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The pulmonary neuroendocrine cells (PNEC) are located in the epithelial lining of the airways and consist of solitary neuroendocrine cells (NEC) and NEC clusters, the neuroepithelial bodies (NEB). During fetal life, PNEC are the first to differentiate within the primitive airway epithelium, and bombesin expression favors branching of the respiratory tree. We investigated PNEC in Down syndrome (DS), where the lungs often show enlarged and reduced number of alveoli. Immunohistochemistry for bombesin and synaptophysin, PNEC markers, was evaluated in fetal lungs from 15 cases of DS and 11 age-matched controls from the 17th to 23rd week of gestation. Morphometric analysis assessed PNEC in the mucosal lining of each lung, expressed as number/mm. Nonparametric Mann-Whitney U test showed no statistical difference in frequency of PNEC in DS and controls. Our findings suggest that, at least in late second trimester, the distribution and frequency of PNEC in DS fetuses is not altered.

We previously obtained evidence for reduced cell proliferation in the dentate gyrus (DG) of fetuses with Down syndrome (DS), suggesting that the hippocampal hypoplasia seen in adulthood may be caused by defective early neuron production. The goal of this study was to establish whether DS fetuses (17-21 weeks of gestation) exhibit reduction in total cell number in the DG, hippocampus and parahippocampal gyrus (PHG). Volumes of the cellular layers and cell number were estimated with Cavalieri's principle and the optical fractionator method, respectively. We found that in DS fetuses all investigated structures had a reduced volume and cell number. Analysis of cell phenotype showed that DS fetuses had a higher percentage of cells with astrocytic phenotype but a smaller percentage of cells with neuronal phenotype. Immunohistochemistry for Ki-67, a marker of cycling cells, showed that DS fetuses had less proliferating cells in the germinal zones of the hippocampus and PHG. We additionally found that in the hippocampal region of DS fetuses there was a higher incidence of apoptotic cell death. Results show reduced neuron number in the DS hippocampal region and suggest that this defect is caused by disruption of neurogenesis and apoptosis, two fundamental processes underlying brain building.

Objective To identify criteria useful for differentiating closed from open spina bifida antenatally. Patients and methods A retrospective study of cases of spina bifida diagnosed in a referral center between 1997 and 2004. Results Of 66 cases of fetal spina bifida diagnosed at a median gestational age of 21 (range, 16-34) weeks, detailed follow-up was available for 57. Of these, open defects were found in 53 (93.0%) and closed defects in four (7.0%). Closed spina bifida was associated in two cases with a posterior cystic mass with thick walls and a complex appearance, while in two cases the spinal lesion could not be clearly differentiated from an open defect, particularly at mid-gestation. Open spina bifida was always associated with typical alterations of cranial anatomy, including the so-called `banana' and `lemon' signs, while in closed spina bifida the cranium was unremarkable. When the data were available, levels of amniotic fluid alpha-fetoprotein were always abnormally elevated with open spina bifida and within normal limits with closed forms. Conclusion In this study 7% of cases of spina bifida diagnosed in utero were closed. The differentiation between open and closed forms is best shown by the sonographic demonstration of abnormal or normal cranial anatomy. [ABSTRACT FROM AUTHOR]

Objective To investigate the effectiveness of a simplified approach to the evaluation of the midline structures of the fetal brain using three-dimensional (3D) ultrasound. Methods Sonographic examinations were performed in normal fetuses and in cases with anomalies involving the midline cerebral structures. Two-dimensional (2D) median planes were obtained by aligning the transducer with the anterior fontanelle and midline sutures by either transabdominal or transvaginal scans. Median planes were also reconstructed using 3D ultrasonography from volumes acquired from transabdominal axial planes of the fetal head (3D median planes), by either multiplanar analysis of static volumes or volume contrast imaging in the coronal plane (VCI-C). 2D and 3D median planes were compared qualitatively and quantitatively by measuring the corpus callosum and cerebellar vermis. Results 2D median planes could be visualized in 54/56 normal fetuses. 3D median planes were obtained in all, usually more easily and rapidly. There was a good correlation between 2D and 3D images. Measurements of the corpus callosum and cerebellar vermis were highly correlated, with mean variations of 6% and 14%, respectively. The abnormal group included 13 fetuses (five with partial or complete agenesis of the corpus callosum, six with posterior fossa malformations, two with a combination of these two anomalies). In all cases the diagnosis could be made by both 2D and 3D views and was always confirmed by postnatal investigation. Although 2D median views were of better quality, 3D images were always adequate for diagnosis, both in normal and abnormal fetuses. Conclusions 3D median planes are obtained more easily than 2D ones, and allow an accurate diagnosis of normal cerebral anatomy and anomalies. The 3D approach may be valuable particularly for rapid assessment of fetal cerebral anatomy in standard examinations. [ABSTRACT FROM AUTHOR]

The article discusses a study on the clinical implications of fetal bilateral cleft lip and palate (BCLP) with premaxillary protrusion and BCLP with a flattened profile. This study examined 14 fetuses with BCLP identified via ultrasound by the University of Bologna's Department of Obstetrics and Gynecology during a 14-year period, from 1991-2005. It concludes that BCLP without premaxillary protrusion poses risks of lethal aneuplodies and trisomy 18 as proved by one third of the results.