No abstract available

[en] The labile pool of zinc in representative soils of Thrace region was determined by the application of isotopic dilution principle under laboratory condition. The effect of pH of the extraction mixture on the labile pool was also included in this study and the following results were found: 1. The percent radioactivity of ⁶⁵Zn in the equilibrium solution generally increased by the effect of pH of the solution. The difference at pH 5 and 7 in most of the soils was significant, while the difference at pH 7 and 8 with one exception was remarkably similar in all soils. 2. Zinc labile pool values of the soils were not affected mostly by the pH of the extraction solution. However, the differences at pH 5 and 7 and also at pH 7 and 8 were remarkably similar in most of the soils. 3. These findings were in agreement with the results of some investigators. (author)

[en] Short communication. A summary of a DEA report submitted under the title ''Etude au moyen du Zinc Radioactif ⁶⁵Zn du comportement des chenilles d'Heliothis armigera hubner (Lepidoptera, Noctuidae) sur Tomate.'' Univ. de Droit d'Economie et des Sciences d'Aix-Marseille-III. Faculte des Sciences et Techniques de Saint-Jerome. INRA-MONTEAVET, Station de Zoologie

[en] The possibility of employing a ⁶⁵Zn source in the gallium experiment BEST-2 with the aim of constraining the region of allowed oscillation parameters is examined. The source activity required for the BEST-2 experiment is calculated, and the size of the source and its effect on the results of oscillation measurements are discussed along with the possibilities for producing such a source. Various schemes for implementing respective measurements are considered.

No abstract available

[en] The Western blotting technique was used for the detection of zinc-binding proteins. Proteins were separated electrophoretically on 15% polyacrylamide-sodium dodecyl sulfate minigels, the gels were soaked in a reduction buffer, and the proteins were transferred to nitrocellulose filters. Zinc-binding proteins were probed with radioactive zinc (⁶⁵Zn) and were detected by autoradiography. This technique allows the detection of as little as 20 to 100 pmol of zinc metalloproteins

[en] The subcellular distribution of zinc and its interaction with androgens has been examined in the benign and malignant human prostate. Endogenously, most of the zinc was associated with the nuclear fraction but signigicant concentrations were also found in the cytosol. Furthermore, the epithelium contained more zinc than that found in either the stroma or the intact gland. Zinc concentrations were lower in the subcellular fractions of the cancerous tissue when compared to hyperplastic specimens. In vitro uptake of zinc into prostatic homogenates was rapid and at equilibrium the binding was stable for both the 4degC and the 37degC incubations. At low zinc concentrations (<5mM) the uptake was higher in the nucleus, whereas at higher concentraions, the cancerous tissue exhibited a greater capacity for the metal which was predominantly retained by the cytosol. Our data suggest the presence of a saturable zinc retention mechanism in the nucleus. The zinc uptake was found to be independent of any added androgen. In contrast, the total androgen uptake by the prostate was significantly enhanced by the addition of zinc. This effect was not due to increases in the nuclear and cytosolic receptor binding since zinc inhibited the binding of the androgen to these receptors. (author)

[en] Time dependent distribution and half-life of Zinc-65 in various organs of Chub ''Leuciscus cephalus L. 1758 (Pisces: Cyprinidae)'' have been investigated. Investigations performed on organ and tissue level have showhUn that absorbtion of Zn-65 varies from organ to organ or from tissue to tissue. The total biological half-life of Zn-65 administered by injection has been found to be 116 days in the fish

[en] Zinc plays an important role in prostate functions. For this reason, in this study some rats have been nourished with foods containing different zinc levels and some tissue samples removed at different intervals of time from their prostate, testis, and seminal vesicle. The zinc contents of these samples have been determined using the isotopic dilution analysis technique applied with ⁶⁵Zn. In this way, the zinc contents of tissues varying between 0.02-4.50 μg Zn/g wet tissue could be determined with good precision. As a result, the zinc content of the prostate was found to be considerably high with respect to the zinc contents of the testis and the seminal vesicle. It is also interesting to note that a high zinc level in foods results in the accumulation of zinc in the prostate rather than in the testis and the seminal vesicle. The zinc content of the seminal vesicle decreases with a function of time passed from the beginning of the diet which contrasts with the case of prostate. It is also very remarkable that when the level of zinc in the body is low, the content of zinc in the testis is considerably higher. (author)

[en] Induction of apoptosis and micronucleus formation has been studied in a transformed human squamous cell carcinoma cell line (SCL-II) after exposure to the Auger electron emitter Zinc-65 and after external low-LET radiation. Exposure to non-radioactive Zn and unirradiated cells served as controls. Studies on the cellular uptake of ⁶⁵Zn²⁺ have been carried out in vitro and conventional dosimetric models have been applied to derive the absorbed radiation dose. Auger electrons, generated during decay of ⁶⁵Zn²⁺, are strong inducers of micronuclei as well as of apoptosis, in comparison to external low-LET irradiation. The relative biological effectiveness has been determined and was found to be in the range of 1.2-2.7 for the two investigated biological endpoints, depending on which mathematical model for describing the dose-effect curves was used. A non-uniform distribution of intracellular Zn²⁺ was observed, showing a strong signal in the perinuclear region. We conclude that separate radiation weighting factors for Auger electrons should be established depending on the nuclide and its ability to interact with the DNA (e.g. ⁶⁵Zn by Zinc-finger proteins)