Cytotoxic and genotoxic effects of cadmium sulfide nanoparticles.

Cadmium compounds are highly toxic substances characterized by mutagenic, genotoxic and carcinogenic effects, and having high cumulative properties. Application of cadmium nanoparticles (NPs) in medicine stimulates the study of their mechanism of action at the cellular level and at the level of organs and systems, determination of biomarkers of their action, particularly in comparison with the ionic form. The aim of the study was to compare the features of cytotoxic and genotoxic effects of cadmium sulfide (CdS) NPs of different sizes on cell cultures of different histogenesis with those of cadmium chloride (CdCl2). MATERIALS AND METHODS: In this work, we used cadmium compounds in the nanoform: NPs CdS of 4-6 nm and of 9-11 nm in size; and in the ionic form: CdCl2. The studies were conducted in vitro in cell lines - IMR-32, НEК-293 and MАEC. To count viable cells we compared the results of three basic tests: MTT (methyl tetrasolium test), SRB (sulforhodamine B test) and NRU (neutral red uptake test). We evaluated the genotoxic effect of the substances studied in vitro using DNA comet assay in alkaline conditions. RESULTS: CdS NPs and CdCl2 demonstrated pronounced dose-dependent cytotoxic effect in MАEC, НEК-293 and IMR-32 cell lines, by impairing membrane permeability, functioning of mitochondria and lysosomes, and inhibiting the function of protein synthesis. Cytotoxic effect of CdCl2 was the most pronounced, this effect of CdS NPs of 9-11 nm in size being the least pronounced. The comet DNA assay in alkaline conditions revealed a statistically significant increase in DNA comet index when exposed to CdCl2 and CdS NPs in comparison with the negative control, which indicates their genotoxic effect. CdS NPs of 4-6 nm in size showed a more pronounced effect in comparison with those of 9-11 nm in size. CONCLUSION: Elucidation of mechanisms underlying the implementation of toxic effects of cadmium NPs will help in assessing the potential risks associated with their use in industry and developing effective preventive measures. For instance, when planning in vivo studies for toxicological evaluation of nanomaterials and nano-substances containing NPs of cadmium, it is necessary to investigate the mutagenic and carcinogenic risks and to take into account the high likelihood of neurotoxic and cardiovasotoxic effects, along with nephrotoxic effects, since high cytotoxic activity of the investigated compounds of cadmium was detected on the cells of the MАEC line (endothelial origin) and IMR-32 (neuronal origin).

THE EFFECT OF COMBINED ACTION OF ANTIBACTERIAL DRUGS WITH LOW-INTENSIVE LASER RADIATION ON CLINICAL STRAINS S. AUREUS AND S. SALIVARIUS IN THE ORAL CAVITY.

The oral mucosa is constantly contaminated by a large number of microorganisms that may cause diseases such as periodontitis and caries. The present paper aims to study the effectiveness of the antimicrobial effect of combined use of antibacterial drugs (AD) and low-intensity laser radiation (LLR) on S. aureus S. salivarius isolated from the oral cavity. The study included 20 individuals with dental caries, 20 individuals with periodontitis and 10 without any signs of dental disease. The material for the microbacterial study was collected from surfaces of the teeth, oral cavity with dental caries and periodontal pockets. The intensity of bacterial isolation was estimated by two factors: the frequency of isolation and percentage of other aerobic microorganisms. The obtained data demonstrated that the use of several antibacterial drugs had a different impact on the strains of S. salivarius and S. aureus, depending on the source of their collection. The collected isolates were used to determine the effect of a 5 minute laser radiation combined with antibacterial drugs. The simultaneous use of antibacterial therapy and laser radiation showed an increase in the therapeutic effect of all investigated antibiotics followed by the inhibition of the growth presentations in S. aureus and S. salivarius. The application of photodynamic therapy, e.g. LLR, combined with antibacterial drugs allowed to achieve a complete inhibition of the microbial growth.

DYNAMICS OF MORPHOLOGICAL CHANGES OF RATS' ADENOHYPOPHYSIS IN BURN DISEASE.

The article presents data relating to structural changes in rat adenohypophysis in experimental burn disease and its treatment. Experimental studies were conducted for defining peculiarities of structural changes in rats' adenohypophisis without and after skin burn injuries (in 7-14 and 21-30 days) alongside its correction with 0.9% NaCl solution. Application of DNA-cytometry allowed defining subtle mechanisms of pathogenic influence of burn injuries on the organism in general and the cells in particular.

[INFLUENCE OF NANODIAMONDS AND CARBON NANOWIRES ON SURVIVAL AND CELLS STRUCTURE IN CHICKEN EMBRYO].

Aim - to determine the effect of nanodiamonds and carbon nanowires on the survival and ultrastructure of chicken embryo cells. The experiment was carried out on chicken embryos, incubated from eggs of Hy-Line breed. Control and two experimental groups were formed (total number of embryos - 100). Diamond nanoparticles and carbon nanowires were administered on day 3 of incubation as a suspension of a biocompatible dextran. Ultrastructural analysis and general study of embryos state were carried out. The most expressed pathological effects were observed in the group with the introduction of the CNW, which caused visual impairment of embryogenesis that started from the early incubation periods. As for ND we can claim their prolonged impact on the development of embryos, manifested in the gradual deterioration of the embryos condition with the manifestations of the pathology in the provisory organs and the body of embryos. The results of our study demonstrate that both types of nanostructures can cause sublethal and irreversible morphologic changes. Detection of morphological evidence of the impact of nanomaterials at significant distances from the site of administration of nanoparticles shows highly penetrating ability of nanomaterials. The presence of damages specific for each type of nanoparticles shows affinity to various tissues and cellular structures. It is demonstrated that similar, at first glance, impact of nanomaterials, such as the induction of oxidative stress might be caused by specific structural transformations. So, ND cause vacuolization of mitochondria, and the CNW - deformation of their shape and appearance of dark inclusions in them.

[A STUDY OF IMPACT OF MERCURY CHLORIDE ON MYOCARDIUM IN EXPERIMENT].

The article is devoted to the study of the myocardium structural reorganization features under the action of 0,01 LD50 of mercury chloride (II) rats when comparing chronic (30 injections) and subchronic (10 injections) exposures. Structural-metabolic reorganization of the myocardium was studied using histological, histochemical and electron microscopic methods. Computer morphometric analysis with subsequent statistical processing was applied. It was established that the main mechanisms of cardiotoxic effect of mercuric chloride are: hypoxia (due to damage to micro vessels; disorder of myogenic regulation at the expense of damage intercalated discs) and the appearance of cell detrits and abnormal proteins as a result of the destruction of cardiomyocytes. Sensitive to the toxic effects of chloride mercuric in low doses are myofibrils, sarcoplasmic network and the energy apparatus of cardiomyocytes - the mitochondria. It was found that chronic exposure to low doses of mercuric chloride causes non-specific qualitative and quantitative changes in all structural components of the heart, damage to the tissue barrier is ongoing and dynamic and resorptive insufficiency hemomicrocirculatory bed of the heart that leads to chronic swelling that causes the development of diffuse fibrosis and enhances cardiac decompensation activities.

[REACTIVE CHANGES IN SPINAL CORD MOTONEURONS AFTER SCIATIC NERVE INJURY AFTER HIGH-FREQUENCY ELECTROSURGICAL INSTRUMENT APPLICATION].

A new experimental model for tissues connection at peripheral nerve injury site in form of tissues welding was designed. In current study we investigated motoneuron state 1, 3, 6 and 12 weeks after peripheral nerve injury and surgical repair with high-frequency electrosurgical technology. Spinal cord sections was stained by Nissl method and observed with light microscopy. We found that postoperative period in animals from experimental groups characterized by qualitative changes in neurons from spinal motor centers that can be interpreted as compensatory processes as response to alteration. In animals from group with high-frequency electrosurgical technology usage stabilization processes passes more quickly comparatively to animals with epineural sutures. High-frequency electrosurgical technology usage provides less harmful effects on motoneurons than epineural suturing.

CHARACTERISTICS OF RAT LIVER EXPOSED TO NANOPARTICLES OF LEAD COMPOUNDS.

In recent times, the lead becomes great importance in environmental pollution, including its nanoparticles. In the literature, there is little data on the changes in the liver after the exposure with lead nanoparticles. The purpose of this study was the identification and determination of macroscopic, microscopic, and biochemical changes of the structural elements of the rat's liver exposed to the action of lead compounds. The study was carried out on 60 male Wistar rats. The first and second groups of animals were intraperitoneally injected with colloidal solution of nanoparticles of Lead Sulfide size of 10 nm and 30 nm, and the third group was intraperitoneally injected with a solution of nitrate lead. Macroscopic, histological, histochemical, biochemical methods and gas chromatography were used to identify the changes of fatty acids metabolism. The experiment has found that body weights of animals in all tested groups were decreased after 6 weeks of lead nanoparticles injection, while relative liver weight was increased. Levels of total lipids and cholesterol, total protein and albumin in the blood serum in study groups have decreased, and the level of triglycerides and glucose have increased. Moderate dystrophic changes were observed in the histological examinations of the liver, and this was confirmed by morphometric and densitometric parameters. Changes of fatty acid composition of lipids of the liver exposed to nanoparticles were the result of increasing arachidonic fatty acid content and reduction of the stearic fatty acid content. Thus, it has been proven by the experiment that the effect of lead nanoparticles depends on their size.

[Biochemical parameters of blood and morpho-functional state of the liver of experimental animals by the actions of lead sulfide nanoparticles in different time study].

Biochemical studies revealed that alanine aminotransferase levels changing first during short action (30 injections) of lead sulfide nanoparticles of size 10 and 30 nm, and the ionic form of a 400 nm lead while the growth of both enzymes (aspartate aminotransferase and alanine aminotransferase) activity during long-term exposure (60 injections) is the same intensity. It it confirmed by the value of de Ritis coefficient, which is statistically the same as control. Morphological studies also confirm these data--degenerative changes of hepatocytes, reactive changes of the stroma and vascular responses were detected. It is shown that the severity of metabolic and morphological damages in the liver increased with prolonging the duration of lead nanoparticles intake.

[A method of determining allergic changes in leukocytes]. / Sposob opredeleniia allergicheskoi al'teratsii leikotsitov.

The new technique for the detection of hypersensitivity to allergens is based on the fact that after 2 hrs incubation of citrate blood with the allergen the leukocytes are destroyed and K ions leave the cell. Potassium level in the supernatant is measured by flame photometry. This method has been tried in examinations of 81 patients with pulmonary tuberculosis and aspergillosis and 18 healthy donors. The method has proved to be specific and informative for the detection of tuberculin and fungal allergy. It is less labor-consuming than the determination of the neutrophil injury index and more objective, since its results are recorded instrumentally.

Macrophage-lymphocyte interaction in the formation of delayed-type hypersensitivity.

Macrophage-lymphocyte interaction was studied on 121 CBA mice during a 2-hour contact of lymph-node cells of non-immune mice with a monolayer of peritoneal macrophages of BCG-immunized mice and subsequent intravenous administration of 4.10(7) pre-incubated lymphocytes to syngenic recipients. Sensitivity to tuberculin was demonstrated in the recipients by means of blast-transformation reaction of spleen cells (stimulation index was evaluated according to incorporation of 3H-thymidine--SI = 1.32 +/- 0.40) using administration of tuberculin into the paws (Mantoux reaction--MR = 0.11 +/- 0.02 mm) and the cytotoxic effect (CTE) of the lymphocytes on tuberculin-loaded sheep-cell erythrocytes whose disintegration was assessed according to discharge of iron from the target cells (CTE = 13.98 +/- 2.73%). At transfer of intact lymphocytes after contact with non-immune macrophages, SI = 1.046 +/- 0.019; MR = 0.014 +/- 0.002 mm; CTE = 0.214 +/- 0.048%. The treatment of lymphocytes with indomethacin during the contact with macrophages induced idvere changes in the indices of delayed-type hypersensitivity (DTHS). The conclusion has been drawn that the antigen-presenting ability of macrophages can materialize in vitro.