Addition of 5-fluorouracil to doxorubicin-paclitaxel sequence increases caspase-dependent apoptosis in breast cancer cell lines

INTRODUCTION: The aim of the study was to evaluate the activity of a combination of doxorubicin (Dox), paclitaxel (Pacl) and 5-fluorouracil (5-FU), to define the most effective schedule, and to investigate the mechanisms of action in human breast cancer cells. METHODS: The study was performed on MCF-7 and BRC-230 cell lines. The cytotoxic activity was evaluated by sulphorhodamine B assay and the type of drug interaction was assessed by the median effect principle. Cell cycle perturbation and apoptosis were evaluated by flow cytometry, and apoptosis-related marker (p53, bcl-2, bax, p21), caspase and thymidylate synthase (TS) expression were assessed by western blot. RESULTS: 5-FU, used as a single agent, exerted a low cytotoxic activity in both cell lines. The Dox→Pacl sequence produced a synergistic cytocidal effect and enhanced the efficacy of subsequent exposure to 5-FU in both cell lines. Specifically, the Dox→Pacl sequence blocked cells in the G2-M phase, and the addition of 5-FU forced the cells to progress through the cell cycle or killed them. Furthermore, Dox→Pacl pretreatment produced a significant reduction in basal TS expression in both cell lines, probably favoring the increase in 5-FU activity. The sequence Dox→Pacl→48-h washout→5-FU produced a synergistic and highly schedule-dependent interaction (combination index < 1), resulting in an induction of apoptosis in both experimental models regardless of hormonal, p53, bcl-2 or bax status. Apoptosis in MCF-7 cells was induced through caspase-9 activation and anti-apoptosis-inducing factor hyperexpression. In the BRC-230 cell line, the apoptotic process was triggered only by a caspase-dependent mechanism. In particular, at the end of the three-drug treatment, caspase-8 activation triggered downstream executioner caspase-3 and, to a lesser degree, caspase-7. CONCLUSION: In our experimental models, characterized by different biomolecular profiles representing the different biology of human breast cancers, the schedule Dox→Pacl→48-h washout→5-FU was highly active and schedule-dependent and has recently been used to plan a phase I/II clinical protocol

Biological associations of color variation in the Indo-Pacific swimming crab Charybdis hellerii

A marine biological invasion is a natural process accelerated by human activities, and the crab Charybdis hellerii is an example of a globally widespread invasive species. This study evaluated color variation in C. hellerii and its relationship to the sex, size and sexual maturity of these crabs, and compared the efficiency of a freeware digital image-editing program with a commercially available program. The color of the individuals was analyzed using standardized digital images. The color pattern varied significantly with size; smaller and immature individuals were darker than larger and mature ones. The female abdomen changed in morphology and color with sexual maturity, becoming wider and orange-colored. There was no statistical difference in the color values between males and females and immature males did not show morphological or color differences in their abdomen. This study highlights the possible relationships of the color and physiological state of the reproductive system, which could help in future studies of behavior, avoiding the need to dissect and/or remove individuals from nature for assessment of sexual maturity. The freeware program showed the same efficiency in digital image analysis as a widely known commercial program.Invasões biológicas marinhas são processos naturais acelerados pelas atividades humanas e o siri Charybdis hellerii é um exemplo de espécies invasoras distribuídas pelo mundo. Este estudo avaliou a variação de cor em C. hellerii e sua relação com o sexo, tamanho e maturidade sexual desses indivíduos, e comparou a eficiência de um programa de edição de imagem de licença livre com um programa disponível comercialmente. A cor dos indivíduos foi analisada usando imagem digital padronizada. O padrão de cor variou significantemente com o tamanho; indivíduos pequenos e imaturos são mais escuros que indivíduos maiores e maduros. Os abdomens das fêmeas mudaram morfologicamente e na cor de acordo com a maturidade sexual, tornando-se mais largos e de cor alaranjada. Não houve diferença estatística nos valores de cor entre machos e fêmeas, e machos imaturos não mostraram diferenças morfológicas e de cor em seus abdomens. Este estudo ressalta as possíveis relações da cor e estado fisiológico do sistema reprodutivo o que pode ajudar futuramente em estudos comportamentais, evitando a necessidade de dissecar e/ou remover indivíduos da natureza para avaliar a maturidade sexual. O programa livre obteve a mesma eficiência na análise de imagem digital em relação ao programa comercial amplamente conhecido.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal do Amazonas (UFAM), Programa de Pós-Graduação em Ciência e Tecnologia para Recursos Amazônicos (PPGCTRA), Instituto de Ciências Exatas e Tecnologia (ICET), Rua Nossa Senhora do Rosário, 3863, 69103-128 Itacoatiara, AM, BrasilUniversidade Estadual Paulista (UNESP), Faculdade de Ciências Agrárias e Veterinárias, Centro de Aquicultura, Instituto de Estudos Avançados do Mar, Departamento de Biologia Aplicada, Laboratório de Morfologia de Invertebrados, Campus de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane, s/n, 14884-900 Jaboticabal, SP, BrasilUniversidade de São Paulo (USP), Instituto Oceanográfico (IOUSP), Departamento de Oceanografia Biológica (DOB), Praça do Oceanográfico, 191, 05508-120 São Paulo, SP, BrasilUniversidade Estadual Paulista (UNESP), Faculdade de Ciências Agrárias e Veterinárias, Centro de Aquicultura, Instituto de Estudos Avançados do Mar, Departamento de Biologia Aplicada, Laboratório de Morfologia de Invertebrados, Campus de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane, s/n, 14884-900 Jaboticabal, SP, BrasilCNPq: 301240/2006-0CNPq: 308215/2010-9FAPESP: 2005/04707-5FAPESP: 2010/50188-

Electroweak parameters of the z0 resonance and the standard model

Contains fulltext : 124399.pdf (publisher's version ) (Open Access

Evaluation of transgenic tomato plants ectopically expressing the rice Osmyb4 gene

The rice Osmyb4 gene, coding for a MYB transcription factor, is expressed at low levels in rice coleoptiles under normal conditions and strongly induced at 4 \ub0C. Its overexpression in Arabidopsis thaliana plants increases biotic and abiotic stress tolerance and results in the accumulation of several metabolites, essential in defence response. The heterologous expression of the Myb4 transcription factor represents a promising potential approach to improve stress tolerance in crops, avoiding endogenous mechanisms that often co-suppress the transgene of interest. In order to explore the potential of the Osmyb4 gene to enhance tolerance toward multiple stresses in different host plant genomes, we generated transgenic tomato (Solanum lycopersicum L. cv. Tondino) plants. Like Arabidopsis, tomato plants overexpressing Osmyb4 acquired a higher tolerance to drought stress and to virus disease. However, the transgenic plants did not appear to be more cold tolerant than the WT, in any tested condition. The data obtained indicate that the specificity and the degree of Osmyb4 activity depend on the host genomic background

Computed tomographic features of incomplete ossification of the canine humeral condyle

Objectives - To describe computed tomographic (CT) features of canine elbows with incomplete ossification of the humeral condyle (IOHC) and investigate co-existing incongruence in the elbow joint. Study Design - Case control study. Animals - Dogs with IOHC (n=20; 38 elbows) and 25 normal elbows. Methods - Elbows with IOHC and normal elbows were assessed by CT. Standardized dorsal and sagittal reconstructions were created at 3 levels using image analysis software to obtain single measurements of the humero-radial and humero-ulnar joint spaces. On dorsal plane reconstructions, joint space measurements were obtained at the center point of the humero-radial and humero-ulnar articulations. Joint incongruity was defined as the difference between the humero-radial and the humero-ulnar joint spaces. Results - Nineteen dogs (95%), all Spaniel breeds, had either bilateral IOHC demonstrable as a saw-toothed intercondylar complete or incomplete hypoattenuating defect with hyperattenuating margins, or IOHC with contralateral humeral condylar fracture (HCF). Joint incongruity values for IOHC were compared with those of normal elbows. Significant differences were noted at the levels of the medial coronoid apex (P &lt;.0001) and base (P &lt;.004) indicative of humero-ulnar incongruence. Evidence of medial coronoid disease in 10 elbows (26%) and degenerative joint disease in 30 elbows (79%) was also found. Conclusions - Presence of elbow incongruence may be an underlying factor in failure of ossification centers to fuse leading to IOHC. Clinical Relevance - IOHC is clearly defined by CT, and it should be considered in larger Spaniel breeds, with a chronic forelimb lameness or HCF