Uterine artery Doppler and sFlt-1/PlGF ratio: usefulness in diagnosis of pre-eclampsia

OBJECTIVE

To evaluate the usefulness of the mean pulsatility index of the uterine arteries (mPI-UtA) and automated measurement of the soluble fms-like tyrosine kinase 1 (sFlt-1)/placental growth factor (PlGF) ratio on suspicion or at diagnosis of pre-eclampsia (PE).

METHODS

Patients with singleton pregnancies with PE (n = 60) diagnosed according to current recommendations, or with suspected PE (n = 32) defined by (1) blood pressure (BP) ≥ 160/100 mmHg, (2) BP ≥ 140/90 mmHg or proteinuria, together with suggestive clinical symptoms or (3) intrauterine growth restriction (IUGR) at < 34 + 0 weeks, were enrolled and mPI-UtA and the sFlt-1/PlGF ratio were measured. Values > 95(th) centile were considered abnormal. All cases were classified according to occurrence of PE and/or IUGR and subclassified, depending on gestational age at delivery, as early (< 34 + 0 weeks) or late (≥ 34 + 0 weeks).

RESULTS

PE was confirmed in 72 cases, in which 32 early deliveries occurred. Isolated IUGR was diagnosed in nine early cases and one late case, while the remaining 10 cases were late deliveries without PE or IUGR. In pregnancies in which PE and IUGR were excluded, mPI-UtA was abnormal in 40% but the sFlt-1/PlGF ratio was normal in 100%. In early PE, mPI-UtA at diagnosis was abnormal in 100% of cases with IUGR and in 91% without IUGR, while sFlt-1/PlGF was abnormal in 100% and 96%, respectively. In late PE, mPI-UtA was abnormal in 50% and 37% of cases with and without IUGR while the sFlt-1/PlGF ratio was abnormal in 50% and 26%, respectively.

CONCLUSION

Abnormal mPI-UtA and sFlt-1/PlGF ratio are common in early PE. In late PE, mPI-UtA is normal in most cases and thus not diagnostically useful. The sFlt-1/PlGF ratio shows high specificity but low sensitivity to confirm PE when suspected.

Polidocanol foam stability in terms of its association with glycerin

Objectives:

Foam sclerotherapy effectiveness mainly depends on the concentration of the sclerosing agent and foam stability. The objective of this study was to determine if the addition of glycerol at different concentrations contributes to the stability of polidocanol foam.

Materials and methods:

Control Group: 3% polidocanol. Group 1: polidocanol 3% + glycerin 1.66%. Group 2: polidocanol 3% + glycerin 3.3%. Group 3: polidocanol 3% + Glycerin 5%. Tessari standard method. Five recordings were made for each mixture. Early visual liquefaction time and half liquid time decay were recorded in seconds. Microscopic measurement of the foams. Mixtures surface tension measurement (N/m).

Results:

Early visual liquefaction: Control Group: 27 (± 3.11); Group 1: 67.8 (± 6.49); Group 2:48.6 (± 8.2); and Group 3: 35.8 (± 4.49). Half-liquid time: Control: 129.2 (± 11.00); Group 1: 260.4 (±18.99); Group 2: 224.6 (±13.03); and Group 3: 189.2 (±8.52). Bubbles/mm2–diameter–wall thickness: Control: 68–98 μm-7 μm; Group 1: 189–60 μm-9 μm; Group 2: 76–92 μm-12 μm; and Group 3: 49–112 μm-20 μm. Surface tension: Control = 5.54 N/m; Group 1 = 5.45 N/m; Group 2 = 5.35 N/m; and Group 3 = 5.21 N/m.

Conclusions:

Small amounts of glycerin highly increase the stability and quality of polidocanol foam. This simple chemical method is easily reproducible and applicable.

Pseudo hard-sphere potential for use in continuous molecular-dynamics simulation of spherical and chain molecules

We present a continuous pseudo-hard-sphere potential based on a cut-and-shifted Mie (generalized Lennard-Jones) potential with exponents (50, 49). Using this potential one can mimic the volumetric, structural, and dynamic properties of the discontinuous hard-sphere potential over the whole fluid range. The continuous pseudo potential has the advantage that it may be incorporated directly into off-the-shelf molecular-dynamics code, allowing the user to capitalise on existing hardware and software advances. Simulation results for the compressibility factor of the fluid and solid phases of our pseudo hard spheres are presented and compared both to the Carnahan-Starling equation of state of the fluid and published data, the differences being indistinguishable within simulation uncertainty. The specific form of the potential is employed to simulate flexible chains formed from these pseudo hard spheres at contact (pearl-necklace model) for m(c) = 4, 5, 7, 8, 16, 20, 100, 201, and 500 monomer segments. The compressibility factor of the chains per unit of monomer, m(c), approaches a limiting value at reasonably small values, m(c) < 50, as predicted by Wertheim's first order thermodynamic perturbation theory. Simulation results are also presented for highly asymmetric mixtures of pseudo hard spheres, with diameter ratios of 3:1, 5:1, 20:1 over the whole composition range.

Expanded allogeneic adipose-derived stem cells (eASCs) for the treatment of complex perianal fistula in Crohn's disease: results from a multicenter phase I/IIa clinical trial

PURPOSE

The management of perianal fistula in patients with Crohn's disease is an extremely challenging medical problem as many fistulas do not respond to available treatments. The objectives were to assess the safety and efficacy of a suspension of expanded adipose-derived allogeneic mesenchymal stem cells (eASCs) for the treatment of complex perianal fistula in Crohn's disease

METHODS

An open-label, single-arm clinical trial was conducted at six Spanish hospitals. Twenty-four patients were administered intralesionally with 20 million eASCs in one draining fistula tract. A subsequent administration of 40 million eASCs was performed if fistula closure was incomplete at week 12. Subjects were followed until week 24 after the initial administration.

RESULTS

Treatment-related adverse events did not indicate any clinical safety concerns after 6 months follow-up. The full analysis of efficacy data at week 24 showed 69.2 % of the patients with a reduction in the number of draining fistulas, 56.3 % of the patients achieved complete closure of the treated fistula achieved, and 30 % of the cases presenting complete closure of all existing fistula tracts. Of note, closure was strictly defined as: absence of suppuration through the external orifice and complete re-epithelization, plus absence of collections measured by magnetic resonance image scan (MRI). Furthermore, MRI Score of Severity showed statistically significant differences at week 12 with a marked reduction at week 24.

CONCLUSIONS

Locally injected eASCs appear to be a simple, safe, and beneficial therapy for perianal fistula in Crohn's disease patients. Additional studies are needed to further confirm the efficacy of the eASCs.

Prediction of coarctation of the aorta in the second half of pregnancy

OBJECTIVE

To determine which combination of cardiac parameters provides the best prediction of postnatal coarctation of the aorta (CoAo) in fetuses with cardiac asymmetry.

METHODS

We selected all cases of disproportion of the ventricles and great vessels prenatally diagnosed between 2003 and 2010 at the Hospital Universitario '12 de Octubre', Madrid, Spain. Only appropriate-for-gestational age liveborn fetuses with isolated cardiac asymmetry and with complete postnatal follow-up were included in the study. Eighty-five cases were retrieved and analyzed. Logistic regression analysis was used to select the best predictors of CoAo. Optimal cut-offs for these parameters were identified and the corresponding likelihood ratios used to calculate the post-test probability of CoAo in each fetus.

RESULTS

CoAo was confirmed in 41/85 neonates (48%). The parameters selected by logistic regression and their cut-off values were: gestational age at diagnosis ≤ 28 weeks, Z-score of diameter of the ascending aorta ≤ -1.5, pulmonary valve/aortic valve diameters ratio ≥ 1.6 and Z-score of the aortic isthmus diameter in the three vessels and trachea view ≤ -2. We divided the study group into two subgroups: Group A, in whom the diagnosis was made at ≤ 28 weeks' gestation (80% CoAo (32/40)); and Group B, in whom the diagnosis was made at > 28 weeks (20% CoAo (9/45)). The mean post-test probabilities of CoAo were higher in fetuses with CoAo than in normal fetuses in both subgroups (Group A, 82 vs 55%; P = 0.002 and Group B, 51 vs 20%; P < 0.001). In addition, a rate of growth of the aortic valve of ≤ 0.24 mm/week provided 80% sensitivity and 100% specificity for predicting CoAo in Group A.

CONCLUSIONS

We have derived a multiparametric scoring system, combining size-based cardiac parameters and gestational age at diagnosis, which may improve the accuracy of fetal echocardiography for the stratification of the risk of CoAo. The objectivity and simplicity of its components may allow its implementation in fetal cardiology units.

SAFT-γ force field for the simulation of molecular fluids: 2. Coarse-grained models of greenhouse gases, refrigerants, and long alkanes

In the first paper of this series [C. Avendaño, T. Lafitte, A. Galindo, C. S. Adjiman, G. Jackson, and E. A. Müller, J. Phys. Chem. B2011, 115, 11154] we introduced the SAFT-γ force field for molecular simulation of fluids. In our approach, a molecular-based equation of state (EoS) is used to obtain coarse-grained (CG) intermolecular potentials that can then be employed in molecular simulation over a wide range of thermodynamic conditions of the fluid. The macroscopic experimental data for the vapor-liquid equilibria (saturated liquid density and vapor pressure) of a given system are represented with the SAFT-VR Mie EoS and used to estimate effective intermolecular parameters that provide a good description of the thermodynamic properties by exploring a wide parameter space for models based on the Mie (generalized Lennard-Jones) potential. This methodology was first used to develop a simple single-segment CG Mie model of carbon dioxide (CO2) which allows for a reliable representation of the fluid-phase equilibria (for which the model was parametrized), as well as an accurate prediction of other properties such as the enthalpy of vaporization, interfacial tension, supercritical density, and second-derivative thermodynamic properties (thermal expansivity, isothermal compressibility, heat capacity, Joule-Thomson coefficient, and speed of sound). In our current paper, the methodology is further applied and extended to develop effective SAFT-γ CG Mie force fields for some important greenhouse gases including carbon tetrafluoride (CF4) and sulfur hexafluoride (SF6), modeled as simple spherical molecules, and for long linear alkanes including n-decane (n-C10H22) and n-eicosane (n-C20H42), modeled as homonuclear chains of spherical Mie segments. We also apply the SAFT-γ methodology to obtain a CG homonuclear two-segment Mie intermolecular potential for the more challenging polar and asymmetric compound 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf), a novel replacement refrigerant with promising properties. The description of the fluid-phase behavior and the prediction of the other thermophysical properties obtained by molecular simulation using our SAFT-γ CG Mie force fields are found to be of comparable quality (and sometimes superior) to that obtained using the more sophisticated all-atom (AA) and united-atom (UA) models commonly employed in the field. We should emphasize that though the focus of our current work is on simple homonuclear models, the SAFT-γ methodology is based on a group contribution methodology which is naturally suited to the development of more sophisticated heteronuclear models.

Leaf mechanisms for drought resistance in Zizyphus jujuba trees

No information exists on the mechanisms developed at the level of leaf water relations by pear-jujube trees (Zizyphus jujuba Mill.) to confront drought. For this reason, the purpose of the present study was to analyse its leaf water relations in order to clarify the resistance mechanisms (avoidance and tolerance) developed in response to a water stress and during recovery. Field-grown 7-year-old pear-jujube trees (cv. Grande de Albatera) were subjected to three irrigation treatments. Control (T0) plants were drip irrigated (112% ETo) in order to guarantee non-limiting soil water conditions, T1 plants (deficit irrigation, 64% ETo) were drip irrigated according to the criteria used by the grower and T2 plants irrigated as T0 but subjected to water withholding for 36 days and a subsequent re-irrigation at the levels used in T0 for 14 days, during the summer of 2011. The results indicated that pear-jujube plants confront water stress by developing stress avoidance and stress tolerance mechanisms. From the beginning of deficit irrigation (T1) and water withholding (T2) to when maximum water stress levels were achieved, leaf turgor was maintained allowing substantial gas exchange levels and, consequently, good leaf productivity. This leaf turgor maintenance was mainly due to two simultaneous and complementary mechanisms. Leaf conductance and the duration of maximum stomatal opening in water stressed plants decreased in order to control water loss via transpiration, contributing to maintain leaf turgor (stress avoidance mechanisms). Also, the gradual recovery of g(l) observed after rewatering the plants can be considered as a mechanism for promoting leaf rehydration. In addition, from the beginning of the stress period, active osmotic adjustment operated, also contributing to the maintenance of leaf turgor (stress tolerance mechanism). The high RWC(a) levels and the possibility of increasing the accumulation of water in the apoplasm in response to water stress, supporting a steeper gradient in water potential between the leaf and the soil, which can be considered another drought tolerance characteristic in pear-jujube.

Predictive value of sequential models of uterine artery Doppler in pregnancies at high risk for pre-eclampsia

OBJECTIVE

To evaluate the performance of models described previously for the prediction of pre-eclampsia (PE), based on the sequential evaluation of uterine artery resistance at 11-13 weeks and 19-22 weeks, in a high-risk population.

METHODS

This was a prospective study in 135 women with singleton pregnancies and at least one of the following high-risk conditions: PE and/or intrauterine growth restriction in a previous pregnancy, chronic hypertension, pregestational diabetes, renal disease, body mass index > 30 kg/m(2) , autoimmune disease (systemic lupus erythematosus, antiphospholipid syndrome or rheumatoid arthritis) and thrombophilia. Mean uterine artery pulsatility index (mUtA-PI) at 11-13 and at 19-22 weeks' gestation was measured and analyzed according to quantitative and semi-quantitative models, to predict late PE (resulting in delivery ≥ 34 weeks) and early PE (delivery < 34 weeks).

RESULTS

Late PE developed in 21 (15.6%) pregnancies and early PE in six (4.4%). Using mUtA-PI, the detection rates of late and early PE for a false-positive rate of 10% were 14.3% and 33.3%, respectively, at 11-13 weeks, and 19.0% and 66.7%, respectively, at 19-22 weeks. Using a semi-quantitative approach, the group of pregnant women with mUtA-PI ≥ 90(th) percentile at both 11-13 and 19-22 weeks had a greater risk for early PE (odds ratio, 21.4 (95% CI, 2.5-184.7)) compared with the group with mUtA-PI < 90(th) percentile at both periods. Using a quantitative approach, there was relative worsening in the mUtA-PI (multiples of the median) from the first to the second trimester in all cases of early PE.

CONCLUSION

The application of semi-quantitative and especially quantitative models to evaluate sequential changes in uterine artery Doppler findings between the first and second trimesters could be of additional value in assessing high-risk women regarding their true risk of developing early PE.

Anomalous columnar order of charged colloidal platelets

Monte Carlo computer simulations are carried out for a model system of like-charged colloidal platelets in the isothermal-isobaric ensemble (NpT). The aim is to elucidate the role of electrostatic interactions on the structure of synthetic clay systems at high particle densities. Short-range repulsions between particles are described by a suitable hard-core model representing a discotic particle. This potential is supplemented with an electrostatic potential based on a Yukawa model for the screened Coulombic potential between infinitely thin disklike macro-ions. The particle aspect-ratio and electrostatic parameters were chosen to mimic an aqueous dispersion of thin, like-charged, rigid colloidal platelets at finite salt concentration. An examination of the fluid phase diagram reveals a marked shift in the isotropic-nematic transition compared to the hard cut-sphere reference system. Several statistical functions, such as the pair correlation function for the center-of-mass coordinates and structure factor, are obtained to characterize the structural organization of the platelets phases. At low salinity and high osmotic pressure we observe anomalous hexagonal columnar structures characterized by interpenetrating columns with a typical intercolumnar distance corresponding to about half of that of a regular columnar phase. Increasing the ionic strength leads to the formation of glassy, disordered structures consisting of compact clusters of platelets stacked into finite-sized columns. These so-called "nematic columnar" structures have been recently observed in systems of charge-stabilized gibbsite platelets. Our findings are corroborated by an analysis of the static structure factor from a simple density functional theory.

Tetralogy of Fallot: prediction of outcome in the mid-second trimester of pregnancy

OBJECTIVE

To evaluate the usefulness of fetal echocardiography in the mid-second trimester in predicting postnatal outcome of tetralogy of Fallot (ToF), focusing on the need for early intervention (EI) and surgery type: pulmonary valve-sparing surgery (PVSS) versus placement of transannular patch (TAP).

METHODS

Assessment of cardiac morphological and functional parameters in 23 live-born fetuses with isolated ToF was performed at 19 to 22 and 34 to 38  weeks. Comparisons were made between outcome groups (EI vs non-EI and PVSS vs TAP). EI was considered as requirement either of palliative procedure or corrective surgery before three months.

RESULTS

Overall survival was 96%. EI was required in 32% of cases and TAP in 50%. At 19 to 22  weeks, a pulmonary valve peak systolic velocity (PVPSV) ≥87.5 cm/s predicted EI with 100% sensitivity and 93.3% specificity (p < 0.01). At 34 to 38  weeks, the size of the pulmonary valve, pulmonary valve/aortic valve and main pulmonary artery/ascending aorta were significantly different, but the PVPSV again yielded the best performance: all cases undergoing EI and/or TAP were selected using cut-off of ≥144.5 cm/s.

CONCLUSION

The postnatal outcome of fetuses with ToF may be established using PVPSV from the mid-second trimester. This may be useful in providing the most appropriate perinatal management and accurate parental counselling.

Congenital chylothorax: from foetal life to adolescence

AIM

To analyse the main prenatal and postnatal features of congenital chylothorax (CC), and the outcome including mid-term follow-up.

METHODS

We searched our databases for CC diagnosed between 1990 and 2006. Data of 29 cases were retrieved and analysed. Follow-up until 3 years of age was available for all patients.

RESULTS

Most patients were diagnosed prenatally (94%) and most cases were complicated by foetal hydrops (66.7%). The overall survival rate at 3 years was 56%. A significantly poorer outcome was observed when foetal hydrops, preterm birth < 34 weeks, large effusions and/or early-onset pneumothorax were present. An important but not significant improvement in the survival rate was observed through the study period; while in 1990-1998, the survival rate was 41.7%, from 1999 to 2006 it was 66.7% (p = 0.19). In the mid-term follow-up, we did not observe any recurrence of CC and most infants remain asymptomatic. However, 27% of survivors were diagnosed as having asthma in early infancy.

CONCLUSION

CC still carries a significant risk of perinatal mortality. However, continuous advances in foetal and neonatal medicine are improving the prognosis of these patients, and nowadays most of them are likely to survive. Beyond the neonatal period, most survivors have an uneventful outcome.