Valuation of angiogenesis in bovine xenografts implanted in intracorporal sites of rabbits as models of in-vivo bioreactors / Avaliação da angiogênese em xenoenxertos bovinos implantados em sítios intracorpóreos de coelhos como modelos de biorreatores in vivo

The aim of this study was to evaluate neovascularization of bovine xenografts implanted in intracorporeal sites of rabbits (bioreactors). 30 rabbits were used, divided into 6 groups, according to the evaluation time (7, 15, 30, 45, and 60 days); each animal received xenogenic implants in 3 different intracorporeal sites (A1 - omentum bag; A2 - intermuscular space of quadriceps femoris; A3 - subperiosteal of ilium bone). Histological assessments graded the presence of angiogenesis, the number of inflammatory cells, newly formed bone tissue, and the presence of giant cells. Histological analyses showed intense angiogenesis in all implanted xenografts. Presence of inflammatory infiltrate and giant cells at the A1 implant site and presence of bone neoformation at the A3 implant site were noted. Degeneration of implants and formation of a fibrous capsule were noted. When comparing the interaction of the site with the days of evaluation, statistical analysis showed a significant difference (p≤0.05) in any time of neovascularization analysis. The vascular endothelial growth factor (VEGF) and inflammatory cells of the omentum in its structure, may have contributed to the greater presence of neovessels and inflammatory cells, a fact that may indicate functionality as a possible bone substitute.(AU)

O objetivo deste estudo foi avaliar a neovascularização de xenoenxertos bovinos implantados em sítios intracorpóreos de coelhos (biorreatores). Foram utilizados 30 coelhos, os quais foram divididos em seis grupos, de acordo com o tempo de avaliação (sete, 15, 30, 45 e 60 dias); cada animal recebeu implantes xenogênicos em três diferentes sítios intracorpóreos (A1 - bolsa de omento; A2 - espaço intermuscular do quadríceps femoral; A3 - subperiosteal do osso ílio). Avaliações histológicas classificaram a presença de angiogênese, o número de células inflamatórias, de tecido ósseo neoformado e a presença de células gigantes. As análises histológicas mostraram intensa angiogênese em todos os xenoenxertos implantados. Observou-se presença de infiltrado inflamatório e células gigantes no local do implante A1 e presença de neoformação óssea no local do implante A3. Ao mesmo tempo, a degeneração dos implantes e a formação de uma cápsula fibrosa foram observadas. Ao comparar a interação do local com os dias de avaliação, a análise estatística mostrou diferença significativa (P≤0,05) em qualquer momento da análise de neovascularização. O fator de crescimento endotelial vascular (VEGF) e as células inflamatórias do omento em sua estrutura podem ter contribuído para a maior presença de neovasos e células inflamatórias, fato que pode indicar funcionalidade como possível substituto ósseo.(AU)

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)

Hérnia inguinal com encarceramento esplênico em cão macho / Inguinal hernia with splenic incarceration in a male dog

Background: Hernias are changes with the displacement of organs from their normal anatomical location to a newly formedcavity, which can cause pain and dysfunction of the affected organ. The diagnosis can be obtained by palpation or by ultrasound.The treatment of choice is surgical and vision to promote the return of the organ to its normal anatomical position and theclosure of the hernial ring. When affixing the edges of the hernial ring is not possible, alternative techniques such as the useof biological or synthetic membranes should be sought. The aim of the present study is to report an atypical case of inguinalhernia with splenic incarceration, in which splenectomy and herniorrhaphy with a bovine phrenic center were performed.Case: An 8-year-old large mestizo male dog was referred to the Veterinary Hospital of Uberaba complaining of the appearance of a mass in the inguinal region that increased significantly in the last 15 days. On physical examination, there was anincrease in volume in the left inguinal region, irreducible and great pain sensitivity in the region. The hemogram showednormochromic normocytic anemia, hyperproteinemia and thrombocytopenia. No changes were observed in the biochemicalanalyzes. Urinalysis revealed the presence of protein and traces of occult blood. Ultrasound showed an enlarged spleen insidethe hernial sac, closing the diagnosis of inguinal hernia. The animal underwent a herniorrhaphy procedure associated with theuse of a biological membrane from a bovine phrenic center and splenectomy. In addition, contralateral inguinal hernia wasobserved. The animal remained hospitalized and under observation for three days. On return, after five days, the guardian..

Hérnia inguinal com encarceramento esplênico em cão macho / Inguinal hernia with splenic incarceration in a male dog

Background: Hernias are changes with the displacement of organs from their normal anatomical location to a newly formedcavity, which can cause pain and dysfunction of the affected organ. The diagnosis can be obtained by palpation or by ultrasound.The treatment of choice is surgical and vision to promote the return of the organ to its normal anatomical position and theclosure of the hernial ring. When affixing the edges of the hernial ring is not possible, alternative techniques such as the useof biological or synthetic membranes should be sought. The aim of the present study is to report an atypical case of inguinalhernia with splenic incarceration, in which splenectomy and herniorrhaphy with a bovine phrenic center were performed.Case: An 8-year-old large mestizo male dog was referred to the Veterinary Hospital of Uberaba complaining of the appearance of a mass in the inguinal region that increased significantly in the last 15 days. On physical examination, there was anincrease in volume in the left inguinal region, irreducible and great pain sensitivity in the region. The hemogram showednormochromic normocytic anemia, hyperproteinemia and thrombocytopenia. No changes were observed in the biochemicalanalyzes. Urinalysis revealed the presence of protein and traces of occult blood. Ultrasound showed an enlarged spleen insidethe hernial sac, closing the diagnosis of inguinal hernia. The animal underwent a herniorrhaphy procedure associated with theuse of a biological membrane from a bovine phrenic center and splenectomy. In addition, contralateral inguinal hernia wasobserved. The animal remained hospitalized and under observation for three days. On return, after five days, the guardian..(AU)

Tratamento de estenose pélvica em gato com enxerto heterólogo e colectomia subtotal / Treatment of pelvic stenosis with heterologous graft and subtotal colectomy in a cat

Background: The management of malunion of pelvic fracture and its complications may require from conservative tosurgical methods, depending on the severity and temporal evolution. Thus, the aim of this present report is to describe thetreatments adopted in a cat with severe pelvic stenosis.Case: An approximately 3-year-old neutered male crossbreed cat, weighing 3 kg, was presented due to difficulty in defecation in the previous eight months. According to its tutor, the cat was adopted one year earlier, with a history of pelvicfracture due to a run over, which had been treated conservatively. The tutor also mentioned that since the appearance ofdyschezia, the cat had only been treated with enemas, but without success. In abdominal palpation, there was presence ofpain and a mass of firm content in descending colon topography. The radiographic examination of the pelvis presentedan exuberant bone callus, characterizing an old fracture, a consolidation with change of bone axis in the right ischium,together with megacolon and fecaloma. It was initially decided that a liquid glycerin-based enema would be performed,in conjunction with clinical treatment with administration of cisapride, dimethicone and lactulose. Although the medicaltreatment initially helped improve the clinical picture, the cat presented fecaloma two months later. Surgical treatment wasthen performed, in which distraction of the pubic symphysis with use of a heterologous cortical bone graft (canine tibiastored in glycerin 98%) was performed, as the tutor was not favorable to colectomy as the first option. However, after onemonth of intervention, despite good evolution, the animal again showed signs of dyschezia. At this point the tutor agreedto colectomy, which was subtotal with preservation of the ileocolic valve.Discussion: The...

Tratamento de estenose pélvica em gato com enxerto heterólogo e colectomia subtotal / Treatment of pelvic stenosis with heterologous graft and subtotal colectomy in a cat

Background: The management of malunion of pelvic fracture and its complications may require from conservative tosurgical methods, depending on the severity and temporal evolution. Thus, the aim of this present report is to describe thetreatments adopted in a cat with severe pelvic stenosis.Case: An approximately 3-year-old neutered male crossbreed cat, weighing 3 kg, was presented due to difficulty in defecation in the previous eight months. According to its tutor, the cat was adopted one year earlier, with a history of pelvicfracture due to a run over, which had been treated conservatively. The tutor also mentioned that since the appearance ofdyschezia, the cat had only been treated with enemas, but without success. In abdominal palpation, there was presence ofpain and a mass of firm content in descending colon topography. The radiographic examination of the pelvis presentedan exuberant bone callus, characterizing an old fracture, a consolidation with change of bone axis in the right ischium,together with megacolon and fecaloma. It was initially decided that a liquid glycerin-based enema would be performed,in conjunction with clinical treatment with administration of cisapride, dimethicone and lactulose. Although the medicaltreatment initially helped improve the clinical picture, the cat presented fecaloma two months later. Surgical treatment wasthen performed, in which distraction of the pubic symphysis with use of a heterologous cortical bone graft (canine tibiastored in glycerin 98%) was performed, as the tutor was not favorable to colectomy as the first option. However, after onemonth of intervention, despite good evolution, the animal again showed signs of dyschezia. At this point the tutor agreedto colectomy, which was subtotal with preservation of the ileocolic valve.Discussion: The...(AU)

Action of a deproteinized xenogenic biomaterial in the process of bone repair in rats submitted to inhalation of cigarette smoke

Purpose: To investigate if the inorganic bovine bone matrix changes the bone formation in rats submitted to inhalation of cigarette smoke. Methods: Twenty Wistar rats were divided into two groups: Cigarette Clot Group (CCG), which in the inhalation chamber received the smoke of 10 cigarettes, 3 times a day, 10 minutes, for 30 days and had the surgical cavity filled by clot; Cigarette Biomaterial Group (CBG), submitted to the same inhalation technique but with the cavity filled by biomaterial. Results: In CCG there was a significant difference of new bone tissue in the analyzed periods (15 and 45 days), and in 15 days, there was 4.8 ± 0.42 of bone formed and 11.73 ± 0.59 (p <0.05) in 45 days. The CBG also showed a significant difference between the periods of 15 to 45 days, being respectively 6.16 ± 0.30 and 11.60 ± 0.61. However, when the groups were compared, within the same analyzed periods, a significant difference was observed only in the period of 15 days, with the new bone percentage being greater in the CBG. Conclusion: The bone matrix acted as an osteoinductive biomaterial, biocompatible and aided in the repair process, mainly in the initial period of recovery.(AU)

Orthotopic tumorgrafts in nude mice as a model to evaluate calcitriol effects in breast cancer / Modelo de enxerto tumoral ortotópico em camundongos para avaliar os efeitos do calcitriol em câncer de mama

Calcitriol antiproliferative effects were observed in xenografts of breast cancer cell lines, however they were not yet investigated in tumorgrafts, consisting of freshly collected breast cancer samples xenografted into animals. Objectives To establish a tumorgraft model, from freshly collected breast cancer samples, which were directly implanted in nude mice, to study calcitriol effects. Methods Breast cancer samples collected from 12 patients were orthotopically implanted into nude mice. Animals were treated with weekly intratumoral injections of calcitriol 3 g/Kg, which was previously shown to induce peak serum calcitriol levels in the predicted therapeutic range. Results Success engraftment rate was 25%. Tumorgrafts were established from aggressive (HER2 positive or histological grade 3) highly proliferative samples and original tumor characteristics were preserved. Calcitriol highly induced its target gene, CYP24A1, indicating that the genomic vitamin D pathway is active in tumorgrafts. However, no differences in the expression of proliferation and apoptosis markers (BrdU incorporation, Ki67, CDKN1A, CDKN1B, BCL2 expression) were observed in these highly proliferative tumor samples.Conclusions Tumorgrafts seem a promising model to explore other calcitriol doses and regimens, considering the heterogeneity of the disease and microenvironment interactions.(AU)

Os efeitos antiproliferativos de calcitriol foram observados em xenotransplantes de linhagens celulares de câncer de mama, entretanto, não foram ainda investigados em enxertos tumorais, consistindo de implantes em animais de amostras de câncer de mama recém-coletadas.Objetivos Estabelecer modelo de enxerto tumoral, a partir de amostra de câncer de mama recém-coletada e diretamente implantada em camundongos nude, para estudar o efeito do calcitriol. Métodos Amostras de câncer de mama de 12 pacientes foram implantadas ortotopicamente em camundongos nude. Os animais foram tratados com injeção intratumoral semanal de calcitriol 3 g/Kg, a qual foi previamente associada com indução de pico sérico de calcitriol dentro do intervalo de nível terapêutico. Resultados A taxa de sucesso de pega do enxerto foi de 25%. Os enxertos tumorais foram estabelecidos de tumores agressivos com alta taxa de proliferação (HER2 positivo ou grau histológico 3) e as características do tumor original foram preservadas. O calcitriol induziu fortemente a expressão do gene alvo, CYP24A1, indicando que a via genômica da vitamina D está ativa nos enxertos tumorais, entretanto, não se observou diferenças na expressão de marcadores de proliferação e apoptose (incorporação de BrdU, expressão de Ki67, CDKN1A, CDKN1B e BCL2) nestas amostras altamente proliferativas.Conclusões Os enxertos tumorais parecem ser um modelo promissor para explorar outros esquemas e doses de calcitriol, considerando a heterogeneidade da doença e interações com o microambiente.(AU)

Avaliação morfofuncional do enxerto de túnica albugínea suína na cistoplastia em ratos / Morpho-fuctional evaluation of porcine tunica albuginea as a graft for cystoplasty in rats

O objetivo deste trabalho é avaliar o uso da túnica albugínea suína na cistoplastia em ratos, avaliando funcionalidade, capacidade de reparação do órgão e possibilidades de complicações. Foram selecionados 30 ratos Wistar, machos, de seis meses de idade, divididos em: um grupo teste (TA), em que os animais receberam o enxerto de túnica albugínea suína após a cistectomia parcial e um grupo controle (C), em que os animais sofreram somente a cistectomia parcial. Os animais pertencentes a ambos os grupos foram divididos igualmente em subgrupos de cinco animais cada, que sofreram eutanásia em sete, 28 e 42 dias de pós-operatório. Foi realizada uma análise macroscópica e, posteriormente, uma análise histopatológica da região da ferida cirúrgica. Aos sete e 28 dias, os animais pertencentes ao grupo C e ao grupo TA apresentaram urotelização, regeneração da lâmina própria e da musculatura, porém o grupo TA apresentou menores sinais inflamatórios e maior organização tecidual, principalmente com relação à formação das fibras musculares. Aos 42 dias de pós-operatório, ambos os grupos já apresentavam características histológicas normais. Concluiu-se que o enxerto de túnica albugínea suína obteve sucesso na regeneração da bexiga de ratos, mantendo a funcionalidade do órgão, sem rejeição, e favorecendo a migração celular.(AU)

The aim of this study is to evaluate porcine tunica albuginea as a graft for cystoplasty in rats, regarding bladder function, capacity and possible complications. 30 male Wistar rats with six monthes of age have been selected and separated into two different groups: A test group (TA) in which the animals received a tunica albuginea graft after partial cystectomy and a control group (C) in which partial cystectomy was performed, followed by bladder suture. In each group the animals were euthanized at seven, 28 and 42 days after surgery. Macroscopic and Histological analysis have been performed. At seven and 28 days after surgery the samples from both groups had urothelial lining upon a lamina propria and smooth muscle fibers in regeneration process. However, the TA group showed less inflammatory signs and more organized structure, mainly regarding the smooth muscle formation. At 42 days after surgery all groups showed a bladder wall structure qualitatively identical to the normal tissue. We could conclude that tunica albuginea graft is able to maintain bladder function and support cellular migration without any kind of rejection.(AU)

Avaliação morfofuncional do enxerto de túnica albugínea suína na cistoplastia em ratos / Morpho-fuctional evaluation of porcine tunica albuginea as a graft for cystoplasty in rats

O objetivo deste trabalho é avaliar o uso da túnica albugínea suína na cistoplastia em ratos, avaliando funcionalidade, capacidade de reparação do órgão e possibilidades de complicações. Foram selecionados 30 ratos Wistar, machos, de seis meses de idade, divididos em: um grupo teste (TA), em que os animais receberam o enxerto de túnica albugínea suína após a cistectomia parcial e um grupo controle (C), em que os animais sofreram somente a cistectomia parcial. Os animais pertencentes a ambos os grupos foram divididos igualmente em subgrupos de cinco animais cada, que sofreram eutanásia em sete, 28 e 42 dias de pós-operatório. Foi realizada uma análise macroscópica e, posteriormente, uma análise histopatológica da região da ferida cirúrgica. Aos sete e 28 dias, os animais pertencentes ao grupo C e ao grupo TA apresentaram urotelização, regeneração da lâmina própria e da musculatura, porém o grupo TA apresentou menores sinais inflamatórios e maior organização tecidual, principalmente com relação à formação das fibras musculares. Aos 42 dias de pós-operatório, ambos os grupos já apresentavam características histológicas normais. Concluiu-se que o enxerto de túnica albugínea suína obteve sucesso na regeneração da bexiga de ratos, mantendo a funcionalidade do órgão, sem rejeição, e favorecendo a migração celular.(AU)

The aim of this study is to evaluate porcine tunica albuginea as a graft for cystoplasty in rats, regarding bladder function, capacity and possible complications. 30 male Wistar rats with six monthes of age have been selected and separated into two different groups: A test group (TA) in which the animals received a tunica albuginea graft after partial cystectomy and a control group (C) in which partial cystectomy was performed, followed by bladder suture. In each group the animals were euthanized at seven, 28 and 42 days after surgery. Macroscopic and Histological analysis have been performed. At seven and 28 days after surgery the samples from both groups had urothelial lining upon a lamina propria and smooth muscle fibers in regeneration process. However, the TA group showed less inflammatory signs and more organized structure, mainly regarding the smooth muscle formation. At 42 days after surgery all groups showed a bladder wall structure qualitatively identical to the normal tissue. We could conclude that tunica albuginea graft is able to maintain bladder function and support cellular migration without any kind of rejection.(AU)

Aspecto radiológico de heteroenxerto ósseo cortical fragmentado na reparação de falhas ósseas em coelhos / Radiologic aspects of fragmented cortical bone heterograft in bone defect repair in rabbits

Foi realizada falha segmentar de 6mm na região metafisária da tíbia de 12 coelhos,sendo utilizado enxerto ósseo cotical heterólogo fragmentado conservado em glicerina (98 por cento), para a sua reconstrução. O enxerto foi depositado no leito receptor e a integração deste foi avaliada radiologicamente por 20, 40 e 60 dias. Houve incorporação gradativa, em relação ao tempo, do enxerto no leito receptor, em 100 por cento dos casos. O uso de heteroenxerto ósseo cortical fragmentado e conservado em glicerina a 98 por cento promove a reparação das falhas ósseas, sem sinais de infecção ou rejeição, podendo ser utilizado como substituto ósseo na medicina veterinária [...](AU)

It was realized a 6mm of segmental defect at the metaphyseal region of the tibia of 12 rabbits and fragmented heterolog cortical bone graft conserved in glycerin (98 percent) was used to the reconstruction. The graft was placed in the receptor bed and its integration was evaluated by radiological exam after 20, 40, and 60 days. There was gradative graft incorporation, by the time, in the receptor bed, in 100 percent of the cases. The use of fragmented cortical bone heterograf conserved in glycerin 98 percent promotes bone defect reparation without signs of infection and can be used like osseous substitute in the veterinary medicine [...](AU)