Search results for "fetus"

Immature excitatory neurons develop during adolescence in the human amygdala.

2019

The human amygdala grows during childhood, and its abnormal development is linked to mood disorders. The primate amygdala contains a large population of immature neurons in the paralaminar nuclei (PL), suggesting protracted development and possibly neurogenesis. Here we studied human PL development from embryonic stages to adulthood. The PL develops next to the caudal ganglionic eminence, which generates inhibitory interneurons, yet most PL neurons express excitatory markers. In children, most PL cells are immature (DCX+PSA-NCAM+), and during adolescence many transition into mature (TBR1+VGLUT2+) neurons. Immature PL neurons persist into old age, yet local progenitor proliferation sharply d…

Role of oxidative stress in neonatal respiratory distress syndrome

2019

Respiratory distress syndrome is the commonest respiratory disorder in preterm infants. Although it is well known that preterm birth has a key role, the mechanisms of lung injury have not been fully elucidated. The pathogenesis of this neonatal condition is based on the rapid formation of the oxygen reactive species, which surpasses the detoxification capacity of anti-oxidative defense system. The high reactivity of free radical leads to damage to a variety of molecules and may induce respiratory cell death. There is evidence that the oxidative stress involved in the physiopathology of this disease, is particularly related to oxygen supplementation, mechanical ventilation, inflammation/infe…

Fetal neurogenesis: breathe HIF you can.

2016

Blood vessels are part of the stem cell niche in the developing cerebral cortex, but their in vivo role in controlling the expansion and differentiation of neural stem cells (NSCs) in development has not been studied. Here, we report that relief of hypoxia in the developing cerebral cortex by ingrowth of blood vessels temporo‐spatially coincided with NSC differentiation. Selective perturbation of brain angiogenesis in vessel‐specific Gpr124 null embryos, which prevented the relief from hypoxia, increased NSC expansion at the expense of differentiation. Conversely, exposure to increased oxygen levels rescued NSC differentiation in Gpr124 null embryos and increased it further in WT embryos, s…

Long-Term in vivo Evaluation of Orthotypical and Heterotypical Bioengineered Human Corneas.

2020

Purpose: Human cornea substitutes generated by tissue engineering currently require limbal stem cells for the generation of orthotypical epithelial cell cultures. We recently reported that bioengineered corneas can be fabricated in vitro from a heterotypical source obtained from Wharton’s jelly in the human umbilical cord (HWJSC). Methods: Here, we generated a partial thickness cornea model based on plastic compression nanostructured fibrin-agarose biomaterials with cornea epithelial cells on top, as an orthotypical model (HOC), or with HWJSC, as a heterotypical model (HHC), and determined their potential in vivo usefulness by implantation in an animal model. Results: No major side effects …

SARS-CoV2 vertical transmission with adverse effects on the newborn revealed through integrated immunohistochemical, electron microscopy and molecula…

2020

Background: The occurrence of trans-placental transmission of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) infection remains highly debated. Placental positivity for SARS-CoV-2 has been reported in selected cases, but infection or virus-associated disease of fetal tissues or newborns remains to be demonstrated. Methods: We screened for SARS-CoV-2 spike (S) protein expression placentas from 101 women who delivered between February 7 and May 15 2020, including 15 tested positive for SARS-CoV-2 RNA, 34 tested negative, and 52 not evaluated as they did not meet testing criteria (32), or delivered before COVID-19 pandemic declaration (20). Immunostain for SARS-CoV-2 nucleocapsid…

Extending the ALDH18A1 clinical spectrum to severe autosomal recessive fetal cutis laxa with corpus callosum agenesis

2018

IF 3.822 (2018); International audience

Mosaic-activating FGFR2 mutation in two fetuses with papillomatous pedunculated sebaceous naevus

2016

International audience; Papillomatous pedunculated sebaceous naevus (PPSN) has been described as a subtype of sebaceous naevus (SN), typically affecting the scalp and face. In contrast with Schimmelpenning syndrome, no cerebral, ocular or skeletal anomalies have hitherto been reported. We report two unrelated fetuses with PPSN, one with large pink exophytic tumours, the other with minor features but similar microscopic findings. We performed whole-exome sequencing in affected skin tissue from fetus 1, which identified a postzygotic de novo FGFR2 c.1144T>C (p.Cys382Arg) mutation in 34[middle dot]6% of reads which was absent in the parents' blood. Targeted deep sequencing of FGFR2 confirmed i…

Prenatal Air Pollution and Reduced Birth Weight: Decline in Placental Mitochondria as a Potential Mechanism.

2016

Strong epidemiological evidence links prenatal exposure to ambient air pollution and outcomes including low birth weight, intrauterine growth restriction, and preterm birth.1,2 A new study finds evidence that the association between prenatal air pollution exposure and reduced birth weight may be mediated in part by a decline in the mitochondrial content of the placenta.3 During pregnancy, the placenta supports the nourishment, growth, and development of the fetus, and mitochondria within the cells of the placenta are essential to these processes.4 Mitochondria, the cellular organelles that regulate energy production, are easily damaged by reactive oxygen species generated by oxidative stres…

2020

Aims: Current anti-hypertensive therapies cannot cure hypertension and a life-long medication is necessary. Maternal treatment may represent a promising strategy for hypertension treatment. We have previously shown that maternal treatment of spontaneously hypertensive rats (SHR) with pentaerythritol tetranitrate (PETN) leads to a persistent blood pressure reduction in the female offspring at age of 6-8 months. The underlying mechanisms include improved endothelial function resulting from long-lasting epigenetic changes. In the present study, we address the renal effects of maternal PETN treatment. Methods and Results: F0 parental SHR were fed with either normal chow or PETN-containing (1 g/…

Surge of Peripheral Arginine Vasopressin in a Rat Model of Birth Asphyxia

2018

Mammalian birth is accompanied by a period of obligatory asphyxia, which consists of hypoxia (drop in blood O2 levels) and hypercapnia (elevation of blood CO2 levels). Prolonged, complicated birth can extend the asphyxic period, leading to a pathophysiological situation, and in humans, to the diagnosis of clinical birth asphyxia, the main cause of hypoxic-ischemic encephalopathy (HIE). The neuroendocrine component of birth asphyxia, in particular the increase in circulating levels of arginine vasopressin (AVP), has been extensively studied in humans. Here we show for the first time that normal rat birth is also accompanied by an AVP surge, and that the fetal AVP surge is further enhanced in…