• 제목/요약/키워드: swelling degree

검색결과 262건 처리시간 0.024초

Release of Cytochrome c from Isolated Mitochondria by Etoposide

  • Park, Jung-Hee;Kim, Tae-Hyoung
    • BMB Reports
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    • 제38권5호
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    • pp.619-623
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    • 2005
  • The efficacy of chemotherapeutic agents on tumor cells has been shown to be modulated by tumor suppressor gene p53 and its target genes such as Bcl-2 family members (Bax, Noxa, and PUMA). However, various chemotherapeutic agents can induce cell death in tumor cells that do not express the functional p53, suggesting that some chemotherapeutic agents may induce cell death in a p53-independent pathway. Here we showed that etoposide can induce the similar degree of cell death in p53-deficient HCT 116 cells, whereas 5'-FU-mediated cell death is strongly dependent on the existence of functional p53 in HCT 116 cells. Further, we provide the evidence that etoposide can induce the cytochrome c release from isolated mitochondria, and etoposide-induced cytochrome c release is not accompanied with the large amplitude swelling of mitochondria. These data suggest that etoposide can directly induce the mitochondrial dysfunction irrespective of p53 status, and it may, at least in part, account for the p53-independent pathway in cell death induced by chemotherapeutic agents.

Titanium Dioxide Nanoparticles filled Sulfonated Poly(ether ether ketone) Proton Conducting Nanocomposites Membranes for Fuel Cell

  • Kalappa, Prashantha;Hong, Chang-Eui;Kim, Sung-Kwan;Lee, Joong-Hee
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2005년도 추계학술발표대회 논문집
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    • pp.87-90
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    • 2005
  • This paper presents an evaluation of the effect of titanium dioxide nanoparticles in sulfonated poly(ether ether ketone) (SPEEK) with sulfonation degree of 57%. A series of inorganic-organic hybrid membranes were prepared with a systematic variation of titanium dioxide nanoparticles content. Their water uptake, methanol permeability and proton conductivity as a function of temperature were investigated. The results obtained show that the inorganic oxide network decreases the proton conductivity and water swelling. It is also found that increase in inorganic oxide content leads to decrease of methanol permeability. In terms of morphology, membranes are homogeneous and exhibit a good adhesion between inorganic domains and the polymer matrix. The properties of the composite membranes are compared with standard nafion membrane.

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찹쌀의 수침중 성질 변화 (Changes in Properties of Waxy Rice During Steeping in Water)

  • 김관;강길진;이용현;김성곤
    • 한국식품과학회지
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    • 제25권1호
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    • pp.86-87
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    • 1993
  • The steeping of waxy rice in water at $20^{\circ}C$ for 12 hr resulted in the decrease of protein, crude fat and ash contents. Water-binding capacity and swelling power (at $80^{\circ}C$) of waxy rice flour increased upon steeping. Maximum viscosity of waxy rice flour in 0.19 N sodium hydroxide solution was increased up to 6 hr steeping and decreased thereafter. The amylograph indices increased as the steeping time increased. The degree of changes in properties during steeping was different between two waxy rice cultivars.

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The Effect of Clay Concentration on Mechanical and Water Barrier Properties of Chitosan-Based Nanocomposite Films

  • Rhim, Jong-Whan
    • Food Science and Biotechnology
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    • 제15권6호
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    • pp.925-930
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    • 2006
  • Chitosan-based nanocomposite films were prepared using a solution intercalation method incorporating varying amounts of organically modified montmorillonite (Cloisite 30B) from 0 to 30 wt%. The nanocomposite films prepared were optically clear despite a slight decrease in the transmittance due to the spatial distribution of nanoclay. X-ray diffraction patterns indicated that a certain degree of intercalation or exfoliation formed when the amount of clay in the film was low and that microscale tactoids formed when the clay content in the sample was high (more than 10 wt%). The tensile strength (TS) of the chitosan film increased when the clay was incorporated up to 10 wt% and then decreased with further increases in the clay content of the film. The elongation at break (E) increased slightly upon the addition of low levels of clay up to 5 wt% and then decreased with further increases in the amount of the clay in the film. The water vapor permeability (WVP) decreased exponentially with increasing clay content. The water solubility (WS) and swelling ratio (SR) of the nanocomposite films decreased slightly, indicating that the water resistance of the chitosan film increased due to the incorporation of the nanoclay.

Poly(hydroxypropyl methacrylate-co-N-vinylpyrrolidone) hydrogel의 합성과 콘텍트렌즈에의 응용 (Synthesis of Poly(hydroxypropyl methacrylate-co-N-vinylpyrrolidone) hydrogel and its Application to the Contact Lens)

  • 조종수
    • 대한의용생체공학회:의공학회지
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    • 제9권1호
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    • pp.67-72
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    • 1988
  • Poly (HPMA/NVP) hydrogel was synthesized according to the composition and the con- centration of the crosslinking agent. The swelling degree of the P(HPMA/NVP) hydrogel decreased with increasing of P(HPMA) composition and crosslinking agent. The glass transi- tion and softening temperatures of the P(HPMA/NVP) increased with increasing of P(HPMA) composition. The composition of P(HPMA/NVP) : 70/30 and the concentration of the crosslin- king agent of 0.5 wt % gave the optimum condition in the application to the contact lens. There were also adequate in the mechanical, refractive properties and in vivo test in the P(HPMA/ NVP): 70/30 system.

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말초신경 손상 후 재생과 관련된 세포적, 분자적 변화 (Cellular and molecular change including nerve regeneration after peripheral nerve injury)

  • 백수정;김동현;김진상
    • The Journal of Korean Physical Therapy
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    • 제12권3호
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    • pp.415-432
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    • 2000
  • In mammals. axotomy of peripheral nerve leads to a complex. These events include swelling of cell body, disappearance of Nissl substance. Proximal and distal axon undergoes a variable deriable degree of traumatic degeneration and wallerian degeneration, respectively. Nerve injury may result in cell death or regeneration. Molecular changes include proliferation of Schwann cells, upregulation of neurotropism, neural cell adhesion molecules and cytokine. Also growth cone plays an essential role in axon guidance through interaction of cytoskeleton. We review cellular and molecular events after nerve injury and describe nerve regeneration and associated proteins.

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옥테닐호박산나트륨 전분의 이화학적 특성 (Physicochemical Properties of Octenylsuccinated Corn Starch)

  • 정만곤;임번삼
    • 한국식품위생안전성학회지
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    • 제14권1호
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    • pp.84-89
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    • 1999
  • Octenylscuccinated corn starches prepared by reaction of corn starch with 1-octenylsuccinic anhydride(OSAn) and their degree of substitution (DS), reaction efficiency(RE), residual octenylsuccinic acid (OSA), and physicochemical properties were compared with those of the native corn starch. DS increased with increase of OSAn and RE was much nearly the same regardless of increased of OSAn. The content of residual of residual OSA was significantly lower than that of regulation of food additives. And as washing frequency of dispersion of the reactant was increased, the content of residual OSA of octenylsuccinated starch was decreased. Raid Visco-Analyzer initial pasting temperature and setback of octenylsuccinated starches decreased whereas peak viscosity and breakdown increased. When DS of octenylsuccinated starches increased, temperature of initial gelatinization of octenylscuccinated starches drastically decreased. The octenylsuccinated starches also formed clearer pastes. The solubility was much nearly the same regardless of increase of DS at 7$0^{\circ}C$ but the swelling power increased 1.2~1.7 times higher than that of native corn starch at 7$0^{\circ}C$. The water binding capacity of octenylsuccinated starches also decreased.

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Determination of Kinetic Parameters in Coal Weathering Processes

  • Yun, Yongseung
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 1993년도 추계학술발표회 초록집
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    • pp.31-36
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    • 1993
  • Three different methods were employed to measure the degree of aerial oxidation in coal and the resulting oxidation/weathering indices were applied to obtain kinetic parameters of aerial oxidation processes, The index (i.e., slurry pH, Free Swelling Index, weight gain) values were subjected to kinetic analysis based on power-law Arrhenius type reaction model. The results show that activation energy of the aerial oxidation in 20-29$0^{\circ}C$ is in the range of 12-16 ㎉/㏖ and the agreement among three techniques is remarkable. The first order kinetic model is suitable in describing low temperature aerial oxidation process, except in the FSI case where the zero order expression is the best one.

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현미첨가에 의한 백설기의 특성변화에 관한 연구 (Effect of Addition of Brown Rice flour on Quality of Backsulgies)

  • 최영선;김영아
    • 한국식품조리과학회지
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    • 제9권2호
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    • pp.67-73
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    • 1993
  • The effects of addition of brown rice flour on the Backsulgies were examined. We chose the addition ratio of brown rice flour as 0%, 50%, 100% along with the pilot study. The addition of brown rice flour did not make significant changes in water-binding capacity, swelling power and the degree of gelatinization. But the addition of brown rice flour had a delaying effect of retrogradation of Backsulgies by textural analysis. In sensory evaluation, the Backsulgi added brown rice flour 50% had the highest value in the overall quality of sensory characteristics. But there was no significant difference in the other sensory characteristics between the 50% and 0% added with. Therefore we concluded that the addition of brown rice flour on Backsulgies improve the sensory characteristics as well as delay the retrogradation and would be a good source of dietary fiber.

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Epichlorohydin으로 가교결합시킨 감자 전분의 이화학적 특성 (Physicochemical Properites of Potato Starches Crosslinked with Epichlorohydrin)

  • 김미라;이선자
    • 한국식품영양과학회지
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    • 제28권1호
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    • pp.132-139
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    • 1999
  • Physicochemical properties of the crosslinked potato starches of MDC(Molar Degree of Crosslinking) 0.137~3.333 treated with epichlorohydrin were examined. MDC increased proportionally as epichlorohydrin concentration increased. Water binding capacity increased but blue value decreased with increasing MDC. Gelatinization trends obtained from DSC thermograms and transmittance showed that the gelatinization temperature of the crosslinked potato starch was higher than that of native potato starch, but there was no significant difference among the crosslinked potato starches. Solubility and swelling power decreased with increasing MDC. X ray diffraction patterns and scanning electron micrographs showed that the crosslinking of starch did not affect the crystallinity and the granule shape of starch.

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