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A Jolivet

Publications and source records attributed to A Jolivet.

At least 55 records · Page 3Linked to original sources
PubMed1988

Radioimmunoassay of progesterone receptor in human tissues: application to breast cancer.

A radioimmunoassay method to measure progesterone receptor in rabbit and human tissues was devised and applied to human breast cancer. A specific progesterone receptor antibody was prepared by purifying rabbit receptor by immunoaffinity chromatography, sodium dodecylsulphate-polyacrylamide gel electrophoresis and injection of the isolated 110,000 dalton receptor band into a goat. Immunoblot studies of progesterone target and non-target tissues showed the specificity of the antibody, which was used at a dilution of 1/45,000. The tracer consisted of 125I-labelled electroeluted 110,000 dalton receptor. The sensitivity of the method was 1 fmol/tube for the rabbit receptor and 3 fmol/tube for the human receptor. The intra-assay coefficient of variation was 11% for tumours positive for the progesterone receptor and 9.9% for those on the borderline (10-30 fmol receptor/mg protein). The interassay coefficients of variation were 20 and 19% respectively. The correlation between the radioimmunoassay and a steroid-binding assay was studied in 40 tumour biopsies. In 39 cases, very good correlation was found (r = 0.99); in a single case an immunoreactive protein was detected which apparently bound steroid poorly. One important feature of this method was that receptor immunoreactivity remained unchanged when either the tissue or the cytosol was exposed to a temperature of 20 degrees C for relatively long periods of time. Under the same conditions the steroid-binding capacity declined rapidly. This characteristic of the radioimmunoassay may prevent errors due to improper handling of tissue samples. Such stability was not observed for oestrogen receptors when measured by a sandwich immunoenzymatic method after incubation of tissue at 20 degrees C.

Animals↗
PubMed1987

Immunocytochemical study with monoclonal antibodies to progesterone receptor in human breast tumors.

Mouse hybridomas secreting monoclonal antibodies against rabbit uterine progesterone receptor (PR) have been prepared. Several of these immunoglobulins exhibited high affinity towards human progesterone receptor and two (LET 126 and LET 64) were selected as giving the best immunoperoxidase staining of human progesterone target organs. Using the indirect peroxidase-antiperoxidase method of Sternberger, optimal conditions for demonstrating PR involved brief fixation of frozen sections with formaldehyde-containing fixatives, among them picric acid-paraformaldehyde. This method allowed us to detect the receptor in breast carcinoma epithelial cells, T47D cell line, and uterine endometrium and myometrium. No staining was observed in intestine and muscle. Specific staining for PR was confined to the nucleus, irrespective of the concentration of progesterone in the blood of the patient. In a preliminary study of 27 human breast cancers by the immunocytochemical method, the presence or absence of nuclear staining for PR correlated well with the concentration of cytosolic progesterone receptor determined by a steroid-binding assay on tumor extracts. Differences in the intensity and distribution of staining within a section were observed, suggesting heterogeneity of the PR content of breast cancer cells. In 19 tumors, the immunocytochemical method for PR localization was also used in combination with a slightly modified Abbott ER-ICA staining for estrogen receptor to compare the distribution of both receptors within the same biopsy on adjacent frozen sections. Various combinations of estrogen receptor and PR contents that have been determined by steroid-binding assay have also been detected by the double immunocytochemical assay.

Antibodies, Monoclonal↗
PubMed1985

One-step immunoaffinity purification of active progesterone receptor. Further evidence in favor of the existence of a single steroid binding subunit.

A very high capacity immunoaffinity matrix for the purification of progesterone receptor was prepared by cross-linking a monoclonal antireceptor antibody to protein A-Sepharose through the Fc fragment. The monoclonal antibody was selected for its property of losing affinity for the receptor at pH 10.5, i.e., in conditions where the receptor remains stable for extensive periods of time. This made it possible to elute active receptor form the immunosorbent. From crude rabbit uterine cytosol the steroid-receptor complexes were purified in a single step. A 1-mL column (containing 7 mg of monoclonal antibody) bound 1600 pmol of steroid-receptor complexes of which 79.5% were eluted. The overall yield of purification was 49%. The specific activity of the purified steroid-receptor complexes was 6.71 +/- 0.79 nmol of bound steroid/mg of protein (mean +/- SE of four experiments). The purified receptor consisted of a mixture of 110 000- and 79 000-dalton forms. The latter appeared to be produced by proteolysis of the larger form during purification since immunoblot experiments showed that, at the start of purification, the 110 000-dalton form was present in overwhelming majority (80-95%) in the uterine cytosol and that the 79 000-dalton form only appeared during purification. This conclusion was also supported by the peptide analysis of both forms of receptor: the purified receptor was denatured and labeled with 125I; the 110 000- and 79 000-dalton forms were isolated by gel electrophoresis in denaturing conditions and electroelution and were then submitted to mild or extensive digestions by trypsin, chymotrypsin, and protease V8 from Staphylococcus aureus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

A longitudinal study of cyclic nucleotide phosphodiesterase activity and its relationship with nucleic acid content in the myometrium of cynomolgus monkeys (Macaca fascicularis) between days 39 and 162 of gestation.

Cyclic AMP and cGMP phosphodiesterase (PDE) activities and nucleic acid contents were assayed in crude homogenates prepared from biopsies excised between days 39 and 162 of gestation (normal full length of gestation: 165 days) in outer and inner layers of the macaque myometrium. In both layers, kinetic analysis of PDE indicated high (apparent Km 2 X 10(-6) M) and low (apparent Km 2 X 10(-5) M) affinity component for each substrate. When measured in high-affinity conditions, specific activities were elevated around day 40 and beyond day 130 of gestation. By contrast, low values were observed between days 50 and 100. They were related to the decrease of the Vmax values (expressed either per milligram protein or per microgram DNA). No significant differences were observed between outer and inner layers. Variations of tissue DNA and RNA were demonstrated throughout gestation indicating that both hyperplasia and hypertrophy were involved in uterine growth. Unlike DNA, RNA content (and consequently the RNA:DNA ratio) in the inner layer always remained above the values of the outer layer. In both layers, the RNA:DNA ratio, which presumably reflects the rate of protein synthesis and the PDE activity, reached maximum values at the same time.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1985

Influence of the oral administration of micronized progesterone on plasma and tissue levels of steroids in human pregnancy.

A single dose of micronized progesterone, orally administered to women at different stages of pregnancy, induced an immediate increase in the plasma levels of progesterone. Progesterone was administered to another group of women just before elective cesarean section. Levels of progesterone, oestradiol-17 beta and oestrone were determined in plasma, placenta and at different sites of the myometrium obtained during the surgical procedure. Results were compared to those observed in a control group of women who did not receive progesterone. Progesterone levels demonstrated a marked increase in plasma and in the whole myometrium 150 min after administration; the levels then decreased rapidly to control values within one hour. The concentrations of progesterone in the placenta did not show any change. Evident modifications of the oestrogen levels appeared in the myometrium and in the placenta after the administration of progesterone whereas no change occurred in the plasma. No difference was observed in estradiol-17 beta in the myometrium whereas an increase was seen in the placenta. Estrone levels decreased in the myometrium and in the placenta. This study demonstrates a prompt delivery of an orally administered natural progesterone to the myometrial target tissue and subsequent modifications in the estrogen pattern. This provides a theoretical mechanism for the clinical use of progesterone in the prevention of premature labor.

Administration, Oral↗
PubMed1984

Oral administration of micronized natural progesterone in late human pregnancy. Effects on progesterone and estrogen concentrations in the plasma, placenta, and myometrium.

A single dose of micronized oral progesterone was administered to 15 pregnant women immediately prior to elective cesarean section. Levels of progesterone, 17 beta-estradiol, and estrone were measured in the plasma, in the placenta, and at different sites in myometrium obtained during the surgical procedure. Results were compared to those observed in a control group of women who did not receive progesterone. Progesterone levels demonstrated a marked increase in plasma and in the whole myometrium 150 minutes after administration. The levels then decreased rapidly to control values in 1 hour. The concentrations of progesterone in the placenta did not show any changes. No difference appeared in 17 beta-estradiol levels in the plasma or the myometrium, whereas an increase was observed in the placenta. Estrone levels did not change in the plasma, but they decreased in the myometrium and in the placenta.

Administration, Oral↗
PubMed1984

RU 16117, an orally active estriol-like weak estrogen.

RU 16117, the 11 alpha-methoxy derivative of ethynyl estradiol, is an orally active weak estrogen potentially effective in the treatment of estrogen-deficiency in postmenopausal women (climacteric symptoms and severe osteoporosis). Biochemical studies have shown that RU 16117, like estriol, possesses the properties characteristic of a partial estrogen agonist/antagonist. RU 16117 binds to the cytosol estrogen receptor (ER) to form a complex which dissociates much faster than the estradiol complex. This explains its lower nuclear uptake. Furthermore, the nuclear RU 16117 complex also dissociates faster than the estradiol complex. Consequently, although low doses of RU 16117 can induce the majority of the effects of estradiol (increased polymerase A and B activities, cytosol ER replenishment, progestin receptor induction, increased uterine weight), these effects are long-lived only if the dose is considerably increased or if the compound is administered repeatedly or continuously. Since RU 16117 transiently occupies available estrogen binding sites, it can prevent the full response of estradiol. Thus, under appropriate kinetic conditions, it acts as an estrogen antagonist on the above parameters and also on DMBA-induced mammary tumors in the rat. At a daily dose of 24 micrograms for a period of 4 weeks RU 16117 led to 65% reduction in the number of already-established tumors. RU 16117 inhibits basal gonadotropin secretion and decreases the LH response to LHRH. Injection of 5 micrograms s.c. to the rat in estrus markedly inhibited the spontaneous peaks of LH, FSH and PRL measured on the afternoon of expected proestrus. Low doses which block ovulation by 100% had no detectable effect on vaginal cornification, thus suggesting a greater sensitivity at the hypothalamo-pituitary level.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1981

Binding of steroids by proteins in follicular fluid of the human ovary.

Steroid-protein interactions were studied in the antral fluid of preovulatory follicles of the human ovary. Two high affinity binding systems are described. These steroid-binding proteins do not differ from those identified in the plasma of women (transcortin and sex binding protein), as indicated by similar specificity, binding affinity, and electrophoretic pattern. Their concentrations in the fluid are either similar to or lower than those in plasma. Since the steroid concentrations in antral fluid are approximately 20- to 100-fold higher than the binding capacities of the specific steroid binders, the buffer role that many authors attribute to the proteins which bind steroids is unlikely in antral fluid.

Body Fluids↗
PubMed1978

Clinical investigation of the menstrual cycle. I. Diagram of the normal menstrual cycle.

The clinical definition of normal menstrual cycles has been attempted by using the basal body temperature charts of patients without gynecologic dysfunction who conceived in the following cycle. A second-species linear regression method has been used for statistical comparison of lengths of both follicular and luteal phases. A graphic representation of the equation of the tolerance limit about 46 normal cycles is proposed which can be considered a nomogram of the menstrual cycle.

Female↗
PubMed1978

Clinical investigation of the menstrual cycle. II. Neuroendocrine investigation and therapy of the inadequate luteal phase.

Nonhormonal drugs--diphenylhydantoin and nialamide, which act on the central nervous system and have no known endocrine activity--were given to two groups of women with distinct types of electroencephalographic patterns in an effort to regulate menstrual disorders. Equalization of the lengths of both the follicular phase and the luteal phase to the normal range was observed during the drug therapy. Forty-five per cent of the pregnancy rate was achieved in 36 of the 80 infecund patients within 4 months of treatment. The mode of action of these drugs is still unknown.

Adult↗
PubMed1978

[Effect of ergot alkaloid derivatives on milk secretion in the immediate postpartum period].

30 women received an intramuscular injection of 0.2 mg of methylergobasine immediately after delivery and then 3 tablets of 1 mg of ergotamine tartrate per mouth daily for 6 days post-partum. 28 women received no treatment after delivery. The selection of the two groups was random. The treatment with rye ergot derivatives did not have a significant effect on the quantity of milk that the infant took, nor on the infant's weight gain in the 6 first days of life.

Body Weight↗
PubMed1977

Presence of immunoassayable beta-endorphin in human amniotic fluid: elevation in cases of fetal distress.

Immunoassayable beta-endorphin is present in samples of amniotic fluid obtained in the last two weeks of pregnancy. Average concentration is approximately 300 pg. per milliliter. In all cases of suspected or recognized fetal distress, striking elevations of the beta-endorphin concentrations (twofold to 20-fold) were observed. The degree of elevation correlated with the degree of fetal distress.

Amniotic Fluid↗
PubMed1977

[Variations of non conjugated steroids in the amniotic fluid during the last weeks of pregnancy].

Levels of cortisol, estradiol and progesterone were measured in 172 amniotic fluid samples collected by amniocentesis during late pregnancy. An increase in cortisol and estradiol levels was observed three weeks before vaginal delivery of term and premature infants; in both types of delivery, onset of labor was spontaneous. In contrast progesterone levels were only slightly decreased in these cases.

Amniotic Fluid↗
PubMed1977

[Neuroendocrine investigation of the follicular phase: spontaneous and after estrogen stimulation (author's transl)].

Estrogen stimulation on days 7, 8, 9 of the menstrual cycle induces disturbances of the usual clinical and hormonal patterns. Alpha rythm (8-12 Hz) variation curve, studied by mathematical analysis, is modified, and delayed ovulation happened at its nadir. It is concluded that EEG appears as a tool for clinical neuroendocrine correlations and that this preliminary study may indicate that this estrogen positive feedback is received at the neurovegetative level.

Alpha Rhythm↗