Endogenous stimuli-responsive separating microneedles to inhibit hypertrophic scar through remodeling the pathological microenvironment

Hypertrophic scar (HS) considerably affects the appearance and causes tissue dysfunction in patients. The low bioavailability of 5-fluorouracil poses a challenge for HS treatment. Here we show a separating microneedle (MN) consisting of photo-crosslinked GelMA and 5-FuA-Pep-MA prodrug in response to high reactive oxygen species (ROS) levels and overexpression of matrix metalloproteinases (MMPs) in the HS pathological microenvironment. In vivo experiments in female mice demonstrate that the retention of MN tips in the tissue provides a slowly sustained drug release manner. Importantly, drug-loaded MNs could remodel the pathological microenvironment of female rabbit ear HS tissues by ROS scavenging and MMPs consumption. Bulk and single cell RNA sequencing analyses confirm that drug-loaded MNs could reverse skin fibrosis through down-regulation of BCL-2-associated death promoter (BAD), insulin-like growth factor 1 receptor (IGF1R) pathways, simultaneously regulate inflammatory response and keratinocyte differentiation via up-regulation of toll-like receptors (TOLL), interleukin-1 receptor (IL1R) and keratinocyte pathways, and promote the interactions between fibroblasts and keratinocytes via ligand-receptor pair of proteoglycans 2 (HSPG2)-dystroglycan 1(DAG1). This study reveals the potential therapeutic mechanism of drug-loaded MNs in HS treatment and presents a broad prospect for clinical application.

Identification and validation of CCR5 linking keloid with atopic dermatitis through comprehensive bioinformatics analysis and machine learning

There is sufficient evidence indicating that keloid is strongly associated with atopic dermatitis (AD) across ethnic groups. However, the molecular mechanism underlying the association is not fully understood. The aim of this study is to discover the underlying mechanism of the association between keloid and AD by integrating comprehensive bioinformatics techniques and machine learning methods. The gene expression profiles of keloid and AD were downloaded from the Gene Expression Omnibus (GEO) database. A total of 449 differentially expressed genes (DEGs) were found to be shared in keloid and AD using the training datasets of GEO (GSE158395 and GSE121212). The hub genes were identified using the protein-protein interaction network and Cytoscape software. 20 of the most significant hub genes were selected, which were mainly involved in the regulation of the inflammatory and immune response. Through two machine learning algorithms of LASSO and SVM-RFE, CCR5 was identified as the most important key gene. Subsequently, upregulated CCR5 gene expression was confirmed in validation GEO datasets (GSE188952 and GSE32924) and clinical samples of keloid and AD. Immune infiltration analysis showed that T helper (Th) 1, 2 and 17 cells were significantly enriched in the microenvironment of both keloid and AD. Positive correlations were found between CCR5 and Th1, Th2 and Th17 cells. Finally, two TFs of CCR5, NR3C2 and YY1, were identified, both of which were downregulated in keloid and AD tissues. Our study firstly reveals that keloid and AD shared common inflammatory and immune pathways. Moreover, CCR5 plays a key role in the pathogenesis association between keloid and AD. The common pathways and key genes may shed light on further mechanism research and targeted therapy, and may provide therapeutic interventions of keloid with AD.

Self-adhesive Hyaluronic Acid/Antimicrobial Peptide Composite Hydrogel with Antioxidant Capability and Photothermal Activity for Infected Wound Healing

Bacterial infection can delay wound healing, causing wounds to deteriorate and even threatening the patient's life. Recently, although many composite hydrogels as wound dressing have been developed, it is still highly desired to construct photothermal hydrogels with antimicrobial and antioxidant properties to accelerate the infected wound healing. In this work, we develop a hyaluronic acid (HA)-based composite hydrogel consisting of a dopamine-substituted antimicrobial peptide (DAP) and Iron (III) ions, which exhibits photothermal-assisted promotion and acceleration of healing process of bacteria-infected wounds. DAP, serving as both antimicrobial agent and ROS-scavenger, forms Schiff's base bonds with aldehyde hyaluronic acid (AHA) and iron-catechol coordination bonds to reinforce the composite hydrogel. The presence of Fe³⁺ can also promote covalent polymerization of dopamine, which endows the hydrogel with photothermal capacity. The in vitro and in vivo experiments prove that the composite hydrogel can effectively accelerate the infected wound healing process, including antibacterial, accelerated collagen deposition and re-epithelization. This study suggests that the multifunctional composite hydrogel possesses remarkable potential for bacteria-infected wound healing by combining inherent antimicrobial activity, antioxidant capability and photothermal effect. This article is protected by copyright. All rights reserved.

Comparing the Accuracy of ABCD-10 and SCORTEN in Predicting the In-Hospital Mortality of Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis: A Multi-Institutional Study from Central China

BACKGROUND

The newly described ABCD-10 (age, bicarbonate, cancer, dialysis, 10% body surface area [BSA]) is a 5-item mortality prediction model for patients with Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). It was developed in the United States, has at present been externally tested only in the United States, Spain, and Singapore, and remains to be validated in resource-restricted settings. We sought to compare the accuracy of ABCD-10 and Score of Toxic Epidermal Necrolysis (SCORTEN) in predicting in-hospital mortality in a cohort from central China. Due to disease progression affecting the accuracy of the prediction model during hospitalization, for example, higher predictive accuracy of SCORTEN based on parameters collected on day 3 of hospitalization, we also assessed the overall predictive value of ABCD-10 on days 1 and 3, respectively.

METHODS

A retrospective study was performed over a 10-year period (2010-2020) from 3 medical institutions in Wuhan. The performance of predictive models was assessed by both discrimination and calibration. Receiver-operating characteristic (ROC) curves, Hosmer-Lemeshow goodness-of-fit tests and calibration plots were used to evaluate the model discrimination and calibration.

RESULTS

Of 84 included patients, 11 (13.1%) did not survive. The discrimination power of ABCD-10 was not significantly different from that of SCORTEN (area under the curve: day 1, p > 0.05; day 3, p > 0.05). Although the calibration of ABCD-10 was good, it was inferior to SCORTEN as it underestimated total mortality (Hosmer-Lemeshow goodness-of-fit test: day 1, p = 0.17 vs. p = 0.63; day 3, p = 0.35 vs. p = 0.93). Besides, the performance of ABCD-10 was slightly better on day 3 relative to day 1. During hospitalization, bacteremia developed in 21 (25.0%) patients, which was associated with a higher risk of death in our cohort (odds ratio, 22.88; 95% CI, 4.38-119.40; p < 0.001).

CONCLUSION

ABCD-10 showed acceptable overall performance, but revealed mortality underestimation and was inferior to the performance of SCORTEN. In consistence with SCORTEN, ABCD-10 was a better model when using values collected at day 3 of hospitalization relative to day 1.

Dopamine-Substituted Multidomain Peptide Hydrogel with Inherent Antimicrobial Activity and Antioxidant Capability for Infected Wound Healing

Wound infection can cause a delay in wound healing or even wound deterioration, threatening patients' lives. The excessive accumulation of reactive oxygen species (ROS) in infected wounds activates a strong inflammatory response to delay wound healing. Therefore, it is highly desired to develop hydrogels with inherent antimicrobial activity and antioxidant capability for infected wound healing. Herein, a dopamine-substituted multidomain peptide (DAP) with inherent antimicrobial activity, strong skin adhesion, and ROS scavenging has been developed. DAP can form bilayer β-sheets with dopamine residues on the surface of nanofibers. The enhanced rheological properties of DAP-based hydrogel can be achieved not only through UV irradiation but also by incorporation of multivalent ions (e.g., PO₄^3-). Furthermore, the DAP hydrogel shows a broad spectrum of antimicrobial activity due to the high positive charges of lysine residues and the β-sheet formation. When applied to full-thickness dermal wounds in mice, the DAP hydrogel results in a significantly shortened inflammatory stage of the healing process because of its remarkable antimicrobial activity and antioxidant capability. Accelerated wound closure with thick granulation tissue, uniform collagen arrangement, and dense vascularization can be achieved. This work suggests that the DAP hydrogel can serve as antimicrobial coating and ROS-scavenging wound dressing for bacterial-infected wound treatment.

Injectable and pH-Sensitive Hyaluronic Acid-Based Hydrogels with On-Demand Release of Antimicrobial Peptides for Infected Wound Healing

Antibiotics' abuse in bacteria-infected wounds has threatened patients' lives and burdened medical systems. Hence, antibiotic-free hydrogel-based biomaterials, which exhibit biostability, on-demand release of antibacterial agents, and long-lasting antimicrobial activity, are highly desired for the treatment of chronic bacteria-infected wounds. Herein, we developed a hyaluronic acid (HA)-based composite hydrogel, with an antimicrobial peptide [AMP, KK(SLKL)₃KK] as a cross-linking agent through Schiff's base formation, which exhibited an acidity-triggered release of AMP (pathological environment in bacteria-infected wounds, pH ∼ 5.5-5.6). During the self-assembly process, AMP adopted an antiparallel β-sheet secondary structure due to the alternate arrangement of hydrophobic and hydrophilic residues of amino acids. Owing to Schiff's base formation between the primary amines derived from lysine residues and the aldehydes in oxidized HA, the AMP-HA composite hydrogel exhibited injectability, high biostability, and enhanced mechanical strength. Importantly, both AMP and the AMP-HA composite showed excellent broad-spectrum antibacterial activity in vitro and in vivo. Specifically, the AMP-HA composite hydrogel exhibited on-demand full thickness wound healing in an infected mice model. Therefore, this work provides an efficient strategy to fabricate antibiotic-free hydrogel-based biomaterials for the management of chronic bacteria-infected wounds.

Correlation between the hemoporfin-mediated photodynamic treatment response and the dermoscopy vascular pattern in patients with a port-wine stain: a prospective study

BACKGROUND

Vascular targeted photodynamic therapy (PDT) is a novel and promising therapy for the treatment of port-wine stains (PWS). There has been little prior exploration to our knowledge of how the dermatological vascular pattern may predict the response to PDT.

OBJECTIVES

To analyse whether the vascular pattern classifications of PWS by dermoscopy can predict the efficacy of PDT.

METHODS

This prospective cohort study included 163 patients with a clinical diagnosis of PWS who were treated twice with hemoporfin-mediated photodynamic therapy (HMME-PDT) at two-month intervals and followed up for 6 months. The vascular manifestations of dermoscopy with PWS were independently classified into 8 categories by 3 dermatologists. Images of the lesions were taken using VISIA, and the vascular patterns were imaged by dermoscopy by the same investigator. Images were captured before and after each treatment. The efficacy was evaluated with pre- and post-treatment VISIA images, and correlations between efficacy and vascular patterns were analysed by four dermatologists in a blinded and independent manner, between 10 January 2019 and 11 December 2019.

RESULTS

In the dermoscopy images for the whole cohort, dotted and globular vessels (15.3%), short clubbed vessels (18.4%) and curved vessels (12.9%) were highly associated with cure and beneficial treatment effects. Pale halos surrounding brown dots (8.0%) and arborizing vessels (9.8%) were mainly correlated with skin lesion alleviation. Mixed vessels (12.9%), a grey-whitish veil (11.7%) and reticular patterns (11.0%) were mainly associated with no effect. The differences between each subgroup were statistically significant (P = 0.000).

CONCLUSIONS

There is a clear correlation between the efficacy of PDT and the dermoscopy pattern in patients with PWS. Dermoscopy may therefore provide very useful clinical information prior to treatment in these cases. In addition, the vascular manifestations of PWS determined by dermoscopy help to predict response to PDT and manage patient expectations.

Prognostic significance of tumor size for primary invasive cutaneous melanoma: A population-based study, 2004-2016

Background

This study aimed to assess the independent prognostic value of tumor size compared with other clinical and pathologic features of primary invasive cutaneous melanoma (CM).

Methods

This study included 28,593 patients with primary invasive CM in Surveillance, Epidemiology, and End Results Program database diagnosed from 2004 through 2016. Tumor size was divided into five subgroups (≤6, 7‐12, 13‐30, 31‐42, and >42 mm). The primary endpoint was melanoma‐specific survival (MSS).

Results

The relationship between tumor size and survival was piecewise. After adjusting for age, sex, primary site, histopathologic cell type, Breslow thickness, ulceration, mitotic rate, regional metastasis, and distant metastasis, the hazard ratio (HR) of MSS increased with increasing tumor size until a peak at 31‐42 mm (HRs, 1.33, 1.59, 2.41, respectively; all P < .0001), and then decreased when tumor size was larger than 42 mm using tumor size ≤ 6 mm as the reference (HR, 2.11; 95% confidence interval [CI], 1.84 −2.42; P < .0001). This pattern mostly remained after stratification by T subcategories from T1 to T4 in localized primary CM except that tumor size >42 mm subgroup had the shortest MSS in T4. In addition, tumor size with a cutoff value of 12 mm showed stronger prognostic value for MSS (HR, 2.32; 95% CI, 1.80‐2.98; P < .0001) than Breslow thickness and mitotic rate in primary CM with T1N0M0.

Conclusions

Tumor size was an important independent prognostic factor for MSS in patients with primary invasive CM. Tumor size larger than 30 mm would provide additional and important prognostic information in each T subcategory of localized CM. Furthermore, tumor size with a cutoff value of 12 mm has great potential in improving the accuracy of melanoma T1 substaging.

Scaling Behavior of Quasi-One-Dimensional Vortex Avalanches in Superconducting Films

Scaling behaviour of dynamically driven vortex avalanches in superconducting YBa2Cu3O7-δ films deposited on tilted crystalline substrates has been observed using quantitative magneto-optical imaging. Two films with different tilt angles are characterized by the probability distributions of avalanche size in terms of the number of moving vortices. It is found in both samples that these distributions follow power-laws over up to three decades, and have exponents ranging between 1.0 and 1.4. The distributions also show clear finite-size scaling, when the system size is defined by the depth of the flux penetration front - a signature of self-organized criticality. A scaling relation between the avalanche size exponent and the fractal dimension, previously derived theoretically from conservation of the number of magnetic vortices in the stationary state and shown in numerical simulations, is here shown to be satisfied also experimentally.

Ethanol-induced neurodegeneration in NRSF/REST neuronal conditional knockout mice

The transcription regulator, neuron-restrictive silencer factor (NRSF), also known as repressor element-1 silencing transcription factor (REST), plays an important role in neurogenesis and various neuronal diseases such as ischaemia, epilepsy, and Huntington's disease. In these disease processes, neuronal loss is associated with abnormal expression and/or localization of NRSF. Previous studies have demonstrated that NRSF regulates the effect of ethanol on neuronal cells in vitro, however, the role of NRSF in ethanol-induced neuronal cell death remains unclear. We generated nrsf conditional knockout mice using the Cre-loxP system to disrupt neuronal expression of nrsf and its truncated forms. At postnatal day 6, ethanol significantly increased the expression of REST4, a neuron-specific truncated form of NRSF, in the brains of wild type mice, and this effect was diminished in nrsf conditional knockout mice. The apoptotic effect of ethanol was pronounced in multiple brain regions of nrsf conditional mutant mice. These results indicate that NRSF, specifically REST4, may protect the developing brain from ethanol, and provide new evidence that NRSF can be a therapeutic target in foetal alcohol syndrome (FAS).

[A case of adult onset phosphoglucomutase deficiency]

A case of 38-year-old male with adult onset phosphoglucomutase (PGM) deficiency was reported. The patient was admitted at Kawamura Hospital (Gifu City) for evaluation of easy fatiguability and exercise-induced weakness of the extremities since he was 20 years old. Physical examination revealed moderate muscle weakness, wasting of extremities, bilateral clubbed fingers and hypoesthesia of distal portion of extremities. Fasting plasma glucose was low (58 mg/dl). Venous concentration of lactate failed to rise after an ischemic forearm exercise test. An epinephrine tolerance test revealed hyperglycemic response. Studies of anaerobic glycolysis in vitro using muscle homogenates with the substrate between glucose-1-phosphate and glucose-6-phosphate showed decreased lactate production. Direct assay of individual muscle glycolytic enzymes demonstrated reduction of PGM activity (15% of normal, n = 12). Biopsy study with PAS staining of quadriceps femoris muscle demonstrated small amount of deeply staining glycogen in subsarcolemmal area. Electron microscopic examination revealed muscle destruction with small amount of glycogen in subsarcolemmal and intermyofibrillar spaces. Sural nerve biopsy showed degeneration of myelinated and unmyelinated fibers but there was no apparent accumulation of glycogen. From the clinical, biochemical and histopathological evidences, the patient might be a rare case of adult onset PGM deficiency.