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Mutations of rpoB associated with rifampin resistance were studied in 37 multidrug-resistant (MDR) clinical strains ofMycobacterium tuberculosis isolated in Italy. At least one mutated codon was found in each MDR strain. It was always a single-base substitution leading to an amino acid change. Nine differentrpoB alleles, three of which had not been reported before, were found. The relative frequencies of specific mutations in this sample were different from those previously reported from different geographical areas, since 22 strains (59.5%) carried the mutated codon TTG in position 531 (Ser→Leu) and 11 (29.7%) had GAC in position 526 (His→Asp).

Work-related stress is a known occupational hazard, with a putative role on the development of cardiovascular diseases (CVD). Although several investigations have explored the association in various workplace scenarios, none have focused on the airport flight logistic support personnel, a transportation business of crucial importance, potentially exposed to job stress and consequently to an increase in CVD risk. We explored the relationship between work-related stress and cardiovascular risk in 568 healthy workers of a flight logistic support company using the Health and Safety Executive questionnaire, the Framingham Heart Study General Cardiovascular Disease (CVD) Risk Prediction Score, and the WHO general well-being index (WHO-5). We used univariate and multivariate statistical methods to take account of possible confounders. Our results show that a low job support significantly increases the CVD risk score and decreases the WHO well-being index with reference to subjects reporting high support on the job. In addition, the well-being index of workers with high strain jobs appears lower in respect to workers employed in low strain job. The multivariate analysis confirms a protective effect of job support, and shows a detrimental influence on CVD risk by physical inactivity, regular intake of alcohol, and a low educational level. In addition, job control, job support, low strain, and high demand coupled with high control (active job) showed a beneficial effect on psychological well-being. Our results suggest that a combination of general risk factors and organizational factors contributes to increase CVD risk and well-being, representing a crucial target for intervention strategies to promote health in the workplace.

During formation of spores by Bacillus subtilis the RNA polymerase factor G ordinarily becomes active during spore formation exclusively in the prespore upon completion of engulfment of the prespore by the mother cell. Formation and activation of G ordinarily requires prior activity of F in the prespore and E in the mother cell. Here we report that in spoIIA mutants lacking both F and the anti-sigma factor SpoIIAB and in which E is not active, G nevertheless becomes active. Further, its activity is largely confined to the mother cell. Thus, there is a switch in the location of G activity from prespore to mother cell. Factors contributing to the mother cell location are inferred to be read-through of spoIIIG, the structural gene for G , from the upstream spoIIG locus and the absence of SpoIIAB, which can act in the mother cell as an anti-sigma factor to G . When the spoIIIG locus was moved away from spoIIG to the distal amyE locus, G became active earlier in sporulation in spoIIA deletion mutants, and the sporulation septum was not formed, suggesting that premature G activation can block septum formation. We report a previously unrecognized control in which SpoIIGA can prevent the appearance of G activity, and pro-E (but not E ) can counteract this effect of SpoIIGA. We find that in strains lacking F and SpoIIAB and engineered to produce active E in the mother cell without the need for SpoIIGA, G also becomes active in the mother cell.Central to cell differentiation is the establishment of distinct programs of gene expression in the different cell types involved. These programs determine the subsequent path of differentiation. Among prokaryotes, formation of spores by Bacillus subtilis has become a paradigm for the analysis of cell differentiation. Soon after the start of spore formation, bacteria divide asymmetrically to give the smaller prespore (also called the forespore) and the larger mother cell. The prespore is then engulfed by the mother cell. The prespore develops into the mature spore, whereas the mother cell ultimately lyses. The process of spore formation is characterized by the cell-specific activation of four RNA polymerase factors. Immediately after the completion of the spore division septum,

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