Science.gov

Sample records for biological isru implications

  1. Developing Biological ISRU: Implications for Life Support and Space Exploration

    NASA Technical Reports Server (NTRS)

    Brown, I. I.; Allen, C. C.; Garrison, D. H.; Sarkisova, S. A.; Galindo, C.; Mckay, David S.

    2010-01-01

    Main findings: 1) supplementing very dilute media for cultivation of CB with analogs of lunar or Martian regolith effectively supported the proliferation of CB; 2) O2 evolution by siderophilic cyanobacteria cultivated in diluted media but supplemented with iron-rich rocks was higher than O2 evolution by same strain in undiluted medium; 3) preliminary data suggest that organic acids produced by CB are involved in iron-rich mineral dissolution; 4) the CB studied can accumulate iron on and in their cells; 4) sequencing of the cyanobacterium JSC-1 genome revealed that this strain possesses molecular features which make it applicable for the cultivation in special photoreactors on Moon and Mars. Conclusion: As a result of pilot studies, we propose, to develop a concept for semi-closed integrated system that uses CB to extract useful elements to revitalize air and produce valuable biomolecules. Such a system could be the foundation of a self-sustaining extraterrestrial outpost (Hendrickx, De Wever et al., 2005; Handford, 2006). A potential advantage of a cyanobacterial photoreactor placed between LSS and ISRU loops is the possibility of supplying these systems with extracted elements and compounds from the regolith. In addition, waste regolith may be transformed into additional products such as methane, biomass, and organic and inorganic soil enrichment for the cultivation of higher plants.

  2. The role of synthetic biology for in situ resource utilization (ISRU).

    PubMed

    Montague, Michael; McArthur, George H; Cockell, Charles S; Held, Jason; Marshall, William; Sherman, Louis A; Wang, Norman; Nicholson, Wayne L; Tarjan, Daniel R; Cumbers, John

    2012-12-01

    A persistent presence in space can either be supported from Earth or generate the required resources for human survival from material already present in space, so called "in situ material." Likely, many of these resources such as water or oxygen can best be liberated from in situ material by conventional physical and chemical processes. However, there is one critical resource required for human life that can only be produced in quantity by biological processes: high-protein food. Here, recent data concerning the materials available on the Moon and common asteroid types is reviewed with regard to the necessary materials to support the production of food from material in situ to those environments. These materials and their suitability as feedstock for the biological production of food are reviewed in a broad and general way such that terminology that is often a barrier to understanding such material by interdisciplinary readers is avoided. The waste products available as in situ materials for feasibility studies on the International Space Station are also briefly discussed. The conclusion is that food production in space environments from in situ material proven to exist there is quite feasible.

  3. ISRU Planning for Mars Exploration

    NASA Astrophysics Data System (ADS)

    Elliott, J. O.; Easter, R.; Surampudi, S.; Voecks, G.

    2012-06-01

    Applications for use of ISRU in Mars exploration abound. Technologies being developed today need to be guided by appropriate system, mission and campaign analyses to identify optimal paths to large scale applicability.

  4. Technologies of ISRU/ISMU

    NASA Technical Reports Server (NTRS)

    Ramohalli, Kumar

    1991-01-01

    The objectives of this paper are twofold. One is to unambiguously identify those in situ resource utilization (ISRU) in-situ materials utilization (ISMU) technologies that have matured past the stage of speculation, or uncertainty, and to present as much quantitative data as possible from working hardware. The second objective is to bring to the attention of the concerned authorities the important fact that many of the technologies are sufficiently advanced today to be seriously considered in the planning of space missions. The paper gives a brief overview of ISRU/ISMU from the literature. Next, results obtained from a well-planned set of research activities to promote ISRU/ISMU are quoted. These include some general technologies such as cryo coolers, power modules, and information systems followed by some very specific technologies such as oxygen production on the moon and Mars.

  5. In-Situ Resource Utilization (ISRU) Capability Roadmap Progress Review

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.; Duke, Michael

    2005-01-01

    A progress review on In-Situ Resource Utilization (ISRU) capability is presented. The topics include: 1) In-Situ Resource Utilization (ISRU) Capability Roadmap: Level 1; 2) ISRU Emphasized Architecture Overview; 3) ISRU Capability Elements: Level 2 and below; and 4) ISRU Capability Roadmap Wrap-up.

  6. In-situ Resource Utilization (ISRU) and Lunar Surface Systems

    NASA Technical Reports Server (NTRS)

    Sanders, Jerry; Larson, Bill; Sacksteder, Kurt

    2007-01-01

    This viewgraph presentation reviews the benefits of In-Situ Resource Utilization (ISRU) on the surface of the moon. Included in this review is the commercialization of Lunar ISRU. ISRU will strongly influence architecture and critical technologies. ISRU is a critical capability and key implementation of the Vision for Space Exploration (VSE). ISRU will strongly effects lunar outpost logistics, design and crew safety. ISRU will strongly effect outpost critical technologies. ISRU mass investment is minimal compared to immediate and long-term architecture delivery mass and reuse capabilities provided. Therefore, investment in ISRU constitutes a commitment to the mid and long term future of human exploration.

  7. Social Implications of Biological Education.

    ERIC Educational Resources Information Center

    Grobman, Arnold B.

    Political and social implications of biological research, with particular reference to consequences for education, are discussed in this collection of papers presented at the 1969 convention of the National Association of Biology Teachers. Commentary papers by a panel of three, including at least one high school biology teacher and one expert in…

  8. Social Implications of Biological Education.

    ERIC Educational Resources Information Center

    Grobman, Arnold B.

    Political and social implications of biological research, with particular reference to consequences for education, are discussed in this collection of papers presented at the 1969 convention of the National Association of Biology Teachers. Commentary papers by a panel of three, including at least one high school biology teacher and one expert in…

  9. Overview of Proposed ISRU Technology Development

    NASA Technical Reports Server (NTRS)

    Linne, Diane; Sanders, Jerry; Starr, Stan; Suzuki, Nantel; O'Malley, Terry

    2016-01-01

    ISRU involves any hardware or operation that harnesses and utilizes in-situ resources (natural and discarded) to create products and services for robotic and human exploration: Assessment of physical, mineral chemical, and volatile water resources, terrain, geology, and environment (orbital and local). Production of replacement parts, complex products, machines, and integrated systems from feedstock derived from one or more processed resources. Civil engineering, infrastructure emplacement, and structure construction using materials produced from in situ resources. Radiation shields, landing pads, roads, berms, habitats, etc. Generation and storage of electrical, thermal, and chemical energy with in situ derived materials. Solar arrays, thermal wadis, chemical batteries, etc. ISRU is a disruptive capability: Enables more affordable exploration than todays paradigm. Allows more sustainable architectures to be developed. Understand the ripple effect in the other Exploration Elements: MAV: propellant selection, higher rendezvous altitude (higher DV capable with ISRU propellants). EDL: significantly reduces required landed mass. Life Support: reduce amount of ECLSS closure, reduce trash mass carried through propulsive maneuvers. Power: ISRU drives electrical requirements, reactant and regeneration for fuel cells for landers, rovers, and habitat backup. Every Exploration Element except ISRU has some flight heritage (power, propulsion, habitats, landers, life support, etc.) ISRU will require a flight demonstration mission on Mars before it will be included in the critical path. Mission needs to be concluded at least 10 years before first human landed mission to ensure lessons learned can be incorporated into final design. ISRU Formulation team has generated a (still incomplete) list of over 75 technical questions on more than 40 components and subsystems that need to be answered before the right ISRU system will be ready for this flight demo.

  10. Minimizing Launch Mass for ISRU Processes

    NASA Technical Reports Server (NTRS)

    England, C.; Hallinan, K. P.

    2004-01-01

    The University of Dayton and the Jet Propulsion Laboratory are developing a methodology for estimating the Earth launch mass (ELM) of processes for In-Situ Resource Utilization (ISRU) with a focus on lunar resource recovery. ISRU may be enabling for both an extended presence on the Moon, and for large sample return missions and for a human presence on Mars. To accomplish these exploration goals, the resources recovered by ISRU must offset the ELM for the recovery process. An appropriate figure of merit is the cost of the exploration mission, which is closely related to ELM. For a given production rate and resource concentration, the lowest ELM - and the best ISRU process - is achieved by minimizing capital equipment for both the ISRU process and energy production. ISRU processes incur Carnot limitations and second law losses (irreversibilities) that ultimately determine production rate, material utilization and energy efficiencies. Heat transfer, chemical reaction, and mechanical operations affect the ELM in ways that are best understood by examining the process's detailed energetics. Schemes for chemical and thermal processing that do not incorporate an understanding of second law losses will be incompletely understood. Our team is developing a methodology that will aid design and selection of ISRU processes by identifying the impact of thermodynamic losses on ELM. The methodology includes mechanical, thermal and chemical operations, and, when completed, will provide a procedure and rationale for optimizing their design and minimizing their cost. The technique for optimizing ISRU with respect to ELM draws from work of England and Funk that relates the cost of endothermic processes to their second law efficiencies. Our team joins their approach for recovering resources by chemical processing with analysis of thermal and mechanical operations in space. Commercial firms provide cost inputs for ELM and planetary landing. Additional information is included in the

  11. Minimizing Launch Mass for ISRU Processes

    NASA Technical Reports Server (NTRS)

    England, C.; Hallinan, K. P.

    2004-01-01

    The University of Dayton and the Jet Propulsion Laboratory are developing a methodology for estimating the Earth launch mass (ELM) of processes for In-Situ Resource Utilization (ISRU) with a focus on lunar resource recovery. ISRU may be enabling for both an extended presence on the Moon, and for large sample return missions and for a human presence on Mars. To accomplish these exploration goals, the resources recovered by ISRU must offset the ELM for the recovery process. An appropriate figure of merit is the cost of the exploration mission, which is closely related to ELM. For a given production rate and resource concentration, the lowest ELM - and the best ISRU process - is achieved by minimizing capital equipment for both the ISRU process and energy production. ISRU processes incur Carnot limitations and second law losses (irreversibilities) that ultimately determine production rate, material utilization and energy efficiencies. Heat transfer, chemical reaction, and mechanical operations affect the ELM in ways that are best understood by examining the process's detailed energetics. Schemes for chemical and thermal processing that do not incorporate an understanding of second law losses will be incompletely understood. Our team is developing a methodology that will aid design and selection of ISRU processes by identifying the impact of thermodynamic losses on ELM. The methodology includes mechanical, thermal and chemical operations, and, when completed, will provide a procedure and rationale for optimizing their design and minimizing their cost. The technique for optimizing ISRU with respect to ELM draws from work of England and Funk that relates the cost of endothermic processes to their second law efficiencies. Our team joins their approach for recovering resources by chemical processing with analysis of thermal and mechanical operations in space. Commercial firms provide cost inputs for ELM and planetary landing. Additional information is included in the

  12. Plasma Assisted ISRU at Mars

    NASA Technical Reports Server (NTRS)

    Moses, Robert W.; Kuhl, Christopher A.; Templeton, Justin D.

    2005-01-01

    NASA's exploration goals for Mars and Beyond will require new power systems and in situ resource utilization (ISRU) technologies. Regenerative aerobraking may offer a revolutionary approach for in situ power generation and oxygen harvesting during these exploration missions. In theory, power and oxygen can be collected during aerobraking and stored for later use in orbit or on the planet. This technology would capture energy and oxygen from the plasma field that occurs naturally during hypersonic entry using well understood principles of magnetohydrodynamics and oxygen filtration. This innovative approach generates resources upon arrival at the operational site, and thus greatly differs from the traditional approach of taking everything you need with you from Earth. Fundamental analysis, computational fluid dynamics, and some testing of experimental hardware have established the basic feasibility of generating power during a Mars entry. Oxygen filtration at conditions consistent with spacecraft entry parameters at Mars has been studied to a lesser extent. Other uses of the MHD power are presented. This paper illustrates how some features of regenerative aerobraking may be applied to support human and robotic missions at Mars.

  13. Planetary Regolith Delivery Systems for ISRU

    NASA Technical Reports Server (NTRS)

    Mantovani, James G.; Townsend, Ivan I., III

    2012-01-01

    The challenges associated with collecting regolith on a planetary surface and delivering it to an in-situ resource utilization system differ significantly from similar activities conducted on Earth. Since system maintenance on a planetary body can be difficult or impossible to do, high reliability and service life are expected of a regolith delivery system. Mission costs impose upper limits on power and mass. The regolith delivery system must provide a leak-tight interface between the near-vacuum planetary surface and the pressurized ISRU system. Regolith delivery in amounts ranging from a few grams to tens of kilograms may be required. Finally, the spent regolith must be removed from the ISRU chamber and returned to the planetary environment via dust tolerant valves capable of operating and sealing over a large temperature range. This paper will describe pneumatic and auger regolith transfer systems that have already been field tested for ISRU, and discuss other systems that await future field testing.

  14. ISRU Technologies for Mars Life Support

    NASA Technical Reports Server (NTRS)

    Finn, John E.; Sridhar, K. R.

    2000-01-01

    The primary objectives of the Mars Exploration program are to collect data for planetary science in a quest to answer questions related to Origins, to search for evidence of extinct and extant life, and to expand the human presence in the solar system. The public and political engagement that is critical for support of a Mars exploration program is based on all of these objectives. In order to retain and to build public and political support, it is important for NASA to have an integrated Mars exploration plan, not separate robotic and human plans that exist in parallel or in sequence. The resolution stemming from the current architectural review and prioritization of payloads may be pivotal in determining whether NASA will have such a unified plan and retain public support. There are several potential scientific and technological links between the robotic-only missions that have been flown and planned to date, and the robotic + human missions that will come in the future. Taking advantage of and leveraging those links are central to the idea of a unified Mars exploration plan. One such link is in situ resource utilization (ISRU) as an enabling technology to provide consumables such as fuels, oxygen, sweep and utility gases from the Mars atmosphere. ISRU for propellant production and for generation of life support consumables is a key element of human exploration mission plans because of the tremendous savings that can be realized in terms of launch costs and reduction in overall risk to the mission. The Human Exploration and Development of Space (HEDS) Enterprise has supported ISRU technology development for several years, and is funding the MIP and PROMISE payloads that will serve as the first demonstrations of ISRU technology for Mars. In our discussion and presentation at the workshop, we will highlight how the PROMISE ISRU experiment that has been selected by HEDS for a future Mars flight opportunity can extend and enhance the science experiments on board.

  15. ISRU Technologies for Mars Life Support

    NASA Technical Reports Server (NTRS)

    Finn, John E.; Sridhar, K. R.

    2000-01-01

    The primary objectives of the Mars Exploration program are to collect data for planetary science in a quest to answer questions related to Origins, to search for evidence of extinct and extant life, and to expand the human presence in the solar system. The public and political engagement that is critical for support of a Mars exploration program is based on all of these objectives. In order to retain and to build public and political support, it is important for NASA to have an integrated Mars exploration plan, not separate robotic and human plans that exist in parallel or in sequence. The resolution stemming from the current architectural review and prioritization of payloads may be pivotal in determining whether NASA will have such a unified plan and retain public support. There are several potential scientific and technological links between the robotic-only missions that have been flown and planned to date, and the robotic + human missions that will come in the future. Taking advantage of and leveraging those links are central to the idea of a unified Mars exploration plan. One such link is in situ resource utilization (ISRU) as an enabling technology to provide consumables such as fuels, oxygen, sweep and utility gases from the Mars atmosphere. ISRU for propellant production and for generation of life support consumables is a key element of human exploration mission plans because of the tremendous savings that can be realized in terms of launch costs and reduction in overall risk to the mission. The Human Exploration and Development of Space (HEDS) Enterprise has supported ISRU technology development for several years, and is funding the MIP and PROMISE payloads that will serve as the first demonstrations of ISRU technology for Mars. In our discussion and presentation at the workshop, we will highlight how the PROMISE ISRU experiment that has been selected by HEDS for a future Mars flight opportunity can extend and enhance the science experiments on board.

  16. In-Situ Resource Utilization (ISRU) Development Program

    NASA Technical Reports Server (NTRS)

    Sanders, Jerry

    1998-01-01

    The question "Why In-Situ Resource Utilization (ISRU)?" is addressed in this presentation. The reasons given concentrate on Cost reduction, Mass reduction, Risk reduction, the expansion of human exploration and presence and the enabling of industrial exploitation. A review of the Martian and Lunar resources available for ISRU is presented. Other ISRU concepts (i.e., In-Situ Consumable production (ISCP) and In-Situ Propellant Production (ISPP)) are introduced and further explained. The objectives of a Mars ISRU System Technology (MIST) include (1) the characterization of technology and subsystem performance for mission modeling and technology funding planning, (2) reduce risk and concerns arising from sample return and human missions utilizing ISRU, and (3) demonstrate the environmental suitability of ISRU components/processes and systems. A proof of concept demonstration schedule and a facility overview for MIST is presented.

  17. Oxygen production System Models for Lunar ISRU

    NASA Technical Reports Server (NTRS)

    Santiago-Maldonado, Edgardo

    2007-01-01

    In-Situ Resource Utilization (ISRU) seeks to make human space exploration feasible; by using available resources from a planet or the moon to produce consumables, parts, and structures that otherwise would be brought from Earth. Producing these in situ reduces the mass of such that must be launched and doing so allows more payload mass' for each mission. The production of oxygen from lunar regolith, for life support and propellant, is one of the tasks being studied under ISRU. NASA is currently funding three processes that have shown technical merit for the production of oxygen from regolith: Molten Salt Electrolysis, Hydrogen Reduction of Ilmenite, and Carbothermal Reduction. The ISRU program is currently developing system models of, the , abovementioned processes to: (1) help NASA in the evaluation process to select the most cost-effective and efficient process for further prototype development, (2) identify key parameters, (3) optimize the oxygen production process, (4) provide estimates on energy and power requirements, mass and volume.of the system, oxygen production rate, mass of regolith required, mass of consumables, and other important parameters, and (5) integrate into the overall end-to-end ISRU system model, which could be integrated with mission architecture models. The oxygen production system model is divided into modules that represent unit operations (e.g., reactor, water electrolyzer, heat exchanger). Each module is modeled theoretically using Excel and Visual Basic for Applications (VBA), and will be validated using experimental data from on-going laboratory work. This modularity (plug-n-play) feature of each unit operation allows the use of the same model on different oxygen production systems simulations resulting in comparable results. In this presentation, preliminary results for mass, power, volume will be presented along with brief description of the oxygen production system model.

  18. A Nuclear Powered ISRU Mission to Mars

    NASA Astrophysics Data System (ADS)

    Finzi, Elvina; Davighi, Andrea; Finzi, Amalia

    2006-01-01

    Space exploration has always been drastically constrained by the masses that can be launched into orbit; Hence affordable planning and execution of prolonged manned space missions depend upon the utilization of local. Successful in-situ resources utilization (ISRU) is a key element to allow the human presence on Mars or the Moon. In fact a Mars ISRU mission is planned in the Aurora Program, the European program for the exploration of the solar system. Orpheus mission is a technological demonstrator whose purpose is to show the advantages of an In Situ Propellant Production (ISPP). Main task of this work is to demonstrate the feasibility of a nuclear ISPP plant. The mission designed has been sized to launch back form Mars an eventual manned module. The ISPP mission requires two different: the ISPP power plant module and the nuclear reactor module. Both modules reach the escape orbit thanks to the launcher upper stage, after a 200 days cruising phase the Martian atmosphere is reached thanks to small DV propelled manoeuvres, aerobreaking and soft landing. During its operational life the ISPP plant produces. The propellant is produced in one synodic year. 35000 kg of Ethylene are produced at the Martian equator. The resulting systems appear feasible and of a size comparable to other ISRU mission designs. This mission seems challenging not only for the ISPP technology to be demonstrated, but also for the space nuclear reactor considered; Though this seems the only way to allow a permanent human presence on Mars surface.

  19. A Nuclear Powered ISRU Mission to Mars

    SciTech Connect

    Finzi, Elvina; Davighi, Andrea; Finzi, Amalia

    2006-01-20

    Space exploration has always been drastically constrained by the masses that can be launched into orbit; Hence affordable planning and execution of prolonged manned space missions depend upon the utilization of local. Successful in-situ resources utilization (ISRU) is a key element to allow the human presence on Mars or the Moon. In fact a Mars ISRU mission is planned in the Aurora Program, the European program for the exploration of the solar system. Orpheus mission is a technological demonstrator whose purpose is to show the advantages of an In Situ Propellant Production (ISPP). Main task of this work is to demonstrate the feasibility of a nuclear ISPP plant. The mission designed has been sized to launch back form Mars an eventual manned module. The ISPP mission requires two different: the ISPP power plant module and the nuclear reactor module. Both modules reach the escape orbit thanks to the launcher upper stage, after a 200 days cruising phase the Martian atmosphere is reached thanks to small DV propelled manoeuvres, aerobreaking and soft landing. During its operational life the ISPP plant produces. The propellant is produced in one synodic year. 35000 kg of Ethylene are produced at the Martian equator. The resulting systems appear feasible and of a size comparable to other ISRU mission designs. This mission seems challenging not only for the ISPP technology to be demonstrated, but also for the space nuclear reactor considered; Though this seems the only way to allow a permanent human presence on Mars surface.

  20. Separation of Carbon Monoxide and Carbon Dioxide for Mars ISRU

    NASA Technical Reports Server (NTRS)

    Walton, Krista S.; LeVan, M. Douglas

    2004-01-01

    The atmosphere of Mars has many resources that can be processed to produce things such as oxygen, fuel, buffer gas, and water for support of human exploration missions. Successful manipulation of these resources is crucial for safe, cost-effective, and self-sufficient long-term human exploration of Mars. In our research, we are developing enabling technologies that require fundamental knowledge of adsorptive gas storage and separation processes. In particular, we are designing and constructing an innovative, low mass, low power separation device to recover carbon dioxide and carbon monoxide for Mars ISRU (in-situ resource utilization). The technology has broad implications for gas storage and separations for gas-solid systems that are ideally suited for reduced gravitational environments. This paper describes our separation process design and experimental procedures and reports results for the separation of CO2 and CO by a four-step adsorption cycle.

  1. ISRU Propellant Selection for Space Exploration Vehicles

    NASA Technical Reports Server (NTRS)

    Chen, Timothy T.

    2013-01-01

    Chemical propulsion remains the only viable solution as technically matured technology for the near term human space transportation to Lunar and Mars. Current mode of space travel requires us to "take everything we will need", including propellant for the return trip. Forcing the mission designers to carry propellant for the return trip limits payload mass available for mission operations and results in a large and costly (and often unaffordable) design. Producing propellant via In-Situ Resource Utilization (ISRU) will enable missions with chemical propulsion by the "refueling" of return-trip propellant. It will reduce vehicle propellant mass carrying requirement by over 50%. This mass reduction can translates into increased payload to enhance greater mission capability, reduces vehicle size, weight and cost. It will also reduce size of launch vehicle fairing size as well as number of launches for a given space mission and enables exploration missions with existing chemical propulsion. Mars remains the ultimate destination for Human Space Exploration within the Solar System. The Mars atmospheric consist of 95% carbon dioxide (CO2) and the presence of Ice (water) was detected on Mars surfaces. This presents a basic chemical building block for the ISRU propellant manufacturing. However, the rationale for the right propellant to produce via ISRU appears to be limited to the perception of "what we can produce" as oppose to "what is the right propellant". Methane (CH4) is often quoted as a logical choice for Mars ISRU propellant, however; it is believed that there are better alternatives available that can result in a better space transportation architecture. A system analysis is needed to determine on what is the right propellant choice for the exploration vehicle. This paper examines the propellant selection for production via ISRU method on Mars surfaces. It will examine propellant trades for the exploration vehicle with resulting impact on vehicle performance, size

  2. Mars ISRU for Production of Mission Critical Consumables - Options, Recent Studies, and Current State of the Art

    NASA Technical Reports Server (NTRS)

    Sanders, G. B.; Paz, A.; Oryshchyn, L.; Araghi, K.; Muscatello, A.; Linne, D.; Kleinhenz, J.; Peters, T.

    2015-01-01

    with Mars ISRU systems further substantiated the preliminary results from the Mars DRA 5.0 study. This paper will provide an overview of Mars ISRU consumable production options, the analyses, results, and conclusions from the Mars DRA 5.0 (2007), Mars Collaborative (2013), and Mars ISRU Payload for the Supersonic Retro Propulsion (2014) mission studies, and the current state-of-the-art of Mars ISRU technologies and systems. The paper will also briefly discuss the mission architectural implications associated with Mars resource and ISRU processing options.

  3. Biological Implications of Artificial Illumination.

    ERIC Educational Resources Information Center

    Wurtman, Richard J.

    1968-01-01

    Environmental lighting exerts profound biologic effects on humans and other mammals, in addition to providing the visual stimulus. Light acts on the skin to stimulate the synthesis of Vitamin D. It also acts, through the eyes, to control several glands and many metabolic processes. Light, or its absence, "induces" certain biologic functions. Light…

  4. Biological Implications of Artificial Illumination.

    ERIC Educational Resources Information Center

    Wurtman, Richard J.

    1968-01-01

    Environmental lighting exerts profound biologic effects on humans and other mammals, in addition to providing the visual stimulus. Light acts on the skin to stimulate the synthesis of Vitamin D. It also acts, through the eyes, to control several glands and many metabolic processes. Light, or its absence, "induces" certain biologic functions. Light…

  5. Biological Implications of Gene-Environment Interaction

    ERIC Educational Resources Information Center

    Rutter, Michael

    2008-01-01

    Gene-environment interaction (G x E) has been treated as both a statistical phenomenon and a biological reality. It is argued that, although there are important statistical issues that need to be considered, the focus has to be on the biological implications of G x E. Four reports of G x E deriving from the Dunedin longitudinal study are used as…

  6. Biological Implications of Gene-Environment Interaction

    ERIC Educational Resources Information Center

    Rutter, Michael

    2008-01-01

    Gene-environment interaction (G x E) has been treated as both a statistical phenomenon and a biological reality. It is argued that, although there are important statistical issues that need to be considered, the focus has to be on the biological implications of G x E. Four reports of G x E deriving from the Dunedin longitudinal study are used as…

  7. Microgravity Materials Research and Code U ISRU

    NASA Technical Reports Server (NTRS)

    Curreri, Peter A.; Sibille, Laurent

    2004-01-01

    The NASA microgravity research program, simply put, has the goal of doing science (which is essentially finding out something previously unknown about nature) utilizing the unique long-term microgravity environment in Earth orbit. Since 1997 Code U has in addition funded scientific basic research that enables safe and economical capabilities to enable humans to live, work and do science beyond Earth orbit. This research has been integrated with the larger NASA missions (Code M and S). These new exploration research focus areas include Radiation Shielding Materials, Macromolecular Research on Bone and Muscle Loss, In Space Fabrication and Repair, and Low Gravity ISRU. The latter two focus on enabling materials processing in space for use in space. The goal of this program is to provide scientific and technical research resulting in proof-of-concept experiments feeding into the larger NASA program to provide humans in space with an energy rich, resource rich, self sustaining infrastructure at the earliest possible time and with minimum risk, launch mass and program cost. President Bush's Exploration Vision (1/14/04) gives a new urgency for the development of ISRU concepts into the exploration architecture. This will require an accelerated One NASA approach utilizing NASA's partners in academia, and industry.

  8. Molecular biology of lung cancer: clinical implications.

    PubMed

    Larsen, Jill E; Minna, John D

    2011-12-01

    Lung cancer is a heterogeneous disease clinically, biologically, histologically, and molecularly. Understanding the molecular causes of this heterogeneity, which might reflect changes occurring in different classes of epithelial cells or different molecular changes occurring in the same target lung epithelial cells, is the focus of current research. Identifying the genes and pathways involved, determining how they relate to the biological behavior of lung cancer, and their utility as diagnostic and therapeutic targets are important basic and translational research issues. This article reviews current information on the key molecular steps in lung cancer pathogenesis, their timing, and clinical implications. Published by Elsevier Inc.

  9. Vacuum Pyrolysis and Related ISRU Techniques

    NASA Technical Reports Server (NTRS)

    Cardiff, Eric H.; Pomeroy, Brian R.; Banks, Ian S.; Benz, Alexis

    2007-01-01

    A number of ISRU-related techniques have been developed at NASA Goddard Space Flight Center. The focus of the team has been on development of the vacuum pyrolysis technique for the production of oxygen from the lunar regolith. However, a number of related techniques have also been developed, including solar concentration, solar heating of regolith, resistive heating of regolith, sintering, regolith boiling, process modeling, parts manufacturing, and instrumentation development. An initial prototype system was developed to vaporize regolith simulants using a approx. l square meter Fresnel lens. This system was successfully used to vaporize quantities of approx. lg, and both mass spectroscopy of the gasses produced and Scanning Electron Microscopy (SEM) of the slag were done to show that oxygen was produced. Subsequent tests have demonstrated the use of a larger system With a 3.8m diameter reflective mirror to vaporize the regolith. These results and modeling of the vacuum pyrolysis reaction have indicated that the vaporization of the oxides in the regolith will occur at lower temperature for stronger vacuums. The chemical modeling was validated by testing of a resistive heating system that vaporized quantities of approx. 10g of MLS-1A. This system was also used to demonstrate the sintering of regolith simulants at reduced temperatures in high vacuum. This reduction in the required temperature prompted the development of a small-scale resistive heating system for application as a scientific instrument as well as a proof-of principle experiment for oxygen production.

  10. Opportunities for ISRU Applications in the Mars Reference Mission

    NASA Astrophysics Data System (ADS)

    Duke, Michael B.

    1998-01-01

    The use of in-situ resources in the Mars Reference Mission is discussed in this presentation. The objectives of the presentation are to consider whether In Situ Resource Use (ISRU), other than propellants and life support consumables can be useful, and to outline the type of analysis that has to be performed to evaluate the ISRU use, and to suggest some areas for investigation. The presentation also discusses ways to reduce risk, and cost. Possible strategies are posed, including use of robotic systems. The use of robotic systems could reduce total mass required for the mission by producing required material over a long period of time. Several examples are discussed. (1) In the presentation the possible use of ISRU in making concrete for structures is discussed. Using robots to produce, mix, form, and cure the concrete, ISRU concrete may be able to compete with earth supply. (2) The use of robots to grade roads is also discussed. The use of ISRU is more complex than bringing things from Earth.

  11. ISRU in the Context of Future European Human Mars Exploration

    NASA Astrophysics Data System (ADS)

    Baker, A. M.; Tomatis, C.

    2002-01-01

    ISRU or In-Situ Resource Utilisation is the use of Martian resources to manufacture, typically, life support consumables (e.g. water, oxygen, breathing buffer gases), and propellant for a return journey to Earth. European studies have shown that some 4kg of reaction mass must be launched to LEO to send 1kg payload to Mars orbit, with landing on the Mars surface reducing payload mass still further. This results in very high transportation costs to Mars, and still higher costs for returning payloads to Earth. There is therefore a major incentive to reduce payload mass for any form of Mars return mission (human or otherwise) by generating consumables on the surface. ESA through its GSTP programme has been investigating the system level design of a number of mission elements as potential European contributions to an international human Mars exploration mission intended for the 2020-2030 timeframe. One of these is an ISRU plant, a small chemical factory to convert feedstock brought from Earth (hydrogen), and Martian atmospheric gases (CO2 and trace quantities of nitrogen and argon) into methane and oxygen propellant for Earth return and life support consumables, in advance of the arrival of astronauts. ISRU technology has been the subject of much investigation around the world, but little detailed research or system level studies have been reported in Europe. Furthermore, the potential applicability of European expertise, technology and sub- system studies to Martian ISRU is not well quantified. Study work covered in this paper has compared existing designs (e.g. NASA's Design Reference Mission, DLR and Mars Society studies) with the latest ESA derived requirements for human Mars exploration, and has generated a system level ISRU design. This paper will review and quantify the baseline chemical reactions essential for ISRU, including CO2 collection and purification, Sabatier reduction of CO2 with hydrogen to methane and water, and electrolysis of water in the context of

  12. Biological implications of thymectomy for myasthenia gravis.

    PubMed

    Okumura, Meinoshin; Inoue, Masayoshi; Kadota, Yoshihisa; Hayashi, Akio; Tokunaga, Toshiteru; Kusu, Takashi; Sawabata, Noriyoshi; Shiono, Hiroyuki

    2010-01-01

    Myasthenia gravis (MG) is an autoimmune disease mediated by autoantibodies to the striated muscle tissue. It is often treated by thymectomy. We review recent studies to investigate the biological implications of thymectomy. In anti-acetylcholine receptor antibody (anti-AchR Ab)-positive patients without a thymoma, abnormal germinal center formation in the thymus seems to play an essential role in the pathogenesis of MG. Specific differentiation of B cells producing anti-AchR Ab takes place uniquely in the thymus, and thymectomy is thought to assist in terminating the provision of high-affinity anti-AchR antibody-producing cells to peripheral organs. Thymectomy is not indicated for anti-AchR Ab-negative MG patients who are antimuscle specific kinase antibody (anti-MuSK Ab)-positive, although some anti-MuSK Ab-negative patients may benefit from the procedure. A thymoma can be considered as an acquired thymus with insufficient function of negative selection. The resection of a thymoma is thought to terminate the production of self-reactive T cells. Thus, the biological implications of thymectomy for MG have been partially revealed. Nevertheless, additional studies are needed to elucidate the ontogeny of T cells that recognize AchR and the mechanism of the activation of anti-AchR antibodies producing B cells.

  13. In Situ Resource Utilization (ISRU 3) Technical Interchange Meeting: Abstracts

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This volume contains abstracts that have been accepted for presentation at the In Situ Resource Utilization (ISRU III) Technical Interchange Meeting, February 11-12, 1999, hosted by the Lockheed Martin Astronautics Waterton Facility, Denver, Colorado. Administration and publication support for this meeting were provided by the staff of the Publications and Program Services Department at the Lunar and Planetary Institute.

  14. Martian Atmospheric Dust Mitigation for ISRU Intakes via Electrostatic Precipitation

    NASA Technical Reports Server (NTRS)

    Phillips, James R., III; Pollard, Jacob R. S.; Johansen, Michael R.; Mackey, Paul J.; Clements, J. Sid; Calle, Carlos I.

    2016-01-01

    The Mars 2020 and Mars Sample Return missions expected to fly to Mars within the next ten years will each include an In Situ Resource Utilization (ISRU) system. They convert carbon dioxide in the Martian atmosphere into consumable oxygen at 1% and 20% of the rate required by a full scale human exploration Mars mission, respectively. The ISRU systems will need to draw in the surrounding atmosphere at a rate of 110L/min and 550L/min, respectively, in order to meet their oxygen production goals. Over the duration of each respective mission, a total atmospheric dust mass of 4.86g and 243g will be drawn into each system, respectively. Ingestion of large quantities of dust may interfere with ISRU operations, so a dust mitigation device will be required. The atmospheric volume and dust mass flow rates above will be utilized to simulate Martian environmental conditions in a laboratory electrostatic precipitator being developed to provide active dust mitigation support for atmospheric ISRU systems such as these.

  15. In Situ Resource Utilization (ISRU) Technical Interchange Meeting

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This volume contains abstracts that have been accepted for presentation at the In Situ Resource Utilization (ISRU) Technical Interchange Meeting, February 4-5, 1997, at the Lunar and Planetary Institute, Houston, Texas. Abstracts are arranged in order of presentation at the meetings, with corresponding page numbers shown in the enclosed agenda. Logistics, administration, and publication support for this meeting were provided by the staff of the Publications and Program Services Department at the Lunar and Planetary Institute.

  16. In Situ Resource Utilization (ISRU II) Technical Interchange Meeting

    NASA Technical Reports Server (NTRS)

    Kaplan, David (Compiler); Saunders, Stephen R. (Compiler)

    1997-01-01

    This volume contains extended abstracts that have been accepted for presentation at the In Situ Resource Utilization (ISRU II) Technical Interchange Meeting, November 18-19, 1997, at the Lunar and Planetary Institute, Houston, Texas. Included are topics which include: Extraterrestrial resources, in situ propellant production, sampling of planetary surfaces, oxygen production, water vapor extraction from the Martian atmosphere, gas generation, cryogenic refrigeration, and propellant transport and storage.

  17. ISRU: Automated Water Extraction Ffrom Mars Surface Soils for Sample Return Missions

    NASA Astrophysics Data System (ADS)

    Willson, D.

    2012-06-01

    An ISRU option for Mars sample return vehicles is to employ a Sojourner/MER sized bucket excavation rover that mines and extracts water from the top 5 cm of surface soils and delivers it to an ISRU on the lander. The option is mass competitive.

  18. Discussion of thermal extraction chamber concepts for Lunar ISRU

    NASA Astrophysics Data System (ADS)

    Pfeiffer, Matthias; Hager, Philipp; Parzinger, Stephan; Dirlich, Thomas; Spinnler, Markus; Sattelmayer, Thomas; Walter, Ulrich

    The Exploration group of the Institute of Astronautics (LRT) of the Technische Universitüt a München focuses on long-term scenarios and sustainable human presence in space. One of the enabling technologies in this long-term perspective is in-situ resource utilization (ISRU). When dealing with the prospect of future manned missions to Moon and Mars the use of ISRU seems useful and intended. The activities presented in this paper focus on Lunar ISRU. This basically incorporates both the exploitation of Lunar oxygen from natural rock and the extraction of solar wind implanted particles (SWIP) from regolith dust. Presently the group at the LRT is examining possibilities for the extraction of SWIPs, which may provide several gaseous components (such as H2 and N2) valuable to a human presence on the Moon. As a major stepping stone in the near future a Lunar demonstrator/ verification experiment payload is being designed. This experiment, LUISE (LUnar ISru Experiment), will comprise a thermal process chamber for heating regolith dust (grain size below 500m), a solar thermal power supply, a sample distribution unit and a trace gas analysis. The first project stage includes the detailed design and analysis of the extraction chamber concepts and the thermal process involved in the removal of SWIP from Lunar Regolith dust. The technique of extracting Solar Wind volatiles from Regolith has been outlined by several sources. Heating the material to a threshold value seems to be the most reasonable approach. The present paper will give an overview over concepts for thermal extraction chambers to be used in the LUISE project and evaluate in detail the pros and cons of each concept. The special boundary conditions set by solar thermal heating of the chambers as well as the material properties of Regolith in a Lunar environment will be discussed. Both greatly influence the design of the extraction chamber. The performance of the chamber concepts is discussed with respect to the

  19. Calculation of Excavation Force for ISRU on Lunar Surface

    NASA Technical Reports Server (NTRS)

    Zeng, Xiangwu (David); Burnoski, Louis; Agui, Juan H.; Wilkinson, Allen

    2007-01-01

    Accurately predicting the excavation force that will be encountered by digging tools on the lunar surface is a crucial element of in-situ resource utilization (ISRU). Based on principles of soil mechanics, this paper develops an analytical model that is relatively simple to apply and uses soil parameters that can be determined by traditional soil strength tests. The influence of important parameters on the excavation force is investigated. The results are compared with that predicted by other available theories. Results of preliminary soil tests on lunar stimulant are also reported.

  20. ATHLETE as a Mobile ISRU and Regolith Construction Platform

    NASA Technical Reports Server (NTRS)

    Howe, A. Scott; Wilcox, Brian; Barmatz, Martin; Voecks, Gerald

    2016-01-01

    The All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) robotic mobility platform can provide precision positioning and mobility for site preparation and regolith construction needs. ATHLETE is a multi-use platform designed to use swap-out tools and implements that can be applied to any number of tasks that need precision limb manipulation or mobility. Major capabilities include off-loading habitats, transporting surface assets, robotically assembling outposts from multiple mission manifests, and supporting science and technology objectives. This paper describes conceptual approaches for supporting NASA regolith construction research, such as additive construction, modular brick and panel factory, and mobile ISRU platform.

  1. Opportunities for ISRU Applications in the Mars Reference Mission

    NASA Astrophysics Data System (ADS)

    Duke, Michael B.

    1998-01-01

    The NASA Mars Exploration Reference Mission envisions sending three crews of six astronauts to Mars, each for 500-day stays on the surface. In situ Resourse Unitlization (ISRU) has been baselined for the production of propellant for crews leaving the surface, as well as to create reservoirs of water and life-support consumables These applications improve performance (by reducing the mass of hardware and supplies that must be brought to Mars for the propulsion system) and reduce risk (by creating consumables as backups to stores brought from Earth). Similar applications of other types of ISRU-derived materials should be sought and selected if they similarly improve performance or reduce risk. Some possible concepts for consideration, based on a review of the components included in the Reference Mission, include (1) emplacement of a hardened landing pad; (2) construction of a roadway for transporting the nuclear power system to a safe distance from the habitat; (3) radiation shielding for inflatable structures; (4) tanks and plumbing for bioregenerative life-support system; (5) drilling rig; (6) additional access structures for equipment and personnel and unpressurized structures for vehicle storage; (7) utilitarian manufactured products (e.g., stools and benches) for habitat and laboratory; (8) thermal radiators; (9) photovoltaic devices and support structures; and ( 10) external structures for storage and preservation of Mars samples. These may be viewed principally as mission- enhancing concepts for the Reference Mission. Selection would require a clear rationale for performance improvement or risk reduction and a demonstration that the cost of developing and transporting the needed equipment would be recovered within the budget for the program. Additional work is also necessary to ascertain whether early applications of ISRU for these types of purposes could lead to the modification of later missions, allowing the replacement of infrastructure payloads currently

  2. Resource Prospector: A Lunar Volatiles Prospecting and ISRU Demonstration Mission

    NASA Technical Reports Server (NTRS)

    Colaprete, Anthony

    2015-01-01

    A variety of recent observations have indicated several possible reservoirs of water and other volatiles. These volatiles, and in particular water, have the potential to be a valuable or enabling resource for future exploration. NASA's Human Exploration and Operations Mission Directorate (HEOMD) Advanced Exploration Systems (AES) is supporting the development of Resource Prospector (RP) to explore the distribution and concentration of lunar volatiles prospecting and to demonstrate In-Situ Resource Utilization (ISRU). The mission includes a NASA developed rover and payload, and a lander will most likely be a contributed element by an international partner or the Lunar Cargo Transportation and Landing by Soft Touchdown (CATALYST) initiative. The RP payload is designed to: (1) locate near-subsurface volatiles, (2) excavate and analyze samples of the volatile-bearing regolith, and (3) demonstrate the form. extractability and usefulness of the materials. RP is being designed with thought given to its extensibility to resource prospecting and ISRU on other airless bodies and Mars. This presentation will describe the Resource Prospector mission, the payload and measurements, and concept of operations

  3. Field Scale Testing of RESOLVE at 2010 ISRU Analog Test

    NASA Technical Reports Server (NTRS)

    Captain, Janine E.; Quinn, J. W.; Moss, T. J.; Weis, K. H.

    2010-01-01

    When mankind returns to the moon, there will be one aspect of the architecture that will totally change how we explore the solar system. For the first time in space exploration, we will take the initial steps towards breaking our reliance on Earth-supplied consumables by extracting resources from planetary bodies. Our first efforts in this area, known as In Situ Resource Utilization (ISRU), will be directed at extracting some of the abundant oxygen found in the lunar regolith. But the "holy grail" of lunar ISRU will be finding an exploitable source of lunar hydrogen. If we can find a source of hydrogen that can be reasonably extracted from the regolith, it would provide a foundation for true independence from Earth consumables. With in-situ hydrogen and oxygen (and/or water) we can produce many of the major consumables needed to travel to and operate on a sustainable lunar outpost. We would have water to drink, oxygen to breath, and rocket propellants and fuel cell reagents to enable extended access and operations across the moon. NASA initiated development of an experiment package named RESOLVE (Regolith & Environment Science and Oxygen & Lunar Volatile Extraction) that could be flown to the rim or into a permanently shadowed crater to answer the questions surrounding elevated hydrogen at the lunar poles.

  4. The Biology of Trauma: Implications for Treatment

    ERIC Educational Resources Information Center

    Solomon, Eldra P.; Heide, Kathleen M.

    2005-01-01

    During the past 20 years, the development of brain imaging techniques and new biochemical approaches has led to increased understanding of the biological effects of psychological trauma. New hypotheses have been generated about brain development and the roots of antisocial behavior. We now understand that psychological trauma disrupts homeostasis…

  5. The Biology of Trauma: Implications for Treatment

    ERIC Educational Resources Information Center

    Solomon, Eldra P.; Heide, Kathleen M.

    2005-01-01

    During the past 20 years, the development of brain imaging techniques and new biochemical approaches has led to increased understanding of the biological effects of psychological trauma. New hypotheses have been generated about brain development and the roots of antisocial behavior. We now understand that psychological trauma disrupts homeostasis…

  6. The biology of trauma: implications for treatment.

    PubMed

    Solomon, Eldra P; Heide, Kathleen M

    2005-01-01

    During the past 20 years, the development of brain imaging techniques and new biochemical approaches has led to increased understanding of the biological effects of psychological trauma. New hypotheses have been generated about brain development and the roots of antisocial behavior. We now understand that psychological trauma disrupts homeostasis and can cause both short and long-term effects on many organs and systems of the body. Our expanding knowledge of the effects of trauma on the body has inspired new approaches to treating trauma survivors. Biologically informed therapy addresses the physiological effects of trauma, as well as cognitive distortions and maladaptive behaviors. The authors suggest that the most effective therapeutic innovation during the past 20 years for treating trauma survivors has been Eye Movement Desensitization and Reprocessing (EMDR), a therapeutic approach that focuses on resolving trauma using a combination of top-down (cognitive) and bottom-up (affect/body) processing.

  7. Arenavirus genetic diversity and its biological implications.

    PubMed

    Emonet, Sebastien F; de la Torre, Juan C; Domingo, Esteban; Sevilla, Noemí

    2009-07-01

    The Arenaviridae family currently comprises 22 viral species, each of them associated with a rodent species. This viral family is important both as tractable experimental model systems to study acute and persistent infections and as clinically important human pathogens. Arenaviruses are enveloped viruses with a bi-segmented negative-strand RNA genome. The interaction with the cellular receptor and subsequent entry into the host cell differs between Old World and New World arenavirus that use alpha-dystoglycan or human transferring receptor 1, respectively, as main receptors. The recent development of reverse genetic systems for several arenaviruses has facilitated progress in understanding the molecular biology and cell biology of this viral family, as well as opening new approaches for the development of novel strategies to combat human pathogenic arenaviruses. On the other hand, increased availability of genetic data has allowed more detailed studies on the phylogeny and evolution of arenaviruses. As with other riboviruses, arenaviruses exist as viral quasispecies, which allow virus adaptation to rapidly changing environments. The large number of different arenavirus host reservoirs and great genetic diversity among virus species provide the bases for the emergence of new arenaviruses potentially pathogenic for humans.

  8. [The ethical implications of conserving biological samples].

    PubMed

    Tazzite, A; Roky, R; Avard, D

    2009-09-01

    The conservation and use of biological samples become more and more frequent all around the world. Biobanks of human body substances (blood, urine, DNA, tissues, cells, etc.), and personal data associated with them are created. They have a double character as they are collections of both human biological samples and personal data. In some cases, the gametes, reproductive tissues, embryos, foetal tissue after abortion or even specimens of dead donors are collected and conserved. Although biobanks raise hopes in both the development of new therapies, new drugs and their integration into clinical medicine, they also point to concerns related to ethical questions such as: the principles of information, the consent of the persons concerned, the confidentiality about the personal data, and in some cases discrimination and stigmatisation. Other ethical aspects could raise gradually as research advance. Research being carried out on human sample requires informed free consent from the person who should be able to consent. The donor must be sufficiently informed about the process of research, the purpose, benefits and the risks involved in participating in this research. In the case of persons unable to give consent such minors or persons with mental disabilities, special measures are undertaken. Once the consent was given, the right of withdrawal has been consistently supported by the various declarations and regulations, but some oppose this right for a number of reasons particularly in the case of research on the samples without risk of physical exposure. In this case the notion of human body integrity is different than in research involving therapeutic or clinical intervention. In the case of withdrawal of consent, the samples should be destroyed, but the anonymous results arising from them and their analysis are not affected. What is the case for future uses? Should the researcher obtain again the consent from the donor for a secondary use of the samples? This is a

  9. ISRU Production of Life Support Consumables for a Lunar Base

    NASA Technical Reports Server (NTRS)

    Cooper, Bonnie L.; Simon, Tom

    2007-01-01

    Similar to finding a home on Earth, location is important when selecting where to set up an exploration outpost. Essential considerations for comparing potential lunar outpost locations include: (1) areas nearby that would be useful for In-Situ Resource Utilization (ISRU) oxygen extraction from regolith for crew breathing oxygen as well as other potential uses; (2) proximity to a suitable landing site; (3) availability of sunlight; (4) capability for line-of-sight communications with Earth; (5) proximity to permanently-shadowed areas for potential in-situ water ice; and (6) scientific interest. The Mons Malapert1 (Malapert Mountain) area (85.5degS, 0degE) has been compared to these criteria, and appears to be a suitable location for a lunar outpost.

  10. Local Citation Analysis of Graduate Biology Theses: Collection Development Implications

    ERIC Educational Resources Information Center

    Miller, Laura Newton

    2011-01-01

    This paper will focus on the citation analysis of graduate masters theses from Carleton University's Biology Department with implications for library collection management decisions. Twenty-five masters theses were studied to determine citation types and percentages, ranking of journals by frequency of citation and by number of authors citing, and…

  11. Environment, Biology, and Culture: Implications for Adolescent Development.

    ERIC Educational Resources Information Center

    Zahn-Waxler, Carolyn

    1996-01-01

    Introduces this special theme issue examining the roles of socialization, biology, and culture as they affect adaptive and maladaptive developmental outcomes. Problems of adolescence addressed include antisocial behavior, depressive symptoms, substance abuse, low achievement, and eating problems. Considers factors implicated in successful…

  12. Local Citation Analysis of Graduate Biology Theses: Collection Development Implications

    ERIC Educational Resources Information Center

    Miller, Laura Newton

    2011-01-01

    This paper will focus on the citation analysis of graduate masters theses from Carleton University's Biology Department with implications for library collection management decisions. Twenty-five masters theses were studied to determine citation types and percentages, ranking of journals by frequency of citation and by number of authors citing, and…

  13. Thermodynamic model of Mars Oxygen ISRU Experiment (MOXIE)

    NASA Astrophysics Data System (ADS)

    Meyen, Forrest E.; Hecht, Michael H.; Hoffman, Jeffrey A.

    2016-12-01

    As humankind expands its footprint in the solar system, it is increasingly important to make use of the resources already in our solar system to make these missions economically feasible and sustainable. In-Situ Resource Utilization (ISRU), the science of using resources at a destination to support exploration missions, unlocks potential destinations by significantly reducing the amount of resources that need to be launched from Earth. Carbon dioxide is an example of an in-situ resource that comprises 96% of the Martian atmosphere and can be used as a source of oxygen for propellant and life support systems. The Mars Oxygen ISRU Experiment (MOXIE) is a payload being developed for NASA's upcoming Mars 2020 rover. MOXIE will produce oxygen from the Martian atmosphere using solid oxide electrolysis (SOXE). MOXIE is on the order of magnitude of a 1% scale model of an oxygen processing plant that might enable a human expedition to Mars in the 2030s through the production of the oxygen needed for the propellant of a Mars ascent vehicle. MOXIE is essentially an energy conversion system that draws energy from the Mars 2020 rover's radioisotope thermoelectric generator and ultimately converts it to stored energy in oxygen and carbon monoxide molecules. A thermodynamic model of this novel system is used to understand this process in order to derive operating parameters for the experiment. This paper specifically describes the model of the SOXE component. Assumptions and idealizations are addressed, including 1D and 2D simplifications. Operating points are discussed as well as impacts of flow rates and production.

  14. ISRU System Model Tool: From Excavation to Oxygen Production

    NASA Technical Reports Server (NTRS)

    Santiago-Maldonado, Edgardo; Linne, Diane L.

    2007-01-01

    In the late 80's, conceptual designs for an in situ oxygen production plant were documented in a study by Eagle Engineering [1]. In the "Summary of Findings" of this study, it is clearly pointed out that: "reported process mass and power estimates lack a consistent basis to allow comparison." The study goes on to say: "A study to produce a set of process mass, power, and volume requirements on a consistent basis is recommended." Today, approximately twenty years later, as humans plan to return to the moon and venture beyond, the need for flexible up-to-date models of the oxygen extraction production process has become even more clear. Multiple processes for the production of oxygen from lunar regolith are being investigated by NASA, academia, and industry. Three processes that have shown technical merit are molten regolith electrolysis, hydrogen reduction, and carbothermal reduction. These processes have been selected by NASA as the basis for the development of the ISRU System Model Tool (ISMT). In working to develop up-to-date system models for these processes NASA hopes to accomplish the following: (1) help in the evaluation process to select the most cost-effective and efficient process for further prototype development, (2) identify key parameters, (3) optimize the excavation and oxygen production processes, and (4) provide estimates on energy and power requirements, mass and volume of the system, oxygen production rate, mass of regolith required, mass of consumables, and other important parameters. Also, as confidence and high fidelity is achieved with each component's model, new techniques and processes can be introduced and analyzed at a fraction of the cost of traditional hardware development and test approaches. A first generation ISRU System Model Tool has been used to provide inputs to the Lunar Architecture Team studies.

  15. The Mars Oxygen ISRU Experiment (MOXIE) on the Mars 2020 Rover

    NASA Astrophysics Data System (ADS)

    Hecht, M. H.; Hoffman, J. A.; Moxie Team

    2016-10-01

    The Mars Oxygen ISRU Experiment (MOXIE) is a technology experiment on the Mars 2020 Rover mission that will demonstrate the production of oxygen from atmospheric carbon dioxide as a precursor to a future human mission.

  16. Topological implications of negative curvature for biological and social networks

    NASA Astrophysics Data System (ADS)

    Albert, Réka; DasGupta, Bhaskar; Mobasheri, Nasim

    2014-03-01

    Network measures that reflect the most salient properties of complex large-scale networks are in high demand in the network research community. In this paper we adapt a combinatorial measure of negative curvature (also called hyperbolicity) to parametrized finite networks, and show that a variety of biological and social networks are hyperbolic. This hyperbolicity property has strong implications on the higher-order connectivity and other topological properties of these networks. Specifically, we derive and prove bounds on the distance among shortest or approximately shortest paths in hyperbolic networks. We describe two implications of these bounds to crosstalk in biological networks, and to the existence of central, influential neighborhoods in both biological and social networks.

  17. Results from the NASA Capability Roadmap Team for In-Situ Resource Utilization (ISRU)

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.; Romig, Kris A.; Larson, William E.; Johnson, Robert; Rapp, Don; Johnson, Ken R.; Sacksteder, Kurt; Linne, Diane; Curreri, Peter; Duke, Michael; hide

    2005-01-01

    On January 14, 2004, the President of the United States unveiled a new vision for robotic and human exploration of space entitled, "A Renewed Spirit of Discovery". As stated by the President in the Vision for Space Exploration (VSE), NASA must "... implement a sustained and affordable human and robotic program to explore the solar system and beyond " and ".. .develop new technologies and harness the moon's abundant resources to allow manned exploration of more challenging environments." A key to fulfilling the goal of sustained and affordable human and robotic exploration will be the ability to use resources that are available at the site of exploration to "live off the land" instead of bringing everything from Earth, known as In-Situ Resource Utilization (ISRU). ISRU can significantly reduce the mass, cost, and risk of exploration through capabilities such as: mission consumable production (propellants, fuel cell reagents, life support consumables, and feedstock for manufacturing & construction); surface construction (radiation shields, landing pads, walls, habitats, etc.); manufacturing and repair with in-situ resources (spare parts, wires, trusses, integrated systems etc.); and space utilities and power from space resources. On January 27th, 2004 the President's Commission on Implementation of U.S. Space Exploration Policy (Aldridge Committee) was created and its final report was released in June 2004. One of the report's recommendations was to establish special project teams to evaluate enabling technologies, of which "Planetary in situ resource utilization" was one of them. Based on the VSE and the commission's final report, NASA established fifteen Capability Roadmap teams, of which ISRU was one of the teams established. From Oct. 2004 to May 2005 the ISRU Capability Roadmap team examined the capabilities, benefits, architecture and mission implementation strategy, critical decisions, current state-of-the-art (SOA), challenges, technology gaps, and risks of

  18. Arenavirus Quasispecies and Their Biological Implications.

    PubMed

    Grande-Pérez, Ana; Martin, Veronica; Moreno, Hector; de la Torre, Juan C

    2016-01-01

    arenavirus adaptability and pathogenesis. Here, we will review several aspects of the molecular biology of arenaviruses, phylogeny and evolution, and quasispecies dynamics of arenavirus populations for a better understanding of arenavirus pathogenesis, as well as for the development of novel antiviral strategies to combat arenavirus infections.

  19. NASA In-Situ Resource Utilization (ISRU) Technology and Development Project Overview

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.; Lason, William E.; Sacksteder, Kurt R.; Mclemore, Carole; Johnson, Kenneth

    2008-01-01

    Since the Vision for Space Exploration (VSE) was released in 2004, NASA, in conjunction with international space agencies, industry, and academia, has continued to define and refine plans for sustained and affordable robotic and human exploration of the Moon and beyond. With the goal of establishing a lunar Outpost on the Moon to extend human presence, pursue scientific activities, use the Moon to prepare for future human missions to Mars, and expand Earth s economic sphere, a change in how space exploration is performed is required. One area that opens up the possibility for the first time of breaking our reliance on Earth supplied consumables and learn to live off the land is In-Situ Resource Utilization (ISRU). ISRU, which involves the extraction and processing of space resources into useful products, can have a substantial impact on mission and architecture concepts. In particular, the ability to make propellants, life support consumables, and fuel cell reagents can significantly reduce the cost, mass, and risk of sustained human activities beyond Earth. However, ISRU is an unproven capability for human lunar exploration and can not be put in the critical path of lunar Outpost success until it has been proven. Therefore, ISRU development and deployment needs to take incremental steps toward the desired end state. To ensure ISRU capabilities are available for pre-Outpost and Outpost deployment by 2020, and mission and architecture planners are confident that ISRU can meet initial and long term mission requirements, the ISRU Project is developing technologies and systems in three critical areas: (1) Regolith Excavation, Handling and Material Transportation; (2) Oxygen Extraction from Regolith; and (3) Volatile Extraction and Resource Prospecting, and in four development stages: (I) Demonstrate feasibility; (II) Evolve system w/ improved technologies; (III) Develop one or more systems to TRL 6 before start of flight development; and (IV) Flight development for

  20. New Developments in Mast Cell Biology: Clinical Implications.

    PubMed

    Arthur, Greer; Bradding, Peter

    2016-09-01

    Mast cells (MCs) are present in connective tissue and at mucosal surfaces in all classes of vertebrates. In health, they contribute to tissue homeostasis, host defense, and tissue repair via multiple receptors regulating the release of a vast stockpile of proinflammatory mediators, proteases, and cytokines. However, these potentially protective cells are a double-edged sword. When there is a repeated or long-term stimulus, MC activation leads to tissue damage and dysfunction. Accordingly, MCs are implicated in the pathophysiologic aspects of numerous diseases covering all organs. Understanding the biology of MCs, their heterogeneity, mechanisms of activation, and signaling cascades may lead to the development of novel therapies for many diseases for which current treatments are lacking or are of poor efficacy. This review will focus on updates and developments in MC biology and their clinical implications, with a particular focus on their role in respiratory diseases.

  1. In Situ Resource Utilization (ISRU) Experiments for Mars Exploration

    NASA Technical Reports Server (NTRS)

    Marone, Matt

    2005-01-01

    In situ resource utilization can best be described as living off the land. In our case the land is the planet Mars. ISRU is based on the idea that some fraction of the consumables, life support and propellant materials do not have to be flown from earth. Rather, they can be manufactured or extracted from resources already present on Mars. The primary resources on Mars are the atmosphere, polar caps and regolith. The atmosphere of Mars is mostly carbon dioxide as shown in the table below. The proportion of oxygen on the other hand is quite small. Still, there is quite a bit of oxygen in the Martian atmosphere, but it is unfortunately tied up with carbon. Thus, one of the goals of ISRU is the separation of breathable oxygen from the carbon dioxide. Several means of separation have been proposed. We have begun experiments on another approach for production of oxygen with carbon monoxide as a useful by product. Our work on a CO2 separator is described later in this report. Regolith melting is another means of obtaining materials. Two materials of interest are iron and silicon. Iron oxide is plentiful on Mars and is of obvious importance for structural components. Silicon is the foundation of solid state devices. Power generation on Mars may be accomplished using silicon solar cells. There is discussion of the feasibility of in situ production of solar cells. This would require a means of extracting silicon from the regolith. We have conducted several experiments concerning melting and glassification of the Mars soil simulant. Other summer faculty fellows have tried various means of processing the stimulant material. These include furnace melting, microwave melting and laser ablation. We have conducted several furnace melting experiments in both air and carbon dioxide environments. We have also carried out experiments to test spark melting in a carbon dioxide atmosphere. These experiments suggest the possibility of using arc melting in a reducing atmosphere. It is

  2. ISRU Development Strategy and Recent Activities to Support Near and Far Term Missions

    NASA Astrophysics Data System (ADS)

    Baird, Russell S.; Sanders, Gerald B.; Simon, Thomas M.

    2003-01-01

    The practical expansion of humans beyond low Earth orbit into near-Earth space and out into the solar system for exploration, commercialization, tourism, and colonization will require the effective utilization of whatever indigenous resources are available to make these endeavors economically feasible and capable of extended operations. This concept of ``living off the land'' is called In-Situ Resource Utilization (ISRU). The resources available for ISRU applications vary widely, depending upon the location. However, there are resources, technologies, and processes that are common to multiple destinations and ISRU-related applications. These resources range from carbon dioxide (CO2) and water vapor found in human habitats (surface & spacecraft) and in the Martian atmosphere, to water (ice and hydrated minerals) and various oxygen, carbon, and metal-bearing resources found on comets and asteroids, and in planetary surface materials at numerous destinations of interest (Moon, Mars, Titan, and Europa). Many parties are investigating the common technologies and processes to effectively extract and use these resources. This paper will discuss how ISRU is enabling for both near and far term human exploration missions, and present a summary of recent and on-going ISRU work sponsored by the NASA/Johnson Space Center. Technology development activities that will be described in detail include an advanced CO2 freezer acquisition system, a multi-fluid common bulkhead cryogenic storage tank, and a variety of microchannel chemical reactor concepts. Recent advanced Sabatier reactor concept development activities in preparation for later, end-to-end system testing will be described as well. This paper will also discuss an ISRU-based strategy to enable extensive robotic and human surface exploration operations and a related on-going demonstration program for a fuel cell based power plant for rover applications. Technology commonalities between ISRU, life support systems, and Extra

  3. Microchannel CO Methanation Reactors for Martian and Lunar ISRU

    SciTech Connect

    Dagle, Robert A.; Wegeng, Robert S.

    2008-07-05

    [Abstract] Microhannel technology offer significant advantages as a highly effective route to process intensification. NASA applications where size, weight, and process efficiency are key performance metrics, are very suitable applications. In situ resource utilization (ISRU) technologies is one such example. For use in a lunar carbothermal reduction process system a catalytic microchannel CO methanation reactor was developed. Design characteristics and operating performance evaluation for a multichannel reactor, approximately 4.5” X 0.5” X 1.0” in size, is discussed. Temperature, throughput, and mode of operation are variables explored. Two modes of operation were investigated: 1) under adiabatic conditions and 2) utilizing counter-current air cooling. The latter scenario offered a differential temperature profile which helped to improve performance. Demonstration of this concept is provided. Maintaining the inlet reactor temperature at 430oC the methane effluent composition output increased from 66.2% to 79.9% by introducing counter-flow air cooling. This allowed the exiting reactor temperature to decrease by ~ 100oC. Operating under such temperature differential conditions offeres exploitation of high kinetics at the hot front-end of the reactor while utilizing favorable thermodynamics at the cooler back-end. The highly efficient and compact nature of microchannel reactors make them uniquely suitable for such reaction engineering applications.

  4. RESOLVE: Bridge between early lunar ISRU and science objectives

    NASA Astrophysics Data System (ADS)

    Taylor, G.; Sanders, G.; Larson, W.; Johnson, K.

    2007-08-01

    THE NEED FOR RESOURCES: When mankind returns to the moon, there will be an aspect of the architecture that will totally change how we explore the solar system. We will take the first steps towards breaking our reliance on Earth supplied consumables by extracting resources from planetary bodies. Our first efforts in this area, known as In-Situ Resource Utilization (ISRU), will be to extract the abundant oxygen found in the lunar regolith. But the "holy grail" of lunar ISRU will be finding an exploitable source of lunar hydrogen. If we can find a source of extractable hydrogen, it would provide a foundation for true independence from Earth. With in-situ hydrogen (or water) and oxygen we can produce many of the major consumables needed to operate a lunar outpost. We would have water to drink, oxygen to breath, as well as rocket propellants and fuel cell reagents to enable extended access and operations on the moon. These items make up a huge percentage of the mass launched from the Earth. Producing them in-situ would significantly reduce the cost of operating a lunar outpost while increasing payload availability for science. PROSPECTING: The Lunar Prospector found evidence of elevated hydrogen at the lunar poles, and measurements made at these locations from the Clementine mission bistatic radar have been interpreted as correlating to water/ice concentrations. At the South Pole, there is reasonably strong correlation between the elevated areas of hydrogen and permanently shadowed craters. However, there is considerable debate on the form and concentration of this hydrogen since the orbiting satellites had limited resolution and their data can be interpreted in different ways. The varying interpretations are based on differing opinions and theories of lunar environment, evolution, and cometary bombardment within the lunar Science community. The only way to truly answer this question from both a Science and resource availability perspective is to go to the lunar poles

  5. Cassegrain Solar Concentrator System for ISRU Material Processing

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Macosko, Robert; Castle, Charles; Sacksteder, Kurt; Suzuki, Nantel H.; Mulherin, James

    2012-01-01

    A 0.5 m diameter Cassegrain concentrator was constructed as a means of providing highly concentrated sunlight for the demonstration processing of lunar simulated regolith and other NASA In-Situ Resource Utilization Project (ISRU) reaction processes. The concentrator is constructed of aluminum with a concentration ratio of approximately 3000 to 1. The concentrator focuses solar energy into a movable tray located behind the concentrator. This tray can hold simulated regolith or any other material and or device to be tested with concentrated solar energy. The tray is movable in one axis. A 2-axis extended optical system was also designed and fabricated. The extended optical system is added to the back of the primary concentrator in place of the moveable test tray and associated apparatus. With this optical system the focused sunlight can be extended from the back of the primary concentrator toward the ground with the added advantage of moving the focal point axially and laterally relative to the ground. This allows holding the focal point at a fixed position on the ground as the primary concentrator tracks the sun. Also, by design, the focal point size was reduced via the extended optics by a factor of 2 and results in a concentration ratio for the system of approximately 6,000 to 1.The designs of both optical systems are discussed. The results from simulated regolith melting tests are presented as well as the operational experience of utilizing the Cassegrain concentrator system.

  6. College biology students' conceptions related to the nature of biological knowledge: Implications for conceptual change

    NASA Astrophysics Data System (ADS)

    Ameny, Gloria Millie Apio

    knowledge or course was found to have a statistically significant influence on students' conceptions related to scientific methods, the scope and limits of biological knowledge, the importance of evolution in biology, and students' understanding of homologous and analogous structural features as products of divergent and convergent evolutionary processes. Findings of this study have implications for college biology teaching, student learning, and conceptual change among college biology students.

  7. ISRU: An Overview of NASA'S Current Development Activities and Long-Term Goals

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.; Nicholson, Leonard S. (Technical Monitor)

    2000-01-01

    The concept of "living off the land" by utilizing the indigenous resources of the Moon, Mars, or other potential sites of robotic and human exploration has been termed In-Situ Resource Utilization (ISRU). It is fundamental to any program of extended human presence and operation on other extraterrestrial bodies that we learn how to utilize the indigenous resources. The chief benefits of ISRU are that it can reduce the mass, cost, and risk of robotic and human exploration while providing capabilities that enable the commercial development of space. In January 1997, the American Institute of Aeronautics and Astronautics (AIAA) Space Processing Technical Committee released a position paper entitled, "Need for A NASA Indigenous Space Resource Utilization (ISRU) Program". Besides outlining some of the potential advantages of incorporating ISRU into Lunar and Mars human mission plans and providing an overview of technologies and processes of interest, the position paper concluded with a list of seven recommendations to NASA. This paper will examine the seven recommendations proposed and provide an overview of NASA's current ISRU development activities and possible long term goals with respect to these recommendations.

  8. ISRU: An Overview of NASA'S Current Development Activities and Long-Term Goals

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.; Nicholson, Leonard S. (Technical Monitor)

    2000-01-01

    The concept of "living off the land" by utilizing the indigenous resources of the Moon, Mars, or other potential sites of robotic and human exploration has been termed In-Situ Resource Utilization (ISRU). It is fundamental to any program of extended human presence and operation on other extraterrestrial bodies that we learn how to utilize the indigenous resources. The chief benefits of ISRU are that it can reduce the mass, cost, and risk of robotic and human exploration while providing capabilities that enable the commercial development of space. In January 1997, the American Institute of Aeronautics and Astronautics (AIAA) Space Processing Technical Committee released a position paper entitled, "Need for A NASA Indigenous Space Resource Utilization (ISRU) Program". Besides outlining some of the potential advantages of incorporating ISRU into Lunar and Mars human mission plans and providing an overview of technologies and processes of interest, the position paper concluded with a list of seven recommendations to NASA. This paper will examine the seven recommendations proposed and provide an overview of NASA's current ISRU development activities and possible long term goals with respect to these recommendations.

  9. Reactive oxygen species and vascular biology: implications in human hypertension.

    PubMed

    Touyz, Rhian M; Briones, Ana M

    2011-01-01

    Increased vascular production of reactive oxygen species (ROS; termed oxidative stress) has been implicated in various chronic diseases, including hypertension. Oxidative stress is both a cause and a consequence of hypertension. Although oxidative injury may not be the sole etiology, it amplifies blood pressure elevation in the presence of other pro-hypertensive factors. Oxidative stress is a multisystem phenomenon in hypertension and involves the heart, kidneys, nervous system, vessels and possibly the immune system. Compelling experimental and clinical evidence indicates the importance of the vasculature in the pathophysiology of hypertension and as such much emphasis has been placed on the (patho)biology of ROS in the vascular system. A major source for cardiovascular, renal and neural ROS is a family of non-phagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox), including the prototypic Nox2 homolog-based NADPH oxidase, as well as other Noxes, such as Nox1 and Nox4. Nox-derived ROS is important in regulating endothelial function and vascular tone. Oxidative stress is implicated in endothelial dysfunction, inflammation, hypertrophy, apoptosis, migration, fibrosis, angiogenesis and rarefaction, important processes involved in vascular remodeling in hypertension. Despite a plethora of data implicating oxidative stress as a causative factor in experimental hypertension, findings in human hypertension are less conclusive. This review highlights the importance of ROS in vascular biology and focuses on the potential role of oxidative stress in human hypertension.

  10. Reverse allostasis in biological systems: Minimal conditions and implications.

    PubMed

    Rezaei-Ghaleh, Nasrollah; Bakhtiari, Davood; Rashidi, Armin

    2017-08-07

    Biological control systems regulate the behavior of biological systems in a constantly changing environment. Homeostasis is the most widely studied outcome of biological control systems. Homeostatic systems maintain the system in its desired state despite variations in system parameters or the externally-determined input rates of their constituents, i.e. they have zero or near zero steady state error. On the other hand, allostatic systems are not resistant against environmental changes and the steady state level of their controlled variables responds positively to the changes in their input rates. Little is known, however, on the existence and frequency of reverse allostatic systems, where the steady state value of the controlled variable correlates negatively with the input rate of that variable. In the present study, we derive the minimal conditions for the existence and local stability of reverse allostatic systems, and demonstrate in examples of metabolic, pharmacological, pathophysiological and ecological systems that the reverse allostasis requirements are relatively non-stringent and may be satisfied in biological systems more commonly than usually thought. The possible existence of reverse allostatic systems in nature and their counter-intuitive implications in physiological systems, drug treatment, ecosystem management, and biological control are explored and testable predictions are made. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Molecular Biology of Gallbladder Cancer: Potential Clinical Implications

    PubMed Central

    Andrén-Sandberg, Åke

    2012-01-01

    Gallbladder cancer (GBC) is a common malignancy of the biliary tract and involves the changes in multiple oncogenes and multiple genetic genes. Since over the past decade there has been an advance in the knowledge of the genetic basis of cancer, mainly as a result of the rapid progression of molecular technology; however, conventional therapeutic approaches have not had much impact on the course of this aggressive neoplasm. Knowledge of the molecular biology of GBC is rapidly growing. Genetic alterations in GBC include adenosine triphosphate-binding cassette transporter ABCG8, membrane-bound enzyme ADAM-17 of multi-functional gene family, and other genes including p53, COX2, XPC, and RASSF1A. The advances in molecular biology have potential implications for the detection of this disease, using Synuclein-gamma, Syndecan-1, glycoprotein 72 (TAG-72), tumor endothelial marker 8 protein (TEM8) and TNF-alpha. The use of these molecular diagnostic methods is of clinical importance for the gene replacement therapy, genetic prodrug activation therapy, and antisense immunology technology for the treatment of malignancy. The author reviewed recent publications on PubMed, and summarized molecular biology of GBC, with an emphasis on features of potential clinical implications for diagnosis and management. PMID:23112962

  12. Water Electrolysis for In-Situ Resource Utilization (ISRU)

    NASA Technical Reports Server (NTRS)

    Lee, Kristopher A.

    2016-01-01

    Sending humans to Mars for any significant amount of time will require capabilities and technologies that enable Earth independence. To move towards this independence, the resources found on Mars must be utilized to produce the items needed to sustain humans away from Earth. To accomplish this task, NASA is studying In Situ Resource Utilization (ISRU) systems and techniques to make use of the atmospheric carbon dioxide and the water found on Mars. Among other things, these substances can be harvested and processed to make oxygen and methane. Oxygen is essential, not only for sustaining the lives of the crew on Mars, but also as the oxidizer for an oxygen-methane propulsion system that could be utilized on a Mars ascent vehicle. Given the presence of water on Mars, the electrolysis of water is a common technique to produce the desired oxygen. Towards this goal, NASA designed and developed a Proton Exchange Membrane (PEM) water electrolysis system, which was originally slated to produce oxygen for propulsion and fuel cell use in the Mars Atmosphere and Regolith COllector/PrOcessor for Lander Operations (MARCO POLO) project. As part of the Human Exploration Spacecraft Testbed for Integration and Advancement (HESTIA) project, this same electrolysis system, originally targeted at enabling in situ propulsion and power, operated in a life-support scenario. During HESTIA testing at Johnson Space Center, the electrolysis system supplied oxygen to a chamber simulating a habitat housing four crewmembers. Inside the chamber, oxygen was removed from the atmosphere to simulate consumption by the crew, and the electrolysis system's oxygen was added to replenish it. The electrolysis system operated nominally throughout the duration of the HESTIA test campaign, and the oxygen levels in the life support chamber were maintained at the desired levels.

  13. Thiolated arsenicals in arsenic metabolism: Occurrence, formation, and biological implications.

    PubMed

    Sun, Yuzhen; Liu, Guangliang; Cai, Yong

    2016-11-01

    Arsenic (As) is a notoriously toxic pollutant of health concern worldwide with potential risk of cancer induction, but meanwhile it is used as medicines for the treatment of different conditions including hematological cancers. Arsenic can undergo extensive metabolism in biological systems, and both toxicological and therapeutic effects of arsenic compounds are closely related to their metabolism. Recent studies have identified methylated thioarsenicals as a new class of arsenic metabolites in biological systems after exposure of inorganic and organic arsenicals, including arsenite, dimethylarsinic acid (DMA(V)), dimethylarsinous glutathione (DMA(III)GS), and arsenosugars. The increasing detection of thiolated arsenicals, including monomethylmonothioarsonic acid (MMMTA(V)), dimethylmonothioarsinic acid (DMMTA(V)) and its glutathione conjugate (DMMTA(V)GS), and dimethyldithioarsinic acid (DMDTA(V)) suggests that thioarsenicals may be important metabolites and play important roles in arsenic toxicity and therapeutic effects. Here we summarized the reported occurrence of thioarsenicals in biological systems, the possible formation pathways of thioarsenicals, and their toxicity, and discussed the biological implications of thioarsenicals on arsenic metabolism, toxicity, and therapeutic effects. Copyright © 2016. Published by Elsevier B.V.

  14. Sustaining Human Presence on Mars Using ISRU and a Reusable Lander

    NASA Technical Reports Server (NTRS)

    Arney, Dale C.; Jones, Christopher A.; Klovstad, Jordan J.; Komar, D.R.; Earle, Kevin; Moses, Robert; Shyface, Hilary R.

    2015-01-01

    This paper presents an analysis of the impact of ISRU (In-Site Resource Utilization), reusability, and automation on sustaining a human presence on Mars, requiring a transition from Earth dependence to Earth independence. The study analyzes the surface and transportation architectures and compared campaigns that revealed the importance of ISRU and reusability. A reusable Mars lander, Hercules, eliminates the need to deliver a new descent and ascent stage with each cargo and crew delivery to Mars, reducing the mass delivered from Earth. As part of an evolvable transportation architecture, this investment is key to enabling continuous human presence on Mars. The extensive use of ISRU reduces the logistics supply chain from Earth in order to support population growth at Mars. Reliable and autonomous systems, in conjunction with robotics, are required to enable ISRU architectures as systems must operate and maintain themselves while the crew is not present. A comparison of Mars campaigns is presented to show the impact of adding these investments and their ability to contribute to sustaining a human presence on Mars.

  15. An ISRU Propellant Production System to Fully Fuel a Mars Ascent Vehicle

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie E.; Paz, Aaron

    2017-01-01

    In-Situ Resource Utilization (ISRU) will enable the long term presence of humans beyond low earth orbit. Since 2009, oxygen production from the Mars atmosphere has been baselined as an enabling technology for Mars human exploration by NASA. However, using water from the Martian regolith in addition to the atmospheric CO2 would enable the production of both liquid Methane and liquid Oxygen, thus fully fueling a Mars return vehicle. A case study was performed to show how ISRU can support NASA's Evolvable Mars Campaign (EMC) using methane and oxygen production from Mars resources. A model was built and used to generate mass and power estimates of an end-to-end ISRU system including excavation and extraction water from Mars regolith, processing the Mars atmosphere, and liquefying the propellants. Even using the lowest yield regolith, a full ISRU system would weigh 1.7 mT while eliminating the need to transport 30 mT of ascent propellants from earth.

  16. Evolution of Regolith Feed Systems for Lunar ISRU 02 Production Plants

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Townsend, Ivan I., III; Mantovani, James G.; Metzger, Philip T.

    2010-01-01

    The In-Situ Resource Utilization (ISRU) project of the NASA Constellation Program, Exploration Technology Development Program (ETDP) has been engaged in the design and testing of various Lunar ISRU O2 production plant prototypes that can extract chemically bound oxygen from the minerals in the lunar regolith. This work demands that lunar regolith (or simulants) shall be introduced into the O2 production plant from a holding bin or hopper and subsequently expelled from the ISRU O2 production plant for disposal. This sub-system is called the Regolith Feed System (RFS) which exists in a variety of configurations depending on the O2 production plant oxygen being used (e.g. Hydrogen Reduction, Carbothermal, Molten Oxide Electrolysis). Each configuration may use a different technology and in addition it is desirable to have heat recuperation from the spent hot regolith as an integral part of the RFS. This paper addresses the various RFS and heat recuperation technologies and system configurations that have been developed under the NASA ISRU project since 2007. In addition current design solutions and lessons learned from reduced gravity flight testing will be discussed.

  17. Early In-Situ Resource Utilization (ISRU) Leading to Robust Sample Return and Human Exploration Missions

    NASA Astrophysics Data System (ADS)

    Sanders, G. B.; Larson, W. E.; Interbartolo, M. A.; Mueller, R. P.; Muscatello, A. C.

    2012-06-01

    ISRU to make propellants from Mars resources should be pursued early due to the benefits to Mars sample return and human exploration and synergism with lunar and Mars science objectives. Existing hardware can be used for a low cost/low risk demo 2018.

  18. Borrelidin B: isolation, biological activity, and implications for nitrile biosynthesis.

    PubMed

    Schulze, Christopher J; Bray, Walter M; Loganzo, Frank; Lam, My-Hanh; Szal, Teresa; Villalobos, Anabella; Koehn, Frank E; Linington, Roger G

    2014-11-26

    Borrelidin (1) is a nitrile-containing bacterially derived polyketide that is a potent inhibitor of bacterial and eukaryotic threonyl-tRNA synthetases. We now report the discovery of borrelidin B (2), a tetrahydro-borrelidin derivative containing an aminomethyl group in place of the nitrile functionality in borrelidin. The discovery of this new metabolite has implications for both the biosynthesis of the nitrile group and the bioactivity of the borrelidin compound class. Screening in the SToPS assay for tRNA synthetase inhibition revealed that the nitrile moiety is essential for activity, while profiling using our in-house image-based cytological profiling assay demonstrated that 2 retains biological activity by causing a mitotic stall, even in the absence of the nitrile motif.

  19. Biology, detection, and clinical implications of circulating tumor cells

    PubMed Central

    Joosse, Simon A; Gorges, Tobias M; Pantel, Klaus

    2015-01-01

    Cancer metastasis is the main cause of cancer-related death, and dissemination of tumor cells through the blood circulation is an important intermediate step that also exemplifies the switch from localized to systemic disease. Early detection and characterization of circulating tumor cells (CTCs) is therefore important as a general strategy to monitor and prevent the development of overt metastatic disease. Furthermore, sequential analysis of CTCs can provide clinically relevant information on the effectiveness and progression of systemic therapies (e.g., chemo-, hormonal, or targeted therapies with antibodies or small inhibitors). Although many advances have been made regarding the detection and molecular characterization of CTCs, several challenges still exist that limit the current use of this important diagnostic approach. In this review, we discuss the biology of tumor cell dissemination, technical advances, as well as the challenges and potential clinical implications of CTC detection and characterization. PMID:25398926

  20. Clinical and biological implications of driver mutations in myelodysplastic syndromes

    PubMed Central

    Papaemmanuil, Elli; Gerstung, Moritz; Malcovati, Luca; Tauro, Sudhir; Gundem, Gunes; Van Loo, Peter; Yoon, Chris J.; Ellis, Peter; Wedge, David C.; Pellagatti, Andrea; Shlien, Adam; Groves, Michael John; Forbes, Simon A.; Raine, Keiran; Hinton, Jon; Mudie, Laura J.; McLaren, Stuart; Hardy, Claire; Latimer, Calli; Della Porta, Matteo G.; O’Meara, Sarah; Ambaglio, Ilaria; Galli, Anna; Butler, Adam P.; Walldin, Gunilla; Teague, Jon W.; Quek, Lynn; Sternberg, Alex; Gambacorti-Passerini, Carlo; Cross, Nicholas C. P.; Green, Anthony R.; Boultwood, Jacqueline; Vyas, Paresh; Hellstrom-Lindberg, Eva; Bowen, David; Cazzola, Mario; Stratton, Michael R.

    2013-01-01

    Myelodysplastic syndromes (MDS) are a heterogeneous group of chronic hematological malignancies characterized by dysplasia, ineffective hematopoiesis and a variable risk of progression to acute myeloid leukemia. Sequencing of MDS genomes has identified mutations in genes implicated in RNA splicing, DNA modification, chromatin regulation, and cell signaling. We sequenced 111 genes across 738 patients with MDS or closely related neoplasms (including chronic myelomonocytic leukemia and MDS–myeloproliferative neoplasms) to explore the role of acquired mutations in MDS biology and clinical phenotype. Seventy-eight percent of patients had 1 or more oncogenic mutations. We identify complex patterns of pairwise association between genes, indicative of epistatic interactions involving components of the spliceosome machinery and epigenetic modifiers. Coupled with inferences on subclonal mutations, these data suggest a hypothesis of genetic “predestination,” in which early driver mutations, typically affecting genes involved in RNA splicing, dictate future trajectories of disease evolution with distinct clinical phenotypes. Driver mutations had equivalent prognostic significance, whether clonal or subclonal, and leukemia-free survival deteriorated steadily as numbers of driver mutations increased. Thus, analysis of oncogenic mutations in large, well-characterized cohorts of patients illustrates the interconnections between the cancer genome and disease biology, with considerable potential for clinical application. PMID:24030381

  1. Molecular biology of pancreatic cancer: potential clinical implications.

    PubMed

    Sakorafas, G H; Tsiotos, G G

    2001-01-01

    The development of cancer involves the accumulation of genetic changes. Over the past decade there has a been spectacular advance in the knowledge of the genetic basis of cancer, mainly as a result of the rapid progression of molecular technology. Pancreatic cancer is one of the most lethal cancers. Conventional therapeutic approaches have not had much impact on the course of this aggressive neoplasm. Knowledge of the molecular biology of pancreatic cancer has grown rapidly. Genetic alterations in pancreatic cancer include oncogene mutations (most commonly K-ras mutations), and tumour suppressor gene alterations (mainly p53, p16, DCC, etc.). These advances have potential implications for the management of this deadly disease. Identification of a hereditary genetic predisposition to pancreatic cancer has led to the formation of pancreatic cancer registries around the world, with voluntary screening of patients and siblings for the hereditary genetic defect. Asymptomatic population screening remains unrealistic, but the recognition of subpopulations at increased risk from pancreatic cancer, along with novel and sensitive detection techniques, means that targeted population screening is a step closer. Intensive research is performed in specialist laboratories to improve the diagnostic approach in patients with pancreatic cancer. The use of such molecular diagnostic methods is likely to expand. Molecular biology may also have a great impact on the treatment of pancreatic cancer, and many therapeutic approaches are being evaluated in clinical trials, including gene replacement therapy, genetic prodrug activation therapy, antisense immunology and peptide technology. The 'molecular age' has the promise of delivering still better results. This review summarises recent data relating to the molecular biology of pancreatic cancer, with emphasis on features that may be of clinical significance for diagnosis and/or therapy.

  2. Initial Biological Damage from Space Radiation: Implications for Development of Biological Countermeasures

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Paloski, William H. (Technical Monitor)

    1999-01-01

    Astronauts are exposed to high-energy nuclear particles originating from the galactic cosmic rays, high-energy protons trapped in the Earth's magnetic field or solar particle events, and secondary radiation produced by nuclear reactions. Important differences between conventional radiation including X-rays or gamma-rays, and high-energy nuclei occur at the level of initial damage to DNA and other potential biological target molecules, and to tissues. Such differences include a large fraction of the initial damage from high charge and energy (HZE) nuclear particles manifested as irreparable lesions including small- and large-scale DNA deletions. Also, low dose-rate exposures in space result in a heterogeneous population of damaged cells distinct from energetic photon irradiation of tissue. We present an overview of the initial biological damage and dose and dose-rate effects produced by ionizing radiation using track structure and nuclear reaction models. Implications of the differences in cellular and tissue damage between conventional radiation and space radiation for the development of biological countermeasures are discussed.

  3. Initial Biological Damage from Space Radiation: Implications for Development of Biological Countermeasures

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Paloski, William H. (Technical Monitor)

    1999-01-01

    Astronauts are exposed to high-energy nuclear particles originating from the galactic cosmic rays, high-energy protons trapped in the Earth's magnetic field or solar particle events, and secondary radiation produced by nuclear reactions. Important differences between conventional radiation including X-rays or gamma-rays, and high-energy nuclei occur at the level of initial damage to DNA and other potential biological target molecules, and to tissues. Such differences include a large fraction of the initial damage from high charge and energy (HZE) nuclear particles manifested as irreparable lesions including small- and large-scale DNA deletions. Also, low dose-rate exposures in space result in a heterogeneous population of damaged cells distinct from energetic photon irradiation of tissue. We present an overview of the initial biological damage and dose and dose-rate effects produced by ionizing radiation using track structure and nuclear reaction models. Implications of the differences in cellular and tissue damage between conventional radiation and space radiation for the development of biological countermeasures are discussed.

  4. Unravelling the biology of SCLC: implications for therapy.

    PubMed

    Sabari, Joshua K; Lok, Benjamin H; Laird, James H; Poirier, John T; Rudin, Charles M

    2017-09-01

    Small-cell lung cancer (SCLC) is an aggressive malignancy associated with a poor prognosis. First-line treatment has remained unchanged for decades, and a paucity of effective treatment options exists for recurrent disease. Nonetheless, advances in our understanding of SCLC biology have led to the development of novel experimental therapies. Poly [ADP-ribose] polymerase (PARP) inhibitors have shown promise in preclinical models, and are under clinical investigation in combination with cytotoxic therapies and inhibitors of cell-cycle checkpoints.Preclinical data indicate that targeting of histone-lysine N-methyltransferase EZH2, a regulator of chromatin remodelling implicated in acquired therapeutic resistance, might augment and prolong chemotherapy responses. High expression of the inhibitory Notch ligand Delta-like protein 3 (DLL3) in most SCLCs has been linked to expression of Achaete-scute homologue 1 (ASCL1; also known as ASH-1), a key transcription factor driving SCLC oncogenesis; encouraging preclinical and clinical activity has been demonstrated for an anti-DLL3-antibody-drug conjugate. The immune microenvironment of SCLC seems to be distinct from that of other solid tumours, with few tumour-infiltrating lymphocytes and low levels of the immune-checkpoint protein programmed cell death 1 ligand 1 (PD-L1). Nonetheless, immunotherapy with immune-checkpoint inhibitors holds promise for patients with this disease, independent of PD-L1 status. Herein, we review the progress made in uncovering aspects of the biology of SCLC and its microenvironment that are defining new therapeutic strategies and offering renewed hope for patients.

  5. Methylglyoxal in living organisms: chemistry, biochemistry, toxicology and biological implications.

    PubMed

    Kalapos, M P

    1999-11-22

    Despite the growing interest towards methylglyoxal and glyoxalases their real role in metabolic network is still obscure. In the light of developments several reviews have been published in this field mainly dealing with only a narrow segment of this research area. In this article a trial is made to present a comprehensive overview of methylglyoxal research, extending discussion from chemistry to biological implications by reviewing some important characteristics of methylglyoxal metabolism and toxicity in a wide variety of species, and emphasizing the action of methylglyoxal on energy production, free radical generation and cell killing. Special attention is paid to the discussion of alpha-oxoaldehyde production in the environment as a potential risk factor and to the possible role of this a-dicarbonyl in diseases. Concerning the interaction of methylglyoxal with biological macromolecules (DNA, RNA, proteins) an earlier review (Kalapos, Toxicology Letters, 73, 1994, 3-24) means a supplementation to this paper, thus hoping the avoidance of unnecessary bombast. The paper arrives at the conclusion that since the early stage of evolution the function of methylglyoxalase pathway has been related to carbohydrate metabolism, but its significance has been changed over the thousands of years. Namely, at the beginning of evolution methylglyoxalase path was essential for the reductive citric acid cycle as an anaplerotic route, while in the extant metabolism it concerns with the detoxification of methylglyoxal and plays some regulatory role in triose-phosphate household. As there is a tight junction between methylglyoxal and carbohydrate metabolism its pathological role in the events of the development of diabetic complications emerges in a natural manner and further progress is hoped in this field. In contrast, significant advancement cannot be expected in relation to cancer research.

  6. Component and System Sensitivity Considerations for Design of a Lunar ISRU Oxygen Production Plant

    NASA Technical Reports Server (NTRS)

    Linne, Diane L.; Gokoglu, Suleyman; Hegde, Uday G.; Balasubramaniam, Ramaswamy; Santiago-Maldonado, Edgardo

    2009-01-01

    Component and system sensitivities of some design parameters of ISRU system components are analyzed. The differences between terrestrial and lunar excavation are discussed, and a qualitative comparison of large and small excavators is started. The effect of excavator size on the size of the ISRU plant's regolith hoppers is presented. Optimum operating conditions of both hydrogen and carbothermal reduction reactors are explored using recently developed analytical models. Design parameters such as batch size, conversion fraction, and maximum particle size are considered for a hydrogen reduction reactor while batch size, conversion fraction, number of melt zones, and methane flow rate are considered for a carbothermal reduction reactor. For both reactor types the effect of reactor operation on system energy and regolith delivery requirements is presented.

  7. Lunar Polar In Situ Resource Utilization (ISRU) as a Stepping Stone for Human Exploration

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.

    2013-01-01

    A major emphasis of NASA is to extend and expand human exploration across the solar system. While specific destinations are still being discussed as to what comes first, it is imperative that NASA create new technologies and approaches that make space exploration affordable and sustainable. Critical to achieving affordable and sustainable exploration beyond low Earth orbit (LEO) are the development of technologies and approaches for advanced robotics, power, propulsion, habitats, life support, and especially, space resource utilization systems. Space resources and how to use them, often called In-Situ Resource Utilization (ISRU), can have a tremendous beneficial impact on robotic and human exploration of the Moon, Mars, Phobos, and Near Earth Objects (NEOs), while at the same time helping to solve terrestrial challenges and enabling commercial space activities. The search for lunar resources, demonstration of extraterrestrial mining, and the utilization of resource-derived products, especially from polar volatiles, can be a stepping stone for subsequent human exploration missions to other destinations of interest due to the proximity of the Moon, complimentary environments and resources, and the demonstration of critical technologies, processes, and operations. ISRU and the Moon: There are four main areas of development interest with respect to finding, obtaining, extracting, and using space resources: Prospecting for resources, Production of mission critical consumables like propellants and life support gases, Civil engineering and construction, and Energy production, storage, and transfer. The search for potential resources and the production of mission critical consumables are the primary focus of current NASA technology and system development activities since they provide the greatest initial reduction in mission mass, cost, and risk. Because of the proximity of the Moon, understanding lunar resources and developing, demonstrating, and implementing lunar ISRU

  8. Benefits of Mars ISRU Regolith Water Processing: A Case Study for the NASA Evolvable Mars Campaign

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie; Paz, Aaron; Mueller, Robert

    2016-01-01

    ISRU of Mars resources was baselined in 2009 Design Reference Architecture (DRA) 5.0, but only for Oxygen production using atmospheric CO2. The Methane (LCH4) needed for ascent propulsion of the Mars Ascent Vehicle (MAV) would need to be brought from Earth. However: Extracting water from the Martian Regolith enables the production of both Oxygen and Methane from Mars resources: Water resources could also be used for other applications including: Life support, radiation shielding, plant growth, etc. Water extraction was not baselined in DRA5.0 due to perceived difficulties and complexity in processing regolith. The NASA Evolvable Mars Campaign (EMC) requested studies to look at the quantitative benefits and trades of using Mars water ISRUPhase 1: Examined architecture scenarios for regolith water retrieval. Completed October 2015. Phase 2: Deep dive of one architecture concept to look at end-to-end system size, mass, power of a LCH4/LO2 ISRU production system

  9. An ISRU Propellant Production System to Fully Fuel a Mars Ascent Vehicle

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie; Paz, Aaron

    2017-01-01

    ISRU of Mars resources was base lined in 2009 Design Reference Architecture (DRA) 5.0, but only for Oxygen production using atmospheric CO2The Methane (LCH4) needed for ascent propulsion of the Mars Ascent Vehicle (MAV) would need to be brought from Earth. HOWEVER: Extracting water from the Martian Regolith enables the production of both Oxygen and Methane from Mars resources Water resources could also be used for other applications including: Life support, radiation shielding, plant growth, etc. Water extraction was not base lined in DRA5.0 due to perceived difficulties and complexity in processing regolith. The NASA Evolvable Mars Campaign (EMC) requested studies to look at the quantitative benefits and trades of using Mars water ISRU Phase 1: Examined architecture scenarios for regolith water retrieval. Completed October 2015Phase 2: Deep dive of one architecture concept to look at end-to-end system size, mass, power of a LCH4LO2 ISRU production system.Evolvable Mars CampaignPre-deployed Mars ascent vehicle (MAV)4 crew membersPropellants: Oxygen MethaneGenerate a system model to roll up mass power of a full ISRU system and enable parametric trade studies. Leverage models from previous studies and technology development programs Anchor with mass power performance from existing hardware. Whenever possible used reference-able (published) numbers for traceability.Modular approach to allow subsystem trades and parametric studies. Propellant mass needs taken from most recently published MAV study:Polsgrove, T. et al. (2015), AIAA2015-4416MAV engines operate at mixture ratios (oxygen: methane) between 3:1 and 3.5:1, whereas the Sabatier reactor produces at a 4:1 ratio. Therefore:Methane production is the driving requirement-Excess Oxygen will be produced.

  10. Understanding the biological and environmental implications of nanomaterials

    NASA Astrophysics Data System (ADS)

    Lin, Sijie

    of Nano-Eco and Nano-Bio interactions at the cellular level. (6) Chapter 6: Conclusions and future work. The overarching goal of this research is to advance our understanding on the fate of nanomaterials in biological and ecological systems. Knowledge obtained from this dissertation is expected to benefit future research on the implications and applications of engineered nanomaterials.

  11. Tutorial in oral antithrombotic therapy: Biology and dental implications

    PubMed Central

    Fakhri, Hamid R.; Janket, Sok J.; Baird, Alison E.; Dinnocenzo, Richard; Meurman, Jukka H.

    2013-01-01

    Objectives: Recent developments of new direct oral anticoagulants that target specific clotting factors necessitate understanding of coagulation biology. The objective of this tutorial is to offer dental professionals a review of coagulation mechanisms and the pharmacodynamics of the conventional and new oral anticoagulants. Also, we summarized the dental implications of the conventional and new anticoagulants. Method: We searched Medline using search terms “antithrombotic”, “antihemostasis” or “anticoagulation” and combined them with the search results of “dental”, “oral surgery” or “periodontal”. We restricted the results to “human” and “English”. Results: The early coagulation cascade, the new cell-based coagulation model, the pharmacokinetics and pharmacodynamics of conventional antithrombotics, and new oral anticoagulants were reviewed. The new direct factor Xa inhibitors and the direct thrombin inhibitor (s), called direct oral anticoagulants (DOAs) have rapid onset of action, fast elimination on cessation, and fewer drug-drug or drug-food interactions than warfarin. However, the lack of antidotes raises concerns that some dental procedures may trigger serious hemorrhagic events. Additionally, careful perioperative withdrawal and resumption protocols for the DOAs are reviewed, because DOAs’ blood levels are dependent on renal function. Also, various reversal strategies in the event of excessive bleedings are summarized. Perioperative management of dental patients taking new DOAs and conventional oral anticoagulants are also discussed. However, the perioperative strategies for DOAs are yet to be validated in randomized trials. Key words:Coagulation cascade, cell-based coagulation model, factor Xa inhibitors, direct thrombin inhibitors, prothrombin complex concentrates. PMID:23524440

  12. ISRU at a Lunar Outpost: Implementation and Opportunities for Partnerships and Commercial Development

    NASA Technical Reports Server (NTRS)

    Sanders, Gerald B.; Simon, Thomas; Larson, William E.; Santiago-Maldonado, Edgardo; Sacksteder, Kurt; Linne, Diane; Caruso, John; Easter, Robert

    2007-01-01

    The NASA Lunar Architecture Team (LAT), which was commissioned to help answer the question "how" will humans return to the Moon, and the Synthesis Team and the recently released Global Exploration Strategy, which was commissioned to help answer the question "why" will humans return to the Moon and go on to Mars have identified the ability to extract and use in-situ resources as important to extending human frontiers, reduce dependence on Earth, and further economic and commercial expansion into space. The extraction and processing of space resources into useful products, known as In-Situ Resource Utilization (ISRU), can have a substantial impact on mission and architecture concepts. In particular, the ability to make propellants, life support consumables, and fuel cell reagents can significantly reduce the cost, mass, and risk of sustained human activities beyond Earth. Potential lunar resources include solar wind implanted volatiles, vast quantities of metal and mineral oxides, possible water/ice at the poles, abundant solar energy, regions of permanent light and darkness, the vacuum of space itself, and even scavenging leftover descent propellants and/or trash and waste from human crew activities. Suitable processing can transform these raw resources into useful materials and products. The establishment of a human lunar Outpost, as proposed by NASA at the 2nd Space Exploration Conference in Houston in December 2006, opens up the possibility for the first time of breaking our reliance on Earth supplied consumables and learn to "live off the land". The ISRU phasing and capability incorporation strategy developed during LAT Phase I & II is based on the premise that while ISRU is a critical capability and key to successful implementation of the US Vision for Space Exploration, it is also an unproven capability for human lunar exploration and can not be put in the critical path of architecture success until it has been proven. Therefore, ISRU needs to take incremental

  13. Experimental Testing and Modeling of a Pneumatic Regolith Delivery System for ISRU

    NASA Technical Reports Server (NTRS)

    Santiago-Maldonado, Edgardo; Dominquez, Jesus A.; Mantovani, James G.

    2011-01-01

    Excavating and transporting planetary regolith are examples of surface activities that may occur during a future space exploration mission to a planetary body. Regolith, whether it is collected on the Moon, Mars or even an asteroid, consists of granular minerals, some of which have been identified to be viable resources that can be mined and processed chemically to extract useful by-products, such as oxygen, water, and various metals and metal alloys. Even the depleted "waste" material from such chemical processes may be utilized later in the construction of landing pads and protective structures at the site of a planetary base. One reason for excavating and conveying planetary regolith is to deliver raw regolith material to in-situ resource utilization (ISRU) systems. The goal of ISRU is to provide expendable supplies and materials at the planetary destination, if possible. An in-situ capability of producing mission-critical substances such as oxygen will help to extend the mission and its success, and will greatly lower the overall cost of a mission by either eliminating, or significantly reducing, the need to transport the same expendable materials from the Earth. In order to support the goals and objectives of present and future ISRU projects, NASA seeks technology advancements in the areas of regolith conveying. Such systems must be effective, efficient and provide reliable performance over long durations while being exposed to the harsh environments found on planetary surfaces. These conditions include contact with very abrasive regolith particulates, exposure to high vacuum or dry (partial) atmospheres, wide variations in temperature, reduced gravity, and exposure to space radiation. Regolith conveying techniques that combine reduced failure modes and low energy consumption with high material transfer rates will provide significant value for future space exploration missions to the surfaces of the moon, Mars and asteroids. Pneumatic regolith conveying has

  14. Opportunities and Strategies for Testing and Infusion of ISRU in the Evolvable Mars Campaign

    NASA Technical Reports Server (NTRS)

    Mueller, Robert P.; Sibille, Laurent; Mantovani, James; Sanders, Gerald B.; Jones, Christopher A.

    2015-01-01

    HE Evolvable Mars Campaign (EMC) is developing the plans and systems needed for a robust, evolutionary strategy to explore cis-lunar space, the Mars sphere of influence (including the moons of Mars), and the surface of Mars. Recently, the emphasis of NASA's plans has changed to focus on the prolonged pioneering of space, rather than focusing on a single crewed mission as the ultimate goal. A sustainable, pioneering vision of space would include in-situ resource utilization (ISRU) in multiple forms and at multiple destinations: atmospheric capture of Mars CO2 and/or volatiles for consumables and propellants, regolith for bulk and refined materials, and in-situ manufacturing at the Moon, Mars, and other bodies. These resources would enable a reduction in the logistical needs from Earth for future missions, thus preparing the way for a sustained presence on Mars. Although the EMC initially relies only on propellant production for the Mars ascent vehicle via ISRU, one of its primary objectives is to prospect at every EMC destination to understand the potential for ISRU; this will permit true pioneering to be enabled after the first crew arrives at Mars. Recent and ongoing analysis has considered the possible prospecting measurements that can be performed at the asteroid returned to cis-lunar space by the Asteroid Robotic Redirect Mission (ARRM), at the lunar surface, at Phobos and Deimos, and on the surface of Mars to identify available resources for future use. These opportunities will be available on missions currently in the Evolvable Mars Campaign construct, and will also facilitate the testing and demonstration of resource acquisition, processing, storage, and useage technologies that can play a role in later missions. This analysis has also led to the identification of several objectives that should be targeted during the missions building up to and including the initial crewed missions. These objectives are mapped to strategies for incorporating ISRU to support

  15. Book review: Conservation biology of Hawaiian forest birds: Implications for island avifauna

    USGS Publications Warehouse

    Engstrom, R. Todd; van Riper, Charles

    2010-01-01

    Review info: Conservation Biology of Hawaiian Forest Birds: Implications for Island Avifauna. By Thane K. Pratt, Carter T. Atkinson, Paul C. Banko, James D. Jacobi, and Bethany L. Woodworth, Eds., 2009. ISBN 978-0300141085, 707 pp.

  16. Reassessing Biological Threats: Implications for Cooperative Mitigation Strategies.

    PubMed

    Galloway, Summer Elise; Petzing, Stephanie Rachel; Young, Catharine Grace

    2015-01-01

    Multiple factors ranging from globalization to ecosystem disruption are presenting the global community with evolving biological threats to local, national, and global security that reach beyond the realm of traditional bioweapon threats. As a result, mitigation strategies have adapted necessarily to the increased diversity of biological threats. In general, response and preparedness strategies have largely shifted from being primarily reactive to traditional biological weapons to more proactive in nature. In this review, we briefly explore biological threats through a wider aperture, to embrace a greater appreciation of viral pathogens, antimicrobial resistance, and agricultural pathogens, and their potential to cause civil, economic, and political devastation. In addition, we discuss current mitigation strategies codified by the Global Health Security Agenda and the One Health paradigm as well as some of the available tools to assist with their sustainable implementation.

  17. Reassessing Biological Threats: Implications for Cooperative Mitigation Strategies

    PubMed Central

    Galloway, Summer Elise; Petzing, Stephanie Rachel; Young, Catharine Grace

    2015-01-01

    Multiple factors ranging from globalization to ecosystem disruption are presenting the global community with evolving biological threats to local, national, and global security that reach beyond the realm of traditional bioweapon threats. As a result, mitigation strategies have adapted necessarily to the increased diversity of biological threats. In general, response and preparedness strategies have largely shifted from being primarily reactive to traditional biological weapons to more proactive in nature. In this review, we briefly explore biological threats through a wider aperture, to embrace a greater appreciation of viral pathogens, antimicrobial resistance, and agricultural pathogens, and their potential to cause civil, economic, and political devastation. In addition, we discuss current mitigation strategies codified by the Global Health Security Agenda and the One Health paradigm as well as some of the available tools to assist with their sustainable implementation. PMID:26649289

  18. Self Organizing Systems and the Research Implications for Biological Systems

    NASA Astrophysics Data System (ADS)

    Denkins-Taffe, Lauren R.; Alfred, Marcus; Lindesay, James

    2008-03-01

    The knowledge gained from the human genome project, has provided an added opportunity to study the dynamical relationships within biological systems and can lead to an increased knowledge of diseases and subsequent drug discovery. Through computation, methods in which to rebuild these systems are being studied. These methods, which have first been applied to simpler systems: predator-prey, and self sustaining ecosystems can be applied to the study of microscopic biological systems.

  19. Lunar Contour Crafting: A Novel Technique for ISRU-Based Habitat Development

    NASA Technical Reports Server (NTRS)

    Khoshnevis, Behrokh; Bodiford, Melanie P.; Burks, Kevin H.; Ethridge, Ed; Tucker, Dennis; Kim, Won; Toutanji, Houssam; Fiske, Michael R.

    2005-01-01

    1. Habitat Structures at MSFC is one element of the In-Situ Fabrication and Repair (ISFR) Program: ISFR develops technologies for fabrication, repair and recycling of tools, parts, and habitats/structures using in-situ resources. ISRU - based habitat structures are considered Class III. 2. Habitat Structure Purpose: Develop Lunar and/or Martian habitat structures for manned missions that maximize the use of in-situ resources to address the following agency topics: bioastronautics critical path roadmap; strategic technical challenges defined in H&RT formulation plan: margins and redundancy; modularity, robotic network, space resource utilization; autonomy, affordable logistics pre-positioning.

  20. Mars Simulant Development for In-Situ Resource Utilization (ISRU) Applications

    NASA Technical Reports Server (NTRS)

    Ming, Doug

    2016-01-01

    Current design reference missions for the Evolvable Mars Campaign (EMC) call for the use of in-situ resources to enable human missions to the surface of Mars. One potential resource is water extracted from the Martian regolith. Current Mars' soil analogs (JSC Mars-1) have 5-10 times more water than typical regolith on Mars. Therefore, there is a critical need to develop Mars simulants to be used in ISRU applications that mimic the chemical, mineralogical, and physical properties of the Martian regolith.

  1. Indirect nontarget effects of host-specific biological control agents: Implications for biological control

    Treesearch

    Dean E. Pearson; Ragan M. Callaway

    2005-01-01

    Classical biological control of weeds currently operates under the assumption that biological control agents are safe (i.e., low risk) if they do not directly attack nontarget species. However, recent studies indicate that even highly host-specific biological control agents can impact nontarget species through indirect effects. This finding has profound...

  2. A Review of the Clinical Implications of Breast Cancer Biology.

    PubMed

    Parsa, Yekta; Mirmalek, Seyed Abbas; Kani, Fatemeh Elham; Aidun, Amir; Salimi-Tabatabaee, Seyed Alireza; Yadollah-Damavandi, Soheila; Jangholi, Ehsan; Parsa, Tina; Shahverdi, Ehsan

    2016-05-01

    Histologically similar tumors may have different prognoses and responses to treatment. These differences are due to molecular differences. Hence, in this review, the biological interaction of breast cancer in several different areas is discussed. In addition, the performance and clinical application of the most widely-recognized biomarkers, metastasis, and recurrences from a biological perspective and current global advances in these areas are addressed. This review provides the performance and clinical application of the most widely-recognized biomarkers, metastasis, and recurrences from the biological perspective and current global advances in these areas. PubMed, Scopus, and Google Scholar were searched comprehensively with combinations of the following keywords: "breast cancer," "biological markers," and "clinical." The definition of breast cancer, diagnostic methods, biological markers, and available treatment approaches were extracted from the literature. Estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER-2), and Ki-67 are the most well-known biological markers that have important roles in prognosis and response to therapeutic methods. Some studies showed the response of ER-positive and PR-negative tumors to anti-estrogenic treatment to be lower than ER-positive and PR-positive tumors. Patients with high expression of HER-2 and Ki-67 had a poor prognosis. In addition, recent investigations indicated the roles of new biomarkers, such as VEGF, IGF, P53 and P21, which are associated with many factors, such as age, race, and histological features. The objective of scientists, from establishing a relationship between cancer biology infrastructures with clinical manifestations, is to find new ways of prevention and progression inhibition and then possible introduction of less dangerous and better treatments to resolve this dilemma of human society.

  3. The Psychology of Schizophrenia: Implications for Biological and Psychotherapeutic Treatments.

    PubMed

    Dewan, Mantosh J

    2016-08-01

    The focus on recent advances in the neurobiology of schizophrenia has pushed aside the psychological understanding of the person with schizophrenia for several decades. However, a useful functional psychology of schizophrenia (in distinction to a psychological approach to symptoms) remains clinically important for several reasons: it is a core part of the bio-psycho-social formulation; it helps us understand and connect with persons with schizophrenia; and it provides a framework by which to organize our treatment efforts (both psychotherapeutic and particularly biological), which can improve adherence and outcomes. A coherent psychological model (the deficit model) based on object relations theory best explains all the biological, psychological, clinical, and sociocultural factors relevant to the understanding and treatment of persons with schizophrenia. A better understanding of a coherent psychology of persons with schizophrenia and provision of psychotherapies improves both the biological and psychotherapeutic treatment of persons with schizophrenia.

  4. Biological implications of magnesium salts at the molecular level.

    PubMed

    Theophanides, T

    1996-12-01

    The interaction of Mg2+ cations in biological systems is studied by using nucleic acid bases as the biological system. Magnesium salts, such as, MgCl2 6H2O, MgSO4. 7H2O and Mg(ClO4). XH2O have been employed in order to compare their complexation with cytosine and 1-methyl cytosine crystallize in water solutions. The reaction of the above magnesium salts with the two bases has been followed by attempting to crystallization the complexes formed at constant temperature and variable times of crystallization. The water solutions with the above reagents have also been followed by Fourier Transform infrared.

  5. The Development of ISRU and ISSE Technologies Leveraging Canadian Mining Expertise

    NASA Astrophysics Data System (ADS)

    Boucher, Dale S.; Richard, Jim; Dupuis, Erick

    2003-01-01

    F uture space missions to planetary bodies, both manned and robotic, will require the efficient utilization of in-situ resources to ensure longevity and success. In Situ Resources Utilization (ISRU) and In Situ Support Equipment (ISSE), while requiring the development of new technologies and methods for commodity extraction, will still rely upon some method of mining technology for the harvesting and pre-beneficiation of the raw materials prior to processing. The Northern Centre for Advanced Technologies Inc., in partnership with Electric Vehicle Controllers Ltd., is presently engaged in the development and adaptation of existing mining technologies and methodologies for use extra-terrestrially as pre cursor and enabling technologies for ISRU and for use as ISSE in support of longer term missions. More specifically, NORCAT and EVC, in partnership with MD Robotics and under contract to the Canadian Space Agency, are developing a drill and sample handler system for sub surface sampling of planetary bodies, specifically Mars. The partnership brings to the table some formidable world leading expertise in space robotics coupled with world leading expertise in mining technologies.

  6. Asteroid and Lava Tube In Situ Resource Utilization (ISRU) Prospecting Free Flyer Project

    NASA Technical Reports Server (NTRS)

    Falker, John; Zeitlin, Nancy; Mueller, Robert; Dupuis, Michael

    2015-01-01

    This project seeks to develop a small free flyer that can be used to safely and effectively prospect on an Asteroid while being controlled by the crew. This will enable the characterization of the Asteroid for the In Situ Resource Utilization (ISRU). Lava tubes can be explored remotely from the outside Asteroids can contain vast amounts of resources such as water for propellants and metals for feed stocks. Lava Tubes on Mars and the Moon may contain frozen volatile resources. Before the resources can be used, they must be found with a prospecting method. The NASA Agency Asteroid Grand Challenge seeks new ideas for Asteroid retrieval mission technologies for exploration and utilization of asteroids in a Distant Retrograde Orbit (DRO). This project will develop a small free flying platform that can be used to safely and effectively prospect on an Asteroid with limited autonomy while being controlled by the crew. This will enable the characterization of the Asteroid for ISRU. Lava tubes can be explored remotely from the outside as well using this same technology.

  7. Trade Study of Excavation Tools and Equipment for Lunar Outpost Development and ISRU

    NASA Astrophysics Data System (ADS)

    Mueller, R. P.; King, R. H.

    2008-01-01

    The NASA Lunar Architecture Team (LAT) has developed a candidate architecture to establish a lunar outpost that includes in-situ resource utilization (ISRU). Outpost development requires excavation for landing and launch sites, roads, trenches, foundations, radiation and thermal shielding, etc. Furthermore, ISRU requires excavation as feed stock for water processing and oxygen production plants. The design environment for lunar excavation tools and equipment including low gravity, cost of launching massive equipment, limited power, limited size, high reliability, and extreme temperatures is significantly different from terrestrial excavation equipment design environment. Consequently, the lunar application requires new approaches to developing excavation tools and equipment in the context of a systems engineering approach to building a Lunar Outpost. Several authors have proposed interesting and innovative general excavation approaches in the literature, and the authors of this paper will propose adaptations and/or new excavation concepts specific to the Lunar Outpost. The requirements for excavation from the LAT architecture will be examined and quantified with corresponding figures of merit and evaluation criteria. This paper will evaluate the proposed approaches using traditional decision making with uncertainty techniques.

  8. Resource Prospector (RP: )A Lunar Volatiles Prospecting and In-Situ Resource Utilization (ISRU) Demonstration Mission

    NASA Technical Reports Server (NTRS)

    Andrews, Daniel

    2016-01-01

    Efficient expansion of human presence beyond low-Earth orbit to asteroids and Mars will require the maximum possible use of local materials, so-called in-situ resources. The moon presents a unique destination to conduct robotic investigations that advance ISRU capabilities, as well as provide significant exploration and science value. Since the moons polar regions have confirmed the presence of volatiles, as revealed by the LCROSS and LRO missions, the next step is to understand the nature and distribution of those candidate resources and how they might be extracted. Recent studies have even indicated that if those volatiles are practically available for harvesting, they could be processed into propellants and human life-support resources, significantly reducing the cost of human missions to Mars maybe by as much as 50!Resource Prospector (RP) is an in-situ resource utilization (ISRU) technology demonstration mission under study by the NASA Human Exploration and Operations Mission Directorates (HEOMD). This clever mission is currently planned to launch as early as 2021 and will demonstrate extraction of oxygen, water and other volatiles, as well measure mineralogical content such as silicon and light metals from lunar regolith.

  9. ISRU 3D printing for habitats and structures on the Moon

    NASA Astrophysics Data System (ADS)

    Cowley, Aidan

    2016-07-01

    In-situ-resource utilisation (ISRU) in combination with 3D printing may evolve into a key technology for future exploration. Setting up a lunar facility could be made much simpler by using additive manufacturing techniques to build elements from local materials - this would drastically reduce mission mass requirements and act as an excellent demonstrator for ISRU on other planetary bodies. Fabricating structures and components using Lunar regolith is an area of interest for ESA, as evidenced by past successful General Studies Program (GSP) and ongoing technology development studies. In this talk we detail a number of projects looking into the behavior of Lunar regolith simulants, their compositional variants and approaches to sintering such material that are under-way involving EAC, ESTEC and DLR. We report on early studies into utilizing conventional thermal sintering approaches of simulants as well as microwave sintering of these compositions. Both techniques are candidates for developing a 3D printing methodology using Lunar regolith. It is known that the differences in microwave effects between the actual lunar soil and lunar simulants can be readily ascribed to the presence of nanophase metallic Fe, native to Lunar regolith but lacking in simulants. In compostions of simulant with increased Illmenite (FeTiO3) concentrations, we observe improved regolith response to microwave heating, and the readily achieved formation of a glassy melt in ambient atmosphere. The improved response relative to untreated simulant is likely owing to the increased Fe content in the powder mix.

  10. Biological implications of the Weibull and Gompertz models of aging.

    PubMed

    Ricklefs, Robert E; Scheuerlein, Alex

    2002-02-01

    Gompertz and Weibull functions imply contrasting biological causes of demographic aging. The terms describing increasing mortality with age are multiplicative and additive, respectively, which could result from an increase in the vulnerability of individuals to extrinsic causes in the Gompertz model and the predominance of intrinsic causes at older ages in the Weibull model. Experiments that manipulate extrinsic mortality can distinguish these biological models. To facilitate analyses of experimental data, we defined a single index for the rate of aging (omega) for the Weibull and Gompertz functions. Each function described the increase in aging-related mortality in simulated ages at death reasonably well. However, in contrast to the Weibull omega(W), the Gompertz omega(G) was sensitive to variation in the initial mortality rate independently of aging-related mortality. Comparisons between wild and captive populations appear to support the intrinsic-causes model for birds, but give mixed support for both models in mammals.

  11. Mode coupling in living systems: implications for biology and medicine.

    PubMed

    Swain, John

    2008-05-01

    Complex systems, and in particular biological ones, are characterized by large numbers of oscillations of widely differing frequencies. Various prejudices tend to lead to the assumption that such oscillators should generically be very weakly interacting. This paper reviews the basic ideas of linearity and nonlinearity as seen by a physicist, but with a view to biological systems. In particular, it is argued that large couplings between different oscillators of disparate frequencies are common, being present even in rather simple systems which are well-known in physics, although this issue is often glossed over. This suggests new experiments and investigations, as well as new approaches to therapies and human-environment interactions which, without the concepts described here, may otherwise seem unlikely to be interesting. The style of the paper is conversational with a minimum of mathematics, and no attempt at a complete list of references.

  12. Biological Implications of Dynamical Phases in Non-equilibrium Networks

    NASA Astrophysics Data System (ADS)

    Murugan, Arvind; Vaikuntanathan, Suriyanarayanan

    2016-03-01

    Biology achieves novel functions like error correction, ultra-sensitivity and accurate concentration measurement at the expense of free energy through Maxwell Demon-like mechanisms. The design principles and free energy trade-offs have been studied for a variety of such mechanisms. In this review, we emphasize a perspective based on dynamical phases that can explain commonalities shared by these mechanisms. Dynamical phases are defined by typical trajectories executed by non-equilibrium systems in the space of internal states. We find that coexistence of dynamical phases can have dramatic consequences for function vs free energy cost trade-offs. Dynamical phases can also provide an intuitive picture of the design principles behind such biological Maxwell Demons.

  13. Specific heat determination of plant barrier lipophilic components: biological implications.

    PubMed

    Casado, C G; Heredia, A

    2001-04-02

    The specific heat of isolated plant cuticles and their corresponding cuticular waxes have been measured for the physiological temperature in the range of 273-318 K at regular intervals. C(p) values ranged from 1.5 up to 4 J K(-1) g(-1) indicating a high cohesion, at the molecular level, of the molecular lipophilic components that constitute the plant cuticle. Second order phase transitions around 293 K, assigned to the cuticular matrix mainly constituted of the biopolyester cutin, have been detected and measured. Ecophysiological and physical implications of these thermodynamic data are discussed.

  14. CHEMICAL/BIOLOGICAL-CAPABLE RPA THREATS AND NATIONAL SECURITY IMPLICATIONS

    DTIC Science & Technology

    2016-02-07

    biological compounds. In 2014, a researcher at the University of Wisconsin reportedly constructed a new version of the flu virus from wild-avian- flu ...USAF) predicts that one third of its military and attack fighter planes will be unmanned within the next ten years.2 In addition, emerging micro and...and installations with respect to potential vulnerabilities. Third , it will expose viable gaps contained in the Chemical Weapons Convention (CWC) and

  15. Biological and mechanical implications of PEGylating proteins into hydrogel biomaterials.

    PubMed

    Gonen-Wadmany, Maya; Goldshmid, Revital; Seliktar, Dror

    2011-09-01

    Protein PEGylation has been successfully applied in pharmaceuticals and more recently in biomaterials development for making bioactive and structurally versatile hydrogels. Despite many advantages in this regard, PEGylation of proteins is also known to alter biological activity and modify biophysical characteristics in ways that may be detrimental to cells. The aim of this study was to evaluate the relative loss of biological compatibility associated with PEGylating a fibrinogen precursor into a hydrogel scaffold, in comparison to thrombin cross-linked fibrin hydrogels. Specifically, we investigated the consequences of conjugating fibrinogen with linear polyethtylene glycol (PEG) polymer chains (10 kDa) on the ability to cultivate neonatal human foreskin fibroblasts (HFFs) in 3-D. For this purpose, thrombin cross-linked fibrin (TCL-Fib) and PEGylated fibrinogen (PEG-Fib) gels were prepared with HFFs and cultured for up to seven days. The benchmark biological compatibility test was based on a combined assessment of cellular morphology, proliferation, actin expression, and matrix metalloproteinase (MMP) expression in the 3-D culture systems. The results showed correlations between modulus and proteolytic biodegradation in both materials, but no correlation between the mechanical properties and the ability of HFFs to remodel the microenvironment. A slight reduction of actin, MMPs, and spindled morphology of the cells in the PEG-Fib hydrogels indicated that the PEGylation process altered the biological compatibility of the fibrin. Nevertheless, the overall benchmark performance of the two materials demonstrated that PEGylated fibrinogen hydrogels still retains much to the inherent biofunctionality of the fibrin precursor when used as a scaffold for 3-D cell cultivation.

  16. Biological framework for soil aggregation: Implications for ecological functions.

    NASA Astrophysics Data System (ADS)

    Ghezzehei, Teamrat; Or, Dani

    2016-04-01

    Soil aggregation is heuristically understood as agglomeration of primary particles bound together by biotic and abiotic cementing agents. The organization of aggregates is believed to be hierarchical in nature; whereby primary particles bond together to form secondary particles and subsequently merge to form larger aggregates. Soil aggregates are not permanent structures, they continuously change in response to internal and external forces and other drivers, including moisture, capillary pressure, temperature, biological activity, and human disturbances. Soil aggregation processes and the resulting functionality span multiple spatial and temporal scales. The intertwined biological and physical nature of soil aggregation, and the time scales involved precluded a universally applicable and quantifiable framework for characterizing the nature and function of soil aggregation. We introduce a biophysical framework of soil aggregation that considers the various modes and factors of the genesis, maturation and degradation of soil aggregates including wetting/drying cycles, soil mechanical processes, biological activity and the nature of primary soil particles. The framework attempts to disentangle mechanical (compaction and soil fragmentation) from in-situ biophysical aggregation and provides a consistent description of aggregate size, hierarchical organization, and life time. It also enables quantitative description of biotic and abiotic functions of soil aggregates including diffusion and storage of mass and energy as well as role of aggregates as hot spots of nutrient accumulation, biodiversity, and biogeochemical cycles.

  17. Vascular biology of ageing—Implications in hypertension

    PubMed Central

    Harvey, Adam; Montezano, Augusto C.; Touyz, Rhian M.

    2015-01-01

    Ageing is associated with functional, structural and mechanical changes in arteries that closely resemble the vascular alterations in hypertension. Characteristic features of large and small arteries that occur with ageing and during the development of hypertension include endothelial dysfunction, vascular remodelling, inflammation, calcification and increased stiffness. Arterial changes in young hypertensive patients mimic those in old normotensive individuals. Hypertension accelerates and augments age-related vascular remodelling and dysfunction, and ageing may impact on the severity of vascular damage in hypertension, indicating close interactions between biological ageing and blood pressure elevation. Molecular and cellular mechanisms underlying vascular alterations in ageing and hypertension are common and include aberrant signal transduction, oxidative stress and activation of pro-inflammatory and pro-fibrotic transcription factors. Strategies to suppress age-associated vascular changes could ameliorate vascular damage associated with hypertension. An overview on the vascular biology of ageing and hypertension is presented and novel molecular mechanisms contributing to these processes are discussed. The complex interaction between biological ageing and blood pressure elevation on the vasculature is highlighted. This article is part of a Special Issue entitled: CV Ageing. PMID:25896391

  18. Interactions of nanomaterials and biological systems: implications to personalized nanomedicine☆

    PubMed Central

    Zhang, Xue-Qing; Xu, Xiaoyang; Bertrand, Nicolas; Pridgen, Eric; Swami, Archana; Farokhzad, Omid C.

    2012-01-01

    The application of nanotechnology to personalized medicine provides an unprecedented opportunity to improve the treatment of many diseases. Nanomaterials offer several advantages as therapeutic and diagnostic tools due to design flexibility, small sizes, large surface-to-volume ratio, and ease of surface modification with multivalent ligands to increase avidity for target molecules. Nanomaterials can be engineered to interact with specific biological components, allowing them to benefit from the insights provided by personalized medicine techniques. To tailor these interactions, a comprehensive knowledge of how nanomaterials interact with biological systems is critical. Herein, we discuss how the interactions of nanomaterials with biological systems can guide their design for diagnostic, imaging and drug delivery purposes. A general overview of nanomaterials under investigation is provided with an emphasis on systems that have reached clinical trials. Finally, considerations for the development of personalized nanomedicines are summarized such as the potential toxicity, scientific and technical challenges in fabricating them, and regulatory and ethical issues raised by the utilization of nanomaterials. PMID:22917779

  19. Vascular biology of ageing-Implications in hypertension.

    PubMed

    Harvey, Adam; Montezano, Augusto C; Touyz, Rhian M

    2015-06-01

    Ageing is associated with functional, structural and mechanical changes in arteries that closely resemble the vascular alterations in hypertension. Characteristic features of large and small arteries that occur with ageing and during the development of hypertension include endothelial dysfunction, vascular remodelling, inflammation, calcification and increased stiffness. Arterial changes in young hypertensive patients mimic those in old normotensive individuals. Hypertension accelerates and augments age-related vascular remodelling and dysfunction, and ageing may impact on the severity of vascular damage in hypertension, indicating close interactions between biological ageing and blood pressure elevation. Molecular and cellular mechanisms underlying vascular alterations in ageing and hypertension are common and include aberrant signal transduction, oxidative stress and activation of pro-inflammatory and pro-fibrotic transcription factors. Strategies to suppress age-associated vascular changes could ameliorate vascular damage associated with hypertension. An overview on the vascular biology of ageing and hypertension is presented and novel molecular mechanisms contributing to these processes are discussed. The complex interaction between biological ageing and blood pressure elevation on the vasculature is highlighted. This article is part of a Special Issue entitled: CV Ageing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Biological versus chronological ovarian age: implications for assisted reproductive technology

    PubMed Central

    Alviggi, Carlo; Humaidan, Peter; Howles, Colin M; Tredway, Donald; Hillier, Stephen G

    2009-01-01

    Background Women have been able to delay childbearing since effective contraception became available in the 1960s. However, fertility decreases with increasing maternal age. A slow but steady decrease in fertility is observed in women aged between 30 and 35 years, which is followed by an accelerated decline among women aged over 35 years. A combination of delayed childbearing and reduced fecundity with increasing age has resulted in an increased number and proportion of women of greater than or equal to 35 years of age seeking assisted reproductive technology (ART) treatment. Methods Literature searches supplemented with the authors' knowledge. Results Despite major advances in medical technology, there is currently no ART treatment strategy that can fully compensate for the natural decline in fertility with increasing female age. Although chronological age is the most important predictor of ovarian response to follicle-stimulating hormone, the rate of reproductive ageing and ovarian sensitivity to gonadotrophins varies considerably among individuals. Both environmental and genetic factors contribute to depletion of the ovarian oocyte pool and reduction in oocyte quality. Thus, biological and chronological ovarian age are not always equivalent. Furthermore, biological age is more important than chronological age in predicting the outcome of ART. As older patients present increasingly for ART treatment, it will become more important to critically assess prognosis, counsel appropriately and optimize treatment strategies. Several genetic markers and biomarkers (such as anti-Müllerian hormone and the antral follicle count) are emerging that can identify women with accelerated biological ovarian ageing. Potential strategies for improving ovarian response include the use of luteinizing hormone (LH) and growth hormone (GH). When endogenous LH levels are heavily suppressed by gonadotrophin-releasing hormone analogues, LH supplementation may help to optimize treatment

  1. Preface: Terrestrial Fieldwork to Support in situ Resource Utilization (ISRU) and Robotic Resource Prospecting for Future Activities in Space

    NASA Astrophysics Data System (ADS)

    Sanders, Gerald B.

    2015-05-01

    Finding, extracting, and using resources at the site of robotic and human exploration activities holds the promise of enabling sustainable and affordable exploration of the Moon, Mars, and asteroids, and eventually allow humans to expand their economy and habitation beyond the surface of the Earth. Commonly referred to as in situ Resource Utilization (ISRU), mineral and volatile resources found in space can be converted into oxygen, water, metals, fuels, and manufacturing and construction materials (such as plastics and concrete) for transportation, power, life support, habitation construction, and part/logistics manufacturing applications. For every kilogram of payload landed on the surface of the Moon or Mars, 7.5-11 kg of payload (mostly propellant) needs to be launched into low Earth orbit. Therefore, besides promising long-term self-sufficiency and infrastructure growth, ISRU can provide significant reductions in launch costs and the number of launches required. Key to being able to use space resources is knowing where they are located, how much is there, and how the resources are distributed. While ISRU holds great promise, it has also never been demonstrated in an actual space mission. Therefore, operations and hardware associated with each ISRU prospecting, excavation, transportation, and processing step must be examined, tested, and finally integrated to enable the end goal of using space resources in future human space missions.

  2. In-situ Resource Utilization (ISRU) to Support the Lunar Outpost and the Rationale for Precursor Missions

    NASA Technical Reports Server (NTRS)

    Simon, Thomas M.

    2008-01-01

    One of the ways that the Constellation Program can differ from Apollo is to employ a live-off-the-land or In-Situ Resource Utilization (ISRU) supported architecture. The options considered over the past decades for using indigenous materials have varied considerably in terms of what resources to attempt to acquire, how much to acquire, and what the motivations are to acquiring these resources. The latest NASA concepts for supporting the lunar outpost have considered many of these plans and compared these options to customers requirements and desires. Depending on the architecture employed, ISRU technologies can make a significant contribution towards a sustainable and affordable lunar outpost. While extensive ground testing will reduce some mission risk, one or more flight demonstrations prior to the first crew's arrival will build confidence and increase the chance that outpost architects will include ISRU as part of the early outpost architecture. This presentation includes some of the options for using ISRU that are under consideration for the lunar outpost, the precursor missions that would support these applications, and a notional timeline to allow the lessons learned from the precursor missions to support outpost hardware designs.

  3. Biological implications of polydimethylsiloxane-based microfluidic cell culture†

    PubMed Central

    Regehr, Keil J.; Domenech, Maribella; Koepsel, Justin T.; Carver, Kristopher C.; Ellison-Zelski, Stephanie J.; Murphy, William L.; Schuler, Linda A.; Alarid, Elaine T.; Beebe, David J.

    2009-01-01

    Polydimethylsiloxane (PDMS) has become a staple of the microfluidics community by virtue of its simple fabrication process and material attributes, such as gas permeability, optical transparency, and flexibility. As microfluidic systems are put toward biological problems and increasingly utilized as cell culture platforms, the material properties of PDMS must be considered in a biological context. Two properties of PDMS were addressed in this study: the leaching of uncured oligomers from the polymer network into microchannel media, and the absorption of small, hydrophobic molecules (i.e. estrogen) from serum-containing media into the polymer bulk. Uncured PDMS oligomers were detectable via MALDI-MS in microchannel media both before and after Soxhlet extraction of PDMS devices in ethanol. Additionally, PDMS oligomers were identified in the plasma membranes of NMuMG cells cultured in PDMS microchannels for 24 hours. Cells cultured in extracted microchannels also contained a detectable amount of uncured PDMS. It was shown that MCF-7 cells seeded directly on PDMS inserts were responsive to hydrophilic prolactin but not hydrophobic estrogen, reflecting its specificity for absorbing small, hydrophobic molecules; and the presence of PDMS floating in wells significantly reduced cellular response to estrogen in a serum-dependent manner. Quantification of estrogen via ELISA revealed that microchannel estrogen partitioned rapidly into the surrounding PDMS to a ratio of approximately 9:1. Pretreatments such as blocking with serum or pre-absorbing estrogen for 24 hours did not affect estrogen loss from PDMS-based microchannels. These findings highlight the importance of careful consideration of culture system properties when determining an appropriate environment for biological experiments. PMID:19606288

  4. Biological implications of polydimethylsiloxane-based microfluidic cell culture.

    PubMed

    Regehr, Keil J; Domenech, Maribella; Koepsel, Justin T; Carver, Kristopher C; Ellison-Zelski, Stephanie J; Murphy, William L; Schuler, Linda A; Alarid, Elaine T; Beebe, David J

    2009-08-07

    Polydimethylsiloxane (PDMS) has become a staple of the microfluidics community by virtue of its simple fabrication process and material attributes, such as gas permeability, optical transparency, and flexibility. As microfluidic systems are put toward biological problems and increasingly utilized as cell culture platforms, the material properties of PDMS must be considered in a biological context. Two properties of PDMS were addressed in this study: the leaching of uncured oligomers from the polymer network into microchannel media, and the absorption of small, hydrophobic molecules (i.e. estrogen) from serum-containing media into the polymer bulk. Uncured PDMS oligomers were detectable via MALDI-MS in microchannel media both before and after Soxhlet extraction of PDMS devices in ethanol. Additionally, PDMS oligomers were identified in the plasma membranes of NMuMG cells cultured in PDMS microchannels for 24 hours. Cells cultured in extracted microchannels also contained a detectable amount of uncured PDMS. It was shown that MCF-7 cells seeded directly on PDMS inserts were responsive to hydrophilic prolactin but not hydrophobic estrogen, reflecting its specificity for absorbing small, hydrophobic molecules; and the presence of PDMS floating in wells significantly reduced cellular response to estrogen in a serum-dependent manner. Quantification of estrogen via ELISA revealed that microchannel estrogen partitioned rapidly into the surrounding PDMS to a ratio of approximately 9:1. Pretreatments such as blocking with serum or pre-absorbing estrogen for 24 hours did not affect estrogen loss from PDMS-based microchannels. These findings highlight the importance of careful consideration of culture system properties when determining an appropriate environment for biological experiments.

  5. Possible surface reactions on Mars - Implications for Viking biology results

    NASA Technical Reports Server (NTRS)

    Ponnamperuma, C.; Shimoyama, A.; Yamada, M.; Hobo, T.; Pal, R.

    1977-01-01

    The results of two of the three biology experiments carried out on the Viking Mars landers have been simulated. The mixture of organic compounds labeled with carbon-14 used on Mars released carbon dioxide containing carbon-14 when reacted with a simulated Martian surface and atmosphere exposed to ultraviolet light (labeled release experiment). Oxygen was released when metal peroxides or superoxides were treated with water (gas exchange experiment). The simulations suggest that the results of these two Viking experiments can be explained on the basis of reactions of the Martian surface and atmosphere.

  6. Multiple biological properties of macelignan and its pharmacological implications.

    PubMed

    Paul, Saswati; Hwang, Jae Kwan; Kim, Hahn Young; Jeon, Won Kyung; Chung, ChiHye; Han, Jung-Soo

    2013-03-01

    Macelignan found in the nutmeg mace of Myristica fragrans obtains increasing attention as a new avenue in treating various diseases. Macelignan has been shown to possess a spectrum of pharmacological activities, including anti-bacterial, anti-inflammatory, anti-cancer, anti-diabetes, and hepatoprotective activities; recently, it has also been shown to have neuroprotective activities. This review summarizes the current research on the biological effects of macelignan derived from M. fragrans, with emphasis on the importance in understanding and treating complex diseases such as cancer and Alzheimer's disease.

  7. Implications of Oxygen Homeostasis for Tumor Biology and Treatment.

    PubMed

    Garvalov, Boyan K; Acker, Till

    2016-01-01

    Tumors serve as a prototype system to study the role of the hypoxic microenvironment and gain insight in the regulation oxygen homeostasis. A series of biochemical and cell biological studies have significantly extended our knowledge of how tumor cells activate key regulatory mechanisms of oxygen homeostasis not only to adapt to the hostile tumor microenvironment but also to acquire a more aggressive tumor phenotype. Reduced oxygen levels and tumor-specific genetic alterations synergistically drive tumor progression by activating a key transcriptional system, the hypoxia inducible factors (HIFs). HIFs trigger a set of adaptive responses commonly associated with tumor malignancy including tumor angiogenesis, a shift in metabolism, proliferation, invasion, and metastasis. We and others could demonstrate that cancer stem cells are controlled by HIFs within a hypoxic niche, establishing an intriguing link between the well known function of hypoxia in tumor growth and stem cell biology. Additionally, HIF activation potentially conveys resistance to current tumor therapies including the evasive resistance phenotype observed after anti-angiogenic treatment. Together, these findings provide strong evidence that activation of the HIF system is a decisive step in cancer progression that critically shapes therapy response and clinical outcome. Recent insight into the precise mechanisms of oxygen sensing and signalling has offered new promising and potentially selective strategies to counteract this crucial pathway.

  8. Biosynthesis, processing and secretion of von Willebrand factor: biological implications.

    PubMed

    de Wit, T R; van Mourik, J A

    2001-06-01

    von Willebrand factor is a multimeric plasma glycoprotein that is required for normal haemostasis. von Willebrand factor is synthesized by endothelial cells and megakaryocytes, and originates from its precursor pro-von Willebrand factor. The endoproteolytic processing of pro-von Willebrand factor results in mature von Willebrand factor and von Willebrand factor propeptide (also known as von Willebrand Ag II). In endothelial cells, the propeptide controls the polymerization and subsequent targeting of von Willebrand factor to the storage vesicles, the so-called Weibel-Palade bodies. Upon stimulation of the endothelial cells, the Weibel-Palade bodies are translocated to the plasma membrane of the cell, and mature von Willebrand factor and its propeptide are co-secreted. After release, these polypeptides have divergent fates and serve different biological functions. Mature von Willebrand factor both controls platelet adhesion and aggregation at sites of vascular injury and acts as a chaperone protein for coagulation factor VIII. The von Willebrand factor propeptide may serve a role in modulating inflammatory processes. This still growing body of information indicates that the biological function of the von Willebrand factor gene product is more diverse than was previously thought.

  9. The paradox of the parasites: implications for biological invasion.

    PubMed Central

    Drake, John M

    2003-01-01

    The enemy-release hypothesis for biological invasions supposes that invasive species may be more successful in their introduced ranges than in their native ranges owing to the absence of coevolved natural enemies. Recent studies supporting this hypothesis have found that introduced plants and animals are less parasitized in their introduced ranges than in their native ranges. Expanding on this theory, I hypothesize that the role of enemy release may differ among the introduction, establishment and spread phases of an invasion. I present a simple model indicating that parasite release is unlikely to greatly affect the chance of establishment in populations with and without an immune subpopulation. The specific numerical relationship between the number of individuals introduced and the chance of establishment depends on a relationship between virulence, here conceptualized as the chance for the extinction of a lineage, and the fraction of the population infected at introduction. These results support the idea of a 'filter effect' in which different biological processes regulate the different phases of an invasion. PMID:14667361

  10. Hepatitis B virus genetic variants: biological properties and clinical implications

    PubMed Central

    Tong, Shuping; Li, Jisu; Wands, Jack R; Wen, Yu-mei

    2013-01-01

    Hepatitis B virus (HBV) causes a chronic infection in 350 million people worldwide and greatly increases the risk of liver cirrhosis and hepatocellular carcinoma. The majority of chronic HBV carriers live in Asia. HBV can be divided into eight genotypes with unique geographic distributions. Mutations accumulate during chronic infection or in response to external pressure. Because HBV is an RNA-DNA virus the emergence of drug resistance and vaccine escape mutants has become an important clinical and public health concern. Here, we provide an overview of the molecular biology of the HBV life cycle and an evaluation of the changing role of hepatitis B e antigen (HBeAg) at different stages of infection. The impact of viral genotypes and mutations/deletions in the precore, core promoter, preS, and S gene on the establishment of chronic infection, development of fulminant hepatitis and liver cancer is discussed. Because HBV is prone to mutations, the biological properties of drug-resistant and vaccine escape mutants are also explored. PMID:26038454

  11. Trauma and Stem Cells: Biology and Potential Therapeutic Implications

    PubMed Central

    Thurairajah, Kabilan; Broadhead, Matthew L.; Balogh, Zsolt J.

    2017-01-01

    Trauma may cause irreversible tissue damage and loss of function despite current best practice. Healing is dependent both on the nature of the injury and the intrinsic biological capacity of those tissues for healing. Preclinical research has highlighted stem cell therapy as a potential avenue for improving outcomes for injuries with poor healing capacity. Additionally, trauma activates the immune system and alters stem cell behaviour. This paper reviews the current literature on stem cells and its relevance to trauma care. Emphasis is placed on understanding how stem cells respond to trauma and pertinent mechanisms that can be utilised to promote tissue healing. Research involving notable difficulties in trauma care such as fracture non-union, cartilage damage and trauma induced inflammation is discussed further. PMID:28272352

  12. Trauma and Stem Cells: Biology and Potential Therapeutic Implications.

    PubMed

    Thurairajah, Kabilan; Broadhead, Matthew L; Balogh, Zsolt J

    2017-03-07

    Trauma may cause irreversible tissue damage and loss of function despite current best practice. Healing is dependent both on the nature of the injury and the intrinsic biological capacity of those tissues for healing. Preclinical research has highlighted stem cell therapy as a potential avenue for improving outcomes for injuries with poor healing capacity. Additionally, trauma activates the immune system and alters stem cell behaviour. This paper reviews the current literature on stem cells and its relevance to trauma care. Emphasis is placed on understanding how stem cells respond to trauma and pertinent mechanisms that can be utilised to promote tissue healing. Research involving notable difficulties in trauma care such as fracture non-union, cartilage damage and trauma induced inflammation is discussed further.

  13. Chemical Consequences of Radioactive Decay and their Biological Implications.

    PubMed

    DeJesus, Onofre T

    2017-07-14

    The chemical effects of radioactive decay arise from (1) transmutation, (2) formation of charged daughter nuclei, (3) recoil of the daughter nuclei, (4) electron "shakeoff" phenomenon and (5) vacancy cascade in decays via electron capture and internal conversion. This review aims to reiterate what has been known for a long time regarding the chemical consequences of radioactive decay and gives a historical perspective to the observations that led to their elucidation. The energetics of the recoil process in each decay mode is discussed in relation to the chemical bond between the decaying nucleus and the parent molecule. Special attention is given to the biological effects of the Auger process following decay by electron capture and internal conversion because of their possible utility in internal radiotherapy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Angiogenesis in Spontaneous Tumors and Implications for Comparative Tumor Biology

    PubMed Central

    Benazzi, C.; Al-Dissi, A.; Chau, C. H.; Figg, W. D.; Sarli, G.; de Oliveira, J. T.; Gärtner, F.

    2014-01-01

    Blood supply is essential for development and growth of tumors and angiogenesis is the fundamental process of new blood vessel formation from preexisting ones. Angiogenesis is a prognostic indicator for a variety of tumors, and it coincides with increased shedding of neoplastic cells into the circulation and metastasis. Several molecules such as cell surface receptors, growth factors, and enzymes are involved in this process. While antiangiogenic therapy for cancer has been proposed over 20 years ago, it has garnered much controversy in recent years within the scientific community. The complex relationships between the angiogenic signaling cascade and antiangiogenic substances have indicated the angiogenic pathway as a valid target for anticancer drug development and VEGF has become the primary antiangiogenic drug target. This review discusses the basic and clinical perspectives of angiogenesis highlighting the importance of comparative biology in understanding tumor angiogenesis and the integration of these model systems for future drug development. PMID:24563633

  15. Understanding the biology of melanoma and therapeutic implications

    PubMed Central

    Sullivan, Ryan J; Fisher, David E

    2014-01-01

    From 1976 – 2010, the US FDA approved only two medications for the treatment of metastatic melanoma, dacarbazine and high-dose interleukin 2. Between 2011–13, four agents were approved (ipilimumab, vemurafenib, dabrafenib, trametinib) and other therapies have shown great promise in clinical trials. This startling progress has been made possible by the groundbreaking efforts of basic scientists and the vision and innovation of translational and clinical investigators. Fundamental discoveries such as the identification of oncogenic mutations in the majority melanomas, the elucidation of the molecular signaling resultant from these mutations, and the revelation that a number of cell surface molecules serve as regulators of immune activation, have all been instrumental to this progress. This chapter provides a summary of the molecular pathogenesis of melanoma by reviewing the relevant melanocyte biology and molecular signaling used by melanoma, describes the current efforts to target oncogene driven signaling, and presents the rationale for combining immune and molecular targeting. PMID:24880940

  16. Trends and implications of biological analyses for agricultural operations

    SciTech Connect

    Ash, D.H.; Salladay, D.G.

    1994-10-01

    State and federal legislatures, regulatory agencies, the agricultural community, and the public at large have increasing concerns about groundwater contamination and other environmental issues. The U.S. Congress has requested all federal agencies working with agriculture to address these issues. Even with current pressures to {open_quotes}cut government spending,{close_quotes} public pressure prevails to clean up polluted sites and to prevent future contamination. Farmers, agrichemical dealers and producers, and related trade associations have voiced concern about regulations affecting their industries. Over the last three decades positive changes have evolved in the disposal or final resolution of agricultural wastes from indiscriminate disposal on land and in water, through regulated land filling and incineration to a point where biological treatment/remediation strategies are coming to the forefront. These biological strategies bring with them different requirements for analytical methods. In March of this year the Environmental Protection Agency (EPA) and ARA organized a work group which met in Cincinnati, Ohio, to discuss the bioremediation of pesticide-laden soil. This work group consisted of EPA researchers, regulators, and administrators; state ag-environmental technologists and program directors; ag-chemical producer, remediation program managers, university ag researchers, USDA researchers, and TVA technologists. Consensus was quickly obtained on the utter unaffordability of current chemical and thermal treatment schemes for agricultural wastes, contaminated soils, and rinsewaters. Consensus was also reached that conventional analytical methods are too expensive and complicated for use in the field demonstration/application of the bioremediation-type processes. Thus the group recommended and supported field agrichemical dealer demonstrations of landfarming and composting with an emphasis on the need to develop low cost, easy toxicological measurements.

  17. Implications of pyrosequencing error correction for biological data interpretation.

    PubMed

    Bakker, Matthew G; Tu, Zheng J; Bradeen, James M; Kinkel, Linda L

    2012-01-01

    There has been a rapid proliferation of approaches for processing and manipulating second generation DNA sequence data. However, users are often left with uncertainties about how the choice of processing methods may impact biological interpretation of data. In this report, we probe differences in output between two different processing pipelines: a de-noising approach using the AmpliconNoise algorithm for error correction, and a standard approach using quality filtering and preclustering to reduce error. There was a large overlap in reads culled by each method, although AmpliconNoise removed a greater net number of reads. Most OTUs produced by one method had a clearly corresponding partner in the other. Although each method resulted in OTUs consisting entirely of reads that were culled by the other method, there were many more such OTUs formed in the standard pipeline. Total OTU richness was reduced by AmpliconNoise processing, but per-sample OTU richness, diversity and evenness were increased. Increases in per-sample richness and diversity may be a result of AmpliconNoise processing producing a more even OTU rank-abundance distribution. Because communities were randomly subsampled to equalize sample size across communities, and because rare sequence variants are less likely to be selected during subsampling, fewer OTUs were lost from individual communities when subsampling AmpliconNoise-processed data. In contrast to taxon-based diversity estimates, phylogenetic diversity was reduced even on a per-sample basis by de-noising, and samples switched widely in diversity rankings. This work illustrates the significant impacts of processing pipelines on the biological interpretations that can be made from pyrosequencing surveys. This study provides important cautions for analyses of contemporary data, for requisite data archiving (processed vs. non-processed data), and for drawing comparisons among studies performed using distinct data processing pipelines.

  18. The implications of the precautionary principle for biological monitoring

    NASA Astrophysics Data System (ADS)

    Macgarvin, M.

    1995-03-01

    Marine biological monitoring programmes frequently attempt to determine “safe” levels of contamination, based on assumptions about the assimilative capacity of the environment. This paper argues that such assumptions lack scientific rigour, and do not form the basis upon which a precautionary policy can be built. It notes the problems associated with assessing toxicological effects, but centres its attention on the crucial (yet far less discussed) weaknesses in theoretical ecology that make it extremely unlikely that biological monitoring can determine safe levels of contamination that leave ecosystems unaffected. It is argued that many marine biologists, if pressed, would concede these shortcomings but believe that, in the face of the technical difficulties and high costs of pollution prevention, we have no choice but to use such methods. This paper argues, with examples, that pollution prevention, often with considerable economic savings, is becoming a reality for even the most problematic substances. The difficulty is that the development of “clean production” methods lie outside the sphere of interest of those carrying out monitoring, so that measures that attempt to determine safe levels of contamination continue to be advocated. This gulf needs to be bridged so that the continuation of monitoring programmes that are part of dilute and disperse policies become regarded as inappropriate, indeed unethical. The paper concludes that this does not mean the end of marine monitoring. Instead, reliable methods for assessing physical levels of contamination will be required to determine whether the reduction targets set—as part of the introduction of clean production—are being met. Formidable difficulties will remain, requiring a precautious approach. Nevertheless, monitoring will no longer carry the burden of attempting to demonstrate that a particular level of environmental contamination is safe, which is currently destroying its scientific credibility.

  19. Ocean Biological Pump Sensitivities and Implications for Climate Change Impacts

    NASA Technical Reports Server (NTRS)

    Romanou, Anastasia

    2013-01-01

    The ocean is one of the principal reservoirs of CO2, a greenhouse gas, and therefore plays a crucial role in regulating Earth's climate. Currently, the ocean sequesters about a third of anthropogenic CO2 emissions, mitigating the human impact on climate. At the same time, the deeper ocean represents the largest carbon pool in the Earth System and processes that describe the transfer of carbon from the surface of the ocean to depth are intimately linked to the effectiveness of carbon sequestration.The ocean biological pump (OBP), which involves several biogeochemical processes, is a major pathway for transfer of carbon from the surface mixed layer into the ocean interior. About 75 of the carbon vertical gradient is due to the carbon pump with only 25 attributed to the solubility pump. However, the relative importance and role of the two pumps is poorly constrained. OBP is further divided to the organic carbon pump (soft tissue pump) and the carbonate pump, with the former exporting about 10 times more carbon than the latter through processes like remineralization.Major uncertainties about OBP, and hence in the carbon uptake and sequestration, stem from uncertainties in processes involved in OBP such as particulate organicinorganic carbon sinkingsettling, remineralization, microbial degradation of DOC and uptakegrowth rate changes of the ocean biology. The deep ocean is a major sink of atmospheric CO2 in scales of hundreds to thousands of years, but how the export efficiency (i.e. the fraction of total carbon fixation at the surface that is transported at depth) is affected by climate change remains largely undetermined. These processes affect the ocean chemistry (alkalinity, pH, DIC, particulate and dissolved organic carbon) as well as the ecology (biodiversity, functional groups and their interactions) in the ocean. It is important to have a rigorous, quantitative understanding of the uncertainties involved in the observational measurements, the models and the

  20. The Microbiome of Animals: Implications for Conservation Biology

    PubMed Central

    Bahrndorff, Simon; Alemu, Tibebu; Alemneh, Temesgen; Lund Nielsen, Jeppe

    2016-01-01

    In recent years the human microbiome has become a growing area of research and it is becoming clear that the microbiome of humans plays an important role for human health. Extensive research is now going into cataloging and annotating the functional role of the human microbiome. The ability to explore and describe the microbiome of any species has become possible due to new methods for sequencing. These techniques allow comprehensive surveys of the composition of the microbiome of nonmodel organisms of which relatively little is known. Some attention has been paid to the microbiome of insect species including important vectors of pathogens of human and veterinary importance, agricultural pests, and model species. Together these studies suggest that the microbiome of insects is highly dependent on the environment, species, and populations and affects the fitness of species. These fitness effects can have important implications for the conservation and management of species and populations. Further, these results are important for our understanding of invasion of nonnative species, responses to pathogens, and responses to chemicals and global climate change in the present and future. PMID:27195280

  1. Chaos, population biology, and epidemiology: some research implications.

    PubMed

    Philippe, P

    1993-08-01

    In this article I aim to provide some feeling of the new paradigm of disease causation (chaos) as it applies to the field of population biology and epidemiology. A secondary objective is to show, with the aid of qualitative methods, how one can approach chaos in time-series data. The multifactorial stochastic paradigm of causation is contrasted with the new deterministic approach. This approach is embedded in the theory of nonlinear system dynamics. Chaos implies that randomness is intrinsic to a nonlinear deterministic system; this is true despite the extent of knowledge of the intervening causes and, ultimately, despite determinism. Three research avenues are discussed in depth from the standpoint of chaos theory. First, the topic of sporadic epidemics is dealt with. I argue that the space-time clustering of cases from a starting epidemic is due to a sudden and high increase of the contact rate beyond a threshold. Interaction rather than main effects and nonlinear rather than linear dynamics are involved. Second, the incubation period of disease is studied. I advocate that an individual-level deterministic process underlies Sartwell's model of the incubation period. This accounts for the robustness of the model vis-à-vis confounding variables. Third, monozygotic twinning is analyzed. Assumed by some to be a random process, monozygotic twinning proves to be dynamically different from dizygotic or single-maternity processes; its dynamics can actually be chaotic. Throughout the provided examples, the point is made that chancelike phenomena are primarily concerned with chaos theory. For biological problems showing recurrent inconsistencies by stochastic modeling, dynamic modeling should be envisaged. Inconsistencies can suggest that the relevant factors are out of the model and that they are related deterministically. Finally, spectral analysis and attractors in the phase space are presented; these tools can aid the population biologist in tracing out chaos from

  2. Differences in Curriculum Structure between High School and University Biology: The Implications for Epistemological Access

    ERIC Educational Resources Information Center

    Kelly-Laubscher, Roisin F.; Luckett, Kathy

    2016-01-01

    Despite doing well in biology at high school, some students struggle with the same subject at university level. This can have implications for epistemological access--access to knowledge that allows students to remain at university. Therefore, it is important to identify factors that may be causing this problem. We propose that one such factor may…

  3. The (Biological or Cultural) Essence of Essentialism: Implications for Policy Support among Dominant and Subordinated Groups

    PubMed Central

    Soylu Yalcinkaya, Nur; Estrada-Villalta, Sara; Adams, Glenn

    2017-01-01

    Most research links (racial) essentialism to negative intergroup outcomes. We propose that this conclusion reflects both a narrow conceptual focus on biological/genetic essence and a narrow research focus from the perspective of racially dominant groups. We distinguished between beliefs in biological and cultural essences, and we investigated the implications of this distinction for support of social justice policies (e.g., affirmative action) among people with dominant (White) and subordinated (e.g., Black, Latino) racial identities in the United States. Whereas, endorsement of biological essentialism may have similarly negative implications for social justice policies across racial categories, we investigated the hypothesis that endorsement of cultural essentialism would have different implications across racial categories. In Studies 1a and 1b, we assessed the properties of a cultural essentialism measure we developed using two samples with different racial/ethnic compositions. In Study 2, we collected data from 170 participants using an online questionnaire to test the implications of essentialist beliefs for policy support. Consistent with previous research, we found that belief in biological essentialism was negatively related to policy support for participants from both dominant and subordinated categories. In contrast, the relationship between cultural essentialism and policy support varied across identity categories in the hypothesized way: negative for participants from the dominant category but positive for participants from subordinated categories. Results suggest that cultural essentialism may provide a way of identification that subordinated communities use to mobilize support for social justice. PMID:28611723

  4. The (Biological or Cultural) Essence of Essentialism: Implications for Policy Support among Dominant and Subordinated Groups.

    PubMed

    Soylu Yalcinkaya, Nur; Estrada-Villalta, Sara; Adams, Glenn

    2017-01-01

    Most research links (racial) essentialism to negative intergroup outcomes. We propose that this conclusion reflects both a narrow conceptual focus on biological/genetic essence and a narrow research focus from the perspective of racially dominant groups. We distinguished between beliefs in biological and cultural essences, and we investigated the implications of this distinction for support of social justice policies (e.g., affirmative action) among people with dominant (White) and subordinated (e.g., Black, Latino) racial identities in the United States. Whereas, endorsement of biological essentialism may have similarly negative implications for social justice policies across racial categories, we investigated the hypothesis that endorsement of cultural essentialism would have different implications across racial categories. In Studies 1a and 1b, we assessed the properties of a cultural essentialism measure we developed using two samples with different racial/ethnic compositions. In Study 2, we collected data from 170 participants using an online questionnaire to test the implications of essentialist beliefs for policy support. Consistent with previous research, we found that belief in biological essentialism was negatively related to policy support for participants from both dominant and subordinated categories. In contrast, the relationship between cultural essentialism and policy support varied across identity categories in the hypothesized way: negative for participants from the dominant category but positive for participants from subordinated categories. Results suggest that cultural essentialism may provide a way of identification that subordinated communities use to mobilize support for social justice.

  5. An outbreak of chickenpox in a military field hospital--the implications for biological warfare.

    PubMed Central

    Hepburn, N C; Brooks, T J

    1991-01-01

    An outbreak of chickenpox with spread to patients and staff on the isolation ward of a British field hospital during the Gulf war is described. The implications for the design and operation of field hospital isolation units should transmissible biological warfare agents be encountered in any future conflict are discussed. PMID:1774746

  6. The chemical biology of naphthoquinones and its environmental implications.

    PubMed

    Kumagai, Yoshito; Shinkai, Yasuhiro; Miura, Takashi; Cho, Arthur K

    2012-01-01

    Quinones are a group of highly reactive organic chemical species that interact with biological systems to promote inflammatory, anti-inflammatory, and anticancer actions and to induce toxicities. This review describes the chemistry, biochemistry, and cellular effects of 1,2- and 1,4-naphthoquinones and their derivatives. The naphthoquinones are of particular interest because of their prevalence as natural products and as environmental chemicals, present in the atmosphere as products of fuel and tobacco combustion. 1,2- and 1,4-naphthoquinones are also toxic metabolites of naphthalene, the major polynuclear aromatic hydrocarbon present in ambient air. Quinones exert their actions through two reactions: as prooxidants, reducing oxygen to reactive oxygen species; and as electrophiles, forming covalent bonds with tissue nucleophiles. The targets for these reactions include regulatory proteins such as protein tyrosine phosphatases; Kelch-like ECH-associated protein 1, the regulatory protein for NF-E2-related factor 2; and the glycolysis enzyme glyceraldehyde-3-phosphate dehydrogenase. Through their actions on regulatory proteins, quinones affect various cell signaling pathways that promote and protect against inflammatory responses and cell damage. These actions vary with the specific quinone and its concentration. Effects of exposure to naphthoquinones as environmental chemicals can vary with the physical state, i.e., whether the quinone is particle bound or is in the vapor state. The exacerbation of pulmonary diseases by air pollutants can, in part, be attributed to quinone action.

  7. Double hit lymphoma: from biology to therapeutic implications.

    PubMed

    Burotto, Mauricio; Berkovits, Alejandro; Dunleavy, Kieron

    2016-07-01

    Diffuse large B-cell lymphoma (DLBCL) is a molecularly heterogeneous disease defined by different cellular origins and mechanisms of oncogenic activation. Approximately 10% of DLBCL cases harbor a MYC rearrangement and this has been associated with a more aggressive clinical course following standard therapy. So-called 'double-hit lymphomas' (DHL) or 'triple hit lymphomas' (THL) occur when MYC is concurrently rearranged with BCL2 and/or BCL6. These tumors are characterized by high proliferation rate and a very poor outcome following standard R-CHOP (rituximab, cyclophosphamide, doxorubicin vincristine and prednisone) therapy, in most (though not all) studies that have looked at this. Though there is a paucity of published experience with other chemotherapy regimens, there is emerging evidence that more intensive approaches may improve outcome. Recently, there has been a lot of focus in the literature on 'double-expresser lymphomas' (DEL) with high MYC, BCL2 and/or BCL6 expression but typically without rearrangements of these genes. These DEL cases, have a poor outcome with R-CHOP and there is little consensus on how they should be approached. Expert commentary: This review will focus on the biology and treatment of DHL and DEL, discuss the outcome of these diseases with current standard as well as promising new approaches and conclude with a section on novel agents that are in development for these diseases.

  8. Triactome: Neuro–Immune–Adipose Interactions. Implication in Vascular Biology

    PubMed Central

    Chaldakov, George Nikov; Fiore, Marco; Ghenev, Peter I.; Beltowski, Jerzy; Ranćić, Gorana; Tunçel, Neşe; Aloe, Luigi

    2014-01-01

    Understanding how the precise interactions of nerves, immune cells, and adipose tissue account for cardiovascular and metabolic biology is a central aim of biomedical research at present. A long standing paradigm holds that the vascular wall is composed of three concentric tissue coats (tunicae): intima, media, and adventitia. However, large- and medium-sized arteries, where usually atherosclerotic lesions develop, are consistently surrounded by periadventitial adipose tissue (PAAT), we recently designated tunica adiposa (in brief, adiposa like intima, media, and adventitia). Today, atherosclerosis is considered an immune-mediated inflammatory disease featured by endothelial dysfunction/intimal thickening, medial atrophy, and adventitial lesions associated with adipose dysfunction, whereas hypertension is characterized by hyperinnervation-associated medial thickening due to smooth muscle cell hypertrophy/hyperplasia. PAAT expansion is associated with increased infiltration of immune cells, both adipocytes and immunocytes secreting pro-inflammatory and anti-inflammatory (metabotrophic) signaling proteins collectively dubbed adipokines. However, the role of vascular nerves and their interactions with immune cells and paracrine adipose tissue is not yet evaluated in such an integrated way. The present review attempts to briefly highlight the findings in basic and translational sciences in this area focusing on neuro–immune–adipose interactions, herein referred to as triactome. Triactome-targeted pharmacology may provide a novel therapeutic approach in cardiovascular disease. PMID:24782857

  9. Advances in Campylobacter biology and implications for biotechnological applications

    PubMed Central

    Jeon, Byeonghwa; Muraoka, Wayne T.; Zhang, Qijing

    2010-01-01

    Summary Campylobacter jejuni is a major foodborne pathogen of animal origin and a leading cause of bacterial gastroenteritis in humans. During the past decade, especially since the publication of the first C. jejuni genome sequence, major advances have been made in understanding the pathobiology and physiology of this organism. It is apparent that C. jejuni utilizes sophisticated mechanisms for effective colonization of the intestinal tracts in various animal species. Although Campylobacter is fragile in the environment and requires fastidious growth conditions, it exhibits great flexibility in the adaptation to various habitats including the gastrointestinal tract. This high adaptability is attributable to its genetically, metabolically and phenotypically diverse population structure and its ability to change in response to various challenges. Unlike other enteric pathogens, such as Escherichia coli and Salmonella, Campylobacter is unable to utilize exogenous glucose and mainly depends on the catabolism of amino acids as a carbon source. Campylobacter proves highly mutable in response to antibiotic treatments and possesses eukaryote‐like dual protein glycosylation systems, which modify flagella and other surface proteins with specific sugar structures. In this review we will summarize the distinct biological traits of Campylobacter and discuss the potential biotechnological approaches that can be developed to control this enteric pathogen. PMID:21255325

  10. Implications of Plasmodium vivax Biology for Control, Elimination, and Research

    PubMed Central

    Olliaro, Piero L.; Barnwell, John W.; Barry, Alyssa; Mendis, Kamini; Mueller, Ivo; Reeder, John C.; Shanks, G. Dennis; Snounou, Georges; Wongsrichanalai, Chansuda

    2016-01-01

    This paper summarizes our current understanding of the biology of Plasmodium vivax, how it differs from Plasmodium falciparum, and how these differences explain the need for P. vivax-tailored interventions. The article further pinpoints knowledge gaps where investments in research are needed to help identify and develop such specific interventions. The principal obstacles to reduce and eventually eliminate P. vivax reside in 1) its higher vectorial capacity compared with P. falciparum due to its ability to develop at lower temperature and over a shorter sporogonic cycle in the vector, allowing transmission in temperate zones and making it less sensitive to vector control measures that are otherwise effective on P. falciparum; 2) the presence of dormant liver forms (hypnozoites), sustaining multiple relapsing episodes from a single infectious bite that cannot be diagnosed and are not susceptible to any available antimalarial except primaquine, with routine deployment restricted by toxicity; 3) low parasite densities, which are difficult to detect with current diagnostics leading to missed diagnoses and delayed treatments (and protracted transmission), coupled with 4) transmission stages (gametocytes) occurring early in acute infections, before infection is diagnosed. PMID:27799636

  11. Mars Sample Return and Flight Test of a Small Bimodal Nuclear Rocket and ISRU Plant

    NASA Technical Reports Server (NTRS)

    George, Jeffrey A.; Wolinsky, Jason J.; Bilyeu, Michael B.; Scott, John H.

    2014-01-01

    A combined Nuclear Thermal Rocket (NTR) flight test and Mars Sample Return mission (MSR) is explored as a means of "jump-starting" NTR development. Development of a small-scale engine with relevant fuel and performance could more affordably and quickly "pathfind" the way to larger scale engines. A flight test with subsequent inflight postirradiation evaluation may also be more affordable and expedient compared to ground testing and associated facilities and approvals. Mission trades and a reference scenario based upon a single expendable launch vehicle (ELV) are discussed. A novel "single stack" spacecraft/lander/ascent vehicle concept is described configured around a "top-mounted" downward firing NTR, reusable common tank, and "bottom-mount" bus, payload and landing gear. Requirements for a hypothetical NTR engine are described that would be capable of direct thermal propulsion with either hydrogen or methane propellant, and modest electrical power generation during cruise and Mars surface insitu resource utilization (ISRU) propellant production.

  12. Performance of Adsorption - Based CO2 Acquisition Hardware for Mars ISRU

    NASA Technical Reports Server (NTRS)

    Finn, John E.; Mulloth, Lila M.; Borchers, Bruce A.; Luna, Bernadette (Technical Monitor)

    2000-01-01

    Chemical processing of the dusty, low-pressure Martian atmosphere typically requires conditioning and compression of the gases as first steps. A temperature-swing adsorption process can perform these tasks using nearly solid-state hardware and with relatively low power consumption compared to alternative processes. In addition, the process can separate the atmospheric constituents, producing both pressurized CO2 and a buffer gas mixture of nitrogen and argon. To date we have developed and tested adsorption compressors at scales appropriate for the near-term robotic missions that will lead the way to ISRU-based human exploration missions. In this talk we describe the characteristics, testing, and performance of these devices. We also discuss scale-up issues associated with meeting the processing demands of sample return and human missions.

  13. Development and Testing of an ISRU Soil Mechanics Vacuum Test Facility

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie E.; Wilkinson, R. Allen

    2014-01-01

    For extraterrestrial missions, earth based testing in relevant environments is key to successful hardware development. This is true for both early component level development and system level integration. For In-Situ Resource Utilization (ISRU) on the moon, hardware must interface with the surface material, or regolith, in a vacuum environment. A relevant test environment will therefore involve a vacuum chamber with a controlled, properly conditioned bed of lunar regolith simulant. However, in earth-based granular media, such as lunar regolith simulant, gases trapped within the material pore structures and water adsorbed to all particle surfaces will release when exposed to vacuum. Early vacuum testing has shown that this gas release can occur violently, which loosens and weakens the simulant, altering the consolidation state. A mid-size chamber (3.66 m tall, 1.5 m inner diameter) at the NASA Glenn Research Center has been modified to create a soil mechanics test facility. A 0.64 m deep by 0.914 m square metric ton bed of lunar simulant was placed under vacuum using a variety of pumping techniques. Both GRC-3 and LHT-3M simulant types were used. Data obtained from an electric cone penetrometer can be used to determine strength properties at vacuum including: cohesion, friction angle, bulk density and shear modulus. Simulant disruptions, caused by off-gassing, affected the strength properties, but could be mitigated by reducing pump rate. No disruptions were observed at pressures below 2.5 Torr, regardless of the pump rate. The slow off-gassing of the soil at low pressure lead to long test times; a full week to reach 10(exp -5) Torr. Robotic soil manipulation would enable multiple ISRU hardware test within the same vacuum cycle. The feasibility of a robotically controlled auger and tamper was explored at vacuum conditions.

  14. Field Testing of a Pneumatic Regolith Feed System During a 2010 ISRU Field Campaign on Mauna Kea, Hawaii

    NASA Technical Reports Server (NTRS)

    Craft, Jack; Zacny, Kris; Chu, Philip; Wilson, Jack; Santoro, Chris; Carlson, Lee; Maksymuk, Michael; Townsend, Ivan I.; Mueller, Robert P.; Mantovani, James G.

    2010-01-01

    Lunar In Situ Resource Utilization (ISRU) consists of a number of tasks starting with mining of lunar regolith, followed by the transfer of regolith to an oxygen extraction reactor and finally processing the regolith and storing of extracted oxygen. The transfer of regolith from the regolith hopper at the ground level to an oxygen extraction reactor many feet above the surface could be accomplished in different ways, including using a mechanical auger, bucket ladder system or a pneumatic system. The latter system is commonly used on earth when moving granular materials since it offers high reliability and simplicity of operation. In this paper, we describe a pneumatic regolith feed system, delivering feedstock to a Carbothermal reactor and lessons learned from deploying the system during the 2010 ISRU field campaign on the Mauna Kea, Hawaii.

  15. RNA interference in Entamoeba histolytica: implications for parasite biology and gene silencing

    PubMed Central

    Zhang, Hanbang; Pompey, Justine M; Singh, Upinder

    2011-01-01

    Entamoeba histolytica is a major health threat to people in developing countries, where it causes invasive diarrhea and liver abscesses. The study of this important human pathogen has been hindered by a lack of tools for genetic manipulation. Recently, a number of genetic approaches based on variations of the RNAi method have been successfully developed and cloning of endogenous small-interfering RNAs from E. histolytica revealed an abundant population of small RNAs with an unusual 5′-polyphosphate structure. However, little is known about the implications of these findings to amebic biology or the mechanisms of gene silencing in this organism. In this article we review the literature relevant to RNAi in E. histolytica, discuss its implications for advances in gene silencing in this organism and outline potential future directions towards understanding the repertoire of RNAi and its impact on the biology of this deep-branching eukaryotic parasite. PMID:21162639

  16. Posttranslational modifications of desmin and their implication in biological processes and pathologies.

    PubMed

    Winter, Daniel L; Paulin, Denise; Mericskay, Mathias; Li, Zhenlin

    2014-01-01

    Desmin, the muscle-specific intermediate filament, is involved in myofibrillar myopathies, dilated cardiomyopathy and muscle wasting. Desmin is the target of posttranslational modifications (PTMs) such as phosphorylation, ADP-ribosylation and ubiquitylation as well as nonenzymatic modifications such as glycation, oxidation and nitration. Several PTM target residues and their corresponding modifying enzymes have been discovered in human and nonhuman desmin. The major effect of phosphorylation and ADP-ribosylation is the disassembly of desmin filaments, while ubiquitylation of desmin leads to its degradation. The regulation of the desmin filament network by phosphorylation and ADP-ribosylation was found to be implicated in several major biological processes such as myogenesis, myoblast fusion, muscle contraction, muscle atrophy, cell division and possibly desmin interactions with its binding partners. Phosphorylation of desmin is also implicated in many forms of desmin-related myopathies (desminopathies). In this review, we summarize the findings on desmin PTMs and their implication in biological processes and pathologies, and discuss the current knowledge on the regulation of the desmin network by PTMs. We conclude that the desmin filament network can be seen as an intricate scaffold for muscle cell structure and biological processes and that its dynamics can be affected by PTMs. There are now precise tools to investigate PTMs and visualize cellular structures that have been underexploited in the study of desminopathies. Future studies should focus on these aspects.

  17. ISRU Reactant, Fuel Cell Based Power Plant for Robotic and Human Mobile Exploration Applications

    NASA Astrophysics Data System (ADS)

    Baird, Russell S.; Sanders, Gerald; Simon, Thomas; McCurdy, Kerri

    2003-01-01

    Three basic power generation system concepts are generally considered for lander, rover, and Extra-Vehicular Activity (EVA) assistant applications for robotic and human Moon and Mars exploration missions. The most common power system considered is the solar array and battery system. While relatively simple and successful, solar array/battery systems have some serious limitations for mobile applications. For typical rover applications, these limitations include relatively low total energy storage capabilities, daylight only operating times (6 to 8 hours on Mars), relatively short operating lives depending on the operating environment, and rover/lander size and surface use constraints. Radioisotope power systems are being reconsidered for long-range science missions. Unfortunately, the high cost, political controversy, and launch difficulties that are associated with nuclear-based power systems suggests that the use of radioisotope powered landers, rovers, and EVA assistants will be limited. The third power system concept now being considered are fuel cell based systems. Fuel cell power systems overcome many of the performance and surface exploration limitations of solar array/battery power systems and the prohibitive cost and other difficulties associated with nuclear power systems for mobile applications. In an effort to better understand the capabilities and limitations of fuel cell power systems for Moon and Mars exploration applications. NASA is investigating the use of In-Situ Resource Utilization (ISRU) produced reactant, fuel cell based power plants to power robotic outpost rovers, science equipment, and future human spacecraft, surface-excursion rovers, and EVA assistant rovers. This paper will briefly compare the capabilities and limitations of fuel cell power systems relative to solar array/battery and nuclear systems, discuss the unique and enhanced missions that fuel cell power systems enable, and discuss the common technology and system attributes

  18. ISRU Reactant, Fuel Cell Based Power Plant for Robotic and Human Mobile Exploration Applications

    NASA Technical Reports Server (NTRS)

    Baird, Russell S.; Sanders, Gerald; Simon, Thomas; McCurdy, Kerri

    2003-01-01

    Three basic power generation system concepts are generally considered for lander, rover, and Extra-Vehicular Activity (EVA) assistant applications for robotic and human Moon and Mars exploration missions. The most common power system considered is the solar array and battery system. While relatively simple and successful, solar array/battery systems have some serious limitations for mobile applications. For typical rover applications, these limitations include relatively low total energy storage capabilities, daylight only operating times (6 to 8 hours on Mars), relatively short operating lives depending on the operating environment, and rover/lander size and surface use constraints. Radioisotope power systems are being reconsidered for long-range science missions. Unfortunately, the high cost, political controversy, and launch difficulties that are associated with nuclear-based power systems suggests that the use of radioisotope powered landers, rovers, and EVA assistants will be limited. The third power system concept now being considered are fuel cell based systems. Fuel cell power systems overcome many of the performance and surface exploration limitations of solar array/battery power systems and the prohibitive cost and other difficulties associated with nuclear power systems for mobile applications. In an effort to better understand the capabilities and limitations of fuel cell power systems for Moon and Mars exploration applications, NASA is investigating the use of in-Situ Resource Utilization (ISRU) produced reactant, fuel cell based power plants to power robotic outpost rovers, science equipment, and future human spacecraft, surface-excursion rovers, and EVA assistant rovers. This paper will briefly compare the capabilities and limitations of fuel cell power systems relative to solar array/battery and nuclear systems, discuss the unique and enhanced missions that fuel cell power systems enable, and discuss the common technology and system attributes

  19. Separation of Carbon Monoxide and Carbon Dioxide for Mars ISRU-Concepts

    NASA Technical Reports Server (NTRS)

    LeVan, M. Douglas; Finn, John E.; Sridhar, K. R.

    2000-01-01

    Solid oxide electrolyzers, such as electrolysis cells utilizing yttria-stabilized zirconia, can produce oxygen from Mars atmospheric carbon dioxide and reject carbon monoxide and unreacted carbon dioxide in a separate stream. The oxygen-production process has been shown to be far more efficient if the high-pressure, unreacted carbon dioxide can be separated and recycled back into the feed stream. Additionally, the mass of the adsorption compressor can be reduced. Also, the carbon monoxide by-product is a valuable fuel for space exploration and habitation, with applications from fuel cells to production of hydrocarbons and plastics. In our research, we will design, construct, and test an innovative, robust, low mass, low power separation device that can recover carbon dioxide and carbon monoxide for Mars ISRU. Such fundamental process technology, involving gas-solid phase separation in a reduced gravitational environment, will help to enable Human Exploration and Development of Space. The separation device will be scaled to operate with a CO2 sorption compressor and a zirconia electrolysis device built at the NASA Ames Research Center and the University of Arizona, respectively. In our research, we will design, construct, and test an innovative, robust, low mass, low power separation device that can recover carbon dioxide and carbon monoxide for Mars ISRU, Such fundamental process technology, involving gas-solid phase separation in a reduced gravitational environment, will help to enable Human Exploration and Development of Space. The separation device will be scaled to operate with a CO2 sorption compressor and a zirconia electrolysis device built at the NASA Ames Research Center and the University of Arizona, The separation device will be scaled to operate with a CO2 sorption compressor and a zirconia electrolysis device built at the NASA Ames Research Center and the University of Arizona, Research needs for the design shown are as follows: (1) The best adsorbent

  20. The formal nature of emergent biological organization and its implications for understandings of closure.

    PubMed

    Sheets-Johnstone, M

    2000-01-01

    This paper shows how recognition of biological form, of which the dynamics of closure is an integral part, is mandated by research on autopoietic systems, self-organization, evolutionary theory, and on topics in a variety of other areas, including infant and child development. It shows how a "matter pure and simple" (a mechanical concept of nature) is inimical to veridical understandings and explanations of emergent organization from the level of cells to the level of intact organisms--animate forms. By means of an analysis and discussion of writings by prominent researchers in diverse fields, a brief inquiry into neuron firing, and a consideration of intrinsic dynamics and primal animation, this paper shows that a principle of motion or animation informs biological nature. In other words, the fundamentally dynamic character of biological form at all levels exemplifies the kinetic character of living matter. The final section of this paper pinpoints implications for closure, emphasizing the need for an acknowledgement of the dynamics of closure and the need for theoretical and biological reformulations of living systems that incorporate that dynamics. It exemplifies the implication in each instance with reference to authors represented in this volume.

  1. Causal attributions of obese men and women in genetic testing: implications of genetic/biological attributions.

    PubMed

    Hilbert, Anja; Dierk, Jan-Michael; Conradt, Matthias; Schlumberger, Pia; Hinney, Anke; Hebebrand, Johannes; Rief, Winfried

    2009-09-01

    The present study sought to investigate genetic/biological attributions of obesity, their associations with a predisposition to obesity and their crossectional and longitudinal implications for weight regulation in obese individuals presenting for genetic testing and counselling. A total of 421 obese men and women underwent psychological and anthropometric assessment and a mutation screen of the melanocortin-4 receptor gene. At study entry, women revealed more genetic/biological attributions than men on the Revised Illness Perception Questionnaire adapted to obesity (86.2% versus 59.7%). Genetic/biological attributions of obesity were associated in both sexes with a family history of obesity, assessed through Stunkard's Figure Rating Scale. In both sexes, genetic/biological attributions were unrelated to weight regulation beliefs and behaviour (i.e. self-efficacy, controllability beliefs, restrained eating and physical activity), assessed through standardised questionnaires or interview at baseline and at six-month follow-up. In addition, causal attributions and weight regulation beliefs and behaviour were not predictive of body mass index at six-month follow-up. Overall, the results indicate that causal attributions of obesity to genetic/biological factors in obese individuals presenting for genetic screening and counselling are crossectionally and longitudinally unrelated to weight regulation and longer-term weight outcome. Those who attribute their obesity to genetic/biological factors likely have a familial obesity risk.

  2. A Re-examination of the Fine Structure of the Living Cell and its Implications for Biological Education.

    ERIC Educational Resources Information Center

    Hillman, Harold; Sartory, Peter

    1980-01-01

    Presents a summary of evidence suggesting that certain cellular parts may be artifacts arising during preparation of tissues for electron microscopy and discusses implications of same for biology curriculum and instruction. (SK)

  3. Preparation of a Frozen Regolith Simulant Bed for ISRU Component Testing in a Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Klenhenz, Julie; Linne, Diane

    2013-01-01

    In-Situ Resource Utilization (ISRU) systems and components have undergone extensive laboratory and field tests to expose hardware to relevant soil environments. The next step is to combine these soil environments with relevant pressure and temperature conditions. Previous testing has demonstrated how to incorporate large bins of unconsolidated lunar regolith into sufficiently sized vacuum chambers. In order to create appropriate depth dependent soil characteristics that are needed to test drilling operations for the lunar surface, the regolith simulant bed must by properly compacted and frozen. While small cryogenic simulant beds have been created for laboratory tests, this scale effort will allow testing of a full 1m drill which has been developed for a potential lunar prospector mission. Compacted bulk densities were measured at various moisture contents for GRC-3 and Chenobi regolith simulants. Vibrational compaction methods were compared with the previously used hammer compaction, or "Proctor", method. All testing was done per ASTM standard methods. A full 6.13 m3 simulant bed with 6 percent moisture by weight was prepared, compacted in layers, and frozen in a commercial freezer. Temperature and desiccation data was collected to determine logistics for preparation and transport of the simulant bed for thermal vacuum testing. Once in the vacuum facility, the simulant bed will be cryogenically frozen with liquid nitrogen. These cryogenic vacuum tests are underway, but results will not be included in this manuscript.

  4. Multirobot Lunar Excavation and ISRU Using Artificial-Neural-Tissue Controllers

    SciTech Connect

    Thangavelautham, Jekanthan; Smith, Alexander; Abu El Samid, Nader; Ho, Alexander; D'Eleuterio, Gabriele M. T.; Boucher, Dale; Richard, Jim

    2008-01-21

    Automation of site preparation and resource utilization on the Moon with teams of autonomous robots holds considerable promise for establishing a lunar base. Such multirobot autonomous systems would require limited human support infrastructure, complement necessary manned operations and reduce overall mission risk. We present an Artificial Neural Tissue (ANT) architecture as a control system for autonomous multirobot excavation tasks. An ANT approach requires much less human supervision and pre-programmed human expertise than previous techniques. Only a single global fitness function and a set of allowable basis behaviors need be specified. An evolutionary (Darwinian) selection process is used to 'breed' controllers for the task at hand in simulation and the fittest controllers are transferred onto hardware for further validation and testing. ANT facilitates 'machine creativity', with the emergence of novel functionality through a process of self-organized task decomposition of mission goals. ANT based controllers are shown to exhibit self-organization, employ stigmergy (communication mediated through the environment) and make use of templates (unlabeled environmental cues). With lunar in-situ resource utilization (ISRU) efforts in mind, ANT controllers have been tested on a multirobot excavation task in which teams of robots with no explicit supervision can successfully avoid obstacles, interpret excavation blueprints, perform layered digging, avoid burying or trapping other robots and clear/maintain digging routes.

  5. Multirobot Lunar Excavation and ISRU Using Artificial-Neural-Tissue Controllers

    NASA Astrophysics Data System (ADS)

    Thangavelautham, Jekanthan; Smith, Alexander; Abu El Samid, Nader; Ho, Alexander; Boucher, Dale; Richard, Jim; D'Eleuterio, Gabriele M. T.

    2008-01-01

    Automation of site preparation and resource utilization on the Moon with teams of autonomous robots holds considerable promise for establishing a lunar base. Such multirobot autonomous systems would require limited human support infrastructure, complement necessary manned operations and reduce overall mission risk. We present an Artificial Neural Tissue (ANT) architecture as a control system for autonomous multirobot excavation tasks. An ANT approach requires much less human supervision and pre-programmed human expertise than previous techniques. Only a single global fitness function and a set of allowable basis behaviors need be specified. An evolutionary (Darwinian) selection process is used to `breed' controllers for the task at hand in simulation and the fittest controllers are transferred onto hardware for further validation and testing. ANT facilitates `machine creativity', with the emergence of novel functionality through a process of self-organized task decomposition of mission goals. ANT based controllers are shown to exhibit self-organization, employ stigmergy (communication mediated through the environment) and make use of templates (unlabeled environmental cues). With lunar in-situ resource utilization (ISRU) efforts in mind, ANT controllers have been tested on a multirobot excavation task in which teams of robots with no explicit supervision can successfully avoid obstacles, interpret excavation blueprints, perform layered digging, avoid burying or trapping other robots and clear/maintain digging routes.

  6. Human Lunar Mission Capabilities Using SSTO, ISRU and LOX-Augmented NTR Technologies: A Preliminary Assessment

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.

    1995-01-01

    The feasibility of conducting human missions to the Moon is examined assuming the use of three 'high leverage' technologies: (1) a single-stage-to-orbit (SSTO) launch vehicle, (2) 'in-situ' resource utilization (ISRU)--specifically 'lunar-derived' liquid oxygen (LUNOX), and (3) LOX-augmented nuclear thermal rocket (LANTR) propulsion. Lunar transportation system elements consisting of a LANTR-powered lunar transfer vehicle (LTV) and a chemical propulsion lunar landing/Earth return vehicle (LERV) are configured to fit within the 'compact' dimensions of the SSTO cargo bay (diameter: 4.6 m/length: 9.0 m) while satisfying an initial mass in low Earth orbit (IMLEO) limit of approximately 60 t (3 SSTO launches). Using approximately 8 t of LUNOX to 'reoxidize' the LERV for a 'direct return' flight to Earth reduces its size and mass allowing delivery to LEO on a single 20 t SSTO launch. Similarly, the LANTR engine's ability to operate at any oxygen/ hydrogen mixture ratio from 0 to 7 with high specific impulse (approximately 940 to 515 s) is exploited to reduce hydrogen tank volume, thereby improving packaging of the LANTR LTV's 'propulsion' and 'propellant modules'. Expendable and reusable, piloted and cargo missions and vehicle designs are presented along with estimates of LUNOX production required to support the different mission modes. Concluding remarks address the issue of lunar transportation system costs from the launch vehicle perspective.

  7. Photochemical source of biological substrates in sea water: implications for carbon cycling

    NASA Astrophysics Data System (ADS)

    Kieber, David J.; McDaniel, Julie; Mopper, Kenneth

    1989-10-01

    DISSOLVED organic carbon (DOC) in sea water represents one of the largest reservoirs of carbon on the earth1. The main fraction of this DOC is generally believed to be composed of old2, biologi-cally refractory material3 such as humic substances, for which the removal mechanisms remain largely unknown. One potentially important removal process in the ocean that has not been investi-gated is the photochemical breakdown of this DOC in the photic zone to form biologically labile organic products. Here we show that biological uptake of pyruvate is highly correlated to its rate of photochemical production in sea water (r = 0.964), and that the photochemical precursor(s) of pyruvate is from the fraction of DOC having a nominal molecular weight of 500. This is the first evidence that photochemical breakdown of high-molecular-weight marine DOC, which is presumably biologically refractory, results in the production of a compound that is used by plankton as a substrate. Our results have important implications for the oceanic carbon cycle, particularly with respect to planktonic-food-web dynamics and the global carbon budget.

  8. Log normal distribution of cellular uptake of radioactivity: implications for biologic responses to radiopharmaceuticals.

    PubMed

    Neti, Prasad V S V; Howell, Roger W

    2006-06-01

    It is widely recognized that radiopharmaceuticals are generally distributed nonuniformly in tissues. Such nonuniformities are observed over the entire range of spatial levels, ranging from organ to subcellular levels. The implications of nonuniform distributions of radioactivity for dosimetry, and ultimately for the biologic response of tissues containing radioactivity, have been investigated extensively. However, there is a paucity of experimental data on the distribution of cellular activity within a population of cells. In the present study, the distribution of activity per cell is experimentally determined and its implications for predicting biologic response are examined. Chinese hamster V79 cells were exposed to different concentrations of (210)Po-citrate. The radiolabeled cells were washed, seeded into culture dishes or glass slides, covered with photographic emulsion, and stored in an opaque container. Subsequently, the emulsion was developed, thereby resulting in observable alpha-particle tracks that were scored. The distribution of activity per cell was found to be well described by a log normal distribution function. Theoretic modeling of cell survival as a function of mean activity per cell showed that survival curves differed substantially when the activity per cell was log normally distributed versus when it was assumed conventionally that every cell in the population contained the mean activity. The present study provides experimental evidence of log normal cellular uptake of radioactivity. Theoretic calculations show that a log normal distribution of cellular activity can have a substantial impact on modeling the biologic response of cell populations.

  9. Understanding Schizophrenia as a Disorder of Consciousness: Biological Correlates and Translational Implications from Quantum Theory Perspectives

    PubMed Central

    Venkatasubramanian, Ganesan

    2015-01-01

    From neurophenomenological perspectives, schizophrenia has been conceptualized as “a disorder with heterogeneous manifestations that can be integrally understood to involve fundamental perturbations in consciousness”. While these theoretical constructs based on consciousness facilitate understanding the ‘gestalt’ of schizophrenia, systematic research to unravel translational implications of these models is warranted. To address this, one needs to begin with exploration of plausible biological underpinnings of “perturbed consciousness” in schizophrenia. In this context, an attractive proposition to understand the biology of consciousness is “the orchestrated object reduction (Orch-OR) theory” which invokes quantum processes in the microtubules of neurons. The Orch-OR model is particularly important for understanding schizophrenia especially due to the shared ‘scaffold’ of microtubules. The initial sections of this review focus on the compelling evidence to support the view that “schizophrenia is a disorder of consciousness” through critical summary of the studies that have demonstrated self-abnormalities, aberrant time perception as well as dysfunctional intentional binding in this disorder. Subsequently, these findings are linked with ‘Orch-OR theory’ through the research evidence for aberrant neural oscillations as well as microtubule abnormalities observed in schizophrenia. Further sections emphasize the applicability and translational implications of Orch-OR theory in the context of schizophrenia and elucidate the relevance of quantum biology to understand the origins of this puzzling disorder as “fundamental disturbances in consciousness”. PMID:25912536

  10. Understanding schizophrenia as a disorder of consciousness: biological correlates and translational implications from quantum theory perspectives.

    PubMed

    Venkatasubramanian, Ganesan

    2015-04-30

    From neurophenomenological perspectives, schizophrenia has been conceptualized as "a disorder with heterogeneous manifestations that can be integrally understood to involve fundamental perturbations in consciousness". While these theoretical constructs based on consciousness facilitate understanding the 'gestalt' of schizophrenia, systematic research to unravel translational implications of these models is warranted. To address this, one needs to begin with exploration of plausible biological underpinnings of "perturbed consciousness" in schizophrenia. In this context, an attractive proposition to understand the biology of consciousness is "the orchestrated object reduction (Orch-OR) theory" which invokes quantum processes in the microtubules of neurons. The Orch-OR model is particularly important for understanding schizophrenia especially due to the shared 'scaffold' of microtubules. The initial sections of this review focus on the compelling evidence to support the view that "schizophrenia is a disorder of consciousness" through critical summary of the studies that have demonstrated self-abnormalities, aberrant time perception as well as dysfunctional intentional binding in this disorder. Subsequently, these findings are linked with 'Orch-OR theory' through the research evidence for aberrant neural oscillations as well as microtubule abnormalities observed in schizophrenia. Further sections emphasize the applicability and translational implications of Orch-OR theory in the context of schizophrenia and elucidate the relevance of quantum biology to understand the origins of this puzzling disorder as "fundamental disturbances in consciousness".

  11. Molecular biology in marine science: Scientific questions, technological approaches, and practical implications

    SciTech Connect

    1994-12-31

    The ocean plays an important role in regulating the earth`s climate, sustains a large portion of the earth`s biodiversity, is a tremendous reservoir of commercially important substances, and is used for a variety of often conflicting purposes. In recent decades marine scientists have discovered much about the ocean and its organisms, yet many important fundamental questions remain unanswered. Human populations have increased, particularly in coastal regions. As a result, the marine environment in these areas is increasingly disrupted by human activities, including pollution and the depletion of some ecologically and commercially important species. There is a sense of urgency about reducing human impacts on the ocean and a need to understand how altered ecosystems and the loss of marine species and biodiversity could affect society. During the past two decades, the development of sophisticated technologies and instruments for biomedical research has resulted in significant advances in the biological sciences. While some of these technologies have been readily incorporated into the study of marine organisms as models for understanding basic biology, the value of molecular techniques for addressing problems in marine biology and biological oceanography has only recently begun to be appreciated. This report defines critical scientific questions in marine biology and biological oceanography, describes the molecular technologies that could be used to answer these questions, and discusses some of the implications and economic opportunities that might result from this research which could potentially improve the international competitive position of the United States in the rapidly growing area of marine biotechnology. The committee recommends that the federal government provide the infrastructure necessary to use the techniques of molecular biology in the marine sciences.

  12. The pediatric sepsis biomarker risk model: potential implications for sepsis therapy and biology

    PubMed Central

    Alder, Matthew N; Lindsell, Christopher J; Wong, Hector R

    2015-01-01

    Sepsis remains a major cause of morbidity and mortality in adult and pediatric intensive care units. Heterogeneity of demographics, comorbidities, biological mechanisms, and severity of illness leads to difficulty in determining which patients are at highest risk of mortality. Determining mortality risk is important for weighing the potential benefits of more aggressive interventions and for deciding whom to enroll in clinical trials. Biomarkers can be used to parse patients into different risk categories and can outperform current methods of patient risk stratification based on physiologic parameters. Here we review the Pediatric Sepsis Biomarker Risk Model that has also been modified and applied to estimate mortality risk in adult patients. We compare the two models and speculate on the biological implications of the biomarkers in patients with sepsis. PMID:24754535

  13. Recent biologic and genetic advances in neuroblastoma: Implications for diagnostic, risk stratification, and treatment strategies.

    PubMed

    Newman, Erika A; Nuchtern, Jed G

    2016-10-01

    Neuroblastoma is an embryonic cancer of neural crest cell lineage, accounting for up to 10% of all pediatric cancer. The clinical course is heterogeneous ranging from spontaneous regression in neonates to life-threatening metastatic disease in older children. Much of this clinical variance is thought to result from distinct pathologic characteristics that predict patient outcomes. Consequently, many research efforts have been focused on identifying the underlying biologic and genetic features of neuroblastoma tumors in order to more clearly define prognostic subgroups for treatment stratification. Recent technological advances have placed emphasis on the integration of genetic alterations and predictive biologic variables into targeted treatment approaches to improve patient survival outcomes. This review will focus on these recent advances and the implications they have on the diagnostic, staging, and treatment approaches in modern neuroblastoma clinical management.

  14. Biologic implications of extracellular adenosine in hepatic ischemia and reperfusion injury

    PubMed Central

    Zimmerman, Michael A.; Kam, Igal; Eltzschig, Holger; Grenz, Almut

    2013-01-01

    The purine nucleoside adenosine is clinically employed in the treatment of supraventricular tachycardia. In addition, it has direct coronary vasodilatory effects, and may influence platelet aggregation. Experimental observations mechanistically link extracellular adenosine to cellular adaptation to hypoxia. Adenosine generation has been implicated in several pathophysiologic processes including angiogenesis, tumor defenses, and neurodegeneration. In solid organ transplantation, prolonged tissue ischemia and subsequent reperfusion injury may lead to profound graft dysfunction. Importantly, conditions of limited oxygen availability are associated with increased production of extracellular adenosine and subsequent tissue protection. Within the rapidly expanding field of adenosine biology, several enzymatic steps in adenosine production have been characterized and multiple receptor subtypes have been identified. In this review, we briefly examine the biologic steps involved in adenosine generation, and chronicle the current state of adenosine signaling in hepatic ischemia and reperfusion injury. PMID:23924168

  15. Environmental and biological applications and implications of soft and condensed nanomaterials

    NASA Astrophysics Data System (ADS)

    Chen, Pengyu

    Recent innovations and growth of nanotechnology have spurred exciting technological and commercial developments of nanomaterails. Their appealing physical and physicochemical properties offer great opportunities in biological and environmental applications, while in the meantime may compromise human health and environmental sustainability through either unintentional exposure or intentional discharge. Accordingly, this dissertation exploits the physicochemical behavior of soft dendritic polymers for environmental remediation and condensed nano ZnO tetrapods for biological sensing (Chapter two-four), and further delineate the environmental implications of such nanomaterials using algae- the major constituent of the aquatic food chain-as a model system (Chapter five). This dissertation is presented as follows. Chapter one presents a general review of the characteristic properties, applications, forces dictating nanomaterials, and their biological and environmental implications of the most produced and studied soft and condensed nanomaterials. In addition, dendritic polymers and ZnO nanomaterials are thoroughly reviewed separately. Chapter two investigates the physicochemical properties of poly(amidoamine)-tris(hydroxymethyl)amidomethane- dendrimer for its potential applications in water purification. The binding mechanisms and capacities of this dendrimer in hosting major environmental pollutants including cationic copper, anionic nitrate, and polyaromatic phenanthrene are discussed. Chapter three exploits a promising use of dendrimers for removal of potentially harmful discharged nanoparticles (NPs). Specifically, fullerenols are used as a model nanomaterial, and their interactions with two different generations of dendrimers are studied using spectrophotometry and thermodynamics methods. Chapter four elucidates two novel optical schemes for sensing environmental pollutants and biological compounds using dendrimer-gold nanowire complex and gold-coated ZnO tetrapods

  16. Dormant Circulating Tumor Cells in Prostate Cancer: Therapeutic, Clinical and Biological Implications.

    PubMed

    Alvarez-Cubero, Maria J; Vázquez-Alonso, Fernando; Puche-Sanz, Ignacio; Ortega, F Gabriel; Martin-Prieto, M; Garcia-Puche, José L; Pascual-Geler, Manrique; Lorente, José A; Cozar-Olmo, José M; Serrano, Maria J

    2016-01-01

    Circulating Tumor Cells (CTCs) are a valuable prognostic factor in several solid tumors. By understanding the biological characteristics of CTCs we could better understand the biology of metastasis. CTCs usually adopt a dormant state that is believed to be a strategy to survive in extreme conditions. To enter a dormant state, CTCs undergo numerous phenotypic, genetic and functional mutations that significantly affect the efficacy of the therapies used to kill dormant CTCs. Hence, understanding the biological events involved in the dormancy process of CTCs would allow the identification of new therapeutic targets. Some experimental studies or preclinical models have explored these biological events, as well as the molecular factors that contribute to the maintenance of and release from dormancy. However, few studies have assessed the effects of anticancer therapies on dormant cells. This study reviews current the data currently available on cell dormancy mechanisms in prostate cancer, with a special focus on the functional, genetic and phenotypic plasticity of CTCs and their potential implications in the clinical and therapeutic management of prostate cancer.

  17. Propositions of Schroedinger and Dyson: Implications for program development in secondary school biology

    NASA Astrophysics Data System (ADS)

    Kaiser-Antonowich, Roxanne

    The purpose of this study is to ascertain whether there is a linkage between the special case of New Jersey Core Curriculum Content Standards for Science as they represent biology, and the propositions of Schrodinger and Dyson. The aim of the study is to derive implications for program development in secondary school biology. Critical review reveals that the New Jersey Core Curriculum Content Standards for Science do not provide linkage to biology and the propositions of Erwin Schrodinger and Freeman Dyson. If life is characterized by replication and metabolism, then Schrodinger and Dyson present a plausible argument toward describing life as reciprocal forms and functions that characterize a living system. Examination revealed that Schrodinger, in stating that life can be characterized by the processes of replication and metabolism, emphasized replication and virtually ignored metabolism. Dyson also acknowledges the relationship of metabolism to replication. Examination of Dyson revealed that rather than describing metabolism as a characterization of life, he advances the origin of metabolism and its connection to the origin of life. If metabolism and replication characterize life and if the origin of life is within the domain of biology, then Schrodinger's and Dyson's propositions are central to the characterization of biology. If program development for secondary school biology requires accurate description of its domain, then it is necessary to acknowledge the complexity of life forms. There is as yet no universally accepted general description of life and no reasonable consensus for something to be termed living. If the conditions for something to be termed living are the capacity to reproduce self as maintained by Schrodinger, and the capacity for self-organization preserved through natural selection as proposed by Dyson, then these conditions form the basis for program development.

  18. Access and benefit sharing (ABS) under the convention on biological diversity (CBD): implications for microbial biological control

    USDA-ARS?s Scientific Manuscript database

    Researchers and implementers of biological control are confronted with a variety of scientific, regulatory and administrative challenges to their biological control programs. One developing challenge will arise from the implementation of provisions of the Convention on Biological Diversity (CBD) co...

  19. ISRU Soil Mechanics Vacuum Facility: Soil Bin Preparation and Simulant Strength Characterization

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie; Wilkinson, Allen

    2012-01-01

    Testing in relevant environments is key to exploration mission hardware development. This is true on both the component level (in early development) and system level (in late development stages). During ISRU missions the hardware will interface with the soil (digging, roving, etc) in a vacuum environment. A relevant test environment will therefore involve a vacuum chamber with a controlled, conditioned simulant bed. However, in earth-based granular media, such as lunar soil simulant, gases trapped within the material pore structures and water adsorbed to all particle surfaces will release when exposed to vacuum. Early vacuum testing has shown that this gas release can occur violently, which loosens and weakens the simulant, altering the consolidation state. The Vacuum Facility #13, a mid-size chamber (3.66m tall, 1.5m inner diameter) at the NASA Glenn Research Center has been modified to create a soil mechanics test facility. A 0.64m deep by 0.914m square metric ton bed of lunar simulant was placed under vacuum using a variety of pumping techniques. Both GRC-3 and LHT-3M simulant types have been used. An electric cone penetrometer was used to measure simulant strength properties at vacuum including: cohesion, friction angle, bulk density and shear modulus. Simulant disruptions, caused by off gassing, affected the strength properties, but could be mitigated by reducing pump rate. No disruptions were observed at pressures below 2.5Torr, regardless of the pump rate. However, slow off gassing of the soil lead to long test times, a full week, to reach 10-5Torr. This work highlights the need for robotic machine-simulant hardware and operations in vacuum to expeditiously perform (sub-)systems tests.

  20. The Mars Oxygen ISRU Experiment (MOXIE) on the yet-to-be-named Mars 2020 Lander

    NASA Astrophysics Data System (ADS)

    Hecht, M. H.; Hoffman, J.; Rapp, D.; Voecks, G.; Lackner, K. S.; Hartvigsen, J.; Yildiz, B.; Smith, P. H.; Pike, W. T.; Graves, C.; De La Torre Juarez, M.; Schreiner, S.; Madsen, M. B.

    2014-12-01

    A major challenge to sample return is the transport to Mars of an adequate supply of fuel and oxidizer (the heavier component) for the return trip. A possible novel architecture would be for the Mars Ascent Vehicle (MAV) to share a platform with a device that would manufacture the oxidizer in situ. Far from fanciful, that hypothetical platform would look very much like the Mars 2020 rover. The Mars Oxygen In Situ Resource Utilization (ISRU) Experiment, MOXIE, will produce 22 g/hr oxygen from atmospheric carbon dioxide using solid oxide electrolysis (SOXE). With proper refrigeration, it could readily fill a MAV tank with high Isp LOx while waiting for rendezvous with a sample acquisition rover. The immediate motivation for MOXIE, however, is as a prototype for a 100:1 scale unit that would serve the same function on an eventual human expedition. If optimistic plans for a crewed mission are realized, it may well carry the second, and far more bountiful, Mars sample return. To make 22 g/hr oxygen from the CO2 in the martian atmosphere, MOXIE must first collect and compress that CO2, while purging other atmospheric components (4-5 vol%) that would otherwise build up and choke the process. Two distinct technologies are under consideration for that function; a batch-process based on condensation by conventional cryocoolers, and an Advanced Technology Option mechanical compressor that would allow more efficient, continuous operation. The SOXE itself derives from solid oxide fuel cell (SOFC) technology, essentially running the fuel cell process in reverse by feeding in electricity and CO2 to produce O2and CO. MOXIE development is supported by the NASA HEOMD and STMD offices. We are particularly grateful to support from JPL and MIT, as well as our partners Ceramatec and Creare, in the preparation of the MOXIE proposal.

  1. Supporting cognition in systems biology analysis: findings on users' processes and design implications

    PubMed Central

    2009-01-01

    Background Current usability studies of bioinformatics tools suggest that tools for exploratory analysis support some tasks related to finding relationships of interest but not the deep causal insights necessary for formulating plausible and credible hypotheses. To better understand design requirements for gaining these causal insights in systems biology analyses a longitudinal field study of 15 biomedical researchers was conducted. Researchers interacted with the same protein-protein interaction tools to discover possible disease mechanisms for further experimentation. Results Findings reveal patterns in scientists' exploratory and explanatory analysis and reveal that tools positively supported a number of well-structured query and analysis tasks. But for several of scientists' more complex, higher order ways of knowing and reasoning the tools did not offer adequate support. Results show that for a better fit with scientists' cognition for exploratory analysis systems biology tools need to better match scientists' processes for validating, for making a transition from classification to model-based reasoning, and for engaging in causal mental modelling. Conclusion As the next great frontier in bioinformatics usability, tool designs for exploratory systems biology analysis need to move beyond the successes already achieved in supporting formulaic query and analysis tasks and now reduce current mismatches with several of scientists' higher order analytical practices. The implications of results for tool designs are discussed. PMID:19216777

  2. Long-Term Biological Monitoring of an Impaired Stream: Implications for Environmental Management [Special Issue

    SciTech Connect

    Adams, Marshall; Brandt, Craig C; Christensen, Sigurd W; Efroymson, Rebecca Ann; Greeley Jr, Mark Stephen; Ham, Kenneth; Kszos, Lynn A; Loar, James M; McCracken, Kitty; Morris, Gail Wright; Peterson, Mark J; Ryon, Michael G; Smith, John G; Southworth, George R; Stewart, Arthur J

    2011-01-01

    The long-term ecological recovery of an impaired stream in response to an industrial facility's pollution abatement actions and the implications of the biological monitoring effort to environmental management is the subject of this special issue of Environmental Management. This final article focuses on the synthesis of the biological monitoring program's components and methods, the efficacy of various biological monitoring techniques to environmental management, and the lessons learned from the program that might be applicable to the design and application of other programs. The focus of the 25-year program has been on East Fork Poplar Creek, an ecologically impaired stream in Oak Ridge, Tennessee with varied and complex stressors from a Department of Energy facility in its headwaters. Major components of the long-term program included testing and monitoring of invertebrate and fish toxicity, bioindicators of fish health, fish contaminant accumulation, and instream communities (including periphyton, benthic macroinvertebrate, and fish). Key parallel components of the program include water chemistry sampling and data management. Multiple lines of evidence suggested positive ecological responses during three major pollution abatement periods. Based on this case study and the related literature, effective environmental management of impaired streams starts with program design that is consistent across space and time, but also adaptable to changing conditions. The biological monitoring approaches used for the program provided a strong basis for assessments of recovery from remedial actions, and the likely causes of impairment. This case study provides a unique application of multidisciplinary and quantitative techniques to address multiple and complex regulatory and programmatic goals, environmental stressors, and remedial actions.

  3. Long-term Biological Monitoring of an Impaired Stream: Synthesis and Environmental Management Implications

    SciTech Connect

    Peterson, Mark J; Efroymson, Rebecca Ann; Adams, Marshall

    2011-01-01

    The long-term ecological recovery of an impaired stream in response to an industrial facility's pollution abatement actions and the implications of the biological monitoring effort to environmental management is the subject of this special issue of Environmental Management. This final article focuses on the synthesis of the biological monitoring program's components and methods, the efficacy of various biological monitoring techniques to environmental management, and the lessons learned from the program that might be applicable to the design and application of other programs. The focus of the 25-year program has been on East Fork Poplar Creek, an ecologically impaired stream in Oak Ridge, Tennessee with varied and complex stressors from a Department of Energy facility in its headwaters. Major components of the long-term program included testing and monitoring of invertebrate and fish toxicity, bioindicators of fish health, fish contaminant accumulation, and instream communities (including periphyton, benthic macroinvertebrate, and fish). Key parallel components of the program include water chemistry sampling and data management. Multiple lines of evidence suggested positive ecological responses during three major pollution abatement periods. Based on this case study and the related literature, effective environmental management of impaired streams starts with program design that is consistent across space and time, but also adaptable to changing conditions. The biological monitoring approaches used for the program provided a strong basis for assessments of recovery from remedial actions, and the likely causes of impairment. This case study provides a unique application of multidisciplinary and quantitative techniques to address multiple and complex regulatory and programmatic goals, environmental stressors, and remedial actions.

  4. Long-Term Biological Monitoring of an Impaired Stream: Synthesis and Environmental Management Implications

    NASA Astrophysics Data System (ADS)

    Peterson, Mark J.; Efroymson, Rebecca A.; Adams, S. Marshall

    2011-06-01

    The long-term ecological recovery of an impaired stream in response to an industrial facility's pollution abatement actions and the implications of the biological monitoring effort to environmental management is the subject of this special issue of Environmental Management. This final article focuses on the synthesis of the biological monitoring program's components and methods, the efficacy of various biological monitoring techniques to environmental management, and the lessons learned from the program that might be applicable to the design and application of other programs. The focus of the 25-year program has been on East Fork Poplar Creek, an ecologically impaired stream in Oak Ridge, Tennessee with varied and complex stressors from a Department of Energy facility in its headwaters. Major components of the long-term program included testing and monitoring of invertebrate and fish toxicity, bioindicators of fish health, fish contaminant accumulation, and instream communities (including periphyton, benthic macroinvertebrate, and fish). Key parallel components of the program include water chemistry sampling and data management. Multiple lines of evidence suggested positive ecological responses during three major pollution abatement periods. Based on this case study and the related literature, effective environmental management of impaired streams starts with program design that is consistent across space and time, but also adaptable to changing conditions. The biological monitoring approaches used for the program provided a strong basis for assessments of recovery from remedial actions, and the likely causes of impairment. This case study provides a unique application of multidisciplinary and quantitative techniques to address multiple and complex regulatory and programmatic goals, environmental stressors, and remedial actions.

  5. Solar Transmission Through Sea Ice in the Fram Strait: Implications for Biology and Climate

    NASA Astrophysics Data System (ADS)

    Hudson, S.; Reigstad, M.; Gerland, S.; Nicolaus, M.; Nicolaus, A.

    2008-12-01

    Snow and ice control the light penetration into ice-covered Arctic waters, determining the onset of biological production after the winter. Changes in the snow and ice cover and their characteristics influence both the amount of light and the spectral distribution of light transmitted to the underlying water, with effects on timing, distribution, production rate and even species composition of the Arctic marine production. Light transmitted through the sea ice also provides a source of heat to the upper part of the water column, and may promote melting of the ice from the bottom. Spectral measurements of the transmitted solar flux were made at several locations in the Fram Strait-East Greenland Shelf region in April---May 2008, as part of the iAOOS-Norway project of interdisciplinary observations in the Arctic Ocean, and in September 2007 and 2008. These transmission measurements were made both immediately below ice floes, and as profiles to a depth of 80~m both beneath floes and beneath open water in leads. During the spring cruise, the corresponding biological productivity and biomass in the water column below the ice were measured. Together such data will increase our understanding of how a changing Arctic climate will influence the ecosystem and productivity. This presentation will present results from these transmission measurements, the first of their kind from this important region of sea ice export and biological and oceanographic activity, and their relationship to biological productivity, along with their implications for climate processes, including the formation and melting of sea ice.

  6. Occurrence, pathways and implications of biological production of reactive oxygen species in natural waters

    NASA Astrophysics Data System (ADS)

    Zhang, T.; Hansel, C. M.; Voelker, B. M.; Lamborg, C. H.

    2014-12-01

    Reactive oxygen species (ROS), such as superoxide (O2-) and hydrogen peroxide (H2O2) play a critical role in the redox cycling of both toxic (e.g., Hg) and nutrient (e.g., Fe) metals. Despite the discovery of extracellular ROS production in various microbial cultures, including fungi, algae and bacteria, photo-dependent processes are generally considered as the predominant source of ROS in natural waters. Here we show that biological production of ROS is ubiquitous and occurs at a significant rate in freshwater and brackish water environments. Water samples were collected from three freshwater and one brackish water ponds in Cape Cod, Massachusetts, USA, periodically from 2012 to 2014. Production of O2- and H2O2 were measured in dark incubations of natural water using a chemiluminescent and a colorimetric probe, respectively. Rates of biological ROS production were obtained by comparing unfiltered with 0.2-μm filtered samples. The role of biological activity in ROS production was confirmed by the cessation of ROS production upon addition of formaldehyde. In surface water, production rates of O2- ranged from undetectable to 96.0 ± 30.0 nmol L-1 h-1, and production rates of H2O2 varied between 9.9 ± 1.3 nmol L-1 h-1 and 145.6 ± 11.2 nmol L-1 h-1. The maximum production rates of both ROS were observed in mid-summer 2013, which coincides with peak biological activity. ROS production in the water from aphotic zone was greater than in the water from photic zone. Thus, non-light dependent biological processes are likely the major contributors to ROS production in this system. Moreover, O2- production appeared to be enhanced by NADH and inhibited by proteinase-K, suggesting the possible involvement of NADH oxidoreductases in this process. The potential role of different microbial communities in ROS production, and the implications of biological ROS production for mercury speciation will also be discussed.

  7. Subject-specific pedagogical content knowledge: Implications for alternatively and traditionally trained biology teachers

    NASA Astrophysics Data System (ADS)

    Ravgiala, Rebekah Rae

    Theories regarding the development of expertise hold implications for alternative and traditional certification programs and the teachers they train. The literature suggests that when compared to experts in the field of teaching, the behaviors of novices differ in ways that are directly attributed to their pedagogical content knowledge. However, few studies have examined how first and second year biology teachers entering the profession from traditional and alternative training differ in their demonstration of subject-specific pedagogical content knowledge. The research problem in this multicase, naturalistic inquiry investigated how subject-specific pedagogical content knowledge was manifested among first and second year biology teachers in the task of transforming subject matter into forms that are potentially meaningful to students when explicit formal training has been and has not been imparted to them as preservice teachers. Two first year and two second year biology teachers were the subjects of this investigation. Allen and Amber obtained their certification through an alternative summer training institute in consecutive years. Tiffany and Tricia obtained their certification through a traditional, graduate level training program in consecutive years. Both programs were offered at the same northeastern state university. Participants contributed to six data gathering techniques including an initial semi-structured interview, responses to the Conceptions of Teaching Science questionnaire (Hewson & Hewson, 1989), three videotaped biology lessons, evaluation of three corresponding lesson plans, and a final semi-structured interview conducted at the end of the investigation. An informal, end-of-study survey intended to offer participants an opportunity to disclose their thoughts and needs as first year teachers was also employed. Results indicate that while conceptions of teaching science may vary slightly among participants, there is no evidence to suggest that

  8. A fractal model for nuclear organization: current evidence and biological implications

    PubMed Central

    Bancaud, Aurélien; Lavelle, Christophe; Huet, Sébastien; Ellenberg, Jan

    2012-01-01

    Chromatin is a multiscale structure on which transcription, replication, recombination and repair of the genome occur. To fully understand any of these processes at the molecular level under physiological conditions, a clear picture of the polymorphic and dynamic organization of chromatin in the eukaryotic nucleus is required. Recent studies indicate that a fractal model of chromatin architecture is consistent with both the reaction-diffusion properties of chromatin interacting proteins and with structural data on chromatin interminglement. In this study, we provide a critical overview of the experimental evidence that support a fractal organization of chromatin. On this basis, we discuss the functional implications of a fractal chromatin model for biological processes and propose future experiments to probe chromatin organization further that should allow to strongly support or invalidate the fractal hypothesis. PMID:22790985

  9. Neural systems implicated in obesity as an addictive disorder: from biological to behavioral mechanisms.

    PubMed

    Schulte, Erica M; Yokum, Sonja; Potenza, Marc N; Gearhardt, Ashley N

    2016-01-01

    Contributing factors to obesity have been identified, yet prevention and treatment efforts have had limited long-term success. It has recently been suggested that some individuals may experience an addictive-like response to certain foods, such as losing control over consumption and continued consumption despite negative consequences. In support, shared biological and behavioral features seem to exist between "food addiction" and traditional substance-use disorders. "Food addiction" may be another important contributor to obesity. The current chapter reviews existing literature regarding neural systems implicated similarly in obesity and addiction, discusses unique considerations for addictive-like eating, and proposes directions for future research regarding "food addiction" as an emerging construct for addiction medicine. © 2016 Elsevier B.V. All rights reserved.

  10. Cytosol-dependent membrane fusion in ER, nuclear envelope and nuclear pore assembly: biological implications.

    PubMed

    Rafikova, Elvira R; Melikov, Kamran; Chernomordik, Leonid V

    2010-01-01

    Endoplasmic reticulum and nuclear envelope rearrangements after mitosis are often studied in the reconstitution system based on Xenopus egg extract. In our recent work we partially replaced the membrane vesicles in the reconstitution mix with protein-free liposomes to explore the relative contributions of cytosolic and transmembrane proteins. Here we discuss our finding that cytosolic proteins mediate fusion between membranes lacking functional transmembrane proteins and the role of membrane fusion in endoplasmic reticulum and nuclear envelope reorganization. Cytosol-dependent liposome fusion has allowed us to restore, without adding transmembrane nucleoporins, functionality of nuclear pores, their spatial distribution and chromatin decondensation in nuclei formed at insufficient amounts of membrane material and characterized by only partial decondensation of chromatin and lack of nuclear transport. Both the mechanisms and the biological implications of the discovered coupling between spatial distribution of nuclear pores, chromatin decondensation and nuclear transport are discussed.

  11. Cell and molecular biology of intervertebral disc degeneration: current understanding and implications for potential therapeutic strategies.

    PubMed

    Wang, S Z; Rui, Y F; Lu, J; Wang, C

    2014-10-01

    Intervertebral disc degeneration (IDD) is a chronic, complex process associated with low back pain; mechanisms of its occurrence have not yet been fully elucidated. Its process is not only accompanied by morphological changes, but also by systematic changes in its histological and biochemical properties. Many cellular and molecular mechanisms have been reported to be related with IDD and to reverse degenerative trends, abnormal conditions of the living cells and altered cell phenotypes would need to be restored. Promising biological therapeutic strategies still rely on injection of active substances, gene therapy and cell transplantation. With advanced study of tissue engineering protocols based on cell therapy, combined use of seeding cells, bio-active substances and bio-compatible materials, are promising for IDD regeneration. Recently reported progenitor cells within discs themselves also hold prospects for future IDD studies. This article describes the background of IDD, current understanding and implications of potential therapeutic strategies.

  12. Green tea catechins: biologic properties, proposed mechanisms of action, and clinical implications.

    PubMed

    Rosen, Ted

    2012-11-01

    Botanical products, including and especially green tea leaves, have a wide range of both reputed and demonstrated health benefits and have been used medicinally for thousands of years. This paper focuses on green tea catechins, principally reviewing their known biologic properties and potential mechanisms of action (MOAs). The primary objective is to discuss the proposed antiviral, antiproliferative, and immunostimulatory activity of catechins based on strong evidence from in vitro and in vivo studies conducted to date, including two preclinical in vitro studies with sinecatechins, a proprietary mixture of catechins. This review also discusses the clinical implications of catechins for the treatment of external genital and perianal warts (EGWs) and other conditions caused by human papillomavirus (HPV). While the MOA of catechins in the treatment of EGWs and other HPV-related conditions may be related to or associated with postulated or proven antiviral and immunostimulatory activity, the precise clinical significance of the various in vitro findings remains largely unknown.

  13. Biologic Mechanisms of Oral Cancer Pain and Implications for Clinical Therapy

    PubMed Central

    Viet, C.T.; Schmidt, B.L.

    2012-01-01

    Cancer pain is an ever-present public health concern. With innovations in treatment, cancer patients are surviving longer, but uncontrollable pain creates a poor quality of life for these patients. Oral cancer is unique in that it causes intense pain at the primary site and significantly impairs speech, swallowing, and masticatory functions. We propose that oral cancer pain has underlying biologic mechanisms that are generated within the cancer microenvironment. A comprehensive understanding of key mediators that control cross-talk between the cancer and peripheral nervous system, and possible interventions, underlies effective cancer pain management. The purpose of this review is to explore the current studies on oral cancer pain and their implications in clinical management for cancer pain in general. Furthermore, we will explore the endogenous opioid systems and novel cancer pain therapeutics that target these systems, which could solve the issue of opiate tolerance and improve quality of life in oral cancer patients. PMID:21972258

  14. A fractal model for nuclear organization: current evidence and biological implications.

    PubMed

    Bancaud, Aurélien; Lavelle, Christophe; Huet, Sébastien; Ellenberg, Jan

    2012-10-01

    Chromatin is a multiscale structure on which transcription, replication, recombination and repair of the genome occur. To fully understand any of these processes at the molecular level under physiological conditions, a clear picture of the polymorphic and dynamic organization of chromatin in the eukaryotic nucleus is required. Recent studies indicate that a fractal model of chromatin architecture is consistent with both the reaction-diffusion properties of chromatin interacting proteins and with structural data on chromatin interminglement. In this study, we provide a critical overview of the experimental evidence that support a fractal organization of chromatin. On this basis, we discuss the functional implications of a fractal chromatin model for biological processes and propose future experiments to probe chromatin organization further that should allow to strongly support or invalidate the fractal hypothesis.

  15. Surface-enhanced Raman spectroscopy at single-molecule scale and its implications in biology.

    PubMed

    Wang, Yuling; Irudayaraj, Joseph

    2013-02-05

    Single-molecule (SM) spectroscopy has been an exciting area of research offering significant promise and hope in the field of sensor development to detect targets at ultra-low levels down to SM resolution. To the experts and developers in the field of surface-enhanced Raman spectroscopy (SERS), this has often been a challenge and a significant opportunity for exploration. Needless to say, the opportunities and excitement of this multidisciplinary area impacts span the fields of physics, chemistry and engineering, along with a significant thrust in applications constituting areas in medicine, biology, environment and agriculture among others. In this review, we will attempt to provide a quick snapshot of the basics of SM-SERS, nanostructures and devices that can enable SM Raman measurement. We will conclude with a discussion on SERS implications in biomedical sciences.

  16. Software Architecture to Support the Evolution of the ISRU RESOLVE Engineering Breadboard Unit 2 (EBU2)

    NASA Technical Reports Server (NTRS)

    Moss, Thomas; Nurge, Mark; Perusich, Stephen

    2011-01-01

    The In-Situ Resource Utilization (ISRU) Regolith & Environmental Science and Oxygen & Lunar Volatiles Extraction (RESOLVE) software provides operation of the physical plant from a remote location with a high-level interface that can access and control the data from external software applications of other subsystems. This software allows autonomous control over the entire system with manual computer control of individual system/process components. It gives non-programmer operators the capability to easily modify the high-level autonomous sequencing while the software is in operation, as well as the ability to modify the low-level, file-based sequences prior to the system operation. Local automated control in a distributed system is also enabled where component control is maintained during the loss of network connectivity with the remote workstation. This innovation also minimizes network traffic. The software architecture commands and controls the latest generation of RESOLVE processes used to obtain, process, and quantify lunar regolith. The system is grouped into six sub-processes: Drill, Crush, Reactor, Lunar Water Resource Demonstration (LWRD), Regolith Volatiles Characterization (RVC) (see example), and Regolith Oxygen Extraction (ROE). Some processes are independent, some are dependent on other processes, and some are independent but run concurrently with other processes. The first goal is to analyze the volatiles emanating from lunar regolith, such as water, carbon monoxide, carbon dioxide, ammonia, hydrogen, and others. This is done by heating the soil and analyzing and capturing the volatilized product. The second goal is to produce water by reducing the soil at high temperatures with hydrogen. This is done by raising the reactor temperature in the range of 800 to 900 C, causing the reaction to progress by adding hydrogen, and then capturing the water product in a desiccant bed. The software needs to run the entire unit and all sub-processes; however

  17. Current and emerging basic science concepts in bone biology: implications in craniofacial surgery.

    PubMed

    Oppenheimer, Adam J; Mesa, John; Buchman, Steven R

    2012-01-01

    Ongoing research in bone biology has brought cutting-edge technologies into everyday use in craniofacial surgery. Nonetheless, when osseous defects of the craniomaxillofacial skeleton are encountered, autogenous bone grafting remains the criterion standard for reconstruction. Accordingly, the core principles of bone graft physiology continue to be of paramount importance. Bone grafts, however, are not a panacea; donor site morbidity and operative risk are among the limitations of autologous bone graft harvest. Bone graft survival is impaired when irradiation, contamination, and impaired vascularity are encountered. Although the dura can induce calvarial ossification in children younger than 2 years, the repair of critical-size defects in the pediatric population may be hindered by inadequate bone graft donor volume. The novel and emerging field of bone tissue engineering holds great promise as a limitless source of autogenous bone. Three core constituents of bone tissue engineering have been established: scaffolds, signals, and cells. Blood supply is the sine qua non of these components, which are used both individually and concertedly in regenerative craniofacial surgery. The discerning craniofacial surgeon must determine the proper use for these bone graft alternatives, while understanding their concomitant risks. This article presents a review of contemporary and emerging concepts in bone biology and their implications in craniofacial surgery. Current practices, areas of controversy, and near-term future applications are emphasized.

  18. Obesity Paradox in Lung Cancer Prognosis: Evolving Biological Insights and Clinical Implications.

    PubMed

    Zhang, Xueli; Liu, Yamin; Shao, Hua; Zheng, Xiao

    2017-10-01

    The survival rate of lung cancer remains low despite the progress of surgery and chemotherapy. With the increasing comorbidity of obesity in patients with lung cancer, new challenges are emerging in the management of this patient population. A key issue of interest is the prognostic effect of obesity on surgical and chemotherapeutic outcomes in patients with lung cancer, which is fueled by the growing observation of survival benefits in overweight or obese patients. This unexpected inverse relationship between obesity and lung cancer mortality, called the obesity paradox, remains poorly understood. The evolving insights into the heterogeneity of obesity phenotypes and associated biological connections with lung cancer progression in recent years may help explain some of the seemingly paradoxical relationship, and well-designed clinical studies looking at the causal role of obesity-associated molecules are expected. Here, we examine potential biological mechanisms behind the protective effects of obesity in lung cancer. We highlight the need to clarify the clinical implications of this relationship toward an updated intervention strategy in the clinical care of patients with lung cancer and obesity. Copyright © 2017 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

  19. Differential characteristics of olive pollen from different cultivars: biological and clinical implications.

    PubMed

    Alché, J D; Castro, A J; Jiménez-López, J C; Morales, S; Zafra, A; Hamman-Khalifa, A M; Rodríguez-García, M I

    2007-01-01

    The olive tree is grown in many parts of the world. Its germplasm is very broad, with 250 varieties in Spain alone. Variations in the ability of pollen to germinate have been studied in detail and show conspicuous differences between varieties. However, commercial olive pollen from cultivars whose origin is unknown is the material that is commonly used for clinical and biological studies. We aim to assess the putative heterogeneity of olive cultivars with regard to the presence of several pollen allergens and to determine whether these differences have biological and clinical relevance. Previous studies show that most allergens isolated and characterized to date are highly polymorphic. Olive cultivars display wide differences in the expression levels of many allergens and in the number and molecular characteristics of the allergen isoforms expressed. These differences are maintained over the years, and are intrinsic to the genetics of each cultivar. Such broad polymorphism seems to be involved in the physiology of the olive reproductive system, which might include the adaptation of the plant to different environmental conditions, the establishment of the compatibility system, and pollen performance. The differences in allergen composition in cultivars, particularly in the Ole e 1 allergen, are responsible for the important differences in the allergenic potency of the extracts. These findings could have a number of implications for the diagnosis and therapy of olive pollen allergy. We discuss how cultivar differences affect extract quality, diagnostic and therapeutic efficacy and safety, and the development of new vaccines based on the use of recombinant allergens.

  20. Physical descriptions of the bacterial nucleoid at large scales, and their biological implications

    NASA Astrophysics Data System (ADS)

    Benza, Vincenzo G.; Bassetti, Bruno; Dorfman, Kevin D.; Scolari, Vittore F.; Bromek, Krystyna; Cicuta, Pietro; Cosentino Lagomarsino, Marco

    2012-07-01

    Recent experimental and theoretical approaches have attempted to quantify the physical organization (compaction and geometry) of the bacterial chromosome with its complement of proteins (the nucleoid). The genomic DNA exists in a complex and dynamic protein-rich state, which is highly organized at various length scales. This has implications for modulating (when not directly enabling) the core biological processes of replication, transcription and segregation. We overview the progress in this area, driven in the last few years by new scientific ideas and new interdisciplinary experimental techniques, ranging from high space- and time-resolution microscopy to high-throughput genomics employing sequencing to map different aspects of the nucleoid-related interactome. The aim of this review is to present the wide spectrum of experimental and theoretical findings coherently, from a physics viewpoint. In particular, we highlight the role that statistical and soft condensed matter physics play in describing this system of fundamental biological importance, specifically reviewing classic and more modern tools from the theory of polymers. We also discuss some attempts toward unifying interpretations of the current results, pointing to possible directions for future investigation.

  1. Epistatic interactions of AKT1 on human medial temporal lobe biology and pharmacogenetic implications

    PubMed Central

    Tan, H Y; Chen, A G; Chen, Q; Browne, L B; Verchinski, B; Kolachana, B; Zhang, F; Apud, J; Callicott, J H; Mattay, V S; Weinberger, D R

    2012-01-01

    AKT1 controls important processes in medial temporal lobe (MTL) development and plasticity, but the impact of human genetic variation in AKT1 on these processes is not known in healthy or disease states. Here, we report that an AKT1 variant (rs1130233) previously associated with AKT1 protein expression, prefrontal function and schizophrenia, affects human MTL structure and memory function. Further, supporting AKT1's role in transducing hippocampal neuroplasticity and dopaminergic processes, we found epistasis with functional polymorphisms in BDNF and COMT—genes also implicated in MTL biology related to AKT1. Consistent with prior predictions that these biologic processes relate to schizophrenia, we found epistasis between the same AKT1, BDNF and COMT functional variants on schizophrenia risk, and pharmacogenetic interactions of AKT1 with the effects on cognition and brain volume measures by AKT1 activators in common clinical use—lithium and sodium valproate. Our findings suggest that AKT1 affects risk for schizophrenia and accompanying cognitive deficits, at least in part through specific genetic interactions related to brain neuroplasticity and development, and that these AKT1 effects may be pharmacologically modulated in patients. PMID:21788944

  2. Reduction and S-nitrosation of the neuropeptide oxytocin: implications for its biological function.

    PubMed

    Roy, Jean-François; Chrétien, Michelle N; Woodside, Barbara; English, Ann M

    2007-09-01

    Oxytocin (OT; Cys-Tyr-Ile-Gln-Asn-Cys-Pro-leu-Gly), a posterior pituitary peptide hormone, is characterized by a Cys1-Cys6 disulfide bond in its stable, isolated state. This paper describes a simple, one-step method for the production of OT in its reduced, dithiol form (OT dithiol), free of reducing agent. The effects of temperature, pH, and metal-ion chelators on the autoxidation of OT dithiol were examined to establish if this form is likely to persist under biological conditions. It was found that OT dithiol has a half-life of 1.8h with respect to reformation of OT disulfide at 37 degrees C and pH 6.9 in the presence of the copper chelators, DTPA and neocuproine. S-Nitrosation of OT dithiol by acidified nitrite at pH 3.0 was examined by absorption spectroscopy and HPLC-UV-MS, which revealed that both singly and doubly S-nitrosated OT are formed. These results suggest novel chemical aspects to OT signaling, the biological implications of which are discussed here.

  3. Self-Organisation, Thermotropic and Lyotropic Properties of Glycolipids Related to their Biological Implications

    PubMed Central

    Garidel, Patrick; Kaconis, Yani; Heinbockel, Lena; Wulf, Matthias; Gerber, Sven; Munk, Ariane; Vill, Volkmar; Brandenburg, Klaus

    2015-01-01

    Glycolipids are amphiphilic molecules which bear an oligo- or polysaccharide as hydrophilic head group and hydrocarbon chains in varying numbers and lengths as hydrophobic part. They play an important role in life science as well as in material science. Their biological and physiological functions are quite diverse, ranging from mediators of cell-cell recognition processes, constituents of membrane domains or as membrane-forming units. Glycolipids form an exceptional class of liquid-crystal mesophases due to the fact that their self-organisation obeys more complex rules as compared to classical monophilic liquid-crystals. Like other amphiphiles, the supra-molecular structures formed by glycolipids are driven by their chemical structure; however, the details of this process are still hardly understood. Based on the synthesis of specific glycolipids with a clearly defined chemical structure, e.g., type and length of the sugar head group, acyl chain linkage, substitution pattern, hydrocarbon chain lengths and saturation, combined with a profound physico-chemical characterisation of the formed mesophases, the principles of the organisation in different aggregate structures of the glycolipids can be obtained. The importance of the observed and formed phases and their properties are discussed with respect to their biological and physiological relevance. The presented data describe briefly the strategies used for the synthesis of the used glycolipids. The main focus, however, lies on the thermotropic as well as lyotropic characterisation of the self-organised structures and formed phases based on physico-chemical and biophysical methods linked to their potential biological implications and relevance. PMID:26464591

  4. In vitro study of the biological interface of Bio-Oss: implications of the experimental setup.

    PubMed

    Mladenović, Živko; Sahlin-Platt, Annika; Andersson, Britta; Johansson, Anders; Björn, Erik; Ransjö, Maria

    2013-03-01

    To systematically investigate the biological interface of Bio-Oss by analysing dissolution-precipitation behaviour and osteogenic responses using in vitro experimental systems. Different concentrations (1-100 mg/ml) of Bio-Oss were incubated in cell culture medium for 24 h before elemental concentrations for calcium, phosphorus and silicon in the medium were analysed with inductive coupled plasma-optical emission spectroscopy. Radioactive calcium-45 isotope labelling technique was used to study possible precipitation of calcium on the Bio-Oss particle. Biological interface of Bio-Oss was studied in osteogenic experiments using mineralization medium and three different sources of cells (primary mouse bone marrow stromal cells, primary rat calvarial cells and MC3T3-E1 mouse pre-osteoblast cell line). Cells were fixed and stained with Toulidine blue, von Kossa or Alizarin Red staining for confirmation of extracellular matrix mineralization. Elemental analysis of the cell culture medium demonstrated a significant decrease of calcium and phosphorus and a dose-dependent release of silicon to the medium after incubation with Bio-Oss. A significant decrease of calcium and phosphorus in the medium occurred even at low concentrations of Bio-Oss. Uptake of calcium on the Bio-Oss particle was confirmed with radioactive calcium-45 isotope labelling technique. In osteogenic experiments with Bio-Oss (<1 mg/ml), matrix mineralization around the Bio-Oss particles were demonstrated in all three cell types with von Kossa and Alizarin Red staining. Dissolution-precipitation reactions occur at the surface of Bio-Oss, and osteogenic responses are seen at the biological interface. The concentration of Bio-Oss is a key factor for the experimental in vitro results, and may also have implications for the clinic. © 2011 John Wiley & Sons A/S.

  5. An Advanced In-Situ Resource Utilization (ISRU) Production Plant Design for Robotic and Human Mars Missions

    NASA Astrophysics Data System (ADS)

    Simon, T.; Baird, R. S.; Trevathan, J.; Clark, L.

    2002-01-01

    The ability to produce the necessary consumables, rather than relying solely on what is brought from Earth decreases the launch mass, cost, and risk associated with a Mars mission while providing capabilities that enable the commercial development of space. The idea of using natural resources, or "living off the land", is termed In-Situ Resource Utilization (ISRU). Trade studies have shown that producing and utilizing consumables such as water, breathing oxygen, and propellant can reduce the launch mass for a human or robotic mission to Mars by 20-45%. The Johnson Space Center and Lockheed Martin Astronautics are currently designing and planning assembly of a complete collection-to-storage production plant design for producing methane (fuel), oxygen, and water from carbon dioxide (Martian atmosphere) and hydrogen (electrolyzed Martian water or Earth-originated), based on lessons learned and design enhancements from a 1st generation testbed. The design and testing of the major subsystems incorporated in the 2nd generation system, including a carbon dioxide freezer, Sabatier reactor, water electrolysis unit, and vacuum-jacketed, cryogenic, common-bulkhead storage tank, will be presented in detail with the goal of increasing the awareness of the readiness level of these technologies. These technologies are mass and power efficient as well as fundamentally simple and reliable. These technologies also have potential uses in Environmental Control and Life Support System (ECLSS) applications for removing and recycling crew-exhaled carbon dioxide. Each subsystem is sized for an ISRU-assisted sample return mission, producing in an 8-hour period 0.56 kg water and 0.26 kg methane from the Sabatier reactor and 0.50 kg oxygen from electrolyzed water. The testing of these technologies to date will be discussed as well as plans for integrating the subsystems for a complete end-to-end demonstration at Mars conditions. This paper will also address the history of these subsystem

  6. The use of passerine bird species in laboratory research: implications of basic biology for husbandry and welfare.

    PubMed

    Bateson, Melissa; Feenders, Gesa

    2010-01-01

    Passerine birds are important models in fundamental biological research, with as many as 300,000 individuals used in laboratory experiments worldwide annually. However, because the use of passerines is rare compared with that of more conventional laboratory animals, there is often a lack of information about the basic biology and husbandry requirements of these species. We aim to address this deficit by providing an overview of the most salient aspects of passerine biology and their implications for laboratory husbandry and welfare. We start by describing the characteristics that make these birds useful and interesting research subjects. Specifically, we highlight features (e.g., birdsong) of passerine biology that differentiate these birds from more common laboratory animals. Next, we consider the implications of passerine biology for husbandry in the laboratory. Many of the aspects of passerine biology that make these species valuable to scientists are also likely to be affected by environmental variables; a good knowledge of these variables is necessary in order to choose appropriate laboratory conditions for passerines. We outline how the developmental history of the birds and choices of caging, feeding, and environmental regimes might influence their physiology and behavior and thus affect both the welfare of the birds and the quality of the resulting data. We stress the importance of a sound understanding of the biology of any species to ensure good welfare and good science.

  7. Formation of Nanophase Iron in Lunar Soil Simulant for Use in ISRU Studies

    NASA Technical Reports Server (NTRS)

    Liu, Yang; Taylor, Lawrence A.; Hill, Eddy; Day, James D. M.

    2005-01-01

    discovered the presence of abundant np-Fe(sup 0) particles in the glass patinas coating most soil particles. Therefore, the correlation of glass content and magnetic susceptibility can be explained by the presence of the np-Feo particles in glass: small particles contain relatively more np-Fe(sup 0) as glass coatings because the surface area versus mass ratio of the grain size is so increased. The magnetic properties of lunar soil are important in dust mitigation on the Moon (Taylor et al. 2005). Thus material simulating this property is important for testing mitigation methods using electromagnetic field. This np- Fe(sup 0) also produces a unique energy coupling to normal microwaves, such as present in kitchen microwave ovens. Effectively, a portion of lunar soil placed in a normal 2.45 GHz oven will melt at greater than 1200 C before your tea will boil at 100 C, a startling and new discovery reported by Taylor and Meek (2004, 2005). Several methods have been investigated in attempts to make nanophase-sized Feo dispersed within silicate glass; like in the lunar glass. We have been successful in synthesizing such a product and continue to improve on our recipe. We have performed extensive experimentation on this subject to date. Ultimately it will probably be necessary to add this np-Fe(sup 0) bearing silicate glass to lunar soil stimulant, like JSC-1, to actually produce the desired magnetic and microwave coupling properties for use in appropriate ISRU experimentation.

  8. ISRU-Based Robotic Construction Technologies For Lunar And Martian Infrastructures

    NASA Technical Reports Server (NTRS)

    Khoshnevis, Behrokh; Carlson, Anders; Thangavelu, Madhu

    2017-01-01

    Economically viable and reliable building systems and tool sets are being sought, examined and tested for extraterrestrial infrastructure buildup. This project utilizes a unique architecture weaving the robotic building construction technology with designs for assisting rapid buildup of initial operational capability Lunar and Martian bases. The project intends to develop and test methodologies to construct certain crucial infrastructure elements in order to evaluate the merits, limitations and feasibility of adapting and using such technologies for extraterrestrial application. High priority infrastructure elements suggested by our NASA advisors to be considered include landing pads and aprons, roads, blast walls and shade walls, thermal and micrometeorite protection shields and dust-free platforms utilizing the well-known insitu resource utilization (ISRU) strategy. Current extraterrestrial settlement buildup philosophy holds that in order to minimize the materials needed to be flown in, at great transportation costs, strategies that maximize the use of locally available resources must be adopted. Tools and heavy equipment flown as cargo from Earth are proposed to build required infrastructure to support future missions and settlements on the Moon and Mars. Several unique systems including the Lunar Electric Rover, the unpressurized Chariot rover, the versatile light-weight crane and Tri-Athlete cargo transporter as well as the habitat module mockups and a new generation of spacesuits are undergoing coordinated tests at NASAs D-RATS. This project intends to draw up a detailed synergetic plan to utilize these maturing systems coupled with modern robotic fabrication technologies based primarily on 3D Printing, tailored for swift and reliable Lunar and Martian infrastructure development. This project also intends to increase astronaut safety, improve buildup performance, ameliorate dust interference and concerns, and reduce time-to-commission, all in an economic

  9. Quantum nature of photon signal emitted by Xanthoria parietina and its implications to biology.

    PubMed

    Bajpai, R P

    2008-05-01

    The properties of living systems are usually described in the semi-classical framework that makes phenomenological division of properties into four classes--matter, psyche, soft consciousness and hard consciousness. Quantum framework provides a scientific basis of this classification of properties. The scientific basis requires the existence of macroscopic quantum entity entangled with quantum photon field of a living system. Every living system emits a photon signal with features indicating its quantum nature. Quantum nature of the signal emitted by a sample of X. parietina is confirmed by analysing photo count distributions obtained in 20000 measurements of photon number in contiguous bins of sizes of 50, 100, 200, 300 and 500 ms. The measurements use a broadband detector sensitive in 300-800 nm range (Photo count distributions of background noise and observed signal are measured similarly. These measurements background noise corrected squeezed state parameters of the signal. The parameters are signal strength expressed in counts per bin, r = 0.06, theta = 2.76 and phi = 0.64. The parameters correctly reproduce photo count distribution of any bin size in 50 ms-6 s range. The reproduction of photo count distributions is a credible evidence of spontaneous emission of photon signal in a quantum squeezed state for macroscopic time by the sample. The evidence is extrapolated to other living systems emitting similar photon signals. It is suggested that every living system is associated with a photon field in squeezed state. The suggestion has far reaching implications to biology and provides two ways of observing and manipulating a living system--either through matter or field or a combination of the two. Some implications and possible scenarios are elaborated.

  10. Are humans prone to autoimmunity? Implications from evolutionary changes in hominin sialic acid biology.

    PubMed

    Varki, Ajit

    2017-09-01

    Given varied intrinsic and extrinsic challenges to the immune system, it is unsurprising that each evolutionary lineage evolves distinctive features of immunoreactivity, and that tolerance mechanisms fail, allowing autoimmunity. Humans appear prone to many autoimmune diseases, with mechanisms both genetic and environmental. Another rapidly evolving biological system involves sialic acids, a family of monosaccharides that are terminal caps on cell surface and secreted molecules of vertebrates, and play multifarious roles in immunity. We have explored multiple genomic changes in sialic acid biology that occurred in human ancestors (hominins), some with implications for enhanced immunoreactivity, and hence for autoimmunity. Human ancestors lost the enzyme synthesizing the common mammalian sialic acid Neu5Gc, with an accumulation of the precursor sialic acid Neu5Ac. Resulting changes include an enhanced reactivity by some immune cells and increased ability of macrophages to kill bacteria, at the cost of increased endotoxin sensitivity. There are also multiple human-specific evolutionary changes in inhibitory and activating Siglecs, immune cell receptors that recognize sialic acids as "self-associated molecular patterns" (SAMPs) to modulate immunity, but can also be hijacked by pathogen molecular mimicry of SAMPs. Altered expression patterns and fixed or polymorphic SIGLEC pseudogenization in humans has modulated both innate and adaptive immunity, sometimes favoring over-reactivity. Meanwhile, dietary intake of Neu5Gc (derived primarily from red meats) allows metabolic incorporation of this non-human molecule into human cells--apparently the first example of "xeno-autoimmunity" involving "xeno-autoantigen" interactions with circulating "xeno-autoantibodies". Taken together, some of these factors may contribute to the apparent human propensity for autoimmunity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Very small embryonic-like stem cells: implications in reproductive biology.

    PubMed

    Bhartiya, Deepa; Unni, Sreepoorna; Parte, Seema; Anand, Sandhya

    2013-01-01

    The most primitive germ cells in adult mammalian testis are the spermatogonial stem cells (SSCs) whereas primordial follicles (PFs) are considered the fundamental functional unit in ovary. However, this central dogma has recently been modified with the identification of a novel population of very small embryonic-like stem cells (VSELs) in the adult mammalian gonads. These stem cells are more primitive to SSCs and are also implicated during postnatal ovarian neo-oogenesis and primordial follicle assembly. VSELs are pluripotent in nature and characterized by nuclear Oct-4A, cell surface SSEA-4, and other pluripotent markers like Nanog, Sox2, and TERT. VSELs are considered to be the descendants of epiblast stem cells and possibly the primordial germ cells that persist into adulthood and undergo asymmetric cell division to replenish the gonadal germ cells throughout life. Elucidation of their role during infertility, endometrial repair, superovulation, and pathogenesis of various reproductive diseases like PCOS, endometriosis, cancer, and so on needs to be addressed. Hence, a detailed review of current understanding of VSEL biology is pertinent, which will hopefully open up new avenues for research to better understand various reproductive processes and cancers. It will also be relevant for future regenerative medicine, translational research, and clinical applications in human reproduction.

  12. Trypanosome species in neo-tropical bats: biological, evolutionary and epidemiological implications.

    PubMed

    Ramírez, Juan David; Tapia-Calle, Gabriela; Muñoz-Cruz, Geissler; Poveda, Cristina; Rendón, Lina M; Hincapié, Eduwin; Guhl, Felipe

    2014-03-01

    Bats (Chiroptera) are the only mammals naturally able to fly. Due to this characteristic they play a relevant ecological role in the niches they inhabit. These mammals spread infectious diseases from enzootic to domestic foci. Rabbies, SARS, fungi, ebola and trypanosomes are the most common pathogens these animals may host. We conducted intensive sampling of bats from the phyllostomidae, vespertilionidae and emballonuridae families in six localities from Casanare department in eastern Colombia. Blood-EDTA samples were obtained and subsequently submitted to analyses of mitochondrial and nuclear genetic markers in order to conduct barcoding analyses to discriminate trypanosome species. The findings according to the congruence of the three molecular markers suggest the occurrence of Trypanosoma cruzi cruzi (51%), T. c. marinkellei (9%), T. dionisii (13%), T. rangeli (21%), T. evansi (4%) and T. theileri (2%) among 107 positive bat specimens. Regarding the T. cruzi DTUs, we observed the presence of TcI (60%), TcII (15%), TcIII (7%), TcIV (7%) and TcBAT (11%) being the first evidence to our concern of the foreseen genotype TcBAT in Colombia. These results allowed us to propose reliable hypotheses regarding the ecology and biology of the bats circulating in the area including the enigmatic question whether TcBAT should be considered a novel DTU. The epidemiological and evolutionary implications of these findings are herein discussed.

  13. Very Small Embryonic-Like Stem Cells: Implications in Reproductive Biology

    PubMed Central

    Bhartiya, Deepa; Unni, Sreepoorna; Parte, Seema; Anand, Sandhya

    2013-01-01

    The most primitive germ cells in adult mammalian testis are the spermatogonial stem cells (SSCs) whereas primordial follicles (PFs) are considered the fundamental functional unit in ovary. However, this central dogma has recently been modified with the identification of a novel population of very small embryonic-like stem cells (VSELs) in the adult mammalian gonads. These stem cells are more primitive to SSCs and are also implicated during postnatal ovarian neo-oogenesis and primordial follicle assembly. VSELs are pluripotent in nature and characterized by nuclear Oct-4A, cell surface SSEA-4, and other pluripotent markers like Nanog, Sox2, and TERT. VSELs are considered to be the descendants of epiblast stem cells and possibly the primordial germ cells that persist into adulthood and undergo asymmetric cell division to replenish the gonadal germ cells throughout life. Elucidation of their role during infertility, endometrial repair, superovulation, and pathogenesis of various reproductive diseases like PCOS, endometriosis, cancer, and so on needs to be addressed. Hence, a detailed review of current understanding of VSEL biology is pertinent, which will hopefully open up new avenues for research to better understand various reproductive processes and cancers. It will also be relevant for future regenerative medicine, translational research, and clinical applications in human reproduction. PMID:23509758

  14. 'Biologizing' Psychopathy: Ethical, Legal, and Research Implications at the Interface of Epigenetics and Chronic Antisocial Conduct.

    PubMed

    Tamatea, Armon J

    2015-10-01

    Epigenetics, a field that links genetics and environmental influences on the expression of phenotypic traits, offers to increase our understanding of the development and trajectory of disease and psychological disorders beyond that thought of traditional genetic research and behavioural measures. By extension, this new perspective has implications for risk and risk management of antisocial behaviour where there is a biological component, such as psychopathy. Psychopathy is a personality disorder associated with repeat displays of antisocial behaviour, and is associated with the disproportionate imposition of harm on communities. Despite advances in our knowledge of psychopathic individuals, the construct remains complex and is hampered by a lack of integration across a range of fundamental domains. The clinical and forensic research on psychopathy is brought into conversation with the emerging field of epigenetics to highlight critical issues of (1) clinical definition and diagnosis, (2) assessment, (3) aetiology of psychopathic phenotypes, and (4) treatment and rehabilitation approaches. Broader ethical and legal questions of the role of epigenetic mechanisms in the management of psychopathy beyond the criminal justice arena are also outlined. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Biologic interactions between HSV-2 and HIV-1 and possible implications for HSV vaccine development.

    PubMed

    Schiffer, Joshua T; Gottlieb, Sami L

    2017-09-25

    Development of a safe and effective vaccine against herpes simplex virus type 2 (HSV-2) has the potential to limit the global burden of HSV-2 infection and disease, including genital ulcer disease and neonatal herpes, and is a global sexual and reproductive health priority. Another important potential benefit of an HSV-2 vaccine would be to decrease HIV infections, as HSV-2 increases the risk of HIV-1 acquisition several-fold. Acute and chronic HSV-2 infection creates ulcerations and draws dendritic cells and activated CD4+ T cells into genital mucosa. These cells are targets for HIV entry and replication. Prophylactic HSV-2 vaccines (to prevent infection) and therapeutic vaccines (to modify or treat existing infections) are currently under development. By preventing or modifying infection, an effective HSV-2 vaccine could limit HSV-associated genital mucosal inflammation and thus HIV risk. However, a vaccine might have competing effects on HIV risk depending on its mechanism of action and cell populations generated in the genital mucosa. In this article, we review biologic interactions between HSV-2 and HIV-1, consider HSV-2 vaccine development in the context of HIV risk, and discuss implications and research needs for future HSV vaccine development. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Biological reactivity of hypochlorous acid: implications for microbicidal mechanisms of leukocyte myeloperoxidase.

    PubMed Central

    Albrich, J M; McCarthy, C A; Hurst, J K

    1981-01-01

    Oxidative degradation of biological substrates by hypochlorous acid has been examined under reaction conditions similar to those found in active phagosomes. Iron sulfur proteins are bleached extremely rapidly, followed in decreasing order by beta-carotene, nucleotides, porphyrins, and heme proteins. Enzymes containing essential cysteine molecules are inactivated with an effectiveness that roughly parallels the nucleophilic reactivities of their sulfhydryl groups. Other compounds, including glucosamines, quinones, riboflavin, and, except for N-chlorination, phospholipids, are unreactive. Rapid irreversible oxidation of cytochromes, adenine nucleotides, and carotene pigments occurs when bacterial cells are exposed to exogenous hypochlorous acid; with Escherichia coli, titrimetric oxidation of cytochrome was found to coincide with loss of aerobic respiration. The occurrence of these cellular reactions implicates hypochlorous acid as a primary microbicide in myeloperoxidase-containing leukocytes; the reactivity patterns observed are consistent with the view that bactericidal action results primarily from loss of energy-linked respiration due to destruction of cellular electron transport chains and the adenine nucleotide pool. PMID:6264434

  17. Molecular biology of anal squamous cell carcinoma: implications for future research and clinical intervention.

    PubMed

    Bernardi, Maria-Pia; Ngan, Samuel Y; Michael, Michael; Lynch, A Craig; Heriot, Alexander G; Ramsay, Robert G; Phillips, Wayne A

    2015-12-01

    Anal squamous cell carcinoma is a human papillomavirus-related disease, in which no substantial advances in treatment have been made in over 40 years, especially for those patients who develop disease relapse and for whom no surgical options exist. HPV can evade the immune system and its role in disease progression can be exploited in novel immunotherapy platforms. Although several studies have investigated the expression and inactivation (through loss of heterozygosity) of tumour suppressor genes in the pathways to cancer, no clinically valuable biomarkers have emerged. Regulators of apoptosis, including survivin, and agents targeting the PI3K/AKT pathway, offer opportunities for targeted therapy, although robust data are scarce. Additionally, antibody therapy targeting EGFR may prove effective, although its safety profile in combination with standard chemoradiotherapy has proven to be suboptimal. Finally, progress in the treatment of anal cancer has remained stagnant due to a lack of preclinical models, including cell lines and mouse models. In this Review, we discuss the molecular biology of anal squamous cell carcinoma, clinical trials in progress, and implications for novel therapeutic targets. Future work should focus on preclinical models to provide a resource for investigation of new molecular pathways and for testing novel targets.

  18. The molecular biology of colorectal carcinoma and its implications: a review.

    PubMed

    Harrison, Sanjay; Benziger, Harrison

    2011-08-01

    Colorectal carcinoma is one of the most common cancers encountered in the western world and increasingly in the developing world as well. This conditions results in considerable morbidity and mortality. As a result of the impact colorectal carcinoma has on society, a considerable amount of research has gone into elucidating the molecular mechanisms of this disease. This has led to a proliferation in the understanding of the molecular aetiology of the disease. Such research has revealed the underlying mechanisms to be complex and diverse, with no single molecular cause for the development of colorectal cancer. In this review, we look at the basic underlying molecular mechanisms of colorectal cancer and also briefly explore its implications with regards to clinical applications. We look at how this information relates to the prognosis and also its potential use in screening. A medline and pubmed search was conducted using the keywords colorectal carcinoma, molecular biology of colorectal carcinoma, mutations, and the relevant articles were used for this review. Bibliographies of these articles were also searched for relevant articles. There is considerable information available on the pathogenesis of colorectal carcinoma and such knowledge is beginning to impact on clinical practice. Copyright © 2011 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  19. Attenuated Innate Immunity in Embryonic Stem Cells and Its Implications in Developmental Biology and Regenerative Medicine.

    PubMed

    Guo, Yan-Lin; Carmichael, Gordon G; Wang, Ruoxing; Hong, Xiaoxiao; Acharya, Dhiraj; Huang, Faqing; Bai, Fengwei

    2015-11-01

    Embryonic stem cells (ESCs) represent a promising cell source for regenerative medicine. Intensive research over the past 2 decades has led to the feasibility of using ESC-differentiated cells (ESC-DCs) in regenerative medicine. However, increasing evidence indicates that ESC-DCs generated by current differentiation methods may not have equivalent cellular functions to their in vivo counterparts. Recent studies have revealed that both human and mouse ESCs as well as some types of ESC-DCs lack or have attenuated innate immune responses to a wide range of infectious agents. These findings raise important concerns for their therapeutic applications since ESC-DCs, when implanted to a wound site of a patient, where they would likely be exposed to pathogens and inflammatory cytokines. Understanding whether an attenuated immune response is beneficial or harmful to the interaction between host and grafted cells becomes an important issue for ESC-based therapy. A substantial amount of recent evidence has demonstrated that the lack of innate antiviral responses is a common feature to ESCs and other types of pluripotent cells. This has led to the hypothesis that mammals may have adapted different antiviral mechanisms at different stages of organismal development. The underdeveloped innate immunity represents a unique and uncharacterized property of ESCs that may have important implications in developmental biology, immunology, and in regenerative medicine.

  20. Regulation of nuclear NF-κB oscillation by a diffusion coefficient and its biological implications.

    PubMed

    Ohshima, Daisuke; Ichikawa, Kazuhisa

    2014-01-01

    The transcription factor NF-κB shuttles between the cytoplasm and the nucleus, and nuclear NF-κB is known to oscillate with a cycle of 1.5-2.5 h following the application of external stimuli. Oscillation pattern of NF-κB is implicated in regulation of the gene expression profile. In a previous report, we found that the oscillation pattern of nuclear NF-κB in a computational 3D spherical cell was regulated by spatial parameters such as nuclear to cytoplasmic volume ratio, nuclear transport, locus of protein synthesis, and diffusion coefficient. Here we report analyses and a biological implication for the regulation of oscillation pattern by diffusion coefficient. Our analyses show that the "reset" of nuclear NF-κB, defined as the return of nuclear NF-κB to the initial level or lower, was crucial for the oscillation; this was confirmed by the flux analysis. In addition, we found that the distant cytoplasmic location from the nucleus acted as a "reservoir" for storing newly synthesized IκBα. When the diffusion coefficient of proteins was large (≥ 10-11 m2/s), a larger amount of IκBα was stored in the "reservoir" with a large flux by diffusion. Subsequently, stored IκBα diffused back to the nucleus, where nuclear NF-κB was "reset" to the initial state. This initiated the next oscillation cycle. When the diffusion coefficient was small (≤ 10-13 m2/s), oscillation of nuclear NF-κB was not observed because a smaller amount of IκBα was stored in the "reservoir" and there was incomplete "reset" of nuclear NF-κB. If the diffusion coefficient for IκBα was increased to 10-11 m2/s keeping other proteins at 10-13 m2/s, the oscillation was rescued confirming the "reset" and "reservoir" hypothesis. Finally, we showed altered effective value of diffusion coefficient by diffusion obstacles. Thus, organelle crowding seen in stressed cells possibly changes the oscillation pattern by controlling the effective diffusion coefficient.

  1. Observing and diagnosing biological fluxes and canopy mechanisms with implications for climate change and ecosystem disturbance

    NASA Astrophysics Data System (ADS)

    Reed, David E.

    Improving our predictions of ecosystem responses is an important challenge in ecological science due to the increasing number of stresses applied to biological systems. The assumption that ecosystems are operating in steady-state conditions at annual and longer time scales is far too simple of a model as ecosystems are an integral part of the earth system. Anthropogenic and non-anthropogenic forces acting on ecosystems within the earth system are numerous and include broad external factors such as climate change to specific internal factors such as infestations causing disturbance. This research quantifies changes in biogeochemical cycling and increases understanding of the mechanisms that control these cycles across two major ecosystems of the intermountain west with the broad goal of better predictive power of ecosystem responses. Eddy covariance methods were used to quantify carbon, water and energy fluxes at two different field sites in sagebrush ecosystems and one field site in a lodgepole pine ecosystem, in south-east Wyoming and northern Colorado. These measurements were supported with environmental and micrometeorological measurements in order to better understand physical mechanisms and canopy processes that control these biological fluxes. Results from the sagebrush component of this dissertation show how semi-arid sagebrush canopies interact with the lower atmosphere in ways that can alter environmental control of water loss with changing leaf area. This feedback has large implications combined with the large land area of these ecosystems and predictions of a dryer and more variable precipitation regime in the future. At the higher elevation lodgepole pine site, the ecosystem is undergoing a major mortality disturbance due to native bark beetles. Interestingly, even with ˜80% mortality of the canopy, few changes are observed to carbon and water cycling, as well as water use efficiency and energy cycling at the ecosystem scale. This calls into question

  2. Absorption of millimeter waves by human beings and its biological implications

    SciTech Connect

    Gandhi, O.P.; Riazi, A.

    1986-02-01

    With recent advances in millimeter-wave technology, including the availability of high-power sources, in this band, it has become necessary to understand the biological implications of this energy for human beings. This paper gives the millimeter-wave absorption efficiency for the human body with and without clothing. Ninety to ninety-five percent of the incident energy may be absorbed in the skin with dry clothing, with or without an intervening air gap, acting as an impedance transformer. On account of the submillimeter depths of penetration in the skin, superficial SAR's as high as 65-357 W/Kg have been calculated for power density of incident radiation corresponding to the ANSI guideline of 5 mW/cm/sup 2/. Because most of the millimeter-wave absorption is in the region of the cutaneous thermal receptors (0.1-1.0 mm), the sensations of absorbed energy are likely to be similar to those of IR. For the latter, threshold of heat perception is near 0.67 mW/cm/sup 2/, with power densities on the order of 8.7 mW/cm/sup 2/ likely to cause sensations of ''very warm to hot'' with a latency of 1.0 +- 0.6 s. Calculations are made for thresholds of hearing of pulsed millimeter waves. Pulsed energy densities of 143/579 ..mu..J/cm/sup 2/ are obtained for the frequency band 30-300 GHz. These are 8-28 times larger than the threshold for microwaves below 3 GHz. The paper also points to the need for evaluation of ocular effects of millimeter-wave irradiation because of high SAR's in the cornea.

  3. Selected physical, biological and biogeochemical implications of a rapidly changing Arctic Marginal Ice Zone

    NASA Astrophysics Data System (ADS)

    Barber, David G.; Hop, Haakon; Mundy, Christopher J.; Else, Brent; Dmitrenko, Igor A.; Tremblay, Jean-Eric; Ehn, Jens K.; Assmy, Philipp; Daase, Malin; Candlish, Lauren M.; Rysgaard, Søren

    2015-12-01

    The Marginal Ice Zone (MIZ) of the Arctic Ocean is changing rapidly due to a warming Arctic climate with commensurate reductions in sea ice extent and thickness. This Pan-Arctic review summarizes the main changes in the Arctic ocean-sea ice-atmosphere (OSA) interface, with implications for primary- and secondary producers in the ice and the underlying water column. Changes in the Arctic MIZ were interpreted for the period 1979-2010, based on best-fit regressions for each month. Trends of increasingly open water were statistically significant for each month, with quadratic fit for August-November, illustrating particularly strong seasonal feedbacks in sea-ice formation and decay. Geographic interpretations of physical and biological changes were based on comparison of regions with significant changes in sea ice: (1) The Pacific Sector of the Arctic Ocean including the Canada Basin and the Beaufort, Chukchi and East Siberian seas; (2) The Canadian Arctic Archipelago; (3) Baffin Bay and Hudson Bay; and (4) the Barents and Kara seas. Changes in ice conditions in the Barents sea/Kara sea region appear to be primarily forced by ocean heat fluxes during winter, whereas changes in the other sectors appear to be more summer-autumn related and primarily atmospherically forced. Effects of seasonal and regional changes in OSA-system with regard to increased open water were summarized for photosynthetically available radiation, nutrient delivery to the euphotic zone, primary production of ice algae and phytoplankton, ice-associated fauna and zooplankton, and gas exchange of CO2. Changes in the physical factors varied amongst regions, and showed direct effects on organisms linked to sea ice. Zooplankton species appear to be more flexible and likely able to adapt to variability in the onset of primary production. The major changes identified for the ice-associated ecosystem are with regard to production timing and abundance or biomass of ice flora and fauna, which are related to

  4. Reductive activation of mitomycin C by thiols: kinetics, mechanism, and biological implications.

    PubMed

    Paz, Manuel M

    2009-10-01

    The clinically used antitumor antibiotic mitomycin C requires a reductive activation to be converted to a bis-electrophile that forms several covalent adducts with DNA, including an interstrand cross-link which is considered to be the lesion responsible for the cytotoxic effects of the drug. Enzymes such as cytochrome P450 reductase and DT-diaphorase have traditionally been implicated in the bioreduction of mitomycin C, but recent reports indicate that enzymes containing a dithiol active site are also involved in the metabolism of mitomycin C. The reductive activation can also be effected in vitro with chemical reductants, but until now, mitomycin C was considered to be inert to thiols. We report here that mitomycin C can, in fact, be reductively activated by thiols. We show that the reaction is autocatalytic and that the end product is a relatively stable aziridinomitosene that can be trapped by adding several nucleophiles after the activation reaction. Kinetic studies show that the reaction is highly sensitive to pH and does not proceed or proceeds very slowly at neutral pH, an observation that explains the unsuccessful results on previous attempts to activate mitomycin C with thiols. The optimum pH for the reactions is around the pK(a) values of the thiols used in the activation. A mechanism for the reaction is hypothesized, involving the initial formation of a thiolate-mitomycin adduct, that then evolves to give the hydroquinone of mitomycin C and disulfide. The results presented here provide a chemical mechanism to explain how some biological dithiols containing an unusually acidic thiol group (deprotonated at physiological pH) participate in the modulation of mitomycin C cytotoxicity.

  5. Characterization of RON protein isoforms in pancreatic cancer: implications for biology and therapeutics.

    PubMed

    Chakedis, Jeffery; French, Randall; Babicky, Michele; Jaquish, Dawn; Mose, Evangeline; Cheng, Peter; Holman, Patrick; Howard, Haleigh; Miyamoto, Jaclyn; Porras, Paula; Walterscheid, Zakk; Schultz-Fademrecht, Carsten; Esdar, Christina; Schadt, Oliver; Eickhoff, Jan; Lowy, Andrew M

    2016-07-19

    The RON tyrosine kinase receptor is under investigation as a novel target in pancreatic cancer. While RON mutations are uncommon, RON isoforms are produced in cancer cells via a variety of mechanisms. In this study we sought to: 1) characterize RON isoform expression in pancreatic cancer, 2) investigate mechanisms that regulate isoform expression, and 3) determine how various isoforms effect gene expression, oncogenic phenotypes and responses to RON directed therapies. We quantified RON transcripts in human pancreatic cancer and found expression levels 2500 fold that of normal pancreas with RON isoform expression comprising nearly 50% of total transcript. RNA seq studies revealed that the short form (sfRON) and P5P6 isoforms which have ligand independent activity, induce markedly different patterns of gene expression than wild type RON. We found that transcription of RON isoforms is regulated by promoter hypermethylation as the DNA demethylating agent 5-aza-2'-deoxycytidine decreased all RON transcripts in a subset of pancreatic cancer cell lines. The viability of sfRON-expressing HPDE cells was reduced by a RON specific small molecule inhibitor, while a therapeutic monoclonal antibody had no demonstrable effects. In summary, RON isoforms may comprise half of total RON transcript in human pancreatic cancer and their expression is regulated at least in part by promoter hypermethylation. RON isoforms activate distinct patterns of gene expression, have transforming activity and differential responses to RON directed therapies. These findings further our understanding of RON biology in pancreatic cancer and have implications for therapeutic strategies to target RON activity.

  6. Peroxisome proliferator-activated receptors in vascular biology-molecular mechanisms and clinical implications.

    PubMed

    Touyz, Rhian M; Schiffrin, Ernesto L

    2006-07-01

    Peroxisome proliferator-activated receptors (PPAR)alpha, gamma and beta/delta belong to the nuclear receptor family of ligand-activated transcription factors. PPARs heterodimerize with the retinoid X receptor (RXR) and then act as transcription factors to modulate the function of many target genes. PPARalpha, gamma and beta/delta subtypes have significant differences in their ligand and gene specificities. PPARalpha is activated by polyunsaturated fatty acids and by fibrate drugs (fenofibrate and gemfibrozil) and controls expression of genes involved in lipid metabolism. PPARgamma is activated by fatty acid derivatives, such as hydroxyoctadecadienoic acid (HODEs), prostaglandin derivatives, such as 15-deoxy-Delta12,14-prostaglandin J2, and thiazolidinedione (glitazone) drugs, such as pioglitazone and rosiglitazone. PPARgamma is a key regulator of glucose homeostasis and adipogenesis. PPARbeta/delta ligands include polyunsaturated fatty acids, prostaglandins and synthetic compounds and stimulate fatty acid oxidation. All PPARs are expressed in vascular cells where they exert antiatherogenic, anti-inflammatory and vasculoprotective actions. Activators of PPARalpha (fibrates) and PPARgamma (thiazolidinediones or glitazones) antagonize angiotensin II effects in vivo and in vitro and have cardiovascular antioxidant and anti-inflammatory actions. PPAR agonists slightly reduce blood pressure are cardio-protective and correct vascular structure and endothelial dysfunction in experimental models of hypertension. Because of these beneficial effects, activators of PPARs may have therapeutic potential in the prevention of cardiovascular disease beyond their actions on carbohydrate and lipid metabolism. The present chapter focuses on the role of PPARs in vascular biology and discusses the clinical implications of using PPAR agonists in the management of vascular disease.

  7. Ti(IV) and the Siderophore Desferrioxamine B: A Tight Complex Has Biological and Environmental Implications.

    PubMed

    Jones, Kayleigh E; Batchler, Kathleen L; Zalouk, Célia; Valentine, Ann M

    2017-02-06

    The siderophore desferrioxamine B (DFOB) binds Ti(IV) tightly and precludes its hydrolytic precipitation under biologically and environmentally relevant conditions. This interaction of DFOB with Ti(IV) is investigated by using spectro-potentiometric and spectro-photometric titrations, mass spectrometry, isothermal titration calorimetry (ITC), and computational modeling. The data from pH 2-10 suggest two one-proton equilibria among three species, with one species predominating below pH 3.5, a second from pH 3.5 to 8, and a third above pH 8. The latter species is prone to slow hydrolytic precipitation. Electrospray mass spectrometry allowed the detection of [Ti(IV) (HDFOB)](2+) and [Ti(DFOB)](+); these species were assigned as the pH < 3.5 and the 3.5 < pH < 8 species, respectively. The stability constant for Ti(IV)-DFOB was determined by using UV/vis-monitored competition with ethylenediaminetetraacetic acid (EDTA). Taking into consideration the available binding constant of Ti(IV) and EDTA, the data reveal values of log β111 = 41.7, log β110 = 38.1, and log β11-1 = 30.1. The former value was supported by ITC, with the transfer of Ti(IV) from EDTA to DFOB determined to be both enthalpically and entropically favorable. Computational methods yielded a model of Ti-DFOB. The physiological and environmental implications of this tight interaction and the potential role of DFOB in solubilizing Ti(IV) are discussed.

  8. Characterization of RON protein isoforms in pancreatic cancer: implications for biology and therapeutics

    PubMed Central

    Chakedis, Jeffery; French, Randall; Babicky, Michele; Jaquish, Dawn; Mose, Evangeline; Cheng, Peter; Holman, Patrick; Howard, Haleigh; Miyamoto, Jaclyn; Porras, Paula; Walterscheid, Zakk; Schultz-Fademrecht, Carsten; Esdar, Christina; Schadt, Oliver; Eickhoff, Jan; Lowy, Andrew M.

    2016-01-01

    The RON tyrosine kinase receptor is under investigation as a novel target in pancreatic cancer. While RON mutations are uncommon, RON isoforms are produced in cancer cells via a variety of mechanisms. In this study we sought to: 1) characterize RON isoform expression in pancreatic cancer, 2) investigate mechanisms that regulate isoform expression, and 3) determine how various isoforms effect gene expression, oncogenic phenotypes and responses to RON directed therapies. We quantified RON transcripts in human pancreatic cancer and found expression levels 2500 fold that of normal pancreas with RON isoform expression comprising nearly 50% of total transcript. RNA seq studies revealed that the short form (sfRON) and P5P6 isoforms which have ligand independent activity, induce markedly different patterns of gene expression than wild type RON. We found that transcription of RON isoforms is regulated by promoter hypermethylation as the DNA demethylating agent 5-aza-2′-deoxycytidine decreased all RON transcripts in a subset of pancreatic cancer cell lines. The viability of sfRON-expressing HPDE cells was reduced by a RON specific small molecule inhibitor, while a therapeutic monoclonal antibody had no demonstrable effects. In summary, RON isoforms may comprise half of total RON transcript in human pancreatic cancer and their expression is regulated at least in part by promoter hypermethylation. RON isoforms activate distinct patterns of gene expression, have transforming activity and differential responses to RON directed therapies. These findings further our understanding of RON biology in pancreatic cancer and have implications for therapeutic strategies to target RON activity. PMID:27323855

  9. Diverse Basis of β-Catenin Activation in Human Hepatocellular Carcinoma: Implications in Biology and Prognosis

    PubMed Central

    Okabe, Hirohisa; Kinoshita, Hiroki; Imai, Katsunori; Nakagawa, Shigeki; Higashi, Takaaki; Arima, Kota; Uchiyama, Hideaki; Ikegami, Toru; Harimoto, Norifumi; Itoh, Shinji; Ishiko, Takatoshi; Yoshizumi, Tomoharu; Beppu, Toru; Monga, Satdarshan P. S.; Baba, Hideo; Maehara, Yoshihiko

    2016-01-01

    Aim β-catenin signaling is a major oncogenic pathway in hepatocellular carcinoma (HCC). Since β-catenin phosphorylation by glycogen synthase kinase 3β (GSK3β) and casein kinase 1ε (CK1ε) results in its degradation, mutations affecting these phosphorylation sites cause β-catenin stabilization. However, the relevance of missense mutations in non-phosphorylation sites in exon 3 remains unclear. The current study explores significance of such mutations in addition to addressing the clinical and biological implications of β-catenin activation in human HCC. Methods Gene alteration in exon3 of CTNNB1, gene expression of β-catenin targets such as glutamate synthetase (GS), axin2, lect2 and regucalcin (RGN), and protein expression of β-catenin were examined in 125 human HCC tissues. Results Sixteen patients (12.8%) showed conventional missense mutations affecting codons 33, 37, 41, and 45. Fifteen additional patients (12.0%) had other missense mutations in codon 32, 34, and 35. Induction of exon3 mutation caused described β-catenin target gene upregulation in HCC cell line. Interestingly, conventional and non-phosphorylation site mutations were equally associated with upregulation of β-catenin target genes. Nuclear localization of β-catenin was associated with poor overall survival (p = 0.0461). Of these patients with nuclear β-catenin localization, loss of described β-catenin target gene upregulation showed significant poorer overall survival than others (p = 0.0001). Conclusion This study suggests that both conventional and other missense mutations in exon 3 of CTNNB1 lead to β-catenin activation in human HCC. Additionally, the mechanism of nuclear β-catenin localization without upregulation of described β-catenin target genes might be of clinical importance depending on distinct mechanism. PMID:27100093

  10. Rapid CO2 permeation across biological membranes: implications for CO2 venting from tissue.

    PubMed

    Hulikova, Alzbeta; Swietach, Pawel

    2014-07-01

    The degree to which cell membranes are barriers to CO2 transport remains controversial. Proteins, such as aquaporins and Rh complex, have been proposed to facilitate CO2 transport, implying that the nonchannel component of membranes must have greatly reduced CO2 permeability. To determine whether membrane CO2 permeation is rate limiting for gas transport, the spread of CO2 across multicellular tissue growths (spheroids) was measured using intracellular pH as a spatial readout. Colorectal HCT116 cells have basal water and NH3 permeability, indicating the functional absence of aquaporins and gas channels. However, CO2 diffusivity in HCT116 spheroids was only 24 ± 4% lower than in pure water, which can be accounted for fully by volume exclusion due to proteins. Diffusivity was unaffected by blockers of aquaporins and Rh complex (Hg(2+), p-chloromercuribenzoic acid, and 4,4'-diisothiocyano-2,2'-stilbene-disulfonic acid) but decreased under hypertonic conditions (by addition of 300 mOsm mannitol), which increases intracellular protein crowding. Similar CO2 diffusivity was measured in spheroids of T47D breast cells (basal water permeability) and NHDF-Ad fibroblasts (aquaporin-facilitated water permeability). In contrast, diffusivity of NH3, a smaller but less lipophilic gas, was considerably slower than in pure water, as expected from rate-limiting membrane permeation. In conclusion, membranes, even in the functional absence of proposed gas channels, do not restrict CO2 venting from tissue growths.-Hulikova, A., Swietach, P. Rapid CO2 permeation across biological membranes: implications for CO2 venting from tissue.

  11. Seed preferences by rodents in the agri-environment and implications for biological weed control.

    PubMed

    Fischer, Christina; Türke, Manfred

    2016-08-01

    Post-dispersal seed predation and endozoochorous seed dispersal are two antagonistic processes in relation to plant recruitment, but rely on similar preconditions such as feeding behavior of seed consumers and seed traits. In agricultural landscapes, rodents are considered important seed predators, thereby potentially providing regulating ecosystem services in terms of biological weed control. However, their potential to disperse seeds endozoochorously is largely unknown. We exposed seeds of arable plant species with different seed traits (seed weight, nutrient content) and different Red List status in an experimental rye field and assessed seed removal by rodents. In a complementary laboratory experiment, consumption rates, feeding preferences, and potential endozoochory by two vole species (Microtus arvalis and Myodes glareolus) were tested. Seed consumption by rodents after 24 h was 35% in the field and 90% in the laboratory. Both vole species preferred nutrient-rich over nutrient-poor seeds and M. glareolus further preferred light over heavy seeds and seeds of common over those of endangered plants. Endozoochory by voles could be neglected for all tested plant species as no seeds germinated, and only few intact seeds could be retrieved from feces. Synthesis and applications. Our results suggest that voles can provide regulating services in agricultural landscapes by depleting the seed shadow of weeds, rather than facilitating plant recruitment by endozoochory. In the laboratory, endangered arable plants were less preferred by voles than noxious weeds, and thus, our results provide implications for seed choice in restoration approaches. However, other factors such as seed and predator densities need to be taken into account to reliably predict the impact of rodents on the seed fate of arable plants.

  12. Assessment of temporal variance components and implications for trend assessment in biological monitoring programs

    EPA Science Inventory

    Assessment of temporal trends in biological monitoring programs is often undertaken without an understanding of temporal variability of biological communities. Typically, the within-site variance is unknown and included as part of sampling error. This investigation – designed jo...

  13. Assessment of temporal variance components and implications for trend assessment in biological monitoring programs

    EPA Science Inventory

    Assessment of temporal trends in biological monitoring programs is often undertaken without an understanding of temporal variability of biological communities. Typically, the within-site variance is unknown and included as part of sampling error. This investigation – designed jo...

  14. Climate matching: implications for the biological control of hemlock woolly adelgid

    Treesearch

    R. Talbot III. Trotter

    2008-01-01

    Classical biological control programs are faced with a daunting challenge: inserting a new species into an existing ecological system. In order for the newly introduced biological control species to survive and reproduce, the recipient ecosystem must provide the required biotic and abiotic requirements. The Adelgid Biological Control simulator (ABCs), a simulation...

  15. Biological products for the treatment of psoriasis: therapeutic targets, pharmacodynamics and disease-drug-drug interaction implications.

    PubMed

    Wang, Jie; Wang, Yow-Ming C; Ahn, Hae-Young

    2014-09-01

    Psoriasis is a chronic inflammatory skin disease condition that involves altered expression of a broad spectrum of proinflammatory cytokines which are associated with activation of T cells and proliferation of keratinocytes. Currently approved biological products for psoriasis treatment fall into two main classes: cytokine modulators and biologics targeting T cells. In psoriatic patients, elevated levels of proinflammatory cytokines are observed. Elevated proinflammatory cytokines can suppress some cytochrome P450 (CYP) enzymes, and the treatment of psoriasis with biological products can reduce proinflammatory cytokine levels. Therefore, the exposure of CYP substrate drugs is anticipated to be affected by the psoriasis disease resulting in a higher exposure than in healthy state (named disease-drug interaction) as well as by the biological treatments due to disease improvements resulting in a decrease in exposure (named disease-drug-drug interaction, disease-DDI). However, the quantitative impact on CYP substrate exposure due to disease or due to treatment with biological products remains to be evaluated. The objective of the current review is to provide an overview of the therapeutic targets and cytokine-related pharmacodynamic effects of biological products in psoriasis treatment with a particular focus on their implications for disease-DDI. The clinical study design considerations for psoriasis disease-DDI evaluation are also discussed.

  16. Initial Test Firing Results for Solid CO/GOX Cryogenic Hybrid Rocket Engine for Mars ISRU Propulsion Applications

    NASA Technical Reports Server (NTRS)

    Rice, Eric E.; St. Clair, Christopher P.; Chiaverini, Martin J.; Knuth, William H.; Gustafson, Robert J.; Gramer, Daniel J.

    1999-01-01

    ORBITEC is developing methods for producing, testing, and utilizing Mars-based ISRU fuel/oxidizer combinations to support low cost, planetary surface and flight propulsion and power systems. When humans explore Mars we will need to use in situ resources that are available, such as: energy (solar); gases or liquids for life support, ground transportation, and flight to and from other surface locations and Earth; and materials for shielding and building habitats and infrastructure. Probably the easiest use of Martian resources to reduce the cost of human exploration activities is the use of the carbon and oxygen readily available from the CO2 in the Mars atmosphere. ORBITEC has conducted preliminary R&D that will eventually allow us to reliably use these resources. ORBITEC is focusing on the innovative use of solid CO as a fuel. A new advanced cryogenic hybrid rocket propulsion system is suggested that will offer advantages over LCO/LOX propulsion, making it the best option for a Mars sample return vehicle and other flight vehicles. This technology could also greatly support logistics and base operations by providing a reliable and simple way to store solar or nuclear generated energy in the form of chemical energy that can be used for ground transportation (rovers/land vehicles) and planetary surface power generators. This paper describes the overall concept and the test results of the first ever solid carbon monoxide/oxygen rocket engine firing.

  17. Initial Test Firing Results for Solid CO/GOX Cryogenic Hybrid Rocket Engine for Mars ISRU Propulsion Applications

    NASA Technical Reports Server (NTRS)

    Rice, Eric E.; St. Clair, Christopher P.; Chiaverini, Martin J.; Knuth, William H.; Gustafson, Robert J.; Gramer, Daniel J.

    1999-01-01

    ORBITEC is developing methods for producing, testing, and utilizing Mars-based ISRU fuel/oxidizer combinations to support low cost, planetary surface and flight propulsion and power systems. When humans explore Mars we will need to use in situ resources that are available, such as: energy (solar); gases or liquids for life support, ground transportation, and flight to and from other surface locations and Earth; and materials for shielding and building habitats and infrastructure. Probably the easiest use of Martian resources to reduce the cost of human exploration activities is the use of the carbon and oxygen readily available from the CO2 in the Mars atmosphere. ORBITEC has conducted preliminary R&D that will eventually allow us to reliably use these resources. ORBITEC is focusing on the innovative use of solid CO as a fuel. A new advanced cryogenic hybrid rocket propulsion system is suggested that will offer advantages over LCO/LOX propulsion, making it the best option for a Mars sample return vehicle and other flight vehicles. This technology could also greatly support logistics and base operations by providing a reliable and simple way to store solar or nuclear generated energy in the form of chemical energy that can be used for ground transportation (rovers/land vehicles) and planetary surface power generators. This paper describes the overall concept and the test results of the first ever solid carbon monoxide/oxygen rocket engine firing.

  18. Strengthening the biological weapons convention and implications on the pharmaceutical and biotechnology industry.

    PubMed

    Zabriskie, D

    1998-06-01

    The development, production, stockpiling, and use of biological weapons are banned by the 1972 Biological Weapons Convention (BWC). Reflecting the realities of the Cold War era in which it was negotiated, the BWC lacks means for compliance verification or enforcement. International efforts to remedy this deficiency are accelerating in the face of evidence that covert biological weapon programs are proliferating at the national and subnational levels.

  19. Alex Comfort's biology of ontology: implications for gerontology, phenomenology and the philosophy of science.

    PubMed

    Wheeler, H

    1998-01-01

    Alex Comfort's explorations into the biology of the human experiences of self-consciousness and the Oceanic opened avenues of investigation and speculation that deserve reconsideration. His work on the biology of ontology remains valuable, and especially noteworthy is his challenge to make such approaches the basis for a new paradigm of science.

  20. "McLean v. Arkansas" (1982) and Beyond: Implications for Biology Professors

    ERIC Educational Resources Information Center

    Bland, Mark W.; Moore, Randy

    2011-01-01

    To assess current trends of evolution instruction in high schools of the mid-South, we invited Arkansas high school biology teachers from across the state to respond to a survey designed to address this issue. We also asked students enrolled in a freshman-level, nonmajors biology course at a midsize public Arkansas university to recall their…

  1. Population biology of the forest pathogen Heterbasidion annosum:implications for forest management

    Treesearch

    M. Garbelotto; W.J. Otrosina; F.W. Cobb; T.D. Bruns

    1998-01-01

    Heterobasidion annosumranks as one of the most destructive pathogens in North American coniferous forests. Understanding the popula­tion biology of this fungus may facilitate un­derstanding not only the basic biology of the organism, but also the general patterns of disease development,...

  2. "McLean v. Arkansas" (1982) and Beyond: Implications for Biology Professors

    ERIC Educational Resources Information Center

    Bland, Mark W.; Moore, Randy

    2011-01-01

    To assess current trends of evolution instruction in high schools of the mid-South, we invited Arkansas high school biology teachers from across the state to respond to a survey designed to address this issue. We also asked students enrolled in a freshman-level, nonmajors biology course at a midsize public Arkansas university to recall their…

  3. Synthetic biology in space: considering the broad societal and ethical implications

    NASA Astrophysics Data System (ADS)

    Race, Margaret S.; Moses, Jacob; McKay, Christopher; Venkateswaran, Kasthuri J.

    2012-02-01

    Although the field of synthetic biology is still in its infancy, there are expectations for great advances in the coming decades, both on Earth and potentially in space. Promising applications for long duration space missions include a variety of biologically engineered products and biologically aided processes and technologies, which will undoubtedly be scrutinized for risks and benefits in the broad context of ethical, legal and social realms. By comparing and contrasting features of Earth-based and space-applied synthetic biology, it is possible to identify the likely similarities and differences, and to identify possible challenges ahead for space applications that will require additional research, both in the short and long terms. Using an analytical framework associated with synthetic biology and new technologies on Earth, this paper analyses the kinds of issues and concerns ahead, and identifies those areas where space applications may require additional examination. In general, while Earth- and space-based synthetic biology share many commonalities, space applications have additional challenges such as those raised by space microbiology and environmental factors, legal complications, planetary protection, lack of decision-making infrastructure(s), long duration human missions, terraforming and the possible discovery of extraterrestrial (ET) life. For synthetic biology, the way forward offers many exciting opportunities, but is not without legitimate concerns - for life, environments and society, both on Earth and beyond.

  4. Trends in American agriculture. Their implications for biological warfare against crop and animal resources.

    PubMed

    Deen, W A

    1999-01-01

    Current trends in American agriculture have changed the vulnerability to use of biological weapons against plant and animal resources. The major effect has been a requirement to look again at the model of the U.S. BW program of widespread dissemination of agent and look to attack models requiring much lower levels of resources. The U.S. biological warfare program models must take the effects of these major trends into account when considering the possible widespread dissemination of a biological agent. The models must also acknowledge the lowered levels or resources required to make such attacks given the modern trends in American agriculture.

  5. Biological Contributions to Addictions in Adolescents and Adults: Prevention, Treatment and Policy Implications

    PubMed Central

    Potenza, Marc N.

    2012-01-01

    Purpose Despite significant advances in our understanding of the biological bases of addictions, these disorders continue to represent a huge public health burden that is associated with substantial personal suffering. Efforts to target addictions require consideration of how the improved biological understanding of addictions may lead to improved prevention, treatment and policy initiatives. Method In this article, we provide a narrative review of current biological models for addictions with a goal of placing existing data and theories within a translational and developmental framework targeting the advancement of prevention, treatment and policy strategies. Results Data regarding individual differences, intermediary phenotypes, and main and interactive influences of genetic and environmental contributions in the setting of developmental trajectories that may be influenced by addictive drugs or behavior indicate complex underpinnings of addictions. Conclusions Consideration and further elucidation of the biological etiologies of addictions hold significant potential for making important gains and reducing the public health impact of addictions. PMID:23332567

  6. Implications of paper vs stainless steel biological indicator substrates for formaldehyde gas decontamination.

    PubMed

    Gordon, D; Madden, B; Krishnan, J; Klassen, S; Dalmasso, J; Theriault, S

    2011-02-01

    This study was undertaken to determine the effectiveness of biological indicators currently being employed during formaldehyde decontamination. Data suggest that detectable amounts of formaldehyde are absorbed into the paper strips contained in currently used biological indicators. Absorbed formaldehyde has the potential to inhibit the growth of indicator spores, thus leading to false negative results. Indicators composed of either stainless steel carriers or paper strips were investigated to determine whether stainless steel carriers can be used as an alternative to paper strip indicators. Biological indicators were exposed to formaldehyde gas and were tested for the presence of formaldehyde and any possible inhibition of spore growth. Absorbed formaldehyde was detected in the paper strip carriers while no formaldehyde was detected from any of the stainless steel carriers. Exposed paper strips were found to inhibit growth of up to 1 × 10(6) spores while the stainless steel carriers did not inhibit the growth of spores. During decontamination, biological indicators composed of paper spore strips absorb formaldehyde and inhibit growth of any surviving spores. Stainless steel carriers do not absorb formaldehyde and are an ideal alternative substrate for biological indicators. The popular paper strip biological indicator can lead to false negative results during decontamination and is unsuitable for validating formaldehyde decontamination. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

  7. The emerging role of reactive oxygen and nitrogen species in redox biology and some implications for plasma applications to medicine and biology

    NASA Astrophysics Data System (ADS)

    Graves, David B.

    2012-07-01

    Reactive oxygen species (ROS) and the closely related reactive nitrogen species (RNS) are often generated in applications of atmospheric pressure plasmas intended for biomedical purposes. These species are also central players in what is sometimes referred to as ‘redox’ or oxidation-reduction biology. Oxidation-reduction biochemistry is fundamental to all of aerobic biology. ROS and RNS are perhaps best known as disease-associated agents, implicated in diabetes, cancer, heart and lung disease, autoimmune disease and a host of other maladies including ageing and various infectious diseases. These species are also known to play active roles in the immune systems of both animals and plants and are key signalling molecules, among many other important roles. Indeed, the latest research has shown that ROS/RNS play a much more complex and nuanced role in health and ageing than previously thought. Some of the most potentially profound therapeutic roles played by ROS and RNS in various medical interventions have emerged only in the last several years. Recent research suggests that ROS/RNS are significant and perhaps even central actors in the actions of antimicrobial and anti-parasite drugs, cancer therapies, wound healing therapies and therapies involving the cardiovascular system. Understanding the ways ROS/RNS act in established therapies may help guide future efforts in exploiting novel plasma medical therapies. The importance of ROS and RNS to plant biology has been relatively little appreciated in the plasma biomedicine community, but these species are just as important in plants. It appears that there are opportunities for useful applications of plasmas in this area as well.

  8. Mauna Kea, Hawaii as an Analogue Site for Future Planetary Resource Exploration: Results from the 2010 ILSO-ISRU Field-Testing Campaign

    NASA Technical Reports Server (NTRS)

    ten Kate, I. L.; Armstrong, R.; Bernhardt, B.; Blummers, M.; Boucher, D.; Caillibot, E.; Captain, J.; Deleuterio, G.; Farmer, J. D.; Glavin, D. P.; Hamilton, J. C.; Klingelhoefer, G.; Morris, R. V.; Nunez, J. I.; Quinn, J. W.; Sanders, G. B.; Sellar, R. G.; Sigurdson, L.; Taylor, R.; Zacny, K.

    2010-01-01

    Within the framework of the International Lunar Surface Operation - In-Situ Resource Utilization Analogue Test held on January 27 - February 11, 2010 on the Mauna Kea volcano in Hawaii, a number of scientific instrument teams collaborated to characterize the field site and test instrument capabilities outside laboratory environments. In this paper, we provide a geological setting for this new field-test site, a description of the instruments that were tested during the 2010 ILSO-ISRU field campaign, and a short discussion for each instrument about the validity and use of the results obtained during the test. These results will form a catalogue that may serve as reference for future test campaigns. In this paper we provide a description and regional geological setting for a new field analogue test site for lunar resource exploration, and discuss results obtained from the 2010 ILSO-ISRU field campaign as a reference for future field-testing at this site. The following instruments were tested: a multispectral microscopic imager, MMI, a Mossbauer spectrometer, an evolved gas analyzer, VAPoR, and an oxygen and volatile extractor called RESOLVE. Preliminary results show that the sediments change from dry, organic-poor, poorly-sorted volcaniclastic sand on the surface, containing basalt, iron oxides and clays, to more water- and organic-rich, fine grained, well-sorted volcaniclastic sand, primarily consisting of iron oxides and depleted of basalt and clays. Furthermore, drilling experiments showed a very close correlation between drilling on the Moon and drilling at the test site. The ILSO-ISRU test site was an ideal location for testing strategies for in situ resource exploration at the lunar or martian surface.

  9. Development of an Electrostatic Precipitator to Remove Martian Atmospheric Dust from ISRU Gas Intakes During Planetary Exploration Missions

    NASA Technical Reports Server (NTRS)

    Clements, J. Sidney; Thompson, Samuel M.; Cox, Nathan D.; Johansen, Michael R.; Williams, Blakeley S.; Hogue, Michael D.; Lowder, M. Loraine; Calle, Carlos I.

    2011-01-01

    Manned exploration missions to Mars will need dependable in situ resource utilization (ISRU) for the production of oxygen and other commodities. One of these resources is the Martian atmosphere itself, which is composed of carbon dioxide (95.3%), nitrogen (2.7%), argon (1.6%), oxygen (0.13%), carbon monoxide (0.07%), and water vapor (0.03%), as well as other trace gases. However, the Martian atmosphere also contains relatively large amounts of dust, uploaded by frequent dust devils and high Winds. To make this gas usable for oxygen extraction in specialized chambers requires the removal of most of the dust. An electrostatic precipitator (ESP) system is an obvious choice. But with an atmospheric pressure just one-hundredth of Earth's, electrical breakdown at low voltages makes the implementation of the electrostatic precipitator technology very challenging. Ion mobility, drag forces, dust particle charging, and migration velocity are also affected because the low gas pressure results in molecular mean free paths that are approximately one hundred times longer than those at Earth .atmospheric pressure. We report here on our efforts to develop this technology at the Kennedy Space Center, using gases with approximately the same composition as the Martian atmosphere in a vacuum chamber at 9 mbars, the atmospheric pressure on Mars. We also present I-V curves and large particle charging data for various versions of wire-cylinder and rod-cylinder geometry ESPs. Preliminary results suggest that use of an ESP for dust collection on Mars may be feasible, but further testing with Martian dust simulant is required.

  10. Implications of Rheumatic Disease and Biological Response-Modifying Agents in Plastic Surgery.

    PubMed

    Tsai, David M; Borah, Gregory L

    2015-12-01

    The preoperative evaluation for any reconstructive or aesthetic procedure requires a detailed history of existing medical conditions and current home medications. The prevalence of rheumatic diseases such as rheumatoid arthritis, gout, and psoriasis is high, but the impact of these chronic illnesses on surgical outcome and the side effects of the powerful medications used for treatment are often underappreciated. In this review, the authors highlight key perioperative considerations specific to rheumatologic diseases and their associated pharmacologic therapies. In particular, the authors discuss the perioperative management of biological response-modifying agents, which have largely become the new standard of therapy for many rheumatic diseases. The literature reveals three key perioperative concerns with biological therapy for rheumatic disease: infection, wound healing delays, and disease flare. However, data on specific perioperative complications are lacking, and it remains controversial whether withholding biological therapy before surgery is of benefit. The risk of these adverse events is influenced by several factors: age, sex, class of biological agent, duration of exposure, dosage, onset and severity of disease, and type of surgical procedure. Overall, it remains best to develop an individualized plan. In younger patients with recent onset of biological therapy, it is reasonable to withhold therapy based on 3 to 5 half-lives of the specific agent. In older patients with a substantial history of rheumatic disease, the decision to discontinue therapy must be weighed and decided carefully in conjunction with the rheumatologist.

  11. The 2010 ILSO-ISRU Field Test at Mauna Kea, Hawaii: Results from the Miniaturised Mossbauer Spectrometers Mimos II and Mimos IIA

    NASA Technical Reports Server (NTRS)

    Klingelhoefer, G.; Morris, R. V.; Blumers, M.; Bernhardt, B.; Graff, T.

    2011-01-01

    For the advanced Moessbauer instrument MIMOS IIA, the new detector technologies and electronic components increase sensitivity and performance significantly. In combination with the high energy resolution of the SDD it is possible to perform X-ray fluorescence analysis simultaneously to Moessbauer spectroscopy. In addition to the Fe-mineralogy, information on the sample's elemental composition will be gathered. The ISRU 2010 field campaign demonstrated that in-situ Moessbauer spectroscopy is an effective tool for both science and feedstock exploration and process monitoring. Engineering tests showed that a compact nickel metal hydride battery provided sufficient power for over 12 hr of continuous operation for the MIMOS instruments.

  12. Population biology of coral trout species in eastern Torres Strait: Implications for fishery management

    NASA Astrophysics Data System (ADS)

    Williams, Ashley J.; Currey, Leanne M.; Begg, Gavin A.; Murchie, Cameron D.; Ballagh, Aaron C.

    2008-09-01

    Coral trout ( Plectropomus spp.) are the main target species for commercial fishers in the eastern Torres Strait Reef Line Fishery (ETS RLF). The four species of coral trout known to occur in Torres Strait: Plectropomus leopardus, Plectropomus maculatus, Plectropomus areolatus and Plectropomus laevis are currently managed as a single species in Torres Strait, as there is no species-specific biological information available for the region which could be used to assess whether species differ in their response to fishing pressure. The aim of our study was to determine whether it is appropriate (biologically) to manage coral trout in the ETS RLF as a single species group or whether different management arrangements are required for some species. We used catch data and biological data from samples collected by commercial fishers to examine the distribution within Torres Strait and estimate a range of biological parameters for P. leopardus, P. maculatus and P. areolatus. Insufficient P. laevis samples were collected to reliably examine this species. Results indicated that the population biology, particularly the reproductive biology, of P. areolatus was substantially different to both P. leopardus and P. maculatus. Although it is difficult to predict the response to fishing, P. areolatus may be more vulnerable to fishing than P. leopardus and P. maculatus, due to the larger size at sex change observed for this species and the very low proportion of males protected by the current minimum size limit. Therefore, while the common management arrangements for P. leopardus and P. maculatus appear to be adequate for these species, separate management arrangements are needed for the sustainable harvest of P. areolatus populations in the ETS. Specifically, we recommend the introduction of a maximum size limit for P. areolatus, in addition to the current minimum size limit, which may allow a proportion of males some protection from fishing.

  13. Implications of Developmental Gene Regulatory Networks Inside and Outside Developmental Biology.

    PubMed

    Peter, Isabelle S; Davidson, Eric H

    2016-01-01

    The insight that the genomic control of developmental process is encoded in the form of gene regulatory networks has profound impacts on many areas of modern bioscience. Most importantly, it affects developmental biology itself, as it means that a causal understanding of development requires knowledge of the architecture of regulatory network interactions. Furthermore, it follows that functional changes in developmental gene regulatory networks have to be considered as a primary mechanism for evolutionary process. We here discuss some of the recent advances in gene regulatory network biology and how they have affected our current understanding of development, evolution, and regulatory genomics.

  14. Developmental Changes in Children's Inductive Inferences for Biological Concepts: Implications for the Development of Essentialist Beliefs

    ERIC Educational Resources Information Center

    Farrar, M. Jeffrey; Boyer-Pennington, Michelle

    2011-01-01

    We examined developmental changes in children's inductive inferences about biological concepts as a function of knowledge of properties and concepts. Specifically, 4- to 5-year-olds and 9- to 10-year-olds were taught either familiar or unfamiliar internal, external, or functional properties about known and unknown target animals. Children were…

  15. Biological invasions on oceanic islands: Implications for island ecosystems and avifauna

    Treesearch

    Dean E. Pearson

    2009-01-01

    Biological invasions present a global threat to biodiversity, but oceanic islands are the systems hardest hit by invasions. Islands are generally depauperate in species richness, trophic complexity, and functional diversity relative to comparable mainland ecosystems. This situation results in low biotic resistance to invasion and many empty niches for invaders to...

  16. Role of biological soil crusts in desert hydrology and geomorphology: Implications for military training operations

    Treesearch

    Steven D. Warren

    2014-01-01

    Biological soil crusts, composed of soil surfaces stabilized by a consortium of cyanobacteria, algae, fungi, lichens, and/or bryophytes, are common in most deserts and perform functions of primary productivity, nitrogen fixation, nutrient cycling, water redistribution, and soil stabilization. The crusts are highly susceptible to disturbance. The degree of perturbation...

  17. Genetic control of chromosome behaviour: Implications in evolution, crop improvement, and human biology

    USDA-ARS?s Scientific Manuscript database

    Chromosomes and chromosome pairing are pivotal to all biological sciences. The study of chromosomes helps unravel several aspects of an organism. Although the foundation of genetics occurred with the formulation of the laws of heredity in 1865, long before the discovery of chromosomes, their subsequ...

  18. Approaches to Learning by Students in the Biological Sciences: Implications for Teaching

    ERIC Educational Resources Information Center

    Watters, Dianne J.; Watters, James J.

    2007-01-01

    This study is an investigation of the epistemological beliefs and study habits of students undertaking first-year courses in Biological Chemistry and Biochemistry. In particular, we were interested in the relationship between students' epistemological beliefs about learning and knowledge, approaches to learning, and achievement. The study adopted…

  19. Dissertation Citations in Organismal Biology at Southern Illinois University at Carbondale: Implications for Collection Development

    ERIC Educational Resources Information Center

    Nabe, Jonathan; Imre, Andrea

    2008-01-01

    We report on a citation analysis of Ph.D. dissertations in plant biology and zoology at Southern Illinois University Carbondale, undertaken to test the common assumption that scientists favor current research to such an extent that journal backfiles can be de-emphasized in academic library collections. Results demonstrate otherwise. The study is…

  20. High School Biology Teachers' Views on Teaching Evolution: Implications for Science Teacher Educators

    ERIC Educational Resources Information Center

    Hermann, Ronald S.

    2013-01-01

    In the US, there may be few scientific concepts that students maintain preconceived ideas about as strongly and passionately as they do with regard to evolution. At the confluence of a multitude of social, religious, political, and scientific factors lies the biology teacher. This phenomenological study provides insight into the salient aspects of…

  1. Diversity of the Burkholderia cepacia complex and implications for risk assessment of biological control strains.

    PubMed

    Parke, J L; Gurian-Sherman, D

    2001-01-01

    The Burkholderia cepacia complex (Bcc) consists of several species of closely related and extremely versatile gram-negative bacteria found naturally in soil, water, and the rhizosphere of plants. Strains of Bcc have been used in biological control of plant diseases and bioremediation, while some strains are plant pathogens or opportunistic pathogens of humans with cystic fibrosis. The ecological versatility of these bacteria is likely due to their unusually large genomes, which are often comprised of several (typically two or three) large replicons, as well as their ability to use a large array of compounds as sole carbon sources. The original species B. cepacia has been split into eight genetic species (genomovars), including five named species, but taxonomic distinctions have not enabled biological control strains to be clearly distinguished from human pathogenic strains. This has led to a reassessment of the risk of several strains registered by the U.S. Environmental Protection Agency for biological control. We review the biology of Bcc bacteria, especially how our growing knowledge of Bcc ecology and pathogenicity might be used in risk assessment. The capability of this bacterial complex to cause disease in plants and humans, as well as to control plant diseases, affords a rare opportunity to explore traits that may function in all three environments.

  2. THE INFLUENCE OF CATCHMENT LAND USE ON HYDROGRAPH DYNAMICS AND IMPLICATIONS FOR STREAM BIOLOGICAL ASSEMBLAGES

    EPA Science Inventory

    Catchment land use impacts the rise and fall dynamic of hydrographs, and may also help explain variation in biological assemblages known to be sensitive to flow regime. We collected continuous stream depth records for the 2002 water year (5 min. intervals) from eight streams dra...

  3. High School Biology Teachers' Views on Teaching Evolution: Implications for Science Teacher Educators

    ERIC Educational Resources Information Center

    Hermann, Ronald S.

    2013-01-01

    In the US, there may be few scientific concepts that students maintain preconceived ideas about as strongly and passionately as they do with regard to evolution. At the confluence of a multitude of social, religious, political, and scientific factors lies the biology teacher. This phenomenological study provides insight into the salient aspects of…

  4. Evolutionary interactions between the invasive tallow tree and herbivores: implications for biological control

    USDA-ARS?s Scientific Manuscript database

    Understanding interactions between insect agents and host plants is critical for forecasting their impact before the insects are introduced, and for improving our knowledge of the mechanisms driving success or failure in biological weed control. As invasive plants may undergo rapid adaptive evolutio...

  5. Long-term biological effects induced by ionizing radiation--implications for dose mediated risk.

    PubMed

    Miron, S D; Astărăstoae, V

    2014-01-01

    Ionizing radiations are considered to be risk agents that are responsible for the effects on interaction with living matter. The occurring biological effects are due to various factors such as: dose, type of radiation, exposure time, type of biological tissue, health condition and the age of the person exposed. The mechanisms involved in the direct modifications of nuclear DNA and mitochondrial DNA are reviewed. Classical target theory of energy deposition in the nucleus that causes DNA damages, in particular DNA double-strand breaks and that explanation of the biological consequences of ionizing radiation exposure is a paradigm in radiobiology. Recent experimental evidences have demonstrated the existence of a molecular mechanism that explains the non-targeted effects of ionizing radiation exposure. Among these novel data, genomic instability and a variety of bystander effects are discussed here. Those bystander effects of ionizing radiation are fulfilled by cellular communication systems that give rise to non-targeted effects in the neighboring non irradiated cells. This paper provides also a commentary on the synergistic effects induced by the co-exposures to ionizing radiation and various physical agents such as electromagnetic fields and the co-exposures to ionizing radiation and chemical environmental contaminants such as metals. The biological effects of multiple stressors on genomic instability and bystander effects are also discussed. Moreover, a brief presentation of the methods used to characterize cyto- and genotoxic damages is offered.

  6. Dissertation Citations in Organismal Biology at Southern Illinois University at Carbondale: Implications for Collection Development

    ERIC Educational Resources Information Center

    Nabe, Jonathan; Imre, Andrea

    2008-01-01

    We report on a citation analysis of Ph.D. dissertations in plant biology and zoology at Southern Illinois University Carbondale, undertaken to test the common assumption that scientists favor current research to such an extent that journal backfiles can be de-emphasized in academic library collections. Results demonstrate otherwise. The study is…

  7. Biological cost of fluoroquinolone resistance in Escherichia coli implicated in polyclonal infection.

    PubMed

    Bémer, P; Corvec, S; Guitton, C; Giraudeau, C; Le Gargasson, G; Espaze, E; Drugeon, H

    2007-07-01

    Polyclonal Escherichia coli strains were isolated in a transplanted patient who experienced successive septic shocks. Fluoroquinolone susceptible and resistant strains were corresponding to different PFGE fragment profiles. The gyrA S83L mutation was associated with a reduction in biological fitness. Resistant strain was selected by a long-term single use of ofloxacin.

  8. Biological contributions to addictions in adolescents and adults: prevention, treatment, and policy implications.

    PubMed

    Potenza, Marc N

    2013-02-01

    Despite significant advances in our understanding of the biological bases of addictions, these disorders continue to represent a huge public health burden that is associated with substantial personal suffering. Efforts to target addictions require consideration of how the improved biological understanding of addictions may lead to improved prevention, treatment, and policy initiatives. In this article, we provide a narrative review of current biological models for addictions with a goal of placing existing data and theories within a translational and developmental framework targeting the advancement of prevention, treatment, and policy strategies. Data regarding individual differences, intermediary phenotypes, and main and interactive influences of genetic and environmental contributions in the setting of developmental trajectories that may be influenced by addictive drugs or behavior indicate complex underpinnings of addictions. Consideration and further elucidation of the biological etiologies of addictions hold significant potential for making important gains and reducing the public health impact of addictions. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  9. Developmental Changes in Children's Inductive Inferences for Biological Concepts: Implications for the Development of Essentialist Beliefs

    ERIC Educational Resources Information Center

    Farrar, M. Jeffrey; Boyer-Pennington, Michelle

    2011-01-01

    We examined developmental changes in children's inductive inferences about biological concepts as a function of knowledge of properties and concepts. Specifically, 4- to 5-year-olds and 9- to 10-year-olds were taught either familiar or unfamiliar internal, external, or functional properties about known and unknown target animals. Children were…

  10. THE INFLUENCE OF CATCHMENT LAND USE ON HYDROGRAPH DYNAMICS AND IMPLICATIONS FOR STREAM BIOLOGICAL ASSEMBLAGES

    EPA Science Inventory

    Catchment land use impacts the rise and fall dynamic of hydrographs, and may also help explain variation in biological assemblages known to be sensitive to flow regime. We collected continuous stream depth records for the 2002 water year (5 min. intervals) from eight streams dra...

  11. Effects of imputation on correlation: implications for analysis of mass spectrometry data from multiple biological matrices.

    PubMed

    Taylor, Sandra L; Ruhaak, L Renee; Kelly, Karen; Weiss, Robert H; Kim, Kyoungmi

    2017-03-01

    With expanded access to, and decreased costs of, mass spectrometry, investigators are collecting and analyzing multiple biological matrices from the same subject such as serum, plasma, tissue and urine to enhance biomarker discoveries, understanding of disease processes and identification of therapeutic targets. Commonly, each biological matrix is analyzed separately, but multivariate methods such as MANOVAs that combine information from multiple biological matrices are potentially more powerful. However, mass spectrometric data typically contain large amounts of missing values, and imputation is often used to create complete data sets for analysis. The effects of imputation on multiple biological matrix analyses have not been studied. We investigated the effects of seven imputation methods (half minimum substitution, mean substitution, k-nearest neighbors, local least squares regression, Bayesian principal components analysis, singular value decomposition and random forest), on the within-subject correlation of compounds between biological matrices and its consequences on MANOVA results. Through analysis of three real omics data sets and simulation studies, we found the amount of missing data and imputation method to substantially change the between-matrix correlation structure. The magnitude of the correlations was generally reduced in imputed data sets, and this effect increased with the amount of missing data. Significant results from MANOVA testing also were substantially affected. In particular, the number of false positives increased with the level of missing data for all imputation methods. No one imputation method was universally the best, but the simple substitution methods (Half Minimum and Mean) consistently performed poorly. © The Author 2016. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  12. Integrated Bio-ISRU and Life Support Systems at the Lunar Outpost: Concept and Preliminary Results

    NASA Technical Reports Server (NTRS)

    Brown, I. I.; Garrison, D. H.; Allen, C. C.; Pickering, K.; Sarkisova, S. A.; Galindo, C., Jr.; Pan, D.; Foraker, E.; Mckay, D. S.

    2009-01-01

    We continue the development of our concept of a biotechnological loop for in-situ resource extraction along with propellant and food production at a future lunar outpost, based on the cultivation of litholytic cyanobacteria (LCB) with lunar regolith (LR) in a geobioreactor energized by sunlight. Our preliminary studies have shown that phototropic cultivation of LCB with simulants of LR in a low-mineralized medium supplemented with CO2 leads to rock dissolution (bioweathering) with the resulting accumulation of Fe, Mg and Al in cyanobacterial cells and in the medium. LCB cultivated with LR simulants produces more O2 than the same organisms cultivated in a high-mineralized medium. The loss of rock mass after bioweathering with LCB suggests the release of O from regolith. Further studies of chemical pathways of released O are required. The bioweathering process is limited by the availability of CO2, N, and P. Since lunar regolith is mainly composed of O, Si, Ca, Al and Mg, we propose to use organic waste to supply a geobioreactor with C, N and P. The recycling of organic waste, including urine, through a geobioreactor will allow for efficient element extraction as well as oxygen and biomass production. The most critical conclusion is that a biological life support system tied to a geobioreactor might be more efficient for supporting an extraterrestrial outpost than a closed environmental system.

  13. Integrated Bio-ISRU and Life Support Systems at the Lunar Outpost: Concept and Preliminary Results

    NASA Technical Reports Server (NTRS)

    Brown, I. I.; Garrison, D. H.; Allen, C. C.; Pickering, K.; Sarkisova, S. A.; Galindo, C., Jr.; Pan, D.; Foraker, E.; Mckay, D. S.

    2009-01-01

    We continue the development of our concept of a biotechnological loop for in-situ resource extraction along with propellant and food production at a future lunar outpost, based on the cultivation of litholytic cyanobacteria (LCB) with lunar regolith (LR) in a geobioreactor energized by sunlight. Our preliminary studies have shown that phototropic cultivation of LCB with simulants of LR in a low-mineralized medium supplemented with CO2 leads to rock dissolution (bioweathering) with the resulting accumulation of Fe, Mg and Al in cyanobacterial cells and in the medium. LCB cultivated with LR simulants produces more O2 than the same organisms cultivated in a high-mineralized medium. The loss of rock mass after bioweathering with LCB suggests the release of O from regolith. Further studies of chemical pathways of released O are required. The bioweathering process is limited by the availability of CO2, N, and P. Since lunar regolith is mainly composed of O, Si, Ca, Al and Mg, we propose to use organic waste to supply a geobioreactor with C, N and P. The recycling of organic waste, including urine, through a geobioreactor will allow for efficient element extraction as well as oxygen and biomass production. The most critical conclusion is that a biological life support system tied to a geobioreactor might be more efficient for supporting an extraterrestrial outpost than a closed environmental system.

  14. Molecular biology in marine science: Scientific questions, technological approaches, and practical implications

    SciTech Connect

    1994-12-31

    This report describes molecular techniques that could be invaluable in addressing process-oriented problems in the ocean sciences that have perplexed oceanographers for decades, such as understanding the basis for biogeochemical processes, recruitment processes, upper-ocean dynamics, biological impacts of global warming, and ecological impacts of human activities. The coupling of highly sophisticated methods, such as satellite remote sensing, which permits synoptic monitoring of chemical, physical, and biological parameters over large areas, with the power of modern molecular tools for ``ground truthing`` at small scales could allow scientists to address questions about marine organisms and the ocean in which they live that could not be answered previously. Clearly, the marine sciences are on the threshold of an exciting new frontier of scientific discovery and economic opportunity.

  15. [Glutamate and malignant gliomas, from epilepsia to biological aggressiveness: therapeutic implications].

    PubMed

    Blecic, Serge; Rynkowski, Michal; De Witte, Olivier; Lefranc, Florence

    2013-09-01

    In this review article, we describe the unrecognized roles of glutamate and glutamate receptors in malignant glioma biology. The neurotransmitter glutamate released from malignant glioma cells in the extracellular matrix is responsible for seizure induction and at higher concentration neuronal cell death. This neuronal cell death will create vacated place for tumor growth. Glutamate also stimulates the growth and the migration of glial tumor cells by means of the activation of glutamate receptors on glioma cells in a paracrine and autocrine manner. The multitude of effects of glutamate in glioma biology supports the rationale for pharmacological targeting of glutamate receptors and transporters in the adjuvant treatment of malignant gliomas in neurology and neuro-oncology. Using the website www.clinicaltrials.gov/ as a reference - a service developed by the National Library of Medicine for the National Health Institute in USA - we have evoked the few clinical trials completed and currently ongoing with therapies targeting the glutamate receptors.

  16. High School Biology Teachers' Views on Teaching Evolution: Implications for Science Teacher Educators

    NASA Astrophysics Data System (ADS)

    Hermann, Ronald S.

    2013-06-01

    In the US, there may be few scientific concepts that students maintain preconceived ideas about as strongly and passionately as they do with regard to evolution. At the confluence of a multitude of social, religious, political, and scientific factors lies the biology teacher. This phenomenological study provides insight into the salient aspects of teaching evolution as viewed by public high school biology teachers. Transcribed interviews were coded, and data were sorted resulting in key themes regarding teachers' views of evolution education. These themes are presented against the backdrop of extant literature on the teaching and learning of evolution. Suggestions for science teacher educators are presented such that we can modify teacher preparation programs to better prepare science teachers to meet the challenges of teaching evolution.

  17. Weak-field ELF magnetic interactions: Implications for biological change during paleomagnetic reversals.

    PubMed

    Liboff, Abraham R

    2013-12-01

    Contrary to the belief that paleomagnetic reversals are not biologically significant, we find good reason to think otherwise. Attention is drawn to polarity transitions, time intervals a few thousand years long that follow the collapse of the existing geomagnetic dipole moment and precede the establishment of the new, oppositely directed moment. The geomagnetic field during transitions is reduced to a maximal mean intensity about 10% of the stable field and can exhibit low-frequency perturbations comparable to numerous laboratory-based extremely low frequency (ELF) studies reporting biological interactions, making it very likely that similar interactions must occur over the course of a polarity transition. This conclusion is strengthened by reports of medical problems that significantly correlate with intense solar winds, events that also generate ELF perturbations similar to those that can occur during polarity transitions.

  18. Sphingosine 1-phosphate regulates cytoskeleton dynamics: implications in its biological response.

    PubMed

    Donati, Chiara; Bruni, Paola

    2006-12-01

    The bioactive sphingolipid sphingosine 1-phosphate (S1P) elicits robust cytoskeletal rearrangement in a large variety of cell systems, mainly acting through a panel of specific cell surface receptors, named S1P receptors. Recent studies have begun to delineate the molecular mechanisms involved in the complex process responsible for cytoskeletal rearrangement following S1P ligation to its receptors. Notably, changes of cell shape and/or motility induced by S1P via cytoskeletal remodelling are functional to the biological action exerted by S1P which appears to be highly cell-specific. This review focuses on the current knowledge of the regulatory mechanisms of cytoskeleton dynamics elicited by S1P, with special emphasis on the relationship between cytoskeletal remodelling and the biological effects evoked by the sphingolipid in various cell types.

  19. Implications of biological factors on accumulation of persistent organic pollutants in Antarctic notothenioid fish.

    PubMed

    Ríos, J M; Lana, N B; Ciocco, N F; Covaci, A; Barrera-Oro, E; Moreira, E; Altamirano, J C

    2017-11-01

    In the present study, the possible associations between selected persistent organic pollutants (POPs) and biological factors were assessed in different tissues of two Antarctic notothenioid fish: Notothenia rossii (NOR) and Trematomus newnesi (TRN) collected at Potter Cove, King George Island/Isla 25 de Mayo, South Shetland Islands. Specifically, association patterns between biological factors (body size, lipid content, body condition) and POP concentrations (polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and metabolites, polybrominated diphenyl ethers (PBDEs), and hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), chlordanes (CHLs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs)), were explored by using two approaches: multivariate analyses (principal component analysis: PCA) and intraspecific correlations. Integrating results suggest that biological factors such as size, KI and tissue type seemed to be associated to selective accumulation of POPs for immature specimens of N. rossii, and KI and tissue type for mature specimens of T. newnesi. Each particular factor should be considered when choosing N. rossii or T. newnesi as sentinels for POPs pollution in Antarctic marine environments. Further, both nototheniids showed a selective accumulation pattern in their gonads of penta-chlorinated biphenyls (penta-CBs; 55.5 and 29ngg(-1) lw for N. rossii and T. newnesi, respectively) and organochlorine pesticides such as DDTs (199 and 13.3ngg(-1) lw, for N. rossii and T. newnesi respectively), and of polybrominated diphenyl ethers (PBDEs) in gills (97.2 and 22.1 for ngg(-1) lw, for N. rossii and T. newnesi, respectively), highlighting the importance of these tissues in monitoring studies of pollution in fish. The current study expands the knowledge concerning the biological factors to be investigated when specific pollutants are monitored and supports the importance of tissue type for the selective accumulation of POPs in Antarctic

  20. Relative biological effectiveness for photons: implication of complex DNA double-strand breaks as critical lesions.

    PubMed

    Liang, Ying; Fu, Qibin; Wang, Xudong; Liu, Feng; Yang, Gen; Luo, Chunxiong; Ouyang, Qi; Wang, Yugang

    2017-03-21

    Current knowledge in radiobiology ascribes the adverse biological effects of ionizing radiation primarily to the induction of DNA double-strand breaks (DSBs), which is supposed to be potentially lethal and may be converted to lethal damage due to misrepair. Soft and ultrasoft x-rays have been found to bear elevated biological effectiveness for cell killing compared with conventional x-rays or (60)Co γ-rays. This phenomenon is qualitatively interpreted as the increased level of DSB induction for low energy photons, however, a thorough quantitative reasoning is lacking. Here, we systematically compared the relative biological effectiveness (RBE) with relative DSB induction for photons from several hundreds of eV up to MeV. Although there is an approximate two-fold increase in the yields of DSB for low energy photons found in our calculation and a large number of experimental measurements, it is far from enough to account for the three- to four-fold increase in RBE. Further theoretical investigations show that DSB complexity (additional single-strand breaks and base damage within 10 base pairs) increases notably for low energy photons, which largely reconciles the discrepancy between RBE and DSB induction. Our theoretical results are in line with accumulating experimental evidence that complex DSBs are refractory to repair machinery and may contribute predominantly to the formation of lethal damage.

  1. Relative biological effectiveness for photons: implication of complex DNA double-strand breaks as critical lesions

    NASA Astrophysics Data System (ADS)

    Liang, Ying; Fu, Qibin; Wang, Xudong; Liu, Feng; Yang, Gen; Luo, Chunxiong; Ouyang, Qi; Wang, Yugang

    2017-03-01

    Current knowledge in radiobiology ascribes the adverse biological effects of ionizing radiation primarily to the induction of DNA double-strand breaks (DSBs), which is supposed to be potentially lethal and may be converted to lethal damage due to misrepair. Soft and ultrasoft x-rays have been found to bear elevated biological effectiveness for cell killing compared with conventional x-rays or 60Co γ-rays. This phenomenon is qualitatively interpreted as the increased level of DSB induction for low energy photons, however, a thorough quantitative reasoning is lacking. Here, we systematically compared the relative biological effectiveness (RBE) with relative DSB induction for photons from several hundreds of eV up to MeV. Although there is an approximate two-fold increase in the yields of DSB for low energy photons found in our calculation and a large number of experimental measurements, it is far from enough to account for the three- to four-fold increase in RBE. Further theoretical investigations show that DSB complexity (additional single-strand breaks and base damage within 10 base pairs) increases notably for low energy photons, which largely reconciles the discrepancy between RBE and DSB induction. Our theoretical results are in line with accumulating experimental evidence that complex DSBs are refractory to repair machinery and may contribute predominantly to the formation of lethal damage.

  2. Adaptive evolution of a generalist parasitoid: implications for the effectiveness of biological control agents

    PubMed Central

    Zepeda-Paulo, Francisca A; Ortiz-Martínez, Sebastián A; Figueroa, Christian C; Lavandero, Blas

    2013-01-01

    The use of alternative hosts imposes divergent selection pressures on parasitoid populations. In response to selective pressures, these populations may follow different evolutionary trajectories. Divergent natural selection could promote local host adaptation in populations, translating into direct benefits for biological control, thereby increasing their effectiveness on the target host. Alternatively, adaptive phenotypic plasticity could be favored over local adaptation in temporal and spatially heterogeneous environments. We investigated the existence of local host adaptation in Aphidius ervi, an important biological control agent, by examining different traits related to infectivity (preference) and virulence (a proxy of parasitoid fitness) on different aphid-host species. The results showed significant differences in parasitoid infectivity on their natal host compared with the non-natal hosts. However, parasitoids showed a similar high fitness on both natal and non-natal hosts, thus supporting a lack of host adaptation in these introduced parasitoid populations. Our results highlight the role of phenotypic plasticity in fitness-related traits of parasitoids, enabling them to maximize fitness on alternative hosts. This could be used to increase the effectiveness of biological control. In addition, A. ervi females showed significant differences in infectivity and virulence across the tested host range, thus suggesting a possible host phylogeny effect for those traits. PMID:24062806

  3. Adaptive evolution of a generalist parasitoid: implications for the effectiveness of biological control agents.

    PubMed

    Zepeda-Paulo, Francisca A; Ortiz-Martínez, Sebastián A; Figueroa, Christian C; Lavandero, Blas

    2013-09-01

    The use of alternative hosts imposes divergent selection pressures on parasitoid populations. In response to selective pressures, these populations may follow different evolutionary trajectories. Divergent natural selection could promote local host adaptation in populations, translating into direct benefits for biological control, thereby increasing their effectiveness on the target host. Alternatively, adaptive phenotypic plasticity could be favored over local adaptation in temporal and spatially heterogeneous environments. We investigated the existence of local host adaptation in Aphidius ervi, an important biological control agent, by examining different traits related to infectivity (preference) and virulence (a proxy of parasitoid fitness) on different aphid-host species. The results showed significant differences in parasitoid infectivity on their natal host compared with the non-natal hosts. However, parasitoids showed a similar high fitness on both natal and non-natal hosts, thus supporting a lack of host adaptation in these introduced parasitoid populations. Our results highlight the role of phenotypic plasticity in fitness-related traits of parasitoids, enabling them to maximize fitness on alternative hosts. This could be used to increase the effectiveness of biological control. In addition, A. ervi females showed significant differences in infectivity and virulence across the tested host range, thus suggesting a possible host phylogeny effect for those traits.

  4. Biological and chemical terrorism scenarios and implications for detection systems needs

    NASA Astrophysics Data System (ADS)

    Gordon, Susanna P.; Chumfong, Isabelle; Edwards, Donna M.; Gleason, Nathaniel J.; West, Todd; Yang, Lynn

    2007-04-01

    Terrorists intent on causing many deaths and severe disruption to our society could, in theory, cause hundreds to tens of thousands of deaths and significant contamination of key urban facilities by using chemical or biological (CB) agents. The attacks that have occurred to date, such as the 1995 Aum Shinrikyo CB attacks and the 2001 anthrax letters, have been very small on the scale of what is possible. In order to defend against and mitigate the impacts of large-scale terrorist attacks, defensive systems for protection of urban areas and high-value facilities from biological and chemical threats have been deployed. This paper reviews analyses of such scenarios and of the efficacy of potential response options, discusses defensive systems that have been deployed and detectors that are being developed, and finally outlines the detection systems that will be needed for improved CB defense in the future. Sandia's collaboration with San Francisco International Airport on CB defense will also be briefly reviewed, including an overview of airport facility defense guidelines produced in collaboration with Lawrence Berkeley National Laboratory. The analyses that will be discussed were conducted by Sandia National Laboratories' Systems Studies Department in support of the U.S. Department of Homeland Security (DHS) Science and Technology Directorate, and include quantitative analyses utilizing simulation models developed through close collaboration with subject matter experts, such as public health officials in urban areas and biological defense experts.

  5. On the biological plausibility of grandmother cells: implications for neural network theories in psychology and neuroscience.

    PubMed

    Bowers, Jeffrey S

    2009-01-01

    A fundamental claim associated with parallel distributed processing (PDP) theories of cognition is that knowledge is coded in a distributed manner in mind and brain. This approach rejects the claim that knowledge is coded in a localist fashion, with words, objects, and simple concepts (e.g. "dog"), that is, coded with their own dedicated representations. One of the putative advantages of this approach is that the theories are biologically plausible. Indeed, advocates of the PDP approach often highlight the close parallels between distributed representations learned in connectionist models and neural coding in brain and often dismiss localist (grandmother cell) theories as biologically implausible. The author reviews a range a data that strongly challenge this claim and shows that localist models provide a better account of single-cell recording studies. The author also contrast local and alternative distributed coding schemes (sparse and coarse coding) and argues that common rejection of grandmother cell theories in neuroscience is due to a misunderstanding about how localist models behave. The author concludes that the localist representations embedded in theories of perception and cognition are consistent with neuroscience; biology only calls into question the distributed representations often learned in PDP models.

  6. Application of fish index of biological integrity (FIBI) in the Sanmenxia Wetland with water quality implications.

    PubMed

    Zhang, Hong; Shan, Baoqing; Ao, Liang

    2014-08-01

    Long-term changes of fish biotic integrity in the Sanmenxia Wetland, North China, since the 1950s were assessed using the fish index of biological integrity (FIBI). The water and sediment quality was evaluated by the water quality index (WQI) and sediment pollution index (SPI). The results showed that FIBI continuously decreased from 46 to 20 during the past 5 decades, which indicated that the fish community state shifted from fair to very poor conditions, and damming by itself did not affect the fish biotic integrity. At the same time, WQI fell from 83 to 44.1, and SPI increased from 0.99 to 2.14 since the 1960s, resulting from fast regional socio-economic development and insufficient wastewater treatment. Correlation analysis suggested that water quality significantly affected biotic integrity (r=0.867, p<0.05) through direct effects on the fish community. As a representative example of many wetlands in North China, our study clearly demonstrated that the biological integrity was degraded, induced both by water quality deterioration and sediment pollution, further driven by the contradiction between rapid development of regional economy and lagging development of sewage treatment facilities, which were thought to be the main factor responsible for the degradation of biological integrity. Copyright © 2014. Published by Elsevier B.V.

  7. Adhesion control by inflation: implications from biology to artificial attachment device

    NASA Astrophysics Data System (ADS)

    Dening, Kirstin; Heepe, Lars; Afferrante, Luciano; Carbone, Giuseppe; Gorb, Stanislav N.

    2014-08-01

    There is an increasing demand for materials that incorporate advanced adhesion properties, such as an ability to adhere in a reversible and controllable manner. In biological systems, these features are known from adhesive pads of the tree frog, Litoria caerulea, and the bush-cricket, Tettigonia viridissima. These species have convergently developed soft, hemispherically shaped pads that might be able to control their adhesion through active changing the curvature of the pad. Inspired by these biological systems, an artificial model system is developed here. It consists of an inflatable membrane clamped to the metallic cylinder and filled with air. Pull-off force measurements of the membrane surface were conducted in contact with the membrane at five different radii of curvature r c with (1) a smooth polyvinylsiloxane membrane and (2) mushroom-shaped adhesive microstructured membrane made of the same polymer. The hypothesis that an increased internal pressure, acting on the membrane, reduces the radius of the membrane curvature, resulting in turn in a lower pull-off force, is verified. Such an active control of adhesion, inspired by biological models, will lead to the development of industrial pick-and-drop devices with controllable adhesive properties.

  8. The non-biological meaning of the term "prokaryote" and its implications.

    PubMed

    Di Giulio, Massimo

    2015-02-01

    The meaning of the term prokaryote is critically analyzed. The conclusion reached is that this term does not have a real biological sense, above all because we are not able to link to this term a specific biological characteristic, i.e. the hypothetical evolutionary stage of the prokaryote would seem to have been unable to result in a completed cell, which could possibly be due to the recapitulation of the fundamental characteristics that might have been common to bacteria and archaea. This would define a biological immaturity of this evolutionary stage because otherwise we would have found traits already clearly defined at this level of cellular evolution. Therefore, the lack of well-defined traits characterising the prokaryote would seem to imply an evolutionary stage still in rapid evolution, i.e. with a tempo and a mode of evolution typical of a progenote. This in turn would seem to imply that the last universal common ancestor (LUCA) has been a progenote at least when the domains of life are only two-the bacterial and archaeal domains-because, in this case, the LUCA's node should coincide with that of prokaryote on the tree of life. Instead, if the root of the tree of life would be placed in the bacterial domain or in the archaeal one, we might again, very likely, have a LUCA with a character of progenote being, under these conditions, the LUCA a prokaryote-like organism.

  9. The ultraviolet environment of Mars: biological implications past, present, and future

    NASA Technical Reports Server (NTRS)

    Cockell, C. S.; Catling, D. C.; Davis, W. L.; Snook, K.; Kepner, R. L.; Lee, P.; McKay, C. P.

    2000-01-01

    A radiative transfer model is used to quantitatively investigate aspects of the martian ultraviolet radiation environment, past and present. Biological action spectra for DNA inactivation and chloroplast (photosystem) inhibition are used to estimate biologically effective irradiances for the martian surface under cloudless skies. Over time Mars has probably experienced an increasingly inhospitable photobiological environment, with present instantaneous DNA weighted irradiances 3.5-fold higher than they may have been on early Mars. This is in contrast to the surface of Earth, which experienced an ozone amelioration of the photobiological environment during the Proterozoic and now has DNA weighted irradiances almost three orders of magnitude lower than early Earth. Although the present-day martian UV flux is similar to that of early Earth and thus may not be a critical limitation to life in the evolutionary context, it is a constraint to an unadapted biota and will rapidly kill spacecraft-borne microbes not covered by a martian dust layer. Microbial strategies for protection against UV radiation are considered in the light of martian photobiological calculations, past and present. Data are also presented for the effects of hypothetical planetary atmospheric manipulations on the martian UV radiation environment with estimates of the biological consequences of such manipulations.

  10. The ultraviolet environment of Mars: biological implications past, present, and future.

    PubMed

    Cockell, C S; Catling, D C; Davis, W L; Snook, K; Kepner, R L; Lee, P; McKay, C P

    2000-08-01

    A radiative transfer model is used to quantitatively investigate aspects of the martian ultraviolet radiation environment, past and present. Biological action spectra for DNA inactivation and chloroplast (photosystem) inhibition are used to estimate biologically effective irradiances for the martian surface under cloudless skies. Over time Mars has probably experienced an increasingly inhospitable photobiological environment, with present instantaneous DNA weighted irradiances 3.5-fold higher than they may have been on early Mars. This is in contrast to the surface of Earth, which experienced an ozone amelioration of the photobiological environment during the Proterozoic and now has DNA weighted irradiances almost three orders of magnitude lower than early Earth. Although the present-day martian UV flux is similar to that of early Earth and thus may not be a critical limitation to life in the evolutionary context, it is a constraint to an unadapted biota and will rapidly kill spacecraft-borne microbes not covered by a martian dust layer. Microbial strategies for protection against UV radiation are considered in the light of martian photobiological calculations, past and present. Data are also presented for the effects of hypothetical planetary atmospheric manipulations on the martian UV radiation environment with estimates of the biological consequences of such manipulations.

  11. Biological reductive dechlorination of chlorinated ethylenes: Implications for natural attenuation and biostimulation

    SciTech Connect

    Distefano, T.D.

    1995-12-31

    Chlorinated organic compounds are the most frequently found contaminants at many hazardous waste sites and industrial facilities. Numerous industries use chlorinated organics such as tetrachloroethylene also known as perchloroethylene (PCE) -- and trichloroethylene (TCE), as degreasing agents, paint strippers, and in textile processing. These solvents are often detected as soil and ground water contaminants due to improper storage and disposal practices. Laboratory and full-scale investigations have proven that complete biological transformation of PCE and TCE is possible under anaerobic conditions. Biological treatment of chlorinated ethenes has received much interest due to the prevalence of these contaminants and the need to develop technologies that destroy contaminants rather than transfer them to other media. The purpose of this paper is to give an overview of the biological process by which anaerobic bacteria biodegrade chlorinated ethylenes. The benefits of this process are discussed along with key findings that may be employed to determine if dechlorination is occurring under natural conditions. Requirements of these bacteria are described and an assessment of future research needs is provided.

  12. The ultraviolet environment of Mars: biological implications past, present, and future

    NASA Technical Reports Server (NTRS)

    Cockell, C. S.; Catling, D. C.; Davis, W. L.; Snook, K.; Kepner, R. L.; Lee, P.; McKay, C. P.

    2000-01-01

    A radiative transfer model is used to quantitatively investigate aspects of the martian ultraviolet radiation environment, past and present. Biological action spectra for DNA inactivation and chloroplast (photosystem) inhibition are used to estimate biologically effective irradiances for the martian surface under cloudless skies. Over time Mars has probably experienced an increasingly inhospitable photobiological environment, with present instantaneous DNA weighted irradiances 3.5-fold higher than they may have been on early Mars. This is in contrast to the surface of Earth, which experienced an ozone amelioration of the photobiological environment during the Proterozoic and now has DNA weighted irradiances almost three orders of magnitude lower than early Earth. Although the present-day martian UV flux is similar to that of early Earth and thus may not be a critical limitation to life in the evolutionary context, it is a constraint to an unadapted biota and will rapidly kill spacecraft-borne microbes not covered by a martian dust layer. Microbial strategies for protection against UV radiation are considered in the light of martian photobiological calculations, past and present. Data are also presented for the effects of hypothetical planetary atmospheric manipulations on the martian UV radiation environment with estimates of the biological consequences of such manipulations.

  13. Dopamine-derived biological reactive intermediates and protein modifications: Implications for Parkinson's disease.

    PubMed

    Jinsmaa, Yunden; Florang, Virginia R; Rees, Jennifer N; Mexas, Lydia M; Eckert, Laurie L; Allen, Erin M G; Anderson, David G; Doorn, Jonathan A

    2011-06-30

    Dopamine (DA) undergoes monoamine oxidase catalyzed oxidative deamination to 3,4-dihydroxyphenylacetaldehyde (DOPAL), which is metabolized primarily to 3,4-dihydroxyphenylacetic acid (DOPAC) via aldehyde dehydrogenase (ALDH). Previous studies demonstrated DOPAL to be neurotoxic, more so than DA and other metabolites, and implicated the aldehyde intermediate as a factor in the pathogenesis of Parkinson's disease (PD). However, the mechanism for generation of DOPAL at aberrant levels and the pathways for toxicity are not conclusively known. Various models for DA catabolism revealed the susceptibility of DOPAL biotransformation (e.g., ALDH) to products of oxidative stress, e.g., 4-hydroxy-2-nonenal, at physiologic/pathologic levels and agents that induce oxidative stress. An elevated concentration of DOPAL correlated with increased protein modification with subsequent work demonstrating significant reactivity of the DA-derived electrophile toward protein nucleophiles compared to DA and other metabolites, e.g., DOPAC. The addition of DOPAL to proteins proceeds via reaction of the aldehyde with Lys residues, yielding a Schiff base; however, post-adduction chemistry occurs for the DOPAL-modification resulting in protein cross-linking. Preliminary work indicates enzymes in DA synthesis and catabolism to be cellular targets for DOPAL. Functional consequences for elevated levels of the DA-derived aldehyde and protein modification may include adverse cellular effects. These data implicate DOPAL as a toxic and reactive intermediate potentially serving as a "chemical trigger" for some stage of PD pathogenesis.

  14. Anisotropic buckling patterns in spheroidal film/substrate systems and their implications in some natural and biological systems

    NASA Astrophysics Data System (ADS)

    Yin, Jie; Chen, Xi; Sheinman, Izhak

    2009-09-01

    We establish a quantitative mechanics framework of elastic buckling of a spheroidal thin film/substrate system, which is highly relevant to the morphologies of quite a few natural and biological systems. The anisotropic stress-driven bifurcation is governed by the ratios between the effective size/thickness, the equatorial/polar radii, and the substrate/film moduli. The possibilities of manipulating the undulations through external constraints, anisotropic growth/material properties, and substrate geometry/structure are discussed. Analytical equations correlating the undulation characteristics with the geometry/material properties are derived. The quantitative mechanics framework established herein not only has important implications on the morphogenesis of various fruits, vegetables, nuts, eggs, tissues, and animal body parts, but also could guide the three-dimensional micro-fabrications via controlled self-assembly on curved substrate surfaces.

  15. A Systems Biology Methodology Combining Transcriptome and Interactome Datasets to Assess the Implications of Cytokinin Signaling for Plant Immune Networks.

    PubMed

    Kunz, Meik; Dandekar, Thomas; Naseem, Muhammad

    2017-01-01

    Cytokinins (CKs) play an important role in plant growth and development. Also, several studies highlight the modulatory implications of CKs for plant-pathogen interaction. However, the underlying mechanisms of CK mediating immune networks in plants are still not fully understood. A detailed analysis of high-throughput transcriptome (RNA-Seq and microarrays) datasets under modulated conditions of plant CKs and its mergence with cellular interactome (large-scale protein-protein interaction data) has the potential to unlock the contribution of CKs to plant defense. Here, we specifically describe a detailed systems biology methodology pertinent to the acquisition and analysis of various omics datasets that delineate the role of plant CKs in impacting immune pathways in Arabidopsis.

  16. Biological variation in a large sample of mouse lemurs from Amboasary, Madagascar: implications for interpreting variation in primate biology and paleobiology.

    PubMed

    Cuozzo, Frank P; Rasoazanabary, Emilienne; Godfrey, Laurie R; Sauther, Michelle L; Youssouf, Ibrahim Antho; LaFleur, Marni M

    2013-01-01

    template for recognizing the degree of variation manifested in a single primate population, and by implication, they provide minimum values for this species' intraspecific variation. Finally, discordance between different biological systems in our mouse lemur samples illustrates the need to examine multiple systems when conducting taxonomic analyses among living or fossil primates. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Differentially Expressed Genes Distributed Over Chromosomes and Implicated in Certain Biological Processes for Site Insertion Genetically Modified Rice Kemingdao

    PubMed Central

    Liu, Zhi; Li, Yunhe; Zhao, Jie; Chen, Xiuping; Jian, Guiliang; Peng, Yufa; Qi, Fangjun

    2012-01-01

    Release of genetically modified (GM) plants has sparked off intensive debates worldwide partly because of concerns about potential adverse unintended effects of GM plants to the agro system and the safety of foods. In this study, with the aim of revealing the molecular basis for unintended effects of a single site insertion GM Kemingdao (KMD) rice transformed with a synthetic cry1Ab gene, and bridging unintended effects of KMD rice through clues of differentially expressed genes, comparative transcriptome analyses were performed for GM KMD rice and its parent rice of Xiushui11 (XS11). The results showed that 680 differentially expressed transcripts were identified from 30-day old seedlings of GM KMD rice. The absolute majority of these changed expression transcripts dispersed and located over all rice chromosomes, and existed physical distance on chromosome from the insertion site, while only two transcripts were found to be differentially expressed within the 21 genes located within 100 kb up and down-stream of the insertion site. Pathway and biology function analyses further revealed that differentially expressed transcripts of KMD rice were involved in certain biological processes, and mainly implicated in two types of pathways. One type was pathways implicated in plant stress/defense responses, which were considerably in coordination with the reported unintended effects of KMD rice, which were more susceptible to rice diseases compared to its parent rice XS11; the other type was pathways associated with amino acids metabolism. With this clue, new unintended effects for changes in amino acids synthesis of KMD rice leaves were successfully revealed. Such that an actual case was firstly provided for identification of unintended effects in GM plants by comparative transciptome analysis. PMID:22811617

  18. Biological properties of dehydrated human amnion/chorion composite graft: implications for chronic wound healing.

    PubMed

    Koob, Thomas J; Rennert, Robert; Zabek, Nicole; Massee, Michelle; Lim, Jeremy J; Temenoff, Johnna S; Li, William W; Gurtner, Geoffrey

    2013-10-01

    Human amnion/chorion tissue derived from the placenta is rich in cytokines and growth factors known to promote wound healing; however, preservation of the biological activities of therapeutic allografts during processing remains a challenge. In this study, PURION® (MiMedx, Marietta, GA) processed dehydrated human amnion/chorion tissue allografts (dHACM, EpiFix®, MiMedx) were evaluated for the presence of growth factors, interleukins (ILs) and tissue inhibitors of metalloproteinases (TIMPs). Enzyme-linked immunosorbent assays (ELISA) were performed on samples of dHACM and showed quantifiable levels of the following growth factors: platelet-derived growth factor-AA (PDGF-AA), PDGF-BB, transforming growth factor α (TGFα), TGFβ1, basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), placental growth factor (PLGF) and granulocyte colony-stimulating factor (GCSF). The ELISA assays also confirmed the presence of IL-4, 6, 8 and 10, and TIMP 1, 2 and 4. Moreover, the relative elution of growth factors into saline from the allograft ranged from 4% to 62%, indicating that there are bound and unbound fractions of these compounds within the allograft. dHACM retained biological activities that cause human dermal fibroblast proliferation and migration of human mesenchymal stem cells (MSCs) in vitro. An in vivo mouse model showed that dHACM when tested in a skin flap model caused mesenchymal progenitor cell recruitment to the site of implantation. The results from both the in vitro and in vivo experiments clearly established that dHACM contains one or more soluble factors capable of stimulating MSC migration and recruitment. In summary, PURION® processed dHACM retains its biological activities related to wound healing, including the potential to positively affect four distinct and pivotal physiological processes intimately involved in wound healing: cell proliferation, inflammation, metalloproteinase activity and recruitment of progenitor cells. This suggests

  19. Dispersion of produced water in a coastal environment and its biological implications

    NASA Astrophysics Data System (ADS)

    Washburn, Libe; Stone, Shannon; MacIntyre, Sally

    1999-01-01

    Produced water, a pollutant associated with offshore oil production, has been shown to have adverse effects on marine organisms. We conducted a study of the dispersion of a produced water plume from an outfall in the Santa Barbara Channel near Carpinteria, CA. Biological effects were studied previously in a series of experiments which examined the toxicity of ocean waters near the outfall. To define the changing ocean conditions around the outfall, we obtained time series observations of currents and water properties from July, 1992 to January, 1994. Near-field dispersion of the produced water is simulated with a buoyant plume model. Measured currents and density profiles are used as model inputs. Far-field dispersion is simulated with the current statistics combined with an elementary solution to the diffusion equation. The modeled depth of the plume varies strongly with season due to changing stratification. In spring and summer, the modeled plume is trapped below the surface. In fall and winter it extends over most of the water column and occasionally surfaces. Minimum initial dilution is ˜100 in summer and ˜500 in winter. Far-field modeling indicates along-isobath symmetry in produced water dispersion in the mid water column. This pattern agrees with the distribution of toxic effects from the biological studies. At 1000 m from the outfall, the farthest test sites in the biological studies, minimum dilutions range from 4000 to 4×10 5 when the plume is present. These estimates exceed the threshold for sub-lethal effects found by Krause (1993) in a sea urchin fertilization bioassay. Time averaged dilutions in the far-field are larger by factors of 10 2 to 10 3.

  20. The State, Potential Distribution, and Biological Implications of Methane in the Martian Crust

    NASA Technical Reports Server (NTRS)

    Max, Michael D.; Clifford, Stephen M.

    2000-01-01

    The search for life on Mars has recently focused on its potential survival in deep (>2 km) subpermafrost aquifers where anaerobic bacteria, similar to those found in deep subsurface ecosystems on Earth, may have survived in an environment that has remained stable for billions of years. An anticipated by-product of this biological activity is methane. The detection of large deposits of methane gas and hydrate in the Martian cryosphere, or as emissions from deep fracture zones, would provide persuasive evidence of indigenous life and confirm the presence of a valuable in situ resource for use by future human explorers.

  1. The State, Potential Distribution, and Biological Implications of Methane in the Martian Crust

    NASA Technical Reports Server (NTRS)

    Max, Michael D.; Clifford, Stephen M.

    2000-01-01

    The search for life on Mars has recently focused on its potential survival in deep (>2 km) subpermafrost aquifers where anaerobic bacteria, similar to those found in deep subsurface ecosystems on Earth, may have survived in an environment that has remained stable for billions of years. An anticipated by-product of this biological activity is methane. The detection of large deposits of methane gas and hydrate in the Martian cryosphere, or as emissions from deep fracture zones, would provide persuasive evidence of indigenous life and confirm the presence of a valuable in situ resource for use by future human explorers.

  2. The state, potential distribution, and biological implications of methane in the Martian crust

    NASA Astrophysics Data System (ADS)

    Max, Michael D.; Clifford, Stephen M.

    2000-02-01

    The search for life on Mars has recently focused on its potential survival in deep (>2 km) subpermafrost aquifers where anaerobic bacteria, similar to those found in deep subsurface ecosystems on Earth, may have survived in an environment that has remained stable for billions of years. An anticipated by-product of this biological activity is methane. The detection of large deposits of methane gas and hydrate in the Martian cryosphere, or as emissions from deep fracture zones, would provide persuasive evidence of indigenous life and confirm the presence of a valuable in situ resource for use by future human explorers.

  3. Coastal inshore waters in the NW Mediterranean: Physicochemical and biological characterization and management implications

    NASA Astrophysics Data System (ADS)

    Flo, Eva; Garcés, Esther; Manzanera, Marta; Camp, Jordi

    2011-07-01

    The physicochemical and biological characteristics of coastal waters form a gradient extending from land to ocean. In the Mediterranean this gradient is particularly large, due to the sea's weak tides. Within coastal waters, those waters in contact with land are called coastal inshore waters (CIW), defined herein as between 0 and 200 m from the shoreline. Here we present the first physicochemical and biological characterization of CIW of the NW Mediterranean Sea. This case study is based on 19 years of data collected from coastal inshore (CIW; 0-200 m), nearshore (CNW; 200-1500 m), and offshore (COW; >1500 m) waters of the Catalan coast. Analyses of these data showed that the physicochemical and biological characteristics of CIW differ significantly from those of CNW and COW due to: (1) significantly higher concentrations of dissolved inorganic nutrients (nitrate = 11.07 μM, nitrite = 0.52 μM, ammonium = 6.43 μM, phosphate = 0.92 μM, silicates = 5.99 μM) and chlorophyll- a (=2.42 μg/L) in CIW than in either CNW or COW (in some cases up to one order of magnitude); (2) a greater variability of dissolved inorganic nutrients and chlorophyll- a in CIW than in CNW and COW, and (3) the presence of a mostly urban population and the effects of river inflows as a primary source of CIW variability but with minimal impact on CNW or COW. In addition, the risk of eutrophication was found to be highest in CIW, placing human and environmental interests at greater risk than in the outermost coastal waters. The results highlight the importance of considering the distinctive physicochemical and biological properties of CIW in future coastal waters studies. This is of major importance in assessments of eutrophication and coastal water quality, not only to identify the pressure-impact relationships but also to allow the timely detection of local environmental problems and thus avoid endangering the unique communities of CIW and ensuring the sustainability of human activities. In

  4. New insights in the biology of BDNF synthesis and release: implications in CNS function.

    PubMed

    Greenberg, Michael E; Xu, Baoji; Lu, Bai; Hempstead, Barbara L

    2009-10-14

    BDNF has pleiotropic effects on neuronal development and synaptic plasticity that underlie circuit formation and cognitive function. Recent breakthroughs reveal that neuronal activity regulates BDNF cell biology, including Bdnf transcription, dendritic targeting and trafficking of BDNF mRNA and protein, and secretion and extracellular conversion of proBDNF to mature BDNF. Defects in these mechanisms contribute differentially to cognitive dysfunction and anxiety-like behaviors. Here we review recent studies, presented at a symposium at Neuroscience 2009, that describe regulatory mechanisms that permit rapid and dynamic refinement of BDNF actions in neurons.

  5. Reactions of oxidatively activated arylamines with thiols: reaction mechanisms and biologic implications. An overview.

    PubMed Central

    Eyer, P

    1994-01-01

    Aromatic amines belong to a group of compounds that exert their toxic effects usually after oxidative biotransformation, primarily in the liver. In addition, aromatic amines also undergo extrahepatic activation to yield free arylaminyl radicals. The reactive intermediates are potential promutagens and procarcinogens, and responsible for target tissue toxicity. Since thiols react with these intermediates at high rates, it is of interest to know the underlying reaction mechanisms and the toxicologic implications. Phenoxyl radicals from aminophenols and aminyl radicals from phenylenediamines quickly disproportionate to quinone imines and quinone diimines. Depending on the structure, Michael addition or reduction reactions with thiols may prevail. Products of sequential oxidation/addition reactions (e.g., S-conjugates of aminophenols) are occasionally more toxic than the parent compounds because of their higher autoxidizability and their accumulation in the kidney. Even after covalent binding of quinone imines to protein SH groups, the resulting thioethers are able to autoxidize. The quinoid thioethers can then cross-link the protein by addition to neighboring nucleophiles. The reactions of nitrosoarenes with thiols yield a so-called "semimercaptal" from which various branching reactions detach, depending on substituents. Compounds with strong pi-donors, like 4-nitrosophenetol, give a resonance-stabilized N-(thiol-S-yl)-arylamine cation that may lead to bicyclic products, thioethers, and DNA adducts. Examples of toxicologic implications of the interactions of nitroso compounds with thiols are given for nitrosoimidazoles, heterocyclic nitroso compounds from protein pyrolysates, and nitrosoarenes. These data indicate that interactions of activated arylamines with thiols may not be regarded exclusively as detoxication reactions. PMID:7889834

  6. Interaction of RSU 1069 and 1137 with DNA in vitro. Biological implications and mechanistic aspects.

    PubMed

    Lafleur, M V; Westmijze, E J; Visser, O J; Wagenaar, N; Soetekouw, R; Loman, H; Retèl, J

    1991-06-01

    We have examined the capacity of the nitroimidazole aziridine antitumour drug RSU 1069 to react with DNA in vitro in order to get a better understanding of its mechanism of action. Moreover, we have utilized biologically active phi X174 DNA to investigate the biological relevance of the chemical DNA modification induced by the drug. Incubation of RSU 1069 in the presence of single-stranded phi X174 DNA resulted in extensive inactivation of the DNA, which is dependent on the concentration of drug and temperature. Only about 2% of the inactivating damage can be attributed to strand breakage. The main damage most probably consists of base damage, of which a part is non-lethal and alkali-labile which in turn can be converted into lethal lesion and subsequently into a break applying a post-incubation alkali treatment. Furthermore, from the dependence of the inactivation and also the formation of breaks on pH and ionic strength, it is concluded that the reaction most probably takes place between a protonated RSU 1069 and a negative DNA coil and that the damage pattern reflects the difference in reactivity of RSU 1069 with the phosphate groups and the bases in DNA. Comparison between RSU 1069 and its ring-open hydrolysis product RSU 1137 revealed that (lethal) damage induced in the DNA must be ascribed to the alkylating properties of the aziridine moiety.

  7. Aluminum-Induced Entropy in Biological Systems: Implications for Neurological Disease

    PubMed Central

    Shaw, Christopher A.; Seneff, Stephanie; Kette, Stephen D.; Tomljenovic, Lucija; Oller, John W.; Davidson, Robert M.

    2014-01-01

    Over the last 200 years, mining, smelting, and refining of aluminum (Al) in various forms have increasingly exposed living species to this naturally abundant metal. Because of its prevalence in the earth's crust, prior to its recent uses it was regarded as inert and therefore harmless. However, Al is invariably toxic to living systems and has no known beneficial role in any biological systems. Humans are increasingly exposed to Al from food, water, medicinals, vaccines, and cosmetics, as well as from industrial occupational exposure. Al disrupts biological self-ordering, energy transduction, and signaling systems, thus increasing biosemiotic entropy. Beginning with the biophysics of water, disruption progresses through the macromolecules that are crucial to living processes (DNAs, RNAs, proteoglycans, and proteins). It injures cells, circuits, and subsystems and can cause catastrophic failures ending in death. Al forms toxic complexes with other elements, such as fluorine, and interacts negatively with mercury, lead, and glyphosate. Al negatively impacts the central nervous system in all species that have been studied, including humans. Because of the global impacts of Al on water dynamics and biosemiotic systems, CNS disorders in humans are sensitive indicators of the Al toxicants to which we are being exposed. PMID:25349607

  8. Response of an invasive liana to simulated herbivory: implications for its biological control

    NASA Astrophysics Data System (ADS)

    Raghu, S.; Dhileepan, K.; Treviño, M.

    2006-05-01

    Pre-release evaluation of the efficacy of biological control agents is often not possible in the case of many invasive species targeted for biocontrol. In such circumstances simulating herbivory could yield significant insights into plant response to damage, thereby improving the efficiency of agent prioritisation, increasing the chances of regulating the performance of invasive plants through herbivory and minimising potential risks posed by release of multiple herbivores. We adopted this approach to understand the weaknesses herbivores could exploit, to manage the invasive liana, Macfadyena unguis-cati. We simulated herbivory by damaging the leaves, stem, root and tuber of the plant, in isolation and in combination. We also applied these treatments at multiple frequencies. Plant response in terms of biomass allocation showed that at least two severe defoliation treatments were required to diminish this liana's climbing habit and reduce its allocation to belowground tuber reserves. Belowground damage appears to have negligible effect on the plant's biomass production and tuber damage appears to trigger a compensatory response. Plant response to combinations of different types of damage did not differ significantly to that from leaf damage. This suggests that specialist herbivores in the leaf-feeding guild capable of removing over 50% of the leaf tissue may be desirable in the biological control of this invasive species.

  9. Nonbonding interactions of organic halogens in biological systems: implications for drug discovery and biomolecular design.

    PubMed

    Lu, Yunxiang; Wang, Yong; Zhu, Weiliang

    2010-05-14

    Halogenation is an important approach in lead optimization for drug development and about half of the molecules used in high-throughput screening are halogenated. However, there is neither a suitable theoretical algorithm for evaluating the interaction between the halogen atoms of a ligand and its target protein nor a detailed understanding of how a halogen atom interacts with electron-rich atoms or groups of the residues in the binding pocket. In this Perspective, we concentrate on nonbonding interactions of halogens from both crystallographic data and theoretical viewpoints. It is found that organic halogen atoms are favorably involved in a wide variety of noncovalent protein-ligand interactions, such as halogen bonds C-X...O and hydrogen bonds C-X...H, that show remarkable differences in terms of the geometrical and energetic features. In biological molecules, heavier halogens prefer to form linear interactions with oxygen atoms and aromatic pi systems as compared to N or S, while the mean intermolecular distances for these types of halogen bonds increase with the radius or polarizability of halogen atoms, viz., Cl < Br < I. Furthermore, F...H interactions in protein-ligand complexes exhibit disparate behavior relative to X...H (X = Cl, Br, I) counterparts. These observed tendencies of the interactions involving halogens are subsequently rationalized by means of ab initio calculations using small model systems. The results presented herein should be of great use in the rational design of halogenated ligands as inhibitors and drugs as well as in biological engineering.

  10. Molecular biology in marine science: Scientific questions, technological approaches, and practical implications

    SciTech Connect

    Not Available

    1994-12-31

    The ocean plays an important role in regulating the earth`s climate, sustains a large portion of the earth`s biodiversity, is a tremendous reservoir of commercially important substances, and is used for a variety of often conflicting purposes. In recent decades marine scientists have discovered much about the ocean and its organisms, yet many important fundamental questions remain unanswered. Human populations have increased, particularly in coastal regions. As a result, the marine environment in these areas is increasingly disrupted by human activities, including pollution and the depletion of some ecologically and commercially important species. There is a sense of urgency about reducing human impacts on the ocean and a need to understand how altered ecosystems and the loss of marine species and biodiversity could affect society. This report describes molecular techniques that could be invaluable in addressing process-oriented problems in the ocean sciences that have perplexed oceanographers for decades, such as understanding the basis for biogeochemical processes, recruitment processes, upper-ocean dynamics, biological impacts of global warming, and ecological impacts of human activities. The coupling of highly sophisticated methods, such as satellite remote sensing, which permits synoptic monitoring of chemical, physical, and biological parameters over large areas, with the power of modern molecular tools for ground truthing at small scales could allow scientists to address questions about marine organisms and the ocean in which they live that could not be answered previously.

  11. Mouse models of NPM1-mutated acute myeloid leukemia: biological and clinical implications.

    PubMed

    Sportoletti, P; Varasano, E; Rossi, R; Mupo, A; Tiacci, E; Vassiliou, G; Martelli, M P; Falini, B

    2015-02-01

    Acute myeloid leukemia (AML) carrying nucleophosmin (NPM1) mutations displays distinct biological and clinical features that led to its inclusion as a provisional disease entity in the 2008 World Health Organization (WHO) classification of myeloid neoplasms. Studies of the molecular mechanisms underlying the pathogenesis of NPM1-mutated AML have benefited greatly from several mouse models of this leukemia developed over the past few years. Immunocompromised mice xenografted with NPM1-mutated AML served as the first valuable tool for defining the biology of the disease in vivo. Subsequently, genetically engineered mouse models of the NPM1 mutation, including transgenic and knock-in alleles, allowed the generation of mice with a constant genotype and a reproducible phenotype. These models have been critical for investigating the nature of the molecular effects of these mutations, defining the function of leukemic stem cells in NPM1-mutated AML, identifying chemoresistant preleukemic hemopoietic stem cells and unraveling the key molecular events that cooperate with NPM1 mutations to induce AML in vivo. Moreover, they can serve as a platform for the discovery and validation of new antileukemic drugs in vivo. Advances derived from the analysis of these mouse models promise to greatly accelerate the development of new molecularly targeted therapies for patients with NPM1-mutated AML.

  12. A hybrid biology course: Implications of merging Internet-enhanced and campus-based instructional modes

    NASA Astrophysics Data System (ADS)

    Clark, Sharron Ann

    This is possibly the first study of a hybrid online biology course where WebCT internet-enhanced modes of instruction replaced conventional face-to-face (F2F) lecture materials, merging with collaborative inquiry-based on-campus laboratory instructional modes. Although not a true experiment, the design of this study included three independent cohorts, a pretest and three posttests, as described by Gay and Airasian (2000). This study reported differences in age, gender, number of prior online courses and pretest scores. Over time, persistence, achievement and computer self-efficacy differed in one hybrid online section (N = 31) and two F2F cohorts (N = 29 and 30). One F2F cohort used written test materials and the other used intranet-delivered materials to examine possible differences in groups using electronic assessment modes. In this study, community college students self-selecting into online hybrid and traditional versions of the same biology course did not have the same number of prior online courses, achievement or persistence rates as those self-selecting into F2F sections of the same course with the same laboratories and instructor. This study includes twenty pretest items selected from Instructor's Manual and Test Item File to Accompany: Inquiry into Life, 9th Edition (Schrock, 2000). This study produced 63 tables, 13 figures and 173 references.

  13. Cancer stem cells in hepatocellular carcinoma: Therapeutic implications based on stem cell biology.

    PubMed

    Chiba, Tetsuhiro; Iwama, Atsushi; Yokosuka, Osamu

    2016-01-01

    Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third most frequent cause of cancer-related death worldwide. Despite advances in its diagnosis and treatment, the prognosis of patients with advanced HCC remains unfavorable. Recent advances in stem cell biology and associated technologies have enabled the identification of minor components of tumorigenic cells, termed cancer stem cells (CSC) or tumor-initiating cells, in cancers such as HCC. Furthermore, because CSC play a central role in tumor development, metastasis and recurrence, they are considered to be a therapeutic target in cancer treatment. Hepatic CSC have been successfully identified using functional and cell surface markers. The analysis of purified hepatic CSC has revealed the molecular machinery and signaling pathways involved in their maintenance. In addition, epigenetic transcriptional regulation has been shown to be important in the development and maintenance of CSC. Although inhibitors of CSC show promise as CSC-targeting drugs, novel therapeutic approaches for the eradication of CSC are yet to be established. In this review, we describe recent progress in hepatic CSC research and provide a perspective on the available therapeutic approaches based on stem cell biology. © 2015 The Japan Society of Hepatology.

  14. Obesity and psychiatric disorders: commonalities in dysregulated biological pathways and their implications for treatment.

    PubMed

    Lopresti, Adrian L; Drummond, Peter D

    2013-08-01

    Rates of obesity are higher than normal across a range of psychiatric disorders, including major depressive disorder, bipolar disorder, schizophrenia and anxiety disorders. While the problem of obesity is generally acknowledged in mental health research and treatment, an understanding of their bi-directional relationship is still developing. In this review the association between obesity and psychiatric disorders is summarised, with a specific emphasis on similarities in their disturbed biological pathways; namely neurotransmitter imbalances, hypothalamus-pituitary-adrenal axis disturbances, dysregulated inflammatory pathways, increased oxidative and nitrosative stress, mitochondrial disturbances, and neuroprogression. The applicability and effectiveness of weight-loss interventions in psychiatric populations are reviewed along with their potential efficacy in ameliorating disturbed biological pathways, particularly those mediating inflammation and oxidative stress. It is proposed that weight loss may not only be an effective intervention to enhance physical health but may also improve mental health outcomes and slow the rate of neuroprogressive disturbances in psychiatric disorders. Areas of future research to help expand our understanding of the relationship between obesity and psychiatric disorders are also outlined.

  15. Prosthetic devices: challenges and implications of robotic implants and biological interfaces.

    PubMed

    Lai, J C K; Schoen, M P; Perez Gracia, A; Naidu, D S; Leung, S W

    2007-02-01

    Although among designs of prosthetics there have been some successes in the design of functional robotic implants, there remain many issues and challenges concerned with the failure to meet the 'ideal' requirements of a satisfactory prosthetic. These 'ideals' require the device to be easy to control, comfortable to wear, and cosmetically pleasing. Because the literature on prosthetics and robotic implants are voluminous, this review focuses on four topics to determine key challenges and opportunities underlying these interdisciplinary research areas: firstly, an artificial hand as a biomimetic; secondly, prosthetic implants (electromyography signals and control); thirdly, prosthetic implants and tissue reactions to the material(s) of implants; fourthly, how inflammatory responses of cells and tissues surrounding implanted sensors interfere with the signal transmission of such sensors. This review also notes the importance of the biological interfaces that robotic implants and other prosthetic devices are in contact with and how an improved knowledge of pathophysiological changes at such biological interfaces will lead to improved and more biocompatible designs of prosthetics. This review concludes with the vision that, to develop a design that satisfies the above 'ideals', an interdisciplinary team of biomedical and tissue engineers, and biomaterial and biomedical scientists is needed to work together holistically and synergistically.

  16. Biologic complexity in sickle cell disease: implications for developing targeted therapeutics.

    PubMed

    Gee, Beatrice E

    2013-01-01

    Current therapy for sickle cell disease (SCD) is limited to supportive treatment of complications, red blood cell transfusions, hydroxyurea, and stem cell transplantation. Difficulty in the translation of mechanistically based therapies may be the result of a reductionist approach focused on individual pathways, without having demonstrated their relative contribution to SCD complications. Many pathophysiologic processes in SCD are likely to interact simultaneously to contribute to acute vaso-occlusion or chronic vasculopathy. Applying concepts of systems biology and network medicine, models were developed to show relationships between the primary defect of sickle hemoglobin (Hb S) polymerization and the outcomes of acute pain and chronic vasculopathy. Pathophysiologic processes such as inflammation and oxidative stress are downstream by-products of Hb S polymerization, transduced through secondary pathways of hemolysis and vaso-occlusion. Pain, a common clinical trials endpoint, is also complex and may be influenced by factors outside of sickle cell polymerization and vascular occlusion. Future sickle cell research needs to better address the biologic complexity of both sickle cell disease and pain. The relevance of individual pathways to important sickle cell outcomes needs to be demonstrated in vivo before investing in expensive and labor-intensive clinical trials.

  17. A test of Ockham's razor: implications of conjugated linoleic acid in bone biology.

    PubMed

    Watkins, Bruce A; Li, Yong; Lippman, Hugh E; Reinwald, Susan; Seifert, Mark F

    2004-06-01

    The philosopher William of Ockham is recognized for the maxim that an assumption introduced to explain a phenomenon must not be multiplied beyond necessity, or that the simplest explanation is probably the correct explanation. The general truth is that conjugated linoleic acids (CLAs) are nutrients. However, the demonstration that these isomers of octadecadienoic acid protect against cancers in rodents stimulated curiosity that directed significant resources to characterize the biological functions of these fatty acids in cell and animal models. The benefits to human subjects given supplements of CLA were at best modest. The disappointing results in humans should be taken as an opportunity to critically evaluate all findings of CLA use and to consolidate the common actions of this nutrient so that future investigations focus on specific isomers and the most reasonable mechanisms. As such, the principal and consistently reported benefits of CLA have been in improving cancer outcomes, reducing body fat in growing animals, and modulating cell functions. Recognizing where related actions of CLA converge in specific disease conditions and physiologic states is how research efforts should be directed to minimize the pursuit of superfluous theories. Here, we briefly review the current biological effects of CLA and attempt to integrate their potential effect on the physiology and health of the skeletal system. Thus, the purpose of this review is to advance the science of CLA and to identify areas of research in which these nutrients affect bone metabolism and skeletal health.

  18. Histopathology of Growth Anomaly Affecting the Coral, Montipora capitata: Implications on Biological Functions and Population Viability

    PubMed Central

    Burns, John H. R.; Takabayashi, Misaki

    2011-01-01

    Growth anomalies (GAs) affect the coral, Montipora capitata, at Wai'ōpae, southeast Hawai'i Island. Our histopathological analysis of this disease revealed that the GA tissue undergoes changes which compromise anatomical machinery for biological functions such as defense, feeding, digestion, and reproduction. GA tissue exhibited significant reductions in density of ova (66.1–93.7%), symbiotic dinoflagellates (38.8–67.5%), mesenterial filaments (11.2–29.0%), and nematocytes (28.8–46.0%). Hyperplasia of the basal body wall but no abnormal levels of necrosis and algal or fungal invasion was found in GA tissue. Skeletal density along the basal body wall was significantly reduced in GAs compared to healthy or unaffected sections. The reductions in density of the above histological features in GA tissue were collated with disease severity data to quantify the impact of this disease at the colony and population level. Resulting calculations showed this disease reduces the fecundity of M. capitata colonies at Wai'ōpae by 0.7–49.6%, depending on GA severity, and the overall population fecundity by 2.41±0.29%. In sum, GA in this M. capitata population reduces the coral's critical biological functions and increases susceptibility to erosion, clearly defining itself as a disease and an ecological threat. PMID:22205976

  19. In vitro susceptibility of nematophagous fungi to antiparasitic drugs: interactions and implications for biological control.

    PubMed

    Vieira, J N; Maia, F S; Ferreira, G F; Mendes, J F; Gonçalves, C L; Villela, M M; Pereira, D I B; Nascente, P S

    2016-10-03

    The fast anthelmintic resistance development has shown a limited efficiency in the control of animal's endoparasitosis and has promoted research using alternative control methods. The use of chemicals in animal anthelmintic treatment, in association with nematophagous fungi used for biological control, is a strategy that has proven to be effective in reducing the nematode population density in farm animals. This study aims to verify the in vitro susceptibility of the nematophagous fungi Arthrobotrys oligospora, Duddingtonia flagrans and Paecilomyces lilacinus against the antiparasitic drugs albendazole, thiabendazole, ivermectin, levamisole and closantel by using the Minimum Inhibitory Concentration (MIC). MICs ranged between 4.0 and 0.031 µg/mL for albendazole, thiabendazole and ivermectin, between 0.937 and 0.117 µg/mL for levamisole, and between 0.625 and 0.034 µg/mL for closantel. The results showed that all antiparasitic drugs had an in vitro inhibitory effect on nematophagous fungi, which could compromise their action as agents of biological control. D. flagrans was the most susceptible species to all drugs.

  20. Monodispersed magnetite nanoparticles optimized for magnetic fluid hyperthermia: Implications in biological systems

    NASA Astrophysics Data System (ADS)

    Khandhar, Amit P.; Ferguson, R. Matthew; Krishnan, Kannan M.

    2011-04-01

    Magnetite (Fe3O4) nanoparticles (MNPs) are suitable materials for Magnetic Fluid Hyperthermia (MFH), provided their size is carefully tailored to the applied alternating magnetic field (AMF) frequency. Since aqueous synthesis routes produce polydisperse MNPs that are not tailored for any specific AMF frequency, we have developed a comprehensive protocol for synthesizing highly monodispersed MNPs in organic solvents, specifically tailored for our field conditions (f = 376 kHz, H0 = 13.4 kA/m) and subsequently transferred them to water using a biocompatible amphiphilic polymer. These MNPs (σavg. = 0.175) show truly size-dependent heating rates, indicated by a sharp peak in the specific loss power (SLP, W/g Fe3O4) for 16 nm (diameter) particles. For broader size distributions (σavg. = 0.266), we observe a 30% drop in overall SLP. Furthermore, heating measurements in biological medium [Dulbecco's modified Eagle medium (DMEM) + 10% fetal bovine serum] show a significant drop for SLP (˜30% reduction in 16 nm MNPs). Dynamic Light Scattering (DLS) measurements show particle hydrodynamic size increases over time once dispersed in DMEM, indicating particle agglomeration. Since the effective magnetic relaxation time of MNPs is determined by fractional contribution of the Neel (independent of hydrodynamic size) and Brownian (dependent on hydrodynamic size) components, we conclude that agglomeration in biological medium modifies the Brownian contribution and thus the net heating capacity of MNPs.

  1. Monodispersed magnetite nanoparticles optimized for magnetic fluid hyperthermia: Implications in biological systems.

    PubMed

    Khandhar, Amit P; Ferguson, R Matthew; Krishnan, Kannan M

    2011-04-01

    Magnetite (Fe(3)O(4)) nanoparticles (MNPs) are suitable materials for Magnetic Fluid Hyperthermia (MFH), provided their size is carefully tailored to the applied alternating magnetic field (AMF) frequency. Since aqueous synthesis routes produce polydisperse MNPs that are not tailored for any specific AMF frequency, we have developed a comprehensive protocol for synthesizing highly monodispersed MNPs in organic solvents, specifically tailored for our field conditions (f = 376 kHz, H(0) = 13.4 kA∕m) and subsequently transferred them to water using a biocompatible amphiphilic polymer. These MNPs (σ(avg.) = 0.175) show truly size-dependent heating rates, indicated by a sharp peak in the specific loss power (SLP, W∕g Fe(3)O(4)) for 16 nm (diameter) particles. For broader size distributions (σ(avg.) = 0.266), we observe a 30% drop in overall SLP. Furthermore, heating measurements in biological medium [Dulbecco's modified Eagle medium (DMEM) + 10% fetal bovine serum] show a significant drop for SLP (∼30% reduction in 16 nm MNPs). Dynamic Light Scattering (DLS) measurements show particle hydrodynamic size increases over time once dispersed in DMEM, indicating particle agglomeration. Since the effective magnetic relaxation time of MNPs is determined by fractional contribution of the Neel (independent of hydrodynamic size) and Brownian (dependent on hydrodynamic size) components, we conclude that agglomeration in biological medium modifies the Brownian contribution and thus the net heating capacity of MNPs.

  2. A Theoretical Mechanism of Szilard Engine Function in Nucleic Acids and the Implications for Quantum Coherence in Biological Systems

    SciTech Connect

    Matthew Mihelic, F.

    2010-12-22

    Nucleic acids theoretically possess a Szilard engine function that can convert the energy associated with the Shannon entropy of molecules for which they have coded recognition, into the useful work of geometric reconfiguration of the nucleic acid molecule. This function is logically reversible because its mechanism is literally and physically constructed out of the information necessary to reduce the Shannon entropy of such molecules, which means that this information exists on both sides of the theoretical engine, and because information is retained in the geometric degrees of freedom of the nucleic acid molecule, a quantum gate is formed through which multi-state nucleic acid qubits can interact. Entangled biophotons emitted as a consequence of symmetry breaking nucleic acid Szilard engine (NASE) function can be used to coordinate relative positioning of different nucleic acid locations, both within and between cells, thus providing the potential for quantum coherence of an entire biological system. Theoretical implications of understanding biological systems as such 'quantum adaptive systems' include the potential for multi-agent based quantum computing, and a better understanding of systemic pathologies such as cancer, as being related to a loss of systemic quantum coherence.

  3. Elevated reward-related neural activation as a unique biological marker of bipolar disorder: assessment and treatment implications.

    PubMed

    Nusslock, Robin; Young, Christina B; Damme, Katherine S F

    2014-11-01

    Growing evidence indicates that risk for bipolar disorder is characterized by elevated activation in a fronto-striatal reward neural circuit involving the ventral striatum and orbitofrontal cortex, among other regions. It is proposed that individuals with abnormally elevated reward-related neural activation are at risk for experiencing an excessive increase in approach-related motivation during life events involving rewards or goal striving and attainment. In the extreme, this increase in motivation is reflected in hypomanic/manic symptoms. By contrast, unipolar depression (without a history of hypomania/mania) is characterized by decreased reward responsivity and decreased reward-related neural activation. Collectively, this suggests that risk for bipolar disorder and unipolar depression are characterized by distinct and opposite profiles of reward processing and reward-related neural activation. The objective of the present paper is threefold. First, we review the literature on reward processing and reward-related neural activation in bipolar disorder, and in particular risk for hypomania/mania. Second, we propose that reward-related neural activation reflects a biological marker of differential risk for bipolar disorder versus unipolar depression that may help facilitate psychiatric assessment and differential diagnosis. We also discuss, however, the challenges to using neuroscience techniques and biological markers in a clinical setting for assessment and diagnostic purposes. Lastly, we address the pharmacological and psychosocial treatment implications of research on reward-related neural activation in bipolar disorder.

  4. A Theoretical Mechanism of Szilard Engine Function in Nucleic Acids and the Implications for Quantum Coherence in Biological Systems

    NASA Astrophysics Data System (ADS)

    Matthew Mihelic, F.

    2010-12-01

    Nucleic acids theoretically possess a Szilard engine function that can convert the energy associated with the Shannon entropy of molecules for which they have coded recognition, into the useful work of geometric reconfiguration of the nucleic acid molecule. This function is logically reversible because its mechanism is literally and physically constructed out of the information necessary to reduce the Shannon entropy of such molecules, which means that this information exists on both sides of the theoretical engine, and because information is retained in the geometric degrees of freedom of the nucleic acid molecule, a quantum gate is formed through which multi-state nucleic acid qubits can interact. Entangled biophotons emitted as a consequence of symmetry breaking nucleic acid Szilard engine (NASE) function can be used to coordinate relative positioning of different nucleic acid locations, both within and between cells, thus providing the potential for quantum coherence of an entire biological system. Theoretical implications of understanding biological systems as such "quantum adaptive systems" include the potential for multi-agent based quantum computing, and a better understanding of systemic pathologies such as cancer, as being related to a loss of systemic quantum coherence.

  5. Molecular Biology of Human Herpesvirus 8: Novel Functions and Virus–Host Interactions Implicated in Viral Pathogenesis and Replication

    PubMed Central

    Cousins, Emily; Nicholas, John

    2014-01-01

    Human herpesvirus 8 (HHV-8), also known as Kaposi’s sarcoma-associated herpesvirus (KSHV), is the second identified human gammaherpesvirus. Like its relative Epstein-Barr virus, HHV-8 is linked to B-cell tumors, specifically primary effusion lymphoma and multicentric Castleman’s disease, in addition to endothelial-derived KS. HHV-8 is unusual in its possession of a plethora of “accessory” genes and encoded proteins in addition to the core, conserved herpesvirus and gammaherpesvirus genes that are necessary for basic biological functions of these viruses. The HHV-8 accessory proteins specify not only activities deducible from their cellular protein homologies but also novel, unsuspected activities that have revealed new mechanisms of virus–host interaction that serve virus replication or latency and may contribute to the development and progression of virus-associated neoplasia. These proteins include viral interleukin-6 (vIL-6), viral chemokines (vCCLs), viral G protein–coupled receptor (vGPCR), viral interferon regulatory factors (vIRFs), and viral antiapoptotic proteins homologous to FLICE (FADD-like IL-1β converting enzyme)-inhibitory protein (FLIP) and survivin. Other HHV-8 proteins, such as signaling membrane receptors encoded by open reading frames K1 and K15, also interact with host mechanisms in unique ways and have been implicated in viral pathogenesis. Additionally, a set of micro-RNAs encoded by HHV-8 appear to modulate expression of multiple host proteins to provide conditions conducive to virus persistence within the host and could also contribute to HHV-8-induced neoplasia. Here, we review the molecular biology underlying these novel virus–host interactions and their potential roles in both virus biology and virus-associated disease. PMID:24008302

  6. Molecular biology of human herpesvirus 8: novel functions and virus-host interactions implicated in viral pathogenesis and replication.

    PubMed

    Cousins, Emily; Nicholas, John

    2014-01-01

    Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), is the second identified human gammaherpesvirus. Like its relative Epstein-Barr virus, HHV-8 is linked to B-cell tumors, specifically primary effusion lymphoma and multicentric Castleman's disease, in addition to endothelial-derived KS. HHV-8 is unusual in its possession of a plethora of "accessory" genes and encoded proteins in addition to the core, conserved herpesvirus and gammaherpesvirus genes that are necessary for basic biological functions of these viruses. The HHV-8 accessory proteins specify not only activities deducible from their cellular protein homologies but also novel, unsuspected activities that have revealed new mechanisms of virus-host interaction that serve virus replication or latency and may contribute to the development and progression of virus-associated neoplasia. These proteins include viral interleukin-6 (vIL-6), viral chemokines (vCCLs), viral G protein-coupled receptor (vGPCR), viral interferon regulatory factors (vIRFs), and viral antiapoptotic proteins homologous to FLICE (FADD-like IL-1β converting enzyme)-inhibitory protein (FLIP) and survivin. Other HHV-8 proteins, such as signaling membrane receptors encoded by open reading frames K1 and K15, also interact with host mechanisms in unique ways and have been implicated in viral pathogenesis. Additionally, a set of micro-RNAs encoded by HHV-8 appear to modulate expression of multiple host proteins to provide conditions conducive to virus persistence within the host and could also contribute to HHV-8-induced neoplasia. Here, we review the molecular biology underlying these novel virus-host interactions and their potential roles in both virus biology and virus-associated disease.

  7. Physical and biological response of the Arabian Sea to tropical cyclone Phyan and its implications.

    PubMed

    Byju, P; Prasanna Kumar, S

    2011-06-01

    The response to the tropical cyclone Phyan, which developed in the eastern Arabian Sea during 9-11 November 2009, was rapid cooling of sea surface temperature (SST), enhancement of chlorophyll a and two-fold increase in net primary productivity (NPP). Cooling of SST was immediate in response to the strong wind-mixing, and the subsequent upward Ekman pumping sustained the cooling even after the dissipation of Phyan. The biological response mediated by the upward Ekman pumping driven vertical transport of subsurface nutrient showed a time lag of 3-4 days. The CO₂ flux to the atmosphere associated with Phyan was 0.123 Tg C, which accounted for ~85% of the total out-gassing from the eastern Arabian Sea during November. Thus, an increased occurrence of cyclones in a warming environment will lead to an enhanced biomass production and also increase in CO₂ out-gassing.

  8. The Chemical Biology of Molecular Chaperones--Implications for Modulation of Proteostasis.

    PubMed

    Brandvold, Kristoffer R; Morimoto, Richard I

    2015-09-11

    Protein homeostasis (proteostasis) is inextricably tied to cellular health and organismal lifespan. Aging, exposure to physiological and environmental stress, and expression of mutant and metastable proteins can cause an imbalance in the protein-folding landscape, which results in the formation of non-native protein aggregates that challenge the capacity of the proteostasis network (PN), increasing the risk for diseases associated with misfolding, aggregation, and aberrant regulation of cell stress responses. Molecular chaperones have central roles in each of the arms of the PN (protein synthesis, folding, disaggregation, and degradation), leading to the proposal that modulation of chaperone function could have therapeutic benefits for the large and growing family of diseases of protein conformation including neurodegeneration, metabolic diseases, and cancer. In this review, we will discuss the current strategies used to tune the PN through targeting molecular chaperones and assess the potential of the chemical biology of proteostasis. Copyright © 2015. Published by Elsevier Ltd.

  9. Ligand Activation of TAM Family Receptors-Implications for Tumor Biology and Therapeutic Response

    PubMed Central

    Davra, Viralkumar; Kimani, Stanley G.; Calianese, David; Birge, Raymond B.

    2016-01-01

    The TAM family of receptors (i.e., Tyro3, Axl, and Mertk), and their ligands Growth arrest specific factor 6 (Gas6) and Protein S (Pros1) contribute to several oncogenic processes, such as cell survival, invasion, migration, chemo-resistance, and metastasis, whereby expression often correlates with poor clinical outcomes. In recent years, there has been great interest in the study of TAM receptors in cancer, stemming both from their roles as oncogenic signaling receptors, as well as their roles in tumor immunology. As a result, several classes of TAM inhibitors that include small molecule tyrosine kinase inhibitors, monoclonal antibodies, decoy receptors, as well as novel strategies to target TAM ligands are being developed. This paper will review the biology of TAM receptors and their ligands with a focus on cancer, as well as evidence-based data for the continued pursuit of TAM/Gas6 inhibitors in clinical practice. PMID:27916840

  10. The emerging biology of muscle stem cells: implications for cell-based therapies.

    PubMed

    Bentzinger, C Florian; Wang, Yu Xin; von Maltzahn, Julia; Rudnicki, Michael A

    2013-03-01

    Cell-based therapies for degenerative diseases of the musculature remain on the verge of feasibility. Myogenic cells are relatively abundant, accessible, and typically harbor significant proliferative potential ex vivo. However, their use for therapeutic intervention is limited due to several critical aspects of their complex biology. Recent insights based on mouse models have advanced our understanding of the molecular mechanisms controlling the function of myogenic progenitors significantly. Moreover, the discovery of atypical myogenic cell types with the ability to cross the blood-muscle barrier has opened exciting new therapeutic avenues. In this paper, we outline the major problems that are currently associated with the manipulation of myogenic cells and discuss promising strategies to overcome these obstacles.

  11. HNS+ and HSN+ cations: Electronic states, spin-rovibronic spectroscopy with planetary and biological implications

    NASA Astrophysics Data System (ADS)

    Trabelsi, Tarek; Ben Yaghlane, Saida; Al Mogren, Muneerah Mogren; Francisco, Joseph S.; Hochlaf, Majdi

    2016-08-01

    Ab initio methods in conjunction with a large basis set are used to compute the potential energy surfaces of the 12 lowest electronic states of the HNS+ and HSN+ isomeric forms. These potentials are used in discussions of the metastability of these cations and plausible mechanisms for the H+/H + SN+/SN, S/S+ + NH+/NH, N/N+ + SH+/SH ion-molecule reactions. Interestingly, the low rovibrational levels of HSN+(12A″) and HNS+(12A″) electronically excited ions are predicted to be long-lived. Both ions are suggested to be a suitable candidate for light-sensitive NOṡ donor in vivo and as a possible marker for the detection of intermediates in nitrites + H2S reactions at the cellular level. The full spin rovibronic levels of HNS+ are presented, which may assist in the experimental identification of HNS+ and HSN+ ions and in elucidating their roles in astrophysical and biological media.

  12. Structure and Bonding in Heme-Nitrosyl Complexes and Implications for Biology

    SciTech Connect

    Lehnert, Nicolai; Scheidt, W. Robert; Wolf, Matthew W.

    2016-09-13

    This review summarizes our current understanding of the geometric and electronic structures of ferrous and ferric heme–nitrosyls, which are of key importance for the biological functions and transformations of NO. In-depth correlations are made between these properties and the reactivities of these species. Here, a focus is put on the discoveries that have been made in the last 10 years, but previous findings are also included as necessary. Besides this, ferrous heme–nitroxyl complexes are also considered, which have become of increasing interest recently due to their roles as intermediates in NO and multiheme nitrite reductases, and because of the potential role of HNO as a signaling molecule in mammals. In recent years, computational methods have received more attention as a means of investigating enzyme reaction mechanisms, and some important findings from these theoretical studies are also highlighted in this chapter.

  13. Physicochemical properties of crystalline silica dusts and their possible implication in various biological responses.

    PubMed

    Fubini, B; Bolis, V; Cavenago, A; Volante, M

    1995-01-01

    The effect of grinding, heating, and etching was investigated on polymorphs of silicon dioxide exhibiting different biological responses. Diatomaceous earths were converted into cristobalite at 1000 degrees C. Dusts obtained by grinding crystalline minerals exhibited different micromorphology and a propensity to originate surface radicals which decrease in the sequence cristobalite --> quartz --> coesite --> stishovite. The production of surface radicals was suppressed by grinding in the presence of water. Thermal treatments selectively quenched the radicals and decreased surface hydrophilicity. Quartz treated with aluminum lactate exhibited higher surface acidity when compared with pure quartz, with a reduction in fibrogenicity. Etching by hydrofluoric acid smoothed the particles with loss of specific surface. Adsorption of water on three cristobalite dusts of different origin (ground mineral, ex-diatomite, heated quartz) indicated a loss in heated quartz (1300 degrees C) that was relatable to the corresponding reduction in fibrogenicity.

  14. The emerging biology of muscle stem cells: Implications for cell-based therapies

    PubMed Central

    Bentzinger, C Florian; Wang, Yu Xin; von Maltzahn, Julia; Rudnicki, Michael A

    2013-01-01

    Cell-based therapies for degenerative diseases of the musculature remain on the verge of feasibility. Myogenic cells are relatively abundant, accessible, and typically harbor significant proliferative potential ex vivo. However, their use for therapeutic intervention is limited due to several critical aspects of their complex biology. Recent insights based on mouse models have advanced our understanding of the molecular mechanisms controlling the function of myogenic progenitors significantly. Moreover, the discovery of atypical myogenic cell types with the ability to cross the blood-muscle barrier has opened exciting new therapeutic avenues. In this paper, we outline the major problems that are currently associated with the manipulation of myogenic cells and discuss promising strategies to overcome these obstacles. PMID:22886714

  15. Dynamic models of biological pattern formation have some surprising implications for understanding the epigenetics of development.

    PubMed

    Molenaar, Peter C M; Lo, Lawrence

    2013-01-01

    Nonlinear epigenetic processes are conceived of in terms of self-organizing dynamic models of biological pattern formation. Epigenetic processes thus conceived generate substantial subject-specific structural variation, for instance, in growing brain networks. It is shown that standard quantitative genetic modeling based on analyses of interindividual phenotypic variation misclassifies the variation generated by nonlinear epigenetic processes as being due to specific environmental influences. A new quantitative genetic model, iFACE, is introduced to correctly identify the structural variation generated by self-organizing epigenetic processes. iFACE is based on time series analysis of intraindividual variation of a single pair of genetically related subjects. The results of an application of iFACE to multilead EEG obtained with a single dizygotic twin pair is presented.

  16. Cancer-Specific Telomerase Reverse Transcriptase (TERT) Promoter Mutations: Biological and Clinical Implications

    PubMed Central

    Liu, Tiantian; Yuan, Xiaotian; Xu, Dawei

    2016-01-01

    The accumulated evidence has pointed to a key role of telomerase in carcinogenesis. As a RNA-dependent DNA polymerase, telomerase synthesizes telomeric DNA at the end of linear chromosomes, and attenuates or prevents telomere erosion associated with cell divisions. By lengthening telomeres, telomerase extends cellular life-span or even induces immortalization. Consistent with its functional activity, telomerase is silent in most human normal somatic cells while active only in germ-line, stem and other highly proliferative cells. In contrast, telomerase activation widely occurs in human cancer and the enzymatic activity is detectable in up to 90% of malignancies. Recently, hotspot point mutations in the regulatory region of the telomerase reverse transcriptase (TERT) gene, encoding the core catalytic component of telomerase, was identified as a novel mechanism to activate telomerase in cancer. This review discusses the cancer-specific TERT promoter mutations and potential biological and clinical significances. PMID:27438857

  17. The biology of how circumcision reduces HIV susceptibility: broader implications for the prevention field.

    PubMed

    Prodger, Jessica L; Kaul, Rupert

    2017-09-12

    Circumcision reduces heterosexual HIV-1 acquisition in men by at least 60%. However, the biological mechanisms by which circumcision is protective remain incompletely understood. We test the hypothesis that the sub-preputial microenvironment created by the foreskin drives immune activation in adjacent foreskin tissues, facilitating HIV-1 infection through a combination of epithelial barrier disruption, enhanced dendritic cell maturation, and the recruitment/activation of neutrophils and susceptible CD4 T cell subsets such as Th17 cells. Furthermore, we provide evidence that the genital microbiome may be an important driver of this immune activation. This suggests that new modalities to reduce genital immune activation and/or alter the genital microbiome, used alone or in combination with topical microbicides, may be of significant benefit to HIV prevention.

  18. Grades and Withdrawal Rates in Cell Biology and Genetics Based upon Institution Type for General Biology and Implications for Transfer Articulation Agreements

    ERIC Educational Resources Information Center

    Regier, Kimberly Fayette

    2016-01-01

    General biology courses (for majors) are often transferred from one institution to another. These courses must prepare students for upper division courses in biology. In Colorado, a Biology Transfer Articulation Agreement that includes general biology has been created across the state. An evaluation was conducted of course grades in two upper…

  19. Grades and Withdrawal Rates in Cell Biology and Genetics Based upon Institution Type for General Biology and Implications for Transfer Articulation Agreements

    ERIC Educational Resources Information Center

    Regier, Kimberly Fayette

    2016-01-01

    General biology courses (for majors) are often transferred from one institution to another. These courses must prepare students for upper division courses in biology. In Colorado, a Biology Transfer Articulation Agreement that includes general biology has been created across the state. An evaluation was conducted of course grades in two upper…

  20. Biology and clinical implications of CD133{sup +} liver cancer stem cells

    SciTech Connect

    Ma, Stephanie

    2013-01-15

    Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver, accounting for 80%–90% of all liver cancers. The disease ranks as the fifth most common cancer worldwide and is the third leading cause of all cancer-associated deaths. Although advances in HCC detection and treatment have increased the likelihood of a cure at early stages of the disease, HCC remains largely incurable because of late presentation and tumor recurrence. Only 25% of HCC patients are deemed suitable for curative treatment, with the overall survival at just a few months for inoperable patients. Apart from surgical resection, loco-regional ablation and liver transplantation, current treatment protocols include conventional cytotoxic chemotherapy. But due to the highly resistant nature of the disease, the efficacy of the latter regimen is limited. The recent emergence of the cancer stem cell (CSC) concept lends insight into the explanation of why treatment with chemotherapy often may seem to be initially successful but results in not only a failure to eradicate the tumor but also possibly tumor relapse. Commonly used anti-cancer drugs in HCC work by targeting the rapidly proliferating and differentiated liver cancer cells that constitute the bulk of the tumor. However, a subset of CSCs exists within the tumor, which are more resistant and are able to survive and maintain residence after treatment, thus, growing and self-renewing to generate the development and spread of recurrent tumors in HCC. In the past few years, compelling evidence has emerged in support of the hierarchic CSC model for solid tumors, including HCC. And in particular, CD133 has drawn significant attention as a critical liver CSC marker. Understanding the characteristics and function of CD133{sup +} liver CSCs has also shed light on HCC management and treatment, including the implications for prognosis, prediction and treatment resistance. In this review, a detailed summary of the recent progress

  1. Multifunctional liposomes interact with Abeta in human biological fluids: Therapeutic implications for Alzheimer's disease.

    PubMed

    Conti, Elisa; Gregori, Maria; Radice, Isabella; Da Re, Fulvio; Grana, Denise; Re, Francesca; Salvati, Elisa; Masserini, Massimo; Ferrarese, Carlo; Zoia, Chiara Paola; Tremolizzo, Lucio

    2017-02-23

    The accumulation of extracellular amyloid beta (Abeta42) both in brain and in cerebral vessels characterizes Alzheimer's disease (AD) pathogenesis. Recently, the possibility to functionalize nanoparticles (NPs) surface with Abeta42 binding molecules, making them suitable tools for reducing Abeta42 burden has been shown effective in models of AD. Aim of this work consisted in proving that NPs might be effective in sequestering Abeta42 in biological fluids, such as CSF and plasma. This demonstration is extremely important considering that these Abeta42 pools are in continuum with the brain parenchyma with drainage of Abeta from interstitial brain tissue to blood vessel and plasma. In this work, liposomes (LIP) were functionalized as previously shown in order to promote high-affinity Abeta binding, i.e., either with, phosphatidic acid (PA), or a modified Apolipoprotein E-derived peptide (mApo), or with a curcumin derivative (TREG); Abeta42 levels were determined by ELISA in CSF and plasma samples. mApo-PA-LIP (25 and 250 μM) mildly albeit significantly sequestered Abeta42 proteins in CSF samples obtained from healthy subjects (p < 0.01). Analogously a significant binding (∼20%) of Abeta42 (p < 0.001) was demonstrated following exposure to all functionalized liposomes in plasma samples obtained from selected AD or Down's syndrome patients expressing high levels of Abeta42. The same results were obtained by quantifying Abeta42 content after removal of liposome-bound Abeta by using gel filtration chromatography or ultracentrifugation on a discontinuous sucrose density gradient. In conclusion, we demonstrate that functionalized liposomes significantly sequester Abeta42 in human biological fluids. These data may be critical for future in vivo administration tests using NPs for promoting sink effect.

  2. Differentiation between osteoarthritis and psoriatic arthritis: implications for pathogenesis and treatment in the biologic therapy era

    PubMed Central

    Hermann, Kay-Geert A.; Tan, Ai Lyn

    2015-01-01

    Rheumatologists have long considered OA and PsA as two completely distinct arthropathies. This review highlights how some forms of generalized OA and PsA may afflict the same entheseal-associated anatomical territories. While degeneration or inflammation may be clearly discernible at the two extremes, there may be a group of patients where differentiation is impossible. Misdiagnosis of a primary degeneration-related pathology as being part of the PsA spectrum could lead to apparent failure of disease-modifying agents, including apparent anti-TNF and apparent IL23/17 axis therapy failure. This is not a reflection of poor clinical acumen, but rather a failure to appreciate that the pathological process overlaps in the two diseases. Whether the category of OA–PsA overlap disease exists or whether it represents the co-occurrence of two common arthropathies that afflict the same anatomical territories has implications for the optimal diagnosis and management of both OA and PsA. PMID:25231177

  3. Cancer Stem Cells and Macrophages: Implications in Tumor Biology and Therapeutic Strategies

    PubMed Central

    Sainz, Bruno; Carron, Emily; Vallespinós, Mireia; Machado, Heather L.

    2016-01-01

    Cancer stem cells (CSCs) are a unique subset of cells within tumors with stemlike properties that have been proposed to be key drivers of tumor initiation and progression. CSCs are functionally defined by their unlimited self-renewal capacity and their ability to initiate tumor formation in vivo. Like normal stem cells, CSCs exist in a cellular niche comprised of numerous cell types including tumor-associated macrophages (TAMs) which provides a unique microenvironment to protect and promote CSC functions. TAMs provide pivotal signals to promote CSC survival, self-renewal, maintenance, and migratory ability, and in turn, CSCs deliver tumor-promoting cues to TAMs that further enhance tumorigenesis. Studies in the last decade have aimed to understand the molecular mediators of CSCs and TAMs, and recent advances have begun to elucidate the complex cross talk that occurs between these two cell types. In this review, we discuss the molecular interactions that define CSC-TAM cross talk at each stage of tumor progression and examine the clinical implications of targeting these interactions. PMID:26980947

  4. Epidemiological Implications of Host Biodiversity and Vector Biology: Key Insights from Simple Models.

    PubMed

    Dobson, Andrew D M; Auld, Stuart K J R

    2016-04-01

    Models used to investigate the relationship between biodiversity change and vector-borne disease risk often do not explicitly include the vector; they instead rely on a frequency-dependent transmission function to represent vector dynamics. However, differences between classes of vector (e.g., ticks and insects) can cause discrepancies in epidemiological responses to environmental change. Using a pair of disease models (mosquito- and tick-borne), we simulated substitutive and additive biodiversity change (where noncompetent hosts replaced or were added to competent hosts, respectively), while considering different relationships between vector and host densities. We found important differences between classes of vector, including an increased likelihood of amplified disease risk under additive biodiversity change in mosquito models, driven by higher vector biting rates. We also draw attention to more general phenomena, such as a negative relationship between initial infection prevalence in vectors and likelihood of dilution, and the potential for a rise in density of infected vectors to occur simultaneously with a decline in proportion of infected hosts. This has important implications; the density of infected vectors is the most valid metric for primarily zoonotic infections, while the proportion of infected hosts is more relevant for infections where humans are a primary host.

  5. Acute Myeloid Leukemia with the t(8;21) Translocation: Clinical Consequences and Biological Implications

    PubMed Central

    Reikvam, Håkon; Hatfield, Kimberley Joanne; Kittang, Astrid Olsnes; Hovland, Randi; Bruserud, Øystein

    2011-01-01

    The t(8;21) abnormality occurs in a minority of acute myeloid leukemia (AML) patients. The translocation results in an in-frame fusion of two genes, resulting in a fusion protein of one N-terminal domain from the AML1 gene and four C-terminal domains from the ETO gene. This protein has multiple effects on the regulation of the proliferation, the differentiation, and the viability of leukemic cells. The translocation can be detected as the only genetic abnormality or as part of more complex abnormalities. If t(8;21) is detected in a patient with bone marrow pathology, the diagnosis AML can be made based on this abnormality alone. t(8;21) is usually associated with a good prognosis. Whether the detection of the fusion gene can be used for evaluation of minimal residual disease and risk of leukemia relapse remains to be clarified. To conclude, detection of t(8;21) is essential for optimal handling of these patients as it has both diagnostic, prognostic, and therapeutic implications. PMID:21629739

  6. The shape of the spatial kernel and its implications for biological invasions in patchy environments.

    PubMed

    Lindström, Tom; Håkansson, Nina; Wennergren, Uno

    2011-05-22

    Ecological and epidemiological invasions occur in a spatial context. We investigated how these processes correlate to the distance dependence of spread or dispersal between spatial entities such as habitat patches or epidemiological units. Distance dependence is described by a spatial kernel, characterized by its shape (kurtosis) and width (variance). We also developed a novel method to analyse and generate point-pattern landscapes based on spectral representation. This involves two measures: continuity, which is related to autocorrelation and contrast, which refers to variation in patch density. We also analysed some empirical data where our results are expected to have implications, namely distributions of trees (Quercus and Ulmus) and farms in Sweden. Through a simulation study, we found that kernel shape was not important for predicting the invasion speed in randomly distributed patches. However, the shape may be essential when the distribution of patches deviates from randomness, particularly when the contrast is high. We conclude that the speed of invasions depends on the spatial context and the effect of the spatial kernel is intertwined with the spatial structure. This implies substantial demands on the empirical data, because it requires knowledge of shape and width of the spatial kernel, and spatial structure.

  7. Removal of polar UV stabilizers in biological wastewater treatments and ecotoxicological implications.

    PubMed

    Molins-Delgado, Daniel; Díaz-Cruz, M Silvia; Barceló, Damià

    2015-01-01

    The present study describes the development, validation and application of a fully automated analytical method based on on-line solid-phase extraction-liquid chromatography-tandem mass spectrometry (on line SPE-HPLC-MS/MS) to assess the removal efficiency in water works and the ecotoxicological implications derived of the two most used benzotriazole-class UV stabilizers (BZTs), namely 1H-benzotriazole (BZT) and 5-methyl-1H-benzotriazole (MeBZT). Influent and effluent wastewater samples from 20 wastewater treatment plants (WWTPs) were analyzed. Removal rates (RE%) and half-lives (t1/2) for each BZTs were calculated and correlated to the hydraulic retention time (HRT) of each plant. Both BZTs were detected in all influent and effluent samples (concentrations in the range 26.7 ng L(-1)-42.9 μg L(-1)), with the highest concentrations corresponding to MeBZT. Results indicated that both compounds were recalcitrant (RE% in the range 11.8-94.7%) and that no clear influence of HRT on removals could be drawn. Finally, the potential environmental risk posed by the levels of BZTs detected was evaluated calculating the hazard quotients (HQs) MeBZT was the only BZTs posing a risk to Vibrio fischeri, Daphnia galeata and Pimephales promelas.

  8. Biologic diversity of polyomavirus BK genomic sequences: Implications for molecular diagnostic laboratories.

    PubMed

    Luo, C; Bueno, M; Kant, J; Randhawa, P

    2008-10-01

    Data on polyomavirus genomic diversity has greatly expanded in the past few years. The implications of viral DNA sequence variation on the performance of molecular diagnostic assays have not been systematically examined. 716 BK, 1626 JC, and 73 SV40 virus sequences available in GenBank were aligned using Clustal-X. Five different published BKV PCR assays currently in use at major medical centers were evaluated for primer and probe mismatches with available GenBank sequences. Coverage of naturally occurring BKV strains varied amongst different assay methods. Targeted viral sequences showed major mismatch with primer or probe sequence in up to 30.7% of known BKV strains. BKV subtypes IVa, IVb, and IVc were more prone to this problem, reflecting common use of Type I Dun sequence for assay design. Despite the known polymorphism of this gene, 484 VP-1 sequences with conserved areas potentially suitable for PCR assay design are available. Assay targets in the Large T-antigen and agnogene are less subject to genetic variation, but sequence information corresponding to the latter two genes is available only for 164 and 174 published strains, respectively. Cross reactivity of appropriately selected BKV primers with JCV and SV40 sequences available in current databases was not a significant problem.

  9. A dynamic oral cancer field: unraveling the underlying biology and its clinical implication.

    PubMed

    Tsui, Ivy F L; Garnis, Cathie; Poh, Catherine F

    2009-11-01

    Oral cancer is a complex disease that is characterized by histologic and genetic heterogeneity. The evolution and progression of this disease is thought to result from the accumulation of alterations in molecular pathways. Although the oral cavity is accessible for routine screening of suspicious lesions, gene alterations are known to accrue in histologically normal tissues. Therefore, some cancer forerunners may remain undetected clinically or histologically. Recently emerging optical and molecular technologies have provided a powerful means for redefining the extent of the field of alteration. Often this means expanding upon regions detectable with standard white light approaches. In this report, we used a newly developed optical technique, direct fluorescence visualization, to define a contiguous field that extended beyond the margins of a clinically visible oral squamous cell carcinoma. Multiple biopsies were taken within this contiguous optically altered field. Genome alterations detected for each specimen were compared to define whether each lesion arose independently or as a consequence of a shared progenitor cell. Our results indicate that the field effect of oral cancer is extremely dynamic, with different genetic alterations present in different biopsies within a field. This case study also demonstrated that 2 genetically unrelated squamous cell carcinoma could be developed within 10 mm at the right lateral tongue of this patient. These findings provide evidence for the importance to implement optical technologies in defining surgical margins and support the use of whole genome technologies in the diagnosis of clonal versus independent lesions of the oral cavity, which may have implications on treatment strategies.

  10. Variations in biological characteristics of temperate gonochoristic species of Platycephalidae and their implications: A review

    NASA Astrophysics Data System (ADS)

    Coulson, Peter G.; Hall, Norman G.; Potter, Ian C.

    2017-05-01

    This review provides a composite account of the biological characteristics of the temperate gonochoristic species of the Platycephalidae. Initially, data were obtained for the five abundant platycephalid species in south-western Australia, which each came from either over bare substrata or seagrass and from either estuaries, marine coastal waters or marine embayments. The von Bertalanffy growth curves for females and males of each species differed significantly, with females having a greater TL∞ and lower growth coefficient k. From tests using their upper deciles, the total length (TL) attained by the largest females of each species was significantly greater than that of their males, whereas such a trend did not occur with age. The ratio of females to males in each abundant age class, and overall, exceeded parity for four of the five species (typically P < 0.001) and increased with increasing TL. Mortality estimates, which were similar for each sex of each species, suggest that Platycephalus speculator has been substantially exploited in a seasonally-closed estuary in which it completes its whole life cycle. The above and other biological data for the five species were collated with those published previously for two of those species and five other platycephalid species in south-eastern Australia and one in Japan and another in the Suez Canal, yielding the following conclusions for gonochoristic species of the Platycephalidae. Females attain a larger size than males, the extent varying markedly among species, whereas the longevities of the two sexes of each platycephalid species are similar. The maximum TLs and ages of the various species range widely, with values for females, for example, extending from 221 mm for Ambiserrula jugosa to 985 mm for Platycephalus fuscus and from four years for A. jugosa to 26 years for Platycephalus conatus. The overall ratio of females to males is positively related to the extent to which both the maximum TLs and TL∞s of the

  11. Twenty years of invasion: a review of round goby Neogobius melanostomus biology, spread and ecological implications.

    PubMed

    Kornis, M S; Mercado-Silva, N; Vander Zanden, M J

    2012-02-01

    are presented; most pressing are evaluating the economic effects of N. melanostomus invasion, determining long-term population level effects of egg predation on game-fish recruitment and comparing several variables (density, ecological effects morphology and life history) among invaded ecosystems. This review provides a central reference as researchers continue studying N. melanostomus, often as examples for advancing basic ecology and invasion biology. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  12. A Case of SAPHO Syndrome with Endodontic Implications and Treatment with Biologic Drugs.

    PubMed

    Cotti, Elisabetta; Careddu, Roberto; Schirru, Elia; Marongiu, Silvia; Barca, Maria Pina; Manconi, Paolo Emilio; Mercuro, Giuseppe

    2015-09-01

    SAPHO syndrome (SS) is an autoinflammatory disease characterized by synovitis, acne, pustulosis, hyperostosis, and osteitis. Among the sites affected by the osteoarticular manifestations of SS are the anterior chest wall and the mandible. The etiology of SS is still unknown; theories advocate a genetic predisposition and an infectious cause in association with disorders of the immune system. We report a case of SS in which there was the involvement of the mandible with a lesion of endodontic origin. A 44-year-old white woman diagnosed with SS at the university hospital was referred to the Department of Conservative Dentistry and Endodontics for a consultation. She reported spontaneous pain localized to the periapical area of tooth #19 with a history of multiple restorative and endodontic treatments. It was diagnosed as a previously treated tooth with symptomatic apical periodontitis (AP) at the time of the endodontic evaluation. A second retreatment was then performed in 1 appointment under local anesthesia. During retreatment, a separated instrument and a ledge were found in the mesiobuccal canal, and attempts to bypass it were not successful; the canal was then obturated to the reachable length. Within the same month, the patient was also administered an anti-tumor necrosis factor alpha biologic medication in association with a disease-modifying antirheumatic drugs for the treatment of SS. Within 3 months, the overall therapy had led to a marked improvement of the systemic and mandibular symptoms, and a periapical radiograph showed almost complete healing of the lesion. Medical examinations have shown a total remission of signs and symptoms starting 6 months after the initiation of treatment. After 5 years, the disease is under control, and tooth #19 is symptom free and shows absence of AP. The endodontists need to be aware of the existence of SS and the possible effects of the use of disease-modifying antirheumatic drugs and biologic medications on the

  13. Implications of pathogenesis by Erwinia amylovora on rosaceous stigmas to biological control of fire blight.

    PubMed

    Johnson, K B; Sawyer, T L; Stockwell, V O; Temple, T N

    2009-02-01

    As a prerequisite to infection of flowers, Erwinia amylovora grows epiphytically on stigmas, which provide a conducive habitat for bacterial growth. Stigmas also support growth of several other bacterial genera, which allows for biological control of fire blight; although, in practice, it is very difficult to exclude E. amylovora completely from this habitat. We investigated the dynamics of growth suppression of E. amylovora by comparing the ability of virulent and avirulent strains of E. amylovora to compete with each other on stigmas of pear, apple, and blackberry, and to compete with a co-inoculated mixture of effective bacterial antagonists. When strains were inoculated individually, virulent E. amylovora strain Ea153N attained the highest population size on stigmas, with population sizes that were approximately double those of an avirulent hrpL mutant of Ea153 or the bacterial antagonists. In competition experiments, growth of the avirulent derivative was suppressed by the antagonist mixture to a greater extent than the virulent strain. Unexpectedly, the virulent strain enhanced the population size of the antagonist mixture. Similarly, a small dose of virulent Ea153N added to inoculum of an avirulent hrpL mutant of Ea153 significantly increased the population size of the avirulent strain. A pathogenesis-gene reporter strain, Ea153 dspE::gfp, was applied to flowers and a subset of the population expressed the green fluorescent protein while growing epiphytically on stigmas of apple. These results are consistent with the hypothesis that virulent E. amylovora modifies the epiphytic habitat presented by the stigma through a pathogenesis-related process, which increases host resources available to itself and, coincidentally, to nonpathogenic competitors. Over nine orchard trials, avirulent Ea153 hrpL significantly suppressed the incidence of fire blight four times compared with six for the antagonist mixture. The degree of biological control achievable with an

  14. The importance of the small RNA chaperone Hfq for growth of epidemic Yersinia pestis, but not Yersinia pseudotuberculosis, with implications for plague biology.

    PubMed

    Bai, Guangchun; Golubov, Andrey; Smith, Eric A; McDonough, Kathleen A

    2010-08-01

    Yersinia pestis, the etiologic agent of plague, has only recently evolved from Yersinia pseudotuberculosis. hfq deletion caused severe growth restriction at 37 degrees C in Y. pestis but not in Y. pseudotuberculosis. Strains from all epidemic plague biovars were similarly affected, implicating Hfq, and likely small RNAs (sRNAs), in the unique biology of the plague bacillus.

  15. An Advanced Organometallic Lab Experiment with Biological Implications: Synthesis and Characterization of Fe[subscript 2](µ-S[subscript 2])(C0)[subscript 6

    ERIC Educational Resources Information Center

    Barrett, Jacob; Spentzos, Ariana; Works, Carmen

    2015-01-01

    The organometallic complex Fe[subscript 2](µ-S[subscript 2])(CO)[subscript 6] has interesting biological implications. The concepts of bio-organometallic chemistry are rarely discussed at the undergraduate level, but this experiment can start such a conversation and, in addition, teach valuable synthetic techniques. The lab experiment takes a…

  16. An Advanced Organometallic Lab Experiment with Biological Implications: Synthesis and Characterization of Fe[subscript 2](µ-S[subscript 2])(C0)[subscript 6

    ERIC Educational Resources Information Center

    Barrett, Jacob; Spentzos, Ariana; Works, Carmen

    2015-01-01

    The organometallic complex Fe[subscript 2](µ-S[subscript 2])(CO)[subscript 6] has interesting biological implications. The concepts of bio-organometallic chemistry are rarely discussed at the undergraduate level, but this experiment can start such a conversation and, in addition, teach valuable synthetic techniques. The lab experiment takes a…

  17. Eco-evolutionary responses of Bromus tectorum to climate change: implications for biological invasions.

    PubMed

    Zelikova, Tamara J; Hufbauer, Ruth A; Reed, Sasha C; Wertin, Timothy; Fettig, Christa; Belnap, Jayne

    2013-05-01

    implications for B. tectorum invasion dynamics on the Colorado Plateau.

  18. Predicting potential global distributions of two Miscanthus grasses: implications for horticulture, biofuel production, and biological invasions.

    PubMed

    Hager, Heather A; Sinasac, Sarah E; Gedalof, Ze'ev; Newman, Jonathan A

    2014-01-01

    In many regions, large proportions of the naturalized and invasive non-native floras were originally introduced deliberately by humans. Pest risk assessments are now used in many jurisdictions to regulate the importation of species and usually include an estimation of the potential distribution in the import area. Two species of Asian grass (Miscanthus sacchariflorus and M. sinensis) that were originally introduced to North America as ornamental plants have since escaped cultivation. These species and their hybrid offspring are now receiving attention for large-scale production as biofuel crops in North America and elsewhere. We evaluated their potential global climate suitability for cultivation and potential invasion using the niche model CLIMEX and evaluated the models' sensitivity to the parameter values. We then compared the sensitivity of projections of future climatically suitable area under two climate models and two emissions scenarios. The models indicate that the species have been introduced to most of the potential global climatically suitable areas in the northern but not the southern hemisphere. The more narrowly distributed species (M. sacchariflorus) is more sensitive to changes in model parameters, which could have implications for modelling species of conservation concern. Climate projections indicate likely contractions in potential range in the south, but expansions in the north, particularly in introduced areas where biomass production trials are under way. Climate sensitivity analysis shows that projections differ more between the selected climate change models than between the selected emissions scenarios. Local-scale assessments are required to overlay suitable habitat with climate projections to estimate areas of cultivation potential and invasion risk.

  19. Predicting Potential Global Distributions of Two Miscanthus Grasses: Implications for Horticulture, Biofuel Production, and Biological Invasions

    PubMed Central

    Hager, Heather A.; Sinasac, Sarah E.; Gedalof, Ze’ev; Newman, Jonathan A.

    2014-01-01

    In many regions, large proportions of the naturalized and invasive non-native floras were originally introduced deliberately by humans. Pest risk assessments are now used in many jurisdictions to regulate the importation of species and usually include an estimation of the potential distribution in the import area. Two species of Asian grass (Miscanthus sacchariflorus and M. sinensis) that were originally introduced to North America as ornamental plants have since escaped cultivation. These species and their hybrid offspring are now receiving attention for large-scale production as biofuel crops in North America and elsewhere. We evaluated their potential global climate suitability for cultivation and potential invasion using the niche model CLIMEX and evaluated the models’ sensitivity to the parameter values. We then compared the sensitivity of projections of future climatically suitable area under two climate models and two emissions scenarios. The models indicate that the species have been introduced to most of the potential global climatically suitable areas in the northern but not the southern hemisphere. The more narrowly distributed species (M. sacchariflorus) is more sensitive to changes in model parameters, which could have implications for modelling species of conservation concern. Climate projections indicate likely contractions in potential range in the south, but expansions in the north, particularly in introduced areas where biomass production trials are under way. Climate sensitivity analysis shows that projections differ more between the selected climate change models than between the selected emissions scenarios. Local-scale assessments are required to overlay suitable habitat with climate projections to estimate areas of cultivation potential and invasion risk. PMID:24945154

  20. Eco-evolutionary responses of Bromus tectorum to climate change: implications for biological invasions

    PubMed Central

    Zelikova, Tamara J; Hufbauer, Ruth A; Reed, Sasha C; Wertin, Timothy; Fettig, Christa; Belnap, Jayne

    2013-01-01

    implications for B. tectorum invasion dynamics on the Colorado Plateau. PMID:23762522

  1. Cell and molecular biology of simian virus 40: implications for human infections and disease

    NASA Technical Reports Server (NTRS)

    Butel, J. S.; Lednicky, J. A.

    1999-01-01

    Simian virus 40 (SV40), a polyomavirus of rhesus macaque origin, was discovered in 1960 as a contaminant of polio vaccines that were distributed to millions of people from 1955 through early 1963. SV40 is a potent DNA tumor virus that induces tumors in rodents and transforms many types of cells in culture, including those of human origin. This virus has been a favored laboratory model for mechanistic studies of molecular processes in eukaryotic cells and of cellular transformation. The viral replication protein, named large T antigen (T-ag), is also the viral oncoprotein. There is a single serotype of SV40, but multiple strains of virus exist that are distinguishable by nucleotide differences in the regulatory region of the viral genome and in the part of the T-ag gene that encodes the protein's carboxyl terminus. Natural infections in monkeys by SV40 are usually benign but may become pathogenic in immunocompromised animals, and multiple tissues can be infected. SV40 can replicate in certain types of simian and human cells. SV40-neutralizing antibodies have been detected in individuals not exposed to contaminated polio vaccines. SV40 DNA has been identified in some normal human tissues, and there are accumulating reports of detection of SV40 DNA and/or T-ag in a variety of human tumors. This review presents aspects of replication and cell transformation by SV40 and considers their implications for human infections and disease pathogenesis by the virus. Critical assessment of virologic and epidemiologic data suggests a probable causative role for SV40 in certain human cancers, but additional studies are necessary to prove etiology.

  2. Eco-evolutionary responses of Bromus tectorum to climate change: implications for biological invasions

    USGS Publications Warehouse

    Zelikova, Tamara J.; Hufbauer, Ruth A.; Reed, Sasha C.; Wertin, Timothy M.; Fettig, Christa; Belnap, Jayne

    2013-01-01

    implications for B. tectorum invasion dynamics on the Colorado Plateau.

  3. Cell and molecular biology of simian virus 40: implications for human infections and disease

    NASA Technical Reports Server (NTRS)

    Butel, J. S.; Lednicky, J. A.

    1999-01-01

    Simian virus 40 (SV40), a polyomavirus of rhesus macaque origin, was discovered in 1960 as a contaminant of polio vaccines that were distributed to millions of people from 1955 through early 1963. SV40 is a potent DNA tumor virus that induces tumors in rodents and transforms many types of cells in culture, including those of human origin. This virus has been a favored laboratory model for mechanistic studies of molecular processes in eukaryotic cells and of cellular transformation. The viral replication protein, named large T antigen (T-ag), is also the viral oncoprotein. There is a single serotype of SV40, but multiple strains of virus exist that are distinguishable by nucleotide differences in the regulatory region of the viral genome and in the part of the T-ag gene that encodes the protein's carboxyl terminus. Natural infections in monkeys by SV40 are usually benign but may become pathogenic in immunocompromised animals, and multiple tissues can be infected. SV40 can replicate in certain types of simian and human cells. SV40-neutralizing antibodies have been detected in individuals not exposed to contaminated polio vaccines. SV40 DNA has been identified in some normal human tissues, and there are accumulating reports of detection of SV40 DNA and/or T-ag in a variety of human tumors. This review presents aspects of replication and cell transformation by SV40 and considers their implications for human infections and disease pathogenesis by the virus. Critical assessment of virologic and epidemiologic data suggests a probable causative role for SV40 in certain human cancers, but additional studies are necessary to prove etiology.

  4. Degradation of biological weapons agents in the environment: implications for terrorism response.

    PubMed

    Stuart, Amy L; Wilkening, Dean A

    2005-04-15

    We investigate the impact on effective terrorism response of the viability degradation of biological weapons agents in the environment. We briefly review the scientific understanding and modeling of agent environmental viability degradation. In general, agent susceptibility to viability loss is greatest for vegetative bacteria, intermediate for viruses, and least for bacterial spores. Survival is greatest in soil and progressively decreases in the following environments: textiles, water, hard surfaces, and air. There is little detailed understanding of loss mechanisms. We analyze the time behavior and sensitivity of four mathematical models that are used to represent environmental viability degradation (the exponential, probability, and first- and second-order catastrophic decay models). The models behave similarly at short times (<30 min for our example case) but diverge to significantly different values at intermediate to long times. Hence, for a release event in which the majority of atmospheric exposure or deposition occurs oververy short times, the current response models likely provide a good representation of the hazard. For longer time phenomena, including decontamination, the current model capabilities are likely insufficient. Finally, we implement each model in a simple numerical integration of anthrax dispersion, viability degradation, and dose response. Decay models spanning the current knowledge of airborne degradation result in vastly different predicted hazard areas. This confounds attempts to determine necessary medical and decontamination measures. Hence,the current level of understanding and representation of environmental viability degradation in response models is inadequate to inform appropriate emergency response measures.

  5. In Situ Biological Contamination Studies of the Moon: Implications for Planetary Protection and Life Detection Missions

    NASA Technical Reports Server (NTRS)

    Glavin, Daniel P.; Dworkin, Jason P.; Lupisella, Mark; Williams, David R.; Kminek, Gerhard; Rummel, John D.

    2010-01-01

    NASA and ESA have outlined visions for solar system exploration that will include a series of lunar robotic precursor missions to prepare for, and support a human return to the Moan, and future human exploration of Mars and other destinations, including possibly asteroids. One of the guiding principles for exploration is to pursue compelling scientific questions about the origin and evolution of life. The search for life on objects such as Mars will require careful operations, and that all systems be sufficiently cleaned and sterilized prior to launch to ensure that the scientific integrity of extraterrestrial samples is not jeopardized by terrestrial organic contamination. Under the Committee on Space Research's (COSPAR's) current planetary protection policy for the Moon, no sterilization procedures are required for outbound lunar spacecraft, nor is there a different planetary protection category for human missions, although preliminary C SPAR policy guidelines for human missions to Mars have been developed. Future in situ investigations of a variety of locations on the Moon by highly sensitive instruments designed to search for biologically derived organic compounds would help assess the contamination of the Moon by lunar spacecraft. These studies could also provide valuable "ground truth" data for Mars sample return missions and help define planetary protection requirements for future Mars bound spacecraft carrying life detection experiments. In addition, studies of the impact of terrestrial contamination of the lunar surface by the Apollo astronauts could provide valuable data to help refine future: Mars surface exploration plans for a human mission to Mars.

  6. Evolution of aphidophagous ladybird populations in a vegetable crop and implications as biological agents.

    PubMed

    Francis, F; Colignon, P; Hastir, P; Haubruge, E; Gaspar, C

    2001-01-01

    Aphidophagous predators such as hoverfly and ladybird beetles are effective biological agents to control aphid pests in perennial and annual cultivated species. Introduction and conservation of beneficial insects are two ways to increase natural control of pests. Whether massive releases of entomophagous insects are expensive and time consuming, the preservation of predator natural populations can be expected by reducing and by adapting chemical treatments in crop fields. Vegetable cultivated areas increased in Belgium for several years, mainly Fabaceae species such as peas and beans. In this work, the evolution of ladybird species population was assessed from May to June in broad bean fields (Vicia faba L.) between Waremme and Hannut, in Hesbaye. Weekly, the aphid and aphidophagous beetle populations were collected from yellow traps and determined on plants by visual observations. Even if five ladybird species were identified, three of them represented more than 95% of the collected insects (Coccinella septempunctata L., Propylea quatuor-decimpunctata L. and Psyllobora vingintiduopunctata L.). Evolution of coccinellid populations during the cultivation season was discussed in relation to the presence of potential aphid preys and the agrochemical treatments which were applied. Integrated pest management in vegetable fields constitute a reliable way to increase the quality level of fresh vegetables in terms of pesticide residue limitations.

  7. The tertiary structure of group II introns: implications for biological function and evolution

    PubMed Central

    Pyle, Anna Marie

    2015-01-01

    Group II introns are some of the largest ribozymes in nature, and they are a major source of information about RNA assembly and tertiary structural organization. These introns are of biological significance because they are self-splicing mobile elements that have migrated into diverse genomes and played a major role in the genomic organization and metabolism of most life forms. The tertiary structure of group II introns has been the subject of many phylogenetic, genetic, biochemical and biophysical investigations, all of which are consistent with the recent crystal structure of an intact group IIC intron from the alkaliphilic eubacterium Oceanobacillus iheyensis. The crystal structure reveals that catalytic intron domain V is enfolded within the other intronic domains through an elaborate network of diverse tertiary interactions. Within the folded core, DV adopts an activated conformation that readily binds catalytic metal ions and positions them in a manner appropriate for reaction with nucleic acid targets. The tertiary structure of the group II intron reveals new information on motifs for RNA architectural organization, mechanisms of group II intron catalysis, and the evolutionary relationships among RNA processing systems. Guided by the structure and the wealth of previous genetic and biochemical work, it is now possible to deduce the probable location of DVI and the site of additional domains that contribute to the function of the highly derived group IIB and IIA introns. PMID:20446804

  8. Insertion sequences shared by Bordetella species and implications for the biological diagnosis of pertussis syndrome.

    PubMed

    Tizolova, A; Guiso, N; Guillot, S

    2013-01-01

    The molecular diagnosis of pertussis and parapertussis syndromes is based on the detection of insertion sequences (IS) 481 and 1001, respectively. However, these IS are also detected in the genomes of various Bordetella species, such that they are not specific for either B. pertussis or B. parapertussis. Therefore, we screened the genome of recently circulating isolates of Bordetella species to compare the prevalence of IS481, IS1001 and, also IS1002 with previously published data and to sequence all IS detected. We also investigated whether the numbers of IS481 and IS1001 copies vary in recently circulating isolates of the different Bordetella species. We used the polymerase chain reaction (PCR) method for screening the genome of circulating isolates and to prepare the fragments for sequencing. We used Southern blotting and quantitative real-time PCR for quantification of the numbers of IS. We found no significant diversity in the sequences of the IS harboured in the genomes of the Bordetella isolates screened, except for a 71-nucleotide deletion from IS1002 in B. bronchiseptica. The IS copy numbers in the genome of recently circulating isolates were similar to those in reference strains. Our results confirm that biological diagnosis targeting the IS481 and IS1001 elements are not specific and detect the species B. pertussis, B. holmesii and B. bronchiseptica (IS481), and B. parapertussis and B. bronchiseptica (IS1001).

  9. Germination biology of Hibiscus tridactylites in Australia and the implications for weed management

    PubMed Central

    Chauhan, Bhagirath Singh

    2016-01-01

    Hibiscus tridactylites is a problematic broadleaf weed in many crops in Australia; however, very limited information is available on seed germination biology of Australian populations. Experiments were conducted to evaluate the effect of environmental factors on germination and emergence of H. tridactylites. Germination was stimulated by seed scarification, suggesting the inhibition of germination in this species is mainly due to the hard seed coat. Germination was not affected by light conditions, suggesting that seeds of this species are not photoblastic. Germination was higher at alternating day/night temperatures of 30/20 °C (74%) and 35/25 °C (69%) than at 25/15 °C (63%). Moderate salinity and water stress did not inhibit germination of H. tridactylites. Seedling emergence of H. tridactylites was highest (57%) for the seeds buried at a 2 cm depth in the soil; 18% of seedlings emerged from seeds buried at 8 cm but no seedlings emerged below this depth. Soil inversion by tillage to bury weed seeds below their maximum depth of emergence could serve an important tool for managing H. tridactylites. PMID:27174752

  10. Germination biology of Hibiscus tridactylites in Australia and the implications for weed management.

    PubMed

    Chauhan, Bhagirath Singh

    2016-05-13

    Hibiscus tridactylites is a problematic broadleaf weed in many crops in Australia; however, very limited information is available on seed germination biology of Australian populations. Experiments were conducted to evaluate the effect of environmental factors on germination and emergence of H. tridactylites. Germination was stimulated by seed scarification, suggesting the inhibition of germination in this species is mainly due to the hard seed coat. Germination was not affected by light conditions, suggesting that seeds of this species are not photoblastic. Germination was higher at alternating day/night temperatures of 30/20 °C (74%) and 35/25 °C (69%) than at 25/15 °C (63%). Moderate salinity and water stress did not inhibit germination of H. tridactylites. Seedling emergence of H. tridactylites was highest (57%) for the seeds buried at a 2 cm depth in the soil; 18% of seedlings emerged from seeds buried at 8 cm but no seedlings emerged below this depth. Soil inversion by tillage to bury weed seeds below their maximum depth of emergence could serve an important tool for managing H. tridactylites.

  11. Influence of membrane lipid composition on flavonoid-membrane interactions: Implications on their biological activity.

    PubMed

    Selvaraj, Stalin; Krishnaswamy, Sridharan; Devashya, Venkappayya; Sethuraman, Swaminathan; Krishnan, Uma Maheswari

    2015-04-01

    The membrane interactions and localization of flavonoids play a vital role in altering membrane-mediated cell signaling cascades as well as influence the pharmacological activities such as anti-tumour, anti-microbial and anti-oxidant properties of flavonoids. Various techniques have been used to investigate the membrane interaction of flavonoids. These include partition coefficient, fluorescence anisotropy, differential scanning calorimetry, NMR spectroscopy, electrophysiological methods and molecular dynamics simulations. Each technique will provide specific information about either alteration of membrane fluidity or localization of flavonoids within the lipid bilayer. Apart from the diverse techniques employed, the concentrations of flavonoids and lipid membrane composition employed in various studies reported in literature also are different and together these variables contribute to diverse findings that sometimes contradict each other. This review highlights different techniques employed to investigate the membrane interaction of flavonoids with special emphasis on erythrocyte model membrane systems and their significance in understanding the nature and extent of flavonoid-membrane interactions. We also attempt to correlate the membrane localization and alteration in membrane fluidity with the biological activities of flavonoids such as anti-oxidant, anti-cancer and anti-microbial properties.

  12. Learning to see again: biological constraints on cortical plasticity and the implications for sight restoration technologies

    NASA Astrophysics Data System (ADS)

    Beyeler, Michael; Rokem, Ariel; Boynton, Geoffrey M.; Fine, Ione

    2017-10-01

    The ‘bionic eye’—so long a dream of the future—is finally becoming a reality with retinal prostheses available to patients in both the US and Europe. However, clinical experience with these implants has made it apparent that the visual information provided by these devices differs substantially from normal sight. Consequently, the ability of patients to learn to make use of this abnormal retinal input plays a critical role in whether or not some functional vision is successfully regained. The goal of the present review is to summarize the vast basic science literature on developmental and adult cortical plasticity with an emphasis on how this literature might relate to the field of prosthetic vision. We begin with describing the distortion and information loss likely to be experienced by visual prosthesis users. We then define cortical plasticity and perceptual learning, and describe what is known, and what is unknown, about visual plasticity across the hierarchy of brain regions involved in visual processing, and across different stages of life. We close by discussing what is known about brain plasticity in sight restoration patients and discuss biological mechanisms that might eventually be harnessed to improve visual learning in these patients.

  13. Modeling of intraluminal heating of biological tissue: implications for treatment of benign prostatic hyperplasia.

    PubMed

    Anvari, B; Rastegar, S; Motamedi, M

    1994-09-01

    A computer model for predicting the thermal response of a biological tissue to different intraluminal heating modalities is presented. A practical application of the model is to calculate the temperature distributions during thermal coagulation of prostate by contact heating and radiative heating. The model uses a two-dimensional axisymmetric diffusion approximation method to calculate the light distribution during radiative heating. The traditional Pennes' bio-heat equation is used to calculate the temperatures in the presence of blood flow. An implicit finite difference scheme with nonuniform grid spacings is used to solve the diffusion equation for light distribution and the bio-heat equation. Model results indicate that the radiative heating of prostate by Nd:YAG (1064 mm) and diode (810 mm) lasers can be a more effective and efficient means of coagulating a large volume of prostate, as compared to contact heating of the tissue. Blood perfusion is shown to provide a considerable heat sink as the laser exposure time is increased. Surface cooling by irrigation during the laser irradiation of tissue is shown to be an effective method for delaying tissue explosion and obtaining a large volume of coagulated tissue. The model also shows that the volume of the coagulated tissue is appreciably altered by a change in the rate of energy deposition.

  14. HNS(+) and HSN(+) cations: Electronic states, spin-rovibronic spectroscopy with planetary and biological implications.

    PubMed

    Trabelsi, Tarek; Ben Yaghlane, Saida; Al Mogren, Muneerah Mogren; Francisco, Joseph S; Hochlaf, Majdi

    2016-08-28

    Ab initio methods in conjunction with a large basis set are used to compute the potential energy surfaces of the 12 lowest electronic states of the HNS(+) and HSN(+) isomeric forms. These potentials are used in discussions of the metastability of these cations and plausible mechanisms for the H(+)/H + SN(+)/SN, S/S(+) + NH(+)/NH, N/N(+) + SH(+)/SH ion-molecule reactions. Interestingly, the low rovibrational levels of HSN(+)(1(2)A″) and HNS(+)(1(2)A″) electronically excited ions are predicted to be long-lived. Both ions are suggested to be a suitable candidate for light-sensitive NO(⋅) donor in vivo and as a possible marker for the detection of intermediates in nitrites + H2S reactions at the cellular level. The full spin rovibronic levels of HNS(+) are presented, which may assist in the experimental identification of HNS(+) and HSN(+) ions and in elucidating their roles in astrophysical and biological media.

  15. Genetic Profiling of Cancers of the Digestive System: Biological Insights and Clinical Implications.

    PubMed

    Stenzinger, Albrecht; Weichert, Wilko

    2017-02-09

    Massive parallel sequencing technologies (next-generation sequencing) have enabled us to draw a comprehensive landscape of the genomic aberrations underlying common cancers of the digestive system, and they have thus revolutionized our understanding of the genomic makeup and biology of these tumors. Apart from the commonly mutated founder genes, e.g., KRAS and TP53, we now have detailed information on additional and less frequent genomic events for every major digestive system cancer. However, many challenging issues remain when it comes to translating these findings into clinical applications. Recent examples are the precise definition of the role of genomic heterogeneity and tumor evolution in metastatic spread and their impact on oncologic therapy. Other unresolved issues include the usefulness of identified drivers as novel drug targets and predictive biomarkers, as well as the development of strategies to implement broad genomic testing in individualized patient care. This review aims to dissect and discuss these topics for selected major cancers. © 2017 S. Karger AG, Basel.

  16. Toward the laboratory identification of [O,N,S,S] isomers: Implications for biological NO chemistry

    NASA Astrophysics Data System (ADS)

    Ayari, Tarek; Jaidane, Nejm-Eddine; Al Mogren, Muneerah Mogren; Francisco, Joseph S.; Hochlaf, Majdi

    2016-06-01

    Benchmark ab initio calculations are performed to investigate the stable isomers of [O,N,S,S]. These computations are carried out using coupled cluster (RCCSD(T)) and explicitly correlated coupled cluster methods (RCCSD(T)-F12). In addition to the already known cis isomer of SSNO, nine other stable forms are predicted. The most stable isomer is cis-OSNS. Nine structures are chain bent-bent with relatively large dipole moments which make them detectable, as cis-SSNO, by infrared, far-infrared, and microwave spectroscopies. We found also a C2v isomer (NS2O). Since these species are strongly suggested to play an important role as intermediates during the bioactive reaction products of the NO/H2S interaction, the rotational and vibrational spectroscopic parameters are presented to help aid the in vivo identification and assignment of these spectra. Results from this work show that [O,N,S,S] may play key roles during nitric oxide transport and deliver in biological media, as well as, provide an explanation for the weak characteristic of disulfide bridges within proteins.

  17. In Situ Biological Contamination Studies of the Moon: Implications for Planetary Protection and Life Detection Missions

    NASA Astrophysics Data System (ADS)

    Glavin, Daniel P.; Dworkin, Jason P.; Lupisella, Mark; Williams, David R.; Kminek, Gerhard; Rummel, John D.

    2010-12-01

    NASA and ESA have outlined visions for solar system exploration that will include a series of lunar robotic precursor missions to prepare for, and support a human return to the Moon, and future human exploration of Mars and other destinations, including possibly asteroids. One of the guiding principles for exploration is to pursue compelling scientific questions about the origin and evolution of life. The search for life on objects such as Mars will require careful operations, and that all systems be sufficiently cleaned and sterilized prior to launch to ensure that the scientific integrity of extraterrestrial samples is not jeopardized by terrestrial organic contamination. Under the Committee on Space Research's (COSPAR's) current planetary protection policy for the Moon, no sterilization procedures are required for outbound lunar spacecraft, nor is there a different planetary protection category for human missions, although preliminary COSPAR policy guidelines for human missions to Mars have been developed. Future in situ investigations of a variety of locations on the Moon by highly sensitive instruments designed to search for biologically derived organic compounds would help assess the contamination of the Moon by lunar spacecraft. These studies could also provide valuable "ground truth" data for Mars sample return missions and help define planetary protection requirements for future Mars bound spacecraft carrying life detection experiments. In addition, studies of the impact of terrestrial contamination of the lunar surface by the Apollo astronauts could provide valuable data to help refine future Mars surface exploration plans for a human mission to Mars.

  18. Lone-pair-π interactions: analysis of the physical origin and biological implications.

    PubMed

    Novotný, Jan; Bazzi, Sophia; Marek, Radek; Kozelka, Jiří

    2016-07-28

    Lone-pair-π (lp-π) interactions have been suggested to stabilize DNA and protein structures, and to participate in the formation of DNA-protein complexes. To elucidate their physical origin, we have carried out a theoretical multi-approach analysis of two biologically relevant model systems, water-indole and water-uracil complexes, which we compared with the structurally similar chloride-tetracyanobenzene (TCB) complex previously shown to contain a strong charge-transfer (CT) binding component. We demonstrate that the CT component in lp-π interactions between water and indole/uracil is significantly smaller than that stabilizing the Cl(-)-TCB reference system. The strong lp(Cl(-))-π(TCB) orbital interaction is characterized by a small energy gap and an efficient lp-π* overlap. In contrast, in lp-π interactions between water and indole or uracil, the corresponding energy gap is larger and the overlap less efficient. As a result, water-uracil and water-indole interactions are weak forces composed by smaller contributions from all energy components: electrostatics, polarization, dispersion, and charge transfer. In addition, indole exhibits a negative electrostatic potential at its π-face, making lp-π interactions less favorable than O-Hπ hydrogen bonding. Consequently, some of the water-tryptophan contacts observed in X-ray structures of proteins and previously interpreted as lp-π interactions [Luisi, et al., Proteins, 2004, 57, 1-8], might in fact arise from O-Hπ hydrogen bonding.

  19. Learning to see again: biological constraints on cortical plasticity and the implications for sight restoration technologies.

    PubMed

    Beyeler, Michael; Rokem, Ariel; Boynton, Geoffrey M; Fine, Ione

    2017-10-01

    The 'bionic eye'-so long a dream of the future-is finally becoming a reality with retinal prostheses available to patients in both the US and Europe. However, clinical experience with these implants has made it apparent that the visual information provided by these devices differs substantially from normal sight. Consequently, the ability of patients to learn to make use of this abnormal retinal input plays a critical role in whether or not some functional vision is successfully regained. The goal of the present review is to summarize the vast basic science literature on developmental and adult cortical plasticity with an emphasis on how this literature might relate to the field of prosthetic vision. We begin with describing the distortion and information loss likely to be experienced by visual prosthesis users. We then define cortical plasticity and perceptual learning, and describe what is known, and what is unknown, about visual plasticity across the hierarchy of brain regions involved in visual processing, and across different stages of life. We close by discussing what is known about brain plasticity in sight restoration patients and discuss biological mechanisms that might eventually be harnessed to improve visual learning in these patients.

  20. Germination biology of Hibiscus tridactylites in Australia and the implications for weed management

    NASA Astrophysics Data System (ADS)

    Chauhan, Bhagirath Singh

    2016-05-01

    Hibiscus tridactylites is a problematic broadleaf weed in many crops in Australia; however, very limited information is available on seed germination biology of Australian populations. Experiments were conducted to evaluate the effect of environmental factors on germination and emergence of H. tridactylites. Germination was stimulated by seed scarification, suggesting the inhibition of germination in this species is mainly due to the hard seed coat. Germination was not affected by light conditions, suggesting that seeds of this species are not photoblastic. Germination was higher at alternating day/night temperatures of 30/20 °C (74%) and 35/25 °C (69%) than at 25/15 °C (63%). Moderate salinity and water stress did not inhibit germination of H. tridactylites. Seedling emergence of H. tridactylites was highest (57%) for the seeds buried at a 2 cm depth in the soil; 18% of seedlings emerged from seeds buried at 8 cm but no seedlings emerged below this depth. Soil inversion by tillage to bury weed seeds below their maximum depth of emergence could serve an important tool for managing H. tridactylites.

  1. Relative humidity patterns and fog water precipitation in the Atacama Desert and biological implications

    NASA Astrophysics Data System (ADS)

    CáCeres, Luis; Gómez-Silva, Benito; Garró, Ximena; RodríGuez, Violeta; Monardes, Vinka; McKay, Christopher P.

    2007-12-01

    Fog is the most important source of water for native plants and biological soil crusts in the Atacama Desert. Since fog depends upon available moisture, an understanding of climatic patterns is essential to interpret its present-day occurrence and distribution. In this work, temperature and humidity of ambient air and collected fog water in selected sites were studied across a transect from the coast to inland of the Atacama Desert, by using automated outdoor sensors for temperature and relative humidity, and also fog collectors equipped with automated rain gauges to measure collected fog water flow rates. Field measurements were organized to determine fog and collected fog water patterns at three selected sites, namely, Coloso, Inacesa and Yungay in addition to the relative humidity and temperature variation with altitude at Coloso Mountain located within Coloso site. The results show a decreasing trend in the collected fog water flow rates from the coast toward inland locations. Daily thermal oscillations at each site are closely related to fog water collection. At Coloso Mountain, an adiabatic cooling-like effect of the wind ascending its slope was observed preferentially during nighttime. At daytime, occasional distortions observed in the temperature profiles are probably produced by a thermal driven-air convection process along the Coloso Mountain slope heated by solar radiation. The reduction in available water from fog from the coast to the inland site is consistent with the reduction in colonization rate for hypolithic cyanobacteria along this same transect.

  2. Reductive assays for S-nitrosothiols: implications for measurements in biological systems.

    PubMed

    Fang, K; Ragsdale, N V; Carey, R M; MacDonald, T; Gaston, B

    1998-11-27

    Bioactive SNOs are found in many tissues. We speculated SNOs might be misidentified in conventional assays which reduce NO-3 to NO. S-Nitrosothiols were exposed to saturated VCl3 in HCl, 1% KI in acetic acid, photolysis, or CuCl and CSH in He; NO was measured by chemiluminescence. S-Nitrosothiols were readily detected in VCl3 but not in KI. Reduction in CuCl/cysteine was linear (r2 = 1.0, n = 6), sensitive to 10 pmol, and eliminated by HgCl2; it did not detect NO-2, NO-3, or 3-nitrotyrosine. S-Nitrosothiols represented approximately 2.9% of NOx assayed by VCl3 in human serum, of which <5% were low-mass species. In summary, (i) conventional assays may misidentify NO-3, but not NO-2, as SNOs; and (ii) chemiluminescence/reduction systems may be sensitive and specific as SNO assays. We suggest that assay of the SNO fraction in biological NOx may be more relevant and feasible than is now appreciated.

  3. A Portrait of the Transcriptome of the Neglected Trematode, Fasciola gigantica—Biological and Biotechnological Implications

    PubMed Central

    Young, Neil D.; Jex, Aaron R.; Cantacessi, Cinzia; Hall, Ross S.; Campbell, Bronwyn E.; Spithill, Terence W.; Tangkawattana, Sirikachorn; Tangkawattana, Prasarn; Laha, Thewarach; Gasser, Robin B.

    2011-01-01

    Fasciola gigantica (Digenea) is an important foodborne trematode that causes liver fluke disease (fascioliasis) in mammals, including ungulates and humans, mainly in tropical climatic zones of the world. Despite its socioeconomic impact, almost nothing is known about the molecular biology of this parasite, its interplay with its hosts, and the pathogenesis of fascioliasis. Modern genomic technologies now provide unique opportunities to rapidly tackle these exciting areas. The present study reports the first transcriptome representing the adult stage of F. gigantica (of bovid origin), defined using a massively parallel sequencing-coupled bioinformatic approach. From >20 million raw sequence reads, >30,000 contiguous sequences were assembled, of which most were novel. Relative levels of transcription were determined for individual molecules, which were also characterized (at the inferred amino acid level) based on homology, gene ontology, and/or pathway mapping. Comparisons of the transcriptome of F. gigantica with those of other trematodes, including F. hepatica, revealed similarities in transcription for molecules inferred to have key roles in parasite-host interactions. Overall, the present dataset should provide a solid foundation for future fundamental genomic, proteomic, and metabolomic explorations of F. gigantica, as well as a basis for applied outcomes such as the development of novel methods of intervention against this neglected parasite. PMID:21408104

  4. Brain Cancer Stem Cells in Adults and Children: Cell Biology and Therapeutic Implications.

    PubMed

    Abou-Antoun, Tamara J; Hale, James S; Lathia, Justin D; Dombrowski, Stephen M

    2017-04-01

    Brain tumors represent some of the most malignant cancers in both children and adults. Current treatment options target the majority of tumor cells but do not adequately target self-renewing cancer stem cells (CSCs). CSCs have been reported to resist the most aggressive radiation and chemotherapies, and give rise to recurrent, treatment-resistant secondary malignancies. With advancing technologies, we now have a better understanding of the genetic, epigenetic and molecular signatures and microenvironmental influences which are useful in distinguishing between distinctly different tumor subtypes. As a result, efforts are now underway to identify and target CSCs within various tumor subtypes based on this foundation. This review discusses progress in CSC biology as it relates to targeted therapies which may be uniquely different between pediatric and adult brain tumors. Studies to date suggest that pediatric brain tumors may benefit more from genetic and epigenetic targeted therapies, while combination treatments aimed specifically at multiple molecular pathways may be more effective in treating adult brain tumors which seem to have a greater propensity towards microenvironmental interactions. Ultimately, CSC targeting approaches in combination with current clinical therapies have the potential to be more effective owing to their ability to compromise CSCs maintenance and the mechanisms which underlie their highly aggressive and deadly nature.

  5. Nanoparticle size and surface properties determine the protein corona with possible implications for biological impacts

    PubMed Central

    Lundqvist, Martin; Stigler, Johannes; Elia, Giuliano; Lynch, Iseult; Cedervall, Tommy; Dawson, Kenneth A.

    2008-01-01

    Nanoparticles in a biological fluid (plasma, or otherwise) associate with a range of biopolymers, especially proteins, organized into the “protein corona” that is associated with the nanoparticle and continuously exchanging with the proteins in the environment. Methodologies to determine the corona and to understand its dependence on nanomaterial properties are likely to become important in bionanoscience. Here, we study the long-lived (“hard”) protein corona formed from human plasma for a range of nanoparticles that differ in surface properties and size. Six different polystyrene nanoparticles were studied: three different surface chemistries (plain PS, carboxyl-modified, and amine-modified) and two sizes of each (50 and 100 nm), enabling us to perform systematic studies of the effect of surface properties and size on the detailed protein coronas. Proteins in the corona that are conserved and unique across the nanoparticle types were identified and classified according to the protein functional properties. Remarkably, both size and surface properties were found to play a very significant role in determining the nanoparticle coronas on the different particles of identical materials. We comment on the future need for scientific understanding, characterization, and possibly some additional emphasis on standards for the surfaces of nanoparticles. PMID:18809927

  6. An analysis of the transcriptome of Teladorsagia circumcincta: its biological and biotechnological implications

    PubMed Central

    2012-01-01

    Background Teladorsagia circumcincta (order Strongylida) is an economically important parasitic nematode of small ruminants (including sheep and goats) in temperate climatic regions of the world. Improved insights into the molecular biology of this parasite could underpin alternative methods required to control this and related parasites, in order to circumvent major problems associated with anthelmintic resistance. The aims of the present study were to define the transcriptome of the adult stage of T. circumcincta and to infer the main pathways linked to molecules known to be expressed in this nematode. Since sheep develop acquired immunity against T. circumcincta, there is some potential for the development of a vaccine against this parasite. Hence, we infer excretory/secretory molecules for T. circumcincta as possible immunogens and vaccine candidates. Results A total of 407,357 ESTs were assembled yielding 39,852 putative gene sequences. Conceptual translation predicted 24,013 proteins, which were then subjected to detailed annotation which included pathway mapping of predicted proteins (including 112 excreted/secreted [ES] and 226 transmembrane peptides), domain analysis and GO annotation was carried out using InterProScan along with BLAST2GO. Further analysis was carried out for secretory signal peptides using SignalP and non-classical sec pathway using SecretomeP tools. For ES proteins, key pathways, including Fc epsilon RI, T cell receptor, and chemokine signalling as well as leukocyte transendothelial migration were inferred to be linked to immune responses, along with other pathways related to neurodegenerative diseases and infectious diseases, which warrant detailed future studies. KAAS could identify new and updated pathways like phagosome and protein processing in endoplasmic reticulum. Domain analysis for the assembled dataset revealed families of serine, cysteine and proteinase inhibitors which might represent targets for parasite intervention. Inter

  7. Unraveling the nanoscale surface properties of chitin synthase mutants of Aspergillus fumigatus and their biological implications.

    PubMed

    Alsteens, David; Aimanianda, Vishukumar; Hegde, Pushpa; Pire, Stéphane; Beau, Rémi; Bayry, Jagadeesh; Latgé, Jean-Paul; Dufrêne, Yves F

    2013-07-16

    Understanding the surface properties of the human opportunistic pathogen Aspergillus fumigatus conidia is essential given the important role they play during the fungal interactions with the human host. Although chitin synthases with myosin motor-like domain (CSM) play a major role in cell wall biosynthesis, the extent to which deletion of the CSM genes alter the surface structural and biophysical-biological properties of conidia is not fully characterized. We used three complementary atomic force microscopy techniques-i.e., structural imaging, chemical force microscopy with hydrophobic tips, and single-molecule force spectroscopy with lectin tips-to gain detailed insights into the nanoscale surface properties (ultrastructure, hydrophobicity) and polysaccharide composition of the wild-type and the chitin synthase mutant (ΔcsmA, ΔcsmB, and ΔcsmA/csmB) conidia of A. fumigatus. Wild-type conidia were covered with a highly hydrophobic layer of rodlet nanostructures. By contrast, the surface of the ΔcsmA mutant was almost completely devoid of rodlets, leading to loss of hydrophobicity and exposure of mannan and chitin polysaccharides. The ΔcsmB and ΔcsmA/csmB mutants showed a different behavior, i.e., the surfaces featured poorly organized rodlet layers, yet with a low hydrophobicity and substantial amounts of exposed mannan and chitin at the surface. As the rodlet layer is important for masking recognition of immunogenic fungal cell wall components by innate immune cells, disappearance of rodlet layers in all three chitin synthase mutant conidia was associated with an activation of human dendritic cells. These nanoscale analyses emphasize the important and distinct roles that the CSMA and CSMB genes play in modulating the surface properties and immune interactions of A. fumigatus and demonstrate the power of atomic force microscopy in fungal genetic studies for assessing the phenotypic characteristics of mutants altered in cell surface organization. Copyright

  8. Unsaturated glycerophospholipids mediate heme crystallization: biological implications for hemozoin formation in the kissing bug Rhodnius prolixus.

    PubMed

    Stiebler, Renata; Majerowicz, David; Knudsen, Jens; Gondim, Katia C; Wright, David W; Egan, Timothy J; Oliveira, Marcus F

    2014-01-01

    Hemozoin (Hz) is a heme crystal produced by some blood-feeding organisms, as an efficient way to detoxify heme derived from hemoglobin digestion. In the triatomine insect Rhodnius prolixus, Hz is essentially produced by midgut extracellular phospholipid membranes known as perimicrovillar membranes (PMVM). Here, we investigated the role of commercial glycerophospholipids containing serine, choline and ethanolamine as headgroups and R. prolixus midgut lipids (RML) in heme crystallization. All commercial unsaturated forms of phospholipids, as well as RML, mediated fast and efficient β-hematin formation by means of two kinetically distinct mechanisms: an early and fast component, followed by a late and slow one. The fastest reactions observed were induced by unsaturated forms of phosphatidylethanolamine (uPE) and phosphatidylcholine (uPC), with half-lives of 0.04 and 0.7 minutes, respectively. β-hematin crystal morphologies were strikingly distinct among groups, with uPE producing homogeneous regular brick-shaped crystals. Interestingly, uPC-mediated reactions resulted in two morphologically distinct crystal populations: one less representative group of regular crystals, resembling those induced by uPE, and the other largely represented by crystals with numerous sharp edges and tapered ends. Heme crystallization reactions induced by RML were efficient, with a heme to β-hematin conversion rate higher than 70%, but clearly slower (t1/2 of 9.9-17.7 minutes) than those induced by uPC and uPE. Interestingly, crystals produced by RML were homogeneous in shape and quite similar to those mediated by uPE. Thus, β-hematin formation can be rapidly and efficiently induced by unsaturated glycerophospholipids, particularly uPE and uPC, and may play a role on biological heme crystallization in R. prolixus midgut.

  9. Urinary creatinine concentrations in the U.S. population: implications for urinary biologic monitoring measurements.

    PubMed

    Barr, Dana B; Wilder, Lynn C; Caudill, Samuel P; Gonzalez, Amanda J; Needham, Lance L; Pirkle, James L

    2005-02-01

    Biologic monitoring (i.e., biomonitoring) is used to assess human exposures to environmental and workplace chemicals. Urinary biomonitoring data typically are adjusted to a constant creatinine concentration to correct for variable dilutions among spot samples. Traditionally, this approach has been used in population groups without much diversity. The inclusion of multiple demographic groups in studies using biomonitoring for exposure assessment has increased the variability in the urinary creatinine levels in these study populations. Our objectives were to document the normal range of urinary creatinine concentrations among various demographic groups, evaluate the impact that variations in creatinine concentrations can have on classifying exposure status of individuals in epidemiologic studies, and recommend an approach using multiple regression to adjust for variations in creatinine in multivariate analyses. We performed a weighted multivariate analysis of urinary creatinine concentrations in 22,245 participants of the Third National Health and Nutrition Examination Survey (1988-1994) and established reference ranges (10th-90th percentiles) for each demographic and age category. Significant predictors of urinary creatinine concentration included age group, sex, race/ethnicity, body mass index, and fat-free mass. Time of day that urine samples were collected made a small but statistically significant difference in creatinine concentrations. For an individual, the creatinine-adjusted concentration of an analyte should be compared with a "reference" range derived from persons in a similar demographic group (e.g., children with children, adults with adults). For multiple regression analysis of population groups, we recommend that the analyte concentration (unadjusted for creatinine) should be included in the analysis with urinary creatinine added as a separate independent variable. This approach allows the urinary analyte concentration to be appropriately adjusted for

  10. Evolutionary, biological origins of morality: implications for research with human embryonic stem cells.

    PubMed

    Baschetti, Riccardo

    2005-06-01

    Medical research with human embryonic stem cells, despite its enormous potential to reduce human suffering, is banned in many countries and heavily restricted in others. "Moral reasons" are invoked to justify bans and restrictions on this promising research. Rather surprisingly, while those moral reasons have been extensively discussed and hotly debated in several papers, not a single article on the moral aspects of that research has attempted to answer this fundamental question: What is morality? Considering that a scientifically objective definition of morality is essential to determine whether those moral reasons are justified or groundless, this article focuses on the evolutionary origins of morality and its biological basis. Morality arose as a selectively advantageous product of evolution and preceded all religions and philosophies by millions of years. For the 99% of humankind's evolution, morality was axiomatically aimed at reducing the sufferings of the social members, because pains and afflictions, as expressions of diseases and impairments, tended to hasten the extinction of the small ancestral groups, which characteristically consisted of a few tens of members. Had the therapeutic use of human embryos been available in remote times, our ancestors would have deemed it unquestionably immoral to save amorphous and microscopic agglomerates of insensitive cells representing neither parental nor social investment, at the expense of the lives of the suffering members of their little communities. Unless we venture the untenable thesis that the unlikelihood of extinction of our immense societies entitles us to overturn the meaning of morality, we cannot but conclude that bans and restrictions on research with human embryonic stem cells are patently immoral.

  11. Reproductive biology of the deep brooding coral Seriatopora hystrix: Implications for shallow reef recovery.

    PubMed

    Prasetia, Rian; Sinniger, Frederic; Hashizume, Kaito; Harii, Saki

    2017-01-01

    Mesophotic coral ecosystems (MCEs, between 30 and 150 m depth) are hypothesized to contribute to the recovery of degraded shallow reefs through sexually produced larvae (referred to as Deep Reef Refuge Hypothesis). In Okinawa, Japan, the brooder coral Seriatopora hystrix was reported to be locally extinct in a shallow reef while it was found abundant at a MCE nearby. In this context, S. hystrix represents a key model to test the Deep Reef Refuge Hypothesis and to understand the potential contribution of mesophotic corals to shallow coral reef recovery. However, the reproductive biology of mesophotic S. hystrix and its potential to recolonize shallow reefs is currently unknown. This study reports for the first time, different temporal scales of reproductive periodicity and larval settlement of S. hystrix from an upper mesophotic reef (40 m depth) in Okinawa. We examined reproductive seasonality, lunar, and circadian periodicity (based on polyp dissection, histology, and ex situ planula release observations) and larval settlement rates in the laboratory. Mesophotic S. hystrix reproduced mainly in July and early August, with a small number of planulae being released at the end of May, June and August. Compared to shallow colonies in the same region, mesophotic S. hystrix has a 4-month shorter reproductive season, similar circadian periodicity, and smaller planula size. In addition, most of the planulae settled rapidly, limiting larval dispersal potential. The shorter reproductive season and smaller planula size may result from limited energy available for reproduction at deeper depths, while the similar circadian periodicity suggests that this reproductive aspect is not affected by environmental conditions differing with depth. Overall, contribution of mesophotic S. hystrix to shallow reef rapid recovery appears limited, although they may recruit to shallow reefs through a multistep process over a few generations or through random extreme mixing such as typhoons.

  12. Purification of retroviral vectors for clinical application: biological implications and technological challenges.

    PubMed

    Rodrigues, Teresa; Carrondo, Manuel J T; Alves, Paula M; Cruz, Pedro E

    2007-01-10

    For centuries mankind led a difficult battle against viruses, the smallest infectious agents at the surface of the earth. Nowadays it is possible to use viruses for our benefit, both at a prophylactic level in the production of vaccines and at a therapeutic level in the promising field of gene therapy. Retroviruses were discovered at the end of the 19th century and constitute one of the most effective entities for gene transfer and insertion into the genome of mammalian cells. This attractive feature has intensified research in retroviral vectors development and production over the past years, mainly due to the expectations raised by the concept of gene therapy. The demand for high quality retroviral vectors that meet standard requisites from the regulatory agencies (FDA and EMEA) is therefore increasing, as the technology has moved into clinical trials. The development of safer producer cell lines that can be used in large-scale production will result in the production of large quantities of retroviral stocks. Cost-efficient and scalable purification processes are essential for production of injectable-grade preparations to achieve final implementation of these vectors as therapeutics. Several preparative purification steps already established for proteins can certainly be applied to retroviral vectors, in particular membrane filtration and chromatographic methods. Nevertheless, the special properties of these complex products require technological improvement of the existing purification steps and/or development of particular purification steps to increase productivity and throughput, while maintaining biological activity of the final product. This review focuses on downstream process development in relation to the retroviral vectors characteristics and quality assessment of retroviral stocks for intended use in gene therapy.

  13. Reproductive biology of the deep brooding coral Seriatopora hystrix: Implications for shallow reef recovery

    PubMed Central

    Prasetia, Rian; Sinniger, Frederic; Hashizume, Kaito; Harii, Saki

    2017-01-01

    Mesophotic coral ecosystems (MCEs, between 30 and 150 m depth) are hypothesized to contribute to the recovery of degraded shallow reefs through sexually produced larvae (referred to as Deep Reef Refuge Hypothesis). In Okinawa, Japan, the brooder coral Seriatopora hystrix was reported to be locally extinct in a shallow reef while it was found abundant at a MCE nearby. In this context, S. hystrix represents a key model to test the Deep Reef Refuge Hypothesis and to understand the potential contribution of mesophotic corals to shallow coral reef recovery. However, the reproductive biology of mesophotic S. hystrix and its potential to recolonize shallow reefs is currently unknown. This study reports for the first time, different temporal scales of reproductive periodicity and larval settlement of S. hystrix from an upper mesophotic reef (40 m depth) in Okinawa. We examined reproductive seasonality, lunar, and circadian periodicity (based on polyp dissection, histology, and ex situ planula release observations) and larval settlement rates in the laboratory. Mesophotic S. hystrix reproduced mainly in July and early August, with a small number of planulae being released at the end of May, June and August. Compared to shallow colonies in the same region, mesophotic S. hystrix has a 4-month shorter reproductive season, similar circadian periodicity, and smaller planula size. In addition, most of the planulae settled rapidly, limiting larval dispersal potential. The shorter reproductive season and smaller planula size may result from limited energy available for reproduction at deeper depths, while the similar circadian periodicity suggests that this reproductive aspect is not affected by environmental conditions differing with depth. Overall, contribution of mesophotic S. hystrix to shallow reef rapid recovery appears limited, although they may recruit to shallow reefs through a multistep process over a few generations or through random extreme mixing such as typhoons. PMID

  14. Senemorphism: a novel perspective on aging patterns and its implication for diet-related biology.

    PubMed

    Trindade, Lucas Siqueira; Balduino, Alex; Aigaki, Toshiro; Heddle, Jonathan G

    2012-08-01

    Aging can be described as the accumulation of changes in organisms over time. Aging in organisms undergoing caloric restriction (CR) is widely considered as a slowed version of aging under ad libitum (AL) conditions. However, here we argue that aging under optimized CR is fundamentally different from aging under AL based on the following facts: (1) Comparing the two dietary groups, several age-related changes run in the opposite direction over time; (2) Switching from an AL to a CR diet clearly reverts (not only delays) several "normal" accumulated changes; (3) major causes of death are as different between both groups as they are between species. These observations support the idea that CR and AL initially modulate different metabolic and physiological programs, which exclusively over time generate two biologically different organisms. Such distinct diet-related senescence is analogous to the divergent aging processes and causes of death observed between castes of social insects, such as queens versus workers ("caste-related-senescence") and also between breeding versus non-breeding semelparous animals ("reproduction-related-senescence"). All these aging phenotypes are different not because they accumulate changes at a different rate, but because they accumulate different changes over time. Thus, the environment does not simply affect the individual aging rate through stochastic effects (e.g. U.V.) but also modulates the activation of a particular program/strategy that influences lifespan (e.g. caste, calorie intake). We refer to the environment-dependent aging patterns encoded by the genome as "senemorphism". Based on this idea we propose experimental schemes for aging, evolution and biomedical research.

  15. Ontogeny of taste preferences: basic biology and implications for health12345

    PubMed Central

    Mennella, Julie A

    2014-01-01

    Health initiatives address childhood obesity in part by encouraging good nutrition early in life. This review highlights the science that shows that children naturally prefer higher levels of sweet and salty tastes and reject lower levels of bitter tastes than do adults. Thus, their basic biology does not predispose them to favor the recommended low-sugar, low-sodium, vegetable-rich diets and makes them especially vulnerable to our current food environment of foods high in salt and refined sugars. The good news is that sensory experiences, beginning early in life, can shape preferences. Mothers who consume diets rich in healthy foods can get children off to a good start because flavors are transmitted from the maternal diet to amniotic fluid and mother's milk, and breastfed infants are more accepting of these flavors. In contrast, infants fed formula learn to prefer its unique flavor profile and may have more difficulty initially accepting flavors not found in formula, such as those of fruit and vegetables. Regardless of early feeding mode, infants can learn through repeated exposure and dietary variety if caregivers focus on the child's willingness to consume a food and not just the facial expressions made during feeding. In addition, providing complementary foods low in salt and sugars may help protect the developing child from excess intake later in life. Early-life experiences with healthy tastes and flavors may go a long way toward promoting healthy eating, which could have a significant impact in addressing the many chronic illnesses associated with poor food choice. PMID:24452237

  16. Deletions of CDKN2C in Multiple Myeloma: Biological and Clinical Implications

    PubMed Central

    Leone, Paola E.; Walker, Brian A.; Jenner, Matthew W.; Chiecchio, Laura; Dagrada, GianPaolo; Protheroe, Rebecca K.M.; Johnson, David C.; Dickens, Nicholas J.; Brito, Jose Luis; Else, Monica; Gonzalez, David; Ross, Fiona M.; Chen-Kiang, Selina; Davies, Faith E.; Morgan, Gareth J.

    2008-01-01

    Purpose: Deletions of chromosome 1 have been described in 7-40% of cases of myeloma with inconsistent clinical consequences. CDKN2C at 1p32.3 has been identified in myeloma cell lines as the potential target of the deletion. We tested the clinical impact of 1p deletion and used high resolution techniques to define to role of CDKN2C in primary patient material. Experimental Design: We analyzed 515 cases of monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM) and newly diagnosed multiple myeloma (MM) using fluorescence in situ hybridization (FISH) for deletions of CDNK2C. In 78 myeloma cases, we carried out Affymetrix SNP mapping and U133 plus 2.0 expression arrays. In addition, we performed mutation, methylation and western blotting analysis. Results: By FISH we identified deletion of 1p32.3 (CDKN2C) in 3/66 MGUS (4.5%), 4/39 SMM (10.3%) and 55/369 MM cases (15%). We examined the impact of copy number change at CDKN2C on overall survival (OS), and found that the cases with either hemizygous or homozygous deletion of CDKN2C had a worse OS compared to cases which were intact at this region (22 months vs. 38 months; P = 0.003). Using gene mapping we identified three homozygous deletions (HD) at 1p32.3, containing CDKN2C, all of which lacked expression of CDKN2C. Cases with HD of CDKN2C were the most proliferative myelomas, defined by an expression-based proliferation index, consistent with its biological function as a cyclin-dependent kinase inhibitor. Conclusions: Our results suggest that deletions of CDKN2C are important in the progression and clinical outcome of myeloma. PMID:18829482

  17. Unsaturated Glycerophospholipids Mediate Heme Crystallization: Biological Implications for Hemozoin Formation in the Kissing Bug Rhodnius prolixus

    PubMed Central

    Stiebler, Renata; Majerowicz, David; Knudsen, Jens; Gondim, Katia C.; Wright, David W.; Egan, Timothy J.; Oliveira, Marcus F.

    2014-01-01

    Hemozoin (Hz) is a heme crystal produced by some blood-feeding organisms, as an efficient way to detoxify heme derived from hemoglobin digestion. In the triatomine insect Rhodnius prolixus, Hz is essentially produced by midgut extracellular phospholipid membranes known as perimicrovillar membranes (PMVM). Here, we investigated the role of commercial glycerophospholipids containing serine, choline and ethanolamine as headgroups and R. prolixus midgut lipids (RML) in heme crystallization. All commercial unsaturated forms of phospholipids, as well as RML, mediated fast and efficient β-hematin formation by means of two kinetically distinct mechanisms: an early and fast component, followed by a late and slow one. The fastest reactions observed were induced by unsaturated forms of phosphatidylethanolamine (uPE) and phosphatidylcholine (uPC), with half-lives of 0.04 and 0.7 minutes, respectively. β-hematin crystal morphologies were strikingly distinct among groups, with uPE producing homogeneous regular brick-shaped crystals. Interestingly, uPC-mediated reactions resulted in two morphologically distinct crystal populations: one less representative group of regular crystals, resembling those induced by uPE, and the other largely represented by crystals with numerous sharp edges and tapered ends. Heme crystallization reactions induced by RML were efficient, with a heme to β-hematin conversion rate higher than 70%, but clearly slower (t1/2 of 9.9–17.7 minutes) than those induced by uPC and uPE. Interestingly, crystals produced by RML were homogeneous in shape and quite similar to those mediated by uPE. Thus, β-hematin formation can be rapidly and efficiently induced by unsaturated glycerophospholipids, particularly uPE and uPC, and may play a role on biological heme crystallization in R. prolixus midgut. PMID:24586467

  18. Transmitting biological effects of stress in utero: implications for mother and offspring.

    PubMed

    Reynolds, Rebecca M; Labad, Javier; Buss, Claudia; Ghaemmaghami, Pearl; Räikkönen, Katri

    2013-09-01

    The developing foetus makes adaptations to an adverse in utero environment which may lead to permanent changes in structure and physiology, thus 'programming' the foetus to risk of ill health in later life. Epidemiological studies have shown associations between low birth weight, a surrogate marker of an adverse intrauterine environment, and a range of diseases in adult life including cardiometabolic and psychiatric disease. These associations do not apply exclusively to low birth weight babies but also to newborns within the normal birth weight range. Early life stress, including stressors in the prenatal and early postnatal period, is a key factor that can have long-term effects on offspring health. Animal studies show this is mediated through changes in the maternal and foetal hypothalamic-pituitary-adrenal axes resulting in foetal exposure to excess glucocorticoids. Data in humans are more limited but support that the biological effects of stress in utero may be transmitted through changes in glucocorticoid action or metabolism. Common contemporary physical and social stressors of maternal obesity and socio-economic deprivation impact on the maternal response to pregnancy and the prevailing hormonal milieu that the developing foetus will be exposed to. Prenatal stress may also be compounded by early postnatal stresses such as childhood maltreatment with resultant adverse effects for the offspring. Understanding of the mechanisms whereby these stressors are transmitted from mother to foetus will not only improve our knowledge of normal foetal development but will also help identify novel pathways for early intervention either in the periconceptional, pregnancy or the early postpartum period.

  19. Biological Implications in Cassava for the Production of Amylose-Free Starch: Impact on Root Yield and Related Traits

    PubMed Central

    Karlström, Amanda; Calle, Fernando; Salazar, Sandra; Morante, Nelson; Dufour, Dominique; Ceballos, Hernán

    2016-01-01

    Cassava (Manihot esculenta, Crantz) is an important food security crop, but it is becoming an important raw material for different industrial applications. Cassava is the second most important source of starch worldwide. Novel starch properties are of interest to the starch industry, and one them is the recently identified amylose-free (waxy) cassava starch. Waxy mutants have been found in different crops and have been often associated with a yield penalty. There are ongoing efforts to develop commercial cassava varieties with amylose-free starch. However, little information is available regarding the biological and agronomic implications of starch mutations in cassava, nor in other root and tuber crops. In this study, siblings from eight full-sib families, segregating for the waxy trait, were used to determine if the mutation has implications for yield, dry matter content (DMC) and harvest index in cassava. A total of 87 waxy and 87 wild-type starch genotypes from the eight families were used in the study. The only significant effect of starch type was on DMC (p < 0.01), with waxy clones having a 0.8% lower content than their wild type counterparts. There was no effect of starch type on fresh root yield (FRY), adjusted FRY and harvest index. It is not clear if lower DMC is a pleiotropic effect of the waxy starch mutation or else the result of linked genes introgressed along with the mutation. It is expected that commercial waxy cassava varieties will have competitive FRYs but special efforts will be required to attain adequate DMCs. This study contributes to the limited knowledge available of the impact of starch mutations on the agronomic performance of root and tuber crops. PMID:27242813

  20. The biological, clinical and prognostic implications of p53 transcriptional pathways in breast cancers.

    PubMed

    Abdel-Fatah, Tarek M; Powe, Desmond G; Agboola, Johnson; Adamowicz-Brice, Martyna; Blamey, Roger W; Lopez-Garcia, Maria A; Green, Andrew R; Reis-Filho, Jorge S; Ellis, Ian O

    2010-03-01

    We hypothesized that the functional status of p53 transcriptional pathways, rather than p53 protein expression alone, could accurately discriminate between low- and high-risk breast carcinoma (BC) and inform about individuals' tumour biological behaviour. To test this, we studied a well-characterized series of 990 BCs with long-term follow-up, immunohistochemically profiled for p53, its main regulators and downstream genes. Results were validated in an independent series of patients (n = 245) uniformly treated with adjuvant anthracycline-based chemotherapy. Eleven p53 transcriptional phenotypes were identified with just two main clinical outcomes. (a) Low risk/good prognosis group (active/partially inactive p53 pathways), defined as p53(+/-)/MDM4(+)/MDM2(+/-)/Bcl2(+/-)/p21(+/-), p53(-)/MDM4(-)/MDM2(+)/Bcl2(+)/p21(+/-) and p53(+/-)/MDM4(-)/MMD2(-)/Bcl2(+)/p21(+/-). These tumours had favourable clinicopathological characteristics, including ER(+) and long survival after systemic adjuvant-therapy (AT). (b) High risk/poor prognosis group (completely inactive p53 pathways), defined as p53(+/-)/MDM4(-) MDM2(-)/Bcl2(-)/p21(-), p53(-)/MDM4(-) MDM2(+)/Bcl2(-)/p21(-) and p53(+/-)/MDM4(-)/MDM2(-)/Bcl2(-)/p21(+). These tumours were characterized by aggressive clinicopathological characteristics and showed shortened survival when treated with AT. Completely inactive p53 pathways but intact p21 axis p53(+/-)/MDM4(-)/MDM2(-)/Bcl2(-)/p21(+) had the worst prognosis, particularly patients who received AT. Multivariate Cox regression models, including validated prognostic factors for both test and validation series, revealed that the functional status of p53 transcriptional pathways was an independent prognosticator for BC-specific survival (HR 2.64 and 4.5, p < 0.001, respectively) and disease-free survival (HR 1.93 and 2.5, p < 0.001, respectively). In conclusion, p53 functional status determined by assessment of p53 regulatory and downstream targets provides independent prognostic

  1. In-situ time resolved studies of apatite formation pathways - implications for biological and environmental systems

    NASA Astrophysics Data System (ADS)

    Borkiewicz, O.; Rakovan, J.; Cahill, C. L.

    2006-05-01

    have been published. The presence of brushite in the initial precipitate and the formation of monetite, as an intermediate phase, have not been observed previously and may be of great importance for apatite crystallization under environmental and biological conditions. Furthermore, precursor formation has never been addressed in the context of heavy metal sequestration by PIMS. The compatibility of the heavy metals with initially formed brushite and intermediate monetite may ultimately be of greater significance for the fate and transport of these toxic species in the environment than their compatibility with apatite.

  2. Extracorporeal blood oxygenation and ozonation: clinical and biological implications of ozone therapy.

    PubMed

    Di Paolo, N; Gaggiotti, E; Galli, F

    2005-01-01

    Some lines of evidence have suggested that the challenge to antioxidants and biomolecules provoked by pro-oxidants such as ozone may be used to generate a controlled stress response of possible therapeutic relevance in some immune dysfunctions and chronic, degenerative conditions. Immune and endothelial cells have been proposed to be elective targets of the positive molecular effects of ozone and its derived species formed during blood ozonation. On the bases of these underlying principles and against often prejudicial scepticism and concerns about its toxicity, ozone has been used in autohemotherapy (AHT) for four decades with encouraging results. However, clinical application and validation of AHT have been so far largely insufficient. Latterly, a new and more effective therapeutic approach to ozone therapy has been established, namely extracorporeal blood oxygenation and ozonation (EBOO). This technique, first tested in vitro and then in vivo in sheep and humans (more than 1200 treatments performed in 82 patients), is performed with a high-efficiency apparatus that makes it possible to treat with a mixture of oxygen-ozone (0.5-1 microg/ml oxygen) in 1 h of extracorporeal circulation up to 4800 ml of heparinized blood without technical or clinical problems, whereas only 250 ml of blood can be treated with ozone by AHT. The EBOO technique can be easily adapted for use in hemodialysis also. The standard therapeutic cycle lasts for 7 weeks in which 14 treatment sessions of 1 h are performed. After a session of EBOO, the interaction of ozone with blood components results in 4-5-fold increased levels of thiobarbituric acid reactants and a proportional decrease in plasma protein thiols without any appreciable erythrocyte haemolysis. On the basis of preliminary in vitro evidence, these simple laboratory parameters may represent a useful complement in the routine monitoring of biological compliance to the treatment. The clinical experience gained so far confirms the

  3. Energy implications of mechanical and mechanical–biological treatment compared to direct waste-to-energy

    SciTech Connect

    Cimpan, Ciprian Wenzel, Henrik

    2013-07-15

    Highlights: • Compared systems achieve primary energy savings between 34 and 140 MJ{sub primary}/100 MJ{sub input} {sub waste.} • Savings magnitude is foremost determined by chosen primary energy and materials production. • Energy consumption and process losses can be upset by increased technology efficiency. • Material recovery accounts for significant shares of primary energy savings. • Direct waste-to-energy is highly efficient if cogeneration (CHP) is possible. - Abstract: Primary energy savings potential is used to compare five residual municipal solid waste treatment systems, including configurations with mechanical (MT) and mechanical–biological (MBT) pre-treatment, which produce waste-derived fuels (RDF and SRF), biogas and/or recover additional materials for recycling, alongside a system based on conventional mass burn waste-to-energy and ash treatment. To examine the magnitude of potential savings we consider two energy efficiency levels (state-of-the-art and best available technology), the inclusion/exclusion of heat recovery (CHP vs. PP) and three different background end-use energy production systems (coal condensing electricity and natural gas heat, Nordic electricity mix and natural gas heat, and coal CHP energy quality allocation). The systems achieved net primary energy savings in a range between 34 and 140 MJ{sub primary}/100 MJ{sub input} {sub waste}, in the different scenario settings. The energy footprint of transportation needs, pre-treatment and reprocessing of recyclable materials was 3–9.5%, 1–18% and 1–8% respectively, relative to total energy savings. Mass combustion WtE achieved the highest savings in scenarios with CHP production, nonetheless, MBT-based systems had similarly high performance if SRF streams were co-combusted with coal. When RDF and SRF was only used in dedicated WtE plants, MBT-based systems totalled lower savings due to inherent system losses and additional energy costs. In scenarios without heat

  4. Energy implications of mechanical and mechanical-biological treatment compared to direct waste-to-energy.

    PubMed

    Cimpan, Ciprian; Wenzel, Henrik

    2013-07-01

    Primary energy savings potential is used to compare five residual municipal solid waste treatment systems, including configurations with mechanical (MT) and mechanical-biological (MBT) pre-treatment, which produce waste-derived fuels (RDF and SRF), biogas and/or recover additional materials for recycling, alongside a system based on conventional mass burn waste-to-energy and ash treatment. To examine the magnitude of potential savings we consider two energy efficiency levels (state-of-the-art and best available technology), the inclusion/exclusion of heat recovery (CHP vs. PP) and three different background end-use energy production systems (coal condensing electricity and natural gas heat, Nordic electricity mix and natural gas heat, and coal CHP energy quality allocation). The systems achieved net primary energy savings in a range between 34 and 140 MJprimary/100 MJinput waste, in the different scenario settings. The energy footprint of transportation needs, pre-treatment and reprocessing of recyclable materials was 3-9.5%, 1-18% and 1-8% respectively, relative to total energy savings. Mass combustion WtE achieved the highest savings in scenarios with CHP production, nonetheless, MBT-based systems had similarly high performance if SRF streams were co-combusted with coal. When RDF and SRF was only used in dedicated WtE plants, MBT-based systems totalled lower savings due to inherent system losses and additional energy costs. In scenarios without heat recovery, the biodrying MBS-based system achieved the highest savings, on the condition of SRF co-combustion. As a sensitivity scenario, alternative utilisation of SRF in cement kilns was modelled. It supported similar or higher net savings for all pre-treatment systems compared to mass combustion WtE, except when WtE CHP was possible in the first two background energy scenarios. Recovery of plastics for recycling before energy recovery increased net energy savings in most scenario variations, over those of full

  5. Student learning style preferences in college-level biology courses: Implications for teaching and academic performance

    NASA Astrophysics Data System (ADS)

    Sitton, Jennifer Susan

    Education research has focused on defining and identifying student learning style preferences and how to incorporate this knowledge into teaching practices that are effective in engaging student interest and transmitting information. One objective was determining the learning style preferences of undergraduate students in Biology courses at New Mexico State University by using the online VARK Questionnaire and an investigator developed survey (Self Assessed Learning Style Survey, LSS). Categories include visual, aural, read-write, kinesthetic, and multimodal. The courses differed in VARK single modal learning preferences (p = 0.035) but not in the proportions of the number of modes students preferred (p = 0.18). As elsewhere, the majority of students were multimodal. There were similarities and differences between LSS and VARK results and between students planning on attending medical school and those not. Preferences and modalities tended not to match as expected for ratings of helpfulness of images and text. To detect relationships between VARK preferred learning style and academic performance, ANOVAs were performed using modality preferences and normalized learning gains from pre and post tests over material taught in the different modalities, as well as on end of semester laboratory and lecture grades. Overall, preference did not affect the performance for a given modality based activity, quiz, or final lecture or laboratory grades (p > 0.05). This suggests that a student's preference does not predict an improved performance when supplied with material in that modality. It is recommended that methods be developed to aid learning in a variety of modalities, rather than catering to individual learning styles. Another topic that is heavily debated in the field of education is the use of simulations or videos to replace or supplement dissections. These activities were compared using normalized learning gains from pre and post tests, as well as attitude surveys

  6. A Transcriptomic Analysis of Echinococcus granulosus Larval Stages: Implications for Parasite Biology and Host Adaptation

    PubMed Central

    Parkinson, John; Wasmuth, James D.; Salinas, Gustavo; Bizarro, Cristiano V.; Sanford, Chris; Berriman, Matthew; Ferreira, Henrique B.; Zaha, Arnaldo; Blaxter, Mark L.; Maizels, Rick M.; Fernández, Cecilia

    2012-01-01

    Background The cestode Echinococcus granulosus - the agent of cystic echinococcosis, a zoonosis affecting humans and domestic animals worldwide - is an excellent model for the study of host-parasite cross-talk that interfaces with two mammalian hosts. To develop the molecular analysis of these interactions, we carried out an EST survey of E. granulosus larval stages. We report the salient features of this study with a focus on genes reflecting physiological adaptations of different parasite stages. Methodology/Principal Findings We generated ∼10,000 ESTs from two sets of full-length enriched libraries (derived from oligo-capped and trans-spliced cDNAs) prepared with three parasite materials: hydatid cyst wall, larval worms (protoscoleces), and pepsin/H+-activated protoscoleces. The ESTs were clustered into 2700 distinct gene products. In the context of the biology of E. granulosus, our analyses reveal: (i) a diverse group of abundant long non-protein coding transcripts showing homology to a middle repetitive element (EgBRep) that could either be active molecular species or represent precursors of small RNAs (like piRNAs); (ii) an up-regulation of fermentative pathways in the tissue of the cyst wall; (iii) highly expressed thiol- and selenol-dependent antioxidant enzyme targets of thioredoxin glutathione reductase, the functional hub of redox metabolism in parasitic flatworms; (iv) candidate apomucins for the external layer of the tissue-dwelling hydatid cyst, a mucin-rich structure that is critical for survival in the intermediate host; (v) a set of tetraspanins, a protein family that appears to have expanded in the cestode lineage; and (vi) a set of platyhelminth-specific gene products that may offer targets for novel pan-platyhelminth drug development. Conclusions/Significance This survey has greatly increased the quality and the quantity of the molecular information on E. granulosus and constitutes a valuable resource for gene prediction on the parasite genome

  7. The ISRU Field Tests 2010 and 2012 at Mauna Kea, Hawaii: Results from the Miniaturised Mossbauer Spectrometers Mimos II and Mimos IIA

    NASA Technical Reports Server (NTRS)

    Klingelhoefer, G.; Morris, R. V.; Blumers, M; Bernhardt, B.; Graff, T.

    2014-01-01

    The 2010 and 2012 In-Situ Resource Utilization Analogue Test (ISRU) [1] on the Mauna Kea volcano in Hawai'i was coordinated by the Northern Centre for Advanced Technology (NORCAT) in collaboration with the Canadian Space Agency (CSA), the German Aerospace Center (DLR), and the National Aeronautics and Space Administration (NASA), through the PISCES program. Several instruments were tested as reference candidates for future analogue testing at the new field test site at the Mauna Kea volcano in Hawai'i. The fine-grained, volcanic nature of the material is a suitable lunar and martian analogue, and can be used to test excavation, site preparation, and resource utilization techniques. The 2010 location Pu'u Hiwahine, a cinder cone located below the summit of Mauna Kea (19deg45'39.29" N, 155deg28'14.56" W) at an elevation of 2800 m, provides a large number of slopes, rock avalanches, etc. to perform mobility tests, site preparation or resource prospecting. Besides hardware testing of technologies and systems related to resource identification, also in situ science measurements played a significant role in integration of ISRU and science instruments. For the advanced Mössbauer instrument MIMOS IIA, the new detector technologies and electronic components increase sensitivity and performance significantly. In combination with the high energy resolution of the SDD it is possible to perform Xray fluorescence analysis simultaneously to Mössbauer spectroscopy. In addition to the Fe-mineralogy, information on the sample's elemental composition will be gathered. The 2010 and 2012 field campaigns demonstrated that in-situ Mössbauer spectroscopy is an effective tool for both science and feedstock exploration and process monitoring. Engineering tests showed that a compact nickel metal hydride battery provided sufficient power for over 12 hr of continuous operation for the MIMOS instruments.

  8. A Systems Biology Comparison of Ovarian Cancers Implicates Putative Somatic Driver Mutations through Protein-Protein Interaction Models

    PubMed Central

    Yang, Mary Qu; Elnitski, Laura

    2016-01-01

    Ovarian carcinomas can be aggressive with a high mortality rate (e.g., high-grade serous ovarian carcinomas, or HGSOCs), or indolent with much better long-term outcomes (e.g., low-malignant-potential, or LMP, serous ovarian carcinomas). By comparing LMP and HGSOC tumors, we can gain insight into the mechanisms underlying malignant progression in ovarian cancer. However, previous studies of the two subtypes have been focused on gene expression analysis. Here, we applied a systems biology approach, integrating gene expression profiles derived from two independent data sets containing both LMP and HGSOC tumors with protein-protein interaction data. Genes and related networks implicated by both data sets involved both known and novel disease mechanisms and highlighted the different roles of BRCA1 and CREBBP in the two tumor types. In addition, the incorporation of somatic mutation data revealed that amplification of PAK4 is associated with poor survival in patients with HGSOC. Thus, perturbations in protein interaction networks demonstrate differential trafficking of network information between malignant and benign ovarian cancers. The novel network-based molecular signatures identified here may be used to identify new targets for intervention and to improve the treatment of invasive ovarian cancer as well as early diagnosis. PMID:27788148

  9. Reproductive biology of Ilisha elongata (Teleostei: Pristigasteridae) in Ariake Sound, Japan: Implications for estuarine fish conservation in Asia

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Takita, Toru; Zhang, Chunguang

    2009-01-01

    Elongate ilisha ( Ilisha enlongata) is a commercially important species that contributes to clupeoid fisheries in Asian countries. In the present study, the reproductive biology of I. elongata in Ariake Sound, Japan is determined for the first time. Six maturity stages were described using ovarian and testicular histology throughout the annual cycle. The spawning season in Ariake Sound lasts from May to July, with peak spawning activity in May and June. Age at first maturity was estimated to be 2 years, with a few exceptions of 1 year in well-developed males. Ovaries that contained both tertiary yolk oocytes and postovulatory follicles occurred from late May to late July, indicating that I. elongata is a multiple spawner. The size-frequency distribution of oocytes provided evidence for its multiple spawning and accuracy of the fecundity estimates. The batch fecundity of this species was estimated at between 22,200 and 270,900 eggs per individual, increasing with age between two and six years. The present findings on the reproductive strategy of I. elongata in Ariake Sound are generally consistent with those in temperate or subtropical populations, but quite different from those of tropical population where first maturation occurs around 200 days and life spans are shorter, with a maximum age less than 3 years. The conservation implications of this reproductive strategy in a harsh, variable environment in Asian countries are also discussed.

  10. Characterization and reactivity of the weakly bound complexes of the [H, N, S]- anionic system with astrophysical and biological implications

    NASA Astrophysics Data System (ADS)

    Trabelsi, T.; Ajili, Y.; Ben Yaghlane, S.; Jaidane, N.-E.; Mogren Al-Mogren, M.; Francisco, J. S.; Hochlaf, M.

    2015-07-01

    We investigate the lowest electronic states of doublet and quartet spin multiplicity states of HNS- and HSN- together with their parent neutral triatomic molecules. Computations were performed using highly accurate ab initio methods with a large basis set. One-dimensional cuts of the full-dimensional potential energy surfaces (PESs) along the interatomic distances and bending angle are presented for each isomer. Results show that the ground anionic states are stable with respect to the electron detachment process and that the long range parts of the PESs correlating to the SH- + N, SN- + H, SN + H-, NH + S-, and NH- + S are bound. In addition, we predict the existence of long-lived weakly bound anionic complexes that can be formed after cold collisions between SN- and H or SH- and N. The implications for the reactivity of these species are discussed; specifically, it is shown that the reactions involving SH-, SN-, and NH- lead either to the formation of HNS- or HSN- in their electronic ground states or to autodetachment processes. Thus, providing an explanation for why the anions, SH-, SN-, and NH-, have limiting detectability in astrophysical media despite the observation of their corresponding neutral species. In a biological context, we suggest that HSN- and HNS- should be incorporated into H2S-assisted heme-catalyzed reduction mechanism of nitrites in vivo.

  11. Biological soil crusts exhibit a dynamic response to seasonal rain and release from grazing with implications for soil stability

    USGS Publications Warehouse

    Jimenez, Aguilar A.; Huber-Sannwald, E.; Belnap, J.; Smart, D.R.; Arredondo, Moreno J.T.

    2009-01-01

    In Northern Mexico, long-term grazing has substantially degraded semiarid landscapes. In semiarid systems, ecological and hydrological processes are strongly coupled by patchy plant distribution and biological soil crust (BSC) cover in plant-free interspaces. In this study, we asked: 1) how responsive are BSC cover/composition to a drying/wetting cycle and two-year grazing removal, and 2) what are the implications for soil erosion? We characterized BSC morphotypes and their influence on soil stability under grazed/non-grazed conditions during a dry and wet season. Light- and dark-colored cyanobacteria were dominant at the plant tussock and community level. Cover changes in these two groups differed after a rainy season and in response to grazing removal. Lichens with continuous thalli were more vulnerable to grazing than those with semi-continuous/discontinuous thalli after the dry season. Microsites around tussocks facilitated BSC colonization compared to interspaces. Lichen and cyanobacteria morphotypes differentially enhanced resistance to soil erosion; consequently, surface soil stability depends on the spatial distribution of BSC morphotypes, suggesting soil stability may be as dynamic as changes in the type of BSC cover. Longer-term spatially detailed studies are necessary to elicit spatiotemporal dynamics of BSC communities and their functional role in biotically and abiotically variable environments. ?? 2009 Elsevier Ltd.

  12. Nicotine dose-concentration relationship and pregnancy outcomes in rat: Biologic plausibility and implications for future research

    SciTech Connect

    Hussein, Jabeen; Farkas, Svetlana; MacKinnon, Yolanda; Ariano, Robert E.; Sitar, Daniel S.; Hasan, Shabih U. . E-mail: hasans@ucalgary.ca

    2007-01-01

    Cigarette smoke (CS) exposure during pregnancy can lead to profound adverse effects on fetal development. Although CS contains several thousand chemicals, nicotine has been widely used as its surrogate as well as in its own right as a neuroteratogen. The justification for the route and dose of nicotine administration is largely based on inferential data suggesting that nicotine 6 mg/kg/day infused continuously via osmotic mini pumps (OMP) would mimic maternal CS exposure. We provide evidence that 6 mg/kg/day nicotine dose as commonly administered to pregnant rats leads to plasma nicotine concentrations that are 3-10-fold higher than those observed in moderate to heavy smokers and pregnant mothers, respectively. Furthermore, the cumulative daily nicotine dose exceeds by several hundred fold the amount consumed by human heavy smokers. Our study does not support the widely accepted notion that regardless of the nicotine dose, a linear nicotine dose-concentration relationship exists in a steady-state OMP model. We also show that total nicotine clearance increases with advancing pregnancy but no significant change is observed between the 2nd and 3rd trimester. Furthermore, nicotine infusion even at this extremely high dose has little effect on a number of maternal and fetal biologic variables and pregnancy outcome suggesting that CS constituents other than nicotine mediate the fetal growth restriction in infants born to smoking mothers. Our current study has major implications for translational research in developmental toxicology and pharmacotherapy using nicotine replacement treatment as an aid to cessation of cigarette smoking in pregnant mothers.

  13. The Basic Biology of Redoxosomes in Cytokine-Mediated Signal Transduction and Implications for Disease-Specific Therapies

    PubMed Central

    2015-01-01

    Redox reactions have been established as major biological players in many cellular signaling pathways. Here we review mechanisms of redox signaling with an emphasis on redox-active signaling endosomes. Signals are transduced by relatively few reactive oxygen species (ROS), through very specific redox modifications of numerous proteins and enzymes. Although ROS signals are typically associated with cellular injury, these signaling pathways are also critical for maintaining cellular health at homeostasis. An important component of ROS signaling pertains to localization and tightly regulated signal transduction events within discrete microenvironments of the cell. One major aspect of this specificity is ROS compartmentalization within membrane-enclosed organelles such as redoxosomes (redox-active endosomes) and the nuclear envelope. Among the cellular proteins that produce superoxide are the NADPH oxidases (NOXes), transmembrane proteins that are implicated in many types of redox signaling. NOXes produce superoxide on only one side of a lipid bilayer; as such, their orientation dictates the compartmentalization of ROS and the local control of signaling events limited by ROS diffusion and/or movement through channels associated with the signaling membrane. NOX-dependent ROS signaling pathways can also be self-regulating, with molecular redox sensors that limit the local production of ROS required for effective signaling. ROS regulation of the Rac-GTPase, a required co-activator of many NOXes, is an example of this type of sensor. A deeper understanding of redox signaling pathways and the mechanisms that control their specificity will provide unique therapeutic opportunities for aging, cancer, ischemia-reperfusion injury, and neurodegenerative diseases. PMID:24555469

  14. High abundances of oxalic, azelaic, and glyoxylic acids and methylglyoxal in the open ocean with high biological activity: Implication for secondary OA formation from isoprene

    NASA Astrophysics Data System (ADS)

    Bikkina, Srinivas; Kawamura, Kimitaka; Miyazaki, Yuzo; Fu, Pingqing

    2014-05-01

    Atmospheric dicarboxylic acids (DCA) are a ubiquitous water-soluble component of secondary organic aerosols (SOA), which can act as cloud condensation nuclei (CCN), affecting the Earth's climate. Despite the high abundances of oxalic acid and related compounds in the marine aerosols, there is no consensus on what controls their distributions over the open ocean. Marine biological productivity could play a role in the production of DCA, but there is no substantial evidence to support this hypothesis. Here we present latitudinal distributions of DCA, oxoacids and α-dicarbonyls in the marine aerosols from the remote Pacific. Their concentrations were found several times higher in more biologically influenced aerosols (MBA) than less biologically influenced aerosols. We propose isoprene and unsaturated fatty acids as sources of DCA as inferred from significantly higher abundances of isoprene-SOA tracers and azelaic acid in MBA. These results have implications toward the reassessment of climate forcing feedbacks of marine-derived SOA.

  15. In Situ Resource Utilization (ISRU) on the Moon: Moessbauer Spectroscopy as a Process Monitor for Oxygen Production. Results from a Field Test on Mauna Kea Volcano, Hawaii

    NASA Technical Reports Server (NTRS)

    Morris, R.V.; Schroder, C.; Graff, T.G.; Sanders, G.B.; Lee, K.A.; Simon, T.M.; Larson, W.E.; Quinn, J.W.; Clark, L.D.; Caruso, J.J.

    2009-01-01

    Essential consumables like oxygen must to be produced from materials on the lunar surface to enable a sustained, long-term presence of humans on the Moon. The Outpost Precursor for ISRU and Modular Architecture (OPTIMA) field test on Mauna Kea, Hawaii, facilitated by the Pacific International Space Center for Exploration Systems (PISCES) of the University of Hawaii at Hilo, was designed to test the implementation of three hardware concepts to extract oxygen from the lunar regolith: Precursor ISRU Lunar Oxygen Testbed (PILOT) developed by Lockheed Martin in Littleton, CO; Regolith & Environmental Science and Oxygen & Lunar Volatiles Extraction (RESOLVE) developed at the NASA Kennedy Space Center in Cape Canaveral, FL; and ROxygen developed at the NASA Johnson Space Center in Houston, TX. The three concepts differ in design, but all rely on the same general principle: hydrogen reduction of metal cations (primarily Fe2+) bonded to oxygen to metal (e.g., Fe0) with the production of water. The hydrogen source is residual hydrogen in the fuel tanks of lunar landers. Electrolysis of the water produces oxygen and hydrogen (which is recycled). We used the miniaturized M ssbauer spectrometer MIMOS II to quantify the yield of this process on the basis of the quantity of Fe0 produced. Iron M ssbauer spectroscopy identifies iron-bearing phases, determines iron oxidation states, and quantifies the distribution of iron between mineral phases and oxidation states. The oxygen yield can be calculated by quantitative measurements of the distribution of Fe among oxidation states in the regolith before and after hydrogen reduction. A M ssbauer spectrometer can also be used as a prospecting tool to select the optimum feedstock for the oxygen production plants (e.g., high total Fe content and easily reduced phases). As a demonstration, a MIMOS II backscatter spectrometer (SPESI, Germany) was mounted on the Cratos rover (NASA Glenn Research Center in Cleveland, OH), which is one of

  16. In Situ Resource Utilization (ISRU) on the Moon: Moessbauer Spectroscopy as a Process Monitor for Oxygen Production. Results from a Field Test on Mauna Kea Volcano, Hawaii

    NASA Technical Reports Server (NTRS)

    Morris, R.V.; Schroder, C.; Graff, T.G.; Sanders, G.B.; Lee, K.A.; Simon, T.M.; Larson, W.E.; Quinn, J.W.; Clark, L.D.; Caruso, J.J.

    2009-01-01

    Essential consumables like oxygen must to be produced from materials on the lunar surface to enable a sustained, long-term presence of humans on the Moon. The Outpost Precursor for ISRU and Modular Architecture (OPTIMA) field test on Mauna Kea, Hawaii, facilitated by the Pacific International Space Center for Exploration Systems (PISCES) of the University of Hawaii at Hilo, was designed to test the implementation of three hardware concepts to extract oxygen from the lunar regolith: Precursor ISRU Lunar Oxygen Testbed (PILOT) developed by Lockheed Martin in Littleton, CO; Regolith & Environmental Science and Oxygen & Lunar Volatiles Extraction (RESOLVE) developed at the NASA Kennedy Space Center in Cape Canaveral, FL; and ROxygen developed at the NASA Johnson Space Center in Houston, TX. The three concepts differ in design, but all rely on the same general principle: hydrogen reduction of metal cations (primarily Fe2+) bonded to oxygen to metal (e.g., Fe0) with the production of water. The hydrogen source is residual hydrogen in the fuel tanks of lunar landers. Electrolysis of the water produces oxygen and hydrogen (which is recycled). We used the miniaturized M ssbauer spectrometer MIMOS II to quantify the yield of this process on the basis of the quantity of Fe0 produced. Iron M ssbauer spectroscopy identifies iron-bearing phases, determines iron oxidation states, and quantifies the distribution of iron between mineral phases and oxidation states. The oxygen yield can be calculated by quantitative measurements of the distribution of Fe among oxidation states in the regolith before and after hydrogen reduction. A M ssbauer spectrometer can also be used as a prospecting tool to select the optimum feedstock for the oxygen production plants (e.g., high total Fe content and easily reduced phases). As a demonstration, a MIMOS II backscatter spectrometer (SPESI, Germany) was mounted on the Cratos rover (NASA Glenn Research Center in Cleveland, OH), which is one of

  17. Gaps in college biology students' understanding of photosynthesis: Implications for human constructivist learning theory and college classroom practice

    NASA Astrophysics Data System (ADS)

    Griffard, Phyllis Baudoin

    1999-11-01

    The main research question of this study was: What gaps in biochemical understanding are revealed by a range of university introductory biology students as they work through a critically acclaimed multimedia program on photosynthesis, and what are the corresponding implications for elaboration of the Ausubel-Novak-Gowin Learning Theory (ANG, now Human Constructivism)? Twelve students, mixed for ability, gender and ethnicity, were recruited from two sections of "Bio 101." Before and after instruction in photosynthesis, in-depth clinical interviews were conducted during which participants completed a range of cognitive tasks such as sorting, concept mapping, explaining and predicting. Some tasks involved interacting with a computer simulation of photosynthesis. This study primarily employed qualitative case study and verbal analysis methods. Verbal analysis of the clinical interviews revealed numerous gaps that were categorized into typologies. The two major categories were propositional gaps and processing gaps. Propositional gaps were evident in development of participants' concepts, links and constructs. Significant among these were conceptual distance gaps and continuity of matter gaps. Gaps such as convention gaps and relative significance gaps seem to be due to naivete in the discipline. Processing gaps included gaps in graphic decoding skills and relevant cognitive habits such as self-monitoring and consulting prior knowledge. Although the gaps were easier to detect and isolate with the above-average participants, all participants showed evidence of at least some of these gaps. Since some gaps are not unexpected at all but the highest literacy levels, not all the gaps identified are to be considered deficiencies. The gaps identified support the attention given by ANG theorists to the role of prior knowledge and metacognition as well as the value of graphic organizers in knowledge construction. In addition, this study revealed numerous gaps in graphic decoding

  18. The Redox Chemistry and Chemical Biology of H2S, Hydropersulfides and Derived Species: Implications to Their Possible Biological Activity and Utility

    PubMed Central

    Ono, Katsuhiko; Akaike, Takaake; Sawa, Tomohiro; Kumagai, Yoshito; Wink, David A.; Tantillo, Dean J.; Hobbs, Adrian J.; Nagy, Peter; Xian, Ming; Lin, Joseph; Fukuto, Jon M.

    2014-01-01

    Hydrogen sulfide (H2S) is an endogenously generated and putative signaling/effector molecule. In spite of its numerous reported functions, the chemistry by which it elicits its functions is not understood. Moreover, recent studies allude to the existence of other sulfur species besides H2S that may play critical physiological roles. Herein, the basic chemical biology of H2S as well as other related or derived species is discussed and reviewed. A particular focus of this review are the per- and poly-sulfides which are likely in equilibrium with free H2S and which may be important biological effectors themselves. PMID:25229186

  19. Differential physiological responses of dalmatian toadflax, Linaria dalmatica L. Miller, to injury from two insect biological control agents: Implications for decision-making in biological control

    Treesearch

    Robert K. D. Peterson; Sharlene E. Sing; David K. Weaver

    2005-01-01

    Successful biological control of invasive weeds with specialist herbivorous insects is predicated on the assumption that the injury stresses the weeds sufficiently to cause reductions in individual fitness. Because plant gas exchange directly impacts growth and fitness, characterizing how injury affects these primary processes may provide a key indicator of...

  20. Regulation of drug-metabolizing enzymes in infectious and inflammatory disease: implications for biologics-small molecule drug interactions.

    PubMed

    Mallick, Pankajini; Taneja, Guncha; Moorthy, Bhagavatula; Ghose, Romi

    2017-06-01

    Drug-metabolizing enzymes (DMEs) are primarily down-regulated during infectious and inflammatory diseases, leading to disruption in the metabolism of small molecule drugs (smds), which are increasingly being prescribed therapeutically in combination with biologics for a number of chronic diseases. The biologics may exert pro- or anti-inflammatory effect, which may in turn affect the expression/activity of DMEs. Thus, patients with infectious/inflammatory diseases undergoing biologic/smd treatment can have complex changes in DMEs due to combined effects of the disease and treatment. Areas covered: We will discuss clinical biologics-SMD interaction and regulation of DMEs during infection and inflammatory diseases. Mechanistic studies will be discussed and consequences on biologic-small molecule combination therapy on disease outcome due to changes in drug metabolism will be highlighted. Expert opinion: The involvement of immunomodulatory mediators in biologic-SMDs is well known. Regulatory guidelines recommend appropriate in vitro or in vivo assessments for possible interactions. The role of cytokines in biologic-SMDs has been documented. However, the mechanisms of drug-drug interactions is much more complex, and is probably multi-factorial. Studies aimed at understanding the mechanism by which biologics effect the DMEs during inflammation/infection are clinically important.

  1. US Food and Drug Administration approval of generic versions of complex biologics: implications for the practicing physician using low molecular weight heparins.

    PubMed

    Cohen, Marc; Jeske, Walter P; Nicolau, Jose C; Montalescot, Gilles; Fareed, Jawed

    2012-04-01

    Low-molecular-weight heparins (LMWHs) have shown equivalent or superior efficacy and safety to unfractionated heparin as antithrombotic therapy for patients with acute coronary syndromes. Each approved LMWH is a pleotropic biological agent with a unique chemical, biochemical, biophysical and biological profile and displays different pharmacodynamic and pharmacokinetic profiles. As a result, LMWHs are neither equipotent in preclinical assays nor equivalent in terms of their clinical efficacy and safety. Previously, the US Food and Drug Administration (FDA) cautioned against using various LMWHs interchangeably, however recently, the FDA approved generic versions of LMWH that have not been tested in large clinical trials. This paper highlights the bio-chemical and pharmacological differences between the LMWH preparations that may result in different clinical outcomes, and also reviews the implications and challenges physicians face when generic versions of the original/innovator agents are approved for clinical use.

  2. Warming and increased precipitation frequency on the Colorado Plateau: Implications for biological soil crusts and soil processes

    USGS Publications Warehouse

    Zelikova, Tamara J.; Housman, David C.; Grote, Ed E.; Neher, Deborah A.; Belnap, Jayne

    2012-01-01

    Taken together, our results highlight the limited effects of warming alone on biological soil crust communities and soil chemistry, but demonstrate the substantially larger effects of altered summertime precipitation.

  3. Experiences of mobility for people living with rheumatoid arthritis who are receiving biologic drug therapy: implications for podiatry services.

    PubMed

    Sanders, Lucy; Donovan-Hall, Margaret; Borthwick, Alan; Bowen, Catherine J

    2017-01-01

    Despite significant advancements in new treatment modalities for rheumatoid arthritis with biological therapies, foot complications remain a disabling and common feature of the disease. In this study the aim was to explore and describe the personal experiences of people with rheumatoid arthritis in receipt of biologic treatments in a bid to understand the impact of this form of medication on their mobility. An interpretative phenomenological analysis (IPA) was undertaken to explore in depth the individual experience of rheumatoid disease through personal accounts of the patient journey spanning both 'before' and 'after' the instigation of biologic therapy. A purposive sampling strategy was adopted and in-depth semi structured interviews used to facilitate rich, detailed interview data exploring the lived experiences of individuals undertaking biological therapy and the changes to mobility experienced as a result. Thematic analysis was employed with an IPA framework to identify key meanings, and report patterns within the data. Five people with rheumatoid arthritis participated in the study. The mean disease duration was 20.2 years (range: 6 -32) and all were being treated with biologic therapies. Four key themes emerged from the data: 1) Life before biologic treatment, depicted in accounts as a negative experience characterised by painful and disabling symptoms and feelings of hopelessness. 2) Life with biologic treatment, often experienced as a life changing transition, restoring function and mobility and offering renewed hope. 3) Sense of self, in which the impact of rheumatoid disease and the subsequent changes arising from biologic therapy reveal a profound impact on feelings of personal identity both pre and post biologic therapy; an effect of footwear on self-image emerges as a dominant sub theme; 4) Unmet footcare needs were evident in the patient narrative, where the unrelenting if diminished impact of foot pain on mobility was viewed in the context of

  4. Influence of Temperature on the Reproductive and Developmental Biology of Ontsira mellipes (Hymenoptera: Braconidae): Implications for Biological Control of the Asian Longhorned Beetle (Coleoptera: Cerambycidae).

    PubMed

    Golec, Julian R; Duan, Jian J; Hough-Goldstein, Judith

    2017-08-01

    Ontsira mellipes Ashmead (Hymenoptera: Braconidae) is a North American parasitoid species that develops on the invasive pest, Anoplophora glabripennis (Moltschulsky) (Coleoptera: Cerambycidae), under laboratory conditions and is currently being considered as a potential new-association biocontrol agent. To develop mass-rearing protocols and field-release strategies for this parasitoid, information on its reproductive biology in relation to temperature is needed. We determined the effect of temperature (10, 15, 20, 25, and 30 °C) on development, survivorship, and sex ratio, and its effect on the longevity, fecundity, and host attack rates (parasitism) of adults. Developmental time for parasitoid eggs to pupae decreased from 26.7 d to 6.1 d as temperature increased from 10 °C to 30 °C. While no pupae eclosed as adults at 10 °C, time of adult emergence from pupae decreased from 39.7 d to 12.2 d as temperature increased from 15 °C to 30 °C. Based on estimated lower development temperature threshold (11.1 °C), the degree-days required for one generation was estimated at 342.9. When female parasitoids were provided with host larvae, parasitism occurred at all temperatures and was maximized at 25 °C. Additionally, increasing temperatures significantly reduced the preoviposition period and longevity of female O. mellipes. In addition, combining these results with temperature data from areas in the United States currently infested with A. glabripennis, we estimated that O. mellipes can complete 1.2-3.7 generations per year. Findings from this study may be considered for the future development of effective mass rearing and augmentative release strategies of O. mellipes for biological control of A. glabripennis. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

  5. Policy implications of select student characteristics and their influence on the Florida biology end-of-course assessment

    NASA Astrophysics Data System (ADS)

    Bertolotti, Janine Cecelia

    In an attempt to improve student achievement in science in Florida, the Florida Department of Education implemented end-of-course (EOC) assessments in biology during the 2011-2012 academic school year. Although this first administration would only account for 30% of the student's overall final course grade in biology, subsequent administrations would be accompanied by increasing stakes for students, teachers, and schools. Therefore, this study sought to address gaps in empirical evidence as well as discuss how educational policy will potentially impact on teacher evaluation and professional development, student retention and graduation rates, and school accountability indicators. This study explored four variables- reading proficiency, ethnicity, socioeconomic status, and gender- to determine their influence and relationship on biology achievement on the Biology I EOC assessment at a Title 1 school. To do so, the results of the Biology I EOC assessment administered during the Spring 2012 school year was obtained from a small, rural Title 1 high school in North Florida. Additional data regarding each student's qualification for free and reduced-price lunch, FCAT Reading developmental scale scores, FCAT Reading level, grade level, gender, and ethnicity were also collected for the causal-comparative exploratory study. Of the 178 students represented, 48% qualified for free and reduced-price lunch, 54% were female, and 55% scored at FCAT Reading level 3 or higher. Additionally, 59% were White and 37% Black. A combination of descriptive statistics and other statistical procedures such as independent samples one-tailed t-test, one-way ANOVAs, ANCOVAs, multipleregression, and a Pearson r correlation was utilized in the analysis, with a significance level set at 0.05. Results indicate that of all four variables, FCAT Reading proficiency was the sole variable, after adjusting for other variables; that had a significant impact on biology achievement. Students with higher

  6. Biological Effects Induced by Non-thermal Ultrasound and Implications for Cancer Therapy: A Review of the Current Literature.

    PubMed

    Tang, Justin; Guha, Chandan; Tomé, Wolfgang A

    2015-04-01

    Recent advancements in imaging and targeting have expanded the utility of ultrasound therapy with increasing attention being paid to the application of ultrasound in cancer therapy. We present in this article a review of the biological effects of non-thermal ultrasound that could find application in cancer treatment in the near and long term. A careful examination of the ultrasound parameters that elicited these observed effects is needed so that one may refine and apply these results for clinical application. Reported biological effects from non-thermal ultrasound have been categorized into mechanical and chemical means of action. Cavitation and acoustic radiation force are the main contributors to sonomechanical effects of ultrasound while reactive oxygen species contribute to its sonochemical effects. These two categories are responsible for observations such as induction of apoptosis in cancer cells, disturbance of the cytoskeleton, enhancement of gene transfection and chemotherapeutic potency, and modulation of cellular proliferation and protein synthesis. In this review we have considered the biological effects of non-thermal ultrasound, the range of parameters at which these biological effects are observed, and the applicability of the observed biological effects to cancer therapy. © The Author(s) 2014.

  7. Shared ACVR1 mutations in FOP and DIPG: Opportunities and challenges in extending biological and clinical implications across rare diseases.

    PubMed

    Han, Harry J; Jain, Payal; Resnick, Adam C

    2017-08-02

    Gain-of-function mutations in the Type I Bone Morphogenic Protein (BMP) receptor ACVR1 have been identified in two diseases: Fibrodysplasia Ossificans Progressiva (FOP), a rare autosomal dominant disorder characterized by genetically driven heterotopic ossification, and in 20-25% of Diffuse Intrinsic Pontine Gliomas (DIPGs), a pediatric brain tumor with no effective therapies and dismal median survival. While the ACVR1 mutation is causal for FOP, its role in DIPG tumor biology remains under active investigation. Here, we discuss cross-fertilization between the FOP and DIPG fields, focusing on the biological mechanisms and principles gleaned from FOP that can be applied to DIPG biology. We highlight our current knowledge of ACVR1 in both diseases, and then describe the growing opportunities and barriers to effectively investigate ACVR1 in DIPG. Importantly, learning from other seemingly unrelated diseases harboring similar mutations may uncover novel mechanisms or processes for future investigation. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. The implications of non-linear biological oscillations on human electrophysiology for electrohypersensitivity (EHS) and multiple chemical sensitivity (MCS).

    PubMed

    Sage, Cindy

    2015-01-01

    The 'informational content' of Earth's electromagnetic signaling is like a set of operating instructions for human life. These environmental cues are dynamic and involve exquisitely low inputs (intensities) of critical frequencies with which all life on Earth evolved. Circadian and other temporal biological rhythms depend on these fluctuating electromagnetic inputs to direct gene expression, cell communication and metabolism, neural development, brainwave activity, neural synchrony, a diversity of immune functions, sleep and wake cycles, behavior and cognition. Oscillation is also a universal phenomenon, and biological systems of the heart, brain and gut are dependent on the cooperative actions of cells that function according to principles of non-linear, coupled biological oscillations for their synchrony. They are dependent on exquisitely timed cues from the environment at vanishingly small levels. Altered 'informational content' of environmental cues can swamp natural electromagnetic cues and result in dysregulation of normal biological rhythms that direct growth, development, metabolism and repair mechanisms. Pulsed electromagnetic fields (PEMF) and radiofrequency radiation (RFR) can have the devastating biological effects of disrupting homeostasis and desynchronizing normal biological rhythms that maintain health. Non-linear, weak field biological oscillations govern body electrophysiology, organize cell and tissue functions and maintain organ systems. Artificial bioelectrical interference can give false information (disruptive signaling) sufficient to affect critical pacemaker cells (of the heart, gut and brain) and desynchronize functions of these important cells that orchestrate function and maintain health. Chronic physiological stress undermines homeostasis whether it is chemically induced or electromagnetically induced (or both exposures are simultaneous contributors). This can eventually break down adaptive biological responses critical to health

  9. Network-based discovery through mechanistic systems biology. Implications for applications--SMEs and drug discovery: where the action is.

    PubMed

    Benson, Neil

    2015-08-01

    Phase II attrition remains the most important challenge for drug discovery. Tackling the problem requires improved understanding of the complexity of disease biology. Systems biology approaches to this problem can, in principle, deliver this. This article reviews the reports of the application of mechanistic systems models to drug discovery questions and discusses the added value. Although we are on the journey to the virtual human, the length, path and rate of learning from this remain an open question. Success will be dependent on the will to invest and make the most of the insight generated along the way.

  10. Biological nitrogen fixation by alternative nitrogenases in boreal cyanolichens: importance of molybdenum availability and implications for current biological nitrogen fixation estimates.

    PubMed

    Darnajoux, Romain; Zhang, Xinning; McRose, Darcy L; Miadlikowska, Jolanta; Lutzoni, François; Kraepiel, Anne M L; Bellenger, Jean-Philippe

    2017-01-01

    Cryptogamic species and their associated cyanobacteria have attracted the attention of biogeochemists because of their critical roles in the nitrogen cycle through symbiotic and asymbiotic biological fixation of nitrogen (BNF). BNF is mediated by the nitrogenase enzyme, which, in its most common form, requires molybdenum at its active site. Molybdenum has been reported as a limiting nutrient for BNF in many ecosystems, including tropical and temperate forests. Recent studies have suggested that alternative nitrogenases, which use vanadium or iron in place of molybdenum at their active site, might play a more prominent role in natural ecosystems than previously recognized. Here, we studied the occurrence of vanadium, the role of molybdenum availability on vanadium acquisition and the contribution of alternative nitrogenases to BNF in the ubiquitous cyanolichen Peltigera aphthosa s.l. We confirmed the use of the alternative vanadium-based nitrogenase in the Nostoc cyanobiont of these lichens and its substantial contribution to BNF in this organism. We also showed that the acquisition of vanadium is strongly regulated by the abundance of molybdenum. These findings show that alternative nitrogenase can no longer be neglected in natural ecosystems, particularly in molybdenum-limited habitats.

  11. Evaluation of the biological differences of canine and human factor VIII in gene delivery: Implications in human hemophilia treatment

    USDA-ARS?s Scientific Manuscript database

    The canine is the most important large animal model for testing novel hemophilia A(HA) treatment. It is often necessary to use canine factor VIII (cFIII) gene or protein for the evaluation of HA treatment in the canine model. However, the different biological properties between cFVIII and human FVII...

  12. Hg2+ interference with the structure of tobacco etch virus protease (TEVp) and its implications for biological engineering

    NASA Astrophysics Data System (ADS)

    Wang, Jing-Zhang; Ren, Si-Yan; Zhu, Guo-Fei; Xi, Lei; Han, Yong-Guang; Luo, Yue; Du, Lin-Fang

    2013-11-01

    Tobacco etch virus protease (TEVp) has specific and highly-conserved enzymatic activity, and is frequently applied in the fields of biology and biotechnology. Hg2+ can be utilized to purify target proteins in metal-chelate affinity chromatography. However, because Hg2+ has special biological toxity, it may endanger the stability of TEVp and hinder the utilization of TEVp in the related research. We determined the effects of Hg2+ on the structure of TEVp by means of intrinsic fluorescence, synchronous fluorescence, Fourier transform infrared (FTIR), and circular dichroism (CD) spectroscopies. The fluorescence emission and the synchronous fluorescence spectra suggested that Hg2+ induced the increased hydrophobicity around both of the tryptophan and the tyrosine residues in TEVp. Hg2+ mainly quenched the fluorescence of TEVp in a static process, with the possible formation of a complex (approximate molar ratio of 1:1), and the electrostatic force was the main binding force between TEVp and Hg2+. The FTIR and CD spectra suggested that Hg2+ induced the increased content of β-sheet in TEVp, indicating that Hg2+ may bind to the catalytic residues His46 and Cys151 in TEVp and promote TEVp to form a more compact structure. The Hg2+-induced structural changes of TEVp may potentially inhibit the catalytic activity of TEVp. These findings are beneficial for the intensive understanding of the factors that influence the stability of TEVp, and are helpful for the efficient and effective application of TEVp in the fields of biology and biological engineering.

  13. Cooperative and Active Learning in Undergraduate Biological Laboratories at FIU--Implications to TA Teaching and Training

    ERIC Educational Resources Information Center

    Penwell, Rebecca A.; Elsawa, Sherine F.; Pitzer, Thomas

    2004-01-01

    There were several changes in the laboratory teaching program in the Biological Sciences at Florida International University (FIU) between 1993-1994. The underlying goal was the improvement of the amount of material learned and retained by the student, but these changes showed little positive improvement. It was deemed necessary for FIU to…

  14. Papers presented to the Conference on Large Body Impacts and Terrestrial Evolution: Geological, Climatological, and Biological Implications

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The effects of large impacts on the environment are discussed and include thermal effects, atmospheric effects, changes in ocean temperatures, and geomagnetic anomalies. Biological factors such as extinction and increases in mutation development were investigated. Geological anomalies studied include stratigraphic gaps, extinction of entire boundary layers from the geological record, and geochemical oddities. Evidence was examined for impact cratering throughout the world.

  15. Non-Western Students' Causal Reasoning about Biologically Adaptive Changes in Humans, Other Animals and Plants: Instructional and Curricular Implications

    ERIC Educational Resources Information Center

    Mbajiorgu, Ngozika; Anidu, Innocent

    2017-01-01

    Senior secondary school students (N = 360), 14- to 18-year-olds, from the Igbo culture of eastern Nigeria responded to a questionnaire requiring them to give causal explanations of biologically adaptive changes in humans, other animals and plants. A student subsample (n = 36) was, subsequently, selected for in-depth interviews. Significant…

  16. Positionings of Racial, Ethnic, and Linguistic Minority Students in High School Biology Class: Implications for Science Education in Diverse Classrooms

    ERIC Educational Resources Information Center

    Ryu, Minjung

    2015-01-01

    In the present study, I analyze ethnographic data from a year-long study of two Advanced Placement (AP) Biology classes that enrolled students with diverse racial, ethnic, and linguistic backgrounds. Specifically, I consider participation, positioning, and learning of newcomer Korean students in the focal classes. Building on the notion of figured…

  17. Positionings of Racial, Ethnic, and Linguistic Minority Students in High School Biology Class: Implications for Science Education in Diverse Classrooms

    ERIC Educational Resources Information Center

    Ryu, Minjung

    2015-01-01

    In the present study, I analyze ethnographic data from a year-long study of two Advanced Placement (AP) Biology classes that enrolled students with diverse racial, ethnic, and linguistic backgrounds. Specifically, I consider participation, positioning, and learning of newcomer Korean students in the focal classes. Building on the notion of figured…

  18. Invasive Blackberry Species in Oregon, USA: Their Identity and Susceptibility to Rust Disease, and Implications for Biological Control

    USDA-ARS?s Scientific Manuscript database

    Two of five species of European blackberry (Rubus fruticosus L. Aggregate) along the West Coast of the United States are invasive, and they are also similar in appearance. Biological control by Phragmidium violaceum, causal agent of a rust disease, was under consideration when rust-diseased blackber...

  19. Structural and functional diversity among amyloid proteins: Agents of disease, building blocks of biology, and implications for molecular engineering.

    PubMed

    Bleem, Alissa; Daggett, Valerie

    2017-01-01

    Amyloids have long been associated with protein dysfunction and neurodegenerative diseases, but recent research has demonstrated that some organisms utilize the unique properties of the amyloid fold to create functional structures with important roles in biological processes. Additionally, new engineering approaches have taken advantage of amyloid structures for implementation in a wide variety of materials and devices. In this review, the role of amyloid in human disease is discussed and compared to the functional amyloids, which serve a largely structural purpose. We then consider the use of amyloid constructs in engineering applications, including their utility as building blocks for synthetic biology and molecular engineering. Biotechnol. Bioeng. 2017;114: 7-20. © 2016 Wiley Periodicals, Inc.

  20. Evidence for two-dimensional solitary sound waves in a lipid controlled interface and its implications for biological signalling

    PubMed Central

    Shrivastava, Shamit; Schneider, Matthias F.

    2014-01-01

    Biological membranes by virtue of their elastic properties should be capable of propagating localized perturbations analogous to sound waves. However, the existence and the possible role of such waves in communication in biology remain unexplored. Here, we report the first observations of two-dimensional solitary elastic pulses in lipid interfaces, excited mechanically and detected by FRET. We demonstrate that the nonlinearity near a maximum in the susceptibility of the lipid monolayer results in solitary pulses that also have a threshold for excitation. These experiments clearly demonstrate that the state of the interface regulates the propagation of pulses both qualitatively and quantitatively. Finally, we elaborate on the striking similarity of the observed phenomenon to nerve pulse propagation and a thermodynamic basis of cell signalling in general. PMID:24942845

  1. Evidence for two-dimensional solitary sound waves in a lipid controlled interface and its implications for biological signalling.

    PubMed

    Shrivastava, Shamit; Schneider, Matthias F

    2014-08-06

    Biological membranes by virtue of their elastic properties should be capable of propagating localized perturbations analogous to sound waves. However, the existence and the possible role of such waves in communication in biology remain unexplored. Here, we report the first observations of two-dimensional solitary elastic pulses in lipid interfaces, excited mechanically and detected by FRET. We demonstrate that the nonlinearity near a maximum in the susceptibility of the lipid monolayer results in solitary pulses that also have a threshold for excitation. These experiments clearly demonstrate that the state of the interface regulates the propagation of pulses both qualitatively and quantitatively. Finally, we elaborate on the striking similarity of the observed phenomenon to nerve pulse propagation and a thermodynamic basis of cell signalling in general.

  2. The leafminer Liriomyza trifolii (Diptera: Agromyzidae) encapsulates its koinobiont parasitoid Halticoptera circulus (Hymenoptera: Pteromalidae): implications for biological control.

    PubMed

    Kemmochi, T; Fujimori, S; Saito, T

    2016-06-01

    The koinobiont parasitoid Halticoptera circulus (Walker) is a potential biological control agent of leafminers, but it has only rarely been collected from the invasive leafminer, Liriomyza trifolii (Burgess), in Japan. To understand why this is the case, parasitism and development of H. circulus in L. trifolii was compared with parasitism and development in two indigenous leafminer species, Liriomyza chinensis Kato and Chromatomyia horticola (Goureau). There was no significant difference in parasitism rates by H. circulus in the three leafminer species and the eggs and larvae successfully developed in L. chinensis and C. horticola. However, H. circulus failed to develop in L. trifolii, where developmental stages were encapsulated by host haemocytes. This parasitoid may be a good agent to control indigenous leafminers such as L. chinensis and C. horticola but is unlikely to be useful for the biological control of the invasive L. trifolii in Japan.

  3. Clinical implications of basic science discoveries: janus resurrected--two faces of B cell and plasma cell biology.

    PubMed

    Woodle, E S; Rothstein, D M

    2015-01-01

    B cells play a complex role in the immune response. In addition to giving rise to plasma cells (PCs) and promoting T cell responses via antigen presentation, they perform immunoregulatory functions. This knowledge has created concerns regarding nonspecific B cell depletional therapy because of the potential to paradoxically augment immune responses. Recent studies now indicate that PCs have immune functions beyond immunoglobulin synthesis. Evidence for a new role for PCs as potent regulatory cells (via IL-10 and IL-35 production) is discussed including the implications for PC-targeted therapies currently being developed for clinical transplantation.

  4. Hofmeister effects in biology: effect of choline addition on the salt-induced super activity of horseradish peroxidase and its implication for salt resistance of plants.

    PubMed

    Pinna, M C; Bauduin, P; Touraud, D; Monduzzi, M; Ninham, B W; Kunz, W

    2005-09-01

    The effect of choline addition on the salt-induced super activity of horseradish peroxidase (HRP) is investigated. HRP is presented in the literature as an efficient H(2)O(2) scavenger, and choline is the precursor of glycine betaine, a strong osmoprotectant molecule. Both the regulations of H(2)O(2) and of osmoprotectant concentrations are implicated in plants in order to counteract salt-induced cell damage. For the oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), sulfate anions were found to play a crucial role in the increase of HRP activity. This induced super activity can be strongly reduced by adding choline chloride. The phenomena provide an example of physicochemical Hofmeister effects playing a central regulatory role in an important biological system.

  5. Population dynamics of the white wax scale, Ceroplastes destructor (Hemiptera: Coccidae), on citrus in South Africa, with implications for biological control.

    PubMed

    Wakgari, W M; Giliomee, J H

    2001-08-01

    The population dynamics of the white wax scale, Ceroplastes destructor Newstead, was studied intensively in four easy-peel citrus orchards in the Western Cape Province of South Africa over three consecutive years (1997-1999). Key factor analysis was used to determine and quantify the contribution of individual mortality factors to the total generation mortality. Key stage mortality, determined from a cohort life table, was in the third instar and pre-ovipositing female stages. Mortality of C. destructor was caused primarily by parasitoids, predators and miscellaneous factors. Parasitoids and miscellaneous factors acted as density-dependent regulatory agents during the pre-ovipositional and first instar stages respectively. This has implications for biological control of C. destructor. Some of the mortality factors acted either randomly with no reference to the population densities or in an inverse density-dependent manner during the egg-crawler, second or third instar stages.

  6. Evidence for biological activity in mineralization of secondary sulphate deposits in a basaltic environment: implications for the search for life in the Martian subsurface

    SciTech Connect

    C. Doc Richardson; Nancy W. Hinman; Jill R. Scott

    2013-10-01

    Evidence of microbial activity associated with mineralization of secondary Na-sulphate minerals (thenardite, mirabilite) in the basaltic subsurface of Craters of the Moon National Monument (COM), Idaho were examined by scanning electron microscopy, X-ray diffraction, laser desorption Fourier transform ion cyclotron resonance mass spectrometry (LD-FTICR-MS), Fourier transform infrared spectroscopy (FTIR) and isotope ratio mass spectrometry. Peaks suggestive of bio/organic compounds were observed in the secondary Na-sulphate deposits by LD-FTICR-MS. FTIR provided additional evidence for the presence of bio/organic compounds. Sulphur fractionation was explored to assist in determining if microbes may play a role in oxidizing sulphur. The presence of bio/organic compounds associated with Na-sulphate deposits, along with the necessity of oxidizing reduced sulphur to sulphate, suggests that biological activity may be involved in the formation of these secondary minerals. The secondary Na-sulphate minerals probably form from the overlying basalt through leached sodium ions and sulphate ions produced by bio-oxidation of Fe-sulphide minerals. Since the COM basalts are one of the most comparable terrestrial analogues for their Martian counterparts, the occurrence of biological activity in the formation of sulphate minerals at COM has direct implications for the search for life on Mars. In addition, the presence of caves on Mars suggests the importance of these environments as possible locations for growth and preservation of microbial activity. Therefore, understanding the physiochemical pathways of abiotic and biotic mineralization in the COM subsurface and similar basaltic settings has direct implications for the search for extinct or extant life on Mars.

  7. Impact of graphic format on perception of change in biological data: implications for health monitoring in conditions such as asthma.

    PubMed

    Jansen, Jesse; McCaffery, Kirsten J; Hayen, Andrew; Ma, David; Reddel, Helen K

    2012-03-01

    Variation in graphic format can substantially influence interpretation of data. Despite a large body of literature on the optimal design of graphs, little attention has been paid to the format of charts for health monitoring. This study assessed the effect of aspect ratio (x:y ratio) and interconnecting lines on visual identification of change in biological data, such as during asthma exacerbations. Eighty volunteers viewed 72 sets of six consecutive blocks of unidentified biological data, recording if each block of data was increasing, decreasing, or the same as the previous block. Three chart aspect ratios were examined (A, 5.2:1; B, 3.0:1; C, 1.1:1), with or without lines between data points. Datasets from lung function monitoring by asthma patients included a mild/moderate/severe fall ('exacerbation') or no exacerbation. False negative (missing true exacerbations) and false positive (identifying non-existent exacerbations) responses were calculated. 84% of exacerbation blocks were correctly identified. There was a significant interaction between exacerbation severity and aspect ratio (p=0.0048). The most compressed chart (C) had the fewest false negative responses. Moderate falls were missed in 24%, 12%, and 5% of trials on charts A, B, and C, respectively (C vs A: adjusted relative risk 0.19 (95% CI 0.12 to 0.30)). False positive responses were infrequent (A, 2.5%; B, 3.8%; C, 8.3%), increasing slightly if data points were joined with lines (4.3% vs 5.1%, p=0.004) . Compressed charts can improve the visual detection of change in biological data by up to 80%. The aspect ratio of charts should be standardised to facilitate clinical pattern recognition.

  8. THE BIOLOGIC BASIS OF TRANSGENDER IDENTITY: 2D:4D FINGER LENGTH RATIOS IMPLICATE A ROLE FOR PRENATAL ANDROGEN ACTIVITY.

    PubMed

    Leinung, Matthew; Wu, Christina

    2017-06-01

    The biologic basis for gender identity is unknown. Research has shown that the ratio of the length of the second and fourth digits (2D:4D) in mammals is influenced by biologic sex in utero, but data on 2D:4D ratios in transgender individuals are scarce and contradictory. We investigated a possible association between 2D:4D ratio and gender identity in our transgender clinic population in Albany, New York. We prospectively recruited 118 transgender subjects undergoing hormonal therapy (50 female to male [FTM] and 68 male to female [MTF]) for finger length measurement. The control group consisted of 37 cisgender volunteers (18 females, 19 males). The length of the second and fourth digits were measured using digital calipers. The 2D:4D ratios were calculated and analyzed with unpaired t tests. FTM subjects had a smaller dominant hand 2D:4D ratio (0.983 ± 0.027) compared to cisgender female controls (0.998 ± 0.021, P = .029), but a ratio similar to control males (0.972 ± 0.036, P =.19). There was no difference in the 2D:4D ratio of MTF subjects (0.978 ± 0.029) compared to cisgender male controls (0.972 ± 0.036, P = .434). Our findings are consistent with a biologic basis for transgender identity and the possibilities that FTM gender identity is affected by prenatal androgen activity but that MTF transgender identity has a different basis. 2D:4D = 2nd digit to 4th digit; FTM = female to male; MTF = male to female.

  9. Are Internet use and video-game-playing addictive behaviors? Biological, clinical and public health implications for youths and adults

    PubMed Central

    Yau, Yvonne H. C.; Crowley, Michael J.; Mayes, Linda C.; Potenza, Marc N.

    2013-01-01

    Internet use and video-game playing are experiencing rapid growth among both youth and adult populations. Research suggests that a minority of users experience symptoms traditionally associated with substance-related addictions. Mental health professionals, policy makers and the general public continue to debate the issue of Internet addiction (IA) and problematic video-game playing (PVG). This review identifies existing studies into the clinical and biological characteristics of these disorders that may help guide decisions as to whether or not IA and PVG should be grouped together with substance use disorders (SUDs). PMID:24288435

  10. Population synchronies within and between ocean basins: Apparent teleconnections and implications as to physical-biological linkage mechanisms

    NASA Astrophysics Data System (ADS)

    Alheit, Jürgen; Bakun, Andrew

    2010-02-01

    Major fish populations in large marine ecosystems separated by thousands of kilometres often seem to fluctuate in decadal-scale synchrony indicating strong forcing of ecosystem processes and population dynamics by regional and global climatic variability. The climate signals propagating through the atmosphere appear to act as synchronizing agents leading to teleconnection patterns between distant marine ecosystems and populations. This review is an attempt (i) to summarize these apparent within and between ocean basin teleconnection patterns in a comparative framework using particularly suggestive examples and (ii) to unravel physical-biological linkage mechanisms between a climate signal and fish populations. Synchronies in the timing of physical and biological processes between the Kuroshio and the Humboldt Current ecosystems are particularly striking. The collapse of the Peruvian anchovy in 1971 and the rapid decrease of the Japanese anchovy seem not to be directly associated with climate indices such as the Southern Oscillation Index (SOI) and the Pacific Decadal Oscillation (PDO). The "climate regime shift" in the mid-1970s in the North Pacific indicated by the PDO is not reflected in the dynamics of anchovies and sardines and other main components in both ecosystems, whereas the Asian Winter Monsoon Index (MOI) and the Arctic Oscillation (AO) seem to correlate with these events, at least in the Northwest Pacific. We speculate that the synchrony between processes in the Kuroshio and Humboldt systems is brought about by changes in the basin-scale coupled ocean-atmosphere circulation in North and South Pacific basins. The example of European aquatic systems describes physical-biological synchronies for which the NAO appears to be the synchronizing agent. When the NAO index changed in the late 1980s from a negative to a positive phase, a coherent increase in water temperature was observed in the Central Baltic, the North Sea, the NW Mediterranean and north and

  11. Are Internet use and video-game-playing addictive behaviors? Biological, clinical and public health implications for youths and adults.

    PubMed

    Yau, Yvonne H C; Crowley, Michael J; Mayes, Linda C; Potenza, Marc N

    2012-09-01

    Internet use and video-game playing are experiencing rapid growth among both youth and adult populations. Research suggests that a minority of users experience symptoms traditionally associated with substance-related addictions. Mental health professionals, policy makers and the general public continue to debate the issue of Internet addiction (IA) and problematic video-game playing (PVG). This review identifies existing studies into the clinical and biological characteristics of these disorders that may help guide decisions as to whether or not IA and PVG should be grouped together with substance use disorders (SUDs).

  12. Organization, integration, and assembly of genetic and epigenetic regulatory machinery in nuclear microenvironments: implications for biological control in cancer.

    PubMed

    Stein, Gary S; Zaidi, Sayyed K; Stein, Janet L; Lian, Jane B; van Wijnen, Andre J; Montecino, Martin; Young, Daniel W; Javed, Amjad; Pratap, Jitesh; Choi, Je-Yong; Ali, Syed A; Pande, Sandhya; Hassan, Mohammad Q

    2009-02-01

    There is growing awareness that the fidelity of gene expression necessitates coordination of transcription factor metabolism and organization of genes and regulatory proteins within the three-dimensional context of nuclear architecture. The regulatory machinery that governs genetic and epigenetic control of gene expression is compartmentalized in nuclear microenvironments. Temporal and spatial parameters of regulatory complex organization and assembly are functionally linked to biological control and are compromised with the onset and progression of tumorigenesis. High throughput imaging of cells, tissues, and tumors, including live cell analysis, is expanding research's capabilities toward translating components of nuclear organization into novel strategies for cancer diagnosis and therapy.

  13. Bio-ISRU Concepts using microorganisms to release O2 and H2 on Moon and Mars

    NASA Astrophysics Data System (ADS)

    Slenzka, Klaus; Kempf, Juergen

    life support system embedded in a permanent Moon or Mars base. This method demonstrates a low energetic oxygen release, a serious alternative to high the energetic oxygen separation of the ilmenite process, fluorination process, melting hydrol-ysis, vacuum distillation or photo dissociation, respectively. Not only oxygen production of the biological processes should be in focus of space application. Also the metal oxide reducing component of the process might run batteries to provide energy to devices of a Moon or Mars base.

  14. Warming and increased precipitation frequency on the Colorado Plateau: implications for biological soil crusts and soil processes

    SciTech Connect

    Zelikova, Tamara J.; Housman, David C.; Grote, Ed E.; Neher, Deborah A.; Belnap, Jayne

    2012-01-20

    Changes in temperature and precipitation are expected to influence ecosystem processes worldwide. Despite their globally large extent, few studies to date have examined the effects of climate change in desert ecosystems, where biological soil crusts are key nutrient cycling components. The goal of this work was to assess how increased temperature and frequency of summertime precipitation affect the contributions of crust organisms to soil processes. With a combination of experimental 2°C warming and altered summer precipitation frequency applied over 2 years, we measured soil nutrient cycling and the structure and function of crust communities. We saw no change in crust cover, composition, or other measures of crust function in response to 2°C warming and no effects on any measure of soil chemistry. In contrast, crust cover and function responded to increased frequency of summer precipitation, shifting from moss to cyanobacteria-dominated crusts; however, in the short timeframe we measured, there was no accompanying change in soil chemistry. Total bacterial and fungal biomass was also reduced in watered plots, while the activity of two enzymes increased, indicating a functional change in the microbial community. Taken together, our results highlight the limited effects of warming alone on biological soil crust communities and soil chemistry, but demonstrate the substantially larger effects of altered summertime precipitation.

  15. Dynamics of Introduced Populations of Phragmidium violaceum and Implications for Biological Control of European Blackberry in Australia▿

    PubMed Central

    Gomez, D. R.; Evans, K. J.; Baker, J.; Harvey, P. R.; Scott, E. S.

    2008-01-01

    Phragmidium violaceum causes leaf rust on the European blackberry (Rubus fruticosus L. aggregate). Multiple strains of this pathogen have been introduced into southern Australia for the biological control of at least 15 taxa of European blackberry, a nonindigenous, invasive plant. In climates conducive to leaf rust, the intensity of disease varies within and among infestations of the genetically variable host. Genetic markers developed from the selective amplification of microsatellite polymorphic loci were used to assess the population genetic structure and reproductive biology of P. violaceum within and among four geographically isolated and diseased infestations of the European blackberry in Victoria, Australia. Despite the potential for long-distance aerial dispersal of urediniospores, there was significant genetic differentiation among all populations, which was not associated with geographic separation. An assessment of multilocus linkage disequilibrium revealed temporal and geographic variation in the occurrence of random mating among the four populations. The presence of sexual spore states and the results of genetic analyses indicated that recombination, and potentially random migration and genetic drift, played an important role in maintaining genotypic variation within populations. Recombination and genetic differentiation in P. violaceum, as well as the potential for metapopulation structure, suggest the need to release additional, genetically diverse strains of the biocontrol agent at numerous sites across the distribution of the Australian blackberry infestation for maximum establishment and persistence. PMID:18641150

  16. Robotic Subsurface Analyzer and Sample Handler for Resource Reconnaissance and Preliminary Site Assessment for ISRU Activities at the Lunar Cold Traps

    NASA Technical Reports Server (NTRS)

    Gorevan, S. P.; Wilson, J.; Bartlett, P.; Powderly, J.; Lawrence, D.; Elphic, R.; Mungas, G.; McCullough, E.; Stoker, C.; Cannon, H.

    2004-01-01

    Since the 1960s, claims have been made that water ice deposits should exist in permanently shadowed craters near both lunar poles. Recent interpretations of data from the Lunar Prospector-Neutron Spectrometer (LP- NS) confirm that significant concentrations of hydrogen exist, probably in the form of water ice, in the permanently shadowed polar cold traps. Yet, due to the large spatial resolution (45-60 Ian) of the LP-NS measurements relative to these shadowed craters (approx.5-25 km), these data offer little certainty regarding the precise location, form or distribution of these deposits. Even less is known about how such deposits of water ice might effect lunar regolith physical properties relevant to mining, excavation, water extraction and construction. These uncertainties will need to be addressed in order to validate fundamental lunar In Situ Resource Utilization (ISRU) precepts by 2011. Given the importance of the in situ utilization of water and other resources to the future of space exploration a need arises for the advanced deployment of a robotic and reconfigurable system for physical properties and resource reconnaissance. Based on a collection of high-TRL. designs, the Subsurface Analyzer and Sample Handler (SASH) addresses these needs, particularly determining the location and form of water ice and the physical properties of regolith. SASH would be capable of: (1) subsurface access via drilling, on the order of 3-10 meters into both competent targets (ice, rock) and regolith, (2) down-hole analysis through drill string embedded instrumentation and sensors (Neutron Spectrometer and Microscopic Imager), enabling water ice identification and physical properties measurements; (3) core and unconsolidated sample acquisition from rock and regolith; (4) sample handling and processing, with minimized contamination, sample containerization and delivery to a modular instrument payload. This system would be designed with three mission enabling goals, including: (1

  17. Robotic Subsurface Analyzer and Sample Handler for Resource Reconnaissance and Preliminary Site Assessment for ISRU Activities at the Lunar Cold Traps

    NASA Technical Reports Server (NTRS)

    Gorevan, S. P.; Wilson, J.; Bartlett, P.; Powderly, J.; Lawrence, D.; Elphic, R.; Mungas, G.; McCullough, E.; Stoker, C.; Cannon, H.

    2004-01-01

    Since the 1960s, claims have been made that water ice deposits should exist in permanently shadowed craters near both lunar poles. Recent interpretations of data from the Lunar Prospector-Neutron Spectrometer (LP- NS) confirm that significant concentrations of hydrogen exist, probably in the form of water ice, in the permanently shadowed polar cold traps. Yet, due to the large spatial resolution (45-60 Ian) of the LP-NS measurements relative to these shadowed craters (approx.5-25 km), these data offer little certainty regarding the precise location, form or distribution of these deposits. Even less is known about how such deposits of water ice might effect lunar regolith physical properties relevant to mining, excavation, water extraction and construction. These uncertainties will need to be addressed in order to validate fundamental lunar In Situ Resource Utilization (ISRU) precepts by 2011. Given the importance of the in situ utilization of water and other resources to the future of space exploration a need arises for the advanced deployment of a robotic and reconfigurable system for physical properties and resource reconnaissance. Based on a collection of high-TRL. designs, the Subsurface Analyzer and Sample Handler (SASH) addresses these needs, particularly determining the location and form of water ice and the physical properties of regolith. SASH would be capable of: (1) subsurface access via drilling, on the order of 3-10 meters into both competent targets (ice, rock) and regolith, (2) down-hole analysis through drill string embedded instrumentation and sensors (Neutron Spectrometer and Microscopic Imager), enabling water ice identification and physical properties measurements; (3) core and unconsolidated sample acquisition from rock and regolith; (4) sample handling and processing, with minimized contamination, sample containerization and delivery to a modular instrument payload. This system would be designed with three mission enabling goals, including: (1

  18. Changing tides for Lake Erie: the biogeochemical evolution of a Laurentian Great Lake and implications for biological communities of the future (Invited)

    NASA Astrophysics Data System (ADS)

    Wilhelm, S.; Steffen, M.; Belisle, B. S.; Dearth, S.; Campbell, M.; Boyer, G. L.; Watson, S.; Bourbonniere, R. A.; DeBruyn, J.; Campagna, S.

    2013-12-01

    Lake Erie is perhaps the most anthropogenically influenced of all the Laurentian Great Lakes. The history of the lake clearly demonstrates one where external loads of phosphorous drove primary production to a point where the lake was declared dead in the 1970's. The lake however, is also one of the greatest environmental success stories, as abatement programs had seen this system begin to return to health until the mid-1990's. In recent years, however, new cyanobacterial blooms of the potentially toxic cyanobacterium Microcystis have dominated the water column in late-summer months. Driven by a combination of changes in water column chemistry and regional climate, Lake Erie is no longer predictably P-limited through summer months and in some cases experiments have clearly shown that within the lake primary productivity is now N-limited. Experimentally, our goal has been to couple water column geochemistry with biomolecular pathways in cells to have the biology tell us which elements are driving community structure and function. Using community level transcriptomics and metabolomics, our observations suggest that changes in the chemical species of nitrogen, and especially the presence of urea, may be controlling the biological community structure of microbial communities in Lake Erie and may in part shape the extent of toxic cyanobacterial blooms. Moreover, data from multiple sampling surveys now demonstrates that additives designed to shape nutrient use in terrestrial environments may be influencing nitrogen cycles within the lake. Coupled to historical data sets dating back decades, we will discuss how seemingly minor alterations in system geochemistry over time have major biological implications for regional stakeholders. MODIS image of Lake Erie algal bloom in 2012

  19. Systems biology and genome-wide approaches to unveil the molecular players involved in the pre-germinative metabolism: implications on seed technology traits.

    PubMed

    Macovei, Anca; Pagano, Andrea; Leonetti, Paola; Carbonera, Daniela; Balestrazzi, Alma; Araújo, Susana S

    2016-10-11

    The pre-germinative metabolism is among the most fascinating aspects of seed biology. The early seed germination phase, or pre-germination, is characterized by rapid water uptake (imbibition), which directs a series of dynamic biochemical events. Among those are enzyme activation, DNA damage and repair, and use of reserve storage compounds, such as lipids, carbohydrates and proteins. Industrial seedling production and intensive agricultural production systems require seed stocks with high rate of synchronized germination and low dormancy. Consequently, seed dormancy, a quantitative trait related to the activation of the pre-germinative metabolism, is probably the most studied seed trait in model species and crops. Single omics, systems biology, QTLs and GWAS mapping approaches have unveiled a list of molecules and regulatory mechanisms acting at transcriptional, post-transcriptional and post-translational levels. Most of the identified candidate genes encode for regulatory proteins targeting ROS, phytohormone and primary metabolisms, corroborating the data obtained from simple molecular biology approaches. Emerging evidences show that epigenetic regulation plays a crucial role in the regulation of these mentioned processes, constituting a still unexploited strategy to modulate seed traits. The present review will provide an up-date of the current knowledge on seed pre-germinative metabolism, gathering the most relevant results from physiological, genetics, and omics studies conducted in model and crop plants. The effects exerted by the biotic and abiotic stresses and priming are also addressed. The possible implications derived from the modulation of pre-germinative metabolism will be discussed from the point of view of seed quality and technology.

  20. Biological effects and subsequent economic effects and losses from marine pollution and degradations in marine environments: Implications from the literature.

    PubMed

    Ofiara, Douglas D; Seneca, Joseph J

    2006-08-01

    This paper serves as the missing piece in a more fuller understanding about economic losses from marine pollution, and demonstrates what losses have been estimated in the literature. Biological effects from marine pollution are linked with resulting economic effects and losses. The merging of these two areas is usually absent in studies of marine pollution losses. The literature has examined several effects due to marine pollution: damages due to harvest closures-restrictions, damages from consumption of unsafe seafood, damages due to decreased recreational activity, and damages related to waterfront real estate adjacent to contaminated water. Overall, marine pollution can and has resulted in sizable economic effects and losses. On the basis of the literature there is adequate justification for public policy actions to curb marine pollution, require inspection of seafood for toxic substances, and preserve marine water quality and sensitive marine environments.

  1. Redefining Relative Biological Effectiveness in the Context of the EQDX Formalism: Implications for Alpha-Particle Emitter Therapy.

    PubMed

    Hobbs, Robert F; Howell, Roger W; Song, Hong; Baechler, Sébastien; Sgouros, George

    2013-12-30

    Alpha-particle radiopharmaceutical therapy (αRPT) is currently enjoying increasing attention as a viable alternative to chemotherapy for targeting of disseminated micrometastatic disease. In theory, αRPT can be personalized through pre-therapeutic imaging and dosimetry. However, in practice, given the particularities of α-particle emissions, a dosimetric methodology that accurately predicts the thresholds for organ toxicity has not been reported. This is in part due to the fact that the biological effects caused by α-particle radiation differ markedly from the effects caused by traditional external beam (photon or electron) radiation or β-particle emitting radiopharmaceuticals. The concept of relative biological effectiveness (RBE) is used to quantify the ratio of absorbed doses required to achieve a given biological response with alpha particles versus a reference radiation (typically a beta emitter or external beam radiation). However, as conventionally defined, the RBE varies as a function of absorbed dose and therefore a single RBE value is limited in its utility because it cannot be used to predict response over a wide range of absorbed doses. Therefore, efforts are underway to standardize bioeffect modeling for different fractionation schemes and dose rates for both nuclear medicine and external beam radiotherapy. Given the preponderant use of external beams of radiation compared to nuclear medicine in cancer therapy, the more clinically relevant quantity, the 2 Gy equieffective dose, EQD2(α/β), has recently been proposed by the ICRU. In concert with EQD2(α/β), we introduce a new, redefined RBE quantity, named RBE2(α/β), as the ratio of the two linear coefficients that characterize the α particle absorbed dose-response curve and the low-LET megavoltage photon 2 Gy fraction equieffective dose-response curve. The theoretical framework for the proposed new formalism is presented along with its application to experimental data obtained from

  2. Redefining relative biological effectiveness in the context of the EQDX formalism: implications for alpha-particle emitter therapy.

    PubMed

    Hobbs, Robert F; Howell, Roger W; Song, Hong; Baechler, Sébastien; Sgouros, George

    2014-01-01

    Alpha-particle radiopharmaceutical therapy (αRPT) is currently enjoying increasing attention as a viable alternative to chemotherapy for targeting of disseminated micrometastatic disease. In theory, αRPT can be personalized through pre-therapeutic imaging and dosimetry. However, in practice, given the particularities of α-particle emissions, a dosimetric methodology that accurately predicts the thresholds for organ toxicity has not been reported. This is in part due to the fact that the biological effects caused by α-particle radiation differ markedly from the effects caused by traditional external beam (photon or electron) radiation or β-particle emitting radiopharmaceuticals. The concept of relative biological effectiveness (RBE) is used to quantify the ratio of absorbed doses required to achieve a given biological response with alpha particles versus a reference radiation (typically a beta emitter or external beam radiation). However, as conventionally defined, the RBE varies as a function of absorbed dose and therefore a single RBE value is limited in its utility because it cannot be used to predict response over a wide range of absorbed doses. Therefore, efforts are underway to standardize bioeffect modeling for different fractionation schemes and dose rates for both nuclear medicine and external beam radiotherapy. Given the preponderant use of external beams of radiation compared to nuclear medicine in cancer therapy, the more clinically relevant quantity, the 2 Gy equieffective dose, EQD2(α/β), has recently been proposed by the ICRU. In concert with EQD2(α/β), we introduce a new, redefined RBE quantity, named RBE2(α/β), as the ratio of the two linear coefficients that characterize the α particle absorbed dose-response curve and the low-LET megavoltage photon 2 Gy fraction equieffective dose-response curve. The theoretical framework for the proposed new formalism is presented along with its application to experimental data obtained from

  3. Implication of possible therapies targeted for the tachykinergic system with the biology of neurokinin receptors and emerging related proteins.

    PubMed

    Rameshwar, Pranela

    2007-01-01

    The neurokinin (NK) receptor family has been proposed as targets for neural-related diseases. The experimental studies indicate that this family of receptors might also be targets for malignancies, both solid and hematological tumors. However, an understanding of the biology of other rmolecules with sequence similarity to NK receptors is required. Of significance is the HGFIN gene that shares structural homology with NK1. Through this homology, the HGFIN interacts with the high affinity ligand of NK1, substance P. This report discusses potential applications for targets against NK receptors, and the role of HGFIN in drug designs. This review is relevant for central and peripheral nervous system drug development, and also cancer drugs for breast and neuroblastoma. The potential for leukemia drugs and Patents are also discussed.

  4. Potential Hybridization between Two Invasive Termite Species, Coptotermes formosanus and C. gestroi (Isoptera: Rhinotermitidae), and Its Biological and Economic Implications.

    PubMed

    Su, Nan-Yao; Chouvenc, Thomas; Li, Hou-Feng

    2017-01-25

    The Asian subterranean termite, Coptotermes gestroi, is a tropical species but has increasingly been collected from the subtropics in recent years, making it sympatric to the Formosan subterranean termite, C. formosanus in at least three areas, Taiwan, Hawaii, and Florida. Simultaneous flights by these two species were observed since 2013 in South Florida, during which interspecies tandems were observed. Laboratory mating of C. formosanus and C. gestroi alates produced hybrid incipient colonies of larger population size. Studies are underway to examine the presence in the field of hybrid colonies in sympatric areas of Taiwan and Florida. Other biological characteristics of C. formosanus × C. gestroi hybrids being studied include temperature tolerance and preference, colony growth rate, wood-consumption rate, and reproductive fertility. This current research aims to determine the potential establishment of a hybrid termite population in south Florida and Taiwan. It investigates the risk of introgressive hybridization in field populations, with an emphasis on its potential ecological, evolutionary, and economic consequences.

  5. Molecular and cell biology of the prototypic arenavirus LCMV: implications for understanding and combating hemorrhagic fever arenaviruses.

    PubMed

    de la Torre, Juan C

    2009-09-01

    Arenaviruses merit interest as experimental model systems to study virus-host interactions and as clinically important human pathogens. Several arenaviruses, chiefly Lassa virus (LASV), cause hemorrhagic fever (HF) in humans. In addition, evidence indicates that the worldwide-distributed prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) is a neglected human pathogen. Moreover, arenaviruses pose a biodefense threat. No licensed arenavirus vaccines are available, and current therapy is limited to the use of ribavirin, which is only partially effective and associated with significant side effects. The development of arenavirus reverse genetics systems has made it possible to manipulate the arenavirus genome, which is contributing to significant progress in understanding arenavirus molecular and cell biology, as well as arenavirus-host interactions underlying arenavirus-induced HF disease in humans. This, in turn, should facilitate the development of novel both vaccines and antiviral drugs to combat the dual threats of naturally occurring and intentionally introduced arenavirus infections.

  6. Antioxidant and pro-oxidant properties of pyrroloquinoline quinone (PQQ): implications for its function in biological systems.

    PubMed

    He, Kai; Nukada, Hitoshi; Urakami, Teiji; Murphy, Michael P

    2003-01-01

    Pyrroloquinoline quinone (PQQ) is a novel redox cofactor recently found in human milk. It has been reported to function as an essential nutrient, antioxidant and redox modulator in cell culture experiments and in animal models of human diseases. As mitochondria are particularly susceptible to oxidative damage we studied the antioxidant properties of PQQ in isolated rat liver mitochondria. PQQ was an effective antioxidant protecting mitochondria against oxidative stress-induced lipid peroxidation, protein carbonyl formation and inactivation of the mitochondrial respiratory chain. In contrast, PQQ caused extensive cell death to cells in culture. This surprising effect was inhibited by catalase, and was shown to be due to the generation of hydrogen peroxide during the autoxidation of PQQ in culture medium. We conclude that the reactivities of PQQ are dependent on its environment and that it can act as an antioxidant or a pro-oxidant in different biological systems.

  7. Redefining Relative Biological Effectiveness in the Context of the EQDX Formalism: Implications for Alpha-Particle Emitter Therapy

    PubMed Central

    Hobbs, Robert F.; Howell, Roger W.; Song, Hong; Baechler, Sébastien; Sgouros, George

    2014-01-01

    Alpha-particle radiopharmaceutical therapy (αRPT) is currently enjoying increasing attention as a viable alternative to chemotherapy for targeting of disseminated micrometastatic disease. In theory, αRPT can be personalized through pre-therapeutic imaging and dosimetry. However, in practice, given the particularities of α-particle emissions, a dosimetric methodology that accurately predicts the thresholds for organ toxicity has not been reported. This is in part due to the fact that the biological effects caused by α-particle radiation differ markedly from the effects caused by traditional external beam (photon or electron) radiation or β-particle emitting radiopharmaceuticals. The concept of relative biological effectiveness (RBE) is used to quantify the ratio of absorbed doses required to achieve a given biological response with alpha particles versus a reference radiation (typically a beta emitter or external beam radiation). However, as conventionally defined, the RBE varies as a function of absorbed dose and therefore a single RBE value is limited in its utility because it cannot be used to predict response over a wide range of absorbed doses. Therefore, efforts are underway to standardize bioeffect modeling for different fractionation schemes and dose rates for both nuclear medicine and external beam radiotherapy. Given the preponderant use of external beams of radiation compared to nuclear medicine in cancer therapy, the more clinically relevant quantity, the 2 Gy equieffective dose, EQD2(α/β), has recently been proposed by the ICRU. In concert with EQD2(α/β), we introduce a new, redefined RBE quantity, named RBE2(α/β), as the ratio of the two linear coefficients that characterize the α particle absorbed dose-response curve and the low-LET megavoltage photon 2 Gy fraction equieffective dose-response curve. The theoretical framework for the proposed new formalism is presented along with its application to experimental data obtained from

  8. Substrate contributions in micro-ATR of thin samples: implications for analysis of cells, tissue and biological fluids.

    PubMed

    Bassan, Paul; Sachdeva, Ashwin; Lee, Joe; Gardner, Peter

    2013-07-21

    Low-e microscope slides are a common substrate for biological samples. Typically they are used for transflection infrared microspectroscopy but increasingly they are also being used for micro-ATR experiments since it is assumed that the FTIR-ATR absorbance spectra of cells and tissue on low-e substrates will not contain any spectral contributions from the substrate materials. This, in part, is due to the expectation that all the infrared light will be reflected at the highly reflective surface. At low sample thicknesses, however (e.g. less than 2 μm) the electric field does indeed penetrate through the substrate layers and undergoes absorption, from the glass supporting layer making up the majority of the slide. In this paper we show experimental evidence of the substrate contributions in ATR spectra and also a theoretical model giving insight into the spectral contributions of the substrate as a function of sample thickness.

  9. The inactivation principle: mathematical solutions minimizing the absolute work and biological implications for the planning of arm movements.

    PubMed

    Berret, Bastien; Darlot, Christian; Jean, Frédéric; Pozzo, Thierry; Papaxanthis, Charalambos; Gauthier, Jean Paul

    2008-10-01

    An important question in the literature focusing on motor control is to determine which laws drive biological limb movements. This question has prompted numerous investigations analyzing arm movements in both humans and monkeys. Many theories assume that among all possible movements the one actually performed satisfies an optimality criterion. In the framework of optimal control theory, a first approach is to choose a cost function and test whether the proposed model fits with experimental data. A second approach (generally considered as the more difficult) is to infer the cost function from behavioral data. The cost proposed here includes a term called the absolute work of forces, reflecting the mechanical energy expenditure. Contrary to most investigations studying optimality principles of arm movements, this model has the particularity of using a cost function that is not smooth. First, a mathematical theory related to both direct and inverse optimal control approaches is presented. The first theoretical result is the Inactivation Principle, according to which minimizing a term similar to the absolute work implies simultaneous inactivation of agonistic and antagonistic muscles acting on a single joint, near the time of peak velocity. The second theoretical result is that, conversely, the presence of non-smoothness in the cost function is a necessary condition for the existence of such inactivation. Second, during an experimental study, participants were asked to perform fast vertical arm movements with one, two, and three degrees of freedom. Observed trajectories, velocity profiles, and final postures were accurately simulated by the model. In accordance, electromyographic signals showed brief simultaneous inactivation of opposing muscles during movements. Thus, assuming that human movements are optimal with respect to a certain integral cost, the minimization of an absolute-work-like cost is supported by experimental observations. Such types of optimality

  10. Biological implications of lab-on-a-chip devices fabricated using multi-jet modelling and stereolithography processes

    NASA Astrophysics Data System (ADS)

    Zhu, Feng; Macdonald, Niall; Skommer, Joanna; Wlodkowic, Donald

    2015-06-01

    Current microfabrication methods are often restricted to two-dimensional (2D) or two and a half dimensional (2.5D) structures. Those fabrication issues can be potentially addressed by emerging additive manufacturing technologies. Despite rapid growth of additive manufacturing technologies in tissue engineering, microfluidics has seen relatively little developments with regards to adopting 3D printing for rapid fabrication of complex chip-based devices. This has been due to two major factors: lack of sufficient resolution of current rapid-prototyping methods (usually >100 μm ) and optical transparency of polymers to allow in vitro imaging of specimens. We postulate that adopting innovative fabrication processes can provide effective solutions for prototyping and manufacturing of chip-based devices with high-aspect ratios (i.e. above ration of 20:1). This work provides a comprehensive investigation of commercially available additive manufacturing technologies as an alternative for rapid prototyping of complex monolithic Lab-on-a-Chip devices for biological applications. We explored both multi-jet modelling (MJM) and several stereolithography (SLA) processes with five different 3D printing resins. Compared with other rapid prototyping technologies such as PDMS soft lithography and infrared laser micromachining, we demonstrated that selected SLA technologies had superior resolution and feature quality. We also for the first time optimised the post-processing protocols and demonstrated polymer features under scanning electronic microscope (SEM). Finally we demonstrate that selected SLA polymers have optical properties enabling high-resolution biological imaging. A caution should be, however, exercised as more work is needed to develop fully bio-compatible and non-toxic polymer chemistries.

  11. Impacts of climate, land use, and biological invasion on the ecology of immature Aedes mosquitoes: Implications for La Crosse emergence

    PubMed Central

    Leisnham, Paul; Juliano, Steven A.

    2012-01-01

    Arthropod-borne viruses (arboviruses) cause many diseases worldwide and their transmission is likely to change with land use and climate changes. La Crosse virus is historically transmitted by the native mosquito Aedes triseriatus (Say) in the upper Midwestern U.S., but the invasive congeners Aedes albopictus (Skuse) and Aedes japonicus (Theobald), which co-occur with A. triseriatus in water-holding containers, may be important accessory vectors in the Appalachian region where La Crosse encephalitis is an emerging disease. This review focuses on evidence for how climate, land use, and biological invasions may have direct abiotic and indirect community-level impacts on immature developmental stages (eggs and larvae) of Aedes mosquitoes. Because vector-borne diseases usually vary in space and time and are related to the ecology of the vector species, we propose that the ecology of its mosquito vectors, particularly at their immature stages, has played an important role in the emergence of La Crosse encephalitis in the Appalachian region and represents a model for investigating the effects of environmental changes on other vector-borne diseases. We summarize the health effects of La Crosse virus and associated socioeconomic costs that make it the most important native mosquito-borne disease in the U.S. We review of the transmission of La Crosse virus, and present evidence for the impacts of climate, land use, and biological invasions on Aedes mosquito communities. Last, we discuss important questions about the ecology of La Crosse virus mosquito vectors that may improve our understanding of the impacts of environmental changes on La Crosse virus and other arboviruses. PMID:22692799

  12. Physico-chemical and biological characterization of anopheline mosquito larval habitats (Diptera: Culicidae): implications for malaria control.

    PubMed

    Mereta, Seid Tiku; Yewhalaw, Delenasaw; Boets, Pieter; Ahmed, Abdulhakim; Duchateau, Luc; Speybroeck, Niko; Vanwambeke, Sophie O; Legesse, Worku; De Meester, Luc; Goethals, Peter L M

    2013-11-04

    A fundamental understanding of the spatial distribution and ecology of mosquito larvae is essential for effective vector control intervention strategies. In this study, data-driven decision tree models, generalized linear models and ordination analysis were used to identify the most important biotic and abiotic factors that affect the occurrence and abundance of mosquito larvae in Southwest Ethiopia. In total, 220 samples were taken at 180 sampling locations during the years 2010 and 2012. Sampling sites were characterized based on physical, chemical and biological attributes. The predictive performance of decision tree models was evaluated based on correctly classified instances (CCI), Cohen's kappa statistic (κ) and the determination coefficient (R2). A conditional analysis was performed on the regression tree models to test the relation between key environmental and biological parameters and the abundance of mosquito larvae. The decision tree model developed for anopheline larvae showed a good model performance (CCI = 84 ± 2%, and κ = 0.66 ± 0.04), indicating that the genus has clear habitat requirements. Anopheline mosquito larvae showed a widespread distribution and especially occurred in small human-made aquatic habitats. Water temperature, canopy cover, emergent vegetation cover, and presence of predators and competitors were found to be the main variables determining the abundance and distribution of anopheline larvae. In contrast, anopheline mosquito larvae were found to be less prominently present in permanent larval habitats. This could be attributed to the high abundance and diversity of natural predators and competitors suppressing the mosquito population densities. The findings of this study suggest that targeting smaller human-made aquatic habitats could result in effective larval control of anopheline mosquitoes in the study area. Controlling the occurrence of mosquito larvae via drainage of permanent wetlands may not be a good management

  13. Evaluation of the biological differences of canine and human factor VIII in gene delivery: implications in human hemophilia treatment

    PubMed Central

    Wang, Qizhao; Dong, Biao; Firrman, Jenni; Wu, Wenman; Roberts, Sean; Moore, Andrea Rossi; Liu, LinShu; Chin, Mario P.S.; Diao, Yong; Kost, Joseph; Xiao, Weidong

    2016-01-01

    The canine is the most important large animal model for testing novel hemophilia A(HA) treatment. It is often necessary to use canine factor VIII (cFIII) gene or protein for the evaluation of HA treatment in the canine model. However, the different biological properties between cFVIII and human FVIII(hFVIII) indicated that the development of novel HA treatment may require careful characterization of non-human FVIII. To investigate whether the data obtained using cFVIII can translate to HA treatment in human, we analyzed the differential biological properties of canine heavy chain (cHC) and light chain (cLC) by comparing with human HC (hHC) and LC (hLC). The secretion of cHC was 5~30 fold higher than hHC, with or without LCs. cHC+hLC group exhibited ~18-fold increase in coagulation activity compared with hHC+hLC delivery by recombinant adeno-associated viral vectors. Unlike hHC, the secretion of cHC was independent of LCs. cLC improves the specific activity of FVIII by 2~3-fold compared with hLC. Moreover, the cLC but not cHC, contributes the high stability of cFVIII. Our results suggested that the cFVIII expression results in the canine model should be interpreted with caution as the cHC secreted more efficiently than hHC and cLC exhibited a more active and stable phenotype than hLC. PMID:27064790

  14. Evaluation of the biological differences of canine and human factor VIII in gene delivery: implications in human hemophilia treatment.

    PubMed

    Wang, Q; Dong, B; Firrman, J; Wu, W; Roberts, S; Moore, A R; Liu, L S; Chin, M P S; Diao, Y; Kost, J; Xiao, W

    2016-07-01

    The canine is the most important large animal model for testing novel hemophilia A (HA) treatment. It is often necessary to use canine factor VIII (cFIII) gene or protein for the evaluation of HA treatment in the canine model. However, different biological properties between cFVIII and human FVIII (hFVIII) indicated that the development of novel HA treatment may require careful characterization of non-human FVIII. To investigate whether the data obtained using cFVIII can translate to HA treatment in human, we analyzed the differential biological properties of canine heavy chain (cHC) and light chain (cLC) by comparing with human heavy chain (hHC) and light chain (hLC). The secretion of cHC was 5-30-fold higher than hHC, with or without light chains (LCs). cHC+hLC group exhibited ~18-fold increase in coagulation activity compared with hHC+hLC delivery by recombinant adeno-associated viral vectors. Unlike hHC, the secretion of cHC was independent of LCs. cLC improves the specific activity of FVIII by two- to threefold compared with hLC. Moreover, the cLC, but not cHC, contributes to the higher stability of cFVIII. Our results suggested that the cFVIII expression results in the canine model should be interpreted with caution as the cHC secreted more efficiently than hHC and cLC exhibited a more active and stable phenotype than hLC.

  15. T3 Regulates a Human Macrophage-Derived TSH-β Splice Variant: Implications for Human Bone Biology.

    PubMed

    Baliram, R; Latif, R; Morshed, S A; Zaidi, M; Davies, T F

    2016-09-01

    TSH and thyroid hormones (T3 and T4) are intimately involved in bone biology. We have previously reported the presence of a murine TSH-β splice variant (TSH-βv) expressed specifically in bone marrow-derived macrophages and that exerted an osteoprotective effect by inducing osteoblastogenesis. To extend this observation and its relevance to human bone biology, we set out to identify and characterize a TSH-β variant in human macrophages. Real-time PCR analyses using human TSH-β-specific primers identified a 364-bp product in macrophages, bone marrow, and peripheral blood mononuclear cells that was sequence verified and was homologous to a human TSH-βv previously reported. We then examined TSH-βv regulation using the THP-1 human monocyte cell line matured into macrophages. After 4 days, 46.1% of the THP-1 cells expressed the macrophage markers CD-14 and macrophage colony-stimulating factor and exhibited typical morphological characteristics of macrophages. Real-time PCR analyses of these cells treated in a dose-dependent manner with T3 showed a 14-fold induction of human TSH-βv mRNA and variant protein. Furthermore, these human TSH-βv-positive cells, induced by T3 exposure, had categorized into both M1 and M2 macrophage phenotypes as evidenced by the expression of macrophage colony-stimulating factor for M1 and CCL-22 for M2. These data indicate that in hyperthyroidism, bone marrow resident macrophages have the potential to exert enhanced osteoprotective effects by oversecreting human TSH-βv, which may exert its local osteoprotective role via osteoblast and osteoclast TSH receptors.

  16. Reproductive biology and implications for management of the painted sweetlips Diagramma pictum in the southern Arabian Gulf.

    PubMed

    Grandcourt, E M; Al Abdessalaam, T Z; Francis, F; Al Shamsi, A T

    2011-09-01

    The reproductive biology of the painted sweetlips Diagramma pictum was determined from 487 individuals collected between January and December 2010 in the southern Arabian Gulf. There was no evidence of sex change and the combination of histological results with the sex composition of the size and age structures indicated a gonochoristic sexual pattern. There were peaks in gonado-somatic indices for females in March and October with spawning occurring during two seasons (April to May and November). The mean size and age at sexual maturity (L(m50) and A(m50) ) were 35·7 cm fork length (L(F) ) and 2·9 years for females and 26·7 cm L(F) and 0·5 years for males. The maximum recorded age (11 years) and small mean size and young age at sexual maturity for males may be a direct result of intensive demersal fishing in the southern Arabian Gulf. There was an exponential increase in the cumulative reproductive potential with size and a linear increase with age for both sexes. The mean L(F) (L(c50) ) at which D. pictum became vulnerable to capture was 33·3 cm, which corresponded to only 3 and 7% of the cumulative reproductive potential of males and females, respectively. Size-specific and age-specific reproductive potential indicated that conventional regulations that equate the mean size at first capture to sexual maturation are unsuitable for the management of D. pictum. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  17. Biological Cost of Single and Multiple Norfloxacin Resistance Mutations in Escherichia coli Implicated in Urinary Tract Infections

    PubMed Central

    Lindgren, Patricia Komp; Marcusson, Linda L.; Sandvang, Dorthe; Frimodt-Møller, Niels; Hughes, Diarmaid

    2005-01-01

    Resistance to fluoroquinolones in urinary tract infection (UTIs) caused by Escherichia coli is associated with multiple mutations, typically those that alter DNA gyrase and DNA topoisomerase IV and those that regulate AcrAB-TolC-mediated efflux. We asked whether a fitness cost is associated with the accumulation of these multiple mutations. Mutants of the susceptible E. coli UTI isolate Nu14 were selected through three to five successive steps with norfloxacin. Each selection was performed with the MIC of the selected strain. After each selection the MIC was measured; and the regions of gyrA, gyrB, parC, and parE, previously associated with resistance mutations, and all of marOR and acrR were sequenced. The first selection step yielded mutations in gyrA, gyrB, and marOR. Subsequent selection steps yielded mutations in gyrA, parE, and marOR but not in gyrB, parC, or acrR. Resistance-associated mutations were identified in almost all isolates after selection steps 1 and 2 but in less than 50% of isolates after subsequent selection steps. Selected strains were competed in vitro, in urine, and in a mouse UTI infection model against the starting strain, Nu14. First-step mutations were not associated with significant fitness costs. However, the accumulation of three or more resistance-associated mutations was usually associated with a large reduction in biological fitness, both in vitro and in vivo. Interestingly, in some lineages a partial restoration of fitness was associated with the accumulation of additional mutations in late selection steps. We suggest that the relative biological costs of multiple mutations may influence the evolution of E. coli strains that develop resistance to fluoroquinolones. PMID:15917531

  18. Pulmonary adenocarcinoma: implications of the recent advances in molecular biology, treatment and the IASLC/ATS/ERS classification.

    PubMed

    Revannasiddaiah, Swaroop; Thakur, Priyanka; Bhardwaj, Bhaskar; Susheela, Sridhar Papaiah; Madabhavi, Irappa

    2014-10-01

    A decade ago, lung cancer could conveniently be classified into two broad categories-either the small cell lung carcinoma (SCLC), or the non-small cell lung carcinoma (NSCLC), mainly to assist in further treatment related decision making. However, the understanding regarding the eligibility of adenocarcinoma histology for treatments with agents such as pemetrexed and bevacizumab made it a necessity for NSCLC to be classified into more specific sub-groups. Then, the availability of molecular targeted therapy with oral tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib not only further emphasized the need for accurate sub-classification of lung cancer, but also heralded the important role of molecular profiling of lung adenocarcinomas. Given the remarkable advances in molecular biology, oncology and radiology, a need for felt for a revised classification for lung adenocarcinoma, since the existing World Health Organization (WHO) classification of lung cancer, published in the year 2004 was mainly a pathological system of classification. Thus, there was a combined effort by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS) and the European Respiratory Society (ERS) with an effort to inculcate newly established perspectives from clinical, molecular and radiological aspects in evolving a modern classification for lung adenocarcinomas. This review provides a summary of the recent advances in molecular biology and molecular targeted therapy with respect to lung adenocarcinoma. Also, a brief summation of the salient recommendations provided in the IASLC/ATS/ERS classification of lung adenocarcinomas is provided. Lastly, a discussion regarding the future prospects with lung adenocarcinoma is included.

  19. Pulmonary adenocarcinoma: implications of the recent advances in molecular biology, treatment and the IASLC/ATS/ERS classification

    PubMed Central

    Thakur, Priyanka; Bhardwaj, Bhaskar; Susheela, Sridhar Papaiah; Madabhavi, Irappa

    2014-01-01

    A decade ago, lung cancer could conveniently be classified into two broad categories—either the small cell lung carcinoma (SCLC), or the non-small cell lung carcinoma (NSCLC), mainly to assist in further treatment related decision making. However, the understanding regarding the eligibility of adenocarcinoma histology for treatments with agents such as pemetrexed and bevacizumab made it a necessity for NSCLC to be classified into more specific sub-groups. Then, the availability of molecular targeted therapy with oral tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib not only further emphasized the need for accurate sub-classification of lung cancer, but also heralded the important role of molecular profiling of lung adenocarcinomas. Given the remarkable advances in molecular biology, oncology and radiology, a need for felt for a revised classification for lung adenocarcinoma, since the existing World Health Organization (WHO) classification of lung cancer, published in the year 2004 was mainly a pathological system of classification. Thus, there was a combined effort by the International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS) and the European Respiratory Society (ERS) with an effort to inculcate newly established perspectives from clinical, molecular and radiological aspects in evolving a modern classification for lung adenocarcinomas. This review provides a summary of the recent advances in molecular biology and molecular targeted therapy with respect to lung adenocarcinoma. Also, a brief summation of the salient recommendations provided in the IASLC/ATS/ERS classification of lung adenocarcinomas is provided. Lastly, a discussion regarding the future prospects with lung adenocarcinoma is included. PMID:25349702

  20. Adsorption of small biological molecules on silica from diluted aqueous solutions: Quantitative characterization and implications to the Bernal's hypothesis

    NASA Astrophysics Data System (ADS)

    Basiuk, Vladimir A.; Gromovoy, Taras Yu.; Khil'Chevskaya, Elena G.

    1995-08-01

    To describe quantitatively the adsorption of prebiotically important compounds of low molecular weight (amino acids, short linear peptides, cyclic dipeptides, the Krebs's cycle and other carboxylic acids, nucleosides and related phosphates) on silica surface from diluted neutral aqueous solutions, equilibrium constants (K) and free energies (-ΔG) of adsorption were determined from the retention values measured by means of high-performance liquid chromatography on a silica gel column and from the isotherms measured under static conditions. For most carboxylic acids (including amino acids and linear peptides) -ΔG values were negative and K<1, thus showing very weak adsorption. Cyclic dipeptides (2,5-piperazinediones) exhibited higher adsorbability; -ΔG>0 and K>1 were found for most of them. Influence of the structure of α-substituent on the adsorbability is analyzed. A linear dependence of -ΔG on the number of aliphatic carbon atoms in a sorbate molecule was found for the series of aliphatic bifunctional amino acids, related dipeptides and 2,5-piperazinediones, as well as for the row from glycine to triglycyl glycine. The adsorption of nucleosides and their phosphates is characterized by much higherK and -ΔG values (of the order of 102 and 104, respectively). The adsorption data available from our work and literature are summarized and discussed with implications to the Bernal's hypothesis on the roles of solid surfaces in the prebiotic formation of biopolymers from monomeric ‘building blocks’.

  1. Non-migratory breeding by isolated green sea turtles ( Chelonia mydas) in the Indian Ocean: biological and conservation implications

    NASA Astrophysics Data System (ADS)

    Whiting, Scott D.; Murray, Wendy; Macrae, Ismail; Thorn, Robert; Chongkin, Mohammad; Koch, Andrea U.

    2008-04-01

    Green sea turtles ( Chelonia mydas) are renowned for their long-distance migrations but have less fame for short-distance migrations or non-migratory behavior. We present satellite telemetric evidence from Cocos (Keeling) Islands, Indian Ocean for the first predominantly non-migratory green sea turtle ( C. mydas) population. The mean migration distance from the nesting beach to the foraging grounds was 35.5 km with a maximum mean transit time of 3.4 days. The behavior of this population has major implications for our general understanding of green turtle behavior and their life cycle and for conservation. Firstly, these results indicate a level of juvenile or adult non-breeding homing behavior from the open ocean to foraging grounds adjacent to their natal nesting beach. Secondly, a non-migratory breeding phase reduces the consumption of reproductive energy utilized, potentially resulting in higher fecundity for this population. Thirdly, the close proximity of the nesting and foraging habitats allows for uniformity in management and conservation strategies rarely possible for wide-ranging green turtle populations.

  2. Non-migratory breeding by isolated green sea turtles (Chelonia mydas) in the Indian Ocean: biological and conservation implications.

    PubMed

    Whiting, Scott D; Murray, Wendy; Macrae, Ismail; Thorn, Robert; Chongkin, Mohammad; Koch, Andrea U

    2008-04-01

    Green sea turtles (Chelonia mydas) are renowned for their long-distance migrations but have less fame for short-distance migrations or non-migratory behavior. We present satellite telemetric evidence from Cocos (Keeling) Islands, Indian Ocean for the first predominantly non-migratory green sea turtle (C. mydas) population. The mean migration distance from the nesting beach to the foraging grounds was 35.5 km with a maximum mean transit time of 3.4 days. The behavior of this population has major implications for our general understanding of green turtle behavior and their life cycle and for conservation. Firstly, these results indicate a level of juvenile or adult non-breeding homing behavior from the open ocean to foraging grounds adjacent to their natal nesting beach. Secondly, a non-migratory breeding phase reduces the consumption of reproductive energy utilized, potentially resulting in higher fecundity for this population. Thirdly, the close proximity of the nesting and foraging habitats allows for uniformity in management and conservation strategies rarely possible for wide-ranging green turtle populations.

  3. Physico-chemical and biological characterization of anopheline mosquito larval habitats (Diptera: Culicidae): implications for malaria control

    PubMed Central

    2013-01-01

    Background A fundamental understanding of the spatial distribution and ecology of mosquito larvae is essential for effective vector control intervention strategies. In this study, data-driven decision tree models, generalized linear models and ordination analysis were used to identify the most important biotic and abiotic factors that affect the occurrence and abundance of mosquito larvae in Southwest Ethiopia. Methods In total, 220 samples were taken at 180 sampling locations during the years 2010 and 2012. Sampling sites were characterized based on physical, chemical and biological attributes. The predictive performance of decision tree models was evaluated based on correctly classified instances (CCI), Cohen’s kappa statistic (κ) and the determination coefficient (R2). A conditional analysis was performed on the regression tree models to test the relation between key environmental and biological parameters and the abundance of mosquito larvae. Results The decision tree model developed for anopheline larvae showed a good model performance (CCI = 84 ± 2%, and κ = 0.66 ± 0.04), indicating that the genus has clear habitat requirements. Anopheline mosquito larvae showed a widespread distribution and especially occurred in small human-made aquatic habitats. Water temperature, canopy cover, emergent vegetation cover, and presence of predators and competitors were found to be the main variables determining the abundance and distribution of anopheline larvae. In contrast, anopheline mosquito larvae were found to be less prominently present in permanent larval habitats. This could be attributed to the high abundance and diversity of natural predators and competitors suppressing the mosquito population densities. Conclusions The findings of this study suggest that targeting smaller human-made aquatic