Publications by authors named "Nataliya Kavok"

GdVO:Eu nanoparticles (OVNPs) have previously been shown to exhibit anti-aging effects in old rats.The accelerated aging model (overnutrition in early postnatal ontogenesis (POF)) was used to confirm the effect of OVNPs as a potential geroprotector. A comparative study of the effect of OVNPs, calorierestriction (CR) and CR-mimetic-metformin was carried out using a number of criteria: survival, prooxidant-antioxidant balance in the liver and blood, physiological parameters of male Wistar rats with accelerated aging.

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The control over bacterial diseases requires the development of novel antibacterial agents. The use of antibacterial nanomedicines is one of the strategies to tackle antibiotic resistance. The study was designed to assess the antimicrobial activity of cerium oxide (CeO ) nanoparticles (NP) of two different sizes (CeO NP1 [1-2 nm] and CeO NP2 [10-12 nm]) and their cytotoxicity towards eukaryotic cells.

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Due to its unique redox chemistry, nanoceria is considered as potent free radical scavenger and antioxidant. However, their protective capacity in aging organisms remains controversial. To detect the anti-aging effects associated with the redox activity of 2 and 10 nm nano-CeO2, different test systems were used, including in vitro analysis, in situ assay of mitochondria function and in vivo studies of suitable nano-CeO on aging of male Wistar rats from 22 months-old to the end of life.

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The search for novel antimicrobial agents is of huge importance. Nanomaterials can come to the rescue in this case. The aim of this study was to assess the cytotoxicity and antimicrobial effects of rare-earth-based orthovanadate nanoparticles.

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Nanotechnology can be applied to design antibacterial agents to combat antibiotic resistance. The aim of the present study was to assess the antimicrobial effects and cytotoxicity of GdYVO:Eu nanoparticles (NPs). Biofilm inhibition activity, antimicrobial activity, bacterial viability inhibition and DNA cleavage activity of GdYVO:Eu NPs were studied.

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Nanoparticles (NPs) have been reported to be promising enhancement agents for radiation therapy. The aim of the study was to assess the cytotoxicity of UV non-treated and UV pretreated GdYVO:Eu nanoparticles against erythrocytes and leukocytes by detecting eryptosis and reactive oxygen species (ROS) generation. Levels of intracellular ROS in erythrocytes and leukocytes using a ROS-sensitive dye 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA), as well as eryptosis rate utilizing annexin V staining, following direct exposure to UV-activated and nonactivated NPs were detected by flow cytometry.

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Effect of prolong use of orthovanadate nanoparticles (GdVO/Eu NPs (8 × 25 nm)) on life quality and survival of male Wistar rats on the late stage of ontogenesis (from 23 months to the end of life) has been investigated. Multi-parametric assessment of orthovanadate NPs influences against metformin (Met) which is a well-known calorie restriction mimetic (CR-mimetic) has been completed. The quality of life was assessed by taking into account age-related hallmarks-phenotype and some physiological parameters (condition of the coat, body weight, concentration of thyroxine, rectal temperature) as well as indicators of the pro-oxidant/antioxidant balance of blood and liver (the content of lipid hydroperoxides; aconitase, glutathione peroxidase, glutathione reductase, glutaredoxin activity, and activity of NADP-dehydrogenases (DG) (glucose-6-phosphate DG, malate DG, and isocitrate DG)) in aging animals.

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Both cerium oxide (CeOx) nanoparticles and mefenamic acid (MFA) are known anti-inflammatory agents with hepatoprotective properties and are therefore prescribed for one of the major diseases in the world, nonalcoholic fatty liver disease (NAFLD). To study the potential cytotoxicity and anti-inflammatory effects as well as drug retention of a potential therapeutic CeOx/MFA supramolecular complex, a well-standardized hepatic (HepG2) spheroid model was used. Results showed that the highest cytotoxicity for the CeOx/MFA supramolecular complex was found at 50 μg/mL, while effective doses of 0.

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Biomedical application of rare-earth-based nanoparticles attracts much attention due to their unique optical and redox properties and quite low toxicity. Earlier, we found age-related beneficial effects of rare-earth-based orthovanadate nanoparticles (OV NPs) on the prooxidant/antioxidant balance in liver and blood of Wistar rats, as reported by Nikitchenko et al. (Biol Trace Elem Res (2020).

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Vanadium is an important ultra-trace element nowadays attracting attention with particular emphasis on medical application. But the therapeutic application of vanadium-based drugs is still questionable and restricted due to some toxic side effects. It was found that unique redox properties of vanadium in nanoform provided antioxidant activity and prevented oxidative disturbance in cells in vitro.

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Aim: To evaluate the effects of orally administered gadolinium orthovanadate GdVO4:Eu3+ nanoparticles (VNPs) on the course of chronic carrageenan-induced intestinal inflammation.

Methods: Samples of small intestinal tissue were collected from four groups of rats (intact, after administration of VNPs, with carrageenaninduced intestinal inflammation, with carrageenan-induced intestinal inflammation orally exposed to VNPs) to assess the intestinal morphology and HSP90α expression. Levels of seromucoid, C-reactive protein, TNF-α, IL-1β and IL-10 were determined in blood serum.

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Aim: To assess the phospholipid bilayer of white blood cells (WBCs) and the ability of leukocytes to generate reactive oxygen species (ROS) in rats orally exposed to GdVO:Eu nanoparticle (VNP) solution for 2 weeks by fluorescent probes-ortho-hydroxy derivatives of 2,5-diaryl‑1,3‑oxazole.

Methods: Steady-state fluorescence spectroscopy, i.e.

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It this letter, we report the study of free radicals and reactive oxygen species (ROS) generation in water solutions containing gadolinium orthovanadate GdVO:Eu nanoparticles (VNPs) and their complexes with methylene blue (MB) photosensitizer. The catalytic activity was studied under UV-Vis and X-ray irradiation by three methods (conjugated dienes test, OH· radical, and singlet oxygen detection). It has been shown that the VNPs-MB complexes reveal high efficiency of ROS generation under UV-Vis irradiation associated with both high efficiency of OH· radicals generation by VNPs and singlet oxygen generation by MB due to nonradiative excitation energy transfer from VNPs to MB molecules.

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One of the tasks of current oncology is identification of cancer stem cells and search of therapeutic means capable of their specific inhibition. The paper presents the data on phenotype characteristics of Ehrlich carcinoma cells as convenient and easy-to-follow model of tumor growth. The evidence of cancer stem cells as a part of Ehrlich carcinoma and significance of CD44 and CD44 subpopulations in maintaining the growth of this type of tumor were demonstrated.

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Rare-earth-based nanoparticles (NPs) are widely used as fluorescent probes for imaging in vitro and in vivo. One of the challenges that restrain NPs applications in biomedical research is their effect on subcellular structures. In this paper, the ability of lanthanide NPs to affect the cellular oxidative balance and alter the mitochondrial function was analyzed.

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We report the Förster resonance energy transfer (FRET)-labeling of liposomal vesicles as an effective approach to study in dynamics the interaction of liposomes with living cells of different types (rat hepatocytes, rat bone marrow, mouse fibroblast-like cells and human breast cancer cells) and cell organelles (hepatocyte nuclei). The in vitro experiments were performed using fluorescent microspectroscopic technique. Two fluorescent dyes (DiO as the energy donor and DiI as an acceptor) were preloaded in lipid bilayers of phosphatidylcholine liposomes that ensures the necessary distance between the dyes for effective FRET.

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In this paper the process of nonfunctionalized negatively charged orthovanadate nanoparticle accumulation and redistribution in cells dependent on their shape and size was investigated. Aqueous colloidal solutions of nReVO4:Eu(3+) (Re=Gd, Y, La) luminescent nanocrystals of different sizes and shapes have been synthesized. The average sizes of spherical particles were 2, 20, and 300 nm, of spindle-like particles - 22×6.

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Early experiments have shown that sustained elevation of diacylglycerol (DAG) level in liver cell plasma membranes of aged rats is an essential prerequisite for disturbances in agonist responsiveness of hepatocytes. However, the mechanisms responsible for the age-related rise in DAG content in liver cells have not been clearly identified. The aim of the present study was to determine if phospholipid degradation by endogenous phospholipases precedes the DAG accumulation in liver cells and cell nuclei.

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Background: Thyroid hormones are well known modulators of signal transduction. The effect of hyper- and hypo-thyroidism on diacylglycerol/protein kinase C (DAG/PKC) signaling in cardiomiocytes has been determined. Triiodothyronine (T3) has been shown to prevent the alpha1-adrenoreceptor-mediated activation of PKC but does not alter the stimulation of enzyme and hepatic metabolism by phorbol ethers.

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