Objective—To determine the effect of a commercial
bioflavonoid antioxidant on acetaminophen-induced
oxidative injury to feline erythrocytes.
Design—Randomized controlled study.
Animals—45 healthy age-matched cats.
Procedure—Cats were assigned to 3 experimental
groups. Groups 1 and 3 received a bioflavonoid antioxidant
(10 mg/d) orally for 2 weeks. Groups 2 and 3
received an oxidative challenge with acetaminophen
(90 mg/kg [41 mg/lb] of body weight, PO) on day 7.
Packed cell volume, percentage of erythrocytes with
Heinz bodies, blood methemoglobin concentration,
and blood reduced and oxidized glutathione concentrations
were determined at various times during the
2-week study period.
Results—Adverse effects were not associated with
bioflavonoid antioxidant administration alone.
Acetaminophen administration resulted in a significant
increase in methemoglobin concentration in groups 2
and 3; differences were not detected between these
groups. Heinz body concentrations in groups 2 and 3
increased after acetaminophen administration; however,
the increase in cats that received the antioxidant
was significantly less than in group-2 cats. Total blood
glutathione concentrations did not change significantly
in groups 2 and 3 after acetaminophen administration;
however, ratio of reduced to oxidized glutathione
concentration increased significantly after administration
in group-2 cats, compared with group-3 cats.
Conclusions and Clinical Relevance—Oral administration
of bioflavonoid antioxidants to cats at risk for
oxidative stress may have a beneficial effect on their
ability to resist oxidative injury to erythrocytes. (J Am
Vet Med Assoc 2000;217:1157–1161)
Objective—To determine whether antemortem core needle biopsy and fine-needle aspiration of enlarged peripheral lymph nodes could be used to distinguish between inflammation and lymphosarcoma in cattle.
Animals—25 cattle with enlarged peripheral lymph nodes.
Procedures—Antemortem biopsies of the selected lymph nodes were performed with an 18-gauge, 12-cm core needle biopsy instrument. Fine-needle aspirates were performed with a 20-gauge, 4-cm needle. Specimens were analyzed by pathologists who were unaware of clinical findings and final necropsy findings, and specimens were categorized as reactive, neoplastic, or nondiagnostic for comparison with necropsy results.
Results—Sensitivity and specificity of core needle biopsy ranged from 38% to 67% and from 80% to 25%, respectively. Sensitivity of fine-needle aspiration ranged from 41% to 53%, and specificity was 100%. Predictive values for positive test results ranged from 77% to 89% for core needle biopsy and were 100% for fine-needle aspiration. Predictive values for negative test results were low for both core needle biopsy and fine-needle aspiration.
Conclusions and Clinical Relevance—Results indicated that core needle biopsy and fineneedle aspiration can aid in the antemortem diagnosis of bovine enzootic lymphosarcoma. Results of fine-needle aspiration of enlarged peripheral lymph nodes were more specific and more predictive for a positive test result than were results of core needle biopsy.