Smart Wireless Communication Platform IQRF

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New Role for L-Arginine in Regulation of Inducible Nitric-Oxide-Synthase-Derived Superoxide Anion Production in Raw 264.7 Macrophages

Dietary supplementation with L-arginine was shown to improve immune responses in various inflammatory models. However, the molecular mechanisms underlying L-arginine effects on immune cells remain unrecognized. Herein, we tested the hypothesis that a limitation of L-arginine could lead to the uncoupled state of murine macrophage inducible nitric oxide synthase and, therefore, increase inducible nitric-oxide-synthase-derived superoxide anion formation. Importantly, we demonstrated that L-arginine dose- and time dependently potentiated superoxide anion production in bacterial endotoxin-stimulated macrophages, although it did not influence NADPH oxidase expression and activity. Detailed analysis of macrophage activation showed the time dependence between LPS-induced iNOS expression and increased O2∙− formation. Moreover, downregulation of macrophage iNOS expression, as well as the inhibition of iNOS activity by NOS inhibitors, unveiled an important role of this enzyme in controlling O2∙− and peroxynitrite formation during macrophage stimulation. In conclusion, our data demonstrated that simultaneous induction of NADPH oxidase, together with the iNOS enzyme, can result in the uncoupled state of iNOS resulting in the production of functionally important levels of O2∙− soon after macrophage activation with LPS. Moreover, we demonstrated, for the first time that increased concentrations of L-arginine further potentiate iNOS-dependent O2∙− formation in inflammatory macrophages

Design of pressure sensor based on optical fiber Bragg grating lateral deformation

This paper describes steps involved in the design and realization of a new type of pressure sensor based on the optical fiber Bragg grating. A traditional pressure sensor has very limited usage in heavy industrial environments, explosive or electromagnetically noised environments in particular. Utilization of optics in these environments eliminates all surrounding influences. An initial motivation for our development was research, experimental validation, and realization of a complex smart pressure sensor based on the optical principle. The main benefit of this solution consists of increasing sensitivity, resistance to electromagnetic interference, dimensions, and potential accuracy.This paper describes steps involved in the design and realization of a new type of pressure sensor based on the optical fiber Bragg grating. A traditional pressure sensor has very limited usage in heavy industrial environments, explosive or electromagnetically noised environments in particular. Utilization of optics in these environments eliminates all surrounding influences. An initial motivation for our development was research, experimental validation, and realization of a complex smart pressure sensor based on the optical principle. The main benefit of this solution consists of increasing sensitivity, resistance to electromagnetic interference, dimensions, and potential accuracy

Smart City Concept, aplikace a služby

The purpose of this article is to summarize the current state of understanding the smart city concept and to present a proposed communication platform for the development of city services.Účelem tohoto článku je shrnout současný stav poznání města koncept inteligentní a prezentovat navrhované komunikační platformu pro rozvoj městských služeb

Asymmetric dimethyl arginine induces pulmonary vascular dysfunction via activation of signal transducer and activator of transcription 3 and stabilization of hypoxia-inducible factor 1-alpha

Pulmonary hypertension (PH), associated with imbalance in vasoactive mediators and massive remodeling of pulmonary vasculature, represents a serious health complication. Despite the progress in treatment, PH patients typically have poor prognoses with severely affected quality of life. Asymmetric dimethyl arginine (ADMA), endogenous inhibitor of endothelial nitric oxide synthase (eNOS), also represents one of the critical regulators of pulmonary vascular functions. The present study describes a novel mechanism of ADMA-induced dysfunction in human pulmonary endothelial and smooth muscle cells. The effect of ADMA was compared with well-established model of hypoxia-induced pulmonary vascular dysfunction. It was discovered for the first time that ADMA induced the activation of signal transducer and activator of transcription 3 (STAT3) and stabilization of hypoxia inducible factor la (HIF-1 alpha) in both types of cells, associated with drastic alternations in normal cellular functions (e.g., nitric oxide production, cell proliferation/Ca2+ concentration, production of pro-inflammatory mediators, and expression of eNOS, DDAH1, and ICAM-1). Additionally, ADMA significantly enhanced the hypoxia-mediated increase in the signaling cascades. In summary, increased ADMA may lead to manifestation of PH phenotype in human endothelial and smooth muscle cells via the STAT3/HIF-1 alpha cascade. Therefore this signaling pathway represents the potential pathway for future clinical interventions in PH. (C) 2015 Elsevier Inc. All rights reserved

Nitro-Oleic Acid Prevents Hypoxia- and Asymmetric Dimethylarginine-Induced Pulmonary Endothelial Dysfunction

Pulmonary hypertension (PH) represents a serious health complication accompanied with hypoxic conditions, elevated levels of asymmetric dimethylarginine (ADMA), and overall dysfunction of pulmonary vascular endothelium. Since the prevention strategies for treatment of PH remain largely unknown, our study aimed to explore the effect of nitro-oleic acid (OA-NO2), an exemplary nitro-fatty acid (NO2-FA), in human pulmonary artery endothelial cells (HPAEC) under the influence of hypoxia or ADMA. HPAEC were treated with OA-NO2 in the absence or presence of hypoxia and ADMA. The production of nitric oxide (NO) and interleukin-6 (IL-6) was monitored using the Griess method and ELISA, respectively. The expression or activation of different proteins (signal transducer and activator of transcription 3, STAT3; hypoxia inducible factor 1 alpha, HIF-1 alpha; endothelial nitric oxide synthase, eNOS; intercellular adhesion molecule-1, ICAM-1) was assessed by the Western blot technique. We discovered that OA-NO2 prevents development of endothelial dysfunction induced by either hypoxia or ADMA. OA-NO2 preserves normal cellular functions in HPAEC by increasing NO production and eNOS expression. Additionally, OA-NO2 inhibits IL-6 production as well as ICAM-1 expression, elevated by hypoxia and ADMA. Importantly, the effect of OA-NO2 is accompanied by prevention of STAT3 activation and HIF-1 alpha stabilization. In summary, OA-NO2 eliminates the manifestation of hypoxia- and ADMA-mediated endothelial dysfunction in HPAEC via the STAT3/HIF-1 alpha cascade. Importantly, our study is bringing a new perspective on molecular mechanisms of NO2-FAs action in pulmonary endothelial dysfunction, which represents a causal link in progression of PH