The formation of endothelial tight junctions (TJs) is crucial in blood-brain barrier (BBB) differentiation, and the expression and targeting of TJ-associated proteins mark the beginning of BBB functions. Using confocal microscopy, this study analyzed endothelial TJs in adult human cerebral cortex and the fetal telencephalon and leptomeninges in order to compare the localization of two TJ-associated transmembrane proteins, occludin and claudin-5. In the arterioles and microvessels of adult brain, occludin and claudin-5 form continuous bands of endothelial immunoreactivity. During fetal development, occludin and claudin-5 immunoreactivity is first detected as a diffuse labeling of endothelial cytoplasm. Later, at 14 weeks, the immunosignal for both proteins shifts from the cytoplasm to the interface of adjacent endothelial cells, forming a linear, widely discontinuous pattern of immunoreactivity that achieves an adult-like appearance within a few weeks. These results demonstrate that occludin and claudin-5 expression is an early event in human brain development, followed shortly by assembly of both proteins at the junctional areas. This incremental process suggests more rapid establishment of the human BBB, consistent with its specific function of creating a suitable environment for neuron differentiation and neurite outgrowth during neocortical histogenesis.
The diagnosis of CE is more frequent in women with endometriosis. Although no etiologic relationships between CE and endometriosis can be established, this study suggests that CE should be considered and if necessary ruled out in women with endometriosis, particularly if they have abnormal uterine bleeding. Identification and appropriate treatment of CE may avoid unnecessary surgery.
BackgroundNanotubular structures, denoted tunneling nanotubes (TNTs) have been described in recent times as involved in cell-to-cell communication between distant cells. Nevertheless, TNT-like, long filopodial processes had already been described in the last century as connecting facing, growing microvessels during the process of cerebral cortex vascularization and collateralization. Here we have investigated the possible presence and the cellular origin of TNTs during normal brain vascularization and also in highly vascularized brain tumors.MethodsWe searched for TNTs by high-resolution immunofluorescence confocal microscopy, applied to the analysis of 20-µm, thick sections from lightly fixed, unembedded samples of both developing cerebral cortex and human glioblastoma (GB), immunolabeled for endothelial, pericyte, and astrocyte markers, and vessel basal lamina molecules.ResultsThe results revealed the existence of pericyte-derived TNTs, labeled by proteoglycan NG2/CSPG4 and CD146. In agreement with the described heterogeneity of these nanostructures, ultra-long (> 300 µm) and very thin (< 0.8 µm) TNTs were observed to bridge the gap between the wall of distant vessels, or were detected as short (< 300 µm) bridging cables connecting a vessel sprout with its facing vessel or two apposed vessel sprouts. The pericyte origin of TNTs ex vivo in fetal cortex and GB was confirmed by in vitro analysis of brain pericytes, which were able to form and remained connected by typical TNT structures.ConclusionsNone of the multiple roles described for TNTs can be excluded from a possible involvement during the processes of both normal and pathological vessel growth. A possible function, suggested by the pioneering studies made during cerebral cortex vascularization, is in cell searching and cell-to-cell recognition during the processes of vessel collateralization and vascular network formation. According to our results, it is definitely the pericyte-derived TNTs that seem to actively explore the surrounding microenvironment, searching for (site-to-site recognition), and connecting with (pericyte-to-pericyte and/or pericyte-to-endothelial cell communication), the targeted vessels. This idea implies that TNTs may have a primary role in the very early phases of both physiological and tumor angiogenesis in the brain.Electronic supplementary materialThe online version of this article (10.1186/s12987-018-0114-5) contains supplementary material, which is available to authorized users.
Aim: The study aimed to describe prenatal diagnosis and the outcome of complete hydatidiform mole and coexistent normal fetus (CHMCF). Methods: This was a retrospective case series of 13 patients with CHMCF. Prenatal diagnosis, outcome and development of gestational trophoblastic neoplasia (GTN) were reviewed. Results: Ultrasound diagnosis was carried out in 12 of 13 cases at 17 ± 2.7 weeks of gestation (mean ± SD). Six patients showed abnormalities suggestive of subchorionic hematoma on first trimester ultrasonography (US). Prenatal invasive procedures were performed in 8 of 13 cases (62%). Two women decided to terminate their pregnancies. Four ended in late miscarriages (36%, 4 of 11) between 13 and 21 weeks, and early neonatal death occurred in 1 case (9%, 1 of 11); 5 women delivered a live baby with a mean gestational age of 31 weeks (range 26-37 weeks) with an overall neonatal survival of 45% (5 of 11). GTN occurred in 31% of cases (4 of 13). Conclusions: The first trimester US features of CHMCF are not well-documented. Our series showed that abnormalities of CHMCF could be misdiagnosed as subchorionic hematoma in the early first trimester. When CHMCF is confirmed by expert US, prenatal invasive procedures should be carefully evaluated depending on the associated US findings and exhaustive counseling should be performed.
Specialist scan findings CCAML diaphragmatic hernia bright area in fetal heart ?echogenic focus ?rhabdomyoma cystic lesion in brain ?agenesis corpus collosum ?small left side heart large single atrium and ?AVSD CPCs, VSD and DORV Fetal medicine unit findings small CAM diaphragmatic hernia large apical VSD, dilated LV, dysplastic mv, small lvot cystic structure in brain not destroying tissue unlikely to have significant cardiac defect large atrial communication, tricuspid regurgitation not scanned Amniocentesis N/A Attemptedsuboptimal access Yes-normal chromosomes Declined Yes-normal chromosomes Declined Yes-DiGeorge syndrome Outcome baby appeared normal
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