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Plastic pollution is one of the crucial global challenges nowadays, and biodegradation is a promising approach to manage plastic waste in an environment-friendly and cost-effective way. In this study we identified the strain of fungus Trichoderma viride GZ1, which was characterized by particularly high pectinolytic activity. Using differential scanning calorimetry, Fourier-transform infrared spectroscopy techniques, and viscosity measurements we showed that three-month incubation of polylactide and polyethylene terephthalate in the presence of the fungus lead to significant changes of the surface of polylactide. Further, to gain insight into molecular mechanisms underneath the biodegradation process, western blot hybridization was used to show that in the presence of poly(ethylene terephthalate) (PET) in laboratory conditions the fungus produced hydrophobin proteins. The mycelium adhered to the plastic surface, which was confirmed by scanning electron microscopy, possibly due to the presence of hydrophobins. Further, using atomic force microscopy we demonstrated for the first time the formation of hydrophobin film on the surface of aliphatic polylactide (PLA) and PET by T. viride GZ1. This is the first stage of research that will be continued under environmental conditions, potentially leading to a practical application.  相似文献   
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Motile cilia and homologous organelles, the flagella, are an early evolutionarily invention, enabling primitive eukaryotic cells to survive and reproduce. In animals, cilia have undergone functional and structural speciation giving raise to typical motile cilia, motile nodal cilia, and sensory immotile cilia. In contrast to other cilia types, typical motile cilia are able to beat in complex, two-phase movements. Moreover, they contain many additional structures, including central apparatus, composed of two single microtubules connected by a bridge-like structure and assembling numerous complexes called projections. A growing body of evidence supports the important role of the central apparatus in the generation and regulation of the motile cilia movement. Here we review data concerning the central apparatus structure, protein composition, and the significance of its components in ciliary beating regulation.  相似文献   
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Iron deficiency is the most common mammalian nutritional disorder. However, among mammalian species iron deficiency anemia (IDA), occurs regularly only in pigs. To cure IDA, piglets are routinely injected with high amounts of iron dextran (FeDex), which can lead to perturbations in iron homeostasis. Here, we evaluate the therapeutic efficacy of non-invasive supplementation with Sucrosomial iron (SI), a highly bioavailable iron supplement preventing IDA in humans and mice and various iron oxide nanoparticles (IONPs). Analysis of red blood cell indices and plasma iron parameters shows that not all iron preparations used in the study efficiently counteracted IDA comparable to FeDex-based supplementation. We found no signs of iron toxicity of any tested iron compounds, as evaluated based on the measurement of several toxicological markers that could indicate the occurrence of oxidative stress or inflammation. Neither SI nor IONPs increased hepcidin expression with alterations in ferroportin (FPN) protein level. Finally, the analysis of the piglet gut microbiota indicates the individual pattern of bacterial diversity across taxonomic levels, independent of the type of supplementation. In light of our results, SI but not IONPs used in the experiment emerges as a promising nutritional iron supplement, with a high potential to correct IDA in piglets.  相似文献   
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The present paper discloses a new alternative method for the isomerization of eugenol to isoeugenol where mesoporous materials containing niobium are used as solid base catalysts, affording good yields of isomerized product and being environmentally friendly. Nb-containing MCM-41 mesoporous materials were modified with alkaline cations (Li, Na, K, Rb and Cs) and characterized by BET, FTIR, XRD, and UV–vis techniques. The prepared materials were tested in the isomerization of eugenol to isoeugenol by sonochemical and thermally-activated reactions. Li, Na, K, Rb, and Cs/NbMCM-41 catalysts are active catalyst for the preparation of isoeugenol, and selective to the trans-isomer. Rb/NbMCM-41 sample is the optimum catalysts for the reaction. This result is in accordance with the calculated basicity observed during the Knoevenagel probe reaction of basicity. Conversions around 90% are obtained when using Rb-NbMCM-41 catalysts, with 90% selectivity to trans-isoeugenol, under ultrasound activation. In contrast, conversion around 72% with 90% selectivity is attained under classical thermal activation. The catalysts were reused four times without a substantial decrease of activity.  相似文献   
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TNF-related apoptosis-inducing ligand (TRAIL) is a type II transmembrane protein capable of selectively inducing apoptosis in cancer cells by binding to its cognate receptors. Here, we examined the anticancer efficacy of a recently developed chimeric AD-O51.4 protein, a TRAIL fused to the VEGFA-originating peptide. We tested AD-O51.4 protein activity against human colorectal cancer (CRC) models and investigated the resistance mechanism in the non-responsive CRC models. The quantitative comparison of apoptotic activity between AD-O51.4 and the native TRAIL in nine human colorectal cancer cell lines revealed dose-dependent toxicity in seven of them; the immunofluorescence-captured receptor abundance correlated with the extent of apoptosis. AD-O51.4 reduced the growth of CRC patient-derived xenografts (PDXs) with good efficacy. Cell lines that acquired AD-O51.4 resistance showed a significant decrease in surface TRAIL receptor expression and apoptosis-related proteins, including Caspase-8, HSP60, and p53. These results demonstrate the effectiveness of AD-O51.4 protein in CRC preclinical models and identify the potential mechanism underlying acquired resistance. Progression of AD-O51.4 to clinical trials is expected.  相似文献   
28.
Extracellular vesicles (EVs) have been identified as key messengers of intracellular communication in health and disease, including the lung. EVs that can be found in bronchoalveolar lavage fluid (BALF) are released by multiple cells of the airways including bronchial epithelial cells, endothelial cells, alveolar macrophages, and other immune cells, and they have been shown to mediate proinflammatory signals in many inflammatory lung diseases. They transfer complex molecular cargo, including proteins, cytokines, lipids, and nucleic acids such as microRNA, between structural cells such as pulmonary epithelial cells and innate immune cells such as alveolar macrophages, shaping mutually their functions and affecting the alveolar microenvironment homeostasis. Here, we discuss this distinct molecular cargo of BALF-EVs in the context of inducing and propagating inflammatory responses in particular acute and chronic lung disorders. We present different identified cellular interactions in the inflammatory lung via EVs and their role in lung pathogenesis. We also summarize the latest studies on the potential use of BALF-EVs as diagnostic and prognostic biomarkers of lung diseases, especially of lung cancer.  相似文献   
29.
The article presents results of the research on the influence of graphite/kaolin and graphite/titanium oxide systems on thermal properties, intumescence degree and the integrity of the structure of intumescent protective films based on epoxy resins for steel. The TG/DTG/DSC analysis showed that graphite/kaolin system shifted the decomposition reaction of epoxy resin towards higher temperatures, even by about 30°C. Fire endurance tests and the SEM analysis confirmed these results because more thermally resistant (T500°C reached after 37.5 min for 1.1 coating thickness), swollen (about 20 times) and homogeneous coatings were obtained. The presented results suggest that ceramic fire retardants can successfully cooperate with organic components in intumescent protective coatings for steel elements.  相似文献   
30.
The structural quality of GaN overgrown layers was evaluated using Transmission Electron Microscopy methods. Growth on polar and non-polar substrates was compared. Independent from growth polarity much better structural quality of the overgrown areas compared to the seed areas was obtained, but overgrowth on non-polar substrates is more difficult. For the latest samples, two wings on the opposite sites of the seed area grow in two different polar directions with different growth rates. Wings grown with Ga polarity are much wider than wings grown with N-polarity making coalescence of these layers difficult. Defects formed in the overgrown wings were characterized and their density was compared. It is shown that two-step growth (using two different temperatures) lead to much smaller misorientation between the wings than one step growth  相似文献   
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