Hostname: page-component-848d4c4894-v5vhk Total loading time: 0 Render date: 2024-06-19T19:14:08.922Z Has data issue: false hasContentIssue false
  • English
  • Français

Rett Syndrome: Investigation of Nine Patients, including PET Scan

Published online by Cambridge University Press:  02 December 2014

Henry G. Dunn ,
A. Jon Stoessl ,
Helena H. Ho ,
Patrick M. MacLeod ,
Kenneth J. Poskitt ,
Doris J. Doudet ,
Michael Schulzer ,
Derek Blackstock ,
Teresa Dobko  and
Ben Koop
...Show all authors
Henry G. Dunn
Affiliation:
From the Division of Neurology, Department of Pediatrics University of Victoria, Victoria, BC Canada.
A. Jon Stoessl
Affiliation:
Department of Medicine/Neurology University of Victoria, Victoria, BC Canada.
Helena H. Ho
Affiliation:
From the Division of Neurology, Department of Pediatrics University of Victoria, Victoria, BC Canada.
Patrick M. MacLeod
Affiliation:
University of British Columbia, Vancouver, BC; Section of Genetics, Department of Laboratory Medicine, Capital Health Region, Victoria, BC University of Victoria, Victoria, BC Canada.
Kenneth J. Poskitt
Affiliation:
Department of Radiology, BC’s Children’s Hospital, Vancouver, BC University of Victoria, Victoria, BC Canada.
Doris J. Doudet
Affiliation:
Department of Medicine/Neurology University of Victoria, Victoria, BC Canada.
Michael Schulzer
Affiliation:
Medicine and Statistics University of Victoria, Victoria, BC Canada.
Derek Blackstock
Affiliation:
Department of Anesthesiology University of Victoria, Victoria, BC Canada.
Teresa Dobko
Affiliation:
UBCTRIUMF PET Program University of Victoria, Victoria, BC Canada.
Ben Koop
Affiliation:
University of British Columbia, Vancouver, BC; Department of Biology University of Victoria, Victoria, BC Canada.
Giovana V. de Amorim
Affiliation:
University of British Columbia, Vancouver, BC; Department of Biology University of Victoria, Victoria, BC Canada.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.
Background:

We describe nine females with Rett Syndrome (RS), aged 14 to 26 years. All had had developmental delay before the end of their first year and had subsequently regressed to profound dementia with apraxia, ataxia, irregular respirations and often also seizures.

Methods:

The Revised Gesell developmental assessment and Alpern-Boll Developmental Profile were used in modified form. Volumetric measurements of basal ganglia using MRI were compared with the findings in nine age-matched volunteer females. Positron emission scans with [18F]-6-fluorodopa and [11C]-raclopride were performed under light anesthesia with intravenous Propofol, and the findings were compared with those in healthy control girls. Bidirectional sequencing of the coding regions of the MECP2 gene was investigated in blood samples for mutational analyses.

Results:

The RS females functioned at a mental age level ranging from about 4 to 15 months. The scores correlated with height, weight and head circumference. Magnetic resonance scans of basal ganglia showed a significant reduction in the size of the caudate heads and thalami in the Rett cases. Positron emission scans demonstrated that the mean uptake of fluorodopa in RS was reduced by 13.1% in caudate and by 12.5% in putamen as compared to the controls, while dopamine D2 receptor binding was increased significantly by 9.7% in caudate and 9.6% in putamen. Mutations in the coding regions of the MECP2 gene were present in all nine patients. No significant correlation between type and location of mutation and volumetric changes or isotope uptake was demonstrable.

Conclusion:

Our findings suggest a mild presynaptic deficit of nigrostriatal activity in Rett syndrome.

Résumé:

RÉSUMÉ:Introduction:

Nous décrivons les cas de neuf femmes, âgées de 14 à 26 ans, atteintes du syndrome de Rett (SR). Un retard de développement avait été observé chez toutes avant la fin de leur première année de vie. Toutes avaient régressé par la suite et présentaient une démence profonde avec apraxie, ataxie, respiration irrégulière et, dans plusieurs cas, des crises convulsives.

Méthodes:

Des versions modifiées de l’échelle révisée du développement de Gesell et du profil du développement d’Alpern-Boll ont été utilisées. Des mesures volumétriques des noyaux gris centraux par résonance magnétique ont été comparées à celles faites chez neuf femmes volontaires, appariées pour l’âge. La tomographie par émission de positons (PET scan) au [18F]-6-fluorodopa et au [11C]-raclopride a été effectuée sous anesthésie légère par le Propofol intraveineux et les observations ont été comparées à celles de femmes témoins normales. On a procédé à une analyse mutationnelle par séquençage bidirectionnel des régions codantes du gène MECP2.

Résultats:

Les femmes atteintes du SR fonctionnaient à un niveau d’âge mental de 4 à 15 mois. Les scores étaient corrélés à la taille, au poids et à la circonférence de la tête. La resonance magnétique des noyaux gris centraux a montré une réduction significative de la taille de la tête du noyau caudé et du thalamus chez les cas de SR. Le PET scan a montré que la captation moyenne de fluorodopa dans le SR était réduite de 13,1% dans le noyau caudé et de 12,4% dans le putamen par rapport aux contrôles et que la liaison aux récepteurs dopaminergiques D2 était augmentée significativement de 9,7% dans le noyau caudé et de 9,6% dans le putamen. Des mutations dans les régions codantes du gène MECP2 étaient présentes chez les neuf patientes. Aucune corrélation significative entre le type et le site des mutation et les changements volumétriques ou la captation isotopique n’a pu être démontrée.

Conclusion:

Nos observations suggèrent qu’il existe un léger déficit présynaptique de l’activité nigro-striée dans le SR.

Type
Research Article
Information
Canadian Journal of Neurological Sciences , Volume 29 , Issue 4 , November 2002 , pp. 345 - 357
Copyright
Copyright © The Canadian Journal of Neurological 2002

References

1. Chiron, C, Bultreau, C, Loch, C, et al. Dopaminergic D2 receptor SPECT imaging in Rett syndrome: increase of specific binding in striatum. J Nucl Med 1993;34:1717–1721.Google ScholarPubMed
2. Wenk, GL. Alterations in dopaminergic function in Rett syndrome. Neuropediatrics 1995;26:123–125.CrossRefGoogle ScholarPubMed
3. Webb, T, Clarke, A, Hanefeld, F, et al. Linkage analysis in Rett syndrome families suggests that there may be a critical region at Xq28. J Med Genet 1998;35:997–1003.CrossRefGoogle ScholarPubMed
4. Duvoisin, RC. Modified Columbia Scale. The evaluation of extrapyramidal disease. Symposium Bel-Air. In: de Ajuriaguerra, J, Gauthier, G, eds. Monoamines noyaux gris centraux et syndrome de Parkinson. Geneva: Georg et Cie. 1971:313–325.Google Scholar
5. Leenders, KL, Palmer, AJ, Quinn, N, et al. Brain dopamine metabolism in patients with Parkinson’s disease measured with positron emission tomography. J Neurol Neurosurg Psychiatry 1986;49:853–860.CrossRefGoogle ScholarPubMed
6. Julu, POO. The central autonomic disturbance in Rett syndrome. In: Kerr, A, Witt-Engerström I (Eds.) Rett Disorder and the Developing Brain. Oxford Univ Press:2001:131–181.CrossRefGoogle Scholar
7. Elian, M, Rudolf, ND. Observations on hand movements in Rett syndrome - a pilot study. Acta Neurol Scand 1996;94:212–214.CrossRefGoogle ScholarPubMed
8. Marcus, CL, Carroll, JL, McColley, SA, et al. Polysomnographic characteristics of patients with Rett syndrome. J Pediatr 1994;125:218–224.CrossRefGoogle ScholarPubMed
9. Chae, JH, Hwang, YS, Kim, KJ. Mutation analysis of MECP2 and clinical characterization in Korean patients with Rett syndrome. J Child Neurol 2002;17:33–36.CrossRefGoogle ScholarPubMed
10. Xiang, F, Stenbom, Y, Anvret, M, Hagberg, B. Closely related Swedish Rett syndrome females - none with MECP2 mutation revealed. Neuropediatrics 2001;32:217–218.CrossRefGoogle ScholarPubMed
11. Schwartzman, JS, Bernardino, A, Nishimura, A, Gomes, RR, Zatz, M. Rett syndrome in a boy with a 47,XXY karyotype confirmed by a rare mutation in the MECP2 gene. Neuropediatrics 2001;32:162–164.CrossRefGoogle Scholar
12. Nan, X, Campoy, FJ, Bird, A. MeCP2 is a transcriptional repressor with abundant binding sites in genomic chromatin. Cell 1997;88:471–481.CrossRefGoogle ScholarPubMed
13. Huppke, P, Laccone, F, Krämer, N, Engel, W, Hanefeld, F. Rett syndrome: analysis of MeCP2 and clinical characterization of 31 patients. Hum Molec Genet 2000;9:1369–1375.CrossRefGoogle ScholarPubMed
14. Saint-Hilaire, M-H, Burke, RE, Bressman, SB, Brin, MF, Fahn, S. Delayed onset dystonia due to perinatal or early childhood asphyxia. Neurology 1991; 41:216–222.CrossRefGoogle ScholarPubMed
15. Brooks, DJ, Ibanez, V, Sawle, GV, et al. Striatal D2 receptor status in patients with Parkinson’s disease, striatonigral degeneration and progressive supranuclear palsy, measured with C-raclopride and positron emission tomography. Ann Neurol 1992;32:184–192.CrossRefGoogle Scholar
16. Shyr, M-H, Tsai, TH, Yang, C-H, et al. Propofol anesthesia increases dopamine and serotonin activities at the somatosensory cortex in rats: a microdialysis study. Anesth Analg 1997;84:1344–1348.CrossRefGoogle ScholarPubMed
17. Leenders, KL, Antonini, A, Hess, K. Brain dopamine D2 receptor density in Parkinson’s disease measured with PET using [C]-raclopride. J Cereb Blood Flow Metab 1991;11 Suppl 2:818.Google Scholar
18. Laihinen, A, Rinne, JO, Någren, K, et al. Positron emission tomography of brain dopamine D2 receptors with C-raclopride in early Parkinson’s disease. Acta Radiol 1991; suppl 376:151.Google Scholar
19. Francke, U. Spectrum of MECP2 mutations in Rett syndrome. World Congress on Rett syndrome 2000. Symposium I:9.Google Scholar
20. Amano, K, Nomura, Y, Segawa, M, Yamakawa, K. Mutational analysis of the MECP2 gene in Japanese patients with Rett syndrome. J Hum Genet 2000;45:231–236.CrossRefGoogle ScholarPubMed
21. Hoffbuhr, K, Devaney, JM, La Fleur, B, et al. MeCP2 mutations in children with and without the phenotype of Rett syndrome. Neurology 2001;56:1486–1495.CrossRefGoogle ScholarPubMed
22. Laccone, F, Huppke, P, Hanefeld, F, Meins, M. Mutation spectrum in patients with Rett syndrome in the German population: evidence of hot spot regions. Hum Mutat 2001;17:183–190.CrossRefGoogle ScholarPubMed
23. Fulton, B, Sorkin, EM. Propofol, an overview of its pharmacology. Drugs 1995;50:636–657.CrossRefGoogle ScholarPubMed
24. Burke, RE, Fahn, S, Marsden, CD, et al. Validity and reliability of a rating scale for the primary torsion dystonias. Neurology 1985;35:73–77.CrossRefGoogle ScholarPubMed
25. Rousset, OG, Deep, P, Kuwabara, H, et al. Effect of partial volume correction on estimates of the influx and cerebral metabolism of 6-[F] fluoro-L-dopa studied with PET in normal control and Parkinson’s disease subjects. Synapse 2000;37:81–89.3.0.CO;2-#>CrossRefGoogle ScholarPubMed
26. Leonard, H, Thomson, MR, Glasson, EJ, et al. A population-based approach to the investigation of osteopenia in Rett syndrome. Dev Med Child Neurol 1999;41:323–328.Google Scholar
27. Shahbazian, MD, Antalffy, B, Armstrong, DL, Zoghbi, HY. Insight into Rett syndrome: MeCP2 levels display tissue- and cell-specific differences and correlate with neuronal maturation. Hum Mol Genet 2002;11:115–124.CrossRefGoogle ScholarPubMed
28. Rett, A. Über ein eigenartiges hirnatrophisches Syndrom bei Hyperammonämie im Kindesalter. Wien Med Wochenschr 1966;116:723–726 Google Scholar
29. Huppke, P, Held, M, Hanefeld, F, Engle, W, Laccone, F. Influence of mutation type and location on phenotype in 123 patients with Rett syndrome. Neuropediatrics 2002;33:63–68.CrossRefGoogle ScholarPubMed
30. Dunn, HG, MacLeod, PM. Rett syndrome: review of biological abnormalities. Can J Neurol Sci 2001;28:16–29.CrossRefGoogle ScholarPubMed
31. Giunti, L, Pelagatti, V, Lazzerini, S, et al. Spectrum and distribution of MECP2 mutations in 64 Italian Rett syndrome girls: tentative genotype/phenotype correlation. Brain Dev 2001;23 (Suppl 1):S242–S245.CrossRefGoogle ScholarPubMed
32. Antonini, A, Vontobel, P, Psylla, M, et al. Complementary positron emission tomographic studies of the striatal dopaminergic system in Parkinson’s disease. Arch Neurol 1995;52:1183–1190.CrossRefGoogle ScholarPubMed
33. Bhatt, MH, Obeso, JA, Marsden, CD. Time course of post-anoxic akinetic-rigid and dystonic syndromes. Neurology 1993;43:314–317.CrossRefGoogle Scholar
34. Cordes, M, Snow, BJ, Cooper, S, et al. Age-dependent decline of nigrostriatal dopaminergic function: a positron emission tomographic study of grandparents and their grandchildren. Ann Neurol 1994;36:667–670.CrossRefGoogle ScholarPubMed
35. Eidelberg, D, Takikawa, S, Dhawan, V, et al. Striatal F-dopa uptake: absence of an aging effect. J Cereb Blood Flow Metab 1993;13: 881–888.CrossRefGoogle Scholar
36. Appadu, BL, Strange, PG, Lambert, DG. Does Propofol interact with D2 dopamine receptors? Anesth Analg 1994;79:1191–1192.CrossRefGoogle ScholarPubMed
37. Kitt, CA, Wilcox, BJ. Preliminary evidence for neurodegenerative changes in the substantia nigra of Rett syndrome. Neuropediatrics 1995;26:114–118.CrossRefGoogle ScholarPubMed
38. Vingerhoets, FJG, Snow, BJ, Schulzer, MJ, et al. Reproducibility of fluorine-18-6-fluorodopa positron emission tomography in normal human subjects. J Nucl Med 1994;35:18–24.Google ScholarPubMed
39. Alpern, G, Boll, T, Shearer, M. Developmental Profile II Manual. Los Angeles: Western Psychological Services, 1992:Sixth Edition.Google Scholar
40. Bauman, ML, Kemper, TL, Arin, DM. Microscopic observations of the brain in Rett syndrome. Neuropediatrics 1995;26:105–108.CrossRefGoogle ScholarPubMed
41. Haas, RH, Dixon, SD, Sartoris, DJ, Hennessy, MJ. Osteopenia in Rett syndrome. J Pediatr 1997;131:771–774.CrossRefGoogle ScholarPubMed
42. Wenk, GL. Rett syndrome: evidence for normal dopaminergic function. Neuropediatrics 1996;27:256–259.CrossRefGoogle ScholarPubMed
43. Naidu, S, Kaufmann, W, Abrams, M, et al. Neuroimaging studies in Rett syndrome. World Congress on Rett Syndrome 2000. Plenary Lecture IV:6.Google Scholar
44. Schanen, C, Francke, U. A severely affected male born into a Rett syndrome kindred supports X-linked inheritance and allows extension of the exclusion map. Am J Hum Genet 1998;63:267–269.CrossRefGoogle ScholarPubMed
45. Amir, RE, Van den Veyver, IB, Wan, M, et al. Rett syndrome is caused by mutations in X-linked MECP2, encoding methyl-CpG-binding protein 2. Nat Genet 1999;23:185–188.CrossRefGoogle ScholarPubMed
46. Wan, M, Lee, SSJ, Zhang, X, et al. Rett syndrome and beyond: recurrent spontaneous and familial MECP2 mutations at CPG hotspots. Am J Hum Genet 1999;65:1520–1529.CrossRefGoogle ScholarPubMed
47. Van den Veyver, IB, Zoghbi, HY. Methyl-CpG binding protein 2 mutations in Rett syndrome. Curr Opin Genet Dev 2000;10:275–279.CrossRefGoogle ScholarPubMed
48. Hampson, K, Woods, CG, Latif, F, et al. Mutations in the MECP2 gene in a cohort of girls with Rett syndrome. J Med Genet 2000;37:610–612.CrossRefGoogle Scholar
49. Eidelberg, D, Moeller, JR, Dhawan, V, et al. The metabolic anatomy of Parkinson’s disease complementary [F] fluorodeoxyglucose and [F] fluorodopa positron emission tomography studies. Mov Disord 1990;5:203–213.CrossRefGoogle Scholar
50. Segawa, M. Neurons and neuronal systems involved in pathophysiology of Rett syndrome - from the standpoint of clinical neurology. World Congress on Rett Syndrome 2000, Nagano, Japan, Round Table Discussion :17.Google Scholar
51. Hagberg, B, Aicardi, J, Dias, K, Ramos, O. A progressive syndrome of autism, dementia, ataxia, and loss of purposeful hand use in girls: Rett’s syndrome: report of 35 cases. Ann Neurol 1983;14:471–479.CrossRefGoogle ScholarPubMed
52. Hagberg, B, Witt-Engerström, I. Rett syndrome: a suggested staging system for describing impairment profile with increasing age towards adolescence. Am J Med Genet 1986;24(Suppl 1):47–59.CrossRefGoogle Scholar
53. Bray, RJ. Propofol infusion syndrome in children. Paediatr Anaesth 1998;8:491–499.CrossRefGoogle ScholarPubMed
54. Borgeat, A, Ruetsch, YA. Spontaneous movement, Propofol and dopamine receptors. (Letter) Anaesthesia 1997;52:808–809.Google ScholarPubMed
55. Monrós, E, Armstrong, J, Aibar, E, et al. Rett syndrome in Spain: mutation analysis and clinical correlations. Brain Dev 2001;23 (Suppl 1):S251–S253.CrossRefGoogle ScholarPubMed
56. Huppke, P, Bohlander, S, Krämer, N, Laccone, F, Hanefeld, F. Altered methylation pattern of the G6PD promoter in Rett syndrome. Neuropediatrics 2002;33:105–108.CrossRefGoogle Scholar
57. Kaasinen, V, Ruottinen, HM, Nagren, K, et al. Upregulation of putaminal dopamine D2 receptors in early Parkinson’s disease: a comparative PET study with [C]-raclopride and [C]N-methylspiperone. J Nucl Med 2000;41:65–70.Google ScholarPubMed
58. Couvert, P, Bienvenu, T, Aquaviva, C, et al. MECP2 is highly mutated in X-linked mental retardation. Hum Mol Genet 2001;10:941–946.CrossRefGoogle ScholarPubMed
59. Hagberg, G, Stenbom, Y, Witt-Engerström I. Head growth in Rett syndrome. Acta Paediatrica 2000;89:198–202.CrossRefGoogle ScholarPubMed
60. Hansman, C. Anthropometry and Related Data. In: McCammon, RW (Ed.) Human Growth and Development. Springfield, IL: C.C. Thomas, 1970:101–154.Google Scholar
61. Knobloch, H, Stevens, F, Malone, AF. Manual of Developmental Diagnosis: The Administration and Interpretation of the Revised Gesell and Amatruda Developmental and Neurologic Examination. Hagerstown, MD: Harper & Row, 1980:17–149.Google Scholar
62. Lammertsma, AA, Bench, CJ, Hume, SP, et al. Comparison of methods for analysis of clinical [C]-raclopride studies. J Cereb Blood Flow Metab 1996;16:42–52.CrossRefGoogle ScholarPubMed
63. Morrish, PK, Sawle, GV, Brooks, DJ. Clinical and [F] dopa PET findings in early Parkinson’s disease. J Neurol Neurosurg Psychiat 1995;59:597–600.CrossRefGoogle ScholarPubMed
64. Plummer, GF. Improved method for the determination of propofol in blood by high performance liquid chromatography with fluorescence detector. J Chromatogr 1987;421:171–176.CrossRefGoogle Scholar
65. Witt-Engerström, I. Age-related occurrence of signs and symptoms in the Rett syndrome. Brain Dev 1992;14 (Suppl):S11–S20.Google ScholarPubMed
66. Kerr, AM, Witt-Engerström, I. The clinical background to the Rett disorder. In: Kerr, A, Witt Engerström I, (Eds.) Rett Disorder and the Developing Brain. Oxford Univ Press, 2000:1–26.Google Scholar
67. Sawle, GV, Playford, ED, Burn, DJ, et al. Separating Parkinson’s disease from normality. Discriminant function analysis of fluorodopa F18 positron emission tomography data. Arch Neurol 1994;51:237–243.CrossRefGoogle Scholar
68. Woods, RP, Mazziotta, JC, Cherry, SR. MRI-PET registration with automated algorithm. J Comput Assist Tomogr 1993;17:536–546.CrossRefGoogle ScholarPubMed
69. Zoghbi, HY, Percy, AK, Glaze, DG, Butler, IJ, Riccardi, VM. Reduction of biogenic amine levels in the Rett syndrome. N Engl J Med 1985;313:921–924.CrossRefGoogle ScholarPubMed
70. Lekman, A, Witt-Engerström, I, Gottfries, J, et al. Rett syndrome: biogenic amines and metabolites in postmortem brain. Pediatr Neurol 1989;5:357–362.CrossRefGoogle ScholarPubMed
71. Motil, KJ, Schultz, RJ, Browning, K, et al. Oropharyngeal dysfunction and gastroesophageal dysmotility are present in girls and women with Rett syndrome. J Pediatr Gastroenterol Nutr 1999;29:31–37.CrossRefGoogle ScholarPubMed
72. Wenk, GL, Naidu, S, Casanova, MF, Kitt, CA, Moser, H. Altered neurochemical markers in Rett syndrome. Neurology 1991;41:1753–1756.CrossRefGoogle Scholar
73. Wenk, GL, O’Leary, M, Nemeroff, CB, et al. Neurochemical alterations in Rett syndrome. Dev Brain Res 1993;74:67–72.CrossRefGoogle ScholarPubMed
74. Lekman, A, Witt-Engerström, I, Holmberg, B, et al. CSF and urine biogenic amine metabolites in Rett syndrome. Clin Genet 1990;37:173–178.CrossRefGoogle ScholarPubMed
75. Villard, L, Kpebe, A, Cardoso, C, et al. Two affected boys in a Rett syndrome family. Clinical and molecular findings. Neurology 2000;55:1188–1193.CrossRefGoogle Scholar
76. Nan, X, Meehan, RR, Bird, A. Dissection of the methyl-CpG binding domain from the chromosomal protein MeCP2. Nucleic Acids Res 1993;21:4886–4892.CrossRefGoogle ScholarPubMed
77. Meloni, I, Bruttini, M, Longo, I, et al. A mutation in the Rett syndrome gene, MECP2, causes X-linked mental retardation and progressive spasticity in males. Am J Hum Genet 2000;67:982–985.CrossRefGoogle ScholarPubMed
78. Moncla, A, Kpebe, A, Missirian, C, Mancini, J, Villard, L. Polymorphisms in the C-terminal domain of MECP2 in mentally handicapped boys: implications for genetic counselling. Eur J Hum Genet 2002;10:86–89.CrossRefGoogle ScholarPubMed
79. Percy, AK. Genetics of Rett syndrome: properties of the newly discovered gene and pathobiology of the disorder. Curr Opin Pediatr 2000;12:589–595.CrossRefGoogle ScholarPubMed
80. Orrico, A, Lam, C-W, Galli, L, et al. MECP2 mutation in male patients with non-specific X-linked mental retardation. FEBS Lett 2000;481:285–288.CrossRefGoogle ScholarPubMed
81. Buyse, IM, Fang, P, Hoon, KT, Amir, RE, et al. Diagnostic testing for Rett Syndrome by DHPLC and direct sequencing analysis of the MECP2 gene: identification of several novel mutations and polymorphisms. Am J Hum Genet 2000;67:1428–1436.CrossRefGoogle ScholarPubMed
82. Alkire, MT, Haier, RJ, Barker, SJ, et al. Cerebral metabolism during Propofol anesthesia in humans studied with positron emission tomography. Anesthesiology 1995;82:393–403.CrossRefGoogle ScholarPubMed
83. Borgeat, A, Wilder-Smith, OHG, Suter, PM. The nonhypnotic therapeutic applications of Propofol. Anesthesiology 1994;80: 642–656.Google ScholarPubMed
84. Schulte, D, Callado, LF, Davidson, C, et al. Propofol decreases stimulated dopamine release in the rat nucleus accumbens by a mechanism independent of dopamine D2, GABA A and NMDA receptors. Br J Anaesth 2000;84:250–253.CrossRefGoogle Scholar
85. Vorsanova, SG, Demidova, IA, Ulas, VY, et al. Cytogenic and molecular-cytogenic investigation of Rett syndrome: analysis of 31 cases. Neuroreport 1996;8:187–189.CrossRefGoogle Scholar
86. Cheadle, JP, Gill, H, Fleming, N, et al. Long-read sequence analysis of the MECP2 gene in Rett syndrome patients : correlation of the disease severity with mutation type and location. Hum Mol Genet 2000;9:1119–1129.CrossRefGoogle ScholarPubMed
87. Rinne, JO, Laihinen, A, Ruottinen, H, et al. Increased density of dopamine D2 receptors in the putamen, but not in the caudate nucleus in early Parkinson’s disease: a PET study with [C]-raclopride. J Neurol Sci 1995;132:156–161.CrossRefGoogle Scholar
88. Rett Syndrome Diagnostic Criteria Work Group. Diagnostic criteria for Rett syndrome. Ann Neurol 1988;23:425–428.CrossRefGoogle Scholar
89. Chan, GL, Doudet, DJ, Dobko, T, et al. Routes of administration and effect of carbidopa pretreatment on 6-[F] fluoro-L-dopa/PET scans in non-human primates. Life Sci 1995;56:1759–1766.CrossRefGoogle ScholarPubMed
90. Perry, TL, Dunn, HG, Ho, HH, Crichton, JU. Cerebrospinal fluid values for monoamine metabolites, gamma aminobutyric acid, and other amino compounds in Rett syndrome. J Pediatr 1988;112:234–238.CrossRefGoogle ScholarPubMed
91. Armstrong, DD. The neuropathology of Rett syndrome: overview 1994. Neuropediatrics 1995;26:100–104.CrossRefGoogle ScholarPubMed
92. Singer, HS, Naidu, SB. Rett syndrome: “We’ll keep the genes on for you”. Neurology 2001;56:582–585.CrossRefGoogle Scholar
93. Bienvenu, T, Carrie, A, DeRoux, N, et al. MECP2 mutations account for most cases of typical forms of Rett syndrome. Hum Mol Genet 2000;9:1377–1384.CrossRefGoogle ScholarPubMed
94. Amir, RE, Van den Veyver, IB, Schultz, R, et al. Influence of mutation type and X chromosome inactivation on Rett syndrome phenotypes. Ann Neurol 2000;47:670–679.3.0.CO;2-F>CrossRefGoogle Scholar
95. Sirianni, N, Naidu, S, Pereira, J, et al. Rett syndrome: confirmation of X-linked dominant inheritance, and localization of the gene to Xq28. Am J Hum Genet 1998;63:1552–1558.CrossRefGoogle ScholarPubMed
96. Dunn, HG. Importance of Rett syndrome in child neurology. Brain Dev 2001; 23:S38–S43.CrossRefGoogle ScholarPubMed
97. Leonard, H, Silverstein, J, Falk, R, et al. Exploring the male phenotype. World Congress on Rett Syndrome 2000. Abstract PO-3:34.Google Scholar
98. Yusufzai, TM, Wolffe, AP. Functional consequences of Rett syndrome mutations on human MeCP2. Nucleic Acids Res 2000;28:4172–4179.CrossRefGoogle ScholarPubMed
99. Topcu, M, Akyerli, C, Sayi, A, et al. Somatic mosaicism for a MeCP2 mutation associated with classic Rett syndrome in a boy. Eur J Hum Genet 2002;10:77–81.CrossRefGoogle ScholarPubMed
100. Xiang, F, Buervenich, S, Nicolao, P, et al. Mutation screening in Rett syndrome patients. J Med Genet 2000;37:250–255.CrossRefGoogle ScholarPubMed
101. Klauck, SM, Lindsay, S, Beyer, KS, et al. A mutation hotspot for nonspecific X-linked mental retardation in the MECP2 gene causes the PPM-X syndrome. Am J Hum Genet 2002;70:1034–1037.CrossRefGoogle Scholar
102. Stenbom, Y, Witt-Engerström, I, Hagberg, B. Gross motor disability and head growth in Rett syndrome. Neuropediatrics 1995;26:85–86.CrossRefGoogle ScholarPubMed
103. Johnston, MV, Hoon, AH Jr. Possible mechanisms in infants for selective basal ganglia damage from asphyxia, kernicterus, or mitochondrial encephalopathies. J Child Neurol 2000;15:588–591.CrossRefGoogle ScholarPubMed
104. Nellhaus, G. Head circumference from birth to 18 years. Practical composite international and interracial graphs. Pediatrics 1968;41:106.CrossRefGoogle Scholar
105. Knobloch, H, Pasamanick, B, eds. Gesell and Amatruda’s Developmental Diagnosis: The Evaluation and Management of Normal and Abnormal Neuropsychologic Development in Infancy and Early Childhood. 3rd ed, Hagerstown, MD: Harper & Row, Inc, 1974.Google Scholar
106. Auranen, M, Vanhala, R, Vosman, M, et al. MECP2 gene analysis in classical Rett syndrome and in patients with Rett-like features. Neurology 2001;56:611–617.CrossRefGoogle ScholarPubMed