• Parasites, Hosts and Diseases
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• v.42 no.4
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• pp.159-167
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• 2004

Sequences of the complete protein-coding portions of the mitochondrial (mt) genome were analysed for 6 species of cestodes (including hydatid tapeworms and the pork tapeworm) and 5 species of trematodes (blood flukes and liver- and lung-flukes). A near-complete sequence was also available for an additional trematode (the blood fluke Schistosoma malayensis). All of these parasites belong to a large flatworm taxon named the Neodermata. Considerable variation was found in the base composition of the protein-coding genes among these neodermatans. This variation was reflected in statistically-significant differences in numbers of each inferred amino acid between many pairs of species. Both convergence and divergence in nucleotide, and hence amino acid, composition was noted among groups within the Neodermata. Considerable variation in skew (unequal representation of complementary bases on the same strand) was found among the species studied. A pattern is thus emerging of diversity in the mt genome in neodermatans that may cast light on evolution of mt genomes generally.

• Parasites, Hosts and Diseases
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• v.48 no.1
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• pp.57-59
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• 2010

A 59-year-old Korean man complained of a painless scrotal hard nodule and weak urine stream. The ultrasound scan revealed a 2.2-cm sized round heteroechogenic nodule located in the extratesticular area. Microscopic hematuria was detected in routine laboratory examinations. On scrotal exploration, multiple spargana were incidentally found in the mass and along the left spermatic cord. On cystoscopy, a 10-mm sized mucosal elevation was found in the right side of the bladder dome. After transurethral resection of the covered mucosa, larval tapeworms were removed from inside of the nodule by forceps. Plerocercoids of Spirometra erinacei was confirmed morphologically and also by PCR-sequencing analysis from the extracted tissue of the urinary bladder. So far as the literature is concerned, this is the first worm (PCR)-proven case of sparganosis in the urinary bladder.

• Parasites, Hosts and Diseases
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• v.52 no.6
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• pp.677-680
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• 2014

Infection cases of diphyllobothriid tapeworms are not much in the below teen-age group. We report a case of Diphyllobothrium nihonkaiense infection in a 13-year-old boy. He presented with severe fatigue, occasional abdominal pain at night time. He also had several episodes of tapeworm segment discharge in his stools. By his past history, he had frequently eaten raw fish including salmon and trout with his families. Numerous eggs of diphyllobothriid tapeworm were detected in the fecal examination. We introduced amidotrizoic acid as a cathartic agent through nasogastroduodenal tube and let nearly whole length (4.75 m) of D. nihonkaiense be excreted through his anus. After a single dose of praziquantel, the child's stool showed no further eggs, and his symptoms disappeared. The evacuated worm was identified as D. nihonkaiense by mitochondrial cox1 gene analysis. Here we report a successful extracorporeal worm extraction from an infection case of D. nihonkaiense by the injection of amidotrizoic acid.

• Molecules and Cells
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• v.23 no.3
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• pp.379-390
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• 2007

We sequenced and characterized the complete mitochondrial genome of the Japanese fish tapeworm D. nihonkaiense. The genome is a circular-DNA molecule of 13607 bp (one nucleotide shorter than that of D. latum mtDNA) containing 12 protein-coding genes (lacking atp8), 22 tRNA genes and two rRNA genes. Gene order and genome content are identical to those of the other cestodes reported thus far, including its congener D. latum. The only exception is Hymenolepis diminuta in which the positions of trnS2 and trnL1 are switched. We tested a PCR-based molecular assay designed to rapidly and accurately differentiate between D. nihonkaiense and D. latum using species-specific primers based on a comparison of their mtDNA sequences. We found the PCR-based system to be very reliable and specific, and suggest that PCR-based identification methods using mtDNA sequences could contribute to the study of the epidemiology and larval ecology of Diphyllobothrium species.

• Parasites, Hosts and Diseases
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• v.26 no.2
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• pp.121-126
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• 1988

Efficacy of praBiquantel (CesocideB injection) by intramuscular (1.M.) route against cestode infections was evaluated. Total 93 domestic or laboratory animals such as dogs, cats, rats, mice, goats, deers and chickens were used. Animals were infected with Dipylidium caninum, Spirometra sp. , Taenia pisiformis, Taenia taeniaeformis, Hymenolepis nana, Moniegia expanse, Moniexia sp. or Raillietina sp. A single dose of prasiquantel, 6 mg/kg of body weight, was highly effective (97.9%) against cestodes of various kinds disregarding the host species or their intensity of infection. At higher dose above 6 mg/kg, the cure rate was 100%. All the cestodes treated were expelled from the host within 48 hours. The discharged proglottides were damaged severely except Hymenolepis nana and Moniegia expanse. Intramuscular injection of this drug evoked a brief pain response in a dog, but no other side reactions were observed.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.43-50
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• 1984

Two cases of human infection by Stellantchasmus falcatus (Heterophyidae) were identified by collection of adult worms during the treatment of some tapeworm infections in Korea. The cases were 24 (Case 1) and 55-year old (Case 2) males residing in Seoul. The Case 1 had gastrointestinal troubles such as diarrhea and abdominal pain, and heart problems such as palpitation and arrhythmia, revealing the eggs of Diphyllobothrium latum in the feces. The Case 2 complained indigestion and discharge of tapeworm (Taenia saginata) segments. Praziquantel at the dose of 15-20mg/kg body weight and 30 g magnesium salt were given to them for treatment of the tapeworm infections and the discharged strobilae were identified. However, concommitantly with the tapeworms, 188 and 5 specimens of S. falcatus were collected from Case 1 and Case 2 respectively through stereomicroscopy of the diarrheal stools. The Case 1 was infected also with 3 other kinds of heterophyid flukes. They said to have eaten raw brackish water fish such as mullets which are considered to be the source of heterophyid fluke infections.

• Parasites, Hosts and Diseases
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• v.51 no.5
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• pp.531-536
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• 2013

Morphological characteristics of Mesocestoides lineatus tetrathyridia collected from Chinese snakes and their adults recovered from experimental animals were studied. The tetrathyridia were detected mainly in the mesentery of 2 snake species, Agkistrodon saxatilis (25%) and Elaphe schrenckii (20%). They were 1.73 by 1.02 mm in average size and had an invaginated scolex with 4 suckers. Adult tapeworms were recovered from 2 hamsters and 1 dog, which were orally infected with 5-10 larvae each. Adults from hamsters were about 32 cm long and those from a dog were about 58 cm long. The scolex was 0.56 mm in average width with 4 suckers of 0.17 by 0.15 mm in average size. Mature proglottids measured 0.29 by 0.91 mm (av.). Ovaries and vitellaria bilobed and located in the posterior portion of proglottids. The cirrus sac was oval-shaped and located median. Testes were follicular, distributed in both lateral fields of proglottids, and 41-52 in number per proglottid. Gravid proglottids were 1.84 by 1.39 mm (av.) with a characteristic paruterine organ. Eggs were 35 by $27{\mu}m$ in average size with a hexacanth embryo. These morphological characteristics of adult worms were identical with those of M. lineatus reported previously. Therefore, it has been confirmed that the tetrathyridia detected in 2 species of Chinese snakes are the metacestodes of M. lineatus, and 2 snake species, A. saxatilis and E. schrenckii, play the role of intermediate hosts.

• Parasites, Hosts and Diseases
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• v.47 no.4
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• pp.369-375
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• 2009

Diphyllobothrium nihonkaiense was first described by Yamane in 1986 but the taxonomical features have been obscure due to lack of critical morphologic criteria in its larval and adult stages. In Korea, this tapeworm had long been known as Diphyllobothrium latum. In this study, we observed 62 specimens collected from Korean residents and analyzed them by morphological features and nucleotide sequences of mitochondrial cox1 gene as well as the ITS1 region. Adult tapeworms were examined after carmine or trichrome stain. Longitudinal sections of the gravid proglottids showed an obtuse angle of about 150 degree between the cirrus sac and seminal vesicle. This angle is known as a major differential point compared with that of D. latum. Nucleotide sequence differences between D. latum and the specimens from Koreans represented 17.3% in mitochondrial DNA cox1 gene. Sequence divergence of ITS1 among 4 Korean isolates was 0.3% and similarity was 99.7% with D. nihonkaiense and D. klebanovskii. All of the Korean specimens analyzed in this study were identified as being D. nihonkaiense (n = 62). We propose its Korean name as "Dong-hae-gin-chon-chung" which means 'long tapeworm of the East Sea' for this newly analyzed diphyllobothriid tapeworm in Korea.

• Parasites, Hosts and Diseases
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• v.53 no.4
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• pp.455-463
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• 2015

The present study was performed to compare the mitochondrial genomes between 2 Spirometra tapeworms, Spirometra erinaceieuropaei and Spirometra decipiens (Cestoidea: Diphyllobothriidae), which larval stages are important etiological agents of sparganosis in humans. For each species, the full mitochondrial genome was amplified in 8 overlapping fragments using total genomic DNA purified from a single worm as the template. The mitochondrial genomes were 13,643 bp (S. erinaceieuropaei) and 13,641 bp (S. decipiens) in length and contained 36 genes; 12 protein-coding genes, 2 ribosomal RNA (rRNA, small and large subunits), and 22 transfer RNAs (tRNAs). The 12 protein-coding genes constituted 10,083 bp (S. erinaceieuropaei) and 10,086 bp (S. decipiens) of their respective mitochondrial genomes. The tRNA genes, ranging in length from 56 to 70 bp, were identified based on putative secondary structures such as the typical cloverleaf shape. A total of 23 intergenic sequences, varying from 1 to 204 bp in size, were interspersed in S. erinaceieuropaei (total, 504 bp) and S. decipiens (total, 496 bp) mtDNA. The 12 protein-coding genes of S. erinaceieuropaei and S. decipiens differed by 12.4%, whereas the overall difference in mtDNA sequence between S. erinaceieuropaei and S. decipiens was 12.9%. Thus, from the standpoint of the mitochondrial genome, S. decipiens represents a valid species that can be distinguished from S. erinaceieuropaei.

• Parasites, Hosts and Diseases
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• v.52 no.4
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• pp.419-423
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• 2014

The present study was performed to know the infection status of intestinal helminths in a most common species of field mice, Apodemus agrarius, from 2 southern regions of Korea. Total 133 and 103 mice were collected by the mouse trap in Hapcheon-gun, Gyeongsangnam-do and Gurye-gun, Jeollanam-do, respectively, from July 2005 to June 2006. The small intestine of each mouse was resected and longitudinally opened with a pair of scissors. The intestinal contents were washed with 0.85% saline until the supernatant became clear. Helminths were collected with naked eyes or under a stereomicroscope from the sediment of the intestinal content. More than 11 species of helminths (4 nematode spp., 5 trematode spp., and 2 cestode spp.) were recovered. Among these, heligmosomoid nematodes (97.5%) was the most highly and heavily infected species. As the members of trematodes, Plagiorchis muris, Brachylaima sp., Echinostoma hortense, Echinostoma cinetorchis, and unidentified echinostome larvae were found in the small intestines of 35 (14.8%), 12 (5.1%), 6 (2.5%), 1 (0.4%), and 1 (0.4%) mice respectively. Two species of tapeworms, Hymenolepis nana and Hymenolepis diminuta were also detected in 79 (33.5%) and 21 (8.9%) mice, respectively. Conclusively, heligmosomoid nematodes were the most prevalent (dominant) species among more than 11 helminth species detected, and Brachylaima sp. fluke is newly added in the list of intestinal trematodes in Korea.