1/34. Genetic factors in human sleep disorders with special reference to Norrie disease, prader-willi syndrome and Moebius syndrome.Sleep-wake problems are common in specific inborn errors of metabolism and structure of the central nervous system. Psychological factors, behavioural difficulties, metabolic disturbances, and widespread rather than focal damage to the nervous system are present in many of these diseases and all influence the sleep-wake cycle. However, a number of conditions cause relatively focal damage to the neuroanatomical substrate of sleeping and waking. These include fatal familial insomnia, with involvement of the prion protein gene on chromosome 20, Norrie disease, the prader-willi syndrome and the Moebius syndrome. The last three important conditions, although rare, are considered in detail in this review. They result in sensory deprivation, hypothalamic and mid-brain damage, and involve the X-chromosome, chromosome 15, and chromosome 13, respectively. These conditions cause a wide variety of sleep disturbance, including parasomnias, daytime sleepiness, and a condition like cataplexy. The place of the relevant gene products in normal sleep regulation needs further exploration.- - - - - - - - - - ranking = 1keywords = central nervous system, brain, nervous system (Clic here for more details about this article) |
2/34. Pontocerebellar hypoplasia associated with respiratory-chain defects.Pontocerebellar hypoplasias are congenital disorders of brain morphogenesis which include such diverse etiologies as carbohydrate-deficient glycoprotein syndrome type 1, cerebromuscular dystrophies (walker-warburg syndrome, Fukuyama syndrome, muscle-eye-brain disease) and at least two types of autosomal recessive neurodegenerations known as pontocerebellar hypoplasia type I and II. Pontocerebellar hypoplasia type 1 is a lethal phenotype and clinical features include congenital contractures, respiratory insufficiency, central and peripheral motor dysfunction and spinal anterior horn degeneration. Type 2 is characterized by progressive microcephaly, extrapyramidal dyskinesia and normal spinal cord findings. In this paper, we describe a girl, born at 33 weeks of gestation, presenting with respiratory insufficiency and multiple contractures. MRI scan of the brain demonstrated pontocerebellar hypoplasia and cortical and diffuse periventricular white matter abnormalities. Postmortem examination showed pontocerebellar hypoplasia with extensive gliosis of the periventricular white matter and of the basal ganglia with normal spinal cord findings. histology of skeletal muscle was normal. Biochemical analysis demonstrated multiple deficiencies of respiratory chain enzymes in skin fibroblasts. This case demonstrates a lethal phenotype of pontocerebellar hypoplasia without spinal cord abnormalities associated with a respiratory-chain disorder. The diagnostic workup in a patient whose brain image shows pontocerebellar hypoplasia should include a search for respiratory-chain impairment.- - - - - - - - - - ranking = 0.89603383833149keywords = brain (Clic here for more details about this article) |
3/34. Olivopontocerebellar atrophy: paraneoplastic syndrome of brain tumour?We describe a patient who, three years after the onset of an olivopontocerebellar atrophy, developed a right cerebral tumour. The cerebellar symptomatology also included, as in other cerebellar patients previously described, a peripheral dysgraphia. Because this deficit of writing is generally reported in patients with right cerebral lesion, the authors hypothesized that functional alterations of supratentorial structures preceding the tumour by years may be able to damage the neural substrates connecting cerebral and cerebellar structures and to produce cerebellar atrophy.- - - - - - - - - - ranking = 0.89603383833149keywords = brain (Clic here for more details about this article) |
4/34. Pontocerebellar hypoplasia type 2: further clinical characterization and evidence of positive response of dyskinesia to levodopa.Pontocerebellar hypoplasia type 2 (PCH2) is a very rare autosomal recessive disorder. We report two unrelated female patients born to consanguineous parents presenting with this condition. Patient 1 showed a classical clinical/neuroradiological phenotype of PCH2 with dyskinesia/dystonia. Patient 2 had a neonatal onset of PCH2 with polyhydramnios, apneic spells, myoclonus, and an akinetic/rigidity condition. Neuroradiologically, patient 2 showed extensive pancerebral degeneration. Based on these observations, and in accordance with the published cases, two groups of PCH2 patients may be defined: (a) patients with dyskinesia/dystonia, severe hypoplasia of the infratentorial structures and less severe involvement of the supratentorial brain; and (b) patients with polyhydramnios, neonatal onset with tremulousness (hyperekplexia), no spontaneous activity, absence of dyskinesia and pancerebral degeneration. Finally, we report a dramatic positive response of the patient with dyskinesia/dystonia to levodopa treatment, and discuss the associated physiopathological implications.- - - - - - - - - - ranking = 0.22400845958287keywords = brain (Clic here for more details about this article) |
5/34. Bilateral high-frequency synchronous discharges: a new form of tremor in humans.OBJECTIVES: To report bilateral high-frequency synchronous discharges in a patient with a sporadic form of olivopontocerebellar atrophy; to investigate the electromyographic pattern, the coherence and cospectral density across limbs, and the resetting effects of electrical stimulation over the posterior fossa; and to highlight the clinical, electrophysiologic, and radiologic features of this new form of tremor associated with posterior fossa disorders. DESIGN: Case study of a patient clinically exhibiting a sporadic form of olivopontocerebellar atrophy associated with cerebellar and brainstem atrophy. SETTING: research unit, university hospital. MAIN OUTCOME MEASURES: Electromyographic studies, coherence and cospectral density analysis, and calculation of a resetting index based on the timing of measured bursts and predicted bursts for an electrical stimulus given over the posterior fossa at increasing delays. RESULTS: Surface electromyographic recordings in forearm muscles revealed a low-frequency postural tremor in the upper limbs, with episodes of highly coherent tremor at a frequency of 14 Hz. Squared coherence and cospectral density was strong between agonist and antagonist muscles in the left and right upper limbs and across limbs for the high-frequency discharges. Electrical stimulation over the posterior fossa reset the explosive high-frequency bursts. The resetting index was 0.82 Hz. CONCLUSIONS: Our results show that bilateral high-frequency synchronous discharges may be associated with the sporadic form of olivopontocerebellar atrophy. Bilateral coherent bursting and resetting of this explosive postural tremor following electrical stimulation over the posterior fossa strongly suggest that the brainstem plays a key role in the network involved in the genesis of rhythmic bursts. We suggest that the high-frequency discharges are due to repetitive discharges in the reverberating cerebello-precerebellar circuits.- - - - - - - - - - ranking = 0.44801691916575keywords = brain (Clic here for more details about this article) |
6/34. magnetic resonance imaging of degenerative diseases of the central nervous system.MRI enables a better assessment than CT of the bulk loss, i.e. atrophy, which is a characteristic feature of all the degenerative diseases of CNS, at least in their advanced phases. Moreover, in several of these disorders, proton density, balanced and T2 weighted MR images can show symmetric areas of abnormally low or high signal intensity in the deep gray nuclei or white matter. Since these signal abnormalities are not specific of degenerative diseases of the CNS, their shape and distribution have to match those of the histopathological changes characteristic of each disease, before they could represent useful ancillary signs. Combination of the above MRI findings with appropriate clinical and laboratory features will however be crucial to the diagnosis in any single case.- - - - - - - - - - ranking = 2.2755865000879keywords = central nervous system, nervous system (Clic here for more details about this article) |
7/34. An autopsy case of early ("minimal change") olivopontocerebellar atrophy (multiple system atrophy-cerebellar).We report a 57-year-old woman with multiple system atrophy (MSA) of 15-month duration. The patient developed dysarthria, followed by impaired balance of gait, mild limb ataxia, and saccadic eye movement. A postmortem examination performed after she was found dead in a bathtub revealed neuronal loss restricted to the olivopontocerebellar system, being more severe in the pontine nucleus. Mild neuronal loss was also found in the anterior vermis and inferior olivary nucleus. alpha-synuclein immunohistochemistry demonstrated widespread occurrence of glial cytoplasmic inclusions in the central nervous system, which were more numerous in the pontine base and cerebellar white matter. In contrast, neuronal alpha-synuclein accumulation was confined to the pontine and inferior olivary nuclei. The number of neuronal intranuclear inclusions was much higher than that of neuronal cytoplasmic inclusions. Moreover, alpha-synuclein accumulation was more severe in the neurites than in the cytoplasm or nucleus. This case demonstrates the early pattern of brain pathology in MSA-cerebellar (olivopontocerebellar atrophy).- - - - - - - - - - ranking = 0.79290508460484keywords = central nervous system, brain, nervous system (Clic here for more details about this article) |
8/34. X-linked adrenoleukodystrophy with olivopontocerebellar atrophy.X-linked adrenoleukodystrophy (X-ALD) is a rare neurological disorder characterized by adrenal, gonadal and nervous system dysfunction. patients usually develop spinal cord degeneration with involvement of the cerebral white matter. While a spinocerebellar variant has been described, the selective involvement of cerebellar white matter is very rare. We report the case of a patient affected by X-ALD whose clinical and magnetic resonance imaging (MRI) results resembled olivopontocerebellar atrophy. He was a 29-year-old mentally retarded man, who began to complain of slowly progressive gait ataxia after an 8-year history of Addison's disease. Serial MRI revealed marked cerebellar atrophy involving the inferior cerebellar vermis and brainstem, but sparing the supratentorial white matter. The diagnosis of X-ALD was confirmed by elevated levels of very long-chain fatty acids in the serum. After 2 years follow-up, the patient developed spastic paraparesis. The patient represents an unusual clinical presentation of X-ALD, as further confirmed by the MRI results. Consequently, cerebellar symptoms should be considered as a clinical presentation of X-ALD. Early recognition of this rare disorder would be useful for genetic counselling and therapy.- - - - - - - - - - ranking = 0.43110337497803keywords = brain, nervous system (Clic here for more details about this article) |
9/34. Severe, fetal-onset form of olivopontocerebellar hypoplasia in three sibs: PCH type 5?We present three siblings with a precise onset of fetal seizure-like activity who had severe olivopontocerebellar hypoplasia (OPCH) and degeneration. Autopsies at 20, 27, and 37 weeks gestation showed diffuse central nervous system volume loss that was most marked for the cerebellum and brain stem structures. Neuropathological abnormalities included dysplastic, C-shaped inferior olivary nuclei, absent or immature dentate nuclei, and cell paucity more marked for the cerebellar vermis than the hemispheres. Delayed development was seen in layer 2 of the cerebral cortex and in purkinje cells of the cerebellum. Prenatal monitoring defined a developmental window of 16-18 weeks gestation when ultrasonic assessment of cerebellar width was used for prenatal diagnosis. We discuss our findings in the context of the differential diagnosis for infantile (O)PCH and propose a classification scheme for the pontocerebellar hypoplasias. These patients represent the earliest reported with OPCH and provide unique information regarding the developmental neuropathology of this condition.- - - - - - - - - - ranking = 0.79290508460484keywords = central nervous system, brain, nervous system (Clic here for more details about this article) |
10/34. Multiple system degeneration with glutamate dehydrogenase deficiency: pathology and biochemistry.The neuropathological findings in a patient with antemortem diagnosis of olivopontocerebellar atrophy (OPCA) and reduced leucocytic glutamate dehydrogenase (GDH) activity included cerebellar cortical degeneration, most marked in the superior vermis, mild atrophy of the pons and the inferior olivary nucleus, marked reduction of anterior horn cells at all levels and gliosis in both lateral columns. GDH activities and their thermolability in "soluble" and "particulate" fractions in the cerebral cortex, cerebellar hemisphere and vermis were not significantly different from the values in two control brains. GDH mRNA in the patient's brain was not altered in size or amount.- - - - - - - - - - ranking = 0.44801691916575keywords = brain (Clic here for more details about this article) |
| | Next -> |