Chitosan, a polysaccharide derived from chitin, has excellent wound healing properties, including intrinsic antimicrobial and hemostatic activities. This study investigated the effectiveness of chitosan dressing and compared it with that of regular gauze dressing in controlling clinically surgical bleeding wounds and profiled the community structure of the microbiota affected by these treatments. The dressings were evaluated based on biocompatibility, blood coagulation factors in rat, as well as antimicrobial and procoagulant activities, and the microbial phylogenetic profile in patients with abdominal surgical wounds. The chitosan dressing exhibited a uniformly fibrous morphology with a large surface area and good biocompatibility. Compared to regular gauze dressing, the chitosan dressing accelerated platelet aggregation, indicated by the lower ratio of prothrombin time and activated partial thromboplastin time, and had outstanding blood absorption ability. Adenosine triphosphate assay results revealed that the chitosan dressing inhibited bacterial growth up to 8 d post-surgery. Moreover, 16S rRNA-based sequencing revealed that the chitosan dressing effectively protected the wound from microbial infection and promoted the growth of probiotic microbes, thereby improving skin immunity and promoting wound healing. Our findings suggest that chitosan dressing is an effective antimicrobial and procoagulant and promotes wound repair by providing a suitable environment for beneficial microbiota.
There have been numerous recent advances in wound care management. Nevertheless, the assessment of hemostatic dressing is essential to enable surgeons and other physicians and healthcare professionals to make the correct decisions regarding the disposition of severe hemorrhage. Here, we investigated the relative efficacies of chitosan-based and conventional gauze dressings in a rat model of femoral artery hemorrhage and in patients with surgical wounds. Dressing effectiveness was evaluated based on hemostatic profiles, biocompatibility, antimicrobial activity, and blood factor responses in coagulation. Relative to standard gauze dressing, the chitosan fiber (CF) dressing treatment significantly shortened the time to hemostasis in injured rats. Moreover, the CF dressing significantly prolonged partial thromboplastin time, enhanced blood absorption, and reduced antithrombin production without altering the prothrombin ratio. Unlike regular gauze bandages, the CF dressing demonstrated remarkable antibacterial activity. The results of this study indicate the effectiveness of chitosan as a hemostatic dressing and elucidate its underlying mechanism. It is possible that chitosan surgical dressings could serve as first-line intervention in hospital emergency care for uncontrolled hemorrhage.
Excellent wound dressing is essential for effective wound repair and regeneration. However, natural polymeric skin substitutes often lack mechanical strength and hydrophilicity. One way to overcome this limitation is to use biodegradable polymers with high mechanical strength and low skin-irritation induction in wet environments. Bacterial cellulose (BC) is an attractive polymer for medical applications; unlike synthetic polymers, it is biodegradable and renewable and has a strong affinity for materials containing hydroxyl groups. Therefore, we conjugated it with resveratrol (RSV), which has a 4′-hydroxyl group and exhibits good biocompatibility and no cytotoxicity. We synthesized BC scaffolds with immobilized RSV and characterized the resulting BC/RSV scaffold with scanning electron microscopy and Fourier-transform infrared spectroscopy. We found that RSV was released from the BC in vitro after ~10 min, and immunofluorescence staining showed that BC was highly biocompatible and regenerated epithelia. Additionally, Masson’s trichrome staining showed that the scaffolds preserved the normal collagen-bundling pattern and induced re-epithelialization in defective rat epidermis. These results indicated that RSV-conjugated BC created a biocompatible environment for stem cell attachment and growth and promoted epithelial regeneration during wound healing.
The role of hyperbaric oxygen therapy (HBOT) in the treatment of acute ischemic stroke is controversial. This prospective study assessed the efficacy and safety of HBOT as adjuvant treatment on 46 acute ischemic stroke in patients who did not receive thrombolytic therapy. The HBOT group () received conventional medical treatment with 10 sessions of adjunctive HBOT within 3–5 days after stroke onset, while the control group () received the same treatment but without HBOT. Early (around two weeks after onset) and late (one month after onset) outcomes (National Institutes of Health Stroke Scale, NIHSS scores) and efficacy (changes of NIHSS scores) of HBOT were evaluated. The baseline clinical characteristics were similar in both groups. Both early and late outcomes of the HBOT group showed significant difference (). In the control group, there was only significant difference in early outcome (). For early efficacy, there was no difference when comparing changes of NIHSS scores between the two groups () but there was statistically significant difference when comparing changes of NIHSS scores at one month (). The HBOT used in this study may be effective for patients with acute ischemic stroke and is a safe and harmless adjunctive treatment.