Abstract Introduction: Reperfusion injury leads to systemic morphological and functional pathological alterations. Some techniques are already estabilished to attenuate the damage induced by reperfusion. Ischemic preconditioning is one of the standard procedures. In the last 20 years, several experimental trials demonstrated that the ischemic postconditioning presents similar effectiveness. Recently experimental trials demonstrated that statins could be used as pharmacological preconditioning. Methods: 41 Wistar rats (Rattus norvegicus albinus) were distributed in 5 groups: Ischemia and Reperfusion (A), Ischemic Postconditioning (B), Statin (C), Ischemic Postconditioning + Statins (D) and SHAM (E). After euthanasia, lungs, liver, kidneys and ileum were resected and submitted to histopathological analysis. Results: The average of lung parenchymal injury was A=3.6, B=1.6, C=1.2, D=1.2, E=1 (P=0.0029). The average of liver parenchymal injury was A=3, B=1.5, C=1.2, D=1.2, E = 0 (P<0.0001). The average of renal parenchymal injury was A=4, B=2.44, C=1.22, D=1.11, E=1 (P<0.0001). The average of intestinal parenchymal injury was A=2, B=0.66, C=0, D=0, E=0 (P=0.0006). The results were submitted to statistics applying Kruskal-Wallis test, estabilishing level of significance P<0.05. Conclusion: Groups submitted to ischemic postconditioning, to pre-treatment with statins and both methods associated demonstrated less remote reperfusion injuries, compared to the group submitted to ischemia and reperfusion without protection.

Resumo Neste trabalho, estudou-se em escala piloto a pirólise de três diferentes rejeitos de borracha do setor de mineração, i.e. peças de moinho de composição nominal de borracha estireno e butadieno (SBR), peneiras e correias transportadoras com composição nominal à base de borracha natural e butadieno (NR/BR) e pneus offroad de composição complexa (mistura de borracha natural, nitrílica, butadieno e estireno-butadieno) em temperaturas de 450, 600 e 800°C. As reações realizadas a 450°C mostraram uma pirólise incompleta, sendo que a 600 e 800°C os rejeitos de borracha se convertem totalmente em três produtos: 15-25% de gás, 42-44% sólido e 34-45% de líquido. Análises por cromatografia gasosa (CG) dos produtos gasosos mostraram majoritariamente a presença de hidrocarbonetos C1-C4 com valores de poder calorífico inferior (PCI) iguais a 8.496 e 7.325 kcal kg-1, similares ao gás liquefeito de petróleo (GLP). Análise dos sólidos obtidos por análise elementar de carbono, hidrogênio e nitrogênio (CHN), espectrômetria de emissão atômica com plasma induzido (ICP-AES) Spectro Ciros CCD para a determinação de enxofre, análise térmica gravimétrica e diferencial (TG/DTA), carbono fixo, cinzas, voláteis mostraram a presença de 72-89% de carbono com 2% de enxofre. Análises dos produtos líquidos por cromatografia gasosa acoplado a espectrometria de massas (CG-EM) indicaram a presença de misturas complexas de hidrocarbonetos majoritariamente até C20. As amostras NR/BR e pneu produzem líquidos com concentração de compostos aromáticos próxima a 50%, enquanto a amostra SBR resulta na formação de um líquido de concentração próxima a 87%. A mistura dessa fração líquida obtida pela pirólise (sem qualquer purificação) com um diesel comercial nas proporções de 0,5, 1 e 3 vol% mostrou que nenhum parâmetro de qualidade de combustível definido pela ANP (Agência Nacional do Petróleo, Gás Natural e Biocombustíveis) foi alterado significativamente.

Abstract In this work, the pyrolysis of three different rubber wastes used in the mining industry, i.e. milling (based on styrene butadiene rubber, SBR), sieves and conveyor belts (based on natural and butadiene rubber, NR/BR) and offroad waste tires (based on complex mixture of nitrile, butadiene, styrene and natural rubber) was investigated in a pilot plant at 450, 600 and 800°C. Reactions at 450°C showed incomplete pyrolysis whereas at 600 and 800°C the rubber wastes were completely converted into three products:15-25% gas, 34-45% liquid and 42-44% solids. The gas products analyzed by gas chromatography (GC) showed mainly the presence of C1-C4 hydrocarbons with LHV (Low Heating Value) values between 8496 and 7325 Kcal kg-1, similar to liquefied petroleum gas (LPG). The solid products analyzed by elemental analysis of carbon, hydrogen and nitrogen (CHN), atomic emission spectrometry with inductively coupled plasma (ICP-AES) Spectro Ciros CCD for the determination of sulfur, thermogravimetry and differential thermal analysis (TG/DTA), fixed carbon, ash and volatile compounds showed the presence of 72-89% carbon and 2% sulfur. The liquid products analyzed by gas chromatography applied mass spectrometry (GC-MS) indicated the presence of complex mixtures of hydrocarbons containing mainly compounds up to C20. The NR/BR and waste offroad tire samples produced ca. 50% aromatics whereas SBR rubber resulted in the formation of near 87% aromatics. The mixtures of these liquids products (without any purification) with a commercial diesel fuel at 0.5, 1 and 3 vol% did not significantly change the fuel quality parameters defined by the ANP (Agency National Petroleum, Natural Gas and Biofuels).

PURPOSE: To evaluate wound healing in rats by using low-level laser therapy (LLLT) associated with hydrocolloid occlusive dressing . METHODS: Forty male, adult, Wistar rats were used, distributed into four groups: LG (received 2 J/cm² of laser therapy); HG (treated with hydrocolloid); LHG (treated with 2 J/cm² of laser therapy and hydrocolloid); and the CG (treated with 1 mL of 0.9% saline). The wound was evaluated at pre-determined periods 3rd and 7th days, considering the macroscopic and histological parameters (inflammatory cells, capillary neoformation, fibroblasts, collagen formation and reepithelialization). RESULTS: The LG group at seven days showed increased collagen formation, the LHG group at 3 days showed mild collagen formation. The HG group and the CG at 7 days showed complete reepithelialization. CONCLUSION: Low-level laser therapy as well as the hydrocolloid dressing have favored the wound-healing process in rats.