Application of Airborne Microorganism Indexes in Offices, Gyms, and Libraries

The determination of microbiological air quality in sporting and working environments requires the quantification of airborne microbial contamination. The number and types of microorganisms, detected in a specific site, offer a useful index for air quality valuation. An assessment of contamination levels was carried out using three evaluation indices for microbiological pollution: the global index of microbiological contamination per cubic meter (GIMC/m3), the index of mesophilic bacterial contamination (IMC), and the amplification index (AI). These indices have the advantage of considering several concomitant factors in the formation of a microbial aerosol. They may also detect the malfunction of an air treatment system due to the increase of microbes in aeraulic ducts, or inside a building compared to the outdoor environment. In addition, they highlight the low efficiency of a ventilation system due to the excessive number of people inside a building or to insufficient air renewal. This study quantified the levels of microorganisms present in the air in different places such as offices, gyms, and libraries. The air contamination was always higher in gyms that in the other places. All examined environments are in Northern Italy

Differential effect of liver cirrhosis on the pregnane X receptor-mediated induction of CYP3A1 and 3A2 in the rat.

Conflicting results have been obtained by clinical studies investigating the effect of liver cirrhosis on enzyme induction. Because ethical concerns do not give consent for methodologically rigorous studies in humans, we addressed this question by examining the effect of the prototypical inducer dexamethasone (DEX) on the pregnane X receptor (PXR)-mediated induction of CYP3A1 and 3A2 in a validated animal model of liver cirrhosis obtained by exposure of rats to carbon tetrachloride. For this purpose, we assessed mRNA levels, protein expressions, and enzymatic activities of both CYP3A enzymes, as well as mRNA and protein expressions of PXR in rat populations rigorously stratified according to the severity of liver insufficiency. Constitutive mRNA and protein expressions of CYP3A1 and CYP3A2 and their basal enzyme activities were not affected by liver dysfunction. DEX treatment markedly increased steady-state mRNA level, protein content, and enzymatic activity of CYP3A1 in healthy and cirrhotic rats, irrespective of the degree of liver dysfunction. On the contrary, the inducing effect of DEX on gene and protein expressions and enzyme activity of CYP3A2 was preserved in moderate liver insufficiency, whereas it was greatly curtailed when liver insufficiency became severe. mRNA and protein expressions of PXR were neither reduced by liver dysfunction nor increased by DEX treatment. These results indicate that even the inducibility of cytochrome P450 isoforms under the transcriptional control of the same nuclear receptor may be differentially affected by cirrhosis and may partly explain why conflicting results were obtained by human studies