Jiaming Shao’s research while affiliated with Zhejiang University and other places

Angiogenesis is a prominent component during the highly regulated process of wound healing. The application of exogenous vascular endothelial growth factor (VEGF) has shown considerable potential in facilitating angiogenesis. However, its effectiveness is often curtailed due to chronic inflammation and severe oxidative stress in diabetic wounds. Herein, an inflammation‐responsive hydrogel incorporating Prussian blue nanoparticles (PBNPs) is designed to augment the angiogenic efficacy of VEGF. Specifically, the rapid release of PBNPs from the hydrogel under inflammatory conditions effectively alleviates the oxidative stress of the wound, therefore reprogramming the immune microenvironment to preserve the bioactivity of VEGF for enhanced angiogenesis. In vitro and in vivo studies reveal that the PBNPs and VEGF co‐loaded hydrogel is biocompatible and possesses effective anti‐inflammatory properties, thereby facilitating angiogenesis to accelerate the wound healing process in a type 2 diabetic mouse model.

On June 13, 2020, a liquefied petroleum gas tanker exploded in Wenling. Here, we describe the mass casualty emergency response to the explosion. We collected the medical records of 176 inpatients at 8 hospitals from Taizhou and Hangzhou. The 176 inpatients with blast injuries comprised 70 females and 106 males, with an average age of 45.48 ± 19.96 years, and more than half of the patients were farmers. They were transported to 6 hospitals distributed around the explosion site in Taizhou in the initial rescue period and were grouped according to their new injury severity score as having mild, moderate, severe, or extremely severe injuries. Most patients with severe and extremely severe injuries were admitted to a superior hospital post-secondary triage. 44 patients experienced primary blast injuries, 137 experienced secondary blast injuries, 37 experienced tertiary blast injuries, and 40 patients experienced quaternary blast injuries. Multiple blast injuries were suffered by 62 patients. Most patients (95.45%) suffered external injuries, with the chest, extremities, and face as the main affected areas. Burns were diagnosed in 26 adults, of which 15.38%, 19.23%, 7.70%, and 57.69% suffered mild, moderate, severe, and extremely severe cases. 16 burn patients suffered from burn-blast injuries. Upper limbs and the head/face/neck area, as exposed areas, were more likely to experience a burn injury. Inhalation was the main accompanying injury. Of the 8 patients who died in the prehospital session, 7 had burn injuries. This report on the accident and injury characteristics of an open-air LPG-related explosion will facilitate responses to subsequent catastrophes.

[This corrects the article DOI: 10.1016/j.mtbio.2022.100395.].

The incidence of liquefied petroleum gas (LPG)-related accidents in China has increased over the recent years. In addition, infection remains a big challenge in cases of severe burns. Therefore, the present study aimed to provide valuable information for a better control of infections in the event of such disasters. In this study, a total of 16 patients who suffered extremely severe burns after an LPG tanker explosion were included. Thereafter, bacteriological culture results were collected within a week. Of 16 patients, 13 (81.25%) were male and the average age of all patients was 60.63 years. In addition, the mean burned area was 83.03% TBSA. Additionally, a total of 553 organism cultures were conducted out of which 287 isolates (51.90%) showed positive results. Notably, 38.52% were Gram-negative bacteria, 7.59% were Gram-positive bacteria and 5.79% were fungi. Moreover, the most prevalent Gram-negative bacteria were Stenotrophomonas maltophilia (28.97%) followed by Acinetobacter baumannii (28.53%), and Klebsiella pneumoniae (14.02%). On the other hand, the three most predominant Gram-positive bacteria were Enterococcus faecalis (33.33%), Staphylococcus aureus (28.89%) and Staphylococcus sciuri (17.78%). Furthermore, the most common fungi included Candida (38.24%), Fusarium (20.59%) and Aspergillus fumigatus (14.71%). With regard to the bacterial resistance patterns, carbapenem-resistant organisms included Acinetobacter baumannii (97.80%), Pseudomonas aeruginosa (67.57%), and Klebsiella pneumoniae (75.56%). In addition, Staphylococcus sciuri, Staphylococcus epidermidis, and Staphylococcus haemolyticus were identified to be methicillin-resistant. This study revealed that there was a high incidence of infection in victims of severe burns as a result of mass burn accidents, accompanied by early fungal infection.

Diabetic foot ulcers, typical non-healing wounds, represent a severe clinical problem. Advanced glycation end-products (AGEs), which create a prolonged pro-inflammatory micro-environment in defective sites, can be responsible for refractoriness of these ulcers. Macrophages are polarized to the M2 phenotype to facilitate the transition from a pro-inflammatory microenvironment to an anti-inflammatory microenvironment, which has been demonstrated to be an effective way to accelerate diabetic wound closure. Herein, we developed coaxial hydro-membranes mimicking the extracellular matrix structure that are capable of anti-inflammatory and antibacterial functions for diabetic wound repair. These fibrous membranes maintain a moist microenvironment to support cell proliferation. Macrophages grow in an elongated shape on the surface of the fibrous membranes. The fibrous membranes effectively impaired macrophage AGE-induced M1 polarization and induced macrophage polarization towards the M2 phenotype. The effects of the fibrous membranes on the interactions between macrophages and repair cells under a diabetic condition were also investigated. Furthermore, in vivo results from a full-thickness diabetic wound model confirmed the potential of the coaxial hydro-membranes to accelerate wound healing. This study's results indicate that the developed bioactive anti-inflammatory and antibacterial wound dressing can affect AGE-induced macrophage activation and crosstalk between macrophages and fibroblasts for treating diabetic wounds.

Background Mass burn casualties impose an enormous burden on triage systems. The triage capacity of the Braden Scale for detecting injury severity has not been evaluated in mass burn casualties. Material/Methods The New Injury Severity Score (NISS) was used to dichotomize the injury severity of patients. The Braden Scale and other potentially indicative measurement tools were evaluated using univariate analysis and multivariate logistic regression. The relationships between the Braden Scale and other continuous variables with injury severity were further explored by correlation analysis and fitted with regression models. Receiver operating characteristic (ROC) curve analysis was used to validate triage capacity and compare prognostic accuracy. Results A total of 160 hospitalized patients were included in our study; 37 were severely injured, and 123 were not. Injury severity was independently associated with the Numerical Rating Scale (adjusted OR, 1.816; 95% CI, 1.035–3.187) and Braden Scale (adjusted OR, 0.693; 95% CI, 0.564–0.851). The ROC curve of the fitted quadratic model of the Braden Scale was 0.896 (0.840–0.953), and the cut-off value was 17. The sensitivity was 81.08% (64.29–91.44%) and the specificity was 82.93% (74.85–88.89%). Comparison of ROC curves demonstrated an infinitesimal difference between the Braden Scale and NISS for predicting 30-day hospital discharge (Z=0.291, P=0.771) and Intensive Care Unit admission (Z=2.016, P=0.044). Conclusions The Braden Scale is a suitable triage tool for predicting injury severity and forecasting disability-related outcomes in patients affected by mass burn casualty incidents.

Treatment of full-thickness skin defects still presents a significant challenge in clinical practice. Three-dimensional (3D) bioprinting technique offers a promising approach for fabricating skin substitutes. However, it is necessary to identify bioinks that have both sufficient mechanical properties and desirable biocompatibilities. In this study, we successfully fabricated acellular dermal matrix (ADM) and gelatin methacrylamide (GelMA) bioinks. The results demonstrated that ADM preserved the main extracellular matrix (ECM) components of the skin and GelMA had tunable mechanical properties. Both bioinks with shear-thinning properties were suitable for 3D bioprinting and GelMA bioink exhibited high printability. Additionally, the results revealed that 20% GelMA with sufficient mechanical properties was suitable to engineer epidermis, 1.5% ADM and 10% GelMA displayed relatively good cytocompatibilities. Here, we proposed a new 3D structure to simulate natural full-thickness skin, which included 20% GelMA with HaCaTs as an epidermal layer, 1.5% ADM with fibroblasts as the dermis, and 10% GelMA mesh with human umbilical vein endothelial cells (HUVECs) as the vascular network and framework. We demonstrated that this 3D bioprinting functional skin model (FSM) could not only promote cell viability and proliferation, but also support epidermis reconstruction in vitro. When transplanted in vivo, the FSM could maintain cell viability for at least 1 week. Furthermore, the FSM promoted wound healing and re-epithelization, stimulated dermal ECM secretion and angiogenesis, and improved wound healing quality. The FSM may provide viable functional skin substitutes for future clinical applications.

Background Wound healing is a complex process and the treatment of chronic non-healing wounds still remains a tough challenge. Mesenchymal stem cell (MSC) based therapy has emerged as a promising therapeutic strategy for wound healing. Stem cell factor/stem cell factor receptor (SCF/c-kit) interaction activates downstream signal pathways in stem cells. microRNAs (miRNAs) regulate the effect of adipose tissue-derived stem cells (ADSCs) in cutaneous wound, but the associated cellular mechanisms are not fully understood. In the research, we investigate the inhibitory effect of miR-466 in ADSC migration induced by SCF/c-kit/ERK axis.Methods Human ADSCs were tested by scratch assay and Transwell assay to evaluate the migration ability. MicroRNA sequencing was used to find the discrepancy miRNA in ADSCs with or without SCF pretreatment. The ERK signaling pathway was investigated by pharmacological disruption of PD98059. In addition, siRNA, RT-qPCR, western blotting, and luciferase reporter assay were used to investigate the mechanism of miR-466 regulating migration via the SCF/c-kit/ERK pathway. In the in vivo study, the wound healing ability of miR-466 and SCF was evaluated in a nude mouse full-thickness skin wound model.ResultsADSCs incubated with SCF induces the expression of c-kit and promotes ADSC migration, whereas siRNA c-kit inhibited the effects. microRNAs microarray showed that miR-466 was upregulated in SCF pretreatment ADSCs compared to ADSCs. The luciferase reporter assay indicated that miR-466 may target c-kit and suppress SCF/c-kit-mediated migration of ADSCs. The ERK signaling pathway was confirmed to be involved in SCF/c-kit induced migration. In addition, pre-treatment with PD98059 reversed the effects of SCF/c-kit on the ERK signaling and migration-related proteins. Furthermore, miR-466 inhibits ADSC migration to wound site and defects cutaneous wound healing in vivo.ConclusionsTaken together, our data suggested that SCF/c-kit signal axis can enhance the activation of ERK signal pathway, which will promote ADSC migration. miR-466 regulates ADSC migration by targeting SCF/c-kit/ERK signaling and defects wound healing.