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Abstract

Objective

To determine normal CSF electrophoresis patterns in horses, and to determine whether the electrophoretic scans from horses with cervical compression differ from those of neurologically normal horses.

Animals

32 horses assigned to 1 of 2 groups: neurologically normal (n = 18) or cervical compression (n = 14).

Procedure

CSF was collected from 18 neurologically normal horses referred to the Marion duPont Scott Equine Medical Center, and protein electrophoresis was performed to describe the normal equine CSF electrophoretogram. Results of CSF electrophoresis from 14 horses with cervical compression were then compared with results for the neurologically normal horses.

Results

Horses with cervical compression had decreased β-globulin fraction, and 1 or 2 prominent post-β2 peak(s). When the presence of post-β peaks was used as a diagnostic criterion for cervical compression, the test had sensitivity of 71.4% and specificity of 81.8%, The positive and negative predictive values were 83.3 and 69.2%, respectively.

Conclusion and Clinical Implications

Electrophoresis of CSF may be a useful diagnostic aid in evaluation of horses with neurologic disease. (Am J Vet Res 1997;58:939–941)

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine the effects of induction of capacitative Ca2+ entry on tone in equine laminar arteries and veins.

Sample Population—Laminar arteries and veins from 6 adult mixed-breed horses.

Procedure—Arteries and veins were isolated and mounted on small vessel myographs for the measurement of isometric tension. Capacitative Ca2+ entry was induced by incubating the vessels with the specific Ca2+-ATPase inhibitor thapsigargin (100nM) in a Ca2+- free physiologic salt solution. Capacitative Ca2+ entry–associated contractile responses were determined by the subsequent addition of 2mM Ca2+ to the solution bathing the vessels; in some experiments, either the voltage-gated Ca2+ blocker diltiazem (10µM) or the putative capacitative Ca2+ entry inhibitor trifluoromethylphenylimidazole (300µM) was added to the bathing solution 15 minutes prior to a second 2mM Ca2+ exposure. The Sr2+ permeability of the capacitative Ca2+ entry pathway in laminar vessels was assessed by exposing the vessels to 4mM Sr2+ after induction of capacitative Ca2+ entry with thapsigargin.

Results—Induction of capacitative Ca2+ entry elicited robust contractile responses in laminar veins but did not increase tone in laminar arteries. In laminar veins, capacitative Ca2+ entry–induced contractile responses were unaffected by preincubation with diltiazem, attenuated by trifluoromethylphenylimidazole, and were impermeable to Sr2+.

Conclusions and Clinical Relevance—Results indicated that induction of capacitative Ca2+ entry elicits vasoconstriction in equine laminar veins but not in laminar arteries and should therefore be considered a potential mechanism by which selective venoconstriction occurs in horses during the development of acute laminitis. (Am J Vet Res 2005;66:1877–1880)

Full access
in American Journal of Veterinary Research

Summary

Whole-cell lysates and proteinase K-extracted lipopolysaccharide (lps) of 19 strains of the group eugonic fermenter- 4 (ef-4) were analyzed by electrophoresis and protein immunoblotting. These strains were isolated from dog- and cat-bite abscesses in human beings, ferret and human gastric lesions, and cat-lung infections. These strains represent 2 biovar groupings; ef-4a biovars ferment glucose and possess arginine dihydrolase activity, whereas ef-4b biovars do not. Electrophoresis of wholecell lysates could distinguish between these biovars groups. Electrophoresis of lps extracts revealed that all strains of ef-4 possess smooth chemotypes. Two strains of ef-4a reacted weakly in protein immunoblots and revealed distinct lps profiles. These studies suggests that subgroups of ef-4 biovars may exist.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To investigate the effects of poor water quality on hematologic and biochemical analytes in hybrid striped bass.

Animals

Hybrid striped bass (reciprocal cross: female Morone chrysops × male M saxatilis) maintained in 2,000-L tanks with undergravel filters.

Procedure

Fish were acclimated to high ammonia (0.15 mg/L) and nitrate (200 mg/L) concentrations for 6 weeks prior to sample collection. Hematologic and biochemical profiles were determined for these fish and for fish kept under normal conditions (control). Comparisons were made among the 3 water qualities and with reference intervals determined previously.

Results

Significant differences in hematologic and biochemical analytes were observed between fish in the various groups; however, most of the values were within established reference intervals. All values from fish in the high ammonia concentration tank were either within the reference interval or not significantly different from control values. Fish from the high nitrate concentration tank had higher serum creatinine values and lower chloride values than did control fish, and both analytes were substantially outside the reference intervals.

Conclusion

High ammonia concentration of 0.15 mg/L did not affect any of the blood analytes measured. The hypercreatininemia and hypochloremia observed in fish from the 200 mg of nitrate/ml tank were considered to be pathologic changes associated with the high nitrate concentration.

Clinical Relevance

Determining the effects of water quality on hematologic and biochemical values helps to develop clinical pathology as a diagnostic tool in fish. (Am J Vet Res 1997;58:131–135)

Free access
in American Journal of Veterinary Research

Abstract

Objective

To investigate the effect of water temperature on hematologic and biochemical analytes in hybrid striped bass.

Animals

Hybrid striped bass (reciprocal cross; female Morone chrysops × male M saxatilis) maintained in 2,000-L tanks with undergravel filters.

Procedure

Fish were acclimated to 10. 18, 24, and 29 C water for 6 weeks prior to sample collection. Hematologic and serum biochemical profiles were then determined. Values were compared among the various temperatures, and with reference intervals previously determined.

Results

Most values were within or slightly outside the established reference intervals. The following analytes deviated notably from the reference interval: leukocyte, lymphocyte, and monocyte counts were lower than the reference intervals at 10 C; glucose values were lower at 10 and 18 C; calcium values were higher at 10 and 18 C; and total protein, albumin, globulin, and chloride values were higher at 29 C.

Conclusion

Separate reference intervals should be developed for analytes which, because of temperature, deviate notably from the reference interval. Modifications of the established reference intervals, by including fish from varied temperatures, should allow use of one reference interval for analytes, with only slight variation attributable to temperature.

Clinical Relevance

Determining the effects of temperature on the hematologic and biochemical values helps develop clinical pathology as a diagnostic tool in fish. (Am J Vet Res 1997;58:126–130)

Free access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Abstract

Objective—To analyze survival time and identify prognostic factors associated with outcome following discharge in dogs with primary brain tumors treated palliatively.

Design—Prospective case series.

Animals—51 dogs with 5 histopathologic types of brain tumors.

Procedures—Owners with dogs examined from 2004 to 2008 were invited to participate if dogs had CT or MRI evidence of a brain mass that was histopathologically confirmed as a neoplasm upon death, dogs survived for ≥ 48 hours after hospital discharge, and treatments following discharge were limited to administration of prednisone or phenobarbital. Prognostic factors, including signalment, clinical signs (including duration), tumor type, tumor location, degree of peritumoral edema, lesion burden, and prescribed treatment, were evaluated. Survival time was estimated and animal- and tumor-specific variables evaluated as potential prognostic factors.

Results—The median survival time in all dogs was 69 days (95% confidence interval [CI], 18 to 201 days). Multivariate analyses identified neuroanatomic location as the only significant prognostic variable, with the survival time of dogs with infratentorial tumors (n = 18) being significantly shorter (median, 28 days; 95% CI, 19 to 68 days) than survival time of dogs with supratentorial (33) tumors (median, 178 days; 95% CI, 119 to 270 days). Seizures were the most common clinical sign associated with supratentorial tumors (24/33 [73%]) and central vestibular dysfunction with infratentorial tumors (12/18).

Conclusions and Clinical Relevance—Dogs with palliatively treated primary brain tumors, particularly those with tumors in the cerebellum, pons, or medulla, had a poor prognosis. However, dogs with supratentorial tumors had survival times > 3 months.

Full access
in Journal of the American Veterinary Medical Association

Objective

To identify factors affecting the prognosis for survival and athletic use in foals with septic arthritis.

Design

Retrospective study.

Animals

93 foals with septic arthritis.

Procedure

Medical records were reviewed to obtain clinical findings, laboratory test results, radiographic findings, treatment method, and outcome. Race records for Thoroughbreds and Standardbreds were evaluated to determine whether foals subsequently raced and whether they raced successfully.

Results

43 foals had 1 affected joint, 44 foals had multiple affected joints, and number of affected joints was not recorded for 6 foals. The femoropatellar and tarsocrural joints were most commonly affected. Osteomyelitis or degenerative joint disease were detected in 59% (46/78) of foals. Failure of passive transfer, pneumonia, and enteritis were common. Foals were treated with lavage, lavage and intra-articular administration of antibiotics, lavage and arthroscopic debridement with or without partial synovectomy, or lavage and arthrotomy to debride infected bone and systemic administration of antibiotics. Seventy-three foals survived to be discharged from hospital, and approximately a third raced. Isolation of Salmonella spp from synovial fluid was associated with an unfavorable prognosis for survival and multisystem disease was associated with an unfavorable prognosis for survival and ability to race; other variables were not significantly associated with survival and ability to race.

Conclusions and Clinical Relevance

With treatment, the prognosis for survival of foals with septic arthritis was favorable, whereas prognosis for ability to race was unfavorable. Multisystem disease, isolation of Salmonella spp from synovial fluid, involvement of multiple joints, and synovial fluid neutrophil count ≥ 95% at admission may be of prognostic value. (J Am Vet Med Assoc 1999;215:973–977)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the effects of inhibition of Rho-kinase or Src-family protein tyrosine kinases (srcPTK) on agonist-induced contractile responses in equine laminar arteries and veins.

Sample Population—Laminar arteries and veins obtained from 13 adult mixed-breed horses.

Procedures—Laminar vessels were mounted on myographs and exposed to phenylephrine (PE), 5-hydroxytryptamine (5-HT), prostaglandin F (PGF), and endothelin-1 (ET-1) with or without the Rho-kinase inhibitor Y-27632 (10μM), srcPTK inhibitor PP2 (10μM), or a negative control analogue for PP2 (PP3; 10μM).

Results—Responses to PE were reduced by use of Y-27632 in laminar vessels (approx inhibition, 55%). However, Y-27632 reduced responses to 5-HT to a greater degree in veins than in arteries (approx inhibition of 55% and 35%, respectively). The Y-27632 also reduced responses of laminar veins to ET-1 by approximately 40% but had no effect on maximum responses of laminar arteries to ET-1, although a rightward shift in the concentration response curve was evident. Addition of PP2 reduced responses to PE, 5-HT, and PGF in laminar veins by approximately 40%, 60%, and 65%, respectively, compared with responses after the addition of PP3; PP2 had no effect on responses to ET-1. In laminar arteries, PP2 reduced 5-HT–induced contractions by approximately 50% but did not affect responses to PE or ET-1.

Conclusions and Clinical Relevance—Results of the study were consistent with activation of Rho-kinase being important during agonist-induced constriction in laminar vessels, activation of srcPTK being an agonist-dependent event, and more prominent roles for Rhokinase and srcPTK in veins than in arteries.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To determine the effects of the protein kinase C (PKC) inhibitor, Ro-31-8220, on agonist-induced constriction of laminar arteries and veins obtained from horses.

Sample Population—Laminar arteries and veins obtained from 8 adult mixed-breed horses.

Procedures—Laminar arteries and veins were isolated and mounted on small vessel myographs for the measurement of isometric tension. Concentration-response curves were then obtained for the vasoconstrictor agonists phenylephrine, 5-hydroxytryptamine, prostaglandin F, and endothelin-1. All responses were measured with or without the addition of Ro-31-8220 (3μM).

Results—Laminar veins were more sensitive to vasoconstrictor agonists than laminar arteries, and incubation of laminar veins with Ro-31-8220 resulted in significantly smaller agonist-induced contractile responses for all agonists tested. In contrast, Ro-31-8220 had no effect on agonist-induced contractile responses of laminar arteries.

Conclusions and Clinical Relevance—Results of the study were consistent with activation of PKC being confined to agonist-induced contraction of laminar veins isolated from the laminar dermis of horses. Consequently, the possible involvement of PKC in the venoconstriction observed during the development of laminitis is worthy of further investigation.

Full access
in American Journal of Veterinary Research