Edvaldo Lima Silveira

Histological analysis of low-intensity laser therapy effects in peripheral nerve regeneration in Wistar rats

PURPOSE Analyze the influence of low-intensity laser therapy in the sciatic nerve regeneration of rats submitted to controlled crush through histological analysis. METHODS Were used 20 Wistar rats, to analyze the influence of low-intensity laser therapy in the sciatic nerve regeneration, where the injury of the type axonotmesis was induced by a haemostatic clamp Crile (2nd level of the rack). The animals were randomly distributed in 2 groups. Control group (CG n = 10) and Laser group (LG n = 10). These were subdivided in 2 subgroups each, according to the euthanasia period: (CG14 - n = 5 and CG21 - n = 5) and (LG14 - n = 5 and LG21 - n = 5). At the end of treatment, the samples were removed and prepared for histological analysis, where were analyzed and quantified the following findings: Schwann cells, myelinic axons with large diameter and neurons. RESULTS In the groups submitted to low-intensity laser therapy, were observed an increase in the number of all analyzed aspects with significance level. CONCLUSION The irradiation with low intensity laser (904nm) influenced positively the regeneration of the sciatic nerve in Wistar rats after being injured by crush (axonotmesis), becoming the nerve recovery more rapid and efficient.

Effect of copaiba oil on correction of abdominal wall defect treated with the use of polypropylene/polyglecaprone mesh

PURPOSE To evaluate the effects of copaiba oil on the correction of abdominal defect treated with the use of polypropylene/polyglecaprone mesh in rats. METHODS A defect in the abdominal wall was created and corrected with polypropylene/polyglecaprone mesh in 36 rats. They were randomly distributed into three groups: control, copaiba by oral administration (gavage) and copaiba oil dip in the mesh. Euthanasia was performed after seven, 14 and 21 post-operative days. The healing process was analyzed regarding the meshes and macroscopic and microscopic aspects. RESULTS All animals had abdominal adhesions, which were smaller in the copaiba (gavage) group (p<0.05). In microscopy, all animals had an acute inflammation stage and the inflammatory response was best characterized by foreign body-type granulomas around the mesh fragments, which was not found in the mesh fragments within the copaiba dip group. There was a greater area of necrosis and fibrosis in the copaiba dip group compared to the control group (p<0.05). The copaiba (gavage) group had a greater quantity of collagen fibers compared to the control group. CONCLUSION Copaiba oil administered by gavage decreased the amount of abdominal adhesions, besides accelerating the process of collagen fibers formation, without damages within the early stages of healing. However, when used by dip directly on the mesh, it had corrosive effects compromising the healing process of the abdominal wall.

New immunologic pathways in the pathogenesis of leprosy: Role for Th22 cytokines in the polar forms of the disease

To the Editor: Leprosy is an infectious disease caused by Mycobacterium leprae with clinical manifestations that are vastly dependent on the host’s immune response. The role of Th22 cells in the immunopathogenicity of leprosy has yet to be characterized. Thirty-one untreated adults, 19 women and 12 men, were selected for evaluation from the Brazilian state of Para with positive leprosy diagnoses according to World Health Organization and Ridley-Jopling system criteria. Sixteen were defined as tuberculoid and 15 as lepromatous. The study was approved by the Ethics Committee of the Federal do Para University (number 212.969). For immunohistochemical analysis, tissue biopsies were immunostained with monoclonal antibodies against IL-23, IL-22, TNF, and FGFb (fibroblast growth factor basic) (Fig 1). A quantitative analysis was made by randomly selecting 5 visual fields (3400 magnification; 0.0625 mm) using a 10 3 10 reticulated grid. Mann-Whitney and Pearson’s correlation tests were used for univariate analyses with P # .05 considered to be statistically significant. Quantitative analysis revealed a significant difference in IL-22 levels in tissues from patients with polar forms of leprosy (TT 1⁄4 90.39 6 30.18; LL 1⁄4 241.3 6 44.63; P# .0001), with higher levels observed in the lepromatous form with intense staining in vacuoles and globules of infected macrophages. Our results corroborate these observations, in that inactivation of the macrophage lytic response is largely responsible for the increased bacterial dissemination and evasive capacity of M leprae. Therefore, IL-22 expression presents as a possible alternative mechanism for triggering phagolysosomal maturation. In particular, IL-22 can stimulate the expression of

Aspectos microscópicos do fígado de ratos após administração do óleo de copaíba

The use of medicinal plants is a commonly practice observed at developing countries. Then, this paper aim to verify the effect of the copaiba oil in the liver of rats. Fifty male Wistar rats were used distributed into five groups: Group Copaiba 0.63 (GC0.63 ml/kg of copaiba oil), Group Copaiba 0.06 (GC0.06 ml/kg of copaiba oil), Group Water (GA0.63 ml/kg of water), Group Corn Oil (GM0.63 ml/kg of corn oil) and Standard group (GP). The substances were administered daily by 14 days. The animals were submitted to euthanasia in the 14th day, being withdraw the liver and realized histologic study. The results demonstrated that microscopically, in the hepatocity cells no alterations were found; however, vascular congestion was verified in the portal and mid-lobular veins. A larger congestion was observed in the group GC0.63 in relation to the groups GC0.06, GM, GA and GP (p 0.05), suggesting a dose-effect relationship. Then, the authors conclude that in agreement with methodology used, the copaiba oil promote vascular congestion in the liver of rats, suggesting dose-dependent action.

Copaiba oil effect under different pathways in mice subjected to sepsis.

PURPOSE To evaluate the effects of copaiba oil administered by different routes on survival of mices subjected to cecal ligation and puncture. METHODS Thirty two mice were distributed into four study groups (N=8): Sham group: normal standard animals; CONTROL GROUP submitted a cecal ligation and puncture (CLP); Gavage group: submitted a CLP, and treat with copaiba oil by gavage; and Subcutaneous group: submitted a CLP, and treat with copaiba oil by subcutaneous injection. After the death of the histological analysis were performed. The Kaplan-Meier curves of surviving time were realized. RESULTS All animals that received copaiba, regardless of the route used, survived longer when compared to the control group (p<0.0001), whereas the survival time ranged from 20 hours for the control group up to 32 hours for the animals of gavage group and 52 for subcutaneous group. The animals that received gavage copaiba lived about and about 20 hours unless the subcutaneous group (p=0.0042). There was no statistical difference when compared the intensity of inflammatory response (p>0.05) CONCLUSION: Prophylactic subcutaneous administration of copaiba in mice subjected to severe sepsis by cecal ligation and puncture, resulted in a survival time higher than non-use or use of this oil by gavage.

Do the femoral veins of female Wistar rats have valves

The femoral veins of 30 female rats of the Wistar lineage were studied using histological methods with the objective of determining whether they have valves. Histological analysis did not detect any endothelial projections or valve recesses that would suggest the presence of venous valves in this species of animal.

New experimental model of exposure to environmental tobacco smoke

PURPOSE To describe a new model to passive smoking for rodents. METHODS Twenty rats were distributed into two study groups (N=10): control group (CG), that was not exposed to tobacco smoke and used as normal standard for biochemical and histological analysis; Experimental Group (EG), that Animals were exposed to the passive smoking; Euthanasia was performed after 14 days of exposure. The serum level of nicotine and histological analysis were performed. RESULTS There was a statistical difference on the nicotine serum levels between Experimental and Control group, with level of 286 ± 23 nanograma/mL in the EG and undetectable on CG (p<0.01). The histological study suggested the model efficacy producing alveolar destruction and emphysema in the EG compared with the insignificant lesions in the CGs lung. CONCLUSION The model of exposure to environmental tobacco smoke for rodents induced easily the changes related to secondhand smoke.