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Novel phenotype and genotype spectrum of WDR62 in two patients with associated primary autosomal recessive microcephaly. Ir J Med Sci 2022; 191:2733-2741. [PMID: 35031939 DOI: 10.1007/s11845-021-02890-y] [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: 10/06/2021] [Accepted: 12/07/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND Microcephaly is a prominent feature of patients with primary autosomal recessive microcephaly 2 (MCPH2) caused by mutations in the WD Repeat Domain 62 (WDR62; OMIM: 613,583). AIM The study aimed to identify the underlying genetic factor(s) causing microcephaly in two patients in a consanguineous Iranian family. METHODS Two male patients (11 and 27 years old) were noticed due to microcephaly, neurodevelopmental delay, and occasional seizures. The younger patient (the proband) was subjected to paired-end whole-exome sequencing followed by Sanger sequencing to detect any underlying genetic factor. RESULTS Upon examination, both patients showed microcephaly as a prominent manifestation; they were under-weighted as well. The patients had a moderate gross motor impairment, severe cognitive disability and speech delay, increased deep tendon reflexes, flexible joint contractures, sensorineural hearing loss, and vertical nystagmus as a new ocular finding. The proband had more severe neurodevelopmental delay symptoms. The brain magnetic resonance imaging series revealed severe structural and cortical brain abnormalities in addition to hemiatrophy. Using Whole-exome Sequencing, a novel homozygous missense variant-NM_001083961.2; c.1598A > G: p.(His533Arg)-was identified in the WDR62. Subsequently, in silico analyses determined the possible impacts of the novel variant on the structure and function of WDR62 protein. CONCLUSIONS Herein, we identified a novel homozygous missense variant in the WDR62 in two patients with MCPH2. Vertical nystagmus and sensorineural hearing loss were detected as novel neurological findings. The present study expands the phenotype and genotype spectrum of MCPH2.
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Pałasz A, Della Vecchia A, Saganiak K, Worthington JJ. Neuropeptides of the human magnocellular hypothalamus. J Chem Neuroanat 2021; 117:102003. [PMID: 34280488 DOI: 10.1016/j.jchemneu.2021.102003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 01/30/2023]
Abstract
Hypothalamic magnocellular nuclei with their large secretory neurons are unique and phylogenetically conserved brain structures involved in the continual regulation of important homeostatic and autonomous functions in vertebrate species. Both canonical and newly identified neuropeptides have a broad spectrum of physiological activity at the hypothalamic neuronal circuit level located within the supraoptic (SON) and paraventricular (PVN) nuclei. Magnocellular neurons express a variety of receptors for neuropeptides and neurotransmitters and therefore receive numerous excitatory and inhibitory inputs from important subcortical neural areas such as limbic and brainstem populations. These unique cells are also densely innervated by axons from other hypothalamic nuclei. The vast majority of neurochemical maps pertain to animal models, mainly the rodent hypothalamus, however accumulating preliminary anatomical structural studies have revealed the presence and distribution of several neuropeptides in the human magnocellular nuclei. This review presents a novel and comprehensive evidence based evaluation of neuropeptide expression in the human SON and PVN. Collectively this review aims to cast a new, medically oriented light on hypothalamic neuroanatomy and contribute to a better understanding of the mechanisms responsible for neuropeptide-related physiology and the nature of possible neuroendocrinal interactions between local regulatory pathways.
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Affiliation(s)
- Artur Pałasz
- Department of Histology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, ul. Medyków 18, 40-752, Katowice, Poland.
| | - Alessandra Della Vecchia
- Department of Clinical and Experimental Medicine, Section of Psychiatry, University of Pisa, 67, Via Roma, 56100, Pisa, Italy
| | - Karolina Saganiak
- Department of Anatomy, Collegium Medicum, Jagiellonian University, ul. Kopernika 12, 31-034, Kraków, Poland
| | - John J Worthington
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
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Prevalence of congenital microcephaly and its risk factors in an area at risk of Zika outbreaks. BMC Pregnancy Childbirth 2021; 21:214. [PMID: 33731027 PMCID: PMC7972338 DOI: 10.1186/s12884-021-03705-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 03/10/2021] [Indexed: 11/17/2022] Open
Abstract
Background Prevalence of neonatal microcephaly in populations without Zika-epidemics is sparse. The study aimed to report baseline prevalence of congenital microcephaly and its relationship with prenatal factors in an area at risk of Zika outbreak. Methods This study included singletons born after 24 gestational weeks in 2017–2018 at four hospitals in Guangzhou, China. Microcephaly was defined as a head circumference at birth >3SD below the mean for sex and gestational age. Prevalence of microcephaly was estimated by binomial exact method. Multivariable logistic regression was used to examine the associations of microcephaly with prenatal factors. The population attributable fraction (PAF) for associated risk factors was calculated. Results Of 46,610 live births included, 154 (3.3, 95% CI 2.8–3.9 per 1000 live births) microcephalies were identified. Maternal hepatitis B virus carriers (HBV, OR 1.80, 95% CI 1.05–3.10) and primipara (OR 2.68, 95% CI 1.89–3.81) had higher risk of having a microcephalic baby. Higher prevalence of microcephaly was observed in women who had premature labor (OR 1.98, 95% CI 1.17–3.34) and had a baby with fetal growth restriction (OR 16.38, 95% CI 11.81–22.71). Four identified factors (HBV, primiparity, preterm labor, and fetal growth restriction) contributed to 66.4% of the risk of microcephaly. Conclusions The prevalence of microcephaly in Guangzhou was higher than expected. This study identified four prenatal risk factors that, together, contributed to two-thirds of the increased risk of microcephaly. This is the first reported association between maternal HBV carrier status and microcephaly.
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Banerjee S, Chen H, Huang H, Wu J, Yang Z, Deng W, Chen D, Deng J, Su Y, Li Y, Wu C, Wang Y, Zeng H, Wang Y, Li X. Novel mutations c.28G>T (p.Ala10Ser) and c.189G>T (p.Glu63Asp) in WDR62 associated with early onset acanthosis and hyperkeratosis in a patient with autosomal recessive microcephaly type 2. Oncotarget 2018; 7:78363-78371. [PMID: 27852057 PMCID: PMC5346645 DOI: 10.18632/oncotarget.13279] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Accepted: 11/01/2016] [Indexed: 11/28/2022] Open
Abstract
Microcephaly (MCPH) is a developmental disorder characterized by reduced brain size and intellectual disability. A proportion of microcephaly is caused by defects in a single gene. Microcephaly 2 (MCPH2) is one of the most frequent subtypes of MCPH.WD repeat-containing protein 62 gene (WDR62) is the most frequently mutated gene in MCPH2 patients. Phenotypes involving dermatological changes in MCPH2 have not been reported. We have identified and investigated a 5-year-old Chinese girl with markedly reduced brain size (86% of normal size), intellectual disability and psychomotor developmental delay. The patient also exhibited spattered blisters and reduced hair density on her head, anisochromasia with reticular hyperpigmentation and hypopigmentation on the trunk, which she has had since the age of 4 and had been found by her parents. Histological examination of a skin biopsy revealed acanthosis, hyperkeratosis and necrotic keratinocytes. Whole exome and Sanger sequencing identified two novel missense mutations, c.28G>T and c.189G>T, in the WDR62 gene. Both the mutations non-synonymously affect evolutionarily conserved amino acids and are predicted to be disease causing. We report the first case of MCPH2 that also presented with marked dermatological changes. Our findings expand the mutational and phenotypical spectra of MCPH2 and are valuable in the mutation-based pre- and post-natal screening and genetic diagnosis for MCPH2.
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Affiliation(s)
| | | | | | - Jing Wu
- BGI-Shenzhen, Shenzhen, China
| | - Zhiyun Yang
- Department of Medical Imaging, 1st affiliated hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Weiping Deng
- Department of Dermatology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, PR China
| | | | | | - Yan Su
- BGI-Shenzhen, Shenzhen, China
| | - Yang Li
- BGI-Shenzhen, Shenzhen, China
| | - Chao Wu
- Department of Neurology, 1st affiliated hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Ye Wang
- Department of Medical Genetics, Center for Genome Research, Sun Yat-sen University, Guangzhou, PR China
| | - Hao Zeng
- Department of Medical Genetics, Center for Genome Research, Sun Yat-sen University, Guangzhou, PR China
| | - Yiming Wang
- Xinhua College, Sun Yat-sen university, Guangzhou, PR China.,BGI-Shenzhen, Shenzhen, China
| | - Xunhua Li
- Department of Neurology, 1st affiliated hospital, Sun Yat-sen University, Guangzhou, PR China
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Orioli IM, Dolk H, Lopez-Camelo JS, Mattos D, Poletta FA, Dutra MG, Carvalho FM, Castilla EE. Prevalence and clinical profile of microcephaly in South America pre-Zika, 2005-14: prevalence and case-control study. BMJ 2017; 359:j5018. [PMID: 29162597 PMCID: PMC5696624 DOI: 10.1136/bmj.j5018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Objective To describe the prevalence and clinical spectrum of microcephaly in South America for the period 2005-14, before the start of the Zika epidemic in 2015, as a baseline for future surveillance as the Zika epidemic spreads and as other infectious causes may emerge in future.Design Prevalence and case-control study.Data sources ECLAMC (Latin American Collaborative Study of Congenital Malformations) database derived from 107 hospitals in 10 South American countries, 2005 to 2014. Data on microcephaly cases, four non-malformed controls per case, and all hospital births (all births for hospital based prevalence, resident within municipality for population based prevalence). For 2010-14, head circumference data were available and compared with Intergrowth charts.Results 552 microcephaly cases were registered, giving a hospital based prevalence of 4.4 (95% confidence interval 4.1 to 4.9) per 10 000 births and a population based prevalence of 3.0 (2.7 to 3.4) per 10 000. Prevalence varied significantly between countries and between regions and hospitals within countries. Thirty two per cent (n=175) of cases were prenatally diagnosed; 29% (n=159) were perinatal deaths. Twenty three per cent (n=128) were associated with a diagnosed genetic syndrome, 34% (n=189) polymalformed without a syndrome diagnosis, 12% (n=65) with associated neural malformations, and 26% (n=145) microcephaly only. In addition, 3.8% (n=21) had a STORCH (syphilis, toxoplasmosis, other including HIV, rubella, cytomegalovirus, and herpes simplex) infection diagnosis and 2.0% (n=11) had consanguineous parents. Head circumference measurements available for 184/235 cases in 2010-14 showed 45% (n=82) more than 3 SD below the mean, 24% (n=44) between 3 SD and 2 SD below the mean, and 32% (n=58) larger than -2 SD.Conclusion Extrapolated to the nearly 7 million annual births in South America, an estimated 2000-2500 microcephaly cases were diagnosed among births each year before the Zika epidemic began in 2015. Clinicians are using more than simple metrics to make microcephaly diagnoses. Endemic infections are important enduring causes of microcephaly.
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Affiliation(s)
- Iêda M Orioli
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Department of Genetics, Institute of Biology, Federal University of Rio de Janeiro, 21944-001, Rio de Janeiro, Brazil
- National Institute of Population Medical Genetics (INAGEMP), Porto Alegre, Brazil
| | - Helen Dolk
- Maternal Fetal and Infant Research Centre, Institute of Nursing and Health Research, Ulster University, Newtownabbey, Northern Ireland, UK
| | - Jorge S Lopez-Camelo
- National Institute of Population Medical Genetics (INAGEMP), Porto Alegre, Brazil
- ECLAMC at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
| | - Daniel Mattos
- Latin American Collaborative Study of Congenital Malformations (ECLAMC) at Department of Genetics, Institute of Biology, Federal University of Rio de Janeiro, 21944-001, Rio de Janeiro, Brazil
- National Institute of Population Medical Genetics (INAGEMP), Porto Alegre, Brazil
| | - Fernando A Poletta
- National Institute of Population Medical Genetics (INAGEMP), Porto Alegre, Brazil
- ECLAMC at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
| | - Maria G Dutra
- National Institute of Population Medical Genetics (INAGEMP), Porto Alegre, Brazil
- ECLAMC at Laboratory of Congenital Malformations Epidemiology, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| | - Flavia M Carvalho
- National Institute of Population Medical Genetics (INAGEMP), Porto Alegre, Brazil
- ECLAMC at Laboratory of Congenital Malformations Epidemiology, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| | - Eduardo E Castilla
- National Institute of Population Medical Genetics (INAGEMP), Porto Alegre, Brazil
- ECLAMC at Center for Medical Education and Clinical Research (CEMIC-CONICET), Buenos Aires, Argentina
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James HE, Perszyk AA, MacGregor TL, Aldana PR. The value of head circumference measurements after 36 months of age: a clinical report and review of practice patterns. J Neurosurg Pediatr 2015; 16:186-94. [PMID: 25932781 DOI: 10.3171/2014.12.peds14251] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The cranium is documented to grow from birth through adolescence. The standard of practice in primary care is measuring head circumference and plotting growth using curves that stop at 36 months. The authors report the importance of their experience with measuring head circumference in the child and same-sex parent beyond 36 months. METHODS In the University of Florida genetics and pediatric neurosurgery clinics, head circumference is measured and plotted on growth charts through 18 years of age. Circumference and rate of growth over time are compared with those of the same-sex parent. A diagnostic workup is initiated if there is a discrepancy with the patient's head circumference or if there is significant change in the growth rate of the cranium. RESULTS Between January 2004 and December 2007, the lead author examined 190 patients referred by pediatricians and/or pediatric subspecialists because of the concerns regarding head size of the child. Neuroimaging was performed in 70% of the patients prior to referral. None of the patients had their head size compared with that of their same-sex parent prior to referral. On assessing referring physician responses as to why the same-sex parents, head measurements were not pursued prior to imaging or referral to the specialists, the results were: 1) only have head circumference sheets to 36 months of age (n = 28); 2) the American Academy of Pediatrics does not recommend it (n = 3); and 3) the head stops growing at 36 months of age (n = 2). CONCLUSIONS Pediatricians and pediatric subspecialists need instruction on head circumference measurement in children from infancy through adolescence, and when indicated, in comparison with the head size of the same-sex parent. This measurement may be an effective and inexpensive assessment tool.
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Affiliation(s)
- Hector E James
- Division of Pediatric Neurosurgery, University of Florida College of Medicine Jacksonville, Lucy Gooding Pediatric Neurosurgery Center at Wolfson Children's Hospital, and Baptist Health of Northeast Florida; and
| | - Anthony A Perszyk
- Division of Clinical Genetics, University of Florida College of Medicine, Jacksonville, Florida
| | - Teresa L MacGregor
- Division of Pediatric Neurosurgery, University of Florida College of Medicine Jacksonville, Lucy Gooding Pediatric Neurosurgery Center at Wolfson Children's Hospital, and Baptist Health of Northeast Florida; and
| | - Philipp R Aldana
- Division of Pediatric Neurosurgery, University of Florida College of Medicine Jacksonville, Lucy Gooding Pediatric Neurosurgery Center at Wolfson Children's Hospital, and Baptist Health of Northeast Florida; and
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Baab KL, McNulty KP, Harvati K. Homo floresiensis contextualized: a geometric morphometric comparative analysis of fossil and pathological human samples. PLoS One 2013; 8:e69119. [PMID: 23874886 PMCID: PMC3707875 DOI: 10.1371/journal.pone.0069119] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 06/11/2013] [Indexed: 11/19/2022] Open
Abstract
The origin of hominins found on the remote Indonesian island of Flores remains highly contentious. These specimens may represent a new hominin species, Homo floresiensis, descended from a local population of Homo erectus or from an earlier (pre-H. erectus) migration of a small-bodied and small-brained hominin out of Africa. Alternatively, some workers suggest that some or all of the specimens recovered from Liang Bua are pathological members of a small-bodied modern human population. Pathological conditions proposed to explain their documented anatomical features include microcephaly, myxoedematous endemic hypothyroidism (“cretinism”) and Laron syndrome (primary growth hormone insensitivity). This study evaluates evolutionary and pathological hypotheses through comparative analysis of cranial morphology. Geometric morphometric analyses of landmark data show that the sole Flores cranium (LB1) is clearly distinct from healthy modern humans and from those exhibiting hypothyroidism and Laron syndrome. Modern human microcephalic specimens converge, to some extent, on crania of extinct species of Homo. However in the features that distinguish these two groups, LB1 consistently groups with fossil hominins and is most similar to H. erectus. Our study provides further support for recognizing the Flores hominins as a distinct species, H. floresiensis, whose affinities lie with archaic Homo.
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Affiliation(s)
- Karen L. Baab
- Department of Anthropology and Interdepartmental Doctoral Program in Anthropological Sciences, Stony Brook University, Stony Brook, New York, United States of America
- * E-mail:
| | - Kieran P. McNulty
- Evolutionary Anthropology Laboratory and Department of Anthropology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Katerina Harvati
- Department of Early Prehistory and Quaternary Ecology, Senckenberg Center for Human Evolution and Paleoecology, Eberhard Karls University of Tübingen, Tübingen, Germany
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Craniometric measures of microcephaly using MRI. Early Hum Dev 2012; 88:135-40. [PMID: 21820253 DOI: 10.1016/j.earlhumdev.2011.07.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Revised: 07/10/2011] [Accepted: 07/11/2011] [Indexed: 11/23/2022]
Abstract
BACKGROUND Microcephalic brains exhibit varying sizes, shapes, and dimensions when compared to normocephalic counterparts, but the extent of these differences is unresolved. AIMS To ascertain developmental changes in brain morphology using craniometric (linear brain) measures derived from MRI in microcephalic individuals and in normocephalic controls. STUDY DESIGN A retrospective, cross-sectional cohort study. SUBJECTS Twenty-one primary and secondary microcephalic individuals ages 2 postnatal weeks to 8.5 years with occipito-frontal circumference<2nd percentile for age; 83 age-equivalent normocephalic controls. OUTCOME MEASURES Age, sex, weight, height, body mass index, occipito-frontal circumference, and diagnosis prompting the MRI scan. Sixteen craniometric measures to determine specific ratios and age-related changes in brain shape and size. RESULTS Microcephalic infants and children not only have abnormally small brains but also proportionately lower weights and heights. The brain volumes of both primary and secondary microcephalics were quite variable, ranging from 266 to 723 cm(3) and 440 to 730 cm(3), respectively (p=0.34). Despite their smaller sizes, the shapes of 15/21 (71%) microcephalic brains were similar to those of age-equivalent controls. Cerebral hemispheric configurations were not consistent among the 6 misshapen brains, which included 2 primary, 3 secondary, and 1 unknown microcephalics. Older microcephalic brains could be distinguished from their normocephalic counterparts by two specific craniometric ratios (frontal cerebellar pole/sagittal cerebral length; axial temporal width/axial cerebellar width), each incorporating cerebral and cerebellar dimensions in either length or width. CONCLUSIONS The findings should provide useful information for distinguishing the characteristics of both modern and ancient microcephalic from normocephalic brains.
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(Re-)activation of neurons in aging and dementia: Lessons from the hypothalamus. Exp Gerontol 2011; 46:178-84. [DOI: 10.1016/j.exger.2010.08.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 08/25/2010] [Accepted: 08/27/2010] [Indexed: 01/22/2023]
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James HE, Perszyk A. Concepts on childhood microcrania: a clinical overview for the neurosurgeon who is evaluating a child with a small head. Pediatr Neurosurg 2011; 47:354-8. [PMID: 22584605 DOI: 10.1159/000337875] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 03/02/2012] [Indexed: 11/19/2022]
Abstract
PURPOSE Infants and children with microcrania are referred to pediatric neurosurgeons for evaluation and treatment of possible craniosynostosis and other disorders. We present an approach to these children to facilitate the appropriate clinical evaluation and management. METHODS We reviewed our experience and the literature on infants and children with microcephaly, and developed a management strategy for these children when seen in the University of Florida Division of Pediatric Neurosurgery. RESULTS We request the same sex parent to accompany the child for their consultation. If the head circumference of the child matches that of the same sex parent in percentiles, and there are no other abnormalities, no further assessment or studies are performed. If there is a disproportionate head size to that of the same sex parent and/or other structural abnormalities are present, the child is referred to clinical genetics for further assessment. CONCLUSIONS When patients are referred to pediatric neurosurgery for microcrania, their head size should be compared to that of the same sex parent. This will facilitate the diagnosis of familial microcephaly, and if no other abnormalities are noted, no further studies or surgical interventions are necessary.
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Affiliation(s)
- Hector E James
- University of Florida College of Medicine, Jacksonville, FL, USA. hector.james @ jax.ufl.edu
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Falk D, Hildebolt C, Smith K, Morwood M, Sutikna T, Jatmiko, Wayhu Saptomo E, Prior F. LB1’s virtual endocast, microcephaly, and hominin brain evolution. J Hum Evol 2009; 57:597-607. [DOI: 10.1016/j.jhevol.2008.10.008] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 09/23/2008] [Accepted: 10/30/2008] [Indexed: 11/29/2022]
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Falk D, Hildebolt C, Smith K, Jungers W, Larson S, Morwood M, Sutikna T, Jatmiko, Saptomo EW, Prior F. The type specimen (LB1) ofHomo floresiensisdid not have Laron Syndrome. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2009; 140:52-63. [DOI: 10.1002/ajpa.21035] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
Because the cranial capacity of LB1 (Homo floresiensis) is only 417 cm(3), some workers propose that it represents a microcephalic Homo sapiens rather than a new species. This hypothesis is difficult to assess, however, without a clear understanding of how brain shape of microcephalics compares with that of normal humans. We compare three-dimensional computed tomographic reconstructions of the internal braincases (virtual endocasts that reproduce details of external brain morphology, including cranial capacities and shape) from a sample of 9 microcephalic humans and 10 normal humans. Discriminant and canonical analyses are used to identify two variables that classify normal and microcephalic humans with 100% success. The classification functions classify the virtual endocast from LB1 with normal humans rather than microcephalics. On the other hand, our classification functions classify a pathological H. sapiens specimen that, like LB1, represents an approximately 3-foot-tall adult female and an adult Basuto microcephalic woman that is alleged to have an endocast similar to LB1's with the microcephalic humans. Although microcephaly is genetically and clinically variable, virtual endocasts from our highly heterogeneous sample share similarities in protruding and proportionately large cerebella and relatively narrow, flattened orbital surfaces compared with normal humans. These findings have relevance for hypotheses regarding the genetic substrates of hominin brain evolution and may have medical diagnostic value. Despite LB1's having brain shape features that sort it with normal humans rather than microcephalics, other shape features and its small brain size are consistent with its assignment to a separate species.
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Falk D, Hildebolt C, Smith K, Morwood MJ, Sutikna T, Jatmiko, Saptomo EW, Brunsden B, Prior F. Response to Comment on "The Brain of LB1,
Homo floresiensis
". Science 2006. [DOI: 10.1126/science.1124972] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Dean Falk
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - Charles Hildebolt
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - Kirk Smith
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - M. J. Morwood
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - Thomas Sutikna
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - Jatmiko
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - E. Wayhu Saptomo
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - Barry Brunsden
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
| | - Fred Prior
- Department of Anthropology, Florida State University, Tallahassee, FL 32306, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Archaeology and Palaeoanthropology, University of New England, Armidale, New South Wales 2351, Australia
- Indonesian Centre for Archaeology, JI. Raya Condet Pejaten No. 4, Jakarta 12001, Indonesia
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15
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Martin RD, Maclarnon AM, Phillips JL, Dobyns WB. Flores hominid: New species or microcephalic dwarf? ACTA ACUST UNITED AC 2006; 288:1123-45. [PMID: 17031806 DOI: 10.1002/ar.a.20389] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The proposed new hominid "Homo floresiensis" is based on specimens from cave deposits on the Indonesian island Flores. The primary evidence, dated at approximately 18,000 y, is a skull and partial skeleton of a very small but dentally adult individual (LB1). Incomplete specimens are attributed to eight additional individuals. Stone tools at the site are also attributed to H. floresiensis. The discoverers interpreted H. floresiensis as an insular dwarf derived from Homo erectus, but others see LB1 as a small-bodied microcephalic Homo sapiens. Study of virtual endocasts, including LB1 and a European microcephalic, purportedly excluded microcephaly, but reconsideration reveals several problems. The cranial capacity of LB1 ( approximately 400 cc) is smaller than in any other known hominid < 3.5 Ma and is far too small to derive from Homo erectus by normal dwarfing. By contrast, some associated tools were generated with a prepared-core technique previously unknown for H. erectus, including bladelets otherwise associated exclusively with H. sapiens. The single European microcephalic skull used in comparing virtual endocasts was particularly unsuitable. The specimen was a cast, not the original skull (traced to Stuttgart), from a 10-year-old child with massive pathology. Moreover, the calotte does not fit well with the rest of the cast, probably being a later addition of unknown history. Consideration of various forms of human microcephaly and of two adult specimens indicates that LB1 could well be a microcephalic Homo sapiens. This is the most likely explanation for the incongruous association of a small-brained recent hominid with advanced stone tools.
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Affiliation(s)
- Robert D Martin
- Academic Affairs, Field Museum, Chicago, Illinois 60605, USA.
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16
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Weber J, Czarnetzki A, Pusch CM. Response to Comment on "The Brain of LB1,
Homo floresiensis
". Science 2005; 310:236; author reply 236. [PMID: 16224005 DOI: 10.1126/science.1117062] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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17
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Affiliation(s)
- Jochen Weber
- Department of Neurosurgery Leopoldina Hospital 97422 Schweinfurt, Germany
| | - Alfred Czarnetzki
- Department of Paleoanthropology and Osteology University of Tübingen 72074 Tübingen, Germany
| | - Carsten M. Pusch
- Institute of Anthropology and Human Genetics University of Tübingen 72074 Tübingen, Germany
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18
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Swaab DF, Dubelaar EJG, Hofman MA, Scherder EJA, van Someren EJW, Verwer RWH. Brain aging and Alzheimer's disease; use it or lose it. PROGRESS IN BRAIN RESEARCH 2002; 138:343-73. [PMID: 12432778 DOI: 10.1016/s0079-6123(02)38086-5] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
(1) Alzheimer's disease is a multifactorial disease in which age and APOE-epsilon 4 are important risk factors. (2) The neuropathological hallmarks of AD, i.e. amorphous plaques, neuritic plaques (NPs), pretangles, neurofibrillary tangles (NFT) and cell death are not part of a single pathogenetic cascade but may occur independently. (3) In brain areas where classical AD changes, i.e. NPs and NFTs, are present, such as the CA1 area of the hippocampus, the nucleus basalis of Meynert and the tuberomamillary nucleus, a decreased metabolic rate is found. The decreased metabolic rate appears not to be induced by the presence of pretangles, NFT or NPs. (4) Decreased metabolic rate may precede cognitive impairment and is thus an early occurring hallmark of AD, which, in principle, may be reversible. The observation that the administration of glucose or insulin enhances memory in AD patients also supports the view that AD has a metabolic basis. (5) Moreover, several observations in postmortem brain indicate that activated neurons are better able to withstand aging and AD, a phenomenon paraphrased by us as 'use it or lose it'. (6) It is, therefore, attractive to direct the development of therapeutic strategies towards restimulation of neuronal metabolic rate in order to improve cognition and other symptoms in AD. A number of pharmacological and non-pharmacological studies support the concept that activation of the brain has beneficial effects and may, to a certain degree, restore several aspects of cognition and other central functions. For instance, the circadian system may be restimulated in AD patients by exposing them to more light or transcutaneous nerve stimulation. A procedure has been developed to culture human postmortem brain tissue that allows testing of the efficacy of putative stimulatory compounds such as neurotrophins.
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Affiliation(s)
- D F Swaab
- Netherlands Institute for Brain Research, Meibergdreef 33, 1105 AZ Amsterdam, The Netherlands.
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19
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Lee MH, Rabe A. Premature decline in Morris water maze performance of aging micrencephalic rats. Neurotoxicol Teratol 1992; 14:383-92. [PMID: 1488032 DOI: 10.1016/0892-0362(92)90048-f] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The rat with methylazoxymethanol-induced micrencephaly is a useful animal model of congenital brain defects and associated cognitive impairment. Born with profound morphological and neurochemical alterations in the forebrain, it shows impaired ability to learn mazes. In order to determine how an animal with such a developmentally damaged brain would function in old age, Long-Evans rats 6, 15, and 24 months of age were tested for their ability to learn to locate a hidden platform in the Morris water maze. The performance of micrencephalic rats of all ages was impaired on acquisition, retention, and transfer trials. Moreover, the magnitude of their acquisition deficit increased with age. It remains to be determined whether the premature decline of the micrencephalic rat in learning the task simply reflects a greater impact on an already compromised brain by neuron loss characteristic of aging brains or whether the prenatal insult alters some basic processes resulting in premature aging.
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Affiliation(s)
- M H Lee
- New York State Institute for Basic Research in Developmental Disabilities, Staten Island 10314
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20
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Richards GD, Anton SC. Craniofacial configuration and postcranial development of a hydrocephalic child (ca. 2500 B.C.-500 A.D.): with a review of cases and comment on diagnostic criteria. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 1991; 85:185-200. [PMID: 1882981 DOI: 10.1002/ajpa.1330850207] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Hydrocephalus is a severe disorder of the central nervous system characterized by absorption blockage of the cerebral spinal fluid (CSF). The archaeological record of the condition ranges in time from 10,000 B.C. to 1670 A.D. and consists of 30 possible cases worldwide. A review of this material reveals that diagnostic criteria which fully delineate the condition have not been established. Previously, no attempt has been made to differentiate the two major categories of hydrocephalus and their subgroupings, or to identify other conditions which might result in similar morphologies. A partial child's skeleton from the Middle Period (ca. 2500 B.C. to 500 A.D.) of Central California Prehistory is described in light of an extensive clinical literature. Examination of this individual reveals a unique craniofacial configuration and malformed postcrania. Bony criteria for a differential diagnosis of hydrocephalus are established and applied to this individual. Based on these criteria, the individual is diagnosed as having a chronic form of noncommunicating hydrocephalus. Blockage of the CSF pathway most likely occurred in the aqueduct of Sylvius with a partial occlusion of the foramen of Monro or a frontal cyst. In addition, femoral development is suggestive of partial paralysis.
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Affiliation(s)
- G D Richards
- Department of Anthropology, University of California, Berkeley 94720
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21
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Abstract
Rett syndrome is an increasingly recognized progressive disorder in females, commencing in infancy and characterized by autistic behavior, gait ataxia, stereotyped movements, seizures and generalized growth and mental retardation, possibly associated with disorders of central biogenic amine synthesis. The gene locus and pathogenesis of Rett syndrome are unknown. Autopsy studies in nine girls dying between 4 and 17 years, and sural nerve and muscle biopsies from two girls aged 3 and 17 years showed: (1) diffuse cortical atrophy/micrencephaly, with a decrease in brain weight by 12% to 34% of age-matched controls, apparently related to the duration of the disorder; (2) mild diffuse cortical atrophy with increased amounts of neuronal lipofuscin and occasional mild gliosis, but without signs of a storage disorder; (3) underpigmentation of the zona compacta nigrae, which showed fewer well-pigmented neurons for age and fewer melanin granules per neuron, while total numbers of nigral neurons and the substructure of neuromelanin were normal for age. No pathological changes were seen in other transmitter-specific brain stem nuclei; (4) immunoreactivity for tyrosine hydroxylase was slightly reduced in nigral and hypothalamic neurons, and the pituitary gland showed decreased immunoreaction for prolactin and growth hormone; (5) ultrastructurally, in frontal cortex and caudate nucleus, isolated abnormal neurites and reactive or degenerative axonal swellings were seen; the latter are possibly related to the nigral changes, suggesting some dysfunction of the dopaminergic nigrostriatal system, which is supported by neurochemical data; (6) preliminary biochemical studies revealed increased beta-endorphines in thalamus and cerebellum; (7) peripheral nerves demonstrated increase in small fibers without demyelination and increased numbers of neurofilaments in axons, suggesting distal axonopathy, while skeletal muscle showed alterations in the sarcoplasmic reticulum with circular profiles in the Z-filaments. These nonspecific changes may be interpreted as early signs of denervation. The variety of lesions in the central, neuroendocrine and peripheral neuromuscular systems in Rett syndrome are discussed with regard to their clinical and biochemical significance.
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Affiliation(s)
- K Jellinger
- Ludwig Boltzmann Institut für klinische Neurobiologie, Lainz-Hospital, Wien, Austria
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22
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Jellinger K, Seitelberger F. Neuropathology of Rett syndrome. AMERICAN JOURNAL OF MEDICAL GENETICS. SUPPLEMENT 1986; 1:259-88. [PMID: 3087188 DOI: 10.1002/ajmg.1320250528] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Autopsy studies in 8 girls with the Rett syndrome dying between 4 and 15 years showed: Diffuse cerebral atrophy/micrencephaly, with a decrease in brain weight by 13.8 to 33.8% of age-matched controls, apparently related to the duration of the disorder; Mild, but inconsistent diffuse cortical atrophy without developmental disorders apart from occasional microdysgenesis (three cases), but increased amounts of neuronal lipofuscin, and occasional mild astrocytic gliosis; Mild, but inconsistent spongy changes in cerebral and cerebellar white matter, optic nerve (two cases), and myelinated fascicles of the brainstem tegmentum, without signs of dys- or demyelination, and apparently different from the spongy myelinopathy common to aminoacidopathies; Most conspicuous was an underpigmentation of the substantia nigra which contained many fewer well-pigmented neurons for age (53-73%), and fewer pigmented granules per neuron, while the total number of nigral neurons and the triphasic substructure of neuromelanin were normal for age. No pathologic changes were seen in locus coeruleus, nucleus basalis of Meynert, and nucleus dorsalis raphe; Electron microscopy of autopsy material from an 11-year-old girl showed increased amounts of neuronal lipofuscin without signs of a storage disorder. Reactive and degenerating axons in the caudate nucleus were possibly related to the nigral changes, suggesting some dysfunction of the dopaminergic nigro-striatal system, while the synaptic organization of the neostriatum appeared unaffected. Peripheral nerve from a patient dying in advanced stage showed increased numbers of unmyelinated (regenerated?) axons, with almost no demyelination and few remyelinated axons, suggesting axonal degeneration rather than hypomyelination, but exogenous factors (malnutrition) cannot be excluded. The pathogenetic mechanisms of the morphologic brain lesions and their relations to clinical and neurochemical findings in Rett syndrome are unknown and deserve further intensive investigations.
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