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Adriano B L Tort

Publications and source records attributed to Adriano B L Tort.

16 recordsLinked to original sources
PubMed2006

A simple webcam-based approach for the measurement of rodent locomotion and other behavioural parameters.

We hereby describe a simple and inexpensive approach to evaluate the position and locomotion of rodents in an arena. The system is based on webcam registering of animal behaviour with subsequent analysis on customized software. Based on black/white differentiation, it provides rapid evaluation of animal position over a period of time, and can be used in a myriad of behavioural tasks in which locomotion, velocity or place preference are variables of interest. A brief review of the results obtained so far with this system and a discussion of other possible applications in behavioural neuroscience are also included. Such a system can be easily implemented in most laboratories and can significantly reduce the time and costs involved in behavioural analysis, especially in developing countries.

Algorithms↗
PubMed2006

Theoretical insights into the mechanism of action of atypical antipsychotics.

The present work discusses some theoretical mathematical results that can be derived from the theory of receptor binding linked with PET experimental data and presents insights to the understanding of the differences between typical and atypical profile of antipsychotics regarding the generation of extrapyramidal syndrome. The first part of the paper discusses the importance of the drug affinity to dopamine D2 receptors (D2R) and of the therapeutic window of drug concentration for antipsychotic action without EPS, whereas the second part discusses the contribution of the plasma half-life in the time-course of D2R occupancy. Together with current experimental data, we concluded that the key factors leading to an atypical profile would be adequate posology, low affinity of the drug to D2R and/or short plasma half-life.

Animals↗
PubMed2005

S100B and NSE serum concentrations in Machado Joseph disease.

BACKGROUND: NSE and S100B are considered as neuronal and glial peripheral markers of central nervous system pathologies, respectively. We evaluated the potential use of S100B and NSE serum concentrations as peripheral markers of symptomatic patients with Machado Joseph disease (MJD). METHODS: We measured S100B and NSE peripheral concentrations of 22 MJD patients and compared with healthy subjects concentrations. The correlations of both markers with CAG repeat size, age of onset, disease duration, and the scores of the Extended Disability Status Scale of Kurtzke, Unified Parkinson's Disease Rating Scale, and the Montgomery-Asberg depression rating scale were also assessed. RESULTS: S100B serum concentrations between control and MJD subjects were not statistically different, whereas NSE serum concentrations were higher in MJD patients than in control subjects (p=0.00001). S100B presented a moderate correlation with disease duration and depression score, whereas NSE presented a moderate correlation with depression score and a good negative correlation with EDSS score. CONCLUSIONS: Symptomatic MJD patients present increased concentrations of NSE and normal concentrations of S100B in blood.

Adult↗
PubMed2005

S100B and NSE serum levels in patients with Parkinson's disease.

We evaluated S100B protein and neuron-specific enolase (NSE) serum levels in Parkinson's disease (PD) patients and their correlation with the severity of disease. The levels of S100B (P=0.16) and NSE (P=0.39) between PD and controls were similar. However, S100B levels correlated positively with the Hoehn and Yahr scale (r=0.368; P=0.02) and negatively with the Activities of Daily Living (ADL) scale (r=-0.431; P=0.006). Therefore, S100B and NSE may not have a diagnostic role in PD, but S100B may have a potential role as a marker of disease progression. The study of S100B may also contribute to elucidate the controversial role of glial cells in PD.

Aged↗
PubMed2005

Cinnarizine has an atypical antipsychotic profile in animal models of psychosis.

Cinnarizine, a drug known as a calcium channel blocker, is currently used for the treatment of migraine and vertigo. Induction of extrapyramidal signs by cinnarizine has been reported in the elderly, which is related to its moderate antagonistic properties at dopamine D2 receptors, resembling the mechanism of action of most antipsychotic drugs. Despite this effect, cinnarizine has never been tested as a putative antipsychotic drug. Here we evaluate the potential effect of cinnarizine in two pharmacological models of psychosis, namely amphetamine- and MK-801-induced hyperlocomotion, as well as its ability to induce catalepsy. Cinnarizine significantly counteracted MK-801 (0.25 mg/kg) and amphetamine (5mg/kg) locomotor effects at doses as low as 20mg/kg, having no incremental effect at 60 or 180 mg/kg. Regarding side-effects, cinnarizine induced no catalepsy in mice at the effective dose of 20 mg/kg, inducing only mild catalepsy at the doses of 60 and 180 mg/kg. Based on these results and on the antagonist effect of cinnarizine on dopamine D2 receptors, we suggest that it has a potential antipsychotic effect with an atypical profile that should be evaluated clinically.

Amphetamine↗
PubMed2004

Specificity and sensitivity of S100B levels in amniotic fluid for Down syndrome diagnosis.

Down syndrome (DS) is the most common chromosomal abnormality and is associated with an extra copy of the chromosome 21. Although several markers are commonly used during pregnancy for the screening of DS, the definitive diagnosis is based on karyotype after amniocentesis, which is an expensive and laborious analysis. S100B is an astrocyte protein which had its gene mapped to the long arm of chromosome 21. Previous preliminary reports have found increased levels of this protein in the amniotic fluid of DS gestations. Aiming to achieve a simpler and cheaper test then karyotype to perform prenatal diagnosis of DS, here we have extended our previous studies and evaluated the real usefulness of amniotic S100B measurement for prenatal DS diagnosis. We have measured S100B in amniotic fluid of 96 pregnancies with DS and of 50 normal pregnancies. Pregnancies with DS presented significantly higher amniotic fluid S100B levels (M = 1.16 ng/mL; IQ = 0.83/1.78) than normal pregnancies (M = 0.51 ng/mL; IQ = 0.38/0.83) (p < 0.0001). A receiver operating characteristic (ROC) curve was performed to evaluate the sensitivity and specificity of S100B for DS diagnosis, and presented an area under the curve (AUC) of 0.82, indicating that S100B could be a reliable marker of DS. Moreover, values above 1.67 ng/mL were present only in DS fetuses, representing about 30% of affected pregnancies. However, as an overlap of values was observed between normal and DS gestations, we concluded that amniotic S100B alone is not a good test to discard DS diagnosis.

Adult↗
PubMed2004

Guanosine selectively inhibits locomotor stimulation induced by the NMDA antagonist dizocilpine.

Guanosine has been shown to modulate glutamate system by stimulating astrocytic glutamate uptake. Recent evidence suggest that the locomotor effects of NMDA receptor antagonists, an animal model of schizophrenia, is associated with activation of non-NMDA glutamatergic receptors caused by increased glutamate release. The present work was undertaken to evaluate whether guanosine could have influence on the hyperlocomotion induced in mice by dizocilpine (MK-801), a NMDA antagonist. We also evaluated the effect of guanosine on the hyperlocomotion induced by the indirect dopamine agonist amphetamine, and by the non-selective adenosine receptor antagonist caffeine. Guanosine (7.5 mg/kg) produced an attenuation of about 60% on the hyperlocomotion induced by dizocilpine (0.25 mg/kg), whereas it did not affect the hyperlocomotion induced by amphetamine (5 mg/kg) or caffeine (30 mg/kg). Guanosine pre-treatment did not affect total spontaneous locomotion in all experiments. To test neuronal pathway selectivity, we evaluated MK-801 against guanosine in a working memory paradigm (spontaneous alternation task). Guanosine did not reverted the impairment caused by MK-801 in the spontaneous alternation test, and when administered alone also presented an amnesic effect. The results are discussed based on the current hypothesis of locomotor activation induced by the psychoactive drugs studied. Further studies are necessary to evaluate if guanosine could have clinical utility for the treatment of schizophrenia.

Amphetamine↗
PubMed2004

Atypical antipsychotic profile of flunarizine in animal models.

RATIONALE: Flunarizine is known as a calcium channel blocker commonly used in many countries to treat migraine and vertigo. Parkinsonism has been described as one of its side-effects in the elderly, which is in agreement with its recently characterized moderate D2 receptor antagonism. OBJECTIVES: To perform a pre-clinical evaluation of flunarizine as a potential antipsychotic. METHODS: We evaluated the action of orally administered flunarizine in mice against hyperlocomotion induced by amphetamine and dizocilpine (MK-801) as pharmacological models of schizophrenia, induction of catalepsy as a measure for extrapyramidal symptoms and impairment induced by dizocilpine on the delayed alternation task for working memory. RESULTS: Flunarizine robustly inhibited hyperlocomotion induced by both amphetamine and dizocilpine at doses that do not reduce spontaneous locomotion (3-30 mg/kg). Mild catalepsy was observed at 30 mg/kg, being more pronounced at 50 mg/kg and 100 mg/kg. Flunarizine (30 mg/kg) improved dizocilpine-induced impairment on the delayed alternation test. CONCLUSIONS: These results suggest a profile comparable to atypical antipsychotics. The low cost, good tolerability and long half-life (over 2 weeks) of flunarizine are possible advantages for its use as an atypical antipsychotic. These results warrant clinical trials with flunarizine for the treatment of schizophrenia.

Administration, Oral↗
PubMed2003

Influence of anticoagulants on the measurement of S100B protein in blood.

OBJECTIVE: Evaluate anticoagulants influence on plasma S100B levels. DESIGN AND METHODS: Blood were collected from 18 healthy adult subjects using: no anticoagulants, EDTA, heparin, and citrate. S100B levels were determined using LIA-mat assay. RESULTS: Heparin plasma and citrate increased plasma S100B levels (p < 0.001), whereas EDTA had no effect (p = 0.24). Heparin plasma samples were highly (r2 = 0.97, p < 0.001), citrate samples were moderately (r2 = 0.49, p < 0.001), and EDTA samples were not (r2 = 0.22, p = 0.059) correlated with serum samples. CONCLUSIONS: When anticoagulant is required, heparin plasma should be the primary choice for measurement of S100 B levels.

Adult↗
PubMed2003

Influence of anticoagulants on the measurement of S100B protein in blood.

OBJECTIVE: Evaluate anticoagulants influence on blood S100B levels. DESIGN AND METHODS: Blood from 18 healthy adult subjects were collected using: no anticoagulants; EDTA; heparin; and citrate. S100B levels were determined using LIA-mat assay. RESULTS: Heparin and citrate increased S100B levels (p<0.001), whereas EDTA had no effect (p=0.24). Heparin samples were highly (r2=0.97, p<0.001), citrate samples were moderately (r2=0.49, p<0.001), and EDTA samples were not (r2=0.22, p=0.059) correlated with serum samples. CONCLUSION: When anticoagulant is required, heparin should be the primary choice.

Adult↗
PubMed2002

Serum S100B levels in patients with lupus erythematosus: preliminary observation.

S100B is an astrocytic calcium-binding protein which has been proposed as a biochemical marker of brain damage or dysfunction in acute and chronic diseases. We investigated whether serum S100B levels could be related to systemic lupus erythematosus (SLE) activity. Patients were grouped as having inactive SLE (ISLE), active SLE without central nervous system (CNS) involvement (ASLE), or active SLE with unequivocal neurologic or psychiatric manifestation (NPSLE). The control group consisted of age- and sex-matched healthy blood donors. S100B levels were determined using a luminescence immunoassay. All SLE groups had higher levels of serum S100B than the control group. Among the SLE groups, significantly higher levels of serum S100B protein were found in the NPSLE group than in the ISLE and ASLE groups, and there was no significant difference in S100B levels between the ISLE and ASLE groups. These preliminary results point to a putative relevance of serum S100B protein levels in SLE patients, specifically concerning CNS involvement present in this disease.

Adult↗