bluuebunny/crossref_metadata_2025 huggingface dataset:
Complex movement disorders induced by fluoxetine
Authors: Bharucha Kersi J. , Sethi Kapil D.
Published: December 2004

We report two cases of complex movement disorders induced by fluoxetine. A 72‐year‐old woman developed rhythmic palatal movements, myoclonus, chorea, and possibly dystonia after 2 years of therapy with fluoxetine. On withdrawal of fluoxetine, the movements abated after 5 days and did not recur. The second patient, a 58‐year‐old man, developed myoclonic jerking and rapid, stereotypic movements of his toes after a year of fluoxetine therapy. These complex movements have not been reported previously as an adverse effect of fluoxetine.
Improvement of severe postural cerebellar tremor in multiple sclerosis by chronic thalamic stimulation
Authors: Geny C. , Nguyen J.‐P. , Pollin B. , Feve A. , Ricolfi F. , Cesaro P. , Degos J.‐D.
Published: December 2004

Tremor can be particularly disabling in patients with multiple sclerosis (MS) and is mildly improved by drug treatment. The efficiency of stereotactic thalamotomy has been reported in a small number of patients but was counterbalanced by severe postoperative complications. Stimulation of the thalamic ventral intermediate nucleus, which is a less aggressive surgical method, is efficient in essential and in parkinsonian tremors. We report here the results of thalamic stimulation in 13 patients with MS with tremor. All patients were subjected to clinical examination, videorecording, and quantification of the functional disability before surgery and 3 months postoperatively. The surgical intervention was well tolerated in all cases. A clear improvement of the tremor was observed in 69.2% of the patients. Functional improvement was more varied and depended on the severity of tremor and coexistence of other neurological symptoms. Of the eight most severely affected patients, seven recovered the possibility to easily catch an object and use it. The results indicate that thalamic stimulation may be useful in the treatment of severe postural cerebellar tremor in MS.
Quantitative gait analysis in patients with vascular parkinsonism
Authors: Zijlmans J. C. M. , Poels P. J. E. , Duysens J. , van der Straaten J. , Thien T. , van't Hof M. A. , Thijssen H. O. M. , Horstink M. W. I. M.
Published: December 2004

Until now the clinical criteria for the diagnosis of vascular parkinsonism (VP) have been disputed. The purpose of the present study is to investigate whether quantitative gait analysis can differentiate between the gait pattern of patients with VP and the gait pattern of patients with idiopathic Parkinson's disease (PD). Twelve patients with VP, 12 patients with PD, and 10 neurologically nondiseased controls were examined by quantitative gait analysis. Patients with VP, having a similar gait velocity and stride length, showed relatively preserved arm swing with markedly more anteflexion in the shoulder on the forward sway of the arm swing than patients with PD. Patients with VP also showed less flexion dystonic posture of the elbow, hip, knee, and trunk than did patients with PD. There was no significant difference in the excursions and coordination of arm swing in the patients with VP compared with the control group. Both patient groups showed reduced leg movements, reduced hip extension, and reduced knee flexion and extension as compared with the controls.
Characteristics of individuals with Huntington disease in long‐term care
Authors: Nance M. A. , Sanders G.
Published: December 2004

This is a retrospective review of 97 Huntington disease (HD) patients living in long‐term care facilities in the Twin Cities. The purpose of the study was to describe the demographic features, patterns of behavior, weight change, nursing issues medication use, and hospitalization in this population. On admission to the nursing home, the “average” HD patient was of either sex, 45 years old, previously employed, a high school graduate, and not married. One third had severe behavior problems. Half gained and half lost weight; weight loss was not a predictor of death. Almost all used central nervous system‐active drugs, most commonly neuroleptics. Eighty‐four percent were ambulatory on admission, but 88% of those who died were nonambulatory at the time of death. We concluded that (a) HD patients are demographically different from other residents of long‐term care facilities, (b) weight gain can occur in some late‐stage patients, (c) negative behavior is a significant problem but is restricted to a subset of patients, and (d) adapting creatively to increasing multifaceted disability is the greatest challenge to the staff in facilities caring for HD patients.
A controlled trial of idebenone in Huntington's disease
Authors: Ranen Neal G. , Peyser Carol E. , Coyle Joseph T. , Bylsma Frederick W. , Sherr Meeia , Day Leslie , Folstein Marshal F. , Brandt Jason , Ross Christopher A. , Folstein Susan E.
Published: December 2004

One hundred patients with clinically diagnosed Huntington's disease (HD) were randomized to either idebenone, an antioxidant and enhancer of oxidative metabolism, or placebo, in a 1‐year, double‐blind, parallel‐group study aimed at slowing the rate of progression of the disease. Ninety‐one patients completed the study. There were no significant differences between groups on the primary outcome measures of the Huntington's Disease Activities of Daily Living Scale (ADL—an index of functional status) and the Quantified Neurologic Examination (QNE). Sample size calculations based on progression of the ADL and QNE in this study group revealed that a larger study group is necessary to detect any differences less than an almost complete halting of the disease. This argues for multicenter efforts for future therapeutic trials in HD.
Bilateral myoclonus of the trapezius muscles after distal lesion of an accessory nerve
Authors: Glocker Franz X. , Deuschl Günther , Volk Benedikt , Hasse Joachim , Lücking Carl H.
Published: December 2004

Observations of rhythmic or semirhythmic myoclonus due to a peripheral nerve lesion are exceptional. We report on a patient with thorax trauma with multiple bilateral hematomas of the paravertebral musculature. Eight years later he developed rhythmic myoclonus of both trapezius muscles and thoracic pain. Infiltration of a paramedially located scar at the level of D5–6 with a local anesthetic agent led to an intermittent relief of the myoclonus as did anesthetic blockade of the left accessory nerve. Surgical excision of the scar, which contained multiple dystrophic axons on histological examination, cured the patient's symptoms as illustrated in a videotape. This indicates that peripheral afferents contributed to the myoclonus. Ephaptic transmission, ectopic excitation, or misdirected neuronal sprouting secondary to the trauma are possible peripheral mechanisms responsible for the movement disorder. Successful blockade of the left accessory nerve with bilateral relief of the symptoms suggests a secondary, more centrally located mechanism, e.g., in the brain stem, probably driven by an altered afferent input. It is concluded that rhythmic or semirhythmic and focal myoclonus need a careful workup to look for a peripheral cause because such a condition would be accessible for surgical treatment.
A new sublingual formulation of apomorphine in the treatment of patients with Parkinson's disease
Authors: van Laar T. , Neef C. , Danhof M. , Roon K. I. , Roos R. A. C.
Published: December 2004

A new formulation of a sublingual tablet with 10 mg apomorphine was examined in 13 patients with Parkinson's disease. Vitamin C (250 mg) was added sublingually to lower the salivary pH. Four patients received sublingual apomorphine and nine received sublingual apomorphine as well as vitamin C. Subcutaneous apomorphine was given to all patients. The study was designed as a randomized three‐way cross‐over study. Tmax, Cmax, and bioavailability (F) were determined. Clinical efficacy was assessed by hand‐tapping during 30 s, walking time over 25 m, and a 4‐point tremor score. The mean Tmax after subcutaneous apomorphine was 14.5 ± 1.9 min with a mean Cmax of 19.2 ± 3.8 ng/ml. The mean clearance of all paients was 3.8 ± 0.6 L/min. The mean Tmax after sublingual apomorphine was 61.1 ± 6.9 min vs. 61.7 ± 8.2 min with vitmin C. The mean Cmax was 7.4 ± 1.0 ng/ml (– vitamin C) vs. 4.3 ± 1.3 ng/ml (+ vitamin C). These data resulted consequently in a not significantly different mean biovailability, varying from 17.6% (– vitamin C) to 6.1% ( + vitamin C). The latency of onset of clinical efficacy varied between 25.0 ± 8.5 min ( – vitamin C) and 26.0 ± 5.3 min ( + vitamin C). The duration of effect was lower (not significantly) when vitamin C was added: 88.0 ± 12.5 min ( – vitamin C) vs. 61.0 ± 11.9 min ( + vitamin C). These data show that 10 mg apomorphine sublingually was effective in 56% of the patients. The combination with vitamin C did not significantly change the latency of noset or duration of clinical efficacy. Sublingual apomorphine should be considered as an alternative in the treatment of “off” ‐periods in Parkinson's disease, in particular when patients have the capacity to anticipate their off‐periods.
Classical eyeblink conditioning in Parkinson's disease
Authors: Daum Irene , Schugens Markus M. , Breitenstein Caterina , Topka Helge , Spieker Sybille
Published: December 2004

Patients with Parkinson's disease (PD) show impairments of a range of motor learning tasks, including tracking or serial reaction time task learning. Our study investigated whether such deficits would also be seen on a simple type of motor learning, classic conditioning of the eyeblink response. Medicated and unmediated patients with PD showed intact unconditioned eyeblink responses and significant learning across acquisition; the learning rates did not differ from those of healthy control subjects. The overall frequency of conditioned responses was significantly higher in the medicated patients with PD relative to control subjects, and there was also some evidence of facilitation in the unmedicated patients with PD. Conditioning of electrodermal and electrocortical responses was comparable in all groups. The findings are discussed in terms of enhanced excitability of brainstem pathways in PD and of the involvement of different neuronal circuits in different types of motor learning.
Amyloid β‐peptide and the dementia of Parkinson's diease
Authors: Jendroska Klaus , Lees Andrew J. , Poewe Werner , Daniel Susan E.
Published: December 2004

It is not known whether an increased incidence of dementia in patients with Parkinson's disease (PD) is due to a higher incidence of Alzheimer's disease (AD) or to “early” Alzheimer‐type pathology. To determine whether amyloid β‐peptide (Aβ) of AD occurs more frequently in brains of patients with PD, we examined 50 cases and 79 controls by using histoblots for Aβ. Twentythree cases with PD had dementia, including all nine with Aβ distributed throughout the entire cerebral cortex; three of these cases had AD. In contrast, five of 17 controls with comparable Aβ accumulation were not demented. Neither AD nor Aβ deposition was increased in PD; furthermore, there was no statistical correlation between the amount of Aβ and the number of Lewy bodies in cerebral cortex. In 14 patients with PD in whom dementia was unrelated to Aβ, there was cerebral vascular disease (four), numerous cortical Lewy bodies (three), or hydrocephalus (two); in five further cases, dementia was not well explained by histopathologic changes. Our data found no increase of either AD or “early” Alzheimer‐type pathology in cases of PD; however, a synergistic effect between the two pathologies was suggested as contributing to dementia.
Focal task‐specific tremors
Authors: Soland Valerie L. , Bhatia Kailash P. , Volonte Maria A. , Marsden C. David
Published: December 2004

Focal task‐specific tremors besides primary writing tremor have rarely been reported in the literature. We describe inne cases of focal tremors induced by different specific tasks, involving a repetitive and frequently performed movement. Only one of these patients had a family history of any similar disorders. There was no overt dystonia in any of the cases, but these tremors may be forms of focal dystonia, rather than a manifestation of essential tremor.
Evidence of cortical metabolic dysfunction in early Huntington's disease by single‐photon‐emission computed tomography
Authors: Sax Daniel S. , Powsner Rachel , Kim Anthony , Tilak Shripad , Bhatia Rita , Cupples L. Adrienne , Myers Richard H.
Published: December 2004

We compared perfusion of prefrontal, motor, and sensory cortices and basal ganglia in 29 Huntington's disease (HD) patients and nine controls. We found a significant reduction in perfusion in patients with HD of short (<6 years, n=10), medium (6–10 years, n=8), and long duration (>10 years, n=11) compared with controls. Among short‐duration patients, we observed decreases in cortical perfusion before evidence of atrophy on magnetic resonance imaging, suggesting that decreases in neuronal activity, as reflected by perfusion levels, precede gross structural changes. As expected, decreased perfusion was marked in basal ganglia. The extent of cortical perfusion correlated with clinical assessments of functional capabilities as well as with the duration of disease. Perfrontal perfusion correlated with cognitive measures, and motor cortical perfusion correlated with physical disability and activities of daily living scores. We found no significant clinical correlations with sensory cortical perfusion. Single‐photon‐emission computed tomography may be a sensitive method for assessing disease progression in clinical trials and pharmacologic intervention.
Saccadic eye movements in idiopathic blepharospasm
Authors: Bollen E. , Van Exel E. , van der Velde E. A. , Buytels P. , Bastiaane J. , van Dijk J. G.
Published: December 2004

Visually guided saccades, memory‐contingent saccades, and antisaccades were studied with an infra‐red reflection technique in 12 patients with idiopathic blepharospasm and in controls. Latencies of the three kinds of saccades were prolonged. Peak velocities and gains did not differ. Our results indicate an initiation defect in the saccadic system, which may be localized in the caudate nucleus.
Abnormal sensorimotor integration in writer's cramp: Study of contingent negative variation
Authors: Ikeda Akio , Shibasaki Hiroshi , Kaji Ryuji , Terada Kiyohito , Nagamine Takashi , Honda Manabu , Hamano Toshiaki , Kimura Jun
Published: December 2004

To investigate the pathophysiology of idiopathic focal dystonia, we recorded contingent negative variation (CNV) as a physiological index of sensorimotor intergration in 14 right‐handed patients with writer's cramp and compared it with normative data. CNV was recorded in the S2 choice reaction time paradigm: Two kinds of auditory S2 (Go or No‐Go) were given 2 s after the auditory S1, and the subject reacted only to the Go signal by extending the wrist. In normal subjects, the late CNV amplitude had no difference at Cz between left‐and right‐hand tasks and was symmetric without significant amplitude laterality irrespective of the side of hand movement. In patients with writer's cramp, the late CNV amplitude at Cz was relatively larger for the left‐hand task than the right‐hand task (p<0.03), and a significant amplitude laterality of the late CNV (larger on the right) was present especially at the central area for the right‐hand task (p<0.03). Since the late CNV is known to be generated, at least inpart, from primary and supplementary motor cortices, the significant laterality of the late CNV seen with the right‐hand task in patients with writer's cramp might represent functional abnormality of motor cortices possibly as the result of basal ganglia function.
Blink reflex excitability is abnormal in patients with periodic leg movements in sleep
Authors: Briellmann Regula S. , Rösler Kai M. , Hess Christian W.
Published: December 2004

The excitability of the late component of the blink reflex was measured in 19 patients with periodic leg movements in sleep (PLMS) and in 18 control patients with other sleep complaints. PLMS patients were not different from controls regarding age, body mass index, and apneas and hypopneas per hour of sleep. The latencies of the R1 and R2 components of the blink reflex were not different between the groups. However, in PLMS, the excitability of the R2 response was markedly enhanced: The second R2 response to a pair of stimuli given at an interval of 500 ms was in PLMS 59.5% (range 21–87%) of the first R2 response and in controls 18.8% (range 2–79%) (p < 0.0001, Mann‐Whitney U test). These results provide further evidence of an altered motor control in PLMS, which is likely to be located subcortically and possibly related to the dopaminergic striaitopallidal system.
Brainstem encephalopathy with stimulus‐sensitive myoclonus leading to respiratory arrest, but with recovery: A description of two cases and review of the literature
Authors: Kullmann D. M. , Howard R. S. , Miller D. H. , Hirsh N. P. , Brown P. , Marsden C. D.
Published: December 2004

Two unrelated patients developed bulbar symptoms, followed within several weeks by spontaneous myoclonus and painful, generalized, stimulus‐sensitive jerks triggered by unexpected noises and cutaneous stimuli. They progressed to respiratory arrest and required mechanical ventilation, but both patients subsequently made an almost full recovery. These cases stress the importance of persevering with supportive treatment despite rapid progression of this severe generalized movement disorder. The relationship of brainstem reflex myoclonus to hyperekplexia, progressive encephalomyelities with rigidity, and the stiff‐man syndrome is discussed.
Effects of central dopaminergic stimulation by apomorphine on swallowing disorders in Parkinson's disease
Authors: Tison F. , Wiart L. , Guatterie M. , Fouillet N. , Lozano V. , Henry P. , Barat M.
Published: December 2004

Swallowing disorders are common in Parkinson's disease but are of obscure and complex nature and pathophysiology. The effect of central dopaminergic stimulation on disordered swallowing is not well known. We studied the effects of apomorphine (in combination with domperidone) on buccolinguofacial motoricity and on various swallowing stages by using videofluoroscopy in eight patients with dysphagia. Swallowing abnormalities more frequently encountered were vallecular stasis (n = 7), fragmentation of the bolus (n = 7), and buccal stagnation of the bolus. Apomorphine improved vallecular stasis and fragmentation in about half the cases and improved buccal stagnation in all cases. Direct laryngeal penetration was found in three cases and improved in two of them. The total swallowing duration was improved by apomorphine in a subset of patients (n = 5). This improvement correlated with an improvement of the buccolinguofacial motoricity and was combined with an improvement of pharyngeal transit time. Thus central dopaminergic stimulation by apomorphine improved swallowing in a subgroup of patients, mainly in its early stages.
Intrafamilial variability in Machado‐Joseph disease
Authors: Subramony S. H. , Currier R. D.
Published: December 2004

Dominantly inherited ataxias resulting from different gene mutations are difficult to distinguish based on clinical phenotypes. We believe the phenotypic variability within families can be a clue to clinical diagnosis. We illustrate the range of phenotypes extending from levodopa‐responsive extrapyramidal disease to more purely ataxic syndromes seen in two families with molecularly proven Machado‐Joseph disease.
N‐0923, A novel soluble dopamine D2 agonist in the treatment of parkinsonism
Authors: Calabrese Vincent P. , Alvin Lloyd K. , Brancazio Pasquale , Cefali Eugene , Martin Pauline , Wall James , Sica Dominic
Published: December 2004

N‐0923, a novel aminotetralin dopamine D2 agonist, was shown to effectively reverse parkinsonian symptoms in nine dopa/agonist‐responsive Parkinson's disease patients. The drug was given up to 4.5 hours by continuous intravenous (IV) infusion using an IV pump. The onset of anti‐parkinsonian effect was seen within minutes of the initiation of the infusion and was absent within 90 minutes of cessation of the infusion. The short elimination half‐life of N‐0923 (90 min) would allow for the rapid initiation of drug effect when necessary and at the same time permit the effect to be terminated quickly if necessary. The drug would be useful in situations where oral medication is not feasible or is associated with erratic absorption. The patients tolerated the drug well. Dose escalation load was limited by nausea and vomiting. It should be noted that the doses were increased until these symptoms occurred, but therapeutic effects were noted well before the side effects occurred. Using a modified Columbia scale, maximum improvement consisted of a 27–95% drop in score. Maximum response was obtained at infusion rates varying from 2–16 μg/kg per hour and at blood levels of 0.11–1.49 μg/mL.
Pallidotomy improves motor responses and widens the levodopa therapeutic window in Parkinson's disease
Authors: Skalabrin Elaine J. , Laws Edward R. , Bennett James P.
Published: December 2004

Stereotactic posteroventral pallidotomy (PVP) as a treatment for Parkinson's disease (PD) symptoms has been increasingly used in moderate‐advanced disease. We examined the pharmacodynamic responses of PD patients to single oral levodopa doses and intravenous levodopa infusions before and after PVP surgery. Nine subjects with advanced PD received a single oral dose and ramped intravenous levodopa infusions before and 3–5 weeks after unilateral PVP. Timed motor tasks, Unified Parkinson's Disease Rating Scale (UPDRS) evaluations, and ordinal dyskinesia rating were performed after oral levodopa and during IV levodopa infusions. Serum prolactin and dopa levels were measured during the levodopa infusions. Overall timed motor but not motor UPDRS scores were improved after PVP in both the worst (“off”) and best (“on”) states. Contralateral but not ipsilateral limb dyskinesias were substantially reduced at all serum (dopa) levels after PVP. Ipsilateral and contralateral timed motor performance at low serum (dopa) levels was improved by PVP. Walking speeds at all serum (dopa) levels were not changed by PVP. Serum prolactin was reduced equally by increasing (dopa) preoperatively and postoperatively. PVP significantly and favorably altered oral and intravenous levodopa pharmacodynamics by improving bilateral limb motor function and contralateral dyskinesia but did not alter walking speed. PVP appears to widen significantly the therapeutic window for levodopa in PD.
Dopamine D3 receptor is decreased and D2 receptor is elevated in the striatum of Parkinson's disease
Authors: Ryoo Han L. , Pierrotti Dylan , Joyce Jeffrey N.
Published: December 2004

The mesolimbic dopamine (DA) system preferentially innervates the D3 receptor, whereas the D2 receptor is, in addition, a target of the nigrostriatal DA system. In human brain D3 receptors and D3 mRNA‐expressing neurons are largely segregated to brain regions that are the targets of the mesolimbic DA system and the efferents of the “limbic striatum.” Thus, D3 receptors may regulate effects of DA on the “limbic” cortico‐striatal‐pallidal‐thalamic‐cortical loop. The nigrostriatal DA system is considerably more damaged in Parkinson's disease (PD) than the mesolimbic DA system. We report here, using radioligands selective for the D2 and D3 receptor, that these receptors are independently changed in PD. Tissue collected at autopsy from nine subjects with a diagnosis of PD and eight age‐matched subjects with no evidence of a neurologic disorder was processed for [125I]epidepride binding to D2 receptors, [125I] trans‐7‐OH‐PIPAT binding to D3 receptors, [125I]RTI‐55 for the DA transporter (DAT), and immunoautoradiography for tyrosine hydroxylase (TH) using autoradiographic methods. Dopaminergic innervation to the caudal putamen was profoundly reduced and to a lesser extent in the rostral putamen in PD. DAT sites but not TH protein levels were reduced in the nucleus accumbens (NAS) in PD compared with age‐matched control subjects. This is consistent with a loss of dopaminergic innervation from the mesolimbic DA system but elevation in TH production. D3 receptors were significantly reduced in PD by 40–45% particularly in the NAS and putamen. D2 receptors were elevated in PD in the dorsal putamen by 15%. The reduction in D3 receptor number was not observed in PD cases with a diagnosis of less than 10 years. The changes in DA D3 receptor number is interesting in light of the development of antiparkinsonian agents that are D3‐preferring agonists.
Amantadine reduces levodopa‐induced dyskinesias in parkinsonian monkeys
Authors: Blanchet Pierre J. , Konitsiotis Spyridon , Chase Thomas N.
Published: December 2004

The antidyskinetic potential of the glutamate NMDA receptor channel blocker amantadine was evaluated in four levodopa‐primed parkinsonian monkeys using two different regimens (1.25 or 2.5 mg/kg administered subcutaneously twice daily for 3–6 days). When administered with a relatively low dose of levodopa, amantadine produced a near‐total suppression of choreiform dyskinesias and a substantial reduction in dystonic dyskinesias at the expense of a significant reduction in antiparkinsonian response. With a high dose of levodopa, amantadine had a smaller but still significant effect on dyskinesias without altering the antiparkinsonian response. These results lend support to the view that glutamate receptormediated mechanisms contribute to levodopa‐induced dyskinesias. They also suggest that amantadine could alleviate such complications in parkinsonian patients, especially with careful dose optimization.
Clinical characteristics of essential tremor: Data from a community‐based study
Authors: Louis Elan D. , Ford Blair , Wendt Kristin J. , Cameron Gabriella
Published: December 2004

BACKGROUND: 99.5% of individuals with essential tremor (ET) who live in the community have mild tremor and do not attend clinics. Clinic‐based studies of ET have not allowed investigators to characterize the full clinical spectrum of this disorder. In community‐based studies of ET, the primary focus has been the prevalence rather than the clinical characteristics of ET.

OBJECTIVE: To describe the clinical characteristics of ET as seen in a community‐based study.

METHODS: 73 subjects with ET, identified in a community‐based study of ET in Washington Heights‐Inwood, New York, underwent a standardized 84‐item physicianadministered tremor interview and a 26‐item videotaped tremor examination which included 12 bedside tests for ET. Two neurologists who specialized in movement disorders and who demonstrated excellent interrater agreement rated the severity of tremor using a 0 to +3 clinical rating scale and assigned a total tremor score (range, 0–36) and a diagnosis of ET.

RESULTS: Diagnoses in the 73 cases were: definite ET (18, 24.7%), probable ET (32, 43.8%), and possible ET (23, 31.5%). The mean total tremor score was 17.8 of 36. Thirty‐six of 73 (49.3%) were asymptomatic, answering “no” to the question “do you often have shaking or tremor that you can't control?” Sixty‐seven of 73 (91.8%) had not been prescribed medication for tremor. On average, subjects received tremor ratings of ≥+2 on only 5.4 of the 12 bedside tests for ET. Kinetic tremor was rated as more severe than postural tremor in 72 (98.6%) of 73 cases.

CONCLUSIONS: We present the clinical findings of a group of largely untreated, unselected cases of ET that would not otherwise have come to neurologic attention. The tremor was mild, often asymptomatic, and not uniformly present throughout the examination. It was rarely treated. The kinetic component of the tremor was more severe than the postural component. These clinical data further our understanding of the clinical spectrum of ET.
Brain phospholipids and fatty acids in Friedreich's ataxia and spinocerebellar atrophy type‐1
Authors: Eder Klaus , Kish Stephen J. , Kirchgessner Manfred , Ross Brain M.
Published: December 2004

Previous studies of patients with spinocerebellar atrophy type 1 (SCA‐1) and Friedreich's ataxia (FA) have suggested the occurrence of membrane distrubances in both disorders. We measured concentrations of phosphatidylcholine (PC), diacyl and plasmalogen phosphatidylethanolamine (PE), and phosphatidylserine (PS), along with their fatty acid profiles, in the brains of eight patients with Friedreich's ataxia (FA) and nine patients with dominantly inherited spinocerebellar atrophy type 1 (SCA‐1). Compared with the controls, levels of all phospholipid types (PE, PS, and PC) were reduced in the cerebellar but not occipital cortex of SCA‐1 patients. In contrast, in the FA group, levels of PS and PE, but not PC, were reduced in both cerebellar and occipital cortices. The fatty acid composition of individual brain phospholipids was altered in both FA and SCA‐1 patients, most markedly in the plasmalogen PE and PS classes of cerebellar phospholipids. Given the neuropathologic characteristics of each disorder, it is likely that altered fatty acid composition and phospholipid levels in SCA‐1 cerebellar cortex occur as a consequence of pronounced cerebellar degeneration. In contrast, reduced phospholipid levels in FA cerebellar and occipital cortex, areas characterized by, at most, minimal neuronal loss in FA, may represent a widespread alteration in cellular phospholipid metabolism occurring in response to the specific gene defect in the disorder.
Adult head‐banging and stereotypic movement disorders
Authors: Mendez Mario F. , Mirea Adrian
Published: December 2004

Stereotypic movement disorders (SMD) such as head‐banging, which are common among children with mental retardation or pervasive developmental disorders, may also occur in intellectually normal adults. We report a 27‐year history of daily head‐banging with self‐injury in a 49‐year‐old man with normal cognition. The patient had no personal or family history of Tourette's syndrome, tic disorder, obsessivecompulsive disorder (OCD), or mental retardation. The frequency of his stereotypical head‐banging increased with anxiety, loud noises with startle, and boredom. He reported a sense of pleasure from his head‐banging, and the frequency of this behavior decreased when he was treated with the opioid antagonist naltrexone. Although not diagnostic, the selfstimulatory or pleasurable component of head‐banging, bodyrocking, thumb‐sucking, and other SMD may help distinguish them from tics, Tourette's syndrome, OCD, and deliberate selfharming behavior. This report reviews the disorders associated with SMD and discusses the potential mechanisms for these behaviors. The treatment of SMD includes drugs that work through opioid, serotonergic, or dopaminergic systems.
Effective treatment of orthostatic tremor with gabapentin
Authors: Evidente Virgilio Gerald H. , Adler Charles H. , Caviness John N. , Gwinn Katrina A.
Published: December 2004

We report seven patients with orthostatic tremor (OT) who were successfully treated with the anticonvulsant gabapentin. Five of the patients had been previously tried on clonazepam, the most commonly used drug for OT, four without any benefit. The degree of improvement perceived by the patients with gabapentin varied from 60–80% (mean 73%). The effective dose of gabapentin ranged from 300–1800 mg/day (mean 1030 mg/day). The side effects were generally mild, transient, and dose‐related. Duration of response has so far ranged from 2–22 months (mean 11 months) with all patients still currently benefiting from gabapentin. We conclude that gabapentin may be an effective treatment for OT. Further trials are indicated.
An akinetic‐rigid syndrome, depression, and stereotypies in a young man
Authors: Lance James W. , Hickie Ian , Wakefield Denis , Colebatch James G. , Cardoso Francisco , Vidailhet Marie
Published: December 2004

A young man is presented who developed an akinetic‐rigid syndrome shortly after a minor illness. Rituals and stereoptypies were prominent. At its most severe he was unable to feed himself. There was no response to L‐dopa/cardopa treatment. A course of ECT was followed by a marked improvement in his condition. Attempts to stop ECT for more than a week have led to recurrence of his bradykinesia.
A case of beheading dating from the celtic period (la Tène B, Sarliève‐Grande Halle, France)
Authors: Ardagna Y. , Richier A. , Vernet G. , Dutour O.
Published: December 2004

Excavation at the site of Sarliève‐Grande Halle, La Grande Halle revealed a large celtic necropolis dating from the 1st century BC. Burial number SP 2170 presented evidence of beheading. The position of the body showed a proper anatomical situation of the head in spite of a dislocation of C1–C2 and abnormal rotation of the head on the right side. Moreover, the arms were in an unusual position, with internal rotation of the humeri, the forearms crossed and the palm up position of left hand. The second cervical vertebra showed complete section of the odontoïd apophysis, associated with cutmarks on the vertebral body. The occipital bone had a large cut on the left side of the squama. These lesions correspond to those already described for decapitation in antiquity. The reconstruction of the chronology of the wounds as a form of execution is discussed in the historical context of the Celtic populations in Gaul. Copyright © 2004 John Wiley & Sons, Ltd.
Fracture behavior of polyetherimide (PEI) and interlaminar fracture of CF/PEI laminates at elevated temperatures
Authors: Kim Ki‐Young , Ye Lin , Yan Cheng
Published: December 2004

To investigate the effects of environmental temperature on fracture behavior of a polyetherimide (PEI) thermoplastic polymer and its carbon fiber (CF/PEI) composite, experimental and numerical studies were performed on compact tension (CT) and double cantilever beam (DCB) specimens under mode‐I loading. The numerical analyses were based on 2‐D large deformation finite element analyses (FEA). Elevated temperatures greatly released the crack tip triaxiality (constraint) and promoted matrix deformation due to low yield strength and enhanced ductility of the PEI matrix, which resulted in the greater plane‐strain fracture toughness of the bulk PEI polymer and the interlaminar fracture toughness of its composite during delamination propagation with increasing temperature. Furthermore, the high triaxiality was developed around the delamination front tip in the DCB specimen, which accounted for the poor translation of matrix toughness to the interlaminar fracture toughness by suppressing the matrix deformation and reducing the plastic energy dissipated in the plastic zone. Especially, at delamination initiation, the weakened fiber/matrix adhesion at elevated temperatures led to premature failure of fiber/matrix interface, suppressing matrix deformation and preventing the full utilization of matrix toughness. Consequently, low interlaminar fracture toughness was obtained at elevated temperatures. POLYM. COMPOS., 26:20–28, 2005. © 2004 Society of Plastics Engineers.
Relative viscosity models and their application to capillary flow data of highly filled hard‐metal carbide powder compounds
Authors: Honek Tomas , Hausnerova Berenika , Saha Petr
Published: December 2004

The rheological behavior of highly filled polymer systems used in powder injection molding (PIM) technology strongly influences the final properties of the products. In this study, the capillary flow data of multi‐component polymer binders—based on polyethylene, paraffin, ethylene‐based copolymers, and polyethylene glycol—compounded with three various hard‐metal carbide powders were employed. The rheology of such highly filled (up to 50 vol%) multiphase systems is necessarily a complex phenomenon characterized by strain dependent, non‐Newtonian properties complicated by flow instabilities and yield. Over 15 mathematical models proposed for highly filled systems were tested, some of them calculating the maximum filler loading. Due to the complex structure of the filler (irregular shape, particle size distribution) and a multi‐component character of the binder, the applicability of these models varied with the powder‐binder systems studied. However, the particular values of maximum loadings are in good accordance with the predictions based on powder characteristics. Simple modification of Frankel‐Acrivos model to the systems containing unimodal hard‐metal carbide powders with particles of an irregular shape and broad particle size distribution gave precise agreement between experimental data and model prediction. POLYM. COMPOS., 26:29–36, 2005. © 2004 Society of Plastics Engineers.
Special interaction between poly (propylene carbonate) and corn starch
Authors: Peng Shuwen , Wang Xiuyan , Dong Lisong
Published: December 2004

Poly (propylene carbonate) (PPC) has been blended with corn starch granule by melt mixing. The properties of blends were evaluated using differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMA), Instron tensile testing, and Fourier transform infrared (FTIR). FTIR indicates the presence of a specific interaction, hydrogen bonding, between the oxygen functional groups of PPC and the hydroxyl groups of starch. From DMA and DSC analysis, it is found that with the increase of starch content in PPC/starch blends, the glass transition temperature of PPC in blends increases a little due to hydrogen bonding. Tensile properties also proved that there is good interfacial adhesion in PPC filled with starch. POLYM. COMPOS., 26:37–41, 2005. © 2004 Society of Plastics Engineers.
A study of the polymerization of thermosetting polymers by electrical resistivity techniques
Authors: Warfield R. W. , Petree M. C.
Published: December 2004

A study was designed to show the nature of weathering of an elastomer poly( ester‐urethane), and to indicate methods of overcoining the deficiency. Unprotected polymer, when exposed to UV radiation in a Weatherometer, showed deterioration which is characterized by loss of tensile strength, some increase in modulus, and a decreased extensibility of surface skin.
Mechanisms of ultraviolet stabilization of plastics
Authors: Chaudet J. H. , Newland G. C. , Patton H. W. , Tamblyn J. W.
Published: December 2004

The effectiveness of ultraviolet stabilizers of various types of polyolefin, cellulose ester, and poly (vinyl chloride) plastics was investigated. Most of these stabilizers were of the ultraviolet‐absorbing type but two were of the nonabsorbing type. Exposures were made both outdoors and indoors in a Twin‐Arc Weatherometer. The latter was modified by the addition of ten 20‐watt fluorescent sun lamps to remedy the short‐ultraviolet deficiency of the enclosed carbon arcs.
A study of the weathering of an elastomeric polyurethane
Authors: Schollenberger C. S. , Dinbergs K.
Published: December 2004

A study was designed to show the nature of weathering of an elastomer poly(ester‐urethane), and to indicate methods of overcoming the deficiency. Unprotected polymer, when exposed to UV radiation in a Weatherometer, showed deterioration which is characterized by loss of tensile strength, some increase in modulus, and a decreased extensibility of surface skin.
Hydroxy alkyl phosphate esters as curing agents for epoxy resins
Authors: Cyr Marjorie C. St.
Published: December 2004

A new curing system which yields room temperature curing epoxy adhesives with high bond strength and softening point has been developed for service in contact with high explosives. Bisphenol A type resins cured with hydroxyl alkyl phosphate acid esters are used. Short pot life and relatively low alkali resistance are drawbacks of the system.
Some functions of 2‐hydroxybenzophenones as weathering stabilizers for polymers
Authors: Chaudet J. H. , Tamblyn J. W.
Published: December 2004

Derivatives of 2‐hydroxybenzophenone are well‐known stabilizers for such polymers as cellulose acetate butyrate and polyesters. Their stabilization effectiveness is commonly associated with their ability to screen a polymer from the harmful ultraviolet radiation found in sunlight. They also satisfy other requirements for effective stabilizers, namely, compatibility with many polymers and an inherent stability to ultraviolet light. Several other functions of 2 hydroxybenzophenones in stabilizing a polymer to ultraviolet light have been postulated, but little experimental data related to them are available. This paper deals with some of the additional functions of 2‐hydroxybenzophenones in weathering stabilization as investigated by nuclear magnetic resonance spectroscopy (NMR) and electron paramagnetic resonance spectroscopy (EPR).
A method for determination of maximum heat resistance of plastics
Authors: Kanavetz I. F. , Batalov L. G.
Published: December 2004

A new method for measuring heat stability and temperature of degradation of thermosetting plastics is described, as well as an improved method for the determination of transition temperature into glassy or viscous state for thermosetting resins. Magnitude of elastic deformation is tied in with length of polymer chain and lattice density.
Dielectric properties of plasticized melamine resins
Authors: Schneider W. C.
Published: December 2004

During the last thrity years, dielectric measurements have been employed extensively to provide a better understanding of the interactions between polymer and plasticizer in various thermoplastic formulations. Recently, a series of melamine resins, plasticized to the extent that shrinkage and internal stress were modified, became available. Since there is little information in the literature concerning the dielectric properties of such thermosetting resins, a study was made of the variation of dielectric constant and loss as a function of frequency and temperature.
Cryogenic adhesive properties of bisphenol‐A epoxy resins
Authors: Hiza M. J. , Barrick P. L.
Published: December 2004

This article includes a comparison of the adhesive properties of bisphenol‐A expoxides at 300°K and 76°K with respect to the molecular weight of the uncured resins. Joints of 2024 aluminum were tested at 300°K and 76°K in tensile‐shear and in impact‐shear, and total linear thermal contraction of the cured resins was measured between the two temperatures. Results are discussed with respect to residual joint stresses and adsorptive properties of the resins.
Electrical resistivity of polymers
Authors: Warfield R. W. , Petree M. C.
Published: December 2004

The magnitude and temperature dependence of the electrical resistivities of a number of thermoplastic and thermosetting high polymers have been determined. Activation energies for the electrical conduction process Ee have been calculated and found to vary from 12 to 60 Kcal/mole depending upon the structure of the polymer. Results are interpreted in terms of an ionic diffusion process and discussed in terms of the structure of the polymers.
Polyethylene flow data from melt viscometer and commercial extruder measurements
Authors: Schreiber H. P.
Published: December 2004

For broad ranges of operating conditions and a wide variety of high pressure polyethylenes, the flow data obtained from a high shear viscometer and a commercial extruder are identical. Discrepancies between flow data can result from non steady state viscosities in the high shear viscometer, or from cooled screw extruder operation. In the broad regions in which the flow data concur, the readily obtained viscometer data are suitable for predictions of extruder performance. The principle is illustrated by the good correlation of a viscometer flow curve parameter and the screw power consumption in the extruder. Principles outlined for flow data identity and extruder performance prediction are believed to be general, but the quantitative limits defined are specific to the extrusion devices involved.
An investigation of some variables affecting impact resistant thermoplastics
Authors: Bobalek Edward G. , Evans Robert M.
Published: December 2004

Recent technology has evolved a number of dissimilar thermoplastics which under conditions of ambient temperature and impact loading show both the high modulus, which is mainly a property of brittle polymers in the glassy state, and also the impact resistance, such as may be expected of polymers in the rubbery state. Several of these special plastics were examined by electronmicroscopy and also with respect to several aspects of their mechanical behavior to establish by direct observation and inference whether or not different types of plastics exhibit some common features of structure which promote impact resistance. These observations suggest the hypothesis that special circumstances of domain heterogeneity can override many other variables of composition or molecular structures in controlling the fracture mechanism.
Thermodynamic diagrams for polyethylene resins
Authors: Lupton J. M.
Published: December 2004

For resins of room temperature density 0.91 to 0.96 g/cc, enthaply and internal energy diagrams have been developed from 0 to 200°C and up to 1000 atmospheres. These diagrams can be used for estimating properties for which data are not available, and provide unified view of many properties of polyethylene under conditions of fabrication and use. Extent of crystallinity estimates can be made from enthalpy, internal energy, specific volume, compressibility and melting point data provided for hypothetical amorphous, crystalline and actual resins.
The strength of glassy polymers
Authors: Berry J. P.
Published: December 2004

The Griffith theory for brittle fracture predicts that the tensile strength should be inversely proportional to the square root of the size of a defect or flaw in the sample tested. The validity of this relation has been investigated for the glassy polymers, poly(methyl methacrylate) and polystrene. The results indicate that the strength of the polymers depends on two factors: (1) the surface energy, and (2) the inherent flaw size. The surface energy is primarily that dissipated in a viscous flow process and the inherent flaw size is related to the tendency of the polymer to craze under stress.
Flow patterns in a non‐Newtonian fluid in a single‐screw extruder
Authors: Mohr W. D. , Clapp J. B. , Starr F. C.
Published: December 2004

Flow patterns in the channel of a screw extruder have been investigated in a study utilizing a model extruder with stationary screw and a rotating, transparent barrel. Photographs of flow streamlines at conditions over the full range of output restriction are presented for a non‐Newtonian fluid. A technique employing photographs of particle tracers was used with the same apparatus to permit quantitative measurement of velocity profiles with both a Newtonian and a non‐Newtonian fluid.
Effect of gamma radiation on chemical structure of plastics
Authors: Krasnansky V. J. , Achhammer B. G. , Parker M. S.
Published: December 2004

Twelve plastics representing various chemical structures were studied as part of a program to determine the utility of plastics as packaging materials in the high radiation presentation of food. The plastics were exposed to selected dosages of Cobalt‐60 gamma radiation in vacuum and in air. Gas evolution and changes in infrared spectra as a result of irradiation were used to hypothesize the relative stability of these plastics to irradiation. Based on these facts it was found that plastics containing conjugated ring systems, ionic linkages, and chlorine in side groups were the most stable.
Resins from cyclohexene oxide derivatives and fatty acids
Authors: McGary C. W. , Patrick C. T.
Published: December 2004

This article describes preparation of resins as described in the title above, and the effect of concentration of the diepoxide, dimer acid, and initiator (stannous octoate). Proportion of dimer acid and diepoxide has a marked influence on hardness and tensile properties of resins. Change in tensile properties upon aging correlates very well with change in hardness. Higher proportions of dimer acid produce softer, more flexible resins. The resins have unique electrical properties at temperature up to 175°C, apparently because of the high proportion of hydrocarbon in the resin.