Cohort profile: Improved Pregnancy Outcomes via Early Detection (IMPROvED), an International Multicentre Prospective Cohort.

Background: Improved Pregnancy Outcomes via Early Detection (IMPROvED) is a multi-centre, European phase IIa clinical study. The primary aim of IMPROvED is to enable the assessment and refinement of innovative prototype preeclampsia risk assessment tests based on emerging biomarker technologies. Here we describe IMPROvED's profile and invite researchers to collaborate.

Preterm preeclampsia screening using biomarkers: combining phenotypic classifiers into robust prediction models.

Background: Preeclampsia screening is a critical component of antenatal care worldwide. Currently, the most developed screening test for preeclampsia at 11 to 13 weeks' gestation integrates maternal demographic characteristics and medical history with 3 biomarkers-serum placental growth factor, mean arterial pressure, and uterine artery pulsatility index-to identify approximately 75% of women who develop preterm preeclampsia with delivery before 37 weeks of gestation. It is generally accepted that further improvements to preeclampsia screening require the use of additional biomarkers.

Relationship between the concentration of ergothioneine in plasma and the likelihood of developing pre-eclampsia.

Ergothioneine, an antioxidant nutraceutical mainly at present derived from the dietary intake of mushrooms, has been suggested as a preventive for pre-eclampsia (PE). We analysed early pregnancy samples from a cohort of 432 first time mothers as part of the Screening for Endpoints in Pregnancy (SCOPE, European branch) project to determine the concentration of ergothioneine in their plasma. There was a weak association between the ergothioneine levels and maternal age but none for BMI.

First-trimester preterm preeclampsia prediction with metabolite biomarkers: differential prediction according to maternal body mass index.

Background: Prediction of preeclampsia risk is key to informing effective maternal care. Current screening for preeclampsia at 11 to 13 weeks of gestation using maternal demographic characteristics and medical history with measurements of mean arterial pressure, uterine artery pulsatility index, and serum placental growth factor can identify approximately 75% of women who develop preterm preeclampsia with delivery at <37 weeks of gestation. Further improvements to preeclampsia screening tests will likely require integrating additional biomarkers.

Early cost-effectiveness analysis of screening for preeclampsia in nulliparous women: A modelling approach in European high-income settings.

Background: Preeclampsia causes substantial maternal and perinatal morbidity and mortality and significant societal economic impact. Effective screening would facilitate timely and appropriate prevention and management of preeclampsia.

Objectives: To develop an early cost-effectiveness analysis to assess both costs and health outcomes of a new screening test for preeclampsia from a healthcare payer perspective, in the United Kingdom (UK), Ireland, the Netherlands and Sweden.

Revealing of endogenous Marinobufagin by an ultra-specific and sensitive UHPLC-MS/MS assay in pregnant women.

Marinobufagenin (MBG) is a bufadienolide cardiac inotrope implicated in volume expansion-mediated hypertensive states including essential hypertension and preeclampsia (PE). Endogenous MBG is an inhibitor of the α1-isoform of Na,K-ATPase with vasoconstrictive and cardiotonic properties, causing hypertension and natriuresis. Elevated endogenous MBG-like material levels have been described by immunoassays in salt-sensitive pregnant and preeclamptic rats as well as in preeclamptic human patients.

A novel method for interrogating receiver operating characteristic curves for assessing prognostic tests.

Background: Disease prevalence is rarely explicitly considered in the early stages of the development of novel prognostic tests. Rather, researchers use the area under the receiver operating characteristic (AUROC) as the key metric to gauge and report predictive performance ability. Because this statistic does not account for disease prevalence, proposed tests may not appropriately address clinical requirements.

Mid-trimester maternal ADAM12 levels differ according to fetal gender in pregnancies complicated by preeclampsia.

An overrepresentation of adverse pregnancy outcomes has been observed in pregnancies associated with a male fetus. We investigated the association between fetal gender and candidate biomarkers for preeclampsia. Proteins were quantified in samples taken at 20 weeks from women recruited to the SCreening fOr Pregnancy Endpoints (SCOPE) study (preeclampsia n = 150; no preeclampsia n = 450).

Integrated proteomics pipeline yields novel biomarkers for predicting preeclampsia.

Preeclampsia, a hypertensive pregnancy complication, is largely unpredictable in healthy nulliparous pregnant women. Accurate preeclampsia prediction in this population would transform antenatal care. To identify novel protein markers relevant to the prediction of preeclampsia, a 3-step mass spectrometric work flow was applied.

OS043. Identification and validation of novel markers for the predictionof pre-eclampsia.

Introduction: Currently no test accurately predicts pre-eclampsia (PE) in a healthy nulliparous population. Unbiased protein biomarker discovery has the potential to identify novel markers but multimarker panels are required to achieve clinically relevant prediction of PE. To this purpose, single biomarker performances were obtained and multimarker panels developed in a significant subcohort of the international Screening fOr Pregnancy Endpoints study (SCOPE) study [1].

Unbiased plasma proteomics for novel diagnostic biomarkers in cardiovascular disease: identification of quiescin Q6 as a candidate biomarker of acutely decompensated heart failure.

Aims: Biochemical marker testing has improved the evaluation and management of patients with cardiovascular diseases over the past decade. Natriuretic peptides (NPs), used in clinical practice to assess cardiac dysfunction, exhibit many limitations, however. We used an unbiased proteomics approach for the discovery of novel diagnostic plasma biomarkers of heart failure (HF).

Toward clinical proteomics on a next-generation sequencing platform.

We report the first next generation sequencing (NGS) application to identify and quantify proteins. Customization of protein specific aptamers enabled direct conversion of serum protein information into NGS read outs. The intrinsic ability of aptamer sequencing to highly multiplex protein detection and quantification, together with the prospect of DNA sequencing further evolving into a commodity technology, could constitute the core of a novel, universal diagnostics paradigm.

Highly efficient peptide separations in proteomics. Part 2: bi- and multidimensional liquid-based separation techniques.

Multidimensional liquid-based separation techniques are described for maximizing the resolution of the enormous number of peptides generated upon tryptic digestion of proteomes, and hence, reduce the spatial and temporal complexity of the sample to a level that allows successful mass spectrometric analysis. This review complements the previous contribution on unidimensional high performance liquid chromatography (HPLC). Both chromatography and electrophoresis will be discussed albeit with reversed-phase HPLC (RPLC) as the final separation dimension prior to MS analysis.

Application of a combined weak cation-exchange/crown ether column: first demonstrations of a versatile tool for proteome subselection.

The present paper introduces the use of a weak cation-exchange/crown ether column in the proteomics field. The 18-crown-6 ether functionality is well-known to selectively complex ammonium and monoalkylammonium ions, which should make this column highly suitable to trap peptides with free alpha-NH(2) or free epsilon-NH(2) groups from lysine side chains. This unique selection mechanism was put to the test in an N-teromics setup which aims for the enrichment of deliberately acetylated protein N-terminal peptides from a serum digest.

Online immobilized metal affinity chromatography/mass spectrometric analysis of changes elicited by cCMP in the murine brain phosphoproteome.

An automated online immobilized metal affinity chromatography/high-performance liquid chromatography mass spectrometric (IMAC-HPLC/MS/MS) method was developed to study cytidine 3',5'-cyclic monophosphate (cCMP)-specific protein phosphorylation, analogous to a previously successful offline IMAC method using microvolume IMAC pipette tips. The optimized method identified murine brain phosphoproteins selectively modified by challenge with cCMP, using manual interpretation of the results to confirm both phosphorylation and selectivity of response to cCMP. A number of proteins identified by this strategy have potential roles in hyperproliferation, a previously reported response to elevated levels of cCMP.

Development of an on-line SPE-LC-ESI-MS method for urinary nucleosides: hyphenation of aprotic boronic acid chromatography with hydrophilic interaction LC-ESI-MS.

The development of an on-line automated SPE-HPLC--ESI-MS method is described for targeted metabolomic analysis of urinary modified nucleoside levels. The setup comprises a boronate affinity column as a trapping device, a hydrophilic interaction chromatography (HILIC) separation and information-dependent MS detection modes. The system was optimized using standards and tested on biological samples, detecting a number of modified nucleosides.

Role of nitrogen lewis basicity in boronate affinity chromatography of nucleosides.

Urinary modified nucleosides have a potential role as cancer biomarkers, and most of the methods used in their study have utilized low-pressure phenylboronate affinity chromatography materials for the purification of the cis-diol-containing nucleosides. In this study, a boronate HPLC column was surprisingly shown not to trap the nucleosides as would be expected from experience with the classic Affigel 601 resin but showed only partial selectivity toward cis-diol groups while other groups exhibited better retention. In aprotic conditions, trapping of nucleosides was possible; however, the selectivity toward cis-diol-containing compounds was lost with the Lewis basicity of available nitrogens being the main determinant of retention.

Mass spectrometric identification of Rab23 phosphorylation as a response to challenge by cytidine 3',5'-cyclic monophosphate in mouse brain.

While the functions and mechanisms of action of adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5'-cyclic monophosphate (cGMP) are well established and are the basis of the action of a large number of successful pharmaceuticals, the role of a third naturally occurring cyclic nucleotide, cytidine 3',5'-cyclic monophosphate (cCMP), remains to be elucidated. Immobilized metal affinity chromatography (IMAC) was used to selectively extract proteins phosphorylated in mouse brain in response to challenge by cAMP, cGMP and cCMP, followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToFMS) and liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) of tryptic digests to identify Rab23 as the first protein reported to be phosphorylated only in response to cCMP.

In-source CID of guanosine: gas phase ion-molecule reactions.

In-source collision induced dissociation was applied to access second generation ions of protonated guanosine. The in-source gas-phase behavior of [BH2]+-NH3 (m/z 135, C5H3N4O+) was investigated. Adduct formation and reactions with available solvent molecules (H2O and CH3OH) were demonstrated.

Stainless steel electrospray probe: a dead end for phosphorylated organic compounds?

A study of the interaction of phosphorylated organic compounds with the stainless components of a liquid chromatography-electrospray ionisation-mass spectrometry system (LC-ESI-MS) was carried out to disclose a (forgotten?) likely pitfall in the LC-ESI-MS analysis of phosphorylated compounds. The retention behaviour of some representative compounds of different important classes of phosphorylated biomolecules such as nucleotides, oligonucleotides, phosphopeptides, phospholipids and phosphorylated sugars was investigated during their passage through the injector and the stainless steel electrospray capillary. It became clear that the stainless steel components within the LC-ESI-MS setup were able to retain and trap phosphorylated compounds when these compounds were introduced under acidic conditions (0.

Analysis of urinary nucleosides. V. Identification of urinary pyrimidine nucleosides by liquid chromatography/electrospray mass spectrometry.

Modified urinary nucleosides are potentially invaluable in cancer diagnosis, as they reflect altered RNA turnovers. High-performance liquid chromatography (HPLC) was combined with full-scan mass spectrometry, tandem mass spectrometry, MS(n) analysis and accurate mass measurements in order to identify pyrimidine nucleosides purified from urine. Potential nucleosides were assessed by their evident UV absorbance in the HPLC chromatogram and then further examined by the various mass spectrometric techniques.