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1.
NPJ Precis Oncol ; 6(1): 13, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35233056

RESUMO

The NCI-MATCH was designed to characterize the efficacy of targeted therapies in histology-agnostic driver mutation-positive malignancies. Sub-protocols F and G were developed to evaluate the role of crizotinib in rare tumors that harbored either ALK or ROS1 rearrangements. Patients with malignancies that progressed following at least one prior systemic therapy were accrued to the NCI-MATCH for molecular profiling, and those with actionable ALK or ROS1 rearrangements were offered participation in sub-protocols F or G, respectively. There were five patients who enrolled on Arm F (ALK) and four patients on Arm G (ROS1). Few grade 3 or 4 toxicities were noted, including liver test abnormalities, and acute kidney injury. For sub-protocol F (ALK), the response rate was 50% (90% CI 9.8-90.2%) with one complete response among the 4 eligible patients. The median PFS was 3.8 months, and median OS was 4.3 months. For sub-protocol G (ROS1) the response rate was 25% (90% CI 1.3-75.1%). The median PFS was 4.3 months, and median OS 6.2 months. Data from 3 commercial vendors showed that the prevalence of ALK and ROS1 rearrangements in histologies other than non-small cell lung cancer and lymphoma was rare (0.1% and 0.4% respectively). We observed responses to crizotinib which met the primary endpoint for ALK fusions, albeit in a small number of patients. Despite the limited accrual, some of the patients with these oncogenic fusions can respond to crizotinib which may have a therapeutic role in this setting.

3.
BJOG ; 128(11): 1752-1761, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34138505

RESUMO

OBJECTIVE: To explore the experiences of women in Scotland who accessed medical abortion at home up to 12 weeks' gestation, delivered via a telemedicine abortion service implemented in response to the coronavirus (COVID-19) pandemic, to identify areas for improvement and inform service provision. DESIGN: Qualitative interview study. SETTING: Abortion service in one National Health Service health board in Scotland. POPULATION OR SAMPLE: Twenty women who accessed telemedicine abortion services and self-administered mifepristone and misoprostol at home up to 12 weeks' gestation. METHODS: Thematic analysis of semi-structured qualitative interviews, informed by the Framework analytic approach. MAIN OUTCOME MEASURES: Women's experiences of accessing telemedicine for medical abortion at home, specifically: acceptability of the telephone consultation and remote support; views on no pre-abortion ultrasound scan; and self-administration of abortion medications at home. RESULTS: Novel study findings were three-fold: (1) participants valued the option of accessing abortion care via telemedicine and emphasised the benefits of providing a choice of telephone and in-person consultation to suit those with different life circumstances; (2) the quality of abortion care was enhanced by the telemedicine service in relation to access, comfort and flexibility, and ongoing telephone support; (3) participants described being comfortable with, and in some cases a preference for, not having an ultrasound scan. CONCLUSIONS: This research demonstrates support for the continuation of telemedicine abortion services beyond the temporary arrangements in place during COVID-19, and lends weight to the argument that offering the option of telemedicine abortion care can enable women to access this essential health service. TWEETABLE ABSTRACT: #Telemedicine provision of medical #abortion at home up to 12 weeks' gestation is acceptable and highly valued by #women #Research #SRHR @nbw80 @doctorjjrw @jeniharden @cameronsharon @mrc_crh @edinuniusher.


Assuntos
Abortivos não Esteroides/administração & dosagem , Aborto Induzido/métodos , Satisfação do Paciente , Autoadministração/psicologia , Telemedicina/métodos , Aborto Induzido/psicologia , Adulto , COVID-19 , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Mifepristona/administração & dosagem , Misoprostol/administração & dosagem , Gravidez , Pesquisa Qualitativa , SARS-CoV-2 , Escócia , Medicina Estatal
4.
Phys Life Rev ; 36: 83-99, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32527680

RESUMO

The assumption that during cortical embryogenesis neurons and synaptic connections are selected to form an ensemble maximising synchronous oscillation explains mesoscopic cortical development, and a mechanism for cortical information processing is implied by consistency with the Free Energy Principle and Dynamic Logic. A heteroclinic network emerges, with stable and unstable fixed points of oscillation corresponding to activity in symmetrically connected, versus asymmetrically connected, sets of neurons. Simulations of growth explain a wide range of anatomical observations for columnar and non-columnar cortex, superficial patch connections, and the organization and dynamic interactions of neurone response properties. An antenatal scaffold is created, upon which postnatal learning can establish continuously ordered neuronal representations, permitting matching of co-synchronous fields in multiple cortical areas to solve optimization problems as in Dynamic Logic. Fast synaptic competition partitions equilibria, minimizing "the curse of dimensionality", while perturbations between imperfectly partitioned synchronous fields, under internal reinforcement, enable the cortex to become adaptively self-directed. As learning progresses variational free energy is minimized and entropy bounded.


Assuntos
Fenômenos Biológicos , Cognição , Desenvolvimento Embrionário , Entropia , Feminino , Humanos , Aprendizagem , Gravidez
5.
J Neurooncol ; 136(1): 79-86, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28988377

RESUMO

Recurrent glioblastoma (GBM) has a very low 6-month progression free survival (PFS) with currently available treatments. Combination chemotherapy to target multiple cell signaling pathways is currently being investigated in order to improve prognosis for recurrent disease. The purpose of this phase I study was to determine the maximum tolerated dose (MTD) for the combination of tipifarnib and sorafenib for the treatment of recurrent GBM. Patients with pathologically proven WHO grade IV GBM and radiographically proven tumor recurrence were eligible for this study. Treatments included sorafenib at twice daily and escalating dosages of tipifarnib. Dose-limiting toxicity (DLT) was determined over the first 28-days of treatments, and the MTD was determined in a 3 + 3 study design. We enrolled 24 patients, and 21 patients completed the MTD period. The study was stopped early with no MTD determination for excessive toxicities. The last dose level reached was sorafenib at 200 mg twice a day and tipifarnib 100 mg twice a day on an alternating week schedule. The DLTs included diarrhea, lipase elevation, hypophosphatemia, and arthralgia. The combination of sorafenib and tipifarnib has excessive toxicities and full single agent dosages could not be achieved in combination.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Quinolonas/uso terapêutico , Sorafenibe/uso terapêutico , Adulto , Idoso , Antineoplásicos/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Quinolonas/farmacocinética , Sorafenibe/farmacocinética , Resultado do Tratamento
6.
J Fish Biol ; 91(3): 789-805, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28744868

RESUMO

The examination of material representing one of Lake Tanganyika's six previously recognized endemic catfish lineages, has revealed the presence of an additional genus of clariid, described here as Pseudotanganikallabes new genus. This genus is represented by a single species, Pseudotanganikallabes prognatha sp. nov., which is distinguished from all other clariids by its lack of an infraorbital series, the presence of multiple osseous connections between the swim bladder capsules and elements of the neurocranium, the absence of an ethmoid notch, the presence of a very large, egg-shaped occipital fontanelle and the extension of the lower lip beyond the margin of the upper jaw. A combination of additional external and molecular characters serves to further distinguish this taxon from all currently recognized clariid species. Phylogenetic analysis of mitochondrial (cytb) and nuclear (18S-ITS1-5.8S-ITS2-28S) sequence data supports the creation of a new genus for this species, as it appears to represent an independent, monophyletic lineage within the family Clariidae.


Assuntos
Peixes-Gato/classificação , Filogenia , Animais , Peixes-Gato/anatomia & histologia , Peixes-Gato/genética , DNA Mitocondrial/química , Lagos , Especificidade da Espécie , Tanzânia
7.
Clin Pharmacol Ther ; 96(1): 27-35, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24637941

RESUMO

Hypertension after treatment with vascular endothelial growth factor (VEGF) receptor inhibitors is associated with superior treatment outcomes for advanced cancer patients. To determine whether increased sorafenib doses cause incremental increases in blood pressure (BP), we measured 12-h ambulatory BP in 41 normotensive advanced solid tumor patients in a randomized dose-escalation study. After 7 days' treatment (400 mg b.i.d.), mean diastolic BP (DBP) increased in both study groups. After dose escalation, group A (400 mg t.i.d.) had marginally significant further increase in 12-h mean DBP (P = 0.053), but group B (600 mg b.i.d.) did not achieve statistically significant increases (P = 0.25). Within groups, individuals varied in BP response to sorafenib dose escalation, but these differences did not correlate with changes in steady-state plasma sorafenib concentrations. These findings in normotensive patients suggest BP is a complex pharmacodynamic biomarker of VEGF inhibition. Patients have intrinsic differences in sensitivity to sorafenib's BP-elevating effects.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Adulto , Idoso , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias/patologia , Neoplasias/fisiopatologia , Niacinamida/administração & dosagem , Niacinamida/farmacocinética , Compostos de Fenilureia/farmacocinética , Estudos Prospectivos , Sorafenibe , Adulto Jovem
8.
Bioorg Med Chem Lett ; 23(5): 1228-31, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23374868

RESUMO

A novel series of CCR1 antagonists based on the 1-(4-phenylpiperazin-1-yl)-2-(1H-pyrazol-1-yl)ethanone scaffold was identified by screening a compound library utilizing CCR1-expressing human THP-1 cells. SAR studies led to the discovery of the highly potent and selective CCR1 antagonist 14 (CCR1 binding IC(50)=4 nM using [(125)I]-CCL3 as the chemokine ligand). Compound 14 displayed promising pharmacokinetic and toxicological profiles in preclinical species.


Assuntos
Piperazinas/farmacologia , Pirazóis/farmacologia , Receptores CCR1/antagonistas & inibidores , Linhagem Celular , Humanos , Piperazinas/química , Pirazóis/química , Receptores CCR1/metabolismo , Relação Estrutura-Atividade
10.
Invest New Drugs ; 30(3): 1175-83, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21424698

RESUMO

PURPOSE: Patients with metastatic pancreatic cancer have limited therapeutic options. The role of the Ras-Raf-MAPK pathway and of vascular endothelial growth factor in pancreatic carcinogenesis provided the rational to evaluate the efficacy of sorafenib with or without gemcitabine in a randomized phase II study. METHODS: Patients with metastatic pancreatic cancer were randomized to sorafenib alone (arm A) or sorafenib with gemcitabine (arm B). RESULTS: Arm A was closed to accrual at interim analysis due to the lack of objective response. Median PFS and OS were 2.3 and 4.3 months respectively. There was one partial response among the 37 patients in arm B. Median PFS and OS were 2.9 and 6.5 months respectively. There were more grade 3 and 4 toxicities in arm B with the most common being neutropenia (17%), thrombocytopenia (8%), alkaline phosphatase elevation (14%), venous thromboembolism (8%), diarrhea, hypokalemia and ALT elevation (5%) each. Several associations were noted between single nucleotide polymorphisms in ribonucleotide reductase, Cox-2, vascular endothelial growth factor and survival in patients treated with gemcitabine and sorafenib. CONCLUSIONS: Neither sorafenib alone or sorafenib in combination with gemcitabine manifested promising activity in metastatic pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclo-Oxigenase 2/genética , Nucleosídeo Desaminases/genética , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzenossulfonatos/administração & dosagem , Benzenossulfonatos/efeitos adversos , Citidina Desaminase , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Niacinamida/análogos & derivados , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Compostos de Fenilureia , Polimorfismo de Nucleotídeo Único , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Ribonucleosídeo Difosfato Redutase , Sorafenibe , Gencitabina
11.
Bull Math Biol ; 73(2): 436-57, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20821066

RESUMO

Ongoing changes in attention and cognition depend upon cortical/subcortical interactions, which select sequences of different spatial patterns of activation in the cortex. It is proposed that each pattern of cortical activation permits evolution of electrocortical wave activity toward statistically stationary states, analogous to thermodynamic equilibrium. In each steady-state, neurons fire with an intrinsic Poisson spike probability and also with a bursting pattern related to network oscillations. Excitatory cell dendrites act as a regenerative reservoir in which pulse generation is balanced against dissipations. Equilibria exhibit contrasting limits. One limit, at high cortical activation, generates widespread zero-lag synchrony among excitatory cells, with partial suppression of noise. Excitatory and inhibitory cells approach zero-lag local correlation, with 1/4 cycle lag-correlation at greater distances of separation. The high-activation limit defines a correlated system of attractor basins, capable of co-ordinating synaptic modifications and intracortical signal generation. Suppression of noise would enhance convergence about attractor basins in the manner of simulated annealing, while, conversely, the persistence of some noise prevents network paralysis by phase locking. At the opposite limit-that of low activation-spikes and waves have low cross- and auto-correlation, but have wide-spectrum sensitivity to inputs. It is hypothesised that cortical regions, transiently at equilibrium near these extremes, engage in interaction with each other and with subcortical systems, to generate ongoing sequences of attention and cognition. This account is compatible with classical and recently observed experimental phenomena. The principle features inferred from a simplified linear mathematical account are reproduced in a more physiologically realistic and non-linear numerical simulation.


Assuntos
Potenciais de Ação/fisiologia , Atenção/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia , Modelos Neurológicos , Termodinâmica , Algoritmos , Cognição/fisiologia , Simulação por Computador , Dendritos/fisiologia , Entropia , Humanos , Potenciais da Membrana/fisiologia , Rede Nervosa/fisiologia , Inibição Neural/fisiologia , Processos Estocásticos , Transmissão Sináptica/fisiologia
12.
J Pharmacol Exp Ther ; 335(1): 61-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20660125

RESUMO

The chemokine system represents a diverse group of G protein-coupled receptors responsible for orchestrating cell recruitment under both homeostatic and inflammatory conditions. Chemokine receptor 9 (CCR9) is a chemokine receptor known to be central for migration of immune cells into the intestine. Its only ligand, CCL25, is expressed at the mucosal surface of the intestine and is known to be elevated in intestinal inflammation. To date, there are no reports of small-molecule antagonists targeting CCR9. We report, for the first time, the discovery of a small molecule, CCX282-B, which is an orally bioavailable, selective, and potent antagonist of human CCR9. CCX282-B inhibited CCR9-mediated Ca(2+) mobilization and chemotaxis on Molt-4 cells with IC(50) values of 5.4 and 3.4 nM, respectively. In the presence of 100% human serum, CCX282-B inhibited CCR9-mediated chemotaxis with an IC(50) of 33 nM, and the addition of α1-acid glycoprotein did not affect its potency. CCX282-B inhibited chemotaxis of primary CCR9-expressing cells to CCL25 with an IC(50) of 6.8 nM. CCX282-B was an equipotent inhibitor of CCL25-directed chemotaxis of both splice forms of CCR9 (CCR9A and CCR9B) with IC(50) values of 2.8 and 2.6 nM, respectively. CCX282-B also inhibited mouse and rat CCR9-mediated chemotaxis. Inhibition of CCR9 with CCX282-B results in normalization of Crohn's disease such as histopathology associated with the TNF(ΔARE) mice. Analysis of the plasma level of drug associated with this improvement provides an understanding of the pharmacokinetic/pharmacodynamic relationship for CCR9 antagonists in the treatment of intestinal inflammation.


Assuntos
Fármacos Gastrointestinais/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Receptores CCR/antagonistas & inibidores , Sulfonamidas/farmacologia , Administração Oral , Animais , Cálcio/metabolismo , Linhagem Celular , Quimiotaxia de Leucócito/efeitos dos fármacos , Doença de Crohn/tratamento farmacológico , Doença de Crohn/patologia , Fármacos Gastrointestinais/farmacocinética , Humanos , Ileíte/induzido quimicamente , Ileíte/tratamento farmacológico , Ileíte/patologia , Camundongos , Camundongos Endogâmicos C57BL , Ensaio Radioligante , Ratos , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Tretinoína/farmacologia , Fator de Necrose Tumoral alfa/fisiologia
13.
Leukemia ; 24(8): 1437-44, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20535150

RESUMO

We report the results of a phase I dose escalation trial of the multikinase inhibitor sorafenib in relapsed and refractory acute leukemia patients using an intermittent dosing regimen. Fifteen patients with advanced leukemia (12 with acute myeloid leukemia, 2 with acute lymphoblastic leukemia, 1 with biphenotypic) and a median age of 63 (range 37-85) years were enrolled and treated on a dose escalation trial. Toxicities >or=grade 3 were present in 55% of cycles and the maximum tolerated dose (MTD) was determined to be 400 mg b.i.d. x 21 days in a 28-day cycle. Plasma inhibitory assays of kinase targets extracellular signal-regulated kinase (ERK) and FLT3-internal tandem duplication (ITD) showed excellent target inhibition, with FLT3-ITD silencing occurring below the MTD. The N-oxide metabolite of sorafenib seemed to be a more potent inhibitor of FLT3-ITD than the parent compound. Despite marked ex vivo FLT-3 ITD inhibition, no patients met the criteria for complete or partial response in this monotherapy study. Out of 15 patients, 11 experienced stable disease as best response. Although sorafenib showed only modest clinical activity as a single agent in this heavily treated population, robust inhibition of FLT3 and ERK suggests that there may be a potential important role in combination therapies.


Assuntos
Antineoplásicos/uso terapêutico , Benzenossulfonatos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Benzenossulfonatos/farmacocinética , Benzenossulfonatos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Feminino , Humanos , Leucemia Mieloide Aguda/sangue , Masculino , Pessoa de Meia-Idade , Niacinamida/análogos & derivados , Compostos de Fenilureia , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacocinética , Piridinas/farmacologia , Recidiva , Sorafenibe , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores
14.
Bioorg Med Chem Lett ; 19(17): 5136-9, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19632112

RESUMO

1-(4-Benzoylpiperazin-1-yl)-2-(1H-indol-3-yl)ethane-1,2-dione (1a) has been characterized as an inhibitor of HIV-1 attachment that interferes with the interaction of viral gp120 with the host cell receptor CD4. In previous studies, the effect of indole substitution pattern on antiviral activity was probed. In this Letter, the effect of structural variation of the benzamide moiety is described, a study that reveals the potential or the phenyl moiety to be replaced by five-membered heterocyclic rings and a restricted tolerance for the introduction of substituents to the phenyl ring.


Assuntos
Fármacos Anti-HIV/química , Benzamidas/química , Proteína gp120 do Envelope de HIV/antagonistas & inibidores , Inibidores da Fusão de HIV/química , Indóis/química , Piperazinas/química , Ligação Viral/efeitos dos fármacos , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Benzamidas/síntese química , Benzamidas/farmacologia , Linhagem Celular , Proteína gp120 do Envelope de HIV/metabolismo , Inibidores da Fusão de HIV/síntese química , Inibidores da Fusão de HIV/farmacologia , Humanos , Indóis/síntese química , Indóis/farmacologia , Piperazinas/síntese química , Piperazinas/farmacologia , Relação Estrutura-Atividade
15.
Bioorg Med Chem Lett ; 19(7): 1977-81, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19251416

RESUMO

The effects of introducing simple halogen, alkyl, and alkoxy substituents to the 4, 5, 6 and 7 positions of 1-(4-benzoylpiperazin-1-yl)-2-(1H-indol-3-yl)ethane-1,2-dione, an inhibitor of the interaction between HIV gp120 and host cell CD4 receptors, on activity in an HIV entry assay was examined. Small substituents at C-4 generally resulted in increased potency whilst substitution at C-7 was readily tolerated and uniformly produced more potent HIV entry inhibitors. Substituents deployed at C-6 and, particularly, C-5 generally produced a modest to marked weakening of potency compared to the prototype. Small alkyl substituents at N-1 exerted minimal effect on activity whilst increasing the size of the alkyl moiety led to progressively reduced inhibitory properties. These studies establish a basic understanding of the indole element of the HIV attachment inhibitor pharmacophore.


Assuntos
Inibidores da Fusão de HIV/química , Inibidores da Fusão de HIV/farmacologia , HIV-1/efeitos dos fármacos , Indóis/farmacologia , Ligação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Cães , Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/prevenção & controle , Humanos , Indóis/química , Indóis/farmacocinética , Ratos , Relação Estrutura-Atividade
16.
Ann Oncol ; 20(4): 642-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19153124

RESUMO

BACKGROUND: Fulvestrant produces a clinical benefit rate (CBR) of approximately 45% in tamoxifen-resistant, hormone receptor (HR)-positive metastatic breast cancer (MBC) and 32% in aromatase inhibitor (AI)-resistant disease. The farnesyltransferase inhibitor tipifarnib inhibits Ras signaling and has preclinical and clinical activity in endocrine therapy-resistant disease. The objective of this study was to determine the efficacy and safety of tipifarnib-fulvestrant combination in HR-positive MBC. PATIENTS AND METHODS: Postmenopausal women with no prior chemotherapy for metastatic disease received i.m. fulvestrant 250 mg on day 1 plus oral tipifarnib 300 mg twice daily on days 1-21 every 28 days. The primary end point was CBR. RESULTS: The CBR was 51.6% [95% confidence interval (CI) 34.0% to 69.2%] in 31 eligible patients and 47.6% (95% CI 26.3% to 69.0%) in 21 patients with AI-resistant disease. A futility analysis indicated that it was unlikely to achieve the prespecified 70% CBR. Tipifarnib dose modification was required in 8 of 33 treated patients (24%). CONCLUSIONS: The target CBR of 70% for the tipifarnib-fulvestrant combination in HR-positive MBC was set too high and was not achieved. The 48% CBR in AI-resistant disease compares favorably with the 32% CBR observed with fulvestrant alone in prior studies and merit further clinical and translational evaluation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Estradiol/análogos & derivados , Farnesiltranstransferase/antagonistas & inibidores , Quinolonas/uso terapêutico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/metabolismo , Estradiol/administração & dosagem , Estradiol/efeitos adversos , Estradiol/uso terapêutico , Feminino , Fulvestranto , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Quinolonas/administração & dosagem , Quinolonas/efeitos adversos , Resultado do Tratamento
17.
Neural Netw ; 22(4): 373-84, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19095406

RESUMO

A continuum model of electrocortical activity was applied separately at centimetric and macrocolumnar scales, permitting analysis of interaction between scales. State equations included effects of retrograde action potential propagation in dendritic trees, and kinetics of AMPA, GABA and NMDA receptors. Parameter values were provided from independent physiological and anatomical estimates. Realistic field potentials and pulse rates were obtained, including resonances in the alpha/theta and gamma ranges, 1/f(2) background activity, and autonomous gamma activity. Zero-lag synchrony and travelling waves occurred as complementary aspects of cortical transmission, and lead/lag relations between excitatory and inhibitory cell populations varied systematically around transition to autonomous gamma oscillation. Properties of the simulations can account for generation and control of gamma activity. All factors acting on excitatory/inhibitory balance controlled the onset and offset of gamma oscillation. Autonomous gamma was initiated by focal excitation of excitatory cells, and suppressed by laterally spreading trans-cortical excitation, which acted on both excitatory and inhibitory cell populations. Consequently, although spatially extensive non-specific reticular activation tended to suppress autonomous gamma, spatial variation of reticular activation could preferentially select fields of synchrony.


Assuntos
Relógios Biológicos/fisiologia , Córtex Cerebral/fisiologia , Sincronização Cortical , Potenciais Evocados/fisiologia , Rede Nervosa/fisiologia , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Algoritmos , Animais , Simulação por Computador , Eletroencefalografia , Humanos , Inibição Neural/fisiologia , Redes Neurais de Computação , Vias Neurais/fisiologia , Formação Reticular/fisiologia , Transmissão Sináptica/fisiologia , Vigília/fisiologia
18.
Cogn Neurodyn ; 2(2): 147-57, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19003481

RESUMO

A model of self-organization of synapses in the striate cortex is described, and its functional implications discussed. Principal assumptions are: (a) covariance of cell firing declines with distance in cortex, (b) covariance of stimulus characteristics declines with distance in the visual field, and (c) metabolic rates are approximately uniform in all small axonal segments. Under these constraints, Hebbian learning implies a maximally stable synaptic configuration corresponding to anatomically and physiologically realistic ''local maps'', each of macro-columnar size, and each organized as Möbius projections of a "global map" of retinotopic form. Convergence to the maximally stable configuration is facilitated by the spatio-temporal learning rule. A tiling of V1, constructed of approximately mirror-image reflections of each local map by its neighbors, is formed. The model supplements standard concepts of feed-forward visual processing by introducing a new basis for contextual modulation and neural network identifications of visual signals, as perturbation of the synaptic configuration by rapid stimulus transients. On a long time-scale, synaptic development could overwrite the Möbius configuration, while LTP and LTD could mediate synaptic gain on intermediate time-scales.

20.
Bioorg Med Chem Lett ; 17(4): 895-901, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17169560

RESUMO

A series of benzimidazole-based inhibitors of respiratory syncytial virus (RSV) fusion were optimized for antiviral potency, membrane permeability and metabolic stability in human liver microsomes. 1-Cyclopropyl-1,3-dihydro-3-[[1-(4-hydroxybutyl)-1H-benzimidazol-2-yl]methyl]-2H-imidazo[4,5-c]pyridin-2-one (6m, BMS-433771) was identified as a potent RSV inhibitor demonstrating good bioavailability in the mouse, rat, dog and cynomolgus monkey that demonstrated antiviral activity in the BALB/c and cotton rat models of infection following oral administration.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Animais , Antivirais/farmacocinética , Benzimidazóis/farmacocinética , Disponibilidade Biológica , Células CACO-2 , Fenômenos Químicos , Físico-Química , Efeito Citopatogênico Viral/efeitos dos fármacos , Cães , Meia-Vida , Humanos , Técnicas In Vitro , Macaca fascicularis , Camundongos , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/efeitos dos fármacos , Ratos , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/virologia , Sigmodontinae , Relação Estrutura-Atividade
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