Showing papers by "Wilfried Kuhn published in 1995"

Distorted color discrimination in 'de novo' parkinsonian patients.

Abstract: Article abstract—We performed the Farnsworth-Munsell 100–hue test in 16 “de novo” patients with Parkinson9s disease and 16 age-matched controls to determine their color discrimination ability. “he mean total error score in patients was significantly elevated as compared with controls (64.6 in patients versus 16.0 in controls). We conclude that the impairment of color discrimination may be an early sign in Parkinson9s disease.

Plasma harman and norharman in Parkinson's disease.

Abstract: Several lines of evidence suggest that endogenous and exogenous toxins may play a major role in the pathogenesis of Parkinson's disease (PD). In the brain aromatic beta-carbolines, like harman or norharman, may be formed by cyclization of indoleamines. Because of the structural similarity to MPTP, beta-carbolines have been proposed as endogenous toxins. For further elucidation of the role of beta-carbolines in neurodegenerative disorders, harman and norharman plasma levels were measured in 36 patients with PD and compared to an age- and sex-matched control group. Plasma levels of norharman in PD were significantly higher compared to the control group. Harman in the plasma of Parkinsonian patients was also elevated compared to the controls, but this difference was not significant. On the one hand these results may suggest a possible role of beta-carbolines in the pathophysiological processes initiating PD. But on the other hand one may speculate that elevated levels of norharman and harman are due to an endogenous upregulation, caused by unknown metabolic processes to reduce oxidative stress by inhibiting e.g. monoaminooxidases in neurons.

Neuroimmune mechanisms in Parkinson's disease.

Abstract: The potential role of immune mechanisms in the pathogenesis of Parkinson's disease is still a matter of controversy. Both peripheral and central immunological disturbances have been reported. It is possible that this altered function of the immune system is responsible for autodestruction of neurons in Parkinson's disease and other neurodegenerative disorders. In this case possible neuroprotective therapeutic strategies could be developed. However, further investigations are necessary to elucidate the conditions of normal or pathologic interaction between the brain and the immune system.

Color vision in Parkinson's disease: missing influence of amantadine sulphate.

Abstract: In recent studies, disorders of chromatic and achromatic vision in parkinsonian patients have been demonstrated; these could be partially restored after application of L-Dopa. In this study, the effect of a 3-day infusion therapy with amantadine sulphate on color vision was evaluated in 19 parkinsonian patients by use of the Farnsworth-Munsell 100-Hue test. Under this treatment, the motor symptoms of parkinsonism improved significantly as assessed by the part "motor examination" of the Unified Parkinson's Disease Rating Scale (UPDRS). However, the total error scores of the Farnsworth-Munsell 100-Hue test before and after amantadine sulphate infusions were unchanged [before therapy, 94.53 (SD = 52.09); after therapy, 99.5 (SD = 58.81)]. From these results, it can be concluded that the pathophysiology of dopaminergic pathways in the visual system differs from that of the basal ganglia.

Alterations in chromatic contour perception in de novo parkinsonian patients

Abstract: Recently abnormalities of chromatic visual perception were reported in treated patients with Parkinson’s disease (PD). We studied 28 previously untreated Parkinsonian patients and 28 age- and sex-matc

Intravenous application of amantadine and antiparkinsonian efficacy in Parkinsonian patients.

Abstract: The aim of this study was to estimate the pharmacokinetic properties of amantadine after infusion and subsequent peroral application of two galenic forms at a daily dose of 200 mg. In addition, the pharmacodynamics of the different treatment regimes evaluated by the motoric items of the UPDRS were investigated. Furthermore, the relationship between plasma levels and clinical efficacy was evaluated. To address these questions Parkinsonian patients were randomly assigned to 3 groups: infusion-tablet, infusion-capsule, infusion-infusion. Parenteral application of amantadine sulphate provided a rapid improvement in Parkinsonian patients within the first three days. This response could be stabilized and even improved further by peroral treatment for another 3 days. The change from intravenous to peroral tablet therapy was followed by a transient decrease in cmax and AUC(o-t) being not reflected by a reduction in clinical efficacy. Conversely, a persistent reduction of the plasma concentration after switching to the capsule therapy was paralleled by a somewhat unfavourable clinical response.

Chronic intoxication with lead- and sulfur compounds may produce Parkinson's disease.

Abstract: Parkinson's disease was found in three post office workers who were in close contact with lead-sulfate batteries over a period between 1947 and 1983. The workers had been working in a charging station for lead storage batteries used for the battery-traction of post wagons. Parkinson's disease was diagnosed by the characteristic features of rigidity, tremor and elements of hypo-, brady- and akinesia. Additional symptoms were: bradyphrenia (n = 3), memory deficits (n = 3), depressive symptoms (n = 2) and peripheral neuropathy (n = 2). We hypothesize that the parkinsonian symptoms of these post office workers are primarily caused by lead or lead compounds. However a possible toxicity of sulfur containing compounds cannot be ruled out.

Pharmacological effects of dopaminergics and amantadine on color discrimination in Parkinson's disease

Abstract: In recent studies disorders of chromatic and achromatic vision in Parkinsonian patients have been demonstrated, which were partially reversible after application of L-dopa Up to now the origin of visual disorders in Parkinson's disease (PD) and the effect of further anti-Parkinsonian drugs are unclear In this study, the authors evaluated the effect of L-dopa, apo-morphine and amantadine on color vision in PD by means of the Farns-worth-Munsell ioo hue test (FM) Nineteen patients underwent the color vision test before and after the oral administration of the morning medication with L-dopa, 24 patients before and after subcutaneous application of apomorphine, and 19 further patients were tested before and after an infusion therapy with amantadine (200 mg/d) over three days Under those treatment conditions the motor symptoms of Parkinsonism improved significantly in all three groups as assessed by part HI of the Unified Parkinson's Disease Rating Scale (UPDRS) Before the morning medication with L-dopa t

Exogenous stimulation of NGF synthesis by catecholamines and their analogues.

Abstract: In humans different problems are associated with the direct application of neurotrophic factors like e.g. nerve growth factor (NGF). Therefore increasing attention has been focused on the concept of pharmacological stimulation of endogenous synthesis of trophic factors. For various compounds, especially catecholamines and their analogues, it has been demonstrated that induction of synthesis of NGF in glial and neuronal cells is possible. However, further experiments are necessary to confirm these results under in vivo conditions and to ensure safe and efficient clinical application.