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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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Microscopic and histochemical evaluations of human embrionic lung cells after exposure to zero-gravity are reported. Growth curves, DNA microspectrophotometry, phase microscopy, and ultrastructural studies of fixed cells revealed no effects on the cultures. Minor unexplained differences have been found in biochemical constituents of the samples.
Blood samples from Spacelab crewmembers were studied for possible environment effects on red cell components. Analysis involved peroxidation of red cell lipids, enzymes of red cell metabolism, and levels of 2,3-diphosphoglyceric acid and adenosine triphosphate. Results show that there is no evidence of lipid peroxidation, that biochemical effect known to be associated with irreversible red cell damage. Changes observed in glycolytic intermediates and enzymes cannot be directly implicated as indicating evidence of red cell damage.
The characteristics and efficiencies of biochemical reactions involving nucleoside 5'-diphosphates and -triphosphates (important substrates of RNA and DNA synthesis) under conditions corresponding to the primitive prebiotic earth are investigated. Urea catalysis of the formation of linear inorganic polyphosphates and metal ions promoting the reactions are discussed. Linear polyphosphate was incubated with Mg(++) in the presence of a nucleoside 5'-phosphate, to yield nucleoside 5'-polyphosphates when products are dried, while Mg(++) prompts depolymerization to trimetaphosphate in aqueous solutions. Plausible biogenetic pathways are examined.
The subfornical organ (SFO) is a circumventricular structure located at the junction of the lamina terminalis and the tela choroidea of the third cerebral ventricle. SFO is histologically regarded as a neurosecretory structure, although the physiological effects or biochemical nature of such secretions are not yet ascertained. Results are presented for an experimental study designed to determine whether SFO extracts alter parameters associated with salt-water balance in the rat. The data obtained support the conclusion that SFO contains some water-soluble substance(s), easily released by incubation, dialyzable and heat stable, which influences the salt-water balance after injection into ventricular cerebrospinal fluid. Whether other brain tissues or plasma contains the same or similar material is not yet convincingly established. The observation that one or more active constituents are easily released from SFO upon incubation in potassium-enriched medium may be of value.
Latex particles with attached antibodies have potential biochemical and environmental applications. Human red blood cells and lymphocytes have been labeled with fluorescent microspheres by either direct or indirect immunological technique. Immunolatex spheres can also be used for detecting and localizing specific cell surface receptors. Hormones and toxins may also be bondable.
Bed rest conditions evaluated varied in the longitudinal axis of the body, perpendicular to the vector gravitational forces, and the cranial portion of the body inclined from the horizontal. The duration of bed rest fluctuated in various experiments from 30 to 182 days. The state of muscle and neuromuscular system was judged on the basis of the recording of various functional indices, as well as by certain results of morphological and biochemical studies and data from the study of motor functions.
Academician O. Gazenko, Chief of the Institute of Biomedical Problems, USSR Ministry of Public Health, reviewed the short but intense history of Soviet research in space biology and medicine. The solid academic approach of the Soviet Academy of Sciences in giving a good start at the very beginning of the space age is stressed and key people and institutions who initiated these studies are named. The basic feature of the first period of space biology is seen as the search for answers to a few fundamental questions of survival in space. It is pointed out that the initiated investigations were replaced by refined, in-depth studies of the biological, biophysical, and biochemical processes in human organism in the space environment and the search for methods which should enable cosmonaut crews to live in space for several years during interplanetary journeys. Discussing the typical problems of this effort, Gazenko each time showed how they benefit medical science and practice in general.
Systematic laboratory procedures compiled as an outgrowth of a joint U.S./U.S.S.R. microbiological-immunological experiment performed during the Apollo-Soyuz Test Project space flight are presented. Included are mutually compatible methods for the identification of aerobic and microaerophilic bacteria, yeast and yeastlike microorganisms, and filamentous fungi; methods for the bacteriophage typing of Staphylococcus aureus; and methods for determining the sensitivity of S. aureus to antibiotics. Immunological methods using blood and immunological and biochemical methods using salivary parotid fluid are also described. Formulas for media and laboratory reagents used are listed.
A large scale field experiment, which was arranged in support of the Nimbus G - Coastal Zone Color Scanner (CZCS) project was studied. The experiment was to provide three air and two shipborne platforms simultaneously to members of the Nimbus G Experiment Team (NET) and to other scientists in order to collect data from common test sites. Besides establishing fundamental relations between the light in the sea and the biochemical properties of water, the data will be used mainly for the development of algorithms during the prelaunch phase of Nimbus G.
Brown adipose tissue serves as a model system for nonshivering thermogenesis (NST) since a) it has as a primary physiological function the conversion of chemical energy to heat; and b) preliminary data from other tissues involved in NST (e.g., muscle) indicate that parallel mechanisms may be involved. Now that biochemical pathways have been proposed for brown fat thermogenesis, cellular models consistent with a thermodynamic representation can be formulated. Stated concisely, the thermogenic mechanism in a brown fat cell can be considered as an energy converter involving a sequence of cellular events controlled by signals over the autonomic nervous system. A thermodynamic description for NST is developed in terms of a nonisothermal system under steady-state conditions using network thermodynamics. Pathways simulated include mitochondrial ATP synthesis, a Na+/K+ membrane pump, and ionic diffusion through the adipocyte membrane.
Indirect method for detection of microbial growth utilizes flow of charged particles across barrier that physically separated growing cells from electrodes and measures resulting difference in potential between two platinum electrodes. Technique allows simplified noncontact monitoring of all growth in highly infectious cultures or in critical biochemical studies.
The general objective of the research was to provide the space and life sciences directorate with an improved biostereometric measurement capability. This objective was determined from the usefulness of stereophotogrametric techniques developed during the Apollo and Skylab Missions to measure body conformation, surface area, volume and relative density of astronauts. These noninvasive anthropometric measurements provided invaluable data concerning the physiological, biochemical and nutritional effects of the space environment upon the human body. The indirect nature of the technique has many advantages over other methods, and has a potential for many other applications. The stereophotographs contain an enormous amount of data which can be later reexamined should the need arise.
The relationship between calcium and strontium in bone metabolism is described. Whole body comparisons in the form of balance studies, plasma kinetics, and biochemical bone differences are briefly reviewed. The value of strontium as a qualitative calcium mimetic is established. A procedure of strontium deposition in the bones is presented as a means to study postflight bone rebuilding and to locate areas of inflight demineralization.
It is attempted to show that the use of heavy water (D2O) as starting cushion for the cells combines the advantages of the required density difference, with no lasting biochemical or physiochemical influence on the cells. Phosphate buffers of low ionic strength were prepared in distilled water or heavy water. A vertical starch gel electrophoresis was used to support a cylindrical polystyrene electrophoresis tube used for lymphocyte separations, 25 cm in length and 0.75 cm I.D., prepared from a 10 ml disposable pipet. Erythrocyte separations were carried out in a jacketed rectangular plexiglas chamber. It is pointed out that the described preparative D2O gradient electrophoresis method cannot be readily used for the measurement of electrophoretic mobilities for analytical purposes. However, for the preparative separation of cells with only slightly different electrokinetic properties the method appears promising, simple, and entirely inocuous to the cells.
The paper examines RNA-ribosomal changes observed in protozoa and fixed postmitotic cells, as well as the characteristics of intermitotic cells. Attention is given to a discussion of the implications of the reported ribosomal changes as to the senescent deterioration of protein synthesis and physiological functions. A survey of the literature suggests that, while the data on ribosomal change in dividing cells both in vivo and in vitro are inconclusive, there is strong histological and biochemical evidence in favor of some degree of quantitative ribosomal loss in fixed postmitotic cells. Since these decreases in ribosomes are demonstrated in differential cells from nematodes, insects and mammals, they may represent a universal manifestation of cytoplasmic senescence in certain types of fixed postmitotic animal cells. The observed variability in ribosomal loss for cells belonging to the same type suggests that this involution phenomenon is rather related to the wear and tear suffered by a particular cell.
The Arabidopsis thaliana plant species is tested to determine how a higher plant will develop from seed to maturity when deprived of all gravitational information that it might use to control its growth. Experimental results show that Arabidopsis seedlings can develop to maturity by means of a light-dependent but CO2-independent metabolism that feeds on organic compounds derived from the culture medium. This process is identified as photoassimilation. The ability of a higher plant to nourish itself by photoassimilation and thereby to survive in a heremetically sealed chamber of small dimensions is more than a biochemical curiosity. It allows the botanical investigator to design a culture system convenient for space-flight applications, which ensures isolation of each test plant from the gaseous environment of the spacecraft.
Physiological, biochemical and morphological studies made on the Cosmos-782 biosatellite are presented. Rats, which were exposed on the biosatellite for 19.5 days, were examined immediately after completion of the flight and also during the 25 day period of readaptation to earth's conditions. The effect of factors of space flight, primarily weightlessness, on the organism was investigated for all systems of the body.
A discussion of freshwater and marine systems is presented including areas of the classification of lakes, identification and quantification of major functional groups of phytoplankton, sources and sinks of biochemical factors, and temporal and regional variability of surface features. Atmospheric processes linked to hydrospheric process through the transfer of matter via aerosols and gases are discussed. Particle fluxes to the aquatic environment and global geochemical problems are examined.