Effects of unilateral stereotactic posterior striatotomy on harmaline-induced tremor in rats.

Although long known and the most prevalent movement disorder, pathophysiology of essential tremor (ET) remains controversial. The most accepted hypothesis is that it is caused by a dysfunction of the olivocerebellar system. Vilela Filho et al. [2001; Stereotact Funct Neurosurg 77:149-150], however, reported a patient with unilateral hand ET that was completely relieved after a stroke restricted to the contralateral posterior putamen and suggested that ET could be the clinical manifestation of posterior putamen hyperactivity. The present study was designed to evaluate this hypothesis in the most often used model of ET, harmaline-induced tremor in rats. Fifty-four male Wistar rats were randomly distributed into three groups: experimental (EG), surgical control (SCG), and pharmacological control (PCG) groups. EG animals underwent stereotactic unilateral posterior striatotomy. SCG rats underwent sham lesion at the same target. PCG served exclusively as controls for harmaline effects. All animals received, postoperatively, intraperitoneal harmaline, and the induced tremor was video-recorded for later evaluation by a blind observer. Thirteen animals were excluded from the study. Limb tremor was reduced ipsilaterally to the operation in 20 of 21 rats of EG and in two of nine of SCG, being asymmetric in one of 10 of PCG rats. Comparisons between EG × SCG and EG × PCG were statistically significant, but not between SCG × PCG. Limb tremor reduction was greater in anterior than in posterior paws. Lateral lesions yielded better results than medial lesions. These results suggest that the posterior striatum is involved with harmaline-induced tremor in rats and support the hypothesis presented.

A clinical trial to assess the use of sodium hypochlorite and oxytetracycline on the healing of digital dermatitis lesions in cattle.

The increased frequency of diseases, especially those of the hoof, cause economic losses, such as premature culling of affected animals, decreased milk production, weight loss, reduced fertility, and the high costs of treatment. A great variety of hoof conditions may affect cattle, one of them is digital dermatitis. These conditions are probably due to multiple factorial diseases and present with similar clinical signs. Bovine lameness is typically treated by foot trimming and debridment of the lesions, coupled when necessary with systemic antibiotics and therapeutic footbaths, which results in a clinical cure in the majority of the cases. The objective of this study was to evaluate the topical action of sodium hypochlorite associated with the systemic use of oxytetracycline for the treatment of wounds clinically diagnosed as bovine digital dermatitis. One hundred and twenty Holstein cattle varying ages from 1 to 9 y and presenting the clinical signs of digital dermatitis, were used in this study. Group 1 (G1) received topical treatment with a 1% sodium hypochlorite footbath twice a day for 30 d and 4 treatments of parenteral oxytetracycline (10 mg/kg bodyweight, IM, q48h). Group 2 (G2) received only the topical treatment with 1% sodium hypochlorite, as described for G1. Group 3 (G3) received only with parenteral oxytetracycline, as described for G1. Group 4 (G4) was treated exclusively with a dicloro divynil pirrolidona, ortoiododimetil, para-nitofenil-fosforotioato in a vegetal tar-based ointment, immediately after the surgery. After 45 d, the recovery rates were as follows: G1, 86.67%; G2, 73.33%; G3, 56.67%; and G4, 50%. The surgical treatment of digital dermatitis with subsequent treatment with oxytetracycline systemically and 1% sodium hypochlorite topically was the most effective for the convalescence of cattle bearing wounds similar to digital dermatitis.