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PubMedDate not supplied

The influence of acetylcholine and atropine on the temporary connection in neuronal populations of the motor cortex.

The activity of neurons of the sensorimotor cortex during the paired combination of stimulations of brain structures (the medial lemniscus, the reticular nucleus of the midbrain tegmentum, and the pyramidal tract), with an interstimulus interval of 1.2 sec, was investigated in awake nonimmobilized rabbits. During the omission of the reinforcing stimulus at a place of its expected delivery, a complicated complex of reorganizations of the impulse activity of the neurons develops, consisting of the reproduction of responses and changes in impulse activity which differ in configuration from them, and which usually appear at later periods. The direct application of acetylcholine to the cortex facilitates the manifestation of both types of reorganizations of the neuronal activity. The application, on the other hand, of atropine suppresses primarily the second type of reorganizations. In addition, acetylcholine increases the total duration of these electrical indices of the temporary connection of the developed reactions, while atropine decreases it.

Acetylcholine↗
PubMed1982

Primary brain stem tumours.

The material consisted of 31 patients with primary brain stem tumours who were investigated retrospectively. Twenty patients were younger than 16 years of age (range: 1 1/2-65 years). The mean age was 11 years. The female/male sex ratio was 19/12. Histological diagnoses were available for 18 patients. All of the verified tumours were gliomas. The diagnoses in 12 cases were made by section or biopsy; in 15 by standard clinical and radiological examinations and in 4 by exploratory operations. Headaches, mental changes, speech and gait disturbances were the most common symptoms at the onset of the illness and at the time of diagnosis. The mean latency period between the emergence of symptom(s) until diagnosis was 4 months (range: 1/2-48 months). Amongst the dominant objective findings were failure of the V, VI and VII cranial nerves, pyramidal tract symptoms, ataxia and nystagmus, occurring singly or in combination. Pneumoencephalograms disclosed characteristic changes in 25 patients (83%). Fourteen patients (45%) received radiation treatment, from which 5 (36%) obtained a temporary remission in their symptoms. The postdiagnostic mean survival period for the patients was 15 months (range: 0-92 months). The survival time was found to depend on the number of damaged cranial nerve nuclei at the time of diagnosis and on the degree of severity and duration of the accompanying hydrocephalus. The prognosis was unfavourable, as the percentage of patients who survived for 2 years was only 6%, and a total duration of illness longer than 2 years occurred in only 7 patients. None of the patients were still surviving at the conclusion of this investigation.

Adolescent↗
PubMed1996

Atypical vitamin B12-unresponsive methylmalonic aciduria in sibship with severe progressive encephalomyelopathy: a new genetic disease?

UNLABELLED: We report on two siblings, a girl of 7 years and a boy of 2 years, who presented in infancy with hypotonia, athetoid movements, myopathy and severe developmental delay. The progressive clinical course was characterized by ophthalmoplegia, pyramidal tract signs, loss of visual contact and failure to thrive. The older sister died at the age of 7 years. The younger brother followed an almost identical clinical course. MRI of the brain revealed bilateral hypodensities and atrophy of the putamen. Neurophysiological investigations were consistent with peripheral neuropathy. Investigations for neurometabolic disorders in urine, plasma and CSF of both patients revealed a consistent increase of methylmalonic acid in urine, plasma and CSF as well as borderline low free GABA in CSF. Except for an inconstant elevation of lactate in the boy, metabolic acidosis, hypoglycaemia, episodic ketoacidosis, or hyperammonaemia, the usual concomitants of organoacidopathies, were absent in both children. Homocystinuria was excluded. Methylmalonic aciduria did not respond to antibiotic treatment, vitamin B12 therapy nor dietary protein restriction. Incorporation of [14C]propionate into protein in cultured fibroblasts was pathologically but inconsistently decreased. Both patients' cell lines showed only minimal response to hydroxocobalamin and normal methylmalonyl-CoA mutase activity. CONCLUSION: Even though the definitive underlying enzymatic defect in this sibship remains obscure our results suggest a new genetic disorder. This report illustrates that hitherto undescribed metabolic disorders remain to be elucidated even in long investigated areas of intermediary metabolism such as methylmalonic aciduria.

Amino Acid Metabolism, Inborn Errors↗
PubMed1995

Adrenoleukodystrophy: CT and MRI findings.

A case of adrenoleukodystrophy (ALD) with CT and MRI findings is described. The CT scan showed low densities in the white matter of the parietal and occipital lobes. No calcifications were seen. Post-contrast CT showed an abnormal enhancement within the involved white matter. MRI showed changes of demyelination around the atria of the lateral ventricles bilaterally involving the posterior aspect of the cerebrum symmetrically. The posterior part of the posterior corpus callosum, splenium and pyramidal tracts also showed increased signal intensity. From a review of the literature, these findings are typical of the radiological changes seen in ALD. ALD can be diagnosed from typical history and biochemical changes as well as from CT and MRI findings.

Adrenoleukodystrophy↗
PubMed1996

Spinal MRI in progressive myeloneuropathy associated with vitamin E deficiency.

We describe a patient with a progressive neurological disorder consisting of ataxia, loss of proprioception and pyramidal tract dysfunction in his sixth decade. He had severe vitamin E deficiency due to fat malabsorption secondary to chronic inflammatory bowel disease. Sural nerve biopsy revealed a reduced number of myelinated fibres. MRI of the cervical spine showed high-signal lesions on T2-weighted images in the posterior columns, correlating well with the clinical findings.

Biopsy↗
PubMed1997

Preferential activation of different I waves by transcranial magnetic stimulation with a figure-of-eight-shaped coil.

Transcranial magnetic stimulation (TMS) over the human primary motor cortex (MI) evokes motor responses in the contralateral limb muscles. The latencies and amplitudes of those responses depend on the direction of induced current in the brain by the stimuli (Mills et al. 1992, Werhahn et al. 1994). This observation suggests that different neural elements might be activated by the differently directed induced currents. Using a figure-of-eight-shaped coil, which induces current with a certain direction, we analyzed the effect of direction of stimulating current on the latencies of responses to TMS in normal subjects. The latencies were measured from surface electromyographic responses of the first dorsal interosseous muscles and the peaks in the peristimulus time histograms (PSTHs) of single motor units from the same muscles. The coil was placed over the MI, with eight different directions each separated by 45 degrees. Stimulus intensity was adjusted just above the motor threshold while subjects made a weak tonic voluntary contraction, so that we can analyse the most readily elicited descending volley in the pyramidal tracts. In most subjects, TMS with medially and anteriorly directed current in the brain produced responses or a peak that occurred some 1.5 ms later than those to anodal electrical stimulation. In contrast, TMS with laterally and posteriorly directed current produced responses or a peak that occurred about 4.5 ms later. There was a single peak in most of PSTHs under the above stimulation condition, whereas there were occasionally two peaks under the transitional current directions between the above two groups. These results suggest that TMS with medially and anteriorly directed current in the brain readily elicits I1 waves, whereas that with laterally and posteriorly directed current preferentially elicits I3 waves. Functional magnetic resonance imaging studies indicated that this direction was related to the course of the central sulcus. TMS with induced current flowing forward relative to the central sulcus preferentially elicited I1 waves and that flowing backward elicited I3 waves. Our finding of the dependence of preferentially activated I waves on the current direction in the brain suggests that different sets of cortical neurons are responsible for different I waves, and are contrarily oriented. The present method using a figure-of-eight-shaped coil must enable us to study physiological characteristics of each I wave separately and, possibly, analyse different neural elements in MI, since it activates a certain I wave selectively without D waves or other I waves.

Adult↗
PubMedDate not supplied

Clinical-neurophysiological features of motor lesions in patients with post-stroke epilepsy.

Twenty-two patients with post-stroke epilepsy (group 1) were studied, along with 30 stroke patients without epilepsy (group 2). Bilateral (on both the paralyzed and intact sides) decreases in the central conduction time (CCT) along the pyramidal tract were found in group 1, which were not seen in group 2, who had similarly severe motor lesions (p < 0.01). The tendency to decreased CCT was also seen 5-6 days after ischemic stroke in patients without epileptic manifestations, though CCT in this group increased by day 10-14; low values persisted in group 1 for prolonged periods. The facilitation differentiation (deltaF, the difference in CCT between resting and effort conditions) was also found to increase. In patients with post-stroke epilepsy, motor lesions were characterized by higher levels of muscle tone than in other stroke patients, though the levels of paralysis were similar.

Aged↗
PubMedDate not supplied

Endemic cretinism in Sicily.

This work reports the presence of endemic cretinism in a small district located inside an endemic goiter area in north-eastern Sicily, personally described. The study covers 19 mental defectives (11 females and 8 males, mean age 35.8 +/- 15.5 yr) selected on the basis of severe mental retardation recognized by the local doctors. No systematic survey for cretinism was carried out in the total population. Marked mental retardation was evident in all subjects. Nine of them exhibited clinical and biochemical signs of hypothyroidism (myxedematous cretins). The 10 others were clinically euthyroid and had deaf-mutism and/or pyramidal tract dysfunction (neurological cretinism). Familial aggregation of cretinism was also observed. In both myxedematous and neurological cretins and urinary iodine excretion was very low, but not significantly different from that recorded in the euthyroid controls of the same area. The data available do not clarify the pathogenesis of endemic cretinism in Sicily. However, the marked height retardation, the observation of delayed bone maturation and the severity of mental deficiency suggest that thyroid failure was present in early life. The presence of endemic cretinism today in Sicily constitutes a strong argument in favour of the immediate introduction of adequate iodine prophylaxis.

Adolescent↗
PubMed2000

Rapidly progressive aphasia and motor neuron disease: a clinical, radiological, and pathological study of an autopsy case with circumscribed lobar atrophy.

This report concerns an autopsy case of rapidly progressive aphasia and motor neuron disease. The patient was a Japanese woman who was 75 years old at the time of death. The family history did not reveal hereditary burden. She developed language disturbances and difficulty in swallowing at age 74. Neurological examination 1 month after the disease onset revealed motor aphasia without dementia and bulbar sign, followed by muscle weakness of the four extremities. Neuroradiological examination revealed progressive atrophy of the anterior part of the left temporal lobe. She died of respiratory difficulty 10 months after the disease onset. Macroscopically, neuropathological examination showed circumscribed atrophy of the left perisylvian region and, histologically, neuronal loss in the cerebral cortex, including the primary motor area, substantia nigra, brain stem motor nuclei, and anterior horns of the spinal cord, in addition to obvious degeneration of the pyramidal tracts and presence of Bunina bodies. Ubiquitin-immunoreactive neuronal inclusions were present in the hippocampal dentate granular cells and frontotemporal cortical layer II neurons. Based on these clinicopathological findings and a review of the literature, we concluded that our case is the first reported case of amyotrophic lateral sclerosis with dementia that clinically showed rapidly progressive aphasia.

Aged↗
PubMed2004

[Superficial siderosis of the CNS. Case report and literature review].

Superficial siderosis of the central nervous system is caused by destructive deposition of haemosiderin in the leptomeninges and subpial layers of the brain and spinal cord. This deposition is the result of continuous or recurrent, often clinically silent, haemorrhage in the subarachnoid space, eventually without an evident bleeding source. Cerebellar ataxia, progressive bilateral sensorineural hearing loss, pyramidal tract signs, and dementia are the major clinical findings. The diagnosis is supported in vivo by the characteristic symptom constellation,xanthochromic cerebrospinal fluid,and typical MRI findings which show on the surface of the brainstem, cerebellum, cortex, and spinal cord. Early recognition of this rare entity may be of relevance for the further course and prognosis.

Aged↗
PubMed2000

[Typical anticipation in type 7 spinocerebellar ataxia].

Spinocerebellar ataxia type 7 (SCA7) belongs to the category of autosomal dominant cerebellar ataxias (ADCA). The clinical picture is characterised by progressive ataxia and macular degeneration. Other common signs are slow saccades, external ophthalmoplegia, and pyramidal tract signs. The disease is caused by the expansion of an unstable CAG trinucleotide repeat in the gene for ataxin 7 on chromosome 3. SCA7 is a rare disorder. The first case in Germany was described only recently. We report two additional patients, father and son, with the molecular genetic diagnosis of SCA7. The father carries a trinucleotide expansion of 42 CAG repeats, the son 51. Normal alleles range from 7 to 35 CAG repeats. Both patients show the typical picture with progressive ataxia and macular degeneration. We found a pronounced anticipation (earlier disease onset in subsequent generations), which is highly characteristic of CAG repeat disorders.

Adult↗
PubMed1998

[Brain stem glioma].

Brain-stem gliomas occur mainly in childhood and are localized in the mesencephalon, pons and medulla oblongata. Diagnosis is a domain of MRI, requiring T2, T1 and KM. CT shows hemorrhage and calcification well. The criteria are the primary site, size, tumor growth, brain-stem enlargement, delineation, intralesional structure, exophytic components and enhancement. Secondary criteria are herniation, hydrocephalus and liquorgenic seeding. In CT glioma are hypodense, in MRI hyperintense in T2 and hypointense in T1. Enhancement is seen in 25-60% and does not allow differentiation of tumor vs nontumor or gradings. Factors influencing poor outcome are high grade, a short history, cranial nerve involvement, severe brain-stem enlargement, pontine site, diffuse growth and recurrency. The 5-year-survival rate is 30% (after radiation: focal tumors 85%, diffuse 20%). Most frequent are symptoms of brain pressure, cerebellum, cranial nerves and pyramidal tract. There is no agreement on whether biopsy is necessary or not. A diagnosis of tumor is highly suggestive if classical MRI findings fit the clinical history.

Adolescent↗
PubMed2006

Global and local development of gray and white matter volume in normal children and adolescents.

Over the last decade, non-invasive, high-resolution magnetic resonance imaging has allowed investigating normal brain development. However, much is still not known in this context, especially with regard to regional differences in brain morphology between genders. We conducted a large-scale study utilizing fully automated analysis-approaches, using high-resolution MR-imaging data from 200 normal children and aimed at providing reference data for future neuroimaging studies. Global and local aspects of normal development of gray and white matter volume were investigated as a function of age and gender while covarying for known nuisance variables. Global developmental patterns were apparent in both gray and white matter, with gray matter decreasing and white matter increasing significantly with age. Gray matter loss was most pronounced in the parietal lobes and least in the cingulate and in posterior temporal regions. White matter volume gains with age were almost uniform, with an accentuation of the pyramidal tract. Gender influences were detectable for both gray and white matter. Voxel-based analyses confirmed significant differences in brain morphology between genders, like a larger amygdala in boys or a larger caudate in girls. We could demonstrate profound influences of both age and gender on normal brain morphology, confirming and extending earlier studies. The knowledge of such influence allows for the consideration of age- and gender-effects in future pediatric neuroimaging studies and advances our understanding of normal and abnormal brain development.

Adolescent↗
PubMed2004

Adrenomyeloneuropathy, a dynamic progressive disorder: brain magnetic resonance imaging of two cases.

Adrenomyeloneuropathy (AMN) is a phenotype variant of X-linked adrenoleukodystrophy. We present two patients with adult-onset AMN who were initially suspected to have demyelinating disorders radiologically and finally diagnosed on the basis of laboratory data. The brain magnetic resonance images showed abnormal signal intensity at pyramidal tracts and cerebellar hemisphere bilaterally with abnormal enhancement after contrast medium administration. Review of the literature shows that the brain magnetic resonance findings of adrenomyeloneuropathy may include normal brain, tract demyelination, white matter demyelination, or brain atrophy. Disease progression was demonstrated by follow-up imaging.

Adrenoleukodystrophy↗
PubMed2004

HTLV-I carrier with unusual brain MR imaging findings.

We describe unusual brain MR imaging findings in a patient who is an HTLV-I carrier without myelopathy. T2-weighted MR images showed hyperintense signal abnormalities in the pyramidal tract, superior and middle cerebellar peduncles, and decussation of the superior cerebellar peduncles, in addition to subcortical white matter involvement. Diffusion-weighted images also showed hyperintense signal abnormalities in the same regions by T2 shine-through effect.

Brain↗
PubMed2004

Bilateral Wallerian degeneration of the middle cerebellar peduncles due to paramedian pontine infarction: MRI findings.

Wallerian degeneration is a frequent finding in lesions of the pyramidal tract, but has been observed after damage of the other fibre systems as well. Few reports exist about Wallerian degeneration of cerebellar fibres after distant lesions to the axons. Here, we report on a patient who developed degeneration of both middle cerebellar peduncles after a paramedian pontine infarction.

Aged↗
PubMed1996

MRI of adrenoleukodystrophy involving predominantly the cerebellum and brain stem.

A case of adult-onset adrenoleukodystrophy involving predominantly the cerebellum and brain stem is described. The patient was a 30-year-old man with no family history of adrenoleukodystrophy. His neurological symptoms were progressive cerebellar ataxia and spastic paraparesis. CT showed atrophy of the cerebellum and brain stem. MRI disclosed lesions, enhancing partially with gadolinium, in the dentate nuclei and the pyramidal tracts from the internal capsule to the brain stem. The biochemical findings were compatible with typical adrenoleukodystrophy, but the distribution of the lesions on MRI was distinctly different. After steroid administration, the patient's symptoms improved slightly and contrast enhancement of the lesions was markedly reduced.

Adrenoleukodystrophy↗
PubMed1997

MRI of autosomal dominant pure spastic paraplegia.

We examined 16 patients with autosomal dominant pure spastic paraplegia (HSP) and 15 normal controls matched for age and sex using MRI of the brain and spinal cord. Images were assessed qualitatively by two independent radiologists, blinded to the clinical diagnosis. Areas of the brain and corpus callosum on one midsagittal slice and the area of the brain on one axial slice were measured and a "corpus-callosum index" expressing the size of the corpus callosum relative to that of the brain was calculated. Cross-sectional areas and anteroposterior and transverse diameters of the spinal cord at the levels of C 2, C 5, T 3, T 6, T 9 and T 11 were measured. No significant differences between patients and controls were found on qualitative evaluation of the images. The patients had a significantly smaller corpus callosum and "corpus-callosum index" than controls. This finding, not reported previously, might indicate that the disease process in pure HSP is not confined to the spinal cord. The anteroposterior diameters of the spinal cord at T 3 and T 9 were significantly smaller in patients than in controls. This might correspond to the degeneration of the pyramidal tracts and the dorsal columns described at neuropathological examination.

Adult↗