• Parasites, Hosts and Diseases
• /
• 제27권3호
• /
• pp.197-202
• /
• 1989

이 연구는 흰쥐, 개 및 고양이 숙주에 대한 이락촌폐흡충(Paragonimus iloktsuenensis)의 감염력 및 충체 성장 발육을 비교함으로써 개 및 고양이의 숙주 적합성을 알아보고 나아가 이 흡충 의 인체 감염 가능성을 추정해 보고자 실시하였다. 섬진강 하구산 말똥게(Sesarma dehaani)로부터 분리, 수집한 이락촌폐흡충의 피낭유충을 흰쥐, 개 및 고양이에 경구 감염시킨 후 42일을 기준으로 충체를 회수하였으며, 감염 후 42일에 회수한 충체를 유대로 하여 성장 발육을 비교하였다. 감염 후 42일에 흰쥐, 개 및 고양이에서 충체 회수율은 각각 평균 53.4%, 21.9% 및 12.7%이었으나 회수된 충체의 크기가 각각 평균 6.3×3.2mm, 6.3×3.0mm 및 6.2×3.5mm로 차이가 없었고 충체 발육 상에 있어서도 차이가 없었다. 이 연구의 결과는 이탁촌폐흡충의 종숙주로서 개 및 고양이가 충분히 가능함을 나타내었다.

• Parasites, Hosts and Diseases
• /
• 제58권1호
• /
• pp.57-60
• /
• 2020

During the mobile clinic activities in Tak Province, Thailand, Paragonimus sp. eggs were found in a fecal sample of a 72-year-old Karen resident. Paragonimus DNA was amplified from the stool sample and identified to P. heterotremus. The patient did not have any symptoms. Apparent pulmonary lesion was not found on the chest X-ray. The patient admitted habitual consumption of semi-cooked or roasted waterfall crabs for several years. The waterfall crabs collected from stream near the village were found negative for Paragonimus metacercariae. In northern Thailand, paragonimiasis remains as one of the public health concerns and should be ruled out for asymptomatic pulmonary patients.

• Parasites, Hosts and Diseases
• /
• 제38권1호
• /
• pp.17-23
• /
• 2000

Eosinophils are important effector cells in host defense against parasites. Excretory-secretory product (ESP) produced by helminthic worms plays important roles in the uptake of nutrients, migration in the host tissue, and in immune modulation. However little is known about the ability of the ESP to directly trigger eosinophil apoptosis. This study investigated whether the ESP of newly excysted metacercariae of Paragonimus westermani could induce apoptosis in human eosinophils. Apoptosis was assayed by staining the cells with FITC-annexin V, and the cells were analyzed by flow cytometry. It was found that the ESP of newly excysted metacercariae of P. westemani induced a direct time- and concentration-dependent increase in the rate of constitutive apoptosis in mature human eosinophils. Eosinophil apoptosis was first apparent 3 hr after treatment with the ESP and continued to increase after 6 hr of incubation with respect to the cells cultured in the absence of the ESP. While only 2.8% of the eosinophils incubated in the medium for 3 hr were apoptotic, 7.6%, 10.9% and 22.6% of the eosinophils treated with 10. 30 and $100{\;}\mu\textrm{g}/ml$ ESP were apoptotic, respectively. This result suggests that the ESP of newly excysted metacercariae of P. westermani directly induce eosinophil apoptosis, which may be important for the survival of the parasites and the reduction of eosinophilic inflammation in vivo.

• Parasites, Hosts and Diseases
• /
• 제30권4호
• /
• pp.355-358
• /
• 1992

Oxygen radical은 생물체의 산소대사 과정의 부산물로 생성되어 세포내 여러 성분을 불환성화시키거나 미생물에 대한 방어기전으로 작용한다. 기생충에 존재하는 antioxidant enzyme은 숙주의 방어기전에서 유리하는 oxygen radical의 독성을 제거하므로 이 효소의 활성도는 기생충의 생존에 영향을 미친다고 생각하고 있다. 폐흡충은 피낭유충이 종숙주에 침입한 다음 숙주내 조직이행 시기를 거쳐서 폐에 도달하여 성충이 되므로 이 과정에서 각 시기별 산소독성과 이에 대항하는 효소의 환성이 다를 것으로 추정하였다. 폐흡충의 피낭유충과 감염후 4주, 8주, 12주에 얻은 충체의 추출물을 조효소(조효소)로 하여 SOD, catalase, peroxidase, glutathione peroxidase의 활성도를 측정하였다. 각 효소의 비환성도(specific activity) 중 catalase는 피낭유충에서 최고치였으며, SOD 와 peroxidase는 4주 충체에서 가장 높았고, glutathione peroxidase는 8주 충체에서 높았다. 이들 4가지 antioxidant효소의 비환성도는 감염 12주인 성충에서 모두 낮게 측정되어 조직 이행시기의 충체에서 더 높은 효 소 활성도를 지니고 있음을 알 수 있었다.

• Parasites, Hosts and Diseases
• /
• 제39권2호
• /
• pp.119-132
• /
• 2001

An immunoelectron microscopy employing immunogold labeling method was performed to detect tissue origin of Dl fraction (DIA) among 5 antigenic protein fractions partially purified by DEAE- anion exchange chromatography from water- soluble crude antigen (PIWA) of adult Paragonimus iloktsuenensis. Immune reactions of adult worm tissues with rabbit serum immunoglobulin immunized with crude antigen (PI-Ig) and D1 antigen (D1-Ig), as well as rat serum immunoglobulin infected with P. iloktsuenensis were observed. DlA showed strong antigenicity in the intestinal epithelium of the worms during the early infection period of 2-4 weeks after infection. The vitellaria also showed stronger antigenicity than the other tissue sites in immune reaction of tissues against all immunoglobulins from 4 to 33 weeks after vitelline development. Therefore, it is suggested that DlA was mainly originated from the intestinal epithelial tissues before the development of vitelline gland of the parasites. Immune-reactivity of two immunoglobulins (PI-Ig, Dl-Ig) was significantly different in intestinal epithelial cytoplasmic protrusions (CP) and intestinal epithelial secretory granules (SG). In the experimental group with Dl-Ig, gold particles were labeled significantly in CP than in SG when compared to the PI-Ig group. Thus, the major antigenic materials in Dl antigen having a strong antigenicity in the early infection period was considered to be originated from the intestinal epithelial tissue .

• Parasites, Hosts and Diseases
• /
• 제38권2호
• /
• pp.103-106
• /
• 2000

It is well known that the cysteine proteases in excretory-secretory product (ESP) of Paragonimus westermani newly excysted metacercariae (PwNEM) are capable of degrading IgG in vitro. Recent evidence suggests that the IgG-coated surface, such as found on parasites, is one of the most effective physiologic stimuli for granulocyte activation. Therefore, this study was designed to investigate the effect of excretory-secretory product (ESP) of PwNEM on superoxide production of granulocytes stimulated with IgG The 96-well plates were coated with human IgG (0, 10, 30, $100{\;}\mu\textrm{g}/ml$) in the absence or presence of ESP. When granulocytes were incubated in the wells coated with human IgG in the presence of ESP, the level of superoxide production of granulocytes was reduced to about 90% when compared to the cells incubated in the wells coated with IgG alone. This inhibitory effect of the ESP on IgG-induced superoxide production of granulocytes was concentration-dependent. These results suggest that ESP secreted by PwNEM may be important in the control of effector functions of granulocytes stimulated with IgG in human paragonimiasis.

• Parasites, Hosts and Diseases
• /
• 제51권6호
• /
• pp.669-676
• /
• 2013

Lung fluke, Paragonimus heterotremus, is a flatworm causing pulmonary paragonimiasis in cats, dogs, and humans in Southeast Asia. We examined the ultrastructure of the testis of adult P. heterotremus with special attention to spermatogenesis and spermiogenesis using scanning and transmission electron microscopy. The full sequence of spermatogenesis and spermiogenesis, from the capsular basal lamina to the luminal surface, was demonstrated. The sequence comprises spermatogonia, spermatocytes with obvious nuclear synaptonemal complexes, spermatids, and eventual spermatozoa. Moreover, full steps of spermatid differentiation were shown which consisted of 1) early stage, 2) differentiation stage representing the flagella, intercentriolar body, basal body, striated rootlets, and electron dense nucleus of thread-like lamellar configuration, and 3) growing spermatid flagella. Detailed ultrastructure of 2 different types of spermatozoa was also shown in this study.

• 미생물학회지
• /
• 제23권1호
• /
• pp.64-68
• /
• 1985

페디스토마 성충의 단백질을 정제하여 이를 항원으로 면역시킨 mouse의 spleen cell과 myeloma cell을 세포융합 시킨 결과 융합율은 56% 이었고. 3차 cloning한 후의 항체생산율은 89% 이였으며, 이들 융합세포로 부터 IgM을 생산하는 hybridoma clone과 IgG을 생산하는 hybridoma clone을 얻었다. IgM을 생산하는 hybridoma clone의 supernate는 antibody titer가 희석농도 1 : 64까지 양성이었고. IgG을 생산하는 hybridoma clone의 supernate는 1 : 256까지 양성이었다.

• Parasites, Hosts and Diseases
• /
• 제37권4호
• /
• pp.285-287
• /
• 1999

Changes in the expression level of splenocyte $IFN-{\gamma}$mRNA of Sprague-Dawley (SD) rats infected with Paragonimus westermani were analyzed by competitive reverse transcription-polymerase chain reaction (RT-PCR) followed by southern blot. The template RNA was extracted from the splenocytes of rats infected with 20 metacercariae of P. westermani. The products of competitive RT-PCR were subjected to southern blot and enhanced chemiluminescence (ECL), and analyzed with a densitometer. In comparison with that of uninfected control rat splenocytes (value of 1), the levels of mRNA expression of $IFN-{\gamma}$had changed to 0.747 at 1 week post infection (PI), 0.00175 at 2 week PI, 0.0217 at 3 week PI, 0.194 at 4 week PI and then to 0.537 at 5 week PI. The level at 7 week PI had returned to 1.25, comparable with that of uninfected rats. These results show that, when infected with p. westermani, the levels of $IFN-{\gamma}$ mRNA of SD rat splenocytes were remarkably reduced by more than 500 times at 2 week PI and restored to normal level at 7 week PI.

• Parasites, Hosts and Diseases
• /
• 제49권1호
• /
• pp.73-77
• /
• 2011

Paragonimiasis is an infectious disease caused by trematodes of the genus Paragonimus. This trematode can be treated successfully with praziquantel in more than 90% of the cases. Although praziquantel is generally well tolerated, anaphylactic reactions to this drug have been reported in a few cases. We report here a 46-year-old Korean female with paragonimiasis, presumed to be due to Paragonimus westermani, who displayed an allergic reaction to praziquantel and resistance to triclabendazole treatment. The patient was successfully treated with praziquantel following a rapid desensitization procedure. Desensitization to praziquantel could be considered when no alternative drugs are available.