Effects of Acute Administration of D,L-Homocysteine Thiolactone on the Antioxidative Status of Rat Intestine and Liver

Oxidative stress appears to play a role in the pathogenesis of several inflammatory gastrointestinal diseases. Increased homocysteine levels may play a role in the pathogenesis of Chrons disease and ulcerative colitis. The aim of this study was to examine the influence of homocysteine on the antioxidant status of rat intestine and liver. The levels of thiobarbituric acid reactive substances (TBARS), activity of catalase (CAT) and total antioxidant status (TAS) were investigated in the isolated gut and liver of young male rats in the control group (8 rats) and after 3-hour incubation in high doses of D, L-homocysteine thionolactone (Hcy) (10 mu mol/L) (8 rats). Samples of duodenum, ileum, colon and liver were homogenized in sodium phosphate buffer (1: 10). Homogenates were centrifuged at 10000 for 10 min at 4 degrees C and the supernatant was taken for biochemical assays. Our results showed that high D, L-homocysteine thionolactone concentration reduced enzymatic catalase activity in homogenates of the isolated segments of duodenum (27.04%) p LT 0.01; ileum (37.27%), colon (34.17%) and liver (67.46%) p LT 0.001. Exposition to high D, L-homocysteine thiolactone concentration significantly increased TBARS levels in the duodenum (106.05%), ileum (47.24%), colon (112.75%) and liver (32.07%) (p LT 0.01). Homocysteine also modified the total antioxidant status of homogenates from the duodenum, ileum, colon and liver, increasing by 20.68% (duodenum), 24.74% (ileum), 14.88% (colon) and 19.35% (liver) (p LT 0.001). Homocysteine induced a consistent oxidative stress in rats intestine and liver (reduced activity of catalase and increased level of TBARS), but the elevated activity of TAS in our experiments could be explained as an adaptive response to the generated free radicals which indicates the failure of the total antioxidant defense mechanism to protect the tissues from damage caused by homocysteine

Effect of Fe2+ (Fe3+) Doping on Structural Properties of CeO2 Nanocrystals

We have measured the Raman scattering and magnetization of pure and Fe2+(Fe3+) doped CeO2 nanopowders at room temperature. The Raman scattering spectra revealed the existence of CeO2 fluorite cubic structure for all investigated samples. The Raman active mode at about 600 cm(-1), seen in all samples, can be ascribed to the CeO2 intrinsic oxygen vacancies. Additional Raman modes at 720 cm(-1), 1320 cm(-1) and 1600 cm(-1), which appear in the spectra of doped samples, can be assigned to maghemite (gamma-Fe2O3) cation deficient structure, to 2 omega(LO) IR-allowed overtone and two magnon structure, respectively. This implies that our powders are composed of mixed valence states and have defective structure. Presence of oxygen defect states and magnetic ions can be responsible for the observed ferromagnetism at room temperature in both pure and Fe doped samples.Symposium on Raman Scattering in Materials Science, Sep 15-19, 2008, Warsaw, Polan

Enhanced photocatalytic degradation of RO16 dye using Ag modified ZnO nanopowders prepared by the solvothermal method

In this work, Zn(CH3 COO)(2) 2 H-2 O with AgNO3 content from 0 to 6 mol% was solvothermally treated at 120 C for 18 h in the presence of poly(vinyl pyrrolidone), ethylene glycol and sodium hydroxide. The structural , microstructural and photocatalytic properties of the unmodified and Ag modified ZnO powders have been investigated by the XRPD, FESEM, TEM, UV-vis, Raman and BET techniques. The Ag modified samples consist of ZnO nanocrystals and metallic Ag on the surface. The average crystallite size of all samples was about 20 nm. The FESEM revealed the uniformity in size and approximately spherical shape of ZnO nanopar-ticles. The BET data suggest that all prepared samples are mesoporous. All prepared samples showed higher photocatalytic efficiency in the degradation of the Reactive Orange 16 (RO16) azo dye than the commercial ZnO. In addition, Ag modified ZnO powders, especially those with 1.5 and 0.75 mol% of Ag, were more efficient than the unmodified one

Hydrothermal Synthesis of CeO2 and Ce0.9Fe0.1O2 Nanocrystals

Pure and 10 mol% Fe3+ doped CeO2 nanocrystals were synthesized by hydrothermal method using two different basic solutions (NH4OH and NaOH). All the samples were calcinated at 140 degrees C and 200 degrees C. The characterization of crystalline structure, vibrational and optical properties was performed using X-ray diffraction, Raman spectroscopy and spectroscopic ellipsometry. The obtained results showed that the Fe-doped samples are solid solutions with different size of nanocrystals, very dependent on the synthesis temperature and type of basic solution. The Raman measurements demonstrated electron molecular vibrational coupling and increase of oxygen vacancy concentration whereas doping provokes a small decrease of optical absorption edge in comparison with pure ceria.International School and Conference on Photonics (PHOTONICA09), Aug 24-28, 2009, Belgrade, Serbi

Human genomics of the humoral immune response against polyomaviruses

Publisher Copyright: © The Author(s) 2021. Published by Oxford University Press.Human polyomaviruses are widespread in humans and can cause severe disease in immunocompromised individuals. To identify human genetic determinants of the humoral immune response against polyomaviruses, we performed genome-wide association studies and meta-analyses of qualitative and quantitative immunoglobulin G responses against BK polyomavirus (BKPyV), JC polyomavirus (JCPyV), Merkel cellpolyomavirus (MCPyV), WU polyomavirus (WUPyV), and human polyomavirus 6 (HPyV6) in 15,660 individuals of European ancestry from three independent studies. We observed significant associations for all tested viruses: JCPyV, HPyV6, and MCPyV associated with human leukocyte antigen class II variation, BKPyV and JCPyV with variants in FUT2, responsible for secretor status, MCPyV with variants in STING1, involved in interferon induction, and WUPyV with a functional variant in MUC1, previously associated with risk for gastric cancer. These results provide insights into the genetic control of a family of very prevalent human viruses, highlighting genes and pathways that play a modulating role in human humoral immunity.Peer reviewe

Status Report and Beam Time Request for Experiment AD-4

Summary of current status and plans for October 200

Structural investigation of mechanically activated ZnO powder

Commercially available ZnO powder was mechanically activated in a planetary ball mill. In order to investigate the specific surface area, pore volume and microstructure of non-activated and mechanically activated ZnO powders the authors performed N-2 physisorption, SEM and TEM. Crystallite size and lattice microstrain were analyzed by X-ray diffraction method. XRD patterns indicate that peak intensities are getting lower and expend with activation time. The reduction in crystallite size and increasing of lattice microstrain with prolonged milling time were determined applying the Rietveld's method. The difference between non-activated and the activated powder has been also observed by X-ray photoelectron spectroscopy (XPS). XPS is used for investigating the chemical bonding of ZnO powder by analyzing the energy of photoelectrons. The lattice vibration spectra were obtained using Raman spectroscopy. In Raman spectra some changes along with atypical resonant scattering were noticed, which were caused by mechanical activation

Management of intra-abdominal infections : recommendations by the WSES 2016 consensus conference

This paper reports on the consensus conference on the management of intra-abdominal infections (IAIs) which was held on July 23, 2016, in Dublin, Ireland, as a part of the annual World Society of Emergency Surgery (WSES) meeting. This document covers all aspects of the management of IAIs. The Grading of Recommendations Assessment, Development and Evaluation recommendation is used, and this document represents the executive summary of the consensus conference findings.Peer reviewe