• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.181-194
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• 2002

Parasitism is a one-sided relationship between two organisms in which one benefits at the expense of the other. Parasitic dinoflagellates, particularly species of Amoebophrya, have long been thought to be a potential biological agent for controlling harmful algal bloom(HAB). Amoebophrya infections have been reported for over 40 species representing more than 24 dinoflagellate genera including a few toxic species. Parasitic dinoflagellates Amoebophrya spp. have a relatively simple life cycle consisting of an infective dispersal stage (dinospore), an intracellular growth stage(trophont), and an extracellular reproductive stage(vermiform). Biology of dinospores such as infectivity, survival, and ability to successfully infect host cells differs among dinoflagellate host-parasite systems. There are growing reports that Amoebophrya spp.(previously, collectively known as Amoebophrya ceratii) exhibit the strong host specificity and would be a species complex composed of several host-specific taxa, based on the marked differences in host-parasite biology, cross infection, and molecular genetic data. Dinoflagellates become reproductively incompetent and are eventually killed by the parasite once infected. During the infection cycle of the parasite, the infected host exhibits ecophysiologically different patterns from those of uninfected host in various ways. Photosynthetic performance in autotrophic dinoflagellates can be significantly altered following infection by parasitic dinoflagellate Amoebophrya, with the magnitude of the effects over the infection cycle of the parasite depending on the site of infection. Parasitism by the parasitic dinoflagellate Amoebophrya could have significant impacts on host behavior such as diel vertical migration. Parasitic dinoflagellates may not only stimulate rapid cycling of dissolved organic materials and/or trace metals but also would repackage the relatively large sized host biomass into a number of smaller dinospores, thereby leading to better retention of host's material and energy within the microbial loop. To better understand the roles of parasites in plankton ecology and harmful algal dynamics, further research on a variety of dinoflagellate host-parasite systems is needed.

• Parasites, Hosts and Diseases
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• v.33 no.4
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• pp.281-288
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• 1995

For the two-dimensional observation on the growth and development of CLonorchis sinensis, an image analysis system (IBAS 2000, Kontron, Germany) was used in this study. On 3, 6, 9, 12, 15, 21, 30 and 90 days of infection, 474 worms were collected from rats infected with 50 metacercariae each. The overall recovery rate was 31.6%. The worms grew rapidly in their length and width up to 30 days of infection and then, did slowly to 90 days of infection. However, the growth pattern of body area was not similar to that of body length and width, because the body area increased continuously even after 30 days of infection. With the image analysis system, the sizes of irregular-shaped genital organs were measured easily, which showed sigmoidal growth patterns . The growth rate of genital organs increased rapidly. until 21 days of infection when the uterus was filled with numerous eggs, and then gradually slowed down to 90 days. There was no difference in growth pattern between the anterior and posterior testis. The seminal receptacle , however, showed an abrupt increase in size between 15 to 21 days of infection when it was filled with condensed semen. Therefore, the growth pattern of seminal receptacle might be used as another criteria to estimate the extent of sexual maturation of C. sinensis. From this study, it is suggested that image analysis system is very useful to reveal the growth and development pattern of C. sinensis, especially of their internal organs.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.1
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• pp.34-38
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• 2012

호산구는 염증 반응에 의해 활성화되며, 주로 기생충 감염이나 알러지 질환 등에 대한 면역 작용을 담당한다고 알려져 있다. 호산구 증가증은 약물 반응, 알러지, 국소적인 기생충 감염 등에 의한 경우가 많지만, 자가면역성 질환이나 종양에 의한 경우도 있다. 최근 연구를 통해 위염의 대표적인 원인균 중 하나인 유문나선균 역시 위점막에서 나타나는 조직 호산구 증가증의 원인이 될 수 있다고 밝혀지고 있으나, 유문나선균에 의한 호산구 증가증 발생 기전이나 빈도는 아직까지 확립되지 않고 있다. 위점막 내 호산구 침윤과 동반되는 위염은 복통, 오심, 구토, 설사, 장폐색 등을 일으킬 뿐만 아니라, 아토피성 피부염, 천식, 위식도 역류, 염증성 장질환 등의 발생과 관련이 있다고 보고되고 있다. 위염 및 다양한 관련 질환에 의한 증상은 공중 근무자들의 임무 수행 능력을 저하시켜 항공기 사고를 발생시킬 수 있는 가능성을 가지고 있다는 점에서 항공의학적으로 매우 중요하며, 실제로 호산구성 위염이나 유문나선균 감염의 치료 여부가 공중 근무자에게 일시적 또는 영구적 비행임무정지를 부과할 수 있는 기준이 되기도 한다. 본 연구에서는 대한민국 공군 장병 환자를 대상으로 내시경을 통해 얻은 위점막 조직 내 호산구수를 측정하고, 이를 위점막 표면의 유문나선균 존재 유무와 관련지어 보았다. 111명 중 20명의 환자에서 한 고배율 시야 당 30개 이상의 호산구가 관찰되었고, 63명의 환자의 위점막 표면에서 유문나선균을 확인하였다. 또한 위점막 내 호산구의 밀도와 유문나선균의 존재 간의 관계는 통계학적으로 유의하였다. 본 연구의 결과는 대한민국 공군 장병을 대상으로 하여 조직 호산구 증가증과 유문나선균의 빈도 및 상호 관계를 최초로 분석했다는 점에서 의의가 있으며, 추후 유문나선균이 어떤 기전으로 위점막 조직 내 호산구의 증가에 관여하는지에 대한 연구를 진행하기 위한 기초 자료로서 활용될 수 있을 것이다.

• Korean Journal of Poultry Science
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• v.38 no.1
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• pp.13-19
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• 2011

In January 2010, high mortalities of ducklings occurred in two adjacent farms. Ducklings in farm A showed neurologic signs including paddling, opisthotonus and lameness, but ducklings from farm B had no specific clinical signs. At post mortem, diffused hemorrhagic spots in the liver and hemorrhages in the small intestine were observed in ducklings from farm A, and ducklings from farm B had only proventricular ulceration. Microscopically, multiple necrosis of hepatocytes, hyperplasia of the bile ducts, hemorrhages, infiltration of lymphocytes and bacterial colonies were commonly observed in the liver of ducklings from both farms. Also, type A and C duck hepatitis virus (DHV) were isolated from farm A and farm B, respectively and Salmonella typhimurium was commonly isolated and identified serologically and biochemically. To our knowledge, this is the first report about the co-infection of DHV and Salmonella typhimurium in ducklings, and co-circulation of type A and C duck hepatitis viruses in Korea.

• Food Science and Industry
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• v.55 no.3
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• pp.276-283
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• 2022

Vitamin D is a fat-soluble vitamin helps to retain calcium and phosphorus but also has shown to affect immune regulation and homeostasis. In humans, vitamin D3 and vitamin D2 and their metabolite has intensively studied in both innate and adaptive immune system that they are important to regulate overwhelmed inflammation. The vitamin D receptor is a nuclear hormone receptor which regulate various downstream target gene expressions as a transcription factor related to metabolism, immune regulation, etc. Vitamin D deficiency is a high-risk factor for inflammatory diseases like autoimmune disease and allergy. In addition, reduced vitamin D seem to correlate with susceptibility to the virus infection such as HIV and COVID-19. In this review, we will summarize up-to-date vitamin D's role in various immune cells, immune regulatory functions during autoimmune, allergic, and infectious diseases. We will also discuss about vitamin D supplement effects in human trial studies for COVID-19.

• Pediatric Infection and Vaccine
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• v.4 no.2
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• pp.308-313
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• 1997

Ceftriaxone, an effective third generation cephalosporin with a wide range of antimicrobial activity, has become widely used by pediatricians for a variety of bacterial infections including meningitis. It has been associated with the development of sludge or stone in the gallbladder of some patients treated with this drug. Ceftriaxone associated biliary sludge has unusual acoustic characteristics and resembles gallstone. The sludge can cause symptoms such as cramping abdominal pain, and disappears after stopping ceftriaxone administration. Because of these seemingly confusing observations, it is important for the clinicians to recognize these findings that ceftriaxone treatment can cause. We report a case of ceftriaxone associated biliary sludge in Korean children. A 6-year-old girl who was treated for meningitis with ceftriaxone (100mg/kg/day) developed cramping upper abdominal pain from 5th hospital day. Physical examination, liver function tests and X-ray revealed no specific abnormal findings. But abdominal ultrasound revealed high amplitude echogenic sludge with prominent post-acoustic shadow in gallbladder and its diameter was 1.5cm. We stopped ceftriaxone administration and tried conservative care. Abdominal cramping pain subsided after 3 days of ceftriaxone removal. Second abdominal ultrasound confirmed the disappearance of sludge at 3 weeks later.

• Journal of the Korean Society of Radiology
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• v.82 no.4
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• pp.826-837
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• 2021

Immunoglobulin G4-related disease (IgG4-RD) is a chronic inflammatory condition involving multiple organs, including the salivary or lacrimal glands, orbit, pancreas, bile duct, liver, kidney, retroperitoneum, aorta, lung, and lymph nodes. It is histologically characterized by tissue infiltration with lymphocytes and IgG4-secreting plasma cells, storiform fibrosis, and obliterative phlebitis. In the thoracic involvement of IgG4-RD, mediastinal lymphadenopathy and perilymphangitic interstitial thickening of the lung are the most common findings. Peribronchovascular and septal thickening and paravertebral band-like soft tissue are characteristic findings of IgG4-RD. Other findings include pulmonary nodules or masses, ground-glass opacity, alveolar interstitial thickening, pleural effusion or thickening, mass in the chest wall or mediastinum, and arteritis involving the aorta and coronary artery. Radiologic differential diagnosis of various malignancies, infections, and inflammatory conditions is needed. In this review, we describe the imaging findings of IgG4-RD and the radiologic differential diagnoses in the thorax.

• Korean Journal of Poultry Science
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• v.12 no.2
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• pp.135-143
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• 1985

A total of eight strains of avian reoviruses were isolated from chickens with arthritis or stunted growth. The isolations were made from broilers or broiler breeders under 12 weeks of age. The viruses had a typical morphology of reoviruses with double capsid layers and 81nm of diameter. In agar gel precipitation tests, the isolates reacted with antisera prepared against S-1133 or R-1 strains of avian reoviruses and cross reacted with S-1133 antigen. They did not agglutinated RBC's from day-old chicks, adult chickens, guinea pigs, and horses. The isolates showed strong resistance against the treatments of chloroform, IUdR, and heat, When infectivities of the viruses were titrated in cell cultures of chicken embryo fibroblast, chicken embryo liver, and Vero cells, similar end points reached four to five days after inoculation, regardless of tell types and virus inoculation time, either inoculated simultaneously at the time of cell seeding or on confluency. Mean times of mortality of chicken embryos inoculated with the isolates via the chorioallantoic membrane ranged from 54 to 59 hours and that of S-1133 strain was 73 hours.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.271-276
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• 2006

Previously we demonstrated that virus-inducible stress protein (VISP) is induced in fish cells by the infection of a fish rhabdovirus. In this paper, we investigated the subcellular localization of the VISP and determined the region of VISP responsible for the subcellular localization. The CHSE-214 cells were stained with monoclonal antibody raised against VISP and observed with confocal microscope to detect the endogenous VISP. The results showed that the VISP localizes to the perinuclear region as spots. A plasmid expressing VISP fused to enhanced green fluorescent protein (EGFP) was constructed. The transient expression of full-length VISP fused to EGFP in CHSE-214 cells confirmed the spot formation of the VISP at perinuclear region. To determine the region responsible for the perinuclear localization of the VISP, we constructed a series of deletion mutants and, by using these deletion mutants, we found that C-terminal region of the VISP (aa 612-710) is essential for the perinuclear distribution of VISP and that this region contained nuclear receptor binding motif (691-TLTSLLL-697). Our results suggest that VISP localizes to the perinuclear region and C-terminal regions are important for this localization. Further studies on the role of the perinuclear localization of VISP in IHNV growth mali reveal the novel mechanism of IHNV pathogenecity.

• The Korean Journal of Cytopathology
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• v.4 no.2
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• pp.176-180
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• 1993

Clonorchiasis is common in Korea. The coinfection of amebic abscess with clonorchiasis is not rare in endemic areas. The coinfection may influence on its manifestations each other. We experienced a human case with unusal manifestation of amebic liver abscess associated with coinfection by Clonorchisis sinensis. The case was an 80-year-old female. She lived in Yongil-gun, Kyongsangbuk-do, Korea, She had multiple amebic abscess cavities in the liver, one of which subsided spontaneously and others newly appeared. She was diagnosed by CT guided aspiration of the cyst, which revealed trophozoites of ameba and eggs of C. sinensis. She was treated with praziquantel and metronidazale and was cured.