Cette thèse présentait comme objectif mettre en évidence le potentiel apport de l’immuno-PCR dans le diagnostic des maladies infectieuses à travers 3 exemples. L’application de l’iPCR dans le diagnostic précoce de la fièvre Q aiguë via la détection des IgM Phase II anti Coxiella burnetii a permis de détecter 90% des sérums prélevés dans les 2 premières semaines après l’apparition des symptômes contre 55% détectés par PCR, 38% par ELISA et 35% par l’IF la technique de référence. De plus une spécificité de 92% a été retrouvée par iPCR, 100% par PCR et l’IF et 90% par ELISA. L’application de l’iPCR à la fièvre Q aiguë constitue un exemple d’application de la technique plus globalement pour tous types d’infections aiguës. D’autre part, dans le cadre de la mise au point d’un modèle expérimental murin d’infection à Tropheryma whipplei, l’iPCR a servi à mesurer la réponse immunitaire mucosale via la détection des IgA anti T. whipplei dans les selles de souris. Les résultats obtenus ont permis de confirmer le rôle de la bactérie comme agent de gastroentérite via entre autre la détection d’IgA anti T. whipplei dans les selles lorsque des atteintes intestinales étaient provoquées. Enfin l’’utilisation de l’iPCR pour la détection de l’antigène Y. pestis dans des dents anciennes a permis de confirmer Y. pestis comme agent étiologique de la peste noire dans 5 charniers à travers la France et l’Italie. Une sensibilité de 41% a été retrouvée par iPCR contre 32% par PCR et 10% par ELISA. Nos résultats suggèrent que la détection des antigènes et la détection de l’ADN du pathogène semblent être 2 approches complémentaires permettant de confirmer le rôle de Y. pestis dans les différentes pandémies de peste et de mettre fin aux controverses suscitées par la seule utilisation des techniques de biologie moléculaire.Globalement, les résultats que nous avons obtenus au cours de cette thèse démontrent le potentiel énorme de l’iPCR comme technique de détection des anticorps et d’antigènes dans le domaine des maladies infectieuses tant au niveau de la sensibilité de détection qu’au niveau de son adaptabilité à différentes applications. / The objective of this thesis was to highlight the potential contribution of immuno-PCR in the diagnosis of infectious disease through 3 examples of infection. The iPCR was adapted for the early diagnosis of acute Q fever by the detection of IgM anti phase II Coxiella burnetii in patient’s sera. The results that we obtained show that iPCR could allow an early diagnosis of acute Q fever since 90% of early sera of patients with acute Q fever collected during the 2 first weeks after the onset of symptoms are detected against 55% by PCR, 38% by ELISA and 35% by IFA the gold standard. In addition, a specificity of 92% was found by iPCR, 90% by ELISA and 100% by PCR and IF. Application of iPCR to the diagnosis of acute Q fever is an example of application of the technique more generally for all types of acute infections. In a second time, the use of iPCR for the detection of Yersinia pestis antigen in ancient teeth allowed a confirmation of its role as the etiologic agent of plague in five mass graves across France and Italy. A sensitivity of 41% was recovered by IPCR against 32% by PCR and 10% by ELISA. Our results suggest that antigen and DNA detection of pathogen in ancient samples are 2 complementary approaches allowing the confirmation of the role of Y. pestis in different plague pandemic. Finally, as part of the development of an experimental murine infection with Tropheryma whippleii, the iPCR was used to measure the mucosal immune response via the detection of IgA anti T. whippleii in mouse stools. The results have confirmed the role of the bacterium as an agent of gastroenteritis via the detection of IgA anti T. whipleii in the stool when intestinal damages were caused.Overall, the results that we obtained during my thesis demonstrate the enormous potential of iPCR as a diagnostic tool of infectious disease by the ultrasensitive detection of antigens and antibodies.

A thesis submitted to the Faculty of Arts in fulfillment of the requirements for the Degree of Doctor Of Philosophy (Phd) in the Department of History at the University Of Zululand, 2018 / The study was undertaken to evaluate the impact of the Institute for Peace and Conflict Resolution (IPCR) on peacebuilding and conflict prevention in Nigeria from 2000 to 2014. Established by the government as it transitioned to democratic governance in 2000, IPCR was mandated to identify the root causes of violent conflict in Nigeria through research and provide possible solutions through evidence-informed policy and practice options, and promotion of peacebuilding strategies. Recurring violent conflicts had not only destroyed several lives and property and displaced millions from their homes, but had also retarded the nation’s growth and development. Drawing from extensive sources of qualitative and quantitative data, the study examined the peacebuilding evidence that had worked and did not work for IPCR, and why, through conflict analysis model, theories of change and intervention theory for organizational development. Through historical, evaluative and descriptive analysis, the study found out that the Institute had within fifteen years of its history contributed to the promotion of peace through design and implementation of relevant, effective and efficient peacebuilding programmes for communities, women, youth, media, legislators, public servants, traditional, religious leaders and civil society. These groups of beneficiaries are the study’s target population. There was a strong evidence to argue that the impact of the interventions were mostly in short-term as it had impacted on the mind and work of beneficiaries but not enough to manage the underlying factors behind the recurrence of violent conflict in Nigeria. Nigeria often relapsed into more violence as soon as it gained some respite. Therefore, to achieve its mandate in the long, coherent and sustainable terms, the study suggests that the Institute must scale up its programmes to drastically stem the tide of violence through community peacebuilding. IPCR must make itself more visible at the community level because that was where most violent conflict originated. While the study recognized the fact that, though, the prevalence and complexity of underlying drivers of conflict in Nigeria were far beyond the ambit of one agency, it recommends the Institute to deepen and broaden its partnership and networks for greater peacebuilding impact. Similarly, the government needs to prioritize peace and security by increasing funding and giving sustainable support to IPCR as a democratic institution. Though much of its intervention impact still needed to be studied and learned, the study contends that better and more expanded programmes will make peacebuilding more effective and promote Nigeria’s peace in the long-term.

Natural product drug discovery has traditionally been the corner stone of medicine having provided cures to many of today's most common diseases. In particular, antibiotics have revolutionised healthcare and extended human lifespan. However, since their introduction into the clinic, resistance to these drugs has arisen. With the number of new antibiotics being discovered in recent years declining, and fewer drugs making it past clinical trials, we have reached the point where antibiotic resistant infections have become common place and a serious threat to health and society. There is now an urgent requirement for the discovery of new antibiotics and in particular those with unexploited mode of action. This thesis details the different areas of natural product drug development from discovery through to analogue generation. In Chapter one, the history of natural products as therapeutics is explored with a particular focus on antibiotics and how resistance arises against these agents. It outlines why the discovery of new antibiotics is so important and new methods used to facilitate this search. Chapter two follows with the development of a screening platform for antibiotic induction, using the model Streptomyces; Streptomyces coleiolor M145. A variety of culture additives are explored for their ability to induce secondary metabolism production. Chapter three then details the sampling and identification of microbes from a pseudo-marine environment and their screening for their ability to produce secondary metabolites with antibiotic properties. The second half of this thesis centres on the non-ribosomal peptide echinomycin. Collaborators Aquapharm supplied the marine derived strain AQP-4895, capable of producing echinomycin. Chapter four details the establishment of AQP-4895 culturing conditions and the shift observed in production profile. Next Chapter five looks at producing echinomycin analogues through precursor directed biosynthesis. A range of halogenated quinoxaline carboxylic acids are synthesised and fed to AQP-4895, and the respective echinomycin analogues monitored by LC-MS. Chapter Six then aims to direct biosynthesis of the halogenated analogues, using mutasynthesis. Due to the lack of genetic data available surrounding the strain, an unusual approach was taken, using iPCR to create a template for homologous recombination.

8 1 ABSTRACT (EN) This thesis is focused mainly on understanding mechanisms of regulatory roles of C-terminal Src kinase (CSK) and phosphoprotein associated with glycosphingolipid- enriched microdomains (PAG) in the high-affinity IgE receptor (FcɛRI)-mediated signaling of murine mast cells. FcɛRI activation is initiated by aggregation of the receptor by complexes of multivalent antigen with IgE, followed by activation and enhanced activities of protein tyrosine kinases, phosphatases, adaptor proteins and number of other signal transduction molecules. The signaling events result in mast cell degranulation and release of variety of proinflammatory mediators, responsible for initiation of allergy and other inflammatory diseases. Understanding the function of key regulatory molecules controlling FcεRI-mediated mast cell activation, degranulation, and cytokines production could have therapeutic impact. CSK is a major negative regulator of Src family tyrosine kinases (SFKs) that play a critical role in various immunoreceptor signaling events. However, its function in mast cell activation has not been completely understood. Because of its cytoplasmic localization, CSK was assumed to be brought to the vicinity of the plasma membrane- bound SFKs via binding to membrane-bound adaptors and PAG was a major candidate....

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