Kazuaki Katayama

Pathophysiology and postnatal outcome of fetal hydrocephalus

At the National Kagawa Childrens or Kobe University Hospital, 24 cases of fetal hydrocephalus were managed between 1982 and 1988. There were 8 simple, 11 dysgenetic, and 5 secondary cases of hydrocephalus, and the fetal age at diagnosis ranged between 24 and 40 weeks of gestation (average 33.4 weeks). All were diagnosed using ultrasonography, with either magnetic resonance imaging or whole-body computed tomography, additionally performed in 10 patients to determine their usefulness in evaluating the morphology. Four patients underwent transabdominal or transvaginal cephalocentesis in the prenatal period and intracranial pressure was measured during the drainage of cerebrospinal fluid in two of these. Postnatal outcome was analyzed for each type of hydrocephalus. The results suggested that in such cases the fetal brain is subjected to extremely high intracranial pressures resulting from a mixture of hydrocephalic pressure and intermittent uterine constriction. Immediately after birth, the biparietal diameter was found to be increased by an average of 7.7 mm and the hydrocephalic state was transformed into the neonatal type characterized by macrocephaly and a relatively low intracranial pressure. Overall mortality was 25% and 16 of the 24 infants underwent the postnatal shunt procedure, largely at the neonatal stage. The follow-up period varied from 4 months to 6 years (average, 25.8 months for nonfatal cases) and the mean intelligence or developmental quotient was 45.2. There were no significant differences in postnatal outcome between the three major types of fetal hydrocephalus. Findings revealed that the length of the gestation period after the diagnosis of hydrocephalus has a significant effect on outcome (P<0.01). Based on these results, it is suggested that fetal hydrocephalus may be extremely hypertensive and that impairment of neuronal functional development accompanying its prenatal progression can be irreversible.

“Triggering” of Ovulation after Infusion of Synthetic Luteinizing Hormone Releasing Factor (LRF)

Abstract. Synthetic luteinizing hormone releasing factor (LRF) was infused intravenously for 6 hours into two women who had donor insemination. Supplemental LRF was injected subcutaneously after a 6 hours continuous infusion. Ovulation was triggered by LRF infusion and two successful pregnancies were achieved. It is suggested that ovulation might be triggered by a continuous intravenous infusion of synthetic LRF, if follicular development of the ovary is sufficient. It is concluded that “triggering” of ovulation by a continuous infusion of LRF might be a convenient means for controlling the timing of ovulation in case of donor insemination.

Acrania: Report of the First Surviving Case

The first known surviving case of acrania is presented. The patient was the first child of a 29-year-old Japanese woman. Fetal ventriculomegaly was documented in the 35th gestational week. Prenatal sonography and magnetic resonance imaging suggested hydrocephalus with a wide encephalomeningocele. The baby was born at 38 weeks of gestational age by vaginal delivery. The patient had no calvarium, but did have a complete skull base with a partial defect in the occipital scalp and an underlying dural defect. Subsequently, the patient underwent repair of the scalp defect. At 3 months of age, after hydrocephalus developed, a subduro-peritoneal shunt was placed because of cosmetic and nursing problems. His developmental quotient was 10 at 3 years.

The Radio-Immunoassay of Follicle-Stimulating Hormone (FSH) During Human Pregnancy: Serum Concentration and Response to Luteinizing Hormone Releasing Factor (LRF)

Abstract. Concentrations of follicle‐stimulating hormone (FSH) detectable by radio‐immunoassay and the FSH response to synthetic luteinizing hormone releasing factor (LRF) were measured in the sera of fourteen women during the first, the second and the third trimesters of pregnancy. Serum FSH was detectable, but relatively low in all the fourteen subjects throughout pregnancy. Moreover, exogenously administered synthetic LRF failed to stimulate serum FSH secretion from the anterior pituitary and there was no rise in serum FSH in all the fourteen pregnant women. Thus, it might be concluded that follicle‐stimulating activity of the hypophyseal gland is suppressed throughout human pregnancy by an unknown mechanism.

Scanning electron microscopic studies on stigmas in rat ovaries.

Abstract. Ultrastructural observations on stigmas in rat ovarian follicles have been performed by scanning electron microscopy. Stigmas were classified into two types under a dissecting microscope; extensively bulging vesicles (bleb‐type stigmas) and small, flat avascular areas (flat‐type stigmas). The bleb‐type stigma had lost its surface epithelial cells extensively, and the flattened and densely arranged fibroblasts without fibrous structures were exposed. These fibroblasts had short, serrate, cytoplasmic projections where multivesicular structure‐like granules were seen. By contrast, on the flat‐type stigma a small region of exposed stroma was covered with fibrous structures. Removal of the fibrous structures by the HCl‐collagenase method revealed that the exposed stroma consisted of stellate fibroblasts surrounding a small opening through which a few granulosa cells were about to discharge. When the cumulus mass was protruding, it was surrounded by the fibrous structures. These findings indicate that both the stellate fibroblast formation and the presence of fibrous structures are needed for the release of ova through the stigma.

Effect of follicle-stimulating hormone (FSH) and estrogen on follicle growth in rats.

SummaryThe effect of follicle-stimulating hormone (FSH) and diethylstilbestrol (DES) on ovarian follicle growth was studied in hypophysectomized rats, using histologic, autoradiographic and histochemical techniques. The administration of FSH to immature hypophysectomized rats stimulated the follicle growth with thickening of the theca layer and repair of “deficiency cells”. Although DES given to hypophysectomized rats also stimulated the follicle growth, the theca layer was relatively thin compared with that in FSH-treated rats. In order to detect cell division in a growing follicle, the number of labelled granulosa cells with tritiated thymidine as a proportion of the granulosa cells in a growing follicle were counted and the labelling indices of the granulosa cells were calculated. The labelling indices increased by the administration of FSH (p<0.05) or DES (p<0.05). The uptake of tritiated thymidine and leucine by the theca cells was enhanced only by FSH and was not stimulated by DES. The administration of FSH resulted in an increase of the histochemically demonstrable enzyme activity such as Δ5-3β-hydroxysteroid dehydrogenase (3β-HSD) or alkaline phosphatase in the theca cells. In contrast, the administration of DES did not stimulate the enzyme activity of the theca cells. Furthermore, FSH stimulated a release of estradiol and estriol from the ovary of hypophysectomized rat, whereas DES did not.Although ovarian follicle growth was stimulated by both FSH and DES, the effect of the two hormones on the theca cells was quite different and the secretion of estrogen was stimulated by FSH. The results suggest that FSH induced follicle growth of the ovary might be mediated by estrogen produced by the theca cells.

Morphological Evaluation of Fetus CNS and Its Related Anomalies: The advantages and limitations of prenatal diagnosis by means of MRI·US·CT

The morphological evaluation of the fetus central nervous system by means of ultrasonography (US), magnetic resonance imaging (MRI) and CT scan and its prenatal diagnostic value for CNS anomalies were analyzed. All subjects, a total of 31 patients with 42 lesions, had been diagnosed during the preceding 7 years. The patients included 24 with hydrocephalus, three with anencephaly, three with myeloschisis, three with holoprosencephaly, three with an encephalocele, two with a Dandy-Walker cyst, one with hydroencephalodysplasia, one with an intracranial neoplasm, one with sacrococcygeal teratoma, and one with sacral agenesis.

Effect of pituitary gonadotrophins on tritiated thymidine uptake by rat ovary. An autoradiographic study

SummaryThe effect of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on the follicular growth in the ovary of the hypophysectomized rat was investigated using autoradiography. The numbers of DNA-synthesizing nuclei in the granulosa cell were measured by autoradiography after flashlabelling with tritiated (3H) thymidine. The frequency of3H-thymidine labelled nuclei in the granulosa cell enhanced in the presence of FSH. In contrast, LH had no significant effect on thymidine uptake. The result suggests that FSH stimulates follicle cell division, whereas LH does not.

Growth Factors in Placental Function

The trophoblast in early human placenta is composed of two distinct layers: an outer cell layer of multinuclear syncytiotrophoblast and inner cell layer of mononuclear cytotrophoblast. The cytotrophoblast displays highly proliferative and invasive properties very early in the first trimester. It is now evident that the syncytiotrophoblast is formed from the cytotrophoblast by a process of proliferation followed by cell fusion(1), and displays little potential for proliferation. However, regulatory factors involved in processes of proliferation and differentiation of the placental trophoblast still remain to be elucidated.