19 resultados para FARMACOLOGIA VETERINARIA
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Resumo:
Clays are natural materials that have great potential for use as excipients for solid dosage forms. Palygorskite is a type of clay that has hydrophilic properties as well as a large surface area, which could contribute to the dissolution of drugs. Thus, the present study aims to evaluate the use of palygorskite clay, from Piaui (Northeast region of Brazil), as a pharmaceutical excipient for solid dosage forms, using rifampicin and isoniazid as the model drugs. The former is a poorly soluble drug often associated with isoniazid for tuberculosis treatment. Palygorskite was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), particle size, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and specific surface area (BET). The rheological and technological properties of palygorskite were determined and compared to those of talc, magnesium stearate and Aersosil 200. Mixtures between drugs and palygorskite were analyzed by differential scanning calorimetry (DSC), thermogravimetric analysis (TG) combined with thermal analysis (DTA) and Fourier Transform Infrared Spectroscopy (FT-IR), where the results were compared with those of the individual compounds. In addition, dissolution studies of solid dispersions and capsules containing the drugs, mixed with either palygorskite or a mixture of talc and magnesium stearate, were performed. The results showed that palygorskite has small particles with a high surface area. Its rheological characteristics were better than those of others commonly used glidants and lubricants. There was no interaction between palygorskite and the drugs (rifampicin and isoniazid). Among the dispersions studied, the mixture with palygorskite (5%) showed the highest drug dissolution when compared to other excipients. The dissolution of the rifampicin capsules containing palygosrkite was faster in higher concentrations. However, these differences were statistically different only in the first minutes of the dissolution experiment. The dissolution profile of isoniazid was also statistically different on the initial part of the experiment. The formulations prepared with isoniazid and palygorskite showed higher drug dissolution, but it was in descending order of concentration. According to these results, the palygorskite clay used in this study has great potential for application as an excipient for solid dosage forms
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Resumo:
Of all of the genes associated with the development of Diabetes mellitus type 1 (T1D), the largest contribution comes from the genes in the Human Leukocyte Antigen (HLA) region, mostly the class II DR e DQ genes. Specific combinations of alleles DRB1, DQA1 and DQB1 constituting haplotypes, and further, a combination of more than one haplotype, providing multilocus genotypes are associated with susceptibility, protection and neutrality to DM1. Thus, the aim of present study was to verified the association of polymorphisms of HLA genes class II with susceptibility to type 1 diabetes mellitus (T1D). Ninety-two patients with T1D and 100 individuals normoglycemics (NG) aged between 6 and 20 years were studied. Genomic DNA was obtained from peripheral whole blood, collected in EDTA tube, using the extraction kit Illustra Triple Prep®, GE Healthcare. For HLA typing was used DNA LABType system by One Lambda kit applying Luminex® technology to the method of PCRSSO typing reverse. The alleles DRB1*03:01, *04:05, *04:01, *04:02, DQA1*03:01g, *05:01g, DQB1*02:01g, *03:02, the haplotypes DRB1*03:01-DQA1*05:01-DQB1*02:01, DRB1*04:05-DQA1*03:01g-DQB1*03:02, DRB1*04:02-DQA1*03:01g-DQB1*03:02, DRB1*04:01-DQA1*03:01g-DQB1*03:02 and DR3-DQ2/DR4-DQ8 genotype were significantly associated with the chance of developing T1D. The alleles DRB1*11:01, *15:03, *15:01, *13:01, DQA1*01:02, *04:01g, *01:03, DQB1*06:02, *03:01g, *06:03, *04:02, the haplotypes DRB1*11:01-DQA1*05:01-DQB1*03:01, DRB1*13:01-DQA1*01:03-DQB1*06:03 and DRX-DQX/DRX-DQX genotype, formed by other than the DR3-DQ2 or DR4-DQ8 haplotypes, were significantly associated with T1D protection Despite the major racial Brazilian, even at the regional level, these results are similar to the majority of alleles, genotypes and haplotypes of HLA class II-related susceptibility or resistance to T1D, extensively described in the literature for Caucasian population. Children with age at diagnosis less than 5 years of age had significantly higher frequency of the heterozygous genotype DR3-DQ2/DR4-DQ8 compared to children with age at diagnosis than 5 years old. These results also demonstrate strong association of the genetic profile of the class II HLA for this age group, possibly associated with the severity and rapid progression to the onset of T1D. The knowledge of HLA class II genes may be useful in genetic screens that allow the prediction of T1D