Historicisme absolu et histoire des religions: L'oeuvre de Dario Sabbatucci

Dans ce livre sur les rapports de la foi, de la religion et de la culture, l'auteur - dont Flammarion avait publié un magistral Essai sur le mysticisme grec - et spécialiste de la religion de la Rome antique, très critique envers la phénoménologie religieuse, (Rudolf Otto, Van der Leeuw, Eliade), passe tour à tour en revue « la profession de foi » et les Confessions chrétiennes, la christologie au Concile de Florence, la notion d'« ordre cosmique » dans le domaine indo-iranien, la querelle médiévale des Investitures, le thème du « mandat céleste » en Chine, etc. Toutes les productions magico-religieuses sont ici interprétées comme autant de formations historiques dont il s'agit de retracer les processus d'apparition et de développement ainsi que la fonction culturelle spécifique dans un contexte donné. Mais sont également mis en perspective les pratiques, discours, représentations propres aux savoirs qui étudient ces productions. Une vision des faits religieux qui montre que l'histoire des religions « a problématisé les objets de foi, mais non la foi elle-même », l'abandonnant à la psychologie, à la philosophie ou à l'anthropologie. Or la foi a une histoire, étroitement liée à celle de l'Occident : elle n'est pas, selon l'auteur, une qualité innée chez l'homme, mais relève de circonstances culturelles, non exportables hors de l'Occident. Un essai profondément stimulant...

Response characteristics of arsenic-sensitive bioreporters expressing the gfp reporter gene

This paper describes the development of an analytical technique for arsenic analyses that is based on genetically-modified bioreporter bacteria bearing a gene encoding for the production of a green fluorescent protein (gfp). Upon exposure to arsenic (in the aqueous form of arsenite), the bioreporter production of the fluorescent reporter molecule is monitored spectroscopically. We compared the response measured as a function of time and concentration by steady-state fluorimetry (SSF) to that measured by epi-fluorescent microscopy (EFM). SSF is a bulk technique; as such it inherently yields less information, whereas EFM monitors the response of many individual cells simultaneously and data can be processed in terms of population averages or subpopulations. For the bioreporter strain used here, as well as for the literature we cite, the two techniques exhibit similar performance characteristics. The results presented here show that the EFM technique can compete with SSF and shows substantially more promise for future improvement; it is a matter of research interest to develop optimized methods of EFM image analysis and statistical data treatment. EFM is a conduit for understanding the dynamics of individual cell response vs. population response, which is not only a matter of research interest, but is also promising in the practical terms of developing micro-scale analysis.

Hyaline fibromatosis syndrome inducing mutations in the ectodomain of anthrax toxin receptor 2 can be rescued by proteasome inhibitors.

Hyaline Fibromatosis Syndrome (HFS) is a human genetic disease caused by mutations in the anthrax toxin receptor 2 (or cmg2) gene, which encodes a membrane protein thought to be involved in the homeostasis of the extracellular matrix. Little is known about the structure and function of the protein or the genotype-phenotype relationship of the disease. Through the analysis of four patients, we identify three novel mutants and determine their effects at the cellular level. Altogether, we show that missense mutations that map to the extracellular von Willebrand domain or the here characterized Ig-like domain of CMG2 lead to folding defects and thereby to retention of the mutated protein in the endoplasmic reticulum (ER). Mutations in the Ig-like domain prevent proper disulphide bond formation and are more efficiently targeted to ER-associated degradation. Finally, we show that mutant CMG2 can be rescued in fibroblasts of some patients by treatment with proteasome inhibitors and that CMG2 is then properly transported to the plasma membrane and signalling competent, identifying the ER folding and degradation pathway components as promising drug targets for HFS.

MP2RAGE, a self bias-field corrected sequence for improved segmentation and T-1-mapping at high field

The large spatial inhomogeneity in transmit B, field (B-1(+)) observable in human MR images at hi h static magnetic fields (B-0) severely impairs image quality. To overcome this effect in brain T-1-weighted images the, MPRAGE sequence was modified to generate two different images at different inversion times MP2RAGE By combining the two images in a novel fashion, it was possible to create T-1-weigthed images where the result image was free of proton density contrast, T-2* contrast, reception bias field, and, to first order transmit field inhomogeneity. MP2RAGE sequence parameters were optimized using Bloch equations to maximize contrast-to-noise ratio per unit of time between brain tissues and minimize the effect of B-1(+) variations through space. Images of high anatomical quality and excellent brain tissue differentiation suitable for applications such as segmentation and voxel-based morphometry were obtained at 3 and 7 T. From such T-1-weighted images, acquired within 12 min, high-resolution 3D T-1 maps were routinely calculated at 7 T with sub-millimeter voxel resolution (0.65-0.85 mm isotropic). T-1 maps were validated in phantom experiments. In humans, the T, values obtained at 7 T were 1.15 +/- 0.06 s for white matter (WM) and 1.92 +/- 0.16 s for grey matter (GM), in good agreement with literature values obtained at lower spatial resolution. At 3 T, where whole-brain acquisitions with 1 mm isotropic voxels were acquired in 8 min the T-1 values obtained (0.81 +/- 0.03 S for WM and 1.35 +/- 0.05 for GM) were once again found to be in very good agreement with values in the literature. (C) 2009 Elsevier Inc. All rights reserved.

Lack of association between connexin40 polymorphisms and coronary artery disease.

OBJECTIVE: Cx40 is a gap junction protein important for cell-cell communication in the endothelium. Polymorphisms in the promoter region of the human Cx40 gene, -44G>A and +71A>G, were shown to reduce Cx40 transcription by half. As mice with an endothelial-specific deletion of Cx40 are more susceptible to atherosclerosis, this study was designed to discover a correlation between these polymorphisms and atherosclerosis in European populations.¦METHODS AND RESULTS: 803 patients referred to the Geneva University Hospitals for elective coronary angiography were divided according to the number of significantly stenosed vessels (from 0 to 3) and were genotyped for the Cx40 polymorphisms. Genotype distribution in the control group was -44GG/+71AA=59.8%, -44AG/+71AG=35.1% and -44AA/+71GG=5.2%. Surprisingly, this distribution was similar in the CAD group, with -44GG/+71AA=58.5%, -44AG/+71AG=37.6% and -44AA/+71GG=3.8% (p=0.67). Moreover, no significant association between histological carotid plaque composition of culprit lesions and Cx40 polymorphisms could be detected in 583 Dutch patients of the Athero-Express study.¦CONCLUSIONS: Despite a clear antiatherogenic role of Cx40 in mice, our study could not detect an association of Cx40 promoter polymorphisms and CAD in human. Moreover, a correlation with atherosclerotic plaque stability or hypertension could not be demonstrated either. Connexin polymorphisms affecting channel function may be of greater importance for cardiovascular disease than polymorphisms affecting the expression level of the protein.

Digit somatotopy in the human cerebellum: a 7T fMRI study.

The representation of the human body in the human cerebellum is still relatively unknown, compared to the well-studied homunculus in the primary somatosensory cortex. The investigation of the body representation in the cerebellum and its somatotopic organisation is complicated because of the relatively small dimensions of the cerebellum, compared to the cerebrum. Somatotopically organised whole-body homunculi have previously been reported in both humans and rats. However, whether individual digits are represented in the cerebellum in a somatotopically organised way is much less clear. In this study, the high spatial resolution and high sensitivity to the blood oxygenation level dependent (BOLD) signal of 7T fMRI were employed to study the BOLD responses in the human cerebellum to the stroking of the skin of individual digits, the hand and forearm. For the first time, a coarse somatotopic organisation of the digits, ordered from D1-D5, could be visualised in individual human subjects in both the anterior (lobule V) and the posterior (lobule VIII) lobes of the cerebellum using a somatosensory stimulus. The somatotopic gradient in lobule V was found consistently in the posterior to anterior direction, with the thumb most posterior, while the direction of the somatotopic gradient in lobule VIII differed between subjects. No somatotopic organisation was found in Crus I. A comparison of the digit patches with the hand patch revealed that the digit regions are completely covered by the hand region in both the anterior and posterior lobes of the cerebellum, in a non-somatotopic manner. These results demonstrate the promise of ultra-high field, high-resolution fMRI for studies of the cerebellum.

Genetic analysis of phenoxyalkanoic acid degradation in Sphingomonas herbicidovorans MH.

Phenoxyalkanoic acid degradation is well studied in Beta- and Gammaproteobacteria, but the genetic background has not been elucidated so far in Alphaproteobacteria. We report the isolation of several genes involved in dichlor- and mecoprop degradation from the alphaproteobacterium Sphingomonas herbicidovorans MH and propose that the degradation proceeds analogously to that previously reported for 2,4-dichlorophenoxyacetic acid (2,4-D). Two genes for alpha-ketoglutarate-dependent dioxygenases, sdpA(MH) and rdpA(MH), were found, both of which were adjacent to sequences with potential insertion elements. Furthermore, a gene for a dichlorophenol hydroxylase (tfdB), a putative regulatory gene (cadR), two genes for dichlorocatechol 1,2-dioxygenases (dccA(I/II)), two for dienelactone hydrolases (dccD(I/II)), part of a gene for maleylacetate reductase (dccE), and one gene for a potential phenoxyalkanoic acid permease were isolated. In contrast to other 2,4-D degraders, the sdp, rdp, and dcc genes were scattered over the genome and their expression was not tightly regulated. No coherent pattern was derived on the possible origin of the sdp, rdp, and dcc pathway genes. rdpA(MH) was 99% identical to rdpA(MC1), an (R)-dichlorprop/alpha-ketoglutarate dioxygenase from Delftia acidovorans MC1, which is evidence for a recent gene exchange between Alpha- and Betaproteobacteria. Conversely, DccA(I) and DccA(II) did not group within the known chlorocatechol 1,2-dioxygenases, but formed a separate branch in clustering analysis. This suggests a different reservoir and reduced transfer for the genes of the modified ortho-cleavage pathway in Alphaproteobacteria compared with the ones in Beta- and Gammaproteobacteria.

Biocontrol by phenazine-1-carboxamide-producing Pseudomonas chlororaphis PCL1391of tomato root rot caused by Fusarium oxysporum f. sp. radicis-lycopersici

Seventy bacterial isolates from the rhizosphere of tomato were screened for antagonistic activity against the tomato foot and root rot-causing fungal pathogen Fusarium oxysporum f. sp. radicis-lycopersici. One isolate, strain PCL1391, appeared to be an efficient colonizer of tomato roots and an excellent biocontrol strain in an F. oxysporum/tomato test system. Strain PCL1391 was identified as Pseudomonas chlororaphis and further characterization showed that it produces a broad spectrum of antifungal factors (AFFs), including a hydrophobic compound, hydrogen cyanide, chitinase(s), and protease(s). Through mass spectrometry and nuclear magnetic resonance, the hydrophobic compound was identified as phenazine-1-carboxamide (PCN). We have studied the production and action of this AFF both in vitro and in vivo. Using a PCL1391 transposon mutant, with a lux reporter gene inserted in the phenazine biosynthetic operon (phz), we showed that this phenazine biosynthetic mutant was substantially decreased in both in vitro antifungal activity and biocontrol activity. Moreover, with the same mutant it was shown that the phz biosynthetic operon is expressed in the tomato rhizosphere. Comparison of the biocontrol activity of the PCN-producing strain PCL1391 with those of phenazine-1-carboxylic acid (PCA)-producing strains P. fluorescens 2-79 and P. aureofaciens 30-84 showed that the PCN-producing strain is able to suppress disease in the tomato/F. oxysporum system, whereas the PCA-producing strains are not. Comparison of in vitro antifungal activity of PCN and PCA showed that the antifungal activity of PCN was at least 10 times higher at neutral pH, suggesting that this may contribute to the superior biocontrol performance of strain PCL1391 in the tomato/F. oxysporum system.

Genome-wide meta-analysis of common variant differences between men and women.

The male-to-female sex ratio at birth is constant across world populations with an average of 1.06 (106 male to 100 female live births) for populations of European descent. The sex ratio is considered to be affected by numerous biological and environmental factors and to have a heritable component. The aim of this study was to investigate the presence of common allele modest effects at autosomal and chromosome X variants that could explain the observed sex ratio at birth. We conducted a large-scale genome-wide association scan (GWAS) meta-analysis across 51 studies, comprising overall 114 863 individuals (61 094 women and 53 769 men) of European ancestry and 2 623 828 common (minor allele frequency >0.05) single-nucleotide polymorphisms (SNPs). Allele frequencies were compared between men and women for directly-typed and imputed variants within each study. Forward-time simulations for unlinked, neutral, autosomal, common loci were performed under the demographic model for European populations with a fixed sex ratio and a random mating scheme to assess the probability of detecting significant allele frequency differences. We do not detect any genome-wide significant (P < 5 × 10(-8)) common SNP differences between men and women in this well-powered meta-analysis. The simulated data provided results entirely consistent with these findings. This large-scale investigation across ~115 000 individuals shows no detectable contribution from common genetic variants to the observed skew in the sex ratio. The absence of sex-specific differences is useful in guiding genetic association study design, for example when using mixed controls for sex-biased traits.

Disagreements among cohabiting and married couples in 22 European countries

Background: Cross-national research suggests that married people have higher levels of well-being than cohabiting people. However, relationship quality has both positive and negative dimensions. Researchers have paid little attention to disagreements within cohabiting and married couples. Objective: This study aims to improve our understanding of the meaning of cohabitation by examining disagreements within marital and cohabiting relationships. We examine variations in couples' disagreements about housework, paid work and money by country and gender. Methods: The data come from the 2004 European Social Survey. We selected respondents living in a heterosexual couple relationship and aged between 18 and 45. In total, the study makes use of data from 22 European countries and 9,657 people. Given that our dependent variable was dichotomous, we estimated multilevel logit models, with (1) disagree and (0) never disagree. Results: We find that cohabitors had more disagreements about housework, the same disagreements about money, but fewer disagreements about paid work than did married people. These findings could not be explained by socio-economic or demographic measures, nor did we find gender or cross-country differences in the association between union status and conflict. Conclusions: Cohabiting couples have more disagreements about housework but fewer disagreements about paid work than married people. There are no gender or cross-country differences in these associations. The results provide further evidence that the meaning of cohabitation differs from that of marriage, and that this difference remains consistent across nations.

Life history analysis of integrative and conjugative element activation in growing microcolonies of Pseudomonas.

Integrative and conjugative elements (ICE) are in some ways parasitic mobile DNA that propagate vertically through replication with the bacterial host chromosome but at low frequencies can excise and invade new recipient cells through conjugation and reintegration (horizontal propagation). The factors that contribute to successful horizontal propagation are not very well understood. Here, we study the influence of host cell life history on the initiation of transfer of a model ICE named ICEclc in bacteria of the genus Pseudomonas. We use time-lapse microscopy of growing and stationary-phase microcolonies of ICEclc bearing cells in combination with physiological staining and gene reporter analysis in stationary-phase suspended cells. We provide evidence that cell age and cell lineage are unlikely to play a role in the decision to initiate the ICEclc transfer program. In contrast, cells activating ICEclc show more often increased levels of reactive oxygen species and membrane damage than nonactivating cells, suggesting that some form of biochemical damage may make cells more prone to ICEclc induction. Finally, we find that ICEclc active cells appear spatially at random in a microcolony, which may have been a selective advantage for maximizing ICEclc horizontal transmission to new recipient species.