RESUMEN
There are some papers in the literature on the trace element contents of fetal livers of 20-wk gestation time and over. However, there is very little information on this subject for fetal livers of less than 20-wk gestation. We have initiated a program on the measurement of trace elements in fetal livers of 12-22-wk gestation, using thick-target X-ray fluorescence analysis.The liver samples were obtained from freshly aborted fetuses. After removing blood from the samples, they were chopped into small pieces and freeze dried. The resulting material was ground into fine powder and compressed into 3-mm thick pellets, with boric acid backing. A similar pellet was also made of NBS-Bovine Liver-which was used as the standard for calculating the absolute concentrations of different trace elements.The measurements were carried out using a commercial Wave-Length-Dispersive XRF-System. Different X-ray tubes were used for different sets of elements in order to maximize the detection sensitivity. The results are compared with those of fetal liver of longer gestation and adult livers.
RESUMEN
The effect of diabetes on trace elements concentration in blood of experimental animals has been studied by thin-target X-ray fluorescence analysis. Balb/C young adult mice, 6-8 wk old, were used in the study. About 100-200 µL venous blood was taken from each mouse for trace element analysis. The measurements were carried out on a commercial Wave-Length-Dispersive XRF System, with different X-ray tubes being used for maximizing the detection sensitivity of different groups of elements.Later on, the mice were made diabetic by an intravenous injection of Streptozotocin (250 mg/kg). Then, 2 and 3 wk after the injection, 100 µL of venous blood was drawn from each of the mice and analyzed for trace element concentration. In this way we were able to study the changes in blood trace elements caused by diabetes.The results and advantages of using experimental animals, under controlled conditions, to study trace element variations caused by different diseases, are discussed in the paper.
RESUMEN
In order to get some information on the possible causes of graying of hair, we have used the technique of X-ray fluorescence (XRF) analysis for comparing the trace element contents of natural color and gray hair from a number of subjects. The technique of XRF was preferred to other analytical methods for this kind of comparative studies since it appeared to be simple, convenient, quick, and contamination free.Natural color and gray hair from each subject were obtained from the same scalp region. The hair samples were washed in the recommended fashion. The natural color and gray hair from different subjects were mounted separately on hollow plastic cylindrical sample holders, assuring that the hair were parallel to, and not on top of one another. The samples were analyzed in a commercial wave length dispersive XRF system, with different X-ray tubes being used for obtaining maximum sensitivity for different elements. The scattered X-ray peak from each sample was also monitored and gave a measure of the sample volume being investigated. So far, hair samples from 10 subjects have been analyzed. Their results are presented in the paper, and advantages of XRF, for trace element analysis on hair are discussed.