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Background: Corticosteroids raise blood glucose concentrations; however, it remains unknown which form of administration, oral or intravenous, is associated with the greatest degree of blood glucose rise in hospitalised patients. Furthermore, it is not known whether the pattern of the associated hyperglycaemia throughout the day differs depending on the route of administration., Methods: This was a single centre retrospective study of 384 adult inpatients receiving oral or intravenous hydrocortisone and dexamethasone. Data on capillary glucose concentrations and time taken over 7 days were collected. A mixed model for repeated measures was applied to compare changes in glucose concentration over time for oral and intravenous corticosteroids. An auto-regressive covariance structure was employed to model correlations between repeated measurements. This was adjusted for age, sex, pre-admission diabetes, and/or pre-admission corticosteroid status., Results: No significant difference was found between oral and intravenous hydrocortisone on day 1 or across all 7 days (mean difference 0.17 mmol/L (-1.39, 1.75), p = 0.827, and mean difference 0.20 mmol/L (-0.61, 1.01), p = 0.639 respectively). There were no differences in mean glucose concentrations between those on oral or intravenous dexamethasone on day 1 or across all 7 days (mean difference 0.41 mmol/L (-0.55, 1.38), p = 0.404 and mean difference -0.09 mmol/L (-1.05,0.87), p = 0.855, respectively)., Conclusion: This study found that oral and intravenous administration of hydrocortisone and dexamethasone do not have a significantly differing impact on blood glucose levels. Capillary glucose monitoring is strongly recommended in all individuals who are on either oral or intravenous corticosteroids., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

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., Competing Interests: Declaration of Competing Interest The authors have indicated that they have no conflicts of interest with regard to the content of this article., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Vascular endothelial growth factor receptors (VEGFRs) are part of the evolutionarily conserved VEGF signalling pathways that regulate the development and maintenance of the body's cardiovascular and lymphovascular systems. VEGFR3, encoded by the FLT4 gene, has an indispensable and well-characterized function in development and establishment of the lymphatic system. Autosomal dominant VEGFR3 mutations, that prevent the receptor functioning as a homodimer, cause one of the major forms of hereditary primary lymphoedema; Milroy disease. Recently, we and others have shown that FLT4 variants, distinct to those observed in Milroy disease cases, predispose individuals to Tetralogy of Fallot, the most common cyanotic congenital heart disease, demonstrating a novel function for VEGFR3 in early cardiac development. Here, we examine the familiar and emerging roles of VEGFR3 in the development of both lymphovascular and cardiovascular systems, respectively, compare how distinct genetic variants in FLT4 lead to two disparate human conditions, and highlight the research still required to fully understand this multifaceted receptor., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Cardiology.)

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., (Copyright © 2019. Published by Elsevier Ltd.)

Competing Interests: Competing interests: None declared.

Angiogenesis is driven by the coordinated collective branching of specialized leading "tip" and trailing "stalk" endothelial cells (ECs). While Notch-regulated negative feedback suppresses excessive tip selection, roles for positive feedback in EC identity decisions remain unexplored. Here, by integrating computational modeling with in vivo experimentation, we reveal that positive feedback critically modulates the magnitude, timing, and robustness of angiogenic responses. In silico modeling predicts that positive-feedback-mediated amplification of VEGF signaling generates an ultrasensitive bistable switch that underpins quick and robust tip-stalk decisions. In agreement, we define a positive-feedback loop exhibiting these properties in vivo, whereby Vegf-induced expression of the atypical tetraspanin, tm4sf18, amplifies Vegf signaling to dictate the speed and robustness of EC selection for angiogenesis. Consequently, tm4sf18 mutant zebrafish select fewer motile ECs and exhibit stunted hypocellular vessels with unstable tip identity that is severely perturbed by even subtle Vegfr attenuation. Hence, positive feedback spatiotemporally shapes the angiogenic switch to ultimately modulate vascular network topology., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Rationale: Familial recurrence studies provide strong evidence for a genetic component to the predisposition to sporadic, nonsyndromic Tetralogy of Fallot (TOF), the most common cyanotic congenital heart disease phenotype. Rare genetic variants have been identified as important contributors to the risk of congenital heart disease, but relatively small numbers of TOF cases have been studied to date., Objective: We used whole exome sequencing to assess the prevalence of unique, deleterious variants in the largest cohort of nonsyndromic TOF patients reported to date., Methods and Results: Eight hundred twenty-nine TOF patients underwent whole exome sequencing. The presence of unique, deleterious variants was determined; defined by their absence in the Genome Aggregation Database and a scaled combined annotation-dependent depletion score of ≥20. The clustering of variants in 2 genes, NOTCH1 and FLT4, surpassed thresholds for genome-wide significance (assigned as P<5×10 -8 ) after correction for multiple comparisons. NOTCH1 was most frequently found to harbor unique, deleterious variants. Thirty-one changes were observed in 37 probands (4.5%; 95% CI, 3.2%-6.1%) and included 7 loss-of-function variants 22 missense variants and 2 in-frame indels. Sanger sequencing of the unaffected parents of 7 cases identified 5 de novo variants. Three NOTCH1 variants (p.G200R, p.C607Y, and p.N1875S) were subjected to functional evaluation, and 2 showed a reduction in Jagged1-induced NOTCH signaling. FLT4 variants were found in 2.4% (95% CI, 1.6%-3.8%) of TOF patients, with 21 patients harboring 22 unique, deleterious variants. The variants identified were distinct to those that cause the congenital lymphoedema syndrome Milroy disease. In addition to NOTCH1, FLT4 and the well-established TOF gene, TBX1, we identified potential association with variants in several other candidates, including RYR1, ZFPM1, CAMTA2, DLX6, and PCM1., Conclusions: The NOTCH1 locus is the most frequent site of genetic variants predisposing to nonsyndromic TOF, followed by FLT4. Together, variants in these genes are found in almost 7% of TOF patients.

The asymmetric division of stem or progenitor cells generates daughters with distinct fates and regulates cell diversity during tissue morphogenesis. However, roles for asymmetric division in other more dynamic morphogenetic processes, such as cell migration, have not previously been described. Here we combine zebrafish in vivo experimental and computational approaches to reveal that heterogeneity introduced by asymmetric division generates multicellular polarity that drives coordinated collective cell migration in angiogenesis. We find that asymmetric positioning of the mitotic spindle during endothelial tip cell division generates daughters of distinct size with discrete 'tip' or 'stalk' thresholds of pro-migratory Vegfr signalling. Consequently, post-mitotic Vegfr asymmetry drives Dll4/Notch-independent self-organization of daughters into leading tip or trailing stalk cells, and disruption of asymmetry randomizes daughter tip/stalk selection. Thus, asymmetric division seamlessly integrates cell proliferation with collective migration, and, as such, may facilitate growth of other collectively migrating tissues during development, regeneration and cancer invasion.

An in vitro demineralization model has been developed and used to examine the effect of various fluoride treatments on early enamel demineralization. The effect of fluoride treatments on the calcium demineralization rate of enamel was studied by analyzing the amount of calcium which demineralized from teeth into solution when the teeth were exposed to weak acid solutions. Continuous (72 h total) exposure of enamel to very low levels of fluoride, 0.014 ppm, was observed to have a protective effect against demineralization, as was intermittent exposure to higher levels of fluoride delivered from solution and from dentifrices for shorter periods of time (40 min total). This work suggests that the residual salivary fluoride concentrations reported to be reached by water fluoridation (0.016 ppm) or brushing with a fluoride-containing dentifrice (0.014 ppm) give a level of fluoride in saliva which may give some protection to the dental enamel from demineralization.

The electrochemistry of the redox proteins, cytochrome c, cytochrome b5, plastocyanin and ferredoxin at modified gold electrodes has been examined on the basis that electron transfer takes place at electroactive sites which are microscopic in size. Using this model, it is now proposed that electrochemistry of these proteins occurs at suitably modified sites with fast rates at potentials near the standard redox potential. The microscopic model implies that redox proteins and enzymes take part in fast electron transfer at specific sites on the electrode, other sites being completely ineffective. This form of molecular recognition, i.e. the ability to discriminate between the different sites on an electrode surface, mimics homogeneous redox reactions wherein redox active proteins 'recognize' their biological partners in a very specific sense. Previously, protein electrochemistry has been interpreted via use of a macroscopic model in which the proteins are transported to the electrode surface by linear diffusion followed by quasi-reversible or irreversible electron transfer to the electrode surface. The microscopic model, which assumes that the movement of the protein occurs predominantly by radial diffusion to very small sites, would appear to explain the data more satisfactorily and be consistent with biologically important, homogeneous redox reactions which are known to be fast.