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991.
Olivier Allard 《The journal of the Royal Anthropological Institute》2013,19(3):545-561
This article relates three contexts crucially defined by the experience of grief and distress among the Warao, an Amerindian population of Venezuela: ritual wailing performed by women at death, in front of the corpse; drunken intoxication, which essentially takes place on 2 November (the Day of the Dead), during and after visits to cemeteries; and discursive references, in the course of ordinary interactions, to the fact that one will cry, or has cried, for someone else. It shows how emotional states can be intentionally managed and yet experienced as moving forces, and stresses the ethical efficacy of sorrow, which accounts for the funerary and memorial practices of the Warao. 相似文献
992.
993.
Guojie Cao Jianghong Meng Errol Strain Robert Stones James Pettengill Shaohua Zhao Patrick McDermott Eric Brown Marc Allard 《PloS one》2013,8(2)
Salmonella Newport has ranked in the top three Salmonella serotypes associated with foodborne outbreaks from 1995 to 2011 in the United States. In the current study, we selected 26 S. Newport strains isolated from diverse sources and geographic locations and then conducted 454 shotgun pyrosequencing procedures to obtain 16–24 × coverage of high quality draft genomes for each strain. Comparative genomic analysis of 28 S. Newport strains (including 2 reference genomes) and 15 outgroup genomes identified more than 140,000 informative SNPs. A resulting phylogenetic tree consisted of four sublineages and indicated that S. Newport had a clear geographic structure. Strains from Asia were divergent from those from the Americas. Our findings demonstrated that analysis using whole genome sequencing data resulted in a more accurate picture of phylogeny compared to that using single genes or small sets of genes. We selected loci around the mutS gene of S. Newport to differentiate distinct lineages, including those between invH and mutS genes at the 3′ end of Salmonella Pathogenicity Island 1 (SPI-1), ste fimbrial operon, and Clustered, Regularly Interspaced, Short Palindromic Repeats (CRISPR) associated-proteins (cas). These genes in the outgroup genomes held high similarity with either S. Newport Lineage II or III at the same loci. S. Newport Lineages II and III have different evolutionary histories in this region and our data demonstrated genetic flow and homologous recombination events around mutS. The findings suggested that S. Newport Lineages II and III diverged early in the serotype evolution and have evolved largely independently. Moreover, we identified genes that could delineate sublineages within the phylogenetic tree and that could be used as potential biomarkers for trace-back investigations during outbreaks. Thus, whole genome sequencing data enabled us to better understand the genetic background of pathogenicity and evolutionary history of S. Newport and also provided additional markers for epidemiological response. 相似文献
994.
Aurore Palud Camille Marciniak David Montaigne Xavier Marechal Caroline Ballot Sidi Mohamed Hassoun Brigitte Decoster Remi Neviere Steve Lancel 《PloS one》2013,8(3)
Aims
Development of metabolic syndrome is associated with impaired cardiac performance, mitochondrial dysfunction and pro-inflammatory cytokine increase, such as the macrophage migration inhibitory factor MIF. Depending on conditions, MIF may exert both beneficial and deleterious effects on the myocardium. Therefore, we tested whether pharmacological inhibition of MIF prevented or worsened metabolic syndrome-induced myocardial dysfunction.Methods and Results
C57BL/6J mice were fed for ten weeks with 60% fat-enriched diet (HFD) or normal diet (ND). MIF inhibition was obtained by injecting mice twice a week with ISO-1, for three consecutive weeks. Then, triglycerides, cholesterol, fat mass, glucose intolerance, insulin resistance, ex vivo cardiac contractility, animal energetic substrate utilization assessed by indirect calorimetry and mitochondrial respiration and biogenesis were evaluated. HFD led to fat mass increase, dyslipidemia, glucose intolerance and insulin resistance. ISO-1 did not alter these parameters. However, MIF inhibition was responsible for HFD-induced cardiac dysfunction worsening. Mouse capacity to increase oxygen consumption in response to exercise was reduced in HFD compared to ND, and further diminished in ISO-1-treated HFD group. Mitochondrial respiration was reduced in HFD mice, treated or not with ISO-1. Compared to ND, mitochondrial biogenesis signaling was upregulated in the HFD as demonstrated by mitochondrial DNA amount and PGC-1α expression. However, this increase in biogenesis was blocked by ISO-1 treatment.Conclusion
MIF inhibition achieved by ISO-1 was responsible for a reduction in HFD-induced mitochondrial biogenesis signaling that could explain majored cardiac dysfunction observed in HFD mice treated with MIF inhibitor. 相似文献995.
Anthony Delaune Armelle Cabin-Flaman Guillaume Legent David Gibouin Caroline Smet-Nocca Fabrice Lefebvre Arndt Benecke Marc Vasse Camille Ripoll 《PloS one》2013,8(2)
Imaging single proteins within cells is challenging if the possibility of artefacts due to tagging or to recognition by antibodies is to be avoided. It is generally believed that the biological properties of proteins remain unaltered when 14N isotopes are replaced with 15N. 15N-enriched proteins can be localised by dynamic Secondary Ion Mass Spectrometry (D-SIMS). We describe here a novel imaging analysis algorithm to detect a few 15N-enriched proteins - and even a single protein - within a cell using D-SIMS. The algorithm distinguishes statistically between a low local increase in 15N isotopic fraction due to an enriched protein and a stochastic increase due to the background. To determine the number of enriched proteins responsible for the increase in the isotopic fraction, we use sequential D-SIMS images in which we compare the measured isotopic fractions to those expected if 1, 2 or more enriched proteins are present. The number of enriched proteins is the one that gives the best fit between the measured and the expected values. We used our method to localise 15N-enriched thymine DNA glycosylase (TDG) and retinoid X receptor α (RXRα) proteins delivered to COS-7 cells. We show that both a single TDG and a single RXRα can be detected. After 4 h incubation, both proteins were found mainly in the nucleus; RXRα as a monomer or dimer and TDG only as a monomer. After 7 h, RXRα was found in the nucleus as a monomer, dimer or tetramer, whilst TDG was no longer in the nucleus and instead formed clusters in the cytoplasm. After 24 h, RXRα formed clusters in the cytoplasm, and TDG was no longer detectable. In conclusion, single unmodified proteins in cells can be counted and localised with 50 nm resolution by combining D-SIMS with our method of analysis. 相似文献
996.
Alexandra Gouazé Xavier Brenachot Caroline Rigault Alice Krezymon Camille Rauch Emmanuelle Nédélec Aleth Lemoine Jean Gascuel Sylvian Bauer Luc Pénicaud Alexandre Benani 《PloS one》2013,8(8)
The hypothalamus plays a crucial role in the control of the energy balance and also retains neurogenic potential into adulthood. Recent studies have reported the severe alteration of the cell turn-over in the hypothalamus of obese animals and it has been proposed that a neurogenic deficiency in the hypothalamus could be involved in the development of obesity. To explore this possibility, we examined hypothalamic cell renewal during the homeostatic response to dietary fat in mice, i.e., at the onset of diet-induced obesity. We found that switching to high-fat diet (HFD) accelerated cell renewal in the hypothalamus through a local, rapid and transient increase in cell proliferation, peaking three days after introducing the HFD. Blocking HFD-induced cell proliferation by central delivery of an antimitotic drug prevented the food intake normalization observed after HFD introduction and accelerated the onset of obesity. This result showed that HFD-induced dividing brain cells supported an adaptive anorectic function. In addition, we found that the percentage of newly generated neurons adopting a POMC-phenotype in the arcuate nucleus was increased by HFD. This observation suggested that the maturation of neurons in feeding circuits was nutritionally regulated to adjust future energy intake. Taken together, these results showed that adult cerebral cell renewal was remarkably responsive to nutritional conditions. This constituted a physiological trait required to prevent severe weight gain under HFD. Hence this report highlighted the amazing plasticity of feeding circuits and brought new insights into our understanding of the nutritional regulation of the energy balance. 相似文献
997.
998.
Louise Rossignol Camille Pelat Bruno Lambert Antoine Flahault Emmanuel Chartier-Kastler Thomas Hanslik 《PloS one》2013,8(10)
Background
Despite the fact that urinary tract infection (UTI) is a very frequent disease, little is known about its seasonality in the community.Methods and Findings
To estimate seasonality of UTI using multiple time series constructed with available proxies of UTI. Eight time series based on two databases were used: sales of urinary antibacterial medications reported by a panel of pharmacy stores in France between 2000 and 2012, and search trends on the Google search engine for UTI-related terms between 2004 and 2012 in France, Germany, Italy, the USA, China, Australia and Brazil. Differences between summers and winters were statistically assessed with the Mann-Whitney test. We evaluated seasonality by applying the Harmonics Product Spectrum on Fast Fourier Transform. Seven time series out of eight displayed a significant increase in medication sales or web searches in the summer compared to the winter, ranging from 8% to 20%. The eight time series displayed a periodicity of one year. Annual increases were seen in the summer for UTI drug sales in France and Google searches in France, the USA, Germany, Italy, and China. Increases occurred in the austral summer for Google searches in Brazil and Australia.Conclusions
An annual seasonality of UTIs was evidenced in seven different countries, with peaks during the summer. 相似文献999.
Lise Denoeud-Ndam Camille Fourcade Aurore Ogouyemi-Hounto Angèle Azon-Kouanou Marcelline d'Almeida Alain Azondékon Marouf J. Alao Véronique Dossou-Gbété Aldric Afangnihoun Pierre-Marie Girard Michel Cot Djimon-Marcel Zannou 《PloS one》2013,8(3)
Objective
To investigate the factors associated with HIV1 RNA plasma viral load (pVL) below 40 copies/mL at the third trimester of pregnancy, as part of prevention of mother-to-child transmission (PMTCT) in Benin.Design
Sub study of the PACOME clinical trial of malaria prophylaxis in HIV-infected pregnant women, conducted before and after the implementation of the WHO 2009 revised guidelines for PMTCT.Methods
HIV-infected women were enrolled in the second trimester of pregnancy. Socio-economic characteristics, HIV history, clinical and biological characteristics were recorded. Malaria prevention and PMTCT involving antiretroviral therapy (ART) for mothers and infants were provided. Logistic regression helped identifying factors associated with virologic suppression at the end of pregnancy.Results
Overall 217 third trimester pVLs were available, and 71% showed undetectability. Virologic suppression was more frequent in women enrolled after the change in PMTCT recommendations, advising to start ART at 14 weeks instead of 28 weeks of pregnancy. In multivariate analysis, Fon ethnic group (the predominant ethnic group in the study area), regular job, first and second pregnancy, higher baseline pVL and impaired adherence to ART were negative factors whereas higher weight, higher antenatal care attendance and longer ART duration were favorable factors to achieve virologic suppression.Conclusions
This study provides more evidence that ART has to be initiated before the last trimester of pregnancy to achieve an undetectable pVL before delivery. In Benin, new recommendations supporting early initiation were well implemented and, together with a high antenatal care attendance, led to high rate of virologic control. 相似文献1000.
Camille Duval Phillip Cassey Paul G. Lovell Ivan Mik?ík S. James Reynolds Karen A. Spencer 《PloS one》2013,8(12)
Reproduction is a critical period for birds as they have to cope with many stressful events. One consequence of an acute exposure to stress is the release of corticosterone, the avian stress hormone. Prolonged stress can have negative impacts on the immune system, resulting in, for example, increased oxidative stress. Through maternal effects, females are known to modulate their investment in eggs content according to their own physiological condition. Less is known about maternal investment in eggshells, especially in pigments. The two main eggshell pigments may possess opposite antioxidant properties: protoporphyrin (brown) is a pro-oxidant, whereas biliverdin (blue-green) is an antioxidant. In Japanese quail, we know that the deposition of both pigments is related to female body condition. Thus, a chronic stress response may be reflected in eggshell coloration. Using female Japanese quails that lay brown-spotted eggs, we explored whether physiological exposure to corticosterone induces a change in female basal stress and antioxidant factors, and eggshell pigment concentration, spectrophotometric reflectance, and maculation coverage. We supplemented adult females over a 2 week period with either peanut oil (control) or corticosterone (treatment). We collected pre- and post-supplementation eggs and analysed the effect of corticosterone treatment on female physiology and eggshell appearance parameters. Except for corticosterone-fed birds which laid eggs with brighter spots, supplementation had no significant effect on female physiology or eggshell pigment concentration, reflectance and maculation. The change in eggshell spot brightness was not detected by a photoreceptor noise-limited color opponent model of avian visual perception. Our data confirms that eggshell reflectance in spotted eggs varies over the laying sequence, and spot reflectance may be a key factor that is affected by females CORT exposure, even if the changes are not detected by an avian visual model. 相似文献