• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.508-517
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• 1997

Hepatitis B virus(HBV) infection is one of the major health problems in Korea and HBsAg positive rate was known to be about $5\sim15%$ in general population. This study was conducted to identify the positive rates of serum HBsAg and anti-HBs among community population regarded as having hish HBV vaccination rate than in previous decade, using EIA(Enzyme immunoassay) method, in Seo-Gu, Taegu, Korea. The study subjects were 1,160 who visited Seo-Gu Health Center for check-up serologic markers of hepatitis 3. The data were obtained from the serologic test for hepatitis markers and questionnaire survey was conducted to obtain the general characteristics, vaccination history, past history of hepatitis and other liver disease, and exposure history to risk factors of hepatitis of the study subjects. The positive rates of HBsAg and anti-HBs were 5.2% and 62.4% respectively. The positive rates of HBsAg for male and female were 6.6% and 4.3% respectively. The age was divided into two groups as group I (less than 15 years old), group II (more than 16 years old) according to the hypothesis that these two groups might be different in HBV vaccination rate. HBV vaccination rates for group I and II were 83.1% and 52.3%. The positive rates of HBsAg for group I and II were 2.6% and 6.5%. The positive rates of HBsAg for the vaccinated people of the group I and II were 2.2% and 3.5%, the positive rates of anti-HBs for the vaccinated people of the group I and II were 70.1% and 71.1% respectively. The most significant factor in positive rate of HBsAg was 'hepatitis carrier in family'. Multiple logistic regression analysis revealed that 'hepatitis history' and 'hepatitis carrier in family' were significant variables for positivity of HBsAg, and 'hepatitis B vaccination' was only a significant variable for positivity of anti-HBs.

• Journal of Environmental Health Sciences
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• v.43 no.1
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• pp.1-22
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• 2017

'The worstest environment disaster', 'World's first biocide massacre', 'Home-based Sewol ferry disaster' are all phrases attached to the recent humidifier disinfectant disaster. In the spring of 2011, four of 8 pregnant women including 1 adult man passed away at a university hospital in Seoul due to breathing failure. Epidemiologic investigation conducted by the Korean CDC soon revealed the inhalation of humidifier disinfectant, which had been widely used in Korea during the winter, to be responsible for the disease. As well as lung fibrosis hardening of the lungs, other diseases including asthma, rhinitis, skin disease, liver disease, fetal disease or cancers have been researched for their relation with exposure to the products. By February 9, 2017, 5,342 cases had registered for health problems and 1,131 of them were already dead (20.8% mortality rate). Based on studies by government agencies and a telephone survey of the general population by Seoul National University and civic groups, around 20% of the general public of Korea has used these products. Since the market release of the first product by SK Chemical in 1994, over 7.1 million items from around 20 brands were sold up to 2011. Most of the products were manufactured by well-known large conglomerates such as SK, Lotte, Samsung, Shinsegye, LG, and GS, as well as some European companies including UK-based Reckitt Benckiser and TESCO, the German firm Henkel, the Danish firm KeTox, and an Irish company. Even though this disaster was unveiled in 2011 by the Korean government, the issue of the victims was neglected for over five years. In 2016, an unexpected but intensive investigation by prosecutors found that Reckitt Benckiser manipulated and concealed animal tests for its own brand and brought several university experts and company employees to court. The matter was an intense social issue in Korea from May to June with a surge in media coverage. The prosecutor's investigation and a nationwide boycott campaign organized by victims and environmental groups against Reckitt Benckiser, whose product had been used by more than 70% of victims, led to the producer's official apology and a compensation scheme. A legislative investigation organized after the April 2016 national election revealed the producers' faults and the government's responsibility, but failed to meet expectations. A special law for the victims passed the National Assembly in January 2017 and a punitive system together with a massive environmental epidemiology investigation are expected to be the only solutions for this tragedy. Sciences of medicine, toxicology and environmental health have provided decisive evidence so far, but for the remaining problems the perspectives of social sciences such as sociology and jurisprudence are highly necessary, similar to with the Minamata disease and Wonjin Rayon events. It may not be easy to follow this issue using unfamiliar terminology from medical and chemical science and the long, complicated history of the event. For these reasons the author has attempted to write this article in a question and answer format to render it easier to follow. The 17 questions are: Q1 What is humidifier disinfectant? Q2 What kind of health problems are caused by humidifier disinfectant? Q3 How many victims are there? Q4 What is the analysis of the 1,112 cases of death? Q5 What is the problem with the government's diagnostic criteria and the solution? Q6 Who made what brands? Q7 Has there been a recall? What is still on sale? Q8 Was safety not checked by any producers? Q9 What are the government's responsibilities? Q10 Is it true that these products were sold only in Korea? Q11 Why and how was it unveiled only in 2011 after 17 years of sales? Q12 What delayed the resolution of the victim issue? Q13 What is the background of the prosecutor's investigation in early 2016? Q14 Is it possible to report new victim cases without evidence of product purchase? Q15 What is happening with the victim issue? Q16 How does it compare with the cases of Minamata disease and Wonjin Rayon? Q17 Are there prevention measures and lessons?

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.173-178
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• 2007

Children may respond differently to the caffeine from adults because they have different physiologic makeup and are functionally immature in terms of hepatic and renal function; this leads to the slower clearance of caffeine in early life. Therefore, children are often assumed to be more susceptible to caffeine effects. Alarge number of food supplements may interfere with these processes, and therefore caffeine exposure may have more serious consequences for children than for adults, irrespective of sensitivity. However, there has never been a national dietary survey on caffeine intakes in children. The purpose of our study was to identify caffeine intakes and beverage sources of caffeine in a representative sample of children in Busan, Korea. Caffeine intakes were based only on beverages included in the Continuing Surveys of Food Intakes by individuals. The caffeine content of the beverages ranged from 2.8 to 65.2mg/100ml for cola, soft drinks, and teas. Caffeine was not completely absent from caffeine-free colas, juice, and milk. In this study, cola-type beverages were an important dietary source of caffeine in the children. Daily caffeine intake for children was estimated to range from 12.5 to 250 mg/day. In general, the acceptable daily intake (ADI) of caffeine should cover the entire population including children. Therefore, special considerations should be needed regarding the consumption of soft drinks containing caffeine to children below the 12 years of age.

• Journal of radiological science and technology
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• v.31 no.1
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• pp.11-16
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• 2008

Purpose : The aim of this study was to predict radiation dose at 1 meter with BMI(body mass index) in thyroid cancer patients treated with radio-iodine and provide the efficient guideline in the management of patients. Methods : 140 patients from thyroidectomy for thyroid cancer were enrolled. All subjects under went 150 mCi radio-iodine therapy and performed whole body scan 1 week later. BMI(weight divided by square of height) was calculated to evaluate the amount of fatty tissue indirectly. The radiation dose at 1 meter was measured initially and on 2nd days. the relation of values with BMI were analyzed statically. As for the method of statistical analysis, using Med calc Version 9,2,2,0 Program. Results : (1) The initial effective dose was inversely correlated with the BMI. Significance level was 0.0004. (2) We obtained the following formula from the data of initial effective dose and BMI: Y = -30.91X + 350.4(${\mu}Sv/h$)(Y: initial radiation dose, x: Group). (3) After 21.55 hours, than radiation dose was less than those recommended by ICRP or NRC in 53% of the population. Conclusion : Using BMI, the initial radiation dose and 2nd days dose can be predicted in thyroid cancer patients before radio-iodine therapy. It may be used for predicting the time of discharge and control the isolation room. We were able to predict the radiation exposure after discharge using this calculated value.

• Journal of Chest Surgery
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• v.38 no.4 s.249
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• pp.263-270
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• 2005

In recent years, a combination of two demographic phenomena, an increased number of older people in the population and an increase in the incidence of lung cancer with age, has made it mandatory to develop therapeutic modalities with less toxicity for the treatment of inoperable elderly patients with lung cancer. Therefore, we investigated the correlation between COX-2 expression and cytotoxicity of Nimesulide, a specific COX-2 inhibitor. Material and Method: Immunohistochemical staining of COX-2 was performed. After exposure of Nimesulide, XTT analysis, FACS analysis and Hoechst staining were carried out. Result: COX-2 protein was expressed in non-treated A549 cells strongly, but not in H1299. Cytotoxicity of Nimesulide against A549 cell and H1299 cell were similar and $IC_{50}$ of Nimesulide in both cell lines were $70.9{\mu}M$ in A549 cell line and $56.5{\mu}M$ in H1299 cell line respectively. FACS analysis showed $G_0/G_1$ arrest in both cell lines and the S phase cell fraction was decreased. Morphologic assessment of apoptosis by Hoechst 33258 staining, many apoptotic cells were detected in both cell lines. Conclusion: Selective COX-2 inhibitor, Nimesulide, can inhibit the proliferation of non-small cell lung cancer cell lines in vitro. Inhibitory effect of Nimesulide are induction of apoptosis and $G_0/G_1$ arrest. There is no correlation between COX-2 expression and cytotoxicity of Nimesulide, a specific COX-2 inhibitor. Therefore, highly selective COX-2 inhibitors such as Nimesulide can be expected to lead to even greater efficacy of their use as adjuncts to various anticancer angents and radiation therapy for the treatment of high-risk patients.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.474-479
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• 2003

Purpose : The determination of exposure and prevalence of Mycoplasma pneumoniae pneumonia of any region should be helpful for clinical diagnosis. We studied the pattern of occurrence of M. pneumoniae pneumonia among children living in southern central Korea during the last 13 years. This area has a relatively small population and less mobility compared with metropolitan areas. Methods : We performed a retrospective descriptive study of 143 patients admitted to the pediatrics ward among all the patients aged less than 15 years old diagnosed with M. pneumoniae pneumonia at our hospital, from July 1989 to June 2002. Results : The percentiles of incidence per year compared to the total patients admitted to a pediatric ward per year were 0.52% in 1989, 0.48% in 1990, 0.13% in 1991, 0% in 1992, 1.85% in 1993, 1.00% in 1994, 0.15% in 1995, 0.53% in 1996, 1.75% in 1997, 0.65% in 1998, 0.24% in 1999, 1.14% in 2000, 1.30% in 2001, 0.53% in 2002. In the peak incidence of monthly distribution for two consecutive years with outbreaks, its outbreak in the first year was concentrated in late fall and winter, but its outbreak in the following year was earlier than first year. There was peak incidence of age distribution in 4-5 years. It is shown gradually that age distributions per year of outbreak became earlier in age. Conclusion : The occurrences of M. pneumoniae pneumonia in southern central Korea occurred at 3-4 year intervals, 1-2 years in duration, compared to three year intervals, one year in duration, according to reports from metropolitan areas before 1997.

• Clinical and Experimental Pediatrics
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• v.56 no.10
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• pp.439-445
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• 2013

Purpose: Previous studies suggest that the concentration of 25-hydroxyvitamin D [25(OH)D] in cord blood may show an inverse association with respiratory tract infections (RTI) during childhood. The aim of the present study was to examine the influence of 25(OH)D concentrations in cord blood on infant RTI in a Korean birth cohort. Methods: The levels of 25(OH)D in cord blood obtained from 525 Korean newborns in the prospective COhort for Childhood Origin of Asthma and allergic diseases were examined. The primary outcome variable of interest was the prevalence of RTI at 6-month follow-up, as diagnosed by pediatricians and pediatric allergy and pulmonology specialists. RTI included acute nasopharyngitis, rhinosinusitis, otitis media, croup, tracheobronchitis, bronchiolitis, and pneumonia. Results: The median concentration of 25(OH)D in cord blood was 32.0 nmol/L (interquartile range, 21.4 to 53.2). One hundred and eighty neonates (34.3%) showed 25(OH)D concentrations less than 25.0 nmol/L, 292 (55.6%) showed 25(OH)D concentrations of 25.0-74.9 nmol/L, and 53 (10.1%) showed concentrations of ${\geq}75.0$ nmol/L. Adjusting for the season of birth, multivitamin intake during pregnancy, and exposure to passive smoking during pregnancy, 25(OH)D concentrations showed an inverse association with the risk of acquiring acute nasopharyngitis by 6 months of age (P for trend=0.0004). Conclusion: The results show that 89.9% of healthy newborns in Korea are born with vitamin D insufficiency or deficiency (55.6% and 34.3%, respectively). Cord blood vitamin D insufficiency or deficiency in healthy neonates is associated with an increased risk of acute nasopharyngitis by 6 months of age. More time spent outdoors and more intensified vitamin D supplementation for pregnant women may be needed to prevent the onset of acute nasopharyngitis in infants.

• Journal of Applied Biological Chemistry
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• v.59 no.1
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• pp.31-36
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• 2016

Chlorine dioxide has been used for a disinfectant by exhibiting antimicrobial activity and is also potent to kill insect pests infesting stored grains. This study aimed to extend the usefulness of chlorine dioxide with respect to anticancer and antiviral activities. Cytotoxicity of chlorine dioxide was assessed against five different human cancer cell lines. Chlorine dioxide exhibited significant cytotoxicity against two breast cancer cell lines (MCF-7, MDA-MB-231) and three colorectal cancer cell lines (LoVo, HCT-116, SW-480). This cytotoxicity appeared to be associated with the capacity of chlorine dioxide to induce the production of reactive oxygen species (ROS). Compared to control insect cell lines, the cancer cell lines possessed much higher levels of ROS. On the other hand, a treatment of an antioxidant, vitamin E, significantly reduced the cytotoxicity, suggesting that the cytotoxicity was induced by high levels of ROS production. Chlorine dioxide exhibited antiviral activity against different viruses. A baculovirus, Autographa californica nuclear polyhedrosis virus (AcNPV), is a dsDNA insect virus and lost its viral activity to form polyhedral viral particles in response to chlorine dioxide. The antiviral activity against AcNPV was dependent on the incubation time with chlorine dioxide. Tobacco mosaic virus is a ssRNA plant virus and was reduced in its population after exposure to chlorine dioxide along with significant decrease of viral symptoms. These results indicate that chlorine dioxide possesses anticancer and antiviral activities probably due to its inducing activity of ROS production.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.2
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• pp.109-118
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• 2012

This study achieves results from 22 maternity breast milk samples in total to demonstrate exposure level and risk assessment of PBDEs in Seoul area. PBDEs were detected in all the breast milk samples of the present study, indicating that general population in these Seoul area are widely exposed to these chemicals. Residue levels of total PBDEs (sum PBDEs from tri- to hepta-BDE) ranged of 0.84~13.1 ng/g lipid with an arithmetic mean and median of 3.56 ng/g lipid and 2.6 ng/g lipid, respectively. Global comparison shows that the levels of total PBDEs were relatively similar to those of China, Taiwan and European country (Sweden), and somewhat higher than those in some Asian (Vietnam, Philippines, and Indonesia). In the present study, however, the levels of total PBDEs in human milk are still one to two orders of magnitude lower than those in North America. Contribution rate of each congener appeared to be predominant with BDE-47, followed by BDE-153, BDE-100, BDE-99, BDE-154 and BDE-183. The sum of BDE-47 and BDE-153 accounted for more than 65% of total PBDEs in most samples. From the result of the human risk assessment of infants for total PBDEs and BDE-47 by breast milk feeding, we could find out that the average daily doses and hazard index (95th percentile) were 16.5 ng/kg bw/day and $1.2{\times}10^{-1}$ each other when nursing for 6 months after infants born. However, it was concluded that the infant health hardly had adverse seriously effects under this research condition.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.3
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• pp.65-74
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• 2017

There have been questions how entrepreneurs think, act and why individuals become entrepreneurs. The trait-based explanation of entrepreneurial activities has been main stream. However, the trait-based theory has been criticized because it assumes that entrepreneurial traits are inherited, stable and enduring over time. This research accepts the cognitive theory to see how entrepreneurs learn or accept others' values, how entrepreneurial perceptions of opportunity impact entrepreneurial actions and how individuals acquire the social legitimation of the formation of entrepreneurial activities. In order to capture the attitudes, activities and motivations of people who are involved in entrepreneurial activities, the author uses the GEM Korea 2016 data. The data from the Global Entrepreneurship Monitor(GEM) has been well known for the data to capture individuals early-stage entrepreneurial activities. This paper used the sample from the APS(Adult Population Survey) of the GEM which was completed by a representative sample of two thousand adults in Korea by the qualified survey vendor, with strict procedures and oversight by the GEM central data team. The hypotheses are tested with logit regression analysis to estimate the probability of the influence of perceptual variables such as individual perception in social learning, the opportunity recognition in the environment, and social legitimation in the entrepreneurial activities. Based on the results, individuals tend to have high entrepreneurial activities if individuals have high self-efficacy. Also, the existence of role models around the entrepreneurs encourages the individuals involve in entrepreneurial activities more however the perception of opportunity in the environment is not strongly associated with entrepreneurial activities. The media exposure of successful entrepreneurs is more important than others' perception of entrepreneurs on the desirable career option or respect from communities. This paper can contribute to the cognitive processes, particular perception about oneself, as well as perception which is impacted by a community or a society.