Genilson Fernandes de Queiroz

Vascular Endothelial Growth Factor Expression and Microvascular Density in Soft Tissue Sarcomas in Dogs

The aim of the current study was to evaluate the expression of vascular endothelial growth factor (VEGF) and the microvascular density in canine soft-tissue sarcomas. Immunohistochemistry for VEGF expression was performed on 20 canine neoplasms by the streptavidin–biotin–peroxidase method using an anti-VEGF mouse monoclonal antibody (ab-119). The volume fraction of microvessels in the sarcomas was quantified in hematoxylin and eosin–stained tissue sections. At least 10 fields of view (40x magnification) per neoplasm were analyzed by positioning a grid with 100 points and counting the microvessels that fell into the intersection points. This percentage was considered the volume fraction of these microvessels in the tumor section. VEGF expression was detected in 65% of the neoplasms. In 92.3% of the neoplasms, the expression occurred in the peritumor region; in 46.15%, in the intratumor region; and in 38.46%, the expression was present in both regions. The cells responsible for VEGF expression were fibroblasts and macrophages in the peritumor region or in the pseudocapsule and neoplastic cells in the intratumor region. Greater intratumoral VEGF was expressed in hemangiopericytomas (P = 0.04). No difference was present in the volume fraction of tumor microvessels between VEGF-positive and VEGF-negative neoplasms (P = 0.3416) or for the different types of neoplasms (P = 0.5). The results of this study suggest that VEGF participates in the angiogenesis of soft-tissue sarcoma in dogs. Additional research will be necessary to elucidate the contribution of VEGF to the progression of malignancy.

Clinical Study of Cryosurgery Efficacy in the Treatment of Skin and Subcutaneous Tumors in Dogs and Cats

OBJECTIVE To evaluate the efficacy of cryosurgery for treatment of skin and subcutaneous tumors in dogs and cats. STUDY DESIGN Prospective study. ANIMALS Dogs (n=20), cats (10). METHODS Cutaneous or subcutaneous tumors were treated by liquid nitrogen cryosurgical spray (1 cm from target tissue at 90 degrees until a 5-mm halo of frozen tissue was achieved) for 15-60 seconds. Malignant lesions had 3 freeze-thaw cycles benign tumors, 2 cycles. The second or third freeze cycle was performed after complete thaw of the preceding freeze. Wounds healed by second intention. Follow-up was weekly for 1 month and then twice monthly until wounds healed, and final outcome was determined by telephone interview of owners. RESULTS Tumor size ranged from 0.3 to 11 cm diameter with 28 (60%) being 0.3-1 cm; 8 (17%) 1.1-3 cm, and 11 (23%) >3.4 cm. Complications included edema, erythema and for extremity lesions, pain and lameness. Treated lesions (n=47) had an overall remission of 98% (mean follow-up, 345+/-172.02 days [range, 150-750 days]). One malignant peripheral nerve sheath tumor recurred 7 months after cryosurgical treatment. CONCLUSION Cryosurgery is an efficient method for treatment of skin and subcutaneous tumors in dogs and cats. CLINICAL RELEVANCE Cryosurgical ablation is an effective means of treating small cutaneous or subcutaneous tumors in dogs and cats, especially in older animals where wound closure or cosmetic outcome might limit surgical excision alone.

Predictive values of aspartate aminotransferase and gamma-glutamyl transferase for the hepatic accumulation of copper in cattle and buffalo.

Ten cattle and 10 buffalo were divided into 2 groups (control [n = 8] and experimental [n = 12]) that received daily administration of copper. Three hepatic biopsies and blood samples were performed on days 0, 45, and 105. The concentration of hepatic copper was determined by spectrophotometric atomic absorption, and the activities of aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) were analyzed. Regression analyses were done to verify the possible existing relationship between enzymatic activity and concentration of hepatic copper. Sensitivity, specificity, accuracy, and positive and negative predictive values were determined. The serum activities of AST and GGT had coefficients of determination that were excellent predictive indicators of hepatic copper accumulation in cattle, while only GGT serum activity was predictive of hepatic copper accumulation in buffalo. Elevated serum GGT activity may be indicative of increased concentrations of hepatic copper even in cattle and buffalo that appear to be clinically healthy. Thus, prophylactic measures can be implemented to prevent the onset of a hemolytic crisis that is characteristic of copper intoxication.

Biópsia hepática por laparotomia paracostal em bovinos e búfalos

Liver biopsy in ruminants is an important technique for clinical diagnosis of toxic and metabolic diseases, especially mineral disorders. The most frequent procedures used so far results in an small amount of liver and not enough for multiple tests. The present study aims to evaluate the efficacy of paracostal laparotomy liver biopsy technique in cattle and buffalo and to follow possible changes on biochemical and hematological profiles caused by the surgery. Ten cattle and ten buffalo were used in this study. The animals were kept on their normal position and sedated with xilazin and locally infiltrated with lidocain and epinefrin. The access to abdominal cavity was carried through a right paracoastal laparotomy, ventrally to the transverse process of 2nd or 3rd lombar vertebra. A small portion of the hepatic caudal lobe (2 to 4g) was clinched by a Doyen clamp and removed. The abdominal cavity was closed as normally routine. Blood samples were taken to biochemical tests and hemogram before the procedure, and 24h, 48h, 5 and 10 days later. The technique was practical and easy to be performed (took approximately 25 minutes). The technique described here was efficient and offers low risk to animal health and provided enough amount of liver tissue for multiple tests.

Uso do propofol na indução anestésica de cutias (Dasyprocta sp.)

The endovenous use of propofol as inductor agent of anesthesia in agouti (Dasyprocta sp.) was evaluated using ten adut females, weighing 1.5 to 2.0kg, kept in captivity. Heart and respiratory rates, rectal temperature, and systolic arterial blood pressure were measured before and after anesthesia. Time of anesthesia and time of recovering of the anesthesia were also measured. The averages of the heart and respiratory rates, rectal temperature and the systolic blood pressure were 220bpm, 92mpm, 38.95oC, and 110Hgmm, respectively. After the induction, the averages obtained for those variables were of 214bpm, 84mpm, 39.05oC, and 80mmHg, respectively. The averages of the time of anesthesia and time of its recovery were 10min 45sec and 15min 40sec, respectively. Propofol when used in only one dose, was considered safe, since it did not disturbe the physiological parameters. Thus, propofol can be considered an alternative drug for anesthesia induction in agouti.