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We commend Resnik and Master (2011) not only for bringing ethical problems to light in conceptual bioethics research but also for attempting to elaborate practical criteria for authorship. The stat...

International audience

Shogaols, the major constituents of thermally processed ginger, have been proven to be highly effective anticancer agents. Our group has identified cysteine-conjugated shogaols (M2, M2', and M2″) as the major metabolites of [6]-, [8]-, and [10]-shogaol in human and found that M2 is a carrier of its parent molecule [6]-shogaol in cancer cells and in mice, while being less toxic to normal colon fibroblast cells. The objectives of this study are to determine whether M2' and M2″ behave in a similar manner to M2, in both metabolism and efficacy as anticancer agents, and to further explore the biological pro-apoptotic mechanisms of the cysteine-conjugated shogaols against human colon cancer cells HCT-116 and HT-29. Our results show that [8]- and [10]-shogaol have similar metabolic profiles to [6]-shogaol and exhibit similar toxicity toward human colon cancer cells. M2' and M2″ both show low toxicity against normal colon cells but retain potency against colon cancer cells, suggesting that they have similar activity to M2. We further demonstrate that the cysteine-conjugated shogaols can cause cancer cell death through the activation of the mitochondrial apoptotic pathway. Our results show that oxidative stress activates a p53 pathway that ultimately leads to p53 up-regulated modulator of apoptosis (PUMA) induction and down-regulation of B-cell lymphoma 2 (Bcl-2), followed by cytochrome c release, perturbation of inhibitory interactions of X-linked inhibitor of apoptosis protein (XIAP) with caspases, and finally caspase 9 and 3 activation and cleavage. A brief screen of the markers attenuated by the proapoptotic activity of M2 revealed similar results for [8]- and [10]-shogaol and their respective cysteine-conjugated metabolites M2' and M2″. This study highlights the cysteine-conjugated metabolites of shogaols as novel dietary colon cancer preventive agents.

International audience; Context. In Λ-CDM models, galaxies are thought to grow both through continuous cold gas accretion coming from the cosmic web and episodic merger events. The relative importance of these different mechanisms at different cosmic epochs is nevertheless not yet understood well.Aims. We aim to address questions related to galaxy mass assembly through major and minor wet merging processes in the redshift range 1

Uptake and depuration kinetics of dissolved [14C]C12-6-linear alkylbenzene sulfonate (LAS) were determined in the shrimp Palaemonetes varians using environmentally relevant exposure concentration. The shrimp concentrated LAS from seawater with a mean BCF value of 120 L kg-1 after a 7-day exposure. Uptake biokinetics were best described by a saturation model, with an estimated BCFss, of 159 ± 34 L kg-1, reached after 11.5 days. Shrimp weight influenced significantly BCF value with smaller individuals presenting higher affinity to LAS. To the light of a whole body autoradiography, major accumulation of LAS occurred in the cephalothorax circulatory system (gills, heart, hepatopancreas) and ocular peduncle, but not in the flesh, limiting potential transfer to human consumers. LAS depuration rate constant value of the shrimp was 1.18 ± 0.08 d-1 leading to less than 1% of remaining LAS in its tissues after 8 days of depuration.

Faces aux nouveaux enjeux du développement durable, l’intensification raisonnée dessystèmes d’élevages est une voie allant vers l’augmentation de la production tout en minimisant leseffets négatifs sur l’environnement. Au pâturage, cette intensification prend la forme d’unaccroissement de la charge animale par hectare, ce qui n’est pas sans conséquences. En bovinsallaitants, la contrainte porte principalement sur l’augmentation du rendement des prairies. Lessolutions préconisées étaient l’augmentation de l’apport d’intrants (fertilisation, irrigation), et l’utilisationde fourrages à fort potentiel. Chez les petits ruminants, la principale contrainte est le parasitismegastro-intestinal. Une des solutions est l’association avec des bovins. Des systèmes contrastés visantà évaluer les performances de production de ces systèmes ont été mis en place en unitéexpérimentale. Pour les systèmes bovins allaitants, une base de données (BDD) a été construite àpartir du suivi d’un essaie conduit de 1999 à 2010 (Fanchone et al, 2012). Pour les systèmes mixtesbovins caprins, une autre BDD a été construite à partir d’un essaie conduit de 2007 à 2010 (Mahieu,2013). La promotion de tels systèmes auprès des éleveurs nécessite l’évaluation conjointe de leursperformances de production et de leurs performances environnementales. L’analyse de cycle de vie(ACV) a déjà été utilisée pour effectuer l’évaluation environnementale de tels systèmes en milieutempéré (Nguyen et al, 2012). Cependant, à notre connaissance, très peu de travaux sont disponiblesen milieu tropical. Par ailleurs, les données IPCC en milieu tropical proviennent pour la plupartd’adaptation de données mesurées en milieu tempérés. L’ACV a été appliqué à ces deux systèmes.Les analyses se sont limitées aux portes des systèmes, l’unité fonctionnelle était le kilogramme depoids vif. L’inventaire s’est basé sur les BDD ainsi que les nombreux travaux analytiques menéslocalement sur ces systèmes. Les équations locales ont été privilégiées relativement à celles issues dela bibliographie tropicale. Les données de l’IPCC ont été utilisées en dernier recours.

International @ EAU+CRL:EPU:CGU; International audience; Under the effect of physical activity human body activate the mechanism of thermoregulation by producing sweat. The incipient sweat is inherently odorless but moisture and warmth promotes the proliferation of microorganisms on the surface of the skin. In particular, sportswears and shoes are suited environments for the growth of several bacteria and fungus. These microorganisms are responsible for the degradation of the compounds present in sweat and on the skin surface, in malodorous molecules. To address this problem of odor associated with perspiration, it seems appropriate to confer to textiles a function against micro-organisms and odorant molecules. The way explored in this work is the use of photocatalysis [1] in order to inhibit the growth of bacteria and to directly destroy the malodorous compounds. During this project, various catalysts and impregnation methods of the textile with catalysts were investigated. Optimized the amount of catalyst was determined in term of adhesion and performances. Their photocatalytic activities were first evaluated in aqueous phase with their performances on the formic acid photocatalytic oxidation. Then, an experimental setup, including an electronic nose, was designed to evaluate the photocatalytic activity in gas phase. The performances of these materials have been studied under UV light on the degradation of isovaleric acid, a model smelly compound. The efficiency of these materials under UV-A lamp and LEDs centered at a wavelength of 365 nm were compared and the photonic flux optimized. Complemently, the adhesion of the catalyst is evaluated by mechanical tests such as leaching (ISO 6330) or abrasion tests (ISO 12947-2). In parallel, bacteriological tests on the strain S.epidermidis, responsible for foot malodor, was performed using the ISO 20743 standard with and without photocatalysis. The influence of the exposition time and UV-A irradiation flux were studied on the degradation of this bacteria. Photocatalytic textiles have clearly shown an ability to degrade isovaleric acid in air and formic acid in water with a rate increasing with the increase of the quantity of titania deposited on the textile. The optimal coverage of photocatalyst and degradation rate have been determined in each case. These textiles also present antimicrobial activity after a few time under UV-A light and no effect on these bacteria in darkness, that could be consider as a proof of undestroying cutaneous flora. Reference [1]S. Silver, L.T. Phung, G. Silver, Journal of Industrial Microbiology & Biotechnology, 33 (2006) 627-634.

Summary According to a growing consensus among biomedical researchers, community engagement can improve the ethics and outcomes of clinical trials. Although successful efforts to develop community engagement practices in HIV/AIDS research have been reported, little attention has been given to engagement with the community in tuberculosis research. This article aims to draw attention to some existing community engagement initiatives in tuberculosis research and to resources that might help tuberculosis researchers to establish and implement community engagement programmes for their trials. One of these resources—the good participatory practice guidelines for tuberculosis drug trials—offers a conceptual framework and practical guidance for community engagement in tuberculosis research. To build momentum and to improve community engagement, lessons need to be shared, and formal assessment strategies for community engagement initiatives need to be developed. To build successfully on the promising activities described in this personal view, research funders and sponsors should show leadership in allocation of resources for the implementation and assessment of community engagement programmes in tuberculosis trials.

The living world has evolved and is evolving through interspecific relationships between organisms. The diversity of these interactions is enormous going from mutualism to parasitism. Humans live with a multitude of microorganisms, essential for their biology. However, interactions are not always advantageous. Indeed, many organisms might become pathogens, such as the Plasmodium species, the causative agents of malaria. Like many other microorganisms, they are << Machiavellian >> in their capacity to elaborate a range of reproduction strategies, giving them a huge advantage in terms of adaptation. Here, we discuss the role played by parasites in the ecology and evolution of living organisms and particularly of humans. In the study of infectious diseases, humans are legitimately the focal point, although they represent only one ecosystem among many others and not taking this into account certainly biases our global view of the system. Indeed, we know only a minimal fraction of the microorganisms we live with. However, parasites have shaped and are still shaping the human genome. Several genetic signatures are the proofs of the selection pressures by parasites that humankind has endured during its evolution. But, ultimately, what are the solutions for living with pathogens? Should we eradicate them or should we learn how to control and manage them? (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.

Enhancing the effectiveness, efficiency, and fairness of interventions is an increasing source of concern in the field of disaster response. As a result, the expansion of the disaster relief evidence base has been identified as a pressing need. There has been a corresponding increase in discussions of ethical standards and procedures for disaster research. In general, these discussions have focused on elucidating how traditional research ethics concerns can be operationalized in disaster settings. Less attention has been given to the exploration of the ethical implications of heterogeneity within the field of disaster research. Hence, while current efforts to discuss the ethics of disaster research in low-resource settings are very encouraging, it is clear that further initiatives will be crucial to promote the ethical conduct of disaster research. In this article, we explore how the ethical review of disaster research conducted in low-resource settings should account for this diversity. More specifically, we consider how the nature of the project (what?), sociopolitical and physical environment of research sites (where?), temporal proximity to the disaster event (when?), objectives motivating the research (why?), and identity of the stakeholders involved in the research process (who?) all relate to the ethics of disaster research.

High-resolution simulations often rely on the Adaptive Mesh Resolution (AMR) technique to optimize memory consumption versus attainable precision. While this technique allows for dramatic improvements in terms of computing performance, the analysis and visualization of its data outputs remain challenging. The lack of effective volume renderers for the octree-based AMR used by the RAMSES simulation program has led to the development of the solutions presented in this paper. Two custom algorithms are discussed, based on the splatting and the ray-casting techniques. Their usage is illustrated in the context of the visualization of a high-resolution, 6000-processor simulation of a Milky Way-like galaxy. Performance obtained in terms of memory management and parallelism speedup are presented.

Our previous study found that [6]-shogaol, a major bioactive component in ginger, is extensively metabolized in cancer cells and in mice. It is unclear whether these metabolites retain bioactivity. The aim of the current study is to synthesize the major metabolites of [6]-shogaol and evaluate their inhibition of growth and induction of apoptosis in human cancer cells. Twelve metabolites of [6]-shogaol (M1, M2, and M4-M13) were successfully synthesized using simple and easily accessible chemical methods. Growth inhibition assays showed that most metabolites of [6]-shogaol had measurable activities against human cancer cells HCT-116 and H-1299. In particular, metabolite M2 greatly retained the biological activities of [6]-shogaol, with an IC(50) of 24.43 µM in HCT-116 human colon cancer cells and an IC(50) of 25.82 µM in H-1299 human lung cancer cells. Also exhibiting a relatively high potency was thiol-conjugate M13, with IC(50) values of 45.47 and 47.77 µM toward HCT-116 and H-1299 cells, respectively. The toxicity evaluation of the synthetic metabolites (M1, M2, and M4-M13) against human normal fibroblast colon cells CCD-18Co and human normal lung cells IMR-90 demonstrated a detoxifying metabolic biotransformation of [6]-shogaol. The most active metabolite M2 had almost no toxicity to CCD-18Co and IMR-90 normal cells with IC(50)s of 99.18 and 98.30 µM, respectively. TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling) assay indicated that apoptosis was triggered by metabolites M2, M13, and its two diastereomers M13-1 and M13-2. There was no significant difference between the apoptotic effect of [6]-shogaol and the effect of M2 and M13 after 6 hour treatment.

BACKGROUND: Research conducted following natural disasters such as earthquakes, floods or hurricanes is crucial for improving relief interventions. Such research, however, poses ethical, methodological and logistical challenges for researchers. Oversight of disaster research also poses challenges for research ethics committees (RECs), in part due to the rapid turnaround needed to initiate research after a disaster. Currently, there is limited knowledge available about how RECs respond to and appraise disaster research. To address this knowledge gap, we investigated the experiences of REC members who had reviewed disaster research conducted in low- or middle-income countries. METHODS: We used interpretive description methodology and conducted in-depth interviews with 15 respondents. Respondents were chairs, members, advisors, or coordinators from 13 RECs, including RECs affiliated with universities, governments, international organizations, a for-profit REC, and an ad hoc committee established during a disaster. Interviews were analyzed inductively using constant comparative techniques. RESULTS: Through this process, three elements were identified as characterizing effective and high-quality review: timeliness, responsiveness and rigorousness. To ensure timeliness, many RECs rely on adaptations of review procedures for urgent protocols. Respondents emphasized that responsive review requires awareness of and sensitivity to the particularities of disaster settings and disaster research. Rigorous review was linked with providing careful assessment of ethical considerations related to the research, as well as ensuring independence of the review process. CONCLUSION: Both the frequency of disasters and the conduct of disaster research are on the rise. Ensuring effective and high quality review of disaster research is crucial, yet challenges, including time pressures for urgent protocols, exist for achieving this goal. Adapting standard REC procedures may be necessary. However, steps should be taken to ensure that ethics review of disaster research remains diligent and thorough. Language: en

Background The presence in Morocco of Argasid ticks of the Ornithodoros erraticus complex, the vector of tick-borne relapsing fever (TBRF) in North Africa, has been known since 1919, but the disease is rarely diagnosed and few epidemiological data are available. Methodology/Principal Findings Between 2006 and 2011, we investigated the presence of Ornithodoros ticks in rodent burrows in 34 sites distributed across Morocco. We also collected small mammals in 10 sites and we investigated TBRF in febrile patients in Kenitra district. The prevalence of Borrelia infections was assessed by nested PCR amplification in ticks and the brain tissue of small mammals, and by evaluation of thick blood films in patients. A high proportion of burrows were infested with ticks of the O. erraticus complex in all regions of Morocco, with a mean of 39.5% for the whole country. Borrelia infections were found in 39/382 (10.2%) of the ticks and 12/140 (8.6%) of the rodents and insectivores studied by PCR amplification, and 102 patients tested positive by thick blood film. Five small mammalian species were found infected: Dipodillus campestris, Meriones shawi, Gerbillus hoogstrali, Gerbillus occiduus and Atelerix algirus. Three Borrelia species were identified in ticks and/or rodents: B. hispanica, B. crocidurae and B. merionesi. Conclusions/Significance Tick populations belonging to O. erraticus complex are widely distributed in Morocco and a high proportion of ticks and small mammals are infected by Borrelia species. Although rarely diagnosed, TBRF may be a common cause of morbidity in all regions of Morocco., Author Summary In North Africa, Argasid ticks of the Ornithodoros erraticus complex are the only known vector of Borrelia infections causing tick-borne relapsing fever (TBRF) in humans. There is limited data on vector distribution, the animal reservoir of the disease has never been investigated, and there is no published data on TBRF patients. Our aim was to systematically investigate the distribution of O. erraticus s.l. in most regions of Morocco, to measure the proportion of infected ticks, to identify small mammalian species that act as potential reservoir, and to analyze data on TBRF patients fortuitously collected during a malaria eradication program. Our study shows that a high proportion of rodent burrows are colonized by vector ticks in all regions of Morocco from the Atlantic Sahara to the Mediterranean coast. We identified three Borrelia species in ticks and/or small mammals: B. hispanica, B. crocidurae and B. merionesi. We report five species of small mammals found infected for the first time. Our analysis of 102 TBRF patients shows that the disease is strictly seasonal in northwestern Morocco with a maximum incidence during summer. We believe that TBRF, although rarely diagnosed, is a common cause of morbidity in all regions of Morocco.

International audience; Antimicrobial textiles (65% cotton - 35% polyester) were functionalized using a patented technology that combines an antimicrobial molecule - polyhexamethylene biguanide (PHMB) and a precipitating agent - sodium laurylsulphate. Surface characterization was performed by x-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry, and both techniques made clear signatures of PHMB at the top surface of treated textiles. Washing led to a strong decrease of PHMB concentration at the surface. Comparison of textile surface analysis and antimicrobial tests indicated that the amount of PHMB at its extreme surface of textiles after five or 10 industrial washings was sufficient to inhibit Listeria innocua but not Pseudomonas aeruginosa growth. The viability of L. innocua cells after contact with PHMB-treated textile after one industrial washing was estimated using the Live/Dead BacLight kit (Molecular Probes, Eugene, OR): the combination of epifluorescence microscopy observations coupled with classic enumeration allowed detection of the presence of viable but nonculturable cells.

Ginger has received extensive attention because of its antioxidant, anti-inflammatory, and antitumor activities. However, the metabolic fate of its major components is still unclear. In the present study, the metabolism of [6]-shogaol, one of the major active components in ginger, was examined for the first time in mice and in cancer cells. Thirteen metabolites were detected and identified, seven of which were purified from fecal samples collected from [6]-shogaol-treated mice. Their structures were elucidated as 1-(4'-hydroxy-3'-methoxyphenyl)-4-decen-3-ol (M6), 5-methoxy-1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-one (M7), 3',4'-dihydroxyphenyl-decan-3-one (M8), 1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-ol (M9), 5-methylthio-1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-one (M10), 1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-one (M11), and 5-methylthio-1-(4'-hydroxy-3'-methoxyphenyl)-decan-3-ol (M12) on the basis of detailed analysis of their (1)H, (13)C, and two-dimensional NMR data. The rest of the metabolites were identified as 5-cysteinyl-M6 (M1), 5-cysteinyl-[6]-shogaol (M2), 5-cysteinylglycinyl-M6 (M3), 5-N-acetylcysteinyl-M6 (M4), 5-N-acetylcysteinyl-[6]-shogaol (M5), and 5-glutathiol-[6]-shogaol (M13) by analysis of the MS(n) (n = 1-3) spectra and comparison to authentic standards. Among the metabolites, M1 through M5, M10, M12, and M13 were identified as the thiol conjugates of [6]-shogaol and its metabolite M6. M9 and M11 were identified as the major metabolites in four different cancer cell lines (HCT-116, HT-29, H-1299, and CL-13), and M13 was detected as a major metabolite in HCT-116 human colon cancer cells. We further showed that M9 and M11 are bioactive compounds that can inhibit cancer cell growth and induce apoptosis in human cancer cells. Our results suggest that 1) [6]-shogaol is extensively metabolized in these two models, 2) its metabolites are bioactive compounds, and 3) the mercapturic acid pathway is one of the major biotransformation pathways of [6]-shogaol.

Despite the recognition of its importance, guidance on community engagement practices for researchers remains underdeveloped, and there is little empirical evidence of what makes community engagement effective in biomedical research. We chose to study the Navrongo Health Research Centre in northern Ghana because of its well-established community engagement practices and because of the opportunity it afforded to examine community engagement in a traditional African setting. Our findings suggest that specific preexisting features of the community have greatly facilitated community engagement and that using traditional community engagement mechanisms limits the social disruption associated with research conducted by outsiders. Finally, even in seemingly ideal, small, and homogeneous communities, cultural issues exist, such as gender inequities, that may not be effectively addressed by traditional practices alone.

National audience

Until very recently, only one species (P. reichenowi) was known to be a phylogenetic sister lineage of P. falciparum, the main malignant agent of human malaria. In 2009 and 2010, new studies have revealed the existence of several new phylogenetic species related to this deadly parasite and infecting chimpanzees and gorillas in Africa. These discoveries invite us to explore a whole set of new questions, which we briefly do in this article.

Linear Alkylbenzene Sulfonates (LAS) are ubiquitous surfactants. Traces can be found in coastal environments. Sorption and toxicity of C12-LAS congeners were studied in controlled conditions (2-3500 µg C12LAs/L) in five marine phytoplanktonic species, using standardized methods. IC50 values ranged from 0.5 to 2 mg LAS/L. Sorption of 14C12-6 LAS isomer was measured at environmentally relevant trace levels (4 µg/L) using liquid scintillation counting. Steady-state sorption on algae was reached within 5 h in the order dinoflagellate > diatoms > green algae. The sorption data, fitted a L-type Freundlich isotherm, indicating saturation. Desorption was rapid but a low LAS fraction was still sorbed after 24 h. Toxic cell concentration was 0.38 +/- 0.09 mg/g for the studied species. LAS toxicity results from sorption on biological membranes leading to non-specific disturbance of algal growth. Results indicate that LAS concentrations in coastal environments do not represent a risk for these organisms.

International audience

International audience

International audience