Bovine tunica albuginea conserved in honey as xenograft for cystoplasty in rats / Túnica albugínea bovina conservada em mel como xenoenxerto na cistoplastia em ratos

Urinary bladder damages leading to few viable bladder tissue available might demand a challenging reconstructive surgery. In this context, biomaterials are valid alternatives for bladder reconstruction. This study evaluated the bovine tunica albuginea fragment as graft material for cystoplasty in rats and honey-preserved implant viability. Thirty Wistar rats were assigned to two groups: (1) a test group (T) with a circular 1.0-cm-diameterbovine tunica albuginea graft application in the apex region by a continuous absorbable (Polyglactin 910 5-0) suture with stitching of all bladder layers and (2) a simulation group (S) in which animals underwent only partial cystectomy. In addition, each of these groups was further divided into three subgroups according to euthanasia period on post-surgery day 7, 15 and 30. Two animals had self-limiting hematuria at postsurgical period. At necropsy, frequent crystals and adhesion to the peritoneum were observed. At the histopathological evaluation, animals from the T group euthanized by 15th postoperative day had layers disorganization and initial muscle development, while T group rats euthanized by 30th postoperative day showed complete urothelization. Urothelization pattern was similar in both groups. Moreover, the muscular layer formation was present in both groups, but more evident in S group animals. Nevertheless, inflammatory infiltrate and neovascularization were remarkably more intense in T group rats. It might be concluded that bovine tunica albuginea graft was successful in repairing rats bladder, being a good biomaterial option in reconstructive urinary vesicle surgery.(AU)

Lesões na vesícula urinária que culminem em pouco tecido vesical viável podem demandar cirurgias reconstrutivas desafiadoras. Neste contexto, biomateriais são alternativas válidas para a reconstrução da bexiga. O objetivo deste trabalho foi avaliar a túnica albugínea bovina como material para enxerto na cistoplastia em ratos, assim como a viabilidade deste implante preservado em mel. Trinta ratos Wistar foram divididos em dois grupos: (1) um grupo teste (T), no qual os animais foram submetidos a cistectomia parcial seguida de cistoplastia com aplicação do enxerto circular com 1,0cm de diâmetro de túnica albugínea bovina na região do ápice com sutura absorvível (Poliglactina 910 5-0) em padrão contínuo englobando todas as camadas da bexiga; e (2) um grupo simulação (S), cujos ratos realizaram apenas cistectomia parcial. Além disso, cada grupo foi posteriormente dividido em três subgrupos de acordo com a data de eutanásia no dia 7, 15 ou 30 de pós-operatório. Dois animais apresentaram hematúria autolimitante no período de observação pós-operatória. Na necrópsia, notaram-se cristais frequentes e aderências entre bexiga e peritônio. Na avaliação histopatológica, animais do grupo T eutanasiados com 15 dias de pós-operatório apresentavam camadas vesicais desorganizadas e formação de musculatura inicial na bexiga, enquanto aqueles eutanasiados com 30 dias de cirurgia mostraram urotelização completa. O padrão de urotelização foi semelhante nos dois grupos. Além disso, a formação da camada muscular esteve presente em ambos os grupos, porém mais evidente nos animais do grupo S. No entanto, o infiltrado inflamatório bem como a neovascularização foram notavelmente mais intensos nos ratos do grupo T. Pode-se concluir que o enxerto de túnica albugínea bovina foi bem sucedido no reparo da vesícula urinária de ratos, demonstrando ser uma boa opção de biomaterial para cirurgias reconstrutivas da vesícula urinária.(AU)

Combination of heterologous fibrin sealant and bioengineered human embryonic stem cells to improve regeneration following autogenous sciatic nerve grafting repair

Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Methods Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F +T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. Results The experiments indicated that sensory function improved when transgenic hESCs were used. The regeneration of sensory fibers indeed led to increased reflexes, upon stimulation of the paw ipsilateral to the lesion, as seen by von-Frey evaluation, which was supported by immunohistochemistry. Conclusions Overall, the present data demonstrated that transgenic embryonic stem cells, engineered to overexpress FGF-2 in an inducible fashion, could be employed to support regeneration aiming at the recovery of both motor and sensory functions.(AU)

Regeneração tecidual guiada no tratamento de defeito ósseo interproximal - relato de caso / Guided tissue regeneration in the treatment of interproximal bone defect - case report

As lesões ósseas têm a regeneração tecidual guiada (RTG) como uma possibilidade de tratamento, dependendo da morfologia do defeito. Esse procedimento visa selecionar células específicas usando uma membrana para a sua proliferação na área lesada. Entretanto, a regeneração completa do defeito pode não ser obtida, sendo a eliminação da doença o único resultado. O objetivo deste caso clínico foi avaliar o tratamento de um defeito interproximal, de duas paredes, pela técnica da RTG. Paciente GWS, 22 anos compareceu à clínica de Periodontia do SIOMS, queixando-se de sangramento gengival nos dentes 45 e 46. Após os exames clínico e radiográfico, verificou-se a presença de perda óssea interproximal nos referidos dentes, com profundidade de sondagem (PS) de 9mm e sangramento a sondagem (SS). Elaborou-se o plano de tratamento e seguiu-se tratamento periodontal não-cirúrgico. Sem sucesso na eliminação do problema, procedeu-se a RTG da área. A técnica realizada foi uma incisão intrassulcular, descolamento de um retalho total, debridamento, descontaminação química da raiz, inserção de um enxerto ósseo e de uma membrana absorvível xenógenos, reposicionamento do retalho e sutura. Fez-se o controle a cada 30 dias e, após 12 meses, a região demonstrou ausência de SS, redução da PS e aumento do nível clínico de inserção, porém, não viu-se a completa regeneração do osso interproximal. Concluiu-se que a eliminação da atividade da doença periodontal pode ser um benefício obtido na RTG sem a visualização da total regeneração óssea

Depending on the morphology of bone lesions guided tissue regeneration (GTR) is an option of treatment. This procedure aims at selecting specific cells, using a membrane for its proliferation in the injured area. However, complete regeneration of the defect may not be achieved, and in this case extinguish of the disease is the only result. The objective of the present study was to evaluate the clinical treatment of an interproximal two wall defect, using GTR technique. The patient GWS, 22 years old, attended to SIOMSÆ clinic of Periodontics, complaining of gingival bleeding on teeth 45 and 46. After clinical and radiographic examinations, was verified the presence of interproximal bone loss on those teeth with probing depth (PD) of 9mm and bleeding on probing (BOP). The treatment plan was prepared and a non-surgical periodontal treatment was adopted. This approach wasn´t able to eliminate the problem, GTR was performed in the area.Was performed an intrasulcular incision, followed by total detachment of a flap, debridement, chemical decontamination of the root, insertion of xenogenic bone graft and an absorbable membrane, flap repositioning, and suturing. The control was performed every 30 days, and after 12 months, the region presented absence of BOP, PD reduction and increased clinical attachment level. However it was not observed a complete regeneration of interproximal bone. It was concluded that the elimination of periodontal disease activity may be a benefit of GTR but without total bone regeneration