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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Screening For Genetically Modified Tomatoes &amp / Tomato Seeds And Identification Of Cry1ac And Sam-k Specific Modifications Using Gene And Construct Specific Pcr

Uckun, Esra 01 September 2007 (has links) (PDF)
This study was carried out to analyze tomato samples and tomato seeds, purchased from different food markets of Turkey randomly, for the presence of genetic modification by using PCR method as it allows more specific detection. The DNAs of collected samples were isolated according to CTAB DNA extraction protocol and also with extraction kits. Screening tests of tomatoes were done by targeting 35S promoter, NOS terminator and NptII kanamycin resistance gene with eight different primer sets. Real time PCR is used to confirm 35S and NOS positives results obtained from conventional PCR. In this study, it was observed that 14 out of 35 seed samples, and 14 out of 40 fresh tomato samples which were screened had at least one transgenic element of 35S promoter, NOS terminator and NPTII kanamycin resistance gene indicating the possible presence of genetic modifications. After screening, gene specific studies were carried out for PG, sam-k indicating F type ripening delayed tomato and the 35 1 N lines respectively and cry1Ac genes inserted in 5345-1 insect resistant tomato line. PG and sam-k specific primers were not amplified in any of the samples investigated whereas 18 out of 75 samples were cry1Ac positive and 1 out of 75 samples was sam-k positive. Positives were confirmed by sequence analysis. Additionally, construct specific primers specific to 5345-1 and 35 1 N lines were designed. PCR amplicons indicate the existence of the construct sequence. In order to verify the results, PCR products were sent to sequence analysis
202

Alcohol-induced temporal transcriptome remodeling in the prefrontal cortex in a mouse model of alcohol dependence

Lodowski, Kerrie Hall 28 April 2015 (has links)
Alcohol dependence (alcoholism) is a complex disease influenced by both environmental factors and genetic predisposition. Mouse models have been used to study many alcohol dependence-related traits and the genetics that underlie them. Two of the most commonly used mice in alcohol research are the C57BL/6J (B6) and DBA/2J (D2) inbred strains, which diverge on several alcohol-related traits including the development of acute physical dependence. Here we utilized the B6 and D2 mice as a genetic model of acute physical dependence, coupled with mRNA Differential Display (DD) and cDNA microarray analysis, to uncover the transcriptional response of the brain to an acute dose of alcohol as a function of time. About 150 genetically divergent and alcohol-responsive genes were identified between the whole brains of B6 and D2 mice using DD and were added as additional targets to the mouse microarrays. Microarray analysis of the prefrontal cortex of B6 and D2 mice revealed strain-specific, acute alcohol-responsive transcriptome remodeling manifested as temporal patterns of gene expression. Distinct expression patterns were identified for physiologically relevant alcohol-related consequences including intoxication, withdrawal and neuroadaptation. In silico characterization of the differentially expressed genes showed genotype dependent and independent transcriptional regulation and functional classification. In addition, categorization of differentially expressed genes by their cellular profiles revealed that some of the genes were known to be more highly expressed in either excitatory or inhibitory neuronal cell types. Our results indicate that the B6 and D2 prefrontal cortices have very different cellular and molecular responses to acute alcohol exposure. The specific roles that the genes identified in this study may play in mediating the divergent alcohol-related behavior between the strains warrant further study. / text
203

Knowledge tracking of organically produced and generically modified food

Van Rensburg, D. B. J. (David Benjamin Janse) January 2012 (has links)
D.Tech. Business Administration. Business School. / Focuses on the awareness and knowledge of consumers on organically produced and genetically modified food, and how their self-rated level of knowledge impacts on their attitudes, perceptions and purchasing behaviour in the field. Furthermore, it highlights changes in consumer knowledge, perceptions, attitudes and purchasing behaviour over time, indicating to the rate of acceptance of these foods. In addition, it also supplies guidelines for future marketing communication on such food.
204

How Corporate Concentration Gives Rise to the Movement of Movements: Monsanto and La Via Campesina (1990–2011)

Giacomini, Terran 15 September 2011 (has links)
As of 2011 a revolutionary ‘movement of movements’ is emerging coterminous with environmental crises and various other crises including corporate globalization. This study sheds theoretical and empirical light on the origins of the movement of movements. Employing gendered, ethnicized class analysis, this study investigates Karl Marx’s (1867) central discovery in Capital volume one, chapter 32 that corporate concentration and organization impels workers to resist and become a revolutionary class for themselves. Data is derived from investigation into the social movement La Via Campesina’s (‘the peasant way’) struggle against Monsanto Corporation in India, the European Union and Brazil during two periods of Monsanto’s concentration (1996–1998 and 2007–2011). Findings indicate that, in the process of Monsanto’s concentration, there was a leap forward in the formation and actions of the movement of movements. This study concludes that corporate concentration and global organization significantly impels the formation of the movement of movements. / Social Science and Humanities Research Council (SSHRC)
205

Lymphocyte Contributions to Local and Systemic Cardiovascular Regulation in Mouse Pregnancy

Burke, Suzanne Diana 02 September 2010 (has links)
Healthy term pregnancy requires precisely timed coordination of multiple systems, including reproductive, neuroendocrine, immune and cardiovascular. Dynamic maternal alterations occur systemically as well as locally within the reproductive tract. Systemic cardiovascular changes during gestation are relatively conserved in mammals, permitting comparison. These physiological changes are relatively acute and reversible, in contrast to the pathological changes seen during cardiovascular disease development. Gestational hypertensive disorders, such as preeclampsia, are the leading causes of maternal and fetal morbidity and mortality. The pathogenesis of preeclampsia is not fully elucidated, but perturbation of the immune system is a fundamental component. The angiogenic and vascular properties of uterine NK lymphocytes have been well studied in mice and women, but their relationships to gestational blood pressure regulation and cardiovascular adaptations have not been addressed. In non-pregnant women and mice, T cells, but not B cells, have been found to alter cardiovascular functioning. NK cells in humans also possess these capabilities, but no functional studies have been completed. The aim of this thesis was to define the role of NK and T lymphocytes in cardiovascular adaptations during mouse gestation. Using chronic radiotelemetry, histology, post-mortem and other techniques, female inbred mice of differing genotypes that lack specific lymphocyte subsets were compared before and across gestation. In normal, immune competent mice, a five-phase gestational blood pressure profile was found. This dynamic profile corresponded to stages of placental development. In mice with a compound deficit in arterial modification and lymphocytes, no gestational hypertension was observed. To elevate the maternal challenge of pregnancy, studies of pregnant, autoimmune Type 1 Diabetic mice were conducted. Impaired spiral artery remodeling, dysfunctional lymphocytes and growth-restricted fetuses were identified. From mid-gestation, diabetic pregnant mice were hypotensive and bradycardic and showed signs of pre-renal failure (proteinuria and electrolyte imbalances). In pregnant mice lacking T cells, tachycardia was observed despite otherwise normal gestational outcomes. In pregnant mice lacking T cells with impaired NK cells, blood pressure was blunted and tachycardia was observed. These findings support the conclusion that impaired spiral artery remodeling is insufficient to cause gestational hypertension in mice. The data further identify a role for T and NK cells in cardiac function during gestation. / Thesis (Ph.D, Anatomy & Cell Biology) -- Queen's University, 2010-09-01 20:56:15.648
206

Application of thermostable a-Amylase from Thermomyces lanuginosus ATCC 58157 to nutritionally enhance starch based food

Padayachee, Thiriloshani January 2006 (has links)
Thesis (D. Tech.: Biotechnology)-Dept. of Biotechnology, Durban University of Technology, 2006 xii, 274 leaves / In Sub-Saharan Africa there is an urgent need to sustain and improve the quality of its food resources. Poverty eradication features high on the agenda of a number of world health organisations, while the number of underweight children in Africa continues to increase (Pellet, 1996). Providing nutritionally enhanced foods to the poor will help towards achieving this objective. Protein-energy malnutrition has been identified as one of the most important problems facing Africa, with maize as the staple diet (Nkama et al., 1995). However, a combination of several factors limits availability and the nutritional quality of maize. During starvation, energy and protein intakes decrease by 20-30%, with most of the children in Africa having an average protein intake of only 20 g per day (Igbedioh, 1996). Energy availability also affects protein utilization because of interrelationships of protein and energy metabolism (Elwyn, 1993). The diets of inhabitants in developing regions depend mainly on cereals (maize) for both protein and dietary energy which lacks indispensable amino acids, minerals, vitamins and carbohydrates. In light of these growing concerns an attempt was made to devise a scientific strategy to combat the nutritional shortfalls of maize meal. A multidisciplinary and concerted approach was followed within this project aimed at designing an improved thermostable amylase and applying the enzyme to nutritionally enhance maize meal. It was envisaged that the manipulation of maize meal, by the application of enzyme technology will improve the nutritional status of this staple food. The consequences is that an alternate solution for the eradication of an ailing, poverty stricken and malnourished African population is achievable. It is possible that the boundaries defining the limits of life will extend to even greater extremes through the application of novel technologies.
207

Genetic Engineering of Lactobacillus casei for Surface Displaying the Green Fluorescent Protein: An Effort towards Monitoring the Survival and Fate of Probiotic Bacteria in the Gastrointestinal Tract Environment

Chan, Colin H. L. 28 February 2014 (has links)
With the introduction of antibiotics in animal feed becoming less popular, the agricultural industry has begun a shift towards the use of probiotics in animal feed. Since there is no current method to evaluate the risks of using genetically modified probiotics in animal feed. The goal of this project was to create a genetically modified model organism for risk assessment. The genetic marker for that was chosen was GFP that was to be expressed on the surface of the cell. The fluorescent properties allow for visualisation of the genetically modified bacteria and the surface expression would allow for the easy capture and recovery of the bacteria for culturing and cell counts. Genome wide screens were performed using the CW PRED algorithm to locate proteins with LPXTG motif for cell wall anchoring. 16 hypothetical proteins were detected and 6 were selected as candidates for possible surface display of GFP. Of these candidates, the novel L. casei protein LSEI_2320 was found to be expressed at the mRNA during early growth by RT PCR and at then protein level during stationary phase with western blot. This LPXTG protein was found at the surface of L. casei ATCC334 during stationary phase and late stationary phase with immunofluorescence microscopy. A genetically modified L. casei ATCC334 was constructed using the surface protein LSEI_2320 locus as a region for recombination with the pRV300 suicide plasmid. Genetic modification of the locus by the insertion of a GFP reporter region just before the predicted signal peptide site resulted in the abrogation of the expression of LSEI_2320 from the cell surface at the late stationary phase. It appears that this particular gene is not necessary to cell survival even though it is abundantly expressed on the cell surface and can be used as a location for genetic modification in L. casei ATCC334.
208

The Multiple Faces of Genetically-Modified T Cells : Potential Applications in Therapy

Hillerdal, Victoria January 2014 (has links)
In this PhD thesis the potential of T-cells as therapy for disease are explored. The applications of genetically modified T-cells for treatment of cancer and autoimmune disease; the functionality and optimal activation of T-cells are discussed. Successful treatment of cancer with T-cell receptor (TCR)-modified T-cells was first reported in 2006, and is based on recognition of a specific peptide by the TCR in the context of the MHC molecule. As antigen presentation in tumors is often defective and to avoid MHC-restriction, chimeric antigen receptors (CAR) molecules containing an antibody part for recognition of cell surface antigens and TCR and co-receptor signaling domains have been developed. Activated T-cells mount an efficient immune response resulting in the killing of the cancer cell and initiating T-cell proliferation. The rationale for using genetically modified T-cells instead of isolating tumor infiltrating lymphocytes from the tumor and expanding them (TIL therapy) is that it is often very difficult to obtain viable lymphocytes that are able to expand enough in order to use them for therapy. This thesis explores the possibility of using prostate-specific antigens to target T-cells towards prostate cancer. The prostate has many unique tissue antigens but most patients with metastatic prostate cancer have undergone prostatectomy and consequently have “prostate antigen” expression only in cancer cells. We targeted the prostate antigens TARP and PSCA with a HLA-A2 restricted TCR and a CAR respectively. In both cases the tumor-specific T-cells were able to generate potent proliferative and cytotoxic responses in vitro. The PSCA CAR-modified T-cells delayed subcutaneous tumor growth in vivo. It is evident from our in vivo experiments that the PSCA CAR T-cells were unable to completely cure the mice. Therefore, we aimed to improve the quality of the transferred T-cells and their resistance to the immunosuppressive tumor microenvironment. Stimulation with allogeneic lymphocyte-licensed DCs improved the resistance to oxidative stress and antitumor activity of the T-cells. We further investigated the potential of genetically modified regulatory T-cells (Tregs) to suppress effector cells in an antigen-specific manner. Using a strong TCR we hypothesize that the phenotype of the TCR-transduced Tregs may be affected by antigen activation of those cells. We found that the engineered Tregs produced cytokines consistent with Th1, Th2 and Treg phenotypes.
209

The international political economy of the Cartagena Protocol on biosafety

Du Plessis, Marthinus Johannes 03 1900 (has links)
Thesis (MA)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The development of the global biotechnology industry largely coincided with the development of the US biotechnology industry. This resulted in this industry's oligopolistic and centralised nature where only a few multinational chemical and pharmaceutical companies control most biotechnology processes and production of commodities emanating from these processes. The governance of biotechnology has, until recently, been dominated by state actors who have endeavoured to secure national interests, including those of large multinational corporations (MNCs) based within their boundaries. The technological ability of developed states to exploit and use unevenly distributed resources to their advantage means that an uneven relationship exists between these and poor developing countries. This has been highlighted by differences in public opinion about the role and application of biotechnology in society. While some opinions favour the use and application of biotechnology to enhance food supplies and boost production levels and trade, other opinions caution against the possible hazards that genetically manipulated organisms (GMOs) hold for the environment and human existence. The commercialisation of biotechnology has resulted in the exponential growth of genetically manipulated crops in especially the United States and countries like Argentina and Canada. These countries produce large surpluses of staple grains such as corn and soya and try to sell these to countries with food supply problems. The clash in commercial interests stemming from developed countries' insistence on the protection of intellectual property rights (IPR) on genetically manipulated (GM) seeds has caused considerable conflict with poor farmers who will not be able to sustain their livelihoods if they cannot save seeds for future harvests. This is one aspect of the problems surrounding the protection of knowledge products that is exacerbated by the scientific uncertainty pertaining to the risk involved with biotechnology. While some observers agitate for precaution with the use of GMOs, others feel that a lack of scientific proof of harm is sufficient grounds for proceeding with developments in biotechnology. Conversely, there are some that feel that biotechnology is market driven instead of human needs driven, ultimately resulting in developing countries receiving very little benefit from it. The Cartagena Protocol on biosafety was drafted to address some of the difficulties involved with the transboundary movement of GMOs. Although it holds very specific advantages for developing countries, as a regulatory framework it is limited in its scope and application. Developing countries are limited in their policy options to address their need to protect biodiversity and secure their food supply. This means that considerable challenges and constraints await these countries in utilising global governance of public goods and building their human and technological capacities. / AFRIKAANSE OPSOMMING: Die ontwikkeling van die globale biotegnologie-industrie het grootliks saamgeval met die ontwikkeling van die Verenigde State se biotegnologie-industrie. Dit het aanleiding gegee tot hierdie industrie se oligopolistiese en gesentraliseerde aard waar slegs enkele multinasionale chemiese en farmaseutiese maatskappye die meeste biotegnologie prosesse en die vervaardiging van kommoditeite uit daardie prosesse beheer. Die regering van biotegnologie was tot onlangs oorheers deur staatsakteurs wie gepoog het om nasionale belange te beskerm, insluitend die belange van multinasionale korporasies (MNK) wat vanuit hulle grondgebied funksioneer. Die tegnologiese vermoë van ontwikkelde state om oneweredig verspreide hulpbronne tot eie gewin te benut beteken dat 'n ongelyke verhouding bestaan tussen hierdie en arm ontwikkelende state. Dit word beklemtoon deur verskille in openbare mening oor die rol en aanwending van biotegnologie in die samelewing. Terwyl sekere opinies ten gunste van die aanwending van biotegnologie vir die verbetering van voedselbronne en produksievlakke en handel is, dui ander opinies op die moontlike gevare wat geneties gemanipuleerde organismes (GMOs) vir die omgewing en menslike voortbestaan inhou. Die kommersialisering van biotegnologie het gelei tot die eksponensiële groei van geneties gemanipuleerde gewasse in veral die Verenigde State en state soos Argentinië en Kanada. Hierdie state produseer groot hoeveelhede stapelgrane soos mielies en soja en poog om dit te verkoop aan state met voedselvoorsieningsprobleme. Die botsing in kommersiële belange wat spruit uit ontwikkelde state se aandrang op die beskerming van intellektuele eiendomsreg op geneties gemanipuleerde saad veroorsaak beduidende konflik met arm landbouers wie nie hulle lewensonderhoud kan verseker as hulle nie saad kan berg vir toekomstige saaiseisoene nie. Dit is een aspek van die problematiek rondom die beskerming van kennisprodukte wat vererger word deur die wetenskaplike onsekerheid wat gepaard gaan met die risiko's van biotegnologie. Terwyl sekere waarnemers vir waaksaamheid pleit in die gebruik van GMOs, is daar ander wat voel dat 'n gebrek aan wetenskaplike bewyse van skade genoegsame gronde is vir die voortsetting van ontwikkelings in biotegnologie. Insgelyks is daar diegene wat meen dat biotegnologie markgedrewe in plaas van menslike behoefte gedrewe is, wat uiteindelik daartoe lei dat ontwikkelende state baie min voordeel daaruit trek. Die Kartagena Protokoloor bioveiligheid is opgestel om van die probleme betrokke by die oorgrens verskuiwing van GMOs aan te spreek. Hoewel dit spesifieke voordele vir ontikkelende state inhou is dit as reguleringsraamwerk beperk in omvang en aanwending. Ontwikkelende state het beperkte beleidsopsies om hulle behoefte om biodiversiteit te beskerm en voedselvoorsiening te verseker, aan te spreek. Dit beteken dat beduidende uitdagings en beperkings hierdie state in die benutting van globale regering van openbare goedere vir die bou van menslike en tegnologiese kapasiteite in die gesig staar.
210

Genmat i fokus : analyser av fokusgruppssamtal om genförändrade livsmedel /

Wibeck, Victoria, January 2002 (has links) (PDF)
Diss. Linköping : Univ., 2002.

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