Dantrolene e células-tronco mesenquimais promovem melhora funcional em ratos Wistar com trauma espinhal agudo / Dantrolene and mesenchymal stem cells promote functional improvement in Wistar rats with spinal cord injury

Objetivou-se avaliar o efeito do dantrolene (DAN) e das células-tronco mesenquimais (CTM) no trauma espinhal agudo (TEA). Sessenta ratos Wistar foram divididos nos grupos CTM, DAN + CTM, DAN, trauma e placebo (TP) e sem trauma e placebo (STP). Realizou-se laminectomia de T12 em todos os grupos, seguida de TEA contusivo ∕ compressivo, com exceção do grupo STP. Uma hora depois, os grupos DAN + CTM e DAN receberam 10mg/kg de DAN. Após sete dias os grupos CTM e DAN + CTM receberam 1x106 células, por via intravenosa. Testes comportamentais foram realizados para avaliar a recuperação funcional durante 28 dias. Os animais traumatizados apresentaram paraplegia. Houve melhora funcional significativa nos grupos tratados com CTM, DAN ou associação DAN + CTM em comparação ao grupo TP (p<0,05). Conclui-se que o DAN e as CTM para tratamento de TEA em ratos apresentam efeitos neuroprotetores e promovem melhora neurológica funcional.(AU)

This study aimed to evaluate the effects of dantrolene (DAN) and mesenchymal stem cells (MSCs) in acute spinal cord injury (SCI). Sixty Wistar rats were divided into groups MSCs, MSCs + DAN, DAN, trauma and placebo (TP) and no trauma and placebo (STP). Laminectomy was performed at T12 level in all animals, followed by a weight-drop model of SCI, except for the STP group. An hour later, the MSCs + DAN and DAN groups received 10mg/kg of DAN. After seven days, the MSCs and MSCs + DAN groups received 1x106 cells intravenously. Behavioral tests were performed to assess functional recovery for 28 days. Traumatized animals showed paraplegia. There was a significant improvement in groups MSCs, DAN and MSCs + DAN compared to TP (p<0.05). It was concluded that DAN and MSCs for the treatment of SCI in rats have neuroprotection effect and promote functional neurological improvement.(AU)

Risk factors for cluster seizures in canine idiopathic epilepsy.

Cluster seizures (CS), two or more seizures within a 24-hour period, are reported in 38-77% of dogs with idiopathic epilepsy (IE). Negative outcomes associated with CS include a reduced likelihood of achieving seizure freedom, decreased survival time and increased likelihood of euthanasia. Previous studies have found factors including breed, sex and neuter status are associated with CS in dogs with IE; however, only one UK study in a multi-breed study of CS in IE patients exists to the author's knowledge, and thus further data is required to confirm these results. Data from 384 dogs treated at a multi-breed canine specific epilepsy clinic were retrospectively collected from electronic patient records. 384 dogs were included in the study, of which nearly half had a history of CS (49.1%). Dogs with a history of CS had a younger age at onset than those without (p = 0.033). In a multivariate model, three variables predicted risk of CS: a history of status epilepticus (p = 0.047), age at seizure onset (p = 0.066) and breed (German Shepherd Dog) (p < 0.001). Dogs with a history of status epilepticus and dogs with an older age at seizure onset were less likely to be affected by cluster seizures. German Shepherd Dogs (71% experiencing CS) were significantly more likely to suffer from CS compared to Labrador Retrievers (25%) (p < 0.001). There was no association between sex, neuter status, body size and CS. Further studies into the pathophysiology and genetics of CS are required to further understand this phenomenon.

Clinical risk factors associated with anti-epileptic drug responsiveness in canine epilepsy.

The nature and occurrence of remission, and conversely, pharmacoresistance following epilepsy treatment is still not fully understood in human or veterinary medicine. As such, predicting which patients will have good or poor treatment outcomes is imprecise, impeding patient management. In the present study, we use a naturally occurring animal model of pharmacoresistant epilepsy to investigate clinical risk factors associated with treatment outcome. Dogs with idiopathic epilepsy, for which no underlying cause was identified, were treated at a canine epilepsy clinic and monitored following discharge from a small animal referral hospital. Clinical data was gained via standardised owner questionnaires and longitudinal follow up data was gained via telephone interview with the dogs' owners. At follow up, 14% of treated dogs were in seizure-free remission. Dogs that did not achieve remission were more likely to be male, and to have previously experienced cluster seizures. Seizure frequency or the total number of seizures prior to treatment were not significant predictors of pharmacoresistance, demonstrating that seizure density, that is, the temporal pattern of seizure activity, is a more influential predictor of pharmacoresistance. These results are in line with clinical studies of human epilepsy, and experimental rodent models of epilepsy, that patients experiencing episodes of high seizure density (cluster seizures), not just a high seizure frequency pre-treatment, are at an increased risk of drug-refractoriness. These data provide further evidence that the dog could be a useful naturally occurring epilepsy model in the study of pharmacoresistant epilepsy.

Head trauma as a possible cause of central diabetes insipidus in a cat.

A 13-month-old female domestic shorthair cat presented with a 10-month history of polyuria and polydipsia that began after having been hit by a car. Neurological examination revealed visual deficits and an absent bilateral menace response. Hematological and serum biochemical analyses were within reference values, but hyposthenuria was identified. Failure to concentrate urine during the water deprivation test followed by an increase in urine specific gravity after administration of synthetic antidiuretic hormone (ADH) suggested a diagnosis of central diabetes insipidus. Subcutaneous or oral administration of synthetic ADH was effective in central diabetes insipidus treatment during the 19-month follow-up.