Micro-PIXE with 3.5 MeV protons for the study of low copper concentrations in atherosclerotic artery

The onset and progression of many degenerative diseases including atherosclerosis, have been shown to directly link to the presence/absence of certain metal ions. Consequently, the detection of these ions in tissues may improve the understanding of the driving pathophysiology. The Cu content during atherosclerosis development has not been studied due to its low concentration involved. In this work, the Cu level in atherosclerotic rabbit tissue is determined using PIXE with a 3.5 MeV proton beam. The arteries of three animal groups fed with different diets were studied: group 1, rabbits on normal standard diet, group 2, on High Fat Diet (HFD) and group 3, on HFD + Zinc diet. Zinc supplement has been proven to inhibit the beginning of atherosclerotic lesion. The result of this study shows that the Cu levels in all the atherosclerotic lesions were lower than that in the arterial walls of the samples in HFD groupThis work has been partially funded by a UAM-Banco de Santander Interuniversity Cooperation with Asia Grant (2017–2018) and by the Ministerio de Ciencia, Innovacióny Universidades (CTQ2017-84309-C2-2-R

Zinc deficiency decreased cell viability both in endothelial EA.hy926 cells and mouse aortic culture ex vivo and its implication for anti-atherosclerosis

Zinc plays a protective role in anti-atherosclerosis but the clear mechanism has not been proposed yet. In the present study, we evaluated whether zinc modulates atherosclerotic markers, VACM-1 and ICAM-1 and cell viability both in endothelial cells in vitro and mouse aortic cell viability ex vivo. In study 1, as in vitro model, endothelial EA.hy926 cells were treated with TNFα for 5 hours for inducing oxidative stress, and then treated with Zn-adequacy (15 µM Zn) or Zn-deficiency (0 µM Zn) for 6 hours. Pro-atherosclerosis factors, VCAM-1 and ICAM-1 mRNA expression and cell viability was measured. In study 2, as ex vivo model, mouse aorta ring was used. Mourse aorta was removed and cut in ring then, cultured in a 96-well plate. Aortic ring was treated with various TNFα (0-30 mg/ml) and intracellular zinc chelator, N, N, N', N', -tetrakis (2-pyridylmethyl) ethylenediamine (TPEN, 0-30 µM) for cellular zinc depletion for 2 days and then cell viability was measured. The results showed that in in vitro study, Zn-adequate group induced more VCAM-1 & ICAM-1 mRNA expression than Zn-deficient group during 6-hour zinc treatment post-5 hour TNF-α treatment, unexpectedly. These results might be cautiously interpreted that zinc would biologically induce the early expression of anti-oxidative stress through the increased adhesion molecule expression for reducing atherosclerotic action, particularly under the present 6-hour zinc treatment. In ex vivo, mouse aortic ring cell viability was decreased as TNF-α and TPEN levels increased, which suggests that mouse aortic blood vessel cell viability was decreased, when oxidative stress increases and cellular zinc level decreases. Taken together, it can be suggested that zinc may have a protective role in anti-atherosclerosis by cell viability in endothelial cells and aorta tissue. Further study is needed to clarify how pro-atherosclerosis molecule expression is modulated by zinc

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

NUCLEAR MICROSCOPY APPLICATIONS IN BIOMEDICAL RESEARCH

Master'sMASTER OF SCIENC

Tetrahedrite (Cu12Sb4S13) thin films for photovoltaic and thermoelectric applications

In this paper we have demonstrated the growth of Cu12Sb4S13 thin film through e-beam evaporation from a single source. The source material was pre-synthesised via ball mill method starting from a stoichiometric mixture of elements (Cu, Sb and S) taken in the atomic ratio of 12:4:13. The films were deposited at different beam currents viz. 40, 50 and 60 mA. The bulk material and thin films were studied using X-ray diffraction (XRD) and Raman spectroscopy to evaluate phase formation. The films grown at beam current values of 40 mA showed the presence of Cu12Sb4S13 phase along with Cu3SbS4 and CuS secondary phases. The films grown at 50 mA and 60 mA are showing Cu3SbS4 phase as main phase. These results are in agreement with the Raman studies. The composition of as grown films was analysed using Rutherford backscattered spectrometry (RBS) and proton induced X-ray emission (PIXE) measurements. The Cu content in the films is decreasing with increase in the beam current, whereas the Sb and S content shows increment. The optical absorption measurement was used to determine the optical band gap. The films show a direct band gap value of similar to 1.8 eV with an optical absorption coefficient of similar to 10(5) cm(-1). Temperature dependant Seebeck coefficient and electrical resistivity values were measured for the thin films and the power factor values were calculated. The positive Seebeck coefficient values obtained indicate p-type semiconducting nature of the films. The maximum power factor of 2.30 mu W/cm-K-2 at 495 K was obtained for films grown at 40 mA e-beam current. The electrical and optical properties are significantly influenced by the presence of secondary phases and compositional deviation

Distribution of selected elements in atherosclerotic plaques of apoE/LDLR-double knockout mice subjected to dietary and pharmacological treatments

10.1016/j.radphyschem.2011.02.021Radiation Physics and Chemistry80101072-1077RPCH

Does iron inhibit calcification during atherosclerosis?

10.1016/j.freeradbiomed.2012.07.014Free Radical Biology and Medicine5391675-1679FRBM