[Carcinomatous meningeosis during cis-platinum treatment of gynaecological cancers (author's transl)]

Two cases of carcinomatous meningeosis are reported. One occurred during cis-platinum combination treatment (PAC-scheme) for advanced ovarian carcinoma and one during the same treatment for a carcinoma of the cervix. Both patients showed no neurological problems prior to chemotherapy. The central nervous symptoms developed rapidly following the administration of small doses of cis-platinum (total dose 160 or 300 mg) and could not be controlled. In one case tumour cells were found in the cerebral spinal fluid. The cause of death could have been an unusually toxic reaction to cis-platinum. A thorough neurological examination prior and during chemotherapy with cis-platinum is necessary in order to recognize toxic side effects of the drug as soon as possible.

[Aminoglutethimide - a new drug for the after care in breast cancer]

Aminoglutethimide is an inhibitor of various steroid hydroxylation reactions in the adrenal gland, the ovary, the testis and the placenta; furthermore, the extraglandular estrogen synthesis is inhibited by blocking the aromatase in the subcutaneous fatty tissue.

New assays for the enzymatic conversion of cholesterol to pregnenolone

Cholesterol side chain cleavage is determined by means of separation of (26-C14)-cholesterol and its radioactively labeled side chain (1-C14)k-isocaproic acid. Alumina minicolumn assay (AMCA): adsorption of cholesterol from an aqueous phase by aluminium oxide, while isocaproic acid can percolate through the column. In modification of a previously described technique (1), cholesterol is quantitatively eluted by ethanol. Filter assay (FA): retention of cholesterol by a membrane filter (pore size less than or equal to 0.1 um) while isocaproic acid can pass the filter. Two-phase scintillation assay (TPSA): pH-dependent partition of isocaproic acid between an organic scintillation mixture and an aqueous phase. The TPSA can be applied for all enzymatic reaction in which the polarity of the radioactive residue which is split off depends on pH values or when the total charge of a polar molecule is changed to an apolar state by cleaving one non-radioactive group (e.g. steroid sulfates) and vice versa. The criteria or reliability of the test systems are described. Bovine adrenal mitochondria were incubated and the side chain cleavage of (26-C14)-cholesterol was studied by the new tests systems and compared to the conversion rates of (4-C14)-cholesterol to its metabolites are determined by thin layer chromatography. A good agreement of all tests was found.

In vitro bioassay for human chorionic gonadotrophin

The adenylate cyclase stimulation (ACS) assay is a new in vitro bioassay for human chorionic gonadotrophin (hCG) which is based on the hCG-induced accumulation of cAMP in the incubation medium of decapsulated rat testes. The detection limit for hCG is 0.7 mIU/ml (P < 0.05). A linear dose-response curve on semilogarithmic plots was obtained using 0.18, 0.45, and 1.125 IU hCG/ml. The precision of the ACS assay was satisfactory (λ-value: 0.20 + 0.02, mean ± sd), n = 14). Intra-assay variation: 15% and inter-assay variation: 20%.

Medium cAMP was determined by means of a bovine adrenal protein binding assay. Sensitivity: 0.2 pmoles cAMP/ml. Range: 2 to 40 pmoles/ml. Intra-assay variations: 5% and inter-assay variation: 8%.

As pre-conditions for the ACS assay, cAMP kinetics and dose-response curves were investigated. In kinetic studies of cAMP production the lag phase between hormone addition and increase of medium cAMP is shortened with higher hCG concentration. The highest concentration of cAMP was measured after an incubation of 3 h. Thereafter the concentration declines exponentially due to a decrease of intracellular cAMP formation and pre-dominating activity of extracellular phosphodiesterase. A prolongation of cAMP half-life from 16.8 min to 218 min was obtained by the addition of theophylline (70 mm).

Pre-treatment of rats with 50 IU sc 48 and 24 h prior to in vitro tests caused a complete inhibition of cAMP response to hCG stimulation. Four weeks after this desensitization, the sensitivity of the testes had recovered to 80%.