35 research outputs found
Mercury chloride-induced oxidative stress in human erythrocytes and the effect of vitamins C and E in vitro
Mercury can exist in the environment as metal, as monovalent and divalent salts and as organomercurials, one of the most important of which is mercuric chloride (HgCl2). It has been shown to induce oxidative stress in erythrocytes through the generation of free radicals and alteration of thecellular antioxidant defense system. The effect of simultaneous pretreatment with vitamins C and E on the toxicity of HgCl2 in human erythrocytes was evaluated. We examined the effect of several differentdoses of HgCl2 (1.052, 5.262, 10.524 M), or HgCl2 in combination with vitamin C (VC; 10 M) and vitamin E (VE; 30 M), on the levels of malondialdehyde (MDA) and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities in human erythrocytes in vitro. Erythrocytes were incubated under various treatment conditions (HgCl2 alone, vitamins alone, or HgCl2 plus vitamin) at 37°C for 60 min and the levels of MDA and SOD, CAT and GPx activities, were determined. Treatment with HgCl2 alone increased the levels of MDA and decreased SOD, CAT and GPx activities in erythrocytes (P < 0.05). VC and VE-pretreated erythrocytes showed a significant protection aganist thecytotoxic effects induced by HgCl2 on the studied parameters. There were no statistical differences among VC+VE-treated erythrocytes, as compared to non-treated control cells. These results indicated that the presence of vitamins at concentrations that are similar to the levels found in plasma could be able to ameliorate HgCl2-induced oxidative stress by decreasing lipid peroxidation and altering antioxidant defense system in erythrocytes
Precise mapping of the magnetic field in the CMS barrel yoke using cosmic rays
This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 IOPThe CMS detector is designed around a large 4 T superconducting solenoid, enclosed in a 12 000-tonne steel return yoke. A detailed map of the magnetic field is required for the accurate simulation and reconstruction of physics events in the CMS detector, not only in the inner tracking region inside the solenoid but also in the large and complex structure of the steel yoke, which is instrumented with muon chambers. Using a large sample of cosmic muon events collected by CMS in 2008, the field in the steel of the barrel yoke has been determined with a precision of 3 to 8% depending on the location.This work is supported by FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ,
and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS
(Colombia); MSES (Croatia); RPF (Cyprus); Academy of Sciences and NICPB (Estonia);
Academy of Finland, ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR
(Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE (Russia); MSTDS (Serbia); MICINN and CPAN (Spain); Swiss Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey); STFC (United Kingdom); DOE and NSF (USA)