Neurofilament Light Chain Is Associated With Acute Mountain Sickness.

Background: Neurological symptoms are common in acute mountain sickness (AMS); however, the extent of neuroaxonal damage remains unclear. Neurofilament light chain (NfL) is an established blood biomarker for neuroaxonal damage.

Objective: To investigate whether plasma (p) NfL levels increase after simulated altitude exposure, correlate with the occurrence of AMS, and might be mitigated by preacclimatization.

A Single Residue within the MCR-1 Protein Confers Anticipatory Resilience.

The envelope stress response (ESR) of Gram-negative enteric bacteria senses fluctuations in nutrient availability and environmental changes to avert damage and promote survival. It has a protective role toward antimicrobials, but direct interactions between ESR components and antibiotic resistance genes have not been demonstrated. Here, we report interactions between a central regulator of ESR , the two-component signal transduction system CpxRA (onjugative ilus epression), and the recently described mobile colistin resistance protein (MCR-1).

Carry-Over Quality of Pre-acclimatization to Altitude Elicited by Intermittent Hypoxia: A Participant-Blinded, Randomized Controlled Trial on Antedated Acclimatization to Altitude.

Intermittent normobaric hypoxia (IH) is increasingly used to pre-acclimatize for a sojourn to high altitude. There is a number of hypoxia - protocols observing the hypoxic ventilatory response (HVR), but little is known about the carry - over quality of the Lake Louise Score (LLS). We thus studied a week - long, 1 h per day poikilocapnic hypoxia protocol on whether acclimatization could be carried over for one week.

Systemic Blood Pressure Variation During a 12-Hour Exposure to Normobaric Hypoxia (4500 m).

This study was aimed at evaluating a potential association between blood pressure variation and acute mountain sickness (AMS) during acute exposure to normobaric hypoxia. A total of 77 healthy subjects (43 males, 34 females) were exposed to a simulated altitude of 4500 m for 12 hours. Peripheral oxygen saturation, heart rate, systemic blood pressure, and Lake Louise AMS scores were recorded before and during (30 minutes, 3, 6, 9, and 12 hours) hypoxic exposure.

Is decision making in hypoxia affected by pre-acclimatisation? A randomized controlled trial.

Introduction: Decision making is impaired in hypoxic environments, which may have serious or even lethal consequences for mountaineers. An acclimatisation period prior to high altitude exposures may help to overcome adverse effects of hypoxia. Thus, we investigated possible effects of short-term pre-acclimatisation on decision making in hypoxia.

Is acute mountain sickness related to trait anxiety? A normobaric chamber study.

Introduction: Some mountaineers are more prone to the occurrence of acute mountain sickness (AMS) than others. State anxiety during altitude exposure might be associated with AMS development. We hypothesized that trait anxiety might be higher in AMS cases compared to non-AMS cases.

Hypoxia triggers high-altitude headache with migraine features: A prospective trial.

Background: Given the high prevalence and clinical impact of high-altitude headache (HAH), a better understanding of risk factors and headache characteristics may give new insights into the understanding of hypoxia being a trigger for HAH or even migraine attacks.

Methods: In this prospective trial, we simulated high altitude (4500 m) by controlled normobaric hypoxia (FiO2 = 12.6%) to investigate acute mountain sickness (AMS) and headache characteristics.

Influence of Acute Normobaric Hypoxia on Hemostasis in Volunteers with and without Acute Mountain Sickness.

Introduction: The aim of the present study was to investigate whether a 12-hour exposure in a normobaric hypoxic chamber would induce changes in the hemostatic system and a procoagulant state in volunteers suffering from acute mountain sickness (AMS) and healthy controls.

Materials And Methods: 37 healthy participants were passively exposed to 12.6% FiO2 (simulated altitude hypoxia of 4,500 m).

Symptom progression in acute mountain sickness during a 12-hour exposure to normobaric hypoxia equivalent to 4500 m.

The diagnosis and quantification of severity of acute mountain sickness (AMS) continue to be problematic. What symptoms should be included in a score and how to weigh any given symptom in the total score remain matter of debate. Seventy seven healthy male (n=43) and female (n=34) volunteers, aged between 18 and 42 years, were exposed to normobaric hypoxia (Fio2=12.

Resting arterial oxygen saturation and breathing frequency as predictors for acute mountain sickness development: a prospective cohort study.

Introduction: The study evaluated the predictive value of arterial oxygen saturation (SaO2) after 30-min hypoxic exposure on subsequent development of acute mountain sickness (AMS) and tested if additional resting cardio-respiratory measurements improve AMS prognosis.

Methods: Fifty-five persons were exposed to a simulated altitude of 4,500 m (normobaric hypoxia, FiO2 = 12.5%).

Association between body water status and acute mountain sickness.

Purpose: The present study determined the association between body fluid variation and the development of acute mountain sickness (AMS) in adults.

Methods: Forty-three healthy participants (26 males and 17 females, age: 26 ± 6 yr, height: 174 ± 9 cm, weight: 68 ± 12 kg) were passively exposed at a FiO2 of 12.6% (simulated altitude hypoxia of 4500 m, PiO2 = 83.

MRI evidence: acute mountain sickness is not associated with cerebral edema formation during simulated high altitude.

Acute mountain sickness (AMS) is a common condition among non-acclimatized individuals ascending to high altitude. However, the underlying mechanisms causing the symptoms of AMS are still unknown. It has been suggested that AMS is a mild form of high-altitude cerebral edema both sharing a common pathophysiological mechanism.

Race performance and exercise intensity of male amateur mountain runners during a multistage mountain marathon competition are not dependent on muscle strength loss or cardiorespiratory fitness.

The aims of this study were to quantify the cardiorespiratory fitness level of amateur mountain runners and to characterize the related cardiorespiratory and muscular strain during a multistage competition. Therefore, 16 male amateur participants performed an incremental treadmill test before the Transalpine-Run 2010. Besides race time, heart rate (HR) was monitored using portable HR monitors during all stages, and countermovement jump ability was assessed after each stage.

Cardiac troponins in young marathon runners.

Cardiac troponin increases are common in adult marathon finishers. However, data on troponin values for young marathon runners are scarce. Forty young runners (20 healthy male and 20 female) 13 to 17 years old participated in this study.

Short-term exposure to hypoxia for work and leisure activities in health and disease: which level of hypoxia is safe?

Introduction: Exposures to natural and simulated altitudes entail reduced oxygen availability and thus hypoxia. Depending on the level of hypoxia, the duration of exposure, the individual susceptibility, and preexisting diseases, health problems of variable severity may arise. Although millions of people are regularly or occasionally performing mountain sport activities, are transported by airplanes, and are more and more frequently exposed to short-term hypoxia in athletic training facilities or at their workplace, e.

Risk factors for high-altitude headache in mountaineers.

Aim: The aim was to identify most relevant risk factors of high-altitude headache within a broad mountaineering population through a prospective, observational, rater-blinded study.

Methods: A total of 506 mountaineers were enrolled after their first overnight stay in one of seven alpine huts between 2200-3817 m. Structured interview including information on mountaineering histories, caffeine intake, smoking habits, alcohol consumption, intake of medication, rate of ascent, physical fitness, the level of exertion and the amount of fluids intake at the day of ascent were recorded along with a standardized medical examination.

The prevalence of and risk factors for acute mountain sickness in the Eastern and Western Alps.

Acute mountain sickness (AMS) is the most common condition of high altitude illnesses. Its prevalence varies between 15% and 80% depending on the speed of ascent, absolute altitude reached, and individual susceptibility. Additionally, we assumed that the more experienced mountaineers of the Western Alps are less susceptible to developing AMS than recreational mountaineers of the Eastern Alps or tourist populations.

Prevalence of acute mountain sickness in the Eastern Alps.

Little information is available on the prevalence of acute mountain sickness (AMS) in the Eastern Alps compared with the Western Alps. Because of differences regarding the populations of mountaineers, we hypothesized that the prevalence differs between the Eastern and Western Alps. Thus, we determined the prevalence and risk factors of AMS at four different altitudes in the Eastern Alps of Austria.