• Parasites, Hosts and Diseases
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• 제46권2호
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• pp.87-90
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• 2008

Gynaecotyla squatarolae (Digenea: Microphallidae) adult flukes were recovered from experimental chicks at day 4-6 post-infection and their tegumental ultrastructure was observed with a scanning electron microscopy. They were pyriform in shape, and their anterior halves were concaved ventrally. The whole body surface was covered with tegumental spines, which were wide and 16-17 digitated between oral and ventral suckers. The density of spines and number of digits decreased posteriorly. The oral sucker was subterminal and the excretory pore was at the posterior end of the worm. Two ventral suckers were similar in appearance and protruded near midline of the worm. The genital atrium was dextral to the small ventral sucker. The dorsal surface was covered with tegumental spines, but the spines were sparser than on the ventral surface. On the middle portion of the dorsal surface, a small opening presumed to be the Laurer's canal was seen. From these findings, it has been confirmed that the adult G. squatarolae has unique characteristics in the surface ultrastructure.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.175-180
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• 2007

In order to determine the role of Peyer's patch lymphocytes (PPL) in self-clearing of Cryptosporidium parvum infection in murine models, changes in PPL subsets, their cytokine expression, and in vitro IgG1 and IgA secretions by PPL were observed in primary- and challenge-infected C57BL/6 mice. In primary-infected mice, the percentages of CD4+ T cells, CD8+ T cells, slgA+ B cells, IL-2+ T cells, and $IFN-{\gamma}+$ T cells among the PPL, increased significantly (P < 0.05) on day 10 post-infection (PI). Secretion of IgG1 and IgA in vitro by PPL also increased on day 10 PI. However, all these responses, with the exception of IgG1 and IgA secretions, decreased in challenge-infected mice on day 7 post-challenge (= day 13 PI); their IgG1 and IgA levels were higher (P > 0.05) than those in primary-infected mice. The results suggest that murine PPL play an important role in self-clearing of primary C. parvum infections through proliferation of CD4+, CD8+, IL-2+, and $IFN-{\gamma}+$ T cells, and IgG1 and IgA-secreting 8 cells. In challenge infections, the role of T cells is reduced whereas that of 8 cells secreting IgA appeared to be continuously important.

• Parasites, Hosts and Diseases
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• 제41권1호
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• pp.17-25
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• 2003

The tegumental ultrastructure of juvenile and adult Himasthla alincia (Digenea: Echinostomatidae) was observed by scanning electron microscopy. One-, 5- (juveniles) and 20-day-old worms (adults) were harvested from chicks experimentally fed metacercariae from a bivalve, Mactra veneriformis. The juvenile worms were elongated and cu wed ventrally. The head crown bore 31 collar spines, arranged in a single row. The lip of the oral sucker had 12 paired, and 3 single type 1 sensory papillae, and the ventral sucker had about 25 type II sensory papillae. The anterolateral surface between the two suckers was densely packed with tegumental spines with 4-7 pointed tips. The adult worms were more elongated and filamentous, and had severe transverse folds over the whole body surface. On the head crown and two suckers, type 1 and 11 sensory papillae were more densely distributed than in the juvenile worms. Retractile brush-like spines, with 8-10 digits, were seen on the anterolateral surface, whereas claw-shaped spines, with 2-5 digits, were sparsely distributed posteriorly to the ventral sucker The cirrus characteristically protruded out, and was armed with small spines distally. The surface ultrastructure of H. alincia was shown to be unique among echinostomes, especially in the digitation of its tegumental spines, the distribution of sensory papillae and by severe folds of the tegument.

• Parasites, Hosts and Diseases
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• 제35권4호
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• pp.223-232
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• 1997

Metagonimus miyatai n. sp. (Digenea: Heterophyidae) is described based on adult flukes collected from experimental dogs and hamsters fed with metacercariae encysted in the sweetfish, Plecoglossus altivelis, dace, Tribolodon hakonensis and T. taczanowskii, common fat-minnow. Morocco steindachneri pale chub, Zacco platypus, and dark chub, Zacco temmincki, and on those collected from naturally infected humans. The new species was morphologically compared with M. yokogawai and M. takahashii obtained from experimental animals fed with the sweetflsh and the crucian carp, Cnrossius caressius, respectively. The uterine loops of M. miyatai reached near the posterior end of the body through the space between the two testes, whereas those of M. yokogawai, occupied only the space between the acetabulum and anterior border of two testes. This uterine tubule distribution was similar to that of another closely related species, M. takahashii. However vitellaria of M. miyatai ended in front of the posterior end of the left testis, while those of M. takahcshii reached the posterior end of the left testis and ran it over. By raising M. miyatai as a new species, differentiation of M. yokogawai and M. takahashii became very clear. A key to the species of the genus Metagonimus in the Far East has been proposed.

• Parasites, Hosts and Diseases
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• 제43권1호
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• pp.19-25
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• 2005

Protective efficacy of vaccination with Neospora caninum multiple recombinant antigens against N. caninum infection was evaluated in vitro and in vivo. Two major immunodominant surface antigens (NcSAG1 and NcSRS2) and two dense granule proteins (NcDG1 and NcDG2) of N. caninum tachyzoites were expressed in E. coli, respectively. An in vitro neutralization assay using polyclonal antisera raised against each recombinant antigen showed inhibitory effects on the invasion of N. caninum tachyzoites into host cells. Separate groups of gerbils were immunized with the purified recombinant proteins singly or in combinations and animals were then challenged with N. caninum. Following these experimental challenges, the protective efficacy of each vaccination was determined by assessing animal survival rate. All experimental groups showed protective effects of different degrees against experimental infection. The highest protection efficacy was observed for combined vaccination with NcSRS2 and NcDG1. Our results indicate that combined vaccination with the N. caninum recombinant antigens, NcSRS2 and NcDG1, induces the highest protective effect against N. caninum infection in vitro and in vivo.

• Parasites, Hosts and Diseases
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• 제31권1호
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• pp.7-12
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• 1993

반지락(Tapes philippinarurm)에서의 수집한 피낭유충을 동정하기 위하여 ICR계 마우스에 피낭유충을 경구감염시킨 다음 제 7일, 제 10일, 제 14일에 희생시키고 소장을 적출하여 충체를 회수하였다. 그 결과는 다음과 같다. 1.피낭유충은 작은 충체($312{\;}{\times}{\;}202{;\}{\mu\textrm{m}}$)가 피포하지 않은 상태로 감염되어 있고, 구홉반이 크고 잘 발달되었고 측명돌기가 관찰되었다. 장관은 이분지 되어 끝부분이 매우 부풀어 오른 맹관이었으며 복흡반까지 닿아 있었다. Ventral pit는 관찰되지 않았고 생식공은 원형으로 구홉반과 복합반 사이에 위치하였다. 배설낭은 V자 모양으로 두팔부분은 구홉반까지 닿아 있었다. 2.마우스 소장에서의 회수율 평균 20.1% 이었으며 감염 후 10일 째의 회수율이 가장 높았고 14일에는 현저히 간소하였다. 3.성충은 피낭유충과 크기의 차이가 없었다. 난황선은 한 개가 복합반의 왼쪽 옆에 위치하였다. 저장낭은 한부분으로 이루어져 있었고 복흡반보다 전방에 위치하였다. 고환은 한쌍으로 복흡반 후측장에 위치하였고 난소는 오른쪽 고환이 전방에 위치하였다. 충란은 길이 $28{;\}{\mu\textrm{m}}(27-30{;\}{\mu\textrm{m}})$, 폭 $19{;\}{\mu\textrm{m}}(17-20{;\}{\mu\textrm{m}})$으로 껍질이 매우 얇았으며 날개가 있었다. 이상의 결과로 반지락을 제2중간숙주로 하는 Parvatrema timondavidi(Digenea:Gymnophallidae)가 국내에 분포함을 확인하였다.

• Parasites, Hosts and Diseases
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• 제31권1호
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• pp.21-30
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• 1993

간흡충은 담관암 발생의 원인적 요소로 알려졌다. 그러나 간흡충이 담관암을 일으키는 병리 기전은 자세하게 알려져 있지 않다. 본 연구는 15 ppm의 dimethylnitrosamine(DMN)을 먹는 물로 투여한 햄스터에 간흡충을 감염시켜 담관암의 발생여부를 알아보고 담관암의 병리조직학적 변화를 관찰하고자 하였다. DMN을 투여하고 간흡충을 감염시킨 챔스터에서 11주 후에 8마리 중 6마리가 육안적 혹은 조직학적으로 담관암(cholangiocarcinoma)의 소견을 보였으며 나머지 2마리는 담관종(cholangiofibroma)으로 진단할 수 있었으나 부분적으로 악성적인 모습도 관찰 할 수 있었다. 담관암의 병리조직학적 소견은 담관상피세포가 선종상 혹은 유두상의 증식을 나타내고 높은 이형성을 보였으며 점액세포화생과 괴사소를 보이고 있었다. DMN 만을, 혹은 간흡충만을 투여하거나 감염시킨 햄스터들에서는 담관암이 전혀 발생되지 않았다. 본 .실험은 DMN을 투여한 햄스터에 간흡충감염으로 담관암이 발생하는 과정에서 DMN과 간흡충의 협동작용(synergism)을 보여준 것으로 추정한다.

• Parasites, Hosts and Diseases
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• 제37권2호
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• pp.93-99
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• 1999

Eosinohil and IgE responses of interleukin IL(-5 transgenic and normal C3H/HeN mice were studied after experimental infection with Nippostrongylus brasiliensis 9Nb). Intestinal worms were recovered at day 5 post-infection (PI), and numbers of total white blood cells (WBC) and eosinophils, and total serum IgE and anti-hapten (dinitrophenyl)(DNP) specific IgE titers, were measured at days 0,14 and PI. IL-5 mice appeared resistant to Nb infection showing a significantly ower worm recovery rate than normal mice (P<0.05). Total WBC and eosinophil counts (/mm3) were significantly increased in Nb infected normal mice (p<0.05), but unchanged (total WBC) or decreased (eosinophils) in IL-5 mice at day 21 PI. The total serum IgE level remarkably increased in normal mice, but only a little in IL-5 mice at days 14 and 21 PI. Priming with DNP brought about more remarkable increases of the total and anti-DNP specific IgE in normal mice than in IL-5 mice. The results show that IL-5 mice are resistant to Nb infection, and that eosinophil and IgE responses in these mice are not augmented by N infection.

• Parasites, Hosts and Diseases
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• 제34권1호
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• pp.7-14
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• 1996

한국인에 널리 유행하는 Metagonimus속 흡충류의 분류학적 문제점들을 해결하기 위해 다양한 지역에서 채집한 여러 종의 민물어류로부터 Metugonim속 피낭유충을 검출하여 햄스터에 감염 실험을 하였다. 감염실험 결과 은어는 기존에 알려져 있던 M. yokogawnia 피낭유충 외에 M. tokqhashii의 피낭유충에도 감염되어 있는 것이 밝혀졌으며 붕어에는 M. takohoshii의 피낭유충만 이 감염되어 있었다 피라미, 끄리, 갈겨니등에서 검출된 Metqgonim속 피낭유충의 감염실험 결과, 이들 어종은 모두가 Metosonim Miyata type의 피낭유충에만 감염되어 있는 것으로 나타났다. Metagonimus Miyata type의 성충은 여러 가지 특징 및 숙주특이성 등에 의해서 다른 두 종과 구별되었으며. 그 분류학적 위치에 대해서 몇 가지 가능성을 고찰하였다.

• Tuberculosis and Respiratory Diseases
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• 제58권6호
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• pp.619-623
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• 2005

분아균증은 Blastomyces dermatitidis라는 진균에 의해 유발되며, 발생지역으로는 아프리카와 일부 다른 지역에서 발생 보고가 있으나, 호발지역은 북미의 남동부, 남중부, 중서부 지역이며, 국내에서는 아직 발생 보고가 없는 실정이다. 감염은 주로 오염된 토양으로부터 분생자의 흡인으로 인해 주로 폐 감염으로 시작되며, 폐 이외에 주로 침범되는 장기는 피부, 뼈, 중추신경계 등이 있다. 폐 감염의 경우 방사선학적으로 매우 다양한 형태를 보여 진단이 용이하지 않으며, 세균성 폐렴, 결핵, 히스토플라즈마증, 급성호흡곤란증후군, 폐암 등으로 오인되기도 한다. 치료는 경증의 폐감염만 있는 경우에 자연 치유되는 경우가 있으나, 나머지는 장기간의 항진균제 사용이 권장된다. 저자들은 비 유행지역을 여행 후 발생한 분아균증 1례 경험하였기에 보고하는 바이다.