Sutherlandia frutescens (SF), an indigenous medicinal plant to South Africa (SA), is traditionally used to treat a diverse range of illnesses including cancer and viral infections. The biologically active compounds of SF are polar, thus renal elimination increases susceptibility to toxicity. This study investigated the antioxidant potential, lipid peroxidation, mitochondrial membrane potential and apoptotic induction by SF on proximal and distal tubule epithelial cells. Cell viability was determined using the MTT assay. Mitochondrial membrane potential was determined using a flow cytometric JC-1 Mitoscreen assay. Cellular glutathione and apoptosis were measured using the GSH-GloTM Glutathione assay and Caspase-Glo® 3/7 assay, respectively. The IC50 values from the cell viability results for LLC-PK1 and MDBK was 15 mg/ml and 7 mg/ml, respectively. SF significantly decreased intracellular GSH in LLC-PK1 (p < 0.0001) and MDBK (p < 0.0001) cells. Lipid peroxidation increased in LLC-PK1 (p < 0.0001) and MDBK (p < 0.0001) cells. JC-1 analysis showed that SF promoted mitochondrial membrane depolarization in both LLC-PK1 and MDBK cells up to 80% (p < 0.0001). The activity of caspase 3/7 increased both LLC-PK1 (11.9-fold; p < 0.0001) and MDBK (2.2-fold; p < 0.0001) cells. SF at high concentrations plays a role in increased oxidative stress, altered mitochondrial membrane integrity and promoting apoptosis in renal tubule epithelia. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.

Ochratoxin A (OTA), a nephrotoxic mycotoxin, is a contaminant of several agricultural food products consumed by animals and humans. Apart from renal toxicity, in particular renal tumours, OTA may also result in teratogenicity, neurotoxicity and immunotoxicity. Sutherlandia frutescens, an indigenous medicinal plant, has shown significant potential in strengthening the immune system and in cancer treatment, with minimal side effects. The objective of this study was to determine the effects of OTA in male Wistar rats and ascertain if these effects may be reduced by S. frutescens. Rats were treated by intraperitoneal injection (i.p) with either a control (EtOH:dH20;30:70), S. frutescens (1.0mg/kg body weight), OTA (0.5mg/kg body weight) or a combination of OTA and S. frutescens for a period of 1 or 7 days (n=4). Genotoxicity and metabolic activity in peripheral blood mononuclear cells (PBMCs) were quantified using single cell gel electrophoresis (SCGE) and the methylthiazol tetrazolium (MTT) assay, respectively. Lymphocyte apoptosis and mitochondrial depolarisation were measured by flow cytometry. Fluorescence microscopy was utilised to determine renal tissue apoptosis (Hoechst staining) and OTA localisation using immunohistochemistry (IRC). SDS-PAGE and Western blot were utilised to determine protein expression in kidney tissue and serum. Ochratoxin A significantly reduced PBMC viability (14%) after 7 days, compared with Day 1 (p<0.001). Lymphocyte mitochondrial depolarisation was 56.5% and 66.2% in the OTA-only and combination groups, respectively after 7 days (p<0.001). Ochratoxin A produced an increase in DNA damage compared to the control (p<0.01). The renal tissue displayed typical signs of apoptosis such as chromatin condensation. Ochratoxin A was immunolocalised within the glomerulus. The protein analysis showed a decreased expression in the kidney mitochondrial protein fraction. Ochratoxin A preferentially bound to serum albumin and a 120kDa protein in the OTA-only and co-treatment groups after the 1-and 7-day regimes. Protein band intensities significantly decreased after the 7-day co-treatment (p<0.01). The data highlights that OTA toxicity is mediated by mitochondrial dysfunction. Furthermore, OTA disruptions in immune function may play a role in renal damage. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, Westville, 2009.

The work described in this thesis is concerned with the design and evaluation of microsphere-based systems for drug delivery into the colon. In initial experiments, techniques were devised for the preparation of microspheres from two sustained-release acrylic polymers, Eudragits RL and RS, using emulsification-solvent evaporation techniques. For Eudragit RS microspheres containing the drug 5-aminosalicylic acid, the rate of drug release could be controlled by the type and concentration of surfactant used for preparation. Consequently, formulations could be produced which released encapsulated drug instantaneously or over many hours. The surfactants may have been altering the structure of the microsphere drug-polymer matrix. Two novel analytical techniques were employed to characterise Eudragit RS microspheres containing sulphasalazine. Fourier transform-Raman spectroscopy was successfully used as a non-destructive method for qualitative and quantitative microsphere characterisation. The technique provided good agreement with a UVspectrophotometric method in quantifying the amount of drug in microsphere samples. X-ray photoelectron spectroscopy was used to estimate the concentration of sulphasalazine at the microsphere surface for samples produced with or without the use of surfactant. Across a wide range of microsphere drug loadings, the surface drug content remained remarkably constant, but was consistently lower in the samples produced using surfactant. In a parallel programme of work, using gamma scintigraphy, the transit rate of different sizes of radiolabelled materials through the human colon was investigated to determine whether there was an optimal size to maximise colon residence. There was no clear evidence of any difference in the colon residence time of 0.2 mm particles, 5 mm tablets, or 8.4 mm tablets, under normal conditions and during accelerated transit. In healthy subjects, 50% of a dose of 0.2 mm particles resided in the ascending colon for an average of 11 hours. Finally, an in vivo biopharmaceutical evaluation of sulphapyridine-containing Eudragit RS microspheres in the human colon was undertaken. For this study, a neutron activation technique was developed for microsphere radiolabelling. Microspheres could be successfully radiolabelled by incorporation of samarium oxide followed by neutron irradiation. However, it was necessary to minimise the period of irradiation and the amount of incorporated samarium oxide, since high levels of both were found to adversely affect microsphere performance. The in vivo investigation revealed that the colonic bioavailability of sustained-release microencapsulated sulphapyridine was less than 50% of unencapsulated sulphapyridine powder. This shortfall was possibly due to an interaction of the drug with colonic bacteria or in vitro/in vivo differences in microsphere drug release characteristics.

The movement and concentration of water inside hydrophilic matrices and the bioadhesive bonds formed by them have been proposed as important factors in the bioadhesion of hydrophilic matrices (Smart et al, 1991, and Mortazavi and Smart, 1993). This thesis has developed a non-invasive magnetic resonance imaging (MRI) technique to spatially resolve the self-diffusion coefficient (SDC) and concentration profiles of water inside the bioadhesive bonds formed by dry and hydrated hydrophilic matrices. The bioadhesive interaction between mucin and adhesive may affect the network structure and diffusion retarding properties of either polymer. The mobility of solutes may be used as an indicator of such changes. This thesis has developed a fluorescence recovery after photobleaching (FRAP) technique to measure the mobility of fluorescently tagged dextrans in the mucin and adhesive polymer networks. These methods were combined with basic studies of liquid uptake kinetics and bond strength through detachment force testing to study the bioadhesive bonds formed between alginate matrices and pig gastric mucus. These studies provided evidence to suggest that the bioadhesion of dry and hydrated alginate matrices involved several underlying mechanisms. In the case of bioadhesive bonds formed by dry alginate matrices, the SDC profiles indicated that the hydration of alginate and the formation of a viscous gel layer may cause the localised dehydration of mucus directly adjacent to the alginate matrix. Furthermore, the work of adhesion (Wa) of bioadhesive bonds formed between pig gastric mucus and dry alginate matrices suggested that polymer interpenetration and secondary chemical bonding might also be involved. In the case of bonds formed by hydrated alginate matrices, similar studies indicated that the bioadhesion of hydrated alginate matrices might involve polymer interpenetration and secondary chemical bonding as well as mucus dehydration, although the latter phenomenon appeared to be dependent on the molecular weight of alginate.

Despite intensive research, cancer remains one of the major causes of worldwide morbidity. It is widely believed, however, that if currently available anti-cancer drugs could be delivered specifically to tumours then the disease would have been mastered. The delivery of prodrug converting enzymes by clostridial spores specifically to the anoxic centres of tumours is one potential delivery mechanism. This is due to the extreme selectivity of spores to germinate solely in the hypoxic regions of tumours. Once germinated, the expression of a prodrug converting enzyme converts a systemical1y administered prodrug to a highly toxic drug only in the tumour. Previous studies using Clostridium acetobutylicum and Clostridium beijerinckii as the delivery vehicle highlighted that prodrug converting enzyme expression is only found in tumours. However, no significant anti-tumour affect was observed. Two possible reasons were evolved. Firstly, expression of the prodrug converting enzyme may be low, and/or, secondly, the tumours may not be colonised sufficiently to promote an antitumour effect. Preliminary studies identified that Clostridium sporogenes NCIMB 10696 may represent a more suitable host. Higher spore titres could be prepared and, once administered, higher cell counts are found in the colonised tumours. Prodrug converting enzymes with improved kinetics over pre-existing enzymes have also been identified. Once effective gene transfer systems and expression systems had been developed, suitably high levels of several different prodrug converting enzymes, in particular nitroreductases, were obtained. Initial in vivo studies on one of the early recombinant strains identified a definite anti-tumour effect. Since those initial studies, further improvements to expression have been made. It is hoped that a more significant anti-tumour affect would result from using these improved strains. It is the ultimate aim of CDEPT to have the prodrug converting enzymes integrated into the host genome so as to negate the use of antibiotics. Towards this, studies on the use of both classical and novel integrative technologies have been investigated.

This thesis is concerned primarily with the practical implementation of Bayesian methodology within the context of the pharmaceutical industry. The implementation includes the development, where appropriate, of analytic approximations to the posterior distributions of interest and graphical methods for mapping prior assumptions to posterior inference. Two critical areas within pharmaceutical research, critical in the sense of the controversy which they have aroused, have been investigated. First, Bayesian methods for the analysis of two-treatment crossover designs which fell in to disfavour in the late 1970's and early 1980's because of the US Food and Drug Administration's published view that the two-treatment two-period design was not the design of first choice if unequivocal evidence of a treatment effect was required were developed. Each type of design considered and for which methods are developed are illustrated with examples from clinical trials which have already been reported in the medical literature. Second, a Bayesian method is developed whose purpose is to classify test compounds into one of several toxicity classes on the basis of an LD50 estimate. The method is generalised to deal with a non-standard LD50 problem related to the prediction of results from a future LD50 experiment. Both of these applications arose out of a practical consultancy session within the context of a statistics group in the chemical/pharmaceutical industry. As part of the methods required for carrying out these analyses the zeros and weights associated with some non-standard orthogonal polynomial are developed as a result of which a new asymptotic expansion of the Behrens-Fisher density is developed. Further applications of the polynomials orthogonal to t-kernels are developed including problems associated with prediction in clinical trials. A FORTRAN program which has been implemented at a laboratory level within the pharmaceutical toxicology department at CIBA-GEIGY in Switzerland is provided SAS programs for a variety of the analyses developed for the two-treatment crossover designs are provided as are SAS programs for determining the zeros and weights of a number of different classes of orthogonal polynomials.

To improve the outcomes of drug therapy, there is increasing interest in the community pharmacist providing medicines management services (MMS) (Department of Health, 2000b, 2003a). In 2001, the Department of Health funded the Community Pharmacy Medicines Management Project (CPMMP) to evaluate the introduction of a community pharmacy led MMS. This thesis set out to critically assess the views and experiences of community pharmacists and general practitioners (GPs) participating in the CPMMP; exploring how relationships and perceptions of each other could influence community pharmacists carrying out a MMS, from the viewpoint of both community pharmacists and GPs. This is a qualitative study whereby eight focus groups were conducted with thirty five community pharmacists, and semi-structured telephone interviews were carried out with twenty one GPs and twenty eight community pharmacists. Data was analysed using the broad principles of Grounded Theory (Glaser and Strauss, 1967). Almost all pharmacists and GPs stated they had a good working relationship with each other prior to the MMS commencing, although a number of attitudinal barriers were identified. These included professional hierarchy, GPs' lack of awareness of a pharmacist's training and role in health care, and concerns that commercial interests could potentially affect a community pharmacist's advice. However, these data suggested that where there was an established relationship between the two professions, the most positive feedback about the MMS was reported. These data also suggested that some GPs were not supportive for community pharmacists to undertake a MMS and were generally unwillingly for the community pharmacist to have full access to patients' medical records. There were also some concerns around boundary encroachment. The project had a limited impact on improving relationships between community pharmacists and GPs, with relationships and GPs' perceptions remaining unaltered in many instances. This piece of research has highlighted that attitudinal barriers need to be addressed in order to accomplish effective collaborative working between community pharmacists and GPs.

An analysis of judicial attitudes in the United States of America towards pharmacist responsibility has shown distinct patterns or trends. Early cases set the standards for pharmacists at a high professional level. The courts later restricted liability to technical inaccuracy in prescription processing. More recently, the judiciary is recognising the necessity to apply standards appropriate to the pharmacist’s new roles and functions. A legislative gloss to these developments has been provided in the United States of America by the enactment of legislation which seeks to recognise professional roles, enhance pharmacy practice standards and improve the outcome of drug therapy for patients, by bettering patient compliance with drug regimes. There is a current expectation, particularly on the part of the public, but also on the part of health care policy makers, that pharmacists have a responsibility to detect problems with prescribed medications, and that to fail in this responsibility is a direct threat to the public health. The new expectations of drug therapy and the parallel anticipation of the participants in drug therapy have created a new duty on the part of the pharmacist, to intervene and promote the patient’s best interests. In this thesis, it is argued that this perspective is a reasonable one. Pharmacists ought to detect and prevent problems with drug therapy. The public should be disappointed if a profession, a government-sanctioned monopoly, has the ability to improve the public health but fails to do so. In turn, courts (and a legislature) that refuse to recognise expanded responsibilities for pharmacists, and that fail to impose corresponding expanded liabilities for the failure to meet a responsibility, are perpetuating an outdated view of pharmacy practice based on an incomplete understanding of the medication use system. There are solid policy reasons for imposing a higher standard for pharmacists that includes, but goes beyond, mere technical accuracy in order processing. In turn, there are limits to what pharmacists can reasonably be expected to do, and a legal system exploring the subject of expanded pharmacist responsibility should be aware of those limits.

This study aimed to evaluate the antimicrobial efficacy of medicinal hemp plant extracts to determine the antibacterial effects of indigenous Sansevieria species and exotic Cannabis sativa phytotherapy varieties. This study also assessed whether aqueous o

<p>Leonotis leonorus and Mentha longifolia are two herbs commonly used in South Africa, mostly in oral liquid dosage forms. Several disadvantages are associated with these traditional dosage forms which can perhaps be remedied by using an appropriate oral solid dosage form, provided the actual plant material in the latter still resemble, as closely as possible, the traditionally used material and provide products of suitable pharmaceutical quality. The objectives of this study were to prepare and evaluate the pharmaceutical suitability of the freeze-dried aqueous extracts of Leonotis Leonorus and Mentha Longifolia as plant raw material for the capsule dosage of these two therapies and to formulate and manufacture capsules of Leonotis Leonorus and Mentha Longifolia aqueous extract that would contain amounts of the plant materials equivalent to that found in their traditional liquid dosage forms, and have immediate release characteristics and suitability stability.</p>