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O Djahanbakhch

Publications and source records attributed to O Djahanbakhch.

At least 19 recordsLinked to original sources
PubMed1996

Angiotensin II stimulates sperm motility.

The physiological factors which induce and maintain mammalian sperm maturation and motility generally remain unclear, although several agents are known to be involved. We recently described the application of immunocytochemical and immunoblotting methods to identify the angiotensin II type 1 (AT1) receptor in the tails of ejaculated rat and human sperm, and gave evidence to show that angiotensin II may promote sperm motility. These data are extended here by the application of a computerised sperm tracking system (the Hobson Sperm Tracker) to demonstrate that AII has actions on specific motility parameters, including curvilinear velocity, straight line velocity, and amplitude of lateral head movement. Since local tissue renin-angiotensin systems are present in both male and female tracts, the data suggest that angiotensin II has a role in the maintenance of sperm function and fertility.

Angiotensin I↗
PubMed1996

Evidence for the Bauman variant in Kallmann's syndrome.

BACKGROUND AND OBJECTIVE: Idiopathic hypogonadotrophic hypogonadism (IHH) is a condition of gonadotrophin releasing hormone (GnRH) deficiency. IHH associated with anosmia is Kallmann's syndrome. A variant has been described by Bauman where a patient with Kallmann's syndrome apparently regained normal hypothalamo-pituitary function 2 years after the initial diagnosis. GnRH secretory activity can be assessed by measuring LH pulsatility. Our objective was to define the pattern of LH pulsatility in men with IHH and Kallmann's syndrome compared with those of normal controls, and to determine whether there is evidence for a Bauman variant of Kallmann's syndrome. DESIGN: Patients with IHH and Kallmann's syndrome were recruited from the endocrine clinic. Long-term hormone replacement therapy was discontinued. LH pulsatility was determined. PATIENTS: Three men with IHH, 3 men with classical Kallmann's syndrome and 5 normal male volunteers. MEASUREMENTS: Baseline serum FSH, LH and testosterone. Intensive blood sampling every 10 minutes for serum LH from 1000 to 1600 h during the day and 2200 to 0400 h during the night to measure LH pulsatility. RESULTS: The volunteer group showed normal LH pulsatility. In the patient group, LH secretion was apulsatile in one, showed significantly diminished amplitude in four, and there was normal pulsatility in one patient which remained normal 5 months later. CONCLUSION: Three patients with idiopathic hypogonadotrophic hypogonadism and 2 with Kallmann's syndrome had variable degrees of GnRH deficiency. One patient with Kallmann's syndrome had apparently normal GnRH activity, which remained normal 5 months later. This patient appears to have the Bauman variant of Kallmann's syndrome.

Adult↗
PubMed1996

Screening for Down's syndrome: experience in an inner city health district.

OBJECTIVE: To review the experience of Down's syndrome screening in an inner city health district. DESIGN: In this retrospective study the names of the women were obtained from the Regional Cytogenetic Laboratory and District Down's Syndrome Register. Antenatal notes of the mothers were studied. Maternal age during the affected pregnancy, screening test performed if any, gestational age at booking and at screening, screening test results, and pregnancy outcome were reviewed. SETTING: An inner city health district. POPULATION: Down's syndrome cases diagnosed prenatally and postnatally. INTERVENTIONS: None. RESULTS: Antenatal diagnosis of Down's syndrome was made in 15/45 women (33.3%); Edwards' syndrome was diagnosed antenatally in 2/5 women. Screening was not performed in eight women (17.8%) whose infants were affected by Down's Syndrome; it was also not performed in one woman whose baby was affected by Edwards' syndrome due to late presentation to the antenatal clinic or loss of the blood sample. Nineteen women (42.2%) with a Down's syndrome pregnancy and two women with a Edwards' syndrome pregnancy had had a negative screening test. Three women had had a positive screening test but declined amniocentesis. Among those who had a screening test, the overall detection rate of screening was 48.6% (18/37) for Down's syndrome and 50% (2/4) for Edwards' syndrome. The detection rates in different ethnic groups did not show significant difference. Four women chose not to have termination following diagnosis of Down's syndrome, giving a total reduction rate of 21%. CONCLUSION: Screening programmes for Down's syndrome have not yet resulted in a substantial reduction in the number of affected babies. In addition to trials at developing screening programmes with better detection rates, efforts should be made to improve the provision of the screening service and the quality of antenatal care in general with emphasis on early presentation and optimal understanding of the implications of the tests.

Adult↗
PubMed1996

Angiotensin II receptors and angiotensin II stimulation of ciliary activity in human fallopian tube.

Using an antibody (6313/G2) directed against a specific sequence in the extracellular domain of the type 1 angiotensin II receptor (AT1), we demonstrated the presence of angiotensin II (AII) receptors in human fallopian tube. Immunoperoxidase staining for AT1 receptor showed positive staining in the epithelium of the tubal mucosa. The intensity of staining varied depending upon the hormonal status at the time of salpingectomy, being strongest in the proliferative phase of the ovarian cycle and weakest after menopause. Ligand binding assay confirmed that the AII receptor concentration was highest in the mucosa of fallopian tubes from premenopausal women. Mucosa from the ampullary segment had higher concentrations of AII receptor than the fimbrial and isthmic segments in both premenopausal and postmenopausal women. Displacement studies using specific AII receptor subtype antagonists showed that approximately 60% of the total activity could be displaced by CGP42112B (type 2 specific) and 40% by losartan (AT1 specific). Immunoblotting confirmed that the antibody detected a protein of approximately 60 kDa. Functional studies showed that AII had a stimulatory action on tubal ciliary beat frequency, but had no significant effect on myosalpingseal activity. This effect was achieved at nanomolar concentrations of AII; further increases in the AII concentration were without additional effect. The stimulatory effect of AII was inhibited by the specific AT1 antagonist losartan, whereas the type 2 antagonist, CGP42112B, had no effect. The data demonstrate that AII may play an important role in ovum transport and fertility.

Angiotensin II↗
PubMed1995

Type 1 angiotensin II receptors in rat and human sperm.

The physiological factors which induce and maintain mammalian sperm maturation and motility generally remain unclear, although several agents are known to be involved. We describe here the application of immunocytochemical and immunoblotting methods to identify the angiotensin II type 1 (AT1) receptor in the tails of ejaculated rat and human sperm. Motility data on stimulated and unstimulated sperm from volunteers and patients attending fertility clinics showed that angiotensin II may increase both the percentage of motile sperm and their linear velocity, while the specific AT1 receptor antagonist DuP753 inhibited the action of angiotensin II on the percentage of motile sperm. In rat seminiferous tubules, AT1 receptors were present in primary spermatogonia and in spermatid tails, but immunoreactivity was not seen in sperm contained in caput or cauda epididymis, showing that AT1 receptor function is regulated during transit through the reproductive tract. Since local tissue reninangiotensin systems are present in both male and female tracts, the data suggest that angiotensin II has a role in the maintenance of sperm function and fertility.

Angiotensin II↗
PubMed1994

Epithelial cell coculture and the induction of sperm capacitation.

OBJECTIVE: To investigate the influence of cultured human oviductal epithelial cells on the movement characteristics of human spermatozoa. DESIGN: Human spermatozoa were cultured with monolayers of human epithelial or Vero cells or conditioned media derived from these cell types. The viability and movement characteristics of the cells was subsequently analyzed at 4, 24, and 48 hours. SETTING: University hospital and Medical Research Council laboratories. PATIENTS, PARTICIPANTS: Volunteer donors. MAIN OUTCOME MEASURES: Movement characteristics of human spermatozoa. RESULTS: The presence of both Vero and oviductal epithelial cells, but not conditioned media, had a general promoting effect on sperm survival, significantly enhancing sperm viability and motility for up to 48 hours of culture. In addition, the presence of oviductal epithelial cells had a specific, significant stimulatory effect on sperm capacitation, enhancing the incidence of hyperactivated motility after 4, 24, and 48 hours of culture. Significantly, this effect was not observed with cocultures containing Vero cells. CONCLUSIONS: The coincubation of human spermatozoa with human oviductal epithelial cells provides a convenient system for the induction and analysis of sperm capacitation.

Adult↗
PubMed1994

A simple technique for the long-term non-polarised and polarised culture of human fallopian tube epithelial cells.

Fallopian tubes were obtained from 25 women undergoing abdominal hysterectomy. Pieces of fallopian tube mucosa were placed in culture flasks containing minimum essential medium in Earle's salts supplemented with fetal bovine serum. First passage was carried out after 7-10 days and subcultures in 4-5 days. For polarised cell culture, epithelial cells were seeded onto an extracellular matrix system. New epithelial cells were seen on day 2-3 of the primary culture and epithelial patches on day 7-10. Cells reached confluence in 4-5 days in subcultures. The cells could be subcultured for 7-11 passages with a life span of 42-60 days. Epithelial origins of the cells were confirmed by immunofluorescence staining with anti-cytokeratin antibody. Polarised cells showed a columnar pattern, microvilli on their apical surface and basally located nucleus whereas non-polarised cells were flat. It was concluded that the human fallopian tube epithelial cells can be cultured in vitro to create non-polarised and polarised cell layers by using a simple and reproducible technique and this system can be a potential model to study function of the fallopian tube.

Adult↗
PubMed1993

In-vitro synthesis of total protein and placental protein PP14 by the fallopian tube mucosa: variation in relation to anatomical site, the ovarian cycle and the menopause.

De-novo synthesis and secretion of protein by short term explants of mucosa from each anatomical section of the Fallopian tube and endometrium of pre-menopausal (n = 25) and tubal mucosa of post-menopausal (n = 5) women were studied by demonstration of incorporation of radiolabelled L-[35S]methionine and one-dimensional SDS-polyacrylamide gel electrophoresis. A consistent finding in 25 pre-menopausal women was the presence of a 25 kDa protein band synthesized by tissue obtained throughout the ovarian cycle. Western blotting demonstrated that this protein band contained placental protein 14 (PP14)-like immunoreactivity in the proliferative (n = 2) and luteal phase (n = 2) of the ovarian cycle. To determine if there is quantitative variation in total protein and PP14 synthesis and secretion during the ovarian cycle, the total quantities of protein and PP14 synthesized were determined by Coomassie Brilliant Blue staining and radioimmunoassay respectively. Analysis of the results of total protein assay revealed statistically significant differences in relation to the anatomical origin of the study tissue (P < 0.01), the stage of the ovarian cycle (P < 0.04) and the manner in which each anatomical site varied during the ovarian cycle (P < 0.01), the endometrium being significantly different from the Fallopian tube. When the data for PP14 synthesized by the Fallopian tube mucosa were analysed, these effects were not seen. PP14 was not detected in the culture media of Fallopian tube mucosa obtained from post-menopausal women.

Adult↗
PubMed1993

Evidence for the in-vitro de-novo synthesis of immunoglobulin and a previously undescribed 17 kDa protein (TEP-2) by the mucosa of the fallopian tube.

De-novo synthesis and secretion of proteins by short-term explants of matched Fallopian tube mucosa and endometrium were studied using radiolabelled L-[35S]methionine and [3H]glucosamine. To compare directly each anatomical site of the Fallopian tube and endometrium from the same source, newly synthesized proteins were separated on one-dimensional polyacrylamide gel electrophoresis and examined by auto-radiography. De-novo synthesis of two protein bands provisionally designated as tubal epithelial protein 1 (TEP-1) and tubal epithelial protein 2 (TEP-2), was observed in explants of the Fallopian tube mucosa obtained from each anatomical site throughout the ovarian cycle (n = 20). TEP-2 was not apparent in tubal mucosa obtained from post-menopausal women (n = 5). De-novo synthesis of TEP-1 and TEP-2 was not apparent in autoradiographs of radiolabelled proteins from short-term explants of endometrium. From the autoradiographs the molecular mass of TEP-1 and TEP-2 was calculated to be 25 kDa and 17 kDa, respectively. Incorporation of glucosamine into newly synthesized protein occurred in TEP-2 but not TEP-1. TEP-1 was observed to be immunochemically identical to immunoglobulin kappa light chains.

Adult↗
PubMed1992

Salpingoscopic findings in women undergoing sterilization.

We report the results of a prospective study carried out to investigate the appearance of the Fallopian tube lumen in 30 apparently normal women with a normal reproductive career, patient Fallopian tubes and a normal pelvic appearance at laparoscopy. The salpingoscopic appearance of the ampulla and fimbria of both Fallopian tubes was normal in 20 women. Amongst the other 10 women there were intratubal adhesions (n = 2), fronds attached to mucosal folds (n = 4), irregular blood vessels in mucosal folds (n = 2), unusual mucosal folds (n = 3) and black 'spots' within mucosal folds (n = 3). In three women who underwent salpingoscopy during the preovulatory phase of the ovarian cycle, the mucosal fold edges appeared rounded and contained blood vessels with brightly reflective walls. Our findings suggest that there is variation in the endoscopic appearance of the tubal lumen in women with a normal reproductive career. Some of these findings may be perceived to be tubal pathology causing subfertility.

Culdoscopy↗
PubMed1986

An investigation of maternal and neonatal platelet function.

We have previously shown that the human placenta possesses a potent platelet antiaggregatory activity which is probably due to an ADPase. This led us to investigate platelet aggregation (in response to: adenosine diphosphate; adrenaline; collagen) in maternal blood samples obtained pre- and post-delivery and in cord blood at the time of delivery. Platelet aggregation in maternal samples did not differ significantly pre- and post-delivery, nor did it differ significantly from platelet aggregation observed in age-matched, non-pregnant women. On the other hand, platelets obtained from cord blood samples were insensitive to adrenaline even when very high concentrations (100 mumol/l) of this agonist were used. This lack of response to adrenaline could be overcome by incubation of cord platelet rich plasma (PRP) with sub-aggregatory doses of collagen or ADP or by standing PRP at room temperature for 2-3 h. ADP-induced aggregation was also diminished in cord PRP samples but this was only significant at the lowest ADP concentrations. The physiological significance of these findings is unclear but it may be of relevance that plasma catecholamine levels are high in neonates. Some adults show a defect of aggregation with absence of response to adrenaline, suggesting that neonatal platelet function patterns may persist in some adults.

Adenosine Diphosphate↗
PubMed1985

An evaluation of routine early pregnancy ultrasonography.

A review of 1 000 pregnancies in which routine early pregnancy scanning was performed is reported. Ultrasound predicted accurately (to within +/- 14 days) the date of confinement in more than 90% of women who were unsure of their dates. Clinical estimation of gestation age compared well with ultrasound report in 90% of singleton pregnancies. Scanning diagnosed 3 out of 4 lethal congenital abnormalities in early pregnancy. The diagnosis of multiple pregnancy and placenta praevia have no immediate clinical implication in early pregnancy. Early pregnancy scan is recommended for women who are uncertain of their last menstrual period and for those with identified early pregnancy risks. Routine use of ultrasonography in early pregnancy should be related to the identified need of the population served and should be employed with caution. Where the policy of routine scanning is adopted, optional information is obtained when the procedure is carried out between the 14th and 18th week of gestation. Clinical pelvic examination in early pregnancy remains a valuable practice for the estimation of gestational age.

Adolescent↗
PubMed1984

Pulsatile release of LH and oestradiol during the periovulatory period in women.

Blood was collected every 8 h in five women from Day 10 of the menstrual cycle for 5-7 d for the measurement of LH, oestradiol and progesterone. In all women the LH surge started between 2400 and 0800 h before there was any significant decline in the concentration of oestradiol. In order to investigate the pulsatile secretion of LH and estradiol during the mid-cycle surge, blood samples were collected every 5 min for up to 5 h. Immediately before and during the LH surge there were numerous episodic pulses of LH with an interpulse interval (44 +/- 7 min) very similar to that observed in two women with hypergonadotrophic hypogonadism (48 min). The concentration of oestradiol fluctuated in a similar manner although it was not always possible to relate each pulse of oestradiol to a corresponding pulse of LH. The mid-cycle surge of LH is characterized by frequent pulses of high amplitude. These results are compatible with the view that the positive feedback effect of oestradiol is due not only to enhanced sensitivity of the anterior pituitary to LHRH but also to the high frequency of LHRH pulses released from the hypothalamus.

Adult↗