Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “drug development”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7

Monitors Track Vital Signs for Fitness and Safety

Have you ever felt nauseous reading a book in the back seat of a car? Or woken from a deep sleep feeling disoriented, unsure which way is up? Momentary mixups like these happen when the sensory systems that track the body's orientation in space become confused. (In the case of the backseat bookworm, the conflict arises when the reader s inner ear, part of the body s vestibular system, senses the car s motion while her eyes are fixed on the stationary pages of the book.) Conditions like motion sickness are common on Earth, but they also present a significant challenge to astronauts in space. Human sensory systems use the pull of gravity to help determine orientation. In the microgravity environment onboard the International Space Station, for example, the body experiences a period of confusion before it adapts to the new circumstances. (In space, even the body s proprioceptive system, which tells the brain where the arms and legs are oriented without the need for visual confirmation, goes haywire, meaning astronauts sometimes lose track of where their limbs are when they are not moving them.) This Space Adaptation Syndrome affects a majority of astronauts, even experienced ones, causing everything from mild disorientation to nausea to severe vomiting. "It can be quite debilitating," says William Toscano, a research scientist in NASA s Ames Research Center Psychophysiology Laboratory, part of the Center s Human Systems Integration Division. "When this happens, as you can imagine, work proficiency declines considerably." Since astronauts cannot afford to be distracted or incapacitated during critical missions, NASA has explored various means for preventing and countering motion sickness in space, including a range of drug treatments. Many effective motion sickness drugs, however, cause undesirable side effects, such as drowsiness. Toscano and his NASA colleague, Patricia Cowings, have developed a different approach: Utilizing biofeedback training methods, the pair can teach astronauts, military pilots, and others susceptible to motion sickness to self-regulate their own physiological responses and suppress the unpleasant symptoms. This NASA-patented method invented by Cowings is called the Autogenic Feedback Training Exercise (ATFE), and several studies have demonstrated its promise

Source record↗

Very high CO2 reduces photosynthesis, dark respiration and yield in wheat

Although terrestrial CO2 concentrations, [CO2] are not expected to reach 1000 micromoles mol-1 for many decades, CO2 levels in closed systems such as growth chambers and glasshouses, can easily exceed this concentration. CO2 levels in life support systems in space can exceed 10000 micromoles mol-1 (1%). Here we studied the effect of six CO2 concentrations, from ambient up to 10000 micromoles mol-1, on seed yield, growth and gas exchange of two wheat cultivars (USU-Apogee and Veery-l0). Elevating [CO2] from 350 to 1000 micromoles mol-1 increased seed yield (by 33%), vegetative biomass (by 25%) and number of heads m-2 (by 34%) of wheat plants. Elevation of [CO2] from 1000 to 10000 micromoles mol-1 decreased seed yield (by 37%), harvest index (by 14%), mass per seed (by 9%) and number of seeds per head (by 29%). This very high [CO2] had a negligible, non-significant effect on vegetative biomass, number of heads m-2 and seed mass per head. A sharp decrease in seed yield, harvest index and seeds per head occurred by elevating [CO2] from 1000 to 2600 micromoles mol-1. Further elevation of [CO2] from 2600 to 10000 micromoles mol-1 caused a further but smaller decrease. The effect of CO2 on both wheat cultivars was similar for all growth parameters. Similarly there were no differences in the response to high [CO2] between wheat grown hydroponically in growth chambers under fluorescent lights and those grown in soilless media in a glasshouse under sunlight and high pressure sodium lamps. There was no correlation between high [CO2] and ethylene production by flag leaves or by wheat heads. Therefore, the reduction in seed set in wheat plants is not mediated by ethylene. The photosynthetic rate of whole wheat plants was 8% lower and dark respiration of the wheat heads 25% lower when exposed to 2600 micromoles mol-1 CO2 compared to ambient [CO2]. It is concluded that the reduction in the seed set can be mainly explained by the reduction in the dark respiration in wheat heads, when most of the respiration is functional and is needed for seed development.

NASA Discipline Life Support Systems↗

Inhibition of gravitropism in oat coleoptiles by the calcium chelator, ethyleneglycol-bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid

A treatment period as brief as 8 h in 10(-3) M EGTA completely blocks gravitropism in 70-80% of the treated coleoptiles of oats (Avena sativa L. cv. Garry) without inhibiting growth. Only about 10% of the plants perfused in water failed to exhibit gravitropism. Subsequent perfusion of EGTA-treated plants with calcium completely restores gravitropism; post-perfusion with water does not. After perfusion in water for 10 h, gravistimulated oat coleoptile segments show the same asymmetry of 45Ca distribution as reported earlier for non-perfused coleoptiles and sunflower hypocotyls. The degree of this asymmetry is reduced in those coleoptiles partially inhibited by perfusion in EGTA and is essentially absent in those coleoptiles completely inhibited by EGTA. The fact that calcium reverses the inhibitory effects of EGTA on gravitropism indicates that the inhibition was probably due to a reduction in the availability of free calcium required for one or more of the transduction steps of gravitropism.

Egtazic Acid/pharmacology↗

Elevated carbon dioxide influences yield and photosynthetic responses of hydroponically-grown sweetpotato

The response of 'TI-155' and 'Georgia Jet' sweetpotato cultivars to elevated CO2 concentrations of 400 (ambient), 750 and 1000 micromoles mol-1 were evaluated under controlled environment conditions using the nutrient film technique (NFT). Growth chamber conditions included photosynthetic photon flux (PPF) of 600 micromoles m-2 s-1, 14/10 light/dark period, and 70% +/- 5% RH. Plants were grown using a modified half-Hoagland nutrient solution with a pH range of 5.5-6.0 and an electrical conductivity of 0.12 S m-1. Gas exchange measurements were made using infrared gas analysis, an open-flow gas exchange system, and a controlled-climate cuvette. Photosynthetic (Pn) measurements were made at CO2 ranges of 50 to 1000 micromoles mol-1. Storage root yield/plant increased with CO2 up to 750 but declined at 1000 micromoles mol-1. Storage root dry matter (DM) and foliage dry weight increased with increasing CO2. Harvest index (HI) for both cultivars was highest at 750 micromoles mol-1. The PPF vs Pn curves were typical for C3 plants with saturation occurring at approximately 600 micromoles m-2 s-1. CO2 concentration did not significantly influence net Pn, transpiration, water-use-efficiency (WUE), and stomatal conductance. As measurement CO2 concentration increased, net Pn and WUE increased while transpiration and stomatal conductance decreased.

Solanaceae/drug effects/growth & development↗

Health Maintenance System (HMS) Hardware Research, Design, and Collaboration

The Space Life Sciences division (SLSD) concentrates on optimizing a crew member's health. Developments are translated into innovative engineering solutions, research growth, and community awareness. This internship incorporates all those areas by targeting various projects. The main project focuses on integrating clinical and biomedical engineering principles to design, develop, and test new medical kits scheduled for launch in the Spring of 2011. Additionally, items will be tagged with Radio Frequency Interference Devices (RFID) to keep track of the inventory. The tags will then be tested to optimize Radio Frequency feed and feed placement. Research growth will occur with ground based experiments designed to measure calcium encrusted deposits in the International Space Station (ISS). The tests will assess the urine calcium levels with Portable Clinical Blood Analyzer (PCBA) technology. If effective then a model for urine calcium will be developed and expanded to microgravity environments. To support collaboration amongst the subdivisions of SLSD the architecture of the Crew Healthcare Systems (CHeCS) SharePoint site has been redesigned for maximum efficiency. Community collaboration has also been established with the University of Southern California, Dept. of Aeronautical Engineering and the Food and Drug Administration (FDA). Hardware disbursements will transpire within these communities to support planetary surface exploration and to serve as an educational tool demonstrating how ground based medicine influenced the technological development of space hardware.

Gonzalez, Stefanie M.↗

Chemoprevention of Radiation Induced Rat Mammary Neoplasms

Radiations encountered in space include protons and heavy ions such as iron as well as their secondaries. The relative biological effect (RBE) of these ions is not known, particularly at the doses and dose-rates expected for planetary missions. Neutrons, are not particularly relevant to space travel, but have been found experimentally to have an increase in their RBE with decreasing dose. If a similar trend of increasing RBE with decreasing dose is present for heavy ions and protons during irradiation in space, the small doses received during space travel could potentially have substantial carcinogenic risk. Clearly more investigation of the effects of heavy ions and protons is needed before accurate risk assessment for prolonged travel in space can be done. One means to mitigate the increased risk of cancer due to radiation exposure in space is by developing effective countermeasures that can reduce the incidence of tumor development. Tamoxifen has recently been shown to be an effective chemopreventive agent in both animal models and humans for the prevention of mammary tumors. Tamoxifen is a unique drug, with a highly specific mechanism of action affecting a specific radiation-sensitive population of epithelial cells in the mammary gland. In human studies, the annual incidence of a primary tumor in the contralateral breast of women with previous breast cancer is about 8 per 1000, making them an exceedingly high-risk group for the development of breast cancer. In this high risk group, treated with tamoxifen, daily, for 2 years, the incidence of a new primary tumor in the contralateral breast was approximately one third of that noted in the non-tamoxifen treatment group. Tamoxifen antagonizes the action of estrogen by competing for the nuclear receptor complex thereby altering the association of the receptor complex and nuclear binding sites. Its effects in reducing the development of breast cancer could be accomplished by controlling clinically undetectable microcancers, arresting preneoplastic lesions, or correcting abnormal environments which predispose to high risk of malignant transformation.

Huso, David L.↗

Early embryo development in Fucus distichus is auxin sensitive

Auxin and polar auxin transport have been implicated in controlling embryo development in land plants. The goal of these studies was to determine if auxin and auxin transport are also important during the earliest stages of development in embryos of the brown alga Fucus distichus. Indole-3-acetic acid (IAA) was identified in F. distichus embryos and mature tissues by gas chromatography-mass spectroscopy. F. distichus embryos accumulate [(3)H]IAA and an inhibitor of IAA efflux, naphthylphthalamic acid (NPA), elevates IAA accumulation, suggesting the presence of an auxin efflux protein complex similar to that found in land plants. F. distichus embryos normally develop with a single unbranched rhizoid, but growth on IAA leads to formation of multiple rhizoids and growth on NPA leads to formation of embryos with branched rhizoids, at concentrations that are active in auxin accumulation assays. The effects of IAA and NPA are complete before 6 h after fertilization (AF), which is before rhizoid germination and cell division. The maximal effects of IAA and NPA are between 3.5 and 5 h AF and 4 and 5.5 h AF, respectively. Although, the location of the planes of cell division was significantly altered in NPA- and IAA-treated embryos, these abnormal divisions occurred after abnormal rhizoid initiation and branching was observed. The results of this study suggest that auxin acts in the formation of apical basal patterns in F. distichus embryo development.

Non-NASA Center↗

A Manual Control Test for the Detection and Deterrence of Impaired Drivers

A brief manual control test and a decision strategy were developed, laboratory tested, and field validated which provide a means for detecting human operator impairment from alcohol or other drugs. The test requires the operator to stabilize progressively unstable controlled element dynamics. Control theory and experimental data verify that the human operator's control ability on this task is constrained by basic cybernetic characteristics, and that task performance is reliably affected by impairment effects on these characteristics. Assessment of human operator control ability is determined by a statistically based decision strategy. The operator is allowed several chances to exceed a preset pass criterion. Procedures are described for setting the pass criterion based on individual ability and a desired unimpaired failure rate. These procedures were field tested with apparatus installed in automobiles that were designed to discourage drunk drivers from operating their vehicles. This test program demonstrated that the control task and detection strategy could be applied in a practical setting to screen human operators for impairment in their basic cybernetic skills.

Stein, A. C.↗

Enhanced gravitropism of roots with a disrupted cap actin cytoskeleton

The actin cytoskeleton has been proposed to be a major player in plant gravitropism. However, understanding the role of actin in this process is far from complete. To address this problem, we conducted an analysis of the effect of Latrunculin B (Lat B), a potent actin-disrupting drug, on root gravitropism using various parameters that included detailed curvature kinetics, estimation of gravitropic sensitivity, and monitoring of curvature development after extended clinorotation. Lat B treatment resulted in a promotion of root curvature after a 90 degrees reorientation in three plant species tested. More significantly, the sensitivity of maize (Zea mays) roots to gravity was enhanced after actin disruption, as determined from a comparison of presentation time of Lat B-treated versus untreated roots. A short 10-min gravistimulus followed by extended rotation on a 1-rpm clinostat resulted in extensive gravitropic responses, manifested as curvature that often exceeded 90 degrees. Application of Lat B to the cap or elongation zone of maize roots resulted in the disruption of the actin cytoskeleton, which was confined to the area of localized Lat B application. Only roots with Lat B applied to the cap displayed the strong curvature responses after extended clinorotation. Our study demonstrates that disrupting the actin cytoskeleton in the cap leads to the persistence of a signal established by a previous gravistimulus. Therefore, actin could function in root gravitropism by providing a mechanism to regulate the proliferation of a gravitropic signal originating from the cap to allow the root to attain its correct orientation or set point angle.

NASA Discipline Plant Biology↗

Response of potatoes to nitrogen concentrations differ with nitrogen forms

Two separate experiments were conducted to investigate plant growth and mineral composition of potatoes (Solanum tuberosum L.) at varied solution concentrations of nitrate (NO3-) and ammonium (NH4+). Each experiment evaluated five nitrogen (N) concentrations of 0.5, 2, 4, 8, and 12 mM, which were maintained with a non-recirculating nutrient film system in controlled environment. Plants were harvested on day 42 with NO3-; and day 35 with NH4+ after transplanting of tissue culture plantlets, and growth measurements were taken as leaf area, tuber number, and dry weights of different parts. With NO3-, plant growth was greatest and similar at 2, 4, and 8 mM of N whereas with NH4+, plant growth was best only at 2 and 4 mM of N. At 12 mM of N, plants exhibited interveinal ammonium toxicity with NH4+ nutrition, but healthy growth appearance with NO3- nutrition. With either N form, total N concentrations in tissues tended to increase with increased N concentrations, and tissue phosphorus (P) concentrations were reduced at 0.5 and 2 mM of N. Tissue concentrations of calcium (Ca), magnesium (Mg), and sulfur (S) changed only slightly at particular N concentrations, yet changed substantially with different N forms. The data indicate that the optimal ranges of N concentrations in both solution and tissues are wider and higher with NO3- than with NH4+ nutrition, and thus a careful control of NH4+ concentrations is necessary to minimize possible ammonium toxicity to potato plants.

NASA Discipline Life Support Systems↗

Cell Radiation Experiment System

The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.

Morrison, Dennis R.↗

Effects of natural and synthetic auxins on the gravitropic growth habit of roots in two auxin-resistant mutants of Arabidopsis, axr1 and axr4: evidence for defects in the auxin influx mechanism of axr4

The partially agravitropic growth habit of roots of an auxin-resistant mutant of Arabidopsis thaliana, axr4, was restored by the addition of 30-300 nM 1-naphthaleneacetic acid (NAA) to the growth medium. Neither indole 3-acetic acid (IAA) nor 2,4-dichlorophenoxyacetic acid (2,4-D) showed such an effect. Growth of axr4 roots was resistant to IAA and 2,4-D, but not at all to NAA. The differential effects of the three auxins suggest that the defects of axr4 result from a lower auxin influx into its cells. The partially agravitropic growth habit of axr1 roots, which was less severe than that of axr4 roots, was only slightly affected by the three auxins in the growth medium at concentrations up to 300 nM; growth of axr1 roots was resistant to all three of the auxins. These results suggest that the lesion of axrl mutants is different from that of axr4.

Arabidopsis/drug effects/genetics/growth & develop↗

Rapid susceptibility testing of mycobacterium avium complex and mycobacterium tuberculosis isolated from AIDS patients

In ominous projections issued by both U.S. Public Health Service and the World Health Organization, the epidemic of the Human Immunodeficiency Virus (HIV) infection will continue to rise more rapidly worldwide than predicted earlier. The Acquired Immunodeficiency Syndrome (AIDS) patients are susceptible to diseases called opportunistic infections of which tuberculosis and M. avium Complex (MAC) infection are most common. This has created an urgent need to uncover new drugs for the treatment of these infections. In the seventies, NASA scientists at Goddard Space Flight Center, Greenbelt, Maryland, had adopted a biochemical indicator, adenosine triphosphate (ATP), to detect presence of life in extraterrestrial space. Therefore, we proposed to develop ATP assay technique to determine sensitivity of antibacterial compounds against MAC and M. tuberculosis. The work was initiated in June 1992. In the last report, we described our efforts in developing ATP assay method using MAC. Studies were continued further, and during the period of this report, we established the relationship between colony forming units and ATP levels of these organisms during the growth cycle. Also, we evaluated the effects of standard antimycobacterial drugs using ATP assay technique and compared the results with those obtained with conventional tube dilution proportional method.

Dhople, Arvind M.↗

Detailed Test Objectives (DTOs) and Detailed Supplementary Objectives (DSOs)

The purpose of this experiment is to demonstrate the performance and operations of the GPS during orbiter ascent, entry and landing phases utilizing a modified military GPS receiver processor and the existing orbiter GPS antennas. The purpose of this experiment is to demonstrate the capability to perform a manually controlled landing in the presence of a crosswind. Changes in gastrointestinal function and physiology as a result of spaceflight affect drug absorption and the bioavailability of oral medications, which can compromise therapeutic effectiveness. This DSO will lead to the design and development of effective pharmocological countermeasures and therapeutic adjustments for spaceflight. A previous observation suggested that discordant sensory stimuli caused by an unusual motion environment disrupted spatial orientation and balance control in a returning crewmember by triggering a state change in central vestibular processing. The findings of the current investigation are expected to demonstrate the degree to which challenging motion environments may affect post-flight (re)adaptation to gravity.

Source record↗

Nanotechnologv Enabled Biological and Chemical Sensors

Nanotechnology is an enabling technology that will impact almost all economic sectors: one of the most important and with great potential is the health/medical sector. - Nanomaterials for drug delivery - Early warning sensors - Implantable devices - Artificial parts with improved characteristics Carbon nanotubes and nanofibers show promise for use in sensor development, electrodes and other biomedical applications.

Koehne, Jessica↗

Lunar Health Monitor (LHM)

Orbital Research, Inc., has developed a low-profile, wearable sensor suite for monitoring astronaut health in both intravehicular and extravehicular activities. The Lunar Health Monitor measures respiration, body temperature, electrocardiogram (EKG) heart rate, and other cardiac functions. Orbital Research's dry recording electrode is central to the innovation and can be incorporated into garments, eliminating the need for conductive pastes, adhesives, or gels. The patented dry recording electrode has been approved by the U.S. Food and Drug Administration. The LHM is easily worn under flight gear or with civilian clothing, making the system completely versatile for applications where continuous physiological monitoring is needed. During Phase II, Orbital Research developed a second-generation LHM that allows sensor customization for specific monitoring applications and anatomical constraints. Evaluations included graded exercise tests, lunar mission task simulations, functional battery tests, and resting measures. The LHM represents the successful integration of sensors into a wearable platform to capture long-duration and ambulatory physiological markers.

Lisy, Frederick J.↗

Prolonged weightlessness (300 plus days) and cardiac performance in primates. 1: Neuro-humoral mechanisms in the control of cardiac and vascular performance in conscious animals

Research during the period 1 Oct. 1971 to 1 Oct. 1972 is reported. Studies discussed include: development of techniques for instrumentation of dogs and other animals, effects of temporary application of lower body negative pressure, and effect of infusing selected drugs on ventricular performance.

Hawthorne, E. W.↗

Motion sickness in cats - A symptom rating scale used in laboratory and flight tests

The cat is proposed as a model for the study of motion and space sickness. Development of a scale for rating the motion sickness severity in the cat is described. The scale is used to evaluate an antimotion sickness drug, d-amphetamine plus scopolamine, and to determine whether it is possible to predict sickness susceptibility during parabolic flight, including zero-G maneuvers, from scores obtained during ground based trials.

Suri, K. B.↗