Cold atmospheric plasma induced genotoxicity and cytotoxicity in esophageal cancer cells

Molecular Biology Reports - In this paper, we studied the functional effects of cold atmospheric plasma (CAP) on the esophageal cancer cell line (KYSE-30) by direct and indirect treatment and...     

Cold atmospheric plasma applications in dermatology: A systematic review

Cold atmospheric plasma (CAP) applications can potentially lead to effective therapy for numerous skin diseases. Our aim is to systematically review the available data and map the use of CAP in dermatology. PubMed, Embase and Web of science were explored before 2020 for studies regarding the use of CAP in dermatology. A total of 166 studies were finally included. 74.1% of these studies used indirect CAP sources. Most studies used plasma jet (67.5%). Argon was the mostly used working gas (48.2%). Plasma application itself could be direct (89.2%) and indirect (16.3%). The proportion of studies with in vivo results remained 57.2%, of which most concerned direct plasma treatment (97.9%). Analyses performed indicate that CAP has been beneficial in many skin disorders. While, most CAP applications were focused on wound healing and melanoma treatment. This study provides a brief overview of CAP sources and relative medical applications in dermatology.     

Cold adaptation of microorganisms

Psychrophilic and psychrotrophic microorganisms are important in global ecology as a large proportion of our planet is cold (below 5 degrees C); they are responsible for the spoilage of chilled food and they also have potential uses in low-temperature biotechnological processes. Psychrophiles and psychrotrophs are both capable of growing at or close to zero, but the optimum and upper temperature limits for growth are lower for psychrophiles compared with psychrotrophs. Psychrophiles are more often isolated from permanently cold habitats, whereas psychrotrophs tend to dominate those environments that undergo thermal fluctuations. The molecular basis of psychrophily is reviewed in terms of biochemical mechanisms. The lower growth temperature limit is fixed by the freezing properties of dilute aqueous solutions inside and outside the cell. In contrast, the ability of psychrophiles and psychrotrophs to grow at low, but not moderate, temperatures depends on adaptive changes in cellular proteins and lipids. Changes in proteins are genotypic, and are related to the properties of enzymes and translation systems, whereas changes in lipids are genotypic or phenotypic and are important in regulating membrane fluidity and permeability. The ability to adapt their solute uptake systems through membrane lipid modulation may distinguish psychrophiles from psychrotrophs. The upper growth temperature limit can result from the inactivation of a single enzyme type or system, including protein synthesis or energy generation.     

Cold atmospheric plasma jet effects on V79-4 cells

The effects of cold plasmas are due to charged particles, reactive oxygen species (ROS), reactive nitrogen species (RNS), UV photons, and intense electric field. In order to obtain a more efficient action on mammalian cells (useful for cancer therapy), we used in our studies chemically activated cold plasma (He and O2 gas mixture). V79-4 cells were exposed to plasma jet for different time periods (30, 60, 90, 120 and 150s), using different combinations of helium and oxygen inputs (He:2.5l/min + 02:12.5ml/min; He:2.51/min + O2:25ml/min; He:2.51/min + O2:37.5 ml/min). Using MTT test we demonstrated that plasma jet induced cell viability decrease in all cases. The effect of chemically activated cold plasma--apoptosis or necrosis--depends on gas mixture and treatment period. Taking into account that ROS density in cell microenvironment is related to O2 percent in the gas mixture and treatment period, we can presume that cell death is due to ROS produced in plasma jet.     

Origin of spores of anaerobic microorganisms in milk

Summary Samples from silage, hay, milk, air, and faeces were taken at 25 farms in mid-Sweden, farms with different hygienic standards of milk-production being chosen.The correlation between fodder and milk-quality was investigated. The investigation was limited to the transfer of spores of anaerobes to the milk during feeding with silage of various qualities.The role of grassland fodders other than silage in spore-infection of milk is discussed.These studies are still in progress. We are indebted to the Swedish Foundation: Fonden för främjande av forsknings- och försöksverksamheten på jordbrukets område for generous financial support. We also gratefully acknowledge the encouraging interest and support of Professor R. Nilsson.     

Contact-free inactivation of Candida albicans biofilms by cold atmospheric air plasma

Candida albicans is one of the main species able to form a biofilm on almost any surface, causing both skin and superficial mucosal infections. The worldwide increase in antifungal resistance has led to a decrease in the efficacy of standard therapies, prolonging treatment time and increasing health care costs. Therefore, the aim of this work was to demonstrate the applicability of atmospheric plasma at room temperature for inactivating C. albicans growing in biofilms without thermally damaging heat-sensitive materials. This so-called cold atmospheric plasma is produced by applying high voltage to accelerate electrons, which ionize the surrounding air, leading to the production of charged particles, reactive species, and photons. A newly developed plasma device was used, which exhibits a large plasma-generating surface area of 9 by 13 cm (117 cm(2)). Different time points were selected to achieve an optimum inactivation efficacy range of ≥3 log(10) to 5 log(10) reduction in CFU per milliliter, and the results were compared with those of 70% ethanol. The results obtained show that contact-free antifungal inactivation of Candida biofilms by cold atmospheric plasma is a promising tool for disinfection of surfaces (and items) in both health care settings and the food industry, where ethanol disinfection should be avoided.     

The activity of p-methoxybenzylisothiocyanate against Neisseria gonorrhoeae,Haemophilus ducreyi,and other microorganisms

p-Methoxybenzylisothiocyanate was isolated from Lepidium bonariense and found to be responsible for the plants antimicrobial and STD activity. MIC determinations were conducted for p-methoxybenzylisothiocyanate on Haemophilus ducreyi, Neisseria gonorrheae, Candida albicans, Bacillus subtilus, Micrococcus luteus, Staphylococcus aureus, Enterobacter sp., Escherichia coli, Klebsiella pneumoniae, and Psuedomanas aeruginosa. An in vitro cellular toxicity assay showed that at 100 microM (17,9 microg/mL) p-methoxybenzylisothiocyanate is not toxic to living cells.     

Cold atmospheric pressure plasma causes protein denaturation and endoplasmic reticulum stress in Saccharomyces cerevisiae

Applied Microbiology and Biotechnology - Cold atmospheric pressure plasma (CAP) does not cause thermal damage or generate toxic residues; hence, it is projected as an alternative agent for...     

Cold atmospheric plasma ameliorates imiquimod-induced psoriasiform dermatitis in mice by mediating antiproliferative effects

Psoriasis is a chronic hyperproliferative skin disease characterised by excessive growth of keratinocytes. Indeed, inducing keratinocyte apoptosis is a key mechanism responsible for psoriatic plaques clearance following some important existing therapies, which display pro-oxidant activity. Cold atmospheric plasma (CAP), acting as a tuneable source of reactive oxygen and nitrogen species (RONS), can controllably transfer RONS to the cellular environment, deliver antiproliferative RONS concentrations and exert antiproliferative and proapoptotic effects. This study was undertaken to evaluate the therapeutic potential of CAP in psoriasis. We used cell models of psoriasis-like inflammation by adding lipopolysaccharide (LPS) or tumour necrosis factor alpha (TNF-α) to HaCaT keratinocytes. Indirect plasma, plasma-activated medium (PAM), was administered to HaCaT cells. Atmospheric pressure plasma jet (APPJ) was applied directly to imiquimod (IMQ)-induced psoriasiform dermatitis in mice. The results showed that PAM induced an increase in intracellular ROS and caused keratinocyte apoptosis. Moreover, cells under inflammation showed lesser viability and larger apoptosis rate. With repeated administration of APPJ, psoriasiform lesions showed ameliorated morphological manifestation and reduced epidermal proliferation. Overall, this study supports that CAP holds good potential in psoriasis treatment.     

Understanding atmospheric intercontinental dispersal of harmful microorganisms

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An analysis of vacuum effects in the sterilization of microorganisms

Summary By using the thermodynamic formulation of the absolute reaction-rate theory, variations in pressure can be incorporated in a rational model for dry-heat sterilization of microorganisms. Coupling this model to observations, a V value of 15 to 651/mole is estimated for the sterilizing reaction. The theoretical V for DNA is about 71/mole.This work was conducted under Contract No. W-12, 853, NASA Headquarters, Washington, D. C.     

Cellulase-free xylanases from Bacillus and other microorganisms

Xylanases are used mainly in the pulp and paper industries for the pretreatment of Kraft pulp prior to bleaching to minimize use of chlorine, the conventional bleaching agent. This application has great potential as an environmentally safe method. Hydrolysis by xylanases of relocated and reprecipitated xylan on the surface of cellulose fibres formed during Kraft cooking facilitates the removal of lignin by increasing permeability to oxidising agents. Most of the xylanases reported in the literature contained significant cellulolytic activity, which make them less suitable for pulp and paper industries. The need for large quantities of xylanases which would be stable at higher temperatures and pH values and free of cellulase activity has necessitated a search for novel enzymes. We have isolated and characterised several xylanase-producing cultures, one of which (an alkalophilic Bacillus SSP-34) produced more than 100 IU ml(-1) of xylanase activity. The SSP-34 xylanases have optimum activity at 50 degrees C in a pH range 6-8, with only small amounts of cellulolytic activity (CMCase (0.4 IU ml(-1), pH 7), FPase (0.2 IU ml(-1), pH 7) and no activity at pH 9).     

Papers of interest in other journals

G. M. Friedman and W. E. Krumbein (eds.), Hypersaline Ecosystems, The Gavish Sabkha. Ecological Studies. Vol. 53. Springer‐Verlag New York, Inc., New York, 1985. 500 pp. (illus.), $98.00.