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991.
Odile Launay Anne Krivine Caroline Charlier Van Truster Vassilis Tsatsaris Jacques Lepercq Yves Ville Carolyn Avenell Thibaut Andrieu Flore Rozenberg Florence Artiguebielle Jean-Marc Tréluyer Fran?ois Goffinet Inserm COFLUPREG Study Group 《PloS one》2012,7(12)
Background
In 2009, pregnant women were specifically targeted by a national vaccination campaign against pandemic A/H1N1 influenza virus. The objectives of the COFLUPREG study, initially set up to assess the incidence of serious forms of A/H1N1 influenza, were to assess the consequences of maternal vaccination on pregnancy outcomes and maternal seroprotection at delivery.Methods
Pregnant women, between 12 and 35 weeks of gestation, non vaccinated against A/H1N1 2009 influenza were randomly selected to be included in a prospective cohort study conducted in three maternity centers in Paris (France) during pandemic period. Blood samples were planned to assess hemagglutination inhibition (HI) antibody against A/H1N1 2009 influenza at inclusion and at delivery.Results
Among the 877 pregnant women included in the study, 678 (77.3%) had serum samples both at inclusion and delivery, and 320 (36.5%) received pandemic A/H1N1 2009 influenza vaccine with a median interval between vaccination and delivery of 92 days (95% CI 48–134). At delivery, the proportion of women with seroprotection (HI antibodies titers against A/H1N1 2009 influenza of 1∶40 or greater) was 69.9% in vaccinated women. Of the 422 non-vaccinated women with serological data, 11 (2.6%; 95%CI: 1.3–4.6) had laboratory documented A/H1N1 2009 influenza (1 with positive PCR and 10 with serological seroconversion). None of the 877 study’s women was hospitalized for flu. No difference on pregnancy outcomes was evidenced between vaccinated women, non-vaccinated women without seroconversion and non-vaccinated women with flu.Conclusion
Despite low vaccine coverage, incidence of pandemic flu was low in this cohort of pregnant women.No effect on pregnancy and delivery outcomes was evidenced after vaccination. 相似文献992.
The transketolase (TKT) enzyme in Mycobacterium tuberculosis
represents a novel drug target for tuberculosis treatment and has low homology
with the orthologous human enzyme. Here, we report on the structural and kinetic
characterization of the transketolase from M. tuberculosis
(TBTKT), a homodimer whose monomers each comprise 700 amino acids. We show that
TBTKT catalyses the oxidation of donor sugars xylulose-5-phosphate and
fructose-6-phosphate as well as the reduction of the acceptor sugar
ribose-5-phosphate. An invariant residue of the TKT consensus sequence required
for thiamine cofactor binding is mutated in TBTKT; yet its catalytic activities
are unaffected, and the 2.5 Å resolution structure of full-length TBTKT
provides an explanation for this. Key structural differences between the human
and mycobacterial TKT enzymes that impact both substrate and cofactor
recognition and binding were uncovered. These changes explain the kinetic
differences between TBTKT and its human counterpart, and their differential
inhibition by small molecules. The availability of a detailed structural model
of TBTKT will enable differences between human and M.
tuberculosis TKT structures to be exploited to design selective
inhibitors with potential antitubercular activity. 相似文献
993.
A Ho-Pun-Cheung H Bazin N Gaborit C Larbouret P Garnero E Assenat F Castan C Bascoul-Mollevi J Ramos M Ychou A Pèlegrin G Mathis E Lopez-Crapez 《PloS one》2012,7(7):e37065
Following the development of targeted therapies against EGFR and HER2, two members of the human epidermal receptor (HER) family of receptor tyrosine kinases, much interest has been focused on their expression in tumors. However, knowing the expression levels of individual receptors may not be sufficient to predict drug response. Here, we describe the development of antibody-based time-resolved Förster resonance energy transfer (TR-FRET) assays for the comprehensive analysis not only of EGFR and HER2 expression in tumor cryosections, but also of their activation through quantification of HER homo- or heterodimers. First, EGFR and HER2 expression levels were quantified in 18 breast tumors and the results were compared with those obtained by using reference methods. The EGFR number per cell determined by TR-FRET was significantly correlated with EGFR mRNA copy number (P<0.0001). Moreover, our method detected HER2 overexpression with 100% specificity and sensibility, as confirmed by the standard IHC, FISH and qPCR analyses. EGFR and HER2 dimerization was then assessed, using as controls xenograft tumors from cell lines with known dimer expression profiles. Our results show that quantification of HER dimerization provides information about receptor activation that cannot be obtained by quantification of single receptors. Quantifying HER expression and dimerization by TR-FRET assays might help identifying novel clinical markers for optimizing patients’ treatment in oncology. 相似文献
994.
Background
Although premature neonates (PN) gut microbiota has been studied, data about gut clostridial colonization in PN are scarce. Few studies have reported clostridia colonization in PN whereas Bacteroides and bifidobacteria have been seldom isolated. Such aberrant gut microbiota has been suggested to be a risk factor for the development of intestinal infections. Besides, PN are often treated by broad spectrum antibiotics, but little is known about how antibiotics can influence clostridial colonization based on their susceptibility patterns. The aim of this study was to report the distribution of Clostridium species isolated in feces from PN and to determine their antimicrobial susceptibility patterns. Additionally, clostridial colonization perinatal determinants were analyzed.Results
Of the 76 PN followed until hospital discharge in three French neonatal intensive care units (NICUs), 79% were colonized by clostridia. Clostridium sp. colonization, with a high diversity of species, increased throughout the hospitalization. Antibiotic courses had no effect on the clostridial colonization incidence although strains were found susceptible (except C. difficile) to anti-anaerobe molecules tested. However, levels of colonization were decreased by either antenatal or neonatal (during more than 10 days) antibiotic courses (p = 0.006 and p = 0.001, respectively). Besides, incidence of colonization was depending on the NICU (p = 0.048).Conclusion
This study shows that clostridia are part of the PN gut microbiota. It provides for the first time information on the status of clostridia antimicrobial susceptibility in PN showing that strains were susceptible to most antibiotic molecules. Thus, the high prevalence of this genus is not linked to a high degree of resistance to antimicrobial agents or to the use of antibiotics in NICUs. The main perinatal determinant influencing PN clostridia colonization appears to be the NICU environment. 相似文献995.
Appaix F Girod S Boisseau S Römer J Vial JC Albrieux M Maurin M Depaulis A Guillemain I van der Sanden B 《PloS one》2012,7(4):e35169
Fluorescent staining of astrocytes without damaging or interfering with normal brain functions is essential for intravital microscopy studies. Current methods involved either transgenic mice or local intracerebral injection of sulforhodamine 101. Transgenic rat models rarely exist, and in mice, a backcross with GFAP transgenic mice may be difficult. Local injections of fluorescent dyes are invasive. Here, we propose a non-invasive, specific and ubiquitous method to stain astrocytes in vivo. This method is based on iv injection of sulforhodamine dyes and is applicable on rats and mice from postnatal age to adulthood. The astrocytes staining obtained after iv injection was maintained for nearly half a day and showed no adverse reaction on astrocytic calcium signals or electroencephalographic recordings in vivo. The high contrast of the staining facilitates the image processing and allows to quantify 3D morphological parameters of the astrocytes and to characterize their network. Our method may become a reference for in vivo staining of the whole astrocytes population in animal models of neurological disorders. 相似文献
996.
Rubach MP Mukemba J Florence S John B Crookston B Lopansri BK Yeo TW Piera KA Alder SC Weinberg JB Anstey NM Granger DL Mwaikambo ED 《PloS one》2012,7(5):e35985
Plasma Plasmodium falciparum histidine-rich protein-2 (PfHRP-2) concentrations, a measure of parasite biomass, have been correlated with malaria severity in adults, but not yet in children. We measured plasma PfHRP-2 in Tanzanian children with uncomplicated (n = 61) and cerebral malaria (n = 45; 7 deaths). Median plasma PfHRP-2 concentrations were higher in cerebral malaria (1008 [IQR 342-2572] ng/mL) than in uncomplicated malaria (465 [IQR 36-1426] ng/mL; p = 0.017). In cerebral malaria, natural log plasma PfHRP-2 was associated with coma depth (r = -0.42; p = 0.006) and mortality (OR: 3.0 [95% CI 1.03-8.76]; p = 0.04). In this relatively small cohort study in a mesoendemic transmission area of Africa, plasma PfHRP-2 was associated with pediatric malaria severity and mortality. Further studies among children in areas of Africa with higher malaria transmission and among children with different clinical manifestations of severe malaria will help determine the wider utility of quantitative PfHRP-2 as a measure of parasite biomass and prognosis in sub-Saharan Africa. 相似文献
997.
Kempf M Rolain JM Diatta G Azza S Samb B Mediannikov O Gassama Sow A Diene SM Fenollar F Raoult D 《PloS one》2012,7(6):e39495
Incidence of carbapenem-resistant Acinetobacter baumannii is rising in several parts of the world. In Africa, data concerning this species and its resistance to carbapenems are limited. The objective of the present study was to identify the presence of A. baumannii carbapenem-resistant encoding genes in natural reservoirs in Senegal, where antibiotic pressure is believed to be low. From October 2010 to January 2011, 354 human head lice, 717 human fecal samples and 118 animal fecal samples were screened for the presence of A. baumannii by real time PCR targeting bla(OXA51-like) gene. For all samples positive for A. baumannii, the carbapenemase-hydrolysing oxacillinases bla(OXA23-like) and bla(OXA24-like) were searched for and sequenced, and the isolates harbouring an oxacillinase were genotyped using PCR amplification and sequencing of recA gene. The presence of A. baumannii was detected in 4.0% of the head lice, in 5.4% of the human stool samples and in 5.1% of the animal stool samples tested. No bla(OXA24) gene was detected but six fecal samples and three lice were positive for bla(OXA23-like) gene. The bla(OXA23-like) gene isolated in lice was likely a new oxacillinase sequence. Finally, the A. baumannii detected in stools were all of recA genotype 3 and those detected in lice, of recA genotype 4. This study shows for the first time a reservoir of bla(OXA23-like)-positive gene in human head lice and stool samples in Senegal. 相似文献
998.
Expression profiling of human immune cell subsets identifies miRNA-mRNA regulatory relationships correlated with cell type specific expression 总被引:1,自引:0,他引:1
999.
Oppliger LV Correa JA Engelen AH Tellier F Vieira V Faugeron S Valero M Gomez G Destombe C 《PloS one》2012,7(6):e39289
A major determinant of the geographic distribution of a species is expected to be its physiological response to changing abiotic variables over its range. The range of a species often corresponds to the geographic extent of temperature regimes the organism can physiologically tolerate. Many species have very distinct life history stages that may exhibit different responses to environmental factors. In this study we emphasized the critical role of the haploid microscopic stage (gametophyte) of the life cycle to explain the difference of edge distribution of two related kelp species. Lessonia nigrescens was recently identified as two cryptic species occurring in parapatry along the Chilean coast: one located north and the other south of a biogeographic boundary at latitude 29-30°S. Six life history traits from microscopic stages were identified and estimated under five treatments of temperature in eight locations distributed along the Chilean coast in order to (1) estimate the role of temperature in the present distribution of the two cryptic L. nigrescens species, (2) compare marginal populations to central populations of the two cryptic species. In addition, we created a periodic matrix model to estimate the population growth rate (λ) at the five temperature treatments. Differential tolerance to temperature was demonstrated between the two species, with the gametophytes of the Northern species being more tolerant to higher temperatures than gametophytes from the south. Second, the two species exhibited different life history strategies with a shorter haploid phase in the Northern species contrasted with considerable vegetative growth in the Southern species haploid stage. These results provide strong ecological evidence for the differentiation process of the two cryptic species and show local adaptation of the life cycle at the range limits of the distribution. Ecological and evolutionary implications of these findings are discussed. 相似文献
1000.
Sandrine Le Guillou Nezha Sdassi Johann Laubier Bruno Passet Marthe Vilotte Johan Castille Denis Lalo? Jacqueline Polyte Stéphan Bouet Florence Jaffrézic Edmond-Paul Cribiu Jean-Luc Vilotte Fabienne Le Provost 《PloS one》2012,7(9)