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It is obvious from these results that CEMOT has been a driving force in the development and application of haemorheology in research and clinical practice. It is my intention that these studies will be developed further. It is also my hope that the various collaborations between the Institutes and the Departments now involved in the CEMOT Research and Clinical Activity can continue and be further developed. The underlying aim is always the resolution of human diseases and the care of patients.

We directly measured pHi using the pH sensitive dye, neutral red. We defined pHi for rectal and gastric tissue in whole tissue and by layer under control and arrest conditions. Fifteen minutes of arrest was not sufficient time to alter the pHi at the rectal or gastric site. On initial inspection, the stomach may be more sensitive to ischemic changes than the rectum. Understanding the mechanism by which PCO_2 generation is used to track clinical changes is vital to the early detection of tissue dysoxia in order to effectively treat and manage critically ill patients.

The rate at which skeletal muscle oxidative phosphorylation adjusts to a new metabolic requirement (“VO_2 kinetics”) is one of the determinants of exercise tolerance. The VO_2 kinetics does not seem to depend, in normal conditions, on O_2 availability, at least for moderate-intensity exercise. A relatively minor limiting factor for the VO_2 kinetics could be the inhibition of mitochondrial respiration by NO. PCr hydrolysis can be considered not only an energy buffer for ATP resynthesis early during the metabolic transition, but also one of the main controllers of oxidative phosphorylation.

The hyperbolic hypoxic ventilatory response vs PaO2, HVRp, is interpreted as relecting a mass hyperbolic relationship of cytochrome PcO2 to cytochrome potential Ec, offset 32 torr by the constant diffusion gradient between arterial blood and cytochrome in CB at its constant metabolic rate $$ \dot VO_2 $$ . Ec is taken to be a linear function of redox reduction and CB ventilatory drive. As Ec rises in hypoxia, the absolute potentials of each step in the citric acid cycle rises equally while the potential drop across each step remains constant because flux rate remains constant. A hypothetic HVRs ( $$ \dot VE $$ vs SaO_2) response curve computed from these assumptions is strikingly non linear. A hypothetic HVRp calculated from an assumed linear HVRs cannot be fit to the observed hyperbolic increase of ventilation in response to isocapnic hypoxia at PO_2 less than 40 torr. The incompatibility of these results suggest that in future studies HVRs will not be found to be linear, especially below 80% SaO_2 and HVRp will fail to be accurately hyperbolic.

Near-infrared tissue spectroscopy is a non invasive, innocuous technique to measure oxygen saturation in tissues. NIR oximetry can be used in almost any area of the body, according to the type of analysis to be done. The development of a laser oximeter, more selective and closer to the requirements of the diffusion theoretical model allows to better evaluate the oxygen saturation from the intensity of the backscattered light at two different wavelengths; the use of a fibre optic probe provides a flexible mechanical connection between the spectroscopic device and the patient, cutting any electrical contact. From the safety point of view, the system has been calibrated following the CEI EN 60825-1 standard and classified as a Class 1 system. Preliminary tests performed on volunteers have shown that CW laser oximeter can easily real time follow variations of the biological tissue oxygenation.