Marfan syndrome is an autosomal dominant disease of connective tissue caused by mutations in the fibrillin-1 encoding gene FBN1. Patients present cardiovascular, ocular and skeletal manifestations, and although being fully penetrant, MFS is characterized by a wide clinical variability both within and between families. Here we describe a new mouse model of MFS that recapitulates the clinical heterogeneity of the syndrome in humans. Heterozygotes for the mutant Fbn1 allele mgΔloxPneo, carrying the same internal deletion of exons 19–24 as the mgΔ mouse model, present defective microfibrillar deposition, emphysema, deterioration of aortic wall and kyphosis. However, the onset of a clinical phenotypes is earlier in the 129/Sv than in C57BL/6 background, indicating the existence of genetic modifiers of MFS between these two mouse strains. In addition, we characterized a wide clinical variability within the 129/Sv congenic heterozygotes, suggesting involvement of epigenetic factors in disease severity. Finally, we show a strong negative correlation between overall levels of Fbn1 expression and the severity of the phenotypes, corroborating the suggested protective role of normal fibrillin-1 in MFS pathogenesis, and supporting the development of therapies based on increasing Fbn1 expression.

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Embryonic stem cells are totipotent cells derived from the inner cell mass of blastocysts. Recently, the development of appropriate culture conditions for the differentiation of these cells into specific cell types has permitted their use as potential therapeutic agents for several diseases. In addition, manipulation of their genome in vitro allows the creation of animal models of human genetic diseases and for the study of gene function in vivo. We report the establishment of new lines of murine embryonic stem cells from preimplantation stage embryos of 129/Sv mice. Most of these cells had a normal karyotype and an XY sex chromosome composition. The pluripotent properties of the cell lines obtained were analyzed on the basis of their alkaline phosphatase activity and their capacity to form complex embryoid bodies with rhythmically contracting cardiomyocytes. Two lines, USP-1 and USP-3, with the best in vitro characteristics of pluripotency were used in chimera-generating experiments. The capacity to contribute to the germ line was demonstrated by the USP-1 cell line. This cell line is currently being used to generate mouse models of human diseases.

-The objective of this study was to evaluate the effects of egg yolk and seminal plasma on the viability of cryopreserved goat semen. To this end, four fertile Saanen bucks, aged between 10 months and 1 year, and weighing 18 to 25 kg, were used. Semen was collected from each buck by the artificial vagina method at the end of breeding season (JuneJuly). The extender used was the yolk citrate, which was split into two equal aliquots: 5% egg yolk (2.5 mL egg yolk: 47.5 mL citrate solution) were added to one of the samples and 10% egg yolk (5.0 mL egg yolk: 45.0 mL citrate solution) were added to another. The sperm motility and vigor after thawing and post thermal resistance test (TRT) were evaluated and the data were subjected to analysis of variance and means were compared by the F test at 5.0% probability. The observed values for motility and vigor after thawing and post thermal resistance test (TRT), fast and slow, according to the presence of seminal plasma and egg yolk percentage were: 5% egg yolk with plasma (25.0% and 3.3; 1.60% and 0.7; 12.36% and 1.6, respectively); 5% egg yolk without plasma (23.61% and 3.1; 1.25% and 0.2; 9.93% and 1.3, respectively); 10% egg yolk with plasma (30.8% and 3.3; 4.4% and 1.9; 19.5% and 2.7, respectively); and 10% egg yolk without plasma (13.4% and 2.5; 4.1% and 0.5; 17.0% and 1.0, respectively). There were significant differences between the analyzed data in relation to semen with or without plasma at different percentages of egg yolk, and the group that presented the best results was 10% egg yolk citrate in extender with plasma. The presence of seminal plasma and higher concentration of egg yolk in extender provide a higher viability of cryopreserved goat semen.

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The objective of this study was to investigate the relationship among functional traits (age at first calving (AFC), calving interval (CI), reproductive efficiency (RE), total milk yield (TMY), and lactation period (LP)) in Red Sindhi breed through multivariate techniques. For this goal, performance data provided by the Brazilian Association of Zebu Breeders related to 560 Red Sindhi dairy cattle from 28 different herds in Brazil, born in the period from 1987 to 2011, were used. Principal component analysis with correlation matrix was used to find the relationship among AFC, CI, RE, TMY, and LP. It was found that for all functional traits, first 3 principal components explained more than 90% of the total variation. Clustering analysis was performed based on Tocher method, and results showed physiological relationships among functional traits. By cluster analysis, twelve different groups were generated from the pool of Sindhi herds analyzed, with a great homogeneity among females for the traits evaluated and only few females generating separate groups. Four hundred and twenty-nine females were clustered in one group, representing 76.60% of the genotypes. Total milk yield (TMY) showed 71.92% of the total variation, and age at first calving (AFC) contributed with 23.06% of the variation, being the two most important traits for the variability of the data set. In conclusion, the multivariate procedures were effective in generating the correlations among the functional traits, showing that CI is correlated with RE and all these functional traits are related with total milk yield.