Search Results (870)

Background Plasma membrane proteins (PMPs) play key roles in cell signalling, adhesion, and trafficking, and are attractive therapeutic targets in cancer due to their surface accessibility. However, their typically low abundance limits detection by conventional proteomic approaches. Methods: To improve PMP detection, we employed a surface proteomics workflow combining cell surface biotinylation and affinity purification prior to LC-MS/MS analysis in cervical (SiHa) and bladder (UMUC3) cancer cell lines cultured under normoxic (21% O₂) or hypoxic (0.1% O₂) conditions. Results: In SiHa cells, 43 hypoxia-upregulated proteins were identified exclusively in the biotin-enriched fraction, including ITGB2, ITGA7, AXL, MET, JAG2, and CAV1/CAV2. In UMUC3 cells, 32 unique upregulated PMPs were detected, including CD55, ADGRB1, SLC9A1, NECTIN3, and ACTG1. These proteins were not observed in corresponding whole-cell lysates and are associated with extracellular matrix remodelling, immune modulation, and ion transport. Biotinylation enhanced the detection of membrane-associated pathways such as ECM organisation, integrin signalling, and PI3K–Akt activation. Protein–protein interaction analysis revealed links between membrane receptors and intracellular stress regulators, including mitochondrial proteins. Conclusions: These findings demonstrate that surface biotinylation improves the sensitivity and selectivity of plasma membrane proteomics under hypoxia, revealing hypoxia-responsive proteins and pathways not captured by standard whole-cell analysis. Full article

Platinum has emerged as an optimal catalyst for the selective hydrogenation of nitroarenes owing to its high hydrogenation activity, selectivity, and stability. In this study, we report the fabrication of platinum nanoparticles stabilized on a composite support consisting of gum acacia polymer (GAP) and TiO₂. It was engineered for the targeted reduction of nitroarenes to arylamines via selective hydrogenation in methanol at ambient temperature. The non-toxic and biocompatible properties of GAP enable it to act as a reducing and stabilizing agent during synthesis. The synthesized nanocatalyst was characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Morphological and structural analyses revealed that the fabricated catalyst consisted of minuscule Pt nanoparticles integrated within the GAP framework, accompanied by the corresponding TiO₂ nanoparticles. Inductively coupled plasma optical emission spectrometry (ICP-OES) was employed to ascertain the Pt content. The mild reaction conditions, decent yields, trouble-free workup, and facile separation of the catalyst make this method a clean and practical alternative to nitroreduction. Selective hydrogenation yielded an average arylamine production of 97.6% over five consecutive cycles, demonstrating the stability of the nanocatalyst without detectable leaching. Full article

The functional role of MAPKK genes in potato (Solanum tuberosum L.) under high-temperature stress remains unexplored, despite their critical importance in stress signaling and yield protection. We characterized StMAPKK1, a novel group D MAPKK localized to plasma membrane/cytoplasm. Quantitative real-time polymerase chain reaction (qRT-PCR) revealed cultivar-specific upregulation in potato (‘Atlantic’ and ‘Desiree’) leaves under heat stress (25 °C, 30 °C, and 35 °C). Transgenic lines overexpressing (OE) StMAPKK1 exhibited elevated antioxidant enzyme activity, including ascorbate peroxidase (APX), catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), mitigating oxidative damage. Increased proline and chlorophyll accumulation and reduced oxidative stress markers, hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), indicate improved cellular redox homeostasis. The upregulation of key antioxidant and heat stress-responsive genes (StAPX, StCAT1/2, StPOD12/47, StFeSOD2/3, StMnSOD, StCuZnSOD1/2, StHSFA3 and StHSP20/70/90) strengthened the enzymatic defense system, enhanced thermotolerance, and improved photosynthetic efficiency, with significant improvements in net photosynthetic rate (Pn), transpiration rate (E), and stomatal conductance (Gs) under heat stress (35 °C) in StMAPKK1-OE plants. Superior growth and biomass (plant height, plant and its root fresh and dry weights, and tuber yield) accumulation, confirming the positive role of StMAPKK1 in thermotolerance. Conversely, RNA interference (RNAi)-mediated suppression of StMAPKK1 led to a reduction in enzymatic activity, proline content, and chlorophyll levels, exacerbating oxidative stress. Downregulation of antioxidant-related genes impaired ROS scavenging capacity and declines in photosynthetic efficiency, growth, and biomass, accompanied by elevated H₂O₂ and MDA accumulation, highlighting the essential role of StMAPKK1 in heat stress adaptation. These findings highlight StMAPKK1’s potential as a key genetic target for breeding heat-tolerant potato varieties, offering a foundation for improving crop resilience in warming climates. Full article

This study presents a photoresist-free patterning method for solution-processed indium zinc oxide (IZO) thin films using two photochemical exposure techniques, namely pulsed ultraviolet (UV) light and UV-ozone, and a plasma-based method using oxygen (O₂) plasma. Pulsed UV light delivers short, high-intensity flashes of light that induce localised photochemical reactions with minimal thermal damage, whereas UV-ozone enables smooth and uniform surface oxidation through continuous low-pressure UV irradiation combined with in situ ozone generation. By contrast, O₂ plasma generates ionised oxygen species via radio frequency (RF) discharge, allowing rapid surface activation, although surface damage may occur because of energetic ion bombardment. All three approaches enabled pattern formation without the use of conventional photolithography or chemical developers, and the UV-ozone method produced the most uniform and clearly defined patterns. The patterned IZO films were applied as active layers in bottom-gate top-contact thin-film transistors, all of which exhibited functional operation, with the UV-ozone-patterned devices exhibiting the most favourable electrical performance. This comparative study demonstrates the potential of photochemical and plasma-assisted approaches as eco-friendly and scalable strategies for next-generation IZO patterning in electronic device applications. Full article

This work investigates on how Fe incorporation influences the surface, microstructural, and optical properties of solution precursor plasma-sprayed TiO₂ coatings. The Fe-TiO₂ coatings were prepared using titanium isopropoxide and iron acetylacetonate as precursors, with ethanol as the solvent. X-ray diffraction analysis revealed the existence of both anatase and rutile TiO₂ phases, with a predominant rutile phase, also confirmed by Raman spectroscopy. There was an increase in the anatase crystals upon the addition of Fe ions. A longer spray distance further enhanced the anatase content and reduced the average TiO₂ crystallite sizes present in the Fe-added coatings. SEM cross-sectional images displayed finely grained, densely packed deposits in the Fe-added coatings. UV-Vis spectroscopy showed visible-light absorption by the Fe-TiO₂ coatings, with reduced band gap energies ranging from 2.846 ± 0.002 eV to 2.936 ± 0.003 eV. Photoluminescence analysis showed reduced emission intensity at 356 nm (3.48 eV) for the Fe-TiO₂ coatings. These findings confirm solution precursor plasma spray to be an effective method for developing Fe-TiO₂ coatings with potential application as visible-light-active photocatalysts. Full article

Vibrio parahaemolyticus is the leading cause of bacterial diarrhea in humans from shellfish consumption. In Thailand, blood clam is a popular shellfish, but homemade cooking often results in insufficient heating. Therefore, consumers may suffer from food poisoning due to Vibrio infection. This study aimed to determine the effect of chitooligosaccharide conjugated with epigallocatechin gallate (COS-EGCG) at different concentrations (200 and 400 ppm) combined with high-voltage atmospheric cold plasma (HVACP) on inhibiting V. parahaemolyticus in vitro and in challenged blood clam meat. Firstly, HVACP conditions were optimized for gas composition and treatment time (20 and 60 s); a 70% Ar and 30% O₂ gas mixture resulted in the highest ozone formation and a treatment time of 60 s was used for further study. COS-EGCG conjugate at 400 ppm with HVACP (ACP-CE400) completely killed V. parahaemolyticus after incubation at 37 °C for 6 h. Furthermore, an antibacterial ability of ACP-CE400 treatment against bacterial cells was advocated due to the increased cell membrane damage, permeability, and leakage of proteins and nucleic acids. Scanning electron microscopy (SEM) showed cell elongation and pore formation, while confocal microscopy revealed disrupted biofilm formation. Additionally, the shelf life of challenged blood clam meat treated with ACP-CE400 was extended to nine days. SEM analysis revealed damaged bacterial cells on the meat surface after ACP-CE400 treatment, indicating the antibacterial activity of the combined treatment. Thus, HVACP combined with COS-EGCG conjugate, especially at a highest concentration (400 ppm), effectively inhibited microbial growth and extended the shelf life of contaminated blood clam meat. Full article

The rapid evolution of pathogens and the limited genetic diversity of hosts are two major factors contributing to the plant pathogenic phenomenon known as the loss of disease resistance in maize (Zea mays L.). It has emerged as a significant biological stressor threatening the global food supplies and security. Based on previous cross-species homologous gene screening assays conducted in the laboratory, this study identified the maize disease-resistance candidate gene ZmNLR-7 to investigate the maize immune regulation mechanism against Bipolaris maydis. Subcellular localization assays confirmed that the ZmNLR-7 protein is localized in the plasma membrane and nucleus, and phylogenetic analysis revealed that it contains a conserved NB-ARC domain. Analysis of tissue expression patterns revealed that ZmNLR-7 was expressed in all maize tissues, with the highest expression level (5.11 times) exhibited in the leaves, and that its transcription level peaked at 11.92 times 48 h post Bipolaris maydis infection. Upon inoculating the ZmNLR-7 EMS mutants with Bipolaris maydis, the disease index was increased to 33.89 and 43.33, respectively, and the lesion expansion rate was higher than that in the wild type, indicating enhanced susceptibility to southern corn leaf blight. Physiological index measurements revealed a disturbance of ROS metabolism in ZmNLR-7 EMS mutants, with SOD activity decreased by approximately 30% and 55%, and POD activity decreased by 18% and 22%. Moreover, H₂O₂ content decreased, while lipid peroxide MDA accumulation increased. Transcriptomic analysis revealed a significant inhibition of the expression of the key genes NPR1 and ACS6 in the SA/ET signaling pathway and a decrease in the expression of disease-related genes ERF1 and PR1. This study established a new paradigm for the study of NLR protein-mediated plant immune mechanisms and provided target genes for molecular breeding of disease resistance in maize. Overall, these findings provide the first evidence that ZmNLR-7 confers resistance to southern corn leaf blight in maize by synergistically regulating ROS homeostasis, SA/ET signal transduction, and downstream defense gene expression networks. Full article

Korean rockfish, Sebastes schlegeli, a coastal species, is vulnerable to pollutants such as microplastics and bacteria. While interactions between microplastics and other pollutants have been studied, little is known about microplastic and bacteria interactions. This study examined the effects of combined exposure to polystyrene microplastics in the form of microbeads (MB; 0.2 µm, 5 and 50 beads/L) and Streptococcus iniae (1 × 10⁵ and 1 × 10⁷ CFU/mL) for five days on oxidative stress and apoptosis in Korean rockfish. We assessed the mRNA expression and activity of oxidative stress markers (SOD, CAT, H₂O₂, NO, CYP1A1, GST), plasma LPO levels, and caspase-3 expression in liver tissue. Co-exposure to high MB and S. iniae concentrations significantly elevated oxidative stress and apoptosis markers, suggesting enhanced toxicity. This may result from MB facilitating pathogen transport into the fish, indicating microplastics can act as vectors for bacterial infection in aquatic environments. Full article

In this study, the process of electrolytic–plasma nitrocarburizing (EPNC) of 20-grade steel was investigated using various electrolytes and temperature regimes. At the first stage, optical spectral analysis of plasma emission during EPNC was carried out with spectral registration in the range of 275–850 nm, which allowed the identification of active components (Hα, CN, Fe I, O I lines, etc.) and the calculation of electron density. Additionally, the EPNC process was recorded using a high-speed camera (1500 frames per second), which made it possible to visually evaluate the dynamics of arc and glow discharges under varying electrolyte compositions. At the next stage, the influence of temperature regimes (650 °C, 750 °C, and 850 °C) on the formation of the hardened layer was studied. Using SEM and EDS methods, the morphology, phase zones, and the distribution of chemical elements were determined. Microhardness measurements along the depth and friction tests were carried out. It was found that a temperature of 750 °C provides the best balance between the uniformity of chemical composition, high microhardness (~800 HV), and a minimal coefficient of friction (~0.48). The obtained results confirm the potential of the selected EPNC regime for improving the performance characteristics of 20-grade steel. Full article

P-glycoprotein (P-gp) is a key element of cancer treatment resistance, actively extruding cytotoxic drugs from cells and diminishing their efficacy. While its role at the plasma membrane is well established, its intracellular localization, particularly on lysosomes, is increasingly recognized as a critical contributor to drug resistance. This study investigates four innovative LightSpot fluorescent compounds to detect and quantify both membrane and lysosomal P-gp in Triple-Negative Breast Cancer (TNBC) SUM1315 and DU4475 cell lines. Results highlighted lysosomal P-gp staining by the LightSpot-FL-1, LightSpot-BrX-1, and LightSpot-BdO-1 fluorescent compounds (Mander’s coefficients > 0.8 overlapping with LAMP2 immunostaining). After both cell lines were exposed to Olaparib, a significant increase in P-gp expression level and lysosomal distribution of P-gp was detected. Indeed, after 100 µM Olaparib exposure, LightSpot-FL-1 allowed us to quantify an increase in P-gp-positive lysosome number of 1293 and 334% for SUM1315 and DU4475 cells, respectively, compared to the control. Findings suggest that P-gp may relocate to lysosomes upon drug exposure, highlighting a dual resistance mechanism involving both membrane and lysosomal P-gp. This study demonstrated the potential of LightSpot fluorescent compounds to evaluate P-gp-mediated cell resistance to treatment and emphasized the need to assess global cell P-gp expression to improve cancer diagnosis. Full article

Reactive oxygen–nitrogen species (RONS) production in a Peltier-cooled hybrid dielectric barrier discharge (HDBD) reactor operated with humid air is characterized. Fourier-transform infrared spectroscopy (FTIR) is used to determine the RONS in the HDBD-produced gases. The presence of molecules ${\mathrm{O}}_3$, ${\mathrm{NO}}_2$, ${\mathrm{N}}_2$O, ${\mathrm{N}}_2{\mathrm{O}}_5$, and ${\mathrm{HNO}}_3$ is evaluated. The influence of HDBD reactor operation parameters on the FTIR result is discussed. The strongest influence of Peltier cooling on RONS chemistry is reached at conditions related to a high specific energy input (SEI): high voltage and duty cycle of plasma width modulation (PWM), and low gas flow. Both PWM and Peltier cooling can achieve a change in the chemistry from oxygen-based to nitrogen-based. ${\mathrm{N}}_2{\mathrm{O}}_5$ and ${\mathrm{HNO}}_3$ are detected at a low humidity of 7% in the reactor input air but not at humidity exceeding 90%. In addition to the FTIR analysis, the plasma-activated water (PAW) is investigated. PAW is produced by bubbling the HDBD plasma gas through 12.5 mL of distilled water in a closed-loop circulation at a high SEI. Despite the absence of ${\mathrm{N}}_2{\mathrm{O}}_5$ and ${\mathrm{HNO}}_3$ in the gas phase, the acidity of the PAW is increased. The pH value decreases on average by 0.12 per minute. Full article

The application of non-thermal (cold) plasmas is considered an environmentally friendly method that could affect plant metabolism and cellular development or can be used for the commercial production of natural products that cannot be chemically synthesized. In the present study, the non-embryogenic callus of iris (Iris reichenbachii Heuff.) was treated with a Radio Frequency (RF) plasma needle device using He as a working gas. We investigated short-term (up to seven days) and long-term (up to one year) changes on morphological, physiological and biochemical levels. An increased production of O₂⁻ and H₂O₂ was observed in the callus tissue after plasma treatment. The enzymes SOD and CAT represented the frontline in the antioxidant defense against reactive oxygen species (ROS) produced during the first hour of treatment, while POX was the leading antioxidant enzyme seven days after plasma treatment. Significant long-term morphological changes were observed in the calli due to the increased mitotic activity of the plant cells. In addition, three flavonoids (naringenin, apigenin and acacetin) and two isoflavonoids (irisolidone and irilone) were detected only in the plasma-treated tissue even one year after plasma treatment. The present study emphasizes the application of the plasma technique to promote meristematic activity and stimulate the production of specialized metabolites in iris calli. Full article

In this review article, statistical mechanisms of oxidative modification reactions in various organic compounds under the influence of reactive oxygen species (ROS) generated by cold atmospheric plasma (CAP) are investigated and analyzed based on reactive molecular dynamics (MD) simulations. As an efficient and hygienic advanced oxidation technology, CAP demonstrates tremendous potential in fields such as biomedicine and environmental protection. Through simulations, this paper provides a detailed analysis of the interaction mechanisms between ROS and components of biological tissues and environmental toxins. In this paper, we review the reactions involving four major ROS (OH radicals, O atoms, ${\mathrm{O}}_3$ molecules, and ${\mathrm{H}}_2{\mathrm{O}}_2$ molecules) and organic compounds, including proteins, DNA, polysaccharides, fatty acids, antibiotics, and mycotoxins. Atomic-level analysis reveals various oxidative modification reactions induced by ROS and their resulting products, including dehydrogenation reactions, bond-formation reactions, oxygen-addition reactions, and bond-cleavage reactions. Additionally, the study elucidates the role of active functional groups in various organic compounds, the presence of special elements, and the specific reactive nature of ${\mathrm{H}}_2{\mathrm{O}}_2$. Furthermore, the influence of different ROS species and concentrations on reaction types is explored, aiming to provide a solid theoretical foundation for the application of CAP technology in biomedicine and environmental remediation. Full article

Thin, dense and nanocrystal bismuth oxide films were prepared by the in situ plasma-assisted reactive evaporation (ARE) method using lead doping. Thin films were deposited at room temperature and at 500 °C temperature on glass and silicon substrates. X-ray diffraction, SEM, EDS, and optical measurements were applied to characterize these bismuth oxide films. The results showed that it is possible to synthesize the δ-Bi₂O₃ phase thin films at a temperature lower than 729 °C using an plasma-assisted reactive evaporation (ARE) method and stabilize it (to room temperature) using the additives of lead oxide. The influence of lead oxide concentration on phase formation was investigated. The optimal amount of lead oxide dopant was determined. An excess of lead oxide concentration forms PbO and δ-Bi₂O₃ mixture phases and nanorods appear in films. The synthesized δ-Bi₂O₃ phase was metastable; it transformed into the β-Bi₂O₃ phase after thermal impact during impedance measurements. The cross section of thin film sample shows the dense and monolithic structure. Optical measurements show that the optical band gap increases with increasing lead concentration. It was found that the highest total ionic conductivity of (Bi_1−xPb_0.26)₂O₃ is 0.165 S/cm at 1073 K temperature and activation energy is ΔE_tot = 0.5 eV. Full article

Volatile Organic Compounds (VOCs) are pervasive environmental pollutants with significant implications for air quality and human health. The development of effective technologies for VOC degradation is essential to mitigate their adverse effects. Microwave plasma technology has emerged as a promising solution for VOC abatement due to its ability to generate highly reactive species at ambient conditions, enabling efficient decomposition of VOCs into harmless byproducts. Concurrently, Density Functional Theory (DFT) has become a critical tool for understanding the molecular-level mechanisms of VOC degradation, providing insights into reaction pathways and energy dynamics. This study explores the integration of microwave plasma experiments with DFT simulations to investigate the degradation mechanisms of VOCs under plasma conditions. DFT calculations of microwave plasma degradation for toluene are performed. The results show that on the one hand, toluene can undergo ring-opening. Then, these active molecules or groups react with active free radicals and are ultimately oxidized into CO₂ and H₂O. On the other hand, VOC gas molecules react with active free radicals (O, OH) generated by background gas (O₂ and H₂O) through oxidation reactions, generating organic intermediates such as benzene, benzyl alcohol, and benzoic acid, respectively, which are finally oxidized into CO₂ and H₂O. Our theoretical research results are expected to provide profound insights into the degradation mechanisms of these aromatic hydrocarbon VOCs through microwave plasma and also contribute to a better understanding of the further degradation mechanisms of air pollutants at the molecular level. Full article