Tissue-scale, personalized modeling and simulation of prostate cancer growth

Recently, mathematical modeling and simulation of diseases and their treatments have enabled the prediction of clinical outcomes and the design of optimal therapies on a personalized (i.e., patient-specific) basis. This new trend in medical research has been termed “predictive medicine.” Prostate cancer (PCa) is a major health problem and an ideal candidate to explore tissue-scale, personalized modeling of cancer growth for two main reasons: First, it is a small organ, and, second, tumor growth can be estimated by measuring serum prostate-specific antigen (PSA, a PCa biomarker in blood), which may enable in vivo validation. In this paper, we present a simple continuous model that reproduces the growth patterns of PCa. We use the phase-field method to account for the transformation of healthy cells to cancer cells and use diffusion-reaction equations to compute nutrient consumption and PSA production. To accurately and efficiently compute tumor growth, our simulations leverage isogeometric analysis (IGA). Our model is shown to reproduce a known shape instability from a spheroidal pattern to fingered growth. Results of our computations indicate that such shift is a tumor response to escape starvation, hypoxia, and, eventually, necrosis. Thus, branching enables the tumor to minimize the distance from inner cells to external nutrients, contributing to cancer survival and further development. We have also used our model to perform tissue-scale, personalized simulation of a PCa patient, based on prostatic anatomy extracted from computed tomography images. This simulation shows tumor progression similar to that seen in clinical practice.Peer ReviewedPostprint (published version

Análise do efeito da fluorescência produzida em amostra de gasolina com observação dos espectros Raman utilizando LPA2v e PCA / Analysis of the effect of fluorescence produced in a gasoline sample with observation of Raman spectra using LPA2v and PCA

O trabalho se propõe a avaliar o efeito do ruído de fluorescência (ruído de fóton ou shot noise) na classificação dos espectros de amostras de gasolinas padrão e adulteradas obtidas em postos de combustíveis na região de Santos/SP. Foram obtidas 15 amostras de diferentes postos de abastecimento, sendo 5 amostras padrão e 10 contendo algum tipo de adulteração (maior concentração de etanol ou presença de solvente orgânico). As técnicas de Lógica Paraconsistente Anotada com anotação de dois valores (LPA2v) e a análise de componente principal (PCA) com análise discriminante foram empregadas buscando-se verificar até que ponto a influência de diferentes níveis de ruído de fluorescência impactaria a classificação das amostras. Os resultados demonstraram que o ruído de fluorescência impacta a classificação das amostras, onde menores níveis de ruído (até 100 contagens) foram classificados corretamente pela LPA2v, enquanto que maiores níveis de ruído (200 contagens) promoveram melhor classificação para a técnica PCA

Location of chlorogenic acid biosynthesis pathway and polyphenol oxidase genes in a new interspecific anchored linkage map of eggplant

© Gramazio et al.; licensee BioMed Central. 2014. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated

Background Light in Potential Sites for the ANTARES Undersea Neutrino Telescope

The ANTARES collaboration has performed a series of {\em in situ} measurements to study the background light for a planned undersea neutrino telescope. Such background can be caused by $^{40}$K decays or by biological activity. We report on measurements at two sites in the Mediterranean Sea at depths of 2400~m and 2700~m, respectively. Three photomultiplier tubes were used to measure single counting rates and coincidence rates for pairs of tubes at various distances. The background rate is seen to consist of three components: a constant rate due to $^{40}$K decays, a continuum rate that varies on a time scale of several hours simultaneously over distances up to at least 40~m, and random bursts a few seconds long that are only correlated in time over distances of the order of a meter. A trigger requiring coincidences between nearby photomultiplier tubes should reduce the trigger rate for a neutrino telescope to a manageable level with only a small loss in efficiency.Comment: 18 pages, 8 figures, accepted for publication in Astroparticle Physic