Research of nickel nanoparticles toxicity with use of Aquatic Organisms

The effect of nanoparticles with the particle size Δ50=5 nm on the test function of aquatic organisms was analyzed by means of biotesting methods with the use of a complex of test-organisms representing general trophic levels. The dependence of an infusoria Paramecium caudatum chemoattractant-elicited response, unicellular algae Сhlorella vulgaris Beijer growth rate, Daphnia magna Straus mortality and trophic activity and Danio rerio fish kill due to nNi disperse system concentration, is estimated. It is determined that the release of chlorella into cultivated environment including nNi as a feed for daphnias raises the death rate of entomostracans. The minimal concentration, whereby an organism response to the effect of nNi is registered, depends on the type of test organism and the analysed test function. L(E)С20 is determined for all the organisms used in bioassays. L(E)С50 is estimated for Paramecium caudatum (L(E)С50 = 0.0049 mg/l), for Сhlorella vulgaris Beijer (L(E)С50 = 0.529 mg/l), for Daphnia m. S (L(E)С50 > 100 mg/l) and for fish Danio rerio (L(E)С50 > 100 mg/l). According to the Globally Harmonized System hazard substance evaluation criteria and Commission Directive 93/67/EEC, nNi belongs to the “acute toxicity 1” category of toxic substances

Evaluation of the toxicity of superfine materials to change the physiological functions of aquatic organisms of different trophic levels

We assessed ecological and biological effects caused by the physical and chemical properties of nanomaterials on the basis of the laboratory researches into water test-organisms of different trophic levels. We studied the physiological functions of water organisms on adding into the environment superfine materials of various chemical nature and structural characteristics: metallic nanoparticles of nikel (nNi), argentum (nAg), platinum (nPt), aurum (nAu), binary NPs (powder of titanium dioxide - nТiO2, aluminum oxide - nAl2O3, zink oxide - nZnO, silicon nitride - nSi3N4, silicon carbide (nSiC) and carbon nanotubes (ВТ-50, MCD-material). We observed the dependence of developing the complex of unfavourable biological effects in water plants and entomostracans’ organisms on the physical and chemical properties of superfine materials. We determined the values of NOEC, L(E)С20 and L(E)С50 for aquatic organisms of various regular groups. We found out the most vulnerable elements of the communities’ trophic structure and the possibility of a breakdown in the water ecosystem food pyramid

Biophotonics approach for the study of leukocyte activation

Leukocytes are the main cells of immune system, but also contribute to other systems and participate in pathogenesis of different diseases. In particular, leukocytes are involved in the progression of diabetic retinopathy due to their hyperactivation in diabetes. However, a connection between diabetes and the dysfunction of leukocytes is poorly understood. For a more complete picture, studies of the leukocytes activation under the influence of various substances are necessary. Arachidonic acid (AA) and its metabolites are the strongest activating factors of leukocytes. However, the studies involving AA are complicated because it is water-insoluble. Here we describe the method to study activation using photolabile analogs of AA

Effect of AL2O3 and TiO2 nanoparticles on aquatic organisms

Environmental toxicity of aqueous disperse systems of nanoparticles of binary compounds of titanium dioxides (with particle size Δ50=5 nm, Δ50=50 nm, Δ50=90 nm), aluminum oxide alpha-forms (Δ50=7 nm and Δ50=70 nm) and macro forms (TiO2 Δ50=350 nm, Al2O3 Δ50=4000 nm) were studied using biological testing methods. The bioassay was performed using a set of test organisms representing the major trophic levels. We found the dependence of the toxic effect concentration degree of nTiO2 and nAl2O3 on the fluorescence of the bacterial biosensor "Ekolyum", the chemotactic response of ciliates Paramecium caudatum, the growth of unicellular algae Chlorella vulgaris Beijer and mortality of entomostracans Daphnia magna Straus. We revealed the selective dependence of nTiO2 and nAl2O3 toxicity on the size, concentration and chemical nature of nanoparticles. The minimal concentration causing an organism’s response on nTiO2 and nAl2O3 effect depends on the type of the test-organism and the test reaction under study. We specified L(E)С50 and acute toxicity categories for all the studied nanoparticles. We determined that nTiO2 (Δ50=5 nm) belong to the category «Acute toxicity 1», nTiO2 (Δ50=90 nm) and nAl2O3 (Δ50=70 nm) – to the category «Acute toxicity 2», nAl2O3 (Δ50=7 nm) - to the category «Acute toxicity 3». No acute toxicity was registered for nTiO2 (Δ50=50 nm) and macro form TiO2

Embryotoxicity of poorly soluble nanoparticles at various stages of Zebrafish development

The biological effects of the poorly soluble nanoparticles (NPs) of different chemical nature and structural characteristics were evaluated. It was established that the Zebrafish test response to contamination of aqueous medium with nickel NPs (nNi), platinum (nPt), zinc oxide (nZnO) and cerium oxide (nCeO2) depends on the physicochemical properties of the NPs and embryo development stage. The concentrations of NPs not causing disruptions in embryonic development of Zebrafish were determined. The smallest impact on embryogenesis was exerted by nCeO2: coagulation of a small number of embryos was observed only at C = 20.0 mg/L. The same effect was observed when exposed to lower concentrations of nPt (C = 5.0 mg/L) and nNi (C = 0.1 mg/L). The greatest number of coagulated embryos was observed when grown in the DS nZnO: 37.5% of embryos died at the DS concentration of C = 0.1 mg/L. Zebrafish cultivation in the DS with low concentrations (C ≤ LC10) of nNi and nZnO caused distortions in the development of embryos: development of scoliosis, malformation of somites, inhibited mobility

Conjugates of a Photoactivated Rhodamine with Biopolymers for Cell Staining

Conjugates of the photoactivated rhodamine dyes with biopolymers (proteins, polysaccharides, and nucleic acids) are important tools for microscopic investigation of biological tissue. In this study, a precursor of the photoactivated fluorescent dye (PFD) has been successfully used for staining of numerous mammalian cells lines and for conjugate formation with chitosan (“Chitosan-PFD”) and histone H1 (“Histone H1.3-PFD”). The intensive fluorescence has been observed after photoactivation of these conjugates inside cells (A431, HaCaT, HEK239, HBL-100, and MDCK). Developed procedures and obtained data are important for further application of novel precursors of fluorescent dyes (“caged” dyes) for microscopic probing of biological objects. Thus, the synthesized “Chitosan-PFD” and “Histone H1-PFD” have been successfully applied in this study for intracellular transport visualization by fluorescent microscopy

Changes in the plasma levels of myokines after different physical exercises in athletes and untrained individuals

The influence of dynamic and static load on the plasma level of myokines in strength-and endurance-trained athletes and untrained subjects has been studied. The range of myokines has been found to depend on the type of loads and the level of fitness. Dynamic and static exercises have different effects on the level of myokines in athletes and untrained subjects. The dynamic load increases the level of IL-6 and IL-8 in the plasma of athletes, while the static load increases the concentration of IL-15 and LIF. At the same time, no increase in the level of IL-8 after cyclic loading or in IL-15 after a static load has been observed in the control group. These differences may be based on a number of mechanisms. The cellular composition of skeletal muscles and the phenotypic features of muscle fibers, changing as a result of regular exercise, can modify the processes of myokine production. However, the processes of transcription in muscle fibers are much more important; the most important ones are HIF-1α, [Ca2+]i and [Na+]i/[K+]i-dependent intracellular signaling pathways. The modification of these mechanisms caused by different physical loads and intensity is of great interest since it is a promising way to influence the metabolic processes at the cellular and systemic levels, which is very helpful in both improving athletic performance and correcting metabolic disorders in a number of socially significant diseases

Glyproline Pro-Ampakine with Neuroprotective Activity

Previously it was shown that neuropeptide cyclo-L-prolylglycine (CPG) is a positive modulator of AMPA receptors, which increases BDNF level in neuronal cell cultures. The spectrum of CPG’s pharmacological effects corresponds to that of BDNF. Dipeptide N-phenylacetyl-glycyl-L-proline ethyl ester (GZK-111) was designed and synthesized as a linear analog of CPG. The aim of the present work was to reveal the pharmacological profile of GZK-111. Dipeptide GZK-111 was shown to metabolize into CPG in vitro and increased cell survival by 28% at concentrations of 10-7–10-6 M in a Parkinson’s disease cell model. In a model of cerebral ischemia, GZK-111, at a dose of 0.5 mg/kg, i.p., was found to have neuroprotective effects, reducing the cerebral infarct volume by 1.6 times. Similar to CPG, GZK-111, at the range 0.1–1.0 mg/kg, i.p., possessed a stereospecific antiamnesic activity. A significant anxiolytic effect was observed at a dose of 1.5 mg/kg. GZK-111, at the range 0.5–4.0 mg/kg, i.p., demonstrated analgesic activity. GZK-111, at a dose of 10 mg/kg/7 days, i.p., possessed antidepressant-like activity. So, the neuroprotective, nootropic, antihypoxic, anxiolytic, antidepressant-like, and analgesic effects of GZK-111 were revealed. Thus, GZK-111 can be considered as a pharmacologically active pro-ampakine with a BDNF-ergic mechanism of action

Annulation of Perimidines with 5-Alkynylpyrimidines en Route to 7-Formyl-1,3-Diazopyrenes

Unusual rearrangements were shown to accompany Brønsted acid-assisted peri-annulations of 1H-perimidines with 5-alkynylpyrimidines. These transformations take different routes depending on the nature of acetylene precursor, and lead to the formation of 7-formyl-1,3-diazopyrenes

Phototropic response features for different systematic groups of mesoplankton under adverse environmental conditions

Current trends in the application of bioindication methods are related to the use of submersible tools that perform real- time measurements directly in the studied aquatic environment. The methods based on the registration of changes in the be- havioral responses of zooplankton, in particular Crustaceans, which make up the vast majority of the biomass in water areas, seem quite promising. However, the multispe- cies composition of natural planktonic biocenoses poses the need to consider the potential difference in the sensitivity of organisms to pollutants. This paper describes laboratory studies of the phototropic response of plankton to attracting light. The studies were carried out on a model natural community that in equal amounts includes Daphnia magna, Daphnia pulex, and Cyclops vicinus, as well as on the monoculture groups of these species. The phototropic response was initiated by the attracting light with a wavelength of 532 nm close to the local maximum of the reflection spectrum of chlorella microalgae. Standard potassium bichromate was used as the model pollutant