Danuta Smutnicka

Metabolic profiles of exudates from chronic leg ulcerations.

&NA; Chronic leg ulceration is a disease usually associated with other comorbidities, and significantly reduces patient quality of life. Infected leg ulcers can lead to limb‐threatening sequelae or mortality. Leg ulcerations are colonized by a number of microbes that are able to cause life‐threating infections in susceptible patients. Wound exudate is a body fluid that collects metabolites from patient eukaryotic cells and from prokaryotic bacterial communities inhabiting the wound. This study aimed at identification of metabolites in exudates collected from chronic leg ulcers, and correlation of this metabolome with patient comorbidities and microbiological status of the wound. By means of NMR spectroscopy we detected 42 metabolites of microbial or patient origin. The metabolites that were in abundance in exudates analyzed were lactate, lysine, and leucine. Metabolites were associated with the presence of neutrophils in wounds and destruction of high quantities of microbes, but also with hypoxia typical for venous insufficiency. The combination of nuclear magnetic resonance spectroscopy technique and partial least squares discriminant analysis allowed us to further discriminate groups of metabolites with regards to potential clinical meaning. For example, to discriminate between S.aureus versus all other isolated microbial species, or between patients suffering from type I or II diabetes versus patients without diabetes. Therefore, wound exudate seems to be highly applicable material for discriminant analysis performed with the use of NMR technique to provide for rapid metabolomics of chronic wound status. HighlightsNMR technique is highly applicable for evaluation of processes taking place within a wound.The wound exudate is a very useful material for these analyses.Wound exudate metabolites might be used as biomarkers of wound status.

A comparison of an antibacterial sandwich dressing vs dressing containing silver.

The purpose of this study was to compare the efficacy of dressings containing octenidine vs. dressings containing silver in the wound healing in the course of a chronic venous disease. There were two groups of 40 patients who met the inclusion criteria and who did not meet the exclusion criteria. The patients were randomly assigned into the groups (envelope method). The first, “O group” was treated with octenidine‐based dressings. The second, “S group” was treated with silver dressings. The study lasted for 56 days. All patients in the research were treated with medical compression stockings with cotton understockings. Microbiological eradication was observed on the 28th day of the study among 33% of patients in the treatment group vs. 6% in control group. On the 56th day of the treatment, these percentages equalled 72% and 35%. The rate of healing was faster in the 0 group than in the S group. In the wounds <10 cm2 it was faster by 1.35 cm2/week and in wounds >10 cm2 it equalled 3.44 cm2. The reduction of pain level was 37.5% higher in the O group, in contrast with the S group. One change of a dressing in the O group led to a 0.06 cm2 greater wound size reduction and in the case of wounds >10 cm2 to 0.29 cm2 reduction compared with the S group. The presented results indicate that the efficacy of dressings containing octenidine is higher compared to silver dressings.

Bad to the Bone: On In Vitro and Ex Vivo Microbial Biofilm Ability to Directly Destroy Colonized Bone Surfaces without Participation of Host Immunity or Osteoclastogenesis.

Bone infections are a significant public health burden associated with morbidity and mortality in patients. Microbial biofilm pathogens are the causative agents in chronic osteomyelitis. Research on the pathogenesis of osteomyelitis has focused on indirect bone destruction by host immune cells and cytokines secondary to microbial insult. Direct bone resorption by biofilm pathogens has not yet been seriously considered. In this study, common osteomyelitis pathogens (Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Streptococcus mutans) were grown as biofilms in multiple in vitro and ex vivo experiments to analyze quantitative and qualitative aspects of bone destruction during infection. Pathogens were grown as single or mixed species biofilms on the following substrates: hydroxyapatite, rat jawbone, or polystyrene wells, and in various media. Biofilm growth was evaluated by scanning electron microscopy and pH levels were monitored over time. Histomorphologic and quantitative effects of biofilms on tested substrates were analyzed by microcomputed tomography and quantitative cultures. All tested biofilms demonstrated significant damage to bone. Scanning electron microscopy indicated that all strains formed mature biofilms within 7 days on all substrate surfaces regardless of media. Experimental conditions impacted pH levels, although this had no impact on biofilm growth or bone destruction. Presence of biofilm led to bone dissolution with a decrease of total volume by 20.17±2.93% upon microcomputed tomography analysis, which was statistically significant as compared to controls (p <0.05, ANOVA). Quantitative cultures indicated that media and substrate did not impact biofilm formation (Kruskall-Wallis test, post-hoc Dunne’s test; p <0.05). Overall, these results indicate that biofilms associated with osteomyelitis have the ability to directly resorb bone. These findings should lead to a more complete understanding of the etiopathogenesis of osteomyelitis, where direct bone resorption by biofilm is considered in addition to the well-known osteoclastic and host cell destruction of bone.

Wpływ sieci większej (omentum majus) na redukcję biofilmu bakteryjnego z implantów wprowadzonych do jam brzusznych szczurów laboratoryjnych

Biofilm-related infections are considered 60–80% of all nosocomial infections. High biofilm tolerance of such antimicrobials towards antiseptics and antibiotics is the reason why new therapeutic approaches are developed. In the present study, the analysis of the pedunculated omentum majus’s, ability to eradicate Staphylococcus aureus and Klebsiella pneumoniae biofilm from abdominal cavity of laboratory Wistar rats was performed. The pedunculated omentum majus was treated as a prototypic autogenic internal dressing. Obtained results indicate that the omentum majus possesses an ability to sequestrate but not to kill ana-