Search PubMed⌕ Search

Biomedical subjects

C Meier

Publications and source records attributed to C Meier.

At least 181 records · Page 10Linked to original sources
PubMed1983

Hereditary motor sensory neuropathies in childhood.

Clinical data on 24 patients with hereditary motor sensory neuropathies, with onset in the paediatric period, and of their relatives, is reported. Electrophysiological studies were done in all patients and in 15 relatives. The patients were divided into two groups (Types I and II) and their hereditary trait was determined. In 11 patients a sural nerve biopsy was performed and revealed different patterns of histological alterations. The nerve biopsy always confirmed the value of conduction velocity in distinguishing between Types I and II. A genetic discordance was observed, both in regard to the phenotype and the conduction velocity, and there was increased slowing of the conduction velocity as individuals grew older. Thus the classification of these disorders in childhood can be particularly difficult. The rôle of sural nerve biopsy is discussed.

Adolescent↗
PubMed1983

Demyelinating neuropathy and monoclonal IgM antibody to myelin-associated glycoprotein.

We studied a patient with demyelinating neuropathy and monoclonal IgM kappa antibody to the major myelin-associated glycoprotein (MAG). Binding of this monoclonal antibody to the myelin antigen was demonstrated by immunoelectroblot. Binding to MAG seemed to be specific, because it was completely inhibited by MAG isolated from human myelin. Immunostaining was observed with MAG from CNS and peripheral nervous system myelin.

Antibodies, Monoclonal↗
PubMed1983

[Long-term EEG course study in patients with Creutzfeldt-Jacob disease].

In a patient with Creutzfeldt-Jakob disease subsequently confirmed by autopsy, 34 EEGs were carried out in a 14 months period. 6 weeks after the beginning of the prodromal stage of the disease a triphasic, periodic activity was recorded for the first time. This activity was maximally in evidence at 15th week. A synchrony occurring between repetitive complexes and myoclonic jerks could between repetitive complexes and myoclonic jerks could only be observed during one recording. From the 5th month onwards the intensity of the periodic EEG pattern, seen longitudinally, gradually decreased. In the time-span from the 10th to the 13th month considerable fluctuations of periodic activity were found, this during the course of one as well as between different EEG recordings. These could reach from a pronounced typical pattern to complete disappearance of periodic triphasic complexes. As possible causes for these fluctuations, we discussed a variable driving by the subcortical pacemaker as well as a decreased capability of cerebral cortex--gradually loosing so many neurons--to react to subcortical stimuli. From the 14th month onwards the periodic activity no longer could be put in evidence. In the last EEG recorded 3 days before death isoelectric periods alternated with paroxysmal delta waves respectively sharp and slow wave complexes.

Cerebral Cortex↗
PubMed1982

Non-competitive interaction between normorphine and calcium on the release of noradrenaline.

The interaction between calcium and magnesium or normorphine was studied on the electrically evoked outflow of previously incorporated [3H]noradrenaline in the isolated mouse vas deferens. The stimulation-evoked outflow of [3H]noradrenaline increased with increasing concentrations of Ca2+ ions in the medium. Mg2+ counteracted the effect of Ca2+ in a manner compatible with competitive antagonism. In contrast, normorphine interfered with the effect of Ca2+ non-competitively, thus suggesting that its mode of action differed from that of Mg2+.

Animals↗
PubMed1982

Hereditary neuropathy with liability to pressure palsies. Report of two families and review of the literature.

Clinical, neurophysiological and pathological investigations were carried out in 11 affected members of 2 families with hereditary neuropathy with liability to pressure palsies (HNPP). The observations were related to findings in 261 cases of 47 families published in the literature. It was concluded that HNPP is a nosological entity characterized by the following diagnostic criteria: (1) an autosomal dominant inheritance; (2) the clinical presentation of a recurrent mononeuropathy simplex or multiplex, frequently related to an inadequate trauma to peripheral nerves; (3) a significant slowing of motor and sensory conduction velocity in clinically affected, but also in clinically unaffected nerves; (4) characteristic morphological findings in sural nerve biopsy featuring "tomaculous" swellings of myelin sheaths, transnodal myelination and segmental demyelination. The pathogenesis of HNPP is not clear. Hypothetical explanations of the pathogenesis of HNPP are discussed.

Adult↗
PubMed1982

[Hereditary motor sensory neuropathies].

The descriptive term "hereditary motor sensory neuropathy (HMSN)" includes a group of disorders of different nosology which besides heredity show a progressive distal symmetrical motor sensory neuropathy as a common clinical feature. The etiology of these disorders is probably different. According to electrophysiological and morphological findings two major types of HMSN can be distinguished from each other: 1. The neural type (HMSN, type I) is characterized by axonal degeneration, segmental demyelination and hypertrophic changes. The nerve conduction velocity in this type is significantly slowed. 2. The neuronal type (HMSN, type II) shows axonal degeneration with secondary segmental demyelination and no hypertrophic nerve changes. The nerve conduction velocity in these cases is normal or insignificantly decreased. This paper includes a historical review and a detailed description of the clinical, electrophysiological and morphological findings of the two major types of HMSN. The current classifications of HMSN are cited and critically discussed.

Electromyography↗
PubMed1981

Quantitation of DNase I sensitivity in Xenopus chromatin containing active and inactive globin, albumin and vitellogenin genes.

The disappearance of defined restriction fragments of the beta 1-globin, an albumin and the A1 vitellogenin gene was quantitated after DNase I digestion and expressed by a sensitivity factor defined by a mathematical model. Analysis of naked DNA showed that the gene fragments have similar but not identical sensitivity factors. DNase I digestion of chromatin revealed for the same gene fragments sensitivity factors differing over a much wilder range. This is correlated to the activity of the genes analyzed: the beta 1-globin gene fragment is more sensitive to DNase I in chromatin of erythrocytes compared to hepatocytes whereas the albumin gene fragment is more sensitive to DNase I in chromatin of hepatocytes. The A1 vitellogenin gene has the same DNase I sensitivity in both cell types. Comparing the DNase I sensitivity of the three genes in their inactive state we suggest that different chromatin conformations may exist for inactive genes.

Albumins↗
PubMed1981

Peripheral and central conduction times in hereditary pressure-sensitive neuropathy.

Seven members of a family with histologically proven hereditary pressure-sensitive neuropathy (HPSN) agreed to be examine clinically and electrophysiologically. A sural nerve biopsy specimen taken from the propositus who suffered from a partial brachial plexus palsy showed typical 'sausage-like' myelin sheath thickenings reflecting a failure of axon-adjusted myelination. Reduced motor and sensory conduction velocities involving several nerves were found in the four family members with clinical signs of HPSN. In addition, central conduction times in the auditory and somatosensory pathways were determined measuring the interwave latency I-V in brainstem auditory-evoked potentials and the interpeak latency N14-N20 in median nerve sensory-evoked potentials. Central conduction times in both afferent systems were within normal limits. The absolute delay of peak N14 and N20 in median and P40 in tibial nerve-evoked potentials was probably due to an impaired conduction in the peripheral branch of the bipolar ganglion cell. Whether the central axon branch in the dorsal columns was also involved could not be decided.

Adult↗
PubMed1981

Neuromyopathy and vitamin E deficiency in man.

A 12-year-old boy, born of a consanguineous marriage, had ataxia, sensory neuropathy, generalized muscle hypotrophy and a lower serum vitamin E level. Two of his relatives had died of a clinically similar disorder in their late adolescence. Morphologically, his striated muscle fibers and Schwann cells of his sural nerve contained numerous autofluorescent acid phosphatase-positive lipopigments which, by electron microscopy, consisted of a finely granular matrix surrounded by a trilaminar membrane. These lysosomal lipopigments were similar to those observed in muscle fibers of a patient afflicted with abeta-lipoproteinemia. They probably represent the morphological sequelae of long-standing vitamin E deficiency in this child, the extract origin of which has not been fully elucidated.

Child↗
PubMed1981

[Measurement of systolic time intervals by echocardiographic and conventional methods (author's transl)].

In 25 patients the systolic time intervals were simultaneously measured by echocardiography and by the conventional method using the ECG, phonocardiogram and indirect carotid pulse tracing. Beat-to-beat-analysis showed no significant difference for QS2 (367.1 +/- 26.7 ms vs. 367.9 +/- 26.5 ms). In contrast, the LVET measured by echocardiography was significantly longer than the LVET taken from the indirect carotid pulse tracing (275.3 +/- 26.3 ms vs. 266.2 +/- 25.9 ms, p less than 0.001). As a consequence, the echocardiographic PEP was significantly shorter than the conventionally measured PEP (91.3 +/- 18.0 ms vs 100.9 +/- 22.7 ms, p less than 0.001). Furthermore, both methods showed the weakest correlation for the ratio PEP/LVET. We conclude that STI can be reproducibly measured by echocardiography, which will lead to significantly different values for the STI compared to those measured by the conventional method.

Adolescent↗