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Biomedical subjects

S Zierz

Publications and source records attributed to S Zierz.

At least 145 records · Page 8Linked to original sources
PubMed1990

[Abnormal regulation of carnitine palmitoyltransferase in monozygotic twins as the cause of rhabdomyolysis].

Severe myalgias, accompanied by reddish brown discolouration of the urine, occurred after strenuous exercise (all-day hockey competition) in a 21-year-old competitive athlete. Creatine kinase concentration was 1914 U/l, but there were no abnormal physical findings. The myalgias disappeared within three days. A biopsy from the lateral vastus muscle in the patient and his monozygotic twin brother showed normal total activity of carnitine palmitoyltransferase (CPT), but residual activity after inhibition with malonyl-CoA and Triton X-100 was clearly reduced in both brothers. Thus the illness was a rhabdomyolysis due to a, presumably inherited, abnormal regulation of CPT. The symptoms can be precipitated by fasting, marked physical exertion, cold or viral infection.

Acyltransferases↗
PubMed1990

Activation of epileptic foci by transcranial magnetic stimulation: effects on secretion of prolactin and luteinizing hormone.

Transient elevation of serum levels of prolactin has been observed following several types of epileptic seizures and after electrical stimulation of limbic temporal lobe structures via implanted electrodes. Transcranial magnetic stimulation has been found to selectively induce epileptiform afterdischarges in the epileptic focus of candidates for epilepsy surgery who suffered from temporal lobe epilepsy. Lateralized serial transcranial magnetic stimulation was therefore used and serum levels of prolactin or luteinizing hormone were measured to find if it could be used as a non-invasive diagnostic tool. The investigation was performed on six patients and five healthy volunteers. In the patients the induction of epileptiform potentials was continuously monitored via subdural electrodes. A transient surge of prolactin and luteinizing hormone was found in only one patient, in whom a complex partial seizure was induced. Thus, transcranial magnetic stimulation appeared not to be helpful for the lateralization of the (primary) epileptic focus during presurgical evaluation.

Adult↗
PubMed1990

Mitochondrial myopathies: divergences of genetic deletions, biochemical defects and the clinical syndromes.

Genomic Southern analysis of muscle mitochondrial (mt) DNA from 16 patients with mitochondrial myopathies was performed; 14 of 16 patients had chronic progressive external ophthalmoplegia (CPEO), while 2 patients had mitochondrial myopathies without CPEO. Eleven patients with CPEO, including 5 who exhibited the complete triad of symptoms characteristic of the Kearns-Sayre syndrome (i.e. CPEO, retinal degeneration and heart block) had heteroplasmic mtDNA with deletions ranging from 2.0 to 8.0 kb in length. There was no clear-cut correlation between the size and location of the deletions, on the one hand, and the histochemical and biochemical data or the severity of the disease, on the other.

Adolescent↗
PubMed1990

Exogenous coenzyme Q (coq) fails to increase coq in skeletal muscle of two patients with mitochondrial myopathies.

Recently, several studies were published on therapy with coenzyme Q (CoQ) in patients with mitochondrial myopathies without biochemically established muscular deficiency of CoQ. Two patients with mitochondrial myopathies presenting as oculocraniosomatic syndromes were treated with coenzyme Q (CoQ). The muscle biopsy of both patients showed ragged-red fibers and single muscle fibers without histochemical reaction for cytochrome c oxidase. Biochemical analysis revealed normal activities of the respiratory chain complexes in muscle and normal levels of CoQ in serum and muscle. After one year of treatment CoQ in serum of both patients had increased 1.4-fold and 2.0-fold, respectively. In muscle, however, there was no increase of CoQ in either patient. In both patients the activities of citrate synthase and of the respiratory chain complexes I + III and IV, and in 1 patient also of complex II + III, were lower in the second biopsy compared with the first biopsy. In both patients there was no improvement of maximal isometric muscle strength assessed by a quantitative electronic strain gauge. The exercise-induced pathological rise of lactate in 1 patient remained essentially unchanged during therapy. The data indicate that orally administered CoQ fails to increase total CoQ in muscle of patients with mitochondrial myopathies but without muscular CoQ deficiency.

Administration, Oral↗
PubMed1990

Mutations of the mitochondrial DNA: the contribution of DNA techniques to the diagnosis of mitochondrial encephalomyopathies.

We performed restriction analysis and Southern blotting of the muscle mitochondrial DNA from 34 patients suffering from different myopathies. In 13/21 patients with chronic progressive external ophthalmoplegia the muscle mitochondrial DNA was shown to be heteroplasmic. Further mapping by use of several restriction enzymes yielded large deletions in muscles from 10/13 chronic progressive external ophthalmoplegia patients. Most of the deletions spanned large parts of the mitochondrial genome, leading to loss of mitochondrial genes encoding several subunits of the respiratory chain complexes I (NADH-dehydrogenase), IV (cytochrome c oxidase) and V (ATP-synthetase), as well as of several tRNAs. Comparison of the mapping data with the histochemical and biochemical results did not provide a clear correlation between the location of the mitochondrial genetic defects and the functional deficiencies of the affected respiratory chain complexes. In the majority of patients with chronic progressive external ophthalmoplegia, but without a family history of the disease, restriction analysis reveals large mutations of the mitochondrial genome, while other methods are necessary for the localization of defects in all cases with maternal transmission of the disease. The same holds true for all other kinds of mitochondrial myopathies based on defects within the nuclear DNA or on derangements of the "cross-talk" between the nuclear and the mitochondrial genomes.

Adult↗
PubMed1990

HMPAO-SPECT imaging resembling Alzheimer-type dementia in mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS).

Single-photon emission computed tomography (SPECT) of the brain using hexamethyl propylene amine oxime (HMPAO) was performed in a 37-year-old patient suffering from mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). Reduced blood flow was observed bilaterally in the parieto-occipital regions (resembling Alzheimer type dementia) and in the right parietal lobe.

Acidosis, Lactic↗
PubMed1990

[Indications for pacemaker therapy in ophthalmoplegia plus and Kearns-Sayre syndrome].

Mitochondrial myopathies can affect the skeletal muscle, the central or peripheral nervous system, and they may be associated with chronic progressive external ophthalmoplegia (CPEO). In 7/29 patients with mitochondrial myopathies and CPEO a cardiac involvement (Kearns-Sayre syndrome) was found: incomplete right bundle branch block (n = 1), right bundle branch block (n = 1), left anterior fascicular block and right bundle branch block (n = 2), complete atrioventricular block (n = 3); congestive cardiac failure (ejection fraction 40%) (n = 2); 3/10 patients had prolonged infranodal conduction on His-bundle electrography (HV-interval 60 ms). The cardiac involvement in ophthalmoplegia plus is characterized by progressive impairment of fascicular conduction. The need for prophylactic pacemaker implantation appears to exist in patients with bifascicular block and prolonged His-ventricle conduction.

Adolescent↗
PubMed1989

Coenzyme Q in serum and muscle of 5 patients with Kearns-Sayre syndrome and 12 patients with ophthalmoplegia plus.

Coenzyme Q10 (CoQ) was measured in serum and muscle of 17 patients with ophthalmoplegia plus (including 5 patients with Kearns-Sayre syndrome), in muscle of 9 patients with neurogenic atrophies, 5 patients with myositis, and 5 patients with progressive muscular dystrophies (including 1 patient with oculopharyngeal dystrophy), and in serum and muscle of normal controls. CoQ was markedly decreased in serum and muscle of 1 patient with Kearns-Sayre syndrome and treatment with CoQ resulted in a significant clinical improvement. The other 4 patients with Kearns-Sayre syndrome and the patients with ophthalmoplegia plus exhibited normal concentrations of CoQ in serum and muscle. CoQ levels in muscle of patients with progressive muscular dystrophies, myositis or neurogenic atrophies were within the normal range. Concentrations of CoQ in serum and muscle of normal controls were independent of age and showed no sex difference. The data indicate that CoQ deficiency might be the specific cause of mitochondrial encephalomyopathy in 1 patient but it was not the underlying defect common to all cases with Kearns-Sayre syndrome and ophthalmoplegia plus, although the possibility of a focal CoQ deficiency affecting only single muscle fibres cannot be excluded.

Adolescent↗
PubMed1989

Partial deficiency of complexes I and IV of the mitochondrial respiratory chain in skeletal muscle of two patients with mitochondrial myopathy.

Respiratory chain enzymes were studied in isolated mitochondria of two patients with mitochondrial myopathy. Both patients had been suffering from chronic progressive external ophthalmoplegia and abnormal muscular fatigability since late childhood. One of the patients exhibited the complete triad of symptoms characteristic of Kearns-Sayre syndrome. Venous lactate levels at rest and during minimal exercise were increased in both patients. Histochemical examination of muscle revealed ragged red fibres and intermingled fibres negative for cytochrome c oxidase. Biochemical studies showed decreased activities of complex I and complex IV of the respiratory chain in both patients. Reduced minus oxidized spectra of mitochondrial cytochromes revealed a decreased content of cytochrome aa3 in only one patient, but a normal content in the other. A combined deficiency of complexes I and IV in muscle might either be due to a deficiency of a single subunit common to both complexes or to a coincidental deficiency of both complexes expressed either in the same or in different fibres.

Adult↗
PubMed1989

[Adrenoleukodystrophy and adrenomyeloneuropathy--clinical spectrum, pathobiochemical aspects, diagnosis and therapy].

Adrenoleukodystrophy (ALD) is characterized by adrenal cortical insufficiency and progressive demyelination of the central nervous system with lethal outcome in childhood. Adrenomyeloneuropathy (AMN) represents a clinical variant of ALD with later manifestation during adolescence. The neurological symptoms of this form are slowly progressive spastic paraparesis and peripheral neuropathy. Other intermediate forms, which might be classified as adrenoleukomyeloneuropathy (ALMN), possibly represent an overlap of the two conditions. Heterozygote carriers of the X-linked disease may also show neurological symptoms, such as spastic paraparesis and peripheral neuropathy. Biochemically, all these X-linked forms of ALD/AMN are characterized by an accumulation of very-long-chain fatty acids in various tissues and body fluids indicating an impaired peroxisomal metabolism. In this study two families with ALD are presented. The two forms of ALD and AMN were observed in different members of the families including a heterozygote female carrier with neurological symptoms. The different clinical syndromes, the biochemical and genetic basis, and new therapeutical strategies are discussed.

Adrenoleukodystrophy↗