• 제목/요약/키워드: Small molecules

검색결과 669건 처리시간 0.038초

Quorum Sensing Regulation of Biofilm Formation by Periodontal Pathogens

  • Choi, Bong-Kyu
    • International Journal of Oral Biology
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    • 제43권4호
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    • pp.171-175
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    • 2018
  • Quorum sensing (QS) is a cell density-dependent communication mechanism between bacteria through small signaling molecules. When the number of QS signaling molecules reaches a threshold, they are transported back into the cells or recognized by membrane-bound receptors, triggering gene expression which affects various phenotypes including bioluminescence, virulence, adhesion, and biofilm formation. These phenotypes are beneficial for bacterial survival in harsh environments. This review summarizes the application of QS inhibitors for control of biofilm formation and virulence expression of periodontal pathogens.

G Protein-Coupled Receptors: Molecular Organization and Regulatory Mechanisms

  • Caron, Marc G.
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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    • pp.82-87
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    • 1994
  • Signal transduction through G protein-coupled receptors comprises three functional components, a receptor, a G protcin and a effector protein. Work over the last sevcral ycars has led to the characterization or virtually all of the components or these systems. what has come out or those studies is that these mechanisms of signal transduction are pervasive in nature being found in mammalian and avian species, as well as lower organisms such as yeast and slime mold. It is known that G protein-coupled receptors mediate the action of such diverse molecules such as small hormones and neurotransmitters, small peptide molecules as well as glycoprotein hormones and various sensory perceptions such as light, olfaction and most likely taste.

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방향족 치환기의 소수성 사슬을 갖는 양이온 계면활성제의 합성과 이의 물리화학적 특성 연구 (Synthesis and Their Physical Properties of Cationic Surfactants bearing Hydrophobic Chains of Aromatic Subtituents)

  • 안범수
    • 한국응용과학기술학회지
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    • 제30권3호
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    • pp.380-386
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    • 2013
  • N,N,N-Trimethyl-10-nitrophenoxy decylammonium bromide (N10TAB) and N,N,N,N-Tetramethyl-bis-[10-nitrophenoxy decyl]-1,6-hexanediammonium dibromide (N10-6-10N), bearing aromatic nitrophenoxy group in the end of their hydrophobic chains have been prepared, and their properties in aqueous solutions have been studied by conductivity and H-NMR spectroscopy. Below the critical micelle concentration N10-6-10N form premicelle with two or three surfactant molecules. Beyond the critical micelle concentration two molecules have strong self-aggregation ability and form micelles of rather small size and with small aggregation numbers. H-NMR at different concentrations give the informations on the environmental changes of the surfactants on their micellization progress.

Statistical Considerations in the Design of Biosimilar Cancer Clinical Trials

  • Ahn, Chul;Lee, Seung-Chun
    • 응용통계연구
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    • 제24권3호
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    • pp.495-503
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    • 2011
  • When a patent of an innovative (brand-name) small-molecule drug expires, generic copies of the innovative drug may be marketed if their therapeutic equivalence to the innovative drug has been shown. The small-molecule drugs are considered therapeutically equivalent and can be used interchangeably if two drugs are shown to be pharmaceutically equivalent with identical active substance and bioequivalent with comparable pharmacokinetics in a crossover clinical trial. However, the therapeutic equivalence paradigm cannot be applied to biosimilars since the active ingredients of biosimilars are huge molecules with complex and heterogeneous structures, and these molecules are difficult to replicate in every detail. The European Medicine Agency(EMEA) has introduced a regulatory biosimilar pathway which mandates clinical trials to show therapeutic equivalence. In this paper, we discuss statistical considerations in the design and analysis of biosimilar cancer clinical trials.

Avidin Induced Silver Aggregation for SERS-based Bioassay

  • Sa, Youngjo;Chen, Lei;Jung, Young Mee
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3681-3685
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    • 2012
  • We developed a simple and effective method for the SERS-based detection of protein-small molecule complexes and label-free proteins using avidin-induced silver aggregation. Upon excitation with light of the appropriate wavelength (633 and 532 nm), the aggregated silver nanoparticles generate a strong electric field that couples with the resonance of the molecules (atto610 and cytochrome c), increasing the characteristic signals of these molecules and resulting in sensitive detection. The detection limit of biotin with the proposed method is as low as 48 ng/mL. The most important aspect of this method is the induction of silver aggregation by a protein (avidin), which makes the silver more biocompatible. This technique is very useful for the detection of protein-small molecule complexes.

Towards Designing Environmentally Stable Conjugated Polymers with very Small Band-Gaps

  • Hong, Sung Y.;Kim, Sung C.
    • Bulletin of the Korean Chemical Society
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    • 제24권11호
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    • pp.1649-1654
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    • 2003
  • We have investigated substituent effect on the stabilization energies, and nucleus-independent chemical shifts of pentafulvalenes and on the electronic structures of the corresponding polypentafulvalenes to design environmentally stable semiconductive or conductive polymers. Geometrical optimizations of the molecules were carried out at the density functional level of theory with B3LYP hybrid functional and 6-311+G(d) basis set. Stabilization energies were estimated using isodesmic and homodesmotic reactions. As a criterion of aromaticity nucleus-independent chemical shifts of the molecules were computed using GIAO approach. For the polymers the geometrical parameters were optimized through AM1 band calculations and the electronic structures were obtained through modified extended Huckel band calculations. It is found that strong electronwithdrawing substituents increase isodesmic and homodesmotic stabilization energies of pentafulvalene, though it does not increase the aromaticity. Nitro-substituted pentafulvalene is estimated to have stabilization energy as much as azulene. However, substitution either with electron-donating groups or with electronwithdrawing groups does not significantly affect the electronic structures of polypentafulvalene and poly (vinylenedioxypentafulvalene).

Tetrazine/DPP를 갖는 유기태양전지용 신규 단분자에 관한 연구 (Small Molecules Based on Tetrazine or DPP for OPV Application)

  • 김진아;현지나;이경균;이성구;임은희
    • 응용화학
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    • 제15권2호
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    • pp.105-108
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    • 2011
  • Organic photovoltaic cells (OPVs) have attracted considerable attention due to their low cost, light-weight and flexible characteristics. Small molecules have advantages of well-defined structure and easy synthesis. In this work, new tetrazine, DPP, and furan-based oligomers for organic solar cell were synthesized by Suzuki coupling reaction. The structures were confirmed by NMR and optical and electronic properties were investigated by UV-vis absorption.

Machine learning Anti-inflammatory Peptides Role in Recent Drug Discovery

  • Subathra Selvam
    • 통합자연과학논문집
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    • 제17권1호
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    • pp.21-30
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    • 2024
  • Several anti-inflammatory small molecules have been found in the process of the inflammatory response, and these small molecules have been used to treat some inflammatory and autoimmune diseases. Numerous tools for predicting anti-inflammatory peptides (AIPs) have emerged in recent years. However, conducting experimental validations in the lab is both resource-intensive and time-consuming. Current therapies for inflammatory and autoimmune disorders often involve nonspecific anti-inflammatory drugs and immunosuppressants, often with potential side effects. AIPs have been used in treating inflammatory illnesses like Alzheimer's disease and can limit the expression of inflammatory promoters. Recent advances in adverse incident predictions (AIPs) have been made, but it is crucial to acknowledge limitations and imperfections in existing methodologies.

PHOTOFRAGMENT IMAGINGOF SMALL MOLECULES

  • Lee, Kyoung-Seok;Lim, Jung-Sik;Ahn, Doo-Sik;Kim, Sang-Kyu
    • 한국광과학회:학술대회논문집
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    • 한국광과학회 2005년도 제12회 학술대회 논문초록
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    • pp.100-100
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    • 2005
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Identification of small molecules that inhibit the histone chaperone Asf1 and its chromatin function

  • Seol, Ja-Hwan;Song, Tae-Yang;Oh, Se Eun;Jo, Chanhee;Choi, Ahreum;Kim, Byungho;Park, Jinyoung;Hong, Suji;Song, Ilrang;Jung, Kwan Young;Yang, Jae-Hyun;Park, Hwangseo;Ahn, Jin-Hyun;Han, Jeung-Whan;Cho, Eun-Jung
    • BMB Reports
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    • 제48권12호
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    • pp.685-690
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    • 2015
  • The eukaryotic genome is packed into chromatin, which is important for the genomic integrity and gene regulation. Chromatin structures are maintained through assembly and disassembly of nucleosomes catalyzed by histone chaperones. Asf1 (anti-silencing function 1) is a highly conserved histone chaperone that mediates histone transfer on/off DNA and promotes histone H3 lysine 56 acetylation at globular core domain of histone H3. To elucidate the role of Asf1 in the modulation of chromatin structure, we screened and identified small molecules that inhibit Asf1 and H3K56 acetylation without affecting other histone modifications. These pyrimidine-2,4,6-trione derivative molecules inhibited the nucleosome assembly mediated by Asf1 in vitro, and reduced the H3K56 acetylation in HeLa cells. Furthermore, production of HSV viral particles was reduced by these compounds. As Asf1 is implicated in genome integrity, cell proliferation, and cancer, current Asf1 inhibitor molecules may offer an opportunity for the therapeutic development for treatment of diseases.