Estimation of diagnostic value of the middle cerebral artery peak systolic velocity in prediction of fetal anemia in pregnancies complicated by alloimmunisation

Abstract The use of the middle cerbral artery peak systolic velocity (PSV) for the noninvasive diagnosis of fetal anemia in pregnancies complicated by alloimmunisation has the potential to reduce the number of invesive procedures. Objectives: The study was undertaken to determine the detection of fetal anemia by fetal middle cerebral artery peak systolic velociy (MCA PSV). Material and methods: 31 fetuses with red cell alloimmunisation were evaluated with Doppler ultrasongraphy. On the basis of ROC (AUC) analysis the cutoff point of MoM=1.215 with the highest sensitivity and specivicity was established. We examined the relation between MoM=1.215 and neonatal hemoglobin level and the maternal antibody titre in the indirect antiglobulin test. Sensitivity, specificity, positive and negative value and statistical significance were calculated. Conclusions: Data reported to date suggest that a threshold of 1.215 multiples of the median can be used to better diagnostic of fetal anemia

Meningitis and chosen complications of neonatal period in preterm neonates born to single or multiple pregnancies

The aim of this study was to determine the relationship between meningitis and neonatal period of complications such as massive intraventricular hemorrhage and into brain tissue, hypoxic-ischemic white matter injury, retinopathy of prematurity 3-5º and deafness in infants born prematurely, from single and multiple pregnancies. Material: The retrospective study covered 460 preterm infants born to single pregnancies and 280 infants born prematurely with multiple pregnancies, hospitalized in the Clinic of Neonatology PUM in the years: 2005–2008. Results: There were no statistically significant differences between the frequency of occurrence: peri/intraventricular hemorrhages (IVH) IIIº and IVº, hypoxic-ischemic injury in white matter, retinopathy of prematurity 3-5º and hearing loss in newborns of both groups. Meningitis was diagnosed in 35 (7.92%) newborns from singleton pregnancy, and in 9 (3.25%) with a multiple pregnancy. It was found that the risk of meningitis was significantly greater in infants with body weight less than 1000 grams (OR 4.18), and born under 28 weeks of gestation (OR =5.07), regardless of group affiliation. We found a statistically significant correlation between the occurrence of meningitis and neonatal complications such as IVH IIIº and IVº (OR-5, 56), hypoxic-ischemic white matter injury (OR - 18.93) and retinopathy of prematurity (7.45) in newborns with both single and multiple pregnancies. There was no effect of meningitis on the incidence of hearing loss. Conclusion: There exists a significant association between the occurrence of meningitis and some neonatal complications such as massive intraventricular hemorrhage, hypoxic-ischemic changes in white matter of the brain and retinopathy of prematurity 3-5º, leading to disturbances in the further development of the prematurely born child. The incidence of meningitis in newborn infants is inversely proportional to the duration of pregnancy

Temperature Behavior of Aqueous Solutions of Poly(2-Oxazoline) Homopolymer and Block Copolymers Investigated by NMR Spectroscopy and Dynamic Light Scattering

1H NMR methods in combination with dynamic light scattering were applied to study temperature behavior of poly(2-isopropyl-2-oxazoline) (PIPOx) homopolymer as well as PIPOx-b-poly(2-methyl-2-oxazoline) (PMeOx) and poly(2-ethyl-2-oxazoline) (PEtOx)-b-PMeOx diblock copolymers in aqueous solutions. 1H NMR spectra showed a different way of phase transition for the main and side chains in PIPOx-based solutions. Additionally, the phase transition is irreversible for PIPOx homopolymer and partially reversible for PIPOx-b-PMeOx copolymer. As revealed by NMR, the phase transition in PEtOx-based copolymers solutions exists despite the absence of solution turbidity. It is very broad, virtually independent of the copolymer composition and reversible with some hysteresis. Two types of water molecules were detected in solutions of the diblock copolymers above the phase transition—“free” with long and “bound” with short spin–spin relaxation times T2. NOESY spectra revealed information about conformational changes observed already in the pre-transition region of PIPOx-b-PMeOx copolymer solution

High sensitivity spectroscopy of the O2 band at 1.27 µm: (I) Pure O2 line parameters above 7920 cm−1

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Synthesis and Impedance Spectroscopy of Poly(p-phenylenediamine)/Montmorillonite Composites

Poly(p-phenylenediamine)/montmorillonite (PPDA/MMT) composites were prepared by the oxidative polymerization of monomers intercalated within the MMT gallery, using ammonium peroxydisulfate as an oxidant. The intercalation process was evidenced by X-ray powder diffraction. The FT-IR and Raman spectroscopies revealed that, depending on the initial ratio between monomers and MMT in the polymerization mixture, the polymer or mainly oligomers are created during polymerization. The DC conductivity of composites was found to be higher than the conductivity of pristine polymer, reaching the highest value of 10−6 S cm−1 for the optimal MMT amount used during polymerization. Impedance spectroscopy was performed over wide frequency and temperature ranges to study the charge transport mechanism. The data analyzed in the framework of conductivity formalism suggest different conduction mechanisms for high and low temperature regions

Self-Catalyzed Coupling between Brønsted-Acidic Imidazolium Salts and Epoxy-Based Materials: A Theoretical/Experimental Study

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FROM AB INITIO CALCULATIONS TO SPECTRAL LINE SHAPE PARAMETRISATION FOR SPECTROSCOPIC DATABASES

International audienceHydrogen molecule in its ground electronic state perturbed by the helium atom constitutes the simplest system of molecule perturbed by atom. This gives possibility to make a link between the experiment and the theory from first principles. We utilize highly accurate cavity ring-down spectroscopy to study the H2-He collisions and interactions. In contrast to most of the previous studies, we directly superimpose theoretical profiles, originating from our ab initio calculations, on the experimental spectra without fitting any of the line-shape parameters. Within this approach not only the shapes of experimental lines are reliably reproduced, but also the underlying physics of molecular collisions can be traced. Besides the analysis of the basic line-shape effects (such as relaxation or phase changes of the internal states of the molecule), we also study the more sophisticated ones such as speed-dependent effects or velocity-changing collisions (complex Dicke narrowing parameter), which are particularly pronounced for the H2-He system. We achieved agreement at the 1% level between experimental data and ab initio calculations not reached before for any real system. In addition, we show that measured spectral line shapes can be interpolated within similar accuracy by Hartman-Tran line shape profile, which has been implemented as a standard for HITRAN database with β correction applied

Ionic Liquid-Silica Precursors via Solvent-Free Sol–Gel Process and Their Application in Epoxy-Amine Network: A Theoretical/Experimental Study

This work describes the solvent-free sol–gel synthesis of epoxy-functionalized silica-based precursors in the presence of 1-butyl-3-methylimidazolium-based ionic liquids (ILs) containing different anions: chloride (Cl^–) and methanesulfonate (MeSO₃^–). The IL-driven sol–gel mechanisms were investigated in detail using experimental characterizations (²⁹Si NMR and ATR FTIR spectroscopy) and a theoretical computational method based on density functional theory (DFT). We observed complex IL influence on both hydrolysis and condensation steps, involving especially H-bonding and Coulomb coupling stabilization of the process intermediates. The obtained IL–silica precursors and their further xerogels were widely characterized (rheology measurements, MALDI TOF, ²⁹Si NMR, ATR FTIR, and DFT simulation), which allowed observation of their precise silica structures and established their most energetically favorable conformations. The detected silica structures were dependent on the IL type and varied from highly condensed 3D cage-like to branched ladder-like and cyclic ones. The application of prepared IL–silica precursors as reinforcing additives into the epoxy–amine network led to an improvement in the organic/inorganic interphase interactions through chemical and physical bonding. Uniform and well-dispersed silica aggregates, in the size of ∼30 nm, were formed when ≤6.8 wt % of each IL–silica precursor was applied into the epoxy–amine network. The use of imidazolium-based ILs contributed to a significant improvement in thermomechanical properties of hybrids and reduced their UV absorption ability compared to that of the reference matrix. All hybrids exhibited an increase in energy to break (up to ∼53%), elongation at break (up to ∼43%), shear storage modulus in the rubbery region (up to 4 times), and thermo-oxidative stability