Asthma management by New Zealand pharmacists: a pharmaceutical care demonstration project

Background: Pharmaceutical care services became recognized in New Zealand in the mid-1990s, albeit with limited evidence of the acceptability and effectiveness of the model. An asthma-specific pharmaceutical care service was trialled in southern New Zealand, based on a 'problem-action-outcome' method, with pharmacists adopting a patient-centred, outcome-focused approach with multidisciplinary consultation. Objective: To report on the implementation and outcomes of a specialist asthma service offered by community pharmacists. Design: Pharmacists in five pharmacies, servicing predominantly rural, established clientele, received training in the asthma service and research documentation. Ten patients per pharmacy were recruited in each year (years 1 and 2) of the study. The patients were entered into the study in cohorts of five per pharmacy twice yearly, with year 2 mirroring year 1. The phase-in design minimized the impact on the pharmacists. The patients acted as their own controls. All patients received individualized care and had approximately monthly consultations with the pharmacist, with clinical and quality of life (QoL) monitoring. Results: A total of 100 patients were recruited. On average, 4.3 medication-related problems were identified per patient; two-thirds of them were compliance-related. The most common interventions were revision of patients' asthma action plans, referral and medication counselling. Clinical outcomes included reduced bronchodilator use and improved symptom control in around two-thirds of patients. Asthma-specific QoL changes were more positive and correlated well with clinical indicators. Conclusion: Further research is warranted to integrate this service into daily practice. Clinical outcomes were generally positive and supported by QoL indicators. Characteristics of New Zealand practice and this sample of pharmacies may limit the generalizability of these findings.

Physical enhancement of transdermal drug application: is delivery technology keeping up with pharmaceutical development?

Advances in molecular biology have given us a wide range of protein and peptide-based drugs that are unsuitable for oral delivery because of their high degree of first-pass metabolism. Though parenteral delivery is the obvious answer, for the successful development of commercial chronic and self-administration usage formulations it is not the ideal choice. Transdermal delivery is emerging as the biggest application target for these agents, however, the skin is extremely efficient at keeping out such large molecular weight compounds and therapeutic levels are never going to be realistically achieved by passive absorption. Physical enhancement mechanisms including: iontophoresis, electroporation, ultrasound, photomechanical waves, microneedles and jet-propelled particles are emerging as solutions to this topical delivery dilemma. Adding proteins and peptides to the list of other large molecular weight drugs with insufficient passive transdermal fluxes to be therapeutically useful, we have a collection of pharmacological agents waiting for efficient delivery methods to be introduced. This article reviews the current state of physical transdermal delivery technology, assesses the pros and cons of each technique and summarises the evidence-base of their drug delivery capabilities.

Solution structure of the cyclotide palicourein: Implications for the development of a pharmaceutical framework

The cyclotides are a family of disulfide-rich proteins from plants. They have the characteristic structural features of a circular protein backbone and a knotted arrangement of disulfide bonds. Structural and biochemical studies of the cyclotides suggest that their unique physiological stability can be loaned to bioactive peptide fragments for pharmaceutical and agricultural development. In particular, the cyclotides incorporate a number of solvent-exposed loops that are potentially suitable for epitope grafting applications. Here, we determine the structure of the largest known cyclotide, palicourein, which has an atypical size and composition within one of the surface-exposed loops. The structural data show that an increase in size of a palicourein loop does not perturb the core fold, to which the thermodynamic and chemical stability has been attributed. The cyclotide core fold, thus, can in principle be used as a framework for the development of useful pharmaceutical and agricultural bioactivities.

The effects of parabens on the mechanosensitive channels of E. coli

Parabens are alkyl esters of p-hydroxybenzoic acid used as preservatives in a wide range of food, pharmaceutical, and cosmetic products (Soni et al. Food Chem. Toxicol. 39:513-532, 2001). Despite their common use for over 50 years, their mechanism of action is still unclear. In this study we examined the effects of ethyl and propyl paraben, on gating of the E. coli mechanosensitive channel of large conductance (MscL) reconstituted into azolectin liposomes. We found that propyl and ethyl paraben spontaneously activate MscL. Moreover, the addition of propyl paraben caused an increase in MscL activity and the lowering Of P-1/2, the pressure at which the MscL was opened 50% of the time, the AGO, the free energy required to open the MscL, and the parameter a, which describes the channel sensitivity to pressure. In addition, in silico studies showed that propyl paraben binds to the channel gate of the MscL. The mechanosensitive channel of small conductance was also found to be spontaneously activated by parabens. In summary, our study indicates that one of the previously unidentified mechanisms of action of parabens as antimicrobial agents is via an interaction with the mechanosensitive channels to upset the osmotic gradients in bacteria.