Search NASA⌕ Search

SEARCH · Search NASA

Results for “body weight”

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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Aristolochic acid-induced genotoxicity and toxicogenomic changes in rodents

Aristolochic acid (AA) is a group of structurally related nitrophenanthrene carboxylic acids found in many plants that are widely used by many cultures as traditional herbal medicines. AA is a causative agent for Chinese herbs nephropathy, a term replaced later by AA nephropathy. Evidence indicates that AA is nephrotoxic, genotoxic, and carcinogenic in humans; and it also induces tumors in the forestomach, kidney, renal pelvis, urinary bladder, and lung of rats and mice. Therefore, plants containing AA have been classified as carcinogenic to humans (Group 1) by the International Agency for Research on Cancer. In our laboratories, we have conducted a series of genotoxicity and toxicogenomic studies in the rats exposed to AA of 0.1–10 mg/kg for 12 weeks. Our results demonstrated that AA treatments induced DNA adducts and mutations in the kidney, liver, and spleen of rats, as well as significant alteration of gene expression in both its target and nontarget tissues. AA treatments altered mutagenesis- or carcinogenesis-related microRNA expression in rat kidney and resulted in significant changes in protein expression profiling. We also applied benchmark dose (BMD) modeling to the 3-month AA-induced genotoxicity data. The obtained BMDL10 (the lower 95% confidence interval of the BMD 10 that is a 10% increase over the background level) for AA-induced mutations in the kidney of rats was about 7 μg/kg body weight per day. This review constitutes an overview of our investigations on AA-induced genotoxicity and toxicogenomic changes including gene expression, microRNA expression, and proteomics; and presents updated information focused on AA-induced genotoxicity in rodents.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1971

To develop a spectral analyzer for physiological and medical use

Scientific requirements necessary to develop a spectral analyzer for monitoring mammalian subjects, are discussed. The analyzer measures dynamic or time dependent data as a measure of the subjects operating status. Measurable data include metabolic rate, body temperature, and blood constituents like glucose, oxygen, and carbon dioxide, and lactic acid. Metabolic cycles were found with periodicities in the range of minutes and hours; longer cycles in body weight (3 1/2 days and 60 days), indicative of metabolic processes, were also found.

Iberall, A.↗
NASA NTRS1972

Seventeen Ketogenic steroids excretion in crewmen in a 90-day manned test of an advanced regenerative life support system

Seventeen KGS (17-Ketogenic steroids) and Na/K were determined in 19 urine specimens collected by each of 4 crewmen during the 90-day test. The specimens represented 10% aliquots of 24-hour collections stored frozen onboard the simulator until passthrough. Electrolytes were analyzed immediately after sample passthrough while the steroids were determined post-test on aliquots of the original sample held at 203 K. Steroid data was corrected for body weight and also for analytical variation in the laboratory urine pool control. Long-term nonspecific responses to low-level stress appear to be reflected by the individual and group mean 17-KGS excretion patterns. The first 39 and the last 20 days of the test were significantly different--and presumably more stressful to the crew--than the period from days 39 to 67. Reduction of adrenocortical function during the mid-test phase is attributed to either an adaptation to chronic or intermittent stress or was the result of an actual reduction in the operational demands of the test during this time. Most remarkable of the metabolic findings is the prevalance of high Na/K ratios and an abrupt peak on day 74 for all 4 crewmen.

Myers, D. J.↗
NASA NTRS1971

Peripheral modifications to the central drive for sweating.

Three subjects performed from 15 to 20 bouts of 10-min bicycle ergometer exercise in a 26 C ambient. The procedure imposed a consistent pattern of internal (esophageal) temperature increase in the presence of a constant mean skin temperature. Body weight loss was continuously recorded and rate of evaporative loss due to sweating was calculated during each minute of exercise. It was confirmed that both local and total sweating are functions of internal temperature at a fixed constant mean skin temperature. In the presence of a constant central drive for sweating, the sweating response could be modified at the periphery according to the area-specific characteristics and/or by local temperature.

Nadel, E. R.↗
NASA NTRS1972

A common modality of action of simulated space stresses on the oxidative metabolism of ethylmorphine, aniline and p-nitroanisole by male rat liver.

High gravity, cold and starvation elicited similar responses in male Simonson rats. These responses included a decreased rate in body weight gain, increased metabolism of aniline and p-nitroanisole, and no consistent pattern of change in the metabolism of ethylmorphine. Cold and starvation increased the amount of hepatic cytochrome P-450, while hypobaric-hyperoxia caused no change in any of the parameters measured. When 1% acetone was given to the rats in their drinking water, the effects on drug metabolism were similar to those produced by food restriction in that the metabolism of aniline and p-nitroanisole was increased, and the metabolism of ethylmorphine unchanged. The type I binding spectrum of acetone suggests that it is either a substrate, inhibitor, or both for hepatitic oxidative enzymes.

Furner, R. L.↗
NASA NTRS1972

Bioastronautic aspects of Apollo biomedical operations.

Bioastronautic results of the 3105 man-hours of Apollo space flight. The absence of solar flare eliminated the radiation problem for Apollo, but for prolonged flight the problem has not been solved. Crews have adapted generally to weightlessness and used it to advantage. Body weight loss is noted, and it is only partly due to fluid loss. Sleep appears to be impaired. The preventive medicine program has been difficult to conduct but in the later flights it effectively reduced the incidence of upper respiratory and gastrointestinal infection. Motion sickness has been noted, but all astronauts adapted well. Cardiovascular deconditioning has been similar in degree and duration to that noted after the Gemini flights. The loss of red blood cell mass of Gemini was found only in Apollo 9, which was the only Apollo flight where the astronauts were exposed to pure oxygen at 5 psia for prolonged periods.

Humphreys, J. W., Jr.↗
NASA NTRS1972

The NASA-USPHS Health Evaluation and Enhancement Program

An exercise program was initiated to assess the feasibility of an on the job health evaluation and enhancement program, as well as to identify the factors which influenced volunteering, adherence, and effectiveness of the program. The program was utilized by 237 of the 998 eligible Federal employees, with a mean attendance of 1.3 days per week. Those who volunteered perceived a need for increased physical activity, felt they had sufficient time to participate, and derived subjective as well as objective benefits. Significant improvements were found in heart rate response to the standard exercise test, body weight, skinfold measurements, and triglycerides. A consistent relationship was found between subjectively reported effects of the program on work, health habits, and behavior, and improvement in cardiovascular function, based on treadmill performance. Numerous personal and programmatic factors influencing volunteering and participation were identified.

Durbeck, D. C.↗
NASA NTRS1972

The National Aeronautics and Space Administration-U.S. Public Health Service Health Evaluation and Enhancement Program - Summary of results.

An exercise program was initiated in a federal agency to assess the feasibility of such a program, and to identify the factors that influenced joining, adherence to, and effectiveness of the program. The program was utilized by 237 of the 998 eligible federal employees; mean attendance rate was 1.3 days/week. Those who volunteered perceived a need for increased physical activity, believed they had sufficient time to participate and derived subjective as well as objective benefits. Significant improvements were found in heart rate response to the standard exercise test, body weight, skinfold measurements and triglyceride levels.

Durbeck, D. C.↗
NASA NTRS1973

Helium-cold induced hypothermia in the white rat.

Hypothermia was induced in white rats by exposing them to low ambient temperatures (about 0 C) and a gaseous atmosphere of 80% helium and 20% oxygen (helox). Biological survival, in which revival from hypothermia to normothermia is achieved, and clinical survival, in which one or more functional attributes are monitored in the hypothermic animal until it dies, are examined. The helium-cold method appears to produce a hypothermic state in the rat quite similar to that resulting from such techniques as ice water immersion or hypercapnia + hypoxia. There is a direct relationship between body weight and percent survival. Despite the fact that they require a longer period to become hypothermic, the heavier animals are better able to survive.

Musacchia, X. J.↗
NASA NTRS1974

Ecological effects and environmental fate of solid rocket exhaust

Specific target processes were classified as to the chemical, chemical-physical, and biological reactions and toxic effects of solid rocket emissions within selected ecosystems at Kennedy Space Center. Exposure of Citris seedlings, English peas, and bush beans to SRM exhaust under laboratory conditions demonstrated reduced growth rates, but at very high concentrations. Field studies of natural plant populations in three diverse ecosystems failed to reveal any structural damage at the concentration levels tested. Background information on elemental composition of selected woody plants from two terrestrial ecosystems is reported. LD sub 50 for a native mouse (peromysous gossypinus) exposed to SRM exhaust was determined to be 50 ppm/g body weight. Results strongly indicate that other components of the SRM exhaust act synergically to enhance the toxic effects of HCl gas when inhaled. A brief summary is given regarding the work on SRM exhaust and its possible impact on hatchability of incubating bird eggs.

Nimmo, B.↗