The need for medicines support to be person centred is well recognised. Studies have highlighted sub-optimal adherence to medicines by stroke survivors even though secondary prevention is critical to preventing a repeat event. Community pharmacists are currently not integrated into the stroke care pathway but have been directed to provide medicines support to vulnerable groups of patients, including stroke survivors. This three-phase mixed-methods study explored how person-centred care is delivered and can be optimally supported within a medicine-focused consultation between stroke survivors and community pharmacists. Guided by Interpretative Interactionism, the first phase involved semi-structured interviews with 15 stroke survivors and 16 community pharmacists. Data were thematically analysed (NVivo 10) and then mapped to the principles of person-centred care (de Silva 2014). Phase two involved the development, piloting and dissemination of a questionnaire to explore stroke survivors' experience of and perceived need for medicine support, their use of pharmacy services and their self-reported adherence. Data received from 208 completed questionnaires were evaluated (SPSSV24): online n=79 (38%)/postal n=129 (36% response rate). Phase three involved the development of a consultation tool from results from earlier phases and the literature, and preliminary evaluation of this tool from feedback received from community pharmacists who had participated in phase one interviews (n=11/69%). This study highlights that stroke survivors often have unmet medicine support needs that could be addressed by a pharmacist. However, only one quarter of stroke survivors had received the medicine consultation services currently offered by pharmacists and many were unaware of these services. Limited contact with their pharmacist was attributed to the sequelae of their stroke and difficulties accessing community pharmacies. The need to improve pharmacists' approach to consultations with stroke survivors, and specifically to identify their individual needs, was identified. Pharmacists provided positive feedback on the consultation tool developed. This thesis contributes to supporting community pharmacists' delivery of person-centred stroke consultations through the development of a consultation tool, although further evaluation of this is required. The availability of medicine support services offered by community pharmacists within the current NHS contract needs to be promoted. However, changes in current practice are necessary. These should include the integration of pharmacists into the multi-disciplinary care pathway for stroke, together with provision of more domiciliary-based pharmacy services.

The new branch of medicine, nanomedicine, implies the use of engineered devices and nanostructures in order to accelerate the knowledge of biomolecular-biological processes, to improve the efficiency of disease therapeutics and to develop novel diagnostic techniques. In the present work, three aspects related to the use of nanoparticles (NPs) in biomedical applications have been investigated. Overall, NPs can be applied for in vivo and in vitro bio-applications and the results achieved are strongly related with the stability of the material in suspension and in biological fluids. In particular, silica nanoparticles (SiNPs) have been synthesised and used for (I) the development of a probe for the fluorescent detection of bacteria (II) as carriers in oral drug delivery and (III) they have been used as proxy for the evaluation of a novel storage method to retain long-term colloidal stability of NPs suspensions. I) Addressing the need of cheap devices capable of detecting bacteria, here we investigated the use of NPs for bacterial detection. An "on-off" fluorescent substrate was firstly synthesised by glycosylic bond formation between a carbohydrate and a switchable fluorophore and its efficiency in detecting the presence of microorganisms was evaluated. 'Nanoprobes' were then developed by functionalising the surface of particles (silica, gold nanoparticles and streptavidin-coated magnetic nanoparticle) with the synthesised substrates. The nanoprobes successfully detected bacteria as proof-of-concept and the developed detection strategy provides a platform upon which further improvements in bacterial detection can be made in the future. II) The second research challenge proposes to take advantage of the pH-sensitivity of SiNPs for the design of drug delivery systems suitable for oral administration. SiNPs were synthesised from tetraethyl orthosilicate (TEOS) and ethyl triethoxysilane (ETEOS) using different ratios of the two precursors. The degradation and model-drug release profiles from the NPs were analysed in the context of oral drug delivery. The NPs were exposed to pH's found in the GI tract and indicated that silica NPs can be suitable carriers as they avoided degradation at pH4 found in the fed stomach and began releasing model-drug in small intestine-like pH's (pH6 and pH7.4). It was also shown that covalently binding model-drug (fluorescein isothiocyante) inside the NPs led to greater molecule retention inside the NPs over time compared to those physically entrapped in the particle matrix (fluorescein sodium salt and methylene blue). In addition, the dissolution of the NPs was also proved to proceed via different mechanisms depending on the TEOS:ETOS formulation, which presents future avenues for drug release studies. III) Finally, we addressed the colloidal stability issues that are still limiting the real application of nanoparticles on the market. With this aim, a novel approach to stabilise nanoparticles during storage was explored. By trapping the NPs in the matrix of a reversible hydrogel we showed that the physico-chemical proprieties are better maintained over time compared to NPs stored in solution. In vitro and ex ovo assays proved that the gel-NPs were non-toxic and suggested that NPs stored in gel can be used for biological experimentations without require further purification steps. Studies of gel strength allow considering the proposed method as a promising alternative to the storage techniques currently available, such as surface-coating or lyophilisation methods. The evaluation of the efficiency and versatility of the proposed storage method has been recently published. Overall the applicability of NPs as platform for bacterial detection, for oral drug delivery have been evaluated and a novel versatile and efficient approach to stabilise NPs in suspension during storage have been developed and evaluated. The findings will hopefully contribute positively to the field of nanomedicine and helping the translation of materials from the laboratory bench to the market.

Natural products have played a key role in drug discovery and are still a prolific source of novel lead compounds or pharmacophores for medicinal chemistry. Pharmacological activity and druggability are two indispensable components advancing natural products from leads to drugs. Although naturally active substances are usually good lead compounds, most of them can hardly satisfy the demands for druggability. Hence, these structural phenotypes have to be modified and optimized to overcome existing deficiencies and shortcomings. Combretastatin A-4 (CA-4) 1 belongs to a class of natural stilbene derivatives isolated from the bark of the South African bush willow tree combretum caffrum that displays anticancer activity by binding to the tubulin colchicine-binding site. Polyunsaturated fatty acids (PUFA) are readily taken by cancer cells and have been used to improve cell targeting. CA-4-PUFA conjugates were synthesized by coupling combretastatin A-4 with several saturated and unsaturated fatty acids. The conjugates were characterized by NMR, FTIR and MS. The cytotoxicity of the compounds was evaluated against human breast cancer cells (MCF-7) using an MTS assay and the inhibition of tubulin polymerization was determined using a standard turbidity assay. Although all conjugates had an effect on tubulin polymerization, only the arachidonic acid conjugate 87 displayed cytotoxicity similar to the natural product. A CA-4 peptide conjugate (figure 25) targeted to prostrate cancer cells was also synthesized. This analogue will exploit the proteolytic activities of prostate specific antigen (PSA) to convert an inactive CA-4 pro drug into active cytotoxic agent within the tumour thus improving bioavailability and efficacy. Dihydroartemisinin 2 -an artermisinin derivative and 2-methoxyestradiol 4, an estrogen hormone metabolite have been known as potential cancer chemotherapeutic agents. These compounds have both in vitro and in vivo anticancer activity in different types of human cancer cells, such as gastric cancer, osteosarcoma, breast cancer, esophageal cancer, hepatocellular carcinoma, prostate cancer, pancreatic cancer, ovarian cancer and lung cancer. Polyunsaturated fatty acid conjugates of both compounds were synthesized and characterised and like the CA-4 PUFA conjugates, these analogues will readily be taken up by cancer cells thereby improving their efficacies. In addition, dimers of natural occurring plant metabolite, betulinic acid 3 which posseses anticancer activities were made and characterised with the view of testing their anticancer activity.

Introduction: Two pore domain potassium (K2P) channels are responsible for background currents that regulate membrane potential and neuronal excitability. Compounds which alter the activity of these channels are predicted to have therapeutic potential in treating CNS disorders. Members of the TREK family of K2P channels (TREK1 and TREK2) have been shown to play an active role in neuroprotection, depression and pain, whilst TRESK, with high expression in sensory neurons, has a role in nociception. Sipatrigine, a neuroprotective agent and a derivative of the anticonvulsant lamotrigine, is a known antagonist of TREK channels whilst lamotrigine is thought to primarily inhibit TRESK channels. A new compound, Cen-092-C, has also been developed which is structurally similar to lamotrigine. However, its effects on K2P channels are unknown. To understand the mechanism of channel inhibition by drugs, the structure of TREK2 was solved and was co-crystallised with norfluoxetine. This showed that fenestration sites were important in channel and current inhibition. Furthermore, TRESK docking studies showed that F145 and F352 function in a similar way to TREK2 fenestration site, as the bulky phenylalanine faces into the pore, and are thought to be important for compound binding. The aim of this study is to clarify to differences in the inhibitory effect of these compounds on the selected K2P channels and to investigate the mechanism by which these compounds inhibit the channels current. Methods: Wild-type (WT) and mutated human K2P channels were transiently expressed in tsA-201 cells. The currents were measured using whole-cell patch-clamp electrophysiology. Results: Sipatrigine was shown to inhibit both TREK1 and TREK2 current. Lamotrigine was also found to inhibit TREK1 and to a lesser extent TREK2. Cen-092-C was found to be less effective on TREK1 and TRESK current compared to sipatrigine, but similar to lamotrigine results. The sipatrigine inhibitory effect, but not lamotrigine, was reduced by mutations on the M4 region at the fenestration site of TREK1 and TREK2 (L286 and L320). This sensitivity is selective at this site as other mutations in the central cavity showed no change in sipatrigine inhibition. Interestingly, the gain-of-function mutation (TREK1 E306A) on the C terminus showed a reduced sipatrigine inhibition. The effect of sipatrigine on TREK2 showed an over-recovery of current following wash-off of the compound. The wash-off current increase was not seen if the N-terminus length is forced into intermediate and short isoform. Sipatrigine inhibition was significantly decreased when the N-terminus was truncated. Sipatrigine has been shown to strongly inhibit TRESK. Lamotrigine was seen to inhibit TRESK current, however significantly less effective compared to sipatrigine. Furthermore, lamotrigine did show state dependent inhibition when TRESK is in the fixed activated state. Cen-092-C was also found to inhibit TRESK to a similar degree to lamotrigine, however there was no state dependent inhibition on TRESK current. The effects of these antagonists on TRESK has been shown to be abolished by mutations on two sites at the central cavity (F145 and F352). Conclusion: Lamotrigine was found not to be TRESK selective, contrary to other studies. Sipatrigine and lamotrigine inhibition works through binding to the channel. The fenestration site in both TREK1 and TREK2 has been found to be an important binding site of sipatrigine, differing from lamotrigine. This suggests that the structurally similar compounds bind to different regions of the TREK channels. Furthermore, the over recovery of TREK2 current after sipatrigine wash off is believed to show the compound's biphasic effect, where the underlying enhancement of current is hidden by the action of inhibition. The N-terminus is therefore believed to be important in regulating sipatrigine action on TREK2. It remains unclear whether the TRESK potential binding sites (F1452 and F352) are important in compound binding as the inserted mutation is believed to shift the channel to constant active state. The newly developed compound Cen-092-C shows a significantly greater degree of inhibition of TRESK when compared to TREK1. Cen-092-C and lamotrigine inhibition of TRESK is not significantly different. Lamotrigine inhibition of TRESK current is state dependent whereas sipatrigine and Cen-092-C inhibition of TRESK current is shown as state independent. All of this together could lead to a better understanding of how neuroprotective agents effect TREK and TRESK channels and could contribute to the design of more efficient ligands.

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