ABSTRACT
RATIONALE: The 5-choice serial reaction time task (5-CSRTT) is a widely used operant task for measuring attention and motor impulsivity in rodents. Training animals in this task requires an extensive period of daily operant sessions. Recently, a self-paced, automated version of this task has been developed for mice, which substantially reduces training time. Whether a similar approach is effective for rats is currently unknown. OBJECTIVE: Here, we tested whether attention and impulsivity can be assessed in rats with a self-paced version of the 5-CSRTT. METHODS: Operant boxes were connected to home-cages with tunnels. Two groups of rats self-paced their training by means of an automated script. The first group of animals was allowed unlimited access (UA) to start trials in the task; for the second group, trial availability was restricted to the first 2.5 h of the dark cycle (TR). Task parameter manipulations, such as variable inter-trial intervals and stimulus durations as well as pharmacological challenges with scopolamine, were tested to validate the task. RESULTS: Self-paced training took less than 1 week. Animals in the UA group showed higher levels of omissions compared with the TR group. In both protocols, variable inter-trial intervals increased impulsivity, and variable stimulus durations decreased attentional performance. Scopolamine affected cognitive performance in the TR group only. CONCLUSIONS: Home-cage-based training of the 5-CSRTT in rats, especially the TR protocol, presents a valid and fast alternative for measuring attention and impulsivity.
Subject(s)
Attention/physiology , Choice Behavior/physiology , Conditioning, Operant/physiology , Housing, Animal , Impulsive Behavior/physiology , Reaction Time/physiology , Animals , Attention/drug effects , Choice Behavior/drug effects , Cholinergic Antagonists/pharmacology , Cognition/drug effects , Cognition/physiology , Conditioning, Operant/drug effects , Impulsive Behavior/drug effects , Male , Rats , Rats, Long-Evans , Reaction Time/drug effects , Scopolamine/pharmacology , Time FactorsABSTRACT
A clinical case of a patient bearing systemic paracoccidioidomycosis with regional ganglionic and oral exposure and later pulmonary involvement is presented. The patient was treated with specific drugs (amphotericin B, itraconazole, sulfamethoxazole-trimethoprim) and followed throughout a 6-year period and eventually died showing an extensive involvement of the central nervous system.
Subject(s)
Central Nervous System Diseases/etiology , Paracoccidioidomycosis/complications , Adult , Anti-Infective Agents/therapeutic use , Antifungal Agents/therapeutic use , Central Nervous System Diseases/diagnosis , Central Nervous System Diseases/drug therapy , Drug Therapy, Combination , Fatal Outcome , Humans , Itraconazole/therapeutic use , Male , Paracoccidioidomycosis/diagnosis , Paracoccidioidomycosis/drug therapy , Trimethoprim/therapeutic use , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic useABSTRACT
In order to investigate the tyrosine phosphorylation of band 3, we performed immunoblotting of intact red cells using anti-phosphotyrosine antibody of 21 patients with sickle cell disorders (11 SS, 5 Sbeta, 5 SC), 7 patients with beta thalassemias (5 beta thal intermedia, 2 deltabeta thal), 10 normal controls, and 1 patient with hereditary spherocytosis. They had not received transfusion for the last 4 months and all were clinically stable. Our results showed an increased tyrosine phosphorylation of two proteins, in the 100 and 80 kD regions, in sickle cell and beta-thalassemic red cells when compared to the normal controls and to the patient with hereditary spherocytosis. Immunoprecipitation of the lysed red cells with anti-band 3 antibody and immunoblotting with anti-phosphotyrosine antibody confirmed that the 100 kD tyrosine phosphorylated protein was band 3. In the sickle cell disease group, the band 3 tyrosine phosphorylation varied from 2- to 10-fold increase compared to control (x +/- SD; SS = 7.8- +/- 2.7-fold; SC = 3.8- +/- 1.3-fold; Sbeta = 5.2- +/- 2.0-fold). It was also higher in the beta-thalassemic group (beta-thal = 4.3- +/- 3.7-fold). There was no significant difference in tyrosine phosphorylation among the various groups tested, except when we compared the phosphorylation in intact red cells of patients with sickle cell anemia and hemoglobinopathy SC (U = 6, P < 0.02). The tyrosine phosphorylation of band 3 was increased in hemoglobinopathies even in the absence of high reticulocyte count. At least two mechanisms might be involved in the increased tyrosine phosphorylation of band 3 in these hemoglobin disorders, probably related to the endogenous reactive oxygen intermediates generated by the abnormal erythrocyte: an inhibition of protein tyrosine phosphatase activity or an activation of the protein tyrosine kinase p72syk.
