• 한국어병학회지
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• 제27권1호
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• pp.1-9
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• 2014

저수온기만 넙치에 대량 폐사를 일으키는 바이러스성 출혈성 패혈증을 폐사가 발생하는 $15^{\circ}C$, 폐사가 발생하지 않는 $20^{\circ}C$에서 인공감염시켜 넙치의 면역 유전자 발현 profile을 cDNA microarray 분석하였으며, 특히 저수온기에 폐사가 나타나는 원인을 면역 유전자 발현과 관련시켜 알아보고자 하였다. $15^{\circ}C$, $20^{\circ}C$의 감염 세포구에 공통으로 발현되는 유전자는 MHC class I, IL-8, myeloperoxidase 및 endonuclease G-like 유전자로 모든 세포표면에 존재하여 항원을 제시하거나 호중구 주화성을 자극하는 유전자들이었다. 항원 가공 및 제시, 항체 생성에 관여하는 MHC class II, immunoglobulin (Ig)과 retinoblastoma 등의 유전자는 $20^{\circ}C$에서는 발현이 증가하였으나 $15^{\circ}C$에서는 발현이 감소되었다. 이로부터 폐사가 발생하지 않는 $20^{\circ}C$는 바이러스 감염초기의 항원 제시, MHC class I과 II에 의한 항원제시, apoptosis 및 이후의 항체 생산이 정상적으로 이루어져 폐사가 발생하지 않는 것으로 생각되었다. 그러나 폐사가 발생하는 $15^{\circ}C$에서는 MHC class I매개의 항원 제시와 탐식 작용등의 선천 면역은 이루어지나 macrophage에 의한 MHC class II매개의 항원 제시와 apoptosis저하, 항체 생산 관련 유전자의 발현저하가 관찰되어 초기 macrophage에 의한 항원제시의 실패로 적응 면역이 제대로 활성화되지 않아 폐사가 발생한 것으로 사료된다.

• 한국어류학회지
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• 제11권2호
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• pp.134-138
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• 1999

피부흡충인 Entobdella hippoglossi가 숙주인 Atlantic halibut의 피부에 기생할 때 기생 부위별 밀도와 숙주의 피부 점액세포 밀도를 조사하여 E. hippoglossi의 기생이 피부점액 세포의 밀도와 관계가 있는가를 조사하였다. 숙주인 Atlantic halibut 복측과 배측에 기생하는 E. hippoglossi의 밀도는 비슷하였으나 기생충의 크기는 복측이 배측보다 더 컸으며, 배측내에서는 배측의 머리부분에 기생하는 E. hippoglossi의 밀도가 배측의 중앙부나 꼬리부분에서보다 높았다. 숙주의 점액세포 크기, 밀도 그리고 표피 점액층의 두께는 대체로 기생충의 밀도와 비례하였고, 숙주내에서 기생충의 선택적 기생은 점액세포의 밀도와 관계가 있었다.

• Genomics & Informatics
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• 제20권3호
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• pp.33.1-33.17
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• 2022

Nervous necrosis virus (NNV) is a deadly infectious disease that affects several fish species. It has been found that the NNV utilizes grouper heat shock cognate protein 70 (GHSC70) to enter the host cell. Thus, blocking the virus entry by targeting the responsible protein can protect the fishes from disease. The main objective of the study was to evaluate the inhibitory potentiality of 70 compounds of Azadirachta indica (Neem plant) which has been reported to show potential antiviral activity against various pathogens, but activity against the NNV has not yet been reported. The binding affinity of 70 compounds was calculated against the GHSC70 with the docking and molecular dynamics (MD) simulation approaches. Both the docking and MD methods predict 4 (PubChem CID: 14492795, 10134, 5280863, and 11119228) inhibitory compounds that bind strongly with the GHSC70 protein with a binding affinity of -9.7, -9.5, -9.1, and -9.0 kcal/mol, respectively. Also, the ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties of the compounds confirmed the drug-likeness properties. As a result of the investigation, it may be inferred that Neem plant compounds may act as significant inhibitors of viral entry into the host cell. More in-vitro testing is needed to establish their effectiveness.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 1992년도 학술강연회
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• pp.7-19
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• 1992

Fish pathology is one of the main scientific bases upon which this expansion in aquaculture has been dependent and requires a wide knowledge of the environmental constraints, the physiology and characteristics of the various pathogens, the responses of the host and the methods by which they may be controlled. The primary disease and parasite problems in aquaculture animals relate to viral, bacterial, fungal and protozoan epizootics. Parasitic nematodes, trematodes and cestodes are commonly found in aquaculture animals, but seldom are they present in concentrations sufficinet to cause significant problems. When an epizootic does occur and chemical treatment is indicated, the appropriate chemical must be selected and properly applied. We have antibiotics, sulfa, nitrofuran and other chemicals for treatment of fish diseases. Some may be mixed with the fred during formulation, added to the pellets of feed as a surface coating, given in the dorm of an injection or used as a bath. Even though a drug or chemical has been officially approved for use in aquaculture, the substance should never be used unless there is a clear need. Some of the reasions for this view are as follows: (1) the constant use of antibiotics can lead to the development of resistant strains of bacteria, (2) biofilter efficiency may be impaired or destroyed by chemicals added to closed recirculating water systems, and (3) the injudicious use of chemicals can have a damaging effect on the environment as well as on human.

• 한국수산과학회지
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• 제43권4호
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• pp.307-313
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• 2010

Stanniocalcin 1 (STC1) is a glycoprotein hormone that is important in the maintenance of calcium and phosphate homeostasis in both fish and mammals. STC1 and its paralog STC2 are expressed in multiple tissues in fishes, although the physiological roles of piscine STCs are still unclear compared with those of mammals. In this study, we cloned olive flounder STC1 (ofSTC1) and ofSTC2 cDNAs into pET28a vector and used E. coli Rosetta (DE3) as the host strain for protein expression. Expression experiments were carried out using isopropyl-$\beta$-D-thiogalactoside (IPTG) and nickel affinity chromatography. We could identify the recombinant proteins as single 29.5 kDa (ofSTC1) and 33.2 kDa (ofSTC2) bands in the insoluble fraction on sodium dodecyl sulfate- polyacrylamide gel electrophoresis (SDS-PAGE). These results indicate that ofSTC1 and ofSTC2 were expressed as insoluble proteins in E. coli. Furthermore, the injection of ofSTC1 protein into juvenile tilapia resulted in a decrease of the serum calcium level. These results suggest that the purified fish STC1 and STC2 proteins may be used to elucidate the physiological role of STCs in fishes.

• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.537-541
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• 2016

Stellantchasmus falcatus (Digenea: Heterophyidae) is first reported from Cambodia through recovery of the metacercariae from mullet fish and adult flukes from an experimentally infected hamster. We purchased 7 mullets, Chelon macrolepis, in a local market of Phnom Penh, Cambodia, and each of them was examined by the artificial digestion method on May 2010. The metacercariae of S. falcatus were detected in all mullets (100%) examined, and their average density was 177 per fish. They were elliptical, $220{\times}168{\mu}m$ in average size. They were orally infected to an hamster to obtain adult flukes. Adults recovered at day 10 post infection were observed with a light microscope and a scanning electron microscope (SEM). They were small, $450{\times}237{\mu}m$ in average size, had a small oral sucker ($41{\times}50{\mu}m$), subglobular pharynx ($29{\times}21{\mu}m$), slender esophagus ($57{\mu}m$), long and thick-walled expulsor ($119{\times}32{\mu}m$), spherical ovary ($58{\times}69{\mu}m$), and 2 ovoid testes (right: $117{\times}74{\mu}m$; left: $114{\times}63{\mu}m$). Eggs were small, yellow, and $23{\times}12{\mu}m$ in average size. In SEM observations, tegumental spines were densely distributed on the whole tegument, and single small type I sensory papillae were distributed around the lip of oral sucker. The small ventral sucker was dextrally located and had 8 type I sensory papillae on the left margin. It has been first confirmed in the present study that the mullet, C. macrolepis, is playing the role of a second intermediate host of S. falcatus in Cambodia.

• 한국어병학회지
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• 제11권2호
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• pp.137-141
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• 1998

TSB 해수배지와 숙주로서 L. garvieae No. 44를 배양조건으로 사용한 경우, L. garvieae 111균주중 용원화되었다고 추정되어진 96균주의 cells에서 temperate Phage가 효과적으로 분리되었다. 하지만 동일한 배양조건에서 보통의 TSB 배지를 사용한 경우에서는 temperate phage는 전혀 나타나지 않았다. 이 temperate phages는 TSB 해수배지와 ultraviolet irradiation를 병용한 경우 역시 효과적으로 분리되었다. 분리된 모든 temperate Phages는 기존의 phage(PLgY, PLgW, PLgS) 의 lytic nature와는 달리 오직 L.garvieae No. 44만을 lysis하였다. 배양후 약 1시간후 phage가 나타났으며 12시간 후 virulent phage의 최고농도($10^{10}$ PFU/ml) 보다 훨씬 낮은 농도인 $10^6$ PFU/ml까지 증가하였다.

• 한국어병학회지
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• 제18권3호
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• pp.197-204
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• 2005

우리나라산 해산 복족류에 기생하는 흡충류의 유미자충의 종류를 조사하여 기생종별 형태적 특징과 분류 list를 작성 할 목적으로 2004년 4월부터 2005년 2월까지 2개월마다 1회씩 서해안 금강하구의 내초도에서 해산 권패류인 댕가리를 채집하여 조사한 바, Pygidiopsis summus의 cercaria와 Cercaria pseudogranifera가 검출되었다.검출된 Pygidiopsis summus의 cercaria는 한국 미기록 종으로 기생률은 0.67-20.67%로 8월에 가장 높았고, 10월에 가장 낮았으며, 12월에는 기생패를 검출 할 수 없었다. 반면에 Cercaria pseudogranifera는 기생률이 9.3-74.0%로 간석지 온도가 16$^{\circ}C$인 12월에 가장 높았다.양종의 cercaria가 기생된 댕가리는 이들 기생흡충류의 중간숙주로 새로이 추가된다.

• 한국어병학회지
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• 제22권3호
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• pp.239-251
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• 2009

배양 온도, 배양 배지 중의 pH, NaCl 농도, iron 농도와 같은 배양 조건이 P. damselae의 미생물학적 성상 및 병원성에 미치는 영향을 조사하였다. P. damselae는 배양 온도 15-30${^{\circ}C}$에서 배지의 pH 5-9, NaCl 농도 0-6%와 $FeCl_{3}$ 첨가시 성장이 촉진되었지만, iron-chelator 첨가 시성장이 억제되었다. Iron-limited 조건에서 배양시 ECPs protein 농도, phospholipase, 용혈능, siderophore 및 cytotoxicity 활성 이 높게 나타났고, 넙치 혈청의 살균작용 대한 생존율도 증가 되었으나, iron-added 조건에서는 감소되어, 배양 조건 중 iron 농도에 영향을 가장 많이 받는 것으로 나타났다. 따라서, 본 연구에서 적용한 iron-limited 조건은 철농도가 낮은 숙주 내와 유사한 환경이므로 iron-limited에서 P. damselae 배양 시 나타나는 병원성의 증가는 어체에 감염시 나타나는 병원성 발현 기전과 유사할 것으로 사료된다.

• 한국어병학회지
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• 제23권3호
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• pp.313-322
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• 2010

Edible tunicate Halocynthia roretzi, one of the most commercially important aquatic organisms in Korea, has been killed by tunic softness syndrome since last decade. The intracellular protistan parasite observed by the transmission electron microscope in hemocytes of the tunicate was considered to be the causative agent of the mass mortality. The goal of the present work is to examine the characteristic features of the parasite by identifying the 18S rDNA sequences of the parasite. The experiments conducted include amplification of presumptive 18S rDNA from diseased tunicate tissues with UNonMet-PCR and sequencing the product. A preliminary phylogenetic analysis was performed on the presumptive parasite rDNA. A digoxigenin labeled DNA probe was designed on the basis of the sequences of rDNA. Dig-ISH assay was conducted to diagnose the protistan parasite. A PCR using UNonMet-PCR primer generated 595 bp SSU rDNA fragment. Subsequently, PCRs with primer pair expended this sequence to 1542 bp. This is the first partial sequences of SSU rDNA gene to be published on the protistan parasite that has presumed causing the mass mortality of tunicate. Since the Dig-ISH technique demonstrated the presence of infection in hemocytes on the all host tissues, the fragment was confirmed to be the intracellular protistan parasite SSU rDNA. A phylogenetic analysis suggested that the protistan parasite may be a unique eukaryote that is closely related to Apicomplexa.