Objective—To determine clinical signs, results of
diagnostic testing, underlying cause, and outcome in
cats with seizures.
Animals—17 cats with seizures.
Procedure—Only those cats in which an underlying
metabolic abnormality causing the seizures had been
identified, diagnostic imaging of the brain and CSF analysis
had been done, or a necropsy had been performed
were included. Seizures were classified as being a result
of metabolic disease, symptomatic epilepsy (ie, epilepsy
resulting from a structural lesion of the brain), or probably
symptomatic epilepsy (ie, epilepsy without any
extracranial or identifiable intracranial disease that is not
suspected to be genetic in origin).
Results—3 cats had seizures associated with an
underlying metabolic disease (hepatic encephalopathy),
7 had symptomatic epilepsy (3 with neoplasia and
4 with meningoencephalitis), and 7 had probably symptomatic
epilepsy. Six of the 7 cats with symptomatic
epilepsy died or were euthanatized within 3 months
after the diagnosis was made, whereas 6 of the 7 cats
with probably symptomatic epilepsy survived for at
least 12 months after the diagnosis was made.
Conclusions and Clinical Relevance—Results suggest
that cats with probably symptomatic epilepsy
may have a good long-term prognosis. (J Am Vet Med
Objective—To identify matrix metalloproteinase (MMP)-2 and -9 in CSF from dogs with intracranial tumors.
Sample—CSF from 55 dogs with intracranial tumors and 37 control dogs.
Procedures—Latent and active MMP-2 and -9 were identified by use of gelatin zymography. The presence of MMPs in the CSF of dogs with intracranial tumors was compared with control dogs that were clinically normal and with dogs that had idiopathic or cryptogenic epilepsy or peripheral vestibular disease. Relationships between MMP-9 and CSF cell counts and protein were also investigated.
Results—Latent MMP-2 was found in CSF samples from all dogs, although active MMP-2 was not detected in any sample. Latent MMP-9 was detected in a subset of dogs with histologically documented intracranial tumors, including meningiomas (2/10), gliomas (3/10), pituitary tumors (1/2), choroid plexus tumors (5/6), and lymphoma (4/4), but was not detected in any control samples. Dogs with tumors were significantly more likely than those without to have detectable MMP-9 in the CSF, and the presence of MMP-9 was associated with higher CSF nucleated cell counts and protein concentration.
Conclusions and Clinical Relevance—Latent MMP-9 was detected in most dogs with choroid plexus tumors or lymphoma but in a smaller percentage of dogs with meningiomas, gliomas, or pituitary tumors. Detection of MMP in CSF may prove useful as a marker of intracranial neoplasia or possibly to monitor response of tumors to therapeutic intervention.
Objective—To isolate and characterize neural stem and progenitor cell populations in the brain of adult dogs.
Animals—7 healthy adult dogs.
Procedures—Dogs (age, 10 to 60 months) were euthanized for reasons unrelated to the study. The subventricular zone (SVZ) adjacent to the lateral ventricles and subgranular zone (SGZ) of the hippocampus were isolated and used to generate single cell suspensions for nonadherent culture. The resulting primary neurospheres were serially passaged to assess self-renewal capacity. Neurospheres were differentiated by the withdrawal of growth factors and the addition of serum. Differentiated and undifferentiated neurospheres were analyzed via reverse transcriptase PCR assay or immunocytochemical staining for markers of pluripotency and neural lineage.
Results—Neurospheres were generated from the SVZ and SGZ in all dogs. The SVZ generated more primary neurospheres than did the SGZ. Serial passage was successful, although few neurospheres could be generated after the fifth passage. Undifferentiated neurospheres were positive for SOX2, nestin, and glial fibrillary acidic protein (GFAP) and negative for OCT4 and NANOG. After differentiation, GFAP, neuronal class III β-tubulin, and 2′, 3′-cyclic nucleotide 3′-phosphodiesterase–positive progeny were noted migrating out of the neurospheres.
Conclusions and Clinical Relevance—Results suggested the persistence of SOX2-positive, nestin-positive, GFAP-positive, OCT4-negative, and NANOG-negative neural progenitor cells in the SVZ and SGZ regions of mature canine brains, which are capable of producing multiple cell lineages. This study may serve as a basis for future studies investigating the role of these cells in various disease processes, such as neoplasia, or for regenerative purposes.
To investigate the feasibility and pharmacokinetics of cytarabine delivery as a subcutaneous continuous-rate infusion with the Omnipod system.
6 client-owned dogs diagnosed with meningoencephalomyelitis of unknown etiology were enrolled through the North Carolina State University Veterinary Hospital.
Cytarabine was delivered at a rate of 50 mg/m2/hour as an SC continuous-rate infusion over 8 hours using the Omnipod system. Plasma samples were collected at 0, 4, 6, 8, 10, 12, and 14 hours after initiation of the infusion. Plasma cytarabine concentrations were measured by high-pressure liquid chromatography. A nonlinear mixed-effects approach generated population pharmacokinetic parameter estimates.
The mean peak plasma concentration (Cmax) was 7,510 ng/mL (range, 5,040 to 9,690 ng/mL; SD, 1,912.41 ng/mL), average time to Cmax was 7 hours (range, 4 to 8 hours; SD, 1.67 hours), terminal half-life was 1.13 hours (SD, 0.29 hour), and the mean area under the curve was 52,996.82 hours X μg/mL (range, 35,963.67 to 71,848.37 hours X μg/mL; SD, 12,960.90 hours X μg/mL). Cmax concentrations for all dogs were more than 1,000 ng/mL (1.0 μg/mL) at the 4-, 6-, 8-, and 10-hour time points.
An SC continuous-rate infusion of cytarabine via the Omnipod system is feasible in dogs and was able to achieve a steady-state concentration of more than 1 μg/mL 4 to 10 hours postinitiation of cytarabine and a Cmax of 7,510 ng/mL (range, 5,040 to 9,690 ng/mL; SD, 1,912.41 ng/mL). These are comparable to values reported previously with IV continuous-rate infusion administration in healthy research Beagles and dogs with meningoencephalomyelitis of unknown etiology.