Development of magnesium hydroxide-doped nanofibrous spheres for repairing infected skin wounds.

The healing of skin wounds is a continuous and coordinated process, typically accompanied by microbial colonization and growth. This may result in wound infection and subsequent delay in wound healing. Therefore, it is of particular importance to inhibit the growth of microorganisms in the wound environment. In this study, magnesium hydroxide-doped polycaprolactone (PCL/MH) nanofibrous spheres were fabricated by electrospinning and electrospray techniques to investigate their effects on infected wound healing. The prepared PCL/MH nanofibrous spheres had good porous structure and biocompatibility, providing a favorable environment for the delivery and proliferation of adipose stem cells. The incorporation of MH significantly enhanced the antimicrobial properties of the spheres, in particular, the inhibition of the growth of S. aureus and E. coli. We showed that such PCL/MH nanofibrous spheres had good antimicrobial properties and effectively promoted the regeneration of infected wound tissues, which provided a new idea for the clinical treatment of infected wounds.

Promotion of adipose stem cell transplantation using GelMA hydrogel reinforced by PLCL/ADM short nanofibers.

Adipose-derived mesenchymal stem cells (ADSCs) show poor survival after transplantation, limiting their clinical application. In this study, a series of poly(l-lactide-co-ϵ-caprolactone) (PLCL)/acellular dermal matrix (ADM) nanofiber scaffolds with different proportions were prepared by electrospinning. By studying their morphology, hydrophilicity, tensile mechanics, and biocompatibility, PLCL/ADM nanofiber scaffolds with the best composition ratio (PLCL:ADM = 7:3) were selected to prepare short nanofibers. And based on this, injectable gelatin methacryloyl (GelMA) hydrogel loaded with PLCL/ADM short nanofibers (GelMA-Fibers) was constructed as a transplantation vector of ADSCs. ADSCs and GelMA-Fibers were co-cultured, and the optimal loading concentration of PLCL/ADM nanofibers was investigated by cell proliferation assay, live/dead cell staining, and cytoskeleton stainingin vitro. In vivoinvestigations were also performed by H&E staining, Oil red O staining, and TUNEL staining, and the survival and apoptosis rates of ADSCs transplantedin vivowere analyzed. It was demonstrated that GelMA-Fibers could effectively promote the proliferation of ADSCsin vitro. Most importantly, GelMA-Fibers increased the survival rate of ADSCs transplantation and decreased their apoptosis rate within 14 d. In conclusion, the constructed GelMA-Fibers would provide new ideas and options for stem cell tissue engineering and stem cell-based clinical therapies.

Application of ADSCs and their Exosomes in Scar Prevention.

Scar is a common way of healing after tissue injury. The poor scar healing will not only cause dysfunction of tissues and organs but also affect the appearance of the patients' body surface, which causes the pressure of life and spirit to the patients. However, the formation of scar tissue is an extremely complex process and its mechanism is not fully understood. At present, there is no treatment method to eliminate scars completely. Fibroblasts are the most abundant cells in the dermis, which have the ability to synthesize and remodel extracellular matrix (ECM). Myofibroblasts actively participate in the wound healing process and influence the outcome. Therefore, both of them play important roles in wound healing and scar formation. Adipose tissue-derived stem cells (ADSCs) are pluripotent stem cells that can act on target cells by paracrine. Adipose tissue stem cell-derived exosomes (ADSC-Exos) are important secretory substances of ADSCs. They are nanomembrane vesicles that can transport a variety of cellular components and fuse with target cells. In this review, we will discuss the effects of ADSCs and ADSC-Exos on the behavior of fibroblasts and myofibroblasts during wound healing and scarring stage in combination with recent studies.

Manipulating electrostatic field to control the distribution of bioactive proteins or polymeric microparticles on planar surfaces for guiding cell migration.

We report a general strategy to generate linear and circular gradients of active proteins or polymeric microparticles on planar surfaces by controlling the distribution of electrostatic field during electrohydrodynamic jet printing or electrospray process. Taking fibronectin as an example, we generated a circular gradient of fibronectin and investigated its effect on accelerating the migration of fibroblasts to suit for use in wound closure. In another demonstration, we created linear gradients of laminin in unidirectional and bidirectional patterns, respectively. We showed that such gradations significantly promoted the migration of human neuroblastoma cells with the increase of laminin content. When we changed fibronectin/laminin to electrosprayed poly(lactic-co-glycolic acid) (PLGA) microparticles, we found similar results in terms of guiding cell migration, except that the guidance cues varied from biological signal to topographic structure. Taken together, this method for generating linear/circular gradients of fibronectin/laminin and PLGA microparticles can be readily extended to different types of bioactive proteins and polymeric microparticles to suit wound closure, nerve repair, and related applications involving cell migration.

Cool and hot chitosan/platelet-derived growth factor nanofibers for outdoors burns.

Burns and scalds are thermal injuries caused by a large amount of heat accumulation in local tissues. The first cooling emergency is a key step. However, it is hard that in outdoors to find clean water to cool the scald tissue sites. Moreover, most dressings are concentrated on the treatment process today, neglecting the emergency treatment of temperature reduction. In this study, we imported refrigeration in the electrospinning process while using dirty water, rainwater and even urine of outdoors, so that the cooled sterile fibers were directly deposited on the burn and scald wounds, and the cooling emergency was achieved through the dual cooling mechanism. Since this fiber which is made up of cheap fish gelatin contains CuS adopting the green method, it can generate heat and effectively kill bacteria under the irradiation of an illumination lamp at the front end of a spinning device. As a result of the direct deposition, there is an excellent fit between the fibrous membrane and the skin, which reduces the air gap to achieve a better and quick cooling and heating effects. On the same Chitosan/Platelet-derived Growth Factor fiber membrane, this method of cooling first and heating second can shorten the recovery time from 30 days to 21 days. Thus, this treatment strategy has a great potential application prospect in the field of outdoor burn treatment.

A nanofiber hydrogel derived entirely from ocean biomass for wound healing.

Crustaceans and fish scales in the marine food industry are basically thrown away as waste. This not only wastes resources but also causes environmental pollution. While reducing pollution and waste, biological activity and storage of materials are urgent issues to be solved. In this study, by first preparing dry fibers and then making hydrogels, we prepared a fish scale/sodium alginate/chitosan nanofiber hydrogel (FS-P) by cross-linking the nanofibers in situ. From fish and other organisms, fish gelatin (FG), collagen and CaCO3 were extracted. Fish scale (FS)/sodium alginate/chitosan nanofibers were cross-linked with copper sulfide nanoparticles prepared by a one-step green method to obtain FS-P nanofiber hydrogels under mild conditions without catalyst and additional procedures. These fiber hydrogels not only have good tissue adhesion and tensile properties, but also have the antibacterial effect of natural antibacterial and CuS photothermal synergism, which can achieve 51.32% and 49.96% of the antibacterial effect against Staphylococcus aureus and Escherichia coli respectively, avoiding the generation of superbacteria. The nanofiber hydrogels have 87.56% voidage and 52.68% degradability after 14 days. The combined strategy of using marine bio-based fibers to prepare gels promoted angiogenesis and tissue repair.

Immune Score Indicator for the Survival of Melanoma Patients Based on Tumor Microenvironment.

BACKGROUND: Tumor microenvironment (TME) refers to the cellular environment where tumors exist, including immune cells, fibroblasts, stromal cells, chemokines, etc. TME is closely related to the prognosis of various tumors; nevertheless, limited studies have established predictive prognosis models based on TME. This work aims to construct a survival prediction model for melanoma patients based on TME. METHODS: Data of 482 melanoma patients were extracted from The Cancer Genome Atlas (TCGA) database. Based on the infiltration of immune cells (Immune score), stromal cells (Stromal score), and tumor purity (Estimate score), the "Estimate" algorithm was used to construct 3 scores for each patient. To identify the differentially expressed genes (DEGs), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted using DAVID database and visualized using the R software. The STRING database was used to construct the protein-protein interaction (PPI) network and functional modules. FGD2 expression was confirmed via Western Blotting and quantitative reverse transcription PCR (RT-qPCR) analyses. RESULTS: Patients with higher immune scores estimate scores showed better OS than those with lower scores. All three scores were related to age and primary tumor stage. Further, DEGs between patients with high immune/stromal scores and low immune/stromal scores were screened. Eventually, 10 down-regulated DEGs and 201 up-regulated DEGs were identified as TME associated genes. Out of these, the FGD2 gene demonstrated close association with survival and was confirmed in the included melanoma patients. CONCLUSION: In summary, TME is closely associated with the prognosis of melanoma patients. Besides, genes including FGD2 promote the TME-mediated regulation of melanoma.

Harnessing biocompatible nanofibers and silver nanoparticles for wound healing: Sandwich wound dressing versus commercial silver sulfadiazine dressing.

Owing to the structural replication of native extracellular matrix, nonwoven mats of electrospun nanofibers have great potential for use in wound healing. Herein, we report the design and fabrication of a sandwich wound dressing to balance its antimicrobial activity and biocompatibility. This success mainly relies on the incorporation of silver nanoparticles (AgNPs) into electrospun nanofibers, together with the rational design of a sandwich structure for the dressing. The bottom layer was composed of hydrophilic nanofibers made from a blend of polycaprolactone (PCL) and gelatin (Gel). The top layer consisted of hydrophobic PCL nanofibers. AgNP-loaded PCL/Gel nanofibers were sandwiched between the two layers. When compared with a commercial silver sulfadiazine dressing, the designed wound dressing showed competitive antimicrobial properties, lower cell toxicity, and accelerated wound closure for mouse skin injury. By balancing the biocompatibility of electrospun nanofibers and the broad-spectrum antibacterial activity of AgNPs within a sandwich structure, the novel multifunctional wound dressing could be valuable for effective wound healing and related applications.

LINC00702 suppresses proliferation and invasion in non-small cell lung cancer through regulating miR-510/PTEN axis.

BACKGROUND: Long non-coding RNAs (lncRNAs) have been consistently reported to be involved in the progression of non-small cell lung cancer (NSCLC). In this study, we aimed to identify aberrantly expressed lncRNAs in NSCLC, in order to explore new therapeutic targets for NSCLC. METHODS: Two pairs of NSCLC and adjacent normal tissues were first analyzed by RNA sequencing. The expressions of LINC00702 in 40 pairs patient samples and in 4 NSCLC cell lines was measured by quantitative real-time PCR. Putative target miRNAs of LINC00702 were predicted by the bioinformatics tools. The effect of LINC00702 on tumor growth in vivo was evaluated. RESULTS: LINC00702 was significantly down-regulated in patients with NSCLC, which was correlated with tumor size and metastasis. In addition, overexpression of LINC00702 markedly suppressed proliferation and metastasis in NSCLC cells via inducing apoptosis in vitro and in vivo. Moreover, bioinformatics and luciferase reporter assays demonstrated that LINC00702 functioned as a competing endogenous RNA (ceRNA) for miR-510 in NSCLC, and upregulated its target gene PTEN. CONCLUSION: Our results indicated that LINC00702 modulated the expression of PTEN gene by acting as a ceRNA for miR-510 in NSCLC. Therefore, LINC00702 may serve as a potential target for the diagnosis and treatment of patients with NSCLC.