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1.
IEEE Trans Pattern Anal Mach Intell ; 45(4): 4109-4121, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35925849

RESUMO

The unprecedented success of deep convolutional neural networks (CNN) on the task of video-based human action recognition assumes the availability of good resolution videos and resources to develop and deploy complex models. Unfortunately, certain budgetary and environmental constraints on the camera system and the recognition model may not be able to accommodate these assumptions and require reducing their complexity. To alleviate these issues, we introduce a deep sensing solution to directly recognize human actions from coded exposure images. Our deep sensing solution consists of a binary CNN-based encoder network that emulates the capturing of a coded exposure image of a dynamic scene using a coded exposure camera, followed by a 2D CNN for recognizing human action in the captured coded exposure image. Furthermore, we propose a novel knowledge distillation framework to jointly train the encoder and the action recognition model and show that the proposed training approach improves the action recognition accuracy by an absolute margin of 6.2%, 2.9%, and 7.9% on Something 2-v2, Kinetics-400, and UCF-101 datasets, respectively, in comparison to our previous approach. Finally, we built a prototype coded exposure camera using LCoS to validate the feasibility of our deep sensing solution. Our evaluation of the prototype camera show results that are consistent with the simulation results.

2.
Bioorg Med Chem Lett ; 24(16): 3802-6, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25042255

RESUMO

Poly(ADP-ribose) polymerase (PARP) and poly(ADP-ribose) glycohydrolase (PARG) are enzymes responsible for catalyzing the formation and degradation of poly(ADP-ribose) (PAR) polymers, respectively. Activation of PARP has been shown to be involved in cell death induced by genotoxic stimuli. On the other hand, genetic disruption of PARG also leads to increased level of cell death by accumulation of PAR. Unlike PARP, where significant medicinal effort has been expended to identify potent inhibitors, PARG has been insufficiently investigated as a molecular therapeutic target. In this study, we report the design, synthesis, and biological evaluation of phenolic hydrazide hydrazones as potent PARG inhibitors. Compounds 3d, 3e, 5d, 5e, 8a, 8b and 8c showed their ability to inhibit the catalytic activity of PARG in vitro with IC50 values of 1.0, 2.1, 3.1, 3.2, 3.1, 2.8 and 1.6 µM, respectively.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Hidrazonas/farmacologia , Fenóis/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Glicosídeo Hidrolases/metabolismo , Hidrazonas/síntese química , Hidrazonas/química , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
3.
Breast Cancer ; 21(6): 738-47, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23456737

RESUMO

BACKGROUND: Triple-negative breast cancers (TNBC) are defined as not having amplification of the estrogen receptor, progesterone receptor, or epidermal growth factor receptor 2. Recovery of patients is, currently, severely limited after diagnosis of metastatic TNBC, with fewer than 30 % of patients surviving more than 5 years. The most effective therapy to date is chemotherapy, which has been unsuccessful because of lack of therapeutic targets for these aggressive cancers. To identify new molecular targets for TNBC, we have developed a novel method for drug discovery using active compounds for identification of pharmacodynamic biomarkers. METHODS: We used chemical informatics to design a small-molecule library with structural diversity. This library was used to screen for compounds that selectively inhibit proliferation of TNBC cell lines. Different gene-expression profiles in cell lines before and after the addition of selected compounds were analyzed and compared with those of control cells. RESULTS: We identified (E)-3-(3,4-dihydroxybenzylidene)benzofuran-2(3H)-one (DBBF) which specifically inhibited proliferation of a TNBC cell line, MDA-MB-468, with an IC50 of 2.4 µM. Microarray analysis identified several signaling pathways, including the irinotecan pathway, which changed specifically in the TNBC cell lines on addition of DBBF. CONCLUSION: We have developed a novel research strategy that involves screening of selective inhibitors of TNBC cell line proliferation that can be used for identification of pharmacodynamic biomarkers for TNBC. The discovery of new pathways by this technique should lead to the identification of new therapeutic targets for this aggressive cancer.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Bibliotecas de Moléculas Pequenas/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos/química , Benzofuranos/farmacologia , Compostos de Benzilideno/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Chalcona/análogos & derivados , Chalcona/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Humanos , Terapia de Alvo Molecular , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
4.
Int J Oncol ; 43(1): 219-27, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23612755

RESUMO

Signal transducer and activator of transcription (STAT) 3, a member of a family of DNA-binding molecules, is a potential target in the treatment of cancer. The highly phosphorylated STAT3 in cancer cells contributes to numerous physiological and oncogenic signaling pathways. Furthermore, a significant association between STAT3 signaling and glioblastoma multiforme stem-like cell (GBM-SC) development and maintenance has been demonstrated in recent studies. Previously, we reported a novel small molecule inhibitor of STAT3 dimerization, STX-0119, as a cancer therapeutic. In the present study, we focused on cancer stem-like cells derived from recurrent GBM patients and investigated the efficacy of STX-0119. Three GBM stem cell lines showed many stem cell markers such as CD133, EGFR, Nanog, Olig2, nestin and Yamanaka factors (c-myc, KLF4, Oct3/4 and SOX2) compared with parental cell lines. These cell lines also formed tumors in vivo and had similar histological to surgically resected tumors. STAT3 phosphorylation was activated more in the GBM-SC lines than serum-derived GB cell lines. The growth inhibitory effect of STX-0119 on GBM-SCs was moderate (IC50 15-44 µM) and stronger compared to that of WP1066 in two cell lines. On the other hand, the effect of temozolomide was weak in all the cell lines (IC50 53-226 µM). Notably, STX-0119 demonstrated strong inhibition of the expression of STAT3 target genes (c-myc, survivin, cyclin D1, HIF-1α and VEGF) and stem cell-associated genes (CD44, Nanog, nestin and CD133) as well as the induction of apoptosis in one stem-like cell line. Interestingly, VEGFR2 mRNA was also remarkably inhibited by STX-0119. In a model using transplantable stem-like cell lines in vivo GB-SCC010 and 026, STX-0119 inhibited the growth of GBM-SCs at 80 mg/kg. STX-0119, an inhibitor of STAT3, may serve as a novel therapeutic compound against GBM-SCs even in temozolomide-resistant GBM patients and has the potential for GBM-SC-specific therapeutics in combination with temozolomide plus radiation therapy.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Oxidiazóis/administração & dosagem , Quinolinas/administração & dosagem , Fator de Transcrição STAT3/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Fator 4 Semelhante a Kruppel , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Invest New Drugs ; 30(5): 1878-86, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21912888

RESUMO

Resveratrol (3, 4', 5-trihydroxy-trans-stilbene), a natural phytoalexin found in grapes and wine, has anti-proliferative activity on human-derived cancer cells. In our study, we used a conventional condensation reaction between aldehydes and amines to provide a number of aza-resveratrol (3, 4', 5-trihydroxy-trans- aza-stilbene) derivatives in an attempt to screen for compounds with resveratrol's action but with increased potency. Aza-resveratrol and its hydroxylated derivative (3, 4, 4', 5-tetrahydroxy-trans- aza-stilbene) showed a more enhanced anti-proliferative effect than resveratrol in an MCF-7 breast carcinoma cell line. To identify the cellular targets of the aza derivatives of resveratrol, we conjugated the latter aza-stilbene compound with epoxy-activated agarose and performed affinity purification. Macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, was identified as a major target protein in MCF-7 cell lysates using a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS). The aza-resveratrol and its hydroxylated derivative, but not resveratrol, were also found to be potent inhibitors of MIF tautomerase activity, which may be associated with their inhibitory effects on MIF bioactivity for cell growth.


Assuntos
Compostos Aza/farmacologia , Fatores Inibidores da Migração de Macrófagos/antagonistas & inibidores , Sequência de Aminoácidos , Compostos Aza/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Dados de Sequência Molecular , Resveratrol , Estilbenos/química
6.
Int J Oncol ; 38(5): 1245-52, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21369699

RESUMO

Signal transducer and activator of transcription (STAT)3, a member of a family of DNA-binding molecules mediating numerous physiological and oncogenic signaling pathways, is a novel target in cancer cells which show high phosphorylation of STAT3. Recently, we identified a novel small-molecule inhibitor of STAT3 dimerization, STX-0119, as a cancer therapeutic. We investigated the mechanisms responsible for the antitumor activity in vitro and in vivo through numerous biochemical and biological assays. Specifically, the effects of STX-0119 on target genes (c-myc, cyclin D1, survivin) and apoptosis induction were analyzed in tumors treated with STX-0119 in vivo. STX-0119 showed strong growth-inhibitory activity against a broad range of hematological cancer cell lines, particularly lymphomas. STX-0119 suppressed the growth of SCC3 cells, a human lymphoma cell line with highly activated STAT3, through apoptosis and down-regulation of STAT3 targets such as c-myc, cyclin D1, survivin and Bcl-xL. Notably, Tyr-705-phosphorylated STAT3 up-regulation was not significantly suppressed by STX-0119, as opposed to other STAT3 inhibitors. STX-0119 demonstrated potent antitumor effects in vivo in SCC3-bearing nude mice by way of the down-regulation of STAT3 target genes and induction of apoptosis in the tumors. Thus, STX-0119 may be a new type of STAT3 inhibitor exhibiting strong antitumor activity.


Assuntos
Antineoplásicos/farmacologia , Linfoma/tratamento farmacológico , Oxidiazóis/farmacologia , Quinolinas/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Linfoma/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação , Multimerização Proteica , Fator de Transcrição STAT3/química , Fator de Transcrição STAT3/fisiologia
7.
ACS Med Chem Lett ; 1(8): 371-5, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24900220

RESUMO

The signal transducer and activator of transcription 3 (STAT3) is considered to be an attractive therapeutic target for oncology drug development. We identified a N-[2-(1,3,4-oxadiazolyl)]-4-quinolinecarboxamide derivative, STX-0119, as a novel STAT3 dimerization inhibitor by a virtual screen using a customized version of the DOCK4 program with the crystal structure of STAT3. In addition, we used in vitro cell-based assays such as the luciferase reporter gene assay and the fluorescence resonance energy transfer-based STAT3 dimerization assay. STX-0119 selectively abrogated the DNA binding activity of STAT3 and suppressed the expression of STAT3-regulated oncoproteins such as c-myc and survivin in cancer cells. In contrast, a truncated inactive analogue, STX-0872, did not exhibit those activities. Oral administration of STX-0119 effectively abrogated the growth of human lymphoma cells in a SCC-3 subcutaneous xenograft model without visible toxicity. Structure-activity relationships of STX-0119 derivatives were investigated using the docking model of the STAT3-SH2 domain/STX-0119.

8.
Bioorg Med Chem Lett ; 18(1): 371-4, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17981031

RESUMO

The compound named Histidine-pyridine-histidine (HPH) is an oxygen-activating ligand derived from the structure of bleomycin. We synthesized HPH derivatives, namely HPH-1 to -8, and investigated their antiviral activities against herpes simplex virus type 1. HPH-8 showed potent antiviral activity with an EC50 of 15 microM, and relatively high cytotoxicity with a CC50 of 37 microM. In contrast, HPH-4 indicated a weaker antiviral activity with an EC50 of 79 microM, but exhibited a far more less cytotoxicity (CC50 500 microM). Other HPH derivatives showed no effects against antiviral activities and cytotoxicities.


Assuntos
Antivirais/química , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Histidina/análogos & derivados , Piridinas/química , Piridinas/farmacologia , Animais , Chlorocebus aethiops , Histidina/farmacologia , Humanos , Camundongos , Relação Estrutura-Atividade , Células Vero
9.
J Pharmacol Exp Ther ; 320(1): 47-55, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17050777

RESUMO

Anthraquinone spermine [N1-(anthraquinone-2-carbonyl)spermine; AQ343], anthraquinone homospermine [N1-(anthraquinone-2-carbonyl; AQ444], anthracene spermine [N1-(9-anthracenylmethyl)spermine; Ant343], and anthracene homospermine [N1-(9-anthracenylmethyl)homospermine; Ant444] were found to be potent antagonists of recombinant N-methyl-D-aspartate (NMDA) receptors (NRs). The effects of both anthraquinone (AQ)- and anthracene (Ant)-tetraamines were reversible and voltage-dependent. Results of experiments using mutant NR1 and NR2B subunits of NMDA receptor identified residues that influence block by AQ- and Ant-tetraamines. The results indicate that the polyamine tail is crucial for block by AQ- and Ant-tetraamines. Residues in the outer vestibule of the NR1 subunit were more strongly involved in block by AQ-and Ant-tetraamines than residues in the corresponding region of NR2B. Several amino acid residues in the inner vestibule, below the level of the selectivity filter of NR1 and NR2B, affected block by AQ444, Ant343, and Ant444, but they did not affect block by AQ343. AQ-tetraamines could permeate the channel at very negative membrane potentials when the narrowest constriction of the channel was expanded by replacing the Asn residue at Asn616 of NR1 and NR2B with Gly, whereas Ant-tetraamines did not easily pass through the channel, apparently because of differences in the relative position of the head groups on AQ- and Ant-polyamines.


Assuntos
Antagonistas de Aminoácidos Excitatórios/farmacologia , Poliaminas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Animais , Antracenos/farmacologia , Antraquinonas/farmacologia , Maleato de Dizocilpina/farmacologia , Feminino , Camundongos , Mutagênese Sítio-Dirigida , Relação Estrutura-Atividade
10.
Bioorg Med Chem Lett ; 15(8): 2065-8, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15808469

RESUMO

Isoaurostatin A (IAS-A) isolated from Thermomonospora alba showed weak inhibition against topoisomerase (topo) I (IC(50)=307microM). To get more strong inhibition, derivatives of IAS-A were prepared and their structure-activity relationships against topo I and II were investigated. The addition of hydroxyl group on aromatic rings increased the activities, 3-(3,4,5-trihydroxybenzylidene)-5-hydroxy-3H-benzofuran-2-one (IAS-9) showed strong inhibition (IC(50)=3microM) against topo I. And also, the increasing of hydroxyl group increased growth inhibition against a variety of cancer cells, and IAS-9 showed most potent inhibition. Unlike camptothecin and etoposide, IAS-9 neither stabilized DNA-topo cleavable complex nor intercalated into DNA, and it inhibited topo I and II noncompetitively. The inhibitory activities also increased by opening of lactone ring in the molecule of IAS-9.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , Inibidores da Topoisomerase I , Inibidores da Topoisomerase II , Benzofuranos/isolamento & purificação , Linhagem Celular Tumoral , DNA Topoisomerases Tipo I/fisiologia , DNA Topoisomerases Tipo II/fisiologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Inibidores do Crescimento/farmacologia , Células HeLa , Humanos , Relação Estrutura-Atividade
11.
J Steroid Biochem Mol Biol ; 93(1): 73-9, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15748835

RESUMO

The first aim of this study is to characterize the reduction of progesterone in rat liver. Progesterone was mainly reduced to 20alpha-hydroxyprogesterone in the cytosolic fraction of rat liver. The amount of 20alpha-hydroxyprogesterone formed from progesterone in the cytosolic fraction was significantly larger in the males than in the females and this enzyme reaction proceeded not only in the presence of NADPH, but also in the presence of NADH. Furthermore, we attempted to evaluate the inhibitory effects of 15 flavonoids on the NADPH-dependent reduction of progesterone to 20alpha-hydroxyprogesterone in liver cytosol of male rats. The order of the inhibitory potencies was luteolin>apigenin>quercetin>myricetin=fisetin=kaempferol. Other flavonoids exhibited lower inhibitory potencies. Energy-minimized molecular models demonstrated that a planar benzopyrone ring (A and C rings) with a coplanar phenyl ring (B ring) is a structural characteristic determining the inhibitory effects of flavonoids other than isoflavones.


Assuntos
Flavonoides/farmacologia , Hidroxiprogesteronas/metabolismo , Fígado/metabolismo , Progesterona/antagonistas & inibidores , Animais , Cromatografia Líquida de Alta Pressão , Citosol/metabolismo , Feminino , Flavonoides/química , Hidroxiprogesteronas/análise , Concentração Inibidora 50 , Fígado/efeitos dos fármacos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Conformação Molecular , Estrutura Molecular , NAD/metabolismo , NADP/metabolismo , Oxirredução , Progesterona/metabolismo , Ratos , Ratos Endogâmicos F344 , Fatores Sexuais , Relação Estrutura-Atividade , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo
12.
Toxicol Appl Pharmacol ; 202(1): 59-67, 2005 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-15589977

RESUMO

The Long-Evans Cinnamon (LEC) rat is a mutant strain that accumulates excessive tissue copper (Cu) and models the clinical symptoms and biological features of Wilson's disease in humans. We compared the effects of three metal chelating agents, N-benzyl-d-glucamine dithiocarbamate (BGD), d-penicillamine (D-PEN), and triethylenetetramine (TETA), on the biliary and urinary excretions of Cu using LEC rats. The animals were treated ip with each chelating agent (1 mmol/kg body weight) and then the bile and urine samples were collected for 3 h. Because single treatment with BGD markedly stimulated biliary excretion of Cu, the protective effect of repeated BGD injection on spontaneous hepatocellular damage was further examined. Separate groups received two weekly injections of BGD starting at 11 weeks of age and were compared to saline-injected controls. Serum alanine aminotransferase (ALT) activity and bilirubin level were significantly increased in control LEC rats by 19 weeks of age and histopathological analysis demonstrated extensive hepatic damage in these rats. However, repeated BGD injections prevented the increases in serum ALT and bilirubin and blocked the histopathological changes in the liver. Furthermore, although Cu rapidly accumulated in the liver, kidney, spleen, and serum of control LEC rats during the test period, repeated BGD injection largely prevented these increases. These results indicate that BGD treatment is effective in blocking excessive Cu accumulation in LEC rats that, in turn, provides protection from spontaneous liver damage.


Assuntos
Quelantes/farmacologia , Degeneração Hepatolenticular/tratamento farmacológico , Fígado/efeitos dos fármacos , Sorbitol/análogos & derivados , Sorbitol/farmacologia , Tiocarbamatos/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Cobre/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Degeneração Hepatolenticular/metabolismo , Degeneração Hepatolenticular/patologia , Humanos , Fígado/patologia , Ratos , Ratos Long-Evans
13.
Bioorg Med Chem Lett ; 14(7): 1669-72, 2004 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-15026047

RESUMO

o-, m-, p-Phenylenediamines having 2,3,4-trihydroxy, 3,4 dihydroxy, and 4-hydroxybenzoyl moieties were prepared and their inhibitory activities were measured against topoisomerase I and II. More hydroxy groups on two aromatic rings increased the activities. Bis(trihydroxybenzoyl)-o-phenylenediamide showed IC(50)=0.90 and 0.09 microM against topoisomerase I and II, respectively. Compounds with hydroxy groups protected by acetyl moiety still had the activities. Less hydroxy groups decreased their activities. Benzothiazole derivatives also indicated the activities.


Assuntos
Inibidores Enzimáticos/química , Inibidores da Topoisomerase I , Inibidores da Topoisomerase II , Ciclo Celular/efeitos dos fármacos , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Inibidores do Crescimento/química , Inibidores do Crescimento/farmacologia , Células HeLa , Humanos , Relação Estrutura-Atividade
14.
J Pharmacol Exp Ther ; 309(3): 884-93, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14764657

RESUMO

The effects of various anthraquinone polyamines (AQP) were studied at recombinant N-methyl-d-aspartate (NMDA) receptors expressed in Xenopus laevis oocytes. The AQP derivatives had different numbers of methylene groups between the NH(2) (or NH) groups in their spermidine-like tail. Thus, we termed these derivatives AQ33, AQ34, etc. All AQP derivatives inhibited responses of NR1/NR2 receptors in oocytes voltage-clamped at -70 mV, with IC(50) values between 4 and 22 microM. The block was strongly voltage-dependent. AQ34 and AQ33b inhibited responses of NR1/NR2 receptors but did not inhibit responses of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors expressed from GluR1 or GluR2(Q), indicating that AQ34 and AQ33b are preferential NMDA antagonists. Results of experiments using mutant NR1 and NR2 subunits identified residues that influence block by AQ34 and AQ33b. These residues are located in the outer vestibule at the selectivity filter/narrowest constriction of the channel and in the inner vestibule below the level of the selectivity filter. The results with mutant NR1 and NR2 subunits are consistent with the idea that NR1(Asn616) and NR2B(Asn616), but not NR2B(Asn615), make the narrowest constriction of NMDA channel.


Assuntos
Antagonistas de Aminoácidos Excitatórios/farmacologia , Oócitos/efeitos dos fármacos , Poliaminas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Aminoácidos/metabolismo , Animais , Antraquinonas/química , Antraquinonas/farmacologia , Antagonistas de Aminoácidos Excitatórios/química , Mutagênese Sítio-Dirigida , Oócitos/metabolismo , Poliaminas/química , Conformação Proteica , Receptores de AMPA/antagonistas & inibidores , Receptores de AMPA/química , Receptores de N-Metil-D-Aspartato/química , Relação Estrutura-Atividade , Xenopus laevis
15.
Life Sci ; 74(1): 29-36, 2003 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-14575810

RESUMO

When s-triazolo[3,4-a]phthalazine (Tri-P) was orally administered in rats, a more lipophilic metabolite M-1 than the parent compound was isolated from the urine. The metabolite M-1 was identified as 7-methylthio Tri-P by means of high resolution MS and two-dimensional NMR spectrometry. Furthermore, the 7-methylthio conjugate was generated from the parent compound Tri-P in isolated rat hepatocytes. Although the contribution of the intestinal microflora to the formation of methylthio metabolite has been pointed out so far, the limited data in this study lead us to conclude that the liver plays a role in all metabolic reactions of Tri-P to its 7-methylthio conjugate in rats.


Assuntos
Ansiolíticos/farmacologia , Hepatócitos/química , Ftalazinas/farmacologia , Triazóis/farmacologia , Animais , Ansiolíticos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Masculino , Ftalazinas/isolamento & purificação , Ratos , Ratos Wistar , Triazóis/isolamento & purificação
16.
J Org Chem ; 61(12): 4125-4129, 1996 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-11667293

RESUMO

Hydrazinoethanols 1 were reacted with aldehydes 2 and 6 and glutaraldehyde (14) in aqueous solution to give dioxatetraazaperhydroanthracenes 3, 7, 12, and 13 and -perylenes 15 in yields of 19-88 and 42-72%, respectively. Compounds 3, 7, 12, and 15 were deduced by (13)C-NMR spectra to have two C(2) symmetry axes, while compound 12 was shown to have a symmetry axis by X-ray crystallography. The most favorable stereoisomers were consistent with predictions obtained by the semiempirical molecular orbital method AM1. The structure of compound 15 was confirmed by X-ray crystallography.

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