69 research outputs found
What neonatal complications should the pediatrician be aware of in case of maternal gestational diabetes?
In the epidemiologic context of maternal obesity and type 2 diabetes (T2D), the incidence of gestational diabetes has significantly increased in the last decades. Infants of diabetic mothers are prone to various neonatal adverse outcomes, including metabolic and hematologic disorders, respiratory distress, cardiac disorders and neurologic impairment due to perinatal asphyxia and birth traumas, among others. Macrosomia is the most constant consequence of diabetes and its severity is mainly influenced by maternal blood glucose level. Neonatal hypoglycemia is the main metabolic disorder that should be prevented as soon as possible after birth. The severity of macrosomia and the maternal health condition have a strong impact on the frequency and the severity of adverse neonatal outcomes. Pregestational T2D and maternal obesity significantly increase the risk of perinatal death and birth defects. The high incidence of maternal hyperglycemia in developing countries, associated with the scarcity of maternal and neonatal care, seriously increase the burden of neonatal complications in these countries
Pneumopathie congénitale à cytomégalovirus chez un nouveau-né à terme né de mère séropositive pour le VIH
International audienceBackground: Cytomegalovirus (CMV) is one of the most common intrauterine infections, affecting approximately 1% of all live births. There are few reports on congenital CMV infections manifesting as isolated pneumonitis.Case report: We report a case of congenital CMV with neonatal respiratory distress affecting an HIV-exposed uninfected infant. This infant required noninvasive ventilation beginning within the first 15min of life. The initial chest X-ray showed diffuse bilateral ground-glass opacifications. Bacterial infection, meconium aspiration and hyaline membrane disease were excluded. Salivary quantitative CMV PCR was positive (2,342,261IU/mL) and serum viral load for CMV was low (476IU/mL). Bronchoalveolar lavage (BAL) performed on day 12 for quantitative CMV PCR was significantly positive (1,045,942IU/mL). Intravenous ganciclovir treatment was started on day 14 (7.5mg/kg/12h) for 2 weeks and oral valganciclovir (15mg/kg/12h) was given for 4 weeks afterwards. Ventilatory support was stopped on day 18. HIV serum viral load was negative on day 30.Discussion: Congenital CMV infection can present as isolated pneumonitis with persistent neonatal respiratory symptoms, emphysematous lung disease, or persistent pulmonary hypertension. If this diagnosis is suspected, and even if CMV viremia remains low, BAL with quantitative CMV PCR must be performed to ascertain the diagnosis and indicate antiviral treatment. HIV-exposed uninfected infants have higher rates of congenital CMV infection when the mother's CD4 rate is<200/mm3. Most cases of CMV transmission in HIV-exposed uninfected infants have occurred by maternal endogenous reactivation or reinfection
The offspring of the diabetic mother--short- and long-term implications.
In the 1980s, David Barker and Colleagues proposed that the major causes of cardiovascular and metabolic diseases have their roots in early development. There is now robust evidence that an hyperglycemic intrauterine environment is responsible not only for significant short-term morbidity in the fetus and the neonate but also for an increased risk of developing diabetes as well as other chronic, noncommunicable diseases at adulthood. The risk is higher in pregestational diabetes, but unrecognized and/or poorly managed gestational diabetes (GDM) may have similar consequences. Although a relatively clear picture of the pathogenesis of the fetal and neonatal complications of maternal diabetes and of their interrelationship is available today, the intimate molecular mechanisms involved in the long term are far from being understood. While the rate of GDM is sharply increasing in association with the pandemic of obesity and of type 2 diabetes over the world, we review here the current understanding of short- and long-term outcomes of fetuses exposed to a diabetic environment
Stress oxydant chez l'enfant prématuré : causes, biomarqueurs et possibilités thérapeutiques [Oxidative stress after preterm birth: Origins, biomarkers, and possible therapeutic approaches].
The survival of preterm babies has increased over the last few decades. However, disorders associated with preterm birth, known as oxygen radical diseases of neonatology, such as retinopathy, bronchopulmonary dysplasia, periventricular leukomalacia, and necrotizing enterocolitis are severe complications related to oxidative stress, which can be defined by an imbalance between oxidative reactive species production and antioxidant defenses. Oxidative stress causes lipid, protein, and DNA damage. Preterm infants have decreased antioxidant defenses in response to oxidative challenges, because the physiologic increase of antioxidant capacity occurs at the end of gestation in preparation for the transition to extrauterine life. Therefore, preterm infants are more sensitive to neonatal oxidative stress, notably when supplemental oxygen is being delivered. Furthermore, despite recent advances in the management of neonatal respiratory distress syndrome, controversies persist concerning the oxygenation saturation targets that should be used in caring for preterm babies. Identification of adequate biomarkers of oxidative stress in preterm infants such as 8-iso-prostaglandin F2α, and adduction of malondialdehyde to hemoglobin is important to promote specific therapeutic approaches. At present, no therapeutic strategy has been validated as prevention or treatment against oxidative stress. Breastfeeding should be considered as the main measure to improve the antioxidant status of preterm infants. In the last few years, melatonin has emerged as a protective molecule against oxidative stress, with antioxidant and free-radical scavenger roles, in experimental and preliminary human studies, giving hope that it can be used in preterm infants in the near future
Maintenance of methylation profile in imprinting control regions in human induced pluripotent stem cells
International audienceBackground: Parental imprinting is an epigenetic mechanism that leads to monoallelic expression of a subset of genes depending on their parental origin. Imprinting disorders (IDs), caused by disturbances of imprinted genes, are a set of rare congenital diseases that mainly affect growth, metabolism and development. To date, there is no accurate model to study the physiopathology of IDs or test therapeutic strategies. Human induced pluripotent stem cells (iPSCs) are a promising cellular approach to model human diseases and complex genetic disorders. However, aberrant hypermethylation of imprinting control regions (ICRs) may appear during the reprogramming process and subsequent culture of iPSCs. Therefore, we tested various conditions of reprogramming and culture of iPSCs and performed an extensive analysis of methylation marks at the ICRs to develop a cellular model that can be used to study IDs. Results: We assessed the methylation levels at seven imprinted loci in iPSCs before differentiation, at various passages of cell culture, and during chondrogenic differentiation. Abnormal methylation levels were found, with hypermethylation at 11p15 H19/IGF2:IG-DMR and 14q32 MEG3/DLK1:IG-DMR, independently of the reprogramming method and cells of origin. Hypermethylation at these two loci led to the loss of parental imprinting (LOI), with biallelic expression of the imprinted genes IGF2 and DLK1, respectively. The epiPS ™ culture medium combined with culturing of the cells under hypoxic conditions prevented hypermethylation at H19/IGF2:IG-DMR (ICR1) and MEG3/DLK1:IG-DMR, as well as at other imprinted loci, while preserving the proliferation and pluripotency qualities of these iPSCs. Conclusions: An extensive and quantitative analysis of methylation levels of ICRs in iPSCs showed hypermethylation of certain ICRs in human iPSCs, especially paternally methylated ICRs, and subsequent LOI of certain imprinted genes. The epiPS ™ culture medium and culturing of the cells under hypoxic conditions prevented hypermethylation of ICRs in iPSCs. We demonstrated that the reprogramming and culture in epiPS ™ medium allow the generation of control iPSCs lines with a balanced methylation and ID patient iPSCs lines with unbalanced methylation. Human iPSCs are therefore a promising cellular model to study the physiopathology of IDs and test therapies in tissues of interest
Endothelial dysfunction in individuals born after fetal growth restriction: cardiovascular and renal consequences and preventive approaches.
Individuals born after intrauterine growth restriction (IUGR) have an increased risk of perinatal morbidity/mortality, and those who survive face long-term consequences such as cardiovascular-related diseases, including systemic hypertension, atherosclerosis, coronary heart disease and chronic kidney disease. In addition to the demonstrated long-term effects of decreased nephron endowment and hyperactivity of the hypothalamic-pituitary-adrenal axis, individuals born after IUGR also exhibit early alterations in vascular structure and function, which have been identified as key factors of the development of cardiovascular-related diseases. The endothelium plays a major role in maintaining vascular function and homeostasis. Therefore, it is not surprising that impaired endothelial function can lead to the long-term development of vascular-related diseases. Endothelial dysfunction, particularly impaired endothelium-dependent vasodilation and vascular remodeling, involves decreased nitric oxide (NO) bioavailability, impaired endothelial NO synthase functionality, increased oxidative stress, endothelial progenitor cells dysfunction and accelerated vascular senescence. Preventive approaches such as breastfeeding, supplementation with folate, vitamins, antioxidants, L-citrulline, L-arginine and treatment with NO modulators represent promising strategies for improving endothelial function, mitigating long-term outcomes and possibly preventing IUGR of vascular origin. Moreover, the identification of early biomarkers of endothelial dysfunction, especially epigenetic biomarkers, could allow early screening and follow-up of individuals at risk of developing cardiovascular and renal diseases, thus contributing to the development of preventive and therapeutic strategies to avert the long-term effects of endothelial dysfunction in infants born after IUGR
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