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The subject of the research presented in this paper was the evaluation of the technology of surface preparation of steel samples in terms of anti-adhesion and mechanical properties through the use of PFA coatings. Such coatings are used in many industries, e.g. in the manufacture and operation of metal moulds used, for example, in the production of resinous components. The specimens used in the study, which represented the surface of the moulds, were made from DC01 sheet. Six variants of release coating technology were used, differing in the number of technological operations and parameters. In the final stage, appropriate test methods were used to assess the energy properties of the coatings produced, the mechanical properties in terms of deformation of the supporting structure and the mechanical properties in terms of the effects on the coating itself. The scope of the research made it possible to determine the main properties that the manufactured coatings have in terms of their future practical applications. The results obtained for the surface free energy determined from the measurement of the surface wetting angle, the mechanical properties obtained from the three-point bending test and the evaluation of the surface quality of the coatings subjected to compressive and tensile deformations in the bending test, as well as the functional properties of the coatings in terms of their durability and adhesion determined in scratch tests, showed that the best characteristics were obtained for variant 6. This variant consisted of sequentially, after the initial stage, applying a primer layer and drying it for 15 minutes at 250°C, applying a PFA layer to the component at 150°C and then drying it for 15 minutes at 200°C and curing it for 20 minutes at 380°C. An additional layer of PFA was then applied and dried for 15 minutes at 200°C and cured for 20 minutes at 340°C. In addition, a long annealing for 3 hours at 340°C was applied in a given variant.

The subject of the research presented in this paper was the evaluation of the technology of surface preparation of steel samples in terms of anti-adhesion and mechanical properties through the use of PFA coatings. Such coatings are used in many industries, e.g. in the manufacture and operation of metal moulds used, for example, in the production of resinous components. The specimens used in the study, which represented the surface of the moulds, were made from DC01 sheet. Six variants of release coating technology were used, differing in the number of technological operations and parameters. In the final stage, appropriate test methods were used to assess the energy properties of the coatings produced, the mechanical properties in terms of deformation of the supporting structure and the mechanical properties in terms of the effects on the coating itself. The scope of the research made it possible to determine the main properties that the manufactured coatings have in terms of their future practical applications. The results obtained for the surface free energy determined from the measurement of the surface wetting angle, the mechanical properties obtained from the three-point bending test and the evaluation of the surface quality of the coatings subjected to compressive and tensile deformations in the bending test, as well as the functional properties of the coatings in terms of their durability and adhesion determined in scratch tests, showed that the best characteristics were obtained for variant 6. This variant consisted of sequentially, after the initial stage, applying a primer layer and drying it for 15 minutes at 250 °C, applying a PFA layer to the component at 150 °C and then drying it for 15 minutes at 200 °C and curing it for 20 minutes at 380 °C. An additional layer of PFA was then applied and dried for 15 minutes at 200 °C and cured for 20 minutes at 340 °C. In addition, a long annealing for 3 hours at 340 °C was applied in a given variant. [ABSTRACT FROM AUTHOR]

Adhesion of bacteria on biomedical implant surfaces is a prerequisite for biofilm formation, which may increase the chances of infection and chronic inflammation. In this study, we employed a novel electrospray-based technique to develop an antibacterial surface by efficiently depositing silica homogeneously onto polyethylene terephthalate (PET) film to achieve hydrophobic and anti-adhesive properties. We evaluated its potential application in inhibiting bacterial adhesion using both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria. These silica-deposited PET surfaces could provide hydrophobic surfaces with a water contact angle greater than 120° as well as increased surface roughness (root mean square roughness value of 82.50 ± 16.22 nm and average roughness value of 65.15 ± 15.26 nm) that could significantly reduce bacterial adhesion by approximately 66.30% and 64.09% for E. coli and S. aureus, respectively, compared with those on plain PET surfaces. Furthermore, we observed that silica-deposited PET surfaces showed no detrimental effects on cell viability in human dermal fibroblasts, as confirmed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide and live/dead assays. Taken together, such approaches that are easy to synthesize, cost effective, and efficient, and could provide innovative strategies for preventing bacterial adhesion on biomedical implant surfaces in the clinical setting.

Water-born flower-like nanostructures have been produced via electrospinning of an innovative bicomponent polymeric solution of cross-linkable amino-functional polysiloxane (X-AFPs) resin and polyvinyl alcohol (PVA) in a special condition, after an after-washing process. It is the first report on production of a resin-based flower-like nanostructure as well as a siliconic flower-like nanostructure. It is also a well-engineered water-based green technique. An interesting mechanism has been proposed according to the SEM outcomes as well as the principles of electrospinning. The paper gives an explanation of how some physicochemical phenomena such as specific interactions among the polymeric components as well as high-level differences in terms of electrical charge density, viscosity and elasticity can direct the formation of these amazing structures. Accordingly, this research can be considered as a key major guideline to develop other polymeric flower-like nanostructures and their associated cutting-edge applications. Developing an anti-adhesive membrane was also followed in this research. A super-hydrophobic feature was achieved on the post-treated flower-like structures with a hydrophobic X-AFPs layer, after elimination of the PVA residue. Cytocompatibility as well as anti-adhesive properties of the treated flower-like structures have been assayed and perfectly confirmed through an in vitro study on a highly adherent cell type in a high cell seeding concentration. Accordingly, these three dimensional multiple-scale flower-like nanostructures can be offered for a wide-range of biomedical applications especially for anti-adhesive requirements such as cardiovascular applications and/or controlled cell response approaches. [ABSTRACT FROM AUTHOR]

Nine strains of Lactiplantibacillus plantarum and one strain of Lacticaseibacillus paracasei that were recently isolated from prickly pears, fresh figs and blackberries, which are traditionally and largely consumed fruits in Kabylia (north of Algeria), were studied here for their antagonism and antioxidant properties as well as for production of exopolysaccharides. With respect to their inhibitory properties, these strains were tested against three food representative pathogens including Escherichia coli ATCC 8739, Staphylococcus aureus 2S6 and Listeria monocytogenes 162. The antagonism of these pathogens was attributable to lactic acid production, present in the cell free supernatant, at concentrations ranging from 9 to 16.74 g/L. The anti-adhesive properties observed on polystyrene or eukaryotic Caco-2 cells were exerted in a strain dependent-manner. Indeed, the scores obtained ranged from 27% to 75% for S. aureus 2S6, 54% to 95% for L. monocytogenes 162, and 50% to 97% for E. coli ATCC 8739. The co-aggregation of these Lactobacillus strains with the aforementioned target bacteria appeared to be exerted in a strain-dependent manner, with noticeably the upmost rate for Lb. paracasei FB1 on S. aureus 2S6. Interestingly, these novel Lactobacillus strains were able to produce a large amount (315.55 to 483.22 mg/L) of exopolysaccharides, and showed a significant scavenging activity on the 2,2-di-phényl-2-picrylhydrazyle (DPPH) synthetic free radical with rates of 51% to 56%. Of note, the highest antioxidant activity was observed for Lb. paracasei FB1 using the culture supernatants, intact cells or the intracellular extract. The statistical analysis of these data using the principal component analysis (ACP) enabled us to establish three distinct clusters with potential applications as bioprotective and/or probiotic agents, following further evaluation.

Biofilm, naturally formed by microorganisms as integrated surface-bound communities, is one of the reasons for the development of antimicrobial resistance. Haemophilus spp. are common and representative opportunistic Gram-negative rods forming from the upper respiratory tract microbiota. The aim of this paper was to evaluate the influence of thiazolidine-2,4-dionebased azolidine and chlorophenylthiosemicarbazone hybrids against both planktonic and biofilm-forming Haemophilus spp. cells. The in vitro activity against planktonic and biofilm-forming cells of the tested compounds were evaluated by using the broth microdilution method. These activities were detected against reference and clinical strains of Haemophilus spp. on the basis of MICs (minimal inhibitory concentrations) and MBICs (minimal biofilm inhibitory concentrations). In addition, anti-adhesive properties of these compounds were examined. The target compounds showed potential activity against planktonic cells with MIC = 62.5–500 mg/L and biofilm-forming cells with MBIC = 62.5–1000 mg/L. The observed anti-adhesive properties of the tested compounds were reversible during long-term incubation in a lower concentration of compounds.

Objectives: To investigate the efficacy of chitosan-dextran hydrogel (CDH) in preventing postoperative adhesions between the tympanic membrane (TM) and intratympanic structures, and to evaluate its ototoxicity in an animal study.Methods: In the first step, ototoxicity was evaluated with 7 male albino guinea pigs (GPs) via auditory brainstem responses (ABR) before and 4 weeks after unilateral intratympanic injection of CDH and saline solution contralaterally. In the second step, 12 GPs underwent bilateral ear surgery. The middle ear (ME) mucosa was abraded, and the cavity was filled with CDH on one side and packed with Gelfoam on the contralateral side. A control group of 6 GPs underwent the same procedure except that no material was applied in the ME. The animals were euthanized at the end of the 7th week, and otomicroscopic findings were noted and the temporal bones harvested for the histologic examination. The findings were scored and compared.Results: There was no statistically significant difference between the pre- and postoperative ABR thresholds. In the otomicroscopic findings, the most prominent difference between the two groups was the presence of retraction of the TM in the Gelfoam group. The histopathologic findings revealed a higher degree of inflammation in the Gelfoam group compared with the CDH group.Conclusion: This study demonstrated that CDH has no ototoxic effects in GPs. Its use as an ME packing material revealed significantly less TM retraction and inflammatory reaction compared with Gelfoam. [ABSTRACT FROM AUTHOR]

Highlights: [•] We modified titanium surfaces by ulvans polysaccharide. [•] We characterized modifications by XPS, AFM and contact angle. [•] Ulvans on titanium surface strongly decreased by about 90% the adhesion of Pseudomonas aeruginosa. [•] Polysaccharide also inhibited the bacterial spreading on the surface. [ABSTRACT FROM AUTHOR]

A series of plasma-mediated coatings, containing silver nanoparticles embedded in an organosilicon or silica-like matrix, were deposited onto stainless steel and chemically characterized. Their anti-adhesive properties were evaluated in vitro towards Escherichia coli by performing shear-flow induced detachment experiments. Increasing the wall shear stress facilitated E. coli cell detachment, irrespective of the coating characteristics. When nanosilver was incorporated, cell detachment was lower, probably due to the affinity of the embedded silver for biological components of the cell wall. The presence of methyl groups in the matrix network could also promote enhanced hydrophobic interactions. Within the population fraction remaining attached to the coating under increasing shear flow, different association phenotypes were observed, viz. progressively lying flat, moving laterally, remaining tethered, or rotating by a single anchoring point, until alignment with the flow direction. This re-orientation phenotype and its relation with detachment were dependent of the coating. The effects of such heterogeneities should be more deeply explored. [ABSTRACT FROM PUBLISHER]

Abstract: We have studied the deposition of AlCoCrCuFeNi high entropy alloy (HEA) thin films on Si (100) substrates by DC magnetron sputtering process. Three mosaic targets have been used for easily tailoring the film composition. Energy dispersive X-ray spectrometry analysis has shown that chemical composition can be modified around the nominal value by tuning the ratio of the powers applied to the magnetron targets. The deposition rate is directly related to the power sum. Moreover, various surface morphologies have been evidenced by scanning electron microscopy and correlated to the crystalline phases present in the films. Morphology and crystalline structure have been found to depend on the chemical composition. Wetting contact angle has been measured with water droplets, showing that the hydrophobic properties of the thin films depend on their characteristics. [Copyright &y& Elsevier]

Adhesion of bacteria on biomedical implant surfaces is a prerequisite for biofilm formation, which may increase the chances of infection and chronic inflammation. In this study, we employed a novel electrospray-based technique to develop an antibacterial surface by efficiently depositing silica homogeneously onto polyethylene terephthalate (PET) film to achieve hydrophobic and anti-adhesive properties. We evaluated its potential application in inhibiting bacterial adhesion using both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria. These silica-deposited PET surfaces could provide hydrophobic surfaces with a water contact angle greater than 120° as well as increased surface roughness (root mean square roughness value of 82.50 ± 16.22 nm and average roughness value of 65.15 ± 15.26 nm) that could significantly reduce bacterial adhesion by approximately 66.30% and 64.09% for E. coli and S. aureus, respectively, compared with those on plain PET surfaces. Furthermore, we observed that silica-deposited PET surfaces showed no detrimental effects on cell viability in human dermal fibroblasts, as confirmed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide and live/dead assays. Taken together, such approaches that are easy to synthesize, cost effective, and efficient, and could provide innovative strategies for preventing bacterial adhesion on biomedical implant surfaces in the clinical setting. [ABSTRACT FROM AUTHOR]

[Display omitted] • All coatings could enhance quality and durability of rotary blades. • TiAlN and CrN coated blades showed better mechanical properties. • Self-lubricating endow PTFE based coatings with good wear and anti-adhesion. • PTFE coating is more economically method to extend service life of blade. Coating is an effective method to enhance the surface properties of rotary tillage blades. In order to improve the wear resistance and anti-adhesive properties of rotary blades, four different materials TiAlN, CrN, PTFE and Ni-P-PTFE were selected to modified original blades. The mechanical properties, X-ray diffraction (XRD), wear performance, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), soil cutting resistance were tested and analyzed to investigate wear mechanism and evaluate the improvement of tribological and anti-adhesive properties of different coating methods. The 14 days field test was carried on to verify the experimental results. The results showed that metal coatings (TiAlN, CrN) had higher flexural strength and hardness than plastic coatings (PTFE based coatings). All coated blades possess better wear and anti-adhesive properties. PTFE based coating had better wear resistance, and Ni-P-PTFE coating had the lowest the average friction coefficient (0.32) and the lowest weight loss rate (0.4 g/ha) after 14 days operating in the field. And the Ni-P-PTFE coated blade also had the lowest soil cutting resistance. Combined with economic analysis, PTFE coating is more suitable and economically method to improve the wear resistance and anti-adhesive properties of rotary blades, and further extended their service life. [ABSTRACT FROM AUTHOR]

Nine strains of Lactiplantibacillus plantarum and one strain of Lacticaseibacillus paracasei that were recently isolated from prickly pears, fresh figs and blackberries, which are traditionally and largely consumed fruits in Kabylia (north of Algeria), were studied here for their antagonism and antioxidant properties as well as for production of exopolysaccharides. With respect to their inhibitory properties, these strains were tested against three food representative pathogens including Escherichia coli ATCC 8739, Staphylococcus aureus 2S6 and Listeria monocytogenes 162. The antagonism of these pathogens was attributable to lactic acid production, present in the cell free supernatant, at concentrations ranging from 9 to 16.74 g/L. The anti-adhesive properties observed on polystyrene or eukaryotic Caco-2 cells were exerted in a strain dependent-manner. Indeed, the scores obtained ranged from 27% to 75% for S. aureus 2S6, 54% to 95% for L. monocytogenes 162, and 50% to 97% for E. coli ATCC 8739. The co-aggregation of these Lactobacillus strains with the aforementioned target bacteria appeared to be exerted in a strain-dependent manner, with noticeably the upmost rate for Lb. paracasei FB1 on S. aureus 2S6. Interestingly, these novel Lactobacillus strains were able to produce a large amount (315.55 to 483.22 mg/L) of exopolysaccharides, and showed a significant scavenging activity on the 2,2-di-phényl-2-picrylhydrazyle (DPPH) synthetic free radical with rates of 51% to 56%. Of note, the highest antioxidant activity was observed for Lb. paracasei FB1 using the culture supernatants, intact cells or the intracellular extract. The statistical analysis of these data using the principal component analysis (ACP) enabled us to establish three distinct clusters with potential applications as bioprotective and/or probiotic agents, following further evaluation. [ABSTRACT FROM AUTHOR]

Interactions of three Ru(II) chlorophenyl terpyridine complexes: [Ru(Cl-Ph-tpy)(en)Cl]Cl (1), [Ru(Cl-Ph-tpy)(dach)Cl]Cl (2) and [Ru(Cl-Ph-tpy)(bpy)Cl]Cl (3) (Cl-Ph-tpy = 4′-(4-chlorophenyl)-2,2′:6′,2′′-terpyridine, en = 1,2-diaminoethane, dach = 1,2-diaminocyclohexane, bpy = 2,2′-bipyridine) with human serum albumin (HSA), calf thymus DNA and a double-helical oligonucleotide d(CGCGAATTCGCG) 2 (1BNA) were examined. Fluorescence emission studies were used to assess the interactions of complexes with HSA, which were of moderate strength for 1 and 2. Molecular docking allowed us to predict mostly π-π stacking and van der Waals interactions between the complexes and the protein. We suggest that the complexes bind to a novel site on HSA, which is different from its druggable sites I, II or III. We suggest a partial intercalation of complexes through the minor groove as a possible mode of interaction with double-helical DNA. Finally, when applied to normal extravillous cell line HTR8/SVneo and JAr choriocarcinoma cell line, complexes 1 and 2 exerted anti-adhesive properties at very low doses, whereas complex 3 had a negligible effect. The obtained results are completion of our studies of Ru(II) terpyridyl complexes that carry N-N ancillary ligands. We suggest a new research direction towards studying the cellular effects of Ru(II) polypyridyl compounds. Best docked poses of complex-[Ru(Cl-Ph-tpy)(dach)Cl]+ (Cl-Ph-tpy, 4′-(4-chlorophenyl)-2,2′:6′,2′′-terpyridine; dach, 1,2-diaminocyclohexane) on human serum albumin and dodecamer double-stranded oligonucleotide as assessed by molecular docking. Linear dichroism study of intercalation of the complex into a full-length double-helical DNA. The complex inhibits the adhesion of normal cells -HTR-8/SVneo and tumour cells - JAr choriocarcinoma. Unlabelled Image • Ru(II) terpyridine coordination complexes are potential anti-tumour compounds. • Confident assessment of metallodrugs-to-DNA binding mode through linear dichroism. • Different binding of Ru(II) terpyridine complexes to human and bovine serum albumin. • Novel druggable site on human serum albumin for Ru(II) terpyridine complexes. • DNA accommodates Ru(II) terpyridines using an intercalation through minor groove. [ABSTRACT FROM AUTHOR]

Biofilm, naturally formed by microorganisms as integrated surface-bound communities, is one of the reasons for the development of antimicrobial resistance. Haemophilus spp. are common and representative opportunistic Gram-negative rods forming from the upper respiratory tract microbiota. The aim of this paper was to evaluate the influence of thiazolidine-2,4-dionebased azolidine and chlorophenylthiosemicarbazone hybrids against both planktonic and biofilm-forming Haemophilus spp. cells. The in vitro activity against planktonic and biofilm-forming cells of the tested compounds were evaluated by using the broth microdilution method. These activities were detected against reference and clinical strains of Haemophilus spp. on the basis of MICs (minimal inhibitory concentrations) and MBICs (minimal biofilm inhibitory concentrations). In addition, anti-adhesive properties of these compounds were examined. The target compounds showed potential activity against planktonic cells with MIC = 62.5–500 mg/L and biofilm-forming cells with MBIC = 62.5–1000 mg/L. The observed anti-adhesive properties of the tested compounds were reversible during long-term incubation in a lower concentration of compounds. [ABSTRACT FROM AUTHOR]

Human milk is the gold standard for nourishment of early infants because it contains a number of bioactive components, such as human milk oligosaccharides (HMOs). The high concentration and structural diversity of HMOs are unique to humans. HMOs are a group of complex and diverse glycans that are resistant to gastrointestinal digestion and reach the infant colon as the first prebiotics. N-acetyl-glucosamine containing oligosaccharides were first identified 50 years ago as the 'bifidus factor', a selective growth substrate for intestinal bifidobacteria, thus providing a conceptual basis for HMO-specific bifidogenic activity. Bifidobacterial species are the main utilisers of HMOs in the gastrointestinal tract and represent the dominant microbiota of breast-fed infants, and they may play an important role in maintaining the general health of newborn children. Oligosaccharides are also known to directly interact with the surface of pathogenic bacteria, and various oligosaccharides in milk are believed to inhibit the binding of pathogens and toxins to host cell receptors. Furthermore, HMOs are thought to contribute to the development of infant intestine and brain. Oligosaccharides currently added to infant formula are structurally different from the oligosaccharides naturally occurring in human milk and, therefore, they are unlikely to mimic some of the structure-specific effects. In this review, we describe how HMOs can modulate gut microbiota. This article summarises information up to date about the relationship between the intestinal microbiota and HMOs, and other possible indirect effects of HMOs on intestinal environment.