A novel role for factor VIII and thrombin/PAR1 in regulating hematopoiesis and its interplay with the bone structure.

Analysis of hematopoietic stem cells (HSCs) in factor VIII knockout (FVIIIKO) mice revealed a novel regulatory role for the coagulation cascade in hematopoiesis. Thus, HSCs in FVIIIKO mice had reduced proportions of CD34(low) cells within Lin(-)Sca(+)Kit(+) progenitors, and exhibited reduced long-term repopulating capacity as well as hyper granulocyte-colony-stimulating factor (G-CSF)-induced mobilization. This disregulation of HSCs is likely caused by reduced levels of thrombin, and is associated with altered protease-activated receptor 1 (PAR1) signaling, as PAR1 KO mice also exhibited enhanced G-CSF-induced mobilization.

Deep-trap competition model for TL in alpha-Al2O3:C heating stage.

The present report deals with the experimental observations of the thermally stimulated migration of charge carriers from trapping centres responsible for the main thermoluminescence (TL) peak at 450 K to a deep trap and, also, the optically stimulated transport of carriers from the deep trap to the main trap, which gives rise to the phototransferred TL at 450 K, in anion-defective alpha-Al2O3 crystals. The obtained results provide an experimental proof to the adequacy of the assumptions made in the model of the mutual interaction of the main and deep traps in the crystals under study.

Thermoluminescent and dosimetric properties of anion-defective alpha-Al2O3 single crystals with filled deep traps.

Some new experimental results illustrating the effect of deep traps on luminescent and dosimetric properties of anion-defective single crystals of alpha-Al2O3 have been described. It was found that deep traps had an electronic origin. They were filled thanks to the photoionisation of F-centres and their filling was accompanied by the conversion of F-->F+ centres.

Thermoluminescent dosemeters based on TLD-500 detectors for control of neutron fields.

The results of a study dealing with detection of neutrons in thermoluminescent (TL) photon radiation detectors, type TLD-500, based on an anion-defective corundum have been reported. The detection method uses the transformation of neutron radiation into gamma radiation arising when neutrons are captured by cadmium nuclei. A comparative analysis of the data obtained with the TL detectors and results of radiometric measurements suggested applicability of this method.

[Microbiological synthesis and transformation of prostaglandins].

The review surveys current literature on microbiological synthesis and modification of prostaglandins. Three possible approaches to the use of microorganisms for prostaglandin production are considered including synthesis de novo, arachidonic acid transformation, and prostaglandin modifications. The most typical reactions of prostaglandin transformations by microorganisms are analysed: hydrolysis, hydroxylation, reduction and beta-oxidation.