Can a mock medication-taking learning activity enable pharmacy students to experience the range of barriers and facilitators to medication adherence? An analysis informed by the Theoretical Domains Framework and COM-B model.

Background: Pharmacy professionals are well-placed to provide medication adherence support to patients. The Capability, Opportunity, Motivation-Behaviour (COM-B) and Theoretical Domains Framework (TDF) are two complementary models previously applied to medication-taking behaviour. Understanding the patient-specific barriers and facilitators to adherence using psychological frameworks from the early stages of pharmacy education enables the design and delivery of effective interventions. Objectives: To examine whether a novel 'mock medicine' learning activity enabled students to experience the range of barriers and facilitators to medication adherence using the COM-B and TDF. Methods: A mock medicine activity was conducted with students at pharmacy schools in three universities in the UK, Norway, and Australia over one week. Percentage adherence was calculated for five dosing regimens; theoretical framework analysis was applied to map reflective statements from student logs to COM-B and TDF. Results: A total of 349 students (52.6%) returned completed logs, with high overall mean adherence (83.5%, range 0-100%). Analysis of the 277 (79.4%) students who provided reflective statements included barriers and facilitators that mapped onto one (9%), two (29%) or all three (62%) of the COM-B components and all fourteen TDF domains (overall mean = 4.04; Uni 1 = 3.72; Uni 2 = 4.50; Uni 3 = 4.38; range 1-8). Most frequently mapped domains were 'Environmental context and resources' (n = 199; 72%), 'Skills' (n = 186; 67%), 'Memory, attention and decision-making' (184; 66%) and 'Beliefs about capabilities' (n = 175; 63%). Conclusions: This is the first study to utilise both COM-B and TDF to analyse a proxy measure of medication adherence in pharmacy education. Data mapping demonstrated that students experienced similar issues to patients when prescribed a short course of medication. Importantly, all the factors influencing medication-taking reported by students were captured by these two psychological frameworks. Future educational strategies will involve students in the mapping exercise to gain hands-on experience of using these psychological constructs in practice.

A pharmacological characterization of GABA, THIP and DS2 at binary α4ß3 and ß3δ receptors: GABA activates ß3δ receptors via the ß3(+)δ(-) interface.

There is growing evidence that GABA (γ-aminobutyric acid) can activate GABAA receptors (GABAARs) in the absence of an α subunit. In this study, we compared the pharmacology of homomeric and binary α4, ß3 or δ subunits with ternary α4ß3δ to identify subunit interfaces that contribute to the pharmacology of GABA, THIP, and DS2, and the antagonists, Zn(2+), gabazine and bicuculline. ß3δ receptors form functional GABA-gated channels when expressed in Xenopus oocytes with a pharmacology that differs to homomeric ß3, binary α4ß3 and ternary α4ß3δ receptors. GABA had similar potency at α4ß3 and ß3δ receptors (25µM and 26µM, respectively) but differed at α4ß3δ receptors where GABA exhibited a biphasic concentration-response (EC50 (1)=12.6nM; EC50 (2)=6.3µM). THIP activated ß3δ receptors (EC50=456µM) but was a more potent activator of α4ß3 (EC50=27µM) and α4ß3δ receptors (EC50 (1)=27.5nM; EC50 (2)=29.5µΜ), indicating that the α4 subunit significantly contribute to its potency. The δ-preferring modulator, DS2 had marginal or no effect at ß3δ and α4ß3 receptors, indicating a role for both the α4 and δ subunits for its potency. Gabazine inhibited GABA-elicited currents at ß3δ receptors whereas bicuculline activated these receptors. Mutational analysis verified that GABA binds to the ß3(+)δ(-) interface formed by the ß3 and δ subunits. In conclusion, evaluating agents against binary GABAARs such as ß3δ and α4ß3 receptors enables identification of interfaces that may contribute to the pharmacology of the more complex ternary α4ß3δ receptors.

A hydrophobic area of the GABA ρ1 receptor containing phenylalanine 124 influences both receptor activation and deactivation.

Experimental evidence suggests that GABA ρ1 receptors are potential therapeutic targets for the treatment of a range of neurological conditions, including anxiety and sleep disorders. Homology modelling of the GABA ρ1 extracellular N-terminal domain has revealed a novel hydrophobic area that extends beyond, but not including the GABA-binding site. Phenylalanine 124 (F124) is predicted to be involved in maintaining the structural integrity of the orthosteric-binding site. We have assessed the activity of a series of GABA ρ1 receptors that incorporate a mutation at F124. Wild-type and mutant human GABA ρ1 subunits were expressed in Xenopus laevis oocytes and AD293 cells, and the pharmacology and kinetic properties of the receptors were measured using electrophysiological analysis. Mutation of F124 had minimal effect on receptor pharmacology. However, the rate of deactivation was significantly increased compared to wild type. This study provides further information about the role of residues within a novel hydrophobic area of the GABA ρ1 receptor. This knowledge can help future studies into the design of potent and subtype-selective ligands with therapeutic value.

Provision of opioid substitution therapy services in Australian pharmacies.

Opioid dependence, despite being the subject of significant public funding, remains a costly burden to Australian society in human and economic terms. The most cost-effective public health strategy for managing opioid dependence is opioid substitution therapy (OST), primarily through the use of methadone or buprenorphine. Supervised dispensing of OST from specialist clinics and community pharmacies plays a crucial role in enhancing compliance, monitoring treatment and reducing diversion. Australia, compared with other countries in the world, ranks very high in illicit opioid use; hence there is a great demand for OST.The utilisation of community pharmacies for stable patients has many advantages. For public clinics, patient transfer to community pharmacies relieves workload and costs, and increases capacity for new OST patients. From a patient's perspective, dosing at a pharmacy is more flexible and generally more preferable. Pharmacists stand to gain clientele, profit and receive small incentives from state governments in Australia, for their services. Yet, many "unmet needs" exist and there is a high demand for more involvement in OST service provision in community pharmacy in Australia.In the UK there has been a steady increase in community pharmacy provision of OST, and pharmacists appear ready to provide further healthcare services to these patients.The role of pharmacy in some countries in Europe, such as Germany, is less prominent due to their approach to harm minimisation and the complex, variable nature of OST provision across the European Union (EU). The provision of OST by pharmacists in the USA on the other hand is of lesser frequency as the healthcare system in the USA encourages detoxification clinics to handle cases of illicit drug addiction.At a time when harm minimisation strategies constitute a topic of considerable political and public interest, it is important to understand the scope and variability of pharmacy involvement in drug policy in Australia. Hence, this review highlights the role of pharmacists in OST and explores the scope for expanding this role in the future.

The enzymatic synthesis of antiviral agents.

The majority of potential antiviral agents which are currently undergoing clinical trials are inhibitors of the replication of nucleic acids. The most common class of these inhibitors are nucleoside analogues and the elucidation of synthetic routes to these compounds has been of interest for many years as many are anticancer agents. One synthetic development has been the application of bio-transformations to nucleoside syntheses. This topic has been reviewed recently (Shirae et al., 1991) but this review is not widely available. In the present review, the application of biotechnology to the synthesis of antiviral agents including those which are not nucleoside analogues will be discussed. Enzymatic syntheses of nucleosides can be simpler and quicker than syntheses carried out by chemical methods. The most useful enzymes are those found in catabolic pathways. Nucleoside phosphorylases and N-deoxyribosyltransferases have both been widely used for nucleoside synthesis catalysing the transfer of sugar residues from a donor nucleoside to a heterocyclic base. Enzymatic methods have also been applied to the resolution of racemic mixtures and adenosine deaminase is a convenient catalyst for the hydrolysis of amino groups on purines and purine analogues. Regioselective deprotection of nucleoside esters has been achieved with lipases and these enzymes have also been applied to the synthesis of esters of sugar-like alkaloids. The latter have potential as inhibitors of the replication of HIV. Esterases have also been used in combined chemical and enzymatic syntheses of organophosphorus antiviral agents.

Synthesis and activity of a potent N-methyl-D-aspartic acid agonist, trans-1-aminocyclobutane-1,3-dicarboxylic acid, and related phosphonic and carboxylic acids.

We report the synthesis of a series of 3-carboxy-, 3-(carboxymethyl)-, 3-(omega-phosphonoalkyl)-1-aminocyclobutane-1-carboxylic acids for evaluation as agonists or antagonists of neurotransmission at excitatory amino acid receptors, particularly N-methyl-D-aspartic acid (NMDA) receptors. The compounds were evaluated as agonists on their ability to depolarize the rat brain cortical wedge preparation or as antagonist of the actions of the selective agonists NMDA, quisqualic acid, and kainic acid. The chain-elongated glutamate derivatives with potential antagonist activity proved to be weak and frequently nonselective antagonists in this assay. The most noteworthy result was that trans isomer 7b was a very potent agonist, approximately 20 times more active than NMDA at NMDA receptors, while the cis isomer was 1/3 as potent as NMDA.