Sulfate is covalently linked to the oligosaccharides on the alpha and beta subunits of bovine lutropin (luteinizing hormone; LH) but not to those on human chorionic gonadotropin (hCG). Since the amino acid sequences of the pituitary and placental alpha subunits are homologous, comparison of their asparagine-linked sugars can provide information regarding tissue specificity of oligosaccharide ma...

OBJECTIVE To estimate the difference between levels of the two biochemical markers pregnancy-associated plasma protein-A (PAPP-A) and maternal serum free β-human chorionic gonadotropin (free β-hCG) in twin pregnancies relative to singleton pregnancies and establish an improved screening procedure for chromosomal abnormalities such as trisomy 21 in twin pregnancies. METHODS 4843 unaffected and...

OBJECTIVE To examine the levels of free beta-human chorionic gonadotrophin (free beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) in second-trimester maternal serum from pregnancies affected by trisomy 13 and compare these with the known reduced levels of these markers in first-trimester cases in an attempt to better understand the pathophysiology of changes in marker levels in chro...

OBJECTIVE To examine the distribution of first-trimester biochemical markers of aneuploidy in twin pregnancies, and to assess whether there are differences in the distributions between monochorionic and dichorionic twins. METHODS Maternal serum-free beta-hCG and PAPP-A were measured between 11 + 0 and 13 + 6 weeks as part of a routine first-trimester screening program in conjunction with feta...

OBJECTIVE Firstly, to establish a reference range of birth weight with gestation at delivery; secondly, to identify maternal characteristics that are significantly associated with birth weight; and thirdly, to determine if combinations of maternal characteristics, fetal nuchal translucency thickness (NT), and serum concentrations of free beta-human chorionic gonadotrophin (β-hCG) and pregnancy-...

The study tested the hypothesis that human chorionic gonadotrophin (hCG) attenuates isolated vascular smooth muscle contractility and investigated the role of the vascular endothelium in hCG-induced altered responses of vascular smooth muscle. The contractile responses of isolated aortic rings from normal, hCG-treated, and estrogen-treated female virgin Wistar rats to phenylephrine, angiotensin...

OBJECTIVE To examine the performance of screening for trisomies 21, 18 and 13 at 11-13 weeks' gestation using specific algorithms for these trisomies based on combinations of fetal nuchal translucency thickness (NT), fetal heart rate (FHR), ductus venosus pulsatility index for veins (DV PIV), and serum free β-human chorionic gonadotropin (β-hCG), pregnancy-associated plasma protein A (PAPP-A), ...

The isolated cell membranes from bovine corpora lutea bound lz51-human chorionic gonadotropin (HCG) with high affinity and specificity. The specific binding was saturable with respect to the amounts of membrane protein and 12jIHCG added. Approximately 8.4 x 10-l” M 124-HCG saturated all the receptor sites in 1.0 mg of membrane protein. The specific binding of 12sI-HCG was strong and not readily...

OBJECTIVE To assess the suitability of either the log-linear or reciprocal-linear regression procedure for maternal weight correction of biochemical marker MoMs in the first trimester. METHODS Data from two prospective first-trimester OSCAR screening programmes including 32,010 women with first-trimester maternal serum-free beta-hCG and PAPP-A measured by the Kryptor analyser was analysed by ...

48075, in which the 2nd International Standard for HCG is used. This colorimetric method is ideally suited for the small laboratory because of its simplicity and minimal equipment requirements. Essentially, the test is a solid-phase IEM involving pelystyrene tubes coated with anti-HCG (monoclonal mouse IgG). The serum HCG is “sandwiched” (1) by the solid-phase HCG enzymelabeled antibody at room...