• Journal of Microbiology
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• v.33 no.4
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• pp.334-338
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• 1995

The electrophoretic karyotypes of 6 species in different Fusarium sections were examined by using contour-clamped homogeneous electric field (CHEF) gel electrophoresis. Intact chromosomal DNA was prepared from protoplasts and up to 9 distinct bands were separated on 0.7% or 0.8% agarose gel under several different conditions. Putative chromosome numbers varied from 6 to 9 amd polymorphic karyotypes were observed in different Fusarium sections. Using Schizosaccharomyces pombe and Saccharomyces cerevisiae chromosomes as standards, the sizes of the Fusarium spp. chromosomes were estimated. The electrophoretic karyotypes of F. moniliforme and F. subglutinans (section Liseola) were similar. Unidentified filamentour fungi, F. beomiforme was much closer to F. axysporum (section Elecgans) in karyotype and the karyotypes of F. napiforme were more similar to those of section Liseola than any other sections. F. graminearum (section Discolor) had a distinctive electrophoretic karyotype.

• Parasites, Hosts and Diseases
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• v.60 no.3
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• pp.213-215
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• 2022

Turtle leeches have not been recorded in Korea, although they occur in geographically adjacent countries including China and Japan. This study describes a turtle leech, Ozobranchus jantseanus (Clitellata: Ozobranchidae), found from Reeve's turtle (Mauremys reevesii) in Korea. Of the 143 Reeve's turtles collected from the freshwater reservoir in Jinju City, Gyeongsangnam-do, Korea, 95 unidentified leeches were found in 8 (5.6%) individuals. The leeches had 22 somites with 11 pairs of externally exposed branchiae, body-sized posterior suckers, and spines on the dorsal surface. We identified these leeches as Ozobranchus jantseanus Oka, 1912 (Clitellata: Ozobranchidae). This species of turtle leeches found in Korea may fill the gap in the biodiversity of East Asian annulus.

• Journal of Plant Biotechnology
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• v.43 no.2
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• pp.213-222
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• 2016

This study aims to establish a system for the rapid discrimination of Zoysia species using metabolite fingerprinting of FT-IR spectroscopy combined with multivariate analysis. Whole cell extracts from leaves of 19 identified Zoysia japonica, 6 identified Zoysia sinica, and 38 different unidentified Zoysia species were subjected to Fourier transform infrared spectroscopy (FT-IR). PCA (principle component analysis) and PLS-DA (partial least square discriminant analysis) from FT-IR spectral data successfully divided the 25 identified turf grasses into two groups, representing good agreement with species identification using molecular markers. PC (principal component) loading values show that the $1,100{\sim}950cm^{-1}$ region of the FT-IR spectra are important for the discrimination of Zoysia species. A dendrogram based on hierarchical clustering analysis (HCA) from the PCA and PLS-DA data of turf grasses showed that turf grass samples were divided into Zoysia japonica and Zoysia sinica in a species-dependent manner. PCA and PLS-DA from FT-IR spectral data of Zoysia species identified and unidentified by molecular markers successfully divided the 49 turf grasses into Z. japonica and Z. sinica. In particular, PLS-DA and the HCA dendrogram could mostly discriminate the 47 Z. japonica grasses into two groups depending on their origins (mountainous areas and island area). Considering these results, we suggest that FT-IR fingerprinting combined with multivariate analysis could be applied to discriminate between Zoysia species as well as their geographical origins of various Zoysia species.

• Korean Journal of Environmental Agriculture
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• v.23 no.1
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• pp.59-67
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• 2004

The Shihwa constructed wetland was established for the treatment of severely polluted water from Banwoul, Donghwa and Samhwa streams. This study was focused on investigating dynamics of phytoplankton communities in open waters and periphytic algae on reed (Phragmites communis) planting area at 5 stations from October 2001 to July 2002. The concentration of T-N and T-P of inlet stations from the streams were decreased by flowed through the wetland. However, the TN/TP ratios at all stations were shown as a little over 16 indicating that the T-P will play some role as a limitation factor. Phytoplankton communities were identified as a total 413 taxa which were composed of 375 species, 21 varieties, 2 forma and 15 unidentified species. Standing crops of phytoplankton communities and chlorophyll-a concentrations ranged from $330{\sim}36,420\;cells/mL$ and $2.5{\sim}170.7\;{\mu}g/L$ respectively, and showed the decreasing tendency after flowing through the wetland at almost all stations. Dominant species were 14 taxa at all stations which were Euglena oblonga and Synura spinosa etc. Periphytic algae on the reed were a total 329 taxa which were composed of 295 species, 13 varieties, 3 forma and 17 unidentified species. The species numbers were recorded in order of Chlorophyceae-Bascillariophyceae-Cyanophyceae-Euglenophyceae-Chrysophyceae. The relative abundance (%) was showed a seasonal variation from Cyanophyceae to Bascillariophyceae and to Chlorophyceae. Chlorophyll-a concentrations, ie. the biomass of periphytic algae were ranged from $5.5{\sim}363.8\;mg/m^2$. Dominant species were 16 taxa which were Lyngbya angusta of Cyanophyceae in the early investigation, and were changed to Stigeoclonium lubricum of Chlorophyceae, and Nitzschia plea of Bacillariophyceae etc. in the late. Species number, standing crops and chlorophyll-a concentrations of phytoplankton and perphytic algae were shown higher values at the inlet stations than the stations after flowing through the wetland.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.341-350
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• 2004

We examined estuarine macrobenthos in Namdaecheon estuary, Gangneung, Korea, September 22, 1997. A total of 56 species were found together with an abundance of 378 individuals $m^{-2}$/ and a biomass of 20.79 gWWt $m^{-2}$. The major dominant species were unidentified oligochaete followed by different species of polychaetes Hediste japonica, Rhynchospio glutaea, Poecilochaetus trilobatus, Scoloplos armiger, Spiophanes bombyx and a talitrid amphipod Platorchestia crassicornis. The study area was divided into two different groups of stations and species, based on the q -mode and r-mode clustering analysis. In case of q-mode, there are two groups: one is a marine station group and the other is estuarine group. The r-mode clustering analysis showed the two main communities as follows; 1) Marine species group occurred only at station 7, 8 and 9 and 2) Estuarine species group composed of the species present at station 1 to 6 and 10 to 15. In the number of species, the estuarine station group includes 13 species, whereas 43 species were presented in the marine station group. Total macrofaunal abundance and total biomass were higher in the marine station group than those in the estuarine group. The species diversity index was also high in the marine group (> 2), whereas it was less than ca. 1 in the estuarine group.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.452-468
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• 2012

Marine organisms were collected by the stow nets and the stow net on boat fisheries from April 2010 to November 2011 in the Han River Estuary and categorized as 126 species, 61 families, and 5 taxa. The species were consisted with 34 in Crustacea, 5 in Cephalopoda, 79 in Pisces, unidentified jellyfishes in Cnidaria, and Finless porpoise in Mammals. The major species were composed of fish and crustaceans in the Han River Estuary. The dominant species in Crustacea were Chinese ditch prawn (Palaemon gravieri), blue crab (Portunus trituberculatus), Ridgetail prawn (Exopalaemon carinicauda), and mantis crab (Oratosquilla oratoria), and those in Pisces were Korean anchovy (Coilia nasus), and Japanese grenadier anchovy (Coilia mystus). The length structures of the six dominant species have more than one mode in the Han River Estuary. It reflects that the species inhibit during a part of and/or whole lifetime in the Han River Estuary where they utilize as spawning and/or nursery grounds. Freshwater fishes were collected from station D where is the closest location to the Han River stream, and their appearances were well matched with the large amount of freshwater discharge due to flood periods. Principal components analysis (PCA) was carried out with species compositions and showed temporal and spatial differences by the variations of species.

• The Korean Journal of Mycology
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• v.21 no.4
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• pp.293-300
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• 1993

For the enzymes AAT, GmDH, ME, GPI, LDH and IDH, nine, seven, four, nine, seven, and four different phenotypes, respectively, were observed. All six isolates of an unidentified sterile Pythium sp. isolated from field soil showed the same band positions for all six enzymes compared. These phenotypes were not similar to any of the known Pythium species. Two isolates of unknown Pythium species (145 and 299) showed the same band positions for all six enzymes. The phenotypes for all three unknown Pythium spp. were different from the other species in the experiment. Five isolates of P. heterothallicum showed the same band positions for all enzymes compared except one enzyme, lDH. Two isolates of P. torulosum showed the same band petitions for enzymes AAT, GmDH and ME, and three isolates of P. totulosum showed the same positions for enzymes GPI, LDH, and IDH. Single isolates of P. spinosum and P. irregulare showed the same band positions for enzymes AAT, GmDH and GPI. In conclusion, sterile types of Pythium species showed 100% similarities among themselves but did not show any similarity with all isolates of P. heterothallicum and P. spinosum isolate, and showed very low similarities with other isolates in general except with unknown Pythium isolate 306. Similarity levels between different species were low in general with few exceptions.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.121-128
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• 2003

This study was carried out to identify the phylogenetic relationship of Phellinus species and to know its distribution by comparing the DNA sequences of internal transcribed spacer regions(ITS1 and IST2) and 5.8S ribosomal DNA (rDNA) repeat unit. The Phellinus species had their specific sequences in IST1 and 2 regions depending on suedes. The comparison of the ITS sequences of standard strains indicated that the sequences of ITS1 were more variable than those of ITS2. Nine strains of the commercial products of Phellinus species used in this study were identified as P. lintues, P. baumii, P. igniarius, and P. pini. Most of commercial species were P. pini and P. baumii, and P. gilvus was not found. Also, P. linteus was only found in form of mycelial culture rather than fruiting body. Moreover, the species-specific primers were designed based on ITS sequence data. Each species-specific primers were bound in P. lintues(ITSF-PL2R), P. baumii(PB1F-ITS4R), P. igniarius(IF1-IR3), P. pini(PF1-PR3), and P. gilvus(GF2-GR4), respectively. These primer sets would be useful fer the detection of specific-species among unidentified Phellinus species rapidly.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.19-29
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• 1996

The neurological manifestations of AIDS include dementia, encountered even in the absence of opportunistic superinfection or malignancy. The AIDS Dementia Complex appears to be associated with several neuropathological abnormalities, including astrogliosis and neuronal injury or loss. How can HIV-1 result in neuronal damage if neurons themselves are only rarely, if ever, infected by the vitus\ulcorner In vitro experiments from several different laboratiories have lent support to the existence of HIV- and immune-related toxins. In one recently defined pathway to neuronal injury, HIV-infected macrophages/microglia as well as macrophages activated by HIV-1 envelope protein gp120 appear to secrete excitants/neurotoxins. These substances may include arachidonic acid, platelet-activating factor, free radicals (NO - and O$_2$), glutamate, quinolinate, cysteine, cytokines (TNF-${\alpha}$, IL1-B, IL-6), and as yet unidentified factors emanating from stimulated macrophages and possibly reactive astrocytes. A final common pathway for newonal suscepubility appears to be operative, similar to that observed in stroke, trauma, epilepsy, and several neurodegenerative diseases, including Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis. This mechanism involves excessive activation of N-methyl-D-aspartate (NMDA) receptor-operated channels, with resultant excessive influx of Ca$\^$2+/ leading to neuronal damage, and thus offers hope for future pharmacological intervention. This chapter reviews two clinically-tolerated NMDA antagonists, memantine and nitroglycerin; (ⅰ) Memantine is an open-channel blocker of the NMDA-associated ion channel and a close congener of the anti-viral and anti-parkinsonian drug amantadine. Memantine blocks the effects of escalating levels of excitotoxins to a greater degree than lower (piysiological) levels of these excitatory amino acids, thus sparing to some extent normal neuronal function. (ⅱ) Niuoglycerin acts at a redox modulatory site of the NMDA receptor/complex to downregulate its activity. The neuroprotective action of nitroglycerin at this site is mediated by n chemical species related to nitric oxide, but in a higher oxidation state, resulting in transfer of an NO group to a critical cysteine on the NMDA receptor. Because of the clinical safety of these drugs, they have the potential for trials in humans. As the structural basis for redox modulation is further elucidated, it may become possible to design even better redox reactive reagents of chinical value. To this end, redox modulatory sites of NMDA receptors have begun to be characterized at a molecular level using site-directed mutagenesis of recombinant subunits (NMDAR1, NMDAR2A-D). Two types of redox modulation can be distinguished. The first type gives rise to a persistent change in the functional activity of the receptor, and we have identified two cysteine residues on the NMDARI subunit (#744 and #798) that are responsible for this action. A second site, presumably also a cysteine(s) because <1 mM N-ethylmaleimide can block its effect in native neurons, underlies the other, more transient redox action. It appears to be at this, as yet unidentified, site on the NMDA receptor that the NO group acts, at least in recombinant receptors.

• Parasites, Hosts and Diseases
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• v.42 no.1
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• pp.41-44
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• 2004

The pond smelt Hypomesus olidus and minnow Zacco platypus were collected from the Soyang and Daechung Lakes in January 2003, and their metacercarial infections was examined by the muscle compression and artificial digestion techniques. In the Soyang Lake, 161 metacercariae of Clonorchis sinensis (0.35 per fish) were harvested from 459 pond smelts examined. Also, 13 metacercariae of C. sinensis (0.43 per fish), 1 of Metagonimus sp., 4 of Echinostoma sp., 148 of Centrocestus armatus and 44 unidentified species were collected from 30 minnows. In the Daechung Lake, 369 metacercariae of C. sinensis (3.69 per fish) and 51 unidentified species were recovered from 100 pond smelts. The metacercariae of C. sinensis were fed to experimental rats, in which the adult flukes were identified. The pond smelts and minnows collected from the Soyang and Daechung Lakes were verified to be the second intermediate hosts and the sources of human C. sinensis infection.