Nitric oxide in human fetal membranes at term gestation: effect on prostaglandin E2 release.

OBJECTIVES: To examine the in vitro release of nitric oxide (NO) by human fetal membranes at term gestation and to investigate whether NO could stimulate prostaglandin E2 (PGE2) release by these tissues. STUDY DESIGN: Explants of fetal membranes (n = 17) were incubated either in the presence of sodium nitroprusside (NP), or L-Arginine (L-Arg), or bacterial lipopolysaccharide (LPS), or in the absence of the above substances (controls). NO and PGE2 concentrations in culture medium were assayed by the Griess reaction and radioimmunoassay, respectively. RESULTS: Fetal membranes spontaneously released NO in culture medium; incubation with NP increased the production of both NO and PGE2. L-Arg and LPS enhanced PGE2 output by tissues but did not influence NO production. CONCLUSIONS: An NO-generating activity might be present in human fetal membranes. NO stimulates PGE2 release by these tissues.

Interleukin-2 in human amniotic fluid during pregnancy and parturition: implications for prostaglandin E2 release by fetal membranes.

The potential role of interleukin 2 (IL-2) in human pregnancy was investigated by evaluating the following. (1) The presence and concentrations of IL-2 in amniotic fluid (AF) in 24 women at 16-18 weeks' gestation (Group 1) and in 27 women at term pregnancy, either before the onset of labor (Group 2, n = 10) or during spontaneous active labor (Group 3, n = 17). (2) The production of IL-2 by fetal membranes at term gestation (n = 7). (3) The release of prostaglandin E2 (PGE2) by the above tissues after stimulation with IL-2 (n = 10) or phytohemagglutinin (PHA) (n = 8). Immunoreactive IL-2 was detected only in AF samples obtained from women of Groups 1 and 3; the higher concentration was found in Group 1 samples; IL-2 was not detected in AF samples from women of Group 2. Tissues did not release IL-2. Both IL-2 and PHA exerted a significant stimulatory effect on PGE2 release by tissues. IL-2 stimulated PGE2 release by chorion tissue, but not by amnion tissue. The following conclusions can be drawn: (a) AF IL-2 might play a role in the maternal-fetal immune relationship during early pregnancy and, perhaps, during labor; (b) fetal membranes would not seem to represent a source of AF IL-2 in the absence of labor; (3) IL-2 might influence arachidonic acid metabolism through the cyclooxygenase pathway in the chorion tissue.

Release of arachidonic acid metabolites by human fetal membranes: interrelationship between leukotriene B4 and prostaglandin E2.

The objective of this study was to ascertain whether human fetal membranes metabolize arachidonic acid preferentially through the lipoxygenase rather than the cyclooxygenase pathway before labor and whether an interaction between lipoxygenase and cyclooxygenase products is present in these tissues. Reflected fetal membranes were obtained from 8 healthy women at term gestation who were delivered by elective repeat cesarean section before the onset of labor. Tissues were cultured either in the presence or in the absence of the calcium ionophore A23187 for 60 minutes. Leukotriene B4 (LTB4) and prostaglandin E2 (PGE2) were measured in culture medium by radioimmunoassays. Moreover, the effect of different concentrations of exogenously added LTB4 on PGE2 release was evaluated. The basal and stimulated output of LTB4 by tissues was significantly higher than that of PGE2. Addition of LTB4 significantly decreased PGE2 release by tissues. These findings suggest that in the above tissues: 1) the arachidonate lipoxygenase pathway is highly active before labor; 2) LTB4 might play a role in the regulation of PGE2 production.

Interleukin-3 stimulates prostaglandin E2 release by human fetal membranes at term gestation.

The effect of interleukin-3 (IL-3) on prostaglandin E2 (PGE2) release by human fetal membranes at term gestation was evaluated. It was found that interleukin-3 stimulates in vitro prostaglandin E2 release by these gestational tissues, suggesting that interleukin-3 might be involved in the regulation of arachidonic acid metabolism in the fetal membranes.

Influence of labour on epidermal growth factor receptor distribution of the human chorion at term gestation.

Chorion was obtained from 10 healthy pregnant women at term gestation who were delivered either vaginally (n = 5) or by elective repeat caesarean section before the onset of labour (n = 5). Epidermal growth factor (EGF) receptors in chorionic tissue were evaluated by means of freeze fracture technique (label fracture). They were found to be significantly less, but more frequently coupled, in specimens obtained after labour than before the onset of labour. These findings suggest that a functional activation of EGF receptors in human chorion might occur during labour.

Cystic ovaries in women affected with hereditary angioedema.

Polycystic ovary (PCO) syndrome is biochemically characterized by abnormal gonadotropin secretion and polycystic ovaries associated with increase in size and functional activity of stromal tissue; multifollicular ovaries (MFO) are defined by the presence of multiple cysts with no increase in stromal tissue. A central (hypothalamic-pituitary) abnormality, including high plasma beta-endorphin (BE) concentrations without simultaneous elevation of ACTH, was reported for subjects with PCO syndrome. Since we have found the presence of high plasma BE concentrations in hereditary angioedema (HANE) during attacks as well as during symptom-free periods, we studied, by means of pelvic ultrasound scanning employed to determine the prevalence of PCO and of MFO, 13 women of reproductive age affected with HANE who were not on oral contraceptives. We have found PCO in 5/13 (38.4%) and MFO in 7/13 (53.8%) HANE patients. Nine patients had oligomenorrhoea (five with PCO, three with MFO, one with normal ovaries), five (three with PCO, two with MFO) were hirsute and only one (with MFO) had weight loss. No patient was obese. Mean plasma LH, testosterone, prolactin, cortisol and ACTH concentrations were normal, while FSH was significantly reduced and LH/FSH ratio increased. BE concentrations were significantly high in all the patients studied. Our results clearly demonstrate that women with HANE frequently have cystic ovaries (polycystic or multifollicular) in the presence of high BE concentrations.

The prevalence of HPV16DNA in normal and pathological cervical scrapes using the polymerase chain reaction.

Human papillomavirus (HPV) has been implicated in the development of cervical cancer. Newly developed molecular techniques have facilitated HPV identification and typing of cervical lesions. Several studies have suggested a strong correlation between HPV16 and intraepithelial cervical neoplasia. However, there is no agreement on this point since HPV16 is detected also in normal cervical tissue. We have amplified the L1 region of HPV16 DNA using the polymerase chain reaction (PCR) technique and analyzed the HPV16 prevalence in cytological scrapes of 201 Italian sexually active patients. One hundred twenty-four of these women had normal cytologic and colposcopic examination, while seventy-seven women had normal or abnormal cytology and a cervical lesion detectable by colposcopy. Within this latter group, 25 of 77 women (32.4%) were positive for HPV16 DNA, compared to 11 of 124 samples (8.87%) from women with normal cytology and colposcopy. The present results confirm the high efficiency of the PCR technique in detecting HPV16 DNA from cervical scrapes and suggest that this analysis should become a method of choice in clinical studies.

Functionally active complement is present in human ovarian follicular fluid and can be activated by seminal plasma.

Human ovarian preovulatory follicular fluids (FF) from 10 women were analysed for their complement contents. Functionally active complement was detected in all the fluids studied in amounts similar to those present in normal human serum. Pooled FF was challenged by seminal plasma in order to determine whether seminal plasma could activate FF complement, the pattern of such an activation and the possible consequences on the reproductive function. FF complement activation occurred during the incubation with seminal plasma with features including alternative pathway activation, factor B and C3 conversion and reduction in total haemolytic complement, as well as an inhibition by seminal plasma of the FF complement response to a new activating challenge. Possible consequences for fertilization, implantation of a fertilized ovum and local defence mechanisms against viruses and bacteria are discussed.

Influence of labor and oxytocin on in vitro leukotriene release by human fetal membranes and uterine decidua at term gestation.

OBJECTIVE: The purpose of this study was to determine whether labor and oxytocin influence in vitro leukotriene release by human fetal membranes and uterine decidua at term gestation. STUDY DESIGN: All women (N = 21) were studied in an academic clinical research environment. They were delivered either vaginally or before labor by cesarean section. Tissues were incubated with calcium ionophore A23187 alone or with calcium ionophore A23187 after preincubation with either oxytocin, BW755c, or cycloheximide. Leukotrienes in culture medium were determined by high-performance liquid chromatography. Statistical analysis was performed with analysis of variance. RESULTS: Tissues obtained after vaginal delivery released significantly higher (p less than 0.05) quantities of leukotrienes LTB4, LTD4, and delta-6-trans-LTB4 than did tissues obtained during cesarean section. Leukotriene release was stimulated by oxytocin and was inhibited by both BW755c and cycloheximide. CONCLUSION: These results suggest an activation of the arachidonate lipoxygenase pathway in these tissues during labor. Oxytocin could play a regulatory role in this process.

Three-dimensional architecture of the human myosalpinx isthmus. Scanning electron microscopy after NaOH digestion and ultrasonic microdissection.

The three-dimensional architecture of the human isthmic myosalpinx is directly visualized by means of scanning electron microscopy after removal of interstitial connective tissue through NaOH maceration and ultrasound microdissection. These investigations show that the myosalpinx is composed of irregularly running bundles of smooth muscle cells, changing their orientation within the myosalpinx and displaying longitudinal, oblique and circular directions. The muscular bundles anastomose and intermingle with other bundles running at different levels in the oviduct wall, and actually give rise to a wide and complex muscular network in which no distinct layers are readily discernible. These morphological data are consistent with the physiological findings that the transport of gametes and embryo in very early stages in the isthmic portion of the oviduct tube is the result of a discontinuous pattern of forward and backward movements.

Cytohistology, colposcopy and in situ hybridization in cervical preneoplastic lesions: a correlative study.

Formalin-fixed, paraffin-embedded cervical tissues from 106 patients which exhibited a colposcopically atypical transformation zone, were examined for the presence of HPV DNA by in situ hybridization using biotin-labeled HPV 6/11 and 16/18 DNA probes. From the comparative study between histologic, cytologic, colposcopic findings and virologic results it is confirmed that HPV 6/11 DNA is detected more frequently in the less severe lesions, whereas HPV 16/18 DNA is predominantly found in the most severe dysplastic lesions.

High amounts of beta-endorphin in peripheral blood mononuclear cells from HANE patients.

We measured peripheral blood mononuclear cells (PBMC) beta-endorphin (BE) in patients suffering from hereditary angioneurotic edema (HANE), a disease attributed to C1-esterase inhibitor (C1INH) deficiency inherited as an autosomal dominant trait. Two orders of considerations prompted us to undertake the study reported herein: the presence of elevated plasma BE concentrations in HANE and the demonstration of BE-immunoreactivity in human unstimulated peripheral blood leukocytes obtained from healthy volunteers. Our results show that patients suffering from HANE have a very high BE presence in uncultured, unstimulated PBMC and in unstimulated PBMC cultured for 48 h. At this time high BE concentrations are detected in the culture supernatants. These observations suggest that in HANE patients the same factor(s) involved in causing increased secretion and release of BE from the pituitary (and, in turn, increased plasma BE levels) can play a relevant role also in the determination of high BE presence in PBMC and BE release from the cells.

Role of microcolposcopy in the diagnostic evaluation of cervical pre-invasive lesions.

The present clinical study was undertaken to assess and compare the value of microcolposcopy and endocervical curettage in the diagnostic workup of patients with abnormal cervical lesions. Microcolposcopic findings were well correlated to histology both on directed biopsy and endocervical curettage specimens. Therefore, both microcolposcopy and endocervical curettage are useful procedures to explore the endocervical mucosa. Microcolposcopy should be mainly indicated in those cases where colposcopy has failed to show any lesion, or when colposcopy is unsatisfactory.

High-dose synthetic progestogens inhibit foam and smooth muscle cell proliferation and atherosclerotic plaque formation in aortas of rabbits fed a hypercholesterolemic diet.

Female rabbits on a hypercholesterolemic atherogenic diet were treated with high doses of the synthetic progestogens norethisterone and medroxyprogesterone acetate in order to clarify the effect and possibly some of the mechanism of action of these hormones on diet-induced atherogenesis. We employed morphometric studies to determine the surface area of the rabbit aorta occupied by and the maximum thickness of lipid plaques. Autoradiography with tritiated thymidine was performed to demonstrate the effect of the progestogens on cell proliferation, which plays a key role in atherogenesis. Medroxyprogesterone acetate-treated and, above all, norethisterone-treated animals exhibit a more marked reduction of atherosclerosis than control rabbits fed the same diet. Our results suggest that both progestogens we used inhibit the development of atherosclerosis mainly by blocking the proliferation of smooth muscle cells in the tunica media and the cell population of the plaque.

Leukotrienes in human umbilical plasma at birth.

The aim of this study was to see whether leukotrienes are present in human umbilical plasma at birth either before or after labour. Plasma concentrations of LTB4 (6.02 ng/ml) and LTD4 (6.11 ng/ml) were significantly higher (P less than 0.01) after spontaneous vaginal delivery than during elective caesarean section before labour (LTB4 = 1.96 ng/ml, LTD4 = 0.18 ng/ml). A possible involvement of leukotrienes in the biochemical and metabolic events of human labour is suggested.

ATP-content and kinetics of acrosome reaction in human spermatozoa: influence of various culture media and incubation time.

The ATP content and the kinetics of acrosome reaction of isolated human spermatozoa were investigated during an in vitro culture period of 3 hours in 3 serum-enriched media commonly adopted in IVF and GIFT procedures (Earle solution, Ham F10 and Menezo B2). The ATP concentration in spermatozoa did not change between 1 and 3 hr of incubation and no differences were seen using the three media under investigation. The percentage of acrosome reactions significantly increased during culture, to a similar extent in the three media. The results suggest that each of the three media is equally well suitable for human sperm culture in preparation of IVF and GIFT procedures.