Background: Despite all the advances in medicine and the wide variety of dressings available, the treatment of burn wounds still represents an important medical challenge. The pinus cellulose membrane dressing is a biomaterial with characteristics similar to those of bacterial cellulose, but with lower cost. Aim: To evaluate the efficacy of pinus nanocellulose membrane on healing of deep second degree burns in rats and compare with Membracel®. Method: Thirty male Wistar rats were submitted to deep second degree burn in dorse, with boiling water at 97o C for 20 s, generating a 314 mm² area wound. The animals were distributed in three dressing groups (n=10): group 1 - simple gauze; group 2 - bacterial cellulose membrane (Membracel®); and group 3 - pinus cellulose membrane. They were evaluated for 20 days to verify clinical condition, macro and microscopic appearance and wound contraction. Results: All of them remained clinically well with no differences in weight. Crusts were observed in group 1, and none in groups 2 and 3. Regarding to scar contraction, groups 2 and 3 were similar, better than group 1. Microscopic analysis showed predominance of advanced healing degree in groups 1 and 3, and initial in group 2. Mature collagen was predominant in all groups. Conclusion: The pinus nanocellulose membrane is effective in the treatment of experimental second degree burn in rats and its effectiveness is similar to that of the bacterial nanocellular membrane.
BACKGROUND: Despite the rich vascular arcade of the stomach, gastric ischemia represents an
important medical challenge and can be the consequence of obstructive or
non-obstructive vascular processes of pathological or iatrogenic origin. AIM: To assess the effects of acute gastric ischaemia on the different regions of the
stomach. METHOD: Fifteen New Zeland rabbits were divided into three groups: group 1, animals were
observed during 3 h; group 2, during 6 h; group 3, during 12 h. Rabbit stomachs
were subjected to devascularization of the greater and lesser curvatures. After
predetermined time, the stomachs were removed for macro and microscopic studies.
RESULTS: Haemorrhagic necrosis was more marked in the gastric fundus and body. In
contrast, the antropylorus remained preserved in 80% of the animals. Necrosis of
the gastric body and fundus mucosa were observed in all animals after 6 h and 12 h
of ischaemia. CONCLUSION: Acute gastric ischaemia in rabbits produces haemorrhagic necrosis of the gastric
fundus and body even in a short period of time. Beside this, the antropyloric
region was significantly more resistant to ischaemia.
BackgroundDynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) could provide valuable findings for tendon regeneration. A non-invasive image method that can effectively evaluate the quality of the scar tissue has not yet been employed.MethodsThirteen New Zealand rabbits were divided into two groups: group 1—non-treated control (n = 4); group 2—surgical intervention (n = 9). The central portion of the Achilles tendon was resected, and after 30 days, DCE-MRI was performed. Contrast enhancement methods were applied using the region of interest (ROI) technique. In the medium third of the Achilles tendon, the intra-substantial signal intensity and the presence of hyper-intense intra-tendon focus points and of signal heterogeneity were evaluated. Antero-posterior and transversal diameters of the tendon were measured. The Achilles tendon was removed and dissected free from other tissues. Sections from the central part of the tendon were stained for histological analysis.ResultsThe difference between the contrast enhancement curves of the control and surgical groups (p < 0.0001) was observed. The surgical group had an intense contrast enhancement in the contrast sequences, enlargement of the diameter and intra-substantial signal intensity alteration, with hyper-signal focus points and widening of the tendon sheath, which presented irregular contours and intense contrast enhancement. On histology, the Achilles tendon presented diffuse widening of the tendon sheath and wedge-shaped areas with scarring tissue rich in disordered collagen fibres. These findings were related to alteration in the intra-substantial signal intensity, with hyper-signal focus points in the DCE-MRI.ConclusionsMRI with perfusion could be a useful technique for evaluating tissue and fibrous scarring in tendons.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.