• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.199-204
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• 2007

Metacercariae of Gynaecotyla squatarolae (Digenea: Microphallidae) were discovered from the shore crab, Macrophthalmus dilatatus, purchased at a market in a coastal town of Taean-Eup, Chungcheongnam-do, Republic of Korea. Their adult flukes were confirmed by experimental infection of rats. The metacercariae of G. squatarolae were elliptical ($391.1{\times}362.5{\mu}m$), and the excysted metacercariae had progenetic genital organs, including the ovary and testes. To obtain adult flukes, 6 Sprague-Dawley rats were fed 500 metacercariae each, and killed at days 2, 4, and 6 post-infection. The adult flukes were identified as G. squatarolae (Yamaguti, 1934) Yamaguti, 1939, based on morphological characters, including 2 ventral suckers (1 large and 1 small), a large genital atrium equipped with the cirrus and the metraterm, separated male and female genital pores, a transversely long cirrus pouch, and extensive vitelline follicles. In the present study, it has been first proven that the shore crab M. dilatatus is a second intermediate host for G. squatarolae in the Republic of Korea.

• Parasites, Hosts and Diseases
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• v.37 no.1
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• pp.39-46
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• 1999

As a preliminary study for the explanation of pathobiology of Neodiplostomum seoulense infection. a 54 kDa protease was purified from the crude extract of adult worms by sequential chromatographic methods. The crude extract was subjected to DEAE-Sepharose Fast Flow column, and protein was eluted using 25 mM Tris-HC1 (pH 7.4) containing 0.05. 0.1, 0.2 and 0.4 M NaC1 in stepwise elution. The 0.2 M NaCl fraction was further purified by Q-Sepharose chromatography and protein was eluted using 20 mM sodium acetate (pH 6.4) containing 0.05, 0.1. 0.2 and 0.3 M NaCl, respectively. The 0.1M NaCl fraction showed a single protein band on SDS-PAGE carried out on a 7.5-15% gradient gel. The proteolytic activities of the purified enzyme were specifically inhibited by L-trans-epoxy-succinylleucylamide (4-guanidino) butane (E-64) and iodoacetic acid. The enzyme, cysteine protease. showed the maximum proteolytic activity at pH 6.0 in 0.1 M buffer, and degraded extracellular matrix proteins such as collagen and fibronectin with different activities. It is suggested that the cysteine protease may playa role in the nutrient uptake of N. seoulense from the host intestine.

• Parasites, Hosts and Diseases
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• v.37 no.4
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• pp.271-275
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• 1999

Pneumocystis carinii is the most important opportunistic pathogen of humans in the world. Pneumocystis carinii is experimentally detected in the lungs of rats, mice, rabbits, and monkeys, however, the organisms from different mammals are identical in microscopic morphology. The present study tried to find out more mammalian hosts of P. carinii and also to differentiate the organisms from different mammals by karyotyping. Rats, mice, hamsters, rabbits, cats, and dogs were successfully infected by P. carinii, but guinea pigs and pigs were not. Karyotype of P. carinii from rabbits showed similar size range of chromosomes with that of the prototype, but in different pattern. The patterns from cats and dogs were also different from that of rats. The present study confirms that cats and dogs are infected by P. carinii and at least total three karyotype strains of P. carinii are proven in Korea.

• Parasites, Hosts and Diseases
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• v.48 no.3
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• pp.259-261
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• 2010

Human Gnathostoma hispidum infection is extremely rare in the world literature and has never been reported in the Republic of Korea. A 74-year-old Korean man who returned from China complained of an erythematous papule on his back and admitted to our hospital. Surgical extraction of the lesion and histopathological examination revealed sections of a nematode larva in the deep dermis. The sectioned larva had 1 nucleus in each intestinal cell and was identified as G. hispidum. The patient recalled having eaten freshwater fish when he lived in China. We designated our patient as an imported G. hispidum case from China.

• Parasites, Hosts and Diseases
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• v.51 no.3
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• pp.313-317
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• 2013

According to increase of travel, the cases of imported echinococcosis have been increasing in Korea. The present study was undertaken to develop a serodiagnostic system for echinococcosis in Korea. For diagnosis of echinococcosis, the fluid of Echinococcus granulosus hydatid cysts was collected from naturally infected sheep in Uzbekistan. Also serum samples of infected patients who were surgically confirmed were collected in a hospital in Tashkent, Uzbekistan. According to the absorbance of 59 echinococcosis positive and 39 negative control serum samples, the cut-off value was determined as 0.27. The sensitivity and specificity of ELISA with hydatid fluid antigen were 91.5% and 96%, respectively. The antigen cross-reacted with the serum of some cysticercosis or clonorchiasis patients. However, immunoblot analysis on the cystic fluid recognized antigenic proteins of 7-, 16-, and 24-kDa bands in their dominant protein quantity and strong blotting reactivity. In conclusion, the present ELISA system using hydatid cyst fluid antigen from Uzbekistan sheep is sensitive and specific for diagnosis of echinococcosis cases.

• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.87-89
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• 2006

A 55-year old Korean man, living in Mokpo-city, Jeollanam-do, Republic of Korea, visited a local clinic complaining of right upper quadrant pain and indigestion. At colonoscopy, he was diagnosed as having a carcinoma of the ascending colon, and thus, a palliative right hemicolectomy was performed. Subsequently, an adult fluke of Gymnophalloides seoi was incidentally found in a surgical pathology specimen of the lymph node around the colon. The worm was found to have invaded gut lymphoid tissue, with characteristic morphologies of a large oral sucker, a small ventral sucker, and a ventral pit surrounded by strong muscle fibers. This is the first reported case of mucosal tissue invasion by G. seoi in the human intestinal tract.

• Tuberculosis and Respiratory Diseases
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• v.51 no.5
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• pp.448-452
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• 2001

Coccidioidomycosis is a common infectious disease in southwestern North America, which is caused by the soil fungus, Coccidioides immitis. Due to the mobility of the modem population, increasing numbers of cases are being diagnosed outside the endemic areas. Moreover, diagnosis in non-endenmic areas may be delayed or confused due to its rarity. Here we report a case of pulmonary coccidioidomycosis in an immigrant. The patient presented with unexplained pulmonary symptoms. A history of recent travel to or immigration from an endemic area may suggest coccidioidomycosis. In addition an early tissue biopsy is helpful in establishing this diagnosis.

• Parasites, Hosts and Diseases
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• v.45 no.1 s.141
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• pp.69-74
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• 2007

Trichostrongylus eggs observed in cellophane-thick smears are difficult, in practice, to distinguish from hookworm eggs. In order to overcome these limitations, a molecular approach was conducted. A Trichostrongylus colubriformis adult worm was obtained from a human in Laos, which was identified morphologically. ITS-1 sequence of this worm was determined, and found to be most similar with that of T. colubriformis among the Trichostrongylus spp. reported so far. Then, this sequence was compared with those of human hookworm species, Ancylostoma duodenale and Necator americanus, and species-specific oligonucleotide primers were designed. Polymerase chain reaction(PCR) using these primers evidenced specifically amplified PCR products of Trichostrongylus sp., A. duodenale and N. americanus from the eggs of each(520 bp, 690 bp, and 870 bp, respectively). A species-specific PCR technique can be developed in order to study the epidemiology of Trichostrongylus spp. and hookworms in endemic areas.

• Clinical and Experimental Pediatrics
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• v.53 no.6
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• pp.701-704
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• 2010

Purpose: Dengue fever occurs in many popular tourist destinations and is increasingly imported by returning travelers in Korea. Since Korea is not an endemic country for dengue fever, pediatricians do not usually suspect dengue fever in febrile children even with typical presentation and exposure history. This study was performed to describe the international travel experiences and dengue fever in Korean children. Methods: Travel histories were collected based on questionnaires completed by all patients' guardians who visited the pediatric infectious diseases clinic at Samsung Medical Center from January 2008 to December 2008. For patients who were suspected of dengue fever, a serological test was performed. Results: Five hundred and seventeen children visited the pediatric infectious diseases clinic for the first time during this period. About 30% of patients who responded to the questionnaire (101/339) had experienced international travel within the last 2 years. Four patients were diagnosed with dengue fever by serological test. Conclusion: Increasing numbers of Korean children visit dengue endemic areas and they may return home with dengue fever. Dengue fever should be suspected in patients who have a travel history to endemic areas.

• Tuberculosis and Respiratory Diseases
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• v.66 no.3
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• pp.220-224
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• 2009

Coccidioidomycosis is a fungal infection caused by the soil fungus, Coccidioides immitis, which is endemic to the south-western United States. However, the incidence of coccidioidomycosis has recently increased due to the increase in overseas travel to endemic areas. We report a case of pulmonary coccidioidomycosis diagnosed in an immunocompetent person. A 28-year-old female, who had lived in Phoenix, Arizona, USA for 2 years, was admitted for an evaluation of persistent cough with fever lasting for 2 weeks. The chest X-ray and Chest CT revealed multifocal patchy consolidation and ground-glass opacity in both lungs as well as multiple enlarged right hilar and paratracheal lymph nodes. A percutaneous needLe biopsy of the main mass-like consolidation confirmed mature spherules of Coccidioides immitis in lung tissue. Pulmonary coccidioidomycosis should be considered in patients presenting with persistent cough with fever and a history of travel to or immigration from an endemic area.