• Journal of Plant Biology
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• 제33권3호
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• pp.189-196
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• 1990

Suspension cell lines have been newly established from the calli derived from the immuature embryo culture of hexapolid (Triticum aestivum var. sicco), tetrapolid (T. durum) and diploid (T. tauchii or Aegilops squarrosa) wheat species. The chromosomal variation in suspension cultured cell lines was examined and old cell line, C82d, established from T. aestivum var. copain was also used. New method using 1-bromonaphthalene for metaphase rapping of suspension cells was developed. Variation in chromosome number was observed among all the suspension lines. Cells with doubled chromosome number and deleted chromosome were also observed. Extensive structural changes in chromosome were found in C82d line. Chromosome aberrations showed loss of chromosome arms and chromosome segment. The mean chromosome number in suspension cells of T. aestivum var. sicco was 40, in C82d line 33, in T. durum 28 and in T. tauchii 14. The stability of chromosome in suspension cells of diploid and tetrapolid wheats was higher than that of hexaploid wheat.

• 대한임상검사과학회지
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• 제41권1호
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• pp.6-10
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• 2009

Ring chromosome occurs when both telomeres of a chromosome are lost and the remaining portion of the chromosome circularizes to re-establish chromosome stability. This abnormal structure shows mitotic instability unlike the normal chromosomes, causing problems during mitosis. Here, we report one case of "chromosome 4 ring syndrome" on a 6-month-old male patient with growth retardation. Ring chromosome, monosomy, dicentric chromosome were shown by conventional chromosome analysis using peripheral blood. Peripheral blood was used and incubated for 72 hours for chromosome analysis. 3 probes (LSI WHS SpectrumOrange/CEP 4 SpectrumGreen, 4p subtelomere probe, 4q subtelomere probe) were used to detect the origin and breakpoint of ring chromosome 4 by FISH (fluorescense in situ hybridization) technique.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.237.2-237
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• 1995

No Abstract, See Full Text

• 한국발생생물학회지:발생과생식
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• 제18권2호
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• pp.117-125
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• 2014

Vitrification method is widely used in oocyte cryopreservation for IVF but the birth rates are lower than that of the fresh oocyte. One of the known main reasons is structural instability of meiotic spindle and chromosome systems of mature oocyte. To get the best way for keeping competence of matured oocytes, we studied the best conditions for vitrification focused on equilibration times. The mature oocytes were underwent vitrification with current popular method and analyzed the survival rates, microtubule stability and DNA integrity. The survival rates of recovered oocyte are almost same between groups and are more than 93%. The structural configuration of meiotic spindle was well kept in 10 min equilibration group and the stability rate was almost same with that of control. The chromosomal breakdown was observed in all experimental groups, but the chromosomal stability was higher in 10 min equilibration group than the other groups. The 10 min equilibration group showed best condition compared with the other groups. Based on these results, the equilibration time is one of the key factors in successful keeping for competence of mature oocyte. Although, more fine analysis about the effects of physical stress on oocyte during vitrification is needed to define the optimal condition, it is suggested that the optimal equilibration time to get competent oocyte in mouse is 10 min. Information acquired this study may provide insight into intracellular structural events occurring in human oocytes after vitrification and application for cryopreservation of human oocyte.

• 한국동물학회지
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• 제39권1호
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• pp.75-88
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• 1996

OTF9-63 (OTF9)와 P19S1O1A1 (P19) 배종양 세포들의 체세포에 존재하는 불화성 X 염색체의 재활성과 유발 능력을 조사하였다. 배종야 세포와 체세포들의 융합에 의해 얻어진 HATr 클론들의 형태, 염색체 복제 양상을 비롯하여 X 염색체에 존재하나 그 위치는 상당히 먼 유전자들인 Hprt와 Pgk-1의 발현 양상을 분석한 결과, OTF9 세포는 불활성 X 염색체를 재활성화 시킬 수 있는데 반해 P19 세포는 불가능한 것으로 나타났다. 또한, 모든 유합세포는 장기간 배양되었을 때 성염색체의 수가 감소하였으며, 결국 1:2의 성염색체:상염색체의 비율을 나타내었다. 배종양 세포-체세포 융합세포의 이용은 초기 배발생 과정에서 시작되어 난자형성 과정의 감수분열 전까지의 유지되는 X 념색체의 재활성화 기작을 연구하기 위한 실험 방법을 제공한다.

• 한국가금학회지
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• 제36권4호
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• pp.293-300
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• 2009

모체 출산 연령이 늦어짐에 따라 태아의 염색체 이상 빈도는 증가하는 것으로 알려져 있는데, 이는 난자의 노화에 따른 염색체의 비분리 현상의 증가 등이 주된 원인이다. 염색체 양 말단에 존재하는 텔로미어는 염색체의 안정성에 관여하고 세포분열이 진행됨으로써 이의 길이가 짧아져 노화의 지표로 활용되고 있다. 따라서 본 연구는 모체의 노화가 생산 배아에 미치는 영향을 알아보기 위하여 닭의 산란 연령별 배아의 염색체 이상 빈도와 이들의 텔로미어 함량을 분석하였다. 시험 분석은 20주령에서부터 70주령까지의 화이트 레그혼 종을 공시하고 10주 간격으로 생산된 수정란의 초기 배아에 대한 핵형 분석과 양적형광보인법(Q-FISH)을 이용한 모계 및 생산 배아의 텔로미어 함량을 분석하였다. 분석 결과, 초기 배아의 염색체 이상 빈도는 산란 연령에 따른 유의적인 차이가 있었는데, 산란 초기에 상대적으로 높은 염색체 이상 빈도를 보이다가 산란 중기에서 안정된 빈도를 유지하고, 후기부터 다시 이상 빈도가 증가하는 양상을 보여 모체의 노화가 태아의 염색체 이상 빈도에 영향을 미치는 것으로 나타났다. 개체의 텔로미어 함량은 연령이 증가함에 따라 점진적 감소 양상을 나타내는 반면, 모계 연령에 따른 생산 배아들의 텔로미어 함량은 연령 간에 차이가 없는 것으로 나타나 모체의 노화가 수정 배아의 텔로미어 함량에는 영향을 미치지 않는 것으로 보여진다. 이는 배란 후 수정이 된 배아는 초기 발생 과정 중 세포들의 reprograming이 일어나 텔로미어가 복구됨을 의미한다.

• 동력기계공학회지
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• 제21권3호
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• pp.60-65
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• 2017

A GA is one of the best method to find optimal value in searching area. A GA is driven by probabilistic selection that based on the survival of the fittest. So this algorithm need a huge solving time even if it can be used lots of optimizing problem such as structural design, machine learning, system's identification and so on. This GA's characteristic constrain the program to drive offline. Some studies try to use this algorithm on online or reduce the GA's running time with parallel GA or micro GA. Unfortunately these studies still didn't reduce amount of fitness solving. If the chromosome was imported to the system, it affected system's stability. And when the control system uses online GA, it also doesn't have enough learning time. In this study, try to find stability criterion to reduce the chromosome's affection and find the characteristic of the number of population and generation when GA was driven into the wide searching area.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제2권2호
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• pp.115-121
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• 2002

This paper presents an evolutionary design of digital IIR filters using the genetic algorithm (GA) with modified genetic operators and real-valued encoding. Conventional digital IIR filter design methods involve algebraic transformations of the transfer function of an analog low-pass filter (LPF) that satisfies prescribed filter specifications. Other types of frequency-selective digital fillers as high-pass (HPF), band-pass (BPF), and band-stop (BSF) filters are obtained by appropriate transformations of a prototype low-pass filter. In the GA-based digital IIR filter design scheme, filter coefficients are represented as a set of real-valued genes in a chromosome. Each chromosome represents the structure and weights of an individual filter. GA directly finds the coefficients of the desired filter transfer function through genetic search fur given filter specifications of minimum filter order. Crossover and mutation operators are selected to ensure the stability of resulting IIR filters. Other types of filters can be found independently from the filter specifications, not from algebraic transformations.

• Molecules and Cells
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• 제37권2호
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• pp.95-99
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• 2014

Cancer is unique amongst human diseases in that its cellular manifestations arise and evolve through the acquisition of somatic alterations in the genome. In particular, instability in the number and structure of chromosomes is a near-universal feature of the genomic alterations associated with epithelial cancers, and is triggered by the inactivation of tumour suppressor mechanisms that preserve chromosome integrity in normal cells. The nature of these mechanisms, and how their inactivation promotes carcinogenesis, remains enigmatic. I will review recent work from our laboratory on the tumour suppressor BRCA2 that addresses these issues, focusing on new insights into cancer pathogenesis and therapy that are emerging from improved understanding of the molecular basis of chromosomal instability in BRCA2-deficient cancer cells.

• BMB Reports
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• 제46권10호
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• pp.490-494
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• 2013

The phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a tumor-suppressing lipid phosphatase that is frequently absent in breast tumors. Thus, the stability of PTEN is essential for tumor prevention and therapy. The ubiquitin-proteasome pathway has an important role in regulating the functions of PTEN. Specifically, carboxyl terminus Hsp70-interacting protein (CHIP), the E3 ubiquitin ligase of PTEN, can regulate PTEN levels. In this study, we report that BCL-2-associated athanogene 5 (BAG5), a known inhibitor of CHIP activity, reduces the degradation of PTEN and maintains its levels via an ubiquitylation-dependent pathway. BAG5 is identified as an antagonist of cell tumorigenicity.