• The Science & Technology
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• v.30 no.6 s.337
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• pp.82-82
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• 1997

생물계에서는 기생충이 숙주의 행동과 생리를 바꾸는 현상이 많이 일어난다. 숙주의 생식에 영향을 미치는 '기생거세'라는 것이 있으니 생식소가 기생충의 칩입을 받아 생식능력을 잃거나 성전환을 하는 등 기이한 현상을 볼 수 있다.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.233-240
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• 1991

A female Brachymeria lasus (Walker) was exposed to one or four pupae of host Hyphantria cunea Drury for 20 minutes within a petri dish $(1.5\times9cm)$ to learn factors influencing the host discrimination by the parasitoid. It rejected the parasitized host with its rejection ratio 73.3% for the one pupal exposure vs 100% for the four pupal exposure scheme. The parasitoid could discriminate the parasitized host by its antennal drumming and ovipositor probing due to a pheromone-like external marking which is effective only for a certain peiod of time, and a host quality associated with the parasitoid development, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.4
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• pp.2221-2221
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• 2002

The first laboratory culture of host-parasite system of Prorocentrum minimum- Amoebophrya sp. was established by single cell isolation method. Here, we report the life cycle stages of the parasitic dinoflagellate. Amoebophrya sp. of the red tide dinoflagellate P. minimum as observed by light and epifluorescence microscopy. Infections developed inside the nucleus of P. minimum. The trophont developed to occupy almost all the intracellular space of the host at its late stage. The fully developed trophont finally ruptured through the host cell. “Vermiform stage”, the free-swimming extracellular lift cycle stage is followed by another stage for the sudden release of many individual dinospores. Our laboratory strain of the host-parasite system for P. minimum, a causative species fur the huge red tides in spring and summer in Korean coastal waters, could be a useful living material for the in situ biological control of harmful algal blooms.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.4
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• pp.221-225
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• 2002

The first laboratory culture of host-parasite system of Prorocentrum minimum- Amoebophrya sp. was established by single cell isolation method. Here, we report the life cycle stages of the parasitic dinoflagellate. Amoebophrya sp. of the red tide dinoflagellate P. minimum as observed by light and epifluorescence microscopy. Infections developed inside the nucleus of P. minimum. The trophont developed to occupy almost all the intracellular space of the host at its late stage. The fully developed trophont finally ruptured through the host cell. “Vermiform stage”, the free-swimming extracellular lift cycle stage is followed by another stage for the sudden release of many individual dinospores. Our laboratory strain of the host-parasite system for P. minimum, a causative species fur the huge red tides in spring and summer in Korean coastal waters, could be a useful living material for the in situ biological control of harmful algal blooms.

• 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.

• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.134-138
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• 1999

This study investigated the relationship between attachment site preference of the skin parasite, Entobdella hippoglossi and mucous cell density, moucus cell size and epidermis thickness on the surface of the Atlantic halibut Hippoglossus hippoglossus. Parasites occupying the ventral surface of their host were significantly longer and wider than those found on the other zones of the fish (P<0.05). The mean size of the mucous cells on the front region was significantly greater than the other regions on the dorsal and ventral surface (P<0.05). The average numbers of mucous cells and the epidermal thickness in the skin of the halibut were shown that the front region had significantly higher numbers of mucous cells and thicker layer than the rear region on the dorsal and ventral surface of the halibut, respectively (P<0.05).

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.223-228
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• 2002

The infection of parasites causes all kinds of parasitosis. The parasites that causes ophthalmic diseases are Protozoa, Nematodes, Cestodes and so on. These parasites has specific connection chains in between parasite and vector, parasite and host, host and host. If these connection chains were polluted or exposed into the worsened environments, the parasite are infected into human body which is its host. The parasite causes the destroy of organic tissues or inflammation and allergic responses by its toxicity and resistance of the host. In worst case, it might cause blindness. In order to prevent these disease, we should keep the clean and clear living environment of every human being.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.99-105
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• 2002

A gregarious pupal endoparasitoid Tetrastichsus sp. (Hymenoptera: Eulophidae) was reared in vitro from oviposition to adult emergence on an artificial host. The host pupal case was made using 0.02 mm-thick polypropylene film, and was filled with a diet consisting of powders of Antheraea pernyi pupa, chicken yolk, infant formula, royal jelly, and Neisenheimer's salt solution. Female parasitoids reared in the artificial host produced smaller sized progeny than those reared in in vivo, but the adults reproduced fertile offsprings. Furthermore in vitro second-generation (G$_2$) females showed more improved biological characteristics, compared with their parents. The fecundity (mean no. adult progeny), oviposition period (days), and longevity (days) of G$_2$ female were evaluated as 45.7, 7.8, and 13.8, respectively Female biased sex ratio was obtained with 76.9% female progeny. The results demonstrated that Tetrastichus sp. is a promising parasitoid for in vitro mass production.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.4
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• pp.359-369
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• 2007

Amoebophrya is an obligate endoparasitic eukaryotic dinoflagellate infecting host species and eventually killing them within a short period. Because of its host specificity and significant impacts on population dynamics of host species, it has long been proposed to be a potential biological agent for controlling harmful algal bloom (HAB). For several decades, the difficulties of culturing host - parasite systems have been a great obstacle to further research on the biology of Amoebophrya but recent success of several culture systems reactivates this research field. In this study, as a preliminary work for understanding the impacts of Amoebophrya on the population dynamics of host species, semimonthly occurrence of infected host dinoflagellates by Amoebophrya spp. had been observed in Jinhae Bay for two years and with a host - parasite system cultivated, host specificity of Amoebophrya spp. on several dinoflagellates was tested. Amoebophrya spp. were observed in the cellular organelle and cytoplasm of several species including Akashiwo sanguinea, Ceratium fusus, Dinophysis acuminata, Heterocapsa triquetra, Oblea sp., Prorocentrum minimum, P. triestinum, Scrippsiella spinifera, and S. trochoidea. Among them two host - parasite systems for an athecate dinoflagellate, A. sanguinea, and for a thecate dinoflagellate, H. triquetra, had been able to be successfully established as laboratary cultures. Cross-infection tests for 6 species of dinoflagellates in which Amoebophrya was observed or had been reported to exist confirmed high preference for host species of the parasite. Through the continuous research on Amoebophrya occurring in Korean coastal waters, we need to maintain various host - parasite culture systems, which will be very helpful for understanding its ecological role in marine food webs and for applying the species to biologically control harmful algal blooms.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.13-19
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• 2012

To determine the status of Korean molluscs infection and relation with climate change of Korean peninsula, references were reviewed. Wild animals serve as intermediate, reservoirs and paratenic hosts to zoonotic parasites of human beings. Trematode are common parasites of molluscs and almost all trematodes infect mollusks as the first host in the life cycle, and most have a complex life cycle involving other hosts. The significance of auxiliary hosts to the ecology of the parasite has not been proper discussion. There is increasing concern as to the impact of climate change on the epidermiology of many parasitic diseases. A total of 21 species for snail transmitted parasites from Korean molluscs has been reviewed. Among them, 15 species was aquatic mollusks and 6 species for marine mollusks. Maximum infections belonged to Semisulcospira livertina had 11 kind of parasite pathogenic organisms, including Paragonimus westermani, Metagonimus yokogawai, Centrocestus armatus, Notocotylus magniovatus, Centrocestus formosanus, incerte cercaria, nipponensis cercaria, Yoshidae cercaria, cristata cercaria, innominatum cercaria and Metagonimus sp. And 11 in Parafossarulus manchouricus including Clonorchis sinensis, Asymphylodora japonica, Cyathocotyle orientalis, Exorchis oviformis, Notocotylus attenuatus, Echinochasmus japonicus, Loxogenes liberum, Cercariae of Loxogenes liberum Type I, Cercariae of Loxogenes liberum Type II, Furcocercus cercariae (Family Sanguincolidae) and Cercaria of Mucobucaris, 10 in Semisulcospira sp. including Paragonimus westermani, Metagonimus yokogawai, Centrocestus armatus, Echinochasmus redioduplicatus, Notocotylus magniovatus, Cercaria incerte, Cercaria nipponensis, Cercaria yoshidae, paludinarum cercaria and Metagonimus sp., 7 in Koreanomelania globus including Pseudexorchis major, Cercaria of parapleurolophocercous type, Metagonimus sp. (A & B), Cercaria nipponensis, Cercaria inserta and Cercaria yoshidae. Also, Tapes philippinarum have 3 pathogenic organisms including Cercariae tapidis, Cercariae furcocercus and Parvatrema sp. In particular, under climatic extremes such as floods and drought, aquatic molluscs may play a more prominent role in parasite transmission in the future.