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Biomedical subjects

B B Saxena

Publications and source records attributed to B B Saxena.

At least 73 records · Page 4Linked to original sources
PubMed1977

Testosterone and dihydrotestosterone in maternal and cord blood and in amniotic fluid.

Maternal and umbillical arterial and venous plasma and amniotic fluid testosterone (T) and dihydrotestosterone (DHT) were measured by radioimmunoassay. Maternal plasma T was 690 +/- 80 pg. per milliliter (mean +/- S.E.) in early pregnancy (less than 20 weeks) and increased significantly (p = 0.0002) to 1,095 +/- 177 pg. per milliliter in late pregnancy (greater than 20 weeks). DHT was 113.0 +/- 18.8 pg. per milliliter in early pregnancy and 179.8 +/- 30.5 pg. per milliliter in late pregnancy. Both umbilical arterial (UA) and umbilical venous (UV) plasma T were significantly higher in 11 male infants (UA T = 135.6 +/- 16.5 pg. per milliliter; UV T = 227.5 +/- 40.8 pg. per milliliter) than in 12 female infants (UA T = 92.1 +/- 9.7 pg. per milliliter; UV T = 89.6 +/- 12.6 pg. per milliliter) (p = less than 0.05 and less than 0.005, respectively). UV DHT and UA DHT showed no significant difference between male and female neonates. In midtrimester pregnancy, amniotic fluid T (AFT) was 165.2 +/- 15.4 pg. per millitier in pregnancies with a male fetus and was significantly higher (p = less than 0.001) than in pregnancies with a female fetus (mean +/- S.E. = 27.6 +/- 2.6 pg. per millitier). In late pregnancy, AFT levels were similar to those of early pregnancy, but a considerable overlap in AFT between fetuses of both sexes was observed. DHT was not detectable in amniotic fluid. The results suggest the potential value of AFT for determining fetal sex in midtrimester pregnancy and confirm that maternal T and DHT increase during pregnancy and that cord T levels reflect fetal gonadal androgen synthesis.

Amniotic Fluid↗
PubMed1977

Isolation of prolactin from human amniotic fluid.

Amniotic fluid, obtained from women at term, was centrifuged and concentrated by ultrafiltration. The concentrated amniotic fluid was purified by gel filtration on Sephadex G-100 and ion-exchanged chromatography on DEAE-cellulose. The fractions obtained during purification procedures were assayed for prolactin and somatotropin activities by respective radioimmunoassays. The prolactin-rich fraction obtained from ion-exchange chromatography was further purified by isoelectric focusing. A yield of 0.21 mg of highly pruified prolactin containing 40 units/mg was obtained from 1 liter of the amniotic fluid. The prolactin was free of somatotropin and human placental lactogen.

Amniotic Fluid↗
PubMed1977

Recovery of prolactin from acetone-dried human pituitary glands.

An improved method is described for the purification of prolactin from the same batch of acetone-dried pituitary glands which is used for the isolation of other anterior pituitary hormones. The residue obtained after the extraction of the glycoprotein fraction from the pituitary acetone powder was extracted for growth hormone. The supernatant after the precipitation of growth hormone at 50% ethanol concentration was adjusted to 85% in ethanol. To the supernatant obtained from that step an equal volume of acetone was added to precipitate the 'PRL fraction.' This fraction was further purified by gel filtration on Sephadex G-100, ion-exchange chromatography on DEAE-cellulose and isoelectric focussing. A yield of 23 mg prolactin, 37 U/mg, was obtained per 1000 g pituitary acetone powder.

Acetone↗
PubMed1977

Human chorionic gonadotropin and its subunits in hydatidiform mole and choriocarcinoma.

Serum human chorionic gonadotropin (hCG) was measured by a radioreceptorassay (RRA) and radioimmunoassay (RIA) and serum hCG-beta and hCG-alpha by RIA in 10 patients with intact mole, 3 patients with choriocarcinoma, and 4 patients with hydatidiform mole during treatment. hCG levels by RRA were higher in 5 of 10 molar pregnancies and ranged from 20,900 to 100,000 ng/ml and from 30,000 to 100,000 ng/ml by RIA. hCG levels by RRA and RIA paralleled one another closely during treatment of hydatidiform mole. hCG-alpha was higher than hCG by RRA and RIA and hCG-beta in molar pregnancies, in the uterine venous blood draining a uterine choriocarcinoma, and during chemotherapy of choriocarcinoma. In 2 of 3 choriocarcinoma patients who eventually developed cerebral metastases, hCG-alpha increased while hCG and hCG-beta were declining or negative. hCG-beta was usually lower than hCG or hCG-alpha in all the cases studied. These results demonstrate the production of free alpha and beta subunits in trophoblastic disease. Further, due to the biospecificity, simplicity, and rapidity, the RRA of hCG is a sueful diagnostic aid during treatment of trophoblastic neoplasia until the levels fall to within the sensitivity range of the assay. Finally, the RIA of hCG, hCG-beta, and hCG-alpha, which requires several days, should be performed until they become negative or fall within normal range.

Choriocarcinoma↗
PubMed1977

Radioreceptorassay of luteinizing hormone-human chorionic gonadotropin in urine: detection of the luteinizing hormone surge and pregnancy.

A radioreceptorassay of luteinizing hormone (LH)-human chorionic gonadotropin (hCG), using plasma membranes of bovine corpora lutea, has been extended to the detection of the midcycle LH peak and subsequent pregnancy in morning and 24-hour urine samples on days 10 to 12 following ovulatiobjects as determined by radioreceptorassay and radioimmunoassay were 45 ng and 20 ng/ml of urine, respectively; in 24-hour urine samples, mean levels of 39 ng and 17 ng of LH/ml, respectively, were found. A sustained rise in hCG was detected by the radioreceptorassay from 10 to 12 days after conception, and by day 15 the hCG levels were in the range of the midcycle LH range; this finding was confirmed by the radioimmunoassay of hCG.

Adult↗
PubMed1976

Plasma testosterone and dihydrotestosterone in ovulatory and anovulatory cycles.

Daily plasma testosterone (T) and dihydrotestosterone (DHT) as well as plasma lueteinizing hormone, plasma estradiol (E2) and plasma progestrone (P) were measured by radioimmunoassay in seven ovulatory cycles and in three anovulatory cycles. In ovulatory cycles, plasma T ranged from 110 to 637 pg. per milliliter, while plasma DNT ranged from 10 to 246 pg. per milliliter. There is an increase in the mean plasma T during the early follicular phase of the cycle with a fall on the day of ovulation. Plasma T levels rise again during the early luteal phase and drop during the late luteal phase of the cycle. Plasma E2 rises during the follicular phase with a preovulatory surge followed by a drop after ovulation and a subsequent secondary rise. Plasma P was less than 1 ng. per milliliter during the follicular phase and increased to above 5 ng. per milliliter after ovulation, reaching levels of 20 to 25 ng. per milliliter during the luteal phase. In anovulatory cycles, there is random fluctuation with no well-defined patterns. Plasma P remained below 1 ng. per milliliter throughout the cycle. The finding of maximum T levels prior to midcycle may reflect increased T production by the ovaries in response to increasing levels of follicle-stimulating hormone. There is little fluctuation in the levels of T during the menstrual cycle. These findings obviate the need for multiple plasma T estimations in the assessment of women with hirsutism, polycystic ovarian disease, and the testicular feminization syndrome.

Adult↗
PubMed1976

Amino acid sequence of the beta subunit of follicle-stimulating hormone from human pituitary glands.

The beta subunit of follicle-stimulating hormone (FSH-beta) from human pituitary glands was reduced and S-aminoethylated prior to thermolytic, tryptic, and chymotryptic digestions. Each digest was gel-filtered on Sephadex G-50 to seperate the glycopeptides. The glycopeptides and the peptides were isolated by high voltage paper electrophoresis at pH 6, 3.5, and 2.0. The purity of the isolated peptides was confirmed by amino acid analyses. The amino acid sequences of peptides were determined by Edman degradation followed by subtractive amino acid analysis and, in certain cases, confirmed by dansylation. COOH-terminal sequences of the peptides were determined by digestion with carboxypeptidases A and B and by hydrazinolysis. The tryptophan content of human follicle-stimulating hormone, of the beta subunit of human follicle-stimulating hormone, and of the glycopeptides obtained from the enzymic digests was determined by fluorescence spectra, titration against N-bromosuccinimide, colorimetric estimation with p-dimethyl aminobenzaldehyde, hydrolysis with methane sulfonic acid containing 0.2% tryptamine followed by amino acid analysis, microbiological assay, and sequence analysis. The presence of 1 tryptophan residue in the beta subunit was indicated.

Amino Acid Sequence↗
PubMed1976

Use of receptors in the preparation of LH-free serum.

The use of specific receptors has provided a novel method to prepare LH-free serum. LH-free serum was used in RRA to measure basal LH levels in serum of men and women during menstrual cycle as well as during post menopause.

Cell Membrane↗
PubMed1976

Serum testosterone and dihydrotestosterone in patients with trophoblastic disease.

Serum testosterone (T) and dihydrotestosterone (DHT) were measured by radioimmunoassay in 14 patients with unaborted hydatidiform mole and in 16 patients with normal pregnancy of similar gestational age. Serum human chorionic gonadotropin (hCG) was measured by the radioreceptor assay in patients with hydatidiform mole. Serum T ranged from 0.27 to 5.39 ng/ml with a mean +/- SE of 2.21 +/- 0.45 ng/ml in patients with hydatidiform mole mole and from 0.20 to 2.40 ng/ml with a mean +/- SE of 0.80 +/- 0.14 ng/ml in patients with normal pregnancy, the difference being statistically significant (P = less than 0.005). Similarly, patients with molar pregnancies had a significantly higher (P = less than 0.005) serum DHT (range: 0.09 to 0.62 ng/ml; mean +/- SE: 0.29 +/- 0.05 ng/ml) than patients with normal pregnancies (range: 0.04 to 0.28 ng/ml; mean +/- SE 0.12 +/- 0.02 ng/ml). There was no significant correlation between uterine size or serum hCG and serum T or DHT. The possible sources of the elevated serum T and DHT and the lack of hirsutism or virilization in patients with trophoblastic disease are discussed.

Dihydrotestosterone↗
PubMed1976

Results of the first 1000 radioreceptorassays for the determination of human chorionic gonadotropin: a new, rapid, reliable, and sensitive pregnancy test.

One thousand radioreceptorassays for human chorionic gonadotropin (hCG) for the diagnosis of pregnancy were analyzed under eight categories. The high sensitivity (50 pg/ml) and specificity, coupled with performance time of the assay (1 hour), provided a new modality for the early diagnosis and management of normal and abnormal pregnancy in the first trimester. The radioreceptorassay becomes positive 1 week after conception. In the normal pregnancy this assay has been 100% correct at the time of the first missed menses. All ectopic pregnancies demonstrated positive tests, and no false negatives occurred. On the other hand, a negative assay excluded ectopic pregnancy.

Abortion, Incomplete↗
PubMed1976

Detection of human chorionic gonadotropin in blood of regularly bleeding women using copper intrauterine contraceptive devices.

Highly sensitive and specific radioreceptorassay and radioimmunoassay of human chorionic gonadtropin (hCG) have been used in the detection of hCG in random serum samples during the luteal phase of the menstrual cycles of 200 women and in daily serum samples obtained a few days prior to expected ovulation through the luteal phase in 3 women with regular bleeding patterns and using a copper intrauterine device (IUD). Twelve to nineteen per cent of IUD users showed hCG in serum during the luteal phase, indicating that the presence of the IUD, while permitting fertilization, probably causes interference through degeneration of the blastocyst and consequent lack of implantation.

Chorionic Gonadotropin↗
PubMed1975

Primary amino acid sequence of follicle-stimulating hormone from human pituitary glands. I. alpha subunit.

Follicle-stimulating hormone of a high state of physicochemical and biological purity was isolated from acetone-preserved human pituitary glands. The follicle-stimulating hormone was dissociated into alpha and beta subunits by treatment with 8 M urea and the subunits were separated by ion exchange chromatography on DEAE-Sephadex A-25. The subunits were freed of undissociated or reassociated follicle-stimulating hormone by gel filtration on Sephadex G-100. For the establishment of the primary amino acid sequence, the alpha subunit was reduced and either carboxyamidomethylated or S-aminoethylated prior to a thermolytic or a tryptic digestion. Each digest was gel filtered on a column of Sephadex G-50 to separate the glycopeptides from the peptides. The glycopeptides and the peptides were purified further by sequential gel filtration on Sephadex G-25, G-15, and Bio-Gel-P-2 and were isolated by high voltage electrophoresis at pH 6, 3.5, and 2. The purity of the isolated peptides was ascertained further by amino acid analysis. The amino acid sequences of the peptides were determined by Edman degradation followed by subtractive amino acid analysis. COOH-terminal sequences were established by digestion with carboxypeptidases A and B. The primary amino acid sequence of human follicle-stimulating hormone-alpha is identical to that of human chorionic gonadotropin-alpha and differs from that of human luteinizing hormone-alpha in having the tripeptide Ala-Pro-Asx- at the NH2-terminal end.

Amino Acid Sequence↗
PubMed1975

The use of a radioreceptorassay of human chorionic gonadotropin for the diagnosis and management of ectopic pregnancy.

The radioreceptorassay of human chorionic gonadotropin (hCG), with a sensitivity of 50 pg or 3 mIU/ml of plasma, has provided almost 100% reliability in detecting pregnancy after the first missed cycle. This test may be performed within 1 hour and is ideally suited to the clinical detection of ectopic pregnancy, especially in patients who require immediate surgical intervention. Thirteen patients with suspected ectopic pregnancy were evaluated by the radioreceptorassay, one of whom was followed with four separate determinations. The results of the assay were subsequently compared with those of hemagglutination pregnancy tests, clinical symptoms, and pathologic findings. All of the patients were diagnosed accurately by the radioreceptorassay, even when hemagglutination tests yielded a false indication of pregnancy. By this assay, the hCG levels during ectopic pregnancies are generally lower than those found during a normal intrauterine pregnancy; in addition, pregnancy may be detected much earlier (prior to the rupture) than is possible by hemagglutination tests. Furthermore, the diagnosis of ectopic pregnancy may be excluded for patients admitted to the hospital with acute abdominal emergencies.

Acromegaly↗
PubMed1975

Application of a radioreceptorassay of human chorionic gonadotropin in the diagnosis of early abortion.

A radioreceptorassay for human chorionic gonadotropin (hCG) was used to detect pregnancy as early as 6 to 8 days following conception and to predict spontaneous abortion as early as 8 to 10 days after conception in subjects whose hCG levels were lower than those occurring during normal pregnancy of the same duration. The evidence for the specific measurement of hCG was further provided by the correlation of plasma hCG levels measured by radioimmunoassay using antisera specific for hCG-beta and radioreceptorassay of hCG. By virtue of its sensitivity and specificity, the radioreceptorassay of hCG allowed early and accurate prediction of spontaneous abortion in 15 patients.

Abortion, Threatened↗
PubMed1975

The lh-hcg receptor of human ovary at various stages of the menstrual cycle.

Receptors specific for hCG were found in human corpora lutea and follicles. hCG and LH were found to bind at a similar receptor site. The dissociation constant for hCG ranged from 10-minus 10 to 10-minus 11 mol/1 in human corpora lutea. The number of binding sites for 125-I-hCG ranged from 10-minus 14 to 10-minus 15 moles/mg protein in human corpora lutea. The binding of 125-I-hCG to ovary was found to vary at different stages of the menstrual cycle. The binding of 125-I-hCG to human ovaries increased on days 13-15 of the cycle, then declined slightly, and increased again on days 22-23. Following day 23, there was a slow decline until day 27 when binding activity could no longer be measured. No binding could be measured by the corpus luteum after the onset of menstruation or in corpora albicans.

Binding Sites↗