International Journal of PIXE

The distribution of elements in human spinal cord was investigated on unfixed frozen cord material using PIXE technique. Distribution of Cu, Zn and Fe were not uniform in the cross section of the spinal cord and concentrations of these elements were higher in the anterior gray horn than in the other areas, while K and Cl distributed uniformly. The content of K changed along the spinsl cord from the cervical to the lumbar level. These findings are discussed in relation to current understanding of the physiology of the spinal cord.

The sodium alginate extracted from sargassum of South China Sea significantly inhibited the absorption of Sr in human gastrointestinal tract. Because of the identical metabolism dynamics of radioactive Sr and stable Sr, oral medication experiments have been performed by using stable Sr as a tracer. Fifteen adult healthy subjects (10 males and 5 females) were involved and divided into two groups. Concentrations of Sr, Ca, Fe, Cu, and Zn in serum and urine (24 hours) at different times after oral medications were measured by PIXE. It was found from the PIXE results that Sr in serum and in urine were reduced (78 +/− 8.9)% and (78 +/− 11)% respectively by sodium alginate. A reasonable dosage of sodium alginate had little influence to the absorption of Ca, Fe, Cu, and Zn.

This work is to analyse trace elements in skin and muscle of a broken woman leg. Using PIXE technique,tissues of skin and muscle from doubtful point and normal part were analysed quantitatively. As the results,the contents of Fe and Zn in the doubtful point are higher than those in normal part, while other elemental contents are not remarkably different. This fact suggests that the doubtful point in skin and muscle might contain extravasated blood after wounded by some tools.

Seven autopsied cases were studied for the evaluation of individual history of exposure to environmental contaminants based on the elemental profile of hilar gland by PIXE and lung tissue by AAS. The results well characterized their occupational history, especially from Cr, Al, Si and As detection. Moreover, it might be possible that these analyses would provide data to suspect the chemical form of each element in deposited particles of lung parenchyma, since the solubility could reflect the different profile of element between hilar gland and lung parenchyma. In addition to these retrospective analyses using the materials obtained from autopsies, it is possible to assess the individual risk using small quantity of hilar gland or lung tissue obtained by biopsy or surgical resection.

Alterations of heavy metal concentration in inoculated Sarcoma -180 after irradiation by 6MeV electron beam at the doses of 5Gy were evaluated in vivo in BALB/c mice, by Particle Induced X -ray Emission (PIXE).

Analysis was performed for K, Cl, S, Fe, Zn and Cu. In the irradiation of 5Gy, the concentration of K and Cl have revealed the fast incremment at 1 hour after irradiattion and the fast decremment after that time. As for the S, Fe, Cu and Zn, their concentrations have revealed the fast incremment at 1 hour after irradiattion and the slow decremment from 1 hour after irradiation (except for slow increment from 1 hour to 1 day after).

The alteration of concentration levels for two minor elements (K and Ca) and 7 trace elements (Mn, Fe, Cu, Zn, Se, Rb and Pb) in serum and packed blood cells was investigated. The samples originated from 35 patients that had a myocardial infarction and from 29 healthy individuals. The Mn and Pb concentrations were only determined in packed blood cells. Particle-induced X-ray Emission (PIXE) was used to determine the elemental concentrations in the various samples. In blood serum the Fe, Cu and Zn concentrations were found to be altered from normal, while in packed blood cells significant differences were encountered for Ca, Mn, Fe, Cu, Se and Pb. Factor analysis performed on the serum and packed blood cells data matrices revealed one factor for each sample type which allowed distinguishing between healthy and pathological individuals. Furthermore, the elements that permit this discrimination are different for the two data sets. The elements related to this discrimination factor were Fe and Cu for serum and Ca, Mn, Fe, Cu and Zn for packed blood cells.

Despite intensive investigation, normal and abnormal calcification mechanisms are still poorly understood.

In our study we measured the change of main and trace element concentrations across the calcification area of the mandibular cartilage of domestic pigs of different age.

The PIXE method was employed for the analysis of the cartilage samples, using a proton beam with an energy of 1700 keV.

Concentration values of the elements P, S, Cl, K, Fe, Ni, Cu, Zn, Br, Rb, and Sr were evaluated from the measured spectra.

Significant changes of elemental contents across the calcification area could be observed.

Tin (Sn) is one of the causative elements of the environmental pollution. As no certified reference materials for Sn are presently available, existing reference materials were analyzed for Sn by two independent analytical techniques; atomic absorption spectrometry (AAS) and neutron activation analysis (NAA). The results obtained by both methods were in agreement except for mixed diet which contains Sn in the range of 50 μ g/g. Further, tin concentrations in human and animal organs have been examined by AAS. Among organs tested tin concentrations in testes were the highest, 2.08±0.62 μ g/g dry weight (mean ±SD, n=12) in humans, and 1.45±0.55 μ g/g (n=8) in mice.

To investigate the etiology of Alzheimer’s disease, we administered aluminum to healthy rats and examined the aluminum uptake in the brain and isolated brain cell nuclei by particle-induced X-ray emission (PIXE) analysis.

Ten days after the last injection, Al was detected in the rat brain and in isolated brain cell nuclei by PIXE analysis. Al was also demonstrated in the brain after 15 months of oral aluminum administration. Moreover, Al was detected in the brain and isolated brain cell nuclei from the patients with Alzheimer’s disease. Silver impregnation studies revealed that spines attached to the dendritic processes of cortical nerve cells decreased remarkably after aluminum administration. Electron microscopy revealed characteristic inclusion bodies in the hippocampal nerve cells 75 days after the injection. These morphological changes in the rat brain after the aluminum administration were similar to those reportedly observed in the brain of Alzheimer’s disease patients.

Our results indicate that Alzheimer’s disease is caused by irreversible accumulation of aluminum in the brain, as well as in the nuclei of brain cells.

A 22-year-old male was hospitalized with mild fever, diarrhea, abdominal pain, and weight loss and was diagnosed as having Crohn’s disease. Total parenteral nutrition was administered to reduce bowel inflammation and correct nutritional disturbances. During long term intravenous hyperalimentation, the serum zinc level fell to 27 μg/dl and the patient developed acrodermatitis enteropathica and pancreatitis. Zinc supplementation resulted in the disappearance of these complications. Erythrocyte CA I-specific activity was 0.35 units/mg before zinc replacement, and recovered to 0.62 units/mg when the serum zinc level reached 124 μg/dl. CA I is present not only in erythrocytes but also in gastrointestinal epithelia, vascular endothelium, and sweat glands. To date there are no specific laboratory tests that reliably document tissue zinc deficiency. However, erythrocyte CA I activity may reflect the actual zinc status.

Elemental composition in synovial fluids from six patients with various arthritides was investigated to clarify the difference among the clinical cases using PIXE analysis and ion chromatography. Cl, K, Ca, Mn, Fe, Ni, Cu, Zn and Br were detected in the PIXE spectra and Cl⁻, K⁺, Na⁺ and uric acid ions were determined by ion chromatography. These results were discussed in relation to the diagnostic findings.

We used the particle induced X-ray emission (PIXE) spectrometry to perform elemental analysis of liver biopsy materials from patients with three different kinds of liver diseases; acute hepatitis, chronic hepatitis and liver cirrhosis. We compared the Cu/Fe and Zn/Fe concentration ratios in these different liver diseases. There was no significant difference in the ratios because of the kind of liver disease. However, we found a positive correlation between the Cu/Fe concentration ratio and both serum GOT (glutamate oxalacetic transaminase) and GPT (glutamate pyruvate transaminase) levels in 14 patients with liver diseases.

Photodynamic therapy (PDT) is a promising approach to the local destruction of malignant tumours. This method is based on the partially selective retension in tumor tissue of the photosensitizers which have photodynamic effect. It is important for PDT to determine the photosentizer concentration in tumor and in normal tissue. We quantitatively analysed the concentration of the metallic phthalocyanines, a class of photosensitizers now recognized as “second generation” PDT drugs and studied its action in different time by PIXE technique. The paper shows also the correlation between trace elements and cancer.

The particle induced X-ray emission analysis is applied to mark (or to localize) a cancer lesion from its benign environment in animal experiments. As a photosensitiser, we have used hematoporphyrin derivative (HPD) and in order to make HPD visible to PIXE, we synthesize HPD with rare earth metals to form lanthanide-HPD to enhance the localizing efficiency tremendously and PIXE is used as a straightforward detection method to find the successfulness of the synthesis. In theory, this approach can be used to probe carcinogenesis at cell levels. To increase the cure effects of lanthanide-HPD, we add ZYX to enhance the pharmaceutical effectiveness. ZYX, our code name for a group of drugs and chemicals, is mostly of the Chinese herb extraxctions but some has different origin. We explain the present approach with a specific experiment, Dysprosium-HPD (Dy-HPD) as a localizer, and conclude this article with some comments and perspectives.

It has been previously shown that activated alveolar macrophage in idiopathic interstitial pneumonia (IIP) played an important role in the process of fibrosing, but the initial agent which activates alveolar macrophages has not been proved. The present study was designed to make quantitative analyses of trace elements in the lung tissue speciments of IIP patients and normal controls. Particle induced X-ray emission (PIXE) was used. The IIP group consisted of 11 patients and the Control group, which had no apparent history for dust inhalation and lung diseases, consisted of 9 subjects. More silicon and magnesium were found in the IIP group than in the normal controls. These data suggested that inhalation of silicon and magnesium might be one of the etiologic factors of IIP.

The application of PIXE and micro-PIXE methods for the description of human aortic wall mineralization including its dynamics is presented. The data was collected both from human autopsy samples and from animal material. The mean concentrations of P, S, Cl, K, Ca, Fe, Cu, Zn, Br, Sr and Pb were determined in tissue samples and in the aortic wall sections. On the basis of PIXE results the following conclusion may be drawn: the concentrations of Ca, Zn, Sr and Pb increase while that of S, Cl and K contents decrease when the mineralization of the vessel wall (determined histochemically) develops. The micro-PIXE method enabled: (1) the determination of the elemental composition of both inorganic and organic materials in the sample, (2) the identification of different Ca—P compounds on the basis of the Ca/P ratio, (3) the investigations of the involvement of other elements in the development of mineralization process (4) the determination of the deposit radii on the basis of Ca concentration and (5) the generalized analysis on the inorganic deposit growth using mathematical description.

The contents of multi-elements in whole blood from 115 patients with 7 different types of acute leukemia and 38 well matched healthy controls have been determined by means of proton induced X-ray emission (PIXE). The number of available analyzed elements was as many as 11, mainly due to the use of a 100 um thick Cr funny foi1 as an absorber. The contents of elements Cu, Ca, S, P, Si and the ratio of Cu to Zn (Cu/Zn) were higher and those of elements Zn, K, Fe, Al and Rb were lower with high significant differences (P<0. 01) in acute leukemia patients than in norma1 controls. The results indicate that the contents of Cu, Zn, and the ratio Cu/Zn are useful indices of disease activity. The elements of Al and Rb may play important roles in acute leukemia etiology,

Environmental and health impact of coal burning power plants due to particulate emission is considered. As a result of coal burning large number of toxic elements are released into the atmosphere. The quantity released depends on the particulate control system, furnance design, mineral content of the coal and existing emission control standards.

The pathways of toxic elements from coal burning power plants to man as well as dose-response effects could be considered by the applications of PIXE and μ-PIXE as analytical techniques. It is demonstrated that, in addition to concentration levels, information on concentration profiles (surface enrichment) of elements on fly ash particles, having diameter of few micrometers or less is essential.

Proton Induced X-ray Emission (PIXE) and Instrumental Neutron Activation Analysis (INAA) techniques were used to measure the contents of 45 elements in 150 air-filter samples collected by cascade impactor with 8 stages at 10 sites in Beijing-Tianjin area of China during the periods of the winter of 1983 and the summer of 1984. It was noticed that the toxic elements such as As, Sb, Se, Pb, Hg, Cu and Ni were mainly enriched in fine particles with diameter less than 2 um. The major seven sources of coal burning, soil dust, oi1 burning, sea-salt aerosol, motor vehicle emission, limestone dust and industrial refuse attributing to the pollution in Tianjin area were identified by Chemical Elements Balance method (CEB). Among them the most important sources were the soil dust and the emission from coal-combustion followed by contributions from limestone and industrial refuse.

Rubidium (Rb) concentration in different samples collected from Keshan disease (KD) area of Sichuan Province has been determined with PIXE and NAA (Neutron Activity Analysis), and compared with that in three non-KD areas. About 200 erythrocyte samples of healthy children aged from 6 to 11 were collected from four different areas with various selenium status. 20 rice samples and 6 soil samples were taken from two of above four areas. The results showed that Rb content of erythrocyte of children in KD area (Dechang county) was three times that in the other three non-KD areas. The Rb contents of rice and soil in KD area were higher than that in non-KD areas, too. The abnormal high Rb concentration in erythrocyte of children depended on the Rb intake and the Rb level of the living environment.

The recent methodological developments and particularly the recent applications of nuclear analytical techniques (mainly PIXE and INAA) for measuring minor and trace elements in various types of environmental samples are reviewed. The sample types covered range from atmospheric aerosols over miscellaneous air topics (e.g., emissions, wet and dry deposition) to various solid environmental materials and samples from the aqueous environment. A fairly comprehensive overview is given of the research on atmospheric aerosols. For the other sample types, the trends in the research are indicated and selected examples of applications are presented. It is shown that the nuclear analytical techniques are very valuable for the multielement analysis of solid environmental samples. Furthermore, PIXE is particularly suitable for analyzing atmospheric aerosol samples.

The atmospheric aerosol samples are collected in Beijing using a ten-stage cascade impactor sampler, and the elemental concentrations are analyzed by the PIXE analytical method. The parameters of particle size distributions are determined by the use of log-normal plots and the least-squares minimization. From these parameters the total amount of deposit in a day at the naso-pharyngeal, tracheo-bronchial and pulmonary are evaluated based on the deposition and retention models.

Longitudinal distribution of ground level aerosol concentrations have been measured in the neighbourhood of an emission source of mixed character by the PIXE method. The source was located in a valley in hilly terrain. The elements observed are divided into two groups according to the magnitude of the fine-to-coarse concentration ratio. The elements of small ratios are crust-related elements and the concentration of these elements show strong decrease with transport distance. The elements of large ratios are oil-related elements and the concentration are relatively stable during short-range transport.

Direct application of many existing reference materials in micro-analytical procedures such as energy dispersive x-ray fluorescence (EDXRF), particle induced x-ray emission spectroscopy (PIXE) and ion probe techniques for the determination of trace elements is often impossible or difficult because: 1) other constituents present in large amounts interfere with the determination; 2) trace components are not sufficiently homogeneously distributed in the sample. Therefore specific natural-matrix reference materials containing very low levels of trace elements and having high degree of homogeneity are required for many micro-analytical procedures. In this report, selection of the types of environmental and biological materials which are suitable for micro-analytical techniques will be discussed.

More than 3,000 aerosol samples have been collected since 1986 in Kyoto under various meteorological and environmental conditions, including episodic air pollution events such as heavy air pollution, Kosa dust, very clean air, etc. The elemental concentrations of these aerosol samples were determined by PIXE techniques, and elemental concetration data were used to estimate a source contribution of aerosols by applying a receptor model.

The concentrations of Si, K, Ca, Ti and Fe in both coarse and fine fractions increased tremendously at Kosa event. The maximum source contribution of soil dust amounted to 140 μg/m³ for a six hour average during a Kosa event. On the other hand, the concentrations of S, Zn, Pb and Cu in the fine fraction increased remarkably during heavy air pollution and photochemical smog events.

Norway spruce is fumigated with O₃, SO₂, and NO₂ in open-top chambers. The spruce needles from the first two years of fumigation were analysed by means of PIXE. A total of 14 elements were found in concentrations above the detection limits in the major part of the around 150 samples analyzed. The results were used in an analysis of variance showing, slightly increased levels of S and Zn in needles from trees exposed to fumigation with all three gases.