Dosimetry of a Carbon Dioxide Laser for Black Tattoo Removal in a Rat Model.

Objective: To determine the optimal parameters of power, energy, and time for the application of a carbon dioxide laser for Tribal Black ink tattoo removal. Background data: The use of antiquated techniques to remove tattoos demonstrates the difficulty of making advances in this field. Studies by the American Society for Dermatologic Surgery have shown that 5% of the global population has at least one tattoo on the body, with 10% of them wanting a tattoo to be removed. Laser removal has been studied and improved as a less invasive and safer method of surgical removal; however, the ideal dosimetry is not yet established. Materials and methods: Thirty-three male Wistar rats were anesthetized and tattooed in the dorsal region in a quadrangular manner. The rats were distributed under low/null luminosity for 4 months into three equal and random groups for the application of the laser, namely, G1 (P = 0.6 W, Et = 0.9 J), G2 (P = 0.8 W, Et = 1, 2 J), and G3 (P = 1 W, Et = 1.5 J), with the application time standardized to 0.15 sec with 10 passes per application. The procedure was repeated at intervals of 4 weeks until 10 cycles of laser application were completed. The images were studied using the ImageJ program and histological analysis and subjected to the one-way ANOVA test for Tukey's multiple comparison post-test. Results: We observed a significant difference between groups 1 and 3 and between groups 2 and 3. Conclusions: The laser with the parameters of P = 1 W, Et = 1.5 J, and t = 0.15 sec yields better Tribal Black ink removal results.

Influence of low-level laser irradiation on osteocalcin protein and gene expression in bone tissue1.

PURPOSE: To evaluate osteocalcin gene and protein expression in vitro and in an in vivo model of ostectomy. METHODS: Twenty Wistar rats were assigned into two groups A (n=10, laser) and B (n=10, control). Ostectomy was performed in the femur diaphysis; the twenty fragments removed, composed in vitro groups named as in vivo (A and B) and cultivated in CO2 atmosphere for thirteen days. Low-level laser irradiation was performed in groups A (in vivo and in vitro) by an GaAlAs device (λ=808 nm, dose of 2J/cm2, power of 200mW, power density of 0.2W/cm2, total energy of 1.25J, spot diameter of 0.02mm) for 5 seconds, at one point, daily. It was performed immunocytochemistry assays in vivo and in vitro groups. In vitro groups were also submitted to RNA extraction, cDNA synthesis and gene expression by quantitative PCR. Statistical analysis was realized with p<0.05. RESULTS: Immunocytochemistry scores showed no significant differences between control and laser groups either in vivo and in vitro. Gene expression also showed no statistical differences. CONCLUSION: Low-level laser irradiation did not alter osteocalcin protein and gene expression in vivo and in vitro in the studied period but it may have been expressed them in an earlier period.

Influence of low-level laser irradiation on osteocalcin protein and gene expression in bone tissue1

Abstract Purpose: To evaluate osteocalcin gene and protein expression in vitro and in an in vivo model of ostectomy. Methods: Twenty Wistar rats were assigned into two groups A (n=10, laser) and B (n=10, control). Ostectomy was performed in the femur diaphysis; the twenty fragments removed, composed in vitro groups named as in vivo (A and B) and cultivated in CO2 atmosphere for thirteen days. Low-level laser irradiation was performed in groups A (in vivo and in vitro) by an GaAlAs device (λ=808 nm, dose of 2J/cm2, power of 200mW, power density of 0.2W/cm2, total energy of 1.25J, spot diameter of 0.02mm) for 5 seconds, at one point, daily. It was performed immunocytochemistry assays in vivo and in vitro groups. In vitro groups were also submitted to RNA extraction, cDNA synthesis and gene expression by quantitative PCR. Statistical analysis was realized with p<0.05. Results: Immunocytochemistry scores showed no significant differences between control and laser groups either in vivo and in vitro. Gene expression also showed no statistical differences. Conclusion: Low-level laser irradiation did not alter osteocalcin protein and gene expression in vivo and in vitro in the studied period but it may have been expressed them in an earlier period.

Effect of low-level laser therapy on bone repair: a randomized controlled experimental study.

The aim of this study was to investigate the effect of low-level laser therapy (LLLT) on bone repair in femoral fractures. Sixty adult Wistar rats were randomly assigned into one of two groups: group A (ostectomy + LLLT) or group B (ostectomy + sham laser). An experimental model of complete bone fracture was surgically created by removing a 2-mm fragment from the middle third of the femoral shaft. Data were analyzed on days 8, 13, and 18 after the fracture (subgroups 1, 2, and 3). Samples were assessed for changes in inflammatory infiltration; trabecular bone matrix, periosteal, and new bone formations; and changes in the expression of particular osteogenic-related proteins (osteocalcin, osteopontin, and osteonectin). Microscopic analysis revealed a significant decrease in inflammatory infiltration, intense trabecular bone matrix and periosteal formation, and an increase in newly formed bone after laser irradiation. We also found an increase in the expression of bone matrix proteins with LLLT, with a significant difference measured for osteocalcin in the LLLT group at day 8 (p = 0.007). We show that LLLT plays an important role in augmenting bone tissue formation, which is relevant to fracture healing. LLLT may therefore be indicated as an adjunct therapeutic tool in clinical practice for the treatment or recovery of nonunion injuries.

Análise eletromiográfica de músculos do quadril em diferentes tipos de apoio monopodálico / Electromyography assessment of hip muscles in different types of monopodal weight bearing

Estudou-se a ação muscular na biomecânica da extremidade proximal do têmur com o intuito de acrescentar um parâmetro objetivo nas decisÒes médicas quanto à sustentação do peso e à reabilitação após fraturas nessa região. Foram avaliadas, por meio da eletromiografia de superfície, as atividades elétricas de cinco músculos da região do quadril de 40 voluntários sadios, nove femininos e 31 masculinos, com idade entre 21 e 55 anos, em quatro situaçÒes diferentes, sendo três com carga e um sem carga. As mediçÒes foram realizadas estaticamente, em ortostase. Observou-se que a situação de apoio total proporcionou atividade elétrica muscular global significativamente menor e melhor distribuída entre os grupos musculares, em comparação com as outras situaçÒes propostas

Método de avaliaçäo da hipotrofia muscular por desuso empregando eletromiografia de superfície / Evaluation method of the muscular hypotrophy caused by lack of use employing surface electromyography

This article presents an evaluation method of muscular atrophy caused by lack of use, employing surface electromyography.Describes a new instrument to measure muscular activity in a practical an reliabe way.For the performance of 96 tests, four muscles were select: wrist flexors, biceps rectus femoris, and the gastrocnemius.These were implemented in two groups: (1) comtrol group and (2) experimental group.The results obtained in all muscular groups measurered showed that the reason reference/affected in group (2) presented a variation of 27 percentage to 142 percentage comparared to reason dominant / contralateral in group (1), confirming the unbalance among the members in the experimental group.In the control group the variabily was much smaller than the difference obtained in the limbs tested, showing this to be an auxiliary instrument in prescription an evolution of rehabilitation treatments