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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

Characterizing the role of primary cilia in the hair follicle and skin

Lehman, Jonathan Merle. January 2009 (has links) (PDF)
Thesis (Ph.D.)--University of Alabama at Birmingham, 2009. / Title from PDF title page (viewed on July 14, 2010). Includes bibliographical references.
22

Utilization of gene knockout approaches in the mouse to elucidate additional functions of smad proteins during mammalian development

Hester, Mark 04 August 2005 (has links)
No description available.
23

Influence of the Size and Age of the Ovulatory Follicle on Fertility in Beef Cattle

Mussard, Martin Lane January 2009 (has links)
No description available.
24

The development and atresia of the graafian follicle and the division of intra-ovarian ova in the guinea pig

Kirgis, Homer Dale. January 1937 (has links)
Call number: LD2668 .T4 1937 K51
25

Changes in gene expression during bovine granulosa cell luteinization

Rajapaksha, W. R. A. K. J. S. January 1998 (has links)
No description available.
26

Exploring the role of the phosphatidylinositol-3'-kinase (PI3K) pathway in primordial follicle activation and subsequent development

Spence, Susan Claire January 2016 (has links)
Mammalian females form their germ cells (oocytes) before or shortly after birth. The oocytes interact with somatic cells to form primordial follicles, creating the quiescent population from which oocytes will be recruited to grow throughout life. A female’s fertility life span is therefore, dependant on the size of this pool and the rate at which primordial follicle are activated to grow. However, there is still much we do not know about the quiescent follicle population and the mechanisms that control their recruitment into the growing follicle population are still unclear. There is evidence that the phosphoinositide-3-kinase (PI3K) pathway is key to activation of follicle growth. The role of the PI3K pathway has been primarily explored in the rodent model and has highlighted this pathway’s importance both in the activation of quiescent follicle growth and maintaining dormancy of the quiescent follicle population. This thesis aimed to explore if the PI3K pathway played a similar role in a large mono-ovulatory species as it does in the small polyovulatory rodent species. Bovine is a mono-ovulate species, which has similar attributes in its reproduction and folliculogenesis to the human in vivo; therefore using an in vitro bovine model might be a valuable indication of the role of the PI3K pathway in the human. Initial experiments tested if the bovine was a good model for human primordial follicle activation in an in vitro environment. It was observed that the bovine and human had comparative levels of activation and subsequent increases in both the primary and secondary follicle populations within an in vitro culture system. These similarities indicate that the bovine is a relevant model for the human in vitro. It is not possible to culture the entire bovine ovary. Therefore knowing the location of the primordial follicles is important to establishing what region(s) of the ovary to use. The overall concentration of ovarian follicles was higher in the cortex and gradually declined through the consecutive inner layers of the ovary. The distribution of the ovarian follicle populations were different in each distinctive region of the ovary with the quiescent follicles representing a much larger proportion of the ovarian follicle population in the cortex compared to the inner regions of the ovary. The location an ovarian follicle in the ovary was seen to influence its health in both the quiescent and growing follicle populations, with reduced health seen in the IV inner layers of the ovary compared to the cortex. This resulted in very few healthy quiescent follicles outside of the cortex region making it the more favourable region to culture in functional studies. The role of the PI3K pathway was therefore explored using an in vitro bovine model using the pharmacological compounds bpV (HOpic) and 740Y-P, both of which caused an up-regulation of the PI3K-pathway. It was observed that up-regulation of the PI3K pathway caused an increase in the activation of the quiescent follicle population, and the resulting primary follicles were larger in size. However, there was reduced health in both the growing and quiescent follicle populations. The ill health appears to be due to a disruption in the co-ordination of growth between oocyte and granulosa cells in the ovarian follicles, leading to enlarged oocytes in both the primary follicles and quiescent follicles. Although the PI3K pathway caused an increase in quiescent follicle activation and larger primary follicles there was no increase in the number of viable large secondary follicles obtained. The growth of the secondary follicles was unaltered by the initial activation of the quiescent follicles via the PI3K pathway. These experiments show that the PI3K pathway plays a role in primordial follicle activation in large mono-ovulate species. However, up-regulating the PI3K pathway results in a decrease in health of the quiescent and primary follicle populations, thus limiting its immediate value as a therapeutic target. This study has improved our understanding of the role of the PI3K pathway in primordial follicle activation in a large mono-ovulate species. It has highlighted that the up-regulation of the PI3K pathway using both bpV (HOpic) and 740Y-P increases the activation of the bovine ovarian follicles in vitro. However, up-regulating the PI3K pathway disrupts the development of the ovarian follicles resulting in retarded growth and thereby a decrease in the survival of both the quiescent and growing follicle populations. The similarities in activation, growth and development between the bovine and the human in vitro indicate that the results observed in the bovine are a good indication of what would occur in the human. This study has also improved our understanding of the location, distribution and viability of the ovarian follicle population within the ovary.
27

Cloning of smad proteins in the goldfish and their involvement in activin regulation of FSH[beta] transcription.

January 2003 (has links)
Lau Man Tat. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 95-126). / Abstracts in English and Chinese. / Abstract (in English) --- p.i / Abstract (in Chinese) --- p.iii / Acknowledgements --- p.v / Table of Contents --- p.vi / List of Figures --- p.xi / List of Tables --- p.xiii / Symbols and Abbreviations --- p.xiv / Scientific Names --- p.xvii / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Gonadotropins / Chapter 1.1.1 --- Structure --- p.2 / Chapter 1.1.2 --- Function --- p.6 / Chapter 1.1.3 --- Regulation --- p.9 / Chapter 1.1.3.1 --- Hypothalamic regulators (GnRH) --- p.9 / Chapter 1.1.3.2 --- Endocrine regulators from gonads (steroids) --- p.12 / Chapter 1.1.3.3 --- Paracrine regulators (activin) --- p.14 / Chapter 1.2 --- Activin Family of Growth Factors / Chapter 1.2.1 --- Activin / Chapter 1.2.1.1 --- Structure --- p.14 / Chapter 1.2.1.2 --- Function --- p.14 / Chapter 1.2.1.3 --- Signaling --- p.18 / Chapter 1.2.2 --- Follistatin / Chapter 1.2.2.1 --- Structure --- p.21 / Chapter 1.2.2.2 --- Function --- p.21 / Chapter 1.3 --- Transcriptional regulation of pituitary gonadotropin subunit genes at the promoter level --- p.22 / Chapter 1.4 --- The project objectives and long-term significance --- p.26 / Chapter Chapter 2 --- "Cloning of Smad2, Smad3, Smad4 and Smad7 from the Goldfish Pituitary and Their Involvement in the FSHβ Transcription in LβT2 cells" / Chapter 2.1 --- Introduction --- p.28 / Chapter 2.2 --- Materials and Methods / Chapter 2.2.1 --- Chemicals --- p.31 / Chapter 2.2.2 --- Animals --- p.32 / Chapter 2.2.3 --- Isolation of total RNA --- p.32 / Chapter 2.2.4 --- "Cloning of cDNA fragments of Smad 2, 3, 4 and 7 from the goldfish pituitary" --- p.32 / Chapter 2.2.5 --- Rapid amplification of 5'-cDNA ends (5'-RACE) and full-length cDNA(3'-RACE) --- p.33 / Chapter 2.2.6 --- Primary pituitary cell culture --- p.34 / Chapter 2.2.7 --- "Validation of semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assays for goldfish Smad 2, 3, 4 and7" --- p.35 / Chapter 2.2.8 --- Construction of the reporter plasmid containing the goldfish FSHβ promoter --- p.36 / Chapter 2.2.9 --- Construction of expression plasmids --- p.37 / Chapter 2.2.10 --- Cell culture and transient transfection --- p.38 / Chapter 2.2.11 --- SEAP reporter gene assay --- p.39 / Chapter 2.2.12 --- β-galactosidase reporter gene assay --- p.40 / Chapter 2.2.13 --- Data analysis --- p.40 / Chapter 2.3 --- Results / Chapter 2.3.1 --- "Cloning and sequence characterization of goldfish Smad 2, 3,4 and7" --- p.41 / Chapter 2.3.2 --- "Tissue distribution of Smad 2,3, 4 and 7 expression" --- p.42 / Chapter 2.3.3 --- "Validation of semi-quantitative RT-PCR assays for Smad 2, 3,4 and7" --- p.43 / Chapter 2.3.4 --- Activin regulation of Smad 2,3,4 and 7 expression in cultured goldfish pituitary cells --- p.44 / Chapter 2.3.5 --- "Smad 2, 3 and 7 regulate basal and activin-induced FSHβ transcription in LβT2 cells" --- p.44 / Chapter 2.3.6 --- Autocrine regulation of the gfFSHβ transcription by activin in LβT2 cells --- p.45 / Chapter 2.4. --- Discussion --- p.47 / Chapter Chapter 3 --- Promoter Analysis for the Smad Responsive Element (SRE) in the Goldfish Follicle Stimulating Hormone β(FSHβGene / Chapter 3.1 --- Introduction --- p.71 / Chapter 3.2 --- Materials and Methods / Chapter 3.2.1 --- Chemicals --- p.74 / Chapter 3.2.2 --- Construction of expression plasmids --- p.74 / Chapter 3.2.3 --- Construction of SEAP reporter plasmids containing different lengths of gfFSHβ promoter --- p.74 / Chapter 3.2.4 --- Cell culture and transient transfection --- p.75 / Chapter 3.2.5 --- Reporter gene assays for SEAP and β-Gal --- p.75 / Chapter 3.2.6 --- Data Analyses --- p.76 / Chapter 3.3 --- Results / Chapter 3.3.1 --- Localization of the proximal Smad-responsive Element (SRE) in the gfFHSβ promoter --- p.76 / Chapter 3.4 --- Discussion --- p.78 / Chapter Chapter 4 --- General Discussion / Chapter 4.1 --- Overview --- p.89 / Chapter 4.2 --- Contribution of the present research / Chapter 4.2.1 --- Cloning and characterization of Smad proteins from the goldfish pituitary --- p.90 / Chapter 4.2.2 --- Regulation of Smads in primary pituitary cell culture --- p.90 / Chapter 4.2.3 --- Identification of the Smad responsive element (SRE) on the gfFSHβ promoter --- p.91 / Chapter 4.3 --- Future research direction --- p.93 / References --- p.95
28

Convergent Genesis of an Adult Neural Crest-like Dermal Stem Cell from Distinct Developmental Origins

Jinno, Hiroyuki 22 August 2012 (has links)
Skin-derived precursors (SKPs) are multipotent dermal stem cells that reside within a hair follicle niche and that share properties with embryonic neural crest precursors. Here, we have asked whether SKPs and their endogenous dermal precursors originate from the neural crest or whether, like the dermis itself, they originate from multiple developmental origins. To do this, we used two different mouse Cre lines that allow us to perform lineage tracing: Wnt1-cre, which targets cells deriving from the neural crest, and Myf5-cre, which targets cells of a somite origin. By crossing these Cre lines to reporter mice, we show that the endogenous follicle-associated dermal precursors in the face derive from the neural crest, and those in the dorsal trunk derive from the somites, as do the SKPs they generate. Despite these different developmental origins, SKPs from these two locations are functionally similar, even with regard to their ability to differentiate into Schwann cells, a cell type only thought to be generated from the neural crest. Analysis of global gene expression using microarrays confirmed that facial and dorsal SKPs exhibit a very high degree of similarity, and that they are also very similar to SKPs derived from ventral dermis, which has a lateral plate origin. However, these developmentally distinct SKPs also retain differential expression of a small number of genes that reflect their developmental origins. Thus, an adult neural crest-like dermal precursor can be generated from a non-neural crest origin, a finding with broad implications for the many neuroendocrine cells in the body.
29

Characteristics of subordinate follicles following removal of the dominant follicle induction of selection /

Dean, Matthew January 2009 (has links)
Thesis (M.S.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains vi, 56 p. : ill. Includes abstract. Includes bibliographical references (p. 45-56).
30

Convergent Genesis of an Adult Neural Crest-like Dermal Stem Cell from Distinct Developmental Origins

Jinno, Hiroyuki 22 August 2012 (has links)
Skin-derived precursors (SKPs) are multipotent dermal stem cells that reside within a hair follicle niche and that share properties with embryonic neural crest precursors. Here, we have asked whether SKPs and their endogenous dermal precursors originate from the neural crest or whether, like the dermis itself, they originate from multiple developmental origins. To do this, we used two different mouse Cre lines that allow us to perform lineage tracing: Wnt1-cre, which targets cells deriving from the neural crest, and Myf5-cre, which targets cells of a somite origin. By crossing these Cre lines to reporter mice, we show that the endogenous follicle-associated dermal precursors in the face derive from the neural crest, and those in the dorsal trunk derive from the somites, as do the SKPs they generate. Despite these different developmental origins, SKPs from these two locations are functionally similar, even with regard to their ability to differentiate into Schwann cells, a cell type only thought to be generated from the neural crest. Analysis of global gene expression using microarrays confirmed that facial and dorsal SKPs exhibit a very high degree of similarity, and that they are also very similar to SKPs derived from ventral dermis, which has a lateral plate origin. However, these developmentally distinct SKPs also retain differential expression of a small number of genes that reflect their developmental origins. Thus, an adult neural crest-like dermal precursor can be generated from a non-neural crest origin, a finding with broad implications for the many neuroendocrine cells in the body.

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