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61.
Hypoxia is an integral component of the tumor microenvironment. Either as chronic or cycling hypoxia, it exerts a similar effect on cancer processes by activating hypoxia-inducible factor-1 (HIF-1) and nuclear factor (NF-κB), with cycling hypoxia showing a stronger proinflammatory influence. One of the systems affected by hypoxia is the CXC chemokine system. This paper reviews all available information on hypoxia-induced changes in the expression of all CXC chemokines (CXCL1, CXCL2, CXCL3, CXCL4, CXCL5, CXCL6, CXCL7, CXCL8 (IL-8), CXCL9, CXCL10, CXCL11, CXCL12 (SDF-1), CXCL13, CXCL14, CXCL15, CXCL16, CXCL17) as well as CXC chemokine receptors—CXCR1, CXCR2, CXCR3, CXCR4, CXCR5, CXCR6, CXCR7 and CXCR8. First, we present basic information on the effect of these chemoattractant cytokines on cancer processes. We then discuss the effect of hypoxia-induced changes on CXC chemokine expression on the angiogenesis, lymphangiogenesis and recruitment of various cells to the tumor niche, including myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), tumor-associated neutrophils (TANs), regulatory T cells (Tregs) and tumor-infiltrating lymphocytes (TILs). Finally, the review summarizes data on the use of drugs targeting the CXC chemokine system in cancer therapies.  相似文献   
62.
Antimicrobial peptides (AMPs) constitute a promising tool in the development of novel therapeutic agents useful in a wide range of bacterial and fungal infections. Among the modifications improving pharmacokinetic and pharmacodynamic characteristics of natural AMPs, an important role is played by lipidation. This study focuses on the newly designed and synthesized lipopeptides containing multiple Lys residues or their shorter homologues with palmitic acid (C16) attached to the side chain of a residue located in the center of the peptide sequence. The approach resulted in the development of lipopeptides representing a model of surfactants with two polar headgroups. The aim of this study is to explain how variations in the length of the peptide chain or the hydrocarbon side chain of an amino acid residue modified with C16, affect biological functions of lipopeptides, their self-assembling propensity, and their mode of action.  相似文献   
63.
Journal of Real-Time Image Processing - In this paper, a novel approach to the problem of impulsive noise removal in color digital images is presented. The described switching filter is based on...  相似文献   
64.
The aim of this research was to observe the relationship between zeta potential, morphology, surface area, porosity, chemical composition, and ecotoxicity of nanocomposite powders such as Au/TiO2, Ag2O/TiO2, PdO/TiO2, Ag/TiO2/SiO2, Ag/N(C)TiO2, and SiO2/TiO2 from which Ag2O/TiO2, Ag/N(C)/TiO2, and Ag/TiO2/SiO2 were exhibiting good antimicrobial properties. It was observed, that nanomaterials characterized by similar morphology and zeta potential revealed the similar toxic behavior. The samples of higher agglomeration and higher zeta potential, especially Ag/TiO2/SiO2 xerogel and TiO2/SiO2 aerogel were generally less ecotoxic to water organisms and plants. They were also not genotoxic in concentrations up to 500 and 250 mg/L, respectively.  相似文献   
65.
A frequency-division multiplexed optical fiber link is described in which microwave (1-8 GHz) and baseband digital (1-10 Mb/s) signals are combined electrically and transmitted through a direct-modulation microwave optical link. The microwave signal does not affect bit error rate (BER) performance of the Manchester-coded baseband digital data link. The baseband digital signal affects microwave signal quality by generating second-order intermodulation noise. The intermodulation noise power density is found to be proportional to both the microwave input power and the digital input power, enabling the system to be modeled as a mixer (AM modulator). The conversion loss for the digital signal is approximately 68 dB for a 1-GHz microwave signal and is highly dependent on the microwave frequency, reaching a minimum value of 41 dB at 4.5 GHz corresponding to the laser diode relaxation oscillation frequency. It is shown that Manchester coding on the digital link places the intermodulation noise peak away from microwave signal, preventing degradation of close-carrier phase noise (<1 kHz offset). A direct trade-off between intermodulation noise and digital link margin is developed to project system performance  相似文献   
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In the paper, maximum principle for a two-directionally continuous variant of a linear autonomous repetitive process with cost functional depending on a fixed “end-function” is obtained. Maximum condition has a pointwise form, a conjugate system has a Fornasini-Marchesini form. The result is derived from the extremum principle for smooth-convex problems, due to Ioffe and Tikhomirov.  相似文献   
68.
The aim of this article is the study of the potential relationships between PAHs contamination, physicochemical parameters, and microbial activity in industrial soils. The research was based on two series of measurements. The first was conducted in June 2013 and the second in November 2013. Samples used in study were collected from the area of fuel handling and a loading station, located in the Silesia region of Poland. All collected samples were characterized by the following analytical procedures: PAHs content analysis, the basic physical and chemical parameters determinations (pH, CEC, humic acids content, TC, TN, TP) and microbial activity analysis. The obtained results were also subjected to statistical analysis, based on the Pearson's correlation coefficient calculations.

Results collected during described above procedure show that: the PAHs content was highly positively correlated with C and N contents (p < 0.001) and moderately correlated with humic acids and P contents (p < 0.01). This phenomenon confirms the thesis that the increase of soil organic matter content promotes accumulation of hydrophobic organic compounds such as PAHs. Microbiological analysis shows that bacteria from the mesophilic group are most resistant to PAHs contamination. This information indicates that the organisms belonging to this group should be considered as potentially useful in the soil bioremediation processes.  相似文献   

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A thermodynamic criterion for selection of a fluid both for subcritical and supercritical organic Rankine cycle has been proposed. Theoretical performances of few fluids have been comparatively assessed for use in low-temperature domestic organic Rankine cycle micro systems. Of the 20 fluids investigated, ethanol, R123 and R141b appear as the most suitable for small scale domestic CHP applications.  相似文献   
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