, "C1 (DMFT: 11−32)," when compared to "C4 (DMFT: 0−3)," in Model 1 without adjustment for potential confounders, was 2.92 (95% confidence interval [CI]: 2.15−3.97) times more likely to be associated with lower handgrip strength, and a statistically significant result was detected (p < 0.001). Additionally, significant odds ratios (ORs) were confirmed for all adjusted models. In women, the ORs in Model 1 without adjustment for potential confounders were 1.41 times (95% CI: 1.14−1.75) and demonstrated a significant result; however, the results were not significant in all adjusted models 2−4. Resultantly, a significant association was detected between dental caries and handgrip strength in Korean adults.

Relationship between the Toothbrushing Behavior and Hand Hygiene Practices of Korean Adolescents: A Study Focused on the 15th Korea Youth Risk Behavior Survey Conducted in 2019.

Hand hygiene is one of the most important measures available to prevent infectious diseases such as COVID-19, and it is recommended that individuals wash their hands periodically before and after meals, after using toilets, before preparing food at home, at schools, and in public places. The aim of this study was to investigate the relationship between oral hygiene and hand hygiene in Korean adolescents. Data from 57,303 adolescents who participated in the 2019 Korea Youth Risk Behavior web-based survey were analyzed to determine the relationship between oral hygiene and hand hygiene. A complex sample logistic regression analysis was performed to determine association between toothbrushing behavior and handwashing practices. According to the results of this study, adolescents who brushed their teeth after lunch were 1.48 times more likely to practice handwashing before lunch than were those who did not brush their teeth after lunch (p < 0.001). In addition, the odds ratios adjusted for gender, grade, school type, and residence were found to be 1.87 (p < 0.001). Moreover, these adjusted odds ratios were higher in students who received personal hygiene education (OR: 1.98, p < 0.001). Oral hygiene practices were found to be related to personal hygiene, as assessed by handwashing, in Korean adolescents. Additional studies are needed to develop ways of improving the hygiene and health of adolescents.

The effect of comprehensive oral care program on oral health and quality of life in patients undergoing radiotherapy for head and neck cancer: A quasi-experimental case-control study.

OBJECTIVES: The purpose of this study is to investigate the effect of the comprehensive oral care program on oral health status and symptoms in head and neck cancer (HNC) patients undergoing radiotherapy. METHODS: This was a quasi-experimental study using a non-equivalent control group in non-synchronized design. All participants including control and experimental group were asked for the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire H&N35 (EORTC QLQ-H&N35) and given an oral health education 4 times at baseline, immediate postradiotherapy, 3 months after radiotherapy, and 6 months after radiotherapy. In each visit except for final, the experimental group was given fluoride varnish application and fluoride mouth rinsing solution for daily use. Oral health examination for dental caries, plaque score (PS), bleeding on probing (BOP), and salivary flow rate was performed in baseline and 6 months after radiotherapy. Statistical analyses were done by paired t-tests and mixed ANCOVA repeated-measures analysis. RESULTS: From November 1, 2013 to October 31, 2015, a total 61 patients undergoing radiotherapy for HNC cancer were enrolled (30 in control and 31 in experimental groups). Decrease in salivary flow rate was comparable between 2 groups. Dental caries increased in control group (P = .006); PS and BOP were decreased in experimental group (P < .001 and .004, respectively). Experimental group showed lower swallowing, speech problems, and less sexuality scores in EORTC QLQ-H&N35 than control group. CONCLUSION: We found improvement in oral health and the quality of life in HNC patients with comprehensive oral care intervention by dental professionals. Communicating and cooperating between the healthcare and dental professionals is needed to raise the quality of health care services for HNC patients receiving radiotherapy.

Association between low potassium intake and the number of teeth in Korean adults: based on the national data (2013-2015).

General health and oral health are very closely related. This study aimed to analyze the nutritional factors associated with the number of present teeth in Korean elderly adults. A total of 6,356 individuals were surveyed from the sixth Korean National Health and Nutrition Examination Survey conducted from 2013-2015. The number of existing teeth was divided into three categories: 0-10, 11-20, and over 21, and the nutrition survey covers eating habits, food frequency and food intake using face-to-face interviews. Multiple logistic regression analysis was performed to evaluate the association between nutrient intake and the number of existing teeth after adjusting for socio-demographic factors and general and oral health behaviors and status. As age increases, the number of teeth decreases. Individuals with more teeth had a significantly higher mean daily intake of protein, calcium, phosphorus, potassium and riboflavin (p < 0.05). After adjusting for sociodemographic factors in model 1 and the lower number of teeth in model 2, the strength of the association between the number of teeth and daily calcium intake remained significant. Statistically significant associations were present for dietary potassium intake in models 1 and 2 and in the 11-20 teeth group in model 3 (p < 0.05). We demonstrated a significant association between calcium and potassium intake and the number of teeth.

The Distinct Role of Tcfs and Lef1 in the Self-Renewal or Differentiation of Mouse Embryonic Stem Cells.

BACKGROUND AND OBJECTIVES: Tcfs and Lef1 are DNA-binding transcriptional factors in the canonical Wnt signaling pathway. In the absence of ß-catenin, Tcfs and Lef1 generally act as transcriptional repressors with co-repressor proteins such as Groucho, CtBP, and HIC-5. However, Tcfs and Lef1 turn into transcriptional activators during the interaction with ß-catenin. Therefore, the activity of Tcfs and Lef1 is regulated by ß-catenin. However, the intrinsic role of Tcfs and Lef1 has yet to be examined. The purpose of this study was to determine whether Tcfs and Lef1 play differential roles in the regulation of self-renewal and differentiation of mouse ES cells. METHODS AND RESULTS: Interestingly, the expression of Tcfs and Lef1 was dynamically altered under various differentiation conditions, such as removal of LIF, EB formation and neuronal differentiation in N2B27 media, suggesting that the function of each Tcf and Lef1 may vary in ES cells. Ectopic expression of Tcf1 or the dominant negative form of Lef1 (Lef1-DN) contributes to ES cells to self-renew in the absence of leukemia inhibitory factor (LIF), whereas ectopic expression of Tcf3, Lef1 or Tcf1-DN did not support ES cells to self-renew. Ectopic expression of either Lef1 or Lef1-DN blocked neuronal differentiation, suggesting that the transient induction of Lef1 was necessary for the initiation and progress of differentiation. ChIP analysis shows that Tcf1 bound to Nanog promoter and ectopic expression of Tcf1 enhanced the transcription of Nanog. CONCLUSIONS: The overall data suggest that Tcf1 plays a critical role in the maintenance of stemness whereas Lef1 is involved in the initiation of differentiation.

Early-life socioeconomic position and periodontal status in Korean adults.

OBJECTIVES: The aim of this study was to assess the association between different life-course socioeconomic positions (SEPs) and periodontitis in a large representative sample of the Korean population. METHODS: With data from Korean adults aged 30-59, periodontitis was assessed with the community periodontal index. Parental education, own education, and income as indicators of early childhood SEP, adolescence SEP, and adulthood SEP, respectively, were categorized by four groups (1-4). The association between the different life-course SEPs and periodontitis was estimated according to three different life-course models: individual impact of the three SEPs, cumulative impact by the sum of the three SEP values (sum ranges 3-12), and the pathways of the three SEPs through lifetime to the periodontitis. Covariates were demographic factors, health behaviors, and health problems. The prevalence ratios (PRs) and relative index of inequality (RII) for periodontitis were obtained. RESULTS: In an individual impact model, significant associations of each SEP with periodontitis were found after adjusting for all covariates (RII = 1.16 for parental education, 1.19 for own education, and 1.27 for income). For a cumulative impact model, there were higher risks for periodontitis as the sum of the three SEP values increased (RII = 1.51). For the intergenerational social mobility model, prevalence of current periodontal disease was highest in the persistently low group. (RII = 1.54 and PR = 1.51). CONCLUSIONS: These results show that the individual and cumulative SEPs measured by the parental education, own education, and income were independently associated with the periodontal status of Korean adults. The pathway and cumulative hypotheses for the life-course SEP effects on periodontitis could be salient in oral epidemiology.

Association between adult height and tooth loss in a representative sample of Koreans.

OBJECTIVES: Evidence suggests that taller individuals have better health than that of shorter individuals. However, evidence for links to tooth loss is scarce. The aim of this study was to examine the association between adult height and tooth loss and to examine the roles of covariates in explaining the association in different birth cohorts in Korea. METHODS: Using data from the Fourth and Fifth Korea National Health and Nutritional Examination Survey (KNHANES IV and V), the subjects were grouped into two birth cohorts based on their historical context: born from 1920 to 1945 and 1946 to 1962. The dependent variables were loss of 8 or more teeth and total tooth loss (edentulism), while the independent variable was the height quartile. Demographic factors (survey year, age, and gender), early childhood/adult socioeconomic status (SES) (father's education, own education, income, and place of residence), health behaviors (cigarette smoking, binge drinking, frequency of toothbrushing, and regular dental visit), and health problems (diabetes and hypertension) were included in a series of analytical models. RESULTS: The survey year-, age-, and gender-adjusted prevalence ratios (PR) of the loss of 8 or more teeth for the shortest quartile were 1.23 (95% confidence intervals, CI: 1.13-1.35) for the 1920-1945 birth cohorts and 1.39 (95% CI: 1.20-1.62) for the 1946-1962 birth cohorts. The PRs for edentulousness were 1.64 (95% CI: 1.34-2.02) for the 1920-1945 birth cohorts and 2.26 (95% CI: 1.31-3.91) for the 1946-1962 birth cohorts. These associations were moderately attenuated after adjusting for own education but still significant in the fully adjusted models. After full adjustment for the covariates, those in the shortest height quartiles in the relatively young birth cohorts (1946-1962 birth cohorts) had a 1.93 (95% CI: 1.09-3.43) times greater prevalence of edentulism than that of their tallest counterparts. CONCLUSIONS: Given that adult height reflects early-life conditions, independent associations between height and tooth loss support the view that early-life circumstances significantly influence oral health outcomes in later life.

Exploring the determinants of secular decreases in dental caries among Korean children.

OBJECTIVE: The aim of this study was to determine the contributions of sealant and water fluoridation to the time trends in dental caries from 2003 to 2010. MATERIALS AND METHODS: Data were from three waves of the Korean National Oral Health Surveys between 2003 and 2010, including a total of 23 059 children (11 889 boys and 11 170 girls) aged 8, 10, and 12 years. The impacts of sealant and water fluoridation on dental caries were obtained by logistic regression for each age group of children. The contributions of sealant and water fluoridation to the time trends in the prevalence of dental caries were examined by a series of logistic regression models, and changes in the adjusted odds ratios for each survey year were also calculated. RESULTS: Over the past 7 years, the prevalence of dental caries decreased dramatically. Although sealant had a significant impact on dental caries in each survey year, remarkable decreases in dental caries from 2003 to 2010 were not explained by the secular changes in the dental sealant or water fluoridation factor. CONCLUSION: We observed important population declines in dental caries in Korea in children aged 8-12 years; however, the likely causes for these secular trends remain to be determined.

Smoking induced heavy metals and periodontitis: findings from the Korea National Health and Nutrition Examination Surveys 2008-2010.

AIM: Exposure to hazardous heavy metals such as cadmium and lead may contribute to increased oxidative stress and inflammation in the periodontal tissue. We aimed to evaluate the association between serum cadmium and lead levels and periodontitis. MATERIALS & METHODS: Pooled cross-sectional data from the Korea National Health and Nutrition Examination Surveys 2008-2010 were used. Periodontitis was defined as WHO community periodontal index. Active smokers were defined as self-reported current smokers or those with measured urine cotinine ≥164 ng/ml measurements. Serum cadmium and lead levels were measured using graphite furnace atomic absorption spectrometry. Multiple logistic regression analysis was used to estimate the odds ratios (OR) for periodontitis. RESULTS: The mean cadmium and lead levels were significantly higher in the periodontitis group compared with control population. A progressive increase in serum heavy metals were found as the number of sextants with periodontitis. The ORs for periodontitis were significantly associated with serum cadmium (OR = 1.37; 95% CI 1.00-1.87) and lead levels (OR = 1.60; 95% CI 1.15-2.21). The association between periodontitis and smoking was attenuated after adjusting for serum cadmium concentration. CONCLUSIONS: We demonstrated a significant association between periodontitis and serum cadmium and lead concentrations. Cadmium appeared to partially mediate the association between smoking and periodontitis.