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排序方式: 共有375条查询结果,搜索用时 15 毫秒
81.
Patrycja Koszalka Barbara Kutryb-Zajac Paulina Mierzejewska Marta Tomczyk Joanna Wietrzyk Pawel K. Serafin Ryszard T. Smolenski Ewa M. Slominska 《International journal of molecular sciences》2022,23(10)
The accumulation of specific metabolic intermediates is known to promote cancer progression. We analyzed the role of 4-pyridone-3-carboxamide-1-β-D-ribonucleoside (4PYR), a nucleotide metabolite that accumulates in the blood of cancer patients, using the 4T1 murine in vivo breast cancer model, and cultured cancer (4T1) and endothelial cells (ECs) for in vitro studies. In vivo studies demonstrated that 4PYR facilitated lung metastasis without affecting primary tumor growth. In vitro studies demonstrated that 4PYR affected extracellular adenine nucleotide metabolism and the intracellular energy status in ECs, shifting catabolite patterns toward the accumulation of extracellular inosine, and leading to the increased permeability of lung ECs. These changes prevailed over the direct effect of 4PYR on 4T1 cells that reduced their invasive potential through 4PYR-induced modulation of the CD73-adenosine axis. We conclude that 4PYR is an oncometabolite that affects later stages of the metastatic cascade by acting specifically through the regulation of EC permeability and metabolic controls of inflammation. 相似文献
82.
Paulina Stolarek Przemysaw Bernat Antoni Ralski 《International journal of molecular sciences》2022,23(21)
Proteus mirabilis is a common cause of catheter-associated urinary tract infections (CAUTIs). In this study, we verified the effectiveness of amikacin or gentamicin and ascorbic acid (AA) co-therapy in eliminating uropathogenic cells, as well as searched for the molecular basis of AA activity by applying chromatographic and fluorescent techniques. Under simulated physiological conditions, a combined activity of the antibiotic and AA supported the growth (threefold) of the P. mirabilis C12 strain, but reduced catheter colonization (≤30%) in comparison to the drug monotherapy. Slight modifications in the phospholipid and fatty acid profiles, as well as limited (≤62%) 2’,7’-dichlorofluorescein fluorescence, corresponding to the hydroxyl radical level, allowed for the exclusion of the hypothesis that the anti-biofilm effect of AA was related to membrane perturbations of the C12 strain. However, the reduced (≤20%) fluorescence intensity of propidium iodide, as a result of a decrease in membrane permeability, may be evidence of P. mirabilis cell defense against AA activity. Quantitative analyses of ascorbic acid over time with a simultaneous measurement of the pH values proved that AA can be an effective urine acidifier, provided that it is devoid of the presence of urease-positive cells. Therefore, it could be useful in a prevention of recurrent CAUTIs, rather than in their treatment. 相似文献
83.
Paulina Belvoncikova Martin Maronek Roman Gardlik 《International journal of molecular sciences》2022,23(18)
Gut microbiota dysbiosis has recently been reported in a number of clinical states, including neurological, psychiatric, cardiovascular, metabolic and autoimmune disorders. Yet, it is not completely understood how colonizing microorganisms are implicated in their pathophysiology and molecular pathways. There are a number of suggested mechanisms of how gut microbiota dysbiosis triggers or sustains extraintestinal diseases; however, none of these have been widely accepted as part of the disease pathogenesis. Recent studies have proposed that gut microbiota and its metabolites could play a pivotal role in the modulation of immune system responses and the development of autoimmunity in diseases such as rheumatoid arthritis, multiple sclerosis or type 1 diabetes. Fecal microbiota transplantation (FMT) is a valuable tool for uncovering the role of gut microbiota in the pathological processes. This review aims to summarize the current knowledge about gut microbiota dysbiosis and the potential of FMT in studying the pathogeneses and therapies of autoimmune diseases. Herein, we discuss the extraintestinal autoimmune pathologies with at least one published or ongoing FMT study in human or animal models. 相似文献
84.
Chávez-Díaz Mercedes Paulina Escudero-Rincón María Lorenza Chao Jesús Arce-Estrada Elsa Miriam Cabrera-Sierra Román 《Metallurgical and Materials Transactions A》2021,52(8):3570-3584
Metallurgical and Materials Transactions A - The effects of heat treatment on the hardness and electrochemical behavior of the Ti6Al4V alloy were studied. Two heat treatments were performed: one... 相似文献
85.
86.
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
87.
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
88.
Anita Dudek Maciej Spiegel Paulina Strugaa-Danak Janina Gabrielska 《International journal of molecular sciences》2022,23(10)
The relationship between the structure and the antiradical and antioxidant activities of three anthocyanidins, namely peonidin, petunidin, and delphinidin, and their glucosides was investigated in this study. The ability of anthocyanins to scavenge free radicals was determined using DPPH● assay, whereas the inhibition of peroxidation in liposomes in relation to a model membrane that imitated the composition of a lipid membrane in tumor cells was specified using the fluorimetric method. To explore this issue at the atomistic level, density functional theory studies were applied. It was shown that glycosides performed better than anthocyanidins in protecting membranes against oxidation. The highest redox potential was demonstrated by anthocyanidins with the highest number of hydroxyl groups in the B ring in the order as follows: (Dp > Pt > Pn), and the same relationship was proven for their glucosides. The majority of the compounds studied here proved to be better antioxidants than ascorbic acid. They showed consistent electrodonating properties and though the f-HAT mechanism became more feasible with each consecutive deprotonation. Glycosylation did not have a direct impact on reactivity, apart from peonidin and petunidin in the study of which it was found that this process was responsible for lifting off steric hindrance between B and C rings and rendering certain pathways more feasible. Kinetic and molecular dynamics are essential to properly describe the membrane’s lipid oxidation. 相似文献
89.
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
90.
Paulina de la MataAna Dominguez-Vidal Juan Manuel Bosque-Sendra Antonio Ruiz-MedinaLuis Cuadros-Rodríguez María José Ayora-Cañada 《Food Control》2012,23(2):449-455
Oil blends containing olive oil are commonly commercialized due to economical and nutritional reasons. According to European trade standards only when an oil blend contains more than 50% (w/w) of olive oil it can be marketed with images or graphics highlighting its presence. In this work a fast method for verifying the correct labelling of such oil blends was developed. First, the capability of attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy to distinguish olive oil was tested both in pure oil samples and in blends of different oils by using a method based on partial least squares discriminant analysis (PLS-DA). 100% of the olive oils samples were correctly identified within a wide collection of pure samples of different types of vegetable oils including olive oil of different categories, varieties and origin. When studying oil blends, it was possible to differentiate between blends with olive oil content higher than 50% (w/w) and below 50% (w/w). Finally, an attempt of quantification of olive oil in blends based on PLS regression was performed. For blend samples with olive oil contents up to 50% (w/w) a prediction error of 8.28 was obtained. 相似文献