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2.
Eur J Cancer ; 46(12): 2242-52, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20580993

RESUMO

BACKGROUND AND AIM: There is a lack of instruments that focus on the specific health-related quality of life (HRQOL) issues that affect older people with cancer. The aim of this study was to develop a HRQOL questionnaire module to supplement the European Organisation for Research and Treatment of Cancer (EORTC) core questionnaire, the EORTC QLQ-C30 for older (>70years) patients with cancer. METHODS: Phases 1-3 were conducted in seven countries following modified EORTC Quality of Life Group guidelines for module development. Phase 1: potentially relevant issues were identified by a systematic literature review, a questionnaire survey of 17 multi-disciplinary health professionals and two rounds of qualitative interviews. The first round included 9 patients aged >70. The second round was a comparative series of interviews with 49 patients >70years with a range of cancer diagnoses and 40 patients aged 50-69years matched for gender and disease site. In Phase 2 the issues were formulated into a long provisional item list. This was administered in Phase 3 together with the QLQ-C30 to two further groups of cancer patients aged >70 (n=97) or 50-69years (n=85) to determine the importance, relevance and acceptability of each item. Redundant and duplicate items were removed; issues specific to the older group were selected for the final questionnaire. RESULTS: In Phase 1, 75 issues were identified. These were reduced in Phase 2 to create a 45 item provisional list. Phase 3 testing of the provisional list led to the selection of 15 items with good range of response, high scores of importance and relevance in the older patients. This resulted in the EORTC QLQ-ELD15, containing five conceptually coherent scales (functional independence, relationships with family and friends, worries about the future, autonomy and burden of illness). CONCLUSION: The EORTC QLQ-ELD15 in combination with the EORTC QLQ-C30 is ready for large-scale validation studies, and will assess HRQOL issues of most relevance and concern for older people with cancer across a wide range of cancer sites and treatment stages.


Assuntos
Neoplasias/psicologia , Qualidade de Vida , Inquéritos e Questionários , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade
3.
Assay Drug Dev Technol ; 5(4): 559-66, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17767424

RESUMO

Phosphorylation is central to signal transduction in living organisms. The specificity of phosphorylation ensures signaling fidelity. Understanding substrate specificity is essential for novel assay development in drug discovery. In this study, we have developed an innovative approach to study protein kinase and its substrate specificity. Using 24 micro parallel liquid chromatography, we studied the reaction kinetics for two different peptide substrates commonly associated with protein kinase A (PKA): Kemptide (Leu-Arg-Arg-Ala-Ser-Leu-Glu) and CREBtide (Lys-Arg-Arg-Glu-Ile-Leu-Ser-Arg-Arg-Pro-Ser-Tyr-Arg). The phosphorylation of each substrate was monitored in real time, and the kinetic parameters (V(max), K(m), k(cat), and k(cat) K(m)) were determined for a variety of initial conditions. The results from several kinetic experiments indicated that Kemptide had higher V(max) and k(cat) values compared to CREBtide under the same assay conditions. However, both substrates had a similar k cat)/K(m) value, suggesting that both substrates have similar specificity constants for PKA. We further analyzed the reaction kinetics of ATP for both PKA/substrate complexes. Interestingly, we found that there was a fivefold difference in the specificity constants for ATP affinity to the two complexes, suggesting that even though the sequence differences between the two substrates do not affect their independent interactions with PKA, the differences do have a secondary effect on each enzyme's interaction with ATP and significantly alter the ATP consumption and thus phosphorylation. This novel approach has a broad application for studying enzyme functions and enzyme/substrate specificity.


Assuntos
Cromatografia Líquida/métodos , Fosfotransferases/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/química , Interpretação Estatística de Dados , Cinética , Oligopeptídeos/isolamento & purificação , Peptídeos/isolamento & purificação , Fosforilação , Fosfotransferases/química , Ligação Proteica , Especificidade por Substrato , Temperatura
4.
J Pharmacol Exp Ther ; 306(3): 828-37, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12928523

RESUMO

Mitochondrial dysfunction has been identified as a possible early event in ischemia-reperfusion damage. The peripheral benzodiazepine receptor, a mitochondrial inner membrane protein, has already been proposed to play a role in mitochondrial regulation, although its exact function remains unclear. The aim of this work was to determine the role of peripheral benzodiazepine receptor in ischemia-reperfusion injury and to test the potential beneficial effect of a novel potent peripheral benzodiazepine receptor ligand, 7-chloro-N,N,5-trimethyl-4-oxo-3-phenyl-3,5-dihydro-4H-pyridazino[4,5-b]indole-1-acetamide (SSR180575). To characterize and link the mitochondrial, cellular, and cardiac consequences of ischemia-reperfusion, we examined the effects of SSR180575 in several in vitro and in vivo models of oxidative stress. Hydrogen peroxide decreased mitochondrial membrane potential, reduced oxidative phosphorylation capacities, and caused cytochrome c release, caspase 3 activation, and DNA fragmentation. SSR180575 (100 nM-1 microM) prevented all these effects. In perfused rat hearts, SSR180575 administered in vitro (100 nM-1 microM) or by oral pretreatment (3-30 mg/kg) greatly reduced the contractile dysfunction associated with ischemia-reperfusion. Furthermore, in anesthetized rats, SSR180575 (3-30 mg/kg p.o.) produced significant reductions in infarct size after coronary artery occlusion/reperfusion. In conclusion, we have demonstrated that peripheral benzodiazepine receptor play a major role in the regulation of cardiac ischemia-reperfusion injury and that SSR180575, a novel peripheral benzodiazepine receptor ligand, is of potential interest in these indications.


Assuntos
Traumatismos Cardíacos/etiologia , Mitocôndrias Cardíacas/fisiologia , Traumatismo por Reperfusão Miocárdica/complicações , Estresse Oxidativo/fisiologia , Receptores de GABA-A/fisiologia , Anestesia , Animais , Apoptose , Modelos Animais de Doenças , Traumatismos Cardíacos/patologia , Técnicas In Vitro , Masculino , Mioblastos Cardíacos/metabolismo , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Fosforilação Oxidativa , Coelhos , Ratos , Ratos Sprague-Dawley , Transfecção
5.
Cardiovasc Res ; 56(2): 293-302, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12393100

RESUMO

OBJECTIVE: Lower limb perfusion following arterial occlusion depends on the recruitment of collateral vessels. Blood flow through these collateral vessels may be jeopardized by hypersensitivity to vasoconstriction by serotonin (5-HT), as has been reported during hyperlipidemia and diabetes. Therefore the aim of this study was to determine the benefits of chronic treatment with SL65.0472, a mixed 5-HT(1B)/5-HT(2A) receptor antagonist, on lower limb ischemia in fatty fa/fa Zucker rats, a strain characterized by obesity, diabetes and hyperlipidemia. Comparison was made with lean control fa/+ Zucker rats. METHODS: SL65.0472 (3 mg/kg/day, n=16) or its vehicle (n=20) were administered orally for 13 days to male fatty fa/fa Zucker rats submitted to lower limb ischemia. Hindlimb ischemia was induced unilaterally by resection of the left femoral and external iliac arteries and embolization of the left internal iliac artery with microspheres. Distal perfusion was measured under mild anesthesia by laser Doppler imaging of both feet. The perfusion deficit (Delta%) was calculated before and 3, 7 and 14 days after induction of hindlimb ischemia. Twenty-four hours after the last administration of SL65.0472, muscular partial oxygen pressure, iliac blood flows, maximal vasodilatory reserve and the vasoreactivity to 5-HT were measured in both limbs. RESULTS: Chronic administration of SL65.0472 improved the distal perfusion from day 3. At day 14, the deficit of perfusion was limited to -36+/-7% in SL65.0472-treated animals vs. -70+/-6% in the vehicle-treated group (P<0.001) and was accompanied by a significant improvement of partial oxygen pressure in the ischemic limb (SL65.0472: 10.4+/-3.9 mmHg vs. vehicle: 3.5+/-1.1 mmHg, P<0.05). Maximal vasodilatory reserve tended to increase from 2.2+/-0.4 ml/min in the vehicle-treated group to 3.8+/-0.6 ml/min after SL65.0472. SL65.0472 markedly reduced 5-HT-mediated vasoconstriction, which was enhanced in the hypoperfused limb, without altering arterial pressure. Induction of hindlimb ischemia led to the overexpression of both 5-HT(1B) and 5-HT(2A) receptors only in the hypoperfused skeletal muscle as assessed by semi-quantitative RT-PCR. CONCLUSION: These results suggest that the recruitment of collateral vessels after the induction of hindlimb ischemia is significantly impaired in obese fa/fa Zucker rats due to a persistent vasoconstriction mediated by 5-HT and involving stimulation of 5-HT(1B) and/or 5-HT(2A) receptors.


Assuntos
Angiopatias Diabéticas/tratamento farmacológico , Membro Posterior/irrigação sanguínea , Isquemia/tratamento farmacológico , Piperazinas/uso terapêutico , Quinolinas/uso terapêutico , Antagonistas da Serotonina/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Ílio/irrigação sanguínea , Isquemia/fisiopatologia , Obesidade/fisiopatologia , Oxigênio/sangue , Pressão Parcial , Ratos , Ratos Zucker , Fluxo Sanguíneo Regional/efeitos dos fármacos , Serotonina/farmacologia , Vasoconstrição/efeitos dos fármacos
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