27 research outputs found
Ca(2+)-mediated mitochondrial ROS metabolism augments Wnt/β-catenin pathway activation to facilitate cell differentiation
Emerging evidence suggests that reactive oxygen species (ROS) can stimulate Wnt/{beta}-catenin pathway in a number of cellular processes. However, potential sources of endogenous ROS have not been thoroughly explored. Here, we show that growth factor depletion in human neural progenitor cells induces ROS production in mitochondria. Elevated ROS levels augment activation of Wnt/{beta}-catenin signaling that regulates neural differentiation. We find that growth factor depletion stimulates release of Ca(2+) from the endoplasmic reticulum stores that subsequently accumulates in the mitochondria and triggers ROS production. The inhibition of mitochondrial Ca(2+) uptake with simultaneous growth factor depletion prevents the rise in ROS metabolism. Moreover, low ROS levels block the dissociation of the Wnt effector Dishevelled from Nucleoredoxin. Attenuation of the response amplitudes of pathway effectors delays the onset of Wnt/{beta}-catenin pathway activation and results in markedly impaired neuronal differentiation. Our findings reveal Ca(2+)-mediated ROS metabolic cues that finetune the efficiency of cell differentiation by modulating the extent of the Wnt/{beta}-catenin signaling output
Investigations on DNA damage and frequency of micronuclei in occupational exposure to electromagnetic fields (EMFs) emitted from video display terminals (VDTs)
The potential effect of electromagnetic fields (EMFs) emitted from video display terminals (VDTs) to elicit biological response is a major concern for the public. The software professionals are subjected to cumulative EMFs in their occupational environments. This study was undertaken to evaluate DNA damage and incidences of micronuclei in such professionals. To the best of our knowledge, the present study is the first attempt to carry out cytogenetic investigations on assessing bioeffects in personal computer users. The study subjects (n = 138) included software professionals using VDTs for more than 2 years with age, gender, socioeconomic status matched controls (n = 151). DNA damage and frequency of micronuclei were evaluated using alkaline comet assay and cytochalasin blocked micronucleus assay respectively. Overall DNA damage and incidence of micronuclei showed no significant differences between the exposed and control subjects. With exposure characteristics, such as total duration (years) and frequency of use (minutes/day) sub-groups were assessed for such parameters. Although cumulative frequency of use showed no significant changes in the DNA integrity of the classified sub-groups, the long-term users (> 10 years) showed higher induction of DNA damage and increased frequency of micronuclei and micro nucleated cells
Granulocyte colony-stimulating factor treatment ameliorates lupus nephritis through the expansion of regulatory T cells
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the Creative Commons license, and indicate if changes were made.Abstract
Background
Granulocyte colony-stimulating factor (G-CSF) can induce regulatory T cells (Tregs) as well as myeloid-derived suppressor cells (MDSCs). Despite the immune modulatory effects of G-CSF, results of G-CSF treatment in systemic lupus erythematosus are still controversial. We therefore investigated whether G-CSF can ameliorate lupus nephritis and studied the underlying mechanisms.
Methods
NZB/W F1 female mice were treated with G-CSF or phosphate-buffered saline for 5 consecutive days every week from 24 weeks of age, and were analyzed at 36 weeks of age.
Results
G-CSF treatment decreased proteinuria and serum anti-dsDNA, increased serum complement component 3 (C3), and attenuated renal tissue injury including deposition of IgG and C3. G-CSF treatment also decreased serum levels of BUN and creatinine, and ultimately decreased mortality of NZB/W F1 mice. G-CSF treatment induced expansion of CD4+CD25+Foxp3+ Tregs, with decreased renal infiltration of T cells, B cells, inflammatory granulocytes and monocytes in both kidneys and spleen. G-CSF treatment also decreased expression levels of MCP-1, IL-6, IL-2, and IL-10 in renal tissues as well as serum levels of MCP-1, IL-6, TNF-α, IL-10, and IL-17. When Tregs were depleted by PC61 treatment, G-CSF-mediated protective effects on lupus nephritis were abrogated.
Conclusions
G-CSF treatment ameliorated lupus nephritis through the preferential expansion of CD4+CD25+Foxp3+ Tregs. Therefore, G-CSF has a therapeutic potential for lupus nephritis
Gene expression analysis of ELF-MF exposed human monocytes indicating the involvement of the alternative activation pathway
This study focused on the cell activating capacity of extremely low frequency magnetic fields (ELF-MF) on human umbilical cord blood-derived monocytes. Our results confirm the previous findings of cell activating capacity of ELF-MF (1.0 mT) in human monocytes, which was detected as an increased ROS release. Furthermore, gene expression profiling (whole-genome cDNA array Human Unigene RZPD-2) was performed to achieve a comprehensive view of involved genes during the cell activation process after 45 min ELF-MF exposure. Our results indicate the alteration of 986 genes involved in metabolism, cellular physiological processes, signal transduction and immune response. Significant regulations could be analyzed for 5 genes (expression >2- or <0.5-fold): IL15RA (Interleukin 15 receptor, alpha chain), EPS15R (Epidermal growth factor receptor pathway substrate 15 - like 1), DNMT3A (Hypothetical protein MGC16121), DNMT3A (DNA (cytosine-5) methyltransferase 3 alpha), and one gene with no match to known genes, DKFZP586J1624. Real-time RT-PCR analysis of the kinetic of the expression of IL15RA, and IL10RA during 45 min ELF-MF exposure indicates the regulation of cell activation via the alternative pathway, whereas the delayed gene expression of FOS, IL2RA and the melatonin synthesizing enzyme HIOMT suggests the suppression of inflammatory processes. Accordingly, we suggest that ELF-MF activates human monocytes via the alternative pathway
Streamlining Structured Data Markup and Agile Modelling Methods
Part 2: Short PapersInternational audienceStructured Data Markup allows Web developers to embed semantics in HTML pages, thus enabling clients (search engines, client apps etc.) to distil machine-readable resource descriptions from HTML code. This approach emerged from the Semantic Web paradigm as a powerful alternative to traditional Web scraping. Its enablers are dedicated HTML extensions (e.g., RDFa) and controlled vocabularies (e.g., Schema.org). Originating in a different context, Enterprise Modelling methods rely on diagrammatic means for describing and analysing an enterprise system in terms of key properties and conceptual abstractions. Hence, both the Semantic Web and Enterprise Modelling paradigms share a common interest in machine-processable semantics towards the goal of elevating semantics-awareness in information systems and decision support. Inspired by this overlapping, the paper proposes a mechanism for streamlining semantics between Structured Data Markup and enterprise modelling methods. Towards this goal, it employs the Resource Description Framework and the Agile Modelling Method Engineering Framework
Cyclosporine A Inhibits the T-bet-Dependent Antitumor Response of CD8+T Cells
Transplant recipients face an increased risk of cancer compared with the healthy population. Although several studies have examined the direct effects of immunosuppressive drugs on cancer cells, little is known about the interactions between pharmacological immunosuppression and cancer immunosurveillance. We investigated the different effects of rapamycin (Rapa) versus cyclosporine A (CsA) on tumor-reactive CD8(+) T cells. After adoptive transfer of CD8(+) T cell receptor-transgenic OTI T cells, recipient mice received either skin grafts expressing ovalbumin (OVA) or OVA-expressing B16F10 melanoma cells. Animals were treated daily with Rapa or CsA. Skin graft rejection and tumor growth as well as molecular and cellular analyses of skin- and tumor-infiltrating lymphocytes were performed. Both Rapa and CsA were equally efficient in prolonging skin graft survival when applied at clinically relevant doses. In contrast to Rapa-treated animals, CsA led to accelerated tumor growth in the presence of adoptively transferred tumor-reactive CD8(+) OTI T cells. Further analyses showed that T-bet was downregulated by CsA (but not Rapa) in CD8(+) T cells and that cancer cytotoxicity was profoundly inhibited in the absence of T-bet. CsA reduces T-bet-dependent cancer immunosurveillance by CD8(+) T cells. This may contribute to the increased cancer risk in transplant recipients receiving calcineurin inhibitors. The authors show that immunosuppressive treatment with cyclosporine A, but not rapamycin, decreases T-bet expression in tumor-reactive CD8+ T cells, which inhibits the immune response against developing melanomas in an antigen-specific mouse model
A Very Fast Decision Tree Algorithm for Real-Time Data Mining of Imperfect Data Streams in a Distributed Wireless Sensor Network
Wireless sensor networks (WSNs) are a rapidly emerging technology with a great potential in many ubiquitous applications. Although these sensors can be inexpensive, they are often relatively unreliable when deployed in harsh environments characterized by a vast amount of noisy and uncertain data, such as urban traffic control, earthquake zones, and battlefields. The data gathered by distributed sensors—which serve as the eyes and ears of the system—are delivered to a decision center or a gateway sensor node that interprets situational information from the data streams. Although many other machine learning techniques have been extensively studied, real-time data mining of high-speed and nonstationary data streams represents one of the most promising WSN solutions. This paper proposes a novel stream mining algorithm with a programmable mechanism for handling missing data. Experimental results from both synthetic and real-life data show that the new model is superior to standard algorithms
Digitalisation of Person-Oriented Services in the Field of Child and Youth Welfare: Design and Evaluation of an Information System Design
Personenbezogene Dienstleistungen in der Kinder- und Jugendhilfe stellen in Deutschland einen erheblichen Anteil der nachgefragten Dienstleistungen sowie einen bedeutenden Wirtschaftszweig dar. Sie zeichnen sich durch die Interaktion verschiedener Individuen innerhalb komplexer sozialer Prozesse aus. Dabei besteht im täglichen Arbeitsalltag die Herausforderung, schwach strukturierte Arbeitsprozesse, informelle Kommunikationsstrukturen sowie Erfahrungswissen so zu integrieren, dass einerseits eine bestmögliche persönliche Unterstützung der Klienten erreicht wird, andererseits individuelle und organisationale Arbeits- und Lernprozesse ermöglicht werden. Trotz der enormen Bedeutung der personenbezogenen Dienstleistungen existiert in diesem Bereich bisher keine adäquate Unterstützung der Arbeit durch dedizierte Informationssysteme, sodass vielfach auf Consumer-IT zurückgegriffen werden muss. Im vorliegenden Beitrag berichten wir daher über den Entwurf und die Evaluation eines branchenspezifischen Informationssystemdesigns zur Unterstützung personennaher Dienstleistungen im Bereich der Kinder- und Jugendhilfe. Zunächst werden in diesem Bereich die aus mehreren Quellen gewonnenen und zusammengeführten Anforderungen überblickartig vorgestellt. Auf deren Grundlage wird schließlich die Gestaltung eines Informationssystems vollzogen. Der Systemvorschlag wird anschließend im Hinblick auf die geschaffenen Potenziale von Praktikern bewertet sowie einer kritischen Reflexion unterzogen. Abschließend werden Potenziale für die weitere Forschung vorgestellt