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1
Koothan, Thillai. "Structural and functional analysis of zona pellucida". Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/19905.
Testo completoAbstract (sommario):
The ability of the zona pellucida to mediate the species specific recognition of spermatozoa is due to a glycoprotein constituent of this structure, known as ZP3. In view of its important role in the initiation of fertilization, ZP3 has been identified as a suitable candidate for the development of a contraceptive vaccine. In order to generate recombinant marmoset ZP3 for immunization purposes a full length 1.3 kb insert encoding for marmoset ZP3 was cloned downstream of the malE gene to generate a fusion protein containing marZP3 and a maltose binding domain. This protein was found to be generated in a soluble form in aqueous solutions and the antigenic integrity of this molecule was demonstrated by it capacity to be recognized by a monoclonal antibody raised against human ZP3. This full length fusion protein has been purified by anion exchange chromatography and used to generate polyclonal antibodies. In addition to these in vitro studies on the generation of a recombinant marZP3 for active immunization purposes, in vivo studies have also been performed on the induction of active immunity against porcine ZP3. These studies have demonstrated that an important side effect of induction of immunity against a heterologous ZP3 antigen involves the depletion of the primordial follicle pool. Moreover this pathology could be transferred to non-immunized recipients by the passive transfer of antibody. These data raise the important question as to whether a similar pathology would be induced if homologous zona antigens were used for the induction of immunity. As a result of the work descriebd in this thesis, this question can now be addressed in the marmoset monkey using recombinant marZP3 as antigen.
2
Chapman, Jamie. "The marsupial zona pellucida : its structure and glycoconjugate content". Title page, abstract and contents only, 2003. http://web4.library.adelaide.edu.au/theses/09PH/09phc4661.pdf.
Testo completoAbstract (sommario):
Bibliography: leaves 262-298. This thesis investigated the structure and glycoconjugate composition of the zona pellucida (ZP) surrounding marsupial oocytes and the changes that occur during ovarian development, following ovulation, and following cortical granule exocytosis. The glycoconjugates of the oviduct epithelial lining of the brushtail possum around the time of ovulation were also examined to determine if there was any contribution of the oviductal secretions to the post-ovulatory ZP.
3
Gaboriau, David Claude Andre. "Binding of boar sperm proacrosin to the zona pellucida". Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613079.
Testo completo
4
Chung, Man-kin, e 鍾文健. "Biological characterization of cumulus glycodelin on humanspermatozoa-zona pellucida interaction". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42182633.
Testo completo
5
Lacey, Helen Ann. "Production and characterisation of recombinant human zona pellucida glycoprotein 2". Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322910.
Testo completo
6
Witzendorff, Dorothee von. "Das Glykom und Proteom der porcinen Zona pellucida ein massenspektrometrischer Ansatz /". [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=981929931.
Testo completo
7
Pfisterer, Susanne Charlotte Martha. "Herstellung, Charakterisierung und Einsatz von anti-Zona pellucida Protein 3 Peptidantiseren". [S.l.] : [s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=958759006.
Testo completo
8
Chung, Man-kin. "Biological characterization of cumulus glycodelin on human spermatozoa-zona pellucida interaction". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42182633.
Testo completo
9
Ringleb, Jennifer. "Identifikation antigener Determinanten des ZPB2-Proteins der Hauskatze und Charakterisierung ihrer kontrazeptiven und immunogenen Eigenschaften". Phd thesis, [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=974115282.
Testo completo
10
Törmälä, R. M. (Reeta-Maria). "Human zona pellucida abnormalities:a genetic approach to the understanding of fertilization failure". Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526212982.
Testo completoAbstract (sommario):
Abstract Despite the development of assisted reproduction technologies and significant advances in reproductive biology and medicine over the years the cause of infertility remains unexplained in 10–20% of cases. The cause of infertility in these cases may be connected to problems in fertilization or implantation and genetic factors may play a part in this. The zona pellucida (ZP) is an extracellular matrix surrounding the oocyte and early-stage embryos. It is important for folliculogenesis, fertilization and implantation. In humans, it is composed of four known ZP glycoproteins that all show varying degrees of structural and functional roles in reproduction. The aim of the present study was to examine the role of zona pellucida genes in cases of total fertilization failure and zona anomalies, and to study their expression in human fetal and adult ovaries. A total of 34 sequence variations were detected in genes expressing the four human ZP proteins (ZP1–ZP4) among women with fertilization failure and those with varying degrees of zona anomalies in their oocytes. Most of the variations were known single nucleotide polymorphisms, while three were novel findings. Women with fertilization failure had a higher mean number of sequence variations in ZP1 and ZP3 when compared with controls. Some of the most frequent zona anomalies may be at least partly explained by sequence variations in ZP1–ZP4 genes. In fetal life, the expression of ZP3 protein and mRNA could already be detected as early as at the 11th week of gestation and it peaked at the 20th week, the time of primordial follicle formation. This suggests that components needed for zona matrix are already present well before the formation of the zona pellucida and may have a role in the development of primordial follicles. Expression of the transcription factor FIGLA (factor in the germline alpha) was increased at around the 20th week of gestation, supporting previous findings of its critical role in the initiation of folliculogenesis and primordial follicle formation. The present study adds to our knowledge on the currently still incomplete picture of formation of the ZP and fertilization in humans. Understanding the genetic background of infertile patients may help us to develop new tools not only to evaluate but also to improve their fertilization potential, and to choose the optimal treatment to achieve pregnancyTiivistelmä Diagnostiikan kehityksestä huolimatta hedelmättömyyden syy jää edelleen epäselväksi 10–20 %:ssa tapauksista. Niissä hedelmättömyyden taustalla voivat olla munasolun hedelmöittymiseen ja kohtuun kiinnittymiseen liittyvät ongelmat, jotka voivat osittain johtua geneettisistä syistä. Alkiokuori on munasolua ja varhaista alkiota ympäröivä rakenne, joka osallistuu munarakkulan kehittymiseen, munasolun hedelmöittymiseen ja alkion tarttumiseen kohdun limakalvolle. Ihmisellä alkiokuori muodostuu neljästä tunnetusta alkiokuoriproteiinista (ZP1–ZP4). Tutkimuksessa selvitettiin alkiokuoriproteiineja koodittavien geenien vaikutusta hedelmällisyyteen potilailla, joilla koeputkihedelmöitys ei ollut tuottanut yhtään hedelmöittynyttä munasolua (engl. total fertilization failure, TFF) tai joiden munasoluissa havaittiin alkiokuoren rakennemuutoksia (engl. zona anomalies, ZA). Lisäksi selvitettiin alkiokuoriproteiinien ja niiden lähetti-RNA:n esiintymistä sikiöiden ja aikuisten munasarjoissa. TFF- ja ZA-potilaiden alkiokuoriproteiineja koodittavista geeneistä löytyi yhteensä 34 nukleotidimuutosta. Muutoksista kolme oli uusia löydöksiä, mutta suurin osa oli ennalta tunnettuja yhden nukleotidin polymorfioita eli geneettisiä monimuotoisuuskohtia. TFF-potilailla havaittiin ZP1- ja ZP3-geeneissä keskimäärin enemmän polymorfioita kuin verrokeilla. Myös osa yleisimmistä alkiokuoren rakennemuutoksista voidaan mahdollisesti selittää ZP1–ZP4-geeneistä löytyneillä polymorfioilla. Sikiöllä ZP3:n ilmentyminen oli havaittavissa jo 11. raskausviikolla, mutta voimakkainta se oli primordiaalivaiheen munarakkuloiden muodostumisen aikaan 20. raskausviikolla. Tämä voi viitata siihen, että ZP3 saattaa osallistua primordiaalivaiheen munarakkulan kehittymiseen ennen varsinaisen alkiokuoren muodostumista. ZP-geenien säätelytekijän FIGLA:n esiintyminen lisääntyi 20. raskausviikolla, mikä tukee aikaisempia havaintoja FIGLA:n merkityksestä munarakkulan kehittymisen aktivaatiossa ja primordiaalivaiheen munarakkuloiden muodostumisessa. Tämä tutkimus tuo lisätietoa alkiokuoren merkityksestä munasolun hedelmöittymisessä ja syventää tietämystämme alkiokuoren muodostumisesta ihmisellä. Hedelmättömyyden taustalla olevien geneettisten tekijöiden tunteminen voi parantaa lapsettomuuspotilaiden hedelmällisyyden arviointia ja auttaa löytämään heille parhaiten sopivan hoidon
11
Hägele, Wolfgang. "Herstellung, Charakterisierung und Einsatz von Anti-Zona pellucida-Protein 2-Peptid-Antiseren". [S.l.] : [s.n.], 1998. http://bibd.uni-giessen.de/gdoc/1998/uni/D980008.PS.
Testo completo
12
Balbach, Melanie [Verfasser]. "Action of zona pellucida glycoproteins in mouse and human sperm / Melanie Balbach". Bonn : Universitäts- und Landesbibliothek Bonn, 2017. http://d-nb.info/1166754790/34.
Testo completo
13
Bastiaan, Hadley Saville. "The effect of solubilized homologous zona pellucida on the human acrosome reaction, sperm-zona binding and motion characteristics of capacitated human spermatozoa". Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53630.
Testo completoAbstract (sommario):
Thesis (PhD)--Stellenbosch University, 2003.ENGLISH ABSTRACT: CHAPTER 1 provides literature based background information to emphasize the use of a sequential, multistep diagnostic schedule for couples in an assisted reproductive program as well as the clinical importance of sperm morphology as recorded by strict criteria during the diagnostic approach of the infertile couple. Furthermore, the chapter includes evidence underlining the growing need for the implementation of the physiologically induced acrosome reaction as an important contribution to the assisted reproductive program. The zona pellucida-induced acrosome reaction (ZIAR), sperm-zona interaction as well as computer-assisted semen analyses were investigated. CHAPTER 2 provides detailed experimental protocols of the materials and methods used in the study. CHAPTERS 3-6 each represent a separate study that was prepared as a scientific paper and encompass the experimental research undertaken in the reproductive biology research laboratory at Tygerberg Hospital to address important aspects of human acrosome processes. In the first study, we aimed to evaluate the regulatory role of the Gi-like protein during the AR of normal sperm donors and the role of intact acrosomes during sperm-zona binding. It seems that pertussis toxin-sensitive Gi-like protein in human spermatozoa plays an important regulatory role in the ZIAR and this underlines the importance of intact acrosomes during sperm-zona binding. In the second study, we aimed to evaluate the relationship between the ZIAR and the percentage normal spermatozoa as well as the sperm-ZP binding potential among men referred for a routine semen analysis. ZIAR testing should become part of the second level of male fertility investigations, i.e., sperm functional testing, since 15% of the andrology referrals revealed an impaired AR response to solubilized ZP. In the third study, we aimed to evaluate the possible relationships between the sperm morphology, the acrosome responsiveness to solubulized human ZP and the sperm-zona binding potential among consecutive andrology referrals and randomly selected IVF cases. ZIAR results provide further information regarding dysfunctional sperm and can be used as an additional diagnostic test since the results predicted fertilization failure during IVF treatment. In the fourth study, we aimed to evaluate changes in the sperm motion characteristics and the occurrence of hyperactivated motility after exposure to ZP among andrology referrals. Solubilized human ZP induces hyperactivated motility among sperm populations that have been capacitated under laboratory conditions. Capacitated spermatozoa have an elevated percentage hyperactivated cells that correlate with the percentage normal spermatozoa in the ejaculate. CHAPTER 7, the general discussion, is brief and concise to avoid unnecessary repetition, underlines the validity of a sequential, multistep diagnostic approach and concludes with the recommendation that the ZIAR should form part of the diagnostic tools in the assisted reproductive program.
AFRIKAANSE OPSOMMING: HOOFSTUK 1 bestaan uit ’n omvattende agtergrondstudie wat bestaan uit die ontwikkeling van diagnostiese toetse, die hantering van die egpaar in die reproduktiewe ondersteunings-program asook op die kliniese belang van spermmorfologie. Die toenemende behoefte aan die implementering van die fisiologies-geinduseerde akrosoomreaksie, as ’n belangrike bydrae tot die reproduktiewe ondersteuningsprogram, word ook beklemtoon. Die zona pellucida geinduseerde akrosoomreaksie (ZIAR), sperm-zonabinding asook rekenaar-bemiddelde semenanalises is ondersoek. HOOFSTUK 2 dek gedetailleerde eksperimentele protokolle van die materiale en metodes wat in die studie gebruik is. HOOFSTUKKE 3-6 behandel die eksperimentele navorsing wat in die laboratorium van die reproduktiewe biologie-eenheid te Tygerberg hospitaal uitgevoer is en wat as ses afsonderlike wetenskaplike publikasies aangebied word. Die doel van die eerste studie was om die regulerende rol van Gi-proteiene tydens die AR van normale spermdonors asook die rol van intakte akrosome tydens sperm-zonabinding te evalueer. Dit kom voor asof Gj-protei'ene in spermatozoa ’n belangrike regulerende rol in die ZIAR speel. Dit beklemtoon die belangrikheid van intakte akrosome tydens sperm-zonabinding. Die doel van die tweede studie was om die verhouding tussen die ZIAR en die persentasie normale spermatozoa asook die sperm-zonabindingspotensiaal tussen mans wat vir ’n roetine semenanalise verwys is te evalueer. ZIAR-toetsing moet deel uitmaak van die tweede vlak van manlike fertiliteitsondersoeke, d.w.s. funksionele toetsing, aangesien 15% van die andrologie pasiente ’n verswakte AR respons tot opgeloste ZP openbaar. In die derde studie was die doel om die moontlike verhoudinge tussen sperm-morfologie, die ZIAR en die sperm-zonabindingspotensiaal onder opeenvolgende andrologie-pasiente asook lukraak geselekteerde IVB-pasiente te evalueer. Die ZIAR-resultate bied verdere informasie aangaande disfunksionele spermatozoa en kan gebruik word as ’n addisionele diagnostiese toets aangesien hierdie resultate mislukte bevrugting tydens IVB behandeling voorspel. Die vierde studie het ten doel gehad om veranderinge in spermmotiliteitseienskappe asook hiperaktiwiteit na die blootstelling aan opgeloste zona onder andrologiepasiente te evalueer. Daar is afgelei dat opgeloste menslike zona hiperaktiwiteit induseer in spermpopulasies wat onder gunstige laboratoriumkondisies gekapasiteer is. Die gekapasiteerde spermatozoa het ’n verhoogde persentasie gehiperaktiveerde spermatozoa getoon wat met die persentasie normale spermatozoa in die ejakulaat korreleer. In HOOFSTUK 7 word aangetoon dat dit noodsaaklik is om die diagnostiese skedule by die hantering van die onvrugbare egpaar te gebruik asook dat die ontwikkeling van die funksionele toestand belangrik is vir die bepaling van ZIAR.
14
Lowe, Jeanette. "Phage Display to Identify Peptides Binding to or Penetrating the Mouse Zona Pellucida". Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/35902.
Testo completoAbstract (sommario):
The objective of this study was to identify peptide ligands, using phage display techniques, which bind sites on mouse embryos, ovaries, cytoplasmic membranes and/or intracytoplasmic components. Specifically, M13 coliphage 7-mer, 12-mer and 15-mer random peptide libraries were used separately for biopanning. Peptides derived from the amplified pools were sequenced and studied. The phage display for in vivo ovary experiments yielded no pool of peptides after two cycles of biopanning and re-amplification. With the same initial concentration of a random 7-mer or 12-mer library, there were repeating sequences derived after three and four biopanning cycles on mouse embryos and unfertilized ova. The sequences were not distinguishable from a control group. Subsequent experimentation using a random 15-mer library to select for internalized phage-peptides yielded two apparent consensus sequences, RNVPPIFNDVYWIAF (9/32 or 28%) and HGRFILPWWYAFSPS (11/32 or 34%). The 15-mer control group yielded no clones. The deduced peptide sequences were compared to known sequences to ascertain their uniqueness. No significant similarities were found, yielding two possible novel motifs. Through this adapted process of phage display and further research, the phage display technology may be used as a tool in the recognition of specific mouse gamete sites. By identifying binding sites of mouse gametes, the peptides might be exploited as a means of studying the embryo cell surface or cytoplasmic components and mouse sperm-egg interactions. Such peptides may also be used for macromolecule delivery in transfection or transgenesis.Master of Science
15
Lunn, Matthew O'Brien. "A Morphological Study of the Canine Zona Pellucida: A Heterogeneous Ultrastructure and Barrier". University of Dayton / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1311785290.
Testo completo
16
au, joyceand@iinet net, e Jocye A. Eade. "Investigating porcine and feline zona pellucida as immunocontraceptive antigens in the female domestic cat". Murdoch University, 2007. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070717.124229.
Testo completoAbstract (sommario):
Immunocontraception, or contraception mediated by the immune system, is being
widely studied as an alternative, humane form of population control. The induction of
an immune response against a specific component of the mammalian oocyte, termed
zona pellucida (ZP) has been shown to be an effective immunocontraceptive in several
species. Comparatively little work has been done investigating the use of ZP antigens
in the domestic cat. This study aimed to investigate porcine ZP(B+C) and feline ZPA,
B and C as immunogens in the domestic cat, and further to elucidate their effects on
reproduction. Immunisation of female cats with porcine ZP(B+C) failed to elicit a
detectable antibody response as assessed by ELISA, immunoblotting and
immunohistochemistry. Additionally, there was no effect on the structure of the ovaries
nor on breeding performance. Feline ZPA, B and C were cloned into the
pkCMVint.polyli mammalian expression vector and used to immunise female cats.
ELISA revealed that immunisation with either pkCMVint.fZP(B+C) or pkCMVint.fZPA
DNA (Treated) resulted in a low-level circulating antibody response, which was
apparently short-lived. Immunoblotting did not reveal any common pattern of
recognition of antigenic polypeptides between responding animals. Ovaries from fZP
Treated animals, however, showed antibody binding specifically on the ZP of follicles
from late primary / early secondary, through to antral stages. Despite the antibody
binding, the overall structure of the ovaries remained unaffected in all but two of the
fZP Treated cats. Two fZPA immunised cats exhibited ovaries that had no
recognisable follicular structures, however, the observed abnormalities could not be
conclusively linked to fZPA immunisation. Overall, a significant lymphoproliferative
response was shown in fZP Treated cats when compared with Controls. Fertility was
not significantly affected in fZP Treated cats, although there was a tendency towards
increased incidence of unsuccessful matings or pregnancies. The fZP DNA
preparations studied here exhibit potential as an immunocontraceptive, with the ability
to generate a lymphoproliferative response against fZP and elicit antibodies
specifically recognizing fZP in situ. Further studies should continue to investigate the
immunogenicity of, and characterise the immune response against, such fZP DNA
preparations.
17
Eade, Joyce A. "Investigating porcine and feline zona pellucida as immunocontraceptive antigens in the female domestic cat /". Access via Murdoch University Digital Theses Project, 2007. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20070717.124229.
Testo completo
18
Wong, Siu-tak, e 黃兆德. "Priming effect of glycodelin-A on zona pellucida induced acrosome reaction in human spermatozoa". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41508439.
Testo completo
19
Wong, Siu-tak. "Priming effect of glycodelin-A on zona pellucida induced acrosome reaction in human spermatozoa". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41508439.
Testo completo
20
Eade, Jocye A. "Investigating porcine and feline zona pellucida as immunocontraceptive antigens in the female domestic cat". Thesis, Eade, Jocye A. (2007) Investigating porcine and feline zona pellucida as immunocontraceptive antigens in the female domestic cat. PhD thesis, Murdoch University, 2007. https://researchrepository.murdoch.edu.au/id/eprint/59/.
Testo completoAbstract (sommario):
Immunocontraception, or contraception mediated by the immune system, is being widely studied as an alternative, humane form of population control. The induction of an immune response against a specific component of the mammalian oocyte, termed zona pellucida (ZP) has been shown to be an effective immunocontraceptive in several species. Comparatively little work has been done investigating the use of ZP antigens in the domestic cat. This study aimed to investigate porcine ZP(B+C) and feline ZPA, B and C as immunogens in the domestic cat, and further to elucidate their effects on reproduction. Immunisation of female cats with porcine ZP(B+C) failed to elicit a detectable antibody response as assessed by ELISA, immunoblotting and immunohistochemistry. Additionally, there was no effect on the structure of the ovaries nor on breeding performance. Feline ZPA, B and C were cloned into the pkCMVint.polyli mammalian expression vector and used to immunise female cats. ELISA revealed that immunisation with either pkCMVint.fZP(B+C) or pkCMVint.fZPA DNA (Treated) resulted in a low-level circulating antibody response, which was apparently short-lived. Immunoblotting did not reveal any common pattern of recognition of antigenic polypeptides between responding animals. Ovaries from fZP Treated animals, however, showed antibody binding specifically on the ZP of follicles from late primary / early secondary, through to antral stages. Despite the antibody binding, the overall structure of the ovaries remained unaffected in all but two of the fZP Treated cats. Two fZPA immunised cats exhibited ovaries that had no recognisable follicular structures, however, the observed abnormalities could not be conclusively linked to fZPA immunisation. Overall, a significant lymphoproliferative response was shown in fZP Treated cats when compared with Controls. Fertility was not significantly affected in fZP Treated cats, although there was a tendency towards increased incidence of unsuccessful matings or pregnancies. The fZP DNA preparations studied here exhibit potential as an immunocontraceptive, with the ability to generate a lymphoproliferative response against fZP and elicit antibodies specifically recognizing fZP in situ. Further studies should continue to investigate the immunogenicity of, and characterise the immune response against, such fZP DNA preparations.
21
Eade, Jocye A. "Investigating porcine and feline zona pellucida as immunocontraceptive antigens in the female domestic cat". Eade, Jocye A. (2007) Investigating porcine and feline zona pellucida as immunocontraceptive antigens in the female domestic cat. PhD thesis, Murdoch University, 2007. http://researchrepository.murdoch.edu.au/59/.
Testo completoAbstract (sommario):
Immunocontraception, or contraception mediated by the immune system, is being widely studied as an alternative, humane form of population control. The induction of an immune response against a specific component of the mammalian oocyte, termed zona pellucida (ZP) has been shown to be an effective immunocontraceptive in several species. Comparatively little work has been done investigating the use of ZP antigens in the domestic cat. This study aimed to investigate porcine ZP(B+C) and feline ZPA, B and C as immunogens in the domestic cat, and further to elucidate their effects on reproduction. Immunisation of female cats with porcine ZP(B+C) failed to elicit a detectable antibody response as assessed by ELISA, immunoblotting and immunohistochemistry. Additionally, there was no effect on the structure of the ovaries nor on breeding performance. Feline ZPA, B and C were cloned into the pkCMVint.polyli mammalian expression vector and used to immunise female cats. ELISA revealed that immunisation with either pkCMVint.fZP(B+C) or pkCMVint.fZPA DNA (Treated) resulted in a low-level circulating antibody response, which was apparently short-lived. Immunoblotting did not reveal any common pattern of recognition of antigenic polypeptides between responding animals. Ovaries from fZP Treated animals, however, showed antibody binding specifically on the ZP of follicles from late primary / early secondary, through to antral stages. Despite the antibody binding, the overall structure of the ovaries remained unaffected in all but two of the fZP Treated cats. Two fZPA immunised cats exhibited ovaries that had no recognisable follicular structures, however, the observed abnormalities could not be conclusively linked to fZPA immunisation. Overall, a significant lymphoproliferative response was shown in fZP Treated cats when compared with Controls. Fertility was not significantly affected in fZP Treated cats, although there was a tendency towards increased incidence of unsuccessful matings or pregnancies. The fZP DNA preparations studied here exhibit potential as an immunocontraceptive, with the ability to generate a lymphoproliferative response against fZP and elicit antibodies specifically recognizing fZP in situ. Further studies should continue to investigate the immunogenicity of, and characterise the immune response against, such fZP DNA preparations.
22
Bates, Melodie Joy. "Endocrine correlates of free-ranging African elephant (Loxodonta africana) treated with porcine zona pellucida vaccine". Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/25181.
Testo completoAbstract (sommario):
Due to overpopulation of African elephants in South Africa and the consequent threat to biodiversity, the need for a method of population control has become evident. The potential use of the porcine zona pellucida (pZP) vaccine as a safe and effective means for population control is explored. While potential effects of pZP treatment on social behaviour of African elephants have been investigated, no examination of the influence of pZP vaccination on the endocrine correlates in treated females has been undertaken. The ovarian activity of freeranging, pZP-treated African elephant females was monitored non-invasively for one year duration by measuring faecal progestagen concentrations via enzyme immunoassay. Behavioural observations were recorded for comparison with progestagen concentrations and to determine any behavioural changes surrounding the pZP vaccine darting event. Each elephant under study showed progestagen concentrations rising above baseline at some period during the study indicating luteal functionality. Average progestagen concentrations were 1.61 ± 0.46 ìg/g. Within sampled females, 42.9% exhibited oestrous cycles within the range reported for African elephants, 14.3% had irregular cycles, and 42.9% did not appear to be cycling. Average oestrous cycle duration was 14.72 ± 0.85 weeks. Behavioural oestrous coincided with the onset of the luteal phase and a subsequent rise in progestagen concentrations. Focal sampling to determine activity budgets before and after the darting event revealed no significant change in behavioural activities. In the week following immunization, individual progestagen concentrations decreased significantly from overall average concentrations. Average progestagen concentrations positively correlated with rainfall and with herd dominance. No association between average individual progestagen concentrations or cyclicity status with age, lactation, or parity were detected. Earlier determination of efficacy was made indicating reproductive control was established 22 months post-treatment. Results indicate the presence of ovarian activity amongst pZP-treated female African elephants in two years following initial immunization. Further study should be aimed toward studying the long term effects of pZP vaccination on the reproductive function of female African elephants.Dissertation (MSc)--University of Pretoria, 2010.
Production Animal Studies
unrestricted
23
Oehninger, Sergio C. "The interaction between human spermatozoa and its homologous zona pellucida : scientific advances and clinical significance". Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/53132.
Testo completoAbstract (sommario):
Thesis (PhD)--Stellenbosch University, 2002.ENGLISH ABSTRACT: Infertility is a very common problem worldwide. Recent data have shown that disorders of the male represent the most common single defined cause of infertility. This proposal examines the clinical significance and fundamental physiological aspects of human gamete interaction. These studies are focused on the assessment of the cellular-molecular mechanisms involved in human sperm binding to its homologous zona pellucida resulting in the physiologic induction of the acrosome reaction. We have developed and validated in vitro bioassays that assess specific steps of the fertilization process that are critical for early embryo development. The results of our translational research have already had a significant impact on the overall evaluation of male infertility and on the clinical management of the infertile man in the assisted reproduction arena. Furthermore, the unveiling of the basic mechanisms involved in human gamete interaction will ultimately allow for both (i) the development of new male reproductive diagnostic capabilities and (ii) the design of improved and safer therapies aiding conception in childless couples suffering from male infertility.
AFRIKAANSE OPSOMMING: Menslike onvrugbaarheid is 'n algemene wêreldwye probleem en onlangse data toon aan dat die manlike factor die grootste enkel bydraende factor tot hierdie toestand is. Die werk loods 'n intensiewe ondersoek na die kliniese betekenis en basiese fisiologiese aspekte wat 'n rol tydens spermsel en eisel interaksie speel. Hoofstuk 3 fokus op die sellulêre en molekulêre meganismes wat betrokke is tydens spermsel en eisel binding wat gevolglik lei tot akrosoomreaksie van die spermsel. Die werk verteenwoordig die resultate van 10 jaar se navorsing tussen die kandidaat en die promoter. Dit gee oorsprong aan 'n reeks bio-toetse wat die bevrugtingsproses koriografiese ontleed en verskaf dus 'n stap-vir-stap uiteenseting van menslike bevrugting en gevolglike embrio ontwikkeling. Die resultate in Hoostuk 4 bring vernuwing in die begrippe van die manlike faktor en die rol in die kinderlose huwelik. Die resulate soos in Hoofstuk 3 en 4 uiteengesit, vorm nie net die basis vir die moontlike ontwikkeling van nuwe diagnostiese benaderings tot die hantering van die man nies maar speel oojk 'n rol die daarstelling van verbeterde terapeutiese hantering van die kinderlose egpaar. Hoofstuk 5 gee kortliks riglyne en aanbevelings tot opsigte van die gebruik van die spermsel-zona pellucida bindingstoets en akrosomreaksie. Die kandidaat bevel aan dat die genoemde twee bio-toetse deel van die laboratorium ondersoeke van die man gebruik moet word.
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Kuske, Michael [Verfasser]. "Das Zusammenspiel der Proteasen Akrosin und Ovastacin bei der Härtung der Zona pellucida / Michael Kuske". Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2021. http://d-nb.info/1231433469/34.
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Kaskar, Khalied. "Evaluation of quantitative motility and zona pellucida binding of human spermatozoa in an assisted reproductive programme". University of the Western Cape, 1994. http://hdl.handle.net/11394/8416.
Testo completoAbstract (sommario):
>Magister Scientiae - MScMale factor disorders affect more than 30% of infertile couples. Thus, it has become important to perform a andrological consultation and a basic semen evaluation in all male partners of couples consulting for infertility. The advent and development of assisted reproductive technologies has not only improved clinical results but also enhanced our basic understanding of the physiology of sperm and sperm preparation methods. Assisted reproduction has become among the more successful therapeutic modalities for a wide variety of sperm function disorders e.g. artificial insemination and in vitro fertilization (IVF) (Acosta et al. 1989). It is clear from recent experience that patients with male infertility showing oligozoospermia, asthenozoospermia, teratozoospermia (sometimes in combination), male immunological factor (antisperm antibodies) or ejaculatory problems as well as congenital abnormalities, can be successfully treated with IVF and embryo transfer. Prerequisite pre-fertilization changes by sperm, termed "capacitation" (Austin 1952) provides sperm with the capacity to fertilize eggs. These processes are generally regarded as encompassing all pre-fertilization changes occurring in sperm up 'to, but not including, loss of the acrosome (Bedford 1970). The endpoints of capacitation are often described as the acrosomal loss as well as changes in the motion characteristics. Capacitation alters the pattern of motility exhibited by freely swimming sperm, changing from a fairly rigid flagellar beat pattern to one of extreme flexure, often associated with increased thrust (Johnson et al. 1981) , which is referred to as hyperactivated motility (Yanagimachi 1981). without the transition to hyperactivated motility, sperm are unable to penetrate the zona pellucida (Fraser 1981), and possibly unable to fertilize eggs. Hyperactivation per se is marked by increased curvature in swimming trajectories and/or increased lateral displacement of the sperm head along their path (Burkman 1984). However, the physiological role of this change in motility is not clearly understood because almost all relevant data have been obtained under in vitro conditions. The association of specific seminal characteristics (sperm concentration, percentage motile cells and percentage normal sperm morphology) with the success rate of assisted particular has been The analysis of 1984; the reproductive techniques and IVF in under great scrutiny (Mahadevan and Trounson relationships between conventional semen parameters and fertilization rates in vitro has shown that sperm motility, concentration and morphology must be considered in estimating opportunities for successful intervention, as in the case of IVF and gamete intrafallopian transfer (GIFT) (Oehninger and Hodgen 1991). A reduction in the percentage of progressive motility alone does not seem to have a significant impact on IVF results unless it is below a threshold value of 10%. The semen sample should have an acceptable sperm concentration and morphology and/or that at least 1.5 X 106 motile spermatozoa can be recovered after swim-up separation (Acosta et al. 1989).
26
Levy, Maria Patricia Morales. "Development of a DNA vaccine for population control : a zona pellucida based nucleic acid vaccine (ZP-NAV) /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
Testo completo
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Shahror, Rami Ahmad Nawaf. "Characterization of the Transcription Factor NF‐Y in the Regulation of Zona Pellucida Genes in Zebrafish Ovary". Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-30318.
Testo completoAbstract (sommario):
Zona pellucida glycoproteins (ZP) are important proteins for maturation of the oocytes in eukaryotes, these proteins are encoded by cluster of zp genes. zp2.3 and zp3.5 genes are expressed during the developing and maturation of the oocytes in zebrafish ovaries. Both of the gens have a CCAAT box in their promoter regions, playing a big role in the expression of the both genes in zebrafish oocytes. The transcription of the genes in the eukaryotes requires transcription factors to initiate and promote the transcription, the transcription factors can bind to the promoter region and initiate the transcription process. The nuclear factor y (NFY) regulates the genes by binding to the CCAAT boxes in their promoter regions, it consist from many subunit such as NF-YA and NF-YB. Here in this study we characterize the expression pattern of NF-YA and NF-YB by screening these genes expression in several organs and tissues, also to determine its roles in the expression of the zp2.3 and zp3.5 genes in the adultzebrafish ovary.
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Petersen, Claudia Guilhermino. "Correlação da maturação e da morfologia do oócito humano com as características do fuso meiótico e da zona pelúcida /". Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/106388.
Testo completoAbstract (sommario):
Orientador: José Gonçalves Franco JúniorBanca: Anice Maria Vieira Camargo Martins
Banca: Edson Borges
Banca: Jorge Nahas Filho
Banca: Ana Lúcia Kalinin
Resumo: Nas últimas décadas, alguns parâmetros laboratoriais têm sido propostos para identificar o potencial de saúde oocitária em Reprodução Assistida: 1. Maturidade nuclear e citoplasmática (pesquisa); 2. Dismorfismo (anomalias intracitoplasmáticas); 3. Fertilizaçao. Habitualmente, esses parâmetros (exceto a maturação citoplasmática) são avaliados pelo simples emprego de sistemas de microscopia de luz convencional. Nos últimos oito anos, foram relatados diversos estudos em oócitos humanos sobre a birrefringência da zona pelúcida (BF-ZP), a espessura da ZP, e a visualização do fuso meiótico (FM). Entretanto, ainda é discutível o poder desses novos parâmetros na seleção de óvulos com o pontecial de originar embriões com taxas de implantação elevadas, além disso, seu sistema de visualização e quantificação é complexo e dispendioso. O objetivo deste estudo foi investigar uma possível correlação entre esses parâmetros tradicionais com a BF-ZP, espessura da ZP e o FM. Dessa forma, um total de 73 pacientes que participaram do programa de injeção intracitoplasmática de espermatozóide (ICSI) no Centro de Reprodução Humana "Prof Franco Júnior" tiveram seus óvulos avaliados quanto a maturação nuclear (n=83), maturação citoplasmática (n=29), dismorfismo (n=280) e fertilização (n=216) sendo os resultados correlacionados com a imagem do FM (presença ou ausência), a intensidade da BF-ZP (positiva ou negativa) e a espessura da ZP. Os dados finais revelaram uma fraca correlação entre a maturação, o dismorfismo e a fertilização oocitária com a imagem do FM, a intensidade da BF-ZP, e a espessura da ZP. Entretanto, esses parâmetros poderiam ser responsáveis por identificar pontos biológicos diferentes do potencial de qualidade oocitária. Assim sendo, seria uma medida coerente, a utilização desses parâmetros, em forma conjunta, através de um escore de qualidade oocitária.
Abstract: During the last decades, three laboratorial parameters have been proposed to identify the potential of the oocyte quality in ART: 1- Nuclear and cytoplasmic maturation; 2-Dysmorphims (intracytoplasmic abnormalities); 3 - Fertilization. These parameters (except the cytoplasmic maturation) are assessed by a simple system of conventional light microscopy. In the last eight years, numerous studies about zona pellucida birefringence (BF-ZP), zona pellucida thickness and meiotic spindle visualization have been reported. However, it is still controversial the power of these parameters in selecting oocyte with potential to develop into implantation-competent embryos. Furthermore, the microscopy system is complex and expensive. The present study aims to evaluate whether there is any correlation between the classical parameters with BF-ZP, ZP thickness and spindle image. A total of 73 patients who participated in an ICSI program had their oocytes evaluated such nuclear maturation (n=83), cytoplasmic maturation (n=29), dysmorphism (n=280) and fertilization (n=216) being its results correlated to the spindle image (presence or absence), BF-ZP intensity (positive or negative) and ZP thickness. The final results showed a low correlation between maturation, dysmorphism and fertilization compared to spindle image and ZP characteristics (BF-ZP, ZP thickness). However, these factors can be responsible to identify specific biological differ from the oocyte potential. Concluding, the use of these factors in association, as a score (oocyte quality score), could be the correct evaluation.
Doutor
29
Gan, Yong Chen Zhen. "Model-based simulations of the piercing process in piezo-ICSI". Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/7111.
Testo completoAbstract (sommario):
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb. 23, 2010 ). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dr. Zhen Chen, Dissertation Supervisor. Vita. Includes bibliographical references.
30
Parkinson, Christine Anne. "Cloning and characterisation of a zebrafish cDNA encoding a novel member of the Zona pellucida family of proteins". Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271294.
Testo completo
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Du, Plessis S. S. (Simon Stephanus). "A study of the intracellular signalling events involved in the zona pellucida-induced acrosome reaction in human spermatozoa". Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52709.
Testo completoAbstract (sommario):
Thesis (PhD)--Stellenbosch University, 2002.ENGLISH ABSTRACT: In this study the author presents new data that will shed light on the fairly nebulous knowledge of intracellular pathways involved in the physiologically induced acrosome reaction and the subsequent events leading to fertilization. The zona pellucidainduced acrosome reaction, sperm-zona interaction as well as various sperm motion characteristics were investigated. The first part of the study focussed on the role of extracellular signal regulated kinase (ERK), a member of the family of mitogen activated protein kinases, during the zona pellucida-induced acrosome reaction and sperm-oocyte interaction. It was shown that the inhibition of ERK significantly reduced the zona pellucida-induced acrosome reaction as measured by fluorescent microscopy. This suggests that ERKs are directly or indirectly involved in the signal transduction pathway through which the human sperm acrosome reaction is induced by the zona pellucida. In an attempt to provide further proof that ERK was involved in human acrosome signalling hemizona assays were employed to test sperm-oocyte binding. From these sperm-oocytebinding experiments it was clear that the inhibition of ERK leads to increased binding. These results support the idea that the zona pellucida-induced acrosome reaction, and therefore the physiologically relevant exocytotic event, is regulated by an ERKmediated signal transduction process. In the second part of the study the significance of phosphatidylinositol 3-kinase (PI3K) in the process of human sperm motility, acrosome reaction and sperm-oocyte binding, was investigated by employing the specific PI3K, LY294002. PI3K inhibition increased the percentage motility and percentage progressive motility in asthenozoospermia patients. Under the present laboratory conditions PI3K inhibition furthermore did not influence the acrosome reaction, whilst it enhanced sperm-oocyte binding. These results therefore imply that PI3K negatively affect sperm motility and zona-binding. In the last part of the study the possible effects of intracellular cGMP accumulation via acute in vivo sildenafil citrate (ViagraTM) administration was investigated on seminal parameters, induction of the acrosome reaction, sperm-oocyte binding and sperm motility. As was expected no changes in the macro- and microscopically seminal parameters were caused by sildenafil citrate when compared to placebo. Furthermore the acrosome reaction was also not initiated or potentiated by sildenafil citrate at concentrations of 50mg orally. Sperm-oocyte binding, smooth path velocity, straight line velocity and the percentage rapid cells all increased after sildenafil citrate treatment. From these results it appear that there are various role players in the zona pellucidainduced acrosome reaction intracellular signalling system. A thorough understanding of such signal transduction systems and the crosstalk in-between will ultimately yield information regarding the nature of receptors to which these signal transduction pathways are coupled in human spermatozoa as well as the intracellular effectors that ultimately regulate sperm function. Moreover, an understanding of these regulatory pathways will be essential for the future development of clinical approaches designed to enhance or preclude fertilization.
AFRIKAANSE OPSOMMING: Die outeur lê in hierdie studie nuwe data voor ten einde meer lig te werp op die relatief vae veld van intrasellulêre seintransduksie paaie betrokke by die fisiologiesgeïnduseerde akrosoomreaksie en die daaropvolgende gebeure wat aanleiding gee tot bevrugting. Die zona pellucida-geïnduseerde akrosoomreaksie, sperm-zona interaksie sowel as spermmotiliteitseienskappe is ondersoek. Die eerste gedeelte van die studie fokus op die rol van ekstrasellulêreseingereguleerde- kinase (ERK), 'n lid van die familie van mitogeen-geaktiveerde proteïenkinases, tydens die zona pellucida-geïnduseerde akrosoomreaksie en sperm-oosiet interaksie. Daar word aangetoon dat die inhibisie van ERK die zona pellucida geïnduseerde akrosoomreaksie, soos gemeet met behulp van fluorosensie mikroskopie, betekenisvol verminder. Dit suggereer dat ERK direk of indirek betrokke is by die seintransduksie paaie waardeur die akrosoomreaksie van die menslike sperm deur die zona pellucida geïnduseer word. In 'n poging om onomwonde te bewys dat ERK betrokke is by menslike akrosoom-seintransduksie, is hemizona essais gebruik om sperm-oesiet binding te bepaal. Van hierdie sperm-oosiet bindingeksperimente is dit duidelik dat die inhibisie van ERK aanleiding gee tot verhoogde binding. Hierdie resultate ondersteun dus die idee dat die zona pellucidageïnduseerde akrosoomreaksie en dus die fisiologies relevante eksositotiese gebeurtenis gereguleer word deur 'n ERK-gemediëerde seintransduksie proses. In die tweede gedeelte van die studie is die belang van fosfatidielinositol 3-kinase (PI3K) in die proses van menslike spermmotiliteit, akrosoomreaksie en sperm-oesiet binding ondersoek deur van die spesifieke PI3K inhibitor LY294002, gebruik te maak. Pl3K-inhibisie het die persentasie motiliteit en progressiewe motiliteit by astenozoospermiese pasiënte verhoog. Onder hierdie laboratoriumtoestande het Pl3K-inhibisie nie die akrosoomreaksie beïnvloed nie, terwyl sperm-oosiet binding verhoog is. Hierdie resultate beteken dus dat PI3K spermmotiliteit en zona-binding negatief beïnvloed. In die laaste gedeelte van die studie is die effekte van intrasllulêre cGMP akkumulasie deur akute in vivo sildenafil sitraat (ViagraTM) toediening op seminale parameters, induksie van die akrosoomreaksie, sperm-oesiet binding en spermmotiliteit ondersoek. Soos verwag is geen veranderinge in die makro- en mikroskopiese seminale parameters deur sildenafil sitraat in vergelyking met plasebo veroorsaak nie. Verder is die akrosoomreaksies ook nie deur 50mg orale sildenafil sitraat geïnisieer of potensieer nie. Sperm-oosiet binding, geplaneerde snelheid, reguitlyn snelheid en persentasie vinnigbewegende selle was almal vehoog na sildenafil sitraat behandeling. Uit hierdie resultate blyk dit dat daar verskeie rolspelers in die zona pellucidageïnduseerde akrosoomreaksie is. 'n Deeglike insig van al hierdie seintransduksiepaaie en die onderlinge kruiskontak tussen mekaar sal uiteindelik die nodige inligting rakende die reseptore waaraan hierdie seintransduksie paaie gekoppel is, verskaf sowel as die intrasellulêre effektore wat uiteindelik spermfunksie beheer. Nog te meer sal die begrip van hierdie regulatoriese paaie verder noodsaaklik wees vir die toekomstige ontwikkeling van kliniese benaderings om bevrugting te bevorder of te voorkom.
32
Fernandes, Isabelle. "Etude fonctionnelle des protéines à domaine Zona Pellucida au cours de la morphogenèse épidermique embryonnaire chez la Drosophile". Toulouse 3, 2009. http://thesesups.ups-tlse.fr/767/.
Testo completoAbstract (sommario):
Le domaine Zona Pellucida (ZP) définit une famille de protéines membranaires conservées au cours de l'évolution. Cependant le rôle de ces protéines au cours du développement reste encore mal caractérisé. Par une approche génétique chez la drosophile, nous montrons qu'un ensemble de huit protéines ZPD est nécessaire à la réorganisation localisée du compartiment apical au cours de la morphogenèse épidermique embryonnaire. Malgré la conservation structurale des domaines ZP, ces protéines possèdent des fonctions spécifiques dans le remodelage de la forme apicale des cellules épidermiques. En effet, la perte de fonction de l'une des protéines ZPD ne peut être compensée par la surexpression d'une autre. Chacune de ces protéines se localise dans des régions distinctes du domaine apical ne se recouvrant que très partiellement. De plus, l'absence d'une protéine ZPD entraîne un détachement localisé entre la membrane et la matrice extracellulaire apicale (aECM). Ainsi, chacune de ces protéines s'accumule dans une sous-région distincte du compartiment apical, où elle va organiser des interactions entre la membrane apicale et l'aECM. Nous montrons que cet échafaudage de protéines ZPD est nécessaire pour sculpter la forme des extensions cellulaires et maintenir l'intégrité apicale des cellules qui vont les former. Les protéines ZPD révèlent une sous-compartimentalisation fonctionnelle de la membrane apicale, nécessaire au contrôle du changement de la forme des cellules épithéliales au cours du développementThe Zona Pellucida Domain (ZPD) defines a conserved family of membrane-anchored matrix proteins that are as yet poorly characterized with respect to their functions during development. Using genetic approaches in flies, we show here that a set of 8 ZPD proteins is required for the localized reorganization of embryonic epidermal cells during morphogenesis. Despite varying degrees of sequence conservation, these ZPD proteins exert specific and non-redundant functions in the remodeling of epidermal cell shape. Each one accumulates in restricted sub-regions of the apical compartment, where it organizes local interactions between the membrane and the extracellular matrix. In addition, ZPD proteins are required to sculpture the actin-rich cell extensions and maintain appropriate polarization of the apical compartment. These results on ZPD proteins therefore reveal a functional sub-compartmentalization of the apical membrane and its role in the polarized control of epithelial cell shape during development
33
Dietzel, Eileen [Verfasser]. "The biological role of fetuin-B : inhibition of zona pellucida hardening and preservation of female fertility in mice / Eileen Dietzel". Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2015. http://d-nb.info/1066813701/34.
Testo completo
34
Ström, Holst Bodil. "In vitro characterisation of cryopreserved canine spermatozoa : with special reference to post-thaw survival time and zona pellucida binding capacity /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5445-X.pdf.
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Petersen, Claudia Guilhermino [UNESP]. "Correlação da maturação e da morfologia do oócito humano com as características do fuso meiótico e da zona pelúcida". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/106388.
Testo completoAbstract (sommario):
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costa_cgpr_dr_botfm.pdf: 1744933 bytes, checksum: d90abe2ebd4b5e05246936b2f56031cd (MD5)Nas últimas décadas, alguns parâmetros laboratoriais têm sido propostos para identificar o potencial de saúde oocitária em Reprodução Assistida: 1. Maturidade nuclear e citoplasmática (pesquisa); 2. Dismorfismo (anomalias intracitoplasmáticas); 3. Fertilizaçao. Habitualmente, esses parâmetros (exceto a maturação citoplasmática) são avaliados pelo simples emprego de sistemas de microscopia de luz convencional. Nos últimos oito anos, foram relatados diversos estudos em oócitos humanos sobre a birrefringência da zona pelúcida (BF-ZP), a espessura da ZP, e a visualização do fuso meiótico (FM). Entretanto, ainda é discutível o poder desses novos parâmetros na seleção de óvulos com o pontecial de originar embriões com taxas de implantação elevadas, além disso, seu sistema de visualização e quantificação é complexo e dispendioso. O objetivo deste estudo foi investigar uma possível correlação entre esses parâmetros tradicionais com a BF-ZP, espessura da ZP e o FM. Dessa forma, um total de 73 pacientes que participaram do programa de injeção intracitoplasmática de espermatozóide (ICSI) no Centro de Reprodução Humana “Prof Franco Júnior” tiveram seus óvulos avaliados quanto a maturação nuclear (n=83), maturação citoplasmática (n=29), dismorfismo (n=280) e fertilização (n=216) sendo os resultados correlacionados com a imagem do FM (presença ou ausência), a intensidade da BF-ZP (positiva ou negativa) e a espessura da ZP. Os dados finais revelaram uma fraca correlação entre a maturação, o dismorfismo e a fertilização oocitária com a imagem do FM, a intensidade da BF-ZP, e a espessura da ZP. Entretanto, esses parâmetros poderiam ser responsáveis por identificar pontos biológicos diferentes do potencial de qualidade oocitária. Assim sendo, seria uma medida coerente, a utilização desses parâmetros, em forma conjunta, através de um escore de qualidade oocitária.
During the last decades, three laboratorial parameters have been proposed to identify the potential of the oocyte quality in ART: 1- Nuclear and cytoplasmic maturation; 2-Dysmorphims (intracytoplasmic abnormalities); 3 - Fertilization. These parameters (except the cytoplasmic maturation) are assessed by a simple system of conventional light microscopy. In the last eight years, numerous studies about zona pellucida birefringence (BF-ZP), zona pellucida thickness and meiotic spindle visualization have been reported. However, it is still controversial the power of these parameters in selecting oocyte with potential to develop into implantation-competent embryos. Furthermore, the microscopy system is complex and expensive. The present study aims to evaluate whether there is any correlation between the classical parameters with BF-ZP, ZP thickness and spindle image. A total of 73 patients who participated in an ICSI program had their oocytes evaluated such nuclear maturation (n=83), cytoplasmic maturation (n=29), dysmorphism (n=280) and fertilization (n=216) being its results correlated to the spindle image (presence or absence), BF-ZP intensity (positive or negative) and ZP thickness. The final results showed a low correlation between maturation, dysmorphism and fertilization compared to spindle image and ZP characteristics (BF-ZP, ZP thickness). However, these factors can be responsible to identify specific biological differ from the oocyte potential. Concluding, the use of these factors in association, as a score (oocyte quality score), could be the correct evaluation.
36
Safatli, Micheline. "Synthesis of neutral and acidic ß-O-linked glycoconjugates related to those found in the core structure of mammalian zona pellucida". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ36522.pdf.
Testo completo
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Grullón, Yunén Luis Alberto. "Función del sistema plasminógeno-plasmina en la fecundación de ovocitos bovinos y porcinos". Doctoral thesis, Universidad de Murcia, 2010. http://hdl.handle.net/10803/32113.
Testo completoAbstract (sommario):
El objetivo de este trabajo consistió en describir el papel del sistema plasminógeno/plasmina (PLG/PLA) en la fecundación bovina y porcina. Mediante fecundación in vitro, demostramos que la presencia de PLG ó PLA en el medio de coincubación de los gametos disminuía la penetración de los espermatozoides en los ovocitos y su unión a la zona pelúcida (ZP). Esta disminución no se debía a alteraciones de la funcionalidad espermática ni a cambios en la resistencia de la ZP a la proteolisis, sino a que la PLA provocaba la liberación de los espermatozoides adheridos a la ZP. Mediante inmunofluorescencia indirecta detectamos la presencia de PLG y sus activadores en la ZP y en el oolema de los ovocitos antes de la fecundación. Tras la fecundación, dicha presencia disminuyó o desapareció por completo, por lo que proponemos que el sistema PLG/PLA se activa durante la interacción espermatozoide-ovocito y contribuye a regular la polispermia.The aim of this study was to describe the role of the plasminogen/plasmin system (PLG/PLA) in bovine and porcine fertilization. Through in vitro fertilization, we demonstrated that the presence of PLG or PLA in the incubation medium of gametes decreased penetration of oocytes and sperm binding to the zona pellucida (ZP). This decrease was not due to alterations in sperm function or changes in the ZP resistance to proteolysis, but the PLA caused the release of sperm previously bound to the ZP. By indirect immunofluorescence we detected the presence of PLG and its activators in the ZP and oolema of the oocytes before fertilization. After fertilization, this presence diminished or disappeared completely, so we propose that the PLG/PLA system is activated during sperm-oocyte interaction and contributes to the regulation of polyspermy.
38
El-Mestrah, Majid Fouad. "Zona pellucida glycoproteins, structural topography and modifications of the carbohydrate determinants during folliculogenesis and following in vivo fertilization and in vitro egg activation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ59525.pdf.
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Hermansson, Ulrika. "Studies of canine and feline sperm viability under different storage procedures : with special reference to chilling, freezing, and use of zona pellucida binding assays /". Uppsala : Department of Clinical Sciences, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200668.pdf.
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40
Hanna, William F. "Sperm-zona pellucida interactions in the mouse evidence that Lewis X-containing neoglycoproteins mimic the intrinsic ability of ZP3 to induce the acrosome reaction /". Available to US Hopkins community, 2002. http://wwwlib.umi.com/dissertations/dlnow/3068781.
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41
Saucedo, Manuel Nicolas Verfasser], e Eckhard [Akademischer Betreuer] [Wolf. "Comparison between two vitrification methods for in vitro produced bovine embryos with an intact or a nonintact zona pellucida / Manuel Nicolas Saucedo. Betreuer: Eckhard Wolf". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2016. http://d-nb.info/1102157201/34.
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42
Bou, Khalil Maroun. "Biophysical and biochemical properties of the mammalian male germ cell specific sulfogalactosylglycerolipid (SGG): Contribution to the structure and zona pellucida affinity of pig sperm raft membranes". Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/29079.
Testo completoAbstract (sommario):
Raft membranes are implicated in cell adhesion. Here, we demonstrated that rafts isolated from hypermotile capacitated pig sperm as low-density Triton X-100 insoluble membranes had the ability to bind specifically to homologous zonae pellucidae (ZP). This binding was dependent on pig ZP3alpha sulfoglycoprotein, a major player in intact sperm binding. The male germ cell specific sulfogalactosylglycerolipid (SGG) was a sperm raft component and participated in sperm raft-ZP binding, since rafts pretreated with anti-SGG IgG/Fab had decreased ability to bind to the ZP dose dependently. SGG may also partake in raft formation. Fourier transform infrared (FTIR) spectroscopic studies of mixed SGG-cholesterol liposomes revealed that the sulfoglycolipid interacted with cholesterol (a significant raft component) via intermolecular hydrogen bonding. Moreover, mixtures of SGG and cholesterol were insoluble in 1--2% Triton X-100. Since cholesterol is significant for raft formation and since sperm capacitation is associated with cholesterol efflux, we determined whether raft levels in capacitated sperm were the same as those in control sperm. Interestingly, our results revealed an increase in raft levels in the capacitated sperm, as well as an enhanced ZP affinity of these membrane domains, compared to those of control sperm. These results corroborated the implication of rafts in cell adhesion and strongly suggested that the enhanced ZP-binding ability of capacitated sperm may be attributed to increased levels of sperm rafts, with a greater affinity for the ZP.
43
Zhang, Bing Rong. "Evaluation of frozen-thawed semen from Swedish Red and White AI bulls : with special reference to the relation between zona pellucida binding, in vitro fertilization and in vivo fertility /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1998. http://epsilon.slu.se/avh/1998/91-576-5436-0.gif.
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Bulgarelli, Daiane Lopes. "A vitrificação de oócitos bovinos prejudica sua capacidade reprodutiva, independente do estadio de maturação". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/17/17145/tde-10012017-115656/.
Testo completoAbstract (sommario):
Até o momento a literatura não determinou qual o melhor estadio de maturação (imaturo ou maduro) para que o oocito mantenha sua competência para o desenvolvimento reprodutivo após a criopreservação. O objetivo deste estudo foi determinar em qual estadio meiótico (imaturo -VG (vesícula germinativa) ou maduro- MII (metáfase II)) o oócito é menos susceptível ao dano na criopreservação, utilizando modelo experimental bovino. Foram utilizados ovários de vacas abatidas em matadouro, após a aspiração dos folículos, os oócitos imaturos (VG) foram selecionados para a maturação in vitro e vitrificação, e foram divididos em três grupos: 1) oócitos maturados in vitro e não submetidos à vitrificação (CONTROLE); 2) oócitos vitrificados imaturos (VG), descongelados e submetidos à maturação in vitro (CRIO-MIV); 3) oócitos maturados in vitro (MII), vitrificados e descongelados (MIV-CRIO). Os oócitos foram avaliados quanto a: a)maturação nuclear pela técnica de orceína acética; b) integridade da zona pelúcida (ZP) através de microscopia de polarização; c) viabilidade oocitária pela técnica de DEAD-LIVE; d) desenvolvimento embrionário (taxa de clivagem, produção e eclosão de blastocistos) através da fertilização in vitro (FIV) e ativação partenogenética (AT). Não houve diferença na capacidade de maturação nuclear entre os oócitos frescos e descongelados no grupo CRIO-MIV (p=0,23). Em relação à zona pelúcida a totalidade dos oócitos (100%) nos três grupos apresentou leitura de zona pelúcida positiva, não havendo correlação com evolução embrionária posterior. Na análise de viabilidade celular pelo DEAD-LIVE verificou-se que houve redução da viabilidade do grupo MIV-CRIO (27%) quando comparado com controle (84%) (p<0,0001). Na análise do potencial de desenvolvimento embrionário o grupo controle apresentou melhores taxas de clivagem após FIV (80%) e AT (58%), do que os grupos CRIO-MIV (28%; p<0,0001; 28%; p=0,0002, respectivamente) e MIV-CRIO (26%; p<0,0001; 22%, p<0,0001,respectivamente). As taxas de formação de blastocisto e eclosão após FIV nos grupos CRIO-MIV, MIV-CRIO e após AT no grupo MIV-CRIO foram nulas. Houve a produção e eclosão de apenas um blastocisto no grupo CRIO-MIV após AT. No modelo experimental utilizado, o procedimento de vitrificação comprometeu parcialmente a viabilidade dos oócitos medida pela técnica de DEAD- LIVE e completamente o desenvolvimento embrionário subseqüente, independente do estadio de maturação meiótica (VG ou MII) durante a criopreservação. No entanto, oócitos vitrificados em estadio de VG e submetidos à MIV foram meioticamente competentes e progrediram até o estadio de MII, sugerindo que o dano não compromete a capacidade de maturação nuclear do oócito. Este estudo não conseguiu determinar qual o melhor estadio meiótico oocitário para criopreservação, já que os dois estadios meióticos (VG e MII) se mostraram igualmente prejudicados pela criopreservação em relação à capacidade reprodutiva.Until the present literature has not achieved a consensus regarding the best maturation stage for oocyte to maintain their reproductive capacity after cryopreservation. The aim of this study was to determine, using an experimental bovine model, in which stage of development (VG stage, immature, or MII stage, post-maturation in vitro) the oocyte is less susceptible to damage during cryopreservation. Immature oocytes (VG) from the ovaries of slaughtered cows were selected for in vitro maturation or vitrification and divided into three groups. The first group (CONTROL) consisted of immature oocytes, matured in vitro without vitrification; the second group (CRYO-IVM) consisted of vitrified immature oocytes thawed and submitted to in vitro maturation; and the third group (IVM-CRYO) consisted of matured in vitro oocytes submitted to vitrification and thawing. The oocytes were evaluated for: nuclear maturation by acetic orcein staining; integrity of the zona pellucida using a polarized microscope; cell viability by the Dead-Live technique; and embryo development (cleavage, production and hatching rate) by in vitro fertilization and parthenogenetic activation. There was no difference in capacity of nuclear maturation between fresh and thawed oocytes (p=0.23). Regarding the zona pellucida (ZP), all oocytes (100%) of all three groups (control, CRYO-IVM and IVMCRYO) presented a positive ZP reading, with no correlation with later embryo evolution. DEAD-LIVE analysis of cell viability revealed reduction of viability in the IVM-CRYO group (27%) compared to control (84%) (p<0.0001) and to the CRYO-IVM group (56%) (p=0.017), with no difference between the last two groups (p=0.055). Analysis of the potential for embryo development by means of in vitro fertilization showed that the control group presented better cleavage and blastocyst formation rates than the CRYO-IVM (p<0.0001 and p<0.0001, respectively) and the IVM-CRYO (p<0.0001 and p=0.0004, respectively) groups. Analyzing the potential for embryo development the control group presented better cleavage by means of in vitro fertilization (80%) and parthenogenetic activation (58%) than the CRYOIVM (28%; p<0,0001; 28%; p=0,0002, respectively) and the IVM-CRYO groups (26%; p<0,0001; 22%, p<0,0001,respectively) Analysis of blastocyst formation rates and hatching after FIV and AT in CRYO-IVM and IVM-CRYO groups were null. Vitrification of bovine oocytes causes great impairment of their reproductive capacity regardless of the stage of maturation at the time of freezing. However the vitrified immature oocytes submitted to IVM maintained their capacity of nuclear maturation, as they achieved MII stage. This study was not able to determine which stage was better in reducing crio damage, as both stages (VG and MII) presented equally impaired by the process.
45
Cánovas, Bernabé Sebastián. "Interacciones homólogas y heterólogas in vitro de gametos porcinos, bovinos y humanos y sus aplicaciones en el estudio de la fecundación". Doctoral thesis, Universidad de Murcia, 2007. http://hdl.handle.net/10803/10851.
Testo completoAbstract (sommario):
La interacción entre gametos es crucial para la fecundación. La zona pelúcida (ZP) se considera responsable de bloquear la polispermia, pero in vitro estas funciones no son totalmente eficientes. La polispermia es frecuente en fecundación in vitro (FIV) en porcino y bovino, mientras que la interacción heteróloga espermatozoide-ovocito ha sido demostrada. Los objetivos fueron estudiar el bloqueo de la polispermia para mejorar los resultados de FIV e investigar las interacciones heterólogas entre espermatozoide humano y ovocito porcino. Los resultados demuestran que se produce endurecimiento de la ZP de ovocitos bovinos y porcinos de forma previa a la fecundación, utilizando DTSP o fluido oviductal bovino. Cuando se utilizan estos ovocitos en FIV aumenta la monospermia y el rendimiento final. En las interacciones heterólogas los espermatozoides humanos pueden unirse a ZP porcina y sufren la reacción acrosómica, pero no penetran los ovocitos sin ZP. En ICSI activan el ovocito y forman pronúcleos.The interaction between gametes is crucial to fertilization. The zona pellucida (ZP) is responsible to block of polyspermy, but in vitro these functions are not efficient. The polyspermy is frequently in bovine and porcine in vitro fecundation. Besides the heterologous interaction between spermatozoa-oocyte had been described. The aims were study the block of polyspermy to improve the output of IVF and research the heterologous interactions between human spermatozoa and porcine oocyte.The results show that there is hardening of bovine and porcine ZP previously at fertilization, in vivo and using DTSP or bovine oviductal fluid. When these oocytes are used in IVF improve the monospermy and the output. In heterologus interactions the human spermatozoa could bind to porcine ZP and it triggers the acrosome reaction, but not penetration in ZP-free oocyte was observed. In ICSI the oocyte activation and
46
Kongmanas, Kessiri. "Roles of Seminolipid and Its Associated Membrane Domain in Male Fertility". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32509.
Testo completoAbstract (sommario):
Our research aims at understanding the roles of seminolipid (sulfogalactosylglycerolipid or SGG) and its associated membrane domains in male reproduction. SGG is a sulfoglycolipid present selectively and abundantly in mammalian male germ cells. Therefore, information on its properties would be relevant towards the development of male fertility biomarkers and spermicide-based contraceptives. We have shown that SGG has direct affinity for zona pellucida (ZP, egg extracellular matrix) and plays a role in the formation of sperm lipid rafts, the ZP-binding platforms on the sperm anterior head plasma membrane (APM), the initial ZP binding site. For a better understanding of mechanisms underlying sperm-ZP interaction, I performed proteomic characterization of APM vesicles (SGG-associated membrane domains with ZP affinity) isolated from sperm before and after capacitation, a process through which sperm gain maximal ZP affinity. Proteomic results revealed that capacitated APM vesicles contained high-molecular-weight protein complexes, with higher ZP affinity and levels of ZP-binding proteins as compared with those of the non-capacitated samples. ZP-binding proteins known to exist in the acrosome (i.e., zonadhesin, proacrosin/acrosin) were found in these APM protein complexes. Immunofluorescence suggested that a fraction of these proteins trafficked from the acrosome to APM during capacitation. These findings provided a new mechanism on how sperm gain full ZP-binding ability during capacitation. Since SGG is a major component of APM, proper SGG levels at this site would be important for male fertility. Levels of sperm SGG are regulated through the synthesis and degradation. In fact, lack of SGG-synthesis enzymes causes a spermatogenesis disruption, resulting in male infertility. However, significance of SGG degradation remains unknown. SGG can be desulfated in vitro by arylsulfatase A (ARSA), an enzyme existing in the acrosomes of sperm/spermatids and lysosomes of Sertoli cells, testicular somatic cells that nurture developing germ cells. Sertoli cells also phagocytose ~50% of germ cells that become apoptotic during spermatogenesis. To understand physiological importance of SGG degradation, the fertility status and SGG levels of Arsa-/- male mice were determined. We found that Arsa-/- males became subfertile when they were older than 5 months, and when they were 8-month-old (~40-year-old men) they produced sperm at 50% wild type rate. Arsa-/- sperm had minimal in vitro fertilizing ability and a number of them showed abnormal morphology. Quantitative mass spectrometry revealed that SGG levels in Sertoli cells of 8-month-old Arsa-/- mice were increased to ~250% of the wild type level; this SGG accumulation may lead to a decrease in Sertoli cell ability to support spermatogenesis. However, SGG levels in sperm of 8-month-old Arsa-/- mice were ~50% of the wild type value, a result that partly explained the decreased fertilizing ability of these sperm. The reduced SGG level of Arsa-/- sperm was likely due to a lack of SGG’s building-block lipid (palmitylpalmitoylglycerol) putatively generated in Arsa-/- Sertoli cells and recycled to the next generation of primary spermatocytes for SGG synthesis. Hence, levels of sperm SGG are a promising bioindex for male fertility. Since Sertoli cells also regulate SGG homeostasis, their functionality should be now included in male fertility/subfertility diagnosis.
47
Mazzeo, Ilaria. "Effect of thermal regime on the expression of key reproductive genes during hormonally-induced vitellogenesis in female European eels". Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/48490.
Testo completoAbstract (sommario):
European eel (Anguilla anguilla, L., 1758) is suffering a strong
population decrease and at the same time it is a very appreciated
species and by now it has not been possible closing its cycle life. In
fact, this species does not mature in captivity unless hormonally
induced. So all the production is up to the natural population. All
these factors together make urgent achieving the closing of the
productive cycle and for this aim it is important to understand the
reproductive physiology and the reasons of this development
blockage.
The present thesis wants to be a new contribution to the knowledge
of reproductive physiology in female European eel submitted at
hormonal treatment. To achieve this goal, expression of genes not
previously studied in this species (cyp19a1, ara, arb, gnrhr1a,
gnrhr1b, gnrhr2, zpb and zpc) was analyzed in eels reared under a
constant thermal regime, accordingly to the usual rearing
conditions. Also, the effect of rearing temperature on gene
expression and steroid profile (T, 11-KT and E2) was studied. In
fact, eels migrate to Sargasso Sea to reproduce and during the
travel experiment temperature changes, while traditionally they are
reared at a constant high temperature which could affect
vitellogenesis progression and final oocyte quality.
For the study it was necessary cloning and characterizing some
genes which have not still been sequenced in European eel. Gene
expression was studied by qPCR after designing primer and
optimizing the qPCR race. Steroid profiles were analyzed by
immunoassays and the gonadal development stages were
established by histology.
The first result obtained at the end of the study were six new genes
characterized in European eel.
The analysis of gene expression allowed to understand the
involvement of specific genes during vitellogenesis (arb, gnrhr1b
and gnrhr2) in different brain regions.
The temperature was conformed as a crucial environmental factor
affecting vitellogenesis. On one hand, eels matured at lower starting
temperatures showed better reproductive parameters which could
have an influence in the final oocyte quality. On the other hand
higher temperatures are necessary to achieve further vitellogenetic
stagesMazzeo, I. (2014). Effect of thermal regime on the expression of key reproductive genes during hormonally-induced vitellogenesis in female European eels [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48490
TESIS
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Busca, Cláudia Sofia Nunes. "Analysis of the role of ZP3 and APP in cell-cell adhesion". Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/12945.
Testo completoAbstract (sommario):
Mestrado em Biomedicina MoleculaAmong different types of cell-cell interactions present in the body, the interaction between the oocyte and a sperm cell is of great importance for species perpetuation. Cellular adhesion is thus a crucial process in fertilization, which involves the oocyte’s zona pellucida (ZP), the first barrier found by sperm cells that mediates the first contact between gametes. ZP3 is a major ZP glycoprotein of the oocyte, and its ligand in sperm cells is still unknown. The APP glycoprotein was found by us to be in the sperm’s head, including its equatorial zone involved in sperm-oocyte interaction. This protein plays a role in the pathogenesis of the Alzheimer’s disease and its physiologic roles are still being unravelled. The present work aimed to characterize a putative APP-ZP3 interaction in cell-cell adhesion. Relevant functional motifs on the ZP3 amino acid sequence were analysed, and the role of ZP3 and APP in cell-cell adhesion was evaluated. Interference assays were performed with antibodies against epitopes of APP, ZP3 and β1-integrin, the latter an important protein in cellular adhesion known to bind APP. The subcellular co-localization of ZP3 and APP was analysed by immunocytochemistry assays, and a potential physical interaction between ZP3 and APP was evaluated by immunoprecipitation. Results indicate that, from the studied proteins, APP and β1-integrin are the most important in cell-cell adhesion, probably through a common pathway. ZP3 has only a minor effect in cell-cell adhesion, but is able to interfere with adhesion mediated by APP and β1-integrin, potentially sharing their common pathway. Surprisingly, ZP3 and APP only co-localize at low quantities in vesicles, mainly near the Golgi apparatus, while there is a slightly higher degree of co-localization between ZP3 and β1-integrin near the plasma membrane. Unexpectedly though, ZP3 and APP were found to co-localize in extracellular aggregates of secreted ZP3. Immunoprecipitation results so far further suggest that highly glycosylated ZP3 and APP forms physically interact, what may reflect an important interaction between these proteins in the oocyte’s ZP upon fertilization.
Entre os diversos tipos de interações entre células que ocorrem no organismo, a interação entre o oócito e o espermatozoide é de grande importância para a perpetuação da espécie. A adesão celular é então um processo fundamental para a fertilização, a qual envolve a zona pelúcida (ZP) dos oócitos, a primeira barreira encontrada pelos espermatozoides que medeia a primeira interação entre os gâmetas. A ZP3 é uma das principais proteínas da ZP, e ainda não se conhece qual o seu ligando no espermatozoide. A glicoproteína APP foi descrita por nós como estando presente na cabeça do espermatozoide, em particular na zona equatorial, envolvida na interação espermatozoide-oócito. Esta proteína é central à patogénese da Doença de Alzheimer e os seus papéis fisiológicos ainda não estão bem caracterizados. Este trabalho focou-se na caracterização de um possível interação entre a APP e a ZP3 na adesão célula-célula. Foi realizado um levantamento de motivos funcionais relevantes no ZP3, e avaliado o papel deste e da APP na adesão célula-célula. Para tal foram realizados ensaios de interferência com anticorpos contra epitopos da APP, da ZP3, e também da β1-integrina, um proteína importante na adesão celular e que se sabe ligar à APP. A co-localização subcelular entre a ZP3 e a APP foi analisada por imunocitoquímica, e uma possível interação física entre a ZP3 e APP monitorizada através de ensaios de imunoprecipitação. Os resultados indicam que, de entre as proteínas estudadas, a APP e a β1-integrina são as mais importantes na adesão celular, provavelmente através de uma via comum. A ZP3 parece ter apenas um pequeno efeito na adesão célula-célula, possivelmente através da mesma via da APP e da β1-integrina. Surpreendentemente, ZP3 e APP apresentam pouca co-localização, e especialmente em vesiculas perto do complexo de Golgi. Contudo, existe um maior grau de co-localização entre a ZP3 e a β1-integrina, particularmente perto da membrana plasmática. Inesperada foi também a presença de agregados extracelulares de ZP3 secretada contendo também APP. Os resultados preliminares dos ensaios de imunoprecipitação sugerem uma interacção física entre as formas altamente glicosiladas da APP e da ZP3, o que pode refletir uma importante interação destas duas proteínas na ZP do oócito aquando da fertilização.
49
LUCAS, HERVE. "La zone pellucide : etude des oligosaccharides dans deux especes animales et chez l'homme". Angers, 1993. http://www.theses.fr/1993ANGE1130.
Testo completo
50
Bercegeay, Sylvain. "Contribution a l'etude de la zone pellucide de l'ovocyte : composition et modification au cours du processus de fecondation". Nantes, 1995. http://www.theses.fr/1995NANT01VS.
Testo completo