A biocomplex to repair experimental critical size defects associated with photobiomodulation therapy

The association of scaffolds to repair extensive bone defects can contribute to their evolution and morphophysiological recomposition. The incorporation of particulate biomaterials into three-dimensional fibrin bioproducts together with photobiomodulation therapy (PBM) has potential and can improve regenerative medicine procedures. The objective of this experiment was to evaluate the effects of PBM therapy on critical size defects filled with xenogenic bone substitute associated with fibrin biopolymer. Methods: A critical defect of 8 mm was performed in 36 Wistar male adult rats that were divided into four groups. Groups BC and BC-PBM were defined as controls with defects filled by a clot (without or with PBM, respectively) and groups XS and XS-PBM that comprised those filled with biocomplex Bio-OssTM in association with fibrin biopolymer. PBM was applied immediately after the surgery and three times a week every other day, with the parameters: wavelength of 830 nm, energy density 6.2 J/cm2, output power 30 mW, beam area of 0.116 cm2, irradiance 0.258,62 W/cm2, energy/point 0.72 J, total energy 2.88 J. Fourteen and 42 days after the surgery, animals were euthanatized and subjected to microtomography, qualitative and quantitative histological analysis. Results: The BC-PBM and XS-PBM groups had a similar evolution in the tissue repair process, with a higher density of the volume of new formed bone in relation to the groups without PBM (p = 0.04086; p = 0.07093, respectively). Intense vascular proliferation and bone deposition around the biomaterial particles were observed in the animals of the groups in which biocomplex was applied (XS and XS-PBM). Conclusion: PBM therapy allowed an improvement in the formation of new bone, with a more organized deposition of collagen fibers in the defect area. Biocomplex favored the insertion and permanence of the particulate material in bone defects, creating a favorable microenvironment for accelerate repair process.(AU)

Effect of electrophysical resources on healing of neurotendinous injury in an experimental model of type I diabetes and kidney disease

Purpose: To evaluate and describe the effect of electrophysical resources laser therapy (LLLT), intravascular laser blood irradiation (ILIB), and cryotherapy on the healing process of neurotendinous injury, as well as possible systemic changes, in the experimental model of type 1 diabetes associated with kidney injury. Methods: The animals were randomized into four groups: G1) healthy control with untreated injury; G2) healthy control with injury and treatment; G3) disease control with untreated lesion; G4) disease with injury and treatment. Furthermore, the treated groups were divided into three, according to the type of treatment. All animals were induced to neurotendinous injury and treated according to the therapeutic protocols. Healing and inflammation were analyzed by semiquantitative histopathological study. Results: It was observed in sick animals treated with cryotherapy and ILIB reduction of inflammatory exudate, presence of fibroblasts and organization of collagen, when compared to the effects of LLLT. Moreover, there was reduction in glycemic levels in the group treated with ILIB. Conclusions: Cryotherapy promoted reduction in inflammatory exudate and organization of collagen fibers, in addition to the absence of signs of tissue necrosis, in the groups treated with and without the disease. ILIB therapy showed the same findings associated with significant reduction in glycemic levels in the group of diseased animals. The application of LLLT showed increased inflammatory exudate, low organization of collagen fibers and low sign of tissue degeneration and necrosis. This study in a model of associated diseases (diabetes and kidney disease) whose effects of electrophysical resources studied after neurotendinous injury allows us to verify histopathological variables suggestive of patients with the same comorbidities.

A biocomplex to repair experimental critical size defects associated with photobiomodulation therapy

Abstract Background: The association of scaffolds to repair extensive bone defects can contribute to their evolution and morphophysiological recomposition. The incorporation of particulate biomaterials into three-dimensional fibrin bioproducts together with photobiomodulation therapy (PBM) has potential and can improve regenerative medicine procedures. The objective of this experiment was to evaluate the effects of PBM therapy on critical size defects filled with xenogenic bone substitute associated with fibrin biopolymer. Methods: A critical defect of 8 mm was performed in 36 Wistar male adult rats that were divided into four groups. Groups BC and BC-PBM were defined as controls with defects filled by a clot (without or with PBM, respectively) and groups XS and XS-PBM that comprised those filled with biocomplex Bio-OssTM in association with fibrin biopolymer. PBM was applied immediately after the surgery and three times a week every other day, with the parameters: wavelength of 830 nm, energy density 6.2 J/cm2, output power 30 mW, beam area of 0.116 cm2, irradiance 0.258,62 W/cm2, energy/point 0.72 J, total energy 2.88 J. Fourteen and 42 days after the surgery, animals were euthanatized and subjected to microtomography, qualitative and quantitative histological analysis. Results: The BC-PBM and XS-PBM groups had a similar evolution in the tissue repair process, with a higher density of the volume of new formed bone in relation to the groups without PBM (p = 0.04086; p = 0.07093, respectively). Intense vascular proliferation and bone deposition around the biomaterial particles were observed in the animals of the groups in which biocomplex was applied (XS and XS-PBM). Conclusion: PBM therapy allowed an improvement in the formation of new bone, with a more organized deposition of collagen fibers in the defect area. Biocomplex favored the insertion and permanence of the particulate material in bone defects, creating a favorable microenvironment for accelerate repair process.

Effect of low-level laser therapy on the membrane induced by the Masquelet technique at an orthotopic site in rabbits

ABSTRACT Purpose: To evaluate the low-level laser therapy (LLLT) on the membrane induced by the Masquelet technique in rabbits. Methods: Twelve Norfolk rabbits at approximately 3 months of age were used. A 1-cm segmental defect was induced in both radii, which were filled with polymethylmethacrylate cylinder. LLLT was used postoperatively in the bone defect of one of the forelimbs every 48 hours for 15 days. Six rabbits were euthanatized on third and sixth postoperative weeks. Results: In both forelimbs, radiographs showed new bone growth from radius cut ends on the third postoperative week and more advanced stage on the sixth postoperative week. Ultrasound showed induced membrane one week after the surgery. Histologically, there were no significant differences in the semi-quantitative score of inflammation intensity, total number of blood vessels, bone metaplasia, and collagen. The average thicknesses were 2,050.17 and 1,451.96 μm for control membranes and 2,724.26 and 2,081.03 μm for irradiated membranes, respectively, on third and sixth postoperative weeks. Vascular endothelial growth factor A (VEGF-A) and platelet derived growth factor (PDGF) expression were present in the induced membranes of control and irradiated forelimbs, but there was no significant difference. Conclusions: Based on assessment methods, it was not possible to demonstrate the effect of LLLT on the induced membrane.

Antimicrobial photodinamic therapy combined with laser photobiomodulation in the treatment of skin wounds in a dog (Canis lupus familiaris)

Background: Laser photobiomodulation has been used in the treatment of various injuries and diseases. This promotes modulation of the inflammatory process, edema reduction and devitalized tissue regeneration. The advantages of Antimicrobial photodynamic therapy are its easy application and the absence of side effects. Other advantages are the cost of the therapy, minimal damage to animal tissue, the broad spectrum of action, and efficiency against strains resistant to antimicrobials. The aim of this study was to report the clinical and their resolution in a female dog with a traumatic, infected wound treated with laser phototherapy as an alternative therapy method. Case: A 3-year-old bitch Border Collie, weighing 18 kg, from the municipality of Ilhéus, Bahia, Brazil, waspresented for examination with a history of traumatic laceration of the left thoracic member. On the anamnesis, it was reported that the patient presented with laceration of the left thoracic member. The wound was cleaned and an antibiotic [30 mg/kg of 12/12 h] and anti-inflammatory [0.1 mg/kg every 24 h were prescribed, both for 5 days]. Twenty-four h after the surgical procedure, there was dehiscence of the sutures, with daily topical therapy based on zinc oxide for secondary intention healing. Upon physical examination, the wound was found to be contaminated with swollen and erythematous edges, an ulcerated area with devitalized tissue, serous exudate, and 8.8 cm2 of wounded area. Given the macroscopic characteristics of the lesion, phototherapy was associated with conventional therapy until complete healing of the wound, with three weekly applications at 48 h intervals. Initially, the wound was cleaned with saline solution at 0.9% and a single treatment with aPDT was scheduled due to the high degree of contamination. The dosimetry parameters of irradiation were calculated according to the wounded area with a diode laser of 0.1W of power, continuous emission, spot area of 0.028 cm2, and energy of 9 J per application point. A gauze imbibed with 1 mL of methylene blue aqueous solution (300 µM), which was the photosensitizer was applied to the lesion, with a pre-irradiation time of 5 min, after which it was irradiated with red laser (RL) (λ = 660nm) for 90 s per point, using the sweeping technique. The edge of the lesion was irradiated with infrared laser (IRL) (λ = 808 nm), total energy of 5 J, using the technique of specific points and 1 J of energy/point. After aPDT, low-intensity laser therapy (LILT) sessions were set up with RL and IRL, with energies of 0.5 J/point and 1 J/point, respectively. The wound was cleaned daily, protected with a bandage, and clinically evaluated until complete regression. Discussion: In the present case, methylene blue was used as a photosensitizer, but it is noteworthy that, apparently, each microorganism responds differently to photosensitizers. Thus, the therapy becomes specific for each application, for example: the type of photosensitizer, its concentration, pre-irradiation time, type of light used in photosensitization, wavelength, energy, power, mode delivery of light. Thus, for the best result, the specific protocol in each application should be used Low-intensity laser therapy is an easily executed technique with effective results. The use of PDT associated with photobiomodulation therapy enabled rapid healing of the cutaneous wound, in addition to an improvement in clinical signs and pain caused by the lesion. The technique proved to be an efficient alternative in the treatment of wounds, whether used in isolation or associated with conventional therapy.

Effect of low intensity photobiomodulation associated with norbixin-based poly (hydroxybutyrate) membrane on post-tenotomy tendon repair: in vivo study

Purpose: To evaluate the in vivo response of photobiomodulation therapy associated with norbixin-based poly(hydroxybutyrate) membrane (PHB) in tenotomized calcaneal tendon. Methods: Thirty rats were randomly allocated to six groups (n=5 each): LED groups (L1, L2 and L3) and membrane + LED groups (ML1, ML2 and ML3). The right calcaneal tendons of all animals were sectioned transversely and were irradiated with LED daily, one hour after surgery every 24 hours, until the day of euthanasia. At the end of the experiments the tendons were removed for histological analysis. Results: The histological analysis showed a significant reduction in inflammatory cells in the ML1, ML2 and ML3 groups (p=0.0056, p=0.0018 and p 0.0001, respectively) compared to those in the LED group. There was greater proliferation of fibroblasts in the ML1 (p 0.0001) and L3 (p 0.0001) groups. A higher concentration of type I collagen was also observed in the ML1 group (p=0.0043) replacing type III collagen. Conclusion: Photobiomodulation in association with norbixin-based PHB membrane led to control of the inflammatory process. However, it did not favor fibroblast proliferation and did not optimize type I collagen formation in the expected stage of the repair process.(AU)

Effect of low power laser in biomodulation of cultured osteoblastic cells of Wistar rats

Purpose:To analyze aspects of the biomodulating effect of light in biological tissues, bone cells from surgical explants of the femur of rats were irradiated with low intensity laser.Methods:Bone cells were cultured and irradiated with LASER light (GaAlAs). Growth, cell viability, mineralized matrix formation, total protein dosage, immunostimulatory properties, cytochemical analysis, gene expression of bone proteins were examined using live cell imaging and cell counting by colorimetric assay. The gene expression of: alkaline phosphatase (ALP), type 1 collagen, osteocalcin and osteopontin through the real-time polymerase chain reaction.Results:At 8 days, the viability of the irradiated culture was 82.3% and 72.4% in non-irradiated cells. At 18 days, the cellular viability (with laser) was 77.42% and 47.62% without laser. At 8 days, the total protein concentration was 21.622 mg / mol in the irradiated group and 16, 604 mg / mol in the non-irradiated group and at 18 days the concentration was 37.25 mg / mol in the irradiated group and 24, 95 mg / mol in the non-irradiated group.Conclusion:The laser interfered in the histochemical reaction, cell viability, matrix mineralization, and maintained the cellular expression of proteins.(AU)

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.(AU)

Laserterapia Para Tratamento De Tendinopatia Induzida Em Ratos Wistar: Estudo Histomorfométrico / Laser Therapy For Treatment Of Tendinopathy Induced In Wistar Rats: An Histomorfometric Study / Terapia Con Láser Para Tratamiento De Tendinopatia Inducida En Ratas Wistar: Estudio Histomorfométrico

O objetivo desse estudo foi avaliar os efeitos da laserterapia na lesão do tendão calcanear comum de ratos Wistar. Foram utilizados 12 ratos machos adultos, distribuídos aleatoriamente em dois grupos (L=laser e C=controle). Todos foram submetidos à tendinopatia unilateral (escolha aleatória) mediante compressão transversal do tendão (10 segundos) com pinça Halstead mosquito, assim como escarificações (com bisturi). Após 24 horas da indução da lesão os animais do grupo L receberam laser (904 nm/3 J/cm²/9s) por 20 dias. Os do grupo C foram manipulados como se fossem receber a radiação. Após 3, 7, 14 e 21 dias da realização da lesão, três ratos de cada grupo foram submetidos à eutanásia, e os tendões obtidos para análise histomorfométrica. As amostras foram processadas como de rotina e os fragmentos corados com hematoxilina-eosina, tricrômico de Masson e Picrosirius Red. Os dados foram analisados por ANOVA, a 5% de probabilidade e análise de regressão. Não houve diferença entre grupos nem entre tempos para as características hemorragia, angiogênese, espessamento do epitendão. Independente do tratamento ocorreu diminuição (p=0,0129) da formação de aderência fibrinosa (do 3o ao 21o dias). Por outro lado, a avaliação morfométrica revelou maiores (p=0,0120) quantidades de fibroblastos no grupo que recebeu laserterapia, não havendo efeito de tempo. Avaliação semiquantitativa, revelou maiores (p=0,0000) quantidades de fibroblastos no grupo tratado, porém nessa análise, a quantidade dessas células aumentou com o tempo (p=0,0001) em ambos os grupos. Diferentemente, ANOVA revelou redução do infiltrado inflamatório do 3o ao 21o dia em ambos os grupos (histologia: p=0,0003; morfometria: p=0,0000).(AU)

The aim of this study was to evaluate the effects of laser therapy in tendinopathy of Achilles tendon of Wistar rats. Thus, 12 adult male rats which were divided into two groups (L=laser and C=control) were used. All animals were submitted to unilateral tendinopathy (random selection) by transverse compression of the tendon (10 seconds) with Halsted forceps, as well as 10 scarifications (using a scalpel). After 24 hours of induction of lesion all animals of Group L received laser (904 nm/3 J/cm²/ 9 s) for 20 days, while Group C were handled as if they would receive radiation. After 3, 7, 14 and 21 days lesion induction, three rats from each group were euthanized, and the tendons obtained for histomorphometric analysis. The samples were processed as routine and the sections stained with hematoxylin-eosin, Masson's trichrome and Picrosirius Red. Data were analyzed by ANOVA, at 5% probability and regression analysis. No differences between groups neither between time for hemorrhage characteristics, angiogenesis, thickening of epitendon. Independently of the treatment there was a decrease (p=0.0129) of fibrinous adhesion (3rd to 21st day). On the other hand, morphometric analysis revealed higher (p=0.0120) amounts of fibroblasts cells in the group receiving laser therapy, with no effect of time. Semiquantitative assessment also showed higher (p=0.0000) amounts of fibroblasts cells in the treated group, but in this analysis, the number of fibroblasts increased with time (p=0.0001) in both group. In contrast, ANOVA revealed a reduction of the inflammatory cells from 3rd to 21st day in both groups (histology: p=0.0003; morphometry: p=0.0000).(AU)

La finalidad de ese estudio fue evaluar los efectos del láser en la lesión del tendón calcáneo común de ratas Wistar. Fueron utilizadas 12 ratas machos adultos, distribuidos al azar en dos grupos (L=láser y C=control). Todos fueron sometidos a tendinopatía unilateral (selección aleatoria) por la compresión transversal del tendón (10 segundos) con una pinza Halstead-Mosquito, y escarificación (con bisturí). Después de 24 horas de la inducción de la lesión los animales del grupo L recibieron láser (904 nm/3J/ cm²/9s) durante 20 días. Los tendones del grupo C fueran manejados como si recibera la radiación. Después de 3, 7, 14 y 21 días de realización de la lesión, tres ratas de cada grupo fueron sacrificadas, y los tendones obtenidos para análisis histomorfométrico. Las muestras fueron procesadas como de rutina y los fragmentos se tiñeron con hematoxilina-eosina, tricrómico de Masson y Picrosirius Red. Los datos fueron analizados por ANOVA, con una probabilidad de 5%, además de análisis de regresión. No hubo diferencias entre los grupos o tiempos para las variables hemorragia, angiogénesis, engrosamiento del epitendón. Independientemente del tratamiento se redujo (p=0,0129) la formación de adherencia fibrinosa (del 3o al 21o días). Por otra parte, la evaluación morfométrica mostró cantidades más altas (p=0,0120) de los fibroblastos en el grupo que recibió el tratamiento con láser, sin efecto del tiempo. Evaluación semicuantitativa reveló mayor (p=0,0000) cantidad de fibroblastos en el grupo tratado, pero en esa análisis la cantidad de esas células aumentó con el tiempo (p=0,0001) en ambos grupos. En contraste, ANOVA reveló reducción del infiltrado inflamatorio entre el 3o y el 21o días, en ambos grupos (histología: p=0,0003; morfometría: p=0,0000). Aunque no hubo diferencias entre grupos en la cantidad de fibras de colágeno (I y III), la morfometría reveló que las ratas del grupo L presentaram mayores cantidades (p=0,0096) de fibras de colágeno.(AU)

Laserterapia Para Tratamento De Tendinopatia Induzida Em Ratos Wistar: Estudo Histomorfométrico / Laser Therapy For Treatment Of Tendinopathy Induced In Wistar Rats: An Histomorfometric Study / Terapia Con Láser Para Tratamiento De Tendinopatia Inducida En Ratas Wistar: Estudio Histomorfométrico

O objetivo desse estudo foi avaliar os efeitos da laserterapia na lesão do tendão calcanear comum de ratos Wistar. Foram utilizados 12 ratos machos adultos, distribuídos aleatoriamente em dois grupos (L=laser e C=controle). Todos foram submetidos à tendinopatia unilateral (escolha aleatória) mediante compressão transversal do tendão (10 segundos) com pinça Halstead mosquito, assim como escarificações (com bisturi). Após 24 horas da indução da lesão os animais do grupo L receberam laser (904 nm/3 J/cm²/9s) por 20 dias. Os do grupo C foram manipulados como se fossem receber a radiação. Após 3, 7, 14 e 21 dias da realização da lesão, três ratos de cada grupo foram submetidos à eutanásia, e os tendões obtidos para análise histomorfométrica. As amostras foram processadas como de rotina e os fragmentos corados com hematoxilina-eosina, tricrômico de Masson e Picrosirius Red. Os dados foram analisados por ANOVA, a 5% de probabilidade e análise de regressão. Não houve diferença entre grupos nem entre tempos para as características hemorragia, angiogênese, espessamento do epitendão. Independente do tratamento ocorreu diminuição (p=0,0129) da formação de aderência fibrinosa (do 3o ao 21o dias). Por outro lado, a avaliação morfométrica revelou maiores (p=0,0120) quantidades de fibroblastos no grupo que recebeu laserterapia, não havendo efeito de tempo. Avaliação semiquantitativa, revelou maiores (p=0,0000) quantidades de fibroblastos no grupo tratado, porém nessa análise, a quantidade dessas células aumentou com o tempo (p=0,0001) em ambos os grupos. Diferentemente, ANOVA revelou redução do infiltrado inflamatório do 3o ao 21o dia em ambos os grupos (histologia: p=0,0003; morfometria: p=0,0000).

The aim of this study was to evaluate the effects of laser therapy in tendinopathy of Achilles tendon of Wistar rats. Thus, 12 adult male rats which were divided into two groups (L=laser and C=control) were used. All animals were submitted to unilateral tendinopathy (random selection) by transverse compression of the tendon (10 seconds) with Halsted forceps, as well as 10 scarifications (using a scalpel). After 24 hours of induction of lesion all animals of Group L received laser (904 nm/3 J/cm²/ 9 s) for 20 days, while Group C were handled as if they would receive radiation. After 3, 7, 14 and 21 days lesion induction, three rats from each group were euthanized, and the tendons obtained for histomorphometric analysis. The samples were processed as routine and the sections stained with hematoxylin-eosin, Masson's trichrome and Picrosirius Red. Data were analyzed by ANOVA, at 5% probability and regression analysis. No differences between groups neither between time for hemorrhage characteristics, angiogenesis, thickening of epitendon. Independently of the treatment there was a decrease (p=0.0129) of fibrinous adhesion (3rd to 21st day). On the other hand, morphometric analysis revealed higher (p=0.0120) amounts of fibroblasts cells in the group receiving laser therapy, with no effect of time. Semiquantitative assessment also showed higher (p=0.0000) amounts of fibroblasts cells in the treated group, but in this analysis, the number of fibroblasts increased with time (p=0.0001) in both group. In contrast, ANOVA revealed a reduction of the inflammatory cells from 3rd to 21st day in both groups (histology: p=0.0003; morphometry: p=0.0000).

La finalidad de ese estudio fue evaluar los efectos del láser en la lesión del tendón calcáneo común de ratas Wistar. Fueron utilizadas 12 ratas machos adultos, distribuidos al azar en dos grupos (L=láser y C=control). Todos fueron sometidos a tendinopatía unilateral (selección aleatoria) por la compresión transversal del tendón (10 segundos) con una pinza Halstead-Mosquito, y escarificación (con bisturí). Después de 24 horas de la inducción de la lesión los animales del grupo L recibieron láser (904 nm/3J/ cm²/9s) durante 20 días. Los tendones del grupo C fueran manejados como si recibera la radiación. Después de 3, 7, 14 y 21 días de realización de la lesión, tres ratas de cada grupo fueron sacrificadas, y los tendones obtenidos para análisis histomorfométrico. Las muestras fueron procesadas como de rutina y los fragmentos se tiñeron con hematoxilina-eosina, tricrómico de Masson y Picrosirius Red. Los datos fueron analizados por ANOVA, con una probabilidad de 5%, además de análisis de regresión. No hubo diferencias entre los grupos o tiempos para las variables hemorragia, angiogénesis, engrosamiento del epitendón. Independientemente del tratamiento se redujo (p=0,0129) la formación de adherencia fibrinosa (del 3o al 21o días). Por otra parte, la evaluación morfométrica mostró cantidades más altas (p=0,0120) de los fibroblastos en el grupo que recibió el tratamiento con láser, sin efecto del tiempo. Evaluación semicuantitativa reveló mayor (p=0,0000) cantidad de fibroblastos en el grupo tratado, pero en esa análisis la cantidad de esas células aumentó con el tiempo (p=0,0001) en ambos grupos. En contraste, ANOVA reveló reducción del infiltrado inflamatorio entre el 3o y el 21o días, en ambos grupos (histología: p=0,0003; morfometría: p=0,0000). Aunque no hubo diferencias entre grupos en la cantidad de fibras de colágeno (I y III), la morfometría reveló que las ratas del grupo L presentaram mayores cantidades (p=0,0096) de fibras de colágeno.

The effects of photobiomodulation therapy on Staphylococcus aureus infected surgical wounds in diabetic rats. A microbiological, histopathological, and biomechanical study

PURPOSE:To evaluate the effects of photobiomodulation therapy (PBMT) at 685 nm on diabetic wound healing in rats suffering from bacterial infection induced by Staphylococcus aureus (S. aureus).METHODS:Thirty streptozotocin-induced diabetic rats were allocated into two groups: control and PBMT. A 4-cm full-thickness linear-incision was made on the dorsal midline and was contaminated with S. aureus. The wounds in the PBMT group were irradiated daily for 5 consecutive days, starting 3 days after the induction and always in the mornings.RESULTS:The result revealed that PBMT resulted in a significant decrease in S. aureus CFU in the PBMT group in comparison to the control group (P<0.05). The length of wounds, in the 2nd and 3rd weeks, in the PBMT group were significantly shorter compared to the control group (P<0.05). PBMT caused a significant increase in the histological parameters in comparison to the control group (P<0.05). Moreover, PBMT significantly increased the breaking strength of the surgical scars produced in the skin of the PBMT group when compared to the control group (P<0.05).CONCLUSION:Photobiomodulation therapy may be useful in the management of wound infection through a significant bacterial growth inhibition and an acceleration of wound healing process.(AU)

The effects of low level laser therapy on Staphylococcus aureus infected third-degree burns in diabetic rats

PURPOSE:To characterize the effects of low-level laser (LLL) on third-degreeburn wounds which were infected with Staphylococcus aureus (S. aureus) in diabetic rats.METHODS:Thirty streptozotocin-induced diabetic rats were divided into two groups: the control and the LLL groups. Third-degree burns were induced using a heated metal rod, and then, were contaminated with S. aureus. The wounds in the LLL group were irradiated with a LLL (685nm) daily for five consecutive days, starting three days after the induction. The wound area was measured at 3, 5, 8, 14 and 21 days after burning. At the end of trial, the skin samples were harvested.RESULTS:Reduction in wound areas in the LLL and control groups were significantly different only on the 21st day (p<0.05). The mean bacterial numbers in the LLL group were significantly lower (p<0.05) than those in the control group.The number of macrophages, new blood vessels, fibroblast, and elevated collagen deposition in the LLL group significantly increased compared to the control group (p<0.05).The mean breaking strength of scars in the control group was significantly lower (p<0.05) than that of the LLL group.CONCLUSION:The low-level laser improved the healing of S. aureus third-degree burn infections in diabetic rats.(AU)

EFEITOS DO LASER E ULTRASSOM TERAPÊUTICO DE BAIXAS INTENSIDADES NA CICATRIZAÇÃO DE RETALHOS SUBDÉRMICOS EM RATOS (Rattus novergicus albinus wistar)

As técnicas reconstrutivas empregadas na ressecção do neoplasma são boas opções de tratamento quando há perda cutânea significativa, como no caso de traumas e exérese de neoplasias e apresentam resultados satisfatórios; todavia, a principal desvantagem das técnicas está relacionada com a vascularização local, sendo esta a mais importante causa de complicações. Partindo deste princípio, o objetivo deste trabalho foi avaliar os efeitos da aplicação de laser de baixa intensidade e ultrassom terapêutico após a confecção de defeitos cirúrgicos submetidos ao uso de retalhos de padrão subdérmico. Para isso foram utilizados 30 ratos machos, sendo submetidos a um defeito cutâneo de 8 cm x 2,4 cm em região dorsal, tendo 3 distintos tratamentos (G1, G2 e G3), controle, laser de baixa intensidade 4J/cm2 e ultrassom terapeutico 0,5W/cm2, administrados um dia após a cirurgia, três dias após e cinco dias após (D1, D3 e D5, respectivamente) Entre os itens analisados no presente estudo, sendo estes as variáveis macroscópicas (presença de secreção, presença de tecido desvitalizado, edema e deiscência de sutura) e microscópicas (presença de necrose, quantidade de vasos sanguíneos, infiltrado neutrofílico e macrofágico correspondente à inflamação), dentro dos testes realizados não apresentaram significância nem diferenciação estatística, seja entre os grupos (relacionados à comparação entre os tratados e o controle, e entre os distintos grupos tratados).

The reconstructive techniques used in the resection of the neoplasm are good treatment options when there is reduced skin loss, as in the case of trauma and excision of neoplasms and present satisfactory results; however, the main disadvantage of the techniques is related to local vascularization, which is the most important cause of complications. Starting from the beginning, the objective of this work was to evaluate the effects of applying low-level laser and therapeutic ultrasound after making surgical defects when using subdermal pattern flaps. For this, 30 male rats were used, receiving a skin defect of 8 cm x 2.4 cm in the dorsal region, having 3 different treatments (G1, G2 and G3), control, low intensity laser 4J / cm2 and therapeutic ultrasound 0, 5W / cm2, administered one day after surgery, three days after and five days after (D1, D3 and D5, respectively) Among the objective items in the present study, these being macroscopic variables (presence of secretion, presence of tissue devitalized, edema and suture dehiscence) and microscopic (presence of necrosis, number of blood vessels, neutrophilic and macrophage infiltrate - corresponding to inflammation), within the tests carried out neither impartial significance nor statistical differentiation, either between the groups (related to the comparison between treated and control and between the different treated groups).

Low-level laser therapy modulates musculoskeletal loss in a skin burn model in rats

PURPOSE: To investigate the effectiveness of low-level laser therapy (LLLT) on gastrocnemius muscle morphology and Myod imunoexpression in a model of dorsal burn in rats. METHODS: Sixteen male Wistar rats were distributed into two groups: control group (CG): rats submitted to scald burn injury without treatment and laser treated group (LG): rats submitted to scald burn injury and treated with laser therapy. Fourteen days post-surgery, gastrocnemius muscle was evaluated being the specimens stained with HE and morphometric data was evaluated. MyoD expression was assessed by immunohistochemistry. RESULTS: The results showed that laser treated animals presented more organized tissue morphology compared to the non-treated animals, with a higher number of nucleus in the fibers. Also, the cross sectional area of the fibers and the MyoD immunoexpression in the laser treated groups was higher. CONCLUSION: Low-level laser therapy had positive effects on gastrocnemius muscle, improving tissue muscle morphology, increasing cross sectional area and MyoD immunoexpression.(AU)

Effects of the Low-Level Laser Therapy (LLLT) in the process of healing diabetic foot ulcers

To evaluate the effects of the low-level laser therapy applying Laser on the tissue repair in ulcer carriers due to diabetes. METHODS: Sixteen type II diabetic patients, ulcer carriers in the lower limbs, participated in the research from which eight were in the control group and eight were submitted to the low-level laser therapy with a pulsed wave form, visible ray, wave length of 632.8 nm, 30 mW peak power, (Laser - HTM). The application time was of 80 (4J/cm2) seconds. The application was punctual without contact (approximately 1mm of distance), the pen being held in a perpendicular position related to the wound, in equidistant points. There were 12 appointments, of which three were done weekly in alternated days. Photograph records and an application of the brief inventory of pain were done before and after 30 days of follow-up. RESULTS: There was a significant decrease in the size of the wound when compared to the control group (p 0.05). The pain was also reported as having an intense improvement in the treated group. CONCLUSION: The low-level laser treatment seems to be an efficient method, viable, painless and of low costs concerning the tissue repair ulcers in a diabetic foot.(AU)

Analysis of the healing process of the wounds occurring in rats using lasertherapy in association with hydrocolloid

To evaluate wound healing in rats by using low-level laser therapy (LLLT) associated with hydrocolloid occlusive dressing . METHODS: Forty male, adult, Wistar rats were used, distributed into four groups: LG (received 2 J/cm² of laser therapy); HG (treated with hydrocolloid); LHG (treated with 2 J/cm² of laser therapy and hydrocolloid); and the CG (treated with 1 mL of 0.9% saline). The wound was evaluated at pre-determined periods 3rd and 7th days, considering the macroscopic and histological parameters (inflammatory cells, capillary neoformation, fibroblasts, collagen formation and reepithelialization). RESULTS: The LG group at seven days showed increased collagen formation, the LHG group at 3 days showed mild collagen formation. The HG group and the CG at 7 days showed complete reepithelialization. CONCLUSION: Low-level laser therapy as well as the hydrocolloid dressing have favored the wound-healing process in rats.(AU)

The influence of low-level laser irradiation on spinal cord injuries following ischemia- reperfusion in rats

To investigate if low level laser therapy (LLLT) can decrease spinal cord injuries after temporary induced spinal cord ischemia-reperfusion in rats because of its anti-inflammatory effects. Forty eight rats were randomized into two study groups of 24 rats each. In group I, ischemic-reperfusion (I-R) injury was induced without any treatment. Group II, was irradiated four times about 20 minutes for the following three days. The lesion site directly was irradiated transcutaneously to the spinal direction with 810 nm diode laser with output power of 150 mW. Functional recovery, immunohistochemical and histopathological changes were assessed. The average functional recovery scores of group II were significantly higher than that the score of group I (2.86 ± 0.68, vs 1.38 ± 0.09; p<0.05). Histopathologic evaluations in group II were showed a mild changes in compare with group I, that suggested this group survived from I-R consequences. Moreover, as seen from TUNEL results, LLLT also protected neurons from I-R-induced apoptosis in rats. Low level laser therapy was be able to minimize the damage to the rat spinal cord of reperfusion-induced injury.(AU)

Improvement of bone repair in diabetic rats subjected to 780 nm low-level laser therapy

To investigate the effect of low-level laser therapy on bone healing in diabetic rats. METHODS: Bone cavities (19 mm diameter) were performed in the femur of 72 alloxan-induced diabetic rats, which were assigned into four groups: CTR (non-diabetic control), DBT (diabetic) CTRL (non-diabetic irradiated) and DBTL (diabetic irradiated). Low-level laser therapy was performed every 48h for seven days. Animals were euthanized at seven, 18 and 30 days. Alkaline phosphatase serum levels and bone repair were analyzed. RESULTS: Low-level laser therapy significantly increased alkaline phosphatase in at seven and 18 days (p 0.001), and improved bone healing at seven (p 0.01), 18 (p 0.05) and 30 (p 0.01) in diabetic animals. In addition, bone healing in irradiated diabetic group was statistically similar to control group at 30 days (p>0.05). CONCLUSION: Low-level laser therapy increased the serum levels of alkaline phosphatase and improved bone healing in alloxan-induced diabetic rats.(AU)

The low-level laser on acute myositis in rats

PURPOSE: To analyze the effects of the low-level laser therapy in the acute myositis induced in rats. METHODS: Twelve rats were subjected to bilateral ovariectomy for inducing osteoporosis. After surgery, they were divided into two groups: Ovariectomy-control group (G1, n=6), receiving 0.5 ml distilled water by gavage for 30 days, and Ovariectomy plus mastruz group (G2, n=6), receiving 0.5 ml of the hydroalcoholic extract of mastruz at 10% concentration (50mg) daily, for the same period. Then, the blood of the animals was collected for further biochemical analysis (liver function) and tibia and liver were removed for histological and histomorphometric analyses. RESULTS: In the MT group there was a statistic significant decrease in the number of inflammatory cells, related to the MI group (p 0.05), increase in the fibroblastic proliferation, when compared to groups C and MI related to MT group (p 0.01) and statistic significant edema regression (p=0.0400) in the MT group CONCLUSION: The low-level laser therapy was efficient in the reduction of the inflammatory process, increase of the fibroblastic proliferation and the reduction of the edema.(AU)

AVALIAÇÃO DA ANGIOGÊNESE E RESPOSTA INFLAMATÓRIA EM ENXERTOS CUTÂNEOS SUBMETIDOS À LASERTERAPIA EM RATOS (Rattusnovergicusalbinuswistar)

As técnicas reconstrutivas têm sido amplamente utilizadas na Medicina Veterinária. Com a intenção de reduzir complicações inerentes às técnicas reconstrutivas, são utilizadas terapias adjuvantes pós-operatórias como a laserterapia de baixa intensidade (LBI). Objetivou-se definir os efeitos da laserterapia de baixa intensidade sobre a cicatrização, inflamação e vascularização de enxertos cutâneos em intervalos de tempo aplicáveis à rotina cirúrgica veterinária. Foram utilizados 40 ratos (Rattusnovergicusalbinuswistar), sendo cada animal submetido à enxertia cutânea autógena em região interescapular, sendo distribuídos de forma aleatória em cinco grupos (G1, G2, G3, G4 e G5) de acordo com a dose de 6 J/cm² ou 10 J/cm² a cada 3 ou 5 dias, aplicada sobre o enxerto cutâneo durante 15 dias. Avaliação macroscópica aos dias três, sete e 15 não demonstrou alteração com a aplicação de LBI sobre os enxertos. Avaliação histoquímica com picrosirius apresentou maior expressão de colágeno tipo I vermelho em enxertos de G5 (p<0,05), enquanto não houve expressão do mesmo em G1; a expressão de colágeno tipo III verde não foi influenciada pela LBI. A avaliação histoquímica com hematoxilina-eosina evidenciou maior número de fibroblastos em enxertos de G4 (p<0,05) e menor hemorragia em enxertos de G5 (p<0,05). Houve modulação da resposta inflamatória em enxertos cutâneos irradiados, enquanto a LBI não teve efeito sobre a angiogênese. Conclui-se que a exposição de enxertos cutâneos à dose de energia de 6 J/cm² ou 10 J/cm² a cada 5 dias beneficiaram a cicatrização e a modulação da inflamação local.

The reconstructivetechniqueshasbeenwidelyused in Veterinary Medicine. Toreduceinherentcomplicationstothereconstructivetechniques, thepostoperativeadjuvantstherapies are used, such as low-level laser therapy (LLLT). The aimofthiswork is to determine the low-level laser therapyseffectsonthe healing, inflammationandvascularizationofthefree skin graftsgrafts in applicable time intervalstothe veterinary surgeryroutine. Forty rats (Rattus novergicusalbinuswistar) wereused, andeachonewassubmittedtotheautogenousfree skin graftontheinterescapular region. Theywereallocatedrandomly in fivegroups (G1, G2, G3, G4 and G5) accordingtothe 6 J/cm² or 10 J/cm² doses every 3 or 5 days for 15 days. The macroscopicevaluationonthethird, seventhandfifteenthdaydidnot show alterationsofthe LLLT onthegrafts. The histochemicalevaluation with picrosirius had more expressionofthetype I collagenous red in thegraftsof G5 (p<0,05), while in the G1 didnot; theexpressionofthetype III collagenous greenwasnotinfluencedby LPLT. The histochemicalevaluation with hematoxylin-eosinshowed more numbersoffibroblasts in thegraftsof G4 (p<0,05) andlesshemorrhage in graftsof G5 p<0,05). It hadmodulationofthe inflammatory response in theirradiatedcutaneousgrafts, whilethe LPLT had no effectontheangiogenesis. Then, it observedthattheexposureofthecutaneousgraftstothe 6 J/cm² or 10 J/cm² doses every 5 daysimprovedthe healing andthemodulationofthe local inflammation.