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Endocrine correlates of free-ranging African elephant (Loxodonta africana) treated with porcine zona pellucida vaccineBates, Melodie Joy 04 January 2011 (has links)
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
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Phage Display to Identify Peptides Binding to or Penetrating the Mouse Zona PellucidaLowe, Jeanette 11 July 1999 (has links)
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
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Identifikation antigener Determinanten des ZPB2 Proteins der Hauskatze und Charakterisierung ihrer kontrazeptiven und immunogenen EigenschaftenRingleb, Jennifer January 2004 (has links)
Die immunologische Kontrazeption mittels Zona pellucida (ZP) Proteinen gilt als vielversprechender Ansatz für die Reproduktionskontrolle verwilderter Haus- und Wildtierbestände. Da die Applikation von nativer ZP mit Nebenwirkungen verbunden ist, wird die Verwendung einzelner ZP Peptide als Bestandteil kontrazeptiver Vakzine als besonders aussichtsreich erachtet. Das Prinzip dieser nebenwirkungsfreien ZP Immunisierung ist die gezielte Trennung der Entzündungsreaktionen auslösenden T-Zell-Epitope der ZP von den kontrazeptiv wirkenden B-Zell-Epitopen.<br>
Niedermolekulare synthetische oder rekombinante Peptide allein sind gering immunogen und können somit keine ausreichende Immunantwort induzieren. Die Verwendung von Peptiden für die immunologische Kontrazeption erfordert daher ein „Vakzin-Design“, d. h. die gezielte Kombination der Peptide mit immunstimulierenden Substanzen (Liposomen, Carrierproteinen, Adjuvantien).
Zielstellung der vorliegenden Arbeit war die Untersuchung des Potentials synthetischer Peptide für die Immunokontrazeption von verwilderten Hauskatzen (Felis catus). Dazu wurden zunächst relevante B-Zell-Epitope des felinen Zona pellucida Proteins, ZPB2, identifiziert und synthetisiert. Zwei der synthetischen Peptide (P3, P6) wurden zur Herstellung von Antikörpern an BSA konjugiert und zusammen mit Freundschem Adjuvans in Ratten verimpft. Die kontrazeptive Relevanz beider Peptide sowie der Ratten Anti-Peptid Antiseren wurde im in vitro Befruchtungssystem der Hauskatze geprüft. Zur Untersuchung der Immunogenität der Peptide in der Zielspezies Hauskatze erfolgte die Entwicklung von Vakzin-Prototypen für die einmalige Applikation. Neben der Eruierung der Stärke und Dauer der Immunantwort wurde durch Verpaarung der Tiere auch das kontrazeptive Potential in vivo abgeschätzt. / Immunological contraception based on zona pellucida (ZP) proteins is regarded as a promising approach for the control of reproduction in feral domestic and wild animals. Because application of native ZP caused adverse reactions, utilization of single ZP peptides as elements of contraceptive vaccines were considered to bear good prospects. The principle of this ZP immunization is based upon a systematic separation of inflammation triggering T-cell epitopes from the contraceptive B-cell epitopes.<br>
The present study evaluates the immunogenicity and contraceptive potential of synthetic feline ZPB2 peptides for immunocontraception in cats (Felis catus).
First of all, relevant B-cell epitopes were identified and synthesized. In order to generate antipeptide antibodies two peptides (P3, P6) were chosen and coupled to BSA. Rats were immunized with the conjugation product combined with Freund′s complete adjuvant.<br>
The contraceptive efficacy of both peptides and of the anti-peptide antibodies generated were determined using in vitro fertilization of feline oocytes (IVF). To evaluate the peptides immunogenicity in the target species (cat), vaccine-prototypes were developed for a single application protocol. The strength and duration of the immune response was analyzed. Additionally, cats were mated to assess the contraceptive potential of the vaccines in vivo.
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The effect of solubilized homologous zona pellucida on the human acrosome reaction, sperm-zona binding and motion characteristics of capacitated human spermatozoaBastiaan, Hadley Saville 12 1900 (has links)
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.
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Model-based simulations of the piercing process in piezo-ICSIGan, Yong, Chen, Zhen, January 2008 (has links)
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.
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Biochemické parametry zony pellucidy prasečích oocytů během folikulogenezeVildová, Denisa January 2014 (has links)
Polyspermic fertilization is one of major problems during in vitro fertilization of porcine oocytes. Zona pellucida is an extracellular matrix, that surrounds growing mammalian eggs and is responsible for polyspermy block after fertilization. Porcine zona pellucida is composed of three glycoproteins called ZP2, ZP3 and ZP4. This study is aimed to modifications of ZP3 protein of oocytes with different developmental competence. No significant differences were found in expression of ZP3 protein in oocytes with lower developmental competence (follicular size S), in compared to oocytes with higher developmental competence (follicular size M). However, it was found significant differences in acidification of ZP3 protein of immature oocytes removed from follicles of size S, in compared to oocytes removed from follicles of size M. Moreover, using Western blot analysis, it was detected band in area > 50 kDa, which could play an essential role during fertilization of oocytes.
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Correlação da maturação e da morfologia do oócito humano com as características do fuso meiótico e da zona pelúcida /Petersen, Claudia Guilhermino. January 2009 (has links)
Orientador: José Gonçalves Franco Júnior / Banca: 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
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Studium proteinů spermií různých savčích druhů / Study of sperm proteins in different mammalian speciesPohlová, Alžběta January 2016 (has links)
Reproduction is an essential feature of all animals and a fundamental step to produce new generations. Study of sperm proteins is crucial for understanding of the sperm-egg recognition. We searched out sperm surface proteins involving in the zona pellucida (ZP) binding and studied whether these proteins are preserved throughout mammalian species. Indirect immunofluorescent technique was used to test a panel of monoclonal antibodies prepared against boar sperm surface proteins on spermatozoa of bull and mice. We found a cross-reactivity of some antibodies against boar sperm with bull ejaculated and mouse epididymal spermatozoa. Further, we isolated sperm proteins from different mammalian species, such as pig, bull, dog, cat, mouse and human. Proteins were separated by SDS- electrophoresis and protein/glycoprotein profiles from epididymal, ejaculated and in vitro capacitated sperm were compared. The interaction of sperm with ZP was studied on electrophoretically-separated sperm surface proteins from pig and bull with biotin-labeled ZP glycoproteins. Antibodies, which reacted with boar sperm surface proteins with ZP- binding activity, therefore could be potential egg-binding receptors, were used for monitoring of the sperm protein origin in reproductive fluids and tissues. (In Czech) Keywords: sperm...
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Molecular evolution of the carboxy terminal, the putative sperm-ZP binding site, of the zona pellucida 3 glycoprotein in old world murine rodents.Swann, Christine A. January 2007 (has links)
In mammals, before fertilisation can occur, sperm have to bind to, and penetrate, the extracellular coat of the oocyte, the zona pellucida (ZP). In the laboratory mouse, which has been used as a model system for fertilization studies, sperm-ZP binding has been found to be mediated by a region near the carboxy terminal, encoded by exon 7 of the Zp3 gene. This region shows considerable interspecific sequence diversity in North American cricetid rodents, with some evidence of adaptive evolution, suggesting that this may contribute to species specific sperm-ZP binding. However, by contrast, in a preliminary study of three species of Australian murine rodents an identical protein sequence of the region encoded by exon 7 of Zp3 was found to be present. The aim of this present study was to determine the pattern of sequence diversity of this region in the most speciose subfamily of mammals, the murine rodents, and to obtain insight into the selective pressures involved in its evolution. For this, DNA was extracted from murine rodents of Africa, Eurasia, South-east Asia, New Guinea and Australia. The nucleotide and predicted amino acid sequence of exons 6 and 7 of Zp3 in 96 murine species from 14 divisions, as recently defined by Musser and Carleton (2005), was determined and compared. Generally, it was found that closely related species shared a highly similar ZP3 sequence. Maximum likelihood analyses of codon substitution models using representatives from 14 murine divisions, suggested that positive selection had occurred within only a few lineages at several different codon sites adjacent to, or within, the putative combining-site for sperm of ZP3. Positive selection was not evident when the analysis was restricted to the Australian taxa which showed low levels of both intra- and inter-generic sequence divergence. There was no good evidence that this region contributes to species specificity of sperm-ZP binding in these species. These findings thus suggest that the selective forces acting on the Zp3 exon 7 region during the evolution of the murine rodents have varied possibly due to a range of selective pressures not necessarily restricted to the prevention of hybridization. It seems unlikely, therefore, that the amino acid sequence of the exon 7 coding region contributes to species specificity of sperm-ZP binding within most of the lineages from this most speciose subfamily of eutherian mammals. / http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1294654 / Thesis(Ph.D.)-- School of Medical Sciences, 2007
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Izolace a studium proteinů se zona pellucida vazebnou aktivitou / Isolation and study of proteins with zona pellucida binding activityZigo, Michal January 2014 (has links)
Binding of sperm to the oocyte is mediated by complementary molecules on the surface of both gametes and involves the interaction of sperm protein receptors with the zona pellucida (ZP) saccharide structures. It has been shown that many proteins receptors are involved in the sperm-ZP interaction, and potential primary sperm receptors for ZP glycoproteins have been investigated in various mammals. The majority of proteins with identified sperm-ZP binding activity belong to the plasma membrane proteins. However, the exact methods for isolation of sperm membrane proteins are still to be standardized. This study is focused on investigating how employment of various isolation protocols leads to acquisition of various protein mixtures. Further in the work, two possible approaches towards identification of potential ZP-binding partners are implemented, in order to disclose novel primary ZP-binding receptor candidates. Sperm proteins of ejaculated and in vitro capacitated boar sperms were isolated by: Triton X-100, Triton X-114, acetic acid, sodium dodecyl sulphate (SDS), N-octyl-β-D- glucopyranoside (OBG), rehydration buffer (RHB), and finally by freezing-thawing extraction and they were characterized by 1-D, 2-D protein profiles, glycoprotein staining and substrate zymographic methods. The results have...
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