PubMed HealthSearch

Biomedical subjects

Y B Gordon

Publications and source records attributed to Y B Gordon.

36 records · Page 2Linked to original sources

Fetal wastage as a result of an alpha-fetoprotein screening programme.

Amniocentesis was performed in 102 pregnancies in which maternal serum-alpha-fetoprotein (A.F.P.) concentrations were raised. 18 pregnancies were terminated. There were 15 neural-tube defects, 2 gastrointestinal abnormalities (1 of which could have been corrected by surgery), and 1 case of hydrocephaly. There was an association between raised maternal serum-A.F.P. and complications of late pregnancy including premature labour, perinatal death, and severe pre-eclampsia. After amniocentesis there was spontaneous abortion of 3 normal fetuses and 1 abnormal fetus.

Abortion, Spontaneous

Circulating levels of alpha-fetoprotein and pregnancy specific beta1 glycoprotein in pregnancies without an embryo.

Ten patients with depressed serum alpha-fetoprotein (AFP) levels at 14 to 15 weeks gestation were found to have no embryo on ultrasonography: two patients had hydatiform moles and the remainder had anembryonic pregnancies (blighted ova). The pregnancy specific beta1 glycoprotein (SP1) levels in serum were measured in all these ten patients. Seven of the eight patients with anembryonic pregnancies and one of the two patients with molar pregnancies had low serum SP1 levels. These observations suggest that the measurement of AFP and SP1 may provide biochemical evidence of pregnancy without an embryo.

Abortion, Spontaneous

Measurement of ferritin in serum by radioimmunoassay.

A method for the measurement of circulating ferritin concentrations by direct radioimmunoassay is presented. The method described is simple to operate, precise, and sensitive and is suitable for the routine diagnostic measurement of ferritin in either plasma or serum.

Bone Marrow

Pregnancy specific beta1 glycoprotein in fetal and maternal compartments.

Pregnancy specific beta glycoprotein is produced by the syncytiotrophoblast and secreted into the maternal peripheral circulation reaching levels of approximately 200 m/liter in normal pregnancy at term. In the present study the distribution of this newly defined placental protein was examined in maternal and fetal compartments in 12 patients at delivery.

Amniotic Fluid

Characterisation of serum fibrinogen degradation products using gel chromatography and radioimmunoassay.

Fibrin(ogen) degradation products (FDP) are detected by radioimmunoassay in the serum of all subjects. Some of these FDPs have considerable biological activity in vivo, and hence may play a significant part in the process of coagulation. Chromatography of serum samples from patients including those with pulmonary emboli and deep venous thrombosis indicates that the majority of non-clottable fibrin(ogen)-related antigen present is of high molecular weight--greater than that of fibrinogen--and that in pathological situations there is a quantitative increase not a qualitative alteration in the molecular species present.

Chromatography, Gel

Specific and sensitive determination of pregnancy-specific beta 1-glycoprotein by radioimmunoassay. A new pregnancy test.

A specific and highly sensitive radioimmunoassay (R.I.A.) for determination of pregnancy-specific beta 1-glycoprotein (S.P.1) in human plasma, urine, amniotic fluid, and breast milk has been developed. The minimum detection limit of S.P.1 was 8 mug/1 of sample. The assay was applied to plasma and/or urine samples from 8 women in early pregnancy. S.P. 1 was detected in the plasma of all three women obtained within 14 days of ovulation, the earliest positive result being at 7 days. In another woman plasma was negative at day 18 and positive by day 22. In the three remaining women plasma S.P.1 was detected when measured within 24 to 36 days of ovulation. S.P.1 was detected in four urine samples obtained between 20 and 28 days after ovulation. S.P.1 was also measured in breast milk, amniotic fluid, cord blood, and plasma of women with ectopic gestation and trophoblastic disease. It is suggested that the assay of S.P.1 may have important advantages over existing systems for detection and monitoring of early pregnancy.

Amniotic Fluid

Circulating levels of pregnancy-specific beta1-glycoprotein in early pregnancy.

Circulating levels of pregnancy-specific beta1-glycoprotein (SP1 or PSbetaG), luteinizing hormone (LH) and human chorionic gonadotrophin (HCG) were measured serially in 9 subjects immediately after conception. Ovulation occurred spontaneously in 3 subjects, or followed administration of clomiphene citrate (2 subjects) or bromocriptine (4 subjects). The timing of ovulation was determined by the appearance of the LH surge. Levels of HCG were detected 10 to 16 days, and SP1, 18 to 23 days after ovulation. These findings suggest that the measurement of plasma levels of SP1 may provide valuable additional biochemical evidence of pregnancy.

Chorionic Gonadotropin

alpha-Fetoprotein levels in pregnancies complicated by gastrointestinal abnormalities of the fetus.

alpha-Fetoprotein (AFP) levels have been measured in maternal serum and amniotic fluid in a variety of gastrointestinal abnormalities of the fetus. Maternal serum AFP levels were consistently elevated in abdominal wall defects of the fetus after 15 weeks gestation and the amniotic fluid levels were raised in 3 of the 4 patients measured. In atresia of the gastrointestinal tract and diaphragmatic hernia, serum AFP levels were usually normal unless there was an associated neural tube defect or multiple pregnancy, although the majority were not measured between 15 and 26 weeks gestation. If elevated amniotic fluid levels of AFP are used in the decision to terminate pregnancy on the assumption of a probable neural tube defect of the fetus, a proportion of terminations will be performed because of abdominal wall defects of the fetus.

Abdominal Muscles

Screening for fetal neural tube defects by maternal plasma alpha-fetoprotein determination.

A total of 5539 consecutive pregnant patients at three maternity units in the City and Hackney District of London were screened for fetal neural tube defect by measurement of maternal plasma alpha-fetoprotein (AFP) levels. Only 25-7% of women booked at 16 to 22 weeks, the optimum time for this screening test; 54-1% booked before 16 weeks and 20-2% after 22 weeks. Of the women tested before 23 weeks, 300 had elevated levels of AFP in plasma and 14 of them had fetuses with abnormalities known to cause a rise in AFP levels (12 fetuses had a neural tube defect and 2 had alimentary tract abnormalities). Of women examined before 23 weeks, half of those with twin pregnancies had elevated levels of plasma AFP as did 16-7% of those who ultimately had a spontaneous abortion.

Abortion, Spontaneous

Circulating levels of pregnancy-specific beta1-glycoprotein and human placental lactogen in the third trimester of pregnancy: their relationship to parity, birth weight, and placental weight.

Circulating levels of pregnancy-specific beta1-glycoprotein (SP1) and human placental lactogen (HPL) were measured in 153 normal subjects during the third trimester of pregnancy. The levels of SP1 and HPL showed a skewed distribution and rose progressively to reach a plateau by the 36th week. The normal range was calculated by ranking the data and division into centiles as well as by logarithmic transformation of the values. A low but significant correlation was observed between SP1 and HPL levels, SP1 and birth weight. There was also a correlation between HPL levels and placental weight.

Birth Weight

Amniotic fluid levels of fibrin(ogen) degradation fragment E and alpha-fetoprotein in normal pregnancy and with fetal neural tube defect.

Amniotic fluid levels of alpha-fetoprotein (AFP) and fibrin(ogen) degradation fragment E (FgE) were measured in 214 normal subjects and 27 pregnancies associated with an abnormal fetus (open neural tube defect or exomphalos). AFP levels showed no overlap between the normal and abnormal groups, thus confirming the reliability of the AFP assay in the detection of these abnormalities. FgE levels however showed considerable overlap and could not be used as a diagnostic parameter. Agarose gel chromatography of the amniotic fluid revealed the presence of large molecular weight FgE related antigen in open neural tube defect suggesting that leakage of proteins from exposed capillaries is responsible for the elevation of amniotic fluid protein levels.

Amniotic Fluid

Conditions for collection of serum samples for the measurement of fibrin(ogen) degradation products by radioimmunoassay of fragment E.

A number of conditions have been assessed for the collection of serum samples for the measurement of fibrin(ogen) degradation products using a radioimmunoassay for degradation fragment E, which permits precise quantitation of differences. Blood should be collected using minimal venous occlusion into glass tubes containing 10 mg/ml of epsilon amino caproic acid and allowed to clot at 4 to 20 degrees C for at least 4 hours before centrifugation. The serum may be stored at 4 or -20 degrees C. Samples from patients receiving anticoagulant therapy should be treated with 10 IU of thrombin per ml.

Aminocaproates

Levels of alpha-fetoprotein in maternal blood as a screening test for fetal neural-tube defect.

A range has been established for maternal plasma-alpha-fetoprotein (A.F.P.) levels in normal pregnancies (930 women). A.F.P. levels between 10 and 40 weeks gestation were examined in 51 pregnancies associated with fetal neural-tube defect. In 96% of cases (20 anencephalus, 6 spina bifida) examined between 16 and 26 weeks of gestation A.F.P. levels were above the 95th centile of the normal range. It is suggested that measurement of A.F.P. in maternal blood should become a screening test in all pregnancies, and a scheme for the futher investigation of patients with abnormal results is described.

Anencephaly

Serum fibrin(ogen) degradation products in diagnosis of deep-vein thrombosis and pulmonary embolism after hip surgery.

Levels of fibrin(ogen) degradation products (F.D.P.) have been measured by radioimmunoassay for degradation product E (FgE) and by tanned-red-cell haemagglutination-inhibition immunoassay (T.R.C.H.I.I.) in the serum of thirty-three patients undergoing total hip replacement. Levels of F.D.P. did not correlate with thermographic evidence of deep-venous thrombosis. However, in 34 patients with pulmonary embolism, levels of F.D.P. measured by the T.R.C.H.I.I. were transiently raised at the time of embolus, and FgE concentrations were increased for up to 5 days preceding the embolus. Since the measurments of FgE is simple, convenient, and cheap, this estimation might constitute a valuable screening test for major thromboembolic episodes in the postoperative period.

Aged