Polycationic star polymers with hyperbranched cores for gene delivery

Core-shell type stars synthesized via atom transfer radical polymerization were used for the delivery of nucleic acids. The interior of the stars consisted of hyperbranched poly(arylene oxindole), while the arms were composed of poly(N,N-dimethylaminoethyl methacrylate). The length of the star arms varied in degree of polymerization (DP) from 14 to 98. The hydrodynamic radius of the structures measured in water indicated the presence of small aggregates, while isolated stars ranging in size from 14 to 29 nm were seen in organic solvent. The phase transition temperatures of the stars in water, measured in basic conditions, were shifted to lower values with increasing DP of the arms. Stable polyplexes of stars with plasmid DNA were formed. Their size varied from 300 nm to 400 nm, depending upon the DP of arms. The zeta potential of the polyplexes was positive, which facilitated their cellular uptake. The DP of the arms influenced the transfection efficiency of HT-1080 cells, demonstrating that stars are promising candidates for synthetic gene vectors.     

Effect of elevated accumulation of iron in ferritin on the antioxidants content in soybean sprouts

Cultivation of soybean sprouts in abiotic stress conditions, resulted from the presence of 5–25?mM FeSO₄ in the culture media, causes a strong overexpression of ferritin. Accumulation of ferritin iron in sprouted seeds germinated in the 20?mM solution of FeSO₄ was 67 times higher than in sprouts germinated in distilled water. The cultivation conditions also influence on another antioxidant content—mainly β-carotene content, which increased 28 times (in sprouts cultured in 10?mM FeSO₄ solution) in comparison to the content in dry seeds. Obtained in stress conditions sprouted seeds contain less tocochromanoles than raw seeds. However, their total tocochromanol content was higher than in sprouted seeds cultured in distilled water in every examined concentration of Fe²⁺. A total antioxidant activity is increased only during culturing in 0–10?mM media, and it is positively correlated to the total phenolic compounds content (r?=?0.8498). We concluded that germination in high abiotic stress also causes the increase in different antioxidants content, not only in ferritin, which is directly involved in the process of iron detoxification.     

New design of electric double layer capacitors with aqueous LiOH electrolyte as alternative to capacitor with KOH solution

Activated carbon (AC) fiber cloths and a hydrophobic microporous polypropylene (PP) membrane, both modified with lithiated acetone oligomers, were used as electrodes and a separator in electric double layer capacitors (EDLCs) with aqueous lithium hydroxide (LiOH) as the electrolyte. Electrochemical characteristics of EDLCs were investigated by cyclic voltammetry (CV), galvanostatic charge-discharge cycle tests and impedance spectroscopy (EIS), compared with a case of the capacitor with aqueous potassium hydroxide (KOH) as an electrolyte. As a result, the capacitor with LiOH aqueous solution and a modified separator and electrodes was found to exhibit higher specific capacitance, maximum energy stored and maximum power than that with KOH aqueous solution.     

The impact of glycated pea proteins on bacterial adhesion

Adhesion is one of the bacterial strategies indispensable for colonization of the small intestine. Food components reaching the small intestine, are not only digested and absorbed there, but may also influence the microorganisms colonizing the mentioned region. In this way, nutrients, particularly the ones the enzymatic degradation of which is hindered, acquire the ability to modify the adhesive potential of the autochthonic microorganisms. The glycated food proteins are noteworthy here for they often undergo relevant structural and functional alterations. Such proteins tend to display a lowered susceptibility to enzymatic degradation and thus may act as modulators of both metabolic activity and adhesive potential of bacteria adhered to the intestinal cells. For that reason, this study aimed at establishing the impact of the glycated pea proteins on adhesion of the bacteria from the genera: Lactobacillus, Enterococcus, and Escherichia, which are typical for the human small intestine.     

Cross sections for ionization of K, L and M shells of atoms by impact of electrons and positrons with energies up to 1 GeV: Analytical formulas

Analytical formulas are presented for the easy calculation of cross sections for ionization of K, L and M shells of neutral atoms by impact of electrons and positrons with kinetic energies up to 1 GeV. Each formula contains a number of parameters that are characteristic of the element, the active electron shell and the projectile particle. The values of these parameters were determined by fitting the cross section values in an extensive database that was calculated recently by means of a composite algorithm that combines the distorted-wave and plane-wave Born approximations. Tables of parameter values are given for all elements, from hydrogen (Z=1) to einsteinium (Z=99). The proposed analytical expressions yield ionization cross sections that agree with those in the numerical database to within about 1%, except for projectiles with near-threshold energies.