Effect of vaporized perfluorocarbon on oxidative stress during the cold ischemia phase of lung graft preservation.

Liquid perfluorocarbon (PFC) instillation has been studied experimentally as an adjuvant therapy in the preservation of lung grafts during cold ischemia. The objective of this study was to evaluate whether vaporized PFC is also protective of lung grafts at different cold ischemia times. We performed histological analysis of and measured oxidative stress in the lungs of animals that received only preservation solution with low-potassium dextran (LPD) or vaporized PFC together with LPD. We conclude that vaporized PFC reduces the production of free radicals and the number of pulmonary structural changes resulting from cold ischemia.

Effect of vaporized perfluorocarbon on oxidative stress during the cold ischemia phase of lung graft preservation / Efeito do perfluorocarbono vaporizado sobre o estresse oxidativo no período de isquemia fria durante a preservação pulmonar

ABSTRACT Liquid perfluorocarbon (PFC) instillation has been studied experimentally as an adjuvant therapy in the preservation of lung grafts during cold ischemia. The objective of this study was to evaluate whether vaporized PFC is also protective of lung grafts at different cold ischemia times. We performed histological analysis of and measured oxidative stress in the lungs of animals that received only preservation solution with low-potassium dextran (LPD) or vaporized PFC together with LPD. We conclude that vaporized PFC reduces the production of free radicals and the number of pulmonary structural changes resulting from cold ischemia.

RESUMO O perfluorocarbono (PFC) líquido tem sido estudado experimentalmente como uma substância adjuvante na preservação de enxertos pulmonares durante o período de isquemia fria. O objetivo deste estudo foi avaliar se o PFC vaporizado (e não instilado) também atuaria como protetor de enxertos pulmonares em diferentes tempos de isquemia fria. Realizamos análise histológica e dosamos o estresse oxidativo em pulmões de animais que receberam somente uma solução de preservação com low-potassium dextran (LPD, dextrana com baixa concentração de potássio) ou PFC vaporizado associado a LPD. Concluímos que o PFC vaporizado reduziu a produção de radicais livres e provocou menor número de alterações estruturais pulmonares decorrentes do período de isquemia fria que o uso de LPD isoladamente.

Technique for implanting intramuscular electrodes in the diaphragm by videolaparoscopy in pigs.

PURPOSE: To describe a novel approach for implanting intramuscular electrodes in the diaphragm through videolaparoscopy. METHODS: We used twelve pigs for this videolaparoscopic technique, which permits at the same time to explore the diaphragm, to locate its motor points and to fix the electrodes in the diaphragm bilaterally. In this technique we used three trocars: one portal for a 10-mm 0° viewing angle laparoscope, one portal for the manipulation of structures and another for electrode implantation. RESULTS: All animals survived the procedure without pneumothorax/capnothorax or other complication. Implanted electrodes provided an appropriate interface between the muscle and the electrical current generator, and electroventilation was satisfactorily generated in all animals. CONCLUSION: This videolaparoscopic technique with three trocars enables the exploration and identification of motor points and an efficient fixation of one or two electrodes in each hemidiaphragm.

Technique for implanting intramuscular electrodes in the diaphragm by videolaparoscopy in pigs

PURPOSE: To describe a novel approach for implanting intramuscular electrodes in the diaphragm through videolaparoscopy. METHODS: We used twelve pigs for this videolaparoscopic technique, which permits at the same time to explore the diaphragm, to locate its motor points and to fix the electrodes in the diaphragm bilaterally. In this technique we used three trocars: one portal for a 10-mm 0° viewing angle laparoscope, one portal for the manipulation of structures and another for electrode implantation. RESULTS: All animals survived the procedure without pneumothorax/capnothorax or other complication. Implanted electrodes provided an appropriate interface between the muscle and the electrical current generator, and electroventilation was satisfactorily generated in all animals. CONCLUSION: This videolaparoscopic technique with three trocars enables the exploration and identification of motor points and an efficient fixation of one or two electrodes in each hemidiaphragm.

RC-3095, a selective gastrin-releasing peptide receptor antagonist, does not protect the lungs in an experimental model of lung ischemia-reperfusion injury.

RC-3095, a selective GRPR antagonist, has been shown to have anti-inflammatory properties in different models of inflammation. However, its protective effect on lungs submitted to lung ischemia-reperfusion injury has not been addressed before. Then, we administrated RC-3095 intravenously before and after lung reperfusion using an animal model of lung ischemia-reperfusion injury (LIRI) by clamping the pulmonary hilum. Twenty Wistar rats were subjected to an experimental model in four groups: SHAM, ischemia-reperfusion (IR), RC-Pre, and RC-Post. The final mean arterial pressure significantly decreased in IR and RC-Pre compared to their values before reperfusion (P < 0.001). The RC-Post group showed significant decrease of partial pressure of arterial oxygen at the end of the observation when compared to baseline (P = 0.005). Caspase-9 activity was significantly higher in the RC-Post as compared to the other groups (P < 0.013). No significant differences were observed in eNOS activity among the groups. The groups RC-Pre and RC-Post did not show any significant decrease in IL-1ß (P = 0.159) and TNF-α (P = 0.260), as compared to IR. The histological score showed no significant differences among the groups. In conclusion, RC-3095 does not demonstrate a protective effect in our LIRI model. Additionally, its use after reperfusion seems to potentiate cell damage, stimulating apoptosis.