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1.
Polymers (Basel) ; 14(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35567014

RESUMO

We experimentally demonstrate the direct visualization of ultraviolet (UV) light using flexible polymer composite films consisting of crystalline organic tris-(8-hydroxyquinoline) aluminum (Alq3) micro-rods and polydimethylsiloxane (PDMS). The representative organic mono-molecule Alq3, which is a core material of organic light-emitting diodes, was used to detect light in the invisible UV region and visualize photoluminescence (PL). Alq3 shows absorption in the UV region and light-emitting characteristics in the green region, making it an optimal material for UV visualization because of its large Stokes transition. Crystalline Alq3 micro-rods were fabricated in a deionized water solution through a sequential process of reprecipitation and self-assembly. Highly bright photoluminescence was observed on the highly crystalline Alq3 micro-rods under UV light excitation, indicating that the crystalline structures of Alq3 molecules affect the visible emission decay of excitons. The Alq3 micro-rods were manufactured as flexible polymer composite films using a PDMS solution to observe UV photodetector characteristics according to UV intensity, and it was confirmed that the intensity of the fine UV light reaching the earth's surface can be visualized by making use of this UV photodetector.

2.
Bioorg Med Chem ; 22(2): 892-905, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24369839

RESUMO

A novel series of 2-amino-1,3,5-triazines bearing a tricyclic moiety as heat shock protein 90 (Hsp90) inhibitors is described. Molecular design was performed using X-ray cocrystal structures of the lead compound CH5015765 and natural Hsp90 inhibitor geldanamycin with Hsp90. We optimized affinity to Hsp90, in vitro cell growth inhibitory activity, water solubility, and liver microsomal stability of inhibitors and identified CH5138303. This compound showed high binding affinity for N-terminal Hsp90α (Kd=0.52nM) and strong in vitro cell growth inhibition against human cancer cell lines (HCT116 IC50=0.098µM, NCI-N87 IC50=0.066µM) and also displayed high oral bioavailability in mice (F=44.0%) and potent antitumor efficacy in a human NCI-N87 gastric cancer xenograft model (tumor growth inhibition=136%).


Assuntos
Benzopiranos/farmacologia , Desenho de Fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Neoplasias Experimentais/tratamento farmacológico , Triazinas/farmacologia , Administração Oral , Animais , Benzopiranos/administração & dosagem , Benzopiranos/síntese química , Disponibilidade Biológica , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HCT116 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade , Triazinas/administração & dosagem , Triazinas/síntese química
3.
Bioorg Med Chem Lett ; 21(19): 5778-83, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21875802

RESUMO

Heat shock protein 90 (Hsp90) is a molecular chaperone which regulates maturation and stabilization of its substrate proteins, known as client proteins. Many client proteins of Hsp90 are involved in tumor progression and survival and therefore Hsp90 can be a good target for developing anticancer drugs. With the aim of efficiently identifying a new class of orally available inhibitors of the ATP binding site of this protein, we conducted fragment screening and virtual screening in parallel against Hsp90. This approach quickly identified 2-aminotriazine and 2-aminopyrimidine derivatives as specific ligands to Hsp90 with high ligand efficiency. In silico evaluation of the 3D X-ray Hsp90 complex structures of the identified hits allowed us to promptly design CH5015765, which showed high affinity for Hsp90 and antitumor activity in human cancer xenograft mouse models.


Assuntos
Antineoplásicos/síntese química , Benzopiranos/química , Benzopiranos/síntese química , Simulação por Computador , Desenho de Fármacos , Descoberta de Drogas/métodos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Triazinas/química , Triazinas/síntese química , Adenosina Trifosfatases/metabolismo , Administração Oral , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Benzopiranos/metabolismo , Benzopiranos/farmacocinética , Relação Dose-Resposta a Droga , Escherichia coli/genética , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Neoplasias/tratamento farmacológico , Reprodutibilidade dos Testes , Relação Estrutura-Atividade , Ressonância de Plasmônio de Superfície , Triazinas/metabolismo , Triazinas/farmacocinética , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Protein Pept Lett ; 14(8): 800-3, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17979822

RESUMO

A lectin that induces hemagglutination activity in mouse and rabbit erythrocytes has been purified from the hemolymph of the marine hair crab Erimacrus isenbeckii. The results of SDS-PAGE, gel-filtration, affinity and anion-exchange chromatography indicate that this lectin, designated EIL (E. isenbeckii lectin), was successfully purified as a single protein, and comprises a mixture of a major (90%) dimeric and a minor (10%) oligomeric protein with a molecular mass of 116 kDa, with covalent linking between two subunits of 62 and 54 kDa. The activity was maximal at pH 5.6-8.0 and at temperatures below 50 degrees C. The N-terminal amino acid sequences were determined, and these differed greatly from those of other reported lectins from invertebrates, vertebrates, or plants. EIL binds with high specificities to both the O-acetylsialic acid and mannose that are present in bacterial pathogens, which suggests that EIL can act as a defense protein against infection in this crab.


Assuntos
Hemolinfa/química , Lectinas/isolamento & purificação , Sequência de Aminoácidos , Animais , Braquiúros , Eletroforese em Gel de Poliacrilamida , Hemaglutinação/efeitos dos fármacos , Manose/farmacologia , Dados de Sequência Molecular , Peso Molecular , Ribonucleases/antagonistas & inibidores
5.
Protein Pept Lett ; 11(6): 563-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15579126

RESUMO

The mushroom Paecilomyces japonica, grown on the silkworm larvae, has been used in Asia as a nutraceutical, tea, and Chinese medicine. In the present study, a sialic acid-specific lectin has been purified from the mushroom P. japonica using affinity chromatography on a fetuin-agarose column. Electrophoretical analyses indicated that this lectin, designated P. japonica agglutinin (PJA), is an acidic protein with a molecular mass of 16 kDa, and has no intermolecular disulfide bonds. PJA induced hemagglutination activity in human ABO, mouse, rat, and rabbit erythrocytes. This activity was inhibited by sialic acid and sialoglycoproteins, but not by any other carbohydrates. PJA was stable at pH 4.0-8.0, and at temperatures below 55 degrees C. The activity of PJA was independent of EDTA and divalent cations. In addition, PJA exerts cytotoxic effects on the following cancer cell lines: human stomach cancer SNU-1, human pancreas cancer AsPc-1, and human breast cancer MDA-MB-231.


Assuntos
Hemaglutinação/fisiologia , Paecilomyces/metabolismo , Lectinas de Plantas/metabolismo , Animais , Eletroforese em Gel de Poliacrilamida , Eritrócitos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Ácido N-Acetilneuramínico/metabolismo , Lectinas de Plantas/toxicidade , Coelhos , Ratos , Temperatura
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