Postpartum Problems (The Puerperium), Including Neonatal Problems – Questions
Rekha Wuntakal, Madhavi Kalidindi, Tony Hollingworth in Get Through, 2014
With respect to the fetal circulation, which one of the following is true? Umbilical cord contains two veins and one artery.Umbilical vein carries oxygenated blood from the fetus.Umbilical artery carries deoxygenated blood from the fetus.Umbilical vein carries deoxygenated blood to the fetus.Umbilical artery carries oxygenated blood to the fetus.
Physical and functional growth and development
Nick Draper, Helen Marshall in Exercise Physiology, 2014
During fetal life, a miniature cardiovascular system is fully developed by 11 weeks of gestation. The arrangement of the circulatory system is such that the two sides of the heart work in parallel (in contrast to the series arrangement in the adult) and three shunts are present which allow blood to bypass organs with little or no function. For example, only about 10–15% of the fetal circulation passes through the lungs. Fetal lungs are unsuitable for gas exchange as they are filled with amniotic fluid and blood constituents. Despite this, the respiratory centres of the brain and appropriate neuromuscular mechanisms allow for respiratory movements in fetal lungs. The site of fetal gas exchange is the placenta which connects the maternal and fetal circulations via the umbilical vein and arteries. The umbilical vein carries oxygen and nutrients from the mother’s circulation to the fetus, whereas the umbilical arteries transport venous blood from the fetus to the placenta for reoxygenation and for the removal of waste products into the maternal circulation.
Introduction to the clinical stations
Sukhpreet Singh Dubb in Core Surgical Training Interviews, 2020
Paediatric umbilical hernias typically close by the age of 4–5 without intervention; however, although complications are rare they must be recognised and acted on immediately. The umbilicus transmits the contents of the umbilical cord via a defect in the linea alba. The umbilical ring usually closes by contraction, the umbilical vein fibroses to become the round ligament of the liver, and attaches to the umbilicus. This provides anchorage to the umbilicus and protects against the formation of a hernia, however, a minority of patients are susceptible to hernia formation if this process does not occur correctly. Important risk factors for umbilical hernia formation include: Low birth weightAfrican ancestryTrisomy 13, 18 and 21Congenital hypothyroidismHurler's syndromeBeckwith-Wiedemann syndrome
Prenatal diagnosis of the persistent right umbilical vein, incidence and clinical significance
Published in Journal of Obstetrics and Gynaecology, 2022
Gulsah Dagdeviren, Ayse Keles, Ozge Yücel Celik, Aykan Yucel, Dilek Sahin
In normal embryonic development, obliteration of the right umbilical vein begins at 4 weeks gestation and at 7 weeks it disappears. The left umbilical vein connects to the left portal vein of the foetal liver and carries all blood from the placenta to the foetus (Yagel et al. 2010a, 2010b). The persistent right umbilical vein (PRUV) is a pathological vascular anomaly occurring in embryonic development, in which the left umbilical vein regresses and the right umbilical vein remains open. The prevalence of intrahepatic PRUV has been reported to be 0.13% (Lide et al. 2016). The cause of PRUV is unknown. Thrombus, teratogens or folic acid deficiency is possible aetiologies (Weichert et al. 2011). PRUV can occur in an isolated form that represents its normal variant or be associated with other major or minor anomalies. The prognosis of isolated PRUV cases is good, but the prognosis of cases associated with DV agenesis is poor (Martinez et al. 2013).
TRAP Sequence in Monochorionic/Monoamniotic (MC/MA) Discordant Twins: Two Cases Treated with Fetoscopic Laser Surgery
Published in Fetal and Pediatric Pathology, 2018
Gabriele Tonni, Gianpaolo Grisolia, Paolo Zampriolo, Federico Prefumo, Anna Fichera, Paola Bonasoni, Mathilde Lefebvre, Suonavy Khung-Savatovsky, Fabien Guimiot, Jonathan Rosenblatt, Edward Araujo Júnior
In the placenta, the TRAP sequence is characterized by superficial vascular connections that exclude the deep villous placental circulation to the acardiac twin. These vascular anastomoses are among chorionic vessels and consist of wide artery–artery (A–A) and vein–vein (V–V) connections. In this kind of vascular organization, the normally formed co-twin, known as the pump twin, directly perfuses the acardiac twin through the umbilical artery (A–A connection) with subsequent reversed circulation. In normal condition, oxygenated blood from the placenta perfuses the fetus through the umbilical vein and then goes via the ductus venosus to the right atrium. In TRAP sequence, the blood from the artery of the pump twin perfuses directly the acardiac twin at the level of the internal iliac arteries. It is a mixture of blood that comes from oxygenated blood from the aortic arch and the desaturated blood from the fetal venous system (from the ductus arteriosus). Except from the head and the upper limbs that recieve highly oxygenated blood thanks to the right-left shunt of the foramen ovale, this mixed blood is adequately oxygenated for the rest of the body of the normal twin [31–33]. However, the pump twin may also have complications from this abnormal circulation, especially high-output cardiac failure leading to fetal hydrops. Moreover, the pump twin receives decreased oxygenated blood due to mixing of the deoxygenated umbilical vein blood from the reversed circulation of the acardiac twin. In fact, the mortality rate for the pump twin is high as 50%, which also involves the consequences of therapeutic treatments [34].
Fabrication of a co-culture micro-bioreactor device for efficient hepatic differentiation of human induced pluripotent stem cells (hiPSCs)
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Mousa Kehtari, Bahman Zeynali, Masoud Soleimani, Mahboubeh Kabiri, Ehsan Seyedjafari
The third advantage of our micro-bioreactor device is that unlike other previous designs, it allows co-culture of other cells beside iPSCs-Heps. In the present study, HUVECs were chosen as a well-established and standardized cell source for parenchymal–endothelial cell co-culture. As the umbilical vein is the major afferent vessel in the fetal liver [1,30], HUVECs might thereby be crucial for early liver development. For this reason, in several studies HUVECs we successfully utilized as supporting cells for hepatic differentiation [31–33]. Takebe et al. [31] have shown that iPSCs-derived hepatocytes co-cultured with HUVECs and MSCs, self-organized into liver organoids, thus providing suitable environment that enhance the differentiation of hepatocyte-like cells. Asai et al. [34] established a liver organoid using iPSCs, MSCs and HUVECs, and showed that released soluble factors from MSCs and HUVECs induced a hepatocyte-like phenotype in iPSCs and promoted hepatocyte maturation in liver organoids. Our findings also showed that co-cultivation of iPSCs with HUVECs in our micro-bioreactor device can improve differentiation and maturation of iPSCs to hepatocyte-like cells, confirming the importance of endothelial cells during hepatocyte differentiation and maturation.
Related Knowledge Centers
- Ductus Venosus
- Fetus
- Inferior Vena Cava
- Placenta
- Vein
- Atrium
- Blood
- Prenatal Development
- Chorionic Villi
- Portal Vein