Universidad de Buenos Aires Facultad de Ciencias...
Among Eutherian mammals, L. maximus shows many unusual reproductive traits such as a high ovulation rate and a process of selective embryo resorption that occurs during the first\nhalf of gestation. Despite the high ovulatory rate, a few 8 to 12 oocytes are fertilized and implanted, and just the emb...
Guardado en:
| Autor principal: | |
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| Otros Autores: | |
| Formato: | Tesis doctoral acceptedVersion |
| Lenguaje: | Español |
| Publicado: |
Universidad de Buenos Aires. Facultad de Ciencias Veterinarias
2018
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| Materias: | |
| Acceso en línea: | http://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=avaposgra&cl=CL1&d=HWA_5659 https://repositoriouba.sisbi.uba.ar/gsdl/collect/avaposgra/index/assoc/HWA_5659.dir/5659.PDF |
| Aporte de: |
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I28-R145-HWA_5659 |
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dspace |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-145 |
| collection |
Repositorio Digital de la Universidad de Buenos Aires (UBA) |
| language |
Español |
| orig_language_str_mv |
spa |
| topic |
L. maximus Reabsorción embrionaria selectiva Lagostomus maximun Implantación Reabsorción selectiva Ciencias Veterinarias |
| spellingShingle |
L. maximus Reabsorción embrionaria selectiva Lagostomus maximun Implantación Reabsorción selectiva Ciencias Veterinarias Giacchino, Mariela Universidad de Buenos Aires Facultad de Ciencias... |
| topic_facet |
L. maximus Reabsorción embrionaria selectiva Lagostomus maximun Implantación Reabsorción selectiva Ciencias Veterinarias |
| description |
Among Eutherian mammals, L. maximus shows many unusual reproductive traits such as a high ovulation rate and a process of selective embryo resorption that occurs during the first\nhalf of gestation. Despite the high ovulatory rate, a few 8 to 12 oocytes are fertilized and implanted, and just the embryos nearest to the cervix develop normally to term; the remaining embryos are resorbed. A balance between immunological Th1/Th2 processes\nbiased in favor of Th2 activity is needed for a successful gestation; prevalence of Th1\nprocesses is associated with fetal miscarriage. In domestic animals, 80% of embryo loss occurs at the peri-implantation period. Insufficient levels of uterine progesterone (P4) may\ninduce a considerable embryo loss. The aim of this investigation was to analyze the possible causes and mechanisms involved in the unusual embryo resorption process shown in L.\nmaximus and its relationship with immune response. In L. maximus decidualization and embryo resorption are found as two processes that occur in a diferred and reversed way along the uterine horn. The uterine area nearest the cervix showed the higher P4\nconcentration. The only embryo that is gestated to term showed the highest levels of P4 and\nestradiol (E2). This presence of high hormonal levels has its origin in the ascending trajectory of the uterine artery, a branch of iliac artery. During pregnancy, low levels of IL-10 were\nfound with a marked presence of IFN-? indicating an active Th1 immune response. Embryo\nresorption would be originated through apoptosis followed by necrosis, P4 levels being insufficient to trigger the immunoprotection of the embryo. The decrease of P4 during gestation would be responsible of embryo-harmful Th1 cytokine release. When pseudo\novulation takes place at mid-gestation, the formation of secondary CL induces a new rise of P4 which helps to rescue the only surviving foetus from resorption. In L. maximus, hormonal\nalterations during pregnancy induce changes in the immune system that generate the\nselective embryo resorption. Finally, the finding of penile spikes in males led to establish L. maximus as an ovulatory-induced species |
| author2 |
Vitullo, Alfredo Daniel |
| author_facet |
Vitullo, Alfredo Daniel Giacchino, Mariela |
| format |
Tesis doctoral Tesis doctoral acceptedVersion |
| author |
Giacchino, Mariela |
| author_sort |
Giacchino, Mariela |
| title |
Universidad de Buenos Aires Facultad de Ciencias... |
| title_short |
Universidad de Buenos Aires Facultad de Ciencias... |
| title_full |
Universidad de Buenos Aires Facultad de Ciencias... |
| title_fullStr |
Universidad de Buenos Aires Facultad de Ciencias... |
| title_full_unstemmed |
Universidad de Buenos Aires Facultad de Ciencias... |
| title_sort |
universidad de buenos aires facultad de ciencias... |
| publisher |
Universidad de Buenos Aires. Facultad de Ciencias Veterinarias |
| publishDate |
2018 |
| url |
http://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=avaposgra&cl=CL1&d=HWA_5659 https://repositoriouba.sisbi.uba.ar/gsdl/collect/avaposgra/index/assoc/HWA_5659.dir/5659.PDF |
| work_keys_str_mv |
AT giacchinomariela universidaddebuenosairesfacultaddeciencias AT giacchinomariela caracterizaciondelprocesodeimplantacionenlagostomusmaximusunmamiferoconpoliovulacionyreabsorcionselectiva |
| _version_ |
1824356452337188864 |
| spelling |
I28-R145-HWA_56592024-08-27 Universidad de Buenos Aires Facultad de Ciencias... Among Eutherian mammals, L. maximus shows many unusual reproductive traits such as a high ovulation rate and a process of selective embryo resorption that occurs during the first\nhalf of gestation. Despite the high ovulatory rate, a few 8 to 12 oocytes are fertilized and implanted, and just the embryos nearest to the cervix develop normally to term; the remaining embryos are resorbed. A balance between immunological Th1/Th2 processes\nbiased in favor of Th2 activity is needed for a successful gestation; prevalence of Th1\nprocesses is associated with fetal miscarriage. In domestic animals, 80% of embryo loss occurs at the peri-implantation period. Insufficient levels of uterine progesterone (P4) may\ninduce a considerable embryo loss. The aim of this investigation was to analyze the possible causes and mechanisms involved in the unusual embryo resorption process shown in L.\nmaximus and its relationship with immune response. In L. maximus decidualization and embryo resorption are found as two processes that occur in a diferred and reversed way along the uterine horn. The uterine area nearest the cervix showed the higher P4\nconcentration. The only embryo that is gestated to term showed the highest levels of P4 and\nestradiol (E2). This presence of high hormonal levels has its origin in the ascending trajectory of the uterine artery, a branch of iliac artery. During pregnancy, low levels of IL-10 were\nfound with a marked presence of IFN-? indicating an active Th1 immune response. Embryo\nresorption would be originated through apoptosis followed by necrosis, P4 levels being insufficient to trigger the immunoprotection of the embryo. The decrease of P4 during gestation would be responsible of embryo-harmful Th1 cytokine release. When pseudo\novulation takes place at mid-gestation, the formation of secondary CL induces a new rise of P4 which helps to rescue the only surviving foetus from resorption. In L. maximus, hormonal\nalterations during pregnancy induce changes in the immune system that generate the\nselective embryo resorption. Finally, the finding of penile spikes in males led to establish L. maximus as an ovulatory-induced species Fil: Giacchino, Mariela. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Buenos Aires, Argentina Vitullo, Alfredo Daniel Giacchino, Mariela 2018-04-20 L. maximus presenta características reproductivas inusuales en los mamíferos euterios como su elevada tasa de ovulación y un proceso de reabsorción embrionaria selectiva\ndurante la primera mitad de la preñez. A pesar de tener una alta tasa ovulatoria, sólo 8 a 12 oocitos son fecundados e implantados y el embrión más cercano al cérvix en cada cuerno\nuterino presenta un desarrollo normal; el resto sufre reabsorción. Una gestación exitosa\nrequiere un balance inmunológico Th1/Th2 inclinado hacia la actividad Th2; la prevalencia\nde Th1 se asocia con reabsorción fetal. En animales domésticos, el 80% de las pérdidas\nembrionarias ocurre durante el período de peri-implantación. La insuficiencia de\nprogesterona (P4) en circulación uterina podría generar una considerable pérdida de embriones. El objetivo de este trabajo fue analizar las posibles causas y mecanismos del\ninusual proceso de reabsorción embrionaria selectiva que presenta L. maximus y su\nvinculación con la respuesta inmunológica. En L. maximus la decidualización y la reabsorción se presentan como dos procesos que suceden de manera diferida y en sentido\ninverso a lo largo del cuerno uterino. El sector uterino más cercano al cérvix presentó mayor\nconcentración de P4. El único embrión que se gesta a término mostró mayores niveles de P4 y estrógeno (E2). La presencia de mayores niveles hormonales se debería a que la\narteria uterina, rama de la arteria ilíaca, tiene un trayecto ascendente. Durante la preñez se\nencontraron niveles bajos de IL-10 con marcada presencia de IFN-?, indicando una\nrespuesta Th1 activa. La reabsorción embrionaria estaría generada por apoptosis, seguida\nde necrosis. Los niveles de P4 podrían no ser suficientes para generar la inmunoprotección\nfetal. Ante el descenso de P4 durante la gestación, se daría la secreción de citocinas de Th1\nperjudiciales para el feto; al producirse la pseudoovulación durante la preñez, los cuerpos\nluteos accesorios producen un nuevo aumento de P4 salvando el único feto más cercano al cérvix. En L. maximus las alteraciones hormonales durante la preñez darían cambios en el\nsistema inmunológico generando como resultado final la reabsorción embrionaria selectiva.\nPor último, el hallazgo de espículas peneanas en L. maximus permitió establecer el probable caracter de ovulador inducido application/pdf L. maximus Reabsorción embrionaria selectiva spa Universidad de Buenos Aires. Facultad de Ciencias Veterinarias info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-ncnd/2.5/ar/ Lagostomus maximun Implantación Reabsorción selectiva Ciencias Veterinarias Doctora de la Universidad de Buenos Aires en Ciencias Veterinarias Caracterización del proceso de implantación en Lagostomus maximus : un mamífero con poliovulación y reabsorción selectiva info:eu-repo/semantics/doctoralThesis info:ar-repo/semantics/tesis doctoral info:eu-repo/semantics/acceptedVersion http://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=avaposgra&cl=CL1&d=HWA_5659 https://repositoriouba.sisbi.uba.ar/gsdl/collect/avaposgra/index/assoc/HWA_5659.dir/5659.PDF |