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Cold atmospheric plasma (CAP) is a promising complement to tissue repair and regenerative medicine approaches. CAP has therapeutic potential in infected cutaneous wounds by mechanisms which remain enigmatic. Here, CAP is shown to activate phagocyte NADPH oxidase complex NOX2. CAP induced increased intracellular reactive oxygen species, alleviated by NOX2 inhibitors. Genetic and pharmacological inhibitions of NOX2 in macrophages and bioengineered skin infected with Staphylococcus aureus and treated with CAP reduced intracellular oxidants and increased bacterial survival. CAP triggered Rac activation and phosphorylation of p40phox and p47phox required for NOX2 assembly and activity. Furthermore, CAP induced collagen I expression by fibroblasts. Infection and healing kinetics showed that murine skin wounds infected with S. aureus and treated with CAP are characterized by decreased bacterial burden, increased length of neoepidermis and extracellular matrix formation. Collectively, our findings identify mechanisms triggered by CAP that subdue infection and result in enhanced repair following skin injury. [ABSTRACT FROM AUTHOR]

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Wastewater treatment plants (WWTPs) have been implicated as direct key reservoir of both antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) associated with human infection, as high concentrations of ARBs and ARGs have been detected in recycled hospital wastewater. Among the ARBs, the carbapenem-resistant Acinetobacter baumannii has been ranked as priority 1 (critical) pathogen by the World Health Organization (WHO), due to its overwhelming burden on public health. Therefore, this study is aimed at investigating non-thermal plasma (NTP) technology as an alternative disinfection step to inactivate this bacterium and its ARGs. Culture-based method and PCR were employed in confirming the carbapenem resistance gene blaNDM-1 in A. baumannii (BAA 1605). Suspension of carbapenem-resistant A. baumannii (24 h culture) was prepared from the confirmed isolate and subjected to plasma treatment at varying time intervals (3 min, 6 min, 9 min, 12 min, and 15 min) in triplicates. The plasma-treated samples were evaluated for re-growth and the presence of the resistance gene. The treatment resulted in a 1.13 log reduction after 3 min and the highest log reduction of ≥ 8 after 15 min, and the results also showed that NTP was able to inactivate the blaNDM-1 gene. The log reduction and gel image results suggest that plasma disinfection has a great potential to be an efficient tertiary treatment step for WWTPs. [ABSTRACT FROM AUTHOR]

Cold atmospheric plasma (CAP) has been reported as a promising technique in dentistry. The biosafety and mechanisms on periodontal tissue are especially important in clinical practice. This study aims to evaluate the cytotoxicity, genotoxicity and mechanisms of human periodontal ligament fibroblasts (hPDLFs) induced by CAP. The antimicrobial effect on Porphyromonas gingivalis (P. gingivalis) was evaluated using the colony-forming unit methods (CFU). Human periodontal ligament fibroblasts were treated with CAP for variable times (1, 2, 4, 8, and 16 min). CCK-8 assays were performed to detect cell viability and flow cytometry was performed to measure the cell cycle and apoptosis. Cell migration ability was determined by scratch assays. The physicochemical properties of plasma activated medium were evaluated, including the pH values, H2O2 and NO levels. DCF-DA staining and analysis were performed to evaluate intracellular ROS levels inside cells using flow cytometry. Immunofluorescence of DNA double-strand breaks (DSBs) marker, phosphorylated γH2AX was used to establish the genotoxicity of plasma. The results showed that CAP has a significant inhibition effect of P. gingivalis after 6 min treatment. It has significantly dose-dependent effects that ranging from increasing cell proliferation to inducing apoptosis. A low doses (1, 2, 4, and 8 min) could enhance the cell proliferation. A high dose (16 min) resulted in the inhibition of cell proliferation (p < 0.01). It is also shown that these effects are primarily due to the formation of reactive oxygen and nitrogen species (RONS). [ABSTRACT FROM AUTHOR]

Androgenetic alopecia (AGA) is a chronic and progressive form of hair loss characterized by vascular degeneration in the perifollicular microenvironment, leading to cell apoptosis and eventual loss of hair follicles (HFs). Traditional therapeutic formulations, such as Minoxidil (MXD) tincture, have limitations in reshaping the perifollicular microenvironment and exhibit limited effectiveness. Here, we report a multi-synergistic therapeutic platform for high-performance hair regeneration therapy. The platform combines microneedle (MN) patches loaded with MXD-encapsulated nanostructured lipid carriers (MXD-NLC-MNs) and cold atmospheric plasma (CAP). The MNs' mechanical strength enables efficient transdermal delivery of MXD to the targeted dermal papilla cells, promoting cell proliferation. Furthermore, in collaboration with MXD, the mechanical stimulation exerted by MN application synergistically upregulates the expression of vascular endothelial growth factor, leading to neoangiogenesis. Meanwhile, the transient microchannels in the skin created by MNs facilitate the transdermal delivery of CAP-generated nitric oxide (NO) to the sites of HF lesions, whereby the synergistic interaction between MXD and NO boosts perifollicular vasodilation. Consequently, the perifollicular microenvironment can be effectively reshaped to accelerate hair regeneration in AGA murine models. This multi-synergistic combination therapy strategy would hold great promise for effectively treating AGA and promoting hair regrowth. [ABSTRACT FROM AUTHOR]

Phenanthrene (PHE) is a polycyclic aromatic hydrocarbon categorized as a high priority organic pollutant being toxic for the ecosystem and human health, and its sorption on natural organic or inorganic substances seems a well-promising method for its removal from water streams. The goals of the present work are (i) to assess the capacity of low-cost adsorbents fabricated by treating coffee wastes and diatomaceous earth to remove PHE from water; (ii) to elucidate the role of the pore structure on PHE sorption dynamics; and (iii) to assess the potential to regenerate adsorbents loaded with PHE, by using the novel technology of cold atmospheric plasma (CAP). Diatomaceous earth (DE) and DE pre-treated with sodium hydroxide (NaOH) or phosphoric acid (H3PO4) were chosen as inorganic adsorbents. Coffee waste (CW) and activated carbons (AC) produced from its pyrolysis at 800 °C (CWAC), either untreated (CWAC-800) or pre-treated with NaOH (CWAC-NaOH-800) and H3PO4 (CWAC-H3PO4-800), were chosen as organic adsorbents. The adsorbents were characterized with nitrogen adsorption–desorption isotherms, attenuated total reflectance-Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and mercury intrusion porosimetry. Based on the PHE sorption capacity and pore structure/surface characteristics, the CWAC-NaOH-800 was chosen as the most efficient adsorbent for further equilibrium and kinetic sorption studies. The multi-compartment model was used to describe the PHE sorption dynamics in CWAC-NaOH-800 by accounting for the pore/surface diffusion and instantaneous sorption. The CWAC-NaOH-800 exhibited remarkable values for (i) the specific surface area (SBET = 676.5 m2/g) and meso- and micro-pore volume determined by nitrogen sorption (VLN2 = 0.415 cm3/g); (ii) the macro- and meso-pore volume determined by mercury intrusion porosimetry (VMIP = 3.134 cm3/g); and (iii) the maximum PHE sorption capacity (qmax = 142 mg/g). The percentage of adsorbent recovery after its regeneration with CAP was found to be ~ 35%. From the simulation of sorption dynamics, it was found that at early times, the sorption kinetics is governed by the film diffusion towards the external surface of grains, but at late times, most of the adsorbed mass is transferred primarily to meso-/macro-pores via diffusion, and secondarily to micro-porosity via surface diffusion. Based on the adsorbent characteristics, effect of pH on sorption efficiency, and numerical analysis of sorption dynamics, it was concluded that probably the dominant adsorption mechanism is the π-π interactions between hydrophobic PHE aromatic rings and CWAC-NaOH-800 graphene layers. The high PHE removal efficiency of CWAC-NaOH-800, the successful interpretation of sorption dynamics with the multi-compartment model, and the potential to regenerate PHE-loaded adsorbents with the green and economic technology of CAP motivate a strategy for testing CWACs towards the adsorption of other PAHs, application of adsorbents to real wastewaters, and scaling-up to pilot units. [ABSTRACT FROM AUTHOR]

This article discusses the issue of indoor ozone in research laboratories, particularly during the COVID-19 pandemic. While outdoor ozone has both beneficial and detrimental effects, indoor ozone is often overlooked and can pose health risks. The article explores ozone formation, its use in research, health effects, incidents of ozone poisoning, and guidelines for safety in laboratories. It emphasizes the need for proper handling and monitoring of ozone in indoor laboratory spaces to ensure the safety of workers. The article also highlights the age and gender-specific susceptibility to ozone exposure and provides recommendations for improving safety in laboratories. [Extracted from the article]

This comprehensive review explores decade-long research conducted on the applications of Cold Atmospheric Plasma (CAP) and Plasma Activated Liquids (PAL), including Plasma Activated Water (PAW), in the fields of Medicine and Dentistry. CAPs, operating at atmospheric pressure, offer unique advantages over conventional medical devices, generating Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) that interact with substances, enabling diverse applications. The review examined CAP and PAL efficacy against infectious diseases using in vitro, ex vivo, in vivo, and direct application methods. Significant strides were observed in wound healing, cancer treatment, and dental care. However, ensuring patient safety through rigorous plasma source standards remains crucial. The study underscores CAPs and PALs' potential to transform medical and dental therapies, urging further research and development in these groundbreaking technologies. These findings highlight the transformative impact of CAPs and PALs, offering promising avenues for innovative medical and dental treatments. [ABSTRACT FROM AUTHOR]

The bioavailability and quality attributes of egg white proteins (EWPs) are vital for food products' final form and nutritional content. Heat treatment negatively affects these attributes. We investigated EWP's functional, rheological, and structural characteristics using dielectric barrier discharge cold atmospheric plasma (DBD-CAP) for its advantages to address this. EWP was exposed to different DBD-CAP treatment times (0, 60, 120, 180, 240, and 300 s) at 40 kV. Assessing functional attributes revealed increasing solubility and decreasing turbidity with longer plasma treatment. As plasma treatment time increased, foam and emulsion stabilities and capacities improved, along with enhanced water and oil-holding capacities. DBD-CAP influenced EWP's rheological attributes, showing alterations between native and treated EWP, with no significant differences within plasma treatment times. EWP's unfolding was confirmed by increased lipid oxidation, carbonyl content, hydrophobicity, and decreased sulfhydryl group. Particle sizes and zeta potential of plasma-treated EWP decreased with treatment time. FTIR-ATR and CD analyses revealed DBD-CAP's impact on EWP's conformation. CD indicated modifications in the secondary structure, increasing α-helix, β-sheets, and β-turns and decreasing random coils. These findings suggest that plasma-induced mild oxidation enhances EWP's attributes and structure, potentially benefiting its utilisation in the food industry. [ABSTRACT FROM AUTHOR]

Cold atmospheric plasma (CAP) as an emerging nonthermal technology holds great potential in food sterilization and biopolymer modification. The antibacterial effect of CAP on spoilage fungi and its effects on physicochemical and nutritional properties in yam flour were both studied. The results show that CAP treatment for 5–20 min achieved a microbial reduction of Fusarium moniliforme ranging from 0.56 to 2.40 log10 CFU/g at day 0 and 1.50 to 3.73 log10 CFU/g at day 9. The inactivation efficiency was increased with the CAP treatment time and storage time. For the physicochemical properties, CAP caused surface corrosion and formed aggregations on the surface of flour granules, as well as enhanced the absorption of carboxyl or carbonyl peak at 1730 cm−1. The swelling power, starch solubility, and pasting viscosity of Chinese yam flour were increased after CAP treatment, while the endothermic enthalpy was decreased possibly due to the disruption of the amorphous and crystalline structure of starch granules. A distinct color change was observed in CAP-treated Chinese yam flour, which became more bright and less yellow. The results of nutritional properties demonstrate that CAP caused a redistribution of dietary fiber components from insoluble to soluble fractions and changed the amino acid composition in Chinese yam flour. The SDS-PAGE analysis confirmed that CAP treatment could degrade or depolymerize the macromolecular proteins into small molecular subunits. Thus, CAP can be a promising technology to modify the physicochemical and nutritional properties of Chinese yam flour and ensure its microbial safety. [ABSTRACT FROM AUTHOR]

A system for microwave diagnostics of low-temperature non-stationary atmospheric plasma jets is proposed, the principle of operation of which is based on the registration of changing in the quality factor of the main mode of the electric type of a cylindrical microwave cavity resonator. The time dependences of the average volumetric conductivity of a plasma jet of a barrier discharge in a helium flow are measured. The discharge was powered from an alternating voltage source with a frequency of 9 kHz. Such a low frequency of the supply voltage made it possible to distinguish individual pulses of breakdowns of the barrier discharge. [ABSTRACT FROM AUTHOR]

The aim of the present study was the direct comparison of two popular minerals, bauxite and palygorskite, as adsorbents for the removal of cephalexin (CPX) from aqueous solutions and the regeneration of the spent adsorbents through cold atmospheric plasma. Batch kinetics and isotherm studies were carried out to evaluate the effect of contact time, initial CPX concentration, adsorbent dosage, pH and temperature. The adsorbents were characterized by ATR-FTIR, N2 sorption, SEM and XRD, while several isotherm, kinetic and thermodynamic models were evaluated attempting to shed light on the adsorption mechanisms. CPX adsorption on both adsorbents was better described by Langmuir model, with an adsorption capacity of 112.36 mg/g for palygorskite and 11.79 mg/g for bauxite. Thermodynamics revealed the endothermic and the spontaneous character of the process, indicating chemisorption as the main adsorption mechanism for both adsorbents. The pseudo-second-order and the Elovich models fitted satisfactorily the adsorption onto bauxite, while adsorption onto palygorskite was well presented by Weber–Morris model, indicating that pore diffusion is also involved in the process. The adsorption capacity of both minerals decreased significantly after being used for several adsorption cycles and then almost completely recovered (regeneration efficiency was 99.6% and 98% for palygorskite and bauxite, respectively) inside a novel cold plasma microbubble reactor energized by high-voltage nanopulses, revealing the potential of these adsorbents to be reused. In addition to the regeneration of the adsorbents, the cold plasma completely eliminated the CPX transferred from the solid to the aqueous phase during the regeneration process. [ABSTRACT FROM AUTHOR]

Cold atmospheric plasma (CAP) has gaining potential, and very effective to curb or deactivate the various microorganisms such as bacteria and virus. Lately, the major outbreak SARS-CoV-2 infection has affected humanity largely with added complexity of its ability to mutate to variants such as Omicron. We have earlier shown the effectiveness of CAP on SARS-CoV-2 spike protein and, in this study, we have evaluated the effectiveness of CAP to deactivate Omicron. We studied the ability of the binding of Angiotensin converting Enzyme Protein (ACE2) protein to the plasma treated spike S1-S2 protein and spike Receptor binding domain (RBD) using Cold atmospheric plasma direct treatment as well as Plasma activated water (PAW). Results have shown the binding efficiency of Omicron spike protein to ACE2 decrease with increase in treatment time with both direct treatment and PAW as evidenced using spectroscopic techniques. The reactive species (RONS) play a major role in the efficient deactivation of the binding of ACE2 to the Omicron spike protein. Correspondingly, the comparison between the efficiency between direct treatment and PAW has also been discussed. [ABSTRACT FROM AUTHOR]

The present study investigates the mechanism of cold plasma modification (CP) of guar seed galactomannan on the structural, chemical, dietary fiber profile and the possibility to stabilize the orange juice. The cold plasma treatments were done at 170 and 230 V for 30 and 60 min and investigated for the modifications. The polar oxidative functionalities COOH- (283.36% rise) and OH- (16% rise) increased sequentially as a result of plasma-induced depolymerization with an increase in plasma voltage and time which was also supported by FTIR findings. The inclusion of COOH- reduced the pH from 7.09 ± 0.01 to a minimum of 4.96 ± 0.01. The cleavage of galactose side chains increased the free galactose content and reduced the M/G ratio from 2.38 ± 0.73 to 1.67 ± 0.19. The plasma etching phenomena reduced the average particle size to a minimum of 14.36 nm and is also seen in SEM. An increase in surface negative charges was shown with a decrease in zeta potential. The phenomenon of depolymerization, glycosidic cleavages at the side chains, and surface etching of cold plasma was exhibited with substantial evidence. Total dietary fiber was unaffected with an elevated soluble fiber content. Plasma treated guar gum has improved the stability of orange juice (rise in serum cloudiness with reduction in sedimentation and viscosity) without significant modifications in the quality (total soluble solids, pH, color). The obtained results demonstrate the CP interaction with guar gum and prove the potential of this green technology for the production of partially depolymerized guar gum. [ABSTRACT FROM AUTHOR]

This study investigates the relation between cold atmospheric pressure plasma (CAPP) effect on seeds and the plasma parameters. As a source of CAPP, the diffuse coplanar surface barrier discharge (DCSBD) generated in nitrogen, ambient air, and oxygen at atmospheric pressure was used. Results of germination and the level of DNA damage of soybean seeds (Glycine max L.) treated in plasma and plasma gaseous products showed that the most advantageous is the use of ambient air plasma treatment. The water contact angle (WCA) of samples treated directly in plasma was significantly smaller than that of samples treated with gaseous products. Using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), we did not observe significant changes between the spectra of individual samples, what indicates that there is no damage on the surface of the samples during the treatment, only the binding of polar groups. The method of optical emission spectroscopy (OES) and Fourier transform infrared spectroscopy (FTIR) were used to study the plasma parameters. The most radiant system observed in ambient air and nitrogen plasma is the second positive system of nitrogen N 2 C 3 ∏ u → B 3 ∏ g . FTIR measurements showed the presence of reactive oxygen and nitrogen species O3, NO2, N2O, NO, HNO2 depending on the working gas. Finally, it can be assumed that the positive effect of plasma on the seed is caused not only by the individual components of the plasma, but also by their synergistic effect, while the ratio of the individual active particles as well as the plasma exposure to the seeds are important. [ABSTRACT FROM AUTHOR]

Background: Plasma-activated water (PAW) is a solution created by exposing water to cold atmospheric plasma discharge, resulting in a biocidal agent with unique biochemical properties attributed to highly reactive oxygen and nitrogen species (RONS). Plasma-activated water (PAW) has been the subject of research for its potential in promoting seed germination. While it has shown promising results, the exact mechanism by which PAW promotes seed growth remains unclear. This study aims to investigate the role of PAW in promoting mung bean germination, including its effects on vitality improvement and the triggering of plant stress responses to promote crop growth. Through the utilization of next-generation sequencing, we aim to explore the interaction between the properties of PAW and gene expression in mung beans. By deciphering the nature of PAW and analyzing gene expression patterns, we hope to uncover the underlying mechanisms that govern their interaction. Results: The results revealed that nitrogen plasma-activated water (NPAW) treatment improves the vitality and hypocotyl length of mung beans and leads to a good overall growth state. Moreover, we identified numerous differentially expressed genes (DEGs), including genes related to stress responses, growth regulation, and metabolic processes, that were upregulated or downregulated in response to PAW treatment. As a result of APAW treatment, 168 genes were upregulated and 90 genes were downregulated. Furthermore, 179 genes were upregulated in the NPAW compared to 125 genes that were downregulated in the control group. Gene expression analysis revealed involvement in stress signaling and metabolic processes. Conclusions: PAW treatment can promote crop growth and serve as a reference for other seeds. This research provides insights into the regulatory mechanisms and benefits of PAW in sustainable agriculture. [ABSTRACT FROM AUTHOR]

The International Symposium on Plasma Chemistry (ISPC) is a biannual conference that was held in Kyoto, Japan for its 25th edition. The conference, which was originally scheduled for 2021 but postponed due to the COVID-19 pandemic, welcomed 563 attendees from 35 countries. A total of 465 oral and poster presentations were delivered, covering various scientific and application topics. The conference also awarded the Plasma Chemistry Award to Dr. Anthony Murphy and Dr. Francoise Massines for their lifetime achievements in the field. Additionally, the Young Investigator Awards and various medals were given to outstanding researchers. The conference proceedings are available online. [Extracted from the article]

This paper focuses on the use of an electro-optic (EO) probe for the spatially and temporally resolved characterization of the electric field (E-field) associated with guided ionization waves—or guided streamers—propagating at atmospheric pressure. An AC high-voltage power supply (6 kV at 18 kHz) is used to generate guided ionization waves in helium with a cold atmospheric pressure plasma jet device (APPJ). The capabilities of this electro-optic technique are investigated with and without the discharge. This innovative technology will use to carry out the optical polarimetric analysis of the APPJ with simultaneous real-time measurement of longitudinal and radial components of the electric field vector. Last but not least, an application-based case study of the ionization waves propagating and interacting with the EO probe—being a solid dielectric target—is also reported. The results will bring realistic information on the potential perturbation induced by the EO probe itself on the E-field characterization at the macroscopic scale. [ABSTRACT FROM AUTHOR]

The intensity of the interaction between a helium cold atmospheric plasma jet (CAPJ) and a dielectric surface or animal skin is compared in experiment and numerical simulation. A cold plasma jet at atmospheric pressure is generated by a sinusoidal or positive pulsed voltage with different pulse durations in optimal modes. The impact effect is estimated on the basis of measured and calculated currents, line intensities in the CAPJ spectrum and temperature fields. The measured CAPJ characteristics show that the pulsed voltage for the CAPJ excitation is preferable compared to the sinusoidal mode. Varying the pulse duration of the periodic pulsed voltage makes it possible to obtain the maximum current and electric field strength at the surface within the permissible temperature in the contact area of the CAPJ with the skin of mice (<42°C). It is shown that the results of the CAPJ study obtained in physical experiments using a dielectric plate are applicable for tumor-bearing mice treatment. [ABSTRACT FROM AUTHOR]

The grim situation of bacterial infection has undoubtedly become a major threat to human health. In the context of frequent use of antibiotics, a new bactericidal method is urgently needed to fight against drug-resistant bacteria caused by non-standard use of antibiotics. Cold atmospheric plasma (CAP) is composed of a variety of bactericidal species, which has excellent bactericidal effect on microbes. However, the mechanism of interaction between CAP and bacteria is not completely clear. In this paper, we summarize the mechanisms of bacterial killing by CAP in a systematic manner, discuss the responses of bacteria to CAP treatment that are considered to be related to tolerance and their underlying mechanisms, review the recent advances in bactericidal applications of CAP finally. This review indicates that CAP inhibition and tolerance of survival bacteria are a set of closely related mechanisms and suggests that there might be other mechanisms of tolerance to survival bacteria that had not been discovered yet. In conclusion, this review shows that CAP has complex and diverse bactericidal mechanisms, and has excellent bactericidal effect on bacteria at appropriate doses. Key points: • The bactericidal mechanism of CAP is complex and diverse. • There are few resistant bacteria but tolerant bacteria during CAP treatment. • There is excellent germicidal effect when CAP in combination with other disinfectants. [ABSTRACT FROM AUTHOR]

The main objective of this work was to design a large-scale cold atmospheric plasma brush (LSCAPB) that can produce a perfectly homogenous large area capable of producing plasma with a length of about 5 cm for studying the inactivation effect of plasma on Gram-positive and Gram-negative bacteria that commonly implicated in Food infections. Gram-positive (Listeria monocytogenes, Bacillus cereus) and Gram-negative (Salmonella typhi, Vibrio cholerae) bacteria with an initial population density of 1.5 × 108 CFU mL−1 were treated, and their survivability with plasma exposure was examined. The effect of plasma exposure in the reduction of bacteria population was investigated using OD600 absorbance, and changes in cell structure and the membrane were studied by scanning electron microscopy analysis. For applied voltage 25 kV and after 10 min the reduction of cold plasma treatment for S. typhi, V. cholerae, B. cereus, and L. monocytogenes were decreased from 1.5 × 108 to 0.3 × 102, 1.5 × 102, 0.6 × 103, and 0.7 × 105 CFU mL−1, respectively. Comet assay analysis was used for studying the effect of plasma exposure on DNA damage, and changes in chemical bonds were analyzed by FTIR analysis. So, the best destruction is obtained at the voltage of 25 kV for all types of bacteria. This study indicates that the inactivation effect of LSCAPB correlates with the kind of bacteria. We demonstrated LSCAPB can be one of the most efficient methods for the inactivation of different types of bacteria. [ABSTRACT FROM AUTHOR]

Using tissue engineering approaches is one of interesting strategies to repair cartilage injuries. This study reports the preparation of surface-modified electrospun polycaprolactone nanofibrous scaffolds with highly negatively-charged sulfated alginate as functional support for chondrogenic differentiation of mesenchymal stem cells. In this regard, polycaprolactone (PCL) nanofibers were fabricated by electrospinning, surface-activated by cold atmospheric plasma and further surface-modified with aqueous solutions of sulfated alginate. The scanning electron microscopy images showed the nanofibrous structure of electrospun PCL mats. The successful surface modification of PCL nanofibrous scaffolds with sulfated alginate was confirmed by the appearance of fingerprint region of mannuronic acid at 812 cm−1 in attenuated total reflectance Fourier transform infrared spectroscopy spectra. The cytocompatibility of the nanofibrous scaffolds for mesenchymal stem cells (MSCs) was confirmed using MTT assay. Reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemistry for type 2 COLLAGEN marker were conducted to confirm the chondrogenic differentiation of seeded MSCs on the surface of scaffolds. The expression of type 2 COLLAGEN by RT-PCR and immunocytochemistry analyses confirmed the chondrogenic differentiation of MSCs. Our results showed that sulfated alginate surface-modified PCL nanofibrous scaffold as an appropriate substrate for cell attachment and growth could promote the MSCs differentiate to chondrocytes. [ABSTRACT FROM AUTHOR]

The present study reports a significant combined antibacterial activity of Cichorium intybus L. (known as Chicory) natural extract with cold atmospheric-pressure argon plasma treatment against multi-drug resistant (MDR) Gram-negative bacteria. To detect reactive species that are generated in the argon plasma, optical emission spectra were recorded. The molecular bands were allocated to the hydroxyl radicals (OH) and neutral nitrogen molecules (N2). Moreover, the atomic lines form the emitted spectra were determined to argon atoms (Ar) and the oxygen atoms (O), respectively. The results revealed that Chicory extract treatment at a concentration of 0.043 g/ml reduced the metabolic activity of P. aeruginosa cells by 42%, while, a reduced metabolic activity of 50.6% was found for E. coli biofilms. Moreover, the combination of Chicory extract with 3 min Ar-plasma introduced a synergistic effect, so that it exhibited a significantly reduced metabolic activity of P. aeruginosa to 84.1%, and E. coli ones to 86.7%, respectively. The relationship between cell viability and membrane integrity of P. aeruginosa and E. coli biofilms treated with Chicory extract and argon plasma jet were also analyzed by CLSM. It was found that after the combined treatment, a noticeable membrane disruption was formed. Besides, it was concluded that E. coli biofilms showed a higher sensitivity to Ar-plasma than P. aeruginosa biofilm at longer plasma exposure times. This study suggests that the anti-biofilm therapy based on a combined effect of Chicory extract and cold argon plasma treatment can serve as a considerable green method for treatment of antimicrobial MDR bacteria. [ABSTRACT FROM AUTHOR]

Low-temperature plasma jets at atmospheric pressure generated by sinusoidal and positive pulsed voltages interact differently with the treated surface. In the experiment and in numerical simulations, we compare the operating modes of helium plasma jets for these types of operating voltages. The discharge current on the treated surface over time and the surface heating are studied for different discharge parameters acceptable for anticancer therapy. The intensity of the emission spectrum is analyzed to improve the effectiveness of the plasma jet. Surface heating is controlled in order to meet the safety conditions of plasma exposure to biological objects. For the case of pulsed voltage the effect of voltage pulse duration on the intensity of plasma-surface interaction is discussed. The results on cancer cells A549 and MCF-7 demonstrate the high efficiency of the cold plasma jet generated at found optimal modes. [ABSTRACT FROM AUTHOR]

Cold atmospheric pressure plasma (CAP) has been described as a novel technology with expanding applications in biomedicine and biotechnology. In the present study, we provide a mildly stressful condition using non-lethal doses of CAP (120, 180, and 240 s) and evaluate its potential benefits on the recombinant production of a model protein (enhanced green fluorescent protein (eGFP)) in yeast Pichia pastoris. The measured eGFP fluorescence augmented proportional to CAP exposure time. After 240 s treatment with CAP, the measured fluorescent intensity of culture supernatant (after 72 h) and results of real-time PCR (after 24 h) indicated an 84% and 76% increase in activity and related RNA concentration, respectively. Real-time analysis of a list of genes involved in oxidative stress response revealed a significant and durable improvement in their expression at five h and 24 h following CAP exposure. The improvement of the recombinant model protein production may be partly explained by the impact of the RONS on cellular constituents and altering the expression of specific stress genes. In conclusion, using CAP strategy may be considered a valuable strategy to improve recombinant protein production, and deciphering the molecular background mechanism could be inspiring in the reverse metabolic engineering of host cells. [ABSTRACT FROM AUTHOR]

There is a strong and ever-escalating need for sterilization tools that are effective against a broad range of pathogenic microorganisms. To address this issue, this study evaluates the inactivation potential of arc and pulsed spark plasma discharges on Pseudomonas aeruginosa, Staphylococcus aureus, Microsporum canis, Trichophyton mentagrophytes, and Candida albicans microorganisms. Our results show that the electrical discharge plasma systems are effective in the inactivation of pathogenic microorganisms. The inactivation of the considered strains was greatly affected by the type of microorganisms. Higher viability losses of the pathogenic strains were observed in bacterial strains than in the fungal strains. Moreover, in the case of fungal strains, the population of C. albicans was decreased the most, followed by Trichophyton mentagrophyte, while the population of Microsporum canis was decreased the least. Besides, the arc discharge system was compared with the pulsed spark discharge system. It can be obtained from the results that the pulsed spark discharge treatment successfully enhanced the reduction of the pathogenic cells more than the arc discharge treatment. The higher efficiency of the pulsed spark discharge is due to the generation of discharge streamers on the water surface. The SEM analyses showed that electrical discharge plasmas produced serious damage to pathogenic eukaryotic and prokaryotic microorganisms. Also, the plasma-induced changes in pH values and temperature values were measured. The pulsed spark discharge-treated samples have more significant changes in pH value while arc discharge-treated samples have larger temperature changes. [ABSTRACT FROM AUTHOR]

The effective medical applications of cold atmospheric pressure plasma jet (APPJ) have been reported by many researchers, including sterilization of liquid and solid surfaces, treatment of chronic wounds, treatment of cancer tumors, and blood clots. Therefore, in this study, we exposed Aporrectodea trapezoides and Eisenia fetida earthworms to APPJ discharge (0–30 s) to evaluate the impacts on regeneration of missed segments, apoptosis, lipid peroxidation (LPo), catalase activity (CAT), total antioxidant capacity (TAC), total proteins, and protein profile. Results showed APPJ induced significant effects on regeneration ability of earthworms after 20 and 30 s of exposure (p < 0.05). Atmospheric pressure plasma jet did not have significant effects on MDA content and TUNEL-positive cells, but this effect was significant for TAC and CAT in both species (p < 0.05). In conclusion, the present study revealed for the first time that regeneration of missed segments in earthworms can be stimulated by plasma treatment. [ABSTRACT FROM AUTHOR]