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Dissertations / Theses on the topic 'Gene nod'

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Published: 4 June 2021
Last updated: 1 February 2022

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1

Mavridou, Annoula. "Genetic loci of Rhizobium leguminosarum affecting nod gene expression." Thesis, University of East Anglia, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316102.

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2

Grob, Philipp. "Identification of two homologous two-component regulatory systems, NodV/NodW and NWsA/NwsB, in Bradyrhizobium japonicum and analysis of their role in nodulation and nod gene regulation /." [S.l.] : [s.n.], 1993. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10399.

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3

Eliziário, Fernando Celso Eufigénio. "Análise e sobre-expressão de genes de simbiose de rizóbios de grão-de-bico." Master's thesis, Universidade de Évora, 2016. http://hdl.handle.net/10174/18214.

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Dos genes envolvidos na simbiose entre rizóbios e plantas leguminosas, destaca-se o gene nodD, que codifica o activador da transcrição dos genes de nodulação. No entanto, este gene está pouco estudado em Mesorhizobium. Esta tese compreende o estudo detalhado do gene nodD em espécies de Mesorhizobium noduladoras de grão-de-bico, nomeadamente a investigação da sua diversidade, e a análise do efeito da sua sobre-expressão na eficiência simbiótica. Investigou-se ainda se a sua presença seria capaz de mudar a gama de hospedeiros de um rizóbio. Obteve-se um grande aumento da eficiência simbiótica nas estirpes V-15b e ST-2, transformadas com a cópia extra de nodD. Este trabalho constitui a primeira tentativa de melhorar a eficiência simbiótica de mesorizóbios através da sua transformação com um gene simbiótico, mostrando que esta é uma estratégia promissora para a obtenção de rizóbios inoculantes mais eficientes; Abstract: Among the genes involved in the rhizobia-legume symbiosis, the gene nodD has an important role, since it encodes the major transcriptional activator of nodulation genes. However, this gene is not fully study in Mesorhizobium. This thesis describes the study of the nodD gene from Mesorhizbium species that nodulate chickpea, namely the investigation of its diversity and the analysis of the effect of its overexpression in the symbiotic efficiency. In addition, it was investigated if nodD presence would be able to change the host range in rhizobia. A high improvement in the symbiotic efficiency of the strains V-15b and ST-2 was obtained after transformation with a nodD extra copy. This report describes the first attempt to enhance the symbiotic efficiency through the transformation of mesorhizobia with a symbiosis gene, showing that this approach could be a promising strategy to obtain efficient rhizobia inoculants.
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4

Salie, S. "The symbiotic interaction of Bradyrhizobium japonicum with bambara groundnut and cowpea and the effects of NOD gene-inducers, daidzein and genistein." Bachelor's thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/26054.

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The aim of this project was to investigate whether nodulation, and nitrogen concentration of legumes can be increased by providing additional nod geneinducer compounds. Both daidzein and genistein are nod gene-inducers for rhizobia nodulating cowpea, bambara groundnut, soybean and the common bean.
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5

Mallol, Domínguez Cristina. "Estudi del paper de la sobreexpressió pancreàtica d’IGF-1 en ratolins NOD per contrarestar la diabetis tipus 1." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/285361.

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La diabetis tipus 1 (T1D) és una malaltia autoimmune causada per la destrucció de les cèl·lules β productores d’insulina. La incidència de la T1D està augmentant arreu del món i cada vegada es diagnostica a edats més joves. Aquesta malaltia esdevé clínicament aparent després d’un període preclínic de longitud variable, durant el qual la destrucció autoimmune redueix la massa de cèl·lula β en l’illot pancreàtic de tal manera que els nivells de glucosa en sang no es poden continuar mantenint en un rang fisiològic. Donat que els pacients de T1D requereixen teràpia amb insulina al llarg de tota la seva vida i presenten un elevat risc de complicacions secundàries, noves teràpies preventives o curatives són necessàries. Entre elles, la teràpia gènica ofereix una nova eina de tractament amb grans possibilitats. Entre els possibles gens candidats al tractament de la diabetis, el factor de creixement a la insulina tipus 1 (IGF-1) destaca per les seves propietats immunomoduladores i el seu control sobre la proliferació i supervivència de la massa de cèl·lula β. El nostre laboratori havia descrit prèviament que la sobreexpressió d’IGF-1 a les cèl·lules β d’animals transgènics contrarresta la citotoxicitat i la insulitis induïda pel tractament amb estreptozotocina (STZ) i potencia la regeneració de l’illot. A més, també ha demostrat que l’expressió pancreàtica d’IGF-1 prevé la destrucció de l’illot i la mort de la cèl·lula β en un ratolí transgènic que sobreexpressa interferó-β (IFN-β) a la cèl·lula β, un model d’infiltració limfocítica del pàncrees endocrí. La primera part d’aquest treball es va centrar en l’estudi del paper d’IGF-1 en la preservació de la massa de cèl·lula β en un model espontani de diabetis autoimmune: el ratolí NOD (Non Obese Diabetic). Amb l’objectiu d’estudiar el mecanisme mitjançant el qual la sobreexpressió d’IGF-1 en les cèl·lules β pot prevenir la destrucció autoimmune del pàncrees endocrí, es van generar ratolins NOD transgènics que sobreexpresaven IGF-1 sota el control del promotor RIP-1 (Rat Insulin Promoter) (NOD-IGF1). Els resultats obtinguts van mostrar que els ratolins transgènics NOD-IGF1 eren resistents al desenvolupament de diabetis. Davant una prevalença del 70% en els ratolins NOD, només un 3% dels ratolins NOD-IGF1 desenvolupaven diabetis a les 30 setmanes d’edat. Aquesta prevenció era mediada per un efecte local d’IGF-1 al pàncrees donat que els nivells circulants del factor no estaven augmentats. La reducció en la incidència de diabetis observada en els animals NOD-IGF1 tenia lloc en paral·lel amb una menor infiltració limfocítica dels illots, menor expressió de citoquines inflamatòries i reducció del nombre de cèl·lules β apoptòtiques, suggerint un bloqueig de l’atac autoimmune contra el pàncrees. Aquest bloqueig podria estar mediat per una reducció de les molècules presentadores d’antígens en els illots i un augment de les cèl·lules T reguladores en el pàncrees. Els ratolins NOD-IGF1 preservaven la massa de cèl·lula β amb el temps, presentaven una insulinèmia normal i mostraven un perfil de tolerància a la glucosa normal després de ser administrats amb una càrrega de glucosa intraperitoneal. Tots aquests resultats indicaven que la producció local d’IGF-1 podia protegir les cèl·lules β de la destrucció induïda pel sistema immune i contrarestava la diabetis en una varietat de models de la malaltia que inclou el ratolí amb desenvolupament espontani de diabetis NOD. Per tant, la transferència del gen IGF-1 a pàncrees podria ser una aproximació segura per al tractament de la diabetis tipus 1. A més, estudis realitzats en el nostre laboratori han demostrat que l’administració intraductal de vectors virals adenoassociats de serotip 8 (AAV8) és capaç de transduir de manera eficient i a llarg termini tant el pàncrees exocrí com les cèl·lules β dels illots. Per tant, l’objectiu de la segona part d’aquest treball va ser combinar l’ús dels vectors AAV8 amb els efectes protectors de l’IGF-1 per a desenvolupar una estratègia de teràpia gènica dirigida al pàncrees per a contrarestar la diabetis autoimmune en el ratolí NOD. Amb aquesta finalitat es va generar un vector AAV8 que expressava IGF-1 sota el control del promotor ubic CAG. Per tal de restringir l’expressió d’IGF-1 al pàncrees es van incorporar al constructe les seqüències diana del microRNA 122a (expressat al fetge) i del miroRNA 1 (expressat al cor)a l’extrem 3’-UTR del constructe. Es va observar que l’administració intraductal d’aquest vector era capaç de prevenir la hiperglucèmia en el ratolí NOD. Així, la majoria dels animals administrats amb el vector AAV8 que codificava per IGF-1 van mostrar valors normals de glucèmia al llarg de les 28 setmanes de seguiment i la incidència de diabetis es va veure significativament reduïda. En conjunt, aquest estudi posa de manifest el paper clau d’IGF-1 en la protecció de la massa de cèl·lula β enfront la destrucció autoimmune, i indica que la transferència gènica d’IGF-1 a pàncrees mitjançant vectors AAV podria representar una nova aproximació de teràpia gènica per la diabetis tipus 1.
Type 1 diabetes (T1D) is an autoimmune disease caused by the destruction of insulin-producing β cells. The incidence of T1D is increasing worldwide and is being diagnosed at increasingly younger ages. T1D becomes clinically apparent after a preclinical period of varying length, during which autoimmune destruction reduces the mass of β cells in the pancreatic islets such that blood glucose levels can no longer be maintained in a normal physiologic range. T1D patients require life-long insulin treatment and have a high risk of suffering from medical complications. Therefore, preventative or curative therapies are urgently needed. Among them, gene therapy offers a new tool with great potential treatment opportunities for T1D. Among the possible candidate genes for the treatment of diabetes, the insulin growth factor type 1 (IGF-1) is known for its immunomodulatory properties and its control over the proliferation and survival of β cell mass. Our laboratory has previously reported that the overexpression of IGF-1 in β cells of transgenic animals counteracts cytotoxicity and insulitis induced by streptozotocin (STZ) treatment and promotes islet regeneration. We also described that pancreatic expression of IGF-1 prevents islet destruction and β cell death in a transgenic mouse overexpressing IFNβ (Interferon β) in β cells, a model of lymphocytic infiltration in endocrine pancreas. The first part of this thesis is focused on the study of the role of IGF-1 in the preservation of β cell mass in a spontaneous model of autoimmune diabetes: NOD mouse (Non obese Diabetic). With the aim of studying the mechanism by which the overexpression of IGF-1 in β cells can prevent the autoimmune destruction of the endocrine pancreas, we generated NOD transgenic mice that overexpress IGF-1 under the control of RIP-1 promoter (Rat Insulin Promoter-1) (NOD-IGF1). Our results showed that IGF1-NOD mice were resistant to develop diabetes. As the prevalence of diabetes was of 70% in NOD mice, only 3% of the IGF1-NOD mice developed diabetes at 30 weeks of age. This prevention was mediated by the local effect of IGF-1 in pancreas given that the circulating levels of the factor were not increased. The reduction in the incidence of diabetes observed in NOD-IGF1 animals was in parallel with lower islet lymphocytic infiltration, reduced inflammatory cytokine expression and reduced number of apoptotic β cells, suggesting a blockage of the autoimmune attack against the pancreas. This arrest could be mediated by a reduction of antigen-presenting molecules in islets and an increase in regulatory T cells in the pancreas. IGF1-NOD mice preserved β cell mass with time, showed normal insulinemia and a normal glucose tolerance profile after an intraperitoneal glucose load administration. These results indicate that the local production of IGF-1 protected β cells from the destruction induced by the immune system and counteracted diabetes in a variety of models of the disease, including the spontaneously diabetic NOD mouse. Therefore, IGF-1 gene transfer to the pancreas could be a safe approach for the treatment of type 1 diabetes. Furthermore, studies in our laboratory have shown that intraductal administration of adeno-asociated viral vectors with serotype 8 (AAV8) can efficiently transduce long term both the exocrine pancreas and the islet β cells. Thus, the aim of the second part of this study was to combine the use of AAV8 vectors with the protective effects of IGF-1 to develop a gene therapy approach directed to the pancreas in order to counteract autoimmune diabetes in NOD mouse. For this purpose, we generated an AAV8 vector expressing IGF-1 under the control of the ubiquitous CAG promoter. In order to restrict IGF-1 expression in the pancreas, the target sequences of microRNA 122a (expressed in the liver) and micrRNA 1 (expressed in the heart) were incorporated to the 3’-UTR of the construct. It was observed that the intraductal administration of this vector was able to prevent diabetic hyperglycaemia in NOD mouse. Thus, most animals administered with the AAV8 vector encoding the IGF-1 gene showed normal blood glucose values during 28 weeks and a significant reduction in the incidence of diabetes. In conclusion, this study demonstrates the key role of IGF-1 protecting β cell mass against the autoimmune destruction, and indicates that gene transfer of IGF-1 in the pancreas by AAV vectors could represent a new gene therapy approach for the treatment of type 1 diabetes.
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6

Fornari, Thaís Arouca. "Análise da expressão gênica promíscua no timo de camundongos NOD (non obese diabetic) durante a emergência do Diabetes melitus tipo 1." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-13042009-150027/.

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A tolerância imunológica é a propriedade essencial do sistema imune que controla as reações patológicas contra antígenos do próprio. O timo é visto como o principal órgão envolvido com a indução de tolerância aos antígenos próprios que são expressos pelas células tímicas (tolerância central), enquanto que a indução de tolerância aos antígenos relacionados a outros tecidos (TRAs) tem sido atribuída aos mecanismos de tolerância extratímica (tolerância periférica). Entretanto, a evidência da expressão de TRAs de órgãos e tecidos parenquimais no timo pelas células medulares epiteliais (mTECs) de camundongos e de humanos a qual foi referida como expressão gênica promíscua (PGE) reforçou a concepção de tolerância central de TRAs. O controle molecular dessa expressão tem sido atribuído ao gene Aire (Auto immune regulator) que é um regulador de transcrição. No presente estudo, procurou-se retratar a expressão gênica promíscua no timo de camundongos NOD (Non Obese Diabetic) por meio da análise da expressão gênica em grande escala, ou seja, descrevendo seu transcriptoma usando a tecnologia de cDNA microarrays. Para a análise dos dados utilizamos programas de bioinformática dedicados a microarrays bem como dados de bancos para a caracterização da PGE e susceptibilidade genética ao diabetes melitus do tipo 1 (DM-1). Três conjuntos de resultados puderam ser evidenciados. No primeiro conjunto observou-se a ocorrência da PGE de antígenos tecidos/órgãos parenquimatosos (TRAs) em timos recém removidos e em in vitro em cultura ATOC de camundogos NOD pré-autoimunes e autoimunes (diabéticos). O segundo conjunto de resultados consistiu na análise do efeito da inativação do transcrito de gene Aire na expressão gênica do timo de camundongos NOD in vitro em cultura ATOC. Finalmente, no último conjunto de dados, demonstrou-se que certos genes de TRAs com expressão promíscua, se encontram em regiões cromossômicas de susceptibilidade ao DM - 1 (idds). Como três deles (Il-4, Cd4 e Cdk4) são diretamente relacionados com a patogenia do DM-1 em camundongos foi possível estabelecer um paralelo entre PGE e susceptibilidade genética.
Immunologic tolerance is an essential property of the immune system, which controls immune reactions directed against the body self components. The thymus is seen as the main organ involved with the tolerance induction to self antigens, which are expressed by the thymic cells (central tolerance), while the tolerance induction to the diverse other peripheral tissues and organs is attributed to extra thymic mechanisms (peripheral tolerance). Nevertheless, the evidence for the expression of peripheral tissue related antigens (TRAs) in the thymus by the medullary thymic epithelial cells (mTECs) of mice and humans, which have been termed to as promiscuous gene expression (PGE), has contributed to the concept of central tolerance to TRAs. The molecular control of such gene expression has been attributed to the Aire (autoimmune regulator) gene, which plays a role as a transcriptional regulator. In the present study, we searched to picture PGE in the thymus of NOD (non obese diabetic) mice by means of high throughput gene expression, analyzing the transcriptome by the cDNA microarray method. To analyzing data we used bioinformatics programs dedicated to microarrays and specialized data banks to characterize PGE and genetic susceptibility to type 1 diabetes mellitus (DM-1). Studying pre and autoimmune NOD mice, we evidentiate three sets of results. In the first set, it was observed the occurrence of PGE of parenchymal tissue/organs antigens (TRAs) in fresh thymuses and in thymuses cultured in vitro in adult thymus organ cultures (ATOC). The second set of results consisted in the analysis of the effect of in vitro (ATOC) Aire gene silencing on PGE. Finally, in the third data set, we demonstrated that certain promiscuously expressed genes are positioned in DM-1 genetic susceptibility chromosomal regions (idds). As three of such genes (IL4, Cd4 and Cdk4) are directly associated to the DM-1 pathogenesis in mice, it was possible to establishing a parallel between PGE in the thymus and genetic susceptibility to this autoimmune disease.
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Andersson, Åsa. "B cell repertoire development in normal physiology and autoimmune disease." Doctoral thesis, Umeå universitet, Institutionen för molekylärbiologi (Medicinska fakulteten), 1993. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101767.

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The B cell repertoire in the neonatal immune system (IS) is characterised by reactivity towards self-components, including other immunoglobulin (Ig) V-regions. These properties have been suggested to be a requirement for the development of a normal immune system. DNA sequencing of two interacting Ig idiotypes, derived from neonatal, preimmune mice, demonstrated that such idiotypic connectivity is germ- line encoded and devoid of VDJ junctional diversity. The serum levels of the same Ig idiotypes were studied in normal mice and demonstrated that the expression in serum fluctuated over time in a pattern compatible with a complex dynamic system. In contrast, similar analyses in autoimmune mice or humans demonstrated fluctuations in Ig titers that differed significantly from the healthy individuals. These findings suggested that pathological autoimmunity may be associated with fundamental alterations in the dynamics of natural antibody (ab) expression. This was further investigated in the nonobese diabetic (NOD) mouse, an animal model for human Type I diabetes. Suppression of the early B cell development in the NOD mouse prevented the development of diabetes, suggesting a role for B cells/Igs in the development of diabetes in these mice. Furthermore, neonatal injections of polyclonal Ig preparations or single, monoclonal natural abs inhibited disease induction. The prevention of diabetes development by one such natural ab was demonstrated to be dependent on both the dose injected and the timing of administration. Studies of the B cell repertoire development in NOD mice, compared to normal mice, by DNA-sequence analyses of IgVH rearrangements utilising genes from the most D-proximal Vh family, Vh7183, supported the idea of an aberrant B cell repertoire in this mouse model. Thus, the adult NOD mouse retained a neonatal pattern of Vh7183 rearrangements. This pattern could, however, be "normalised" by neonatal injection of a natural antibody, previously demonstrated to prevent the development of T cell dependent autoimmunity in the NOD mouse.

Diss. (sammanfattning) Umeå : Umeå universitet, 1993, härtill 6 uppsatser


digitalisering@umu
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Bersoult, Anne. "Rôle du récepteur kinase DMI2 dans la perception et la transduction du signal symbiotique Facteur Nod de Sinorhizobium meliloti chez la légumineuse Medicago truncatula." Toulouse 3, 2006. http://www.theses.fr/2006TOU30018.

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Le gène DMI2 joue un rôle central dans l'établissement des symbioses Endomycorhizienne à Arbuscule et Légumineuse-Rhizobium. Il est impliqué dans les étapes précoces de la perception/transduction du signal Nod Factor. DMI2 code un Receptor-Like-Kinase à trois domaines LRR et un domaine NSL dans la partie extracellulaire. Son expression est spécifique des racines et induite dans les primordia nodulaires et la zone de préinfection du nodule suggèrant un rôle dans la préparation des cellules à l'infection. DMI2 est situé dans la membrane plasmique et semble former des homodimères et interagir avec d'autres proteines des étapes précoces de la voie de transduction du signal, DMI1 and LYK3. L'interaction avec NFP reste incertaine. L'analyse fonctionnelle des RLKs NFP, LYK3 et DMI2 montre l'autophosphorylation des kinases LYK3 et DMI2, contrairement à NFP. La transphosphorylation de NFP par DMI2 et/ou LYK3 n'a pas été obtenue. Nous proposons un modèle de transduction des signaux symbiotiques
The DMI2 gene plays a central role for the establishment of the Arbuscular Mycorrhizal and the Legume-Rhizobium symbioses. It is involved in the early steps of perception and transduction of the rhizobial Nod Factor signal. DMI2 encodes a Receptor-Like-Kinase with three LRR and one NSL domain in the extracellular part. DMI2 expression is specific of roots and is induced in nodule primordial and nodule preinfection zone which suggests a role in preparation of the cell to the infection. DMI2 is localised in the plasma membrane and seems to form homodimers and interact with other proteins of the early steps of the signalling pathway, DMI1 and LYK3. Interaction with NFP remains hypothetical. A functional analysis of the NFP, LYK3 and DMI2 RLKs shows autophosphorylation of the LYK3 and DMI2 kinases, contrary to NFP. No evidence of transphosphorylation of NFP by DMI2 and/or LYK3 were obtained. We propose a model of the symbiotic signal transduction
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Duarte, Nádia. "Molecular and cellular mechanisms contributing to the pathogenesis of autoimmune diabetes." Doctoral thesis, Umeå universitet, Medicinsk biovetenskap, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-601.

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Type 1 diabetes is an autoimmune disorder determined both by genetic and environmental factors. The Non-obese diabetic (NOD) mouse is one of the best animal models of this disease. It spontaneously develops diabetes through a process resembling the human pathogenesis. The strong association of NOD Type 1 diabetes to the MHC region and the existence of other diabetes susceptibility loci are also in parallel with the human disease. The identity of the genetic factors and biological function mediated by these loci remain, however, largely unknown. Like in other autoimmune diseases, defects in tolerance mechanisms are thought to be at the origin of type 1 diabetes. Accordingly, defects in both central and peripheral tolerance mechanisms have been reported in the NOD mouse model. Using a subphenotype approach that aimed to dissect the disease into more simple phenotypes, we have addressed this issue. In paper I, we analyzed resistance to dexamethasone-induced apoptosis in NOD immature thymocytes previously mapped to the Idd6 locus. Using a set of congenic mice carrying B6-derived Idd6 regions on a NOD background and vice-versa we could restrict the Idd6 locus to an 8cM region on the telomeric end of chromosome 6 and the control of apoptosis resistance to a 3cM region within this area. In paper II, further analysis of diabetes incidence in these congenic mice separated the genes controlling these two traits, excluding the region controlling the resistance to apoptosis as directly mediating susceptibility to diabetes. These results also allowed us to further restrict the Idd6 locus to a 3Mb region. Expression analysis of genes in this chromosomal region highlighted the Lrmp/Jaw1 gene as a prime candidate for Idd6. Lrmp encodes an endoplasmatic reticulum resident protein. Papers III and IV relate to peripheral tolerance mechanisms. Several T cell populations with regulatory functions have been implicated in type 1 diabetes. In paper III, we analyzed NOD transgenic mice carrying a diverse CD1d-restricted TCR αVa3.2b9), named 24abNOD mice. The number of nonclassical NKT cells was found to be increased in these mice and almost complete protection from diabetes was observed. These results indicate a role for nonclassical NKT cells in the regulation of autoimmune diabetes. In paper IV, we studied the effects of introducing the diverse CD1d-restricted TCR (Va3.2b9) in immunodeficient NOD Rag-/- mice (24abNODRag-/- mice). This resulted in a surprising phenotype with inflammation of the ears and augmented presence of mast cells as well as spleenomegaly and hepatomegaly associated with extended fibrosis and increased numbers of mast cells and eosinophils in the tissues. These observations supported the notion that NKT cells constitute an “intermediary” cell type, not only able to elicit the innate immune system to mount an inflammatory response, but also able to interact with the adaptive immune system affecting the action of effector T cells in an autoimmune situation. In this context the 24abNODRag-/- mice provide an appropriate animal model for studying the interaction of NKT cells with both innate and adaptive components of the immune systemα.
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Lala, Sanjay Govind. "NOD2 gene expression in Paneth cells and monocytes." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1444913/.

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Introduction: Mutations in the NOD2 gene are associated with the development of Crohn's disease, an inflammatory disorder of the gastrointestinal tract. The NOD2 protein induces cellular activation in response to the bacterial antigen muramyl dipeptide (MDP). The NOD2 gene is mainly expressed by circulating blood monocytes although NOD2-associated Crohn's disease involves mainly the terminal ileum. Paneth cells, which are most numerous in the terminal ileum, are specialised intestinal epithelial cells that secrete antimicrobial peptides in response to bacterial products and are critically important in enteric antibacterial defence. I hypothesised that Paneth cells express the NOD2 gene: this thesis describes the expression and quantification of the NOD2 gene in Paneth cells in inflammatory diseases such as Crohn's disease and necrotizing enterocolitis. I also identified factors that regulate NOD2 gene expression in intestinal epithelial cells and peripheral blood mononuclear cells (PBMC).;Methods: In situ hybridisation and immunohistochemistry were used to localize NOD2 mRNA and protein expression in intestinal tissue. Laser capture microdissection (LCM), and calcium chelation followed by mechanical disruption were used to isolate intestinal crypt and villus epithelial cells. Real-time RT-PCR was used to determine NOD2 gene expression in intestinal epithelial cells and PBMC.;Results: NOD2 mRNA and protein expression was readily detected in Paneth cells in normal and Crohn's disease affected terminal ileum NOD2 was also expressed by monocytes, but not by mature macrophages in the lamina propria or within granulomas. NOD2 mRNA levels were enriched in isolated crypt compared to villous epithelial cells, and NOD2 expression was mainly detected in LCM-acquired Paneth cells but not villous epithelial cells. In vitro, tumour necrosis factor alpha (TNFalpha) up-regulates NOD2 gene expression in intestinal epithelial cells. There is a possibility that Paneth cell antimicrobials are reduced in patients with NOD2-related Crohn's disease.;Conclusions: Paneth cells express NOD2 and could therefore play an important and hitherto unrecognized role in the development of NOD2-associated Crohn's disease.
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Oliveira, Luciana Ruano de. "Análise da expressão dos genes nodC e nodG de Rhizobium tropici sob indução com flavonóides pela técnica de PCR quantitativo." Universidade Estadual de Londrina. Centro de Ciências Biológicas. Programa de Pós-Graduação em Microbiologia, 2009. http://www.bibliotecadigital.uel.br/document/?code=vtls000149519.

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O estabelecimento da simbiose rizóbio-leguminosa inicia-se com a excreção, pela planta hospedeira, de compostos de ação quimiotática sobre o rizóbio, facilitando a colonização rizosférica e estimulando o crescimento da bactéria. Geralmente, estes compostos excretados são açúcares, aminoácidos e ácidos dicarboxílicos, que promovem a adesão dos rizóbios aos pelos radiculares das plantas. Simultaneamente a esta adesão, tem início uma troca de sinais moleculares entre o microssimbionte e a planta hospedeira, que libera compostos fenólicos, principalmente flavonóides, responsáveis pela indução da transcrição de genes bacterianos essenciais à nodulação (genes nod, nol e noe). Os rizóbios produzem, então, por meio dos genes de nodulação, os fatores de nodulação (fatores Nod), que são oligossacarídeos lipoquitínicos (LCOs) que induzem modificações radiculares no estágio de pré-infecção, essenciais à infecção do rizóbio para a formação do nódulo e posterior fixação do nitrogênio (N2). O gene nodC é responsável pela biossíntese da estrutura básica do fator Nod, mais especificamente, é responsável pelo controle da etapa de elongação da cadeia principal oligossacarídica. Já o gene nodG é um gene específico do hospedeiro (hsn), responsável pela modificação no esqueleto oligossacarídico do fator Nod. Nesste estudo foi reportadarelatada a resposta transcricional dos genes nodC e nodG na estirpe PRF 81 de Rhizobium tropici, após indução com naringenina e exsudato de sementes de feijão, pela técnica de PCR quantitativo (RT-qPCR). Deste modo, diferentes tratamentos de indução dos genes nod foram realizados. No primeiro experimento, os genes nodC e nodG foram induzidos com naringenina ou exsudato de sementes de feijão por um período de 48 h. Já no segundo experimento, após as células bacterianas atingirem a fase exponencial de crescimento, foi realizado o processo de indução dos genes nod, sendo aplicados os seguintes tempos: 5 min, 15 min, 1 h, 4 h e 8 h. Em seguida, procedeu-se à extração do RNA total de todas as culturas. Os níveis de expressão gênica diferencial foram calculados aplicando-se o método 2-Ct (Livak and Schmittgen, 2001) e a análise dos dados foi feita por estatística descritiva, onde a reprodutibilidade e precisão dos valores de RQ obtidos foram estimados pelos desvios padrão (SD) e coeficiente de variação (CV%) em cada corrida e entre as corridas. Também foi utilizado o programa REST 2008 (Relative Expression Software Tool), versão 2.0.7 (Pfaffl et al., 2002; http://www.gene-quantification.info), o qual testa as diferenças para significância através de um teste randômico, baseado em iterações. Em todas as reações foi utilizado o gene ribossômico 16S como normalizador. Os resultados da quantificação relativa mostraram que, após cinco minutos5 min de incubação, ambos os genes foram significativamente induzidos pelo exsudato, com valores 121,97 e 14,86 superiores ao controle, respectivamente. Níveis de expressão muito inferiores foram observados na presença de naringenina, além disso, a expressão máxima na presença desse indutor foi verificada somente após 8 h de incubação. Esses resultados sugerem que o exsudato de sementes de feijão revelam maior potencial para uma imediata indução dos genes nod em R. tropici PRF 81.
The establishment of rhizobia-legume symbiosis begins with the excretion by the host plant of compounds with chemotatic activity to the rhizobia, facilitating the rhizospheric colonization and stimulating bacterial growth. In general these excreted compounds are sugars, amino acids and dicarboxylic acids that promote the attachment of the rhizobia to the plant root hairs. Simultaneously to this attachment, an exchange of molecular signals between the microsymbiont and the host plant starts, with the plant releasing phenolic compounds, mainly flavonoids, responsible for the induction of the transcription of bacterial nodulation genes (nod, nol and noe genes). Following, rhizobia releases the nodulation factors (Nod factors) that are lipochitin oligosaccharides (LCOs) responsible for the changes in the early stages of the root infection, facilitating the infection of rhizobia that will lead to nodule formation and nitrogen fixation. The nodC gene is responsible for the biosynthesis of the basic structure of the Nod factor, more especifically, it is responsible for controlling the phase of elongation of the oligosaccharides backbone. The nodG gene is a host-specific gene (hsn), responsible for modification in the oligosaccharide backbone of the Nod factor. This study reports the transcriptional response of nodC and nodG genes of strain PRF 81 of Rhizobium tropici, after induction with naringenin and common bean exudate, evaluated by the quantitative PCR technique (RT-qPCR). Different gene induction treatments were applied. In the first experiment, nDeste nodC and nodG genes were induced with naringenin or seed exudates by 48 h. In the second experiment, after bacterial cells reached the exponential phase of growth, induction was achieved by the incubation with naringenin or seed exudates in different periods of time: 5 min, 15 min, 1 h, 4 h e 8 h. Following, total RNA was extracted from all cultures. The levels of differential gene expression were estimated by the method of 2-Ct (Livak and Schmittgen, 2001) and the analyses of the data was performed by using descriptional statistics, with the reproducibility and precision of the RQ values being estimated by the standard deviation (SD) and the coefficient of variatio (CV%) obtained in each assay and among the asssays. The REST 2008 (Relative Expression Software Tool), versão 2.0.7 (Pfaffl et al., 2002; http://www.gene-quantification.info) was also used, to test the statistical significance by means of a random test base on interactions. In all reactions the 16S rRNA gene was used as a normalizer. The results of relative quantification have shown that, after 5 min of incubation, both genes were significantly induced by the exudates, with values of 121,97- and 14,86-fold higher than the control, respectively. Lower levels of expression were observed in the presence of naringenin; furthermore, maximum expression in the presence of this inducer was verified only after 8 h of incubation. These results suggest that common bean seed exudates have a higher potential for a prompt induction of nod gene in R. tropici strain PRF 81. This study reported the transcriptional response of nodC and nodG genes of Rhizobium tropici strain PRF 81 to naringenin and beans seeds exudate, by the RT-qPCR technique. After five minutes of incubation, both genes were significantly induced by the exudate. In contrast, naringenin was not efficient in inducing these genes in any of the times evaluated. These results suggest that the beans seeds exudate show a higher potential for immediate induction of nod genes in Rhizobium tropici PRF 81.
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12

Burn, Joanne Elizabeth. "Analysis of the regulatory nodulation gene nodD of rhizobium leguminosarum." Thesis, University of East Anglia, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329095.

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13

Foerster, Susann. "Gene expression profiling of human lymph node-positive gastric adenocarcinomas." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://dx.doi.org/10.18452/16259.

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In dieser Arbeit wurden Genexpressionsprofile diffuser und intestinaler Magenadenokarzinome mittels Microarray-Technik erstellt. Der intestinale Typ konnte als stark proliferierender Tumor mit signifikanter Überexpression von zellzyklusrelevanten Genen definiert werden, während der diffuse Typ als stark stromaabhängig mit signifikanter Überexpression von Genen der extrazellulären Matrix hervortrat. Thrombospondin 4 (THBS4) wurde dabei als das am stärksten differentiell exprimierte Gen identifiziert, wobei seine mRNA in diffusen Tumoren eminent überexprimiert wird. Immunhistochemische Studien bestätigten diese starke Überexpression auf Proteinebene und zeigten, dass THBS4 eine übermäßig angereicherte extrazelluläre Komponente des Tumorstromas ist. Kolokalisierungsstudien zeigten zudem, dass THBS4-positive Zellen auch positiv für Vimentin und Smooth muscle actin (alpha) sind. Diese Ergebnisse belegen, dass THBS4 von Tumor-assoziierten Fibroblasten (TAF) exprimiert wird. Dies konnte durch zusätzliche in vitro Experimente bestätigt werden, die aufzeigten, dass TAF von diffusen Tumoren eine stärkere THBS4-mRNA Expression aufweisen als normale Fibroblasten des Magens. Abschließend konnten in vitro Kokultur-Studien aufdecken, dass die THBS4-Expression in Fibroblasten durch Tumorzellen diffuser Magentumore transkriptionell stimuliert wird. Metastasenbefall regionaler Lymphknoten (N+) ist bei den meisten Magenadenokarzinomdiagnosen bereits vorhanden. Dieser ist der stärkste derzeit verfügbare Parameter zur Abschätzung der Prognose, reicht aber für eine eindeutige Vorhersage nicht aus. Um ergänzende molekulare Prognoseindikatoren zu identifizieren, wurden aus den Microarray-Daten Gene, deren Expression mit dem klinischen Verlauf von N+ Patienten korreliert, extrahiert. Einige dieser Gene, z.B. RAN binding protein 17 und ras-related associated with diabetes, konnten mittels quantitativer real-time PCR als Marker für verkürztes progressionsfreies Überleben validiert werden.
In this work, gene expression profiles of diffuse and intestinal-type gastric adenocarcinomas were established using the microarray technique. The intestinal type was identified to be a highly proliferative entity with significant overexpression of cell cycle-relevant genes, whereas the diffuse type was proven to be strongly stroma-dependent with significant overexpression of extracellular matrix genes. Thrombospondin 4 (THBS4) was identified as the gene most differentially expressed between the two types with vast mRNA overexpression in diffuse-type tumors. Immunohistochemical studies proved overexpression on protein level and elucidated that THBS4 is a heavily accumulated extracellular constituent of the tumor stroma. Colocalization studies uncovered that THBS4-positive cells are also positive for vimentin and alpha-smooth muscle actin. These data signify that THBS4 is expressed by subpopulations of cancer-associated fibroblasts (CAFs). This was further evidenced by in vitro experiments demonstrating that THBS4 mRNA expression is increased in CAFs of diffuse-type tumors compared to normal gastric fibroblasts. Finally, in vitro coculture studies revealed that transcriptional THBS4 expression in fibroblasts is stimulated by diffuse-type gastric tumor cells. Metastatic involvement of regional lymph nodes (N+) usually accompanies diagnosis of gastric adenocarcinoma and is currently considered the most important parameter for assessment of prognosis. However, estimation of prognosis based on this parameter alone is not sufficiently reliable. In order to identify additional molecular prognosis markers, genes whose expression correlates with clinical outcome of N+ patients were extracted from the microarray data. Via quantitative real-time PCR, several genes, e.g. RAN binding protein 17 and ras-related associated with diabetes, were successfully validated to allow an expression-based stratification of patients with respect to disease-free survival.
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14

Lundholm, Marie. "Functional studies of candidate genes contributing to type 1 diabetes in the NOD mouse." Doctoral thesis, Umeå : Department of Medical Biosciences, Medical and Clinical Genetics, Umeå University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-22401.

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15

Bortolan, Simone. "Avaliação da expressão dos genes nodC, nodW e nopP na estirpe CPAC 15 (=SEMIA 5079) de Bradyrhizobium japonicum pela técnica de RT-qPCR." Universidade Estadual de Londrina. Centro de Ciências Biológicas. Programa de Pós-Graduação em Microbiologia, 2009. http://www.bibliotecadigital.uel.br/document/?code=vtls000149648.

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A fixação biológica do nitrogênio (FBN) na soja ocorre através da simbiose com bactérias (rizóbios), como a espécie Bradyrhizobium japonicum, seu principal simbionte. Contudo, para o estabelecimento da simbiose é necessário troca de sinais moleculares e expressão de vários genes na planta hospedeira e na bactéria. A soja secreta indutores de genes de nodulação, principalmente flavonóides, dentre os quais o mais ativo é a genisteína que induz genes específicos em B. japonicum como o box nodABC, responsável pela formação da estrutura básica dos Fatores de nodulação (Fator Nod), estes por sua vez atuam no processo de infecção do pelo da raiz da planta. Além desses genes, os flavonóides são capazes de induzir outros genes relacionados com o processo infeccioso, como o nodW e o nopP. O primeiro faz parte do sistema de dois-componentes que também ativa os genes nodABC, enquanto o segundo pertence ao Sistema de Secreção Tipo III, responsável pela produção de proteínas efetoras que atuam inibindo a resposta de defesa do hospedeiro. Dentro deste contexto, o objetivo deste estudo foi avaliar a expressão, por RT-qPCR, dos genes nodW, nodC e nopP da estirpe CPAC 15 de B. japonicum, sob indução pelo flavonóide genisteína e por exsudatos de semente de soja composto por vários indutores. A expressão foi avaliada após os períodos de crescimento in vitro por 15 min, 1 h, 4 h, 8 h e 48 h. Os resultados obtidos revelaram que os genes nodW e nodC apresentaram os maiores expressão imediatamente após o contato com o indutor (no tempo de 15 min), sendo maior com genisteína do que com exsudato de soja, indicando que a atividade desses genes pode se fazer necessária no início do processo infeccioso. Em relação ao gene nopP, a expressão induzida por genisteína pode não ter sido diferente entre os tempos analisados devido a variabilidade das repetições, entretanto, células crescidas por 48 hs com genisteína apresentaram um aumento na expressão do gene sugerindo que sua expressão ocorra após um tempo maior de indução pelo flavonóide. Com base nos padrões de expressão observados concluiu-se que a genisteína é um dos principais indutores de genes de nodulação em B. japonicum e dos genes que atuam no processo de infecção, como o gene nopP. Assim, esses genes estudados atuam no processo de nodulação e infecção da soja pelo Bradyrhizobium, os resultados obtidos podem ser úteis em práticas que visam otimizar o processo de nodulação e FBN em soja.
The biological nitrogen fixation (BNF) in soybean occurs through symbiosis with bacteria (rhizobia) and the species Bradyrhizobium japonicum, the main symbiont. However, for the establishment of the symbiosis is necessary exchange of molecular signals and the expression of several genes in the host plant and bacteria. The soybean secret of inducers of nodulation genes, mainly flavonoids, among which the most active is the genistein that induces specific genes in B. japonicum as nodABC box, responsible for the formation of the basic structure of the nodulation factors (Nod factor), these in turn affect the process of infection by the root of the plant. In addition to these genes, the flavonoids are able to induce other genes related to the infectious process, such as nodW and nopP. The first part of a two-component system that activates the genes nodABC, while the second belongs to the Type III Secretion System, responsible for the production of effector proteins that act by inhibiting the response of the host defense. Within this context, the objective of this study was to evaluate the expression by RT-qPCR of genes nodW, nodC and nopP strain CPAC 15, B. japonicum, under induction by flavonoid genistein and soybean seed exudates composed of various inducers. The expression was evaluated after periods of growth in vitro for 15 min, 1 h, 4 h, 8 h and 48 h. The results showed that nodW and nodC genes showed higher expression immediately after contact with the inductor (in time of 15 min), and with more than genistein exudate of soybean, indicating that the activity of these genes can make necessary early in the infectious process. On the nopP gene, the expression induced by genistein may not have been different between the times tested due to variability of repetitions, however, cells grown for 48 hours with genistein showed an increase in the expression of the gene suggesting that its expression occurs after a time greater induction of the flavonoid. Based on observed patterns of expression concluded that genistein is one of the main inducers of nodulation genes in B. japonicum and genes that act in the process of infection, such as gene nopP. Thus, these genes studied acting in the infection and nodulation of soybean by Bradyrhizobium, the results may be useful in practices aimed at optimizing the process of nodulation and BNF in soybean.
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16

Jain, Renu Zaghouani Habib. "Immunotherapy for autoimmune diabetes." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6869.

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The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on April 1, 2010). Vita. Thesis advisor: Habib Zaghouani. "May 2008" Includes bibliographical references.
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17

Santos, Priscila Silveira dos. "Determinação do papel das proteínas NodD1 e NodD2 na ativação dos genes nod em Bradyrhizobium elkanii." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/187249.

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Na simbiose entre soja e bactérias diazotróficas ocorre o processo de Fixação Biológica de Nitrogênio (FBN) no nódulo. Nessa associação há uma comunicação constante, pois a liberação de exsudatos pela planta é percebida pela bactéria, que, então, produz lipo-quito-oligossacarídeos, chamados fatores Nod (FNs), moléculas de sinalização na nodulação. Esses FNs são produtos da atividade dos genes nod bacterianos. Os genes nod regulatórios codificam fatores de transcrição (FTs) responsáveis pela regulação dos genes nod estruturais, que codificam enzimas para a biossíntese dos FNs. Na região promotora dos genes nod atua o FT NodD, que se liga em sequências específicas conservadas, chamadas nod boxes. Essa comunicação abrange a regulação de vários genes, como os genes nod regulatórios nodD1 e nodD2 de Bradyrhizobium elkanii SEMIA 587. Bradyrhizobium elkanii são bactérias Gram-negativas, fixadoras de nitrogênio, usadas comercialmente para a produção de inoculantes na agricultura, devido à eficiência do processo de FBN na simbiose, o que justifica o interesse em torno dessa interação. No micro-organismo modelo Bradyrhizobium diazoefficiens USDA110, as proteínas NodD1 e NodD2, sintetizadas a partir dos genes nodD1 e nodD2, respectivamente, têm ações contrárias. Enquanto NodD1 age como um regulador transcricional positivo dos operons nod e regula a sua própria transcrição, NodD2 atua como um regulador negativo desses operons. Isso despertou o interesse de investigar o papel dessas proteínas em B. elkanii SEMIA 587, com a finalidade de testar se elas apresentam funções semelhantes àquelas demonstradas na estirpe padrão USDA110. Sendo assim, o objetivo do trabalho foi contribuir, através da aplicação de diferentes metodologias, para um melhor entendimento em relação à regulação dos genes nod em B. elkanii SEMIA 587. Para tanto, fragmentos de DNA contendo os genes nodD1 e nodD2 dessa bactéria foram clonados nos vetores pGEM e pGEX-4T2, para produção das proteínas recombinantes em Escherichia coli BL21, a fim de realizar experimentos de retardamento em gel para comprovar a ligação das proteínas NodD1 e NodD2 nos nod boxes identificados nas regiões reguladoras dos respectivos genes, bem como determinar a eficiência de cada ligação. A expressão de ambas as proteínas em E. coli foi visualizada em gel SDS-PAGE e as proteínas estão em fase de purificação. Clonagens posteriores realizadas usando o sistema Gateway® para inserção dos genes nodD1 e nodD2 no vetor de clonagem pENTR foram confirmadas por sequenciamento e recombinadas a dois vetores de levedura (pDEST-22 e pDEST-32). Esses procedimentos visam à execução de ensaios de duplo híbrido para verificar se as proteínas NodD1 e NodD2 são capazes de formar heterodímeros funcionais.
The process of Biological Nitrogen Fixation (BNF) in the symbiosis between soybean and diazotrophic bacteria occurs in the nodule. There is a constant communication in this association. Plant exudates are perceived by the bacteria that produce lipo-chito-oligosaccharides (LCOs), called Nod Factors (NF), signaling molecules in nodulation. These NFs are product of bacterial nod genes activity. Transcription Factors (TFs) are encoded by regulatory nod genes, responsible for structural nod genes regulation. These structural nod genes encode enzymes for NFs biosynthesis. TF NodD acts in the promoter region of nod genes and binds to specific conserved sequences, called nod boxes. The Bradyrhizobium elkanii SEMIA 587 regulatory nod genes nodD1 and nodD2 are involved in this communication. B. elkanii are diazotroph gram-negative bacteria used commercially as inoculants source in agriculture, due to the efficiency of the BNF process in the symbiosis, which justifies the interest regarding this interaction. NodD1 and NodD2 proteins are synthesized by nodD1 and nodD2 and display contrary actions in the model strain B. diazoefficiens USDA 110. While NodD1 acts as a positive transcriptional regulator of nod operons and regulates its own transcription, NodD2 acts as a negative regulator of these operons. These proteins roles in B. elkanii SEMIA 587 aroused the interest of investigating, in order to test whether they have similar functions to those demonstrated in the model strain. Therefore, the goal of this work was to contribute, through the application of different methodologies, to a better understanding regarding nod genes regulation in B. elkanii SEMIA 587. B. elkanii SEMIA 587 nodD1 and nodD2 coding sequences were cloned into pGEM and pGEX-4T-2 vectors. The recombinant proteins were expressed in Escherichia coli BL21 in the order to carry out gel retardation experiments to verify purified proteins binding to the nod boxes identified in nod promoters, as well as the efficiency of each binding. The expressed proteins in E. coli were visualized by SDS-PAGE and are undergoing purification. Subsequent cloning was realized with the Gateway® system for nodD1 and nodD2 insertion into pENTR vector. The constructs were confirmed by sequencing and recombined to yeast vectors (pDEST-22 and pDEST-32).These procedures aim to perform two-hybrid assays to verify if NodD1 and NodD2 are capable of forming functional heterodimers.
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18

Chalmers-Watson, T. A. "The role of the NOD2 gene in the pathogenesis of Crohn's disease." Thesis, University College London (University of London), 2009. http://discovery.ucl.ac.uk/18990/.

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Introduction: Crohn’s disease is characterised by an abnormal inflammatory response possibly induced by components of enteric bacteria, in genetically susceptible individuals. Mutations in the NOD2 gene are strongly associated with Crohn's disease, although the mechanisms by which these mutations cause Crohn’s disease remain unknown. Peripheral blood monocytes (PBMC), a key component of the innate immune system, highly express NOD2, as do intestinal epithelial Paneth cells. The ligand for NOD2 is Muramyl dipeptide (MDP), a component of bacterial peptidoglycan. MDP has been shown to be a powerful priming agent for subsequent stimulation by lipopolysaccharide (LPS) in cell lines and this effect has been linked to NOD2. Studies of primary mononuclear cells in Crohn’s disease comparing the functional effects of the NOD2 mutations had not previously been reported. Aims: To determine the effect of inherited mutations in the NOD2 gene on the cellular responses of freshly extracted PBMC to MDP and other bacterial ligands including mycobacteria. To examine the effect of MDP pre treatment ‘priming’ on PBMC responses to subsequent LPS stimulation in both normal and Crohn’s disease affected patients expressing wild type and mutant NOD2 proteins. Methods: PBMC from healthy controls (n=12), and Crohn’s disease affected patients who were genotypically either wild type (n=12), heterozygous (n=11) or homozygous (n=5) for the common disease-causing NOD2 mutations. PBMC were stimulated with bacterial products in vitro, with or without prior stimulation or ‘priming’ with MDP. The transcription of selected cytokine genes was determined by real time quantitative RT-PCR Results: MDP is a weak stimulant of inflammatory responses in PBMC whereas LPS evoked much stronger responses. Responses to MDP were particularly reduced in PBMC homozygous for the NOD2 mutations. Priming with MDP reduced the inflammatory response of normal PBMC to subsequent LPS stimulation. In PBMC carrying two mutant NOD2 alleles this modulatory effect was reversed and MDP priming caused the inflammatory response to be enhanced. Conclusion: MDP priming significantly modulates responses of monocytes to LPS. This effect is altered in patients with Crohn’s disease – possibly related to mutations in the NOD2 gene. This modulatory effect may explain in part the pro-inflammatory consequence of mutations in the NOD2 gene and could provide mechanistic understanding of how mutations in the NOD2 gene may cause Crohn’s disease.
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Bonaldi, Katia. "Caractérisation de la symbiose Nod-indépendante entre les Bradyrhizobium photosynthétiques et les légumineuses tropicales du genre Aeschynomene." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20185.

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Les Bradyrhizobium photosynthétiques sont capables d'induire la formation de nodules fixateurs d'azote chez certaines légumineuses du genre Aeschynomene. La découverte récente que certaines de ces souches ne possèdent pas les gènes canoniques nodABC indique l'existence d'un nouveau processus symbiotique rhizobium-légumineuse indépendant des facteurs Nod. L'objectif de ce travail de thèse a consisté à avancer dans la compréhension des mécanismes mis en jeu lors de cette nouvelle interaction. Dans un premier temps, à travers différentes approches cytologiques, le processus par lequel la bactérie infecte la plante en l'absence de facteurs Nod a été décrit. Dans un deuxième temps, afin de mettre en évidence les bases moléculaires de cette interaction, une banque de 15 000 mutants Tn5 de la souche ORS278 a été criblée sur plante. Ce criblage a permit l'identification de plus d'une centaine de gènes bactériens intervenant durant le processus symbiotique. Les résultats obtenus nous ont conduits à proposer un modèle dans lequel la mise en place de la symbiose Nod-indépendante impliquerait, d'une part, la synthèse bactérienne d'une cytokinine permettant le déclenchement de l'organogenèse nodulaire, et d'autre part, d'autres signaux bactériens intervenant dans l'étape de reconnaissance avec la plante hôte. Enfin, nous avons mis en place une technique de transformation génétique d'Aeschynomene et validé cet outil à travers l'étude de l'expression hétérologue de la noduline précoce MtENOD11. Il peut à présent être envisagé de conduire des études fonctionnelles sur Aeschynomene en vue de caractériser la voie de signalisation Nod-indépendante
The photosynthetic Bradyrhizobium are able to induce the formation of nitrogen-fixing nodules in some legumes of the Aeschynomene genus. The recent discovery that some of these strains lack the canonical nodABC genes indicates the existence of a new symbiotic rhizobium-legume process that is independent of Nod factors. The aim of this work was to improve our understanding of the mechanisms involved in this new interaction. First, through various cytological approaches, the process by which the bacterium infects the plant in the absence of Nod factors has been described. Second, in order to decipher the molecular basis of this interaction, a library of 15,000 Tn5 mutants of the ORS278 strain was screened on plant. This screening allowed the identification of about one hundred bacterial genes involved in this symbiotic process. These results led us to propose a model in which the establishment of the Nod-independent symbiosis involves, on one han d, the synthesis of a bacterial cytokinin that triggers nodule organogenesis, and on the other hand, others bacterial signals that permit the recognition with the host plant. Finally, we developed a genetic transformation procedure of Aeschynomene and we validated this tool by studying the heterologous expression of the early nodulin MtENOD11. Now, functional studies on Aeschynomene are possible to permit the characterization of the Nod-independent signaling pathway
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20

Ramsey, N. Bruce (Norman Bruce) Carleton University Dissertation Biology. "The rhizobium meliloti JJ1c10 host-range gene nodH : physical, genetic and biochemical analysis." Ottawa, 1990.

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21

Kinose, Daisuke. "NOD2 Gene Polymorphism was associated with prevalence and severity in Japanese COPD patients." Kyoto University, 2012. http://hdl.handle.net/2433/152499.

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22

Gandotra, Sheetal. "The roles of mycobacterial proteasome : and host intracellular pattern recognition receptor NOD2 during tuberculosis in mice /." Access full-text from WCMC, 2008. http://proquest.umi.com/pqdweb?did=1539822201&sid=3&Fmt=2&clientId=8424&RQT=309&VName=PQD.

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23

Champion, Mia Daniele. "Identification of genes that are dosage-sensitive modifiers of nod phenotype and act to properly segregate achiasmate chromosomes /." Connect to Digital dissertations. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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24

Wang, Bo. "Transcriptional regulation of the human NAD(P)H: quinone oxidoreductase gene during oxidative stress." Thesis, University of East Anglia, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262435.

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25

Rana, Amer Ahmed. "Analysis of P351 : a novel gene expressed in the mouse node during early embryogenesis." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419245.

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26

Meidtner, Karina. "Analysis of lipid metabolism-related candidate genes in swine." kostenfrei, 2008. http://mediatum2.ub.tum.de/node?id=629093.

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Mettu, Ramakanth Reddy. "Constructing gene expression based prognostic models to predict recurrence and lymph node metastasis in colon cancer." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=6015.

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Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains xiv, 126 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 123-126).
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28

Santos, Bruno Acácio de Castro Moreira dos. "Small RNAs in gene regulatory networks." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708543.

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29

Wilkinson, James Michael. "Gene expression profiling in lung and lymph node of pigs with different susceptibilities to Glässer's disease." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611576.

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30

Wallerand, Hervé Thiery Jean Paul Chopin Dominique. "Recherche de marqueurs diagnostiques et/ou pronostiques du cancer de la vessie étude des mutations des gènes p53/FGFR3 et de l'expression de la E- et de la N-cadhérine /." Créteil : Université de Paris-Val-de-Marne, 2007. http://doxa.scd.univ-paris12.fr:8080/theses-npd/th0394253.pdf.

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Thèse de doctorat : Biochimie. Biologie cellulaire et moléculaire : Paris 12 : 2005.
Version électronique uniquement consultable au sein de l'Université Paris 12 (Intranet). Titre provenant de l'écran-titre. Bibliogr. : 383 réf.
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31

Böhm, Stefanie. "Non-protein-coding RNA : Transcription and regulation of ribosomal RNA." Doctoral thesis, Stockholms universitet, Institutionen för molekylär biovetenskap, Wenner-Grens institut, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-102718.

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Cell growth and proliferation are processes in the cell that must be tightly regulated. Transcription of ribosomal RNA and ribosomal biogenesis are directly linked to cell growth and proliferation, since the ribosomal RNA encodes for the majority of transcription in a cell and ribosomal biogenesis influences directly the number of proteins that are synthesized. In the work presented in this thesis, we have investigated the ribosomal RNA genes, namely the ribosomal DNA genes and the 5S rRNA genes, and their transcriptional regulation. One protein complex that is involved in RNA polymerase I and III transcription is the chromatin remodelling complex B‑WICH (WSTF, SNF2h, NM1). RNA polymerase I transcribes the rDNA gene, while RNA polymerase III transcribes the 5S rRNA gene, among others. In Study I we determined the mechanism by which B‑WICH is involved in regulating RNA polymerase I transcription. B‑WICH is associated with the rDNA gene and was able to create a more open chromatin structure, thereby facilitating the binding of HATs and the subsequent histone acetylation. This resulted in a more active transcription of the ribosomal DNA gene. In Study II we wanted to specify the role of NM1 in RNA polymerase I transcription. We found that NM1 is not capable of remodelling chromatin in the same way as B‑WICH, but we demonstrated also that NM1 is needed for active RNA polymerase I transcription and is able to attract the HAT PCAF. In Study III we investigated the intergenic part of the ribosomal DNA gene. We detected non-coding RNAs transcribed from the intergenic region that are transcribed by different RNA polymerases and that are regulated differently in different stress situations. Furthermore, these ncRNAs are distributed at different locations in the cell, suggesting that they have different functions. In Study IV we showed the involvement of B‑WICH in RNA Pol III transcription and, as we previously had shown in Study I, that B‑WICH is able to create a more open chromatin structure, in this case by acting as a licensing factor for c-Myc and the Myc/Max/Mxd network. Taken together, we have revealed the mechanism by which the B‑WICH complex is able to regulate RNA Pol I and Pol III transcription and we have determined the role of NM1 in the B‑WICH complex. We conclude that B‑WICH is an important factor in the regulation of cell growth and proliferation. Furthermore, we found that the intergenic spacer of the rDNA gene is actively transcribed, producing ncRNAs. Different cellular locations suggest that the ncRNAs have different functions.

At the time of the doctoral defence the following papers were unpublished and had a status as follows: Paper 2: Manuscript; Paper 3: Manuscript

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32

Gangadharaiah, Dayananda Sagar. "PATTERNS OF DIPEPTIDE USAGE FOR GENE PREDICTION." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1279304144.

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33

Ilg, Kathrin. "Herstellung und molekulare Charakterisierung stabil transduzierter Rattenkardiomyoblasten und humaner epithelialer Vorläuferzellen zum nicht-invasiven Gene imaging : Vergleich von wildtyp und mutanter Herpes Simplex Virus Typ I Thymidinkinase." kostenfrei, 2008. http://mediatum2.ub.tum.de/node?id=656591.

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34

Guo, Man-Yuan. "Mechanisms involved in early Nod Factor signaling in legume root hairs : electrophysiological analyses in Medicago truncatula." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTG092.

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La symbiose entre les légumineuses et les rhizobia est d'une importance majeure dans les écosystèmes terrestres du fait de sa capacité à fixer l'azote atmosphérique. Le dialogue moléculaire entre les deux partenaires, qui mène finalement au développement de nodosités hébergeant les bactéries fixatrices, peut être initié par la liaison des facteurs Nod (NF) sécrétés par les rhizobia aux récepteurs à NF de la membrane plasmatique (PM) des poils racinaires de la légumineuse. Cela déclenche un influx de Ca2+ dans la cellule, suivi d'une cascade d'événements de signalisation ionique, impliquant des changements dans les flux de H+, K+ et Cl- à travers la MP. Mon objectif a été de caractériser les mécanismes moléculaires qui sous-tendent ces premiers événements de signalisation ionique chez la légumineuse modèle Medicago truncatula. En utilisant la technique du patch-clamp sur des protoplastes obtenus par digestion enzymatique ou ablation laser assistée de la paroi cellulaire de poils en croissance, j'ai contribué à caractériser plusieurs conductances ioniques de la MP de ces cellules. Je me suis particulièrement concentrée sur une conductance cationique activée par l'hyperpolarisation membranaire (HACC), particulièrement perméable à Ca2+. Cette conductance est rapidement activée (en moins d'une minute) par l'addition de NF à une concentration physiologique et son activation est dépendante de la présence de récepteurs NFP ("Nod Factor Perception") fonctionnels. Ces résultats suggèrent que c'est cette conductance qui conduit l'influx précoce de Ca2+ déclenché par la perception des NF. Je me suis aussi intéressée à des systèmes de transport cationiques membranaires exprimés dans les poils absorbants de M. truncatula, appartenant aux familles HKT et GLR (Glutamate receptor-like), en tant qu'acteurs potentiels des premiers événements ioniques de signalisation. L'analyse par génétique inverse du rôle de 3 GLR fortement exprimés suggère que ces gènes ne jouent pas un rôle majeur dans la mise en place de la conductance HACC et ne sont pas indispensables à la nodulation. D'autre part, les transporteurs HKT, qui se sont révélés sélectifs de Na+, sont exprimés dans les nodosités, suggérant un rôle dans la symbiose
Symbiosis between legumes and rhizobia is of major importance in terrestrial ecosystems due to its ability to fix atmospheric nitrogen. The molecular dialogue between the two partners, which ultimately leads to development of nodules hosting the N2 fixing bacteria, can be initiated by the binding of Nod factors (NF) secreted by the rhizobial partner on NF receptors at the legume root hair plasma membrane (PM). This triggers a Ca2+ influx through the PM, followed by a cascade of ionic signaling events, involving changes in H+, K+, and Cl- fluxes at the PM. My objective was to characterize molecular mechanisms underlying these early ionic signaling events in the legume model Medicago truncatula. By using the patch-clamp technique on protoplasts obtained either by cell wall enzymatic digestion or laser-assisted ablation from growing root hairs, I have contributed to characterize several ion conductances from this cell type. I especially focused on a cationic conductance activated by membrane hyperpolarization (HACC), uniquely found to be most permeable to Ca2+. This conductance was quickly activated (within less than 1 minute) following NF addition at physiological concentration. Its activation was dependent on the presence of functional NFP (“Nod Factor Perception”) receptors, which suggested that this conductance mediates the early Ca2+ influx triggered by NF perception. In addition, cationic transport systems expressed in M. truncatula root hairs and belonging to the HKT and Glutamate receptor-like (GLR) families were investigated as potential contributors to the early ionic signaling events. Loss-of-function mutant analysis for 3 highly expressed GLRs suggested that these genes did not play major roles in the expression/activity of the HACC conductance, and were not indispensable for nodulation. On the other hand, the HKT transporters, which were found to be Na+-selective, were expressed in nodules, which suggested a role in symbiosis
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Mauermann, Daniel. "Prävalenz der 3020insC Mutation des NOD2/CARD15-Gens bei Patienten mit chronischer Parodontitis." Diss., lmu, 2004. http://nbn-resolving.de/urn:nbn:de:bvb:19-19968.

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36

Fichtbauer, Liesl. "Assoziation zwischen Polymorphismen in den Peroxisome Proliferator-activated Receptor-alpha, -delta und -gamma2 Genen und der Ausdauerleistungsfähigkeit." kostenfrei, 2008. http://mediatum2.ub.tum.de/node?id=626673.

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37

Cheely, Adam Webster Baldwin Albert Sidney. "Regulation and functional impact of lipopolysaccharide induced Nod2 gene expression in the murine epididymal epithelial cell line PC1." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,2647.

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Thesis (M.S.)--University of North Carolina at Chapel Hill, 2008.
Title from electronic title page (viewed Oct. 5, 2009). "... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Biology." Discipline: Biology; Department/School: Biology.
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38

Muys, Bruna Rodrigues. "Caracterização da Estrutura e Regulação dos Genes MGC16121 e CR596471." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-29082013-142331/.

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Os genes MGC16121 e CR596471 localizam-se no cromossomo X (Xq26) entre os loci HPRT1 e PLAC1, uma região rica em genes associados com a reprodução humana. A importância de tais genes reside na possibilidade de estarem envolvidos no desenvolvimento placentário e fetal e de serem expressos em poucos tecidos normais. Camundongos portadores de deleções próximas do gene ortólogo HPRT1 de humanos apresentam cerca de um terço do tamanho dos camundongos selvagens ou em alguns casos são natimortos. No entanto, este fenótipo não é observado quando o gene está mutado. Assim, pode-se supor que o fenótipo anormal das cobaias não é resultado da deficiência do HPRT1, mas sim de genes e/ou microRNAs (miRNAs) próximos a ele. Estes resultados abrem perspectivas em relação ao estudo dos genes MGC16121, CR596471 e miRNAs das vizinhanças. O objetivo deste trabalho foi caracterizar a estrutura, a expressão e o mecanismo de regulação por metilação dos genes MGC16121 e CR596471. Adicionalmente foram analisados quanto ao perfil de expressão e regulação por metilação os miRNAs das vizinhanças (miR-424, 503, 450a, 450b-5p e 542-3p). O gene MGC16121 mostrou-se específico de placenta e também expresso em 50% das 18 linhagens tumorais analisadas. Já CR596471 e os miRNAs das vizinhanças foram mais expressos em placenta do que qualquer outro tecido normal analisado, sendo o primeiro expresso também em 100% das linhagens tumorais avaliadas. Houve correlação positiva e significativa entre todos os genes e miRNAs em relação à expressão em tecidos normais, porém o mesmo não foi observado para linhagens tumorais. A respeito da regulação, os genes CR596471 e MGC16121 e os miRNAs miR-424, 503 e 450a foram regulados negativamente por metilação do DNA em pelo menos uma das três linhagens tratadas com o agente demetilante 5-aza-2-deoxicitidina. Apoiando este fato, os dinucleotídeos CpG das ilhas CpGs situadas próximas às regiões 5 dos genes CR596471 e MGC16121 foram pelo menos em parte desmetilados após o mesmo tratamento.Os dados relativos à estrutura primária dos genes indicam que os transcritos, apesar de serem lncRNAs apresentaram características de mRNAs. Para MGC16121 foi determinado um transcrito composto de 3 éxons e, para CR596471, um transcrito composto de 3 éxons e outro composto de 2 éxons. Os transcritos aqui determinados são relativamente conservados quando comparados a sequências de RNA encontradas em outros mamíferos, principalmente em primatas. Adicionalmente, o transcrito de MGC16121 possui subestruturas secundárias visivelmente semelhantes com aquelas dos transcritos homólogos encontrados em alguns primatas. De acordo com os resultados, o gene MGC16121 pode ser considerado um possível bom marcador para diagnóstico, prognóstico e talvez para terapias contra cânceres. Todavia, mais experimentos devem ser realizados para verificar a função dos genes MGC16212 e CR5976471, além de avaliar mais robustamente a capacidade do gene MGC16121 ser utilizado como ferramenta na medicina contra o câncer.
CR596471 and MGC16121 genes lie on chromosome X (Xq26) between the HPRT1 and PLAC1 loci, a region rich in genes associated with human reproduction. The importance of such genes is the possibility that they might be involved in placental and fetal development, aware that they are expressed in few normal tissues. Deletions in mice around the orthologous gene of human HPRT1 affect their development or lead to stillbirth. However, this phenotype is not observed when this gene is mutated. So we can assume that the abnormal phenotype of mice cannot be due to HPRT1 deficiency, but to genes and/or microRNAs (miRNAs) nearby. These results support the idea of investigating the mechanisms involved in the regulation of the MGC16121 and CR596471 genes, and their neighbor miRNAs. This study aimed to characterize the structure, expression and regulation mechanism by methylation of genes MGC16121 and CR596471. In addition, the expression profile and methylation regulation of the neighbor miRNAs (miR-424, 503, 450a, 450b-5p and 542-3p) were analyzed. MGC16121 was demonstrated to be placenta specific and expressed in 50% of 18 tumor cell lines analyzed. CR596471 and the neighbor miRNAs were more expressed in placenta than in any other normal tissue analyzed. The former was also expressed in all tumor cell lines evaluated. There was significant and positive correlation between all genes and miRNAs regarding normal tissue expression. However, the same was not observed for the tumor cell lines. With respect to regulation, the genes CR596471 and MGC16121, and miRNAs miR-424, 503 and 450a were negatively regulated by DNA methylation at least in one of the three cell lines treated with the demethylating agent 5- aza-2-deoxycytidine. Supporting these results, the CpG dinucleotides from CpG islands located near the CR596471 and MGC16121 5 regions were at least partially demethylated after the same treatment. The data concerning to genes primary structures indicate that the transcripts, despite of being considered lncRNAs, presented mRNAs characteristics. It was determined one transcript for MGC16121 gene which consisted of three exons, and for CR596471 gene, two transcripts were found, one with three exons and other composed of two exons. The transcripts herein determined are relatively conserved when compared to RNAs sequences found in other mammals, mostly in primates. Besides, the MGC16121 transcript presents similar secondary substructures to those found in homologous transcripts from other primate species. According to the results, MGC16121 gene could be considered a possible good biomarker to diagnosis, prognosis and perhaps to therapies against cancers. Nevertheless, more experiments must be accomplished in order to verify the functions of MGC16121 and CR596471 genes, in addition to evaluate more robustly the competence of MGC16121 gene to be used as a tool in medicine against cancer.
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39

Liang, Xiaoyu. "Computational Methods for Cis-Regulatory Module Discovery." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1288578177.

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40

Perera, Rushika. "Genome wide identification of target genes associated with lymph node metastasis in Esophageal Adenocarcinoma." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107901.

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Esophageal cancer (EC) is one of the world's deadliest malignancies. Despite technological advancements in surgery and other therapies, the 5-year survival rate is less than 30%. Due to the lack of reliable diagnostic markers, EC remains an aggressive disease capable of forming secondary tumours in many locations including lymph nodes (LNs). In fact, over 80% of esophageal cancer patients have LN metastasis and the presence of LN metastasis at surgery is one of the greatest predictors of poor survival outcome. The goal of this study was to identify genes associated with the metastatic dissemination of cancer cells from a primary tumour to a regional LN. This could help us understand the mechanisms of LN metastasis and potentially provide therapeutic targets to manage this deadly disease. Laser Capture Microdissection (LCM) was used to obtain pure populations of cancer cells in matched primary tumour and LN metastases from chemo and radiotherapy naïve patients with adenocarcinoma (ADC) of the esophagus. Differences in whole genome expression patterns between primary tumour and LNs were analyzed using cDNA microarrays. Genes involving TNF, NFKβ, Wnt pathways and those associated with immune response have been identified as potential key players in promoting metastasis. Many of these genes are primarily involved in cellular processes such as cellular proliferation, cell migration and cell adhesion. These finding suggest that LN metastasis in esophageal ADC may arise from changes in a cancer cell's ability to interact with new microenvironments and effectively deal with the host's immune system.
Le cancer de l'oesophage (CaO) est une des malignités les plus mortelles connues. Malgré de nombreux avancements de la médecine moderne dans les domaines de la chirurgie et autres thérapies, le pourcentage des gens survivant cinq ans est de moins de 30 %. En raison du manque de marqueurs de diagnostique fiables, le CaO reste une maladie agressive capable de causer la formation de tumeurs secondaires à plusieurs emplacements, dont les ganglions lymphatiques (GL). En fait, plus de 80 % des patients atteints de CaO présentent des tumeurs métastatiques au GL lors de la chirurgie, constituant un indice des plus déterminant dans un pronostique pessimiste. Le but de cette étude était d'identifier les gènes associés à la dissémination métastatique des cellules cancéreuses à partir d'une tumeur primaire vers un GL local. Cette identification des gènes déterminants pourrait s'avérer être cruciale dans la compréhension du mécanisme de métastase au niveau des GL et potentiellement aider à la mise sur pied de soins actifs plus efficaces dans le traitement de cette maladie dévastatrice. La Microdissection au Laser (ML) est utilisée pour l'obtention de populations pures de cellules cancéreuses. La ML est utilisée pour effectuer des prélèvements dans la tumeur primaire ou au niveau des métastases des GL à partir de patients avec adénocarcinome (ADC) de l'oesophage n'ayant pas reçu de chimio et radiothérapie. Les différences dans l'expression du génome entier entre la tumeur primaire et les GL ont été analysées à l'aide d'une puce à ADN microarray. Les gènes incluant les voies métaboliques TNF, NFKβ,Wnt et celles associées avec une réaction immunitaire ont été identifiés en tant que joueurs clés provoquant la métastase. Plusieurs de ces gènes sont impliqués dans les procédés cellulaires tels la prolifération, migration et adhésion cellulaire. Ces constatations suggèrent que les métastases aux GL dans les ADC oesophagiens surviendraient suite à des changements au niveau de l'habileté d'une cellule cancéreuse à interagir avec de nouveaux microenvironnements et efficacement trafiquer le système immunitaire de l'hôte.
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41

Duskey, Jason Thomas. "The development and biological evaluation of Octreotide contatining peptides for receptor mediated non-viral gene delivery." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/4965.

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The ability to deliver DNA to target cells creating therapeutic effects remains an important goal in the field of gene therapy. A majority of clinical trials to overcome this issue have utilized viral vectors due to their efficiency at DNA delivery and ability to create high levels of gene expression. However, their inherent toxicity and a several clinical trials leading to patients contracting new diseases from the treatment have greatly hindered the progress of viral gene therapy. Non-viral gene delivery agents have a much better safety profile, but are also much less efficient at delivering DNA, leading to low gene expression. The reason for this low expression is the numerous barriers that must be overcome to achieve gene expression: circulation, tissue specific accumulation, internalization, release of DNA cargo, and nuclear localization. While peptides are currently being improved upon, enhancing binding and the ability to protect DNA, they are still deficient when it comes to tissue specificity. Numerous targeting methods, including the use of lectins, antibodies, aptamers, and peptides, have been designed to deliver molecules to a specific research. Research to incorporate targeting ligands onto non-viral gene delivery vectors is abundant in the literature; however, successful site specific gene delivery has not been achieved. The somatostatin receptor 2 (SSTR2) ligand, octreotide, is a well-researched eight amino acid peptide that has extensive SAR data available. Also, the receptors have been well characterized and octreotide is used clinically in the radioscintigraphy imaging of brain tumors. While well researched, there are unexplored opportunities to utilize octreotide to enhance non-viral gene delivery vectors. The overall scope of this thesis is to develop and synthesize non-viral gene delivery peptides conjugated to octreotide creating receptor mediated targeting of DNA polyplexes to create tissue specific accumulation. Initial experiments indicated that attachment of octreotide to the polycationic peptide WK18 does not inhibit affinity for the SSTR2 receptor. Therefore, peptides were designed and synthesized to attach octreotide onto polyacridine peptide (Acr-Lys)6. Polyplex characteristics were unchanged by the incorporation of octreotide, and exhibited very low genotoxic effects compared to the in vitro gene delivery agent PEI. Competitive binding assays suggested a stoichiometric, ligand, and temperature dependent accumulation of polyplex on SSTR2 expressing cells, but gene expression could not be achieved. The success of (Acr-Lys)6octreotide, led to the synthesis of a di-maleimide-PEG attached to each end by (Acr-Lys4)3Acr-Lys-Cys or Cys-Gly5octreotide in attempts to create distance, and better ligand availability for the receptor, by expressing octreotide away from the polyplex. Testing of this peptide in PEGylated polyplex ad-mixtures verified that separating the DNA binding peptide from octreotide did lead to better inhibition of binding to DAOY cells in a competitive binding study. However, transfection assays with this compound showed background levels of gene expression. Although gene expression was not achieved, the synthetic strategy to create a molecule incorporating a DNA binding peptide, ligand, and PEG to create better ligand presentation to its receptor when incorporated into PEGylated polyplexes is an important step in the design of gene delivery vectors.
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42

Tajouri, Lotfi, and n/a. "Gene Expression Analysis and Genetic Studies in Multiple Sclerosis." Griffith University. School of Health Science, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20060111.123933.

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Multiple Sclerosis (MS) is a neurodegenerative disease of the central nervous system (CNS). As part of this disorder the myelin sheath undergoes degeneration, leading to alterations in the conductivity of axons, and impaired function. The onset of the disease occurs in young adults and clinical pathology is characterised by varying severity. These include i) Relapsing Remitting MS (RR-MS), ii) Secondary Progressive MS (SP-MS) and iii) Primary Progressive MS (PP-MS). MS is more prevalent in women and accounts for more than two thirds of all MS sufferers. MS is considered to be a multifactorial disorder with both genetic and environmental components. The prevalence of MS is dependent on geographical localisation, with lower sunlight exposure linked to higher prevalence. Also, studies show an increased risk in close relatives, or in identical twins, indicating a significant genetic component to the disorder. There are a number of genes that may plausibly be involved in MS pathophysiology. These include myelin-related genes, such as the myelin basic protein (MBP), immune-related genes, such FC receptor and osteopontin, and heat shock proteins such as xb crystallin. These candidate genes have been implicated in a variety of ways but usually through immunological and/or genetic studies. One of the most consistent findings in recent years has been the association of disease with alterations in the specific major histocompatibility complex (MHC) localised to chromosome 6p21.3, and includes MHC I, II, III. Genome wide screens have permitted the identification of loci in the genome, which are associated with MS susceptibility. The number of genes involved in MS is unknown and several case-control association studies have been undertaken to reveal the involvement of potential candidate genes. In general terms, current research is aimed at determining allelic variation of candidate genes. Such genes have been implicated in MS because they reside within susceptible regions of the chromosome associated with MS or they have a plausible potential pathophysiological role in MS. Candidate loci investigated in this study, for association with MS susceptibility, include members of the nitric oxide synthase family of metabolic proteins (inducible NOS, iNOS/NOS2A and neuronal NOS, nNOS), methylenetetrahydrofolate reductase (MTHFR), catechol-O-methyl transferase (COMT), and vitamin D receptor (VDR). The MS population used in all studies consisted of over 100 MS cases and gender, age and ethnicity matched controls. In our study of inducible and neuronal NOS genes, PCR based assays were developed to amplify a region of both promoters that contained known microsatellite variation. Supporting phyisological data suggests that the neuroinflammatory aspects of MS are associated with aberrant NO production, which may be due to aberrant regulation of NOS activity. Specific amplified products were identified by fluorescent capillary electrophoresis and allele frequencies were statistically compared using chi-squared analysis. In the nNOS and iNOS study, no association was identified with allele frequency variation and MS susceptibility (nNOS: ?2=5.63, P=0.962; iNOS: ?2=3.4; P=0.082). Similarly, no differences in allele frequencies were observed for gender or clinical course for both markers (Pvalue greater than 0.05). In short, results from this study indicate that the NOS promoter variations studied do not play a significant role in determining susceptibility to MS in the tested population. The COMT and MTHFR genes are localised at 22q12-13 and 1p36.3 respectively, regions of the genome that have been found to be positively associated with MS susceptibility. In our research, we set out to examine the G158A change in the 4th exon of the COMT gene. This functional mutation leads to an amino acid change (valine to methionine) that is directly associated with changes in the activity of COMT. The MTHFR enzyme plays a role in folate metabolism, and can be implicated in the turnover of homocysteine. Previous investigations have shown that high levels of homocysteine are encountered in MS patients, where it is also linked to demyelination in the CNS. In our study the aim was to examine the C677T variation (alanine to valine amino acid change) in the exon 4 coding region of the MTHFR gene and the G158A variation in the COMT gene. Restriction fragment length polymorphism (RFLP) analysis and gel electrophoresis was used to identify specific alleles for both COMT and MTHFR. However, as with the NOS study, no specific association was identified between MS susceptibility and variation for either of the tested COMT or MTHFR (Pvalue greater than 0.05) variants. In a final genomic investigation of the MS population, three variations in the VDR gene were analysed for association with MS susceptibility and pathology. Using RFLP analysis, three VDR variants were investigated with genotypes detected using the Taq I, Apa I and Fok I restriction enzymes. In contrast to previous genotypic analyses, this study did show a positive association, specifically between the functional variation in exon 9 of the VDR gene and MS (Taq I, 2= 7.22, P= 0.0072). Interestingly, the Apa I variant of VDR was also found to be associated with MS ( 2=4.2, P=0.04). The Taq I and Apa I variants were also found to be in very strong and significant linkage disequilibrium (D'=0.96, Pvalue less than 0.0001) and their associations were more prominent with the progressive forms of MS (SP-MS and PP-MS). In addition to genotypic analysis of a clinical population, additional research was undertaken to identify novel targets for MS susceptibility studies. Global gene expression analysis was undertaken using comparative subtractive fluorescent microarray technology to examine differences in gene activity (expression) in age and sex matched MS plaque tissue and anatomically matched normal white matter (NWM). MS plaques were obtained post mortem from MS sufferers with no drug history in the last two months before death and matched anatomically to healthy white matter from donors with no previous neurological disorders. Target arrays consisted of 5000 cDNAs and analysis was conducted using the Affymetrix 428 scanner. In this way, 139 genes were shown to be differentially regulated in MS plaque tissue compared to NWM. Of these, 69 genes showed a common pattern of expression in the chronic active and acute plaque tissues investigated (Pvalue less than 0.0001, a=0.73); while 70 transcripts were uniquely differentially expressed ( 1.5-fold) in either acute or chronic active lesions. To validate the gene expression profile results, quantitative real time reverse transcriptase (RT) PCR (Q-PCR) analysis was performed. 12 genes were selected because they were shown to be differentially expressed by array analysis in this study, or because of their involvement in MS pathology. These included transferrin (TF), superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), glutathione S-transferase pi (GSTP1), crystallin, alpha-B (CRYAB), phosphomannomutase 1 (PMM1), tubulin beta-5 (TBB5), inositol 1,4,5-trisphosphate 3-kinase B (ITPKB), calpain 1 (CAPNS1), osteopontin (SPP1 or OPN), as well as the signal transducer and activator of transcription 1 (STAT1) and protein inhibitor of activated STAT1 (PIAS1). Both absolute (copy number) and comparative differences in the relative levels of expression in MS lesions and NWM were determined for each gene. The results from this study revealed a significant correlation of real time PCR results with the microarray data, while a significant correlation was also found between comparative and absolute determinations of fold. As with the results of array analysis, a significant difference in gene expression patterning was identified between chronic active and acute plaque pathologies. For example, a up to 50-fold increase in SPP1 and ITPKB levels in acute plaques contrasted with the 5-fold or less increase in chronic active plaques (P less than 0.0.1, unpaired t-Test). Of particular note, gamma-amino butyric acid receptor ?2 (GABG2), integrin ?5 (ITGB5), complement component 4B (C4B), parathyroid hormone receptor 1 (PTHR1) were found up-regulated in MS and glial derived neurotropic factor ?2 (GDNFA2), insulin receptor (INSR), thyroid hormone receptor ZAKI4 (ZAKI4) were found down-regulated in MS. Data also revealed a decreased expression of the immune related genes STAT1 and PIAS1 in acute plaques. In conclusion, this research used both genomic analysis and technologies in gene expression to investigate both known and novel markers of MS pathology and susceptibility. The study developed tools that may be used for further investigation of clinical pathology in MS and have provided interesting initial expression data to further investigate the genes that play a role in MS development and progression.
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43

Segovia, Ramos Nathaly Verónica. "Synthesis of novel poly(β-aminoester)s (pBAEs) as innovative non-viral vectors for efficient nucleic acid delivery." Doctoral thesis, Universitat Ramon Llull, 2014. http://hdl.handle.net/10803/283445.

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Gene therapy has potential therapeutic applications for the treatment of many diseases like cancer, monogenetic diseases, vascular disease, among others. Although the majority of protocols in gene therapy employ viral vectors due to their high transfection efficiency, increasing concerns about their immunological response prompts the development of safe and effective non-viral delivery systems. Poly(β-aminoester)s (pBAEs) are promising non-viral vectors due to their polyester nature results in an attractive biocompatible profile due to their high biodegradability and reduced toxicity. Here we present a novel family of pBAEs, which incorporate terminal oligopeptides, capable of condensing both DNA and siRNA into particles with nanometric size. Firstly, in vitro experiments were performed to evaluate the ability of this new pBAEs to efficient delivery both DNA and siRNA, for up- and down-regulation of a target gene, respectively. Results demonstrated that the oligopeptide incorporation at the termini of pBAEs improved transfection efficiency and biocompatibility when compared to basic pBAEs and commercially available transfection agents. Moreover, nanoparticles prepared with this new family of pBAEs showed different intracellular localization, such as perinuclear or cytoplasmatic, depending on the oligopeptide composition. In addition, specific formulation of pBAEs showed different transfection efficiency depending on the cell line, which revealed that chemical composition of the oligopeptides have a deep effect on transfection. Secondly, siRNA-pBAEs nanoparticles were succesfullly incorporated into hydrogel scaffold for local and sustained release of siRNA. Release studies demonstrated that siRNA was sustainably released due to nanoparticle stabilization within the hydrogel. Finally, in vivo results demonstrated that the local delivery system proposed here was able to silence luciferase expression, in a murine breast cancer model, over a long period of time achieving higher silencing efficiency than a commercial in vivo transfection agent.
La terapia génica presenta potenciales aplicaciones terapéuticas para el tratamiento de muchas enfermedades como el cáncer, enfermedades monogénicas, enfermedad vascular, entre otras. Aunque la mayoría de protocolos de terapia génica empleen vectores virales, debido a su alta eficacia de transfección, crecientes preocupaciones debido a su activación de respuesta inmunológica motivan al desarrollo de sistemas de transportes no virales que sean seguros y eficaces. Poli(β-aminoestere)s (pBAEs) son prometedores vectores no virales debido a que su naturaleza de poliéster resulta en un atractivo perfil de biocompatibilidad debido a su alta biodegradabilidad y baja toxicidad. Este trabajo desarrolla una nueva familia de pBAEs, los cuales presentan oligopéptidos terminales, capaces de condensar tanto ADN como siRNA en partículas de tamaño nanométrico. En primer lugar, se realizan experimentos in vitro para evaluar la habilidad de estos nuevos pBAEs para transportar eficazmente tanto DNA como siRNA, para incrementar o disminuir la regulación del gen de interés, respectivamente. Los resultados demuestran que la incorporación de oligopéptidos en las zonas terminales de pBAEs mejoran la eficacia de transfección y la biocompatibilidad, cuando se comparan con pBAEs sin modificar y agentes de transfección disponibles comercialmente. Además, las nanopartículas preparadas con esta nueva familia de pBAEs muestran diferente localización intracelular, como perinuclear o citoplasmática, dependiendo de la composición oligopeptídica. Asimismo, las formulaciones específicas de pBAEs muestran diferentes eficiencias de transfección dependiendo de la línea celular, lo que demuestra que la composición química de los oligopéptidos tiene una gran influencia en la transfección. En segundo lugar, se demuestra la capacidad de encapsular las nanopartículas preparadas con siRNA y pBAEs en un hidrogel adhesivo con la idea de lograr una liberación local y prolongado de siRNA. Los estudios de liberación realizados demuestran que el siRNA se libera de manera prolongada debido a la estabilización de las nanopartículas en el hidrogel. Finalmente, la aplicación del hidrogel dopado con nanopartículas in vivo demuestra que el sistema local de liberación propuesto en este trabajo es de silenciar la expresión de la luciferasa, en un modelo de cáncer de mama murino, durante un largo período tiempo consiguiendo mejores eficacias de silenciamiento que un agente comercial de transfección in vivo.
La teràpia gènica té potencials aplicacions terapèutiques per el tractament de moltes malalties com el càncer, malalties monogenètiques, malalties vascular, entre altres. Encara que la majoria de protocols de teràpia gènica utilitzin vectors virals, degut a la seva alta eficàcia de transfecció, creixents preocupacions per la seva activació de resposta immunològica motiven al desenvolupament de sistemes de transports no virals que siguin segurs i eficaços. Els Poli(β-aminoester)s (pBAEs) són prometedors vectors no virals ja que la seva naturalesa de polièster resulta en un atractiu perfil de biocompatibilitat per la seva alta biodegradabilitat i baixa toxicitat. Aquest treball desenvolupa una nova família de pBAEs, els quals presenten oligopèptids terminals, capaços de condensar tant ADN com siRNA en partícules de mida nanomètrica. En primer lloc, es realitzen experiments in vitro per tal d'avaluar l'habilitat d’aquests nous pBAEs per transportar eficaçment tant DNA com siRNA, per incrementar o disminuir la regulació del gen d'interès, respectivament. Els resultats demostren que la incorporació de oligopèptids a les zones terminals de pBAEs milloren l'eficàcia de transfecció i la biocompatibilitat, quan es comparen amb pBAEs sense modificar i agents de transfecció disponibles comercialment. A més, les nanopartícules preparades amb aquesta nova família de pBAEs mostren diferent localització intracel • lular, com ara perinuclear o citoplasmàtica, depenent de la composició oligopeptídica. Així mateix, les formulacions específiques de pBAEs mostren diferents eficiències de transfecció depenent de la línia cel • lular, la qual cosa demostra que la composició química dels oligopèptids té una gran influència a la transfecció. En segon lloc, es demostra la capacitat d’encapsular les nanopartícules preparades amb siRNA i pBAEs en un hidrogel adhesiu amb l’idea d’assolir un alliberament local i prolongat de siRNA. Els estudis d'alliberament realitzats demostren que el siRNA s’allibera de manera perllongada a causa de l'estabilització de les nanopartícules en el hidrogel. Finalment, l’aplicació de l’hidrogel dopat amb les nanopartícules in vivo demostra que el sistema local d'alliberament proposat en aquest treball és de silenciar l'expressió de la luciferasa, en un model de càncer de mama murí, durant un llarg període de temps aconseguint millors eficàcies de silenciament que un agent comercial de transfecció in vivo.
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44

Taylor, Kristen Hawkins. "Genetic analyses of bovine CARD15, a putative disease resistance gene." Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/219.

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Through a binding partner the CARD15 gene activates NF-kB, a molecule with a role in the initiation of the inflammatory immune response. The gene is highly conserved in both structure and function in human and mouse and has recently been implicated as a disease resistance gene in Crohn's disease and Blau Syndrome in human. The gene's relationship to disease and its conservation between species suggests that it may also have a conserved role in bovine disease resistance. To elucidate the potential role of bovine CARD15 in disease resistance, the gene was characterized in cattle. Bovine CARD15 is located 4.2 cR5000 telomeric to ADCY7 on chromosome 18. It spans ~30 kb and is comprised of 12 exons, 11 of which are coding. Bovine CARD15 is expressed in many tissues, but is most abundant in peripheral blood leukocytes. An extensive comparative analysis between the bovine, mouse and human CARD15 genes revealed high levels of inter-species conservation in sequence, genomic structure and protein domains. Conserved putative regulatory motifs were identified in the three species comparison of the 5'UTR, 3'UTR and the intronic sequences flanking exons. Additionally, diverse regulatory motifs were identified in each of the species indicating an evolutionary divergence in the mechanisms of regulation of gene expression. To assess the extent of genetic diversity within bovine CARD15, 41 individuals from nine breeds representing two subspecies were sequenced and screened for polymorphisms. Thirty-six single nucleotide polymorphisms (SNPs) were identified including 26 within the gene transcript. Haplotypes were estimated for each individual and parsimonious SNP sets were identified with which the multi-locus Bos taurus and Bos indicus haplotypes may be reconstructed. There was a significantly higher rate of substitutions within Bos indicus than in Bos taurus. A significantly higher rate of nonsynonymous to synonymous substitutions was found in Bos taurus indicating that positive Darwinian selection is acting on the gene within this subspecies. Association analyses were performed between these SNP loci and haplotypes with Johne's disease. No overwhelming evidence for a simple causal relationship was detected. Assays are provided to screen populations of cattle for variation in the CARD15 gene.
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45

Sykes, Michelle Christine. "Regulation of endothelial gene transcription by shear stress in a." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24824.

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Thesis (Ph.D.)--Biomedical Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Jo, Hanjoong; Committee Member: Griendling, Kathy; Committee Member: Harrison, David; Committee Member: Wang, May; Committee Member: Yoganathan, Ajit.
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46

Stults, Dawn Michelle. "STRUCTURAL INSTABILITY OF HUMAN RIBOSOMAL RNA GENE CLUSTERS." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/68.

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The human ribosomal RNA genes are critically important for cell metabolism and viability. They code for the catalytic RNAs which, encased in a housing of more than 80 ribosomal proteins, link together amino acids by peptide bonds to generate all cellular proteins. Because the RNAs are not repeatedly translated, as is the case with messenger RNAs, multiple copies are required. The genes which code for the human ribosomal RNAs (rRNAs) are arranged as clusters of tandemly repeated sequences. Three of four catalytic RNAs are spliced from a single transcript. The genes are located on the short arms of the five acrocentric chromosomes (13, 14, 15, 21, and 22). The genes for the fourth rRNA are on chromosome 1q42, also arranged as a cluster of tandem repeats. The repeats are extremely similar in sequence, which makes them ideal for misalignment, non‐allelic homologous recombination (NAHR), and genomic destabilization during meiosis , replication, and damage repair. In this dissertation, I have used pulse‐field gel electrophoresis and in‐blot Southern hybridization to explore the physical structure of the human rRNA genes and determine their stability and heritability in normal, healthy individuals. I have also compared their structure in solid tumors compared to normal, healthy tissue from the same patient to determine whether dysregulated homologous recombination is an important means of genomic destabilization in cancer progression. Finally, I used the NCI‐60 panel of human cancer cell lines to compare the results from the pulsed‐field analysis, now called the gene cluster instability (GCI) assay, to two other indicators of homologous‐recombination-mediated genomic instability: sister chromatid exchange, and 5‐hydroxymethyl‐2’deoxyuridine sensitivity.
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47

Pettini, Tom. "The role of novel long non-coding RNAs in Hox gene regulation." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-role-of-novel-long-noncoding-rnas-in-hox-gene-regulation(c8e44900-3ac0-40be-8ec6-b50179381d17).html.

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Whole genome transcriptome analysis has revealed that a large proportion of the genome in higher metazoa is transcribed, yet only a small proportion of this transcription is protein-coding. One possible function of non-coding transcription is that it enables complex and diverse body plans to evolve through variation in deployment of a relatively common set of protein-coding genes. Functional studies suggest that long non-coding RNAs (lncRNAs) regulate gene expression via diverse mechanisms, operating in both cis and trans to activate or repress target genes. An emerging theme common to lncRNA function is interaction with proteins that modify chromatin and mediate epigenetic regulation. The Hox gene complexes are particularly rich in lncRNAs and require precise and fine-tuned expression to deploy Hox transcription factors throughout development. Here we identify and functionally characterize two novel lncRNAs within the D. melanogaster Hox complex, in the interval between Scr and Antp. We use nascent transcript fluorescent in-situ hybridization (ntFISH) to characterize the embryonic expression patterns of each lncRNA with respect to flanking Hox genes, and to analyze co-transcription within individual nuclei. We find that the transcription of one lncRNA, ncX, is an initial response to early transcription factors and may activate Scr expression, while transcription of the other lncRNA, ncPRE is consistent with activation and/or maintenance of Scr expression. ntFISH performed in D.virilis embryos revealed the presence of a lncRNA ortholog with highly similar expression to ncX, indicating functional conservation of lncRNA transcription across ~60 million years of evolution. We identify the ncPRE lncRNA locus as a binding site for multiple proteins associated with Polycomb/Trithorax response elements (PREs/TREs) and show that DNA encoding the ncPRE lncRNA functions as a bona fide PRE, mediating trans-interactions between chromosomes and silencing of nearby genes. We find that transcription through the ncPRE DNA relieves silencing, suggesting a role for endogenous transcription of the ncPRE lncRNA in relieving Polycomb-silencing and enabling Scr activation. We demonstrate that both lncRNA transcripts are required for proper Scr expression, and over-expression of either lncRNAs from ectopic genomic loci has no effect on Scr expression, but ectopic expression at the endogenous locus is associated with ectopic Scr activation, indicating that the lncRNA-mediated regulation functions locally at the site of transcription on the chromosome. ncX may mediate transvection effects previously observed at the Scr locus, independent of the protein Zeste. Together our results support a model of competing mechanisms in the regulation of Scr expression - a background of Polycomb repression acting from the ncPRE locus, which in the first thoracic segment is counteracted by lncRNA transcription and Trithorax binding to ncPRE, enabling activation and maintenance of Scr expression. This work provides a functional insight into the complex regulatory interactions between lncRNAs and epigenetic mechanisms, essential to establish and maintain the precise expression pattern of Hox genes through development.
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48

Khorsand, Sourkohi Behnoush. "Gene delivery strategies for enhancing bone regeneration." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6447.

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There exists a dire need for improved therapeutics to achieve predictable and effective bone regeneration. Non-viral gene therapy is a safe method that can efficiently transfect target cells, therefore is a promising approach to overcoming the drawbacks of protein delivery of growth factors. The goal of this study was to employ cost-effective biomaterials to deliver genetic materials (DNA or RNA) in a controlled manner in order to address the high cost issues, safety concerns, and lower transfection efficiencies that exist with protein and gene therapeutic approaches. To achieve our goal, we set several aims: 1) To assess the bone regeneration capacity of polyethylenimine (PEI)-chemically modified ribonucleic acid (cmRNA) (encoding bone morphogenetic protein-2 (BMP-2)) activated matrices, compared to PEI-plasmid DNA (BMP-2)-activated matrices. 2) To explore the osteogenic potential of cmRNA-encoding BMP-9, in comparison to cmRNA-encoding BMP-2. 3) To use collagen membranes as integral components of a guided bone regeneration protocol and to enhance the bioactivity of collagen membranes by incorporating plasmid DNA (pDNA) or cmRNA encoding bone morphogenetic protein-9 (BMP-9). 4) To test whether the delivery of pDNA encoding BMP-2 (pBMP-2) and fibroblast growth factor-2 (pFGF-2) together can synergistically promote bone repair in a leporine model of diabetes mellitus, a condition that is known to be detrimental to union. 5) To investigated whether there is a synergistic effect on bone regeneration following delivery of pBMP-2 and pFGF-2, insulin and/or vitamin D. These investigations together provided new insights regarding the appropriate treatment methods for patients with fractures. Here we develop and test a non-viral gene delivery system for bone regeneration in challenging animal models utilizing a scaffold carrying PEI-nucleic acid complexes. We utilized three kinds of pDNA encoding either BMP-2, BMP-9 or FGF-2 as well as two kinds of cmRNA encoding either BMP-2 or BMP-9 formulated into PEI complexes. The fabricated nanoplexes were assessed for their size, charge, in vitro cytotoxicity, and capacity to transfect human bone marrow stromal cells (BMSCs). The in vivo functional potency of different nanoplexes embedded in scaffolds was evaluated using a calvarial bone defect model in rats, diaphyseal long bone radial defects in a diabetic rabbit model and intramuscular implantation in a diabetic rat. The results indicate that our non-viral gene delivery system induced migration and differentiation of resident cells to enhance bone regeneration. Together these findings suggest that scaffolds loaded with non-viral vectors harboring cmRNA or pDNA encoding osteogenic proteins may be a powerful tool for stimulating bone regeneration with significant potential for clinical translation.
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49

Ruggeri, Rosario Fabio <1975&gt. "Ruolo dei geni NOD2, IL23R ed ATG16L in una popolazione di pazienti siciliani con malattia di Crohn." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3838/.

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50

Kalluru, Vikram Gajanan. "Identify Condition Specific Gene Co-expression Networks." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1338304258.

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