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1.
Ann Oncol ; 34(5): 477-485, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36858151

RESUMO

BACKGROUND: The first interim analysis of the phase III, randomized, double-blind, placebo-controlled, multinational TITAN study demonstrated improved overall survival (OS) and radiographic progression-free survival (rPFS) with apalutamide added to ongoing androgen deprivation therapy (ADT) in patients with metastatic castration-sensitive prostate cancer. The final analysis confirmed improvement in OS and other long-term outcomes. We evaluated prostate-specific antigen (PSA) kinetics and the association between PSA decline and outcomes in patients with metastatic castration-sensitive prostate cancer from TITAN. PATIENTS AND METHODS: Patients received apalutamide (240 mg/day) or placebo plus ADT (1 : 1). This post hoc exploratory analysis evaluated PSA kinetics and decline in relation to rPFS (22.7 months' follow-up) and OS, time to PSA progression, and time to castration resistance (44.0 months' follow-up) in patients with or without confirmed PSA decline using a landmark analysis, the Kaplan-Meier method, and Cox proportional hazards model. RESULTS: One thousand and fifty-two patients (apalutamide, 525; placebo, 527) were enrolled. Best confirmed PSA declines (≥50% or ≥90% from baseline or to ≤0.2 ng/ml) were achieved at any time during the study in 90%, 73%, and 68% of apalutamide-treated versus 55%, 29%, and 32% of placebo-treated patients, respectively. By 3 months of apalutamide treatment, best deep PSA decline of ≥90% or to ≤0.2 ng/ml occurred in 59% and 51% of apalutamide- and in 13% and 18% of placebo-treated patients, respectively. Achievement of deep PSA decline at landmark 3 months of apalutamide treatment was associated with longer OS [hazard ratio (HR) 0.35; 95% confidence interval (CI) 0.25-0.48), rPFS (HR 0.44; 95% CI 0.30-0.65), time to PSA progression (HR 0.31; 95% CI 0.22-0.44), and time to castration resistance (HR 0.38; 95% CI 0.27-0.52) compared with no decline (P < 0.0001 for all). Similar results were observed at landmark 6 and 12 months of apalutamide treatment. CONCLUSIONS: Apalutamide plus ADT demonstrated a robust (rapid, deep, and durable) PSA decline that was associated with improved clinical outcomes, including long-term survival.


Assuntos
Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Antagonistas de Androgênios/uso terapêutico , Androgênios/uso terapêutico , Castração
2.
Brain Behav Immun ; 68: 183-196, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29061364

RESUMO

Microglia, like macrophages, can adopt inflammatory and anti-inflammatory phenotypes depending on the stimulus. In macrophages, the evidence indicates that these phenotypes have different metabolic profiles with lipopolysaccharide (LPS)- or interferon-γ (IFNγ)-stimulated inflammatory cells switching to glycolysis as their main source of ATP and interleukin-4 (IL-4)-stimulated cells utilizing oxidative phosphorylation. There is a paucity of information regarding the metabolic signatures of inflammatory and anti-inflammatory microglia. Here, we polarized primary microglia with IFNγ and show that the characteristic increases in tumor necrosis factor-α (TNFα) and nitric oxide synthase 2 (NOS2) were accompanied by increased glycolysis and an increase in the expression of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase (PFKFB)3, an enzyme that plays a significant role in driving glycolysis. These changes were associated with increased expression of ferritin and retention of iron in microglia. Significantly, retention of iron in microglia increased TNFα expression and also increased glycolysis suggesting that increased intracellular iron concentration may drive the metabolic and/or inflammatory changes. Analysis of microglia prepared from wildtype mice and from transgenic mice that overexpress amyloid precursor protein (APP) and presenilin 1 (PS1; APP/PS1) revealed genotype-related increases in glycolysis, accompanied by increased PFKFB3, and an increase in the expression of ferritin. The data indicate a distinct metabolic signature of inflammatory microglia from APP/PS1 mice that are also distinguishable by their iron handling profiles.


Assuntos
Microglia/imunologia , Microglia/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Ferritinas/metabolismo , Glicólise/fisiologia , Inflamação/metabolismo , Interferon gama/metabolismo , Interleucina-4/metabolismo , Ferro/metabolismo , Lipopolissacarídeos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo II/metabolismo , Fosfofrutoquinase-2/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
3.
Appl Environ Microbiol ; 82(7): 2167-2176, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26826233

RESUMO

Scombrotoxin fish poisoning (SFP) remains the main contributor of fish poisoning incidents in the United States, despite efforts to control its spread. Psychrotrophic histamine-producing bacteria (HPB) indigenous to scombrotoxin-forming fish may contribute to the incidence of SFP. We examined the gills, skin, and anal vents of yellowfin (n = 3), skipjack (n = 1), and albacore (n = 6) tuna for the presence of indigenous HPB. Thirteen HPB strains were isolated from the anal vent samples from albacore (n = 3) and yellowfin (n = 2) tuna. Four of these isolates were identified as Photobacterium kishitanii and nine isolates as Photobacterium angustum; these isolates produced 560 to 603 and 1,582 to 2,338 ppm histamine in marine broth containing 1% histidine (25°C for 48 h), respectively. The optimum growth temperatures and salt concentrations were 26 to 27°C and 1% salt for P. kishitanii and 30 to 32°C and 2% salt for P. angustum in Luria 70% seawater (LSW-70). The optimum activity of the HDC enzyme was at 15 to 30°C for both species. At 5°C, P. kishitanii and P. angustum had growth rates of 0.1 and 0.2 h(-1), respectively, and the activities of histidine decarboxylase (HDC) enzymes were 71% and 63%, respectively. These results show that indigenous HPB in tuna are capable of growing at elevated and refrigeration temperatures. These findings demonstrate the need to examine the relationships between the rate of histamine production at refrigeration temperatures, seafood shelf life, and regulatory limits.


Assuntos
Histamina/biossíntese , Photobacterium/metabolismo , Alimentos Marinhos/microbiologia , Atum/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Contaminação de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Histamina/toxicidade , Histidina Descarboxilase/genética , Histidina Descarboxilase/metabolismo , Toxinas Marinhas/metabolismo , Toxinas Marinhas/toxicidade , Photobacterium/classificação , Photobacterium/enzimologia , Photobacterium/genética , Filogenia
4.
ESMO Open ; 9(5): 103007, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38744101

RESUMO

BACKGROUND: Understanding stakeholders' perception of cure in prostate cancer (PC) is essential to preparing for effective communication about emerging treatments with curative intent. This study used artificial intelligence (AI) for landscape review and linguistic analysis of definition, context and value of cure among stakeholders in PC. MATERIALS AND METHODS: Subject-matter experts (SMEs) selected cure-related key words using Elicit, a semantic literature search engine, and extracted hits containing the key words from Medline, Sermo and Overton, representing academic researchers, health care providers (HCPs) and policymakers, respectively. NetBase Quid, a social media analytics and natural language processing tool, was used to carry out key word searches in social media (representing the general public). NetBase Quid analysed linguistics of key word-specific hit sets for key word count, geolocation and sentiments. SMEs qualitatively summarised key word-specific insights. Contextual terms frequently occurring with key words were identified and quantified. RESULTS: SMEs identified seven key words applicable to PC (number of acquired hits) across four platforms: Cure (12429), Survivor (6063), Remission (1904), Survivorship (1179), Curative intent (432), No evidence of disease (381) and Complete remission (83). Most commonly used key words were Cure by the general public and HCPs (11815 and 224 hits), Survivorship by academic researchers and Survivor by policymakers (378 hits each). All stakeholders discussed Cure and cure-related key words primarily in early-stage PC and associated them with positive sentiments. All stakeholders defined cure differently but communicated about it in relation to disease measurements (e.g. prostate-specific antigen) or surgery. Stakeholders preferred different terms when discussing cure in PC: Cure (academic researchers), Cure rates (HCPs), Potential cure and Survivor/Survivorship (policymakers) and Cure and Survivor (general public). CONCLUSION: This human-led, AI-assisted large-scale qualitative language-based research revealed that cure was commonly discussed by academic researchers, HCPs, policymakers and the general public, especially in early-stage PC. Stakeholders defined and contextualised cure in their communications differently and associated it with positive value.


Assuntos
Inteligência Artificial , Neoplasias da Próstata , Mídias Sociais , Humanos , Masculino , Neoplasias da Próstata/terapia , Linguística/métodos , Política de Saúde , Percepção , Processamento de Linguagem Natural
5.
Int J Behav Med ; 19(2): 165-73, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21562781

RESUMO

BACKGROUND: Somatisation disorder (SD) has been reported as common in all ethnic groups, but the estimates of its prevalence have varied and the evidence for its associated factors has been inconsistent. PURPOSE: This study seeks to determine the prevalence of SD and its associated factors in multiethnic primary care clinic attenders. METHODS: This cross-sectional study was on clinic attenders aged 18 years and above at three urban primary care clinics in Malaysia. The operational definition of SD was based on ICD-10 criteria for SD for research, frequent attendance, and excluded moderate to severe anxiety and depression. The instruments used were the ICD-10 symptom list, the Hospital Anxiety and Depression Scale, a semi-structured questionnaire, and SF-36. RESULTS: We recruited 1,763 patients (response rate 63.8%). The mean age of respondents was 44.7 ± 15.8 years, 807 (45.8%) were male; there were 35.3% Malay, 30.1% Chinese and 34.6% Indian. SD prevalence was 3.7%; the prevalence in Malay was 5.8%, Indian 3.0% and Chinese 2.1%. Significant associations were found between SD prevalence and ethnicity, family history of alcoholism, blue-collar workers and the physical component summary (PCS) score of SF-36. Multivariate analysis showed that SD predictors were Malay ethnicity (OR 2.7, 95% CI 1.6, 4.6), blue-collar worker (OR 2.0, 95% CI 1.2, 3.5) and impaired PCS score of SF-36 (OR 0.92, 95% CI 0.90, 0.95). CONCLUSION: The prevalence of SD was relatively uncommon with the stringent operational criteria used. SD preponderance in blue-collar workers may be attributable to secondary gain from getting sickness certificates and being paid for time off work.


Assuntos
Comparação Transcultural , Características Culturais , Transtornos Somatoformes/etnologia , Adulto , Fatores Etários , Distribuição de Qui-Quadrado , China/etnologia , Estudos Transversais , Feminino , Humanos , Índia/etnologia , Malásia/etnologia , Masculino , Pessoa de Meia-Idade , Prevalência , Atenção Primária à Saúde/estatística & dados numéricos , Fatores Sexuais , Fatores Socioeconômicos , Transtornos Somatoformes/diagnóstico , Estatísticas não Paramétricas
6.
J Exp Med ; 169(6): 2085-96, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2525172

RESUMO

We examined the possible role of CD4 molecules during in vivo and in vitro fetal thymic development. Our results show that fetal thymi treated with intact anti-CD4 mAbs fail to generate CD4 single-positive T cells, while the generation of the other phenotypes remains unchanged. Most importantly, the use of F(ab')2 and Fab anti-CD4 mAb gave identical results, i.e., failure to generate CD4+/CD8- T cells, with no effect on the generation of CD4+/CD8+ T cells. Since F(ab')2 and Fab anti-CD4 fail to deplete CD4+/CD8- in adult mice, these results strongly argue that the absence of CD4+/CD8- T cells is not due to depletion, but rather, is caused by a lack of positive selection, attributable to an obstructed CD4-MHC class II interaction. Furthermore, we also observed an increase in TCR/CD3 expression after anti-CD4 (divalent or monovalent) mAb treatment. The TCR/CD3 upregulation occurs in the double-positive population, and may result from CD4 signaling after mAb engagement, or may be a consequence of the blocked CD4-class II interactions. One proposed model argues that the CD3 upregulation occurs in an effort to compensate for the reduction in avidity or signaling that is normally provided by the interaction of the CD4 accessory molecule and its ligand. As a whole, our findings advocate that CD4 molecules play a decisive role in the differentiation of thymocytes.


Assuntos
Antígenos de Diferenciação de Linfócitos T/fisiologia , Linfócitos T/fisiologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/fisiologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Complexo CD3 , Diferenciação Celular , Feminino , Feto , Antígenos de Histocompatibilidade Classe II/imunologia , Fragmentos Fab das Imunoglobulinas/fisiologia , Imunossupressores/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Técnicas de Cultura de Órgãos , Gravidez , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/classificação , Linfócitos T/imunologia
7.
Science ; 249(4976): 1558-61, 1990 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-2120773

RESUMO

Most immature CD4+CD8+ thymocytes express only a small number of T cell receptor (TCR) molecules on their surface, and the TCR molecules they do express are only marginally capable of transducing intracellular signals. TCR expression and function was not intrinsically low in immature CD4+CD8+ thymocytes, but was found to be actively inhibited by CD4-mediated signals. Indeed, release of CD4+CD8+ thymocytes from CD4-mediated signals resulted in significant increases in both TCR expression and signaling function. These results suggest that, in CD4+CD8+ cells developing in the thymus, increased TCR expression and function requires release from CD4-mediated inhibition.


Assuntos
Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos CD4/imunologia , Receptores de Antígenos de Linfócitos T/fisiologia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antígenos CD8 , Membrana Celular/imunologia , Células Cultivadas , Antígenos de Histocompatibilidade Classe II/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T/biossíntese
8.
J Pharmacol Exp Ther ; 325(2): 681-90, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18287214

RESUMO

We have recently proposed the hypothesis that inhibition of the cyclic nucleotide phosphodiesterase (PDE) 10A may represent a new pharmacological approach to the treatment of schizophrenia (Curr Opin Invest Drug 8:54-59, 2007). PDE10A is highly expressed in the medium spiny neurons of the mammalian striatum (Brain Res 985:113-126, 2003; J Histochem Cytochem 54:1205-1213, 2006; Neuroscience 139:597-607, 2006), where the enzyme is hypothesized to regulate both cAMP and cGMP signaling cascades to impact early signal processing in the corticostriatothalamic circuit (Neuropharmacology 51:374-385, 2006; Neuropharmacology 51:386-396, 2006). Our current understanding of the physiological role of PDE10A and the therapeutic utility of PDE10A inhibitors derives in part from studies with papaverine, the only pharmacological tool for this target extensively profiled to date. However, this agent has significant limitations in this regard, namely, relatively poor potency and selectivity and a very short exposure half-life after systemic administration. In the present report, we describe the discovery of a new class of PDE10A inhibitors exemplified by TP-10 (2-{4-[-pyridin-4-yl-1-(2,2,2-trifluoro-ethyl)-1H-pyrazol-3-yl]-phenoxymethyl}-quinoline succinic acid), an agent with greatly improved potency, selectivity, and pharmaceutical properties. These new pharmacological tools enabled studies that provide further evidence that inhibition of PDE10A represents an important new target for the treatment of schizophrenia and related disorders of basal ganglia function.


Assuntos
Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/fisiologia , Pirazóis/farmacologia , Quinolinas/farmacologia , Esquizofrenia/tratamento farmacológico , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Dopamina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Inibidores de Fosfodiesterase/sangue , Inibidores de Fosfodiesterase/farmacocinética , Diester Fosfórico Hidrolases/genética , Ratos , Ratos Endogâmicos F344 , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/genética , Reflexo de Sobressalto/efeitos dos fármacos , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia
9.
Sci Rep ; 8(1): 2860, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29434252

RESUMO

The hot injection synthesis of nanomaterials is a highly diverse and fundamental field of chemical research, which has shown much success in the bottom up approach to nanomaterial design. Here we report a synthetic strategy for the production of anisotropic metal chalcogenide nanomaterials of different compositions and shapes, using an optimised hot injection approach. Its unique advantage compared to other hot injection routes is that it employs one chemical to act as many agents: high boiling point, viscous solvent, reducing agent, and surface coordinating ligand. It has been employed to produce a range of nanomaterials, such as CuS, Bi2S3, Cu2-xSe, FeSe2, and Bi4Se3, among others, with various structures including nanoplates and nanosheets. Overall, this article will highlight the excellent versatility of the method, which can be tuned to produce many different materials and shapes. In addition, due to the nature of the synthesis, 2D nanomaterial products are produced as monolayers without the need for exfoliation; a significant achievement towards future development of these materials.

10.
Neuropharmacology ; 53(1): 113-24, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17559891

RESUMO

PDE1B is a calcium-dependent cyclic nucleotide phosphodiesterase that is highly expressed in the striatum. In order to investigate the physiological role of PDE1B in the central nervous system, PDE1B knockout mice (C57BL/6N background) were assessed in behavioral tests and their brains were assayed for monoamine content. In a variety of well-characterized behavioral tasks, including the elevated plus maze (anxiety-like behavior), forced swim test (depression-like behavior), hot plate (nociception) and two cognition models (passive avoidance and acquisition of conditioned avoidance responding), PDE1B knockout mice performed similarly to wild-type mice. PDE1B knockout mice showed increased baseline exploratory activity when compared to wild-type mice. When challenged with amphetamine (AMPH) and methamphetamine (METH), male and female PDE1B knockout mice showed an exaggerated locomotor response. Male PDE1B knockout mice also showed increased locomotor responses to higher doses of phencyclidine (PCP) and MK-801; however, this effect was not consistently observed in female knockout mice. In the striatum, increased dopamine turnover (DOPAC/DA and HVA/DA ratios) was found in both male and female PDE1B knockout mice. Striatal serotonin (5-HT) levels were also decreased in PDE1B knockout mice, although levels of the metabolite, 5HIAA, were unchanged. The present studies demonstrate increased striatal dopamine turnover in PDE1B knockout mice associated with increased baseline motor activity and an exaggerated locomotor response to dopaminergic stimulants such as methamphetamine and amphetamine. These data further support a role for PDE1B in striatal function.


Assuntos
Comportamento Animal/fisiologia , Química Encefálica/genética , Camundongos Knockout , Diester Fosfórico Hidrolases/deficiência , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Comportamento Animal/efeitos dos fármacos , Monoaminas Biogênicas/metabolismo , Química Encefálica/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 1 , Maleato de Dizocilpina/farmacologia , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout/genética , Camundongos Knockout/metabolismo , Camundongos Knockout/fisiologia , Atividade Motora/efeitos dos fármacos , Atividade Motora/genética , Fenciclidina/farmacologia , Fatores Sexuais , Natação
11.
Mol Cell Biol ; 13(6): 3255-65, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8388535

RESUMO

We have used the multifunctional transforming protein, simian virus 40 T antigen, as a probe to study the mechanisms of cell growth regulation in the intact organism. T antigen appears to perturb cell growth, at least in part, by stably interacting with specific cellular proteins that function to maintain normal cell growth properties. Experiments in cultured cells indicate that at least three distinct regions of simian virus 40 T antigen have roles in transformation. Two regions correlate with the binding of known cellular proteins, p53, pRB, and p107. A third activity, located near the amino terminus, has been defined genetically but not biochemically. By targeting expression of wild-type and mutant forms of T antigen to distinct cell types in transgenic mice, we have begun to systematically determine which activities play a role in tumorigenesis of each cell type. In this study, we sought to determine the role of the amino-terminal transformation function with such an analysis of the T-antigen mutant dl1135. This protein, which lacks amino acids 17 to 27, retains the p53-, pRB-, and p107-binding activities yet fails to transform cells in culture. To direct expression in transgenic mice, we used the lymphotropic papovavirus transcriptional signals that are specific for B and T lymphocytes and the choroid plexus epithelium of the brain. We show here that although defective in cell culture, dl1135 specifically induced the development of thymic lymphomas in the mouse. Expression of the protein was routinely observed in B- and T-lymphoid cells, although B-cell abnormalities were not observed. Choroid plexus tumors were observed only infrequently; however, dl1135 was not consistently expressed in this tissue. Within a given transgenic line, the penetrance of T-cell tumorigenesis was 100% but appeared to require secondary events, as judged from the clonal nature of the tumors. These experiments suggest that the amino-terminal region of T antigen has a role in the transformation of certain cell types (such as fibroblasts in culture and B lymphocytes) but is dispensable for the transformation of T lymphocytes.


Assuntos
Antígenos Transformantes de Poliomavirus/genética , Neoplasias Encefálicas/genética , Transformação Celular Viral/genética , Neoplasias do Plexo Corióideo/genética , Mutagênese , Vírus 40 dos Símios/genética , Neoplasias Esplênicas/genética , Neoplasias do Timo/genética , Animais , Anticorpos Monoclonais , Antígenos Transformantes de Poliomavirus/fisiologia , Sequência de Bases , Neoplasias Encefálicas/microbiologia , Divisão Celular , Neoplasias do Plexo Corióideo/microbiologia , Citometria de Fluxo , Depleção Linfocítica , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Reação em Cadeia da Polimerase , Mapeamento por Restrição , Deleção de Sequência , Neoplasias Esplênicas/microbiologia , Linfócitos T/citologia , Linfócitos T/imunologia , Timo/imunologia , Neoplasias do Timo/microbiologia
12.
Mol Cell Biol ; 17(5): 2401-12, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9111309

RESUMO

Heparin-binding epidermal growth factor (HB-EGF) gene transcription is rapidly activated in NIH 3T3 cells transformed by oncogenic Ras and Raf and mediates the autocrine activation of the c-Jun N-terminal kinases (JNKs) observed in these cells. A 1.7-kb fragment of the promoter of the murine HB-EGF gene linked to a luciferase reporter was strongly induced following activation of deltaRaf-1:ER, a conditionally active form of oncogenic human Raf-1. Promoter activation by deltaRaf-1:ER required a composite AP-1/Ets transcription factor binding site located between bp -974 and -988 upstream of the translation initiation site. In vivo genomic footprinting indicated that the basal level of occupancy of this composite AP-1/Ets element increased following deltaRaf-1:ER activation. Cotransfection of Ets-2 and p44 mitogen-activated protein (MAP) kinase expression vectors strongly potentiated HB-EGF promoter activation in response to deltaRaf-1:ER. Potentiated activation required both p44 MAP kinase catalytic activity and threonine 72 in the Pointed domain of Ets-2. Biochemical assays demonstrated the ability of the p42 and p44 MAP kinases to phosphorylate Ets-2 on threonine 72. Importantly, in intact cells, the kinetics of phosphorylation of Ets-2 on this residue closely mirror the activation of the p42 and p44 MAP kinases and the observed onset of HB-EGF gene transcription following deltaRaf-1:ER activation. These data firmly establish Ets-2 as a direct target of the Raf-MEK-MAP kinase signaling pathway and strongly implicate Ets-2 in the regulation of HB-EGF gene expression.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Proteínas de Ligação a DNA , Fator de Crescimento Epidérmico/metabolismo , Heparina/metabolismo , Proteínas Serina-Treonina Quinases/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/farmacologia , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Transativadores/farmacologia , Fatores de Transcrição , Células 3T3 , Animais , Sequência de Bases , Pegada de DNA , Ativação Enzimática , Regulação da Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Dados de Sequência Molecular , Fosforilação , Mutação Puntual , Regiões Promotoras Genéticas , Proteína Proto-Oncogênica c-ets-2 , Proteínas Proto-Oncogênicas c-raf , Fator de Transcrição AP-1/metabolismo
13.
Mol Cell Biol ; 16(4): 1458-70, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8657119

RESUMO

To elucidate signal transduction pathways leading to neuronal differentiation, we have investigated a conditionally immortalized cell line from rat hippocampal neurons (H19-7) that express a temperature sensitive simian virus 40 large T antigen. Treatment of H19-7 cells with the differentiating agent basic fibroblast growth factor at 39 degrees C, the nonpermissive temperature for T function, resulted in the activation of c-Raf-1, MEK, and mitogen-activated protein (MAP) kinases (ERK1 and -2). To evaluate the role of Raf-1 in neuronal cell differentiation, we stably transfected H19-7 cells with v-raf or an oncogenic human Raf-1-estrogen receptor fusion gene (deltaRaf-1:ER). deltaRaf-1:ER transfectants in the presence of estradiol for 1 to 2 days expressed a differentiation phenotype only at the nonpermissive temperature. However, extended exposure of the deltaRaf-1:ER transfectants to estradiol or stable expression of the v-raf construct yielded cells that extended processes at the permissive as well as the nonpermissive temperature, suggesting that cells expressing the large T antigen are capable of responding to the Raf differentiation signal. deltaRaf-1:ER, MEK, and MAP kinase activities in the deltaRaf-1:ER cells were elevated constitutively for up to 36 h of estradiol treatment at the permissive temperature. At the nonpermissive temperature, MEK and ERKs were activated to a significantly lesser extent, suggesting that prolonged MAP kinase activation may not be sufficient for differentiation. To test this possibility, H19-7 cells were transfected or microinjected with constitutively activated MEK. The results indicate that prolonged activation of MEK or MAP kinases (ERK1 and -2) is not sufficient for differentiation of H19-7 neuronal cells and raise the possibility that an alternative signaling pathway is required for differentiation of H19-7 cells by Raf.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Hipocampo/citologia , MAP Quinase Quinase Quinase 1 , Proteínas Quinases Ativadas por Mitógeno , Neurônios/citologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Oncogênicas de Retroviridae/genética , Animais , Antígenos Transformantes de Poliomavirus/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Estradiol/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Hipocampo/metabolismo , Humanos , Proteína Quinase 1 Ativada por Mitógeno , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Oncogênicas v-raf , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Ratos , Receptores de Estrogênio/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Oncogênicas de Retroviridae/metabolismo , Transdução de Sinais , Temperatura , Transfecção
14.
Oncogene ; 19(4): 526-36, 2000 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-10698522

RESUMO

The Raf/MEK/MAP kinase cascade plays a critical role in transducing growth signals from activated cell surface receptors. Using deltaMEK1:ER, a conditionally-active form of MEK1, we demonstrate the ability of this dual specificity protein kinase to abrogate the cytokine-dependency of the human and murine hematopoietic cells lines TF-1, FDC-P1 and FL5.12. Cytokine-independent cells were obtained from TF-1, FDC-P1 and FL5.12 cells at frequencies of 2.5 x 10(-3), 5 x 10(-5) and 10(-7) respectively, indicating that not all cells expressing deltaMEK1:ER were factor-independent. In general, cells that were converted to a cytokine-independent phenotype displayed a higher level of MAP kinase activity in response to deltaMEK1:ER activation than those that remained cytokine-dependent. deltaME-K1:ER-responsive cells could be maintained long-term in the presence of beta-estradiol as well as the estrogen-receptor antagonist 4-Hydroxy-Tamoxifen and the anti-estrogen ICI 164383. Removal of hormone led to the rapid cessation of cell growth in a manner similar to that observed when cytokine is withdrawn from the parental cells. Treatment of deltaMEKI:ER-responsive cells with a specific and selective inhibitor, PD98059, prevented growth in response to beta-estradiol. GM-CSF mRNA transcripts were detected in the MEK1-responsive cells indicating that the activated deltaMEK1:ER may induce a pathway leading to autocrine proliferation. Treatment of MEK1-responsive cells with an anti-GM-CSF antibody, but not a control antibody, suppressed cell growth. The cell lines described here will be useful for elaborating the ability of the MAP kinase pathway to regulate cell proliferation in hematopoietic cells.


Assuntos
Comunicação Autócrina , Transformação Celular Neoplásica/genética , Células-Tronco Hematopoéticas/enzimologia , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Anticorpos Monoclonais/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Citocinas/farmacologia , Ativação Enzimática , Indução Enzimática , Estradiol/farmacologia , Flavonoides/farmacologia , Genes Sintéticos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , MAP Quinase Quinase 1 , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/biossíntese , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutagênese Sítio-Dirigida , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/fisiologia , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Transfecção
15.
Trends Pharmacol Sci ; 12(12): 462-7, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1792690

RESUMO

The vascular endothelium is a remarkably heterogeneous organ. In addition to well-characterized anatomical diversity in situ, specific differences are increasingly being recognized between surface antigens on endothelial cells from different tissues, including absence of the classic endothelial marker factor VIII-related antigen (von Willebrand factor) from many endothelial cells. Microvascular heterogeneity extends to properties of endothelial cells thought to be involved in tumour angiogenesis and metastasis, such as growth factor responsiveness and expression of cell adhesion molecules. These findings are not only of relevance to the unambiguous identification and characterization of cultured endothelial cells, but, as Roy Bicknell and colleagues discuss, may explain the phenomenon of preferential organ tumour metastasis and provide novel opportunities for antitumour therapy.


Assuntos
Endotélio Vascular/fisiologia , Metástase Neoplásica/patologia , Especificidade de Órgãos/fisiologia , Adesão Celular/fisiologia , Endotélio Vascular/citologia , Humanos , Microcirculação , Células Neoplásicas Circulantes/patologia
16.
J Leukoc Biol ; 70(1): 87-95, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11435490

RESUMO

Previously, we showed that NO induces thymocyte apoptosis via a caspase-1-dependent mechanism [(1) ]. In the present study, we investigated the role of heme oxygenase, catalase, bax, and p53 in this process. The NO donor, S-nitroso-N-acetyl penicillamine (SNAP), induced DNA fragmentation in thymocytes in a time- and concentration-dependent way. SNAP (100 microM) induced 50--60% apoptosis; higher doses did not increase the rate of apoptosis significantly. SNAP decreased catalase and heme iron (Fe) levels without affecting superoxide dismutase, glutathione, or total Fe stores in thymocytes. SNAP significantly increased the expression of heme oxygenase 1 (HSP-32), p53, and bax but not bcl-2. Treatment with the heme oxygenase inhibitor, tin protoporphyrin IX inhibited SNAP-induced thymocyte apoptosis. Furthermore, thymocytes from p53 null mice were resistant to NO-induced apoptosis. Our data suggest that NO may induce its cytotoxic effects on thymocytes by modulating heme oxygenase and catalase activity as well as up-regulating pro-apoptotic proteins p53 and bax.


Assuntos
Apoptose/efeitos dos fármacos , Óxido Nítrico/farmacologia , Timo/efeitos dos fármacos , Proteína Supressora de Tumor p53/fisiologia , Animais , Apoptose/fisiologia , Catalase/metabolismo , Técnicas de Cocultura , Indução Enzimática/efeitos dos fármacos , Eritrócitos/citologia , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Heme/metabolismo , Heme Oxigenase (Desciclizante)/biossíntese , Heme Oxigenase-1 , Ferro/metabolismo , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Doadores de Óxido Nítrico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética , S-Nitroso-N-Acetilpenicilamina , Superóxido Dismutase/metabolismo , Timo/citologia , Timo/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética , Proteína X Associada a bcl-2
17.
Mar Environ Res ; 59(4): 367-80, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15589987

RESUMO

When Hurricane Iniki struck the Hawaiian Islands in September 1992, it provided a rare opportunity to examine the immediate effects of a hurricane on two intertidal benthic communities off the reefs of O'ahu, Hawai'i. The Niu Beach site contained large, obvious aggregations of the tube building polychaete Diopatra dexiognatha, and the Wailupe Beach site was without obvious tubiculous fauna at the surface. Ten replicate sediment cores were taken before and after the hurricane with a 7.6 cm PVC corer and organisms were identified to family and enumerated. There were no substantial depletions or loss of taxa after the hurricane. Oligochaetes were the most dominant taxa pre-and post-hurricane. The abundance of all dominant polychaete families increased post-hurricane. The three most abundant polychaetes were capitellids and D. dexiognatha (Onuphidae) at Niu Beach and Pygospio muscularis (Spionidae) at Wailupe Beach. We suggest that D. dexiognatha and P. muscularis help stabilize the sediments since they both form dense tube mats while capitellids and oligochaetes are considered highly adaptive surface burrowers that can take advantage of newly disturbed sediments. Overall, there was no substantial effect observed on the intertidal fauna exposed to this severe disturbance. It is suggested here that invertebrate communities in this area are adapted to survive and thrive in high-energy environments and possibly benefit from dense aggregations of tube building polychaetes.


Assuntos
Desastres , Poliquetos/crescimento & desenvolvimento , Animais , Classificação , Ecossistema , Sedimentos Geológicos , Havaí , Dinâmica Populacional
18.
Neuropharmacology ; 95: 434-47, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25959066

RESUMO

It has been suggested that amphetamine abuse and withdrawal mimics the diverse nature of bipolar disorder symptomatology in humans. Here, we determined if a single paradigm of amphetamine sensitization would be sufficient to produce both manic- and depressive-related behaviors in mice. CD-1 mice were subcutaneously dosed for 5 days with 1.8 mg/kg d-amphetamine or vehicle. On days 6-31 of withdrawal, amphetamine-sensitized (AS) mice were compared to vehicle-treated (VT) mice on a range of behavioral and biochemical endpoints. AS mice demonstrated reliable mania- and depression-related behaviors from day 7 to day 28 of withdrawal. Relative to VT mice, AS mice exhibited long-lasting mania-like hyperactivity following either an acute 30-min restraint stress or a low-dose 1 mg/kg d-amphetamine challenge, which was attenuated by the mood-stabilizers lithium and quetiapine. In absence of any challenge, AS mice showed anhedonia-like decreases in sucrose preference and depression-like impairments in the off-line consolidation of motor memory, as reflected by the lack of spontaneous improvement across days of training on the rotarod. AS mice also demonstrated a functional impairment in nest building, an ethologically-relevant activity of daily living. Western blot analyses revealed a significant increase in methylation of histone 3 at lysine 9 (H3K9), but not lysine 4 (H3K4), in hippocampus of AS mice relative to VT mice. In situ hybridization for the immediate-early gene activity-regulated cytoskeleton-associated protein (Arc) further revealed heightened activation of corticolimbic structures, decreased functional connectivity between frontal cortex and striatum, and increased functional connectivity between the amygdala and hippocampus of AS mice. The effects of amphetamine sensitization were blunted in C57BL/6J mice relative to CD-1 mice. These results show that a single amphetamine sensitization protocol is sufficient to produce behavioral, functional, and biochemical phenotypes in mice that are relevant to bipolar disorder.


Assuntos
Transtorno Bipolar/induzido quimicamente , Córtex Cerebral/efeitos dos fármacos , Dextroanfetamina/administração & dosagem , Modelos Animais de Doenças , Sistema Límbico/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/psicologia , Anedonia , Animais , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/fisiopatologia , Córtex Cerebral/metabolismo , Sistema Límbico/metabolismo , Compostos de Lítio/farmacologia , Masculino , Consolidação da Memória , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora , Comportamento de Nidação , Vias Neurais/efeitos dos fármacos , Vias Neurais/metabolismo , Psicotrópicos/farmacologia , Fumarato de Quetiapina/farmacologia , Restrição Física , Especificidade da Espécie , Estresse Psicológico/fisiopatologia , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Síndrome de Abstinência a Substâncias/fisiopatologia
19.
Gene ; 238(2): 301-13, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10570958

RESUMO

Wnt proteins influence many aspects of embryonic development, and their activity is regulated by several secreted antagonists, including the Xenopus Dickkopf-1 (xDkk-1) protein. xDkk-1 inhibits Wnt activities in Xenopus embryos and may play a role in induction of head structures. Here, we characterize a family of human Dkk-related genes composed of Dkk-1, Dkk-2, Dkk-3, and Dkk-4, together with a unique Dkk-3 related protein termed Soggy (Sgy). hDkks 1-4 contain two distinct cysteine-rich domains in which the positions of 10 cysteine residues are highly conserved between family members. Sgy is a novel secreted protein related to Dkk-3 but which lacks the cysteine-rich domains. Members of the Dkk-related family display unique patterns of mRNA expression in human and mouse tissues, and are secreted when expressed in 293T cells. Furthermore, secreted hDkk-2 and hDkk-4 undergo proteolytic processing which results in cleavage of the second cysteine-rich domain from the full-length protein. Members of the human Dkk-related family differ not only in their structures and expression patterns, but also in their abilities to inhibit Wnt signaling. hDkk-1 and hDkk-4, but not hDkk-2, hDkk-3 or Sgy, suppress Wnt-induced secondary axis induction in Xenopus embryos. hDkk-1 and hDkk-4 do not block axis induction triggered either by Xenopus Dishevelled (Xdsh) or Xenopus Frizzled-8 (Xfz8), both of which function to transduce signals from Wnt ligands. Thus, hDkks 1 and 4 may inhibit Wnt activity by a mechanism upstream of Frizzled. Our findings highlight the structural and functional heterogeneity of human Dkk-related proteins.


Assuntos
Família Multigênica , Proteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Dados de Sequência Molecular , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo , RNA Mensageiro/genética , Homologia de Sequência de Aminoácidos , Xenopus/embriologia , Proteínas de Xenopus
20.
Transplantation ; 40(1): 12-7, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3892791

RESUMO

We have produced stable murine antibody-facilitated (AF) chimeras by the simultaneous injection of P1 bone marrow cells and anti-P2 monoclonal antibody into normal (unirradiated) adult (P1 X P2)F1 recipients. These AF chimeras are healthy, long-lived, and exhibit no overt signs of graft-versus-host disease. They are immunocompetent and tolerant of host, P2-encoded alloantigens. Donor cell engraftment and takeover, monitored by glucosephosphate isomerase isozyme patterns, is usually complete (greater than 95%) in the peripheral blood, bone marrow, and hemopoietic stem cell compartments of long-term (greater than 3 months posttransplantation) AF chimeras. We report here, however, that splenic, lymph node, and thymic leukocytes of AF chimeras represent donor/host chimeric populations. Spleen cell populations of AF chimeras exhibit substantial chimera-to-chimera variation in the preponderant residual host cell type(s) present. Our interpretations of the implications of these findings are discussed.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Transplante de Medula Óssea , Transfusão de Linfócitos , Quimera por Radiação , Animais , Medula Óssea/efeitos da radiação , Células da Medula Óssea , Tolerância Imunológica , Contagem de Leucócitos , Linfonodos/citologia , Linfócitos/classificação , Linfócitos/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Baço/citologia , Timo/citologia
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