Errata Corrige: Stress-Induced Phosphorylation of C-Jun-N-Terminal Kinases and Nuclear Translocation of Hsp70 in the Wistar Rat Hippocampus (Vol 61, Pg 1, 2009)

In the paper entitled: Adžić, M., Đorđević, A., Krstić-Demonacos, M., & Radojčić, M. B. (2009). Stress-induced phosphorylation of c-Jun-N-terminal kinases and nuclear translocation of Hsp70 in the Wistar rat hippocampus. Archives of Biological Sciences, 61(1), 1-8. Fig. 1, on page 4, section b, should read "Nucleus" instead of "Cytoplasm

Independent associations of childhood and current socioeconomic status with risk of self-reported doctor-diagnosed arthritis in a family-medicine cohort of North-Carolinians

Most experimental models, including cell culture studies, have demonstrated that over-expression of manganese superoxide dismutase (MnSOD) in cells bearing a carcinoma phenotype has anti-proliferative and tumour suppression characteristics. In contrast, when cervical carcinoma biopsies express MnSOD, there is a poor prognosis and resistance to radiation therapy. The results herein indicate that human cervical adenocarcinoma (HeLaS3) cells have increased MnSOD activity (up to 50 % of the total SOD activity) due to low expression of its repressor p53 and a high level of oxidative stress arising from the cell culture conditions. High MnSOD activity may be related to I-IcLaS3 cell radioresistance. illustrated by a high IC50 of 3.4 Gy and by a relatively high level of cell viability after gamma irradiation. In contrast to MnSOD activity, cytosolic CuZnSOD activity decreased after ionising radiation. The catalase (Cat) activity was unchanged. IR also increased the nitric oxide synthase (NOS) activity. Such conditions lead to increased concentrations of the superoxide radical, hydrogen peroxide and NO, which together may be responsible for the decreased expression of NF-B-K and unaltered Cat activity. Therefore, the disturbed redox balance within HeLaS3 cells may be responsible for the cytotoxicity observed at higher irradiation doses. It could be concluded that inhibition of the CuZrISOD activity may be an important target for the selective killing of radioresistant cancer cells

Synthesis and characterization of Co2+ doped TiO2 nanoparticles

Scrolled titania nanotubes were synthesized by a hydrothermal method using commercial TiO2 powder in proton-deficient aqueous systems. In presence of CoCl2 extended hydrothermal treatment of TiO2 nanotubes lead to formation Co2+ doped TiO2 nanoparticles. TEM and HRTEM measurement were used for determining the shape, dimension and structure of doped nanoaprticles. XRD confirmed anatase crystalline structure od Co2+ doped TiO2. The presence of Co2+ ions did not induce distortions of the overall anatase crystal structure of TiO2 matrix. The concentration of Co2+ ions was 1.5% compared with the amount of Ti4+ ions.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200

Gamma-radiation induced agglomeration of chicken muscle myosin and actin

Radiolytic behaviour of the major vertebrate muscle proteins: fibril Jar myosin (rnolar mass, M-m = 520,000 g/mol) and filament fortning actin (M-m = 42,050 g/mol) was studied using a SDS-polyacrylamide gel electrophoresis and quantified by high precision laser-densitometry. In order to study the OH radical contribution to the radiation damage, purified chicken myosin and actin (4 muM) were prepared in N2O saturated solution and irradiated with 1-3 kGy at Co-60 gamma source. With respect to changes in the molecular mass, the only observed myosin and actin damage was dose dependent agglomeration of proteins. The corresponding radiation chemical yields of 5 x 10(-8) mol J(-1) and 6.3 x 10(-8) mol J(-1) were obtained for myosin and actin, respectively. This result confirmed that only the radiation-induced agglomeration is initiated with the reaction of the OH radical even in the situation where the OH radical concentration produced exceeds the protein concentration 500 times, thus enabling the multi-radical attack to occur

Gamma-radiation induced damage of proteins in the thick fraction of egg white

The thick fraction of egg white saturated with either N2O or Ar was irradiated in the dose range 1.5-45 kGy at Co-60 gamma source. The gel structure decomposition and other processes accompanied with changes in protein molecular mass were followed by Sephadex G-200 exclusion chromatography, denaturing SDS-polyacrylamide gel electrophoresis, viscosity and turbidity measurements. The complex behaviour of viscosity was observed in the NO saturated sample (where the hydrated electron was converted into the OH radical); the initial abrupt decrease that gradually slows down reaching the minimum at 12 kGy (eta(mm) = 2.7 mPa s) followed by the slow rise was measured. The Ar saturated sample ([e(aq)(-)] approximate to [OH]) showed both the significantly faster initial decrease and lower viscosity minimum (eta(min) = 2.2 mPa s). The combined Sephadex G-200 exclusion chromatography and denaturing SDS-polyacrylamide gel electrophoresis data revealed that the three-dimensional egg white (hydrated) gel structure was (efficiently) decomposed even in the N2O saturated sample. The protein scission was detected in the entire dose range studied, while the protein agglomeration is not noticed at low doses (around 1.5 kGy); however, it dominates at higher doses. In the highest dose region studied, the loss of structure in SDS-PAGE chromatograms indicates that the agglomerates arc formed from protein fragments rather than from intact proteins. The continuous linear increase in turbidity was measured. The results obtained indicate that ionizing radiation causes the breakdown of the protein network of the thick fraction of egg white via the reduction of S S bridges by the hydrated electron and the protein fragmentation due to the direct action of ionizing radiation. The protein agglomeration is initiated by the reaction of the OH radical; its inefficiency at low doses is attributed to the glucose antioxidant properties and radical immobility

Synthesis, characterization and photocatalytic activity of anatase nanoparticles doped with gadolinium ions

Gd3+-doped anatase nanoparticles have been synthesized via acidic hydrolysis of Gd3+ and Ti4+ organic precursors. The resulting products were characterized by Xray diffraction (XRD) and diffuse reflection spectra (DRS). Experimental results indicated that different Gd3+-doping levels make great impact on the optical properties and photocatalytic activity of the obtained TiO2 nanoparticles. All applied doping concentrations induced enhancement of photoactivity regarding degradation of Rhodamine B (RB), compared to pure TiO2. The inter-band defect states formed as a result of incorporation of Gd3+ ions in the TiO2 matrix are most probably the cause of observed improved photoacatalytic activity and optical properties of the doped TiO2 nanoparticles.Physical chemistry 2012 : 11th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 201

TiO2/Ag nanoparticles modified cotton fabric and its application to photocatalysis

In a series researches so far, it has been shown that TiO2 nanoparticles have become the focus of intensive exploration in the field of photocatalysis, as a consequence of their unique properties and potential applications. In order to improve photocatalytic and functional properties of TiO2 nanoparticles, different methods should be used. One of the most effective approaches is capping of nobel metal (Pt, Ag, Au) clusters on nanoparticle surface. Namely, metal clusters act as electron traps and they promote interfacial charge- -transfer processes and reduce undesirable recombination processes on TiO2 nanoparticle surface. As a consequence, photocatalytic efficiency of the system should be improved. The cotton fabric modified by TiO2/Ag nanoparticles was synthesized by in situ photoreduction of Ag+-ions on alanine modified TiO2 colloidal nanoparticles previously deposited onto cotton fabric. Adsorption of Ag+-ions on TiO2 nanoparticle surface was improved by addition of alanine amino-acid. As a result, separation of photoinduced charges is preferred and recombination process is significantly reduced. In order to further improve the efficiency of the system, methyl alcohol was employed as hole-scavenger. Obtained results confirmed the presence of TiO2/Ag nanoparticles across the surface of cotton fabric (SEM), as well as successful fabrication of metallic Ag on investigated fabric (XRD). Interaction between alanine modified TiO2 and Ag nanoparticles was studied by FTIR, while structural properties of synthesized samples were investigated by Raman spectroscopy. The photocatalytic performance of TiO2/Ag nanoparticles modified cotton fabric was tested in the process of photodegradation of organic dyes under simulated solar light: Rhodamine B, Acid Orange 7 and Methyl Red.Seventeenth Young Researchers' Conference Materials Sciences and Engineerin

Stress-Induced Phosphorylation of C-Jun-N-Terminal Kinases and Nuclear Translocation of Hsp70 in the Wistar Rat Hippocampus

Glucocorticoids are key regulators of the neuroendocrine stress response in the hippocampus. Their action is partly mediated through the subfamily of MAPKs termed c-jun-N-terminal kinases (JNKs), whose activation correlates with neurodegeneration. The stress response also involves activation of cell protective mechanisms through various heat shock proteins (HSPs) that mediate neuroprotection. We followed both JNKs and Hsp70 signals in the cytoplasmic and nuclear compartments of the hippocampus of Wistar male rats exposed to acute, chronic, and combined stress. The activity of JNK1 was decreased in both compartments by all three types of stress, while the activity of cytoplasmic JNK2/3 was elevated in acute and unaltered or lowered in chronic and combined stress. Under all stress conditions, Hsp70 translocation to the nucleus was markedly increased. The results suggest that neurodegenerative signaling of JNKs may be counteracted by increase of nuclear Hsp70, especially under chronic stress

Synthesis and characterization of conducting polyaniline nanotubes in the presence of colloidal TiO2 nanoparticles

Conducting polyaniline nanotubes were synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in water, in the presence of colloidal TiO2 nanoparticles of an average diameter ~5 nm. Polyaniline-TiO2 nanocomposite has been characterized by the electrical conductivity measurements, thermogravimetric analysis, FTIR spectroscopy, scanning and transmission electron microscopies. The electrical conductivity of synthesized nanocomposite was 1.1 × 10–3 S cm–1, slightly higher than that of pure polyaniline prepared under the same conditions. Polyaniline nanotubes have an outer diameter of 45–230 nm nm, an inner diameter of 15–130 nm, and a length extending from 0.5 to 2.0 μm.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200

Western blot analysis of glucocorticoid receptor phosphoisoforms by one- and two-dimensional electrophoretic assays

The glucocorticoid receptor (GR) protein is a cytosolic ligand-dependent transcription factor with numerous functions regulated by post-translational modifications, including phosphorylation/dephosphorylation. Among the functions most extensively affected by GR phosphorylation are the modulation of its transcriptional activity, alterations in its interaction pattern with cofactors, nuclear translocation and selective gene transactivation. Intensive analysis of the intracellular distribution of GR phosphoisoforms and their interaction with proteins of other cellular signalling networks required the use of [gamma-(32)P]ATP as a phosphate donor, and special laboratory protection measures to avoid external irradiation and contamination. In the present study, simple and easy-to-use non-radioactive protein mobility shift assays (NMS assays) were developed using one- and/or two-dimensional gel electrophoresis based on differences in the pI and molecular mass of GR phosphoisoforms. The GR isoforms were immunodetected with specific monoclonal or polyclonal anti-GR antibodies by Western blot in three diverse systems, namely yeast BJ2168 cells expressing wild-type rat GR, rat hepatoma GRH2 cells grown in culture and brain tissue from Wistar rat experimental animals. The results obtained using the NMS assay were similar to previous results obtained with the [gamma-(32)P] ATP standard assay