• Journal of the korean veterinary medical association
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• v.17 no.6
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• pp.52-55
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• 1981

현재까지도 본질병의 원인체인 Eperythozoon에 대한 생활환 감염경로 및 매체등 역학적인 연구가 되어 있지 않은 상태이다. 더욱이 우리나라에서는 본증의 연구 조사가 거의 전국적 규모에서 이루어져 있지 않은 실정인데, 본인등이 건강돈으로 도살되는 성돈에서 $72\%$의 자연 감염율을 관찰할 수 있었으며, 대단위 양돈장에서 높은 자돈의 치사율을 보이는 본증의 유행상을 경험한 점을 감안할때 앞으로 우리나라에서 효과적인 양돈사업의 육성을 위해서 본질병에 대하여 더욱 관심과 연구를 집중해야 될 줄 믿는다. 또한 본 원인균은 일반 전염병 치료제로 많이 애용되는 Sulfa제나 항생제에 대하여 전혀 감수성이 없으며 매독성이 비소제인 Arsphenamine만이 특효가 있다. 점도 임상수의사들이 관심을 기울여야 할 사항이면, 보다 저독성이며 효과적인 치료제 개발도 시급히 요구되는 실정이라 하겠다.

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.225-230
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• 1995

The first human case of Diplogonoporus balaenoperae infection is reported in Korea. The pattent was a 41-year old male who passed a part of cestode strobila, about 1m long, spontaneously in his stool. He used to eat raw marine fish when he drank alcohol. The Worm was identified as D. balaenopterae after morhological observations and literature reveiw. Results of laboratory examination were within normal limits except for slight eosinophilia (6%) and extraordinarily high serum Ig E level (10, 182 IU/ml).

• Korean journal of applied entomology
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• v.26 no.1 s.70
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• pp.37-41
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• 1987

Sporulation potential and conidia release phase of Pyricularia oryzae on lesions under the natural conditions were measured in 1985 and 1986 leaf blast seasons. The amount of conidia produced in lesions on detached leaves and conidia released under the field condition were reached peak at $5{\sim}7$ days after lesion appearance. The maximum numbers of conidia produced and released were 16,200 and 15,900, respectively. Conidia release under the natural conditions lasted for 30 days.

• The Korean Journal of Mycology
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• v.45 no.3
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• pp.188-195
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• 2017

Despite the high commercial value of the pine mushroom (Tricholoma matsutake) around the world, its production still depends upon natural harvesting. In recent years, mushroom researchers in Korea and Japan have been successful in artificially cultivating T. matsutake by producing single mushroom through matsutake-infected pine seedlings. In this study, we determined the minimum seedling height required for the survival of matsutake mycelia in the infected pine seedlings in the field. The survival rate of matsutake mycelia in the matsutake-infected pine seedlings was 50% (14) in two years and 71% (10) in one year after their transplantation. The average height at time of transplantation of the matsutake-infected pine seedlings that bore surviving mycelia after transplantation was 25 cm (minimum 12 cm to maximum 40 cm). In conclusion, the matsutake mycelium of matsutake-infected pine seedlings was able to survive in field conditions if the height of the seedling at the time of T. matsutake infection was at least 12 cm. These results suggest that the height of the host plants used in conventional matsutake-infected pine seedling production should be greatly reduced to improve the matsutake cultivation. Therefore, standardization of the seedling height for artificial cultivation of pine mushrooms by the matsutake-infected pine seedling method is suggested.

• Journal of Life Science
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• v.20 no.9
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• pp.1294-1298
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• 2010

White spot syndrome virus (WSSV) is one of the most virulent viral agents threatening the penaeid shrimp culture industry. This study was carried out to evaluate the susceptibility of the sand shrimp, Crangon affinis, to WSSV as an alternative experimental model. WSSV caused 100% mortality in C. affinis within 7 days after experimental infection by immersion. Based on challenge studies, it was confirmed that C. affinis could be a potential host in WSSV transmission. Also, the neutralization of WSSV was carried out using an antiserum raised against recombinant envelop protein rVP466 to evaluate the WSSV infection mechanism. A constant amount of WSSV (at $1{\times}10^4$ diluted stocks) was incubated with various amounts of antiserum and then mixed to 20 l reservoir for the immersion challenge of C. affinis for neutralization. At 5 days post challenge, the shrimp in the positive control immersed in the immersion reservoir containing WSSV stock showed 100% mortality. The shrimps challenged with the 3 different mixtures of WSSV and rVP466 antiserum (1:0.1, 1:0.5 and 1:1) showed 100%, 68.8% and 68.8% mortality at 14 days post challenge, respectively. These results indicated that the antiserum raised against rVP466 could block WSSV infection in C. affinis. Therefore, this study confirmed that C. affinis can be naturally infected by WSSV as another potential host and that C. affinis can be used as an alternative experimental animal instead of penaeid shrimps.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.134-139
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• 2010

Mycobacterium tuberculosis (Mtb) is one of the most successful pathogens to infect one third of world population. Th1-mediated immunity against Mtb infection is known as critical to express mycobacteriostatic function but it is not sufficient to resolve the infection. In this study, to verify the possibility Mtb itself change the gene expression to survive against host immune response, expression pattern of selected H37Rv genes, 16S rRNA, acr, fbpA, aceA, and ahpC, during the course of infection was measured with absolute quantitation method using real-time RT-PCR. The total number of transcripts of 16S rRNA increased during the course of infection, which was coincide with the increasing CFU. The total number of fbpA transcripts per CFU, which encode typical secreted Mtb antigen, Ag85A, increased for 10 days of infection before decreasing. The number of transcripts of acr per CFU, which encode heat shock protein, ${\alpha}$-crystallin, increased during the infection, and ahpC and aceA, they both are enzymes produced in oxidative stressful condition, increased for 20 days and then slightly decreased on day 30. These findings are one of survival strategy of pathogen evading host immune response lead to persistent infection inside host cells.

• Research in Plant Disease
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• v.16 no.2
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• pp.109-114
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• 2010

The occurrence factors of Rice stripe virus (RSV) in Chungcheongbukdo were analyzed by investigating the viruliferous insect rate (VIR) of overwintered small brown plant hopper (SBPH), the population density of SBPH, the infection rate of natural host plants, and the occurrence rate of RSV on rice paddy fields at the 3 areas of Cheongwon, Jincheon, and Boeun in 2008 and 2009. The average VIR of overwintered SBPH was 0.0% in 2008 and 1.1% in 2009. From SBPH collected on early June in 2009, VIR was higher as 1.4% at Jincheon and 4.2% at Boeun than those of overwintered SBPH, and this higher VIR might relate stronlgy with the adult population of SBPH immigrated from China. The populations of SBPH at Cheongwon, Jincheon and Boeun in 2008 were 3.8, 7.5 and 20.8 Head/$m^2$, respectively. However, those of Cheongwon and Jincheon increased up to about two folds as 8.4 and 13.1 in 2009. No RSV was detected on the natural host plants including barley. The factors involved in RSV occurrence were affected negatively by the low VIR of overwintered SBPH, the low population of overwintered SBPH, the low infection rate of RSV on the natural host plants, and the clean cultivation environment in Chungcheongbukdo.

• Journal of fish pathology
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• v.19 no.3
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• pp.197-206
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• 2006

The distribution of iridoviruses in five freshwater ornamental fishes, pearl gourami (Trichogaster leeri), dwarf gourami (Colisa lalia), silver gourami (Trichogaster microlepis), blue gourami (Trichogaster trichopterus sumatranus) and freshwater angelfish (Pterophyllum scalare), imported from Singapore was examined in 2004 and 2005. The presence of iridoviruses in 56 sample groups was determined using PCR technique and showed PCR positive in 11 sample groups. The proportion of fish infected by iridovirus was differed depending upon species; 31.8% (7/22) for pearl gourami, 18.2% (2/11) for dwarf gourami, 16.7% (1/6) for blue gourami, 9.1% (1/11) for silver gourami and 0% (0/6) for angelfish. In quantitative comparison of viral DNAs isolated from infected tissues, the DNA concentration of iridovirus in pearl gourami was higher than that in dwarf gourami. Although pearl gourami infected naturally by iridovirus showed 100% mortality in keeping experiment for 3 weeks, only 57% of those was positive in PCR. In the comparison of nucleotide sequences of the PstⅠ fragment known as the most variable genomic region, both iridoviruses isolated from pearl gourami and dwarf gourami showed identity more than 99% with infectious spleen and kidney necrosis virus (ISKNV) isolated from mandarinfish (Siniperca chuatsi).

• 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.

• 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.