205 research outputs found

    Gene induction during differentiation of human monocytes into dendritic cells: an integrated study at the RNA and protein levels

    Get PDF
    Changes in gene expression occurring during differentiation of human monocytes into dendritic cells were studied at the RNA and protein levels. These studies showed the induction of several gene classes corresponding to various biological functions. These functions encompass antigen processing and presentation, cytoskeleton, cell signalling and signal transduction, but also an increase in mitochondrial function and in the protein synthesis machinery, including some, but not all, chaperones. These changes put in perspective the events occurring during this differentiation process. On a more technical point, it appears that the studies carried out at the RNA and protein levels are highly complementary.Comment: website publisher: http://www.springerlink.com/content/ha0d2c351qhjhjdm

    Effects of nanoparticles on murine macrophages

    Get PDF
    Metallic nanoparticles are more and more widely used in an increasing number of applications. Consequently, they are more and more present in the environment, and the risk that they may represent for human health must be evaluated. This requires to increase our knowledge of the cellular responses to nanoparticles. In this context, macrophages appear as an attractive system. They play a major role in eliminating foreign matter, e.g. pathogens or infectious agents, by phagocytosis and inflammatory responses, and are thus highly likely to react to nanoparticles. We have decided to study their responses to nanoparticles by a combination of classical and wide-scope approaches such as proteomics. The long term goal of this study is the better understanding of the responses of macrophages to nanoparticles, and thus to help to assess their possible impact on human health. We chose as a model system bone marrow-derived macrophages and studied the effect of commonly used nanoparticles such as TiO2 and Cu. Classical responses of macrophage were characterized and proteomic approaches based on 2D gels of whole cell extracts were used. Preliminary proteomic data resulting from whole cell extracts showed different effects for TiO2-NPs and Cu-NPs. Modifications of the expression of several proteins involved in different pathways such as, for example, signal transduction, endosome-lysosome pathway, Krebs cycle, oxidative stress response have been underscored. These first results validate our proteomics approach and open a new wide field of investigation for NPs impact on macrophagesComment: Nanosafe2010: International Conference on Safe Production and Use of Nanomaterials 16-18 November 2010, Grenoble, France, Grenoble : France (2010

    Establishment of proteome reference maps for somatic and zygotic embryos of Cyclamen persicum mill.

    Get PDF
    Comprehensive proteomic characterizations were performed aiming to create proteome reference maps for somatic and zygotic embryos of Cyclamen persicum. Separation by two dimensional isoelectric focusing - sodium dodecyl sulfate polyacrylamide gel electrophoresis led to a resolution of more than 800 protein spots for each tissue. Approximately 70% of the spots likewise appeared in both zygotic and in somatic embryo's protein fractions. However, differential gel electrophoresis analyses revealed pronounced differences in abundances for the majority of proteins present in both tissues. MS analyses for 300 reproducible spots in total (263 of the zygotic embryos' protein fraction and 37 spots appearing specifically in the somatic embryos' proteome) led to identification of 261 proteins, 35 of which were specific or highly abundant in gels of the somatic embryo's tissue. Most identified proteins were found to be involved in glycolysis or gluconeogenesis and stress response pathways

    Towards a better understanding of somatic embryogenesis in Cyclamen persicum

    Get PDF
    Somatic embryogenesis in Cyclamen persicum was first reported in 1984 and has potential applications for propagation and breeding of this economically important ornamental crop. This in vitro regeneration system can be used for vegetative propagation of parental lines of F1 hybrids and elite plants, production of artificial seeds, Agrobacterium tumefaciens-mediated genetic transformation, long-term cryopreservation, protoplast to plant regeneration and somatic hybridization. Somatic embryogenesis was shown to be a powerful propagation system for some C. persicum genotypes, but commercial application in large scale so far is hindered by several limitations, i.e., asynchronous development, malformations or secondary somatic embryogenesis. However, recent molecular approaches by transcriptomic and proteomic analyses were undertaken in order to better understand and control this in vitro regeneration system and to overcome these problems. Our studies aim at comparing somatic embryos to their zygotic counterparts regarding their proteomes. Protein separation by two dimensional isoelectric focusing - sodium do-decyl sulfate polyacrylamide gel electrophoresis led to a resolution of about 1000 protein spots per gel, of which the first 253 were identified by mass spectrometry. Most were found to be involved in glycolysis/gluconeogenesis and stress response pathways. A proteome reference map of zygotic embryos will be publicly released soon and may serve as a basis for further investigations and improvements of somatic embryogenesis

    Mild psychotic experiences among ethnic minority and majority adolescents and the role of ethnic density

    Get PDF
    Despite evidence of the increased risk of psychotic disorders among ethnic minority adults, little is known about the effect of ethnic minority status to mild psychotic experiences among adolescents. This study investigated mild psychotic experiences in ethnic minority and majority adolescents in a Dutch representative general population sample, and tested the ethnic density effect in the classroom.The CAPE was used to assess mild psychotic experiences among Dutch (n = 3,606) and non-Western ethnic minority pupils (n = 769).Ethnic minority adolescents showed higher levels of grandiosity and delusions than their ethnic majority peers, whereas no differences were found for hallucinations, paranormal beliefs and paranoia between both groups of adolescents. The ethnic density effect was partly confirmed for the ethnic majority: a decrease of ethnic majority pupils in class increased their feelings of paranoia.Because only some dimensions of mild psychotic experiences were affected by ethnic minority status or the interaction between ethnic minority status and ethnic class composition, our findings emphasize that mild psychotic experiences are multifactorial in origin, with different underlying processes.</p

    The relationship between mental disorders and actual and desired subjective social status

    Get PDF
    Mental disorders are associated with lower subjective social status (SSS), but a more nuanced understanding of this relationship is needed. We examined the influence of disorder age of onset and recency on SSS and studied whether mental disorders are also associated with the discrepancy between actual and desired SSS.Method Data are from the baseline and second wave of the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2). Mental disorders were assessed with the Composite International Diagnostic Interview (CIDI 3.0), while both actual and desired SSS were assessed with a ten-rung ladder. Linear regression was used to examine the association between mental disorders and SSS.Results Of 5303 participants, 2237 had a lifetime mental disorder at baseline. These participants reported significantly lower actual SSS (6.28) at follow-up than healthy participants (6.66, B = -0.38 [95% CI -0.48 to -0.27], p < 0.001) and a significantly greater actual-desired SSS discrepancy (1.14 v. 1.05 after controlling for actual SSS, B = 0.09 [0.01-0.17], p = 0.024). Lower age of onset of the first mental disorder was marginally significantly associated with lower actual SSS (B = 0.006 [0.000-0.012], p = 0.046). More recent disorders were also associated with lower actual SSS (B = 0.015 [0.005-0.026], p = 0.005), such that participants whose disorder remitted a ≥6 years before baseline were statistically indistinguishable from healthy participants.Conclusions Lifetime mental disorders are associated with lower actual SSS and a slightly greater discrepancy between actual and desired SSS. However, people with mental disorders in (long-term) remission have a similar social status as healthy participants

    The GPI transamidase complex of Saccharomyces cerevisiae contains Gaa1p, Gpi8p, and Gpi16p

    Get PDF
    Gpi8p and Gaa1p are essential components of the GPI transamidase that adds glycosylphosphatidylinositols (GPIs) to newly synthesized proteins. After solubilization in 1.5% digitonin and separation by blue native PAGE, Gpi8p is found in 430-650-kDa protein complexes. These complexes can be affinity purified and are shown to consist of Gaa1p, Gpi8p, and Gpi16p (YHR188c). Gpi16p is an essential N-glycosylated transmembrane glycoprotein. Its bulk resides on the lumenal side of the ER, and it has a single C-terminal transmembrane domain and a small C-terminal, cytosolic extension with an ER retrieval motif. Depletion of Gpi16p results in the accumulation of the complete GPI lipid CP2 and of unprocessed GPI precursor proteins. Gpi8p and Gpi16p are unstable if either of them is removed by depletion. Similarly, when Gpi8p is overexpressed, it largely remains outside the 430-650-kDa transamidase complex and is unstable. Overexpression of Gpi8p cannot compensate for the lack of Gpi16p. Homologues of Gpi16p are found in all eucaryotes. The transamidase complex is not associated with the Sec61p complex and oligosaccharyltransferase complex required for ER insertion and N-glycosylation of GPI proteins, respectively. When GPI precursor proteins or GPI lipids are depleted, the transamidase complex remains intact

    Non-Markovian stochastic Schr\"odinger equations: Generalization to real-valued noise using quantum measurement theory

    Full text link
    Do stochastic Schr\"odinger equations, also known as unravelings, have a physical interpretation? In the Markovian limit, where the system {\em on average} obeys a master equation, the answer is yes. Markovian stochastic Schr\"odinger equations generate quantum trajectories for the system state conditioned on continuously monitoring the bath. For a given master equation, there are many different unravelings, corresponding to different sorts of measurement on the bath. In this paper we address the non-Markovian case, and in particular the sort of stochastic \sch equation introduced by Strunz, Di\' osi, and Gisin [Phys. Rev. Lett. 82, 1801 (1999)]. Using a quantum measurement theory approach, we rederive their unraveling which involves complex-valued Gaussian noise. We also derive an unraveling involving real-valued Gaussian noise. We show that in the Markovian limit, these two unravelings correspond to heterodyne and homodyne detection respectively. Although we use quantum measurement theory to define these unravelings, we conclude that the stochastic evolution of the system state is not a true quantum trajectory, as the identity of the state through time is a fiction.Comment: 17 pages, 3 figure

    Endogenous Morphine Levels Are Increased in Sepsis: A Partial Implication of Neutrophils

    Get PDF
    BACKGROUND: Mammalian cells synthesize morphine and the respective biosynthetic pathway has been elucidated. Human neutrophils release this alkaloid into the media after exposure to morphine precursors. However, the exact role of endogenous morphine in inflammatory processes remains unclear. We postulate that morphine is released during infection and can be determined in the serum of patients with severe infection such as sepsis. METHODOLOGY: The presence and subcellular immunolocalization of endogenous morphine was investigated by ELISA, mass spectrometry analysis and laser confocal microscopy. Neutrophils were activated with Interleukin-8 (IL-8) or lipopolysaccharide (LPS). Morphine secretion was determined by a morphine-specific ELISA. mu opioid receptor expression was assessed with flow cytometry. Serum morphine concentrations of septic patients were determined with a morphine-specific ELISA and morphine identity was confirmed in human neutrophils and serum of septic patients by mass spectrometry analysis. The effects of the concentration of morphine found in serum of septic patients on LPS-induced release of IL-8 by human neutrophils were tested. PRINCIPAL FINDINGS: We confirmed the presence of morphine in human neutrophil extracts and showed its colocalisation with lactoferrin within the secondary granules of neutrophils. Morphine secretion was quantified in the supernatant of activated human polymorphonuclear neutrophils in the presence and absence of Ca(2+). LPS and IL-8 were able to induce a significant release of morphine only in presence of Ca(2+). LPS treatment increased mu opioid receptor expression on neutrophils. Low concentration of morphine (8 nM) significantly inhibited the release of IL-8 from neutrophils when coincubated with LPS. This effect was reversed by naloxone. Patients with sepsis, severe sepsis and septic shock had significant higher circulating morphine levels compared to patients with systemic inflammatory response syndrome and healthy controls. Mass spectrometry analysis showed that endogenous morphine from serum of patient with sepsis was identical to poppy-derived morphine. CONCLUSIONS: Our results indicate that morphine concentrations are increased significantly in the serum of patients with systemic infection and that morphine is, at least in part, secreted from neutrophils during sepsis. Morphine concentrations equivalent to those found in the serum of septic patients significantly inhibited LPS-induced IL-8 secretion in neutrophils
    • …
    corecore