Inhalation exposure to nanosized aerosols of disinfectants for the application of continuous releasing sprayers and fogger.

This study aimed to investigate the airborne exposure to aerosols according to the particle size distribution of three different spray types (nano-nozzled spray gun, low-temperature steam spray, and fogger) and compare the concentrations of inhaled aerosols between children and adults. Airborne aerosols released from three products were observed using size-segregated particle measurements, and particle concentrations deposited in the respiratory tracts of adults and children were estimated using multi-path particle dosimetry lung deposition models. All types of sprayers generated the most nanoparticles (~100 nm). Due to their higher respiratory rate than adults, a larger number of particles <1.0 µm deposited in the children's respiratory tracts was higher. The sequences of the total number of particles in the respiratory regions after spraying nano-nozzled spray gun and fogger were alveolar (AL)>tracheobronchial (TB)>head airway (HA) in adults and AL>HA>TB in children. Meanwhile, the trend of low-temperature steam spray was AL>TB>HA in adults and AL>TB>HA in children.

Study on the daily Ad Libitum smoking habits of active Korean smokers and their effect on urinary smoking exposure and impact biomarkers.

INTRODUCTION: Understanding interactions of smoking topography with biomarkers of exposure to tobacco is essential for accurate smoking risk assessments. METHODS: In this study, the smoking topography and the levels of tobacco smoke exposure urinary biomarkers of a sample of active Korean smokers were quantified and measured. The results were used to investigate the effect of daily activities and smoking time on the smoking topography. Moreover, correlations between the smoking topography parameters and biomarkers were assessed. RESULTS: No significant effect of either the daily activities or time on the smoking topography of the subjects were observed. Synchronic correlations of the cigarette consumption per day (CPD) and the average flow per puff with both urinary cotinine and trans-3'-hydroxycotinine were significant. For the urinary nicotine metabolites, the peak levels appeared when the CPD was over 19 cigarettes per day and the average puff velocity was between 35 and 45 ml/s. Nevertheless, when the average flow was over 60 ml/s, the levels of cotinine and trans-3'-hydroxycotinine significantly dropped. CONCLUSIONS: The findings of this study may be beneficial for further smoking risk assessments with contributions of both the smoking topography and biomarkers to provide current smokers with applicable cession programs.Clinical significanceSmoking habits and levels of urinary biomarkers of Korean smokers are investigated.People with a higher dependency on nicotine smoke cigarettes with slower puffs.Effects of daily activities or time on smoking topography were not significant.Correlations between smoking topography and urinary biomarkers were significant.Peak biomarker levels were observed under certain smoking topography conditions.

Controlling Graphene Wrinkles through the Phase Transition of a Polymer with a Low Critical Solution Temperature.

A novel method for controlling reduced graphene oxide (rGO) wrinkles through a phase transition in a solution using a low critical solution temperature (LCST) polymer dispersant has been developed. The polymer dispersant is designed by control of architecture and composition using reversible addition-fragmentation chain transfer polymerization. Synthesized poly(2-(dimethylaminoethyl) methacrylate-block-styrene) (PDbS) can be successfully functionalized on the rGO surface via noncovalent functionalization. PDbS-functionalized rGO (PDbS-rGO) exhibits good dispersibility in an aqueous phase at room temperature and forms wrinkles on the PDbS-rGO surface because of phase transition at the LCST of the polymer dispersant. The formation of PDbS-rGO wrinkles is controlled by varying the aggregation number of the polymer dispersant on the PDbS-rGO surface that strongly depends on temperature. This is confirmed by transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy (ID' /IG ratios are 0.560, 0.579, and 0.684, which correspond to 45, 70, and 95 °C, respectively). In addition, the mechanism of wrinkle control is proved by gold nanoparticles that are grown in polymer dispersant on the PDbS-rGO surface.

Korean male active smokers: quantifying their smoking habits and the transformation factor among biomarkers in urine and blood.

OBJECTIVES: The aim of the study was to investigate the correlations within the levels of biomarkers in different biological matrices, along with smoking topography variables, among active male smokers in Korea. Accordingly, we defined a transformation factor to convert level of tobacco smoke exposure and impact biomarkers from different biometrics. METHODS: We examined smoking topography of recruited volunteers using a self-reporting survey. The level of tobacco smoke exposure and impact biomarkers in subjects' urine and blood were analysed. Results were used to assess the correlations between the topography survey items with biomarkers in biological matrices. The relationship between the biomarkers in urine and blood was analysed. Accordingly, we defined a transformation factor as the ratio of different biomarkers in urine and blood matrices. RESULTS: Significant correlations among smoking topography variables and biomarkers were found. Besides, a strong significant association was found among urine and blood cotinine (ρ = 0.817) and NMR (ρ = 0.905). Urine vs blood cotinine and NMR transformation factors were calculated to be 6.17 L-Blood/g-Creatinine and 10.2, respectively. CONCLUSIONS: The validated transformation factor connects epidemiological cohort studies with tobacco smoking exposure risk assessment. Hence, this study might be beneficial for further habit-based smoking risk assessments to obtain successful regional cession policies.

Impact of COVID-19 Pandemic on the National PPM Tuberculosis Control Project in Korea: the Korean PPM Monitoring Database between July 2019 and June 2020.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic caused disruptions to healthcare systems and endangered the control and prevention of tuberculosis (TB). We investigated the nationwide effects of COVID-19 on the national Public-Private Mix (PPM) TB control project in Korea, using monitoring indicators from the Korean PPM monitoring database. METHODS: The Korean PPM monitoring database includes data from patients registered at PPM hospitals throughout the country. Data of six monitoring indicators for active TB cases updated between July 2019 and June 2020 were collected. The data of each cohort throughout the country and in Daegu-Gyeongbuk, Seoul Metropolitan Area, and Jeonnam-Jeonbuk were collated to provide nationwide data. The data were compared using the χ² test for trend to evaluate quarterly trends of each monitoring indicator at the national level and in the prespecified regions. RESULTS: Test coverages of sputum smear (P = 0.622) and culture (P = 0.815), drug susceptibility test (P = 0.750), and adherence rate to initial standard treatment (P = 0.901) at the national level were not significantly different during the study period. The rate of loss to follow-up among TB cases at the national level was not significantly different (P = 0.088); however, the treatment success rate among the smear-positive drug-susceptible pulmonary TB cohort at the national level significantly decreased, from 90.6% to 84.1% (P < 0.001). Treatment success rate in the Seoul metropolitan area also significantly decreased during the study period, from 89.4% to 84.5% (P = 0.006). CONCLUSION: Our study showed that initial TB management during the COVID-19 pandemic was properly administered under the PPM project in Korea. However, our study cannot confirm or conclude a decreased treatment success rate after the COVID-19 pandemic due to limited data.

Chronic Kidney Disease Induces Inflammatory CD40+ Monocyte Differentiation via Homocysteine Elevation and DNA Hypomethylation.

RATIONALE: Patients with chronic kidney disease (CKD) develop hyperhomocysteinemia and have a higher cardiovascular mortality than those without hyperhomocysteinemia by 10-fold. OBJECTIVE: We investigated monocyte differentiation in human CKD and cardiovascular disease (CVD). METHODS AND RESULTS: We identified CD40 as a CKD-related monocyte activation gene using CKD-monocyte -mRNA array analysis and classified CD40 monocyte (CD40+CD14+) as a stronger inflammatory subset than the intermediate monocyte (CD14++CD16+) subset. We recruited 27 patients with CVD/CKD and 14 healthy subjects and found that CD40/CD40 classical/CD40 intermediate monocyte (CD40+CD14+/CD40+CD14++CD16-/CD40+CD14++CD16+), plasma homocysteine, S-adenosylhomocysteine, and S-adenosylmethionine levels were higher in CVD and further elevated in CVD+CKD. CD40 and CD40 intermediate subsets were positively correlated with plasma/cellular homocysteine levels, S-adenosylhomocysteine and S-adenosylmethionine but negatively correlated with estimated glomerular filtration rate. Hyperhomocysteinemia was established as a likely mediator for CKD-induced CD40 intermediate monocyte, and reduced S-adenosylhomocysteine/S-adenosylmethionine was established for CKD-induced CD40/CD40 intermediate monocyte. Soluble CD40 ligand, tumor necrosis factor (TNF)-α/interleukin (IL)-6/interferon (IFN)-γ levels were elevated in CVD/CKD. CKD serum/homocysteine/CD40L/increased TNF-α/IL-6/IFN-γ-induced CD40/CD40 intermediate monocyte in peripheral blood monocyte. Homocysteine and CKD serum-induced CD40 monocyte were prevented by neutralizing antibodies against CD40L/TNF-α/IL-6. DNA hypomethylation was found on nuclear factor-κB consensus element in CD40 promoter in white blood cells from patients with CKD with lower S-adenosylmethionine / S-adenosylhomocysteine ratios. Finally, homocysteine inhibited DNA methyltransferase-1 activity and promoted CD40 intermediate monocyte differentiation, which was reversed by folic acid in peripheral blood monocyte. CONCLUSIONS: CD40 monocyte is a novel inflammatory monocyte subset that appears to be a biomarker for CKD severity. Hyperhomocysteinemia mediates CD40 monocyte differentiation via soluble CD40 ligand induction and CD40 DNA hypomethylation in CKD.

Osteopontin Levels in Human Milk Vary Across Countries and Within Lactation Period: Data From a Multicenter Study.

OBJECTIVES: Osteopontin (OPN) is a multifunctional protein expressed in many cell types, tissues and body fluids with the highest concentrations found in milk; significantly higher in human than in bovine milk. Intervention studies have indicated beneficial effects of supplementing infant formula with bovine OPN. In this multicenter study, we determined the OPN content in human milk samples from 629 Chinese, Danish, Japanese and Korean mothers. METHODS: At each study site, milk samples were collected and analyzed for OPN and protein concentration using ELISA and infrared spectroscopy, respectively. RESULTS: A total of 829 milk samples from 629 women were included. When delivering the first sample, mean maternal age was 31.4 years (SD 4.0), and median infant age was 13.4 weeks (interquartile range 4.6-17.9). The median OPN concentration varied across sites; from 99.7 mg/L in Danish, 185.0 mg/L in Japanese, 216.2 mg/L in Korean to 266.2 mg/L in Chinese mothers (P < 0.001), corresponding to 1.3%, 2.4%, 1.8% and 2.7% of the total protein content (OPN/protein%) (P < 0.05), respectively. Based on 75 Chinese and 33 Japanese mothers delivering more than 1 sample, multilevel (mixed model) linear regression analysis showed a decrease in OPN concentration with infant age (ß = (-11.3), 95% confidence interval (CI) = (-13.9) to (-8.8) and ß = (-2.1), 95% CI = (-3.2) to (-0.9), respectively). CONCLUSIONS: In this large multicenter study, we observed statistically significant differences in the OPN concentration and the OPN/protein% in human milk samples between countries. Based on mothers delivering more than 1 sample, a significant decrease within the lactation period was observed.

Decreased blood pressure associated with in-vehicle exposure to carbon monoxide in Korean volunteers.

BACKGROUND: Carbon monoxide (CO) is one of the primary components of emissions from light-duty vehicles, and reportedly comprises 77% of all pollutants emitted in terms of concentration. Exposure to CO aggravates cardiovascular disease and causes other health disorders. The study was aimed to assess the negative effects by injecting different amounts of CO concentration directly to human volunteers boarding in the car. METHODS: Human volunteers were exposed to CO concentrations of 0, 33.2, and 72.4 ppm, respectively during the first test and 0, 30.3, and 48.8 ppm respectively during the second test while seated in the car. The volunteers were exposed to each concentration for approximately 45 min. After exposure, blood pressure measurement, blood collection (carboxyhemoglobin [COHb] analysis), medical interview, echocardiography test, and cognitive reaction test were performed. RESULT: In patients who were exposed to a mean concentration of CO for 72.4 ± 1.4 ppm during the first exposure test and 48.8 ± 3.7 ppm during the second exposure test, the COHb level exceeded 2%. Moreover, the diastolic blood pressure was decreased while increasing in CO concentration after exposure. The medical interview findings showed that the degree of fatigue was increased and the degree of concentration was reduced when the exposed concentration of CO was increased. CONCLUSION: Although the study had a limited sample size, we found that even a low concentration of CO flowing into a car could have a negative influence on human health, such as change of blood pressure and degree of fatigue.

Human exposure and risk assessment of cadmium for residents of abandoned metal mine areas in Korea.

The objective of this study is to find the Cd levels in agricultural crops compared to soil, to evaluate the relationship between daily intake dose through the multimedia/multi-pathway of human exposure and biomarker levels of the residents in mine vicinity area. We collected and cited the data of four out of ten health impact assessments for the residents of abandoned mine areas undertaken by the Korea Ministry of Environment in 2008. The Cd levels in soil were significantly decreased by the separation distance from the mines. The Cd levels in blood were significantly different between residents in mine areas and in comparative areas, but urinary Cd levels did not differ. The Cd levels in blood were related to the age; the separation distance from mine to residence; the daily intake dose via ingestion of drinking water, crops, and surface soil; and inhalation of ambient air of Cd, but urinary Cd levels were not relevant with various sociodemographic characteristics and exposure factors. The average hazard quotient (HQ) value of Cd in the mining site was below 1.0, but the maximum HQ was closed to 1.0. The results indicated that the ingestion of Cd-contaminated soil and agricultural crops by local inhabitants could pose potential adverse health effects to long-term residents consuming rice grown near to the mining areas.

Antimicrobial activities of active component isolated from Lawsonia inermis leaves and structure-activity relationships of its analogues against food-borne bacteria.

The antimicrobial activities of Lawsonia inermis leaf extract and 2-hydroxy-1,4-naphthoquinone analogues against food-borne bacteria. The antimicrobial activities of five fractions derived from the methanol extract of Lawsonia inermis leaves were evaluated against 7 food-borne bacteria. 2-Hydroxy-1,4-naphthoquinone was isolated by chromatographic analyses. 2-Hydroxy-1,4-naphthoquinone showed the strong activities against Bacillus cereus, Listeria monocytogenes, Salmonella enterica, Shigella sonnei, Staphylococcus epidermidis, and S. intermedius, but exerted no growth-inhibitory activities against S. typhimurium. The antimicrobial activities of the 2-hydroxy-1,4-naphthoquinone analogues were tested against 7 food-borne bacteria to establish structure-activity relationships. Hydroxyl (2-hydroxy-1,4-naphthoquinone and 5-hydroxy-1,4-naphthoquinone), methoxy (2-methoxy-1,4-naphthoquinone), and methyl (2-methyl-1,4-naphthoquinone, and 5-hydroxy-2-methyl-1,4-naphthoquinone) functional groups on the 1,4-naphthoquinone skeleton possessed potent activities, whereas bromo (2-bromo-1,4-naphthoquinone and 2,3-dibromo-1,4-naphthoquione) and chloro (2,3-dichloro-1,4-naphthoquinone) exhibited no activity against 7 food-borne bacteria. The L. inermis leaf extract and 2-hydroxy-1,4-naphthoquinone analogues should be useful as natural antimicrobial agents against food-borne bacteria.

How to get the most from microarray data: advice from reverse genomics.

BACKGROUND: Whole-genome profiling of gene expression is a powerful tool for identifying cancer-associated genes. Genes differentially expressed between normal and tumorous tissues are usually considered to be cancer associated. We recently demonstrated that the analysis of interindividual variation in gene expression can be useful for identifying cancer associated genes. The goal of this study was to identify the best microarray data-derived predictor of known cancer associated genes. RESULTS: We found that the traditional approach of identifying cancer genes--identifying differentially expressed genes--is not very efficient. The analysis of interindividual variation of gene expression in tumor samples identifies cancer-associated genes more effectively. The results were consistent across 4 major types of cancer: breast, colorectal, lung, and prostate. We used recently reported cancer-associated genes (2011-2012) for validation and found that novel cancer-associated genes can be best identified by elevated variance of the gene expression in tumor samples. CONCLUSIONS: The observation that the high interindividual variation of gene expression in tumor tissues is the best predictor of cancer-associated genes is likely a result of tumor heterogeneity on gene level. Computer simulation demonstrates that in the case of heterogeneity, an assessment of variance in tumors provides a better identification of cancer genes than does the comparison of the expression in normal and tumor tissues. Our results thus challenge the current paradigm that comparing the mean expression between normal and tumorous tissues is the best approach to identifying cancer-associated genes; we found that the high interindividual variation in expression is a better approach, and that using variation would improve our chances of identifying cancer-associated genes.

Acaricidal activities against house dust mites of spearmint oil and its constituents.

The aim of this study was to evaluate the acaricidal activities of spearmint oil and carvone derivatives against house dust mites using contact and fumigant toxicity bioassays to replace benzyl benzoate as a synthetic acaricide. Based on the LD50 values, the contact toxicity bioassay revealed that dihydrocarvone (0.95 and 0.88 µg/cm2) was 7.7 and 6.8 times more toxic than benzyl benzoate (7.33 and 6.01 µg/cm2) against Dermatophagoides farinae and Dermatophagoides pteronyssinus, respectively, followed by carvone (3.78 and 3.23 µg/cm2), spearmint oil (5.16 and 4.64 µg/cm2), carveol (6.00 and 5.80 µg/cm2), and dihydrocarveol (8.23 and 7.10 µg/cm2). Results of the fumigant toxicity bioassay showed that dihydrocarvone (2.73 and 2.16 µg/cm2) was approximately 4.0 and 4.8 times more effective than benzyl benzoate (11.00 and 10.27 µg/cm2), followed by carvone (6.63 and 5.78 µg/cm2), carveol (7.58 and 7.24 µg/cm2), spearmint oil (9.55 and 8.10 µg/cm2), and dihydrocarveol (9.79 and 8.14 µg/cm2). Taken together, spearmint oil and carvone derivatives are a likely viable alternative to synthetic acaricides for managing house dust mites.

Antimicrobial potentials of active component isolated from Citrullus colocynthis fruits and structure-activity relationships of its analogues against foodborne bacteria.

BACKGROUND: Synthetic preservatives have been consistently used to maintain the quality of food products. However, the degree of danger to human health cannot be ignored. In this study, the antimicrobial activities of Citrullus colocynthis fruits and 4-methylquinoline analogues were investigated to develop natural preservatives against foodborne bacteria. RESULTS: Antimicrobial activities of the methanol extract and five fractions derived from C. colocynthis fruits were evaluated against five foodborne bacteria. The chloroform fraction possessed strong activities against five foodborne bacteria. 4-Methylquinoline was isolated by chromatographic analyses. To establish the structure-activity relationships, the antimicrobial activities of 4-methylquinoline analogues (2-hydroxyquinoline, 4-hydroxyquinoline, 6-hydroxyquinoline, 2-methylquinoline, 6-methyquinoline, 8-methylquinoline and 2-methyl-8-hydroxyquinoline) were tested against food-borne bacteria. When employing the agar diffusion method, 2-methyl-8-hydroxyquinoline was found to have potent activities against the five foodborne bacteria. In terms of minimum bactericidal concentration or minimum inhibitory concentration, 2-methyl-8-hydroxyquinoline had significantly higher antimicrobial activity against the five foodborne bacteria. CONCLUSION: Citrullus colocynthis fruits and 4-methylquinoline analogues could be useful for the development of eco-friendly food supplemental agents and pharmaceuticals.

Health risk assessment of uranium intake from private residential drinking groundwater facilities based on geological characteristics across the Republic of Korea.

Groundwater contributes to an average of 8 % of the total water source capacity in the Republic of Korea. Hence, private residential households in rural areas in Korea are still using groundwater for drinking without any regular water quality inspection. This can increase the risk of exposure to natural radionuclides like uranium through drinking groundwater. This study investigated the uranium level in drinking groundwater all over the country by analyzing 11,451 samples from private residential drinking groundwater facilities and compared the exposure amount and its associated carcinogenic and non-carcinogenic risk based on the geological characteristics of the aquifer. Results yield that although the average hazard quotient (HQ) and excess cancer risk (ECR) of exposure to natural uranium through drinking groundwater were respectively below 1 and 1 × 10-6 and do not indicate a potential health hazard, significantly high HQ and ECR up to respectively 70 and 4 × 10-4 in samples where the aquifer is the Jurassic granite observed. Accordingly, regular water quality investigation and onsite treatment methods are required to provide healthy drinking water in such areas.

Early Postoperative Benefits in Receptive and Expressive Language Development After Cochlear Implantation Under 9 Months of Age in Comparison to Implantation at Later Ages.

OBJECTIVES: The recent expansion of eligibility for cochlear implantation (CI) by the U.S. Food and Drug Administration (FDA) to include infants as young as 9 months has reignited debates concerning the clinically appropriate cut-off age for pediatric CI. Our study compared the early postoperative trajectories of receptive and expressive language development in children who received CI before 9 months of age with those who received it between 9 and 12 months. This study involved a unique pediatric cohort with documented etiology, where the timing of CI was based on objective criteria and efforts were made to minimize the influence of parental socioeconomic status. METHODS: A retrospective review of 98 pediatric implantees recruited at a tertiary referral center was conducted. The timing of CI was based on auditory and language criteria focused on the extent of delay corresponding to the bottom 1st percentile of language development among age-matched controls, with patients categorized into very early (CI at <9 months), early (CI at 9-12 months) and delayed (CI at 12-18 months) CI groups. Postoperative receptive/expressive language development was assessed using the Sequenced Language Scale for Infants receptive and expressive standardized scores and percentiles. RESULTS: Only the very early CI group showed significant improvements in receptive language starting at 3 months post-CI, aligning with normal-hearing peers by 9 months and maintaining this level until age 2 years. During this period (<2 years), all improvements were more pronounced in receptive language than in expressive language. CONCLUSION: CI before 9 months of age significantly improved receptive language development compared to later CI, with improvements sustained at least up to the age of 2. This study supports the consideration of earlier CI, beyond pediatric Food and Drug Administration labeling criteria (>9 months), in children with profound deafness who have a clear deafness etiology and language development delays (<1st percentile).

Timely Pulmonary Tuberculosis Diagnosis Based on the Epidemiological Disease Spectrum: Population-Based Prospective Cohort Study in the Republic of Korea.

BACKGROUND: Timely pulmonary tuberculosis (PTB) diagnosis is a global health priority for interrupting transmission and optimizing treatment outcomes. The traditional dichotomous time-divided approach for addressing time delays in diagnosis has limited clinical application because the time delay significantly varies depending on each community in question. OBJECTIVE: We aimed to reevaluate the diagnosis time delay based on the PTB disease spectrum using a novel scoring system that was applied at the national level in the Republic of Korea. METHODS: The Pulmonary Tuberculosis Spectrum Score (PTBSS) was developed based on previously published proposals related to the disease spectrum, and its validity was assessed by examining both all-cause and PTB-related mortality. In our analysis, we integrated the PTBSS into the Korea Tuberculosis Cohort Registry. We evaluated various time delays, including patient, health care, and overall delays, and their system-associated variables in line with each PTBSS. Furthermore, we reclassified the scores into distinct categories of mild (PTBSS=0-1), moderate (PBTBSS=2-3), and severe (PBTBSS=4-6) using a multivariate regression approach. RESULTS: Among the 14,031 Korean patients with active PTB whose data were analyzed from 2018 to 2020, 37% (n=5191), 38% (n=5328), and 25% (n=3512) were classified as having a mild, moderate, and severe disease status, respectively, according to the PTBSS. This classification can therefore reflect the disease spectrum of PTB by considering the correlation of the score with mortality. The time delay patterns differed according to the PTBSS. In health care delays according to the PTBSS, greater PTB disease progression was associated with a shorter diagnosis period, since the condition is microbiologically easy to diagnose. However, with respect to patient delays, the change in elapsed time showed a U-shaped pattern as PTB progressed. This means that a remarkable patient delay in the real-world setting might occur at both apical ends of the spectrum (ie, in both mild and severe cases of PTB). Independent risk factors for a severe PTB pattern were age (adjusted odds ratio 1.014) and male sex (adjusted odds ratio 1.422), whereas no significant risk factor was found for mild PTB. CONCLUSIONS: Timely PTB diagnosis should be accomplished. This can be improved with use of the PTBSS, a simple and intuitive scoring system, which can be more helpful in clinical and public health applications compared to the traditional dichotomous time-only approach.

Acaricidal toxicities of 1-hydroxynaphthalene from Scutellaria barbata and its derivatives against house dust and storage mites.

The essential oil of Scutellaria barbata was extracted using a steam distillation and then evaluated via fumigant and contact toxicity bioassays against Dermatophagoides farinae, Dermatophagoides pteronyssinus, and Tyrophagus putrescentiae. The acaricidal toxicities of 1-hydroxynaphthalene from S. barbata oil and its derivatives were determined and compared with those of benzyl benzoate. Based on the LD50 values of 1-hydroxynaphthalene derivatives against D. farinae, D. pteronyssinus, and T. putrescentiae, obtained using a fumigant toxicity bioassay, the acaricidal activity of 1-hydroxynaphthalene (2.11, 2.37, and 4.50 µg/cm2) was 4.76, 6.00, and 2.68 times higher than that of benzyl benzoate (10.05, 9.50, and 12.50 µg/cm2) in the corresponding order, which was followed by that of 2-hydroxynaphthalene (9.50, 9.00, and 11.50 µg/cm2). On the contact toxicity bioassay, the acaricidal activity of 1-hydroxynaphthalene (0.79, 0.92, and 2.50 µg/cm2) was 9.49, 6.52, and 3.76 times higher than that of benzyl benzoate (7.50, 6.00, and 9.41 µg/cm2), which was followed by that of 2-hydroxynaphthalene (4.21, 4.80, and 6.50 µg/cm2). In conclusion, our results indicate that S. barbata oil and 1-hydroxynaphthalene derivatives might be effective natural agents for the management of house dust and storage mites.

B cell receptor-induced IL-10 production from neonatal mouse CD19+CD43- cells depends on STAT5-mediated IL-6 secretion.

Newborns are unable to reach the adult-level humoral immune response partly due to the potent immunoregulatory role of IL-10. Increased IL-10 production by neonatal B cells has been attributed to the larger population of IL-10-producting CD43+ B-1 cells in neonates. Here, we show that neonatal mouse CD43- non-B-1 cells also produce substantial amounts of IL-10 following B cell antigen receptor (BCR) activation. In neonatal mouse CD43- non-B-1 cells, BCR engagement activated STAT5 under the control of phosphorylated forms of signaling molecules Syk, Btk, PKC, FAK, and Rac1. Neonatal STAT5 activation led to IL-6 production, which in turn was responsible for IL-10 production in an autocrine/paracrine fashion through the activation of STAT3. In addition to the increased IL-6 production in response to BCR stimulation, elevated expression of IL-6Rα expression in neonatal B cells rendered them highly susceptible to IL-6-mediated STAT3 phosphorylation and IL-10 production. Finally, IL-10 secreted from neonatal mouse CD43- non-B-1 cells was sufficient to inhibit TNF-α secretion by macrophages. Our results unveil a distinct mechanism of IL-6-dependent IL-10 production in BCR-stimulated neonatal CD19+CD43- B cells.

Dietary exposure and risk assessment of polybrominated diphenyl ethers in the Republic of Korea: A nationwide study.

In this study, the dietary exposure to seven polybrominated diphenyl ethers (PBDEs) congener groups, including 22 types of PBDEs compounds, through consumption of 80 food items in Korean diets along with their risk assessment has been investigated. To process this, the concentrations of the target PBDEs in samples of food items were measured. The consumption amounts of the target food items were derived from the results of the 24 h food recall interview of subjects who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) from 2015 to 2019. Thereafter, the estimated daily intake and risk of exposure for each PBDEs congener group were assessed. Results indicate that although exposure to the target PBDEs was not significant enough to cause a potential health risk, deca-BDE (BDE-209) was the dominant congener in terms of both exposure and risk for consumers in all age groups. Furthermore, while eating seafood was the dominant path for dietary exposure to PBDEs, exposure to octa-BDEs was mostly through livestock products. Accordingly, to protect all consumers, especially those aged below 2 years and over 65 years, more accurate food quality management is required for controlling the dietary intake of PBDEs.

Preparation of Hypoallergenic Whey Protein Hydrolysate by a Mixture of Alcalase and Prozyme and Evaluation of Its Digestibility and Immunoregulatory Properties.

Whey protein (WP) has nutritional value, but the presence of ß-lactoglobulin (ß-LG) and α-lactalbumin (α-LA) cause allergic reactions. In this study, hypoallergenic whey protein hydrolyate (HWPH) was prepared by decomposing ß-LG and α-LA of WP using exo- and endo-type proteases. The enzyme mixing ratio and reaction conditions were optimized using response surface methodology (RSM). Degradation of α-LA and ß-LG was confirmed through gel electrophoresis, and digestion, and absorption rate, and immunostimulatory response were measured using in vitro and in vivo systems. Through RSM analysis, the optimal hydrolysis conditions for degradation of α-LA and ß-LG included a 1:1 mixture of Alcalase and Prozyme reacted for 10 h at a 1.0% enzyme concentration relative to substrate. The molecular weight of HWPH was <5 kDa, and leucine was the prominent free amino acid. Both in vitro and in vivo tests showed that digestibility and intestinal permeability were higher in HWPH than in WP. In BALB/c mice, as compared to WP, HWPH reduced allergic reactions by inducing elevated Type 1/Type 2 helper T cell ratio in the blood, splenocytes, and small intestine. Thus, HWPH may be utilized in a variety of low allergenicity products intended for infants, adults, and the elderly.