Solvent retention of contemporary commercial dentin bonding agents in a demineralized dentin matrix.

OBJECTIVES: Solvents are ingredients in dentin-bonding agents (DBAs) that are essential to obtain efficient adhesion to dentin under wet-technique bonding protocol. However, an excess of solvents can compromise bonding durability. This study aimed to assess the retention of solvents present in different DBAs after their application to a demineralized dentin matrix. METHODS: Thirty-six specimens of bovine dentin were demineralized for 7 days in 0.5M EDTA and divided into six groups n=6 (Scotchbond primer, Adper Single Bond 2, Excite, AdheSE primer, Prime & Bond NT and Xeno III). These specimens were individually saturated by the systems for 5 min and then kept in vials protected against light exposure. Each specimen was measured using a digital balance and then measured at the following intervals 10, 20, 30 sec, 1, 2 and 5 min thereafter. Data were analyzed by two-way ANOVA and Tukey tests (alfa=.05). RESULTS: There were significant differences evident in Excite, Prime & Bond NT at 2 and 5 min, respectively. There was no significant interaction between materials and time in all experimented time evaluated. The amount of solvent spontaneously evaporated was limited even in acetone-based specimens. CONCLUSIONS: After DBAs are applied, professionals may facilitate their evaporation, since spontaneous evaporation is limited.

In vitro assessment of solvent evaporation from commercial adhesive systems compared to experimental systems.

Solvents should be properly evaporated after application to dental substrates. The aim of this study was to assess the evaporation of commercial, experimental and neat solvents. The tested null hypotheses were that there are no differences in solvent evaporation regardless of its formulation and over time. Evaporation from commercial adhesive systems (Scotchbond Multipurpose Primer, Scotchbond Multipurpose Adhesive, Prime & Bond NT, Multi Bond, Excite, Single Bond 2, Adhese Primer, Adhese Bond, Xeno III A and Xeno III B) and experimental primers (35% HEMA plus 65% acetone or ethanol or water v/v) were compared to neat solvents (acetone, ethanol and water). Samples (10 microL) of these products were dripped into glass containers placed on a digital precision balance. Evaporation was assessed at 0, 5, 10, 15, 30, 60, 120, 300 and 600 s times to calculate mass loss. Data were analyzed statistically by ANOVA and Bonferroni's correction (a=0.05). Acetone-based products exhibited a remarkable capacity to evaporate spontaneously over time. Neat acetone evaporated significantly more than the HEMA-mixtures and the commercial formulations (p<0.05). The incorporation of monomers and other ingredients in the commercial formulations seem to reduce the evaporation capacity. Solvent evaporation was time and material-dependent.

In vitro assessment of solvent evaporation from commercial adhesive systems compared to experimental systems

Solvents should be properly evaporated after application to dental substrates. The aim of this study was to assess the evaporation of commercial, experimental and neat solvents. The tested null hypotheses were that there are no differences in solvent evaporation regardless of its formulation and over time. Evaporation from commercial adhesive systems (Scotchbond Multipurpose Primer, Scotchbond Multipurpose Adhesive, Prime & Bond NT, Multi Bond, Excite, Single Bond 2, Adhese Primer, Adhese Bond, Xeno III A and Xeno III B) and experimental primers (35 percent HEMA plus 65 percent acetone or ethanol or water v/v) were compared to neat solvents (acetone, ethanol and water). Samples (10 µL) of these products were dripped into glass containers placed on a digital precision balance. Evaporation was assessed at 0, 5, 10, 15, 30, 60, 120, 300 and 600 s times to calculate mass loss. Data were analyzed statistically by ANOVA and Bonferroni's correction (a=0.05). Acetone-based products exhibited a remarkable capacity to evaporate spontaneously over time. Neat acetone evaporated significantly more than the HEMA-mixtures and the commercial formulations (p<0.05). The incorporation of monomers and other ingredients in the commercial formulations seem to reduce the evaporation capacity. Solvent evaporation was time and material-dependent.

O solvente deve ser adequadamente evaporado após aplicação ao substratos dentários. O objetivo deste estudo foi avaliar a evaporação de formulações comerciais, primers experimentais e solventes puros. As hipóteses nulas testadas foram de que não há diferenças da quantidade evaporada independentemente do material e tempo. Evaporação dos sistemas adesivos comerciais (Scotchbond multipurpose primer, Scotchbond multipurpose adhesive, Prime & Bond NT, Multi Bond, Excite, Single Bond 2, Adhese Primer, Adhese Bond, Xeno III A e Xeno III B) e primers experimentais (35 por cento HEMA associado com 65 por cento acetona, etanol ou água v/v) foram comparadas a solventes puros (acetona, etanol e água). Amostras (10 µL) de cada produto foram dispensadas em balança de precisão digital. As massas nos tempos 0, 5, 10, 15, 30, 60, 120, 300 e 600 s foram registradas. Os dados foram analisados estatisticamente por ANOVA e Bonferroni (a=0,05). Produtos a base de acetona exibiram maior capacidade de evaporação espontânea ao longo do tempo. Acetona pura evaporou significantemente mais que as misturas de HEMA e formulações comerciais (p<0,05). A incorporação de monômeros e outros ingredientes nas formulações comerciais reduzem a capacidade de evaporação. A evaporação é dependente do produto e do tempo.

An overview of SSR149415, a selective nonpeptide vasopressin V(1b) receptor antagonist for the treatment of stress-related disorders.

Vasopressin (AVP) and corticotropin-releasing factor (CRF) are key mediators in the organism's neuro-adaptive response to stress. Through pituitary and central vasopressin V(1b) receptors, AVP participates in the control of the hypothalamic-pituitary-adrenal axis (HPA) and is involved in various emotional processes. SSR149415 is the first selective, orally active vasopressin V(1b) receptor antagonist yet described. It is a competitive antagonist with nanomolar affinity for animal and human V(1b) receptors and displays a highly selective profile with regard to a large number of receptors or enzymes. In vitro, SSR149415 potently antagonizes functional cellular events associated with V(1b) receptor activation by AVP, such as intracellular Ca(2+) increase or proliferation in various cell systems. Pharmacological studies, performed by measuring ACTH secretion induced by various stimulants such as hormones (AVP or AVP + CRF) or physical stress (restraint or forced swimming stress and dehydration) in conscious rats or mice, confirm the antagonist profile of SSR149415 and its efficacy in normalizing ACTH secretion in vivo. SSR149415 is active by the oral route, at doses from 3 mg/kg, it potentiates CRF effect and displays a long-lasting oral effect in the different models. At 10 mg/kg p.o. its duration of action is longer than 4 h. This molecule also decreases anxiety and exerts marked antidepressant-like activity in several predictive animal models. The anxiolytic effects of SSR149415 have been demonstrated in various Generalized Anxiety Disorders (GAD) models (four-plate, punished drinking, elevated plus-maze, light dark, mouse defense test battery, fear-potentiated startle and social interaction tests). It is as effective as the benzodiazepine diazepam in the acute stress exposure test. SSR149415 has similar efficacy to the reference antidepressant drug, fluoxetine, in acute (forced-swimming) and chronic (chronic mild stress and subordination stress) situations in rodents. SSR149415 also reduces offensive aggression in the resident-intruder model in mice and hamsters. Depending on the model, the minimal effective doses are in the range of 1-10 mg/kg i.p. or 3-10 mg/kg p.o. SSR149415 is devoid of adverse effects on motor activity, sedation, memory or cognitive functions and produces no tachyphylaxis when administered repeatedly. It is well-tolerated in animals and humans and exhibits an adequate ADME profile. Thus, SSR149415 is a new dual anxiolytic/antidepressant compound, which appears to be free of the known side effects of classical anxiolytic/antidepressant drugs. Clinical trials are in progress, they will hopefully demonstrate its therapeutical potential for treating stress-related disorders.

Uso de anestésico local contendo adrenalina ou noradrenalina em cardiopatas e hipertensos / Use of adrenalin and noradrenalin with local anesthetic in patients with cardiac diseases and hypertension

O autor fez um estudo bibliográfico sobre o uso de adrenalina e noradrenalina, contidos nos anestésicos locais, em pacientes com enfermidades cardíacas e hipertensão arterial. Observou que o uso não é contra-indicado a estes pacientes, desde que se tomem cuidados especiais e não se ultrapassem doses máximas recomendadas