Dorsal and ventral stimuli in cell-material interactions: effect on cell morphology

Cells behave differently between bidimensional (2D) and tridimensional (3D) environments. While most of the in vitro cultures are 2D, most of the in vivo extracellular matrices are 3D, which encourages the development of more relevant culture conditions, seeking to provide more physiological models for biomedicine (e.g., cancer, drug discovery and tissue engineering) and further insights into any dimension-dependent biological mechanism. In this study, cells were cultured between two protein coated surfaces (sandwich-like culture). Cells used both dorsal and ventral receptors to adhere and spread, undergoing morphological changes with respect to the 2D control. Combinations of fibronectin and bovine serum albumin on the dorsal and ventral sides led to different cell morphologies, which were quantified from bright field images by calculating the spreading area and circularity. Although the mechanism underlying these differences remains to be clarified, excitation of dorsal receptors by anchorage to extracellular proteins plays a key role on cell behavior. This approach--sandwich-like culture--becomes therefore a versatile method to study cell adhesion in well-defined conditions in a quasi 3D environment.     

Tissue and blood gamma-glutamyl transferase distribution in the pig.

Gamma-glutamyl transferase distribution was studied in 10 pigs with an average weight of 100 kg. It was shown that kidney had the highest concentration of the enzyme, followed by pancreas, spleen and liver. Blood activities measured in plasma and sera from 54 animals were very similar, ie, 35+/-21 iu/litre for plasma and 36+/-14 iu/litre for serum.     

Gamma Glutamyl Transferase in domestic animals

In domestic animals, Gamma Glutamyl Transferase is mainly in the kidneys, the pancreas and the intestine; its liver activity is relatively high in cows, horses, sheep, and goats and very low in dogs, cats and birds. The use of plasma reference values can help to interpret the variations of serum GGT mainly in hepatobiliary diseases of cattle, sheep, goats and cholestatic disorders of dogs. Urinary GGT is a good test of kidney toxic damage.     

Variations in blood composition in dairy cows during pregnancy and after calving

The effects of pregnancy and of the onset of lactation on blood composition was studied in 21 Friesian cows. Among the 23 components studied only seven showed significant variations. Serum iron decreased at the end of pregnancy while creatinine increased throughout the last six months. There were decreases in blood glucose, cholesterol and alanine aminotransferase at the end of pregnancy. Triglycerides increased rapidly after drying-off and serum urea increased in the first month after calving.