Éditeur(s) : HAL CCSD Cold Spring Harbor Laboratory Press
Résumé : “Human and Environmental Genomics” platform (Rennes) for Illumina sequencing / Proteomics Core Facility of the Cambridge Institute (Cancer Research UK)
International audience
Epigenetic mechanisms are believed to play key roles in the establishment of cell-specific transcription programs. Accordingly, the modified bases 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) have been observed in DNA of genomic regulatory regions such as enhancers, and oxidation of 5mC into 5hmC by Ten-eleven translocation (TET) proteins correlates with enhancer activation. However, the functional relationship between cytosine modifications and the chromatin architecture of enhancers remains elusive. To gain insights into their function, 5mC and 5hmC levels were perturbed by inhibiting DNA methyltransferases and TETs during differentiation of mouse embryonal carcinoma cells into neural progenitors, and chromatin characteristics of enhancers bound by the pioneer transcription factors FOXA1, MEIS1, and PBX1 were interrogated. In a large fraction of the tested enhancers, inhibition of DNA methylation was associated with a significant increase in monomethylation of H3K4, a characteristic mark of enhancer priming. In addition, at some specific enhancers, 5mC oxidation by TETs facilitated chromatin opening, a process that may stabilize MEIS1 binding to these genomic regions.
ISSN: 1088-9051

Droits : http://creativecommons.org/licenses/by-nc/
hal-01533248
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01533248
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01533248/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01533248/file/Genome%20Res.-2017-Mah%C3%A9-947-58.pdf
DOI : 10.1101/gr.211466.116

Éditeur(s) : HAL CCSD
Résumé : International audience
In this paper we present a microfluidic architecture dedicated to the study of Red Blood Cells (RBCs) deformability in microchannel smaller than the cell shape (biconcave disc of 7-8 μm in diameter) and cell capability to pass through slits separated by a gap value down to 2 μm, acting as a filter. This device is use in the context of RBCs disorders affecting their deformability, which is analysed versus number of cells trapped in the filter. This device can be seen as mimicking the human spleen. Microfabrication of the chip is based on polydimethylsiloxane (PDMS) associated to a two level thick photoresist mould (SU8). One level is used for microfluidic access with a 25 μm thickness towards the studied zone. The second level concerns the mimicking zones where RBCs flow through 5 μm down to 2 μm-wide slits acting like a mechanical filter. This level has a thickness of 5 μm. Devices have been tested on RBCs having specific disorder on their mechanical elasticity in order to validate the design principle. Two cases are presented in this paper: a.) Sickle RBCs inducing cell rigidity at two levels b.) Parasitized RBCs by Plasmodium falciparum. On both cases, we clearly show that deformability of RBCs influences the capability to pass through small slits (down to 2um) and thus is in relation with the pathology stage. This spleen-like microfluidic chip mimicking the RBCs filtering function is a promising tool for the exploration of RBC disorders combined with mechanical alterations.
4th European Conference on Microfluidics
Limerick, Ireland

hal-01113061
https://hal.archives-ouvertes.fr/hal-01113061

Éditeur(s) : HAL CCSD
Résumé : International audience
The Chromosome-Centric Human Proteome Project (C-HPP) aims to identify "missing" proteins in the neXtProt knowledgebase. We present an in-depth proteomics analysis of the human sperm proteome to identify testis-enriched missing proteins. Using protein extraction procedures and LC-MS/MS analysis, we detected 235 proteins (PE2-PE4) for which no previous evidence of protein expression was annotated. Through LC-MS/MS and LC-PRM analysis, data mining, and immunohistochemistry, we confirmed the expression of 206 missing proteins (PE2-PE4) in line with current HPP guidelines (version 2.0). Parallel reaction monitoring acquisition and sythetic heavy labeled peptides targeted 36 ≪one-hit wonder≫ candidates selected based on prior peptide spectrum match assessment. 24 were validated with additional predicted and specifically targeted peptides. Evidence was found for 16 more missing proteins using immunohistochemistry on human testis sections. The expression pattern for some of these proteins was specific to the testis, and they could possibly be valuable markers with fertility assessment applications. Strong evidence was also found of four "uncertain" proteins (PE5); their status should be re-examined. We show how using a range of sample preparation techniques combined with MS-based analysis, expert knowledge, and complementary antibody-based techniques can produce data of interest to the community. All MS/MS data are available via ProteomeXchange under identifier PXD003947. In addition to contributing to the C-HPP, we hope these data will stimulate continued exploration of the sperm proteome. © 2016 American Chemical Society.
Journal of Proteome Research

hal-01406074
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01406074
DOI : 10.1021/acs.jproteome.6b00400
PUBMED : 27444420

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Vertebrate genomes contain around 20,000 protein-encoding genes, of which a large fraction is still not associated with specific functions. A major task in future genomics will thus be to assign physiological roles to all open reading frames revealed by genome sequencing. Here we show that C2orf62, a highly conserved protein with little homology to characterized proteins, is strongly expressed in testis in zebrafish and mammals, and in various types of ciliated cells during zebrafish development. By yeast two hybrid and GST pull-down, C2orf62 was shown to interact with TTC17, another uncharacterized protein. Depletion of either C2orf62 or TTC17 in human ciliated cells interferes with actin polymerization and reduces the number of primary cilia without changing their length. Zebrafish embryos injected with morpholinos against C2orf62 or TTC17, or with mRNA coding for the C2orf62 C-terminal part containing a RII dimerization/docking (R2D2) - like domain show morphological defects consistent with imperfect ciliogenesis. We provide here the first evidence for a C2orf62-TTC17 axis that would regulate actin polymerization and ciliogenesis.
ISSN: 1932-6203

hal-00955242
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00955242
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00955242/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00955242/file/C2orf62_and_TTC17-accepted.pdf
DOI : 10.1371/journal.pone.0086476

Éditeur(s) : HAL CCSD Springer International Publishing
Résumé : International audience
Understanding the formation processes of maritime archaeological sites and the maritime landscape in the French West Indies is a new challenge in underwater archaeology. This chapter presents an analysis of formation and conservation processes of maritime archaeological sites in Guadeloupe using evidence from both historical and archaeological research. Formation parameters include contemporary events associated with maritime loss and the in situ geophysical regime. Questions considered include: what natural and/or anthropogenic parameters best classify maritime sites in the context of the French West Indies landscape? And: how do these parameters vary by site location? Field-tested case studies are used to assess the archaeological potential for submerged shipwreck sites for three locational typologies within the landscape: submerged, coastal, and micro-island. Geomorphic parameters, including erosion, sea level evolution, and tectonic activity, are evaluated with regard to the formation of coastal Amerindian and colonial sites. The location of shipwrecks are primarily determined by historic patterns in commercial trade and by topographical constraints associated with accessibility, risk, and the presence of natural harbors, parameters important in the Caribbean. A unique feature of Guadeloupe is the high variability of the structure of the coastline through time. The recent discovery of numerous underwater prehistoric artifacts confirms that several islands, coastal areas, and their archaeological sites have been completely submerged or eroded since their formation. The characterization of these formation processes provides both academically interesting and practical information valuable in assessing the impact of development and urbanization in Guadeloupe’s maritime landscape.
Formation Processes of Maritime Archaeological Landscapes

hal-01448703
https://hal.archives-ouvertes.fr/hal-01448703

Éditeur(s) : HAL CCSD
Résumé : International audience
In French Guiana, located on the northeastern coast of South America, bats of different species are very numerous. The infection of bats and their ticks with zoonotic bacteria, especially Rickettsia species, is so far unknown. In order to improve knowledge of these zoonotic pathogens in this French overseas department, the presence and diversity of tick-borne bacteria was investigated with molecular tools in bat ticks. In the beginning of 2013, 32 bats were caught in Saint-Jean-du-Maroni, an area close to the coast of French Guiana, and the ticks of these animals were collected. A total of 354 larvae of Argasidae soft ticks (Ornithodoros hasei) from 12 bats (Noctilio albiventris) were collected and 107 of them were analysed. DNA was extracted from the samples and quantitative real-time PCR was carried out to detect Rickettsia spp., Bartonella spp., Borrelia spp. and Coxiella burnetii. All tested samples were negative for Bartonella spp., Borrelia spp. and Coxiella burnetii. Rickettsia DNA was detected in 31 (28.9%) ticks. An almost entire (1118 base pairs long) sequence of the gltA gene was obtained after the amplification of some positive samples on conventional PCR and sequencing. A Bayesian tree was constructed using concatenated rrs, gltA, ompA, ompB, and gene D sequences. The study of characteristic sequences shows that this Rickettsia species is very close (98.3-99.8%) genetically to R. peacockii. Nevertheless, the comparative analysis of sequences obtained from gltA, ompA, ompB, rrs and gene D fragments demonstrated that this Rickettsia is different from the other members of the spotted fever group. The sequences of this new species were deposited in GenBank as Candidatus Rickettsia wissemanii. This is the first report showing the presence of nucleic acid of Rickettsia in Ornithodoros hasei ticks from South American bats. (C) 2016 Elsevier GmbH. All rights reserved.
TICKS AND TICK-BORNE DISEASES

hal-01459758
https://hal.archives-ouvertes.fr/hal-01459758
DOI : 10.1016/j.ttbdis.2016.09.004

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BackgroundMalaria is endemic in French Guiana, an overseas territory of France on the Guiana Shield. Since 2005, notified malaria cases are decreasing. However, new data show that malaria affects many Brazilian gold miners working illegally in French Guiana, the majority of whom are not counted in official data. In addition, one major concern is the usual practice of improper self-treatment in this mining population, raising fear of the development of antimalarial resistance. This prospective study, conducted in 2015, aimed to estimate the prevalence of Plasmodium spp. in illegal gold miners working in French Guiana. MethodsThe recruitment of gold miners was carried out in resting sites along the French Guiana-Suriname border, where they go for supplies, medical care or leisure. After recording agreement, three malaria diagnostic methods were performed: rapid diagnostic test, microscopy and PCR,ResultsAmong 421 persons recruited in the study, malaria prevalence, detected by nested-PCR, was 22.3% (CI=[18.3-26.3], n=94/421) of which 84% were asymptomatic. ConclusionThis significant malaria reservoir in a mobile and illegal population with difficult access to a health care system raises the threat of artemisinin resistance and puts the population of the Guiana Shield at risk of new transmission foci while countries of the region aim at malaria elimination. Even though French legislation may hamper dealing with this population, France must face the reality of malaria in illegal gold miners in order to meet its commitment to malaria elimination.
ISSN: 1475-2875

hal-01346800
https://hal.archives-ouvertes.fr/hal-01346800
https://hal.archives-ouvertes.fr/hal-01346800/document
https://hal.archives-ouvertes.fr/hal-01346800/file/2016%2C%20Douine%20-%20Prevalence%20of%20Plasmodium%20spp.%20in%20illegal%20gold%20miners%20in%20French%20Guiana%20in%202015.pdf
DOI : 10.1186/s12936-016-1367-6

Éditeur(s) : HAL CCSD WB Saunders
Résumé : International audience
Objective: the effect of physical activity on food intake regulation may be moderated by environmental temperature. The aim of the study was to determine the single and combined effects of metabolic activity and temperature on energy intake and its hormonal regulation. Methods: A randomized crossover study was conducted in the laboratory. Ten healthy and physically active young Afro-Caribbean men participated in four experimental sessions (rest at 22°C and 31°C and cycling at 60% of their maximal oxygen uptake at 22°C and 31°C, all for 40 minutes). This test period was followed by a 30-minute recovery period and then an ad libitum meal. The main outcome measures were energy balance, subjective appetite, and plasma pancreatic polypeptide (PP), cholecystokinin (CCK) and ghrelin concentrations. Results: Relative energy intake was significantly decreased whereas plasma PP was increased in the exercise conditions (p=0.004 and p=0.002, respectively). Postprandial levels of CCK were elevated only in the rest conditions. Exposure to heat induced a decrease in plasma ghrelin (p=0.031). Conclusions: Exercise induced a short-term energy deficit. However, modifications in the hormonal regulation of food intake in response to short-term heat or heat and exercise exposure seem to be minor and did not induce changes in energy intake. This trial was registered at clinicaltrials.gov as NCT02157233.
ISSN: 0026-0495

hal-01496661
https://hal.archives-ouvertes.fr/hal-01496661
https://hal.archives-ouvertes.fr/hal-01496661/document
https://hal.archives-ouvertes.fr/hal-01496661/file/Faure%20et%20al%20june%202016.pdf
DOI : 10.1016/j.metabol.2016.07.004

Éditeur(s) : HAL CCSD American Society for Investigative Pathology (ASIP)
Résumé : International audience
Semen represents the main vector of HIV dissemination worldwide, yet the origin of HIV in semen remains unclear. Viral populations distinct from those found in blood have been observed in semen, indicating local viral replication within the male genital tract. The seminal vesicles, the secretions of which constitute more than 60% of the seminal fluid, could represent a major source of virus in semen. This study is the first to investigate the susceptibility of human seminal vesicles to HIV infection both in vitro and in vivo. We developed and characterized an organotypic culture of human seminal vesicles to test for target cells and HIV infection, and, in parallel, analyzed the seminal vesicle tissues from HIV-infected donors. In vitro, in contrast to HIV-1 X4, HIV-1 R5 exposure induced productive infection. Infected cells consisted primarily of resident CD163(+) macrophages, often located close to the lumen. In vivo, HIV protein and RNA were also detected primarily in seminal vesicle macrophages in seven of nine HIV-infected donors, some of whom were receiving prolonged suppressive highly active antiretroviral therapy. These results demonstrate that human seminal vesicles support HIV infection in vitro and in vivo and, therefore, have the potential to contribute virus to semen. The presence of infected cells in the seminal vesicles of treated men with undetectable viremia suggests that this organ could constitute a reservoir for HIV.
American Journal of Pathology

inserm-00626549
http://www.hal.inserm.fr/inserm-00626549
DOI : 10.1016/j.ajpath.2011.08.005
PUBMED : 21925468

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
UNLABELLED: ABSTRACT: BACKGROUND: High circulating parasite load is one of the WHO criteria for severe falciparum malaria. During a period of 11 years (2000-2010), the frequency of hyperparasitaemia (HP) (≥4% infected erythrocytes) during bouts of malaria due to Plasmodium falciparum, Plasmodium vivax and Plasmodium malariae in patients referred to Cayenne General Hospital (CGH) in French Guiana and the frequency of their admission to the Intensive Care Unit (ICU) were evaluated. METHODS: A mean of 1,150 malaria cases were referred to the Parasitology Laboratory of CGH each year over the last decade. During this period, malaria diagnostic (microscopy) and parasitaemia evaluation have remained unchanged: determination of the parasitized erythrocytes percentage with asexual forms on thin blood smears for all cases of parasitaemia exceeding 0.1%. Patients admitted to the ICU can be counted by origin of the request for malaria testing. All the data collected retrospectively were anonymized in a standardized case report form and in database. RESULTS: Between 2000 and 2010, 12,254 bouts of malaria were confirmed at the Parasitology Laboratory of CHG: P. vivax: 56.2%, P. falciparum: 39.5%, co-infection with both species: 3.4%, P. malariae: 0.9%. HP was observed in 262 cases, at a frequency of 4.9% for P. falciparum and only 0.041% for P. vivax, with no recorded cases for P. malariae. The need for intensive care was correlated with P. falciparum parasite load: 12.3% of cases for parasitaemia of 4-9%, 21.2% for parasitaemia 10-19%, 50% for parasitaemia 20-29% and 77.8% for parasitaemia ≥30% (n=9). The patient with the highest parasitaemia (75% infected erythrocytes with asexual form) presented a major concomitant lupus flare-up treated with corticoids. He survived without obvious sequelae. CONCLUSIONS: In French Guiana during bouts of malaria, HP was observed at a frequency of ~ 5% for P. falciparum and two orders of magnitude less frequent for P. vivax. HP is a severity criterion for falciparum malaria in this endemic area. However, two of the patients with HP ≥30% were not admitted to the ICU and sequel-free cure in malaria patients with 75% parasitaemia is, therefore, possible.
ISSN: 1475-2875

inserm-00780740
http://www.hal.inserm.fr/inserm-00780740
http://www.hal.inserm.fr/inserm-00780740/document
http://www.hal.inserm.fr/inserm-00780740/file/1475-2875-12-20.pdf
DOI : 10.1186/1475-2875-12-20

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Millimeter Waves (MMW) will be used in the next-generation of high-speed wireless technologies, especially in future Ultra-Broadband small cells in 5G cellular networks. Therefore, their biocompatibilities must be evaluated prior to their massive deployment. Using a microarray- based approach, we analyzed modifications to the whole genome of a human keratinocyte model that was exposed at 60.4 GHz-MMW at an incident power density (IPD) of 20 mW/cm2 for 3 hours in athermic conditions. No keratinocyte transcriptome modifications were observed. We tested the effects of MMWs on cell metabolism by co-treating MMW-exposed cells with a glycolysis inhibitor, 2-deoxyglucose (2dG, 20 mM for 3 hours), and whole genome expression was evaluated along with the ATP content.We found that the 2dG treatment decreased the cellular ATP content and induced a high modification in the transcriptome (632 coding genes). The affected genes were associated with transcriptional repression, cellular communication and endoplasmic reticulum homeostasis. The MMW/ 2dG co-treatment did not alter the keratinocyte ATP content, but it did slightly alter the transcriptome, which reflected the capacity of MMWto interfere with the bioenergetic stress response. The RT-PCR-based validation confirmed 6 MMW-sensitive genes (SOCS3, SPRY2, TRIB1, FAM46A, CSRNP1 and PPP1R15A) during the 2dG treatment. These 6 genes encoded transcription factors or inhibitors of cytokine pathways, which raised questions regarding the potential impact of long-term or chronic MMW exposure on metabolically stressed cells. © 2016 Soubere Mahamoud et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
ISSN: 1932-6203

hal-01367149
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01367149
DOI : 10.1371/journal.pone.0160810
PUBMED : 27529420

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Objectives: The purpose of the present study was to examine the mediational role of self-confidence and anxiety in the relationship between self-esteem and claimed self-handicapping in an achievement context. Design: To test this mediational role, the three-step procedure advocated by Baron and Kenny (1986) was used. Method: After hearing and reading about specific conditions of performing that were intended to favor invoking excuses for future poor performance, 68 competitive basketball players completed measures of self-esteem, anxiety (cognitive and somatic), self-confidence, and claimed self-handicapping. Then, they warmed-up and carried out a basketball task. Results: Self-esteem negatively predicted cognitive anxiety and positively predicted self-confidence. In turn, self-confidence negatively predicted claimed self-handicapping and mediated the relationship between self-esteem and claimed self-handicapping. Cognitive and somatic anxieties did not mediate the relationship between self-esteem and claimed self-handicapping. Together, these results suggest that individuals with low self-esteem use more claimed self-handicaps because they have lower self-confidence. Conclusion: These findings shed light on the psychological processes that lead people with low self-esteem to use strategies of claimed self-handicaps.
ISSN: 1469-0292

Droits : info:eu-repo/semantics/OpenAccess
hal-01343259
https://hal.univ-antilles.fr/hal-01343259
https://hal.univ-antilles.fr/hal-01343259/document
https://hal.univ-antilles.fr/hal-01343259/file/PSE%20Manuscript%2014.03.2011-HAL.pdf
DOI : 10.1016/j.psychsport.2011.05.008

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : International audience
Four lyophilizated liver flüke antigens and one of hydatid fluid were examined for the presence of blood group like antigens P1, A, B, M and N by an hemagglutination inhibition test with hyperimmune and natural hemagglutinating sera. P1 or P1-like substance was found in the extracts of "Fasciola hepatica" and "F. gigantica" in a lower concentration than in echinoccocal fluid. This presence may explain the occurrence of anti-P1 antibodies in patients infected with liver flüke and belonging to the P2 blood group. However biochemical studies will be necessary to determine if the P1 activity is due to the blood group P1 substance of the red cell itself or due to a P1 like substance.
ISSN: 0369-8114

hal-00715431
https://hal.univ-antilles.fr/hal-00715431
PUBMED : 392420

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Plasma membrane is an early target of polycyclic aromatic hydrocarbons (PAH). We previously showed that the PAH prototype, benzo[a]pyrene (B[a]P), triggers apoptosis via DNA damage-induced p53 activation (genotoxic pathway) and via remodeling of the membrane cholesterol-rich microdomains called lipid rafts, leading to changes in pH homeostasis (non-genotoxic pathway). As omega-3 (n-3) fatty acids can affect membrane composition and function or hamper in vivo PAH genotoxicity, we hypothesized that addition of physiologically relevant levels of polyunsaturated n-3 fatty acids (PUFAs) might interfere with B[a]P-induced toxicity. The effects of two major PUFAs, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), were tested on B[a]P cytotoxicity in the liver epithelial cell line F258. Both PUFAs reduced B[a]P-induced apoptosis. Surprisingly, pre-treatment with DHA increased the formation of reactive B[a]P metabolites, resulting in higher levels of B[a]P-DNA adducts. EPA had no apparent effect on B[a]P metabolism or related DNA damage. EPA and DHA prevented B[a]P-induced apoptotic alkalinization by affecting Na(+)/H(+) exchanger 1 activity. Thus, the inhibitory effects of omega-3 fatty acids on B[a]P-induced apoptosis involve a non-genotoxic pathway associated with plasma membrane remodeling. Our results suggest that dietary omega-3 fatty acids may have marked effects on the biological consequences of PAH exposure.
ISSN: 0009-2797

hal-00950341
https://hal.archives-ouvertes.fr/hal-00950341
https://hal.archives-ouvertes.fr/hal-00950341/document
https://hal.archives-ouvertes.fr/hal-00950341/file/DENDELE_et_al_2013-unmarked.pdf
PUBMED : 24246761

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
BACKGROUND:Sickle cell anaemia (SCA) is a severe hereditary haemoglobinopathy characterised by haemorheological abnormalities, which play a role in the occurrence of several acute and chronic clinical complications. While βS -haplotypes and alpha-thalassaemia modulate SCA clinical severity, their effects on blood rheology have been incompletely described. The aim of this study was to test the effects of these genetic modifiers on the haemorheological properties and clinical complication of children with SCA.PROCEDURE:Steady-state haemorheological profile, biological parameters, βS -haplotypes, alpha-globin status, vaso-occlusive crisis (VOC) and acute chest syndrome frequencies were analysed in 128 children (aged 5 to 18 years) with SCA.RESULTS:Patients with alpha-thalassaemia showed increased red blood cell (RBC) deformability and aggregation compared to those without. Median VOC rate was higher in patients with homozygous alpha-thalassaemia compared to those with a normal alpha genotype. Conversely, the haemorheological profile and clinical complications were not influenced by the βS -haplotypes in our study.CONCLUSION:Our results demonstrate that alpha-thalassaemia is associated with higher risk for VOC events in children with SCA, which may be due in part to its effects on RBC deformability and aggregation.
ISSN: 1545-5009

hal-01668317
https://hal.univ-antilles.fr/hal-01668317
DOI : 10.1002/pbc.26455
PUBMED : 28097791

Éditeur(s) : HAL CCSD John Libbey Eurotext
Résumé : International audience
Prostate cancer is the most frequent cancer affecting men in most Western countries. Certain risk factors have been identified (age, family history, ethnic origin), but the aetiology of this cancer remains largely unknown. However, a role for environmental factors is strongly suspected. Questions have been raised concerning the role of the chemical substances generated by human activities in the occurrence of this disease. Diverse studies have consistently demonstrated a higher risk of prostate cancer in agricultural populations than in the general population. The hypothesis that this higher risk is linked to the use of pesticides has been tested in a number of studies, mostly in North America and Europe. However, to date, with a few possible exceptions, it has been impossible to demonstrate a significant association between exposure to pesticides or a chemical family of pesticides and prostate cancer. In the face of these uncertainties, rigorous studies are required, with objective measurements of exposure, taking into account confounding factors and individual risk factors, making it possible to assess gene-environment interactions.
ISSN: 0007-4551

inserm-00504733
http://www.hal.inserm.fr/inserm-00504733
DOI : 10.1684/bdc.2008.0812
PUBMED : 19258224

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Vascular resistance and tissue perfusion may be both affected by impaired vascular function and increased blood viscosity. Little is known about the effects of vascular function on the occurrence of painful vaso-occlusive crises (VOC) in children with sickle cell anemia (SCA). The aim of the present study was to determine which side of the balance (blood viscosity or vascular function) is the most deleterious in SCA and increases the risk for frequent hospitalized VOC. Microvascular function, microcirculatory oxygenation and blood viscosity were determined in a group of 22 SCA children/adolescents at steady state and a group of 13 healthy children/adolescents. Univariate analyses demonstrated blunted microvascular reactivity during local thermal heating test and decreased microcirculatory oxygenation in SCA children compared to controls. Multivariate analysis revealed that increased blood viscosity and decreased microcirculatory oxygenation were independent risk factors of frequent VOC in SCA. In contrast, the level of microvascular dysfunction does not predict VOC rate. In conclusion, increased blood viscosity is usually well supported in healthy individuals where vascular function is not impaired. However, in the context of SCA, microvascular function is impaired and any increase of blood viscosity or decrease in microcirculatory oxygenation would increase the risks for frequent VOC.
ISSN: 1079-9796

hal-01668335
https://hal.univ-antilles.fr/hal-01668335
DOI : 10.1016/j.bcmd.2015.10.005

Éditeur(s) : HAL CCSD Frontiers
Résumé : International audience
The generation of handwriting is a complex neuromotor skill requiring the interaction of many cognitive processes. It aims at producing a message to be imprinted as an ink trace left on a writing medium. The generated trajectory of the pen tip is made up of strokes superimposed over time. The Kinematic Theory of rapid human movements and its family of lognormal models provide analytical representations of these strokes, often considered as the basic unit of handwriting. This paradigm has not only been experimentally confirmed in numerous predictive and physiologically significant tests but it has also been shown to be the ideal mathematical description for the impulse response of a neuromuscular system. This latter demonstration suggests that the lognormality of the velocity patterns can be interpreted as reflecting the behavior of subjects who are in perfect control of their movements. To illustrate this interpretation, we present a short overview of the main concepts behind the Kinematic Theory and briefly describe how its models can be exploited, using various software tools, to investigate these ideal lognormal behaviors. We emphasize that the parameters extracted during various tasks can be used to analyze some underlying processes associated with their realization. To investigate the operational convergence hypothesis, we report on two original studies. First, we focus on the early steps of the motor learning process as seen as a converging behavior toward the production of more precise lognormal patterns as young children practicing handwriting start to become more fluent writers. Second, we illustrate how aging affects handwriting by pointing out the increasing departure from the ideal lognormal behavior as the control of the fine motricity begins to decline. Overall, the paper highlights this developmental process of merging toward a lognormal behavior with learning, mastering this behavior to succeed in performing a given task, and then gradually deviating from it with aging.
ISSN: 1664-1078

hal-01098124
https://hal.archives-ouvertes.fr/hal-01098124
DOI : 10.3389/fpsyg.2013.0094

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
The etiology of congenital heart defect (CHD) combines environmental and genetic factors. So far, there were studies reporting on the screening of a single gene on unselected CHD or on familial cases selected for specific CHD types. Our goal was to systematically screen a proband of familial cases of CHD on a set of genetic tests to evaluate the prevalence of disease-causing variant identification. A systematic screening of GATA4, NKX2-5, ZIC3 and Multiplex ligation-dependent probe amplification (MLPA) P311 Kit was setup on the proband of 154 families with at least two cases of non-syndromic CHD. Additionally, ELN screening was performed on families with supravalvular arterial stenosis. Twenty-two variants were found, but segregation analysis confirmed unambiguously the causality of 16 variants: GATA4 (1 x), NKX2-5 (6 x), ZIC3 (3 x), MLPA (2 x) and ELN (4 x). Therefore, this approach was able to identify the causal variant in 10.4% of familial CHD cases. This study demonstrated the existence of a de novo variant even in familial CHD cases and the impact of CHD variants on adult cardiac condition even in the absence of CHD. This study showed that the systematic screening of genetic factors is useful in familial CHD cases with up to 10.4% elucidated cases. When successful, it drastically improved genetic counseling by discovering unaffected variant carriers who are at risk of transmitting their variant and are also exposed to develop cardiac complications during adulthood thus prompting long-term cardiac follow-up. This study provides an important baseline at dawning of the next-generation sequencing era.
ISSN: 1018-4813

hal-01404211
https://hal-univ-bourgogne.archives-ouvertes.fr/hal-01404211
DOI : 10.1038/ejhg.2015.105
PUBMED : 26014430

Éditeur(s) : HAL CCSD
Résumé : International audience
Earthquake, volcanic eruption, cyclone, flood, tsunami, the Caribbean are particularly vulnerable to many natural hazards. Citizen Education to hazard mitigation is much more important in French West Indies than in Paris. With national, curriculum, evaluation and textbooks, how science education in French West Indies manage the challenge to take account this particularity of our territories? Based on this example and others, the aim of this communication is to present a science education theoretical background focus on contexts studies. During science teaching, learning effects due to different context like social, cultural or language could be described as contextual effects. But others micro-didactic effects of contexts could also be identified as linked with specificity of natural environment. These effects manifest a strain between a goal of teaching or learning and its implementation, when this stain is due in the educational process in different contexts involved.To ensure the quality of education, reference and quantify the effects of educational context seems to be necessary. it should be interested in the process leading to the emergence of these contexts. We propose a simplified model of these processes initially described as meetings of mechanisms operating within a network of transposition of designs. Then we question these processes by degree or forms of contextualization (low to high) and crossed these two approaches, giving an initial typology of contextualisation process. It then emerges the idea that these processes are constrained by resistances. We retain the following three: epistemological, social and educational. As these constraints are expressed in different ways according to disciplines, the data suggest the existence of disciplinary contextualization profiles. All these three approaches (network implementation, degree of contextualization, disciplinary profiles) are three tools for analyzing contextual phenomena which remain to test the robustness and operational character for the training analysis context.
Biennial Conference of Caribbean Academy of Sciences
Barbados, Barbados

hal-01539482
https://hal.univ-antilles.fr/hal-01539482