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B Gonsior

Publications and source records attributed to B Gonsior.

16 recordsLinked to original sources
PubMed2000

Comparison of different excitation methods for X-ray spectral analysis: the case of synchrotron radiation.

Different excitation means, protons, photons and electrons (PIXE, XRFA, and EPMA, respectively) have previously been compared with regard to the figures of merit, i.e. detection power, precision and accuracy. The aim in this article is to compare synchrotron radiation SR as another excitation method with the methods mentioned above. From this point of view the evaluation of (SR) was missing as an again independently optimized excitation method and was based as previously on practical problems of trace analysis, in this case on the determinations of traces in lead. The experiment has been performed with thick homogeneous samples of lead, the same samples already used in the former work, so that a direct comparison is possible. The calculation of the figures of merit is based on the measurements of the blank values and their relative standard deviation for the detection limit and on the random errors for the precision. Regarding the thick homogeneous target of lead XRFA still turns out to be the best method, whereas Synchrotron X-Ray Fluorescence SY-XRF compares favorably, at least for larger atomic numbers Z. Even PIXE is inferior to (SY-XRF) in the case of larger Z; when information on the lateral distribution of the elements is of interest, PIXE is indispensable.

Journal Article↗
PubMed1992

Calcification of the aortic wall in hypercalcemic rabbits.

The mineralization process was investigated in the aortic wall of hypercalcemic rabbits. The elevated calcium level in serum was induced by intramuscular injection of vitamin D3. The animals were killed at different times of the experiment (max. 246 d). The freeze-dried tissue homogenates were used for elemental composition studies by means of proton induced X-ray emission (PIXE) and atomic absorption spectroscopy. The structural information was obtained from infrared (IR) and X-ray diffraction (XRD) spectra. Moreover, the ascending part of the aortic arch was separated and used for micro-PIXE (PIXE in combination with proton microprobe) and histochemical examinations. It was found that hypercalcemia (blood serum Ca content elevated by about 20%) induced calcification of the aortic wall. The mineral phase within the aortic wall consisted of Ca-P salts. The Ca/P ratio continuously increased during the experiment and approached 2 after 246 d of the vitamin D3 treatment. The IR and XRD studies made possible the identification of the complex phase composition of the samples. The hydroxyapatite crystals were detected after 196 days, however, in earlier phases of the experiment, amorphous calcium phosphate, dicalcium phosphate dihydrate and octacalcium phosphate were also observed. On the basis of the data obtained, the mechanism of the precipitation and growth of inorganic deposits in the tunica media of the aortic wall was discussed.

Animals↗
PubMed1991

PIXE analysis in uninvolved skin of atopic patients and aged skin.

PIXE (proton-induced X-ray emission) analysis was used to determine the elemental distribution in normal-appearing skin of patients suffering from atopic eczema and in the skin of elderly people. With this technique, elements with atomic numbers greater than or equal to 14 can be detected simultaneously in cryosections of skin biopsies down to a concentration of 1 ppm. Compared with a control group, the epidermal concentrations of Zn and Cu, which are constituent parts of a variety of enzymes, were increased in uninvolved skin of patients with atopic eczema. An increased concentration of these two metals might indicate that even in the epidermis of clinically normal skin of atopic patients, the content of certain enzymes is increased. In the epidermis of elderly people the level of K was lower and that of Ca was higher than in the epidermis of a younger age group. The decreased K level may reflect a reduction of the intracellular volume in the epidermis of aged skin. As high Ca concentrations inhibit the proliferation of and promote the differentiation of keratinocytes, elevated Ca levels may be of importance for the age-associated decrease in epidermal turnover rate.

Adult↗
PubMed1990

Intramembranaceous ossification analyses by a proton microprobe.

The proton induced X-ray emission method in combination with a proton microprobe was applied to study the intramembranaceous ossification. As material sections of mouse embryo skulls from the 17th and 19th day of gestation were used. The morphology of the sample was examined by routine histochemical procedure performed on the sections adjacent to that irradiated by the proton microprobe. The measurements were made in line scan and raster scan mode. The concentrations of P, S, Cl, K, Ca, Fe and Zn were determined at each irradiated point. The average element concentrations were calculated for four parts of each section (bone, cartilage, mesenchymal tissue close to the bone and mesenchymal tissue in other places). The distributions of Ca and P (less markedly than Ca) concentrations almost exclusively correlate with localization of the bone while S, Cl and K concentrations show preference to the cartilage. The amount of inorganic material in flat bones of the 17-day embryo amounts to 14% of the dry mass. The material is characterized by a Ca/P ratio of about 1.6. In the embryo 2 days older the amount of the inorganic phase is practically the same (15%) while the Ca/P ratio approaches 2. This suggests the presence of the precursor phase in the flat bone calcification. It is possible that octacalcium phosphate (Ca/P ratio equals to 1.72) is formed at the onset of the flat bone mineralization which transforms rapidly (in 2 days) to a more stable mineral (defective hydroxyapatite).

Animals↗
PubMed1989

The analysis of mineral deposits and proteoglycans content in the cartilage of mouse trachea using PIXE in combination with proton microprobe.

The tracheal cartilage of mature mice have been investigated using PIXE (proton induced X-ray emission) in combination with a proton microprobe on snap frozen cryosectioned material. The localization and quantitative measurements of P, S, Cl, K, Ca, Fe, and Zn concentrations as well as direct and indirect assessment of glycosaminoglycans by measurement of S content and measurement of bound colloidal iron at pH = 1.8 has been performed. Adjacent sections were stained with the Hale method in Müller modifications and the v. Koss method for sulphated mucins and inorganic deposits respectively. It has been found that hyaline cartilage in trachea contains mineral deposits and that P + Ca amounts up to 22% of cartilage dry mass. The Ca/P ratio approaches 2 what indicates hydroxyapatite type crystals. The cartilage contains substantial amounts of S reflecting the presence of sulphate groups. It was found that the cartilage binds also colloidal iron at low pH. There is a good correlation between places with high amount of bound colloidal iron assessed by PIXE and places showing strong Prussian Blue staining. The Fe/S ratio was, however, much lower in the cartilage than in other tissues what indicates that the colloidal iron method does not give quantitative results. There were no regions showing substantial decrease in Fe/S ratio which we found previously as typical for degenerating and calcifying growth plate cartilage. This may be connected with a relatively low degree of calcification degree of the tracheal cartilage.

Animals↗
PubMed1988

Measurements of mineralization process in the femur growth plate and rib cartilage of the mouse using pixe in combination with a proton microprobe.

The femoral bone from the 18-day pregnancy embryo and an rib cartilage of mature mice have been investigated using PIXE (proton induced X-ray emission) in combination with a proton microprobe on snap frozen cryosectioned material. The localization and the results of quantitative measurement of P, S, Cl, K, Ca, Fe and Zn have been correlated with the histochemical localization of inorganic deposits. It has been found that in calcifying and degenerating cartilage of the growth plate there is substantial loss of S; this element being indicative for sulphate groups of glycosaminoglycans. This change seems to be an important factor conditioning the process of mineralization. Zn is found in higher concentration in mineralized tissues, both in embryonal and mature cartilage as well as in the bone, and this suggests that Zn is also involved in the mineralization process. The mineralization of rib cartilage exceeds that of embryonal bone, and the Ca/P ratio is higher in the former than in the hydroxyapatite of the latter. The method described is a useful analytical tool especially for such types of studies in which elements are not easily redistributed by freezing, cutting and drying; e.g. in investigations of mineral deposits.

Animals↗
PubMed1988

Measurement of colloidal iron binding at low pH in cartilage using the proton microprobe.

Quantitative micro-PIXE analysis was performed on mouse embryo epiphyseal cartilage and on the rib cartilage of mature animals after incubation of sections with colloidal iron at pH 1.8. The iron content as well as that of sulphur and phosphorus and Fe/S, Fe/P ratios were determined. It was found that colloidal iron content was higher in the cartilage than in other tissues. The cartilage also displayed the highest content of sulphur. The Fe/S ratio was however not constant, being highest in the degeneration zone close to the mineralization front, where the binding of iron was strongest while the amount of sulphur decreased. This indicates that factors other than number of sulphate groups influence the binding of positively charged molecules to glycosaminoglycans. This is confirmed by differences in the results obtained for embryonic and mature rib cartilage.

Aging↗
PubMed1987

PIXE analysis in different stages of psoriatic skin.

Elemental distribution in psoriatic skin varies with the functional state of the keratinocytes, e.g., electrolytes influence cell metabolism and cell proliferation, and trace elements play a crucial role in a great number of enzymes. Elemental distribution in pinpoint lesions, old plaques, and uninvolved skin of 5 psoriatic patients and 4 healthy controls was studied by means of PIXE (proton-induced x-ray emission) analysis. This technique allows the simultaneous detection of elements with an atomic number greater than or equal to 14 along the epidermis and dermis in freeze-dried skin biopsies. Trace elements such as Fe, Cu, and Zn were determined down to a level of 1 ppm. In comparison with uninvolved skin, concentrations of P and K were elevated in psoriatic epidermis. In addition, increased levels of K were correlated with the stage of the psoriatic lesion. Zinc concentrations were significantly elevated in pinpoint lesions. The Zn concentration profiles within the epidermis and upper dermis showed high correlation to the P concentration profiles. Iron levels were decreased in old psoriatic plaques, whereas Cu concentrations varied considerably. In comparison to the controls, Cl concentrations were markedly decreased in the dermis of involved and uninvolved psoriatic skin, whereas epidermal Cl levels were unaffected. As high K levels prevent the Ca-induced differentiation of keratinocytes, high K levels may be the cause of the high cell differentiation in psoriatic skin. Elevated DNA- and RNA-polymerases might be the cause of elevated Zn levels in pinpoint lesions.

Adult↗