View clinical trials related to Weightlessness.
Filter by:Anemia is a lack of red blood cells (RBCs) in the circulation. Because RBCs carry the oxygen your body needs to function, anemia can affect one's ability to stay awake, alert, and perform physical activities. Anemia may happen for several reasons, including increased RBC destruction. Anemia often occurs in people who have been in bed for long periods (e.g., if they are very sick) or have decreased mobility (anemia of immobility). Interestingly, astronauts who have left Earth and traveled in space also return anemic. In fact, 5 decades of NASA data showed that astronauts' anemia was more severe the longer they were in space. In another study, astronauts aboard the International Space Station were shown to destroy 54% more of their RBCs in space. RBC destruction may be the culprit of space anemia as well as anemia of immobility on Earth. The ANEMIA Study proposes to measure key aspects of RBC destruction in astronauts in space. These measures will test critical hypotheses on the effects of spaceflight on red blood cells.
Dry immersion (DI) is a ground-based model of prolonged conditions of simulated microgravity. Dry immersion involves immersing the subject in water covered with an elastic waterproof fabric. As a result, the immersed subject, who is freely suspended in the water mass, remains dry. Within a relatively short duration, the model can faithfully reproduce most physiological effects of actual microgravity, including centralization of body fluids, support unloading, and hypokinesia. The main objective of the present study is to investigate the physiological effects of 5 days of dry immersion in 20 healthy male subjects, and to obtain DI-in-Men Reference Dataset. A set of measurements will assess the changes in the cardiovascular, neuro-ophthalmological, hematological, metabolic, sensorimotor, immune, muscle and bone systems.
Dry immersion (DI) is a ground-based model of prolonged conditions of simulated microgravity. Dry immersion involves immersing the subject in water covered with an elastic waterproof fabric. As a result, the immersed subject, who is freely suspended in the water mass, remains dry. Within a relatively short duration, the model can faithfully reproduce most physiological effects of actual microgravity, including centralization of body fluids, support unloading, and hypokinesia. The objective of the study is to evaluate the physiological changes induced by 5 days of dry immersion in the female organism. The main physiological systems will be explored before, during and after the 5 days of immersion through a battery of specific tests and measurements. The results will be analyzed by scientists specializing in each field in order to better understand the dry immersion model, to compare its effects with those of the bedrest model and those of spaceflight. The clinical (adverse effects, comfort of subjects) and operational aspects are also part of the secondary objectives of the study.
When astronauts return from space flight, they manifest a set of symptoms, the most striking of which is orthostatic intolerance, that is, the inability to stay upright. This orthostatic intolerance is related to cardiovascular adaptation and disappears in a few days, but the prospect of long-term space travel makes this maladaptation a major concern of space agencies, at a time when there is serious consideration to make " land "a ship on Mars. Previous studies suggest that brain vessel adaptation may contribute to spatial post-flight orthostatic intolerance. The question remains controversial because not all studies are consistent. These studies are all based on the measurement of blood flow in a single artery of the brain (the average cerebral, see cerebral circulation diagram) easily accessible with a Doppler ultrasound machine. Our team has good reason to believe that the adaptation of the cerebral vessels is not carried out in the same way in all the arteries of the brain and that in particular the arteries that irrigate the posterior and inferior parts of the brain are a major determinant. from cerebrovascular adaptation to orthostatism and that orthostatic intolerance is more specifically related to a decrease in blood flow in these arteries. On the other hand our team has shown that the external carotid artery plays, under certain conditions, a buffer role of the sudden variations of perfusion pressure of the brain. During the weightless phase of parabolic flight, part of the blood from the legs and abdomen "rises" to the thorax and this transfer of fluid induces changes in blood pressure and cardiac output that affect the cerebral circulation. From a cardiovascular point of view, it is the same thing for a seated subject to lie down, but the parabolic flight offers the unique possibility of achieving this transfer in a fraction of a second and thus allowing to study the immediate response of the cerebral circulation. . Investigators goal is therefore to quantify the changes in blood flow in the posterior and anterior territories of the brain (transcranial ultrasound) as well as in the internal carotid and vertebral (Doppler ultrasound) during changes in blood pressure and cardiac output induced by transfers. liquid resources associated with the transition to weightlessness. The oxidative stress generated by weightlessness has been identified as a determining factor in cerebrovascular deconditioning associated with orthostatic intolerance. In order to quantify the biochemical markers of this stress, a venous sample will be taken before and just after the parabolic flight.
The objective of the study is to investigate whether thigh cuffs help to prevent and/or reduce the deconditioning induced by 5 days of dry immersion and in particular the fluid shift and its related ophthalmological disorders. During a randomized 5 day dry-immersion study in 20 healthy male adults the two following aims will be undertaken: - Ten scientific protocols will assess the changes in the cerebral, ocular, cardiovascular, metabolism, cognitive, muscle and bone systems. - In the above mentioned systems, the potential beneficial effects of the countermeasure protocol will also be investigated.
The objective of this study is to investigate whether the cocktail of natural antioxidants XXS-2A-BR2 comprising vitamin E and coupled with omega-3 helps to prevent and / or reduce the deleterious effects induced by long term physical inactivity through antiorthostatic bedrest. During a randomized 60 day bed rest study in 20 healthy male adults the two following aims will be undertaken: - Sixteen scientific protocols will assess the changes in the cardiovascular, metabolism, muscle, bone, neuro sensorial, hematological and immunology systems. - In the above mentioned systems, the potential beneficial effects of the countermeasure protocol will also be investigated.
This study is a collaboration between the Centre of Human & Aerospace Physiological Sciences (CHAPS) and the Sleep and Brain Plasticity Centre (Department of Neuroimaging) at King's College London and the Sleep Disorders Centre at Guy's Hospital.The main purpose of the study is to evaluate the effects of a 7 day unloading period (simulating micro gravity) on muscle mass using three independent methods; two scanning techniques (magnetic resonance imaging (MRI) and dual x-ray absorptiometry (DXA)) and one that involves swallowing a capsule that contains a harmless chemical called creatine (D3-Creatine (D3-cr)) and then measuring its concentration in urine. In order to induce muscle loss, participants will be required to lie flat on their back on a water bed filled with water and salt (called hyper-buoyancy flotation (HBF)). As this situation is similar to that experienced in space, the investigators will also measure the effect of HBF on sleep, brain and physiological function - all things known to change in astronauts. Sixteen male subjects (18-40 yrs) will be recruited to participate in the study that will require physiological testing before, during and following both 7 days of normal conditions and 7 days of HBF bed-rest. Each subject will be exposed to the same conditions and assessments over the study period. As some loss of muscle is expected, participants will be offered an exercise rehabilitation programme upon completion of HBF with self-monitored and/or guided sessions based on those provided by the Space Medicine Office of the European Space Agency to returning astronauts.
To investigate the changes of cardiovascular function during short-term simulated weightlessness after electroacupuncture (EA) treatment．
Space flight simulation study to study effects of microgravity through bedrest coupled with flight exercise counter-measures.