bluuebunny/crossref_metadata_2025_split huggingface dataset:
Amyotrophic lateral sclerosis and parkinsonism‐dementia among Filipino migrants to Guam
Authors: Garruto Ralph M. , Gajdusek D. Carleton , Chen Kwang‐Ming 
Published: January 2005

AbstractAmyotrophic lateral sclerosis (ALS) has occurred in 9 Filipino migrants to Guam 1 to 29 years after their arrival and parkinsonism‐dementia (PD) in 2 migrants 13 and 26 years after arrival. Seven additional Filipino patients developed more classic Parkinson disease (P) 5 to 24 years after their migration to Guam. Furthermore, 10 part‐Filipino patients who were born on Guam of Filipino and Chamorro parentage developed ALS, while 6 such part‐Filipino patients developed PD. An estimate of the average annual crude mortality rate for ALS among Filipino migrants was approximately six times that of the continental United States, yet half that currently observed among Chamorros living on Guam. A majority of all migrant patients were born in northwestern Luzon in the Philippine Islands, indicating the desirability of an intensive field epidemiological investigation in that area.
Monoaminergic mechanisms and experimental cataplexy
Authors: Foutz Arthur S. , Delashaw John B. , Guilleminault Christian , Dement William C. 
Published: January 2005

AbstractThe effects of pharmacological alteration of the monoamine systems were investigated in a canine model of narcolepsy. Cataplexy was quantified in eight severely affected dogs by means of the food‐elicited cataplexy test. The specific norepinephrine (NE) uptake blocker nisoxetine, and (to a much lesser extent) the specific serotonin (5‐HT) uptake blocker fluoxetine, significantly suppressed cataplexy, as did the tricy'lic antidepressants protriptyline, amitriptyline, and chlorimipramine. Thus, experimental cataplexy is suppressed more by inhibition of the uptake of NE than of 5‐HT. Methylphenidate, the α‐adrenoreceptor blocker clonidine, and the dopamine receptor blocker pimozide also suppressed cataplexy in dogs. The β‐adrenergic blocker propranolol, the fatty acid γ‐hydroxybutyrate, and the monoamine oxidase inhibitors clorgyline and pargyline had little or no effect. With one exception (pimozide). all the drugs that suppressed cataplexy are known to be potent suppressors of REM sleep. The suppression of cataplexy induced by nisoxetine or protriptyline was reversed by the anticholinesterase physostigmine, further supporting a postulated aminergic‐cholinergic interaction in the mechanisms for cataplexy.
Regional activities of metabolic enzymes and glutamate decarboxylase in human brain
Authors: Maker Howard S. , Weiss Cipora , Weissbarth Sulamith , Silides Demetra J. , Whetsell William 
Published: January 2005

AbstractInterpretation of biochemical measurements in the human brain after death is complicated by a variety of premortem, perimortem, and postmortem factors. The activity of glutamic acid decarboxylase (GAD) in particular has been found to vary considerably among human brains. In contrast to neurotransmitter‐associated enzymes, metabolic enzymes are present in all brain cells and should not be specifically lost by patterned neuronal cell loss such as that which occurs in Parkinson disease. We compared the activity of GAD to that of the metabolic enzymes creatine kinase (CK), adenylate kinase, hexokinase, β‐glucuronidase, and malate, lactate, glucose‐6‐phosphate, and isocitrate dehydrogenases in 24 regions of six human brains. Of the metabolic enzymes, only CK showed a 5‐fold variation approaching that of GAD. Like GAD, CK activity was stable postmortem, but its activity was apparently inversely related to the severity and duration of the preterminal illness. CK may be a useful marker of agonal deterioration.
Virus‐induced electrotonic coupling: Hypothesis on the mechanism of periodic EEG discharges in Creutzfeldt‐Jakob disease
Authors: Traub Roger D. , Pedley Timothy A. 
Published: January 2005

AbstractExperimental evidence and computer modeling indicate that periodic synchronous cellular depolarizing bursts (interictal spikes) arise when the balance between recurrent inhibition and local excitatory coupling is altered. Such a mechanism may explain the generalized periodic sharp waves that characterize the electroencephalogram of many patients with Creutzfeldt‐Jakob disease. In Creutzfeldt‐Jakob disease, fusions of neuronal processes, particularly dendrites, may lead to abnormal electrotonic coupling between cells, providing the basis for powerful excitatory interaction whereby large neuronal aggregates burst in near synchrony. Cortical synchronous discharges would give rise to sharp waves in the electroencephalogram, whereas similar discharges in brainstem, spinal cord, or elsewhere could lead to myoclonic jerks.
Humoral immunity in myasthenia gravis: Biochemical characterization of acquired antireceptor antibodies and clinical correlations
Authors: Tindall Richard S. A. 
Published: January 2005

AbstractThe titer and characteristics of antiacetylcholine receptor antibody (A ChR‐Ab) were investigated in 184 patients with myasthenia gravis. Mean A ChR‐Ab titers of each clinical grade increased with the severity of the disease. A ChR‐Ab was always of an IgG class. IgM (5 of 92) and IgA (2 of 48) class AChR‐Ab were detected, but only concurrently with IgG and in low concentrations. IgG subclass 3 was not prominent. In 3 patients with A ChR‐Ab titers in the normal range, blockade of bungarotoxin binding to receptor could still be demonstrated. A ChR‐Ab from 6 patients was heterogeneous in affinity for receptor, reactivity with receptor from human ocular and gastrocnemius muscle, and blockade of toxin binding. A ChR‐Ab was oligoclonal in 4 of 6 patients, as shown by concurrent production of A ChR‐Ab IgG of both κ and λ types. Amniotic fluid and fetal cord serum did not interfere with antibody‐receptor interaction. Variation in the pattern of weakness among patients was a function of both the heterogeneity of A ChR antibodies and the antigenic uniqueness of receptor complexes from different human muscles.
The origin of spontaneous electrical activity at the end‐plate zone
Authors: Brown William F. , Varkey George P. 
Published: January 2005

AbstractTwo types of spontaneous electrical activity are present at the end‐plate zone: low‐voltage negative potentials that correspond to miniature end‐plate potentials, and larger voltage negative‐positive potentials. The electrogenic origin of the latter has been uncertain. The origin of these larger potentials was investigated in the rat phrenic nerve diaphragm preparation and in human gastrocnemius muscle just prior to intubation during administration of preoperative anesthesia. In the hemidiaphragm the larger voltage negative‐positive potentials, were rarely triggered by intracellular or tungsten microelectrodes. The negative‐positive potentials, however, were clearly triggered by contact of the concentric needle electrode with muscle hemidiaphragm at the end‐plate region. The potentials were abolished by curare. Likewise, the equivalent potentials observed at the human gastrocnemius end‐plate zone were blocked by neuromuscular blocking agents. Therefore, these positive‐negative discharges represent postsynaptic muscle fiber action potentials and not nerve fiber activity. They were probably presynaptically activated by mechanical irritation of the motor axon terminal and preterminal branches.
Congenital hypomyelination neuropathy: Glial bundles in cranial and spinal nerve roots
Authors: Towfighi Javad 
Published: January 2005

AbstractAutopsy examination of a 31/4‐year‐old child with a severe congenital hypomyelination neuropathy showed the anterior spinal nerve roots and motor cranial nerves to be almost devoid of myelin in their subarachnoid course. The posterior spinal nerve roots and peripheral nerves were less severely affected. Onion bulb formation was minimal and was present only in the sural nerve. There was extensive glial overgrowth in cranial nerves and spinal nerve roots adjacent to the brainstem and spinal cord. The extent and severity of glial overgrowth were similar to that described in Werdnig‐Hoffmann disease and morphologically appeared as glial bundles. These glial bundles are most likely secondary to chronic myelin and axonal damage.
Juvenile spinal muscular atrophy: A new hexosaminidase deficiency phenotype
Authors: Johnson William G. , Wigger H. Joachim , Karp Herbert R. , Glaubiger Lawrence M. , Rowland Lewis P. 
Published: January 2005

AbstractA 24‐year‐old Ashkenazi Jewish man was evaluated for a nine‐year history of progressive leg weakness with fasciculations. Electromyography, nerve conduction velocities, muscle biopsy, and serum creatine kinase were consistent with anterior horn cell disease. On rectal biopsy, ganglion cells were filled with membranous cytoplasmic bodies and an unusual submucosal layer of periodic acid‐Schiff positive histiocytes filled with granules was seen. Hexosaminidase A in serum and leukocytes was severely decreased in the patient and partially decreased in the parents and a brother. A paternal relative had classic infantile Tay‐Sachs disease.Juvenile spinal muscular atrophy in this patient, closely resembling the Kugelberg‐Welander phenotype, resulted from an α‐locus hexosaminidase deficiency disorder, possibly a genetic compound of HEXα2 and a milder hexosaminidase α‐locus allele. Other cases of hexosaminidase deficiency have included anterior horn cell disease as part of a more complex disorder, but this is the first case, to our knowledge, of a hexosaminidase deficiency disorder presenting as spinal muscular atrophy.
Interaction of myasthenic immunoglobulins and cholinergic agonists on acetylcholine receptors of rat myotubes
Authors: Ashizawa Tetsuo , Elias Stanton B. , Appel Stanley H. 
Published: January 2005

AbstractAcetylcholine receptor (AChR) antibodies from patients with myasthenia gravis (MG) impair neuromuscular transmission by altering the number of AChRs at the skeletal muscle motor endplate. Cholinergic agonists similarly impair transmission by altering the number and affinity of AChRs. The frequent clinical resistance to anticholinesterase medication in patients with MG has raised the question of possible synergistic effects of these agents on regulation of AChRs and neuromuscular transmission. To investigate this question, rat myotube cultures were incubated with MG globulin and carbamylcholine (CMC) for 20 hours. The number of AChRs was assayed by 125I‐α‐bungarotoxin binding. Incubation of cultures with both MG globulins and CMC consistently produced greater reductions of AChRs than incubation with either substance alone. Cholinergic antagonists blocked the CMC effect but not the MG globulin effect. A muscarinic antagonist had no effect. The effects of short‐term incubation with these substances on the affinity of AChR were assessed by the rate of 125I‐α‐bungarotoxin‐AChR complex formation. CMC desensitized AChRs, but MG globulins did not alter the affinity of AChRs. Results with this in vitro model suggest that chronic anticholinesterase therapy in the presence of MG AChR antibodies may aggravate failure of neuromuscular transmission in MG.
Nerve stimulation test in murine experimental autoimmune myasthenia gravis
Authors: Pachner Andrew R. , Kantor Fred S. 
Published: January 2005

AbstractUse of the mouse model of myasthenia gravis (murine EAMG), ideally suited for immunological study, has been hampered by the relatively mild character of the disease and by the extended time and effort required for inducing severe disease. Electromyographic measurement of the compound action potential after repetitive stimuli, the nerve stimulation test, was evaluated for its ability to diagnose neuromuscular transmission defects in mice immunized with Torpedo acetylcholine receptor. With the combination of provocative maneuvers and raising of the body temperature, EAMG could be diagnosed in nearly all immunized animals a few weeks after immunization, whereas clinical evaluation of muscle weakness was positive in less than half of immunized mice months after the first immunization. Thus, EMG provides a means of objective evaluation of the disease and attempts at its experimental modification.
In vivo demyelinating activity of sera from patients with Guillain‐Barré syndrome
Authors: Saida Takahiko , Saida Kyoko , Lisak Robert P. , Brown Mark J. , Silberberg Donald H. , Asbury Arthur K. 
Published: January 2005

AbstractThe in vivo demyelinating capacity of sera from 27 patients with Guillain‐Barré syndrome (GBS) and 47 other individuals was studied by intraneural injection into rat sciatic nerves. The morphological features of the nerves in cross section taken just proximal to the site of needle insertion was assessed 48 hours after injection and the extent of demyelination was quantitated. All 27 GBS serum samples were obtained in the first three weeks of clinical disease. Of these, 11 (41%) produced demyelination. Demyelinative activity of GBS sera correlated only with severity of clinical disease (p<0.01). The extent of demyelination after intraneural injection of human sera was less intense on average than that produced by sera from animals with experimental allergic neuritis. Three of 40 (7.5%) sera obtained from normal subjects and patients with other neurological diseases also caused in vivo demyelination, although the activity was weaker and occurred less often than with GBS serum.
Low CSF GABA in parkinsonian patients who respond poorly to therapy or suffer from the “on‐off” phenomenon
Authors: Teychenné Paul F. , Ziegler Michael G. , Lake C. Raymond , Enna S. J. 
Published: January 2005

AbstractThe γ‐aminobutyric acid concentration in cerebrospinal fluid was measured by radioreceptor assay in 23 parkinsonian patients (“good responders” and “poor responders” to drug therapy, “on‐off” state) and 11 age‐matched control subjects. Mean concentrations were similar but significantly lower in the poor responders and the “on‐off” state than in the good responders and control subjects. Patients who show good response to drug therapy appear to have a normal level of GABAergic activity that is not altered by drug therapy.
Selective fiber vulnerability in acute ischemic neuropathy
Authors: Parry Gareth J. , Brown Mark J. 
Published: January 2005

AbstractTo study the relationship between fiber size and vulnerability to ischemia, we produced partial infarction of the proximal posterior tibial nerve of Wistar rats by injecting arachidonic acid into the ipsilateral femoral artery. In the resulting lesion degenerating fibers were concentrated in the center of the nerve. Distal to the infarct, surviving myelinated and unmyelinated fibers were evenly distributed throughout both fascicles. Smaller myelinated fibers (<6μm in diameter) were more severely depleted than larger ones (>6μm). Unmyelinated fibers were reduced in number in proportion to or to a greater extent than myelinated fibers. These findings demonstrate that large myelinated fibers are relatively less vulnerable to peripheral nerve ischemia than smaller fibers, and do not support the contention that unmyelinated fibers are inherently resistant to acute ischemia.
Rapid improvement of myasthenia gravis after plasma exchange
Authors: Nielsen Viggo Kamp , Paulson Olaf B. , Rosenkvist Jørgen , Holsøe Eva , Lefvert Ann Kari 
Published: January 2005

AbstractNeuromuscular transmission and the staircase phenomenon in the adductor pollicis muscle were studied in six patients with myasthenia gravis before and 24 hours after single plasma exchanges given in short series over one to four weeks. An improvement in neuromuscular transmission was observed in all patients but one within 24 hours, suggesting that an immunological block of receptor sites is reversible or that acetylcholine receptors are rapidly resynthesized. In addition to a neuromuscular transmission defect, two of the patients also showed evidence of impaired excitation‐contraction coupling with a negative staircase phenomenon and reduced posttetanic twitch potentiation. This condition became normal after plasma exchange, which may indicate that a reversible immunological impairment of the sarcoplasmic reticulum was present. Improvement lasted up to several months. The anti‐acetylocholine receptor antibody titers were lowered in response to single plasma exchanges, but actual titer levels showed poor correlation with clinical and electrophysiological changes.
Monoclonal antibody analysis of blood T‐cell subsets in myasthenia gravis
Authors: Skolinik Paul R. , Lisak Robert P. , Zweiman Burton 
Published: January 2005

AbstractAnalysis of peripheral blood T‐cell subsets and B‐cells in patients with myasthenia gravis was performed using monoclonal antibodies and antibody against surface immunoglobulins (SIg) in an immunofluorescent technique. We found a modest but significant decrease in percentages of OKT3‐ and OKT8‐positive cells (thought to represent total T‐cells and T‐suppressor/cytotoxic cells, respectively) in myasthenics as a group. The percentage of OKT3‐positive cells was significantly decreased in patients with late‐onset disease (>35 years old), while the percentage of OKT8‐positive cells was significantly reduced in those with early‐onset myasthenia (<35 years old). Both thymectomized and nonthymectomized patients exhibited a decreased percentages of SIg‐positive cells in myasthenics and controls. Our results suggest that only modest imbalances of circulating immunoregulatory lymphocytes occur in myasthenia gravis; however, it is conceivable that the small differences observed in this study may reflect pathogenetically important reductions in a functionally distinct lymphocyte subpopulation.
Influence of azathioprine (Imuran) on in vitro immune function in multiple sclerosis
Authors: Oger Joel J.‐F. , Antel Jack P. , Kuo Han Hwa , Arnason Barry G. W. 
Published: January 2005

AbstractIn vitro immune function was assessed in patients with multiple sclerosis (MS) who were receiving Imuran therapy, in untreated MS patients, and in controls. In untreated stable MS patients, concanavalin A (Con A)‐driven mitogenic reactivity (T effector function) and Con A‐induced suppressor activity were modestly reduced compared to controls; pokeweed mitogen‐induced immunoglobulin G (IgG) secretion was increased. Untreated patients with active MS demonstrated high levels of IgG secretion and marked decreases in suppressor activity. In Imuran‐treated patients, Con A mitogenic responses and suppressor activity were comparable to those observed in untreated stable patients, and IgG secretion was reduced. The results in the treated patients likely reflect a direct effect of Imuran on B cell function rather than an indirect effect mediated via suppressor cells.
Cerebrospinal fluid acid‐base balance in newborns
Authors: Hermansen Marcus C. , Ellison Patricia H. 
Published: January 2005

AbstractIn adults, cerebrospinal fluid (CSF) acid‐base balance is an important determinant of cerebral blood flow, ventilatory drive, and state of consciousness. Sixteen lumbar punctures were performed on newborns (mean gestational age, 33.8 weeks; range, 26 to 44 weeks). The mean CSF pH was 7.366 units, 0.036 less than the mean capillary blood pH (NS). The mean CSF arterial carbon dioxide tension (Pco2) was 40.3 mm Hg, 6.7 greater than the mean blood Pco2 (p < 0.01). The mean bicarbonate ion concentration in CSF was 21.8 mEq/L, 1.2 greater than that in blood (NS). Acid‐base determinations in CSF of neonates with intraventricular hemorrhage did not differ significantly from those of neonates with otherwise normal CSF. These acid‐base values are similar to those found in adults and did not vary with gestational age, suggesting that mechanisms to establish this acid‐base gradient are developed by 26 weeks' gestation.
Measurement of the scrapie agent using an incubation time interval assay
Authors: Prusiner Stanley B. , Cochran S. Patricia , Groth Darlene F. , Downey Deborah E. , Bowman Karen A. , Martinez Hugo M. 
Published: January 2005

AbstractThe titer of the scrapie agent was determined by measurements of time intervals from inoculation to onset of illness and from inoculation to death. Both intervals were found to be inversely proportional to the size of the dose injected intracerebrally into random‐bred weanling Syrian hamsters. The logarithms of the time intervals minus a time factor were linear functions of the logarithm of the inoculum size. The time factors were determined by regression analysis in order to maximize these linear relationships. An equation relating the titer of the inoculum to the dilution of the sample and the length of the time intervals was developed. This equation facilitates the use of a computerized data base. Validation of these relationships was provided by comparing samples for which the agent was measured both by end‐point titration and by time interval assay. Agreement between the two methods was generally within ±0.5 log10 median infective dose units. No differences between the molecular properties of the agents from hamster and murine sources were observed using primarily the incubation time interval method with the former and end‐point titration with the latter. The advantages of this new approach based on time interval measurements are considerable with respect to time and resources.
The electroencephalogram in Tourette syndrome
Authors: Bergen Donna , Tanner Caroline M. , Wilson Robert 
Published: January 2005

AbstractThe electroencephalogram (EEG) was studied in 38 patients with Tourette syndrome. Psychometric tests and neurological evaluation identified patients with signs of additional central nervous system dysfunction. Thirteen patients (34%) had some EEG abnormality. In contrast to findings by other investigators, epileptiform activity was uncommon (only 2 out of 38). Most of the patients with EEG abnormalities either had other objective signs of neurological dysfunction or were taking haloperidol, a drug known to disturb the EEG.
A benign motor neuron disorder: Delayed cramps and fasciculation after poliomyelitis or myelitis
Authors: Fetell Michael R. , Smallberg Gerald , Lewis Linda D. , Lovelace Robert E. , Hays Arthur P. , Rowland Lewis P. 
Published: January 2005

AbstractTwo patients had a delayed syndrome of benign fasciulation after complete recovery from paralytic poliomyelitis and a third had the syndrome after an attack of purely motor myelitis. Myalgia was prominent in all three, and two had frequent cramps. Denervation hypertrophy occurred in two. The patients were observed for at least three years, and no new weakness was seen. These cases suggest that some chronic diseases of motor neurons may be benign.
Cognition in Parkinson disease: An event‐related potential perspective
Authors: Hansch Edward C. , Syndulko Karl , Cohen Stanley N. , Goldberg Zev I. , Potvin Alfred R. , Tourtellotte Wallace W. 
Published: January 2005

AbstractAuditory event‐related potentials (ERP) elicited in a target detection stimulus paradigm and pattern‐shift visual ERPs were studied in 20 male patients with idiopathic Parkinson disease (PD) and 20 age‐matched normal controls. Patients showed significantly increased latencies for both the P200 and P300 components of the auditory ERP. Patients and controls showed no significant differences in latency of the visual ERP but patients showed significantly decreased amplitude. Only one of five neuropsychological measures, the Symbol Digit Modalities test (SDMT), showed a significant negative correlation with P300 latency. The significant association between the two measures that showed impairments in the PD patients (P300 latency and SDMT scores) suggested that these measures reflect a common, disrupted aspect of cognitive function in PD.