Carcinom bei einem 3 jährigen Kinde

Ohne ZusammenfassungMit 2 Textabbildungen.     

Radiofrequency catheter ablation of two accessory pathways with different unidirectional conduction properties

Simultaneous occurrence of narrow and broad QRS complex tachycardias in patients with WPW syndrome usually indicates a macroreentry in an orthodromic atrioventricular reentry-tachycardia using the AV node as antegrade and the accessory pathway as retrograde conduction and vice versa in an antidromic circuit. We report on a 32-year-old woman with WPW syndrome presenting with both a narrow and a broad QRS complex tachycardia using two accessory pathways with different unidirectional conduction properties in combination of an exclusively antegrade conducting AV node. This case report describes conventional mapping techniques and ablation of this unusual entity of a WPW syndrome.     

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Use of an in vitro absorption model system for predicting sustained release of verapamil.

It is shown that it is possible to characterize sustained release formulations in vitro using not only dissolution data but also an absorption model system. The mean dissolution time (MDT) has been shown to be a suitable parameter for evaluating sustained release formulations in vitro. t1/2 and mean residence time (MRT) have been shown to be convenient pharmacokinetic parameters for characterizing sustained release formulations. For comparing in vitro and in vivo results the quotients MDT normal/MDT retard and MRT normal/MRT retard do seem to be useful.     

Clinico-electrophysiologic studies on the action of the anti-arrhythmic substance 3-carbethoxyamino-5-dimethylamino-acetyl-10,11-dihydro-5H- dibenz[b,f]azepine hydrochloride (Bonnecor, AWD 19-166, GS 015)

The effects of the new antiarrhythmic drug 3-carbethoxy-amino-5-dimethyl-amino-acetyl-iminodibenzyl-hydroc hlorid (Bonnecor) (B.) were investigated by means of clinical-electrophysiologic methods (His-bundle electrography, programmed electrical stimulation) in 11 patients with normal cardiac output and paroxysmal supraventricular tachycardias. In a maximal dosage of 0.24 mg/kg body mass. B. affects several compartments of the impulse initiation and conduction. B. has positive chronotropic actions on the sinus node automaticity, negative dromotropic effects on the sinu-atrial, intraatrial, AV nodal and intraventricular conduction and finally negative bathmotropic actions on the myocardium of the atria and ventricles. B. suppress the artificial induction of paroxysmal supraventricular tachycardias in patients with AV nodal reentry. These results help to recognize indications (supraventricular and ventricular premature beats or tachycardias) and contraindications (sick sinus syndrome, atrio-ventricular block of higher degreé and bifascicular blocks).     

Effect of 2-mercapto-ethanol on some brain biochemical characteristics and behavioural changes in the ageing CBA/Ca mice

Male CBA/Ca inbred mice were treated with a dose of 8 micrograms 2-mercapto-ethanol per animal per day in the drinking water from the age of 5 months onwards up to the age of 24 months. Dopamine release was greatly decreased in old animals in contrast to the elevation of dopamine release in the treated mice. Similarly, an elevated malondialdehyde content in brain homogenates was also observed in the aged treated animals compared with their controls. No essential differences were observed in locomotor activity and learning between treated an control mice.     

Mechanism of the effect of electrostimulation during the interruption of tachycardial arrhythmias]

With the help of three individual electrocariograpic observations which were collected at the end of tachycardiac disturbances of rhythm by electrostimulation, the author enters the mechanism of action of this form of the cardiac electrotherapy. From this its indication and the most rational practical approach are derived.     

A model system that predicts effective half-life for radiolabeled antibody therapy

Radiolabeled antibodies to tumor associated proteins localize in both experimental and clinical cancers. In the therapeutic applications of radiolabeled antibody, tumor effective half-life (composite of biological and physical half-lives), along with the concentration of isotope deposited and energies of the isotope used, determine the tumor dose. Antibodies directed against the same antigenic specificity but derived from different species have varied tumor and whole body effective half-lives and as a result, achieve different tumor doses. In vitro testing does not evaluate the in vivo differences in effective half-life that affect tumor dose. We have developed an animal model to evaluate the effective half-life and biodistribution of radiolabeled immunoglobulin (IgG) from diverse species. To determine the relevance of such a model, the effective half-lives and tissue distributions of the different immunoglobulins in the model were compared to those obtained from the clinical program using the same radiolabeled antibody preparations. In both the experimental model and in the clinical trials, radiolabeled immunospecific and normal IgG derived from monkey, rabbit, and porcine sources had the longest effective half-lives, goat and sheep had intermediate effective half-lives, and chicken and turkey had the shortest effective half-lives. Prescreening of bovine and baboon normal IgG predict long half-lives and similar organ distributions. These species have been immunized for clinical use. Bovine IgG has a long clinical half-life and has been added to our other successful antibodies. Baboon IgG is now ready for clinical testing. The value of this model system is that it appears to be an effective in vivo preclinical screen for tumor effective half-life of antibodies and IgG from diverse species, thus guiding potential clinical use.