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The concentration of trace elements in samples of both colorectal cancer tumors and normal tissues of a Mexican population were irradiated for 30 s and 4 h and their elemental content were measured by instrumental neutron activation analysis. Ca, Cu, Co, I, Mg, Se, Fe, Zn, Hg, Ba, and Cr were analyzed. Alterations in Co, Fe, I, and Ba were found in tumors with respect to normal tissues.
We examined interaction of the trace element zinc with copper and lead. In sickle cell anemia, the usual situation is one of mild to moderate zinc deficiency owing to renal loss of zinc. Zinc deficiency seems to produce a mild overburden of copper and an increased ceruloplasmin level, probably by enhancing copper absorption. With zinc therapy, this process is reversed. Pharmacological doses of zinc, when administered in a way to ensure effectiveness (without food) will usually lead to copper deficiency. We have taken advantage of the copper-depleting effect of zinc to design a new therapy for Wilson's disease. Zinc, by inducing intestinal metallothionein, inhibits absorption of copper from food, and inhibits reabsorption of endogenously secreted copper, thereby producing a negative copper balance in Wilson's disease. Once we are certain that zinc blocks accumulation of copper in the liver of Wilson's disease patients, zinc therapy will be available as one approach for treating this fatal disease. The animal literature indicates that zinc protects against lead toxicity when both elements are given orally, no doubt through the intestinal metallothionein mechanism. In preliminary experiments in rats, we have not been able to show that toxicity from lead that arrives into the body through a nonoral route is affected by oral zinc supplements.
Although it is widely recognized that essential trace elements are required for the differentiation, activation and performance of numerous functions of immune cells, the specific roles of these inorganic micronutrients in these processes remain largely undefined. New insights about the participation of zinc, iron and copper in the selection, maturation and early activation events of the immune cells have been gained by judicious use of available tools in analytical cell biology, molecular genetics and array technology. Also, randomly controlled clinical and community trials demonstrate that zinc supplementation can enhance immunocompetence and decrease the incidence and severity of some infections in individuals with diagnosed or suspected mild zinc deficiency. These exciting results provide an impetus to evaluate the potential benefits of supplementation programs for individuals and groups with suboptimal trace element status as a cost-effective means of reducing the risk of infectious diseases.
Titanium implants were placed bilaterally in the proximal tibia of thirty-six adult male rabbits to demonstrate the relation between trace element selenium and titanium implants osseointegration. The animals were randomly divided into the control group and the selenium adding group. There were eighteen animals in each group. In experimental group, Na2SeO3 10 micrograms/kg body weight was given intramuscularly everyday for 6 days postoperatively, Measurement of trace element selenium contents, histologic findings and mechanical testing were applied to evaluate the effect. The results showed that trace element selenium contents of bones around implants were positively related to the strength of the implant fixation. Selenium could obviously speed up the formation of implant osseointegration and significantly improve the strength of the implants fixation compared with the control group at 1 week and 4 weeks after implantation.
A double-blind parallel group study was carried out in patients with mild to moderate hypertension to assess the effects of 6 mg piretanide once or twice daily, in comparison to 50 mg hydrochlorothiazide plus 5 mg amiloride once daily, on serum trace-element levels over a period of three months. The results showed that for most of the trace elements investigated (zinc, iron, copper, manganese and cobalt) no relevant changes were seen. Only serum iron values (medians) showed a slight drop (p less than 0.05) with 6 mg piretanide twice daily. The results indicate that a three-months' therapy with piretanide or with a thiazide-potassium sparer diuretic combination is safe without producing any disturbances in the serum levels of trace elements.
It is shown that administration of certain trace elements in maximum allowable concentrations induces changes in metabolism and functionation of cells in the culture. Zinc, nickel, cobalt, cadmium and fluorine are stated to inhibit mitotic activity of HeLa cells by the end of 24 hours of their action. Parallel with this they promote a decrease in H3-thymidine incorporation into DNA. Besides these substances delay various stages of the mitotic cycle for cells.
UNLABELLED: Serum copper (Cu), zinc (Zn) the Cu/Zn ratio (Cu/Zn) and selenium (Se) were evaluated in 84 patients with non-small cell lung cancer (NSCLC) before surgery. Serum carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC) and sialyl Lewis X-i antigen (SLX) levels were also determined in the same cases. The cut-off values of Cu, Zn and Se were established to create two categories with equal numbers of patients. We investigated the clinical and prognostic usefulness of assays of serum trace elements (Cu, Zn, Cu/Zn and Se) and compared levels of serum trace elements and serum tumor markers (CEA, SCC and SLX) in NSCLC patients. Furthermore, we evaluated the usefulness of serum trace elements, when compared with tumor markers, in assessing prognosis for NSCLC. IN CONCLUSION: (1) a preoperative increase in Cu/Zn level predicted tumor progression more effectively than changes in Cu or Zn levels; (2) Se levels seemed to vary with age, but there was no relationship between Se level and disease stage; (3) the measurement of Cu/Zn was useful for assessing both prognosis and extent of the disease in NSCLC patients, similar to the measurement of serum tumor markers such as CEA; and (4) the measurement of the Cu/Zn had prognostic significance, but was inferior to disease stage in predicting outcome. Cu and Zn in serum are storable and the determination of Cu/Zn level is so simple and inexpensive that it can be helpful in determining clinical stages and predicting the prognoses of NSCLC patients.
Trace elements were examined spectrophotometrically in 45 patients with chronic hepatitis (persisting--31; chronic--14). Lead and cadmium showed a significant increase both in the healthy and hepatitis patients. A reduction of zinc and increase of copper was found in patients with chronic hepatitis. Changes in the content of microelements depended on the severity of the disease.
The survey presents current knowledge on antioxidant defence systems and on the role and meaning of trace elements in these systems. From this point of view the most important elements include transient metal iron and copper, and there after selenium, zinc and manganese. They represent essential components of antioxidant enzymes or transport proteins which participate in intermediation of antioxidant reactions of ceruloplasmin, SOD, GSPx, and catalase. Both deficiency, and in some cases also excess of mentioned trace elements may contribute to oxidative stress. (Tab. 3, Fig. 3, Ref. 27.)
In order to study the effect of Chinese traditional medicine, "Bone Growth Fluid", on bone formation in bone lengthening, the limb lengthening model was made on goat to observe bone formation in the distracted area, and the content of the trace elements was determined. The bone-lengthening operation was carried out on the upper metaphysis of left tibia. The animals were divided into two groups following operation. From 2nd day afteroperation, "Bone Growth Fluid", 10 ml per kilogram body weight, was given daily to goats in the experimental group, and same amount of normal saline was given to goats in another group as control. The results showed-that new bone formation and bone remodeling in the experimental group appeared earlier than that in the control group, and the content of the trace elements was also improved. So Chinese Traditional medicine, "Bone Growth Fluid", could accelerate the accumulation of the trace elements in callus on the distracted sites and it might play some role in the promotion of osteogenesis and bone remodeling in bone lengthening.
The physiological and pharmacobiological changes associated with space flight are of greater concern. Exposure to a weightless environment has been shown to have numerous effects on body composition and organ functions. Alterations include decreases in muscle and liver mass, changes in bone structure and integrity, and changes in cardiovascular functions. Zero-gravity in particular has been reported to inhibit several physiological processes of bone formation, retard bone growth and impair the mechanical properties of bones. This report examines the effect of 14 days of spaceflight on the bone trace element compositions of rapidly growing rats. Marked changes of bone trace element contents were found in either weight-bearing bones or non-weight-bearing bones, depending on the metal species. Histological examination revealed an irregular thickening of the endosteal surface of the cortical bone (thoracic vertebrae) of the in-flight rat, whereas it was uniform in the ground control. We suggest that the microgravity environment causes several bone alternations, such as abnormal trace element compositions and defects in vertebral maturation.
Trace element analysis of human skeletal remains is an important tool in paleonutritional studies, providing unique information on 1) diachronic shifts and synchronous dietary differentiations within populations, as well as 2) paleodemographic variables, particularly the age of weaning. However, the initial expectations have not been fully met, the last 15 years' continued research has rather been characterized by a growing awareness of basic intricacies of the method. Firstly, postmortem changes in bone chemistry may lead to misinterpretations. Moreover, the theoretical basis for these interpretations is not as solid as it should to warrant unequivocal results. The main features of these diagenetic and interpretative problems are discussed in the present paper, followed by an evaluation of the potential applications of the technique.
In a postmortem study of 8 uremic patients (mean age 63.0), the concentration of 23 trace elements was determined in heart tissue with neutron activation analysis. The concentration was significantly increased in 10 elements - e.g. Co (p less than 0.001), As, Br, Ce, La, Sb, Sc (p less than 0.01), Fe, K and P (p less than 0.05) - compared to a control group of non-uremic individuals. As some of these elements are cardiotoxic, the results support our opinion that an excess of certain trace elements, cobalt in particular, may be etiological agents of importance in uremic heart failure.
Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of major and trace element concentrations in scalp hair samples from a population group (N = 1091) of Rio de Janeiro city. From these results, preliminary 'normal' or reference intervals were calculated which are for several trace elements (e.g. B, V, Co, Ge, Mo, Au, As, Se, Sb, Th), but also for some minor elements (e.g. Ca, Mg) in disaccord with data published by five clinical laboratories which used inductively coupled plasma atomic emission spectrometry (ICP-AES). The limitations of ICP-AES in routine hair analysis is shown by comparison of detection limits for both methods and by results from two laboratory intercomparison exercises. It is evident from these data that published reference intervals have to be used with extreme caution and that their urgent revision, based on reliable data produced by the ICP-MS technique, is of extreme importance.
The mean contents of trace elements in anterior gray horn section of cervical spinal cords of six amyotrophic lateral sclerosis (ALS) cases were relatively determined against those of six control cases by alpha-particle excited X-ray fluorescence analysis. The anterior gray horn section of cervical spinal cord samples were excited by 1.6 MeV alpha-particle beam of 2 mm diameter accelerated with a Van de Graaff accelerator, and characteristic X-ray spectra were measured with alpha Si(Li) detector. From the peak area on the X-ray spectra, the relative mean contents of the trace elements in cervical spinal cords of ALS and control cases were determined. As a result, the X-ray peaks of Al, Si, P, S, Cl, K, Ca, Ti, V, Mn, Fe, Cu and Zn were detected. The contents of Al, Si, P, Ca, Ti, V, Mn and Fe in ALS cases were higher than those in control cases. The contents of S, Cl, K, Cu and Zn in ALS and control cases were equal to each other within standard deviation. The precipitation mechanisms of Al, Si, P, Ca, Ti, V, Mn and Fe into cervical spinal cord of ALS cases are discussed on the basis of the previous studies.
Although protein-energy malnutrition occurs commonly in patients with end-stage renal disease undergoing maintenance dialysis treatment, it is not the only form of malnutrition that may exist in these individuals. They may also suffer from deficiencies of micronutrients, particularly trace elements and vitamins. More commonly occurring vitamin deficiencies in maintenance dialysis patients include those for vitamin C (ascorbate), folate, vitamin B6 (pyridoxine), and 1,25-dihydroxycholecalciferol (calcitriol). Among trace elements, deficiencies may occur more commonly for iron, zinc, and possibly selenium, whereas toxicities are more common with aluminum and possibly copper. Evidence suggests that there is an abnormally high prevalence of antioxidant deficiency in maintenance dialysis patients, especially because a low intake of protein and energy may be associated with inadequate ingestion of antioxidant vitamins (ie, vitamins E and C and carotenoids). Thus, some micronutrient deficiencies in maintenance dialysis patients may contribute to the development of atherosclerotic cardiovascular disease. Dietary requirements for vitamins and trace elements in maintenance dialysis patients are reviewed and the recommended daily intakes are discussed.
We examined leaf injuries and measured trace element concentrations in vascular plants from an urban ecosystem with distinct stress valences (the city of Palermo), and compared them with samples of the same species from sites where the stress potential is lower. Urban pollution influences macro-, micro- and toxic element concentrations in leaves. Therefore these leaves can be used as markers of the chemical and biological effects of atmospheric pollution. We studied the trace element content in the leaves of two species, oleander and oak, both fairly tolerant plants and good indicators and bio-monitors of pollution contaminants. Samples were collected at various sites in different periods.
The per-capita intakes of zinc, cadmium, copper and of chromium were estimated from food consumption data in 28 countries and were found to correlate directly with the age-corrected mortalities from cancers of intestine, prostate, breast, leukemia, skin and of other organs, suggesting that the anticarcinogenic effect of selenium is counteracted by other trace elements. Similarly calculated dietary intakes of manganese are inversely correlated, particularly with the mortalities from cancer of pancreas, an organ normally known to contain high concentrations of this element. Arsenic intakes correlate inversely with the male lung cancer mortalities. A number of other direct and inverse associations were observed which suggest that trace elements in the human diet may hav both benign and adverse effects on tumor development. The zinc concentrations in whole blood collected from healthy donors in the U.S. correlate directly with regional mortalities from cancers of intestine, breast and of other sites. The origin of these associations is discussed primarily in terms of the seleium-antagonistic effect of zinc and of some of the other elements considered. Results of animal experiments and of other studies are cited which support hypotheses that link human cancer development to possible deficiencies or excesses in the dietary trace element intakes.