Differential effects of macrophage subtype-specific cytokines on fibroblast proliferation and endothelial cell function in co-culture system.

Macrophages are involved in several critical activities associated with tissue repair and regeneration. Current approaches in regenerative medicine are focusing on leveraging the innate immune response to accelerate tissue regeneration and improve long-term healing outcomes. Of particular interest in this regard are the currently known, four main M2 macrophage subtypes: M2, M2, M2, M2 (M2 → M2).

Dexamethasone eluting polydopaminated polycaprolactone-poly (lactic-co-glycolic) acid for treatment of tracheal stenosis.

Tracheal stenosis is commonly caused by injury, resulting in inflammation and fibrosis. Inhibiting inflammation and promoting epithelization can reduce recurrence after initial successful treatment of tracheal stenosis. Steroids play an important role in tracheal stenosis management.

A systematic review of underlying genetic factors associated with ureteropelvic junction obstruction in stenotic human tissue.

Objective: Genetic factors are implicated in the development of ureteropelvic junction obstruction (UPJO). The aims of this study were: 1) condense and examine the existing data in studies containing information regarding differential gene expression in tissues from patients with UPJO and 2) investigate associations between genetic markers and their related pathways.

Materials And Methods: A systematic review of studies published between January 2000 and September 2021 was conducted using the following databases: Ovid/Medline, PubMed, Wiley Cochrane Central Register of Controlled Trials, Web of Science, and Scopus.

A preliminary evaluation of in vivo response to a filament-wound macroporous collagen midurethral sling in an ovine model.

Stress urinary incontinence (SUI) impacts ~1/3 of women over age 50. Negative publicity around PP meshes used in pelvic prolapse repair drives the need for identifying alternative biomaterials for SUI repair. Our study evaluated in vivo response to collagen sling implanted in an ovine model.

Mesenchymal Stem Cell Delivery via Topographically Tenoinductive Collagen Biotextile Enhances Regeneration of Segmental Tendon Defects.

Background: Successful management of massive rotator cuff (RC) tendon tears represents a treatment challenge because of the limited intrinsic healing capacity of native tendons and the risk of repair failure. Biologic augmentation of massive RC tears utilizing scaffolds-capable of regenerating bulk tendon tissue to achieve a mechanically functional repair-represents an area of increasing clinical interest.

Purpose: To investigate the histological and biomechanical outcomes after the use of a novel biologic scaffold fabricated from woven electrochemically aligned collagen (ELAC) threads as a suture-holding, fully load-bearing, defect-bridging scaffold with or without mesenchymal stem cells (MSCs) compared with direct repair in the treatment of critically sized RC defects using a rabbit model.

Comparison of Morphological and Histological Characteristics of Human and Sheep: Sheep as a Potential Model for Testing Midurethral Slings in vivo.

Introduction: The sheep was evaluated as a potential model for preclinical evaluation of urethral slings in vivo based on: (1) anatomical measurements of the sheep vagina and (2) histological tissue integration and host response to polypropylene (PP) slings.

Methods: Eight female, multiparous sheep were utilized. Three of 8 animals underwent surgery mimicking human tension-free vaginal tape protocols for midurethral slings and were euthanized at 6 months.

Delivery of M0, M1, and M2 Macrophage Subtypes via Genipin-Cross-Linked Collagen Biotextile.

Developing strategies to regulate the immune response poses significant challenges with respect to the clinical translation of tissue-engineered scaffolds. Prominent advancements have been made relating to macrophage-based therapies and biomaterials. Macrophages exhibit the potential to influence healing trajectory, and predominance of particular subtypes during early onset of healing influences repair outcomes.

Gene network profiling in muscle-invasive bladder cancer: A systematic review and meta-analysis.

Background: Determining meta-analysis of transcriptional profiling of muscle-invasive bladder cancer (MIBC) through Gene Expression Omnibus (GEO) datasets has not been investigated. This study aims to define gene expression profiles in MIBC and to identify potential candidate genes and pathways.

Objectives: To review and evaluate gene expression studies in MIBC through publicly available RNA sequencing (RNA-Seq) and microarray data in order to identify potential prognostic and therapeutic targets for MIBC.

Genipin guides and sustains the polarization of macrophages to the pro-regenerative M2 subtype via activation of the pSTAT6-PPAR-gamma pathway.

M2 macrophages are associated with deposition of interstitial collagen and other extracellular matrix proteins during the course wound healing and also inflammatory response to biomaterials. Developing advanced biomaterials to promote the M2 subtype may be an effective way to improve tissue reinforcement surgery outcomes. In this study, the effect of genipin, a naturally derived crosslinking agent, on M0 → M2-polarization was investigated.

Chondrogenesis of Mesenchymal Stem Cells through Local Release of TGF-β3 from Heparinized Collagen Biofabric.

Osteoarthritic degeneration of cartilage is a major social health problem. Tissue engineering of cartilage using combinations of scaffold and mesenchymal stem cells (MSCs) is emerging as an alternative to existing treatment options such as microfracture, mosaicplasty, allograft, autologous chondrocyte implantation, or total joint replacement. Induction of chondrogenesis in high-density pellets of MSCs is generally attained by soluble exogenous TGF-β3 in culture media, which requires lengthy culture period during which pellets gain mechanical robustness.

Volumetric MicroCT Intensity Histograms of Fatty Infiltration Correlate with the Mechanical Strength of Rotator Cuff Repairs: An Ex Vivo Rabbit Model.

Background: Fatty infiltration of the rotator cuff occurs after injury to the tendon and results in a buildup of adipose in the muscle. Fatty infiltration may be a biomarker for predicting future injuries and mechanical properties after tendon repair. As such, quantifying fatty infiltration accurately could be a relevant metric for determining the success of tendon repairs.

Scalable in-hospital decontamination of N95 filtering face-piece respirator with a peracetic acid room disinfection system.

Background: Critical shortages of personal protective equipment, especially N95 respirators, during the coronavirus disease 2019 (COVID-19) pandemic continues to be a source of concern. Novel methods of N95 filtering face-piece respirator decontamination that can be scaled-up for in-hospital use can help address this concern and keep healthcare workers (HCWs) safe.

Methods: A multidisciplinary pragmatic study was conducted to evaluate the use of an ultrasonic room high-level disinfection system (HLDS) that generates aerosolized peracetic acid (PAA) and hydrogen peroxide for decontamination of large numbers of N95 respirators.

Silica/polycaprolactone nanofiber scaffold variants for human periosteal cell growth.

Polycaprolactone (PCL) nanofiber scaffolds with attached cadaveric human periosteum or its cells were investigated in this study as a tissue-engineering approach to repair nonunion injuries of bone. Addition of silica nanoparticles (silica or nSiO ) to PCL scaffolds was examined for effects on the growth of human periosteal cells in vitro and in vivo. Electrospun PCL nanofiber (nanoPCL) scaffolds were fabricated with different silica contents (0, 0.

Woven collagen biotextiles enable mechanically functional rotator cuff tendon regeneration during repair of segmental tendon defects in vivo.

Despite advancements in surgical techniques and materials for rotator cuff repair procedures, primary repair failures remain common. This study examines the use of electrochemically aligned collagen (ELAC) threads woven into biotextile scaffolds as grafts to repair critical infraspinatus tendon defects in New Zealand White rabbits. Three surgical treatment groups were evaluated: rabbits undergoing direct repair as operative controls, rabbits receiving ELAC scaffolds alone, and rabbits treated with mesenchymal stem cell (MSC)-seeded ELAC scaffolds.

In vivo biocompatibility and time-dependent changes in mechanical properties of woven collagen meshes: A comparison to xenograft and synthetic mid-urethral sling materials.

Meshes woven from highly aligned collagen threads crosslinked using either genipin or 1-ethyl-3-(3-dimethylaminopropyl) carboiimide and N-hydroxy succinimide (EDC/NHS) were implanted in a subcutaneous rat model to evaluate their biocompatibility (at 2 weeks, 2 months, and 5 months), mechanical properties (at baseline, 2 months, and 5 months) and ultimately their suitability for use as mid-urethral slings (MUS) for management of stress urinary incontinence. Porcine dermal (Xenmatrix) and monofilament polypropylene (Prolene) meshes were also implanted to provide comparison to clinically used materials. Quantitative histological scoring showed tissue integration in Xenmatrix was almost absent, while the open network of woven collagen and Prolene meshes allowed for cellular and tissue integration.

A Method for the Immunohistochemical Identification and Localization of Osterix in Periosteum-Wrapped Constructs for Tissue Engineering of Bone.

A novel immunohistochemistry (IHC) approach has been developed to label and localize osterix, a bone-specific transcription factor, within formalin-fixed, paraffin-embedded, tissue-engineered constructs uniquely containing synthetic polymers and human periosteal tissue. Generally, such specimens consisting in part of polymeric materials and mineral are particularly difficult for IHC identification of proteins. Samples here were fabricated from human periosteum, electrospun poly-l-lactic acid (PLLA) nanofibers, and polycaprolactone/poly-l-lactic acid (PCL/PLLA, 75/25) scaffolds and harvested following 10 weeks of implantation in athymic mice.

Recent Applications of Coaxial and Emulsion Electrospinning Methods in the Field of Tissue Engineering.

Electrospinning has emerged as an effective method of producing nanoscale fibers for use in multiple fields of study. One area of significant interest is nanofiber utilization for tissue engineering because the nanofibrous mats can mimic the native extracellular matrix of biological tissues. A logical next step is the inclusion of certain molecules and compounds to accelerate or increase the efficacy of tissue regeneration.

Mechanical Properties, Cytocompatibility and Manufacturability of Chitosan:PEGDA Hybrid-Gel Scaffolds by Stereolithography.

Extracellular matrix mimetic hydrogels which hybridize synthetic and natural polymers offer molecularly-tailored, bioactive properties and tunable mechanical strength. In addition, 3D bioprinting by stereolithography allows fabrication of internal pores and defined macroscopic shapes. In this study, we formulated a hybrid biocompatible resin using natural and synthetic polymers (chitosan and polyethylene glycol diacrylate (PEGDA), respectively) by controlling molecular weight of chitosan, feed-ratios, and photo-initiator concentration.

Effects of FGF-2 and OP-1 in vitro on donor source cartilage for auricular reconstruction tissue engineering.

Objective: Microtia is a congenital partial or total loss of the external ear with current treatment approaches involving autologous construction from costal cartilage. Alternatively, tissue engineering provides possible use of normal or microtia auricular chondrocytes harvested from patients. This study investigated effects in vitro of basic fibroblast growth factor (FGF-2) and osteogenic protein 1 (OP-1) on human pediatric normal and microtia auricular chondrocytes and their potential proliferation and differentiation for cellular expansion.