bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Unusual Form of Motor Neuron Disease Following a Cat Bite
Authors: Hudson Arthur J. , Vinters Harry V. , Povey R. Charles , Hatch Leslie A. , Percy Dean H. , Noseworthy John H. , Kaufmann John C.E. 
Published: July 2016

ABSTRACT:A case of motor neuron disease with clinical and pathological resemblance to amyotrophic lateral sclerosis (ALS) in a woman who was severely bitten on the ankle by a cat is described. Weakness first appeared at the ankles and relentlessly advanced proximally, terminating in death from pulmonary failure in a year. A number of unusual features that are uncharacteristic of ALS were found that included a markedly elevated antinuclear antibody titre in the serum and the presence of prominent oligoclonal bands in the cerebrospinal fluid. The spinal cord showed loss of anterior horn cells and pyramidal degeneration that are characteristic of ALS, but an extraordinary finding was the presence of transmural granulomatous inflammation of numerous small and medium sized vessels, especially veins, in the subarachnoid space around the cord. There were also inflammatory changes in the brainstem and spinal cord consisting of microglial and astrocytic nodules and perivenous cuffing by mononuclear cells. Ill-defined hyaline eosinophilic cytoplasmic inclusions were seen in some remaining anterior horn cells. No viral particles were found by electron microscopy despite an extensive search. Virological studies were inconclusive but there is reason to believe that this patient's illness was caused by an as yet unidentified virus.
Parkinson's Disease: A Genetic Study
Authors: Alonso Ma. Elisa , Otero Enrique , D'Regules Rosalinda , Figueroa Hector Hugo 
Published: July 2016

ABSTRACT:A sample of 122 patients with Parkinson's Disease was studied for the purpose of investigating if the frequency of relatives affected with Parkinson in this group was higher than in a control group and to see if the genetic load was more important in some of the subtypes of Parkinson described by Barbeau and Pourcher (1982).7In our 122 patients, we found that 1.7% were post-encephalic parkinsonian, 12.3% were symptomatic cases and 86% of the idiopathic variety. There were 16.1% early onset patients in the idiopathic group and among these we found 23.5% with a positive family history of Parkinson in the first-degree relatives. In 6 cases with the tremor onset form of the disease, the family history was positive and 5 patients, 4.7% had familial essential tremor-related Parkinsonism. Our results support Barbeau's hypothesis7.19that Parkinson is a heterogeneous disease in which some subtypes (such as early onset Parkinson) have an important genetic subceptibility component.
Differential Diagnosis of the Dementias of Unknown Origin: A Clinician's View
Authors: Kral V.A. 
Published: July 2016

Abstract:The close cooperation of clinical and laboratory research has helped to clarify the etiology of some of the dementing processes of the senium. However, the necessary investigations are complicated, laborious, expensive and can be carried out only in well equipped centres in larger cities. This restricts the number of patients who eventually may benefit from these investigations to a small number. What is needed for the psychogeriatric practice particularly in rural areas and smaller cities are simple diagnostic guidelines for the psychiatrist to answer the question whether the patient suffers from a dementia and if so whether the dementia is in all probability due to a primary degenerative process of the brain parenchyma or of the cerebral vasculature or is it due to another cause.If degeneration of the brain parenchyma seems the prevalent pathogenetic mechanism one would like to establish in a given case which of the known degenerative processes is most probably present in order to avoid mistakes in clinical judgement with their often life threatening consequences.
Cell Loss from the Nucleus Basalis of Meynert in Alzheimer's Disease
Authors: Doucette R. , Fisman M. , Hachinski V.C. , Mersky H. 
Published: July 2016

Abstract:We examined the degree of neuronal loss from the nucleus basalis of Meynert (nbM) in two groups of Alzheimer patients differing in the degree of intellectual impairment. Significant cell loss from the nbM was found only in the more severely demented group of patients. Mean cell counts (per lOu, paraffin section) were compiled separately for the anterior, intermediate and posterior subdivisions of the human nbM in three groups of subjects: Group 1 (N = 4) was severely demented and was untestable on the Extended Scale for Dementia (ESD) for at least the last two years of life; Group 2 (N = 4) was less demented and had completed at least one ESD test within 12 months of death; Group 3 (five controls) had died of non-neurological causes. In Group 2 there was a small (but insignificant) trend toward cell loss in the anterior subdivision, and a normal complement of neurons in both the intermediate and posterior subdivisions. There was, however, significant cell loss from all subdivisions of Group 1. How these cell counts may relate to the severity of the dementia is discussed.
Failed Compensatory Dendritic Growth as a Pathophysiological Process in Alzheimer's Disease
Authors: Flood Dorothy G. , Coleman Paul D. 
Published: July 2016

Abstract:In normal human aging the remaining neurons of two areas of the hippocampal region have been found to compensate for age-related neuronal loss by proliferating new dendrites. In Alzheimer's disease (AD) the layer II pyramidal neurons of the parahippocampal gyrus fail to show this compensatory response, in spite of a probable, exaggerated disease-related loss of neurons. In AD the dentate gyrus granule cells of the hippocampus also show a reduced amount of the compensatory response. This failure of the AD brain to show the normal compensatory plastic response, seen in normal aging as dendritic growth, may be viewed as one of the pathophysiological processes of the disease.
Clinicopathological Studies of Some Non-Alzheimer Dementing Diseases
Authors: Munoz-Garcia David , Ludwin Samuel K. 
Published: July 2016

Abstract:The brains of most demented patients show at autopsy the lesions of Alzheimer's disease (AD). However, the brains of other demented patients show either no morphological changes or lesions distinct from those of AD. We report clinicopathological studies on two diseases in this latter group. The study of these diseases can improve our understanding of AD.Pick's disease is characterized by dementia, lobar cerebral atrophy, and neuronal cytoplasmic inclusions. Most cases, which we have called “classical”, show inclusions made up of straight fibrils that are immunologically cross-reactive with the paired helical filaments of AD. In other “generalized” cases, similar fibrils are coated by granular material and are less reactive with anticytoskeletal antibodies.In contrast to the cytoplasmic localization of the lesions in Pick's disease, it is the cell nucleus that shows abnormalities in neuronal intranuclear hyaline inclusion disease. This disease can present clinically as dementia of adult onset. Thus, either nuclear or cytoplasmic lesions can produce a pattern of neuronal dysfunction resulting in dementia.
Neurotransmitter and Receptor Deficits in Senile Dementia of the Alzheimer Type
Authors: Quirion R. , Martel J.C. , Robitaille Y. , Etienne P. , Wood P. , Nair N.P.V. , Gauthier S. 
Published: July 2016

Abstract:Multiple neurotransmitter systems are affected in senile dementia of the Alzheimer's type (SDAT). Among them, acetylcholine has been most studied. It is now well accepted that the activity of the enzyme, choline acetyltransferase (ChAT) is much decreased in various brain regions including the frontal and temporal cortices, hippocampus and nucleus basalis of Meynert (nbm) in SDAT. Cortical M2-muscarinic and nicotinic cholinergic receptors are also decreased but only in a certain proportion (30-40%) of SDAT patients. For other systems, it appears that cortical serotonin (5-HT)-type 2 receptor binding sites are decreased in SDAT. This diminution in 5-HT2 receptors correlates well with the decreased levels of somatostatin-like immunoreactive materials found in the cortex of SDAT patients. Cortical somatostatin receptor binding sites are decreased in about one third of SDAT patients. Finally, neuropeptide Y and neuropeptide Y receptor binding sites are distributed in areas enriched in cholinergic cell bodies and nerve fiber terminals and it would be of interest to determine possible involvement of this peptide in SDAT. Thus, it appears that multi-drug clinical trials should be considered for the treatment of SDAT.
Alzheimer's Disease: Metabolic Uncoupling of Associative Brain Regions
Authors: Rapoport Stanley I. , Horwitz Barry , Haxby James V. , Grady Cheryl L. 
Published: July 2016

Abstract:Evidence indicates that Alzheimer's disease (AD) causes functional disconnection of neocortical association areas. In mildly demented AD patients without measurable neocortically-mediated cognitive abnormalities, positron emission tomography demonstrates reduced parietal lobe glucose metabolism and left/right metabolic asymmetries in neocortical association areas. Similar metabolic abnormalities occur in moderately demented patients, but are accompanied by appropriate language and visuospatial discrepancies. Left/right metabolic asymmetries correspond with reduced numbers of partial correlations between metabolic rates in homologous right and left regions, and in the frontal and parietal cortices, indicating metabolic uncoupling among these regions. The affected association regions are those which demonstrate Alzheimer-type neuropathology post-mortem.
Magnetic Resonance Imaging in Down's Syndrome
Authors: Pelz David M. , Karlik Stephen J. , Fox Allan J. , Viñuela Fernando 
Published: July 2016

Abstract:100% of brains of Down's adults over age 40 will show Alzheimer-type neuropathologic changes in the frontal and temporal lobes. In an attempt to image these lesions, magnetic resonance imaging (MRI) was performed in seven patients with Down's syndrome, ranging in age from 17 to 45 years, using a resistive unit operating at 0.15 Tesla. All scans were within normal limits except for one 45 year-old patient with severe left temporal lobe atrophy. No areas of abnormal signal were seen in the frontal or temporal lobes and the white matter lesions commonly seen in elderly demented subjects were not visualized in this group. We conclude that these white matter lesions are likely coincidental and not causally related to Alzheimer's changes. The pathologic process leading to the formation and development of Alzheimer's changes in the brains of Down's adults may not be visible on magnetic resonance images.
Observations About Amyotrophic Lateral Sclerosis and the Parkinsonism-Dementia Complex of Guam with Regard to Epidemiology and Etiology
Authors: Steele John C. , Guzman Tomasa 
Published: July 2016

ABSTRACT:For more than 150 years, Chamorro natives of the Mariana Islands in the Western Pacific Ocean, have developed fatal paralysis in middle and later life, which we term amyotrophic lateral sclerosis/parkinsonism-dementia (ALS/PD). The cause of the disease might be exposure to seeds of the indigenous cycad. Motor system disease is induced in cynomolgus monkeys by feeding them beta-N-methylamino-L-alanine (BMAA), an amino acid present in cycad seeds. We believe that the cycad seeds which usually cause no immediate adverse symptoms when prepared and eaten as flour, or applied topically as medicine, can give rise to widespread and severe nerve cell degeneration after a latency of many decades. Furthermore, it may be that only a single exposure to this potent but silent toxin(s) can result in fatal neurological disease years later.
Cognition and the Basal Ganglia: A Possible Substrate for Procedural Knowledge
Authors: Phillips Anthony G. , Carr Geoffrey D. 
Published: July 2016

ABSTRACT:Disruption of neural activity within the basal ganglia of experimental animals causes selective learning deficits in tasks requiring switching between response strategies. These data along with reports of both general and specific intellectual impairment in patients with neurodegenerative disorders such as Parkinson's disease, appear to support the theory of cognitive functions of the basal ganglia. Recent studies have failed to confirm general cognitive or memory deficits in parkinsonian patients, but have identified deficiencies in devising and executing certain cognitive strategies. Following the lead of theorists such as Squire and Mishkin, this brief review emphasizes the distinction between procedural and declarative knowledge and examines the possible role of the basal ganglia in the acquisition and retention of procedural knowledge.
Neurotransmitters in the Mammalian Striatum: Neuronal Circuits and Heterogeneity
Authors: Semba K. , Fibiger H.C. , Vincent S.R. 
Published: July 2016

ABSTRACT:The major input and output pathways of the mammalian striatum have been well established. Recent studies have identified a number of neurotransmitters used by these pathways as well as by striatal interneurons, and have begun to unravel their synaptic connections. The major output neurons have been identified as medium spiny neurons which contain ɣ-aminobutyric acid (GABA), endogeneous opioids, and substance P. These neurons project to the pallidum and substantia nigra in a topographic and probably chemically organized manner. The major striatal afferents from the cerebral cortex, thalamus, and substantia nigra terminate, at least in part, on these striatal projection neurons. Striatal interneurons contain acetylcholine, GABA, and somatostatin plus neuropeptide Y, and appear to synapse on striatal projection neurons. In recent years, much activity has been directed to the neurochemical and hodological heterogeneities which occur at a macroscopic level in the striatum. This has led to the concept of a patch-matrix organization in the striatum.
Receptors in the Basal Ganglia
Authors: Guttman Mark 
Published: July 2016

ABSTRACT:The study of neurotransmitter receptors aids in the understanding of the normal anatomy, pharmacology, therapeutics and pathophysiology of disease processes involving the basal ganglia. Receptors may be studied in vitro by homogenate binding experiments, enzyme analysis or quantitative autoradiography and in vivo with positron emission tomography. In the substantia nigra (SN), receptors have been identified for somatostatin, neurotensin, substance P, glycine, benzodiazepine and GABA, opiates, dopamine, angiotensin converting enzyme (ACE) and serotonin. The striatum has receptors for dopamine, GABA and benzodiazepines, acetylcholine, opiates, substance P, glutamate and cholecystokinin. GABA and benzodiazepine receptors are also located in the globus pallidus. In Parkinson's disease, striatal dopamine D-2 receptors are elevated in patients that have not received L-DOPA therapy. This supersensitivity is reversed with agonist therapy. Muscarinic binding to cholinergic receptors seems to correlate with dopamine receptors. Delta opiate receptors are increased in the caudate and mu binding is reduced in the striatum. In the SN of patients with Parkinson's disease, there is reduced binding of somatostatin, neurotensin, mu and kappa opiates, benzodiazepine and GABA and glycine. In Huntington's disease, there is reduced binding of GABA and benzodiazepines, dopamine, acetylcholine, glutamate and CCK. There is increased binding of GABA in both the SN and globus pallidus. Glycine binding is increased in the substantia nigra and ACE is reduced.
MPTP-Induced Parkinsonism in the Monkey: Neurochemical Pathology, Complications of Treatment and Pathophysiological Mechanisms
Authors: Crossman A.R. , Clarke C.E. , Boyce S. , Robertson R.G. , Sambrook M.A. 
Published: July 2016

ABSTRACT:MPTP induces parkinsonism in monkeys by destruction of the substantia nigra, pars compacta. It can also damage ventral tegmental dopamine neurones and the noradrenergic locus coeruleus, both of which may be affected in Parkinson's disease. Motor symptoms in MPTP-treated monkeys respond readily to levodopa or dopamine agonist therapy. Administration of levodopa over 4-8 weeks leads to the emergence of “peak- dose” dyskinesia. Such abnormal movements are not seen following challenge doses of levodopa in animals not on long-term therapy. Radioligand studies reveal a 40-180% increase in D2 receptor binding in the striatum of parkinsonian monkeys. 2-deoxyglucose studies of regional brain metabolism indicate that MPTP-induced parkinsonism is characterised by abnormally increased activity of medial pallidal neurones which project to the thalamus and pedunculopontine nucleus and reduced activity of subthalamic nucleus neurones.
A Rostrocaudal Gradient for Aromatic Acid Decarboxylase in the Human Striatum
Authors: Garnett E.S. , Lang A.E. , Chirakal R. , Firnau G. , Nahmias C. 
Published: July 2016

ABSTRACT:The local concentration of 6-[18F]fluoro-L-dopa (18F) reflects the activity of aromatic acid decarboxylase (AADC), the enzyme that generates dopamine from its precursor amino acid, L-dopa. In young healthy adults, the local concentration of 18F, and hence AADC activity, is constant in coronal slices taken in a rostrocaudal direction. With increasing age a gradient representing decreasing activity in the putamen develops. This decrease is less marked than was expected from the literature. In five children with primary dystonia, the striatal distribution of 18F resembled that seen in the normal older adults. In established clinical Parkinson's disease the rostrocaudal gradient becomes steep; the putamen is more damaged.
The Evaluation of “Spasticity”
Authors: Ashby P. , Mailis A. , Hunter J. 
Published: July 2016

ABSTRACT:Lesions of the upper motor neuron cause: 1. Alterations in segmental reflex activity. For example increased tendon jerks and velocity dependent stretch reflexes ("spasticity"), clonus, the clasp knife response, release of flexion reflexes and extensor plantar reflexes. 2. Impaired ability to activate motoneurons rapidly and selectively. Voluntary movements may also be restrained by co-contraction of antagonists muscles, by segmental reflexes (enhanced during voluntary effort) or by contractures. A combination of these factors may impair overall functional ability. Segmental reflexes, voluntary power and overall functional abilities can be assessed using clinical scoring systems. Recordings of muscle length, tension andEMG offer more objective measures of reflex and voluntary activity and of overall functions such as locomotion, and can separate weakness from co-contraction, spasticity from contracture. Methods are now available for exploring individual (transmitter specific) segmental reflex pathways and descending pathways in man. Lesions of the upper motor neuron are complicated by secondary changes in segmental neurons. Segmental reflex activity and muscle mechanics depend on the immediate past history of events. These factors must be taken into account.
Myoclonies du voile associées à une diminution de l’acide 5-hydroxy-indole-acétique céphalo-rachidien et répondant au clonazepam
Authors: Gauthier S. , Young S.N. , Baxter D.W. 
Published: July 2016

SUMMARYA patient presenting with palatal myoclonus was diagnosed as suffering from possible multiple sclerosis. A reduction of cerebrospinal 5-hydroxy-indole-acetic acid suggested a decreased central serotonergic turnover. A therapeutic trial with clonazepam, a serotonergic agonist, improved the myoclonus symptomatically. The possible involvement of serotonergic inhibitory systems in the expression of palatal myoclonus is discussed.
The Effect of Several Intertrial Intervals on the 1 Hz Interference Effect
Authors: Gaito John , Gaito Stephen T. 
Published: July 2016

SUMMARYExperiments were conducted to evaluate the effect of two intertrial intervals of 1-Hz brain stimulation on kindling behavior induced by 60-Hz sine wave stimulation. In two experiments, the effective threshold intensity (ETI) to elicit a convulsion was determined on four separate occasions with 5 days of daily trials between determinations. On each day experimental rats were stimulated with 1-Hz current on the first and third trials for 120 seconds duration and with 60-Hz current for 30 seconds on the second trial (1-60-1 group). A second group was stimulated with 60-Hz current on each trial (60-60-60 group). A third group received no stimulation on Trials 1 and 3 and 60-Hz current on Trial 2 (X-60-X group). In Experiment I, the intertrial interval was 3 hours; a 24 hour interval was used in Experiment 2. The results were similar in both experiments. For the 1-60-1 group, there was a steady increase in the intensity required to elicit a convulsion with 60-Hz current from ETI to ETI. However, the 24 hour interval produced a lesser effect than did the 3 hour interval (or the 1 hour interval used in previous experiments). Rats in the other groups maintained relatively stable values from ETI to ETI, with a slight decline occurring. Suppression of convulsive behaviour on daily trials was present with the 1-60-1 groups, and nonexistent with the other groups.
Multiple Regression Analysis of Diagnostic Predictors In Optic Nerve Disease
Authors: Kirkham T.H. , Coupland S.G. 
Published: July 2016

SUMMARYDemyelination is assumed to be the cause of the majority of cases of isolated optic neuritis. Because of the importance of establishing the presence of optic nerve dysfunction in patients suspected of having multiple sclerosis several new indices of optic nerve conduction have been reported including the visual evoked potential, the edge-light pupil cycle time, and the Pulfrich test. These measures purport to detect optic nerve dysfunction but with varying degrees of success. This study of 93 patients with clearly documented previous optic neuritis was conducted to determine the statistical relationship between these three measures and other clinical diagnostic indices for detection of previous optic nerve disease and the utility of the diagnostic predictors taken individually, and in combination. The other indices used were the presence of detectable optic atrophy, color vision defect and the presence of a relative afferent pupillary defect. The variables were submitted to linear stepwise multiple regression analysis which indicated that the presence of optic atrophy, defective color vision and prolonged pupil cycle time when used in combination provided the most useful diagnostic prediction of previous optic neuritis in this group of patients. The addition of visual evoked potentials, the Pulfrich test or presence of a relative afferent pupillary defect did not significantly increase predictive reliability.
Neurenteric Cysts of the Spinal Cord Mimicking Multiple Sclerosis
Authors: Vinters H.V. , Gilbert J.J. 
Published: July 2016

SUMMARY:A 54-year-old man died following a 20-year course of intermittent neurologic symptoms. He carried a diagnosis of multiple sclerosis, with most severe involvement thought to be in the spinal cord. At autopsy, two neurenteric (enterogenous) cysts were found to indent the anterior spinal cord — at the T4 and Tl I cord levels. Partial diplomyelia was present in the lumbosacral cord. These findings represent a unique combination of congenital abnormalities. Their embryogenesis and pathogenesis are discussed.