• Parasites, Hosts and Diseases
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• v.46 no.4
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• pp.289-291
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• 2008

The Tamjin River which flows from Jangheung-gun via Gangjin-gun to the South Sea was reported to be a highly endemic area of Metagonimus yokogawai infection in 1977 and 1985. However, there were no recent studies demonstrating how much change occurred in the endemicity, in terms of prevalence and worm burden, of metagonimiasis in this river basin. Thus, a small-scale epidemiological survey was carried out on some residents along the Tamjin River basin in order to determine the current status of M. yokogawai infection. A total of 48 fecal samples were collected and examined by the Kato-Katz thick smear and formalin-ether sedimentation techniques. The egg positive rate of all helminths was 50.0%, and that of M. yokogawai was 37.5%, followed by C. sinensis 22.9% and G. seoi 4.2%. To obtain the adult flukes of M. yokogawai, 6 egg positive cases were treated with praziquantel 10 mg/kg in a single dose and purged with magnesium sulfate. A total of 5,225 adult flukes (average 871 specimens per person) of M. yokogawai were collected from their diarrheic stools. Compared with the data reported in 1977 and 1985, the individual worm burdens appeared to have decreased remarkably, although the prevalence did not decrease at all. It is suggested that the endemicity of M. yokogawai infection along the Tamjin River has been reduced. To confirm this suggestion, the status of infection in snail and fish intermediate hosts should be investigated.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.512-519
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• 2018

Phthalates widely used in the manufacture of plastics have deeply penetrated into our everyday lives. Recently, a concern over the toxicity of phthalates on thyroid, has been raised but in most of cases, the doses employed were unrealistically high. To investigate the effects of phthalates on thyroid, we investigated the effects of the repeated oral exposure to low to high doses (0.3, 3, 30 and 150 mg/kg) di-2-ethylhexylphthalate (DEHP) from weaning to maturity for 90 days in juvenile rats on the thyroid. The histological examination revealed that DEHP significantly induced hyperplasia in the thyroid from the doses of 30 mg/kg, which was confirmed with Ki67 staining. In line with this finding, increased mRNA expression of thyrotropin releasing hormone (Trh) was observed in the thyroid of female at 0.3 mg/kg and 150 mg/kg as determined by RNAseq analysis. Moreover, significantly increased expression of parathyroid hormone (Pth) in the female at 0.3 mg/kg, and thyroglobulin (Tg) and thyroid hormone responsive (Thrsp) in the male at 0.3 mg/kg were noted in the blood, of which changes were substantially attenuated at 150 m/kg, alluding the meaningful effects of low dose DEHP on the thyroid hormone regulation. Urinary excretion of mono-2-ethylhexyl-phthalate (MEHP), a major metabolite of DEHP was determined to be 4.10 and 12.26 ppb in male, 6.65 and 324 ppb in female at 0.3 and 30 mg/kg DEHP, respectively, which fell within reported human urine levels. Collectively, these results suggest a potential adverse effects of low dose phthalates on the thyroid.

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.242-247
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• 2003

Murine encephalomyocarditis virus (EMCV) has been used as a surrogate for hepatitis A virus (HAV) for the validation of virus removal and/or inactivation during the manufacturing process of biopharmaceuticals. Recently international regulation for the validation of HAV safety has been reinforced because of the reported cases of HAV transmission to hemophiliac patients who had received ntihemophilic factors prepared from human plasma. The purpose of the present study was to compare the resistance of HAV and EMCV to various viral inactivation processes and then to standardize the HAV validation method. HAV was more resistant than EMCV to pasteurization (60oC heat treatment for 10 hr), low pH incubation (pH 3.9 at 25oC for 14 days), 0.1 M NaOH treatment, and lyophilization. EMCV was completely inactivated to undetectable levels within 2 hr of pasteurization, however, HAV was completely inactivated to undetectable levels after 5 hr treatment. EMCV was completely inactivated to undetectable levels within 15 min of 0.1 M NaOH treatment, however, residual infectivity of HAV still remained even after 120 min of treatment. The log reduction factors achieved during low pH incubation were 1.63 for HAV and 3.84 for EMCV. Also the log reduction factors achieved during a lyophilization process of antihemophilic factor VIII were 1.21 for HAV and 4.57 for EMCV. These results indicate that HAV rather than EMCV should be used for the virus validation study and the validation results obtained using EMCV should be precisely reviewed.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.175-179
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• 2012

Adenoviruses are an important cause of respiratory tract infections, particularly in infants, young children, and immuno-compromised patients. In this study, we investigated the characteristics of adenoviruses isolated from outpatients with acute respiratory illness in Gyeonggi province of South Korea during 2009-2011. Adenoviruses were detected in 102 of 1,622 (6.3%) specimens by using PCR or real-time PCR with viral specific primers. 76 isolates were obtained from 102 specimens using the A549 cells. Serotypic distributions of isolated adenovirus were analyzed by sequencing of hexon gene. Six different serotypes were identified, which included adenovirus serotypes 1-6. Adenovirus 3 (n=40, 52.6%) was the predominant serotype. The predominant types of adenovirus every year were serotypes 1 and 3 in 2009, serotype 3 in 2010, and serotype 5 in 2011, respectively. Adenoviruses 1, 2, 4, 5, and 6 were isolated sporadically throughout the study period. Adenovirus 3 was present both during outbreaks and in sporadic cases. These results indicate that adenovirus 3 played major causative agent of adenovirus outbreaks in Gyeonggi province of South Korea during 2009-2011. Continuous surveillance for specific serotypes of adenovirus that can cause outbreaks is important.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.347-353
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• 2002

Dominant rock types of stones used presently for cooking utensils in Korea are pyroxenite, breccia and biotite diorite. Pyroxenite and biotite diorite relatively abundant in mafic minerals have higher specific gravities of 3.0 than breccia of 2.5. Breccia shows the highest absorption (2.9%) among three stones used as cooking utensils and pH value of three stone types shows the alkaline range of 9.7 to 9.9. Among the studied stones used for cooking utensils, biotite diorite is the most durable against abrasion and has the highest strength and therefore, it is expected to be used effectively for the longest time except for other specific causes. Heavy metals such as Cu, Pb, Co, Cr and Ni were leached lower than their detection limit (0.1 ppm) regardless of reaction time and initial pH value of solution. But the leached contents of Fe are various with rock types and leaching conditions and those by acidic solution are generally 1.8 to 31 times higher than those by neutral solution. Breccia and biotite diorite show the highest leached content of Fe in cases of neutral and acidic solutions, respectively. Standard criteria of leached heavy metals and macrominerals should be studied thoroughly to utilize stones for cooking utensils of high quality which are harmless to the human body. Also it is required to examine mon detailed abiochemical properties of various stone types used for cooking utensils.

• Health Policy and Management
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• v.22 no.1
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• pp.1-28
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• 2012

Since its establishment in 1948, World Health Organization (WHO) has tried and facilitated international cooperation of public health under the goal of "the highest attainable health," and gained outcomes like the eradication of smallpox and polio, turning itself into the representative of international public health. However, there was discord between member nations during the cold war era, and the status of WHO experienced rise and fall after its establishment. WHO, the representative international health organization, also has not been freed from influences from international regime changes, which means that the discussion on the internal causes of WHO functionings should be expanded more. In this study, functionalism was tested as one of international relations theory that tries to explain the establishment and role of WHO. Especially, this study analyzed the problems and problem-solving process that WHO had to face by using Imber's five steps theory that arranged chronologically the theory of Mitrany. We mainly investigated the secondary source that described historic facts on the rise and fall of WHO in terms of roles and functionings during establishment of WHO, the cold war era, and international cooperation of public health. The roles of WHO were analyzed by selecting the gains of WHO in the post cold war era. The functionalism arrangement of Imber was appropriate to some extent in explaining the establishment and role of WHO. The first step was International Sanitary Conference in 1851 that made nations to recognize international cooperation of public health, and the second step was the establishment of WHO that handles public health as an international organization. Recent cases of the Framework Convention on Tobacco Control and International Health Regulations showed that each nation agreed with an international norm that they had to cooperate each other to tackle infectious diseases and smoking, and this implies that these were emergence of global governance. This process was the third step of Imber's theory (nations had a gain from international cooperation would agree with the expansion of authority of international organization). However, the last two steps of the theory are still not realized. The partial success of WHO was based on the functional elements that WHO deals with non-political elements, human resources centering on professionals, and democratic decision making process. This essential and non-political characteristics mean that necessity of international cooperation catalyzed by WHO would continue despite of the global governance era when global health governance get faced more challenges.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.705-711
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• 2007

We should treat carefully the one related to human rights among a large number of decision-making in our daily lives. As it is necessary to obtain physical evidences in the process of criminal investigation for solving a certain crime based on the principle of evidence, it leads to an increase in demand for forensic science and forensic geology. Forensic geology could be regarded as a fusion discipline of geology and forensic investigation and it is principally concerned to the study on the connection of a suspect and a crime scene with soil evidence which could be experimented using geological data and methods. So these results could be used as valuable information in a court. After its academic foundation has been builded since the last 1970s, its research objects have been expanded from soil evidence like rocks, minerals, soils, sediments to sociocultural, political, military and medical objects like ancient relics, mines, corpses. Its role is expanded from the simple finding of a particular location to the examination of archaeological theories and historical facts, the testimony of the cause of environmental pollution and the chronic demonstration of geological distribution of plants and anthropological origination. And these bring this discipline promptly to accept developed geological methodologies and to satisfy various forensic geological needs. Specialized forensic investigation institutes work actively for the R&D activities of forensic geology. In Korea, national institute of scientific investigation works a small part of forensic geological activities in total activities of forensic investigation. In conclusion, we concern to the importance of systematic discussion of building in proper position of forensic geology through its R&D methods, application cases of its performance and etc. based on geological characteristics in our country by a specialized geoscience institute.

• Journal of the Korean GEO-environmental Society
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• v.7 no.6
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• pp.45-56
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• 2006

Recently, the more potential waste sites are being required as increasing the demand of better human life. But the construction of waste disposals has many restrictions because of lack of good quality clay and high cost of liners. So, in this study, we studied the liner materials to develop more cheaper soil liner that can be satisfied the environmental criterion for the coefficient of permeability and shear strength. A series of compaction test and triaxial (consolidation, permeability, and shear) tests were performed to obtain the optimized weight ratio of Bentonite-Soil mixture (B/S) including the least amount of bentonite. A series of soil tests were performed to acquire the appropriate weathered granite soil-bentonite mixture that is satisfied the environmental criterion of soil liner($k=1{\times}10^{-7}cm/sec$). At first, weathered granite soils were classified with four different particle-size soils, and B/S ratio was increased as 5% step for each particle-size. The test results showed that in case of weathered granite soil passing through No. 100 sieve, B/S=15% satisfied the soil liner criterion. The measured coefficient of permeability and the Chapuis's two equations were also compared. And a predicting equation for the coefficient of permeability was suggested, which is suitable for the mixture soil with the B/S ratio used in this study. The optimal weight ratio for the mixture soils used in this study was 15% in the both cases of permeability and shear strength.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.2
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• pp.126-132
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• 2016

Objective: The purpose of this study was to identify useful clinical factors for the identification of patients with polycystic ovary syndrome (PCOS) who would benefit from in vitro maturation (IVM) treatment without exhibiting compromised pregnancy outcomes. Methods: A retrospective cohort study was performed of 186 consecutive patients with PCOS who underwent human chorionic gonadotropin-primed IVM treatment between March 2010 and March 2014. Only the first IVM cycle of each patient was included in this study. A retrospective case-control study was subsequently conducted to compare pregnancy outcomes between IVM and conventional in vitro fertilization (IVF) cycles. Results: Through logistic regression analyses, we arrived at the novel finding that serum $anti-M{\ddot{u}}llerian$ hormone (AMH) levels and the number of fertilized oocytes in IVM were independent predictive factors for live birth with unstandardized coefficients of 0.078 (95% confidence interval [CI], 1.005-1.164; p=0.037) and 0.113 (95% CI, 1.038-1.208; p=0.003), respectively. Furthermore, these two parameters were able to discriminate patients who experienced live births from non-pregnant IVM patients using cut-off levels of 8.5 ng/mL and five fertilized oocytes, respectively. A subsequent retrospective case-control study of patients with PCOS who had serum AMH levels ${\geq}8.5ng/mL$ showed that IVM had pregnancy outcomes comparable to conventional IVF, and that no cases of ovarian hyperstimulation syndrome were observed. Conclusion: Serum AMH levels are a useful factor for predicting pregnancy outcomes in PCOS patients before the beginning of an IVM cycle. IVM may be an alternative to conventional IVF for PCOS patients if the patients are properly selected according to predictive factors such as serum AMH levels.

• Proceedings of the Ginseng society Conference
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• 1974.09a
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• pp.9-22
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• 1974

Unlike the tissue culture in animals and human being, in higher plants various parts of the plant are cultured for varied purposes, and they are named variously depending on which parts are used as explants or what purposes they are cultured for. Followings are some of the names of culture used frequently: organ culture, tissue culture, callus culture, single cell culture, meristem culture, mericlone culture, ovary culture, ovule culture, embryo culture, endosperm culture, anther culture, pollen culture, protoplast culture, etc.. As the names of the culture indicate, in some kinds of culture the explants used for culture are actually not tissues, but organs, single cells, or protoplasts. It seems, however, convenient to call all of the above-mentioned cultures grossly as tissue culture. Several kinds of tissue culture were attempted using Panax ginseng as material and some of the results were summarized below. 1. Callus culture After dormancy of the sed was broken, whole embryo or parts (hypocotyl, cotyledon and epicotyl) of partly grown embryo were cultured in the media supplemented with growth regulators. Rapid swelling occurred in a few weeks, but most of the swelling was observed only in the basal part of epicotyl, changes in the other parts of embryo appearing in much later stages. The swelling or increase in size, however, was resulted not from the divisions of cells, but from the mere expansion of cell. Real calli were formed about two months after inoculation of explants. Callus tissues developed from cortex, pith, and vascular bundle in the cases of hypo- and epicotyl, from mesophyl tissue in the case of cotyledon. Shoots developed more easily from cotyledons regardless of whether they are detached from or attached to the embryo proper. 2. Culture in the Knudson C medium When cotyledons, detached from or attached to the embryo proper, were cultured in the growth regulator-free Knudson C medium comprision only several kinds of mineral compounds and sucrose, shoot primordium or callus developed profusely and finally plantlets were produced directly from shoot primordium or indirectly through callus. In this medium epidermal cells as well as mesophyl cells of the cotyledon became meristematic and divided, changing into multinucleate cells or multicellular bodies, developing eventually into either shoot primordia or calli. 3. Anther culture Anthers were cultured in the media supplemented with various growth regulators applied singly or in combinations. Callus was formed mostly in the connective tissue of anther. Cells of anther wall layers changed in appearance, but no division occurred. Microspores of all stages in development were not changed, ruling out the possibility that microspore-originated callus might be formed. 4. Isolation of protoplast Protoplasts were isolated from young root, leaf, and epicotyl, using 0.7M D-mannitols as osmoticum and using macerozyme and cellulase respectively for maceration and digestion of the cell wall. Production in large number of naked intact protoplast was rather difficult as compared with other plant species. Fusion of protoplasts occurred infrequently mainly due to the fewer number of naked protoplasts in the solution.