Sexual disparity of copeptin in healthy newborn infants.

BACKGROUND: Arginine vasopressin (AVP) regulates water balance and blood pressure and plays a role in social behavioral processes. Healthy adult men as compared with women have higher blood levels of AVP and its C-terminal precursor peptide, copeptin. OBJECTIVE: The objective of the study was to investigate whether sexual disparity of copeptin is present at birth. METHODS: In 241 prospectively enrolled healthy newborn infants, 131 boys and 110 girls, plasma copeptin concentrations were measured at birth and on day 3 of life. RESULTS: Multivariable linear regression analysis revealed stressful delivery (regression coefficient ß = .569, P <0.001), acidosis (ß = -.347, P < .001), and male gender (ß = .132, P < .01) as independent determinants of copeptin at birth. In infants born without stress, that is by primary cesarean section (n = 81), male gender was the sole variable associated with copeptin (ß = .286, P < .05), copeptin concentrations being higher in boys [median 5.5 pmol/L (interquartile range 4.4-10.2)] than in girls [4.8 pmol/L (interquartile range 3.6-5.8), P < .05]. At day 3 of life, copeptin was determined independently by postnatal physiological dehydration (ß = .485; P < .001) and birth weight (ß = .279; P < .01). CONCLUSION: Sexual disparity of copeptin is already present at birth, indicating increased activation of the AVP system in newborn boys as compared with girls.

Cardiovascular biomarkers in preeclampsia at triage.

INTRODUCTION: To investigate the ability of cardiovascular plasma biomarkers to identify imminent preeclampsia (PE) among pregnant women at triage. MATERIAL AND METHODS: C-terminal pro-arginine vasopressin (copeptin), C-terminal pro-endothelin-1 (CT-proET-1), mid-regional pro-adrenomedullin (MR-proADM), and mid-regional pro-atrial natriuretic peptide (MR-proANP) were prospectively measured in pregnant women presenting at the obstetrical triage units of the University Hospitals of Basel and Zurich, Switzerland. Logistic regression and receiver operating characteristics (ROC) analysis was used to assess and quantify the predictive ability of cardiovascular biomarkers. RESULTS: Of the 147 included women, 27 (18.4%) were diagnosed at admission with PE. All biomarker levels were significantly higher in participants with PE as compared to controls. However, only MR-proANP, MR-proADM and CT-proET-1 were significant and independent predictors of PE, after taking into account the effect of various clinical confounders. The area under the ROC curve (AUC) was 0.62 (95% confidence interval 0.50-0.73) for copeptin, 0.64 (0.52-0.76) for MR-proADM, 0.71 (0.61-0.82) for CT-proET-1, and 0.83 (0.73-0.92) for MR-proANP. The combination of MR-proANP and MR-proADM resulted in the highest diagnostic performance (AUC 0.88; 0.79-0.96). DISCUSSION: Assessment of the cardiovascular plasma biomarkers MR-proANP and MR-proADM holds promise to support diagnosis of PE at triage.

Plasma midregional proadrenomedullin in newborn infants: impact of prematurity and perinatal infection.

INTRODUCTION: Adrenomedullin (ADM) is one of the strongest endogenous vasodilating hormones. Its stable by-product midregional-proADM (MR-proADM) is an established indicator of systemic infection and cardiovascular compromise in adult patients. METHODS: A prospective cross-sectional study was performed to investigate the perinatal factors affecting MR-proADM plasma concentrations in 328 newborn infants with a gestational age (GA) between 24 and 41 wk. RESULTS: Blood samples were obtained in 270 infants from umbilical veins (with additional 108 paired samples from umbilical arteries), and at 2-3 d of life in 183 infants. Paired venous and arterial umbilical cord MR-proADM concentrations were closely related (Spearman's rank order correlation coefficient (R(s)) = 0.825, P < 0.001). MR-proADM concentrations at birth and at 2-3 d were inversely related to GA (R(s) = -0.403 and R(s) = -0.541, respectively) and birth weight (BW; R(s) = -0.421 and R(s) = -0.530, respectively; all P < 0.001). On stepwise regression analysis, clinical chorioamnionitis and umbilical arterial blood base excess retained a significant impact on MR-proADM cord venous blood concentrations. At 2-3 d of life, histologic chorioamnionitis and GA at delivery were significantly associated with MR-proADM levels. DISCUSSION: As compared with adults, MR-proADM concentrations are elevated in neonates, especially those born very preterm. Immaturity and infection, which both feature low systemic vascular resistance, are related to increased MR-proADM concentrations.

High resolution array in the clinical approach to chromosomal phenotypes.

Array genomic hybridization (AGH) has recently been implemented as a diagnostic tool for the detection of submicroscopic copy number variants (CNVs) in patients with developmental disorders. However, there is no consensus regarding the choice of the platform, the minimal resolution needed and systematic interpretation of CNVs. We report our experience in the clinical diagnostic use of high resolution AGH up to 100 kb on 131 patients with chromosomal phenotypes but previously normal karyotype. We evaluated the usefulness in our clinics and laboratories by the detection rate of causal CNVs and CNVs of unknown clinical significance and to what extent their interpretation would challenge the systematic use of high-resolution arrays in clinical application. Prioritizing phenotype-genotype correlation in our interpretation strategy to criteria previously described, we identified 33 (25.2%) potentially pathogenic aberrations. 16 aberrations were confirmed pathogenic (16.4% syndromic, 8.5% non-syndromic patients); 9 were new and individual aberrations, 3 of them were pathogenic although inherited and one is as small as approx 200 kb. 13 of 16 further CNVs of unknown significance were classified likely benign, for 3 the significance remained unclear. High resolution array allows the detection of up to 12.2% of pathogenic aberrations in a diagnostic clinical setting. Although the majority of aberrations are larger, the detection of small causal aberrations may be relevant for family counseling. The number of remaining unclear CNVs is limited. Careful phenotype-genotype correlations of the individual CNVs and clinical features are challenging but remain a hallmark for CNV interpretation.

Plasma C-terminal pro-endothelin-1 and the natriuretic pro-peptides NT-proBNP and MR-proANP in very preterm infants with patent ductus arteriosus.

BACKGROUND: In very preterm infants, clinical decision-making, such as closing a patent ductus arteriosus (PDA), may be aided by measuring circulating natriuretic and endothelial pro-peptides. OBJECTIVES: To investigate the association between perinatal characteristics, PDA echocardiography and plasma concentrations of stable pro-peptides of B-type natriuretic peptide (NT-proBNP), atrial natriuretic peptide (MR-proANP) and endothelin-1 (CT-proET-1). METHODS: A prospective, cross-sectional, single-center study was performed in 66 infants who were less than 32 weeks of gestational age. Pro-peptide concentrations were determined at birth and at day 2-3 of life. RESULTS: Plasma concentrations of all 3 pro-peptides increased on average 2- to 5-fold from birth to day 2-3 of life. NT-proBNP and MR-proANP were closely related at birth and at day 2-3 (Rs 0.902 and 0.897, respectively, p < 0.001), whereas CT-proET-1 was related to NT-proBNP and MR-proANP at birth (Rs 0.478 and 0.460, respectively, p < 0.001) but not at day 2-3. Birth weight was negatively related to all 3 pro-peptides at birth (p < 0.01); however, preeclampsia and compromised placental perfusion were associated with elevated NT-proBNP and MR-proANP concentrations at birth. At day 2-3, MR-proANP and NT-proBNP correlated significantly with the ductal diameter (Rs 0.416 and 0.415, respectively, both p = 0.011), whereas CT-proET-1 correlated with the left atrium/aorta ratio (Rs 0.506, p = 0.027). CT-proET-1 was elevated in infants with treated compared to untreated PDA [median (5-95% range) 388 (272-723) vs. 303 (152-422) pmol/l, p = 0.011], but not NT-proBNP or MR-proANP. CONCLUSION: CT-proET-1 is a promising predictor in determining the need for PDA intervention.

Plasma pro-endothelin-1 and respiratory distress in newborn infants.

Plasma concentrations of the stable endothelin-1 precursor, C-terminal portion of the endothelin-1 precursor, determined prospectively in 293 newborn infants (gestational age, 24-41 weeks) at birth and on day 3 of life were unrelated to gestational age at birth, but strongly associated with respiratory distress when measured on day 3 of life.

Plasma copeptin in preterm infants: a highly sensitive marker of fetal and neonatal stress.

CONTEXT: Copeptin is a stable by-product of arginine-vasopressin synthesis and reflects its secretion by the pituitary. OBJECTIVE: The objective of the study was to investigate perinatal factors affecting copeptin concentrations in preterm infants at birth and at 3 d of life. DESIGN AND SETTING: This was a prospective cross-sectional study at two Swiss university hospitals. PATIENTS: One hundred sixty-seven preterm infants were enrolled, 59 infants born between 24 and 31 wk gestational age, 50 infants between 32 and 34 wk, and 58 between 35 and 36 wk. MAIN OUTCOME MEASURE: Plasma copeptin concentrations, determined by a CT-proAVP-luminescence-immunoassay, were measured. RESULTS: Copeptin at birth was significantly higher in preterm infants born vaginally [median (range) 366 (1-2900) pmol/liter, n = 43] than those born by cesarean section [6.9 (2-1580), n = 124]. In infants born after cesarean without prior labor (n = 66), estimated fetal weight less than the fifth percentile, suspect fetal heart rate, compromised placental perfusion, and chorioamnionitis were each associated with significantly elevated cord copeptin. Copeptin at 3 d of life was not associated with cord blood copeptin but inversely related to gestational age (Rs = -0.6, P < 0.001) and birth weight (Rs -0.612, P < 0.001). Day 3 copeptin increased alongside the level of mechanical respiratory support. CONCLUSION: Copeptin is a highly sensitive marker of perinatal stress.

High copeptin concentrations in umbilical cord blood after vaginal delivery and birth acidosis.

CONTEXT: The pituitary-secreted nonapeptide arginine-vasopressin (AVP) is unstable and therefore unsuited for diagnostic use, but its secretion can be estimated by measuring copeptin, the C-terminal portion of the AVP precursor (pro-AVP). OBJECTIVE: Our objective was to investigate perinatal factors affecting copeptin concentrations in infants at birth and at 3 d of life. DESIGN AND SETTING: We conducted a prospective cross-sectional study at a tertiary university hospital. PATIENTS: Copeptin plasma concentrations were evaluated in 177 infants at birth, including 117 paired arterial/venous umbilical cord and 102 venous blood samples obtained at 3 d of life. MAIN OUTCOME MEASURE: Copeptin concentrations were determined by a C-terminal pro-AVP luminescence immunoassay. RESULTS: Arterial umbilical cord copeptin concentrations were consistently higher than matched venous ones (median 18 vs. 10 pmol/liter, P < 0.001), but both values were closely related (R(s) = 0.825; P < 0.001), and both were negatively related to arterial umbilical cord pH (R(s) arterial/venous = -0.578/-0.639; P < 0.001). Although exceedingly high copeptin concentrations were observed after vaginal birth in umbilical cord arterial [median (5-95% range) = 1610 (85-5000) pmol/liter] and venous [793 (6-4836) pmol/liter] plasma, copeptin concentrations were low after primary cesarean section [arterial/venous = 8 (3-907)/5 (5-504) pmol/liter]. Postnatal body weight loss was associated with increased copeptin concentrations at d 3 (R(s) = 0.438; P < 0.001) and was inversely related to copeptin concentrations at birth (R(s) = -0.289 and -0.309; both P = 0.001). CONCLUSION: Vaginal birth is associated with a large release of copeptin that exceeds all values published so far, including those in critically ill adult patients with shock or brain injury. Thus, vaginal birth is arguably the most intense stressor in life.

Novel interaction partners of the TPR/MET tyrosine kinase.

A large variety of biological processes is mediated by stimulation of the receptor tyrosine kinase MET. Screening a mouse embryo cDNA library, we were able to identify several novel, putative intracellular TPR/MET-substrates: SNAPIN, DCOHM, VAV-1, Sorting nexin 2, Death associated protein kinase 3, SMC-1, Centromeric protein C, and hTID-1. Interactions as identified by yeast two-hybrid analysis were validated in vitro and in vivo by mammalian two-hybrid studies, a far-western assay and coimmunoprecipitation. Participation in apoptosis-regulating mechanisms through interaction with DAPK-3 and cell cycle control via binding to nuclear proteins such as CENPC and SMC-1 are possible new aspects of intracellular MET signaling.