Zugl.: Giessen, Univ., Diss., 2005

Thesis (doctoral)--Rheinisch-Westfälische Technische Hochschule Aachen, 1994.

Universiẗat, Diss., 2005--Giessen.

Universiẗat, Diss., 2005--Giessen.

Universiẗat, Diss., 2007--Giessen.

Ulm, Univ., Diss., 2008.

Ulm, Univ., Diss., 2008.

Neubestimmung der Referenzbereiche für die Schilddrüsenhormonparameter TSH, fT3 und fT4 für Kinder von der Geburt bis zum 18. Lebensjahr mittels Immulite Immunoassay. / Creation of new reference values for thyroid hormones TSH, fT3 and fT4 for children using the Immulite immunoassay

The thesis deals with the evaluation of the impact of different quantities and forms of iodine in ration dairy cows on the concentration of hormones of the thyroid in the blood plasma. The experiment was done with a herd of Red cows breeding in the conversion to breed in the breeding of Holstein dairy cows in Klatovy. Iodine was given in both inorganic and organic form. Before experimenting, the value of total and free forms of hormones was very low. During the experiment, increased concentrations of hormones in connection with the intake of inorganic iodine, the significant deviations showed free forms of thyroid hoemones. Nevertheless, the addition of organic iodine was not fully substituted for the reduction of inorganic iodine content. The thesis also discusses the assessment of the thyroid status by Czech red cattlebreeding on the school farm. The aim was to compare the activity of the thyroid gland in high-yield dairy cows breeding in a barn environment and cattle on pasture reared cattle. For red cattle reared on pasture, there were characteristically higher concentration levels of total and free hormones compared with high yield dairy cows. Nevertheless, in comparison with the reference value,there was a concentration of TT4 for Czech red cattlelower, it coresponded well as dairy cows, rather lower iodine supply. In connection with the rise (higher content) TT4, possibly fT4, there was a similar tendency for the TT3 and fT3, so we can´t assume a deeper state of iodine deficiencies and its associationwith an underactive thyroid gland.

Objectives: We systematically investigated normally or subclinically increased thyroid stimulating hormone (TSH) values associated with unexpectedly increased thyroxine (FT4) and free triiodothyronine (FT3) in findings of patients without any thyroid disease. Moreover, we looked for alternatives to overcome such states with an improved diagnostic procedure and to investigate the pathogenetic background of the respective patients. Methods: Samples with TSH concentrations within the range of 0.4–10 mU/L combined with increased concentrations of FT4 (n=120; Cobas, Roche) were collected over a period of around six years. Cobas FT4 results were compared with measurements from Liaison (DiaSorin) and Architect (Abbott) FT4 assays. For further validation all samples were measured for total thyroxine (TT4) (Cobas, Roche). Finally, FT3 and TT3 as complementary parameters were measured in samples with leftover material. To overcome potential analytical disturbances from stimulating heterophilic antibodies, we used heterophilic blocking tubes (HBTs). Results: From the 120 samples with increased FT4 concentrations by Cobas, 51/120 were also increased by Liaison, and 26/120 by Architect. However, the measurement of TT4 indicated only n=10/120 increased values. The number of increased FT3 (n=71) measurements was higher in Architect>Cobas>Liaison (28>27>9). TT3 levels of 70/71 samples were within the reference interval. HBTs were inappropriate to reduce unspecific immunoreactivity in our samples. No clear pathogenetic background could be elucidated in the anamnesis of individual patients. Conclusions: To overcome dubious constellations of TSH, FT4, and FT3, it is helpful to measure TT4 and TT3 for control or to use an immunoassay with an alternative assay design for the respective parameters.:I. Abkürzungsverzeichnis 4 I. Einleitung 5 1.1 Hintergrund 5 1.2 Regelkreis 7 1.3. Methodik zur Diagnostik von Schilddrüsenhormonen 8 1.5. Störfaktoren 9 1.6 Fragestellungen/Ziele 11 2 Publikationsmanuskript 13 3 Zusammenfassung der Arbeit 23 4 Literaturverzeichnis 27 II Anhang 37 III Darstellung des eigenen Beitrags 40 IV Erklärung über die eigenständige Abfassung der Arbeit 41 V Curriculum vitae 42 VI Publikationen 44 VII Danksagung 45