Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Harald Hefter is active.

Publication


Featured researches published by Harald Hefter.


Neurology | 1998

Human anterior intraparietal area subserves prehension: a combined lesion and functional MRI activation study.

Ferdinand Binkofski; C. Dohle; Stefan Posse; K. M. Stephan; Harald Hefter; R. J. Seitz; Hans-Joachim Freund

It has been shown in nonhuman primates that the posterior parietal cortex is involved in coordination of arm and eye movements in space, whereas the anterior intraparietal area in the anterior lateral bank of the intraparietal sulcus plays a crucial role in fine finger movements, such as grasping. In this study we show by optoelectronic movement recordings that patients with cortical lesions involving the anterior lateral bank of the intraparietal sulcus have selective deficits in the coordination of finger movements required for object grasping, whereas reaching is much less disturbed. Patients with parietal lesions sparing the cortex lining the anterior intraparietal sulcus showed intact grasping behavior. Complementary evidence was obtained from functional MRI in normal control subjects showing a specific activation of the anterior lateral bank of the intraparietal sulcus during grasping. In conclusion, this combined lesion and activation study suggests that the anterior lateral bank of the intraparietal sulcus, possibly including the human homologue of the anterior intraparietal area, mediates the processing of sensorimotor integration of precisely tuned finger movements in humans.


Nature Medicine | 2007

Liver cell death and anemia in Wilson disease involve acid sphingomyelinase and ceramide

Philipp A. Lang; M. Schenck; Jan P. Nicolay; Jan U. Becker; Daniela S. Kempe; Adrian Lupescu; Saisudha Koka; Kerstin Eisele; Barbara A. Klarl; H. Rübben; Kurt Werner Schmid; Klaus Mann; Sibylle Hildenbrand; Harald Hefter; Stephan M. Huber; Thomas Wieder; A. Erhardt; Dieter Häussinger; Erich Gulbins; Florian Lang

Wilson disease is caused by accumulation of Cu2+ in cells, which results in liver cirrhosis and, occasionally, anemia. Here, we show that Cu2+ triggers hepatocyte apoptosis through activation of acid sphingomyelinase (Asm) and release of ceramide. Genetic deficiency or pharmacological inhibition of Asm prevented Cu2+-induced hepatocyte apoptosis and protected rats, genetically prone to develop Wilson disease, from acute hepatocyte death, liver failure and early death. Cu2+ induced the secretion of activated Asm from leukocytes, leading to ceramide release in and phosphatidylserine exposure on erythrocytes, events also prevented by inhibition of Asm. Phosphatidylserine exposure resulted in immediate clearance of affected erythrocytes from the blood in mice. Accordingly, individuals with Wilson disease showed elevated plasma levels of Asm, and displayed a constitutive increase of ceramide- and phosphatidylserine-positive erythrocytes. Our data suggest a previously unidentified mechanism for liver cirrhosis and anemia in Wilson disease.


Annals of Internal Medicine | 1991

Wilson Disease: Clinical Presentation, Treatment, and Survival

Wolfgang Stremmel; Karl-Wilhelm Meyerrose; Claus Niederau; Harald Hefter; Georg Kreuzpaintner; Georg Strohmeyer

OBJECTIVE To evaluate the diagnostic features, clinical course, and overall long-term survival of patients with Wilson disease. DESIGN Retrospective cohort study with a mean follow-up period of 14.2 years. SETTING A university medical center and a community hospital. PATIENTS Fifty-one consecutive patients with Wilson disease were evaluated between 1957 and 1989. INTERVENTIONS Patients were treated with D-penicillamine (600 to 1800 mg/d). Two patients with end-stage liver disease had liver transplantation. MAIN RESULTS Initial symptoms occurred at a mean age of 15.5 years. At diagnosis, the most common neurologic signs were dysarthria, tremor, writing difficulties, and ataxia followed by hypersalivation and headache. Somatic symptoms included abdominal pain, hepatomegaly, splenomegaly, cirrhosis of the liver, and thrombocytopenia. The mean serum concentrations of ceruloplasmin and copper were 44 mg/L and 4.7 mumol/L, respectively. The mean basal urinary copper excretion was 5.5 mumol/d, and the mean hepatic copper concentration was 19.6 mumol/g dry weight. Free serum copper concentration (mean, 2.7 mumol/L) was a reliable indicator of disease and was useful in assessing the effectiveness of therapy (values less than 1.6 mumol/L). Treatment with D-penicillamine improved most of the hematologic and neurologic abnormalities but had little effect on hepatomegaly and splenomegaly and did not reverse cirrhosis. Two patients died of fulminant hepatic failure during the observation period, whereas two others with end-stage liver disease had successful liver transplantation and remain asymptomatic. Long-term survival of patients with Wilson disease was similar to that of age- and sex-matched controls. CONCLUSION Our results suggest that long-term treatment of patients with Wilson disease with D-penicillamine can relieve symptoms and improve prognosis.


European Journal of Neuroscience | 2001

Neural correlates of religious experience.

Nina P. Azari; Janpeter Nickel; Michael Niedeggen; Harald Hefter; Lutz Tellmann; Hans Herzog; Petra Stoerig; Dieter Birnbacher; Rüdiger J. Seitz

The commonsense view of religious experience is that it is a preconceptual, immediate affective event. Work in philosophy and psychology, however, suggest that religious experience is an attributional cognitive phenomenon. Here the neural correlates of a religious experience are investigated using functional neuroimaging. During religious recitation, self‐identified religious subjects activated a frontal–parietal circuit, composed of the dorsolateral prefrontal, dorsomedial frontal and medial parietal cortex. Prior studies indicate that these areas play a profound role in sustaining reflexive evaluation of thought. Thus, religious experience may be a cognitive process which, nonetheless, feels immediate.


Pain | 2006

Efficacy and safety of a single botulinum type A toxin complex treatment (Dysport®) for the relief of upper back myofascial pain syndrome: Results from a randomized double-blind placebo-controlled multicentre study

Hartmut Göbel; A. Heinze; Gerhard Reichel; Harald Hefter; Reiner Benecke

&NA; Botulinum type A toxin (BoNT‐A) has antinociceptive and muscle‐relaxant properties and may help relieve the symptoms of myofascial pain syndrome. In this study we evaluated the efficacy and tolerability of BoNT‐A (Dysport®) in patients with myofascial pain syndrome of the upper back. We conducted a prospective, randomized, double‐blind, placebo‐controlled, 12‐week, multicentre study. Patients with moderate‐to‐severe myofascial pain syndrome affecting cervical and/or shoulder muscles (≥10 trigger points, disease duration 6–24 months) were randomized to Dysport® or saline. Injections were made into the 10 most tender trigger points (40 units per site). The primary outcome was the proportion of patients with mild or no pain at week 5. Secondary outcomes included changes in pain intensity and the number of pain‐free days per week. Tolerability and safety were also assessed. At week 5, significantly more patients in the Dysport® group reported mild or no pain (51%), compared with the patients in the placebo group (26%; p = 0.002). Compared with placebo, Dysport® resulted in a significantly greater change from baseline in pain intensity during weeks 5–8 (p < 0.05), and significantly fewer days per week without pain between weeks 5 and 12 (p = 0.036). Treatment was well tolerated, with most side effects resolving within 8 weeks. In conclusion, in patients with upper back myofascial pain syndrome, injections of 400 Ipsen units of Dysport® at 10 individualised trigger points significantly improved pain levels 4–6 weeks after treatment. Injections were well tolerated.


Journal of Neurology | 1990

Motor dysfunction in HIV-infected patients without clinically detectable central-nervous deficit

Gabriele Arendt; Harald Hefter; C. Elsing; Georg Strohmeyer; Hans-Joachim Freund

SummaryMotor tests were performed in 50 HIV-infected patients in all stages according to the current CDC classification, but without any clinically evident central nervous system deficit, and the results compared with an age-matched control group. Patients were excluded from the study if there was alcohol or drug abuse, fever and/or opportunistic cerebral infection. The parameters tested were postural tremor of the outstretched hands, most rapid voluntary alternating index finger movements (MRAM) and rise time of most rapid index finger extensions (MRC). Whereas tremor peak frequencies did not differ significantly in the patients and controls, MRAM and rise times of MRCs showed significant slowing in the patient group. Morphologically, the motor test performance of the HIV-infected patients was similar to that of patients with manifest basal ganglia disease (Parkinsons, Huntingtons and Wilsons diseases). MRI scans of all patients were normal. It is concluded that in HIV-infected patients there is a very early subclinical central nervous system affection, especially of the basal ganglia, which is detectable with appropriate, quantitative motor function tests. These functional abnormalities precede the structural alterations in the MRI scans.


Movement Disorders | 2001

Effects of bilateral pallidal or subthalamic stimulation on gait in advanced Parkinson's disease

Niels Allert; Jens Volkmann; S. Dotse; Harald Hefter; Volker Sturm; Hans-Joachim Freund

Bilateral high‐frequency stimulation of the internal globus pallidus (GPi) and the subthalamic nucleus (STN) both alleviate akinesia, rigidity, and tremor in idiopathic Parkinsons disease. To test the specific effect of these procedures on gait, we used quantitative gait analysis in addition to relevant subscores of the Unified Parkinsons Disease Rating Scale in a group of 10 patients with advanced Parkinsons disease treated by GPi stimulation and eight patients treated by STN stimulation. Patients were assessed before and 3 months after surgery. Thirty age‐matched healthy subjects served as controls. The non‐random selection allowed a descriptive but no direct statistical comparison of the respective procedure. Gait analysis showed significant stimulation‐induced improvements of spatiotemporal gait and step parameters in both patient groups. Moreover, the effects on step length and cadence suggested a differential effect of both basal ganglia targets. Hence, the increase in gait velocity in the STN group was almost exclusively due to a significant increase in step length, while in the GPi group statistically non‐significant increases in both step length and cadence contributed.


Clinical Gastroenterology and Hepatology | 2013

Efficacy and Safety of Oral Chelators in Treatment of Patients With Wilson Disease

Karl Heinz Weiss; Florentine Thurik; Daniel Gotthardt; Mark Schäfer; Ulrike Teufel; Franziska Wiegand; Uta Merle; Daniela Ferenci–Foerster; A Maieron; Rudolf E. Stauber; Heinz Zoller; Hartmut Schmidt; Ulrike Reuner; Harald Hefter; Jean Marc Trocello; Roderick H. J. Houwen; Peter Ferenci; Wolfgang Stremmel

BACKGROUND & AIMS Wilson disease is a genetic copper storage disorder that causes hepatic and neurologic symptoms. Chelating agents (D-penicillamine, trientine) are used as first-line therapies for symptomatic patients, but there are few data from large cohorts. We assessed the safety of D-penicillamine and trientine therapy and outcomes of patients with Wilson disease. METHODS We performed a retrospective analysis of data on 380 patients with Wilson disease from tertiary care centers in Germany and Austria, and 25 additional patients from the EUROWILSON registry. Chelator-based treatment regimens were analyzed for their effect on neurologic and hepatic symptoms and for adverse events that led to discontinuation of therapy (Kaplan-Meier estimation; data were collected for a mean of 13.3 y after therapy began). RESULTS Changes in medication were common, resulting in analysis of 471 chelator monotherapies (326 patients receiving D-penicillamine and 141 receiving trientine). Nine of 326 patients treated with D-penicillamine and 3 of 141 patients given trientine underwent liver transplantation. Adverse events leading to discontinuation of treatment were more frequent among those receiving D-penicillamine than trientine (P = .039). Forty-eight months after therapy, hepatic deterioration was reported in only 4 of 333 patients treated initially with a chelating agent. Hepatic improvements were observed in more than 90%, and neurologic improvements were observed in more than 55%, of therapy-naive patients, and values did not differ significantly between treatments. However, neurologic deterioration was observed less frequently in patients given D-penicillamine first (6 of 295) than those given trientine first (4 of 38; P = .018). CONCLUSIONS Chelating agents are effective therapies for most patients with Wilson disease; D-penicillamine and trientine produce comparable outcomes, although D-penicillamine had a higher rate of adverse events. Few patients receiving chelation therapy had neurologic deterioration, which occurred more frequently in patients who received trientine.


Journal of Neurology | 2004

Is levodopa toxic

Thomas Müller; Harald Hefter; Roland Hueber; Wolfgang H. Jost; Klaus L. Leenders; Per Odin; Johannes Schwarz

Abstract.The objective of this workshop was to review and discuss the debate on neurotoxicity of levodopa in the treatment of Parkinson’s disease (PD) with consideration of preclinical and clinical findings. We concluded that in particular preclinical outcomes of in vitro models of neurodegeneration describe neurotoxic effects of levodopa, whereas trials in animal models provided controversial results. To date, clinical trials in PD patients showed no convincing proof of direct neurotoxic effects of levodopa on progression of neurodegeneration with various applied functional imaging techniques particularly with specific radiotracers for nigral dopaminergic neurotransmission. However, the controversy on neurotoxicity of levodopa only partially considered indirect mechanisms, i. e. levodopa-associated homocysteine elevation. But there is accumulating evidence that this long-term side effect of chronic levodopa administration dose dependently individually contributes to progression of neurodegeneration due to increased release of neurotoxins, induction of oxidative stress and mitochondrial dysfunction according to results of in vitro and animal trials and to at least peripheral neuronal degeneration and increased risk for onset of atherosclerosis-related disorders according to clinical trials in PD patients. From this point of view we demand that future research on the efficacy and putative neurotoxicity of antiparkinsonian compounds should also consider putative toxic longterm effects of drug administration and should look for putative peripheral biomarkers and individual, environmental or nutritative risk factors in order to establish a preventive therapy, i. e. folic acid administration in the case of levodopa-associated homocysteine elevation.


Experimental Brain Research | 1993

Role of the cerebellum in visuomotor coordination I. Delayed eye and arm initiation in patients with mild cerebellar ataxia

Susan H. Brown; Kirn R. Kessler; Harald Hefter; J. D. Cooke; Hans-Joachim Freund

The initiation of coupled eye and arm movements was studied in six patients with mild cerebellar dysfunction and in six age-matched control subjects. The experimental paradigm consisted of 40 deg step-tracking elbow movements made under different feedback conditions. During tracking with the eyes only, saccadic latencies in patients were within normal limits. When patients were required to make coordinated eye and arm movements, however, eye movement onset was significantly delayed. In addition, removal of visual information about arm versus target position had a pronounced differential effect on movement latencies. When the target was extinguished for 3 s immediately following a step change in target position, both eye and arm onset times were further prolonged compared to movements made to continuously visible targets. When visual information concerning arm position was removed, onset times were reduced. Eye and arm latencies in control subjects were unaffected by changes in visual feedback. The results of this study clearly demonstrate that, in contrast to earlier reports of normal saccadic latencies associated with cerebellar dysfunction, initiation of both eye and arm movements is prolonged during coordinated visuomotor tracking thus supporting a coordinative role for the cerebellum during oculo-manual tracking tasks.

Collaboration


Dive into the Harald Hefter's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Gabriele Arendt

University of Düsseldorf

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Marek Moll

University of Düsseldorf

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Volker Hömberg

University of Düsseldorf

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge