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1.
Many biomedical experiments require the qualitative and quantitative localization of trace elements with high sensitivity
and good spatial resolution. The feasibility of measuring the chemical form of the elements, the time course of trace element
metabolism, and conducting experiments in living biological systems are also important requirements for biological trace element
research. Nuclear analytical techniques that employ ion or photon beams have grown in importance in the past decade and have
led to several new experimental approaches. Some of the important features of these methods are reviewed here along with their
role in trace element research. Examples of their use are given to illustrate potential for new research directions. It is
emphasized that the effective application of these methods necessitates a closely integrated multidisciplinary scientific
team. 相似文献
2.
A particle-induced X-ray emission (PIXE) analysis method is presented, which allows measurement of eight elements (i.e., K,
Ca, Mn, Fe, Cu, Zn, Se, and Rb) in human brain samples of only a few mg dry weight. The precision and accuracy of the method
were investigated by analyzing animal brain matter with both PIXE and instrumental neutron activation analysis (INAA). The
method was applied to measure the 8 elements in 46 different regions of 3 human brains. The sections analyzed originated from
either the left or the right cerebral hemisphere, brain stem, and cerebellum. For one of the brains, sections were also analyzed
from 26 corresponding regions of both hemispheres. For all elements, similar concentrations were found in the corresponding
areas of the left and right sides of the brain. The concentrations (in μg/g dry weight) of the elements K, Fe, Cu, Zn, Se,
and Rb were consistently higher in cortical structures than in white matter. Deep nuclei and brain stem, which have a mixed
composition, showed intermediate values for K, Zn, Se, and Rb. A hierarchical cluster analysis indicated that the various
brain regions clustered into two large groups, one comprising gray and mixed matter regions and the other, white and mixed
matter brain areas. 相似文献
3.
T. Cichocki B. Gonsior J. Glazur M. Höfert L. Jarczyk E. Rokita A. Strzałkowski M. Sych 《Biological trace element research》1987,13(1):167-177
The elemental composition of rabbit liver was determined by the PIXE and micro-PIXE methods. The mean concentrations of P,
S, Cl, K, Fe, Cu, Zn, and Rb measured by both methods were similar. The latter method also allowed for localization of elements
within lobule territory. It has been found that some elements are more prevalent in the veins (Cl, Fe) and others in the liver
parenchyma (P, Cu, Zn). Moreover, Zn showed the characteristic intralobular distribution. Some methodological aspects of microbeam
application to biological materials were also discussed. 相似文献
4.
The use of nuclear analytical techniques for environmental studies in South America is selectively reviewed since the time of earlier works of Lattes with cosmic rays until the recent applications of the PIXE (particle-induced X-ray emission) technique to study air pollution problems in large cities, such as São Paulo and Rio de Janeiro. The studies on natural radioactivity and fallout from nuclear weapons in South America are briefly examined.
相似文献5.
T. Kupila-Rantala J. T. Dabek M. Hyvönen-Dabek 《Biological trace element research》1996,55(1-2):173-179
A new technique for investigation of elemental concentrations in subfractions of blood plasma is presented. The method is
composed of the ultrafiltration of plasma in the presence of ethylenediaminetetraacetic acid (EDTA) and the measurement of
the elemental composition by proton-induced X-ray emission (PIXE). The blood samples were collected from both healthy persons
and patients suffering from breast cancer. The main emphasis in this study was on the determination of loosely bound copper
(Cu) in plasma subfractions containing substances with molecular mass under 10,000, but zinc (Zn) and iron (Fe) contents of
these fractions were also determined. The detection limits obtained with this method for Cu, Zn and Fe were ≈10 ppb (wet wt). 相似文献
6.
Durosinmi M. A. Ojo J. O. Oluwole A. F. Ononye A. F. Akanle O. A. Spyrou N. M. 《Biological trace element research》1994,(1):357-361
The concentrations of a number of elements are determined in the plasma and erythrocytes of 21 Nigerians (11 females, 10 males)
with symptomatic affective disorders (11 depressives, 10 manics) and in 40 normal controls using proton-induced X-ray emission
(PIXE) analysis. The study shows that there is significant elevation of plasma K and Zn, as well as the erythrocyte S in the
patients relative to the controls. The plasma and erythrocyte Cu, and the erythrocyte P, Ca, Fe, and Zn are significantly
lower in the patients compared to the controls. However, the plasma levels of Ca, S, Fe, and Br are similar in both the patients
and the controls. Similarly, the concentrations of K, Br, and Rb show no significant difference in the erythrocytes of patients
and controls. 相似文献
7.
Study of trace elements in blood of cancer patients by proton-induced X-ray emission (PIXE) analysis
Durosinmi M. A. Ojo J. O. Oluwole A. F. Akanle O. A. Spyrou N. M. 《Biological trace element research》1994,(1):351-355
Proton-induced X-ray emission (PIXE) analysis was employed to determine the concentrations of six elements in the plasma and
erythrocytes of 18 cancer subjects (15 males and 3 females) with neoplastic disorders and in 70 controls (35 males and 35
females). It was found that the concentrations of Br, K, and Zn were significantly elevated in the erythrocytes of the cancer
subjects compared to the controls, whereas the concentration of Fe was significantly depressed, but with no difference observed
in the concentration of Ca. In the plasma, the concentrations of Br, Cu, Ca, and K were significantly elevated, whereas the
concentrations of Fe and Zn were found to be significantly depressed compared to the controls. 相似文献
8.
M. Peltomaa K. Mattila J. Wolf M. Hyvönen-Dabek 《Biological trace element research》1992,34(3):249-255
The trace elements of both calcified atherosclerotic plaques and plaque-free vessel walls of the carotid bifurcation from
31 autopsies were investigated using the proton-induced X-ray emission (PIXE) method. The trace elements studied were phosphorus
(P), calcium (Ca), chrome (Cr), iron (Fe), copper (Cu), zinc (Zn), lead (Pb), selenium (Se), bromine (Br), strontium (Sr),
and rubidium (Rb). All samples contained Fe and Zn. Mercury (Hg) was not detected in any of the samples studied. All plaque-free
samples contained Cu and almost all Br and Ca, none Sr. All calcified atherosclerotic plaques contained Ca and almost all
Br and Sr. The relative levels of Ca were higher in the calcified plaques than in the plaque-free vessel walls. The relative
value of Ca in calcified and uncalcified samples was greatest in the group who had died because of cardiovascular disorders
and smallest in the group who had died from other causes. There was a strong positive correlation between the Ca and Sr of
the plaque samples and between the P and Br of the plaque-free samples. 相似文献
9.
Shuichi Kaminogawa Kunio Yamauchi 《Bioscience, biotechnology, and biochemistry》2013,77(12):2343-2348
A γ-casein-like fraction (FIV) was isolated from the β-casein A hydrolyzate by milk protease and compared with γ-casein. The mobility in polyacrylamide gel electrophoresis, sedimentation coefficient, molecular weight, amino acid composition and terminal amino acids of FIV were almost coincided with those of γ-casein. It is suggested that γ-casein is possibly a product of β-casein hydrolysis by milk protease. 相似文献
10.
Olabanji SO Adesina SK Ceccato D Buoso MC Moschini G 《Biological trace element research》2007,116(2):171-184
Sixteen medicinal plants used for cleaning teeth in southwestern Nigeria were analyzed using the particle-induced X-ray emission
(PIXE) technique. These medicinal plants have other therapeutic uses, but the emphasis and main focus were on their beneficial
effects on human teeth. PIXE measurements were carried out using 1.8 MeV collimated proton beam from the 2.5 MV AN 2000 Van
de Graaff accelerator at the Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Padova Italy. The results
showed the presence of 18 different elements at different concentrations, 2 plants had traces of gold, and none of the plants
contained any toxic heavy metals. The metabolic roles of the detected elements were discussed especially as they affected
the formation, growth, development, and protection of human teeth. The results of this study are presented and discussed. 相似文献