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51.
Jean-sebastien Casalegno Karine Le Bail Carval Daniel Eibach Marie-Laure Valdeyron Gery Lamblin Hervé Jacquemoud Georges Mellier Bruno Lina Pascal Gaucherand Patrice Mathevet Yahia Mekki 《PloS one》2012,7(10)
Background
Endocavity ultrasound is seen as a harmless procedure and has become a common gynaecological procedure. However without correct disinfection, it may result in nosocomial transmission of genito-urinary pathogens, such as high-risk Human Papillomavirus (HR-HPV). We aimed to evaluate the currently recommended disinfection procedure for covered endocavity ultrasound probes, which consists of “Low Level Disinfection” (LLD) with “quaternary ammonium compounds” containing wipes.Methods
From May to October 2011 swabs were taken from endovaginal ultrasound probes at the Gynecology Department of the Lyon University Hospital. During the first phase (May–June 2011) samples were taken after the ultrasound examination and after the LLD procedure. In a second phase (July–October 2011) swab samples were collected just before the probe was used. All samples were tested for the presence of human DNA (as a marker for a possible transmission of infectious pathogens from the genital tract) and HPV DNA with the Genomica DNA microarray (35 different HPV genotypes).Results
We collected 217 samples before and 200 samples after the ultrasound examination. The PCR was inhibited in two cases. Human DNA was detected in 36 (18%) post-examination samples and 61 (28%) pre-examination samples. After the ultrasound LLD procedure, 6 (3.0%) samples contained HR-HPV types (16, 31, 2×53 and 58). Similarly, HPV was detected in 6 pre-examination samples (2.7%). Amongst these 4 (1.9%) contained HR-HPV (types 53 and 70).Conclusion
Our study reveals that a considerable number of ultrasound probes are contaminated with human and HR-HPV DNA, despite LLD disinfection and probe cover. In all hospitals, where LLD is performed, the endovaginal ultrasound procedure must therefore be considered a source for nosocomial HR-HPV infections. We recommend the stringent use of high-level disinfectants, such as glutaraldehyde or hydrogen peroxide solutions. 相似文献52.
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Frange P Meyer L Deveau C Tran L Goujard C Ghosn J Girard PM Morlat P Rouzioux C Chaix ML;French ANRS CO PRIMO Cohort Study Group 《PloS one》2012,7(2):e31695
Objective
To analyse the contribution of primary human immunodeficiency virus type 1 (HIV-1) infection (PHI) to the French viral epidemic.Methods
HIV-1 pol sequences included 987 PHI from the French ANRS PRIMO cohort between 1999 and 2010 and were analysed using a population-based phylogenetic approach. Clinical features, risk factors, sexual behaviour and drug resistance for clustered and nonclustered transmission events were ascertained.Results
Viruses from 125 (12.7%) of PHI cosegregated into 56 transmission chains, with increasing frequency during the last years (10.2% before 2006 versus 15.2% of clusters in 2006–2010, p = 0.02). The mean number of patients per cluster was 2.44. Compared to unique PHI, clusters involved more often men, infected through homosexual intercourse, of young age, with a high number of casual sexual partnerships and frequent previous HIV serological tests. Resistant strains were found in 16.0% and 11.1% of clusters and unique PHI, respectively (p = 0.11). Overall, 34% (n = 19) clusters included patients followed in French regions far apart, involving 13 clusters with at least one Parisian patient.Conclusions
PHIs are a significant source of onward transmission, especially in the MSM population. Recently infected people contribute to the spread of the viral epidemic throughout the French territory. Survey of transmitted drug resistance and behavioural characteristics of patients involved into clustered PHI may help to guide prevention and treatment interventions. 相似文献56.
Tavernier ML Petit E Lesur D Wadouachi A Courtois B Courtois J Michaud P 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,863(2):266-272
Ion-exchange chromatography has been applied to purification of unsaturated oligoglucuronans. After an isocratic elution on a strong anion-exchange column, the collected fractions were desalted by low pressure size exclusion chromatography. However, this efficient separation was limited by the time required to desalt. So, we developed a reversed-phase chromatography method using back ionization of oligomers. Two C18 columns were tested with trifluoroacetic acid (TFA 0.7%) as eluent. Different selectivities and column stabilities were observed in this acidic condition. The scale up for semi-preparative applications enabled us to recover pure unsaturated oligoglucuronans without desalting step. 相似文献
57.
Bogdanik L Framery B Frölich A Franco B Mornet D Bockaert J Sigrist SJ Grau Y Parmentier ML 《PloS one》2008,3(4):e2084
Background
The Dystrophin-glycoprotein complex (DGC) comprises dystrophin, dystroglycan, sarcoglycan, dystrobrevin and syntrophin subunits. In muscle fibers, it is thought to provide an essential mechanical link between the intracellular cytoskeleton and the extracellular matrix and to protect the sarcolemma during muscle contraction. Mutations affecting the DGC cause muscular dystrophies. Most members of the DGC are also concentrated at the neuromuscular junction (NMJ), where their deficiency is often associated with NMJ structural defects. Hence, synaptic dysfunction may also intervene in the pathology of dystrophic muscles. Dystroglycan is a central component of the DGC because it establishes a link between the extracellular matrix and Dystrophin. In this study, we focused on the synaptic role of Dystroglycan (Dg) in Drosophila.Methodology/Principal Findings
We show that Dg was concentrated postsynaptically at the glutamatergic NMJ, where, like in vertebrates, it controls the concentration of synaptic Laminin and Dystrophin homologues. We also found that synaptic Dg controlled the amount of postsynaptic 4.1 protein Coracle and alpha-Spectrin, as well as the relative subunit composition of glutamate receptors. In addition, both Dystrophin and Coracle were required for normal Dg concentration at the synapse. In electrophysiological recordings, loss of postsynaptic Dg did not affect postsynaptic response, but, surprisingly, led to a decrease in glutamate release from the presynaptic site.Conclusion/Significance
Altogether, our study illustrates a conservation of DGC composition and interactions between Drosophila and vertebrates at the synapse, highlights new proteins associated with this complex and suggests an unsuspected trans-synaptic function of Dg. 相似文献58.
Maisse C Rossin A Cahuzac N Paradisi A Klein C Haillot ML Hérincs Z Mehlen P Hueber AO 《Experimental cell research》2008,314(14):2544-2552
UNC5H receptors (UNC5H1, UNC5H2, UNC5H3) are putative tumor suppressors whose expression is lost in numerous cancers. These receptors have been shown to belong to the so-called family of dependence receptors. Such receptors induce apoptosis when their ligand netrin-1 is absent, thus conferring a state of cellular dependence towards ligand presence. Along this line, these receptors may limit tumor progression because they induce the death of tumor cells that grow in settings of ligand unavailability. We show here that UNC5H receptors are localized to cholesterol-and sphingolipid-enriched membrane domains called lipid rafts. We then demonstrate that the lipid raft localization of UNC5H2 is required for the pro-apoptotic activity of unbound UNC5H2. We also propose that this lipid raft localization is probably mediated via the recruitment of adaptor protein(s) within the death domain of UNC5H2 but is not dependent on the post-translational modification by palmitoylation of UNC5H2 even though this palmitoylation is required for UNC5H2 pro-apoptotic activity. Moreover we show that the interaction of UNC5H2 with the downstream pro-apoptotic serine threonine kinase DAPk is dependent on both UNC5H2 lipid raft localization and palmitoylation. Thus, we propose that the UNC5H dependence receptors require lipid raft localization and palmitoylation to trigger apoptosis. 相似文献
59.
Simulation of potential range expansion of oak disease caused by Phytophthora cinnamomi under climate change 总被引:1,自引:0,他引:1
Magali Bergot Emmanuel Cloppet Victorine Pérarnaud† Michel Déqué‡ Benoît Marçais§ Marie-Laure Desprez-Loustau¶ 《Global Change Biology》2004,10(9):1539-1552
This study examines the effects of climate warming on one of the most widely distributed and destructive forest pathogens, Phytophthora cinnamomi. In Europe, the winter survival of the pathogen is the dominant cue for the development of the disease it causes to oaks, especially Quercus robur and Q. rubra. The potential pathogen and disease geographic ranges were compared in France between two reference periods, 1968–1998 and 2070–2099. Simulations were obtained by combining a physiologically based approach predicting the pathogen winter survival in relation to microhabitat temperature (in the phloem of infected trees) with a regionalized climatic scenario derived from a global circulation model. Positive anomalies in winter temperatures calculated with this scenario were in the range 0.5–5°C between the periods 2070–2099 and the 1968–1998, according to sites and months. As a consequence, higher annual rates of P. cinnamomi survival were predicted, resulting in a potential range expansion of the disease of one to a few hundred kilometers eastward from the Atlantic coast within one century. Based on this example, the study emphasizes the need of a better understanding of the impacts of global change on the biotic constraint constituted by plant pathogens. 相似文献
60.