Association between fetal fraction on cell-free DNA testing and first-trimester markers for pre-eclampsia

OBJECTIVES

To evaluate the association between fetal fraction on cell-free DNA (cfDNA) testing and first-trimester markers for pre-eclampsia, and to investigate the possible association of low fetal fraction with increased risks for pre-eclampsia (PE) and fetal growth restriction (FGR).

METHODS

This was a retrospective cohort study including all women with a singleton pregnancy who had risk calculation for PE and FGR between 11 + 0 and 13 + 6 weeks' gestation and who also had cfDNA as a primary or secondary screening test for chromosomal abnormalities at any gestational age at two fetal medicine clinics in Sydney and Melbourne, Australia, between March 2013 and May 2017. Logarithmically transformed fetal fraction results were adjusted for gestational age and maternal characteristics. Associations with mean arterial pressure (MAP), mean uterine artery pulsatility index (UtA-PI), pregnancy-associated plasma protein A (PAPP-A), placental growth factor (PlGF), and risks for PE < 34 weeks, PE < 37 weeks and FGR < 37 weeks were analyzed using correlation analysis and univariable and multivariable linear regressions.

RESULTS

In total, 4317 singleton pregnancies that underwent cfDNA testing with fetal fraction reported were included. Significant prediction of fetal fraction was provided by gestational age, conception by in-vitro fertilization, maternal age, body mass index, chronic hypertension, diabetes mellitus, South Asian ethnicity and being parous without history of PE or FGR. Fetal fraction was associated inversely with MAP and UtA-PI and associated positively with PAPP-A and PlGF. The lower the fetal fraction, the higher were the risks for PE < 34 weeks, PE < 37 weeks and FGR < 37 weeks (P < 0.001 for all).

CONCLUSIONS

There is a significant association between fetal fraction result and first-trimester markers for adverse pregnancy outcome. Low fetal fraction is associated with an increased risk for pregnancy complication, but its capacity to act an as independent first-trimester marker in an algorithm for screening for PE and FGR requires further research. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

[Emergency lung ultrasound]

Acute and emergency physicians need to make rapid and far-reaching decisions on the basis of little diagnostic information. In patients with symptoms suggestive of a cardiopulmonary diagnosis, point-of-care lung ultrasound (LUS) is becoming increasingly used. In patients with acute dyspnea, chest pain and shock, LUS increases the diagnostic reliability. The BLUE protocol helps to differentiate important diagnoses of acute dyspnea (pulmonary edema, pneumonia, acute respiratory distress syndrome, pulmonary embolism, pleural effusions or pneumothorax). LUS is also used for treatment follow-up. It is clearly superior to other diagnostic measures (auscultation, chest X‑ray). With ever smaller "handheld" ultrasound devices, the use of ultrasound is also being increasingly used in preclinical situations.

Global lower limb muscle coactivation during walking at different speeds: Relationship between spatio-temporal, kinematic, kinetic, and energetic parameters

Muscle coactivation is the mechanism that regulates the simultaneous activity of antagonist muscles around the same joint. During walking, muscle joint coactivation varies within the gait cycle according to the functional role of the lower limb joints. In the present study, we used a time-varying multi-muscle coactivation function (TMCf) with the aim of investigating the coactivation of 12 lower limb muscles and its relationship with the gait cycle, gait speed (low, self-selected, and fast), ground reaction force, gait variability, and mechanical energy consumption, and recovery in a sample of 20 healthy subjects. Results show that the TMCf is speed dependent and highly repeatable within and between subjects, similar to the vertical force profile, and negatively correlated with energy recovery and positively correlated with both energy consumption and balance-related gait parameters. These findings suggest that the global lower limb coactivation behavior could be a useful measure of the motor control strategy, limb stiffness, postural stability, energy efficiency optimization, and several aspects in pathological conditions.

Linkage disequilibrium pattern and genome-wide association mapping for meat traits in multiple porcine F2 crosses

In the present study, data from four F2 crosses were analysed and used to study the linkage disequilibrium (LD) structure within and across the crosses. Genome-wide association analyses (GWASes) for conductivity and dressing out meat traits were conducted using single-marker and Bayesian multi-marker models using the pooled data from all F2 crosses. Porcine F2 crosses generated from the distantly related founder breeds Wild Boar, Piétrain and Meishan, as well as from a porcine F2 cross from the closely related founder breed Piétrain and an F1 Large White × Landrace cross were pooled. A total of 2572 F2 animals were genotyped using a 62K SNP chip. The positions of the SNPs were based on genome assembly Sscrofa11.1. After post-alignment and genotype filtering, approximately 50K SNPs were usable for LD studies and GWASes. The main findings of the present study are that the breakdown of LD was faster in crosses from closely related founder breeds compared to crosses from distantly related founders. The fastest breakdown of LD was observed by pooling the data. Based on the single-marker results and LD structure, clusters and windows were built for 1-Mb intervals. For conductivity and dressing out, 183 and 191 nominal significant associations respectively and six and five clusters respectively were found. Dominance was important for conductivity, and considering dominance in GWASes improved the mapping signals. Most clear signals were found for conductivity on SSC6, 8 and 15 and for dressing out on SSC2 and 7. Considering dominance might contribute to the accuracy of genomic selection and serve as a guide for choosing mating pairs with good combining abilities. However, further research is needed to investigate if dominance is also important in crossbreed pig breeding schemes.

Accuracy and reproducibility of fetal-fraction measurement using relative quantitation at polymorphic loci with microarray

OBJECTIVES

Various methods of fetal-fraction measurement have been employed in conjunction with different approaches to cell-free DNA testing for fetal aneuploidy. In this study, we determined the accuracy and reproducibility of fetal-fraction measurement using polymorphic assays that are incorporated into the test design as part of the Harmony® prenatal test and evaluated whether the single nucleotide polymorphisms selected for and used in these assays can be applied broadly to all patient populations.

METHODS

Clinical maternal plasma samples were assayed using a custom microarray with Digital ANalysis of Selected Regions (DANSR) assays designed to cover non-polymorphic targets on chromosomes of interest for aneuploidy assessment (13, 18, 21, X and Y) and polymorphic targets for fetal-fraction assessment. In a consecutive series of 47 512 maternal plasma samples, fetal-fraction measurements based on polymorphic assays were compared with those from Y-sequence quantitation. Reproducibility was examined between first- and second-tube measurements for the same patient sample in 734 cases. The fraction of informative loci was calculated for 13 988 samples.

RESULTS

There was a strong correlation between fetal fractions determined using the polymorphic assays and using Y-chromosome sequence quantitation (r = 0.97). Fetal-fraction measurement between the first and second tubes was highly reproducible (r = 0.98). The fraction of informative loci observed in a clinical series was consistent with predictions based on assay design.

CONCLUSIONS

The method based on relative quantitation at polymorphic loci on a microarray is accurate and reproducible for fetal-fraction estimation and is equally informative across global populations. This study provides a useful benchmark for ensuring the reliability and accuracy of fetal-fraction measurement. © 2018 Roche Sequencing Solutions. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

First-trimester risk assessment based on ultrasound and cell-free DNA vs combined screening: a randomized controlled trial

OBJECTIVE

This was a randomized controlled trial to compare risk assessment by first-trimester combined screening (FTCS) with an approach that combines a detailed ultrasound examination at 11-13 weeks' gestation and cell-free DNA (cfDNA) analysis.

METHODS

Pregnant women with a normal first-trimester ultrasound examination at 11-13 weeks' gestation (fetal nuchal translucency (NT) ≤ 3.5 mm and no fetal defects) were randomized into one of two groups. In the first group, risk of aneuploidy was assessed using FTCS based on the most recent UK Fetal Medicine Foundation algorithm. In the second group, risk assessment was based on ultrasound findings and cfDNA analysis. An additional tube of blood was collected for FTCS in case the cfDNA analysis was uninformative. Primary outcome was false-positive rate in screening for trisomy 21. A case was considered false positive if the karyotype was not trisomy 21 and if the risk for trisomy 21 was >1:100, irrespective of the method of risk calculation. Results were compared using 95% CIs using the Clopper-Pearson method.

RESULTS

Between October 2015 and December 2016, 1518 women with singleton pregnancy underwent first-trimester screening. Thirty-one (2.0%) pregnancies were not eligible for randomization due to increased NT (> 3.5 mm) and/or fetal defect. After exclusion of women who declined randomization (n = 87) and cases of fetal death and loss to follow-up (n = 24), 688 pregnancies were randomized into the FTCS arm and 688 into the ultrasound + cfDNA analysis arm. There were no differences in maternal and gestational age, maternal weight and BMI, ethnicity, use of assisted reproduction and cigarette smoking between the two arms. In the ultrasound + cfDNA analysis arm, median risk for trisomy 21 was 1 in 10 000. None of the cases had a risk above 1: 100 (95% CI, 0.0-0.5%). In the FTCS arm, the median risk for trisomy 21 was 1 in 3787 and in 17 cases, the risk was higher than 1:100, which corresponds to 2.5% (95% CI, 1.5-3.9%) of the FTCS study-arm population.

CONCLUSION

Our study has shown that first-trimester risk assessment for trisomy 21 that includes a detailed ultrasound examination as well as NT measurement and is followed by cfDNA testing is associated with a significant reduction in the false-positive rate compared with FTCS. This approach obviates the need for maternal serum free β-human chorionic gonadotropin and pregnancy-associated plasma protein-A in screening for fetal aneuploidy. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Common surgical procedures in pilonidal sinus disease: A meta-analysis, merged data analysis, and comprehensive study on recurrence

We systematically searched available databases. We reviewed 6,143 studies published from 1833 to 2017. Reports in English, French, German, Italian, and Spanish were considered, as were publications in other languages if definitive treatment and recurrence at specific follow-up times were described in an English abstract. We assessed data in the manner of a meta-analysis of RCTs; further we assessed non-RCTs in the manner of a merged data analysis. In the RCT analysis including 11,730 patients, Limberg & Dufourmentel operations were associated with low recurrence of 0.6% (95%CI 0.3-0.9%) 12 months and 1.8% (95%CI 1.1-2.4%) respectively 24 months postoperatively. Analysing 89,583 patients from RCTs and non-RCTs, the Karydakis & Bascom approaches were associated with recurrence of only 0.2% (95%CI 0.1-0.3%) 12 months and 0.6% (95%CI 0.5-0.8%) 24 months postoperatively. Primary midline closure exhibited long-term recurrence up to 67.9% (95%CI 53.3-82.4%) 240 months post-surgery. For most procedures, only a few RCTs without long term follow up data exist, but substitute data from numerous non-RCTs are available. Recurrence in PSD is highly dependent on surgical procedure and by follow-up time; both must be considered when drawing conclusions regarding the efficacy of a procedure.

Hypersexualität unter Aripiprazol

Sexuelle Funktionsstörungen bei an Schizophrenie leidenden Patienten finden trotz hoher Prävalenz in der klinischen Praxis weiterhin wenig Beachtung. Meist führt eine Antipsychotika-induzierte Hyperprolaktinämie zu verminderter Libido oder anderen sexuellen Funktionsstörungen.Wir berichten den Fall einer 42-jährigen an einer schizoaffektiven Störung leidenden Patientin, bei der es unter Aripiprazol zu vermehrter sexueller Appetenz und Libido gekommen ist. Neben einem fehlenden Einfluss auf das Prolaktinsystem, welches vermutlich die Antipsychotika-induzierte sexuelle Dysfunktion bedingt, kann angenommen werden, dass Aripiprazol das mesolimbische Dopaminsystem über einen partialagonistischen D2-Rezeptoreffekt stimuliert und zu einer vermehrten sexuellen Appetenz führt. Dieser stimulierende Effekt könnte bei Antipsychotika-induzierten sexuellen Funktionsstörungen genutzt werden. Jedoch sollten Symptome wie Hypersexualität oder vermehrte sexuelle Appetenz unter Aripiprazol explizit erfragt werden.

Emotionsregulation und zwischenmenschliche Beziehungen bei Jugendlichen mit NSSV

Charakteristisch für Jugendliche mit nicht suizidalem selbstverletzendem Verhalten (NSSV) sind Emotionsregulationsschwierigkeiten. Schwierigkeiten in zwischenmenschlichen Beziehungen sind direkt und indirekt über eine inadäquate Emotionsregulation mit NSSV assoziiert. Wichtige Aspekte einer gelungenen Emotionsregulation und funktionierenden zwischenmenschlichen Beziehungen sind die Emotionserkennung und der Emotionsausdruck. Studien mit Patienten mit einer Borderline-Persönlichkeitsstörung, die oft NSSV zeigen, weisen auf Auffälligkeiten in der Emotionserkennung hin. Zudem gibt es erste Ergebnisse in Richtung eines verminderten Emotionsausdrucks bei dieser Patientengruppe. In der Therapie von Jugendlichen mit NSSV ist die Förderung von Emotionsregulationskompetenzen und sozialen Fertigkeiten wichtig. Möglicherweise könnten Übungen zur Emotionserkennung und zum adäquaten Emotionsausdruck bestehende Therapiekonzepte ergänzen.

Extending Statistical Boosting

Background: Boosting algorithms to simultaneously estimate and select predictor effects in statistical models have gained substantial interest during the last decade.

Objectives: This review highlights recent methodological developments regarding boosting algorithms for statistical modelling especially focusing on topics relevant for biomedical research.

Methods: We suggest a unified framework for gradient boosting and likelihood-based boosting (statistical boosting) which have been addressed separately in the literature up to now.

Results: The methodological developments on statistical boosting during the last ten years can be grouped into three different lines of research: i) efforts to ensure variable selection leading to sparser models, ii) developments regarding different types of predictor effects and how to choose them, iii) approaches to extend the statistical boosting framework to new regression settings.

Conclusions: Statistical boosting algorithms have been adapted to carry out unbiased variable selection and automated model choice during the fitting process and can nowadays be applied in almost any regression setting in combination with a large amount of different types of predictor effects.

The relationships between gender, psychopathic traits and self-reported delinquency: a comparison between a general population sample and a high-risk sample for juvenile delinquency

BACKGROUND

Studies have shown that youths with high psychopathic traits have an earlier onset of delinquent behavior, have higher levels of delinquent behavior, and show higher rates of recidivism than youths with low psychopathic traits. Furthermore, psychopathic traits have received much attention as a robust indicator for delinquent and aggressive behavior in both boys and girls. However, there is a notable lack of research on gender differences in the relationship between psychopathic traits and delinquent behavior. In addition, most of the studies on psychopathic traits and delinquent behavior were conducted in high-risk samples. Therefore, the first objective of the current study was to investigate the relationship between psychopathic traits and specific forms of self-reported delinquency in a high-risk sample for juvenile delinquency as well as in a general population sample. The second objective was to examine the influence of gender on this relationship. Finally, we investigated whether the moderating effect of gender was comparable in the high-risk sample for juvenile delinquency and the general population sample.

METHODS

Participants were 1220 adolescents of the German-speaking part of Switzerland (N = 351 high-risk sample, N = 869 general population sample) who were between 13 and 21 years of age. The Youth Psychopathic traits Inventory (YPI) was used to assess psychopathic traits. To assess the lifetime prevalence of the adolescents' delinquent behavior, 15 items derived from a self-report delinquency instrument were used. Logistic regression analyses were used to examine the relationship between gender, psychopathic traits and self-reported delinquency across both samples.

RESULTS

Our results demonstrated that psychopathic traits are related to non-violent and violent offenses. We found no moderating effect of gender and therefore we could not detect differences in the moderating effect of gender between the samples. However, there was a moderating effect of sample for the relationship between the callous and unemotional YPI scale and non-violent offenses. In addition, the regression weights of gender and sample were, for non-violent offenses, reduced to non-significance when adding the interaction terms.

CONCLUSIONS

Psychopathic traits were found to be present in a wide range of youths (i.e., high-risk as well as general population sample, young children as well as adolescents, boys as well as girls) and were related to delinquent behavior. The influence of age and YPI scales on self-reported delinquency was more robust than the influence of gender and sample. Therefore, screening for psychopathic traits among young children with psychosocial adjustment problems seems relevant for developing effective intervention strategies.

The role of phenotypic plasticity on population differentiation

Several evolutionary processes shape the genetic and phenotypic differentiation of populations. Among them, the joint effects of gene flow, selection and phenotypic plasticity are poorly known, especially when trying to understand how maladaptive plasticity affects population divergence. We extended a quantitative genetic model of Hendry et al. (2001) to describe these joint effects on phenotypic and additive genetic divergence between two populations, and their phenotypic and genetic differentiation (PST and QST). With individual-based simulations, we tested our model predictions and further modeled allelic differentiation at neutral (FST) and adaptive (FSTQ) loci. While adaptive phenotypic plasticity allows for large phenotypic divergence and differentiation despite high gene flow, maladaptive plasticity promotes genetic divergence and generates countergradient variation, under extensive migration with phenotypic differences sometimes opposed to genetic differences. Maladaptive plasticity can also promote adaptive phenotypic divergence by reducing the effective gene flow. Overall, plasticity decouples genetic from phenotypic differences between populations, and blurs the correlation between phenotypic divergence and local adaptation. By deriving models of population differentiation for three different life cycles, we further describe the effect of a species' ecology on evolution in structured populations.