Objective: Interleukin (IL)-31 is a recently discovered helical cytokine. Its receptor consists of a ligand-specific IL-31 receptor (IL-31R) subunit and a receptor chain that is shared with Oncostatin M (OSM), called OSM-Rbeta. Because OSM-Rbeta-deficient animals have reduced hematopoietic progenitor cells (HPC) and OSM has effects on and is involved in homeostasis of HPC, we studied whether IL-31 and IL-31R play a role in hematopoiesis.
View Article and Find Full Text PDFPure Na0.44MnO2 samples were prepared via a solid-state route by carefully tuning the synthesis conditions. Insertion/deinsertion of sodium into the well-crystallized particles leads to capacities as high as 140 mA.
View Article and Find Full Text PDFInterleukin (IL) 31Ralpha (glycoprotein 130-like monocyte receptor and glycoprotein 130-like receptor) heterodimerizes with oncostatin M receptor beta to bind IL-31, a cytokine expressed preferentially by CD4(+) T helper type 2 (Th2) cells. However, the functions of IL-31-IL-31R signaling in immune regulation remain unknown. Here, we identify a novel role for IL-31R in limiting type 2 inflammation in the lung.
View Article and Find Full Text PDFA proteomic approach has been used to study changes in leaf protein content from plants transformed for alcohol dehydrogenase (ADH) activity. Individual quantitative analysis of 190-436 spots separated by two-dimensional electrophoresis was performed, and spots displaying significant quantitative changes between control (C), sense (S), and antisense (R) transformants were selected using Student's t test. Of the 14 spots selected and further analyzed after trypsic digestion, 9 could be identified by MS analysis and 5 by LC-MS/MS.
View Article and Find Full Text PDFHaploinsufficiency of Dll4, a vascular-specific Notch ligand, has shown that it is essential for embryonic vascular development and arteriogenesis. Mechanistically, it is unclear how the Dll4-mediated Notch pathway contributes to complex vascular processes that demand meticulous coordination of multiple signalling pathways. Here we show that Dll4-mediated Notch signalling has a unique role in regulating endothelial cell proliferation and differentiation.
View Article and Find Full Text PDFSirolimus is an immunosuppressive drug currently used alone or in combination with cyclosporine. Both drugs undergo extensive metabolism by the CYP 3A enzymes. This study aimed at comparing the activity of recombinant CYP (rCYP) 3A4 and 3A5 toward sirolimus, investigating the effect of cyclosporine on the metabolic rate of these two cytochromes P450 (P450s), as well as the impact of the CYP 3A5*3 polymorphism on that of human liver microsomes (HLMs).
View Article and Find Full Text PDFSeveral key signalling pathways, such as Hedgehog, Notch, Wnt and BMP-TGFbeta-Activin (bone morphogenetic protein-transforming growth factor-beta-Activin), are involved in most processes essential to the proper development of an embryo. It is also becoming increasingly clear that these pathways can have a crucial role in tumorigenesis when reactivated in adult tissues through sporadic mutations or other mechanisms. We will focus here on the Hedgehog pathway, which is abnormally activated in most basal cell carcinomas, and discuss potential therapeutic opportunities offered by the progress made in understanding this signalling pathway.
View Article and Find Full Text PDFThe Hedgehog (Hh) pathway is a signaling cascade that directs patterning in most animals and is crucial for proper development. At the molecular level, Hh ligands drive cell proliferation in some cell types while causing others to undergo differentiation. Hh signaling is most active during embryogenesis, and aberrant reactivation of the pathway in adult tissue can lead to the development of cancer.
View Article and Find Full Text PDFSignal transduction pathways are frequently found to repress transcription of target genes in the absence of stimulation and, conversely, to upregulate transcription in the presence of a signal. Transcription factors are central in this dual regulatory mechanism and widely use a generalized mechanism to repress transcription through recruitment of a Sin3-histone deacetylase (HDAC) complex to their binding sites on DNA. The protein SAP18 (Sin3-associated polypeptide of 18 kDa) has been shown to play a key role in gene-specific recruitment of the HDAC complex by a number of transcription factors including Gli, GAGA, and Bicoid.
View Article and Find Full Text PDFFusion of citrus diploid parental protoplasts generates allotetraploid hybrids which do not retain their parental traits with regard to leaf aroma compound biosynthesis. The aim of this study was thus to examine hybrid leaf proteomes in comparison with their parents. Leaf soluble proteins from two citrus allotetraploid hybrids (mandarin + lime and mandarin + kumquat) and their diploid parents (mandarin, lime, and kumquat) were submitted to 2-D gel electrophoresis.
View Article and Find Full Text PDFInterleukin 27 (IL-27) was first characterized as a proinflammatory cytokine with T helper type 1-inducing activity. However, subsequent work has demonstrated that mice deficient in IL-27 receptor (IL-27R alpha) show exacerbated inflammatory responses to a variety of challenges, suggesting that IL-27 has important immunoregulatory functions in vivo. Here we demonstrate that IL-27R alpha-deficient mice were hypersusceptible to experimental autoimmune encephalomyelitis and generated more IL-17-producing T helper cells.
View Article and Find Full Text PDFBackground: In clinical and forensic toxicology, general unknown screening is used to detect and identify exogenous compounds. In this study, we aimed to develop a comprehensive general unknown screening method based on liquid chromatography coupled with a hybrid triple-quadrupole linear ion trap mass spectrometer.
Methods: After solid-phase extraction, separation was performed using gradient reversed-phase chromatography.
We report on the study of the electrochemically targeted complexation/expulsion of a metal cation (Ba2+) by a crown ether tetra(thiomethyl)tetrathiafulvalene derivative (crown-TTM-TTF). Real time, in situ FTIR spectroelectrochemistry was used to obtain spectroscopic evidence of this electrochemically triggered phenomenon. Density functional theory calculations allowed the spectral information collected to be assigned.
View Article and Find Full Text PDFThe paper proposes a model explaining the spatial variation in incidence of nephropathia epidemica in Europe. We take into account the rodent dynamic features and the replicative dynamics of the virus in animals, high in the acute phase of newly infected animals and low in the subsequent chronic phase. The model revealed that only vole populations with multi-annual fluctuations allow for simultaneously high numbers of infected rodents and high proportions of those rodents in the acute excretion phase during the culminating phase of population build-up.
View Article and Find Full Text PDFBackground: Commonly used methods for detecting benzodiazepines (BZPs) and BZP-like substances, such as zolpidem and zopiclone, may not detect low concentrations of these drugs. We developed a liquid chromatographic-tandem mass spectrometric method for identifying these drugs and their relevant metabolites.
Methods: We extracted BZPs from urine by solid-phase extraction with a mixed-mode phase (OASIS HLB cartridges).
Antidepressants belong to a variety of chemical and pharmacologic classes. Most require therapeutic drug monitoring, at least in certain circumstances, such as unexplained inefficacy or suspected toxicity. Several types of chromatographic methods have generally been used.
View Article and Find Full Text PDFThe interleukin-27 (IL-27)/T-cell cytokine receptor (TCCR) pathway plays an important role in development of protective immunity against cutaneous leishmaniasis caused by Leishmania major. In this study, we analyzed the role of IL-27/TCCR pathway in the host defense against visceral leishmaniasis (VL) by monitoring the course of L. donovani infection in TCCR-deficient C57BL/6 (TCCR-/-) mice.
View Article and Find Full Text PDFAlthough the ability of IL-27 to promote T cell responses is well documented, the anti-inflammatory properties of this cytokine remain poorly understood. The current work demonstrates that during infection with Toxoplasma gondii, IL-27R-deficient mice generate aberrant IL-2 responses that are associated with the development of a lethal inflammatory disease. Because in vivo depletion of IL-2 prolongs the survival of infected IL-27R-/- mice, these data suggest that IL-27 curbs the development of immunopathology by limiting parasite-induced IL-2 production.
View Article and Find Full Text PDFNotch pathway is crucial for stem/progenitor cell maintenance, growth and differentiation in a variety of tissues. Using a transgenic cell ablation approach, we found in our previous study that cells expressing Notch1 are crucial for prostate early development and re-growth. Here, we further define the role of Notch signaling in regulating prostatic epithelial cell growth and differentiation using biochemical and genetic approaches in ex vivo or in vivo systems.
View Article and Find Full Text PDFTo identify genes that could serve as targets for novel cancer therapeutics, we used a bioinformatic analysis of microarray data comparing gene expression between normal and tumor-derived primary human tissues. From this approach, we have found that maternal embryonic leucine zipper kinase (Melk), a member of the AMP serine/threonine kinase family, exhibits multiple features consistent with the potential utility of this gene as an anticancer target. An oligonucleotide microarray analysis of multiple human tumor samples and cell lines suggests that Melk expression is frequently elevated in cancer relative to normal tissues, a pattern confirmed by quantitative reverse transcription-PCR and Western blotting of selected primary tumor samples.
View Article and Find Full Text PDFThe Drosophila Fused (Fu) kinase is an integral component of the Hedgehog (Hh) pathway that helps promote Hh-dependent gene transcription. Vertebrate homologues of Fu function in the Hh pathway in vitro, suggesting that Fu is evolutionarily conserved. We have generated fused (stk36) knockout mice to address the in vivo function of the mouse Fu (mFu) homologue.
View Article and Find Full Text PDFIn order to improve protein assignment from peptide mass fingerprints (PMF) in species with incompletely sequenced genomes, the genus-specific mutations deduced from Expressed sequence tag (EST) sequences were included in the complete reading frames of orthologous proteins, resulting in a new searchable in silico protein database. Using this method in tests on four plant species, the MOWSE score of at least 20% more proteins was improved compared to conventional approaches on crude, total proteins, for middle-sized EST projects. Larger contigs are assembled in more important EST projects and this improves the conventional assignment of the most abundant proteins.
View Article and Find Full Text PDFPrevious reports have focused on the ability of IL-27 to promote naive T cell responses but the present study reveals that surface expression of WSX-1, the ligand-specific component of the IL-27R, is low on these cells and that highest levels are found on effector and memory CD4(+) and CD8(+) T cells. Accordingly, during infection with Toxoplasma gondii, in vivo T cell activation is associated with enhanced expression of WSX-1, and, in vitro, TCR ligation can induce expression of WSX-1 regardless of the polarizing (Th1/Th2) environment present at the time of priming. However, while these data establish that mitogenic stimulation promotes expression of WSX-1 by T cells, activation of NK cells and NKT cells prompts a reduction in WSX-1 levels during acute toxoplasmosis.
View Article and Find Full Text PDFPrevious studies have demonstrated that mice null (-/-) for either CD34 or c-mpl are viable and have greatly decreased numbers of multipotential (CFU-Mix), erythroid (BFU-E), and granulocytemacrophage (CFU-GM) progenitor cells in the bone marrow (BM), spleen (Spl) and peripheral blood (PB), without noticeable decreases in the nucleated cellularity of these organs. To evaluate the significance of these two proteins further, mice null for both CD34 and c-mpl were assessed for hematopoietic progenitor cells (HPC) and nucleated cellularity and compared with these cells in CD34-/- and c-mpl-/- mice. The following progenitors were assessed: CFU-GM, BFU-E, CFU-Mix with an erythroid component, CFU-Mix with erythroid and megakaryocyte components, nonerythroid CFU with a megakaryocyte (Meg) component and pure CFU-Meg.
View Article and Find Full Text PDFMyelodysplastic syndrome (MDS) comprises a heterogeneous group of often fatal hematopoietic stem cell disorders for which neither curative nor standard treatment exists. The complex karyotypes and multistep nature of MDS have severely restricted the identification of causative genetic mutations and thus limited insight into new and more effective therapies. Here we describe a zebrafish mutant crimsonless (crs) with a developmental blood defect that closely recapitulates the ineffective hematopoiesis of MDS including anemia, dysplasia, increased blood cell apoptosis, and multilineage cytopenia.
View Article and Find Full Text PDF