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Effects of gravity on humans

Tobias Weber, David A Green, Julia Attias, Wolfram Sies, Alexandre Frechette, Bjoern Braunstein, Jörn Rittweger
Moon and Mars are considered to be future targets for human space explorations. The gravity level on the Moon and Mars amount to 16% and 38%, respectively, of Earth's gravity. Mechanical loading during the anticipated habitual activities in these hypogravity environments will most likely not be sufficient to maintain physiological integrity of astronauts unless additional exercise countermeasures are performed. Current microgravity exercise countermeasures appear to attenuate but not prevent 'space deconditioning'...
2019: PloS One
Shan Lateef, Aubrie Holman, Jessica Carpenter, Jennifer James
Background/main objectives: No effective strategy exists to treat the well-recognized, devastating impact of traumatic brain injury (TBI) and chronic traumatic encephalopathy (CTE), which is the brain degeneration likely caused by repeated head trauma. The goals of this project were (1) to study the effects of single and recurrent TBI (rTBI) on Drosophila melanogaster's (a) life span, (b) response to sedatives, and (c) behavioral responses to light and gravity and (2) to determine whether therapeutic hypothermia can mitigate the deleterious effects of TBI...
2019: Journal of Experimental Neuroscience
Eleonora Grigoryan, Elena Radugina
We summarize data from our experiments on stem-like cell dependent regeneration in amphibians in microgravity. Considering its deleterious effect on many tissues, we asked whether microgravity is compatible with reparative processes, specifically activation and proliferation of source cells. Experiments were conducted using tailed amphibians, which combine profound regenerative capabilities with high robustness, allowing in vivo study of lens, retina, limb and tail regeneration in challenging settings of spaceflight...
January 30, 2019: Stem Cells and Development
G Kim Prisk
Purpose of Review: The challenges presented to the lung by the space environment are the effects of prolonged absence of gravity, the challenges of decompression stress associated with spacewalking, and the changes in the deposition of inhaled particulate matter. Recent Findings: Although there are substantial changes in the function of the lung in partial gravity, the lung is largely unaffected by sustained exposure, returning rapidly to a normal state after return to 1G...
September 2018: Current Pathobiology Reports
Robert-Andrei Voicu, Ciprian Dobre, Lidia Bajenaru, Radu-Ioan Ciobanu
Because the number of elderly people is predicted to increase quickly in the upcoming years, "aging in place" (which refers to living at home regardless of age and other factors) is becoming an important topic in the area of ambient assisted living. Therefore, in this paper, we propose a human physical activity recognition system based on data collected from smartphone sensors. The proposed approach implies developing a classifier using three sensors available on a smartphone: accelerometer, gyroscope, and gravity sensor...
January 23, 2019: Sensors
Barbara La Scaleia, Francesco Lacquaniti, Myrka Zago
KEY POINTS: It is known that interception of targets accelerated by gravity involves internal models coupled with visual signals. Nonvisual signals related to head and body orientation relative to gravity may also contribute, but their role is poorly understood. In a novel experiment, we asked pitched observers to hit a virtual target approaching with an acceleration that was either coherent or incoherent with their pitch-tilt. Initially, the timing errors were large and independent of the coherence between target acceleration and observer's pitch...
January 15, 2019: Journal of Physiology
Frank Meyer, John Humm, Yuvaraj Purushothaman, Rémy Willinger, Frank A Pintar, Narayan Yoganandan
Experiments have been conducted using isolated tissues of the spine such as ligaments, functional units, and subaxial cervical spine columns. Forces and or moments under external loading can be obtained at the ends of these isolated/segmented preparations; however, these models require fixations at the end(s). To understand the response of the entire cervical spine without the artificial boundary/end conditions, it is necessary to use the whole body human cadaver in the experimental model. This model can be used to obtain the overall kinematics of the head and neck...
October 2, 2018: Journal of the Mechanical Behavior of Biomedical Materials
Isabel P Alves, Nuno M Reis
This study presents novel experimental insights into the direct quantitation and immunocapture of bacteria cells in a fluoropolymer microcapillary array, using Escherichia coli as work model, a pathogen responsible for around 80% of urinary tract infections (UTIs). In spite of the current clinical demand for sensitive tests for rapid identification and quantitation of pathogens in human samples, portable diagnostic tests developed to date lack the specificity, limit of detection and speed for effective implementation in bacteria detection at point-of-care...
November 24, 2018: Journal of Chromatography. A
Thomas P Swaffield, Andrew S Neviaser, Kris Lehnhardt
INTRODUCTION: Understanding the effects of microgravity on bone is essential, since humans are now considering long-distance spaceflight missions. It is well known that bone mineral density (BMD) decreases during long-duration spaceflight. While the risk of fracture in a microgravity environment is believed to be low, the potential risk for fracture increases upon re-entering a gravity environment. The objective of this study was to determine skeletal regions of high-risk for fracture after long-duration spaceflight and identify management protocols for those fractures...
December 1, 2018: Aerospace Medicine and Human Performance
Justin Fong, Vincent Crocher, Raneem Haddara, David Ackland, Mary Galea, Ying Tan, Denny Oetomo
Deweighting of the limb is commonly performed for patients with a neurological injury, such as stroke, as it allows these patients with limited muscle activity to perform movements. Deweighting has been implemented in exoskeletons and other multi-contact devices, but not on an end-effector based device with single contact point between the assisting robot and the human limb being assisted. This study inves-tigates the effects of deweighting using an end-effector based device on healthy subjects. The muscle activity of five subjects was measured in both static postures and dynamic movements...
July 2018: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Carlo Tiseo, Kalyana C Veluvolu, Ang Wei Tech
The motor control of human locomotion is still an open issue, and it may be the leading cause of the low effectiveness of lower limbs rehabilitation therapies. Locomotion motor control has proved to be fundamentally different from the upper limbs reaching task strategies, which have been used for the development of current motor control computational models used to define rehabilitation protocols. The main difference between these two tasks is the relevance of the environmental dynamics in task planning and execution...
July 2018: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Brett T Doherty, Kate Hoffman, Alexander P Keil, Stephanie M Engel, Heather M Stapleton, Barbara D Goldman, Andrew F Olshan, Julie L Daniels
Organophosphate esters (OPEs) are a class of chemicals commonly used as flame retardants and plasticizers. OPEs are applied to a wide variety of consumer products and have a propensity to leach from these products. Consequently, OPEs are ubiquitous contaminants in many human environments and human exposure is pervasive. Accumulating evidence suggests that OPEs are capable of interfering with childhood cognitive development through both neurologic- and endocrine-mediated mechanisms. However, observational evidence of cognitive effects is limited...
October 30, 2018: Environmental Research
Liang Li, Cui Zhang, Jian-Ling Chen, Fan-Fan Hong, Ping Chen, Jin-Fu Wang
OBJECTIVES: Exposure to microgravity induces many adaptive and pathological changes in human bone marrow mesenchymal stem cells (hBMSCs). However, the underlying mechanisms of these changes are poorly understood. We revealed the gene expression patterns of hBMSCs under normal ground (NG) and simulated microgravity (SMG), which showed an interpretation for these changes by gene regulation and signal pathways analysis. MATERIALS AND METHODS: In this study, hBMSCs were osteogenically induced for 0, 2, 7 and 14 days under normal ground gravity and simulated microgravity, followed by analysis of the differences in transcriptome expression during osteogenic differentiation by RNA sequencing and some experimental verification for these results...
November 5, 2018: Cell Proliferation
Andrea Bellavia, Yu-Han Chiu, Florence M Brown, Lidia Mínguez-Alarcón, Jennifer B Ford, Myra Keller, John Petrozza, Paige L Williams, Xiaoyun Ye, Antonia M Calafat, Russ Hauser, Tamarra James-Todd
BACKGROUND: A number of endocrine disrupting chemicals (EDC) have been associated with gestational diabetes (GDM) risk factors. However, no human study has investigated the association between pregnancy exposure to parabens, a class of EDCs, and pregnancy glucose levels, a risk factor for GDM. Furthermore, little is known about this association in subfertile women-a group at high risk of GDM. METHODS: A total of 241 women from the Environment and Reproductive Health Study had data available on 1st and/or 2nd trimester urinary methylparaben, propylparaben, and butylparaben concentrations, and blood glucose levels after the glucose loading test (GLT), a non-fasting 50 g glucose loading test taken at late 2nd trimester...
October 14, 2018: Environmental Research
Veronika V Malaeva, Vladimir I Korenbaum, Irina A Pochekutova, Anatoly E Kostiv, Svetlana N Shin, Vladimir P Katuntsev, Viktor M Baranov
Estimating the effect of microgravity/hypogravity on pulmonary ventilation function remains topical. Recently developed acoustic techniques based on the evaluation of the forced expiratory noise time (FETa) were hypothesized to be a promising tool for this aim. The aim of the protocol is to study the effect of two different modalities of bed rest space simulations (microgravity and lunar gravity) on FETa and spirometric indices. The FETa in the frequency band of 200-2000 Hz, recorded above human trachea, was evaluated...
2018: Frontiers in Physiology
Silje A Wolff, Carolina F Palma, Leo Marcelis, Ann-Iren Kittang Jost, Sander H van Delden
Long term human missions to the Moon and Mars, rely on life support systems for food production and regeneration of resources. In the EU H2020 TIME SCALE-project, an advanced life support system concept was developed to facilitate plant research and technology demonstration under different gravity conditions. Ground experiments assessed irrigation systems and effects of rooting- and nutrient solution volume. The maximal allowed volume for existing International Space Station research facilities (3.4 L) was able to support cultivation of two lettuce heads for at least 24 days...
October 6, 2018: Life
Dong Wook Lee, Nakwon Choi, Jong Hwan Sung
Perfusion flow is one of the essential elements and advantages of organ-on-a-chip technology. For example, microfluidics have enabled implementation of perfusion flow and recapitulation of fluidic environment for vascular endothelial cells. The most prevalent method of implementing flow in a chip is to use a pump, which requires elaborate manipulation and complex connections, and accompanies a large amount of dead volume. Previously we devised a gravity-induced flow system which does not require tubing connections, but this method results in bidirectional flow to enable recirculation, which is somewhat different from physiological blood flow...
October 7, 2018: Biotechnology Progress
Silvia Martini, Arianna Aceti, Martina Furini, Alessandra Munarini, Cristina La Riccia, Vilma Mantovani, Giacomo Faldella, Luigi Corvaglia
BACKGROUND: Arachidonic acid (AA) and docosahexaenoic acid (DHA) are crucial for neural and visual development after premature birth. Preterm infants usually require tube feeding (TF) until the achievement of adequate oral feeding skills; the impact of TF on DHA and AA delivery has not been investigated yet. This study aimed to evaluate the effect of different TF techniques on the delivery of AA and DHA contained in human milk (HM). METHODS: HM samples (65 mL each) were collected and divided into three 20-mL aliquots...
September 27, 2018: JPEN. Journal of Parenteral and Enteral Nutrition
Svantje Tauber, Swantje Christoffel, Cora Sandra Thiel, Oliver Ullrich
Whereby several types of cultured cells are sensitive to gravity, the immune system belongs to the most affected systems during spaceflight. Since reactive oxygen species/reactive nitrogen species (ROS/RNS) are serving as signals of cellular homeostasis, particularly in the cells of the immune system, we investigated the immediate effect of altered gravity on the transcription of 86 genes involved in reactive oxygen species metabolism, antioxidative systems, and cellular response to oxidative stress, using parabolic flight and suborbital ballistic rocket experiments and microarray analysis...
September 18, 2018: International Journal of Molecular Sciences
James A Dreibelbis, Brooke E Organ
BACKGROUND: Humans detect motion and gravity via the labyrinthine system of the inner ear, which consists of the vestibule and the semicircular canals. The vestibular system provides three major functions for maintaining balance and orientation. First, it maximizes the effectiveness of the visual system. Second, it provides orientational information necessary for performing both skilled and reflexive motor activities. Third, in the absence of vision, the vestibular system provides a reasonably accurate perception of motion and position...
October 1, 2018: Aerospace Medicine and Human Performance
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