TAS2R38 bitterness receptor genetic variation is associated with diet quality in Koreans.

Genetic variation in the bitter taste receptor gene taste receptor type 2, member 38 (TAS2R38) is associated with an individual's bitter taste sensitivity, food preference and consumption, which may also influence overall diet quality. This study aims to determine whether the TAS2R38 bitter taste receptor genetic variation is associated with overall diet quality using the Korean Healthy Eating Index (KHEI). A total of 41,839 individuals from the Korean Genome and Epidemiology Study were analyzed for their TAS2R38 diplotypes (rs713598, rs1726866, and rs10246939), general characteristics, and KHEI scores by obesity status. Results revealed that in the non-obese group, individuals with the AVI/AVI diplotype had a significantly higher score of 'ratio of white meat to red meat' than individuals with the PAV/* diplotype (3.89 ± 3.23 vs. 3.79 ± 3.18, adjusted p = 0.029). However, obese individuals with the PAV/* diplotype showed a significantly higher level of the mean score of 'moderation' (19.32 ± 5.82 vs. 18.92 ± 5.80, adjusted p = 0.026) and total KHEI score (61.07 ± 12.19 vs. 60.52 ± 12.29, adjusted p = 0.008) than those with the AVI/AVI diplotype. Finally, an interactive effect between bitterness genetic variation and obesity level was observed in those scores of 'ratio of white meat to red meat' (adjusted p = 0.007), 'moderation' (adjusted p = 0.013), and total KEHI (adjusted p = 0.007). In conclusion, TAS2R38 genetic variation is associated with overall diet quality in Koreans, which is more evident in the obese group.

Genetic variation in TAS2R38 bitterness receptor is associated with body composition in Korean females.

Bitterness-receptor gene TAS2R38 is associated with taste sensitivity and dietary behaviour, and is known to play a critical role in adiposity. However, evidence regarding body composition from a large cohort is lacking. This study aimed to ascertain whether TAS2R38 rs10246939 C > T bitterness genetic variation is associated with body composition in Korean individuals. The TAS2R38 rs10246939 genotypes, anthropometric measurements, and body composition of 1,843 males and 1,801 females from the Korean Genome and Epidemiology Study were analysed. Findings suggested that there was a significant difference in body fat components by TAS2R38 genotype. Furthermore, the bitterness genotype exhibited a positive association with adiposity markers in females. The TT genotype showed greater body mass index, body fat percentage, and degree of obesity than those with the C allele. However, such an association was not observed in males. In conclusion, this study suggests that TAS2R38 rs10246939 is associated with fat tissue markers in Korean females.

Genetic variation in CD36 is associated with dietary intake in Korean males.

Fat is one of the six types of taste. Perceived taste intensity could affect the preference for a food and whether or not it is consumed. Cluster of differentiation 36 (CD36) translocates fatty acids on the cellular membrane and is involved in the oral fat-sensing mechanism. Therefore, genetic variation rs1761667 in CD36 is known to be associated with the perception of fat taste and, hence, its dietary intake. This study examined whether CD36 rs1527479 T>C, a proxy of rs1761667, is associated with fat intake and related dietary behaviour in Koreans. Using the data of the Ansan/Ansung Study, a part of the Korean Genome Epidemiology Study, the association of rs1527479 with the intake of macronutrients, including fat and selected foods, and fat-related dietary behaviours were investigated in 3194 males and 3425 females grouped by their degree of obesity. The findings suggested that rs1527479 did not have a meaningful effect on the intake of fat or other macronutrients or on the selection of food among non-obese females and males. However, in males with obesity, the genetic variation showed a significant association with vegetable intake. Obese males with the mutant CC genotype had substantially lower cruciferous vegetable consumption (adjusted P = 0·0015) than individuals with the TT and CT genotypes. Rs1527479 had no significant effect on the frequency of consuming fried foods or commonly used types of seasoning and cooking oils. In conclusion, CD36 genetic variation was associated with the intake of cruciferous vegetables but not fat intake in obese Korean males.

TAS1R2 sweet taste receptor genetic variation and dietary intake in Korean females.

Taste receptor type 1, member 2 (TAS1R2) controls the oral sensing of sweetness. Genetic variations in TAS1R2 have been shown to be associated with differential sweetness intensity and varying carbohydrate intake levels among individuals. This study examined whether rs7534618 A > C in TAS1R2 is associated with dietary behavior and energy nutrient intake in Korean females. A cross-sectional design utilizing data from the Multi-Rural Communities Cohort Study, which was a nationwide epidemiological research project in Korea, was applied in this study. In total, 2198 females were analyzed to evaluate the differences in macronutrient intake levels and intake of carbohydrate-rich and sweet-tasting foods between the rs7534618 genotypes. The findings suggest that individuals with the CC minor genotype tended to have lower carbohydrate but higher fat intake than subjects with the A* genotype (p = 0.035 and p = 0.042, respectively). Subjects with the CC genotype also exhibited less intake of total grains but greater intake of bread than those with the A* genotype (p = 0.017 and p = 0.006, respectively). However, these observed associations were statistically modest (false discovery rate adjusted p > 0.05). In conclusion, TAS1R2 rs7534618 is not a decisive genetic modifier of nutrition and dietary intake in Korean females. However, given the paucity of studies, these putative associations between the TAS1R variation and dietary intake may be referred for further sensory genetic studies in Koreans.

TAS2R38 Bitterness Receptor Genetic Variation and Risk of Gastrointestinal Neoplasm: A Meta-Analysis.

Genetic variation in TAS2R38 bitterness taste receptor could alter the efficacy of molecular sensing, hence may be associated with cancer risk. Thus, we performed a meta-analysis to verify the association between the risk of gastrointestinal (GI) neoplasm and TAS2R38 genetic variation. Studies with TAS2R38 diplotype distribution and GI neoplasm phenotypes were searched from PubMed, EMBASE and SCOPUS, and five articles including eight studies were finally selected. The association between diplotype and neoplasm risk was estimated with summarized odds ratios (ORs) and 95% confidence intervals (CIs), applying of fixed- or random-effects models. The findings suggested TAS2R38 diplotype was not associated with GI neoplasms susceptibility [AVI vs. PAV: OR = 1.03 (95%CI: 0.97-1.09), AVI/PAV vs. PAV/PAV: OR = 1.05, (95%CI: 0.94-1.17), AVI/* vs. PAV/PAV: OR = 1.04 (95%CI: 0.94-1.16)]. Because of the presence of heterogeneity under the two genetic models (AVI/AVI vs. PAV/PAV and AVI/AVI vs. PAV/*), further subgroup analyses by ethnicity and neoplasm type were performed. However, results failed to show the neoplasm risk was altered by diplotype. In conclusion, the meta-analysis indicates that TAS2R38 diplotype minimally modified the GI neoplasm risk. Given the limited study size and resources, further well-designed and larger studies are required to validate the true effect of TAS2R38 polymorphisms on neoplasm risk.

Genetic variations in taste perception modify alcohol drinking behavior in Koreans.

The sensory components of alcohol affect the onset of individual's drinking. Therefore, variations in taste receptor genes may lead to differential sensitivity for alcohol taste, which may modify an individual's drinking behavior. This study examined the influence of genetic variants in the taste-sensing mechanism on alcohol drinking behavior and the choice of alcoholic beverages. A total of 1829 Koreans were analyzed for their alcohol drinking status (drinker/non-drinker), total alcohol consumption (g/day), heavy drinking (≥30 g/day) and type of regularly consumed alcoholic beverages. Twenty-one genetic variations in bitterness, sweetness, umami and fatty acid sensing were also genotyped. Our findings suggested that multiple genetic variants modified individuals' alcohol drinking behavior. Genetic variations in the T2R bitterness receptor family were associated with overall drinking behavior. Subjects with the TAS2R38 AVI haplotype were less likely to be a drinker [odds ratio (OR): 0.75, 95% confidence interval (CI): 0.59-0.95], and TAS2R5 rs2227264 predicted the level of total alcohol consumption (p = 0.01). In contrast, the T1R sweet and umami receptor family was associated with heavy drinking. TAS1R3 rs307355 CT carriers were more likely to be heavy drinkers (OR: 1.53, 95% CI: 1.06-2.19). The genetic variants were also associated with the choice of alcoholic beverages. The homo-recessive type of TAS2R4 rs2233998 (OR: 1.62, 95% CI: 1.11-2.37) and TAS2R5 rs2227264 (OR: 1.72, 95% CI: 1.14-2.58) were associated with consumption of rice wine. However, TAS1R2 rs35874116 was associated with wine drinking (OR: 0.65, 95% CI: 0.43-0.98) and the consumption level (p = 0.04). These findings suggest that multiple genetic variations in taste receptors influence drinking behavior in Koreans. Genetic variations are also responsible for the preference of particular alcoholic beverages, which may contribute to an individual's alcohol drinking behavior.

Performance Evaluation of the STANDARD i-Q COVID-19 Ag Test with Nasal and Oral Swab Specimens from Symptomatic Patients.

We evaluated the diagnostic performance of the STANDARD i-Q COVID-19 Ag Test, which was developed to detect viral antigens, using nasal and oral swabs. Sixty positive and 100 negative samples were analyzed. We determined the distribution of the Ct values according to the day of sample collection after symptom onset, the diagnostic performance of the total samples and subgroups separated by Ct value or time of sample collection, and the Ct value at which maximal accuracy was expected. No differences were observed in Ct values, except for the samples obtained on the day of symptom onset. The diagnostic sensitivity and specificity of the oral swabs were 75.0 and 100.0%, respectively, whereas those of the nasal swabs were 85.0 and 98.0%, respectively. The sensitivity was higher in samples with a high viral load collected earlier than those collected later, although the difference was not significant. False-negative results were confirmed in all samples with a Ct value ≥ 30.0. These results indicate that tests using oral and nasal swabs are helpful for diagnosing acute symptomatic cases with suspected high viral loads. Our tests exhibited relatively low sensitivity but high specificity rates, indicating the need to assess negative antigen test results.

Vitamin C-related nutrient-nutrient and nutrient-gene interactions that modify folate status.

PURPOSE: Folate-related nutrient-nutrient and nutrient-gene interactions modify disease risk; we therefore examined synergistic relationships between dietary folic acid, vitamin C and variant folate genes with respect to red cell folate status. METHODS: Two hundred and twelve subjects were examined using chemiluminescent immunoassay, PCR and food frequency questionnaire to determine red cell and serum folate, 14 folate gene polymorphisms, dietary folate (natural and synthetic) and vitamin C. RESULTS: When examined independently, synthetic PteGlu correlates best with red cell folate at higher levels of intake (p = 0.0102), while natural 5CH(3)-H(4)-PteGlu(n) correlates best with red cell folate at lower levels of intake (p = 0.0035). However, dietary vitamin C and 5CH(3)-H(4)-PteGlu(n) interact synergistically to correlate with red cell folate at higher levels of intake (p = 0.0005). No interaction between dietary vitamin C and PteGlu was observed. This 'natural' nutrient-nutrient interaction may provide an alternative to synthetic PteGlu supplementation that is now linked to adverse phenomena/health outcomes. On its own, vitamin C also correlates with red cell folate (p = 0.0150) and is strongly influenced by genetic variation in TS, MTHFR and MSR, genes critical for DNA and methionine biosynthesis that underpin erythropoiesis. Similarly, dietary vitamin C and 5CH(3)-H(4)-PteGlu(n) act synergistically to modify red cell folate status according to variation in folate genes: of note, heterozygosity for 2R3R-TS (p = 0.0181), SHMT (p = 0.0046) and all three MTHFR SNPs (p = 0.0023, 0.0015 and 0.0239 for G1793A, C677T and A1298C variants, respectively) promote a significant association with red cell folate. Again, all these genes are critical for nucleic acid biosynthesis. Folate variants with the strongest independent effect on folate status were C677T-MTHFR (p = 0.0004) and G1793A-MTHFR (p = 0.0173). CONCLUSIONS: 5CH(3)-H(4)-PteGlu(n) assimilation and variant folate gene expression products may be critically dependent on dietary vitamin C.

Food Insecurity Is Associated with Dietary Consumption during the COVID-19 Pandemic: Data from the Korea National Health and Nutrition Examination Survey 2019-2020.

Coronavirus disease 2019 (COVID-19) has become a pandemic and has affected people's dietary behaviors, including food insecurity. This study aimed to ascertain whether COVID-19 may alter the prevalence of food insecurity, and if such food security status may be associated with dietary intake among Koreans. The general characteristics, dietary intake and food security status data in the Korea National Health and Nutrition Examination Survey VIII (2019~2020) were analyzed. The prevalence of food insecurity and food group and nutrient consumption by food security status were analyzed before (2019) and after the start of the pandemic (2020). Findings suggested 4.3% of Koreans experienced food insecurity during the first year of the pandemic, yet it did not differ from that in the year before the pandemic. Before COVID-19, there was no significant difference in food group or nutrition consumption by food security status. However, in 2020, the fruit and vitamin C intake of the food-insecure group was significantly lower than that of the food-secure group. Additionally, the food-insecure group's ratio of subjects who did not meet the recommended level of fruits and the vitamin was higher compared to that of the secure group. In conclusion, COVID-19 did not affect food insecurity status, but did have a negative influence on dietary intake for food-insecure Koreans.

Bitter Taste Receptor TAS2R38 Genetic Variation (rs10246939), Dietary Nutrient Intake, and Bio-Clinical Parameters in Koreans.

Differential bitterness perception associated with genetic polymorphism in the bitter taste receptor gene taste 2 receptor member 38 (TAS2R38) may influence an individual's food preferences, nutrition consumption, and eventually chronic nutrition-related disorders including cardiovascular disease. Therefore, the effect of genetic variations on nutritional intake and clinical markers needs to be elaborated for health and disease prevention. In this study, we conducted sex-stratified analysis to examine the association between genetic variant TAS2R38 rs10246939 A > G with daily nutritional intake, blood pressure, and lipid parameters in Korean adults (males = 1,311 and females = 2,191). We used the data from the Multi Rural Communities Cohort, Korean Genome and Epidemiology Study. Findings suggested that the genetic variant TAS2R38 rs10246939 was associated with dietary intake of micronutrients including calcium (adjusted p = 0.007), phosphorous (adjusted p = 0.016), potassium (adjusted p = 0.022), vitamin C (adjusted p = 0.009), and vitamin E (adjusted p = 0.005) in females. However, this genetic variant did not influence blood glucose, lipid profile parameters, and other blood pressure markers. These may suggest that this genetic variation is associated with nutritional intake, but its clinical effect was not found. More studies are needed to explore whether TAS2R38 genotype may be a potential predictive marker for the risk of metabolic diseases via modulation of dietary intake.

Genetic variant rs9939609 in FTO is associated with body composition and obesity risk in Korean females.

INTRODUCTION: The fat mass and obesity-associated (FTO) gene is a significant locus in obesity. However, the association between FTO genetic variants and body composition has not been fully elucidated. RESEARCH DESIGN AND METHODS: This observational study examined the associations of FTO rs9939609 T>A with obesity and body composition markers in Koreans. A total of 6474 participants from the Korean Genome and Epidemiology Study were analyzed for their general characteristics, body composition and FTO genotype with a sex-stratified approach. RESULTS: Females with the obesity risk A allele showed significantly greater body weight, hip circumference, and body mass index and were at a 1.28-fold higher risk of obesity (95% CI=1.088 to 1.507) than those with the TT genotype. Analyses of body composition also showed that females with the A allele had a greater body fat mass and percentage, abdominal fat percentage, and degree of obesity, and this association and FTO genetic variation and adiposity was observed in females, especially aged under 50 years. However, the effect of the variant allele on non-fat tissue markers was not evident in females and was not associated with any parameters examined in males. CONCLUSIONS: The FTO rs9939609 variant is associated with body composition in Koreans, especially body fat markers in females. These results support that the FTO rs9939609 variant is a genetic risk factor in the etiology of obesity.

Pediatric humoral immune responses and infection risk after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and two-dose vaccination during SARS-CoV-2 omicron BA.5 and BN.1 variants predominance in South Korea.

Background: Humoral immune responses and infection risk after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) vaccination during the Omicron BA.5 and BN.1 variants predominant period remains unexplored in pediatric population. Methods: We examined anti-spike (anti-S) immunoglobulin G (IgG) responses in a total of 986 children aged 4-18 years who visited outpatient clinics between June 2022 and January 2023, with a history of SARS-CoV-2 infection alone, completed two doses of COVID-19 vaccination alone, vaccine-breakthrough infection (i.e., infection after the single dose of vaccination), and no antigenic exposure. Furthermore, to determine SARS-CoV-2 infection risk, the incidence of newly developed SARS-CoV-2 infection was investigated up to March 2023. Results: The anti-S IgG levels in the 'vaccine-breakthrough infection' group exceeded those in the 'infection alone' and 'vaccination alone' groups (both P <0.01). Furthermore, the 'vaccination alone' group experienced more rapid anti-S IgG waning than the 'infection alone' and 'vaccine-breakthrough infection' groups (both P <0.01). We could not identify newly developed SARS-CoV-2 infection in the 'vaccine-breakthrough infection' group. Conclusion: Our findings suggest that hybrid immunity, acquired from SARS-CoV-2 infection and COVID-19 vaccination, was a potentially higher and longer-lasting humoral immune response and protected against SARS-CoV-2 infection in pediatric population during Omicron BA.5 and BN.1 variants predominant.

Genetic variation rs1121980 in the fat mass and obesity-associated gene (FTO) is associated with dietary intake in Koreans.

Background: Fat mass and obesity-associated gene (FTO) is a well-known gene associated with body weight and obesity risk. Recent studies have suggested that genetic variations in FTO may play a role in the regulation of food preference and consumption. However, little is known with respect to Asian populations. Objective: This study examined whether rs1121980 C > T in FTO is associated with food intake in Koreans. Design: This study was performed using data from the Korean Genome and Epidemiology Study (Ansan/Ansung cohort). Dietary intake was determined using the semi-food frequency questionnaire, and the FTO rs1121980 genotypes of 6,262 individuals (3,049 males and 3,213 females) were analyzed along with sex and body mass index (BMI). Result: Genetic variation did not show a significant association with the population's energy-nutrient intake. However, female T allele carriers with BMI ≥ 25 consumed more blue fish and coffee, and their coffee creamer consumption was decisively higher than that of T allele non-carriers (P adjusted = 0.004). In males, the presence of the T allele showed a putative association with the consumption of sweets, snacks, and coffee creamer by the BMI level. Conclusion: The FTO rs1121980 variation was associated with a preference for foods particularly high in fat (e.g. coffee creamer, blue fish, sweets, and snacks) in Koreans; these preferences varied by sex and BMI.

Seroprevalence of Varicella-Zoster Virus and Measles among Healthcare Workers in a Tertiary Medical Center in Korea.

Measles and varicella still occur in the general population despite the widespread vaccination against them, and healthcare workers (HCWs) are still at risk of exposure to these diseases. Here, we evaluated the seroprevalence of measles and varicella-zoster virus (VZV) in HCWs and the trend of seroprevalence according to age, birth year, and occupational group. The serostatuses of measles and VZV of HCWs during new employee medical examinations between October 2015 and October 2021 were included. Thereafter, the trends of seroprevalence according to age, birth year, and occupational groups were evaluated. Overall, 2070 and 1827 HCWs were evaluated for VZV and measles serostatus, respectively. The seroprevalences of VZV and measles were 91% (1884/2070) and 70% (1284/1827), respectively. Younger HCWs had a significantly lower seroprevalence of measles (p = 0.02, age) and VZV (p = 0.003, birth year and p < 0.001, age). The seroprevalence of measles and VZV was significantly higher among doctors and nursing assistants than among nurses and other HCWs (p < 0.001 in both). In conclusion, the seroprevalence of measles and VZV significantly decreased in younger HCWs. Additionally, monitoring the serostatus of measles and VZV and the immunization of susceptible HCWs are required to prepare and control infectious diseases in healthcare facilities.

Association between Carbohydrate Intake and the Prevalence of Metabolic Syndrome in Korean Women.

Carbohydrates consist of a large proportion of calories in the Asian diet. Therefore, we aimed to investigate the association between carbohydrate intake and metabolic syndrome in Korean women. A cross-sectional analysis was conducted with a total of 4294 Korean women aged 40-69 years from the Korean Genomic and Epidemiology Study (KoGES). Carbohydrate intake was calculated based on a validated food frequency questionnaire. Metabolic syndrome was defined by using the National Cholesterol Education Program, Adult Treatment Panel III (NCEPIII). Logistic regression was used to estimate the association of carbohydrate intake with metabolic syndrome and its components. In this study, high carbohydrate intake seemed to be associated with low socioeconomic status and an imbalanced diet. After adjusting for confounding factors, subjects with higher carbohydrate intake showed an increased risk of metabolic syndrome (odds ratio (OR) 1.34, 95% confidence interval (CI) 1.08-1.66, p-trend = 0.004, highest vs. lowest quartile [≥75.2 vs. <67.0% of energy]), particularly elevated waist circumference. This association was stronger among those with low levels of C-reactive protein (CRP) and those with low dairy intake. In conclusion, higher carbohydrate intake is associated with a higher risk of metabolic syndrome, particularly abdominal obesity, in Korean women. This association may differ according to individuals' CRP level and dairy intake.

Gender disparities in childhood obesity and household food insecurity.

OBJECTIVES: Childhood obesity is a critical health issue. The etiology of childhood obesity is multifactorial, with age, gender, race/ethnicity, and socioeconomic status interacting to affect risk. Food insecurity is known to be associated with risk of childhood obesity, but the body of evidence regarding Koreans is lacking. This study investigated the association between childhood obesity and household food insecurity in Koreans. Other lifestyle and nutritional factors associated with obesity were also examined. METHODS: Using data from the Korean National Health and Nutrition Examination Survey, a cross-sectional study was conducted with 1527 boys and 1366 girls. A comparison of general characteristics and nutritional intake between the groups was made using Student's t tests, χ2 tests, and general linear models. The association between childhood obesity and food insecurity was estimated with logistic regression models, and presented with odds ratios and 95% confidence intervals either with or without covariates. RESULTS: Boys who were obese dined out less frequently and engaged less in regular exercise, but no differences in nutrition intake were observed between children who were and were not obese. Girls who were obese were less likely to have a caregiver and consumed a higher percentage of energy from protein. Boys experiencing household food insecurity were less likely to be obese (adjusted odds ratio, 0.25; 95% confidence interval, 0.06-0.99), but girls with food insecurity were at three times higher risk of obesity (adjusted odds ratio, 3.00; 95% confidence interval, 1.23-7.31). CONCLUSIONS: Differential lifestyle factors are associated with obesity phenotypes in boys and girls. Food insecurity also showed a contrasting association with obesity risk by gender in young Koreans.

Genetic Variations in Thiamin Transferase SLC35F3 and the Risk of Hypertension in Koreans.

Hypertension is a major health issues globally. Multiple genetic and environmental factors are involved in hypertension etiology. Solute carrier family 35 member F3 (SLC35F3) is a type of transporter uptakes thiamin across the cellular and mitochondrial membrane. Recent studies suggested that variations in SLC35F3 are associated with the risk of hypertension; however, studies are limited in Koreans. This study examined the association of the genetic variations in SLC35F3 and the risk of hypertension in Koreans using the Korean Genome Epidemiology Study (Ansan/Ansung study). A total of 8,298 Koreans (males 3,983, females 4,315) were analyzed for their general characteristics, dietary intake, and blood pressure. Twenty-four tagging variations in SLC35F3 were selected and investigated for their association with the risk of hypertension using a sex-stratified approach. Findings suggested that, in males, rs12135117 A allele carriers were at the lower risk for hypertension (adjusted odds ratio, 0.859; 95% confidence interval [CI], 0.740-0.998). In females, rs10910387 TC genotype tended to increase the risk 1.172-fold for hypertension (95% CI, 1.002-1.370). Multiple linear regression models exhibited that rs12135117 A allele was negatively associated with blood pressure in males, and rs10910387 TC genotype had a positive association with blood pressure in females. However, statistical significance for these genetically modified effects was in lacked (Bonferroni's corrected p > 0.002). In conclusion, genetic variation in SLC35F3 is not a decisive prediction marker for hypertension risk in Koreans. Given the rarity of data, more studies are required to evaluate the role of SLC35F3 and thiamin in the hypertension etiology.

A COVID-19 Exposure at a Dental Clinic Where Healthcare Workers Routinely Use Particulate Filtering Respirators.

Asymptomatic/mildly symptomatic coronavirus disease 2019 (COVID-19) patients produce a considerable amount of virus and transmit severe acute respiratory syndrome virus 2 (SARS-CoV-2) through close contact. Preventing in-hospital transmission of SARS-CoV-2 is challenging, since symptom-based screening protocols may miss asymptomatic/mildly symptomatic patients. In particular, dental healthcare workers (HCWs) are at high risk of exposure, as face-to-face contact and exposure to oral secretions is unavoidable. We report exposure of HCWs during dental procedures on a mild symptomatic COVID-19 patient. A 32-year-old male visited a dental clinic at a tertiary care hospital. He experienced mild cough, which started three days before the dental visit, but did not report his symptom during the entrance screening. He underwent several dental procedures and imaging for orthognathic surgery without wearing a mask. Seven HCWs were closely exposed to the patient during dental procedures that could have generated droplets and aerosols. One HCW had close contact with the patient during radiologic exams, and seven HCWs had casual contact. All HCWs wore particulate filtering respirators with 94% filter capacity and gloves, but none wore eye protection or gowns. The next day, the patient experienced dysgeusia and was diagnosed with COVID-19 with high viral load. All HCWs who had close contact with the patient were quarantined for 14 days, and polymerase chain reaction and antibody tests for SARS-CoV-2 were negative. This exposure event suggests the protective effect of particulate filtering respirators in dental clinics. The recommendations of different levels of personal protective equipment (PPE) for dental HCWs according to the procedure types should be established according to the planned procedure, the risk of COVID-19 infection of the patient, and the outbreak situation of the community.

Minimizing contamination in the use of personal protective equipment: Simulation results through tracking contamination and enhanced protocols.

BACKGROUND: Due to variations and the inadequate use of personal protective equipment (PPE), this study aimed to evaluate our enhanced PPE protocols for minimizing doffing contamination. METHODS: Among 3 PPE kits (simple, Level D, and Level C), 30 participants conducted the first simulation in their adapted way and the second following enhanced protocols. After donning, participants performed a 1-minute simulation of direct care on a patient simulator covered with fluorescent powder. For tracking contamination routes between doffing processes, fluorescent powder contamination was examined with ultraviolet lamps in the darkened room. RESULTS: Participants were mostly registered nurses (N = 27, 90%), female (87%), and on average 31.7 years old with 8.5 years of clinical experience. Among 61 total simulations, 32 had at least 1 contamination (52.5%); "Noticeable" level (40%) at the "hands-fingers" and "shirt" body areas were most frequent. For first and second simulations with identical PPE kits, compared to the first with adapted practice, the second with enhanced protocols showed a significant reduction in doffing contamination rates (72.7% vs 22.7%, P = .0009 for both Level C and D; 77.8% vs 27.8%, P = .0027 for Level D). CONCLUSIONS: Our enhanced protocols could significantly reduce contaminations. More studies are necessary to provide safer PPE protocol options.

The Association between Dietary Vitamin A and C Intakes and Cataract: Data from Korea National Health and Nutrition Examination Survey 2012.

Oxidative stress in eye lens is one of the main causes of the cataract. Dietary antioxidants including vitamin A and C are therefore known to be associated with the risk of the disease. However, evidences are still lacking in Koreans. This study aimed to examine whether dietary vitamin A and C levels are associated with the cataract, using data of Korea National Health and Nutrition Examination Survey 2012. A total of 3,344 individuals (599 cases and 2,745 controls) were analyzed in the study. Dietary data was classified into 3 groups following Dietary Reference Intakes for Koreans 2015: 1) ≤ estimated average requirements (EAR), 2) EAR-recommended nutrient intake (RNI), and 3) ≥ RNI. Findings suggested normal subjects (controls) had better vitamin A and C nutritional status. Vitamin A and C intakes of normal subjects were significantly higher than those of cataract cases (p < 0.001, respectively). Ratio of subjects who consumed vitamin A and C lower than EAR was higher in cataract cases compared to normal subjects (p < 0.001, respectively). These antioxidant intake levels predicted that having lower level of vitamins lower than EAR increased the odd ratios (ORs) for cataract [for vitamin A: OR, 1.89; 95% confidence interval (CI), 1.55-2.31 and for vitamin C: OR, 2.06; 95% CI, 1.69-2.51]. However, such associations were not retained, when the subjects' demographic and lifestyle factor were adjusted. In conclusion, vitamin A and C showed a protective effect against cataract. However, subjects' life style and demographic factors nullified the association. More studies are required to verify the true association between dietary antioxidants and risk of cataract in Koreans.