Reverse end-diastolic flow in a fetus with a rare liver malformation: a case report

<p>Abstract</p> <p>Introduction</p> <p>We describe a case of early and persistent reverse end-diastolic flow in the middle cerebral artery in a fetus with severe ascites. These features are associated with a rare liver malformation known as ductal plate malformation.</p> <p>Case presentation</p> <p>A 28-year-old Caucasian woman was referred to our high-risk obstetric unit at 24 weeks' gestation for fetal ascites detected during a routine ultrasound examination. During her hospitalization we performed medical investigations, including a fetal paracentesis, to detect the etiology of fetal ascites. The cause of fetal ascites (then considered non-immune or idiopathic) was not evident, but a subsequent ultrasound examination at 27 weeks' gestation showed a reverse end-diastolic flow in the middle cerebral artery without any other Doppler abnormalities. A cesarean section was performed at 28 weeks' gestation because of the compromised fetal condition. An autopsy revealed a rare malformation of intrahepatic bile ducts known as ductal plate malformation.</p> <p>Conclusion</p> <p>Persistent reverse flow in the middle cerebral artery should be considered a marker of adverse pregnancy outcome. We recommend careful ultrasound monitoring in the presence of this ultrasonographic sign to exclude any other cause of increased intracranial pressure. To better understand the nature of these ultrasonographic signs, additional reports are deemed necessary. In fact in our case, as confirmed by histopathological examination, the fetal condition was extremely compromised due to failure of the fetal liver. Ductal plate malformation altered the liver structures causing hypoproteinemia and probably portal hypertension. These two conditions therefore explain the severe hydrops that compromised the fetal situation.</p

Structural, Magnetic and Transport Properties of Single-Crystalline U2Pt2In.

Single-crystals of the heavy-electron compound U2Pt2In have been grown aby a modified mineralization techniuqe. The X-ray structure refinement shows that U2Pt2In single-crystals form in the Zr3Al2 structure, instead of the U3Si2 structure reported for polycrystalline material.The polymorphism of U2Pt2In is attributed to the experimental parameters, like pressure and temperature, during the sample preparation process. The single-crystal susceptibility data reveal a weak maximum for Chi c at Tmax= 7.9K, indicating the presence of short-range antiferromagnetic correlations, while Chi a has the tendency to diverge at low T (T>2K). The electrical resistivity of the single-crystals (T>0.3 K) is bestdescribed by p~Talpha with alpha~1.1(1) for I IIa and alpha~0.3(2) for I IIc. The magnetic and transport data show pronounced deviations from the standard Fermi-liquid picture, and lead to a classification of U2Pt2In as a non-Fermi liquid compound. As the origin of NFL behaviour in U2Pt2In we propose the proximity to a quantum critical point or Kondo disorder.JRC.E-Institute for Transuranium Elements (Karlsruhe

Conformational and Coordination Equilibria on DOTA Complexes of Lanthanide Metal Ions in Aqueous Solution Studied by 1H-NMR Spectroscopy

A variable-temperature, -pressure, and -ionic strength 1H NMR study of the DOTA complexes of different trivalent cations (Sc, Y, La, Ce → Lu) (DOTA = 1,4,7,10-tetraaza-1,4,7,10-tetrakis(carboxymethyl)cyclododecane) yielded data that are in contradiction with the hitherto used model of only two enantiomeric pairs of diastereoisomers that differ in the ligand conformations. A two-isomer equilibrium cannot explain the newly observed apparent reversal of the isomer ratio at the end of the series. As both conformers may lose their inner sphere water molecule, a coordination equilibrium may be superimposed on this conformational equilibrium, as shown by large positive reaction volumes for the isomerization of [Ln(DOTA)(H2O)x]- (Ln = Yb, Lu; x = 1, 0). The isomerization of [Nd(DOTA)(H2O)]- and [Eu(DOTA)(H2O)]- is purely conformational, as shown by near-zero reaction volumes. The measured isomerization enthalpies and entropies agree with this model. The shift of the isomerization equilibria by a variety of non-coordinative salts depends on the ligand conformation rather than the presence or absence of the inner sphere water molecule. This results from weak ion binding and water solvent stabilization of one ligand conformation, rather than the decrease of the activity of the bulk water in the solution, as shown by UV−vis measurements of the coordination number sensitive transition 5F0 → 7D0 of Eu(III) as a function of ionic strength. Fluoride ions replace a water molecule in the inner coordination sphere, preferentially for one of the conformational isomers, as proven by 19F-NMR shifts and the appearance of a third set of resonances corresponding to [Eu(DOTA)F]2- in the 1H-NMR spectrum of [Eu(DOTA)(H2O)]-

Heavy fermion behavior of U2T2X compounds

Magnetic and specific-heat studies of U2T2X compounds show a frequent occurrence of the gamma enhancement in conjunction with the onset of antiferromagnetic ordering. The largest value of 830 mJ/mol K**2 was observed in U2Pt2In, which is nonmagnetic down to 1.2 K. Variations of electronic structure are documented by optimized relativistic LCAO calculation