Effects of canine adipose-derived mesenchymal stem cells on the epithelialization of rabbits' skin autograft (Oryctolagus cuniculus) / Efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães na epitelização de autoenxertos de pele em coelhos (Oryctolagus cuniculus)

The present study aimed to evaluate the effects of mesenchymal stem cells derived from canine adipose tissue in the healing process of full-thickness mesh skin grafts in rabbits. The stem cells were collected from young dogs; and, after characterization, remained in cryopreservation, in independent doses containing 2 x 106 cells. The mesh distal limb graft technique was performed in 60 rabbits, divided into three groups, CG (Control Group), GT1 (Intralesional Stem Cell Treated Group), and GT2 (Intravenous Stem Cell Treated Group), containing 20 animals each. After grafting, each group was randomly divided into four subgroups according to euthanasia time 3, 7, 14, and 30 days, containing five animals in each group. Animals of GT1_14, GT1_30, and GT2_14, GT2_30 subgroups received a second dose of xenogeneic cells on the seventh day. Meanwhile, animals from GT1_30 and GT2_30 received the third dose of xenogeneic cells on day 14. The groups treated with xenogeneic stem cells positively affected type III collagen re-epithelialization and deposition, and possibly GT1 had a controlled inflammatory response. However, no effect on angiogenesis. Thus, it was possible to demonstrate tolerance and therapeutic action of mesenchymal stem cells from canine adipose tissue in skin grafts in rabbits.(AU)

O presente estudo teve como principal objetivo avaliar os efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães no processo de cicatrização de autoenxertos de pele de espessura total em malha em coelhos. As células-tronco foram coletadas de cães jovens, após a caracterização estas permaneceram em criopreservação, em doses individuais contendo 2 x 106 células. A técnica de enxerto em malha na região distal do membro foi realizada em 60 coelhos, divididos em três grupos, GC (Grupo Controle), GT1 (Grupo tratado com células-tronco intralesional) e GT2 (Grupo tratado com células-tronco via endovenosa), contendo 20 animais cada. Imediatamente após a enxertia, cada grupo foi dividido aleatoriamente em quatro subgrupos, de acordo com o tempo de eutanásia 3, 7, 14 e 30 dias contendo cinco animais cada. Animais dos subgrupos GT1_14, GT1_30 e GT2_14, GT2_30 receberam uma segunda dose de células xenógenas no sétimo dia. Ademais, animais do GT1_30 e do GT2_30 receberam a terceira dose de células xenógenas no dia 14. Os grupos tratados com células-tronco xenógenas tiveram um efeito positivo na reepitelização e deposição de colágeno tipo III, e possivelmente, o GT1 teve uma resposta inflamatória controlada, entretanto o efeito na angiogênese não foi observado. Dessa forma, foi possível demonstrar que houve tolerância e ação terapêutica das células-tronco mesenquimais derivadas do tecido adiposo de cães em enxertos de pele em coelhos.(AU)

Topical application of lidocaine or bupivacaine in the healing of surgical wounds in dogs.

PURPOSE: To analyze the anesthetic drugs interference with wound healing when used in the surgical bed. METHODS: Macro and microscopic aspects of healing of surgical wounds were evaluated after instillation of topical anesthetics without vasoconstrictor or saline solution 0.9% as control in the transsurgical period. Thirty dogs, males and females were divided into two experimental groups. In both groups, two circular punch lesions of 6 mm diameter were performed in the abdomen. In group 1, lidocaine was instilled in one of the lesions and saline solution in the contralateral lesion. In group 2 the procedure was repeated with the use of bupivacaine. The macroscopic assessment of the lesions was performed on the first, third and tenth postoperative day. The excisional biopsy was performed on the tenth day and the samples were submitted for histopathological examination. RESULTS: The macroscopic analysis had a significant difference between groups. Microscopic analysis was not significant between groups. CONCLUSIONS: The topical application of lidocaine and bupivacaine in the surgical wound is feasible and it does not influence skin healing. The benefit of such a practice, which has been the subject of other studies, seems to outweigh the risks.

The feasibility and effectiveness of thoracoscopic transdiaphragmatic approach for lung biopsy in rabbits. A randomized study.

PURPOSE: To assess the feasibility of thoracoscopic transdiaphragmatic approach for biopsy of all lung lobes and to determine the optimal intercostal space (ICS) for biopsy of each lung lobe. METHODS: Ten rabbits were positioned in dorsal recumbency. Total thoracoscopy lung biopsy was made combined transdiaphragmatic approach and right ICS approaches. A camera port was made in the transdiaphragmatic approach and the instrument port was made of ICS 7 and ICS 9. A pre tied loop ligature was placed to performed a caudal lung lobe biopsy and to simulate biopsies of the others lung lobes. RESULTS: Biopsy of the cranial aspect of the right caudal lung lobe was performed at ICS 9. Simulated biopsy of the accessory lung lobe was performed at ICS 9. Simulated lung biopsy of the right cranial and middle lung lobes was performed at ICS 7. The caudal and dorsal aspect of the right caudal lung lobe was not visualized by telescope at transdiaphragmatic approach, and biopsy was not performed. CONCLUSIONS: Thoracoscopic transdiaphragmatic approach for lung lobes biopsies was a feasible technique, except for the caudal aspect of the right caudal lung lobe. An ideal intercostal port for biopsy of each right lung lobe was determined.

Topical application of lidocaine or bupivacaine in the healing of surgical wounds in dogs

Abstract Purpose: To analyze the anesthetic drugs interference with wound healing when used in the surgical bed. Methods: Macro and microscopic aspects of healing of surgical wounds were evaluated after instillation of topical anesthetics without vasoconstrictor or saline solution 0.9% as control in the transsurgical period. Thirty dogs, males and females were divided into two experimental groups. In both groups, two circular punch lesions of 6 mm diameter were performed in the abdomen. In group 1, lidocaine was instilled in one of the lesions and saline solution in the contralateral lesion. In group 2 the procedure was repeated with the use of bupivacaine. The macroscopic assessment of the lesions was performed on the first, third and tenth postoperative day. The excisional biopsy was performed on the tenth day and the samples were submitted for histopathological examination. Results: The macroscopic analysis had a significant difference between groups. Microscopic analysis was not significant between groups. Conclusions: The topical application of lidocaine and bupivacaine in the surgical wound is feasible and it does not influence skin healing. The benefit of such a practice, which has been the subject of other studies, seems to outweigh the risks.

Squamous cell carcinoma of unknown primary origin in a dog presenting with bone metastasis.

A 10-year-old female American Pit Bull dog was diagnosed with metastatic undifferentiated carcinoma of the scapula. Immunohistochemistry showed positive immunoexpression for cytokeratins (AE1/AE3, 34BE12, CK7) and vimentin, confirming squamous cell carcinoma. No evidence of nodules was found in the complete physical examination and imaging procedures conducted. The patient was diagnosed with carcinoma of unknown primary origin. Amputation and adjuvant chemotherapy with doxorubicin and piroxicam were performed, but the patient died of respiratory failure after 737 days of diagnosis. Necropsy confirmed undifferentiated carcinoma infiltrating the lungs and kidneys, and showing the same immunoexpression as the tumor in the scapula. Amputation associated with chemotherapy extended the overall survival time of this patient.