Narrow Results

Transition metal elements and others in river water sample supplied by The Japan Society for Analytical Chemistry (JSAC) were determined by PIXE using 2.5 MeV proton beam at the Tokyo Institute of Technology Van de Graaff Laboratory. The relative detection efficiency for each X-ray of element and its recovery were studied in two methods: "Drop and Dry" and "Concentration" methods. Ten elements (V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se and Pb) were determined, being in good agreement with the values certified by JSAC except for Mn. Intensity of K_α X-ray of As and L_α, X-ray of Pb nearly close to each other could be successfully evaluated using isolated L_β X-ray of Pb. Mn was insufficiently recovered to give lower content than the certified value in the present conditions. V that is not listed in the certificate was found to show good agreement with that reported previously. Concentration method using sodium dibenzyldithiocarbamate only could be successfully employed for collecting these elements.

The MicroPIXE technique was employed to reveal detailed distributions of trace elements in the testis, which distinguish the cell type-differences corresponding to the germ cell development (the 14 designated stages of the seminiferous epithelium cycle). Clear elemental imagings were obtained for P and S with a 50 μ m-thick section; S was higher in elongated spermatids in stages VII-VII, where a lower level of P was observed. Elemental imagings of Cu, Fe, Mn, Se, and Zn were obscure compared with P and S, but information about their localization in the seminiferous epithelium was obtained. These results suggest that microPIXE analysis is a powerful technique for investigation of elemental dynamics in the testis, although an improvement of detection for testicular trace elements is required.

Fluctuations of the concentration levels of trace elements play an egregious role in enhancing carcinogenic effect in healthy persons and in the pathogenesis of oral malignancies. Epidemiological studies regarding the role of external carcinogenic agents in oral cancer have documented the involvement of certain trace elements either directly or indirectly. An analysis of trace elements like K, Ca, Fe, Cu, Zn, Se And Pb was done in seventeen oral cancer patients having tobacco habits by drawing their whole blood and determining their concentrations using Energy Dispersive X-ray Fluorescence (EDXRF) spectroscopic technique at Institute of Physics. Bhubaneswar, India which is rapid, efficient, multi-elemental and non-destructive in nature and in principle sensitive to all elements from Na to U. Fifteen healthy non-cancerous persons with tobacco habits were also taken as control. The results of the study group when compared with the control group illustrated that K, Cu and Se concentrations were significantly higher in the oral cancer patients as an effect of deleterious tobacco upon their blood whereas the rest of the elements like Ca, Zn, Fe and Pb did not reveal significant changes.

We made a comparative study of the trace elements in the oral mucosa of 22 patients with oral lichen planus (OLP) and of 100 healthy persons by the PIXE method. Samples were excised from the oral mucosa of the OLP patients (OLP group) and from the buccal mucosa of healthy persons (control group). The results were as follows: Seventeen trace elements and 11 contaminating elements were detected in those oral mucosae. Al, Ti and Pb, which are contaminating elements, were detected in more than 65% of samples from both groups. The mean values of Se and Rb were significantly lower in the OLP group than in the control group. The mean values of the other elements did not differ significantly between the groups. As for the females over 30 years old, the OLP group showed significantly higher values of Zn and Sr than the control group. Their mean values of the other essential and contaminating elements did not differ significantly between the groups, although there was a trend toward higher values in the OLP group. We found by the PIXE method that Zn, Fe and Pd, which are d-transitional elements considered to cause allergic reaction, showed higher values in the oral mucosae of the OLP patients than in those of the healthy persons.

Structural composition of 11 trace elements with Z greater than 13 (Al, P, Si, K, Ca, Mn, Fe, Cu, Zn, Mo, I) was analyzed for the two main groups of human gallstones according to their cholesterol and pigment types by PIXE (Proton Induced X - ray Emission). In both types of stones, the shell and the center were analyzed separately. The gallstones were obtained from 12 patients in wide age group from 22 to 78 years of age during surgical operation. The results show relatively higher values of heavy elements for ages greater than 40. The values of phosphorous in cholesterol type stones are significantly higher than in those of pigment stones. The concentration of calcium in the center of stones is large in comparison with that in the shells. In this paper, a correlation between stone structure and trace elemental concentration has been presented. Comparison of the two essential types of stones (cholesterol and pigment) shows that the center of the pigment stones is very similar to that of the cholesterol type.

Coins are important archaeological objects that can provide useful information regarding preparation methodology and provenance. Their classification plays a fundamental role in dating historical events, in constructing trade routes and in establishing the welfare of population. Several Indian copper coins of different periods have been studied using Energy Dispersive X-ray Fluorescence (EDXRF) spectroscopic technique. The method is rapid, efficient, multi elemental and non-destructive in nature. Concentrations of the major and trace elements like Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As and Pb have been estimated in these copper coins. In the present investigation, an attempt has been made to characterize some Indian copper coins of different periods using EDXRF technique.

Human hairs of cirrhosis, acute viral hepatitis patients and healthy people in Ulaanbaatar, capital city of Mongolia, were analyzed for the presence of heavy elements by PIXE spectrometry using 2.5 MeV proton beam at the Tokyo Institute of Technology Van de Graaff Laboratory. The samples were dissolved in a mixture of nitric acid and hydrogen peroxide. Then a 20μl aliquot was dropped on a Nuclepore Track-etch Membrane. The IAEA Reference Hair IAEA-086 certified reference material was used in order to verify accuracy of the method and the results were in good agreement with the certified values. To determine the interaction among nine elements in hair, correlation coefficients were evaluated for several pairs of elements. In the group of healthy control, no correlation between elements was identified. Opposite to this, the strong positive correlations were observed for Zn and Ca or Fe; Mn and Ca or Ti; Sr and Zn or Fe in the patients hair. In the present study, the mean concentrations of Ca, Ti, As and Sr in Mongolian patients were higher than those in the hair of normal people in Japan, Mongolia, Iran and Indonesia. The levels of Cu, Zn and Mn concentration in hair of normal people were almost the same for all the cohorts.

In a biological body, trace elements including metallic elements play important roles. Knowing their spatial distribution and amounts, we can find out some relations among a physiological role of the trace element in vivo, the function, and the disease appearance. In this study, we investigated a method to obtain elemental distributions in whole brain slice taken from mental disease model mice and control mice using in-air submilli-PIXE camera at Tohoku University. We administered 5-BrdU that was the analogue of the thymidine as a marker to detect a new born cell in especially the dentate gyrus of the hippocampus. We obtained the elemental distributions of the whole brain of subject and control mice. From elemental distributions of the brain of a mental disease model mouse, a brain contained light elements, such as P, S, Cl and K, which were uniformly distributed over the brain. Fe was accumulated in the specific area of brain. Elemental concentration of Fe was more than 10 times higher than that in the other. However, the accumulation of iron in brain slices was not observed in those of control mice. Zn is accumulated in the vicinity in hippocampus. Br was uniformly distributed over the brain. The submilli-PIXE camera will provide a powerful tool for this research.

The early life environment has widespread consequences for later health and disease. To prevent the disease in later life, the assessment of fetal environment is very important. In Japan, birthweight has fallen rapidly during recent two decades. The reduction of birthweight represents reduced fetal nutrition. Deciduous tooth enamel contains pre- and postnatal enamel and its chemical composition reflects the status of metabolism of trace elements during formation period. Deciduous tooth enamel is considered to be a suitable indicator of trace elements exposure in utero. We applied micro-PIXE analysis to investigate the trace elemental content in deciduous tooth enamel. Two deciduous canines from one healthy Japanese boy were used for this study. The enamel section including pre-and postnatal enamel was prepared for micro-PIXE analysis. Five trace elements (Na, Mg, Cl, Zn, and Sr) were detected in the scanning area of tooth. The distribution profiles of 5 elements were obtained as X-ray maps. The distribution profiles of zinc and chlorine were specific, and showed higher concentration in surface enamel. No elements showed different profiles of X-ray maps between pre-and postnatal enamel in this sample. The results of this study suggested that micro-PIXE analysis would be able to estimate the trace elements in prenatal and postnatal enamel, respectively.

The present study examined the index of absorption of trace element (Fe, Cu, and Zn) in different semi-solid nourishment medicines. Various mineral compositions were administered to 7-week-old male rats and semi-solid nourishment medicine from three companies, each using a different gelling agent, were orally administered for two weeks (5 per group). Five rats that were that were fed the standard diet were used as a control group. The rats' excrement excreted after the administration the nutritional supplement was gathered, and the density of trace elements was measured by the PIXE method. The trace element value of each semi-solid nourishment medicine and the standard diet were measured before the experiment, and the intake of trace elements was calculated based on these values. The amount of gut absorption was subtracted from the amount excreted. The groups were compared by the index of absorption.

The knowledge of the intracellular distribution of biological relevant metals is important to understand their mechanisms of action in cells, either for physiological, toxicological or pathological processes. However, the direct detection of trace metals in single cells is a challenging task that requires sophisticated analytical developments. The combination of micro-PIXE with RBS and STIM (Scanning Transmission Ion Microscopy) allows the quantitative determination of trace metal content within sub-cellular compartments. The application of STIM analysis provides high spatial resolution imaging (< 200 nm) and excellent mass sensitivity (< 0.1 ng). Application of the STIM-PIXE-RBS methodology is absolutely needed when organic mass loss appears during PIXE-RBS irradiation. This combination of STIM-PIXE-RBS provides fully quantitative determination of trace element content, expressed in μg/g, which is a quite unique capability for micro-PIXE compared to other micro-analytical methods such as the electron and synchrotron x-ray fluorescence. Examples of micro-PIXE studies for sub-cellular imaging of trace elements in various fields of interest will be presented: in patho-physiology of trace elements involved in neurodegenerative diseases such as Parkinson's disease, and in toxicology of metals such as cobalt.

Naturally shed deciduous teeth are potentially useful as a biomarker of environmental exposure. To assess the prenatal environment of child, we tried to present the neonatal line on the elemental maps and investigate the trace elements in pre- and post-natally formed tooth enamel using micro-PIXE. Generally, the neonatal line is observed more clearly in the tooth from child who has some difficulties at birth. In this study, five deciduous teeth from five children with developmental disorders were used for analysis. Seven trace elements (Na, Mg, Si, Cl, Fe, Zn, and Sr) were detected in enamel of all five teeth. The line, it was thought neonatal line, was observed on the elemental map of Ca and P in the tooth from the child with serious birth complications. In order to compare the elemental concentration between pre- and post-natal enamel, concentration variation of elements were projected along the line perpendicular to the neonatal line. Lower Ca concentration in prenatal enamel was observed. By tracing the location of neonatal line on the other elemental maps, the concentrations of detected trace elements were compared in the same way. The differences of concentration of these trace elements between pre- and post-natal enamel were not clear because of much statistic variation. We could determine the trace elemental profiles and concentrations around the neonatal line in the enamel from the child with serious birth complications.

The purpose of our research is to identify causative metals by using particle-induced X-ray emission (PIXE) method to directly analyze trace elements in the oral mucosa with oral lichen planus (OLP). Subjects were 72 patients with OLP, and the patients are 25 men and 47 women, with a mean age of 60.1 years (OLP group). The control is elemental analysis data by PIXE method of 100 cases of the oral mucosa of healthy persons (control group). Seventeen essential elements and 12 contaminating elements were detected from the oral mucosa of the OLP and control groups. As to appearance ratio of elements in oral mucosa, among the contaminating elements, levels of Al, Ga, Sb, Hg and Pb were significantly lower, whereas Au and Y were significantly higher in the OLP group than in the control group. About concentration of elements in oral mucosa, the contaminating elements in the oral mucosa of the OLP group had a lower appearance ratio than in the control but each of the contaminating elements was more abundant. Among 25 subjects in the OLP group and seven in the control group, serum, oral mucosa and saliva were collected from the same individual. Abundance in serum and saliva varied depending on the element, but in general, a tendency was seen for contaminating elements to be more abundant in saliva than in serum and for essential elements to be more abundant in serum than in saliva.

Cultured pearls are formed in pearl sacs comprising epithelial cells transplanted into mother-of-pearl. The formation mechanism is complicated and is still not fully understood. Previous studies have shown that the pearl formation is influenced by aquaculture environment and physiological activity of shellfish. The elemental compositions of seawater and freshwater pearls are significantly different. In this work, we used the particle-induced X-ray emission (PIXE) technique to perform elemental analysis of six types of pearls: ordinary and blue Akoya pearls, black-, gold-, and white-lipped oyster pearls, and freshwater Biwako pearl. We investigate the influence of trace elements in aquaculture environments on formation of mother-of-pearl or color. The Mn/Sr or Fe/Sr ratio for the freshwater pearl was found to be significantly higher than that for the seawater pearl. Comparing the sweater pearls, the gold-lipped oyster pearl has high value of Mn/Sr ratio. The Fe/Sr and Cu/Sr ratios for two Akoya pearls harvested from the Sea of Japan are relatively high compared with black-, gold-, and white-lipped oyster pearls from the South Sea.

In this paper, we performed PIXE analysis of trace elements in freshwater pearls cultured in four different areas: Lake Biwa (Japan), Lake Kasumigaura (Japan), an unidentified lake in China, and Kentucky Lake (USA). We investigated the difference of trace elements contained in the four pearls from different aquaculture environments. The observed trace elements are Mn, Fe, Cu, Zn, and Sr. The major trace elements are Mn, Sr for all the samples. From comparison of the proportions of elements contained, we found the following features: (1) The Kasumigaura pearl has a nucleus with a high Mn/Sr ratio, (2) The Biwako pearl is low in iron content, and (3) The American pearl has high in Fe/Sr, Cu/Sr, and Zn/Sr ratios.

The aspects of the PIXE technique in the Van de Graaff Laboratory of Fudan University are reported. The analytical precision is within 5% when handling with care and within 10% in routine analysis. Some recent applications of PIXE are presented, including the pathogeny analysis of Kashin-Beck’s disease and cancer, hair analysis of pregnant women and an unknown primate, and PIXE analysis in DNA study.

Micro-PIXE has been used to measure the trace element distribution in otoliths from several species of ocean fish, in order to investigate its possible use in stock discrimination. Trace elements detected include Sr, Fe, Mn, Ni, Zn, Cu, Se, Cd, Br, Hg and Pb. Trace elements Na, K, Cl, S and Cl were detected with the electron microprobe. The high sensitivity of PIXE demands a meticulous sample preparation procedure to avoid contamination problems. Practical problems associated with the application of the technique were investigated in detail. Preliminary results indicate that most trace elements except Sr, are present at close to the limits of detection at few ppm, but biologically significant data can be obtained for stock discrimination applications.

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.

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.

Typical elements in PET bottled mineral water and in running water of public waterworks near by our cyclotron center was investigated by PIXE. We can detect typical elements in water sample using only a pipette. After water sample was preserved in a brown-glass vessel or a clear-glass vessel, Ba and Ti consisting in the vessels were detected in water samples. Concentration of typical elements in running water is found to be equal to that in PET bottled mineral water.