Potential use of cellulose acetate butyrate and pluronic F68® blends in the modulation of the diclofenac sodium release from microspheres

Microspheres were prepared using the emulsion/solvent evaporation method with the aim of obtaining diclofenac sodium (DFS) prolonged release dosage forms. The effects of the drug:polymer ratio and addition of Pluronic F68® to the formulations on drug content, particle size and DFS release rate were evaluated using a 22 factorial design. The DFS encapsulation efficiency (%) and the drug content varied from 40 to 70 % and from 4.5 to 13 mg/100 mg, respectively. The mean particle diameter varied from 720 to 850 μm. The addition of Pluronic F68® to the formulations led to an increase in the roughness of the surface. The differential scanning calorimetry (DSC) and infrared spectroscopy (FTIR) studies indicated the presence of Pluronic F68® in the particles. The statistical analysis revealed that the drug content and the release rate of DFS were significantly increased when 1:4 drug:polymer ratio and Pluronic F68® was used to prepare the microspheres.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Desempenho zootécnico e rendimento de carcaça de frangos de corte suplementados com diferentes probióticos e antimicrobianos - DOI: 10.4025/actascianimsci.v26i1.1897

The objective of study was to evaluate the performance of broiler chickens, submitted to diets containing different additives. It was used 2160 birds distributed in a randomized completely experiment with 6 treatments (T) with 8 repetitions of 45 birds each: T1 without growth promoter, T2 e T3 with antimicrobials, T4, T5 e T6 with probiotics. In the experimental period was evaluated the feed consumption, body weight gain, food conversion and mortality and were calculated the carcass yield, cutting, visceras, factor and cost of production. Significant differences between the treatments were not observed to the majority of the treatments. The birds that received antimicrobial growth promoters showed a best feeding conversion in relation to the birds that received control and probiotic ration. The feeding conversion difference reflected in the production cost.Este estudo teve como objetivo avaliar o desempenho zootécnico de frangos de corte, submetidos a dietas com diferentes aditivos. Foram utilizados 2160 frangos de corte de um dia, distribuídos em um delineamento inteiramente casualizado com 6 tratamentos (T) de 8 repetições com 45 aves cada: T1 sem promotor de crescimento, T2 e T3 com promotor de crescimento antimicrobianos, T4, T5 e T6 com probióticos. Durante o período experimental foram avaliados o consumo de ração, o ganho de peso, a conversão alimentar e a mortalidade e foram calculados, o rendimento de carcaça, de cortes, de vísceras, o fator e os custos de produção. Não foram constatadas diferenças significativas entre os tratamentos para a maioria dos parâmetros avaliados, no entanto a conversão alimentar das aves que receberam a ração com promotores de crescimento antimicrobianos foi melhor do que a das aves que receberam a ração controle e com probióticos. Esta diferença na conversão alimentar se refletiu no custo de produção

Distribution of serotonin 5-HT1A-binding sites in the brainstem and the hypothalamus, and their roles in 5-HT-induced sleep and ingestive behaviors in rock pigeons (Columba livia)

Serotonin 1A receptors (5-HT1ARs), which are widely distributed in the mammalian brain, participate in cognitive and emotional functions. In birds, 5-HT1ARs are expressed in prosencephalic areas involved in visual and cognitive functions. Diverse evidence supports 5-HT1AR-mediated 5-HT-induced ingestive and sleep behaviors in birds. Here, we describe the distribution of 5-HT1ARs in the hypothalamus and brainstem of birds, analyze their potential roles in sleep and ingestive behaviors, and attempt to determine the involvement of auto-/hetero-5-HT1ARs in these behaviors. In 6 pigeons, the anatomical distribution of [3H]8-OH-DPAT binding in the rostral brainstem and hypothalamus was examined. Ingestive/sleep behaviors were recorded (1 h) in 16 pigeons pretreated with MM77 (a heterosynaptic 5-HT1AR antagonist; 23 or 69 nmol) for 20 min, followed by intracerebroventricular ICV injection of 5-HT (N:8; 150 nmol), 8-OH-DPAT (DPAT, a 5-HT1A,7R agonist, 30 nmol N:8) or vehicle. 5-HT- and DPAT-induced sleep and ingestive behaviors, brainstem 5-HT neuronal density and brain 5-HT content were examined in 12 pigeons, pretreated by ICV with the 5-HT neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) or vehicle (N:6/group). The distribution of brainstem and diencephalic c-Fos immunoreactivity after ICV injection of 5-HT, DPAT or vehicle (N:5/group) into birds provided with or denied access to water is also described. 5-HT1ARs are concentrated in the brainstem 5-HTergic areas and throughout the periventricular hypothalamus, preoptic nuclei and circumventricular organs. 5-HT and DPAT produced a complex c-Fos expression pattern in the 5-HT1AR-enriched preoptic hypothalamus and the circumventricular organs, which are related to drinking and sleep regulation, but modestly affected c-Fos expression in 5-HTergic neurons. The 5-HT-induced ingestivebehaviors and the 5-HT- and DPAT-induced sleep behaviors were reduced by MM77 pretreatment. 5,7-DHT increased sleep per se, decreased tryptophan hydroxylase expression in the raphe nuclei and decreased prosencephalic 5-HT release but failed to affect 5-HT- or DPAT-induced drinking or sleep behavior. 5-HT- and DPAT-induced ingestive and sleep behaviors in pigeons appear to be mediated by heterosynaptic and/or non-somatodendritic presynaptic 5-HT1ARs localized to periventricular diencephalic circuits

Farmacocinética do propofol em nanoemulsão em gatos Pharmacokinetic of propofol in nanoemulsion in cats

Os felinos são deficientes na biotransformação do propofol e os dados em relação à farmacocinética nessa espécie são escassos. O objetivo deste estudo foi determinar o perfil farmacocinético da infusão contínua de propofol em nanoemulsão juntamente com a emulsão lipídica em felinos. Utilizaram-se seis gatos sem raça definida (SRD), adultos, machos, castrados, com peso médio de 4,2±0,8kg, em estudo aleatório e de autocontrole. Os animais receberam 10mg kg-1 min-1 de propofol a 1% em emulsão lipídica (EMU) ou em nanoemulsão (NANO) durante 30 segundos e, imediatamente após, iniciou-se a infusão de 0,3 mg kg-1 min-1 da mesma formulação durante 60 minutos. Após 15 dias, receberam o mesmo tratamento com a formulação oposta. Amostras de 3mL de sangue venoso foram coletadas nos tempos 0 (basal), 2, 5, 10, 15, 30 e 60 minutos de infusão e aos 5, 10, 15, 30, 60, 90, 120, 180, 240, 360, 600 e 1440 minutos após o final da infusão. Os parâmetros farmacocinéticos foram determinados a partir da curva de decaimento da concentração plasmática versus tempo ao final da infusão. A análise estatística foi realizada através de ANOVA-RM com posterior teste t pareado entre os grupos. Não houve diferença entre as formulações em relação a todos os parâmetros. Os volumes de distribuição foram altos com Vdss de 23,23±12,30 litros kg-1 para a nanoemulsão e de 18,12±8,54 litros kg-1 para a emulsão lipídica. Os Cls foram baixos com um Cl central de 22,20±10,83mL kg-1 min-1 para a nanoemulsão e de 23,42±13,50mL kg-1 min-1 para emulsão lipídica. Conclui-se que a farmacocinética do propofol em gatos após infusão contínua caracteriza-se por uma ampla distribuição tecidual e uma lenta eliminação, com possível efeito cumulativo. A formulação em nanoemulsão apresenta características farmacocinéticas semelhantes às da emulsão lipídica.Cats are deficient in the metabolism of propofol and the data on the pharmacokinetics in this species are scarce. The aim of this study was to determine the pharmacokinetic profile of continuous infusion of propofol in lipid emulsion and compare with the nanoemulsion formulation, in cats. Domestic cats, short hair, adults, male, castrated, weighting 4.2±0.8kg in a randomized and self control trial were used. The animals received 10mg kg-1 of 1% propofol in lipid emulsion or nanoemulsion for 30 seconds and immediately after that, a continuous rate infusion of 0.3mg kg-1 min-1 of the same formulation was administered for 60 minutes. After 15 days the cats received the same treatment with the opposite formulation. Samples of 3mL of venous blood were collected by a central venous catheter inserted in the jugular vein at 0 (baseline), 2, 5, 10, 15, 30, and 60 minutes of infusion and at 5, 10, 15, 30, 60, 90, 120, 180, 240, 360, 600 and 1440 minutes after the end of the infusion. The pharmacokinetic parameters were determined from the decay curve of plasma concentration versus time at the end of the infusion. Statistical analysis was performed using RM-ANOVA with subsequent paired t-test between groups. There was no difference between the formulations with respect to all parameters. The volumes of distribution were high with Vdss of 23.23±12.30 liters kg-1 for the nanoemulsion and 18.12±8.54 liters kg-1 for lipid emulsion. The Cls were low with a Cl central to 22.20±10.83mL kg-1 min-1 for the nanoemulsion and 23.42±13.50mL kg-1 min-1 for lipid emulsion. The conclusion is that the pharmacokinetics of propofol in cats after infusion is characterized by a broad tissue distribution and a slow elimination, with possible cumulative effect. The formulation nanoemulsion has pharmacokinetic properties similar to the lipid emulsion