Does low-intensity pulsed ultrasound accelerate phasic calcium phosphate ceramic-induced bone formation?

Purpose: Low-intensity pulsed ultrasound (LIPUS) has been used to stimulate the healing of the fresh fracture, delayed union, and non-union in both animal and clinical studies. Besides, biphasic calcium phosphate ceramic (BCP) is a promising biomaterial for bone repair as it shows favorable biocompatibility, osteoinduction, and osteoconduction. However, scarcity is known about the combined effect of LIPUS and BCP on bone formation. Methods: The combined effect of LIPUS and BCP was studied in a beagle model. Twelve dogs were used. BCP granules without any additions were implanted into bilateral erector spinae muscles. One side is the BCP group, while the counterlateral side is LIPUS + BCP group. Histological and histomorphometric analyses, and quantitative real-time polymerase chain reaction were evaluated. Results: Compared with BCP alone, the LIPUS + BCP showed no advantages in early bone formation. Furthermore, the Notch signaling pathway-related mRNA has no significant difference between the two groups. Conclusions: The preliminary results showed that the BCP, which has intrinsic osteoinduction nature, was an effective and promising material. However, LIPUS has no enhanced effect in BCP induced ectopic bone formation. Furthermore, LIPUS has no effect on the Notch signaling pathway. Whether costly LIPUS could be used in combination with BCP should be a rethink.

Uso da termografia e ultrassonografia power dopplerpara avaliação da resposta tecidual em falhas ósseas preenchidas com biomaterial em ovinos / Termography and power doppler sonography assessment for tissue response evaluation in sheep bone defects filled with biomaterial

Biomateriaistem diversas indicações como auxiliares no processo de reparação óssea, além de terem função de substituto ósseo em perdas extensas. Diversas são as vantagens de sua utilização, como por exemplo, auxílio na osteocondutividade, estímulo de neovascularização, potencial antimicrobiano, entre outros. Falhas ósseas foram realizadas nas tíbias de seis ovinos da raça Santa Inês e preenchidas com biomaterial à base de quitosana, colágeno e hidroxiapatita. Um membro foi considerado controle e outro membro tratado segundo estudo randomizado. Foram realizadas avaliações termográficas e por ultrassonografia Power Dopplerem todos os animais do estudo, semanalmente, nos dias D0, D7, D14, D21, D28, D35, D42 e D56. Não houve diferenças significativas com relação à temperatura mínima, máxima e média entre os grupos com biomaterial e controle nas imagens termográficas. Houveram variações com relação ao tempo dentro de ambos os grupos. Com relação à presença de vasos na ultrassonografia Power Dopplernão houve diferenças estatísticas entre os grupos, exceto no dia 21 (P=0,031). Dentro das possibilidades de avaliação que os exames de imagem fornecem, a termografia e a ultrassonografia Power Dopplermostraram-se ferramentas não invasivas de avaliação pós-operatória de processo inflamatório e neovascularização, sendo realizadas semanalmente, permitindo acompanhamento fidedigno e detalhado ao longo do experimento, sem gerar desconforto ou estresse aos animais. Não houve indícios de complicações relacionadas ao biomaterial.(AU)

Biomaterials have several indications supporting the bone repair process, besides having bone substitute function in extensive losses. There are several advantages of its use, such as contribution in osteoconductivity, stimulation of neovascularization, antimicrobial potential, among others.Tibial bone defects was performed in six Santa Inês breed ewes and implanted with chitosan, collagen and hydroxyapatite biomaterial. One limb was considered the control limb and the other one the biomateriallimb, chosenrandomly. Thermographic and Power Dopplersonography was performed in all animals, weekly for 56 days. The thermography showed no significant differences related to low, high and mean temperature between the control and the biomaterial groups. Statisticalvariations were found between time in both groups. The visualization of neovascularization with the Power Dopplersonography did not present statistical differences, except for day 21 (P=0,031). Within the possibilities provided by imaging exams, thermography and Power Doppler sonography demonstrate to be non-invasive methods for post-operative evaluation of inflammatory process and neovascularization. The weekly management allowed reliable and detailed monitoring throughout the experiment, without causingdiscomfort or stress to the animals. There was no evidence of biomaterial complications.(AU)

Effect of ascorbic acid and epidermal growth factor in a rat tibia defect

Purpose: Bone repair aims to restore the anatomical, biomechanical, and functional integrity of the affected structure. Here we study the effects of ascorbic acid (AA) and epidermal growth factor (EGF) applied in a single dose and in combination on the repair of a noncritical bone defect model. Methods: Twenty-four rats were divided into four groups: an intact G-1 control group, and three groups that underwent a noncritical bone defect in the right tibia: G-2 treated with AA, G-3 treated with EGF, and G-4 treated with AA in combination with EGF. After 21 days of treatment, rats were sacrificed, the tibias were dissected and a destructive biomechanical analysis of three-point flexion test was performed in a universal testing machine; the values of stiffness, resistance, maximum energy, and energy at maximum load were statistically compared. Results: G-3 and G-4 recovered the biomechanical properties of strength and stiffness of an intact tibia 3 weeks after their application. Not so the energy and energy at maximum load. For G-2, only the stiffness of an intact tibia was recovered. Conclusion: EGF and AA-EGF applied to a noncritical bone defect in the rat tibia favors the recovery of bone resistance and stiffness.

Surgical approach in correction of a crack in the gnathotheca of a black swan (Cygnus atratus, Latham, 1790): first case report / Abordagem cirúrgica em correção de fissura na gnatoteca em um cisne-negro (Cygnus atratus, Latham, 1790): primeiro relato de caso

The black swan (Cygnus atratus, LATHAM, 1790) is a bird kept as an ornamental in zoos. Because of their long beaks they tend to have a reserved prognosis in musculoskeletal disorders such as beak trauma, secondary to skull bone fractures, presenting irreversible lesions. The aim of this report is present a clinical surgical innovation in the repair of a black swan's gnathotheca fissure with the application of non-conventional materials used. It was observed that one of the swans kept in a zoo display area had difficulty feeding, with associated weight loss. It was observed tissue loss and a lacerative lesion in the caudal sublingual region of its beak. The lesion was corrected by a separate simple suture in the cranial region of the beak and with a x-clamping using steel surgical wire and the application of dental resin in the distal region to perform a sustentation bridge in the beak end-gap. After 12 days, the animal was able to feed again and remained perfectly adapted to the restoration, reestablishing the anatomical and physiological function of its beak.

O cisne-negro (Cygnus atratus, Latham, 1790) é uma ave mantida como ornamental em zoológicos. Por apresentar bicos longos, tende a ter prognóstico reservado em afecções musculoesqueléticas, como traumas de bico secundários e fraturas de ossos do crânio, com lesões irreversíveis. O objetivo deste relato é apresentar uma inovação clínica cirúrgica no reparo de fissura na gnatoteca de um cisne-negro, com a utilização de materiais não convencionais. Observou-se que um dos cisnes mantidos em uma área de exibição de um zoológico apresentava dificuldade para se alimentar, com perda de peso associada. Constatou-se perda tecidual e lesão lacerativa na região sublingual caudal de seu bico. A lesão foi corrigida por meio de sutura simples separada na região cranial do bico e posterior sutura em x com fio cirúrgico de aço, finalizando com aplicação de resina odontológica na região distal para realização de ponte de sustentação do bico. Após 12 dias, o animal conseguiu se alimentar novamente e se manteve perfeitamente adaptado à restauração, restabelecendo a função anatômica e fisiológica de seu bico.

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.

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)

Development and characterization of poultry collagen-based hybrid hydrogels for bone regeneration

Purpose: Poultry by-products can contribute as an innovative natural source for the development of composites based on polymers and minerals aiming at bone regeneration. The objective of this study was the physicochemical and biological characterization of collagen-based hydrogels crosslinked with ultraviolet (UV)-riboflavin. Methods: Pure hydrogels of 100% collagen (G1) or hybrid hydrogels, 90% collagen:10% apatite (G2), 90% collagen:10% nanokeratin (G3), and 90% collagen:5% apatite:5% nanokeratin (G4) were characterized by scanning electron microscope, Fourier-transform infrared spectroscopy, differential scanning calorimetry, swelling degree and quali-quantitative histological analysis. Ectopic implantation in subcutaneous tissue in mice at one, three and nine weeks allowed to assess the inflammation (neutrophils, lymphocytes, macrophages, and giant cells) and repair (neovascularization, and connective tissue) to determine biocompatibility and the integrity of biomaterials to score their biodegradability. Histomorphometry on critical size defects in rat calvaria at one and three months evaluated the percentage of bone, connective tissue, and biomaterials in all groups. Results: The hydrogels presented porous microstructure, water absorption and physicochemical characteristics compatible with their polymeric and/or mineral composition. All materials exhibited biocompatibility, biodegradability, and low osteoconductivity. G2 showed greater density of new bone and biomaterial than the G1, G3 and G4. Conclusions: The collagen-apatite group formulation suggests potential for development as osteopromoting membrane.

Femoral orthopedic implants in dogs with titanium - mechanical evaluation

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...

Femoral orthopedic implants in dogs with titanium - mechanical evaluation

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...(AU)

Biomechanical comparison of a modified TPLO plate, a locking compression plate, and plate-rod constructs applied medially in a proximal gap model in canine synthetic tibias / [Comparação biomecânica entre placa de TPLO modificada, placa bloqueada e construção placa-pino intramedular aplicadas medialmente em modelo de fratura proximal em tíbias sintéticas caninas]

The aim of this study was to develop a modified tibial plateau leveling osteotomy (TPLO) plate and to compare its biomechanical properties with a locking compression plate (LCP) and plate-rod constructs for the stabilization of experimentally induced gap fractures in canine synthetic tibias. The tibial models were assigned to either repair with a modified TPLO plate (Group 1), locking compression plate construct (Group 2), or plate-rod construct (Group 3). The specimens were loaded to failure in axial compression, three-point mediolateral and craniocaudal bending. There was no statistical difference between the three groups regarding stiffness (N/mm) and deformation (mm) in axial compression. The modified TPLO plate achieved load to failure similar to the plate-rod construct in craniocaudal bending. There was no significant difference between groups on mediolateral bending tests regarding load to failure and deformation. Furthermore, there was no significant difference in stiffness between groups 1 and 2. In conclusion, the modified TPLO plate had similar mechanical properties to LCP and plate-rod construct in the axial compression and bending tests. Nonetheless, clinical studies with a large population of dogs are required to determine the value of this new implant in proximal tibial fracture repair.

Objetivou-se desenvolver uma placa de osteotomia niveladora do platô tibial (TPLO) modificada e compará-la biomecanicamente à placa de compressão bloqueada (LCP) e à construção placa-pino intramedular na estabilização da fratura cominutiva proximal em tíbias sintéticas caninas. Para tal, tíbias caninas sintéticas foram divididas em três grupos, sendo o grupo 1 formado pela placa de TPLO modificada, o grupo 2 por placas LCP e o grupo 3 pela construção placa-pino intramedular. Os espécimes foram submetidos à carga até a falha em compressão axial, flexão mediolateral e craniocaudal em três pontos. Não houve diferença estatística entre os três grupos quanto à rigidez (N/mm) e à deformação (mm) nos testes de compressão axial. A placa de TPLO modificada obteve carga até a falha semelhante à construção placa-pino intramedular em flexão craniocaudal. Não houve diferença significativa entre os grupos nos testes de flexão mediolateral em relação à carga até a falha e a deformação, e a variável rigidez não apresentou diferenças significativas entre os grupos 1 e 2. Em conclusão, a placa de TPLO modificada apresentou similaridade mecânica em comparação com a LCP e a construção placa-pino. No entanto, estudos clínicos são necessários para determinar o valor desse novo implante na fixação de fraturas tibiais proximais.

Resveratrol-Tempeh reduce micronucleus frequencies bone marrow cells and stimulate osteocyte proliferation in aluminum chloride-induced mice / Redução de frequências de micronúcleos células da medula óssea e estímulo proliferação de osteócitos em camundongos induzidos por cloreto de alumínio através do uso de Resveratrol-Tempeh

Aluminum (Al) is widely used for water purification, cooking pots, cosmetic and pharmaceutical preparations, toothpaste tubes, and food processing industries. Although the transport in the digestive tract is very poor but if the load is high, it can be absorbed and accumulated. About 50-70% of Al accumulates in the bones and can have an impact on human health. Resveratrol (RES), isolated from tempeh as an Indonesian food ingredient, can increase cell viability and has promising cytoprotective effects. RES has the capacity to interact with oxidative stress, so it has the potential as a therapy in bone repair. Therefore, this study aimed to evaluate the effect of RES on the number of osteocytes and bone marrow cells in Al-induced mice. Swiss Webster mice were divided into four groups: (1) untreated groups, (2) AlCl3 -treated groups, (3) Al+Res5 treated groups, and (4) Al+Res10 treated groups. Al dose 200 mg/kg body weight was administered intraperitoneally. RES was given one hour after administration of Al, with doses of 5 and 10 mg/kg Body Weight. Al and RES administration is carried out for one month. All mice were sacrificed, and mouse bones were isolated for histological preparations and a half for genotoxic assays. Bone marrow cells were collected and stained with My Grunwald. The number of micronuclei polychromatic erythrocytes (MNPCE) was examined in 1,000 PCEs per animal. The number of PCEs is counted by at least 200 erythrocytes (PCE + NCE) per animal. The results showed that the administration of Al significantly increased the number of micronuclei (MN) but after administration of RES at doses of 5 and 10 mg/kg Body Weight significantly reduced the number of MN in bone marrow cells. A dose of RES 10 mg/kg BW stimulates proliferation and increases the number of osteocytes in bone significantly. It can be concluded that Al can cause genotoxicity in bone marrow cells and RES is anti-genotoxic and can stimulate osteocyte proliferation.

O alumínio (Al) é amplamente utilizado para purificação de água, panelas, preparações cosméticas e farmacêuticas, tubos de pasta de dente e indústrias de processamento de alimentos. Embora o transporte no trato digestivo seja escasso, se a carga for alta, pode ser, todavia, absorvida e acumulada. Cerca de 50-70% do Al se acumula nos ossos e pode ter impacto na saúde humana. O resveratrol (RES), isolado do tempê indonésio como ingrediente alimentar, pode aumentar a viabilidade celular e tem efeitos citoprotetores promissores. O RES possui a capacidade de interagir com o estresse oxidativo, e por essa razão pode ser utilizado como terapia no reparo ósseo. Portanto, este estudo teve como objetivo avaliar o efeito do RES no número de osteócitos e células da medula óssea em camundongos induzidos por Al. Camundongos Swiss Webster (SW) foram divididos em quatro grupos: (1) grupos não tratados, (2) grupos tratados com AlCl3 , (3) grupos tratados com Al+Res5 e (4) grupos tratados com Al+Res10. Uma dose de 200 mg/kg de peso corporal foi administrada por via intraperitoneal. O RES foi administrado uma hora após a administração do Al, nas doses de 5 e 10 mg/kg de peso corporal. A administração de Al e RES foi realizada por um mês. Todos os camundongos foram sacrificados, e os ossos dos camundongos foram isolados para preparações histológicas e meio para ensaios genotóxicos. As células da medula óssea foram coletadas e coradas com My Grunwald. O número de eritrócitos policromáticos micronúcleos (MNPCE) foi examinado em 1.000 PCEs por animal. O número de PCEs foi contado por pelo menos 200 eritrócitos (PCE + NCE) por animal. Os resultados mostraram que a administração de Al aumentou significativamente o número de micronúcleos (MN), mas após a administração de RES nas doses de 5 e 10 mg/kg de peso corporal reduziu significativamente o número de MN nas células da medula óssea. Uma dose de RES de 10 mg/kg BW estimula a proliferação e aumenta significativamente o número de osteócitos no osso. Dessa forma, pôde-se concluir que o Al pode causar genotoxicidade em células da medula óssea e o RES é antigenotóxico e pode estimular a proliferação de osteócitos.

Evaluation of mesenchymal cells and dapsone for the treatment of dermonecrotic wounds caused by Loxosceles laeta venom in rabbits / Avaliação de células mesenquimais e dapsona para o tratamento de feridas dermonecróticas causadas pelo veneno de Loxosceles laeta em coelhos

This study aimed to evaluate the efficacy of mesenchymal stem cells (MSC), alone or associated with dapsone (DAP), in treating dermonecrotic wounds caused by Loxosceles laeta venom. Twenty-five male rabbits were distributed into five groups. Negative control received ultrapure water (C-), whilst all other groups were injected with 20 μg of L. laeta venom. After 4 hours, each group received one of the following treatments: PBS (C+), DAP, MSC, and DAP+MSC. Animals were evaluated daily and photographic records made for analysis of wound area. Twelve days after, animals were euthanized and skin samples removed for histological analysis. We observed that DAP showed the best percentage of wound contraction at day 3. In the treatments using MSCs, a negative value of wound contraction was observed for the isolated MSCs, as well as a lower contraction value for the association of the MSC + DAP when compared to PBS, probably, by the increase in initial infammation after the application of stem cells, due to the fact that MSCs secrete a broad spectrum of bioactive molecules such as cytokines and growth factors that favor regeneration. Histologically, it was observed that animals of C+ showed extensive areas of necrosis, ulcers, neutrophilic infiltrate, and mineralization. Collagen deposition showed increase in MSC+DAP treatment, however vascularization remained unchanged. This is the first report using MSC and MSC+DAP as a treatment for cutaneous loxoscelism and more studies are needed to determine its use as an alternative therapy for dermonecrotic lesions caused by Loxosceles spider.

Este estudo teve como objetivo avaliar a eficácia das células-tronco mesenquimais (CTMs), isoladas ou associadas à dapsona (DAP), no tratamento de feridas dermonecróticas causadas pelo veneno de Loxosceles laeta. Vinte e cinco coelhos machos foram distribuídos em cinco grupos. O controle negativo recebeu água ultrapura (C-), enquanto todos os outros grupos foram injetados com 20 μg de veneno de L. laeta. Após 4 horas, cada grupo recebeu um dos seguintes tratamentos: PBS (C+), DAP, CTMs e DAP + CTMs. Os animais foram avaliados diariamente durante 12 dias, e feitos registros fotográficos para análise da ferida e no 12º dia, foram eutanasiados e, retiradas amostras de pele para análise histológica. Observou-se que a DAP apresentou o melhor percentual de contração da ferida no terceiro dia. Nos tratamentos com CTMs, observou-se uma contração negativa da ferida tanto para as CTMs isoladas, bem como a associação CTMs + DAP em relação ao PBS, possivelmente, pelo aumento da infamação inicial após a aplicação de células-tronco. Isso é devido ao fato de que as CTMs secretam um amplo espectro de moléculas bioativas como citocinas e fatores de crescimento que favorecem a regeneração. Histologicamente, observou-se que os animais de C+ apresentaram extensas áreas de necrose, úlceras, infiltrado neutrofílico, além de mineralização. Houve aumento de deposição de colágeno no tratamento CTMs + DAP, no entanto, a vascularização permaneceu inalterada. Este é o primeiro relato usando CTMs e CTMs + DAP como tratamento para loxoscelismo cutâneo e mais estudos são necessários para determinar seu uso como terapia alternativa para lesões demonecróticas causadas pela aranha Loxosceles.

Células-tronco mesenquimais para tratamento de displasia coxofemoral em cão / Mesenchymal stem cells for treatment of coxofemoral dysplasia in a dog

Background: Coxofemoral dysplasia (CFD) is the abnormal development of the hip joint, mostly affecting large breeds, and is characterized by subluxation or complete luxation of the femoral head. Among the conservative therapeutic options, cell therapies with stem cells for CFD provides potential by the countless possibilities of therapeutic application, especially those related to the chronic and/or degenerative diseases treatment, which could be a key point for the bone and joint repair. The objective was to report a bilateral CFD case in a dog, treated with intra-articular application of mesenchymal stem cells (MSC), with 0, 30, 60 and 90 days, and further evaluations. Case: A 2-year-old male Akita dog was referred to the Veterinary Hospital Harmonia (HVH) located in the city of Recife, Pernambuco, presenting clinical signs of hip pain, lameness and pelvic limbs hopping. By orthopedic examination, pain was observed at the cranial and caudal extension of the pelvic limb, and at flexion, abduction and adduction of the limb, as well as moderate muscle atrophy and presence of joint crackling. By coxofemoral radiography performed in ventrodorsal projection, it were detected bilateral femoral head subluxation, thickening of the femoral neck and the presence of intraarticular osteophytes. These findings are compatible with the degeneration caused by the presence of CFD. Laboratory tests performed such as hemogram and biochemical had no changes. Thus, the patient had intra-articular application of allogeneic MSC, derived from adipose tissue, obtained by private company. For stem cell applications, arthrocentesis of the hip joints was performed one at a time, using a 5 mL syringe and 16G needle for aspiration of 2 mL synovial fluid, for discard and application of stem cells. After aspiration, the syringe containing the MSC were fitted to the 16G needle for the implant. After the...

Biological behavior of magnesium-substituted hydroxyapatite during bone repair / Comportamento biológico de hidroxiapatita substituída com magnésio durante o reparo ósseo

The aim of this study was to analyze the biological behavior and osteogenic potential of magnesium (Mg) substituted hydroxyapatite (HA) microspheres, implanted in a critical bone defect, considering that this ion is of great clinical interest, since it is closely associated with homeostasis and bone mineralization. For the purpose of this study, 30 rats were used to compose three experimental groups: GI - bone defect filled with HA microspheres; GII - bone defect filled with HA microspheres replaced with Mg; GIII - empty bone defect; evaluated at biological points of 15 and 45 days. The histological results, at 15 days, showed, in all the groups, a discrete chronic inflammatory infiltrate; biomaterials intact and surrounded by connective tissue; and bone neoformation restricted to the borders. At 45 days, in the GI and GII groups, an inflammatory response of discrete granulomatous chronic type was observed, and in the GIII there was a scarce presence of mononuclear inflammatory cells; in GI and GII, the microspheres were seen to be either intact or fragmented, surrounded by fibrous connective tissue rich in blood vessels; and discrete bone neoformation near the edges and surrounding some microspheres. In GIII, the mineralization was limited to the borders and the remaining area was filled by fibrous connective tissue. It was concluded that the biomaterials were biocompatible and osteoconductive, and the percentage of Mg used as replacement ion in the HA did not favor a greater bone neoformation in relation to the HA without the metal.(AU)

O objetivo deste estudo foi analisar o comportamento biológico de microesferas de hidroxiapatita (HA) substituída com magnésio (Mg) durante o reparo de defeito ósseo crítico, tendo em vista que este íon é de grande interesse clínico, pois está intimamente associado à homeostasia e à mineralização óssea. Para tanto, utilizou-se 30 ratos para compor três grupos experimentais: GI - defeito ósseo preenchido com microesferas de HA; GII - defeito ósseo preenchido com microesferas de HA substituída com Mg; GIII (controle) - defeito ósseo vazio; avaliados nos pontos biológicos de 15 e 45 dias. Os resultados histológicos evidenciaram, aos 15 dias, discreto infiltrado inflamatório crônico e neoformação óssea restrita às bordas, em todos os grupos. Nos grupos GI e GII, os biomateriais mantiveram-se íntegros e circundados por tecido conjuntivo frouxo. Aos 45 dias, notou-se resposta inflamatória do tipo crônica granulomatosa discreta nos grupos GI e GII, e no GIII presença escassa de células inflamatórias mononucleares. As microesferas implantadas no GI e GII mantiveram-se, em sua maioria, íntegras e envolvidas por tecido conjuntivo fibroso. Notou-se discreta neoformação óssea próxima às bordas e circunjacente a algumas microesferas. No GIII, a mineralização limitou-se às bordas e a área remanescente foi preenchida por tecido conjuntivo fibroso. Conclui-se que os biomateriais foram biocompatíveis, bioativos, osteocondutores e apresentaram biodegradação lenta, indicando seu grande potencial para em aplicações clínica como biomaterial de preenchimento.(AU)

Effect of S53P4 bioactive glass and low-level laser therapy on calvarial bone repair in rats submitted to zoledronic acid therapy

ABSTRACT Purpose To evaluate the influence of bioactive glass and photobiomodulation therapy (PBMT) in calvarial bone repair process in rats submitted to zoledronic acid therapy. Methods Twenty-four rats were selected and treated with the dose of 0.035 mg/kg of zoledronic acid every two weeks, totalizing eight weeks, to induce osteonecrosis. After the drug therapy, surgical procedure was performed to create 5-mm diameter parietal bone defects in the calvarial region. The rats were then randomly assigned to groups according to the following treatments: AZC: control group, treated with blood clot; AZBIO: bone defect filled with bioactive glass; AZL: treated with blood clot and submitted to PBMT; and AZBIOL: treated with bioactive glass S53P4 and submitted to PBMT. Tissue samples were collected and submitted to histomorphometric analysis after 14 and 28 days. Results At 14 days, bone neoformation in the AZBIO (52.15 ± 9.77) and AZBIOL (49.77 ± 13.58) groups presented higher values (p ≤ 0.001) compared to the AZC (23.35 ± 10.15) and AZL groups (23.32 ± 8.75). At 28 days, AZBIO (80.24 ± 5.41)still presented significant higher bone recovery values when compared to AZC (59.59 ± 16.92)and AZL (45.25 ± 5.41) groups (p = 0.048). In the 28-day period, the AZBIOL group didn't show statistically significant difference with the other groups (71.79 ± 29.38). Conclusions The bioactive glass is an effective protocol to stimulate bone neoformation in critical defects surgically created in rats with drug induced osteonecrosis, in the studied periods of 14 and 28 days.

Correlation of serum acute-phase proteins with bone repair in rabbits (Oryctolagus cuniculus) submitted to partial radio ostectomy / Correlação do proteinograma sérico com a reparação óssea em coelhos (Oryctolagus cuniculus) submetidos à ostectomia parcial do rádio

Bone trauma triggers an acute inflammatory response, which can alter the serum concentration of acute-phase proteins (PFA). We aimed to evaluate the effectiveness of PFA measurement as a laboratory biomarker for inflammation related to bone regeneration. A partial ostectomy of the right radius was performed on 22 young male rabbits. The complete blood count, albumin, ceruloplasmin, haptoglobin, C-reactive protein, and transferrin levels were recorded and correlated with the radiographic evolution of bone healing. Statistically the best correlations with the inflammatory process and radiological findings were reported with haptoglobin and transferrin compared to the other measured PFAs. Haptoglobin and transferrin showed a maximum peak 24 and 36 hours after surgery, respectively. Transferrin displayed signs of decrease in the first 6 hours after surgery, in advance of the leukocyte response. The measurement of acute-phase proteins proved to be viable, considering the conditions in which the present study was carried out. Among all variables studied, haptoglobin and transferrin showed best correlation with the inflammatory process of bone healing. Additional studies are needed to determine the sensitivity of acute-phase proteins as predictors of complications in the treatment of fractures.(AU)

Os traumas ósseos desencadeiam resposta inflamatória aguda e consequentemente alteram a concentração sérica das proteínas de fase aguda (PFA), podendo essas representarem um parâmetro para avaliação da evolução do processo inflamatório relacionado à cicatrização óssea, assim como complicações. Objetivou-se avaliar a inter-relação da mensuração de PFAs com a repação óssea em coelhos submetidos à ostectomia parcial do rádio. Foram utilizados 22 coelhos, machos, jovens (160 a 180 dias) e peso médio (3,8 ± 0,3). Para acompanhamento da evolução do processo inflamatório foram realizados hemograma completo e mensuração de albumina, ceruloplasmina, haptoglobina, proteína C reativa e transferrina, além do acompanhamento radiológico. Foi observado a melhor correlação da haptoglobina e da transferrina junto ao processo inflamatório e achados radiológicos frente às demais PFAs mensuradas. A haptoglobina apresentou pico máximo 24 horas do pós-operatório e a transferrina após 36 horas, entretanto, essa última já mostrou indícios de diminuição nas primeiras 6 horas do pós-cirúrgico, antecipadamente à resposta leucocitária. Nas condições em que o presente estudo foi realizado, a mensuração das proteínas de fase aguda mostrou-se factível. Das proteínas estudadas, a haptoglobina e transferrina foram as que mostraram maior correlação com o processo inflamatório da cicatrização óssea. Estudos adicionais são necessários para determinar a sensibilidade das proteínas de fase aguda como previsores de complicações do tratamento das fraturas.(AU)

A castor oil plant (Ricinus communis)-derived implant improves the biomechanical properties of noncritical bone defects

Purpose The biomechanical properties of the polyurethanes implant material derived from castor oil plant (Ricinus communis) were evaluated in a noncritical bone defect model in rat tibia. Methods After three weeks of the implant application, the tibias were tested by means of the biomechanical three-point flexion test and resistance, rigidity, energy at maximum load and maximum energy were evaluated. Nonparametric statistical analysis was performed. Results It was found that the group that received the implant behaved the same as the intact control group and also showed a significant increase in maximum load compared to the spontaneous repair group. Conclusions Our results indicate that the tibias with the implant material in a noncritical bone defect recover normal biomechanical parameters in less time than spontaneously.(AU)

Platelet-concentrated and platelet poor-plasma promote different pattern on immunohistochemical expression of TGF-β1, however they impairs the osteoneogensis in calvarial defects treated with autograft due suppression of osteocalcin

ABSTRACT Purpose Herein we evaluated the effects of platelet concentrate (PC) and platelet-poor plasma (PPP) on bone repair using noncritical defects in the calvaria of rabbits and compared them to the presence of TGF-β1 and osteocalcin on reparative sites. Methods Five noncritical defects of 8.7 mm in diameter were created on the calvaria of 15 animals. Each defect was treated differently, using autograft (ABG), ABG associated with PC (ABG + PC), ABG with PPP (ABG + PPP), isolated PPP, and blood clot (control). The animals were submitted to euthanasia on the second, fourth and sixth week post-surgery. Results The defects that received ABG+PC or PPP demonstrated lower bone formation when compared to specimens that received ABG in the same period. These results coincided to significant higher immunopositivity for TGF-β1 for specimens that received PC, and lower presence of cytokine in the group PPP. However, either higher or lower presence of TGF-β1 were also correlated to lower presence of osteocalcin. Likewise, these results were similar to findings in specimens treated only with PPP when compared to control. Conclusions PC and PPP were not effective when applied in association with ABG. Similarly, isolated use of PPP was not beneficial in optimizing the bone repair.

Utilização de curativo a vácuo de baixo custo para cicatrização de fratura de casco com ruptura de cavidade celomática em um Chelonia carbonaria / Use of cost-effective vacuum-assisted closure technique for shell fracture Repair and coelomic cavity rupture healing in a Chelonia carbonaria

Background: The vacuum-assisted closure (VAC) therapy system has been used as a noninvasive wound managementtechnique for shell damage in Chelonians. These animals are excellent candidates for VAC therapy because of their uniqueshell anatomy consists of dermal bones, which make bandage placement easier. Beyond that, they are suited for this technique behaviorally, because they are not inclined to remove the vacuum system intentionally. Considering the possibilityof Testudines shell repair with the use of less invasive techniques, that result no additional dermal bone lesions, the objective of the present study is to describe the adaptation of a vacuum dressing protocol using low-cost and easily accessiblematerials for post-traumatic shell healing of a specimen of Chelonoidis carbonaria.Case: A specimen of tortoise (Chelonoidis carbonaria), a male, weighing 630 g, approximately 3-year-old, was received atthe Veterinary Hospital - Wild Animals Sector in the Federal University of Pará (UFPA) after of being run over by a vehicle.On physical examination, fractures of the dermal plaques and underlying bone structures were found, with rupture of thecoelomic cavity. In addition, there was exposure and incarceration of an intestinal loop, with the presence of bleeding.According to the findings of the physical screening examination, the patient’s prognosis was defined as good, as describedin the literature that specifically focused on chelonian shell injuries. The animal was sent to the diagnostic imaging sector.Then, drug therapy was provided for pain control, vitamins were administered for nutritional support, and antibiotics andanti-inflammatory drugs were instituted. For the closure of the shell and coelomic cavity, a bandage was used with theVAC therapy system adapted as described for Chelonians in previous reports. After a complete osteosynthesis and closureof the coelomic cavity, repair of the integumentary component of the shell was...

Utilização de curativo a vácuo de baixo custo para cicatrização de fratura de casco com ruptura de cavidade celomática em um Chelonia carbonaria / Use of cost-effective vacuum-assisted closure technique for shell fracture Repair and coelomic cavity rupture healing in a Chelonia carbonaria

Background: The vacuum-assisted closure (VAC) therapy system has been used as a noninvasive wound managementtechnique for shell damage in Chelonians. These animals are excellent candidates for VAC therapy because of their uniqueshell anatomy consists of dermal bones, which make bandage placement easier. Beyond that, they are suited for this technique behaviorally, because they are not inclined to remove the vacuum system intentionally. Considering the possibilityof Testudines shell repair with the use of less invasive techniques, that result no additional dermal bone lesions, the objective of the present study is to describe the adaptation of a vacuum dressing protocol using low-cost and easily accessiblematerials for post-traumatic shell healing of a specimen of Chelonoidis carbonaria.Case: A specimen of tortoise (Chelonoidis carbonaria), a male, weighing 630 g, approximately 3-year-old, was received atthe Veterinary Hospital - Wild Animals Sector in the Federal University of Pará (UFPA) after of being run over by a vehicle.On physical examination, fractures of the dermal plaques and underlying bone structures were found, with rupture of thecoelomic cavity. In addition, there was exposure and incarceration of an intestinal loop, with the presence of bleeding.According to the findings of the physical screening examination, the patients prognosis was defined as good, as describedin the literature that specifically focused on chelonian shell injuries. The animal was sent to the diagnostic imaging sector.Then, drug therapy was provided for pain control, vitamins were administered for nutritional support, and antibiotics andanti-inflammatory drugs were instituted. For the closure of the shell and coelomic cavity, a bandage was used with theVAC therapy system adapted as described for Chelonians in previous reports. After a complete osteosynthesis and closureof the coelomic cavity, repair of the integumentary component of the shell was...(AU)