Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 8

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Possible Causes of Asymmetry in the Mössbauer Spectra of~Brain Tissue

100%
Szlachta K., Gałązka-Friedman J.
Acta Physica Polonica A
|
2011
|
vol. 119
|
issue 1
84-87
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.
2
Content available remote

T1 and T2 Relaxation Times from Substantia Nigra in Parkinson's Disease and Control

81%
Kuliński R., Szlachta K., Gałązka-Friedman J., Friedman A.
|
|
vol. 125
|
issue 4
869-871
EN
The diagnosis of Parkinson's disease, and also other neurodegenerative disorders, is based on clinical examination. Many attempts are undertaken to find a test that could confirm this clinical diagnosis. Many hopes were attributed to magnetic resonance imaging but its importance remains obscure. The aim of this study was to compare T1 and T2 relaxation times from substantia nigra of patients with clinical diagnosis of Parkinson's disease and age-matched controls. A decrease of T2 (54.5 ± 1.4 ms vs. 58.0 ± 1.5 ms) in Parkinson's disease vs. control was found with confidence level of 5%. T1 did not differ significantly between Parkinson's disease and control (624 ± 17 ms vs. 614 ± 21 ms).
3
Content available remote

The Catalogue of Martian Mössbauer Spectra

81%
Maliszewski A., Gałązka-Friedman J., Szlachta K., Urbanski M.
Acta Physica Polonica A
|
2011
|
vol. 119
|
issue 1
10-11
EN
The suggestion of sending a Mössbauer spectrometer to the surface of Mars was elaborated in 1988 year. In 1989 realization of this project was taken by scientists from Western Europe and USSR. Finally a Mössbauer spectrometer adapted to measurements on the surface of Mars was constructed by an international team under the guidance of G. Klingelhöfer. Mössbauer data from Mars are available for open public access on a web site of Planetary Data System. Based on these data the catalogue of Martian Mössbauer spectra was prepared and located on the web site of one of the author (JGF). The aim of the construction of this catalogue was to create the possibility to compare quickly spectra from different places on the Martian surface.
4
Content available remote

Different Signals of Magnetic Resonance Imaging and Ultrasound from Substantia Nigra in Parkinson's Disease and Control - Is Iron the Cause?

71%
Szlachta K., Sadowski K., Kuliński R., Gałązka-Friedman J., Friedman A.
Acta Physica Polonica A
|
2012
|
vol. 121
|
issue 2
454-456
EN
Motor symptoms of Parkinson's disease are caused by a progressive degeneration of substantia nigra, a small structure located deep in the brain. The cause of this process is unknown but may be related to iron mediated oxidative stress. The aim of this study was to understand the mechanism of the change of magnetic resonance and ultrasound signals found in patients with Parkinson's disease, which were attributed by several authors to an important increase of the concentration of iron in substantia nigra. USG and MRI measurements were performed on phantoms simulating human brain to which high amounts of iron were introduced. The USG signal was unaffected by insertion of iron-loaded ferritin, while it was by insertion of glial tissue. Injections of iron-loaded ferritin and iron ions to the phantoms decreased T_2 relaxation time. Our results suggest that the observed change of the signal from Parkinsonian brains is probably due to a proliferation of glia and not to an increase of the concentration of iron.
5
Content available remote

Mössbauer Studies of Volhynian Basalts

71%
Bakun-Czubarow N., Milczarski J., Gałązka-Friedman J., Szlachta K., Forder S.
Acta Physica Polonica A
|
2011
|
vol. 119
|
issue 1
7-9
EN
The Volhynian basalts studied belong to the effusive-tuffogenic Volhynian Series (Sławatycze Series in Poland), being the large Ediacaran continental igneous province, that covers an area of 200 000 km^{2} in the western margin of East European Craton. The series is underlain by the Cryogenian terrigenous Polesie Series with doleritic sills and dikes. The Volhynian Series consists of the rock beds belonging to the three volcanic cycles with different ratios of flood basalts to pyroclastics. The aim of the study was recognition of primary and secondary Fe-bearing minerals, particularly Fe- and Fe-Ti oxides as well as determination of iron oxidation state, that is an important tool in the search for native copper deposits in these rocks. For Mössbauer studies the following rock samples were chosen: the Polesie Series dolerites, the Volhynian Series basalts from the Ukrainian quarries and drill-holes, e.g. from the Volodymir Volhynskaya drilling hole; the Sławatycze Series basalts from Kaplonosy drill-hole in Poland. In the Kaplonosy basalts the content of magnetite decreases with depth, which may be caused by magma differentiation due to fractional crystallization, when Mg content decreases as Ti and Fe - increases in basic magma. In the Kaplonosy basalts the Fe^{2+}/Fe^{3+} ratio increases with depth, which points to the increase of iron oxidation with the progress of basaltic magma differentiation.
6
Content available remote

Comparison of Magnetic and Mössbauer Results Obtained for Palaeozoic Rocks of Hornsund, Southern Spitsbergen, Arctic

71%
Szlachta K., Michalski K., Brzózka K., Górka B., Gałązka-Friedman J.
Acta Physica Polonica A
|
2008
|
vol. 114
|
issue 6
1675-1682
EN
This analysis was performed as a part of the palaeomagnetic project focused on the reconstruction of the palaeogeographic position of the Svalbard Archipelago and adjacent crustal units (European Arctic) in the Palaeozoic and Mesozoic. Three rock formations - Cambrian, Devonian and Carboniferous were sampled in the area of Hornsund, southern Spitsbergen. The main aim of the presented study is to identify ferromagnetic minerals (sensu lato) - the carriers of the natural remanent magnetisation in the investigated rocks. A wide range of magnetic methods were used: the Lowrie tests, unblocking temperatures determinations and the measurement of coercivity spectra as well as the Mössbauer studies. In Devonian and Carboniferous samples all applied methods indicate the domination of the hematite natural remanent magnetisation carrier. In Cambrian rocks magnetic measurements reveal a mixture of ferromagnetic (sensu lato) minerals with varying coercivities and unblocking temperatures. The Mössbauer data improve the identification, suggesting that in Cambrian rocks the carrier of the dominating natural remanent magnetisation component is maghemite.
7
Content available remote

Mössbauer Studies of Pathological Brain Tissues Affected by PSP Disease

61%
Gałązka-Friedman J., Bauminger E., Szlachta K., Schweitzer K., Wszolek Z., Dickson D., Friedman A.
Acta Physica Polonica A
|
2009
|
vol. 115
|
issue 2
545-547
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.
8
Content available remote

Iron in Alzheimer's and Control Hippocampi - Mössbauer, Atomic Absorption and ELISA Studies

52%
Gałązka-Friedman J., Bauminger E., Szlachta K., Koziorowski D., Tomasiuk R., Jaklewicz A., Wszołek Z., Dickson D., Kaplińska K., Friedman A.
Acta Physica Polonica A
|
2011
|
vol. 119
|
issue 1
81-83
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.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.