A Novel In Vitro Method to Assess the Microbial Barrier Function of Tissue Adhesives Using Bioluminescence Imaging Technique.

Background. Tissue glues can minimize treatment invasiveness, mitigate the risk of infection, and reduce surgery time; ergo, they have been developed and used in surgical procedures as wound closure devices beside sutures, staples, and metallic grafts. Regardless of their structure or function, tissue glues should show an acceptable microbial barrier function before being used in humans. This study proposes a novel in vitro method using Escherichia coli Lux and bioluminescence imaging technique to assess the microbial barrier function of tissue glues. Different volumes and concentrations of E. coli Lux were applied to precured or cured polyurethane-based tissue glue placed on agar plates. Plates were cultured for 1 h, 24 h, 48 h, and 72 h with bioluminescence signal measurement subsequently. Herein, protocol established a volume of 5 µL of a 1 : 100 dilution of E. coli Lux containing around 2 × 107 CFU/mL as optimal for testing polyurethane-based tissue glue. Measurement of OD600nm, determination of CFU/mL, and correlation with the bioluminescence measurement in p/s unit resulted in a good correlation between CFU/mL and p/s and demonstrated good reproducibility of our method. In addition, this in vitro method could show that the tested polyurethane-based tissue glue can provide a reasonable barrier against the microbial penetration and act as a bacterial barrier for up to 48 h with no penetration and up to 72 h with a low level of penetration through the material. Overall, we have established a novel, sensitive, and reproducible in vitro method using the bioluminescence imaging technique for testing the microbial barrier function of new tissue glues.

Effects of asparaginases and L-carnitine on Western-diet-induced hepatosteatosis in mice.

Background: Asparaginases are common chemotherapeutic agents used for the treatment of acute lymphoblastic leukemia as a single or combinational therapy. Accompanying hepatotoxicity makes its use in elderly patients with pre-conditions, as obesity or other hepatopathies, difficult. Various hepatoprotective compounds like, L-carnitine, are discussed to ameliorate the induced hepatotoxicity. Methods: Here we aimed to establish a mouse model to study the effect of asparaginases (L-asparaginase and Oncaspar) and L-carnitine on Western-diet-induced hepatosteatosis in mice. Dose-escalation studies were performed to analyze asparaginases induced hepatotoxicity in C57BL/6 mice with normal or fatty livers. Subsequently, the effect of L-carnitine to improve the induced toxicity was tested. Results: Our results showed mild-to-moderate hepatotoxic effects while the Western-diet induced a higher degree of vacuolization and hepatocyte damage in liver tissue. Testing of L-carnitine in the established models did not show any protective effect on the toxicity or impairment of the efficacy of asparaginases. Conclusion: The here established models were able to demonstrate the asparaginase-induced hepatotoxic effects which were enhanced by the Western-diet. However, to test potential ameliorating drugs, the models might need some improvements.