Structural background for serological cross-reactivity between bacteria of different enterobacterial serotypes.

The structure of the oligosaccharide repeating units of endotoxins from Gram-negative bacteria is characteristic for the different serogroups and serotypes of bacteria. Detailed examination of the cross-reactions of three enterobacterial serotypes, Proteus morganii O34, Escherichia coli O111, and Salmonella enterica sv. Adelaide O35, was performed using sensitive tests (ELISA, immunoblotting).

Isolation and structure elucidation of anhydroluteins from cooked sorrel (Rumex rugosus Campd.).

Anhydrolutein I (= (all-E,3R,6'R)-3',4'-didehydro-beta,gamma-caroten-3-ol; 2) and anhydrolutein II (= (all-E, 3R,6'S)-2',3'-didehydro-beta,epsilon-caroten-3-ol; 3) have been isolated and characterized from the extract of steam-cooked sorrel. The presence of these compounds in cooked vegetable is postulated to be due to acid-catalyzed dehydration of lutein (1; Scheme). The structures of the isolated anhydroluteins were established by UV/VIS, CD, and 1H-NMR spectroscopy, and mass spectrometry.

In-solution and on-plate light-catalyzed E/Z isomerization of cyclic chalcone analogues. Lipophilicity of E- and Z-2-(X-benzylidene)-1-benzosuberones.

Some cyclic chalcone analogues [E-2-(X-benzylidene)-1-indanones, -tetralones, and -benzosuberones], on-plate UV light-catalyzed formation of new chromatographic spots, can be observed during thin-layer chromatography (TLC). Gas chromatographic (GC) analysis of selected derivatives indicates the formation of one new substance in each case. GC coupled with mass spectrometry and 1H NMR analysis of the samples reveals that the compounds formed are the respective Z-2-(X-benzylidene)-1-indanones, -tetralones, and -benzosuberones.

Synthesis and evaluation of the permeability transition inhibitory characteristics of paramagnetic and diamagnetic amiodarone derivatives.

Several amiodarone analogues were synthesized varying the 2-substituent on the benzofuran ring and diethylaminoethyl side chain of phenolether by introducing 2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrole and 1,2,5,6-tetrahydropyridine nitroxides or their amino or hydroxylamino precursors. The new compounds were screened on isolated mitochondria and perfused heart and their toxicity was evaluated on WRL-68 liver cells and H9C2 cardiomyocytes. Most of the newly synthesized derivatives exerted uncoupling effect on the mitochondrial oxidative phosphorilation at higher concentrations, compared to amiodarone and one of the modified amiodarone analogues showed an effect similar to that of amiodarone on the mitochondrial permeability transition and on restoring of mitochondrial high-energy phosphate metabolites in perfused hearts.

MS and NMR investigation of bioactive quinazolones.

To prepare effective PARP [poly(ADP)-ribose)polymerase-1] inhibitors, starting from 2-mercapto-4(3H)-quinazolone (1), several S-alkyl derivatives--2-alkylsulfanyl-3H-quinazolin-4-ones (2-5, 7-9)--as well as an S-benzyl derivative (10) were prepared using a simple alkylation method. Some of them are known compounds. Their structure was studied thoroughly by MS and NMR methods.

Epimerisation of lutein to 3'-epilutein in processed foods.

Lutein can convert to 3'-epilutein and anhydrolutein I in acidic medium as well as during different cooking methods. To our knowledge, this is the first demonstration of the epimerisation and dehydration of lutein in native samples. During different cooking processes the lutein content of the processed vegetables and fruits dramatically decreases, thus the bioavailability of processed plant food may also decrease.

Regulation of kinase cascades and transcription factors by a poly(ADP-ribose) polymerase-1 inhibitor, 4-hydroxyquinazoline, in lipopolysaccharide-induced inflammation in mice.

Activation of the nuclear enzyme poly(ADP-ribose) polymerase (PARP) is involved in numerous pathophysiological conditions. Because PARP-1 knockout mice are resistant to endotoxin-induced shock and inhibitors of the enzyme were reported to have similar beneficial properties, we investigated the effect of 4-hydroxyquinazoline (4-HQN), a potent PARP-1 inhibitor, on the modulation of kinase cascades and the regulation of transcription factors in a rodent septic shock model. T2-weighted magnetic resonance imaging showed the pattern of anatomical localization of the inflammatory response in bacterial lipopolysaccharide (LPS)-treated mice and the anti-inflammatory effect of the PARP-1 inhibitor.

Decrease of the inflammatory response and induction of the Akt/protein kinase B pathway by poly-(ADP-ribose) polymerase 1 inhibitor in endotoxin-induced septic shock.

The lack of efficacy of anti-inflammatory drugs, anti-coagulants, anti-oxidants, etc. in critically ill patients has shifted interest towards developing alternative treatments. Since inhibitors of the nuclear enzyme poly-(ADP-ribose) polymerase (PARP) were found to be beneficial in many pathophysiological conditions associated with oxidative stress and PARP-1 knock-out mice proved to be resistant to bacterial lipopolysaccharide (LPS)-induced septic shock, PARP inhibitors are candidates for such a role.

Convenient syntheses of symmetrical and unsymmetrical glycosyl carbodiimides and N,N-bis(glycosyl)cyanamides.

Reaction of glycosyl trimethylphosphinimides with carbon disulfide under mild conditions (room temperature, short reaction time) leads to symmetrical glycosyl carbodiimides. Addition of bis(trimethylsilyl)carbodiimide to peracetylated aldoses under the influence of SnCl(4) afforded N,N-bis(glycosyl)cyanamides for the first time. Readily accessible unsymmetrical N,N'-bis(glycosyl)thioureas can be desulfurated and transformed into the corresponding carbodiimides using HgO in CHCl(3)/water at room temperature.

BGP-15 - a novel poly(ADP-ribose) polymerase inhibitor - protects against nephrotoxicity of cisplatin without compromising its antitumor activity.

Nephrotoxicity is one of the major dose limiting side effects of cisplatin chemotherapy. The antitumor and toxic effects are mediated in part by different mechanisms, thus, permitting a selective inhibition of certain side effects. The influence of O-(3-piperidino-2-hydroxy-1-propyl)nicotinic amidoxime (BGP-15) - a poly(ADP-ribose) polymerase (PARP) inhibitor - on the nephrotoxicity and antitumor efficacy of cisplatin has been evaluated in experimental models.

Kinetic and crystallographic studies of glucopyranosylidene spirothiohydantoin binding to glycogen phosphorylase B.

Glucopyranosylidene spirothiohydantoin (TH) has been identified as a potential inhibitor of both muscle and liver glycogen phosphorylase b (GPb) and a (GPa) and shown to diminish liver GPa activity in vitro. Kinetic experiments reported here show that TH inhibits muscle GPb competitively with respect to both substrates phosphate (K(i)=2.3 microM) and glycogen (K(i)=2.