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Between 1932 and 1963 University of Pittsburgh anatomist Davenport Hooker, Ph.D., performed and filmed noninvasive studies of reflexive movement on more than 150 surgically aborted human fetuses. The resulting imagery and information would contribute substantially to new visual and biomedical conceptions of fetuses as baby-like, autonomous human entities that emerged in the 1960s and 1970s. Hooker's methods, though broadly conforming to contemporary research practices and views of fetuses, would not have been feasible later. But while Hooker and the 1930s medical and general public viewed live fetuses as acceptable materials for nontherapeutic research, they also shared a regard for fetuses as developing humans with some degree of social value. Hooker's research and the various reactions to his work demonstrate the varied and changing perspectives on fetuses and fetal experimentation, and the influence those views can have on biomedical research.

Context: The signals initiating growth of primordial follicles are unknown. Bone morphogenetic protein 15 (BMP15) and growth differentiating factor 9 (GDF9) are promising candidates., Objective: The objective of the study was to evaluate for the first time the effects of human recombinant BMP15 and human recombinant GDF9 on the in vitro development of human primordial follicles., Design and Setting: This was a controlled culture study performed in a major tertiary university-affiliated medical center., Materials: Materials included ovarian tissue from 17 girls/women and three aborted human fetuses., Intervention: There were no interventions., Main Outcome Measure: Histological and immunohistochemical (proliferating cell nuclear antigen, BMP15, and GDF9) studies and an endocrine assay of 17β-estradiol were conducted., Results: In the samples from girls/women, the number of developing follicles was greater with GDF9 or BMP15 alone than with no BMP15 or GDF9. Higher 17β-estradiol secretion was noted after treatment with GDF9 than with BMP15 or with GDF9+anti-GDF9. The number of atretic follicles was greater with BMP15 than with GDF9. Proliferating cell nuclear antigen expression was greater with the higher dose of both growth factors than the lower dose. Expression of BMP15 and GDF9 was identified in samples cultured without BMP15 or GDF9. Results for the fetal follicles yielded no distinguishable pattern., Conclusions: Although both BMP15 and GDF9 promoted activation of human primordial follicles from girls/women (but not human fetuses) in a dose-dependent manner, GDF9 seems more beneficial.

Vanishing fetal twins occurred in 9% (264 out of 2,829) intracytoplasmic sperm injection pregnancies and are associated with a lower fetal loss rate in the first trimester. The live birth rate was higher in pregnancies associated with vanishing fetuses., (Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare aneuploidy rates in first trimester pregnancy losses following IVF+/-ICSI., Methods: A retrospective cohort analysis of karyotypes of abortuses following conventional IVF (n=159) and ICSI (n=196)., Results: 50.1% of losses were found to be cytogenetically abnormal among all patients undergoing IVF+/-ICSI. A significant increase in fetal aneuploidy rate was noted with increasing maternal age (<30 years=26.1% vs. 31 to 34 years.=38.2% vs. 35 to 39 years.=51.3% vs. >39 years.=65.9%). Aneuploidy rates were similar in the ICSI vs. conventional IVF groups (52.6% vs. 47.2% [p 0.31, RR 1.11, 95% CI 0.90, 1.38]). More sex chromosome anomalies were noted in the ICSI group., Conclusions: The aneuploidy rate in first trimester abortuses significantly increases with increasing maternal age. ICSI was not shown to significantly increase the aneuploidy rate. However, more sex chromosome anomalies were found among pregnancies resulting from ICSI.

A conscience vote of individual parliamentarians in the Australian government last month regarding amendments to current legislation regulating human embryonic stem cell research yielded a surprising outcome. Despite opposition by the Australian Prime Minister, the Senate and House of Representatives voted to adopt the recommendations of the Lockhart Review and approve human somatic cell nuclear transfer, thus providing a consistent national policy for all researchers in Australia.

The ventriculus terminalis (VT) is a dilated cavity within the conus medullaris of the spinal cord. Although the VT was discovered in the mid-nineteenth century, little is known about its characteristics during development in human fetuses. Ependymal cells lining the cavities within the CNS retain high differentiation potential, and are believed to be responsible for the postnatal neurogenesis. To evaluate the differentiation capacity of the ependymal cells lining the VT during development, we examined glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) expression in the spinal cord of 18-24-week-old human fetuses. GFAP is a marker for the degree of ependymal cell differentiation in the human fetus, and PCNA is a well-known marker for cell division. Morphological characteristics of the VT were also examined. At the lower portion of the conus medullaris, the central canal abruptly expands dorsally to become the VT. Then the VT widens bilaterally while its anteroposterior diameter reduces gradually in a caudal direction. Finally, the VT becomes a narrow, transverse slit at the level of the lowermost conus medullaris. Compared with those lining the central canal, more numerous ependymal cells lining the VT showed more intensive GFAP and PCNA expression throughout all gestational ages examined. This suggests that, in the developing human spinal cord, ependymal cells lining the VT retain their differentiation potential, including a higher proliferative capacity, until a later stage of development than those lining the central canal.

Since the last decade the Yolk sac (YS) has been a topic of increasing interest due to the growing use of high-resolution sonography in early determination of pregnancy. Human YS shape and diameter are indicators of viability of pregnancy during the early embryonic period. Nevertheless, the major interest concerns the vital function it plays in early embryo growth and development. Two compartments are recognized in this organ: the yolk sac proper and the vitelline stalk. In this study we report the identification and partial characterization of a glomus-like body in the wall of the secondary YS in humans. A detailed structural description is also presented on the time course of formation of this new structure, at precisely sequential stages between 4-8 wk post-conception. The significance of this new compartment on the YS function is analyzed. Light and scanning electron microscopy were used to investigate the microstructure of the YS and the vitelline stalk during the first 8 wk of development. Ten YSs were collected from embryos (aged between 24-50 days) obtained from emergency salpingectomies due to tubal ectopic pregnancy. From 5 wk onward a new structure was observed in the YS located near the apex of the pear-shaped yolk vesicle and closed to the connecting stalk. We designate this differentiation as glomus-like body. This structure is 1-1.5 mm long and merged from a pocket-like structure of the extraembryonic splanchnic mesoderm of the YS wall. It likely represents an area of convergence of the vascular network of the YS wall. Our findings underline the remarkable complexity of the human secondary yolk sac during early development. The detailed description of the microanatomy of this vital organ is of theoretical and practical interest in order to unravel the mechanisms used by the yolk sac to transport nutrients to the embryo.

The development and differentiation of the coelomic epithelium lining the paramesonephric ducts in human fetus, that gives rise to the female genital organs, have been ultrastructurally examined. The epithelium appeared pseudostratified, consisting of basal, microvillous and ciliated cells. In younger fetuses (12th gestational week) ciliogenic elements could be detected mainly on the developing tubal fimbriae, but most of the cells showed microvilli and often single cilia. In the subsequent phases of development, morphodynamics of cell renewal were documented by aspects of apoptosis. Fully ciliated cells were numerous on the fimbriae and at the utero-tubal junction, but not in the uterus; however, these were less abundant than those showing microvillous. In older fetuses (31st gestational week) microapocrine secretion by microvillous cells, in the form of droplets contacting cilia, could be observed. In the same fetuses the ectocervix was covered by a mature squamous epithelium, made up of polygonal flat desquamating cells, showing labyrinthine surface microplicae. Our observations demonstrated that ciliation in the human female genital organs, like that of other systems, is neither simultaneous nor uniform, and ciliated cells are gathered preferentially in strategic sites, to mediate germ cell migration and blastocyst implantation in adult life. These ultrastructural data seem to indicate that the female genital tract epithelium, at least in its general features, is sketched since fetal life, and cell morphodynamics, including microvillous and ciliated cell differentiation, as well as the secretory activity, are the morphological expression of the complex molecular mechanisms, involved in developmental biology and reproductive physiology.

The expression of the apoptosis inducer Fas (CD95/APO-1) surface receptor by human foetal neurons was investigated in vitro and ex vivo. Immunofluorescence studies of brain and spinal cord cells in primary cultures and of cryosections obtained from 9- and 10-week-old human foetuses, respectively, showed that all Fas-expressing cells were motoneurons (5.3 and 4.2% of the neurons in brain or spinal cord cultures, respectively) on the basis of morphology, reactivity with the monoclonal antibody SMI-32, a mostly motoneuronal marker and acetylcholine esterase expression. Fas was undetectable on the other cell types in culture. The ability of Fas to induce apoptosis of cultured cells from both tissues was determined by using the terminal transferase (TdT)-mediated dUTP nick-end labelling (TUNEL) method combined with the same double-staining procedure. Under basal culture conditions, about 9% of cells, all glial fibrillary acidic protein-expressing astrocytes, were apoptotic. After a 48-h incubation with Fas ligand, mean 28.5% of brain motoneurons and 29.4% of spinal motoneurons underwent apoptosis, with an inhibition by Z-IETD-FMK, a caspase-8 inhibitor. Hence, Fas appears to be functional through a caspase-8-dependent pathway in a subpopulation of human foetal motoneurons.