Umbilical vessel catheter retro-exchange technique (U-RET) for repeat use of the umbilical artery for neonatal vascular intervention: Technical note

A high flow arteriovenous shunts in newborns may require urgent endovascular treatment right immediately after delivery if high output cardiac failure is resistant to medical treatment. The umbilical approach is often the first choice of the access route for endovascular treatment in the newborn. It is, however, not infrequent that the patient has an extensive lesion, which necessitates a second session of treatment because of the limitation of the usable amount of the contrast material in one session. In such a case, re-puncturing the femoral artery is difficult and carries the risk of leg ischemia. On the other hand, leaving the umbilical sheath for the second procedure carries risks of infection, thrombosis, and vessel injury. Herein we introduce our umbilical vessel catheter (UVC) retro-exchange technique (U-RET) in which we replace the umbilical sheath to a 3.5Fr UVC at the end of the first endovascular procedure to preserve the umbilical artery access and prepare for the repeated use. We believe that this method minimizes the risks of infection and vessel injury.

Female Bioengineering: Primordial Germ Cell Differentiation of Mesenchymal Stem Cells onto Placental Scaffolds

Introduction: Female infertility is a condition that is currently treated through the maximization of existing reserves; a necessity due to the fact that a true reversal of the processes leading to infertility is not yet technologically possible. This experiment examined the ability of mesenchymal stem cells to differentiate into primordial germ cells (PGC) when cultured onto the placental scaffold. Methods: To produce the scaffolds, the cotelydons were collected and decellularized by umbilical vessel SDS perfusion. Adipose derived cells were isolated based on rapid adherence to the plastic. Results: The isolated cells displayed the markers CD90 and 105, while lacked CD34 and CD45. When seeded onto the scaffold, the cells successfully differentiated into PGC like cells, displaying typical PGCs markers, including STELLA, OCT4, DAZL and VASA. Discussion: These materials were chosen for their low cost and wide availability. The data in this study show the promising potential of cell-scaffold complex to support the development of female tissue engineering-based regenerative medicine therapies.

Heterotopic Liver Nodule Compressing a Two-Vessel Umbilical Cord: An Unusual Cause of Intrauterine Fetal Demise

Heterotopic liver tissue in the umbilical cord is rare, and the outcome is quite unpredictable based on the few reported cases. We present a case of heterotopic liver nodule in the umbilical cord of a midtrimester fetus who died in utero. Although such association has only been reported once, heterotopic nodular tissue in the umbilical cord must be regarded as a potential cause of fetal demise by a mechanism analogous to the more common umbilical cord abnormalities resulting in umbilical vessel compromise.

Furcate insertion of the umbilical cord: pathological and clinical characteristics in 132 cases

ObjectivesFurcate cord insertion is a rare abnormality affecting approximately 0.1% of all pregnancies. Macroscopically, the umbilical vessels separate before reaching the placenta, lose their Wharton’s jelly, and insert at the placenta centrally, eccentrically, or marginally. The aim of this retrospective study was to determine the prevalence of furcate cord insertion more accurately, the pathological characteristics, and clinical outcomes.MethodsWe conducted a retrospective study of 132 cases of furcate insertion of the umbilical cord using the pathological database of the Charité University Hospital Berlin, Germany, between 1993 and 2016. This included 99 cases, including one termination of pregnancy within our institution and 33 cases from external hospitals. An analysis of the pathological features of the 132 cases and the perinatal outcome of the 98 cases within our institution were performed.ResultsFurcate cord insertion occurred in 0.16% pregnancies. Of the 132 cases, seven cases of intrauterine fetal deaths were observed. Three of those could be linked to the furcate cord insertion. In two of those cases, single umbilical vessel rupture was identified as the cause of fetal death.ConclusionsIn most cases of furcate cord insertion, the outcome is good; however, intrauterine fetal death occurs in approximately 1.02% of cases.

Vascular dimorphism ensured by regulated proteoglycan dynamics favors rapid umbilical artery closure at birth

The umbilical artery lumen closes rapidly at birth, preventing neonatal blood loss, whereas the umbilical vein remains patent longer. Here, analysis of umbilical cords from humans and other mammals identified differential arterial-venous proteoglycan dynamics as a determinant of these contrasting vascular responses. The umbilical artery, but not the vein, has an inner layer enriched in the hydrated proteoglycan aggrecan, external to which lie contraction-primed smooth muscle cells (SMC). At birth, SMC contraction drives inner layer buckling and centripetal displacement to occlude the arterial lumen, a mechanism revealed by biomechanical observations and confirmed by computational analyses. This vascular dimorphism arises from spatially regulated proteoglycan expression and breakdown. Mice lacking aggrecan or the metalloprotease ADAMTS1, which degrades proteoglycans, demonstrate their opposing roles in umbilical vascular dimorphism, including effects on SMC differentiation. Umbilical vessel dimorphism is conserved in mammals, suggesting that differential proteoglycan dynamics and inner layer buckling were positively selected during evolution.

Vascular dimorphism ensured by regulated proteoglycan dynamics favors rapid umbilical artery closure at birth

The umbilical artery lumen occludes rapidly at birth, preventing blood loss, whereas the umbilical vein remains patent, providing the newborn with a placental infusion. Here, we identify differential arterial-venous proteoglycan dynamics as a determinant of these contrasting vascular responses. We show that the umbilical artery, unlike the vein, has an inner layer enriched in the hydrated proteoglycan aggrecan, external to which lie contraction-primed smooth muscle cells (SMC). At birth, SMC contraction drives inner layer buckling and centripetal displacement to occlude the arterial lumen, a mechanism elicited by biomechanical and computational analysis. Vascular dimorphism arises from spatially regulated proteoglycan expression and breakdown in umbilical vessels. Mice lacking aggrecan or the metalloprotease ADAMTS1, which degrades proteoglycans, demonstrated their opposing roles in umbilical cord arterial-venous dimorphism and contrasting effects on SMC differentiation. Umbilical vessel dimorphism is conserved in mammals, suggesting that their differential proteoglycan dynamics were a positive selection step in mammalian evolution.

Recapitulation of Trophoblast Invasion During Pregnancy in a Physiological Hypoxia Induced Microfluidic Device

Trophoblast invasion and remodeling of uterine spiral artery is closely related to the healthy pregnancy and normal development of fetus. However, if the trophoblast invasion is inhibited and the spiral artery remodeling process is not sufficiently done, this promotes grave pregnancy diseases such as pre-eclampsia. In this research we focused on one of the major factors that affect trophoblast invasion, oxygen concentration. We designed a microfluidic device fabricated with Polydimethylsiloxane (PDMS) which can mimic the microenvironment of the placenta and control physiological oxygen concentration. Human umbilical vessel cells (HUVEC) and trophoblasts (HTR-8) were cultured inside the microfluidic device to recapitulate the placental microenvironment. HUVECs and trophoblasts were co-cultured under normoxic and hypoxic condition to recapitulated trophoblast invasion. We anticipate this device to be utilized as a research model for improve our understandings on mechanisms of trophoblast invasion and a possible platform for developing treatment methods and medicines for pregnancy disorders.