• 대한수의학회지
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• 제58권4호
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• pp.193-199
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• 2018

As animal welfare issue becomes important, the European Union bans conventional cages for laying hens from 2012. So the alternative housing systems like floor pens, aviaries or free range systems have been suggested. From 2011 to 2014, we monitored 20 welfare-oriented laying hen farms in South Korea to figure out serological status of major viral diseases. During this period, total 3,219 blood samples were collected from the randomly selected chickens to test and evaluate the hemagglutination inhibition titers for low pathogenic avian influenza, Newcastle disease and egg drop syndrome '76. A total of 2,926 blood samples were tested through enzyme linked immunosorbent assay (ELISA) to assess the serological status of infectious bronchitis (IB). The distribution of ELISA titers for IB was various from almost 0 to 20,000 through the all weeks of age. Also, the antibody coefficient of variation for most of the diseases in this study was higher than those of typical cage layers. As this study was the first surveillance for major avian viral diseases of the animal welfare-oriented farms in South Korea, the results obtained from this study will help to determine what information and resources are needed to maintain better biosecurity and to improve the health and welfare of laying hen flocks.

• BMB Reports
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• 제40권5호
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• pp.662-669
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• 2007

Although the function of cellular prion protein (PrP$^C$) and the pathogenesis of prion diseases have been widely described, the mechanisms are not fully clarified. In this study, increases of the portion of non-glycosylated prion protein deposited in the hamster brains infected with scrapie strain 263K were described. To elucidate the pathological role of glycosylation profile of PrP, wild type human PrP (HuPrP) and two genetic engineering generated non-glycosylated PrP mutants (N181Q/N197Q and T183A/T199A) were transiently expressed in human astrocytoma cell line SF126. The results revealed that expressions of non-glycosylated PrP induced significantly more apoptosis cells than that of wild type PrP. It illustrated that Bcl-2 proteins might be involved in the apoptosis pathway of non-glycosylated PrPs. Our data highlights that removal of glycosylation of prion protein provokes cells apoptosis.

• Tuberculosis and Respiratory Diseases
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• 제80권4호
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• pp.358-367
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• 2017

Background: Bacterial pneumonia occurring after respiratory viral infection is common. However, the predominant bacterial species causing pneumonia secondary to respiratory viral infections other than influenza remain unknown. The purpose of this study was to know whether the pathogens causing post-viral bacterial pneumonia vary according to the type of respiratory virus. Methods: Study subjects were 5,298 patients, who underwent multiplex real-time polymerase chain reaction for simultaneous detection of respiratory viruses, among who visited the emergency department or outpatient clinic with respiratory symptoms at Ulsan University Hospital between April 2013 and March 2016. The patients' medical records were retrospectively reviewed. Results: A total of 251 clinically significant bacteria were identified in 233 patients with post-viral bacterial pneumonia. Mycoplasma pneumoniae was the most frequent bacterium in patients aged <16 years, regardless of the preceding virus type (p=0.630). In patients aged ${\geq}16years$, the isolated bacteria varied according to the preceding virus type. The major results were as follows (p<0.001): pneumonia in patients with influenza virus (type A/B), rhinovirus, and human metapneumovirus infections was caused by similar bacteria, and the findings indicated that Staphylococcus aureus pneumonia was very common in these patients. In contrast, coronavirus, parainfluenza virus, and respiratory syncytial virus infections were associated with pneumonia caused by gram-negative bacteria. Conclusion: The pathogens causing post-viral bacterial pneumonia vary according to the type of preceding respiratory virus. This information could help in selecting empirical antibiotics in patients with post-viral pneumonia.

• Macromolecular Research
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• 제15권2호
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• pp.100-108
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• 2007

Gene therapy has become a promising strategy for the treatment of genetically based diseases, such as cancer, which are currently considered incurable. A major obstacle in the field of cancer gene therapy is the development of a safe and efficient delivery system for therapeutic gene transfer. Non-viral vectors have attracted great interest, as they are simple to prepare, stable, easy to modify and relatively safe compared to viral vectors. In this review, an insight into the strategies developed for polyethylenimine (PEI)-based non-viral vectors has been provide, including improvement of the polyplex properties by incorporating hydrophilic spacer, poly(ethylene glycol) (PEG). Moreover, this review will summarize the strategies for the tumor targeting. Specifically, a targeted polymeric gene delivery system, PEI-g-PEG-RGD, will be introduced as an efficient gene delivery vector for tumor therapy, including its functional analysis both in vitro and in vivo.

• 현장농수산연구지
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• 제5권1호
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• pp.57-63
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• 2003

The bovine rotavirus(BRV), bovine coronavirus(BCV) and bovine viral diarrhea virus(BVDV) are main viruses of bovine viral diarrhea disease. These viruses could be rapidly amplified by the reverse transcriptase polymerase chain reaction(RT-PCR). This study was conducted to develop rapid and accurate diagnostic methods of these viral diseases by multiplex RT-PCR. Specific primers were designed based on the sequences reported by Chang KO et. al. (1997) and Schroeder BA, et. al. (1990), RNA were prepared from the cultured viruses, first-stranded DNAs were synthesised by reverse transcriptase. PCR were conducted to amplify specific regions of the viruses by multiplex. Three bands such as 1,062bp for BRV, 458bp for BCV, and 300bp for BVDV were successfully produced by multiplex RT-PCR. In conclusion, this result suggested that these viruses could be diagnosed rapidly and accurately by multiplex RT-PCR.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7045-7056
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• 2013

Since the first report of RNA interference (RNAi) less than a decade ago, this type of molecular intervention has been introduced to repress gene expression in vitro and also for in vivo studies in mammals. Understanding the mechanisms of action of synthetic small interfering RNAs (siRNAs) underlies use as therapeutic agents in the areas of cancer and viral infection. Recent studies have also promoted different theories about cell-specific targeting of siRNAs. Design and delivery strategies for successful treatment of human diseases are becomingmore established and relationships between miRNA and RNAi pathways have been revealed as virus-host cell interactions. Although both are well conserved in plants, invertebrates and mammals, there is also variabilityand a more complete understanding of differences will be needed for optimal application. RNA interference (RNAi) is rapid, cheap and selective in complex biological systems and has created new insight sin fields of cancer research, genetic disorders, virology and drug design. Our knowledge about the role of miRNAs and siRNAs pathways in virus-host cell interactions in virus infected cells is incomplete. There are different viral diseases but few antiviral drugs are available. For example, acyclovir for herpes viruses, alpha-interferon for hepatitis C and B viruses and anti-retroviral for HIV are accessible. Also cancer is obviously an important target for siRNA-based therapies, but the main problem in cancer therapy is targeting metastatic cells which spread from the original tumor. There are also other possible reservations and problems that might delay or even hinder siRNA-based therapies for the treatment of certain conditions; however, this remains the most promising approach for a wide range of diseases. Clearly, more studies must be done to allow efficient delivery and better understanding of unwanted side effects of siRNA-based therapies. In this review miRNA and RNAi biology, experimental design, anti-viral and anti-cancer effects are discussed.

• Journal of Preventive Medicine and Public Health
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• 제34권2호
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• pp.131-140
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• 2001

Objectives : During March-May, 2000, a measles outbreak occurred at Youngduk, Korea. This county is divided into two areas with different historical and socioeconomic background. The outbreak occurred in one of these areas. We conducted a comparative epidemiologic study on the two areas in order to evaluate the factors related to the epidemic. Materials and Methods : We selected two groups, grades 3 and 5 in a primary schools in each area. We investigated outbreak-related factors using parent-questionnaires, the vaccination history from the student's health record and the records concerning the recent measles-outbreak from the local health center. Serologic test on measles-IgG and -IgM antibody was done. Results : The infection rate was 31.5% for the epidemic area and 3.7% for non-the epidemic area according to clinical or serological criteria (p<0.001). No difference was seen in the measles vaccination rate, residence at the time of vaccination or past measles infection history between the two areas. In the epidemic area, the attack rate for the 4-6 year-old MMR booster group(20.5%) was higher than the non-booster group(32.4%), but was not found significantly. Vaccine efficacy was 29.6% in the epidemic area and 87.0% in the non-epidemic area (p<0.001). The IgG level and positive rate were significantly different between the two areas (median 10727 IU/ml, 98.9% in epidemic area; median 346 IU/ml, 85.9% in the non-epidemic area, p<0.001). However, the IgG level and positive rate between the measles-cases and non-cases were not significantly different. Conclusions : This outbreak took place in mostly vaccinated children. These results suggest that a reduction of herd immunity for immunity failure after vaccination may be one of the feasible factors related to the outbreak pattern in the two areas. The results of the IgG level and positive rate suggest that re-establishment of a normal value for IgG level and of a qualitative method for IgG are needed.

• 미생물학회지
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• 제42권3호
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• pp.177-184
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• 2006

항구 도시인 부산의 바이러스성 성병 감염 현황과 고위험군 지표로서 HPV, HSV 및 HBV 감염자의 성별, 연령대별 유형율 조사 등 기초자료를 확보하여 성매개감염증 사업관리 및 전파방지에 중요한 자료를 제공하고자 한다. 자궁경부도찰물 674건 중 HPV 23건(3.4%)과 HSV 1 2형 3건(0.4%) 9건(1.3%)이 각각 분리되었으며, 혈청 586건 중 HSV IgM 121건(3.6%), HSV-1 IgG 487건(83.1%), HSV-2 IgG 135건(23.0%), HBsAg 26건(4.4%), HBeAg 7건 (1.2%) 등이 검출되었다. HPV 유전자형별 분포도는 고위험군이 15종(13명), 저위험군이 6종(3명)으로 나타났으며, 복합감염은 7명이었다. 연령별 발생분포는 자궁경부도찰물의 경우 20대 이하가 24건(7.2%), 혈청의 경우 40대 이상이 101건(100%)으로 가장 높았다. 그리고 업소별 분포도는 자궁경부도찰물에서 보건소의 검진대상자(유흥업소종사자)들이 감염율이 가장 높았고, 혈청에서는 대용성병진료소의 검진대상자(특수업태부)가 감염율이 가장 높았다.

• 한국가금학회지
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• 제16권3호
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• pp.175-192
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• 1989

한국 양계의 성장기이었던 1971년부터 1988년까지 최근 18연간 국내 양계농가로부터 농촌진흥청 가축위생연구소에 의뢰된 닭 가검물의 병성감정결과 질병검색된 총 9,012건 중 전염성 질병으로 진단된 6,181건에 대하여 검색 연도별, 계절별 및 일영별 검색상황을 조사 분석하였던 바 다음과 같은 결과를 얻었다. 1. 연도별 전염성 질병의 검색률은 49.3％(1973연)∼78.3％(1985년)로써 연평균 68.6％로 나타나 비전염성 질병(31.42％)보다는 월등히 높았다. 2. 전염성 질병 중에는 세균성이 32.6％(16.2∼42.5％)로 가장 높았고 다음 바이러스성 질병이 26.3％(21.8∼38.1％)이었으며 기생충성 및 곰팡이성 질병은 각각 7.7％ 및 2.1％의 낮은 검색율을 나타내었다. 3. 세균성 질병으로는 마이코프라스마병, 대장균증 및 포도상구균증의 연평균검색률이 각각 8.8％, 8.5％, 5.8％로 가장 높았으며, 다음 살모넬라균증, 추백리, 난황염 및 수란괌염이 각각 0.8∼1.5％ 이었고 피부염(0.2％) 및 연쇄상구균증(0.1％)은 매우 낮은 빈도로 검색되었다. 4. 바이러스성 질병중에는 임파성 백혈병 및 마렉병이 각각 연평균 7.5％ 및 7.2％로 가장 많았고 다음 뉴캣슬병(4.4％), 전염성 후두기관염(2.0％), 전염성 낭병(1. 7％) 및 조뇌척수염(1.0％)의 순이었으며 그 외 전염성 기관지염, 산란저하증 '76 및 봉입체간염 등이 각각 1.0％, 미만으로 검색되었다. 5. 기생충성 질병의 검색률에 있어서는 닭 콕시듐병이 연평균 4.5％로 가장 높았고 다음 회염증이 1.4％이었다. 그 외에 류코싸이토준병 흑두병, 맹장충증 및 외부기생충증이 각각 0.2∼0.7％의 낮은 비율로 검색되었다. 곰팡이성 질병으로는 곰팡이성 폐렴이 연평균 2.0％, 다음으로 캔디다증이 0.1％ 검색되었다. 6. 계절별 전염성 질병의 검색은 하계 및 추계절에 각각 27.7％ 검색되어 가장 높았으며 다음 동계(23.5％) 및 춘계절의 순으로 낮았다. 이들중 세균성, 바이러스성 및 곰팡이성 질병은 이와 유사한 경향이었으나 기생충성 질병은 하계 및 추계절에서의 검색률이 각각 34.3％ 및 39.5％로 다른 계절에 비하여 월등히 높았다. 7. 세균성 포도장구균증은 추계절에서의 검색율이 가장 높았으며, 바이러스성 질병으로는 마렉병, 전염성 후두기관염 및 전염성 낭병은 하계절에, 그리고 임파성백혈병, 계두 및 산란저하증 '76은 추계절에서 가장 높았으며 전염성 기관지염은 동계절에 최고빈도로 검색되었다. 기생충성 질병에 있어서는 콕시듐병을 위시하여 회충증, 류코싸이토준병 및 흑두병등 대부분의 주요질병이 하계절 및 추계절에 가장 많이 검색되었다. 8. 닭 일영별 전염성 질병의 검색률은 육성계(30∼150일영)에서 47.4％의 가장 높은 검색률을 나타내었고 다음 성계(150일영이상)에서 35.3％ 및 유추(30 일영미만)에서 17.3％의 순이었다. 이중 세균성 및 기생충성 질병은 육성계에서의 검색률이 가장 높았으나, 바이러스성 질병은 육성계 및 성계에서 거의 같은 비율로 높았으며 곰팡이성 질병은 유추에서 가장 높은 검색률을 나타내었다.

• Parasites, Hosts and Diseases
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• 제48권2호
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• pp.113-120
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• 2010

To understand protozoan, viral, and bacterial infections in diarrheal patients, we analyzed positivity and mixedinfection status with 3 protozoans, 4 viruses, and 10 bacteria in hospitalized diarrheal patients during 2004-2006 in the Republic of Korea. A total of 76,652 stool samples were collected from 96 hospitals across the nation. The positivity for protozoa, viruses, and bacteria was 129, 1,759, and 1,797 per 10,000 persons, respectively. Especially, Cryptosporidium parvum was highly mixed-infected with rotavirus among pediatric diarrheal patients (29.5 per 100 C. parvum positive cases), and Entamoeba histolytica was mixed-infected with Clostridium perfringens (10.3 per 100 E. histolytica positive cases) in protozoan-diarrheal patients. Those infected with rotavirus and C. perfringens constituted relatively high proportions among mixed infection cases from January to April. The positivity for rotavirus among viral infection for those aged $\leq$ 5 years was significantly higher, while C. perfringens among bacterial infection was higher for $\geq$ 50 years. The information for association of viral and bacterial infections with enteropathogenic protozoa in diarrheal patients may contribute to improvement of care for diarrhea as well as development of control strategies for diarrheal diseases in Korea.