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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.
21

Biodegradace 17alfa-ethinylestradiolu enzymy ligninolytických hub / Biodegradation of 17alfa-ethinylestradiol by enzymes of ligninolytic fungi

Přenosilová, Lenka January 2012 (has links)
This work is aimed at the study of the effect of 17α-ethinylestradiol (EE2) on the production and characteristics of ligninolytic enzymes (laccase, Mn-dependent peroxidase and lignin peroxidase) in I. lacteus, T. versicolor, P. chrysosporium and P. ostreatus cultures grown on two types of liquid media. Enzyme activity production in fungal cultures was affected by the composition of culture medium. In the case of P. chrysosporium, the addition of EE2 to the complex- medium cultures led to a MnP activity stimulation and simultaneously LiP production was partially repressed in these cultures. In the mineral MM medium, no effect of EE2 on enzyme production by P. chrysosporium was observed. In EE2 treated MM cultures of P. ostreatus lower MnP activities were found when compared to biotic controls. In the case of T. versicolor cultures, the addition of EE2 to the complex medium caused laccase and LiP stimulation in the cultures. In the MM medium, however, only laccase production was affected by EE2. I. lacteus MnP production was partially repressed by EE2 in MM medium. In contrast to that, significantly higher MnP activities were detected in complex- medium I. lacteus cultures after the treatment with EE2. Further EE2 degradation by the fungal cultures was studied. The highest degradation effeciency was...
22

Detekce extracelulárních mikroRNA v mateřské cirkulaci - diagnostika a prognostika těhotenských komplikací / Detection of extracellular microRNAs in maternal circulation - diagnosis and prognosis of pregnancy related complications

Ondráčková, Markéta January 2013 (has links)
MicroRNAs (miRNAs) are small noncoding RNAs of length 18 to 25 nucleotides that regulate gene expression posttranscriptionally. Expression of some miRNAs is tissue specific. I assumed that pregnancy induced complications associated with placental insufficiency could be characterized by a unique profil of placental-specific miRNAs in maternal circulation. I measured concentration and gene expression of selected miRNAs (miR-516-5p, miR-517*, miR-518b, miR-520a*, miR-520h, miR-525 and miR-526a) in the plasma of patients with preeclampsia (PE), fetal growth restriction (FGR) and gestational hypertension (GH). The control group consisted of patients with a normal course of pregnancy (FG). I processed 168 plasma samples, the representation of individual diagnosis were as follows: PE 63, FGR 27, GH 23, FG 55. Detection and quantification was carried out by quantitative real-time PCR. I identified three miRNAs with elevated levels in a group of preeclamptic patients: miR-517*, miR-520a* and miR-525. The severity of the PE, which was characterized by a form of the disease (mild or severe PE) and term (before or after the 34th week of pregnancy), did not have a statistically significant effect on the levels of miRNAs. More than a quarter of patients had PE superimposed on previous hypertension. Previous history of...
23

Characterization of genes involved in lignin biosynthesis in Tectona grandis / Caracterização de genes envolvidos na biossíntese de lignina em Tectona grandis

Gómez, Esteban Galeano 06 March 2015 (has links)
Teak tree (Tectona grandis L.f.) has a high value in the timber trade for fabrication of woody products due to its extraordinary qualities of color, density and durability. Despite the importance of this species, genetic and molecular studies available are limited. Also, the lack of molecular information about secondary xylem and tree maturation has hindered genetic exploration of teak. Therefore, gene expression studies and transcriptomic profiling are essential to explore wood formation and lignin biosynthesis through the development and aging of vascular plants. Aiming the gene expression studies, it was essential to identify and clone reference genes for teak. Eight genes were tested, commonly used in qRT-PCR, including TgRP60S, TgCAC, TgACT, TgHIS3, TgSAND, TgTUB, TgUBQ and TgEF1a. Expression profiles of these genes were evaluated by qRT-PCR in six tissue and organ samples (leaf, flower, seedling, root, stem and branch secondary xylem). Stability validation by NormFinder, BestKeeper, geNorm and Delta Ct programs showed that TgUBQ and TgEF1a are the most stable genes to use as qRT-PCR reference genes in teak in the conditions tested. Due to the availability of 12- and 60-year-old teak trees, RNA-seq was performed in diferent organs (seedlings, leaves, flowers, root, stem and branch secondary xylem). A total of 462,260 transcripts were obtained by assembling with \"Trinity\" software. Also, 1,502 and 931 genes differentially expressed were identified for stem and branch secondary xylem, respectively, using DESeq program, and MYB transcription factors, which were characterized. TgMYB1 amino acid sequence displayed a predicted coiled-coil (CC) motif while TgMYB2, TgMYB3 and TgMYB4 showed R2R3-MYB domain. All of them were phylogenetically grouped with several gymnosperms and flowering plants. High expression of TgMYB1 and TgMYB4 in lignified tissues of 60-year-old trees was observed. In this work, the Cinnamyl Alcohol Dehydrogenase (CAD) gene family was also studied. One complete (TgCAD1) and three partial (TgCAD2 to TgCAD4) members were characterized. The four enzymes presented residues for catalytic and structural zinc action, NADPH binding and substrate specificity, consistent with the mechanism of alcohol dehydrogenases. TgCAD3 and TgCAD4 were highly expressed in young and mature sapwood and seem to be duplicated and highly related with lignin biosynthesis. Tree genetic improvement, marker-assisted selection and plant transformation seem to be promising lines of research for the data obtained from this research. This is the first study addressing gene characterization and expression, phylogeny and transcriptomic profiling in teak. / A árvore de teca (Tectona grandis L.f.) tem alto valor no comércio de madeira para a fabricação de produtos lenhosos, devido às suas qualidades extraordinárias de cor, densidade e durabilidade. Apesar da importância desta espécie, são poucos os estudos genéticos e moleculares disponíveis. Também, a falta de informação molecular sobre xilema secundário e maturação da árvore tem dificultado a exploração genética de teca. Assim, estudos de expressão gênica e perfis transcricionais são relevantes para explorar a formação da madeira e a biossíntese de lignina durante o desenvolvimento e envelhecimento das plantas vasculares. Visando os estudos de expressão gênica, foi essencial identificar e clonar genes de referencia para a teca. Foram testados oito genes comumente usados em qRT-PCR, TgRP60S, TgCAC, TgACT, TgHIS3, TgSAND, TgTUB, TgUBQ e TgEF1a. Perfis de expressão destes genes foram avaliados por qRT-PCR em seis amostras de tecidos e órgãos (folhas, flores, plântulas, raiz, xilema secundário de caule e ramo). A validação da estabilidade pelos programas NormFinder, BestKeeper, geNorm e Delta CT mostrou que TgUBQ e TgEF1a são os genes mais estáveis para usar como genes de referência em teca nas condições testadas. Em virtude da disponibilidade de árvores de teca de diferentes idades, entre 12 e 60 anos, foi realizado o RNAseq de diferentes órgãos (plântulas, folhas, flores, raiz, ramos e caules de árvores de 12 e 60 anos). Obteve-se um total de 462.260 transcritos pela montagem com o software \"Trinity\". Foram identificados 1.502 e 931 genes diferencialmente expressos para xilema secundário de caule e ramo, respectivamente, utilizando o programa DESeq e fatores de transcrição MYB, que foram posteriormente caracterizados. A sequência de aminoácidos do TgMYB1 exibiu um motivo \"coiled-coil\" (CC), enquanto TgMYB2, TgMYB3 e TgMYB4 mostraram domínio R2R3-MYB. Todos eles foram filogeneticamente agrupados com várias gimnospermas e angiospermas. Observou-se alta expressão do TgMYB1 e TgMYB4 em tecidos lignificados de árvores de 60 anos de idade. Neste trabalho também foi estudada a família gênica Cinamil álcool desidrogenase (CAD). Foi caracterizado um membro completo (TgCAD1) e três parciais (TgCAD2 a TgCAD4). As quatro enzimas apresentaram resíduos de ação catalítica e estrutural de zinco, de ligação ao NADPH e de especificidade de substrato, em conformidade com o mecanismo conservado de álcool desidrogenases. TgCAD3 e TgCAD4 foram altamente expressos no alburno jovem e maduro e parecem estar duplicados e relacionados com a biossíntese de lignina. O melhoramento genético de árvores, a seleção assistida utilizando marcadores moleculares e a transformação de plantas parecem ser linhas promissoras de pesquisa, a partir dos dados obtidos nesta pesquisa. Este é o primeiro estudo sobre caracterização e expressão gênica, filogenia e perfis transcricionais em teca.
24

Développement d'outils analytiques innovants pour le suivi des populations de Vibrio dans les environnements aquatiques / Development of innovative analytical tools for the monitoring of Vibrio populations in aquatic environments

Silva, Elise Da 08 December 2017 (has links)
Les épisodes de mortalité massive de l’huître creuse Crassostreae gigas observés sur les côtes françaises depuis 2008 ont été associés à certaines espèces appartenant au genre bactérien Vibrio. Ces mortalités, particulièrement intenses et rapides au cœur des lagunes méditerranéennes, atteignent 80 à 100% de la production ostréicole remettant ainsi en cause la pérennité de cette activité. Une surveillance environnementale de ces bactéries apparait donc essentielle et nécessite la mise au point de méthodes d’analyse innovantes, alternatives aux techniques couramment employées, afin de permettre un suivi rapide et en temps réel des Vibrio dans les milieux aquatiques côtiers.Dans ce contexte, l’objectif de cette thèse a été de concevoir des outils analytiques de type génocapteurs pour la détection et la quantification des Vibrio dans les écosystèmes aquatiques. Dans un premier temps, un système basé sur un format d’hybridation « sandwich » reposant sur l’intercalation des acides nucléiques cibles entre une sonde capture immobilisée et une sonde signal marquée, couplé à une détection optique, a été élaboré. Après optimisation des conditions expérimentales, le test développé s’est avéré très sensible avec une limite de détection de 5 ng.µL-1 d’acides nucléiques, ainsi qu’hautement spécifique du genre Vibrio. La méthode a ensuite été appliquée avec succès à la détection des Vibrio dans des échantillons environnementaux, collectés dans la lagune de Salses-Leucate. Un second format d’hybridation, basé sur la compétition entre les acides nucléiques cibles et la sonde capture pour la sonde signal, a ensuite été envisagé en utilisant aussi bien une transduction optique qu’électrochimique. En parallèle, des méthodes de PCR quantitative en temps réel ont été mises au point afin de servir de références pour la validation des génocapteurs. / Mass mortality events affecting the Pacific oyster Crassostreae gigas on French coasts since 2008 have been associated to some Vibrio species. These mortalities, particularly severe and sudden in the mediterranean lagoons, can reach 80 to 100% of the oyster production threatening the sustainability of this activity. An environmental monitoring of these bacteria appears essential and, for this purpose, innovative analytical methods have to be developed as alternative to classical techniques, in order to allow the rapid and in real time monitoring of Vibrio in the coastal aquatic environments. In this context, the objective of the thesis was to design genosensors as analytical tools for Vibrio detection and quantification in aquatic ecosystems. In a first step, a system based on a « sandwich » hybridization format, in which nucleic acid targets were bound between an immobilized capture probe and a labeled signal probe, coupled with an optical detection method, was developed. After experimental condition optimization, the test showed high sensitivity with a limit of detection of 5 ng.µL-1 of nucleic acids and was highly specific to Vibrio spp. The method was then successfully applied to Vibrio detection in environmental samples collected in Salses-Leucate lagoon. A second hybridization format, based on a competition between the targeted nucleic acids and the capture probe for the signal probe has been considered using both optical and electrochemical transductions. Concurrently with the development of genosensors, quantitative real-time PCR have been designed as reference methods.
25

Studies On The Mechanism Of Resistance Against Pyrethroids In Helicoverpa Armigera: Molecular And Proteomic Approach

Konus, Metin 01 September 2012 (has links) (PDF)
Helicoverpa armigera is an insect, causes important economical losses in crops. To reduce this loss, chemical insecticides such as pyrethroids have been commonly used against H. armigera in farming areas all over the world. However, excess and continuous usages of them cause resistance development in H. armigera. Insects develop resistance against applied insecticides by following three main mechanisms / by reducing the amount of insecticide entering into the insect body, developing insensitivity of the insecticide effective site and increasing detoxification metabolism of insecticides such as increased metabolism of them in midgut tissue of H. armigera. Therefore, changes in differentially expressed midgut proteins were analysed at protein level with two-dimensional gel electrophoresis (2D-PAGE) and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) together with examine biochemical activity changes of certain detoxification enzymes such as esterases (EST) and glutathione S-transferases (GST). Moreover, transcriptional level analysis of certain genes from EST and GST systems together with cytochrome P450 monooxygenases (CYP450) system were done with quantitative real-time PCR method, too. According to the comparative proteome analysis, it was found that H. armigera field samples overcome pyrethroid stress mainly by increasing energy metabolism related proteins expressions such as ATP synthase, Vacuolar ATPase A and B and arginine kinase proteins. Furthermore, certain detoxification enzymes such as thioredoxin peroxidase and NADPH cytochrome P450 reductase were up-regulated in Mardin population, suggesting that they were actively participating in response to pyrethroid stress. NADPH cytochrome P450 reductase could play a role in detoxification of toxic pyrethroid metabolites such as 3-phenoxybenzaldehyde. However, while glutathione S-transferases (GSTs) were not found up-regulated in the comparative proteome analysis, biochemical assays (GST-CDNB, GST-DCNB and GST-PNBC) showed significant increases in enzyme activities in the Adana and in the Mardin field population, as compared to the susceptible strain. Furthermore, GST-DCNB and GST-PNBC activities showed significant increase in &Ccedil / anakkale population. As overcoming energy crisis may lead to an increase in oxidative stress, detoxification enzymes (GSTs and thioredoxin peroxidase) might be involved in pathways for eliminating toxic reactive oxygen species such as H2O2. Similarly, although esterases (EST) were not found as differentially expressed, biochemical assays for ESTs showed significant increases in enzymatic activities in the Adana and the Mardin field populations. Thus, ESTs are also proposed to be involved in developing resistance as an initiator of pyrethroid metabolism in H. armigera from Turkey. Quantitative real-time PCR results showed that while CYP9A14 gene expression was up-regulated in all analyzed field populations, CYP9A12 gene expression was up-regulated in both &Ccedil / anakkale and Mardin populations. CYP4S1 gene expression was also up-regulated only in Mardin field population. However, while CYP6B7 gene expression together with CYP9A12 and CYP4S1 genes expressions were down-regulated in Adana population, CYP6B7 gene expression was not significantly changed in both &Ccedil / anakkale and Mardin populations. In addition, GST, GSTX01 and ESTX018 gene expressions were not significantly changed in all field populations in comparison to susceptible population. Therefore, CYP9A14, CYP9A12 and CYP4S1 genes proposed to be involved in detoxification of toxic pyrethroid metabolites possibly through regulation of NADPH cytochrome P450 reductase. In conclusion, it is suggested that one of the main mechanisms of resistance development is increased energy metabolism in the midgut tissue of H. armigera which may be a general prerequisite for compensating the costs of energy-consuming detoxification processes.
26

L’impact du polymorphisme du gène E2 sur la quantification de la charge virale du VPH-16 dans les maladies précancéreuses du col utérin

Azizi, Naoufel 12 1900 (has links)
Le VPH-16 de même que certains VPH, dont le VPH-18, causent le cancer du col utérin. Son intégration dans le génome humain pourrait être un marqueur de progression de l’infection. Les charges virales totale et intégrée sont présentement mesurées en quantifiant par PCR en temps réel les gènes E6 (RT-E6) et E2 (RT-E2-1) du VPH-16. Nous avons évalué l’impact du polymorphisme du gène E2 sur la quantification de l’ADN du VPH-16 dans des spécimens cliniques. Dans un premier temps, le gène E2 de 135 isolats de VPH-16 (123 appartenaient au clade Européen et 12 à des clades non- Européens) fut séquencé. Ensuite, un test de PCR en temps réel ciblant les séquences conservées dans E2 (RT-E2-2) fut développé et optimisé. Cent trente-neuf spécimens (lavages cervicaux et vaginaux) provenant de 74 participantes (58 séropositives pour le VIH, 16 séronégatives pour le VIH) ont été étudiés avec les trois tests E2 (RT-E2-2), E6 (RT-E6) et E2 (RT-E2-1). Les ratios de la quantité d’ADN de VPH-16 mesuré avec RT-E2-2 et RT-E2-1 dans les isolats Européens (médiane, 1.02; intervalle, 0.64-1.80) et Africains 1 (médiane, 0.80; intervalle, 0.53-1.09) sont similaires (P=0.08). Par contre, les ratios mesurés avec les isolats Africains 2 (médiane, 3.23; intervalle, 1.92-3.49) ou Asiatique- Américains (médiane, 3.78; intervalle, 1.47-37) sont nettement supérieurs à ceux obtenus avec les isolats Européens (P<0.02 pour chaque comparaison). Les distributions des quantités de E2 contenues dans les 139 échantillons mesurées avec RT-E2-2 (médiane, 6150) et RT-E2-1 (médiane, 8960) étaient statistiquement différentes (P<0.0001). Nous avons observé que les charges virales totale (odds ratio (OR) OR, 2.16 95% intervalle de confiance (IC) 1.11-4.19), et épisomale du VPH-16 (OR, 2.14 95% IC 1.09-4.19), mais pas la présence de formes intégrées (OR, 3.72 95% IC 1.03-13.4), sont associées aux néoplasies intraepitheliales cervicales de haut grade (CIN-2,3), et ce, en contrôlant pour des facteurs confondants tels que l’âge, le taux de CD4 sanguin, l’infection au VIH, et le polymorphisme de VPH-16. La proportion des échantillons ayant un ratio E6/E2 > 2 pour les femmes sans lésion intraépithéliale (7 de 35) est similaire à celle des femmes avec CIN-2,3 (5 de 11, p=0.24) ou avec CIN- 1 (4 de14, P=0.65). Le polymorphisme du gène E2 est un facteur qui influence la quantification des charges intégrées de VPH-16. / Episomal and integrated HPV-16 loads are currently estimated by quantitation with real-time PCR of HPV-16 E6 (RT-E6) and E2 (RT-E2-1) DNA. We assessed the impact of HPV-16 E2 polymorphism on quantitation of integrated HPV-16 DNA in clinical specimens. First, HPV-16 E2 was sequenced from 135 isolates (123 from European and 12 from non-European lineages). A novel assay targeting conserved HPV-16 E2 sequences (RT-E2-2) was optimized and applied with RT-E6 and RTE2- 1 on 139 HPV-16-positive cervicovaginal lavages collected from 74 women (58 HIV-seropositive, 16 HIV-seronegative). Ratios of HPV-16 DNA copies measured with RT-E2-2 and RT-E2-1 with European (median, 1.02; range, 0.64-1.80) and African 1 (median, 0.80; range, 0.53-1.09) isolates were similar (P=0.08). Ratios obtained with African 2 (median, 3.23; range, 1.92-3.49) or Asian-American (median, 3.78; range, 1.47-37) isolates were greater than those with European isolates (P<0.02 for each comparison). Distributions of HPV-16 E2 copies measured in 139 samples with RT-E2-2 (median, 6150) and RT-E2-1 (median, 8960) were different (P<0.0001). HPV-16 total (odds ratio (OR) OR, 2.16 95% confidence interval (CI) 1.11-4.19), episomal (OR, 2.14 95% CI 1.09-4.19) but not integrated (OR, 3.72 95% CI 1.03-13.4) load, were associated with high-grade cervical intraepithelial neoplasia (CIN-2,3) after controlling for age, CD4 count and HIV, and HPV-16 polymorphism. The proportion of samples with an E6/E2 ratio >2 in women without SIL (7 of 35) was similar to that of women with CIN-2,3 (5 of 11, P=0.24) or CIN-1 (4 of 14, P=0.65). E2 polymorphism was a factor that influenced measures of HPV-16 integrated load.
27

Isolation of Cytokinin Biosynthesis and Metabolic Genes from White Clover (Trifolium repens L)

Evans, Thomas George January 2009 (has links)
The factors influencing senescence in white clover (Trifolium repens L.) are of considerable importance to the pastoral sector of New Zealand’s economy. The plant hormones, ethylene and the cytokinins, have been implicated as having opposing influences on senescence. This project focused on the cytokinins. The rate limiting step in cytokinin biosynthesis is catalysed by isopentenyl transferase (IPT) and the primary enzyme in the degradation of cytokinins is cytokinin oxidase/dehydrogenase (CKX). Both IPT and CKX genes are present as multi-gene families. A reduction in the level of active cytokinins either via a decrease in IPT expression, or an increase in CKX expression, or both, would implicate the cytokinins in developmental leaf senescence in white clover. White clover grows in a sequential pattern with leaves at all stages of development making it a good model for studying leaf development and senescence. A decrease in leaf chlorophyll is used as a marker for the onset of senescence. A micro-scale chlorophyll analysis was developed using the NanoDrop™ thus allowing tissue from the same leaflet to be used for gene expression and chlorophyll measurements. The pattern of chlorophyll changes was similar to that shown by Hunter et al.(1999) and Yoo et al.(2003) in white clover stolons used for ethylene research. Reverse transcriptase PCR (RT-PCR) and BLAST analysis was used to identify five putative IPT genes and seven putative CKX genes from white clover. RT-PCR demonstrated the expression of seven of these genes (TrIPT1. TrIPT13, TrIPT15 TrCKX1, TrCKX2, TrCKX6). Analysis with quantitative real-time PCR showed expression of TrCKX2 increased markedly during leaf expansion and was consistently high during senescence, suggesting a potential role for CKX in facilitating the progression of senescence.
28

Evaluation et développement de marqueurs de la réplication du BK virus en transplantation rénale / Evaluation and development of markers of BK virus replication in kidney transplantation

Solis, Morgane 27 June 2017 (has links)
La néphropathie à BK virus (BKV) est l'une des complications les plus fréquentes de la transplantation rénale. La prise en charge consiste en la réduction préemptive de l'immunosuppression basée sur le suivi de la charge virale, mais cette stratégie n’est pas complètement efficace et augmente le risque de rejet. Dans un premier volet, nous avons évalué la mesure de la charge virale par PCR quantitative en temps réel, permettant de mettre en évidence des facteurs de variabilité comme le polymorphisme du BKV et de valider la technique utilisée pour le suivi de notre cohorte. L’intérêt des anticorps neutralisants (AcNs) anti-BKV en tant que marqueur prédictif de la réplication BKV a ensuite été évalué dans une cohorte de 168 transplantés rénaux. Nous avons montré i) que le virus responsable de l’infection provenait du donneur ; ii) que les AcNs jouent un rôle dans la prévention de la réactivation et le contrôle de la réplication virale et iii) qu’un seuil d’AcNs de 4 log10 permettait de stratifier le risque de réplication BKV. Ce travail ouvre la voie à un suivi personnalisé en fonction du risque de réplication BKV et à de nouvelles approches immunothérapeutiques. / BK virus (BKV)-associated nephropathy is one of the major causes of graft dysfunction and loss in kidney transplant recipients. Since no BKV-specific antiviral therapies are available, management relies on preemptive immunosuppression reduction based on viral load monitoring. However, this strategy does not fully eliminate the risk of nephropathy and can increase the risk of graft rejection. In this work, we evaluated viral load measurement by quantitative real-time PCR in an interlaboratory comparison. Variability factors such as BKV polymorphism or pre-PCR steps have been highlighted and the method used for monitoring our cohort has been validated. The role of anti-BKV neutralizing antibodies (NAbs) as a predictive marker of BKV replication has been investigated in a cohort of 168 kidney transplant recipients. We showed that i) viral infection is caused by the donor strain; ii) NAbs play an essential role in viral replication prevention and control and iii) a NAbs cutoff of 4 log10 allows to stratify BKV replication risk. This work paves the way for personalized monitoring according to BKV replication risk and for new preventive or therapeutic strategies.
29

Expressão diferencial de genes em células foliculares de suínos / Gene expression diferentialy in follicular cells in swine

Miranda, Cristiana Libardi 13 July 2007 (has links)
Made available in DSpace on 2015-03-26T13:42:36Z (GMT). No. of bitstreams: 1 texto completo.pdf: 209546 bytes, checksum: d5ff785c114b2b115999b7a4b5ade9bd (MD5) Previous issue date: 2007-07-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Among the productive traits, the number of the piglets is essential for success in swine production. The ovulation rate is one of the key factors that determine the litter size in pigs and the study of gene expression in the ovary follicles, more precisely in the follicular cells, might cause a big advance in the comprehension of this characteristic. Thus, the objective in this work was to identify the differential expression of the STAR (Steroidogenic Acute Regulator-STAR), GATA (GATA binding protein 4), PGF2&#945; (Prostaglandin F2&#945;), P4R (Progesterone Receptor), FSHR (Follicle Stimulating Hormone Receptor) and CYP19 (Cytochrome Aromatase P450) genes in follicular cells, colleted during the follicular phase in the estrous cycle of three sows with high and three sows with low litter size which comes from a tricross of the Landrace, Large White and Pietrain breeds, throughout the semi quantitative real time PCR (qPCR). In the hyperprolific sows, analyzed in this study, the average of the number of the piglets were 8,51 and for the hypoprolific sows the average was 12,03. For examination if any one related genes above were affecting the ovulation rate in the prolificity rate in the animals studied, the total RNA of the follicular liquid was extracted and than was made two pools with the total RNA of the hypo and hyperprolific sows groups. The total RNA of each pool was used for the first strand cDNA synthesis. The PCR reactions were accomplished using as an endogenous control the &#946;-Actina gene. The primers were generated by sequences in the Pig ESTs data base. The major expression difference was observed for P4R gene, who express 7,73 turns mostly in the animals with low prolificity. The PGF2&#945; gene displayed differential expression of 2,84 times as a large in the hypoprolific animals. The STAR gene expression, that codes for the protein regulating hormone steroids synthesis, was 2.32 turns mostly in the animals with low prolificity sows. The GATA gene expression was 2.31 times as a large in the hypoprolific sows. This gene codes for the GATA binding protein 4 belonging a transcription group factors that are responsible for too many gene expression and diverse cell differentiation types. The CYP19 gene expression taken the enzyme production that is the key factor in the estrogens biosynthesis, the Cytochrome Aromatase P450 (P450aro), for this gene was observed the relative expression of the 2.30 turns mostly in the sows with low prolificity. The FSHR gene expression hasn t achieved the threshold difference established in this study (1.5 times).The STAR, GATA, PGF2&#945;, FSHR, P4R and CYP19 gene expression in the follicular cells has enabled identify difference of expression between sows with low and high prolificity, where the largest difference of expression in relation to the studied genes was verify in the hypoprolific sows, except for the FSHR gene that wasn t considerate differentially express in this work. With views the best agreement about the reproductive phenotypes in swine, it s necessary yet, studies to examine the expression in these and other genes related to female reproductive cycle, in as much as gene expression is dependent, in the midst of another factors, the stage of development of the tissue and the animal age. / Dentre as características produtivas, o número de leitões é fundamental para o sucesso na produção de suínos. A taxa de ovulação é um dos principais fatores que determinam o tamanho da leitegada. Deste modo, o estudo da expressão gênica nos folículos ovarianos, mais precisamente nas células foliculares, pode causar grande avanço no entendimento desta característica. Portanto o presente trabalho foi realizado com o objetivo de identificar a expressão diferencial dos genes STAR (Proteína esteroidogênica regulatória aguda), GATA (Proteína de ligação GATA-4), PGF2&#945; (Prostaglandina F2&#945;), P4R (Receptor de progesterona 4), FSHR (Receptor do hormônio folículo estimulante) e CYP19 (Citocromo aromatase P450) em células foliculares, coletadas durante a fase folicular do ciclo estral de três fêmeas suínas de alta e três de baixa prolificidade, provenientes de um tricross das raças Landrace, Large White e Pietrain, por meio da metodologia de PCR quantitativo em tempo real (qPCR). Nas fêmeas com alta prolificidade, utilizadas neste estudo, a média do número de leitões por leitegada foi 8,51 enquanto para as fêmeas com baixa prolificidade foi de 12,03. Para examinar se algum dos genes relacionados acima afetava as taxas de prolicifidade nos animais deste estudo, o RNA total do líquido folicular foi extraído e, em seguida, fez-se dois pools com o RNA total, sendo um do grupo de fêmeas com alta prolificidade e o outro do grupo com baixa prolificidade. O RNA total de cada um dos pools foi usado na confecção da primeira fita de cDNA. As reações de qPCR foram realizadas usando-se o gene &#946;-Actina como controle endógeno. Os primers foram gerados a partir de seqüências obtidas nos bancos de ESTs de suínos. A maior diferença de expressão foi observada para o gene P4R, que foi expresso 7,73 vezes a mais nos animais com baixa prolificidade. O gene PGF2&#945; apresentou expressão diferencial de 2,84 vezes a mais nas fêmeas hipoprolíficas. A expressão do gene STAR, que codifica para uma proteína reguladora da síntese de hormônios esteróides, foi 2,32 vezes maior nos animais com baixa prolificidade. A expressão do gene GATA foi 2,31 vezes maior nas fêmeas hipoprolíficas. Esse gene codifica para a proteína de ligação GATA-4, pertencente a um grupo de fatores de transcrição responsáveis pela expressão de vários genes e a diferenciação de diversos tipos celulares. A expressão do CYP19 leva à produção de uma enzima chave na biossíntese de estrogênio, a Citocromo aromatase P450 (P450aro), sendo que, para este gene, foi observada uma expressão relativa de 2,30 vezes a mais nas fêmeas de baixa prolificidade. O gene FSHR não atingiu o limiar de diferença de expressão, estabelecido neste estudo (1,5 vezes). A expressão dos genes STAR, GATA, PGF2&#945;, FSHR, P4R e CYP19 nas células foliculares possibilitou a identificação de diferenças de expressão entre as fêmeas com alta e baixa prolificidade, sendo que a maior diferença de expressão para os genes estudados foi verificada nos animais de baixa prolificidade, exceto para o gene FSHR, que não foi considerado diferencialmente expresso nesse trabalho. Com vistas ao melhor entendimento dos fenótipos reprodutivos em suínos, é necessário que estudos sejam conduzifos no sentido de examinar a expressão desses e de outros genes relacionados, durante todo do ciclo reprodutivo das fêmeas, pois, a expressão de um gene depende, dentre outros fatores, do estádio do desenvolvimento do tecido e da idade do animal.
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BK-polyomavirová infekce u pacientů po kombinované transplantaci ledviny a pankreatu / BK-polyomavirus infection in patients after simultaneous pancreas and kidney transplantation

Mindlová, Martina January 2011 (has links)
Introduction. The aim of the study was to introduce a new BKV PCR protocol in our centre and to verify its accuracy as well as to assess the prevalence, risk factors of BK virus replication, course of BKV infection and therapeutic approaches in simultaneous pancreas and kidney (SPK) recipients in order to design a screening protocol. Methods. The results analysed by both Affigene® and Transplantation Virology, Basel PCR protocols were compared. Thereafter 183 SPK patients were examined to assess the prevalence of BK viremia, viruria and BKVN and to identify the risk factors of BKV replication. The cases of retransplantation after a graft loss due to BKVN were retrospectively described. Results. 100 of results were analysed according to the Affigene ® and Transplantation Virology, Basel PCR protocols with the accordance of 95%, Rho = 0,946, 95% CI: 0.920 - 0.963, P<0,0001, Bland-Altman plot analyses: bias Basel PCR protocol/Affigene® BKV trender: -0,1 (mean) *±1.96 SD: -1,6 - 1,3] for both methods. Point-prevalence was assessed in 183 patients; Viruria found in 17,3 %, viremia in 3.8% of patients. High-level viruria >107 copies/mL detected in 3,7% of patiets, high-level virémia >104 in 1,6% of patients simultaneously with high-level viruria. BKVN was found in 0,5% of patients. Diabetes duration...

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