[Expression of oncogenes, growth factors and their receptors in follicular growth, regression and atresia: their roles in granulosa cell proliferation and differentiation]

Ovarian folliculogenesis is a dynamic and complex process during which follicles undergo tremendous growth and maturation. Beginning as a single layer of pregranulosa cells surrounding the immature oocyte, granulosa cells actively proliferate and differentiate until the time of ovulation. The proliferation of granulosa cells is necessary not only for follicular growth but also for creation of the unique micro-environment for oocyte maturation. Although the primary role of follicle-stimulating hormone (FSH) in granulosa cell growth and function is well established, detailed mechanisms regulating folliculogenesis are not understood. Thus, in this study the role of several growth factors, such as thyroid hormone, insulin, insulin-like growth factor-I (IGF-I), epidermal growth factor (EGF), transforming growth factor-beta (TGF beta) and tumor necrosis factor-alpha (TNF alpha) were evaluated for their potential as endocrine, paracrine and/or autocrine regulators of granulosa cell proliferation and differentiation. Furthermore, the granulosa cell is one of the most rapidly growing normal cell types known, so a possible participation of the myc oncogene in granulosa cell proliferation was assumed. Actually, we have found that myc oncoprotein is expressed in granulosa cells in a stage-limited manner during follicular growth and regression. Abundant expression of myc oncoprotein in granulosa cells was apparent only at the preantral follicle stage. Moreover, c-myc mRNA was expressed abundantly only in the granulosa cells of the less-mature, small follicles. The stage-specific expression of c-myc oncogene in immature granulosa cells early in follicular growth may suggest the intriguing possibility of c-myc oncogene participation in the autonomous growth of the immature follicles during the early stage of folliculogenesis. We have also shown that erb-A oncogene, which encodes a thyroid hormone receptor, was expressed more abundantly in small-follicle granulosa cells than in large-follicle granulosa cells. Thus, it is possible that the expression of these oncogenes, either alone or in combination, may play a role in autonomous granulosa cell proliferation early in follicular development. On the other hand, thyroid hormone, insulin, IGF-I and EGF were found to be act as biological amplifiers (up-regulators) of FSH actions in granulosa cells, whereas TGF beta and TNF alpha were shown to act as down-regulators of FSH actions in granulosa cells. Greater than 99% of ovarian follicles undergo atresia during reproductive life. It has been shown that apoptotic cell death is the molecular mechanism underlying follicle atresia.(ABSTRACT TRUNCATED AT 400 WORDS)

[Botulinum toxin type A (BOTOX) for treatment of blepharospasm: an open label, dose-response study]

The clinical effect of Botulinum Toxin Type A (BOTOX) were studied in patients with blepharospasm. Clinical symptoms were evaluated with Jankovic's rating scale, widely used for blepharospasm. To see dose response, eyelid muscle force of the patients was measured with a device recently developed for measurement of eyelid muscle force. The results showed significant improvement (p = 0.0000) on Jankovic's rating scale in all patient groups after effective dose injections of 0.5, 1.25, and 2.5 U/site. Particularly the number of patients with marked improvement (decrease of six points or more in total score on Jankovic's rating scale) increased with higher dose injections. The eyelid muscle force also decreased by 33.2 +/- 28.1%, 41.7 +/- 25.1%, and 69.6 +/- 5.0% in patients groups after effective dose injections of 0.5, 1.25, and 2.5 U/site, respectively. The decrease of the eyelid muscle force showed significant dose response (p = 0.0254). Mean duration of effect was 12.9 weeks in patients after effective dose injections of 1.25 U/site, which was significantly longer (p = 0.0205) than that of 9.6 weeks in patients after effective dose injections of 0.5 U/site. No severe adverse effects were observed. We concluded that BOTOX injections of 1.25 U/site or more are a safe and effective treatment of blepharospasm.

Modulatory effects of neurohypophysary origin hormones on placental hormone secretion at term

Oxytocin (OT) and arginine-vasopressin (AVP) are two major neurohypophysary nonapeptides that have impor-tant roles during pregnancy and labor. Using the expiant model at term, we have examined the effect of physiologic concentrations of both nonapeptides on placental hormone secretion. We found that OT had a dose-dependent inhibitory effect on P (2-3-fold.P<0.05) and hCG (2-fold,P<0.05) while increasing E(2) secretion (150-180%,P<0.05) into the media. The effect of OT on P secretion was receptor-dependent since it was abolished by addition of CAP-450 into the media. AVP increased E(2) secretion up to 2-fold. <0.05) while not having a consistent effect on P secretion. In conclusion, OT and to a lesser degree AVP, have significant modulatory effects on placental hormone secretion. Whether the resulting locally increased E(2)/P secretion ratio favors progression of labor remains to be shown.

[Quantitative analysis of electromyogram interference pattern in extraocular muscle]

Quantitative analysis of electromyogram (EMG) interference pattern was performed for objective evaluation. EMGs of 261 horizontal rectus muscles had been recorded in our laboratory during the past 18 years, and they were divided according to the clinical diagnosis into four categories: 56 records due to complete neuropathy, 67 due to incomplete neuropathy, 19 due to myopathy, and 119 normal. The turns and amplitude analysis program was used for EMG analysis. A turn was one wave of the interference pattern, for which we used an amplitude of more than 15 microV. Turns meant the number of turn waves per second. Turns/second and mean amplitude/turn (A/T) were plotted against each other on an X-Y diagram, and a statistical evaluation of data was done. Complete neuropathy recordings that had lower turns and lower A/T were separated from the other three categories. Incomplete neuropathy and myopathy occurred on the lower A/T area. There was a significant difference (p < 0.05) between each pair of comparisons from all four categories except for turns evaluated between myopathy and normal. Quantitative analysis proved useful for the objective evaluation of the EMG interference pattern, particularly between cases of complete and incomplete neuropathy.

Insulin-like growth factor-I as a local regulator of proliferation and differentiated function of the human trophoblast in early pregnancy

In order to elucidate the role of insulin-like growth factor-I (IGF-I) in human placental growth and function, the effects of IGF-I on the proliferation and differentiation of trophoblasts were investigated using an organ culture system of early placental tissues. Explants of trophoblastic tissues obtained from 4-5-week or 6-12-week placentae were, respectively, cultured with or without IGF-I, in a serum-free condition. The effect of IGF-I on the proliferative activity of trophoblasts was examined by immunocytochemical techniques with a monoclonal antibody to proliferating cell nuclear antigen (PCNA), while the effect of IGF-I on the differentiated function of trophoblasts was assessed by determining the ability to secrete human chorionic gonadotropin (hCG) and human placental lactogen (hPL). In 4-5-week placentae, IGF-I and IGF-I receptor were almost exclusively localized in cytotrophoblasts and IGF-I augmented the proliferative activity of cytotrophoblasts without affecting the ability to secrete hCG and hPL. By contrast, in 6-12-week placentae, IGF-I and IGF-I receptor were localized in both cytotrophoblasts and syncytiotrophoblasts and IGF-I stimulated the secretion of hCG and hPL following the enhancement of the proliferative activity of trophoblasts. In column chromatography of the serum-free medium obtained following 5-day culture of early placental tissues, an elution peak of immunoreactive IGF-I was found in the fractions similar to the elution region of [125I]IGF-I. These findings suggest that IGF-I acts as an autocrine/paracrine factor in regulating early placental growth and function.

[Effects of estrogen and thyroid hormone on EGF receptor expression, proliferative activity and SCC production in the CaSki cervical carcinoma cells]

This study was undertaken to see if estrogen and thyroid hormone affected EGF-receptor (EGF-R) expression, proliferative activity and intracellular SCC levels in uterine cervical squamous carcinoma cells. The uterine cervical cancer cell line (CaSki) was cultured in vitro in the absence or presence of 17 beta-estradiol (E2) or L-triiodothyronine (T3) in a serum free condition. Effects of E2 or T3 on the characteristics of EGF-R were assessed by the Scatchard analysis of the binding assay with 125I-EGF. Cellular levels of EGF-R expression were examined by the immunoperoxidase method with a monoclonal antibody to EGF-R. Proliferative activity of the cells was determined by proliferating cell nuclear antigen (PCNA) immunostaining, 3H-thymidine uptake and the number of cells. The effects of E2 or T3 on intracellular SCC levels were also examined by determining the intracellular SCC concentration with an SCC-RIA Kit. The scatchard analysis of 125I-EGF binding to CaSki cells showed that the addition of E2 or T3 had little effect on the affinity of EGF-R for CaSki cells but increased the capacity of EGF-R for the cells. Immunocytochemical staining with anti EGF-R antibody demonstrated that EGF-R expression in the CaSki cells was augmented by the addition of E2 or T3. The addition of E2 or T3 also resulted in an increase in 3H-thymidine uptake by the CaSki cells, the PCNA positive rate and the number of cells. Furthermore the addition of E2 or T3 increased intracellular SCC in the CaSki cells.(ABSTRACT TRUNCATED AT 250 WORDS)

[Preoperative prediction of the amount of surgical correction by using Botulinum A type toxin for the treatment of paralytic esotropia]

The aim of this study was to obtain the correct choice of initial surgical procedure and to predict the amount of surgical correction by using the maximum reduction rate of eye position after Botulinum A-type toxin injection for the treatment of acquired neurogenic paralytic strabismus. The subjects were 30 with sixth nerve palsy and 33 with non-paralytic esotopia with no previous surgery. The results were that if the maximum reduction rate of eye position after the first injection of 1.25 U was less than 68%, the modified Jensen procedure with recession of medial rectus muscle was necessary to achieve 100% recovery. However, if it was more than 100%, then recession-resection of the horizontal rectus muscles alone produced successful ocular alignment. Based on our data of 100 cases of sixth nerve palsy that showed spontaneous recovery, we conclude that surgical treatment should be planned, if the maximum percentage reduction of preoperative eye position after Botulinum A-type toxin treatment is under 68% (reflecting the inability of the medial rectus muscle to contract and the lengthening of the lateral rectus muscle), and if the patient has no spontaneous improvement at all within 12 weeks after onset.

Role of epidermal growth factor (EGF) and its receptor in the development of the human placenta

To elucidate the role of EGF in human placental development, effects of EGF on the proliferation and differentiation of trophoblasts were investigated. Explants of trophoblastic tissues obtained from 4-5 week or 6-12 week placentas were, respectively, cultured with or without EGF, in the presence or absence of triiodo-L-thyronine (T3) in a serum-free condition. The proliferative activity was examined by immunocytochemical staining with an antibody Ki-67, and the differentiated function was assessed by the ability to secrete human chorionic gonadotrophin (hCG) and human placental lactogen (hPL). In 4-5 week placentas, EGF and EGF receptor were localized in cytotrophoblast (C-cell), and EGF augmented the proliferation of C-cell without affecting the ability to secrete hCG and hPL. In contrast, in 6-12 week placentas, EGF and EGF receptor were localized in syncytiotrophoblast (S-cell), and EGF stimulated the secretion of hCG and hPL without affecting the proliferation of C-cell. In situ hybridization with c-erb B probe revealed that c-erb B mRNA is expressed in the S-cell after 6 weeks' gestation. Column chromatography of the serum-free media obtained by 5-day culture of early placental tissues resulted in the elution of immunoreactive EGF. The addition of T3 (10(-8) mol L(-1)) resulted in increased secretion of immunoreactive EGF by placental explants. These findings suggest that EGF acts as an autocrine factor in regulating early placental growth and function in synergy with thyroid hormone.

Expression of transforming growth factor-alpha in the human ovary during follicular growth, regression and atresia

The cytologic localization and cellular levels of TGF alpha in the human ovary during follicular growth and regression were examined by avidin/biotin immunoperoxidase techniques with a monoclonal antibody to TGF alpha. In primordial follicles, only the oocyte showed intense immunostaining for TGF alpha, whereas the flattened pregranulosa cells were negative for the immunostaining. The earliest stage of follicular growth at which immunostaining for TGF alpha in granulosa cells and theca interna cells became apparent was the preantral stage. With the increase in the size of follicles, the intensity of TGF alpha immunostaining in the oocyte decreased, whereas the staining intensity of the granulosa and theca cells increased. The immunostaining for TGF alpha in granulosa and theca interna cells persisted in the corpus luteum, and further intensified during the midluteal phase. In the regressing corpus luteum, the immunostaining was present only in the peripheral theca lutein cells adjacent to the central scar tissue. The corpus albicans was negative for the immunostaining. Stromal cells exhibited weak staining for TGF alpha. In atretic follicles, the theca interna cells exhibited intense staining for TGF alpha without appreciable staining in the scattered granulosa cells. This is the first report to demonstrate that TGF alpha expression in the oocyte is maximal in primordial follicles, whereas TGF alpha expression in granulosa and theca cells increases with the progress of follicles and reaches its maximum in the lutein cells during the mid luteal phase.(ABSTRACT TRUNCATED AT 250 WORDS)

[Treatment of paralytic strabismus]

1) Cases of strabismus combined with abnormalities in ocular movement were divided into three groups: paralytic nonconcomitant strabismus, special forms of strabismus, and paralytic concomitant strabismus. 977 cases of surgery for paralytic nonconcomitant strabismus were analyzed. 2) 109 cases of surgery for paralytic esotropia due to abducens palsy were performed. In cases of complete paralysis, a transposition of the vertical rectus muscle was indicated. In cases of incomplete paralysis, a resection of the lateral rectus muscle was indicated. On the basis of these indications, the same results could be achieved, and when a recession of the medial rectus muscle was concurrently performed the results were improved. 3) In oculomotor palsy, 138 cases of surgery for paralytic exotropia were performed. In cases of complete paralysis, a transposition of the superior oblique muscle was indicated. In cases of incomplete paralysis, a resection of the medial rectus muscle was indicated. On the basis of these indications, the same results could be achieved, and when a recession of the lateral rectus muscle was concurrently performed the results were improved. 4) 570 cases of surgery for superior oblique muscle palsy were performed. In cases of vertical deviation, a weakening operation on the inferior oblique muscle, the superior rectus muscle of the affected eye, and the inferior rectus muscle of the sound eye were indicated. In cases of torsional deviation, good results were obtained through an advancement of the anterior part of the superior oblique muscle and a resection of the superior oblique muscle. 5) Statistics concerning cure based on the standards for cure employed by the Japanese Association of Strabismus and Amblyopia, or from the point of view of cosmetic cure were: 85% for paralytic esotropia and superior oblique muscle palsy, 82% satisfactory for incomplete paralysis of the oculomotor nerve within paralytic exotropia, and 61% relatively unsatisfactory for complete paralysis of the oculomotor nerve within paralytic exotropia. 6) The results of 216 cases examined after period of four years or longer were: cases where a one-month postoperative cure or cosmetic cure was maintained over this period were 90% of superior oblique muscle palsy cases, 79% of paralytic esotropia, and 59% of paralytic exotropia. Paralytic exotropia showed poor results. The surgical methods were muscle transposition in cases of horizontal muscle surgery and surgery of the oblique muscles in cases of vertical muscle surgery. 7) Through the Turn-Amplitude Analysis of the amounts of EMG interference patterns in the extraocular muscle, neuropathy was classified as either complete or incomplete.(ABSTRACT TRUNCATED AT 400 WORDS)

Stage-specific expression of c-myc messenger ribonucleic acid in porcine granulosa cells early in follicular growth

In the present study, the expression of c-myc mRNA in porcine granulosa cells harvested from varying follicle stages was analyzed using northern blot hybridization with a c-myc probe, and compared during follicular growth. Northern blot analysis revealed that porcine granulosa cell RNA obtained from small (1-2 mm) follicles contained an abundance of c-myc transcript of 2.4 kb, the size of which was identical to the c-myc transcript obtained with human early placental RNA used as the control. In contrast to small-follicle granulosa cell RNA, total RNA preparations from either medium (3-5 mm)-follicle granulosa cells or large (6-11 mm)-follicle granulosa cells exhibited no detectable transcripts with the c-myc probe. These results suggest that expression of c-myc mRNA in porcine granulosa cells is limited only at the early stage of follicular growth. The stage-specific expression of c-myc mRNA in granulosa cells early in follicular growth may play a physiological role in the autonomous growth of immature granulosa cells in early folliculogenesis, seemingly independent of pituitary gonadotropic stimulation.

Gestational-age-dependent effects of retinoids on HCG secretion by placental explants

Vitamin A (VITA) is considered to be an essential nutrient in both pregnant and non-pregnant states. It has been suggested that VITA, among others, is involved in the process of morphogenesis. In contrast, synthetic derivatives of VITA, specifically Tigasone (etretinate, TIG) and Roaccutane (isotretinoin, ROA), are regarded as major teratogens. Therefore, in the present study we have examined the effect of VITA and other retinoids on human chorionic gonadotrophin (HCG) secretion by placental explants in the first trimester. Results show that, at 7-9 gestational weeks, all three compounds had a significant inhibitory effect on HCG secretion. In the case of VITA, this inhibition was time-dependent. A biphasic maximal inhibition was present at 1 microM concentrations when the retinoids VITA, TIG and ROA were added for 16 h (52, 58 and 57%, respectively; P < 0.01 by one-way analysis of variance). In contrast, the addition of the three retinoids at 1 microM concentrations for 16 h had no significant effect on HCG secretion by placental explants of 11-13 weeks gestational age. In conclusion, both natural and synthetic retinoids demonstrate a significant inhibitory effect on HCG secretion by the early placenta (pre-HCG peak). VITA may be involved in causing a plateau and the later decline in HCG secretion. Inhibition of HCG secretion by retinoids may contribute either directly or indirectly to their teratogenicity.

Comparative assessment of the effects of subdermal levonorgestrel implant system and long acting progestogen injection method on lipid metabolism

In order to compare the effects of two type of long-acting progestogen contraceptive methods with subdermal levonorgestrel (LNG) implants and depot-medroxyprogesterone acetate (DMPA) injections on lipid metabolism, a clinical cohort study was performed by requiring 25 women in each group adopting either LNG implant or DMPA injection method voluntarily. After 6 months of use, serum levels of triglycerides, total cholesterol, HDL-cholesterol and LDL-cholesterol were determined and compared between the two groups of acceptors. The mean of total cholesterol in LNG implant acceptors was significantly lower than that in DMPA injection acceptors. The mean values of HDL-cholesterol in LNG implant acceptors (41.7 +/- 7.7 mg/dl) and in DMPA injection acceptors (45.0 +/- 9.0 mg/dl) were in the normal range without significant difference between the two groups. The mean value of triglycerides did not differ significantly between LNG implant acceptors (77.6 +/- 25.1 mg/dl) and DMPA injection acceptors (91.0 +/- 30.3 mg/dl). Serum concentrations of lipid fractions such as HDL-cholesterol and LDL-cholesterol in LNG implant acceptors were relatively low compared to those in DMPA injection acceptors. Since there was a comparable reduction in both total-and HDL-cholesterol levels in the LNG implant group, the ratio of total-to HDL-cholesterol, which is thought to be a factor in determining the risk of coronary artery disease, remained in the normal range (2 +/- 4.5). This suggests that the use of these two contraceptive methods with progestogens does not alter the risk of development of coronary artery disease.

[Insulin-like growth factor-I (IGF-I) as a local regulator of proliferation and differentiation of villous trophoblasts in early pregnancy]

In order to elucidate the role of insulin-like growth factor-I (IGF-I) in human placental growth and function, the effects of IGF-I on the proliferation and differentiation of villous trophoblasts were investigated in vitro using an organ culture system of human early placental tissues. Explants of trophoblastic tissues obtained from 4-5 week and 6-12 week placentas were cultured with or without IGF-I (1 ng/ml, 100 ng/ml), in the presence or absence of 10(-8) M triiodo-L-thyronine (T3) respectively, in a serum-free condition. The possible effect IGF-I on the proliferative activity of the cells was examined by immunocytochemical techniques with a monoclonal antibody to proliferating cell nuclear antigen (PCNA), while the possible effect of IGF-I on the differentiated function was assessed by determining the ability to secrete hCG and hPL. In the 4-5 week placentas, IGF-I and IGF-I receptor were almost exclusively localized in cytotrophoblasts and IGF-I augmented the proliferative activity of cytotrophoblasts without affecting the ability to secrete hCG and hPL. By contrast, in the 6-12 week placentas, IGF-I and IGF-I receptor were localized in both cytotrophoblasts and syncytiotrophoblasts and IGF-I stimulated the secretion of hCG and hPL following the enhancement of the proliferative activity of cytotrophoblasts. In column chromatography of the serum-free medium obtained following a 5-day culture of trophoblasts, an elution peak of immunoreactive IGF-I was found in the fractions similar to the elution of 125I-IGF-I. The eluted amount of immunoreactive IGF-I was increased by the addition of 10(-8) MT3 to the medium.(ABSTRACT TRUNCATED AT 250 WORDS)

Stage-limited expression of myc oncoprotein in the human ovary during follicular growth, regression and atresia

The cytologic localization and cellular levels of myc oncoprotein in the human ovary during follicular growth, regression and atresia were examined by the avidin/biotin immunoperoxidase method with a specific antibody to myc oncoprotein. In primordial follicles, only the oocyte showed intense immunostaining for myc protein, whereas the granulosa cells were negative for the staining. In preantral follicles, both the oocyte and granulosa cells were moderately immunostained for myc protein. In antral and preovulatory follicles, there was no appreciable staining for myc protein in the granulosa or theca cells, while myc protein staining in the oocyte persisted with less intensity. It is of interest that myc protein expression in granulosa cells was apparent only during the preantral follicle stage. Corpora lutea during the early and mid luteal phase were negative for myc protein staining, whereas in regressing corpora lutea during the late luteal phase, peripheral theca lutein cells adjacent to the central core of scar tissue were immunostained for myc protein. Corpora albicans showed no staining for myc protein. In atretic follicles, granulosa cells and theca interna cells demonstrated positive staining for myc protein. Ovarian stromal cells were negative for the immunostaining throughout the menstrual cycle. This demonstrates that myc protein is expressed in a stage-limited manner in the human ovary during follicular growth and regression. The abundant expression of myc protein in the oocyte at the primordial and preantral follicle stages and in the granulosa cells at the preantral follicle stage suggests a role for myc expression in the initial growth of the oocyte as well as in the autonomous growth of granulosa cells during the preantral stage seemingly independent of gonadotropic stimulation. Furthermore, notable expression of myc protein in the granulosa cells and theca interna cells of atretic follicles and in the peripheral theca lutein cells of regressing corpora lutea implies the possible participation of myc expression in remodelling the ovarian local tissue following atresia and luteolysis in the human ovary.

Insulin receptor expression in follicular and stromal compartments of the human ovary over the course of follicular growth, regression and atresia

The cytologic localization and cellular levels of insulin receptors in the human ovary during follicular growth, regression and atresia were examined by the avidin/biotin immunoperoxidase techniques with a monoclonal antibody to insulin receptor. In primordial follicles, only the oocyte showed a weak immunostaining for insulin receptor, whereas the stromal cells surrounding primordial follicles were moderately immunostained. The earliest stage of follicular growth at which immunostaining for insulin receptor in granulosa cells and theca interna cells became apparent was the preantral stage. With the increase in the size of the follicles, the immunostaining of the oocyte and follicular elements intensified, whereas the staining intensity of the stromal cells surrounding growing follicles was reduced compared to those surrounding primordial follicles. The immunostaining in granulosa and theca interna cells persisted in the corpus luteum, and further intensified during the midluteal phase. In the regressing corpus luteum, the immunostaining was present only in the peripheral lutein cells adjacent to the central scar tissue. The corpus albicans was negative for the immunostaining, but the surrounding stromal cells exhibited predominant staining. In atretic follicles, the theca interna cells exhibited intense staining for insulin receptor without appreciable staining in the scattered granulosa cells, whereas the surrounding stromal cells were moderately immunostained. This is the first study to demonstrate notable changes in insulin receptor expression in the oocyte, granulosa cells, theca cells, lutein cells and surrounding stromal cells during follicular growth, regression and atresia. The results obtained indicate insulin participation in oocyte maturation, follicular growth and stromal cell function. The increased expression of insulin receptors in theca interna cells of atretic follicles and in stromal cells surrounding the corpora albicans raises the intriguing possibility of insulin involvement in the transformation of theca interna cells into stromal cells. This implies that insulin may participate in remodelling ovarian local tissues following follicular atresia and luteolysis in the human ovary.

Altered expression of insulin and insulin-like growth factor-I receptors in follicular and stromal compartments of polycystic ovaries

In the ovary, insulin and insulin-like growth factor-I (IGF-I) act synergistically with FSH to augment estrogen production by granulosa cells and with LH to augment androgen production by thecal stromal cells. It is also evident that insulin resistance is common in patients with polycystic ovary syndrome (PCO). Thus, in the present study we investigated the expression of insulin and IGF-I receptors in PCO ovaries and compared them with those in normal ovaries. Ovarian tissues were obtained from four PCO patients undergoing wedge resection, and from six patients who underwent radical hysterectomy. Immunohistochemical staining for insulin and IGF-I receptors was performed by avidin/biotin immunoperoxidase techniques. In normal ovaries, the expression of insulin and IGF-I receptors in follicular compartment became apparent in the preantral follicle stage and augmented with the follicular growth, while the stromal cells, regardless of the follicle stage, possessed insulin and IGF-I receptors. In PCO ovaries associated with hyperinsulinemia, no expression of insulin receptors was detected in granulosa or thecal stromal cells, while IGF-I receptor expression increased in thecal stromal cells but decreased in granulosa cells compared to those in normal ovaries. However, in PCO ovaries from patients without hyperinsulinemia, insulin receptor expression was apparent in both granulosa and thecal stromal cells, with a similar intensity to that observed in normal ovaries, while IGF-I receptor expression was negligible in granulosa cells but sustained in thecal stromal cells. These findings suggest that decreased expression of insulin receptors in PCO ovaries associated with hyperinsulinemia may be secondary to receptor down regulation, whereas defective expression in granulosa cells along with elevated or persisted expression in thecal stromal cells of IGF-I receptors may be common in PCO ovaries and contribute to the endocrine profiles of PCO in which varying degrees of hyperandrogenism is a predominant feature.

Decreased expression of epidermal growth factor and its receptor in the malignant transformation of trophoblasts

BACKGROUND

Gestational trophoblastic neoplasms comprise the neoplastic spectrum of nonmalignant hydatidiform mole, invasive hydatidiform mole, and truly malignant choriocarcinoma. Increasing evidence indicates that epidermal growth factor (EGF) acts as an enhancer of trophoblast function to produce human chorionic gonadotropin and that EGF and its receptor may provide a growth advantage to certain carcinoma cells. The current study was undertaken to evaluate a possible link between malignant transformation of trophoblast and expression of EGF and EGF receptor.

METHODS

Cytologic localization and cellular levels of expression of EGF and EGF receptor in hydatidiform mole, invasive hydatidiform mole, and choriocarcinoma tissue specimens were examined by the avidin-biotin immunoperoxidase techniques with monoclonal antibodies against EGF and EGF receptor.

RESULTS

EGF in hydatidiform mole and invasive mole was localized in syncytiotrophoblasts, whereas cytologic localization of EGF receptor in hydatidiform mole and invasive mole was observed in both cytotrophoblasts and syncytiotrophoblasts. By contrast, EGF and EGF receptor in choriocarcinoma were exhibited in cytotrophoblastic and syncytiotrophoblastic elements. Most (72%) hydatidiform moles immunostained intensely for EGF and EGF receptor, whereas most (78%) choriocarcinomas immunostained slightly for EGF and EGF receptor. Invasive mole occupied the middle position in the staining intensity for EGF and EGF receptor, between hydatidiform mole and choriocarcinoma, with 50% of the cases exhibiting moderate staining.

CONCLUSIONS

The simultaneous expression of EGF and EGF receptor in the neoplastic trophoblasts implies that EGF may act in an autocrine-paracrine manner in trophoblastic neoplasms. Furthermore, the results obtained suggest that cytologic expression of EGF and EGF receptor in trophoblastic neoplasms decreases in the malignant transformation of trophoblast.

Human early placental trophoblasts produce an epidermal growth factor-like substance in synergy with thyroid hormone

Previous studies have shown that human trophoblast is the site of epidermal growth factor (EGF) localization, reception and action and that thyroid hormone exerts similar effects on trophoblasts endocrine function as observed with EGF. Thus, the present study was designed to examine local production of an EGF-like substance in synergy with thyroid hormone by early placenta. Explants of normal early (7-8 weeks) placentas were cultured in a serum-free condition in the presence or absence of L-triiodothyronine (T3), with or without cycloheximide for 4 days. The conditioned media were dialyzed, lyophilized, acidified and chromatographed over a Sephadex G-75 column equilibrated with 1 mol/l acetic acid. EGF was measured by a specific RIA for human EGF. Fractionation of the serum-free conditioned media resulted in the elution of immunoreactive EGF with an apparent molecular weight of 9,000 which is larger than [125I] human EGF. The addition of T3 (10(-8) mol/l) resulted in increased secretion of immunoreactive EGF by placental explants. By contrast, the addition of cycloheximide (5 x 10(-5) mol/l) dramatically reduced the secretion of immunoreactive EGF. The similarity of the immunoreactive EGF material to authentic human EGF was supported by parallel displacement in human EGF-RIA. These results suggest that human early placental trophoblast is capable of producing an EGF-like substance and that thyroid hormone enhances the local production of the EGF-like substance. This suggests that an autocrine/paracrine control system, wherein EGF serves as the signal in regulating placental growth and function in synergy with thyroid hormone, exists in human early placenta.

Return of fertility after the removal of intrauterine devices: a comparison of inert and copper bearing devices

The use of intrauterine device (IUD) has been suspected to be linked to involuntary infertility due to increased risk of pelvic inflammatory diseases. Nevertheless, it remains unclear whether the overall risk of infertility after discontinuing use of IUD increases with the duration of IUD use. Thus, the present study was designed to evaluate the return of fertility after discontinuing use of copper containing IUDs compared to inert IUD and to determine a possible relationship between the length of IUD use and return of fertility. Ninety women with Lippes Loop type D (LL), 88 women with Copper-T200 (TCu-200) and 83 women with Multiload Copper-250 (MLCu-250) were included in the analysis. The life table analysis and log rank-test showed that TCu-200 and MLCu-250 acceptors had a more rapid return of fertility compared to LL acceptors, although there was no significant difference in the return of fertility between TCu-200 and MLCu-250 acceptors. Compared to LL acceptors, the net cumulative probability of pregnancy after discontinuing use of IUD was 3 times higher in copper containing IUD acceptors in the first 3 months and somewhat higher in the first 4 to 11 months after removal of IUD. The length of use in copper containing IUDs (TCu-200 and MLCu-250) acceptors did not influence the return of fertility, whereas the return of fertility after removal of inert IUD (LL) was significantly higher in case of the use for shorter than 48 months compared to the use for longer than 48 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of epidermal growth factor and its receptor in the human ovary during follicular growth and regression

Immunohistochemical studies were performed using specific antibodies to epidermal growth factor (EGF) and EGF receptor to determine their presence and cellular localization in the human ovary during follicular growth and regression. There was no immunostaining for EGF or EGF receptor in primordial follicles. In the preantral follicle stage, immunostaining for EGF and EGF receptor was observed only in the oocyte. The staining intensity of the oocyte increased as the oocyte reached the preovulatory stage. In the antral follicle stage, immunostaining for EGF and EGF receptor became apparent in the granulosa and theca interna cell layers, without appreciable staining in the surrounding stromal cells. The immunostaining for EGF and EGF receptor in the granulosa cells and theca interna cells persisted in preovulatory follicles and corpus luteum, and intensified in the midluteal phase. The stromal cells surrounding the corpus luteum were negative for EGF and EGF receptor staining. In the regressing corpus luteum, immunostaining for EGF and EGF receptor was present in the peripheral lutein cells adjacent to the central core of scar tissue, but absent in the scar tissue of the central core. Corpus albicans showed no staining for EGF and EGF receptor. By contrast, the stromal cells surrounding the corpus albicans in the cortex region demonstrated intense staining for EGF and EGF receptor, while the stromal cells surrounding the corpus albicans in the medullary region were negative for immunostaining. In the case of atretic follicles, the theca interna cells showed intense staining for EGF and EGF receptor, but immunostaining in the scattered granulosa cells was negligible. This is the first study to demonstrate a remarkable change in the expression of EGF and EGF receptor in the oocyte, granulosa cells, thecal cells, and surrounding stromal cells over the course of follicular growth and regression. The results obtained support EGF participation in oocyte maturation and in follicular growth and atresia. The intense immunostaining for EGF and EGF receptor observed in the theca interna cells in atretic follicles and the stromal cells surrounding corpus albicans in the cortex region raises the possibility of EGF involvement in transformation of thecal cells into stromal cells. Furthermore, the cell type-specific simultaneous expression of EGF and EGF receptor in follicular and stromal compartments in the various stages of follicular development suggests that an autocrine mode of EGF action may exist to regulate follicular growth and regression in the human ovary.

[Epidermal growth factor regulates trophoblast proliferation and differentiation in an autocrine/paracrine manner]

Effects of epidermal growth factor (EGF) on the expression of trophoblast proliferation and differentiation were investigated in vitro using an organ culture system of human placental tissues. Explants of trophoblastic tissues obtained from each trimester of gestation were cultured with or without EGF (100 ng/ml) in serum-free conditions. In order to determine the possible effect of EGF on the proliferation activity of villous trophoblasts, immunostaining with monoclonal antibody Ki-67 was used. On the other hand, the possible effect of EGF on the differentiated cellular function of villous trophoblasts was assessed by determining the ability to secrete hCG and hPL. In 4-5 week placenta, EGF and EGF receptor were found to be almost exclusively localized in cytotrophoblasts and EGF enhanced the proliferation of cytotrophoblasts without affecting the ability to secrete hCG and hPL, whereas in 6-12 week placenta, EGF and EGF receptor were predominantly localized in syncytiotrophoblasts and EGF stimulated the secretion of hCG and hPL without affecting the proliferation of cytotrophoblasts. These findings suggest that EGF has dual actions which independently affect trophoblast proliferation and differentiation in the first trimester of gestation in an autocrine manner. But, in the second and third trimesters of gestation, EGF mediates the expression of placental function in a paracrine manner.

Gestational age-dependent dual action of epidermal growth factor on human placenta early in gestation

In order to better understand the role of epidermal growth factor (EGF) in the regulation of placental growth and function, effects of EGF on proliferative activity and differentiated function of trophoblast were examined. Explants from very early (4-5 week) placentas and early (6-7 week, 8-9 week, 10-12 week) placentas were respectively cultured under a serum-free condition in the absence or presence of EGF (100 micrograms/L) for the first 48 h, and the cultures were continued for subsequent 72 h without EGF. The proliferative potential and differentiated function of trophoblast were assessed by immunohistochemical Ki-67 staining and by determining the ability to secrete human CG (hCG) and human placental lactogen (hPL), respectively. Quantitative estimates of proliferative activity based on mean percentage of Ki-67 positive nuclei showed that EGF stimulated proliferative potential of cytotrophoblast in very early (4-5 week) placental explants. The EGF stimulation of trophoblast proliferation was apparent at a 12-h EGF-treated period. By contrast, early (6-12 week) placental explants did not respond to EGF with increase in trophoblast proliferation. Instead, in early placental explant culture EGF stimulated hCG and hPL secretion with a lag period of 72 h, whereas very early placental explants did not respond to EGF with increase in hCG and hPL secretion. These results suggest that EGF exerts gestational age-dependent dual action on the first-trimester placenta: one is to stimulate trophoblast proliferation in 4-5 week placenta and the other is to stimulate differentiated trophoblast function in 6-12 week placenta.

[Biology of trophoblast and its endocrinological profiles]

The trophoblast of human placenta is composed of syncytiotrophoblast (S-cell) and cytotrophoblast (C-cell). C-cell displays proliferative properties, while S-cell displays little potential for proliferation. A close similarity between cytologic localization of myc product and [3H]thymidine labeling suggests that myc expression is linked to trophoblast proliferation. In situ hybridization with cDNA probes revealed that mRNA expression of hCG alpha and hCG beta are initiated before syncytial formation, whereas hPL mRNA is expressed only in fully differentiated S-cell. EGF and EGF receptor (EGF-R) in 4-5 weeks placenta were localized to C-cell, whereas EGF and EGF-R in 6-12 weeks placenta were localized to S-cell. Consistent with these findings, EGF exerted gestational age dependent dual action on early placenta: one was to stimulate trophoblast proliferation in 4-5 weeks placenta and the other was to stimulate differentiated trophoblast function in 6-12 weeks placenta. An optimal dose of thyroid hormone stimulated progesterone, estradiol, hCG and hPL production in early placental tissues. Furthermore, women with unfavorable outcome of threatened abortion had lower T4, T3, free T4 and free T3 levels, as compared to women with favorable outcome. These data imply a role for thyroid hormone in maintaining early pregnancy. On the other hand, progesterone selectively inhibited hCG (alpha, beta) mRNAs expression and decreased hCG secretion in normal placental tissues, whereas choriocarcinoma did not respond to progesterone. This suggests that inhibitory regulation of hCG synthesis in choriocarcinoma is different from normal placenta. Characterization of choriocarcinoma hCG revealed that there are striking differences in carbohydrate structures between normal hCG and choriocarcinoma hCG. Sialic acid content in choriocarcinoma hCG was extremely lower compared to that in normal hCG. The biochemical detection of the alteration in hCG sugar chains is useful for early diagnosis of choriocarcinoma.

Increase in the expression of thyroid hormone receptors in porcine granulosa cells early in follicular maturation

Thyroid hormone has been demonstrated to synergize with FSH to exert stimulatory effects on the differentiation of porcine granulosa cells. In order to further characterize the nature of thyroid hormone action on granulosa cells, the presence of triiodothyronine (T3) receptors in the nuclei of porcine granulosa cells was examined, and qualitatively and quantitatively compared during follicular maturation. Then, comparative abilities of granulosa cells from varying follicle stages to respond to T3 were assessed in terms of FSH-induced LH/hCG receptor formation and progesterone secretion. Furthermore, the expression of erb-A was analyzed using Northern blot hybridization of porcine granulosa cell RNA with a v-erb-A probe. Binding experiments with [125I]T3 showed that granulosa cell nuclei obtained from small follicles had a greater ability to bind [125I]T3 compared to those from large follicles. Scatchard analysis revealed the presence of nuclear T3 receptors with a single class of binding sites. There was little difference in the affinity of the T3 receptors during follicular maturation. By contrast, the number of the T3 receptors was higher in small follicle granulosa cells compared to that in large follicle granulosa cells. Thus, the increased T3 binding to small follicle granulosa cells relative to large follicle granulosa cells appears to be attributable to the increased number of the nuclear T3 receptors rather than to a change in the affinity. The magnitude of the stimulatory effects of T3 on granulosa cell functions was maximal in small follicle granulosa cells, but negligible in large follicle granulosa cells.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of maternal thyroid hormones in maintaining early pregnancy in threatened abortion

To evaluate a possible role of thyroid hormones in maintaining early pregnancy, serum levels of thyroid hormones, TSH and thyroxine-binding globulin (TBG) in 32 patients with a clinical diagnosis of threatened abortion were compared between two groups of patients with favorable and unfavorable pregnancy outcome. Serum levels of T4, T3, free T4 and free T3 levels determined at the onset of clinical signs of threatened abortion were found to be significantly lower in patients (N = 11) who subsequently aborted compared to patients (N = 21) who did not. Serum TSH levels did not differ between the two groups. Serum TBG levels in the patients who subsequently aborted were lower compared to patients with favorable pregnancy outcome. Furthermore, serum levels of T4 and T3 at the onset of threatened abortion in patients who subsequently did not abort were significantly higher compared to levels before pregnancy, whereas little increase in serum T4 and T3 levels relative to the pregnant levels was observed at the onset of clinical signs in the patients who subsequently aborted. These data imply a possible role of thyroid hormones in maintaining early pregnancy, and suggest that maternal serum level of thyroid hormone may be one of the endocrine factors responsible for the outcome of threatened abortion.

A novel change in cytologic localization of human chorionic gonadotropin and human placental lactogen in first-trimester placenta in the course of gestation

Cytologic localization of human chorionic gonadotropin and human placental lactogen in developing human early placenta was analyzed by avidin-biotin immunoperoxidase techniques with an affinity-purified polyclonal antibody to beta-human chorionic gonadotropin carboxyl terminal peptide and a polyclonal antibody to human placental lactogen. In 4- to 5-week placentas human chorionic gonadotropin and human placental lactogen were found to be primarily localized to cytotrophoblasts, whereas in 6- to 12-week placentas these substances were exclusively localized to syncytiotrophoblast. We previously reported that a similar change in cytologic localization of epidermal growth factor and its receptor from cytotrophoblasts to syncytiotrophoblast in first-trimester placenta appeared between 5 and 6 weeks of gestation. Because epidermal growth factor was demonstrated to stimulate human chorionic gonadotropin and human placental lactogen production by early placental tissues, their simultaneous expression, as well as epidermal growth factor and its receptor in the cytotrophoblast of 4- to 5-week placenta and in the syncytiotrophoblast of 6- to 12-week placenta, implies that human chorionic gonadotropin and human placental lactogen production by first-trimester placenta may be regulated in an autocrine manner, wherein epidermal growth factor may serve as the signal. These findings suggest that in very early placenta, before 6 weeks of gestation, no sequential expression of human chorionic gonadotropin and human placental lactogen closely linked to syncytia formation may exist and that both can be expressed in the cytotrophoblast or undifferentiated stem cell of villous trophoblast in very early placenta.

[The role of signal transduction systems in the regulation of production and secretion of TA-4 by cultured cervical epidermoid carcinoma cells (CaSki)]

The CaSki cell line derived from an epidermoid carcinoma of the uterine cervix produces and releases a tumor associated-antigen, TA-4. The authors have already reported that EGF stimulated the production and secretion of TA-4 by the CaSki cells. EGF receptor is known to be one of the proteins phosphorylated by C-kinase. In order to elucidate a possible role of signal transduction systems (cAMP-A-kinase, diacyglycerol-C-kinase and Ca(2+)-calmodulin) in the regulation of TA-4 production and secretion by human cervical epidermoid carcinoma cells, the effects of cholera toxin (CT), an activator of adenylate cyclase, phorbol 12-myristate 13-acetate (PMA), a protein kinase C activator, and Ca2+ ionophore A23187, an activator of Ca2+ modulation on TA-4 production and secretion by CaSki cells were evaluated. TA-4 in the cultured cells and media were measured with a SCC RIA-Kit. The addition of PMA or Ca2+ ionophore to the medium caused increases in the cellular levels of TA-4 and TA-4 levels in the medium in a dose-dependent manner shortly after the addition. Combined treatment with PMA and Ca2+ ionophore did not cause additive increases in TA-4 levels in the cells and medium compared to the treatment with PMA alone or Ca2+ ionophore alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical demonstration of elevated expression of epidermal growth factor receptor in the neoplastic changes of cervical squamous epithelium

To evaluate epidermal growth factor (EGF) receptor expression in the neoplastic process of squamous cell epithelium of the uterine cervix, normal, premalignant, and malignant cervical tissues were examined for the presence of EGF receptor by the avidin-biotin immunoperoxidase techniques with a monoclonal antibody to EGF receptor. Although normal cervical epithelium did not show appreciable staining for EGF receptor, predominant staining for the receptor was observed in most dysplastic epithelia and carcinomas in situ. In invasive squamous carcinoma, there was a great difference in the immunohistochemically detected levels of EGF receptor among the histologic cell types. Large cell nonkeratinizing carcinoma and its keratinizing counterpart contained high levels of EGF receptor; small cell nonkeratinizing carcinoma lacked immunostainable EGF receptor. These results suggest that the elevated expression of EGF receptor may be involved in the initial stage of tumorigenesis of cervical squamous epithelium and that EGF receptor expression may be related to the differentiation or dedifferentiation of cervical squamous carcinoma cells.

A role for thyroid hormone in the induction of ovulation and corpus luteum function

We have previously demonstrated that thyroid hormone synergizes with follicle-stimulating hormone (FSH) to exert stimulatory effects on granulosa cell differentiation and function, suggesting that it plays a physiological role in amplifying FSH-mediated differentiation of granulosa cells. The adequate differentiation of these cells, followed by normal follicle development, is indispensable for ovulation and subsequent corpus luteum formation. Thus, in the present studies, the clinical implications of thyroid hormone in the induction of ovulation and corpus luteum function were investigated. Serum levels of total 3,5,3'-triiodothyronine (T3) and total thyroxine (T4) as well as free T3 and T4 were significantly lower in patients with weight loss amenorrhea compared to normal cycling women. Although no ovulation was induced by clomiphene therapy when the serum T3 levels were less than 80 ng/dl, the rate of ovulation induced by clomiphene increased in parallel with the augmentation of serum T3 levels. This suggests that an adequate circulating level of thyroid hormone is one of the factors responsible for successful induction of ovulation by clomiphene citrate. Furthermore, the short luteal phase and insufficient progesterone secretion observed in patients with subclinical hypothyroxinemia were not improved by clomiphene therapy alone, but were improved markedly by combined treatment with thyroid hormone replacement and clomiphene citrate. These data imply that concomitant clomiphene treatment with thyroid hormone replacement therapy is of a great value not only for ovulation induction, but also for the treatment of luteal-phase defect in patients with subclinical hypothyroxinemia.

[Effects of epidermal growth factor on the proliferation and differentiation of procine granulosa cells cultured in vitro]

Various growth factors are likely to be involved in the proliferation and differentiation of granulosa cells. Our previous studies revealed that insulin, insulin-like growth factor (IGF-I) and thyroid hormone each act as a biological amplifier of the action of FSH in the ovary. This study was undertaken to elucidate a possible direct effect of epidermal growth factor (EGF) on granulosa cell functions using the procine model. Porcine granulosa cells obtained from small, medium and large follicle, were cultured in the presence or absence of FSH and IGF-I, with or without EGF. EGF stimulated the proliferation of granulosa cells from small follicles, but did not affect the proliferation of granulosa cells from large follicles. In culture of granulosa cells obtained from large follicles. EGF inhibited the secretion of estradiol, and increased the secretion of progesterone by cultured cells. Scatchard analysis of 125I-EGF binding revealed that there is a single type of EGF receptor (EGF-R) in granulosa cells and that the number of EGF-R increases as the follicle matures. In Sephadex G-75 column chromatography of the medium following 5-day culture of porcine granulosa cells, an elution peak of immunoreactive EGF was found in the fraction similar to the elution of 125I-hEGF. These results suggested that EGF is produced by granulosa cells which contain abundant EGF-R. Thus, EGF is likely to act in an autocrine manner to stimulate the proliferation of less mature granulosa cells and to increase progesterone production by mature granulosa cells in association with an inhibitory action on estradiol production. These dual actions of EGF on granulosa cell function are of great interest.

[Modification of endocrine function of trophoblasts by thyroid hormone]

Direct effects of L-triiodothyronine(T3) on placental endocrine function were investigated in vitro with an organ culture system for human placental tissues. Explants of trophoblastic tissues obtained from early and term placentas were cultured with or without graded doses of T3 in a serum-free condition. The addition of an optimal concentration of T3(10(-3) M T3) stimulated daily secretion of progesterone and estradiol from cultured early placental tissues by acting at the level of 3 beta-hydroxysteroid dehydrogenase and aromatase enzyme activity, together with the enhancement of hCG(alpha, beta) and hPL secretion. The addition of higher or lower concentrations of T3 gave attenuated effects and the addition of an excessive concentration of T3(10(-3) M T3) resulted in remarkable inhibition of progesterone and estradiol secretion by cultured early placental tissues. These results suggest that the optimal concentration of thyroid hormone acts as a biological amplifier of endocrine function of cultured trophoblasts obtained from early placentas. Unlike the early placental tissues, cultured term placental tissues did not respond to the addition of graded doses of T3 with increased endocrine function. Thus, the frequent occurrence of spontaneous abortion in early pregnancy during the state of hypothyroidism or hyperthyroidism may represent a direct consequence of inadequate thyroid hormone availability at the level of the trophoblast, followed by diminished endocrine function of early placental trophoblasts.

Cytologic localization of epidermal growth factor and its receptor in developing human placenta varies over the course of pregnancy

Cytologic localization of epidermal growth factor and its receptor in developing human placenta was analyzed by avidin-biotin immunoperoxidase techniques with a polyclonal antibody to epidermal growth factor and a monoclonal antibody to its receptor. In 4- to 5-week placenta, epidermal growth factor and its receptor were found to be almost exclusively localized to cytotrophoblasts, whereas in 6- to 12-week placentas they were predominantly localized to syncytiotrophoblasts. These findings suggest that both are initially expressed in cytotrophoblasts in very early placenta before 6 weeks' gestation and thereafter expressed in syncytiotrophoblasts in 6- to 12-week placentas. Their simultaneous expression in the cytotrophoblast of 4- to 5-week placentas and in the syncytiotrophoblast of 6- to 12-week placentas implies that epidermal growth factor may act in an autocrine manner in first-trimester placentas. By contrast, in second- and third-trimester placentas, epidermal growth factor was mainly localized to cytotrophoblasts, whereas its receptor was predominantly localized to syncytiotrophoblasts. These findings imply that epidermal growth factor may act in a paracrine fashion in second- and third-trimester placentas. The dynamic change in cytologic localization of epidermal growth factor and epidermal growth factor receptor in developing human placentas may reflect the change in a possible role of epidermal growth factor in the course of fetoplacental development.

Thyroid hormone as a biological amplifier of differentiated trophoblast function in early pregnancy

Direct effects of T3 or T4 on the trophoblast function were investigated in vitro using an organ culture system of human placental tissues. Explants of trophoblastic tissues obtained from normal early and term placentas were cultured with or without graded doses of T3 or T4 for 5 days in a serum-free condition. Addition of T3 (10(-8) mol/l) resulted in the maximum increase in daily secretion of progesterone, estradiol-17 beta as well as hCG alpha, hCG beta, hCG and hPL by cultured early placental tissues. Increases in progesterone and estradiol-17 beta secretion caused by the addition of T3 were further augmented in response to concomitant addition of pregnenolone and testosterone, respectively, suggesting that T3 (10(-8) mol/l) enhances 3 beta-hydroxysteroid dehydrogenase and aromatase activity in the placenta. These stimulatory effects of T3 (10(-8) mol/l) on the trophoblast endocrine function were also found with the use of T4 (10(-7) mol/l). Addition of higher or lower concentrations of T3 or T4 gave attenuated effects. These results suggest that the optimal concentration of thyroid hormone is needed for it to exert its maximally stimulatory action on trophoblast endocrine function. Unlike early placental tissues, cultured term placental tissues did not respond to the addition of T3 or T4 with increased endocrine activity. Thus, the frequent occurrence of spontaneous abortion in early pregnancy during the state of hypothyroidism or hyperthyroidism may represent a direct consequence of inadequate thyroid hormone availability at the level of placental trophoblasts, followed by diminished expression of trophoblast endocrine function.

[The role of signal transduction systems in the regulation of the production and secretion of hCG (alpha, beta) by cultured human choriocarcinoma cells (BeWo)]

The BeWo cell line, derived from choriocarcinoma, produces and releases human chorionic gonadotropin (hCG) and its alpha- and beta-subunits. The authors have already reported that cAMP and EGF stimulated the production and secretion of hCG and its subunits by cultured BeWo cells. Therefore, in order to elucidate the role of signal transduction systems (cAMP-A-kinase system, DG-C-kinase system and Ca(2+)-calmodulin system) in the regulation of hCG (alpha, beta) synthesis by human choriocarcinoma cells, effects of cholera toxin (CT), an activator of adenylate cyclase, phorbol 12-myristate 13-acetate (PMA), a protein kinase C activator, and Ca2+ ionophore A23187, an activator of Ca2+ modulation on hCG (alpha, beta) production and secretion by BeWo cells cultured in a serum-free condition were evaluated. Immunoreactive hCG alpha, hCG beta and hCG in the media and cultured cells were measured by each homologous RIA for hCG alpha, hCG beta and hCG, respectively. Addition of CT at a concentration of 100 ng/ml into the medium caused extreme increases in the cellular levels of hCG alpha, hCG beta and hCG together with remarkable increases in hCG alpha, hCG beta and hCG levels in the medium. This stimulatory effect of CT was first observed on the increase of hCG alpha levels in cultured BeWo cells and medium at 3h, then observed on the increase of hCG beta levels at 6h and was last detectable on the increase of hCG levels in the cultured cells and medium at 12h. Addition of PMA at a concentration of 100 ng/ml into the medium caused an increase in the cellular and medium levels of hCG alpha, hCG beta and hCG shortly (3h) after the exposure to PMA. Addition of A23187 at a concentration of 100 ng/ml into the medium caused a slight increase in hCG alpha levels in the medium at 6h without accompanying the increase in those cellular levels. When added together, PMA potentiated the stimulatory effect of CT on hCG alpha, hCG beta and hCG levels in the cultured BeWo cells and medium, while PMA did not potentiate the effect of A23187 in this experimental condition. These findings suggest that cAMP-A-kinase system plays a major role in the signal transduction of hCG (alpha, beta) synthesis and secretion by BeWo choriocarcinoma cells, and that DG-C-kinase system interacts synergistically with cAMP-A-kinase system in the regulation of hCG (alpha, beta) synthesis and secretion by BeWo cells. Ca(2+)-calmodulin system appears to participate in the regulation of hCG alpha secretion without affecting the synthesis of hCG (alpha, beta) in BeWo cells.

Vascular reactivity in normal and abnormal gestation

Preeclampsia is characterized by enhanced pressor responsiveness to angiotensin II. This report summarizes studies by our laboratory to investigate possible roles for calcium, sodium, membrane pumps, and the vasoactive hormones, atrial natriuretic peptide (hANP) and endothelin, in modulating the change in vascular reactivity characteristic of preeclampsia. Urinary calcium excretion, 1 alpha-25(OH)2D3 levels, and serum free calcium levels were all decreased, whereas parathyroid hormone levels and intraplatelet calcium concentrations were increased in women with preeclampsia. Erythrocyte sodium content was elevated, while red blood cell membrane Na-K-ATPase activity was decreased in patients with severe disease. Preeclamptics also had elevated levels of hANP, which failed to increase further when saline was infused or when blood pressure was increased transiently with angiotensin II administration. Finally, endothelin levels that are reduced in normal gestation, were increased in preeclampsia. While the cause of increased vascular reactivity is still unclear, there appear to be changes in the intracellular cation environment, combined with loss of compensating mechanisms, both at the membrane and humoral level, as well as enhanced concentrations of a potent vasoconstrictor in blood; all which lead to increases in vasoreactivity and blood pressure in preeclampsia.

Penetration of fleroxacin into maxillary sinus mucosa and palatine tonsil

Ten patients undergoing tonsillectomy or operation on the maxillary-antrum were given 200 mg fleroxacin orally 1-2 h before surgery. The concentration of fleroxacin in maxillary sinus mucosa (mean 2.61 mg/kg) was similar to that in serum samples collected simultaneously (mean 2.46 mg/l); and similar results were obtained with tonsillar tissue (mean 3.27 mg/kg; simultaneous serum samples, mean 2.84 mg/l).

Long-term results after strabismus surgery

The results of surgery after 4 years' or more postoperative follow-up have been evaluated in a total of 1031 cases (575 esotropia, 456 exotropia). There is a difference in the angle of strabismus 1 month after surgery and 4 years after surgery. Based on these findings, the results of strabismus surgery must be evaluated after a sufficient amount of time has passed. The angle of strabismus to be aimed at, to provide best binocular vision and patient satisfaction, should be in the range of -2 +7 degree for esotropia and +2 -10 degree for exotropia, regardless of the patient's age at surgery.

Comparison of the facilitative roles of insulin and insulin-like growth factor I in the functional differentiation of granulosa cells: in vitro studies with the porcine model

The facilitative effects of insulin and IGF-I were compared in vitro with regard to induction of differentiated functions of porcine granulosa cells. The monolayers were maintained under serum-free conditions in the absence or presence of porcine FSH (20 micrograms/l), with or without graded doses of insulin or IGF-I. Concurrent treatment with IGF-I and FSH produced morphological differentiation and augmented LH/hCG receptor binding together with an enhancement in progesterone and estradiol secretion relative to treatment with FSH alone. IGF-I alone was incapable of exhibiting these effects. Insulin synergized with FSH to facilitate the granulosa cell functions except estradiol secretion. Maximal effective dose of IGF-I was 100 micrograms/l which is within the physiological concentration in vivo, whereas that of insulin was 1.0 mg/l, which is 1000-fold higher than the physiological level. Although the maximal effective doses of IGF-I and insulin produced a comparable increment in progesterone secretion and LH/hCG receptor induction, combined treatment with IGF-I and insulin did not prove additive. [125I]IGF-I binding revealed that specific IGF-I receptors with two classes of binding sites are present on porcine granulosa cells. No distinct differences were detected between IGF-I receptors of granulosa cells from small, medium and large follicles. Insulin was approximately 100-fold less active than IGF-I in competing for [125I]IGF-I binding. These findings suggest that porcine granulosa cells possess specific IGF-I binding sites which may mediate the cytodifferentiative actions of insulin-like peptides. Since IGF-I is more potent than insulin in amplifying the actions of FSH and maximally exerts the cytodifferentiative effects at the physiological concentration, it is likely that IGF-I plays the more important role in granulosa cell differentiation in synergy with FSH.

[Immunohistochemical studies on epidermal growth factor receptor and the myc oncogene product in squamous cell carcinoma of the uterine cervix]

Recent studies have demonstrated that the amount of epidermal growth factor receptor (EGF-R) is increased in squamous cell carcinoma cells and that the amino acid sequence of EGF-R shows great homology with the v-erb B transforming protein. In this study, we examined the tissue localization of EGF-R and myc oncogene product in normal squamous epithelium, dysplasia, carcinoma in situ, invasive squamous cell carcinoma of the uterine cervix and in metastatic lymph nodes by means of the avidin/biotin immunoperoxidase technique. Normal squamous epithelium was negative for EGF-R and myc product. The lesions of dysplasia and carcinoma in situ had a positive staining for EGF-R, but were still negative for myc product. There were differences in the staining intensity of EGF-R and myc product among the types of invasive carcinoma. Staining for EGF-R and myc product was negative in small cell non-keratinizing carcinoma, whereas strong staining for both EGF-R and myc product was observed in large cell non-keratinizing and keratinizing carcinoma. The intensity of positive staining for EGF-R and myc product declined in the lesions of cancer pearl. Metastatic lymph nodes were remarkably stained for EGF-R and myc product, while non-metastatic lymph nodes were negative for EGF-R and myc product. Our observations suggest that the amplified expression of EGF-R and myc product may accompany the malignant transformation of squamous epithelium of the uterine cervix, together with the metastasis.

[Effect of thyroid hormone on steroidogenic enzyme induction in porcine granulosa cells cultured in vitro]

In order to elucidate the mechanism of thyroid hormone action on the ovary, direct effects of L-thyroxine (T4) or L-triiodothyronine (T3) on steroidogenic enzyme induction were investigated in vitro using a monolayer culture system of porcine granulosa cells obtained from small follicles. The cells were cultured in the absence or presence of porcine FSH (20ng/ml) for 6 days, with or without T4 or T3, under sparsely (4%) serum supplemented condition. The mechanism of thyroid hormone action on the granulosa cells was studied by testing the capability of thyroid hormone to enhance the steroidogenesis in response to exogenously provided substrates. Concomitant treatment with FSH (20ng/ml) and T4 (10(-7) M) caused a further increased production of progesterone in response to the addition of pregnenolone compared to that in the absence of pregnenolone. The same treatment with FSH and T4 also caused a further increased production of estrone in response to the addition of androstenedione. Concomitant treatment with 10(-9) MT3 demonstrated similar stimulatory effects on the steroidogenesis in cultured granulosa cells. T4 or T3 alone without FSH was incapable of exhibiting these stimulatory effects. Furthermore, aromatase activity in cultured granulosa cells assessed by the release of tritiated water from [1 beta-3H, 4-14C] androstenedione was significantly higher in the cells treated concomitantly with FSH (20ng/ml) and T4 (10(-7) M) than that in the cells treated with FSH alone. These results suggest that thyroid hormone synergizes with FSH and increases FSH-mediated induction of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and aromatase activity in immature granulosa cells. Since the effective dose of T4 and T3 observed in our studies is in the physiological range of circulating total levels of T4 and T3, it can be concluded that the synergism between FSH and thyroid hormone is of physiological importance to the full expression of FSH actions in the functional differentiation of immature granulosa cells.

The role of thyroid hormone as a biological amplifier of the actions of follicle-stimulating hormone in the functional differentiation of cultured porcine granulosa cells

To characterize thyroid hormone action on the ovary, the direct effects of T4 or T3 were investigated in vitro using a monolayer culture system of porcine granulosa cells. Monolayer cultures were maintained for 6 days in 4% serum-supplemented medium in the absence or presence of porcine FSH (20 ng/ml), with or without graded doses of T4 or T3. Combined treatment with FSH and T4 (10(-7) M) induced morphological alternation resembling epithelioid cells, while FSH alone or T4 alone failed to bring about the epithelioid morphology. Concomitant treatment with FSH and T4 (10(-7) M) markedly increased FSH-stimulated induction of [125I]iodo-human CG binding to cultured granulosa cells obtained from small follicles. The combined treatment with FSH and T4 (10(-7) M) also resulted in a significant increase in progesterone and estrogen secretion by the cultured cells relative to treatment with FSH alone. Increases in progesterone, 17 beta-estradiol, and estrone secretion caused by the combined treatment with FSH and T4 (10(-7) M) were further augmented in response to the addition of exogenously provided substrate pregnenolone, testosterone, and androstenedione, respectively. Furthermore, aromatase activity assessed by the release of [3H]water from [1 beta-3H, 4-14C]androstenedione was significantly higher in cells treated concomitantly with FSH and T4 (10(-7) M) than that in cells treated with FSH alone. All the stimulatory effects of T4 (10(-7) M) on the morphological and functional differentiation of cultured granulosa cells were also found in combined treatment with FSH and T3 (10(-9) M). Either treatment with higher or lower concentrations of T4 or T3 gave attenuated effects, and T4 or T3 alone without FSH was incapable of exhibiting these stimulatory effects. These findings suggest that thyroid hormones synergize with FSH to exert direct stimulatory effects on granulosa cell functions, including morphological differentiation, LH/human CG receptor formation and steroidogenic enzyme (3 beta-hydroxysteroid dehydrogenase and aromatase) induction. Hence, decreases in ovarian functions during the states of hypo- or hyperthyroidism may account for diminished responsiveness of the granulosa cells to FSH.

Differential effects of dibutyryl cyclic AMP and epidermal growth factor on the synthesis and secretion of human chorionic gonadotropin and its subunits by trophoblastic and non-trophoblastic cells

The effects of dibutyryl cyclic adenosine 3',5'-monophosphate (cAMP) and epidermal growth factor (EGF) on the synthesis and secretion of human chorionic gonadotropin (hCG) and its subunits by normal and malignant trophoblasts as well as by non-trophoblastic cells were investigated in vitro. The explants of normal early placental tissues, choriocarcinoma cell line BeWo and non-trophoblastic tumor cell line CaSki from epidermoid carcinoma of the cervix, respectively, were cultured in the presence or absence of dibutyryl cAMP or EGF. The addition of either dibutyryl cAMP (1 mM) or EGF (100 ng/ml) caused significant increases in the synthesis and secretion of hCG and its subunits in cultures of normal and malignant trophoblasts, but had no stimulatory effect on hCG beta synthesis and secretion in culture of non-trophoblastic cell line CaSki that secretes predominantly hCG beta-like material. The magnitude of the stimulatory effects of dibutyryl cAMP and EGF on hCG (alpha,beta) synthesis and secretion by BeWo cells was much greater than that observed in normal trophoblasts. The time course of these stimulatory effects indicated that EGF-stimulated increase in hCG synthesis and secretion required a lag period longer than that for the dibutyryl cAMP-stimulated increase. These results suggest that there were no differences in normal and malignant trophoblasts in the mechanism for the stimulatory regulation of hCG (alpha, beta) synthesis and secretion, but immunoreactive hCG beta synthesis and secretion in non-trophoblastic tumor cells are regulated by a mechanism different from that in trophoblastic cells.

Induction of differentiated trophoblast function by epidermal growth factor: relation of immunohistochemically detected cellular epidermal growth factor receptor levels

The effects of epidermal growth factor (EGF) on the production and secretion of hCG and human placental lactogen (hPL) by cultured placental tissues were investigated in relation to immunohistochemical measurements of cellular EGF receptor levels in the placenta. Explants of trophoblastic tissues obtained from normal early and term placentas were cultured in the presence or absence of EGF (100 ng/mL) with or without processing inhibitors (bacitracin, 1 mg/mL; colchicine, 100 microM; chloroquine, 100 microM) for 5 days, with EGF present for the first 2 days. Addition of EGF to the medium increased the release of hCG, hCG alpha, and hPL by the cultured early placental tissues. This EGF-stimulated hCG, hCG alpha, and hPL release was markedly inhibited by concomitant treatment with processing inhibitors. The time course of EGF effects indicated that the EGF-stimulated increase in hCG alpha secretion required a lag period of approximately 1 day, whereas significant increases in hCG and hPL secretion became apparent only after 3 days of EGF treatment. By contrast, in term placental tissues EGF stimulated only hCG alpha and hPL release, with a lag period of approximately 3 days. A possible direct action of EGF on the cultured placental tissues was reinforced by the immunohistochemical demonstration of EGF receptors in the placenta. When determined using the avidin/biotin immunoperoxidase method with monoclonal antibody to the mouse EGF receptor, EGF receptors were found predominantly on the syncytiotrophoblasts. Immunohistochemical measurements of cellular EGF receptor levels in the syncytiotrophoblasts revealed remarkably higher levels in early placenta compared to those in midterm and term placentas. Since EGF is likely to interact with its receptor, the lesser biological effects of EGF in cultures of term placental tissues may be due to the lower cellular EGF receptor levels in term placenta. These results demonstrate that EGF, via its receptors on the syncytiotrophoblasts, stimulates the release of both hCG and hPL in normal early placenta. They also suggest that EGF may play a significant role in the induction and regulation of the differentiated function of trophoblasts.