Search

The possibility of the formation of high entropy single-phase perovskites using solid-state sintering was investigated. The BaO-SrO-CaO-MgO-PbO-TiO 2 , BaO-SrO-CaO-MgO-PbO-Fe 2 O 3 and Na 2 O-K 2 O-CaO-La 2 O 3 -Ce 2 O 3 -TiO 2 oxide systems were investigated. The optimal synthesis temperature is found between 1150 and 1400 °C, at which the microcrystalline single phase with perovskite structure was produced. The morphology, chemical composition, crystal parameters and dielectric properties were studied and compared with that of pure BaTiO 3 . According to the EDX data, the single-phase product has a formula of Na 0.30 K 0.07 Ca 0.24 La 0.18 Ce 0.21 TiO 3 and a cubic structure., Competing Interests: The authors declare no conflict of interest.

Crystalline high-entropy single-phase products with a magnetoplumbite structure with grains in the μm range were obtained using solid-state sintering. The synthesis temperature was up to 1400 °C. The morphology, chemical composition, crystal structure, magnetic, and electrodynamic properties were studied and compared with pure barium hexaferrite BaFe 12 O 19 matrix. The polysubstituted high-entropy single-phase product contains five doping elements at a high concentration level. According to the EDX data, the new compound has a formula of Ba(Fe₆Ga 1.25 In 1.17 Ti 1.21 Cr 1.22 Co 1.15 )O 19 . The calculated cell parameter values were a = 5.9253(5) Å, c = 23.5257(22) Å, and V = 715.32(9) ų. The increase in the unit cell for the substituted sample was expected due to the different ionic radius of Ti/In/Ga/Cr/Co compared with Fe 3+ . The electrodynamic measurements were performed. The dielectric and magnetic permeabilities were stable in the frequency range from 2 to 12 GHz. In this frequency range, the dielectric and magnetic losses were -0.2/0.2. Due to these electrodynamic parameters, this material can be used in the design of microwave strip devices.

The development of metacercariae of Diplostomum pseudospathaceum Niewiadomska, 1984 is accompanied by profound morphological transformations often characterized as metamorphosis, which makes these metacercariae an interesting case for studying the morphogenesis of the digenean nervous system. Although the nervous system of D. pseudospathaceum is one of the most extensively studied among digeneans, there are still gaps in our knowledge regarding the distribution patterns of some neuroactive substances, most notably neuropeptides. The present study addresses these gaps by studying pre-infective metacercariae of D. pseudospathaceum using immunochemical staining and confocal microscopy to characterize the distribution patterns of serotonin (5-HT) and two major groups of flatworm neuropeptides, FMRFamide-related (FaRPs) and substance P-related (SP) peptides. The general morphology of the nervous system was examined with antibodies to alpha-tubulin. The nervous system of the metacercariae was shown to conform to the most common morphology of the nervous system in the hermaphroditic generation, with three pairs of posterior nerve cords and four pairs of anterior nerves. The patterns of FaRP- and 5-HT immunoreactivity (IR) were similar to those revealed in earlier studies by cholinesterase activity, which is in accordance with the known role of these neurotransmitters in controlling muscle activity in flatworms. The SP-IR nervous system was significantly different and consisted of mostly bipolar cells presumably acting as mechanoreceptors. The architecture of the nervous system in D. pseudospathaceum metacercariae is discussed in comparison to that in cercariae of D. pseudospathaceum and metacercariae of related digenean species.

Lipopolysaccharide (LPS) administration in an in vivo experimental mice model causes oxidative damage in the liver, muscle, and kidney. We aimed to determine specific mechanisms underlying melatonin's antioxidant protective role. Assays were carried out in quadruplicate in the control, melatonin (10 mg/kg, 10 days), acute LPS administration (once 150 μg), and LPS + melatonin groups. LPS stimulated lipid peroxidation processes (dienes and malondialdehyde) and antioxidant enzyme concentrations (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) were assessed in all investigated tissues. Protein oxidation processes (measured as aldehyde and kenotic carbonyl protein derivatives) were enhanced by LPS in the kidney and liver but not in muscle. Melatonin reversed LPS-induced changes, with the exception of muscle protein oxidation. LPS-induced oxidative stress resulted in augmented early-stage diene conjugated and end-stage malondialdehyde lipid peroxidation processes and affected antioxidant activity in liver, kidney, and muscle tissues. LPS activated protein oxidation processes in the kidney and liver. Melatonin ameliorated oxidative damage in the liver, kidney, and partially in the muscle. Melatonin modulates oxidative stress-induced states. Potential synergism between melatonin and systemic inflammation in terms of oxidative modification of muscle proteins needs to be clarified in further studies.

The aim of the study was to elucidate the effects of melatonin administration (10 mg/kg, 10 days) in a model of inflammation and oxidative stress induced by low-dose bacterial lipopolysaccharide (LPS, once 150 μg). Assays were carried out in quadruplicate in the control, melatonin (10 mg/kg, 10 days), acute LPS administration (once 150 μg) and LPS plus melatonin groups. Blood morphological examination was performed. Erythrocyte resistance to haemolytic agents, ceruloplasmin, diene conjugates, malondialdehyde, oxidatively modified protein concentrations, total antioxidant capacity and antioxidant enzyme activity in plasma were measured. LPS administration in mice resulted in white blood cell (WBC) depletion, erythrocyte cell membrane impairment and oxidative stress in plasma characterised by lipid and protein oxidative processes, decreased antioxidative defence and augmented ceruloplasmin concentrations. Melatonin treatment provided to LPS-exposed animals restored WBC counts, ameliorated erythrocyte membrane damage and decreased overall oxidative stress in plasma. Melatonin provides multilevel protection in animals exposed to low-dose LPS.

The aim of this study was to determine the effects of long-term administration of the oral antidiabetic metformin or the pineal hormone melatonin, and a combination thereof, in preventing oxidative stress in the heart tissue of female Sprague-Dawley rats with mammary tumors induced by N-methyl-N-nitrosourea (NMU) (50 mg/kg) given on the 42nd postnatal day. Metformin and melatonin were administered 12 days before and 16 weeks after the carcinogen. During the experiment, all animals were fed a high fat diet (10% total fat, 2.5% from lard, and 7.5% from palm oil). The findings are that mammary carcinogenesis generated oxidative stress. Reactive oxygen species (ROS) content, estimated from thiobarbituric acid reactive substances (TBARS), oxidatively modified protein content (aldehyde and ketone derivatives), and the activity of the antioxidant enzymes superoxide dismutase, glutathione reductase, and glutathione peroxidase were all augmented. Metformin caused a decrease in oxidative stress in the heart, accompanied by a decrease in diene conjugates, the elimination of ROS (stable total antioxidant status), and the activation of catalase and glutathione reductase. Melatonin caused an increase in total antioxidant status and a substantial reduction in ROS as estimated from aldehyde and ketone derivatives, lipid peroxidation at the initial (diene conjugates) and terminal stages (TBARS), and increased catalase and glutathione peroxidase activities. Metformin and melatonin combined reversed the effects of NMU on oxidative stress. In conclusion, melatonin reduces the level of oxidative stress in the heart tissue, caused by NMU carcinogenesis and a high fat diet, significantly stronger than metformin.

The first comparative study of the polychaete pygidial region has been performed using confocal scanning microscopy and immunohistochemical methods. Fundamentally new data has been obtained on the pygidial organization in representatives the Nephtyidae and Syllidae families. Despite differences in the overall morphology of pygidium, it is characterized by a certain structural plan as a whole that can be the basis for that of all polychaetes. Some insignificant differences in the pygidial structure can be either species-specific or consequences of mutations and seem to have no fundamental importance for the general organization.

The nervous system structure was compared for the first time in avicularia and vibracula in seven species of the cheilostome bryozoans from six families by immunohistochemical methods and confocal scanning microscopy. Regardless of significant differences in heterozooid shape, size, and position in a colony, their muscular and nervous systems have a common structure, which suggests their parallel evolution.

In the White Sea bryozoans Arctonula arctica, the structure of the nervous system and distribution of 5-hydroxytryptamine (5-HT) and FMRF-amide were studied for the first time using immunohistochemical methods and confocal scanning microscopy. The neurotransmitters studied have been actively involved into the integrative processes, gut functioning, and regulation of motion activity. In avicularia, 5-HT and FMRF-amide receptors are capable of performing the same functions, except for participation in the gut functioning, because they have no digestive system.

This work is devoted to the study of the features of oxidative metabolism of hepatocytes in diabetic mice and those under the vitamin D3 action. We found out that a 2.5-fold decrease of 25OHD3 content in the serum was caused by chronic hyperglycemia in diabetes. Intensification of the reactive oxygen species (ROS) and nitrogen monoxide (NO) production, protein oxidative modifications (detected by the contents of carbonyl groups and 3-nitrotyrosine), accumulation of diene conjugates and TBA-reactive products of lipid peroxidation, and the decreased level of free SH-groups of low molecular weight compounds in the liver were accompanied by development of vitamin D3 deficient state. It was shown that there was a decrease in the key antioxidant enzymes activity (catalase, SOD), while the activity of prooxidant enzymes, Nad(p)h: quinone oxidoreductase, xanthine oxidase and NAD(P)H oxidase was increased. The identified oxidative metabolism lesions caused the elevation of the hepatocytes necrotic death that was tested for the ability of their nuclei to accumulate propidium iodide. Prolonged vitamin D3 administration (during 2 months) at a dose of 20 IU to diabetic mice helps to reduce the ROS formation and biomacromolecules oxidative damage, normalizes the antioxidant system state in the liver and increases survival of hepatocytes. The results suggest that vitamin D3 is a key player in the regulation of the oxidative metabolism in diabetes.

This review focuses on the analysis of diagnostic value of the major bone remodeling markers, in particular synthesis and degradation markers of collagen type I. These include carboxy- and aminoterminal telopeptide, carboxy- and aminoterminal propeptide of procollagen type I, hydroxyproline, hydroxylysine, pyridinoline and deoxypyridinoline. Their measurement allows evaluating the structural and functional conditions and also the rate of metabolic processes in the bone tissue. The advantages and disadvantages of determination of these markers in the condition of different bone diseases were examined. It is shown that determination of bone collagen type I metabolism markers is the most informative for assessment of bone resorption, formation and turnover.

A variety of lipid radicals are formed under oxidative stress development. The further oxidation of these radicals leads to formation of numerous aldehydes. They can form postsynthetic modifications in proteins and nucleic acids that disrupt their functions. In the present study aldehydes role in the formation of oxidative stress parameters in rat thymocytes was investigated. Two models were used: iron-stimulated oxidative stress and exogenous aldehydes exposure to thymocytes. For oxidative stress induction, thymocytes (2 x 10(6) cells/ml HBSS, pH 7.2) were exposed to different concentrations of FeSO4 (20, 30, 40 microM) and ascorbic acid (100 microM) for 6 h. It resulted in increase of levels of aldehydes 29 times (90 +/- 6 nmol/10(7) cells), these changes led to increase of TBARS levels 4.4 times; the levels of protein CO groups 10 times, cell mitochondrial activity and low-molecular weight SH groups were decreased 1.5 and 2.3 times, respectively. Treatment with aldehydes acceptor dimedone (200 microM) significantly decreased the levels of aldehydes 3.7 times, TBARS 1.6 times and protein CO groups 5 times. It was shown that the levels of cell mitochondrial activity increase 1.4 times and the levels of SH groups 1.8 times. To compare the effects of aldehydes in induction of oxidative stress, thymocytes (2 x 10(6) cells/ml HBSS, pH 7.2) were exposed to 50-600 microM formaldehyde (FA), 50-600 microM glyoxal (GL), 50-600 microM methylglyoxal (MGL), 1-15 microM acrolein (ACR) for 6 h. TBARS levels were increased for FA 1.3 times and for other aldehydes about 5-7 times. The levels of protein CO groups were increase for FA 3.7 times, for MGL 7 times, for GL 13 times, for ACR 22 times. Levels of SH groups were decreased for FA 1.5 times, for MGL 2.6 times, for GL 3 times, for ACR 9 times. A decrease of cell mitochondrial activity 1.5 times observe for all aldehydes. Obtained results prove the aldehydes participation in the formation of oxidative stress parameters and their capability to oxidative stress induction in the rat thymocytes.

The system of muscle fibers associated with the brain and lateral nerve cords is present in all major groups of enoplan nemerteans. Unfortunately, very little is known about the functional role and spatial arrangement of these muscles of the central nervous system. This article examines the architecture of the musculature of the central nervous system in two species of monostiliferous nemerteans (Emplectonema gracile and Tetrastemma cf. candidum) using phalloidin staining and confocal microscopy. The article also briefly discusses the body-wall musculature and the muscles of the cephalic region. In both species, the lateral nerve cords possess two pairs of cardinal muscles that run the length of the nerve cords and pass through the ventral cerebral ganglia. A system of peripheral muscles forms a meshwork around the lateral nerve cords in E. gracile. The actin-rich processes that ramify within the nerve cords in E. gracile (transverse fibers) might represent a separate population of glia-like cells or sarcoplasmic projections of the peripheral muscles of the central nervous system. The lateral nerve cords in T. cf. candidum lack peripheral muscles but have muscles similar in their position and orientation to the transverse fibers. The musculature of the central nervous system is hypothesized to function as a support system for the lateral nerve cords and brain, preventing rupturing and herniation of the nervous tissue during locomotion. The occurrence of muscles of the central nervous system in nemerteans and other groups and their possible relevance in taxonomy are discussed., (Copyright © 2012 Wiley Periodicals, Inc.)

Detailed comparative-histological data on localization and morphological peculiarities of catecholamine-, serotonin-, neurotensin- and FMRFamide-containing elements in the nemertine digestive system are presented for the first time. Using fluorescent histochemistry and immunohistochemistry, pharynx, esophagus, and midgut were studied in five species from three genera of the White Sea nemertines. Described in various nemertine species are intra- and subepithelial cells of the open and closed type, containing biologically active substances. Their processes are distributed in basi- and subepithelial nerve plexuses and can make contact with lumen of the digestive tract. Species-specificity in localization of the cells containing certain biologically active substances is noticed both along the length of the tract and with respect to its epithelial layer. Peculiarities and common regularities in distribution are discussed, as well as a possible function of monoamine- and peptide-containing elements in the digestive tract of the studied nemertines and other invertebrates.

A variety of common histological stains was used, along with the Golgi and Colognier silver impregnation methods and electron microscopy, to perform a comparative study of the morphological characteristics of receptor and nerve cells and their interactions in the nervous system of the wall of the mantle cavity and mantle derivatives - gills, siphon, and osphradia - of the marine prosobranch gastropod mollusks Buccinum undatum and Littorina littorea. The results are discussed along with our own previously obtained data on the organization of the osphradial sensory organs and the afferent elements of the mantle cavity wall in other prosobranch mollusks - the terrestrial Pomatia elegans and the freshwater Viviparus contectus and Pomacea paludosa. Using the nervous system of the complex of mantle organs of prosobranch mollusks as examples, the structural features and evolutionary trends of the afferent part of the visceral nervous system of gastropods are discussed.

Interferon homeostasis was studied in children with bronchial asthma (BA) at different stages of the disease. The control group consisted of 10 children with no predisposition to atopic reaction. Children with BA showed a disfunction of interferon homeostasis, with a significant decline in the leukocyte ability to produce IFN-alpha and IFN-gamma. The concentration of blood serum IFN-gamma was reduced at all stages of BA, with a more significant decrease during BA attacks than during the remission period. IFN-gamma synthesis disturbances in BA children were stable and resistant to therapeutic treatment by recombinant IFN-alpha2b (Viferon). Viferon normalized the production of IFN-alpha, and the effect remained unchanged during a half-year examination period. Thus, Viferon appears promising as part of a complex therapy for children with BA at remission stages and frequent respiratory infections.

The author's data on the structural organization of the nervous system of the body wall, the gravitational organs (the statocysts, the eyes, and the chemosensory organs), and the head tentacles of the snails Helix vulgaris and Helix pomatia are correlated in this paper. The localization in the CNS and some structural characteristics of the central divisions of the sensory systems are shown. Information is presented on the structure of the procerebrum, an associative center participating in the processing of chemosensory information. The data were obtained using the Golgi method, the retro- and anterograde transport of CoCl2, horseradish peroxidase, and lucifer yellow, as well as a number of other classical histological methods.

The synthesis of virus-specific macromolecules was studied in the reconstituted system containing inner membrane-matrix fraction from rat liver mitochondria and infectious RNA of Venezuelian equine encephalomyelitis (VEE) virus. In a series of preliminary experiments it was shown that isolated submitochondrial fraction was completely free of interfering cytoplasmic contaminations and particularly, of cytoplasmic 80S ribosomes. VEE RNA when added to submitochondrial system caused significant stimulation of RNA and protein synthesis. These processes were resistant to actinomycin D which inhibited profoundly the synthesis of proper mitochondrial macromolecules. The stimulating effect of VEE RNA in experiments with submitochondrial system was about three times higher than that with intact mitochondria. The stimulation of 14C-amino acid incorporation increased as a function of incubation time; a certain lag-period being observed. The newly formed virus-specific RNA's and ribonucleoproteins were identified with the aid of sedimentation analysis. In particular, radioactive RNA's with sedimentation coefficients 40S and 26-18S were isolated from the incubated system. These RNA's are similar respectively to VEE genome RNA and double-stranded VEE replicative RNA. In double labelling experiments with 3H-uridine and 14C-amino acids it was shown that VEE RNA induced synthesis of ribonucleoproteins containing newly formed RNA and protein. These RNP possessed sedimentation coefficients 60-80S, 140S and 300S in sucrose gradient and buoyant densities 1.32 and 1.50 g/cm3 in cesium chloride gradients. These properties of ribonucleoproteins synthesized de novo in submitochondrial system are close to those of RNP intermediates of VEE virus reproduction in the infected cells. We concluded that viral RNA could program virus-specific synthesis in the submitochondrial system under conditions that eliminated the contribution of cytoplasmic ribosomes.