Nanofiber micro-dispersed oxidized cellulose as a carrier for topical antimicrobials: first experience

Recent advances in 3D printed cellulose-based wound dressings: A review on in vitro and in vivo achievements

Chronic wounds, especially diabetic ulcers, pose a significant challenge in regenerative medicine. Cellulose derivatives offer remarkable wound management properties, such as effective absorption and retention of wound exudates, maintaining an optimal moisture environment crucial for successful chronic wound regeneration. However, conventional dressings have limited efficacy in managing and healing these types of skin lesions, driving scientists to explore innovative approaches. The emergence of 3D printing has enabled personalized dressings that meet individual patient needs, improving the healing process and patient comfort. Cellulose derivatives meet the demanding requirements for biocompatibility, printability, and biofabrication necessary for 3D printing of biologically active scaffolds. However, the potential applications of nanocellulose and cellulose derivative-based inks for wound regeneration remain largely unexplored. Thus, this review provides a comprehensive overview of recent advancements in cellulose-based inks for 3D printing of personalized wound dressings. The composition and biofabrication approaches of cellulose-based wound dressings are thoroughly discussed, including the functionalization with bioactive molecules and antibiotics for improved wound regeneration. Similarly, the in vitro and in vivo performance of these dressings is extensively examined. In summary, this review aims to highlight the exceptional advantages and diverse applications of 3D printed cellulose-based dressings in personalized wound care.

Achieving hemostasis in dermatology-Part II: Topical hemostatic agents

Bleeding is a common occurrence during any dermatologic surgery that disrupts blood vessels. The complications of excess bleeding can include delayed wound healing, hematoma formation, infection, dehiscence, and necrosis. In part one of this review, we discussed the pre-operative, intra-operative, and post-operative management of patients undergoing dermatologic surgery. In Part two, we discuss traditional and new topical hemostatic agents used to achieve hemostasis in dermatological procedures and surgery. We will evaluate the caustic and non-caustic hemostatic agents as well as hemostatic dressings. The mechanisms of action, side effect profile, and advantages and disadvantages of the topical hemostatic agents are provided. Sources for this article were found searching the English literature in PubMed for the time period 1940 to March 2012. A thorough bibliography search was also performed and key references examined.

Effect of low-dose gaseous ozone on pathogenic bacteria

Background

Treatment of chronically infected wounds is a challenge, and bacterial environmental contamination is a growing issue in infection control. Ozone may have a role in these situations. The objective of this study was to determine whether a low dose of gaseous ozone/oxygen mixture eliminates pathogenic bacteria cultivated in Petri dishes.

Methods

A pilot study with 6 bacterial strains was made using different concentrations of ozone in an ozone-oxygen mixture to determine a minimally effective dose that completely eliminated bacterial growth. The small and apparently bactericidal gaseous dose of 20 μg/mL ozone/oxygen (1:99) mixture, applied for 5min under atmospheric pressure was selected. In the 2^nd phase, eight bacterial strains with well characterized resistance patterns were evaluated in vitro using agar-blood in adapted Petri dishes (10⁵ bacteria/dish). The cultures were divided into 3 groups: 1- ozone-oxygen gaseous mixture containing 20 μg of O₃/mL for 5 min; 2- 100% oxygen for 5 min; 3- baseline: no gas was used.

Results

The selected ozone dose was applied to the following eight strains: Escherichia coli, oxacillin-resistant Staphylococcus aureus, oxacillin-susceptible Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis, extended-spectrum beta-lactamase-producing Klebsiella pneumoniae, carbapenem-resistant Acinetobacter baumannii, Acinetobacter baumannii susceptible only to carbapenems, and Pseudomonas aeruginosa susceptible to imipenem and meropenem. All isolates were completely inhibited by the ozone-oxygen mixture while growth occurred in the other 2 groups.

Conclusion

A single topical application by nebulization of a low ozone dose completely inhibited the growth of all potentially pathogenic bacterial strains with known resistance to antimicrobial agents.