Effects of topical application of taurolidine on second intention healing of experimentally induced wounds in rats

Does taurolidine have any effect on liver regeneration and oxidation in the experimental hepatectomy model?

Objective: Taurolidine is a bicyclic molecule produced by the natural amino acid taurine. Antibacterial, antiendotoxic and cytoprotective effects of taurolidine have been shown experimentally. Data on the effects of taurolidine on oxidative stress and hepatic regeneration are limited. The aim of the study was to evaluate the effect of taurolidine on hepatic regeneration and oxidative stress in rats undergoing partial hepatectomy.

Material and Methods: Forty adult, male Wistar Albino rats were randomly divided into four equal groups: sham (S) group (n= 10), post-sham opera- tion taurolidine administered (ST) group (n= 10), partial hepatectomy (H) group (n= 10) and post-partial hepatectomy taurolidine administered (HT) group (n= 10). 100 mg/kg/day taurolidine was administered for seven days. Blood and liver tissue samples were collected on postoperative day seven. Liver tissue malondialdehyde, glutathione and Cu-Zn superoxide dismutase activity (SOD) were measured to assess oxidative stress. Binuclear hepato- cyte and Ki-67 antigen levels were measured to evaluate hepatic regeneration.

Results: There was no difference between the groups for malondialdehyde, Cu-Zn superoxide dismutase and glutathione levels (p> 0.05). Binuclear nuclei levels were comparable between the H and HT groups (p= 0.06), while taurolidine decreased binuclear hepatocyte levels in the sham operated groups (p= 0.02). Taurolidine application decreased Ki-67 levels after partial hepatectomy (p= 0.001).

Conclusion: Taurolidine may cause anti-regenerative effects after partial hepatectomy without causing oxidative damage.

Does antibiotic use accelerate or retard cutaneous repair? A systematic review in animal models

Background

The presence of infections is one of the main factors that leads to delays in healing or non-closure of cutaneous wounds. Although the goal of antibiotic use is to treat or prevent infection, there is currently no agreement on the effectiveness of these products.

Aim

The aim of this study was to evaluate the efficacy of antibiotic use during the healing process of skin wounds in animal models not intentionally infected, as well as to analyze the advances and limitations of the studies carried out in this field.

Main methods

This systematic review was performed according to the PRISMA guidelines, using a structured search on the MedLine (PubMed) and Scopus platforms to retrieve studies published until August 29, 2018, 13:35p.m. The studies included were limited to those that used excision or incision wound models and that were not intentionally infected. The data for the animal models, antibiotic used, and the main results of the studies were extracted, and compared where possible. Bias analysis and methodological quality assessments were examined through the SYRCLE’s Risk of Bias tool.

Key findings

Twenty-seven studies were selected. Overall, the effects of the antibiotic on the wound decreased inflammatory cell infiltration and promoted an increased number of fibroblasts, extracellular matrix constituents, re-epithelialization and tissue strength. A great deal of important information about the methodology was not presented, such as: the statistical analysis used, the animal model (sex and age), antibiotic dosage, blinding and randomization of the animals chosen.

Significance

Based on the results found, we believe that antibiotic therapy can be considered a viable alternative for the treatment of cutaneous wounds. However, current evidence obtained from the methodological quality analysis points towards a high risk of bias. This is due to the incomplete characterization of the experimental design and treatment protocol, which compromises the reproducibility of the studies.

Efficiency of Emulsified Particle-Associated Polyhexamethylenbiguanid-Hydrochlorid (Polihexanide) for Peritoneal Lavage in a Murine Sepsis Model

BACKGROUND

Peritoneal lavage is often used for peritonitis, however, the volume and type of lavage fluid varies. Saline or Ringer's solution are used most often and lavage is performed until the fluid is clear. However, at present there is no irrigation fluid for peritoneal lavage with residual antiseptic activity. Because the combination of aqueous polyhexamethylenbiguanid-hydrochlorid (PHMB) and egg phosphatidylcholine containing oil/water emulsions (Lipofundin^® MCT 20%, B. Braun AG, Melsungen, Germany) protect mammalian cells without neutralizing the antiseptic effect of PHMB, it seemed promising to investigate such human cell protecting, yet antibacterial combination for peritoneal lavage in a murine sepsis model.

METHODS

After induction of colon ascendens stent peritonitis (CASP) in mice, the foci were eradicated by re-laparotomy, followed by twofold lavage with 2 × 3 mL of the tested emulsion. The following lavage fluids were investigated blindly: 10% Lipofundin/0.05% PHMB, 100% Lipofundin, 0.05% PHMB, and 0.9% saline. After 24 hours the animals were euthanized and organs, blood, and lavage fluid were examined for cytokine levels (tumor necrosis factor [TNF]-α, interferon [IFN]-γ, interleukin [IL]-6, IL-10), liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], gamma-glutamyltransferase [gamma-GT], glutamate dehydrogenase [GLDH]), creatinine, and bacterial density.

RESULTS

Only the combination of Lipofundin/PHMB (n = 23) increased the survival rate. Compared with saline alone, PHMB alone decreased the survival rate. Twenty-four hours after induction of peritonitis, the lowest number of colony forming units (CFU) was observed after lavage with PHMB/Lipofundin in all examined organs, blood, and lavage fluid (p < 0.01). Alanine aminotransferase, AST, and creatinine levels were increased after lavage with PHMB compared with the other lavage fluids (p < 0.05).

CONCLUSIONS

Peritoneal lavage using 0.05% aqueous PHMB alone resulted in no survival benefit in a CASP murine model. The increase of liver enzymes and creatinine seem to be a toxic side effect of PHMB. However, an emulsion of 0.05% PHMB/10% Lipofundin decreased cytotoxicity while maintaining antiseptic efficiency. The advantage for survival was explained by decrease of bacterial load in organs, blood, and lavage fluid. The results provide a new option for the treatment of peritonitis using peritoneal lavage with the combination of PHMB/Lipofundin.

Consensus on Wound Antisepsis: Update 2018

Wound antisepsis has undergone a renaissance due to the introduction of highly effective wound-compatible antimicrobial agents and the spread of multidrug-resistant organisms (MDROs). However, a strict indication must be set for the application of these agents. An infected or critically colonized wound must be treated antiseptically. In addition, systemic antibiotic therapy is required in case the infection spreads. If applied preventively, the Wounds-at-Risk Score allows an assessment of the risk for infection and thus appropriateness of the indication. The content of this updated consensus recommendation still largely consists of discussing properties of octenidine dihydrochloride (OCT), polihexanide, and iodophores. The evaluations of hypochlorite, taurolidine, and silver ions have been updated. For critically colonized and infected chronic wounds as well as for burns, polihexanide is classified as the active agent of choice. The combination 0.1% OCT/phenoxyethanol (PE) solution is suitable for acute, contaminated, and traumatic wounds, including MRSA-colonized wounds due to its deep action. For chronic wounds, preparations with 0.05% OCT are preferable. For bite, stab/puncture, and gunshot wounds, polyvinylpyrrolidone (PVP)-iodine is the first choice, while polihexanide and hypochlorite are superior to PVP-iodine for the treatment of contaminated acute and chronic wounds. For the decolonization of wounds colonized or infected with MDROs, the combination of OCT/PE is preferred. For peritoneal rinsing or rinsing of other cavities with a lack of drainage potential as well as the risk of central nervous system exposure, hypochlorite is the superior active agent. Silver-sulfadiazine is classified as dispensable, while dyes, organic mercury compounds, and hydrogen peroxide alone are classified as obsolete. As promising prospects, acetic acid, the combination of negative pressure wound therapy with the instillation of antiseptics (NPWTi), and cold atmospheric plasma are also subjects of this assessment.