• 제목/요약/키워드: morphogenesis

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L-system 모델을 이용한 대공간 구조물의 형태생성 방안 (Shape Creation of Spatial Structures using L-system Model)

  • 김호수;박영신;이민호;한철희
    • 한국공간구조학회논문집
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    • 제11권3호
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    • pp.125-135
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    • 2011
  • 본 연구에서는 morphogenesis 기법의 L-system 모델을 사용하여 대공간 구조물의 형태 생성 방안을 제공하고자 한다. 이와 같은 L-system 모델은 일반적으로 식물의 성장 과정을 시각화하기 위해 적용되어 왔으나 본 연구는 이를 건축 분야에 적용하기 위한 프로세스가 제안된다. L-system 모텔은 크게 문자열 생성 단계와 문자열 분석 단계로 구성되어 있다. 문자열 생성 단계에서는 초기문자열로부터 최종 문자열을 생생하며, 문자열을 생성하기 위해서는 alphabet, axiom 및 rule에 대한 정의가 필요하다. 또한 문자열 해석 단계에서는 문자열의 의미 부여에 따라 다양하게 해석될 수 있다. 특히 다양한 적용 예제를 통해 대공간 구조물의 형태 생성 모델을 구현한다.

7,12-Dimethylbenz[$\alpha$anthracene 및 N-methyl-N-nitrosourea를 투여한 랫드 유선 조직 배양에 대한 형태학적 변화 (Morphological Changes in the Mammary Organ Culture of the Rat Treated with 7,12-Dimethylbenz[$\alpha$]anthracene and N-methyl-N-nitrosourea)

  • 문지영;정자영;김옥희;이형환
    • Toxicological Research
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    • 제16권4호
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    • pp.275-284
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    • 2000
  • The organ culture model of the whole mammary gland has many advantages for the study of branching morphogenesis and biological characteristics, including tumorigenesis. Prior to whole gland organ culture, rats were treated with 7,12-dimethylbenz[a]anthracene (DMBA) or N-methyl-N-nitrosourea (MNU) for one week. The tramdorming effect and the morphological changes were assessed by the whole mount preparations and histopathological examination in terminal end buds (TEB), terminal ducts (TD), alveolar buds (AB), alveolar lobules (AL) and hyperplastic alveolar nodules (HAN) of the mammary gland. Grossfindings of the mammary glands at dissection were higher branching morphogenesis and larger volume in carcinogen-treated groups than in carcinogen-non-treated groups. Results of the whole mount method were coincided with those of the histopathological observations. Circular TEB, normally maintained AB, AL, and high cellular density were more frequently observed in carcinogen-treated groups than in carcinogen-nan-treated groups. Histopathologically, as a preneoplastic marker, HAN was maintained only in mammary organ culture of the carcinogen-treated groups. These findings suggest that in vivo trans-formation effects by carcinogens persisted during the mammary organ culture. These results were more characteristic in DMBA than in MNU-treated group. Ducts and terminal ducts appeared to have lost morphology during their growths in case of without diethylstilbestrol (DES). The fact that in vitro organ culture without DES was resulted in abnormal ductular morphogenesis confirms that DES is a physiological regulator of ductular epithelial cell growth.

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Effects of Protein Kinase Inhibitors on In Vitro Protein Phosphorylation and on Secondary Metabolism and Morphogenesis in Streptomyces coelicolor A3(2)

  • Hong, Soon-Kwang;Sueharu, Horinouchi
    • Journal of Microbiology and Biotechnology
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    • 제8권4호
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    • pp.325-332
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    • 1998
  • In vitro phosphorylation experiments with a cell extract of Streptomyces coelicolor A3(2) M130 in the presence of ${\gamma}-[^32P]$]ATP revealed the presence of multiple phosphorylated proteins, including the AfsR/AfsK kinases which control the biosynthesis of A-factor, actinorhodin, and undecylprodigiosin. Phosphorylation of AfsR by a cell extract as an AfsK source was significantly inhibited by Ser/Thr protein kinase inhibitors, staurosporine and K-252a, at concentrations giving 50% inhibition ($IC_50$) of $1{\mu}M\;and\;0.1{\mu}M$, respectively. Further in vitro experiments with the cell extracts showed that phosphorylation of multiple proteins was inhibited by various protein kinase inhibitors with different inhibitory profiles. Manganese and calcium ions in the reaction mixture also modulate phosphorylation of multiple proteins. Manganese at 10 mM greatly enhanced the phosphorylation and partially circumvented the inhibition caused by staurosporine and K-252a. A calcium-activated protein kinase(s) was little affected by these inhibitors. Herbimycin and radicicol, which are known as tyrosine kinase inhibitors, did not show any significant inhibition of AfsR phosphorylation. Consistent with the in vitro effect of the kinase inhibitors, they inhibited aerial mycelium formation and pigmented antibiotic production on solid media. On the contrary, when assayed in liquid culture, the amount of actinorhodin produced was increased by staurosporine and K-252a and greatly decreased by manganese. All of these data clearly show that the genus Streptomyces possesses several protein kinases of eukaryotic types which are involved in the regulatory network for morphogenesis and secondary metabolism.

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방사선조사시 태내백서의 지지기형성과정에 관한 실험적 연구 (A STUDY OF MORPHOGENESIS OF DIGITAL MALFORMATION ON RAT EMBRYO BY X-IRRADIATION)

  • 김재덕
    • 치과방사선
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    • 제11권1호
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    • pp.33-40
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    • 1981
  • The author studied on the effects of x-irradiation to the development of digital malformation in gestation rats. The time-matings occured between 6 p.m. and 8 a.m. and females with copulation. plugs at 8 a.m. were isolated and properly marked for evidence of copulation. The lower abdomen of mothers were exposed to x-irradiation on the 11½th day of gestation, the critical period developing digital malformation, respectively 100, 150, 200, 250, 300 and 350 rads. At 18½th day of post-conception total 50 pregnant females were dissected and the incidence of digital malformations were obtained. Rat embryos on the 12, 13, 14, 15, 16th day of gestation irradiated by 250 rads were examined for morphogenesis of digital malformation. Digital radiating lines were examined in water and histologically by H-E stain. Supra vital stain samples by Nile-blue sulfate in 37℃ normal saline were prepared for the observation of cell necrosis regions and morphogenesis of digits. The results obtained were as follows; 1. By x-irradiation on 11th day of gestation, digital malformations of Ectrodactylia, Syndactylia Polydactylia and Hematodactylia were developed. Ectrodactylia showed the effective relationship to the amount of irradiation, however Syndactylia ans Polydactylia did not. 2. By x-irradiation, cell necrosis of digital germ was appeared markedly, but in 48 hours after irradiation was depressed to the periphery of digital germ and in 72hours after irradiation was disappeared. Digital radiating line showed marked stage of malformation in 48hours after irradiation and continued to show the same amount of physiological cell necrosis as the compared control group in 72hours. after irradiaion. But in the Syndactylia, physiological cell necrosis was not able to be recognized. 3. Ectrodactylia induced by x-irradiation was considered as the direct resoult of cell necrosis of digital origin, however, Polydactylia and Syndactylia were considered as the resoult of some effect in repair process of x-irradiation damages.

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Alteration of cellular events in tooth development by chemical chaperon, Tauroursodeoxycholic acid treatment

  • Lee, Eui-Seon;Aryal, Yam Prasad;Kim, Tae-Young;Pokharel, Elina;Kim, Harim;Sung, Shijin;Sohn, Wern-Joo;Lee, Youngkyun;An, Chang-Hyeon;Kim, Jae-Young
    • International Journal of Oral Biology
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    • 제45권4호
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    • pp.190-196
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    • 2020
  • Several factors, including genetic and environmental insults, impede protein folding and secretion in the endoplasmic reticulum (ER). Accumulation of unfolded or mis-folded protein in the ER manifests as ER stress. To cope with this morbid condition of the ER, recent data has suggested that the intracellular event of an unfolded protein response plays a critical role in managing the secretory load and maintaining proteostasis in the ER. Tauroursodeoxycholic acid (TUDCA) is a chemical chaperone and hydrophilic bile acid that is known to inhibit apoptosis by attenuating ER stress. Numerous studies have revealed that TUDCA affects hepatic diseases, obesity, and inflammatory illnesses. Recently, molecular regulation of ER stress in tooth development, especially during the secretory stage, has been studied. Therefore, in this study, we examined the developmental role of ER stress regulation in tooth morphogenesis using in vitro organ cultivation methods with a chemical chaperone treatment, TUDCA. Altered cellular events including proliferation, apoptosis, and dentinogenesis were examined using immunostaining and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. In addition, altered localization patterns of the formation of hard tissue matrices related to molecules, including amelogenin and nestin, were examined to assess their morphological changes. Based on our findings, modulating the role of the chemical chaperone TUDCA in tooth morphogenesis, especially through the modulation of cellular proliferation and apoptosis, could be applied as a supporting data for tooth regeneration for future studies.

인공광원으로 발광다이오우드를 이용한 묘생산 시스템에서 식물생장 및 형태형성 제어 -발광다이오우드의 광강도 및 분광 특성 (Plant Growth and Morphogenesis Control in Transplant Production System using Light-emitting Diodes(LEDs) as Artificial Light Source- Light Intensity and Spectral Characteristics of LEDs-)

  • 김용현
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1999년도 동계 학술대회 논문집
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    • pp.227-233
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    • 1999
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Chloroplast Photoorientation in Adiantum

  • Wada, Masamitsu
    • 한국식물학회:학술대회논문집
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    • 한국식물학회 1996년도 식물학심포지움 식물호르몬과 신호전달
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    • pp.10-17
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    • 1996
  • Fern gametophytes are a good model system to study plant morphogenesis, because of their simple organization and various photocontrolled responses. We studied fern photomorphogenesis including chloroplast photoorientation using Adiantum gametophytes to analyze signal transduction pathways of plant photomorphogenesis. Chloroplast photoorientation will be shown in detail and molecular structure of fern phytochromes and blue light absorbing pigments will also be discussed.

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Somatic Embryogenesis: Morphogenesis, Physiology, Biochemistry and Molecular Biology

  • Thorpe, Trevor A.
    • 식물조직배양학회지
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    • 제27권4호
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    • pp.245-258
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    • 2000
  • Somatic embryogenesis has become a major tool in the study of plant embryology, as it is possible in culture to manipulate cells of many plant species to produce somatic embryos in a process that is remarkably similar to zygotic embryogenesis. Traditionally, the process has been studied by an examination of the ex vitro factors which influence embryo formation. Later structural, physiological and biochemical approaches have been applied. Host recently, molecular tools are being used. Together, these various approaches are giving valuable information on the process. This article gives an overview of somatic embryogenesis by reviewing information on the morphogenesis, physiology, biochemistry and molecular biology of the process. Topics covered include a brief description of the factors involved in the production of embryogenic cells. Carrot cell suspension is most commonly used, and the development of a high frequency and synchronous system is outlined. At the physiological and biochemical lev-els various topics, including the reactivation of the cell cycle, changes in endogenous growth regulators, amino acid, polyamine, DNA, RNA and protein metabolism, and embryogenic factors in conditioned medium are all discussed. Lastly, recent information on genes and molecular markers of the embryogenic process are outlined. Somatic embryogenesis, the best example of totipotency in plant cells, is not only an important tool in studies in basic biology, but is potentially of equal significance in the micropropagation of economically important plants.

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