[Effect of mestranol and chlormadinone acetate on TSH, T4, TBC and FT4 index in Turner syndrome]. / Der Einfluss von Mestranol und Chlormadinonazetat auf TSH, T4, TBC und FT4-Index beim Turner-Syndrom.

In 19 patients with Turner's syndrome aged from 12 to 24 years (average age 17.0 years) the influence of mestranol and chlormadinone acetate on both basal and TRH stimulated TSH secretion, total thyroxine (T4), thyroxine binding capacity (TBC) and free thyroxine index (FT4-I) by means of sequential stimulation test (0.5 g arginine hydrochloride/kg body weight, 25 micrograms GnRH and 200 micrograms TRH) was investigated. These investigations were performed before hormonal substitution, during third to 5th cycles of treatment and 4 month after finishing treatment. TSH and T4 serum levels were determined by RIA, TBC by radio reagent assay. The FT4 index was calculated. Mean basal TSH levels both before, during and after hormonal treatment did not differ. Netto TSH level increase were somewhat higher in 8 of the 19 patients during hormonal treatment. TBC and T4 significantly increased under treatment. The rise of FT4 in a few patients under treatment could not be ensured statistically. After finishing treatment the levels of thyroid parameters decreased.

[Tumor marker diagnosis in non-seminomatous testicular tumors using human chorionic gonadotropin (HCG) and alpha fetoprotein (AFP)]. / Tumormarkerdiagnostik bei nicht-seminomatösen Hodentumoren mittels Humanchoriongonadotropin (HCG) und Alpha-Fetoprotein (AFP).

In 28 patients with non-seminomatous testicle tumour the tumour markers human chorionic gonadotropin (HCG) and alpha-fetoprotein (AFP) were determined radioimmunologically and enzymeimmunologically, respectively. While tumours with chorionic carcinoma (n = 8) always were marker-positive, in the embryonic carcinoma in 2 out of 10 cases falsely negative findings appeared. On 5 patients the biochemical monitoring of the course of the testicle tumour disease is demonstrated in detail by means of HCG and AFP and estimated as very helpful method. Advantages and problems of the marker diagnostics are shown and discussed. The positive marker findings were absolutely evident for a metastasation. On the other hand, marker negativation was not always to be equated with absence of a tumour and demanded a further control of the patient by means of all other available methods of diagnostics up to the second-look-operation.

Characterization by Scatchard plots of monoclonal antibody enzyme conjugates directed against alpha-1-foetoprotein.

A radioimmunoassay was used to investigate the affinity of 2 monoclonal antibodies against human alpha-1-foetoprotein before and after conjugation with horseradish peroxidase. The equilibrium constant of the high-affinity antibody was reduced 10-fold whereas it remained unaffected in the low-affinity antibody. With the Scatchard diagram, quantification of unlabelled antibodies in the unpurified conjugate mixture is also possible if antibody affinity is changed by the coupling procedure.

[Coagulation of 125I bovine fibrinogen]. / Untersuchungen zur Gerinnbarkeit von 125I-Rinderfibrinogen.

Bovine fibrinogen was labelled with 125I using the chloramine T method or the iodogen method and the clottability of the preparations was studied in vitro and in vivo. Three days after radioiodination the in vitro clottability was 82.3% (chloramine T) and 80.4% (iodogen), respectively. When the solutions were allowed to stand at 4 degrees C for 13 days, the in vitro clottability decreased to 70% or 60%, respectively; either preparation was practically unclottable after 25 days. The preparations were administered to rats three days following radioiodination. They showed the same elimination rate and, on thrombin infusion, the same clottability. 125I-labelled (chloramine T) bovine fibrinogen stored in solution at -20 degrees C for 38 days showed a clottability of 76%, the in vivo clottability was unchanged.

[A 125I-thyronine derivative of high specific activity and radiochemical stability (pseudo-T4) (author's transl)]. / Uber ein 125I-Thyroninderivat hoher spezifischer Aktivität und radiochemischer Stabilität (Pseudo-T4).

Under the described reaction conditions for the synthesis of 125I-labelled thyroid hormones by the chloramine-T method, electrophilic substitution of the phenolic ring at positions 3' and 5' is accompanied by an exchange reaction. The proportions of mono- and diiodo-thyronine derivatives formed in this reaction depend on the specific activity of the 125I starting material. Doubly labelled molecules are far less stable than mono products, because the radioactive decay of one iodine atom is followed by destruction of the molecule itself, and the remaining iodine atom is released as I-. In the case of thyroxine with two equivalent substitution positions, there is always a high yield of doubly labelled molecules. By using a thyronine derivative containing a non-radioactive bromine atom in one of the two ortho positions of the 3,5-diiodothyronine molecule, it was possible to produce a "pseudo-T4" of high specific activity and excellent radiochemical stability by radioiodination of the second position. The immunological properties resemble those of T4. This compound may be useful as a tracer for the determination of free T4.

[Radioimmunologic technics for luteinizing hormone determination in cattle and sheep]. / Radioimmunologische Testmethoden zur Luteinisierungshormonbestimmung bei Rind und Schaf.

The antigen relationship which exists between luteinising hormone of various animal species, on the one hand, and human luteinising hormone as well as human chorionic gonadotrophin, on the other, was the background against which possible approaches were tested to the preparation of a heterologous in-vitro test for serum LH determination in cattle and sheep. The following conclusions may be drawn from the results so far obtained: --A homologous or heterologous test with specific relevance to the determination of human LH, on the basis of hLH-anti-hLH or hLH-anti-hCG is not suitable for the determination of LH in animal serum (cattle, sheep). --Quantitative and specific measurement of LH concentrations in the blood of cattle (sheep) is possible by means of an ovine-LH-anti-ovine/bovine-LH (or anti-bovine-LH) test system which is based on cross-reactivity between luteinising hormones of cattle and sheep. --Differentiated measurement of various LH concentrations in animal serum will be possible under certain specific assay conditions, with ovine LH as tracer, ovine or bovine LH as standard, and hCG antiserum. Yet, the clinical value of that heterologous radio-immuno-assay method is attributable primarily to its potential to measure peak values within the cycle to determine the time of ovulation rather than to the built-in possibility to determine base values of the cycle.

[Animal experiments on the pharmacokinetics of ocrase (author's transl)]. / Tierexperimentelle Untersuchungen zur Pharmakokinetik von Ocrase.

The blood level, distribution and elimination of ocrase, a protease from Aspergillus ochraceus, were determined in rabbits after application of the 131I labelled enzyme in therapeutic doses.