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EN
Progressive supranuclear palsy (PSP) is a neurological disease leading to the damage of two brain structures: globus pallidus and substantia nigra. The pathomechanism of this disease is still unknown. One of the hypotheses is oxidative stress. Oxidative stress is an overproduction of free radicals in which iron may be involved. To verify the hypothesis that iron may play a role in PSP we performed the Mössbauer comparative studies of pathological and control tissues. Ten samples of PSP globus pallidus, ten samples of PSP substantia nigra, twelve control samples of globus pallidus and nine control samples of substantia nigra were measured in a conventional Mössbauer spectrometer at 90 K. The Mössbauer spectra obtained for all samples showed well resolved doublets with an isomer shift of 0.46±0.01 mm/s and a quadruple splitting of 0.70±0.02 mm/s. The main difference in these preliminary studies was in the concentration of iron. The concentration in PSP samples in globus pallidus was found to be 257±19 ng/mg tissue, compared to 183±22 ng/mg in control samples and 301±26 ng/mg in substantia nigra compared to 188±22 ng/mg in control samples. Taking into consideration that we did not notice any substantial increase in iron concentration in Parkinsonian substantia nigra compared to control substantia nigra, but a substantial increase in both substantia nigra and globus pallidus in PSP, may suggest that iron plays a different role in the pathomechanisms of PSP and of Parkinson's disease.
EN
Determination of the iron state (Fe²⁺ or Fe³⁺) and content of iron in commercial pharmaceutical products containing ferrous fumarate FeC₄H₂O₄ was made by the Mössbauer spectroscopy and X-ray fluorescence method. Also, influence of thermal treatment on stability of ferrous fumarate in selected medicaments has been investigated. The investigated samples were annealed in definite temperature: 373, 473, and 573 K for 5 h. Room temperature Mössbauer spectra of initial samples gave clear evidence that two phases of iron were presented. The major component was connected with ferrous fumarate with a contribution from ≈85% to ≈50%, depending on investigated medicaments. Ferrous fumarate was stable up to annealing temperature 473 K. Above this temperature significant oxidation of Fe²⁺ to Fe³⁺ was observed.
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EN
Mössbauer (nuclear gamma-resonance) spectroscopy was used to study various industrial samples of vitamins and dietary supplements containing iron ions, which are used in the anemia treatment. Determination of the iron state (Fe²⁺ or Fe³⁺) in medicaments is important for the pharmaceuticals evaluation quality. The investigated samples contain ferrous fumarate, ferrous gluconiate and ferric diphosphate. ⁵⁷Fe hyperfine parameters of the studied pharmaceuticals indicate that there exist major iron ferrous and ferric compounds. However, Mossbauer spectra of the investigated samples demonstrated the presence of additional ferrous and ferric components, probably related to impurities or to a partially modified main component.
EN
Iron present in the human brain plays important role in neurodegenerative diseases like Parkinson and Alzheimer diseases. Brain iron is mainly stored within globular protein called ferritin. Mössbauer spectra of brain tissue are asymmetric doublets at 300 K and 90 K. This asymmetry is slightly bigger in the case of samples taken from diseased subjects. Reason for this is still unknown. Few possible causes of aforesaid difference had been discussed. Nanometer-size of ferritin iron cores, pathological protein influence were taken into account. It was also discussed if experimentally available statistics is sufficient to obtain reliable asymmetry coefficient from Mössbauer spectra. Physical experiment were reproduced by means of computer simulations. Nevertheless, the reason for the asymmetry has not been completely elucidated yet.
EN
Alzheimer disease is a neurodegenerative process of unknown mechanism taking place in a part of the brain - hippocampus. Oxidative stress and the role of iron in it is one of the suggested mechanisms of cells death. In this study several methods were used to assess iron and iron binding compounds in human hippocampus tissues. Mössbauer spectroscopy was used for identification of the iron binding compound and determination of total iron concentration in 12 control and one Alzheimer disease sample of hippocampus. Mössbauer parameters obtained for all samples suggest that most of the iron is ferritin-like iron. The average concentration of iron determined by Mössbauer spectroscopy in control hippocampus was 45±10 ng/mg wet tissue. The average concentration of iron in 10 Alzheimer disease samples determined by atomic absorption was 66±13 ng/mg wet tissue. The concentration of H and L chains of ferritin in 20 control and 10 AD hippocampi was assessed with enzyme-linked immuno-absorbent assay. The concentration of H and L ferritin was higher in Alzheimer disease compared to control (19.36±1.51 vs. 5.84±0.55 ng/μg protein for H, and 1.39±0.25 vs. 0.55±0.10 for L). This 3-fold increase of the concentration of ferritin is accompanied by a small increase of the total iron concentration.
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The 100 nm particles of Fe_{2}O_{3} and metallic Fe sedimented jointly with Al_{2}O_{3} powder from their suspension in oleic acid exhibit distinguished mobility which depends on the concentration of aluminum oxide. This observation is interpreted as the result of the interparticle Fe-Fe magnetic interactions which lead to the formation of the rigid network of magnetic metallic iron nanoparticles.
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Mössbauer Spectrometry Study of Biological Tissues

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EN
Magnetic microstructure of iron contained in selected biological tissues is characterized and mutually compared. We have studied three types of biological samples prepared from human brain, human and horse spleen. Original samples were lyophilized (dried in a vacuum) thus providing powder forms. As a principal method of study, ⁵⁷Fe Mössbauer spectrometry in transmission mode was used. The Mössbauer spectrometry experiments were performed at room ( ≈300 K) and at liquid helium (4.2 K) temperature. At room temperature Mössbauer spectra show doublet-like features. Such behaviour indicates possible presence of nanoparticles with fluctuating magnetic moments that acquire arbitrary positions. On the other hand, low temperature Mössbauer spectrometry measurements demonstrate significant contribution of sextets that confirmed occurrence of blocked magnetic moments of iron-containing particles. Different relative contributions of magnetic components in the low temperature spectra for the three inspected biological tissues suggest differences in the blocking temperatures of the magnetic nanoparticles present in them.
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