319 research outputs found
Genome-wide analyses of light-regulated genes in Aspergillus nidulans reveal a complex interplay between different photoreceptors and novel photoreceptor functions
Fungi sense light of different wavelengths using blue-, green-, and red-light photoreceptors. Blue light sensing requires the “white-collar” proteins with flavin as chromophore, and red light is sensed through phytochrome. Here we analyzed genome-wide gene expression changes caused by short-term, low-light intensity illumination with blue-, red- or far-red light in Aspergillus nidulans and found that more than 1100 genes were differentially regulated. The largest number of up- and downregulated genes depended on the phytochrome FphA and the attached HOG pathway. FphA and the white-collar orthologue LreA fulfill activating but also repressing functions under all light conditions and both appear to have roles in the dark. Additionally, we found about 100 genes, which are red-light induced in the absence of phytochrome, suggesting alternative red-light sensing systems. We also found blue-light induced genes in the absence of the blue-light receptor LreA. We present evidence that cryptochrome may be part of this regulatory cue, but that phytochrome is essential for the response. In addition to in vivo data showing that FphA is involved in blue-light sensing, we performed spectroscopy of purified phytochrome and show that it responds indeed to blue light
Reactive oxygen species and nuclear factor-kappa B pathway mediate high glucose-induced Pax-2 gene expression in mouse embryonic mesenchymal epithelial cells and kidney explants
Diabetic mellitus confers a major risk of congenital malformations, and is associated with diabetic embryopathy, affecting multiple organs including the kidney. The DNA paired box-2 (Pax-2) gene is essential in nephrogenesis. We investigated whether high glucose alters Pax-2 gene expression and aimed to delineate its underlying mechanism(s) of action using both in vitro (mouse embryonic mesenchymal epithelial cells (MK4) and ex vivo (kidney explant from Hoxb7-green florescent protein (GFP) mice) approaches. Pax-2 gene expression was determined by reverse transcriptase-polymerase chain reaction, Western blotting, and immunofluorescent staining. A fusion gene containing the full-length 5′-flanking region of the human Pax-2 promoter linked to a luciferase reporter gene, pGL-2/hPax-2, was transfected into MK4 cells with or without dominant negative IκBα (DN IκBα) cotransfection. Fusion gene expression level was quantified by cellular luciferase activity. Reactive oxygen species (ROS) generation was measured by lucigenin assay. Embryonic kidneys from Hoxb7-GFP mice were cultured ex vivo. High D(+) glucose (25mM), compared to normal glucose (5mM), specifically induced Pax-2 gene expression in MK4 cells and kidney explants. High glucose-induced Pax-2 gene expression is mediated, at least in part, via ROS generation and activation of the nuclear factor kappa B signaling pathway, but not via protein kinase C, p38 mitogen-activated protein kinase (MAPK), and p44/42 MAPK signaling
The Microtubule-Targeting Agent Pretubulysin Impairs the Inflammatory Response in Endothelial Cells by a JNK-Dependent Deregulation of the Histone Acetyltransferase Brd4
The anti-inflammatory effects of depolymerizing microtubule-targeting agents on
leukocytes are known for a long time, but the potential involvement of the vascular endothelium and the underlying mechanistic basis is still largely unclear. Using the recently synthesized depolymerizing microtubule-targeting agent pretubulysin, we investigated the antiinflammatory potential of pretubulysin and other microtubule-targeting agents with respect to
the TNF-induced leukocyte adhesion cascade in endothelial cells, to improve our understanding
of the underlying biomolecular background. We found that treatment with pretubulysin reduces
inflammation in vivo and in vitro via inhibition of the TNF-induced adhesion of leukocytes to
the vascular endothelium by down-regulation of the pro-inflammatory cell adhesion molecules
ICAM-1 and VCAM-1 in a JNK-dependent manner. The underlying mechanism includes
JNK-induced deregulation and degradation of the histone acetyltransferase Bromodomaincontaining protein 4. This study shows that depolymerizing microtubule-targeting agents, in
addition to their established effects on leukocytes, also significantly decrease the inflammatory
activation of vascular endothelial cells. These effects are not based on altered pro-inflammatory
signaling cascades, but require deregulation of the capability of cells to enter constructive
transcription for some genes, setting a baseline for further research on the prominent antiinflammatory effects of depolymerizing microtubule-targeting agents
Single-cell profiling of myasthenia gravis identifies a pathogenic T cell signature.
Myasthenia gravis (MG) is an autoimmune disease characterized by impaired neuromuscular signaling due to autoantibodies targeting the acetylcholine receptor. Although its auto-antigens and effector mechanisms are well defined, the cellular and molecular drivers underpinning MG remain elusive. Here, we employed high-dimensional single-cell mass and spectral cytometry of blood and thymus samples from MG patients in combination with supervised and unsupervised machine-learning tools to gain insight into the immune dysregulation underlying MG. By creating a comprehensive immune map, we identified two dysregulated subsets of inflammatory circulating memory T helper (Th) cells. These signature ThCD103 and ThGM cells populated the diseased thymus, were reduced in the blood of MG patients, and were inversely correlated with disease severity. Both signature Th subsets rebounded in the blood of MG patients after surgical thymus removal, indicative of their role as cellular markers of disease activity. Together, this in-depth analysis of the immune landscape of MG provides valuable insight into disease pathogenesis, suggests novel biomarkers and identifies new potential therapeutic targets for treatment
Opt-out as an acceptable method of obtaining consent in medical research: a short report
<p>Abstract</p> <p>Background</p> <p>A prospective cohort study was set up to investigate a possible association between antibiotic prescribing and antibiotic resistance of <it>E. coli </it>urinary tract infection in the community. Participation of patients with urinary tract infection was obtained through an opt-out methodology. This short paper reports on the acceptability of the opt-out recruitment approach.</p> <p>Methods</p> <p>Participating practices (22) were requested to send a urine sample from all patients presenting with symptoms of urinary tract infection. Upon receipt of the sample in the laboratory, a letter explaining the study, an opt-out form and a freepost envelope were sent to all adult patients. A website with additional information and including an 'opt-out' button was set up for the study.</p> <p>Results</p> <p>A total of 1362 urine samples were submitted by the 22 participating practices representing 1178 adult patients of whom 193 actively responded to the letter: 142 opted out by letter, 15 through the website, 2 by phone and 12 sent the letter back without indication, making a total of 171 patients or 14.5% opt-out; the remaining 22 patients (1.9%) explicitly opted in. The total group consisted of 80% women and the mean age was 50.9 years (sd 20.8). No significant differences were found between patients who participated and those who opted out in terms of age, gender or whether the urine sample was positive or not.</p> <p>Conclusions</p> <p>Overall the opt-out method was well received and participation in the study reached 85.5%. The low number of complaints (2) indicates that this is a generally acceptable method of patient recruitment. The 14.5% opt-out shows that it effectively empowers patients to decline participation. The similarity between patients opting out and the rest of the patients is reassuring for extrapolation of the results of the study.</p
Self-persuasion as marketing technique: the role of consumers’ involvement
Purpose
This paper aims to demonstrate that self-persuasion can be used as a marketing technique to increase consumers’ generosity and that the efficacy of this approach is dependent on consumers’ involvement with target behavior.
Design/methodology/approach
An experimental field-study was conducted to investigate the effects of self-persuasion versus direct persuasion attempts versus no persuasion attempts on consumers’ tipping behavior in a lunchroom. Additionally, in a lab experiment, the moderating role of involvement on self-persuasion versus direct persuasion was tested.
Findings
The results reveal that self-persuasion is more effective than direct persuasion attempts or no persuasive messages in increasing consumers’ generosity. This is moderated by consumers’ involvement with the target behavior. For consumers with high involvement, self-persuasion is more effective than direct persuasion, while no differences were found for consumers with moderate or low involvement.
Practical implications
The scope of self-persuasion is not limited to the inhibition of undesired behavior, but it also extends to the facilitation of desired behavior, which considerably broadens the scope of this technique. Self-persuasion might be used as a marketing technique to influence consumers’ purchase behavior. This might be particularly viable in situations in which consumers feel high involvement with products or behavior.
Originality/value
Recently, research in health psychology demonstrated that self-persuasion is a very effective way of inhibiting undesired, addictive behavior and being more successful than direct persuasion. Yet, insufficient knowledge is available about the efficacy of self-persuasion with regard to promoting other target behaviors. In particular, its potential as a marketing technique to influence consumers’ behavior and its boundary conditions are still understudied
Mapping Oil and Gas Development Potential in the US Intermountain West and Estimating Impacts to Species
Many studies have quantified the indirect effect of hydrocarbon-based economies on climate change and biodiversity, concluding that a significant proportion of species will be threatened with extinction. However, few studies have measured the direct effect of new energy production infrastructure on species persistence. in the western US and translate the build-out scenarios into estimated impacts on sage-grouse. We project that future oil and gas development will cause a 7–19 percent decline from 2007 sage-grouse lek population counts and impact 3.7 million ha of sagebrush shrublands and 1.1 million ha of grasslands in the study area.Maps of where oil and gas development is anticipated in the US Intermountain West can be used by decision-makers intent on minimizing impacts to sage-grouse. This analysis also provides a general framework for using predictive models and build-out scenarios to anticipate impacts to species. These predictive models and build-out scenarios allow tradeoffs to be considered between species conservation and energy development prior to implementation
Novel conserved domains in proteins with predicted roles in eukaryotic cell-cycle regulation, decapping and RNA stability
BACKGROUND: The emergence of eukaryotes was characterized by the expansion and diversification of several ancient RNA-binding domains and the apparent de novo innovation of new RNA-binding domains. The identification of these RNA-binding domains may throw light on the emergence of eukaryote-specific systems of RNA metabolism. RESULTS: Using sensitive sequence profile searches, homology-based fold recognition and sequence-structure superpositions, we identified novel, divergent versions of the Sm domain in the Scd6p family of proteins. This family of Sm-related domains shares certain features of conventional Sm domains, which are required for binding RNA, in addition to possessing some unique conserved features. We also show that these proteins contain a second previously uncharacterized C-terminal domain, termed the FDF domain (after a conserved sequence motif in this domain). The FDF domain is also found in the fungal Dcp3p-like and the animal FLJ22128-like proteins, where it fused to a C-terminal domain of the YjeF-N domain family. In addition to the FDF domains, the FLJ22128-like proteins contain yet another divergent version of the Sm domain at their extreme N-terminus. We show that the YjeF-N domains represent a novel version of the Rossmann fold that has acquired a set of catalytic residues and structural features that distinguish them from the conventional dehydrogenases. CONCLUSIONS: Several lines of contextual information suggest that the Scd6p family and the Dcp3p-like proteins are conserved components of the eukaryotic RNA metabolism system. We propose that the novel domains reported here, namely the divergent versions of the Sm domain and the FDF domain may mediate specific RNA-protein and protein-protein interactions in cytoplasmic ribonucleoprotein complexes. More specifically, the protein complexes containing Sm-like domains of the Scd6p family are predicted to regulate the stability of mRNA encoding proteins involved in cell cycle progression and vesicular assembly. The Dcp3p and FLJ22128 proteins may localize to the cytoplasmic processing bodies and possibly catalyze a specific processing step in the decapping pathway. The explosive diversification of Sm domains appears to have played a role in the emergence of several uniquely eukaryotic ribonucleoprotein complexes, including those involved in decapping and mRNA stability
NMR-Spectroscopy for Nontargeted Screening and Simultaneous Quantification of Health-Relevant Compounds in Foods: The Example of Melamine
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