Adv Exp Med Biol
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Sensory information in the lung is generated by airway receptors located throughout the respiratory tract. This information is mainly carried by the vagus nerves and yields multiple reflex responses in disease states (cough, bronchoconstriction and mucus secretion). ⋯ A single sensory unit contains homogeneous or heterogeneous types of receptors, providing varied and mixed behavior. Thus, the sensory units are not only transducers, but also processors that integrate information in different modes.
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Forkhead Transcription Factors: Vital Elements in Biology and Medicine provides a unique platform for the presentation of novel work and new insights into the vital role that forkhead transcription factors play in both cellular physiology as well as clinical medicine. Internationally recognized investigators provide their insights and perspectives for a number of forkhead genes and proteins that may have the greatest impact for the development of new strategies for a broad array of disorders that can involve aging, cancer, cardiac function, neurovascular integrity, fertility, stem cell differentiation, cellular metabolism, and immune system regulation. Yet, the work clearly sets a precedent for the necessity to understand the cellular and molecular function of forkhead proteins since this family of transcription factors can limit as well as foster disease progression depending upon the cellular environment. ⋯ Furthermore, FoxO transcription factors are exciting considerations for disorders such as cancer in light of their pro-apoptotic and inhibitory cell cycle effects as well as diabetes mellitus given the close association FoxOs hold with cellular metabolism. In addition, these transcription factors are closely integrated with several novel signal transduction pathways, such as erythropoietin and Wnt proteins, that may influence the ability of FoxOs to lead to cell survival or cell injury. Further understanding of both the function and intricate nature of the forkhead transcription factor family, and in particular the FoxO proteins, should allow selective regulation of cellular development or cellular demise for the generation of successful future clinical strategies and patient well-being.
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Some preterm infants have poor cerebral autoregulation. The concordance between cerebral intravascular oxygenation (HbD), computed as the difference between oxygenated (HbO2) and deoxygenated (Hb) haemoglobin, and mean arterial blood pressure (MABP) reflects impaired autoregulation. As HbD is not an absolute value, we developed mathematics to prove that the cerebral tissue oxygenation (TOI), an absolute signal computed as the ratio of HbO2 to total haemoglobin (Hb+HbO2), may replace HbD. ⋯ HbD and TOI were obtained with the NIRO-300 (Hamamatsu, Japan). Invasive MABP was measured continuously. All mathematics showed a strong similarity between HbD and TOI.
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The objective was to assess the ability of near infrared spectrophotometry (NIRS) to detect changes in tissue oxygenation due to alterations in oxygen delivery. Ten hemodynamically stable preterm neonates with a median gestational age of 27.9 weeks (range 25.1-31.2), a median birth weight of 840g (range 690-1310), and a postnatal age of 29 days (range 2-45) were included in this prospective trial. ⋯ This decrease correlated positively with the weight matched amount of packed red cell transfusion (r2=0.40, p<0.05) and with the increase in hematocrit (r2=0.58, p<0.005). The OEI obtained by a NIRS may allow to monitor changes in tissue oxygenation.
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Intracranial pressure (ICP) monitoring is indispensable in the assessment of neurotrauma in humans and animal models. It was shown that cerebellar ICP, leaving the cortical area intact, can replace cerebral ICP in rats. While cerebral probes may induce spreading depression, the effects of a miniature cerebellar probe on near infrared spectroscopy (NIRS) measurements and cerebral hemodynamics are not known. ⋯ Because the decreased CBF was accompanied by an increased arterio-venous oxygen difference (p=0.026) and unaltered cerebral metabolic rate of oxygen (p=0.485), this suggests an uncoupling. These data suggest that a cerebellar miniature Codman ICP probe induces an uncoupling of cerebral metabolism and CBF. In addition, NIRS is found to be a robust technique: even when path lengths are altered after probe insertion, physiological alterations can still be examined.