Regulation of antioxidant enzyme activities in female rat brain by ovarian steroids

The sex steroids produce their effects by acting on numerous target tissues and organs, such as the reproductive organs, bone tissue and cartilage, peripheral blood vessels as well as the central nervous system (CNS). In our studies we have monitored the change of enzyme activity of the antioxidant (AO) system in the brain of female rats depending on the ovarian steroids. We have chosen it as a new parameter that might represent an important indicator of the changes within the CNS, bearing in mind the biological importance of the enzymes of the AO system. The experimental results of our study indicate that the enzyme activity of the AO system in the brain tissue of female rats shows a certain dependence on the concentration of ovarian hormones, progesterone and estradiol, in the organism. Study of the activity of the enzymes of the AO system in the brain of female rats depending on the influence of ovarian hormones can answer whether the action of ovarian steroids on the CNS includes maintenance of a dynamic equilibrium of free radicals in the neurons

Biochemical and ultrastructural changes in the liver of European perch (Perca fluviatilis L.) in response to cyanobacterial bloom in the Gruža reservoir

We investigated the biochemical and ultrastructural changes in the liver of the freshwater fish, European perch (Perca fluviatilis), in response to Aphanizomenon flos-aquae bloom in the Gruža Reservoir, Serbia. The activities of total manganese- and copper zinc-containing superoxide dismutase (Tot SOD, Mn-SOD, Cu/Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and biotransformation phase II enzyme glutathione-S-transferase (GST), as well as concentrations of total glutathione (GSH) and sulfhydryl (-SH) groups were examined before and during the bloom period. Mn-SOD activity was significantly higher, while the activities of Cu/Zn-SOD, CAT and GSH-Px and the concentration of the -SH groups were significantly lower during the bloom. The ultrastructure of the liver revealed necrotic and apoptotic damage to the hepatocytes during the bloom period. Our work represents the first study to report the influences of an Aphanizomenon flos-aquae bloom in the Gruža Reservoir on antioxidant biomarkers and on histopathological alterations in the liver of the freshwater fish European perch (Perca fluviatilis)

Bioimaging of liver cancer cells incubated with partially reduced graphene oxide

Functional materials based on graphene oxide (GO) and reduced graphene oxide (rGO) have a high potential for application in the fields of biophysics, material science, and biomedical engineering [1]. It is due to their tunable physical properties, high surface area, remarkable photoluminescence, as well as their controllable chemical functionalization [2]. Beyond their applications in nanomedicine for drug/gene delivery, phototherapy and bioimaging, they have shown significant interaction and adhesive properties with proteins, mammalian cells and microorganisms, which makes them potential candidates for multifunctional biological applications. In this lecture, we will present a study of the interaction of partially reduced graphene oxide (prGO) with Huh7.5.1 liver cancer cells. The study was conducted by means of synchrotron excitation DUV fluorescence bioimaging (performed on DISCO beamline of synchrotron SOLEIL) [3]. The prGO sample was obtained by the reduction (to a certain extent) of the initially prepared GO nanosheets. The fluorescence of the GO nanosheets increases with time of the reduction due to a change in the ratio of the sp2 and sp3 carbon sites, and the prGO sample was extracted from the dispersion when the intensity of the fluorescence reached its maximum. After that, Huh7.5.1 cells were incubated with GO, prGO and rGO nanosheets and used in bioimaging studies. The presence of graphene materials influenced the fluorescence properties of the cells, and by analyzing fluorescence photobleaching dynamics, we were able to localize graphene nanosheets inside the liver cancer cells.VII International School and Conference on Photonics : PHOTONICA2019 : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 26-30; Belgrad

Glutathione redox status in some tissues and the intestinal parasite Pomphorhynchus laevis (Acanthocephala) from barbel (Barbus barbus) (pisces) from the Danube river

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A fluorescent nanoprobe for single bacterium tracking: functionalization of silver nanoparticles with tryptophan to probe the nanoparticle accumulation with single cell resolution

The investigation of the interaction of silver nanoparticles and live bacteria cells is of particular importance for understanding and controlling their bactericidal properties. In this study, the process of internalization of silver nanoparticles in Escherichia coli cells was followed by means of synchrotron excitation deep ultraviolet (DUV) fluorescence imaging. Antimicrobial nanostructures that can absorb and emit light in the UV region were prepared by functionalization of silver nanoparticles with tryptophan amino acid and used as environmentally sensitive fluorescent probes. The nanostructures were characterized by morphological (TEM) and spectroscopic methods (UV-vis, FTIR, XPS, and photoluminescence). The TEM images and the analyses of the UV-vis spectra suggested that the addition of tryptophan led to the formation of hybrid nanostructures with pronounced eccentricity and larger sizes with respect to that of the initial silver nanoparticles. The DUV imaging showed that it was possible to distinguish the fluorescent signal pertaining to silver-tryptophan nanostructures from the autofluorescence of the bacteria. The spatial resolution of the fluorescence images was 154 nm which was sufficient to perform analyses of the accumulation of the nanostructures within a single bacterium. The DUV imaging results imply that the tryptophan-functionalized silver nanoparticles interact with cell membranes via insertion of the amino acid into the phospholipid bilayer and enter the cells

Antioxidant enzymes and lipid peroxidation in endometrium of patients with polyps, myoma, hyperplasia and adenocarcinoma

<p>Abstract</p> <p>Background</p> <p>Oxidative stress and impaired antioxidant system have been proposed as a potential factors involved in the pathophysiology of diverse disease states, including carcinogenesis. In this study, we explored the lipid peroxidation levels and antioxidant enzyme activities in women diagnosed with different forms of gynecological diseases in order to evaluate the antioxidant status in endometrium of such patients.</p> <p>Methods</p> <p>Endometrial tissues of gynecological patients with different diagnoses were collected and subjected to assays for superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and lipid hydroperoxides.</p> <p>Results</p> <p>Superoxide dismutase activity was significantly decreased (50% in average) in hyperplastic and adenocarcinoma patients. Activities of both glutathione peroxidase and glutathione reductase were increased 60% and 100% on average, in hyperplastic patients, while in adenocarcinoma patients only glutathione reductase activity was elevated 100%. Catalase activity was significantly decreased in adenocarcinoma patients (47%). Lipid hydroperoxides level was negatively correlated to superoxide dismutase and catalase activities, and positively correlated to glutathione peroxidase and glutathione reductase activities.</p> <p>Conclusions</p> <p>This study provided the first comparison of antioxidant status and lipid peroxidation in endometrial tissues of patients with polyps, myoma, hyperplasia and adenocarcinoma. The results showed that patients with premalignant (hyperplastic) and malignant (adenocarcinoma) lesions had enhanced lipid peroxidation and altered uterine antioxidant enzyme activities than patients with benign uterine diseases, polyps and myoma, although the extent of disturbance varied with the diagnosis. Further investigation is needed to clarify the mechanisms responsible for the observed alterations and whether lipid hydroperoxide levels and antioxidant enzyme activities in uterus of gynecological patients might be used as additional parameter in clinical evaluation of gynecological disorders.</p

Sudamérica : un largo camino de conformación geoeconómica

This paper analyzes the reasons and causes behind the impact of Geoeconomy as a new scientific discipline in understanding and interpreting the current state of the world: its diverse and contradictory dynamics and interactions. Within this frame, the author places particular attention on the establishment of LatinAmerican Geoeconomy and its features. In contrast to globalization, which interconnects the world’s main economies, regionalization is making its way in different areas with several degrees of success and in diverse ways, opening the stage to new actors. Latin America’s geoeconomic re-design is here studied within the frame of complex interdependence and the theory of open regionalism. This re-design takes place in different levels: sub-regional, regional, among countries and among groups of countries in different regions.Análisis de las razones y causas que potenciaron el significado de la geoeconomía como nueva disciplina científica para entender e interpretar el mundo actual y sus dinámicas e interacciones —tan diferentes y contradictorias. En este marco se estudia especialmente el nacimiento de la geoeconomía latinoamericana y sus características. A diferencia de la globalización, que interconecta las principales economías del mundo, la regionalización está progresando en diferentes zonas con mayor o menor éxito y de forma desigual, abriendo el espacio para la emergencia de nuevos actores. El rediseño geoeconómico de América Latina es estudiado dentro de los marcos de la interdependencia compleja y la teoría del regionalismo abierto. Dicho rediseño se lleva a cabo en múltiples niveles e implica interacciones subregionales, regionales, con países o grupos de países de otras regiones del mundo

XXI Century: The Formation of the New Geo-economics in Latin America

This paper analyses the formation of New Latin American Geo-economy, starting from establishment of Open Regionalism that was based on neo-liberal reforms applied by the governments of these countries. However, this project entered into profound crisis because of the effects of the contemporary global eco-nomic crisis demonstrating the high level of economic and political vulnerability of the region. In fact, the crisis of neo-liberal development model caused the process of geo-economic and political changes in Latin America pointing to the formation of new progressive process of ideological disagreements concerning the issues of socio-economic development of the region. On the basis of this premises the author suggests considering this problem in the light of the formation of New Latin American Geo-economy at the beginning of the 21st century as a direct consequence of the crisis of neo-liberal model on one side, and Latin American Open Regionalism on the other.En este artículo se analiza el surgimiento de una nueva geoecono-mía latinoamericana a partir de la conformación del regionalismo abierto basado en las reformas neoliberales aplicadas por los gobiernos de estos países. Sin embargo, di-cho proyecto entró en una crisis profunda a raíz de los efectos de la actual crisis eco-nómico-financiera global que demostraron el alto grado de vulnerabilidad económica y política de la región. En realidad, la crisis del modelo neoliberal causó todo un pro-ceso de cambios geoeconómicos y políticos en América Latina indicando la forma-ción de un proceso progresivo de desacuerdos ideológicos en cuanto al desarrollo so-cio-económico de la región. En base a estas premisas el autor sugiere entender el fe-nómeno de la conceptualización de la nueva geoeconomía latinoamericana a princi-pios del siglo XXI como consecuencia directa de la crisis del modelo neoliberal y del regionalismo latinoamericano abierto

Neuroendocrine and Oxidoreductive Mechanisms of Stress-Induced Cardiovascular Diseases

Summary The review concerns a number of basic molecular pathways that play a crucial role in perception, transmission, and modulation of the stress signals, and mediate the adaptation of the vital processes in the cardiovascular system (CVS). These highl