Szabolcs Tallósy - Academia.edu (original) (raw)

Papers by Szabolcs Tallósy

Scientific reports, Mar 26, 2024

Sepsis is accompanied by a less-known mismatch between hemodynamics and mitochondrial respiration... more Sepsis is accompanied by a less-known mismatch between hemodynamics and mitochondrial respiration. We aimed to characterize the relationship and time dependency of microcirculatory and mitochondrial functions in a rodent model of intraabdominal sepsis. Fecal peritonitis was induced in rats, and multi-organ failure (MOF) was evaluated 12, 16, 20, 24 or 28 h later (n = 8/group, each) using rat-specific organ failure assessment (ROFA) scores. Ileal microcirculation (proportion of perfused microvessels (PPV), microvascular flow index (MFI) and heterogeneity index (HI)) was monitored by intravital video microscopy, and mitochondrial respiration (OxPhos) and outer membrane (mtOM) damage were measured with high-resolution respirometry. MOF progression was evidenced by increased ROFA scores; microcirculatory parameters followed a parallel time course from the 16th to 28th h. Mitochondrial dysfunction commenced with a 4-h time lag with signs of mtOM damage, which correlated significantly with PPV, while no correlation was found between HI and OxPhos. High diagnostic value was demonstrated for PPV, mtOM damage and lactate levels for predicting MOF. Our findings indicate insufficient splanchnic microcirculation to be a possible predictor for MOF that develops before the start of mitochondrial dysfunction. The adequate subcellular compensatory capacity suggests the presence of mitochondrial subpopulations with differing sensitivity to septic insults.

Chemical Engineering & Technology, Feb 11, 2023

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Zenodo (CERN European Organization for Nuclear Research), Jul 5, 2014

Purification of polluted water and air is a major issue nowadays and calls for urgent solutions g... more Purification of polluted water and air is a major issue nowadays and calls for urgent solutions globally. Hence, it is important to find well working, and energy efficient alternatives besides or instead of the regular air and water treatment technologies to remove harmful chemical compounds and pathogens, mold etc. from our environment by using the natural alternative energy sources such as sunlight. Visible-light responsive Ag-TiO2 was prepared by reduction of AgNO3 on the surface of TiO2 (wt%Ag = 0.5%). The formed Ag nanoparticles (NPs) had a particle size of 5-15 nm and showed strong Vis-light absorbance in the 400 – 500 nm wavelength range of the UV-Vis spectrum with a maximum at 455 nm. Light absorption of TiO2 is limited to the UV region (≤ 400 nm) because of its narrow band gap (Eg = 3.2 eV for anatase and 3.0 eV for rutile) which is not efficient considering to rely on solar energy solely to trigger the photocatalytic mechanism. Plasmonic noble metal NPs such as silver or gold, deposited in a small amount on TiO2 extends the light absorption of TiO2 into the Vis range. Moreover, they promote the electron-hole separation of the photocatalyst by acting as electron traps therefore significantly can increase the photocatalytic activity of TiO2 under UV or Vis light. Ag-TiO2 photocatalyst and TiO2 were embedded in [poly(ethyl acrylateco-methyl methacrylate; p(EA-co-MMA)] co-polymer to attain mechanically stable, photocatalytically active nanocomposite films. Ethanol was chosen as a model compound of VOCs and the degradation of ethanol vapour was followed on the composite films under UV-Vis light irradiation in a closed flat film reactor covered with quartz glass on the top to transmit the whole range of light emitted from the light source (Lighttech, Hungary, λ ≤ 254 nm, λmax=435 nm). The concentration of ethanol and intermediate products were monitored by GC-FID and -TCD. Antibacterial activity of the composite films was demonstrated by microbial tests using Methicillin resistant Staphylococcus aureus bacte [...]

Applied Clay Science

Layered double oxide (LDO) photocatalyst microparticles were synthetized with special radial lame... more Layered double oxide (LDO) photocatalyst microparticles were synthetized with special radial lamellar orientation. We presented that the 25.31 ± 2.34 mm LDO particles with rough surface can incorporated in fluoropolymer solution and resulted a composite layer with dual superhydrophobic and photocatalytic properties with high bacterial adhesion and inactivation ability. Next the LDO content in the composite layers were systematically increased (0, 20, 40, 60, 80 and 100 wt.% LDO) which facilitated the surface adhesion of bacteria by electrostatic interactions. The structure of the initial LDO and LDO/fluoropolymer composites was verified by small angle X-ray scattering (SAXS), XRD and SEM measurements. We showed that the surface roughness and hydrophobicity increase with increasing LDO loading. At 80/20 wt.% LDO/fluoropolymer ratio the apparent surface energy was low enough to obtain a superhydrophobic surface (= 156.3° and = 2.7 mJ/m 2). The bacterial adhesion extent on LDO/fluoropolymer composite layers increases with increasing LDO content because the adhesion takes place preferentially to LDO lamellae. The reason for this pronounced adhesion of negatively charged and hydrophilic bacteria onto positively charged and hydrophilic LDO surfaces is the electrostatic attraction between oppositely charged surfaces. The bacterial adhesion was detected by scanning electron and fluorescence microscopy and crystal violet staining assay. Finally, the adhered bacteria were inactivated by the LED-light illumination due to photoreactivity of LDO particles containing 12 wt.% of ZnO phase. Response to Reviewers: we would like to thank the Reviewer for his very positive evaluation of out manuscript, and for the insightful comments which truly improved the quality of the manuscript! Please find our detailed answers to the suggestions and comments of the Editor and Reviewer. The modifications are rooted in the comments. Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation Revision Notes_Response to Reviewers Click here to access/download;Revision Notes_Response to Reviewers;Revision Notes_18_May_2022_highlighted.docx Regarding to the suggestion of the Reviewer#1 Fig. 2 was corrected, the composition of the samples was indicated above each point of the graph.

Frontiers in Medicine

IntroductionSepsis can lead to organ dysfunctions with disturbed oxygen dynamics and life-threate... more IntroductionSepsis can lead to organ dysfunctions with disturbed oxygen dynamics and life-threatening consequences. Since the results of organ-protective treatments cannot always be transferred from laboratory models into human therapies, increasing the translational potential of preclinical settings is an important goal. Our aim was to develop a standardized research protocol, where the progression of sepsis-related events can be characterized reproducibly in model experiments within clinically-relevant time frames.MethodsPeritonitis was induced in anesthetized minipigs injected intraperitoneally with autofeces inoculum (n = 27) or with saline (sham operation; n = 9). The microbial colony-forming units (CFUs) in the inoculum were retrospectively determined. After awakening, clinically relevant supportive therapies were conducted. Nineteen inoculated animals developed sepsis without a fulminant reaction. Sixteen hours later, these animals were re-anesthetized for invasive monitoring...

Journal of Advanced Oxidation Technologies, 2012

Phosphate and silver co-functionalized TiO 2 catalysts were prepared by varying amount of silver ... more Phosphate and silver co-functionalized TiO 2 catalysts were prepared by varying amount of silver (0-1 wt.%) with constant phosphate content (0.25 wt.%). Two methods, the well-know photodeposition and a new simple method, i.e. heterocoagulation, are presented for preparing Ag-TiO 2 and the optical, photochemical and photobiological properties of the different samples have been compared. Due to the silver modification, the photocatalysts showed a new Plasmon resonance peak at  max = 455 nm. The photocatalytic efficiencies of the new photocatalysts were studied under UV-A/visible (≥ 360 nm) irradiation. Mechanically stable hydrophilic poly(EA-coMMA) and hydrophobic poly(Bi.A-co-Ech.) based composite films were prepared by spray coating technique. The photocatalytic efficiencies decreased only by~15% on the hydrophilic and~63% on the hydrophobic polymer compared to the reference pure photocatalyst films. The antibacterial activity of the films was also studied under visible light (≥ 400 nm) irradiation. Methicillin resistant Staphylococcus aureus (MRSA) was used as test bacterium. The best antibacterial activity (90% of bacteria destruction in 15 minutes) could be observed on the Ag-TiO 2 /p(EA-coMMA) film.

Journal of Advanced Oxidation Technologies, 2014

Silver functionalized TiO 2 /poly(etyl-acrylate co methyl-methacrylate) nanohybrid films were pro... more Silver functionalized TiO 2 /poly(etyl-acrylate co methyl-methacrylate) nanohybrid films were proved to inactivate nosocomial bacteria. The films were prepared on glass plates by spray coating technique and their thickness were 1.48±0.1 µm. During photocatalysis, the films were illuminated with visible LED-light source (λ = 405 nm). The optical and photooxidation properties of prepared nanocomposite films were characterized by diffuse reflectance measurements and the photocatalytic properties were tested in ethanol photooxidation monitored by gas-chromatography experiments. The photocatalytic activity of the nanohybrid films were tested under visible light illumination against bacteria causing nosocomial infections, such as methicillin resistant Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa and Acinetobacter baumannii. The investigation of the antibacterial activity of the silver functionalized TiO 2 was carried out by measuring the survival ratio of the original amount of the bacteria on the nutrient agar plate. To verify the photooxidation effect of the reactive films, parallel experiments were carried out without any light source. All of the investigated bacteria were inactivated on the surface of the nanohybrid films within 120 minutes of LED-light illumination.

Catalysis Today, 2017

In the search for highly active and stable photocatalysts, significant efforts are devoted to fin... more In the search for highly active and stable photocatalysts, significant efforts are devoted to find both new materials and innovative synthetic methods. In this study, an environmentally friendly and sustainable approach, dry reactive milling, was employed to synthesize two different semiconducting oxide nanomaterials, namely TiO 2 and ZnO using polysaccharides as sacrificial templates. The as synthesized nanomaterials were characterized by powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, diffuse reflection UV-vis and Raman spectroscopy, and N 2 adsorption tests. Their photocatalytic activity was tested in ethanol degradation, followed by gas chromatographic analysis. Photoelectrochemical measurements were performed to assess the optoelectronic properties and the antimicrobial activity of these photocatalysts was also tested under visible light irradiation. Overall, we found that the performance of the synthesized nanomaterials was comparable to the benchmark P25 EVONIK titania, with ZnO exhibiting a remarkably superior antibacterial activity against E. coli.

Applied Surface Science, 2016

The aim of this study was to develop photoreactive surface coatings, possessing antibacterial pro... more The aim of this study was to develop photoreactive surface coatings, possessing antibacterial proper ties and can be activated under visible light illumination (%max=405nm) using LED-light source. The photocatalytically active titanium dioxide (TiO2) was functionalized with silver nanoparticles (Ag NPs) and immobilized in polyacrylate based nanohybrid thin film in order to facilitate visible light activity (-^Ag/TiO2,maX = 500 nm). First, the photocatalytic activity was modelled by following ethanol vapor degra dation. The plasmonic functionalization resulted in 15% enhancement of the activity compared to pure TiO2. The photoreactive antimicrobial (5log reduction of cfu in 2h) surface coatings are able to inac tivate clinically relevant pathogen strains (methicillin resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa) within short time (60-120 min) due to the formed and quantified reactive oxy gen species (ROS). The existence of electrostatic interactions between the negatively charged bacteria (from-0.89 to-3.19 ^eq/109 cfu) and positively charged photocatalyst particles (in the range of +0.38 and +12.3meq/100g) was also proven by charge titration measurements. The surface inactivation of the bacteria and the photocatalytic degradation of the cell wall component were also confirmed by fluo rescence and transmission electron microscopic observations, respectively. According to the results an effective sterilizing system and prevention strategy can be developed and carried out against dangerous microorganisms in health care.

Langmuir : the ACS journal of surfaces and colloids, Jan 24, 2015

Aqueous suspensions of spherical ZnMgAl-layered double hydroxides [LDH(sph)] and antibacterial si... more Aqueous suspensions of spherical ZnMgAl-layered double hydroxides [LDH(sph)] and antibacterial silver nanoparticles (AgNPs) deposited on the lamellae of montmorillonite were used for the synthesis, of composites, which behave like coherent gels at low pH (<~4.5) and incoherent sols at higher pH values (>~4.5). The composition of the composite was chosen as LDH(sph)/Ag°-montm = 25:75 wt% in order to ensure a sol-gel transition that can also be characterised by viscometry. This pH-sensitive heterocoagulated system - consisting of oppositely charged colloid particles - was suitable for the release of antimicrobial AgNPs immobilized on the clay lamellae via pH-controlled gel-sol transition. The heterocoagulation process was also characterised by surface charge titration measurements. Spherical LDH/Ag°-montmorillonite composite samples were identified by X-ray diffraction (XRD) measurements. The morphological properties of the composites were studied, and the presence of the hetero...

Environmental Science and Pollution Research, 2014

Nanosilver-modified TiO2 and ZnO photocatalysts were studied against methicillin-resistant Staphy... more Nanosilver-modified TiO2 and ZnO photocatalysts were studied against methicillin-resistant Staphylococcus aureus on the surface and against naturally occurring airborne microorganisms. The photocatalysts/polymer nanohybrid films were prepared by spray coating technique on the surface of glass plates and on the inner surface of the reactive light source. The photoreactive surfaces were activated with visible light emitting LED light at λ = 405 nm. The optical properties of the prepared photocatalyst/polymer nanohybrid films were characterized by diffuse reflectance measurements. The photocatalytic properties were verified with the degradation of ethanol by gas chromatography measurements. The destruction of the bacterial cell wall component was examined with transmission electron microscope. The antibacterial effect of the photocatalyst/polymer nanohybrid films was tested with different methods and with the associated standard ISO 27447:2009. With the photoreactive coatings, an extensive disinfectant film was developed and successfully prepared. The cell wall component of S. aureus was degraded after 1 h of illumination. The antibacterial effect of the nanohybrid films has been proven by measuring the decrease of the number of methicillin-resistant S. aureus on the surface and in the air as the function of illumination time. The photocatalyst/polymer nanohybrid films could inactivate 99.9 % of the investigated bacteria on different thin films after 2 h of illumination with visible light source. The reactive light source with the inner-coated photocatalyst could kill 96 % of naturally occurring airborne microorganisms after 48 h of visible light illumination in indoor air sample. The TEM results and the microbiological measurements were completed with toxicity tests carried out with Vibrio fischeri bioluminescence bacterium.

International Journal of Molecular Sciences, May 3, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Frontiers in Cell and Developmental Biology

A number of studies have demonstrated explicit bioactivity for exogenous methane (CH4), even thou... more A number of studies have demonstrated explicit bioactivity for exogenous methane (CH4), even though it is conventionally considered as physiologically inert. Other reports cited in this review have demonstrated that inhaled, normoxic air-CH4 mixtures can modulate the in vivo pathways involved in oxidative and nitrosative stress responses and key events of mitochondrial respiration and apoptosis. The overview is divided into two parts, the first being devoted to a brief review of the effects of biologically important gases in the context of hypoxia, while the second part deals with CH4 bioactivity. Finally, the consequence of exogenous, normoxic CH4 administration is discussed under experimental hypoxia- or ischaemia-linked conditions and in interactions between CH4 and other biological gases, with a special emphasis on its versatile effects demonstrated in pulmonary pathologies.

Tantargy celja A tantargy elvart kimeneti kovetelmenyei (Kompetenciamerő lap) Szamonkeres modja A... more Tantargy celja A tantargy elvart kimeneti kovetelmenyei (Kompetenciamerő lap) Szamonkeres modja A kepzes sikeres elvegzesenek feltetelei A tanulasi eredmenyek ertekelese A kollokviumjegy szamitasa A tanulasi eredmenyek elereset tamogato modszerek: Ajanlott felkeszulesi lepesek: ad 1. Az osszevont gyakorlatok latogatasa ad 2. A gyakorlatok latogatasa ad 3. Videok a Coospace-en (wmw) ad 4. A gyakorlati vizsga ertekelesi szempontjainak attekintese (a Melleklet tartalmazza) ad. 5. Szemelyes konzultacio lehetősege az oktatokkal