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2.
Neuroradiol J ; 32(2): 92-97, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30604653

ABSTRACT

Intracranial dermoid and epidermoid cysts are usually considered to be two different entities in the radiological and surgical literature. Epidermoid cysts are classically off midline in location, isointense to cerebrospinal fluid on T1 and T2-weighted images and have restricted diffusion, whereas dermoid cysts are classically midline in location, have T1-hyperintense regions due to the presence of fat and show facilitated diffusion. We report a case of radiological epidermoid cyst in baseline imaging, which evolved into a radiological dermoid cyst over time, and explain this unique occurrence with a review of the embryology and histopathogenesis of these cysts.


Subject(s)
Brain Neoplasms/diagnostic imaging , Brain Neoplasms/embryology , Dermoid Cyst/diagnostic imaging , Dermoid Cyst/embryology , Epidermal Cyst/diagnostic imaging , Epidermal Cyst/embryology , Brain Neoplasms/pathology , Brain Neoplasms/surgery , Dermoid Cyst/pathology , Dermoid Cyst/surgery , Epidermal Cyst/pathology , Epidermal Cyst/surgery , Humans , Magnetic Resonance Imaging , Male , Rupture, Spontaneous , Tomography, X-Ray Computed , Young Adult
4.
Ultrasound Obstet Gynecol ; 51(2): 269-273, 2018 02.
Article in English | MEDLINE | ID: mdl-28067000

ABSTRACT

We report the first series of cases of pericallosal curvilinear lipoma (CL) diagnosed prenatally and highlight the limitations in identifying a specific prenatal imaging pattern using ultrasound and magnetic resonance imaging (MRI). In all five of our cases, on ultrasound, the main feature leading to referral was a short corpus callosum. This subtle callosal dysgenesis was associated with a band of hyperechogenicity surrounding the corpus callosum, mimicking the pericallosal sulcus, which increased in size during the third trimester in three of the four cases in which sonographic follow-up was performed. On T2-weighted MRI, this band showed typical hypointensity in all cases; in contrast, on T1-weighted imaging, in only one case was there hyperintensity, suggestive of fat, as seen typically in the postnatal period. For appropriate prenatal counseling regarding outcome, it is important to identify or rule out CL when mild corpus callosal dysgenesis is observed. One should be aware of subtle diagnostic findings, such as a thin band of echogenicity surrounding the corpus callosum that is seen as a band of hypointensity on T2-weighted fetal MRI, and which may increase in size during gestation. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Subject(s)
Agenesis of Corpus Callosum/diagnostic imaging , Brain Neoplasms/diagnostic imaging , Corpus Callosum/diagnostic imaging , Lipoma/diagnostic imaging , Magnetic Resonance Imaging , Ultrasonography, Prenatal , Adult , Agenesis of Corpus Callosum/embryology , Agenesis of Corpus Callosum/pathology , Brain Neoplasms/congenital , Brain Neoplasms/embryology , Corpus Callosum/embryology , Corpus Callosum/pathology , Female , Genetic Counseling , Humans , Infant, Newborn , Lipoma/congenital , Lipoma/embryology , Male , Pregnancy
5.
Pediatr Radiol ; 48(3): 383-391, 2018 03.
Article in English | MEDLINE | ID: mdl-29184973

ABSTRACT

BACKGROUND: Pericallosal lipomas are often associated with corpus callosum dysgenesis. The diagnosis of lipoma, suggested on ultrasonography, relies on the classic T1 hyperintensity on magnetic resonance imaging (MRI). However, this feature may be absent prenatally. OBJECTIVE: Our objective was to study the changes of T1 intensity in fetal lipomas with comparison to postnatal/postmortem data and to assess the factors influencing the signal variations of pericallosal lipomas on prenatal MRI. MATERIALS AND METHODS: Patients with callosum dysgenesis and interhemispheric hyperechogenicity suggestive of a pericallosal lipoma with available postnatal or postmortem data were included. Gestational age, lipoma size and pattern, corpus callosum size and changes in fetal fat T1 intensity were recorded. Comparison with postmortem neuropathology was available for one fetus. RESULTS: Eleven patients with callosum dysgenesis and pericallosal lipomas (seven curvilinear and four tubulonodular) were included. All MRI scans were performed in the third trimester. Curvilinear lipomas were thinner and six cases were associated with prenatal T1 iso-intensity. Typical T1 hyperintensity appeared on postnatal MRI only. All tubulonodular lipomas were much larger and showed prenatal T1 hyperintensity. In two patients, the lipoma increased in size on postnatal MRI. CONCLUSION: The type and size of a lipoma influence T1 prenatal intensity. Absence of T1 intensity was observed in curvilinear lipomas only. Curvilinear lipomas are much thinner. Changes in T1 intensity may also be related to fat maturation within the lipoma and, subsequently, to gestational age. In the case of callosum dysgenesis, absence of prenatal T1 pericallosal hyperintensity should not exclude the diagnosis of pericallosal lipoma.


Subject(s)
Agenesis of Corpus Callosum/diagnostic imaging , Brain Neoplasms/diagnostic imaging , Corpus Callosum/diagnostic imaging , Lipoma/diagnostic imaging , Magnetic Resonance Imaging/methods , Adult , Agenesis of Corpus Callosum/embryology , Agenesis of Corpus Callosum/pathology , Autopsy , Brain Neoplasms/embryology , Brain Neoplasms/pathology , Corpus Callosum/embryology , Corpus Callosum/pathology , Female , Humans , Lipoma/embryology , Lipoma/pathology , Pregnancy , Retrospective Studies , Ultrasonography, Prenatal
6.
Fetal Diagn Ther ; 42(1): 42-47, 2017.
Article in English | MEDLINE | ID: mdl-27710969

ABSTRACT

INTRODUCTION: We report the rare finding of recurrent periventricular pseudocysts (PVPC) in consecutive pregnancies in 4 families and their postnatal outcome. MATERIALS AND METHODS: We reviewed the databases of 3 large ultrasound units searching for the diagnosis of PVPC in 2 pregnancies of the same patient. RESULTS: The first case of recurrent PVPC was diagnosed in 2011 and since then 3 additional families were diagnosed (8 cases of PVPC all in all). All fetuses underwent fetal MRI that confirmed the presence of frontal or frontocaudal PVPC. Amniocentesis, when performed, demonstrated a normal karyotype. Termination of pregnancy was carried out in 2 pregnancies in 2 of 4 families. The remaining 6 pregnancies ended with a term delivery, and to date all babies are developing normally. CONCLUSION: The rare finding of recurrent brain PVPC in consecutive pregnancies raises the possibility of a hereditary etiology as opposed to a sporadic event. As in isolated PVPC, frontocaudal 'familial PVPC' appears to carry a favorable prognosis.


Subject(s)
Brain Neoplasms/diagnostic imaging , Cysts/diagnostic imaging , Family Health , Abortion, Induced , Adaptor Proteins, Signal Transducing/genetics , Brain Neoplasms/embryology , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cohort Studies , Cysts/embryology , Cysts/genetics , Cysts/pathology , Cytoskeletal Proteins , DNA Mutational Analysis , Electronic Health Records , Female , Follow-Up Studies , Frontal Lobe , Humans , Infant, Newborn , Israel , Magnetic Resonance Imaging , Membrane Proteins/genetics , Mutation , Pregnancy , Prognosis , Retrospective Studies , Term Birth , Tumor Burden , Ultrasonography, Prenatal
7.
J Neuroimmunol ; 277(1-2): 168-75, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25465288

ABSTRACT

Subependymomas are usually treated with surgical resection; however, no standard, defined alternative medical therapy is recommended for patients who are not surgical candidates, owing to a paucity of molecular, immunological, and genetic characterization. To address this, an ex vivo functional analysis of the immune microenvironment in subependymoma was conducted, a subependymoma cytokine/chemokine microarray was constructed for the evaluation of operational immune and molecular pathways, and a subependymoma cell line was derived and used to test a variety of cytotoxic agents that target operational pathways identified in subependymoma. We found that immune effectors are detectable within the microenvironment of subependymoma; however, marked immune suppression is not observed. The subependymoma tissue microarrays demonstrated tumor expression of p53, MDM2, HIF-1α, topoisomerase II-ß, p-STAT3, and nucleolin, but not EGFRvIII, EphA2, IL-13RA2, CMV, CTLA-4, FoxP3, PD-1, PD-L1, EGFR, PDGF-α, PDGF-ß, PDGFR-α, PDGFR-ß, PTEN, IGFBP2, PI3K, MDM4, IDH1, mTOR, or Jak2. A topoisomerase inhibitor (WP744, IC50=0.83 µM) and a p-STAT3/HIF-1α inhibitor (WP1066, IC50=3.15 µM) demonstrated a growth inhibition of the subependymoma cell proliferation. Cumulatively, these data suggest that those agents that interfere with oncogenes operational in subependymoma may have clinical impact.


Subject(s)
Brain Neoplasms/pathology , Drug Screening Assays, Antitumor , Glioma, Subependymal/pathology , Neoplasm Proteins/metabolism , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Brain Neoplasms/embryology , Brain Neoplasms/metabolism , Cell Line, Tumor/drug effects , Cell Proliferation/drug effects , Colony-Forming Units Assay , Cytokines/genetics , Cytokines/metabolism , Cytotoxicity Tests, Immunologic , Dose-Response Relationship, Drug , Flow Cytometry , Gene Expression Regulation, Neoplastic/drug effects , Glioma, Subependymal/immunology , Glioma, Subependymal/metabolism , Humans , Neoplasm Proteins/genetics , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/immunology , Neoplastic Stem Cells/metabolism , Pyridines/chemistry , Pyridines/pharmacology , Signal Transduction/drug effects , Signal Transduction/physiology , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Tissue Array Analysis , Tyrphostins/chemistry , Tyrphostins/pharmacology
8.
J Biosci ; 39(4): 595-603, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25116614

ABSTRACT

Groundbreaking work by Obaid Siddiqi has contributed to the powerful genetic toolkit that is now available for studying the nervous system of Drosophila. Studies carried out in this powerful neurogenetic model system during the last decade now provide insight into the molecular mechanisms that operate in neural stem cells during normal brain development and during abnormal brain tumorigenesis. These studies also provide strong support for the notion that conserved molecular genetic programs act in brain development and disease in insects and mammals including humans.


Subject(s)
Brain Neoplasms/physiopathology , Brain/embryology , Drosophila melanogaster/embryology , Drosophila melanogaster/genetics , Neural Plate/embryology , Neural Stem Cells/physiology , Animals , Brain Neoplasms/embryology , Cell Differentiation/physiology , Cell Proliferation/physiology
9.
Curr Probl Diagn Radiol ; 41(6): 210-9, 2012.
Article in English | MEDLINE | ID: mdl-23009771

ABSTRACT

Germ cell tumors (GCTs) may occur in both children and adults and include a broad array of histologic subtypes, such as teratoma, seminoma (known as dysgerminoma in the ovary and germinoma in the pineal gland), choriocarcinoma, yolk sac tumor, embryonal cell carcinoma, and mixed GCT. In adults, GCTs occur most commonly in the gonads. In children, sacrococcygeal tumors predominate. Teratomas are a common form of GCT. They are defined histologically as containing tissues derived from all 3 germ cell layers: ectoderm, mesoderm (most teratomas contain fat, an imaging hallmark, which is a mesodermal derivative), and endoderm. Teratomas are also classified as mature or immature, depending on the degree of differentiation of its components, and in adults, immature tumors are more likely to exhibit malignant behavior.


Subject(s)
Brain Neoplasms/pathology , Endocrine Gland Neoplasms/pathology , Head and Neck Neoplasms/pathology , Mediastinal Neoplasms/pathology , Retroperitoneal Neoplasms/pathology , Teratoma/pathology , Adolescent , Adult , Age Distribution , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/embryology , Calcinosis/pathology , Child , Child, Preschool , Endocrine Gland Neoplasms/diagnostic imaging , Endocrine Gland Neoplasms/embryology , Female , Head and Neck Neoplasms/diagnostic imaging , Head and Neck Neoplasms/embryology , Humans , Infant , Infant, Newborn , Male , Mediastinal Neoplasms/diagnostic imaging , Polyhydramnios/pathology , Pregnancy , Radiography , Retroperitoneal Neoplasms/diagnostic imaging , Sacrococcygeal Region/pathology , Teratoma/diagnostic imaging , Teratoma/embryology , Young Adult
11.
Cell ; 146(2): 209-21, 2011 Jul 22.
Article in English | MEDLINE | ID: mdl-21737130

ABSTRACT

Cancer cell of origin is difficult to identify by analyzing cells within terminal stage tumors, whose identity could be concealed by the acquired plasticity. Thus, an ideal approach to identify the cell of origin is to analyze proliferative abnormalities in distinct lineages prior to malignancy. Here, we use mosaic analysis with double markers (MADM) in mice to model gliomagenesis by initiating concurrent p53/Nf1 mutations sporadically in neural stem cells (NSCs). Surprisingly, MADM-based lineage tracing revealed significant aberrant growth prior to malignancy only in oligodendrocyte precursor cells (OPCs), but not in any other NSC-derived lineages or NSCs themselves. Upon tumor formation, phenotypic and transcriptome analyses of tumor cells revealed salient OPC features. Finally, introducing the same p53/Nf1 mutations directly into OPCs consistently led to gliomagenesis. Our findings suggest OPCs as the cell of origin in this model, even when initial mutations occur in NSCs, and highlight the importance of analyzing premalignant stages to identify the cancer cell of origin.


Subject(s)
Brain Neoplasms/genetics , Brain Neoplasms/pathology , Glioma/genetics , Glioma/pathology , Mosaicism , Neoplastic Stem Cells/pathology , Animals , Astrocytes/pathology , Biomarkers , Brain Neoplasms/embryology , Genes, p53 , Glioma/embryology , Mice , Molecular Sequence Data , Mutation , Neural Stem Cells/pathology , Neurofibromin 1/genetics , Neurons/pathology , Oligodendroglia/pathology
12.
Ultrasound Obstet Gynecol ; 38(6): 646-51, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21584889

ABSTRACT

OBJECTIVES: To describe the sonographic technique for assessment of the fetal optic nerve sheath and to report on three fetuses with intracranial lesions and enlarged optic nerve sheath diameter (ONSD) compared with normal controls matched for gestational age (GA). METHODS: In this cross-sectional study ONSD was measured sonographically in three fetuses (aged 23, 24 and 35 gestational weeks) with intracranial findings associated with increased intracranial pressure (ICP; dural thrombosis and intracranial tumors) as well as 42 healthy controls matched for GA ± 1 week (aged 22-25 and 34-36 weeks). For fetal eye assessment, transabdominal and transvaginal routes and high-resolution transducers were used for optimal visualization depending on fetal position. Measurements were made using an axial view at the level of the orbits, with the fetal face positioned towards the transducer. The ONSD was measured 1.5 or 2 mm behind the papilla (depending on GA) in all fetuses. Mean ± 2 SD ONSD of controls were calculated for each GA and compared with data from the three fetuses with intracranial pathology. RESULTS: In the 42 normal fetuses, ONSD increased from 1.2 mm at 23 weeks to 2.6 mm at 36 weeks. The measurements at 36 weeks correlated well with those observed in newborns. ONSD measurements of the three cases were above mean + 2 SD of values obtained from healthy controls at the same GA and also exceeded values of fetuses that were 1 week older. CONCLUSIONS: Fetal ONSD measurement is feasible using a technique similar to that used in adults and children. ONSD enlargement was observed in all three fetuses with intracranial lesions and may be an early tool with which to diagnose increased ICP.


Subject(s)
Brain Neoplasms/diagnostic imaging , Intracranial Hypertension/diagnostic imaging , Intracranial Thrombosis/diagnostic imaging , Myelin Sheath/diagnostic imaging , Nystagmus, Congenital/diagnostic imaging , Brain Neoplasms/embryology , Brain Neoplasms/pathology , Cross-Sectional Studies , Decision Making , Early Diagnosis , Female , Humans , Intracranial Hypertension/embryology , Intracranial Pressure , Intracranial Thrombosis/embryology , Intracranial Thrombosis/pathology , Nystagmus, Congenital/embryology , Nystagmus, Congenital/pathology , Optic Nerve/diagnostic imaging , Optic Nerve/pathology , Pregnancy , Prognosis , Ultrasonography
13.
Neurosurg Focus ; 27(2): E2, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19645558

ABSTRACT

The human insular cortex, or the lobus insularis, is considered the developmentally most primitive lobe of the telencephalon. Covered by an overlying cortical lid, the insula has functions that are distinct from yet related to those of the adjacent temporal lobe and deep limbic structures. In the first part of this paper the authors outline the development of the human insula, including the cellular heterogeneity comprising the various parts of the insular lobe. Using the understanding gained from the development of the insula they then address implications of insular development for cortical development and connection as well as for tumorigenesis and tumor spread from the insula to other cortical structures, most notably the temporal lobe. An understanding of cortico-insular development and interconnection allows for both a better understanding of insular pathology and also facilitates planning of resection of cortico-insular gliomas to avoid damage to eloquent structures.


Subject(s)
Brain Neoplasms/embryology , Brain Neoplasms/surgery , Cerebral Cortex/embryology , Glioma/surgery , Telencephalon/embryology , Brain Neoplasms/pathology , Cerebral Cortex/physiology , Cerebral Cortex/surgery , Diffusion Magnetic Resonance Imaging/statistics & numerical data , Glioblastoma/pathology , Glioma/diagnosis , Glioma/embryology , Humans , Models, Biological , Neocortex/embryology , Neocortex/surgery , Neoplastic Stem Cells/pathology , Neoplastic Stem Cells/physiology , Neural Pathways/anatomy & histology , Neural Pathways/surgery , Telencephalon/physiology , Telencephalon/surgery , Temporal Lobe/embryology , Temporal Lobe/surgery
14.
Prenat Diagn ; 29(4): 389-95, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19333960

ABSTRACT

Although no precise figures are available, many congenital brain lesions arise from intrauterine disruption, frequently due to obstetric complications. The most common entities include intracranial hemorrhage, ischemic lesions, thrombosis of venous vessels and infections. Accurate prenatal diagnosis is possible in many of these cases. However, the findings may be subtle, particularly in the early stage of the disruptive process. Identification of these conditions requires therefore specific expertise, the combination of fetal neurosonography and magnetic resonance, and frequently there is a need for serial examinations. Targeted diagnostic imaging should be offered to obstetric patients with conditions predisposing to prenatal cerebral insults.


Subject(s)
Brain Diseases/diagnosis , Brain Diseases/embryology , Fetal Diseases/diagnosis , Gestational Age , Prenatal Diagnosis , Blood Vessels/abnormalities , Blood Vessels/embryology , Brain/blood supply , Brain/embryology , Brain Diseases/etiology , Brain Neoplasms/diagnosis , Brain Neoplasms/embryology , Cytomegalovirus Infections/diagnosis , Cytomegalovirus Infections/embryology , Female , Humans , Hypoxia-Ischemia, Brain/diagnosis , Hypoxia-Ischemia, Brain/embryology , Infections/diagnosis , Infections/embryology , Intracranial Hemorrhages/diagnosis , Intracranial Hemorrhages/embryology , Pregnancy , Venous Thrombosis/diagnosis , Venous Thrombosis/embryology
15.
Endocr Pathol ; 20(2): 92-100, 2009.
Article in English | MEDLINE | ID: mdl-19377845

ABSTRACT

The neural crest is a pluripotent population of cells that arises at the junction of the neural tube and the dorsal ectoderm. These highly migratory cells form diverse derivatives including neurons and glia of the sensory, sympathetic, and enteric nervous systems, melanocytes, and the bones, cartilage, and connective tissues of the face. The neural crest has long been associated with the endocrine system, although not always correctly. According to current understanding, neural crest cells give rise to the chromaffin cells of the adrenal medulla, chief cells of the extra-adrenal paraganglia, and thyroid C cells. The endocrine tumors that correspond to these cell types are pheochromocytomas, extra-adrenal paragangliomas, and medullary thyroid carcinomas. Although controversies concerning embryological origin appear to have mostly been resolved, questions persist concerning the pathobiology of each tumor type and its basis in neural crest embryology. Here we present a brief history of the work on neural crest development, both in general and in application to the endocrine system. In particular, we present findings related to the plasticity and pluripotency of neural crest cells as well as a discussion of several different neural crest tumors in the endocrine system.


Subject(s)
Endocrine System/embryology , Neural Crest/physiology , Brain Neoplasms/embryology , Endocrine System/cytology , Humans , Neural Crest/cytology , Neuroendocrine Tumors/embryology , Neuronal Plasticity/physiology , Pluripotent Stem Cells/physiology
16.
Dev Biol ; 328(2): 257-72, 2009 Apr 15.
Article in English | MEDLINE | ID: mdl-19389366

ABSTRACT

The polycomb gene Bmi-1 is required for the self-renewal of stem cells from diverse tissues, including the central nervous system (CNS). Bmi-1 expression is elevated in most human gliomas, irrespective of grade, raising the question of whether Bmi-1 over-expression is sufficient to promote self-renewal or tumorigenesis by CNS stem/progenitor cells. To test this we generated Nestin-Bmi-1-GFP transgenic mice. Analysis of two independent lines with expression in the fetal and adult CNS demonstrated that transgenic neural stem cells formed larger colonies, more self-renewing divisions, and more neurons in culture. However, in vivo, Bmi-1 over-expression had little effect on CNS stem cell frequency, subventricular zone proliferation, olfactory bulb neurogenesis, or neurogenesis/gliogenesis during development. Bmi-1 transgenic mice were born with enlarged lateral ventricles and a minority developed idiopathic hydrocephalus as adults, but none of the transgenic mice formed detectable CNS tumors, even when aged. The more pronounced effects of Bmi-1 over-expression in culture were largely attributable to the attenuated induction of p16(Ink4a) and p19(Arf) in culture, proteins that are generally not expressed by neural stem/progenitor cells in young mice in vivo. Bmi-1 over-expression therefore has more pronounced effects in culture and does not appear to be sufficient to induce tumorigenesis in vivo.


Subject(s)
Brain/abnormalities , Neurogenesis/physiology , Neurons/metabolism , Nuclear Proteins/metabolism , Proto-Oncogene Proteins/metabolism , Repressor Proteins/metabolism , Stem Cells/metabolism , Animals , Brain/embryology , Brain/growth & development , Brain Neoplasms/embryology , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Proliferation , Cell Transformation, Neoplastic/metabolism , Cells, Cultured , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Glioma/embryology , Glioma/metabolism , Glioma/pathology , Humans , Hydrocephalus/embryology , Hydrocephalus/metabolism , Hydrocephalus/pathology , Intermediate Filament Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nerve Tissue Proteins/metabolism , Nestin , Neuroglia/cytology , Neuroglia/metabolism , Neurons/cytology , Nuclear Proteins/genetics , Polycomb Repressive Complex 1 , Proto-Oncogene Proteins/genetics , Repressor Proteins/genetics , Stem Cells/cytology
17.
Dev Biol ; 326(1): 224-36, 2009 Feb 01.
Article in English | MEDLINE | ID: mdl-19084514

ABSTRACT

The intrinsic neurons of mushroom bodies (MBs), centers of olfactory learning in the Drosophila brain, are generated by a specific set of neuroblasts (Nbs) that are born in the embryonic stage and exhibit uninterrupted proliferation till the end of the pupal stage. Whereas MB provides a unique model to study proliferation of neural progenitors, the underlying mechanism that controls persistent activity of MB-Nbs is poorly understood. Here we show that Tailless (TLL), a conserved orphan nuclear receptor, is required for optimum proliferation activity and prolonged maintenance of MB-Nbs and ganglion mother cells (GMCs). Mutations of tll progressively impair cell cycle in MB-Nbs and cause premature loss of MB-Nbs in the early pupal stage. TLL is also expressed in MB-GMCs to prevent apoptosis and promote cell cycling. In addition, we show that ectopic expression of tll leads to brain tumors, in which Prospero, a key regulator of progenitor proliferation and differentiation, is suppressed whereas localization of molecular components involved in asymmetric Nb division is unaffected. These results as a whole uncover a distinct regulatory mechanism of self-renewal and differentiation of the MB progenitors that is different from the mechanisms found in other progenitors.


Subject(s)
Cell Proliferation , DNA-Binding Proteins/physiology , Drosophila Proteins/physiology , Drosophila/embryology , Drosophila/growth & development , Mushroom Bodies/embryology , Mushroom Bodies/growth & development , Repressor Proteins/physiology , Animals , Apoptosis/physiology , Brain Neoplasms/embryology , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Cell Differentiation/physiology , DNA-Binding Proteins/genetics , Drosophila/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Ganglia, Invertebrate/embryology , Ganglia, Invertebrate/growth & development , Ganglia, Invertebrate/metabolism , Mushroom Bodies/metabolism , Mutation , Nerve Tissue Proteins/metabolism , Neurons/cytology , Neurons/physiology , Nuclear Proteins/metabolism , Repressor Proteins/genetics , Stem Cells/cytology , Stem Cells/physiology , Transcription Factors/metabolism
18.
Eur Radiol ; 18(10): 2060-6, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18458906

ABSTRACT

Fetal intracranial tumors are rare. The diagnosis is generally made on histology after birth. The aim of this study was to analyze clinical and imaging data in a series of fetal intracranial tumors and emphasize the findings that may help approach the diagnosis antenatally. We retrospectively analyzed imaging and clinical findings in 27 cases of fetal intracranial tumors assessed by ultrasound (27/27) and MR imaging (24/27). A histological diagnosis was always obtained. Main diagnoses included 15 germinal tumors (13 teratomas), 4 glial tumors, 2 craniopharyngiomas and 3 hamartomas. Average gestational age at diagnosis was 27 weeks for teratomas, 21 weeks for hamartomas and 34 weeks for glial tumors. All tumors but one were supra tentorial, and the lesion extended in the posterior fossa in two teratomas. A heterogeneous pattern, which was more frequently seen in teratomas, was better visualized by MR than US imaging. In addition, in two cases of teratomas, MR imaging better assessed the extension of the tumor. Teratomas and gliomas are the most frequent brain tumors in the fetus. US and MR imagings appear complementary in the prenatal assessment of these lesions.


Subject(s)
Brain Neoplasms/diagnosis , Brain Neoplasms/embryology , Fetal Diseases/diagnosis , Magnetic Resonance Imaging/methods , Ultrasonography, Prenatal/methods , Female , Humans , Male , Retrospective Studies
19.
Ultrasound Obstet Gynecol ; 28(7): 968-71, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17121422

ABSTRACT

We report the prenatal diagnosis of cerebellar cavernous angioma. Ultrasound examination at 21 weeks' gestation showed a hyperechogenic lesion measuring 12 mm in diameter, occupying most of the right cerebellar hemisphere. At 24 weeks' gestation, significant hypoplasia of the right hemisphere was diagnosed, and the pregnancy was terminated. Pathological evaluation of the lesion revealed extensive hemorrhaging and a rich network of dilated vessels and small capillaries. The right cerebellar lobe was hypoplastic and covered with blood clots. Cerebral cavernous malformation should be considered in the differential diagnosis of hyperechogenic lesions in the fetal cerebellum.


Subject(s)
Brain Neoplasms/diagnostic imaging , Cerebellum/abnormalities , Fetal Diseases/diagnostic imaging , Hemangioma, Cavernous/diagnostic imaging , Adult , Brain Neoplasms/embryology , Female , Humans , Infant, Newborn , Intracranial Hemorrhages/complications , Intracranial Hemorrhages/diagnostic imaging , Pregnancy , Prenatal Diagnosis , Ultrasonography, Prenatal/methods
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