Marcelo Zoccoler

• Doctor of Engineering
• State University of Campinas (UNICAMP)

Motivation A reliable characterization of the membrane pore edge tension of single giant unilamellar vesicles (GUVs) requires the measurement of micrometer sized pores in hundreds to thousands of images. When manually performed, this procedure has shown to be extremely time-consuming and to generate inconsistent results among different users and im...

Background: In cell biology, increasing focus has been directed to fast events at subcellular space with the advent of fluorescent probes. As an example, voltage sensitive dyes (VSD) have been used to measure membrane potentials. Yet, even the most recently developed genetically encoded voltage sensors have demanded exhausting signal averaging thr...

Multidirectional defibrillation protocols have shown better efficiency than monodirectional; still, no testing was performed to assess cell lethality. We investigated lethality of multidirectional defibrillator-like shocks on isolated cardiomyocytes. Cells were isolated from adult male Wistar rats and plated into a perfusion chamber. Electrical fie...

The mechanisms of excitation-contraction coupling in the heart can be studied through isolated cardiomyocytes shortening. One way to measure shortening is by cell image edge detection. We developed a software that displays and acquires the shortening signal by edge detection. The software was capable of properly measuring contraction in isolated ca...

Although high-intensity electric fields (HEF) application is currently the only effective therapy available to terminate ventricular fibrillation, it may cause injury to cardiac cells. In this study we determined the relation between HEF pulse length and cardiomyocyte lethal injury. We obtained lethality curves by survival analysis, which were used...

The defibrillation is the only effective therapy against ventricular fibrillation. Although a common clinical procedure, this technique also harms healthy cells by means of electroporation, possibly re-introducing arrhythmias. In order to study how myocytes respond to high electric fields (E), scientists commonly use fluorescent dyes in sophisticat...

Microtubules (MTs) are dynamic cytoskeletal elements involved in numerous cellular processes. While they are highly rigid polymers with a persistence length of 1-8 mm, they may exhibit curved shape at a scale of few micrometers within cells depending on their biological functions. However, how MT flexural rigidity in cells is regulated remains poor...