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3.
Proteomics ; 11(10): 1985-2002, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21500340

RESUMO

Aphids are major insect pests of cereal crops, acting as virus vectors as well as causing direct damage. The responses of wheat to infestation by cereal aphid (Sitobion avenae) were investigated in a proteomic analysis. Approximately, 500 protein spots were reproducibly detected in the extracts from leaves of wheat seedlings after extraction and 2-DE. Sixty-seven spots differed significantly between control and infested plants following 24 h of aphid feeding, with 27 and 11 up-regulated, and 8 and 21 down-regulated, in local or systemic tissues, respectively. After 8 days, 80 protein spots differed significantly between control and aphid treatments with 13 and 18 up-regulated and 27 and 22 down-regulated in local or systemic tissues, respectively. As positive controls, plants were treated with salicylic acid or methyl jasmonate; 81 and 37 differentially expressed protein spots, respectively, were identified for these treatments. Approximately, 50% of differentially expressed protein spots were identified by PMF, revealing that the majority of proteins altered by aphid infestation were involved in metabolic processes and photosynthesis. Other proteins identified were involved in signal transduction, stress and defence, antioxidant activity, regulatory processes, and hormone responses. Responses to aphid attack at the proteome level were broadly similar to basal non-specific defence and stress responses in wheat, with evidence of down-regulation of insect-specific defence mechanisms, in agreement with the observed lack of aphid resistance in commercial wheat lines.


Assuntos
Afídeos/metabolismo , Interações Hospedeiro-Parasita/fisiologia , Doenças das Plantas/parasitologia , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Triticum/metabolismo , Acetatos/farmacologia , Animais , Ciclopentanos/farmacologia , Eletroforese em Gel Bidimensional , Oxilipinas/farmacologia , Mapeamento de Peptídeos , Folhas de Planta/química , Proteínas de Plantas/análise , Proteínas de Plantas/classificação , Proteoma/química , Ácido Salicílico/farmacologia , Plântula/metabolismo , Plântula/parasitologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Estresse Fisiológico
4.
J Xray Sci Technol ; 19(4): 521-30, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-25214384

RESUMO

INTRODUCTION: In this communication we report on a novel non-invasive methodology in utilizing "soft" energy diagnostic X-rays to indirectly activate a photo-agent utilized in photodynamic therapy (PDT): Photofrin II (Photo II) through X-ray induced luminescence from Gadolinium Oxysulfide (20 micron dimension) particles doped with Terbium: Gd_{2}O_{2}S:Tb. Photodynamic agents such as Photo II utilized in PDT possess a remarkable property to become preferentially retained within the tumor's micro-environment. Upon the photo-agent's activation through (visible light) photon absorption, the agents exert their cellular cytotoxicity through type I and type II pathways through extensive generation of reactive oxygen species (ROS); namely, singlet oxygen ^{1}O_{2}, superoxide anion O_{2}^{-}, and hydrogen peroxide H_{2}O_{2}, within the intra-tumoral environment. Unfortunately, due to shallow visible light penetration depth (∼ 2 mm to 5 mm) in tissues, the current PDT strategy has largely been restricted to the treatment of surface tumors, such as the melanomas. Additional invasive strategies through optical fibers are currently utilized in getting the visible light into the intended deep seated targets within the body for PDT. METHODS: X-ray induced visible luminescence from Gd_{2}O_{2}S:Tb particles were spectroscopically characterized, and the potential in-vitro cellular cytotoxicity of Gd_{2}O_{2}S:Tb particles on human glioblastoma cells (due to 48 Hrs Gd_{2}O_{2}S:Tb particle exposure) was screened through the MTS cellular metabolic assay. In-vitro human glioblastoma cellular exposures in presence of Photo II with Gd_{2}O_{2}S:Tb particles were performed in the dark in sterile 96 well tissue culture plates, and the corresponding changes in the metabolic activities of the glioblastoma due to 15 minutes of (diagnostic energy) X-ray exposure was determined 48 Hrs after treatment through the MTS assay. RESULTS: Severe suppression (> 90% relative to controls) in the cellular metabolic activity of human glioblastoma was measured due to the treatment of clinically relevant concentrations of 20 µg/ml Photo II, with Gd_{2}O_{2}S:Tb particles, and (120 kVp) diagnostic X-rays. Taken together, the in-vitro findings herein provide the basis for future studies in determining the safety and efficacy of this non-invasive X-ray induced luminescence strategy in activating photo-agent in deep seated tumors.


Assuntos
Éter de Diematoporfirina , Metais Terras Raras/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Éter de Diematoporfirina/química , Éter de Diematoporfirina/farmacologia , Éter de Diematoporfirina/efeitos da radiação , Gadolínio , Humanos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/efeitos da radiação
17.
Minn Med ; 97(3): 14-6, 18, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24720063
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