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Marianne de Visser

Publications and source records attributed to Marianne de Visser.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of CMT1A and CMT2: similarities and differences.

To evaluate the clinical and electrophysiological similarities and differences between two large groups of patients with Charcot-Marie-Tooth disease, i.e. CMT1A and CMT2, we performed a post hoc comparison of clinical and electrophysiological data. Most CMT1A and CMT2 patients had the classical CMT phenotype. Age of onset was significantly later in CMT2. Total areflexia was present in approximately half of the CMT1A patients whereas it was rare in CMT2. Foot deformities and weakness of knee extensor and foot dorsal flexor muscles were more frequent in CMT1A. Median nerve motor nerve conduction velocities (MNCV) were always less than 38 m/s in CMT1A patients, whereas this was also the case in 16% of the CMT2 patients. Sensory nerve conduction velocities showed less overlap. In both CMT1A and CMT2 CMAP and SNAP amplitudes were often reduced or not obtainable in the legs. In CMT1A, SNAP amplitude was more reduced and SNAP duration more prolonged than in CMT2. We conclude that there are no robust clinical signs or symptoms that differentiate between CMT1A and CMT2 patients. Electrodiagnostical studies show a length-dependent motor and sensory axonal dysfunction in both CMT-types. Additional SNAP and SNCV evaluation may be helpful in focusing molecular genetic analysis in the occasional case of CMT2 showing slow motor nerve conduction velocities overlapping with CMT1A values. The reduction of CMAP and SNAP amplitudes in CMT1A is probably a combined effect of demyelination and axonal dysfunction.

Action Potentials↗
PubMed2006

Cardiac and pulmonary investigations in Bethlem myopathy.

BACKGROUND: Bethlem myopathy is considered a relatively mild neuromuscular disorder without significant cardiac and respiratory involvement. OBJECTIVE: To investigate cardiac and respiratory involvement in Bethlem myopathy. DESIGN: Cross-sectional study. SETTING: University hospitals. Patients Fifty patients with Bethlem myopathy from 26 families. INTERVENTIONS: Cardiac examinations, including electrocardiography and echocardiography (n = 37) and pulmonary investigations (n = 43). Holter monitoring was performed in 16 patients. MAIN OUTCOME MEASURES: Cardiac and respiratory abnormalities. RESULTS: Several cardiac abnormalities were found that were considered unrelated to the muscular disorder. Seven (16%) of 43 patients had a forced vital capacity less than 70% of the predicted value. One of 2 patients with a forced vital capacity less than 50% was also receiving respiratory support. All patients with compromised respiratory function were still ambulatory, and we found no significant correlation between the severity of arm weakness and the severity of respiratory muscle involvement. CONCLUSIONS: There is no evidence of cardiac involvement in Bethlem myopathy. Respiratory failure is part of the clinical spectrum and can occur in ambulatory patients.

Adult↗
PubMed2006

Axonal neuropathy with optic atrophy is caused by mutations in mitofusin 2.

OBJECTIVE: Charcot-Marie-Tooth (CMT) neuropathy with visual impairment due to optic atrophy has been designated as hereditary motor and sensory neuropathy type VI (HMSN VI). Reports of affected families have indicated autosomal dominant and recessive forms, but the genetic cause of this disease has remained elusive. METHODS: Here, we describe six HMSN VI families with a subacute onset of optic atrophy and subsequent slow recovery of visual acuity in 60% of the patients. Detailed clinical and genetic studies were performed. RESULTS: In each pedigree, we identified a unique mutation in the gene mitofusin 2 (MFN2). In three families, the MFN2 mutation occurred de novo; in two families the mutation was subsequently transmitted from father to son indicating autosomal dominant inheritance. INTERPRETATION: MFN2 is a mitochondrial membrane protein that was recently reported to cause axonal CMT type 2A. It is intriguing that MFN2 shows functional overlap with optic atrophy 1 (OPA1), the protein underlying the most common form of autosomal dominant optic atrophy, and mitochondrial encoded oxidative phosphorylation components as seen in Leber's hereditary optic atrophy. We conclude that autosomal dominant HMSN VI is caused by mutations in MFN2, emphasizing the important role of mitochondrial function for both optic atrophies and peripheral neuropathies.

Adolescent↗
PubMed2006

Variable pathogenic potentials of mutations located in the desmin alpha-helical domain.

Mutations in the desmin gene have been recognized as a cause of desminopathy, a familial or sporadic disorder characterized by skeletal muscle weakness, often associated with cardiomyopathy or respiratory insufficiency. Distinctive histopathologic features include aberrant intracytoplasmic accumulation of desmin (DES). We present here comparative phenotypic, molecular, and functional characteristics of four novel and three previously reported, but not fully characterized, desmin mutations localized in desmin alpha-helical domain. The results indicate that the c.638C>T (p.A213V), c.1178A>T (p.N393I), and to some extent the c.1078G>C (p.A360P) mutations exhibit pathogenic potentials only if combined with other mutations in desmin or other genes and should therefore be considered conditionally pathogenic. The c.1009G>C (p.A337P), c.1013T>G (p.L338R), c.1195G>T (p.D399Y), and c.1201G>A (p.E401K) mutations make desmin filaments dysfunctional and are capable of causing disease. The pathogenic potentials of desmin mutations correlate with the type and location of the disease-associated mutations in the relatively large and structurally and functionally complex desmin molecule. Mutations within the highly conserved alpha-helical structures are especially damaging since the integrity of the alpha-helix is critical for desmin filament assembly and stability.

Adult↗
PubMed2005

Dystrophin analysis in carriers of Duchenne and Becker muscular dystrophy.

Associations between clinical phenotype (muscle weakness, dilated cardiomyopathy) and dystrophin abnormalities in muscle tissue among definite carriers of Duchenne (DMD) and Becker muscular dystrophy (BMD) were investigated. No associations between dystrophin abnormalities and clinical variables in DMD/BMD carriers were found. Because 26% of nonmanifesting carriers have dystrophin-negative fibers, this might be used in suspected DMD/BMD carriers in whom DNA analysis fails to give an answer about their carrier risk.

Adolescent↗
PubMed2005

Inclusion body myositis. Clinical features and clinical course of the disease in 64 patients.

The clinical features of inclusion body myositis (IBM) were of minor importance in the design of consensus diagnostic criteria, mainly because of controversial views on the specificity of signs and symptoms, although some authors reported "typical" signs. To re-assess the clinical spectrum of IBM, a single investigator using a standard protocol studied a cohort of 64 patients cross-sectionally. Symptom onset was before the age of 50 years in 20% of cases. Only a few patients (14 %) started with weakness other than that of quadriceps, finger flexor or pharyngeal muscles. The sequence of power loss was erratic, but onset of symptoms with quadriceps weakness predicted an earlier onset of dysphagia in older patients (> or = 56 years) compared with younger ones (< 56 years) (p = 0.02). Despite widespread weakness patients had favourable scores on three commonly used function scales and they kept their employment. Complete wheel-chair dependency was rare (3 %). A dominant characteristic was the anatomical distribution of afflicted muscles: ventral extremity muscle groups were more affected than dorsal muscle groups and girdle muscles were least affected, the latter preserving postural stability. Ankylosis, especially in extension of the fingers,was frequently present. Together with the sparing of intrinsic hand muscles it was helpful in the preservation of many skillful movements. IBM has a unique distribution of muscle weakness. Ankylotic contractures are common. We feel that their joint impact on daily functioning is characteristic for the disease.

Age of Onset↗
PubMed2005

Early onset neuropathy in a compound form of Charcot-Marie-Tooth disease.

A 2-year-old boy presented with early-onset Charcot-Marie-Tooth disease (CMT). His parents had not been diagnosed previously with CMT, but on careful examination they showed clinical signs of CMT and reduced nerve conduction velocities. Genetic analysis identified the boy as a heterozygote for both a peripheral myelin protein 22 (PMP22) duplication and a mutation in the lipopolysaccharide-induced-tumour-necrosis-factor-alpha-factor (LITAF) gene, whereas each parent only had one mutated CMT gene. This suggests that LITAF mutations can severely affect the CMT phenotype caused by a PMP22 duplication.

Blotting, Southern↗
PubMed2004

Meta-analysis of clinical characteristics of 299 carriers of LMNA gene mutations: do lamin A/C mutations portend a high risk of sudden death?

This study evaluated common clinical characteristics of patients with lamin A/C gene mutations that cause either isolated dilated cardiomyopathy or dilated cardiomyopathy in association with skeletal muscular dystrophy. We pooled clinical data of all published carriers of lamin A/C gene mutations as cause of skeletal and/or cardiac muscle disease and reviewed ECG findings. Cardiac dysrhythmias were reported in 92% of patients after the age of 30 years; heart failure was reported in 64% after the age of 50. Sudden death was the most frequently reported mode of death (46%) in both the cardiac and the neuromuscular phenotype. Carriers of lamin A/C gene mutations often received a pacemaker (28%). However, this intervention did not alter the rate of sudden death. Review of the ECG findings typically showed a low amplitude P wave and prolongation of the PR interval with a narrow QRS complex. This meta-analysis suggests that cardiomyopathy due to lamin A/C gene mutations portends a high risk of sudden death, and that this risk does not differ between subjects with predominantly cardiac or neuromuscular disease. This implies then that all carriers of a lamin A/C gene mutation need to be carefully screened with particular emphasis also on tachyarrhythmias. Prospective studies are needed to evaluate risk stratification and proper treatment strategies.

Arrhythmias, Cardiac↗
PubMed2004

Mutations in the slow skeletal muscle fiber myosin heavy chain gene (MYH7) cause laing early-onset distal myopathy (MPD1).

We previously linked Laing-type early-onset autosomal dominant distal myopathy (MPD1) to a 22-cM region of chromosome 14. One candidate gene in the region, MYH7, which is mutated in cardiomyopathy and myosin storage myopathy, codes for the myosin heavy chain of type I skeletal muscle fibers and cardiac ventricles. We have identified five novel heterozygous mutations--Arg1500Pro, Lys1617del, Ala1663Pro, Leu1706Pro, and Lys1729del in exons 32, 34, 35, and 36 of MYH7--in six families with early-onset distal myopathy. All five mutations are predicted, by in silico analysis, to locally disrupt the ability of the myosin tail to form the coiled coil, which is its normal structure. These findings demonstrate that heterozygous mutations toward the 3' end of MYH7 cause Laing-type early-onset distal myopathy. MYH7 is the fourth distal-myopathy gene to have been identified.

Child↗
PubMed2004

Polymyositis: an ongoing discussion about a disease entity.

Since its first description more than a century ago, there has been much debate about the diagnostic entity polymyositis. Because initial observations were of individuals with dermatomyositis, it appeared that polymyositis was not possible without skin lesions. Distinctive clinical and histologic features of polymyositis were not established until the late 20th century. The identification of inclusion body myositis as a distinct entity has further refined nosographic classification.

Biopsy↗
PubMed2004

Postpolio syndrome.

Explore the source record for details and available documents.

History, 19th Century↗
PubMed2004

Clinical disease severity and axonal dysfunction in hereditary motor and sensory neuropathy Ia.

BACKGROUND: Hereditary motor and sensory neuropathy type Ia (HMSN Ia) is known as a primarily demyelinating peripheral nerve disease. Evidence is accumulating that axonal involvement determines the course of the disease process. METHODS: Fifty-one patients were investigated. Physical disability and impairments were scored. Nerve conduction velocities (NCVs) were used as indirect measures for myelination status and compound muscle/sensory nerve action potential (CMAP/SNAP) amplitudes served as indirect measures for axonal function. RESULTS: Median age was 39 years (range 6-69). Muscle weakness and sensory dysfunction was more severe in the legs than in the arms and distally more than proximally. However, more than 40% of the patients had proximal muscle weakness in the legs. Three point grip was used as representative of combined distal arm muscle groups. CMAP amplitude was the most important independent variable in a multiple linear regression model (forward selection) to explain the relation between three point grip strength and four different features, i. e., CMAP amplitude of the abductor pollicis brevis, median nerve MNCV, gender, and duration of signs and symptoms. The severity of axonal dysfunction was nerve length-dependent and was related to the myelination status. The mild physical disability due to both muscle weakness and sensory dysfunction was also related to axonal dysfunction. CONCLUSIONS: In HMSN Ia, clinical disease severity at the impairment and disability levels is related to the severity of axonal dysfunction. Our data support the hypothesis that the myelination status is one of the factors that determine the extent of axonal dysfunction later in life. Proximal weakness of the legs is encountered in a considerable proportion of our patients.

Action Potentials↗
PubMed2003

A randomized sequential trial of creatine in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal disease with no cure. In a transgenic mouse model of ALS, creatine monohydrate showed a promising increase in survival. We performed a double-blind, placebo-controlled, sequential clinical trial to assess the effect of creatine monohydrate on survival and disease progression in patients with ALS. Between June 2000 and December 2001, 175 patients with probable, probable-laboratory supported, or definite ALS were randomly assigned to receive either creatine monohydrate or placebo 10 gm daily. A sequential trial design was used with death, persistent assisted ventilation, or tracheostomy as primary end points. Secondary outcome measurements were rate of decline of isometric arm muscle strength, forced vital capacity, functional status, and quality of life. The trial was stopped when the null hypothesis of indifference was accepted. Creatine did not affect survival (cumulative survival probability of 0.70 in the creatine group vs 0.68 in the placebo group at 12 months, and 0.52 in the creatine group vs 0.47 in the placebo group at 16 months), or the rate of decline of functional measurements. Creatine intake did not cause important adverse reactions. This placebo-controlled trial did not find evidence of a beneficial effect of creatine monohydrate on survival or disease progression in patients with ALS.

Aged↗
PubMed2003

Quadriceps muscle strength and voluntary activation after polio.

Quadriceps strength, maximal anatomical cross-sectional area (CSA), maximal voluntary activation (MVA), and maximal relaxation rate (MRR) were studied in 48 subjects with a past history of polio, 26 with and 22 without postpoliomyelitis syndrome (PPS), and in 13 control subjects. It was also investigated whether, apart from CSA, MVA and MRR were determinants of muscle strength. Polio subjects had significantly less strength, CSA, and MRR in the more-affected quadriceps than control subjects. MVA was reduced in 18 polio subjects and normal in all controls. PPS subjects differed from non-PPS subjects only in that the MVA of the more-affected quadriceps was significantly lower. Both CSA and MVA were found to be associated with muscle strength. Quadriceps strength in polio subjects was dependent not only on muscle mass, but also on the ability to activate the muscles. Since impaired activation was more pronounced in PPS subjects, the new muscle weakness and functional decline in PPS may be due not only to a gradual loss of muscle fibers, but also to an increasing inability to activate the muscles.

Adult↗