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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.
171

"Células mononucleares de sangue de cordão umbilical e de sangue periférico estimulado com fator de crescimento granulocítico (G-CSF) : análise da proliferação e de apoptose in vitro" / Mononuclear cells from umbilical cord blood and from granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood. Analysis of proliferation and apoptosis in vitro

Ribeiro, Andreza Alice Feitosa 08 September 2003 (has links)
Células mononucleares de sangue de cordão umbilical (SCU) e sangue periférico mobilizado (SPM) com G-CSF, foram cultivadas in vitro com citocinas, na presença ou não de estroma de medula óssea. Os objetivos foram avaliar a capacidade proliferativa de células progenitoras, a ocorrência de apoptose e expressão de integrina. Nas culturas sem estroma, a celularidade aumentou 5 vezes (SCU) e não se alterou nas de SPM. O total de células CD34+ caiu em ambas culturas. Com estroma, o total de células nucleadas aumentou 7 vezes (SCU) e 2,3 vezes (SPM). O total de células CD34+ permaneceu o mesmo. A apoptose foi menor nas culturas de SCU. A expressão de integrina caiu, na população de células CD34+ e de CD45+ / Mononuclear cells from umbilical cord blood (UCB) and G-CSF mobilized peripheral blood (MPB), were cultured in vitro, in the presence of cytokines, with or without bone marrow stroma. The aims were to evaluate the proliferative response of progenitor cells, occurrence of apoptosis and expression of adhesion molecule. In cultures without stroma, cellularity increased 5-fold for UCB, but has not changed for MPB. The number of CD34+ cells has dropped in both culture. With stroma, total nucleated cells had a 7-fold increse (UCB) and a 2,3-fold (MBP), however, CD34+ cells number has not changed. Apoptosis was lower in UCB culture. The expression of integrin decreased, in the CD34+ and CD45+ population
172

Niveaux de vitamine a (retinol et acide retinoïque) mesurés dans le sang de cordon ombilical et dévéloppement rénal des nouveau-nés

Manolescu, Daniel-Constantin 08 1900 (has links)
RÉSUMÉ: Introduction : La Vitamine A (rétinol, ROL) et son métabolite l’acide rétinoïque (AR) sont essentielles pour l’embryogénèse. L’excès comme l’insuffisance d’AR sont nocives. L’AR est régularisé dans l’embryon par des gènes spécifiques (ALDH, CRABP, CYP). Hypothèse : Les grandes variations d’AR dans le plasma des adultes normaux, nous ont orienté à mesurer les rétinoïdes (ROL et RA) dans le sang de cordon ombilical, pour évaluer des corrélations avec des polymorphismes des gènes impliquées dans le métabolisme de l’AR et le développement rénal-(RALDH2, CRABP2, CYP26A1; B1). Vérifier pour des corrélations entre ces rétinoïdes et/ou avec la taille de reins à la naissance. Méthodes : Extraction du ROL et RA du sang de cordon ombilical de 145 enfants et analyse par HPLC. Le volume des reins a été mesuré par ultrasonographie et l’ADN génomique leucocytaire extrait (FlexiGene DNA-Kit). 10 échantillons d’ADN ont été exclus (qualité). Les htSNP : ALDH1A2, CRABP2, CYP26A1;B1 du génome humain (HapMap) ont été séquencés et génotypés (Sequenom iPlex PCR).Des testes bio-statistiques des fréquences génotypiques et alléliques ont été effectués (Single-Locus, χ2, Kruskal-Wallis, Allelic-Exact).Des corrélations (ROL, RA, SNPs, V-reins) ont été analysés (Kendall-tau /Oakes). Résultats : La Δ RA (0.07-550.27 nmol/l) non corrélé avec la Δ ROL (51.39-3892.70 nmol/l). Il n’y a pas d’association ROL ou RA avec les volumes des reins ou avec les SNPs/ CYP21A1;B1. Corrélations trouvées : 1. (p=0.035), polymorphisme génétique ALDH1A2-SNP (rs12591551:A/C) hétérozygote/CA, (25enfants, 19%) avec moyennes d’AR (62.21nmol/l). 2. (p=0.013), polymorphisme CRABP2-SNP (rs12724719:A/G) homozygote/AA (4 enfants, 3%) avec hautes valeurs moyennes d’AR (141,3 nmol/l). Discussion-Conclusion : Les grandes ΔRA suggèrent une variabilité génique individuelle du métabolisme de ROL. Les génotypes (CA)-ALDH1A2/ SNP (rs12591551:A/C) et (AA) -CRABP2/SNP (rs12724719:A/G) sont associés à des valeurs moyennes hautes d’AR, pouvant protéger l’embryogénèse lors d’une hypovitaminose A maternelle. Mots clé: sang de cordon ombilical, ROL-rétinol, AR-acide rétinoïque, HPLC, SNP- polymorphisme, ALDH1A2, CRABP2, CYP26A1,développement rénal,embryogénèse. / ABSTRACT Introduction: Vitamin A (retinol, ROL) modulate the embryogenesis thorough RA, its metabolite. Excess or deficiency being pathologic, the RA is tight regulated in the embryo thorough specific genes (ALDH, CRABP, CYP, etc.) important for Vitamin A metabolism. Hypothesis: High RA variations in healthy adults plasma, oriented to ROL, RA evaluation in human cord blood, in regard of possible correlations with polymorphisms of genes involved in RA metabolism and kidney development (RALDH2, CRABP2, CYP26A1,B1). Correlations between ROL and RA and/or with birth kidney size might also occur. Methods: Cord blood ROL and RA were extracted and HPLC analysed, from 145 Montreal healthy newborns. Kidney volumes already measured by ultrasonography. Genomic leucocytary DNA extraction was performed with FlexiGene DNA-Kit. 10 samples excluded (DNA quality). htSNP choices: ALDH1A2, CRABP2, CYP26A1;B1 were made on HapMap human genome. Sequencing, genotyping (Sequenom iPlex PCR) was made for these genes eventual SNPs. Biostatistics tests for genotype and allelic frequencies (Single-Locus, χ2, Kruskal-Wallis, Allelic-Exact) and Kendall-tau /Oakes analysis for eventual ROL, RA, SNPs, V-reins correlations, were performed. Results: No correlation found between Δ RA (0.07-550.27 nmol/L) and Δ ROL (51.39-3892.70 nmol/L). No association ROL or RA with kidney volumes nor with SNPs/ CYP21A1;B1. Found correlations: 1. (p=0.035), polymorphism ALDH1A2-SNP (rs12591551:A/C) heterozygous/CA, (25babies, 19%) with RA (mean ~62.21nmol/L). 2. (p=0.013), polymorphism CRABP2-SNP (rs12724719: A/G) homozygous/AA (4babies, 3%) with RA (mean~141, 3 nmol/L). Discussion/Conclusion: Big Δ RA not correlated with Δ ROL suggests individual genetic variance on RA metabolism. Genotypes (CA)-ALDH1A2/SNP (rs12591551:A/C) and (AA)-CRABP2/SNP (rs12724719: A/G) are associated with high cord blood RA mean and may be embryogenesis protective in a maternal hypovitaminosis-A, environment. Key words: umbilical cord blood, ROL-retinol, AR-retinoic acid, HPLC, SNP- polymorphism, ALDH1A2, CRABP2, CYP26A1,kidney development,embryogenesis. / Note d'excellence 10%: « Le Jury, à l'unanimité, juge ce mémoire excellent et le classe parmi les 10% des mémoires de la discipline » - selon le Rapport définitif du jury d'éxamen d'un mémoire de maîtrise.
173

"Células mononucleares de sangue de cordão umbilical e de sangue periférico estimulado com fator de crescimento granulocítico (G-CSF) : análise da proliferação e de apoptose in vitro" / Mononuclear cells from umbilical cord blood and from granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood. Analysis of proliferation and apoptosis in vitro

Andreza Alice Feitosa Ribeiro 08 September 2003 (has links)
Células mononucleares de sangue de cordão umbilical (SCU) e sangue periférico mobilizado (SPM) com G-CSF, foram cultivadas in vitro com citocinas, na presença ou não de estroma de medula óssea. Os objetivos foram avaliar a capacidade proliferativa de células progenitoras, a ocorrência de apoptose e expressão de integrina. Nas culturas sem estroma, a celularidade aumentou 5 vezes (SCU) e não se alterou nas de SPM. O total de células CD34+ caiu em ambas culturas. Com estroma, o total de células nucleadas aumentou 7 vezes (SCU) e 2,3 vezes (SPM). O total de células CD34+ permaneceu o mesmo. A apoptose foi menor nas culturas de SCU. A expressão de integrina caiu, na população de células CD34+ e de CD45+ / Mononuclear cells from umbilical cord blood (UCB) and G-CSF mobilized peripheral blood (MPB), were cultured in vitro, in the presence of cytokines, with or without bone marrow stroma. The aims were to evaluate the proliferative response of progenitor cells, occurrence of apoptosis and expression of adhesion molecule. In cultures without stroma, cellularity increased 5-fold for UCB, but has not changed for MPB. The number of CD34+ cells has dropped in both culture. With stroma, total nucleated cells had a 7-fold increse (UCB) and a 2,3-fold (MBP), however, CD34+ cells number has not changed. Apoptosis was lower in UCB culture. The expression of integrin decreased, in the CD34+ and CD45+ population
174

Gene expression of tendon markers in mesenchymal stromal cells derived from different sources

Burk, Janina, Gittel, Claudia, Heller, Sandra, Pfeiffer, Bastian, Paebst, Felicitas, Ahrberg, Annette B., Brehm, Walter January 2014 (has links)
Background: Multipotent mesenchymal stromal cells (MSC) can be recovered from a variety of tissues in the body. Yet, their functional properties were shown to vary depending on tissue origin. While MSC have emerged as a favoured cell type for tendon regenerative therapies, very little is known about the influence of the MSC source on their properties relevant to tendon regeneration. The aim of this study was to assess and compare the expression of tendon extracellular matrix proteins and tendon differentiation markers in MSC derived from different sources as well as in native tendon tissue. MSC isolated from equine bone marrow, adipose tissue, umbilical cord tissue, umbilical cord blood and tendon tissue were characterized and then subjected to mRNA analysis by real-time polymerase chain reaction. Results: MSC derived from adipose tissue displayed the highest expression of collagen 1A2, collagen 3A1 and decorin compared to MSC from all other sources and native tendon tissue (p < 0.01). Tenascin-C and scleraxis expressions were highest in MSC derived from cord blood compared to MSC derived from other sources, though both tenascin-C and scleraxis were expressed at significantly lower levels in all MSC compared to native tendon tissue (p < 0.01). Conclusions: These findings demonstrate that the MSC source impacts the cell properties relevant to tendon regeneration. Adipose derived MSC might be superior regarding their potential to positively influence tendon matrix reorganization.
175

Thermisch schaltbare Hydrogele - Synthese - Charakterisierung - Anwendung

Gramm, Stefan 14 August 2006 (has links)
Gegenstand dieser Arbeit war die Synthese von thermisch schaltbaren Kammcopolymeren auf Basis von N-(Isopropylacrylamid) (NiPAAm) und Polyethylenglykolmakromonomeren (PEGMA). Die intensive Charakterisierung der aus diesen Copolymeren hergestellten Schichten und deren Anwendung als Zellkultursubstrate war ein weiteres Forschungsziel dieser Arbeit. Die mit Hilfe der neuartigen Schichten erhaltenen Zellkultursubstrate wurden anhand verschiedener adhärenter Zelllinien erfolgreich getestet. Alle getesten Zelltypen (Mausfibroblasten, humane Endothelzellen der Nabelschnurvene und humane korneale Endothelzellen) proliferierten auf den angebotenen Zellkultursubstraten bei 37°C und konnten durch senken der Temperatur geerntet werden.
176

IL-17A induced response and synergy with otherproinflammatory cytokines in human endothelial cells

Salin, Julia January 2021 (has links)
Cardiovascular diseases are a broad group of diseases, such as heart attack and heart failureaffecting the cardiovascular system. The primary cause of cardiovascular diseases isatherosclerosis, and its progression is brought about by oxidative stress and a complex chronicinflammation reaction cascade. Of central importance are proinflammatory cytokines, regulatedby multiple factors, including interleukin (IL) 17A. This project aims to investigate the effectof IL-17A on the inflammatory response of human vascular endothelial cells by quantifyingchemokine C-X-C motif ligand-1 (CXCL1) release when exposed or not to otherproinflammatory mediators such as TNF-𝛼, IL-6 and IL-1β. To investigate this, humanumbilical cord endothelial cells were cultured and then stimulated with IL-17A alone or incombination with other cytokines, namely IL-6/sIL6R, IL-1β, or TNF-𝛼. After an appropriateincubation time following the stimulations, the supernatants of the cells were collected, and theamount of CXCL1 was analysed with ELISA or qPCR, respectively. At a lower concentration(10ng/ml), IL-17A failed to induce a significant level of CXCL1 release from endothelial cells.However, IL-17A + TNF-𝛼 (5ng/ml) greatly enhanced, higher than inductions from individualtreatments combined, level of CXCL1 release from endothelial cells. Furthermore, combiningIL-17A with IL-1β or IL-6 induced non-abundant and abundant upregulation in CXCL1 release,respectively. On transcription level, the amount of CXCL1 mRNA induced by IL-17A alonewas non-significant, but stimulation with TNF-𝛼 and IL-17A + TNF-𝛼 induced significantlyupregulated expression of CXCL1. In conclusion, we found that IL-17A induced synergeticrelease of CXCL1 in human vascular endothelial cells with TNF-𝛼. In addition, the synergisticimpact of IL-17A and TNF-𝛼 in terms of CXCL1 induction in vascular endothelial cells wasevident on a transcriptional level. Our data imply that combined blockage of IL-17A and TNF-𝛼 could have an enhanced therapeutic effect on vascular inflammation.
177

Derivation of endothelial colony forming cells from human cord blood and embryonic stem cells

Meador, J. Luke January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Endothelial Colony Forming Cells (ECFCs) are highly proliferative endothelial progenitor cells with clonal proliferative potential and in vivo vessel forming ability. While endothelial cells have been derived from human induced pluripotent stem cells (hiPS) or human embryonic stem cells (hES), they are not highly proliferative and require ectopic expression of a TGFβ inhibitor to restrict plasticity. Neuropilin-1 (NRP-1) has been reported to identify the emergence of endothelial precursor cells from human and mouse ES cells undergoing endothelial differentiation. However, the protocol used in that study was not well defined, used uncharacterized neuronal induction reagents in the culture medium, and failed to fully characterize the endothelial cells derived. We hypothesize that NRP-1 expression is critical for the emergence of stable endothelial cells with ECFC properties from hES cells. We developed a novel serum and feeder free defined endothelial differentiation protocol to induce stable endothelial cells possessing cells with cord blood ECFC-like properties from hES cells. We have shown that Day 12 hES cell-derived endothelial cells express the endothelial markers CD31+ NRP-1+, exhibit high proliferative potential at a single cell level, and display robust in vivo vessel forming ability similar to that of cord blood-derived ECFCs. The efficient production of the ECFCs from hES cells is 6 logs higher with this protocol than any previously published method. These results demonstrate progress towards differentiating ECFC from hES and may provide patients with stable autologous cells capable of repairing injured, dysfunctional, or senescent vasculature if these findings can be repeated with hiPS.

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