High-Titre Neutralizing Antibodies to H1N1 Influenza Virus after Mouse Immunization with Yeast Expressed H1 Antigen: A Promising Influenza Vaccine Candidate.

H1N1 influenza virus is still regarded as a serious pandemic threat. The most effective method of protection against influenza virus and the way to reduce the risk of epidemic or pandemic spread is vaccination. Influenza vaccine manufactured in a traditional way, though well developed, has some drawbacks and limitations which have stimulated interest in developing alternative approaches.

Highly sensitive electrochemical biosensor based on redox - active monolayer for detection of anti-hemagglutinin antibodies against swine-origin influenza virus H1N1 in sera of vaccinated mice.

Background: In this work, we report an electrochemical biosensor for the detection of anti-hemagglutinin antibodies against the swine virus H1N1 present in mice sera immunized with mixture of His-H1 HA in monomeric and oligomeric form. The oriented immobilization of the recombinant His-tagged hemagglutinin (His-H1 HA) consists of: (i) formation of a mixed layer of 4-mercaptobutanol (MBT) and the thiol derivative of dipyrromethene (DPM); (ii) complexation of Cu (II) by DPM; (iii) immobilization of His-H1 HA via coordination bonds between Cu (II) sites from DPM-Cu (II) complex and imidazole nitrogen atoms of a histidine tag; (iv) filling free spaces with bovine serum albumin. The interactions between recombinant His- H1 HA covalently attached to the electrode surface and the anti-hemagglutinin H1 antibodies present in mice sera were explored with Osteryoung square-wave voltammetry.

Modeling of Dolichol Mass Spectra Isotopic Envelopes as a Tool to Monitor Isoprenoid Biosynthesis.

The cooperation of the mevalonate (MVA) and methylerythritol phosphate (MEP) pathways, operating in parallel in plants to generate isoprenoid precursors, has been studied extensively. Elucidation of the isoprenoid metabolic pathways is indispensable for the rational design of plant and microbial systems for the production of industrially valuable terpenoids. Here, we describe a new method, based on numerical modeling of mass spectra of metabolically labeled dolichols (Dols), designed to quantitatively follow the cooperation of MVA and MEP reprogrammed upon osmotic stress (sorbitol treatment) in Arabidopsis ().

An avian influenza H5N1 virus vaccine candidate based on the extracellular domain produced in yeast system as subviral particles protects chickens from lethal challenge.

Highly pathogenic avian influenza is an on-going problem in poultry and a potential human pandemic threat. Pandemics occur suddenly and vaccine production must be fast and effective to be of value in controlling the spread of the virus. In this study we evaluated the potential of a recombinant protein from the extracellular domain of an H5 hemagglutinin protein produced in a yeast expression system to act as an effective vaccine.

The anti-sigma factor RsrA responds to oxidative stress by reburying its hydrophobic core.

Redox-regulated effector systems that counteract oxidative stress are essential for all forms of life. Here we uncover a new paradigm for sensing oxidative stress centred on the hydrophobic core of a sensor protein. RsrA is an archetypal zinc-binding anti-sigma factor that responds to disulfide stress in the cytoplasm of Actinobacteria.

Impact of calcium binding and thionylation of S100A1 protein on its nuclear magnetic resonance-derived structure and backbone dynamics.

S100 proteins play a crucial role in multiple important biological processes in vertebrate organisms acting predominantly as calcium signal transmitters. S100A1 is a typical representative of this family of proteins. After four Ca(2+) ions bind, it undergoes a dramatic conformational change, resulting in exposure, in each of its two identical subunits, a large hydrophobic cleft that binds to target proteins.

[Assesment of energy and basic components intake in selected group of the breastfeeding women].

Background: Breastfeeding is considered the most beneficial, natural nutrition for babies. Qualitative and quantitative composition of breast milk is ideal for implementing all the nutritional needs of infants up to 6 months of age, assuming that the nursing mother's diet is correct.

Objective: The aim of the study was to evaluate the intake of energy, proteins, fat, carbohydrates and cholesterol in the group of 100 breastfeeding women, aged 19 to 38 years, from Masovian province.

[Assessment of stimulant use especially caffeine intake in selected group of the breastfeeding women].

Background: Taking into account the negative impact of stimulants, including alcohol, nicotine and excessive consumption of caffeine on the baby and his mother, a very important is to stop or to restrict their use, especially during pregnancy and lactation.

Objective: Purpose of the study was to evaluate alcohol consumption, cigarette smoking, tobacco smoke exposure and caffeine consumption in breastfeeding women from Masovian Province.

Material And Method: The survey was conducted from September 2010 till March 2011.

The doping effect of fluorinated aromatic solvents on the rate of ruthenium-catalysed olefin metathesis.

A study concerning the effect of using a fluorinated aromatic solvent as the medium for olefin metathesis reactions catalysed by ruthenium complexes bearing N-heterocyclic carbene ligands is presented. The use of fluorinated aromatic hydrocarbons (FAH) as solvents for olefin metathesis reactions catalysed by standard commercially available ruthenium pre-catalysts allows substantially higher yields of the desired products to be obtained, especially in the case of demanding polyfunctional molecules, including natural and biologically active compounds. Interactions between the FAH and the second-generation ruthenium catalysts, which apparently improve the efficiency of the olefin metathesis transformation, have been studied by X-ray structure analysis and computations, as well as by carrying out a number of metathesis experiments.

Assignment of the zinc ligands in RsrA, a redox-sensing ZAS protein from Streptomyces coelicolor.

ZAS proteins are widespread bacterial zinc-containing anti-sigma factors that regulate the activity of sigma factors in response to diverse cues. One of the best characterized ZAS proteins is RsrA from Streptomyces coelicolor, which responds to disulfide stress. Zn-RsrA binds and represses the transcriptional activity of sigmaR in the reducing environment of the cytoplasm but undergoes reversible, intramolecular disulfide bond formation during oxidative stress.

Stability of the residual structure in unfolded BPTI in different conditions of temperature and solvent composition measured by disulphide kinetics and double mutant cycle analysis.

The folding funnel model proposes a clear description of the protein folding process. To test this model, additional data on the structures populated in different stages of folding and their influence on further folding are required. Here, we use the double mutant strategy and disulphide formation kinetics measurements to study the impact on folding of the residual structure in unfolded bovine pancreatic trypsin inhibitor (BPTI).

Fluorescence and NMR studies of intramolecular stacking of mRNA cap-analogues.

Intramolecular stacking of a series of new synthesized dinucleotide mRNA cap analogues has been investigated in aqueous buffers by means of fluorescence and 1H-NMR at various pH and temperatures, and compared with that for 7-methylguanosine(5')ppp(5')guanosine (m7GpppG), as well as its hypermethylated derivative m(3)2,2,7GpppG. Thermodynamic parameters for intramolecular self-association stabilized by stacking were established by temperature-dependent fluorescence quenching, taking into account collisional deactivation of the excited states. Relative orientations of the stacked bases in the cap analogues were determined with the aid of a program GEOSHIFT (Stolarski et al.

The effects of blocking the Na-Ca exchange at intervals throughout the physiological contraction-relaxation cycle of single cardiac myocyte.

The method of rapid superfusion of the single isolated ventricular myocytes of guinea-pig heart was used in order to inhibit the Na-Ca exchange throughout the physiological contraction-relaxation cycle. Superfusion of the cell at selected intervals during the contraction with the Na,Ca-free solution resulted in increase in its amplitude, increase in time to peak shortening and in delay of relaxation, albeit the cells relaxed before reperfusion of normal Tyrode solution. The largest increase in amplitude of contraction (to 134 +/- 16%) was observed when the effective exchange of the cell's environment was attained approximately 50 ms after the pulse stimulating contraction.

The effect of menadione on sarcoplasmic reticulum Ca2+ and contractions of single guinea-pig cardiomyocytes.

We investigated the effect of 2-methyl-1,4-naphtoquinone (Menadione) on sarcoplasmic reticulum (SR) Ca2+ content and electrically stimulated contractions (ESCs) of single isolated myocytes of guinea-pig ventricular myocardium. The contractures initiated by means of microinjections of caffeine into the close vicinity of the cell were used as an indirect index of the SR Ca2+ content. Superfusion of the cells for 45 min with Menadione resulted in gradual disappearance of contractile responses to caffeine, prolongation of time to peak amplitude of ESCs by 48 +/- 15% and complete inhibition of postrest and postextrasystolic potentiation.

Net Ca2+ influx and sarcoplasmic reticulum Ca2+ uptake in resting single myocytes of the rat heart: comparison with guinea-pig.

We tested Shattock and Bers' (1989) hypothesis according to which in rat cardiac myocytes net Ca2+ influx during diastole via Na/Ca exchange provides the main route of entry of Ca2+ available for activation of contractions. We used injections of caffeine into the close vicinity of the single, isolated rat or guinea-pig ventricular myocytes in order to release Ca2+ from sarcoplasmic reticulum (SR). The cells responded to caffeine with a transient contracture, the amplitude of which was regarded as a relative index of SR Ca2+ content.

[Two types of electromechanical coupling in myocardial myocytes].

Sarcoplasmic reticulum (SR) of isolated myocytes of guineapigs deprived of Ca2+ by means of short exposure of the cell to caffeine does not re-uptake Ca in the quiescent cell. In rat Ca2+ SR content is promptly recovered under the same experimental conditions. The results of this study confirm the two types of excitation-contraction coupling in isolated myocyes of gineapig and rat hearts: without Ca uptake and with Ca uptake between excitations, respectively.

[A map for recording of 15 precordial leads improves the sensitivity of the exercise test].

Authors analyzed ecg recordings of 112 exercise tests performed in males aged 29-62. 15 precordial leads map (inclusive of V1-V6 standard leads) was used to record ecg tracings. In 22 patients (19.

Excitation- and rest-dependent shifts of Ca in guinea-pig ventricular myocardium.

The rest- and excitation-dependent shifts of Ca and 45Ca in the isolated, perfused ventricles of guinea-pig hearts were investigated. As much as 50% of the total Ca content (2.2 mmol/kg ww) found in the ventricular muscle stimulated at a steady rate of 60/min, was released into perfusate during 4 min of rest.

Inotropic and electrophysiological effects of AB--2, a new antiarrhythmic agent, on isolated cardiac preparations.

Effects of AB--2, a compound structurally related to quinidine, on the force of contraction and intracellular potentials were studied in isolated cardiac preparations obtained from guinea pigs, rabbits, cats and dogs. AB--2 in concentrations of 3 and 6 microM increased the force of contraction of both ventricular and atrial muscle. This effect was absent in reserpinized preparations.

A new approach to the direct measurement of tension within the outer layers of the left ventricular wall of the dog heart.

Tension was measured within the outer layers of the left ventricular wall of the dog heart with the strain-gauge force transducer coupled to the wall at diastole without the distortion of its geometry. The transducer still attached to the wall or its segments was calibrated with the passive forces and with the known active force on the isolated, beating heart. The differences between the readings of the transducer and the calibrating force did not exceed 20% and in most experiments they were much smaller.