17 research outputs found

    Effect of maternal administration of betamethasone on peripheral arterial development in fetal rabbit lungs

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    Objectives: Glucocorticoids promote lung maturation and reduce the incidence of respiratory distress syndrome in premature newborns. We hypothesized that betamethasone (BM), which is known to induce thinning of the alveolar walls, would also thin the arterial media and adventitia of intra-parenchymatic vessels in developing rabbit lungs. Study Design: 112 fetuses from 21 time-mated, pregnant, giant white rabbits received maternal injections of BM at either 0.05 or 0.1 mg/kg/day on days 25-26 of gestational age. Controls received either saline (10 does, 56 fetuses) or no injection (10 does, 59 fetuses). Fetuses were harvested from day 27 onwards until term (day 31). 44 additional fetuses (8 does) were harvested between days 23 and 26. Endpoints were wet lung-to-body weight ratio, vascular morphometric indices and immunohistochemistry staining for α-smooth muscle actin, Flk-1, vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS). ANOVA (Tukey's test) and independent t test (p < 0.05) were used for comparison between BM and saline groups. Results: Maternal BM injected on days 25-26 to pregnant rabbits induced a significant decrease in fetal body and lung weight and the lung-to-body weight ratio in the preterm pups shortly after injection. BM led to a dose-dependent thinning of the arterial media and adventitia (pulmonary arteries with an external diameter (ED) of <100 μm), to an increase in the percentage of non-muscularized peripheral vessels (ED <60 μm), in eNOS and VEGF immunoreactivity of the endothelial and smooth muscle cells in the pulmonary vessels and to an increase in Flk-1-positive pulmonary epithelial cell density. Conclusions: Maternal administration of BM caused thinning of the arterial wall of pulmonary vessels (ED <100 μm) and a decrease in muscularization in peripheral vessels (ED <60 μm). This coincided with increased expression of Flk-1 in the endothelium and smooth muscle cells of the pulmonary arteries. All the effects studied were dose-dependent. Copyrigh

    Agroforesterie et services écosystémiques en zone tropicale

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    Respectueux de l’environnement et garantissant une sécurité alimentaire soutenue par la diversification des productions et des revenus qu’ils procurent, les systèmes agroforestiers apparaissent comme un modèle prometteur d’agriculture durable dans les pays du Sud les plus vulnérables aux changements globaux. Cependant, ces systèmes agroforestiers ne peuvent être optimisés qu’à condition de mieux comprendre et de mieux maîtriser les facteurs de leurs productions. L’ouvrage présente un ensemble de connaissances récentes sur les mécanismes biophysiques et socio-économiques qui sous-tendent le fonctionnement et la dynamique des systèmes agroforestiers. Il concerne, d’une part les systèmes agroforestiers à base de cultures pérennes, telles que cacaoyers et caféiers, de régions tropicales humides en Amérique du Sud, en Afrique de l’Est et du Centre, d’autre part les parcs arborés et arbustifs à base de cultures vivrières, principalement de céréales, de la région semi-aride subsaharienne d’Afrique de l’Ouest. Il synthétise les dernières avancées acquises grâce à plusieurs projets associant le Cirad, l’IRD et leurs partenaires du Sud qui ont été conduits entre 2012 et 2016 dans ces régions. L’ensemble de ces projets s’articulent autour des dynamiques des systèmes agroforestiers et des compromis entre les services de production et les autres services socio-écosystémiques que ces systèmes fournissent

    Les hydrothorax foetaux de diagnostic anténatal (étude rétrospective de 1993 à 2007)

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    LILLE2-BU Santé-Recherche (593502101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

    Diagnostic des cardiopathies foetales au CHRU de Lille entre 1999 et 2001 (Ă  propos de 351 observations)

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    LILLE2-BU Santé-Recherche (593502101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

    Bilan d'activité et évaluation du centre pluridisciplinaire de diagnostic prénatal de l'hôpital Jeanne de Flandre en 1999

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    LILLE2-BU Santé-Recherche (593502101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

    DĂ©pistage de la trisomie 21 (information, consentement et satisfaction des patientes)

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    LILLE2-BU Santé-Recherche (593502101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

    Antenatal Assessment of the Prognosis of Congenital Diaphragmatic Hernia: Ethical Considerations and Impact for the Management

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    Congenital diaphragmatic hernia (CDH) is associated with abnormal pulmonary development, which is responsible for pulmonary hypoplasia with structural and functional abnormalities in pulmonary circulation, leading to the failure of the cardiorespiratory adaptation at birth. Despite improvement in treatment options and advances in neonatal care, mortality remains high, at close to 15 to 30%. Several risk factors of mortality and morbidities have been validated in fetuses with CDH. Antenatal assessment of lung volume is a reliable way to predict the severity of CDH. The two most commonly used measurements are the observed/expected lung to head ratio (LHRo/e) and the total pulmonary volume (TPV) on MRI. The estimation of total pulmonary volume (TPVo/e) by means of prenatal MRI remains the gold standard. In addition to LHR and TPV measurements, the position of the liver (up, in the thorax or down, in the abdomen) also plays a role in the prognostic evaluation. This prenatal prognostic evaluation can be used to select fetuses for antenatal surgery, consisting of fetoscopic endoluminal tracheal occlusion (FETO). The antenatal criteria of severe CDH with an ascended liver (LHRo/e or TPVo/e &lt; 25%) are undoubtedly associated with a high risk of death or significant morbidity. However, despite the possibility of estimating the risk in antenatal care, it is difficult to determine what is in the child&rsquo;s best interest, as there still are many uncertainties: (1) uncertainty about individual short-term prognosis; (2) uncertainty about long-term prognosis; and (3) uncertainty about the subsequent quality of life, especially when it is known that, with a similar degree of disability, a child&rsquo;s quality of life varies from poor to good depending on multiple factors, including family support. Nevertheless, as the LHR decreases, the foreseeable &ldquo;burden&rdquo; becomes increasingly significant, and the expected benefit is increasingly unlikely. The legal and moral principle of the proportionality of medical procedures, as well as the prohibition of &ldquo;unreasonable obstinacy&rdquo; in all investigations or treatments undertaken, is necessary in these situations. However, the scientific and rational basis for assessing the long-term individual prognosis is limited to statistical data that do not adequately reflect individual risk. The risk of self-fulfilling prophecies should be kept in mind. The information given to parents must take this uncertainty into account when deciding on the treatment plan after birth
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