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Biology subjects

Oliveira, J. M.

Publications and source records attributed to Oliveira, J. M..

2 recordsLinked to original sources

Acute exposure of fruit bats to low concentrations of heavy metals affects oxidative stress markers

Cadmium (Cd), chromium (Cr), lead (Pb), and nickel (Ni) are heavy metals and common environmental pollutants. We aimed to investigate heavy metals effects on fruit-bats organs. Adult males (Artibeus lituratus) were captured and exposed to heavy metals (1.5 mg/kg). The Integrated Biomarker Response helped us understand the interrelationship in a multi-biomarker global approach to oxidative stress. The liver was more sensitive to Ni and Pb than Cd and Cr. In the kidney, Pb did not cause hazardous effects, unlike the other metals. In testes, Ni doubled damage levels compared to the other metals. Ni did not cause serious effects in muscles, which was more sensitive to Pb and Cd than to Cr. The brain was more susceptible to Pb and Ni than Cr and Cd. We observed that acute doses, even in low concentrations, are deleterious to fruit-bats. We propose the following order of metal toxicity: Ni> Pb> Cd> Cr. SUMMARY STATEMENTThe investigation of heavy metals toxicity in fruit bats reveals differential sensitivities of organ and highlights the harmful effects of acute exhibitions even at low concentrations.

pharmacology and toxicology↗

Combining experiments and in silico modeling to infer the role of adhesion and proliferation on the collective dynamics of cells

The collective dynamics of cells on surfaces and interfaces poses technological and theoretical challenges in the study of morphogenesis, tissue engineering, and cancer. Different mechanisms are at play, including, cell-cell adhesion, cell motility, and proliferation. However, the relative importance of each one is elusive. Here, experiments with a culture of glioblastoma multiforme cells on a substrate are combined with in silico modeling to infer the rate of each mechanism. By parametrizing these rates, the time-dependence of the spatial correlation observed experimentally is reproduced. The obtained results suggest a reduction in cell-cell adhesion with the density of cells. The reason for such reduction and possible implications for the collective dynamics of cancer cells are discussed.

cell biology↗