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Abstract—: Human natriuretic peptides (NUPs) types A and C were shown have different effects on the growth of monospecies and binary biofilms of human skin commensal microorganisms Staphylococcus epidermidis and Staphylococcus aureus. The effect of natriuretic peptides depended on cultivation conditions: at 37°С growth of monospecies biofilms formed by S. epidermidis and S. aureus was stimulated and inhibited, respectively, resulting in changed values of the biofilm average thickness and biomass in presence of NUPs. At 33°С effects of NUPs reversed: growth of S. epidermidis monospecies biofilms was inhibited. In binary biofilms at 37°С, NUPs were able to increase the competitiveness of S. epidermidis against S. aureus. NUPs affected predominantly biofilms and, to a lesser degree, planktonic cultures. This phenomenon makes it possible to consider NUPs as the molecules able to regulate the interactions between the human organism and skin microbiota. [ABSTRACT FROM AUTHOR]

A facile and eco-friendly method was developed to prepare a microporous CuO@Ag0 core–shell with high catalytic and antibacterial activities. Scanning and transmission electron microscopy revealed a preponderance of nearly spherical 50 nm particles with slight structure compaction. Comparison of the hysteresis loops confirmed the structure compaction after AgNP incorporation, and a significant decrease of the specific surface area from 55.31 m2 g−1 for CuO to 8.03 m2 g−1 for CuO@Ag0 was noticed. A kinetic study of 4-nitrophenol (4-NP) reduction into 4-aminophenol (4-AP) with sodium borohydride revealed a first order reaction that produces total conversion in less than 18 minutes. CuO@Ag0 also exhibited appreciable antibacterial activity against Staphylococcus aureus. The antibacterial effects were found to strongly depend on the size, contact surface, morphology and chemical composition of the catalyst particles. The addition of Ag0-NPs produced more reactive oxygen species in the bacteria medium. These results open promising prospects for its potential applications as a low cost catalyst in wastewater treatment and antibacterial agent in cosmetics. [ABSTRACT FROM AUTHOR]

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New segmented polyurethane (PU) anionomers based on hydroxytelechelic polybutadiene were synthesized via an aqueous dispersion process. Incorporation of carboxylic groups was achieved using thioacids of different length. Surface properties were investigated by mean of water absorption analysis and static contact-angle measurements using water, diiodomethane, formamide and ethylene glycol. Blood compatibility of the PUs was evaluated by in vitro adhesion assays using 111In-radiolabeled platelet-rich plasma and [125I]fibrinogen. Morphology of the adhered platelets was examined by scanning electron microscopy (SEM). Results were compared to two biomedicalgrade PUs, namely Pellethane® and Tecoflex®. Insertion of carboxylic groups increased surface hydrophilicity and limited water uptake (<8% for an ion content of 5% by weight). Surface energy of all synthesized PUs was between 40 and 45 mJ/m2. Platelet adhesion and fibrinogen adsorption on the PU anionomer surfaces were affected as a function to the increase of graft length; thiopropionic was the most haemocompatible, followed by thiosuccinic and then thioglycolic acid. SEM analyses of all ionic PU samples exhibited low platelet adhesion to surfaces with no morphological modification. In conclusion, increased hydrophily, dynamic mobility and charge repulsion are synergistic key factors for enhanced haemocompatibility. [ABSTRACT FROM AUTHOR]

The adrenal gland of mammals contains high concentrations of peripheral-type benzodiazepine receptors (PBR) and diazepam-binding inhibitor (DBI), a polypeptide which acts as an endogenous ligand for PBR. The aim of the present study was to investigate the localization of DBI and PBR in the adrenal gland of the frog Rana ridibunda. Reverse transcription followed by polymerase chain reaction with specific primers for the frog DBI cDNA showed the presence of DBI mRNA in frog adrenal gland extracts. The cellular distribution of DBI and PBR was investigated using an antiserum against the octadecaneuropeptide DBI [33-50] (ODN) and antibodies against the 18-kDa isoquinoline binding protein subunit of PBR (IBP), respectively. ODN-like immunoreactivity was found in chromaffin cells and in Stilling's cells, but not in adrenocortical cells. IBP-like immunoreactivity was observed in chromaffin cells, in Stilling's cells and in a small proportion (11%) of steroid-secreting cells. The ODN- and IBP-immunoreactive materials were homogeneously distributed in the cytoplasm of chromaffin cells and concentrated at the periphery of large cytoplasmic vesicles in Stilling's cells. The proportion of ODN-positive Stilling's cells showed marked circannual variations with a maximum in July. Similarly, the proportion of IBP-positive Stilling's cells was 17 times higher in July than in December. These results indicate that, in the frog adrenal gland, DBI-related peptides and PBR are simultaneously expressed in chromaffin cells and Stilling's cells, suggesting that endogenous ligands for PBR may play a physiological role in the control of adrenal cell activity. [ABSTRACT FROM AUTHOR]