The ‘servicelization’ of societies: towards new paradigms in work organization

This article proposes an alternative to the theoretical framework for the approaches to phenomena of the servicelization of work in complex organizational contexts. In contradiction to the models which question the industrialization processes, theoretical paradigms are presented which highlight integration in the analyses of new concepts of work, such as co-production, the supremacy of the client/user, the evaluation of organizational performances and competence logic. Finally, a model of the service enterprise is presented with its alternative configurations in a proposal for empirical application, some of which is now being carried out in Portugal

Transcriptome response to pollutants and insecticides in the dengue vector Aedes aegypti using next-generation sequencing technology

<p>Abstract</p> <p>Background</p> <p>The control of mosquitoes transmitting infectious diseases relies mainly on the use of chemical insecticides. However, mosquito control programs are now threatened by the emergence of insecticide resistance. Hitherto, most research efforts have been focused on elucidating the molecular basis of inherited resistance. Less attention has been paid to the short-term response of mosquitoes to insecticides and pollutants which could have a significant impact on insecticide efficacy. Here, a combination of LongSAGE and Solexa sequencing was used to perform a deep transcriptome analysis of larvae of the dengue vector <it>Aedes aegypti </it>exposed for 48 h to sub-lethal doses of three chemical insecticides and three anthropogenic pollutants.</p> <p>Results</p> <p>Thirty millions 20 bp cDNA tags were sequenced, mapped to the mosquito genome and clustered, representing 6850 known genes and 4868 additional clusters not located within predicted genes. Mosquitoes exposed to insecticides or anthropogenic pollutants showed considerable modifications of their transcriptome. Genes encoding cuticular proteins, transporters, and enzymes involved in the mitochondrial respiratory chain and detoxification processes were particularly affected. Genes and molecular mechanisms potentially involved in xenobiotic response and insecticide tolerance were identified.</p> <p>Conclusions</p> <p>The method used in the present study appears as a powerful approach for investigating fine transcriptome variations in genome-sequenced organisms and can provide useful informations for the detection of novel transcripts. At the biological level, despite low concentrations and no apparent phenotypic effects, the significant impact of these xenobiotics on mosquito transcriptomes raise important questions about the 'hidden impact' of anthropogenic pollutants on ecosystems and consequences on vector control.</p

Effects of Aging and Caloric Restriction on Fiber Type Composition, Mitochondrial Morphology and Dynamics in Rat Oxidative and Glycolytic Muscles

Aging is associated with a progressive decline in muscle mass and strength, a process known as sarcopenia. Evidence indicates that mitochondrial dysfunction plays a causal role in sarcopenia and suggests that alterations in mitochondrial dynamics/morphology may represent an underlying mechanism. Caloric restriction (CR) is among the most efficient nonpharmacological interventions to attenuate sarcopenia in rodents and is thought to exert its beneficial effects by improving mitochondrial function. However, CR effects on mitochondrial morphology and dynamics, especially in aging muscle, remain unknown. To address this issue, we investigated mitochondrial morphology and dynamics in the oxidative soleus (SOL) and glycolytic white gastrocnemius (WG) muscles of adult (9-month-old) ad libitum-fed (AL; A-AL), old (22-month-old) AL-fed (O-AL), and old CR (O-CR) rats. We show that CR attenuates the aging-related decline in the muscle-to-body-weight ratio, a sarcopenic index. CR also prevented the effects of aging on muscle fiber type composition in both muscles. With aging, the SOL displayed fragmented SubSarcolemmal (SS) and InterMyoFibrillar (IMF) mitochondria, an effect attenuated by CR. Aged WG displayed enlarged SS and more complex/branched IMF mitochondria. CR had marginal anti-aging effects on WG mitochondrial morphology. In the SOL, DRP1 (pro-fission protein) content was higher in O-AL vs YA-AL, and Mfn2 (pro-fusion) content was higher in O-CR vs A-AL. In the gastrocnemius, Mfn2, Drp1, and Fis1 (pro-fission) contents were higher in O-AL vs A-AL. CR reduced this aging-related increase in Mfn2 and Fis1 content. Overall, these results reveal for the first time that aging differentially impacts mitochondrial morphology and dynamics in different muscle fiber types, by increasing fission/fragmentation in oxidative fibers while enhancing mitochondrial size and branching in glycolytic fibers. Our results also indicate that although CR partially attenuates aging-related changes in mitochondrial dynamics in glycolytic fibers, its anti-aging effect on mitochondrial morphology is restricted to oxidative fibers

Parvovirus 4 in French in-patients: a study of haemodialysis and lung transplant cohorts

International audienceThe epidemiology and the clinical implication of human parvovirus 4 (PARV4) in human populations is still under evaluation. The distribution of PARV4 DNA was determined in cohorts of French haemodialysis and lung transplant patients. Plasma samples (n=289) were tested for PARV4 by real-time PCR assay (ORF2), and amplification products selected at random were sequenced. Analysis of available serological and biological markers was also undertaken. Fifty-seven samples out of 185 (30.8%) were positive for PARV4 DNA in the cohort of haemodialysis patients. A higher prevalence of the virus was identified in individuals with markers of HBV infection. PARV4 was also identified in 14 out of 104 samples (13.5%) from lung transplant recipients, with no clear-cut association with available clinical markers. Point mutations located on the zone of real-time detection were identified for some amplification products. This study describes the detection of PARV4 in the blood of haemodialysis and lung transplanted patients with significant difference in prevalence in these two cohorts. Further studies will be needed in order to understand better both the potential implication in host health and the natural history of this virus

Exploring the molecular basis of insecticide resistance in the dengue vector Aedes aegypti: a case study in Martinique Island (French West Indies)

<p>Abstract</p> <p>Background</p> <p>The yellow fever mosquito <it>Aedes aegypti </it>is a major vector of dengue and hemorrhagic fevers, causing up to 100 million dengue infections every year. As there is still no medicine and efficient vaccine available, vector control largely based on insecticide treatments remains the only method to reduce dengue virus transmission. Unfortunately, vector control programs are facing operational challenges with mosquitoes becoming resistant to commonly used insecticides. Resistance of <it>Ae. aegypti </it>to chemical insecticides has been reported worldwide and the underlying molecular mechanisms, including the identification of enzymes involved in insecticide detoxification are not completely understood.</p> <p>Results</p> <p>The present paper investigates the molecular basis of insecticide resistance in a population of <it>Ae. aegypti </it>collected in Martinique (French West Indies). Bioassays with insecticides on adults and larvae revealed high levels of resistance to organophosphate and pyrethroid insecticides. Molecular screening for common insecticide target-site mutations showed a high frequency (71%) of the sodium channel 'knock down resistance' (<it>kdr</it>) mutation. Exposing mosquitoes to detoxification enzymes inhibitors prior to bioassays induced a significant increased susceptibility of mosquitoes to insecticides, revealing the presence of metabolic-based resistance mechanisms. This trend was biochemically confirmed by significant elevated activities of cytochrome P450 monooxygenases, glutathione S-transferases and carboxylesterases at both larval and adult stages. Utilization of the microarray <it>Aedes Detox Chip </it>containing probes for all members of detoxification and other insecticide resistance-related enzymes revealed the significant constitutive over-transcription of multiple detoxification genes at both larval and adult stages. The over-transcription of detoxification genes in the resistant strain was confirmed by using real-time quantitative RT-PCR.</p> <p>Conclusion</p> <p>These results suggest that the high level of insecticide resistance found in <it>Ae. aegypti </it>mosquitoes from Martinique island is the consequence of both target-site and metabolic based resistance mechanisms. Insecticide resistance levels and associated mechanisms are discussed in relation with the environmental context of Martinique Island. These finding have important implications for dengue vector control in Martinique and emphasizes the need to develop new tools and strategies for maintaining an effective control of <it>Aedes </it>mosquito populations worldwide.</p