• Title/Summary/Keyword: S/R

Search Result 29,863, Processing Time 0.075 seconds

New candidate for skin depigmentation: The inhibitory effect and cytotoxicity of small molecule compounds at in vitro cell culture

  • Rho, H.S;Kim, K.J.;Hwang, J.S.;H.J., Shin;Chang, H.K.;Chang, I.S.;Lee, O.S.
    • Proceedings of the SCSK Conference
    • /
    • 2003.09b
    • /
    • pp.174-183
    • /
    • 2003
  • To obtain effective and safe topical depigmenting agents, we synthesized hydroxybenzoates, alkoxybenzoates, and 3,4,5-trimethoxycinnamate containing a thymol moiety and screened then for high-level inhibitory activity against melanin synthesis. Among them, 5-methyl-2-(methylethyl)phenyl (2Ε)-3-(3,4,5-trimethoxyphenyl)prop-2-enoate (Melasolv)$^{TM}$ 4h, showed the most potent depigmenting effect ($IC_{50}$/ = 10$\mu$M) with low cytotoxicity ($IC_{50}$/ = 200$\mu$M). To find the inhibition mechanism of our candidate, various in vitro tests were performed such as DPPH assay, tyrosinase activity in mushroom or in culture cell and expression of tyrosinase, TRP-l and TRP-2. The result of this study suggested that 4h inhibited melanin synthesis by reducing the expression of tyrosinase and TRP-l at the transcriptional level in melan-a melanocytes.s.

  • PDF

Development of Novel Pyrone Derivative Retaining Retinoidal Anti-aging Activity with Low Skin Irritation

  • Rho, H.S;Kim, D.H;Kim, S.N;Kim, S.J;Chang, I.S;Kang, H.H;Lee, O.S
    • Proceedings of the SCSK Conference
    • /
    • 2003.09b
    • /
    • pp.184-191
    • /
    • 2003
  • New pyranone derivative, 2-((3E)-4(2H, 3H, -benzo[3, 4-d] 1, 3-dioxolan-5-yl)-2-oxo-but-3-enyloxy)-5-hydroxy-4H-pyran-4-one (Seletinoid $G^{TM}$), was designed as a novel retinoid on the assumption that the pyranone ring may mimic the carboxylic acid moiety in retinoid structure. The enolic hydroxy of pyranone at five position was easily deprotonated to form an enolate. The role of enolate was similar to that of carboxylic acid. To evaluate the value of Seletinoid G as an anti-aging ingredient, various tests were performed for example inhibitory effect for MMP-l expression, anti-oxidative activity, procollagen synthesis in hairless mouse and primary skin irritation. The result of this study suggested that our new synthetic retinoid could be used as a safe material for anti-aging cosmetics.

  • PDF

Epistatic Relationships of Two Regulatory Factors During Heterocyst Development

  • Kim, Young-Saeng;Kim, Il-Sup;Shin, Sun-Young;Kim, Hyun-young;Kang, Sung-Ho;Yoon, Ho-Sung
    • ALGAE
    • /
    • v.24 no.2
    • /
    • pp.85-91
    • /
    • 2009
  • The filamentous cyanobacterium Anabaena sp. Strain PCC 7120 produces a developmental patten of single hete- rocysts separated by approximately 10 vegetative cells. Heterocysts differentiate from vegetative cells and are spe- cialized for nitrogen fixation. The patS gene, which encodes a small peptide that inhibits heterocyst differentiation, is expressed in proheterocysts and plays a critical role in establishing the heterocyst pattem. Another key regulator of heterocyst development is the hetR gene. hetR mutants fail to produce heterocysts and extra copies of hetR on a plas- mid cause a multiple contiguous heterocyst phenotype. To elucidate the relationship between these two counter act- ing factors in the genetic regulatory pathway during heterocyst differentiation, the expression patterns of a patS-gfp and a hetR-gfp fusion were examined in a patS deletion and a hetR deletion strain. The results, in combination with the result from a hetR and patS double deletion strain, suggest patS and hetR are mutually antagonistic and the bal- ance between these two factors in tow different cell types (heterocysts and vegetative cells) may be critical during the decision making process on their cell fates.

Comparison of Human Sodium/Iodide Symporter (hNIS) Gene Expressions between Lentiviral and Adenoviral Vectors in Rat Mesenchymal Stem Cells (렌티바이러스와 아데노바이러스를 통하여 쥐의 중간엽줄기세포에 사람 나트륨/옥소 공동수송체 유전자를 전달하였을 때의 발현성능 비교)

  • Park, So-Yeon;Kim, Sung-Jin;Lee, Won-Woo;Lee, Heui-Ran;Kim, Hyun-Joo;Chung, June-Key;Kim, Sang-Eun
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.42 no.5
    • /
    • pp.394-400
    • /
    • 2008
  • Purpose: Quantitative comparison of transgene expression within stem cells between lentivirus and adenovirus-mediated delivery systems has not been reported. Here, we evaluated the human sodium iodide symporter (hNIS) gene expression in rat mesenchymal stem cell (rMSC) transduced by lentivirus or adenovirus, and compared the hNIS expression quantitatively between the two delivery systems. Materials and Methods: Lentiviral-mediated hNIS expressing rMSC (lenti-hNIS-rMSC) was constructed by cloning hNIS gene into pLenti6/UbC/V5-DEST (Invitrogen) to obtain pLenti-hNIS, transducing rMSC with the pLenti-hNIS, and selecting with blasticidin for 3 weeks. Recombinant adenovirus expressing hNIS gene (Rad-hNIS) was produced by homologous recombination and transduction efficiency of Rad-hNIS into rMSC evaluated by Rad-GFP was $19.1{\pm}4.7%$, $54.0{\pm}6.4%$, $85.7{\pm}8.7%$, and $98.4{\pm}1.3%$ at MOI 1, 5, 20, and 100, respectively. The hNIS expressions in lenti-hNIS-rMSC or adeno-hNIS-rMSC were assessed by immunocytochemistry, western blot, and 1-125 uptake. Results: Immunocytochemistry and western blot analyses revealed that hNIS expressions in lenti-hNIS-rMSC were greater than those in adeno-hNIS-rMSC at MOI 20 but lower than at MOI 50. However in vitro 1-125 uptake test demonstrated that iodide uptake in lenti-hNIS-rMSC ($29,704{\pm}6,659\; picomole/10^6\;cells$) was greater than that in adeno-hNIS-rMSC at MOI 100 ($6,168{\pm}2,134\;picomole/10^6\;cells$). Conclusion: Despite lower amount of expressed protein, hNIS function in rMSC was greater by lentivirus than by adenovirus mediated expression. Stem cell tracking using hNIS as a reporter gene should be conducted in consideration of relative vector efficiency for transgene expression.

Flow Resistance and Modeling Rule of Fishing Nets 4. Flow Resistance of Trawl Nets (그물어구의 유수저항과 모형수칙 4. 트롤그물의 유수저항)

  • KIM Dae-An
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.30 no.5
    • /
    • pp.691-699
    • /
    • 1997
  • In order to find out the properties in flow resistance of trawlR=1.5R=1.5\;S\;v^{1.8}\;S\;v^{1.8} nets and the exact expression for the resistance R (kg) under the water flow of velocity v(m/sec), the experimental data on R obtained by other, investigators were pigeonholed into the form of $R=kSv^2$, where $k(kg{\cdot}sec^2/m^4)$ was the resistance coefficient and $S(m^2)$ the wall area of nets, and then k was analyzed by the resistance formular obtained in the previous paper. The analyzation produced the coefficient k expressed as $$k=4.5(\frac{S_n}{S_m})^{1.2}v^{-0.2}$$ in case of bottom trawl nets and as $$k=5.1\lambda^{-0.1}(\frac{S_n}{S_m})^{1.2}v^{-0.2}$$ in midwater trawl nets, where $S_m(m^2)$ was the cross-sectional area of net mouths, $S_n(m^2)$ the area of nets projected to the plane perpendicular to the water flow and $\lambda$ the representitive size of nettings given by ${\pi}d^2/2/sin2\varphi$ (d : twine diameter, 2l: mesh size, $2\varphi$ : angle between two adjacent bars). The value of $S_n/S_m$ could be calculated from the cone-shaped bag nets equal in S with the trawl nets. In the ordinary trawl nets generalized in the method of design, however, the flow resistance R (kg) could be expressed as $$R=1.5\;S\;v^{1.8}$$ in bottom trawl nets and $$R=0.7\;S\;v^{1.8}$$ in midwater trawl nets.

  • PDF

Comparison of Smooth-Rough Form Variation and Antibiotic Susceptibility of Escherichia coli and Clostridium perfringens Isolates from Chickens, Pigs and Cattle (닭, 돼지 및 소에서 분리한 대장균과 Clostridium perfringens의 S-R변이와 항생제의 감수성 비교)

  • ;Takashi Uemura
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.11 no.2
    • /
    • pp.97-103
    • /
    • 2001
  • Acriflavine 시험법을 이용해서 수종의 화학물질을 첨가한 배지에 대장균과 Clostridium perfringens을 배양하여 변이를 유도한 후, S-R 변이와 변이 후의 항생제에 대한 감수성을 조사한 결과, 화학물질에 대한 S-R변이의 경우, 대장균은 mercuric chloride, cysteine, caffeine, glucose, nicotine 등의 순으로 나타났고, C. perfringens는 mercuric chloride, nicotine, caffeine, cystein, glucose 등의 순으로 나타났으며 양자 공히 mercuric chloride가 가장 감수성이 높았다. 항생제에 대한 S-R 변이 후의 감수성은 대장균과 C. perfingens가 공히 S-R변이 후에는 감수성이 일반적으로 저하되는 경향이었다.

  • PDF

Intermediate Subrings of Normalizing Extensions

  • Min, Kang-Joo
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.7 no.1
    • /
    • pp.87-95
    • /
    • 1994
  • Relationships between the prime ideals of a ring R and of a normalizing extension S have been studied by several authors. Relationships between the prime ideals of a ring R and of an intermediate normalizing extension T also have studied by several authors where $R{\subset}T{\subset}S$. In this note, some relationships between prime ideals of T and S are studied.

  • PDF