Viability analysis and apoptosis induction of breast cancer cells in a microfluidic device: effect of cytostatic drugs

Breast cancer is the leading cause of cancer deaths among non-smoking women worldwide. At the moment the treatment regime is such that patients receive different chemotherapeutic and/or hormonal treatments dependent on the hormone receptor status, the menopausal status and age. However, in vitro sensitivity testing of tumor biopsies could rationalize and improve the choice of chemo- and hormone therapy. Lab-on-a-Chip devices, using microfluidic techniques, make detailed cellular analysis possible using fewer cells, enabling working with a patients’ own cells and performing chemo- and hormone sensitivity testing in an ex vivo setting. This article describes the development of two microfluidic devices made in poly(dimethylsiloxane) (PDMS) to validate the cell culture properties and analyze the chemosensitivity of MCF-7 cells (estrogen receptor positive human breast cancer cells) in response to the drug staurosporine (SSP). In both cases, cell viability was assessed using the life-stain Calcein-AM (CAAM) and the death dye propidium iodide (PI). MCF-7 cells could be statically cultured for up to 7 days in the microfluidic chip. A 30 min flow with SSP and a subsequent 24 h static incubation in the incubator induced apoptosis in MCF-7 cells, as shown by a disappearance of the aggregate-like morphology, a decrease in CAAM staining and an increase in PI staining. This work provides valuable leads to develop a microfluidic chip to test the chemosensitivity of tumor cells in response to therapeutics and in this way improve cancer treatment towards personalized medicine

Multidimensional evaluation of managed relocation

Managed relocation (MR) has rapidly emerged as a potential intervention strategy in the toolbox of biodiversity management under climate change. Previous authors have suggested that MR (also referred to as assisted colonization, assisted migration, or assisted translocation) could be a last-alternative option after interrogating a linear decision tree. We argue that numerous interacting and value-laden considerations demand a more inclusive strategy for evaluating MR. The pace of modern climate change demands decision making with imperfect information, and tools that elucidate this uncertainty and integrate scientific information and social values are urgently needed. We present a heuristic tool that incorporates both ecological and social criteria in a multidimensional decision-making framework. For visualization purposes, we collapse these criteria into 4 classes that can be depicted in graphical 2-D space. This framework offers a pragmatic approach for summarizing key dimensions of MR: capturing uncertainty in the evaluation criteria, creating transparency in the evaluation process, and recognizing the inherent tradeoffs that different stakeholders bring to evaluation of MR and its alternatives.Articl

Multidimensional evaluation of managed relocation

Managed relocation (MR) has rapidly emerged as a potential intervention strategy in the toolbox of biodiversity management under climate change. Previous authors have suggested that MR (also referred to as assisted colonization, assisted migration, or assisted translocation) could be a last-alternative option after interrogating a linear decision tree. We argue that numerous interacting and value-laden considerations demand a more inclusive strategy for evaluating MR. The pace of modern climate change demands decision making with imperfect information, and tools that elucidate this uncertainty and integrate scientific information and social values are urgently needed. We present a heuristic tool that incorporates both ecological and social criteria in a multidimensional decision-making framework. For visualization purposes, we collapse these criteria into 4 classes that can be depicted in graphical 2-D space. This framework offers a pragmatic approach for summarizing key dimensions of MR: capturing uncertainty in the evaluation criteria, creating transparency in the evaluation process, and recognizing the inherent tradeoffs that different stakeholders bring to evaluation of MR and its alternatives.Centre of Excellence for Invasion Biolog

The experience of making treatment decisions for women with early stage breast cancer: a diagrammatic representation

Article first published online: 8 JUN 2005Women who are making decisions about treatment for early stage breast cancer interact with a number of people when they are considering their treatment options and the impact breast cancer will have on their lives. Previous research has considered patient preferences for involvement in treatment decision-making and proposed factors that may influence breast cancer treatment decisions. However, to date, there has been a paucity of research focusing on the experience of making treatment decisions from the women's perspective. The aim of this paper is to describe the relationships between the women, the medical practitioners and other people, and to consider features that may be influential in the experience of making treatment decisions. Two models are proposed to represent concepts that are linked to the experience of making treatment decisions. The first model proposed has been formulated to represent factors that may influence the treatment decision. The second model highlights aspects of the women's lives that may be affected. This paper discusses concepts that are presented in the conceptual models and makes suggestions for future studies relating to the experience of making treatment decisions for women with breast cancer

Choice of grazed herbage or maize silage by lactating dairy cows: influence of sward height and concentrate level Preferência por pastagem ou silagem de milho por vacas leiteiras em lactação: influência da altura do pasto e do nível de concentrado

The preference of lactating dairy cows for grazed herbage or maize silage (MS), simultaneously offered ad libitum in the field, was examined at two sward heights (SH 4-6 and 8-10cm) and two concentrate levels (CL 0 and 6kg day-1) in a 2x2 factorial arrangement within a completely randomised experimental design. The experiment lasted 35 days and was carried out in spring using 24 multiparous Holstein Friesian cows. On average, the cows proportionately spent more time grazing than eating MS (0.85:0.15) and even though the higher rate of intake (RI) of dry matter (DM) of MS compared with grazed herbage (76 versus 26g DM min-1), the proportion of total DM intake as herbage was higher compared to that of MS (0.56:0.44). The higher crude protein and low fibre content of grazed herbage appeared to have a higher priority of choice than RI, as the cows chose to graze for longer (grazing time 385 min, MS feeding time 67min) despite the lower RI of herbage. The low proportion MS intake indicated that RI was a secondary factor of choice. Concentrate supplementation had a greater depressing effect on herbage intake than on MS intake. These results suggest that the animals reduce the intake of feed with lower RI when the labor associated to eat is decreased. The factors influencing the choice for herbage over maize silage remain unclear.<br>A preferência de vacas leiteiras em lactação por pasto ou silagem de milho (SM) oferecidas ad libitum simultaneamente no pasto foi avaliada quanto a duas alturas de pastagem (4-6 e 8-10cm) e dois níveis de concentrado (0 e 6kg dia-1), em um arranjo fatorial 2x2 dentro de um delineamento inteiramente ao acaso. O experimento, com duração de 35 dias, foi executado na primavera utilizando 24 vacas multíparas da raça Holandesa. As vacas passaram, em média, proporcionalmente mais tempo pastando do que comendo SM (0,85:0,15) e, mesmo considerando a maior taxa de consumo (TC) de matéria seca (MS) de SM comparada com a da pastagem (76 versus 26g MS min-1), a proporção do total do consumo de MS como pastagem foi mais alta comparada com aquela da SM (0,56:0,44). A proteína crua mais alta e o menor conteúdo de fibra da pastagem pareceram ter prioridade na escolha pelos animais do que a TC, pois as vacas preferiram pastar por mais tempo (tempo de pastejo = 385min, tempo para comer SM = 67min), não obstante ter havido menor TC na pastagem. A baixa proporção de consumo de SM indicou que a TC foi um fator secundário na preferência dos animais. A suplementação concentrada teve maior efeito depressor no consumo de pastagem que o consumo de SM. Estes resultados sugerem que a prioridade dos animais, quando o trabalho associado com o comer é reduzido, é o de diminuir o consumo de alimento com menor TC. Os fatores que influenciaram a preferência por pastagem sobre silagem de milho ainda não são totalmente claros