• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.1-5
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• 2006

One coastal village in Haenam-gun and two in Yeongam-gun, Jeollanam-do were surveyed for intestinal parasite infections by fecal examination. The egg positive rates of Gymnophalloides seoi were high, $24.1\%$ (14/58) in Haenam-gun and $9.3\%$ (11/118) in Yeongam-gun. The egg positive rates of heterophyids, including Heterophyes nocens, and of Clonorchis sinensis were $10.3\%\;and\;6.9\%$ in Haenam-gun, and $14.4\%\;and\;8.5\%$ in Yeongam-gun, respectively. After praziquantel treatment and purgation, a total of 37,761 fluke specimens were recovered from 17 patients; 11 in Haenam-gun and 6 in Yeongam-gun. Gymnophalloides seoi was the most commonly recovered species, with 37,489 specimens in total (2,205 per person). Other recovered flukes included Heterophyes nocens, Stictodora fuscata, Heterophyopsis continua, Pygidiopsis sUmma, and undetermined species. These results indicate that the areas surveyed are new endemic foci of G. seoi.

• Parasites, Hosts and Diseases
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• v.42 no.1
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• pp.19-26
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• 2004

We investigated the induction of resistance to Clonorchis sinensis infection by prior infection in rat and hamster models. Animals were challenged with C. sinensis metacercariae, then treated with praziquantel and reinfected. Worm recovery rate in reinfected animals was used to estimate resistance to reinfection. The determined resistance rates to reinfection in rats and hamsters were 97.7% and 10.3%, respectively. In rats, cure from the primary infection of C. sinensis increased resistant to reinfection, and the greatert the worm burden and the longer the duration of primary infection, the higher was the resistance rate. For primary infection doses of 10, 40 and 100 metacercariae per rat, the resistance rates were 87.4%, 93.8% and 98.4%, respectively. The resistance rates in rats after 2 or 8-week primary infection were 78.7% and 95.3%, respectively. All worms recovered from reinfected rats were immature. When cured rats were administered with methylprednisolone, resistance to reinfection became impaired. These findings indicate that rats develop a high degree of resistance to reinfection by C. sinensis after cure. The growths and maturations of reinfected worms were also impaired.

• The Journal of the Korean Society for Microbiology
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• v.34 no.5
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• pp.491-500
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• 1999

A recent study showed that comparative sequence analysis of rpoB DNAs could reveal natural relationships in genus Mycobacterium [J Clin Microbial. 37 (6). 1999]. rpoB DNAs showed interspecies variation and intraspecies conservation. Based on these data, we developed polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) protocols which enable species differentiation in genus Mycobacterium. When this assay was applied to 24 clinical isolates identified as M. avium complex (MAC) by biochemical test, these were successfully differentiated into M. avium and M. intracellulare. These results were concordant with those obtained by 16s rDNA analysis. It is the first report that PCR-SSCP analysis of rpoB DNA could be used for species differentiation of MAC strains.

• Parasites, Hosts and Diseases
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• v.45 no.1 s.141
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• pp.39-44
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• 2007

A new endemic focus of Gymnophalloides seoi infection has been discovered on Aphae Island(Shinan-gun, Jeollanam-do), Republic of Korea. This area, which is referred to as Bokyong-ri, is a small seashore village located in the northern portion of the island. Fecal samples were collected from a total of 57 residents and examined by the Kato-Katz and formalin-ether sedimentation techniques. Helminth eggs were detected in 37 samples(64.9%); 33 samples were positive for G. seoi eggs(57.9%), 4 for Pygidiopsis summa(7.0%), 13 for other heterophyids(22.8%), 1 for Clonorchis sinensis(1.7%), and 1 for Trichuris trichiura(1.7%). Women(70.4%) revealed higher rates of G. seoi infection than did men(46.7%), and individuals older than 50 years of age also evidenced higher rates of G. seoi infection than in other age groups(P<0.05). In worm collection from 13 G. seoi egg positive cases, G. seoi (total 86,558 specimens), Heterophyes nocens(278), Stictodora sp.(10), Heterophyopsis continua(3), P. summa(3), and unidentified flukes(42) were collected. Oysters, the source of G. seoi infection, were collected from an area proximal to the village and 50 were examined for metacercariae; 47(94%) were found infected and the observed metacercarial density was $9.5{\pm}8.9$ per oyster. The results of this study indicate that Bokyong-ri is a new endemic area of G. seoi infection, with high rates of infection in humans and oysters.

• The Korean Journal of Malacology
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• v.2 no.1
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• pp.13-25
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• 1986

One of the most medically important snail species of Korea is Semisulcospira spp., a member of the freshwater prosobranch family pleuroceridae. The parasites that these snails transmit to humans are mainly Paragonimus westermani and Metagonimus yokogawoi. On the other hand, Semisulcospira snails are edible as a foodstuff in Korea. The present study was first aimed to detect out residual pesticides in the snails collected at the endemic and non-endemic areas of paragonimiasis in Korea and to make relationship to the detectability of larval trematodes shed from the snails. In addition, water specimens from the habitats where the snails were collected were sampled and analysed to elucidate environmental conditions of the habitats. This malaco-ecological survey was done at 7 endemic and 3 non-endemic areas of paragonimiasis for about more than 2 years, May, 1984 through October, 1986. All the water smaples both from the endemic and non-endemic areas of paragonimiasis showed normal ranges of the criteria of upper freshwater streams, with lower B.O.D. (0.4~2.0 ppm) and higher D.O. values (9.5~11.0 ppm) than those in the large river systems Infection rate of digenetic trematodes in total snails collected was 6.7%, but no Paragonimus cercaria was detected out at all even in the endemic areas of paragonimiasis. The ecological factors affecting Paragonimus larvae in the snails were also discussed. A total of 9 chlorinated hydrocarbon pesticieds was targeted to detect out from the tissues of snails. Out of 9 pesticides, aldrin, beta-BHC, p, p-DDT, dieldrin, DDE, lindane, heptachlor and heptachlor epoxide were eluted from the snails. The highest levels of the pesticides were mostly detected out in the snails collected from the Donghae-Chun area of Haman and the Kangwha area of Kyongki-Do, where the lowest infection rates of trematode cercariae (0~0.5%) were revealed. The possibilities that the residual pesticides in the freshwater animals including Semisulcospira snails might be transferable to humans were also discussed.

• Korean Journal of Plant Taxonomy
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• v.47 no.3
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• pp.264-288
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• 2017

In order to organize a new checklist for endemic vascular plants of the Korean Peninsula, 358 taxa of the Korea Forest Service and 375 taxa of the National Institute of Biological Resources were reviewed. In addition, the names of previously published endemic plants above the rank of variety were checked up to 2016. From the two lists, a total of 444 taxa were identified. Among them, 289 taxa were common on the two lists, but 69 and 86 taxa were listed only by the Korea Forest Service and by the National Institute of Biological Resources, respectively. Taxonomic documents including journal papers and dissertations were examined with regard to the 444 taxa. In some cases, opinions of Korean experts in this field were also reflected. From the results, 312 taxa in total were recognized as plants endemic to the Korean Peninsula, while 132 taxa could not be included on the endemic list. On the other hand, 48 taxa, none of which existed on the two lists, were newly listed. In conclusion, the new checklist of vascular plants endemic to Korea was confirmed, with a total of 360 taxa consisting of 64 families, 172 genera, 297 species, 4 subspecies, 51 varieties and 8 hybrids. The new common name Halla-seol-aeng-cho is given to Primula farinosa L. subsp. modesta (Bisset & S. Moore) Pax var. hannasanensis (T. Yamaz.) T. Yamaz. Sillaphyton Pimenov (Deok-u-gi-reum-na-mul-sok) is newly identified as a genus endemic to Korea. However, Pentactina Nakai could not be included on the list of Korean vascular endemic genera.

• Parasites, Hosts and Diseases
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• v.40 no.3
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• pp.157-162
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• 2002

Plasmodium vivax malaria re-emerged in South Korea in 1993, and epidemics continue since then. We examined genetic variation in the region encompassing the apical membrane antigen-1 (PvAMA-1) of the parasites by DNA sequencing of the 22 re-emerging p. vivax isolates. The genotype of the PvAMA-1, which was based on sequence data previously reported for the polymorphic regions, showed that two haplotypes were present at one polymorphic site. Compared with reported data, the two types, SKOR type I and type II, were similar to Chinese CH- l0A and CH-05A isolates, respectively. Thus, the present study showed that two genotypes of AMA-1 genes coexist in the re-emerging Korean P. vivax.

• Parasites, Hosts and Diseases
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• v.38 no.2
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• pp.95-97
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• 2000

A 17 kDa protein from Clonorchis sinensis adults was purified by a procedure including Sephacryl S-200 HR gel filtration and Q-Sepharose anion exchange chromatography. The protein was proved to be a cysteine protease as it showed hydrolytic activity toward Cbz-Phe-Arg-AMC in the presence of dithiothreitol and was inhibited by specific inhibitors such as iodoacetic acid or trans epoxy-succinly-L-leucyl-amido(4 guanidino) butane. The polyclonal antibody raised against the protein reacted to 17 kDa proteins of trematodes such as Paragonimuf westermani, Fasciola hepatica, Opisthorchis viverrini, Gymnophalloides seoi, and Metagonimus yokogawai. The antibody recognized the 17 kDa and 16 kDa cysteine proteases purified from C. sinensis, P. westemani, and G. seoi as well. These results suggest that the 17 kDa protein may be a cysteine protease commonly present in trematodes.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.363-386
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• 2007

Endemic element of the Russian Far East (RFE) flora includes 497 species of 150 genera and 46 families. The level of endemism in structure of regional natural flora reaches 11.1% as a whole, and in structure of its native fraction - 13.1%. As a result of chorologic and ecocenotic analysis of RFE flora endemic element it is revealed that it consists of 8 main geographical groups and 7 main floristic complexes. The largest number of endemic species is concentrated in Arctic - Alpine & Montane (140, 28.2%), Forest (107, 21.5%) and Maritime (88, 17.7%) floristic complexes as well as in Russian Far East - West-Pacific (136, 27.4%), Japan Sea (88, 17.7%) and North-East-Asian - Beringian (69, 13.9%) geographical groups. It's possible to distinguish three main areas with similar eco-geographical differentiation of endemics on RFE as follows: (1) North-East Asia sector of RFE which North-East-Asian - Beringian and Maritime Okhotia - Beringian geographical groups approximately correspond to, (2) Continental part of East Asia sector of RFE (West - Okhotian, Amur - Okhotian, Amur - Ussirian, Okhotsk Sea and Japan Sea groups) and (3) Oceanic part of East Asia sector (Russian Far East - West Pacific group). Taxonomical variety of RFE endemics on these territories makes up accordingly (1) - 99 species (19.9%), (2) - 259 (52.8%) and (3) - 136 (27.4%).

• Korean Journal of Plant Taxonomy
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• v.50 no.3
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• pp.253-261
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• 2020

Carex splendentissima U. Kang & J. M. Chung, endemic to the Korean peninsula, is characterized by staminate terminal spikes and glabrous elliptic perigynia. Based on its broad leaves, androgynous spikes, and tri-stigmatic features, the species has been placed in Carex sect. Siderostictae Franch. ex Ohwi, an East Asian section and a basal group in the genus. To clarify the monophyly and phylogenetic position of the species, a molecular study using the internal transcribed spacer region of nuclear ribosomal DNA and chloroplast DNA (trnL-F) data was conducted. The DNA sequence data of ten taxa in sect. Siderostictae and closely related taxa (two taxa in sect. Surculosae) with outgroups were analyzed based on maximum parsimony and maximum likelihood (ML) criteria. In the analyses, C. splendentissima was monophyletic and placed within the Siderostictae clade (sect. Siderostictae + two species of sect. Surculosae), forming a clade with C. ciliatomarginata and C. pachygyna (endemic to Japan). The clade (C. splendentissima + C. ciliatomarginata + C. pachygyna) shows evidence of diploidy. Furthermore, C. splendentissima is a sister to C. ciliatomarginata in the ML tree, and the two taxa have staminate terminal spikes. This study also updates the distribution of C. splendentissima and provides keys to the four Korean taxa in sect. Siderostictae. To conserve the endemic species C. splendentissima, further research on its genetic and ecological features should be conducted at the population level.