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This research studied the phenolic content compared with the antioxidant properties of various O. vulgare (Lamiaceae) cultivars grown in Poland. The research results in this paper indicate that the dominant ingredient in all oregano cultivars was rosmarinic acid, known for its strong antioxidant properties. The highest amounts of rosmarinic acid (87.16 ± 4.03 mg/g dm) were identified in the O. vulgare spp. hirtum (Link) Ietsw. Other metabolites identified in the studied extracts include luteolin O-di-glucuronide-O-di-pentoside (30.79 ± 0.38 mg/g dm in the 'Aureum' cultivar), 4'-O-glucopyranosyl-3', 4'-dihydroxy benzyl-protocatechuate (19.84 ± 0.60 mg/g dm in the 'Margerita' cultivar), and p-coumaroyl-triacetyl-hexoside (25.44 ± 0.18 mg/g dm in the 'Margerita' cultivar). 'Hot & spicy' and 'Margerita' cultivars were characterized by the highest activity in eliminating OH⢠and O2â¢- radicals. Extracts from Greek oregano had the highest ability to scavenge DPPH radicals and chelate iron ions. This research has also provided new evidence that oregano has anti-migratory, cytotoxic properties and influences the viability of gastric cancer cells (the highest cytotoxicity was attributed to the 'Hot & spicy' cultivar, which performed the worst in antioxidant properties tests). Extracts from the tested cultivars at a concentration of 0.625% effectively inhibited the growth of S. aureus and P. aeruginosa bacteria. It seems that the oregano grown in Poland is of good quality and can be successfully grown on a large scale if the appropriate use is found.
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Antioxidantes , Origanum , Extratos Vegetais , Origanum/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Polônia , Antioxidantes/farmacologia , Antioxidantes/química , Humanos , Fenóis/farmacologia , Fenóis/análise , Fenóis/química , Cinamatos/química , Cinamatos/farmacologia , Cinamatos/análise , Antibacterianos/farmacologia , Antibacterianos/química , Depsídeos/farmacologia , Depsídeos/química , Ácido Rosmarínico , Linhagem Celular TumoralRESUMO
Purpose: The use of nanotechnology in medicine has gained attention in developing drug delivery systems. GO has the potential to deliver microRNA (miRNA) mimics or antisense structures. MiRNAs regulate gene expression and their dysregulation is implicated in diseases, including cancer. This study aims to observe changes in morphology, viability, mRNA expression of mTOR/PI3K/Akt and PTEN genes in U87, U118, U251, A172 and T98 glioblastoma cells and xenograft models after GO self-assembly with mimic miRNA-7. Methods: Colloidal suspension of graphene oxide (GO) was used for obtaining the GO-mimic miRNA-7 nanosystems by self-assembly method. The ultrastructure, size distribution and ATR-FTIR and UV-Vis spectrum were analyzed. The Zeta potential was measured to verify the stability of obtained nanosystem. The entrapment efficiency, loading capacity and released kinetics of mimic miRNA-7 form GO-mimic miRNA-7 nanosystems were analyzed. The transfection efficiency into the glioblastoma cell lines U87, U118, U251, A172 and T98 of mimic miRNA-7 delivered by GO nanosystems was measure by confocal microscopy and flow cytometry. The changes at mRNA expression level of mTOR, PI3K, AKT1 and PTEN genes was measured by qPCR analysis. The xenograft model of U87 and A172 tumour tissue was performed to analyze the effect at tumor size and volume after GO- mimic miRNA-7 nanosystem administration. Results: The ultrastructure of GO-mimic miRNA-7 nanosystems showed high affinity of mimic miRNA into the GO. The results of transfection efficiency, cell morphology and viability showed that GO -miRNA-7 effectively deliver mimics miRNA-7 into U87, U118, U251, A172 and T98 glioblastoma cells. This approach can reverse miRNA-7 expression's downstream effects and target the mTOR PI3K/Akt pathway observed at gene expression level, reducing xenograft tumour size and volume. Conclusion: The findings of the study could have significant implications for the development of advanced and precise GO based nanosystems specifically designed for miRNA therapy in cancer treatment.
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The study aimed to test the durability of coatings under natural conditions. The present study focused on the changes in wettability and additional properties of the coatings under natural conditions. The specimens were subjected to outdoor exposure and additionally immersed in the pond. Impregnating porous anodized aluminum is a popular production method for hydrophobic and superhydrophobic surfaces. However, prolonged exposure of such coatings to natural conditions causes leaching of the impregnate and, thus, the loss of hydrophobic properties. After the loss of hydrophobic properties, all kinds of impurities and fouling adhere better to the porous structure. Additionally, deterioration of anti-icing and anti-corrosion properties was observed. Finally, the self-cleaning, anti-fouling, anti-icing and anti-corrosion properties were comparable or even worse to those of the hydrophilic coating. In the case of superhydrophobic specimens, during outdoor exposure there was no loss of superhydrophobicity, self-cleaning and anti-corrosion properties. Still, despite this, the icing delay time dropped. During outdoor exposure, the structure, which initially had anti-icing properties, may degrade. Nevertheless, the hierarchical structure responsible for the superhydrophobic effect can still be preserved. The superhydrophobic coating initially had the best anti-fouling properties. However, the coating was also gradually losing its superhydrophobic properties during water immersion.
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This paper presents the results of an analysis of carbon (in the form of graphene oxide) deposited on the surface of threads made from stainless steel 316 and titanium alloy Ti6Al4V used in orthopedics using Laser Induced Breakdown Spectroscopy (LIBS). The aim of the article is to indicate the possibility of using the LIBS spectra for the study of thin layers, including graphene derivatives and other elements. Stratigraphic measurements allowed the detection of differences in the spectra peaks of individual elements, not only in the surface layer itself and in the native material, but also in the intermediate layer connecting the two layers. Due to the clear difference in the outline of the spectrum of graphene oxide and the spectrum of the native material of the samples analyzed, a clear incorporation of carbon atoms into the surface layer was observed. A factor analysis was performed, which confirmed the incorporation of graphene oxide into the surface layer of the native material of the elements examined.
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A material strength investigation along with a detailed microfractography analysis of fractures formed during static tensile tests of steel Armstal 550 was performed. The tests in this research were conducted in a temperature range of 298 to 973 K. In addition, during tensile tests at ambient temperature, optical measurements of strain maps and the curvature of the neck were performed. The minimum cross-sectional diameter and the radius of the neck curvature during tensile tests were obtained. The data can be directly used to obtain the true stress-strain curve. The material property analysis confirmed the high strength of the Armstal 550 alloy. The ultimate strength at room temperature equals 2.14 GPa, whereas the yield point equals 1.65 GPa. A decrease in the strength parameters along with an increase in temperature was noted. This is a typical phenomenon related to a change in the density and thermal expansion of steel under the influence of the temperature increase. For example, at a temperature of 500 °C, the ultimate strength is more than 50% less than at room temperature. An in-depth analysis of the metallography and microfractography of fractures resulting from static tensile tests showed the formation of atypical nano- and microstructures with an elongated shape. Local nano- and microstructures were observed at different levels of intensity for different temperatures. The largest clusters of nanoparticles were present on the surfaces of the specimens examined at a temperature of 973 K. Scanning microscopy analysis confirmed the presence of molybdenum oxides.
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This work shows the effect of graphene oxide deposition on microsieves' surfaces of gold and nickel foils, on DU 145 tumor cells of the prostate gland. The sieves were made by a laser ablation process. The graphene oxide (GO) deposition process was characterized by the complete covering of the inner edges of the microholes and the flat surface between the holes with GO. Electron microscanning studies have shown that due to the deposition method applied, graphene oxide flakes line the interior of the microholes, reducing the unevenness of the downstream surfaces during the laser ablation process. The presence of graphene oxide was confirmed by Fourier infrared spectroscopy. During the screening (sieving) process, the microsieves were placed in a sieve column. Gold foil is proven to be a very good material for the screening of cancer cells, but even more so after screening as a substrate for re-culture of the DU 145. This allows a potential recovery of the cells and the development of a targeted therapy. The sieved cells were successfully grown on the microsieves used in the experiment. Graphene oxide remaining on the surface of the nickel sieve has been observed to increase the sieving effect. Although graphene oxide improved separation efficiency by 9.7%, the nickel substrate is not suitable for re-culturing of the Du 145 cells and the development of a targeted therapy compared to the gold one.
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Grafite , Neoplasias da Próstata , Ouro/química , Ouro/farmacologia , Grafite/química , Grafite/farmacologia , Humanos , Masculino , Níquel/química , Níquel/farmacologia , Óxidos/química , Óxidos/farmacologia , PróstataRESUMO
The aim of this study was to obtain a superhydrophobic coating by modifying anodized aluminum using polydimethylsiloxane (PDMS). In order to obtain a superhydrophobic coating on an aluminum substrate, a multistage treatment was implemented. Specimens of aluminum were treated by abrasive blasting, anodization in sulfuric acid, impregnation by PDMS, rinsing in toluene to remove excess of PDMS, and curing. A rough surface with an additional low free energy layer on it resulted in a superhydrophobic effect. The coating obtained has an average contact angle of 159°. The specimens were tested in terms of durability in natural conditions. Additionally, anti-icing and anti-fouling properties were evaluated. The coating was compared with anodized aluminum obtained by a basic process.
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A near 1-keV photons from the Xe/He plasma produced by the interaction of laser beam with a double stream gas puff target were employed for studies of L absorption edges of period 4 transitional metals with atomic number Z from 26 to 30. The dual-channel, compact NEXAFS system was employed for the acquisition of the absorption spectra. L1-3 absorption edges of the samples were identified in transmission mode using broadband emission from the Xe/He plasma to show the applicability of such source and measurement system to the NEXAFS studies of the transition metals, including magnetic materials.
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This paper presents the results of investigations of the effect of graphene oxide and surface shot peening on the mechanical properties and fatigue life of bolts made of austenitic 304 steel. An innovative method for the uniform deposition of graphene oxide on screws is presented. The process involved activating the surface using plasma and then performing graphene oxide deposition using centrifugal force and vacuum drying. The screw specimens prepared in this way were subjected to a surface peening process. Comparative studies have shown that the combination of graphene oxide deposition and shot peening processes results in an increase in fatigue life of approximately 42 ÷ 275% (depending on the stress amplitude level) compared to the as-delivered samples. The results presented are promising and may provide a basis for further research on the application of graphene and its derivatives to increase fatigue life and improve the mechanical properties of machine components.
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This paper presents the effect of deposited graphene oxide coating on fatigue life of austenitic steel 1.4541 at 20 °C, 100 °C, and 200 °C. The study showed a decrease in the fatigue life of samples with a deposited graphene oxide layer in comparison with reference samples at 20 °C and 100 °C. However, an increase in fatigue life of samples with a deposited graphene oxide layer in comparison with reference samples occurred at 200 °C. This relationship was observed for the nominal stress amplitude of 370 and 420 MPa. Measurements of temperature during the tensile failure of the sample and microfractographic analysis of fatigue fractures were performed. Tests have shown that graphene oxide deposited on the steel surface provides an insulating layer. A higher temperature of the samples with a deposited graphene oxide layer was observed during fracture compared to the reference samples.
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This paper presents the results of the interaction of graphene oxide (GO) on MDA-MB-231 and SW-954 cancer cell lines. The tests were carried out in two variants. In the first one, GO was sprayed on a Petri dish and then, the cancer cell lines were cultured. In the second variant, the cells were covered with an aerosol containing GO. In both variants, cancer cell lines were incubated and tested every 24, 48, and 72 h. After each time period, cell viability and surface morphology were measured. The tests after 72 h showed that coating with GO aerosol caused a reduction in cell viability by 52.7% and 26.4% for MDA-MB-231 and SW-954 cancer cell lines, respectively, with respect to a reference sample (without the influence of GO aerosol). Tests where GO is a culture medium demonstrated a decrease in cell viability by approximately 4.3% compared to a reference sample for both considered cell lines.
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BACKGROUND: Graft-versus-host-disease (GvHD) is the major cause of morbidity and mortality after stem cell transplantation. The development of early prediction methods is therefore of importance. Our aim was to analyze the usefulness of early donor chimerism monitoring after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in T cells and in CD4+ and CD8+ (lineage chimerism) for GvHD prediction. MATERIAL AND METHODS: Chimerism was analyzed in 76 consecutive adult patients using RQ-PCR TaqMan technology on DNA extracted from Pan T, CD4+, and CD8+ cell subsets on Day 5, 10, 15 and 30 after allo-HSCT. RESULTS: The threshold of chimerism predictive for GvHD was the same for all tested cell subsets. In acute myeloid leukemia (AML) patients treated with myeloablative conditioning (MAC), the threshold predictive for acute graft versus host disease was 95% and 99% for Day 10 and Day 15, respectively. In patients treated with reduced intensity conditioning (RIC), the threshold predictive for chronic graft versus host disease was 98% on Day 10. The differences were statistically significant. CONCLUSIONS: Chimerism analysis in T cell subsets by RQ-PCR on Day 10 and Day 15 after transplantation is useful for prediction of aGvHD (AML patients after MAC) and cGvHD (patients after RIC). However, there was no difference in the results between chimerism in the T cell subsets. Our RQ-PCR protocol was highly sensitive and proved effective for analysis of lineage chimerism.
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Quimerismo , Doença Enxerto-Hospedeiro/etiologia , Neoplasias Hematológicas/cirurgia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Transplante de Células-Tronco/efeitos adversos , Doença Aguda , Adolescente , Adulto , Doença Crônica , Estudos de Coortes , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Doença Enxerto-Hospedeiro/diagnóstico , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/patologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Polônia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Estatísticas não Paramétricas , Transplante de Células-Tronco/métodos , Subpopulações de Linfócitos T/imunologia , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Adulto JovemRESUMO
UNLABELLED: It is recommended that all patients after allogeneic hematopoietic stem cell transplantation (alloHSCT) should be monitored for CMV infection markers. The aim of the study was to check the usefulness of quantitative DNA CMV monitoring after alloHSCT. MATERIAL AND METHOD: DNA CMV was tested by real-time PCR in sera and blood samples twice a week until 30th day after alloHSCT thereafter, once a week until 100th day and then, once every 2-3 weeks. 832 samples from 16 patients were tested. All patients were anti-CMV positive or/and received stem cells from seropositive donors. Introduction of antiviral treatment was based on initial viral load and its rate of increase. RESULTS: DNA CMV was detected in 13/16 patients; in 3 before 30h day after allo HSCT (group I) and in 10 (group II) after 30th day. In all patients from group I clinical symptoms were observed and DNA CMV was detected in sera and blood samples. Peak viral load was 2490-34 620 geq/ml. Although antiviral treatment was applied, reinfection was observed and infection lasted from 28 to 91 days. In 6 group II patients, clinical symptoms were observed and DNA CMV in sera and blood was detected for 16-56 days, DNA CMV peak load was 100-8950 geq/ml. In the remaining 4 patients, no clinical symptoms were observed--DNA CMV was detected in blood only for 7 to 14 days. In one patient with peak viral load 10,540 geq/ml, antiviral treatment was applied. In 3 with viral load of 400-2000 geq/ml, treatment was not introduced. The quantitative DNA CMV results were taken into account before the change of antiviral drugs for more effective drugs and the decrease of drug dose due to side effects. CONCLUSIONS: Application of quantititative DNA CMV testing allowed to optimise antiviral drug administration in immunosupressed patients after alloHSCT