Glioblastoma multiforme influence on the elemental homeostasis of the distant organs: the results of inter-comparison study carried out with TXRF method.

Glioblastoma (GBM) is a fast-growing and aggressive brain tumor which invades the nearby brain tissue but generally does not spread to the distant organs. Nonetheless, if untreated, GBM can result in patient death in time even less than few months from the diagnosis. The influence of the tumor progress on organs other than brain is obvious but still not well described. Therefore, we examined the elemental abnormalities appearing in selected body organs (kidney, heart, spleen, lung) in two rat models of GBM. The animals used for the study were subjected to the implantation of human GBM cell lines (U87MG and T98G) characterized by different levels of invasiveness. The elemental analysis of digested organ samples was carried out using the total reflection X-ray fluorescence (TXRF) method, independently, in three European laboratories utilizing various commercially available TXRF spectrometers. The comparison of the data obtained for animals subjected to T98G and U87MG cells implantation showed a number of elemental anomalies in the examined organs. What is more, the abnormalities were found for rats even if neoplastic tumor did not develop in their brains. The most of alterations for both experimental groups were noted in the spleen and lungs, with the direction of the found element changes in these organs being the opposite. The observed disorders of element homeostasis may result from many processes occurring in the animal body as a result of implantation of cancer cells or the development of GBM, including inflammation, anemia of chronic disease or changes in iron metabolism. Tumor induced changes in organ elemental composition detected in cooperating laboratories were usually in a good agreement. In case of elements with higher atomic numbers (Fe, Cu, Zn and Se), 88% of the results were classified as fully compliant. Some discrepancies between the laboratories were found for lighter elements (P, S, K and Ca). However, also in this case, the obtained results fulfilled the requirements of full (the results from three laboratories were in agreement) or partial agreement (the results from two laboratories were in agreement).

The right coronary artery in the heart of chinchilla (Chinchilla laniger Molina).

The pattern of normal coronary vascularization in a mammalian heart includes the presence of both right and left coronary arteries. According to the literature data, the presence of single major coronary arteries is mainly related to cardiac abnormalities. Previously it has been reported that the right coronary artery is absent in the coronary vascularization of the heart in the chinchilla. Our research was carried out on thirty chinchillas (Chinchilla laniger Molina). The coronary vessels were filled with colored latex to render them visible. The examinations were supplemented additionally with the use of microcomputed tomography with arterial contrast. Our study demonstrates its undoubtedly presence of the right coronary artery. In all subjects the right coronary artery was present, as was the left coronary artery. Two types of right coronary artery were found. Our results indicate that the normal pattern of coronary vascularization of heart in chinchilla includes both the right and left coronary arteries. An open question remains the presence of single coronary artery is a normal pattern of cardiac arterial vascularization in chinchilla.

Studies of Element Concentration in the Lymphocytes, Erythrocytes, and Plasma of Healthy Human Donors Using Total Reflection X-ray Fluorescence.

In this article, the total reflection X-ray fluorescence (TXRF) analysis was used for determination of element concentrations in three isolated peripheral blood components: lymphocytes, erythrocytes, and plasma, collected from 36 healthy donors (15 men and 21 women) from eastern Poland. The studied blood components were isolated from whole peripheral blood using Histopaque-1077 density gradient centrifugation. In the lymphocytes, the following elements were measured: P, S, Cl, K, Ca, Fe, Zn, Br, Sr, and Pb. In the erythrocytes: P, S, Cl, K, Cr, Mn, Fe, Cu, Zn, Se, Br, Rb, and Pb, while in the plasma samples: P, S, Cl, K, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Br, Se, Sr, and Pb. The descriptive statistics parameters of concentration such as: mean value, standard deviation, median, first and third quartiles, 10th and 90th percentiles were calculated for all samples of the studied blood components, as well as separately for male and female groups. The measured element concentrations and calculated parameters can be used as the reference values. Element concentration distributions for male and female groups were statistically compared using the non-parametric Mann-Whitney test and statistical significance differences (α = 0.05) were found for: P (in lymphocytes), Se and Rb (in erythrocytes), and V (in plasma). The multigroup statistical comparison of element concentration distribution for different blood components was also done (Mann-Whitney and Kruskal-Wallis tests). The statistical tests show that the concentration levels are usually different, except in the following cases: Zn, Fe (lymphocytes and plasma, Fe only for female group), Cr (erythrocytes and plasma). The obtained concentration ranges were compared with literature-based data available for element concentration in lymphocytes, erythrocytes, and plasma. In this work, the application of the TXRF method allowed additionally for the simultaneous determination of the concentrations of such elements as: P, S, Cl, Br, Sr and Pb in lymphocytes, S, Cl and Br in erythrocytes, and P, S, Cl, K, Ti, Br and Pb in plasma. From an analytical point of view, the article describes in detail the measurement procedure including the isolation of blood components and samples preparation for TXRF measurements, and later the detection limit of the method is discussed.

Determination of Crystal-Field Splitting Induced by Thermal Oxidation of Titanium.

The electronic structure of transition-metal oxides is a key component responsible for material's optical and chemical properties. Specifically for metal-oxide structures, the crystal-field interaction determines the shape, strength, and occupancy of electronic orbitals. Consequently, the crystal-field splitting and resulting unoccupied state populations can be foreseen as modeling factors of the photochemical activity. Herein, we study the formation of crystal-field effects during thermal oxidation of titanium in an ambient atmosphere and range of temperatures. The X-ray absorption spectroscopy is employed for quantitative analysis of average t2g-eg crystal-field splitting (Δoct) and relative t2g/eg bands occupancy. The obtained result shows that Δoct changes as a function of temperature from 1.97 eV for a passive oxide layer created on a Ti metal surface at room temperature to 2.41 eV at 600 °C when the material changes into the TiO2 rutile phase. On the basis of XAS data analysis, we show that the Δoct values determined from L2 and L3 absorption edges are equal, indicating that the 2p1/2 and 2p3/2 core holes screen the t2g and eg electronic states in a similar manner.

Study of chromium, selenium and bromine concentrations in blood serum of patients with parenteral nutrition treatment using total reflection X-ray fluorescence analysis.

Total reflection X-ray fluorescence analysis (TXRF) was used to determine chromium, selenium and bromine concentrations in blood serum samples of 50 patients with parenteral nutrition treatment. The concentrations were measured two times, namely in the first day (I measurement) of the treatment and the seventh day (II measurement) after the chromium and selenium supplementation. For comparison purposes also serum samples of 50 patients without nutritional disorders, admitted to a planned surgical procedure to remove the gall bladder (cholecystectomy), were analyzed and treated as the control group. Descriptive statistics of measured concentrations of Cr, Se and Br both for the studied and control groups was determined. In order to check the effectiveness of Cr and Se supplementation, the results of the first and seventh day measurements for studied group were statistically compared with each other, with literature reference values and with the results of the control group (two-group comparison). These comparisons indicate the effectiveness of selenium supplementation in the applied treatment procedure. In the case of Cr and Br concentrations no statistically significant differences were observed. We conclude that monitoring of the concentration of the important trace elements in human serum should be standard procedure in parenteral nutrition treatment. In this monitoring the TXRF technique can be successfully used.

Surface Properties of Halloysite-Carbon Nanocomposites and Their Application for Adsorption of Paracetamol.

Analysis of surface properties of halloysite-carbon nanocomposites and non-modified halloysite was carried out with surface sensitive X-ray photoelectron spectroscopy (XPS) and inverse gas chromatography (IGC). The XPS spectra were measured in a wide range of the electron binding energy (survey spectra) and in the region of C 1s photoelectron peak (narrow scans). The IGC results show the changes of halloysite surface from basic for pure halloysite to acidic for carbon-halloysite nanocomposites. Halloysite-carbon nanocomposites were used as adsorbents of paracetamol from an aqueous solution. The adsorption mechanism was found to follow the pseudo-second-order and intra-particle diffusion models. The Langmuir multi-center adsorption model described well the obtained experimental data. The presence of carbon increased significantly the adsorption ability of halloysite-carbon nanocomposites for paracetamol in comparison to the non-modified halloysite.

In situ observation of charge transfer and crystal field formation via high energy resolution X-ray spectroscopy during temperature programmed oxidation.

Herein, it has been demonstrated how resonant X-ray emission spectroscopy can be employed to study the charge transfer dynamics in real-time during the temperature-induced oxidation of metallic tungsten. Application of high energy resolution schemes allowed distinguishing charge transfer to separate orbitals resulting from crystal field splitting. Based on the time-resolved studies, it was possible to determine the corresponding charge transfer rates. From the experimental data, we determined that the electron transfer during the thermal oxidation of the metal dominates in the temperature range of 470-570 °C, reaching a maximum of 0.036 electrons per °C.

The correlation of crystalline and elemental composition of urinary stones with a history of bacterial infections: TXRF, XRPD and PCR-DGGE studies.

The aim of this study was to analyze the correlation between past bacterial infections and the type and chemical composition of urinary stones experienced by human patients. Bacteria have been recognized to contribute to urinary stones; however, the role of uropathogens in the development of specific stones has not been extensively investigated. The detection of past bacterial infection (eleven different bacterial species) in urinary stones from 83 patients was made on a DNA level using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) and correlated with the chemical composition of urinary stones measured using X-ray powder diffraction (XPRD) technique and their elemental composition by total reflection X-ray fluorescence (TXRF). In this study, two scenarios of urinary stones formation mediated by Proteus sp. or Escherichia coli are presented. The first one is associated with Proteus spp. which dominated in 84% of infectious urinary stones and is strongly correlated with struvite and calcium phosphate, in whose matrix additionally strontium, phosphorus, potassium, nickel and zinc are detected. The formation of these stones is closely correlated with urease activity. The second scenario for urinary stone mineralization is associated with E. coli identified in weddellite stones, in which matrix iron was detected. In conclusion, the statistical correlations of bacterial infections with crystalline and elemental composition showed that in mixed bacterial infections, one scenario dominated and excluded the second one.

Biological effects of mixed-ion beams. Part 2: The relative biological effectiveness of CHO-K1 cells irradiated by mixed- and single-ion beams.

The relative biological effectiveness (RBE) values were determined for single- and mixed-ion beams containing carbon and oxygen ions. The CHO-K1 cells were irradiated with beams with the linear energy transfer (LET) values of 236-300 and 461-470 keV/µm for 12C and 16O ions, respectively. The RBE was estimated as a function of dose, survival fraction (SF) and LET. The SF was not affected by varying contributions of the constituent ions to the total mixed dose. The RBE has the same value for single-ion exposures with ions with LET 300 (12C) and 470 keV/µm (16O).

Biological effects of mixed-ion beams. Part 1: Effect of irradiation of the CHO-K1 cells with a mixed-ion beam containing the carbon and oxygen ions.

Carbon and oxygen ions were accelerated simultaneously to estimate the effect of irradiation of living cells with the two different ions. This mixed ion beam was used to irradiate the CHO-K1 cells, and a survival test was performed. The type of the effect of the mixed ion beam on the cells was determined with the isobologram method, whereby survival curves for irradiations with individual ion beams were also used. An additive effect of irradiation with the two ions was found.

Analysis of copper concentration in human serum by application of total reflection X-ray fluorescence method.

The chemotherapy and photon radiotherapy are the most often applied methods in treatment of the cancer diseases because of their effectiveness and high cure rates. Apart from eligible destruction of the tumour, one of the side effects of these treatment methods is possible modification of main and trace element concentration in different human tissues and fluids. In this paper, the copper (Cu) level in human serum was determined by total reflection X-ray fluorescence method in 142 chemotherapy patients and in 44 healthy persons being a control group. The Cu concentration in the chemotherapy group was found to be on the level 1.78 ± 0.909 mg/L, while in the control group, it was 1.08 ± 0.551 mg/L. Performed measurements allowed for calculation of the parameters of copper concentration distribution (mean value, standard deviation, median) for both analysed groups. The theoretical nature of the concentration distribution was tested and found as a log-normal distribution (control group) and a log-stable distribution (chemotherapy group). The copper concentration distributions for both studied group were statistically compared using Kolmogorov-Smirnov test, and the conclusion was that the distributions are statistically different. Serum Cu levels were significantly higher in the chemotherapy group than in the control group. Taking into account the results for the control group, the copper concentration reference quantile ranges in human serum were obtained. The values of the mean, median and other quantiles determined in this case can be applied in two-group comparison studies. The obtained results can be used as a diagnostic tool for chemotherapy patients.

Investigation of the bystander effect in CHO-K1 cells.

AIM: Investigation of the bystander effect in Chinese Hamster Ovary cells (CHO-K1) co-cultured with cells irradiated in the dose range of 0.1-4 Gy of high LET 12C ions and X-rays. BACKGROUND: The radiobiological effects of charged heavy particles on a cellular or molecular level are of fundamental importance in the field of biomedical applications, especially in hadron therapy and space radiation biology. MATERIALS AND METHODS: A heavy ion 12C beam from the Heavy Ion Laboratory of the University of Warsaw (HIL) was used to irradiate CHO-K1 cells. Cells were seeded in Petri dishes specially designed for irradiation purposes. Immediately after irradiation, cells were transferred into transwell culture insert dishes to enable co-culture of irradiated and non-irradiated cells. Cells from the membrane and well shared the medium but could not touch each other. To study bystander effects, a clonogenic survival assay was performed. RESULTS: The survival fraction of cells co-cultured with cells irradiated with 12C ions and X-rays was not reduced. CONCLUSIONS: The bystander effect was not observed in these studies.

Biological effectiveness of (12)C and (20)Ne ions with very high LET.

PURPOSE: To determine the relationship between the relative biological effectiveness (RBE) for cell inactivation and linear energy transfer (LET) in the Bragg peak region of (12)C and (20)Ne ions. MATERIALS AND METHODS: Chinese hamster ovary (CHO-K1) cells were exposed to high LET (12)C (33.2 MeV, 20.3 MeV, 9.1 MeV at cell entrance) and (20)Ne ions (56.2 MeV, 34.7 MeV, 15 MeV at cell entrance) and to low LET x-rays. Technical details of the irradiation facility are presented which is based on the Monte Carlo simulation of the lateral spread of heavy ions as a result of the multiscattering small-angle process in physical conditions of the experimental set-up. RESULTS: RBE has been measured for LET values close to the Bragg peak maximum, i.e., 440-830 keV/microm for (12)C and for 1020-1600 keV/microm for (20)Ne ions. RBE values at several levels of survival were estimated and were found to decrease with increasing LET. The inactivation cross sections were calculated from the final slope of dose-response curves and were found to increase with increasing LET. CONCLUSIONS: The RBE decreases with increasing LET in the range between 440 and 1600 keV/microm for the two types of radiations forming a single line when plotted together, pointing towards LET as the single determinant of RBE. The inactivation cross section describing the killing efficiency of a single particle at the end of particle range comes close to the size of the cell nucleus.

Trace element concentration distributions in breast, lung and colon tissues.

The concentrations of Fe, Cu, Zn and Se in cancerous and benign tissues of breast, lung and intestine (colon) have been determined. In the cases when the element concentration has not been determined in all samples the Kaplan-Meier method has been used for the reconstruction of the original concentration distributions and estimation of the true mean concentrations and medians. Finally, the log-rank test has been applied to compare the elemental concentration distributions between cancerous and benign tissues of the same organ, between cancerous tissues and between benign tissues taken from different organs. Comparing benign and malignant neoplastic tissues, statistically significant differences have been found between Fe and Se concentration distributions of breast as well as for Cu and Zn in the case of lung tissues and in the case of colon tissues for Zn. The concentrations of all elements have been found to be statistically different in cancer tissues as well as in benign ones when comparing the different organs, i.e. groups 'breast-colon' and 'breast-lung'. Concentrations of Fe and Cu have been found to be statistically different in lung and colon cancerous tissues. For benign tissues of lung and colon a statistically significant difference has been found only for Zn.