Membrane Group Research Articles

Therapeutic Potential of TRPM Modulator

Transient Receptor Potential (TRP) channels are group of membrane proteins that play a key role in managing variety...

Photobiomodulation and bacterial cellulose membrane in the treatment of third-degree burns in rats

Burns are injuries caused mainly by thermal trauma, which can progress to unsatisfactory results healing. This study aimed to evaluate the biomaterial (bacterial cellulose membrane) and photobiomodulation, exclusively and associated, in the treatment of third degree burns in rats. Forty male Wistar rats (±280 g) were randomly divided into four groups, with 10 animals each: control group (CG); bacterial cellulose membrane group (MG); laser group (LG) and bacterial cellulose membrane and laser group (MG + L). The burn was caused with a 1 cm2 aluminum plate heated to 150 °C and pressed on the animal's back for 10 s. The treatments were started immediately after induction of injury. For to laser irradiation (660 nm, 100 mW, 25 J/cm2 and energy of 1 J) on five distinct application points were used, on alternate days, a total of five sessions. After ten days of treatment the animals were euthanized for collected samples. One-way ANOVA and Tukey's tests (P < 0.05) were used. Histological analysis revealed differences regarding the healing process phase in each experimental group. MG showed the proliferative phase. The LG demonstrated greater amount of blood vessels and immune expression of VEGF. However, when the treatments were combined, the number of vessels and the immune expression of VEGF factor was lower than LG. Thus, it was concluded that both treatments proposed (biomaterial and LLLT) are good alternatives for third degree burns when applied isolated because they stimulate the healing process by acting on the modulation of the inflammatory phase and promote stimulation of angiogenesis.

Bacterial cellulose membrane used as biological dressings on third-degree burns in rats.

Burn injuries represent a high risk of morbidity and mortality. The wound healing process is complex and requires the participation of different types of cells. Therefore, new biomaterials, which innovate the wound healing process, are being investigated. The aim of this study was to investigate the use of bacterial cellulose both in its pure state and enriched with lidocaine in full-thickness burns in rats. Thirty rats (Wistar) (260± 20gramas) divided into control group (CG), bacterial cellulose membrane group (MG) and bacterial cellulose membrane enriched with lidocaine group (MLG) were used. The burns were induced using a 150°C heated soldering iron, held on the animal neck for 10seconds. The biomaterial was applied immediately after injury and skin samples were collected on the tenth day of the treatment. The level of significance of p⩽0.05 was used for the conclusion of the statistical analysis. The groups treated with the biomaterials, a histological pattern compatible with a more advanced repair stage showing skin appendages, mild inflammatory infiltrate, better collagen fiber organization and mild immunostaining COX-2 and MMP-9 was observed, when compared to the control group that did not receive any type of treatment. Thus, was concluded that the bacterial cellulose-based biomaterial both in its pure state and enriched with lidocaine optimizing the full-thickness burn wound healing in rats.

Immunolocalization of bone morphogenetic protein 2 during the early healing events after guided bone regeneration

The objective of this study was to evaluate the immunolocalization of bone morphogenetic protein 2 (BMP-2) after autogenous block grafting covered or not with an e-PTFE membrane. Forty-eight rats were divided into 2 groups, autogenous block graft (B) and autogenous block graft + e-PTFE membrane (MB), and were evaluated by immunohistochemistry at baseline and 3, 7, 14, 21, and 45 days. The largest number of positive cells in the recipient bed was observed after 3 days in both groups. At the graft border, the largest number of positive cells was seen after 7 days in group B and after 14 days in group MB. The highest proportion of staining in the graft was observed after 3 days in group B and after 21 days in group MB. High proportions of stain were related to intense revascularization and osteogenesis. Except for the interface, BMP-2 staining occurred later in group MB than in group B in all structures analyzed.

Early healing pattern of autogenous bone grafts with and without e-PTFE membranes: A histomorphometric study in rats

The aim of this study was to perform quantitative and qualitative analyses of the initial repair pattern of an autogenous bone block graft when covered or not with e-PTFE membranes. Sixty male Wistar rats received a bone graft plus an e-PTFE membrane (MB) or just the graft (B). A block graft was harvested from the animal's calvarium and was laid and stabilized on the external cortical area near the angle of the mandible. Descriptive histology and histomorphometric analyses were carried out and the data were analyzed statistically by ANOVA and the Tukey test, with the level of significance set at 5%. The results for group B showed that there was bone loss during the healing period (B0 = 1.38, B45 = 1.05, F = 7.91 > F(C) = 3.02), that is, the initial volume of the graft decreased in time. Bone tissue loss was about 24%. In contrast, the MB group showed bone tissue gain along the observation period (MB0 = 1.54, MB45 = 2.40, F = 7.91 > F(C) = 3.02), meaning that the total volume of newly formed bone was greater than the original graft area. Bone tissue gain was approximately 55%. MB showed significantly greater bone gain when compared to B (B45 = 1.05, MB45 = 2.40, F = 39.86 > F(C) = 1.90). These significant differences between B and MB could already be observed after 21 days. The bone block graft underwent resorption at an early healing stage, while additional new bone formation was observed when the bone graft was covered with an e-PTFE membrane.