An imaging method for oxygen distribution, respiration and photosynthesis at a microscopic level of resolution.

Biological samples are far from homogeneous, with complex compartmentation being the norm. Major physiological processes such as respiration do not therefore occur in a uniform manner within most tissues, and it is currently not possible to image its gradients in living plant tissues. A compact fluorescence ratiometric-based device is presented here, consisting of an oxygen-sensitive foil and a USB (universal serial bus) microscope.

Methodology and Significance of Microsensor-based Oxygen Mapping in Plant Seeds - an Overview.

Oxygen deficiency is commonplace in seeds, and limits both their development and their germination. It is, therefore, of considerable relevance to crop production. While the underlying physiological basis of seed hypoxia has been known for some time, the lack of any experimental means of measuring the global or localized oxygen concentration within the seed has hampered further progress in this research area.

Hypoxia in static and dynamic 3D culture systems for tissue engineering of bone.

Tissue engineering of sizeable cell-scaffold constructs is limited by gradients in tissue quality from the periphery toward the center. Because homogenous delivery of oxygen to three-dimensional (3D) cell cultures remains an unsolved challenge, we hypothesized that uneven oxygen supply may impede uniform cellular growth on scaffolds. In this study we challenged static and dynamic 3D culture systems designed for bone tissue engineering applications with a well-growing subclone of MC3T3-E1 preosteoblasts and continuously measured the oxygen concentrations in the center of cell-seeded scaffolds and in the surrounding medium.

Construction and validation of a microprocessor controlled extracorporal circuit in rats for the optimization of isolated limb perfusion.

Although a few experimental approaches to isolated limb perfusion (ILP) are described in the literature, none of these animal models mimics the clinical perfusion techniques adequately to improve the technique of ILP on the basis of valid preclinical data. Therefore, we developed an ILP setup in rats allowing online monitoring of essential perfusion parameters such as temperature (in perfusate, various tissues, and rectum), pH (perfusate), perfusion pressure, and O(2) concentration (in perfusate, tissue), by a tailor-made data acquisition system. This setup permits close supervision of vital parameters during ILP.