The antimicrobial activity of cetylpyridinium chloride (CPC) and miramistin (MST) solutions at different concentrations (5¾10 "5 to 0.4 %) and a dressing, containing 0.15 % CPC, were tested against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli after 30 (solutions) and 60 min (fleece) incubation, respectively. Furthermore, the cytotoxic effects of CPC and MST were examined in human keratinocyte (HaCaT) and murine fibroblast (L929) cell lines. A dose of 3¾10 "3 % CPC or MST was sufficient to entirely eradicate S. aureus after 30 min incubation. To achieve the same effect, higher concentrations were required against E. coli (0.025 % CPC; 0.0125 % MST) and P. aeruginosa (0.5 % CPC; 0.05 % MST). The CPC-fleece showed a high antiseptic effect against all three bacterial strains, although it did not completely eliminate P. aeruginosa. Both substances showed a high cytotoxic impact at higher tested concentrations (CPC .3¾10 "3 %; MST .8¾10 "4 %). CPC showed high antimicrobial potency at low concentrations against S. aureus, accompanied by low cytotoxic (side) effects at these concentrations, whilst the required minimal concentration to eradicate E. coli and P. aeruginosa was shown to be cytotoxic for keratinocytes and fibroblasts. The necessary antibacterial amounts of MST were lower, but also cytotoxic in direct contact with typical human wound cells. With regard to demographic changes and increasing bacterial resistance, new effective antiseptics, such as CPC and MST, incorporated in wound dressings without releasing an active substance could help to improve the treatment and healing rates of chronic wounds.

In this study, polyaminopropyl biguanide (PAPB) was compared to the molecularly closely related polyhexamethylene biguanide (PHMB) with respect to chemical relationship, antiseptic efficacy and cytotoxicity in vitro. Cytotoxicity for human keratinocytes (HaCaTs) and murine fibroblasts (L929) was determined according to ISO EN 10993-5 for both substances. Antimicrobial efficacy tests were performed via determination of the MBC, quantitative suspension method for substances and investigation of two PAPB-or PHMB-containing dressings against Staphyloccoccus aureus, Escherichia coli and Pseudomonas aeruginosa, according to international standards. Prior mass spectrometry was performed for chemical differentiation of the investigated substances. PHMB showed high toxicity even in low concentrations for both tested cell lines and a high antimicrobial efficacy against S. aureus and E. coli. In the case of PAPB, no or only low cytotoxicity was detected after 72 h, whilst comparable antibacterial features are lacking, as PAPB showed no relevant antimicrobial effects. Even though chemically closely related, PAPB proved to be ineffective in bacterial eradication, whilst PHMB showed a high efficacy. The discovery and establishment of safe and effective alternative antiseptics are important issues for the treatment of infected wounds. In particular, rising bacterial resistances to established agents, as well as ongoing discussions of potential toxic or carcinogenic effects emphasize this necessity. Nevertheless, the presented results highlight that even small changes in the chemical structure of related agents such as PHMB and PAPB can dramatically affect their efficacy and, therefore, need to be carefully distinguished and assessed side by side.

Certain combinations of B vitamins demonstrate a positive influence on human keratinocytes and fibroblasts. Vitamins especially promoted fibroblast migration, and a statistically significant induction of keratinocyte proliferation was observed. Therefore, local vitamin application could benefit the physiologic wound healing process.

BackgroundControl of translation allows for rapid adaptation of the cell to stimuli, rather than the slower transcriptional control. We presume that translational control is an essential process in the control of adipogenesis, especially in the first hours after hormonal stimulation. 3T3-L1 preadipocytes were cultured to confluency and adipogenesis was induced by standard protocols using a hormonal cocktail. Cells were harvested before and 6 hours after hormonal induction. mRNAs attached to ribosomes (polysomal mRNAs) were separated from unbound mRNAs by velocity sedimentation. Pools of polysomal and unbound mRNA fractions were analyzed by microarray analysis. Changes in relative abundance in unbound and polysomal mRNA pools were calculated to detect putative changes in translational activity. Changes of expression levels of selected genes were verified by qPCR and Western blotting.ResultsWe identified 43 genes that shifted towards the polysomal fraction (up-regulated) and 2 genes that shifted towards free mRNA fraction (down-regulated). Interestingly, we found Ghrelin to be down-regulated. Up-regulated genes comprise factors that are nucleic acid binding (eIF4B, HSF1, IRF6, MYC, POLR2a, RPL18, RPL27a, RPL6, RPL7a, RPS18, RPSa, TSC22d3), form part of ribosomes (RPL18, RPL27a, RPL6, RPL7a, RPS18, RPSa), act on the regulation of translation (eIF4B) or transcription (HSF1, IRF6, MYC, TSC22d3). Others act as chaperones (BAG3, HSPA8, HSP90ab1) or in other metabolic or signals transducing processes.ConclusionsWe conclude that a moderate reorganisation of the functionality of the ribosomal machinery and translational activity are very important steps for growth and gene expression control in the initial phase of adipogenesis.

BackgroundDue to demographical changes the number of elderly patients depending on oral anticoagulation is expected to rise. Prolonged bleeding times in case of traumatic injuries represent the drawback of these medications, not only in major trauma, but also in superficial wounds. Therefore, dressings capable of accelerating coagulation onset and shortening bleeding times are desirable for these patients.MethodsThe hemostatic potential and physical properties of different types of superficial wound dressings (standard wound pad, two alginates, chitosan, collagen (Lyostypt®), oxidized cellulose, and QuikClot®) were assessed in vitro. For this purpose the clotting times of blood under the influence of the named hemostatics from healthy volunteers were compared with Marcumar® or ASS® treated patients. For that, a newly developed coagulation assay based on spectrophotometric extinction measurements of thrombin activity was used.ResultsThe fastest coagulation onset was observed for oxidized cellulose (Ø 2.47 min), Lantor alginate-l (Ø 2.50 min) and QuikClot® (Ø 3.01 min). Chitosan (Ø 5.32 min) and the collagen Lyostypt® (Ø 7.59 min) induced clotting comparatively late. Regarding physical parameters, QuikClot® showed the lowest absorption capacity and speed while chitosan and both alginates achieved the highest. While oxidized cellulose displayed the best clotting times, unfortunately it also revealed low absorption capacity.ConclusionsAll tested specimens seem to induce clotting independently from the administered type of oral anticoagulant, providing the possibility to neglect the disadvantage in clotting times arising from anticoagulation on a local basis. QuikClot®, oxidized cellulose and unexpectedly alginate-l were superior to chitosan and Lyostypt®. Due to its additional well-known positive effect on wound healing alginate-l should be considered for further investigations.