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Glossary of scientific and technical terms in bioengineering and biological engineering
Published in Megh R. Goyal, Scientific and Technical Terms in Bioengineering and Biological Engineering, 2018
Progenitor cell is progenitor cell, often confused with stem cell, is an early descendant of a stem cell that can only differentiate, but it cannot renew itself anymore. In contrast, a stem cell can renew itself (make more stem cells by cell division) or it can differentiate (divide and with each cell division evolve more and more into different types of cells). A progenitor cell is often more limited in the kinds of cells it can become than a stem cell. In scientific terms, it is said that progenitor cells are more differentiated than stem cells.
Tissue engineering and regenerative medicine
Published in Ronald L. Fournier, Basic Transport Phenomena in Biomedical Engineering, 2017
In addition to stem cells, there are also what are known as progenitor cells, which are further along in the differentiation process than a stem cell. Progenitor cells reside in all kinds of tissues found in the body. Under the right conditions, progenitor cells can differentiate into a more specific cell type; however, they cannot replicate indefinitely like a stem cell. When presented with the proper signals, progenitor cells can therefore replace those cells that are lost as a result of injury or through normal attrition.
Use of Nanotechnology for Viable Applications in the Field of Medicine
Published in T. S. Srivatsan, T. S. Sudarshan, K. Manigandan, Manufacturing Techniques for Materials, 2018
Mazaher Gholipourmalekabadi, Mohammad Taghi Joghataei, Aleksandra M. Urbanska, Behzad Aghabarari, Aidin Bordbar-Khiabani, Ali Samadikuchaksaraei, Masuod Mozafari
Tissue engineering (also known as regenerative medicine) is a field of research that aims to develop biological substitutes to repair damaged tissues and restore their functionality using a triad of biomaterial scaffolds and soluble factors in combination with cells (i.e., stem cells), [14,23,25–28]. The use of stem and progenitor cells has opened a new frontier in regenerative medicine. Stem cells are undifferentiated cells endowed with a capacity for self-renewal, as well as clonogenic and multilineage differentiation [29,30]. These cells can be differentiated to at least two different cell lines and have a high capacity in tissue engineering applications [29,31]. Embryonic stem cells (ESCs) are pluripotent stem cells derived from the inner cell mass of a blastocyst at an early-stage embryo. Adult stem cells, such as hematopoietic, mesenchymal stem cells, are also multipotent stem cells that present in bone marrow, periphery blood, and other tissues. Stem cell behavior is often correlated with cues that lie in an extracellular microenvironment. It is known that stem cells can respond to genetic signals, such as those imparted by nucleic acids, for the purpose of promoting lineage-specific differentiation. However, before they achieve therapeutic relevancy, proper methods need to be developed to control stem cell differentiation [29,32,33]. Maintenance of stem cells in undifferentiated stages, directing stem cells to differentiate into a special cell line, and prevention of undesired differentiation and delivery of cells into a specific tissue are important objects for using these cells in tissue engineering [34,35]. Many attempts have been made to consider these subjects. For example, ESCs have been cultured in various conditions: feeder layer (usually fetal mouse fibroblasts) [36] or feeder-free condition using Matrigel or laminin [37], conditioned medium or supplement media using specific molecular factors, such as the leukemia inhibitory factor, to be kept in an undifferentiated stage [38]. These methods have some disadvantages: (1) laborious, (2) need enzymatic or mechanical treatment, (3) time consuming and tedious, (4) need an expert operator, and (5) increase the risk of contamination with animal pathogens. Therefore, these limitations made researchers to set up an ideal method for the purpose of solving them. Many strategies such as encapsulation have been adopted to keep stem cells in undifferentiated stages over several passages and deliver cells into a tissue [36,37,39–41]; this will be described in Section 13.2.1.
The individual and combined effects of spaceflight radiation and microgravity on biologic systems and functional outcomes
Published in Journal of Environmental Science and Health, Part C, 2021
Jeffrey S. Willey, Richard A. Britten, Elizabeth Blaber, Candice G.T. Tahimic, Jeffrey Chancellor, Marie Mortreux, Larry D. Sanford, Angela J. Kubik, Michael D. Delp, Xiao Wen Mao
Tissue regeneration is both a highly mechanosensitive and radiosensitive process, relying heavily on mechanical cues imposed by Earth’s gravity205 and protection by the magnetosphere from harmful ionizing radiation. Data obtained from spaceflight experiments have documented the extensive effects of spaceflight stressors on progenitor cell populations and stem cell differentiation capabilities. These cellular changes often propagate into physiological defects which may pose significant health risks to astronauts both during and after sustained spaceflight missions. This section focuses on stem cell responses across physiologic systems, primarily through the use of both ground-based HLU models, but also simulated microgravity devices (e.g., rotary cell culture systems, rotating wall vessels, and 3D clinostats).
Consequences of space radiation on the brain and cardiovascular system
Published in Journal of Environmental Science and Health, Part C, 2021
Catherine M. Davis, Antiño R. Allen, Dawn E. Bowles
The hippocampal formation undergoes structural changes throughout the human lifespan. It is capable of dramatic reorganization, enabling environmental stimuli to impose functional and structural changes on the brain.7 The plasticity of neuronal connections functions through the generation of new neurons and synapses, which enables the brain to store memories.8 Neurogenesis is defined as the series of developmental steps that lead from the division of a neural stem or progenitor cell to a mature, functionally integrated neuron.9 The generation of new neurons from neural stem cells occurs in only two areas of the adult brain: the subventricular zone (SVZ) of the lateral ventricles and the subgranular zone (SGZ) of the DG in the hippocampus.7 In mammals, precursor cell proliferation occurs in the SGZ throughout life,10,11 resulting in newly born cells that are capable of migrating into the dentate granule cell layer.11 Newborn granule cells pass through several developmental steps, from a dividing progenitor to a mature granule cell that is indistinguishable from granule cells born during embryonic development.12 They develop granule cell morphology, then become functionally integrated into the local circuitry13 and have action potentials and functional synaptic inputs14 about 4 weeks after division.
Effects of ambient particulate matter on vascular tissue: a review
Published in Journal of Toxicology and Environmental Health, Part B, 2020
Kristina Shkirkova, Krista Lamorie-Foote, Michelle Connor, Arati Patel, Giuseppe Barisano, Hans Baertsch, Qinghai Liu, Todd E. Morgan, Constantinos Sioutas, William J. Mack
In elderly Los Angeles residents, elevated markers of airway inflammation (FeNO) and oxidative stress (malondialdehyde (MDA)) were associated with PM0.18, transition metals, and traffic-derived air pollutants, including black carbon (BC), carbon monoxide (CO), and nitrogen oxides (NOx) (Zhang et al. 2016a). Reactive hyperemia index was inversely correlated with ambient PM2.5, BC, NOx, and CO. Zhang et al. (2016b), in a similar cohort, detected altered microvascular endothelial function, characterized by the reactive hyperemia index of the brachial artery inversely associated with traffic-related pollutant exposure (PM2.5, BC, NOx, CO) and other mobile-source components and tracers with high oxidative potential. Combined house dust (PM2.5 concentration of 275 μg/m3) and ozone (100 ppb) exposure enhanced ROS production capacity in granulocytes and monocytes (Jantzen et al. 2018). Following exposure, CD34+KDR+ late endothelial progenitor cell number decreased by 48% in the blood of elderly individuals. Exposure data were collected from central monitoring stations, which may introduce measurement error. Individual diets were not recorded, a potential confounding factor influencing vascular function. A controlled human exposure study demonstrated increased levels of urinary 8-OHdG in healthy nonsmoking adults exposed to coarse (2.5–10 μm) or ultrafine concentrated ambient particles (CAPs) (< 0.3 μm). Urinary MDA levels were elevated in those exposed to fine CAPs (0.15–2.5 μm) (Liu et al. 2015).