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31.
32.
Iris Marangon Nicole Boggetto Cécilia Ménard-Moyon Nathalie Luciani Claire Wilhelm Alberto Bianco Florence Gazeau 《Journal of visualized experiments : JoVE》2013,(82)
Carbon-based nanomaterials, like carbon nanotubes (CNTs), belong to this type of nanoparticles which are very difficult to discriminate from carbon-rich cell structures and de facto there is still no quantitative method to assess their distribution at cell and tissue levels. What we propose here is an innovative method allowing the detection and quantification of CNTs in cells using a multispectral imaging flow cytometer (ImageStream, Amnis). This newly developed device integrates both a high-throughput of cells and high resolution imaging, providing thus images for each cell directly in flow and therefore statistically relevant image analysis. Each cell image is acquired on bright-field (BF), dark-field (DF), and fluorescent channels, giving access respectively to the level and the distribution of light absorption, light scattered and fluorescence for each cell. The analysis consists then in a pixel-by-pixel comparison of each image, of the 7,000-10,000 cells acquired for each condition of the experiment. Localization and quantification of CNTs is made possible thanks to some particular intrinsic properties of CNTs: strong light absorbance and scattering; indeed CNTs appear as strongly absorbed dark spots on BF and bright spots on DF with a precise colocalization.This methodology could have a considerable impact on studies about interactions between nanomaterials and cells given that this protocol is applicable for a large range of nanomaterials, insofar as they are capable of absorbing (and/or scattering) strongly enough the light. 相似文献
33.
Wolfgang Retz Samir S. T. Boureghda Petra Retz-Junginger Florence Philipp-Wiegmann Michael Rösler 《Attention deficit and hyperactivity disorders》2013,5(1):47-57
ADHD and psychopathy are both associated with poor social adaptation and antisocial behavior. Previous studies have also suggested that ADHD and psychopathy share some symptomatology. The current study attempted to further uncover the relationship between ADHD and psychopathy in perpetrators by investigating the possibility of underlying common factors of ADHD and psychopathy using standardized instruments. Correlation analyses and principal component analyses were performed on ADHD-SB self-rating questionnaires and the PCL-SV from a population of 314 offenders. Further, subjects without ADHD, full ADHD and partially remitted ADHD according to DSM-IV were compared regarding psychopathic traits. ADHD and psychopathy rating scores were found to be correlated. Only psychopathic features related to unstable and antisocial lifestyle, but not related to affective features of psychopathy accounted to this association. Findings on the principal component analysis suggest that ADHD and psychopathy are unrelated on a symptomatic level, with the exception of impulsivity, which is a common feature that seems to combine both constructs. 相似文献
34.
Background
Chlamydia and genital human papillomavirus (HPV) are the two most common sexually transmitted infections (STIs) among teens and young adults in industrialised countries. The majority of adolescents, however, have limited or no knowledge of these infections. Within the context of a cross-sectional survey on awareness and knowledge of sexually transmitted infections, secondary school students attending the 8th grade and above in Bremen and Bremerhaven, two cities in northern Germany, were asked to rate the risk of peers to get infected with HIV, HPV or chlamydia.Methods
Between October and December 2011, students aged 12–20 years completed an anonymous, self-administered questionnaire at their school. In addition to answering questions on awareness and knowledge of sexually transmitted infections, all students were also asked to rate the risk of peers to get infected with HIV, HPV or chlamydia. Furthermore, those reporting ever having sexual intercourse were asked to rate their own risk of getting infected with each of the three infections.Results
1,148 students, 55% female, completed the questionnaire. 27% of the students reported having had sexual intercourse. 68% of all students rated the risk of same-aged students to get infected with HIV/AIDS as high/medium. The corresponding proportions for HPV and chlamydia were 19 and 25% respectively. Those reporting ever having sexual intercourse generally perceived their own risk of getting infected with HIV, chlamydia or HPV as lower than that of their peers.Conclusion
Generally, the risk of getting infected with HIV was perceived as being higher than that of getting infected with HPV or chlamydia, most likely due to the fact that the students were more aware of HIV than of the other two infections. Efforts should be made to improve awareness and knowledge of HPV and chlamydia among school going adolescents, and to make them realize that these are common infections that are preventable. 相似文献35.
Sanya Fanous Danielle H. Guez‐Barber Evan M. Goldart Regina Schrama Florence R. M. Theberge Yavin Shaham Bruce T. Hope 《Journal of neurochemistry》2013,124(1):100-108
Cue‐induced heroin seeking after prolonged withdrawal is associated with neuronal activation and altered gene expression in prefrontal cortex (PFC). However, these previous studies assessed gene expression in all neurons regardless of their activity state during heroin seeking. Using Fos as a marker of neural activity, we describe distinct molecular alterations induced in activated versus non‐activated neurons during cue‐induced heroin seeking after prolonged withdrawal. We trained rats to self‐administer heroin for 10 days (6 h/day) and assessed cue‐induced heroin seeking in extinction tests after 14 or 30 days. We used fluorescent‐activated cell sorting (FACS) to purify Fos‐positive and Fos‐negative neurons from PFC 90 min after extinction testing. Flow cytometry showed that Fos‐immunoreactivity was increased in less than 10% of sparsely distributed PFC neurons. mRNA levels of the immediate early genes fosB, arc, egr1, and egr2, as well as npy and map2k6, were increased in Fos‐positive, but not Fos‐negative, neurons. In support of these findings, double‐label immunohistochemistry indicated substantial coexpression of neuropeptide Y (NPY)‐ and Arc‐immunoreactivity in Fos‐positive neurons. Our data indicate that cue‐induced relapse to heroin seeking after prolonged withdrawal induces unique molecular alterations within activated PFC neurons that are distinct from those observed in the surrounding majority of non‐activated neurons. 相似文献
36.
Florence Schaffner Naho Yokota Tatiana Carneiro-Lobo Maki Kitano Michael Schaffer G. Mark Anderson Barbara M. Mueller Charles T. Esmon Wolfram Ruf 《PloS one》2013,8(4)
Several markers identify cancer stem cell-like populations, but little is known about the functional roles of stem cell surface receptors in tumor progression. Here, we show that the endothelial protein C receptor (EPCR), a stem cell marker in hematopoietic, neuronal and epithelial cells, is crucial for breast cancer growth in the orthotopic microenvironment of the mammary gland. Mice with a hypomorphic allele of EPCR show reduced tumor growth in the PyMT-model of spontaneous breast cancer development and deletion of EPCR in established PyMT tumor cells significantly attenuates transplanted tumor take and growth. We find expansion of EPCR+ cancer stem cell-like populations in aggressive, mammary fat pad-enhanced human triple negative breast cancer cells. In this model, EPCR-expressing cells have markedly increased mammosphere- and tumor-cell initiating activity compared to another stable progenitor-like subpopulation present at comparable frequency. We show that receptor blocking antibodies to EPCR specifically attenuate in vivo tumor growth initiated by either EPCR+ cells or the heterogenous mixture of EPCR+ and EPCR- cells. Furthermore, we have identified tumor associated macrophages as a major source for recognized ligands of EPCR, suggesting a novel mechanism by which cancer stem cell-like populations are regulated by innate immune cells in the tumor microenvironment. 相似文献
37.
Sonia Gaucher Isabelle Boutron Florence Marchand-Maillet Gabriel Baron Richard Douard Jean-Pierre Béthoux AMBUPROG Group Investigators 《PloS one》2016,11(2)
Objectives
To assess the impact of a standardized pre-operative telephone checklist on the rate of late cancellations of ambulatory surgery (AMBUPROG trial).Design
Multicenter, two-arm, parallel-group, open-label randomized controlled trial.Setting
11 university hospital ambulatory surgery units in Paris, France.Participants
Patients scheduled for ambulatory surgery and able to be reached by telephone.Intervention
A 7-item checklist designed to prevent late cancellation, available in five languages and two versions (for children and adults), was administered between 7 and 3 days before the planned date of surgery, by an automated phone system or a research assistant. The control group received standard management alone.Main Outcome Measures
Rate of cancellation on the day of surgery or the day before.Results
The study population comprised 3900 patients enrolled between November 2012 and September 2013: 1950 patients were randomized to the checklist arm and 1950 patients to the control arm. The checklist was administered to 68.8% of patients in the intervention arm, 1002 by the automated phone system and 340 by a research assistant. The rate of late cancellation did not differ significantly between the checklist and control arms (109 (5.6%) vs. 113 (5.8%), adjusted odds ratio [95% confidence interval] = 0.91 [0.65–1.29], (p = 0.57)). Checklist administration revealed that 355 patients (28.0%) had not undergone tests ordered by the surgeon or anesthetist, and that 254 patients (20.0%) still had questions concerning the fasting state.Conclusions
A standardized pre-operative telephone checklist did not avoid late cancellations of ambulatory surgery but enabled us to identify several frequent causes.Trial Registration
ClinicalTrials.gov NCT01732159相似文献38.
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40.
A headspace solid‐phase microextraction (HS‐SPME) method combined with gas chromatography‐mass spectrometry (GC/MS) was developed and optimized for the extraction and the analysis of volatile organic compounds (VOCs) from lavandin and fine lavender roots. Optimal parameters to extract volatile molecules from ground and intact roots were determined using a divinylbenzene‐carboxen‐polydimethylsiloxane (DVB/CAR/PDMS) coating fiber at 70 °C for 60 min. A total of 99 VOCs, including 40 monoterpenoids, 15 sesquiterpenoids, 1 diterpenoid and 2 coumarins were detected. The main compounds detected in lavandin roots were fenchol, borneol, and coumarin. Performances of the optimized SPME GC/MS method were evaluated via the comparison of VOC emissions between roots from different cultivars of fine lavender (7713 and maillette) and lavandin (abrial and grosso). Chemometric analysis, using partial least squares‐discriminant analysis (PLS‐DA), suggests fifteen significant features as potential discriminatory compounds. Among them, β‐phellandrene allows discrimination between lavender and lavandin varieties. 相似文献