Search Results

You are looking at 1 - 5 of 5 items for

  • Author or Editor: Dennis Brown x
  • Refine by Access: All Content x
Clear All Modify Search
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine regional and zonal variation in sulfation patterns of chondroitin sulfate in normal equine corneal stroma.

Sample Population—22 normal eyes from 11 horses.

Procedure—Corneas were collected within 24 hours of death from equine necropsy specimens. After papain-chondroitinase digestion of corneal tissue, disaccharides ΔDi4S and ΔDi6S were quantified by use of capillary zone electrophoresis in the superficial, middle, and deep zones of central and peripheral regions of the cornea.

Results—For the 2 regions combined,ΔDi6S/ΔDi4S values were significantly lower in the deep and middle zones, compared with that of the superficial zone. In the central region, deep and middle zones had significantly lower ΔDi6S/ΔDi4S values than the superficial zone did. In the peripheral region, the deep zone had significantly lower ΔDi6S/ΔDi4S values, compared with superficial and middle zones. In the deep zone, the peripheral region had significantly lower ΔDi6S/ΔDi4S values than the central region did.

Conclusion and Clinical Relevance—Distribution of ΔDi6S/ΔDi4S values follows a gradient across the healthy equine cornea, being smallest in the deep and middle zones of the central region and the deep zone of the peripheral region. Regional and zonal differences in the distribution of stromal ΔDi6S and ΔDi4S may influence the role of glycosaminoglycans in health, disease, and wound repair of the equine cornea. (Am J Vet Res 2002;63:143–147)

Full access
in American Journal of Veterinary Research

Summary

The feasibility, safety, and efficacy of a new method of local, sustained-release chemotherapy by use of intralesional cisplatin implants were evaluated in the treatment of oral malignant melanoma. The implant is an injectable viscous gel composed of a protein carrier matrix, a vasoactive modifier, and a chemotherapeutic drug. Twenty dogs with biopsy- proven melanomas were treated at 1- to 2-week intervals by injection with cisplatin implant. Tumors were treated until they resolved or were judged to be unresponsive. In 3 dogs with tumors unresponsive to cisplatin implants, methotrexate implants were used, and in 2 of these dogs, carmustine implants followed the methotrexate. Tumor responses were evaluated by sequential measurements.

Melanomas in 14 (70%) of 20 dogs had a > 50% decrease in volume, and in 11 (55%) of these dogs, had a complete response. Tumors with complete responses received a mean cisplatin dose of 11.7 ± 1.8 mg, delivered in a mean of 2.6 treatments. Two of the dogs with complete response also were treated with methotrexate and carmustine. Implants were well tolerated. Local necrosis, limited to the treatment site, developed in most tumors (17/20) and was associated with tumor response. Systemic toxicosis was minimal; renal insufficiency after cisplatin implants was not evident.

Median survival times of dogs with complete tumor response (51 weeks) was substantially greater than that of dogs without local tumor control (10.5 weeks). Recursive partitioning analysis of variables indicated that mandibular tumors of short duration were associated with a positive outcome. Multivariate linear regression analysis revealed the benefit of a greater number of cisplatin implants in a consistent weekly treatment course. The success of the intralesional chemotherapy indicated that implants are a technically feasible modality for local control of oral melanomas in dogs and provide possible alternative treatment to radiation therapy or surgery.

Free access
in Journal of the American Veterinary Medical Association