Abstract Meat quality is an important factor of economic interest. Among the quality characteristics, tenderness is the most appreciated by consumers. Single nucleotide polymorphisms (SNPs) have been identified in calpain 1 protease, associated with this characteristic. In this context, the aim of the present work was to determine the allelic and genotypic frequencies of the SNPs CAPN1 316 and CAPN1 4751 in Braford cattle. DNA extraction was carried out from 30 samples. Markers were amplified using the polymerase chain reaction and the results were subsequently visualized by electrophoresis on agarose gels. The CAPN1 316 marker shows allelic frequencies of 0.45 for the C allele and 0.55 for the G allele and CAPN1 4751 frequencies were 0.33 for the T allele and 0.67 for the C allele. On the other hand, the genotypic frequencies of the CAPN1 316 marker were 0.20 (CC), 0.30 (GG) and 0.50 (CG), while for the CAPN1 4751 marker the values they were 0.10 (TT), 0.43 (CC) and 0.47 (CT). Samples with lower shear force values presented GG and TT genotype in CAPN1-316 and CAPN1-4751 markers. Furthermore, results indicate that the population studied is in Hardy-Weinberg Equilibrium. All results indicate that this population does not have a genetic predisposition for meat production with greater tenderness.

Resumen La calidad de la carne bovina constituye un importante factor de interés económico. Entre las características de calidad, la terneza es la más apreciada por los consumidores. Se han identificado polimorfismos de nucleótidos únicos (SNPs) en la proteasa calpaína 1 asociadas con dicha característica. En este contexto, el objetivo del presente trabajo fue determinar la frecuencia alélica y genotípica de los SNPs CAPN1-316 y CAPN1-4751 en animales de raza Braford. Se realizó la extracción de ADN a partir de 30 muestras y la amplificación de los marcadores utilizando la reacción en cadena de la polimerasa y los resultados fueron visualizados mediante electroforesis en geles de agarosa. Las frecuencias alélicas para el marcador CAPN1-316 fueron de 0,45 para el alelo C y 0,55 para el alelo G. En el caso del marcador CAPN1-4751 las frecuencias fueron 0,33 para el alelo T y 0,67 para el alelo C. Por otro lado, las frecuencias genotípicas del marcador CAPN1 316 fueron 0,20 (CC), 0,30 (GG) y 0,50 (CG); mientras que para el marcador CAPN1 4751 los valores fueron 0,10 (TT), 0,43 (CC) y 0,47 (CT). Las muestras con menores valores de fuerza de corte presentaron el genotipo GG y TT en los marcadores CAPN1-316 y CAPN1-4751. De acuerdo a la Ley de Hardy-Weinberg, la población estudiada se encuentra en equilibrio. Los resultados indican que esta población no presenta una predisposición genética para la producción de carne con mayor terneza.

Uma das preocupações nos estudos de adesão recai na investigação dos motivos que justificam a permanência dos praticantes em programas de exercícios físicos. Neste sentido, o objetivo da presente investigação foi identificar os grupos (categorias) de motivos que influenciam a permanência de adolescentes, adultos e idosos nos programas de exercícios físicos oferecidos nos Centros de Atividades do Serviço Social do Comércio do Distrito Federal do Brasil. Uma amostra representativa e aleatória de 986 indivíduos de ambos os sexos (15-89 anos) respondeu a um instrumento de coleta de dados para investigar aspectos sócio-demográficos e os motivos de permanência no referido programa. Os resultados revelaram que o bem-estar pessoal (91.9%) foi considerado o principal motivo para a manutenção da prática de exercícios físicos, entre todas as possibilidades existentes, seguido pela prevenção de doenças (82.8%), condicionamento físico (80.7%), empatia com o professor (79.2%), metodologia do trabalho desenvolvido (75.2%) e diversão (73.9%). Enquanto a prescrição médica tem alto potencial para estimular a inserção destes praticantes nos referidos programas, este motivo perde força no sentido de justificar a permanência da prática de exercícios físicos. Deste modo, é possível concluir que o bem-estar pessoal foi considerado o principal motivo alegado pelos participantes dos programas de exercícios físicos oferecidos pelo Serviço Social do Comércio - Brasil.

One of the concerns in the studies of adhesion lies in the investigation of the motives that justify continuation in physical exercise programs. The goal of this study was to identify motives influencing the continuation of adolescents, adults and the elderly in physical education programs offered by the Centers of Activity of Serviço Social do Comércio do Distrito Federal do Brasil. A representative and random sample of 986 individuals (between 15 and 89 years of age) answered a data collection instrument designed to investigate socio-demographic aspects and motives for permanence in the aforementioned program. Results showed personal wellbeing (91.9%) as the major reason for keeping up on practicing followed by prevention of illnesses (82.8%), physical conditioning (80.7%), empathy with the teacher (79.2%), program methodology (75.2%), and entertainment (73.9%). While medical exercise prescription highly influences people's entrance in these programs, it does not explain people's continuance.

The opportunistic bacterium Proteus mirabilis secretes a metalloprotease, ZapA, considered to be one of its virulence factors due to its IgA-degrading activity. However, the substrate specificity of this enzyme has not yet been fully characterized. In the present study we used fluorescent peptides derived from bioactive peptides and the oxidized ß-chain of insulin to determine the enzyme specificity. The bradykinin- and dynorphin-derived peptides were cleaved at the single bonds Phe-Ser and Phe-Leu, with catalytic efficiencies of 291 and 13 mM/s, respectively. Besides confirming already published cleavage sites, a novel cleavage site was determined for the ß-chain of insulin (Val-Asn). Both the natural and the recombinant enzyme displayed the same broad specificity, demonstrated by the presence of hydrophobic, hydrophilic, charged and uncharged amino acid residues at the scissile bonds. Native IgA, however, was resistant to hydrolysis by ZapA.

The protease ZapA, secreted by Proteus mirabilis, has been considered to be a virulence factor of this opportunistic bacterium. The control of its expression requires the use of an appropriate methodology, which until now has not been developed. The present study focused on the replacement of azocasein with fluorogenic substrates, and on the definition of enzyme specificity. Eight fluorogenic substrates were tested, and the peptide Abz-Ala-Phe-Arg-Ser-Ala-Ala-Gln-EDDnp was found to be the most convenient for use as an operational substrate for ZapA. A single peptide bond (Arg-Ser) was cleaved with a Km of 4.6 µM, a k cat of 1.73 s-1, and a catalytic efficiency of 376 (mM s)-1. Another good substrate for ZapA was peptide 6 (Abz-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-Gln-EDDnp) which was cleaved at a single bond (Phe-Ser) with a Km of 13.6 µM, a k cat of 3.96 s-1 and a catalytic efficiency of 291 (mM s)-1. The properties of the amino acids flanking the scissile bonds were also evaluated, and no clear requirement for the amino acid residue at P1 was found, although the enzyme seems to have a preference for a hydrophobic residue at P2.

Field bioassays were used to demonstrate that aggressive behavior of Polybia paulista (Ihering) workers is elicited by alarm pheromones present in the venom reservoirs of nest defenders and that the brood care pheromone (pupal odor) produced by the young inside the nest also plays an important defensive role. Pupal odor was extracted from the surface of pupa bodies with methanol. When bioassayed alone, the pupal odor elicited only attractiveness of workers towards the odor source, but no stinging attacks were observed. However, in the presence of alarm pheromones, the brood care pheromone potentiated the effect caused by the pupal odors, increasing the number of stinging attacks during an action of colony defense. Thus, the presence of pupae within the nest evidently not only releases brood care but also enhances the aggressiveness of workers in P. paulista colonies.

The effect of pheromones and their chemical analogues in honeybee alarm behaviors was studied in observation boxes. Defensive behaviors, as follows: a) attraction to scent source, b) elevation of wings in "V", c) abdomen elevation, d) abdomen elevation and pumping and e) first leg pair elevation had been temporarily registered when the following compounds were presented: isoamyl alcohol, octyl alcohol, benzyl alcohol, n-butyl acetate, n-octyl acetate, isopentyl acetate, benzyl acetate and 2-heptanone. The results were as follows: 1. the bees elicited some characteristic behaviors when chemical alarm messages were presented, 2. agression (stinging) was not completed with any compound tested, probably because there was not a target (visual stimulus), 3. in all situations the attraction to scent source was low, 4. all the behaviors were elicited in a temporarily different way, 5. the compounds that elicited stronger responses and a greater number of the investigated behaviors were: isopentyl acetate, 2-heptanone, octyl acetate and n-octyl alcohol. In all situations, the first behavior response (and the most intense one) was the elevation and pumping the abdomen. This suggests that the chemical message was promptly recognized and then transmitted to each worker. So, the results obtained in the present work, suggest that chemical alarm messages may be recognized by different mechanisms of neural integration.

The present paper aimed at testing the action of non-lyophilized venom of Africanized bees Apis mellifera through topical applications on Diatraea saccharalis egg masses. The CL50, DL50 and the most susceptible age of eggs to the venom topic application were also determined. Three-day-old eggs were the most susceptible to the venom action with CL50 equal to 8.6 mg/ml and DL50 equal to 0.173 mg/mass. The venom loses its action after being stored for 15 days.

The presence of a polydnavirus in the ovary of the microhymenoptera Apanteles galleriae was detected. This wasp parasites the larvae of the wax moth Galleria mellonella. To study the possible viral effects on the total protein of G.mellonella, hemolymph extracts of the ovary calyxes of parasitized A. galleriae were injected into 6th and 7th instar cells of G.mellonella larvae. Protein profiles on polyacrilamide gel electrophoresis containing sodium dodecyl sulfate (SDS-PAGE) of host cell extracts showed a suppression of several protein bands when infection occurred in the 6th instar. However, in the 7th instar, parasitism caused an amplification in the synthesis of most proteins with some changes in the electrophoretic profile.

A comparison among the profiles of molecular exclusion chromatography in Sephadex G 100 column of venoms from Apis mellifera adansonii and Africanized honeybees revealed unique peaks which might be used to identify these populations. The venoms from hybrid populations resulting from the reciprocal mating of Apis mellifera adansonii and Africanized honeybees presented unique peaks, probably resulting from a synergistic effect between the parental genomes. The occurrence of characteristic peaks in venoms of hybrid populations might be used to identify these populations as well as to distinguish them from their parents.