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C Kurth

Publications and source records attributed to C Kurth.

22 records · Page 2Linked to original sources
PubMed1984

Chlorpromazine inhibits neutrophil chemotaxis beyond the chemotactic receptor-ligand interaction.

Phenothiazines depress Ca++-dependent neutrophil functions, perhaps by binding to calmodulin or perturbing membrane structure through hydrophobic interactions. We examined effects of chlorpromazine (CPZ) on the human polymorphonuclear neutrophil (PMN) chemotactic-oligopeptide receptor and PMN membrane fluidity. CPZ had a reversible, biphasic effect on PMN motility in the Boyden chamber (slight depression at 5 microM, enhancement at 10 microM, and dose-dependent inhibition at higher concentrations). Order of potency for inhibition of motility (trifluoperazine greater than CPZ greater than promethazine) was identical to that for both inhibition of superoxide (O-2) release and binding to calmodulin. CPZ nonspecifically altered the binding affinity of chemotactic fMet-Leu-[3H]Phe. As assessed with two spin-probes, PMN membrane fluidity was unaltered at CPZ concentrations that depressed PMN receptor-mediated chemotaxis and O-2 release. The data suggest that CPZ nonspecifically alters receptor affinity and depresses chemotaxis and O-2 release independently, without altering bulk membrane fluidity. We speculate that unidentified "post-receptor changes" at a common translocation step for functions tested account for the observed inhibition.

Chemotaxis, Leukocyte↗
PubMed1977

[Stenosis of the ureter opening in children. Etiology, clinical considerations, therapy (author's transl)].

In an analysis of 75 children with stenosis of the ureter opening, our results are compared to those in the literature (see in particular Tables 1 and 2). Abdominal pain stands out as the major symptom in more than half of the children. In our cases, intramural disturbances predominate in ca, 2/3 of cases, in the literature in about half of cases. The occurrence of extramural disturbances (accessory vessels, adhesions, higher opening of the ureter) occurs with equal frequency. The determining diagnostic procedure for stenosis of the ureter opening is an excretion urogram. Indications for a retrograde pyelogram and the performance of a micturation cystoureterogram are discussed. The operation of choice for stenosis of the ureter opening is the plastic operation of the renal pelvis of Anderson-Hynes, which has a success rate of at least 80%. Amoung our group of patients, primary nephrectomies were only seldom necessary.

Adolescent↗
PubMedDate not supplied

EEG spike detection with a Kohonen feature map.

Artificial neural networks are widely used for pattern recognition tasks. For spike detection in electroencephalography (EEG), feedforward networks trained by the backpropagation algorithm are preferred by most authors. Opposed to this, we examined the off-line spike detection abilities of a Kohonen feature map (KFM), which is different from feedforward networks in certain aspects. The EEG data for the training set were obtained from patients with intractable partial epilepsies of mesiotemporal (n=2) or extratemporal (n=2) origin. For each patient the training set for the KFM included the same patterns of background activity and artifacts as well as the typical individual spike patterns. Three different-sized networks were examined (15 x 15 cells, 25 x 25 cells, and 60 x 60 cells in the Kohonen layer). To investigate the quality of spike detection the results obtained with the KFM were compared with the findings of two board-certified electroencephalographers. Application of a threshold based on the partial invariance of spike recognition against translation of the EEG provided an average sensitivity and selectivity of 80.2% at crossover threshold (71%-86%) depending on the networksize and noise. Multichannel EEG processing in real time will be available soon. In conclusion, pattern-based automated spike detection with a KFM is a promising approach in clinical epileptology and seems to be at least as accurate as other more-established methods of spike detection.

Adult↗