Fate and transport of radiocesium, radiostrontium and radiocobalt on urban building materials.

Kinetics of (137)Cs, (60)Co and (85)Sr sorption on powdered building materials in aqueous suspensions at 20 °C for interaction times of 1, 7, 14 and 28 days were studied. The (137)Cs distribution coefficient (Kd) values for all building materials except limestone practically did not change during 28 days of sorption. The Kd ((85)Sr) was several orders of magnitude lower than for (60)Co. The highest values were observed for asphalt and granite. An effective method to study the radionuclide distribution in depth of building materials using layer-by-layer sanding was developed. Using the developed method, the (137)Cs, (60)Co and (85)Sr distribution with depth of selected building materials at different air humidity, time and temperature was studied. Relative humidity (RH) was found to influence significantly the (85)Sr depth distribution in the case of granite (unlike (137)Cs and (60)Co). While (85)Sr penetrated to 0.5 mm in depth of granite at RH 30%, at RH 87% the depth of (85)Sr penetration to granite reached up to 7 mm.

T-cadherin loss induces an invasive phenotype in human keratinocytes and squamous cell carcinoma (SCC) cells in vitro and is associated with malignant transformation of cutaneous SCC in vivo.

BACKGROUND: Cadherins play important roles in controlling keratinocyte growth, differentiation and survival. Atypical glycosylphosphatidylinositol-anchored T-cadherin (T-cad) is highly expressed in the basal keratinocyte layer of skin. The role of T-cad in keratinocyte biology and pathology is unclear. OBJECTIVES: To define the role of T-cad in the pathogenesis of cutaneous squamous cell carcinoma (SCC) through gain-of-function and loss-of-function studies in vitro and through examination of T-cad expression patterns in human cutaneous SCC specimens in relation to histological classification of degree of tumour differentiation. METHODS: In vitro studies employed lentiviral-mediated overexpression/silencing of T-cad in normal human keratinocyte (HaCaT) and SCC (A431) cell lines, monolayer and multicellular spheroid culture models, cell morphology analyses and assays of random motility and invasion. Immunohistochemistry was performed on skin specimens from patients with actinic keratosis, Bowen disease or SCC. RESULTS: In vitro, silencing of T-cad induced a morphologically elongated and disorganized cell phenotype, increased random motility and markedly enhanced invasive potential. Overexpression of T-cad induced a morphologically spread and compact cell phenotype and blunted invasive potential. In vivo, regional loss of T-cad expression was more frequent and prominent in SCC classified as moderately-to-poorly differentiated than in SCC classified as well differentiated. However, in both categories aberrant and/or absence of T-cad expression was associated with histological features of a potentially more malignant and invasive phenotype of cutaneous SCC. CONCLUSIONS: T-cad is a controlling determinant of SCC phenotype and invasive behaviour and its loss is associated with the process of malignant transformation from noninvasive to invasive SCC.

[Effect of an increased level of natural radioactivity on the glycogen content of peripheral blood leukocytes in Microtus oeconomus Pall]. / Vliianie povyshennogo urovniia estestvennoi radioaktivnosti na soderzhanie glikogena v leikotsitakh perifericheskoi krovi polevok-ekonomok (Microtus oeconomus Pall.).

In experiments on Microtus oeconomus Pall., living in natural conditions with normal (0.72-1.08 pA/kg) and increased (3.6-1440 pA/kg) levels of external gamma-irradiation and affected by numerous incorporated radionuclides, the differences were detected, by the cytochemical method, both in the total glycogen content of leucocytes and in the type of grouping of cells depending on the degree of their saturation with polysaccharide.

[Effect of increased natural radioactivity on bone marrow morphology of Microtus oeconomus pall]. / Vliianie povyshennoi estestvennoi radioaktivnosti v srede obitaniia na morfologiiu kostnogo mozga u Microtus oeconomus pall.

It was established that Microtus oeconomus Pall. living in territories with the increased radiation background exhibit focal myeloid hyperplasia in the bone marrow, changes in the maturation indices of erythroid and myeloid elements, increase in number of karyocytes due to the increase in their mitotic activity. It is suggested that activation of vole haemopoiesis is an adaptive reaction of the organism to the effect of the radioecological factor.