Javier Cristancho Castañeda

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KEY POINTS Adult animals that have been perinatally exposed to oxygen-rich atmospheres (hyperoxia), recalling those used for oxygen therapy in infants, exhibit a loss of hypoxic pulmonary vasoconstriction, whereas vasoconstriction elicited by depolarizing agents is maintained. Loss of pulmonary hypoxic vasoconstriction is not linked to alterations in(More)
Obstructive sleep apnea is a frequent medical condition consisting in repetitive sleep-related episodes of upper airways obstruction and concurrent events of arterial blood hypoxia. There is a frequent association of cardiovascular diseases and other pathologies to this condition conforming the obstructive sleep apnea syndrome (OSAS). Laboratory models of(More)
AIMS The mechanisms involved in hypoxic pulmonary vasoconstriction (HPV) are not yet fully defined. The aim of the study was to determine the role of protein kinase C zeta (PKCzeta) and neutral sphingomyelinase (nSMase) in HPV. METHODS AND RESULTS Ceramide content was measured by immunocytochemistry and voltage-gated potassium channel (KV) currents were(More)
Superoxide anion is the most important reactive oxygen species (ROS) primarily generated in cells. The main cellular constituents with capabilities to generate superoxide anion are NADPH oxidases and mitochondrial respiratory chain. The emphasis of our article is centered in critically examining hypotheses proposing that ROS generated by NADPH oxidase and(More)
Hypoxia activates erythropoietin-producing cells, chemoreceptor cells of the carotid body and pulmonary artery smooth muscle cells (PSMC) with a comparable arterial PO2 threshold of some 70 mmHg. The inhibition by CO of the hypoxic responses in the two former cell types has led to the proposal that a haemoprotein is involved in the detection of the PO2(More)
Obstructive sleep apnoea syndrome (OSAS) is a disorder characterized by repetitive episodes of complete (apnoea) or partial (hypopnoea) obstruction of airflow during sleep. The severity of OSAS is defined by the apnoea hypopnoea index (AHI) or number of obstructive episodes. An AHI greater than 30 is considered severe, but it can reach values higher than(More)
Hypoxia increases the release of neurotransmitters from chemoreceptor cells of the carotid body (CB) and the activity in the carotid sinus nerve (CSN) sensory fibers, elevating ventilatory drive. According to previous reports, perinatal hyperoxia causes CSN hypotrophy and varied diminishment of CB function and the hypoxic ventilatory response. The present(More)
Revisión de varios métodos para modelar tiempo a múltiples eventos por sujeto: modelamiento de tiempo a hospitalizaciones y muerte Abstract During the disease-recovery process of many diseases, such as in Heart Failure (HF), often more than one type of event plays a role. Some clinical trials use the combined endpoint of death and a secondary event; for(More)
Cigarette smoke (CS) and chronic hypoxia (CH) can produce pulmonary hypertension. Similarities and differences between both exposures and their interaction have not been explored. The aim of the present study was to investigate the effects of CS and CH, as single factors or in combination, on the pulmonary circulation in the guinea pig. 51 guinea pigs were(More)
Oxygen-sensing and transduction in purposeful responses in cells and organisms is of great physiological and medical interest. All animals, including humans, encounter in their lifespan many situations in which oxygen availability might be insufficient, whether acutely or chronically, physiologically or pathologically. Therefore to trace at the molecular(More)