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51.
To investigate the effect of leptin in childhood ITP, we measured plasma leptin in 39 children with acute ITP, after treatment and in remission, and in 33 healthy age/BMI-matched controls. We also cultured ITP and control peripheral blood mononuclear cells (PBMCs) with recombinant leptin to assess its direct effect on pro/anti-inflammatory cytokine gene expression. A significant increase in leptin was observed in children with active disease compared to controls. A significant inverse correlation of leptin with platelet count was also observed in children with acute ITP. Leptin remained high after treatment with IVIg, whereas steroid treatment lowered leptin below control levels. In remission, leptin was in the control range. Cytokine gene expression was significantly increased in children with acute ITP compared with controls, with highest expression for IFN-γ and IL-10. IVIg/steroid treatment significantly decreased IFN-γ and IL-10 expression. In remission, IFN-γ and IL-10 expression remained low. Addition of leptin to PBMCs isolated from patients in remission resulted in a significant increase in IL-10 gene expression compared to controls. Further experiments with purified T-cells and monocytes identified monocytes as the source of leptin-induced IL-10. We suggest that leptin acts as an active anti-inflammatory agent in childhood ITP by promoting IL-10 secretion by monocytes.  相似文献   
52.
Piezo1/2 are mechanosensitive calcium-permeable channels that can be activated by various modes of membrane deformation. The identification of the small molecule Yoda1, a synthetic Piezo1 agonist, revealed the possibility of chemical activation of the channel. Stimulating effects of Yoda1 on Piezo1 have been mainly documented using over-expressing cellular systems or channel proteins incorporated in artificial lipid bilayers. However, the activating effect of Yoda1 on native Piezo1 channels in the plasma membrane of living cells remains generally undefined, despite the increasing number of studies in which the agonist is utilized as a functional tool to reveal the contribution of Piezo1 to cellular reactions. In the current study, we used the human myeloid leukemia K562 cell line as a suitable model to examine chemically induced Piezo1 activity with the use of the patch-clamp technique in various specific modes. The functional expression of Piezo1 in leukemia cells was evidenced using a combinative approach, including single channel patch-clamp measurements. Utilizing our established single-current whole-cell assay on K562 cells, we have shown, for the first time, the selective real-time chemical activation of endogenously expressed Piezo1. Extracellular application of 0.5–1 µM Yoda1 effectively stimulated single Piezo1 currents in the cell membrane.  相似文献   
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This research reviews challenges in building sustainable relationships between the parties involved in the crowdfunding and crowdsourcing projects, which are running in extreme situations, such as the COVID-19 pandemic. This study aims to solve problems that generate the crowdsourcing concerns and to find better alternatives to increase trust for crowdfunding among donors, as this impacts their strategic sustainability in the conditions of turbulence and COVID-induced financial crisis. It was found that factors influence donor decisions in different ways, yet the common tendency for donor activity is non-monotonicity. Future development in the field of sustainable relationships should focus on creating a donor classification system.

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55.
Biodegradable implants are required in order to provide successful treatment of injuries. Temporary magnesium‐based implants with particular properties are needed in cases when it is desirable not only to maintain vital activity, but also to initiate the self‐healing process of damaged bones or tissues as well. Unfortunately, the use of magnesium alloys is limited due to the fast biodegradability of the applied material. The aim of this research is to improve the corrosion resistance of magnesium alloys by sonochemical treatment in silk solution followed by additional layer‐by‐layer deposition of natural silk on the magnesium surface. The sonication process is carried out at a frequency of 20 kHz during 5–10 min, while the duration of the silk layer deposition is 15 min. The corrosion behavior of magnesium substrates modified by natural silk layer‐by‐layer assembly is studied. Magnesium substrates sonochemically treated in silk solution demonstrate three times better corrosion resistance compared to control samples sonochemically treated in water. Additional deposition of a silk layer enhances obtained corrosion resistance by 18 times, resulting in a 54‐fold increase overall.  相似文献   
56.
Territorial Impact Assessment (TIA) is proposed as a critical tool in order to investigate the way policies affect spatial development and hence territorial cohesion. The paper introduces a TIA methodological model in relation to transport sector. The design of the methodological model is based on a quantitative evaluation framework that comprises a set of selected indicators applied in a cross-border area of southeast Europe, influenced by the operation of the Greek motorway system of Egnatia and its vertical axes. The indicators are grouped into three main fields of TIA, i.e. transport intermodality, polycentric spatial organization and cross-border territorial cooperation. The TIA’s indicators are approximated by quantitative analysis. The procedure concludes to an overall composite indicator measuring the ‘level of territorial cohesion’ along with some core results and the expected added value. It also highlights some key technical aspects about the routines used and proceeds to suggestions for further refinement.  相似文献   
57.

The article substantiates that the transformation of the world economy associated with Industry 4.0 leads to a significant change in the way resources are used and affects the possibility of implementing the concept of sustainable development. In this regard, a combined analysis of the concept of new industrial development and the concept of sustainable development, as well as an assessment of the current practice of their implementation is required. In this paper, such an analysis was carried out on the example of water resources management. The paper proposes a methodology for assessing the correlation of water management and industrial development levels of regions. This includes the use of both traditional statistical approaches to the analysis of the level of development of economic systems, and elements of data mining. The neural network is constructed in order to estimate the forecasted values of the water intensity of the gross regional product when the indicators of the level of industrial development of the regions change. The results show that the most significant indicators for changing water intensity include advanced production technologies used, the share of value-added to high-tech industries, and innovative activities of organisations.

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58.
In this study, the effect of co-fermentation and sequential fermentation with a typical halophilic soy sauce yeast Candida versatilis and a non-halophilic dairy bacterium Lactococcus lactis subsp. cremoris in pork hydrolysates was explored for the first time with regard to their viability, physicochemical changes and volatile compound production. It was observed that the growth of C. versatilis was suppressed (only 0.6 - 1.5 log CFU mL−1 increase), whilst L. lactis subsp. cremoris was stimulated (total cell counts exceeded 9.0 log CFU mL−1) in mixed-cultures relative to the respective monocultures. There were no significant differences between co-inoculation and sequential inoculation regarding glucose consumption, organic acid production and free amino acids utilisation. Some distinct volatile compounds such as methionol, 6-methyl-5-hepten-2-one and gamma-nonalactone were found in both co-inoculated and sequentially inoculated samples, with slightly different concentrations. These results suggest that the mixed-inoculation of C. versatilis and L. lactis have a positive impact on the volatile compounds formation in pork hydrolysates.  相似文献   
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The Journal of Supercomputing - The parallel efficiency is raised by increasing the locality of calculation. With the locally recursive non-locally asynchronous algorithms method, we have...  相似文献   
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