abstract introduction: resent studies have been shown beneficial effects of hyperoxia pretreatment against ischemia-reperfusion injury in different organs. the aim of the present study was to investigate early and late effects of normobaric hyperoxia (≥95% o2) pretreatment on ischemia-reperfusion injuries in isolated rat hearts. methods: following 60 and 180 minutes of hyperoxia, rat hearts wer...

Human astronauts follow a fixed prebreathing protocol consisting of 100% hyperoxia exposure repeated several times weekly before conducting the extravehicular activities in interplanetary space. However, despite astronaut to both space radiation and hyperoxia, which have different biological effects on cells, combinatorial aging longevity is unknown. Here, we evaluated interactive using Caenorh...

<b><i>Background:</i></b> Preclinical studies have demonstrated that hyperoxia disrupts the intestinal barrier, changes bacterial composition, and injures lungs of newborn animals. <b><i>Objectives:</i></b> The aim study was to investigate effects on lung microbiota communication between develop a predictive model for identification hyperoxia-indu...

Introduction: Ischemic preconditioning (IPC) is an endogenous phenomenon that can induce ischemic tolerance (IT) in variety of organs such as brain. In this study, we examined the intermittent and prolonged dose of normobaric hyperoxia (HO) on neurologic deficit scores, infarct volume, and catalase activity. Material and Method: The rats were divided to four main groups. First two main groups w...

PURPOSE To investigate whether nitric oxide (NO) regulates retinal circulation during and after induction of hyperoxia in cats. METHODS Hyperoxia was induced for 10 minutes with 100% oxygen. The vessel diameter and blood velocity were measured simultaneously in second-order retinal arterioles by laser Doppler velocimetry; the retinal blood flow (RBF) and wall shear rate (WSR) were calculated ...

Exposure of preterm infants to hyperoxia impairs vascular growth, contributing to the development of bronchopulmonary dysplasia and retinopathy of prematurity. Disruption of vascular endothelial growth factor (VEGF)-nitric oxide (NO) signaling impairs vascular growth. Endothelial progenitor cells (EPCs) may play an important role in vascular growth. Endothelial colony-forming cells (ECFCs), a t...

Hyperoxia prolongs the postantibiotic effect (PAE) of the aminoglycoside tobramycin in Pseudomonas aeruginosa. We tested the hypothesis that the PAE is prolonged because hyperoxia increases free radical flux while tobramycin inhibits the induction of antioxidant defenses. Exposure of P. aeruginosa to hyperoxia (100% O2) for 1 h increased superoxide dismutase, catalase, and glutathione levels. I...

Supplemental oxygen is frequently used in the treatment of infants having pulmonary insufficiency, but prolonged hyperoxia may contribute to the development of bronchopulmonary dysplasia in these infants. Cytochrome P4501A enzymes have been implicated in hyperoxic lung injury. Retinoic acid (RA) plays a key role in lung development. Here, we tested the hypotheses that newborn rats exposed to a ...

Premature newborns are frequently exposed to hyperoxic conditions and experimental data indicate modulation of liver metabolism by hyperoxia in the first postnatal period. Conversely, nothing is known about possible modulation of growth factors and signaling molecules involved in other hyperoxic responses and no data are available about the effects of hyperoxia in postnatal liver haematopoiesis...