Despite having amenorrhea and markedly elevated serum gonadotropin levels, some women with karyotypically normal spontaneous premature ovarian failure, nevertheless, have ovarian follicles that function intermittently. Graafian follicles capable of responding to these high FSH levels are faced with high serum LH levels as well, which might induce inappropriate luteinization and prevent normal follicle function. We examined this possibility using weekly blood sampling and sonography in 65 patients. Nearly 50% of our patients demonstrated ovarian follicle function [serum estradiol, > 183 pmol/L (50 pg/mL)] during a median of 4 months of observation (range, 2-6 months). However, during this observation, only 16% achieved an ovulatory serum progesterone level [> 9.5 nmol/L (3.0 ng/mL)]. We imaged an antral follicle by sonography in over 40% of patients (27 of 65), and serum estradiol was significantly greater when an antral follicle was present. The follicles in these patients were not functioning normally, however. In contrast to normal women, patients with ovarian failure had poor correlation between follicle diameter and serum estradiol. We biopsied these antral follicles in 6 patients and found luteinized Graafian follicles in all cases. Therefore, luteinized Graafian follicles account for at least 60% of the antral structures imaged (95% confidence limit). Thus, inappropriate luteinization of Graafian follicles appears to be a major pathophysiological mechanism in patients with karyotypically normal spontaneous premature ovarian failure.
Conjugates of an uronic acid-containing capsular polysaccharide (CP), pneumococcous type 12F (Pn12F) bound to diphtheria toxoid (DT), were studied for safety and immunogenicity in adult volunteers. In mice, these conjugates, prepared with the same lot of DT and Pnl2F-40234-006, a homogenous CP of high molecular weight, or Pnl2-812408, a polydisperse CP with lower-molecular-weight material, were more immunogenic than the Pnl2F alone and had T-cell dependent properties (Infect. Immun. 56:2292Immun. 56: -2298Immun. 56: , 1988. Adult volunteers, randomized into three groups, were injected either with one of these two conjugates or with Pnu-Imune, the 23 valent pneumococcus vaccine containing 25 ,ug of Pn12F as one of its components.Volunteers were injected two times, 4 weeks apart, with the Pnl2F-DT conjugates and once with the Pnu-Imune. Side reactions following injection of the conjugates or Pnu-Imune were mild and short-lived. At 4 weeks and at 7 months after the first injection, higher levels of Pnl2F antibodies were found in the volunteers injected with the conjugates than in the Pnu-Imune group (P < 0.001). The conjugate prepared with the higher-molecular-weight Pnl2F elicited higher levels of antibodies than the conjugate prepared with a lower-molecular-weight Pn12F preparation (P = 0.05). Both conjugates elicited about a 13-fold rise in DT antibodies.
Vascular endothelial growth factor (VEGF) is a cytokine that induces angiogenesis. Angiogenesis is a prominent histologic component of the luteinization process. Luteinization is also characterized by granulosa cell progesterone secretion in response to the luteinizing hormone (LH) surge. Local VEGF production in human pre-ovulatory follicles, induced by LH, was postulated to be a luteinization mediator in women. To investigate this hypothesis, serum and fluid from the dominant follicle of 31 healthy regularly cycling multiparous women undergoing laparoscopic sterilization were obtained. VEGF was measured by enzyme-linked immunosorbent assay, and LH and progesterone were measured by radioimmunoassay. Follicle aspiration was performed at a median of 13 days from the last menstrual period (range 11-17 days). The median pre-ovulatory follicle diameter was 16 mm (range 11-23 mm). Follicle fluid VEGF concentrations (mean 6900 pg/ml, range 1200-17 100 pg/ml) were correlated positively with follicle fluid progesterone concentrations (mean 10 176 nmol/l, range 636-66780 nmol/l, r=0.62, P=0.002). This correlation was even tighter (r=0.87, P < 0.0001) when only samples from the 22 women in the earliest stages of follicle luteinization were considered. In these women serum LH concentrations were also correlated with follicle fluid VEGF concentrations (r=0.51, P=0.02). Our findings demonstrate the close dynamic relationship between VEGF production and early luteinization in human follicles during normal non-stimulated cycles.
Glycoprotein hormone-free alpha subunit is secreted by the pituitary throughout the menstrual cycle and by the placenta during pregnancy. We showed previously that free alpha subunit stimulated PRL secretion from term pregnancy decidual cells, suggesting a function for free alpha in pregnancy. However, no role has been ascribed to free alpha in the normal menstrual cycle. Using an in vitro model, we examined the role of alpha subunit in regulating human endometrial stromal cell differentiation (decidualization). PRL and insulin-like growth factor binding protein-1 (IGFBP-1), specific decidual secretory products, were used as markers of decidualization. We found that alpha subunit acted synergistically with progesterone (P) to induce more rapid decidualization with higher output (2- to 6-fold) of PRL and IGFBP-1, compared with P alone (P < 0.01). The effect of alpha was dose dependent, with stimulatory activity starting at 0.05 ng/ml and reaching maximal levels at 1-2 ng/ml. These levels correspond to serum concentrations of free alpha found during the luteal phase of the menstrual cycle when endometrial decidualization occurs in vivo. These findings demonstrate new biological activity for alpha subunit in the regulation of human endometrial decidualization and indicate that free alpha plays a role in human reproduction. Furthermore, demonstration of potential bioactivities of free alpha subunit has important implications for understanding normal endocrine function and various pathological conditions.
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