• IMMUNE NETWORK
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• v.21 no.6
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• pp.39.1-39.18
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• 2021

The high virulent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus that emerged in China at the end of 2019 has generated novel coronavirus disease, coronavirus disease 2019 (COVID-19), causing a pandemic worldwide. Every country has made great efforts to struggle against SARS-CoV-2 infection, including massive vaccination, immunological patients' surveillance, and the utilization of convalescence plasma for COVID-19 therapy. These efforts are associated with the attempts to increase the titers of SARS-CoV-2 neutralizing Abs (nAbs) generated either after infection or vaccination that represent the body's immune status. As there is no standard therapy for COVID-19 yet, virus eradication will mainly depend on these nAbs contents in the body. Therefore, serological nAbs neutralization assays become a requirement for researchers and clinicians to measure nAbs titers. Different platforms have been developed to evaluate nAbs titers utilizing various epitopes sources, including neutralization assays based on the live virus, pseudovirus, and neutralization assays utilizing recombinant SARS-CoV-2 S glycoprotein receptor binding site, receptor-binding domain. As a standard neutralization assay, the plaque reduction neutralization test (PRNT) requires isolation and propagation of live pathogenic SARS-CoV-2 virus conducted in a BSL-3 containment. Hence, other surrogate neutralization assays relevant to the PRNT play important alternatives that offer better safety besides facilitating high throughput analyses. This review discusses the current neutralization assay platforms used to evaluate nAbs, their techniques, advantages, and limitations.

• Journal of Preventive Medicine and Public Health
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• v.57 no.3
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• pp.252-259
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• 2024

Objectives: This study investigated factors associated with the retention of people living with human immunodeficiency virus (HIV) on antiretroviral therapy (ART) during the first 3 years of treatment. Methods: A retrospective study using electronic health records was conducted at a tertiary hospital in Jakarta, Indonesia. Adult HIV-positive patients who started ART from 2010 until 2020 were included. A binary logistic regression model was used to identify factors associated with ART retention in the first 3 years. Results: In total, 535 respondents were included in the analysis. The ART retention rates for the first, second, and third years were 83.7%, 79.1%, and 77.2%, respectively. The multivariate analysis revealed a negative association between CD4 count when starting ART and retention. Patients with CD4 counts >200 cells/mL were 0.65 times less likely to have good retention than those with CD4 counts ≤200 cells/mL. The year of starting ART was also significantly associated with retention. Patients who started ART in 2010-2013 or 2014-2016 were less likely to have good retention than those who started ART in 2017-2020, with adjusted odds ratios of 0.52 and 0.40, respectively. Patients who received efavirenz-based therapy were 1.69 times more likely to have good retention than those who received nevirapine (95% confidence interval, 1.05 to 2.72). Conclusions: Our study revealed a decline in ART retention in the third year. The CD4 count, year of enrollment, and an efavirenz-based regimen were significantly associated with retention. Patient engagement has long been a priority in HIV programs, with interventions being implemented to address this issue.

• Safety and Health at Work
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• v.15 no.2
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• pp.187-191
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• 2024

Background: Effective near-miss management is important in preventing workplace accidents. A company's inadequate response to near-miss reports can lead workers to feel insecure and dissatisfied with the company. We investigated the relationship between companies' responses to near-miss reports and turnover intentions of workers. Methods: We conducted a cross-sectional study using online self-administered questionnaire survey to workers aged ≥20 years in Japan in March 2022. The analysis included 5,071 participants who had nearmiss experiences and reported them to their companies. The independent variable was companies' responses to near-miss reports, classified into three categories: adequate response group, inadequate response group, and no response group. The dependent variable was turnover intentions. We calculated the odds ratio and 95% confidential interval (CI) using multilevel logistic regression analyses nested for industries and adjusted for covariates. Results: Of the 5,071 participants, 3,058 (60.3%) were adequate response group, 1,484 (29.3%) were inadequate response group, and 529 (10.4%) were no response group. In multivariable adjusted model, compared with adequate response group, the odds ratio of inadequate response group and no response group were 1.80 (95% CI: 1.56-2.08) and 2.63 (95% CI: 2.15-3.22), respectively. Conclusion: Our results suggested that there was a relationship between companies' responses to the near-miss reports and turnover intentions of workers. It is important not only to collect near-misses but also to respond appropriately to the reports and provide feedback to workers.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.478-489
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• 2010

Penthiopyrad is a fungicide agent in types of pyrazole which is showing the effect of prevention in fungal disease and powdery mildew. In order to register this new pesticide, reports of acute toxicity and chronic toxicity by animal study were examined to set acceptable daily intake to evaluate hazards of consumers. Acute toxicity was low in toxic, and it did not have the effect of acute dermal toxicity, acute eye irritation, or skin sensitization. As the result of the study in chronic toxicity, the common effect of chemical appeared in the liver and thyroid which was proven as a toxic effect. Two-generation reproduction toxicity, genotoxicity, and prenatal development toxicity were not proven. As the result of carcinogenic study, increase of thyiroid follicular adenoma in the rat and the frequency of liver hepatocellar adenoma in mice were also increased. However, it was decided that the threshold value on the effect in chemicals could be controlled through study liver enzyme induction. Therefore, the ADI for penthiopyrad is 0.081 mg/kg/ bw/day, based on the NOAEL of 8.10 mg/kg bw/day of twelve-months dogs study and applying an uncertainty factor of 100.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.109-120
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• 2012

This study was conducted to monitor 284 pesticides residue level in 2,914 commercial agricultural products in the northern area of Seoul in 2011 by the multi class pesticide multiresidue analysis methods in Korea Food Code using GC, HPLC, GC-MSD and, LC-MSD. The detection rate of pesticide residues were 14.8% (431/2,914). The order of agricultural products in which the pesticide residues were detected was perilla leaves 40.0% (28/70), chamnamul 35.5% (11/31), amaranth 30.0% (3/10) and spinach 27.7% (38/137) etc. The percentage of products that exceeded the MRLs (maximum residue limits) were 1.0% (31/431). Those products that exceeded MRLs were ginseng (6), perilla leaves (4), leek (4), welsh onion (3) and sedeum (3) etc. The 59 kinds of the pesticides were detected on this study, 21 pesticides of them were detected over MRLs. Detection rate of fungicides (56.4%) was higher than that of insecticides (42.1%). And procymidone was detected with considerable high frequency. Additionally, residual residual violates pesticides were in the order of tolclofos-methyl, endosulfan, dimethomorph, diniconazole and fludioxonil. According to the agricultural marketing channels, detection and excess rate of them were monitored. Detection and excess rate of samples circulated in agricultural traditional market were highest. The estimated daily intakes (EDI) of the pesticides were compared to personal acceptable daily intakes (PADI) in order to risk assessment by food consumption. Diazinon in Korean cabbage showed the highest %ADI, 2.9901 and others showed below 3.0 %ADI. Overall, these results indicate that residue levels of pesticides detected were evaluated as safe.

• Journal of fish pathology
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• v.22 no.3
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• pp.263-273
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• 2009

There is an increasing number of reports describing Streptococcus parauberis as an important pathogen of cultured olive flounder Paralichthys olivaceus and starry flounder Platichthys stellatus in Korea. We tried to determine the effects of water temperature (14${^{\circ}C}$ and 21${^{\circ}C}$) on the pathogenicity in Streptococcal disease caused by S. parauberis. We have challenged 180 olive flounder by i.p injection to $2.0{\times}10^{7}$ live cells/fish. Mortality was monitored for 21 days post challenge. And histopathological characterizations as infection degree, tissue degeneration and/or bacterial distribution were investigated with H&E stain and in situ hybridization technique. Fifty percent and 16.7% of mortality occurred within 21 days at 21${^{\circ}C}$ and 14${^{\circ}C}$ water temperature, respectively. In most cases, the typical symptoms of olive flounder infected with S. parauberis were darkness of the skin, lethargy, mild abdominal distension cause by ascites, splenomegaly, congested liver and internal organs paleness. The pericardial sac contained large amounts of cloudy fluid. Numerous whitish nodules, which were variable in size and often confluent, were randomly scattered throughout the myocardium. Especially, pericarditis and/or myocarditis was observed in all tested fishes after death. Positive in reaction with S. parauberis were found in all tissues in situ hybridization analysis. The relative numbers of S. parauberis in heart were much more than in liver, spleen, kidney and stomach. We evaluated that S. parauberis strain causes serious damage in the pericardium, shortness of breath and the blood disorder. Therefore, pericarditis and myocarditis caused by S. parauberis were closely related to mortality of olive flounder.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.185-191
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• 2010

In this study, monitoring of food additives as an artificial sweetener on favorite foods of children, which are deal at retail store and stationery store around eliminatory school, was performed. We analyzed aspartame, potassium acesulfame, sodium saccharin, and cyclamate from candys, biscuits, chocolates and others. Total 604 items as targeted food were collected from the other country; 285 items of candys, 131 items of biscuits, 74 items of chocolates., 114 items of others. Targeted foods were classified by manufacture nation; 308 samples from domestic products, 211 from China, 26 from Indonesia, and 59 items from other nations. Artificial sweeteners were detected from 75 cases of food stuff which were 38 native product, 25 China, 9 Indonesia, and 3 others. The percentage of detected artificial sweeteners was aspartame 7.8% (47 cases), potassium acesulfame 3.0% (18 cases), sodium saccharin 1.8% (11 cases), and cyclamate 2.6% (16 cases). The detected concentration were followed [average(minimum-maximum) mg/kg]; aspartame 817 (21-4,988), potassium acesulfame 192 (24-1,136), sodium saccharin 91 (5-326), and cyclamate 926 (8-4,680). Aspartame was detected mainly on Korea foods, and cyclamate and sodium saccharin were detected from Indonesia food, artificial sweeteners were detected Chinese food, broadly. As a result, 17 cases were violated against regulatory standard of cyclamate, and sodium saccharin. Considering average body weight (36.9 kg) and daily intake of biscuits (15.6 g) for elementary student, ratio of estimated daily intake and acceptable daily intake was 0.86% for aspartame, 0.54% for potassium acesulfame, 0.77% for sodium saccharin, and 3.56% for cyclamate.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.365-374
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• 2020

This study was conducted to monitor the residual pesticides on a total of 320 stalk and stem vegetables from January 2019 to December 2019 in the Incheon metropolitan area. Pesticide residues in samples were analyzed by the multi-residue method for 373 pesticides using GC-MS/MS, LC-MS/MS, GC-ECD, GC-NPD and HPLC-UVD. Risk assessment was also carried out based on the amount of stalk and stem vegetables consumed. The linearity correlation coefficient for the calibration curve was 0.9951 to 1.0000, LOD 0.002 to 0.022 mg/kg, LOQ 0.005 to 0.066 mg/kg and recovery was 82.0 to 108.0%. According to the monitoring of pesticides, 36 (11.3%) of 320 were detected with pesticide residues and 3 (0.9%) samples exceeded the maximum residual limit. The detection frequency for Chinese chives and Welsh onion was higher than that for other stalk and stem vegetables. The frequently detected pesticides were etofenprox, procymidone, fludioxonil, and pendimethalin. As a tool of risk assessment through the consumption of pesticide detectable agricultural products, the ratio of estimated daily intake (EDI) to acceptable daily intake (ADI) was calculated in the range of 0.0062-24.1423%. These results indicate that there is no particular health risk through consumption of commercial stalk and stem vegetables detected with pesticide residues.

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.27-34
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• 2008

A Korean urban contamination model METRO-K (${\underline{M}}odel$ for ${\underline{E}}stimates$ the ${\underline{T}}ransient$ Behavior of ${\underline{R}}adi{\underline{O}}active$ Materials in the ${\underline{K}}orean$ Urban Environment, which is capable of calculating the exposure doses resulting from radioactive contamination in an urban environment, is taking part in a model testing program EMRAS (${\underline{E}}nvironmental$ ${\underline{M}}odelling$ for ${\underline{RA}}diation$ ${\underline{S}}afety$) oragnized by the IAEA (${\underline{I}}nternational$ ${\underline{A}}tomic$ ${\underline{E}}nergy$ ${\underline{A}}gency$). For radioactive contamination scenarios of Pripyat districts and a hypothetical RDD (${\underline{R}}adiological$ ${\underline{D}}ispersal$ ${\underline{D}}evice$), the predicted results using METRO-K were submitted to the EMRAS's Urban Contamination Working Group. In this paper, the predicted results for the contamination scenarios of a Pripyat district were shown in case of both without remediation measures and with ones. Comparing with the predictied results of the models that have taken part in EMRAS program, a feasibility for decision-making support of METRO-K was investigated. As a predicted result of METRO-K, to take immediately remediation measures following a radioactive contamination, if possible, might be one of the best ways to reduce exposure dose. It was found that the discrepancies of predicted results among the models are resulted from 1) modeling approaches and applied parameter values, 2) exposure pathways which are considered in models, 3) assumptions of assessor such as contamination surfaces which might affect to an exposure receptor and their sizes, 4) parameter values which are related with remediation measures applied through literature survey. It was indentified that a Korean urban contamination model METRO-K is a useful tool for dicision-making support through the participation of EMRAS program.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.148-154
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• 2008

This study was carried out to investigate the residue patterns of two insecticides, lambda-cyhalothrin and deltamethrin, commonly used for lettuce, under greenhouse conditions. The pesticides were sprayed with dilution of recommended and doubled doses onto lettuce. Their detection limits were $0.001\;mg{\cdot}kg^{-1}$ and mean recoveries at the fortification levels of 0.2 and $1.0\;mg{\cdot}kg^{-1}$ were from 101.17 to 104.25 and from 99.70 to 103.77%, respectively. The pesticides were gradually decreased in lettuce with time. Biological half-lives of lambda-cyhalothrin and deltamethrin were 1.7 and 1.4 days at the recommended dose and 1.8 and 1.4 days at the doubled dose, respectively. Initial residue amounts of lambda-cyhalothrin and deltamethrin at the recommended and doubled doses exceeded their MRLs. However, the residue levels of the pesticides in the crop sampled at harvest were less than their MRLs. The ratios of the estimated daily intake (EDI) to acceptable daily intake (ADI) by intake the crop harvested 10 days after spraying were less than 1% of their ADIs.