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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.

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313 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

Inflight Pharmacokinetic and Pharmacodynamic Responses to Medications Commonly Used in Spaceflight

Researchers do not know if medications act the same in the spaceflight environment as they do on Earth. Aspects of the spaceflight environment (low gravity, radiation exposure, closed environment, stress) have been shown to alter human physiology. Some of these physiological changes could be expected to alter either pharmacokinetics (PK, how the body absorbs, distributes, metabolizes and excretes administered medications) or pharmacodynamics (PD, receptors or signaling systems that are the targets of medication action). Anecdotal data has suggested that, at least for certain medications or indications, inflight medication efficacy is poor. In order to prepare for exploration missions where speedy evacuation to Earth may not be a possibility, the likelihood of unexpected medication action must be determined.

Wotring, V. E.↗
NASA NTRSDate not supplied

Printed Electrochemical Sensor for Quantifying Bone Density Loss in Microgravity

Printed electrochemical biosensors have been developed for astronaut point-of-care testing. Our fabrication approach is complimentary with in-space manufacturing for an on-demand and hands-free fabrication process. These sensors are developed using a combination of thin film materials printing and 3D printing and are comprised of carbon nanotube, gold nanoparticle, silver nanoparticle and dielectric inks to make traditional electrochemical sensor devices. Initial prototyped printed electrochemical sensors demonstrate good electrochemical performance while also displaying low batch to batch variability. Here we report the development of a printed sensor to monitor bone turnover. The absence of load bearing forces experienced in microgravity causes a reduction of overall bone mass and results in the development of space osteopenia/osteoporosis.(1,2) Our approach to identify space osteopenia/osteoporosis is to monitor the change in bone mass indirectly through an excreted biomarker of bone remodeling, amino-terminal collagen crosslinks (NTX). Antibodies specific to NTX are added to the sensor’s electrode ink and applied during the manufacturing process. NTX is measured from a urine sample by changes in voltammetry and electrochemical impedance as it binds to the antibody modified electrode surface. The measurement is rapid, quantitative and requires only small handheld electronics to perform the measurement. By this process, ground and flight physicians will receive frequent and real-time insight into the development of space osteopenia/osteoporosis to guide appropriate countermeasures. REFERENCES [1] Nabavi, N. et al (2011) Bone 49, 965-974. [2] Tamma, R. et al (2009) FASEB J 23, 2549-2554.

in-space manufacturing↗
NASA NTRSDate not supplied

Urine Concentration of Cartilage Degradation Marker CTX-II is Increased After Six Months on the ISS

Mechanical and gravitation load are both important regulators of articular cartilage metabolism. Immobilization and the absence of gravity likely change tissue morphology and characteristics that can result in atrophy and softening of cartilage. Type II collagen is the most abundant cartilage matrix protein and assessing the urinary excretion of crosslinked C-telopeptide (uCTX-II) provides an index of total type II collagen degradation. We hypothesized that reduced mechanical and gravitational loading during a 4 – 6 months International Space Station (ISS) mission will result in increased uCTX-II levels indicating cartilage degradation in healthy individuals.

Nadja Djalal↗
NASA NTRSDate not supplied

Urine Concentration of Cartilage Degradation Marker CTX-II is Sensitive to Microgravity

Mechanical and gravitation load are both important regulators of articular cartilage metabolism. Immobilization and the absence of gravity likely change tissue characteristics that can result in atrophy and softening of cartilage. Type II collagen is the most abundant cartilage matrix protein. Assessing urinary excretion of crosslinked C-telopeptide (uCTX-II) provides an index of total type II collagen degradation. We hypothesized that reduced mechanical and gravitational loading during a 4 – 6 months International Space Station (ISS) mission will result in increased uCTX-II levels.

Anna-maria Liphardt↗
NASA NTRS2022

Numerical Characterization of Astronaut CaOx Renal Stone Incidence Rates to Quantify In-flight and Post-flight Relative Risk

Changes in urine chemistry potentially alter the risk of renal stone formation in astronauts. Quantifying spaceflight renal stone incidence risk compared to pre-flight levels remains a significant challenge for assessing the appropriate vehicle, mission, and countermeasure design. A computational biochemistry model representing CaOx crystal precipitation, growth, and agglomeration is combined with a probabilistic analysis to predict the in- and post-flight CaOx renal stone incidence risk ratio (IRR) relative to pre-flight values using 1517 astronaut 24-hour urine chemistries. Our simulations predict that in-flight fluid intake alone would need to increase from current prescriptions of 2.0 - 2.5 L/day to approximately 3.2 L/day to approach CaOx IRR of the pre-flight population. Bone protective interventions would reduce CaOx risk to pre-flight levels if Ca excretion alone is reduced to < 150 mg/day or if current levels are diminished to 190mg/day in combination with increasing fluid intake to 2.5 - 2.7 L/day. This analysis provides a quantitative risk assessment that can influence the critical balance between engineering and astronaut health requirements.

renal stones↗
NASA NTRS2024

Evidence Report: Risk of Renal Stone Formation

Kidney stone formation and passage has the potential to greatly impact mission success and crewmember health, especially for long-duration missions. Alterations in hydration state (relative dehydration), spaceflight-induced changes in urine biochemistry (urine super-saturation), and bone metabolism (increased calcium excretion) during exposure to microgravity may increase the risk of kidney stone formation. There are possible countermeasures and treatments available that are used terrestrially that may then be applied to spaceflight. Directed Acyclic Graphs (DAGs) are used throughout this document to communicate spaceflight conditions that may lead to renal stone formation, the countermeasures that may be used to prevent their formation, and possible treatment modalities. The DAGs are sorted by strength of evidence, according to Table 6. Additionally, for the full Renal Stone Evidence Report Content: Directed Acyclic Graphs and Evidence Report, please see Appendix A, Expanded Directed Acyclic Graphs (DAGs) and Evidence. Additionally, a proposed Concept of Operations for the Prevention, Diagnosis, and Treatment of Renal Stones for a Mars Mission was created in conjunction with and to complement this Evidence Report update. Please see Appendix B, Proposed Expanded Concept of Operations for the Prevention, Diagnosis and Treatment of Renal Stones for Mars Missions, for the full report. Areas in the following Evidence Report will be cross-linked to scenarios from the Concept of Operations.

Emily Stratton↗