Autologous and homologous skin grafts treated with platelet-rich plasma (PRP): experimental study in rabbits / Enxertos cutâneos autólogos e homólogos tratados com plasma rico em plaquetas (PRP): estudo experimental em coelhos

The aim of the present study was to compare tissue repair of skin defects in rabbits submitted to autologous and homologous grafts treated or not with platelet-rich plasma (PRP). We selected nine rabbits and constituted four groups, designated as G1, in which were performed autologous graft treated with PRP; G2, autologous graft only; G3, homologous graft treated with PRP; and G4, homologous graft only. Macroscopic and histomorphometric evaluation was realized. The histomorphometric evaluation was performed by Hematoxylin/Eosin and Masson´s Trichrome staining with quantification of collagen fibers, macrophages, fibroblasts and vessels. The autologous graft treated with PRP showed positive influence on the early stage of the tissue repair process at the macroscopic evaluation, characterized by rosy color and cosmetic appearance. At the histomorphometric evaluation, there was no statistical difference in the number of macrophages and fibroblasts between the treated grafts or not with the PRP, as well as the quantification of vessels and collagen fibers. It can be concluded that PRP promotes a positive influence on the initial phase or "take" of the graft.(AU)

Objetiva-se com o presente estudo comparar a reparação tecidual de defeitos cutâneos em coelhos, submetidos a enxertos autólogos e homólogos, tratados ou não com plasma rico em plaquetas (PRP). Para isso, foram selecionados nove coelhos e constituídos quatro grupos experimentais, designados como G1, no qual foi realizado enxerto autólogo tratado com PRP; G2, enxerto autólogo; G3, enxerto homólogo tratado com PRP; e G4, enxerto homólogo. Foram realizadas avaliações macroscópica e histomorfométrica, por meio das colorações de Hematoxilina/Eosina e Tricômio de Masson, incluindo quantificação de fibras colágenas, contagem de macrófagos, fibroblastos e vasos. O uso do enxerto autólogo com PRP influenciou positivamente na fase inicial do processo de reparação tecidual à avaliação macroscópica, caracterizada por coloração rósea e de aspecto cosmético. À avaliação histomorfométrica, não houve diferença estatística quanto ao número de macrófagos e fibroblastos entre os enxertos tratados ou não com o PRP, bem como quanto às contagens de vasos e a quantificação das fibras colágenas. Conclui-se que o PRP sob a promoveu influência positiva na fase inicial ou de "pega" do enxerto autólogo.(AU)

Equine chorionic gonadotrophin improved vascularization of feline ovarian tissue xenografted into immunosuppressed mice.

The objective of this study was to evaluate effects of eCG on vascularization and development of feline ovarian tissue xenografted to immunosuppressed mice. Feline ovarian fragments (∼1 mm3) were transplanted under the renal capsule of 20 adult, ovariectomized, C57BL/6 SCID female mice. At 45 d after transplantation, 10 mice (controls) were euthanized and the remainder given 10 IU of eCG (and sacrificed 48 h later). Transplants were recovered immediately after death, fixed, sectioned, and stained with periodic acid-Schiff (PAS). Fragment volume (Cavallieri principle) and vascularization were assessed. Mean xenotransplant volume for control and treatment groups was 0.17 ±â€¯0.03 and 0.37 ±â€¯0.13 mm3, respectively (P = 0.0952); vascular volume density, 30.3 ±â€¯11.3 and 49.1 ±â€¯8.9% (P = 0.0281); surface density, 4.1 ±â€¯2.4 and 6.2 ±â€¯1.7 µm-1 (P = 0.2222); and vessel total surface, 0.63 ±â€¯0.24 µm2 and 2.28 ±â€¯1.05 µm2 (P = 0.0079). In conclusion, eCG significantly increased vascular volume density of xenotransplanted ovarian tissue and improved its development.

Estudio sobre quimerismo reverso y el efecto de la movilización de células madre de médula ósea sobre la expresión de citoquinas en un modelo experimental de trasplante de tejidos compuestos / Study on reverse chimerism and the effect of mobilization of bone marrow stem cells on the expression of cytokines in an experimental model of composite tissue transplantation

Introducción y Objetivo: Los trasplantes de tejidos compuestos sufren rechazo crónico modulado entre otros factores por citoquinas. El quimerismo reverso o quimerismo del aloinjerto se define como la repoblación del tejido trasplantado por células circulantes del receptor. Plerixafor produce la movilización de células madre de médula ósea CD34+ hacia la sangre periférica. El objetivo del estudio fue conocer los mecanismos moleculares que intervienen en el rechazo crónico y el quimerismo reverso tras la administración de plerixafor. Material y Método: Realizamos 16 trasplantes osteomusculares heterotópicos de pata posterior entre ratas Brown-Norway hembra y Wistar Lewis macho bajo inmunosupresión subterapéutica con tacrólimus. Establecimos 2 grupos de estudio según la administración postoperatoria de plerixafor. Transcurridas 9 semanas estudiamos la expresión de citoquinas y el infiltrado leucocitario en distintas localizaciones musculares, así como el grado de rechazo crónico y porcentaje de quimerismo reverso en diferentes tejidos del aloinjerto. Resultados: Encontramos diferencias estadísticas en la expresión de factor estimulante de colonias granulocíticas e interleucina 12 a nivel de los tercios medio y distal del aloinjerto, y de interleucina 6 a nivel del tercio medio del aloinjerto. La intensidad del infiltrado leucocitario fue mayor en el grupo que no recibió plerixafor. Ambos grupos desarrollaron rechazo crónico y pudimos observar la aparición de quimerismo reverso. Sin embargo no observamos diferencias significativas en el infiltrado leucocitario, el rechazo crónico ni el quimerismo reverso. Conclusiones: La movilización de células madre de médula ósea CD34+ se asoció con una menor expresión de factor estimulante de colonias granulocíticas, interleucina 6 e interleucina 12. Estos hallazgos contribuyen a elucidar los mecanismos moleculares que podrían conducir a la creación de quimeras en el aloinjerto

Background and Objective: Vascularized composite allotransplantation suffer chronic rejection modulated by cytokines. Reverse chimerism or allograft chimerism is defined as the repopulation of the transplanted tissue by circulating cells of the recipient. Plerixafor mobilizes CD34+ bone marrow stem cells to the peripheral blood. The aim of the study was to know the molecular mechanisms involved in chronic rejection and reverse chimerism after plerixafor administration. Methods: Sixteen heterotopic osteomuscular hindlimb transplants were performed between female Brown-Norway rats as donors and male Wistar Lewis rats as recipients under subtherapeutic immunosuppression with tacrolimus. Two groups were established according to the postoperative administration of plerixafor. After 9 weeks, expression of cytokines and leukocyte infiltration were studied in different muscle locations, as well as the degree of chronic rejection and percentage of reverse chimerism in different tissues of the allograft. Results: Statistical differences were found in granulocyte colony stimulating factor and interleukin 12 expression at middle and distal allograft thirds, and interleukin 6 expression at middle allograft third. The intensity of leukocyte infiltration was greater in the group that did not receive plerixafor. Both groups developed chronic rejection and the appearance of reverse chimerism could be observed. However, no significant differences were observed in leukocyte infiltration, chronic rejection or reverse chimerism. Conclusions: The mobilization of CD34+ bone marrow stem cells was associated with a lower expression of granulocytic colony stimulating factor, interleukin 6 and interleukin 12. These findings contribute to elucidate the molecular mechanisms that could lead to the creation of chimeras in the allograft

Restoration of fresh cat ovarian tissue function by autografting to subcutaneous tissue: A pilot study.

Ovarian tissue transplantation could be a valuable technique for the preservation of endangered animals. The domestic cat affords an adequate experimental model for studies aimed at wild felids due to its phylogenetic similarity. Thus, this pilot study evaluated the efficacy of cat ovarian tissue autotransplantation to a peripheral site. Three adult queens were submitted to ovariohysterectomy. The ovaries were fragmented into eight pieces; two were fixed as a control and six were transplanted to subcutaneous tissue of the dorsal neck. Grafts were monitored weekly by ultrasound and fecal samples collected daily in order to monitor estradiol levels. Grafts were recovered on Days: 7, 14, 28, 49 and 63 post-transplantation for histological analyses. One graft was maintained in one animal for 8 months. A total of 2466 ovarian follicles were analyzed: 1406 primordial and 1060 growing follicles. All animals presented antral follicles in one or more of the grafts. The percentage of morphologically normal primordial follicles was always higher than 80%, except for Day 7 transplants. Although the proportion of growing follicles increased after transplantation, there was a general decrease in the percentage of morphologically normal growing follicles from Day 7 onwards. All animals demonstrated at least three estradiol peaks during the 63-day period, and one animal exhibited estrous behaviour on three occasions. Hormonal peaks directly correlated with the visualization of antral follicles (by ultrasound and/or histology) and the observation of estrous behaviour. Long-term results on one female showed the concentration of 37.8 pg/mL of serum estradiol on Day 233 post-grafting and the female exhibited estrous behaviour on several occasions. This graft showed one antral follicle, one luteinized follicle and two preantral follicles. In conclusion, cat ovary autotransplantation to the subcutaneous tissue restored ovarian function, with hormone production and antral follicle development, over both short and long term periods. This could be a valuable technique in the evaluation of ovarian cryopreservation methods in felids. Once the technique is shown successful, it may be applied in allografts or xenografts between different feline species.

Surgical sponge associated with platelets rich plasma in skin mesh grafts and layer in rabbits (Oryctolagus cuniculus) / Esponja cirúrgica associada com plasma rico em plaquetas em enxertos cutâneos em malha e camada em coelhos (Oryctolagus cuniculus)

The aim of this study was to evaluate of the efficacy of PRP employment associated with surgical sponges to improve the integration of the graft in the recipient bed. It was held at the Veterinary Hospital UNESP, Campus of Jaboticabal - SP, a study of 64 rabbits, divided into eight groups with eight animals. The groups were divided in control with saline solution 0,9%, control with PRP both without the sponge, surgical sponge with PRP, surgical sponge without PRP, and were used mesh and layer grafts in the respective groups. The data were submitted to statistical analysis (paired t-test, Kruskal-Wallis test, with subsequent use of the multiple comparison tests of Dunn, analysis of variance (F) test, Tukey test, P< 0.05). Edema and exudate with 3 and 3 and 7 days (P= 0,03 e P= 0,0049); coloring on the 14th day (P= 0,0001); cosmetic appearance on the 7th and 14th day (P= 0,0026 and P= 0,0001); mononuclear cells (P= 0,01) and polymorphonuclear (P= 0,01); fibroblast proliferation (P= 0,01); collagenous (P= 0,05); hemorrhage (P-007); necrosis and re-epithelialization (P= 0,2928 and P= 0,1). We concluded that the use of Platelet Rich Plasma Gel on skin grafts associated with a sponge as a compressive dressing promote the skin graft survival without a previous granulation tissue.(AU)

O objetivo deste estudo foi avaliar a eficácia do PRP associado com esponjas cirúrgicas na integração do enxerto ao leito receptor. Realizou-se, no Hospital Veterinário da Unesp, Jaboticabal, SP, um estudo com 64 coelhos, separados em oito grupos, com oito animais. Os grupos foram: Gprpc (PRP, sem esponja cirúrgica, enxerto camada), Gprpce (PRP, esponja cirúrgica, enxerto camada), Gcc (solução fisiológica 0,9%, sem esponja cirúrgica, enxerto camada), Gcce (solução fisiológica 0,9%, esponjas cirúrgicas, enxerto camada), Gprpm (PRP, sem esponja cirúrgica, enxerto malha), Gprpme (PRP, esponja cirúrgica, enxerto malha), Gcm (solução fisiológica 0,9%, sem esponja cirúrgica, enxerto malha) e Gcce (solução fisiológica 0,9%, esponjas cirúrgicas, malha). Os dados foram analisados pelo teste t emparelhado, Kruskal-Wallis, análise de variância, e teste de Tukey (P<0,05). Edema e exsudato presente com três e sete dias (P=0,03 e P=0,0049); coloração cianótica no 14º dia (P=0,0001); aspecto cosmético bom no sétimo e no 14º dia (P=0,00026 e P=0,0001); presença de células mononucleares (P=0,01) e polimorfonucleares (P=0,01); proliferação de fibroblastos discreta (P=0,01); colagenização intensa (P=0,05); hemorragia discreta (P=0,007); ausência de diferença significativa em necrose e reepitelização (P=0,2928 e P=0,1). Conclui-se que o emprego do PRP gel em enxertos cutâneos associando esponjas cirúrgicas como curativo compressivo favorece sua integração ao leito receptor sem a presença prévia de tecido de granulação.(AU)

Emprego de Túnica albugínea heteróloga ovina como reforço de parede abdominal em ratos / Employment of ovine heterologous Tunic albuginea as abdominal wall reinforcement in rats

Hérnias são umas das afecções que mais acometem os pequenos e grandes animais, podendo ter origem traumática ou não. Estas afecções, geralmente, necessitam de um reparo cirúrgico o mais rápido possível, devido ao fato de suas consequências poderem levar o animal ao óbito. Alguns estudos têm avaliado o comportamento da túnica albugínea como biomaterial de enxertia para reforço de parede abdominal, obtendo resultados favoráveis. O presente trabalho tem como objetivo avaliar o comportamento do enxerto de túnica albugínea ovina na parede abdominal de ratos. Foram selecionados 30 ratos da raça Wistar, os quais foram divididos em 2 grupos de 15 animais, sendo um grupo controle (C), um grupo teste (TA), onde os animais receberam reforço de parede abdominal com túnica albugínea ovina. Cada grupo foi dividido em três subgrupos contendo cinco animais, que foram submetidos à eutanásia nos dias 7, 21 e 42. O material coletado foi submetido a análises macroscópicas e histopatológicas a fim de afirmar a aplicabilidade do material e propor a utilização da túnica albugínea heteróloga como material de enxertia para a reconstrução da parede abdominal. Nos animais do grupo TA observou-se maior infiltrado inflamatório, neovascularização, deposição de colágeno e fibrose do que nos animais do grupo controle, concluindo assim que a túnica albugínea ovina é um biomaterial que funciona como substrato e promove uma precocidade da cicatrização de parede abdominal de ratos.

Hernias are one of the infections that most affect small and large animals, and may have traumatic origin or not. These conditions usually require a surgical repair as soon as possible, due to the fact that its consequences can lead the animal to death. Some studies have evaluated the behavior of the Tunica albuginea as a biomaterial for grafting abdominal wall reinforcement, obtaining favorable results. This study aims to evaluate the ovine Tunica albuginea graft behavior in the abdominal wall of rats. We selected 30 Wistar rats, which were divided into 2 groups of 15 rats, with a control group (C) and a test group (TA) where the rats received abdominal wall reinforcement with ovine Tunica albuginea. Each group was divided into three subgroups with five rats that were sacrificed on days 7, 21 and 42. The collected material was submitted to macroscopic and histopathological analysis to affirm the suitability of the material and propose the use of heterologous Tunica albuginea as grafting material for the reconstruction of the abdominal wall. In the TA group there was a higher inflammatory infiltration, neovascularization and collagen deposition and fibrosis than in group control, thus concluding that the ovine Tunica albuginea is a biomaterial that acts as substrate and promotes precocity of the abdominal wall healing of rats.

Production of sperm from porcine fetal testicular tissue after cryopreservation and grafting into nude mice.

A major goal of testicular xenografting is to salvage germ cells from immature animals that cannot be used for reproduction and generate their offspring. In this study, we investigated whether porcine fetal testicular tissue would acquire the ability to produce sperm with full developmental competence after they had been cryopreserved and grafted into nude mice. Testicular fragments from fetuses at 35, 55 and 90 days postartificial insemination (dpi) were vitrified and stored in liquid nitrogen. Immediately after warming, testicular fragments at each fetal stage were transplanted under the back skin of castrated nude mice (Crlj:CD1-Foxn1nu) (35-, 55- and 90-dpi groups, respectively) (day 0 = grafting). Before grafting, the testicular fragments contained seminiferous cords consisting of only gonocytes and Sertoli cells. Histological analyses of the testicular grafts revealed that the differentiation of seminiferous tubules was largely dependent on the time after grafting, and not on donor age. On day 180 in each group, 10-20% of the total number of tubule/cord cross-sections examined had germ cells that had progressed beyond the spermatogonial stage. Fewer than 5% of tubule cross-sections contained elongated spermatids or sperm. Between days 360 and 420, tubule differentiation advanced further, until more than 45% of the tubule cross-sections contained elongated spermatids or sperm. Sperm were recovered for the first time from a single mouse in the 55-dpi group on day 180, although on days 360-420 sperm were recovered from most mice in all of the groups. Serum concentrations of inhibin and testosterone in host mice in all of the groups were higher than those in castrated mice that had received no testicular grafts. Single sperm collected from mice in each group on day 300 or later were injected into individual in vitro-matured oocytes, and these sperm-injected oocytes were transferred to the oviducts of 2 or 3 estrus-synchronized recipient gilts. None of the recipients in any of the groups produced piglets. The present results clearly indicate that porcine fetal testes during the gestational period acquire endocrine and exocrine functions after being cryopreserved and grafted into nude mice. However, the ability of xenogeneic sperm derived from fetal testis to generate piglets was not confirmed in the present study.

Propriedades tensiométricas do peritônio da paca (Cuniculus paca) a fresco e conservado em glicerina 98 por cento / Tensiometer peritoneum properties of the paca (Cuniculus paca) fresh and preserved in glycerin 98 por cento

In constant searching for alternative biological material to perform implants and new options of experimental animal models, the objective of this investigation was to describe the mechanical properties of the peritoneum paca (Cuniculus paca Linnaeus, 1766) fresh and preserved in 98% glycerin. Samples of fresh and preserved in glycerin for periods of 30, 60 and 90 days were subjected to mechanical tests. Four adult animals, male or female, with mean body weight of eight kilograms, were used for collecting samples of the peritoneum. All tissues preserved in glycerin 98% showed a decrease in stiffness and increase in ductility and toughness. Considering the maximum force applied to the peritoneum, significant increase was observed in values (p<0.01) of samples stored for 60 and 90 days when compared to fresh material. In relation to the stretch variable, an increase was observed in all storage time of glycerin samples, verifying significant difference (p<0,01) when compared with the fresh samples. The variable area also showed significance (p <0.01) between the values of the fresh samples (5.40 mm²) and preserved in the glycerin by periods of 30 days (4.50 mm²), 60 days (9.00 mm²) and 90 days (7.20 mm²), thus indicating that the area of this membrane increased by 0.033 mm² per day. Generally, it was concluded that the 98% glycerin is a substance effective for the preservation of the peritoneum of the agouti paca, therefore improves its mechanical properties allowing the support membranes greater deformation forces. Thus, the results obtained in mechanical tests of the peritoneum of paca suggest its use as an alternative biological material.

Na busca constante, tanto de material biológico alternativo para a realização de implantes, quanto de novas opções de modelos de experimentação animal, o objetivo desta investigação foi descrever o comportamento mecânico do peritônio da paca (Cuniculus paca Linnaeus, 1766) a fresco e conservado em glicerina a 98%. Amostras frescas e conservadas em glicerina por períodos de 30, 60 e 90 dias foram submetidas a testes mecânicos de tração. Quatro animais adultos, três machos e uma fêmeas, com peso corporal médio de oito quilogramas, foram utilizados para colheita das amostras de peritônio. Todos os tecidos conservados em glicerina a 98% apresentaram diminuição na rigidez e aumento na ductibilidade e tenacidade. Considerando-se a força máxima aplicada ao peritônio, evidenciou-se aumento significativo nos valores (p<0,01) das amostras conservadas por 60 e 90 dias, quando comparado ao material a fresco. Com relação a variável alongamento, notou-se aumento nos valores relativos aos materiais em glicerina em todos os tempos de conservação, verificando-se diferença significativa (p<0,01) entre os valores das amostras a fresco. A variável área também se apresentou significativa (p<0,01) entre os valores das amostras a fresco (5,40 mm²) e os preservados em glicerina pelos períodos de 30 dias (4,50 mm²), 60 dias (9,00 mm²) e 90 dias (7,20 mm²), indicando assim, que a área desta membrana aumentou em 0,033 mm² por dia. Mediante os resultados observados, concluiu-se que a glicerina 98% é uma substância eficiente para a conservação do peritônio da paca, pois melhorou suas propriedades mecânicas permitindo que as membranas suportem maiores forças de deformação. Assim, os resultados obtidos nos ensaios mecânicos do peritônio da paca sugerem sua utilização como mais uma opção de material biológico.

Preliminary results of the application of gonadal tissue transfer in various chicken breeds in the poultry gene conservation.

The aim of the study was to devise a technique to allow transfer of ovarian and testicular tissues obtained from one day old chicks to recipient animals. The following combinations of chicken breeds were used: Tetra SL/Tetra SL, Tetra SL/Harco, Tetra SL/Black Transylvanian Naked Neck, Godollo New Hampshire/Speckled Transylvanian Naked Neck (recipient/donor), respectively. Only animals less than 24h old from hatching were used as either recipient or donor. Eggs yielding recipients were treated with busulfan to hinder the development of the recipient's own gonads. Gonads were transferred surgically to the new host which was then immunosuppressed for two months. The animals were checked at 8 or 16 weeks for the existence of implanted gonads, and if found, the gonads were removed for histology examination. Tetra SL/Tetra SL pairing resulted in successfully adhered and functioning gonads in most cases. In other combinations, no gonads originating from the donors were found in the recipients. We conclude that not all breeds seem to be suitable recipients; some breeds or individuals may show incompatibility to each other and further examination is needed to find the cause of incompatibility and to establish a suitable breed combination, which can be used for gonad transfer.

Regeneración de las lesiones críticas del nervio periférico con factores de crecimiento. Estudio experimental / Regeneration of critical injuries of the peripheral nerve with growth factors

Introducción. El objetivo del proyecto es estudiar la regeneración de las lesiones no reparables del nervio periférico, mediante un injerto muscular enriquecido con factores de crecimiento. Material y método. La experimentación se desarrolla en 2 fases: primero, comparamos la sutura directa del defecto crítico en el nervio ciático de 10 ratas, con la interposición de un injerto de músculo autólogo desnaturalizado por calor en otras 10. En la segunda, se comparan 10 ratas con reparación mediante injerto muscular acelular, con la inyección de 2 cc de IGF-1 (10 mg/ml de mecasermina, en solución inyectable) dentro del injerto acelular de otras 10. Realizamos el seguimiento clínico y el control funcional de la marcha, medición de la huella plantar y «Grasping Test». Fueron sacrificadas a los 90-100 días, obteniendo muestras para macro y microscopía, con tinciones de azul de toluidina, hematoxilina-eosina y tricrómico de Masson. Resultados. La primera experimentación demostró el hallazgo de tejido de características nerviosas en las secciones del injerto muscular. La segunda supuso una potenciación de los resultados: mejoría clínica posquirúrgica, precoz deambulación, descenso en la tasa de úlceras por presión en partes acras, recuperación de la huella plantar, e incremento del porcentaje de terminaciones nerviosas en regeneración del cabo distal (47-62%). Conclusiones. Exponemos en este trabajo las posibilidades experimentales y clínicas de la reparación del defecto nervioso mediante músculo desnaturalizado, confirmando la adecuación de la técnica. Además, confirmamos nuestra hipótesis con clínica y determinaciones celulares enriquecidas por la adicción de factores de crecimiento que impulsan la regeneración nerviosa (AU)

Introduction. This project aims to study the regeneration of non-repairable lesions of peripheral nerve by muscle grafts enhanced with growth factors. Material and methods. The experiment was carried out in two phases. The first one compared direct suture of a critical defect in the sciatic nerve of ten rats, with the interposition of autologous muscle graft, denatured by heat, in another ten. The second phase compared ten rats with nerve repair using an acellular muscle graft, with injection of 2 cc of IGF-1 (10 mg/ml mecasermin, Injectable solution) into the acellular graft of another ten. A clinical and functional follow-up was carried out including, ambulation, footprint measurement, and «Grasping Test». The animals were sacrificed at 90-100 days, and samples obtained for macro- and microscopic studies with toluidine blue, haematoxylin-eosin and Masson's trichrome staining. Results. The first experiment showed the characteristic findings of nerve tissue in muscle graft level sections. The second was an enhancement of the results: post-surgical clinical improvement, early ambulation, decrease in the rate of pressure ulcers in toes, recovery of the footprint, and increasing the percentage of nerve endings in distal sciatic regeneration (47-62%). Conclusions. In this study the experimental and clinical possibilities of nerve defect repair by denatured muscle are demonstrated, confirming the suitability of the technique. Furthermore, it confirms our hypothesis with clinical and cellular determinations enriched by the addition of growth factors that promote nerve regeneration (AU)

Oronasal fistula repair using auricular cartilage.

Seven oronasal fistula lesions secondary to extraction of maxillary canine teeth were treated in 5 dogs using a cartilage graft harvested from the ipsilateral auricular pinna. All dogs had undergone previous, unsuccessful surgeries in attempt to repair the defects. The technique is described in a step-by-step fashion for easy reproduction. The authors found the technique to be straightforward, relatively quick, and successful in all 7 lesions.

Repair of a scleral defect with an autogenous fascia lata graft in a dog.

A case of a traumatic scleral rupture with uveal herniation in a dog was treated with an autogenous fascia lata graft. Placement of the graft resolved the uveal prolapse and resulted in return of strength and a more normal structure. Fascia lata appears to be an effective scaffolding graft for the repair of scleral defects. It is cheap, easily harvested and large grafts may be obtained. Healing was rapid and the end result was a cosmetic, comfortable, fully functional eye.

The regenerative medicine laboratory: facilitating stem cell therapy for equine disease.

This article focuses on the emerging field of equine regenerative medicine with an emphasis on the use of mesenchymal stem cells (MSCs) for orthopedic diseases. We detail laboratory procedures and protocols for tissue handling and MSC isolation, characterization, expansion, and cryopreservation from bone marrow, fat, and placental tissues. We provide an overview of current clinical uses for equine MSCs and how MSCs function to heal tissues. Current laboratory practices in equine regenerative medicine mirror those in the human field. However, the translational use of autologous and allogeneic MSCs for patient therapy far exceeds what is currently permitted in human medicine.

The use of porcine small-intestinal submucosa for abdominal wall reconstruction--a clinical case.

A seven-year-old miniature dachshund was presented with a large contaminated bite wound centred on the left costal arch. Survey radiographs revealed a pneumomediastinum, a mid-body fracture of the left 11th rib and luxation of the xiphisternum. The compromised skin, ribs, xiphisternum, diaphragm and abdominal wall were surgically debrided. This resulted in a large combined thoracic and abdominal wall defect. The thoracic cavity was closed by diaphragmatic advancement. The abdominal wall defect was partially closed by advancing local abdominal musculature. A cranial abdominal mid-line defect remained and was repaired using two sheets of lyophilised porcine small-intestinal submucosa. Dehiscence of the skin exposing the SIS graft was seen but the abdominal repair remained intact. Eighteen months after the initial injury, the dog remained clinically well and no associated complications were reported.

Reconstruction of a large diaphragmatic defect in a kitten using small intestinal submucosa (SIS).

A double-layer sheet of small intestinal submucosa (SIS) was used to reconstruct a large chronic diaphragmatic defect in a 4-month-old kitten. The SIS graft was easy to use, postoperative recovery was uneventful, no side effects of the SIS implant were observed, and the SIS graft resulted in restoration of normal clinical function while allowing growth of the kitten without restriction of chest wall development. Herniation of fat through the caval hiatus was diagnosed 29 months postoperatively on a CT scan. The cat was free of clinical signs.

Effect of bovine freeze-dried amniotic membrane (Amnisite-BA) on uncomplicated canine corneal erosion.

OBJECTIVE: To evaluate the effectiveness of bovine freeze-dried amniotic membrane (FD-AM) (Amnisite-BA) in the surgical treatment of corneal ulceration in dogs. ANIMALS STUDIED: Eight normal Shih-tzu dogs. PROCEDURES: The corneas of 16 eyes were scored with an 8.0-mm trephine under general anesthetic and 100% ethanol was applied to remove a standardized button of corneal epithelium. The eyes were treated as described below and the corneas were evaluated 48 h later. The dogs were divided into four treatment groups: (i) control, (ii) amniotic membrane transplantation (AMT), (iii) nictitating membrane flap and (iv) contact lens. The proportion of the corneal wound that healed was calculated and all eyes were enucleated. Histological sections of cornea were assessed with the proliferating cell nuclear antigen (PCNA) assay. RESULTS: The proportion of corneas healed in the different treatment groups was (i) 38.02%, (ii) 89.15%, (iii) 52.31%, and (iv) 60.56%. Epithelial healing was significantly increased in the AMT group (ii) (P = 0.001) while groups (iii) and (iv) were not significantly different from the control group (P = 0.537 and P = 0.198, respectively). The number of PCNA positive cells was (i) 275.00, (ii) 740.50, (iii) 285.75 and (iv) 420.59, these varying compared with the control group with statistical significance of (ii) P = 0.002, (iii) P = 0.999, and (iv) P = 0.467. The greatest healing rate and epithelial cell proliferation was achieved with AMT compared to the other treatment regimes. CONCLUSIONS: The results of this study show that FD-AM transplantation is an effective treatment for enhancing canine corneal wound healing and suggest that the approach will provide superior results compared to conventional treatments for the condition.

Pearl formation: persistence of the graft during the entire process of biomineralization.

Most bivalves species of the genus Pinctada are well known throughout the world for production of white or black pearls of high commercial value. For cultured pearl production, a mantle allograft from a donor is implanted into the gonad of a recipient oyster, together with a small inorganic bead. Because of the dedifferentiation of cells during the first steps of the host oyster's immunological reaction, so far the fate of the graft and its exact role in the process of pearl formation could not be determined via classical histological methods. Here we report the first molecular evidence of the resilience of the graft in the recipient organism by showing that cells containing genome from the donor are still present at the end of pearl formation. These results suggest the existence of a unique biological cooperation leading to the successful biomineralization process of nacreous secretion in pearl formation.

Buccal mucosal graft urethroplasty for reversal of a perineal urethrostomy in a goat wether.

OBJECTIVE: To describe the use of buccal mucosa as a urethral graft for reversal of perineal urethrostomy (PU) in a castrated male goat. STUDY DESIGN: Clinical case report. SAMPLE POPULATION: One client-owned castrated male goat. RESULTS: An 8-month-old Pygmy cross wether was admitted for urolithiasis and PU stricture. After repeated unsuccessful attempts at urethrostomy reversal and urethral reconstruction, a buccal mucosal graft was used for urethroplasty. Buccal mucosa proved to be an excellent graft for urethral repair. Normal urination has occurred through the reconstructed region for at least 24 months. CONCLUSIONS: Buccal mucosa worked well as a graft for urethroplasty and PU reversal. CLINICAL RELEVANCE: Grafting with buccal mucosa may also prove useful in other urethral repair techniques in small ruminants.

Differentiation and developmental potential of rat post-implantation embryo without extra-embryonic membranes cultured in vitro or grafted in vivo.

Different experimental systems are used to study developmental processes in mammals. In this study, three experimental models were analysed and correlated: (1) cultivation of rat embryos in vitro; (2) cultivation in vitro and then transplantation in vivo; (3) direct transplantation in vivo. When embryos were cultivated in vitro and then transplanted in vivo, after the initial in vitro restriction, developmental potential was recovered. The in vitro restriction depended on medium used and duration of culture. Pre-cultivation in serum-free medium for 7 days restricted developmental potential for nervous tissue, and for 14 days restricted developmental potential for skeletal muscles, adipose tissue and glandular epithelia. Transferrin addition improved in vitro differentiation of neuroblasts, cartilage and columnar epithelium. In the combined in vitro and in vivo method, transferrin preserved developmental potential in comparable extent to the addition of the serum. Even in serum-free conditions in vitro, the subsequent in vivo wide expression of developmental potential was possible. Therefore, the combination of in vitro and in vivo methods turned to be advantageous than the isolated approaches (in vitro or in vivo only), and enabled testing in more detail the influence of a single substance on developmental course and potential.

Development of a free latissimus dorsi muscle flap in cats.

Anatomic and experimental evaluation of the feline latissimus dorsi muscle was performed to assess its potential use as a free muscle flap. In the anatomic study, nonselective angiography of the subscapular artery was performed in nine heparinized feline cadavers. The muscle dimensions and vascular anatomy of the dissected latissimus dorsi muscle were recorded. In the experimental study four cats underwent heterotopic transplantation of a partial latissimus dorsi flap, and three cats underwent orthotopic transplantation of a complete latissimus dorsi flap. The mean length and width of the latissimus dorsi muscle was 19.0 and 5.4 cm, respectively. The dominant vascular pedicle was the thoracodorsal artery and vein. The average length and diameter of the thoracodorsal artery was 2.7 cm and 0.6 mm, respectively. Minor vascular pedicles were provided by branches of the intercostal arteries. Numerous choke anastomoses existed between the two pedicle systems. Viability of muscle flaps based on subjective evaluation, angiography, and histopathology, was 66% and 100% in the heterotopic and orthotopic studies, respectively. Flap failure seemed to be caused by both arterial and venous thrombosis. The latissimus dorsi muscle flap met criteria required for application in microvascular reconstruction. The vascular pattern was appropriate and consistent. Donor site morbidity was low, whereas surgical accessibility was high. The muscle satisfied the physical criteria of a free flap. Long-term anastomotic patency and flap viability was shown.