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L Cobellis

Publications and source records attributed to L Cobellis.

At least 55 records · Page 3Linked to original sources
PubMed2001

Gonadal malignant germ cell tumors express immunoreactive inhibin/activin subunits.

OBJECTIVE: Inhibin and activin are proteins produced by ovarian granulosa cells and testicular Sertoli cells and are members of the transforming growth factor-beta superfamily. Since increased circulating levels of immunoreactive inhibin were detected in women with malignant ovarian tumors, they were proposed as tumor markers for ovarian carcinoma. Immunohistochemical studies later confirmed the presence of inhibin and activin subunits in granulosa cell tumors and epithelial ovarian cancer, as well as in Sertoli and Leydig cell testicular cancer. However, there is discrepant information on the detection of inhibin and activin in malignant germ cell tumors (MGCT). The aim of the present study was to evaluate the immunohistochemical expression of the inhibin/activin alpha, betaA and betaB subunits in ovarian and testicular MGCT specimens using polyclonal antisera. METHODS: The ovarian tissue samples were composed of 19 MGCT, including dysgerminoma (n=18) and yolk sac tumor (n=1). The testis specimens included classic seminomas (n=20), embryonal carcinomas (n=7), choriocarcinomas (n=2), and yolk sac tumor (n=1). RESULTS: Ovarian and testicular malignant germ cell tumors expressed positive staining for inhibin/activin alpha, betaA and betaB subunits, with some variations between and within individual tumors: while ovarian dysgerminomas were diffusely positive for alpha, betaA and betaB, testicular tumors expressed alpha and betaB subunits, whereas betaA staining was weak. CONCLUSIONS: The present results show positive staining for inhibin/activin subunits in ovarian and testicular MGCT, suggesting a possible role in tumorigenesis with the resultant clinical implication.

Activins↗
PubMed2001

Serum activin A levels in males and females during pubertal development.

Activin A is a dimeric protein composed of two beta A-subunits protein of the transforming growth factor-beta (TGF-beta) family. This protein is synthesized by a variety of organs. A sensitive and specific assay for bioactive dimeric activin A has recently been developed, to measure circulating levels in adult women and men, giving a new insights into the possible physiological role of this protein in the reproductive axis and/or in other functions. The aim of the present study was to evaluate serum dimeric activin A levels in boys and girls during pubertal development. The study was performed on a group of children (n = 54) aged between 6 and 18 years at different Tanner stages. Serum levels of activin A were measured using a specific and sensitive two-site ELISA. Serum activin A levels were not significantly different at various Tanner stages (Tanner I, 0.36 +/- 0.02 ng/ml; Tanner II, 0.33 +/- 0.02 ng/ml; Tanner III, 0.35 +/- 0.03 ng/ml; Tanner IV, 0.41 +/- 0.04 ng/ml; Tanner V, 0.35 +/- 0.05 ng/ml; p > 0.01). No difference between male and female children was observed. In conclusion, the lack of significant differences in activin A serum levels according to the Tanner stages or to gender demonstrates that this protein is not involved in the endocrine modifications during pubertal development and that its measurement may not provide a sensitive new tool for determining gonadal maturity at puberty.

Activins↗
PubMed2001

[Ovarian function after total simple hysterectomy].

BACKGROUND: The aim of this prospective study is to evaluate the ovarian function and its duration after total simple hysterectomy. METHODS: This research was carried out on thirty regularly menstruating patients who underwent simple hysterectomy. Ovarian function has been evaluated by measuring FSH, E2, PP at 6 and 24 months from hysterectomy or from the first observation at the beginning of the study. RESULTS: None of the patients showed ovarian failure at 6 months. Nine patients (average age: 48,8 years) showed ovarian failure at 24 months. CONCLUSIONS: The conclusion is drawn that the cessation of ovarian activity is not influenced by hysterectomy: it rather depends on the age of the patient.

Adult↗
PubMed2001

[A case of atypical bicornate unicollis uterus treated with metroplasty according to Jones].

The aim of the study is to report on the result achieved on uterus bicornate unicollis that after hysterosalpingography proved atypical in the isthmic section of the left horn because it was filiform and had irregular walls. The metroplasty technique was performed, applying the Jones technique, on a patient affected by infertility for six years, with uterine malformation. Hysterosalpingography evidenced an atypical malformation: a unicollis-bicornis uterus that was atypical in the isthmic section of the left horn, treated with the technique of Jones because it was filiform. Diagnostic laparoscopy visualized two symmetrical and separated horns. Metroplasty was performed applying Jones technique, by removing the isthmic miometrium of the left horn in order to widen the communication with the upper part. The result of postoperative hysterosalpingography, performed 10 months after intervention, showed a single uterine cavity with irregular walls that allowed the evolution of a pregnancy that was prematurely concluded after thirty-two weeks on the birth of a live, vital fetus. Infertility is probably associated with the complexity of uterine malformation. We can, therefore, underline that laparotomic metroplasty is an effective technique that can be performed in particular cases.

Adult↗
PubMed2001

Regression of ovarian enlargement in pharmacological ovulation induction.

The aim of the present study was to determine a possible relationship between ovarian functionality and regression of ovarian enlargement according to the different categories and degree of severity of ovarian hyperstimulation syndrome (OHSS). Among a group of sterile woman (n = 111), two subgroups were studied: group A (n = 15), patients affected by severe syndrome; and group B (n = 96), patients with massive ovarian enlargement only. The protocol of ovarian stimulation was conducted in various in vitro fertilization (IVF) centers; ultrasonographic examination and hematological checks were carried out daily; patients with severe OHSS were hospitalized. In women of group A, severe symptoms disappeared in 7-11 days; in nine patients with regular cycles ovary size returned to normal in about 30-40 days, whereas in six subjects with anovulatory cycles, the resolution was recorded in about 50-60 days; serum estradiol returned to physiological levels within 20-30 days. Women of group B showed a spontaneous regression at different times: in 43 subjects that presented regular ovulatory cycles, the resolution was recorded in about 30-40 days, whereas in 36 women with anovulatory cycles before pharmacological induction, resolution occurred in 50-60 days, and in 17 cases with polycystic ovary syndrome before pharmacological ovulation, an incomplete resolution was obtained; serum estradiol levels returned to a physiological range within 20-30 days. Our results show that in patients with regular ovulatory cycles, resolution of symptoms is obtained in a shorter time than in patients with anovulatory cycles before pharmacological induction.

Adult↗
PubMed2001

[Cesarean section according to Stark].

BACKGROUND: The aim of this paper is to compare cesarean section according to Stark to cesarean section according to conventional technique in order to evaluate advantages and limits. METHODS PLACE: Second University of Study of Naples, Department of Obstetrics and Gynaecology, during the period from March 1996 to March 1999. PATIENTS: One hundred and two cesarean sections according to Stark were performed. These interventions have been compared with others performed, during the same period, according to the conventional technique. INTERVENTION: Comparison between cesarean section according to Stark and cesarean section according to conventional technique. RESULTS: For each case, several parameters have been compared: extraction time, total time, number of suture threads, canalization time, blood loss and fetal Apgar. CONCLUSIONS: Cesarean section according to Stark is an evolution of the conventional surgical technique, which can be applied for particular indications such as maternal, fetal and anesthesiologic conditions.

Cesarean Section↗
PubMed2000

Effects of hormone replacement therapy on postmenopausal uterine myoma.

OBJECTIVES: To evaluate the effects of sequential continuous hormone replacement therapy (HRT) on myoma size and on pulsatility index (PI) of uterine arteries and to verify the correlation between uterine artery flow impedance and the growth rate of myoma in women receiving HRT. METHODS: In a prospective 1-year study 60 postmenopausal women were enrolled into three study-groups to receive continuous transdermal 17beta-oestradiol 0.05 mg/day plus nomegestrolo acetate 5 mg/day sequentially added: 20 patients (group A) unaffected by uterine myomas, 20 patients (group B) with single asymptomatic myoma <3 cm/14 cm3, 20 patients (group C) with single asymptomatic myoma >3 cm/14 cm3. The changes in myoma volume and in PI were assessed by means of transvaginal ultrasonographic scan every 3 months. The patients with myoma were divided into two subgroups: quiescent myoma (B1, C1) and growing myoma (B2, C2). RESULTS: No significant increase of uterine fibroids volume was found after 1-year HRT (24.14+/-20.02-->28.81+/-30.02 cm3). Six out of eight myomas growing during HRT belonged to group C. The uterine artery basal PI value of group A was significantly higher (P<0.01) than the corresponding PI in group B and C. At 3 months follow-up, uterine artery PI was significantly higher (P<0.01) than the basal value in both group B (1.70+/-0.22-->1.88+/-0.16) and C (1.59+/-0.28-->1.92+/-0.21). The baseline PI values in group B1 and C1 were significantly higher than the baseline values observed in group B2 and C2 (1.76+/-0.17 vs. 1.32+/-0.02, 1.76+/-0.16 vs. 1.24+/-0.08) and significantly lower than those observed in group A (2.39+/-0.47). After 3 months of HRT, the PI values were not significantly higher than the baseline values in groups B1 and C2 (1.76+/-0.17-->1.90+/-0.17; 1.24+/-0.08-->1.74+/-0.16), while they were significantly higher in group C1 (1.76+/-0.16-->2.01+/-0.17). CONCLUSIONS: Sequential continuous HRT does not increase the volume of the uterine myoma. The findings of very low resistance index in the uterine arteries of women with growing myoma may indicate the risk of growth of the neoplasia during HRT. The assessment of PI in the uterine arteries could be helpful in predicting the growth rate of the myomas before starting HRT.

Estradiol↗
PubMed2000

Influence of non-gonadotrophic hormones on gonadal function.

Inhibins and activins are dimeric glycoproteins, member of the transforming growth factor beta (TGF beta) superfamily. The main source and targets of inhibins during the fertile age, in non pregnant women, are the ovaries, while during pregnancy placental production becomes predominant. Activin is produced from several organs: brain, ovary, uterus, placenta and spleen. During the menstrual cycles, inhibin B concentrations rise in the follicular phase with a peak after the ovulation peak of LH, inhibin A becomes predominant in the luteal phase. During reproductive life no significant change of activin A serum concentrations have been demonstrated. Inhibins and activins play an important biological role in the regulation of the HPO axis. The evaluation of inhibins and activins change is useful in understanding the pathophysiology of gynecological diseases and in the diagnosis of obstetric and gynecological pathologies.

Activins↗
PubMed2000

Activin A stimulates insulin secretion in cultured human pancreatic islets.

Activin A is a dimeric glycoprotein showing a high sequence homology with transforming growth factor-beta (TGF-beta) and playing autocrine/paracrine actions in reproductive tissues. However, since the synthesis of activin is ubiquitous it may have a role in regulating cell growth and differentiation in several tissues. Previous studies showed that activin A is expressed by insulin-positive B cells of human pancreatic islets, and women with gestational diabetes have higher serum activin A levels than healthy pregnant women at the same gestational age. The present study aimed to evaluate the effect of activin A on insulin secretion from cultured human pancreatic islets. With this purpose human pancreatic islets were incubated with varying concentrations of activin A (0.1 to 10.0 nM). In absence of glucose, activin A did not modify insulin secretion at the different concentrations used. In absence of activin A, 8.3 mM and 16.7 mM glucose significantly increased insulin secretion, with a dose-dependent pattern. In presence of a non stimulatory concentration of glucose (3.3 mM), activin A significantly increased insulin secretion starting from low concentration (0.1 nM). Furthermore, the addition of activin A to 8.3 mM and 16.7 mM glucose induced an additional effect of the dose-dependent glucose-mediated insulin secretion (p<0.001). The present data could support a role for activin A in human endocrine pancreas in modulating insulin response to different glucose concentrations.

Activins↗
PubMed2000

Criteria predicting the absence of spermatozoa in the Sertoli cell-only syndrome can be used to improve success rates of sperm retrieval.

In patients with non-obstructive azoospermia, testicular sperm extraction (TESE) is a method of choice to recover spermatozoa as a male therapeutic approach in intracytoplasmic sperm injection (ICSI) programmes. However, the efficacy of TESE in this indication is burdened by a frequent failure of sperm recovery, which renders useless both the invasive testicular intervention and ovarian stimulation of the patient's spouse. One of the most frequent pathological pictures characterizing complete absence of spermatozoa is germinal aplasia (Sertoli cell- only syndrome or SCOS). Two different histological patterns of SCOS have been already described during the past five decades. These two patterns can be characterized as the congenital (pure) and the secondary (mixed) forms. Both patterns, with different prognosis to retrieve spermatozoa by therapeutic testicular biopsy, are frequently confused when TESE is performed during ICSI programmes. Useful criteria to predict the absence of spermatozoa can be obtained by a definite recognition of the two typical histological patterns during the diagnostic testicular biopsy. The diagnosis of congenital or acquired SCOS can be refined by endocrine, chemical, immunohistochemical and molecular biology aids. Reduction of both sperm retrieval failure and unnecessary ovarian stimulation can be achieved by combination of these methods.

Forecasting↗
PubMed2000

Placental corticotropin-releasing factor. An update.

Corticotropin-releasing factor (CRF) produced in placenta has paracrine effects within placenta, decidua, and myometrium and endocrine effects on mother and fetus. CRF is a potent local regulator of myometrial contractility and of prostaglandin release, Recently, urocortin, a new member of the CRF family, has been localized in human placenta and membranes. Urocortin mimics some of the local effects of CRF in intrauterine tissues, that is, increase of adrenocorticotrophic hormone (ACTH) and prostagiandin release and myometrial contractility. A local CRF-BP modulates the paracrine effects of CRF and urocortin. The various CRF receptor subtypes are well distributed in placenta and membranes. CRH also acts on placental blood vasculature and has an action on fetal adrenal gland to stimulate the production of the steroid DHEA-S. In nonpregnant women, plasma CRF levels are low; they become higher during the first and second trimesters of pregnancy. A clear increase is evident at term and when CRF-BP levels decrease. Women with preterm labor show high CRF and low CRF-BP levels, supporting an involvement of this pathway in mechanism of parturition.

Corticotropin-Releasing Hormone↗
PubMed2000

Ovarian follicular fluid contains immunoreactive estriol: lack of correlation with estradiol concentrations.

Estradiol and estrone concentrations in ovarian follicular fluid change according to the ovulatory cycle, but no studies on the possible presence and/or changes of estriol are available. The aim of the present study was to evaluate whether estriol is measurable in follicular fluid and how its concentration changes according to the volume of ovarian follicles and to the maturational stage of oocytes. A group of women (n = 39) undergoing a program of induction of ovulation was included in this study and divided into three groups according to the causes of infertility: those with unexplained infertility (n = 11); those with endocrine disturbances (n = 5); and normal ovulatory women (n = 23) (controls). The follicles recruited (n = 116) on the basis of morphology and the appearance of the oocyte cumulus-corona complex were divided into: mature (n = 22); intermediate (n = 75); immature (n = 11); and atretic (n = 8). Ovarian follicles were also divided according to the diameter of each: < 1.5 cm (n = 38); 1.6-2.4 cm (n = 66); and > 2.5 cm (n = 12). Ovarian follicular fluids were aspirated under ultrasound guidance and a blood specimen was collected from each subject. Estriol and estradiol concentrations were evaluated by radioimmunoassay in serum and follicular fluid following an ether extraction. Estriol was found in high concentration in each sample of follicular fluid, significantly higher than in the respective serum sample (p < 0.01). Although the estradiol concentration was significantly lower in follicles containing immature and atretic oocytes than in intermediate or mature follicles (p < 0.01), the estriol concentration did not depend upon the maturational stage. In addition, the follicular fluid estriol concentration did not differ according to the causes of infertility. Follicular fluid and serum estradiol concentrations showed significant correlation (p < 0.01), whereas no significant correlation was observed between serum and follicular estriol concentrations. The present data show that follicular fluid contains a high concentration of estriol and that its changes are independent of the ovulatory cycle and estradiol concentrations, supporting an independent origin and suggesting a different function for estriol.

Estradiol↗
PubMed2000

Paracrine/autocrine control of female reproduction.

Neuropeptides, growth factors and cytokines are expressed in reproductive organs and tissues, where they interact with afferent endocrine messages to modulate cell proliferation and differentiation, local hormone secretion and vascular function. These events regulate complex processes such as gonadotropin pulsatility, ovulation, implantation and parturition. During reproductive life, a number of neuropeptides produced within the hypothalamus play a modulatory role in the control of gonadotropin-releasing hormone (GnRH) release, hence characterizing a hypothalamic paracrine system. The pituitary gland is a source and target of inhibin-related proteins, and these typical 'gonadal' products, once secreted by the pituitary cells, acquire the function of paracrine modulators of follicle-stimulating hormone (FSH) secretion. In the ovary, the effect of gonadotropins is locally modulated by growth factors acting in an autocrine/paracrine manner, although their precise role in folliculogenesis remains uncertain. Numerous local factors are involved in the control of endometrial growth, differentiation, receptivity and menstruation. Alterations in the paracrine endometrial system may underlie pathological processes such as infertility or endometrial neoplasia. The human placenta and its related membranes produce cytokines, hormones and growth factors that participate in the control of gestational development as well as in the maternal-fetal adaptation to gestational diseases. There is increasing evidence that paracrine signaling plays a fundamental role in all spheres of female reproductive function, and future research will concentrate on clarifying which of these local mechanisms play a decisive role in both physiology and disease, thus giving rise to new therapeutic strategies.

Corticotropin-Releasing Hormone↗
PubMed2000

Malignant melanoma of the vagina. A report of 15 cases.

Twenty patients affected by vaginal malignant melanoma, 15 of which were evaluable for outcome, were observed from 1969 to 1993. Two patients died postoperatively, nine patients developed recurrences and four patients had no disease-free period. All patients died of their disease and the median overall survival was 19 months. The natural history of vaginal malignant melanoma differs from that of the skin with a more aggressive behaviour. Primary treatment should be wide local excision of the tumor.

Adult↗
PubMed2000

Contribution to the choice of therapy in abdominal pregnancy.

The goal of our study was to offer our contribution to the selection of the most suitable therapy to treat abdominal pregnancy. We discuss three patients affected with this pathology, which was diagnosed early by laparoscopy. The patients were treated with 50 mg/m2 of methotrexate administered intravenously. The abdominal pregnancy was terminated in all three patients. Since the outcome involved termination of the pregnancy, it is important to emphasize that methotrexate therapy, must be considered elective. Operative laparoscopy can be limited only to cases in which the ovum has not become implanted in the intestinal interstices and is not near sites susceptible to complications.

Adult↗
PubMed2000

[Exploration of the uterine cavity in the gynecologic preoperative diagnosis].

BACKGROUND: The diagnostic accuracy of dilatation and curettage (D & C) was studied comparing retrospectively the results of histologic findings of D & C with the correspondent specimen from hysterectomy. METHODS: During five years, at the Institute of Gynecology and Obstetrics, II University of Studies in Naples, 260 women underwent hysterectomy, 160 of which underwent D & C prior to hysterectomy. The histologic findings were classified in: a) physiological endometrium; b) hyperplasia; c) polyps; d) atrophia; e) adenomatous hyperplasia; f) adenocarcinoma. During the period January 1989-October 1993, 260 patients underwent hysterectomy. The age was between 32 and 65 years. The indications to the intervention were: menometrorrhagia, hypogastric pains, dysmenorrhea, metrorrhagia, genital prolapse, urinary incontinence, anemia. Two hundred-sixty patients underwent hysterectomy, 160 of which underwent D & C prior to hysterectomy. Curettage was performed using a right size curette after dilatation of the uterine cervix using Hegar's metallic dilatator. Patients were submitted to general anesthesia. Histologic tissues were fixed with formalin and were sent to the Institute of Anatomopathology for examinations. RESULTS: The histologic results obtained by cavitary exploration have been compared with those reached by the analysis of the surgical samples. The results obtained confirm the reliability of D & C for the identification of endometrial lesions. CONCLUSIONS: Therefore, the diagnostic utility of cavitary exploration before hysterectomy is confirmed, particularly in selected cases.

Adult↗
PubMed1998

[Use of methotrexate in ectopic pregnancy. Results in 55 patients treated].

BACKGROUND: The opportunity of conservative therapeutic approaches for the treatment of ectopic pregnancy diagnosed early with the use of transvaginal ultrasound. A number of papers came out in the last 15 years, showing successful medical therapies for ectopic pregnancies using methotrexate (MTX) in particular, an analog of folic acid with particular tropism for the trophoblast. METHODS: In this retrospective study, the results of 55 consecutive cases of tubaric pregnancy, treated by endovenous administration of 50 mg/m2 MTX, are presented. RESULTS: The percent of global success was 91% (50/55 patients). A single dose of MTX was able to resolve the tubaric pregnancy in 48 women (89%), while a second administration was necessary in the other seven cases. The percent of success was complete (100%) in patients with six weeks of amenorrhea; these values drop to 72% in patients with seven-eight weeks of amenorrhea; in fact in 5 patients there was a tubal damage. CONCLUSIONS: The results obtained show the possibility to treat electively with MTX patients with ectopic pregnancy at six weeks of amenorrhea, and with good possibilities to save the tubaric patency. For patients with a longer amenorrhea the therapy with MTX remains alternative.

Adolescent↗