Raja Venkatasubramanian

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The effectiveness of chemotherapeutic drugs in tumors is reduced by multiple effects including drug diffusion and variable susceptibility of local cell populations. We hypothesized that quantifying the interactions between drugs and tumor microenvironments could be used to identify more effective anti-cancer strategies. To test this hypothesis we created a(More)
Diffusion limitations in tumors create regions that are deficient in essential nutrients and contain a large number of quiescent and dying cells. Chemotherapeutic compounds are not effective against quiescent cells and therefore have reduced efficacy against tumors with extensive quiescence. We have formulated a mathematical model that predicts the extent(More)
The spatial arrangement of cellular metabolism in tumor tissue critically affects the treatment of cancer. However, little is known about how diffusion and cellular uptake relate to intracellular metabolism and cell death in three dimensions. To quantify these mechanisms, fluorescent microscopy and multicellular tumor cylindroids were used to measure pH and(More)
www.karger.com/pha Gokalp Altun, Trabzon, Turkey Damodaran Annamalai, Portland, USA Hitoshi Ashida, Kobe, Japan Silvia Balosso, Milano, Italy Brandon Banaschewski, London, Canada Chandana C. Barua, Guwahati, India Bonnie L. Bermas, Boston, Mass., USA Babul Kumar Bezbaruah, Guwahati, India Jianping Cai, Beijing, China Dong-Yuan Cao, Xi’an, China Haolin Chen,(More)
Many chemotherapeutic strategies have failed due to pronounced diffusion limitations in tumors induced by poor vasculaturization. Diffusion limitations, present in threedimensional tissue, produce nutrient deficient regions that eventually become necrotic in tumors in vivo. Multicellular spheroids are better models of in vivo tumors than monolayer cultures(More)
This work aims at the development of NARX type nonlinear multivariable stochastic models, which can explicitly account for the dynamics of unmeasured disturbances using input-output data. At the identification stage, the model is arranged to have Weiner like structure and the linear dynamic component of the Weiner model is parameterized using generalized(More)
Background:Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) contains crucial information about tumour heterogeneity and the transport limitations that reduce drug efficacy. Mathematical modelling of drug delivery and cellular responsiveness based on underutilised DCE-MRI data has the unique potential to predict therapeutic responsiveness for(More)
Oxygen availability plays a critical role in cancer progression and is correlated with poor prognosis. Despite this connection, the independent effects of oxygen gradients on tumor tissues have not been measured. To address this, we developed an oxygen delivery device that uses microelectrodes to generate oxygen directly underneath three-dimensional tumor(More)
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