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Kline-Fath BM. Fetal Skeletal Dysplasia. Magn Reson Imaging Clin N Am 2024; 32:497-511. [PMID: 38944437 DOI: 10.1016/j.mric.2024.02.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2024]
Abstract
Skeletal dysplasias (SDs) are a diverse group of genetic disorders. Diagnosis can be difficult as many are rare and with varied presentations, but with knowledge of the most common SDs presenting prenatal and with an algorithm that uses both sonographic and MR imaging techniques, directed genetic testing and counseling can be provided for many families.
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Affiliation(s)
- Beth M Kline-Fath
- Department of Radiology, M.L. 5031, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA.
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2
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Yang Z. The Principle of Cortical Development and Evolution. Neurosci Bull 2024:10.1007/s12264-024-01259-2. [PMID: 39023844 DOI: 10.1007/s12264-024-01259-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 06/21/2024] [Indexed: 07/20/2024] Open
Abstract
Human's robust cognitive abilities, including creativity and language, are made possible, at least in large part, by evolutionary changes made to the cerebral cortex. This paper reviews the biology and evolution of mammalian cortical radial glial cells (primary neural stem cells) and introduces the concept that a genetically step wise process, based on a core molecular pathway already in use, is the evolutionary process that has molded cortical neurogenesis. The core mechanism, which has been identified in our recent studies, is the extracellular signal-regulated kinase (ERK)-bone morphogenic protein 7 (BMP7)-GLI3 repressor form (GLI3R)-sonic hedgehog (SHH) positive feedback loop. Additionally, I propose that the molecular basis for cortical evolutionary dwarfism, exemplified by the lissencephalic mouse which originated from a larger gyrencephalic ancestor, is an increase in SHH signaling in radial glia, that antagonizes ERK-BMP7 signaling. Finally, I propose that: (1) SHH signaling is not a key regulator of primate cortical expansion and folding; (2) human cortical radial glial cells do not generate neocortical interneurons; (3) human-specific genes may not be essential for most cortical expansion. I hope this review assists colleagues in the field, guiding research to address gaps in our understanding of cortical development and evolution.
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Affiliation(s)
- Zhengang Yang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Department of Neurology, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
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3
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Sun M, Gao Y, Li Z, Yang L, Liu G, Xu Z, Guo R, You Y, Yang Z. ERK signaling expands mammalian cortical radial glial cells and extends the neurogenic period. Proc Natl Acad Sci U S A 2024; 121:e2314802121. [PMID: 38498715 PMCID: PMC10990156 DOI: 10.1073/pnas.2314802121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 02/12/2024] [Indexed: 03/20/2024] Open
Abstract
The molecular basis for cortical expansion during evolution remains largely unknown. Here, we report that fibroblast growth factor (FGF)-extracellular signal-regulated kinase (ERK) signaling promotes the self-renewal and expansion of cortical radial glial (RG) cells. Furthermore, FGF-ERK signaling induces bone morphogenic protein 7 (Bmp7) expression in cortical RG cells, which increases the length of the neurogenic period. We demonstrate that ERK signaling and Sonic Hedgehog (SHH) signaling mutually inhibit each other in cortical RG cells. We provide evidence that ERK signaling is elevated in cortical RG cells during development and evolution. We propose that the expansion of the mammalian cortex, notably in human, is driven by the ERK-BMP7-GLI3R signaling pathway in cortical RG cells, which participates in a positive feedback loop through antagonizing SHH signaling. We also propose that the relatively short cortical neurogenic period in mice is partly due to mouse cortical RG cells receiving higher SHH signaling that antagonizes ERK signaling.
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Affiliation(s)
- Mengge Sun
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Yanjing Gao
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Zhenmeiyu Li
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Lin Yang
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Guoping Liu
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Zhejun Xu
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Rongliang Guo
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Yan You
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
| | - Zhengang Yang
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, and Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai200032, China
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Shelkowitz E, Stence NV, Neuberger I, Park KL, Saenz MS, Pao E, Oyama N, Friedman SD, Shaw DWW, Mirzaa GM. Variants in PTEN Are Associated With a Diverse Spectrum of Cortical Dysplasia. Pediatr Neurol 2023; 147:154-162. [PMID: 37619436 DOI: 10.1016/j.pediatrneurol.2023.06.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 04/12/2023] [Accepted: 06/16/2023] [Indexed: 08/26/2023]
Abstract
BACKGROUND Inactivating mutations in PTEN are among the most common causes of megalencephaly. Activating mutations in other nodes of the PI3K/AKT/MTOR signaling pathway are recognized as a frequent cause of cortical brain malformations. Only recently has PTEN been associated with cortical malformations, and analyses of their prognostic significance have been limited. METHODS Retrospective neuroimaging analysis and detailed chart review were conducted on 20 participants identified with pathogenic or likely pathogenic mutations in PTEN and a cortical brain malformation present on brain magnetic resonance imaging. RESULTS Neuroimaging analysis revealed four main cerebral phenotypes-hemimegalencephaly, focal cortical dysplasia, polymicrogyria (PMG), and a less severe category, termed "macrocephaly with complicated gyral pattern" (MCG). Although a high proportion of participants (90%) had neurodevelopmental findings on presentation, outcomes varied and were favorable in over half of participants. Consistent with prior work, 39% of participants had autism spectrum disorder and 19% of participants with either pure-PMG or pure-MCG phenotypes had epilepsy. Megalencephaly and systemic overgrowth were common, but other systemic features of PTEN-hamartoma tumor syndrome were absent in over one-third of participants. CONCLUSIONS A spectrum of cortical dysplasias is present in individuals with inactivating mutations in PTEN. Future studies are needed to clarify the prognostic significance of each cerebral phenotype, but overall, we conclude that despite a high burden of neurodevelopmental disease, long-term outcomes may be favorable. Germline testing for PTEN mutations should be considered in cases of megalencephaly and cortical brain malformations even in the absence of other findings, including cognitive impairment.
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Affiliation(s)
- Emily Shelkowitz
- Department of Pediatrics, University of Washington, Seattle, Washington.
| | | | - Ilana Neuberger
- Department of Radiology, University of Colorado, Aurora, Colorado
| | - Kristen L Park
- Department of Pediatrics, University of Colorado, Aurora, Colorado
| | | | - Emily Pao
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - Nora Oyama
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - Seth D Friedman
- Department of Radiology, Seattle Children's Hospital, University of Washington, Seattle, Washington
| | - Dennis W W Shaw
- Department of Radiology, Seattle Children's Hospital, University of Washington, Seattle, Washington
| | - Ghayda M Mirzaa
- Department of Pediatrics, University of Washington, Seattle, Washington; Brotman Baty Institute for Precision Medicine, Seattle, Washington.
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5
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Krajden Haratz K, Birnbaum R, Kidron D, Har-Toov J, Salemnick Y, Brusilov M, Malinger G. Malformation of cortical development with abnormal cortex: early ultrasound diagnosis between 14 and 24 weeks of gestation. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2023; 61:559-565. [PMID: 36484522 DOI: 10.1002/uog.26139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/09/2022] [Accepted: 11/14/2022] [Indexed: 05/04/2023]
Abstract
OBJECTIVE To describe neurosonographic findings diagnostic or highly suggestive of the presence of malformations of cortical development involving the cortex that may be identified before 24 weeks of gestation. METHODS This was a retrospective single-center study of fetuses referred for neurosonography, during 2012-2019, with an abnormal cortical or sulcation pattern diagnosed early in the mid trimester. Stored files were analyzed for demographic data, abnormal brain findings, non-central nervous system abnormalities, final diagnosis and postnatal outcome. RESULTS The study cohort included 20 fetuses, with a mean gestational age at diagnosis of 18.7 (range, 14.4-23.6) weeks, in 11 of which the diagnosis was made before 20 weeks of gestation. Reasons for referral were: midline anomaly (n = 7), ventriculomegaly (n = 4), infratentorial findings (n = 3), suspected malformation of cortical development (n = 3), 'abnormal brain' (n = 2) and skeletal dysplasia (n = 1). On neurosonography, both the sulcation pattern and the cortical layer were abnormal in four cases, only the sulcation pattern was considered abnormal in seven and only the cortical layer was abnormal in nine. Nineteen fetuses presented with associated central nervous system anomalies and six also had non-central nervous system malformations. One case was recurrent. Eighteen parents opted for termination of pregnancy, including one selective termination in a twin pregnancy, and two fetuses were liveborn. CONCLUSIONS Familiarity with fetal brain anatomy and its early sonographic landmarks allowed early diagnosis of malformations involving cortical development. These patients are likely to represent the most severe cases and all had associated malformations. The presence of an abnormal cortical layer and/or abnormal overdeveloped sulci appear to be early signs of malformation of cortical development. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
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Affiliation(s)
- K Krajden Haratz
- Fetal Neurology Clinic, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - R Birnbaum
- Fetal Neurology Clinic, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - D Kidron
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Pathology, Meir Hospital, Kfar Saba, Israel
| | - J Har-Toov
- Fetal Neurology Clinic, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Y Salemnick
- Fetal Neurology Clinic, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - M Brusilov
- Fetal Neurology Clinic, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - G Malinger
- Fetal Neurology Clinic, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Ossola C, Kalebic N. Roots of the Malformations of Cortical Development in the Cell Biology of Neural Progenitor Cells. Front Neurosci 2022; 15:817218. [PMID: 35069108 PMCID: PMC8766818 DOI: 10.3389/fnins.2021.817218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 12/14/2021] [Indexed: 12/13/2022] Open
Abstract
The cerebral cortex is a structure that underlies various brain functions, including cognition and language. Mammalian cerebral cortex starts developing during the embryonic period with the neural progenitor cells generating neurons. Newborn neurons migrate along progenitors’ radial processes from the site of their origin in the germinal zones to the cortical plate, where they mature and integrate in the forming circuitry. Cell biological features of neural progenitors, such as the location and timing of their mitoses, together with their characteristic morphologies, can directly or indirectly regulate the abundance and the identity of their neuronal progeny. Alterations in the complex and delicate process of cerebral cortex development can lead to malformations of cortical development (MCDs). They include various structural abnormalities that affect the size, thickness and/or folding pattern of the developing cortex. Their clinical manifestations can entail a neurodevelopmental disorder, such as epilepsy, developmental delay, intellectual disability, or autism spectrum disorder. The recent advancements of molecular and neuroimaging techniques, along with the development of appropriate in vitro and in vivo model systems, have enabled the assessment of the genetic and environmental causes of MCDs. Here we broadly review the cell biological characteristics of neural progenitor cells and focus on those features whose perturbations have been linked to MCDs.
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Mimura PMP, Castro JTDSD, Jarry VDM, França Júnior MC, Reis F. New Magnetic Resonance Imaging (MRI) findings in a patient with hypochondroplasia caused by the FGFR3 N540K variant. ARQUIVOS DE NEURO-PSIQUIATRIA 2021; 79:656-657. [PMID: 34133497 DOI: 10.1590/0004-282x-anp-2020-0424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 10/07/2020] [Indexed: 11/21/2022]
Affiliation(s)
- Paula Maria Preto Mimura
- Pontifícia Universidade Católica de São Paulo, Faculdade de Medicina, Departamento de Reprodução Humana e Infância, Sorocaba, SP, Brazil
| | | | - Vinicius de Menezes Jarry
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas, Departamento de Radiologia, Campinas, SP, Brazil
| | | | - Fabiano Reis
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas, Departamento de Radiologia, Campinas, SP, Brazil
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Hickmott RA, Bosakhar A, Quezada S, Barresi M, Walker DW, Ryan AL, Quigley A, Tolcos M. The One-Stop Gyrification Station - Challenges and New Technologies. Prog Neurobiol 2021; 204:102111. [PMID: 34166774 DOI: 10.1016/j.pneurobio.2021.102111] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/31/2021] [Accepted: 06/18/2021] [Indexed: 12/12/2022]
Abstract
The evolution of the folded cortical surface is an iconic feature of the human brain shared by a subset of mammals and considered pivotal for the emergence of higher-order cognitive functions. While our understanding of the neurodevelopmental processes involved in corticogenesis has greatly advanced over the past 70 years of brain research, the fundamental mechanisms that result in gyrification, along with its originating cytoarchitectural location, remain largely unknown. This review brings together numerous approaches to this basic neurodevelopmental problem, constructing a narrative of how various models, techniques and tools have been applied to the study of gyrification thus far. After a brief discussion of core concepts and challenges within the field, we provide an analysis of the significant discoveries derived from the parallel use of model organisms such as the mouse, ferret, sheep and non-human primates, particularly with regard to how they have shaped our understanding of cortical folding. We then focus on the latest developments in the field and the complementary application of newly emerging technologies, such as cerebral organoids, advanced neuroimaging techniques, and atomic force microscopy. Particular emphasis is placed upon the use of novel computational and physical models in regard to the interplay of biological and physical forces in cortical folding.
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Affiliation(s)
- Ryan A Hickmott
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia; BioFab3D@ACMD, St Vincent's Hospital Melbourne, Fitzroy, VIC, 3065, Australia
| | - Abdulhameed Bosakhar
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia
| | - Sebastian Quezada
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia
| | - Mikaela Barresi
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia
| | - David W Walker
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia
| | - Amy L Ryan
- Hastings Centre for Pulmonary Research, Department of Pulmonary, Critical Care and Sleep Medicine, USC Keck School of Medicine, University of Southern California, CA, USA and Department of Stem Cell and Regenerative Medicine, University of Southern California, CA, 90033, USA
| | - Anita Quigley
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia; BioFab3D@ACMD, St Vincent's Hospital Melbourne, Fitzroy, VIC, 3065, Australia; School of Engineering, RMIT University, Melbourne, VIC, 3000, Australia; Department of Medicine, University of Melbourne, St Vincent's Hospital, Fitzroy, VIC, 3065, Australia; ARC Centre of Excellence in Electromaterials Science, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Mary Tolcos
- School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia.
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Boer LL, de Rooy L, Oostra RJ. Dutch teratological collections and their artistic portrayals. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2021; 187:283-295. [PMID: 33982861 PMCID: PMC8252381 DOI: 10.1002/ajmg.c.31902] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/24/2021] [Accepted: 03/14/2021] [Indexed: 12/18/2022]
Abstract
Several teratologic collections containing specimens with malformations and syndromes are maintained in a number of Dutch anatomical museums. Technically, these are not works of art or antiquities. However, many have been depicted in illustrations of such high quality that they merit discussion here. We review a selection of specimens and their artistic portrayals which find their origin in four Dutch teratological collections. These museum specimens are more than just intriguing objects for the inquisitive museum visitor. As we will substantiate, these specimens—and their artistic depictions—can be used to find and describe rarely occurring birth defects, provide etiopathogenetic information and are a source of novel diagnosis. Additionally, we briefly discuss the ethical aspects and motivations of exhibiting these specimens, as these collections have to be protected meticulously by the new generation of museum professionals, who eventually determine what kind of past our future will have. It is therefore imperative that these collections of antique specimens are treasured as their importance is easily overlooked.
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Affiliation(s)
- Lucas L Boer
- Department of Imaging, Section Anatomy and Museum for Anatomy and Pathology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Laurens de Rooy
- Department of Medical Biology, Sections Clinical Anatomy & Embryology and Museum Vrolik, Amsterdam University Hospitals - location Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Roelof-Jan Oostra
- Department of Medical Biology, Sections Clinical Anatomy & Embryology and Museum Vrolik, Amsterdam University Hospitals - location Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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10
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Choi JJ, Yang E, Soul JS, Jaimes C. Fetal magnetic resonance imaging: supratentorial brain malformations. Pediatr Radiol 2020; 50:1934-1947. [PMID: 33252760 DOI: 10.1007/s00247-020-04696-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 03/16/2020] [Accepted: 04/23/2020] [Indexed: 11/29/2022]
Abstract
Fetal MRI is the modality of choice to study supratentorial brain malformations. To accurately interpret the MRI, the radiologist needs to understand the normal sequence of events that occurs during prenatal brain development; this includes familiarity with the processes of hemispheric cleavage, formation of interhemispheric commissures, neuro-glial proliferation and migration, and cortical folding. Disruption of these processes results in malformations observed on fetal MRI including holoprosencephaly, callosal agenesis, heterotopic gray matter, lissencephaly and other malformations of cortical development (focal cortical dysplasia, polymicrogyria). The radiologist should also be familiar with findings that have high association with specific conditions affecting the central nervous system or other organ systems. This review summarizes and illustrates common patterns of supratentorial brain malformations and emphasizes aspects that are important to patient care.
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Affiliation(s)
- Jungwhan John Choi
- Department of Radiology, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA, USA
| | - Edward Yang
- Department of Radiology, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02115, USA.,Harvard Medical School, Boston, MA, USA
| | - Janet S Soul
- Harvard Medical School, Boston, MA, USA.,Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Camilo Jaimes
- Department of Radiology, Boston Children's Hospital, 300 Longwood Ave., Boston, MA, 02115, USA. .,Harvard Medical School, Boston, MA, USA. .,Fetal-Neonatal Neuroimaging and Developmental Science Center, Division of Newborn Medicine, Boston Children's Hospital, Boston, MA, USA.
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11
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Huang JY, Krebs BB, Miskus ML, Russell ML, Duffy EP, Graf JM, Lu HC. Enhanced FGFR3 activity in postmitotic principal neurons during brain development results in cortical dysplasia and axonal tract abnormality. Sci Rep 2020; 10:18508. [PMID: 33116259 PMCID: PMC7595096 DOI: 10.1038/s41598-020-75537-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 09/30/2020] [Indexed: 02/07/2023] Open
Abstract
Abnormal levels of fibroblast growth factors (FGFs) and FGF receptors (FGFRs) have been detected in various neurological disorders. The potent impact of FGF-FGFR in multiple embryonic developmental processes makes it challenging to elucidate their roles in postmitotic neurons. Taking an alternative approach to examine the impact of aberrant FGFR function on glutamatergic neurons, we generated a FGFR gain-of-function (GOF) transgenic mouse, which expresses constitutively activated FGFR3 (FGFR3K650E) in postmitotic glutamatergic neurons. We found that GOF disrupts mitosis of radial-glia neural progenitors (RGCs), inside-out radial migration of post-mitotic glutamatergic neurons, and axonal tract projections. In particular, late-born CUX1-positive neurons are widely dispersed throughout the GOF cortex. Such a cortical migration deficit is likely caused, at least in part, by a significant reduction of the radial processes projecting from RGCs. RNA-sequencing analysis of the GOF embryonic cortex reveals significant alterations in several pathways involved in cell cycle regulation and axonal pathfinding. Collectively, our data suggest that FGFR3 GOF in postmitotic neurons not only alters axonal growth of postmitotic neurons but also impairs RGC neurogenesis and radial glia processes.
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Affiliation(s)
- Jui-Yen Huang
- Department of Psychological and Brain Sciences, the Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, 1101 E. 10th Street, Bloomington, IN, 47405, USA.
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA.
| | - Bruna Baumgarten Krebs
- Department of Psychological and Brain Sciences, the Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, 1101 E. 10th Street, Bloomington, IN, 47405, USA
| | - Marisha Lynn Miskus
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
| | - May Lin Russell
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
| | - Eamonn Patrick Duffy
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
| | - Jason Michael Graf
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
| | - Hui-Chen Lu
- Department of Psychological and Brain Sciences, the Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, 1101 E. 10th Street, Bloomington, IN, 47405, USA.
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA.
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12
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Pascoe HM, Yang JYM, Chen J, Fink AM, Kumbla S. Macrocerebellum in Achondroplasia: A Further CNS Manifestation of FGFR3 Mutations? AJNR Am J Neuroradiol 2020; 41:338-342. [PMID: 31857328 DOI: 10.3174/ajnr.a6369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 11/02/2019] [Indexed: 12/29/2022]
Abstract
Achondroplasia is the result of a mutation in the fibroblast growth factor receptor 3 gene (FGFR3). Appearances suggestive of macrocerebellum have not been described in this patient group. We retrospectively reviewed MR imaging studies of the brain in 23 children with achondroplasia. A constellation of imaging findings that are recognized in macrocerebellum was observed, including cerebellar hemisphere enlargement (inferior and superior extension, wrapping around the brainstem); an effaced retro- and infravermian cerebellar subarachnoid CSF space; a shortened midbrain; distortion of the tectal plate; and mass effect on the brainstem. All MR imaging studies exhibited some of these findings. Quantitative analysis confirmed an increased cerebellar volume compared with age- and sex-matched controls. We hypothesized that this may be due to direct effects of the FGFR3 mutation on cerebellar morphogenesis.
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Affiliation(s)
- H M Pascoe
- From the Departments of Medical Imaging (H.M.P., A.M.F., S.K.)
| | - J Y-M Yang
- Neurosurgery (J.Y.-M.Y.), The Royal Children's Hospital, Parkville, Victoria, Australia
- Neuroscience Research (J.Y.-M.Y.)
- Developmental Imaging (J.Y.-M.Y., J.C.), Murdoch Children's Research Institute, Parkville, Victoria, Australia
- Department of Paediatrics (J.Y.-M.Y.), University of Melbourne, Parkville, Victoria, Australia
| | - J Chen
- Developmental Imaging (J.Y.-M.Y., J.C.), Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - A M Fink
- From the Departments of Medical Imaging (H.M.P., A.M.F., S.K.)
- Department of Perinatal Medicine (A.M.F.), Mercy Hospital for Women, Heidelberg, Victoria, Australia
| | - S Kumbla
- From the Departments of Medical Imaging (H.M.P., A.M.F., S.K.)
- Department of Diagnostic Imaging (S.K.), Monash Health, Clayton, Victoria, Australia
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13
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Assessment of genetic variant burden in epilepsy-associated brain lesions. Eur J Hum Genet 2019; 27:1738-1744. [PMID: 31358956 DOI: 10.1038/s41431-019-0484-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 06/29/2019] [Accepted: 07/05/2019] [Indexed: 01/31/2023] Open
Abstract
It is challenging to estimate genetic variant burden across different subtypes of epilepsy. Herein, we used a comparative approach to assess the genetic variant burden and genotype-phenotype correlations in four most common brain lesions in patients with drug-resistant focal epilepsy. Targeted sequencing analysis was performed for a panel of 161 genes with a mean coverage of >400×. Lesional tissue was histopathologically reviewed and dissected from hippocampal sclerosis (n = 15), ganglioglioma (n = 16), dysembryoplastic neuroepithelial tumors (n = 8), and focal cortical dysplasia type II (n = 15). Peripheral blood (n = 12) or surgical tissue samples histopathologically classified as lesion-free (n = 42) were available for comparison. Variants were classified as pathogenic or likely pathogenic according to American College of Medical Genetics and Genomics guidelines. Overall, we identified pathogenic and likely pathogenic variants in 25.9% of patients with a mean coverage of 383×. The highest number of pathogenic/likely pathogenic variants was observed in patients with ganglioglioma (43.75%; all somatic) and dysembryoplastic neuroepithelial tumors (37.5%; all somatic), and in 20% of cases with focal cortical dysplasia type II (13.33% somatic, 6.67% germline). Pathogenic/likely pathogenic positive genes were disorder specific and BRAF V600E the only recurrent pathogenic variant. This study represents a reference for the genetic variant burden across the four most common lesion entities in patients with drug-resistant focal epilepsy. The observed large variability in variant burden by epileptic lesion type calls for whole exome sequencing of histopathologically well-characterized tissue in a diagnostic setting and in research to discover novel disease-associated genes.
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14
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Tan AP, Priego G. Thanatophoric dysplasia type 1 with tectal plate dysplasia and aqueductal stenosis. Childs Nerv Syst 2019; 35:1059-1061. [PMID: 30610483 DOI: 10.1007/s00381-018-04035-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 12/17/2018] [Indexed: 10/27/2022]
Abstract
INTRODUCTION Skeletal dysplasias are a heterogeneous group of disorders comprising of more than 300 entities, many of which manifest in the prenatal period, emphasizing the importance of accurate prenatal diagnosis. Detection of a lethal skeletal dysplasia via prenatal ultrasound is often straightforward. However, establishing the specific diagnosis and detailed evaluation of intracranial anomalies are often challenging. Fetal magnetic resonance imaging (MRI) is superior to ultrasound in the detection of abnormal sulcation pattern, corpus callosal agenesis, and posterior fossa anomalies. Hence, it has the potential of delineating neuroimaging features that may not be fully elucidated by ultrasound. The objective of this article is to describe an unusual case of thanatophoric dysplasia (TD) with dysplastic tectal plate and resultant aqueductal stenosis diagnosed on fetal MRI. To the best of our knowledge, this has never been reported before in the literature. A comprehensive review of literature pertaining to TD-associated CNS abnormalities will also be included. CONCLUSIONS Our reported case adds to the current limited knowledge of this rare entity and emphasizes the crucial role of fetal MRI in expanding the neuroimaging phenotypes of TD.
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Affiliation(s)
- Ai Peng Tan
- Department of Diagnostic Imaging, National University Health System, 1E Kent Ridge Rd, Singapore, 119228, Singapore.
| | - Gema Priego
- Department of Radiology, Queen's Hospital, Rom Valley Way, Romford, RM7 0AG, UK
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15
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Jones WD, Guadiana SM, Grove EA. A model of neocortical area patterning in the lissencephalic mouse may hold for larger gyrencephalic brains. J Comp Neurol 2019; 527:1461-1477. [PMID: 30689213 DOI: 10.1002/cne.24643] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 12/21/2018] [Accepted: 01/02/2019] [Indexed: 12/14/2022]
Abstract
In the mouse, two telencephalic signaling centers orchestrate embryonic patterning of the cerebral cortex. From the rostral patterning center in the telencephalon, the Fibroblast Growth Factor, FGF8, disperses as a morphogen to establish the rostral to caudal axis of the neocortical area map. FGF8 coordinates with Wnt3a from the cortical hem to regulate graded expression of transcription factors that position neocortical areas, and control hippocampal development. Whether similar signaling centers pattern the much larger cortices of carnivore and primate species, however, is unclear. The limited dispersion range of FGF8 and Wnt3a is inconsistent with patterning larger cortical primordia. Yet the implication that different mechanisms organize cortex in different mammals flies in the face of the tenet that developmental patterning mechanisms are conserved across vertebrate species. In the present study, both signaling centers were identified in the ferret telencephalon, as were expression gradients of the patterning transcription factor genes regulated by FGF8 and Wnt3a. Notably, at the stage corresponding to the peak period of FGF8 signaling in the mouse neocortical primordium (NP), the NP was the same size in ferret and mouse, which would allow morphogen patterning of the ferret NP. Subsequently, the size of ferret neocortex shot past that of the mouse. Images from online databases further suggest that NP growth in humans, too, is slowed in early cortical development. We propose that if early growth in larger brains is held back, mechanisms that pattern the neocortical area map in the mouse could be conserved across mammalian species.
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Affiliation(s)
- William D Jones
- Department of Neurobiology, University of Chicago, Chicago, Illinois
| | - Sarah M Guadiana
- Department of Neurobiology, University of Chicago, Chicago, Illinois
| | - Elizabeth A Grove
- Department of Neurobiology, University of Chicago, Chicago, Illinois.,Committee on Development, Regeneration and Stem Cell Biology, University of Chicago, Chicago, Illinois.,Committee on Neurobiology, University of Chicago, Chicago, Illinois
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16
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Matsumoto N, Kobayashi N, Uda N, Hirota M, Kawasaki H. Pathophysiological analyses of leptomeningeal heterotopia using gyrencephalic mammals. Hum Mol Genet 2019; 27:985-991. [PMID: 29325060 DOI: 10.1093/hmg/ddy014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 01/03/2018] [Indexed: 12/16/2022] Open
Abstract
Leptomeningeal glioneuronal heterotopia (LGH) is a focal malformation of the cerebral cortex and frequently found in patients with thanatophoric dysplasia (TD). The pathophysiological mechanisms underlying LGH formation are still largely unclear because of difficulties in obtaining brain samples from human TD patients. Recently, we established a new animal model for analysing cortical malformations of human TD by utilizing our genetic manipulation technique for gyrencephalic carnivore ferrets. Here we investigated the pathophysiological mechanisms underlying the formation of LGH using our TD ferrets. We found that LGH was formed during corticogenesis in TD ferrets. Interestingly, we rarely found Ki-67-positive and phospho-histone H3-positive cells in LGH, suggesting that LGH formation does not involve cell proliferation. We uncovered that vimentin-positive radial glial fibers and doublecortin-positive migrating neurons were accumulated in LGH. This result may indicate that preferential cell migration into LGH underlies LGH formation. Our findings provide novel mechanistic insights into the pathogenesis of LGH in TD.
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Affiliation(s)
- Naoyuki Matsumoto
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan
| | - Naoki Kobayashi
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan.,Medical Research Training Program, School of Medicine, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan
| | - Natsu Uda
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan.,Medical Research Training Program, School of Medicine, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan
| | - Miwako Hirota
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan.,Medical Research Training Program, School of Medicine, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan
| | - Hiroshi Kawasaki
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan
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17
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Juric-Sekhar G, Hevner RF. Malformations of Cerebral Cortex Development: Molecules and Mechanisms. ANNUAL REVIEW OF PATHOLOGY 2019; 14:293-318. [PMID: 30677308 PMCID: PMC6938687 DOI: 10.1146/annurev-pathmechdis-012418-012927] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Malformations of cortical development encompass heterogeneous groups of structural brain anomalies associated with complex neurodevelopmental disorders and diverse genetic and nongenetic etiologies. Recent progress in understanding the genetic basis of brain malformations has been driven by extraordinary advances in DNA sequencing technologies. For example, somatic mosaic mutations that activate mammalian target of rapamycin signaling in cortical progenitor cells during development are now recognized as the cause of hemimegalencephaly and some types of focal cortical dysplasia. In addition, research on brain development has begun to reveal the cellular and molecular bases of cortical gyrification and axon pathway formation, providing better understanding of disorders involving these processes. New neuroimaging techniques with improved resolution have enhanced our ability to characterize subtle malformations, such as those associated with intellectual disability and autism. In this review, we broadly discuss cortical malformations and focus on several for which genetic etiologies have elucidated pathogenesis.
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Affiliation(s)
- Gordana Juric-Sekhar
- Department of Pathology, University of Washington School of Medicine, Seattle, Washington 98195, USA; ,
- Department of Neurological Surgery, University of Washington School of Medicine, Seattle, Washington 98195, USA
| | - Robert F Hevner
- Department of Pathology, University of Washington School of Medicine, Seattle, Washington 98195, USA; ,
- Department of Neurological Surgery, University of Washington School of Medicine, Seattle, Washington 98195, USA
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington 98105, USA
- Current affiliation: Department of Pathology, University of California, San Diego, California 92093, USA
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18
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Soo-Kyeong J, Lee N, Bae MH, Han YM, Hee Park K, Byun SY. Chylous Ascites in an Infant with Thanatophoric Dysplasia Type I with FGFR3 Mutation Surviving Five Months. Fetal Pediatr Pathol 2018; 37:363-371. [PMID: 30252581 DOI: 10.1080/15513815.2018.1504843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
BACKGROUND Thanatophoric dysplasia (TD) results from sporadic de novo mutations in the FGFR3 gene. Upon confirming intrauterine diagnosis of this perinatal disease, pregnancy termination is recommended. There is limited information on the natural history of longer-term survivors with type 1 TD. CASE REPORT A full-term neonate was confirmed via postnatal genetic testing to have type 1 TD. At 28 days, chylous ascites developed. Medium-chain triglyceride use improved the ascites. Cerebral ventriculomegaly worsened throughout life. Death due to respiratory failure occurred at age 5 months. CONCLUSION The chylous ascites in this child with type 1 TD and survival past the neonatal stage suggests that type 1 TD may be accompanied by abnormalities of the lymphatic channels. Moreover, ventriculomegaly can be progressive.
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Affiliation(s)
- Jeon Soo-Kyeong
- a Department of Pediatrics , Pusan National University Children's Hospital , Yangsan , Korea.,b Department of Pediatrics , Pusan National University School of Medicine , Busan , Korea
| | - Narae Lee
- a Department of Pediatrics , Pusan National University Children's Hospital , Yangsan , Korea.,b Department of Pediatrics , Pusan National University School of Medicine , Busan , Korea
| | - Mi Hye Bae
- b Department of Pediatrics , Pusan National University School of Medicine , Busan , Korea.,c Department of Pediatrics , Pusan National University School of Medicine , Yangsan , Korea
| | - Young Mi Han
- a Department of Pediatrics , Pusan National University Children's Hospital , Yangsan , Korea.,b Department of Pediatrics , Pusan National University School of Medicine , Busan , Korea
| | - Kyung Hee Park
- b Department of Pediatrics , Pusan National University School of Medicine , Busan , Korea.,c Department of Pediatrics , Pusan National University School of Medicine , Yangsan , Korea
| | - Shin Yun Byun
- a Department of Pediatrics , Pusan National University Children's Hospital , Yangsan , Korea.,b Department of Pediatrics , Pusan National University School of Medicine , Busan , Korea
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19
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Kawasaki H. Molecular Investigations of the Development and Diseases of Cerebral Cortex Folding using Gyrencephalic Mammal Ferrets. Biol Pharm Bull 2018; 41:1324-1329. [DOI: 10.1248/bpb.b18-00142] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Hiroshi Kawasaki
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University
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20
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Elsen GE, Bedogni F, Hodge RD, Bammler TK, MacDonald JW, Lindtner S, Rubenstein JLR, Hevner RF. The Epigenetic Factor Landscape of Developing Neocortex Is Regulated by Transcription Factors Pax6→ Tbr2→ Tbr1. Front Neurosci 2018; 12:571. [PMID: 30186101 PMCID: PMC6113890 DOI: 10.3389/fnins.2018.00571] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 07/30/2018] [Indexed: 12/12/2022] Open
Abstract
Epigenetic factors (EFs) regulate multiple aspects of cerebral cortex development, including proliferation, differentiation, laminar fate, and regional identity. The same neurodevelopmental processes are also regulated by transcription factors (TFs), notably the Pax6→ Tbr2→ Tbr1 cascade expressed sequentially in radial glial progenitors (RGPs), intermediate progenitors, and postmitotic projection neurons, respectively. Here, we studied the EF landscape and its regulation in embryonic mouse neocortex. Microarray and in situ hybridization assays revealed that many EF genes are expressed in specific cortical cell types, such as intermediate progenitors, or in rostrocaudal gradients. Furthermore, many EF genes are directly bound and transcriptionally regulated by Pax6, Tbr2, or Tbr1, as determined by chromatin immunoprecipitation-sequencing and gene expression analysis of TF mutant cortices. Our analysis demonstrated that Pax6, Tbr2, and Tbr1 form a direct feedforward genetic cascade, with direct feedback repression. Results also revealed that each TF regulates multiple EF genes that control DNA methylation, histone marks, chromatin remodeling, and non-coding RNA. For example, Tbr1 activates Rybp and Auts2 to promote the formation of non-canonical Polycomb repressive complex 1 (PRC1). Also, Pax6, Tbr2, and Tbr1 collectively drive massive changes in the subunit isoform composition of BAF chromatin remodeling complexes during differentiation: for example, a novel switch from Bcl7c (Baf40c) to Bcl7a (Baf40a), the latter directly activated by Tbr2. Of 11 subunits predominantly in neuronal BAF, 7 were transcriptionally activated by Pax6, Tbr2, or Tbr1. Using EFs, Pax6→ Tbr2→ Tbr1 effect persistent changes of gene expression in cell lineages, to propagate features such as regional and laminar identity from progenitors to neurons.
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Affiliation(s)
- Gina E. Elsen
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Francesco Bedogni
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Rebecca D. Hodge
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Theo K. Bammler
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, United States
| | - James W. MacDonald
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, United States
| | - Susan Lindtner
- Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA, United States
- Department of Psychiatry, University of California, San Francisco, San Francisco, CA, United States
| | - John L. R. Rubenstein
- Nina Ireland Laboratory of Developmental Neurobiology, University of California, San Francisco, San Francisco, CA, United States
- Department of Psychiatry, University of California, San Francisco, San Francisco, CA, United States
| | - Robert F. Hevner
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
- Department of Neurological Surgery, School of Medicine, University of Washington, Seattle, WA, United States
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21
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Bal-Price A, Hogberg HT, Crofton KM, Daneshian M, FitzGerald RE, Fritsche E, Heinonen T, Hougaard Bennekou S, Klima S, Piersma AH, Sachana M, Shafer TJ, Terron A, Monnet-Tschudi F, Viviani B, Waldmann T, Westerink RHS, Wilks MF, Witters H, Zurich MG, Leist M. Recommendation on test readiness criteria for new approach methods in toxicology: Exemplified for developmental neurotoxicity. ALTEX-ALTERNATIVES TO ANIMAL EXPERIMENTATION 2018; 35:306-352. [PMID: 29485663 DOI: 10.14573/altex.1712081] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 01/29/2018] [Indexed: 01/06/2023]
Abstract
Multiple non-animal-based test methods have never been formally validated. In order to use such new approach methods (NAMs) in a regulatory context, criteria to define their readiness are necessary. The field of developmental neurotoxicity (DNT) testing is used to exemplify the application of readiness criteria. The costs and number of untested chemicals are overwhelming for in vivo DNT testing. Thus, there is a need for inexpensive, high-throughput NAMs, to obtain initial information on potential hazards, and to allow prioritization for further testing. A background on the regulatory and scientific status of DNT testing is provided showing different types of test readiness levels, depending on the intended use of data from NAMs. Readiness criteria, compiled during a stakeholder workshop, uniting scientists from academia, industry and regulatory authorities are presented. An important step beyond the listing of criteria, was the suggestion for a preliminary scoring scheme. On this basis a (semi)-quantitative analysis process was assembled on test readiness of 17 NAMs with respect to various uses (e.g. prioritization/screening, risk assessment). The scoring results suggest that several assays are currently at high readiness levels. Therefore, suggestions are made on how DNT NAMs may be assembled into an integrated approach to testing and assessment (IATA). In parallel, the testing state in these assays was compiled for more than 1000 compounds. Finally, a vision is presented on how further NAM development may be guided by knowledge of signaling pathways necessary for brain development, DNT pathophysiology, and relevant adverse outcome pathways (AOP).
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Affiliation(s)
- Anna Bal-Price
- European Commission, Joint Research Centre (EC JRC), Ispra (VA), Italy
| | - Helena T Hogberg
- Center for Alternatives to Animal Testing (CAAT), Johns Hopkins University, Baltimore, MD, USA
| | - Kevin M Crofton
- National Centre for Computational Toxicology, US EPA, RTP, Washington, NC, USA
| | - Mardas Daneshian
- Center for Alternatives to Animal Testing, CAAT-Europe, University of Konstanz, Konstanz, Germany
| | - Rex E FitzGerald
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland
| | - Ellen Fritsche
- IUF - Leibniz Research Institute for Environmental Medicine & Heinrich-Heine-University, Düsseldorf, Germany
| | - Tuula Heinonen
- Finnish Centre for Alternative Methods (FICAM), University of Tampere, Tampere, Finland
| | | | - Stefanie Klima
- In vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Konstanz, Germany
| | - Aldert H Piersma
- RIVM, National Institute for Public Health and the Environment, Bilthoven, and Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Magdalini Sachana
- Organisation for Economic Co-operation and Development (OECD), Paris, France
| | - Timothy J Shafer
- National Centre for Computational Toxicology, US EPA, RTP, Washington, NC, USA
| | | | - Florianne Monnet-Tschudi
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland.,Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Barbara Viviani
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Italy
| | - Tanja Waldmann
- In vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Konstanz, Germany
| | - Remco H S Westerink
- Neurotoxicology Research Group, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Martin F Wilks
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland
| | - Hilda Witters
- VITO, Flemish Institute for Technological Research, Unit Environmental Risk and Health, Mol, Belgium
| | - Marie-Gabrielle Zurich
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland.,Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Marcel Leist
- Center for Alternatives to Animal Testing, CAAT-Europe, University of Konstanz, Konstanz, Germany.,In vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Konstanz, Germany
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22
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Chen CP, Chang TY, Lin TW, Chern SR, Chen SW, Lai ST, Chuang TY, Wang W. Prenatal diagnosis of hydrancephaly and enlarged cerebellum and cisterna magna in a fetus with thanatophoric dysplasia type II and a review of prenatal diagnosis of brain anomalies associated with thanatophoric dysplasia. Taiwan J Obstet Gynecol 2018; 57:119-122. [PMID: 29458880 DOI: 10.1016/j.tjog.2017.12.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2017] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVE We present prenatal diagnosis of hydrancephaly and enlarged cerebellum and cisterna magna in a fetus with thanatophoric dysplasia type II (TD2) and a review of prenatal diagnosis of brain anomalies associated with TD. CASE REPORT A 33-year-old woman was referred for genetic counseling at 25 weeks of gestation because of fetal ultrasound abnormalities. Prenatal ultrasound at 14 weeks of gestation revealed an increased nuchal translucency (NT) and hydrocephalus. Level II ultrasound examination at 25 weeks of gestation revealed hydrancephaly, macrocephaly, a cloverleaf skull, frontal bossing, enlarged cerebellum and cisterna magna, a narrow chest, small ribs, short straight limbs. Amniocentesis revealed a karyotype of 46,XX. FGFR3 mutation analysis using the DNA extracted from uncultured amniocytes revealed a genotype of WT/c.1948A>G (p.Lys650Glu). The result was consistent with a K650E mutation in FGFR3 and TD2. The pregnancy was subsequently terminated. CONCLUSION Fetuses with TD2 may present increased NT, early onset hydrocephalus, enlarged cerebellum and cisterna magna, and hydrancephaly on prenatal ultrasound.
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Affiliation(s)
- Chih-Ping Chen
- Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan; Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Medicine, Mackay Medical College, New Taipei City, Taiwan; Department of Biotechnology, Asia University, Taichung, Taiwan; School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan.
| | | | | | - Schu-Rern Chern
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan
| | - Shin-Wen Chen
- Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Shih-Ting Lai
- Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Tzu-Yun Chuang
- Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan
| | - Wayseen Wang
- Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan; Department of Bioengineering, Tatung University, Taipei, Taiwan
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23
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Tan AP, Mankad K. Apert syndrome: magnetic resonance imaging (MRI) of associated intracranial anomalies. Childs Nerv Syst 2018; 34:205-216. [PMID: 29198073 DOI: 10.1007/s00381-017-3670-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 11/20/2017] [Indexed: 01/21/2023]
Abstract
INTRODUCTION Apert syndrome is one of the most common craniosynostosis syndrome caused by mutations in genes encoding fibroblast growth factor receptor 2 (FGFR2). It is characterized by multisuture craniosynostosis, midfacial hypoplasia, abnormal skull base development and syndactyly of all extremities. Apert syndrome is associated with a wide array of central nervous system (CNS) anomalies, possibly the cause of the common occurrence of mental deficiency in patients with Apert syndrome. These CNS anomalies can be broadly classified into two groups; (1) those that are primary malformations and (2) those that occur secondary to osseous deformity/malformation. CONCLUSION Familiarity with CNS anomalies associated with Apert syndrome is important to both clinicians and radiologist as it impacts on management and prognostication. Cognitive development of patients has been linked to associated CNS anomalies, timing of surgery and social aspects. These associated anomalies can be broadly classified into (1) those that are primary malformations and (2) those that occur secondary to osseous deformity/malformation, as illustrated in our review paper.
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Affiliation(s)
- Ai Peng Tan
- Department of Diagnostic Radiology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore.
| | - Kshitij Mankad
- Department of Neuroradiology, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
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24
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Manikkam SA, Chetcuti K, Howell KB, Savarirayan R, Fink AM, Mandelstam SA. Temporal Lobe Malformations in Achondroplasia: Expanding the Brain Imaging Phenotype Associated with FGFR3-Related Skeletal Dysplasias. AJNR Am J Neuroradiol 2017; 39:380-384. [PMID: 29170271 DOI: 10.3174/ajnr.a5468] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 09/13/2017] [Indexed: 11/07/2022]
Abstract
Thanatophoric dysplasia, achondroplasia, and hypochondroplasia belong to the fibroblast growth factor receptor 3 (FGFR3) group of genetic skeletal disorders. Temporal lobe abnormalities have been documented in thanatophoric dysplasia and hypochondroplasia, and in 1 case of achondroplasia. We retrospectively identified 13 children with achondroplasia who underwent MR imaging of the brain between 2002 and 2015. All children demonstrated a deep transverse temporal sulcus on MR imaging. Further common neuroimaging findings were incomplete hippocampal rotation (12 children), oversulcation of the mesial temporal lobe (11 children), loss of gray-white matter differentiation of the mesial temporal lobe (5 children), and a triangular shape of the temporal horn (6 children). These appearances are very similar to those described in hypochondroplasia, strengthening the association of temporal lobe malformations in FGFR3-associated skeletal dysplasias.
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Affiliation(s)
- S A Manikkam
- From the Departments of Medical Imaging (S.A. Manikkam, A.M.F., S.A. Mandelstam)
| | - K Chetcuti
- Department of Radiology (K.C.), Alder Hey Children's Hospital, Liverpool, UK
| | - K B Howell
- Neurology (K.B.H.), Royal Children's Hospital, Melbourne, Australia.,Departments of Paediatrics (K.B.H., S.A. Mandelstam).,Murdoch Children's Research Institute (K.B.H., R.S., A.M.F., S.A. Mandelstam), Melbourne, Australia
| | - R Savarirayan
- Murdoch Children's Research Institute (K.B.H., R.S., A.M.F., S.A. Mandelstam), Melbourne, Australia.,Victorian Clinical Genetics Services (R.S.), Melbourne, Australia
| | - A M Fink
- From the Departments of Medical Imaging (S.A. Manikkam, A.M.F., S.A. Mandelstam).,Radiology (A.M.F., S.A. Mandelstam), University of Melbourne, Melbourne, Australia.,Murdoch Children's Research Institute (K.B.H., R.S., A.M.F., S.A. Mandelstam), Melbourne, Australia
| | - S A Mandelstam
- From the Departments of Medical Imaging (S.A. Manikkam, A.M.F., S.A. Mandelstam).,Departments of Paediatrics (K.B.H., S.A. Mandelstam).,Radiology (A.M.F., S.A. Mandelstam), University of Melbourne, Melbourne, Australia.,Murdoch Children's Research Institute (K.B.H., R.S., A.M.F., S.A. Mandelstam), Melbourne, Australia.,Florey Institute of Neuroscience and Mental Health (S.A. Mandelstam), Melbourne, Australia
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25
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Goldstein IS, Erickson DJ, Sleeper LA, Haynes RL, Kinney HC. The Lateral Temporal Lobe in Early Human Life. J Neuropathol Exp Neurol 2017; 76:424-438. [PMID: 28498956 DOI: 10.1093/jnen/nlx026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Abnormalities of lateral temporal lobe development are associated with a spectrum of genetic and environmental pathologic processes, but more normative data are needed for a better understanding of gyrification in this brain region. Here, we begin to establish guidelines for the analysis of the lateral temporal lobe in humans in early life. We present quantitative methods for measuring gyrification at autopsy using photographs of the gross brain and simple computer-based quantitative tools in a cohort of 28 brains ranging in age from 27 to 70 postconceptional weeks (end of infancy). We provide normative ranges for different indices of gyrification and identify a constellation of qualitative features that should also be considered in these analyses. The ratio of the temporal area to the whole brain area increased dramatically in the second half of gestation, but then decelerated after birth before increasing linearly around 50 postconceptional weeks. Tertiary gyrification continued beyond birth in a linear process through infancy with considerable variation in patterns. Analysis of 2 brains with gyral disorders of the lateral temporal lobe demonstrated proof-of-principle that the proposed methods are of diagnostic value. These guidelines are proposed for assessments of temporal lobe pathology in pediatric brains in early life.
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Affiliation(s)
- Isabel S Goldstein
- From the Department of Pathology, Boston Children's Hospital and Harvard Medical School (ISG, DJE, RLH, HCK); and Department of Cardiology, Boston Children's Hospital and Harvard Medical School, Boston, MA (LAS)
| | - Drexel J Erickson
- From the Department of Pathology, Boston Children's Hospital and Harvard Medical School (ISG, DJE, RLH, HCK); and Department of Cardiology, Boston Children's Hospital and Harvard Medical School, Boston, MA (LAS)
| | - Lynn A Sleeper
- From the Department of Pathology, Boston Children's Hospital and Harvard Medical School (ISG, DJE, RLH, HCK); and Department of Cardiology, Boston Children's Hospital and Harvard Medical School, Boston, MA (LAS)
| | - Robin L Haynes
- From the Department of Pathology, Boston Children's Hospital and Harvard Medical School (ISG, DJE, RLH, HCK); and Department of Cardiology, Boston Children's Hospital and Harvard Medical School, Boston, MA (LAS)
| | - Hannah C Kinney
- From the Department of Pathology, Boston Children's Hospital and Harvard Medical School (ISG, DJE, RLH, HCK); and Department of Cardiology, Boston Children's Hospital and Harvard Medical School, Boston, MA (LAS)
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26
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Hatakeyama J, Sato H, Shimamura K. Developing guinea pig brain as a model for cortical folding. Dev Growth Differ 2017; 59:286-301. [PMID: 28585227 DOI: 10.1111/dgd.12371] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/05/2017] [Accepted: 05/06/2017] [Indexed: 12/31/2022]
Abstract
The cerebral cortex in mammals, the neocortex specifically, is highly diverse among species with respect to its size and morphology, likely reflecting the immense adaptiveness of this lineage. In particular, the pattern and number of convoluted ridges and fissures, called gyri and sulci, respectively, on the surface of the cortex are variable among species and even individuals. However, little is known about the mechanism of cortical folding, although there have been several hypotheses proposed. Recent studies on embryonic neurogenesis revealed the differences in cortical progenitors as a critical factor of the process of gyrification. Here, we investigated the gyrification processes using developing guinea pig brains that form a simple but fundamental pattern of gyri. In addition, we established an electroporation-mediated gene transfer method for guinea pig embryos. We introduce the guinea pig brain as a useful model system to understand the mechanisms and basic principle of cortical folding.
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Affiliation(s)
- Jun Hatakeyama
- Department of Brain Morphogenesis, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Haruka Sato
- Department of Brain Morphogenesis, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Kenji Shimamura
- Department of Brain Morphogenesis, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
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27
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Matsumoto N, Hoshiba Y, Morita K, Uda N, Hirota M, Minamikawa M, Ebisu H, Shinmyo Y, Kawasaki H. Pathophysiological analyses of periventricular nodular heterotopia using gyrencephalic mammals. Hum Mol Genet 2017; 26:1173-1181. [PMID: 28158406 DOI: 10.1093/hmg/ddx038] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 01/24/2017] [Indexed: 12/13/2022] Open
Abstract
Although periventricular nodular heterotopia (PNH) is often found in the cerebral cortex of people with thanatophoric dysplasia (TD), the pathophysiology of PNH in TD is largely unknown. This is mainly because of difficulties in obtaining brain samples of TD patients and a lack of appropriate animal models for analyzing the pathophysiology of PNH in TD. Here we investigate the pathophysiological mechanisms of PNH in the cerebral cortex of TD by utilizing a ferret TD model which we recently developed. To make TD ferrets, we electroporated fibroblast growth factor 8 (FGF8) into the cerebral cortex of ferrets. Our immunohistochemical analyses showed that PNH nodules in the cerebral cortex of TD ferrets were mostly composed of cortical neurons, including upper layer neurons and GABAergic neurons. We also found disorganizations of radial glial fibers and of the ventricular lining in the TD ferret cortex, indicating that PNH may result from defects in radial migration of cortical neurons along radial glial fibers during development. Our findings provide novel mechanistic insights into the pathogenesis of PNH in TD.
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Affiliation(s)
- Naoyuki Matsumoto
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University
| | - Yoshio Hoshiba
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University
| | - Kazuya Morita
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University.,Medical Research Training Program, School of Medicine, Kanazawa University
| | - Natsu Uda
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University.,Medical Research Training Program, School of Medicine, Kanazawa University
| | - Miwako Hirota
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University.,Medical Research Training Program, School of Medicine, Kanazawa University
| | - Maki Minamikawa
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University.,Medical Research Training Program, School of Medicine, Kanazawa University
| | - Haruka Ebisu
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University
| | - Yohei Shinmyo
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University
| | - Hiroshi Kawasaki
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University.,Brain/Liver Interface Medicine Research Center, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan
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28
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Heng X, Guo Q, Leung AW, Li JY. Analogous mechanism regulating formation of neocortical basal radial glia and cerebellar Bergmann glia. eLife 2017; 6. [PMID: 28489004 PMCID: PMC5457141 DOI: 10.7554/elife.23253] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 05/09/2017] [Indexed: 12/29/2022] Open
Abstract
Neocortical basal radial glia (bRG) and cerebellar Bergmann glia (BG) are basal progenitors derived from ventricular apical radial glia (aRG) that selectively lose their apical processes. bRG and BG have been implicated in the expansion and folding of the cerebrum and cerebellum, respectively. Here, we analyzed the molecular characteristics and development of bRG and BG. Transcriptomic comparison revealed striking similarity of the molecular features of bRG and BG. We found that heightened ERK signaling activity in aRG is tightly linked to the temporal formation and the relative abundance of bRG in human and mouse cortices. Forced activation of an FGF-ERK-ETV axis that is crucial to BG induction specifically induced bRG with canonical human bRG features in mice. Therefore, our data point to a common mechanism of bRG and BG generation, bearing implications to the role for these basal progenitors in the evolution of cortical folding of the cerebrum and cerebellum. DOI:http://dx.doi.org/10.7554/eLife.23253.001 The outer layer of the brain of a mammal, called the cortex, helps support mental abilities such as memory, attention and thought. In rodents, the cortex is smooth whereas in primates it is organized into folds. These folds increase the surface area of the brain and thus the number of neurons it can contain, which may in turn increase its processing power. Folding occurs as the brain develops in the womb. Specialized cells called basal or outer radial glia, which are more abundant in humans than in rodents, are believed to trigger the folding process. Another area of the brain, called the cerebellum, is intricately folded in both rodents and humans. As the brain develops, cells within the cerebellum called Bergmann glia cause the tissue to fold. Bergmann glia and basal radial glia share a number of similarities, but it was not known whether the same molecular pathway might regulate both types of cell. Now, Heng et al. show that Bergmann glia in the cerebellums of mice and basal radial glia in human cortex contain similar sets of active genes. Moreover, the molecular pathway that gives rise to Bergmann glia in mice is also active in the cortex of both mice and humans. However, it is much more active in humans, leading Heng et al. to speculate that high levels of activity in this pathway might give rise to basal radial glia. Consistent with this prediction, artificially activating the pathway at high levels in mouse cortex triggered the formation of basal radial glia in mice too. These results thus suggest that a common mechanism generates both types of glial cells involved in brain folding. The work of Heng et al. lays the foundations for further studies into how these cells fold the brain and thus how they contribute to more complex mental abilities. Remaining questions to address are whether other species with Bergmann glia also have folded cerebellums, and whether incorrect development of basal radial glia in humans leads to disorders in which the cortex folds abnormally. DOI:http://dx.doi.org/10.7554/eLife.23253.002
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Affiliation(s)
- Xin Heng
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States
| | - Qiuxia Guo
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States
| | - Alan W Leung
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States
| | - James Yh Li
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States.,Institute for Systems Genomics, University of Connecticut, Farmington, United States
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29
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KAWASAKI H. Molecular investigations of development and diseases of the brain of higher mammals using the ferret. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2017; 93:259-269. [PMID: 28496051 PMCID: PMC5489433 DOI: 10.2183/pjab.93.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/14/2017] [Indexed: 06/07/2023]
Abstract
The brains of higher mammals such as primates and carnivores contain well-developed unique brain structures. Uncovering the physiological functions, developmental mechanisms and evolution of these brain structures would greatly facilitate our understanding of the human brain and its diseases. Although the anatomical and electrophysiological features of these brain structures have been intensively investigated, our knowledge about their molecular bases is still limited. To overcome this limitation, genetic techniques for the brains of carnivores and primates have been established, and molecules whose expression patterns correspond to these brain structures were identified recently. To investigate the functional roles of these molecules, rapid and efficient genetic manipulation methods for higher mammals have been explored. In this review, recent advances in molecular investigations of the brains of higher mammals are discussed, mainly focusing on ferrets (Mustela putorius furo).
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Affiliation(s)
- Hiroshi KAWASAKI
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Ishikawa, Japan
- Brain/Liver Interface Medicine Research Center, Kanazawa University, Ishikawa, Japan
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30
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Wagner MW, Poretti A, Benson JE, Huisman TAGM. Neuroimaging Findings in Pediatric Genetic Skeletal Disorders: A Review. J Neuroimaging 2016; 27:162-209. [PMID: 28000960 DOI: 10.1111/jon.12413] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 11/01/2016] [Indexed: 12/15/2022] Open
Abstract
Genetic skeletal disorders (GSDs) are a heterogeneous group characterized by an intrinsic abnormality in growth and (re-)modeling of cartilage and bone. A large subgroup of GSDs has additional involvement of other structures/organs beside the skeleton, such as the central nervous system (CNS). CNS abnormalities have an important role in long-term prognosis of children with GSDs and should consequently not be missed. Sensitive and specific identification of CNS lesions while evaluating a child with a GSD requires a detailed knowledge of the possible associated CNS abnormalities. Here, we provide a pattern-recognition approach for neuroimaging findings in GSDs guided by the obvious skeletal manifestations of GSD. In particular, we summarize which CNS findings should be ruled out with each GSD. The diseases (n = 180) are classified based on the skeletal involvement (1. abnormal metaphysis or epiphysis, 2. abnormal size/number of bones, 3. abnormal shape of bones and joints, and 4. abnormal dynamic or structural changes). For each disease, skeletal involvement was defined in accordance with Online Mendelian Inheritance in Man. Morphological CNS involvement has been described based on extensive literature search. Selected examples will be shown based on prevalence of the diseases and significance of the CNS involvement. CNS involvement is common in GSDs. A wide spectrum of morphological abnormalities is associated with GSDs. Early diagnosis of CNS involvement is important in the management of children with GSDs. This pattern-recognition approach aims to assist and guide physicians in the diagnostic work-up of CNS involvement in children with GSDs and their management.
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Affiliation(s)
- Matthias W Wagner
- Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD.,Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland
| | - Andrea Poretti
- Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Jane E Benson
- Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD
| | - Thierry A G M Huisman
- Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, MD
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31
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Abstract
Studies of syndromic hydrocephalus have led to the identification of >100 causative genes. Even though this work has illuminated numerous pathways associated with hydrocephalus, it has also highlighted the fact that the genetics underlying this phenotype are more complex than anticipated originally. Mendelian forms of hydrocephalus account for a small fraction of the genetic burden, with clear evidence of background-dependent effects of alleles on penetrance and expressivity of driver mutations in key developmental and homeostatic pathways. Here, we synthesize the currently implicated genes and inheritance paradigms underlying hydrocephalus, grouping causal loci into functional modules that affect discrete, albeit partially overlapping, cellular processes. These in turn have the potential to both inform pathomechanism and assist in the rational molecular classification of a clinically heterogeneous phenotype. Finally, we discuss conceptual methods that can lead to enhanced gene identification and dissection of disease basis, knowledge that will potentially form a foundation for the design of future therapeutics.
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Affiliation(s)
- Maria Kousi
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina 27701;
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina 27701;
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32
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Tully HM, Ishak GE, Rue TC, Dempsey JC, Browd SR, Millen KJ, Doherty D, Dobyns WB. Two Hundred Thirty-Six Children With Developmental Hydrocephalus: Causes and Clinical Consequences. J Child Neurol 2016; 31:309-20. [PMID: 26184484 PMCID: PMC4990005 DOI: 10.1177/0883073815592222] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 05/23/2015] [Indexed: 11/15/2022]
Abstract
Few systematic assessments of developmental forms of hydrocephalus exist. We reviewed magnetic resonance images (MRIs) and clinical records of patients with infancy-onset hydrocephalus. Among 411 infants, 236 had hydrocephalus with no recognizable extrinsic cause. These children were assigned to 1 of 5 subtypes and compared on the basis of clinical characteristics and developmental and surgical outcomes. At an average age of 5.3 years, 72% of children were walking independently and 87% could eat by mouth; in addition, 18% had epilepsy. Distinct patterns of associated malformations and syndromes were observed within each subtype. On average, children with aqueductal obstruction, cysts, and encephaloceles had worse clinical outcomes than those with other forms of developmental hydrocephalus. Overall, 53% of surgically treated patients experienced at least 1 shunt failure, but hydrocephalus associated with posterior fossa crowding required fewer shunt revisions. We conclude that each subtype of developmental hydrocephalus is associated with distinct clinical characteristics, syndromology, and outcomes, suggesting differences in underlying mechanisms.
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Affiliation(s)
- Hannah M Tully
- Department of Neurology, University of Washington, Seattle, WA, USA Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Gisele E Ishak
- Department of Radiology, University of Washington, Seattle, WA, USA
| | - Tessa C Rue
- Department of Biostatistics, University of Washington, Seattle, WA, USA
| | | | - Samuel R Browd
- Department of Neurological Surgery, University of Washington, Seattle, WA, USA Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Kathleen J Millen
- Department of Pediatrics, University of Washington, Seattle, WA, USA Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Dan Doherty
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - William B Dobyns
- Department of Neurology, University of Washington, Seattle, WA, USA Department of Pediatrics, University of Washington, Seattle, WA, USA Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
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33
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Pathophysiological analyses of cortical malformation using gyrencephalic mammals. Sci Rep 2015; 5:15370. [PMID: 26482531 PMCID: PMC4613358 DOI: 10.1038/srep15370] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 09/23/2015] [Indexed: 12/12/2022] Open
Abstract
One of the most prominent features of the cerebral cortex of higher mammals is the presence of gyri. Because malformations of the cortical gyri are associated with severe disability in brain function, the mechanisms underlying malformations of the cortical gyri have been of great interest. Combining gyrencephalic carnivore ferrets and genetic manipulations using in utero electroporation, here we successfully recapitulated the cortical phenotypes of thanatophoric dysplasia (TD) by expressing fibroblast growth factor 8 in the ferret cerebral cortex. Strikingly, in contrast to TD mice, our TD ferret model showed not only megalencephaly but also polymicrogyria. We further uncovered that outer radial glial cells (oRGs) and intermediate progenitor cells (IPs) were markedly increased. Because it has been proposed that increased oRGs and/or IPs resulted in the appearance of cortical gyri during evolution, it seemed possible that increased oRGs and IPs underlie the pathogenesis of polymicrogyria. Our findings should help shed light on the molecular mechanisms underlying the formation and malformation of cortical gyri in higher mammals.
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34
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Congenital and Acquired Conditions of the Mesial Temporal Lobe: A Pictorial Essay. Can Assoc Radiol J 2015; 66:238-51. [DOI: 10.1016/j.carj.2014.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 12/04/2014] [Accepted: 12/10/2014] [Indexed: 11/18/2022] Open
Abstract
Purpose Our goal is to pictorially review a wide spectrum of congenital and acquired conditions affecting the medial aspect of the temporal lobe. Conclusion After completing this article, the reader will have knowledge of the imaging appearance of diverse developmental, malformative, and acquired lesions of the mesial temporal lobe, which will be useful when evaluating pathology in this location.
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35
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Sarnat HB, Philippart M, Flores-Sarnat L, Wei XC. Timing in neural maturation: arrest, delay, precociousness, and temporal determination of malformations. Pediatr Neurol 2015; 52:473-86. [PMID: 25797487 DOI: 10.1016/j.pediatrneurol.2015.01.020] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 01/29/2015] [Accepted: 01/31/2015] [Indexed: 11/30/2022]
Abstract
Timing is primordial in initiating and synchronizing each developmental process in tissue morphogenesis. Maturational arrest, delay, and precociousness all are conducive to neurological dysfunction and may determine different malformations depending on when in development the faulty timing occurred, regardless of the identification of a specific genetic mutation or an epigenetic teratogenic event. Delay and arrest are distinguished by whether further progressive development over time can be expected or the condition is static. In general, retardation of early developmental processes, such as neurulation, cellular proliferation, and migration, leads to maturational arrest. Retardation of late processes, such as synaptogenesis and myelination, are more likely to result in maturational delay. Faulty timing of neuronal maturation in relation to other developmental processes causes neurological dysfunction and abnormal electroencephalograph maturation in preterm neonates. Precocious synaptogenesis, including pruning to provide plasticity, may facilitate prenatal formation of epileptic circuitry leading to severe postnatal infantile epilepsies. The anterior commissure forms 3 weeks earlier than the corpus callosum; its presence or absence in callosal agenesis is a marker for the onset of the initial insult. An excessively thick corpus callosum may be due to delayed retraction of transitory collateral axons. Malformations that arise at different times can share a common pathogenesis with variations on the extent: timing of mitotic cycles in mosaic somatic mutations may distinguish hemimegalencephaly from focal cortical dysplasia type 2. Timing should always be considered in interpreting cerebral dysgeneses in both imaging and neuropathological diagnoses.
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Affiliation(s)
- Harvey B Sarnat
- Department of Paediatrics, University of Calgary Faculty of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada; Department of Pathology (Neuropathology), University of Calgary Faculty of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada; Department of Clinical Neurosciences, University of Calgary Faculty of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada.
| | | | - Laura Flores-Sarnat
- Department of Paediatrics, University of Calgary Faculty of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada; Department of Clinical Neurosciences, University of Calgary Faculty of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
| | - Xing-Chang Wei
- Department of Paediatrics, University of Calgary Faculty of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada; Department of Radiology and Diagnostic Imaging, University of Calgary Faculty of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
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36
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de Juan Romero C, Bruder C, Tomasello U, Sanz-Anquela JM, Borrell V. Discrete domains of gene expression in germinal layers distinguish the development of gyrencephaly. EMBO J 2015; 34:1859-74. [PMID: 25916825 PMCID: PMC4547892 DOI: 10.15252/embj.201591176] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 03/27/2015] [Indexed: 12/28/2022] Open
Abstract
Gyrencephalic species develop folds in the cerebral cortex in a stereotypic manner, but the genetic mechanisms underlying this patterning process are unknown. We present a large-scale transcriptomic analysis of individual germinal layers in the developing cortex of the gyrencephalic ferret, comparing between regions prospective of fold and fissure. We find unique transcriptional signatures in each germinal compartment, where thousands of genes are differentially expressed between regions, including ∼80% of genes mutated in human cortical malformations. These regional differences emerge from the existence of discrete domains of gene expression, which occur at multiple locations across the developing cortex of ferret and human, but not the lissencephalic mouse. Complex expression patterns emerge late during development and map the eventual location of folds or fissures. Protomaps of gene expression within germinal layers may contribute to define cortical folds or functional areas, but our findings demonstrate that they distinguish the development of gyrencephalic cortices.
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Affiliation(s)
- Camino de Juan Romero
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain
| | - Carl Bruder
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Ugo Tomasello
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain
| | | | - Víctor Borrell
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas & Universidad Miguel Hernández, Sant Joan d'Alacant, Spain
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37
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Stoos C, Nelsen L, Schissler KA, Elliott AJ, Kinney HC. Fetal alcohol syndrome and secondary schizophrenia: a unique neuropathologic study. J Child Neurol 2015; 30:601-5. [PMID: 24563476 PMCID: PMC8312346 DOI: 10.1177/0883073814520976] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We report the unique neuropathologic study of an adult brain of a patient with fetal alcohol syndrome who developed the well-recognized complication of schizophrenia in adolescence. The major finding was asymmetric formation of the lateral temporal lobes, with marked enlargement of the right superior temporal gyrus, suggesting that alcohol is preferentially toxic to temporal lobe patterning during gestation. Critical maturational changes unique to adolescence can unmask psychotic symptomatology mediated by temporal lobe pathology that has been clinically dormant since birth. Elucidating the neuropathologic basis of the secondary psychiatric disorders in fetal alcohol syndrome can help provide insight into their putative developmental origins.
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Affiliation(s)
- Catherine Stoos
- Department of Pathology, Sanford Health, Sioux Falls, SD, USA
| | - Laura Nelsen
- Department of Pathology, MaineGeneral Health, Augusta, MA, USA
| | - Kathryn A Schissler
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, MA, USA
| | - Amy J Elliott
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, MA, USA
| | - Hannah C Kinney
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, MA, USA
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38
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Abstract
Thanatophoric dysplasia (TD) is a lethal form of skeletal dysplasia with short-limb dwarfism. Two types distinguished with their radiological characteristics have been defined clinically. The femur is curved in type 1, while it is straight in type 2. TD is known to be due to a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. We report a male patient who showed clinical findings congruent with TD type 2 and a new mutation in the FGFR3 gene, a finding which has not been reported previously.
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Affiliation(s)
- Selvi Gülaşı
- Mersin University Faculty of Medicine, Department of Pediatrics, Mersin, Turkey. E-mail:
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39
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Abstract
Disorders of brain overgrowth are significant causes of intractable epilepsy, intellectual disability, autism, and other complex neurological problems. The pathology of these disorders is sometimes striking and characteristic, as in hemimegalencephaly, but can also be subtle, as in autism. Recent genetic studies have shown that many diverse forms of brain overgrowth are caused by de novo mutations that increase activity in the receptor tyrosine kinase (RTK)-phosphatidylinositol-3-kinase (PI3K)-AKT signaling pathway, a key mediator of signaling by growth factors in the developing brain, such as fibroblast growth factors. In cases where mutations arise in postzygotic embryos, brain regions exhibit mosaic pathology that reflects the distribution of mutant cells, ranging from focal cortical dysplasia to lobar or hemispheric overgrowth. In turn, the histopathology of these disorders is also remarkably varied. The common underlying mechanisms of RTK-PI3K-AKT overactivation suggest new possibilities for drugs that inhibit this pathway.
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Affiliation(s)
- Robert F. Hevner
- Departments of Neurological Surgery and Pathology, University of Washington School of Medicine, Seattle, WA
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40
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Stark Z, McGillivray G, Sampson A, Palma-Dias R, Edwards A, Said JM, Whiteley G, Fink AM. Apert syndrome: temporal lobe abnormalities on fetal brain imaging. Prenat Diagn 2014; 35:179-82. [DOI: 10.1002/pd.4515] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 09/08/2014] [Accepted: 10/04/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Zornitza Stark
- Victorian Clinical Genetics Services; Murdoch Children's Research Institute; Melbourne Australia
- Fetal Medicine Unit; Royal Women's Hospital; Melbourne Australia
- Maternal Fetal Medicine, Sunshine Hospital; Western Health; Melbourne Australia
| | - George McGillivray
- Victorian Clinical Genetics Services; Murdoch Children's Research Institute; Melbourne Australia
- Fetal Medicine Unit; Royal Women's Hospital; Melbourne Australia
| | - Amanda Sampson
- Fetal Medicine Unit; Royal Women's Hospital; Melbourne Australia
- Pauline Gandell Women's Imaging Centre; The Royal Women's Hospital; Melbourne Australia
| | - Ricardo Palma-Dias
- Fetal Medicine Unit; Royal Women's Hospital; Melbourne Australia
- Pauline Gandell Women's Imaging Centre; The Royal Women's Hospital; Melbourne Australia
- Pregnancy Research Centre, Department of Obstetrics and Gynaecology; University of Melbourne; Melbourne Australia
| | - Andrew Edwards
- Fetal Diagnostic Unit; Monash Medical Centre; Melbourne Australia
- The Ritchie Centre; Monash Institute of Medical Research; Melbourne Australia
| | - Joanne M. Said
- Fetal Medicine Unit; Royal Women's Hospital; Melbourne Australia
- Maternal Fetal Medicine, Sunshine Hospital; Western Health; Melbourne Australia
- NorthWest Academic Centre; The University of Melbourne; Melbourne Australia
| | - Gillian Whiteley
- Department of Radiology; Monash Medical Centre; Melbourne Australia
| | - A. Michelle Fink
- Fetal Medicine Unit; Royal Women's Hospital; Melbourne Australia
- Department of Radiology; University of Melbourne; Melbourne Australia
- Medical Imaging Department; The Royal Children's Hospital; Melbourne Australia
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41
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Wang DC, Shannon P, Toi A, Chitayat D, Mohan U, Barkova E, Keating S, Tomlinson G, Glanc P. Temporal lobe dysplasia: a characteristic sonographic finding in thanatophoric dysplasia. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2014; 44:588-594. [PMID: 24585534 DOI: 10.1002/uog.13337] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 02/03/2014] [Accepted: 02/11/2014] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To determine the incidence of temporal lobe dysplasia (TLD) detected on prenatal ultrasound in thanatophoric dysplasia (TD) over an 11-year period in a tertiary referral center. METHODS An 11-year retrospective review of perinatal autopsies from 2002 to 2013 was performed to identify cases of TD. The ultrasound images and corresponding reports of all TD cases were examined for the presence of TLD. The same set of images subsequently underwent a retrospective review by a perinatal radiologist with knowledge of the features of TLD to determine whether they could be identified. RESULTS Thirty-one cases of TD underwent perinatal autopsy, and prenatal ultrasound imaging was available for review in 24 (77%). Mean gestational age at diagnosis of TD was 21.3 (range, 18-36) weeks. TLD was identified and reported in 6/24 (25%) cases; all six cases occurred after 2007. Retrospective interpretation of the ultrasound images identified features of TLD in 10 additional cases. In total, 16/24 (67%) cases displayed sonographic evidence of TLD. Temporal trends showed that TLD features were present in 50% (5/10) of all TD cases between 2002 and 2006 and in 79% (11/14) of those detected between 2007 and 2013. CONCLUSIONS At present, the detection rate of TLD by ultrasound is low but may be increased by modified brain images that enhance visualization of the temporal lobes. Prenatal identification of TLD may help in the prenatal diagnosis of TD and thus provide more accurate prenatal counseling and guide molecular investigations to confirm the specific diagnosis of TD.
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Affiliation(s)
- D C Wang
- Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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42
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Tully HM, Dobyns WB. Infantile hydrocephalus: a review of epidemiology, classification and causes. Eur J Med Genet 2014; 57:359-68. [PMID: 24932902 PMCID: PMC4334358 DOI: 10.1016/j.ejmg.2014.06.002] [Citation(s) in RCA: 199] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 06/02/2014] [Indexed: 12/19/2022]
Abstract
Hydrocephalus is a common but complex condition caused by physical or functional obstruction of CSF flow that leads to progressive ventricular dilatation. Though hydrocephalus was recently estimated to affect 1.1 in 1000 infants, there have been few systematic assessments of the causes of hydrocephalus in this age group, which makes it a challenging condition to approach as a scientist or as a clinician. Here, we review contemporary literature on the epidemiology, classification and pathogenesis of infantile hydrocephalus. We describe the major environmental and genetic causes of hydrocephalus, with the goal of providing a framework to assess infants with hydrocephalus and guide future research.
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Affiliation(s)
- Hannah M Tully
- Department of Neurology, University of Washington, Seattle, WA, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA.
| | - William B Dobyns
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
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43
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Mayoral ÉE, Schultz R, Rosemberg S, Suzuki L, de Oliveira LAN, Kay FU. Thanatophoric dysplasia: case report of an autopsy complemented by postmortem computed tomographic study. AUTOPSY AND CASE REPORTS 2014; 4:35-41. [PMID: 28580325 PMCID: PMC5448300 DOI: 10.4322/acr.2014.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 06/19/2014] [Indexed: 12/27/2022] Open
Abstract
Thanatophoric dysplasia (TD) is one of the most common lethal skeletal dysplasias, which was first designated as thanatophoric dwarfism and described in 1967. The authors report a case of a Caucasian girl with TD, born to a 31-year-old woman without comorbidities. The newborn presented respiratory distress immediately after delivery, progressing to death in less than 2 hours. An autopsy was carried out after postmortem tomographic examination. The autopsy findings depicted extensive malformations of the skeletal system and the brain. The aim of this report is to discuss the pathogenesis and correlate the morphologic features of TD that were disclosed at the tomography and the autopsy.
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Affiliation(s)
- Éber Emanuel Mayoral
- Pathological Anatomical Division - Hospital das Clínicas - Faculdade de Medicina - Universidade de São Paulo, São Paulo/SP, Brazil
| | - Regina Schultz
- Pathological Anatomical Division - Hospital das Clínicas - Faculdade de Medicina - Universidade de São Paulo, São Paulo/SP, Brazil
| | - Sérgio Rosemberg
- Department of Pathology - Faculdade de Medicina - Universidade de São Paulo, São Paulo/SP, Brazil
| | - Lisa Suzuki
- Institute of Child - Faculdade de Medicina - Universidade de São Paulo, São Paulo/SP, Brazil
| | | | - Fernando Uliana Kay
- Institute of Child - Faculdade de Medicina - Universidade de São Paulo, São Paulo/SP, Brazil
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44
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Cesaretti C, Spaccini L, Rustico M, Parazzini C, Doneda C, Re TJ, Righini A. Prenatal magnetic resonance imaging detection of temporal lobes and hippocampal anomalies in hypochondroplasia. Prenat Diagn 2014; 34:1015-7. [DOI: 10.1002/pd.4415] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 05/14/2014] [Accepted: 05/14/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Claudia Cesaretti
- Radiology and Neuroradiology Department; Children's Hospital V. Buzzi; Milan Italy
- Medical Genetics Unit, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico; Milan Italy
| | - Luigina Spaccini
- Obstetrics and Gynecology Department; Children's Hospital V. Buzzi; Milan Italy
| | - Mariangela Rustico
- Obstetrics and Gynecology Department; Children's Hospital V. Buzzi; Milan Italy
| | - Cecilia Parazzini
- Radiology and Neuroradiology Department; Children's Hospital V. Buzzi; Milan Italy
| | - Chiara Doneda
- Radiology and Neuroradiology Department; Children's Hospital V. Buzzi; Milan Italy
| | - Thomas J. Re
- Radiology Institute; University of Milan; Milan Italy
| | - Andrea Righini
- Radiology and Neuroradiology Department; Children's Hospital V. Buzzi; Milan Italy
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45
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Abstract
Malformations of cortical development are common causes of developmental delay and epilepsy. Some patients have early, severe neurological impairment, but others have epilepsy or unexpected deficits that are detectable only by screening. The rapid evolution of molecular biology, genetics, and imaging has resulted in a substantial increase in knowledge about the development of the cerebral cortex and the number and types of malformations reported. Genetic studies have identified several genes that might disrupt each of the main stages of cell proliferation and specification, neuronal migration, and late cortical organisation. Many of these malformations are caused by de-novo dominant or X-linked mutations occurring in sporadic cases. Genetic testing needs accurate assessment of imaging features, and familial distribution, if any, and can be straightforward in some disorders but requires a complex diagnostic algorithm in others. Because of substantial genotypic and phenotypic heterogeneity for most of these genes, a comprehensive analysis of clinical, imaging, and genetic data is needed to properly define these disorders. Exome sequencing and high-field MRI are rapidly modifying the classification of these disorders.
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Affiliation(s)
- Renzo Guerrini
- Department of Neuroscience, Pharmacology and Child Health, Children's Hospital A Meyer and University of Florence, Florence, Italy; Stella Maris Foundation Research Institute, Pisa, Italy.
| | - William B Dobyns
- Departments of Pediatrics and Neurology, University of Washington, Seattle, WA, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
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46
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Sun T, Hevner RF. Growth and folding of the mammalian cerebral cortex: from molecules to malformations. Nat Rev Neurosci 2014; 15:217-32. [PMID: 24646670 DOI: 10.1038/nrn3707] [Citation(s) in RCA: 338] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The size and extent of folding of the mammalian cerebral cortex are important factors that influence a species' cognitive abilities and sensorimotor skills. Studies in various animal models and in humans have provided insight into the mechanisms that regulate cortical growth and folding. Both protein-coding genes and microRNAs control cortical size, and recent progress in characterizing basal progenitor cells and the genes that regulate their proliferation has contributed to our understanding of cortical folding. Neurological disorders linked to disruptions in cortical growth and folding have been associated with novel neurogenetic mechanisms and aberrant signalling pathways, and these findings have changed concepts of brain evolution and may lead to new medical treatments for certain disorders.
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Affiliation(s)
- Tao Sun
- Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, BOX 60, New York, New York 10065, USA
| | - Robert F Hevner
- Department of Neurological Surgery and Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington 98101, USA
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47
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Miller JA, Ding SL, Sunkin SM, Smith KA, Ng L, Szafer A, Ebbert A, Riley ZL, Royall JJ, Aiona K, Arnold JM, Bennet C, Bertagnolli D, Brouner K, Butler S, Caldejon S, Carey A, Cuhaciyan C, Dalley RA, Dee N, Dolbeare TA, Facer BAC, Feng D, Fliss TP, Gee G, Goldy J, Gourley L, Gregor BW, Gu G, Howard RE, Jochim JM, Kuan CL, Lau C, Lee CK, Lee F, Lemon TA, Lesnar P, McMurray B, Mastan N, Mosqueda N, Naluai-Cecchini T, Ngo NK, Nyhus J, Oldre A, Olson E, Parente J, Parker PD, Parry SE, Stevens A, Pletikos M, Reding M, Roll K, Sandman D, Sarreal M, Shapouri S, Shapovalova NV, Shen EH, Sjoquist N, Slaughterbeck CR, Smith M, Sodt AJ, Williams D, Zöllei L, Fischl B, Gerstein MB, Geschwind DH, Glass IA, Hawrylycz MJ, Hevner RF, Huang H, Jones AR, Knowles JA, Levitt P, Phillips JW, Sestan N, Wohnoutka P, Dang C, Bernard A, Hohmann JG, Lein ES. Transcriptional landscape of the prenatal human brain. Nature 2014; 508:199-206. [PMID: 24695229 PMCID: PMC4105188 DOI: 10.1038/nature13185] [Citation(s) in RCA: 862] [Impact Index Per Article: 86.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 02/26/2014] [Indexed: 12/21/2022]
Abstract
The anatomical and functional architecture of the human brain is largely determined by prenatal transcriptional processes. We describe an anatomically comprehensive atlas of mid-gestational human brain, including de novo reference atlases, in situ hybridization, ultra-high resolution magnetic resonance imaging (MRI) and microarray analysis on highly discrete laser microdissected brain regions. In developing cerebral cortex, transcriptional differences are found between different proliferative and postmitotic layers, wherein laminar signatures reflect cellular composition and developmental processes. Cytoarchitectural differences between human and mouse have molecular correlates, including species differences in gene expression in subplate, although surprisingly we find minimal differences between the inner and human-expanded outer subventricular zones. Both germinal and postmitotic cortical layers exhibit fronto-temporal gradients, with particular enrichment in frontal lobe. Finally, many neurodevelopmental disorder and human evolution-related genes show patterned expression, potentially underlying unique features of human cortical formation. These data provide a rich, freely-accessible resource for understanding human brain development.
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Affiliation(s)
- Jeremy A Miller
- 1] Allen Institute for Brain Science, Seattle, Washington 98103, USA [2]
| | - Song-Lin Ding
- 1] Allen Institute for Brain Science, Seattle, Washington 98103, USA [2]
| | - Susan M Sunkin
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Kimberly A Smith
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Lydia Ng
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Aaron Szafer
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Amanda Ebbert
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Zackery L Riley
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Joshua J Royall
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Kaylynn Aiona
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - James M Arnold
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Crissa Bennet
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | | | - Krissy Brouner
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Stephanie Butler
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Shiella Caldejon
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Anita Carey
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | | | - Rachel A Dalley
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Nick Dee
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Tim A Dolbeare
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | | | - David Feng
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Tim P Fliss
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Garrett Gee
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Jeff Goldy
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Lindsey Gourley
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | | | - Guangyu Gu
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Robert E Howard
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Jayson M Jochim
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Chihchau L Kuan
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Christopher Lau
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Chang-Kyu Lee
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Felix Lee
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Tracy A Lemon
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Phil Lesnar
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Bergen McMurray
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Naveed Mastan
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Nerick Mosqueda
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Theresa Naluai-Cecchini
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, 1959 North East Pacific Street, Box 356320, Seattle, Washington 98195, USA
| | - Nhan-Kiet Ngo
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Julie Nyhus
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Aaron Oldre
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Eric Olson
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Jody Parente
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Patrick D Parker
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Sheana E Parry
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Allison Stevens
- 1] Department of Radiology, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA [2] Computer Science and AI Lab, MIT, Cambridge, Massachusetts 02139, USA
| | - Mihovil Pletikos
- Department of Neurobiology and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut 06510, USA
| | - Melissa Reding
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Kate Roll
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - David Sandman
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Melaine Sarreal
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Sheila Shapouri
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | | | - Elaine H Shen
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Nathan Sjoquist
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | | | - Michael Smith
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Andy J Sodt
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Derric Williams
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Lilla Zöllei
- Department of Radiology, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
| | - Bruce Fischl
- 1] Department of Radiology, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA [2] Computer Science and AI Lab, MIT, Cambridge, Massachusetts 02139, USA
| | - Mark B Gerstein
- 1] Program in Computational Biology and Bioinformatics, Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA [2] Department of Computer Science, Yale University, New Haven, Connecticut 06520, USA
| | - Daniel H Geschwind
- Program in Neurogenetics, Department of Neurology and Semel Institute David Geffen School of Medicine, UCLA, Los Angeles, California 90095, USA
| | - Ian A Glass
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, 1959 North East Pacific Street, Box 356320, Seattle, Washington 98195, USA
| | | | - Robert F Hevner
- 1] Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington 98101, USA [2] Department of Neurological Surgery, University of Washington School of Medicine, Seattle, Washington 98105, USA
| | - Hao Huang
- Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Allan R Jones
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - James A Knowles
- Zilkha Neurogenetic Institute, and Department of Psychiatry, University of Southern California, Los Angeles, California 90033, USA
| | - Pat Levitt
- 1] Department of Pediatrics, Children's Hospital, Los Angeles, California 90027, USA [2] Keck School of Medicine, University of Southern California, Los Angeles, California 90089, USA
| | - John W Phillips
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Nenad Sestan
- Department of Neurobiology and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut 06510, USA
| | - Paul Wohnoutka
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Chinh Dang
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Amy Bernard
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - John G Hohmann
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
| | - Ed S Lein
- Allen Institute for Brain Science, Seattle, Washington 98103, USA
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48
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Nikkel SM, Major N, King WJ. Growth and development in thanatophoric dysplasia - an update 25 years later. Clin Case Rep 2013; 1:75-8. [PMID: 25356217 PMCID: PMC4184754 DOI: 10.1002/ccr3.29] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Revised: 10/14/2013] [Accepted: 10/18/2013] [Indexed: 11/08/2022] Open
Abstract
KEY CLINICAL MESSAGE Thanatophoric dysplasia is typically a neonatal lethal condition. However, for those rare individuals who do survive, there is the development of seizures, progression of craniocervical stenosis, ventilator dependence, and limitations in motor and cognitive abilities. Families must be made aware of these issues during the discussion of management plans.
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Affiliation(s)
- Sarah M Nikkel
- Department of Genetics Children's Hospital of Eastern Ontario Ottawa, Ontario, Canada ; Department of Pediatrics, University of Ottawa Ottawa, Ontario, Canada
| | - Nathalie Major
- Department of Pediatrics, University of Ottawa Ottawa, Ontario, Canada ; Department of Pediatrics, Children's Hospital of Eastern Ontario Ottawa, Ontario, Canada
| | - W James King
- Department of Pediatrics, University of Ottawa Ottawa, Ontario, Canada ; Department of Pediatrics, Children's Hospital of Eastern Ontario Ottawa, Ontario, Canada
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49
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Philpott CM, Widjaja E, Raybaud C, Branson HM, Kannu P, Blaser S. Temporal and occipital lobe features in children with hypochondroplasia/FGFR3 gene mutation. Pediatr Radiol 2013; 43:1190-5. [PMID: 23649205 DOI: 10.1007/s00247-013-2684-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 01/14/2013] [Accepted: 01/30/2013] [Indexed: 12/01/2022]
Abstract
BACKGROUND Thanatophoric dysplasia (TD) and hypochondroplasia are both caused by FGFR3 (fibroblast growth factor receptor 3) gene mutations. Temporal lobe dysplasia has been well described in thanatophoric dysplasia; however, only a couple of anecdotal cases of temporal lobe dysplasia in hypochondroplasia have been described. OBJECTIVE To define temporal lobe abnormalities in patients with hypochondroplasia, given that they share the same genetic mutation. MATERIALS AND METHODS We identified brain imaging studies of nine children with hypochondroplasia. The temporal lobes were assessed on CT and MRI for size and configuration of the temporal horn and aberrant sulcation of the inferior surface of the temporal lobe. RESULTS All children had a triangular-shape temporal horn and deep transverse fissures of the inferior temporal lobe surface. Neuroimaging in our cohort revealed enlarged temporal lobes and oversulcation of the mesial temporal and occipital lobes, with abnormal inferomedial orientation of these redundant gyri. Hippocampal dysplasia was also universal. CONCLUSION We confirmed frequent inferomesial temporal and occipital lobe abnormalities in our cohort of children with hypochondroplasia. Murine models with mutant fgfr3 display increased neuroprogenitor proliferation, cortical thickness and surface area in the temporo-occipital cortex. This is thought to result in excessive convolution and likely explains the imaging findings in this patient cohort. (Note that fgfr3 is the same genetic mutation in mice as FGFR3 is in humans.).
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Affiliation(s)
- Cristina M Philpott
- Department of Neuroradiology, The Hospital for Sick Children, Toronto, ON, Canada.
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50
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Abstract
The aim of our study was to retrospectively assess morphological findings in thanatophoric dysplasia, particularly, in how many cases were cerebral manifestations with temporal lobe dysplasia identified. We also wanted to register and analyze the proportions between lung, brain, and body weight. Criteria for inclusion were an autopsy performed during the period ranging from 1985 to 2009 with a diagnosis of thanatophoric dysplasia. During a 25-year period 25 cases of thanatophoric dysplasia were registered. Temporal lobe dysplasia was recognized in 52% of the cases, and after 1998 temporal lobe dysplasia was described in all cases. In 19 cases the brain/body weight ratio was increased, and in all cases the lung/body weight ratio was below the corresponding ratio calculated according to standard measurements. In all but one case the ratio of brain to lung weight was increased. This study focuses on morphological findings, stressing the importance of temporal lobe dysplasia in confirming a diagnosis of thanatophoric dysplasia. Lung/body, brain/body, and brain/lung weight ratios confirm macrocephaly and lung hypoplasia, which are constant findings in cases involving thanatophoric dysplasia. Femur and brain morphology inclusive histology remains the ultimate tool for confirmation of this lethal condition, although it has to be seen in a context inclusive of radiological examination.
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Affiliation(s)
- Christina Vogt
- Department of Pathology and Medical Genetics, St Olavs Hospital, Trondheim University Hospital, Trondheim, Norway.
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