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1.
J Med Chem ; 64(18): 13410-13428, 2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-34499493

RESUMO

Retinoic acid receptor-related orphan receptor γ (RORc, RORγ, or NR1F3) is the nuclear receptor master transcription factor that drives the function and development of IL-17-producing T helper cells (Th17), cytotoxic T cells (Tc17), and subsets of innate lymphoid cells. Activation of RORγ+ T cells in the tumor microenvironment is hypothesized to render immune infiltrates more effective at countering tumor growth. To test this hypothesis, a family of benzoxazines was optimized to provide LYC-55716 (37c), a potent, selective, and orally bioavailable small-molecule RORγ agonist. LYC-55716 decreases tumor growth and enhances survival in preclinical tumor models and was nominated as a clinical development candidate for evaluation in patients with solid tumors.


Assuntos
Antineoplásicos/uso terapêutico , Benzoxazinas/uso terapêutico , Neoplasias/tratamento farmacológico , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Propionatos/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Benzoxazinas/síntese química , Benzoxazinas/farmacocinética , Feminino , Macaca fascicularis , Masculino , Camundongos Endogâmicos C57BL , Estrutura Molecular , Propionatos/síntese química , Propionatos/farmacocinética , Ratos Sprague-Dawley , Relação Estrutura-Atividade
3.
Oncoimmunology ; 5(12): e1254854, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28123897

RESUMO

RORγt is the key transcription factor controlling the development and function of CD4+ Th17 and CD8+ Tc17 cells. Across a range of human tumors, about 15% of the CD4+ T cell fraction in tumor-infiltrating lymphocytes are RORγ+ cells. To evaluate the role of RORγ in antitumor immunity, we have identified synthetic, small molecule agonists that selectively activate RORγ to a greater extent than the endogenous agonist desmosterol. These RORγ agonists enhance effector function of Type 17 cells by increasing the production of cytokines/chemokines such as IL-17A and GM-CSF, augmenting expression of co-stimulatory receptors like CD137, CD226, and improving survival and cytotoxic activity. RORγ agonists also attenuate immunosuppressive mechanisms by curtailing Treg formation, diminishing CD39 and CD73 expression, and decreasing levels of co-inhibitory receptors including PD-1 and TIGIT on tumor-reactive lymphocytes. The effects of RORγ agonists were not observed in RORγ-/- T cells, underscoring the selective on-target activity of the compounds. In vitro treatment of tumor-specific T cells with RORγ agonists, followed by adoptive transfer to tumor-bearing mice is highly effective at controlling tumor growth while improving T cell survival and maintaining enhanced IL-17A and reduced PD-1 in vivo. The in vitro effects of RORγ agonists translate into single agent, immune system-dependent, antitumor efficacy when compounds are administered orally in syngeneic tumor models. RORγ agonists integrate multiple antitumor mechanisms into a single therapeutic that both increases immune activation and decreases immune suppression resulting in robust inhibition of tumor growth. Thus, RORγ agonists represent a novel immunotherapy approach for cancer.

4.
J Pharmacol Exp Ther ; 351(2): 298-307, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25125579

RESUMO

T-cell activation requires increased ATP and biosynthesis to support proliferation and effector function. Most models of T-cell activation are based on in vitro culture systems and posit that aerobic glycolysis is employed to meet increased energetic and biosynthetic demands. By contrast, T cells activated in vivo by alloantigens in graft-versus-host disease (GVHD) increase mitochondrial oxygen consumption, fatty acid uptake, and oxidation, with small increases of glucose uptake and aerobic glycolysis. Here we show that these differences are not a consequence of alloactivation, because T cells activated in vitro either in a mixed lymphocyte reaction to the same alloantigens used in vivo or with agonistic anti-CD3/anti-CD28 antibodies increased aerobic glycolysis. Using targeted metabolic (13)C tracer fate associations, we elucidated the metabolic pathway(s) employed by alloreactive T cells in vivo that support this phenotype. We find that glutamine (Gln)-dependent tricarboxylic acid cycle anaplerosis is increased in alloreactive T cells and that Gln carbon contributes to ribose biosynthesis. Pharmacological modulation of oxidative phosphorylation rapidly reduces anaplerosis in alloreactive T cells and improves GVHD. On the basis of these data, we propose a model of T-cell metabolism that is relevant to activated lymphocytes in vivo, with implications for the discovery of new drugs for immune disorders.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Isoantígenos/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Antígenos CD28/imunologia , Complexo CD3/imunologia , Ciclo do Ácido Cítrico/imunologia , Feminino , Glutamina/metabolismo , Glicólise/imunologia , Doença Enxerto-Hospedeiro/metabolismo , Camundongos , Fosforilação Oxidativa , Ribose/biossíntese
5.
Am J Obstet Gynecol ; 208(6): 462.e1-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23474428

RESUMO

OBJECTIVE: The objective of the study was to investigate whether vector velocity imaging (VVI), a non-Doppler speckle tracking ultrasound technology, is feasible in twin pregnancies and can aid management of twin-twin transfusion syndrome (TTTS). STUDY DESIGN: Twenty-seven women pregnant with monochorionic diamniotic twins affected by TTTS and 28 monochorionic pregnancies that did not develop TTTS were included in a prospective case-control study at a fetal medicine center. Fetal echocardiograms were recorded with dummy electrocardiography to retain original frame rates when exported for offline speckle tracking analysis using Syngo-VVI software (Siemens Corp, Munich, Germany). Right and left ventricular (LV) free wall Lagrangian strain was measured from the original coordinates. Within-twin pair ventricular strain differences including relationship to Quintero staging and response to laser therapy for TTTS were analyzed by Wilcoxon signed-rank test. RESULTS: The VVI strain measurements could be analyzed in 182 of 200 TTTS and 96 of 112 non-TTTS control ventricles. Within-pair strain was concordant in non-TTTS controls. Recipient LV strain was reduced at all Quintero stages compared with donors (P < .01). Recipient right ventricular strain was reduced only in stages 3 and 4 (P < .01). Strain improved at a median of 2 weeks following successful laser therapy. Intertwin differences in strain were independent of weight discordance. CONCLUSION: Recipient LV strain is reduced in stages 1 and 2 TTTS. Within-pair strain discordance may distinguish early TTTS from growth discordance and guide timing of and management following treatment.


Assuntos
Transfusão Feto-Fetal/fisiopatologia , Ventrículos do Coração/fisiopatologia , Gêmeos Monozigóticos , Ultrassonografia Pré-Natal/métodos , Adulto , Estudos de Casos e Controles , Ecocardiografia , Estudos de Viabilidade , Feminino , Peso Fetal , Transfusão Feto-Fetal/diagnóstico por imagem , Transfusão Feto-Fetal/terapia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Terapia a Laser , Gravidez , Estudos Prospectivos , Medição de Risco , Adulto Jovem
6.
J Org Chem ; 77(10): 4732-9, 2012 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-22524537

RESUMO

(S)-3-(methylamino)-3-((R)-pyrrolidin-3-yl)propanenitrile (1) is a key intermediate in the preparation of PF-00951966, (1) a fluoroquinolone antibiotic for use against key pathogens causing community-acquired respiratory tract infections including multidrug resistant (MDR) organisms. The current work describes the development of a highly efficient and stereoselective synthesis of 1 in 10 steps with an overall yield of 24% from readily available benzyloxyacetyl chloride. Two key transformations in the synthetic sequence involve (a) catalytic asymmetric hydrogenation with chiral DM-SEGPHOS-Ru(II) complex to afford ß-hydroxy amide 11b in good yield (73%) and high stereoselectivity (de 98%, ee >99%) after recrystallization and (b) S(N)2 substitution reaction with methylamine to provide diamine 14 with inversion of configuration at the 1'-position in high yield (80%), after efficient purification using a simple acid/base extraction protocol.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Fluoroquinolonas/química , Fluoroquinolonas/farmacologia , Nitrilas/química , Nitrilas/síntese química , Pirrolidinas/química , Pirrolidinas/síntese química , Catálise , Estrutura Molecular , Estereoisomerismo
7.
Bioorg Med Chem Lett ; 22(7): 2536-43, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22401863

RESUMO

Lipid A is an essential component of the Gram negative outer membrane, which protects the bacterium from attack of many antibiotics. The Lipid A biosynthesis pathway is essential for Gram negative bacterial growth and is unique to these bacteria. The first committed step in Lipid A biosynthesis is catalysis by LpxC, a zinc dependent deacetylase. We show the design of an LpxC inhibitor utilizing a robust model which directed efficient design of picomolar inhibitors. Analysis of physiochemical properties drove design to focus on an optimal lipophilicity profile. Further structure based design took advantage of a conserved water network over the active site, and with the optimal lipophilicity profile, led to an improved LpxC inhibitor with in vivo activity against wild type Pseudomonas aeruginosa.


Assuntos
Amidoidrolases/química , Antibacterianos/síntese química , Inibidores Enzimáticos/síntese química , Ácidos Hidroxâmicos/síntese química , Pseudomonas aeruginosa/efeitos dos fármacos , Amidoidrolases/antagonistas & inibidores , Antibacterianos/farmacologia , Domínio Catalítico , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Ácidos Hidroxâmicos/farmacologia , Lipídeo A/metabolismo , Testes de Sensibilidade Microbiana , Modelos Moleculares , Ligação Proteica , Pseudomonas aeruginosa/enzimologia , Relação Estrutura-Atividade , Água/química
8.
J Cardiovasc Nurs ; 27(6): 485-94, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21743339

RESUMO

BACKGROUND: Health literacy (HL) is an established independent predictor of cardiovascular outcomes. Approximately 90 million Americans have limited HL and read at the fifth grade level or lower. Therefore, we sought to determine the suitability and readability level of common cardiovascular patient education materials (PEM) related to heart failure and heart-healthy lifestyle. METHODS AND RESULTS: The suitability and readability of written PEMs were assessed using the suitability assessment of materials (SAM) and Fry readability formula. The SAM criteria are composed of the following categories: message content, text appearance, visuals, and layout and design. We obtained a convenience sample of 18 English-written cardiovascular PEMs freely available from major health organizations. Two reviewers independently appraised the PEMs. Final suitability scores ranged from 12% to 87%. Readability levels ranged between 3rd and 15th grade level; the average readability level was 8th grade. Ninety-four percent of the PEMs were rated either superior or adequate on text appearance, but 50% or more of the PEMs were rated inadequate on each of the other categories of the SAM criteria. Only 2 (11%) PEMs had the optimum suitability score of 70% or higher and 5th grade or lower readability level suitable for populations with limited HL. CONCLUSIONS: Commonly available cardiovascular PEMs used by some major healthcare institutions are not suitable for the average American patient. The true prevalence of suboptimal PEMs needs to be determined because it potentially negatively impacts optimal healthcare delivery and outcomes.


Assuntos
Doenças Cardiovasculares , Compreensão , Educação de Pacientes como Assunto/métodos , Letramento em Saúde , Insuficiência Cardíaca , Humanos , Inquéritos e Questionários
9.
Bioorg Med Chem Lett ; 20(23): 6895-8, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21035331

RESUMO

PI3 Kinases are a family of lipid kinases mediating numerous cell processes such as proliferation, migration, and differentiation. The PI3 kinase pathway is often de-regulated in cancer through PI3Kα overexpression, gene amplification, mutations, and PTEN phosphatase deletion. PI3K inhibitors represent therefore an attractive therapeutic modality for cancer treatment. Herein we describe a novel series of PI3K inhibitors sharing a pyrimidine core and showing significant potency against class I PI3 kinases in the biochemical assay and in cells. The discovery, synthesis and SAR of this chemotype are described.


Assuntos
Antineoplásicos/síntese química , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Morfolinas/química , Morfolinas/farmacologia , Fosforilação/efeitos dos fármacos , Pirimidinas/química , Relação Estrutura-Atividade
11.
J Med Chem ; 52(2): 278-92, 2009 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-19113866

RESUMO

The inhibition of key receptor tyrosine kinases (RTKs) that are implicated in tumor vasculature formation and maintenance, as well as tumor progression and metastasis, has been a major focus in oncology research over the last several years. Many potent small molecule inhibitors of vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR) kinases have been evaluated. More recently, compounds that act through the complex inhibition of multiple kinase targets have been reported and may exhibit improved clinical efficacy. We report herein a series of potent, orally efficacious 4-amino-3-benzimidazol-2-ylhydroquinolin-2-one analogues as inhibitors of VEGF, PDGF, and fibroblast growth factor (FGF) receptor tyrosine kinases. Compounds in this class, such as 5 (TKI258), are reversible ATP-competitive inhibitors of VEGFR-2, FGFR-1, and PDGFRbeta with IC(50) values <0.1 microM. On the basis of its favorable in vitro and in vivo properties, compound 5 was selected for clinical evaluation and is currently in phase I clinical trials.


Assuntos
Desenho de Fármacos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinolonas/química , Quinolonas/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Animais , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Moleculares , Inibidores de Proteínas Quinases/farmacocinética , Quinolonas/farmacocinética , Relação Estrutura-Atividade
12.
Bioorg Med Chem Lett ; 17(8): 2150-5, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17303420

RESUMO

Several novel series of nitrile-containing fluoroquinolones with weakly basic amines are reported which have reduced potential for hERG (human ether-a-go-go gene) channel inhibition as measured by the dofetilide assay. The new fluoroquinolones are potent against both Gram-positive and fastidious Gram-negative strains, including Methicillin resistant Staphylococcus aureus and fluoroquinolone-resistant Streptococcus pneumoniae. Several analogs also showed low potential for human genotoxicity as measured by the clonogenicity test. Compounds 22 and 37 (designated PF-00951966 and PF-02298732, respectively), which had good in vitro activity and in vitro safety profiles, also showed good pharmacokinetic properties in rats.


Assuntos
Antibacterianos/síntese química , Fluoroquinolonas/síntese química , Nitrilas/farmacologia , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Estrutura Molecular , Testes de Mutagenicidade , Nitrilas/química , Ratos , Relação Estrutura-Atividade
14.
Exp Brain Res ; 172(1): 94-102, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16369787

RESUMO

The brain keeps track of the changing positions of body parts in space using a spatial body schema. When subjects localise a tactile stimulus on the skin, they might either use a somatotopic body map, or use a body schema to identify the location of the stimulation in external space. Healthy subjects were touched on the fingertips, with the hands in one of two postures: either the right hand was vertically above the left, or the fingers of both hands were interwoven. Subjects made speeded verbal responses to identify either the finger or the hand that was touched. Interweaving the fingers significantly impaired hand identification across several experiments, but had no effect on finger identification. Our results suggest that identification of fingers occurs in a somatotopic representation or finger schema. Identification of hands uses a general body schema, and is influenced by external spatial location. This dissociation implies that touches on the finger can only be identified with a particular hand after a process of assigning fingers to hands. This assignment is based on external spatial location. Our results suggest a role of the body schema in the identification of structural body parts from touch.


Assuntos
Encéfalo/fisiologia , Dedos/inervação , Mãos/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Adulto , Análise de Variância , Discriminação Psicológica/fisiologia , Dedos/fisiologia , Humanos , Pessoa de Meia-Idade , Postura/fisiologia , Tempo de Reação/fisiologia , Tato/fisiologia
15.
Perception ; 33(3): 307-14, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15176615

RESUMO

Recent work on tactile perception has revealed enhanced tactile acuity and speeded spatial-choice reaction times (RTs) when viewing the stimulated body site as opposed to viewing a neutral object. Here we examine whether this body-view enhancement effect extends to visual targets. Participants performed a speeded spatial discrimination between two lights attached either to their own left index finger or to a wooden finger-shaped object, making a simple distal--proximal decision. We filmed either the finger-mounted or the object-mounted lights in separate experimental blocks and the live scene was projected onto a screen in front of the participants. Thus, participants responded to identical visual targets varying only in their context: on the body or not. Results revealed a large performance advantage for the finger-mounted stimuli: reaction times were substantially reduced, while discrimination accuracy was unaffected. With this finding we address concerns associated with previous work on the processing of stimuli attributed to the self and extend the finding of a performance advantage for such stimuli to vision.


Assuntos
Imagem Corporal , Discriminação Psicológica/fisiologia , Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Dedos , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Autoimagem
16.
Nat Neurosci ; 7(3): 219-20, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14966526

RESUMO

The perceived size of objects touching different regions of skin varies across the body surface by much less than is predicted from variations in tactile receptor density. Here we show that altering the visual experience of the body alters perceived tactile distances. We propose that the brain attempts to preserve tactile size constancy by rescaling the primary, distorted body-surface representation into object-centered space according to visual experience of the body.


Assuntos
Imagem Corporal , Encéfalo/fisiologia , Mecanorreceptores/fisiologia , Percepção Espacial/fisiologia , Tato/fisiologia , Adulto , Braço/inervação , Braço/fisiologia , Feminino , Humanos , Ilusões/fisiologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Pele/inervação
17.
Neurosci Lett ; 354(1): 22-5, 2004 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-14698473

RESUMO

We report two experiments in which non-informative vision of the finger enhanced tactile acuity on the fingertip. The right index finger was passively lifted to contact a grating. Twelve participants judged orientations of tactile gratings while viewing either the fingertip, or a neutral object presented via a mirror at the fingertip's location. In Expt. 1, tactile orientation discrimination for near-threshold gratings was improved when viewing the fingertip, compared to viewing the neutral object. Experiment 2 examined the temporal persistence of this effect, and found significant visual-tactile enhancement when a dark interval of up to 10 s intervened between viewing the finger and tactile stimulation. These results suggest that viewing the body modulates the neural circuitry of primary somatosensory cortex, outlasting visual inputs.


Assuntos
Desempenho Psicomotor/fisiologia , Córtex Somatossensorial/fisiologia , Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Dedos/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Limiar Sensorial/fisiologia
18.
Exp Brain Res ; 154(2): 238-45, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14504860

RESUMO

Perception of our own bodies is based on integration of visual and tactile inputs, notably by neurons in the brain's parietal lobes. Here we report a behavioural consequence of this integration process. Simply viewing the arm can speed up reactions to an invisible tactile stimulus on the arm. We observed this visual enhancement effect only when a tactile task required spatial computation within a topographic map of the body surface and the judgements made were close to the limits of performance. This effect of viewing the body surface was absent or reversed in tasks that either did not require a spatial computation or in which judgements were well above performance limits. We consider possible mechanisms by which vision may influence tactile processing.


Assuntos
Imagem Corporal , Orientação/fisiologia , Lobo Parietal/fisiologia , Percepção Espacial/fisiologia , Tato/fisiologia , Adulto , Sinais (Psicologia) , Retroalimentação/fisiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Física , Tempo de Reação/fisiologia , Córtex Somatossensorial/fisiologia , Vias Visuais/fisiologia
19.
Neuroreport ; 14(7): 1081-5, 2003 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-12802207

RESUMO

An abnormal sense of agency is among the most characteristic yet perplexing positive symptoms of schizophrenia. Schizophrenics may either attribute the consequences of their own actions to the intentions of others (delusions of influence), or may perceive themselves as causing events which they do not in fact control (megalomania). Previous reports have often described inaccurate agency judgements in schizophrenia, but have not identified the disordered neural mechanisms or psychological processes underlying these judgements. We report the perceived time of a voluntary action and its consequence in eight schizophrenic patients and matched controls. The patients showed an unusually strong binding effect between actions and consequences. Specifically, the temporal interval between action and consequence appeared shorter for patients than for controls. Patients may overassociate their actions with subsequent events, experiencing their actions as having unusual causal efficacy. Disorders of agency may reflect an underlying abnormality in the experience of voluntary action.


Assuntos
Conscientização/fisiologia , Percepção/fisiologia , Desempenho Psicomotor/fisiologia , Esquizofrenia/fisiopatologia , Estimulação Acústica/métodos , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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