Tissue healing

Human mesenchymal stem cells (hMSCs) dynamically remodel their microenvironment during basic processes, such as migration and differentiation. Migration requires extracellular matrix invasion, necessitating dynamic cell-material interactions. Understanding these interactions is critical to advancing materials designs that harness and manipulate these processes for applications including wound healing and tissue regeneration. In this work, we encapsulate hMSCs in a cell-degradable poly(ethylene glycol)-peptide hydrogel to determine how cell-secreted enzymes, specifically matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs), create unique pericellular microenvironments...

Wound healing is a physiological event that generates reconstitution and restoration of granulation tissue that ends with scar formation. As omega fatty acids are part of membrane phospholipids and participate in the inflammatory response, we investigated the effects of omega-3, omega-6, and omega-9 fatty acids in the form of oils on wound healing. Linseed (LO), evening primrose (EPO), and olive oils (OO) rich in omega-3, omega-6, and omega-9 fatty acids were formulated into emulsions and were topically applied on rats with excision wounds...

The antagonist-specific regulation in tissue engineering constitutes important attempts to achieve an improved and rapid bone regeneration by controlling the natural biological response of the natural body growth factors. L51P is molecularly engineered bone morphogentic protein-2 (BMP-2) variant with a substitution of the 51st leucine with a proline residue. L51P is deficient in BMP receptor binding, but maintains its structure and affinity for inhibitory proteins such as noggin, chordin, and gremlin. These modifications convert the BMP-2 variant L51P into a receptor-inactive inhibitor of BMP antagonists...

Hyperthermia has been considered as a promising healing treatment in bone regeneration. We designed a tissue engineering hydrogel based on magnetic nanoparticles to explore the characteristics of hyperthermia for osteogenic regeneration. This nanocomposite hydrogel was successfully fabricated by incorporating magnetic Fe3 O4 nanoparticles into chitosan/polyethylene glycol (PEG) hydrogel, which showed excellent biocompatibility and were able to easily achieve increasing temperatures under an alternative magnetic field (AMF)...

Severe trauma is accompanied by a profound activation of the immune system. Patients with polytrauma develop systemic inflammatory response syndrome (SIRS) and often sepsis, which contributes substantially to high mortality of this condition. On a cellular level, necrosis and loss of plasma membrane integrity lead to the release of endogenous "damage-associated molecular patterns" (DAMPs) as danger signals, which in turn activate innate immune cells. Inflammation that occurs in the absence of invading pathogens has been termed sterile inflammation and trauma with tissue damage represents an acute form of sterile inflammation...

BACKGROUND: Our previous study demonstrated a close relationship between NOTCH signaling pathway and salivary adenoid cystic carcinoma (SACC). HES1 is a well-known target gene of NOTCH signaling pathway. The purpose of the present study was to further explore the molecular mechanism of HES1 in SACC. METHODS: Comparative transcriptome analyses by RNA-Sequencing (RNA-Seq) were employed to reveal NOTCH1 downstream gene in SACC cells. Immunohistochemical staining was used to detect the expression of HES1 in clinical samples...

Objective This study was performed to investigate the effect of Nocardia rubra cell wall skeleton (N-CWS) on wound healing of full-thickness skin defects. Methods Two 2- × 2-cm full-thickness wounds, one on each side of the midline, were made on the back of 12 rats. One wound was covered with Vaseline gauze soaked in normal saline, whereas the other was covered with Vaseline gauze and N-CWS. Wound dressings were changed every other day from day 0 (wound creation) to day 11. Four of the 12 rats were killed on day 7, and biopsy samples were obtained for biochemical and histopathological analyses...

Tissue regeneration involves versatile kinds of cells. The accumulation and disorganized behaviors of undesired cells impair natural healing process, leading to uncontrolled immune response, restenosis, and/or fibrosis. The cell-selective surfaces and interfaces can have specific and positive effects to the desired types of cells, allowing tissue regeneration with restored structures and functions. This review outlines the importance of surfaces and interfaces of biomaterials with cell-selective properties...

BACKGROUND OBJECTIVES: The past decade has witnessed a rapid expansion of photobiomodulation (PBM), demonstrating encouraging results for the treatment of cutaneous disorders. Confidence in this approach, however, is impaired not only by a lack of understanding of the light-triggered molecular cascades but also by the significant inconsistency in published experimental outcomes, design of the studies and applied optical parameters. This study aimed at characterizing the response of human dermal fibroblast subpopulations to visible and near-infrared (NIR) light in an attempt to identify the optical treatment parameters with high potential to address deficits in aging skin and non-healing chronic wounds...

OBJECTIVE: To determine factors associated with nonunion of adult tibial fractures. DESIGN: Retrospective review with data collection for logistic regression and survival analysis. SETTING: Scottish Level I trauma centre, 1985 to 2007. PATIENTS: During this period, 1,590 adult tibial fractures were treated by reamed nailing and 1,003 met all inclusion criteria for the chosen analysis. INTERVENTION: Reamed intramedullary nailing...

Natural and synthetic materials have been developed to provide a three-dimensional (3-D) scaffold that mimics the extracellular matrix properties for tissue regeneration and reconstruction. On account of the excellent biological and mechanical properties, diverse decellularized tissue materials have been developed as natural scaffolds. Among them, decellularized adipose tissue (DAT) has generated great interest in recent years due to the extensiveness of the source and the eximious potential to enhance the regeneration and repair of damaged tissues...

Fibroblasts are a dynamic cell type that achieve selective differentiated states to mediate acute wound healing and long-term tissue remodeling with scarring. With myocardial infarction injury, cardiomyocytes are replaced by secreted extracellular matrix proteins produced by proliferating and differentiating fibroblasts. Here, we employed 3 different mouse lineage-tracing models and stage-specific gene profiling to phenotypically analyze and classify resident cardiac fibroblast dynamics during myocardial infarction injury and stable scar formation...

Skin and skin appendages protect the body from harmful environment and prevent internal organs from dehydration. Superficial epidermal wounds usually heal without scarring, however, deep dermal wound healing commonly ends up with nonfunctioning scar formation with substantial loss of skin appendage. Wound healing is one of the most complex dynamic biological processes, during which a cascade of biomolecules combine with stem cell influx and matrix synthesis and synergistically contribute to wound healing at all levels...

CaSO4 /CaPO4 -TCP bone graft substitute has been shown to be effective for treatment of bone lesion defects, but its mechanical, histological, and radiographic characteristics have not been studied in direct comparison with a conventional treatment such as cancellous allograft bone. Thirteen canines had a critical-size axial defect created bilaterally into the proximal humerus. CaSO4 /CaPO4 -TCP bone graft substitute (PRO-DENSE™, Wright Medical Technology) was injected into the defect in one humerus, and an equal volume of freeze-dried cancellous allograft bone chips was placed in the contralateral defect...

Supramolecular building block, such as cucurbit[n]uril (CB[n])-based host-guest complexes, have been extensively studied at the nano- and microscale as adhesion promoters. Herein, we exploit a new class of CB[n]-threaded highly-branched polyrotaxanes (HBP-CB[n]) as aqueous adhesives to macroscopically bond two wet surfaces, including biological tissue, through the formation of CB[8] heteroternary complexes. The dynamic nature of these complexes gives rise to adhesion with remarkable self-healing, displaying recovery and re-adhesion after mechanical failure at the interface...

Adipose tissue contains a heterogeneous population of stromal vascular fraction (SVF) cells that work synergistically with resident cell types to enhance tissue healing. Ease of access and processing paired with therapeutic promise make SVF cells an attractive option for autologous applications in regenerative medicine. However, inherent variability in SVF cell therapeutic potential from one patient to another hinders prognosis determination for any one person. This study investigated the regenerative properties and inflammation responses of thirteen, medically diverse human donors...

Heterotopic ossification (HO) is a pathological phenomenon in which ectopic lamellar bone forms in soft tissues. HO involves many predisposing factors, including congenital and postnatal factors. Postnatal HO is usually induced by fracture, burn, neurological damage (brain injury and spinal cord injury) and joint replacement. Recent studies have found that patients who suffered from bone fracture combined with severe traumatic brain injury (S-TBI) are at a significantly increased risk for HO occurrence. Thus, considerable research focused on the influence of S-TBI on fracture healing and bone formation, as well as on the changes in various osteogenic factors with S-TBI occurrence...

The identification of stem cells and growth factors as well as the development of biomaterials hold great promise for regenerative medicine applications. However, the therapeutic efficacy of regenerative therapies can be greatly influenced by the host immune system, which plays a pivotal role during tissue repair and regeneration. Therefore, understanding how the immune system modulates tissue healing is critical to design efficient regenerative strategies. While the innate immune system is well known to be involved in the tissue healing process, the adaptive immune system has recently emerged as a key player...

BACKGROUND: Peroxidasin (PXDN) is an extracellular matrix protein with peroxidase activity. PXDN has been reported to participate in the processes of epithelial mesenchymal transition. However, the roles of PXDN in progression of cancers are still rare. METHODS: Expression profiles of PXDN in ovarian cancer (OC) tissues were obtained from GEO and TCGA database. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to measure the expression of PXDN in OC cells...

Fibular fractures in the setting of an unstable ankle joint require surgical fixation; however, several factors contradict open surgical correction. Severe soft tissue compromise can delay adequate fracture reduction and preclude the standard incisional approach. The soft tissue envelope in the setting of obesity, diabetes, and/or peripheral vascular disease further complicates definitive treatment. Poorly timed open fixation can lead to delayed healing of the incision site, with wound breakdown and the potential for hardware failure...