L'institutionnalisation de l'enfance déviante : le cas de l'Hospice Saint-Charles (1870-1950)

La présente recherche se penche sur les aspects sociétaux de l'institutionnalisation de l'enfance déviante dans une société rurale en voie d'industrialisation. En Occident, la construction de l'enfance, modelée selon les contextes politiques et sociaux, influence et s'incarne dans l'évolution des lois sur la prise en charge de l'enfance au Québec. Dans la province, les lois de 1869, instaurant le réseau des écoles de réforme et d'industrie, marquent les premiers pas étatiques dans le champ de l'institutionnalisation de l'enfance déviante, c'est-à-dire l'enfance délinquante et l'enfance en danger. Cependant, plusieurs auteurs remarquent un écart entre ces lois et la vie à l'intérieur des institutions qu'elles créent. Le cas de l'Hospice St-Charles de Québec permettra d'illustrer ce décalage en démontrant comment les Soeurs du Bon-Pasteur remplissent leur mission. De plus, l'étude des jeunes ayant fréquenté l'Hospice permettra de dresser un portrait global et familial des enfants touchés par les lois de 1869

Melatonin: the watchdog of villous trophoblast homeostasis against hypoxia/reoxygenation-induced oxidative stress and apoptosis.

International audienceHuman placenta produces melatonin and expresses its receptors. We propose that melatonin, an antioxidant, protects the human placenta against hypoxia/reoxygenation (H/R)-induced damage. Primary term villous cytotrophoblasts were cultured under normoxia (8% O2) with or without 1mM melatonin for 72h to induce differentiation into the syncytiotrophoblast. The cells were then cultured for an additional 22h under normoxia or subjected to hypoxia (0.5% O2) for 4h followed by 18h reoxygenation (8% O2) with or without melatonin. H/R induced oxidative stress, which activated the Bax/Bcl-2 mitochondrial apoptosis pathway and the downstream fragmentation of DNA. Villous trophoblast treatment with melatonin reversed all the negative effects induced by H/R to normoxic levels. This study shows that melatonin protects the villous trophoblast against H/R-induced oxidative stress and apoptosis and suggests a potential preventive and therapeutic use of this indolamine in pregnancy complications characterized by syncytiotrophoblast survival alteration

Quantitative PCR pitfalls: the case of the human placenta.

International audienceReverse-transcription quantitative polymerase chain reaction (RT-qPCR) is a rapid and high throughput gene expression quantification technology. In order to obtain accurate results, several key experimental design and standardization steps must be rigorously followed as previously described in the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines. This study investigates the effect of reference gene normalization and the impact of RNA degradation on gene expression of 8-oxoguanine DNA glycosylase in human placenta from pregnancies complicated by preeclampsia and gestational diabetes mellitus and their gestation-matched controls. The data presented here show how RNA quality and appropriate reference gene selection is not only important to obtain accurate and reproducible RT-qPCR data but how different and even opposite results can be reported if the key steps outlined in the MIQE guidelines are not followed. The procedures and associated results presented in this study provide the first practical application of the MIQE guidelines to placental analysis in normal and pathological pregnancies

Erratum to: Quantitative PCR Pitfalls: The Case of the Human Placenta.

International audienc

Novel role of the renin-angiotensin system in preeclampsia superimposed on chronic hypertension and the effects of exercise in a mouse model.

International audienceGestational hypertensive disorders, such as preeclampsia, affect 6% to 8% of all pregnancies in North America, and they are the leading cause of maternal mortality in industrialized countries, accounting for 16% of deaths. Women with hypertension have an increased risk (15% to 25%) of developing preeclampsia. Our aim was to investigate the mechanisms implicated in preeclampsia superimposed on chronic hypertension and in the protective effects of exercise in a mouse model. Female mice overexpressing human angiotensinogen and human renin were used as a model of preeclampsia superimposed on chronic hypertension. In the trained group, mothers were placed in cages with access to a wheel before mating, and they remained within these throughout gestation. Blood pressure was measured by telemetry. We found that angiotensin II type I receptor was increased, whereas the Mas receptor was decreased in the placenta and the aorta of pregnant sedentary transgenic mice. This would produce a decrease in angiotensin-(1-7) effects in favor of angiotensin II. Supporting the functional contribution of this modulation, we found that the prevention of most pathological features in trained transgenic mice was associated with a normalization of placental angiotensin II type 1 and Mas receptors and an increase in aortic Mas receptor. We also found reduced circulating and placental soluble Fms-like tyrosine kinase-1 in trained transgenic mice compared with sedentary mice. This study demonstrates that modulation of the renin-angiotensin system is a key mechanism in the development of preeclampsia superimposed on chronic hypertension, which can be altered by exercise training to prevent disease features in an animal model