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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

In vivo siRNA-Transfektion der Lunge und des Bronchialkarzinoms zur Analyse der Hypoxie-induzierbaren Faktoren in der Tumorprogression /

Kamlah, Florentine. January 2007 (has links)
Universiẗat, Diss., 2007--Giessen.
42

New insights into structure and function of type I collagen

Xiong, Xin, January 2008 (has links)
Stuttgart, Univ., Diss., 2008.
43

Expression des Insulin-like-growth-factor-Systems in Rinderplazentomen im Verlauf der normalen Gravidität sowie bei Graviditäten aus In-vitro-Embryoproduktion mit dem pathologischen Erscheinungsbild "Large Offspring Syndrome"

Richterich, Peter January 2008 (has links)
Zugl.: Giessen, Univ., Diss., 2008
44

Expression des Insulin-like-growth-factor-Systems in Rinderplazentomen im Verlauf der normalen Gravidität sowie bei Graviditäten aus In-vitro-Embryoproduktion mit dem pathologischen Erscheinungsbild "Large Offspring Syndrome"

Richterich, Peter January 1900 (has links) (PDF)
Zugl.: Giessen, Univ., Diss., 2008
45

Zeitliche Expressionsprofile der Zytokine-Interleukin-1-beta, Interleukin-6 und transforming growth factor-beta 1 mittels Real-time-Polymerase-Kettenreaktion (rt-PCR) im Myelonkompressionsmodell der Ratte

Ringelstein, Marius January 2007 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss.
46

Expression des Insulin-like Growth Factor Systems in Rinderplazentomen im Verlauf der normalen Gravidität sowie bei Graviditäten aus in-vitro Embryoproduktion mit dem pathologischen Erscheinungsbild "Large Offspring Syndrome"

Richterich, Peter. January 2008 (has links) (PDF)
Universiẗat, Diss., 2008--Giessen.
47

Evaluation of Intestinal Responses to Alternative Protein Sources for Rainbow Trout (Oncorhynchus mykiss)

2015 December 1900 (has links)
Replacement of fish meal as the primary protein source in diets for farmed carnivorous fish is a major priority for sustainability of the aquaculture industry. Three plant-based protein sources (soybeans, field peas, and canola) were investigated to compare their effects on the health and performance of rainbow trout (Oncorhynchus mykiss) and to identify significant anti-nutritional factors (ANFs). Six separate 8-week studies were conducted, over a period of one year, to assess the effects of protein source and processing level (meal versus protein concentrate) at dietary inclusion rates of 0 to 300 g kg-1. Abundance of inflammatory and immune marker transcripts including proliferating cell nuclear antigen (PCNA), immunoglobulin M (IgM), interleukin-1 beta (IL-1β), interleukin-8 (IL-8), and interleukin-10 (IL-10) was evaluated in distal intestinal tissue by quantitative PCR (qPCR) analysis. Activity of the pro-apoptotic enzyme caspase-3 was also assayed in distal intestinal tissue. Transcript abundance was highly variable and no suitable genes for the internal normalization of qPCR data could be identified. As a result, transcript copy numbers were reported per 50 ng of total RNA. At 300 g kg-1 inclusion, soybean meal (SBM) increased abundance of IL-8 and IgM, pea meal (PM) increased abundance of IL-10, and canola protein concentrate (CPC) increased abundance of IL-8. Pea protein concentrate (PPC) reduced IL-8 abundance and caspase-3 activity, while increasing abundance of IL-10. Canola meal (CM) and soy protein concentrate (SPC) did not significantly affect the transcript abundance of any assayed gene. Pearson correlation coefficients were determined between gene transcript abundance, performance parameters, protein source, inclusion level, and ANF content. Specific growth rate (SGR) was negatively correlated with the abundance of IL-1β and IgM. Dietary inclusion of SBM was positively correlated with all assayed proinflammatory markers and negatively correlated with SGR. Inclusion of PM was positively correlated with both SGR and the abundance of IL-10. The inclusion of CM was negatively correlated with average daily feed intake (ADFI) and with the abundance of both IL-8 and PCNA. Inclusion of PPC correlated positively with SGR and negatively with the activity of caspase-3. Correlation between transcript abundance and dietary content of putative ANFs suggested negative correlations between glucosinolate content, proinflammatory cytokine expression, SGR, and ADFI; whereas, isoflavone content was positively correlated with proinflammatory markers and negatively correlated with SGR. In conclusion, although high SBM and CM inclusion levels have been associated with reduced growth performance in trout, only SBM was associated with increased abundance of inflammatory marker transcripts. These contrasting responses may be mediated by CM glucosinolates, which could negatively affect palatability without inducing a pro-inflammatory response. Dietary PM was very well tolerated and may have promoted anti-inflammatory activity. Further processing of protein meals to concentrates markedly reduced any observable negative impact on performance parameters and the abundance of inflammatory marker mRNA transcripts. Interestingly, both PM and PPC were positively correlated with SGR and may contain a beneficial anti-inflammatory component.
48

Identificação de microRNAs na musculatura esquelética de Gallus gallus / Identification of microRNAs from Gallus gallus skeletal muscle

Ana Paula Dini Andreote 10 June 2009 (has links)
Os microRNAs (miRNAs) são pequenos RNAs não codificadores, de cerca de 20 bases de comprimento, capazes de regular negativamente a expressão gênica após a transcrição. A ação regulatória destas moléculas é indispensável para o funcionamento adequado de diversos processos biológicos, dentre eles o desenvolvimento e a manutenção da musculatura esquelética. Com o objetivo de caracterizar a população de miRNAs presentes na musculatura esquelética adulta de frangos, foi construída uma biblioteca de miRNAs a partir do músculo peitoral de indivíduos jovens (21 dias pós-eclosão). Um total de 576 clones foi sequenciado e as sequências obtidas foram agrupadas por similaridade em 98 grupos, dentre os quais 47 corresponderam à miRNAs conhecidos, 30 à outros tipos de RNA e seis à possíveis novos miRNAs. Estes dados poderão subsidiar estudos funcionais subsequentes, que visem entender a função exercida por cada uma destas moléculas na musculatura esquelética. Buscando-se associar a ocorrência e expressão dos miRNAs ao controle da miogênese, foi analisada a expressão de três miRNAs identificados na biblioteca (miR-125b, miR-221 e miR-206), envolvidos na regulação do balanço entre proliferação e diferenciação celular, mecanismo determinante da miogênese. A análise foi realizada por PCR quantitativa em diferentes estádios do desenvolvimento (nove e 17 dias embrionário e 21 dias pós-eclosão) e entre duas linhagens de frango com potencial divergente para crescimento e ganho de massa muscular. Não houve diferença significativa na expressão dos miRNAs entre as linhagens em nenhum dos estádios aferidos, entretanto, foi possível traçar a ontogenia destas moléculas ao longo do desenvolvimento do animal, o que permitiu inferências sobre as condições morfológicas e fisiológicas das células musculares em cada um dos estádios analisados. Por fim, com o objetivo de associar os dados de expressão obtidos para os miRNAs, à variações na expressão de genes alvo, aferimos a expressão de três genes: SRF, Fstl e Pola1; onde o primeiro é regulado pelo miR-133a (cuja expressão não foi aferida devido à questões metodológicas) e os dois últimos pelo miR-206. A análise foi feita também por PCR quantitativa, entre as linhagens e em diferentes estádios do desenvolvimento. Foi possível visualizar, apenas nos estádios embrionários, a relação entre a expressão do miR-206 e seus genes alvo, com uma coerência entre o aumento na expressão do miR-206 e a diminuição na expressão de Pola1 e Fstl1. A determinação do perfil de expressão dos três genes ao longo do desenvolvimento muscular permitiu inferências sobre a ação destas moléculas no balanço entre proliferação e diferenciação nas linhagens de corte e postura / MicroRNAs (miRNAs) represent a class of small and noncoding RNAs, about 20-nucleotides long that negatively regulate gene expression posttranscriptionally. The regulatory action of these molecules is essential for the proper functioning of various biological processes, including the development and maintenance of skeletal muscles. To identify miRNAs that might be important for the skeletal muscle development, we constructed a miRNA library from pectoral skeletal muscle of 21º days after birth chickens. A total of 576 clones were sequenced and these sequences were collapsed into 98 clusters. Sequence analysis identified 47 small RNAs that show significant similarities with published miRNAs, 30 with others noncoding RNAs and six sequences clusters could be identified as potentially novel miRNAs. These data may support subsequent functional studies aimed at understanding the function performed by each of these molecules in skeletal muscle of chicken. To further associate the miRNA presence with the gene expression in the controlling of myogenesis the expression patterns of tree miRNAs identified in the library (miR-125b, miR-221 e miR-206) were analyzed. These miRNAs are involved in the balance between proliferation and differentiation mechanisms that control myogenesis. The expressions of these miRNAs were measured using quantitative RT-PCR. We analyzed samples from two embryos stages (9 and 17 days) and one adult stage (21º days after birth) in two chicken lines with different potential to growth and gain of muscle mass. There were no significant differences between the lines about these miRNAs expression. But, we could predict an overview of these miRNAs expressions during the muscle development of chicken, which allowed inferences about the physiologic and morphologic conditions of the muscles cells in each analyzed stage. Also, to further associate the miRNAs results to variations in the target genes expressions, we analyzed the expression of three genes: SRF, Fstl e Pola1. The first one is target of miR-133a (not analyzed due to methodological problems), and the others are target of miR-206. We analyzed by quantitative RT-PCR different stages and two chicken lines. It was possible to observe, only in the earlier stages, a relationship between the miR-206 expression and the Pola1 and Fstl1 expression, with a consistency between the increased expression of mir-206 and decrease in expression of Pola1 and Fstl1. The determination of the profile of these three gene expressions during the muscle development allowed inferences about the action of these molecules in the balance between proliferation and differentiation process in chicken strains for broiler and layer
49

Mass Spectrometric and Molecular Analyses of Biological Agents In Environmental Compartments

January 2012 (has links)
abstract: This thesis discusses the use of mass spectrometry and polymerase chain reaction (PCR), among other methods, to detect biomarkers of microorganisms in the environment. These methods can be used to detect bacteria involved in the degradation of environmental pollutants (bioremediation) or various single-celled pathogens, including those posing potential threats as bioterrorism agents. The first chapter introduces the hurdles in detecting in diverse environmental compartments in which they could be found, a select list of single-celled pathogens representing known or potential bioterrorism agents. These hurdles take the form of substances that interfere either directly or indirectly with the detection method. In the case of mass spectrometry-based detection, many of these substances (interferences) can be removed via effective sample pretreatment. Chapters 2 through 4 highlight specific methods developed to detect bioremediation or bioterrorism agents in environmental matrices. These methods are qualitative mass spectrometry, quantitative PCR, and quantitative mass spectrometry, respectively. The targeted organisms in these methods include several bioremediation agents, e.g. Pseudomonas putida F1 and Sphingomonas wittichii RW1, and bioterrorism agents, e.g. norovirus and Cryptosporidium parvum. In Chapter 2, I identify using qualitative mass spectrometry, biomarkers for three bacterial species involved in bioremediation. In Chapter 3, I report on a new quantitative PCR method suitable for monitoring of a key gene in yet another bioremediation agent, Sphingomonas wittichii RW1; furthermore, I apply this method to track the efficacy of bioremediation in bioaugmented environmental microcosms. In Chapter 4, I report on the development of new quantitative mass spectrometry methods for two organisms, S. wittichii RW1 and Cryptosporidium parvum, and evaluate two previously published methods for their applicability to the analysis of complex environmental samples. In Chapter 5, I review state-of-the-art methods for the detection of emerging biological contaminants, specifically viruses, in environmental samples. While this summary deals exclusively with viral pathogens, the advantages and remaining challenges identified are also applicable to all single-celled organisms in environmental settings. The suggestions I make at the end of this chapter are expected to be valid not only for future needs for emerging viruses but also for bacteria, eukaryotic pathogens, and prions. In general, it is advisable to continue the trend towards quantification and to standardize methods to facilitate comparison of results between studies. / Dissertation/Thesis / Ph.D. Biological Design 2012
50

Avaliação de alguns microrganismos da microbiota intestinal endógena de crianças eutróficas com sobrepeso e obesas em idade escolar. / Evaluation of some microorganism from endogenous intestinal microbiota of normal weight, overweight and obese schoolchildren.

Aline Ignacio Silvestre da Silva 16 April 2014 (has links)
O objetivo deste trabalho foi analisar comparativamente alguns microrganismos que compõe a microbiota intestinal endógena de crianças eutróficas (30), com sobrepeso (24) e obesas (30) entre 3 a 11 anos, a partir de amostras fecais. Foi realizado o isolamento de espécies de Bacteroides, Parabacteroides e Clostridium; a identificação de B. fragilis e C. perfringens enterotoxigênicos; e a detecção quantitativa por PCR (SybrGreen) de B. fragilis, B.vulgatus, P. distasonis, C. perfringens, C. difficile, Bifidobacterium spp., Lactobacillus spp., Bacteroidales e Clostridium (cluster I). As espécies C. perfringens e B. vulgatus foram as mais isoladas; nenhum isolado B. fragilis foi enterotoxigênico; todos C. perfringens foram classificados como tipo A e destes 8,7% e 12,2% possuiam os genes tpeL e netB, respectivamente. C. perfringens, C. difficile e Bifidobacterium spp. estavam em maior quantidade em crianças eutróficas, enquanto obesos e com sobrepeso apresentaram maior número de Lactobacillus spp. e Bacteroidales. / The aim of this study was to evaluate some microorganism from endogenous intestinal microbiota of normal weight (30), overweight (24) and obese (30) children between 3 and 11 years, from fecal samples. It was performed the isolation of species of Bacteroides, Parabacteroides and Clostridium; the identification of B. fragilis and C. perfringens enterotoxigenic; and the quantitative detection by PCR (SybrGreen) B. fragilis, B. vulgatus, P. distasonis, C. perfringens, C. difficile, Bifidobacterium spp., Lactobacillus spp., Bacteroidales and Clostridium (cluster I). The species C. perfringens and B. vulgatus were the most isolated; no isolated B. fragilis was enterotoxigenic; all C. perfringens were classified as type A and these 8.7% and 12.2% harbored tpeL and netB genes, respectively. C. perfringens, C. difficile and Bifidobacterium spp. were in greater quantity in normal weight children while obese and overweight showed a higher number of Lactobacillus spp. and Bacteroidales.

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