Nino Pasetto

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.

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.

Leukotrienes in human umbilical plasma at birth

Summary. 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<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 sugges

The prevalence of hpv16 dna 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.

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.

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.

The prevalence of HPV16 DNA 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 I-IPV 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 Ll region of HPV16 DNA using the polymerase chain reaction (PCR) technique and analyzed the HPV16 prevalence in cytological scrapes of 201 Italian sexualIy 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. o 1s~ ~cad~nic prrss, IK.

Evaluation of human papillomavirus 16 and 18 in premalignant and malignant cervical lesions by the polymerase chain reaction

SummaryIntroductionSome patients with polycystic ovaries diagnosed by transvaginal ultrasound have no abnormalities of menstruation. The present study compares body mass indices, ovarian areas and androgen levels in these women with women with polycystic ovaries in combination with oligomenorrhoea.

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.