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M Hellwich

Publications and source records attributed to M Hellwich.

6 recordsLinked to original sources
PubMed1987

[Value of the intracutaneous skin test in analgesic intolerance in comparison with oral provocation].

A total of 24 patients showing predominantly urticarial and/or anaphylactic reactions to analgesics were exposed to the suspicious agents by means of skin testing and oral provocation. Only two patients, who had already shown mild anaphylactic symptoms during the skin test, were excluded from the oral provocation test. In 19 out of 24 cases, the presumed intolerance of analgesics could be confirmed by oral provocations, i.e., the rate of accuracy was 79%. Five patients tolerated the usual therapeutic single doses of previously suspicious agents, although 3 of them had shown positive skin tests. Two patients failed to show suspicious symptoms in both skin and oral provocation test. 14 patients reacted to propyphenazone, 6 patients to metamizole, and one patient each additionally to salicylamide or phenylbutazone. In the majority of the cases, parallel skin tests with all test agents were performed, using both aqueous suspension and the so-called serum linkage. Principally, both procedures proved equally good. In our patients, the skin tests (prick and intracutaneous test) were only reliable regarding the demonstration of propyphenazone allergy. 16 out of 19 patients showed the same reactions to both skin test and oral provocation (84%); in 3 cases, however, the skin tests to propyphenazone were false positive. The rate of accuracy in the metamizole skin test was 45%. With regard to the remaining suspicious agents, only 2 out of 6 positive skin tests were confirmed by oral provocation. In total, the numbers of true positive and false positive skin tests were almost equal. Thus, the demonstration of analgesic intolerance by history and skin test was only possible with a probability rate of 50%. By oral provocation, however, analgesic intolerance could be proved in almost 80% of the cases. Regarding the remaining 5 patients, we must assume that they were devoid of true analgesic allergy in spite of partly positive skin tests and apparently confirmative history.

Administration, Oral↗
PubMed1986

[A case report of Jadassohn anetoderma].

Itchy pink plaques have been developing on the trunk of a 29-year-old patient for two years. After a few weeks, these plaques usually change into atropic scars. Both types of efflorescence occur simultaneously. Histological examination of a fresh lesion showed leucocytoclastic vasculitis. These micromorphological changes are no longer visible in the atrophic scars. The clinical picture and histological findings are identical with those seen in Jadassohn's anetoderma. The histological changes correspond with the degenerative-inflammatory process first described by Cramer in 1963.

Adult↗
PubMed1983

[5-S-cysteinyldopa determination in the urine. Its value for monitoring in melanoma patients].

In case of uncharacteristic patient complaints or slightly pathologic BSR or liver enzyme levels in patients, suffering from melanoma, the determination of 5-S-cysteinyldopa in the 24-h-urine may be of great diagnostic value. If the complaints and the pathologic values are early symptoms and signs of generalized metastases being clinically not yet manifest, the excretion of 5-S-cysteinyldopa in the urine is often increased. In such cases, a thorough and possibly invasive search for metastases is indicated.

Cysteinyldopa↗
PubMed1982

Energy-dependent extrusion of cyclic 3',5'-adenosine-monophosphate. A drug-sensitive regulatory mechanism for the intracellular nucleotide concentration in rat erythrocytes.

In reticulocyte-rich suspensions of red blood cells from rats extrusion of cAMP as a regulatory mechanism of intracellular cAMP was investigated. In response to isoprenaline and/or the phosphodiesterase inhibitors Ro 20-1724 and rolipram extrusion of cAMP increases dependent on the concentration of the drugs and time of exposure. However, these drugs exert their effects on the extrusion of cAMP only indirectly, i.e. via increased intracellular levels of cAMP, since the respective EC50-values of the drugs for intracellular accumulation and extrusion of cAMP are identical (isoprenaline: approximately 50 nM; rolipram: approximately 1 microM; Ro 20-1724: 15 microM). The dependence of the rate of extrusion on intracellular levels of cAMP is characterized by a typical concentration-effect relationship from which a maximal capacity of cAMP extrusion of 3-6 nmol/10 min/10(9) cells and a half maximal effective intracellular cAMP concentration of 40-50 nmol/10(9) cells can be derived. This relationship has been inferred from either kinetic or steady-state approaches. At rapidly changing intracellular levels of cAMP an apparent time lag of extracellular cAMP accumulation is obligatorily conditioned by this relationship. Vasodilating drugs which lower the ATP content of the cells as well as the uncoupler of oxidative phosphorylation, FCCP, inhibit the extrusive process (papaverine greater than FCCP greater than dipyridamole greater than dilazep much greater than hexobendine greater than or equal to carbocromene) leading to a 3-5-fold increase of the intrato extracellular concentration gradient of cAMP. It is concluded that extrusion of cAMP is a saturable and energy-dependent process which regulates the intracellular cAMP concentration independent of the activities of adenylate cyclase and phosphodiesterase.

Adenosine Triphosphate↗
PubMed1978

Correlation between isoprenaline-stimulated synthesis of cyclic AMP and occurrence of beta-adrenoreceptors in immature erythrocytes from rats.

When increasing reticulocytosis (up to 80%) was induced in rats by treatment with acetyl-phenylhydrazine (up to 70 mg/kg on 3 consecutive days) synthesis of cAMP stimulated by isoprenaline in intact red blood cells and in the related membrane preparations increased up to 100-fold. At the same time the density of beta-adrenoreceptor sites (measured by ligand binding with (3H)(-)-dihydroalprenolol) in the related membrane preparations was only increased about 5-fold. There was however a linear correlation between the increase of isoprenaline-stimulated enzyme activity and the receptor density in membrane preparations. The results indicate that mature red cells contain beta-adrenoreceptor sites but little or not adenyl cyclase activity. Thus, during the maturation process of these cells, enzyme activity and receptor densities decrease at different speeds indicating a different turnover of these two entities of the cytoplasmic membrane.

Adenylyl Cyclases↗