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1
Bourne, Gerald W. "The synaptic pharmacology of Phencyclidine in the hippocampal formation /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65384.
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Rodgers, Sarah. "Evaluation of a pharmacist-led intervention to reduce prescribing costs in general practice." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/13862/.
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Introduction and aim It has been suggested that the employment of pharmacists in general practice might moderate the growth in prescribing costs. However, empirical evidence for this proposition has been lacking. The aim of this study was to evaluate a controlled trial of pharmacist-led intervention in general practice to determine whether intervention practices made savings relative to controls and if so, exactly how these savings were made and whether quality of prescribing was maintained. Since this process of rationalisation has implications for patients, an additional aim was to explore the views of patients on changes made to their medication. Methods The study was an evaluation of an initiative set up by Doncaster Health Authority. Eight practices received intensive input from five pharmacists for one year (September 1996 to August 1997) at a cost of £163 000. Changes in prescribing patterns were investigated using Prescribing Analysis and CosT (PACT) data by comparing these practices with eight individually matched controls for both the year of the intervention and the previous year. A postal survey of 314 patients who had undergone a change in medication between October 1997 and January 1998 was used to explore patient views. Results The evaluation showed that the rise in prescribing costs for intervention practices was significantly lower than for control practices (p=0.02S). Had the cost growth of the intervention group been as high as that of the controls, their total prescribing expenditure would have been around £347 000 higher. Detailed analysis showed that these savings were achieved by controlling both prescribing volume and cost per unit volume in areas believed to be without detriment to patient care. The majority of patients were reasonably satisfied or very satisfied with the way in which they found out about their medication change and satisfaction was positively associated with being told why the change was taking place, being given a choice and being told by the GP, a practice pharmacist or by letter. Conclusions Compared with previous studies, this evaluation has advantages in the fact that a control group was used to compare changes in prescribing patterns. The evaluation has shown that the use of pharmacists controlled prescribing expenditure sufficiently to off-set the costs of their employment. Results of the patient survey indicated that patients were not so much concerned about changes in medication per se, but rather the manner in which it was conveyed to them. These results have important implications for the control of prescribing costs in primary care. However, this study took place in motivated practices that had relatively high prescribing costs and this may limit the generalisability of the results.
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Ramsay, Gregor Alan. "Depressant effects of general anaesthetics on cardiac muscle." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314918.
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Saunders, Robert Edward. "Pharmacists in general medical practice : a case study of clinical commissioning groups." Thesis, Keele University, 2018. http://eprints.keele.ac.uk/5106/.
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Pharmacists have been identified to address the increasing workload in United Kingdom (UK) general practice. A pilot has been commissioned by National Health Service England (NHSE) to upskill pharmacists for this purpose. Evaluation is underway and early reports indicate that there have been integration issues. The value of pharmacists working in general practice and the level of training required for the role are not fully understood. The research reported in this thesis was started before the NHSE pilot. It was conducted to understand the background of Clinical Commissioning Group (CCG) practice pharmacists (PPs), and their interactions with stakeholders. The rationale was to provide an insight into their working relationships and to generate recommendations to support the integration of pharmacists into general practice. The project was conducted in four CCGs in the West Midlands in 2014 using an interpretive/collective case study approach incorporating mixed methods for data collection. Quantitative data was collected on the background, employment and activities of PPs. Qualitative data was collected on stakeholders’ views of the CCG PP role from commissioners, general practitioners (GPs), and patients. Different commissioning models for PPs were studied to provide a deeper understanding of PPs’ interactions. The workload problems in general practice subsequently modified the focus of this thesis to determine the value of PPs to general practice, the level of training required and to propose a model for the integration of pharmacists into UK general practice. The thesis study identified some determinants of integration found in previously published studies but also discovered new areas specific to the integration of pharmacists into UK general practice. These areas can be grouped into three elements - the pharmacist’s skills and attributes, practice level facilitation and national level support. They are presented as a unique Model for the Successful Integration of Pharmacists into General Practice Teams.
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Mackenzie, Amanda Elaine. "An investigation of the molecular pharmacology of G protein-coupled receptor 35." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6392/.
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G protein-coupled receptors (GPCRs) are seven-pass integral membrane proteins that act as transducers of extracellular signals across the lipid bilayer. Their location and involvement in basic and pathological physiological processes has secured their role as key targets for pharmaceutical intervention. GPCRs are targeted by many of the best-selling drugs on the market and there are a substantial number of GPCRs that are yet to be characterised; these could offer interest for therapeutic targeting. GPR35 is one such receptor that, as a result of gene knockout and genome wide association studies, has attracted interest through its association with cardiovascular and gastrointestinal disease. Elucidation of the basic physiological function of GPR35 has, however, been difficult due a paucity of potent and selective ligands in addition to a lack of consensus on the endogenous ligand. Herein, a focussed drug discovery effort was carried out to identify agonists of GPR35. Various in vitro cellular assays were employed in conjunction with N- or C-terminally manipulated forms of the receptor to investigate GPR35’s signalling profile and to provide an assay format suitable for the characterisation of newly identified ligands. Although GPR35 associates with both Gαi/o and Gα13 families of small heterotrimeric G proteins, the G protein-independent β-arrestin-2 recruitment format was found to be the most suited to drug screening efforts. Small molecule compound screening, carried out in conjunction with the Medical Research Council Technology, identified compound 1 as the most potent ligand of human GPR35 reported at that time. However, the lower efficacy and potency of compound 1 at the rodent species orthologues of GPR35 prevented its use in in vivo studies. A subsequent effort, carried out with Novartis, focused on mast cell stabilisers as putative agonists of GPR35, revealed lodoxamide and bufrolin as highly potent agonists that activated human and rat GPR35 with equal potency. This finding offered–for the first time–the opportunity to employ the same GPR35 ligand between species at a similar concentration, an important factor to consider when translating rodent in vivo functional studies to those in man. Additionally, using molecular modelling and site directed mutagenesis studies, these newly identified compounds were used to aid characterisation of the ligand binding pockets of human and rat GPR35 to reveal the molecular basis of species selectivity at this receptor. In summary, this research effort presents GPR35 tool compounds that can now be used to dissect the basic biology of GPR35 and investigate its contribution to disease.
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Galue, Adriana M. "Electrophysiology and pharmacology of persistent sodium currents present in the mammalian brain." Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29805.
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Persistent sodium conductances are important both in normal and pathological brain states. In the first part of the present study we characterized a Type of persistent sodium conductance (INap) present in stellate cell neurons of the layer II medial entorhinal cortex area of the rat brain. To accomplish this task, we used the whole-cell configuration of the patch clamp technique to record sodium currents in dissociated entorhinal neurons. It was found that INap represents 5 to 10% of the amplitude of the fast inactiuvating sodium conductance (INaF). In addition, I Nap activates at potentials 10mV more negative than INaF, and this persistent conductance is present at potentials more positive than those expected for a window current. These results show that INap in entorhinal neurons is due to a distinct subset of non-inactivating sodium channels, rather than a window current.In the second part of the study, we carried out a pharmacological characterization of the Type III sodium channel, which is a molecular model to study persistent conductances. We tested the actions of phenytoin, carbamazepine, tetracaine and topiramate on these channels when expressed in the Xenopus oocyte system using the two-electrode double-voltage recording technique. It was found that all the drugs except topiramate, block the Type III currents in a voltage dependent manner. The sensitivity of Type III currents to drugs was not affected by coexpression of auxiliary sodium channel beta subunits, and it was similar to the sensitivity of fast-inactivating Type IIA sodium channels.
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Edwards, John James. "Quality indicators for the care of osteoarthritis in general practice : identification, synthesis, and implementation." Thesis, Keele University, 2017. http://eprints.keele.ac.uk/3527/.
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Background Previous studies have demonstrated suboptimal management of care for osteoarthritis (OA). The objectives of this study were to (i) identify indicators of quality of care for OA in general practice, (ii) measure quality of care using routine general practice records and through an enhanced recording template (iii) estimate the effect of the template introduction on quality of care, and (iv) assess the feasibility of quality indicators as trial outcome measures. Methods A systematic review and narrative synthesis of quality indicators was undertaken. An iterative process of development resulted in an electronic template to record management of OA in consultations, based on identified quality indicators. This was triggered by a case definition of clinical OA derived through consensus. An assessment of coding, diagnostic misclassification using consultation narrative, and baseline recorded quality of care before template installation in eight practices was undertaken. Measurement after template installation facilitated a before-and-after comparison of care. The indicators were used as secondary outcomes in a cluster-randomised trial of a model OA consultation. Results There were fifteen valid, feasible quality indicators. Consultation prevalence of clinical OA was comparable to other estimates but up to one-third of cases may not represent true OA. Prescribing and referral data were well-captured in the routine record; assessment and core treatment indicators (such as education and advice) were not and so were included in the recording template. The template had small-to-moderate effects on weight recording, and paracetamol and topical anti-inflammatory prescription. Assessment of the effect of the model consultation was limited by high baseline quality achievement and variation between trial arms, practices and clinicians. Conclusion Assessment of quality of care for OA in general practice through quality indicators is feasible but comprehensive assessment requires enhanced recording approaches. Inter-clinician variability requires further understanding and reduction, and triangulation with patient-experienced quality is needed.
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Coxon, Domenica. "Deciding to consult the general practitioner for joint pain : a choice-based conjoint analysis study." Thesis, Keele University, 2013. http://eprints.keele.ac.uk/3805/.
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A substantial proportion of older adults with non-inflammatory joint pain do not consult their general practitioner (GP) despite apparent clinical need. This thesis describes the development, execution, and interpretation of an original study using conjoint analysis – a fairly novel approach with some advantages over conventional observational and qualitative studies - to understand the relative importance of need-related and service-related factors on the decision to consult the GP. Background reading, a systematic review of previously published conjoint analysis studies, and a series of developmental studies involving patients and members of the public informed the design of the main study. A partial-profile choice-based conjoint (PPCBC) questionnaire was chosen, comprising 10 choice tasks using a combination of selected attributes (pain characteristics, pain disruption to everyday life, comorbidity, assessment and investigations available, available treatment options, and perceived GP attitude). The PPCBC questionnaire was postally-administered to 1170 adults aged 50 years and over with hip, knee, or hand pain identified from an existing population cohort study in North Staffordshire. 863 questionnaires were returned (adjusted response rate 74%; mean age: 70 years; 55% female) and well-completed ( < 5% missing data). The extent to which pain disrupted everyday life (1.10 logits) and perceived GP attitude (0.86 logits) were the most important determinants of the decision to consult the GP. Service factors were highly influential with a ‘negative’ GP attitude potentially outweighing the perceived value of optimal assessment and management. Latent class analysis identified possible subgroups with differing strengths of preference. Conjoint analysis is feasible and offers unique insights into the relative importance of actual and hypothetical services. While it presents many challenges - extensive developmental testing, complex design and analysis procedures, ability to integrate findings from a range of different methods – it can provide important information on patients’ preferences for existing and emerging treatments and models of care.
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Mulholland, Thomas David. "The peripheral vascular effects of general and regional anaesthesia in children." Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261940.
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Takahashi, Hidenori. "Effects of general anaesthetics on calcium and potassium channel currents in heart cells." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239241.
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Gibbs, Sharon. "Informing patients about medicines : an evaluation of prescription information leaflets in general practice." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280750.
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Ramsey, Nicole B. "Bilayer perturbation is a distinct parameter for regulating the experimental use of biological probes and the development of antimalarials." Thesis, Weill Medical College of Cornell University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3580196.
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The controlled production and degradation of cAMP allows for control of many different signaling pathways. cAMP is produced by genetically distinct transmembrane (tmAC) and soluble (sAC) adenylyl cyclases; cAMP is catabolized by phosphodiesterases (PDEs). The relative contributions of sAC and tmAC to cAMP production, and of the PDEs to cAMP catabolism, usually are explored using pharmacological interventions. Because the compounds used to manipulate intracellular cAMP levels must cross cell membranes, they need to partition into lipid bilayers, which raises the question whether they could alter cell function by mechanisms that are unrelated to the changes in cAMP turnover. Indeed, many of these compounds are known to alter the function of other membrane proteins at concentrations that overlap with those used to target cAMP metabolism. Moreover, the concentration range(s) used to obtain the same effect vary widely among experiments, suggesting that these compounds elicit off-target effects that do not involve conventional cAMP signaling pathways. I therefore explored the lipid bilayerperturbing effects of 17 commonly employed modifiers of sAC, tmAC and PDE activity using a GBFA. Twelve compounds perturbed the bilayer at commonly used concentrations. Thus, in addition to their effects on cAMP metabolism, these molecules may alter cell function by being promiscuous modifiers of membrane protein function, meaning they should be used with care. Effects that occur only at concentrations that are three or more times higher than those for half-maximal effect (on the intended target) should be interpreted with caution.
In addition to being important for the interpretation of experiments that explore biological function with small-molecule probes, bilayer perturbation is also an important parameter for drug discovery. In this thesis, I focused on how to improve the development of new malaria therapies, which is necessary due to the perpetual development of resistance to current therapies. The Medicines for Malaria Venture developed the Malaria Box to facilitate the drug development process (and reduce the cost) by providing pharmaceutical company-vetted drug candidates to academicians. To explore whether testing for membrane effects might reduce the expenses required for drug development, I tested the 80 potent compounds from the Malaria Box for bilayer-mediated effects on membrane protein conformational changes (as a measure of literature. However, some significant differences should be further examined in other international teaching environments.
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Elmi, Ahmed. "Safety of medicines with respect to drug counterfeiting in developing countries." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/52338/.
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Background: This thesis presents a study of the safety of medicines with respect to drug counterfeiting in developing countries (East Africa and the Middle East). Counterfeit medicines are also present in industrialised countries, but not on the same scale as in developing countries. The aim of the study was to establish the responsiveness of health care professionals at the practice level concerning the counterfeiting of medicinal products in developing countries focusing on six countries in the East African region and seven countries located in the Middle East. Method: The method of data acquisition used was by survey questionnaires issued in 13 developing countries (6 in East Africa and 7 in the Middle East). The questionnaires were delivered to the respondents either personally or by e-mail and the questionnaire, responses were returned by the same means. Respondents returned their questionnaire forms direct to the author either on the same day or later by e-mail. The data were analysed with regard to the specific questions. Results: The study findings suggested that the poorer the country, the higher the degree of counterfeiting. All the respondents (n: 2180) agreed that there was a fake or counterfeit medicine problem in their own country (71% of respondents in Africa and 63% of respondents in the Middle East considered this a major problem). Both branded and generic drugs were counterfeited and the extent of the problem and several other factors concerning counterfeited drugs differed significantly between industrialised and developing countries. The difference depended on drug regulation control and enforcement and also on the quality and the prices in the legal supply chain. In most industrialised countries like the USA, Japan or the members of the EU, the level v of drug counterfeiting is <1% of the total medicines market value. An exception is the former Soviet Union where up to 20% of the market is occupied by counterfeit drugs. In contrast, within regions of Africa, Asia and parts of Latin America, between 10-30% of the available medicines are fakes (WHO 2006) Conclusions: The study showed that healthcare workers were aware of the prevalence of counterfeit medicines and quite a number of them had encountered them in their supply role. There is an indication that the respondents tried to assure themselves of the quality of the drugs they purchased by using several methods. However, no rigorous effort was taken to confirm as well as report suspected counterfeit drugs to regulatory authorities. In the industrialised world, medicines regulatory authorities have developed strict standards and controls to ensure the safety and effectiveness of drugs. However, as this study has found, in less developed countries a lack of human and financial resources within the health sector as a whole restricted the activity of regulatory agencies, resulting in a sub-optimally regulated environment in which substandard drug production persisted without detection.
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Chen, Hongzhi. "Discovery of acoustic emission based biomarker for quantitative assessment of knee joint ageing and degeneration." Thesis, University of Central Lancashire, 2011. http://clok.uclan.ac.uk/3151/.
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Based on the study of 34 healthy and 19 osteoarthritic knees in three different age groups (early, middle and late adulthood), this thesis reports the discovery of the potential of knee acoustic emission (AE) as a biomarker for quantitative assessment of joint ageing and degeneration. Signal processing and statistical analysis were conducted on the joint angle signals acquired using electronic goniometers attached to the lateral side of the legs during repeated sit- stand-sit movements. A four-phase movement model derived from joint angle measurement is proposed for statistical analysis, and it consists of the ascending- acceleration and ascending-deceleration phases in the sit-to- stand movement, followed by the descending-acceleration and descending-deceleration phases in the stand-to-sit movement. Through the quantitative assessment of joint angle signals based on the four-phase model established, statistical differences of different knee conditions related to age and degeneration were discovered based on cycle-by- cycle variations and movement symmetry. For AE burst signals acquired from piezo-electric sensors attached to the knee joints during repeated sit-stand-sit movements, the statistical analysis started from the quantity of AE events in the proposed four movement phases and extended to waveform features extracted from AE signals. While the quantity of AE events was found to follow certain statistical trends related to age and degeneration in each movement phase, detail statistical analysis of AE waveform features yielded the peak amplitude value and average signal level of each AE burst as two most significant features. An image based knee AE feature profile is presented based on 2D colour histograms formed by the peak amplitude value and average signal level in four movement phases. It provides not only a visual trend related to knee age and degeneration, but also enables visual assessment of the
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Williams, Andrew. "The diagnosis and treatment of myocardial and arterial dysfunction in Marfan Syndrome." Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/38024/.
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Marfan Syndrome is a genetic, cardiovascular disease caused by a defect in the fibrillin 1 gene on chromosome 15. This defect causes abnormal deposition of elastin throughout the body. Elastin is found in many organs including the aorta. Marfan Syndrome is diagnosed by the Ghent criteria. The mean age at death is 44 years for men and 47 years for women, and about 70% die from acute cardiovascular complications, mainly aortic dissection. The assessment and treatment of the aortic complications of Marfan Syndrome has not changed for many years. Serial echocardiography is performed to measure the aortic root diameter. If thought to be increasing in size, beta blockers are prescribed to delay aortic dilatation and surgery, and to prevent aortic dissection or rupture despite the paucity of good research data. I have investigated three novel diagnostic tools: Tissue Doppler Imaging, Applanation Tonometry and Wave Intensity Analysis which have potential advantages in the assessment of the left ventricle and aorta and their interaction in Marfan Syndrome. I also investigated three drugs a beta blocker, an angiotensin converting enzyme inhibitor and a calcium channel blocker to look at their impact on some of the parameters measured by these three novel tools in a double-blinded, randomised cross-over trial. I conclude that these three novel tools would be useful adjuncts in monitoring Marfan Syndrome and their response to treatment. I also found that beta blockers may still have a role to play in delaying and preventing aortic complications when given together with an angiotensin converting enzyme inhibitor, calcium channel blocker or angiotensin receptor blocker. There are, however, other issues that need addressing to improve the management of the cardiovascular complications of Marfan Syndrome. This includes a multi-team approach to this multi-system disease and improvements in the standard of research.
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McCully, William Francis. "The antibacterial activity of tea infusions and their effect against the hospital pathogen clostridium difficile." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/52337/.
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Clostridium difficile is one of the UK’s most common hospital acquired infections and there is anecdotal evidence to suggest that the bacteria are sensitive to the antibacterial properties of tea. Surprisingly, little research has been undertaken to characterise the inhibitory activity of aqueous tea infusions that are representative of traditional drinking habits. The antibacterial properties of tea are thought to be due to a group of polyphenols called catechins. However, their contribution to the inhibitory activity of tea infusions and their mechanism of action is still subject to debate. An antimicrobial assay, developed using Staphylococcus aureus as a model organism, was used to determine the antibacterial activity of a range of tea infusions against 75 clinical isolates of C. difficile that represented all the major strain ribotypes over 11 years. Green teas demonstrated more potent antibacterial activity than black teas and their activity was positively correlated with antioxidant power, hydrogen peroxide production, and catechin content. Furthermore, the country of origin of the tea affected the catechin content and subsequent antimicrobial activity of the infusion. Detailed chemical analysis using high performance liquid chromatography and counter current chromatography suggests that the antibacterial activity of tea is probably the result of synergistic interactions between a number of catechins rather than the activity of an individual compound. With regards to the mode of action by which tea inhibits C. difficile, electron microscopy studies of the bacterium treated with green tea revealed distinct changes to the outer cell structures of the bacteria. These changes were indicative of cell membrane blebbing, thus supporting the theory that tea compounds interact with the bacterial membrane and/or cell wall. Overall, this investigation concluded that tea infusions have inhibitory activity against C. difficile in vitro and may be useful in the treatment or prevention of C. difficile infections in vivo.
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Zheng, Chen. "The use of excipients to stabilise pressurised metered dose inhalers." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/113171/.
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This thesis concerns investigations of novel pressurised metered dose inhaler (pMDI) formulations containing tiotropium (Tio) in association with a secondary particulate (SP). A number of formulation and hardware variables were studied using in vitro methods to determine their influence on the performance of these novel formulations. Initial studies indicated that Tio was practically insoluble in HFA propellants and its solubility was not increased under raised moisture levels during long-term stability tests. Formulations with L-leucine (Leu) or lactose (Lac) as SP’s were investigated in Tio:SP ratios ranging from 1:2.5 to 1:25 and with different SP sieve fractions from < 20 μm to < 63 μm. Many formulations demonstrated improved aerosol characteristics compared with Tio alone, particularly in through life performance (TLP). The inclusion of fine SP’s (< 20 μm) was found to significantly improve dose uniformity, fine particle fraction (FPF) and fine particle dose (FPD). Tio:Lac formulated in HFA 227 resulted in slightly greater FPF and FPD but also a higher mass median aerodynamic diameter (MMAD) than when formulated in HFA 134a. With respect to the hardware parameters investigated, smaller actuator orifices (in the range 0.25-0.46 mm) and lower valve volume (25 μl instead of 50 μl) were generally associated with significantly increased FPF and reduced MMAD, whereas a smaller canister volume and fluorocarbon polymerization canisters tended to improve TLP. In comparison with marketed Tio products, comparable FPF’s to Spiriva Handihaler® (41%) and Spiriva Respimat® (53%) were demonstrated with bespoke Tio:Lac and Tio:Leu formulations respectively. The Tio:Leu formulation also had a much lower submicron fraction of Tio than Spiriva Respimat®. This research concerning Tio:SP pMDI formulations has demonstrated the advantages of including a SP to promote drug-SP association in the HFA suspension and promoting particle de-aggregation during propellant atomisation. Further research regarding direct measurement of particle interactions and aerodynamic behavior is warranted.
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Paul, Graham R. "Defining dosimetry and implications for aerosol presentation for non-clinical development of respiratory drugs." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/113410/.
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Strategies for expediting preclinical development of drugs include using alternative (different to clinical) formulations or exposure routes to reduce compound usage. This may alter pharmacokinetics and hence efficacy and/or toxicopathology compared with the final formulation. Three p38 mitogen-activated kinase inhibitors (similar in vitro potency) with different physicochemical properties were administered to rats as dry powder or nebulised aerosols to investigate the influence of changes in particulate form on in vivo endpoints. When rats settled in restraint tubes before aerosol administration, inhaled doses calculated from lung function measurements were consistent with values derived from body weights using a published algorithm. Drug-lung deposition was 12% of the inhaled dose, correlating with the rat deposition fraction (10%) used by US-FDA officials when reviewing regulatory submissions. Drug persistence (GSK-899) in rat lung was associated with increased efficacy (inhibition of lipopolysaccharide-induced inflammation) four hours post challenge, compared with two readily absorbed drugs. However, administration of GSK-899 at a higher dose for 28 days resulted in accumulation of drug and alveolar macrophage aggregates in lungs with infiltration of neutrophils, a consequence of accumulating ‘nuisance particles’ and mild irritancy by GSK-899. GSK-361 (lipophilic; membrane permeable) resulted in lower lung exposure and efficacy, and no lung toxicopathology. Repeating experiments with compounds of different pharmacologies would confirm if these physicochemical properties support general trends for inhaled drugs or represent standalone results for these molecules. Changing aerosol form did not fundamentally change the nature of toxicopathology but presented technical limitations for evaluating the dose response. This thesis demonstrated changes in aerosol form could modulate dose response without changing the nature of toxicopathology. Membrane permeability had a more profound effect on lung clearance and toxicopathology than aqueous solubility. Given technical limitations for drugs of low aqueous solubility, the aerosol form intended for clinical formulations should be used in early preclinical studies.
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Baxani, Kamal Divesh. "Hydrogel encapsulated droplet interface bilayer networks as a chassis for artificial cells and a platform for membrane studies." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/112707/.
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There has been increasing interest in droplet interface bilayers (DIBs) as novel devices for the study of lipid membranes and the development of artificial cell systems. Although DIBs have demonstrated to be useful in a number of laboratory applications, their wider use is hampered by a limited ability to exist untethered and remain mechanically stable beyond controlled laboratory environments. In this thesis, a microfluidic system is developed which enables the facile generation of hydrogel-encapsulated DIB networks which are freestanding and can exist in air, water and oil environments, without compromise to their ability to interface with the surrounding environment. Electrophysiology is employed in order to demonstrate the formation of bilayers between the encapsulated DIBs (eDIBs) and their external environment, achieved via the incorporation of the transmembrane pore α-Hemolysin. The eDIBs produced here are able to form higher-order structures akin to tissues via their assembly and adherence to one another, further demonstrating their potential to act as a chassis for artificial cells. Furthermore, the potential of eDIBs to be used as a platform for membrane studies is demonstrated via their use as a high-throughput array for membrane disruption fluorescence measurements using a plate reader, which makes use of the ability of eDIBs to be generated in large numbers as well as to be mechanically handled and placed in the wells of a 96-well plate. Fluorescence measurements were taken on up to 47 eDIBs simultaneously, and were able to detect bilayer leakage through pores as well as bilayer failure. The above experiments comprise the design, manufacture and use of a novel kind of DIB construct as a chassis for artificial cells and a platform for high-throughput membrane studies. It is proposed that eDIBs may help in realising the unfulfilled potential of DIB networks in applications in healthcare and beyond.
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Al, Thaher Yazan. "Antimicrobial drug LbL-assembled delivery system for orthopaedic nanocomposite bone cements." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/112718/.
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Total joint replacement (TJR) is commonly used for the treatment of end stage arthritis. The use of Poly-methylmethacrylate (PMMA) bone cement is a gold standard TJR, where it is frequently used for local delivery of antibiotics to provide prophylaxis from prosthetic joint infections (PJI). Currently used antibiotic loaded bone cements have many limitations, including burst release which fall below inhibitory levels leading to the selection of antibiotic resistant strains. This study aims to provide a controlled release for antimicrobial agents from bone cement to provide prophylaxis from postsurgical infections. For this purpose, gentamicin and chlorhexidine were loaded alone or in combination on silica nanoparticles surface using layer-by-layer coating technique (LbL). A novel LbL construct was built using hydrolysable and non-hydrolysable polymers. The nanoparticles were characterised by transmission electron microscopy, thermogravimetric analysis, zeta measurement, and drug release in different media. Then, antimicrobial agents LbL coated nanoparticles were incorporated into PMMA cement and the nanocomposite is characterized for drug release, antimicrobial, mechanical, rheological properties and cytocompatibility. The build-up of LbL coating was confirmed by thermogravimetric analysis and zeta measurements. The release of antimicrobial agents was controlled for > 30 days for different drugs used. The nanocomposite drug release profile also continued > 30 days at concentration higher than the commercial formula t ion containing the same amount of antibiotics, where burst release for few days were observed. Moreover, the nanocomposite showed superior antimicrobial inhibit ion for bacterial growth, without adversely affecting the mechanical properties. Different nanocomposites showed cytocompatibility when tested against Saos-2 cells. Techniques from a variety of disciplines were employed in this study and this interdisciplinary approach has allowed many features of PMMA bone cement to be investigated. The developed nanocomposites can have the potential to reduce PJIs, and the newly developed LbL nano-delivery system may have wider application in a variety of biomaterials.
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Rodrigues, Melissa. "Preventing nano and micro wear-particle induced inflammation." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/114163/.
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Aseptic loosening, as a consequence of an extended inflammatory reaction induced by wear particles, remains the most common complication of total joint replacement (TJR), representing a major problem for the long-term success and survival of prostheses. Despite it is high incidence, in the last decade any therapeutic approach has been found to treat or avoid aseptic loosening, leaving revision as the only effective treatment for this condition. The local delivery of anti-inflammatory drugs to modulate wear-induced inflammation has been regarded as a potential therapeutic approach to avoid aseptic loosening. In this work, an anti-inflammatory drug-eluting implant model system was developed and characterised. The model system was obtained by attaching DEX to functionalised-TiO2 particles, through different synthetic routes: i) by covalently binding DEX to carboxyl-functionalised particles (amino or mercapto routes) or ii) by coating amino-functionalised particles using Layerby- Layer (LbL) technique. The chemical and physical properties of DEXloaded functionalised TiO2 particles have been determined and the release profiles investigated. Depending on the synthetic route, the DEX release period can vary from hours (amino, mercapto routes) to 3 weeks (LbL route). The model system was then tested for its cytotoxic and anti-inflammatory properties in a rapid and reproducible in vitro mouse macrophage-like cellular model, by utilizing murine RAW 264.7 cells. In this model lipopolysaccharide (LPS) was utilized to activate the Raw macrophages, resulting in the secretion of pro-inflammatory cytokines, including nitric oxide (NO) and tumour necrosis factor alpha (TNF-α), the suppression of which was utilized to investigate the anti-inflammatory effect of DEX released from functionalised-TiO2 particles. In vitro studies showed that DEX decreased LPS-induced NO and TNF-α production at non-cytotoxic concentrations, where DEX released from LbL particles showed the most effective suppression of inflammation for at least 2 weeks. Collectively, these findings show that the model system developed can be a potential therapeutic approach to avoid wear-debris induced aseptic loosening of TJR.
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Konstantinou, Maria. "Characterising In-111-anti-γH2AX-TAT in targeting the DNA damage signal associated with Wnt activated colorectal cancer." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/111847/.
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Background: Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the UK and has a poor 60% 5-year survival rate. The Wnt signalling pathway is fundamental for homeostasis of the intestinal epithelium and its deregulation drives development of CRC and induces DNA damage. Histone-2AX (H2AX) is a component of the nucleosome whose phosphorylated form, γH2AX, is a marker of DNA damage. Objectives: Using a well-characterised inducible CRC mouse model of early Wnt deregulation, and established Apc-deficient driven tumour and ex vivo organoid models, we have assessed whether the spontaneous DNA damage generated in these models can be targeted using 111In-anti-γH2AX-TAT (RH2AX), a radio-labelled antibody targeting γH2AX. Methods: Deletion of the Apc gene was effected in the intestine of VilCreERApcfl/fl and Lgr5CreERApcfl/fl models by intraperitoneal or oral induction with tamoxifen. γH2AX immunohistochemical (IHC) characterisation of intestines were performed as well as γH2AX whole mount immunofluorescent analysis on organoids derived from them. RH2AX, an anti-γH2AX antibody conjugated to the cell-penetrating peptide TAT to allow cellular internalisation and nuclear localisation, was used in these models as an imaging agent SPECT/CT imaging and biodistribution studies were conducted after oral induction of VilCreERApcfl/fl and intravenous injection of RH2AX. γH2AX and Lgr5 FACS analysis were carried out on intestinal crypt cells of VilCreERApcfl/fl mice expressing Lgr5-EGFP reporter. Results: Intestinal Apc deficiency increased DNA damage levels in the small intestine of both dysplastic (VilCreERApcfl/fl) and tumour CRC mouse (Lgr5CreERApcfl/fl) models. Apc-deficiency-associated DNA damage is most likely generated through WNT signalling pathway activation and, more specifically, by c-Myc transcription. For the first time, we demonstrated that intestinal dysplasia can be identified through in vivo SPECT imaging, using low SA RH2AX treatment. Low SA RIC treatment in intestinal dysplasia increased the DNA damage levels in healthy and Apc-deficient small and large intestines, increased proliferation in the Apc-deficient tissue and resulted in variable levels of apoptosis depending on the tissue. Conclusion: These findings together indicate that DNA damage is induced by Apc-deficiency, and that there is the possibility to exploit the endogenously-increased DNA damage signal, γH2AX, to attract the RH2AX for in vivo imaging of intestinal dysplasia. This could help diagnose early stages of CRC to provide patients with the appropriate treatment sooner and increase their survival.
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Emery, Sophie. "Development of analytical methods for the stability assessment of parenteral nutrition." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/112136/.
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Parenteral nutrition (PN) provides intravenous nutritional support to patients with reduced gastrointestinal function. A PN bag comprises the basic building blocks of the food groups: lipids, glucose, amino acids, vitamins, electrolytes and trace elements. Recently there has been an increase in demand for extended storage periods for PN bags, to ease management of an increasing home care market. Prior to a PN formulation being deemed safe for a patient, a laboratory simulation is carried out on the proposed admixture under the requested storage and administration conditions. Currently only the physical stability is assessed; physical testing provides no information on the quantity of each component remaining in the bag after storage. Consequently, there is a need for assessing the chemical stability of PN to indicate the quantity of each component that remains in the PN bag. A commonly used amino acid product, Aminoven® 25, contains 16 amino acids; this work aimed to develop a HPLC assay capable of quantifying the amino acids in an aqueous PN bag containing Aminoven® 25. Fluorescence detection was used as it is a highly selective method of detection, which was preferable due to the number of components in PN. To detect the amino acids, as they don’t naturally fluoresce, derivatization was carried out using ortho-phthalaldehyde to form a fluorescing derivative. The developed assay resulted in validation of thirteen of the amino acids in Aminoven® 25. In addition, the method was shown to be unaffected by the iv presence of aqueous PN components, so this method is suitable for quantifying thirteen amino acids in aqueous PN containing Aminoven® 25. This assay can be used for assessing the stability during stability testing and confirming the quantity of amino acids after compounding for quality control release.
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Vieira, Goncalves Leonam. "Mechanisms of virucidal action of alcohol and metallic ions against nonenveloped viruses." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/111705/.
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Studying the mechanism of action (MoA) of biocides against pathogenic microorganisms is crucial to understand their efficacy and limitations, and to develop more efficient microbicidal formulations. Combining alcohol and zinc has been reported to enhance microbicidal activity, but the reasons for such activity are unknown. This study focuses on the impact of combining ethanol and zinc salt at pH 10.5 against nonenveloped viruses. The study is focused on three different aspects: i) virucidal activity screening of ethanol:zinc combinations against bacteriophages and human viruses; ii) impact of ethanol:zinc combinations on virus structure, particularly the viral capsid and nucleic acid, using Transmission Electron Microscopy (TEM); Atomic Force Microscopy (AFM) and agarose gel DNA electrophoresis and iii) chemical speciation and stability of ethanol:zinc combinations over time. The combination of ethanol with zinc salt was found to be more effective against viruses than control formulations containing sole active ingredients and/or excipients only. Activity test of 40%(w/v) ethanol with 0.1% (w/v) zinc salt with excipients (RB- 002 formulation) against F116 and adenovirus type 2 (AdV2) at 60 min contact time yielded 0.68 ± 0.02 and 5.26 ± 0.10 log10 reduction, respectively. In comparison, 0.1% (w/v) zinc salt only with excipient (RB-002G formulation) showed no virucidal activity against bacteriophage F116 (0.14 ± 0.02 log10 reduction) and AdV2 (0.80 ± 0.12 log10 reduction) in suspension. Differences between activities against bacteriophage MS2 and poliovirus type 1 were similar as the ones found between F116 and AdV2. Formulation containing 40%(w/v) ethanol with 0.1% (w/v) zinc salt produced a range of structural damage to F116 and attP AdV5 indicating possible capsid alteration. Effect of the combined formulation on viral capsid was confirmed with AFM with a possible decreased in virus capsid stiffness and significant virus capsid height reduction over 10 min contact time. F116 DNA damage was detected upon exposure to 40%(w/v) ethanol with 0.1% (w/v) zinc salt with excipients, but no damage was detected on AdV2 DNA through electrophoresis analysis. The alcohol/zinc formulation system at pH 10.5 was shown to have promising virucidal activity against non-enveloped viruses at room temperature following an alteration of the viral capsid, and possible damage to the viral nucleic acid. This study also showed the limitations of using bacteriophage as surrogate for mammalian viruses.
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Moss, Joe. "Anti-inflammatory actions of nutraceuticals : novel emerging therapies for atherosclerosis?" Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/111849/.
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Background Cardiovascular disease (CVD)-related events such as myocardial infarction and stroke remain the world’s leading cause of death. The incidence of CVD-related events is expected to rise in the future due to the increase in the global prevalence of obesity and diabetes, in addition to less economically developed countries adopting a western style diet. Atherosclerosis is a chronic inflammatory disease which is the underlying cause of CVD and characterised by the build-up of fatty deposits within the walls of medium and large arteries. Macrophages play critical roles during the pathogenesis of atherosclerosis, including the uptake of modified low-density lipoproteins to form foam cells. CardioWise is a dietary supplement developed by Cultech Limited which contains the anti-inflammatory compounds ω-3 PUFAs, flavanols and phytosterols. The aim of this project was to assess the cardiovascular protective effects of CardioWise and its individual components in isolation using in vitro and in vivo model systems. Results Foam cell formation was attenuated in human THP-1 macrophages treated with CardioWise. In addition, CardioWise reduced pro-inflammatory gene expression, monocyte recruitment and M1 macrophage phenotype polarisation. CardioWise was also found to increase HDL cholesterol levels and attenuate circulating levels of pro-inflammatory cytokines in wild type mice. Further investigation identified (+)-catechin within CardioWise as a key beneficial molecule to explore in greater detail. In vitro experiments demonstrated that catechin reduced monocyte migration and reactive oxygen species generation. Wild type mice treated with catechin were also found to receive anti-atherogenic benefits such as increased HDL cholesterol levels and reduced pro-inflammatory cytokine levels. Conclusion The findings of this study show that CardioWise and catechin are capable of exerting strong anti-inflammatory effects on several stages of atherosclerosis disease development in vitro. Furthermore initial in vivo studies using wild type mice revealed that both treatments are also capable of exerting several cardiovascular protective effects. Reasons for these beneficial effects have been proposed in this thesis and future studies outlined.
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Bonhomme, Vincent. "Contribution to the study of the mechanisms of the loss of consciousness induced by general anesthesia : a brain mapping and electrophysiology approach." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0031/MQ64320.pdf.
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Cai, BeiLei. "The role of IL-27 and IL-35 in inflammatory diseases." Thesis, University of Glasgow, 2008. http://theses.gla.ac.uk/420/.
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Rheumatoid arthritis (RA) is an inflammatory autoimmune disease characterized by chronic inflammation within the synovial tissues in multiple joints leading to progressive, erosive destruction of cartilage and underlying joints. The severity of RA is associated with the overexpression of proinflammatory cytokines within the synovial tissue, such as TNF-, IL-1 and IL-6. Recently, IL-17 is thought to play a critical role in maintaining the inflammatory processes within the arthritic joints. Although the etiology and pathogenesis of RA has not been completely elucidated, neutralizing Antibodies against the inflammatory components have been shown to successfully suppress joint inflammation, reduce the relapse rate and delay disease onset in RA patients. Therefore, the expression and regulation of cytokines produced during the disease progression has been the centre of interest in therapeutic studies. Cytokines are important mediators of immune functions in humans and animals. In this thesis, a murine model of RA has been used to investigate the roles of new cytokines Interleukin (IL)-27 and Interleukin (IL)-35. Interleukin (IL)-27, is a heterodimeric cytokine comprised of an IL-12p40 related protein, Epstein-Barr virus-induced gene 3 (EBI3) and a unique IL-12p35 like protein p28. IL-27 is a member of IL-12 family, mainly generated by activated macrophages and dendritic cells. IL-27 binds a receptor composed of WSX-1/TCCR, a ligand-specific chain, and gp130, a signal-transducing molecule shared with other cytokines such as IL-6. IL-27 can promote both pro- and anti-inflammatory immune responses. A novel role of IL-27 regulating autoimmunity has been suggested by experiments on experimental autoimmune encephalomyelitis (EAE) and central nervous system (CNS) inflammation when infected with Toxoplasma gondii. IL-27 suppresses these chronic diseases through inhibiting Th17 activity. Thus, IL-27 may have an important therapeutic potential for treatment of RA in humans. A major aim of this project has been to clone and express a recombinant murine IL-27 in sufficient quantities to study the role of IL-27 in a murine model of RA closely related to the human disease, collagen-induced arthritis (CIA). A short term administration of IL-27 to mice at the onset of the disease had a significantly suppressive effect on disease severity and incidence compared with untreated controls. Mice treated with the recombinant IL-27 also showed reduced serum IL-6, IL-17 and collagen-specific IgG2a. Spleen and lymph node cells from the IL-27-treated mice produced significantly less IFN- and IL-17 compared with cells from the control mice when cultured with collagen in vitro. In contrast, administration of IL-27 to mice during the late phase of CIA significantly exacerbated disease severity. IL-27-treated mice also showed elevated IFN-γ and IL-6 production by the lymphoid cells when compared to untreated mice. However, IL-17 synthesis was not affected between IL-27-treated mice and untreated mice. Consistent with this finding, in vitro IL-27 markedly inhibited the development of Th17 from naïve CD4+, CD4+CD25- and CD4+CD25+ T cells, but had little or no effect on differentiated Th17 cells. Together, these results demonstrated that IL-27 had both pro-inflammatory and anti-inflammatory effects on chronic articular inflammation, mainly associated with Th17 functions. Interleukin (IL)-35, another novel heterodimeric cytokine belonging to IL-12 family, is composed of EBI3 and the IL-12p35 subunit. Little is known about the biological function of IL-35. To study the role of IL-35 in immune responses, murine recombinant IL-35 was cloned and expressed in a mammalian GS system to produce sufficient quantities. IL-35 induced proliferation of murine CD4+CD25+ and CD4+CD25- T cells when stimulated with immobilized anti-CD3 and anti-CD28 antibodies in vitro. The IL-35-expanded CD4+CD25+ T cell population expressed Foxp3 and produced elevated levels of IL-10, whereas the IL-35-induced CD4+CD25- T cells produced IFN-γ but not IL-4. The IL-35-expanded CD4+CD25+ T cells maintained their suppressive functions against CD4+CD25- effector cells. Furthermore, when cultured with soluble anti-CD3 and antigen-presenting cells, IL-35 directly suppressed the proliferation of CD4+CD25- effector cells. Moreover, IL-35 inhibited the differentiation of Th17 cells in vitro. In vivo, IL-35 effectively suppressed established collagen-induced arthritis in mice with the suppression of IL-17 production but enhanced IFN-γ synthesis. Therefore, IL-35 is a novel cytokine suppressing the immune response through the expansion of regulatory T cells and suppression of Th17 cell development. For the future study of human IL-35, human EBI3 and p35 were cloned and linked together with an Fc fusion part. Human IL-35 was expressed in GS system and the function of the recombinant protein needs further study. These data in this thesis provide direct evidence that IL-27 and IL-35 are important mediators in murine collagen-induced arthritis disease. This implicated that IL-27 and IL-35 could represent potential new targets for novel therapeutic agents in human RA. However, the findings on the dual role of IL-27 at the different disease process suggested that the involvement of IL-27 in the pathogenesis of human RA should be carefully investigated before clinical therapy application.
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Preedy, Emily Callard. "Interfacial phenomena between bacterial or mammalian cells and orthopaedic biomaterials." Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/80763/.
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Adhesion as a scientific phenomenon has been researched for the past 70 years, as the notion of two entities contacting effects a huge expanse of daily activities, from writing to sophisticated cellular and bacterial interactions essential for growth and survival. Inherently, a robust and adequate model of adhesion was acquired, one in which biological aspects were considered. Initially, the methodology required was optimised using the atomic force microscope (AFM) by testing a model bone substrate against ultra-high molecular weight polyethylene (UHMWPE), a material commonly found in the articulating acetabular cup. Once a force mapping technique was established experimentation continued to bacterial adhesion against model bone samples of various roughness, establishing that the adhesion phenomena occurs at a scale dependency due to the alterations in the topography of the surface at the micro to nano level. Aseptic loosening and osteolysis are major causes of failures in implanted biomedical devices at the hip. These issues are governed by the deterioration of the moving components, producing particles known as wear debris associated with the metals, bone cement, and UHMWPE materials initiating an immune response which is detrimental to the surrounding cells and tissues adjacent to the implant. The notion of mechanical aspects altering the health of mammalian cells has been ignored throughout the research of implantations and their effect on the cells by foreign bodies; the only concept studied to date is the viability and functionality post exposure. Therefore, this thesis aims at observing ii mesenchymal and osteoblast (both rodent and human) cells associated to wear debris (metal and polymeric particles of various sizes and compositions) exposure and the effect this has on cell nanomechanical and adhesive properties using the AFM techniques. The data obtained indicated that Cobalt nanoparticles were more damaging on all cell types than Titanium and polymeric particles.
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Revie, John. "Identification and characterisation of telomere regulatory and signalling pathways after induction of telomere dysfunction." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7358/.
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Telomeres are DNA-protein complexes which cap the ends of eukaryotic linear chromosomes. In normal somatic cells telomeres shorten and become dysfunctional during ageing due to the DNA end replication problem. This leads to activation of signalling pathways that lead to cellular senescence and apoptosis. However, cancer cells typically bypass this barrier to immortalisation in order to proliferate indefinitely. Therefore enhancing our understanding of telomere dysfunction and pathways involved in regulation of the process is essential. However, the pathways involved are highly complex and involve interaction between a wide range of biological processes. Therefore understanding how telomerase dysfunction is regulated is a challenging task and requires a systems biology approach. In this study I have developed a novel methodology for visualisation and analysis of gene lists focusing on the network level rather than individual or small lists of genes. Application of this methodology to an expression data set and a gene methylation data set allowed me to enhance my understanding of the biology underlying a senescence inducing drug and the process of immortalisation respectively. I then used the methodology to compare the effect of genetic background on induction of telomere uncapping. Telomere uncapping was induced in HCT116 WT, p21-/- and p53-/- cells using a viral vector expressing a mutant variant of hTR, the telomerase RNA template. p21-/- cells showed enhanced sensitivity to telomere uncapping. Analysis of a candidate pathway, Mismatch Repair, revealed a role for the process in response to telomere uncapping and that induction of the pathway was p21 dependent. The methodology was then applied to analysis of the telomerase inhibitor GRN163L and synergistic effects of hypoglycaemia with this drug. HCT116 cells were resistant to GRN163L treatment. However, under hypoglycaemic conditions the dose required for ablation of telomerase activity was reduced significantly and telomere shortening was enhanced. Overall this new methodology has allowed our group and collaborators to identify new biology and improve our understanding of processes regulating telomere dysfunction.
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Alghamdi, Jahad. "Epidemiology and genetic architecture of blood pressure : a family based study of generation Scotland." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7540/.
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Hypertension is a major risk factor for cardiovascular disease and mortality, and a growing global public health concern, with up to one-third of the world’s population affected. Despite the vast amount of evidence for the benefits of blood pressure (BP) lowering accumulated to date, elevated BP is still the leading risk factor for disease and disability worldwide. It is well established that hypertension and BP are common complex traits, where multiple genetic and environmental factors contribute to BP variation. Furthermore, family and twin studies confirmed the genetic component of BP, with a heritability estimate in the range of 30-50%. Contemporary genomic tools enabling the genotyping of millions of genetic variants across the human genome in an efficient, reliable, and cost-effective manner, has transformed hypertension genetics research. This is accompanied by the presence of international consortia that have offered unprecedentedly large sample sizes for genome-wide association studies (GWASs). While GWAS for hypertension and BP have identified more than 60 loci, variants in these loci are associated with modest effects on BP and in aggregate can explain less than 3% of the variance in BP. The aims of this thesis are to study the genetic and environmental factors that influence BP and hypertension traits in the Scottish population, by performing several genetic epidemiological analyses. In the first part of this thesis, it aims to study the burden of hypertension in the Scottish population, along with assessing the familial aggregation and heritialbity of BP and hypertension traits. In the second part, it aims to validate the association of common SNPs reported in the large GWAS and to estimate the variance explained by these variants. In this thesis, comprehensive genetic epidemiology analyses were performed on Generation Scotland: Scottish Family Health Study (GS:SFHS), one of the largest population-based family design studies. The availability of clinical, biological samples, self-reported information, and medical records for study participants has allowed several assessments to be performed to evaluate factors that influence BP variation in the Scottish population. Of the 20,753 subjects genotyped in the study, a total of 18,470 individuals (grouped into 7,025 extended families) passed the stringent quality control (QC) criteria and were available for all subsequent analysis. Based on the BP-lowering treatment exposure sources, subjects were further classified into two groups. First, subjects with both a self-reported medications (SRMs) history and electronic-prescription records (EPRs; n =12,347); second, all the subjects with at least one medication history source (n =18,470). In the first group, the analysis showed a good concordance between SRMs and EPRs (kappa =71%), indicating that SRMs can be used as a surrogate to assess the exposure to BP-lowering medication in GS:SFHS participants. Although both sources suffer from some limitations, SRMs can be considered the best available source to estimate the drug exposure history in those without EPRs. The prevalence of hypertension was 40.8% with higher prevalence in men (46.3%) compared to women (35.8%). The prevalence of awareness, treatment and controlled hypertension as defined by the study definition were 25.3%, 31.2%, and 54.3%, respectively. These findings are lower than similar reported studies in other populations, with the exception of controlled hypertension prevalence, which can be considered better than other populations. Odds of hypertension were higher in men, obese or overweight individuals, people with a parental history of hypertension, and those living in the most deprived area of Scotland. On the other hand, deprivation was associated with higher odds of treatment, awareness and controlled hypertension, suggesting that people living in the most deprived area may have been receiving better quality of care, or have higher comorbidity levels requiring greater engagement with doctors. These findings highlight the need for further work to improve hypertension management in Scotland. The family design of GS:SFHS has allowed family-based analysis to be performed to assess the familial aggregation and heritability of BP and hypertension traits. The familial correlation of BP traits ranged from 0.07 to 0.20, and from 0.18 to 0.34 for parent-offspring pairs and sibling pairs, respectively. A higher correlation of BP traits was observed among first-degree relatives than other types of relative pairs. A variance-component model that was adjusted for sex, body mass index (BMI), age, and age-squared was used to estimate heritability of BP traits, which ranged from 24% to 32% with pulse pressure (PP) having the lowest estimates. The genetic correlation between BP traits showed a high correlation between systolic (SBP), diastolic (DBP) and mean arterial pressure (MAP) (G: 81% to 94%), but lower correlations with PP (G: 22% to 78%). The sibling recurrence risk ratio (λS) for hypertension and treatment were calculated as 1.60 and 2.04 respectively. These findings confirm the genetic components of BP traits in GS:SFHS, and justify further work to investigate genetic determinants of BP. Genetic variants reported in the recent large GWAS of BP traits were selected for genotyping in GS:SFHS using a custom designed TaqMan® OpenArray®. The genotyping plate included 44 single nucleotide polymorphisms (SNPs) that have been previously reported to be associated with BP or hypertension at genome-wide significance level. A linear mixed model that is adjusted for age, age-squared, sex, and BMI was used to test for the association between the genetic variants and BP traits. Of the 43 variants that passed the QC, 11 variants showed statistically significant association with at least one BP trait. The phenotypic variance explained by these variant for the four BP traits were 1.4%, 1.5%, 1.6%, and 0.8% for SBP, DBP, MAP, and PP, respectively. The association of genetic risk score (GRS) that were constructed from selected variants has showed a positive association with BP level and hypertension prevalence, with an average effect of one mmHg increase with each 0.80 unit increases in the GRS across the different BP traits. The impact of BP-lowering medication on the genetic association study for BP traits has been established, with typical practice of adding a fixed value (i.e. 15/10 mmHg) to the measured BP values to adjust for BP treatment. Using the subset of participants with the two treatment exposure sources (i.e. SRMs and EPRs), the influence of using either source to justify the addition of fixed values in SNP association signal was analysed. BP phenotypes derived from EPRs were considered the true phenotypes, and those derived from SRMs were considered less accurate, with some phenotypic noise. Comparing SNPs association signals between the four BP traits in the two model derived from the different adjustments showed that MAP was the least impacted by the phenotypic noise. This was suggested by identifying the same overlapped significant SNPs for the two models in the case of MAP, while other BP traits had some discrepancy between the two sources.
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Aldlgan, Abdulaziz. "Chromatographic analysis and survey studies to evaluate the emerging drugs of synthetic cannabinoids in Scotland and Saudi Arabia." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7579/.
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Synthetic cannabinoid receptor agonists or more commonly known as synthetic cannabinoids (SCs) were originally created to obtain the medicinal value of THC but they are an emerging social problem. SCs are mostly produced coated on herbal materials or in powder form and marketed under a variety of brand names, e.g. “Spice”, “K2”. Despite many SCs becoming controlled under drug legislation, many of them remain legal in some countries around the world. In Scotland, SCs are controlled under the Misuse of Drugs Act 1971 and Psychoactive Substances Act 2016 that only cover a few early SCs. In Saudi Arabia, even fewer are controlled. The picture of the SCs-problem in Scotland is vague due to insufficient prevalence data, particularly that using biological samples. Whilst there is evidence of increasing use of SCs throughout the world, in Saudi Arabia, there is currently no data regarding the use of products containing SCs among Saudi people. Several studies indicate that SCs may cause serious toxicity and impairment to health therefore it is important to understand the scale of use within society. A simple and sensitive method was developed for the simultaneous analysis of 10 parent SCs (JWH-018, JWH-073, JWH-250, JWH-200, AM-1248, UR-144, A-796260, AB-FUBINACA, 5F-AKB-48 and 5F-PB-22) in whole blood and 8 corresponding metabolites (JWH-018 4-OH pentyl, JWH-073 3-OH butyl, JWH-250 4-OH pentyl, AM-2201 4-OH pentyl, JWH-122 5-OH pentyl, JWH-210 5-OH pentyl, 5F-AKB-48 (N-4 OH pentyl), 5F-PB-22 3-carboxyindole)in urine using LLE and LC-MS/MS. The method was validated according to the standard practices for method validation in forensic toxicology (SWGTOX, May 2013). All analytes gave acceptable precision, linearity and recovery for analysing blood and urine samples. The method was applied to 1,496 biological samples, a mixture of whole blood and urine. Blood and/or urine samples were analysed from 114 patients presenting at Accident and Emergency in Glasgow Royal Infirmary, in spring 2014 and JuneDecember 2015. 5F-AKB-48, 5F-PB-22 and MDMB-CHMICA were detected in 9, 7 and 9 cases respectively. 904 urine samples from individuals admitted to/liberated from Scottish prisons over November 2013 were tested for the presence of SCs. 5F-AKB-48 (N-4 OH pentyl) was detected in 10 cases and 5F-PB-22 3-carboxyindole in 3 cases. Blood and urine samples from two post-mortem cases in Scotland with suspected ingestion of SCs were analysed. Both cases were confirmed positive for 5F-AKB-48. A total of 463 urine samples were collected from personnel who presented to the Security Forces Hospital in Ryiadh for workplace drug testing as a requirement for their job during July 2014. The results of the analysis found 2 samples to be positive for 5F-PB-22 3carboxyindole. A further study in Saudi Arabia using a questionnaire was carried out among 3 subpopulations: medical professionals, members of the public in and around smoking cafes and known drug users. With regards to general awareness of Spice products, 16%, 11% and 22% of those participants of medical professionals, members of the public in and around smoking cafes and known drug users, respectively, were aware of the existence of SCs or Spice products. The respondents had an overall average of 4.5% who had a friend who used these Spice products. It is clear from the results obtained in both blood and urine testing and surveys that SCs are being used in both Scotland and Saudi Arabia. The extent of their use is not clear and the data presented here is an initial look into their prevalence. Blood and urine findings suggest changing trends in SC use, moving away from JWH and AM SCs to the newer 5F-AKB-48, 5-F-PB-22 and MDMBCHMICA compounds worldwide. In both countries 5F-PB-22 was detected. These findings clarify how the SCs phenomenon is a worldwide problem and how the information of every country regarding what SCs are seized can help and is not specific for that country. The analytes included in the method were selected due to their apparent availability in both countries, however it is possible that some newer analytes have been used and these would not have been detected. For this reason it is important that methods for testing SCs are updated regularly and evolve with the ever-changing availability of these drugs worldwide. In addition, there is little published literature regarding the concentrations of these drugs found in blood and urine samples and this work goes some way towards understanding these.
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Sagan, Ewelina Nina. "The influence of P2Y12 antagonists on vascular NO signalling." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/48547/.
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P2Y12 antagonists are pharmacological agents used clinically in advanced stages of coronary artery disease in order to inhibit ADP-induced activation and aggregation of platelets and prevent deadly thrombotic events. Of the orally-prescribed P2Y12 antagonists available clopidogrel is the most established, it exhibits an excellent safety track record and is a popular drug, and was accredited for years the second-best selling drug in the world. However, since clopidogrel was introduced to the market in 1997 many pleiotropic effects have been noticed, which suggest other off-target yet beneficial effects in addition to its anti-platelet effects. The overall hypothesis being tested in this body of work was that P2Y12 antagonists, clopidogrel in particular, have the positive influence on vascular NO signalling. A vascular model was set up using isolated rabbit aortae in which clopidogrel enhanced NO donor-induced vasorelaxation. Although the precise mechanism was not found, the effect was independent of P2Y12 receptors and possibly linked to decreased superoxide production and improved anti-oxidant/inflammatory status in vessels. This finding might be relevant for patients receiving concomitant therapy with organic nitrates and clopidogrel. In vitro studies revealed novel S-nitrosation properties of P2Y12 antagonists, surprisingly without the need for metabolism to their active form. Newly synthesized SNO derivatives of clopidogrel and prasugrel were more potent in inhibition of platelet aggregation and induction of vasodilation than their parental forms. Although the formation of drug-SNO species has to be confirmed in vivo, they have a potential to increase NO bioavailability in patients. Clopidogrel administration to coronary artery disease patients resulted in upregulated plasma levels of nitrite and cGMP after 2 h-intake of a loading dose, which were further increased after 3 days of a maintenance therapy. This effect was never shown before in man and most likely reflects improved endogenous NO production, but also providing additional protection from the effects of nitrite at the same time. Taken together, the results of this thesis clearly demonstrate the influence of clopidogrel on vascular response to NO as well as NO production, metabolism and bioavailability. It is important to identify these alternative pathways especially in the current era with alternative P2Y12 antagonists that overcome some of the limitations of clopidogrel but may not share all the beneficial properties.
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Docherty, Louise E. "Identification and characterisation of novel small RNAs from repetitive elements in mammals." Thesis, University of Glasgow, 2007. http://theses.gla.ac.uk/16/.
Full textAbstract:
Transposable elements account for the almost half of the sequence encoded by mammalian genomes, which become silenced during early embryonic development. This thesis sought to explore the hypothesis of the involvement of the RNAi pathway in the silencing of transposable elements in mammals, predominantly through the identification of transposon-associated RNA of -20-25nt using a gel blotting technique. Initially cell lines of embryonic and tumour origin were analysed. This lead to the identification of several previously unreported transposon-associated RNA ranging from 70-90nt. However, it was not until a more detailed analysis of the embryonic cell lines, with the induction of differentiation in cell culture that several discrete RNA of -20nt were detected for the mouse transposons L1 and B2. The differentiation of embryonic cell lines in culture also serendipitously lead to the detection of several short 55 rRNA of -22-26nt, these were also later detected in several human cell lines of breast cancer origin and healthy breast tissue. Intriguingly the -20-26nt repeat-associated identified were predominantly observed after two-days of differentiation in cell culture in several cell lines and often coincided with an ethidium bromide stainable band of -19nt. The latter may indicate a large proportion of these RNAs. Further analysis of the B2 and 55 rRNA repeat-associated short RNA revealed both to have reduce accumulation in Dicer-null embryonic stem cells, implicating a possible association with a known component of the RNAi pathway. Dicer was also observed to process the longer -50-80nt 55rRNA to -20-26nt in vitro. BLAST was also used to identify possible mRNA targets for the short B2 and 55 rRNA. One of these, the mRNA encoding sialic acid acetylesterase (SIAE) was consistently observed to be reduced with the accumulation of the short RNA using end-point RT-PCR, consistent with targeting through the RNAi or a similar pathway. However, no further links with the RNAi pathway were established, with no targeting detected for the short B2 or 55 rRNA using dual luciferase sensor assays. The repeat-associated RNA identified in this thesis are among the first of their type and further work will be required to establish what relevance they have to the RNAi pathway and transposon regulation.
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Spears, Mark. "Reduced corticosteroid sensitivity in smokers with asthma : potential mechanisms and treatment." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/1100/.
Full textAbstract:
Smokers with asthma display reduced responses to both inhaled and oral corticosteroids with associated increased symptoms, accelerated decline in lung function and increased use of health care services. Little work has been undertaken to address the possible causes of this reduced response and to find effective replacement therapies. Therefore this thesis was carried out with the aim of identifying potential mechanisms and new therapies for this group. The oral bronchodilator theophylline has been suggested as a treatment for corticosteroid insensitivity due to its ability to increase HDAC activity in-vitro. I undertook an exploratory proof of concept clinical trial based on the hypothesis that low dose theophylline would restore corticosteroid sensitivity in smokers with asthma through theophylline induced recovery of HDAC activity. Low dose oral theophylline added to inhaled corticosteroid increased pre-bronchodilator lung function and reduced symptoms of asthma whilst low dose theophylline given alone reduced symptoms but had no effect on pre-bronchodilator lung function. This research provides a foundation for future studies designed to examine the efficacy of theophylline in smokers with asthma. Agonists of the nuclear hormone receptor peroxisome proliferator activated receptor-γ (PPARγ) have been demonstrated to be effective at reducing inflammation in both in-vitro and animal models of asthma. Therefore to examine the hypothesis that PPARγ stimulation would reduce the inflammation present in smokers with asthma I undertook an exploratory, proof of concept clinical trial using the PPARγ agonist rosiglitazone. Treatment with rosiglitazone was associated with a trend to improvement in FEV1 and improvement in a marker of small airway lung function and as such may provide an alternative treatment for small airways obstruction in conditions such as asthma and chronic obstructive airways disease. This trial will enable powering of future confirmatory studies. Altered cytokine profiles, specifically the combination of increased interleukin (IL)-2 and 4, are observed in asthmatic subjects with corticosteroid insensitivity. Based on this work I examined the hypothesis that the altered response to corticosteroids in smokers with asthma was associated with an altered cytokine milieu including raised levels of IL-2 and 4. Smokers with asthma, characterised as corticosteroid resistant by oral corticosteroid trial, demonstrated significantly raised sputum supernatant IL-6 levels and raised levels of a number of other sputum cytokines compared to non smokers with asthma. This altered phenotype suggests cigarette smoking in asthma may be associated with a deviation to Th1 mediated inflammation and could provide an explanation for the reduced corticosteroid response of smokers with asthma. The cell type/s responsible for both this shift in immunological phenotype and production of increased levels of sputum cytokines is unclear and will require further study. Previous in-vitro and in-vivo research has identified altered histone acetylation patterns in subjects with relative corticosteroid resistance. Therefore I examined the hypothesis that smokers with asthma displayed reduced responses to corticosteroids as a result of a cigarette smoke induced reduction in histone de-acetylase (HDAC) activity. Smokers with asthma provided sputum macrophages and blood for peripheral blood borne monocytes to examine total HDAC activity. Sputum and blood macrophage total HDAC activity was equivalent in smokers and non-smokers with asthma. Therefore reduced blood total HDAC activity does not appear to explain the altered corticosteroid response in this group. However the number of sputum macrophages obtained may have been too low to allow conclusive examination of this endpoint. Another consideration is that contamination of the sample due to the technique used may be altering the signal obtained. Further work either through modification of sputum induction techniques to increase macrophage number or bronchoscopic sampling is required to conclusively address the role of alveolar macrophage HDAC activity in the reduced corticosteroid response displayed by smokers with asthma. Exhaled nitric oxide has been exploited as a useful exploratory and confirmatory endpoint in asthma. However exhaled nitric oxide, measured using standard flow rates and methodology, is unhelpful in smokers with asthma as cigarette smoking is associated with a marked reduction in exhaled nitric oxide levels in the majority of subjects. Recent research has demonstrated that measurement of exhaled nitric oxide at multiple flow rates followed by mathematical modelling reveals increased levels of alveolar nitric oxide that were unaltered by current smoking. Therefore to examine the hypothesis that smokers with asthma display altered levels of alveolar nitric oxide and flow independent parameters compared to non-smokers with asthma I carried out a cross-sectional study. Alveolar nitric oxide, determined by linear modelling, was significantly reduced in smokers with asthma compared to non smokers with asthma. The concentrations observed were within the range for normal subjects and therefore this method does not overcome the problems inherent in measuring exhaled nitric oxide at standard flows. The use of non-linear modelling did demonstrate parity between smokers and non-smokers with asthma for alveolar nitric oxide. Nitric oxide flux was lower in smokers with asthma when derived by both linear and non-linear modelling and displayed sensitivity to oral corticosteroids. Therefore nitric oxide flux is worthy of further investigation as an exploratory endpoint in smokers with asthma. In conclusion treatment of smokers with asthma with low dose theophylline alone, the combination of low dose theophylline and inhaled corticosteroid and the PPARγ agonist rosiglitazone was associated with clinical improvements and further clinical trials to assess the role for these treatments in the management of smokers with asthma are justified. Smokers with asthma display an altered sputum cytokine profile with raised levels of the proinflammatory cytokine IL-6, equivalent blood total HDAC activity and reduced alveolar nitric oxide compared to non-smokers with asthma. Sputum HDAC activity requires further development before it can be confidently employed as a method of assessing total pulmonary HDAC activity.
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Stephen, Linda J. "Antiepileptic drugs - treating populations." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/2005/.
Full textAbstract:
Epilepsy affects 50 million people world-wide. Since 1982, the Western Infirmary Epilepsy Unit has provided a specialist service for over 6900 people with suspected and established seizure disorders. The twelve studies detailed in this thesis discuss the management of epilepsy in different patient populations, and explore beneficial and adverse effects of antiepileptic drugs (AEDs). AED development has allowed advances in pharmacological treatment of localisation-related epilepsies. Thus, outcomes were investigated in 550 such patients followed-up at the epilepsy clinic over 13 years (Paper i). Of these, 312 (57%) became seizure-free on medication. Those with hippocampal sclerosis had the poorest outcome (p<0.01), and a higher incidence of febrile convulsions (p<0.001). Although many patients benefited from AED therapy, results may be biased, given this cross-sectional study analysed data from both newly diagnosed patients, and those with drug-resistant seizures. Many people with epilepsy take more than one AED, although supportive evidence is sparse. Hence, polytherapy outcomes in 2881 patients registered with the Epilepsy Unit database were examined (Paper ii). Of these, 1617 (56%) were seizure-free, with 332 (21%) taking more than one AED (287 on two, 86%; 42 on three, 13%; 3 on four, 1%). There were 40 duotherapy and 28 triple therapy combinations resulting in seizure freedom. Therefore, combining two or three, but rarely four AEDs may be useful for patients not responding to monotherapy. Because this was a retrospective analysis of newly treated patients and those with refractory epilepsy, the analysis was subject to bias. Lack of a control group was also a weakness. Epilepsy Unit staff are therefore now examining similar outcomes in a large population of newly treated patients only. To establish the place of recently marketed AEDs in clinical practice, four studies examined prospectively the efficacy and tolerability of the novel agent, topiramate, in uncontrolled epilepsy. Adjunctive topiramate was administered in 170 patients with refractory seizures (Paper iii). Seizure frequency and adverse events were monitored. Patients were followed-up until seizure freedom for ≥ 6 months, ≥ 50% or <50% seizure reduction, intolerable side-effects, or lack of efficacy occurred. Seizure freedom was achieved in 39 (23%) patients. A ≥50% reduction in seizure frequency was reported in 80 (47%) others. Doses were often lower than those in regulatory studies. Efficacy as monotherapy was also demonstrated. Using the same end-points, topiramate was added to AED regimens of 64 patients with learning disabilities and epilepsy (Paper iv). Remission from seizures was established in 16 (25%). In similar fashion, levetiracetam was started in 156 patients with uncontrolled epilepsy (Paper v). Of these, 40 (26%) became seizure-free, many on low doses. When the drug was added to AED regimens in 64 patients with learning disabilities, 24 (38%) became seizure-free for at least 6 months (Paper vi). Caregiver quality-of-life scores improved significantly with levetiracetam (p<0.001). It is important to recognise that for all four audits results may be biased due to their observational nature, and the fact that they were undertaken at a single centre, with no control group. For patients with learning disabilities, small numbers, and retrospective baseline recordings for some could also have introduced bias. In Papers vii, viii and ix, findings from longitudinal studies in teenagers, people with learning disabilities and epilepsy, and newly diagnosed elderly patients attending the Epilepsy Unit, are reported. At the Teenager Clinic, 301 adolescents were reviewed over four years (Paper vii). Epilepsy was excluded in 135 (45%), five taking AEDs. A single seizure occurred in 22 others. In the 144 with epilepsy, seizure freedom for ≥ 12 months was attained in 76 (53%), but outcomes were poorer than expected. Neuroimaging was abnormal in 27 (43%). Newly diagnosed patients fared better than those taking treatment (p<0.05). More teenagers with primary generalised seizures (60%) attained remission, compared to those with focal-onset seizures (46%) (p<0.02). The retrospective natures of the analysis, and lack of control group may have biased results, thus making statistical conclusions inaccurate. Findings suggested the need for improved services. Over four years, 214 patients with learning disabilities and refractory epilepsy were followed-up (Paper viii). Although it is generally thought these individuals’ seizures are difficult to control, 59 (43%) became seizure-free for ≥ 12 months with AEDs. There was no change in quality-of-life scoring during this time, and no relationship between extent of learning disability and seizure control. The observational nature of the audit, and lack of control group may have biased results. Currently, there are few data on elderly people with epilepsy. Thus, outcomes over a 20-year period in 117 newly diagnosed senior citizens were examined (Paper ix). After starting AED treatment, 93 (79%) became seizure-free for ≥ 12 months, 73 (62%) with their first drug. Prognosis was better than in younger patients, and for those with fewer pre-treatment seizures (p=0.0078). Again bias may have been introduced because of the study’s observational nature and lack of control group. The final studies concentrate on AED-related adverse effects (Papers x, xi and xii). Bone changes have been reported with AED use. Hence, the relationship between bone mineral density, and long-term AED treatment in 78 older adults (47 post-menopausal women, 31 men), taking hepatic enzyme-inducing or non-inducing AEDs, was explored in a case-controlled study (Paper x). Men had significantly lower bone mineral density than controls at the lumbar spine (p<0.01), and neck of femur (p<0.005). Women had statistically reduced bone mineral density at the femoral neck (p<0.05). It was concluded that long-term AED treatment is an independent risk factor for reduced bone mineral density in people with epilepsy. As sodium valproate may be associated with metabolic changes and polycystic ovarian syndrome, hormone profiles were compared in 76 young men and women taking sodium valproate or lamotrigine monotherapy, to assess whether a pharmacological effect of valproate was responsible (Paper xi). Results revealed only four obese females exhibiting biochemical characteristics of polycystic ovarian syndrome (p=0.05), with obese patients of both sexes (p=0.01), and valproate-treated men (p=0.03) having higher insulin concentrations. Results are not significant when corrected for multiple comparisons. It can therefore be concluded that no differences in metabolic indices between patients taking sodium valproate or lamotrigine existed. To examine further effects on androgenic hormones, and the efficacy and tolerability of sodium valproate and lamotrigine monotherapy, a randomised, prospective study in 225 patients was performed (Paper xii). Patients were recruited if they presented with a minimum of two unprovoked seizures of any type, or a single seizure and underlying neuropathology. Of patients with partial-onset seizures, 81 received sodium valproate and 80 were randomised to receive lamotrigine. Of those with idiopathic generalised epilepsies, 30 received sodium valproate and 34 took lamotrigine. Seizure-free rates were identical in both arms at twelve months between the valproate and lamotrigine cohorts. There was a trend towards superiority for valproate (57% seizure-free) over lamotrigine (35% seizure-free) for patients with idiopathic generalised epilepsies (p=0.09), but a converse separation of outcomes for localisation-related epilepsies (43% seizure-free with valproate, 53% seizure-free with lamotrigine, p=0.24). More patients taking sodium valproate withdrew due to adverse events (p=0.046), eight because of weight gain.
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Hamilton, Ashley. "Investigation into the relevance of BCR-ABL for the survival of cancer stem cells in chronic myeloid leukaemia." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/2208/.
Full textAbstract:
Chronic myeloid leukaemia (CML) is a clonal myeloproliferative disorder of the haemopoietic stem cell, defined by the Philadelphia chromosome (Ph) - the outcome of a balanced, reciprocal translocation between the long arms of chromosomes 9 and 22. The novel fusion oncogene generated on chromosome 22 as a result of this translocation is called BCR-ABL. In the majority of patients, this oncogene transcribes a 210-kDa constitutively active protein tyrosine kinase, often referred to as p210BCR-ABL, which is necessary for the transformation of the disease. The introduction of the orally available, tyrosine kinase inhibitor (TKI) - imatinib mesylate (IM) - marked a major advance in CML treatment in terms of efficacy and tolerability and has now become the first line of therapy. IM acts by competing with ATP to block ABL-kinase activity, resulting in the selective apoptosis induction of BCR-ABL+ cells. However, despite the success of IM as standard therapy for CML, only a small proportion of patients obtain a complete molecular response, where they become negative for BCR-ABL transcripts by RTPCR. It is hypothesised that this minimal residual disease is the result of a primitive quiescent subpopulation of leukaemic cells, which may be the cause for relapse at a later date. Another major clinical concern is the observation of molecular resistance in IM-treated patients. Proposed mechanisms of resistance include BCR-ABL amplification, decreased intracellular IM concentrations caused by drug efflux proteins such as multi drug resistance-1 and the development of point mutations within the ABL-kinase domain. In an attempt to overcome IMresistance, a second generation of BCR-ABL inhibitors has been developed. Dasatinib (BMS-354825, Sprycel) is a TKI developed for the treatment of IM resistant or -intolerant patients with Ph+ leukaemias, which has a 325-fold greater potency than IM against cells expressing wild-type BCR-ABL, and is effective against all IM-resistant BCR-ABL mutants tested in vitro, except T315I. Previously, we showed that dasatinib induced durable inhibition of BCR-ABL and impressive clearance of Ph+ cells, however, the primitive quiescent cell population did not appear to undergo apoptosis even after several days TKI exposure. Therefore, it was still not clear whether early CML progenitor cells depend on BCR-ABL for their growth and survival. In this study we have attempted to determine whether CML stem cells are dependent on BCR-ABL TK activity for their survival and/or proliferation using dasatinib treatment and aimed to characterise the cells which survived drug exposure. We found that 10% of the CML cells were able to survive the dasatinib treatment. We also showed that maximal BCR-ABL TK inhibition was achieved in the surviving CML cells, both in the bulk population of cells and the more problematic primitive stem cell population. Those cells which survived the dasatinib treatment were found to be primitive, residing mainly in the undivided cell fraction and the very early cell divisions. Since these BCR-ABL TK-inhibited, resistant cells were also able to grow when re-cultured in cytokines and form longterm culture-initiating cell (LTC-IC) colonies; these data suggested that ~10% of primitive CD34+ CML cells are not addicted to BCR-ABL TK activity for their survival. This also suggested that these primitive, resistant CML cells appeared to survive and proliferate by BCR-ABL-independent mechanisms. Therefore, the next experiments were then designed to investigate the cellular process of autophagy as a potential means of primitive CML cell survival. Analysis of the properties of CD34+ CML cells which remained viable following dasatinib treatment, revealed the existence of cytoplasmic autophagic structures determined by electron microscopy and significantly increased autophagosome-asociated LC3-II, particularly in the cells cultured without growth factors (GF)s. This suggested that autophagy is induced following GF deprivation of CML cells and is significantly increased within these cells, upon BCR-ABL inhibition following dasatinib treatment. Furthermore, we also found that the inhibition of autophagy greatly potentiated the effect of TKI treatment on the reduction of primitive CML progenitor cells, in terms of the effective eradication of functionally defined colony forming cells and LTC-ICs. Overall, this thesis has shown for the first time that the most TKI-resistant primitive CML cells are likely to be independent of BCR-ABL TK activity for their proliferation and/or survival. Furthermore, we have shown that these resistant CML stem cells rely on the BCR-ABL independent autophagy process for survival in response to stressful conditions, such as, GF deprivation and TKI treatment.
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Watt, Jonathan. "Targeting oxidative stress after percutaneous coronary intervention." Thesis, University of Glasgow, 2011. http://theses.gla.ac.uk/2877/.
Full textAbstract:
Percutaneous coronary intervention (PCI) improves the blood supply to the heart by unblocking narrowed coronary arteries. Implantation of a coronary stent is usually required to scaffold the artery and improve long-term vessel patency. Drug-eluting stents (DES) have been developed to decrease the incidence of stent renarrowing, known as in-stent restenosis (ISR), the main limitation of bare metal stents (BMS). DES release potent drugs into the artery wall to inhibit cell division and attenuate ISR. However, this strategy can also impair vascular healing and increase the risk of stent thrombosis, which is a serious concern. Novel approaches to this problem are urgently required. Oxidative stress reflects a state in which reactive oxygen species (ROS) prevail over antioxidant defences. PCI causes a major release of ROS from the injured artery wall and these molecules appear to play an important role in critical signalling pathways involved in vascular repair. Numerous animal studies have found that oral antioxidants may reduce ISR and improve healing, yet these strategies have not been effective in humans. Stent-based delivery of antioxidants may offer more efficacious, targeted protection against oxidative stress than oral administration. The role of oxidative stress in endothelial repair mediated by bone marrow-derived endothelial progenitor cells (EPCs) in patients with coronary heart disease is also poorly defined. The main aims of this thesis were: to determine the in vitro effects of oxidative stress on key aspects of thrombosis and vascular healing; to evaluate a novel antioxidant-eluting stent in an in vivo porcine model; and to examine the relationship between oxidised low-density lipoprotein (oxLDL), EPCs and coronary endothelial function in patients with stable angina. Oxidative stress, generated by the xanthine/xanthine oxidase reaction, inhibited whole blood aggregation in a concentration-dependent fashion. This was probably due to an excess of ROS which impaired, rather than stimulated, thrombosis. Healthy endothelial cells (ECs) also inhibited whole blood aggregation, but this was not mitigated by oxidative stress. EC migration was assessed using an in vitro endothelial wound scratch assay. Oxidative stress was highly toxic to ECs and inhibited migratory activity. Nitrone D, a novel spin trapping antioxidant, was evaluated for its suitability as a novel DES coating. Nitrone D displayed weak antithrombotic effects, but markedly inhibited EC migration. Nitrone D was therefore unsuitable for a DES that was intended to improve re-endothelialisation. Oral probucol has established efficacy in animal models of restenosis, but not in humans. Probucol has been successfully incorporated as a dual DES coating with rapamycin in clinical trials. Succinobucol is a novel derivative of probucol with more potent antioxidant, anti-inflammatory and antiproliferative effects. A novel polymer-free succinobucol-eluting stent (SES) and succinobucol/rapamycin-eluting stent (SRES) were developed and compared to a commercially available polymer-free rapamycin-eluting stent (RES) and BMS. Pharmacokinetic studies demonstrated optimal drug elution from the SES. However, in a porcine coronary model, the SES significantly increased neointimal thickness and aggravated ISR. The RES reduced neointimal thickness non-significantly, whereas the SRES caused no difference in neointimal thickness, compared with the BMS. The SES was associated with greater inflammation and persistent fibrin deposition around the stent struts, which are signs of defective healing. There were no significant differences in endothelial regeneration between the groups. Subsequent cell culture studies found that succinobucol was toxic to ECs and smooth muscle cells. In the clinical study, circulating levels of EPCs were strongly correlated with coronary endothelial function, which is a novel finding. Plasma oxLDL levels were not correlated with EPCs or coronary endothelial function. In conclusion, ROS reflect a large array of molecules released after PCI that are multi-faceted regulators of platelets and vascular cells. As such, they represent a complex target for novel DES technologies. Excessive ROS may inhibit thrombus formation and delay re-endothelialisation. However, potent antioxidants delivered to injured arterial tissue after PCI may not necessarily encourage the physiological processes required to accelerate vascular repair. At high dose, local delivery of antioxidants may actually promote inflammation and aggravate ISR. Although oxLDL is known to induce endothelial dysfunction, it is not correlated with the number of circulating EPCs. These findings underline the complicated role of oxidative stress in vascular repair after PCI. Further studies are required to clarify whether antioxidants will ever provide advantages over existing options in the rapidly evolving field of interventional cardiology.
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Hawkins, Nathaniel Mark. "Heart failure and chronic obstructive pulmonary disease : common partners, common problems." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1574/.
Full textAbstract:
Heart failure (HF) and chronic obstructive pulmonary disease (COPD) are common partners with common problems. Both are chronic systemic disorders incurring significant morbidity and mortality. Although around one third of patients with HF have concurrent COPD,1 remarkably few reports have addressed this often ignored combination. The systematic review presented within this thesis defines the diagnostic challenges, prevalence and prognostic implications of HF with coexistent COPD. I then critically appraise the twin controversies of β-blockade in COPD and β-agonists in HF. The two are inextricably linked, each therapy exerting the reverse pharmacologic activity of the other. The evidence for symptomatic or prognostic benefit from either therapy is limited, and in the case of β-agonists adverse consequences appear more likely. A Cochrane meta-analysis concluded that long term cardioselective β-blockade is safe and well tolerated in patients with moderate to severe or reversible COPD.2 Although often cited,3 these conclusions are simply not true. Of the 20 randomised controlled trials included in the meta-analysis, 11 involved single doses and only one lasted longer than a month. The 9 ‘long term’ studies (defined as more than a single treatment dose) involved 147 young, predominantly male patients with moderate airways obstruction (mean forced expiratory volume in 1 second (FEV1) 1.8 litres). The effect on health status has never been assessed in any cohort with COPD. The long term impact of β-blockade on pulmonary function, symptoms and quality of life is therefore largely unknown. Most importantly, no study has included patients with HF. I randomised 27 patients with HF and coexistent moderate or severe COPD to receive bisoprolol or placebo, titrated to maximum tolerated dose over 4 months. Patients were elderly and predominantly male. Cardiovascular comorbidity, smoking history and pulmonary function were similar in each group (mean FEV1 1.37L vs 1.26L). There were several key findings. A reduction in FEV1 occurred after 4 months following treatment with bisoprolol compared with placebo (–70 ml vs +120 ml, p=0.01). Reversibility following inhaled β2-agonist and static lung volumes were not impaired by bisoprolol. All measures of health status exhibited a consistent non-significant improvement, including the Short Form 36 physical and mental component scores, Minnesota Living with Heart Failure Questionnaire, and Chronic Respiratory Questionnaire. The mean number of COPD exacerbations was similar in the bisoprolol and placebo groups. Although recruitment was limited, the results pose crucial questions and provide direction for larger randomised controlled trials. I analysed cross-sectional data from 61 primary care practices (377,439 patients) participating in the Scottish Continuous Morbidity Recording scheme. The prevalence of COPD in patients with HF increased year on year from 19.8% in 1999 to 23.8% in 2004. These changes may previously have been attributed to an ageing population or increasing age of presentation. However, the trend remained significant after age standardisation. A clear socioeconomic gradient was observed, with prevalence greatest in the most deprived. Consultation rates for HF or COPD in those with both conditions were greater than disease specific contact rates in patients with either condition alone. Cardiovascular comorbidity was similar in HF patients with and without COPD, despite differences in smoking history (respectively 76% vs 47%, p<0.001). This is concerning and suggests that common cardiovascular conditions are being under diagnosed (and likely under treated) in patients with HF and COPD. Although overall β-blocker prescribing increased over time, the adjusted odds of β-blocker prescription in patients with COPD was low (odds ratio 0.30 [95% CI 0.28–0.32], p<0.001). Whether the gap between patients with and without COPD is improving was previously unknown. Despite the overall improvement in beta-blocker prescribing, the relative difference in prescribing between those with and without COPD remained unchanged. By 2004, only 18% of individuals with HF and COPD were prescribed β-blockers. COPD is consistently an independent predictor of death and HF hospitalisation in patients with HF. However, the causes of increased mortality were unclear. I examined the relationship between COPD and cardiovascular outcomes in patients with myocardial infarction (MI) complicated by heart failure, left ventricular systolic dysfunction (LVSD), or both enrolled in the Valsartan in Acute Myocardial Infarction (VALIANT) trial. COPD was an independent predictor of mortality, largely due to increased non-cardiovascular (HR 1.86 [1.43–2.42]) and sudden death (HR 1.26 [1.03–1.53]). However, after multivariate adjustment COPD was not an independent predictor of atherosclerotic events (MI or stroke: HR 0.98 [0.77–1.23]). This is an important finding, as atherosclerotic consequences of chronic systemic inflammation in COPD have been postulated. These appear of limited clinical significance, at least during intermediate follow-up. Part of the adverse risk associated with COPD may be attributable to bronchodilators. The prognosis of patients with HF prescribed bronchodilators is however ill defined. I examined the prognostic implications of bronchodilator use in patients with HF enrolled in the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM) programme. The diversity and magnitude of adverse outcomes associated with bronchodilator therapy was surprising. Bronchodilator use was associated with increased all cause mortality (HR 1.26 [1.09–1.45]), cardiovascular death (HR 1.21 [1.03-1.42]), death due to HF progression (HR 1.40 [1.07-1.82]) and HF hospitalisation (HR 1.49 [1.29-1.72]). Although association is not causation, it is possible that bronchodilators compound maladaptive remodeling and further depress myocardial function. Finally, β-blockers were independently associated with better survival in both VALIANT and CHARM. No significant interaction was observed between either COPD or bronchodilators and β-blockade with respect to mortality. Furthermore, β-blocker use was not associated adversely with any pre-specified outcome in patients with COPD or those prescribed bronchodilators, including non-cardiovascular mortality. Although recruitment bias and the absence of spirometry limit inference to patients with severe or reversible airflow obstruction, the results should encourage β-blockade in patients with COPD. In summary, the studies presented in this thesis extend our understanding of HF with concurrent COPD. Only large randomised controlled trials will solve the quandary of β-blockers and β-agonists. Justification for these trials evolves from observational data and smaller prospective studies such as my own. In the meantime, I hope the evidence presented will stimulate physicians to re-evaluate the management of patients with HF and COPD.
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Azzopardi, Ernest Anthony. "Bioresponsive dextrin-colistin conjugates as antimicrobial agents for the treatment of Gram-negative infection." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/49662/.
Full textAbstract:
Multidrug-resistant Gram-negative infection is an important cause of mortality and morbidity. Management of these infections is often dependent upon “treatment of last resort” "small molecule" antibiotics which suffer from significant toxicity and an indiscriminate volume of distribution. The aim of this study was to develop a prototype polymer-antibiotic conjugate that may be customised by polymer modification and binding chemistry to afford selective, controlled release at an infected site. These studies employed the biodegradable, naturally-occurring polymer, dextrin, and a polymyxin antibiotic, colistin, as the first model combination. Physicochemical characterisation of a library of succinoylated dextrins and dextrin-colistin conjugates demonstrated that conjugation of dextrin to colistin was feasible and reproducible, resulting in masking of colistin's amino groups through incorporation in peptide bonds. Exposure to physiological �-amylase activity resulted in controlled degradation of the dextrin component, leading to sustained colistin release. Following exposure of the conjugates to physiological concentrations of �-amylase, minimally-modified, low molecular weight dextrin, conjugated to colistin, demonstrated significantly earlier, maximal release of colistin and subsequent reinstatement of antimicrobial activity. At maximum unmasking, the lead conjugate reported equivalent antimicrobial activity to the current clinical formulation of colistin (Colimycin®)against a range of MDR organisms including: A. baumannii, K. pneumoniae and E. coli. A static two-compartment dialysis bag model was developed under infinite sink conditions, which demonstrated that the conjugates were able to suppress bacterial growth over a significantly greater duration than colistin sulfate. Ex vivo studies of infected human wound fluid samples confirmed that colistin could be readily liberated from conjugate in infected sites. Significantly higher amylase activity in these wound fluid samples supported the notion of locally-triggered, enzymatically-mediated unmasking. An in vivo intravenous, pharmacokinetic model in rats demonstrated the increased half-life associated with conjugation and succinoylation. Moreover,the dextrin-colistin conjugates were better tolerated than colistin sulfate at higher concentrations. These studies have demonstrated the feasibility of developing this new class of “nanoantibiotics” and highlighted their potential usefulness as bioresponsive nanomedicines for the treatment of MDR Gram-negative infection.
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Al-Derwish, Omer. "Viral HSV1-TK gene, radiolabeled FIAU, and ganciclovir : combined gene targeted radiotherapy and suicide gene therapy for prostate cancer." Thesis, University of Glasgow, 2008. http://theses.gla.ac.uk/220/.
Full textAbstract:
The strategy of suicide gene therapy in cancer is based on the idea of enabling tumour cells, by gene transfer, to convert a non-toxic pro-drug into a toxic product. Previous work has shown that the combination of herpes simplex virus type 1 thymidine kinase gene (HSV1-tk) transfer with the pro-drug ganciclovir (GCV) to be a promising suicide gene therapy in cancer. Unlike several other gene therapy systems, early-phase clinical trials of this strategy have shown encouraging results. Therefore, methods to improve its therapeutic efficacy are urgently sought. The thymidine analogue 5-iodo-2’-fluoro-2’-deoxy-1-ß-D-arabino-furonosyluracil (FIAU) is an alternative substrate of the HSV1-TK enzyme. The iodine atom of FIAU can be substituted with radioactive iodine, for example; [123I]-iodine, and thereby utilised for the delivery of ionising radiation into tumour cells expressing the viral tk gene. The aim of this study was primarily to investigate the therapeutic potential of combining HSV1-tk gene transfer and [123I]FIAU for the targeted radiation cytotherapy of prostate cancer cells alone or in combination with GCV. The HSV1-tk gene was cloned into the plasmid vector pcDNA3.1. This plasmid, driven by the ubiquitous promoter of CMV, was then used to transfect the prostate cancer cell line DU145 and the glioma cell line UVW. A viral TK positive, commercially available cell line derived from osteosarcoma (143B-TK) along with its TK-negative clone were also used for comparison. The viral tk gene transfection efficiency was assessed by three independent methods. Firstly, the uptake of [123I]FIAU normalised to the uptake of tritiated thymidine ([methyl-3H]TdR); secondly, GCV sensitivity, assessed by the MTT assay; and thirdly, by the detection of HSV1-tk gene by RT-PCR. The highest specific activity of [123I]FIAU was obtained by the use of a no-carrier added method of synthesis. The cytotoxicity of [123I]FIAU was assessed by clonogenic assay after incubating monolayers of parental and TK-positive clones of the cell lines with a range of doses of [123I]FIAU for the periods of 4 h, 8 h and a period equal to their doubling times. The effect of this treatment on cell cycle progression was assessed by FACS analysis after staining the cellular DNA with propodium iodide. Combination therapy using GCV and [123I]FIAU for the treatment of TK-positive clones of the prostate cancer cell line DU-145 and the osteosarcoma cell line 143B was assessed by the method of median effect analysis and combination index. Monolayers were treated with a constant ratio of various doses of [123I]FIAU for 4h or GCV for 72h. The combination therapy followed three different timing schedules of GCV-before-[123I]FIAU, [123I]FIAU-before-GCV, or simultaneous therapy. The expression of HSV1-tk gene by the three cell lines was confirmed by the three methods described above. For instance, the TK positive clone of the cell line DU145 exhibited 4.25 ± 0.15 times higher [123I]FIAU/ [methyl-3H]TdR uptake ratio and 43 times higher sensitivity to GCV compared with the parental cell line. The three cell lines demonstrated sensitivity to radiolabelled FIAU, which was significantly enhanced by HSV1-tk gene expression. This sensitivity was time-, dose-, and proliferation-dependent. Maximum cell kill was achieved when the monolayers were exposed to [123I]FIAU for a period equavelant to the cellular doubling time. For example, the sensitivity enhancement factor by tk gene expression of the cell line DU145 increased from 5.2 to 7.6 when the treatment period was prolonged from 4 h to 26 h (doubling time of DU145). Following the treatment with [123I]FIAU for a period equal to the doubling time, cells were arrested at G2/M phase of the cell cycle. For instance, 49% of DU145-TK cells treated with 1 MBq/ml for 26 h were at G2/M phase compared with 21.9% of the untreated cells. In contrast, incubation of DU145-TK or 143B-TK cell lines with lethal doses of [123I]FIAU for 4 h and GCV for 72 h had no significant effect on cell cycle progression. Comparison of the effectiveness of [123I]FIAU in the monolayer and spheroid cultures indicated that clonogenic cell kill resulting from Auger electron bombardment was restricted to targeted rather than bystander cells. The combination therapy of [123I]FIAU and GCV of the cell line DU145-TK resulted in antagonistic effect throughout the examined dose range of the schedules of FIAU-before-GCV and simultaneous therapy and the low toxicity concentration range (lower surviving fractions) of the GCV-before-FIAU schedule. The high toxicity concentration range of the latter schedule has shown evidence of additive effect. For the osteosarcoma cell line 143B-TK, synergistic effect was observed at the high toxicity concentration range of the three combination schedules and antagonism at the low toxicity concentration range of the combinations. We concluded from this in vitro study that the combination of HSV1-tk gene transfer and the delivery of radiolabelled FIAU is a promising strategy for targeted radiation cytotherapy of prostate cancer. This proliferation-dependent therapy has caused significant cell cycle arrest that warrants further investigation. Furthermore, the combination of GCV and radiolabelled FIAU for the treatment of tumour cells expressing the gene of viral TK resulted in a dose- and schedule-dependent synergism. We believe that these encouraging results should be substantiated by in vivo experiments in the near future.
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Alyousef, Abdullah. "Identification and characterisation of lysin enzymes as potential therapeutics for the treatment of Clostridium difficile." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/49926/.
Full textAbstract:
Clostridium difficile is the most common cause of hospital acquired infections. While the current treatments of choice, antibiotics, are generally effective in promoting recovery ,the increased incidence of C. difficile infections and treatment failure associated with antibiotic resistance combined with the emergence of hypervirulent strains highlights the need to develop therapeutic approaches that specifically target the pathogen without causing collateral damage to the protective microbiota. Several non-antibiotic approaches are currently being investigated, such as bacteriophage therapy. For this reason, we attempted to isolate C. difficile specific lytic bacteriophages which could form the basis of a treatment for C. difficile. While we were unable to isolate lytic phages, we were able to isolate twelve temperate bacteriophages from twenty-three clinical isolates of C. difficile using mitomycin C. Unfortunately we failed to identify a susceptible host strain capable of supporting the replication of these phages. This failure may in part be due to repeated episodes of phage infection over time, which have resulted in the emergence of “phage resistant” species mediated by systems such as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR). Employing a PCR-based approach using primers specific for the lysin genes of five previously isolated C. difficile phages, we found evidence to suggest that repeated bacteriophage infection is a common event for clinical isolates of C. difficile. Our inability to isolate a lytic bacteriophage prompted us to adopt an alternative approach in which we used endolysin enzyme of five previously identified C. difficile phages as recombinant protein. These lysins showed broad spectrum activity against the vegetative forms of a large collection of C. difficile ribotypes with little or no activity against other species, supporting their potential as therapeutic agents. We also identified a genome associated lysin (CD630, YP_001088405), which lysed vegetative C. difficile in a similar manner to the phage derived lysins. We also cloned and expressed a spore cortex lytic enzyme (SleC) which targeted the cortex of C. difficile spores. Unfortunately this enzyme was inactive against intact spores, suggesting that the outer layers of the spore act as a permeability barrier. The results of this study showed in vitro the applicability of endolysins against the vegetative form of C. difficile and the activity of spore cortex lytic enzyme against coatless spores, offering interesting perspectives for evaluation of the antibacterial activity of a mixture of endolysin and spore cortex lytic enzyme.
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Grosset, Katherine Anne. "Therapy concordance and drug adherence in Parkinson's disease." Thesis, University of Glasgow, 2005. http://theses.gla.ac.uk/2341/.
Full textAbstract:
Chapter 1 gives an overview of the relevance of studying therapy adherence in Parkinson’s disease. Chapter 2 examines drug induced neurological syndromes and considers the validity of patients’ concerns about taking prescribed medications. Chapter 3 compares different methods of assessing therapy adherence. Chapter 4 studies factors associated with sub-optimal medicine usage in 54 patients. Chapter 5 reports a study of patient perceived involvement with management decisions and an assessment of satisfaction with the movement disorder service in 107 patients. Chapter 6 explores patients’ beliefs about antiparkinson medication in 129 patients. Chapter 7 examines the effect on Parkinson’s patients of emerging data about drug side effects, specifically fibrosis due to ergot-based dopamine agonists. Chapter 8 reports on an educational intervention designed to improve Parkinson drug timing compliance. In summary, this thesis provides important new information about medicine taking in Parkinson’s disease. A fifth of PD patients take less than 80% of prescribed antiparkinson medication. Electronic monitoring is the only reliable method of accurately detecting sub-optimal medication usage. Patients who take less than 80% of prescribed medicines are more likely to be younger, have concomitant depression, be prescribed more tablets per day and have poorer quality of life. Patients are more satisfied if they are involved in management decisions and have increased intention to comply with prescribed medication if there is better communication. Poorer quality of life is associated with less intention to comply with prescribed medication. Timing of medication intake is generally irregular but can be improved by informing patients of the continuous dopaminergic theory and providing specific drug timings. Once daily drugs are taken more consistently than drugs with more frequent doses.
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Yaqub, Ohid. "Knowledge accumulation and vaccine innovation : lessons from polio and HIV/AIDS." Thesis, University of Sussex, 2010. http://sro.sussex.ac.uk/id/eprint/2382/.
Full textAbstract:
This thesis contrasts vaccine innovation efforts in the cases of poliomyelitis and HIV/AIDS. It addresses the question of why some fields of human endeavour can be seen to yield positive change more quickly than others. The thesis develops a perspective that views innovation as a cumulative learning process. It employs the notion of a ‘testing regime' to draw attention to the role of testing in driving this carefully managed learning process during the development of vaccines. Repeated testing, under conditions that are varied using instruments and skill, generates knowledge that is reliable and robust for technological purposes. Governance is needed to co-ordinate this process of testing to ensure the resulting knowledge growth is shared and cumulative. This lens is used to explore the creation of intermediate conditions, the development of instrumentalities, and the role of governance in vaccine innovation processes. The thesis uses the notion of ‘social visions' to explore how attention directed to poliomyelitis contrasted with neglect and apathy afforded to AIDS in its early manifestations. Shared, rather than competing, visions are found to play a significant role in setting the vaccine innovation process in motion. However, the thesis finds that key pathogenic features of the virus and certain ethical and safety stances make learning and the accumulation of technological knowledge inherently difficult. Importantly, the thesis finds policy measures can mitigate or exacerbate these learning challenges considerably. Whilst greater market support and increased research funding tend to be positive contributions to vaccine development, this research shows they are only part of what is needed to take ideas through to innovation. The empirical evidence gathered in this thesis, when viewed through the testing regime lens, suggests that science and innovation are distinct activities but their inter-relationships can be enhanced with the development of an infrastructure focussed on nurturing skills, fostering the use of new techniques, encouraging the development of new instruments, and implementing governance measures to co-ordinate testing efforts and resources.
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Ispasanie, Emma Helena Berta. "Immune responses to prototype GMMA vaccine against Neisseria meningitidis in Africa." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5855/.
Full textAbstract:
Neisseria meningitides is a major cause of meningitis epidemics in sub-Saharan Africa. A promising broadly-protective vaccine approach is outer membrane particle-based vaccine comprising GMMA (Generalised Modules for Membrane Antigens). To better understand vaccine potential and immune responses induced by GMMA, we (i) typed outer membrane vaccine antigens fHbp, NadA, NHBA and PorA in African serogroup A, W and X isolates, (ii) produced GMMA from recombinant strains expressing fHbp variant 1 or NadA-3, and (iii) generated and characterised monoclonal antibodies (mAb) against GMMA. Characterisation of 94 isolates showed limited variability of fHbp, NadA and PorA over time and geographical region. Mice immunised with GMMA developed cross-reactive bactericidal antibody responses against diverse serogroup A, W and X isolates that targeted fHbp, NadA and other unidentified antigens. We obtained 33 hybridoma clones producing GMMA-binding mAbs. Four mAbs of immunoglobulin subclasses IgG1, IgG2a/b and IgG3 bound NadA and four IgG1 mAbs bound fHbp. The other 25 mAbs recognised seven other antigens. In bactericidal assays all anti-NadA mAbs killed the vaccine serogroup A strain. Five mAbs against unknown antigens also showed bactericidal activity against another A isolate. Conclusively, the results provide support for developing a GMMA-based vaccine with broad coverage against meningococcal meningitis for Africa.
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Noordali, Hannah. "Investigating novel drug treatments for heart failure." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8503/.
Full textAbstract:
Perhexiline is a metabolic modulator considered to be an alternative pharmacotherapeutic agent in heart failure (HF), a debilitating condition characterised by severe metabolic disturbances (i.e. impaired substrate utilisation and energy production) in which morbidity and mortality are high. However, perhexiline therapy requires regular plasma monitoring, which is clinically unattractive. Moreover, its exact cardioprotective mechanism(s) remains unknown. The work in this thesis aimed to investigate the protective effects and underlying molecular mechanism(s) of perhexiline ex vivo, in Langendorff-perfused mouse hearts and in vivo, in the abdominal aortic constriction model of HF, and to determine whether the effects could be replicated by the novel perhexiline derivative, fluoroperhexiline-1 (FPER-1), which has better pharmacokinetics. Ex vivo, 2 μM perhexiline or 10 μM FPER-1 perfusion increased cardiac contractility and relaxation pre-ischaemia and improved post-ischaemic haemodynamics and hypercontracture magnitude. This involved enhancing the contractility-relaxation pathway (phospholamban (PLB) deactivation) pre-ischaemia and improving glucose metabolism (pyruvate dehydrogenase (PDH) activation and glycogen synthase kinase 3αβ (GSK3αβ) deactivation) during ischaemia. In vivo, 4-week gavage with 70 mg/kg perhexiline or FPER-1 attenuated hypertrophy and cardiac remodelling at end-diastole whilst decreasing the expression of uncoupling protein 3 (UCP3), a redox-sensitive protein. Additionally, perhexiline alone improved systolic function (i.e. improved left ventricular ejection fraction and fractional shortening) in parallel with PLB deactivation. Taken together these results provide novel evidence that perhexiline protects the heart against ischaemic injury and delays progression from hypertrophy to failure by metabolic and non-metabolic (PLB) mechanisms, most of which were replicated by FPER-1.
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Shilbayeh, Sirin. "Systematic overview of clinical trials of antiarrhythmic drugs." Thesis, University of Nottingham, 1998. http://eprints.nottingham.ac.uk/30616/.
Full textAbstract:
BACKGROUND Arrhythmia is a cardiovascular disorder which can lead to several complications. Over the past decade the introduction of many new drugs has raised concerns about their questionable benefits and cost-effectiveness. Classification of antiarrhythmic drugs has not been fully resolved. Although numerous clinical trials have been conducted, the value of antiarrhythmic drugs in many indications remains controversial. Two meta-analyses of clinical trials addressing the indication of quinidine (Class I) for maintenance of sinus rhythm after cardioversion have suggested high efficacy rates but increased mortality relative to placebo. Several overviews which were conducted to evaluate the impact of antiarrhythmic therapy on improving survival post acute myocardial infarction, have defined a turning point in the management strategy from Class I to Class III drugs, particularly amiodarone and sotalol, due to the unfavourable mortality outcome with the former Class. MAJOR AIMS This thesis was conducted with three major aims: 1) To assess both qualitatively and quantitatively the benefits and risks associated with flecainide (Class Ic), amiodarone (Class III), and sotalol (Class III & II) in treatment of chronic atrial fibrillation, acute medical or surgical supraventricular arrhythmias, and life-threatening ventricular arrhythmias developing post acute myocardial infarction; 2) To produce an overall summary estimate of effectiveness and probabilities of incidence of adverse effects, which can be useful for subsequent incorporation in cost-effectiveness analysis; 3) To validate the usefulness of various therapeutic outcomes implemented by general treatment guidelines. OVERVIEW OF THESIS A meta-analysis was carried out to compare the efficacy and safety of three antiarrhythmic agents (flecainide, sotalol, and amiodarone) in maintaining sinus rhythm after cardioversion of chronic atrial fibrillation. 42 of 119 clinical trials retrieved satisfied the predefined inclusion criteria. Data from 17 amiodarone trials (5 randomised, and 12 uncontrolled), 8 sotalol trials (6 randomised, and 2 nonrandomised), and 19 flecainide trials (8 randomised, 4 nonrandomised controlled, and 6 uncontrolled) were pooled separately after testing for homogeneity of treatment effect across the trials. Although the pooled rate difference in proportion of patients remaining in sinus rhythm between amiodarone and placebo (2 trials) was statistically nonsignificant (RD3mon = 16.1 %, 95% CI = -29.7 to 61.7, P>0.05), the pooled effect compared to Class IA drugs (3 trials) demonstrated significant differences at all time intervals (RDs were 20.5%, 31 %, and 28.8% at 3, 6, and 12 months respectively). Aggregating sotalol efficacy data in randomised or nonrandomised controlled trials has yielded highly significant effect in favour of sotalol as compared to placebo and equal effect as compared to Class IA and Class IC at all time points. Furthermore, comparison of flecainide to placebo or Class IA has revealed a highly superior effect in favour of flecainide. The calculated summary statistics (ORpeto, ORMH, RD, and RR) for the incidence of mortality and pro arrhythmia in the full-exposure group in amiodarone and sotalol trials were not significant, affirming the safety of those two drugs. In flecainide placebo-controlled trials, the ORMH for mortality and proarrhythmia were 1.8 (95% CI, 1.2-2.7, P=0.002), and (95% CI, 4.23-10.6, P<0.00l) respectively, thus indicating low benefit-risk ratio for flecainide as compared to amiodarone. The validity of this meta-analysis was examined by assessment of publication bias using funnel-plots. A funnel-plot of the amiodarone clinical trials displayed the shape of an 'inverted funnel', thus suggesting an evidence of low retrieval bias. However, due to the small sample size identified (18 trials only), a firm conclusion with regard to absence of publication bias could not be drawn. Evolving strategies for management of newly occurring supraventricular arrhythmias were reviewed. A meta-analysis was undertaken to determine the most effective agent for prompt cardioversion to sinus rhythm. Flecainide efficacy relative to placebo was confirmed by pooling data from 5 placebo-controlled trials (OR3hrs, 7.2; 95% CI, 4.7 to 11.1; Z=8.9; and OR8hrs, 5.5; 95% CI, 3.6 to 8.4; Z=7.85). However, pooling the data from three amiodarone, placebo-controlled trials at 3 and 8 hour-intervals demonstrated a nonsignificant effect (OR3hrs, 1.3; 95% CI, 0.7-2.4; Z=0.85; and OR8hrs, 1.03; 95% CI, 0.6-1.8, Z=0.12). All individual odds ratios for intravenous sotalol compared to placebo were highly significant with pooled OR at 1 hour of 8.8 (95% CI, 4.7-16.5; Z=6.8). The effect sizes of the three agents on mean ventricular response rate was estimated for both converted and unconverted patients. Whilst the effect size of flecainide versus placebo was not statistically significant at any time point, those of sotalol and amiodarone were statistically and clinically meaningful for both converted and unconverted patients. It is suggested that for acute cardioversion, intravenous flecainide or sotalol should be initially implemented. Intravenous amiodarone can be subsequently introduced for controlling the ventricular rate in persistent unconverted patients. Recent meta-analyses of randomised controlled trials of secondary prevention of myocardial infarction by antiarrhythmic agents have questioned the validity of using arrhythmia suppression as a substitutive end point for mortality. A meta-analysis examining the effect of sotalol and amiodarone for prevention of death post acute myocardial infarction was undertaken. In addition to single point estimates of pooled odds ratios of total mortality and sudden death, a meta-analysis of survival data which included censored end points was employed. An attempt was made to reconstruct the life tables in individual trials of amiodarone. The Kaplan-Meier percentages were recalculated and pooled at specific time points to reproduce the final meta-analytic survival curves of total mortality and sudden death. The meta-analysis confirmed the clinical efficacy of amiodarone for prolonging the survival in patients with congestive heart failure or myocardial infarction. The nonparametric log-rank odds ratio method was applied to raw actuarial data deduced from published Kaplan-Meier graphs as well as data generated by curve fitting. Pooling each set of data separately has yielded highly significant log-rank ORs for total mortality in the first set of four trials with censoring (log-rank OR at 102 months, 0.598; 95% CI, 0.43 to 0.83; Z = -3). However, log-rank ORs from data generated by curve fitting of data from a further three trials, were nonsignificant up to 48 months (log-rank OR, 0.87; 95% CI, 0.72 to 1.06, Z = -1.4). Merging of the two data sets has suggested strong evidence of efficacy for improving survival in terms of both total mortality and sudden death.
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Schoeb, Mezzanotte Veronika. ""What do you expect from physiotherapy?" : a conversation analytic approach to goal setting in physiotherapy." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14210/.
Full textAbstract:
Professional practice guidelines direct health care professionals to include patients in the decision-making process and to establish collaboration for therapeutic goal setting. Currently, little is known about the interaction between patients and professionals during this process. The aim of this study is to shed light on goal setting practices in physiotherapy. Twenty-eight consenting patients seeking physiotherapy for their musculoskeletal problems and their therapists were videotaped during three consecutive sessions. Sequences related to goal setting were selected, and Conversation Analysis was chosen to analyse patient-therapist interactions. The data comprise fifteen episodes in which therapists enquire explicitly about goals. Findings show that two assumptions underlie these enquiries: a) that patients have a goal in mind, and b) that they are able to articulate it. My data indicate that this is not straightforwardly the case in practice. Patients orient in their responses to epistemic dimensions related to issues of whether they have access to this knowledge, and whether they treat themselves as entitled to know about goals. When patients respond to therapists’ enquiries, they use a variety of interactional resources to convey their epistemic orientation. I further found that therapists use different strategies for following-up patients’ responses: these have different implications for patients’ continued talk. My analysis also shows that a goal can only be treated as acceptable by therapists when it is amenable to improvement by physiotherapy. My study indicates that the process of goal setting is not as straightforward as policy documents suggest. In actual practice it requires addressing and managing underlying assumptions and epistemic dimensions. A better comprehension of the interaction between physiotherapists and patients will contribute to better understand the limitations of current goal setting theory, and how and why current policies on goal setting may not have the desired effect.
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Mazlan-Kepli, Wardati. "Antiplatelet therapy and clinical outcomes in cardiovascular diseases." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7831/.
Full textAbstract:
Cardiovascular diseases (CVD) is a leading cause of death in the world. Despite effective treatment regimens for ischaemic heart disease (IHD) and ischaemic stroke, mortality and recurrence rates remain high. Antiplatelet therapy is on effective treatment and reduces the risk of recurrent heart attack and stroke. Nevertheless, there are patients who stopped or interrupted their antiplatelet therapy for certain reasons or some patients may be resistant or poor responders to antiplatelet therapy. Furthermore, there is evidence of rebound effect in platelet activity after antiplatelet cessation and this may associate with increased risk of cardiovascular event. This thesis is divided into five main chapters (chapters 3 to 7) which attempt to provide data to help resolve the uncertainty. Chapter 1 highlights the background of cardiovascular diseases and the global burden of cardiovascular and cerebrovascular diseases. The metabolism of platelets, antiplatelet therapy and current antiplatelet therapy guidelines are described, followed by discussion of the risk of cardiovascular event and changes in antiplatelet therapy. Chapter 2 describes the data source from Virtual International Stroke Trial Archive (VISTA) and National Health Service Greater Glasgow and Clyde (NHSGGC) Safe Haven, followed by definition of outcome measures. In chapter 3, Virtual International Stroke Trial Archive (VISTA) data was examined to test whether continue with the same antiplatelet therapy or changing to a new antiplatelet regimen reduces the risk of subsequent events in patients who experience a stroke whilst taking antiplatelet therapy. The findings indicate that subjects who switch to a new antiplatelet regimen after stroke did not have a lower early recurrence rate than subjects who continued with the same antiplatelet therapy. Observations on bleeding complications were similar in both groups. However, changing antiplatelet regimen after stroke was associated with more favourable functional outcome across a full scale modified Rankin Scale (mRS) at 90 days. In chapter 4, association between early or later initiation of antiplatelet with a recurrent ischaemic stroke and bleeding complications was assessed using VISTA data. The findings indicate that there was no association between a recurrent ischaemic stroke and timing of initiation of antiplatelet drug after stroke. However, early initiation was associated with increased risk of bleeding. In terms of functional outcomes, this study demonstrated that the mid-time and late initiation of antiplatelet therapy after acute stroke are associated with better functional outcomes compared with early initiation. In chapter 5, a nested case-control study was performed to explore the rate of antiplatelet cessation and interruption in a sample of patients with recent ischaemic stroke and to assess the risk of cardiovascular events associated with cessation and interruption of antiplatelet. It was found that there was no increased risk of cardiovascular event among patients who had early cessation or interrupted/stopped antiplatelet therapy within 90 days following acute ischaemic stroke. In chapter 6, the incidence and predictors of cardiovascular events after DAPT cessation were evaluated. The incidence of cardiovascular event while taking DAPT and following discontinuation of DAPT was 15.7% and 16.7% respectively. This study found that increasing age was associated with an increased risk of cardiovascular event, whereas, revascularization-treated patients and longer duration of DAPT, were each associated with a decreased risk. The duration of DAPT six months and less was associated a significantly higher risk for cardiovascular event. In chapter 7, an untargeted metabolomics analysis was performed while on DAPT (aspirin plus ticagrelor) and once they stopped ticagrelor to identify metabolite changes associated with cardiovascular events after stopping DAPT. Ten ACS patients were recruited in this study and data were analysed for seven patients. Three hundred eleven putative metabolites were identified. This study found 16 putative metabolites significantly altered following ticagrelor cessation. Of these, seven metabolites were from lipid pathway and down-regulated some up to 3-fold. On the other hand, adenosine, from nucleotide metabolism was upregulated up to 2.6-fold. It concluded that there are changes in numerous pathways following DAPT discontinuation and whether these changes differ in patients who have cardiovascular event after stopping DAPT warrant further investigation. In chapter 8, a summary of the findings of this thesis are presented as well as the future directions of research in this area.
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Mahdi, Mohammed Hamzah. "Development of gellan gum fluid gel as modified release drug delivery systems." Thesis, University of Huddersfield, 2016. http://eprints.hud.ac.uk/id/eprint/30293/.
Full textAbstract:
Gelation of polysaccharides under shear conditions results in the formation of a weak gel which is able to resist elastic mechanical deformation at small strains but will flow if subjected to higher strains. The resulting material, described in the literature as a fluid gel or a sheared gel, consists of gelled microparticles which can be formulated to collectively act in bulk, as pourable viscoelastic fluids whilst retaining true gel characteristics at the micro/nano level. The tuneable behaviour of these fluid gel systems makes them potentially useful in pharmaceutical applications. Fluid gels prepared from gellan gum are particularly attractive, due to its sensitivity to physiological fluids, unique rheological and physical properties, and current regulatory approval for use as a food additive and pharmaceutical excipient. Therefore, the aim of the present study was to investigate gellan gum fluid gels as a new modified release drug delivery platform. The formation and production of fluid gels using low acyl (LA) gellan, high acyl (HA) gellan and LA HA gellan blends was investigated and applied in three different dosage forms; a modified release oral liquid, a mucoadhesive nasal spray and a topical formulation. A modified release oral liquid was designed using a fluid gel prepared from LA gellan gum. It was demonstrated that 0.75 % w/w LA gellan gum fluid gel, containing ibuprofen as the drug, could be formulated to have a similar viscosity profile as a marketed oral ibuprofen liquid. Furthermore, due to the acid insolubility of gels prepared from LA gellan, no ibuprofen was released in stimulated gastric fluid. Subsequent release at pH 7.4 however, was affected by the duration of exposure and strength of the acidic pH used and a linear relationship between onset of release and the preceding duration of acid exposure was observed. Delayed release was a result of increasing gel stiffness, a consequence of the acidity of the initial release media and exposure time. A much faster release rate was measured when exposure time in acid was 10 min compared with 60 min. This study highlights the potential to design fluid gels that are tuned to have a specified stiffness at a particular pH and exposure time allowing the intelligent design oral liquids with specific modified release behaviour. The second part of this study was to prepare mucoadhesive nasal drug delivery systems to enhance the retention of the nasal spray dosage form in the nasal cavity. Several groups have investigated using LA gellan solution as a drug delivery vehicle but only limited research however, has been performed on HA gellan for this purpose, despite its properties being more conducive to mucoadhesion. HA gellan (even with low concentration 0.25 % w/w) produces highly elastic gels below 60 °C which make it difficult to spray using a mechanical spray device. To address this problem, fluid gels were prepared as these systems can behave as sprayable viscoelastic fluids. In this study the rheological behaviour was investigated and the mucoadhesion behaviour of fluid gels prepared from the two different types of gellan (HA and LA) and fluid gels prepared from a blend of LA HA gellan. The results demonstrated that by preparing fluid gels from a blend of LA HA gellan, the rheological properties were sufficient to spray through a standard nasal spray device. Moreover, the fluid gels significantly enhanced both HA and LA gellan mucoadhesion properties. In the final part of this thesis the topical application of gellan fluid gels was explored. A range of gellan fluid gel formulations were prepared containing diclofenac sodium for topical application. The rheological results showed that it was possible to produce a topical formulation with a viscosity and the mechanical strength similar to that of the commercially available Voltaren® gel using 1 % w/w of a 50:50 LA HA gellan blend. The permeation results highlighted that the penetration of diclofenac through procaine tissue is significantly increased by increasing gellan concentration and decreasing sodium ion concentration in the formulation.
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Velagapudi, Ravikanth. "Modulation of multiple neuroinflammatory signalling pathways by the dietary glycosidic flavonoid tiliroside." Thesis, University of Huddersfield, 2016. http://eprints.hud.ac.uk/id/eprint/31501/.
Full textAbstract:
Hyperactivated microglia plays a key role in regulating neuroinflammatory responses which propagate damage to neurons. In recent years, substantial attention has been paid in identifying new strategies to abrogate neuroinflammation. Tiliroside, a dietary glycosidic flavonoid found in several medicinal and dietary plants is known to possess anti-inflammatory and antioxidant activities. This study is aimed at investigating the molecular mechanisms involved in the inhibition of neuroinflammation by the tiliroside. Neuroinflammation inhibitory effects of tiliroside (2-6 μM) were investigated in BV2 microglia stimulated with a combination of LPS (100 ng/ml) and IFN (5 ng/ml). Results show that tiliroside significantly reduced the production of pro-inflammatory cytokines IL-6, TNFα, IL-1β while increasing the production of anti-inflammatory cytokine IL-10 in LPS/IFN-stimulated BV2 microglia. The compound reduced NO production in LPS/IFN-stimulated BV2 cells through inhibition of iNOS protein expression. Tiliroside also suppressed COX-2 protein expression and inhibited PGE2 production in activated microglia. Western blotting and functional experiments revealed that inhibition of neuroinflammation by tiliroside was shown to be mediated through inhibition of NF-B and p38 MAPK signalling pathways. Also, the compound activated SIRT1 and inhibited the expression of acetylated-NF-B-p65 in LPS/IFN-activated BV2 microglia. Further experiments revealed that inhibition of neuroinflammation by tiliroside is not dependent on SIRT1. Tiliroside increased the levels of Nrf2, HO-1 and NQO1 antioxidant proteins, indicating an activation of the Nrf2 protective mechanisms in the microglia. Furthermore, transfection of BV2 cells with Nrf2 siRNA resulted in the loss of anti-inflammatory activities of tiliroside. Results of neurotoxicity experiments showed that neuroinflammation-induced neurodegeneration, DNA fragmentation, ROS generation and calcium accumulation were significantly reduced in HT22 neurons when exposed to conditioned medium from BV2 microglia that were pre-treated with tiliroside prior to stimulation with LPS/IFN. Results from this study suggest that tiliroside inhibits neuroinflammation in LPS/IFN-activated BV2 microglia by targeting NF-B and p38 MAPK signalling pathways. Furthermore, the compound activated Nrf2 antioxidant mechanisms in the microglia, which appears to contribute to its anti-inflammatory activity. The study also established that tiliroside protects HT22 neurons from neuroinflammation-induced toxicity.