Development of Functional and Hydrolytically Stable Vinyl Monomers as Methacrylate Dental Resin Restorative Alternatives.

Dental resin-based restorative (RBR) materials represent the most ubiquitous biomaterials utilized globally. Methacrylate (MA)-ester based monomers - present in RBRs since the 1960s - experience significantly elevated rates of failure compared to previously used silver/amalgam fillings attributed to their hydrolysis reported in both simulated and in vivo environments. There is currently no alternative RBR chemistry that matches the functional and clinical workflow considerations of MA-RBRs while addressing their limited-service lives.

Delivery of N-Cadherin Targeting Peptides to Vascular Tissues by Surface-Modified Polyurethane Nanoparticles via a Drug-Coated Balloon.

Restenosis remains a long-standing limitation to effectively maintain functional blood flow after percutaneous transluminal angioplasty (PTA). While the use of drug-coated balloons (DCBs) containing antiproliferative drugs has improved patient outcomes, limited tissue transfer and poor therapeutic targeting capabilities contribute to off-target cytotoxicity, precluding adequate endothelial repair. In this work, a DCB system was designed and tested to achieve defined arterial delivery of an antirestenosis therapeutic candidate, cadherin-2 (N-cadherin) mimetic peptides (NCad), shown to selectively inhibit smooth muscle cell migration and limit intimal thickening in early animal PTA models.

Nanoparticles for the Delivery of Pro-regenerative Cardiac Progenitor Secretory Proteins Targeting Cellular Senescence and Vasculogenesis.

Contemporary therapies following heart failure center on regenerative approaches to account for the loss of cardiomyocytes and limited regenerative capacity of the adult heart. While the delivery of cardiac progenitor cells has been shown to improve cardiac function and repair following injury, recent evidence has suggested that their paracrine effects (or secretome) provides a significant contribution towards modulating regeneration, rather than the progenitor cells intrinsically. The direct delivery of secretory biomolecules, however, remains a challenge due to their lack of stability and tissue retention, limiting their prolonged therapeutic efficacy.

Biomaterials' enhancement of immunotherapy for breast cancer by targeting functional cells in the tumor micro-environment.

Immunotherapy for breast cancer is now being considered clinically, and more recently, the number of investigations aimed specifically at nano-biomaterials-assisted immunotherapy for breast cancer treatment is growing. Alterations of the breast cancer micro-environment can play a critical role in anti-tumor immunity and cancer development, progression and metastasis. The improvement and rearrangement of tumor micro-environment (TME) may enhance the permeability of anti-tumor drugs.

Synthesis, characterization, and surface modification of degradable polar hydrophobic ionic polyurethane nanoparticles for the delivery of therapeutics to vascular tissue.

Degradable polar hydrophobic ionic polyurethanes (D-PHI) are an emerging class of biomaterials with particular significance for blood-contacting applications due to their immunomodulatory effects and highly customizable block chemistry. In this manuscript, D-PHI polymer was formulated as a nanoparticle excipient for the first time by inverse emulsion polymerization. The nanoparticles were optimized with consideration of diameter, surface charge, size variability, and yield as a delivery vehicle for a custom vascular therapeutic peptide.

Biohacking Nerve Repair: Novel Biomaterials, Local Drug Delivery, Electrical Stimulation, and Allografts to Aid Surgical Repair.

The regenerative capacity of the peripheral nervous system is limited, and peripheral nerve injuries often result in incomplete healing and poor outcomes even after repair. Transection injuries that induce a nerve gap necessitate microsurgical intervention; however, even the current gold standard of repair, autologous nerve graft, frequently results in poor functional recovery. Several interventions have been developed to augment the surgical repair of peripheral nerves, and the application of functional biomaterials, local delivery of bioactive substances, electrical stimulation, and allografts are among the most promising approaches to enhance innate healing across a nerve gap.

Synthesis and challenges of fluorinated divinyl urethane monomers as a strategy for masking hydrolytic sensitive methacrylate groups in resin composites.

Objective: The biodegradation of methacrylate (MA)-based dental restoratives has been suggested to contribute to a loss of adhesion and subsequent detachment, or secondary caries, both major causes of restoration failure. Previous studies have demonstrated that intermolecular interactions between resin monomers may affect the hydrolytic-susceptibility of composites. Altering the intermolecular interactions by shielding or masking the hydrolytically-susceptible ester groups found in MA monomers could be an effective strategy to mitigate the biodegradation of resin composites.

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair.

JOURNAL/nrgr/04.03/01300535-202501000-00036/figure1/v/2024-05-14T021156Z/r/image-tiff Axonal regeneration following surgical nerve repair is slow and often incomplete, resulting in poor functional recovery which sometimes contributes to lifelong disability. Currently, there are no FDA-approved therapies available to promote nerve regeneration.

BoneTape: A novel osteosynthetic device for the stabilization of zygomatic fractures.

Background: The study aims to assess the safety and effectiveness of BoneTape™, a new resorbable bone fixation device, using a zygomatic fracture model in rabbits.

Methods: The study followed BoneTape™ samples and control (sham) groups over 2-, 6-, and 12-week periods post-zygomaticomaxillary (ZM) osteotomy and zygomaticofrontal (ZF) disarticulation. The osteotomized segments were analyzed for bone healing, inflammatory response, and tissue healing.

Senescent response in inner annulus fibrosus cells in response to TNFα, H2O2, and TNFα-induced nucleus pulposus senescent secretome.

Senescence, particularly in the nucleus pulposus (NP) cells, has been implicated in the pathogenesis of disc degeneration, however, the mechanism(s) of annulus fibrosus (AF) cell senescence is still not well understood. Both TNFα and H2O2, have been implicated as contributors to the senescence pathways, and their levels are increased in degenerated discs when compared to healthy discs. Thus, the objective of this study is to identify factor(s) that induces inner AF (iAF) cell senescence.

Paracrine cross-talk between human adipose tissue-derived endothelial cells and perivascular cells accelerates the endothelialization of an electrospun ionomeric polyurethane scaffold.

The ex vivo endothelialization of small diameter vascular prostheses can prolong their patency. Here, we demonstrate that heterotypic interactions between human adipose tissue-derived endothelial cells and perivascular cells can be exploited to accelerate the endothelialization of an electrospun ionomeric polyurethane scaffold. The scaffold was used to physically separate endothelial cells from perivascular cells to prevent their diffuse neo-intimal hyperplasia and spontaneous tubulogenesis, yet enable their paracrine cross-talk to accelerate the integration of the endothelial cells into a temporally stable endothelial lining of a continuous, elongated, and aligned morphology.

Electrospun methacrylated natural/synthetic composite membranes for gingival tissue engineering.

New functional materials for engineering gingival tissue are still in the early stages of development. Materials for such applications must maintain volume and have advantageous mechanical and biological characteristics for tissue regeneration, to be an alternative to autografts, which are the current benchmark of care. In this work, methacrylated gelatin (GelMa) was photocrosslinked with synthetic immunomodulatory methacrylated divinyl urethanes and defined monomers to generate composite scaffolds.

Matrix-Binding, N-Cadherin-Targeting Chimeric Peptide Inhibits Intimal Thickening but Not Endothelial Repair in Balloon-Injured Carotid Arteries.

Background: Treatment of occluded vessels can involve angioplasty, stenting, and bypass grafting, which can be limited by restenosis and thrombosis. Drug-eluting stents attenuate restenosis, but the current drugs used are cytotoxic, causing smooth muscle cell (SMC) and endothelial cell (EC) death that may lead to late thrombosis. N-cadherin is a junctional protein expressed by SMCs, which promotes directional SMC migration contributing to restenosis.

Bioinspired Oligo-Urethane Nanoparticles for Delivering Exogenous C-Type Natriuretic Peptide: Synthetic Biomaterial Nanocarrier Complexes and Their Interactions with Cardiac Myofibroblasts.

In a healthy heart, cells naturally secrete C-type natriuretic peptide (CNP), a cytokine that protects against myofibroblast differentiation of cardiac fibroblasts and extracellular matrix deposition leading to fibrosis. CNP availability during myocardial remodeling is important to prevent cardiac fibrosis, but CNP is limited after an injury because of the loss of cardiomyocytes and the activation of cardiac fibroblasts to myofibroblasts. We hypothesized that the sustained release of exogenous CNP from oligo-urethane nanoparticles (NPs) would reduce differentiation of human cardiac fibroblasts toward a myofibrogenic phenotype.

Less Is More: Developments in Nanotechnology for Antirestenosis Therapies.

Despite recent advancements in vascular disease treatments, thrombosis and poor long-term vessel patency remain significant barriers to effective endovascular intervention. Current balloon angioplasty and stenting techniques effectively restore acute blood flow in occluded vessels but have persistent limitations. Damage to the arterial endothelium caused by injury during catheter tracking triggers neointimal hyperplasia and the release of proinflammatory factors leading to increased risk of thrombosis and restenosis.

Arrhenius-model-based degradable oligourethane hydrogels for controlled growth factor release.

Biodegradable hydrogels are growing in demand to enable the delivery of biomolecules (e.g. growth factors) for regenerative medicine.

Serum- and xeno-free culture of human umbilical cord perivascular cells for pediatric heart valve tissue engineering.

Background: Constructs currently used to repair or replace congenitally diseased pediatric heart valves lack a viable cell population capable of functional adaptation in situ, necessitating repeated surgical intervention. Heart valve tissue engineering (HVTE) can address these limitations by producing functional living tissue in vitro that holds the potential for somatic growth and remodelling upon implantation. However, clinical translation of HVTE strategies requires an appropriate source of autologous cells that can be non-invasively harvested from mesenchymal stem cell (MSC)-rich tissues and cultured under serum- and xeno-free conditions.

In Vivo MRI Tracking of Degradable Polyurethane Hydrogel Degradation In Situ Using a Manganese Porphyrin Contrast Agent.

Background: A noninvasive method to track implanted biomaterials is desirable for real-time monitoring of material interactions with host tissues and assessment of efficacy and safety.

Purpose: To explore quantitative in vivo tracking of polyurethane implants using a manganese porphyrin (MnP) contrast agent containing a covalent binding site for pairing to polymers.

Study Type: Prospective, longitudinal.

A Polypyrrole-Polycarbonate Polyurethane Elastomer Alleviates Cardiac Arrhythmias via Improving Bio-Conductivity.

Myocardial fibrosis, resulting from myocardial infarction (MI), significantly alters cardiac electrophysiological properties. As fibrotic scar tissue forms, its resistance to incoming action potentials increases, leading to cardiac arrhythmia, and eventually sudden cardiac death or heart failure. Biomaterials are gaining increasing attention as an approach for addressing post-MI arrhythmias.

Vascular tissue engineering from human adipose tissue: fundamental phenotype of its resident microvascular endothelial cells and stromal/stem cells.

Adipose tissue is an abundant, accessible, and uniquely dispensable source of cells for vascular tissue engineering. Despite its intrinsic endothelial cells, considerable effort is directed at deriving endothelium from its resident stem and progenitor cells. Here, we investigate the composition of human adipose tissue and characterize the phenotypes of its constituent cells in order to help ascertain their potential utility for vascular tissue engineering.

An efficient and cost-effective purification protocol for Staphylococcus aureus Cas9 nuclease.

Here, we describe a protocol for purifying functional clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) from Staphylococcus aureus within 24 h and over 90% purity. SaCas9 purification begins with immobilized metal affinity chromatography, followed by cation exchange chromatography, and ended with centrifugal concentrators. The simplicity, cost-effectiveness, and reproducibility of such protocols will enable general labs to produce a sizable amount of Cas9 proteins, further accelerating CRISPR research.

Proteases Degrade Dentinal Collagen.

Here, we explored the role of S. mutans’s whole cell and discrete fractions in the degradation of type I collagen and dentinal collagen. Type I collagen gels and human demineralized dentin slabs (DS) were incubated in media alone or with one of the following: overnight (O/N) or newly inoculated (NEW) cultures of S.

Towards the development of biostable dental resin systems - design criteria and constraints beyond ester-free chemistries.

Objective: The objective of this review article is to summarize the current literature on dental resin-based restorative (RBR) materials specifically from the perspective of emerging resin technologies, and to provide researchers with structured design criteria enabling the effective screening of new RBR developments.

Methods: The continued failure of newly introduced RBRs to address biostability without compromising function, over the last decade, are presented as a rationale to support different resin-based concepts. Several developments in the field, aimed at addressing the issues facing modern resin-based systems are summarized and their limitations discussed.

Harnessing conserved signaling and metabolic pathways to enhance the maturation of functional engineered tissues.

The development of induced-pluripotent stem cell (iPSC)-derived cell types offers promise for basic science, drug testing, disease modeling, personalized medicine, and translatable cell therapies across many tissue types. However, in practice many iPSC-derived cells have presented as immature in physiological function, and despite efforts to recapitulate adult maturity, most have yet to meet the necessary benchmarks for the intended tissues. Here, we summarize the available state of knowledge surrounding the physiological mechanisms underlying cell maturation in several key tissues.