Elderberry extract improves molecular markers of endothelial dysfunction linked to atherosclerosis.

Endothelial dysfunction (ED), secondary to diminished nitric oxide (NO) production and oxidative stress, is an early subclinical marker of atherosclerosis. Reduced NO bioavailability enhances the adhesion of monocytes to endothelial cells and promotes atherosclerosis. Elderberry extract (EB) is known to contain high levels of anthocyanins which could exert vascular protective effects.

Thermoresponsive Gels.

Thermoresponsive gelling materials constructed from natural and synthetic polymers can be used to provide triggered action and therefore customised products such as drug delivery and regenerative medicine types as well as for other industries. Some materials give Arrhenius-type viscosity changes based on coil to globule transitions. Others produce more counterintuitive responses to temperature change because of agglomeration induced by enthalpic or entropic drivers.

Synthesis and Identification of FITC-Insulin Conjugates Produced Using Human Insulin and Insulin Analogues for Biomedical Applications.

Human insulin was fluorescently labelled with fluorescein isothiocyanate (FITC) and the conjugate species produced were identified using high performance liquid chromatography and electrospray mass spectroscopy. Mono-labelled FITC-insulin conjugate (A1 or B1) was successfully produced using human insulin at short reaction times (up to 5 h) however the product always contained some unlabelled native human insulin. As the reaction time was increased over 45 h, no unlabelled native human insulin was present and more di-labelled FITC-insulin conjugate (A1B1) was produced than mono-labelled conjugate with the appearance of tri-labelled conjugate (A1B1B29) after 20 h reaction time.

Glucose-sensitive gel rheology of dextran-concanavalin A mixtures suitable for self-regulating insulin delivery.

Aqueous concentrated plain mixtures of dextran and concanavalin A (con A) were examined for their rheological response to glucose for comparison with previously studied partially photopolymerized acrylic derivatives. Non-destructive oscillatory tests were undertaken within the linear viscoelastic range to examine the relationship between the rheometry and the stoichiometry of the interactive materials and to examine rheological parameters as affected by molecular weight, component ratio, temperature and glucose concentrations between 0 and 1% w/w. These simple formulations were studied at 1 and 10 Hz at 0.

UV cross-linked dextran methacrylate--concanavalin A methacrylamide gel materials for self-regulated insulin delivery.

In this study, the successful acrylic derivatization of dextran and concanavalin A (con A) to form dextran methacrylate and con A methacrylamide is shown. These derivatized acrylic monomers are then photopolymerized in the presence of a water soluble photoinitiator Irgacure under various conditions to form covalently bonded glucose-responsive gel materials, which undergo a transformation to sol in the presence of free glucose. Rheological data have revealed that as the degree of substitution for dextran methacrylate is increased, a more elastic material is produced due to the increased covalent linkages.

The effect of degree of acrylic derivatisation on dextran and concanavalin A glucose-responsive materials for closed-loop insulin delivery.

Formulations of dextran methacrylate (dex-MA) and concanavalin A methacrylamide (con A-MA) were photo-polymerized to produce covalently cross-linked glucose-responsive materials for the basis of a closed-loop insulin delivery device. The viscoelastic properties of these polymerised materials were tested rheologically in the non-destructive oscillatory mode within the linear viscoelastic range at glucose concentrations between 0% and 5% w/w. The degree of acrylic substitution was varied for the dex-MA and con A-MA, and as the formulation glucose concentration was raised, a graded decrease in storage modulus, loss modulus and complex viscosity when compared at 1 Hz was observed for each cross-linked material.

Rheological characterisation of dextran-concanavalin A mixtures as a basis for a self-regulated drug delivery device.

The rheological characterisation of glucose sensitive mixtures containing dextran and concanavalin A (con A) with and without glucose, was undertaken using oscillatory rheometry at 20 and 37 degrees C so that comparative data could be gathered in the linear viscoelastic (LVE) range. Measurements for a series of mixtures showed that complex viscosity is a function not only of the con A concentration but of the content and molecular weight of the dextran used. The extent of liquefaction on addition of glucose also depended on these factors.

Glucose-responsive UV polymerised dextran-concanavalin A acrylic derivatised mixtures for closed-loop insulin delivery.

A novel UV polymerised glucose-responsive mixture containing concanavalin A (con A) and dextran was synthesised and characterised as a "smart" biomaterial to form the basis of a closed-loop delivery device. Dextran and con A precursors were modified with acrylic side groups and then UV polymerised to produce covalently bonded mixtures which were examined by FTIR. The viscoelastic properties of these polymerised mixtures containing glucose concentrations between 0% and 5% w/w were also examined using oscillatory rheometry within the linear viscoelastic range across a frequency range of 0.