RESUMO
The pore site in microtubules has been studied with the use of Hexaflutax, a fluorescent probe derived from paclitaxel. The compound is active in cells with similar effects to paclitaxel, indicating that the pore may be a target to microtubule stabilizing agents. While other taxanes bind microtubules in a monophasic way, thus indicating a single type of sites, Hexaflutax association is biphasic. Analysis of the phases indicates that two different binding sites are detected, reflecting two different modes of binding, which could arise from different arrangements of the taxane or fluorescein moieties in the pore. Association of the 4-4-20 antifluorescein monoclonal antibody-Hexaflutax complex to microtubules remains biphasic, thus indicating that the two phases observed arise from two different poses of the taxane moiety.
Assuntos
Antineoplásicos Fitogênicos/química , Microtúbulos/química , Taxoides/química , Moduladores de Tubulina/química , Antineoplásicos Fitogênicos/farmacologia , Sítios de Ligação , Humanos , Cinética , Microscopia Confocal , Microtúbulos/metabolismo , Modelos Moleculares , Taxoides/farmacologia , Termodinâmica , Moduladores de Tubulina/farmacologia , Células Tumorais CultivadasRESUMO
The efficacy of neurolytic coeliac plexus block (NCPB) guided by computerized tomography (CT) was compared with pharmacological therapy in the treatment of pain due to pancreatic cancer. The study involved 56 patients who were placed randomly in either a NCPB group and pharmacological therapy group. At day 1, 7, and 14, the visual analogue scale (VAS) pain scores of the NCPB group were significantly lower than those of the pharmacological therapy group (P < 0.01), with values of 1.3 +/- 0.8 versus 4.1 +/- 0.9, 1.7 +/- 1.1 versus 3.1 +/- 1.1, and 2.0 +/- 1.1 versus 2.9 +/- 0.6, respectively. However, the differences in the improvement of quality of life (QOL) between two groups were not statistically significant. Moreover, the dose of opioid was significantly lower in the patients of group 1 than those of group 2, while the complications related to NCPB were transient. We therefore concludes that CT-guided NCPB with alcohol is an effective and safe modality in the management of intractable pancreatic cancer pain.