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It has been shown that the formation of calcium phosphate crystals can be detected in patient blood using a polymer microchip manufactured by ultrasonic processing. Ultrasonic processing is recently evolving for the fabrication of low-cost microfluidic devices from thermoplastic polymers. The formation of calcium phosphate crystals can be measured in the blood serum of a patient both optically from a change in turbidity or in electrical resistance.

Liquid phase electron microscopy (LP‐EM) has emerged as a powerful technique for in situ observation of material formation in liquid. Especially the use of graphene as window material provides new opportunities to image biological processes because of graphene's molecular thickness and electron scavenger capabilities. However, in most cases the process of interest is initiated when the graphene liquid cells (GLCs) are sealed, meaning that the process cannot be imaged at early timepoints. Here, a novel cryogenic/liquid phase correlative light/electron microscopy workflow that addresses the delay time between graphene encapsulation and the start of the imaging, while combining the advantages of fluorescence and electron microscopy is reported. This workflow allows imaging to be initiated at a predetermined space and time by vitrifying and thawing at a selected time point. The workflow is demonstrated first by observing multiple day crystallization processes and subsequently highlight its potential by observing a biological process: the complexation of calciprotein particles. The ability to correlate the dynamic complexation observed in a GLC with cryogenic TEM and dynamic light scattering, confirms the validity of observations and underlines the exciting possibilities for LP‐EM in biology. [ABSTRACT FROM AUTHOR]

Alpha2HS-glycoprotein/fetuin-A (Ahsg) is a serum protein preventing soft tissue calcification. In trauma and inflammation, Ahsg is down-regulated and therefore considered a negative acute phase protein. Enhancement of Ahsg expression as a protective serum protein is desirable in several diseases including tissue remodelling after trauma and infection, kidney and heart failure, and cancer. Using reporter gene assays in hepatoma cells combined with electrophoretic mobility shift assays we determined that dexamethasone up-regulates hepatic Ahsg. A steroid response unit at position -146/-119 within the mouse Ahsg promoter mediates the glucocorticoid-induced increase of Ahsg mRNA. It binds the hepatocyte nuclear factor 3beta and CCAAT enhancer binding protein beta (C/EBP-beta). The up-regulation is mediated indirectly via glucocorticoid hormone-induced transcriptional up-regulation in C/EBP-beta protein. A high degree of sequence identity in mouse, rat and human Ahsg promoters suggests that the promoter is similarly up-regulated by dexamethasone in all three species. Therefore, our findings suggest that glucocorticoids may be used to enhance the level of Ahsg protein circulating in serum.