Barriers and facilitators to accessing insulin pump therapy by adults with type 1 diabetes mellitus:a qualitative study

AIMS: Uptake of continuous subcutaneous insulin infusion (CSII) by people with diabetes (PwD) in Ireland is low and exhibits regional variation. This study explores barriers and facilitators to accessing CSII by adults with Type 1 diabetes mellitus. RESEARCH DESIGN AND METHODS: A qualitative study employing focus groups with adults with Type 1 diabetes mellitus (n = 26) and semi-structured interviews with health care professionals (HCP) and other key stakeholders (n = 21) was conducted. Reflexive thematic analysis was used to analyze data, using NVivo. RESULTS: Four main themes comprising barriers to or facilitators of CSII uptake were identified. These included: (1) awareness of CSII and its benefits, (2) the structure of diabetes services, (3) the capacity of the diabetes service to deliver the CSII service, and (4) the impact of individuals' attitudes and personal characteristics-both PwD, and HCP. Each of these themes was associated with a number of categories, of which 18 were identified and explored. If the structure of the health-service is insufficient and capacity is poor (e.g., under-resourced clinics), CSII uptake appears to be impacted by individuals': interest, attitude, willingness and motivation, which may intensify the regional inequality in accessing CSII. CONCLUSIONS: This study identified factors that contribute to gaps in the delivery of diabetes care that policy-makers may use to improve access to CSII for adult PwD

The acute effects of daily nicotine intake on heart rate--a toxicokinetic and toxicodynamic modelling study.

Abstract Joint physiologically-based toxicokinetic and toxicodynamic (PBTK/TD) modelling was applied to simulate concentration–time profiles of nicotine, a well-known stimulant, in the human body following single and repeated dosing. Both kinetic and dynamic models were first calibrated by using in vivo literature data for the Caucasian population. The models were then used to estimate the blood and liver concentrations of nicotine in terms of the Area Under Curve (AUC) and the peak concentration (Cmax) for selected exposure scenarios based on inhalation (cigarette smoking), oral intake (nicotine lozenges) and dermal absorption (nicotine patches). The model simulations indicated that whereas frequent cigarette smoking gives rise to high AUC and Cmax in blood, the use of nicotine-rich dermal patches leads to high AUC and Cmax in the liver. Venous blood concentrations were used to estimate one of the most common acute effects, mean heart rate, both at rest and during exercise. These estimations showed that cigarette smoking causes a high peak heart rate, whereas dermal absorption causes a high mean heart rate over 48 h. This study illustrates the potential of using PBTK/TD modelling in the safety assessment of nicotine-containing products

In vitro-to-in vivo correlation of the skin penetration, liver clearance and hepatotoxicity of caffeine

Abstract This work illustrates the use of Physiologically-Based Toxicokinetic (PBTK) modelling for the healthy Caucasian population in in vitro -to- in vivo correlation of kinetic measures of caffeine skin penetration and liver clearance (based on literature experiments), as well as dose metrics of caffeine-induced measured HepaRG toxicity. We applied a simple correlation factor to quantify the in vitro and in vivo differences in the amount of caffeine permeated through the skin and concentration-time profiles of caffeine in the liver. We developed a multi-scale computational approach by linking the PBTK model with a Virtual Cell-Based Assay to relate an external oral and dermal dose with the measured in vitro HepaRG cell viability. The results revealed higher in vivo skin permeation profiles than those determined in vitro using identical exposure conditions. Liver clearance of caffeine derived from in vitro metabolism rates was found to be much slower than the optimised in vivo clearance with respect to caffeine plasma concentrations. Finally, HepaRG cell viability was shown to remain almost unchanged for external caffeine doses of 5–400 mg for both oral and dermal absorption routes. We modelled single exposure to caffeine only

Thermal Decomposition Pathways of ZnxFe3- xO4Nanoparticles in Different Atmospheres

This article shows how initial composition and thermal treatment of nonstoichiometric zinc ferrite nanoparticles (nZFN) can be chosen to adjust the structure and cation distribution and enhance magnetism in the resulting nanoscale material. It also provides insight into new prospects regarding the production and design of nanoscale materials. Investigations were conducted before and after heating of nZFN in an inert atmosphere and a vacuum up to temperature of 1170 °C. Annealing leads to partial reduction of Fe ions, enhanced magnetism, and an increase in the size of the particles independent of the atmosphere. Use of the inert atmosphere delivers a solid solution of magnetite and zinc ferrite with a reduced Zn content in the structure as a result of sublimation of newly formed ZnO and reduction of Fe, and it favors crystallization. A preference for normal-spinel phase and enhancement of magnetic saturation from 20 Am2/kg up to 101 Am2/kg was observed. Vacuum annealing with high probability produces ZnO, Fe3O4, and Fe2O3 multiphase system with signs of amorphization, mainly on the surface. A large fraction of Fe ions is reduced and the volume ratio of Fe3O4 to Fe2O3 increases with heating time. The final solid product from a complete decomposition of ZFN is magnetite

Effect of Fasciola hepatica proteins on the functioning of rat hepatocytes

Fasciolosis is a hepatic parasitic infection that affects many mammal species and creates a great economic and veterinary problem. Molecular mechanisms of parasite–hepatocyte interactions have not been precisely characterized yet. Therefore, the aim of the study was to investigate alterations in the metabolic activity of rat liver cells exposed to Fasciola hepatica somatic proteins. Hepatocytes were incubated with 0–1 mg/ml of fluke's somatic proteins for various periods of time. Afterward, changes in hepatocytes metabolic activity were determined with MTT and enzyme leakage tests. Hepatocytes' capacity to synthesize albumin was also investigated. It was observed that protein concentration, as well as longevity of their action, influenced metabolic activity of rat liver cells. Diminution of hepatocytes survival rate, an increase in enzyme leakage and altered synthetic capacity after treatment with parasite's proteins were reported. It is concluded that somatic proteins of F. hepatica may play an important role in liver cell damaging

Laccase-catalyzed controlled radical polymerization of N-vinylimidazole

Laccase from Trametes versicolor is a multi-copper-containing oxidoreductase which was found to catalyze the polymerization of N-vinylimidazole under conditions of atom transfer radical polymerization (ATRP) in aqueous solution (pH 4, 100 mM acetate buffer) at ambient temperature by using sodium ascorbate as a reducing agent. The reaction followed first order kinetics and resulted in polymers with controlled number-average molecular weights (between 1660 and 9970 g mol-1) and relatively narrow, monomodal molecular weight distributions (D between 1.27 and 1.56) according to gel permeation chromatography. Purified polymers were also analyzed by mass spectrometry which revealed a D of 1.07. The enzyme could be separated quantitatively from the polymer, lowering the metal content of the purified polymers below the detection limit of ICP-OES of 9 ppb. The enzyme retained its polymerization activity for more than eight hours, but formed electrostatic complexes with the polymer and underwent conformational changes at the beginning of the reaction. Biocatalytic controlled radical polymerization allows the synthesis of poly(N-vinylimidazole) with a well-defined molecular weight. Such polymers will be useful building blocks in many applications, such as drug- and gene-delivery, fuel cell membranes and polyionic liquids