title: Sonographic morphology and hyaluronan content of umbilical cords of healthy and Down syndrome fetuses in early gestation.
abstract: OBJECTIVE
  To explore the sonographic vascular architecture and the hyaluronan amount and distribution of umbilical cords of healthy and trisomy 21 fetuses in early gestation.
  
  
  METHODS
  Umbilical cord sonographic morphology and morphometry of 112 consecutive normal fetuses and 11 trisomy 21 fetuses were assessed between 10 and 15 weeks of gestation. The umbilical coiling index was defined as the reciprocal of the length of one complete coil measured in a longitudinal section of the umbilical cord. The umbilical coiling angle was defined as the maximum angle between the long axis of the umbilical cord and that of the umbilical arteries. Three umbilical cord samples obtained from Down syndrome fetuses and one from a healthy fetus after voluntary termination of pregnancy at 13 weeks of gestation were used for biochemical analysis. Quantitative hyualuronan content and tissue distribution was studied using fluorophore-assisted carbohydrate electrophoresis (FACE) analysis and staining methods using biotin-labeled hyaluronan-binding protein (bHABP), respectively.
  
  
  RESULTS
  A significant correlation was present between gestational age and both the umbilical coiling index (r=-0.56, p<0.001) and the umbilical coiling angle (r=-0.43, p<0.001). The proportion of uncoiled umbilical cords was significantly higher in Down syndrome fetuses than in healthy fetuses [8/112 (7.1%) vs. 4/11 (36.4%), p<0.05]. Biochemical analysis demonstrated a higher amount and a different distribution of hyaluronan in trisomy 21 umbilical cords compared to healthy fetuses.
  
  
  CONCLUSIONS
  The umbilical cord of Down syndrome fetuses in early gestation shows peculiar sonographic vascular features and quantitative alterations of the Wharton's jelly hyaluronan.
authors.affiliation: Department of Experimental and Clinical Biomedical Science (DSBSC), University of Insubria, Varese, Italy. luigi.raio@insel.ch
authors.forename: Luigi
authors.initials: L
authors.lastname: Raio
authors.forename: Fabio
authors.initials: F
authors.lastname: Ghezzi
authors.forename: Antonella
authors.initials: A
authors.lastname: Cromi
authors.forename: Emanuele
authors.initials: E
authors.lastname: Cereda
authors.forename: Alberto
authors.initials: A
authors.lastname: Passi
mesh_terms: D000328:Adult; D001710:Biotin; D004314:Down Syndrome / Q000000981:diagnostic imaging* / Q000378:metabolism; D005260:Female; D005865:Gestational Age; D006651:Histocytochemistry; D006801:Humans; D018960:Hyaluronan Receptors; D006820:Hyaluronic Acid / Q000032:analysis*; D008423:Maternal Age; D011247:Pregnancy; D012016:Reference Values; D016216:Ultrasonography, Prenatal; D014470:Umbilical Cord / Q000737:chemistry* / Q000000981:diagnostic imaging*
chemical_list: D018960:Hyaluronan Receptors; D001710:Biotin; D006820:Hyaluronic Acid