[Basic tenets for quality circles in North Rhine Medical Service of Public Health Insurance]. / Grundsätze für Qualitätszirkel beim MDK Nordrhein.

The Medical Advisory Service of the Health Insurance in the area of the Northern Rhine (MDK Nordrhein) has set up an internal concept for quality management since 1998. This concept includes the installation and performance of quality circles. Staff members were internally qualified as "presenters". They worked out principles for quality circles of the MDK North Rhine which were implemented as binding basic rules by the managing conference of the MDK. The principles will be presented in detail.

Paradoxical embolism and aortic occlusion: a case report.

This is the case report of a 45-year-old woman who sustained a left popliteal artery embolism. Ten days after popliteal embolectomy, she developed sudden occlusion of the distal aorta. She required a bifemoral embolectomy. Transesophageal echocardiogram demonstrated an atrial septal aneurysm and a septal defect with a right to left shunt. A venogram showed deep venous thrombosis in the right leg as the potential source of the embolism. Paradoxical embolization should be considered when ever an unexplained arterial occlusion occurs, especially in younger patients.

The effects of metoclopramide and cloxacepride on human mast cells from adenoidal tissues.

Cloxacepride is an amide of the dopamine antagonist metoclopramide and has been reported to possess oral antiallergic properties in the rat PCA model. Both substances have now been tested in isolated mast cell preparations from human adenoidal tissues to determine whether any therapeutic antiallergic potential in man could be expected. Metoclopramide at concentrations 10(-5)-10(-3) M had no inhibitory effect but instead enhanced Con A-induced histamine release at concentrations greater than 10(-4) M. Cloxacepride at concentrations 10(-5)-10(-4) M significantly inhibited Con A-induced histamine release. This inhibitory effect was not diminished by increasing the preincubation time for up to 30 min. In contrast, cloxacepride concentrations greater than 4 x 10(-5) M caused a substantial histamine release. This effect could not be alleviated by an increase in the number of mast cells per sample. These results then suggest a very narrow range of therapeutic potential for cloxacepride.

Seasonal variation of mast cell function in human adenoid tissues.

The number of mast cells which can be recovered from human adenoid tissues varies characteristically in the course of the year. The yield was found to be highest in May and lowest in July. The average histamine content was above average in April, June, July and September. Although the spontaneous histamine release remained relatively constant, the concanavalin A-stimulated histamine release was significantly reduced from June to September.

The human adenoidal mast cell. Susceptibility to different secretagogues and secretion inhibitors.

Mast cells from adenoid tissues of man do not form a homogeneous population but differ in size and ultrastructure. They degranulate on stimulation with specific antigen, ionophore A 23187, Concanavalin A and, under certain conditions, antihuman IgE or acetylcholine. Compound 48/80, dextran, purified C3a or C5a are ineffective. Adenosine exerts either an enhancing or inhibiting effect on the stimulated histamine release, depending on the actual conditions of the mast cells. The study of a range of known mast cell degranulation inhibitors revealed important differences between human adenoidal mast cells and human basophils or animal mast cell systems. The efficacies of the drugs or drug combinations so far tested correspond well with the established therapeutic effects in man.