Márcio Botelho de Castro

Clinical, parasitological and immunological aspects of experimental infection with Trypanosoma evansi in dogs.

This research investigated the pattern of antibody response by means of enzyme linked immunosorbent assay (Elisa) and indirect fluorescent antibody test (IFAT) through the course of experimental Trypanosoma evansi infection in dogs. Clinical and parasitological features were also studied. The average prepatent period was 11.2 days and parasitaemia showed an undulating course. Biometrical study of parasites revealed a mean total length of 21.68mm. The disease was characterized by intermittent fever closely related to the degree of parasitaemia and main clinical signs consisted of pallor of mucous membrane, edema, progressive emaciation and enlargement of palpable lymph nodes. Diagnostic antibody was detected within 12 to 15 days and 15 to 19 days of infection by IFAT and Elisa, respectively. High and persistent antibody levels were detected by both tests and appeared not to correlate with control of parasitaemia

Hematological, biochemical and anatomopathological aspects of the experimental infection with Trypanosoma evansi in dogs

O presente estudo acompanhou durante 82 dias o curso da infeccao experimental com T. evansi em quatro caes, realizando a avaliacao dos achados hematologicos, bioquimicos e anatomopatologicos. Os animais infectados mostraram declinio acentuado na contagem de hemacias, hematocrito e teor de hemoglobina, permanecendo anemicos a partir da terceira semana de infeccao ate o final do periodo experimental. Leucopenia com neutropenia foram observadas entre a segunda e a quinta semanas apos a infeccao. Os caes inoculados desenvolveram hiperproteinemia, sendo constatada diminuicao na relacao albumina:globulina. As atividades sericas de alamina aminotransferase e aspartato aminotransferase aumentaram significativamente nos caes infectados em relacao aos animais controle. O exame histopatologico revelou hiperplasia linfoide no baco e linfonodos e infiltrado mononuclear periportal e esteatose de padrao centrolobular no figado de todos os caes infectados. Intenso infiltrado mononuclear foi observado no miocardio de tres caes e acumulos de celulas mononucleares junto as meninges foram evidenciados em dois animais infectados.

Biocompatibilidade do cimento de fosfato de cálcio implantado no rádio de coelhos

PURPOSE: The objective of this paper was to evaluate the biocompatibility of calcium phosphate cement in radius of rabbits. METHODS: For this experiment, calcium phosphate were implanted in the radius of 16 rabbits, divided in two groups (GI and GII), according to postoperative follow-up of 12 and 26 weeks, respectively. Reactions of these biomaterials on animal bone tissue were observed. X-ray, optical densitometry, optical microscopy and scanning electron microscopy analyses were performed. RESULTS: It was observed that calcium phosphate cement were partially resorbed during the 26-week follow-up, showing biocompatibility, with absence of inflammatory or other undesirable reactions due to the implants. CONCLUSIONS: Calcium phosphate-based cements did not cause inflammatory reactions when in contact with the osseous tissue, and were therefore biocompatible. Follow-up periods longer than 26 weeks are necessary to better evaluate the behavior of calcium phosphate-based cement.

Análise macroscópica e histológica do emprego da poliuretana derivada do óleo de mamona (Ricinus communis) aplicada na tíbia de cães em fase de crescimento

PURPOSE: To analyze the effects of castor oil derived poliurethane, when applied to bones of puppies. METHODS: Twelve dogs, randomly divided in 3 groups, received a castor oil derived poliurethane at the medial side of the proximal tibia. Gross and histopathologic evaluations were performed at 30 (GIII), 60 (GII) and 90 (GI) days. RESULTS: The poliurethane was enclosed in a connective fibrous tissue capsule and there was no new bone formation around it. CONCLUSION: The castor oil derived poliurethane is biocompatible and behaves as a biological stand off in dogs. Osteointegration does not occur in this species.

VISCERAL MAST CELL TUMOR IN A CAPTIVE BLACK JAGUAR (PANTHERA ONCA)

Abstract Little is known about neoplasia in the jaguar (Panthera onca), the largest American feline. A captive black jaguar was diagnosed at necropsy with a mastocytic form of visceral mast cell tumor similar to that which occurs in domestic cats. This animal had no previous clinical disease and died during anesthesia for a routine dental treatment.

Estudo comparativo da cicatrização de enterorrafias em planos aposicional e invaginante no cólon descendente de eqüinos

This trial was carried out in order to compare the healing process of the descending colon in horses, submitted to two distinctive suture techniques - appositional pattern and inverting pattern. Fifteen healthy horses were used and the surgical intervention was accomplished with the animals in right lateral recumbency, under inhalatory anesthesia. The abdominal cavity approach was done by the left flank, and after exteriorization of the descending colon, two enterotomies, 5cm long, and 20cm apart one from each other were done. The horses were randomly distributed into five groups of three animals each. After a humane method of euthanasia, necropsies were performed with complete inspection and documentation of the sutured areas of the descending colon on postoperative days 3, 7, 14, 21, and 35, one group at each time. At necropsy, no alterations were noticed in abdominal cavity and organs although some adhesions were observed. In nine horses adhesions at the appositional pattern suture (60.0% ± 12.6) were found. Four horses presented adhesions at the inverting suture (26.6% ± 11.4). No signs of intestinal flow impairment were found. Regarding the histopathological findings, the majority of the wounds were almost completely healed on day seven after surgery. The suture thread poliglactin 910, used in both suture types, worked well during and after surgery, but it is believed that it was the cause of the observed granulomatous inflammatory reaction.

Placas de aço inoxidável 316L aplicadas no reparo de fratura experimental diafisária do rádio e ulna de cães

A long-term study was carried out for evaluating 316L stainless steel plates with different types of finish used in the repair of experimetnal radial and ulnar dyaphisial fractures in dogs and the possible interference of this reaction in bone consolidation. Semi-finished, polished, blasted with glass microbeads and passivated plates were applied to the distal epiphysis of the radius of anesthetized dogs. Twelve animals were divided into two groups, GI (six dogs) and GII (six dogs), which underwent osteosynthesis (OS) in both bones, after bilateral radial and ulnar osteotomy, totaling 24 procedures. The clinical and radiographic evolution of the regions that received the implant was studied at 30, 60, 90, 180, 240 and 360 days after OS. The animals from GI were killed at 180 days and those from GII at 360 days for histopathological analysis of the bones at the implant region (optical and electronic-scanning microscopy) and to study corrosion on the metallic implants, through chemical and metallographic analysis (optical and eletronic-scanning microscopy and scattered-energy spectroscopy). Limb function was recovered 24h after surgery. Upon X-ray examination, bone consolidation was observed in all animals. Both in macroscopic and microscopically, no signs of metallic corrosion were observed, except for one passivated plate implanted in one animal of GII, in which the phenomenon was observed through optical and electronic-scanning microscopy. This study allows to conclude that 316L stainless steel plates, regardless of the surface treatment, did not undergo corrosion or adverse reactions and were effective in the treatment of experimental radial and ulnar fractures in dogs.