LIVE CELL IMAGING OF BACTERIAL PATHOGENS BREACHING THE BARRIER OF Dissertation

LIVE CELL IMAGING OF BACTERIAL PATHOGENS BREACHING THE BARRIER OF POLARIZED EPITHELIAL CELLS - Dissertation Example 2.3 Staining with anti-cortactin and phalloidin 15 2.4 Staining with anti-ZO-1 and HOECHST 16 2.5 Extracting GFP and YFP plasmids from C.jejuni for transformations 16 2.6 Transformation of Cj 11168 wt with GFP and YFP plasmids 17 2.7 Scanning Electron Microscopy 18 2.7.1 Specimen preparation for SEM (cultured monolayers) 18 3.0 Results 19 3.1 Laser Scanning Confocal Microscopy 19 Staining with anti-ZO-1 and HOESCHT 23 Figure 11 (A-D) HOESCHT stains blue to visualise the nuclei and ZO-1 stains green to visualize the tight junctions 23 3.2 Scanning Electron Microscopy 24 3.3 Campylobacter jejuni invasion induces cytoskeletal rearrangement 28 3.4 Campylobacter jejuni invasion causes membrane ruffling 28 3.5 Analysis of wild type and DHtrA mutant C. jejuni by electron microscopy 29 3.2 Campylobacter jejuni invasion is time dependent 29 3.3 Campylobacter jejuni invasion induces cytoskeletal rearrangement 29 3.4 Campylobacter jejuni invasion causes membrane ruffling 30 3.5 Analysis of wild type and DHtrA mutant C. jejuni by electron microscopy 30 3.6 Transformation of Cj 11168 wt with GFP and YFP plasmids 30 4.0 Discussion 31 5.0 Conclusion 34 6.0 References 35 Abstract Campylobacter jejuni is a well known pathogenic bacteria commonly transmitted through contaminated food (Oyarzabal, et al., 2012). Its presence in the human intestinal gut causes disease and is one of the leading causes of gastroenteritis in human beings. By crossing the polarized epithelial barrier in the gut, it leads to increased damage to intestinal tissue although the exact mechanism by which it accomplishes this is not yet defined (Boehm, 2011). As such, the research aimed to determine this through a series of infection studies. Results of the manner in which C. jejuni breeches the barrier of polarized epithelial cells was captured through the use of high resolution field emission scanning electron microscopy (FESEM) and confocal microscopy, and the results through various strains of the pathogenic bacteria evaluated. The results of the experiments carried out in this study indicated that invasion of an epithelial cell by C. jejuni causes membrane ruffling and cytoskeletal rear rangement. It also shows that invasion by C. jejuni is time dependent and the number of pathogenic bacteria increases with time. It also shows that C. jejuni strains can also undergo transformation with the GFP and YFP in order to ensure genetic diversity and replication. 1.0 Introduction The human gastrointestinal tract has a mucosal cell layer that forms a strong barrier which protects the body from invasion by pathogenic microbes commonly residing in the intestinal lumen (Boehm et al., 2012). This class of bacteria, commonly referred to as enteric pathogenic bacteria, include Salmonella, Shigella, Heliobacter, and Campylobacter among others possess specific properties that enable them to

Critical Marketing Essay Example | Topics and Well Written Essays - 1750 words

Critical Marketing - Essay Example An examination of this and other contemporary marketing practices reveals emergent issues that deserve closer inspection in the area of marketing as a discipline. A number of these have already attracted academic investigation but the most important include the advent of the so-called relationship marketing and the increasing focus on ethics and social responsibility. There is, hence, an additional paradigm shift, which is best examined through the critical marketing perspective. Traditional Marketing The traditional marketing mix is composed of the so-called 4Ps, which was introduced by McCarthy back in the 1960s. This doctrine explains how marketing strategies, plans and approaches are designed according to four marketing elements: product, price, place (distribution channel); and, promotion (marketing communication). According to Barker and Angelopulo (2005), the fundamental task of marketing is to combine these four elements into a marketing program so that efficiency in dealing with customers is achieved. (p139) For several decades, this traditional marketing mix, dominated marketing practices because it is aligned with the core marketing principle of consumer-centrism. By 1990s, however, new marketing paradigms began to surface. The usefulness of the 4Ps became suspect as new variables emerge, calling for new marketing models. Day and Montgomery (1999) explained that â€Å"with growing reservation about the validity or the usefulness of the Four Ps concept and its lack of recognition of marketing as an innovating and adaptive force, the Four Ps now are regarded as merely handy framework.† (p3) The development stemmed from the schools and lines of thoughts that were brought about by new practices such as relationship marketing, quality management, market orientation, supply and value chain management, resource management, and networks. (Vargo and Lusch 2004, p1) Specific examples that demonstrate the changing face of marketing today is how digital t echnology revolutionizes the way people behave, interact with each other and their environment and consume products. Social networking websites are cases in point. They best represent the emergence of the so-called digital community through the Internet, which serve as some form of online version of society wherein people live their digital lifestyles: wherein they talk with each other, forge relationships, buy their needs, look for guides and directions, and so forth. These websites introduced new marketing channels. In consideration of the previously cited factors, Vargo and Lusch were able to posit how contemporary marketing has become fragmented. What happened was that the traditional conception of marketing has to be set aside in order to accommodate the requirements and challenges such as those posed by the addition of services and other intangible variables in the marketing practice as the marketplace included ideas and cultural artifacts as products. This is in addition to t he diversity in the roles of several actors and stakeholders in the development process such as institutions, ideologies, and the empowerment consumers. The dynamics of these new changes and how they call for new marketing models are best explained by a critical analysis of marketing. Critical Marketing According to French et al. (2010), critical marketing or the critical analysis