Characterization of lipophilicity and antiproliferative activity of E-2-arylmethylene-1-tetralones and their heteroanalogues.

A molecular library based on E-2-arylmethylene-1-tetralone has been designed and synthesized. A reversed phase high performance liquid chromatographic (RP-HPLC) method has been developed and applied to separate them and to characterize their lipophilicity. The chromatographic method applied here was suitable to separate the structural (ortho and para) isomers of compounds and was sensitive enough to differentiate their lipophilicities. The measured (k') and computer calculated (CLOGP) lipophilicity values has been compared. Good linear correlation has been found in the case of these structurally related molecules. In vitro biological assay has been performed with Methylene blue dying to investigate the antiproliferative potency of the compounds synthesized in this work. The measured (k') and calculated (CLOGP) lipophilicities of the compounds were compared with the antiproliferative activities and an optimum value of lipophilicity has been found for these compounds.

Fast in vivo water quantification in rat brain oedema based on T(1) measurement at high magnetic field.

BACKGROUND: In vivo water content determination based on magnetic resonance (MR) method is of importance in clinical practice as well as in animal studies to follow up the treatment given in order to reduce brain oedema. The methods proposed in the literature so far are largely time consuming. The aim of this study was to find a fast in vivo water quantification method having real advantage for patients suffering from critical conditions. METHOD: Cold injury was applied to provoke brain oedema in fourteen rats. T(1) values of both the oedematous area and the contralateral normal cortex were determined by two independent methods 24 hours after the cold impact. First, from a series of images recorded by inversion recovery spin echo (IRSE) sequence and then by progressive saturation experiment performed by localised MR spectroscopy using stimulated echo acquisition mode (STEAM). To reduce the acquisition time, a two-element repetition time array was optimised for the STEAM experiment, whereas four inversion times were used for T(1) mapping. Both methods were validated against gel phantoms with known T(1) values. After the MR measurements the animals were sacrificed and the water contents of the regions of interest were determined by gravimetric wet-dry method. FINDINGS: The reciprocals of the in vivo measured T(1) values were correlated with the reciprocals of the brain water contents. STEAM experiment showed stronger correlation (r=0.96) than IRSE (r=0.93). In addition, STEAM provided more accurate T(1) values in the phantom study. Determination of brain water content based on T1 measurement does work also at high magnetic field. Determination of brain water content by Magnetic Resonance Spectroscopy is feasible within 2 minutes. INTERPRETATION: Using the presented fast method, water content can be determined within a couple of minutes in animal experiments as well as in the daily clinical practice.

In vivo water quantification in mouse brain at 9.4 Tesla in a vasogenic edema model.

The aim of our study was to establish a simple in vivo method for water quantification in vasogenic edema, and provide data on imaging of mouse brain at 9.4 Tesla. Apparent T1 and spin density values determined by MRI were found to strongly correlate with the gravimetric water content of mouse brain undergoing cold injury. Using a two-point calibration line between the spin density values for pure water and cortex of mouse brain, as well as the corresponding water contents in vivo, water could be quantified with satisfactory accuracy.

Synthesis of and a comparative study on the inhibition of muscle and liver glycogen phosphorylases by epimeric pairs of d-gluco- and d-xylopyranosylidene-spiro-(thio)hydantoins and N-(d-glucopyranosyl) amides.

D-Gluco- and D-xylopyranosylidene-spiro-hydantoins and -thiohydantoins were prepared from the parent sugars in a six-step, highly chemo-, regio-, and stereoselective procedure. In the key step of the syntheses C-(1-bromo-1-deoxy-beta-D-glycopyranosyl)formamides were reacted with cyanate ion to give spiro-hydantoins with a retained configuration at the anomeric center as the major products. On the other hand, thiocyanate ions gave spiro-thiohydantoins with an inverted anomeric carbon as the only products. On the basis of radical inhibition studies, a mechanistic rationale was proposed to explain this unique stereoselectivity and the formation of C-(1-hydroxy-beta-D-glycopyranosyl)formamides as byproducts. Enzyme assays with a and b forms of muscle and liver glycogen phosphorylases showed spiro-hydantoin 12 and spiro-thiohydantoin 14 to be the best and equipotent inhibitors with K(i) values in the low micromolar range. The study of epimeric pairs of D-gluco and D-xylo configurated spiro-hydantoins and N-(D-glucopyranosyl)amides corroborated the role of specific hydrogen bridges in binding the inhibitors to the enzyme.

Effect of poly(ADP-ribose) polymerase inhibitors on the ischemia-reperfusion-induced oxidative cell damage and mitochondrial metabolism in Langendorff heart perfusion system.

Ischemia-reperfusion induces reactive oxygen species (ROS) formation, and ROS lead to cardiac dysfunction, in part, via the activation of the nuclear poly(ADP-ribose) polymerase (PARP, called also PARS and ADP-RT). ROS and peroxynitrite induce single-strand DNA break formation and PARP activation, resulting in NAD(+) and ATP depletion, which can lead to cell death. Although protection of cardiac muscle by PARP inhibitors can be explained by their attenuating effect on NAD(+) and ATP depletion, there are data indicating that PARP inhibitors also protect mitochondria from oxidant-induced injury. Studying cardiac energy metabolism in Langendorff heart perfusion system by (31)P NMR, we found that PARP inhibitors (3-aminobenzamide, nicotinamide, BGP-15, and 4-hydroxyquinazoline) improved the recovery of high-energy phosphates (ATP, creatine phosphate) and accelerated the reutilization of inorganic phosphate formed during the ischemic period, showing that PARP inhibitors facilitate the faster and more complete recovery of the energy production. Furthermore, PARP inhibitors significantly decrease the ischemia-reperfusion-induced increase of lipid peroxidation, protein oxidation, single-strand DNA breaks, and the inactivation of respiratory complexes, which indicate a decreased mitochondrial ROS production in the reperfusion period. Surprisingly, PARP inhibitors, but not the chemically similar 3-aminobenzoic acid, prevented the H(2)O(2)-induced inactivation of cytochrome oxidase in isolated heart mitochondria, suggesting the presence of an additional mitochondrial target for PARP inhibitors. Therefore, PARP inhibitors, in addition to their important primary effect of decreasing the activity of nuclear PARP and decreasing NAD(+) and ATP consumption, reduce ischemia-reperfusion-induced endogenous ROS production and protect the respiratory complexes from ROS induced inactivation, providing an additional mechanism by which they can protect heart from oxidative damages.

Efficient inhibition of muscle and liver glycogen phosphorylases by a new glucopyranosylidene-spiro-thiohydantoin.

Reaction of C-(1-bromo-1-deoxy-beta-glucopyranosyl)formamide 2 with thiocyanate ions was the key step of a short synthesis of D-glucopyanosylidene-spiro-thiohydantoin 7 which proved to be a potent inhibitor of muscle and liver glycogen phosphorylases.

Characterization of enhancing factor (EF) prepared from spleen of mice immunized with tetanus toxoid.

In cultures of spleen cells from tetanus toxoid-primed mice a soluble, nonspecific material appeared, which enhanced antibody response in vivo. The active material was purified by gel filtration on Sephadex-G-150 and by affinity chromatography on Con-A lectin. According to the immunological and physiochemical investigation the active material does not contain carbohydrate and its molecular weight is in the 100 000 dalton range.

Adaptive processes in child and adolescent swimmers. Blood coagulation and viscosity.

Multifactorial studies were performed in child and adolescent swimmers in the early period of training and in a submaximum state of training in the year's racing period. Blood coagulation, viscosity, acidity, protein metabolism, muscle enzymes, ions, haematologic, cardiac and endocrine parameters have been investigated. In the early period of training, physical exercise resulted in fibrinolysis, and a decrease in the fibrinogen and prothrombin levels and the platelet count. The same exercise in fully-trained organisms failed to produce such changes. Data concerning acidity, protein metabolism, muscle enzymes, ions, haematologic, cardiac and endocrine parameters will be published in subsequent papers.

The effect of enhancing factor on the immunity of mice against tetanus.

Enhancing factor was prepared from spleens of mice primed and reinjected with tetanus toxoid. The culture supernatant was separated by gel chromatography on Sephadex G-150, the resulted fractions were ultrafiltered and their enhancing activity was tested in vivo. The 1st fraction separated by gel chromatography proved to be active.

Comparison of the shock-inducing effect of anti-mouse anti-thymocyte horse serum and normal horse serum. I. Experiments with three-week-old mice.

Sera administered intravenously to mice hypersensitized with normal horse serum and with horse serum of anti-lymphocytic activity, produce reactions that differ considerably in mice treated in different ways. The experiments of the authors indicate that the anaphylactogenic effect of ATS is substantially stronger than that or normal horse serum. The paper discusses the clinical and theoretical conclusions to be drawn from this phenomenon observed in the experiments.

Comparison of the shock-inducing effect of anti-mouse anti-thymocyte horse serum and normal horse serum. II. Tests with ten-day-old mice.

Studying the shock-inducing effect of ATS and NHS in young (10-day-old) mice weighing 10-11 g, the authors have found that normal serum proved to be a significantly stronger sensitizing agent. Such a difference in the shock-inducing effect of the two sera can no longer be observed in the course of challenge. The paper discusses the observed phenomenon, taking into account the data available on the ontogeny of the immune apparatus of the mice.

The sensitizing properties of anti-mouse anti-thymocyte horse serum.

The authors have compared the anaphylaxis due to active and passive sensitization of mice. In the case of active sensitizing, anti-mouse anti-thymocyte horse serum (ATS), and/or normal horse serum (NHS), whereas in the case of passive sensitizing, plasma, peripheral leukocytes, spleen cells and thymocytes of sensitized animals were used. Provocation of shock was carried out by intravenous administration of ATS or NHS. Irreversible anaphylaxis occurred in a significantly higher rate in the case of ATS than NHS sensitivity, produced either actively, or passively. Differences have been found also between the 4 investigated materials according to their passive transfer potency.

Further investigations about the passive transfer of sensitivity caused by anti-thymocyte serum.

Soluble materials were obtained from the spleens and thymuses removed from mice sensitized by anti-thymocyte serum or normal horse serum. These materials were administered to mice. In the mice thus treated, anaphylaxis was provoked by iv inoculation of serum. Irreversible shock did not occur. Reversible anaphylactoid symptoms occured among the animals treated with the supernatants of cells of sensitized animals, in case when these cells have been disrupted by osmotic shock.

Experiments for producing specific immunological tolerance by intrauterinely administered immunocompetent human cells.

As a consequence of living human leukocytes administered intrauterinely on the 16th day of pregnancy, it was not possible to study the litter since it fell victim to cannibalism immediately after delivery. After the administration of sonically disintegrate leukocyte antigen healthy newborns were dropped. Living human leukocytes administered before the age of 2 day to mice treated in this way, produced no GVH reaction ascertainable with loss of weight but a considerable number of deaths occurred in comparison to the control. Further possibilities of studying the anti-human anti-thymocyte serum by means of cell chimeras are discussed.

Experiments for the production of graft-versus-host reaction in adult and infantile mice by means of human immunocompetent cells.

By administering anti-mouse ATS five times to random-bred Swiss albino mice weighing 16-18 and 10-11 g respectively, the authors have tried to produce immunological depression of such a degree which would allow living human leukocytes to cause GVH reaction. On the basis of the results it may be stated that with the serum dosage and manner of treatment applied, the human graft was not able to act against the recipient organism and to produce differences in body weight.

Exeriments for the production of graft-versus-host reaction in newborn mice by means of human immunocompetent cells.

It was not possible to produce the wasting disease in newborn mice by administering human leukocytes in Hanks' solution, or suspended in m-ATS or h-ATS. The attempt of the authors to produce immunosuppression by the administration of m-ATS started at newborn age-as a result of which the human immunocompetent cells would have produced serious GVH reaction-resulted only in a trend of GVH. The authors used only body weight measuring for detecting the GVH reaction. More sensitive parameters will be employed in their experiments in progress.