• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.3
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• pp.12-24
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• 2013

Eradication of endemic malaria was declared in mid 1980's in Korea, but the number of malaria cases has been oscillating for the past 10 years since the reemergence of the disease in early 1990's. The occurrence of malaria has been concentrated near the demilitarized zone(DMZ), and the regional characteristics of the disease are evident. Considering the spatial variations of malaria incidence across the high-risk areas, the hotspot of the disease, it seems that the occurrence of the disease is influenced by the natural and human environment in the region. Malaria is an infectious disease that is transmitted to humans by the bites of vector-mosquitoes carrying malaria parasites, and it depends on specific climatic and sociodemographic factors. Malaria transmission is highly climate-sensitive, and temperature is the most important component. In addition, human contacts with vector-mosquitoes and the distance between human residence and mosquito habitats are crucial conditions determining malaria incidence rates. The present study aimed to test a hypothesis that the spatial characteristics of malaria incidence depended on local climatic conditions, relative proportions of mosquito habitats, and the distance between mosquito habitats and human residence using meteorological and satellite-based land cover data.

• Korean Journal of Poultry Science
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• v.31 no.2
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• pp.119-128
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• 2004

Highly Pathogenic Avian Influenza (HPAI) is a very acute systemic disease in poultry, particularly in chickens and turkeys caused by HPAI viruses. An outbreak of HPAI caused by subtype H5N1, was first reported in a broiler breeder farm on December 10, 2003 in Korea, although there had been twenty one outbreaks of the disease reported in the world before. Since mid-December 2003, eight Asian countries have confirmed outbreaks of HPAI due to the same subtype. The outbreak has also resulted in at least twenty three fatal human cases in Vietnam and Thailand as of May 17, 2004 according to the WHO. Regarding the first outbreak of recent Asian HPAI, it has been suspected that some Asian countries with the exception of Korea and Japan veiled the fact of HPAI outbreaks since the last half of 2003, even though it was first reported in Korea. There have been total nineteen outbreaks of HPAI among chicken and duck farms in 10 provinces in Korea since Dec. 2003 and approximately 5,280,000 birds were slaughtered from 392 farms for eradication of the disease and preemptive culling. The origin of the H5Nl HPAI virus introduced into the country are unknown and still under epidemiological investigation. Current status of outbreaks and characteristics of HPAI will be reviewed and discussed on the basis of genetic, virological, clinicopathological, and ecological aspect, as well as future measures for surveillance and prevention of the disease in Korea.

• Korean Journal of Veterinary Service
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• v.26 no.2
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• pp.163-184
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• 2003

This study was conducted to survey the farm which suffered from disease similar to classical swine fever(CSF) in Gyeongbuk province. Clinical signs appeared first in a few number of growing pigs which showed specific signs of diarrhea, depression, sleepiness, and reluctance to get up or to eat. Younger piglets may have appeared chilled, shiver and huddle together. As the disease progresses the affected pig's skin went red and purple. In histopathological signs, there were many haemorrhages throughout the body and larger haemorrhages in some organs such as lymph nodes. And there is a precipitous fall in the number of circulating leukocytes in the blood. In spite of insisting of farmer which did not vaccinate to classical swine fever, significant antibody production was detected in these affected pigs at enzyme-linked immuonsorbent assay. According to the above results at first glance, these affected pig suspected with CSF in clinical signs and histopathological lesions only. Because the symptoms and post-mortem picture were very similar to CSF, these false positive results would have been dangerous to diagnostician. But by reverse transcriptase polymerase chain reaction(RT-PCR) and comparative nucleotide sequence analysis, the disease was correctly diagnosed with post-weaning multisystemic wasting syndrome(PMWS) and porcine reproductive and respiratory syndrome(PRRS) compoundly. And the antigen which were detected the lesion similar to CSF virus, was confirmed with LOM vaccine strain of CSF. In most national CSF eradication program and in countries which are free of the CSF virus, vaccination against CSF is not practiced and generally is not allowed. But now in Korea, routine vaccination is practiced because of outbreaking the CSF repeatedly. When CSF is diagnosed the whole herd and other in contact animal are slaughtered continuously.

• Korean Journal of Veterinary Service
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• v.30 no.2
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• pp.243-249
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• 2007

The tube agglutination test has been used for bovine brucellosis diagnosis in Korea since middle 1950s. The reported high specificity was its value in eradication program. However, the reading of reaction mostly depends on personal experience, thus here we report a way to improve accuracy and uniformity of reading. The tube agglutination was conducted according to the protocol provided by Korean Ministry of Agriculture and Forestry. The intensity of reaction was measured by spectrophotometer. The relationship between turbidity and percentage clearing was generally in direct proportion and linear. The correspondent percent transmittance at 75, 50, and 25% clearing were 91, 82, and 73, respectively. Then, the degree of percentage of clearing at given international unit was measured. With about 1.5 unit of serum, the maximum percentage clearing was observed. The international unit showing 25, 50, and 75 percentage clearing were 0.61, 0.83 and 1.35, respectively. Based on the information obtained using international standard serum, the calculation of international unit of test serum was available. According to the protocol for bovine brucellosis diagnosis which provided by Korean Ministry of Agriculture and Forestry, the available range of detectable international unit was between 15 and 538. And the corresponding international units for suspicious case ranged between 42 and 127. Of the 35 sera from B abortus infected cattle, about half of them had more than 538 international units. Collectively, the reading of turbidity using spectrophotometer and application to international unit improved accuracy and uniformity of reading.

• Korean Journal of Veterinary Research
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• v.39 no.2
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• pp.247-256
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• 1999

A disease of young Holstein calves characterized by recurrent pneumonia, ulcerative and granulomatous stomatitis, enteritis with bacterial overgrowth, periodontitis, delayed wound healing, persistent neutrophilia and death at an early age had been originally described in 1983 and again in 1987. Most of these calves had stunted growth and a persistent, progressive neutrophilia (often exceeding 100,000/ml). By investigation of pedigrees, all of the affected calves have now been traced to a common sire and confirmed by polymerase chain reaction (PCR) diagnostic DNA testing to be homozygous carriers of a defective allele for bovine CD18. Neutrophils from these calves have several functional deficits and, most importantly, fail to adhere in a ${\beta}_2$-integrin dependent manner. The ${\beta}_2$-integrins represent a family of glycoproteins which participate in various leukocyte adhesion reactions during host defense. The presence or absence of ${\beta}_2$-integrin molecules can be demonstrated on the surface of neutrophils, monocytes and lymphocytes from normal or affected calves using specific monoclonal antibodies and flow cytometry, or by colloidal gold immunolabeling and scanning electron microscopy in backscatter mode. Deficiency of the ${\beta}_2$-integrins on all leukocyte types in Holstein calves is analogous to leukocyte adhesion deficiency (LAD) seen in humans. Neutrophils in bovine (BLAD) and human LAD patients are unable to adhere to the endothelial lining of the cardiovascular system thus interrupting egression of neutrophils into infected tissues. Other leukocytes, while still deficient in expression of the ${\beta}_2$-integrins, are still able to efficiently egress from the blood stream due to interactions of other adhesion molecules that are not as highly expressed on neutrophils. Both BLAD cattle and LAD children (who do not receive bone marrow transplants) often die at an early age as a result of the failure of neutrophils to extravasate into infected tissues. In 1991, Shuster, et $al^{27}$, identified two point mutations within the alleles encoding bovine CD18 in a Holstein calf afflicted with leukocyte adhesion deficiency. One mutation causes an aspartic acid to glycine substitution at amino acid 128 (D128G) in an extracellular region of this adhesion glycoprotein that is highly conserved (> 95% identity) between humans, cattle and mice. The other mutation is silent. Numerous calves with clinical symptoms of leukocyte adhesion deficiency have since been tested and all have been found homozygous for the D128G allele. In addition, calves homozygous far the D128G allele have been identified during widespread DNA testing in the United States. All cattle with the mutant allele are related to one bull, who through artificial insemination (A.I.), sired many calves in the 1950's and 1960's. The carrier frequency of the D128G CD18 allele among U.S. Holstein cattle had reached approximately 15% among active A.I. bulls and 8% among cows. By 1993, the organization of the dairy industry and the diagnostic test developed to genotype cattle, enabled virtually complete eradication of bovine leukocyte adhesion deficiency among current and future A.I. bulls.

• 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.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.1
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• pp.1-17
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• 2020

Three-dimensional microscopic approaches in histopathology display multiplex properties that present puzzling questions for specimens as related to their comprehensive volumetric information. This information includes spatial distribution of molecules, three-dimensional co-localization, structural formation and whole data set that cannot be determined by two-dimensional section slides due to the inevitable loss of spatial information. Advancement of optical instruments such as two-photon microscopy and high performance objectives with motorized correction collars have narrowed the gap between optical theories and the actual reality of deep tissue imaging. However, the benefits gained by a prolonged working distance, two-photon laser and optimized beam alignment are inevitably diminished because of the light scattering phenomenon that is deeply related to the refractive index mismatch between each cellular component and the surrounding medium. From the first approaches with simple crude refractive index matching techniques to the recent cutting-edge integrated tissue clearing methods, an achievement of transparency without morphological denaturation and eradication of natural and fixation-induced nonspecific autofluorescence out of real signal are key factors to determine the perfection of tissue clearing and the immunofluorescent staining for high contrast images. When performing integrated laboratory workflow of tissue for processing frozen and formalin-fixed tissues, clear lipid-exchanged acrylamide-hybridized rigid imaging/immunostaining/in situ hybridization-compatible tissue hydrogel (CLARITY), an equipment-based tissue clearing method, is compatible with routine procedures in a histopathology laboratory.

• Journal of Veterinary Science
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• v.22 no.6
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• pp.41.1-41.14
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• 2021

Background: Our previously prepared ceftiofur (CEF) hydrochloride oily suspension shows potential wide applications for controlling swine Streptococcus suis infections, while the irrational dose has not been formulated. Objectives: The rational dose regimens of CEF oily suspension against S. suis were systematically studied using a pharmacokinetic-pharmacodynamic model method. Methods: The healthy and infected pigs were intramuscularly administered CEF hydrochloride oily suspension at a single dose of 5 mg/kg, and then the plasma and pulmonary epithelial lining fluid (PELF) were collected at different times. The minimum inhibitory concentration (MIC), minimal bactericidal concentration, mutant prevention concentration (MPC), post-antibiotic effect (PAE), and time-killing curves were determined. Subsequently, the area under the curve by the MIC (AUC_0-24h/MIC) values of desfuroylceftiofur (DFC) in the PELF was obtained by integrating in vivo pharmacokinetic data of the infected pigs and ex vivo pharmacodynamic data using the sigmoid E_max (Hill) equation. The dose was calculated based on the AUC_0-24h/MIC values for bacteriostatic action, bactericidal action, and bacterial elimination. Results: The peak concentration, the area under the concentration-time curve, and the time to peak for PELF's DFC were 24.76 ± 0.92 ㎍/mL, 811.99 ± 54.70 ㎍·h/mL, and 8.00 h in healthy pigs, and 33.04 ± 0.99 ㎍/mL, 735.85 ± 26.20 ㎍·h/mL, and 8.00 h in infected pigs, respectively. The MIC of PELF's DFC against S. suis strain was 0.25 ㎍/mL. There was strong concentration-dependent activity as determined by MPC, PAE, and the time-killing curves. The AUC_0-24h/MIC values of PELF's DFC for bacteriostatic activity, bactericidal activity, and virtual eradication of bacteria were 6.54 h, 9.69 h, and 11.49 h, respectively. Thus, a dosage regimen of 1.94 mg/kg every 72 h could be sufficient to reach bactericidal activity. Conclusions: A rational dosage regimen was recommended, and it could assist in increasing the treatment effectiveness of CEF hydrochloride oily suspension against S. Suis infections.

• The Korean journal of helicobacter and upper gastrointestinal research
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• v.18 no.4
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• pp.277-279
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• 2018

전 세계적으로 Helicobacter pylori의 항생제 내성률은 지속적으로 증가하고 있으며, 기존의 제균 치료에 실패한 H. pylori 감염 환자들에 대한 효과적인 구제요법(rescue therapy)의 필요성 역시 증가하고 있다. 이 연구는 두 개 기관, 공개, 평행 그룹, 무작위 배정 연구로서 불응성 H. pylori 감염 환자들의 구제요법으로 유전자형 내성을 기반한 치료(genotype resistance-guided therapy)와 경험적 치료(empirical therapy) 중 어느 것이 보다 효과적인지를 비교하고자 하였다. 2012년 10월부터 2017년 9월까지 20세 이상의 불응성 H. pylori 감염 환자들을 대상으로 하였으며, 불응성 H. pylori 감염은 과거 두 종류 이상의 H. pylori 제균 치료를 받았음에도 불구하고 H. pylori 제균에 실패한 환자들로 정의하였다. 이들에게서 한 군은 14일간의 유전자형 내성을 기반한 순차 치료(n=21 in trial 1, n=205 in trial 2)를, 다른 한 군은 환자들의 과거 제균 치료 종류를 감안한 14일간의 경험적 순차 치료(n=20 in trial 1, n=205 in trial 2)를 시행하였다. 순차 치료법은 첫 7일은 esomeprazole 40 mg과 amoxicillin 1 g을 하루 두 번 복용한 다음, 나머지 7일은 esomeprazole 40 mg과 metronidazole 500 mg, 그리고 1) levofloxacin 250 mg 또는 2) clarithromycin 500 mg 또는 3) tetracycline 500 mg을 하루 두 번 복용하는 것으로 구성하였다. 23S ribosomal RNA (rRNA)나 gyrase A에 대한 내성 관련 돌연변이 여부는 direct sequencing을 통한 중합효소연쇄반응(polymerase chain reaction, PCR) 검사를 이용하였고, 제균 성공 여부는 요소호기검사를 통해 확인하였다. 일차 결과 지표는 치료 방법에 따른 제균율로 정하였다. Trial 1에서는 tetracycline 대신 doxycycline 100 mg을 사용하였는데, 제균 성공률이 유전자형 내성을 기반한 치료군에서는 17명(81%), 경험적 치료군에서는 12명(60%)으로 나타났다(P=0.181). 하지만, 다른 순차 치료군들과 비교하였을 때, doxycycline을 포함한 순차 치료군의 제균율이 현저히 낮은 것으로 나타나서(15/26, 57.7%) doxycycline을 포함한 순차 치료법은 종결하기로 하고, trial 2부터는 doxycycline 대신 tetracycline으로 교체하여 연구를 지속하였다. Trial 2의 intention-to-treat (ITT) 분석 결과, 유전자형 내성을 기반한 치료군에서는 160/205명(78%), 경험적 치료군에서는 148/205명(72.2%)으로 두 그룹 간의 통계적인 제균율의 차이는 보여주지 못하였다(P=0.170). 부작용 및 환자 순응도에서도 양 군 간의 의미 있는 차이는 없었다. 따라서, 두 종류 이상 H. pylori 제균 치료에 실패한 환자들이라고 할지라도 기존의 제균 치료력을 바탕으로 적절한 경험적 치료를 시행하는 것은 유전자형 내성을 기반한 치료 정도의 효과는 있으며 접근성, 비용, 환자들의 선호도 등의 여러 가지 부가적인 사항들을 고려할 때, 제균 치료력을 고려한 경험적 치료는 간단한 수준의 유전자형 내성을 기반한 치료의 대안으로 받아들여질 수 있을 것으로 제안하였다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.5
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• pp.417-430
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• 2019

The policies developed for the treatment of Helicobacter pylori infection in adults may not be the most suitable ones to treat children and adolescents. Methods used to treat children and adolescents in Europe and North America may not be appropriate for treating children and adolescents in Korea due to differences in epidemiological characteristics of H. pylori between regions. Moreover, the agreed standard guidelines for the treatment of H. pylori infection in children and adolescents in Korea have not been established yet. In this study, the optimal treatment strategy for H. pylori infection control in children and adolescents in Korea is discussed based on these guidelines, and recent progress on the use and misuse of antimicrobial agents is elaborated. Non-invasive as well as invasive diagnostic test and treatment strategy for H. pylori infection are not recommendable in children aged less than ten years or children with body weight under 35 kg, except in cases of clinically suspected or endoscopically identified peptic ulcers. The uncertainty, whether enough antimicrobial concentrations to eradicate H. pylori can be maintained when administered according to body weight-based dosing, and the costs and adverse effects outweighing the anticipated benefits of treatment make it difficult to decide to eradicate H. pylori in a positive noninvasive diagnostic test in this age group. However, adolescents over ten years of age or with a bodyweight of more than 35 kg can be managed aggressively as adults, because they can tolerate the adult doses of anti-H. pylori therapy. In adolescents, the prevention of future peptic ulcers and gastric cancers is expected after the eradication of H. pylori. Bismuth-based quadruple therapy (bismuth-proton pump inhibitor-amoxicillin/tetracycline-metronidazole) with maximal tolerable doses and optimal dose intervals of 14 days is recommended, because in Korea, the antibiotic susceptibility test for H. pylori is not performed at the initial diagnostic evaluation. If the first-line treatment fails, concomitant therapy plus bismuth can be attempted for 14 days as an empirical rescue therapy. Finally, the salvage therapy, if needed, must be administered after the H. pylori antibiotic susceptibility test.