Influence des conditions de travail sur la santé des employés de production

Une intervention ergonomique a été réalisée dans la maison-mère d'un grand groupe suisse constructeur d'équipements. Les situations de travail qui ont été étudiées sont des ateliers de tôleries, de mécanique et de soudure. La demande d'intervention à l'IST (Institut universitaire romand de santé au travail) est partie du constat par la hiérarchie et par l'infirmière du travail qu'un nombre croissant d'employés de production souffraient de maux de dos et de stress et qu'il était nécessaire d'entreprendre des améliorations du travail afin de réduire ces symptômes. [Auteurs]

In Bacillus subtilis W23, the duet sigmaXsigmaM, two sigma factors of the extracytoplasmic function subfamily, are required for septum and wall synthesis under batch culture conditions.

The synthesis of poly(RboP), the main Bacillus subtilis W23 teichoic acid, is encoded by tarDF-tarABIJKL operons, the latter being controlled by two promoters designated PtarA-int and PtarA-ext. Analysis by lacZ fusions reveals that PtarA-int activity exhibits sharp increases at the beginning and end of the transition between exponential and stationary growth phase. As confirmed by mRNA quantification, these increases are mediated by ECF sigma factors sigmaX and sigmaM respectively. In liquid media, strain W23 sigX sigM double mutants experience serious difficulties in the transition and stationary growth phases. Inactivation of sigmaX- and sigmaM-controlled regulons, which precludes transcription from PtarA-int, leads to (i) delays in chromosome segregation and septation and (ii) a transient loss of up to 30% of the culture OD or lysis. However, specific inactivation of PtarA-int, leading mainly to a shortage of poly(RboP), does not affect growth while, nevertheless, interfering with normal septation, as revealed by electron microscopy. The different sigM transcription in strains W23 and 168 is discussed. In W23, expression of tarA and sigM, which is shown to control divIC, is inversely correlated with growth rate, suggesting that the sigM regulon is involved in the control of cell division.

Response of the Pacific oyster Crassostrea gigas, Thunberg 1793, to pesticide exposure under experimental conditions.

Pesticide run-off into the ocean represents a potential threat to marine organisms, especially bivalves living in coastal environments. However, little is known about the effects of environmentally relevant concentrations of pesticides at the individual level. In this study, the suppression subtractive hybridisation technique was used to discover the main physiological function affected by a cocktail of three pesticides (lindane, metolachlor and carbofuran) in the Pacific oyster Crassostrea gigas. Two oyster populations exposed to different pollution levels in the wild were investigated. The pesticide concentrations used to induce stress were close to those found in the wild. In a time course experiment, the expression of three genes implicated in iron metabolism and oxidative stress as well as that of two ubiquitous stress proteins was examined. No clear regulation of gene or protein expression was found, potentially due to a low-dose effect. However, we detected a strong site- and organ-specific response to the pesticides. This study thus (1) provides insight into bivalve responses to pesticide pollution at the level of the transcriptome, which is the first level of response for organisms facing pollution, and (2) raises interesting questions concerning the importance of the sites and organs studied in the toxicogenomic field.

Identification of small RNAs in Pseudomonas species

Summary: Bacterial small RNAs (sRNAs) are transcripts most of which have regulatory functions. Sequence and secondary structure elements enable numerous sRNAs to interact with mRNAs or with regulatory proteins resulting in diverse regulatory effects on virulence, iron storage, organization of cell envelope proteins or stress response. sRNAs having high affinity for RsmA-like RNA-binding proteins are important for posttranscriptional regulation in various Gram-negative bacteria. In Pseudomonas spp., the GacS/GacA two component system positively controls the production of such sRNAs. They titrate RsmA-like proteins and thus overcome translational repression due to these proteins. As a consequence, secondary metabolites can be produced that are implicated in the biocontrol capacity of P. fluorescens or in the virulence of P. aeruginosa. A genome-wide search carried out in P. aeruginosa PAO1 and in closely related Pseudomonas spp. resulted in the identification of 15 genes coding for sRNAs. Eight of these are novel, the remaining seven have previously been observed. Among them, the 1698 sRNA gene was expressed under GacA control, whereas the transcription of 1887 sRNA gene was transcribed under the control of the anaerobic regulator Anr in an oxygen-limited environment. Overexpression of 1698 sRNA in P. fluorescens strain CHAO did not affect the expression of the GacA-regulated hcnA gene (first gene of the operon coding for HCN synthase), indicating that 1698 sRNA is probably not part of the secondary metabolite regulation pathway. The expression of 1698 sRNA was positively regulated by RpoS in both P. aeruginosa PAO 1 and P. ,fluorescens CHAO and appeared to be modulated temporarily by oxidative stress conditions. However, the effect of 1698 sRNA on oxidative stress survival has not yet been established. Hfq protein interacted with 1698 sRNA in vitro and improved 1698 sRNA expression in vivo in P. aeruginosa. In P. fluorescens, GacA and Hfq were both required for expression of rpoS and GacA showed a positively control on the hfq expression; therefore, at least in this organism, GacA control of 1698 sRNA expression may act indirectly via Hfq and RpoS. Different methods were employed to find abase-pairing target for 1698 sRNA. In a proteomic analysis carried out in P. aeruginosa, positive regulation by 1698 sRNA was observed for Soda, the iron-associated superoxide dismutase, an enzyme involved in oxidative stress resistance. A sequence complementary with 1698 sRNA was predicted to be located in the 5' leader of soda mRNA. However, base-pairing between soda mRNA and 1698 sRNA remains to be proven. In conclusion, this work has revealed eight novel sRNAs and novel functions of two sRNAs in Pseudomonas spp. Résumé Les petits ARNs non-codants (sRNAs) produits par les bactéries sont des transcrits ayant pour la plupart des activités régulatrices importantes. Leurs séquences nucléotidiques ainsi que leurs structures secondaires permettent aux sRNAs d'interagir soit avec des RNA messagers (mRNAs), de sorte à modifier l'expression des protéines pour lesquelles ils codent, soit avec des protéines régulatrices liant des rnRNAs, ce qui a pour effet de modifier l'expression de ces mRNAs. Des sRNAs sont impliqués dans diverses voies de régulation, telles que celles qui régissent la virulence, le stockage du fer, l'organisation des protéines de l'enveloppe bactérienne ou la réponse au stress. Chez les Pseudomonas spp., le système à deux composantes GacS/GacA contrôle la production de métabolites secondaires. Ceux-ci sont engagés dans l'établissement du biocontrôle, chez P. fluorescens, ou. de la virulence, chez P. aeruginosa. La régulation génique dirigée par le système GacS/GacA fait intervenir les sRNAs du type RsmZ, capables de contrecarrer l'action au niveau traductionnel exercée par les protéines régulatrices du type RsmA. Une recherche au niveau du génome a été menée chez P. aeruginosa PAO1 de même que chez des espèces qui lui sont étroitement apparentées, débouchant sur la mise en évidence de 15 gènes codant pour des sRNAs. Parmi ceux-ci, huit ont été découverts pour la première fois et sept confirment des travaux publiés. L'expression du gène du sRNAs 1698 s'avère être régulée par GacA, vraisemblablement de manière indirecte. La transcription du gène du sRNA 1887 montre une dépendance envers Anr, régulateur de l'anaérobiose, et envers une carence en oxygène. La surexpression du sRNA 1698 chez P. fluorescens CHAO n'affecte pas l'expression de hcnA, un gène du régulon GacA, laissant supposer que le sRNA n'intervient pas dans la régulation des métabolites secondaires. Chez P. aeruginosa PAOI et chez P. fluorescens CHAO, RpoS, le facteur sigma du stress, est nécessaire à l'expression du sRNA 1698, et la concentration de ce dernier est modulée par des conditions de stress oxydatif. Toutefois, un effet du sRNA 1698 quant à la survie suite au stress oxydatif n'a pas été établi. Par ailleurs, l'interaction entre le sRNA 1698 et Hfq, la protéine chaperone de RNAs, in vitro ainsi qu'un rôle positif de Hfq pour l'expression du sRNA 1698 in vivo ont été démontrés chez P. aeruginosa. L'induction de l'expression par GacA de rpoS et de hfq a été confirmée chez P. fluorescens CHAO, suggérant que la régulation par GacA du sRNA 1698 pourrait se faire par l'intermédiaire de RpoS et Hfq. Diverses méthodes ont été employées pour identifier un transcrit qui puisse être apparié par le sRNA 1698. Une analyse de protéome chez P. aeruginosa montre que l'expression de Soda, la superoxyde dismutase associée au fer, est positivement régulée par le sRNA 1698. Soda est une enzyme impliquée dans la résistance au stress oxydatif. Une séquence de complémentarité avec le sRNA 1698 a bien été prédite sur le leader 5' du mRNA de soda. Cependant, l'appariement entre le sRNA et son transcrit cible est encore à prouver. En conclusion, ce travail a dévoilé huit nouveaux sRNAs et de nouvelles fonctions pour deux sRNAs chez les Pseudomonas.

Promoting Corporate Responsibility in Private Banking: Necessary and Sufficient Conditions for Joining the Wolfsberg Initiative Against Money Laundering

In recent years, the fight against money laundering has emerged as a key issue of financial regulation. The Wolfsberg Group is an important multistakeholder agreement establishing corporate responsibility (CR) principles against money laundering in a domain where international coordination remains otherwise difficult. The fact that 10 out of the 25 top private banking institutions joined this initiative opens up an interesting puzzle concerning the conditions for the participation of key industry players in the Wolfsberg Group. The article presents a fuzzy-set analysis of seven hypotheses based on firm-level organizational factors, the macro-institutional context, and the regulatory framework. Results from the analysis of these 25 financial institutions show that public ownership of the bank and the existence of a code of conduct are necessary conditions for participation in the Wolfsberg Group, whereas factors related to the type of financial institution, combined with the existence of a black list, are sufficient for explaining participation.

The kidney during hibernation and arousal from hibernation. A natural model of organ preservation during cold ischaemia and reperfusion.

BACKGROUND: During hibernation the kidney is in a hypothermic condition where renal blood flow is minimal and urine production is much reduced. Periodical arousal from hibernation is associated with kidney reperfusion at increasing body temperature, and restored urine production rate. METHODS: To assess the degree of structural preservation during such extreme conditions, the kidney cortex was investigated by means of electron microscopy in the dormouse Muscardinus avellanarius during winter hibernation, arousal from hibernation and the summer active period. RESULTS: Results show that the fine structure of the kidney cortex is well preserved during hibernation. In the renal corpuscle, a sign of slight lesion was the focal presence of oedematous endothelial cells and/or podocytes. Proximal convoluted tubule cells showed fully preserved ultrastructure and polarity, and hypertrophic apical endocytic apparatus. Structural changes were associated with increased plasma electrolytes, creatinine and urea nitrogen, and proteinuria. During the process of arousal the fine structure of the kidney cortex was also well maintained. CONCLUSION: These results demonstrate that dormice are able to fully preserve kidney cortex structure under extreme conditions resembling e.g. severe ischaemia or hypothermic organ storage for transplantation, and reperfusion. Elucidation of the mechanisms involved in such a natural model of organ preservation could be relevant to human medicine.

Calbindin-immunoreactive sensory neurons in dissociated dorsal root ganglion cell cultures of chick embryo: role of culture conditions.

Immunoreactivity to calbindin D-28k, a vitamin D-dependent calcium-binding protein, is expressed by neuronal subpopulations of dorsal root ganglia (DRG) in the chick embryo. To determine whether the expression of this phenotypic characteristic is maintained in vitro and controlled by environmental factors, dissociated DRG cell cultures were performed under various conditions. Subpopulations of DRG cells cultured at embryonic day 10 displayed calbindin-immunoreactive cell bodies and neurites in both neuron-enriched or mixed DRG cell cultures. The number of calbindin-immunoreactive ganglion cells increased up to 7-10 days of culture independently of the changes occurring in the whole neuronal population. The presence of non-neuronal cells, which promotes the maturation of the sensory neurons, tended to reduce the percentage of calbindin-immunoreactive cell bodies. Addition of horse serum enhanced both the number of calbindin-positive neurons and the intensity of the immunostaining, but does not prevent the decline of the subpopulation of calbindin-immunoreactive neurons during the second week of culture; on the contrary, the addition of muscular extract to cultures at 10 days maintained the number of calbindin-expressing neurons. While calbindin-immunoreactive cell bodies grown in culture were small- or medium-sized, no correlation was found between cell size and immunostaining density. At the ultrastructural level, the calbindin immunoreaction was distributed throughout the neuroplasm. These results indicate that the expression of calbindin by sensory neurons grown in vitro may be modulated by horse serum-contained factors or interaction with non-neuronal cells. As distinct from horse serum, muscular extract is able to maintain the expression of calbindin by a subpopulation of DRG cells.

Effect of a national primary care pay for performance scheme on emergency hospital admissions for ambulatory care sensitive conditions: controlled longitudinal study.

OBJECTIVE: To estimate the impact of a national primary care pay for performance scheme, the Quality and Outcomes Framework in England, on emergency hospital admissions for ambulatory care sensitive conditions (ACSCs). DESIGN: Controlled longitudinal study. SETTING: English National Health Service between 1998/99 and 2010/11. PARTICIPANTS: Populations registered with each of 6975 family practices in England. MAIN OUTCOME MEASURES: Year specific differences between trend adjusted emergency hospital admission rates for incentivised ACSCs before and after the introduction of the Quality and Outcomes Framework scheme and two comparators: non-incentivised ACSCs and non-ACSCs. RESULTS: Incentivised ACSC admissions showed a relative reduction of 2.7% (95% confidence interval 1.6% to 3.8%) in the first year of the Quality and Outcomes Framework compared with ACSCs that were not incentivised. This increased to a relative reduction of 8.0% (6.9% to 9.1%) in 2010/11. Compared with conditions that are not regarded as being influenced by the quality of ambulatory care (non-ACSCs), incentivised ACSCs also showed a relative reduction in rates of emergency admissions of 2.8% (2.0% to 3.6%) in the first year increasing to 10.9% (10.1% to 11.7%) by 2010/11. CONCLUSIONS: The introduction of a major national pay for performance scheme for primary care in England was associated with a decrease in emergency admissions for incentivised conditions compared with conditions that were not incentivised. Contemporaneous health service changes seem unlikely to have caused the sharp change in the trajectory of incentivised ACSC admissions immediately after the introduction of the Quality and Outcomes Framework. The decrease seems larger than would be expected from the changes in the process measures that were incentivised, suggesting that the pay for performance scheme may have had impacts on quality of care beyond the directly incentivised activities.

Energy cost of glucose storage in human subjects during glucose-insulin infusions.

The effect of graded levels of hyperinsulinemia on energy expenditure, while euglycemia was maintained by glucose infusion, was examined in 22 healthy young male volunteers by using the euglycemic insulin clamp technique in combination with indirect calorimetry. Insulin was infused at five rates to achieve steady-state hyperinsulinemic plateaus of 62 +/- 4, 103 +/- 5, 170 +/- 10, 423 +/- 16, and 1,132 +/- 47 microU/ml. Total body glucose uptake during each of the five insulin clamp studies was 0.41, 0.50, 0.66, 0.74, and 0.77 g/min, respectively. Glucose storage (calculated from the difference between total body glucose uptake minus total glucose oxidation) was 0.25, 0.29, 0.43, 0.49, and 0.52 g/min for each group, respectively, and represented over 60-70% of total glucose uptake. The net increment in energy expenditure after intravenous glucose was 0.08, 0.10, 0.14, 0.17, and 0.23 kcal/min, respectively. Throughout the physiological and supraphysiological range of insulinemia, there was a significant relationship (r = 0.95, P less than 0.001) between the increment in energy expenditure and glucose storage, indicating an energy cost of 0.45 kcal/g glucose stored. However, at each level of hyperinsulinemia, the theoretical value for the energy cost of glucose storage (assuming that all of the glucose is stored in the form of glycogen) could account for only 45-63% of the actual increase in energy expenditure that was measured by indirect calorimetry. These results indicate that factors in addition to glucose storage as glycogen must be responsible for the increase in energy expenditure that accompanies glucose infusion.