Characterization of Brazilian Buriti oil biomaterial: the influence on the physical, chemical properties and behaviour of Goat Wharton's jelly mesenchymal stem cells.

The Brazilian Buriti oil presents low extraction costs and relevant antioxidant properties. Thus, this work aimed to analyze Buriti oil biomaterial (BB), within its physicochemical properties, biocompatibility and cellular integration, with the purpose to the use as a growth matrix for Goat Wharton's jelly mesenchymal stem cells. Biomaterials were produced from Buriti oil polymer (Mauritia flexuosa), for it's characterization were performed Infrared Region Spectroscopy (FTIR) and Thermogravimetric Analysis (TG and DTG). The biointegration was analyzed by Scanning Electron Microscopy (SEM) and histological techniques. In order to investigate biocompatibility, MTT (3-(4,5-dimetil-2-tiazolil)-2,5-difenil-2H-tetrazólio) test and hemolytic activity tests were performed. The activation capacity of immune system cellswas measured by phagocytic capacity assay and nitric oxide synthesis . The BB presented an amorphous composition, with high thermal stability and high water expansion capacity, a surface with micro and macropores, and good adhesion of Wharton's jelly mesenchymal stem cells (MSCWJ). We verified the absence of cytotoxicity and hemolytic activity, in addition, BB did not stimulate the activation of macrophages. Proving to be a safe material for direct cultivation and also for manufacturing of compounds used for in vivo applications.

Development of castor polyurethane scaffold (Ricinus communisL.) and its effect with stem cells for bone repair in an osteoporosis model.

The development of 'smart' scaffolds has achieved notoriety among current prospects for bone repair, especially for chronic osteopathy, such as osteoporosis. Millions of individuals in the world suffer from poor bone healing due to osteoporosis. The objective of this work was to produce and characterize castor polyurethane (PU) scaffolds (Ricinus communisL.)andevaluate itsin vitrobiocompatibility with stem cells and osteoinductive effectin vivoon bone failures in a leporid model of osteoporosis. The material was characterized using Fourier-transform infrared spectroscopy, thermogravimetric analysis, SEM, and porosity analysis. Then, the biocompatibility was assessed by adhesion using SEM and cytotoxicity in a 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium assay. The osteoinductive effectin vivowas determined in bone defects in rabbit tibias (Oryctolagus cuniculus) submitted to castor PU scaffold, castor PU scaffold associated with stem cells, and negative control, after four and eight weeks, evaluated by computed microtomography and histopathology. The scaffolds were porous, with an average pore size of 209.5 ± 98.2 µm, absence of cytotoxicity, and positive cell adhesivenessin vitro.All the animals presented osteoporosis, characterized by multifocal osteoblastic inactivity and areas of mild fibrosis. There were no statistical differences between these treatments in the fourth week of treatment. In the eighth week, the treatment with castor PU scaffold alone induced more significant bone formation when compared to the other groups, followed by treatment with an association between castor PU scaffold and stem cells. The castor PU scaffold was harmless to cell culture, favoring cell adhesiveness and proliferation, in addition to inducing bone neoformation in osteoporotic rabbits.

Polyurethane derived from castor oil monoacylglyceride (Ricinus communis) for bone defects reconstruction: characterization and in vivo testing.

Biomaterials used in tissue regeneration processes represent a promising option for the versatility of its physical and chemical characteristics, allowing for assisting or speeding up the repair process stages. This research has characterized a polyurethane produced from castor oil monoacylglyceride (Ricinus communis L) and tested its effect on reconstructing bone defects in rat calvaria, comparing it with commercial castor oil polyurethane. The characterizations of the synthesized polyurethane have been performed by spectroscopy in the infrared region with Fourier transform (FTIR); thermogravimetric analysis (TG/DTG); X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). For the in vivo test, 24 animals have been used, divided into 3 groups: untreated group (UG); control group treated with Poliquil® castor polyurethane (PCP) and another group treated with castor polyurethane from the Federal University of Piauí - UFPI (CPU). Sixteen weeks after surgery, samples of the defects were collected for histological and histomorphometric analysis. FTIR analysis has shown the formation of monoacylglyceride and polyurethane. TG and DTG have indicated thermal stability of around 125 °C. XRD has determined the semi-crystallinity of the material. The polyurethane SEM has shown a smooth morphology with areas of recesses. Histological and histomorphometric analyzes have indicated that neither CPU nor PCP induced a significant inflammatory process, and CPU has shown, statistically, better performance in bone formation. The data obtained shows that CPU can be used in the future for bone reconstruction in the medical field.

Antimicrobial properties of α-Ag2WO4 rod-like microcrystals synthesized by sonochemistry and sonochemistry followed by hydrothermal conventional method.

In this study we report the synthesis of silver tungstate microcrystals (α-Ag2WO4) by sonochemistry method (SC) at 65 °C and sonochemistry followed by conventional hydrothermal (SC + HC) for 1, 6 and 12 h, at 140 °C. The structural characterization by XRD confirms the alpha phase of the orthorhombic structure and the space group Pn2n, for all synthesized microcrystals. All the actives modes identified at the Raman spectroscopy were characteristic of alpha phase. The optical band gap by UV-Vis spectroscopy using the diffuse reflectance were 2.98, 3.0, 2.99 and 2.96 eV, for the microcrystals SC, SC + HC-1 h, SC + HC-6 h and SC + HC-12 h, respectively. FE-SEM images show the rod-like microcrystals, however, exhibiting the plane surface (1 0 1) only for the synthesized microcrystals with the assistance of the hydrothermal method (SC + HC-1 h, SC + HC- 6 h and SC + HC-12 h). The antimicrobial potential was confirmed for all α-Ag2WO4 microcrystals synthesized. However, the SC + HC-12 h microcrystals were more susceptible in the bacterial and fungal inhibition, with MIC values for microorganisms C. albicans, T. rubrum, MRSA e EHEC, 0.2-0.5, 4-9, 250 and 31.25 µg mL-1, respectively.