Oxidative Stress Reaction to Hypobaric-Hyperoxic Civilian Flight Conditions.

Background: In military flight operations, during flights, fighter pilots constantly work under hyperoxic breathing conditions with supplemental oxygen in varying hypobaric environments. These conditions are suspected to cause oxidative stress to neuronal organ tissues. For civilian flight operations, the Federal Aviation Administration (FAA) also recommends supplemental oxygen for flying under hypobaric conditions equivalent to higher than 3048 m altitude, and has made it mandatory for conditions equivalent to more than 3657 m altitude.

Influence of nutrition and food on sleep-is there evidence?

Background: The influence of sleep disorders on metabolism, especially concerning obesity and diabetes, as well as obesity and obstructive sleep apnea, has been widely investigated. However, the effect of nutrition and the intake of certain foods on sleep has only recently gained attention. In recent years, there have been publications on intake of certain foods and certain diets regarding their influence on sleep, as well as activity of adipocytes and their effect on production of sleep hormones.

Weight Loss and Fat Metabolism during Multi-Day High-Altitude Sojourns: A Hypothesis Based on Adipocyte Signaling.

Several publications and random observations have reported weight loss in high-altitude sojourners of both sexes. This could be a result of multiple adaptations, which hypoxia and mountaineering provoke on a cellular and organic level. Several publications have discussed the effect on appetite-regulating hormones to be one of the main contributing factors.

Expiratory Peak Flow and Minute Ventilation Are Significantly Increased at High Altitude versus Simulated Altitude in Normobaria.

Simulated altitude (normobaric hypoxia, NH) is used to study physiologic hypoxia responses of altitude. However, several publications show differences in physiological responses between NH and hypobaric conditions at altitude (hypobaric hypoxia, HH). The causality for these differences is controversially discussed.

Extreme sports performance for more than a week with severely fractured sleep.

Purpose: Severely fractured sleep is mostly portrayed negatively, but investigations in extreme sports show that humans can maintain performance with a minimum of sleep. With two cases of long-lasting extreme sports performances, we demonstrate that severely fragmented sleep does not necessarily lead to a deterioration of physical and cognitive performance.

Methods: We performed continuous polysomnography on a 34 year-old skier for 11 days and nights during a world record attempt in long-term downhill skiing and monitored a 32 year-old cyclist during the Race Across America for 8.

Periodic breathing in healthy young adults in normobaric hypoxia equivalent to 3500 m, 4500 m, and 5500 m altitude.

Purpose: The occurrence of periodic breathing (PB) at high altitude during sleep and the quality of sleep are individually different and influenced by multiple factors including sex. Although poor sleep quality at high altitude might not be directly linked to oxygen desaturations, the PB upsurge at high altitude leads to significant oscillations in oxygen saturation.

Methods: Thirty-three students were recruited.

Adiponectin, Leptin and Visfatin in Hypoxia and its Effect for Weight Loss in Obesity.

Hypoxia induces leptin gene expression in human adipocytes via hypoxia-inducible factors (HIF-α/β). Under ambient moderate hypoxia, leptin in adipocytes is elevated for at least 14 days. Leptin is supposedly involved in the reduced food intake, increased utilization of fatty acids for energy production and possible weight loss observed at high altitudes.

The Linkage between Breast Cancer, Hypoxia, and Adipose Tissue.

Objective: The development of breast cancer cells is linked to hypoxia. The hypoxia-induced factor HIF-1α influences metastasis through neovascularization. Hypoxia seems to decrease the responsiveness to hormonal treatment due to loss of estrogen receptors (ERs).

Endurance Training in Normobaric Hypoxia Imposes Less Physical Stress for Geriatric Rehabilitation.

Evidence suggests that training in hypoxia can be very effective even while requiring less physical effort. We therefore aimed to measure the effect of endurance training under hypoxic conditions on pulmonary and cardiovascular parameters in an elderly population undergoing inpatient rehabilitation. Forty patients over age 65 years with multiple co-morbid conditions were recruited during a 3-week stay in a geriatric rehabilitation center.

Normobaric hypoxia overnight impairs cognitive reaction time.

Background: Impaired reaction time in patients suffering from hypoxia during sleep, caused by sleep breathing disorders, is a well-described phenomenon. High altitude sleep is known to induce periodic breathing with central apneas and oxygen desaturations, even in perfectly healthy subjects. However, deficits in reaction time in mountaineers or workers after just some nights of hypoxia exposure are not sufficiently explored.

SpO and Heart Rate During a Real Hike at Altitude Are Significantly Different than at Its Simulation in Normobaric Hypoxia.

Exposures to simulated altitude (normobaric hypoxia, NH) are frequently used in preparation for mountaineering activities at real altitude (hypobaric hypoxia, HH). However, physiological responses to exercise in NH and HH may differ. Unfortunately clinically useful information on such differences is largely lacking.

Principles of practice parameters for the treatment of sleep disordered breathing in the elderly and frail elderly: the consensus of the International Geriatric Sleep Medicine Task Force.

Sleep disordered breathing (SDB) is a leading cause of morbidity worldwide. Its prevalence increases with age. Due to the demographic changes in industrial societies, pulmonologists and sleep physicians are confronted with a rapidly growing number of elderly SDB patients.

Normobaric Intermittent Hypoxia over 8 Months Does Not Reduce Body Weight and Metabolic Risk Factors--a Randomized, Single Blind, Placebo-Controlled Study in Normobaric Hypoxia and Normobaric Sham Hypoxia.

Objective: Both a 1- to 4-week continuous or intermittent stay and moderate exercise in hypoxia versus normoxia can lead to weight loss. We examined the reproducibility and durability of added hypoxic exposure in a feasible health program of several months.

Methods: 32 obese persons, randomly assigned to either a hypoxia (age 50.

The actual role of sodium cromoglycate in the treatment of asthma--a critical review.

Introduction: Despite international consensus and clearly written guidelines urging wider use of corticosteroids or combinations of inhaled short- and long-acting β-agonists (SABA and LABA) and corticosteroids in persistent asthma, prescribing patterns and compliance rates fall far short of recommendations.

Objectives: The failure to use steroids more aggressively is due, in part, to their side effects, even with inhaled forms of the drug. There is a role for expanded use of sodium cromolyn in asthma.

Metabolic changes through hypoxia in humans and in yeast as a comparable cell model.

Background: In several investigations on mountaineers under moderate hypoxia, at altitudes between 2,500 m and 4,500 m, weight loss occurs, fat levels in the serum and insulin resistance (in diabetic mountaineers) are reduced. Animal studies with different time dosage regimens of hypoxia in animal cages revealed different and partly confusing results regarding fat metabolism under hypoxia.

Hypotheses: Hypothesis for the change in glucose and fat metabolism include a HIF promoted higher leptin rate under hypoxia and an increased glucose transport in peripheral organs.

The need for pressure changes in CPAP therapy 2-3 months after initial treatment: a prospective trial in 905 patients with sleep-disordered breathing.

Objective: The aim of the study was to investigate the need for pressure change in patients with sleep-disordered breathing (SDB) several weeks after therapy initiation. We prospectively studied 905 consecutive patients (740 men and 165 women) with SDB and therapeutic intervention with continuous positive airway pressure (CPAP)/bilevel PAP.

Methods: Several weeks after therapy initiation, patients were restudied for control, and pressure was optimized if it was necessary.