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81.
Paulina Nuez Bernal Paul Delrot Damien Loterie Yang Li Jos Malda Christophe Moser Riccardo Levato 《Advanced materials (Deerfield Beach, Fla.)》2019,31(42)
Biofabrication technologies, including stereolithography and extrusion‐based printing, are revolutionizing the creation of complex engineered tissues. The current paradigm in bioprinting relies on the additive layer‐by‐layer deposition and assembly of repetitive building blocks, typically cell‐laden hydrogel fibers or voxels, single cells, or cellular aggregates. The scalability of these additive manufacturing technologies is limited by their printing velocity, as lengthy biofabrication processes impair cell functionality. Overcoming such limitations, the volumetric bioprinting of clinically relevant sized, anatomically shaped constructs, in a time frame ranging from seconds to tens of seconds is described. An optical‐tomography‐inspired printing approach, based on visible light projection, is developed to generate cell‐laden tissue constructs with high viability (>85%) from gelatin‐based photoresponsive hydrogels. Free‐form architectures, difficult to reproduce with conventional printing, are obtained, including anatomically correct trabecular bone models with embedded angiogenic sprouts and meniscal grafts. The latter undergoes maturation in vitro as the bioprinted chondroprogenitor cells synthesize neo‐fibrocartilage matrix. Moreover, free‐floating structures are generated, as demonstrated by printing functional hydrogel‐based ball‐and‐cage fluidic valves. Volumetric bioprinting permits the creation of geometrically complex, centimeter‐scale constructs at an unprecedented printing velocity, opening new avenues for upscaling the production of hydrogel‐based constructs and for their application in tissue engineering, regenerative medicine, and soft robotics. 相似文献
82.
Katarzyna Kurianowicz Maria Klatka Agnieszka Polak Anna Hymos Dominika Bbnowska Martyna Podgajna Rafa Hrynkiewicz Olga Sierawska Paulina Nied
wiedzka-Rystwej 《International journal of molecular sciences》2021,22(22)
Type 1 diabetes (DM1) is classified as an autoimmune disease. An uncontrolled response of B and T lymphocytes to the body’s own tissues develops in the absence of immune tolerance. The main aim of the study was to evaluate the effect of the duration of type 1 diabetes in children on the expression of TLR receptors and the relationship with the parameters of glycemic control in patients. As a result, we showed significant differences in the level of TLR2, TLR4 and TLR9 expression in patients with DM1 in the early stage of the disease and treated chronically compared to the healthy group. Additionally, in this study, we found that the numbers of CD19+ B cells, CD3+ CD4+, CD3+ CD8+ T cells and NK cells are different for newly diagnosed DM1 individuals, patients receiving chronic treatment and for healthy controls, indicating an important role of these cells in killing pancreatic beta cells. Moreover, higher levels of IL-10 in patients with newly diagnosed DM1 have also been found, confirming the reports found in the literature. 相似文献
83.
Monika Zaborek-yczba Jakub yczba Paulina Mertowska Sebastian Mertowski Anna Hymos Martyna Podgajna Paulina Nied
wiedzka-Rystwej Ewelina Grywalska 《International journal of molecular sciences》2021,22(24)
The human G-leukocyte antigen (HLA-G) molecule is a non-classical major histocompatibility complex (MHC) class I molecule. The pertinence of HLA-G has been investigated in numerous studies which have sought to elucidate the relevance of HLA-G in pathologic conditions, such as autoimmune diseases, cancers, and hematologic malignancies. One of the main goals of the current research on HLA-G is to use this molecule in clinical practice, either in diagnostics or as a therapeutic target. Since HLA-G antigens are currently considered as immunomodulatory molecules that are involved in reducing inflammatory and immune responses, in this review, we decided to focus on this group of antigens as potential determinants of progression in autoimmune diseases. This article highlights what we consider as recent pivotal findings on the immunomodulatory function of HLA-G, not only to establish the role of HLA-G in the human body, but also to explain how these proteins mediate the immune response. 相似文献
84.
Magorzata Krzystek-Korpacka Mariusz G. Fleszar Paulina Fortuna Kinga Gostomska-Pampuch ukasz Lewandowski Tomasz Piasecki Bogna Kosyk Adam Szelg Magorzata Trocha 《International journal of molecular sciences》2021,22(23)
Molecular mechanisms underlying the beneficial effect of sitagliptin repurposed for hepatic ischemia-reperfusion injury (IRI) are poorly understood. We aimed to evaluate the impact of IRI and sitagliptin on the hepatic profile of eicosanoids (LC-MS/MS) and expression/concentration (RTqPCR/ELISA) of GLP-1/GLP-1R, SDF-1α/CXCR4 and VIP/VPAC1, VPAC2, and PAC1 in 36 rats. Animals were divided into four groups and subjected to ischemia (60 min) and reperfusion (24 h) with or without pretreatment with sitagliptin (5 mg/kg) (IR and SIR) or sham-operated with or without sitagliptin pretreatment (controls and sitagliptin). PGI2, PGE2, and 13,14-dihydro-PGE1 were significantly upregulated in IR but not SIR, while sitagliptin upregulated PGD2 and 15-deoxy-12,14-PGJ2. IR and sitagliptin non-significantly upregulated GLP-1 while Glp1r expression was borderline detectable. VIP concentration and Vpac2 expression were downregulated in IR but not SIR, while Vpac1 was significantly downregulated solely in SIR. IRI upregulated both CXCR4 expression and concentration, and sitagliptin pretreatment abrogated receptor overexpression and downregulated Sdf1. In conclusion, hepatic IRI is accompanied by an elevation in proinflammatory prostanoids and overexpression of CXCR4, combined with downregulation of VIP/VPAC2. Beneficial effects of sitagliptin during hepatic IRI might be mediated by drug-induced normalization of proinflammatory prostanoids and upregulation of PGD2 and by concomitant downregulation of SDF-1α/CXCR4 and reinstating VIP/VCAP2 signaling. 相似文献
85.
Paulina Grska Adriana Zaleska Ewa Kowalska Tomasz Klimczuk Janusz W. Sobczak Ewa Skwarek Wadysaw Janusz Jan Hupka 《Applied catalysis. B, Environmental》2008,84(3-4):440-447
A series of TiO2 photocatalysts were obtained using several calcination temperatures ranging from 350 to 750 °C. The photocatalysts’ characteristics by X-ray diffraction, UV–vis and FTIR diffuse reflectance spectroscopies, X-ray photoelectron spectroscopy, BET and BJH methods showed that sample active in vis region had anatase structure, about 200 m2/g specific surface area, absorbed light for λ > 400 nm and contained 10.1 at.% of C–C species. The photocatalytic activity of the catalysts was estimated by measuring the decomposition rate of phenol in 0.21 mM aqueous solution in visible and ultraviolet light. The experimental data clearly indicate correlation between the absorption intensity of irradiation by obtained powders and their photocatalytic performance in phenol degradation. An increase in absorbance over the entire vis region and the highest photocatalytic activity for phenol degradation in visible light (λ > 400 nm) occurred for photocatalyst calcinated at 350 °C. Photocatalyst processed at 450 °C had the best activity in UV light (250 < λ < 400 nm). 相似文献
86.
Dagmara Mierzejewska Paulina Mitrowska Bogumila Rudnicka Ewa Kubicka Henryk Kostyra 《Food chemistry》2008
The aim of this study was to determine the effect of non-enzymatic glycosylation of pea proteins on their immunoreactive properties. Extracted total pea albumins were glycated. No changes were found in molecular weight distribution of total pea albumins before and after glycation using size exclusion chromatography and SDS–PAGE methods. SDS–PAGE GLYCO test stained the glycated proteins and OPA method showed 15% progress in glycation. Glycated and unglycated pea albumins were orally and intraperitoneally administered to Balb/C mice. Serum specific IgG and IgA and sIgA were determined. No difference in serum specific IgG level was found after oral mice immunization with TA and GTA. In the presence of antigen SPL lymphocytes culture showed higher proliferation activity as compared to the culture without the antigen addition. The glycation does not change the immunoreactivity of proteins significantly. During the presented route of immunization with TA and GTA specific tolerance mechanism could be induced. 相似文献
87.
Paulina de la Mata-Espinosa Juan Manuel Bosque-Sendra Luis Cuadros-Rodr��guez 《Food Analytical Methods》2011,4(4):574-581
This paper describes a reversed phase high-performance liquid chromatography method for the quantification of triacylglycerol
(TAG) compositional profile in olive oils. The chromatographic separation was achieved using a C18 column, and the detection
was accomplished using a charged aerosol detector. TAG peaks were identified using retention times and by addition of TAG
standards. The linearity, matrix effect, and accuracy (precision and trueness) were validated; detection and quantification
limits of the method were estimated. The developed analytical method was applied to the determination of the TAG composition
and the estimation of the concentration of each individual TAG, using an internal quantification standard (tristearin). From
the TAG compositional profile, a fatty acid compositional profile could be calculated. The proposed method appears to be rapid
and simple to determine TAGs in olive oil. 相似文献
88.
Myroslav Sprynskyy Paulina Szczyglewska Izabela Wojtczak Izabela Nowak Andrzej Witkowski Bogusaw Buszewski Agnieszka Feliczak-Guzik 《International journal of molecular sciences》2021,22(13)
A new catalyst based on biosilica doped with palladium(II) chloride nanoparticles was prepared and tested for efficient degradation of methyl orange (MO) in water solution under UV light excitation. The obtained photocatalyst was characterized by X-ray diffraction, TEM and N2 adsorption/desorption isotherms. The photocatalytic degradation process was studied as a function of pH of the solution, temperature, UV irradiation time, and MO initial concentration. The possibilities of recycling and durability of the prepared photocatalysts were also tested. Products of photocatalytic degradation were identified by liquid chromatography–mass spectrometry analyses. The photocatalyst exhibited excellent photodegradation activity toward MO degradation under UV light irradiation. Rapid photocatalytic degradation was found to take place within one minute with an efficiency of 85% reaching over 98% after 75 min. The proposed mechanism of photodegradation is based on the assumption that both HO• and O2•− radicals, as strongly oxidizing species that can participate in the dye degradation reaction, are generated by the attacks of photons emitted from diatom biosilica (photonic scattering effect) under the influence of UV light excitation. The degradation efficiency significantly increases as the intensity of photons emitted from biosilica is enhanced by palladium(II) chloride nanoparticles immobilized on biosilica (synergetic photonic scattering effect). 相似文献
89.
Paulina Borkowska Aleksandra Zielinska Monika Paul-Samojedny Rafa Stojko Jan Kowalski 《International journal of molecular sciences》2021,22(13)
Mesenchymal stem cells (MSC) are potentially a good material for transplantation in many diseases, including neurodegenerative diseases. The main problem with using them is the low percentage of surviving cells after the transplant procedure and the naturally poor ability of MSC to spontaneously differentiate into certain types of cells, which results in their poor integration with the host cells. The aim and the novelty of this work consists in the synergistic overexpression of two genes, BCL2 and BDNF, using lentiviral vectors. According to our hypothesis, the overexpression of the BCL2 gene is aimed at increasing the resistance of cells to stressors and toxic factors. In turn, the overexpression of the BDNF gene is suspected to direct the MSC into the neural differentiation pathway. As a result, it was shown that the overexpression of both genes and the overproduction of proteins is permanent and persists for at least 60 days. The synergistically transduced MSC were significantly more resistant to the action of staurosporine; 12 days after transduction, the synergistically transduced MSC had a six-times greater survival rate. The overexpression of the Bcl-2 and BDNF proteins was sufficient to stimulate a significant overexpression of the CHAT gene, and under specific conditions, the TH, TPH1, and SYP genes were also overexpressed. Modified MSC are able to differentiate into cholinergic and dopaminergic neurons, and the release of acetylcholine and dopamine may indicate their functionality. 相似文献
90.
Ordered mesoporous tin oxide and tin phosphate were successfully synthesized via two-step nanocasting route. The SBA-15 silica
and CMK-3 carbon were used as hard templates. Powder X-ray diffraction, nitrogen adsorption and transmission electron microscopy
confirmed hexagonal mesoporous structure of resulted products. Mesoporous tin oxide indicated crystalline walls (cassiterite).
The mesoporous products showed considerable catalytic activity in propan-2-ol decomposition. The tin oxide led the dehydrogenation
towards acetone, while mesoporous tin phosphate exhibited activity of acid sites resulting in dehydration to propene. 相似文献