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H J Kühn

Publications and source records attributed to H J Kühn.

At least 19 recordsLinked to original sources
PubMed2004

Vacuum-ultraviolet beam array generation by flat micro-optical structures.

Micro-optical structures for VUV laser beam shaping and wave-front sensing were manufactured by thin-film deposition onto CaF2 and transfer by etching. Arrays of Bessel-like F2 laser beams at a wavelength of 157 nm with extremely small conical angles were generated by microaxicon lenses. Beam propagation was studied in simulations and experiments. Apodization by absorbing layers is proposed for beam cleaning.

Journal Article↗
PubMed2003

Investigation of fine-motor disturbances in Wilson's disease.

Patients suffering from Wilson's disease (WD) can be divided into two main subgroups: neurologic and nonneurologic WD. We measured passive and active fine-motor abilities of 37 WD patients and 24 randomly selected volunteers. The measurement was based on a standardized test set in a defined environment for detection of disturbed finemotor control. The set contains 5 tests comprising rest tremor, postural tremor, target tapping, forefinger tapping and spiral painting, reflecting different aspects of movement disorders. The tests showed significant differences between neurologic WD and volunteers, especially for tasks defining active control. In neurologic WD we found no differences between subgroups whereas for non-neurologic WD we often detected slight movement disorders. The detected movement disorders cam be interpreted as persistent disorders after long-term therapy.

Adult↗
PubMed2001

Differential alteration of the nigrostriatal dopaminergic system in Wilson's disease investigated with [123I]ss-CIT and high-resolution SPET.

Wilson's disease (WD) is a copper deposition disorder which can result in a number of extrapyramidal motoric symptoms such as parkinsonism. Therefore, this study was carried out to investigate, for the first time, nigrostriatal dopaminergic function in WD in relation to different courses and severity of the disease. Using high-resolution single-photon emission tomography (SPET) after administration of 2ss-carbomethoxy-3ss-(4[123I]iodophenyl)tropane ([123I]ss-CIT), striatal dopamine transporters (DAT) were imaged in 43 WD patients and a control group of ten subjects. From the SPET images, specific [123I]ss-CIT binding ratios were obtained for the caudate heads, putamina and entire corpus striatum. In addition, to evaluate a putative dissociation between the caudate and putaminal [123I]ss-CIT binding ratios, the ratio between these binding ratios was calculated (CA/PU ratio). The SPET data were compared with clinical data on the course of the disease (CD), the severity of neurological symptoms and the degree of hepatic alteration. Whereas the specific regional [123I]ss-CIT binding ratios in patients with asymptomatic/hepatic CD did not differ from those in the control group (e.g. striatal ratios: 13.4+/-3.0 vs 11.7+/-2.8), in patients with neurological CD the ratios were significantly reduced for all striatal substructures (P=0.003 after one-factor ANOVA). For the different subgroups a tendency was detected towards a stepwise decrease in the specific [123I]ss-CIT binding ratios from pseudo-sclerosis CD (9.4+/-2.3), through pseudo-parkinsonian CD (9.1+/-2.1) to arrhythmic-hyperkinetic CD (8.5+/-1.6). However, these group differences reached significance only for the comparison with asymptomatic/hepatic CD (P=0.02). The CA/PU ratio was significantly higher in WD than in the control group (1.30+/-0.19 vs 1.11+/-0.08; P=0.003). Severity of neurological symptoms was significantly correlated with all specific regional [123I]ss-CIT binding ratios (r=-0.49 to -0.57). For degree of liver alteration, significant correlations were obtained with the putaminal binding ratio (r=-0.37) and the CA/PU ratio (r=0.44). From these results is concluded that in WD the nigrostriatal dopaminergic function is compromised to varying extents. The degree of this presynaptic alteration of dopaminergic neurotransmission depends on the clinical course and severity of this copper deposition brain disorder and also varies in the different striatal substructures.

Adult↗
PubMed2001

High prevalence of the H1069Q mutation in East German patients with Wilson disease: rapid detection of mutations by limited sequencing and phenotype-genotype analysis.

BACKGROUND/AIMS: Wilson disease is caused by a large number of different mutations in the ATP7B gene. Wilson disease patients from a homogeneous ethnical background (Saxonia) were studied for distribution and phenotypes of ATP7B mutations. METHODS: Eighty-two patients were analyzed. The H1069Q mutation was assayed by a polymerase chain reaction-based restriction fragment length polymorphism test. Exons 8 and 15 were sequenced in all, and the entire gene in 30, non-H1069Q-homozygotes. RESULTS: Four novel and 12 known mutations were found. Thirty-two (39%) Wilson disease patients were homozygous and 39 (48%) heterozygous for the H1069Q mutation (allele frequency 63%). Together with sequence analysis of exons 8 and 15 mutations in both alleles were identified in 65% of patients. Only one patient had both mutations at other locations. In H1069Q homozygotes symptoms started later (21.3+/-7.2 years) than in H1069Q compound heterozygotes (14.6+/-5.8, P<0.001) or H1069Q negatives (10+/-4.4, P<0.001), and they had more frequently neurologic symptoms (93 vs. 47%, P<0.001) and Kayser-Fleischer rings (82 vs. 51%, P<0.001). Mutation status did not correlate with liver biopsy findings, serum ceruloplasmin levels or (64)Cu-assay results. CONCLUSIONS: In spite of many known ATP7B mutations, only few occur in this homogeneous population. Limited genetic testing is useful to confirm Wilson disease in this population.

Adenosine Triphosphatases↗
PubMed1997

Serum neuron-specific enolase levels do not increase after electroconvulsive therapy.

BACKGROUND: Cognitive disorders occurring after electroconvulsive therapy (ECT) are regarded as an expression of brain damage, despite computed tomography (CT) and magnetic resonance imaging (MRI) showing no signs of structural brain damage. Serum neuron-specific enolase (NSE) is a sensitive marker of neuronal damage (i.e., after stroke or cardiac arrest). The objective of this study was to investigate whether ECT leads to a rise in the serum NSE level as an expression of neuronal damage. METHODS: We investigated seven patients (four women, three men; mean age 6212 years) with major depressive disorder, who were treated with ECT for the first time. ECT was administered every 2 days, three times a week under standard conditions (anaesthesia: thiopental, succinylcholine, 100% oxygen, unilateral ECT, seizure duration more than 20 s). Blood samples were drawn at the following times. For the first ECT: 15 and 1 min before ECT, and 1, 5, 10, 15, 20, 25, 30, 45, 60, 75, 90, 105, 120 min, and 8, 12, 24 h after ECT. For all subsequent ECT: 1 min before and 4 h after every ECT. Serum NSE was measured by means of enzyme immunoassay (Cobas Core NSE, EIA, Hoffmann-La Roche). RESULTS: On average, each patient underwent ECT 10 times (range 5-20). In the first ECT there was no difference in serum NSE levels before and at all times following ECT. A comparison of serum NSE levels before and after each subsequent bout of ECT revealed no differences. Moreover, comparing the baseline serum NSE levels (before the first ECT) with the values after final ECT showed no differences either. CONCLUSION: ECT did not increase serum NSE values, indicating that electroconvulsive therapy does not cause neuronal damage.

Aged↗
PubMed1991

Mode of action of triethylenetetramine dihydrochloride on copper metabolism in Wilson's disease.

The drug of choice for the initial treatment of "decoppering" in Wilson's disease, an inherited disorder of copper metabolism, is the chelating agent D-penicillamine. In the case of harmful side-effects an alternative drug is triethylenetetramine dihydrocholoride (trien or trientine). Using the 24-h-urine excretion of copper and the oral copper loading test with copper-64, a double function for trien was found: trien increases the urine copper excretion and decreases the intestinal copper absorption respectively.

Adult↗
PubMed1990

[Wilson's disease in East Germany: in retrospect and perspectives -- an evaluation].

Wilson's disease is an autosomal recessive inherited metabolic disorder due to a disturbance of copper metabolism. Although the primary genetic defect is not known a longlife treatment is necessary for establishing a negative copper balance by removing the metal of the abnormal body stores. Experiences in handling with this disease in our country over a period of 20 years are reported. Especially epidemiologic findings, the diagnostic procedures and the strategies in therapeutic regimes are discussed. Future advances in genomic diagnostics are mentioned.

Adolescent↗
PubMed1989

Long-term care and management of Wilson's disease in the GDR.

Diagnosis, long-term management and family investigations of Wilson's disease are provided by selected clinical institutions in the GDR. From 187 patients detected since 1949, 111 are alive. In spite of the principal effectiveness of penicillamine treatment, confirmed by the disappearance of most of the central nervous system symptoms and successful professional rehabilitation of many patients, insufficient therapeutic discipline, psychosocial disturbances and penicillamine side-effects forcing its substitution by zinc or triethylenetetramine dihydrochloride in 14 cases need our further attention.

Adaptation, Psychological↗
PubMed1989

[Nosologic evaluation of oculopharyngeal myopathic syndromes].

Three patients with oculopharyngeal involvement of neuromuscular origin are presented: one patient suffering from an oculopharyngeal neuromuscular disease (developing an oculopharyngeal muscular dystrophy?) and two patients representing a neuromuscular mitochondriopathy. There is no evidence that the oculopharyngeal myopathy and neuromuscular disease, respectively, are the same, despite the simularity of the syndrome. The different clinico-pathological types of oculopharyngeal syndromes are discussed. Following-up the development of further manifestations of the oculopharyngeal syndrome can helf classifying them.

Adolescent↗
PubMed1989

[Secondary muscular carnitine deficiency following immunosuppressive treatment].

Carnitine deficiency syndromes can be classified into two groups: primary carnitine deficiency and secondary carnitine deficiency syndromes. A lipid storage myopathy with carnitine deficiency following an immunosuppressive therapy is described in a young man suffering from a possible polymyositis. After treatment with L-carnitine both biochemical and morphological features recovered. A secondary carnitine deficiency syndrome due to an immunosuppressive therapy is supposed.

Adult↗
PubMed1989

[The carnitine level of the umbilical cord blood in relation to the course of labor].

Total and free carnitine were analyzed in cord blood of 24 newborn babies, with uncomplicated delivery, and 12 neonates with protacted labour. At birth, the mean neonatal carnitine value (total 33.7 +/- 10.1; free 23.5 +/- 7.5 mumol/l) was lower than the mean adult value (60.0 +/- 10.0 and 50.5 +/- 7.3, resp.). The carnitine values in the group with protracted labour increase slowly with duration of delivery. In our opinion carnitine values of neonates are not suitable for diagnosis of systemic carnitine deficiency syndrome.

Carnitine↗
PubMed1986

Myopathy with mitochondrial abnormalities and rimmed vacuoles.

A man of 44 years suffering from an exercise-induced neuromuscular disease with mitochondrial abnormalities and rimmed vacuoles is reported. The mitochondrial abnormalities and rimmed vacuoles (autophagic vacuoles) are interpreted as sequential changes of the same pathogenetic process depending on the degree of energy deficiency.

Extremities↗
PubMed1984

[Detection, genetic counseling and phenotype prevention of Duchenne muscular dystrophy].

Literature data and the own ascertainment of Duchenne muscular dystrophy cases concentrated on the Leipzig county confirm the necessity of early diagnosis and of central registration, search for female carries and genetic counselling. A newborn screening is supported provided that its organization will be practicable. About 12% of Duchenne cases are secondary affections of brothers. It should be possible to prevent one third of all cases by means of counselling also of the female relatives of the mothers. The repeated estimation of serum creatinkinase activity, completed by electromyography, has the greatest practical importance for the identification of heterozygous carriers. For the genetic counselling of definite carriers and women at risk it is possible only to recommend intrauterine sex prediction and the selective abortion of male fetuses.

Adolescent↗