• Journal of Plant Biology
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• v.33 no.4
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• pp.237-242
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• 1990

Geographical distribution of diploid plant with AA genome (2n=16) and allotetraploid with AABB genome (2n=34) of Scilla scilloides Complex from Korea has been studied. The composition and frequencies of B chromosomes ere also investigated. Plants with AABB genome were predominant over AA genome plants. A mixed population of AA and AABB genome plants was found for the first time. Aneuploid plants have not been found. Chromosomes of AA genome were composed of three pairs of metacentric, two pairs of submetacentric, two pairs of subtlocentric and one pair of telocentric chromosomes, whereas BB genome was four pairs of metacentric and five pairs of subtelocentric chromosomes. B chromosomes were classified into two categories, isochromosome (F) and chromosome fragment (f). The frequencies of B chromosomes were 43% in AA genome plants and 44% in AABB genome plants. The number of B chromosome ranged from 1 to 3 and 1 to 7 in AA and AABB genome plants, respectively. B chromosome combinations were F and F+f in AA genome plants and F, F+f and f in AABB genome plants.

• The Korea Journal of Herbology
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• v.25 no.1
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• pp.1-7
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• 2010

Objectives : We investigated genetic toxicity of HMCO5 in relation to chromosome aberration test on Cultured Chinese Hamster Lung (CHL) in the presence and absence of S-9 mix. Methods : Experimental groups were divided into two groups: with S-9mix (+S) or without S-9 mix (-S). -S group was also divided 2 series by treatment hours (6 hr: 6-S; or 24 hr; 24-S). Each group treated with vehicle only (complete culture medium), HMCO5 (1,250, 2,500, $5,000\;{\mu}g/ml$), and cyclophosphamide monohydrate (CPA) and ethylmethanesulfonate (EMS), respectively. Results : HMC05 did not show any aberrant metaphase. However, there were significant (p < 0.01) aberrant metaphases with CPA in S+ and with EMS in S-. Conclusions : These results indicate that HMC05 formula does not show any toxicity in chromosome aberration test.

• The Korean Journal of Zoology
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• v.15 no.1
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• pp.15-21
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• 1972

The chromosome constitutions in two cases of uterine carcinoma were studied in vitro with particular interest to the non-random distribution. The results obtained are as follows: 1. The chromosome numbers of one case were found within a normal diploid range with mode at 46, while those of the other were whithin hypotriploid range with mode at 60. 2. The data from the latter case indicated possible existence of non-random distribution of chromosome.

• Plant Resources
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• v.4 no.1
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• pp.48-52
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• 2001

Seven genetic lines of Bupleurum falcatum L. from different geographical regions were analysed for saikosaponin contents and chromosomal numbers. The somatic chromosome numbers of B. falcatum originated from Euisong, Iri, Milyang, Sangnam, Taejon, and Youngchon were 2n=20 while Mishimasaiko showed 2n=26. However, chromosome features were different in plants grown in different geographical regions. Generally, Korean lines had higher saikosaponin contents than Mishimasaiko which is Japanese and Sangnam lines had highest saikosaponin contents compared to other tested lines.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.15-21
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• 1999

The aim of the present study was to determine the effect of paternal sex chromosome on early development of buffalo embryos fertilized and cultured in vitro. Embryos were produced in vitro from abattoir derived buffalo oocytes. The cleaved embryos were cocultured with buffalo oviductal epithelial cells and evaluated on day 7 under the phase contrast microscope to classify development. The embryos which reached the morula/blastocyst stage were fast developing, the embryos which were at 16-32 cell stage were medium developing and the embryos below 16 cell stage were slow developing. The embryos which showed some fragmentation in the blastomeres or degenerated blastomeres, were degenerating. Sex of emberyos (n=159) was determined using PCR for amplification of a male specific BRY. 1 (301 bp) and a buffalo specific satellite DNA (216 bp) fragments. The results thus obtained show that 1) X and Y chromosome bearing sperms fertilize oocytes to give almost equal numbers of cleaved XX and XY embryos, 2) male embryos develop faster than female embryos to reach advanced stage and 3) degeneration of buffalo embryos is not linked with the paternal sex chromosome. We suggest that faster development of males is due to differential processing of X and Y chromosome within the zygote for its activation and / or differential expression of genes on paternal sex chromosome sex chromosome during development of buffalo embryos fertilized and cultured in vitro which may be attributed to a combination of genetic and environmental factors.

• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.172-176
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• 1999

Chromosome of cobitid fishes, Iksookimia yongdokensis collected from the 4 streams flowing to the eastsouthern coast of Korea was studied using chromosome of gill and kidney cells prepared by flame drying technique. The results obtained were as follows: the chromosome number was 100 composed of 44 meta-submetacentric and 56 subtelo-telocentric chromosomes, and the fundamental number (FN) was 144. It was remarked that Iksookimia yongdogensis was distinguishable from its congeners in the karyotype. The above evidences may suggest that Iksookimia yongdokensis was one of the tetraploid species of cobitid fishes.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.292-299
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• 1997

The somatic chromosome numbers among the various taxonomic characters about 17 taxa in Korean Aster and its allied taxa were investigated to review accurate scientific name and taxonomic rank. The somatic chromosome numbers of the treated taxa were invariable in same taxa, but variable among different taxa. The treated taxa were divided into two types by basic chromosome numbers, one type was x=9, the other x=8 and x=9 type was subdivided by polyploidy. The somatic chromosome numbers of Aster altaicus var. uchiymae, A. hyatae, Kalimeris chejuensis were reported firstly in this study, and based upon somatic chromosome numbers and leaf morphology, the plants, idenified as Aster pinnatifidus in Korea was considered variant of Kalimeris incisa.

• Molecules and Cells
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• v.26 no.4
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• pp.356-361
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• 2008

In this work, we have studied the structural and functional linkage between lamin A/C, nuclear actin, and organization of chromosome territories (CTs) in mammary carcinoma MCF-7 cells. Selective down-regulation of lamin A/C expression led to disruption of the lamin A/C perinuclear layer and disorganization of lamin-bound emerin complexes at the inner nuclear membrane. The silencing of lamin A/C expression resulted in a decrease in the volume and surface area of chromosome territories, especially in chromosomes with high heterochromatin content. Inhibition of actin polymerization led to relaxation of the structure of chromosome territories, and an increase in the volumes and surface areas of the chromosome territories of human chromosomes 1, 2 and 13. The results show an important role of polymeric actin in the organization of the nuclei and the chromosome territories.

• The Korean Journal of Malacology
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• v.3 no.1
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• pp.24-34
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• 1987

The melaniid snails belonging to genus Semisulcospira were collected in the Kangwha and Yonchon areas of Korea in 1986 through 1987 in order to carry out a cytotaxonomic study, The snails were first narcotized with menthol and fixed with 70% ethyl alcohol for morphological identification. The gonads of adult snails were used for chromosome analyses by the technique of Imai et al. (1977) with minor modification. Slide preparations were observed under high power fields using a Leitz light miscroscope. The results obtained in the present stuedy are summarized as follows: 1)The sanils collected from Kangwha and Yonchon areas were identified as Semisulcospira forticosta(Martens, 1886)and S. gottschei (Martens, 1886) respectively.2)No specific differences were obwerved in details of the chromosome cycle between S. forticosta and S. gottschei.3) Diploid chromosome numbers observed at mitotic metaphase were 36. There was no difference in chromosome numbers between S. forticosta and S. gottschei.4) There were morphological differences in the karyotypes of the two species. The spermatogonial metaphase karyotype of S. forticosta consists of six pairs of metacentric, eleven pairs of submetacentric, and one pair of acrocentric chromosomes. The spermatogonial metaphase karyotype of S. gottschei consists of five pairs of metacentric, tselve pairs of submetacentric, and one pair of acrocentric chromosomes. Summarizing the aboxe results, the two species of Semisulcospira employed in this study have same chromosome numbers(2n=36)with different karyotypes.

• The Korean Journal of Zoology
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• v.15 no.3
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• pp.95-100
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• 1972

Dose response and time dependence of unscheduled DNA synthesis induced by X-rays were measured to determine if any correlation exists between unscheduled DNA synthesis, modal chromosome number, chromosome exchange and mitotic activity in four mammalian cell strains. Unscheduled DNA synthesis occurred in all strains studied. The rate was dose-dependent and strain-specific. Only HeLa $S_3$ showed a staturated dose response after 4, 000 R, other cells were linearly proportional to dose increases. Time dependence of unscheduled DNA synthesis was completed within 2 hours after irradiation regardless of cell strains. Unscheduled DNA synthesis was not directly related to modal chromosome number, total exchange rate and mitotic activity. Mitotic activity and chromosome exchange were both dose-dependent, but the rates of them were inversely related.