Gravity sensing in plant and animal cells

Gravity determines shape of body tissue and affects the functions of life, both in plants and animals. The cellular response to gravity is an active process of mechanotransduction. Although plants and animals share some common mechanisms of gravity sensing in spite of their distant phylogenetic origin, each species has its own mechanism to sense and respond to gravity. In this review, we discuss current understanding regarding the mechanisms of cellular gravity sensing in plants and animals. Understanding gravisensing also contributes to life on Earth, e.g., understanding osteoporosis and muscle atrophy. Furthermore, in the current age of Mars exploration, understanding cellular responses to gravity will form the foundation of living in space

Industrial Heritage Assessment and Guidelines for the Architectural Conservation of Hydroelectric Plants

Hydroelectric plants, constructed as modern, industrial, innovative and technological structures of the 20th century, after approximately a century of existence, have become subjects of industrial heritage. Within the article, the interdisciplinary field is approached through the perspective of architectural conservation with consultancies of experts from related disciplines. The study discusses hydroelectric facilities of the past century in terms of industrial heritage focusing on their features, types and elements, investigates the theoretical framework in order to specify criteria for their assessment as cultural heritage, and develops a guideline for the architectural preservation, conservation, restoration and re-use of these structures. The proposed set of criteria and the guideline are applied for 17 selected case studies of dams and powerhouses in Northern Italy. The process and the results of the study are discussed with a purpose of serving as a model for further studies on the preservation, conservation and restoration of hydroelectric plants

Using Tactile Pressure Sensors to Measure Lateral Spreading Induced Earth Pressures Against a Large, Rigid Foundation

Two centrifuge tests were performed at the NEES facility at Rensselaer Polytechnic Institute (RPI) to observe lateral earth pressures mobilized against a rigid foundation element during liquefaction-induced lateral spreading, as part of a larger NEESR study aimed at developing novel approaches to mitigate the effects of seismically-induced ground failures on large, rigid foundation elements. Models were constructed in a laminar box to allow unimpeded downslope soil displacement, and the sand in the model was liquefied during the centrifuge test. Lateral pressures prior to, during, and after shaking and liquefaction were directly measured using a novel device: tactile pressure sensors. Prior to testing the production models, several 1g and centrifuge experiments were conducted to determine whether the tactile pressure sensors would accurately measure pressures. Using the tactile pressure sensor and configuration described in this paper, geostatic pressures measured prior to the shaking agreed well with the anticipated theoretical at-rest earth pressures. In this paper, we describe these initial tests, the challenges that were encountered, methods employed to overcome these challenges, and the production centrifuge tests

Space explorers need to be space farmers : what we know and what we need to know about plant growth in space

Space exploration will require life support systems, in which plants can provide nutrients, oxygen, moisture, and psychological well-being and eliminate wastes. In alien environments, plants must adapt to a different gravity force, even the zero gravity of spaceflight. Under these conditions, essential cellular and molecular features related to plant development are altered and changes in gene expression occur. In lunar gravity, the effects are comparable to microgravity, while the gravity of Mars produces milder alterations. Nevertheless, it has been possible to develop and reproduce plants in space. Current research seeks to identify signals replacing gravity for driving plant growth, such as light. Counteracting gravitational stress will help in enabling agriculture in extraterrestrial habitats

Inclination not force is sensed by plants during shoot gravitropism

International audienceGravity perception plays a key role in how plants develop and adapt to environmental changes. However, more than a century after the pioneering work of Darwin, little is known on the sensing mechanism. Using a centrifugal device combined with growth kinematics imaging, we show that shoot gravitropic responses to steady levels of gravity in four representative angiosperm species is independent of gravity intensity. All gravitropic responses tested are dependent only on the angle of inclination from the direction of gravity. We thus demonstrate that shoot gravitropism is stimulated by sensing inclination not gravitational force or acceleration as previously believed. This contrasts with the otolith system in the internal ear of vertebrates and explains the robustness of the control of growth direction by plants despite perturbations like wind shaking. Our results will help retarget the search for the molecular mechanism linking shifting statoliths to signal transduction

Molecular response of Deinococcus radiodurans to simulated microgravity explored by proteometabolomic approach

Regarding future space exploration missions and long-term exposure experiments, a detailed investigation of all factors present in the outer space environment and their effects on organisms of all life kingdoms is advantageous. Influenced by the multiple factors of outer space, the extremophilic bacterium Deinococcus radiodurans has been long-termly exposed outside the international Space Station in frames of the tanpopo orbital mission. the study presented here aims to elucidate molecular key components in D. radiodurans, which are responsible for recognition and adaptation to simulated microgravity. D. radiodurans cultures were grown for two days on plates in a fast-rotating 2-D clinostat to minimize sedimentation, thus simulating reduced gravity conditions. Subsequently, metabolites and proteins were extracted and measured with mass spectrometry-based techniques. our results emphasize the importance of certain signal transducer proteins, which showed higher abundances in cells grown under reduced gravity. these proteins activate a cellular signal cascade, which leads to differences in gene expressions. Proteins involved in stress response, repair mechanisms and proteins connected to the extracellular milieu and the cell envelope showed an increased abundance under simulated microgravity. focusing on the expression of these proteins might present a strategy of cells to adapt to microgravity conditions

The Rationale of Autologously Prepared Bone Marrow Aspirate Concentrate for use in Regenerative Medicine Applications

Autologously prepared bone marrow aspirate concentrates, have the potential to play an adjunctive role in various patient pathologies that have not been able to heal with conventional treatment modalities. The use of bone marrow aspirate (BMA) and concentrates in regenerative medicine treatment plans and clinical applications is based on the fact that bone marrow cells, including progenitor and nucleated cells, platelets, and other cytokines, support in tissue healing and tissue regenerative processes. The use of concentrated BMA cells focuses primarily on mesenchymal stem cells (MSCs), with the ability to self-renew and differentiate into multiple cell types. Concentrated bone marrow cells can be retrieved from harvested BMA and ensuing minimal manipulative cell processing techniques, executed at point of care (POC). The application of bone marrow biological therapies may offer solutions in musculoskeletal pathologies, spinal disorders, chronic wound care, and critical limb ischemia (CLI), to effectively change the local microenvironment to support in tissue healing and facilitate tissue regeneration. This chapter will address the cellular content of bone marrow tissue, harvesting and preparation techniques, and discuss the biological characteristics of individual marrow cells, their inter-connectivity, and deliberate on the effects of BMA concentration

Role of Drug Repurposing in Cancer Treatment and Liposomal Approach of Drug Targeting

Cancer is the leading cause of death, and incidences are increasing significantly and patients suffering from it desperately need a complete cure from it. The science of using an already-invented drug that has been approved by the FDA for a new application is known as “drug repurposing.” Currently, scientists are drawn to drug repositioning science in order to investigate existing drugs for newer therapeutic uses and cancer treatment. Because of their unique ability to target cancer cells, recently repurposed drugs and the liposomal approach are effective in the treatment of cancer. Liposomes are nanovesicles that are drastically flexible, rapidly penetrate deeper layers of cells, and enhance intracellular uptake. More importantly, liposomes are biocompatible, biodegradable; entrap both hydrophobic and hydrophilic drugs. This chapter summarizes various approaches to drug repurposing, as well as drug repurposing methods, advantages and limitations of drug repurposing, and a liposomal approach to using repurposed drugs in cancer targeting. This chapter also summarizes liposomal structure, drug loading, and the mechanism of liposomes in targeted cancer treatment. The lipid-based liposomal approach is emerging as a powerful technique for improving drug solubility, bioavailability, reducing side effects, and improving the therapeutic efficacy of repurposed drugs for cancer treatment

The Effect of Gravity on the Nervous System

Gravity affects the nervous system of living organisms. This book chapter reviews historical and recent findings on how changes in gravity affect cellular and subcellular parameters of human and animal cells as well as the timing and shaping of complex sensorimotor responses. With an emphasize on weightlessness, partial, and hypergravity conditions, the gravity dependencies of living organisms have been manifested on different levels of organization, ranging from changes in biophysical properties of single cells to the intact nervous system. An effort has been made to integrate the various findings into a consistent model for a better understanding of how the components of the nervous system interact as a response to acute and long-term gravitational variation. Especially with planned long-term manned missions to Mars and beyond, knowledge about the impact of increased and decreased gravity on the nervous system is essential for the physical and cognitive preparation to assure the success of space missions and human survival in space