Tyrosine-derived polycarbonate nerve guidance tubes elicit proregenerative extracellular matrix deposition when used to bridge segmental nerve defects in swine.

Promising biomaterials should be tested in appropriate large animal models that recapitulate human inflammatory and regenerative responses. Previous studies have shown tyrosine-derived polycarbonates (TyrPC) are versatile biomaterials with a wide range of applications across multiple disciplines. The library of TyrPC has been well studied and consists of thousands of polymer compositions with tunable mechanical characteristics and degradation and resorption rates that are useful for nerve guidance tubes (NGTs).

Dual-Component Gelatinous Peptide/Reactive Oligomer Formulations as Conduit Material and Luminal Filler for Peripheral Nerve Regeneration.

Toward the next generation of nerve guidance conduits (NGCs), novel biomaterials and functionalization concepts are required to address clinical demands in peripheral nerve regeneration (PNR). As a biological polymer with bioactive motifs, gelatinous peptides are promising building blocks. In combination with an anhydride-containing oligomer, a dual-component hydrogel system (cGEL) was established.

Effects of Terminal Sterilization on PEG-Based Bioresorbable Polymers Used in Biomedical Applications.

The effects of ethylene oxide (EO), vaporized hydrogen peroxide (VHP), gamma (γ) radiation, and electron-beam (E-beam) on the physiochemical and morphological properties of medical device polymers are investigated. Polymers with ether, carbonate, carboxylic acid, amide and ester functionalities are selected from a family of poly(ethylene glycol) (PEG) containing tyrosine-derived polycarbonates (TyrPCs) to include slow, medium, fast, and ultrafast degrading polymers. Poly(lactic acid) (PLA) is used for comparison.

Biomineralization on enzymatically cross-linked gelatin hydrogels in the absence of dexamethasone.

A mechanical stimulus and chemical induction by dexamethasone have been important factors in dental pulp stem cell (DPSC) differentiation and biomineralization. We have demonstrated that the enzymatically crosslinked gelatin hydrogels are extremely effective substrates for DPSC differentiation towards odontoblasts. DPSCs were seeded on the crosslinked hard (∼8 kPa) and soft (∼0.

Deformation gradients imprint the direction and speed of en masse fibroblast migration for fast healing.

En masse cell migration is more relevant compared with single-cell migration in physiological processes of tissue formation, such as embryogenesis, morphogenesis, and wound healing. In these situations, cells are influenced by the proximity of other cells including interactions facilitated by substrate mechanics. Here, we found that when fibroblasts migrated en masse over a hydrogel, they established a well-defined deformation field by traction forces and migrated along a trajectory defined by field gradients.

An in vivo analysis of the effect and duration of treatment with botulinum toxin type A using digital image speckle correlation.

Background: Use of Botulinum toxin type A (BTX-A) for facial wrinkles is well-documented, but current methods of subjective evaluation by clinicians and patients fail to objectively quantify the magnitude and duration of facial muscle paralysis.

Objective: (a) Determine the locus of facial muscular tension; (b) Quantify and monitor muscular paralysis and subsequent return; (c) Continuously correlate the appearance of wrinkles and muscular tension using non-invasive digital image speckle correlation (DISC) to measure treatment efficacy; (d) Corroborate objective data with existing rating scales (subject global assessment and facial lines outcome-11).

Methods: Two sequential images of slight facial motion (frowning, raising eyebrows) are taken with a camera for n = 6 patients pre- and post-treatment at different time points up to 24 weeks.

Comparison of native porcine skin and a dermal substitute using tensiometry and digital image speckle correlation.

Dermal substitutes are currently used in plastic surgery to cover various soft tissue defects caused by trauma, burns, or ablative cancer surgery. Little information is available on the biomechanical properties of these dermal substitutes after adequate incorporation as compared to normal skin. Determining parameters such as tensile strength in these skin substitutes will help us further understand their wound healing properties and potential in developing artificial tissue constructs.

Synthesis of 2-oxo/thioxooctahydroquinazolin-5-one derivatives and their evaluation as anticancer agents.

An environment friendly method for the synthesis of 2-oxo/thioxooctahydroquinazolin-5-one derivatives has been devised using Ceric ammonium nitrate (CAN) as catalyst and polyethylene glycol (PEG) as solvent. The cytotoxic effect of these compounds was studied on U87 human glioma cells, compounds 4c, 4d and 4e are found to exhibit excellent activity at a concentration as low as 0.06 µg/ml.