Fernanda Silveira Nóbrega

Modelo experimental de aneurisma sacular de artéria ilíaca comum com pericárdio bovino em suínos

Objective: To develop an experimental model of saccular pseudoaneurysm of the common iliac artery with bovine pericardium in pigs. Method: The animals used were two 30-kg female pigs from the Landrace specimen. The animals were submitted to general anesthesia and laparotomy with extraperitoneal access to infrarenal aorta and the iliac arteries. After systemic heparin and clamping, the iliac artery was opened and the pericardium sutured to the vessel wall. All animals were confined for 3 weeks and were sacrificed after performing an arteriography to verify the patency of the aneurysm. Result: All animals survived the procedure and the aneurysms were patent. No rupture was detected. Conclusion: This is a feasible pig model of iliac artery aneurysm with potential for further studies to develop new endovascular prostheses.

Aterogênese em artéria ilíaca comum de suínos submetidos à homocisteinemia induzida pela ingestão de metionina

Objective: To assess the effects of induced homocystinemia in the swine iliac artery. Material and method: A comparative experimental study with two homogeneous groups of seven pigs from the Macao specimen, weighed between 20 and 30 kg, which were assessed during 30 days. The pigs were divided into two groups. One of them was fed with a methionine-rich diet for a 4-week period. Blood samples were collected for analyses of total cholesterol, triglycerides, HDL and homocysteine concentrations. The animals were submitted to arteriography to evaluate the patency of iliac arteries and then sacrificed. The iliac artery segment was removed for histological analysis. Results: All animals survived the procedure, and there were no significant changes in total cholesterol, triglycerides and HDL concentrations in both groups. Microscopic examinations of the control group did not show pathological changes and was similar in all analyses. In the group receiving the methionine diet, the plaques were formed by foamy macrophages, but smooth muscle cells, cholesterol crystals or inflammatory cells were not seen. The tunica media had the internal elastic lamina intact. In the control group, there was no change in homocysteine levels during the experiment. In the methionine group, there was an increase in plasma homocysteine levels, with an average value of 59.80 µmol/l after 30 days with a methionine-rich diet. Conclusion: Homocystinemia induced by methionine causes atherogenesis in the swine iliac artery.

Videolaparoscopia topográfica de equinos em estação com três diferentes massas corpóreas

The present study aimed to perform an anatomic description of the abdominal cavity of equines in standing position. Twenty-one healthy equines were allotted into three groups according to their corporal mass. Animals weighing up to 250kg were included in group A, 251 to 350kg in group B and over than 351kg in group C. Laparoscopy was the surgical technique performed, with access through the left and right paralumbar fossas using a video-assisted introduction of cannula, starting from the left flank. This first access allowed the observation of the diaphragm, stomach, left hepatic lobe, spleen, renal area, small intestine, descending colon, bladder, rectum and internal reproductive organs of the male and female. During the right access were observed: diaphragm, right hepatic lobe, renal area, dorsal colon, duodenum, cecum, small intestine, descending colon, bladder, rectum and internal reproductive organs of the male and female. The video-laparoscopic for the study of the abdominal anatomy of equines is feasible, and no limitations due to animal size have been observed.

Osteossíntese de tíbia com fixador esquelético externo em um cordeiro

Entre os avancos que a clinica e cirurgia veterinaria apresentaram nos ultimos anos, o tratamento de fraturas em grandes animais pode ser citado como um exemplo. A experiencia, consolidada em outras especies de menor porte, permite a tentativa de extrapolar a mesma para as especies de maior porte, adequando-se sempre as caracteristicas e particularidades de cada especie. Atualmente, devemos considerar o tratamento de fraturas de animais de producao como uma forma de evitar o seu descarte, uma vez que, quando se trata de um animal reprodutor, devemos ter a opcao de trata-lo ao inves de decidir pela eutanasia. O presente estudo relata um caso de fratura transversa de diafise de tibia de membro posterior esquerdo em um cordeiro sem raca definida, com duas semanas de idade, com historico de pisoteamento por um bovino. Foi utilizada fixacao esqueletica externa tipo II para a osteossintese, obtendo-se eficiente estabilizacao da fratura. O animal ficou hospitalizado durante todo o periodo de pos-operatorio e a consolidacao ossea foi obtida em 30 dias.

Histologic and immunohistochemical evaluation of biocompatibility of castor oil polyurethane polymer with calcium carbonate in equine bone tissue

OBJECTIVE To evaluate the efficacy of castor oil polyurethane polymer with calcium carbonate for use in a unicortical ostectomy on the dorsal surface of the third metacarpal bone of horses. ANIMALS 6 adult horses. PROCEDURES A unicortical ostectomy was created on the dorsal surface of both third metacarpal bones of each horse. Castor bean (Ricinus communis) oil polyurethane polymer with calcium carbonate was implanted into the ostectomy on 1 limb, and the ostectomy of the contralateral limb was left unfilled and served as a control sample. Ostectomy sites were evaluated histologically 120 days later. Biopsy specimens were obtained from the interface of bone and polymer or the interface of bone and newly formed tissue; specimens were processed for histomorphometric evaluation by use of light microscopy, immunohistochemical analysis, histochemical analysis, and transmission electron microscopy. RESULTS Osteoconductive activity of the biomaterial was confirmed by the presence of osteoblasts in the biopsy specimens. Absence of a chronic inflammatory response or foreign body reaction indicated biocompatibility. Expression of osteoblast markers was detected in the newly formed tissue. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that castor oil polyurethane polymer with calcium carbonate could be an acceptable compound for use as a bone substitute in horses with fractures in which bone filling is necessary.

Comparison of lyophilization, and freezing in honey as techniques to preserve cortical bone allografts used to repair experimental femoral defects in domestic adult cats

Cats with orthopedic conditions are a prominent part of the clinical work of veterinary. Conditions such as comminuted fractures, bone tumors and non-unions are often difficult to repair and may require the use of bone grafts for treatment. This study evaluated cortical bone allografts preserved in honey, frozen or lyophilized for correcting long bone defects created in the diaphysis of the right femur of domestic cats (n=24). In the control group (n=6), the defect was repaired using autogenous cortical bone graft. In the remaining animals (n=6/group), the defect was repaired with cortical bone allografts preserved in honey, frozen or lyophilized. Success of graft incorporation and length of time for consolidation were assessed through clinical, radiographic and histological evaluations performed up to 180 days. In the control, frozen, honey and lyophylized groups, respectively, success of graft incorporation was 91.6%, 83.3%, 75%, and 25%, with corresponding mean length of time for consolidation of 83.1, 78, 105 and 120 days. Incorporation percentage in the lyophilized group was significantly lower than in the frozen and control groups. In conclusion, bone grafts preserved in honey or frozen were effective for repairing cortical defects in the femurs of cats as compared to autogenous cortical bone grafts.

Mielomalácia hemorrágica progressiva em cão

Mielomalacia e a necrose isquemica ou hemorragica da medula espinhal, que pode ocorrer como sequela de uma lesao ocasionada por um trauma espinhal agudo. A mielomalacia pode ser focal ou difusa, sendo a lesao caracterizada por uma combinacao de infarto isquemico e hemorragico do parenquima do cordao espinhal, que migra tanto de forma ascendente como descendente, causando lesoes neurologicas irreversiveis e compativeis com a regiao afetada. Um canino da raca dachshund, cinco anos e 6,7kg foi atendido no Hospital de Clinicas Veterinarias (HCV) da Universidade Federal do Rio Grande do Sul (UFRGS). No exame neurologico apresentou paralisia de membros posteriores, com ausencia de dor profunda e reflexo patelar aumentado. Foi in iciada terapeutica com prednisolona e repouso absoluto, sendo recomendada a reavaliacao em dois dias. No retorno, o canino apresentou tetraparalisia, ausencia de dor profunda nos membros anteriores e posteriores, dispneia e hipotermia. Apos exame radiografico e com base nos sinais clinicos do animal, suspeitou-se de mielomalacia hemorragica progressiva, que foi confirmado no exame de necropsia.