[BMI changes in adolescents and adults women between pregnancy and pospartum]. / Cambios en el índice de masa corporal en adolescentes y adultas entre el embarazo y el posparto.

Te aim of the study was to evaluate pregnancy nutritional consequences in adolescent pregnant women and to identify factors which increase risk of an adverse postpartum nutritional result. We conducted a prospective cohort study in 742 adolescent and 779 adult pregnant women in Guatemala, Dominican Republic and Uruguay, assessing demographic, social, obstetric, weight gain and BMI at first prenatal control, and 4 +/- 1 month postpartum. BMI in adults was classified according to WHO recommendations and NCHS/WHO in adolescents. We assessed changes of BMI between the beginning and postpartum time and a logistic model analysis was applied about the risk of having low BMI at postpartum time. At the beginning of pregnancy the prevalence of low weight was higher in adolescent group and the overweight and obesity higher in adults (p < 0.001). Weight gain was significantly higher in adolescents at same nutritional BMI, except for low weighted. Adolescents had a significant change in their BMI at postpartum time, showing a tendency to increase weight and a higher prevalence of overweight and obesity (p < 0.001). Higher risk of low BMI in postpartum was associated with low prenatal BMI (OR 25,6, CI 12,6 - 52), adolescence (OR 3,3 CI 1,6 - 6,6) and gestational weight gain < 300 g. per week (OR 1,4 CI 1,1 - 3,9). In conclusion adolescent nutritional status was not damaged after pregnancy. The strongest variable associated with postpartum low BMI was BMI which mothers begin pregnancy as equal of adult mothers.

Functional analysis of bioprosthetic heart valves.

Glutaraldehyde-treated bovine pericardium is used successfully as bioprosthetic material in the manufacturing of heart valves leaflets. The mechanical properties of bovine pericardial aortic valve leaflets seem to influence its mechanical behaviour and the failure mechanisms. In this study the effect of orthotropy on tricuspid bioprosthetic aortic valve was analysed, using a three-dimensional finite element model, during the entire cardiac cycle. Multiaxial tensile tests were also performed to determine the anisotropy of pericardium. Seven different models of the same valve were analysed using different values of mechanical characteristics from one leaflet to another, considering pericardium as an orthotropic material. The results showed that even a small difference between values along the two axes of orthotropy can negatively influence leaflets performance as regard both displacement and stress distribution. Leaflets of bovine pericardium bioprostheses could be manufactured to be similar to natural human heart valves reproducing their well-known anisotropy. In this way it could be possible to improve the manufacturing process, durability and function of pericardial bioprosthetic valves.

[Alkylphenols in the environment: a risk for human health?]. / Presenza di alchilfenoli nell'ambiente: un possibile rischio per la salute umana?

Endocrine Disrupting Chemicals (ECD) are a class of chemical compounds widely utilized for many industrial and civil applications and, consequently, widely diffused in the environment. Due to their chemical-physical characteristics, ECD may interfere with several endocrine functions in humans. Alkylphenols (APs), mainly produced by biodegradation of alkylphenols polyethoxylates surfactants, are a relevant group of ECD, both for their environmental diffusion and demonstrated estrogenic activity. Aim of this paper is to assess the potential risk of exposure to APs for humans, on the basis of the available data in literature concerning APs: environmental levels, accumulation in sediments and biota, toxicological effects on experimental animals.

Specific detection of type III iodothyronine deiodinase protein in chicken cerebellar purkinje cells.

Because iodothyronine deiodinases play a crucial role in the regulation of the available intracellular T(3) concentration, it is important to determine their cellular localization. In brain, the presence of type III iodothyronine deiodinase (D3) seems to be important to maintain homeostasis of T(3) levels. Until now, no cellular localization pattern of the D3 protein was reported in chicken brain. In this study polyclonal antisera were produced against specific peptides corresponding to the D3 amino acid sequence. Their use in immunocytochemistry led to the localization of D3 in the Purkinje cells of the chicken cerebellum. Both preimmune serum as well as the primary antiserum exhausted with the peptide itself were used as negative controls. Extracts of chick cerebellum and liver were made in the presence of Triton X-100 to solubilize the membrane-bound deiodinases. Using these extracts in Western blot analysis, a band of the expected molecular weight ( approximately 30 kDa) could be detected in both tissues. Using a full-length (32)P-labeled type III deiodinase cRNA probe, we identified a single mRNA species in the cerebellum that was of the exact same size as the hepatic control mRNA (+/-2.4 kb). RT-PCR, followed by subcloning and sequence analysis, confirmed the expression of D3 mRNA in the chicken cerebellum. In this study we provide the first evidence of the presence of the D3 protein in a neuronal cell type, namely Purkinje cells, by means of immunocytochemical staining. We were able to detect a protein fragment corresponding to the expected molecular mass (30 kDa) for type III deiodinase by means of Western blot analysis. RT-PCR as well as Northern blot analysis confirmed the presence of D3 mRNA in the cerebellum.