• Parasites, Hosts and Diseases
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• 제23권1호
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• pp.102-110
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• 1985

경북 청진군에서의 폐흡충 침윤상을 알아보기 위해 1984년 3월부터 10월까지 폐흡충의 제 1중간숙주, 다슬기와 분포상과 이들 다슬기에서의 폐흡충 유미유충의 기생상, 제2중간숙주, 가재에서의 본충 피낭유충 기생상 및 주민들에서의 폐흡충 감염상을 조사하였다. 청진군에서 7개지역의 다슬기 서식처를 발견하였으며, 이들 서식처에서의 다슬기의 분포밀도는 하서 Im2당 5∼25개, 평균 15개였으며, 이들 다슬기에서의 폐흡충 유미유충의 기생률은 매우 낮아 0.0152%였다. 폐흡충의 제2중간숙주, 가재에서의 본충 피낭유충 검출률은 18.7%(604마리중 113마리)였으며, 이중 두천계곡에서는 39.0%로 가장 높았으며, 그 다음은 소광계곡(21.6%), 구산계곡(5.9%) 순이었다. 청진군 주민 819명에서의 폐흡충 감염률은 25.8%였으며, 성별 감염률에 있어서 남성은 30.8%, 여성은 19.9%로써 남녀간의 유의적 차를 인정할 수 있었다(t>2). 연령군별 감염률에 있어서는 0∼9세 18.9%로 시작하여 연령이 많아질수록 그 율이 점차로 증가하여 30∼39세 군에서 37.5%로 최고치를 나타내었다. 이상의 성적으로 미루어 보아 경북 소진군에서는 폐흡충 유행지역으로 남아있을 뿐만 아니라, 주민들에서의 폐흡충감염률은 아직도 높음을 알았다.

• Parasites, Hosts and Diseases
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• 제43권1호
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• pp.33-37
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• 2005

Eosinophil degranulation is considered to be a key effector function for the killing of helminthic worms and tissue inflammation at worm-infected lesion sites. However, relatively little data are available with regard to eosinophil response after stimulation with worm-secreted products which contain a large quantity of cysteine proteases. In this study, we attempted to determine whether the degranulation of human eosinophils could be induced by the direct stimulation of the excretory-secretory products (ESP) of Paragonimus westermani, which causes pulmonary paragonimiasis in human beings. Incubation of eosinophils for 3 hr with Paragonimus-secreted products resulted in marked degranulation, as evidenced by the release of eosinophil-derived neurotoxin (EON) in the culture supernatants. Moreover, superoxide anion was produced by eosinophils after stimulation of the ESP. The ESP-induced EDN release was found to be significantly inhibited when the ESP was pretreated with protease inhibitor cocktail or the cysteine protease inhibitor, E-64. These findings suggest that human eosinophils become degranulated in response to P. westermani-secreted proteases, which may contribute to in vivo tissue inflammation around the worms.

• Parasites, Hosts and Diseases
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• 제51권6호
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• pp.683-687
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• 2013

Among Paragonimus species, P. paishuihoensis is one of the most mysterious and poorly understood species. Metacercariae are characterized by having a unique dendritically branched excretory bladder. However, the morphology of the adult worm remains unknown. To date, metacercariae of this species have been reported only in China and Thailand. In this study, we first found P. paishuihoensis metacercariae in freshwater crabs, Potamon lipkei, in Hinheub District, Vientiane, Lao PDR, with a prevalence of 77.7% and the average intensity of 10.3 (range 1-28) metacercariae per crab. The molecular data based on ITS2 and CO1 markers indicated that P. paishuihoensis from Laos and Thailand were almost completely identical and were close to members of the Paragonimus bangkokensis/Paragonimus harinasutai complex. Attempts to infect experimental animals (cats, dogs, and rats) with P. paishuihoensis were unsuccessful, suggesting that these animals might be unsuitable definitive hosts for the species. Further studies are necessary to elucidate the taxonomic status and life cycle of P. paishuihoensis.

• Parasites, Hosts and Diseases
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• 제41권1호
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• pp.47-55
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• 2003

We compared patterns of intraspecific polymorphism of two markers with contrasting modes of evolution, nuclear ribosomal DNA (rDNA) and mitochondrial DNA (mtDNA), in the lung fluke, diploid and triploid Paragonimus westermani from three geographical regions of Korea. The genetic distances between three populations of Korean diploid and triploid P. westermani showed no significant difference in the nucleotide sequences of the mitochondrial cytochrome c oxidase subunit 1 (mtCOI) and ribosomaal second internal transcribed spacer (ITS2) genes. A highly resolved strict-consensus tree was obtained that illustrated phylogenetically useful information of the ITS2 and mtCOI sequences from diploid and triploid P. westermani.

• Parasites, Hosts and Diseases
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• 제40권2호
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• pp.89-92
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• 2002

The cysteine proteases of Paragonimus westermani metacercariae are involved in metacercarial excystment, host immune modulation, and possibly in tissue penetration. In order to clarify the origin of the enzymes, 28 and 27 kDa cysteine proteases in metacercarial excretory-secretory products were purified through the FPLC system using Mono Q column chromatography. The polyclonal antibodies to the enzymes were produced in BALB/c mice. Immunolocalization studies revealed that both cysteine proteases were distributed at the linings of excretory bladder and excretory concretions of the metacercariae. It was suggested that the excretory epithelium of P. westermani undertake the secretory function of metacercarial cysteine proteases, in addition to its role as a route for eliminating waste products.

• Parasites, Hosts and Diseases
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• 제41권4호
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• pp.221-231
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• 2003

To gain information on retrotransposons in the genome of Paragonimus westermani, PCR was carried out with degenerate primers, specific to protease and reverse transcriptase (rt) genes of long-terminal-repeat (LTR) retrotransposons. The PCR products were cloned and sequenced, after which 12 different retrotransposon-related sequences were isolated from the trematode genome. These showed various degrees of identity to the polyprotein of divergent retrotransposon families. A phylogenetic analysis demonstrated that these sequences could be classified into three different families of LTR retrotransposons, namely, Xena, Bel, and Gypsy families. Of these, two mRNA transcripts were detected by reverse transcriptase-PCR, showing that these two elements preserved their mobile activities. The genomic distributions of these two sequences were found to be highly repetitive. These results suggest that there are diverse retrotransposons including the ancient Xena family in the genome of P. westermani, which may have been involved in the evolution of the host genome.

• Tuberculosis and Respiratory Diseases
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• 제56권5호
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• pp.550-554
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• 2004

과거에 비해 최근에는 우리나라에서 기생충 감염의 빈도가 낮아지긴 하였지만, 우리나라에서 비교적 흔한 감염원인 민물 게장등을 섭취한 병력이 있고, 호산구성 흉막 삼출과 말초혈액에서 호산구증다증이 있을 경우, 반드시 기생충 감염의 가능성을 생각해 보아야 한다. 피하조직에서의 폐흡충의 이소기생 례가 빈번한 것은 아니지만, 본 증례와 같이 이동성의 복부 종괴가 있을 경우 조직검사와 면역학적 검사를 통해 기생충 감염 여부에 대한 확인 절차는 반드시 필요하다. 그럼으로써, 결핵이나 폐암등 다른 질환으로의 오진에 의해 발생하는 경제사회적 손실을 최소화할 수 있을 것으로 사료된다.

• Parasites, Hosts and Diseases
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• 제51권6호
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• pp.677-681
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• 2013

Paragonimiasis is an important food-borne parasitic zoonosis caused by infection with lung flukes of the genus Paragonimus. Of the 7 members of the genus known in Thailand until recently, only P. heterotremus has been confirmed as causing human disease. An 8th species, P. pseudoheterotremus, has recently been proposed from Thailand, and has been found in humans. Molecular data place this species as a sister species to P. heterotremus, and it is likely that P. pseudoheterotremus is not specifically distinct from P. heterotremus. In this study, we collected metacercariae of both nominal species (identification based on metacercarial morphology) from freshwater crabs from Phetchabun Province in northern Thailand, Saraburi Province in central Thailand, and Surat Thani Province in southern Thailand. In addition, we purchased freshwater crabs imported from Myanmar at Myawaddy Province, western Thailand, close to the Myanmar-Thailand border. The DNAs extracted from excysted metacercariae were PCR-amplified and sequenced for ITS2 and cox1 genes. The ITS2 sequences were nearly identical among all samples (99-100%). Phylogenies inferred from all available partial cox1 sequences contained several clusters. Sequences from Indian P. heterotremus formed a sister group to sequences from P. pseudoheterotremus-type metacercariae. Sequences of P. heterotremus from Thailand, Vietnam, and China formed a separate distinct clade. One metacercaria from Phitsanulok Province was distinct from all others. There is clearly considerable genetic variation in the P. heterotremus complex in Thailand and the form referred to as P. pseudoheterotremus is widely distributed in Thailand and the Thai-Myanmar border region.

• Journal of Chest Surgery
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• 제12권4호
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• pp.312-317
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• 1979

1] During the period of Jan. 1959, to Aug. 1979, 47 patients of paragonimiasis have been treated in the department of Chest Surgery. 2] The total number of patients who has been admitted and treated in the department of Chest Medicine are 262 and annual distribution of number of patients has been decreased. However, since 1964, the number of patients has been stationary. On the other hand, the total number of patients who has been admitted and treated surgically in the department of Chest Surgery are 47 and the annual distribution of number of patients has not been decreased. 3] The peak age incidence lies in fourth decade [34%], and over halves of patients is in third to fifth decade. Male to female is 8.4 to 1. 4] The symptoms, which are mainly cough, chest pain, dyspnea and blood tinged sputum, developed mostly in two to five years after infestation by Paragonmius westermani. 5] Sputum tests for eggs of Paragonimus westermani were positive in 16 out of 43 patients [37%]. The 93% of patients were positive in skin test for Paragonimus westermani. The patients with negative skin test were 7%, but sputum or stool examination for Paragonimus westermani`s eggs were positive in these negative group of skin test. 6] Chest roentgenogram revealed pleural effusion [41 cases], hydropneumothorax [1 case], atelectasis [1 case] and mediastinal mass [1 case]. 7] All patients were preoperatively treated with Bithionol. The mode of surgery were decortication only [31 cases], pleuropneumonectomy [3 cases], decortication & lobectomy [2 cases], decortication & closure of bronchial fistula [1 case], thoracentesis [1 case] and postural drainage [1 case]. 8] Paragonimiasis is primarily medical disease and well treated by the administration of Bithionol. But the delayed diagnosis and missed diagnosis, especially as pulmonary tuberculosis, make the disease aggravated and chronic. Subsequently, surgical treatment is infrequently required. Chronic empyema due to Paragonimus westermani is much benign than tuberculous empyema thoracis.

• Parasites, Hosts and Diseases
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• 제24권2호
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• pp.194-200
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• 1986

1986년 5월부터 동년 10월까지 폐흡충 침윤지로 알려진 경북 울진군을 관류하는 남대천, 광천, 왕피천에서 가재의 분포상을 조사한 다음 가재에서의 폐흡충 피낭유충 기생상을 조사하였다. 가재의 서식밀도는 한사람이 한시간에 잡을수 있는 가재의 평균수로 표시하였으며, 이번 조사에서는 최소 1마리, 최고 13마리, 평균 4마리를 채집 할 수 있었다. 가재에서의 폐흡충 피낭유충 검출률은 총 피검가재 817마리중 127마리 (15.5%)였으며, 지역별로는 두천계곡에서 25.1%로 가장 높았다. 가재 체부위별 검출상은 감염가재 127마리에서 총 219개의 피낭유충을 검출하였으며, 이중 두흉부(60.7%), 아가미(37.4%), 간(1.8%)순으로 검출 할 수 있었으며, 감염가재 1마리당 평균 유출수는 1.7개 이었다. 이상의 성적으로 미루어 보아 경북 울진군 남대천, 광천, 왕피천 유역은 아직도 폐흡충 침윤지로 남아 있음을 알았다.