Dissertations / Theses: 'Zygoma'

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Ventín, Palacín Ramón. "Tratamiento de la enfermedad periodontal severa con Zigoma Quad en un solo tiempo quirúrgico, bajo carga inmediata y evaluación de la calidad de vida asociada." Doctoral thesis, Universitat de Lleida, 2019. http://hdl.handle.net/10803/667900.

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Objectius: El propòsit d'aquest estudi és quantificar l'impacte en la qualitat de vida de pacients amb periodontitis avançades, sotmesos a rehabilitació de maxil•lar superior amb quatre implants zigomàtics, sota un protocol de càrrega quirúrgica immediata i en un sol temps quirúrgic amb anestèsia local i sedació conscient. Material i mètodes: seixanta-quatre pacients edèntuls i parcialment edèntuls de maxil•lar superior són sotmesos a un tractament amb quatre implants zigomàtics per pacient, (n = 256 Implants) sent avaluada la qualitat de vida associada a la salut bucodental abans i sis mesos després del tractament, per posteriorment ser controlats clínicament durant un període mitjà de seguiment de 7,6 anys oscil•lant entre 13 anys el màxim fins a 1 any i 3 mesos el mínim. Resultats: les puntuacions del test OHIP-14 varien d'una manera estadísticament significativa amb una p <0.001después del tractament. El seguiment clínic revela un èxit del tractament del 100% durant el període d'estudi, amb un èxit protèsic del 83,5%, una taxa de supervivència dels implants de 96,5% i amb un 5% de fístula cutània peri orbitària. No s'ha registrat cap sinusitis maxil•lar durant el període d'estudi. Conclusions: La implantología transcigomática amb reposició de les dents residuals condiciona un increment en la qualitat de vida referida a la salut bucodental respecte al conservacionisme periodontal tradicional del tractament de la malaltia periodontal severa.
Objetivos: El propósito del presente estudio es cuantificar el impacto en la calidad de vida de pacientes con periodontitis avanzadas, sometidos a rehabilitación de maxilar superior con cuatro implantes zigomáticos, bajo un protocolo de carga quirúrgica inmediata y en un solo tiempo quirúrgico con anestesia local y sedación consciente. Material y métodos: sesenta y cuatro pacientes edéntulos y parcialmente edéntulos de maxilar superior son sometidos a un tratamiento con cuatro implantes cigomáticos por paciente, (n=256 Implantes) siendo evaluada la calidad de vida asociada a la salud bucodental antes y seis meses después del tratamiento, para posteriormente ser controlados clínicamente durante un período medio de seguimiento de 7,6 años oscilando entre 13 años el máximo hasta 1 año y 3 meses el mínimo. Resultados: las puntuaciones del test OHIP-14 varían de un modo estadísticamente significativo con una p<0.001después del tratamiento. El seguimiento clínico revela un éxito del tratamiento del 100% durante el período de estudio, con un éxito protésico del 83,5%, una tasa de supervivencia de los implantes de 96,5 % y con un 5% de fístula cutánea peri orbitaria. No se ha registrado ninguna sinusitis maxilar durante el período de estudio. Conclusiones: La implantología transcigomática con reposición de los dientes residuales condiciona un incremento en la calidad de vida referida a la salud bucodental respecto al conservacionismo periodontal tradicional del tratamiento de la enfermedad periodontal severa.
Objectives: The purpose of the present study is to quantify the impact in the quality of life in patients with advanced periodontitis, undergoing a full rehabilitation of the maxilla with four zygomatic implants, and an immediate-loading protocol. All carried out in a single stage and with the use of local anesthesia in a single surgical time with local anesthesia and conscious sedation only. Material and methods: four zygomatic implants were placed in each of the 64 edentulous and partially edentulous patients included in the study. The quality of life was monitored before and six months after treatment. After this time, they were assessed clinically with a mean follow-up period of 7,6 years ( from 15 months minimum up to 13 years). Results: The difference among the results obtained from OHIP test is statistically significant ( p<0,001) after the treatment. The follow-up has clearly shown a 100% of success rates at implant placement with an 83,5% of prosthetic success rates. The implant survival rates were 97,5% during the study, with a 5% of skin periorbital fistula. No maxillary sinusitis was reported during the study. Conclusions: Inmediately loaded zygomatic implants have been shown to considerably increase the oral quality of life of the patient in contrast to the conservative treatment of the advanced periodontal disease .

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Muller, Samantha. "Shape analysis of the zygoma to assess ancestry and sex variation in modern South Africans." Diss., University of Pretoria, 2021. http://hdl.handle.net/2263/78395.

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Skeletal remains exposed to an outdoor context are prone to post-mortem damage and fragmentation, making skeletal analysis difficult for the anthropologist. Research on ancestry and sex from isolated fragments of the cranium is necessary to improve identification of fragmented remains. The zygoma has proven to be more durable post skeletonization than other cranial bones, making research relevant into variation within the zygoma. Whilst the shape of the zygoma has been studied in a South African population using morphological, metric and geometric morphometric techniques, these studies did not include Indian South Africans. The Indian South African population comprises 2.6% of the total population but make up a larger proportion of the population in certain areas. For example, Indian South Africans comprise 7.4% of the population in Kwa-Zulu Natal and 2.9% in Gauteng. More specifically, Indian South Africans make up to 60% of the population in the suburb of Chatsworth with a further 91% of the population in sub-area of Arena Park, and 80% of the population in the Laudium suburb of Gauteng. Therefore, Indian South Africans must be included in anthropological studies attempting ancestry classifications. The purpose of the study was to assess the shape variation and projection of the zygoma attributable to sexual dimorphism and ancestral variation among South Africans, including Indian South Africans, using a geometric morphometric approach. A sample of 400 three-dimensionally (3D) reconstructed models from head CT scans of black, coloured, white, and Indian South Africans were used with an equal sex and ancestry distribution. Eleven landmarks previously described in the literature were used for the analysis. Each landmark was used to depict the most prominent points on the outline of the zygoma. Additionally, semi-landmarks were placed along the curves of the zygoma. The landmarks and semi-landmarks were tested for observer repeatability and reliability using dispersion analysis and revealed that all landmarks were repeatable. Procrustes ANOVA revealed significant differences among the population groups and between the sexes for all population groups, except between coloured South African males and females. A pairwise post-hoc test revealed that white and Indian South Africans had the most similarities except for males, where coloured and Indian South Africans had the most similarities for landmarks. Three interlandmark distances were created to assess the zygoma’s projection. The ANOVA for the projection of the zygoma revealed significant differences for both sex and ancestry except for white South African males and females and males overall for the zygomaticomaxillary length. The zygomaticomaxillary length (ZML) is defined as the maximum distance between the landmarks zygoorbitale and zygomaxilare. No significant differences were noted for female South Africans for the Superior Zygomatic Length which, is a measure of the maximum length of the superior margin of the zygoma (between porion and zygoorbitale; PorZygool). Further analysis of the zygoma’s projection involved creating angles between the interlandmark distances. The ANOVA for the angles of projection revealed significant differences between sexes and populations, except for white and Indian South African males and females at Angle1 (Angle at the intersection of ZML and PorZygoml) and Angle3 (the angle at the intersection of PorZygool and PorZygoml) and black, coloured and Indian South African males and females at Angle2 (the angle at the intersection of ZML and PorZygool). The large amount of overlap amongst ancestry groups demonstrated substantial group similarities; however, differences were noted at the zygomaxillary, zygomaticotemporal and frontomalar sutures. Overlap was also present between males and females, but on average, males were larger than females. Differences, such as a more inferior placement of the zygoorbitale landmark were noted at the inferior margin of the orbit specifically in females. Differences were also noted at the inferior margin of the orbit across all groups. Discriminant functions were created to assess the classifying ability of the shape of the zygoma. Results revealed low accuracies for ancestry classification for the shape and projection of the zygoma. However, higher accuracies were noted for sex classification for the shape and projection of the zygoma. While results demonstrate shape variation of the zygoma, the classifying ability of the zygoma is precarious at best, and the use of the zygoma in a forensic context may not be an option. However, the differences observed can be taken into consideration during medical procedures such as zygomatic and infraorbital implants. Although landmark placements were reliable and repeatable, further analysis of the zygoma using a semi-automatic surface registration method along with different imaging techniques (MicroCT and CBCT scans) may assist in the data collection procedure and may potentially increase the accuracy of the results. Furthermore, the results of the current study highlight the need for the assessment of the effects of diet, climate, age, edentulism and symmetry on the shape of the zygoma.
Dissertation (MSc (Anatomy))--University of Pretoria, 2020.
National Research Foundation (NRF)
Anatomy
MSc (Anatomy)
Unrestricted

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Tawha, Tafadzwa Primrose Rudo. "Assessing the accuracy of the zygoma for estimating ancestry using geometric morphometrics in a South African sample." Master's thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/31282.

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The large number of unidentified, decomposed and skeletonised remains found in South Africa (SA) necessitates relevant and reliable methods to assist in victim identification. Ancestry estimation from unknown skeletal remains is essential when reconstructing a demographic profile of a missing person. In the SA population, estimating ancestry is problematic as standards developed internationally rarely apply to the local, biologically heterogenous population. Craniofacial morphology is known to be ancestrally distinct and studies are yet to explore shape and size variation in the zygomatic bone of the SA population. The aim of this study was to assess ancestral variation in zygomatic shape and size in a SA population using three-dimensional geometric morphometric analyses. A sample of 158 individuals were analysed from Bantu-speaking (BA), European (EA) and Mixed Ancestral (MA) South African groups. Males were larger in size than females, but no size differences were observed between ancestral groups. Significant shape differences were observed between ancestral groups, while none were observed between males and females. BA and MA individuals had narrower, shorter and more anteriorly projecting zygomas than EA individuals. The zygoma was shown to accurately distinguish EA (84%) from BA (81%), and MA (80%) from EA (68%) individuals, but unreliably distinguished BA (60%) from MA (66%) individuals. This is likely correlated to the historical peopling of SA and historical forced racial classification. Age-related changes and antemortem tooth loss did not confound the ancestral variation in size, despite minor changes in zygomatic shape being associated with these two factors. These confounders did not impact ancestry estimation accuracies, further suggesting a minor impact on overall zygomatic shape. Furthermore, the patterning of ancestral variation in the zygoma revealed the need for further research to distinguish between the biologically heterogenous ancestral groups in SA.

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Bertos, Quílez Jorge. "Evaluación del volumen óseo malar ocupado por un implante cigomático y su trayecto en función del grado de atrofia ósea alveolar en la técnica de zygoma quad: Un estudio tridimensional mediante CBCT." Doctoral thesis, Universitat Internacional de Catalunya, 2017. http://hdl.handle.net/10803/440534.

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El objetivo principal de este estudio fue investigar virtualmente el volumen de hueso que un implante cigomático ocupa en el hueso cigomático según los distintos grados 4 y 5 de atrofia aleolar de Cawood y Howell. Los objetivos secundarios fueron investigar virtualmente :el trayecto de un implante cigomático, la altura residual al suelo del seno maxilar y suelo de cavidad nasal, la angulación vestíbulo-palatina de un implante cigomático respecto al plano medio-sagital, la angulación mesio-distal de un implante cigomático respecto al plano frontal, la longitud de la muestra de los implantes cigomáticos, la longitud intramalar del implante cigomático, la densidad del hueso malar en el área del implante cigomático en función de los diferentes grados de atrofia ósea alveolar de Cawood y Howell. Se llevó a cabo una evaluación tridimensional de 23 CBCT mediante la máquina de escáner de haz de cono i-CAT Cone Beam 3D imaging (Imaging Science International, Inc., Hatfield, USA) de cuatro implantes cigomáticos o “Zygoma Quad” colocados virtualmente mediante el software Simplant pro.16 (Dentsply. Sirona. Iberia) en aquellos casos de maxilares superiores totalmente edéntulos con atrofias óseas de Cawood y Howell grado 4 y 5 propias de la pérdida de dientes y no de las derivadas de traumatismos maxilofaciales o cirugías resectivas oncológicas del territorio maxilofacial. Los CBCT eran correspondientes a 23 pacientes de la base de datos de la Universidad Internacional de Catalunya e Instituto Maxilofacial del Centro Médico Teknon realizados En una muestra de 92 implantes zigomáticos, el volumen malar de hueso medio ocupado fue de 0,19 ± 0,06 cc., siendo invariable a la tipología de atrofia que presenta la posición a tratar (p=0,650). El 60,9% de los implantes tenía un trayecto extrasinusal, 25% un trayecto parasinusal y el restante 14,1% un trayecto intrasinusal, observando cómo a medida que el grado de atrofia ósea alveolar aumenta, el implante se relaciona más con el seno maxilar adquiriendo trayectos parasinusales e intrasinusales y a medida que las alturas óseas residuales al suelo del seno maxilar y suelo de nariz aumentaban, la relación del implante con el seno maxilar adquiría trayectos más extrasinusales. El ángulo vestíbulo-lingual medio respecto al plano sagital fue de 47,2 ± 7,5º siendo significativamente superior en posiciones con atrofia más importante, tanto globalmente (p<0,001), como en sector anterior (p<0,001) o posterior (p=0,001). El ángulo mesio-distal medio respecto al plano coronal fue de 37,3 ± 12,5º, siendo significativamente superior en posiciones con atrofia más importante sólo en el sector anterior (p=0,021). La longitud media de los implantes colocados fue de 45,7 ± 5,8 mm, y esta varió según su posición (en sectores anteriores los implantes son de mayor longitud que en sectores posteriores) y atrofia ósea (a mayor grado de atrofia menor longitud de implante colocado). La longitud intra-malar media fue de 16,9 ± 4,7 mm, siendo superior en posiciones con atrofia de grado 4 respecto a grado 5, pero sólo se alcanzó la significatividad estadística en el sector posterior (p=0,028) y en la muestra global (p=0,011). La densidad malar ósea media relacionada con la porción de implante cigomático alojada en el hueso malar fue de 515,6 ± 212,6 UH, siendo mayor en casos con atrofia de grado 4 en el total de la muestra, al límite de la significancia (p=0,054). Los resultados sugieren que el volumen medio del hueso malar ocupado por un implante cigomático es invariable sin importar la posición del implante y el grado de atrofia ósea alveolar y a medida que la atrofia alveolar aumenta, el trayecto del implante se vuelve más parasinusal e intrasinusal. En todos los casos los examinadores encontraron suficiente hueso para distribuir adecuadamente los implantes.

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Jardine, Brittany A. "Differential diagnoses of temporal bone defects and zygomatic bone lesions found in fetal and infant individuals from the Kellis 2 cemetery, Dakhleh Oasis, Egypt." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4777.

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The Kellis 2 cemetery site within the Dakhleh Oasis, Egypt provides a unique study opportunity due to the large number of infant, perinatal, and fetal individuals that have been recovered. Several of the infant and fetal remains have undiagnosed circular defects on the temporal bone, and others have undiagnosed lesions on the zygomatic bone. Of the 268 individuals under one year of age that have been analyzed from the Kellis 2 cemetery, twenty-six individuals have the temporal bone defect and six have the zygomatic bone lesions. A survey of clinical and paleopathological research provided possible pathological conditions that could cause abnormalities such as defects or lesions on the temporal bones or zygomatic bones in the fetal and infant population. For this study, the temporal bone defects and zygomatic bone lesions were macroscopically observed and a descriptive analysis was created. The information garnered from the literature survey was then compared to the individuals from the Kellis 2 cemetery that had the temporal bone defects and zygomatic bone lesions to create a differential diagnosis. A differential diagnosis of the temporal bone defects includes mastoid emissary vein defects and petrosquamous sinus anomalies. A differential diagnosis of the zygomatic bone lesions includes scurvy. Contributing factors may also have been present in order for these defects and lesions to occur. Creating a differential diagnosis of the defects and lesions can provide information on the health, growth, and morbidity of the youngest members of the society related to the Kellis 2 cemetery.
ID: 030646216; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.A.)--University of Central Florida, 2011.; Includes bibliographical references (p. 87-94).
M.A.
Masters
Anthropology
Sciences
Anthropology; Archaeological Investigation Track

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ROEGIERS, FABRICE. "Reorganisations corticales et cytoplasmiques du zygote d'ascidie." Nice, 1999. http://www.theses.fr/1999NICE5286.

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Depuis plus d'un siecle, le developpement determine des ascidies lie a la presence de domaines cytoplasmiques visibles dans leurs ufs et embryons ont attire l'attention des embryologistes. L'un de ces domaines, le myoplasme, une zone sous corticale riche en mitochondries confere aux blastomeres qui en herite la capacite de se developper en cellules musculaires. Nous avons analyse les evenements et phases successives de formation et de reorganisation des domaines cytoplasmiques et corticaux entre la fecondation et la premiere division dans l'ascidie phallusia mammillata. Le spermatozoide fecondant et la vague calcique qu'il declenche initient et orientent une vague de contraction du cortex formant un pole de contraction dont la position dans l'hemisphere vegetatif definit le futur site de gastrulation. Quatre domaines cytoplasmiques et corticaux dont le myoplasme sont ainsi stratifies et concentres autour de ce pole. Un domaine supplementaire apparait ensuite, le corps vegetatif, qui pourrait represente un plasme germinatif. Apres la meiose, deux domaines (le myoplasme sous cortical et un domaine de reticulum endoplasmique cortical) sont relocalises vers l'aster spermatique dont la position definit le pole posterieur de l'embryon. Nous avons mis en evidence une derniere phase de relaxation vegetative au moment de la mitose et des phenomenes de couplage, decouplage puis de recouplage entre la surface et les domaines sous corticaux qui sont medies par le cytosquelette. Nous avons compare la carte des localisations des domaines cytoplasmiques et corticaux et celle de la position des determinants de differenciation et de morphogenese etablies chez differentes especes sur la base d'experiences d'ablations, et de transplantations. Cette comparaison suggere que les determinants des clivages inegaux, de gastrulation et de differenciation de l'endoderme et du muscle sont localises dans les quatre domaines cytoplasmiques et corticaux identifies apres la fecondation.

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Jelínková, Pavla. "Histonový kód a jeho regulace během časného embryonálního vývoje prasete." Master's thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-259245.

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Both pronuclei of the zygote undergo epigenetic changes after fertilization, which determines the quality of the zygote and successful early mammalian embryonic development. Shortly after fertilization epigenetic asymmetry among the pronuclei of the zygote is evident, while the paternal pronucleus undergoes active DNA demethylation, the DNA of the maternal pronucleus remains methylated. The male pronucleus in addition undergoes histone acetylation, whereas the histones of the female pronucleus remain methylated. Asymmetry of pronuclei and their epigenetic status predicts successful reprogramming of the genome, and thus the success of embryonic development. For the successful development of the embryo is therefore required correct formation of both of these pronuclei of the zygote and this formation of pronuclei is regulated by post-translational histone modifications called histone code. It was hypothesized that the histone code is regulated by the activity of NADP+ - dependent histone deacetylases, sirtuins. In the experiment were used fully grown in vitro maturated pig oocytes that were fertilized with pig spermatozoa in vitro. After isolation of zygotes cultured with addition of the activator sirtuin resveratrol was performed immunofluorescence analysis of acetylated and methylated histone H3 at lysine K9 of pronuclei of the zygotes. From the results of control group asymmetry between the pronuclei of the zygote is evident; wherein the male pronucleus exhibits higher acetylation intensity contrast female pronucleus exhibits higher methylation intensity. After adding resveratrol to all experimental groups female pronucleus showed a significant increase of the methylated histone H3 at lysine K9, and contrary to the male pronucleus significant decrease of acetylated histone H3 at lysine K9. Sirtuins are involved in the regulation of histone code in porcine zygote and it can be assumed that they also play a role during subsequent embryonic development, which is the subject of further study.

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Maryníková, Veronika. "Úloha sirtuinů během formace prvojader po in vitro oplození prasečích oocytů." Master's thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-259246.

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Recently, the increasing importance of reproductive biotechnologies rises. They provide us to get higher performance of livestock or to improve treatment in human medicine. It is neccessary to have a sufficient amount of developmentaly competent oocytes and further healthy liveable embryos for in vitro culture to supply a progress of reproductive technologies. Immediately after fertilization, pronucleus formation is a key moment for further embryonicdevelopment. Male and female pronuclei have their own pattern of histone code. For development of early embryo, it is neccessary to supply the correct pattern of histone code. NAD+-dependent histon deacetylases, sirtuins, are one of the mechanism which plays in regulation of histone code. These family contains seven isoforms, SIRT1-7. Based on current research, we decided for hypothesis that sirtuins are present in porcine fertilized oocytes and regulate the pronucleus formation. In this thesis, porcine COCs were culture in modificated culture medium and after 44 hr. maturation, only oocytes with extruded first polar body were chosen and used for further in vitro fertilization. Presumed zygotes were subsequently cultured with sirtuins inhibitors, nicotinamide or sirtinol. After 22 hr. of in vitro culture, zygotes were subjected by imunocytochemicaly localization of methylated and acetylated (on lysine K9) histone H3 and image analysis. Our results show that SIRT1 is localizated in porcine zygotes, especially in pronuclei. There are changes in acetylation and methylation H3K9 after sirtuin inhibition. Significant increase of H3K9 acetylation and decrese in H3K9 methylation are appeared. Sirtinol usage has confirmed that the changes are result of SIRT1 action. Role of SIRT1 in histone code regulation of pronucleus formation is still not enought described in porcine.

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Phillips, Jennifer Barber. "Spatio-temporal regulation of microtubule stability in the Caenorhabditis elegans zygote /." view abstract or download file of text, 2003. http://wwwlib.umi.com/cr/uoregon/fullcit?p3113023.

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Thesis (Ph. D.)--University of Oregon, 2003.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 75-80). Also available for download via the World Wide Web; free to University of Oregon users.

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Caspar, Philippe. "La Saisie du zygote humain par l'esprit : destin de l'ontogenèse aristotélicienne /." Paris : Namur : Lethielleux ; Culture et vérité, 1987. http://catalogue.bnf.fr/ark:/12148/cb349700587.

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Arney, Katharine Luisa. "Epigenetic modification in the mouse zygote and regulation of imprinted genes." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620401.

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Corellou, Florence. "Cycle cellulaire et polarisation du zygote de fucus regulations et interactions." Rennes 1, 2000. http://hal.upmc.fr/tel-01115123.

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L'orchestration correcte de la differenciation et du cycle cellulaire est necessaire au developpement de tout organisme. Chez les vegetaux, il n'existe que peu de donnees sur les mecanismes moleculaires mis en jeu pour coordonner ces deux evenements. Le zygote de l'algue brune fucus est un modele de l'embryogenese precoce des vegetaux. La polarisation du zygote de fucus s'effectue apres la fecondation et coincide avec le premier cycle cellulaire mitotique. Des acteurs moleculaires impliques dans la polarisation zygotique ont ete identifies mais les voies de transduction controlant l'etablissement de la polarite restent a preciser. Par ailleurs les connaissances sur le cycle cellulaire du fucus sont tres reduites. Dans ce contexte, nous avons voulu savoir comment la polarisation et le cycle cellulaire sont regules et s'il existe des interactions entre ces deux evenements. Nous avons montre que le cycle cellulaire presente quatre phases g 1, s, g 2 et m bien definies, possede les mecanismes de surveillance usuels, qui rendent la mitose dependante de la replication et de l'assemblage correct du fuseau, et que sa progression (transitions g 1/s, g 2/m, sortie de mitose, cytodierese) depend etroitement de l'activite de proteines de type kinases dependantes des cylines (cdk). Deux cdk a motif pstaire, p32 et p34, sont traduites a partir arnm maternels, apres la fecondation, et leur synthese progressive correspond a l'augmentation de l'activite kinase des cdk, dont le pic mitotique requiert la transcription d'un regulateur positif. Ces deux cdk sont negativement regulees par phosphorylation sur tyrosine, lors de la progression normale et lors de l'activation du point de controle de la replication de l'adn. P34 est specifiquement liee par l'inhibiteur de cdk, purvalanol, et jouerait un role majeur dans le controle du cycle cellulaire. Nous avons montre que, a la transition g 1/s, la cdk p34 controle egalement la formation de l'axe de polarite embryonnaire, qui s'effectue durant la phase s. D'autre part nous avons mis en evidence que la formation de l'axe est essentielle au modelage de l'embryon et qu'elle est regulee par des proteines de type tyrosine-kinases. Ces kinases ne sont pas necessaires a la division. Aussi, si la formation de l'axe de polarite est sous le controle du cycle cellulaire, la reciproque reste a demontrer.

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Tzima, Sofia. "ZYGOS : une revue d'art en Grèce (1955-1966)." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAG030.

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Cette thèse se propose d’étudier le discours de la revue grecque d’art Zygos (« Balance ») et son rôle dans la réception et la promotion de mouvements artistiques et dans la diffusion de courants idéologiques en Grèce. L’étude des textes de Zygos révèle l’opposition « grécité – modernisme » comme thème central du discours de la revue. Notre conclusion principale est que Zygos a manifesté un engagement mesuré dans la modernité, en réconciliant le modernisme avec le désir de particularité grecque. Nous constatons la présence d’un discours sur l’art moderne conçu comme une évolution de Cézanne à l’art abstrait, à travers le cubisme. Cependant, cette revue est aussi le lieu d’un discours dont les points saillants sont la mesure, l’humanisme et les affinités entre l’« esprit français » et l’« esprit grec ». Plusieurs auteurs de Zygos défendent la nécessité d’un chemin intermédiaire pour l’art entre imitation fidèle et rupture complète avec la nature
The object of this thesis is to study the discourse of the Greek art journal Zygos (“Balance”) and its role in the reception and promotion of art mouvements and ideological currents in Greece. The study of Zygos texts reveals the opposition “greekness – modernism” as the main theme of this journal’s discourse. Our main conclusion is that Zygos showed a moderate promotion of modernity, reconciliating modernism with a desire of a Greek particularity. We note the presence of a discourse on modern art conceived as an evolution from Cézanne to abstract art, through cubism. However, this review also expresses a discourse whose main points are measure, humanism and the affinities between the “French spirit” and the “Greek spirit”. Several authors of Zygos defend the necessity of an intermediate way for art between faithful imitation of nature and complete rupture with it

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Delabaere, Laetitia. "Réplication, condensation et division des chromosomes parentaux dans le zygote de drosophile." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10280/document.

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Chez les animaux, la conformation unique du noyau du spermatozoïde dont la chromatine est organisée avec des protéines chromosomiques spécifiques telles que les protamines le rend totalement inactif. Le remodelage de la chromatine paternelle à la fécondation par des activités d'origine maternelle sont donc des processus essentiels à la formation d'un embryon diploïde, dont les mécanismes restent très mal connus. Lors de ma thèse j'ai essayé de mieux comprendre ces processus par l'étude, chez la drosophile, d'un mutant létal embryonnaire à effet maternel : maternal haploid (mh). Ce mutant affecte l'incorporation des chromosomes paternels à la première division zygotique menant à la formation d'embryons haploïdes gynogénétiques. L'identification du gène de mh comme CG9203 m'ont permis de caractériser sa fonction. Dans les œufs mh, les chromosomes paternels se condensent anormalement et ne parviennent pas à se diviser correctement lors de la première mitose de l'embryon. Récemment, des études sur son orthologue humain, appelé Spartan/DVC1, ont montré qu'il était impliqué dans la synthèse translésionnelle (TLS), un mécanisme de tolérance aux dommages d'ADN. J'ai pu démontrer que dans les cellules somatiques, la fonction de Spartan dans le TLS est conservée chez la drosophile. Cependant, la fonction maternelle de MH ne relève pas du TLS canonique, mais permet de maintenir l'intégrité de l'ADN paternel avant la réplication. Ensemble, mes travaux soulignent la singularité du pronoyau mâle et la complexité que présente le maintien de son intégrité à la fécondation
In animals, sexual reproduction requires the union between two distinct parental gametes: the spermatozoon and the oocyte. The unique nuclear conformation of the sperm, in which the chromatin is organized with sperm-specific chromosomal protein like protamines, abolishes its activity. The paternal chromatin remodeling and the maintenance of its integrity at fertilization by maternal activities are therefore essential processes for zygote formation. However, although their mechanisms are crucial, they remain poorly understood. During my thesis, I tried to better understand the processes involved during de novo paternal chromatin assembly in Drosophila through the study of a maternal embryonic lethal mutation: maternal haploid (mh). The mutant affects the incorporation of paternal chromosomes during the first zygotic division, leading to the development of gynogenetic haploid embryos. The identification of the mh gene as CG9203, and the generation of the null allele mh2 allowed me to characterize its function. In eggs led by mh mutant females, paternal chromosomes abnormally condense and fail to divide leading to the formation of chromatin bridges at the first embryonic division. Recently, its human ortholog Spartan/DVC1, has been described to be involved in translesion synthesis (TLS), a DNA damage tolerance pathway that ensures replication fork progression. Combining genetic and cytological approaches, I demonstrated that the Spartan function in TLS is conserved in Drosophila. However, I discovered that the critical function of MH during the first embryonic division, was not consistent with a canonical TLS. Alternatively, it is specifically required to maintain paternal integrity and to allow its proper replication at the first cycle. The mh phenotype characterization, led me to compare it with others phenotypes induced by the knock-down of replication factors and to study parental chromosome condensation in the zygote. Surprisingly, one of the proteins allowing the establishment of the pre-replication complex is dispensable for the proper paternal chromosome segregation contrarily to the maternal counterpart. Altogether, these works highlight the difference that exists between the two parental pronuclei and the complexity of maintaining their integrity at fertilization

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Algazeery, Ahmed. "La Yemanucléine de Drosophile est nécessaire à la méiose ovocytaire et l’assemblage de la chromatine paternelle dans le zygote." Thesis, Montpellier 1, 2013. http://www.theses.fr/2013MON1T034/document.

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La reproduction sexuée repose sur deux processus fondamentaux : la méiose qui permet la formation des gamètes dont le génome est haploïde et la syngamie qui permet, après fécondation, de restaurer la diploïdie par fusion des deux noyaux parentaux haploïdes. Alors que la méiose repose respectivement sur le génome maternel pour l'ovocyte et paternel pour le spermatozoïde, la restauration de la diploïdie dans le zygote repose exclusivement sur le génome maternel. Si un pronucleus maternel compétent pour la réplication est formé au terme de la méiose ovocytaire, le génome paternel quant à lui, n'acquiert cette compétence que sous l'influence de facteurs maternels. En effet, à la fin de la méiose, le génome paternel est « empaqueté » avec des protamines qui le rendent inactif pour toute fonction biologique, en particulier la réplication. L'éviction des protamines et leur remplacement par des histones maternelles sont des étapes indispensables à l'acquisition par le génome paternel de sa compétence à la réplication, préalable à la syngamie. Tous ces événements doivent être extrêmement coordonnés afin de permettre à un premier noyau zygotique comportant les deux lots de chromosomes parentaux de se former et d'entrer dans le premier cycle mitotique.Notre laboratoire a identifié yemanuclein-alpha, aussi appelé yemanuclein (yem) dans un crible moléculaire pour des gènes exprimés spécifiquement dans la lignée germinale femelle, et son premier allèle muté yem1. Cette mutation ponctuelle (V478E) a été identifiée dans un crible génétique de « stérilité femelle ». Une descendance exceptionnelle observée chez les femelles yem1, présente la propriété inattendue d'être parthénogénétique. Cette propriété révèle un double défaut chez le mutant : dans le processus de méiose ovocytaire qui conduit à la formation d'un pronucleus maternel haploïde mais aussi dans la formation d'un pronucleus paternel compétent pour la syngamie. Mes travaux de thèse ont porté sur les deux aspects de la fonction de la Yemanucléine. En conjuguant des méthodes de génétique, de biochimie, et de biologie cellulaire, nous avons pu mettre en évidence des fonctions essentielles de la Yemanucléine dans les étapes initiales de la prophase méiotique de l'ovocyte de drosophile. Nous avons pu montrer que la Yemanucléine joue un rôle clé dans la recombinaison méiotique et plus particulièrement dans la fréquence et la cinétique d'apparition des cassures double brin. Son association au complexe synaptonémal et au complexe cohésine, tous deux connus comme étant nécessaires à la ségrégation chromosomique, est un élément clé de cette fonction.Outre cette fonction méiotique, la Yemanucléine, facteur maternel, est aussi requise pour l'assemblage de la chromatine du pronucleus paternel. Nous montrons dans ce manuscrit qu'elle joue ce rôle à travers son action dans un troisième complexe, en partenariat avec la protéine HIRA. Le complexe multiprotéique contenant la protéine HIRA est connu pour sa fonction de chaperon du variant de l'histone H3.3 et son rôle dans l'assemblage de la chromatine du pronucleus paternel. La Yemanucléine est le premier membre de la famille HPC2/UBN1 caractérisé. Son rôle dans l'assemblage des nucléosomes découplé de la réplication est décrit pour la première fois dans ce manuscrit. C'est aussi la première fois qu'une protéine spécifique de la reproduction est décrite pour son implication à deux étapes clés de ce processus
Sexual reproduction relies on two key events: formation of cells with a haploid genome through meiosis and restoration of diploidy through syngamy in the zygote. Meiosis completion is supported exclusively by the maternal genome for the oocyte and the paternal genome for the sperm cell. In contrast diploidy restoration in the zygote is entirely dependent on maternal factors. At the end of meiosis the maternal pronucleus is competent for replication, whereas the paternal genome is packed with protamines. These proteins need to be removed in the zygote and replaced by maternally provided histones before the paternal genome acquires competence for replication, a prerequisite for syngamy. All these events must be highly coordinated to allow the first zygotic nucleus to form with the two sets of parental chromosomes and enter the first mitotic cycle. Our laboratory has identified yemanuclein-alpha, also called yemanuclein (yem) in a molecular screen for genes specifically expressed in the female germ line and its first mutant allele yem1, in a female sterile screen. The role played by yem not only in the meiotic process through which a haploid maternal pronucleus is formed but also in the zygotic process that makes a paternal pronucleus competent for syngamy, is underscored by the obtention of exceptional parthenogenetic progeny from yem1 mothers.My thesis work is precisely dedicated to the analysis of both aspects of Yemanuclein function: in the oocyte and the zygote. Using genetic, biochemical and cell biology methods we were able to uncover essential functions of Yemanuclein in early meiotic prophase in the Drosophila oocyte. Using yem1 allele (V478E), we could show its requirement for meiotic recombination especially for the frequency and timing of the double strand breaks formation. Yemanuclein association with two protein complexes, the Synaptonemal Complex (SC) and the Cohesin complex known to be required for proper chromosome segregation, supports these findings. Beyond its meiotic function, Yemanuclein is also required in the zygote for assembly of paternal pronucleus chromatin. This is achieved through a third complex that acts as histone H3.3 chaperone. In the present manuscript we identify Yemanuclein as a partner of HIRA in its role in H3.3 nucleosome assembly and deposition on the paternal pronucleus. Interestingly Yemanuclein is the first member of the HPC2/UBN1 protein family ever characterized. The role of Yem/ HPC2/ UBN1 in replication independent chromatin remodeling remained elusive until very recently. Our work is original in that it is the first to report on a role of one member of this family in oocyte meiosis and paternal chromatin assembly in the zygote

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Small, Lawrence Edward. "PAR Proteins Regulate CDC-42-Dependent Myosin Dynamics During C. elegans Zygote Polarization." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461086954.

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17

Ni, Chun-Lun. "Polyglutamine Tract Expansion Increases Protein S-Nitrosylation and the Budding Yeast Zygote Transcriptome." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1481200808487517.

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18

Patil, Harshal [Verfasser], and Michael [Akademischer Betreuer] Lanzer. "Studies on Zygote Morphogenesis in rodent Malaria parasite, Plasmodium berghei / Harshal Patil ; Betreuer: Michael Lanzer." Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180502620/34.

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19

Berger, Frédéric. "Quelques aspects de la biologie cellulaire du développement précoce (polarisation, embryogenèse) du zygote de Fucus." Lyon 1, 1994. http://www.theses.fr/1994LYO1T310.

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20

Anim-Kwapong, Gilbert John. "The potential roles of Albizia zygia in cocoa plantation systems of Ghana." Thesis, Bangor University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239969.

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21

Timlin, Claire. "Strategies for Improving Reproductive Efficiency of Beef Cattle with Assisted Reproductive Technologies." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/98841.

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Reproductive efficiency in beef cattle can be improved with reproductive technologies at the herd, individual cow, and embryonic levels. Decreasing the bull:cow ratio for natural service after fixed time artificial insemination (FTAI) can alleviate economic burden associated with FTAI. In experiment 1, the total number of cows exposed per bull was negatively correlated with pregnancy rate to natural service on first return to estrus after FTAI in fall herds. The number of open cows per bull in fall herds using one natural service sire was negatively correlated with pregnancy rate on first return to estrus. There was no correlation between number of cows exposed per bull and pregnancy rates in fall herds with multiple sires or in spring herds. However, bull:cow ratio accounted for only 5–11% of the variation in pregnancy rates, thus we conclude that a reduced bull:cow ratio did not affect natural service return to estrus pregnancy rate. Experiment 2 examined how supplementing calcium salts of soybean oil (CSSO) improves beef cow fertility. Non-pregnant cows received supplement with either saturated fat or omega-6 rich CSSO. There were no changes in dominant follicle diameter, corpus luteum volume, plasma progesterone, or endometrial gene expression (PTGES and AK1B1, PPARA, PPARA, PPARD) between treatments. Plasma and follicular fluid fatty acid compositions were altered between treatments. Experiment 3 examined if size parameters of zygotes have potential as a non-invasive, objective embryo selection method. The outer diameter, area of ooplasm, and thickness of zona pellucida (ZP) was digitally measured on individual artificially activated oocytes and in-vitro fertilized (IVF) zygotes. Larger outer diameter increased probability of development to the blastocyst stage by days 7 and 8 for activated oocytes and tended to by day 8 for IVF zygotes. Thinner ZP increased probability of development to blastocyst stage on days 7 and 8 for oocytes, and to day 8 for IVF zygotes. Area did not affect development but was positively correlated with blastomere number on day 8. An interaction between diameter and ZP thickness was observed in zygotes, but not activated oocytes, suggesting oocyte activation is not always a suitable replacement for in-vitro fertilization.
Doctor of Philosophy
We need to improve reproductive efficiency in beef cows if we are to combat the challenges of producing more food while using less resources due to limited land availability and concerns with greenhouse gas emissions from agriculture. In cow-calf production systems, this means producing one healthy calf per cow per year. Cattlemen can implement a variety of assisted reproductive technologies to achieve this goal. Achieving maximal reproductive efficiency will require using technologies that are incorporated into herd management, individual animal care, and in vitro embryo production. Fixed time artificial insemination (FTAI) allows cattlemen to maximize the number of cows becoming pregnant and calving earlier in the season to increase efficiency. Unfortunately, use of FTAI is uncommon in cow-calf production systems because of labor and economic restraints. In order to improve economic feasibility of FTAI, bull-related costs need to be reduced, which can be done through increasing the number of cows serviced per bull (decreasing the bull:cow ratio). This study retrospectively examined correlations between the bull:cow ratio and pregnancy rate on first return to estrus after FTAI. There was little to no correlations between bull:cow ratio and pregnancy rates, and if they were significant, there was much variation in the data. With this we concluded that a reduced bull:cow ratio does not affect pregnancy rate on first return to estrus, allowing producers to increase the number of cows serviced by a single bull and reduce bull related costs. Supplementing calcium salts of soybean oil (CSSO) that are rich in omega-6 fatty acids can enhance beef cow fertility, but it is unclear why this happens. Using non-pregnant cows as a model, we studied the effects of either saturated fat or CSSO on reproductive parameters such as ovarian structures, hormone concentrations, and uterine gene expression. There were no changes in any of these parameters between treatments, but there were changes in the concentrations of certain plasma and follicular fluid fatty acids. There was also reduced activity of lipid metabolism enzymes. We were unable to pinpoint how CSSO supplementation improves reproduction, but the altered fatty acid content of tissues and altered enzyme activity likely plays a key role, thus ultimately impacting fatty acid utilization and growth of the embryo. In-vitro embryo production can increase the number of offspring produced from a single female and accelerate the incorporation of animals with high genetic merit into herds. To obtain optimal pregnancy rates with in vitro embryos, we should develop non-invasive, objective methods for identifying the most viable embryos. This study examined if size parameters of activated and fertilized oocytes are indicative of successful development. We discovered that oocytes with large diameters and those with thin zona pellucida were most likely to develop to the blastocyst stage, and that the area of the cell was positively correlated with blastocyst total cell number. An interaction between diameter and ZP thickness was observed in zygotes, but not activated oocytes, suggesting oocyte activation is not always a suitable replacement for in-vitro fertilization. This suggests that digital measurements of fertilized oocytes may have potential as objective selection criteria. Addressing issues of reproductive inefficiency in beef cows requires a comprehensive approach, as there is not one ideal solution. Management techniques can alleviate the cost of FTAI by reducing the number of bulls used without affecting pregnancy rates. Supplementing CSSO can alter tissue fatty acids to enhance fertility. Finally, the efficiency of in vitro embryo production can be improved by selecting better embryos for transfer without compromising the embryo. Combinations of all these techniques can create more reproductively efficient animals.

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Timlin, Claire Lourdine. "Strategies for Improving Reproductive Efficiency of Beef Cattle with Assisted Reproductive Technologies." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/98841.

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Reproductive efficiency in beef cattle can be improved with reproductive technologies at the herd, individual cow, and embryonic levels. Decreasing the bull:cow ratio for natural service after fixed time artificial insemination (FTAI) can alleviate economic burden associated with FTAI. In experiment 1, the total number of cows exposed per bull was negatively correlated with pregnancy rate to natural service on first return to estrus after FTAI in fall herds. The number of open cows per bull in fall herds using one natural service sire was negatively correlated with pregnancy rate on first return to estrus. There was no correlation between number of cows exposed per bull and pregnancy rates in fall herds with multiple sires or in spring herds. However, bull:cow ratio accounted for only 5–11% of the variation in pregnancy rates, thus we conclude that a reduced bull:cow ratio did not affect natural service return to estrus pregnancy rate. Experiment 2 examined how supplementing calcium salts of soybean oil (CSSO) improves beef cow fertility. Non-pregnant cows received supplement with either saturated fat or omega-6 rich CSSO. There were no changes in dominant follicle diameter, corpus luteum volume, plasma progesterone, or endometrial gene expression (PTGES and AK1B1, PPARA, PPARA, PPARD) between treatments. Plasma and follicular fluid fatty acid compositions were altered between treatments. Experiment 3 examined if size parameters of zygotes have potential as a non-invasive, objective embryo selection method. The outer diameter, area of ooplasm, and thickness of zona pellucida (ZP) was digitally measured on individual artificially activated oocytes and in-vitro fertilized (IVF) zygotes. Larger outer diameter increased probability of development to the blastocyst stage by days 7 and 8 for activated oocytes and tended to by day 8 for IVF zygotes. Thinner ZP increased probability of development to blastocyst stage on days 7 and 8 for oocytes, and to day 8 for IVF zygotes. Area did not affect development but was positively correlated with blastomere number on day 8. An interaction between diameter and ZP thickness was observed in zygotes, but not activated oocytes, suggesting oocyte activation is not always a suitable replacement for in-vitro fertilization.
Doctor of Philosophy
We need to improve reproductive efficiency in beef cows if we are to combat the challenges of producing more food while using less resources due to limited land availability and concerns with greenhouse gas emissions from agriculture. In cow-calf production systems, this means producing one healthy calf per cow per year. Cattlemen can implement a variety of assisted reproductive technologies to achieve this goal. Achieving maximal reproductive efficiency will require using technologies that are incorporated into herd management, individual animal care, and in vitro embryo production. Fixed time artificial insemination (FTAI) allows cattlemen to maximize the number of cows becoming pregnant and calving earlier in the season to increase efficiency. Unfortunately, use of FTAI is uncommon in cow-calf production systems because of labor and economic restraints. In order to improve economic feasibility of FTAI, bull-related costs need to be reduced, which can be done through increasing the number of cows serviced per bull (decreasing the bull:cow ratio). This study retrospectively examined correlations between the bull:cow ratio and pregnancy rate on first return to estrus after FTAI. There was little to no correlations between bull:cow ratio and pregnancy rates, and if they were significant, there was much variation in the data. With this we concluded that a reduced bull:cow ratio does not affect pregnancy rate on first return to estrus, allowing producers to increase the number of cows serviced by a single bull and reduce bull related costs. Supplementing calcium salts of soybean oil (CSSO) that are rich in omega-6 fatty acids can enhance beef cow fertility, but it is unclear why this happens. Using non-pregnant cows as a model, we studied the effects of either saturated fat or CSSO on reproductive parameters such as ovarian structures, hormone concentrations, and uterine gene expression. There were no changes in any of these parameters between treatments, but there were changes in the concentrations of certain plasma and follicular fluid fatty acids. There was also reduced activity of lipid metabolism enzymes. We were unable to pinpoint how CSSO supplementation improves reproduction, but the altered fatty acid content of tissues and altered enzyme activity likely plays a key role, thus ultimately impacting fatty acid utilization and growth of the embryo. In-vitro embryo production can increase the number of offspring produced from a single female and accelerate the incorporation of animals with high genetic merit into herds. To obtain optimal pregnancy rates with in vitro embryos, we should develop non-invasive, objective methods for identifying the most viable embryos. This study examined if size parameters of activated and fertilized oocytes are indicative of successful development. We discovered that oocytes with large diameters and those with thin zona pellucida were most likely to develop to the blastocyst stage, and that the area of the cell was positively correlated with blastocyst total cell number. An interaction between diameter and ZP thickness was observed in zygotes, but not activated oocytes, suggesting oocyte activation is not always a suitable replacement for in-vitro fertilization. This suggests that digital measurements of fertilized oocytes may have potential as objective selection criteria Addressing issues of reproductive inefficiency in beef cows requires a comprehensive approach, as there is not one ideal solution. Management techniques can alleviate the cost of FTAI by reducing the number of bulls used without affecting pregnancy rates. Supplementing CSSO can alter tissue fatty acids to enhance fertility. Finally, the efficiency of in vitro embryo production can be improved by selecting better embryos for transfer without compromising the embryo. Combinations of all these techniques can create more reproductively efficient animals.

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Seguin, Diane G. "Short-term recovery from a volume increase in the mouse zygote, characteristics of regulatory volume decrease in vitro." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0015/MQ48180.pdf.

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24

Séguin, Diane G. "Short-term recovery from a volume increase in the mouse zygote: Characteristics of regulatory volume decrease in vitro." Thesis, University of Ottawa (Canada), 2000. http://hdl.handle.net/10393/9230.

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Mouse zygotes have been shown to recover from an imposed increase in volume, a process known as a regulatory volume decrease or RVD, via separate but functionally coupled Cl- and K+ channels. The objectives of this thesis were to further determine some of the characteristics of these Cl- and K+ channels involved in RVD in the mouse zygote. It was proposed that the Cl - channel in mouse zygotes was a swelling-activated Cl -/organic osmolyte channel like that found in many other cells. A method developed by Passantes-Morales et al. (1993) was used, in which a large extracellular concentration of one of a number of organic osmolytes was added to the experimental media, and the ability of the zygote to perform RVD in the presence of each was determined. A number of organic compounds demonstrated an inhibition of RVD, and thus, identified a number of organic compounds which might function as organic osmolytes in embryos. To directly test whether swelling of zygotes increased their permeability to organic osmolytes; the permeability in swelled zygotes was compared to that in non-swelled zygotes, using 3H glycine. (Abstract shortened by UMI.)

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Mateo, Cuadros Sílvi. "Zigots monopronucleats: origen, desenvolupament i constitució cromosòmica." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/461590.

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L’observació de zigots amb un únic pronucli (PN) idos corpuscles polars (CP) en el moment de la valoració de la fecundació es dóna entre el 3%-6% deis oocits inseminats mitjanant injecció intracitoplasmatica d’un espermatozoide (ICSI). La incertesa sobre el destí que se’ls ha de donar fa necessari un estudi del potencial reproductiu que poden tenir els embrions que se’n deriven. Així mateix, cal coneixer els riscos que poden derivar de la seva utilització. Per aquestes raons,eltreball realitzat durant aquesta tesi doctoral ha estat centrat en l’estudi de la constitució cromosomica i el desenvolupament in vitro deis zigots monopronucleats (lPN) amb 2CP provinents d’ICSI. Els resultats obtinguts mostren que els embrions que provenen de zigots PN 2CP d’ICSI deriven majoritiiriament d’un procés de fecundació amb participació del material genetic de l’espermatozoi de. El major diametre de pronucli, observat en la majoria de zigots PN d’ICSI respecte als 2PN, es podria explicar per la formació d’un únic embolcall nuclear que englobés el material genetic, matern ipatern,en una sola estructura pronuclear, idonaria suport a la hipotesi de l’origen genetic biparental. No obstant, no es pot descartar que alguns embrions derivats de zigots monopronucleats d’ICSI presentin un genoma d’origen uniparental. Els zigots PN 2CP d’ICSI mostren una menor capacitat de desenvolupament in vitro respecte els 2PN 2CP d’ICSI,observant-se un alt percentatge d’embrions que aturen el seu desenvolupament en estadis primerencs. Les taxes de zigots monopronucleats que assoleixen l’estadi de blastocist varien entre el 3,4%- 28,9% essent inferiors a les observades en embrions derivats de zigots 2PN 2CP d’ICSI. L’estudi de la morfocinetica deis zigots monopronucleats d’ICSI ha mostrat diferencies en la cinetica de formació idesaparició del pronucli ien el retard de les primeres divisions embrionaries amb la deis embrions derivats de zigots 2PN. Malgrat tot, aquells zigots PN que formen blastocist tenen una cinetica similar a la deis blastocists provinents de zigots 2PN, excepte en el temps de compactació,que es veu retardat iperllongat. L’estudi de la constitució cromosomica deis embrions derivats de zigots PN 2CP d’ICSI ha demostrat que un alt percentatge d’aquests embrions són cromosomicament anormals, amb un elevat grau de mosaTcisme. Els percentatges d’aneuplo”idia més elevats han estat observats en aquells embrions que bloquegen el desenvolupament in vitro en estadis primerencs, mentre que aquells que assoleixen l’estadi de blastocist presenten un major percentatge d’euplo”idia. Els resultats obtinguts indiquen que els embrions derivats de zigots monopronucleats d’ICSI no han de ser mai la primera opció per a la transferencia. La publicació del naixement d’una nena sana provinent d’un zigot monopronucleat analitzat geneticament obre una alternativa quan no es disposa d’altres embrions viables provinents de zigots 2PN 2CP. En aquests casos,l’anl:tlisi genetic seria obligat. Per tal de millorar els resultats imaximitzar el cost-benefici de l’analisi, l’estudi genetic deis embrions derivats de zigots PN d’ICSI hauria de realitzar-se en estadi de blastocists mitjançant tecniques que permetin l’analisi de la dotació cromosomica i l’origen biparental. La transferencia d’aquests embrions només podria ser considerada després d’una informació exhaustiva deis riscos iun assessorament reproductiu acurat.
The observation of zygotes with a single pronucleus (PN) and two polar bodies (PB) at the moment of the fertilization check is about 3%-6% of the oocytes inseminated by intracytoplasmic sperm injection (ICSI). The uncertainty about their use made it necessary to perform a study about the reproductive potential that the embryos derived from the monopronucleated (lPN}ICSI zygotes may have. Furthermore,there was a clear need to identify the risks associated with their use. Forthese reasons,the work performed during this doctoral thesis was focused on the study of the chromosomal constitution and the in vitro development of the monopronucleated zygotes with 2PB after ICSI. The results obtained through the study show that embryos derived from the lPN 2PB ICSI zygotes come mainly from a fertilization process with the participation of the sperm genetic material. The higher pronucleus diameter observed in the majority of the lPN ICSI zygotes compared with the 2PN ones, could be explained by the formation of a single membrane that included the maternal and paternal genomes in a single pronucleus, which supports the hypothesis of a biparental origin. Even though,it is not possible to rule out that sorne embryos derived from the monopronucleated ICSI zygotes showed a uniparental genome. The monopronucleated ICSI zygotes showed an impaired in vitro development with respect to the 2PN 2PB ICSI zygotes, displaying a high percentage of embryos that arrested their development at early stages. The monopronucleated zygotes that reached the blastocysts stage varied between 3.4% and 28.9%,the percentage being lower than of those comingfrom the 2PN 2PB ICSI zygotes. The morphokinetic study of the monopronucleated ICSI zygotes showed differences in the pronuclear appearance and the fading kinetics as well as slowed cleavage in the first embryonic stages compared with the 2PN zygotes. However, with the exception of compaction time,wich appeared to be delayed and elongated, those PN zygotes that achieved the blastocyst stage had similar kinetic behaviour to the blastocysts comingfrom the 2PN zygotes. The study of chromosomal constitution of embryos coming from lPN 2PB ICSI zygotes showed that a high percentage of these embryos were chromosomally abnormal, displaying a high rate of mosaicism. The higher rate of aneuploidy was observed in the embryos that arrested their development at early stages, while those embryos that achieved the blastocyst stage showed a higher euploidy rate. The results obtained show that the embryos derived from the monopronucleated ICSI zygotes should never be the first choice for embryo transfer. The publication of the birth of a healthy baby coming from a monopronucleated ICSI zygote after a genetic analysis opens an alternative when no other embryos comingfrom the 2PN 2PB zygotes are available. Inthese cases,the genetic analysis has to be mandatory. In arder to improve the results and maximise the cost-benefit of the analysis,the genetic study of embryos derived from the lPN ICSI zygotes should be performed at the blastocyst stage by techniques that allow a comprehensive chromosomal screening and the confirmation of the biparental origin. The transfer of these embryos should only be considered after exhaustive information on the associated risks and accurate reproductive counsel.

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Siméon, Amandine. "Localisations et rôles des polysaccharides de paroi au cours du développement de deux modèles d’algues brunes : le zygote de Fucus et Ectocarpu." Electronic Thesis or Diss., Sorbonne université, 2018. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2018SORUS233.pdf.

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La paroi des algues brunes constitue un compartiment cellulaire majeur impliqué dans de nombreuses réponses physiologiques dont la croissance cellulaire, le développement, ou encore dans l’adaptation aux variations physico-chimiques de l’environnement. Tout comme d’autres organismes photosynthétiques (plantes, algues rouges et vertes), les algues brunes ont une paroi essentiellement composée de polysaccharides, mais compte-tenu des distances phylogénétiques, les composés sont distincts, avec nottament des alginates et des fucanes sulfatés. La majorité des connaissances sur ces compositions dérive d’extractions chimiques effectuées sur des algues entières, au cours desquelles l’information cellulaire est perdue. Aujourd’hui, des anticorps monoclonaux spécifiques d’alginates et de fucanes d’algues brunes ont été développés et caractérisés. Ces outils peuvent être utilisés pour localiser précisément à un niveau cellulaire et tissulaire des fractions polysaccharidiques particulières. Outre des informations sur la structure et la composition de la paroi, ces anticorps permettent d’étudier les rôles de ces polysaccharides dans de nombreuses réponses physiologiques, dont le développement. Afin d’étudier ces aspects, deux organismes modèles d’algues brunes, le zygote de Fucus et les sporophytes d’Ectocarpus ont été utilisés. Lors de cette thèse, des glycoprotéines minoritaires, des AGPs (arabino-galactanes protéines) ont été mises en évidence dans la paroi des algues brunes avec des fonctions majeures dans l’embryogénèse chez Fucus. L’utilisation de nos anticorps monoclonaux spécifiques a permis de montrer la dynamique de la mise en place des alginates et des fucanes au cours du développement de nos modèles. J’ai ainsi pu montrer l’implication des fucanes dans la croissance apicale et le rôle crucial du sulfate présent dans l’environnement, dans ce processus
The cell wall of brown algae is a major cell compartment involved in many physiological responses including cell growth, development, or in adaptation to the physico-chemical changes of the environment. Like other photosynthetic organisms (plants, red and green algae), brown algae have a cell wall mainly composed of polysaccharides, but taking into account phylogenetic distances, the compounds are distinct, with notably alginates and sulfated fucans. Most knowledge on cell wall compositions comes from chemical extractions carried out on whole algal plants, with the induced lost of most cellular information. Today, monoclonal antibodies specifically dericted against alginates and sulfated fucans have been developed and characterized. These tools can be used to precisely localize at a cellular and tissue level their particular polysaccharide fractions. In addition to the information on the structure and composition of the cell wall, these antibodies allow to study the biological roles of the cell wall in many functional responses, including during early development. In this study, two model organisms of brown algae, the zygote of Fucus and the sporophytes of Ectocarpus, were used. In term of cell wall composition, glycoproteins known as arabinogalactan proteins (AGPs) have been identified as minor components in the cell walls of brown algae. They were shown to have a functional role in the Fucus embryogenesis. The use of our specific monoclonal antibodies allowed to locate alginates and fucans in cell walls during the development of our models. Notably, I have shown the involvement of sulfated fucans in normal apical growth and the crucial role of sulfate in this process

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au, M. Wheeler@murdoch edu, and Margaret Wheeler. "Reproductive and Molecular Biology of Eucalyptus marginata." Murdoch University, 2004. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040723.140250.

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This thesis examined aspects of the reproductive and molecular biology of Eucalyptus marginata (jarrah). The aims were to develop protocols for controlled pollination, that could be used in clonal orchard trees to breed jarrah seedlings that have a known genetic resistance to Phytophthora cinnamomi (dieback), for use in rehabilitation after mining and logging. An intimate knowledge of the breeding biology of jarrah was necessary to achieve this aim. The project also aimed to increase knowledge of the genetic diversity and structure of jarrah, in order to make informed decisions regarding the collection of material to be used for clonal propagation. Previous research has had little success in producing viable seed from any controlled pollinations, but clonal material resistant to P. cinnamomi has been produced using tissue culture. The question posed in this thesis was Can we improve breeding and propagation techniques of jarrah? Techniques were developed for testing of in vitro pollen viability and pollen storage, pollination and fertilisation success after controlled pollinations, including determination of stigma receptivity and development of bud isolation techniques using alfoil. The variation in female fertility between genotypes was examined. The use of paclobutrazol was explored as a method of increasing the level of viable seed production in clonal orchard trees. The use of fertiliser as well as the growth retardant was also explored to see if it increased the level of seed production even more. Genetic diversity, genetic differentiation and phylogeny within Eucalyptus marginata were examined using nuclear and chloroplast DNA analysis with Restricted Fragment Length Polymorphisms. While it was first thought that the fertilisation rate was quite low, it was confirmed that the fertilisation rate is similar to other eucalypt species. The zygote abortion rate was quite high in one clone, but one wild tree had a similar seed production rate to other eucalypt species. The zygote and endosperm appeared to be different in the clone and the wild tree observed. The level of seed production was examined in clones and wild trees and it was found that the level was often quite low, particularly in the clones (0 13% in clones, 0 18% in wild trees) in comparison with other Eucalyptus species, and varied between genotypes. The use of a growth retardant such as paclobutrazol may increase the production of viable seed, if it is applied during autumn. The results were inconclusive for the fertiliser/paclobutrazol experiment, since the paclobutrazol was applied during spring which was the worst time of year for increasing seed production. There were differences between genotypes in reaction to both the paclobutrazol and the fertiliser/paclobutrazol. Genetic diversity was moderate in comparison with other Eucalyptus species, and there was a low level of genetic differentiation between populations in the nuclear genome. No differentiation was observed between the morphologically recognised subspecies in the nuclear genome, but differentiation between the populations on the Swan Coastal Plain and populations on the Darling Plateau was seen in the chloroplast genome, indicating that there was historical separation of these two areas. The conclusions arising from this work are that while controlled pollinations are possible in Eucalyptus marginata the clones that were used in these experiments have often behaved differently to the wild trees in the time of anthesis and levels of viable seed production, and in one clone (5J119) the zygote and endosperm nuclei appeared to be very different to the zygote and endosperm nuclei of a wild tree. Further investigation is necessary to see if these differences are related to the low level of seed production observed in the clonal populations. Paclobutrazol may be worth exploring further as a means of increasing seed production. Material to be used for rehabilitation and seed orchards can be collected from a wide area in the main distribution of the species, although trees on the Swan Coastal Plain are distinct from the trees in the main forest area in the chloroplast genome.

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Cossiello, Raquel Di Falco. "Efeito de quatro diferentes meios de cultura na qualidade morfologica de zigotos e embriões." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/308505.

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Orientador: Carlos Alberto Petta
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-14T05:22:09Z (GMT). No. of bitstreams: 1 Cossiello_RaquelDiFalco.pdf: 3774222 bytes, checksum: 96b4cbfa6f25f58d8240f552b5c83617 (MD5) Previous issue date: 2009
Resumo: Objetivo: comparar os efeitos de quatro diferentes meios de cultura na morfologia dos zigotos e embriões. Materiais e métodos: estudo retrospectivo conduzido no Centro de Reprodução Humana de Campinas, em que 2.289 embriões de 319 ciclos de ICSI foram avaliados de setembro de 2006 a setembro de 2008. O protocolo longo foi usado para estimulação ovariana em todos os casos. Todos os oócitos foram cultivados em dois meios diferentes. O meio HTF (Irvine Scientific) foi usado como meio-padrão, enquanto que os meios Universal IVF Médium (Medicult), Global (LifeGlobal) e IVF-30 (Vitrolife) foram usados como secundários. A separação dos oócitos em meios diferentes foi realizada alternadamente após ICSI. A presença e a posição de pronúcleos e Nuclear Precusror Bodies (NPBs) foram checadas 18 a 20 horas após ICSI. Baseado na classificação descrita por Gianaroli et al., os zigotos foram identificados como: (A1) pronúcleos justapostos e centralizados com NPBs grandes e alinhados; (A2) pronúcleos justapostos e centralizados com NPBs grandes e dispersos. Os embriões foram avaliados 44 a 46 horas após ICSI, de acordo com o número de blastômeros, porcentagem de fragmentação e multinucleação. Os embriões considerados top apresentaram quatro blastômeros regulares, fragmentação menor que 20% do volume embrionário e blastômeros não multinucleados. Para a análise dos dados foram utilizados Z-test, odds ratio simples e múltiplo através de regressão logística com seu respectivo intervalo de confiança a 95%. Resultados: quando a classificação dos zigotos foi analisada, o meio IVF-30 mostrou maior porcentagem (55,2%) de zigotos A1+A2, em relação ao HTF, Global e Universal IVF Medium (49,1%, 44,7% e 44,2%, respectivamente). A porcentagem de embriões top foi significativamente maior no meio Global (40,4%) comparado com HTF (21,1%), IVF-30 (25,0%) e Universal IVF Medium (11,1%). No segundo dia de desenvolvimento, Medicult produziu mais embriões com três células em relação aos outros meios que produziram mais embriões com quatro células. Conclusão: Houve diferenças significativas entre os quatro meios de cultura sobre a morfologia dos zigotos e a morfologia embrionária. IVF-30 (Vitrolife) resultou em maior número de zigotos com pronúcleos centralizados e nucléolos justapostos e dispersos. Global (LifeGlobal) sustentou maior formação de embriões top no dia 2 e maiores taxas de clivagem em relação aos demais meios
Abstract: Objective: compare the effects of four different culture media on the quality of zygotes and embryos. Methods: This retrospective study, performed at the Center for Human Reproduction of Campinas-Brazil analyzed 2289 embryos were assessed from September 2006 to September 2008. Long protocol was used for ovarian stimulation in all cases. The oocytes of each patient were cultivated in two different culture media. The medium HTF - Irvine was set as the default for all cycles and IVF Medium - Medicult, GGG 20 - Global and IVF 30 - Vitrolife defined as secondary media. The sibling oocytes were divided in the two culture media after ICSI. The confirmation of fertilization and classification as described by Gianaroli were evaluated 18-20 hours after ICSI. On the second day (day 2) of development, the embryos were evaluated according the number of cells, percentage of fragmentation and number of nuclei. On day 2, the embryos that had four cells with less than 20% of fragmentation and were mononucleated embryos were classified as Top. Z-test and Odds ratios were used for statistical analysis. Results: IVF-30 showed a higher percentage (55.2) of zygotes A1 + A2 when compared to HTF, Global and Universal IVF Medium media (49.1%; 44.7%; 44.2% respectively) The percentage of Top embryos was significantly higher in Global medium (40.4%) compared to HTF (21.1%), IVF-30 (25.0%) and Universal IVF medium (11.1%). On day 2 Universal IVF Medium produced more embryos with three blastomeres when compared to other media that produced more embryos with four blastomeres. Conclusions: The use of IVF- 30 medium resulted in a higher number of zygotes with centralized pronuclei with juxtaposed or scattered nucleoli. Meanwhile, Global medium produced a greater number of morphologically good embryos (TOP) and higher cleavage rate on the second day of development
Universidade Estadual de Campi
Tocoginecologia
Mestre em Tocoginecologia

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Jo, Kyoung Ha Jo. "The sperm centrioles have unique structures and require poc1 for proper formation in Drosophila melanogaster." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1543408971319716.

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Fishman, Emily Lillian. "The Atypical Centriole of Human and Beetle Sperm." University of Toledo / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1556808522272757.

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Boyen, Catherine. "Etude de la paroi cellulaire des pheophycees : approche physicochimique et immunocytologique, preparation d'enzymes de degradation specifiques." Paris 6, 1987. http://www.theses.fr/1987PA066281.

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Etude de la composition osidique d'alginate des genres pelvetia, fucus, arcophyllum, sargassum et laminaria. Preparation et caracterisation des alginates-lyases a partir de divers mollusques marins et d'une bacterie marine. Etude comparee de la regeneration de la paroi du protoplaste et de la mise en place normale de la paroi du zygote de fucus distichus par marquage avec des anticorps monoclonaux

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Arroyo, Cardona Gemma. "Valoració de la qualitat en els primers estadis de desenvolupament embrionari humà." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/322799.

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La selecció embrionària i la capacitat de predir el potencial d’implantació dels embrions humans és un factor determinant per l’èxit de les tècniques de fecundació in vitro (FIV), que permet reduir el número d’embrions a transferir minimitzant el risc d’embaràs múltiple. La pràctica més habitual per valorar la qualitat embrionària i dur a terme la selecció es basa en criteris morfològics i observacions en dia 1 (fecundació i divisió primerenca), dia 2 i 3 (divisió i fragmentació dels blastòmers) i en dia 5, o combinacions d’aquestes. Allargar el cultiu fins a blastocist, així com la determinació de la seva dotació cromosòmica, sembla una bona opció per seleccionar els embrions de millor qualitat, però malauradament no totes les pacients són bones candidates d’aquesta estratègia. El patró pronuclear s’ha associat amb el desenvolupament embrionari. En alguns països només poden criopreservar embrions fins a aquest estadi i per això n’és important la classificació. El nostre objectiu ha estat correlacionar la morfologia embrionària del zigot a l’estadi de 2 PN amb la utilització de les classificacions de pronuclis de Tesarik i Greco, 1999 (p0-5) i Scott et al., 2000 (z1-4), i la primera divisió embrionària a les 26h (EC), amb la morfologia de l’embrió en estadis posteriors de desenvolupament i la seva dotació cromosòmica. Primerament hem correlacionat els patrons de pronuclis (PN) amb la morfologia del zigot i de l’embrió. A l’utilitzar les classificacions de PN, hem observat una associació entre la sincronia en la polarització dels precursors nucleolars (NPB) i la bona qualitat embrionària. El patró p4 associat a un baix número de NPB s’ha correlacionat amb embrions multinucleats i embrions de baixa qualitat. No hi ha diferències en la taxa d’embaràs quan s’ha transferit al menys un embrió provinent d’un bon patró de PN o no. Per tal d’analitzar la relació entre la morfologia del zigot en 2PN segons les dues classificacions de PN i la dotació cromosòmica de l’embrió, s’han analitzat els embrions de 73 cicles de diagnòstic genètic preimplantacional (PGD) i cribatge d’aneuploïdies (PGS). No hi ha relació entre els patrons de PN i la dotació cromosòmica. No hem trobat correlació entre els PN i la morfologia embrionària. No hi ha relació entre euploïdia i qualitat embrionària, però sí quan distingim entre euploïdia, aneuploïdia i poliploïdia. El segon objectiu ha estat analitzar la correlació entre la divisió primerenca dels zigots i la qualitat embrionària i la dotació cromosòmica. S’han analitzat 595 embrions de 96 cicles de PGD/PGS. Hi ha diferències estadísticament significatives en la taxa d’embaràs per transferència quan s’ha transferit al menys un embrió EC o no. També hi ha diferències entre embrions EC, No PN o 2PN encara visibles a les 26h i la qualitat embrionària en dia 2 i la taxa de blastocist en PGS; no és així en PGD. En PGS i en PGD, els embrions EC tenen menys anomalies cromosòmiques que els embrions No PN i 2PN. Finalment, veiem que la valoració seqüencial de la morfologia oocitària, classificació de PN i morfologia embrionària permet seleccionar millor els embrions a transferir. Malgrat tot, en un programa de PGD/PGS la classificació de PN no pot predir ni la qualitat ni la dotació cromosòmica embrionària. Pel que fa la divisió primerenca, s’ha vist que està correlacionat amb la qualitat embrionària, el desenvolupament fins a blastocist i la dotació cromosòmica de l’embrió.
Several strategies have been proposed for the selection of embryos for uterine transfer in human assisted reproduction. The possibility of choosing adequate embryos with high implantation potential will allow the reduction in the number of embryos transferred. This will lead to a decrease in the percentage of multiple pregnancies and its complications. The scoring criteria of embryo selection are based on serial morphological observations conducted on day 1 (during the assessment of fertilization and early cleavage), on days 2 and 3 (based on cleavage and blastomere fragmentation), on day 5, or on combinations of these criteria. Extending the culture of embryos to the blastocyst stage may also be a good option to select high quality embryos, as well as the determination of the chromosome constitution of the embryo. Unfortunately, not all cases are good candidates and benefit from extended culture. Pronuclear morphology assessment has been extensively described as a method to score zygotes. Also, some countries are only allowed to freeze zygotes and the selection of embryos at this stage is thus necessary. The objective was to evaluate the usefulness of pronuclear patterns as described by Tesarik and Greco, 1999 (patterns p 0-5) and Scott et al., 2000 (Z1-4) as well as the occurrence of early cleavage at 26h as predictors of embryo morphology, implantation potential and chromosome constitution. The first purpose was to relate pronuclear patterns (PN) and zygote cytoplasmic appearance and embryo morphology. On this sense, the usefulness of PN classifications for embryo selection was assessed. We observed that synchrony on polarization and number of nucleolar precursor bodies (NPB) were associated with good quality embryos. Pattern 4 zygotes were associated with small number of NPB developed into multinucleated embryos and poor quality embryos. No significant differences were found in the pregnancy rate between transfer of at least one good prognosis PN pattern and transfer of poor prognosis PN patterns. In order to evaluate the usefulness of pronuclear patterns as predictors of embryo chromosome constitution, up to 73 preimplantation genetic diagnosis/preimplantation genetic screening (PGD/PGS) cycles were analysed. The results show that the PN pattern using Tesarik’s and Scott’s classification systems is not related to the embryo developmental potential or its chromosome constitution. As regard to the relationship between PN pattern and embryo quality, the data obtained in the second study showed no correlation between both parameters. Although there were no significant differences when comparing the distribution of chromosomally normal and abnormal embryos with respect to embryo quality, such differences were observed when distinguishing between normal, aneuploid and polyploid embryos. The second objective was to analyse the correlation between early cleavage and embryo quality and chromosome constitution including 595 embryos from 96 PGS/PGD cycles. When clinical pregnancy rates per transfer were compared, statistically significant differences were observed between patients that had at least one early cleavage embryo and patients no EC. Statistically significant differences were found between EC, No PN and 2PN embryos at 26 h, good embryo quality at day 2 and in blastocyst rate in PGS cycles. These differences were not found in the PGD group. Early cleaved embryos exhibited less chromosome abnormalities than No PN and 2PN group in PGS and in PGD group. In conclusion, sequential assessment involving the evaluation of oocyte quality, the classification of PN patterns and embryo morphology allows a more accurate evaluation of embryos to be selected for transfer. Therefore, in the context of a PGD/PGS programme, the PN pattern cannot be used as a tool to predict embryo quality or chromosome status. Early cleavage has shown to correlate with embryo quality, with the capacity to develop up to blastocyst stage, as well as with euploid chromosome constitution.

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Paspuleti, Sreelatha. "Isolation and Identification of O-linked-β-N-acetylglucosamine Modified Proteins (O-GlcNAc) in the Developing Xenopus laevis Oocyte." Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/809.

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Oocyte development in Xenopus laevis spans six morphologically distinct stages (stage I-VI), and is associated with a decrease in protein O-GlcNAc levels. As a first step in elucidating the role of O-GlcNAc in developing oocytes, initial efforts were focused on isolation and identification of fifteen modified proteins that decrease during oocyte development. Stage I oocytes due to their high amounts of these proteins, were used as starting material for purification. Multiple affinity and specific antibody based purification technique were initially used in an attempt to enrich the O-GlcNAc proteins. Due to the unique properties of the proteins ultimately identified, these techniques were unable to provide sufficient material for sequencing. However, differential centrifugation coupled with 2D-gel electrophoresis was highly successful. The majority of isolated proteins were strongly basic in nature with pIs 8-10. Coomassie stained bands from 2D-analysis were trypsin digested, and peptides were sequenced by mass spectroscopy (Finnigan LCQ). Mass data were interpreted by Bioworks software, and protein sequences were compared to multiple protein databases. Initially, six proteins were identified as Thesaurin a (42Sp50), cytoplasmic mRNA binding protein p54, y-box homolog, Xp 54 (ATP dependent RNA helicase p54), Vg1 RNA binding protein variant A, Zygote arrest 1(Zar1) and Poly (A) binding protein (PABP). Thesaurin a, the main component of 42S particle of previtellogenic oocytes (stages I-III) is involved in tRNA storage and possess low tRNA transfer activity; y-box factor homolog and Xp54 are present in oocyte mRNA storage ribonucleoprotein particles; Vg1 RBP variant A associates mVg1 RNA to microtubules in order to translocate to the vegetal cortex; Zar1 is involved in oocyte-to-embryo transition; and PABP initiates mRNA translation. This study is the first to characterize these oocyte specific proteins as O-GlcNAc modified proteins. Overall, the presence of several O-GlcNAc proteins in oocytes, the reduction in their levels/ O-GlcNAc levels, and the variation in maturation time in the presence of HBP-flux modulators in developing oocyte indicates O-GlcNAc may play important roles in metabolism, cell growth and cell division of X. laevis oocytes. Therefore, identifying the remainder of these proteins and elucidating the O-GlcNAc role in their function is a worthwhile pursuit.

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Raveux, Aurélien. "In vivo exploration of the impact of ribosome biogenesis alterations on intestinal homeostasis and tumorigenesis in the adult mouse." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS517.

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La biogenèse des ribosomes est un processus cellulaire essentiel. Des altérations de ce processus induisent une forte activation de p53 et d’autres voies de surveillance encore mal connues, auxquelles les cellules tumorales semblent particulièrement sensibles in vitro. L’inhibition de la synthèse des ribosomes constitue ainsi une stratégie prometteuse pour lutter contre le cancer. L’inactivation conditionnelle du facteur de biogenèse des ribosomes Notchless (Nle) dans l’intestin de souris adulte conduit à l’élimination rapide des cellules souches et des progéniteurs intestinaux. Au cours de ma thèse, j’ai complété l’étude de ce phénotype en montrant que cette élimination a lieu sans altération détectable de la synthèse protéique, et que, bien que principalement médié par l’activation de p53, l’arrêt du cycle cellulaire dans les cryptes, est indépendant de p21. De plus, afin d’évaluer l’impact d’altérations de la biogenèse des ribosomes sur la tumorigenèse intestinale, j’ai analysé les conséquences de la perte de fonction de Nle sur l’initiation tumorale consécutive à la délétion du gène Apc. Cette expérience a révélé que, bien que la perte de fonction de Nle réduise le phénotype hyperprolifératif, la perte de fonction d’Apc améliore la résistance des cellules souches et des progéniteurs aux défauts de biogenèse des ribosomes. Nos résultats questionnent la pertinence des stratégies thérapeutiques basées sur l’inhibition de la synthèse des ribosomes dans le cas du cancer colorectal. Plus généralement, ces travaux mettent en évidence des interactions complexes entre la voie de signalisation Wnt et la voie de biogenèse des ribosomes in vivo
Ribosome biogenesis is an essential cellular process. Its alteration results in a strong activation of p53 and of other ribosome biogenesis surveillance pathways that remain to be identified. In vitro studies have shown that cancer cells display an enhanced sensitivity to ribosome biogenesis inhibition, indicating that targeting ribosome production would be a promising strategy for the development of new treatments. Conditional inactivation of the ribosome biogenesis factor Notchless (Nle) in the adult mouse intestine leads to the rapid elimination of intestinal stem cells and progenitors. During my thesis, I completed the study of this phenotype. I have shown that this elimination occurred in the absence of detectable alterations in protein synthesis, and that, while it was primarily mediated by p53, cell cycle arrest in the intestinal crypts was independent of p21. Moreover, to assess the impact of ribosome biogenesis alterations on intestinal tumorigenesis, I monitored the consequences of Nle loss-of-function on tumor initiation following Apc deletion. This study revealed that, though Nle loss-of-function attenuates proliferative compartment expansion, Apc deficiency improves stem cell and progenitor resistance to ribosome biogenesis defects. Our results thus alert on possible limitations of ribosome biogenesis inhibition-based therapeutic strategies in the context of colorectal cancer. More generally, this work hints towards complex interactions between the Wnt signaling pathway and the ribosome biogenesis pathway in vivo

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Ganesh, Sravya. "Dlouhé nekódující RNA během přeměny vajíčka na embryo." Doctoral thesis, 2018. http://www.nusl.cz/ntk/nusl-391390.

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(English) Oocyte-to-embryo transition (OET) is one of the most complex developmental events, during which a differentiated oocyte gives rise to a totipotent zygote. During OET a transcriptionally silent oocyte undergoes massive reprogramming of gene expression, which transforms it into a transcriptionally active zygote. Although numerous studies have contributed to understanding the mechanism of OET, many genes involved in OET are yet to be identified. A whole new level of possible regulation of OET came with the discovery of long non-coding RNAs (lncRNA). LncRNAs are pol II transcripts longer than 200 nucleotides, that are typically spliced and polyadenylated but do not encode proteins. While lncRNAs have been studied in many model systems including embryonic stem cells, their expression in oocytes and early embryos and contribution to OET were largely unexplored at the beginning of this project. In my PhD project, I aimed to identify, annotate, and analyze lncRNAs expressed during OET. First, using RNA-Seq, 1600 highly reliable lncRNAs were identified and annotated in mouse oocytes and early embryos. Majority of lncRNAs were novel with expression exclusively at OET stages. A significant fraction of these lncRNAs was found associated with LTR retrotransposons, contributing to their novelty and...

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Moravec, Martin. "Analýza pluripotentního programu genové exprese v časných embryích a embryonálních kmenových buňkách." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-310881.

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Pluripotence je schopnost buňky diferencovat do jakéhokoliv buněčného typu. Formuje se během časného embryonálního vývoje u savců a její vznik je spojen s reprogramací genové exprese na globální úrovni. Proces přirozeného vzniku pluripotence není stále zcela pochopen. Pro získání nového pohledu na události, které vedou ke vzniku pluripotence u savců, studovali jsme změny v genové expresi během oocyt-zygotického přechodu u myši. V tomto modelovém systému, oplodněné vajíčko podstoupí reprogramaci, která vede k vytvoření pluripotentních blastomer. Tyto blastomery zakládají samotné embryo. Cílem mé diplomové práce bylo analyzovat aktivaci transkripce během časného vývoje a vyvinout metodu pro monitorování exprese genů v oocytech, časných embryích a embryonálních kmenových buňkách. Metoda využívá kvantitativní PCR a umožnuje změřit expresi až 48 vybraných genů, které slouží jako markery pro maternální degradaci, aktivaci pluripotentního programu a diferenciaci do zárodečných linií. Dále ukazujeme, že náš systém monitoruje dynamiku transkriptomu během oocyt-zygotického přechodu, a získané výsledky jsou srovnatelné s daty naměřenými pomocí jiných metod. Díky našemu bioinformatickému přístupu jsme navíc identifikovali nové oocyt-specifické a zygotické nekódující RNA. Klíčová slova: pluripotence,...

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Ussishkin, Adam. "Target = myteʔ (nonword); prime = zygem (nonword)." 2011. http://hdl.handle.net/10150/344724.

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Jordan, Shawn. "The molecular regulation of cytokinesis in the Caenorhabditis elegans zygote." Thesis, 2015. https://doi.org/10.7916/D8P849ZS.

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The division of one cell to form two cells, or cytokinesis, is fundamental to the development of all known multi-cellular organisms, as well as the propagation of life between generations. The intracellular mechanisms that mediate the physical deformation of the cell membrane during division have proven to be remarkably robust, with multiple processes functioning together to achieve bisection. Here, I present my doctoral work, which seeks to illuminate the dynamic molecular interplay that coordinates and drives cytokinesis in the Caenorhabditis elegans single-cell zygote. In Chapter 1, I begin with an introduction on cytokinesis and the many proteins known to regulate cell division. Chapter 2 presents a detailed review of three intracellular signaling molecules that mediate the spatial control of cytokinesis, known as Rho family small GTPases. In Chapter 3, I present work in which we inactivated specific cytokinesis protein functions at precise stages of the division process, in order to map out the first “temporal atlas” of essential cytokinetic functions. In Chapter 4, I present evidence that the GTPase CDC-42 and the cortical polarity machinery sequester cytokinesis-inhibiting proteins away from the division plane and protect the fidelity of cytokinesis. Chapter 5 lays out preliminary evidence that another GTPase, RAC-1, is a suppresser of cytokinesis and must be inactivated in the division plane specifically by a spindle-associated regulatory protein. Through this body of work, I have attempted to elucidate the underpinnings of the complex intracellular orchestra that drives cytokinesis. This work provides valuable insight, not only into how this vital process occurs, but also how the disruption of its components could lead to the development of complex diseases like cancer.

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Pichrtová, Martina. "Stresová odolnost polárních hydro-terestrických řas Zygnema spp. (Zygnematophyceae, Streptophyta)." Doctoral thesis, 2014. http://www.nusl.cz/ntk/nusl-338454.

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Filamentous green microalgae of the genus Zygnema belong to the most common primary producers in the polar hydro-terrestrial environment. In such unstable habitats, organisms are subject to various stress factors, e.g., freeze-thaw cycles, desiccation and high irradiation levels. However, the stress resistance mechanisms that enable Zygnema spp. to thrive in this extreme environment are only partially understood. Therefore, polar Zygnema spp. were examined under various stress conditions using both field samples and cultures. Moreover, molecular phylogeny methods were applied that provided first insights into the diversity of polar Zygnema. Sequencing of the chloroplast gene rbcL revealed several different Zygnema genotypes and, surprisingly, one Zygnemopsis sp. with vegetative Zygnema sp. morphology. First set of experiments examined the effects of UV exposure. It turned out that polar strains of Zygnema produce phenolic substances as UV screens. These substances are most likely stored in vacuoles and other vesicles at the cell periphery, providing protection for other organelles. In the next study, Zygnema spp. were investigated under natural conditions in the Arctic. At the end of summer, the cells gradually lose their typical vegetative appearance (with large vacuoles and stellate chloroplasts)...

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Ya-LingHuang and 黃雅鈴. "The Bioactivity Study of Zygote Extract from Taiwan Epinephelus Lanceolatus." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/92663060999738636146.

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碩士
國立成功大學
化學系
102
Taiwan Epinephelus Lanceolatus is a high economic-valued, high production cultured fish species. In the last decade, the farming technique of Taiwan Epinephelus Lanceolatus has been improved and shown a steady production. Taiwan Epinephelus Lanceolatus is the biggest cultured fish with high amount of proteins. In this study the bioactivity of the zygote extract, the hydrolyzed proteins were assayed the antioxidant activity and the extract without enzymatic hydrolysis and with the molecular weight under 5 kDa was tested and used as cosmetic component. We use FPLC to measure the hydrolyzed peptide molecule weight and found that hydrolyzed zygote extract showing molecular weight under 12500 Da after enzymatic hydrolysis by papain enzyme and bromelain for 12 hours. And it showed that papain exhibited higher antioxidant activity than bromelain with IC50 of 0.17687 mg∕ml versus 0.9055 mg∕ml. Interestingly, bromelain hydrolyzed peptides showed higher reduction ability than papain hydrolyzed peptides toward reducing Fe3+ (Prussian Blue test ). The extracts of zygote of Taiwan Epinephelus Lanceolatus without enzymatic hydrolysis and with the molecular weight lower than 5 kDa showed the activity to reduce the melanin spots after one week test. And it also showed the activity to enhance the moisture ability. These results showed that the extract without enzymatic hydrolysis and with molecular weight lower than 5 kDa is a good cosmetic source.

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Sumner, Michael J. "Ovule development and zygote formation in Brassica campestris L. cv. Candle." 1987. http://hdl.handle.net/1993/24207.

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Lin, William, and 林殿威. "Analysis of mouse 2-cell stage zygote-specific granzyme G gene express profile." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/13468024072576690646.

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碩士
國立中興大學
生物化學研究所
89
The purpose of this study was to identify genes expressed in the different developmental stage of mouse embryo after onset of their oestrus. Total RNA samples were extracted from ICR mouse fertilized eggs, which had been induced to super-ovulation by administration of gonadotrophins, at various time at 24, 48 and 72 post-hCG injection. Each RNA samples was subjected to analysis by method of differential display reverse transcription-polymerase chain reaction (DDRT-PCR) with a total of 40 primer sets comprised of anchor and arbitrary primers. One of these clones, expressed at 48h post-hCG injection, was possess a sequence 100% homology to that of gene coding for the serine protease, granzyme G. Granzymes family (granzyme A-H,K,M) are serine proteases present in secretory granules of cytolytic T lymphocyte lines. Granzyme D-G showed to be expressed in late gestation at mouse uterus. There is no report about granzyme G expressed so early, 2-cell stage, at mouse embryo. It is interesting that any gene expression in pre-implantation embryo may involve in the initiated of embryonic genomic DNA. Granzyme G could the one of whose “pull the trigger” to help mouse embryo development continually. We used the microinjection of morpholino antisense oligos into the two pro-nucleus(2PN) stage embryo to block the expressing of granzyme G, compared with culture medium injected, standard control oligo injected and in vitro culture without any treatment. This antisense oligo treatment will be disclose the granzyme G that involved in possibly functions of the early development of mouse embryos

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Kuan-TingWang and 汪冠廷. "The Bioactivity Study of the Zygote Extract from Epinephelus Lanceolatus after Incubation with Lactobacillus." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/bk84um.

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Chang, Chiu-Ping, and 張秋萍. "A Study on Learning Effect of Health Education in Sixth Grade with Zygote Body." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/76405483004488787422.

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碩士
亞洲大學
資訊工程學系碩士在職專班
103
The purpose of this study aims at integrating the 3D technology “ZYGOTE BODY” into Health Education and assessing its effectiveness. The subject of the health lessons are for sixth graders who are gradually reaching puberty. When facing the key moment of both physical and mental changes, students need to learn some crucial lessons about themselves, such as how to correctly recognize and accept their own bodies in a sound mind, understanding how the opposite sex think, mutual respect between two sexes, and self-protection. Health Education provides an easy access to the above-mentioned knowledge. Nevertheless, with the limited contents of the textbook, students hardly have the chance to see the internal organs they have often heard of. They are curious about these organs which sound familiar but yet are actually strange to them.Thus, in this theme-based instruction called “Get to Know My Body Better”, a self-compiled teaching material is adopted. Different from applying the conventional flat posters as teaching aids, the study employs browsers of 3-dimensional models of human bodies in Health Education for six graders. The result of the study shows that applying ZYGOTE BODY in class helps to enhance their motivation to learn compared with using conventional posters. Besides, students’ learning effect has elevated as well. However, Health Education is often considered to be a minor subject and can be easily under-estimated because of the emphasis of academic subjects and the indifference from the school authorities. To sum up, being healthy is one of the fundamental human rights which people shouldn’t be deprived of. It is essential to strive for conducting a normal and effective instruction in Health Education.

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Teixeira, Sérgio Ricardo Brandão. "O Zygote Body no ensino do anatomia do corpo humano : um estudo de caso." Master's thesis, 2013. http://hdl.handle.net/10400.8/1975.

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Kräußling, Michael. "Analysis on division patterns and transcriptional activity in embryos from medaka "Oryzias latipes" before the midblastula transition." Doctoral thesis, 2011. https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-66911.

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Das Studium der Entwicklung von Tieren ist eine der ältesten Disziplinen in der Biologie. Die gesammelten Daten von unzähligen Untersuchungen an den verschiedensten Spezies wurden dazu benutzt, um ein generelles Verständnis des tierischen Lebenszykluses zu formulieren. Ein wichtiges Ergebnis der intensiven Untersuchungen war vor etwa einem Jahrhundert die Entdeckung spezifischer morphologischer Veränderungen, die sich während der Teilungsphase, der Zeitperiode die der Befruchtung und Aktivierung des Eies am Anfang der Embryogenese folgt, vollziehen. Diese Befunde führten schlussendlich zur Formulierung des Konzepts einer „Mid-Blastula Transition“ (MBT). Bisher gibt es nur eine Theorie die die Regulierung der MBT in befriedigender Weise erklärt. Dies ist das Model des Kern/Plasma-Verhältnis, welches sich aus dem Verhältnis DNA-Menge zu Zytoplasmavolumen ableitet. Es erklärt die MBT-Aktivierung durch bisher unbekannte, maternal deponierte Faktoren im Ei, welche die MBT Aktivierung kontrollieren, deren Konzentration allerdings mit jeder Zellteilung verdünnt wird, bis sie schließlich ihre blockierende Funktion verloren haben. Zwar wurde die Existenz dieses Mechanismuses schon in zahlreichen Spezies experimentell bewiesen, allerdings bleibt er nur eine ungenaue Beschreibung der ablaufenden Prozesse und lässt weiterhin viele Fragen unbeantwortet. Vor diesem Hintergrund hat diese Arbeit gezeigt, dass die Zellzyklen in Embryonen von Medaka (Oryzias latipes) ihre Synchronität schon nach dem vierten oder fünften Teilung verlieren, und diese durch ein Teilungsmuster ersetzt wird, das als „metasynchron“ bezeichnet wird. In diesem Teilungsmuster verlaufen die Zellteilungen in Wellen, die im Zentrum des Embryos beginnen und sich von dort nach außen hin radial ausbreiten. Noch ist der Sinn einer auf diese Art verlaufenden Zellteilung unbekannt, auch wenn es verschiedene Theorien gibt die versuchen den zugrunde liegenden Mechanismus zu erklären. Allen voran steht die Theorie eines unterschiedlichen Zugangs zu Faktoren innerhalb des Dotters. Allerdings wird diese Theorie durch die Beobachtungen in verformten Embryonen wiederlegt, in denen sich die Teilungswellen von einer Seite des Embryos zur gegenüberliegenden Seite ausgebreitet haben. Somit bleibt der Mechanismus für diese Art der Zellteilung weiterhin unklar. Nicht zu vergessen ist, dass diese deformierten Embryonen eine der möglichen Konsequenzen asymmetrischer Furchung während einer frühen Zellteilung sind. Asymmetrische Teilungen treten in Medaka in einer erheblichen Anzahl von Embryonen auf und haben einen direkten Einfluss auf die gleichmäßige Verteilung des Zytoplasma. Leider war es nicht möglich die Auswirkungen einer solchen ungleichmäßigen Verteilung aufzudecken, auch wenn man davon ausgehen kann, dass ein ausreichend großes Ungleichgewicht zu unterschiedlichen Zeitpunkten der MBT-Aktivierung in verschiedenen Zellgruppen führen müsste. Ähnliche Beobachtungen wurden bereits in anderen Spezies gemacht, und es wurde vermutet, dass diese in ungleichmäßigen Zellteilungen begründet lagen. Weiterhin wurde bewiesen, dass die zygotische Transkription schon wesentlich vor dem bisher angenommenen frühesten Zeitpunkt aktiv ist. Darüber hinaus wurden Hinweise gefunden, die darauf hindeuten, dass die Transkription in Embryonen von Medaka in zwei Schritten einsetzt. Der erste Zeitpunkt ist das 16-Zellen-Stadium, in dem die ersten Zellen identifiziert wurden, die Phosphorylierung für RNAPII zeigten, und der zweite das64-Zellen Stadium, in dem der Anteil an p-RNAPII positiven Zellen signifikant anstieg. Ein schrittweiser Anstieg der Transkription wurde bereits in anderen Spezies beobachtet, auch wenn in diesen Fällen nur eine Erhöhung der mRNA-Menge festgestellt wurde, und nicht die unterschiedliche Anzahl an transkriptionell aktiven Zellen untersucht wurde.Zusammenfassend bestätigen und erweitern die hier gezeigten Daten die grundliegenden Kenntnisse über die Prozesse vor und währen der MBT, liefern darüber hinaus aber auch Anzeichen für viele Prozesse vor und während der MBT, die nur wenig oder gar nicht verstanden sind
The study of animal development is one of the oldest disciplines in the field of biology and the collected data from countless investigations on numerous species have formed a general understanding of the animal life-cycle. Almost one century ago, one consequence of these intense investigations was the discovery of specific morphological changes that occur during the cleavage phase, a period that follows fertilization and egg activation at the very beginning of animal embryogenesis. These observations resulted into the formulation of the concept of a midblastula transition (MBT). So far, the mechanism of the nucleo-cytoplasmic ratio model is the only one that explains MBT regulation in a satisfying way. It suggests that the MBT is controlled by several maternal repressive factors in the egg, which are titrated out by every cell division until they lose their repressing potential. Although this regulatory mechanism was proven for several species and in different approaches, it is still only a rudimentary model for MBT control and leaves numerous questions unanswered. On this conceptual background, this thesis has shown that embryos from the medaka fish (Oryzias latipes) lose their cell cycle synchrony already after the fourth or fifth round of cell divisions, and replace it by a metasynchronous divisions pattern, in which cell division occurs in clear waves beginning in the embryo's center. The reason for this change in division mode is still unknown, although several hypotheses were put forward, most notable a difference in yolk-access between cells. However, this theory was weakened by division waves that progressed from one embryonic pole to the opposing one, which were occasionally observed in deformed embryos, leaving the mechanism for this phenomenon furthermore unclear. Those deformed embryos were most likely the result of asymmetric cell divisions at very early stages, a phenomenon which occurred in a significant percentage of medaka embryos and which directly influenced the equal distribution of cytoplasmic material. It could not beuncovered what kind of effects this unequal distribution of cytoplasm exerted on the progression of embryonic development, but it can be argued that relevant differences in cell volumes could result in cell clusters that will enter MBT at different time points. Comparable observations were already made in other species and it was hypothesized that they were the direct results of early unequal cell cleavages. Finally, it was demonstrated that zygotic transcription in medaka embryos is activated prior to the hitherto assumed time of the first transcriptional initiation. Moreover, indications were found that strongly speak for a transcriptional activation that occurs in two steps; a first step at the 16-cell stage when first cells were identified positive for RNAPII phosphorylation, and a second step at the 64-cell stage, when the number of p-RNAPII positive cells significantly increased. A stepwise activation of zygotic transcription was already observed in other species, but only for the overall increasing amount of mRNAs and irrespective of the actual number of transcriptionally active cells within the embryos. .. Overall, these data confirm and expand the basic knowledge of pre-MBT embryos and about the MBT itself. Furthermore, they also suggest that many early processes in pre-MBT embryos are only rudimentarily understood or still totally unknown

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47

Chen-FenChang and 張振芬. "The bioactivity study of the zygote extract from Taiwan Epinephelus lanceolatus and its application on the cosmetic." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/04557515549064046786.

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You, Yu-bin, and 劉佑彬. "Study on the Performance of (Zygo)ZMI-1000." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/32400259995249582782.

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碩士
國立中興大學
機械工程學系
86
Due to Heterodyne Interferometr featuring reslution easily, Handlingimmediaely and accuratly,etc,the thesis is going to exert it in theMicropositioning System to track position by a piezoelectric actuator andthe Laser Cabration System to calibration the sensitivity of accelerometer.In the aspect of the Micrpositioning System to track postion by apiezolectric actuator,the thesis is going to respecively compare it ofitseffects when controlling through the trditional PID cotroller and sel-organizing controller.In the self-organizing controller,the speed ofbuildng up the rules table can be fater through the changes of learingspeed,and a better rules table can be obtined from the way,whichdistinguish when to stop modify rules table.And at the sametime,the Kp,Ki,Kd cofficient of PID controller can be seen.In the part of the Lasr Cabration Sysem to calibrat in the sensitiviy ofacceleromter,because the thesis adopts the heterodyne interferometer inthe calculating of vibration is tead of the cmmon used Fring CountingMethd,the calculatng speed will get faster and the resolution can behigher.

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Fisher, Matthew B. "Increased yield of DNA from dual enzyme differential extraction." Thesis, 2015. https://hdl.handle.net/2144/15216.

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Forensic analysis of deoxyribonucleic acid (DNA) represents an important facet of criminal investigations. DNA extraction, the first step in sample processing where DNA is released from biological samples and isolated, is crucial for subsequent analysis. Minimizing loss of DNA during extraction as well as ensuring complete lysis of DNA-containing cells are two factors that must be considered when choosing an extraction method. Extraction procedures that minimize sample transfers, specifically single-tube extractions, are ideal for minimizing DNA loss. A DNA extraction kit made by ZyGEM (Hamilton, New Zealand) incorporates the use of a recently characterized proteinase; EA-1 achieves a single-tube extraction that requires no further purification. However, research published on this method reported that the extraction was unable to release DNA from sperm cells. Sexual assault cases routinely require DNA to be extracted from sperm cells, thus the ZyGEM method would be unsuitable for treatment of such samples. It could, however, possibly be used as part of a differential extraction procedure for samples containing a mixture of epithelial cells and sperm cells. The initial step in a differential extraction is the preferential lysis of any non-sperm cells. The DNA from these cells is separated and removed from the intact sperm, which are then lysed using more robust methods. The current research discusses the process of differential extraction and the investigation of an alternative method for sperm cell lysis. Development of this method was aided by studying the physical structure of sperm cells. Sperm DNA is packaged by small proteins, the protamines that replace histones during spermiogenesis. These proteins are comprised primarily of the amino acids Arginine and Lysine. The serine proteinase Trypsin, which cleaves peptides at Arginine and Lysine, was investigated as an alternative enzyme for sperm lysis in a differential extraction procedure. A sperm cell extraction method with Trypsin was developed, using the forensicGEM extraction to purify the sample following lysis with Trypsin. This method was compared to an extraction of sperm with Qiagen QIAamp® DNA Investigator kit. The results show that the new method using Trypsin and ZyGEM yields between 4 and 12 times more DNA than the Qiagen method. When low template samples were extracted and amplified, the new method was able to generate a full profile while samples extracted with Qiagen lost over 80% of the profile due to low yield in the extraction. Analysis of Peak Height (PH) showed the new method had slightly lower peak heights compared to Qiagen when similar amounts of DNA were amplified, however Peak Height Ratio (PHR) was not reduced in the new method. The results indicate that a new extraction method using Trypsin and ZyGEM provides greater amounts of DNA from extractions of sperm cells and that the method should be further developed into a differential extraction protocol to aid in mixture sample processing.
2022-03-31

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Xu, Haifeng Jäger Gerd. "Messtechnische Untersuchungen von hochpräzisen Planflächen mit einem Zygo-Phasenschiebeinterferometer /." 2006. http://www.gbv.de/dms/ilmenau/abs/514285680xu.txt.

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Dissertations / Theses on the topic 'Zygoma'

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