RAFAEL SIMAS
Projetos de Pesquisa
Unidades Organizacionais
LIM/11 - Laboratório de Cirurgia Cardiovascular e Fisiopatologia da Circulação, Hospital das Clínicas, Faculdade de Medicina
15 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 15
conferenceObject BRAIN DEATH PARADOXICALLY INDUCES LEUCOPENIA AND REDUCTION IN THE NUMBER OF BONE MARROW CELLS(2013) MENEGAT, Laura; BORELLI, Primavera; SIMAS, Rafael; CALIMAN, Julia Maria; SILVA, Luiz Fernando Ferraz; MOREIRA, Luiz Felipe; SANNOMIYA, PaulinaconferenceObject Bilateral Sympathetic Denervation Improves Left Ventricular Function and Prevents Post-Infarction Chamber Remodeling in Rats(2016) ZANONI, F. L.; MOREIRA, L. F.; SIMAS, R.; SILVA, R. G. da; JATENE, F. B.conferenceObject LYMPHOCYTE SUBSETS, EXPRESSION OF ADHESION MOLECULES AND APOPTOSIS IN BONE MARROW CELLS OF BRAIN-DEAD RATS(2015) MENEGAT, Laura; SIMAS, Rafael; ZANONI, Fernando; BORELLI, Primavera; JACYSYN, Jacqueline; MOREIRA, Luiz Felipe; SANNOMIYA, PaulinaconferenceObject Brain death impairs microcirculation with or without autonomic storm: an intravital microscopy study with thoracic epidural anesthesia in rats(2013) SILVA, Isaac Azevedo; SIMAS, Rafael; MENEGAT, Laura; CORREIA, Cristiano de Jesus; FERREIRA, Sueli Gomes; SANNOMIYA, Paulina; MOREIRA, Luiz Felipe PinhoconferenceObject PULMONARY MICROCIRCULATION INTRAVITAL MICROSCOPIC STUDY: THE IMPACT OF BRAIN DEATH INDUCTION IN RATS.(2015) SIMAS, Rafael; ZANONI, Fernando L.; SILVA, Raphael C.; MENEGAT, Laura; SILVA, Isaac A.; SANNOMIYA, Paulina; MOREIRA, Luiz F.- Inhibition of Autonomic Storm by Epidural Anesthesia Does Not Influence Cardiac Inflammatory Response After Brain Death in Rats(2012) SILVA, I. A.; CORREIA, C. J.; SIMAS, R.; CORREIA, C. D. J.; CRUZ, J. W. M. C.; FERREIRA, S. G.; ZANONI, F. L.; MENEGAT, L.; SANNOMIYA, P.; MOREIRA, L. F. P.Background. After brain death (BD) donors usually experience cardiac dysfunction, which is responsible for a considerable number of unused organs. Causes of this cardiac dysfunction are not fully understood. Some authors argue that autonomic storm with severe hemodynamic instability leads to inflammatory activation and myocardial dysfunction. Objectives. To investigate the hypothesis that thoracic epidural anesthesia blocks autonomic storm and improves graft condition by reducing the inflammatory response. Methods. Twenty-eight male Wistar rats (250-350 g) allocated to four groups received saline or bupivacaine via an epidural catheter at various times in relation to brain-death induction. Brain death was induced by a sudden increase in intracranial pressure by rapid inflation of a ballon catheter in the extradural space. Blood gases, electrolytes, and lactate analyses were performed at time zero, and 3 and 6 hours. Blood leukocytes were counted at 0 and 6 hours. After 6 hours of BD, we performed euthanasia to measure vascular adhesion molecule (VCAM)-1, intracellular adhesion molecule (ICAM)-1, interleukin (IL)-1 beta, tumor necrosis factor (TNF)-alpha, Bcl-2 and caspase-3 on cardiac tissue. Results. Thoracic epidural anesthesia was effective to block the autonomic storm with a significant difference in mean arterial pressure between the untreated (saline) and the bupivacaine group before BD (P < .05). However, no significant difference was observed for the expressions of VCAM-1, ICAM-1, TNF-alpha, IL-1 beta, Bcl-2, and caspase-3 (P > .05). Conclusion. Autonomic storm did not seem to be responsible for the inflammatory changes associated with BD; thoracic epidural anesthesia did not modify the expression of inflammatory mediators although it effectively blocked the autonomic storm.
conferenceObject PULMONARY MICROCIRCULATION COMPROMISE AFTER BRAIN-DEAD INDUCTION IN RATS: AN INTRAVITAL MICROSCOPY STUDY(2015) SIMAS, Rafael; ZANONI, Fernando Luiz; MENEGAT, Laura; SANNOMIYA, Paulina; MOREIRA, Luiz FelipeconferenceObject EFFECTS OF HYPERTONIC SALINE SOLUTION ON CARDIAC AND PULMONARY CHANGES AFTER BRAIN DEATH: AN EXPERIMENTAL STUDY(2017) CORREIA, Cristiano; MAGGALHAES, Daniel M.; ZANONI, Fernando; SIMAS, Rafael; SOARES, Rafaela Garcia Ferreira; SILVA, Raphael S. Coutinho E; BREITHAUPT-FALOPPA, Ana Cristina; SANNOMIYA, Paulina; MOREIRA, Luiz Felipe- Hypertonic Saline Modulates Heart Function and Myocardial Inflammatory Alterations in Brain-Dead Rats(2019) MAGALHAES, Daniel Marcelo S.; ZANONI, Fernando Luiz; CORREIA, Cristiano Jesus; SIMAS, Rafael; SOARES, Rafaela Garcia F.; SANNOMIYA, Paulina; MOREIRA, Luiz Felipe P.Background: Brain death (BD) in potential organ donors is responsible for hemodynamic instability and organ hypoperfusion, leading to myocardial dysfunction. Hypertonic saline (HS) is a volume expander with positive effects on hemodynamics and immunomodulation and was tested in this study to prevent left ventricular (LV) dysfunction and myocardial injury. Methods: BD was induced in anesthetized Wistar rats by inflating a subdural balloon catheter, except in sham-operated animals (n = 6). After BD induction, Control animals received only normal saline solution (NaCl 0.9%, 4 mL/kg; n = 6), and treated animals were divided to receive HS (NaCl, 7.5% 4 mL/kg) at 1 min (HS1, n = 6) or 60 min (HS60, n = 6) thereafter. We continuously assessed cardiac function for 6 h with LV pressure-volume analysis. Inflammatory response, markers of myocardial injury, and cellular apoptosis -related proteins were investigated. Results: BD was associated with decreased LV systolic and diastolic function. In comparison with the Control group, HS treatments improved LV ejection fraction (HS1, 51% [40-66]; HS60, 71% [28-82]; Control, 46% [23-55]; P < 0.05) and other parameters of LV systolic function 6 h after BD induction. However, no ventricular relaxation advantages were observed during the same period. HS treatments increased antiapoptotic protein expression and decreased vascular adhesion molecule and tumor necrosis factor alpha expression. No significant differences in histologic or structural protein changes were observed between groups. Conclusions: The observed data suggest that HS ameliorates LV systolic dysfunction and seems to reduce myocardial tissue compromise in BD rats, even when the treatment is performed during the process triggered by this event.
conferenceObject Hypertonic Saline Solution Preserves Left Ventricular Function and Inhibit Myocardial Injury Triggered by Brain Death in Rats(2016) MOREIRA, L. F.; MAGALHAES, D. M.; ZANONI, F. L.; CORREIA, C. J.; SIMAS, R.; SANNOMIYA, P.