Thesis (M.S.)--Ball State University, 2009. / Title from PDF t.p. (viewed on Nov. 30, 2009). Includes bibliographical references (p. 74-80).

M. Tech. Pharmaceutical Sciences Tshwane University of Technology 2013. / Aims of the present study was to evaluate the inhibitory activities of essential oils against Fusarium isolates and their corresponding biofilms. In this study, the chemical compositions of the oils were established using gas chromatography with both mass spectrometric and flame ionization detection, for identification and quantification, respectively.

M. Tech. Pharmaceutical Sciences. / Investigates the potential of A. ferox and A. vera gel and whole leaf extract materials alone or in combination with Carbopol® 971P NF and HPMC as excipients in a multi-unit controlled release matrix type system.

M. Tech. Pharmaceutical Sciences. / Aims to design, evaluate and optimize an extended release matrix tablet of Nicotinic acid using natural polymers to match the in-vitro dissolution profile of Niaspan.

Innovation is not always enough. In the beginning of the 2000s established pharmaceutical firms had developed several drugs, yet these new products were far too few. Patents of many blockbuster drugs were to soon expire and substantial profit would then be lost. A potential solution emerged: implementing new biomarker technologies in drug development. Biomarkers are required for knowledge creation about the drug effect on underlying causes of a disease. The problem is this: although academia, industry, and policy makers have deemed biomarkers as necessary for successful drug development, pharmaceutical firms have not used them in actual drug development projects.  Since the 1990s, established pharmaceutical firms have invested financially and restructured organizationally in order to implement biomarkers. Still, cases show that more than 50% of project termination in Clinical Phase 2 (the bottle neck of drug development) can be attributed to the lack of implementing biomarkers.   Challenges of established firms transforming in the face of technology change is a commonly studied phenomenon within innovation management literature. Several explanations have attempted to determine why established firms fail in following technology change. However, most of this literature has been based upon an empirical context where technology change is conceptualized as an innovation of the dominant product design in the industry. Consequently, the challenge is to develop or adapt a discontinuous product innovation. Conversely, implementing biomarkers is a case of technology change that impacts R&amp;D. Since drugs lose their value when the patent protection expires, the established pharmaceutical firms need to continuously develop new block buster drugs – not just one product. More research is needed to fill this gap in the literature in order to develop an understanding of the established firm challenge in implementing biomarkers. This thesis builds upon a longitudinal case study of AstraZeneca. Using multiple data sources, the findings show that the dominant architecture of the drug development process during the 2000s impeded the implementation of biomarkers. AstraZeneca required an “architectural process innovation” in order to complete this implementation. The company’s process-based management structures distorted it from recognizing the need for process change. This thesis has three contributions: First, it describes the process change and the firm’s managerial challenges associated with biomarker implementation; Second, it contributes to the literature on the established firm challenge by developing an understanding of the phenomenon of architectural process innovation; Third, it develops a process-based framework for studying technology change that affects R&amp;D. / <p>QC 20151106</p>

The problem of finding targeted medicine is a central problem in chemotherapy. From this point of view the ubiquitin-proteasome system is a highly promising object in the pharmaceutical approach. Proteasome plays a critical role in cellular protein degradation, cell cycle and apoptosis regulation. Proteasome inhibitors are substances blocking the actions of proteasome. Cancer cells are more sensitive to inhibition of the ubiquitin-proteasome system than normal cells. Therefore proteasome inhibitors have the potential to be successfully used in the cancer treatment. The study aimed to test various substances to identify possible proteasome inhibitors with the IncuCyteTM FLR image system and fluorometric microculture cytotoxicity assay. Using the IncuCyte FLR method allows for detecting changes in the molecular processes of living cells. To make proteasome inhibition visible the model cell line MelJuSoUbG76V-YFP is used which helps to detect alterations in proteasome activity by means of the yellow fluorescent protein enrichment in cells as a response to proteasome inhibition. Fluorometric microculture cytotoxicity assay is a method for the determination of cytotoxicity in human tumor cells. The study showed that substance #25 possessed a proteasome inhibitory capacity in a dose-dependent manner as demonstrated with the IncuCyte FLR image system. According to the fluorometric microculture cytotoxicity assay, substance #1 was the most stable and toxic. Substances #2 and #185 had selective toxicity against cancer cells and lower effects against normal cells. Combining IncuCyte FLR and fluorometric microculture cytotoxicity assay allows finding substances which act as proteasome inhibitors with high toxic effect.

In order to market and sell a new pharmaceutical drug in Canada, the Minister of Health requires the initial applicant to submit clinical test results demonstrating that the drug is safe and effective for human use. Subsequent applicants, who typically lack the resources to conduct expensive clinical trials, must refer to and rely upon the initial applicant's data in their applications to market a generic version of the drug. / On June 17, 2006, the federal government of Canada published a proposed data protection regulation, which would provide an initial applicant with eight years of protection for clinical test results submitted in a new drug submission. This protection would lead to an eight year period of market exclusivity for the drug associated with the clinical test data, regardless of whether that drug was protected by a Canadian patent. / In this thesis, the author first describes what data protection is on a practical level, and distinguishes data protection from other forms of intellectual property rights. Next, the author discusses how various jurisdictions choose to protect clinical test data submitted to their health authorities. Canada's international obligations pursuant to the NAFTA and the TRIPS Agreement are also examined. In this regard, the author argues that Canada is under no obligation to provide initial applicants with eight years of data protection. Furthermore, the author argues that exclusive time-limited property rights in clinical test data are difficult to justify from a theoretical perspective. Finally, the author prescribes certain legislative changes to Canada's proposed data protection regulation.

Plasmodium falciparum is a protozoan parasite responsible for the most severe form of human malaria, with infection often resulting in death. Efforts to control malaria have been hindered by an increased spread of parasite resistance to previously effective antimalarial drugs, leading to an intensified search for novel antimalarial drug targets. A group of proteins suggested as potentially effective targets are the integral membrane transport proteins, since they play key roles in Plasmodium parasite growth and replication. One such membrane protein recently characterised was the P. falciparum copper efflux transporter. Treatment of cultured P. falciparum parasites with the intracellular copper chelator neocuproine inhibited parasite growth, suggesting that additional mechanisms for malaria parasite copper homoeostasis are likely to be present. Copper is an essential trace element involved in enzymatic processes requiring redox-chemistry. In higher eukaryotes copper is transported across the plasma membrane via the copper transport protein, Ctr1, and distributed intracellularly by copper metallochaperones. The mechanisms for copper acquisition and distribution in the Plasmodium parasite are, however, yet to be characterised. An in silico Basic Local Alignment Search Tool for protein (BLASTp) screen of the Plasmodium database (www.plasmodb.org) identified sequences corresponding to a putative copper transporter, and associated copper metallochaperones, in eight species of the Plasmodium parasite. Each of the Plasmodium copper transport protein sequences was found to contain features common to the well characterised copper transporters. These features included predicted copper-binding motifs in the protein's amino terminus, three membrane spanning domains and the characteristic MxxxM and GxxxG motifs located in the second and third transmembrane domains, respectively. Affinity purified anti-peptide antibodies, generated against an immunogenic peptide (CSDKQSGDDECKPILD) in the amino terminus of a putative malaria parasite copper transporter (PY00413), detected the target protein in murine malaria parasites in association with a parasite membrane. The open reading frames corresponding to the amino terminal domains of one P. berghei [PBANKA_130290 (447 bp)] and two P. falciparum [PF14_0211 (132 bp) and PF14_0369 (282 bp)] putative copper transport proteins were PCR amplified, ligated into pGEM®-T and then expressed as recombinant fusion proteins with maltose binding protein (MBP). The resulting sizes for the recombinant proteins were 61kDa for MBP-PbCtrNt, 48kDa for MBP-PfCtr211Ntᵀᴰ and 55kDa for MBP-PfCtr369Ntᵀᴰ, with each protein being recognised by a corresponding anti-peptide antibody. All three recombinant proteins bound copper in vitro and in vivo, with each having a binding preference for the reduced cuprous ion. This preference has been similarly established for the characterised copper transporters. Although the results supported the expression and copper binding ability of a Plasmodium parasite copper transport protein, the directional transport of copper, by this protein, requires experimental confirmation as does its specific location. The identification of a P. falciparum copper transporter, and other copper dependent proteins, implies a parasite metabolic requirement for copper. Mammalian and yeast cells require a Cox17 metallochaperone for copper delivery to cytochrome-c oxidase. Identification of P. falciparum orthologs for Cox17 (PF10_0252) and a number of cytochrome-c oxidase subunits (PF13_0327; PF14_0288; mal_mito_1; mal_mito_2; PFI1365w; PFI1375w), suggests the existence of similar parasite mechanisms for copper delivery. Analysis of the Plasmodium Cox17-like sequences identified essential amino acids conserved in the well characterised yeast and mammalian Cox17. This included the identification of six cysteine residues essential for Cox17 function. A homology model of P. falciparum Cox17, with human Cox17 as the template [PDB ID: 2RN9 (apoCox17); 2RN8 (Cu⁺-Cox17)], suggested that Plasmodium Cox17 orthologs would adopt a similar structural conformation. The open reading frames for full-length P. yoelii [PY03823 (192 bp)] and P. falciparum [PF10_0252 (195 bp)] Cox17 were PCR amplified, ligated into pGEM®-T and then expressed as recombinant fusion proteins with either a His₆-tag or glutathione S-transferase (GST)-tag, respectively. The resulting sizes for the recombinant proteins were 11.6kDa for His₆-PyCox17 and 33.5kDa for GST-PfCox17, with each protein being recognised by a corresponding anti-peptide antibody. Both recombinant Cox17 proteins bound the cuprous ion in vitro and in vivo, similar to mammalian and yeast Cox17. This supported the likely existence of a mitochondrial copper metallochaperone pathway within the malaria parasite; however, this requires further experimental confirmation. Identification of a parasite copper transport protein, and associated metallochaperones, could provide novel targets for drug-based inhibition of parasite growth. Alternatively, the copper transporter may provide a novel mechanism for drug delivery into the Plasmodium parasite. The potential of these malaria parasite proteins being effective drug targets does, however, remain to be confirmed. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

African animal trypanosomosis is a devastating disease affecting livestock mainly found in sub-Saharan Africa. This disease is known as nagana and is transmitted by the trypanosome parasite from the tsetse fly vector to a mammalian host. There are three African trypanosomes namely Trypanosoma vivax, T. congolense and T. brucei brucei that are the causative agents responsible for this disease in African cattle. This disease is serious since it not only affects livestock but also has a negative impact on the sub-Saharan African economy. There is, therefore, a great demand for better control methods of the disease and suitable diagnostic methods. Current control measures such as the use of trypanocidal drugs, tsetse fly eradication methods and trypanotolerant cattle have become inadequate. The defence mechanism of the trypanosome to continuously change its surface coat by a process of antigenic variation has made it impossible to produce a suitable vaccine. Therefore, chemotherapy is still one of the key approaches for control of this wasting disease. The long existence of the current trypanocidal drugs has allowed the development of drug resistance. The development of new chemotherapeutic drugs is focused on targeting the pathogenic factors such as parasite cysteine peptidases that contribute to the disease. Vivapain is the main cysteine peptidase of T. vivax and shares high sequence identity with congopain, the main cysteine peptidase of T. congolense, which was previously shown to be a pathogenic factor contributing to trypanosomosis. Vivapain, thus, has potential as a target for chemotherapeutic drug design. Hence, the first part of this study involved the recombinant expression and enzymatic characterisation of vivapain for future production of new synthetic inhibitors for the use in new trypanocidal drugs. The catalytic domain of vivapain (Vp) was recombinantly expressed in the Pichia pastoris yeast expression system and enzymatically characterised. The main finding from this study was that Vp was only able to hydrolyse a substrate if the P2 position was occupied by either a hydrophobic Phe or Leu residue. Vp was also found to be active close to physiological pH and was inhibited by the reversible cysteine peptidases, leupeptin, antipain and chymostatin and the irreversible cysteine peptidases L-trans-epoxysuccinyl-leucylamido (4-guanidino) butane (E-64), iodoacetic acid (IAA) and iodoacetamide (IAN). A further important aspect of controlling trypanosomosis is the diagnosis of the disease. Clinical, parasitological, molecular and serological techniques have been applied and used to diagnose trypanosomosis. One of the most promising serological techniques has proven to be the enzyme-linked immunosorbent assay (ELISA), more specifically the antibody and antigen detection ELISAs. The main requirement for this technique is a readily available and reproducible antigen such as that produced by recombinant expression. While there are recombinant antigens that are available to be used to detect T. congolense, T. brucei brucei and even T. evansi infections, there are none available to detect T. vivax infections. In the second part of this study, a mutant inactive full length form of vivapain (FLVp) was expressed in a bacterial expression system for the detection of T. vivax infections. Antibodies against this antigen were produced in both chickens and mice. Both the chicken IgY and mice sera were able to detect the recombinant FLVp in western blots. The mice sera were also able to detect native vivapain in a T. vivax lysate, which is very promising for future use of the FLVp antigen and the corresponding antibodies in diagnosis of T. vivax infections in sera of infected animals. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

Staphylococcus aureus is a common and versatile opportunistic pathogen in humans. Increases in the incidence of community acquired and nosocomial infections, coupled with the emergence of antibiotic resistant strains, are causing new treatment challenges for health care professionals. S. aureus readily binds to the endothelial cell surface and utilizes host cell endocytosis to evade host cell immune responses. Inhibition of endocytosis may cause S. aureus to remain unprotected at the host cell surface, allowing host immune systems and other therapeutics more time to clear an infection. Simvastatin inhibits host cell endocytosis. We hypothesize that using simvastatin to inhibit S. aureus invasion of host cells, a high throughput, small molecule screen can be developed. The high throughput screen will evaluate the National Institutes of Health small molecule library for compounds that better inhibit endocytosis. Additionally, 2-dimensional gel electrophoresis will be performed to elucidate the pathway simvastatin alters to inhibit endocytosis. / Department of Biology