The effect of different types of oral or intravenous corticosteroids on capillary blood glucose levels in hospitalized inpatients with and without diabetes.

PURPOSE: This study investigated: (1) the type of corticosteroid associated with the greatest degree of hyperglycemia, assessed using bedside capillary blood glucose monitoring, in hospitalized patients; and (2) the pattern of hyperglycemia throughout the day with the use of each type of corticosteroid. METHODS: This single-center, retrospective study used data from 964 adult inpatients receiving oral or IV corticosteroids. Data on capillary blood glucose concentrations and time taken over 7 days were collected. A mixed model for repeated measures was applied to investigate changes in glucose concentration over time with the use of four different corticosteroids. An autoregressive covariance structure was used to model correlations between repeated measurements. FINDINGS: Across all 7 days, the mean blood glucose concentration was greater with dexamethasone compared to that with hydrocortisone (mean difference, 16.6 mg/dL [95% CI, 8.1-24.8] [0.92 mmol/L (95% CI, 0.45-1.38)]) or prednisolone (mean difference, 20.0 mg/dL [95% CI, 14.2-25.7] [1.11 mmol/L (95% CI, 0.79-1.43)]). The mean blood glucose concentration was greater with methylprednisolone compared to that with hydrocortisone (mean difference, 23.9 mg/dL [95% CI, 11.3-36.4] [1.33 mmol/L (95% CI, 0.63-2.02)]), and with methylprednisolone versus prednisolone (mean difference, 27.4 mg/dL [95% CI, 16.4-38.3] [1.52 mmol/L (95% CI, 0.91-2.13)]). There were no significant differences in the patterns of hyperglycemia at six time points of the day with each type of corticosteroid. IMPLICATIONS: Treatment with oral or IV dexamethasone or methylprednisolone was associated with greater hyperglycemia in comparison to prednisolone and hydrocortisone. More vigorous monitoring and intervention, when necessary, are suggested in adult inpatients receiving corticosteroids, in particular dexamethasone and methylprednisolone.

Injectable nanoclay gels for angiogenesis.

The retention and sustained activity of therapeutic proteins at delivery sites are goals of regenerative medicine. Vascular endothelial growth factor (VEGF) has significant potential in promoting the growth and regeneration of blood vessels but is intrinsically labile. This is exacerbated by the inflammatory microenvironments at sites requiring regeneration. For VEGF to be efficacious, it may require a carrier that stabilises it, protects it from degradation and retains it at the site of interest. In this study, we tested the hypothesis that injectable nanoclay gels comprising Laponite™ XLG (a synthetic hectorite clay) can stabilise VEGF and retain it in the active form for therapeutic delivery. To achieve this, VEGF was incorporated in Laponite gels and its activity tested at a range of concentrations using in vitro cell culture tubulogenesis assays and in vivo angiogenesis assays. We found that VEGF-Laponite gels enhanced tubulogenesis in a dose-dependent manner in vitro. When administered subcutaneously in vivo, Laponite was retained at the injection site for up to a period of three weeks and promoted a 4-fold increase in blood vessel formation compared with that of alginate or vehicle controls as confirmed by CD31 staining. Notably, as compared to alginate, Laponite gels did not release VEGF, indicating a strong interaction between the growth factor and the nanoclay and suggesting that Laponite enhancement of VEGF efficacy is due to its retention at the implantation site for a prolonged period. Our approach provides a robust method for the delivery of bioactive recombinant VEGF without the necessity for complex hydrogel or protein engineering. STATEMENT OF SIGNIFICANCE: In medicine, it is important to deliver drugs to a particular location in the body. Often, however, the drugs are quickly broken down and carried away in the blood before they can exert their effect. In this study, we used a type of synthetic clay, called Laponite™, to preserve a molecule, named VEGF, that stimulates the growth of blood vessels. Previously, we have been able to bind VEGF to the surface of clays, but the clay is not effective when injected or applied as a gel. Herein, we show that we can mix VEGF with the clay and that it strongly stimulates blood vessel growth. We speculate that this would be a useful material for skin wound healing.