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Effects of gravity on humans

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
Na-Ping Tang, Tao-Tao Hui, Jing Ma, Qi-Bing Mei
Recent studies have shown that microRNA (miRNAs) can play important roles in the regulation of endothelial cell (EC) function. However, the expression profile of miRNAs and their effects on the apoptosis of ECs under microgravity conditions remains unclear. In this study, the apoptosis of human pulmonary microvascular endothelial cells (HPMECs) under simulated microgravity was identified by Annexin V and propidium iodide double staining and transmission electron microscopy. miRNA microarray assay was used to screen the differentially expressed miRNAs in HPMECs under simulated microgravity, and eight differentially expressed miRNAs were identified...
September 14, 2018: Journal of Cellular Biochemistry
Jerome Carpenter, Suzanne E Lynch, Jeremy A Cribb, Schuyler Kylstra, David B Hill, Richard Superfine
Mucociliary clearance (MCC) plays an essential role in maintaining airway sterility and health. Conversely, mucociliary dysfunction is implicated across many airway obstructive diseases. Understanding the necessary requirements for successful MCC is imperative to establish the pathology of disease as well as to develop therapeutic strategies. Although gravitational drainage is used clinically via postural drainage to aid mucus clearance, it is ignored in both animal and cell culture models of MCC. In this study we develop a novel mucus clearance assay that enables the first particle image velocimetry of human bronchial epithelial cell cultures tilted relative to the gravitational field...
September 13, 2018: American Journal of Physiology. Lung Cellular and Molecular Physiology
Daniel R Hirmas, Daniel Giménez, Attila Nemes, Ruth Kerry, Nathaniel A Brunsell, Cassandra J Wilson
Soil macroporosity affects field-scale water-cycle processes, such as infiltration, nutrient transport and runoff1,2 , that are important for the development of successful global strategies that address challenges of food security, water scarcity, human health and loss of biodiversity3 . Macropores-large pores that freely drain water under the influence of gravity-often represent less than 1 per cent of the soil volume, but can contribute more than 70 per cent of the total soil water infiltration4 , which greatly magnifies their influence on the regional and global water cycle...
September 2018: Nature
Cora S Thiel, Svantje Tauber, Swantje Christoffel, Andreas Huge, Beatrice A Lauber, Jennifer Polzer, Katrin Paulsen, Hartwin Lier, Frank Engelmann, Burkhard Schmitz, Andreas Schütte, Christiane Raig, Liliana E Layer, Oliver Ullrich
The gravitational force has been constant throughout Earth's evolutionary history. Since the cell nucleus is subjected to permanent forces induced by Earth's gravity, we addressed the question, if gene expression homeostasis is constantly shaped by the gravitational force on Earth. We therefore investigated the transcriptome in force-free conditions of microgravity, determined the time frame of initial gravitational force-transduction to the transcriptome and assessed the role of cation channels. We combined a parabolic flight experiment campaign with a suborbital ballistic rocket experiment employing the human myelomonocytic cell line U937 and analyzed the whole gene transcription by microarray, using rigorous controls for exclusion of effects not related to gravitational force and cross-validation through two fully independent research campaigns...
September 5, 2018: Scientific Reports
Ivanna V Sakhanda, Kostyantyn L Kosyachenko
OBJECTIVE: Introduction: Medicinal plants are an effective means of prevention of many cardiovascular diseases in high-risk groups. Also, they are often used as a means of adjuvant therapy. Centuries of experience in the use of medicinal plants in folk medicine is the result of their relatively high efficiency and their wide distribution in natural ecosystems, and sometimes close to human habitation. The aim of this work is to study the assortment of herbal medicinal products and to consider examples of the basic methods of treatment of cardiovascular diseases with medicinal plants...
2018: Wiadomości Lekarskie: Organ Polskiego Towarzystwa Lekarskiego
Anne G Hoen, Juliette C Madan, Zhigang Li, Modupe Coker, Sara N Lundgren, Hilary G Morrison, Thomas Palys, Brian P Jackson, Mitchell L Sogin, Kathryn L Cottingham, Margaret R Karagas
Arsenic is a ubiquitous environmental toxicant with antimicrobial properties that can be found in food and drinking water. The influence of arsenic exposure on the composition of the human microbiome in US populations remains unknown, particularly during the vulnerable infant period. We investigated the relationship between arsenic exposure and gut microbiome composition in 204 infants prospectively followed as part of the New Hampshire Birth Cohort Study. Infant urine was analyzed for total arsenic concentration using inductively coupled plasma mass spectrometry...
August 22, 2018: Scientific Reports
Zeynep Masatli, Michael Nordine, Martina A Maggioni, Stefan Mendt, Ben Hilmer, Katharina Brauns, Anika Werner, Anton Schwarz, Helmut Habazettl, Hanns-Christian Gunga, Oliver S Opatz
Cardiovascular deconditioning occurs in astronauts during microgravity exposure, and may lead to post-flight orthostatic intolerance, which is more prevalent in women than men. Intermittent artificial gravity is a potential countermeasure, which can effectively train the cardiovascular mechanisms responsible for maintaining orthostatic integrity. Since cardiovascular responses may differ between women and men during gravitational challenges, information regarding gender specific responses during intermittent artificial gravity exposure plays a crucial role in countermeasure strategies...
2018: Frontiers in Physiology
Ievgen Levadnyi, Jan Awrejcewicz, Yan Zhang, Márcio Fagundes Goethel, Yaodong Gu
This study investigated the influence of human head impact on the severity of traumatic brain injury. Simulation of the dynamic impact of a human head was performed using FEM (finite element method) and employing HIC (Head Injury Criterion). The study of traumatic brain injury included impacts with the occiput, temporal, forehead, and parietal part of the head, and the impact velocity at the surface ranged from 1 to 7 m/s. The following characteristics were considered and analyzed in the simulation: duration of the impact, intracranial pressure, HIC, and change in accelerations at the center of gravity of the brain...
2018: Journal of Medical and Biological Engineering
Alex S Huang, Rafaella C Penteado, Sajib K Saha, Jian L Do, Phillip Ngai, Zhihong Hu, Robert N Weinreb
PURPOSE: To evaluate aqueous humor outflow (AHO) in intact eyes of live human subjects during cataract surgery using fluorescein aqueous angiography. METHODS: Aqueous angiography was performed in 8 live human subjects (56 - 86▒y old; 2 men and 6 women). After anesthesia, fluorescein (2%) was introduced into the eye (either alone or after indocyanine green [ICG; 0.4%]) from a sterile, gravity-driven constant-pressure reservoir. Aqueous angiographic images were obtained with a Spectralis HRA+OCT and FLEX module (Heidelberg Engineering)...
August 7, 2018: Journal of Glaucoma
Ying I Wang, Michael L Shuler
Microphysiological systems, also known as body-on-a-chips, are promising "human surrogates" that may be used to evaluate potential human response to drugs in preclinical drug development. Various microfluidics-based platforms have been proposed to interconnect different organ models and provide perfusion in mimicking the blood circulation. We have previously developed a pumpless platform that combines gravity-driven fluid flow and a rocking motion to create reciprocating flow between reservoirs for recirculation...
August 21, 2018: Lab on a Chip
Zachary Ray, Erik D Engeberg
Autonomously preventing grasped objects from slipping out of prosthetic hands is an important feature for limb-absent people since they cannot directly feel the grip force applied to grasped objects. Oftentimes, a satisfactory grip force in one situation will be inadequate in different situations, such as when the object is rotated or transported. Over time, people develop a grip reflex to prevent slip of grasped objects when they are rotated with respect to gravity by their natural hands. However, this reflexive trait is absent in commercially available prosthetic hands...
2018: Journal of Healthcare Engineering
Salman Faraji, Amy R Wu, Auke J Ijspeert
Since the advent of energy measurement devices, gait experiments have shown that energetic economy has a large influence on human walking behavior. However, few cost models have attempted to capture the major energy components under comprehensive walking conditions. Here we present a simple but unified model that uses walking mechanics to estimate metabolic cost at different speeds and step lengths and for six other biomechanically-relevant gait experiments in literature. This includes at various gait postures (e...
July 20, 2018: Scientific Reports
Dan Xu, Yu-Bing Guo, Min Zhang, Ye-Qing Sun
PURPOSE: Microgravity is known to cause endothelium dysfunction in astronauts returning from spaceflight. We aimed to reveal the regulatory mechanism in alterations of human endothelial cells after simulated microgravity (SMG). METHODS: We utilized the rotary cell culture system (RCCS-1) to explore the subsequent effects of SMG on human umbilical vein endothelial cells (HUVECs). RESULTS: SMG-treated HUVECs appeared obvious growth inhibition after return to normal gravity, which might be attributed to a set of responses including alteration of cytoskeleton, decreased cell adhesion capacity and increased apoptosis...
August 2018: Chinese Journal of Traumatology, Zhonghua Chuang Shang za Zhi
Taghi Ramazanian, Julia A Müller-Lebschi, Min Yao Chuang, Anthony M Vaichinger, James S Fitzsimmons, Shawn W O'Driscoll
BACKGROUND: Long-term radiographic arthritis has been commonly reported after radial head excision. Concern over radial head arthroplasty may arise in certain situations including capitellar arthritis, radiocapitellar malalignment, and in young and active patients. We hypothesized that radial head excision increases coronoid contact pressures, which may at least be partially reduced by radiocapitellar Achilles tendon disc arthroplasty. METHODS: Coronoid and capitellar contact pressure was measured on 6 human cadaveric elbows on a custom-designed gravity-valgus simulator under passive flexion from 0° to 90°...
July 11, 2018: Journal of Shoulder and Elbow Surgery
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