• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.249-258
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• 2014

To examine the taxonomic status of Acheilognathus sp. specimens from the Geum River, morphological and genetical characteristics of A. sp., A. yamatsutae and A. majusculus were investigated and compared in detail. Specimens of A. sp. could be distinguished from the other two species by the combination of some morphological characters such as nuptial color, vertebrae, gillrakers and etc. Males of A. sp. had red bands on the outer margin of dorsal and anal fins and a white band on the outer margin of ventral fin in breeding season. A. sp. had larger maximum body length and somewhat more vertebrae than A. yamatsutae, and had fewer gillrakers than A. majusculus. A. sp. appeared as a monophyletic group with A. majusculus and A. cyanostigma based on genetic analysis. In addition, it had even more close relationship with other congeners than A. yamatsutae. Therefore it is presumed that A. sp. from the Geum River may be a distinct species in genus Acheilognathus.

• Economic and Environmental Geology
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• v.8 no.4
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• pp.183-201
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• 1975

The south and southwestern parts of Jeonra-namdo has been known as an alunite province in Korea. The alunite deposits investigated for the present study are Okmaisan, Seongsam, Bugog, Gasado south, Gasado north, Jangsando, Dogcheon and Jungyongri deposits. The main purpose of this study is to depict the genetical origin of the alunite deposits. The rocks distributed in the areas mentioned above consist chiefly of rhyolitic tuff, breccia tuff and andesitic tuff of Cretaceous age which represent different episodes of volcanic activities during Cretaceous epoch. The attitude of bedding of the tuffaceous rocks varies from place to place but generally dips very gently. The alunite deposits are embedded mostly in the rhyolitic tuff so that they appear as layered deposits, this occurrence may be the result of stratigraphic and lithologic controls. The result of this study can be summarized as below. The mineral sequence studied by the mineral paragenesis and the result of the spectrograph anlyses is such that (1) alunite was formed at first and pyrophyllite was nearly contemporaneous with alunite but pyrophyllite formation can be recognized as a secondary mineralization products, (2) kaoline was succeeded to form later and hematite finally deposited, and (3) pyrite was deposited from the begining to the end of the above mineralization period. The compositional change of host rocks is such that CaO, $SiO_2$ and $Na_2O$ were largely removed from the parent rocks and some $Al_2O_3$ and $SO_3$ were transported by the solution so as to enrich the rocks. The sequencial process of such mineralization has resulted in forming those distinguish mineral zones; alunite, kaoline, pyrophyllite, silicifide and sulphide zone which manifest irregular shape. These deposits were formed by hydrothermal solution which was possibly low temperature and contained sulphuric acid originated from $H_2S$ and $SO_2$ gases.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.841-848
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• 2004

Rapid detection of viable Salmonella in pasteurized milk is important to protect public health from food poisoning. Reverse transcriptase-polymerase chain reaction(RT-PCR) is recognized as a molecular genetical method to differentiate between live and dead bacteria The RT-PCR in this study was designed to detect specifically viable Salmonella in milk by using the primers whose nucleotide sequences were determined based on fimA gene which encodes the submit of type 1 fimbriae. Treatment of RNA preparation with RNase-free DNase was adequate enough to destroy DNA, which may otherwise be amplified in the RT PCR Seven strains of Salmonella were detected in the RT-PCR but Escherichia coli, Shigella sonnei, Citrobacter freundii, and Klebsiella pneumoniae were not. $10^7/ml$ and $10^6/ml$ of dead Salmonella which were heat-treated in milk were detectable by using the RT-PCR but $10^5{\sim}10/ml$ of the dead bacteria were not. The sensitivity of the RT-PCR in detecting viable Salmonella was 100 cells/ml.

• Korean Journal of Microbiology
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• v.38 no.3
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• pp.173-179
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• 2002

The functions of riboflavin synthesis genes ( ribI,II,III and IV) found immediately downstream of luxG in the lux operon from Photobacterium species were identified using the biochemical and genetical analysis. The ribI-III gene codes for protein corresponding to that coded by the second (riboflavin synthase), third (3,4-dihydroxy 2-butanone 4-phosphate synthase/GTP cyclohydrolase II) and fourth (lumazine synthase) gene, respectively, of Bacillus subtilis rib operon with the respective gene procuct sharing 41-50% amino acid sequence identity. Unexpectedly, the sequence of the ribIV product of Photobacterium phosphoreum does not correspond in sequence to the protein encoded by the fifth rib gene of Bacillus subtilis. Instead the gene (ribIV) codes for a polypeptide similar in sequence to GTP cyclohydrolase II of Escherichia coli and the carboxy terminal domain of the third rib gene from Bacillus subtilis. Complementation of Escherichia coli riboflavin auxotrophs showed that the function of the gene products of ribII and ribIV are DHBP synthase and GTP cyclohydrolase II, respectively. In addition the experiment, showing that increase in thermal stability of riboflavin synthase coded by ribIon coexpression with ribIII, provided indirect evidence that the latter gene codes for lumazine synthase.

• Proceedings of the Turfgrass Society of Korea Conference
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• 2002.02a
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• pp.3-5
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• 2002

This study was carried out to get better understandings about morphological, ecological, and genetical characteristics of annual bluegrass collected from different golf courses in Korea and eventually to establish a successful control strategy. Twenty five local lines of annual bluegrass collected from 20 golf courses in Korea were classified into annual or perennial type on the basis of morphological characteristics. Twelve local lines showing obvious morphological differences were selected and then genetically assessed using RAPD analysis. Classification of the 12 local lines through RAPD analysis were considerably similar to that determined by both of morphological differences and phenotype. Responses of the two types of annual blugrass to herbicides were also examined. Shoot growth of annual bluegrass was significantly suppressed by flazasulfuron and the annual type was more susceptible than perennial type, regardless of flazasulfuron concentrations used. By pendimethalin treatment, there was no clear difference in susceptibility between the two types of annual bluegrass. However, by the treatment of dithiopyr, annual type was more sensitive than perennial type in both shoot and root growth. Nine tree species were screened to detect their allelopathic potential on turfgrasses and annual bluegrass. Acacia (Robinia pseudo-acacia) leaves showed selective inhibition in the shoot and root growth as well as their seed germination when treated with 2% and 10%(v/v) of the extract. However, the other leaf extracts except acacia inhibited non-selectively the growth of three turfgrass species such as bentgrass, perennial ryegrass and zoysiagrass and annual bluegrass. The PAL activities of annual bluegrass increased at 24 h after treatment of acacia leaf extract and peaked at 36 h and then decreased till 60h. The highest PAL activity was observed at 36h after treatment of 10%. The highest activity of CA4H in annual bluegrass was observed at 2h after treatment of acacia extract and the level was 4 times greater than that of the control. The phenolic acids such as p-coumaric acid, salicylic acid and ferulic acid were increased with the treatment of acacia leaf extract. The chloroplast membrane and cell wall of annual bluegrass were destroyed by treatment of acacia leaf extract and its inner materials were released. The membranes in annual bluegrass cells might be destroyed by phytotoxic compounds from acacia leaf extract.

• The Journal of the Petrological Society of Korea
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• v.1 no.1
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• pp.58-70
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• 1992

From the K-Ar age determinations for the clay deposits and their surrounded rocks in southwest Korea, the ages of the ore formation in all clay deposits fall in very narrow range from 78.1 to 81.4 Ma. K-Ar ages of clay deposits are slightly younger than those of the Cretaceous volcanic rocks (Hwangsan Formation, 81.4 to 86.4 Ma) and are slightly older than those of the Cretaceous granitic rocks (77.1 to 81.5 Ma). These results indicate that clay deposits were formed with genetical relation to late Cretaceous felsic magmatism. Weolgagsan granite, which has been previously considered to be Cretaceous, is proved to be formed its age in Jurassic (140.9 and 144.8 Ma). The close relationships of K-Ar ages between the clay deposits and Cretaceous granitic rocks suggest that the clay deposits were formed during the hydrothermal alterations caused by the thermal effects (hydrothermal circulation) of the granitic intrusions rather than by the hydrothermal activities associated with volcanic activities.

• Journal of Korean Society on Water Environment
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• v.34 no.6
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• pp.661-668
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• 2018

Geosmin is volatile metabolites produced by a range of filamentous cyanobacteria which causes taste and odor problems in drinking water. Molecular ecological methods which target biosynthetic genes (geoA) are widely adopted to detect geosmin-producing cyanobacteria. The aim of this study was to investigate the potential production capability of 8 strains isolated from the Nakdong River. Ultimately, a suggestion for a genetical monitoring tool for the identification of geosmin producers in domestic waters was to be made. Geosmin was detected using solid phase microextraction gas chromatography mass spectrometry (SPME GC-MS) in two strains of Dolichospermum plactonicum (DGUC006, DGUC012) that were cultured for 28 day. The highest concentrations during the experiment period was $17,535ngL^{-1}$ and $14,311ngL^{-1}$ respectively. Additionally, geoA genes were amplified using two primers (geo78F/971R and geo78F/982R) from strains shown to produce geosmin, while amplification products were not detected in any of non-producing strains. PCR product (766 bp) was slightly shorter than the expected size for geosmin producers. According to the BLAST analysis, amplified genes were at nucleotide level with Anabaena ucrainica (HQ404996, HQ404997), Dolichospermum planctonicum (KM13400) and Dolichospermum ucrainicum (MF996872) between 99 ~ 100 %. Both strains were thus confirmed as potential geosmin-producing species. We concluded that the molecular method of analysis was a useful tool for monitoring potential cyanobacterial producers of geosmin.

• Fisheries and Aquatic Sciences
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• v.21 no.12
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• pp.37.1-37.10
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• 2018

The larvae and juveniles of Porocottus leptosomus belonging to the family Cottidae were collected (n = 95, 3.9-16.5 mm in body length, BL) from Busan, Korea, in March 2015. The larvae and juvenile were identified using DNA barcoding as P. leptosomus, and their morphological description was presented in detail. The yolk-sac larvae (3.9-5.6 mm BL) body was slightly compressed, the head was large, the eye was round and large, and the anus was before the middle of the body. The preflexion larvae (5.2-10.0 mm BL) body length drastically increased; caudal fin rays began to occur. The flexion larvae (9.4-11.8 mm BL) notochord flexion started; dorsal, pectoral, and anal fin rays began to occur; pelvic fin buds are seen; they possessed a pair of parietal spine; and a pair of supraocular cirri was first to develop. At 12 mm BL, the notochord was completely flexed. The larva stage (3.9-12.6 mm SL) had the stellate melanophores in the head, isthmus, gut, and tail (along to the ventral midline). During the juvenile stage (11.4-16.5 mm BL), melanophores covered the head and began to form five black bands on the side of the body. The larvae of P. leptosomus spent pelagic life, but moved to the bottom during the juvenile stage. The larvae and juveniles of P. leptosomus differ from other cottid larval fishes by body shape, melanophore head pattern, and spine development. P. leptosomus can be distinguished from Porocottus allisi by morphological development and the occurrence of larval fish: preopercular spine development, melanophore pattern, and caudal fin development.

• Biomolecules & Therapeutics
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• v.31 no.5
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• pp.484-495
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• 2023

Idiopathic pulmonary fibrosis (IPF) can be defined as a progressive chronic pulmonary disease showing scarring in the lung parenchyma, thereby resulting in increase in mortality and decrease in the quality of life. The pathophysiologic mechanism of fibrosis in IPF is still unclear. Repetitive microinjuries to alveolar epithelium with genetical predisposition and an abnormal restorative reaction accompanied by excessive deposition of collagens are involved in the pathogenesis. Although the two FDA-approved drugs, pirfenidone and nintedanib, are under use for retarding the decline in lung function of patients suffered from IPF, they are not able to improve the survival rate or quality of life. Therefore, a novel therapeutic agent acting on the major steps of the pathogenesis of disease and/or, at least, managing the clinical symptoms of IPF should be developed for the effective regulation of this incurable disease. In the present review, we tried to find a potential of managing the clinical symptoms of IPF by natural products derived from medicinal plants used for controlling the pulmonary inflammatory diseases in traditional Asian medicine. A multitude of natural products have been reported to exert an antifibrotic effect in vitro and in vivo through acting on the epithelial-mesenchymal transition pathway, transforming growth factor (TGF)- β-induced intracellular signaling, and the deposition of extracellular matrix. However, clinical antifibrotic efficacy of these natural products on IPF have not been elucidated yet. Thus, those effects should be proven by further examinations including the randomized clinical trials, in order to develop the ideal and optimal candidate for the therapeutics of IPF.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2001.10a
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• pp.37-43
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• 2001

1. About fifty thousand of cattle embryos were transferred and 16000 ET-calves were born in 1999. Eighty percents of embryos were collected from Japanese Black beef donors and transferred to dairy Holstein heifers and cows. Since 1985, we have achieved in bovine in vitro fertilization using immature oocytes collected from ovaries of slaughterhouse. Now over 8000 embryos fertilized by Japanese Black bull, as Kitaguni 7~8 or Mitsufuku, famousbulls as high marbling score of progeny tests were sold to dairy farmers and transferred to their dairy cattle every year. 2. Embryo splitting for identical twins is demonstrated an useful tool to supply a bull for semen collection and a steer for beef performance test. According to the data of Dr. Hashiyada(2001), 296 pairs of split-half embryos were transferred to recipients and 98 gave births of 112 calves (23 pairs of identical twins and 66 singletons). 3. A blastomere-nuclear-transferred cloned calf was born in 1990 by a joint research with Drs. Tsunoda, National Institute of Animal Industry (NIAI) and Ushijima, Chiba Prefectural Farm Animal Center. The fruits of this technology were applied to the production of a calf from a cell of long-term-cultured inner cell mass (1988, Itoh et al, ZEN-NOH Central Research Institute for Feed and Livestock) and a cloned calf from three-successive-cloning (1997, Tsunoda et al.). According to the survey of MAFF of Japan, over 500 calves were born until this year and a glaf of them were already brought to the market for beef. 4. After the report of "Dolly", in February 1997, the first somatic cell clone female calves were born in July 1998 as the fruits of the joint research organized by Dr. Tsunoda in Kinki University (Kato et al, 2000). The male calves were born in August and September 1998 by the collaboration with NIAI and Kagoshima Prefecture. Then 244 calves, four pigs and a kid of goat were now born in 36 institutes of Japan. 5. Somatic cell cloning in farm animal production will bring us as effective reproductive method of elite-dairy- cows, super-cows and excellent bulls. The effect of making copy farm animal is also related to the reservation of genetic resources and re-creation of a male bull from a castrated steer of excellent marbling beef. Cloning of genetically modified animals is most promising to making pig organs transplant to people and providing protein drugs in milk of pig, goat and cattle. 6. Farm animal cloning is one of the most dreamful technologies of 21th century. It is necessary to develop this technology more efficient and stable as realistic technology of the farm animal production. We are making researches related to the best condition of donor cells for high productivity of cloning, genetic analysis of cloned animals, growth and performance abilities of clone cattle and pathological and genetical analysis of high rates of abortion and stillbirth of clone calves (about 30% of periparutum mortality). 7. It is requested in the report of Ministry of Health, labor and Welfare to make clear that carbon-copy cattle(somatic cell clone cattle) are safe and heathy for a commercial market since the somatic cell cloning is a completely new technology. Fattened beef steers (well-proved normal growth) and milking cows(shown a good fertility) are now provided for the assessment of food safety.