H3F3A K27M mutations in thalamic gliomas from young adult patients.

INTRODUCTION: Mutations in H3F3A, which encodes histone H3.3, commonly occur in pediatric glioblastoma. Additionally, H3F3A K27M substitutions occur in gliomas that arise at midline locations (eg, pons, thalamus, spine); moreover, this substitution occurs mainly in tumors in children and adolescents. Here, we sought to determine the association between H3F3A mutations and adult thalamic glioma. METHODS: Genomic H3F3A was sequenced from 20 separate thalamic gliomas. Additionally, for 14 of the 20 gliomas, 639 genes--including cancer-related genes and chromatin-modifier genes--were sequenced, and the Infinium HumanMethylation450K BeadChip was used to examine DNA methylation across the genome. RESULTS: Of the 20 tumors, 18 were high-grade thalamic gliomas, and of these 18, 11 were from patients under 50 years of age (median age, 38 y; range, 17-46), and 7 were from patients over 50 years of age. The H3F3A K27M mutation was present in 10 of the 11 (91%) younger patients and absent from all 7 older patients. Additionally, H3F3A K27M was not detected in the 2 diffuse astrocytomas. Further sequencing revealed recurrent mutations in TP53, ATRX, NF1, and EGFR. Gliomas with H3F3A K27M from pediatric or young adult patients had similar, characteristic DNA methylation profiles. In contrast, thalamic gliomas with wild-type H3F3A had DNA methylation profiles similar to those of hemispheric glioblastomas. CONCLUSION: We found that high-grade thalamic gliomas from young adults, like those from children and adolescents, frequently had H3F3A K27M.

Further delineation of the clinical spectrum in RNU4ATAC related microcephalic osteodysplastic primordial dwarfism type I.

We describe five patients from three different families with microcephalic osteodysplastic primordial dwarfism type I (MOPD I), which was molecularly confirmed by homozygosity for the g.51G >A and g.55G >A mutations in RNU4ATAC, respectively. The patients showed the classical phenotype and demonstrated in addition variable degrees of gyration abnormalities and malformations of the callosal body with an interhemispheric cyst. One patient also showed underdevelopment of the cerebellar vermis. This confirms that cortical malformations should be considered cardinal manifestations of MOPD I. Oculocutaneous albinism, brain hemorrhage and chilblains have been found to be associated with MOPD I. The present study showed lack of retinal pigmentation in three patients of whom two had an unusually fair complexion of hair and skin. One patient was found to have a hematoma in the left thalamus. This may indicate that both pigmentary abnormalities and vascular anomalies may be part of the phenotype of MOPD I as well.

Compound heterozygosity of the protein S-gene as a cause of severe cerebral sinovenous thrombosis in a 7-year-old child.

The genotype-phenotype relationship of compound heterozygous protein S-deficiency in a 7-year-old girl with reduced protein S-levels and a severe cerebral sinovenous thrombosis is illustrated. In this patient we identified a novel deletion in the protein S-gene causing a compound heterozygous state and subsequently a symptomatic protein S-deficiency. In case of thrombosis analysis of protein S is recommended. Low levels of protein S should be further investigated by molecular diagnostics.

Clinical features of sporadic fatal insomnia.

Recent advances in neuropathology, genotyping, and physiochemical characterization of proteins have allowed for the classification and verification of MM2-thalamic Creutzfeldt-Jakob disease (CJD). CJD is a fatal neurodegenerative illness belonging to the transmissible spongiform encephalopathies, also known as prion diseases. Sporadic CJD is generally classified by the genotype at codon 129 of the prion protein gene and the distinct physiochemical features of the pathologic prion protein (PrP(sc)). The entity is characterized by methionine homozygosity at codon 129, type 2 PrP(sc), and, primarily, thalamic pathology (MM2-thalamic CJD). It shares clinical and pathologic similarities with the genetic prion disorder fatal familial insomnia; the MM2-thalamic phenotype has therefore been called sporadic fatal insomnia (SFI). SFI may also present like other neurodegenerative diseases, and common diagnostic findings that are seen in other forms of sporadic CJD may be absent.

In vivo detection of thalamic gliosis: a pathoradiologic demonstration in familial fatal insomnia.

BACKGROUND: Increasing evidence supports the usefulness of brain magnetic resonance imaging (MRI) for the diagnosis of human prion diseases. From the neuroradiological point of view, fatal familial insomnia is probably the most challenging to diagnose because brain lesions are mostly confined to the thalamus. OBJECTIVE: To determine whether multisequence MRI of the brain can show thalamic alterations and establish pathoradiologic correlations in a patient with familial fatal insomnia. DESIGN: Radioclinical prospective study. We describe a patient with fatal familial insomnia and normal MRI images. Because the MRI study was performed only 4 days before the patient's death, we were able to compare radiological data with the lesions observed at the neuropathologic level. PATIENT: A 55-year-old man with familial fatal insomnia. MAIN OUTCOME MEASURE: Magnetic resonance spectroscopy combined with the measurement of apparent diffusion coefficient of water in different brain areas. RESULTS: The neuroradiological study showed, in the thalamus but not in the other brain regions studied, an increase of apparent diffusion coefficient of water and a metabolic pattern indicating gliosis. These alterations closely correlated with neuropathologic data showing an almost pure gliosis that was restricted to the thalami. CONCLUSION: Considering fatal familial insomnia as a model of thalamic-restricted gliosis, this case demonstrates that multisequences of magnetic resonance can detect prion-induced gliosis in vivo, as confirmed by a neuropathologic examination performed only a few days after radiological examination.

Fast cortical oscillation after thalamic degeneration: pivotal role of NMDA receptor.

We examined electrophysiological and molecular changes of the thalamocortical system after thalamic degeneration in Purkinje cell degeneration (pcd) mice. In pcd mice, neurons in specific thalamic nuclei including the ventral medial geniculate nucleus began to degenerate around postnatal day 50, whereas the visual thalamic nucleus and nonspecific thalamic nuclei remained almost intact. In association with the morphological changes, auditory evoked potentials in the primary auditory cortex (AC) began to decrease gradually. Fast Fourier transform analysis of spontaneous cortical field potentials revealed that fast oscillation (FO) around 25 Hz occurred in the AC but not in the visual cortex. Quantitative mRNA analysis demonstrated that expression of the N-methyl-D-aspartate (NMDA) receptor was up-regulated in the AC but not in the visual cortex. Systemic administration of an NMDA antagonist abolished the FO in the AC. These results indicate that increased NMDA activity may cause the FO in the AC of pcd mice.

Thalamic reductions in children with chromosome 22q11.2 deletion syndrome.

Children with chromosome 22q11.2 deletion syndrome (22q) suffer from physical and behavioral dysfunctions, including neuroanatomical anomalies, visuo-spatial processing deficits, and increased risk for psychopathology. Reduced total brain volume, parietal lobe volume, and cerebellar volumes, enlarged ventricles, and increased basal ganglia volumes have been reported. Since previous literature has related the pulvinar nucleus of the thalamus to visuo-spatial processing, we compared the thalamic volume in children with 22q to typically developing controls. Children with 22q showed a significant reduction of the thalamus compared with normally developing children, specifically in the posterior portion of the thalamus, including the pulvinar nucleus. These results provide the first evidence for a potential relationship between posterior thalamic reductions and the characteristic visuo-spatial deficits demonstrated in this group.

Adult-onset autosomal recessive ataxia with thalamic lesions in a Finnish family.

OBJECTIVE: To describe an unusual kindred with adult-onset ataxia and thalamic lesions detected by brain MRI. METHODS: The authors characterized clinical, laboratory, and pathologic features of the disease and sought linkage to previously recognized ataxia loci. RESULTS: Two sisters and a brother developed progressive ataxia, dysarthria, mild cognitive impairment, and sensorimotor neuropathy at age 30, combined with epilepsy in one sibling. MRI showed symmetric thalamic lesions, changes in brainstem gray matter, and white matter changes in the cerebellum. Autopsy in one of the patients revealed neuronal degeneration with a peculiar vacuolar change in thalamus, probably representing transsynaptic degeneration in response to deafferentation. Neuronal and secondary tract degeneration was observed in the spinal cord, cerebellum, and brainstem suggesting a spinocerebellar degeneration. The disorder appears to be transmitted as an autosomal recessive trait. Genetic and sequence analysis of the FRDA gene and comprehensive laboratory examinations excluded Friedreich's ataxia and other similar recessive diseases. CONCLUSION: Adult-onset recessive ataxia with bilateral thalamic lesions in this family may represent a distinct hereditary spinocerebellar ataxia.

[Primary thalamic hemorrhage penetrating to the lateral ventricle in an infant with abnormal protein S(protein S-Tokushima)].

We experienced a 3 months infant with thalamic hemorrhage penetrating to lateral ventricle with abnormal Protein S. Although the coagulation factor and fibrinogenolysis factors were evaluated, there were no remarkable abnormal laboratory data except for slightly decline of Protein S. The DNA analysis was performed for Protein S, and a missense mutation(A to G transmission) was found, which was resulting in Lys-155 to Glu. The total Protein S antigen was normal level, but co-factor activity for activated Protein C was declined. That mutation is named Protein S-Tokushima, and the patient who has abnormal Protein S tends to suffer recurrent coagulopathy. In our patient, it was interesting that any thrombotic disease had not occurred, but cerebral hemorrhage had occurred.

Antenatal thalamic lesions in the newborn: two anatomoclinical cases.

We report two cases of antenatal bilateral thalamic lesions constituted by neuronal loss, gliosis and mineralized glial or neuronal cells. No etiology could be found. Neuroradiological findings were poorly correlated with histological changes. These cases are compared with the few previously reported cases of the same condition. We strongly recommend extensive etiological investigation as recurrence occurred in one family.

Familial neurofibromatosis 1 with germinoma involving the basal ganglion and thalamus.

Intracranial germinoma associated with neurofibromatosis 1 (NF-1) has never been documented previously. We report a case of familial NF-1 with a germinoma involving the right basal ganglion and thalamus. A 12-year-old boy presented with multiple café-au-lait spots and a family history of neurofibromatosis in his mother, one of two siblings, and his maternal grandfather. His intracranial lesion was subtotally resected. Histologically, it was a pure germinoma. Serum alpha-feto protein and beta-human chorionic gonadotropin levels were within the normal range. Postoperative myelographic examination and cerebrospinal fluid cytology study showed no evidence of subarachnoid seeding. The patient received postoperative combination chemotherapy resulting in complete response and clearance of the residual tumor. Although this finding of an intracranial germinoma in a patient with familial NF-1 may be coincident, it is suggestive of a potential genetic predisposition. Longitudinal evaluation for the possibility of neoplasm, especially germ cell tumor, in basal ganglion lesions in NF-1 patients is necessary.

Dissociated 24-hour patterns of somatotropin and prolactin in fatal familial insomnia.

To assess the changes in the 24-hour profiles of serum somatotropin and prolactin levels during total disruption of the sleep/wake cycle sustained over several months, we studied 2 subjects affected by fatal familial insomnia, a rare disease characterized by selective thalamic degeneration that causes chronic sleep loss. Under standardized conditions and polysomnographic control, the patients underwent repeated 24-hour study sessions covering the entire clinical course of the disease. Hormones were assayed at 30-min intervals. Four healthy volunteers were used as controls. A sleep/wake cycle was always absent in fatal familial insomnia. Serum somatotropin and prolactin concentrations never exceeded the normal range of variation. The nocturnal elevation of somatotropin disappeared simultaneously with sleep loss, whereas a significant 24-hour component of variations in serum prolactin levels was present for months after total disruption of the sleep/wake cycle, with normally placed nocturnal acrophases. Complete obliteration of the 24-hour component was achieved for prolactin only in the advanced stages, through a progressive decrease in 24-hour amplitude of variation. Selective and progressive degeneration of the mediodorsal and anterior ventral nuclei of the thalamus causes an early obliteration of the 24-hour rhythm of somatotropin and a later disappearance of circadian prolactin rhythmicity.(ABSTRACT TRUNCATED AT 250 WORDS)

Infantile progressive striato-thalamic degeneration in two siblings: a new syndrome.

The clinical features, neuroimaging, and neuropathologic findings of a new syndrome, characterized by onset in early infancy, progressive course, choreiform movements, hypotonia, and dysphagia, are described in 2 siblings originating from a consanguineous marriage. The serial neuroimaging studies indicated progressive loss of volume of both caudate nuclei and change in signal intensity in putamina. Pathologically, there was severe neuronal loss and gliosis in the striatum and thalamus. This pathologic pattern in association with clinical and radiologic correlates, to our knowledge, has not been previously described. It appears that this syndrome is an autosomal recessive disorder.

Lack of vegetative and endocrine circadian rhythms in fatal familial thalamic degeneration.

A total lack of neuroendocrine and vegetative circadian rhythms was observed in a patient with a familial degeneration of the anterior and dorso-medial thalamic nuclei. Our findings support the role of the thalamus in regulating the periodicity of endocrine and vegetative functions.

[Familial insomnia with a malignant course: a new thalamic disease]. / Insomnie familiale a évolution maligne: une nouvelle maladie thalamique.

A degenerative familial disease with insomnia and autonomic disorders in a 53 years old man is reported. At post-mortem examination anterior and dorso-medial nuclei of the thalamus were atrophied.