Monolayers of the HSA dimer on polymeric microparticles-electrokinetic characteristics.

Human serum albumin dimer (dHSA) enhances the accumulation and retention of anti-tumor drugs. In this work, monolayers of dHSA on polystyrene microparticles were prepared and thoroughly characterized. The changes in the electrophoretic mobility of microparticles upon the addition of controlled amounts of dHSA were measured using Laser Doppler Velocimetry (LDV) technique.

New 3'-O-aromatic acyl-5-fluoro-2'-deoxyuridine derivatives as potential anticancer agents.

New aromatic and aliphatic 3'-O-acyl-5-fluoro-2'-deoxyuridine derivatives were synthesized and evaluated as candidates for prodrugs against various cancer cell lines. As the most promising candidate for antimalignant therapeutics was found a dual-acting acyl derivative 7h, which apparently released not only the known anticancer nucleoside, 5-fluoro-2'-deoxyuridine (FdU), but also an additional active metabolite, acetylsalicylic acid, reinforcing thus therapeutic effect of FdU. Promising therapeutic indices showed also some aromatic dicarboxylic acids derivatives decorated with FdU esters (11 and 12).

Electrokinetic characteristics of HSA dimer and its monolayers at mica.

Human serum albumin (HSA) dimer was synthesized in a reaction of the monomer with 1,6-bis(maleimido)hexane (BMH) cross-linker. Thorough physicochemical characteristics of the dimer were performed. They comprised the diffusion coefficient, hydrodynamic diameter, electrophoretic mobility as a function of pH, isoelectric point and electrokinetic charge.

Revealing deposition mechanism of colloid particles on human serum albumin monolayers.

Colloid particle deposition was applied in order to characterize human serum albumin (HSA) monolayers on mica adsorbed under diffusion transport at pH 3.5. The surface concentration of HSA was determined by a direct AFM imaging of single molecules.

Recombinant albumin adsorption on mica studied by AFM and streaming potential measurements.

Recombinant human serum albumin (rHSA) in monomeric state is widely used in pharmaceutical industry as a drug excipient and for preparing coatings for medical devices. In this work the adsorption process of rHSA on model mica surface at pH 3.5 was studied using the atomic force microscopy (AFM) and in situ streaming potential measurements.

Recombinant albumin monolayers on latex particles.

The adsorption of recombinant human serum albumin (rHSA) on negatively charged polystyrene latex micro-particles was studied at pH 3.5 and the NaCl concentration range of 10(-3) to 0.15 M.

KfrA plasmid protein monolayers on latex particles-electrokinetic measurements.

Monolayers of KfrA, a protein assisting in bacteria plasmid segregation, on polystyrene latex particles were produced in controlled self-assembling under diffusion-controlled conditions. The coverage of the protein was quantitatively determined as a function of ionic strength (up to 0.15 M, NaCl) via micro-electrophoretic measurements and concentration depletion with the aid of AFM imaging.

Revealing properties of the KfrA plasmid protein via combined DLS, AFM and electrokinetic measurements.

Physicochemical characteristics of the plasmid KfrA protein in electrolyte solutions were done using a combination of dynamic light scattering (DLS), atomic force microscopy (AFM) and electrokinetic methods. The size of the protein was determined via the diffusion coefficient measurements using DLS. It was revealed from these measurements that the protein exists in an aggregated state composed of four molecules.

Mechanism of HSA adsorption on mica determined by streaming potential, AFM and XPS measurements.

Adsorption of human serum albumin (HSA) on mica at pH 3.5 (0.15M NaCl) was studied using in situ streaming potential measurements, AFM imaging and XPS.

Altered expression and activities of enzymes involved in thiamine diphosphate biosynthesis in Saccharomyces cerevisiae under oxidative and osmotic stress.

Thiamine diphosphate (TDP) serves as a cofactor for enzymes engaged in pivotal carbohydrate metabolic pathways, which are known to be modulated under stress conditions to ensure the cell survival. Recent reports have proven a protective role of thiamine (vitamin B(1)) in the response of plants to abiotic stress. This work aimed at verifying a hypothesis that also baker's yeast, which can synthesize thiamine de novo similarly to plants and bacteria, adjust thiamine metabolism to adverse environmental conditions.

The upregulation of thiamine (vitamin B1) biosynthesis in Arabidopsis thaliana seedlings under salt and osmotic stress conditions is mediated by abscisic acid at the early stages of this stress response.

Background: Recent reports suggest that vitamin B1 (thiamine) participates in the processes underlying plant adaptations to certain types of abiotic and biotic stress, mainly oxidative stress. Most of the genes coding for enzymes involved in thiamine biosynthesis in Arabidopsis thaliana have been identified. In our present study, we examined the expression of thiamine biosynthetic genes, of genes encoding thiamine diphosphate-dependent enzymes and the levels of thiamine compounds during the early (sensing) and late (adaptation) responses of Arabidopsis seedlings to oxidative, salinity and osmotic stress.

Enzymes that control the thiamine diphosphate pool in plant tissues. Properties of thiamine pyrophosphokinase and thiamine-(di)phosphate phosphatase purified from Zea mays seedlings.

The pool of thiamine diphosphate (TDP), available for TDP-dependent enzymes involved in the major carbohydrate metabolic pathways, is controlled by two enzyme systems that act in the opposite directions. The thiamine pyrophosphokinase (TPK) activates thiamine into TDP and the numerous phosphatases perform the reverse two-step dephosphorylation of TDP to thiamine monophosphate (TMP) and then to free thiamine. Properties and a possible cooperation of those enzymes in higher plants have not been extensively studied.