Dilution effects on combined magnetic and electric dipole interactions: A study of ferromagnetic cobalt nanoparticles with tuneable interactions.

Improved understanding of complex interactions between nanoparticles will facilitate the control over the ensuing self-assembled structures. In this work, we consider the dynamic changes occurring upon dilution in the self-assembly of a system of ferromagnetic cobalt nanoparticles that combine magnetic, electric, and steric interactions. The systems examined here vary in the strength of the magnetic dipole interactions and the amount of point charges per particle. Scattering techniques are employed for the characterization of the self-assembly aggregates, and zeta-potential measurements are employed for the estimation of surface charges. Our experiments show that for particles with relatively small initial number of surface electric dipoles, an increase in particle concentration results in an increase in diffusion coefficients; whereas for particles with relatively high number of surface dipoles, no effect is observed upon concentration changes. We attribute these changes to a shift in the adsorption/desorption equilibrium of the tri-n-octylphosphine oxide (TOPO) molecules on the particle surface. We put forward an explanation, based on the combination of two theoretical models. One predicts that the growing concentration of electric dipoles, stemming from the addition of tri-n-octylphosphine oxide (TOPO) as co-surfactant during particle synthesis, on the surface of the particles results in the overall repulsive interaction. Secondly, using density functional theory, we explain that the observed behaviour of the diffusion coefficient can be treated as a result of the concentration dependent nanoparticle self-assembly: additional repulsion leads to the reduction in self-assembled aggregate size despite the shorter average interparticle distances, and as such provides the growth of the diffusion coefficient.

Immediate delivery or expectant management in gestational diabetes at term: the GINEXMAL randomised controlled trial.

OBJECTIVE: To evaluate maternal and perinatal outcomes after induction of labour versus expectant management in pregnant women with gestational diabetes at term. DESIGN: Multicentre open-label randomised controlled trial. SETTING: Eight teaching hospitals in Italy, Slovenia, and Israel. SAMPLE: Singleton pregnancy, diagnosed with gestational diabetes by the International Association of Diabetes and Pregnancy Study Groups criteria (IADPSGC), between 38+0 and 39+0 weeks of gestation, without other maternal or fetal conditions. METHODS: Patients were randomly assigned to induction of labour or expectant management and intensive follow-up. Data were analysed by 'intention to treat'. MAIN OUTCOME MEASURES: The primary outcome was incidence of caesarean section. Secondary outcomes were maternal and perinatal mortality and morbidity. RESULTS: A total of 425 women were randomised to the study groups. The incidence of caesarean section was 12.6% in the induction group versus 11.7% in the expectant group. No difference was found between the two groups (relative risk, RR 1.06; 95% confidence interval, 95% CI 0.64-1.77; P = 0.81). The incidence of non-spontaneous delivery, either by caesarean section or by operative vaginal delivery, was 21.0 and 22.3%, respectively (RR 0.94; 95% CI 0.66-1.36; P = 0.76). Neither maternal nor fetal deaths occurred. The few cases of shoulder dystocia were solved without any significant birth trauma. CONCLUSIONS: In women with gestational diabetes, without other maternal or fetal conditions, no difference was detected in birth outcomes regardless of the approach used (i.e. active versus expectant management). Although the study was underpowered, the magnitude of the between-group difference was very small and without clinical relevance. TWEETABLE ABSTRACT: Immediate delivery or expectant management in gestational diabetes at term?

The associations between early pregnancy lipid profiles and pregnancy outcomes.

OBJECTIVE: To evaluate the association between early pregnancy lipid profiles and pregnancy outcomes. STUDY DESIGN: Retrospective 6 months analysis of 5218 singleton pregnant women. Each participant's demographic and medical data were collected by questionnaires and medical records. Total cholesterol (TC), triglycerides (TG), high-density lipid cholesterol (HDL-C) and low-density lipid cholesterol (LDL-C) levels were divided into quartiles, and the women were categorized as having low (<25th percentile), referent (25 to <75th percentile) or high (>75th percentile) TC, TG, HDL-C and LDL-C values. Differences between groups were tested using t-test and Pearson's χ2-test. Binary logistic regression and multivariate analysis was conducted to evaluate the associations between lipid values and the risk of pregnancy outcomes. RESULTS: (1) Women who subsequently developed adverse pregnancy outcomes had higher levels of TC, TG, LDL-C and lower levels of HDL-C during early pregnancy (<14 gestational weeks). (2) A trend toward an increasing incidence of adverse pregnancy outcomes was noted with increasing levels of TC, TG and LDL-C, and decreasing level of HDL-C. (3) The more numbers of TC, TG and LDL-C above 75th percentile and HDL-C inferior to 25th percentile women had, the higher their risk of developing adverse pregnancy outcomes. (4) Low TG level was a protective factor for gestational diabetes mellitus (GDM) (<1.44 mmol l-1, odds ratio (OR)=0.706, 95% confidence interval (CI), 0.586 to 0.852) and large for gestational age infants (LGA) (<1.44 mmol l-1, OR=0.769, 95% CI, 0.631 to 0.936), and low LDL-C (<1.89 mmol l-1) level was protective factor for preterm birth. High TG (>1.40 mmol l-1, OR=1.327, 95% CI, 1.130 to 1.558), TC (>4.29 mmol l-1, OR=1.250, 95% CI, 1.062 to 1.471), and LDL-C (>2.62 mmol l-1, OR=1.25, 95% CI, 1.069 to 1.480) levels and a low HDL-C (<1.89 mmol l-1, OR=1.190, 95% CI, 1.007 to 1.405) level were associated with increased risk of GDM. A high TG (>1.40 mmol l-1, OR=1.550, 95% CI, 1.025 to 2.343) level was related to high risk of pre-eclampsia (PE), while a high LDL-C (>2.62 mmol l-1, OR=1.400, 95% CI, 1.100 to 1.781) level was risk factor for macrosomia. (5) After adjusting for confounders, early pregnancy TC was an independent risk factor for GDM (ajusted odds ratio [aOR]=1.184, 95% CI, 1.085 to 1.291), TG level was independently associated with the prevalence of GDM (aOR=1.253, 95% CI, 1.141 to 1.375) and PE (aOR=1.245, 95% CI, 1.023 to 1.516), and LDL-C level was significantly associated with risk of GDM (aOR=1.162, 95% CI, 1.052 to 1.283) and preterm birth (aOR=1.264, 95% CI, 1.065, 1.501). CONCLUSIONS: Early pregnancy high levels of TC, TG, LDL-C and low level of HDL-C may be predictive biomarkers for adverse pregnancy outcomes, while early pregnancy low TC, TG, LDL-C levels and high HDL-C levels could have some protective roles.

Relationship of maternal birth weight on maternal and neonatal outcomes: a multicenter study in Beijing.

OBJECTIVE: Birth weight is an important indicator for childhood and adulthood diseases. Published studies lack information on the relative contribution of women's own birth weight to the course of her pregnancy, not only for maternal but especially to neonatal outcome. The aim of the study was to evaluate the relationship of maternal birth weight on maternal and perinatal complications during pregnancy. STUDY DESIGN: Medical and obstetrical data were collected from 5479 women at 15 hospitals in Beijing, by a systemic cluster sampling survey conducted from 20 June 2013 to 30 November 2013. These women were categorized into five groups, according to their own birth weight: low birth weight (⩽2500 g, n=275), sub-optimal birth weight (2500 to 2999 g, n=1079), optimal birth weight (3000 to 3499 g, n=2590; 3500 to 3999 g, n=1085) and high birth weight (⩾4000 g, n=450). The occurrence of maternal and neonatal complications was recorded and compared among the groups. Statistical analysis was performed by SPSS 20.0 and values of P<0.05 were considered to be statistically significant. RESULTS: Low maternal birth weight was associated with higher rates of gestational diabetes mellitus (χ2=21.268, P=0.006) and hypertensive disorders (χ2=10.844, P=0.028). The latter association was strongest in women with a pre-pregnancy body mass index above 25 kg m-2. Low maternal birth weight was also associated with an apparently higher incidence of preterm labor (χ2=18.27, P=0.001) and hypertriglyceridemia (χ2=2.739, P=0.027) in pregnancy. An association between women with low birth weight and a significantly higher rate of small for gestational age infants (χ2=93.507, P<0.001) and low birth weight (χ2=36.256, P<0.001) was detected. High maternal birth weight was associated with an increased risk of pre-pregnancy overweight and obesity (P<0.001), as well as for large for gestational age infants (χ2=93.507, P<0.001) and macrosomia (χ2=72.594, P<0.001). CONCLUSIONS: In our study, high or low maternal birth weight was strongly associated with maternal and perinatal adverse pregnancy outcomes. This suggests that by controlling the birth weight of female infants among the normal range, adverse outcomes may be decreased in the future and for the following generations.

Intrapartum GBS screening and antibiotic prophylaxis: a European consensus conference.

Group B streptococcus (GBS) remains worldwide a leading cause of severe neonatal disease. Since the end of the 1990s, various strategies for prevention of the early onset neonatal disease have been implemented and have evolved. When a universal antenatal GBS screening-based strategy is used to identify women who are given an intrapartum antimicrobial prophylaxis, a substantial reduction of incidence up to 80% has been reported in the USA as in other countries including European countries. However recommendations are still a matter of debate due to challenges and controversies on how best to identify candidates for prophylaxis and to drawbacks of intrapartum administration of antibiotics. In Europe, some countries recommend either antenatal GBS screening or risk-based strategies, or any combination, and others do not have national or any other kind of guidelines for prevention of GBS perinatal disease. Furthermore, accurate population-based data of incidence of GBS neonatal disease are not available in some countries and hamper good effectiveness evaluation of prevention strategies. To facilitate a consensus towards European guidelines for the management of pregnant women in labor and during pregnancy for the prevention of GBS perinatal disease, a conference was organized in 2013 with a group of experts in neonatology, gynecology-obstetrics and clinical microbiology coming from European representative countries. The group reviewed available data, identified areas where results were suboptimal, where revised procedures and new technologies could improve current practices for prevention of perinatal GBS disease. The key decision issued after the conference is to recommend intrapartum antimicrobial prophylaxis based on a universal intrapartum GBS screening strategy using a rapid real time testing.

In vitro simulation of placental transport: part II. Glucose transfer across the placental barrier model.

INTRODUCTION: In utero fetal development and fetal programming for adulthood life are strongly associated with maternal-to-fetal transfer of nutrient and other substances. Gestational diabetes mellitus (GDM) is a major problem and associated with abnormal fetal development, but the mechanisms underlying glucose transport across the placenta barrier (PB) are not completely understood. METHODS: We developed a placenta simulator that can mimic feto-maternal blood circulations along with real transfer across the in vitro biological model of the PB, which is made of a co-culture of endothelial cells (EC) and trophoblast cells (TC) on both sides of a denuded amniotic membrane (AM). Maternal-to-fetal transfer of glucose was monitored over 24 h. RESULTS: The AM is highly permeable to glucose compared to the cellular structures and can serve as a substrate for the co-culture model. The transfer characteristics for glucose are independent of its initial concentration in the maternal compartment, but strongly dependent on the cellular components of the PB. The EC are more resistive to glucose transfer than the TC. The in vitro PB model is the most resistive to glucose transfer. DISCUSSION AND CONCLUSION: The good correlation between the present in vitro results with existing in vivo data demonstrated the potential of this new approach, which can be extended to study various aspects of transplacental transfer, including medications, relevant to GDM or any problem related to in utero programing.

Technology and pregnancy.

The World Health Organisation projects that the number of diabetes-related deaths will double between the years 2005 and 2030. An important method for reducing the number of new cases of diabetes is by screening for and controlling glucose in women with gestational diabetes, the form of diabetes that afflicts up to 10% of the pregnant population. Uncontrolled gestational diabetes mellitus results in an increased risk of complications due to maternal hyperglycaemia and the resultant fetal hyperinsulinaemia. These complications include macrosomia and an increased risk of metabolic disorders including diabetes later in the child's life. Advances in the treatment of gestational diabetes have shown promising results in minimising fetal complications; they have also helped to slow the vicious cycle of women who contract gestational diabetes mellitus producing children with a high risk of developing diabetes later in life. A comprehensive literature review with an emphasis on technology has resulted in the following collection of papers relating to pregnancy and diabetes. Last year there were several technological advances in glucose monitoring. This year the applications of telemedicine in the treatment of gestational diabetes and the use of ultrasound for early detection of the disease have been at the forefront. The authors aimed to include articles that were not only relevant to the field of diabetes technology in pregnancy, but that also improved treatment and advanced understanding. The study design and results were also carefully examined in considering the articles. The selected articles contain findings that provide new techniques for diagnosing gestational diabetes mellitus as well as provide additional treatment methods for those affected by the disease.

Technology and pregnancy.

In the USA, depending upon the diagnosis criteria used, 135,000-200,000 women annually develop gestational diabetes mellitus, adding to the number of pregnant women already suffering from either type 1 or type 2 diabetes. Maternal hyperglycaemia and the resultant fetal hyperinsulinaemia are central to the pathophysiology of diabetic complications of pregnancy. These complications include congenital malformations and an increase in neonatal intensive care unit admission and birth trauma. In addition, there is an increased rate of accelerated fetal growth, neonatal metabolic complications and risk for stillbirth. Importantly, during the last century there were two breakthroughs in diabetes management and monitoring that changed the course of treatment: the discovery of insulin and the progress in the understanding of glucose monitoring. As technology has evolved, both glucose monitoring and insulin administration can now be achieved in a continuous fashion. In this review of the literature we focus on the utility of new technologies in the management and monitoring of diabetes in pregnancy.

Primary atherothrombotic occlusive vascular events in premenopausal women with history of adverse pregnancy outcome.

OBJECTIVE: To determine if adverse pregnancy outcomes are associated with atherothrombotic occlusive vascular disease (AOVD) in premenopausal women. DESIGN: Retrospective matched case-control study. SETTING: Tertiary, university-affiliated medical center. POPULATION: Women aged less than 50 years treated for an AOVD (primary cerebrovascular, myocardial, or peripheral arterial ischemic event) from 1995 to 2004. METHOD: The files were reviewed for classical risk factors for AOVD and complications of pregnancy (abortions, pregnancy-induced hypertension, preeclampsia, gestational diabetes, intrauterine growth restriction (IUGR), fetal loss and preterm delivery). Findings were compared with healthy women matched for age and body mass index. MAIN OUTCOME MEASURES: Past pregnancy complications in premenopausal women with AOVD. RESULTS: Of the 101 women with AOVD, 53 had a myocardial ischemic event, 33 a cerebrovascular event, and 15 a peripheral ischemic arterial event. On multivariate analysis, IUGR (OR 8.41, 95% CI 2.36-29.9, p=0.001) and more than one pregnancy complication (OR 13.7, 95% CI 1.56-120, p=0.02) were found to be independent significant variables associated with AOVD. CONCLUSION: IUGR and composite pregnancy complications are independent significant variables associated with AOVD in premenopausal period. Pregnancy outcome might serve as a means to identify patients who may require increased medical surveillance and preventive measures for later vascular disease.

Prostaglandin E2 induction of labor for isolated oligohydramnios in women with unfavorable cervix at term.

OBJECTIVE: To evaluate the maternal and neonatal outcomes of pregnancies complicated with isolated oligohydramnios at term, managed by induction of labor. METHODS: We conducted a retrospective case-control study. 138 women with uncomplicated oligohydramnios at term [amniotic fluid index (AFI) < or =5 cm] and a low Bishop score (< or =6) underwent induction of labor with prostaglandin E2. These women were compared to 67 women who underwent induction of labor at 42 weeks' gestation and 276 women at low-risk pregnancy and spontaneous onset of labor, matched for parity and race. RESULTS: Cesarean section (CS) rate was similar in the study and the post-date group (17.4 and 17.9%, respectively), but significantly higher than the spontaneous labor group (5.8%, OR 3.42, 95% CI 1.75-6.68). No differences were found with other outcomes. CONCLUSION: Pregnancies with isolated oligohydramnios at term apparently are not at higher risk of perinatal complications, but induction of labor is associated with increased rate of CS.

Leptin, insulin, insulin-like growth factors and their binding proteins in cord serum: insight into fetal growth and discordancy.

OBJECTIVE: Singleton infants with intrauterine growth restriction have an adaptive hormonal profile characterized by decreased levels of IGF-1, IGF-2, IGFBP-3 and insulin and elevated levels of IGFBP-1 and IGFBP-2. This study examined the association between cord serum levels of six growth factors and anthropometric features at birth in twins in order to determine the intrauterine growth factor interactions and to characterize the specific hormonal profile of small discordant twins. DESIGN: Prevalent case-control study. PATIENTS: Twenty pairs of discordant twins (5 monozygotic, 15 dizygotic) and 20 pairs of concordant twins (6 monozygotic, 14 dizygotic) matched for gestational age. MEASUREMENTS: Cord blood levels of IGF-1, IGF-2, IGFBP-1, IGFBP-3, insulin, leptin and anthropometric measurements at birth. Intra- and inter-pair differences and correlation coefficients were calculated, and the data were fitted to multivariate regression models. RESULTS: In both discordant and concordant groups, the smaller twins had a significantly lower level of IGF-1 (P < 0.03) and significantly higher level of IGFBP-1 (P < 0.02) than their larger cotwins. IGFBP-1 was inversely correlated with IGF-1 (P < 0.05). Insulin levels were significantly higher in the smaller discordant than the smaller concordant twins (P < 0.001) and in the larger discordant than the larger concordant twins (P < 0.004). Among the monozygotic twins, the leptin level was significantly higher in the larger discordant than the larger concordant twins (P < 0.025). Percentage birth weight discordancy was statistically correlated with twin-pair differences in IGF-1 and IGFBP-1. CONCLUSIONS: Of the six factors studied, IGF-1 appears to be the main indicator of intrauterine growth. Twin discordancy may involve compensatory rather than adaptive mechanisms or a multihormone relative resistance syndrome.

Pregnancy outcome of diabetic women 15 years after the St. Vincent declaration: success or failure?

No disponible

The pharmacologic approach to the prevention of preeclampsia: from antiplatelet, antithrombosis and antioxidant therapy to anticonvulsants.

Preeclampsia has been suggested to be a two-stage disorder of an alteration in placental perfusion (stage 1) leading to generalized vascular endothelial damage (stage 2). Because the mechanism linking the two stages remains unclear, effective primary prevention is still impossible. However, advances made in our understanding of the pathophysiology of preeclampsia have paved the way for secondary and tertiary prevention approaches. Platelets are known to be activated in early pregnancy. They also play a pivotal role in the process of inflammation, as demonstrated by the finding that CD40 ligand is shed from activated platelets to directly initiate inflammation of the vessel wall. According to the Cochrane Library Update summarizing data from over 30,000 women, secondary prevention with antiplatelet drugs is associated with a 19% decrease in the risk of preeclampsia. Additional randomized controlled trials are needed to establish the association between preeclampsia and thrombophilia. The effect of the antithrombotic agent heparin on pregnancy outcome in preeclampsia and its potential preventive action in high-risk patients need to be elucidated. One of the several hypotheses of the pathogenesis of preeclampsia focuses on the oxidative stress caused by the imbalance in prooxidant and antioxidant forces. Preliminary findings on vitamin E and vitamin C supplementation in preeclamptic women are encouraging, and suggest a rationale for larger clinical trials. Although there is currently no explanation for the positive effect of magnesium sulfate on eclamptic seizures, studies have provided enough evidence to encourage its worldwide use as the primary anticonvulsant of choice in the tertiary prevention of maternal and perinatal death in severe preeclampsia/eclampsia. In conclusion, secondary and tertiary prevention of preeclampsia is possible when targeted at reducing maternal and neonatal morbidity and mortality.

Maternal and fetal outcome of lupus pregnancy: a prospective study of 29 pregnancies.

The aim of this study was to analyse pregestational and pregnancy risk factors for adverse fetal and maternal outcome in lupus pregnancy. Twenty women with systemic lupus erythematosus (SLE) (29 pregnancies) were prospectively evaluated. Mean patient age was 29.5+/-4.7 years, and mean disease duration, 6.3+/-6.5 years. Twenty-two pregnancies (75.9%) ended in live births; preterm delivery occurred in 17.4%, intrauterine growth restriction in 50%, preeclampsia in 3.7%, and gestational hypertension in 8%. Six pregnancies (20.7%) ended in spontaneous abortions. Adverse live-birth outcome was significantly associated with low pregestational serum albumin level, elevated gestational anti-dsDNA antibody, and diabetes mellitus. Spontaneous abortion was directly associated with low levels of pregestational serum albumin, positive anticardiolipin IgA, anti-beta2-glycoprotein I IgM, and anti-La antibodies, and inversely associated with number of patients' children. Postgestational lupus flare-up was noted in six pregnancies. Risk factors included high pregestational SLE Disease Activity Index (SLEDAI), lower serum albumin, elevated serum antibody to dsDNA, proteinuria, and use of prednisone and hydroxychloroquine. We conclude that despite high rate of obstetrical complications and postpartum lupus flare-up, pregnancy poses low risk for the majority of women with SLE.

Serum and follicular fluid leptin levels in patients undergoing controlled ovarian hyperstimulation for in vitro fertilization cycle.

OBJECTIVE: To determine serum and follicular fluid leptin levels in patients undergoing controlled ovarian hyperstimulation (COH) for an in vitro fertilization-embryo transfer (IVF-ET) cycle and their possible correlation to COH variables. SETTING: Large university-based IVF unit. PATIENTS: 16 consecutive patients undergoing our routine IVF long gonadotrophin-releasing hormone-analog protocol. INTERVENTIONS AIND MAIN OUTCOME MEASURES: Blood was drawn three times during the COH cycle: 1) day on which adequate suppression was obtained (Day-S); 2) day of or prior to human chorionic gonadotrophin (hCG) administration (Day-hCG); and 3) day of ovum pick-up (Day-OPU). Levels of sex steroids and serum and follicular fluid leptin were compared among the three time points. Serum leptin was measured with a commercial two-site immunoradiometric assay. RESULTS: Results showed significantly higher levels of serum leptin on Day-OPU and Day-hCG than on Day-S, and significantly higher follicular than serum leptin levels on Day-OPU. Though a significant correlation was observed between serum leptin and body mass index (BMI), no correlations were found between serum or follicular fluid leptin and serum sex-steroid levels or IVF treatment variables. CONCLUSION: While serum leptin increases during COH for IVF, there is apparently no correlation of serum and follicular leptin levels with sex-steroid levels or IVF outcome.

Accuracy of sonographically estimated fetal weight in 840 women with different pregnancy complications prior to induction of labor.

OBJECTIVES: To evaluate the accuracy of sonographically estimated fetal weight (EFW) shortly before induction of labor in the presence of different pregnancy complications, and to define possible variables affecting it. METHODS: The study sample consisted of 840 women with singleton pregnancies and cephalic presentation who were admitted to our unit for induction of labor between January 1999 and December 2000. All underwent detailed ultrasound assessment for EFW, amniotic fluid index, biophysical profile and placental location. Indications included previous Cesarean section, postdate pregnancy, pregnancy-induced hypertension, diabetic pregnancy, suspected large-for-gestational age (LGA) infants, suspected fetal growth restriction (FGR), oligohydramnios, decreased fetal movements, premature rupture of membranes at or before term. EFW was calculated after measuring fetal abdominal circumference and femur length. The EFW was compared with the weight at delivery, 1-3 days later. RESULTS: There was a high correlation between EFW and birth weight (R(2) = 0.775, P < 0.001). The mean birth weight was 3207 +/- 561 g, and mean absolute weight difference was 227 +/- 197 g; (absolute range, 0-1700 g; actual range, - 986 to + 1700 g). The mean weight difference was significantly different between the patients with LGA infants, FGR infants and preterm premature rupture of membranes (PPROM) (- 110 +/- 281 g, + 113 +/- 195 g and + 115 +/- 307 g, respectively, P < 0.01). Stepwise linear regression analysis of the effects of maternal and pregnancy characteristics on the weight difference yielded lower gestational age, higher birth weight, anterior placenta, higher gravidity, and younger maternal age as independent and significant variables associated with greater actual weight difference inaccuracy (R(2) = 0.099, P < 0.001), and higher birth weight as the only independent and significant variable associated with greater absolute weight difference (R(2) = 0.09, P = 0.018). CONCLUSIONS: The sonographic EFW is highly correlated with birth weight. However, clinicians should be aware of the risk of overestimation in pregnancies with suspected LGA and underestimation in pregnancies with PPROM and suspected FGR.