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Albert C Ludolph

Publications and source records attributed to Albert C Ludolph.

At least 37 records · Page 2Linked to original sources
PubMed2005

Motor protein diseases of the nervous system.

Motor proteins link concepts of impaired axonal transport with concepts of impaired energy metabolism in motor neuron disease. Thus it is not surprising that in recent years several reports on the relevance of motor protein function in mice models for motor neuron disease as well as motor neuron patients have appeared. This article summarizes the broad spectrum of neurological phenotypes, which are caused by alterations of motor protein function. This is likely to add to the understanding of motor neuron disease and may be relevant in terms of future therapeutic approaches.

Animals↗
PubMed2005

Global brain atrophy and corticospinal tract alterations in ALS, as investigated by voxel-based morphometry of 3-D MRI.

In ALS, advanced magnetic resonance imaging (MRI) techniques are increasingly used to investigate the underlying pathology. In this study, the technique of voxel-based morphometry (VBM) was applied to 3-D MRI data in ALS patients to localize regional grey and white matter changes. Twenty-two ALS patients (mean age 58+/-9 years) with clinically definite ALS by revised El Escorial criteria were studied. None of the patients had any signs of associated frontotemporal dementia. High-resolution 3-D MRI data sets of the whole brain, collected on a 1.5 T scanner, were analysed by statistical parametric mapping (SPM) and VBM in comparison to an age-matched normal data base consisting of 22 healthy volunteers (mean age 59+/-11 years), for grey matter and white matter segments separately. Global brain atrophy was assessed by calculation of brain parenchymal fractions (BPF). In ALS patients, BPF were significantly reduced compared to controls (p = 0.0003), indicating global brain atrophy. Regional decreases of grey matter density were found in the ALS patients at corrected p<0.01 in the right-hemispheric primary motor cortex (area of the highest Z-score) and in the left medial frontal gyrus. Furthermore, regional white matter alterations were observed along the corticospinal tracts bilaterally and in multiple smaller areas including corpus callosum, cerebellum, frontal and occipital subcortical regions. Besides considerable global atrophy in ALS, the topography of ALS-associated cerebral morphological changes could be mapped using VBM, in particular white matter signal changes along the bilateral corticospinal tracts, but also in extra-motor areas. VBM might be a potential tool to visualize disease progression in future longitudinal studies.

Adult↗
PubMed2005

Preclinical trials--an update on translational research in ALS.

Translational research has become a strategy which describes the steps from in vitro experimental therapy, its translation into experimental animals and finally to humans. However, this translation of hypotheses from one of these levels to another faces a number of difficulties which are currently of major interest for the development of therapeutics. In particular, in the previously untreatable motor neuron diseases, the steps from genes to transgenic animals and finally to the patient have proven difficult. High expectations have not met with the transfer of numerous therapies from experimental animals to men; there are many in- and outside the field which already question the value of animal models. It is the opinion of the authors that we should not dismiss the models before we have not defined generally accepted standards of protocols for therapeutic studies in experimental animals. Only if a generally agreed standardized and validated methodology in mice cannot predict the human response to therapeutics, an animal model should be abandoned. In contrast, the value of translating genetic findings to experimental animals and men is currently shown for motor proteins; in particular the functional impact of dynactin and dynein for the integrity of motor neurons of rodents and men are in the center of interest.

Amyotrophic Lateral Sclerosis↗
PubMed2005

Severity of depressive symptoms and quality of life in patients with amyotrophic lateral sclerosis.

OBJECTIVES: The authors aimed at investigating the occurrence of depression and the level of quality of life in patients with amyotrophic lateral sclerosis (ALS), an incurable neurodegenerative disease leading to progressive motor paralysis. They further wished to elucidate correlates of depression and quality of life, such as physical impairment, time since diagnosis, age, sex, and education. Additionally, the authors attempted to confirm previous studies that had shown quality of life to be underestimated by partners or caregivers. METHODS: To assess severity of depressive symptoms, the authors used Beck's Depression Inventory (BDI) and the ALS-Depression Inventory. To assess the patients' quality of life, they used the Scales to Assess Quality of Life. The same questionnaire was presented to partners or caregivers to estimate the patients' quality of life. RESULTS: Severity of depressive symptoms was everything from not depressed to clinically relevant depressed. On average, quality of life was rated as satisfactory. Severity of depressive symptoms and quality of life showed a moderate positive relation to physical impairment and a weak negative relation to time since diagnosis. Partners or caregivers rated patients' quality of life significantly lower than did the patients. CONCLUSIONS: Although depression occurs among ALS patients, it is not inevitable. Patients can remain free of depression and maintain a good quality of life. Depression should be treated, and patients have to be provided with unbiased information, including their medical and palliative care options.

Adult↗
PubMed2005

Mechanisms of disease: motoneuron disease aggravated by transgenic expression of a functionally modified AMPA receptor subunit.

To reveal whether increased Ca2+ permeability of glutamate AMPA channels triggered by the transgene for GluR-B(N) induces decline in motor functions and neurodegeneration in the spinal cord, we evaluated growth, motor coordination, and spinal reflexes in transgenic GluR-B(N) and wild-type (wt) mice. To reveal whether the transgenic GluR-B(N) expression aggravates the course of motoneuron disease in SOD1 mice, we mated heterozygous GluR-B(N) and SOD1 [C57BL6Ico-TgN(hSOD1-G93A)1Gur] mice to generate double-transgenic progeny. The phenotypic sequelae in mice carrying mutations were evaluated by monitoring growth, motor coordination, and survival. Neuronal degeneration was assessed by morphological and stereological analysis of spinal cord and brain. We found that transgenic expression in mice of GluR-B(N)-containing glutamate AMPA receptors with increased Ca2+ permeability leads to a late-onset degeneration of neurons in the spinal cord and decline of motor functions. Neuronal death progressed over the entire life span, but manifested clinically in late adulthood, resembling the course of a slow neurodegenerative disorder. Additional transgenic expression of mutated human SOD1 accelerated disease progression, aggravated severity of motor decline, and decreased survival. These observations reveal that moderate, but persistently elevated Ca2+ influx via glutamate AMPA channels causes degeneration of spinal motoneurons and motor decline over the span of life. These features resemble the course of sporadic amyotrophic lateral sclerosis (ALS) in humans and suggest that modified function of glutamate AMPA channels may be causally linked to pathogenesis of ALS.

Animals↗
PubMed2004

Age-dependent changes in MRI of motor brain stem nuclei in a mouse model of ALS.

Mice over-expressing the mutant human G93A-SOD1 are widely used as an animal model of amyotrophic lateral sclerosis (ALS). ALS is characterized by progressive degeneration of motor neurons in the motor cortex, brain stem and spinal cord. The underlying mechanisms for the selective death of motor neurons are still uncertain. To study factors that cause selective neuron degeneration or therapeutic approaches to delay the progression of the disease, a method is required to monitor the state of motor neurons under in-vivo conditions. Here, we demonstrate that in G93A-SOD1 mice the MRI signal intensities of nucleus V, VII, XII, and nucleus ambiguus show a time-dependent increase starting around day 90, parallel to first behavioral signs of a motoneuron disorder.

Aging↗
PubMed2004

Chromosomal translocation t(18;21)(q23;q22.1) indicates novel susceptibility loci for frontotemporal dementia with ALS.

A chromosomal translocation t(18;21)(q23;q22) is reported in a patient with frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). We exclude the physical involvement and silencing of the ALS-linked gene for copper/zinc superoxide dismutase (SOD1) on chromosome 21q22.1. The breakpoints are assigned to sequences flanked by the markers ATA1H06, D18S462, D21S1915, and D21S1898. These critical regions may contain susceptibility loci for FTD associated with ALS.

Amyotrophic Lateral Sclerosis↗
PubMed2004

Imaging of activated microglia with PET and [11C]PK 11195 in corticobasal degeneration.

Positron emission tomography (PET) using [(11)C]PK 11195, a ligand for peripheral benzodiazepine receptor binding sites, offers the opportunity to image activated microglia in vivo. This tool may therefore be used to display the occurrence of microglial activation in the course of neurodegeneration. A patient with the clinical diagnosis of corticobasal degeneration (CBD) and left-sided symptoms was studied using fluorodeoxyglucose (FDG) and [(11)C]PK 11195 PET. We found a marked right hemispheric hypometabolism and asymmetric microglial activation in corresponding areas of the basal ganglia and right temporal and parietal cortex. [(11)C]PK 11195 PET suggests involvement of microglial activation in the pathogenesis of CBD.

Aged↗
PubMed2004

Rasagiline alone and in combination with riluzole prolongs survival in an ALS mouse model.

Rasagiline is an antiapoptotic compound with neuroprotective potential. We examined its neuroprotective effect alone and in combination with the putative glutamate release blocker riluzole in the G93A model of familial amyotrophic lateral sclerosis (fALS). Endpoints of experimental treatment were survival and motor activity. The drug had a significant dose-dependent therapeutic effect on both preclinical and clinical motor function and survival of the animals. We also found that the combination of rasagiline with riluzole is safe and increases survival by about 20 % in a dose-dependent manner. Therefore, we conclude that the combination of rasagiline and riluzole is a promising clinical combination for the improvement of current neuroprotective treatment strategies of ALS.

Amyotrophic Lateral Sclerosis↗
PubMed2003

Amyotrophic lateral sclerosis: disease stage related changes of tau protein and S100 beta in cerebrospinal fluid and creatine kinase in serum.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease leading to progressive cell death of upper and lower motor neurons and reactive astrogliosis. Two proteins which may be relevant in this respect (tau and S100 beta) were studied in cerebrospinal fluid (CSF) next to routine parameters in 20 patients with sporadic ALS and 20 age-matched controls. Serum levels of creatine kinase (CK) were also determined to monitor the muscular involvement. S100 beta showed a significant decrease in CSF over the disease course (P=0.024). CSF tau as well as serum CK were elevated in 70% of the ALS patients. While highest CSF tau levels were found rather in the early disease stages, serum CK showed a shift of the peak values to several months later. Elevation of the CSF/serum albumin quotient occurred in 20% of the cases most likely representing a non-specific finding in ALS.

Adult↗
PubMed2003

Quantification of brain atrophy in patients with myotonic dystrophy and proximal myotonic myopathy: a controlled 3-dimensional magnetic resonance imaging study.

Myotonic dystrophy (DM1) and proximal myotonic myopathy (PROMM or DM2) are two distinct muscular disorders with multisystemic involvement. Both have previously been reported to be associated with cognitive impairment and white matter lesions detected by cerebral magnetic resonance imaging (MRI). In this study, the extent of brain atrophy was investigated in vivo in ten DM1 and nine PROMM patients in comparison to age-matched healthy controls for each group. The diagnosis was confirmed by DNA analysis of all patients. As a quantitative marker, the ratio of brain parenchymal to intracranial volume, called brain parenchymal fraction (BPF), was calculated from 3-dimensional MRI data using an automated analysis technique. Compared to age-matched healthy controls (mean BPF 0.852 +/- 0.032), the BPF in DM1 patients (0.713 +/- 0.031) was highly significantly decreased (P < 0.001). In contrast, the PROMM patients (mean BPF 0.792 +/- 0.029) showed only slightly decreased BPF values (P < 0.05). BPF was not significantly correlated to any of the clinical or genetic parameters in both diseases (disease duration, motor score, educational level, and number of CTG repeats in the expanded allele). In summary, global brain atrophy was demonstrated to occur in both diseases, but was more severely manifestated in DM1 patients.

Adolescent↗
PubMed2003

Differential regulation of 5' splice variants of the glutamate transporter EAAT2 in an in vivo model of chemical hypoxia induced by 3-nitropropionic acid.

Defective glutamate uptake has been implicated as a pathogenic event of neuronal damage related to cerebral ischemia and hypoxia. In several models of ischemia-hypoxia, a reduced immunoreactivity and altered RNA expression of excitatory amino acid transporter 2 (EAAT2), the major excitatory amino acid transporter, have been reported. However, the gene regulation of EAAT2 under these conditions is incompletely understood. In this study, we investigated alternative splicing of EAAT2 in an in vivo mouse model of chemical hypoxia as induced by 3-nitropropionic acid (3-NP). The neurotoxin 3-NP is an inhibitor of mitochondrial energy production. Furthermore, it is known to inhibit glutamate reuptake directly, representing at least one of the mechanisms responsible for 3-NP-induced neurodegeneration. Here we report an expression analysis of five known (mEAAT2/5UT1-5) and two novel (mEAAT2/5UT6, -7) 5' splice variants of EAAT2 using semiquantitative PCR. The RNA expression was studied at 2, 12, 24, 48, and 72 hr and 7 days after 3-NP administration. mEAAT2/5UT4 and mEAAT2/5UT5 were up-regulated in the frontal cortex and down-regulated in the hippocampus 12-72 hr after chemical hypoxia. In the cerebellum, there was an increased expression of mEAAT2/5UT4 and a down-regulation of mEAAT2/5UT5. mEAAT2/5UT3 show a different regional expression pattern, being regulated in the cerebellum only. mEAAT2/5UT1-7 encoded distinct 5' regulatory sequences, including conserved elements of translational control. It is easily conceivable that expression alterations of 5' splice variants of EAAT2 are related to glutamate transporter malfunction after chemical hypoxia. Our findings contribute to the hypothesis that RNA splicing events can serve as a molecular mechanism of posthypoxic gene regulation.

Alternative Splicing↗
PubMed2003

Age-related brain parenchymal fraction is significantly decreased in young multiple sclerosis patients: a quantitative MRI study.

The extent of brain atrophy was determined in 33 patients with multiple sclerosis (MS) and in 60 healthy subjects (21-76 years) by calculating brain parenchymal fractions (BPF, the ratio of brain parenchymal to intracranial volume) from 3D MRI. Within the normal data base, subjects at higher ages showed significantly lower BPF values. In younger MS patients, BPF was significantly decreased compared with age-matched controls (20-29 years, p= 0.0022; 30-39 years, =p 0.0001; 40-49 years,p = 0.0444) and was significantly correlated with disease duration and disease severity, but not with the number of detectable MS lesions. Determination of age-related BPF demonstrated significant brain atrophy in early MS and can be considered as a useful biological marker for monitoring MS.

Adult↗
PubMed2003

Longitudinal effects of noninvasive positive-pressure ventilation in patients with amyotrophic lateral sclerosis.

OBJECTIVE: To evaluate the duration of benefit on symptoms, quality of life, and survival derived from the use of noninvasive positive-pressure ventilation by patients with amyotrophic lateral sclerosis. DESIGN: In this prospective, cohort study, 30 of 36 consecutively referred symptomatic patients tolerated nightly noninvasive positive-pressure ventilation and undertook pulmonary function testing and 12 symptom and quality-of-life instruments concerning sleep quality, daytime sleepiness, physical fatigue, mental fatigue, and depression that were administered during a 10-mo period. RESULTS: With treatment, there was a significant improvement in the majority of patients in sleep quality, daytime sleepiness, physical fatigue, and depression; however, significant improvements lasted for up to 10 mo only in sleep quality. Partial pressure of arterial oxygen, partial pressure of arterial carbon dioxide, and oxyhemoglobin saturation remained stable or even improved for up to 7 mo during use of part-time noninvasive positive-pressure ventilation. A total of 14 patients had survival prolonged by continuous dependence on noninvasive positive-pressure ventilation. CONCLUSIONS: Noninvasive positive-pressure ventilation provides a long-lasting benefit on symptoms and quality of life indicators for amyotrophic lateral sclerosis patients and should be offered to all patients with symptoms of sleep disordered breathing or inspiratory muscle dysfunction. It can also prolong tracheostomy-free survival.

Adult↗
PubMed2002

Ifosfamide encephalopathy presenting with asterixis.

CNS toxic effects of the antineoplastic agent ifosfamide (IFX) are frequent and include a variety of neurological symptoms that can limit drug use. We report a case of a 51-year-old man who developed severe, disabling negative myoclonus of the upper and lower extremities after the infusion of ifosfamide for plasmacytoma. He was awake, revealed no changes of mental status and at rest there were no further motor symptoms. Cranial magnetic resonance imaging and extensive laboratory studies failed to reveal structural lesions of the brain and metabolic abnormalities. An electroencephalogram showed continuous, generalized irregular slowing with admixed periodic triphasic waves indicating symptomatic encephalopathy. The administration of ifosfamide was discontinued and within 12 h the asterixis resolved completely. In the patient described, the presence of asterixis during infusion of ifosfamide, normal laboratory findings and imaging studies and the resolution of symptoms following the discontinuation of the drug suggest that negative myoclonus is associated with the use of IFX.

Dyskinesia, Drug-Induced↗
PubMed2002

X-linked bulbospinal neuronopathy: Kennedy disease.

OBJECTIVE: To characterize the earliest symptoms of X-linked bulbospinal neuronopathy (Kennedy disease [KD]) during the course of the disease, including a definition of the age of onset. METHODS: We describe the earliest symptoms, signs on clinical investigation, electrophysiological and muscle biopsy specimen findings, and creatine kinase levels in 34 patients with KD. Correlations were made among the CAG-repeat length and clinical symptoms, age at onset, and the presence of electrophysiological and laboratory findings. RESULTS: Our findings indicate that the age at onset of KD is in adolescence which is earlier than previously thought. Most frequently early symptoms are gynecomastia, muscle pain, and premature muscular exhaustion. Weakness is not a typical initial symptom and is frequently found in distal limbs if present early. We found a correlation between the of number of CAG repeats and the age at onset of weakness but not to the age at onset of KD. Furthermore, no correlations were found between the occurrence of gynecomastia, tremor, increased creatine kinase levels, and additional myopathic changes in muscle biopsy specimens. CONCLUSIONS: Our data show that KD is a multisystem disorder with onset in adolescence. Because of the heterogeneity of clinical presentation and no correlation between the number of CAG repeats and most of the clinical hallmarks of KD, we suggest that other environmental or genetic factors contribute to the manifestation of specific organ systems in KD.

Adult↗
PubMed2002

CuZn-superoxide dismutase in D90A heterozygotes from recessive and dominant ALS pedigrees.

Mutations in CuZn-superoxide dismutase (CuZn-SOD) have been linked to ALS. In most cases ALS is inherited as a dominant trait and there is marked reduction in CuZn-SOD activity in samples from the patients. The D90A mutation, however, mostly causes ALS as a recessive trait and shows near normal CuZn-SOD activity. A few familial and sporadic ALS cases heterozygous for the D90A mutation have also been found. Haplotype analysis of both types of D90A families has suggested that all recessive cases share a common founder and may carry a protective factor located close to the D90A mutant CuZn-SOD locus. To search for effects of a putative protective factor we analysed erythrocytes from D90A heterozygous individuals for SOD activity by a direct assay, subunit composition by immunoblotting, and zymogram pattern formed by isoelectric focusing and SOD staining. Included were heterozygotes from 17 recessive families, and from 2 dominant families and 4 apparently sporadic cases. The CuZn-SOD activity in the recessive and dominant groups was found to be equal, and 95% of controls. The ratio between mutant and wildtype subunits was likewise equal and 0.8:1 in both groups. The zymograms revealed multiple bands representing homo- and heterodimers. There were, however, no differences between the groups in patterns or in ratios between the molecular forms. In conclusion we find no evidence from analyses in erythrocytes that the putative protective factor in recessive families acts by simply downregulating the synthesis or altering the molecular structure or turnover of the mutant enzyme.

Amyotrophic Lateral Sclerosis↗