[Nutritional dynamic monitoring during pregnancy: a personalized intervention of prevention]. / Monitoraggio nutrizionale dinamico in gravidanza: intervento di prevenzione personalizzato.

Obesity is an increasing condition spreading out in all of the world, independently by race, sex and age. Obesity in pregnancy represent a risk condition for both mother and her offspring. All of the studies are observational and show intervention strategies on weight gain improvement during gestational period, a current topic, but still controversial. Our study is based on nutritional dynamic monitoring during pregnancy in order to improve health and wellbeing status of both mother and her offspring, through an early and efficacy prevention.

Long-term oral n-acetylcysteine reduces exhaled hydrogen peroxide in stable COPD.

Oxidative stress caused by airway inflammation is increased in chronic obstructive pulmonary disease (COPD) and may account for the progressive deterioration of structure and function of the respiratory tract observed in this disease. Antioxidant defences of the respiratory tract may be overwhelmed by the oxidant burden in COPD and possibly restored with antioxidant therapy. The level of hydrogen peroxide (H(2)O(2)) concentration in exhaled air condensate (EAC) is a valuable tool for assessing and monitoring oxidative stress. This study aimed to verify the effect of 2-month oral N-acetylcysteine (NAC) treatment compared to placebo on the H(2)O(2) content in EAC of 55 clinically stable COPD patients (48 males), mean age 65.93+/-9.3 years. After clinical examination, pulmonary function tests, and collection of EAC for the basal (T0) assay of H(2)O(2), patients were randomly allocated to group A (usual therapy plus oral NAC 600 mg b.i.d. for 2 months) or group B (usual therapy plus placebo b.i.d. for 2 months). H(2)O(2) assay in EAC was repeated at 15 (T15), 30 (T30), and 60 (T60) days after the start of therapy in each group. All patients were non-smokers or ex smokers for at least 5 years and the two groups were comparable in terms of demographic, respiratory function, and EAC data at baseline. The H(2)O(2) level in EAC of group A was significantly decreased at T15 (1.00+/-0.38 SD microM; p=0.003), T30 (0.91+/-0.44 microM; p=0.007), and T60 (0.83+/-0.41 microM; p=0.000) compared to T0 (1.28+/-0.61 microM). No significant decrease in H(2)O(2) of group B was found at any time point. We conclude that oral NAC 600 mg b.i.d. for 2 months rapidly reduces the oxidant burden in airways of stable COPD patients.

Contribution of glycine 146 to a conserved folding module affecting stability and refolding of human glutathione transferase p1-1.

In human glutathione transferase P1-1 (hGSTP1-1) position 146 is occupied by a glycine residue, which is located in a bend of a long loop that together with the alpha6-helix forms a substructure (GST motif II) maintained in all soluble GSTs. In the present study G146A and G146V mutants were generated by site-directed mutagenesis in order to investigate the function played by this conserved residue in folding and stability of hGSTP1-1. Crystallographic analysis of the G146V variant, expressed at the permissive temperature of 25 degrees C, indicates that the mutation causes a substantial change of the backbone conformation because of steric hindrance. Stability measurements indicate that this mutant is inactivated at a temperature as low as 32 degrees C. The structure of the G146A mutant is identical to that of the wild type with the mutated residue having main-chain bond angles in a high energy region of the Ramachandran plot. However even this Gly --> Ala substitution inactivates the enzyme at 37 degrees C. Thermodynamic analysis of all variants confirms, together with previous findings, the critical role played by GST motif II for overall protein stability. Analysis of reactivation in vitro indicates that any mutation of Gly-146 alters the folding pathway by favoring aggregation at 37 degrees C. It is hypothesized that the GST motif II is involved in the nucleation mechanism of the protein and that the substitution of Gly-146 alters this transient substructure. Gly-146 is part of the buried local sequence GXXh(T/S)XXDh (X is any residue and h is a hydrophobic residue), conserved in all GSTs and related proteins that seems to behave as a characteristic structural module important for protein folding and stability.

A novel glutathione transferase from Haemophilus influenzae which has high affinity towards antibiotics.

Cytosolic glutathione transferase (GSTs) are a family of multi-functional proteins which catalyse the conjugation of glutathione (GSH) to a large variety of endogenous and exogenous electrophilic compounds. Much is known about cytosolic mammalian GSTs, however, the presence of GSTs in several aerobic and anaerobic micro-organisms has also been demonstrated. Several findings seem to suggest that bacterial GSTs are involved in processes of biodegradation of xenobiotics, including antibiotics. However, the function played by these enzymes in the bacterial cell still remains to be clarified. At present, it is ill-defined whether bacterial GST can be classified, as in the case of mammalian enzymes, into several distinct classes. Here we report the purification of a GST isoform from Haemophilus influenzae using GSH-affinity chromatography. The purified protein was characterised by immunological and kinetic properties different from other known GSTs. The dissociation constants of chloramphenicol, ampicillin, rifampicin and tetracycline to the purified enzyme were 0.62, 9.06, 4.08 and 1.77 microM, respectively, as determined by following the quenching of the protein intrinsic fluorescence. These values were much lower than those previously determined for the same drugs with other mammalian or bacterial GSTs. The present results indicate that the enzyme purified from H. influenzae is a novel GST isoform well distinguished from other known mammalian or bacterial GSTs.