Thèse : Médecine : Paris : 1890. / N° d'ordre : 335.

Thesis (doctoral)--Freie Universität Berlin, 1979.

Thesis (doctoral)--Freie Universität Berlin, 1978.

Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 204-216).

Placenta growth factor (PGF) expression is downregulated in preeclampsia (PE), a leading cause of maternal morbidity and mortality. The pathophysiology of PE is thought to be manifested by a poorly perfused placenta hampered by hypoxic stress. Two stress-mediate angiogenic responses include post-transcriptional regulation of mRNA stability, and regulation of PML sequestering protein. We investigate whether these mechanisms occur in hypoxic stressed trophoblast and preeclamptic placenta. Methods: To determine transcript stability, PGF mRNA was measured in normal vs. stressed conditions, and the PGF 3'UTR was analyzed for consensus 3'AREs. To characterize stability regulation, the PGF 3'UTR was cloned into a reporter construct. To investigate the association between PGF mRNA and RNA binding proteins, an RNA-Immunoprecipitation assay was performed on trophoblast. PML study: Normal (n=6) and preeclamptic (n=6) placentae were assessed for PML expression. Immunoblot, qRT-PCR and immunohistochemistry techniques were used to determine PML gene expression and localization in placental tissue and primary cells. Results: Two consensus ARE motifs were detected within the human PGF 3'UTR at the 42nd nucleotide and the 91st nucleotide downstream from the PGF coding region. Identical and spatially conserved ARE motifs were found in bovine, rat and mouse PGF 3'UTR. Actinomycin D transcription inhibitor ii studies that were used to measure RNA decay rates in hypoxic and normal conditions, demonstrated a transcriptional response of PGF mRNA to hypoxic stress. Additionally, the PGF 3'UTR did not alter gene expression significantly relative to a site-directed mutant after 24 hours hypoxia. However, PGF 3'UTR decreased reporter activity relative to parental control, suggesting that it could function to regulate stability, but not in hypoxic stress. Western blots and immunohistochemical analyses showed the presence of three potential ARE binding proteins in trophoblast. RNA-Immunoprecipitation assays suggest that PGF mRNA may interact weakly with HuR protein. Upregulation of RNABP expression by insulin was investigated for its effects to upregulate RNABP, and was found to transcriptionally downregulate PGF mRNA. Tumor necrosis factor alpha (TNFa) treatment initiated a short-term upregulation of PGF mRNA. PML Study Results: PML protein was immunolocalized within nuclei of villus mesenchyme, but largely absent in trophoblast nuclei. A trend for increased PML reactivity in placenta of preeclamptic patients was observed. Immunoblot analyses of nuclear extracts confirmed relative increases (~3 fold) of PML expression in preeclamptic placentae (p< 0.05). Conversely, less PML mRNA (~2 fold) was detected in preeclamptic versus normal placental samples. In vitro, PML expression could be increased by hypoxia in cultured endothelial cells but not trophoblast. Conclusion: These results suggest that a post-transcriptional mechanism directed through the 3'UTR does not regulate PGF mRNA expression in stressed trophoblast. PML Study conclusion: Increased PML protein expression in preeclamptic villi suggests it could contribute to decreased vascularity and placental growth and/or function.

archives@tulane.edu / Preeclampsia is a leading cause of maternal and fetal mortality, affecting up to 8% of pregnancies. Clinically, preeclampsia is diagnosed by the new onset of maternal hypertension and proteinuria presenting in the second half of gestation. The etiology of this disease, however, occurs during early development with abnormal vascular remodeling that results in reduced placental perfusion and hypoxia. This abnormal placental function increases the production of soluble antiangiogenic factors which are then released into maternal circulation, creating the systemic endothelial dysfunction associated with maternal symptoms. Despite being a critical indicator of disease progression and therapeutic response, placental function cannot be fully characterized by existing imaging modalities. The objective of this work was to develop multimodal imaging and image processing tools characterize placental function in the reduced uterine perfusion pressure (RUPP) rat model of preeclampsia. We demonstrate spectral photoacoustic (sPA) imaging and contrast-enhanced ultrasound (CEUS) imaging of the longitudinal changes in placental oxygenation, perfusion, and vascular growth in the development of preeclampsia and evaluate the placental response to therapeutic intervention. / 1 / Dylan J Lawrence

La presencia de óbito fetal es una indicación absoluta de examen de la placenta, la histopatología de la placenta puede brindar información importante para explicar el deceso, el objetivo de este estudio es reportar la prevalencia de hallazgos histopatológicos de la placenta proveniente de óbitos fetales. Metodología. Estudio caso control. Casos :114 placentas, controles :114 . Resultados: El 86 % de las placentas procedentes de óbitos fetales presentan lesiones inflamatorias del lado materno, el estadio intermedio o corioamnionitis aguda y el grado severo son los más frecuentes (49,1 % y 52,63 % respectivamente). El 22,8 % de las placentas presentó lesiones inflamatorias fetales siendo la vasculitis coriónica o flebitis umbilical la más frecuente (12,8 %) y funisitis necrotizante (6,14%). Las lesiones no inflamatorias son Deposito de fibrina (60,5% p=0,0005), infarto(43,9%), calcificaciones(31,6%), fibrosis intravellositaria (25,4%), corangiosis (13,2 %) , espacio intervelloso amplio (13,2%). El porcentaje de autopsias en óbitos fetales del tercer trimestre es del 10,52 %.

No description available.

No description available.

Objetivo: Identificar los factores de riesgo de las gestantes con diagnóstico de placenta previa. Metodología: estudio descriptivo, retrospectivo y transversal realizado en el Hospital Nacional Edgardo Rebagliati Martins en el periodo enero-setiembre 2015, en el Departamento de Obstetricia, siendo la población y muestra 46 casos comprobado por ecografía en el segundo y/o tercer trimestre de gestación. Resultados: el grupo etario más afectado fueron las mujeres añosas con 54,3%, el 63% fueron multíparas, el 71,7% tuvo al menos una cirugía uterina previa. El legrado uterino fue la cirugía más frecuente con 28,3%, seguido de la combinación cesárea mas legrado uterino con 21,7% y en tercer lugar la cesárea con 19,6%. El tipo de placenta previa más frecuente fue el total o completo con 71,7%. Conclusión: la mayoría de pacientes estudiadas presentaban por lo menos un factor de riesgo relacionado a placenta previa, por lo que se tiene que descartar y o diagnosticar esta entidad de la manera más oportuna y planear el manejo respectivo, disminuyendo la morbimortalidad materno perinatal.