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Nanomaterials (NMs) can be produced in plenty of variants posing several challenges for NM hazard and risk assessment. Metabolomic profiling of NM-treated cells and tissues allows for insights into underlying Mode-of-Action (MoA) and offers several advantages in this context. It supports the description of Adverse Outcome Pathways (AOPs) and, therefore, tailored AOP-based hazard testing strategies. Moreover, it bears great potential for biomarker discovery supporting toxicity prediction. Here, we applied metabolomics profiling to cells treated with four well-selected SiO2 variants, differing in structure, size and surface charge. TiO2 NM-105 served as a benchmark. Responses were studied in vitro in rat lung epithelial cells (RLE-6TN) and alveolar macrophages (NR8383) and compared to in vivo responses in rat lung tissues obtained from in vivo instillation and short-term inhalation studies (STIS). Time- and concentration-dependent changes were observed in both in vitro models but with cell-type specific responses. Overall, the levels of lipids and biogenic amines (BAs) tended to increase in epithelial cells but decreased in macrophages. Many identified metabolites like Met-SO, hydroxy-Pro and spermidine were related to oxidative stress, indicating that oxidative stress contributes to the MoA for the selected NMs. Several biomarker candidates such as Asp, Asn, Ser, Pro, spermidine, putrescine and LysoPCaC16:1 were identified in vitro and verified in vivo. In this study, we successfully applied a metabolomics workflow for in vitro and in vivo samples, which proved to be well suited to identify potential biomarkers, to gain insights into NM structure–activity relationship and into the underlying MoA.

In the field of medical imaging, multimodal nanoparticles combining complementary imaging modalities can give rise to new forms of imaging techniques that are able to make diagnosis more precise and confident. In this context, resolution and sensitivity have often to be gathered into a single imaging probe, by combination of MRI and optical imaging for instance. Gadolinium chelate (Gd-CAs) loaded nanohydrogels, obtained from chitosan (CS) and hyaluronic acid (HA) matrix, have shown their efficiency to greatly improve MRI contrast (r1 ≥ 80 mM−1 s−1). In this study, nanohydrogels were made intrinsically fluorescent by chitosan pre-functionalization and a series of fluorescent chitosans were obtained by covalent grafting of rhodamine (Rhod: 6.3µM) or fluorescein (Fluo: 7.3µM) tags. By combining DOSY and fluorescence data, fluorescent chitosans (CS-Rhod and CS-Fluo) with a low degree of substitution were then selected and used to encapsulate high gadolinium loadings to obtain efficient magneto-optical nanohydrogels.

Bovine hydroxyapatite (BHA) and BHA blended with clinoptilolite (CLIN) and alumina (Al2O3) coatings were synthesized using pulsed laser deposition (PLD) with a KrF* excimer laser source (λ = 248 nm...

The advancement of nanotechnology in the last decade has developed an abundance of novel and intriguing TiO2-based nanomaterials that are widely used in many sectors, including industry (as a food additive and colorant in cosmetics, paints, plastics, and toothpaste) and biomedicine (photoelectrochemical biosensing, implant coatings, drug delivery, and new emerging antimicrobial agents). Therefore, the increased use of engineered nanomaterials in the industry has raised serious concern about human exposure and their unexpected cytotoxic effects. Since inhalation is considered the most relevant way of absorbing nanomaterials, different cell death mechanisms induced in MRC-5 lung fibroblasts, following the exposure to functionalized TiO2 NPs, were investigated. Long-term exposure to TiO2 nanoparticles co-doped with 1% of iron and nitrogen led to the alteration of p53 protein activity and the gene expression controlled by this suppressor (NF-kB and mdm2), DNA damage, cell cycle disruptions at the G2/M and S phases, and lysosomal membrane permeabilization and the subsequent release of cathepsin B, triggering the intrinsic pathway of apoptosis in a Bax- and p53-independent manner. Our results are of major significance, contributing to the understanding of the mechanisms underlying the interaction of these nanoparticles with in vitro biological systems, and also providing useful information for the development of new photocatalytic nanoparticles that are active in the visible spectrum, but with increased biocompatibility.

Several reports on amorphous silica nanomaterial (aSiO2 NM) toxicity have been questioning their safety. Herein, we investigated the in vivo pulmonary toxicity of four variants of aSiO2 NM: SiO2_15_Unmod, SiO2_15_Amino, SiO2_7 and SiO2_40. We focused on alterations in lung DNA and protein integrity, and gene expression following single intratracheal instillation in rats. Additionally, a short-term inhalation study (STIS) was carried out for SiO2_7, using TiO2_NM105 as a benchmark NM. In the instillation study, a significant but slight increase in oxidative DNA damage in rats exposed to the highest instilled dose (0.36 mg/rat) of SiO2_15_Amino was observed in the recovery (R) group. Exposure to SiO2_7 or SiO2_40 markedly increased oxidative DNA lesions in rat lung cells of the exposure (E) group at every tested dose. This damage seems to be repaired, since no changes compared to controls were observed in the R groups. In STIS, a significant increase in DNA strand breaks of the lung cells exposed to 0.5 mg/m3 of SiO2_7 or 50 mg/m3 of TiO2_NM105 was observed in both groups. The detected gene expression changes suggest that oxidative stress and/or inflammation pathways are likely implicated in the induction of (oxidative) DNA damage. Overall, all tested aSiO2 NM were not associated with marked in vivo toxicity following instillation or STIS. The genotoxicity findings for SiO2_7 from instillation and STIS are concordant, however, changes in STIS animals were more permanent/difficult to revert.

This study assessed the distribution of heavy metals in the gills, kidney, and liver, correlated with the severity of histopathological changes, of three fish species with different feeding habitats (Barbus barbus, Squalius cephalus, and Chondrostoma nasus) from the Crișul Negru river, Romania. The levels of copper (Cu), chromium (Cr), cadmium (Cd), lead (Pb), and zinc (Zn) in fish tissues were measured by atomic absorption spectrophotometry. Histopathology and the expressions of TNF-α and proliferation cell nuclear antigen (PCNA) were investigated by immunohistochemistry and Western blot. Our data suggest a significant correlation between the bioconcentration level of metals and structural changes. The carnivorous species was the most affected compared to the omnivorous and herbivorous ones, and the most affected organ was the kidney. Moreover, the correlation of tissue damage with the PCNA and TNF-α expression levels revealed that the herbivorous species presented less extended lesions, likely due to higher activated repair mechanisms and lower levels of inflammation. In conclusion, our data and the subsequent statistical analysis suggest that feeding behavior could be correlated with the histopathological alterations and might be used for a more profound evaluation of aquatic environment safety and analysis of aquatic ecosystems.

In this work, novel polymeric mixed micelles from Pluronic F127 and Cremophor EL were investigated as drug delivery systems for Norfloxacin as model antibiotic drug. The optimal molar ratio of surfactants was determined, in order to decrease critical micellar concentration (CMC) and prepare carriers with minimal surfactant concentrations. The particle size, zeta potential, and encapsulation efficiency were determined for both pure and mixed micelles with selected composition. In vitro release kinetics of Norfloxacin from micelles show that the composition of surfactant mixture generates tunable extended release. The mixed micelles exhibit good biocompatibility against normal fibroblasts MRC-5 cells, while some cytotoxicity was found in all micellar systems at high concentrations. The influence of the surfactant components in the carrier on the antibacterial properties of Norfloxacin was investigated. The drug loaded mixed micellar formulation exhibit good activity against clinical isolated strains, compared with the CLSI recommended standard strains (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29213, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922). P. aeruginosa 5399 clinical strain shows low sensitivity to Norfloxacin in all tested micelle systems. The results suggest that Cremophor EL-Pluronic F127 mixed micelles can be considered as novel controlled release delivery systems for hydrophobic antimicrobial drugs.

Gel microemulsion combines the advantages of the microemulsion, which can encapsulate, protect and deliver large quantities of active ingredients, and the gel, which is so appreciated in the cosmetic industry. This study aimed to develop and characterize new gel microemulsions suitable for topical cosmetic applications, using grape seed oil as the oily phase, which is often employed in pharmaceuticals, especially in cosmetics. The optimized microemulsion was formulated using Tween 80 and Plurol® Diisostearique CG as a surfactant mix and ethanol as a co-solvent. Three different water-soluble polymers were selected in order to increase the viscosity of the microemulsion: Carbopol® 980 NF, chitosan, and sodium hyaluronate salt. All used ingredients are safe, biocompatible and biodegradable. Curcumin was chosen as a model drug. The obtained systems were physico-chemically characterized by means of electrical conductivity, dynamic light scattering, polarized microscopy and rheometric measurements. Evaluation of the cytotoxicity was accomplished by MTT assay. In the final phase of the study, the release behavior of Curcumin from the optimized microemulsion and two gel microemulsions was evaluated. Additionally, mathematical models were applied to establish the kinetic release mechanism. The obtained gel microemulsions could be effective systems for incorporation and controlled release of the hydrophobic active ingredients.

The occurrence of opportunistic local infections and improper integration of metallic implants results in severe health conditions. Protective and tunable coatings represent an attractive and challenging selection for improving the metallic devices’ biofunctional performances to restore or replace bone tissue. Composite materials based on hydroxyapatite (HAp), Kanamycin (KAN), and fibroblast growth factor 2 (FGF2) are herein proposed as multifunctional coatings for hard tissue implants. The superior cytocompatibility of the obtained composite coatings was evidenced by performing proliferation and morphological assays on osteoblast cell cultures. The addition of FGF2 proved beneficial concerning the metabolic activity, adhesion, and spreading of cells. The KAN-embedded coatings exhibited significant inhibitory effects against bacterial biofilm development for at least two days, the results being superior in the case of Gram-positive pathogens. HAp-based coatings embedded with KAN and FGF2 protein are proposed as multifunctional materials with superior osseointegration potential and the ability to reduce device-associated infections.

Background: The immense variety and constant development of nanomaterials (NMs) raise the demand for a facilitated risk assessment, for which knowledge on NMs mode of actions (MoAs) is required. For this purpose, a comprehensive data basis is of paramountcy that can be obtained using omics. Furthermore, the establishment of suitable in vitro test systems is indispensable to follow the 3R concept and to master the high number of NMs. In the present study, we aimed at comparing NM effects in vitro and in vivo using a multi-omics approach. We applied an integrated data evaluation strategy based on proteomics and metabolomics to four silica NMs and one titanium dioxide-based NM. For in vitro investigations, rat alveolar epithelial cells (RLE-6TN) and rat alveolar macrophages (NR8383) were treated with different doses of NMs, and the results were compared to effects on rat lungs after short-term inhalations and instillations at varying doses with and without a recovery period.Results: Since the production of reactive oxygen species (ROS) is described to be a critical biological effect of NMs, and enrichment analyses confirmed oxidative stress as a significant effect upon NM treatment in vitro in the present study, we focused on different levels of oxidative stress. Thus, we found opposite changes for proteins and metabolites that are related to the production of reduced glutathione in alveolar epithelial cells and alveolar macrophages, illustrating that NMs MoAs depend on the used model system. Interestingly, in vivo, pathways related to inflammation were affected to a greater extent than oxidative stress responses. Hence, the assignment of the observed effects to the levels of oxidative stress was different in vitro and in vivo as well. However, the overall classification of “active” and “passive” NMs was consistent in vitro and in vivo.Conclusions: The consistent classification indicates both tested cell lines to be suitable for NM toxicity assessment even though the induced levels of oxidative stress strongly depend on the used model systems. Thus, the here presented results highlight that model systems need to be carefully revised to decipher the extent to which they can replace in vivo testing.

This report is the first research study that aims to explore the molecular mechanisms involved in the in vitro pulmonary cytotoxicity triggered by long-term exposure to silicon-based quantum dots (QDs). Human lung fibroblasts (MRC-5 cell line) were exposed to 5 &micro, g/mL silicon-based QDs for 5 weeks and the concentration was increased up to 40 &micro, g/mL QDs during the next 4 weeks. Cell viability and population doubling level were calculated based on Trypan blue staining. The expression levels of proteins were established by Western blotting and the telomeres&rsquo, length was determined through Southern blotting. Prolonged exposure of lung fibroblasts to QDs reduced the cell viability by 10% compared to untreated cells. The level of p53 and apoptosis-inducing factor (AIF) expression increased during the exposure, the peak intensity being registered after the seventh week. The expressions of autophagy-related proteins, Beclin-1 and LC-3, were higher compared to untreated cells. Regarding the protein expression of Nrf-2, a progressive decrease was noticed, suggesting the downregulation of a cytoprotective response to oxidative stress. In contrast, the heat shock proteins&rsquo, (HSPs) expression was increased or maintained near the control level during QDs exposure in order to promote cell survival. Furthermore, the telomeres&rsquo, length was not reduced during this exposure, indicating that QDs did not induce cellular senescence. In conclusion, our study shows that silicon-based QDs triggered the activation of apoptotic and autophagy pathways and downregulation of survival signaling molecules as an adaptive response to cellular stress which was not associated with telomeres shortening.

Methotrexate (MTX) chemotherapy is often limited by its severe side effects, which include nephrotoxicity. In the continuous search for efficient antioxidants that could ameliorate this toxic condition of MTX, our study aimed to evaluate the efficiency of N-acetyl cysteine (NAC), Trolox methyl ether (Trolox-Me), and curcumin as potent antioxidants using an in vitro model of MTX-induced toxicity. Human embryonic kidney (HEK293) cells were pre-exposed to different antioxidants for 2 h prior to MTX (5 μM and 50 μM). After 24 h of exposure to MTX, the cell viability and morphology were assessed, activities of antioxidant enzymes and levels of lipid peroxidation were measured by spectrophotometrically methods, and protein expression was determined by Western blotting. Exposure to MTX at concentrations between 1 and 100 μM for 24 h decreased cell viability in a dose-dependent manner and was correlated with the increase in p53 protein expression. All three antioxidants tested have proved that they can inhibit the apoptosis induced by MTX, as revealed by the expression of heat shock proteins (Hsp27, Hsp60, Hsp70 and Hsp90). Pre-treatment of cells with 50 μM of Trolox-Me succeeded to significantly decrease the MTX-induced cell death. The reduction in the activities of glutathione reductase and glutathione S-transferase after MTX incubation was correlated with a low level of GSH, and was attenuated by the pre-incubation with Trolox-Me or curcumin; these antioxidants being able to maintain enough GSH for the reactions of conjugation with MTX metabolites in order to decrease its toxicity. In conclusion, the pre-treatment with curcumin, Trolox-Me or NAC proved extremely effective at blocking MTX toxicity at the concentration investigated in vitro on kidney cells. The results of our study encourage further clinical assessments in order to use these antioxidants in dietary prevention of renal side effects of MTX.

Benzenthonium chloride (BEC, Hyamine 1622) is a quaternary ammonium surfactant with cationic properties widely used in cleaning, sanitation, and medical products that can become harmful to humans and also to the environment. This study aimed to evaluate its acute effects on Cyprinus carpio fish in terms of oxidative stress and morphological changes on hepatic tissue in order to show the sub-lethal toxicity of BEC. Fish were exposed to 1 mg/L BEC for 24, 48, and 96 h, and the liver samples were collected. The most significant changes were noticed after 96 h of exposure when the entire antioxidant enzyme system was affected. The activities of catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase decreased by 44%, 31%, 30%, and 45%, respectively, compared to control. Glucose-6-phosphate dehydrogenase activity decreased by 29% after 96 h of control, inducing a reduction of NADPH formation which decreased by half the level of reduced glutathione, the main non-enzymatic antioxidant. These effects correlated with the raised value of lipid peroxidation after 96 h and the morphology changes on hepatic tissue, such as cytoplasmic vacuolization and nuclear hypertrophy that could affect the normal function of the liver. All of these results showed acute toxicity of BEC on C. carpio after 96 h of exposure, causing oxidative stress response at the hepatic level.

Due to their intrinsic viscosity and hydrophilicity, nanohydrogel systems are used to significantly increase the efficiency of commercial contrast agents for MRI and thus effectively improve the sensitivity of the MRI technique. Since chitosan (CS) is a biocompatible polysaccharide frequently used in biomedical applications, we aimed to prepare chitosan nanohydrogels (NGs) by ionic gelation, the polysaccharide being further grafted with rhodamine (RBITC) and fluorescein isothiocyanate (FITC). In this way, the cytotoxic effect of different concentrations (5, 15, 30, 60, and 120 µg/mL) of the fluorescent CS-FITC and CS-RBITC NGs was investigated by assessing the plasma membrane integrity and the metabolic activity of RAW 264.7 murine macrophages and A20 mouse lymphoma B cells following exposure for 6 and 24 h. The cell viability (MTT assay) and lactate dehydrogenase activity were analyzed by spectrophotometric methods, while cellular uptake was observed by fluorescence microscopy. Our results showed that the exposure to CS-FITC and CS-RBITC NGs for 6 and 24 h did not induce significant changes to RAW 264.7 and A20 cells compared to control, proving a good nanogel biocompatibility for both cell lines. In addition, the fluorescence microscopy showed that cellular uptake was quite rapid and efficient for the NGs tested. Taking all of these into consideration, we can conclude that all types of nanohydrogels were biocompatible, being internalized in both cell types with predominantly cytoplasmic localization.

Graphene quantum dots (GQDs) represent nanoscale structures with strong quantum and exceptional photoluminescence properties. These particles have promising applications in nanomedicine, specifically for diagnostics, cargo delivery, photothermal therapy and bioimaging. In this context, we aimed to characterize GQDs available on the market for further utilization for in vivo purposes. Transmission and scanning electron microscopy (TEM and SEM), and energy dispersive X-ray spectroscopy (EDX), were used to characterize the morphology and elemental composition of GQDs. In addition, the hydrodynamic size and the zeta potential were measured for these nanoparticles. Their biocompatibility was investigated on human fibroblast lung cells (MRC-5 cell line) after 24 and 72 h of incubation with concentrations up to 200 μg/mL of GQDs. TEM images showed graphene sheets with few wrinkle structures, the dots having uniform diameters in the range between 1.0 and 5.0 nm. SEM examination revealed the three-dimensional structure with a sponge-like aspect and pores of various sizes. Their tendency to aggregate provided the formation of aggregates with sizes of hundreds of nanometers, as revealed by the hydrodynamic diameter of about 270 nm. A negative zeta potential of −16 mV confirmed the anionic character of GQDs. Concentrations up to 50 μg/mL exhibited a low toxicity in lung cells, as revealed by MTT assay and fluorescent microscopy of actin cytoskeleton after both time intervals, confirming potential further testing on animals for clinical purposes. However, the high doses of GQDs induced cell death and must be avoided in future. Given the new experimental evidence obtained on GQDs, more knowledge has been achieved, which is very useful for prospective research to revolutionize the future of nanomedicine and biotechnology.

Nanogels are a novel class of three-dimensional cross-linked polymers able to retain high amounts of water in their network structure, with large potential applications in nanomedicine. In our study, the polymer matrix selected was chitosan, as this polysaccharide biopolymer composed of N-acetylglucosamine and glucosamine residues exhibits great biocompatibility and low toxicity. The preparation was performed by ionic gelation in the presence of hyaluronic acid and sodium tripolyphosphate, with rhodamine or fluorescein isothiocyanate molecules grafted on a chitosan backbone. In order to validate the possible usage of these chitosan-fluorophores conjugates for fluorescence imaging purposes in cancer diagnostics and therapy, their biological effect was assessed on SVEC4-10 cells (a simian virus 40-transformed mouse microvascular endothelial cell line). Cell viability, membrane integrity and nanogels uptake were examined following exposure for 6 and 24 h at concentrations up to 120 µg/mL. A good biocompatibility was obtained after both time intervals of incubation with nanogels, with no increase in cell death or membrane damage being noticed as compared to control. By examination on confocal laser scanning microscopy, both types of fluorescent nanogels agglomerated on the surface of the cell membrane, their cellular internalization being observed only for few cells, preferentially at the cell periphery. In conclusion, based on the biocompatibility of the nanogels, these can further incorporate gadolinium for an improved magnetic resonance imaging effect in nanomedicine.

It is already well known that the tissue-implant interface is one of the most critical factors for the success of the implant integration. The use of bioactive and biomimetic surfaces is of great interest in biomedical applications especially in tissue engineering. Therefore, in our study we aimed to obtain successful coatings based on hydroxyapatite, antibiotics and growth factors in order to increase the biocompatibility of commercial implant materials by promoting cell attachment and growth without toxic effects as well as inhibition of microbial biofilm formation. In this way, homogenous mixtures of hydroxyapatite, kanamycin and fibroblast growth factor (HAP/KAN, HAP/FGF and HAP/KAN/FGF) were coated on titanium-based metal plates for hip replacement implants. The coatings were able to impair the initial adherence of bacterial cells and to reduce the biofilm formation throughout the release of antibiotic. The cytocompatibility of these samples was investigated on murine normal osteoblasts (MC3T3-E1 cell line) with fibroblast-like morphology by evaluating their influence on cellular viability and potential to generate an inflammatory response. In addition, the adhesion and proliferation, as well as the actin cytoskeleton organization, were observed after 24 h of cell culture on these coatings. The results confirmed the biocompatibility of all coatings, the cell number counted for HAP/KAN/FGF sample being equal to control. Since it is well known that NO is a marker of inflammation with an essential role in regulating apoptotic death and cell viability, our study showed that cell growth on these surfaces did not induce nitric oxide (NO) release, NO level being maintained close to control values for all tested samples. Also, an excellent cell adherence and spreading on these coatings deposited on hip implants was evidenced by fluorescence microscopy, supporting their usage as substrates in tissue engineering applications. Acknowledgements. This work has been funded by the Operational Programme Human Capital of the Ministry of European Funds through the Financial Agreement 51668/09.07.2019, SMIS code 124705, and through the project no. 77PD/2018 NANO-BIO-INT (PN-III-P1-1.1-PD-2016-1562).

Our study reports the fabrication and characterization (surface morphology, hydrophobicity/hydrophilicity, photocatalytic efficiency) of cotton fibers treated by various methods with graphene oxide decorated with Fe, N-doped TiO2 nanoparticles. Designed as prospective industrial self-cleaning, antimicrobial and biocompatible textiles, microbiological and cytotoxicity tests were performed on these particles-treated fibers to validate their qualities. The photocatalytic effect was dependent on chemicals used to disperse the nanoparticles, the parameters of the treatment, the fiber structure and composition of the material. The double and triple treatment of the textiles with the same particle dispersion resulted in a relatively uniform coverage of cotton fibers with relatively large amounts of particles. A larger amount of doped TiO2 particles demonstrated a better photocatalytic effect under visible light. The material's hydrophobicity increased with the number of treatments due to the deposition of successive layers of reduced graphene, ensuring self-cleaning properties. The photocatalyst-treated cotton fabrics exhibited an increased resistance to Enterococcus faecalis and Escherichia coli colonization, and also high biocompatibility, as they did not affect the cell viability, membrane integrity and morphology, nor induce inflammation. All these data confirm the improved properties of cotton fibers treated with graphene oxide decorated with Fe, N-doped TiO2 particles in order to be used as industrial self-cleaning and biocompatible textiles.

Two ZnO materials of spherical hierarchical morphologies, with hollow (ZnOHS) and solid cores (ZnOSS), were obtained through the hydrolysis of zinc acetylacetonate in 1,4-butanediol. The nature of the defects and surface reactivity for the two ZnO materials were investigated through photoluminescence, X-ray photoelectron spectroscopy, and electron paramagnetic resonance (EPR) spectroscopy proving the coexistence of shallow and deep defects and, also, the presence of polyol byproducts adsorbed on the outer layers of the ZnO samples. The EPR spectroscopy coupled with the spin-trapping technique showed that the surface of the ZnO samples generates reactive oxygen species (ROS) like hydroxyl (•OH) and singlet oxygen (1O2) as well as carbon-centered radicals. The ZnO materials exhibited a wide spectrum of antimicrobial activity, being active against Gram-positive, Gram-negative, and fungi strains, both in planktonic and, more importantly, adherent growth states. The decrease of antimicrobial efficiency in the ...

Textile materials can be easily used as a support for the nano-decoration with active particles in order to gain new features such as self-cleaning, antimicrobial efficiency, water repellency, mechanical strength, color change and protection against ultraviolet radiations. In this context, our present research reports the fabrication and characterization (physico-chemical analysis and surface morphology) of cotton fabrics treated with reduced graphene oxide decorated with two types of TiO2 nanoparticles co-doped with 1% iron and nitrogen atoms (TiO2/rGO NPs) and synthesized in different hydrothermal conditions by a simultaneous precipitation of Ti3+ and Fe3+ ions to achieve their uniform distribution or after a sequential precipitation of these two cations for obtaining a higher concentration of iron on the surface of Ti4+ oxyhydroxide. Further, the antimicrobial efficiency of these TiO2/rGO-treated textiles and their influence on human cells were assessed. We demonstrated the successful development of TiO2/rGO coating of cotton fabrics which are harmless for human skin cells and inhibit the growth of Staphylococcus aureus and Enterococcus faecalis. These findings confirm their great potential as novel graphene-based materials for biomedical and photocatalytic applications and this approach could be used for the large-scale fabrication of innovative self-cleaning and antimicrobial textiles.

Gills are major targets for acute metal toxicity in fish, due to their permanent contact with aquatic pollutants. To assess the effects of metals on gills of the Leuciscus cephalus (chub), fish individuals were collected from two sites in the Tur River, Romania, in upstream (site 1) and downstream (site 2) of a metal pollution source. Quantitative and hyperspectral analyses showed that Zn, Sr, and Fe concentrations were significantly higher in gills from site 2 compared with site 1. Malondialdehyde and advanced oxidation protein products levels increased 17 and 28%, respectively, whereas reduced glutathione level diminished significantly in the gills of fish collected from site 2 compared to site 1. The activities of superoxide dismutase, catalase, and glutathione-S-transferase increased significantly at 41, 21, and 28%, respectively. Proliferating cell nuclear antigen (PCNA) protein levels, as well as the amount of DNA damage, were significantly increased for site 2 compared with site 1. The induced oxidative stress generated hyperplasia, hypertrophy, and inflammation in the epithelial cells and apoptosis. Hence, this could suggest that gill cells have tried to counteract the oxidative stress-induced DNA fragmentation by PCNA up-regulation, but the PCNA expression decreased on longer time due to the low level of GSH, resulting in apoptosis.

The aim of the present paper is to characterize bioinspired chitosan (CS) + hydroxyapatite (HA) coatings with various components ratio on a zirconium alloy with titanium. The coatings were characterized by FT-IR, SEM, hydrophilic/hydrophobic balance, adherence, roughness, electrochemical stability and in vitro cell response. Electrochemical tests, including potentiodynamic polarization curves and electrochemical impedance spectroscopy, were performed in normal saline physiological solution. Cell viability of MC3T3-E1 osteoblasts, lactate dehydrogenase, nitric oxide, and Reactive Oxygen Species (ROS) levels, as well as actin cytoskeleton morphology, were evaluated as biological in vitro tests. The results on in vitro cell response indicated good cell membrane integrity and viability for all samples, but an increased cell number, a decreased ROS level and a better cytoskeleton organization were noticed for the sample with a higher CS content. The coating with highest CS concentration indicated the best performance based on the experimental data. The highest hydrophilic character, highest resistance to corrosion and best biocompatibility as well recommend this coating for bioapplications in tissue engineering.

Two different types of nanoparticles (silicon dioxide and titanium dioxide) were selected within this study in order to analyze the interaction with bovine and human serum albumin. These particles were characterized by transmission and scanning electron microscopy (TEM and SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDXS). In addition, the hydrodynamic size and the zeta potential were measured for all these nanoparticles. The serum proteins were incubated with the nanoparticles for up to one hour, and the albumin adsorption on the particle surface was investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The effect induced on the secondary structure of proteins was analyzed by Fourier transform infrared spectroscopy (FTIR). The results showed that albumin adsorbed on the surface of both types of nanoparticles, but in different quantities. In addition, we noticed different changes in the structure of albumin depending on the physicochemical properties of each type of particle tested. In conclusion, our study provides a comparative analysis between the different characteristics of nanoparticles and the protein corona formed on the particle surface and effects induced on protein structure in order to direct the development of &ldquo, safe-by-design&rdquo, nanoparticles, as their demands for research and applications continue to increase.

In order to obtain textile materials with potential utility in the development of cosmetic textiles, this study examined the deposition by padding of rose and sage microcapsules on woven textile structures, with different fiber compositions (100% cotton and 50% cotton/50% polyester). Cationization of the textile materials was performed to enhance the degree of uptake the pf the microcapsules on the fabrics&rsquo, surface. A commercially acrylate-based binder was used to fix the microcapsules to the textile substrate and to improve the durability against external factors. The finished textile materials were characterized in terms of their physical-mechanical characteristics. The distribution of microcapsules on the fabrics surface before and after five washing cycles and 1000 abrasion cycles was investigated by scanning electron microscopy. The biocompatibility in terms of cell viability, cell membrane integrity and inflammation status of the functionalized fabrics was evaluated on CCD-1070Sk normal human dermal fibroblasts. The cell morphology was evaluated by F-actin staining using fluorescence microscopy and no significant changes were noticed after the incubation in the presence of fabrics compared with control. The in vitro biocompatibility evaluation on human skin cells confirmed the absence of cytotoxicity after the short-term exposure, supporting further in vivo use of these innovative textiles with improved properties.

Tumor hypoxia provides a dynamic environment for the cancer cells to thrive and metastasize. Evaluation of cell growth, cell-cell, and cell surface interactions in hypoxic conditions is therefore highly needed in the establishment of treatment options. Electric cell-substrate impedance sensing (ECIS) has been traditionally used in the evaluation of cellular platforms as a real-time, label-free impedance-based method to study the activities of cells grown in tissue cultures, but its application for hypoxic environments is seldom reported. We present real-time evaluation of hypoxia-induced bioeffects with a focus on hypoxic pH regulation of tumor environment. To this end, multiparametric real-time bioanalytical platform using electrical impedance spectroscopy (EIS) and human colon cancer HT-29 cells is advanced. A time series of EIS data enables monitoring with high temporal resolution the alterations occurring within the cell layer, especially at the cell-substrate level. We reveal the dynamic changes of cellular processes during hypoxic conditions and in response to application of acetazolamide (AZA), a carbonic anhydrase inhibitor. Optical evaluation and pH assessment complemented the electrical analysis towards establishing a pattern of cellular changes. The proposed bioanalytical platform indicates wide applicability towards evaluation of bioeffects of hypoxia at cellular level.