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https://www.readbyqxmd.com/read/29147680/coculture-of-meniscus-cells-and-mesenchymal-stem-cells-in-simulated-microgravity
#1
William M Weiss, Aillette Mulet-Sierra, Melanie Kunze, Nadr M Jomha, Adetola B Adesida
Simulated microgravity has been shown to enhance cartilaginous matrix formation by chondrocytes and chondrogenesis of mesenchymal stem cells (MSCs). Similarly, coculture of primary chondrocytes with MSCs has been shown as a strategy to simultaneously retain the differentiated phenotype of chondrocytes and enhance cartilaginous matrix formation. In this study, we investigated the effect of simulated microgravity on cocultures of primary human meniscus cells and adipose-derived MSCs. We used biochemical, qPCR, and immunofluorescence assays to conduct our investigation...
2017: NPJ Microgravity
https://www.readbyqxmd.com/read/29147679/dense-fluidized-granular-media-in-microgravity
#2
Philip Born, Johannes Schmitz, Matthias Sperl
Handling and transport of granular media are inevitably governed by the settling of particles. Settling into a dense state is one of the defining characteristics of granular media, among dissipation and absence of thermal agitation. Hence, settling complicates the adaptation of microscopic theories from atomic, molecular, or colloidal media to granular media. It is desirable to provide experiments in which selectively one of the granular characteristics is tuned to test suitable adaptation of a theory. Here we show that gas fluidization of granular media in microgravity is a suitable approach to achieve steady states closer to thermally agitated systems free of settling...
2017: NPJ Microgravity
https://www.readbyqxmd.com/read/29145128/microgravity-simulation-activates-cdc42-via-rap1gds1-to-promote-vascular-branch-morphogenesis-during-vasculogenesis
#3
Shouli Wang, Zhao Yin, Bei Zhao, Yanmei Qi, Jie Liu, Saum A Rahimi, Leonard Y Lee, Shaohua Li
Gravity plays an important role in normal tissue maintenance. The ability of stem cells to repair tissue loss in space through regeneration and differentiation remains largely unknown. To investigate the impact of microgravity on blood vessel formation from pluripotent stem cells, we employed the embryoid body (EB) model for vasculogenesis and simulated microgravity by clinorotation. We first differentiated mouse embryonic stem cells into cystic EBs containing two germ layers and then analyzed vessel formation under clinorotation...
November 7, 2017: Stem Cell Research
https://www.readbyqxmd.com/read/29142324/an-algorithm-for-the-beat-to-beat-assessment-of-cardiac-mechanics-during-sleep-on-earth-and-in-microgravity-from-the-seismocardiogram
#4
Marco Di Rienzo, Emanuele Vaini, Prospero Lombardi
Seismocardiogram, SCG, is the measure of precordial vibrations produced by the beating heart, from which cardiac mechanics may be explored on a beat-to-beat basis. We recently collected a large amount of SCG data (>69 recording hours) from an astronaut to investigate cardiac mechanics during sleep aboard the International Space Station and on Earth. SCG sleep recordings are characterized by a prolonged duration and wide heart rate swings, thus a specific algorithm was developed for their analysis. In this article we describe the new algorithm and its performance...
November 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29142208/transient-increases-in-intracellular-calcium-and-reactive-oxygen-species-levels-in-tcam-2-cells-exposed-to-microgravity
#5
C Morabito, S Guarnieri, A Catizone, C Schiraldi, G Ricci, M A Mariggiò
The effects of microgravity on functions of the human body are well described, including alterations in the male and female reproductive systems. In the present study, TCam-2 cells, which are considered a good model of mitotically active male germ cells, were used to investigate intracellular signalling and cell metabolism during exposure to simulated microgravity, a condition that affects cell shape and cytoskeletal architecture. After a 24 hour exposure to simulated microgravity, TCam-2 cells showed 1) a decreased proliferation rate and a delay in cell cycle progression, 2) increased anaerobic metabolism accompanied by increased levels of intracellular Ca(2+), reactive oxygen species and superoxide anion and modifications in mitochondrial morphology...
November 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29134681/gravity-constraints-drive-biological-systems-toward-specific-organization-patterns-commitment-of-cell-specification-is-constrained-by-physical-cues
#6
REVIEW
Mariano Bizzarri, Maria Grazia Masiello, Alessandro Giuliani, Alessandra Cucina
Different cell lineages growing in microgravity undergo a spontaneous transition leading to the emergence of two distinct phenotypes. By returning these populations in a normal gravitational field, the two phenotypes collapse, recovering their original configuration. In this review, we hypothesize that, once the gravitational constraint is removed, the system freely explores its phenotypic space, while, when in a gravitational field, cells are "constrained" to adopt only one favored configuration. We suggest that the genome allows for a wide range of "possibilities" but it is unable per se to choose among them: the emergence of a specific phenotype is enabled by physical constraints that drive the system toward a preferred solution...
November 14, 2017: BioEssays: News and Reviews in Molecular, Cellular and Developmental Biology
https://www.readbyqxmd.com/read/29133864/effects-of-microgravity-on-osteoblast-mitochondria-a-proteomic-and-metabolomics-profile
#7
Anna Michaletti, Magda Gioia, Umberto Tarantino, Lello Zolla
The response of human primary osteoblasts exposed to simulated microgravity has been investigated and analysis of metabolomic and proteomic profiles demonstrated a prominent dysregulation of mitochondrion homeostasis. Gravitational unloading treatment induced a decrease in mitochondrial proteins, mainly affecting efficiency of the respiratory chain. Metabolomic analysis revealed that microgravity influenced several metabolic pathways; stimulating glycolysis and the pentose phosphate pathways, while the Krebs cycle was interrupted at succinate-fumarate transformation...
November 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29112678/perception-of-time-in-microgravity-and-hypergravity-during-parabolic-flight
#8
Gilles Clément
We explored the effect of gravity on the accuracy for estimating durations of 3.5, 7, and 14 s. Experiments were performed on board an Airbus A310 during parabolic flights eliciting repeated exposures to short periods of 0, 1, and 1.8 g. Two methods for obtaining duration estimates were used, reproduction and production of duration, in two conditions: a control counting condition and a concurrent reading condition. Simple reaction times were also measured to assess attention. The results showed that the temporal accuracies during the reproduction task in the concurrent reading condition were significantly underestimated in 0 g compared with 1 g...
November 6, 2017: Neuroreport
https://www.readbyqxmd.com/read/29104544/sensorimotor-reorganizations-of-arm-kinematics-and-postural-strategy-for-functional-whole-body-reaching-movements-in-microgravity
#9
Thomas Macaluso, Christophe Bourdin, Frank Buloup, Marie-Laure Mille, Patrick Sainton, Fabrice R Sarlegna, Jean-Louis Vercher, Lionel Bringoux
Understanding the impact of weightlessness on human behavior during the forthcoming long-term space missions is of critical importance, especially when considering the efficiency of goal-directed movements in these unusual environments. Several studies provided a large set of evidence that gravity is taken into account during the planning stage of arm reaching movements to optimally anticipate its consequence upon the moving limbs. However, less is known about sensorimotor changes required to face weightless environments when individuals have to perform fast and accurate goal-directed actions with whole-body displacement...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29081752/multi-system-deconditioning-in-3-day-dry-immersion-without-daily-raise
#10
Steven De Abreu, Liubov Amirova, Ronan Murphy, Robert Wallace, Laura Twomey, Guillemette Gauquelin-Koch, Veronique Raverot, Françoise Larcher, Marc-Antoine Custaud, Nastassia Navasiolava
Dry immersion (DI) is a Russian-developed, ground-based model to study the physiological effects of microgravity. It accurately reproduces environmental conditions of weightlessness, such as enhanced physical inactivity, suppression of hydrostatic pressure and supportlessness. We aimed to study the integrative physiological responses to a 3-day strict DI protocol in 12 healthy men, and to assess the extent of multi-system deconditioning. We recorded general clinical data, biological data and evaluated body fluid changes...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29080356/the-icam-1-expression-level-determines-the-susceptibility-of-human-endothelial-cells-to-simulated-microgravity
#11
L B Buravkova, E G Rudimov, E R Andreeva, A I Grigoriev
Microgravity is a principal risk factor hampering human cardiovascular regulation during space flights. Endothelial dysfunction associated with the impaired integrity and uniformity of the monolayer represents a potential trigger for vascular damage. We characterized the expression profile of the multi-step cascade of adhesion molecules (ICAM-1, VCAM-1, E-selectin, VE-cadherin) in umbilical cord endothelial cells (ECs) after 24 hrs of exposure to simulated microgravity (SMG), pro-inflammatory cytokine TNF-α, and the combination of the two...
October 28, 2017: Journal of Cellular Biochemistry
https://www.readbyqxmd.com/read/29079684/spaceflight-induced-changes-in-white-matter-hyperintensity-burden-in-astronauts
#12
Noam Alperin, Ahmet M Bagci, Sang H Lee
OBJECTIVE: To assess the effect of weightlessness and the respective roles of CSF and vascular fluid on changes in white matter hyperintensity (WMH) burden in astronauts. METHODS: We analyzed prespaceflight and postspaceflight brain MRI scans from 17 astronauts, 10 who flew a long-duration mission on the International Space Station (ISS) and 7 who flew a short-duration mission on the Space Shuttle. Automated analysis methods were used to determine preflight to postflight changes in periventricular and deep WMH, CSF, and brain tissue volumes in fluid-attenuated inversion recovery and high-resolution 3-dimensional T1-weighted imaging...
October 27, 2017: Neurology
https://www.readbyqxmd.com/read/29075198/impacts-of-simulated-weightlessness-by-dry-immersion-on-optic-nerve-sheath-diameter-and-cerebral-autoregulation
#13
Marc Kermorgant, Florian Leca, Nathalie Nasr, Marc-Antoine Custaud, Thomas Geeraerts, Marek Czosnyka, Dina N Arvanitis, Jean-Michel Senard, Anne Pavy-Le Traon
Dry immersion (DI) is used to simulate weightlessness. We investigated in healthy volunteers if DI induces changes in ONSD, as a surrogate marker of intracranial pressure (ICP) and how these changes could affect cerebral autoregulation (CA). Changes in ICP were indirectly measured by changes in optic nerve sheath diameter (ONSD). 12 healthy male volunteers underwent 3 days of DI. ONSD was indirectly assessed by ocular ultrasonography. Cerebral blood flow velocity (CBFV) of the middle cerebral artery was gauged using transcranial Doppler ultrasonography...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29075195/falls-and-fall-prevention-in-older-persons-geriatrics-meets-spaceflight
#14
REVIEW
Nandu Goswami
This paper provides a general overview of key physiological consequences of microgravity experienced during spaceflight and of important parallels and connections to the physiology of aging. Microgravity during spaceflight influences cardiovascular function, cerebral autoregulation, musculoskeletal, and sensorimotor system performance. A great deal of research has been carried out to understand these influences and to provide countermeasures to reduce the observed negative consequences of microgravity on physiological function...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29061459/spaceflight-and-neurosurgery-a-comprehensive-review-of-the-relevant-literature
#15
REVIEW
Christian Swinney, Zain Allison
OBJECT: Spaceflight and the associated gravitational fluctuations may impact various components of the central nervous system. These include changes in intracranial pressure, the spine, and neurocognitive performance. The implications of altered astronaut performance on critical spaceflight missions are potentially significant. The current body of research on this important topic is extremely limited and a comprehensive review has not been published. Herein, the authors address this notable gap, as well as the role of the neurosurgeon in optimizing potential diagnostic and therapeutic modalities...
October 20, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/29056408/effect-of-gravitational-gradients-on-cardiac-filling-and-performance
#16
Kazuaki Negishi, Allen G Borowski, Zoran B Popović, Neil L Greenberg, David S Martin, Michael W Bungo, Benjamin D Levine, James D Thomas
BACKGROUND: Gravity affects every aspect of cardiac performance. When gravitational gradients are at their greatest on Earth (i.e., during upright posture), orthostatic intolerance may ensue and is a common clinical problem that appears to be exacerbated by the adaptation to spaceflight. We sought to elucidate the alterations in cardiac performance during preload reduction with progressive upright tilt that are relevant both for space exploration and the upright posture, particularly the preload dependence of various parameters of cardiovascular performance...
October 19, 2017: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/29054708/semantic-analysis-of-thyroid-cancer-cell-proteins-obtained-from-rare-research-opportunities
#17
Johann Bauer, Daniela Grimm, Erich Gombocz
Research in natural sciences is mainly done by means of experiments. Some of those experiments such as spaceflight-dependent experiments are extremely laborious, complex and expensive. Hence, they often remain rare events with little chances of statistical tests and possibilities of repetition. In order to make each single event as valuable as possible, a sophisticated comparison of experimental data received with the hundreds of millions of computer-stored documents appears necessary. We used results of an earlier study on proteome analysis of microgravity-exposed human thyroid cancer cells, selected twenty proteins which appeared gravity sensitive and investigated whether their change observed in cells under the loss of gravity could cause health problems in astronauts...
October 18, 2017: Journal of Biomedical Informatics
https://www.readbyqxmd.com/read/29053152/heart-in-space-effect-of-the-extraterrestrial-environment-on-the-cardiovascular-system
#18
REVIEW
Richard L Hughson, Alexander Helm, Marco Durante
National space agencies and private corporations aim at an extended presence of humans in space in the medium to long term. Together with currently suboptimal technology, microgravity and cosmic rays raise health concerns about deep-space exploration missions. Both of these physical factors affect the cardiovascular system, whose gravity-dependence is pronounced. Heart and vascular function are, therefore, susceptible to substantial changes in weightlessness. The altered cardiovascular function in space causes physiological problems in the postflight period...
October 20, 2017: Nature Reviews. Cardiology
https://www.readbyqxmd.com/read/29046893/the-measurement-of-the-surface-energy-of-solids-using-a-laboratory-drop-tower
#19
Alfredo Calvimontes
This work presents a technique for the study and measurement of the interfacial energies of solid-liquid-gas systems. The instrument and the evaluation method for the measurements obtained by it, allow the analysis of the energy changes of sessile drops submitted to microgravity. A mathematical model based on the thermodynamic of wetting is applied to evaluate the interfacial energies as a function of the drop shape changes due to the effect of the release of gravitation during the experiment. The presented model bases on the thermodynamic equilibrium of the interfaces and not on the balance of bi-dimensional tensors on the contour line...
2017: NPJ Microgravity
https://www.readbyqxmd.com/read/29046415/skeletal-stiffening-in-an-amphibious-fish-out-of-water-is-a-response-to-increased-body-weight
#20
Andy J Turko, Dietmar Kültz, Douglas Fudge, Roger P Croll, Frank M Smith, Matthew R Stoyek, Patricia A Wright
Terrestrial animals must support their bodies against gravity, while aquatic animals are effectively weightless because of buoyant support from water. Given this evolutionary history of minimal gravitational loading of fishes in water, it has been hypothesized that weight-responsive musculoskeletal systems evolved during the tetrapod invasion of land and are thus absent in fishes. Amphibious fishes, however, experience increased effective weight when out of water - are these fishes responsive to gravitational loading? Contrary to the tetrapod-origin hypothesis, we found that terrestrial acclimation reversibly increased gill arch stiffness (∼60% increase) in the amphibious fish Kryptolebias marmoratus when loaded normally by gravity, but not under simulated microgravity...
October 15, 2017: Journal of Experimental Biology
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