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1
Dean, Matthew. "Characteristics of subordinate follicles following removal of the dominant follicle induction of selection /". Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10696.
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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).
2
Philpot, Michael Paul. "Studies on isolated hair follicles". Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253402.
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3
Miranda, Benjamin H. "Development of a novel, clinically-relevant model for investigating factors that stimulate human hair growth". Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5731.
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Lack of hair due to alopecia or skin grafting procedures causes significant distress due to hair's role in social and sexual communication. Only limited pharmacological agents are currently available to stimulate hair growth; their development is hampered by inappropriate model systems. Most research involves large terminal scalp follicles rather than the clinical targets of tiny vellus or intermediate follicles. The overall aim of this thesis was to develop a novel model system based on intermediate hair follicles. Initially, intermediate follicles from female pre-auricular skin were characterised and compared to matched terminal follicles. Intermediate follicles were smaller, less pigmented, shorter and possessed a more 'tubular' bulb morphology than their more 'bulbous' terminal counterparts. Significant correlations were demonstrated between various hair follicle measurements and corresponding dermal papilla diameters. Isolated terminal follicles grew significantly more than intermediate hair follicles in organ culture for 9 days. Testosterone (10nM), the major regulator of human hair growth, increased only intermediate follicle growth; the anti-androgen, cyproterone acetate (1μM), prevented this stimulation, unlike the 5α-reductase type 2 inhibitor finasteride (40ng/ml). Immunohistochemistry demonstrated androgen receptor and 5α-reductase type 2 proteins in both follicle types, while quantitative real-time PCR and gene microarray analysis detected their increased gene expression in intermediate follicles. Thus, smaller intermediate follicles showed major morphological and gene expression differences to terminal follicles in vivo and retained significant, biologically-relevant differences in vitro in organ culture including androgen-responsiveness. Therefore, intermediate hair follicles offer a novel, exciting, more clinically relevant, albeit technically difficult, model for future investigations into hair growth.
4
Dubbaka, Venu Pradeep Reddy. "Molecular studies of intra-oocyte phosphatidylinositol 3 kinase (PI3K) signaling pathway in controlling female fertility". Doctoral thesis, Umeå : Umeå university, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-26088.
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5
Bark, Monica Clare. "Development of porcine preantral follicles in vitro". Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/10731.
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The development of a culture system to sustain preantral follicle growth to a stage where fertilisable oocytes can be obtained remains elusive in the domestic species. The objectives of this thesis were to develop a culture system capable of supporting porcine preantral follicles, and identify possible markers of oocyte and follicle development. Follicles were cultured in two systems; individually in McCoys medium to identify the effects of ascorbic acid, FSH, and serum, and in NCSU medium individually (96-well plates) or in-groups (24-well plates) to identify the effects of follicle interactions. Results from the McCoys experiment revealed that somatic cell death was significantly reduced in follicles cultured in the presence of ascorbic acid in comparison with other treatment groups, but the vitamin was found to have no effect on follicle growth. Follicle growth was significantly enhanced by the addition of serum and FSH to serum-free medium, but FSH had no effect as a survival factor on granulosa cell death in follicles. Culture in NCSU medium revealed that follicles grew best when cultured individually in the presence of serum in 96-well plates in comparison to follicles cultured in-groups in 24-well plates. All other parameters of follicle health and development were found to be no different between follicles cultured in serum in-groups of individually. The identification of markers of development for follicles and oocytes could also aid the development of a culture system for preantral follicles. GDF-9 is a possible indicator of follicle and oocyte developmental stage. It has been identified in several species, including human, rodents, and domestic species, but not in the pig. In this study it was isolated using human and mouse primers, and sequenced. It was found to display 88% homology to the human sequence. RT-PCR revealed that it appears to be expressed strongly in the porcine oocyte, but not in granulosa, skin or intestinal cells. BMP-15 was also found to be oocyte-specific in the pig, using sheep primers to identify its location.
6
Starr, Perry Louise. "The effects of cryopreservation on human ovarian follicles". Thesis, University of Warwick, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441573.
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7
Yang, Ming Yuan. "Studies on apoptosis in bovine follicles and embryos". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0019/NQ56648.pdf.
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8
McCaffery, Fiona Helen. "The development of bovine preantral follicles in vitro". Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/15317.
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Satisfactory development of preantral follicles from humans and domestic ruminants in vitro remains elusive. The aims of this thesis were to use a serum-free culture system to identify regulators of early follicle and oocyte development. Preliminary experiments determined that bovine preantral follicles grow and produce increasing amounts of oestradiol throughout a six day culture period. Neither FSH nor IGF-1 significantly increased follicle diameter. However, FSH did promote follicular oestradiol secretion. The dissociation of follicular growth from steroidogenenic function indicated that measurement of follicular diameter may not be a reliable marker of physiological follicular development in vitro. In addition, stimulation of granulosa cells by FSH may result in inappropriate differentiation of these cells during the early stages of folliculogenesis. During follicular development, turnover and reconstruction of the basement membrane is facilitated and regulated by matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). When MMP-9 was secreted by prenatal follicles in vitro, the probability of follicles having healthy granulosa or theca cells at the end of culture was 0.85 and 0.60, respectively. If TMP-1 was released, there was a probability of 0.79 that the follicles would have healthy somatic cells. When TIMP-2 was detected, the probability of granulosa and theca cell health was 0.78 and 0.67, respectively. These results indicate that MMP-9 and TIMPs are related to follicular health, and can therefore be used as markers of follicular development. Ascorbic acid has been implicated in several processes associated with follicular development, including collagen biosynthesis, steroidogenesis and apoptosis. The effect of this vitamin on the development of bovine preantral follicles was investigated during a twelve day culture period. Ascorbic acid had no effect of follicular growth or oestradiol secretion. Serum addition from Day 0 stimulated follicular growth but compromised follicular integrity. By Day 12 of culture, a higher proportion of follicles remained intact in the presence of ascorbic acid in serum-free conditions, with significantly less granulosa and theca cell death than control follicles.
9
Torrance, Colin. "Aspects of the developmental biology of ovarian follicles". Thesis, University of Edinburgh, 1991. http://hdl.handle.net/1842/20251.
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Ovarian follicles are recruited from a pool of nongrowing primordial follicles and progress slowly through early phases of growth until the formation of an antrum. Little is known at present about the factors controlling follicle recruitment, preantral growth, or thecal and antral formation. This thesis reviews some aspects of early folliculogenesis and describes the development of a culture system for in vitro investigation of preantral growth. A enzymatic-mechanical isolation procedure was developed which permitted large numbers of isolated small ovarian follicle to be obtained for CBA/C57B16 hybrid mice, aged 8-10 days. The ovarian follicle is a spherical structure containing initially two main cell types - oocyte, granulosa cells with the thecal cell differentiating once the follicle has entered its growth phase. Interactions between these cell types may have an important role in controlling folliculogenesis and cell shape, cell-cell interactions and cell-extracellular matrix interactions may all influence follicular growth. To support and maintain cell shape and the spatial relationships between the cells types in the ovarian follicle a culture system involving embedding the follicles within a three-dimensional collagen gel matrix was developed. A quantitative study of isolated murine follicle growth in collagen gel culture over two weeks was carried out. The system facilitated follicle growth from small to multilaminar stages but antral formation and theca differentiation was not initiated. Cultured follicles were transferred under the kidney capsule of ovariectomized host. In vivo the follicle were able to progress to the Graafian stage. The effects of hormones and growth factors (oestrogen, follicle stimulating hormone and epidermal growth factor) on in vitro follicle development were studied using autoradiography and computer assisted image analysis.
10
Nattrass, Gregory Scott. "Molecular and functional characterisation of a system ASC-like neutral amino acid transporter expressed in the wool follicle /". Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09ANP/09anpn284.pdf.
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11
Rothnagel, Joseph Attila. "Biochemical studies on trichohyalin : the origin of the citrulline-containing proteins in the hair follicle /". Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phr846.pdf.
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12
Ansell, David. "The role of hair follicles in cutaneous wound healing". Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/the-role-of-hair-follicles-in-cutaneous-wound-healing(b8fbd6aa-f43f-4579-9a54-b2e4c4705cdb).html.
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Over the past decade the concept that the hair follicle plays an important role in cutaneous wound repair has been established. Several elegant lineage tracing studies have demonstrated that hair follicle derived cells contribute to the long term maintenance of the epidermis following repair, while an absence of hair follicles is known to delay repair. The exact mechanisms surrounding hair follicle derived repair are unknown. Moreover, while multiple stem cell niches are present within the hair follicle, their relative importance during wound repair is still unclear. The hair follicle is also a regenerative mini-organ, undergoing regular cycles of growth and regression throughout life, yet surprisingly this has not been previously investigated with respect to wound repair. Data presented in this thesis reveals an unappreciated, yet fundamental link between the independent processes of hair cycle and wound repair, with a substantial acceleration in the rate of repair (~50%) observed in anagen phase. Importantly, the hair follicle appears to play a global role in repair, with differences in the contribution of multiple cell types to wound repair. In addition, this thesis addresses the early kinetics of hair follicle wound response for the first time. Anagen hair follicles are found predisposed to a more rapid and extensive response to injury, suggesting a higher overall percentage of repair derived from the hair follicle in anagen phase. Surprisingly, the bulge stem cell region, while critical for hair cycle appears to play little role in the events immediately following injury, and is not required for initiation of re-epithelialisation. Gene expression profiling reveals numerous genes associated with anagen accelerated repair, and identifies altered modulation of the immune system as a key mechanism. Further, anagen wounds are associated with an upregulation of developmental transcription factors, which may imply a more regenerative healing phenotype. These data reveal numerous targets with the potential to accelerate repair, which now require validation for their therapeutic potential. These targets could be of importance in promoting the repair of chronic wounds, an area of unmet clinical need. More generally, this thesis has established hair cycle as an important experimental variable, which must be controlled for in all future in vivo murine wounding studies.
13
Nishikawa(Torikai), Satomi. "Functional characterization of melanocyte stem cells in hair follicles". Kyoto University, 2011. http://hdl.handle.net/2433/151927.
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14
Fietz, Michael James. "Purification and analysis of the trichohyalin gene : an examination of the role of tricohyalin in the inner root sheath /". Title page, contents and summary only, 1991. http://web4.library.adelaide.edu.au/theses/09PH/09phf468.pdf.
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15
Quennell, Janette Henrietta, e n/a. "Molecular and cellular biology of FGF2 in human ovarian follicles". University of Otago. Department of Anatomy & Structural Biology, 2006. http://adt.otago.ac.nz./public/adt-NZDU20061025.142115.
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Ovaries maintain and produce functional female gametes, oocytes, for fertilisation. Oocytes develop inside cellular assemblies, the ovarian follicles, before birth and can reside there for up to 50 years in the human. Despite recent inroads, the precise mechanisms of initial follicle recruitment and growth remain unclear. Although the pituitary gonadotrophins play a role in this developmental process, locally produced factors have been implicated strongly in initiation of follicle growth. It is known that fibroblast growth factor 2 (FGF2) is a powerful mitogen for follicular granulosa cells in culture and initial studies undertaken in this project were successful in detecting FGF2 gene expression in ovarian biopsies from fertile healthy women. To further elucidate which cells were expressing FGF2, laser microdissection was employed to isolate differentially staged follicle populations. Real-time RT-PCR was used to quantify mRNA in relation to follicle development. Decreasing levels of FGF2 expression were detected as follicles developed. Non-radioactive in situ hybridisation confirmed FGF2 mRNA localisation in granulosa cells of preantral follicles. FGF2 protein localisation was assessed with immunohistochemistry; two primary antibodies raised against different fragments of human FGF2 were used. Both antibodies detected FGF2 in the oocyte cytoplasm of putative non-growing follicles, whereas only one of the antibodies showed additional reactivity to the basement membrane region of these same follicles. These results suggest different isoforms of FGF2 may localise specifically to different cellular sites.
Follicle stimulating hormone receptor (FSHR) gene expression was also investigated in follicles using laser microdissection, real-time RT-PCR and in situ hybridisation. FSHR mRNA was detected in all follicle populations, including the smallest putative non-growing follicles. Disparity to other published works was attributed to the position of primer annealing, and thus the ability to detect alternatively spliced transcripts.
In conclusion, the work presented here provides evidence that FGF2 and FSHR are present in small follicles and that their actions may be stimulatory or inhibitory to initial follicle recruitment.
16
Wen, Xue Song. "Cytokines and metabolic profiling from pre-ovulatory luteinsed human follicles". Thesis, Queen Mary, University of London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427992.
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17
Frum, Yakov. "Percutaneous drug delivery and the role of follicles and defects". Thesis, University of Strathclyde, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501822.
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In this study, diverse in vitro studies were undertaken in order to examine the influence of hair follicles and intrinsic skin structure heterogeneities on transdermal drug delivery. The skin sandwich system was used to investigate the influence of drug partition coefficient on follicular delivery in each of human and porcine skin. To this end, eight different drugs (estradiol, corticosterone, hydrocortisone, aldosterone. cinictidinc, dcoxyadcnosine, adenosine and sucrose) exhibiting a wide range of log ocianol-water partition coefficients but comparable molecular weights were selected. In both skin species, a plot of percentage follicular contribution as a function of solute log octanol-watcr partition coefficient yielded a parabolic relationship.
18
Muruvi, Wanzirai. "'In vitro' development of early-stage ovarian follicles in sheep". Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414245.
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19
Atkinson, S. "The characterisation of induced ovarian follicles in seasonally anoestrous ewes". Thesis, Atkinson, S. (1985) The characterisation of induced ovarian follicles in seasonally anoestrous ewes. PhD thesis, Murdoch University, 1985. https://researchrepository.murdoch.edu.au/id/eprint/53361/.
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The overall objectives of this project were to characterise the effect of· two known stimuli of the reproductive system on ovarian activity in seasonally anoestrous ewes, and to determine the hormonal patterns that accompany ovarian changes through the transition from seasonal quiescence to follicular activity.
To characterise the ovarian and hormonal changes that occur, measurements were made of: (1) the concentrations of circulating gonadotropins, (2) the concentration of oestradiol from the ovarian venous effluent, ( 3) the recruitment (antrum formation), growth and maturation of ovarian follicles, (4) the steroid production from the induced follicles and (5) the presence of gonadotropin receptors in the granulosa cell layer of the follicles; through this transition...
20
Blackwell, Lorna Evelyn. "In vitro growth and development of ovarian follicles for fertility preservation". Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7435/.
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A physiological culture system that supports the in vitro growth (IVG) and development of oocytes would be an invaluable tool for the development and optimisation of fertility preservation techniques. Markers of oocyte, follicle and ovarian stromal tissue normality need to be established to ensure in vitro-derived oocytes are healthy and developmentally competent. A 2-step, physiological IVG system was developed that supported (1) activation, growth and development of ovine primordial follicles in situ over 16-23 days; yielding 37 secondary follicles over 31 repeat cultures and (2) development of in vivo- (n=85) and in vitro-derived secondary follicles to the early antral stage, 25% and 19%, respectively. Step (1) was compared to an accelerated system (n=24), which, unlike the physiological system, resulted in a significant increase (p<0.05) in the proportion of degenerating follicles and decrease (p<0.05) in stromal tissue integrity following 6 days culture compared to day 0 control tissue. In addition a significantly higher yield of transitional (p<0.01) and secondary (p<0.05) follicles resulted from the physiological vs. the accelerated system. The expression patterns of 20 genes key to oogenesis and folliculogenesis were established in vivo and compared to stage-matched samples derived using the physiological IVG system, revealing significant changes (p<0.05) in the expression of AMH, IGF1, INHα, INHβA, FST, ZP2, GTSF1, BMP6, BMP15 and MEST. Step (1) was used to evaluate damage to oocyte and ovarian tissue health following the perfusion of 48 ovaries, with either 1.5M dimethyl sulphoxide (DMSO) or L-15 control medium, in combination with the use of NMR spectroscopy to determine the level of DMSO permeation. Perfusion times of 10 and 60 minutes were required permeate the pedicle and cortex tissue, respectively, however, 60 minutes perfusion resulted in a significant decrease in follicle number (p<0.01) and stromal tissue integrity (p<0.05). The overall results indicate that the IVG of oocytes is a suitable tool to both assess the patency of fertility preservation systems and as a means to restore female fertility.
21
Zhang, Pu. "Human ovarian follicles and oocytes : collection, cryopreservation, culture and gene expression /". Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-281-0/.
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22
Cotterill, Matthew. "Gene function during the development of ovine oocytes and ovarian follicles". Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496543.
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Gadd, Stephanie Clare. "Insulin-like growth factor II in preovulatory follicles and ovarian cysts". Thesis, University of Southampton, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296517.
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McLaughlin, Marie. "Factors affecting in vitro development of bovine and human ovarian follicles". Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/15350.
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Kirk, Laura I. "Niosome and Microparticle Encapsulation of Antimicrobial Agents for Targeting Hair Follicles". University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1227204968.
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26
Telfer, Evelyn Elizabeth. "Factors influencing follicular development in mammalian ovaries". Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/26993.
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The studies described in this thesis have been concerned with several aspects of follicular development in the mammalian ovary. Chapters 2, 3 6 4 deal with mathematical modelling of ovarian follicle dynamics in normal animals and comparisons with experimentally manipulated animals. Chapter 5 describes a novel aethod for estimating the clonal origin of the mouse ovarian follicle. In the final two chapters, the comparative physiology and anatomy of follicular numbers and sizes and the incidence of polyovular follicles are described for a number of species. The unifying theme of these studies is that they reveal patterns existing in follicular development and utllisation by detailed examination of one species, (CBA/ca mouse), and broadly by interspeci,fic comparisons (with relation to scaling). A detailed mathematical description of the follicular dynamics of virgin CBA/ca mice up to 98 days of age has been obtained by the application of compartmental modelling to differential follicle counts. The rates of follicle growth (migration) and death have been estimated for five ?stages of development (primordial to Graafian). The model predicts age changes in follicle growth and death rate, there being transitions in the parameters at 20 days second at 60 days. The parameters for normal animals have been compared with those of anilllals under two experimental conditions: 1) by unilateral ovariectomy at 4-2 days of age, which abruptly halves the numbers of ovarian follicles and alters the ratio of large : small follicles. 2) by blocking ovulation using progesterone implants. The dynamics of follicle growth were altered by both treatments in comparison with the controls. Follicles at all stages of development were affected by unilateral ovariectomy and differences may exist with time. The compensatory response by the remaining ovary was due to a combination of an increased preantral growth rate and a decrease in atresia at antral stages. Earlier stages of follicle development were affected this may have been incidental to the compensatory response. In progesterone treated animals follicles developed through to antral stages when they un~erwent atresia. The effects of treatment were observed at three levels of development: 1) The initiation of growth from the primordial pool, 2) Growth rate of small follicles and 3) deaths at larger stages of follicular development. Longer term observations indicated that these effects may not be constant. The modelling studies have looked at numerical changes in the follicle population with time but a greater understanding of the develomental biology of the follicle is required in order to explain the changes in growth and death rates observed. This problem has been tackled initially by studying the clonal origin of the follicular epithelium. The technique used is based on the principle that cells in females. are generally mosaic as a result of X-chromosome inactivation the use of X linked cell markers phospho-glycerate kinase-1 (PGK-1). Granulosa cells were found to be polyclonal in origin with the number of progenitor cells numbering 5 on average. Analysis of cumulus and mural granulosa cells showed that substantial cell mixing had occurred and cuaulus cells were generally founded by more than one clone. Finally, comparative studies have been conducted to look at scaling of follicle sizes and numbers and of polyovular follicles. Ovarian follicle and oocyte sizes were scaled according to body weight (ranging from .005-500Kg) using data from 22 species. Primordial and Graafian follicle sizes varied with body weight but closer correlations for the latter were obtained when the sum of the surface areas or volUiles for a preovulatory set were considered as opposed to the values for individual follicles. The numbers of nongrowtng follicles 1n reserve at young adult ages were correlated with maximum longevity of the species and related to body weight. The frequency of polyov~lar follicles varied 1n species studied and were most abundant 1n the domestic bitch. The overall incidence of polyovular folUcles 1n young bitches was 14 S, being reduced to 5~ 1n bitches at 7-11 years. The frequency of the various types of polyovular preantral folUcle varied inversely with the numbers of oocytes per follicle.
27
Boerboom, Derek. "Gene regulation of prostaglandin and steroid hormone biosynthesis in equine preovulatory follicles". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/NQ55454.pdf.
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Garcin, Clare. "The role of hair follicles and Edar signalling in cutaneous wound healing". Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/the-role-of-hair-follicles-and-edar-signalling-in-cutaneous-wound-healing(d39d35be-91e6-4b46-b1be-f91b60581145).html.
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The Ectodysplasin/Ectodysplasin receptor (Eda/Edar) signalling pathway is critical during development for the formation of skin appendages. However, its roles during adulthood are only recently being elucidated. Adult appendages, such as hair follicles (HFs), are known to become activated to respond to cutaneous injury. However, the HF houses distinct cell populations that display differing capacities to participate and persist in re-epithelialisation. We show, contrary to previous findings, that the best-characterised stem cell (SC) niche within the HF (the bulge) does not respond to injury during the earliest stages of wound healing. We propose that bulge SCs are prevented from participating in early repair as a protection mechanism against tumourigenesis. Despite the bulge niche not participating in early repair, we found the upper HF outer root sheath (ORS) to respond rapidly to injury. Our investigation into the role of Eda/Edar signalling during wound healing revealed that activation of the pathway was able to specifically induce proliferation within this portion of the HF. We further demonstrate a number of roles for the Eda/Edar pathway during adult wound healing, including, surprisingly, influencing several wound responses within the dermis. Specifically, an absence of Eda/Edar signalling in Tabby mice results in delayed wound healing, whereas acute activation of the pathway in wild-type (WT) mice can stimulate re-epithelialisation and enhance wound repair. These effects also translate to a model of human wound healing, where activation of Eda/Edar signalling accelerates re-epithelialisation and increases peri-wound proliferation. RNA-seq analysis reveals diverse gene regulation in the presence/absence of Eda/Edar signalling. Overall, these findings suggest that manipulation of the Eda/Edar pathway may represent an attractive potential therapeutic for enhancement of wound repair, potentially through maximising the natural growth capacity of peri-wound HFs.
29
Faber, Eric G. "Follicular dynamics, estradiol-17[beta] concentrations, and luteinizing hormone release following norgestomet implant insertion during estrus synchronization with melengestrol acetate". Thesis, Virginia Tech, 1995. http://hdl.handle.net/10919/45059.
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The objective of this experiment was to determine whether norgestomet implant insertion following melengestrol acetate (MGA) administration altered LH pulse frequency and follicular dynamics. Multiparous Angus cows were randomly assigned to receive MGA (.5 mg*cow-l*d-l ; MGA; n = 14) for 18 d or to receive MGA (.5 mg*cow·-l l*d-l; MGA-N; n = 11) for 15 d and a norgestomet implant for 4 d beginning on d 15. Ultrasound was used to record images of each ovary in cows beginning on d 8 of MGA administration. On d 16, serial blood samples were collected from all cows in replicate one (MGA, n=6; MGA-N, n=6) for quantification ofLH pulse frequency. A persistent, dominant follicle was identified in all cows on d 8 ofMGA administration. Forty-three percent and 64% (P > .10) of MGA and MGA-N cows, respectively, initiated a new wave of follicular development during treatment that was the source of the ovulatory follicle. Pulse frequency of LH did not differ between MGA and MGA-N cows or between cows that ovulated a persistent (PERSIST) follicle and those that ovulated a follicle from a new follicular wave (NEW). Growth rate of the ovulatory follicle for the 7 d preceding ovulation was greater in PERSIST than in NEW cows (P < .01). Diameter of the owlatory follicle on the day preceding ovulation was greater in PERSIST cows than in NEW cows (P < .01). In conclusion, MGA administration caused a persistent follicle to develop, but that follicle was unable to be regressed consistently by supplemental norgestomet administration.
Master of Science
30
Liu, Jianmin. "Molecular control of prostaglandin G/H synthase-2 expression in bovine preovulatory follicles". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ43729.pdf.
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OSIR, ELLIE ONYANGO. "VITELLOGENIN OF THE TOBACCO HORNWORM, MANDUCA SEXTA: PROPERTIES AND ENDOCYTOTIC INCORPORATION INTO FOLLICLES". Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/188160.
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Manduca sexta vitellogenin is a phosphoglycolipoprotein (Mᵣ ∼ 500,000) that contains two copies of the apoproteins (apovitellogenin-I, Mᵣ 180,000 and apovitellogenin-II Mᵣ 45,000), 13 percent lipids, 3 percent carbohydrates and 0.6 percent phosphorus. The two apoproteins are immunologically distinct and apovitellogenin-II is not completely accessible to the aqueous environment in the intact molecule. The carbohydrate moiety located on apovitellogenin-I has a high mannose structure (Man₉ GlcNAc₂). Follicle membranes bind ¹²⁵I-labeled vitellogenin with high affinity and specificity (K(D) ≃ 1.3 x 10⁻⁸ M). Total binding sites were estimated at 4 x 10¹⁴ sites/g of follicle membrane protein. The binding was sensitive to pH and calcium. Competition studies showed that binding of vitellogenin was blocked by vitellin and deglycosylated vitellogenin but not by lipophorin, microvitellogenin or apovitellogenin-II. These results suggest that the uptake of vitellogenin involves binding to specific receptors on follicle membranes and the carbohydrate moiety and apovitellogenin-II are not involved in the interaction with the receptors.
32
Pryor, Andrew William. "Reproduction and Endocrine Aspects of Early and Mid Lactation Holstein Cows". Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/32486.
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This study was designed to determine the effects of stage of lactation and subsequent energy status on metabolic and endocrine measures, follicular development, and the quality of oocytes obtained from Holstein cows. Holstein cows were selected prior to calving and assigned to the early lactation (EL) group (n=8) while, cows at d 90 postpartum were selected for the mid-lactation (ML) group (n=7). Blood samples were taken twice weekly from 4 wk prior to the start of follicular aspirations and then on through the aspiration periods for metabolite and hormone determination. Ultrasound-guided transvaginal follicular aspiration (TVFA) was conducted twice weekly for a 10-wk period on all cows. Follicular fluid samples were obtained from the largest follicle, > 10 mm in diameter, for hormone determination. All data were analyzed by ANOVA, using the general linear model procedures. Mean energy balance was positive for (2.43 ± 0.32 Mcal/kg) for ML cows and negative (-1.55 ± 0.33 Mcal/kg) for EL cows. In ML cows serum progesterone (P4) decreased rapidly from 2.7 ± 0.1 ng/ml at the first aspiration session to a nadir of 0.33 ± 0.1 ng/ml at wk 8, while follicular fluid P4 increased from 0.9 ± 0.5 to 5.6 ± 0.5 ng/ml. In the EL cows serum and follicular fluid P4 remained relatively constant over the course of aspirations. There was a linear increase in follicular fluid insulin-like growth factor I (IGF-I) for EL and ML cows, however the increase was more rapid for ML cows (159 ± 36 to 200 ± 36 ng/ml) than for EL cows (145 ± 36 to 164 ± 36 ng/ml). Over the aspiration period nonesterified fatty acids (NEFA) declined rapidly for the EL cows (0.32 ± 0.2 to 0.22 ± 0.2 mEq/L), while serum NEFA for the ML cows were relatively stable (0.19 ± 0.2 to 0.22 ± 0.2 mEq/L). The number of follicles observed during the aspiration sessions increased linearly for both EL and ML cows (P < 0.05) over the 10-wk period. However, the increase was larger for the ML cows than for the EL cows, going from 14.2 ± 0.5 to 18.1 ± 0.5 and 14.9 ± 0.3 to 15.7 ± 0.5, respectively. These results show that cows in early lactation are physiologically under more production stress than cows in mid lactation. Furthermore, increasing levels of serum and follicular fluid IGF-I in mid lactation may reflect differences in follicle and oocyte measures.Master of Science
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Hodovanic, Kelly. "Effects of retinoic acid on wingless (WNT) signaling in the hair follicles of mice". Connect to resource, 2010. http://hdl.handle.net/1811/45456.
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Yang, Chia-Ling. "Studies on the metabolism, ageing and response to epidermal growth factor of hair follicles". Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620083.
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Zampolla, Tiziana. "Development of new methods to assess the quality of zebrafish (Danio rerio) ovarian follicles". Thesis, University of Bedfordshire, 2009. http://hdl.handle.net/10547/134961.
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High quality fish oocytes are essential for in vitro maturation (IVM), in vitro fertilization (IVF) protocols, and for use in cryopreservation. It is important to develop methods for assessing oocyte quality for applications in aquaculture, the preservation of endangered species and managing fish models used in biomedical research. The lack of reliable methods of evaluating oocyte quality limits progress in these areas. The present study was undertaken to develop new methods to assess ovarian follicle viability and quality of stage III zebrafish (Danio rerio) ovarian follicles. The methods developed were then applied to study the impact of cryoprotectant and/or cryopreservation procedures. A vital staining procedure, not previously used with zebrafish oocytes, has been investigated. FDA-PI (Fluorescein diacetate-Propidium Iodide) staining was found to be a more sensitive then currently used viability tests and it could also be applied to all ovarian follicles developmental stages. Mitochondrial activity and distribution as biological markers was investigated with the mitochondrial membrane potentialsensitive dye JC-1- (5,5’,6,6’-tetrachloro-1,1’,3,3’-tetraethylbenzimidazolylcarbocyanine iodide). Confocal microscopy, Cryo-scanning and electron microscopy studies were undertaken to determine mitochondria distributional arrangement within the ovarian follicle. This provided new information on zebrafish ovarian follicle structure, and showed that mitochondria exhibited a contiguous distribution at the margin of the granulosa cell layer surrounding stage III zebrafish oocytes. Cryoscanning results showed a polygonal structure of the vitelline envelope, which is reported here for the first time with the mitochondrial distributional arrangement in the granulosa cell layer. Mitochondrial distribution and the evaluation of mitochondrial activity proved to be sensitive markers for ovarian follicle quality, providing more detailed information on cryoprotectant impact. The measurement of ATP levels, ADP/ATP ratio and mtDNA copy number were also undertaken following cryoprotectant exposure. These findings, together with the observation of mitochondrial distribution, suggested that even cryoprotectant treatments that are considered to have little or no toxicity can have a deleterious effect on mitochondrial activity, potentially compromising oocyte growth and embryo development. Therefore, a further optimization of the currently used protocol may need to be considered. The study of organelle distribution and organisation would support in vitro maturation and oocyte development fields, as well as their use as biological markers for quality determination. These findings will contribute to a better understanding of oogenesis/folliculogenesis processes in fish.
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Nicholas, Cory Robert. "Embryonic stem cell-derived oocyte development in follicles by transplantation into an endogenous ovarian niche". Diss., Search in ProQuest Dissertations & Theses. UC Only, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3378500.
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Thesis (Ph.D.)--University of California, San Francisco, 2009.Source: Dissertation Abstracts International, Volume: 70-10, Section: B, page: 5937. Advisers: Renee A. Reijo Pera; Michael S. German.
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Hreinsson, Julius. "Preservation of fertility through cryopreservation and in vitro maturation of human ovarian follicles and oocytes /". Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-698-7.
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[Verfasser], Mardiyanto, e Marc [Akademischer Betreuer] Schneider. "Investigation of nanoparticulate formulation intended for caffeine delivery to hair follicles / Mardiyanto. Betreuer: Marc Schneider". Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2013. http://d-nb.info/1053030959/34.
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Li, Shengbin, Joy M. Folkvord, Eva G. Rakasz, Hadia M. Abdelaal, Reece K. Wagstaff, Katalin J. Kovacs, Hyeon O. Kim et al. "Simian Immunodeficiency Virus-Producing Cells in Follicles Are Partially Suppressed by CD8+ Cells In Vivo". AMER SOC MICROBIOLOGY, 2016. http://hdl.handle.net/10150/622522.
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Human immunodeficiency virus (HIV)- and simian immunodeficiency virus (SIV)-specific CD8(+) T cells are typically largely excluded from lymphoid B cell follicles, where HIV- and SIV-producing cells are most highly concentrated, indicating that B cell follicles are somewhat of an immunoprivileged site. To gain insights into virus-specific follicular CD8(+) T cells, we determined the location and phenotype of follicular SIV-specific CD8(+) T cells in situ, the local relationship of these cells to Foxp3(+) cells, and the effects of CD8 depletion on levels of follicular SIV-producing cells in chronically SIV-infected rhesus macaques. We found that follicular SIV-specific CD8(+) T cells were able to migrate throughout follicular areas, including germinal centers. Many expressed PD-1, indicating that they may have been exhausted. A small subset was in direct contact with and likely inhibited by Foxp3(+) cells, and a few were themselves Foxp3(+) In addition, subsets of follicular SIV-specific CD8(+) T cells expressed low to medium levels of perforin, and subsets were activated and proliferating. Importantly, after CD8 depletion, the number of SIV-producing cells increased in B cell follicles and extrafollicular areas, suggesting that follicular and extrafollicular CD8(+) T cells have a suppressive effect on SIV replication. Taken together, these results suggest that during chronic SIV infection, despite high levels of exhaustion and likely inhibition by Foxp3(+) cells, a subset of follicular SIV-specific CD8(+) T cells are functional and suppress viral replication in vivo These findings support HIV cure strategies that augment functional follicular virus-specific CD8(+) T cells to enhance viral control.
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Robin, Frédérique. "Modeling and analysis of cell population dynamics : application to the early development of ovarian follicles". Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS344.
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Cette thèse vise à concevoir et analyser des modèles de dynamique des populations dédiés à la dynamique des cellules somatiques durant les premiers stades de la croissance du follicule ovarien. Les comportements des modèles sont analysés par des approches théoriques et numériques, et les valeurs des paramètres sont calibrées en proposant des stratégies de maximum de vraisemblance adaptées à notre jeu de données spécifique. Un modèle stochastique non linéaire, qui tient compte de la dynamique conjointe entre deux types cellulaires (précurseur et prolifératif), est dédié à l'activation de la croissance folliculaire. Une approche rigoureuse de projection par états finis est mise en œuvre pour caractériser l'état du système à l'extinction et calculer le temps d'extinction des cellules précurseurs. Un modèle linéaire multi-type structuré en âge, appliquée à la population de cellules prolifératives, est dédié à la croissance folliculaire précoce. Les différents types correspondent ici aux positions spatiales des cellules. Ce modèle est de type décomposable ; les transitions sont unidirectionnelles du premier vers le dernier type. Nous prouvons la convergence en temps long du modèle stochastique de Bellman-Harris et de l'équation de McKendrick-VonFoerster multi-types. Nous adaptons les résultats existants dans le cas où le théorème de Perron-Frobenius ne s'applique pas, et nous obtenons des formules analytiques explicites pour les moments asymptotiques des nombres de cellules et de la distribution stationnaire en âge. Nous étudions également le caractère bien posé du problème inverse associé au modèle déterministeThis thesis aims to design and analyze population dynamics models dedicated to the dynamics of somatic cells during the early stages of ovarian follicle growth. The model behaviors are analyzed through theoretical and numerical approaches, and the calibration of parameters is performed by proposing maximum likelihood strategies adapted to our specific dataset. A non-linear stochastic model, that accounts for the joint dynamics of two cell types (precursors and proliferative), is dedicated to the activation of follicular growth. In particular, we compute the extinction time of precursor cells. A rigorous finite state projection approach is implemented to characterize the system state at extinction. A linear multitype age-structured model for the proliferative cell population is dedicated to the early follicle growth. The different types correspond here to the spatial cell positions. This model is of decomposable kind; the transitions are unidirectional from the first to the last spatial type. We prove the long-term convergence for both the stochastic Bellman-Harris model and the multi-type McKendrick-VonFoerster equation. We adapt existing results in a context where the Perron-Frobenius theorem does not apply, and obtain explicit analytical formulas for the asymptotic moments of cell numbers and stable age distribution. We also study the well-posedness of the inverse problem associated with the deterministic model
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Joyce, Ieuan Michael. "Ovarian responses of ewes to growth hormone and gonadotrophin treatment". Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243681.
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Keough, Rebecca Anne. "An investigation of hair follicle cell immortalisation and hair keratin gene regulation /". Title page, table of contents and summary only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phk373.pdf.
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Moore, Anthony G., University of Western Sydney e School of Science. "The role of the extracellular matrix in wool follicle development". THESIS_XXXX_SS_Moore_A.xml, 1999. http://handle.uws.edu.au:8081/1959.7/389.
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Molecular and behavioural characterisation of ovine dermal papilla cells performed in this study indicate they synthesise a highly specialised extracellular matrix (ECM). This is conserved between different species and distinguishes papilla cells from dermal fibroblasts with which they have a common origin. The composition of the dermal papilla ECM is temporally and spatially regulated during wool follicle development. It was shown that the ECM associated with dermal papilla cells in foetal sheep skin becomes specialised in regard to chondroitin sulphate synthesis prior to the appearance of follicle primordia. Chrondroitin sulphate and fibronectin were present in the ECM of dermal papilla cells throughout follicle development and during fibre production. Cellular differentiation antigen 44 was present in the ECM od papilla cells exclusively during the formation of dermal papilla, while laminin was present in the dermal papilla ECM of fibre producing follicles only. Co-operation between chondroitin sulphate, fibronectin, and CD44 in regulating the agrregative and proliferative behaviour of papilla cells was demonstrated in culture. Finally, the inhibition of proteoglycan synthesis in newborn mouse skin was found to disrupt the growth of existing follicles and the generation of new ones. Together these findings demonstrate that chondroitin sulphate is intimately associated with the earliest interactions between epithelial and mesenchymal cells during the formation of follicle primordia. It is likely that the interactions specifically involve fibronectin and CD44, and possibly other ECM molecules which have he effect of regulating the behaviour of papilla cellsDoctor of Philosophy (PhD)
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Elfituri, Abdullatif. "Investigating the regulatory role of Anti-Müllerian Hormone in the growing follicles of a monovulatory species". Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33570/.
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Evidence from recent research suggests that folliculogenesis is regulated by stage specific locally produced growth factors and hormones including mediators of proliferation, differentiation and angiogenesis. AMH has been identified as one of these potentially important local factors and in polyovulatory species has been implicated in the regulation of the follicles growth, throughout its developmental stages. However in monovulatory species, despite its circulating levels being use as a marker of ovarian reserve and its suggested link to the aetiology of PCOS, little is known about its role and the means of its control in the growing follicle. Using the sheep model, the over-riding objective of this research project was the further elucidation of the roles of AMH during the antral stages of follicular development in monovulatory species. It was hoped the work would also provide valuable insights into the aetiology of PCOS. The study has focussed on four main research goals: characterisation of GC and TCs in terms of AMH and AMHR2 expression; confirmation of the utilisation of a SMAD signal transduction pathway in GC and TCs; an androgen involvement in AMH production; and the elucidation of two putative mechanisms of AMH regulation. Both AMH and AMHR2 were found to be expressed in ovine GC and TCs, although levels of AMH mRNA in TCs were very low and may not be biologically relevant. The outcomes also confirmed that in both ovine GC and TCs, AMH binds to a receptor complex containing the type 2 AMH receptor and that this mediates transduction of an intra-cellular signal via the SMAD 1/5/8 pathway. This finding in TCs indicates that GCs derived AMH may act in a paracrine way on TCs, disputing the long held belief of AMH only functioning in an autocrine manner. The effect of androgens on AMH production in FSH-stimulated GCs was previously not clarified but in this present study a significant increase in steroidogenesis in the presence of a non-aromatisable androgen now suggests that androgens may have a direct role in the regulation of AMH production, and thus at least in part, be involved in the modulation of folliculogenesis. The final aspect of this project was to study novel inter-ovarian interactions. This focussed on the hypothesis that VEGF, a potent ovarian angiogenic factor, and SOX8, a member of the SOX family of transcription factors, could be involved in AMH regulation in GCs. Results indicate that the two VEGF variants associated with growing follicles (VEGF120 and VEGF164) may have direct roles in AMH regulation. While on the other hand, SOX8 may have a role in regulating folliculogenesis and altering oestradiol production, however, it was not shown that this effect was mediated via AMH regulation. In conclusion this present study, not only supports earlier work showing TCs responsiveness to AMH, but for the first time in a monovulatory species, provides compelling evidence that AMH signal transduction in TCs is via receptor complexes containing AMHR2. Collectively these studies indicate a probable regulatory loop between GC produced AMH and TC produced androgens. From these outcomes it seems likely that the AMH regulatory loop may involve fine-tuning by external stimuli. A further novel finding has been that the VEGF variants particularly associated with growing follicles, and the transcription factor SOX8 appear to have some involvement in a complex system of AMH regulation. These findings should help in the design of future studies to elucidate how perturbations in this complex configuration may be involved in the aetiology of common forms of anovulatory infertility.
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Davani, Davari Esmaeil. "The effect of JH on isozymes of Na§+/K§+-ATPase in ovarian follicles of Locusta migratoria". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ43376.pdf.
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Raber, Anne Susanne [Verfasser]. "Methods and models for the investigation ofthe uptake of nanoparticles into hair follicles / Anne Susanne Raber". Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2020. http://d-nb.info/121474026X/34.
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Sazzad, TM Shahriar. "An automated approach to identify nongrowing follicles using digitized images of type P63 histopathology ovarian slides". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2017. https://ro.ecu.edu.au/theses/2032.
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Many developing countries are still facing challenges with limited access to fertility health services. Women face problems in conceiving due to many factors such as increasing age. In vitro fertilization (IVF) treatments can assist these women but are considered too expensive. Medical pathology laboratories are searching for novel technologies that can improve microscopic slide testing of female ovarian reproductive tissues. Current electronic methods for the assessment of human ovaries are not suitable for analysis of ovarian reproductive tissues. Ultrasound method cannot be used to identify small ovarian Non-Growing Follicles (NGFs) that are responsible for reproduction. A computer assisted approach to overcome the problems associated with manual microscopic analysis of ovarian reproductive tissues could be beneficial in increasing the accuracy and speed of the analysis. Few studies have reported on the use of images and other artificial intelligence techniques for ovarian tissue samples and have mostly concentrated on the analysis of cancer cells or ovarian animal tissues which are different from human ovarian reproductive tissues. Other studies using human ovarian reproductive tissues have been limited in terms of accuracy. This research examines the possibility of developing an automated computer approach which will improve the practices of these pathology laboratories to analyse female ovarian reproductive tissues and assist medical practitioners to provide necessary fertility treatment. The objective of the research was to study existing computerized methods used in various tissue assessments; identify the gaps and limitations; and to propose a novel method on digitized colour images acquired from ovarian reproductive tissue slides. The following major research question has been addressed by the research study: “How to develop an automated approach to assist pathology experts to identify ovarian reproductive NGFs (Non-growing follicles) or simply ovarian reproductive tissues using digital images acquired from type P63 (counter and non-counter stained) histopathology ovarian biopsy slides?” In order to answer this question, the research was carried out in a number of phases to examine existing computerized techniques for impact assessment of the ovarian reproductive tissue analysis. The research used a mixed method approach based on a case study using experimental and engineering methodologies. The study also employed quantitative and statistical data analysis methods. The research was carried out as a series of research activities including data collection, image processing, development of proposed approach, assessment factors (different magnification and different stains), validation of results with manual microscopic analysis results and development of the framework. A series of 7 different approaches were examined which started with basic image analysis technique. Modification and further medications were carried out to find the best possible approach which maintains the “gold standard” criteria in comparison to manual microscopic analysis results. A novel proposed approach was developed which used two phases: (1) phase one include pre-processing (intensity correction, filter operation, colour image segmentation, intensity clustering, feature extraction approach to find out the most suitable features); and (2) phase two for identifications of potential ovarian NGFs using shape, size and colour features that were extracted in phase one. It was found that the accuracy rate was above 90% for all magnifications and stains used in this research study which maintains the “gold standard” criteria in comparison to manual microscopic analysis results. To increase the accuracy rate and to diminish the false error rate classification approach was incorporated. The proposed approach established the most effect techniques in comparison to existing available approaches. A novel intensity correction was proposed and incorporated at the beginning of pre-processing, fast reliable novel filter operation was developed and incorporated for filter operation, colour image segmentation was considered to use the colour features for identification of region of interest (ROIs) from other tissues, extraction of features to capture NGFs’ characteristics, and incorporation of domain knowledge to identify NGFs. Validation was carried out with experts’ manual microscopic analysis results and similar regions were analysed to minimize the experts’ observation variability issues to improve the accuracy rate. A prototype software tool was developed in MATLAB platform, which enables a non-expert to easily use and analyse the ovarian reproductive tissues without changing any processing parameter automatically by giving the image magnification and image type as input parameter. The proposed approach was found to reduce the time and effort required for the analysis without any human intervention. The novelty of the research is that the approach was fully automated; non-experts will be able to use this approach for analysis; and no change of processing parameter is essential for new image batch/batches. The approach was also accurate, reliable and provided repeatable results in comparison to manual microscopic analysis results. Further work could explore the modification of tissue parameters that could be used for other tissue analysis.
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Antunes, Gastal Gustavo Desire. "Fertility preservation of ovarian germ cells: the horse and deer models". OpenSIUC, 2016. https://opensiuc.lib.siu.edu/dissertations/1295.
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Preserving viability of frozen gametes and reproductive tissues is crucial to understand and overcome species-specificities in respect to the diversity in cryobiological properties and requirements among cell types and tissues. The use of different animal models to study ovarian tissue cryopreservation will help to uncover several important factors related to germ cells preservation. Horses (Equus ferus caballus) have been proven to be an excellent model for reproductive biology studies with implications for humans. White-tailed deer (Odocoileus virginianus) are one of the most abundant wild species in the United States, but little information about their reproductive features are known. Therefore, five studies were conducted in this Dissertation with the following general objectives: (i) to develop ovarian tissue cryopreservation techniques for horses and white-tailed deer species; and (ii) to determine the effects of ovarian tissue cryopreservation techniques on morphological and molecular mechanisms related to folliculogenesis in horse and white-tailed deer species. In study one, equine ovarian tissue was used to determine the ideal ovarian fragment size for better cooling resistance under storage at 4°C. In study two, equine ovarian tissues were used to determine the toxicity effect of cryoprotective agents on ovarian tissue pre- and post-cryopreservation. In study three, equine ovarian tissues were used to compare slow-freezing versus vitrification; and to determine the best cryoprotective agents for each cryopreservation method. In study four, white-tailed deer reproductive tracts were used to characterize the age effect on reproductive features. In study five, white-tailed deer ovarian tissue was used to compare slow-freezing versus vitrification methods to preserve preantral follicles under in vitro culture. The main findings of the horse studies were: (i) equine ovarian tissue can be stored at 4°C for up to 24 h when biopsy ovarian fragments are used; (ii) ethylene glycol seems to be a less harmful cryoprotectant agent to equine preantral follicles; and (iii) both slow-freezing and vitrification methods similarly preserved the follicle morphology after time of culture. The main findings of the white-tailed deer studies were: (i) aging caused quantitative and qualitative effects on the ovarian reserve of white-tailed deer; (ii) fresh ovarian tissue can be cultured for up to seven days preserving the tissue integrity; and (iii) fragments cryopreserved by vitrification had higher follicle viability during in vitro culture than by the slow-freezing method. In conclusion, this work demonstrated the viability to cryopreserve equine and white-tailed deer ovarian tissue. Furthermore, the frozen-thawed equine and white-tailed deer ovarian tissue can be cultured for up to seven days.
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Webb, Gabriela M., Shengbin Li, Gwantwa Mwakalundwa, Joy M. Folkvord, Justin M. Greene, Jason S. Reed, Jeffery J. Stanton et al. "The human IL-15 superagonist ALT-803 directs SIV-specific CD8+ T cells into B-cell follicles". AMER SOC HEMATOLOGY, 2018. http://hdl.handle.net/10150/626600.
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Sequestering of latent HIV in follicular helper T cells within B-cell follicles that largely exclude cytotoxic T cells is a major barrier to cellular immune-based approaches to eradicate HIV. Here, we show that the clinical-grade human interleukin-15 (IL-15) superagonist ALT-803 activates and redirects simian immunodeficiency virus (SIV)-specific CD8+ T cells from the peripheral blood into B-cell follicles. In agreement with the increased trafficking of SIV-specific cytotoxic T cells to sites of cryptic viral replication, lymph nodes of elite controlling macaques contained fewer cells expressing SIV RNA or harboring SIV DNA post-ALT-803 treatment. These data establish ALT-803 as an immunotherapeutic for HIV and other chronic viral pathogens that evade host immunity by persisting in B-cell follicles.
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Pansera, Melissa. "Glucose transporter 1 expression, induction and transcriptional regulation in the granulosa cells of ovulating follicles in mice". Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123164.
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In response to the preovulatory luteinizing hormone (LH) surge, granulosa cells of ovulating follicles undergo luteinization resulting in the formation of the corpus luteum (CL). During this process granulosa cells acquire the steroidogenic ability to synthesize progesterone, which is an energetically demanding process. Indeed, LH is known to increase glucose uptake in the luteinized rat ovary, but the mechanisms have not been explored. Glucose uptake by cells is mediated by a family of facilitative glucose transporter (GLUT) proteins. These proteins facilitate the bi-directional passive transport of glucose. Of the 14 GLUTs, isoforms 1-4 are the best characterized. Glucose transporter isoforms have been identified in ovarian cells, but there remains controversy and uncertainty as to which isoforms are expressed in granulosa cells. The developmental profiles of GLUTs throughout the follicular and luteal phases, along with their transcriptional regulation have not been explored in granulosa cells. This research aimed to identify GLUT isoforms found in granulosa cells at specific stages of ovarian development using the mouse model. Preliminary experiments showed that the glucose transporter 1 isoform displayed an interesting profile and consequently this isoform is the focus of this study.Immature female mice were superstimulated using the exogenous hormones equine chorionic gonadotropin (eCG) and human CG (hCG), which promote follicular development and ovulation, respectively. Granulosa cells were collected by follicular puncture at specific time-points during superovulation. The mRNA profiles for the 4 Glut isoforms was carried out using quantitative PCR (qPCR). Following the identification of Glut1 in granulosa cells, the Fluorescent glucose cell-based uptake kit (Cayman Chemicals) was used to determine the glucose uptake of granulosa cells in primary culture. Pharmacological inhibition of the MAPK and mTOR pathways was carried out to identify the signaling cascade involved in Glut1 expression. Comparative bioinformatic analysis was used to determine transcriptional regulation of the mouse Glut1 promoter region, followed by chromatin immunoprecipitation (ChIP) to validate the in silico results. This study confirms the LH-stimulated glucose uptake, shows for the first time in granulosa cells that Glut1 is potentially responsible for increased glucose uptake after the LH surge and outlines the signaling pathways involved in Glut1 expression and transcription.En réponse à l'augmentation pré-ovulatoire de l'hormone lutéinisante (LH) , les cellules de la granulosa des follicules ovulatoires subissent la lutéinisation et forment le corps jaune (CL). Au cours de ce processus, les cellules de la granulosa acquièrent la capacité de synthétiser le progestérone, un processus qui nécessite beaucoup d'énergie. En effet, la LH est connu pour sont effet stimulant sur l'absorption du glucose dans l'ovaire lutéinisé chez le rat, mais les mécanismes n'ont pas été explorés. L'absorption du glucose par les cellules est médiée par une famille de transporteurs de glucose (GLUT) qui permettent le transport passif de glucose. Les isoformes Glut 1-4 sont les mieux caractérisées. Les isoformes de Gluts ont été identifiées dans les cellules ovariennes, mais il n'est pas clair quelles isoformes sont exprimées dans les cellules de la granulosa. Les profils d'expression des isoformes Gluts au cours du développement folliculaire et lutéale, aussi bien que leur régulation transcriptionnelle, n'ont pas été explorés dans les cellules de la granulosa. La présente recherche vise à identifier les isoformes des Gluts trouvées dans les cellules de la granulosa à des étapes spécifiques de la dynamique de l'ovaire chez la souris. L'eCG et l' hCG qui favorisent le développement folliculaire et l'ovulation, respectivement, ont été administrées à des souris femelle immatures. L'abondance de l'ARNm des quatre isoformes Glut dans des cellules de la granulosa ont été recueillies aux points de contrôle spécifiques au cours du cycle oestral. Suite à l'identification de Glut1 dans les cellules de la granulosa, le kit Fluorescent glucose cell-based uptake kit (Cayman Chemicals) a été utilisé pour déterminer l'absorption du glucose par les cellules de la granulosa en culture primaire.L'inhibition pharmacologique de MAPK et mTOR a été effectuée afin d'identifier la cascade de signalisation impliquée dans l'expression de Glut1. L'analyse bioinformatique a été utilisée pour déterminer la régulation transcriptionnelle du promoteur de Glut1 de la souris, suivie par l'immunoprécipitation de la chromatine (ChIP) pour valider ces résultats in silico. Cette étude confirme que l'absorption de glucose est en effet stimulée par la LH, montre pour la première fois dans les cellules de la granulosa que Glut1 est potentiellement responsable de l'augmentation de l'absorption du glucose après le pic de LH et décrit les voies de signalisation impliquées dans l'expression et la transcription de Glut1.