Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Asunto de la revista
País de afiliación
Intervalo de año de publicación
1.
BMC Cancer ; 21(1): 530, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33971844

RESUMEN

BACKGROUND: Osimertinib is a third generation tyrosine kinase inhibitor (TKI) that targets the epidermal growth factor receptor (EGFR) in lung cancer. However, although this molecule is not subject to some of the resistance mechanisms observed in response to first generation TKIs, ultimately, patients relapse because of unknown resistance mechanisms. New relevant non-small cell lung cancer (NSCLC) mice models are therefore required to allow the analysis of these resistance mechanisms and to evaluate the efficacy of new therapeutic strategies. METHODS: Briefly, PC-9 cells, previously modified for luciferase expression, were injected into the tail vein of mice. Tumor implantation and longitudinal growth, almost exclusively localized in the lung, were evaluated by bioluminescence. Once established, the tumor was treated with osimertinib until tumor escape and development of bone metastases. RESULTS: Micro-metastases were detected by bioluminescence and collected for further analysis. CONCLUSION: We describe an orthotopic model of NSCLC protocol that led to lung primary tumor nesting and, after osimertinib treatment, by metastases dissemination, and that allow the isolation of these small osimertinib-resistant micro-metastases. This model provides new biological tools to study tumor progression from the establishment of a lung tumor to the generation of drug-resistant micro-metastases, mimicking the natural course of the disease in human NSCLC patients.


Asunto(s)
Acrilamidas/uso terapéutico , Compuestos de Anilina/uso terapéutico , Neoplasias Óseas/secundario , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Micrometástasis de Neoplasia , Animales , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Mutación , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Environ Manage ; 52(4): 877-93, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23974902

RESUMEN

In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems.


Asunto(s)
Carbón Orgánico , Ecosistema , Agricultura Forestal/legislación & jurisprudencia , Población Rural , Árboles , Humanos , Madagascar
4.
Behav Brain Res ; 360: 120-127, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30521934

RESUMEN

This study aims to investigate the contribution of nigral dopaminergic (DA) cell loss, repeated exposure to DA medication and the combination of both to the development of neuropsychiatric symptoms observed in Parkinson's disease (PD). A bilateral 6-OHDA lesion of the substantia nigra pars compacta (SNc) was performed in rats. A set of animals was repeatedly administered with L-dopa (20 mg/kg/day) and benserazide (5 mg/kg/day) over 10 days starting from day 11 post-lesion. Behavioural testing was performed in week 3 post-lesion: novel object recognition (NOR), elevated plus maze (EPM) social interaction (SI) tests, and amphetamine-induced hyperlocomotion (AIH). Immunohistochemical analysis revealed a significant partial lesion (48%) in 6-OHDA versus sham rats. This lesion was not associated with motor impairment. However, lesioned rats displayed a significant deficit in the NOR, which was reversed by acute treatment with l-dopa/benserazide (12.5 mg/kg and 15 mg/kg respectively). Lesioned rats also displayed a deficit in the EPM which was not reversed by acute treatment with l-dopa. No difference was observed in the SI test or in the AIH assay. In all assays, no effect of chronic l-dopa exposure was observed. This study provides new insights into the neuropathophysiology associated with neuropsychiatric symptoms of PD. Our data strongly emphasises a not previously clearly identified critical role in cognition for the SNc. The results suggest that DA pathways were less directly involved in lesion-induced anxiety-like behaviour. We did not report any effect of chronic l-dopa exposure in the context of partial nigral cell loss.


Asunto(s)
Antiparkinsonianos/efectos adversos , Dopamina/metabolismo , Levodopa/efectos adversos , Trastornos de la Memoria/inducido químicamente , Enfermedad de Parkinson Secundaria/tratamiento farmacológico , Sustancia Negra/metabolismo , Anfetamina/toxicidad , Animales , Ansiedad/inducido químicamente , Benserazida/efectos adversos , Modelos Animales de Enfermedad , Miembro Anterior/fisiopatología , Trastornos Neurológicos de la Marcha/inducido químicamente , Relaciones Interpersonales , Locomoción/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Oxidopamina/toxicidad , Enfermedad de Parkinson Secundaria/inducido químicamente , Ratas , Ratas Sprague-Dawley , Reconocimiento en Psicología/efectos de los fármacos , Sustancia Negra/efectos de los fármacos , Simpaticolíticos/toxicidad , Tirosina 3-Monooxigenasa/metabolismo
5.
ACS Chem Neurosci ; 9(4): 762-772, 2018 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-29226687

RESUMEN

The 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated nonhuman primate (NHP) has been described as the most translatable model for experimental reproduction of L-dopa-induced dyskinesia (LID). However, from a drug discovery perspective, the risk associated with investment in this type of model is high due to the time and cost. The 6-hydroxydopamine (6-OHDA) rat dyskinesia model is recommended for testing compounds but relies on onerous, and nonstandard behavioral rating scales. We sought to develop a simplified and sensitive method aiming at assessing LID in the rat. The purpose was to validate a reliable tool providing earlier insight into the antidyskinetic potential of compounds in a time/cost-effective manner before further investigation in NHP models. Unilaterally 6-OHDA-lesioned rats were administered L-dopa (20 mg/kg) and benserazide (5 mg/kg) daily for 3 weeks starting 4 weeks postlesion, then coadministered with amantadine (20-30-40 mg/kg). An adapted rating scale was used to score LID frequency and a severity coefficient was applied depending on the features of the observed behavior. A gradual increase (about 3-fold) in LID score was observed over the 3 weeks of L-dopa treatment. The rating scale was sensitive enough to highlight a dose-dependent amantadine-mediated decrease (about 2.2-fold) in LID score. We validated a simplified method, able to reflect different levels of severity in the assessment of LID and, thus, provide a reliable tool for drug discovery.


Asunto(s)
Antiparkinsonianos/farmacología , Escala de Evaluación de la Conducta , Desarrollo de Medicamentos , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Amantadina/farmacología , Animales , Conducta Animal/efectos de los fármacos , Modelos Animales de Enfermedad , Desarrollo de Medicamentos/métodos , Enfermedad de Parkinson/tratamiento farmacológico , Ratas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA