The influence of porcine cathelicidins on neutrophils isolated from rabbits in the course of bone graft implantation

[EN] Antimicrobial peptides are important elements of host defence because of their direct antimicrobial activity and modulatory role in innate immune response. The purpose of the study was to determine whether porcine peptides PR-39, protegrins (PGs) and low molecular weight extract (LMWE) are able to influence the neutrophil response during bone graft implantation in rabbits. The study was conducted on 10 White New Zealand rabbits and neutrophil activity was assayed on the basis of elastase, myeloperoxidase, and alkaline phosphatase release as well as free radical generation. Our study showed that PR-39 and PGs inhibited enzyme release from neutrophils except for elastase, which is essential in the first phase of injury. Superoxide and nitric oxide generation under the influence of PR-39 and PGs were also decreased. Moreover, we found that unlike separated peptides PR-39 and PGs, LMWE acts proinflammatorily, intensifying the neutrophil secretory response and free radical generation. These results should be taken into account in treatment with natural antimicrobial peptides. The increased neutrophil responses in the first phase of inflammation during surgery may be useful in prevention of infection, but LMWE should not be used in conditions in which excessive neutrophil response is injurious.Wessely-szponder, J.; Szponder, T.; Bobowiec, R.; Smolira, A. (2013). The influence of porcine cathelicidins on neutrophils isolated from rabbits in the course of bone graft implantation. World Rabbit Science. 21(3):175-183. doi:10.4995/wrs.2013.1350.SWORD17518321

Mass-Spectrometric Investigations of Silver Clusters

We report results of experimental studies on the silver clusters formation in laser desorption and matrix assisted laser desorption. Time-of-flight mass spectrometer was used to control process itself. Firstly, we investigated dependence of silver salts of variety chemical nature on formation of silver clusters. The most prominent was usage of organic silver salts (silver trifluoroacetate and silver benzoate). The biggest species obtained was $Ag_{45}^{+}$ (silver benzoate). Secondly, we examined influence of organic matrix (2,5-dihydroxybenzoic acid) on formation efficiency of silver clusters in matrix assisted laser desorption. In all cases we observed increase of silver clusters size