Paulo de Tarso Camillo de Carvalho

Analysis of the influence of low-power HeNe laser on the healing of skin wounds in diabetic and non-diabetic rats

PURPOSE To study the influence of HeNe laser irradiation on the collagen percentage in surgically-induced skin wounds in rats with and without alloxan-induced diabetes, by morphometric analysis of collagen fibers. METHODS 48 male Wistar rats were used, divided into groups: laser-treated diabetic (group 1); untreated diabetic (group 2); treated non-diabetic (group 3); and untreated non-diabetic (group 4). For groups 1 and 2, diabetes was induced by intravenous injection of alloxan (2,4,5,6-tetraoxypyrimidine; 5,6-dioxyuracil; Sigma), into the dorsal vein of the penis, at a rate of 0.1 ml of solution per 100 g of body weight. A wound was made on the back of all the animals. Groups 1 and 3 were treated with HeNe laser (4 J/cm2) for 60 s. One animal from each group was sacrificed on the 3rd, 7th and 14th days after wounding. Samples were taken, embedded in paraffin, stained with hematoxylin-eosin and Massons trichrome, and morphometrically analyzed using the Imagelab software. The percentages of collagen fibers were determined from the samples from the euthanasia animals. The data were treated statistically using analysis of variance (ANOVA) and the Student t and Kruskal-Wallis tests. The significance level was set at 0.05 or 5%. RESULTS The results obtained from the samples taken on the third, seventh and fourteenth days after wounding demonstrated that the laser-treated group presented a statistically significant (p<0.05) greater mean quantity of collagen fibers than in the non-treated group, both for diabetic rats (p = 0.0104) and for non-diabetic rats (p = 0.039). CONCLUSION The low-power laser (632.8 nm) was shown to be capable of influencing the collagen percentage in skin wounds by increasing the mean quantity of collagen fibers, both for the diabetic and for the non-diabetic group.

Low-level Laser Therapy Promotes Vascular Endothelial Growth Factor Receptor-1 Expression in Endothelial and Nonendothelial Cells of Mice Gastrocnemius Exposed to Snake Venom

Crotalinae snake venoms cause severe local myonecrosis and microvasculature failure at the bite site. We evaluated whether low‐level laser therapy (LLLT) could accelerate angiogenesis and myoregeneration in male Swiss mice injected with Bothrops moojeni venom through immunohistochemistry of the vascular endothelial growth factor receptor‐1 (VEGFR‐1). Envenomed gastrocnemius was either unirradiated (V) or irradiated with HeNe (VHN, 632.8 nm) or GaAs (VGA, 904 nm, 10000 Hz). Animals sacrificed at 3 and 12 h were irradiated once (4 J cm−2), at 24 h (twice) and at 3, 7, 21 days (4, 8, 22 times, respectively). At 3 days, LLLT increased angiogenesis (80%:HeNe vs 40%:GaAs), decreased neutrophils and increased proliferation of regenerating cells. However, after 21 days, myoregeneration observed in the VHN group appeared delayed compared with the V group. As LLLT improved revascularization, the suggestive delay in myoregeneration could be a dose‐response inhibitory effect caused by multiple irradiations in myogenesis. The immunodetection of VEGFR‐1 in neutrophils, macrophages, satellite cells, fibroblasts, Schwann cells and skeletal and smooth muscle fibers (not seen in saline‐controls) at only the acute stages of envenoming suggests a mediator role for VEGFR‐1 in local alterations. This is the first time that VEGFR‐1 expression, and its modulation by photostimulation, has been demonstrated in endothelial and nonendothelial cells of snake envenomed skeletal muscle.

Histological study of tendon healing in malnourished Wistar rats treated with ultrasound therapy

PURPOSE To investigate the effects of therapeutic ultrasound on the healing of tendon injuries in malnourished rats. METHODS After the intended nutritional states had been attained, the animals (N=36) were distributed into three groups, named: G1(N=12), control group; G2(N=12), malnourished rats treated with 3 MHz ultrasound at an intensity of 0.5 W/cm(2); and G3 (N=12), normal animals treated with 3 MHz at 0.5 W/cm(2). The injuries were induced by means of an operation to expose the heel tendon and crush it using Allis forceps. RESULTS The data obtained relating to leukocyte counts, fibroblasts, vessel neoformation, fibrosis and collagen were subjected to statistical treatment using analysis of variance (ANOVA) and Students t test. Results of p < 0.05 were obtained for fibrosis and collagen. CONCLUSION The ultrasound was shown to be effective in repairing the tendon, even in malnourished animals whose healing process was retarded.

Effect of 650 nm low-power laser on bone morphogenetic protein in bone defects induced in rat femors

PURPOSE To investigate the influence of 650 nm GaAlAs laser on the action of bone morphogenetic protein (BMP) in bone defects produced in rat femurs. METHODS The sample consisted of 12 male albino Wistar rats (Rattus norvegicus). The animals were randomly divided into four experimental groups. After undergoing anesthesia, the fur was removed from the lateral face of the right thigh and surgical dissection was performed to view the femur region. A bone defect was created using a spherical diamond-tipped drill bit. In groups 1 and 2, the defect was filled with a paste of Gen-Tech bone-inducing substance. The animals were treated with GaAlAs laser, at a predetermined dose of joules/cm(2) for 80 seconds, over an area of 1 cm(2). Groups 2 and 4 were used as controls. Bone samples were removed to perform histological procedures and morphometric analyses on the 7th, 14th and 21st days after the operation. The results obtained were subjected to statistical analysis using ANOVA variance according to two criteria, with four repetitions, followed by the post hoc t test. The rejection level for the nullity hypothesis was 0.05 or 5% (alpha < or = 0.05). RESULTS In comparisons between G1, G2, G3 and G4, p = 0.024 was observed. In statistical comparisons using the t test for paired samples, only G1 vs. G4 presented a statistically significant result (p = 0.021). CONCLUSION The association of low-power laser application and Gen-Tech bone-inducing substance achieved a better result than laser application alone or BMP use alone.

Efeitos na medida do ângulo Q com a contração isométrica voluntária máxima do músculo quadricipital

The purpose of this study was to analyze the difference between the angle of the quadriceps in symptomatic and asymptomatic individuals in two different examination situations, having the quadriceps relaxed and in a maximal voluntary isometric contraction (MVIC) through radiographic measurement, aiming to contribute to the assessment and treatment of patients with patelofemoral disorder (PFD). Through the standard radiological method twenty 21 years old mean women (40 knees) were assessed. All individuals were positioned supine using a U-podalic stabilizer, having their lower limbs relaxed, using a plumb film on the anterior tuberosity of the tibia. For the statistical analysis, the averages for the asymptomatic and symptomatic groups in a relaxed and MVIC status, as well as the Student’s t-test with p < 0.05 significance level were used. The mean values to the Q angle compared to the asymptomatic group were 17.15 o on relaxation, and 14.5 o on MVIC, while the asymptomatic group presented 21.45 o , and 15.8 o , respectively. The results in the equality analysis between the symptomatic and asymptomatic groups on the relaxed status attained a p = 0.004, and to the maximal voluntary isometric contraction, p = 0.29. Considering the data attained in the present study, it can be verified that in a relaxing status, there is a difference between the value of the Q angle among symptomatic and asymptomatic individuals, being found a higher value in the FPD bearers, while in a maximal isometric contraction of the quadriceps muscle no statistical difference was found in the present study, with a reduction in the angle in both groups.The purpose of this study was to analyze the difference between the angle of the quadriceps in symptomatic and asymptomatic individuals in two different examination situations, having the quadriceps relaxed and in a maximal voluntary isometric contraction (MVIC) through radiographic measurement, aiming to contribute to the assessment and treatment of patients with patelofemoral disorder (PFD). Through the standard radiological method twenty 21 years old mean women (40 knees) were assessed. All individuals were positioned supine using a U-podalic stabilizer, having their lower limbs relaxed, using a plumb film on the anterior tuberosity of the tibia. For the statistical analysis, the averages for the asymptomatic and symptomatic groups in a relaxed and MVIC status, as well as the Students t-test with p < 0.05 significance level were used. The mean values to the Q angle compared to the asymptomatic group were 17.15o on relaxation, and 14.5o on MVIC, while the asymptomatic group presented 21.45o, and 15.8o, respectively. The results in the equality analysis between the symptomatic and asymptomatic groups on the relaxed status attained a p = 0.004, and to the maximal voluntary isometric contraction, p = 0.29. Considering the data attained in the present study, it can be verified that in a relaxing status, there is a difference between the value of the Q angle among symptomatic and asymptomatic individuals, being found a higher value in the FPD bearers, while in a maximal isometric contraction of the quadriceps muscle no statistical difference was found in the present study, with a reduction in the angle in both groups.

Photodynamic inactivation of in vitro bacterial cultures from pressure ulcers

PURPOSE To evaluate in vitro the antibacterial effect of diode laser light of wavelength 650 nm, in association with the photosensitive substance toluidine blue, on the bacteria in infected skin ulcers. METHODS Samples were collected by means of swabs containing a medium for transporting infected material from skin ulcers. The material was inoculated into culturing medium containing azide blood agar for the growth of Gram-positive bacteria, and MacConkey agar for Gram-negative bacteria, and incubated for 48 hours. The results obtained from counting the colony-forming units were correlated and subjected to statistical analysis, adopting the significance level of p > or = 0.05. RESULTS From analysis of variance (ANOVA), the result for the general mean was p = 0.0215. Using the t test with post-hoc test, the result for TBO vs. Control was p = 0.0186, and for TBO + Laser vs. Control it was p = 0.0039. CONCLUSION There was a significant reduction in colony-forming units when the cultures were subjected to photodynamic therapy.

End-to-side nerve repair using fibrin glue in rats

PURPOSE To evaluate axonal regeneration after end-to-side nerve repair with fibrin glue in rats. METHODS Forty-five Wistar rats were divided into three groups: group A (n=15), were not submitted to surgery (control group); group B (n=15) were submitted to fibular transection without repair; and group C (n=15), were submitted to fibular transection with end-to-side nerve anastomosis using fibrin glue, in the lateral surface of an intact tibial nerve. The three groups were submitted to walking track (30 and 90 days) and posterior morphometrical analysis (90 days). RESULTS The functional tests demonstrated that there was no difference in the walking track during the study in group A (p>0.05). The group B had walking pattern impairment in the two tests (p>0.05). The group C had walking pattern impairment in the first test, with important recovery in the second test (p<0.05). The morphometrical assessment revealed significantly higher number of regenerated mielinates axons in group C, compared to group B (p<0.05). CONCLUSION The end-to-side nerve repair with fibrin glue shows axonal recovery, demonstrated through functional and morphometrical ways in rats.

Experimental model of pulmonary carcinogenesis in Wistar rats

PURPOSE To elaborate an experimental model of pulmonary carcinogenesis in Wistar rats. METHODS Male Rattus norvegicus albinus, Wistar lineage were carried through an intra-pulmonary instillation of the Benzo[a]pyrene (B[a]P) dilution in alcohol 70%, a polycyclic aromatic hydrocarbon widely known by its power of tumoral induction. Three experimental groups had been formed with 08 animals each: Control Group (Alcohol 70%); B[a]P Group 10 mg/kg; e B[a]P Group 20mg/kg, submitted to euthanasia 08, 10, 12 and 14 weeks after the experimental procedure. The pulmonary sections had been colored by hematoxilin-eosin (HE) and submitted to the morphometrical analysis to describe the tissue alterations. RESULTS The presence of diffuse inflammatory alterations was observed in all groups; however, at the analysis of the pulmonary tissue of the experimental groups had been observed hyperplasic alterations (BALT hyperplasia), and in one of the animals of the experimental group 20mg/kg (12 weeks) was noticed the presence of cellular epithelial tracheal pleomorphism, suggesting the adenocarcinoma formation in situ. CONCLUSION The main secondary alterations to the intra-pulmonary instillation of B[a]P in Wistar rats were: cellular proliferation, inflammatory alterations of several degrees and nodular lymphoid hyperplasias. The association of an activator agent of the pulmonary metabolic reply is necessary to establish the ideal reply-dose to the development of the lung cancer.

Efeito de diferentes tempos de alongamento na flexibilidade da musculatura posterior da coxa

O alongamento e uma das tecnicas mais utilizadas para se obter aumento da amplitude de movimento (ADM), porem nao ha consenso sobre o tempo necessario de alongamento para aumentar a flexibilidade. O objetivo do estudo foi verificar qual tempo de duracao de alongamento e mais eficaz, avaliando-se a flexibilidade pela mensuracao do ângulo popliteo (AP). Foram recrutadas 30 voluntarias com idade media de 21,1±2,9 anos, divididas aleatoriamente em cinco grupos (controle, 15, 60, 90 e 120 segundos), e submetidas a quatro semanas de alongamento passivo durante diferentes tempos, sendo avaliadas por tres examinadores clinicos pelo teste do AP associado a ADM. Os dados foram submetidos a analise estatistica, com nivel de significância p<0,05; para verificar a confiabilidade inter-examinadores foi utilizado o coeficiente de correlacao intraclasse (ICC); a confiabilidade foi excelente (ICC=0,985). Houve diferenca significativa quando se compararam 15 segundos de alongamento com 120 segundos (p<0,01) e tambem na comparacao entre os grupos de 90 e 120 segundos (p<0,05). O ganho de ADM foi maior nos grupos 90 e 120 segundos. O grupo de 120 segundos apresentou a maior media e o de 90 segundos, a maior variacao no quesito confiabilidade entre examinadores. Conclui-se que quanto maior o tempo de sustentacao do alongamento, maior sera o ganho de flexibilidade.

Usefulness of argyrophilic nucleolar organizer regions in detection of lung cells alterations after benzo[a]pyrene instillation

PURPOSE To verify the relationship between AgNOR expression and lung tissues changes of Wistar rats after pulmonary instillation of benzo[a]pyrene (B[a]P). METHODS Male Rattus norvegicus albinus,Wistar lineage were given a single intrapulmonary instillation of B[a]P at doses of 10 and 20 mg/kg in a volume of approximately 0.3 ml. After 7 and 21 days the rats were killed and the lung slices submitted to a histological technique of AgNOR. AgNOR dots were quantified and the result analyzed by statistical tests; p < or = 0.05 was considered significant. RESULTS The mean values of AgNOR dots for the experimental groups 10/7 (1.51+/-0.86) and 10/21 (1.84+/-0.13) were statistically different (p = 0.009). Among the groups 20/7 (1.63+/-0.11) and 20/21 (2.48+/-0.28) was observed statistically significant difference (p = 0.003). CONCLUSION The AgNOR technique can be useful in identification of cells changes induced by B[a]P.