The Experts below are selected from a list of 45639 Experts worldwide ranked by ideXlab platform
K H Nicolaides - One of the best experts on this subject based on the ideXlab platform.
-
cerebral Ventricular System in fetuses with open spina bifida at 11 13 weeks gestation
Ultrasound in Obstetrics & Gynecology, 2012Co-Authors: T Loureiro, F Ushakov, Nuno Montenegro, Yuval Gielchinsky, K H NicolaidesAbstract:OBJECTIVE: To determine if in fetuses with open spina bifida at 11-13 weeks' gestation there are alterations in the cerebral Ventricular System. METHODS: In this study we selected 10 cases of open spina bifida and 410 normal singleton pregnancies which subsequently resulted in the delivery of phenotypically normal neonates. In all cases transvaginal sonography was carried out at 11-13 weeks' gestation and three-dimensional (3D) brain volumes were acquired. The fetal head was Systematically assessed in a series of transverse views and measurements were obtained of the area of the lateral ventricles, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle. The measurements obtained on the normal and affected fetuses were compared. RESULTS: In normal fetuses the area of the lateral ventricles and the diameter of the roof of the third ventricle increased, the diameter of the aqueduct of Sylvius decreased and the diameter of the fourth ventricle did not change significantly with biparietal diameter (BPD). In fetuses with open spina bifida, compared with normal fetuses, the measurements of the lateral ventricle area, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle were significantly decreased (P < 0.01). CONCLUSION: In fetuses with open spina bifida at 11-13 weeks' gestation the intracranial collection of cerebrospinal fluid is substantially reduced.
-
cerebral Ventricular System in fetuses with open spina bifida at 11 13 weeks gestation
Ultrasound in Obstetrics & Gynecology, 2012Co-Authors: T Loureiro, F Ushakov, Nuno Montenegro, Yuval Gielchinsky, K H NicolaidesAbstract:Objective To determine if in fetuses with open spina bifida at 11–13 weeks' gestation there are alterations in the cerebral Ventricular System. Methods In this study we selected 10 cases of open spina bifida and 410 normal singleton pregnancies which subsequently resulted in the delivery of phenotypically normal neonates. In all cases transvaginal sonography was carried out at 11–13 weeks' gestation and three-dimensional (3D) brain volumes were acquired. The fetal head was Systematically assessed in a series of transverse views and measurements were obtained of the area of the lateral ventricles, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle. The measurements obtained on the normal and affected fetuses were compared. Results In normal fetuses the area of the lateral ventricles and the diameter of the roof of the third ventricle increased, the diameter of the aqueduct of Sylvius decreased and the diameter of the fourth ventricle did not change significantly with biparietal diameter (BPD). In fetuses with open spina bifida, compared with normal fetuses, the measurements of the lateral ventricle area, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle were significantly decreased (P < 0.01). Conclusion In fetuses with open spina bifida at 11–13 weeks' gestation the intracranial collection of cerebrospinal fluid is substantially reduced. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
T Loureiro - One of the best experts on this subject based on the ideXlab platform.
-
cerebral Ventricular System in fetuses with open spina bifida at 11 13 weeks gestation
Ultrasound in Obstetrics & Gynecology, 2012Co-Authors: T Loureiro, F Ushakov, Nuno Montenegro, Yuval Gielchinsky, K H NicolaidesAbstract:OBJECTIVE: To determine if in fetuses with open spina bifida at 11-13 weeks' gestation there are alterations in the cerebral Ventricular System. METHODS: In this study we selected 10 cases of open spina bifida and 410 normal singleton pregnancies which subsequently resulted in the delivery of phenotypically normal neonates. In all cases transvaginal sonography was carried out at 11-13 weeks' gestation and three-dimensional (3D) brain volumes were acquired. The fetal head was Systematically assessed in a series of transverse views and measurements were obtained of the area of the lateral ventricles, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle. The measurements obtained on the normal and affected fetuses were compared. RESULTS: In normal fetuses the area of the lateral ventricles and the diameter of the roof of the third ventricle increased, the diameter of the aqueduct of Sylvius decreased and the diameter of the fourth ventricle did not change significantly with biparietal diameter (BPD). In fetuses with open spina bifida, compared with normal fetuses, the measurements of the lateral ventricle area, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle were significantly decreased (P < 0.01). CONCLUSION: In fetuses with open spina bifida at 11-13 weeks' gestation the intracranial collection of cerebrospinal fluid is substantially reduced.
-
cerebral Ventricular System in fetuses with open spina bifida at 11 13 weeks gestation
Ultrasound in Obstetrics & Gynecology, 2012Co-Authors: T Loureiro, F Ushakov, Nuno Montenegro, Yuval Gielchinsky, K H NicolaidesAbstract:Objective To determine if in fetuses with open spina bifida at 11–13 weeks' gestation there are alterations in the cerebral Ventricular System. Methods In this study we selected 10 cases of open spina bifida and 410 normal singleton pregnancies which subsequently resulted in the delivery of phenotypically normal neonates. In all cases transvaginal sonography was carried out at 11–13 weeks' gestation and three-dimensional (3D) brain volumes were acquired. The fetal head was Systematically assessed in a series of transverse views and measurements were obtained of the area of the lateral ventricles, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle. The measurements obtained on the normal and affected fetuses were compared. Results In normal fetuses the area of the lateral ventricles and the diameter of the roof of the third ventricle increased, the diameter of the aqueduct of Sylvius decreased and the diameter of the fourth ventricle did not change significantly with biparietal diameter (BPD). In fetuses with open spina bifida, compared with normal fetuses, the measurements of the lateral ventricle area, the diameter of the roof of the third ventricle, the diameter of the aqueduct of Sylvius and the diameter of the fourth ventricle were significantly decreased (P < 0.01). Conclusion In fetuses with open spina bifida at 11–13 weeks' gestation the intracranial collection of cerebrospinal fluid is substantially reduced. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Vladimir Korzh - One of the best experts on this subject based on the ideXlab platform.
-
Camel regulates development of the brain Ventricular System.
Cell and tissue research, 2020Co-Authors: Shulan Yang, Alexander Emelyanov, May-su You, Melvin Sin, Vladimir KorzhAbstract:Development of the brain Ventricular System of vertebrates and the molecular mechanisms involved are not fully understood. The developmental genes expressed in the elements of the brain Ventricular System such as the ependyma and circumVentricular organs act as molecular determinants of cell adhesion critical for the formation of brain Ventricular System. They control brain development and function, including the flow of cerebrospinal fluid. Here, we describe the novel distantly related member of the zebrafish L1-CAM family of genes—camel. Whereas its maternal transcripts distributed uniformly, the zygotic transcripts demonstrate clearly defined expression patterns, in particular in the axial structures: floor plate, hypochord, and roof plate. camel expresses in several other cell lineages with access to the brain Ventricular System, including the midbrain roof plate, subcommissural organ, organum vasculosum lamina terminalis, median eminence, paraVentricular organ, flexural organ, and inter-rhombomeric boundaries. This expression pattern suggests a role of Camel in neural development. Several isoforms of Camel generated by differential splicing of exons encoding the sixth fibronectin type III domain enhance cell adhesion differentially. The antisense oligomer morpholino-mediated loss-of-function of Camel affects cell adhesion and causes hydrocephalus and scoliosis manifested via the tail curled down phenotype. The subcommissural organ’s derivative—the Reissner fiber—participates in the flow of cerebrospinal fluid. The Reissner fiber fails to form upon morpholino-mediated Camel loss-of-function. The Camel mRNA–mediated gain-of-function causes the Reissner fiber misdirection. This study revealed a link between Chl1a/Camel and Reissner fiber formation, and this supports the idea that CHL1 is one of the scoliosis factors.
-
Development of brain Ventricular System
Cellular and Molecular Life Sciences, 2018Co-Authors: Vladimir KorzhAbstract:The brain Ventricular System (BVS) consists of brain ventricles and channels connecting ventricles filled with cerebrospinal fluid (CSF). The disturbance of CSF flow has been linked to neurodegenerative disease including hydrocephalus, which manifests itself as an abnormal expansion of BVS. This relatively common developmental disorder has been observed in human and domesticated animals and linked to functional deficiency of various cells lineages facing BVS, including the choroid plexus or ependymal cells that generate CSF or the ciliated cells that cilia beating generates CSF flow. To understand the underlying causes of hydrocephalus, several animal models were developed, including rodents (mice, rat, and hamster) and zebrafish. At another side of a spectrum of BVS anomalies there is the “slit-ventricle” syndrome, which develops due to insufficient inflation of BVS. Recent advances in functional genetics of zebrafish brought to light novel genetic elements involved in development of BVS and circulation of CSF. This review aims to reveal common elements of morphologically different BVS of zebrafish as a typical representative of teleosts and other vertebrates and illustrate useful features of the zebrafish model for studies of BVS. Along this line, recent analyses of the two novel zebrafish mutants affecting different subunits of the potassium voltage-gated channels allowed to emphasize an important functional convergence of the evolutionarily conserved elements of protein transport essential for BVS development, which were revealed by the zebrafish and mouse studies.
-
Functional antagonism of voltage-gated K+ channel α-subunits in the developing brain Ventricular System.
Development (Cambridge England), 2016Co-Authors: Hongyuan Shen, Elke Bocksteins, Igor Kondrychyn, Dirk J. Snyders, Vladimir KorzhAbstract:The brain Ventricular System is essential for neurogenesis and brain homeostasis. Its neuroepithelial lining effects these functions, but the underlying molecular pathways remain to be understood. We found that the potassium channels expressed in neuroepithelial cells determine the formation of the Ventricular System. The phenotype of a novel zebrafish mutant characterized by denudation of neuroepithelial lining of the Ventricular System and hydrocephalus is mechanistically linked to Kcng4b, a homologue of the ‘silent’ voltage-gated potassium channel α-subunit Kv6.4. We demonstrated that Kcng4b modulates proliferation of cells lining the Ventricular System and maintains their integrity. The gain of Kcng4b function reduces the size of brain ventricles. Electrophysiological studies suggest that Kcng4b mediates its effects via an antagonistic interaction with Kcnb1, the homologue of the electrically active delayed rectifier potassium channel subunit Kv2.1. Mutation of kcnb1 reduces the size of the Ventricular System and its gain of function causes hydrocephalus, which is opposite to the function of Kcng4b. This demonstrates the dynamic interplay between potassium channel subunits in the neuroepithelium as a novel and crucial regulator of Ventricular development in the vertebrate brain.
K Rascher - One of the best experts on this subject based on the ideXlab platform.
-
The Ventricular System of the pigeon brain: a scanning electron microscope study.
Journal of Anatomy, 1994Co-Authors: P Mestres, K RascherAbstract:The fine structural features and regional differences of the ependyma in adult pigeons have been investigated by scanning electron microscopy. Pigeons of either sex were fixed with buffered glutaraldehyde (3%) and formaldehyde (0.5%) by intravascular perfusion. The brain was dissected using section planes adequate to expose each part of the Ventricular System. The specimens were then dehydrated, critical point dried and sputtered with gold. Depending upon the distribution of cilia, microvilli and single cilia, different areas were recognised in the 4 ventricles. The topographic locations of these areas were determined using the atlas of Karten & Hodos (1967). The medial surfaces of the 1st and 2nd lateral ventricles are more densely ciliated than the lateral surfaces. In the floor of the 4th ventricle the medial part is less ciliated than the lateral parts. The circumVentricular organs (subseptal organ, organum vasculosum of the lamina terminalis, infundibulum, choroid plexus, subcommissural organ, area postrema) show very characteristic surfaces and are surrounded by a transitional zone with the nonspecialized ependyma. In contrast, in the paraVentricular organ the transition to the nonspecialized ependyma is rather abrupt. The ependyma covering the trochlear nucleus appears densely ciliated, differing from that of the classic circumVentricular organs. Finally, the existence of openings in the caudal medullary velum, which represent direct communications between the ventricles and the subarachnoid space, was demonstrated.
Tomás Hernández - One of the best experts on this subject based on the ideXlab platform.
-
Morphological and Volumetric Assessment of Cerebral Ventricular System with 3D Slicer Software
Journal of Medical Systems, 2016Co-Authors: Miguel Gonzalo Domínguez, Cristina Hernández, Pablo Ruisoto, Juan A. Juanes, Alberto Prats, Tomás HernándezAbstract:We present a technological process based on the 3D Slicer software for the three-dimensional study of the brain’s Ventricular System with teaching purposes. It values the morphology of this complex brain structure, as a whole and in any spatial position, being able to compare it with pathological studies, where its anatomy visibly changes. 3D Slicer was also used to obtain volumetric measurements in order to provide a more comprehensive and detail representation of the Ventricular System. We assess the potential this software has for processing high resolution images, taken from Magnetic Resonance and generate the three-dimensional reconstruction of Ventricular System.
