• Parasites, Hosts and Diseases
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• 제39권1호
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• pp.31-41
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• 2001

The intestinal histopathology and in situ postures of Gymnophalloides seoi (Digenea: Gymnophallidae) were studied using C3H/HeN and C57BL/6 mice as experimental hosts; the effects of immunosuppression were also observed. The metacercariae isolated from naturally infected oysters, 300 or 1,000 in number, were infected orally to each mouse, and the mice were killed at days 3-21 post-infection (PI). In immunocompetent (IC) mice, only a small number of flukes were found in the mucosa of the duodenum and jejunum during days 3-7 PI, with their large oral suckers pinching and sucking the root of villi. The intestinal mucosa showed mild villous atrophy crypt hyperplasia, and inflammations in the villous stroma and crypt, with remarkable goblet cell hyperplasia. These mucosal changes were almost restored after days 14-21 PI. In immunosuppressed (IS) mice. displacement as well as complete loss of villi adjacent to the flukes was frequently encountered, otherwise the histopathology was generally mild, with minimal goblet cell hyperplasia. In these mice, numerous flukes were found, and it seemed that they were actively moving and rotating in situ. Several flukes were found to have invaded into the submucosa, almost facing the serosa. These results indicate that in IC mice the intestinal histopathology caused by G. seoi is generally mild, and the flukes do not penetrate beyond the mucosa, however, in IS mice. the flukes can cause severe destruction of neighboring villi. and some of them invade into the submucosa.

• Parasites, Hosts and Diseases
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• 제39권2호
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• pp.85-118
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• 2001

Studies on Gymnophalloides seoi (Digenea: Gymnophallidae) and human infections are briefly reviewed. This minute intestinal fluke was first discovered from a Korean woman suffering from acute pancreatitis and gastrointestinal troubles. It was described as a new species by Lee, Chai and Hong in 1993. The southwestern coastal village where the patient resided was found to be a highly endemic area, and additional endemic areas have been identified. The parasite is very small, 0.33-0.50 mm long and 0.23-0.33 mm wide. and characterized by the presence of a ventral pit. The first intermediate host remains unknown, but the second intermediate host has been found to be the oyster Crassostrea gigas. Man and the Palearctic oystercatcher Haematopus ostralegus have been shown to be natural definitive hosts , and wading birds including the Dentish plover Charadrius alexandrinus are highly susceptible to experimental infection. Gerbils, hamsters, cats, and several strains of mice were also susceptible laboratory hosts. In experimentally infected mice, the parasites inhabit the small intestine, pinching and sucking the root of villi with their large oral suckers, but they did not invade beyond the mucosa in immunocompetent mice. However, they were found to invade the submucosa in immunosuppressed mice. Human G. seoi infections have been found in at least 25 localities; 23 islands on the Yellow Sea or the South Sea, and 2 western coastal villages. The highest Prevalence was found in a village on Aphaedo. Shinan-fun (49% e99 Positive rate) : other areas showed 0.8-25.3% prevalence. Infected people complained of variable degrees of gastrointestinal troubles and indigestion. The infection can be diagnosed by recovery of eggs in the feces; however, an expert is needed to identify the eggs. Praziquantel, 10mg/kg in single dose, is effective for treatment of human infections. Eating raw oysters in endemic areas should be avoided.

• Parasites, Hosts and Diseases
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• 제23권2호
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• pp.203-213
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• 1985

요꼬가와흡충을 개에 감염시키고 장점 막에서 분리한 초기 발육단계의 충체가 특이한 자세를 취하고 있음을 관찰하여 이를 보고하고자 한다. 은어에서 분리한 요꼬가와흡충 피낭유충을 개 8마리에 각각 10,000개씩 경구감염시키고, 감염 후 3일, 9일, 4주 및 10주에 2마리씩 도살하였다. 105포르말린으로 고정한 장점 막에서 분리 수집한 요꼬가와흡충의 자세를 광학 및 주사현미경으로 관찰하였다. 그 결과를 요약하면 다음과 같다. 1. 충체회수율은 감염 3일에 42.6%, 9일에 55.0%, 4주에 33.2%, 및 10주에 8.9%로 감염이 경과할수록 감소하였다. 2. 감염후 3일된 개의 소장 점막의 조직절편에서 미성숙 충체가 융모사이에 위치하거나 장은와에 침입함을 관찰할 수 있었다. 이때 장은와 상부에 침입한 충체절편중에는 하부로 향한 충체 전반부가 2분지된 모양으로 절편이 발견되는 경우가 있었다. 3. 고정한 소장 조직에서 장점막을 분리하고 해부침으로 점막조직을 해부하여 수집한 고정된 충체는 특히 감염 후 3일째에 여러가지 특이한 자세를 보였다. 충체전반부가 앞쪽으로 매우 돌출한 충체가 많았는데 돌출한 형태는 단순히 한가닥으로 돌출한 것에서 2분지, 3분지된 것까지 있어 마치 충체 전반부가 아메바운동을 하는 것 같이 보였다. 4. 이러한 형태의 충체를 주사전자현미경으로 관찰하였던 바 돌출한 충체전반부는 돌출한 전반부의 길이를 따라 길이로 흠이 파져 있음이 관찰되 었다. 5. 감염후 9일, 4주 및 10주된 충체에서는 전반부가 돌출한 충체의 비율은 감염 3일된 충체에 비해 감소하였다. 이상의 결과에서 요꼬가와흡충은 감염초기에 장은와 선강(선륙) 상부에 충체 전반부를 밀어 넣을 때에 전반부를 튜브모양으로 만들어 침 입하며 인근 장은와 선강을 동시에 침 입하기 위하여 한 충체에서 여러개의 튜브모양 돌출부를 만들고 있는 것으로 사료되었다.터 그 다음 날 아침 6시까지 1시간 간격으로 모기를 채집하였다. C. tritaeniorhynchus의 활동이 가장 활발한 시간은 21시에서 22시, 24시에서 1시 사이였으며, 아침 5시 이후에는 한마리도 채집할 수 없었다. 조사 지역에서 채집한 유충은 사육실로 옮겨 종을 동정 하였던 바, 4층 14종이었으며, 매년 사회적으로 문제가 되는 뇌염 매개종인 C. tritaeniorhynchus의 유충서식처는 답, 옹덩이, 작은 연못, 늪, 미나리논 및 소택지 등이었다. 이상의 성적으로 미루어 보아 뇌염 매개 모기, C. tritaeniorhynchus는 6월 중순에 처음으로 출현하며, 8월 하순과 9월 초순에 최대 밀도를 나타내였고, 10월 중순 부터는 채집할 수 없음을 알았다.위분지 이상에서 3％로 자엽절 2분지의 비중이 특히 컸다.스 접종 8일 후의 중장원동세포내에서 A형 및 B형 봉입체가 형성되었음을 확인하였다. 10. FV감염 중장조직세포의 전자현미경 관찰에서는 바이러스 접종 5일 후에 배상세포의 'cytoplasmic wall'이 비대해지고 그 내부에 virus-specific vesicle이 형성되었으며, 바이러스 접종 8일 후에는 virus-specific vesicle, 바이러스 입자, linear structure, tubular structure 및 전자밀도가 높은 matrix 등의 바이러스 감염에 대한 특이적인 구조물이 배상세포의 세포질에서 관찰되었으며, microvilli내에서 바이러스 입자의 존재도 확정되었다. 특히 virus-specific vesicle 주위에서는 전자밀도가 높은 구형의 바이러스 입자 유사체가 관찰되었는데, 이것은 virus-specific vesicle 주위에서 바이러스 조립이 일어나는 것을 추정된다. 한편 원통세포 내에서 봉입체 관찰되고, 변형소구화된 배상세포가 중장강으로 탈락되는 것이 관찰되었다

• 헤리티지:역사와 과학
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• 제33권
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• pp.162-181
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• 2000

This paper investigates sixteen rock-cut arhat images of the Koryo period at Sungbul-sa (成佛寺) in Chunan (天安), South Chungchung Province. These images, together with a Buddha triad in the center, are carved in thin relief on the large granite wall ($375cm{\times}248cm$), and below them is engraved a huge lotus petal which looks to be supporting all the images above. According to extant textual sources, arhats were popularly worshipped in the Koryo period. The Painting of Five Hundred Arhat Images was brought to Koryo from Later Liang (後梁) of the Five Dynasties (五代) in 923. From that time on, the cult of arhat had become gradually known in Koryo. More than thirty ceremonies worshipping arhats (羅漢齊) were officially held in Koryo court. The Sixteen Arhat images (十六羅漢像) were enshrined in many temples. In Boje-sa (普濟寺), which kings and aristocrats often visited for ritual ceremonies, had its main hall dominated by the Five Hundred Arhats, called Nahan-pocheon (羅漢寶殿). However, a limited number of arhat images of the Koryo period, originally made as sets of sixteen or five hundred arhats, are now extant. The Sixteen Arhat images at Sungbul-sa are unique examples that show all sixteen images in situ. The Sixteen Arhat images, though some of them are abraded, show various postures and gesture. One of them sits with his knee bent, and one arhat is sitting on a chair with his hand held upward. Each image is carved in a niche, just as the arhat images of Northern Song China are normally represented in niches of a cave, and are quite similar in style to the arhat images of the Northern Song period at Qinglindong (靑林洞) cave, Feilaifeng (飛來峰), Zejiang province (浙江省). This similarity between the arhat images of Sungbul-sa and those of Qinglindong certifies the strong impact of Song Buddhist art on Koryo frequently mentioned in texts. The Sixteen Arhat images surround the central Buddha raising his hand up to his chest. This Buddha triad could be ascribed to be either the Maitreya Buddha triad or the Sakyamuni Buddha triad based on the Lotus Sutra (妙法蓮華經). Still, the Sakyamuni Buddha triad was more often represented with sixteen or five hundred arhats in the Koryo period, as was seen in the record of Boje-sa where the Sakyamuni triad was enshrined with five hundred arhat images. The Sixteen Arhat images of Sungbul-sa arc most likely to be a rare example of Koryo Arhat images showing the Sakyamuni Buddha triad and the Sixteen Arhats who were predicted to be Buddhas by Sakyamuni in the Lotus Sutra.