Bioabsorbable Fibrillar Gauze Dressing Based on N-Carboxyethyl Chitosan Gelling Fibers for Fatal Hemorrhage Control.

Death from lethal hemorrhage remains a major problem in various emergency scenarios. There is a continuous interest in the development of absorbable hemostatic dressings that can control hemorrhage rapidly and can be left in the wound site without removal. In this study, we report a hemostatic gauze dressing based on N-carboxyethyl chitosan (CECS) gelling fibers. The CECS fibrillar gauze combines ultra-hydrophilic, cationic chemical property of the fiber components with the fluffy nonwoven material form, exhibiting good conformability for wound filling, high fluid uptaking capacity, and enhanced blood-concentrating effect. In a swine femoral artery injury model, the CECS fibrillar gauze achieves shorter time to hemostasis and less blood loss compared with commercially available hemostatic dressings. This chitosan gelling fiber gauze demonstrates comparable bioabsorbability to clinically used absorbable hemostat and thus may be applied to treat fatal hemorrhage both in emergency medical services and in internal surgical procedures.

Multilineage-differentiating stress-enduring cells alleviate atopic dermatitis-associated behaviors in mice.

BACKGROUND: Pruritus is a recurring, long-lasting skin disease with few effective treatments. Many patients have unsatisfactory responses to currently available antipruritic treatments, and effective therapeutics are urgently needed to relieve symptoms. A previous study reported that mesenchymal stem cell (MSC)-mediated immune regulation could be used to treat skin inflammatory diseases. Multilineage-differentiating stress-enduring (Muse) cells are a new type of pluripotent stem cell that may also have the potential to treat inflammatory skin diseases. METHODS: Muse cells were isolated from human bone marrow-derived MSCs (BMSCs) via the 8-h longterm trypsin incubation (LTT) method. Repeated use of 2,4-dinitrofluorobenzene (DNFB) induced atopic dermatitis (AD) in a mouse model. Immunofluorescence, behavior recording, and image analysis were used to evaluate the therapeutic effect of subcutaneous Muse cell injection. Real-time quantitative polymerase chain reaction (qPCR) was used to measure the expression of inflammatory factors. In vitro, wound healing and cell proliferation experiments were used to examine the effect of Muse cell supernatant on keratinocytes. RESULTS: Our results showed that subcutaneous injection of Muse cells after AD model induction significantly alleviated scratching behavior in mice. The evaluation of dermatitis and photos of damaged skin on the back of the neck revealed that Muse cells reduced dermatitis, playing an active role in healing the damaged skin. The activation of spinal glial cells and scratching behavior were also reduced by Muse cell injection. In addition, we also showed that the expression levels of the inflammatory factors interleukin (IL)-6, IL-17α, and IL-33 in both the spinal cord and skin were suppressed by Muse cells. Furthermore, Muse cells not only exerted anti-inflammatory effects on lipopolysaccharide (LPS)-induced human HaCat cells but also promoted wound healing and keratinocyte proliferation. CONCLUSIONS: In vivo, Muse cells could alleviate scratching symptoms, reduce epidermal inflammation, and promote wound healing. In vitro, Muse cells could also promote the migration and proliferation of keratinocytes. In summary, Muse cells may become a new therapeutic agent for the treatment of AD.