Search Results

You are looking at 71 - 80 of 981 items for :

  • Refine by Access: All Content x
Clear All
Full access
in Journal of the American Veterinary Medical Association

was approved by the research committee of the Veterinary Society of Surgical Oncology. Participating members of the Veterinary Society of Surgical Oncology were asked to search their medical record databases for cats with a histopathologic diagnosis of

Full access
in Journal of the American Veterinary Medical Association

dogs was accomplished by soliciting participation via veterinarians (veterinary oncologists) and owners. Samples were submitted from the Washington State University College of Veterinary Medicine; Veterinary Oncology Services PLLC, Hopewell Junction, NY

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To examine bicarbonate (HCO3 ) secretion ex vivo in the equine large colon to determine any differences between the right dorsal colon (RDC) and right ventral colon (RVC). The effect of phenylbutazone (PBZ) on HCO3 secretion was examined in the RDC.

ANIMALS

14 healthy horses.

PROCEDURES

In anesthetized horses (n = 10), segments of mucosa from RDC and RVC were harvested to measure HCO3 secretion ex vivo with the pH Stat method. The effect of PBZ on HCO3 secretion in the RDC was studied in 4 additional horses.

RESULTS

Three distinct mechanisms of HCO3 secretion previously described in a murine model were confirmed in the equine colon. The RDC had a greater capacity for electrogenic, Cl-independent HCO3 secretion than the RVC (P = 0.04). In the RDC, all HCO3 secretion was decreased by PBZ (P < 0.02) but was not studied in the RVC because of low baseline secretion.

CLINICAL RELEVANCE

Secretion of HCO3 by the RDC could play a pivotal role in equine colon physiology, because intense microbial fermentation in this site could require HCO3 secretion to buffer short-chain fatty acids. Inhibition of this secretion by PBZ could interfere with mucosal buffering and predispose to changes associated with right dorsal colitis.

Open access
in American Journal of Veterinary Research

In recent years, extracellular vesicles (EVs) have emerged as prominent mediators of the homeostasis, repair, and regeneration of musculoskeletal tissues including bone, skeletal muscle, and cartilage. Accordingly, the therapeutic potential of EVs for regenerative medicine applications has not gone unnoticed. The use of EVs for the treatment of musculoskeletal injury and disease in veterinary species is a nascent but rapidly expanding area of research. Recent studies in this area have demonstrated the safety and feasibility of EV products in dogs and horses. While early clinical responses to EV-based therapeutics in companion animals have been favorable, more rigorously designed, sufficiently powered, and placebo-controlled clinical trials are required to fully elucidate the clinical benefits and best-use scenarios for EV therapeutics in veterinary medicine. Additionally, clinical translation of EV-based therapeutics will require Good Manufacturing Practice–compliant methods to scale up and purify EV products. Despite these challenges, EVs hold great promise in the regenerative medicine landscape, particularly in the treatment of musculoskeletal injury and disease in companion animals.

Open access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

Right dorsal colitis causes chronic colic associated with long-term treatment with nonsteroidal antiinflammatory drugs (NSAIDs). This study was designed to determine if NSAIDs could inhibit anion transporters that protect against intestinal mucosal injury in other species.

ANIMALS

20 healthy horses.

METHODS

The effects of indomethacin (INDO) and firocoxib (FIR), on short-circuit current (Isc) in mucosa from the right dorsal colon (RDC) and right ventral colon (RVC) were measured in Ussing chambers by standard electrophysiological techniques. Immunohistochemical methods were used to detect apoptosis (caspase-3) with these NSAIDs and phenylbutazone (PBZ) and to locate the NKCC1 transporter.

RESULTS

The Isc in RDC and RVC incubated with INDO or FIR was increased almost 3-fold (P < .0001) by prostaglandin E2 (PGE2) through a system inhibited by loop diuretics (P < .0001). Although these findings and anion replacement studies were consistent with anion secretion, the RDC also displayed an Isc response suggestive of a unique transporter apparently absent in RVC or NSAID-free solutions. In RDC, FIR, INDO, and PBZ induced apoptosis in the lower half of crypts. However, significant differences in apoptotic index were recorded in the RDC between NSAID-treated and control tissues (no NSAID).

CLINICAL RELEVANCE

The effects of NSAIDs on Isc were consistent with reduced anion secretion, which could represent the pharmacological equivalent of the transport failure responsible for Cystic Fibrosis (CF) in other species. Failure of anion secretion could interfere with buffering acid from intraluminal fermentation, which could suggest a treatment target for right dorsal colitis.

Open access
in American Journal of Veterinary Research

Summary

Nine dogs with intermediate- or high-grade lymphoma were prospectively entered into a protocol to be given a total of 15 weekly doses of doxorubicin (10 mg/m2 of body surface, iv) in an attempt to eliminate all clinical evidence of neoplasia, with minimal risk of drug toxicity. Eight of these dogs did not complete the protocol because of progression of the disease. The median number of doses administered to dogs that developed progressive disease before the regimen was completed was 5 (range, 2 to 9). Seven dogs achieved partial (n = 5) or complete (n = 2) remission, with median duration of 14 days (range, 7 to 231 days). The dog that was given all 15 weekly treatments remained in complete remission for 231 days. Complete remission that lasted for 14 days was observed in another dog. Toxicosis developed in 3 dogs; signs of toxicosis were generally mild and included colitis (n = 1), vomiting (n = 1), neutropenia (n = 1), and lethargy (n = 1). The lowest neutrophil count (1,876 cells/μl) was seen in one dog after 7 doses of doxorubicin were given. Doxorubicin at dosage of 10 mg/m2/wk appears to be safe, but is generally ineffective for treatment of lymphoma.

Free access
in Journal of the American Veterinary Medical Association

Summary

Analogues of a melanocyte-stimulating hormone (α-msh) have been documented to be effective in inducing integumental melanogenesis in several species. These melanotropin analogues are more potent than the natural hormone and have prolonged biological activity, without apparent teratogenic or other toxic effects, at least in rodents. In a pilot study, a cyclic α-msh analogue, Ac-[Nle 4 , Asp 5 , D _ -Phe 7 , Lys 10 ] α-msh 4-10-NH2, was administered sc to a dog at a dose of 1 mg of analogue in 1 ml of 0.9 % NaCl for 3 weeks, without noticeable adverse effects. There was gradual and extensive darkening of the coat, which originally was predominantly tan, with tips of black. Initially, the darkening involved face and extremities, then gradually expanded to include the trunk and tail hair. Visual pigmentation peaked approximately 2 months after injections were completed. As new hair growth continued subsequent to the injections, the original tan color appeared at the proximal end of the hair shaft, leaving a dark terminal band on all affected hairs. These observations clearly indicated that follicular melanogenesis can be induced in dogs by treatment with a melanotropic peptide.

Free access
in American Journal of Veterinary Research

Summary

Serum α1-acid glycoprotein (α1 ag) concentrations were determined in 55 dogs with previously untreated, histologically confirmed, high-grade lymphoblastic lymphoma, and in 34 dogs with histologically confirmed nonhematopoietic malignancies (13 dogs with carcinomas and 21 dogs with sarcomas). Serum concentrations were again determined in 32 dogs with lymphoma that were in complete remission 3 weeks after 1 dose of doxorubicin (30 mg/m2 of body surface, iv) and in 22 dogs that were still in complete remission 3 weeks after a fourth dose of doxorubicin. For comparison, serum α1 ag concentrations were measured in 19 clinically normal (control) dogs of similar weight and age. Eight of the control dogs were given 1 dose of doxorubicin (30 mg/m2, iv), and serum α1 ag concentrations were measured 3 weeks later.

In control dogs, mean serum α1 ag concentration after treatment with doxorubicin was not significantly different from mean concentration before treatment. Mean α1 ag concentrations in untreated dogs with lymphoma, in dogs with sarcomas, and in dogs with carcinomas were all significantly higher than mean concentration for untreated control dogs. In addition, the mean concentration for dogs with osteosarcomas was significantly higher than mean concentration for untreated control dogs. There were no significant differences in mean serum α1 ag concentrations among dogs with different clinical stages of lymphoma (stage IIIa, stage IVa, stage Va). However, mean serum α1 ag concentrations were were significantly increased for dogs with stages IIIa,, IVa, and Va lymphoma, compared with mean concentration for untreated control dogs. Mean serum α1 ag concentrations were significantly decreased in dogs with lymphoma that were in complete remission after either 1 or 4 doses of doxorubicin, compared with mean concentration in dogs with lymphoma that had not been treated.

Free access
in Journal of the American Veterinary Medical Association