Evaluation of fitness components in strains of Drosophila mulleri carrying different genotypes for an esterase.

Several fitness components in strains of Drosophila mulleri carrying the slow or the fast alleles for the major beta esterase (esterase-4) found in this species, as well as in heterozygous flies in which the slow or fast alleles came from one of the parents, were evaluated. Twelve components were analysed including longevity of both virgins and mated males and females, productivity, viability, including the egg-larva, egg-pupa, egg-imago and pupa-imago periods. These parameters were used to estimate the total fitness for each genotype. The best score was reached by individuals having the Est-4S/Est-4S genotype (scored at 1.000), followed by a fitness value of 0.892 presented by the Est-4F/Est-4S genotype (with the fast allele from maternal origin), 0.863 for the Est-4F/Est-4F and 0.842 for the Est-4S/Est-4Fgenotypes (with Est-4F of maternal origin). These results suggested a higher relative adaptability of the Est-4S/Est-4S genotype followed by the Est-4F/Est-4S hybrid that possessed the allele Est-4S of maternal origin, which was incompatible with predictions of neutral polymorphism.

The distribution of the P-M hybrid dysgenesis system in Drosophila melanogaster strains from Brazil.

Wild-caught flies of Drosophila melanogaster from seven natural populations of extreme regions of Brazil (São Luís, MA; Teresina, PI; Rio Cipó, MG; Maringá, PR; São José do Rio Preto, SP; Joinville, SC; and Porto Alegre, RS) were studied with the purpose of evaluating hybrid dysgenesis due to mobilization of P elements and the regulatory capacity of the strains' cytotypes. Diagnostic crosses were made and the strains classified according to their P-M phenotypes. Four strains were classified as moderate P (MA, MG, PI, and SP), two as Q (PR and RS) and one as M' (SC). Females of southern strains (PR, SC, and RS) presented in A crosses lower degrees of gonadal dysgenesis scores than those from northern strains (MA and PI).

[The functional expectations of valve bioprostheses. I. Physical and histopathological tests for the use of sections of bovine pericardium]. / Expectativa funcional de biopróteses valvulares. I. Testes físicos e histopatológicos para aproveitamento de regiões de pericárdio bovino.

PURPOSE: The heterogenicity of the bovine pericardium sac regarding its elasticity, extensibility and thickness encouraged the work with the purpose to study the different areas of pericardium, mapped according to its position on the heart. METHOD: Ten bovine pericardium sacs previously selected and obtained at the slaughterhouse immediately after the animal slaughter were utilized. The pericardia were sectioned sagittally from the anterior to the posterior portion, thus obtaining two parts, right and left. Two areas were demarcated for each one of them amounting to four regions: A, B, C and D. Each of the four regions was divided into two regions: 1 and 1, amounting to 80 samples. There have been physical tests (shrinkage and mechanical resistance), histopathological studies and statistical analysis were done. RESULTS: The right ventricle area (region D) had the best utilization (21.3%), and then the left ventricle area (region B, 16.2%). The physical tests on the utilized samples showed minimum and maximum values of 0.20 and 0.40 mm for the thickness, 2.0 and 7.0 kgf for force, 1.6 and 4.2 kgf/mm2 for rupture, 18 and 36% for stretching, 15 and 65 for tenacity index and 85 and 87 degrees C for shrinkage. The region D presented histologically and more preserved, either for the collagen fibers or the elastic ones. CONCLUSION: The results of the statistical analysis proved the need to increase the sample size to certify the existence of a sectioning of the pericardium and a more adequate position of the proof body (longitudinal, transversal and oblique) when obtaining the pericardium flap to make the valve bioprosthesis.