5 research outputs found

    Regulators of growth plate maturation

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    Estrogen is known to play an important role in longitudinal bone growth and growth plate maturation, but the mechanism by which estrogens exert their effect is not fully understood. In this thesis this role is further explored. Chapter 1 contains a general introduction to longitudinal bone growth and the regulation of the growth plate in respect to relevant topics further studied in this thesis. Estrogen can act through a genomic or a nongenomic pathway. Both pathways are explored in rats at the onset of maturation in chapter 2. Estrogen stimulates VEGF expression in uterus and bone, which is an important growth factor for chondrocyte differentiation and chondrocytes survival in the growth plate. In chapter 3 the effect of estrogen on VEGF expression in the growth plate was studied in the rat and human growth plate. Another effect of estrogen is that it accelerates growth plate senescence. Senescence is one of the postulated intrinsic mechanisms by which the growth plate matures and finally fuses. In chapter 4 we investigated senescence in relation to proliferation, by investigating a cell cycle inhibitor p27Kip1. In animal models, catch-up growth is suggested to be caused by delayed growth plate senescence. In chapter 5 this hypothesis was further tested in humans. With puberty estrogen levels increase, the growth plate matures and at the end growth ceases with epiphyseal fusion through mechanisms not yet completely understood. In order to further explore growth plate maturation we subjected two growth plate tissues of the same patient, but with one year and one pubertal Tanner stage in between, to microarray analyses. Gene expression patterns and transcription factor binding sides in relation to pubertal maturation were studied in a longitudinal study within this single patient in chapter 6. In addition, we collected extra prepubertal and pubertal growth plate tissues and studied these samples with microarray techniques as well in chapter 7. In chapter 8 the process of epiphyseal fusion and apoptosis was studied in human growth plates. Animal models are frequently used but not fully representative for the human growth plate. Therefore we investigated a promising human in vitro model with multipotent mesenchymal stem cells (MSCs) that can differentiate into chondrocytes. MSCs can be isolated from various tissues. In chapter 9 we investigated the chondrogenic potential of MSCs from different origins and in chapter 10 we compared this model with the epiphyseal growth plate by analyzing gene expression patterns and pathways with micro-array analyses. Chapter 11 contains general conclusions and a discussion regarding the results.Afdeling kindergeneeskunde, Jurriaanse stichting, NVCB, Ipsen, Novo Nordisk, Greiner Bio-One, Ferring BV, Eli Lilly, Pfizer, NutriciaUBL - phd migration 201

    Regulators of growth plate maturation

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    Estrogen is known to play an important role in longitudinal bone growth and growth plate maturation, but the mechanism by which estrogens exert their effect is not fully understood. In this thesis this role is further explored. Chapter 1 contains a general introduction to longitudinal bone growth and the regulation of the growth plate in respect to relevant topics further studied in this thesis. Estrogen can act through a genomic or a nongenomic pathway. Both pathways are explored in rats at the onset of maturation in chapter 2. Estrogen stimulates VEGF expression in uterus and bone, which is an important growth factor for chondrocyte differentiation and chondrocytes survival in the growth plate. In chapter 3 the effect of estrogen on VEGF expression in the growth plate was studied in the rat and human growth plate. Another effect of estrogen is that it accelerates growth plate senescence. Senescence is one of the postulated intrinsic mechanisms by which the growth plate matures and finally fuses. In chapter 4 we investigated senescence in relation to proliferation, by investigating a cell cycle inhibitor p27Kip1. In animal models, catch-up growth is suggested to be caused by delayed growth plate senescence. In chapter 5 this hypothesis was further tested in humans. With puberty estrogen levels increase, the growth plate matures and at the end growth ceases with epiphyseal fusion through mechanisms not yet completely understood. In order to further explore growth plate maturation we subjected two growth plate tissues of the same patient, but with one year and one pubertal Tanner stage in between, to microarray analyses. Gene expression patterns and transcription factor binding sides in relation to pubertal maturation were studied in a longitudinal study within this single patient in chapter 6. In addition, we collected extra prepubertal and pubertal growth plate tissues and studied these samples with microarray techniques as well in chapter 7. In chapter 8 the process of epiphyseal fusion and apoptosis was studied in human growth plates. Animal models are frequently used but not fully representative for the human growth plate. Therefore we investigated a promising human in vitro model with multipotent mesenchymal stem cells (MSCs) that can differentiate into chondrocytes. MSCs can be isolated from various tissues. In chapter 9 we investigated the chondrogenic potential of MSCs from different origins and in chapter 10 we compared this model with the epiphyseal growth plate by analyzing gene expression patterns and pathways with micro-array analyses. Chapter 11 contains general conclusions and a discussion regarding the results

    Peanut components measured by ISAC

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    Background: Specific IgE (sIgE) against the peanut component Arachis hypogaea (Ara h) 2 has been shown to be the most important allergen to discriminate between peanut allergy and peanut tolerance. Several studies determined sIgE cut off values for Ara h 2, determined by singleplex measurements. However, cut off values for Ara h 2 from multiplex arrays are less well defined. The aim of this study was to evaluate the correlation between Ara h 2 sIgE determined by singleplex versus multiplex measurements and to assess the diagnostic value of the different peanut components included in Immuno Solid-phase Allergen Chip (IS

    Caracterització dialectal del Diccionari Aguiló. A partir de les dades de Menorca, Eivissa i Formentera

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    Treballs Finals de Grau de Filologia Catalana, Facultat de Filologia, Universitat de Barcelona, Curs: 2013-2014, Tutores: Neus Nogué i Maria-Pilar PereaL'obra lexicogràfica de Marià Aguiló és catalogada pels estudiosos com un aplec de materials de la llengua antiga, complementats de manera secundària amb aportacions dialectològiques i onomàstiques. Si bé és cert que quantitativament el cabal d'informació referent a la llengua antiga té un paper predominant al llarg de l'obra, cal no bandejar la importància de la resta de les dades que brinda. En aquest estudi es farà una aproximació al caràcter dialectològic dels materials d'Aguiló, de manera que es prescindirà de la informació històrica, toponímica i antroponímica. El fet que sigui una obra poc estudiada amb valor dialectològic poc conegut, fa necessari un estudi que ajudi a tenir una visió global del Diccionari Aguiló (DA) en aquest camp per poder desmuntar, si cal, alguns prejudicis. Una anàlisi completa de l'obra partint de totes les referències dialectals hauria excedit les dimensions d'aquest estudi, per la qual cosa s'han escollit unes àrees determinades a manera de referència. Malgrat les precaucions necessàries a l'hora d'extrapolar-ne els resultats, una anàlisi d'aquestes característiques ja pot oferir una primera aproximació a l'obra i orientar l'usuari del diccionari en la seva recerca
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