Healing Wounds Efficiently with Biomimetic Soft Matter: Injectable Self-Healing Neutral Glycol Chitosan/Dibenzaldehyde-Terminated Poly(ethylene glycol) Hydrogel with Inherent Antibacterial Properties.

The high prevalence of acquiring skin wounds, along with the emergence of antibiotic-resistant strains that lead to infections, impose a threat to the physical, mental, and socioeconomic health of society. Among the wide array of wound dressings developed, hydrogels are regarded as a biomimetic soft matter of choice owing to their ability to provide a moist environment ideal for healing. Herein, neutral glycol chitosan (GC) was cross-linked via imine bonds with varying concentrations of dibenzaldehyde-terminated polyethylene glycol (DP) to give glycol chitosan/dibenzaldehyde-terminated polyethylene glycol hydrogels (GC/DP). These dynamic Schiff base linkages (absorption peak at 1638 cm-1) within the hydrogel structure endowed their ability to recover from damage as characterized by high-low strain exposure in continuous step strain rheology. Along with their good injectability and biodegradability, the hydrogels exhibited remarkable inhibition against E. coli, P. aeruginosa, and S. aureus. GC/DP hydrogels demonstrated high LC50 values in vivo using zebrafish embryos as a model system due to their relative biocompatibility and a remarkable 93.4 ± 0.88% wound contraction at 30-dpw against 49.1 ± 3.40% of the control. To the best of our knowledge, this is the first study that developed injectable glycol chitosan/dibenzaldehyde-terminated polyethylene glycol self-healing hydrogels for application in wound healing with intrinsic bacteriostatic properties against the three bacteria.

Acupuncture for a first episode of acute ischaemic stroke: an observer-blinded randomised controlled pilot study.

OBJECTIVE: To determine the required sample size for, and feasibility of, a RCT examining the effectiveness of early acupuncture for acute ischaemic stroke. METHODS: Thirty-eight patients aged 40-85 years with a first episode of acute ischaemic stroke presenting within 72 h of stroke onset were randomly assigned to receive manual acupuncture (MA group; n=20) plus standard care or standard care only (control group, n=18). The acupuncture treatment was provided daily for 2 weeks. The primary outcome was the change in the National Institutes of Health Stroke Scale (NIHSS) score between baseline and 4 weeks. Secondary outcomes included changes in the Fugl-Meyer assessment (FMA) and the functional independence measure scores between baseline and 4 weeks, and changes in NIHSS, Barthel Index and modified Rankin Scale scores at 12 weeks. RESULTS: Thirty-one patients completed the study (dropout rate=18%) and adverse effects were minimal. No significant differences were seen between groups in the improvements in NIHSS scores, although there tended to be a greater reduction in NIHSS score after 1 week in the MA group relative to the control group (p=0.066). The post-stroke motor activity at 4 weeks was associated with a significantly increased FMA score in the acupuncture group compared with the control group (p<0.05), but not supported by intergroup analysis. CONCLUSIONS: This pilot study indicates that acupuncture appears to be safe for patients in the acute stage of ischaemic stroke. A subsequent trial with a larger sample size (estimated at n=122) is required to confirm whether early acupuncture intervention contributes to earlier functional improvement and to assess the longer-term clinical efficacy of acupuncture. TRIAL REGISTRATION NUMBER: NCT02210988; Results.