SPINA
Structure parameter inference approach for endocrine feedback control
SPINA is software for determining constant structure parameters of endocrine feedback control systems from hormone levels obtained in vivo.
The first version of this cybernetic approach allows for evaluating the functional status of the thyroid gland, i.e. thyroid's secretory capacity (GT or SPINA-GT) and sum activity of peripheral deiodinases (GD or SPINA-GD).
A second version has been developed for insulin-glucose homeostasis. It delivers the secretory capacity of pancreatic beta cells (SPINA-GBeta), an estimate for the insulin receptor gain (SPINA-GR) and a static disposition index as a measure for the loop gain of the feedback loop (SPINA-DI).
Both implementations of SPINA have been validated in clinical studies on the basis of large cohorts.