• Journal of agricultural medicine and community health
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• v.12 no.1
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• pp.80-93
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• 1987

Mass chemotherapy of Clonorchis sinensis infection in Korea was started in 1982 with 40mg/kg body weight single dose administration scheme of praziquantel. The purpose of this study was to investigate the efficiency of current mass chemotherapy project and compare the epidemiological changes in endemic area of Ckmorchis sinensis. This study was performed at Kimhae-city and Samrangjin-eup of Miryang-gun, Kyongnam province, highly endemic area of C. sinensis located southeastern part of Korea from July to October of 1986. The therapy project of Kimhae area was performed in 1984, whereas that of Samrangjin was done in 1985 by stool examination of the Korea Association for Parasite Eradication(KAPE) and drug administration of local health centre. The results obtained were as follows; 1) As a results of stool examination from 234 specimens obtained in Kimhae area, the infection rate has decreased to 34.2%from 45.6p in 1983, but the infection rate of C. sinensis from 341 specimens obtained in Samrangjin area did not decrease (58.1%in 1986 490%in 1983). 2) The study in Kimhae area showed that the average EPG decreased remarkably from 4,858 to 1,340 and those classified above the category of heavy infection decreased also from 14.0pp to 1.7%. The study in Samrangjin area showed that the average EPG did decrease drastically from 9,597 to 6,498 and those classified above the category of heavy infection did not go down drastically from 25.2% to 14.2%. 3) The study in Kimhae area showed decrease of Cs.$D._{50}$ in comparison to that in 1983, wheareas Cs.$D._{50}$ in Samrangjin area showed no much difference compared to that in 1983. The intensities of endemicity were represented with the regression equation calculated with the cumulative percentages of EPG count. Regression equation was Y=4.49+1.19 log x in Kimhae area and Y=3.66+127 log x in Samrangjin area. 4) The two stage catalytic model was applied and the calculation lead to the equation $Y=5.33(e^{-0.018t}-e^{-0.016t})$ in Kimhae area and $Y=1.25(e^{-0.010t}-e^{-0.018t})$ in Kimhae area and $Y=125(e^{-0.010t}-e^{-0.050t})$ in Samrangjin area 5) The infection rate of cercaria in P.manchouric-us studied in Kimhae area showed 1.25% which is not much different from that in previous years, wheareas the infection rate of metacercaria in P. parva studied in the same area this year showed 2.5-20.2/gm of flesh in comparison to 64/gm of flesh in 1983. 6) Data of C. sinensis infection on the reservoir host in Kimhae area showed 4 out of 18 dogs, 1 out of 18 rats and that in Samrangjin area showed 2 out of 18 dogs respectively. 7) Among the inhabitants who were under mass chemotherapy in Kimhae area, 71out of them, upon stool examination, showed infection rate of 66.2% and those classified above the category of heavy infection, 2.4%. In comparison to infection rate of 33.7% and those classified above the category of heavy infection, which is 1.0%, obtained from those not under mass chemotherapy showed higher infection rate and somewhat equal distribution of intensity of infection. The above statements reflect the fact that individual therapy besides mass chemotherapy was prevalent in that area. 8) On the other side, the studies in Samrangjin area showed infection rate of 68.7% and those above the category of heavy infection, which is 6.1%, in comparison to infection rate of 58.3% and those above the category of heavy infection, which is 16.5%, in those not under mass chemotherapy. the above reflects that although a good deal of inhabit-ants were classified under light or moderate infection category, those above the category of heavy infection, yet, numbered a lot, and individual chemotherapy has not been going on. In conclusion, it was suggested that the number of reinfected inhabitants among those under mass chemotherapy were numerous. Accordingly, the reinforcement of health education should be followed with mass chemotherapy. The facts of high infection rate exemplified by 65% and high number of those above the category of heavy infection in Samrangjin area say that reevaluation of dosage, number of medication and intervals should be necessarily made.

• Journal of Preventive Medicine and Public Health
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• v.31 no.1 s.60
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• pp.91-103
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• 1998

Under experimental conditions, UVB radiation, a type of ultra violet radiation, has shown to .elate with the occurrence of skin erythema (sun-burn) in human and skin cancer in experimental animal. Cumulative exposure to UVB is also believed to be at least partly responsible for the 'aging' process of the skin in human. It has also been observed to have an effect of altering DNA (deoxyribonucleic acid). UVB radiation is both an initiator and a promoter of non-melanoma skin cancer. Meta-analysis is a new discipline that critically reviews and statistically combines the results of previous researches. A recent review of meta-analysis in the field of public health emphasized its growing importance. Using a meta-analysis in this study, we explored more reliable dose-response relationships between UVB radiation and skin cancer incidence. We estimated skin cancer incidence using measured UVB radiation dose at a local area of Seoul (Shin chou-dong). The studies showing the dose-response relationships between UVB radiation and non-melanoma skin cancer incidence were searched and selected for a meta-analysis. The data for 7 reported epidemiological studies of three counties (USA, England, Australia) were pooled to estimated the risk. We estimated rate of incidence change of skin cancer using pooled data by meta-analysis method, and exponential and power models. Using either model, the regression coefficients for UVB did not differ significantly by gender and age. In each analysis of variance, non-melanoma skin cancer incidence after removing the gender and age and UVB effects was significant (p>0.01). The coefficients for UVB dose were estimated $2.07\times10^{-6}$ by the exponential model and 2.49 by the power model. At a local area of Seoul (Shinchon-Dong), BAF value were estimated 1.90 and 2.51 by the exponential and power model, respectively. The estimated BAP value were increased statistical power than that of primary studies that using a meta-analysis method.

• Journal of Internet Computing and Services
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• v.21 no.5
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• pp.139-148
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• 2020

Infectious diseases have long plagued mankind, and predicting and preventing them has been a big challenge for mankind. For this reasen, various studies have been conducted so far to predict infectious diseases. Most of the early studies relied on epidemiological data from the Centers for Disease Control and Prevention (CDC), and the problem was that the data provided by the CDC was updated only once a week, making it difficult to predict the number of real-time disease outbreaks. However, with the emergence of various Internet media due to the recent development of IT technology, studies have been conducted to predict the occurrence of infectious diseases through web data, and most of the studies we have researched have been using single Web data to predict diseases. However, disease forecasting through a single Web data has the disadvantage of having difficulty collecting large amounts of learning data and making accurate predictions through models for recent outbreaks such as "COVID-19". Thus, we would like to demonstrate through experiments that models that use multiple Web data to predict the occurrence of infectious diseases through LSTM models are more accurate than those that use single Web data and suggest models suitable for predicting infectious diseases. In this experiment, we predicted the occurrence of "Malaria" and "Epidemic-parotitis" using a single web data model and the model we propose. A total of 104 weeks of NEWS, SNS, and search query data were collected, of which 75 weeks were used as learning data and 29 weeks were used as verification data. In the experiment we predicted verification data using our proposed model and single web data, Pearson correlation coefficient for the predicted results of our proposed model showed the highest similarity at 0.94, 0.86, and RMSE was also the lowest at 0.19, 0.07.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.4
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• pp.118-129
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• 2016

Many epidemiological studies, relying on administrative air pollution monitoring data, have reported the association between particulate matter ($PM_{10}$) air pollution and human health. These monitoring data were collected at a limited number of fixed sites, whereas government-generated health data are aggregated at the area level. To link these two data types for assessing health effects, it is necessary to estimate area-level concentrations of $PM_{10}$. In this study, we estimated district (Gu)-level $PM_{10}$ concentrations using a previously developed pointwise exposure prediction model for $PM_{10}$ and three types of point locations in Seoul, Korea. These points included 16,230 centroids of the largest census output residential areas, 422 community service centers, and 610 centroids on the 1km grid. After creating three types of points, we predicted $PM_{10}$ annual average concentrations at all locations and calculated Gu averages of predicted $PM_{10}$ concentrations as representative Gu-estimates. Then, we compared estimates to each other and to measurements. Prediction-based Gu-level estimates showed higher correlations with measurement-based estimates as prediction locations became more population representative ($R^2=0.06-0.59$). Among the three estimates, grid-based estimates gave lowest correlations compared to the other two(0.35-0.47). This study provides an approach for estimating area-level air pollution concentrations and assesses air pollution health effects using national-scale administrative health data.

• Journal of agricultural medicine and community health
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• v.11 no.1
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• pp.3-11
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• 1986

In order to observe the infestation rate and intensity of C. sinensis in Yeoju Eup, Kyung-gi Do, 9,512 stool specimens were collected from the inhabitants through student's helps. The specimens were examined by cellophane thick smear technique and Stoll's egg dilution technique. The epidemiological status was analysed statistically by the regession equation and catalytic curve with the results obtained from this area. The results are as follows: 1) Collection rate oft he stool samples was 66.5%, 9.512 out of 14,300 inhabintants complied with our survey. 2) The infestation rate of C.sinensis was 5.0%, and for male 7.8%, for female 2.3%. 3) Average E.P.G. by Stoll's egg dilution technique in this area was 1,572, and for male 1,853, for female 676. 4) The degree of the intensity of C. sinensis infection by E.P.G. count was distributed as 65.2% in light infection, 32.0 % in moderate infection, 2.8% in heavy infection and none in very heavy infection. 5) The intensity of endemicity in this area was represented with the regression equation calculated with cumulative percentages of E.P.G. counts. Regression equation was y=3.887+1.695 log x and Cs. $D_{50}$ was 4.54. 6) The two-stage catalytic model was applied and the calculation lead to the equation $y=0.267(e^{-0.004t}-e^{-0.019t})$; a=0.004 < b=0.019. 7) Other helminthic infection rate in this area was 1.4% in A.lumbricoides 2.7% in T. trichiura, 1.6% in M. yokogawai md 0.2% in Taenia sp. respectively.

• BMB Reports
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• v.29 no.2
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• pp.105-110
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• 1996

Polyclonal antiserum R101 against aflatoxin $B_1$ ($AFB_1$) was raised in New Zealand white rabbits after injection of bovine serum albumin-$AFB_1$ conjugate. Competitive ELISA (enzyme linked immuno-sorbent assay) demonstrated that antiserum R101 has the highest binding for $AFB_1$ (50% inhibition at 170 fmol) and aflatoxicol II (50% inhibition at 112 fmol). It also reacts with other aflatoxins such as $AFB_2$, $AFG_1$, $AFG_2$, and aflatoxin metabolites ($AFM_1$, $AFM_2$, $AFP_1$, and $AFQ_1$), but it does not cross-react with $AFG_2a$. Using this antiserum, aflatoxins were quantitated in 100 urine samples of undergraduate students at the College of Pharmacy, Sung Kyun Kwan University, Republic of Korea. By ELISA, $AFB_1$ and its metabolites were detected in human urine samples (N=100, male=89, female=11, ages=20~31 yrs) with a range of 1.4~200.6 ng/kg/day (mean$\pm$SD=$18.11{\pm}33.01\;ng\;AFB_1/kg/day$ in males, $3.82{\pm}2.65\;ng/kg/day$ in females). Assuming that urinary excretion is about 7.6% of $AFB_1$ intake (Groopman et al., 1992), we estimated that Koreans were daily exposed to a total dietary $AFB_1$ of $240.20{\pm}438.67\;ng/kg/day$ in males and $50.35{\pm}29.88\;ng/kg/day$ in females, respectively. When the human monitoring data was applied to a linear regression model of Y=21.67X-10.04 {Y=liver cancer incidence per 100,000, X=Log $AFB_1$ intake (ng/kg/day), r=0.99} developed from previously reported epidemiological data, calculated liver cancer incidences attributed to $AFB_1$ exposure were 41.56/100,000 in males and 26.84/100,000 in females. The incidences were similarly correlated with liver cancer mortality rates of 43.43/100,000 in males and 11.23/100,000 in females in Korea. These results suggest that aflatoxin exposure may be an important risk factor for the high incidence of liver cancer in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3931-3936
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• 2012

Background: Epidemiological studies evaluating the association of two variants rs9340799 and rs2234693 on estrogen receptor 1 (ESR1) with prostate risk have generated inconsistent results. Methods: A meta-analysis was here conducted to systematically evaluate the relationship of these two variants with prostate cancer susceptibility. Results: For rs9340799, heterozygosity of T/C carriers showed a significant increased prostate cancer risk with a pooled odds ratio (OR) of 1.34 (95% CI = 1.06-1.69) while homozygote C/C carriers showed an increased but not statistically significant association with prostate cancer risk (pooled OR = 1.29, 95% CI = 0.94-1.79). Compared to the homozygous TT carriers, the allele C carriers showed a 31% increased risk for prostate cancer (pooled OR = 1.31, 95% CI = 1.06-1.63). No significant association between the rs2234693 and prostate cancer risk was found with the pooled OR of 1.15 (95% CI = 0.97-1.39, T/C and C/C vs. T/T) under the dominant genetic model. Compared to the homozygote T/T carriers, the heterozygous T/C carriers did not show any significantly different risk of prostate cancer (pooled OR = 1.13, 95% CI = 0.94-1.36) and the homozygous C/C carriers also did not show a significant change for prostate cancer risk compared to the wide-type T/T carriers (pooled OR = 1.26, 95% CI = 0.98-1.62). Conclusion: These data suggested that variant rs9340799, but not rs2234693, on ESR1 confers an elevated risk of prostate cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6743-6749
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• 2013

Molecular epidemiological studies have shown that gene polymorphisms of estrogen receptor alpha gene (ESR-${\alpha}$) are associated with breast cancer risk. However, previous results from many molecular studies have been inconsistent. In this study, we examined two polymorphisms (PvuII and XbaI RFLPs) of the ESR-${\alpha}$ gene in 542 breast cancer cases and 1,016 controls from China. Associations between the polymorphisms and breast cancer risk were calculated with an unconditional logistic regression model. Linkage disequilibrium and haplotypes were analyzed with the SHEsis software. In addition, we also performed a systematic meta-analysis of 24 published studies evaluating the association. No significant associations were found between the PvuII polymorphism and breast cancer risk. However, a significantly decreased risk of breast cancer was observed among carriers of the XbaI 'G' allele (age-adjusted OR = 0.80; 95% CI = 0.66- 0.97) compared with carriers of the 'A' allele. Haplotype analysis showed significantly decreased cancer risk for carriers of the 'CG' haplotype (OR = 0.79; 95% CI = 0.66- 0.96). In the systematic meta-analysis, the XbaI 'G' allele was associated with an overall significantly decreased risk of breast cancer (OR = 0.90, 95% CI = 0.82- 1.00). In addition, the PvuII 'C' allele showed a 0.96- fold decreased disease risk (95% CI = 0.92- 0.99). In subgroup analysis, an association between the PvuII 'C' and XbaI 'G' alleles and breast cancer risk was significant in Asians ('C' vs. 'T': OR = 0.93, 95% CI = 0.85- 1.00; 'G' vs. 'A': OR = 0.82, 95% CI = 0.68- 0.98), but not in Euro-Americans. Thus, our results provide evidence that ESR-${\alpha}$ polymorphisms are associated with susceptibility to breast cancer. These associations may largely depend on population characteristics and geographic location.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.544-552
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• 1998

A random study of 574 dairy farms in Gyeongnam area was designed to determine 1) management factors that may be associated with the occurrence of drug residues; 2) the dairy farmer's attitudes and knowledge about residues; 3) how these variables influence the occurrence of residues in dairy cattle. Management factors perceived as having the greatest influence on drug residues in milk were insufficient knowledge about withdrawal periods, errors due to hired help, insufficient identification and record of animals treated for mastitis, dry cow treatment for mastitis, and metritis treatment. Seventy-one percent of farms with residues problem used mixed own feeds compared with twenty-nine percent of farms with premedicated feeds. Factors significantly associated with the occurrence of residues were herd size, increased number of hired persons, increased frequency of use of mixed-own feeds, category of medicated feed, and producer's attitude toward the public health significance of residues. Our findings suggest that residue occurrence was mainly associated with errors due to hired help, insufficient knowledge about withdrawal periods, poor animal identification and records of treatment animals and use of medicated feeds. Any residue avodiance educational program needs to stress how to deal with these factors. This educational program should be directed to dairy farmers and employees, especially temporary employees. In addition, Dairy farmer's attitudes and knowledge about drug residues need to be improved. More evidence on the public healths significance of residues should be available to them. Because belife in importance of public healths concerns was related to successful residue avidance and because 81.3% of the dairy farmers with residue problem thought public healths concerns were less important than economic ones, it would be helpful to provide educational programs specifically directed to this issue. it may be useful to provide programs not only for the dairy farmers but also change of their concerns about on the public healths.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.415-420
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• 2010

In Korea, oysters are used as an ingredient of Kimchi (Korean pickled cabbage) in early winter. Although viral contamination of oysters, including contamination by norovirus, can provoke gastroenteric illness, little is known of the epidemiological relationship to outbreaks. We postulated that Kimchi ripening can reduce the infectivity of norovirus, in order to test this hypothesis, we carried out a model experiment. Since norovirus is currently regarded as non-culturable, feline calicivirus (FCV) was used as a surrogate to examine the activation of norovirus with Kimchi ripening. In commercial well-prepared Kimchi, the infectivity ($TCID_{50}$) of FCV decreased by 2 log every 12 hours and reached the limit of detection after 48 hours during over-aging at $25^{\circ}C$. During storage at $4^{\circ}C$, the infectivity ($TCID_{50}$) of FCV decreased slowly and reached 5.00 $TCID_{50}$ after 48 hours. The low pH appears to affect the infectivity of FCV directly via organic acids produced by ripening during over-aging and storage. In neutralized lab-prepared Kimchi (pH 7.0), the infectivity ($TCID_{50}$) of FCV also decreased and reached the limit of detection after 72 hours at $4^{\circ}C$. This indicates that there are substances beside organic acids in Kimchi that originate from the raw materials and are produced during ripening. Among the raw materials, salt-fermented anchovies and garlic showed high direct antiviral activity. The main factor decreasing the infectivity of FCV in Kimchi was the high acidity caused by organic acids, regardless of the type, produced by ripening. Furthermore, unknown secondary products of microorganisms associated with Kimchi ripening and antiviral materials originating from raw material might contribute to the decreased infectivity of FCV, the surrogate of norovirus.