• Parasites, Hosts and Diseases
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• 제48권4호
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• pp.335-338
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• 2010

Maritrema spp. (Digenea: Microphallidae) are parasites of birds, but have not been found in the Republic of Korea. In this study, metacercariae of Maritrema sp. were discovered in the Asian shore crab, Hemigrapsus sanguineus, caught in the mud-flats of Jebu-do, Hwasung-gun, Gyeonggi-do, and the adult flukes were confirmed by experimental infection into mice. Based on the symmetric ribbon-like vitellarium, adult flukes of Maritrema sp. were identified, but did not belong to previously described species in terms of the following morphologic characteristics: ceca reaching to the lateral wall at the anterior border of the ovary; ventral sucker larger than oral sucker; a prominent metraterm; and vitellarium forming a complete ring. Hence, we named this microphallid M. jebuensis n. sp. after the island where the second intermediate hosts were collected. From this study, it has been shown that Maritrema sp. is distributed in Korea and transmitted by the Asian shore crab, H. sanguineus.

• Parasites, Hosts and Diseases
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• 제58권2호
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• pp.201-204
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• 2020

Taenia saginata infection has seldom been reported in Cambodia. In this study, we performed a survey of intestinal parasites in 1,156 residents of Preah Vihear and Stung Treng Provinces in 2018. The results revealed that 26 (2.4%) cases were positive for Taenia spp. eggs. In order to obtain the strobilae of the tapeworms, 2 patients in Preah Vihear were treated with praziquantel and purged with magnesium salts. The proglottids expelled after the medication were morphologically and molecularly analyzed to determine the species. The main uterine lateral braches in gravid proglottids were > 15 in number suggesting that they are either T. saginata or Taenia asiatica. The sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene and 2 nuclear loci, elongation factor-1 alpha (ef1) and ezrin-radixin-moesin-like protein (elp), were identical to the sequences of T. saginata available in GenBank but distant from Taenia solium, T. asiatica, and T. saginata-T. asiatica hybrid. This is the first report of the presence of T. saginata in the northern part of Cambodia bordering Lao PDR based on a molecular confirmation.

• Parasites, Hosts and Diseases
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• 제57권4호
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• pp.451-456
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• 2019

Adult specimens of Echinochasmus caninus n. comb. (Verma, 1935) (Trematoda: Echinostomatidae) (syn. Episthmium caninum Yamaguti, 1958) were recovered from 11 riparian people who resided along the Mekong River in Khammouane Province, Lao PDR. In fecal examinations done by the Kato-Katz technique, the cases revealed eggs of Opisthorchis viverrini/minute intestinal flukes, hookworms, and in 2 cases echinostome eggs. To recover the adult helminths, praziquantel 30-40 mg/kg and pyrantel pamoate 10-15 mg/kg in a single dose were given and purged with magnesium salts. Various species of trematodes (including O. viverrini and Haplorchis spp.), cestodes, and nematodes were recovered from their diarrheic stools. Among the trematodes, small echinostome flukes (n=42; av. 3.8 specimens per case) of 0.7-1.2 mm in length are subjected in this study. They are morphologically characterized by having 24 collar spines interrupted dorsally and anterior extension of vitellaria from the cirrus sac or genital pore level to the posterior end of the body. Particularly based on this extensive distribution of vitellaria, the specific diagnosis was made as Echinochasmus caninus. The cases were co-infected with various other helminth parasites; thus, clinical manifestations specific for this echinostome infection were difficult to determine. The present paper describes for the first time human E. caninus infections in Lao PDR. Our cases marked the 4-14th human infections with this echinostome around the world following the 3 previous cases reported from Thailand.

• Parasites, Hosts and Diseases
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• 제57권3호
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• pp.225-232
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• 2019

Innate lymphoid cells (ILCs) are key players during an immune response at the mucosal surfaces, such as lung, skin, and gastrointestinal tract. Giardia lamblia is an extracellular protozoan pathogen that inhabits the human small intestine. In this study, ILCs prepared from the lamina propria of mouse small intestine were incubated with G. lamblia trophozoites. Transcriptional changes in G. lamblia-exposed ILCs resulted in identification of activation of several immune pathways. Secretion of interleukin (IL)-17A, IL-17F, $IL-1{\beta}$, and interferon-${\gamma}$ was increased, whereas levels of IL-13, IL-5, and IL-22, was maintained or reduced upon exposure to G. lamblia. Goup 3 ILC (ILC3) was found to be dominant amongst the ILCs, and increased significantly upon co-cultivation with G. lamblia trophozoites. Oral inoculation of G. lamblia trophozoites into mice resulted in their presence in the small intestine, of which, the highest number of parasites was detected at the 5 days-post infection. Increased ILC3 was observed amongst the ILC population at the 5 days-post infection. These findings indicate that ILC3 from the lamina propria secretes IL-17 in response to G. lamblia, leading to the intestinal pathology observed in giardiasis.

• Parasites, Hosts and Diseases
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• 제61권3호
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• pp.251-262
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• 2023

Schistosomiasis causes significant morbidity and mortality worldwide. This study aimed to assess the effect of schistosomula lung antigen preparation (SLAP) and soluble egg antigen (SEA) on a murine schistosomiasis mansoni model. Ninety laboratory-bred male Swiss albino mice were divided into 6 groups. Two doses of the vaccine were given at 2-week intervals. All mice were subcutaneously infected with 80±10 Schistosoma mansoni cercariae 2 weeks after the last vaccination dose. They were sacrificed 7 weeks post-infection. Parasitological and histopathological studies were conducted to assess the effect of inoculated antigens (single or combined). The results showed that the combination of SLAP and SEA (combination group) led to a significant reduction in worm burden (65.56%), and liver and intestine egg count (59% and 60.59%, respectively). The oogram pattern revealed a reduction in immature and mature eggs (15±0.4 and 10±0.8, respectively) and an increased number of dead eggs in the combination group (P<0.001). In terms of histopathological changes, the combination group showed notably small compact fibrocellular egg granuloma and moderate fibrosis in the liver. A high percentage of destroyed ova was observed in the intestine of the combination group. This study demonstrates for the first time the prophylactic effect of combined SLAP and SEA vaccine. The vaccine induced a significant reduction in the parasitological and pathological impacts of schistosomiasis mansoni in hepatic and intestinal tissues, making it a promising vaccine candidate for controlling schistosomiasis.

• Parasites, Hosts and Diseases
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• 제61권2호
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• pp.103-126
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• 2023

In the l950s, under the legacy of traditional agriculture, Ascaris lumbricoides, spread epidemically in the war-bitten society of Korea. Consensus on the parasite control was drafted in the Parasite Disease Prevention Act, which passed a parliamentary agreement in 1966, and established safe disposal of feces and mass chemotherapy as control strategies. Biannual stool examinations and treating infected schoolchildren were basic scheme of the control activity through which revenue could be secured for organized business. In the 27 years following 1969, a maximum of 16 million stool examinations had been done every year. Cellophane thick smear enabled the task. The infection declined remarkably in the 1970s when industrialization and green revolution proceeded. A population study of A. lumbricoides in the late 1970s helped us better understand its epidemiology. The data also settled down the understandable protest of teachers against the repeated stool examinations. In the 9 years following 1987, the target population was gradually reduced when the egg positive rate was below 0.1%. An article in the Korean Law, stipulating obligatory stool examinations, was made optional. Although the long-term Korean effort of Ascaris control was a success, the effect of mass chemotherapy was not as succinct in terms of lowering reinfection. In the period of control, Korean agricultural technology changed, and the economy grew and supplied sanitary facilities by which the vicious cycle was disconnected. Reduction of morbidity was a benefit of mass chemotherapy, which is the only control method feasible in economically difficult countries. The most important hurdle of parasite control in the 1960s was poverty of general population and limited financial resources in Korea but the society formed a consensus on the priority of intestinal helminthiasis control during the ordeal period. The national consensus in the 1960s was the critical milestone for Ascaris control in Korea. Under the social agreement, application of timely technical and research advancements in parasitology achieved the success of ascariasis elimination. The successful experience of ascariasis elimination in Korea can be a benchmark for countries where neglected tropical diseases are endemically recycled.

• Applied Microscopy
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• 제41권3호
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• pp.205-213
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• 2011

조피볼락, Sebastes schlegeli 소화관 주변에는 다수의 아니사키 스가 기생하고 있었으며, 몇몇 개체들은 간의 표면에 존재하고 있었다. 유전학적 결과 조피볼락에 기생한 아니사키스는 3종으로 분석되었으며, Hysterothylacium sp.가 가장 많이 분포하고 있었다. Hysterothylacium sp.는 Anisakis simplex보다 짧고 가늘었다. 두 종 모두 전방부분에는 lip, 입, 신경환, 분비공, 분비관이 관찰되었다. 두 종 모두 중간부분에는 식도, 위, 장이 존재하고 있었 지만, intestinal ceacum과 ventricular appendage는 Hysterothylacium sp.에서만 관찰되었다. Hysterothylacium sp.의 후방부분 끝에는 conical nodulose apex이 관찰되었지만, A. simplex의 후방부분 끝에는 spine이 관찰되었다. SEM으로 관찰한 결과 Hysterothylacium sp.의 입 주위에는 3개의 lip이 존재하고 있었는데, dorsal lip은 넓이 65 ${\mu}m$ 내외였고, 한쌍의 lateroventral lip은 넓이 60 ${\mu}m$ 내 외였다. Lip의 표면에는 넓이 8 ${\mu}m$ 내외의 유두돌기 한쌍이 존재하고 있었다. Hysterothylacium sp.와 A. simplex의 충체 넓이는 각각 480 ${\mu}m$와 900 ${\mu}m$ 내외로 측정되었다. Hysterothylacium sp. 의 lateral alae는 높이 7 ${\mu}m$ 내외였으며, cornical nodulose apex에 존재하는 돌기는 지름 약 3.3 ${\mu}m$였다. A. simplex의 후방부분 끝 에는 높이 약 20 ${\mu}m$의 spine이 관찰되었다. 조피볼락 장의 내강 에 존재하는 아니사키스들은 대부분 Hysterothylacium sp.였고, 점막주름 근처 혹은 점막하층에 기생하고 있었다. 아니사키스의 기생으로 인하여 숙주의 점막상피에는 다수의 점액세포가 증가하였다.

• 대한수의학회지
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• 제38권1호
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• pp.147-159
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• 1998

A survey of the internal parasites in 115 fishes of Ophicephalus argus was carried out in Kyungpook province during the period from January 1995 to November 1997. A species of trematode from the stomach and a species of nematode from the caeca of the fishes was discovered respectively. The trematode was identified as Azygia hwangtsinyi (Tsin, 1993) and the nematode as Pingus sinensis ($Hs\ddot{u}$, 1993). The fluke was pressed at thick of 0.1mm~0.2mm between slide glasses and fixed in 70% ethyl alcohol solution. The fluke was washed with tap water after fixation and stained with hematoxylin-carmin and mounted in balsam through routine methods. The nematode was fixed in 5% formalin solution and mounted with lactophnol or glycerine jelly. Morphology : Arygia hwantsinyi ; The fluke is elongate body with approximately parallel margins and rounded extremities in pressed preparations(Fig 1). The cuticle is unarmed. The oral sucker is ventro-subterminal in position. The ventral sucker is slightly smaller than oral sucker and positioned at 14.2% of body length from the oral sucker. The cirrus sac and genital pore is in mid-ventral line, slightly anterior to the ventral sucker. The oral sucker is succeeded by a well developed muscular pharynx. It is succeeded by a short inverted Y-shaped oesophagus. The inner wall of oesophagus is consisted of many fine folded membrane. The fine tubes of esophagus pass into the intestinal heads which are distended and presented a marked borderline between the fine tube and intestinal heads. The Intestinal heads start at level of pharynx and pass caudad in a zigzag course to end quite near caudal margin. The uterine coils occupy the intercecal area between the level of the cephalic margin of the ovary and about the level of the ventral sucker. The uterus is filled with many eggs. The testes are round or oval and placed one behind the other generally a little diagonally. The posterior testis is placed at level of 75.1% of body length. The ovary is oval, placed ahead the anterior testis. The shell gland not discernible outline is contacted with ovary ahead it. The vitelline glands are consisted of small oval vesicles. The vesicles occupy extracecal regions and between a little posterior of the ventral sucker and near caudal margin. Pingus sinensis : Female ; The cuticle is smooth and the cervical alae are well developed. The mouth opening is small, triangular, and without lips. The anterior end bears four sub-medial papillae. The oesophagus is divided into a muscular and glandular portion. The nerve ring is situated just at the junction of the muscular and glandular portions of the oesophagus. The vulva which has a prominent flap, is placed behind the middle of the body about one-third of the length of the worm from the posterior extremity. The vagina is strongly muscularised and after running anteriorly about $68{\mu}$, divides itself into two broad uterine tubes with an anterior and a posterior one. There are a few eggs in the uterine tubes. The tail is slender, straight and pointed. The ovary extends almost to the posterior extremity. Male : Male is smaller than female. The tail is pointed, curved and carrying well-developed caudal alae. A prominent muscular precloacal sucker is characteristic. The spicules are equal and short. There are four pairs of pedunculated pre-anal papillae, of which the most anterior pair are situated just at the level anterior to the muscular sucker. Two pairs of pedunculated papillae are present before the anus. There are five pairs of post-anal papillae of which the most anterior pair and the second counted from the posterior end are ventral and more marked than the ones which are situated laterally.

• Parasites, Hosts and Diseases
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• 제22권1호
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• pp.85-95
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• 1984

한국 시장에서 얻은 명태의 장내 기생 조충류 조사의 일환으로 이 연구를 실시하였다. 명태의 장에서 얻은 각종 충체에 대하여 형태학적 계측과 박절표본을 작성한 소견을 가지고 Schmidt와 Yamaguti의 검색표에 의거하여 속과 종을 동정한 바 다음과 같은 결과를 얻었다. 1. 본 실험에서 국내에 미기록된 신종으로 Eucestoda 아강 Caryophyllidae목 Caryophyllaeidae과 Lytocesinae아과 Khawa속과 Eucestoda아강 Trypanorhyncha목 Acystidea아목 Paranybeliniidae과 Pseudonybelinia속과, Eucestoda아강 Trypanorhyncha목 Aeystidea아목 Tentaculariidae과 Nybelinia속과 Tentacularia속 그리고 Eucestoda아강 Trypanorhyncha목 Cystidae아목 Lacistorhynchidae과 Eulacistorhynchus속과 이들의 종을 확정하였다. 2. Khawia sinesis의 특징은 두절에 소포가 없으며 넓고 펑평하나 가장자리가 들쑥날쑥한 점과 목이 짧고 체부와 두부사이가 명화하지 않은 점이었다. 3. Eulncistorhynchus chiloscyllius의 특징은 두절이 꽤 긴 편이며 가장자리가 들쑥날쑥하지 않다. 구문낭도 길다. 수축근은 남의 기저부에 부착되어 있다. 흡구는 둘로 난형 혹은 원형이며 후단에, 절흔이 없다. 촉모는 길 갈고리들이 변형되어 있으며 이중의 chainette가 있다. 체절은 acraspedote하고 성숙체질은 체폭보다 길이가 더 길다. 4. Tentacularia coryphaenea의 특징은 두절이 들쑥 날쑥하지 않고 원주형이다. 흡구는 분리되었고 후단 유리 연에는 작은 가시가 있다. 두절에서 나온 4개의 수축성 촉모에는 갈고리들이 나선형으로 배열되어 있다. 촉모를 둘러싼 초는 꼬여있지 않다. 근낭은 긴 타원형이다. 5. Pseudonybelinia odontacantha의 특징은 두절이 들쑥날쑥하지 않고 촉모는 계구의 전쳔부에 가까이 부착되어 있다. 갈고리는 좌측으로 부터 나선상으로 배열되어 있다. 근낭은 폭보다 길이가 3배정도 긴다. 6. Nykelinia lingu구곤의 특징은 두절이 짧고 들쑥 날쑥하지 않다 흡구는 4개로 분리되어 있으며 각기 자유판을 갖고 있다. 촉모는 원통상으로 단단한 갈고리로 무장되어 있다.

• 대한의생명과학회지
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• 제11권3호
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• pp.259-266
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• 2005

Mast cells and goblet cells have been known to protect the host against parasites. In this study, we examined the response of the mast cells and goblet cells over a period of 6 weeks in the duodenum, jejunum and ileum of C3H/HeN and C57BL/6 mice infected with Echinostoma hortense (E. hortense). In addition, we investigated whether the worm recovery rate of uninfected mice (the control group) or E. hortense-infected mice (the experimental group) was associated with the number of mast cells and goblet cells. The worm recovery rate was higher in the C3H/HeN mice than in the C57BL/6 mice. The number of goblet cells significantly increased in the experimental group of the C3H/HeN and C57BL/6 mice compared with the control group of both strains (P<0.005). Worm recovery peaked 3 weeks after the infection of the C57BL/6 mice and at 2 weeks after the infection of the C3H/HeN mice, and it was higher in the duodenum than in the jejunum and ileum. However, the infected site in the intestine had no relation with worm expulsion. In the C3H/HeN and C57BL/6 mice, the number of goblet cells in the experimental group was significantly higher than that in the control group (P<0.005). The number reached a peak 2 weeks after the infection and it even increased in duodenum, jejunum and ileum. The increased number of goblet cells was retained 6 weeks after infection. The number of goblet cells was higher in the C3H/HeN mice than in the C57BL/6 mice (P<0.01). These results indicate that goblet cells are related with the worm expulsion. Furthermore, immunohistostaining of the antral intestinal walls for lectin showed the significant increase of the number of goblet cells in the experimental group (P<0.001). The high infection rate in the duodenum was found during the early infection. An increased infection rate in the jejunum and ileum was found 3 weeks after infection and the infection rate was higher in the C3H/HeN mice than in the C57BL/6 mice. Taken together, the present study indicates that goblet cells, rather than mast cells, may play critical roles in parasite expulsion.