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An Automated Analytical Electrophoresis Apparatus (AAEA) was designed, developed, assembled, and preliminarily tested. The AAEA was demonstrated to be a feasible apparatus for automatically acquiring, displaying, and storing (and eventually analyzing) electrophoresis mobility data from living blood cells. The apparatus and the operation of its major assemblies are described in detail.
Eight human volunteers, individually studied in a hyperbaric chamber, breathed: (1) air at 1 ATA; (2) 80% argon and 20% oxygen at 1 ATA for 30 min; (3) air at 1 ATA for 30 min; (4) 100% O2 at 1 ATA for 30 min; (5) air at 1 ATA for 30 min; (6) 100% O2 at 2 ATA for 60 min; and (7) 80% argon and 20% oxygen at 1 ATA for 30 min. Oxygen, carbon dioxide, nitrogen, and argon tensions were measured in muscle and subcutaneous tissue by mass spectroscopic analyses. Venous blood obtained at regular intervals was analyzed for coagulation and fibrinolytic factors. Inert gas narcosis was not observed. After breathing argon for 30 min, muscle argon tensions were almost three times the subcutaneous tensions. Argon wash-in mirrored nitrogen wash-out. Argon wash-in and wash-out had no effect on tissue PO2 or PCO2. Coagulation and fibrinolytic changes usually associated with vascular bubbles were absent.
Ground based and in flight research has shown that humans, under conditions of microgravity, sustain a loss of lean body tissue (protein) and changes in several biological processes including, reductions in red blood cell mass, and neurotransmitters. The maintenance of muscle mass, the major component of lean body mass, is required to meet the needs of space station EVAs. Central to the biosynthesis of amino acids, the building blocks of protein, is pyridoxine (vitamin B-6). Muscle mass integrity requires the availability of vitamin B-6 for protein metabolism and neurotransmitter synthesis. Furthermore, the formation of red blood cells require pyridoxine as a cofactor in the biosynthesis of hemoglobin, a protein that carries oxygen to tissues. In its active form, pyridoxal-5'-phosphate (PLP), vitamin B-6 serves as a link between amino acid and carbohydrate metabolism through intermediates of glycolysis and the tricarboxylic acid cycle. In addition to its role in energy metabolism, PLP is involved in the biosynthesis of hemoglobin and neurotransmitter which are necessary for neurological functions. Alterations in pyridoxine metabolism may affect countermeasures designed to overcome some of these biochemical changes. The focus of this research is to determine the effects of microgravity on the metabolic utilization of vitamin B-6, integrating nutrition as an integral component of the countermeasure (exercise) to maintain lean body mass and muscle strength. The objectives are: 1) to determine whether microgravity effects the metabolic utilization of pyridoxine and 2) to quantitate changes in B-6 vitamer distribution in tissue and excreta relative to loss of lean body tissue. The rationale for this study encompasses the unique challenge to control biochemical mechanisms effected during space travel and the significance of pyridoxine to maintain and counter muscle integrity for EVA activities. This experiment will begin to elucidate the importance of biochemical interactions between micronutrients and the homeostasis condition of biological processes in the space environment. To address this research topic a simulated microgravity model has been developed. The experiment uses radioisotopically labelled pyridoxine administered as an oral dose to rats which are maintained by tail suspension to simulate a microgravity environment. At the termination of the study, liver, muscle, blood and urine are collected and analyzed by reverse phase high pressure liquid chromatography to determine the quantity and distribution of the B-6 vitamers in tissue and excreta relative to lean body tissue loss. Earlier studies, published by this investigator, have shown that differences in vitamer distribution among samples from experimental versus control subjects indicate changes in metabolic utilization and storage of vitamin B-6.
The quantitative comparison of the chemical concentration inside the body as the result of a dermal exposure versus an inhalation exposure is useful for assessing human health risks and deciding on an appropriate protective posture. In order to describe the relationship between dermal and inhalation routes of exposure, a variety of organic chemicals were evaluated. The types of chemicals chosen for the study were halogenated hydrocarbons, aromatic compounds, non-polar hydrocarbons and inhalation anesthetics. Both dermal and inhalation exposures were conducted in rats and the chemicals were in the form of vapors. Prior to the dermal exposure, rat fur was closely clipped and during the exposure rats were provided fresh breathing air through latex masks. Blood samples were taken during 4-hour exposures and analyzed for the chemical of interest. A physiologically based pharmacokinetic model was used to predict permeability constants (cm/hr) consistent with the observed blood concentrations of the chemical. The ratio of dermal exposure to inhalation exposure required to achieve the same internal dose of chemical was calculated for each test chemical. The calculated ratio in humans ranged from 18 for styrene to 1180 for isoflurane. This methodology can be used to estimate the dermal exposure required to reach the internal dose achieved by a specific inhalation exposure. Such extrapolation is important since allowable exposure standards are often set for inhalation exposures, but occupational exposures may be dermal.
During long duration space missions, astronauts experience immune system dysregulation [1], and white blood cell (WBC) count can give vital information about the body’s immune response. The ability to measure WBC count is currently an unmet need on the International Space Station (ISS) and for future exploration missions. To address this need, the Human Research Program’s (HRP) Exploration Medical Capability (ExMC) Element, along with the Research Operations and Integration (ROI) Element and the NASA Johnson Space Center Immunology Lab, flew HemoCue®, a commercial-off-the-shelf analyzer with the ability to measure whole blood WBC count with 5-part differential to ISS in December 2020.
We evaluated the use of a small, fiber optic sensor to measure pH, PCO2 and PO2 from forearm muscle interstitial fluid (IF) during handgrip dynamometry. PURPOSE: Compare pH, PCO2 and PO2 values obtained from venous blood with those from the IF of the flexor digitorum superficialis (FDS) during three levels of exercise intensity. METHODS: Six subjects (5M/1F), average age 29+/-5 yrs, participated in the study. A venous catheter was placed in the retrograde direction in the antecubital space and a fiber optic sensor (Paratrend, Diametrics Medical, Inc.) was placed through a 22 G catheter into the FDS muscle under ultrasound guidance. After a 45 min rest period, subjects performed three 5-min bouts of repetitive handgrip exercise (2s contraction/1 s relaxation) at attempted levels of 15%, 30% and 45% of maximal voluntary contraction. The order of the exercise bouts was random with the second and third bouts started after blood lactate had returned to baseline. Venous blood was sampled every minute during exercise and analyzed with an I-Stat CG-4+ cartridge, while IF fiber optic sensor measurements were obtained every 2 s. Change from pre-exercise baseline to end of exercise was computed for pH, PCO2 and PO2. Blood and IF values were compared with a paired t-test. RESULTS: Baseline values for pH, PCO2 and PO2 were 7.37+/-0.02, 46+/-4 mm Hg, and 36+/-6 mm Hg respectively in blood and 7.39+/-0.02, 44+/-6 mm Hg, and 35+/-14 mm Hg in IF. Average changes over all exercise levels are noted in the Table below. For each parameter the exercise-induced change was at least twice as great in IF as in blood. In blood and IF, pH and PCO2 increases were directly related to exercise intensity. Change in venous PO2 was unrelated to exercise intensity, while IF PO2 decreased with increases in exercise intensity. CONCLUSIONS: Measurement of IF pH, PCO2 and PO2 is more sensitive to exercise intensity than measurement of the same parameters in venous blood and provides continuous assessment during and after exercise.
Wastewater treatment wetlands are cost-effective strategies for remediating trace metals in industrial effluent. However, biogeochemical exchange between wastewater treatment wetlands and adjacent environments provides opportunities for trace metals to cycle in surrounding ecosystems. The transfer of trace metals to wildlife inhabiting treatment wetlands must be considered when evaluating wetland success. Using passerine birds as bioindicators, we conducted a multi-tissue analysis to investigate the mobilization of zinc, copper, and lead derived from wastewater to terrestrial wildlife in treatment wetlands and surrounding habitat. In addition, we evaluate the strength of relationships between metal concentrations in non-lethal (blood and feathers) and lethal (muscle and liver) sample types for estimation of toxicity risk. From July 2020 to August 2021, 177 passerines of seven species were captured at two wetlands constructed to treat industrial wastewater and two reference wetlands in the coastal plain of South Carolina. Feather, blood, liver, and muscle samples from each bird were analyzed for fourteen metals using inductively coupled plasma mass spectrometry and direct mercury analysis. Passerines inhabiting wastewater treatment wetlands accumulated higher concentrations of zinc in liver, copper in blood, and lead in feathers than passerines in reference wetlands, but neither blood nor feather concentrations were correlated with internal tissue concentrations. Of all the detected metals, only mercury in the blood showed a strong predictive relationship with mercury in internal tissues. This study indicates that trace metals derived from wastewater are bioavailable and exported to terrestrial wildlife and that passerine biomonitoring is a valuable tool for assessing metal transfer from treatment wetlands. Furthermore, regular blood sampling can reveal proximate trace metal exposure but cannot predict internal body burdens for most metals.
The purpose of this study was to determine if fluid-electrolyte, renal, hormonal, and cardiovascular responses during and after multi-hour water immersion were associated with aerobic training. Additionally, we compared these responses in those who trained in a hypogravic versus a 1-g environment. Seventeen men comprised three similarly aged groups: six long-distance runners, five competitive swimmers, and six untrained control subjects. Each subject underwent 5 h of immersion in water [mean (SE)] 36.0 (0.5) degrees C to the neck. Immediately before and at each hour of immersion, blood and urine samples were collected and analyzed for sodium (Na), potassium, osmolality, and creatinine (Cr). Plasma antidiuretic hormone and aldosterone were also measured. Hematocrits were used to calculate relative changes in plasma volume (% delta Vpl). Heart rate response to submaximal cycle ergometer exercise (35% peak oxygen uptake) was measured before and after water immersion. Water immersion induced significant increases in urine flow, Na clearance (CNa), and a 3-5% decrease in Vpl. Urine flow during immersion was greater (P < 0.05) in runners [2.4 (0.4) ml.min-1] compared to controls [1.3 (0.1) ml.min-1]. However, % delta Vpl, CCr, CNa and CH2O during immersion were not different (P > 0.05) between runners, swimmers, and controls. After 5 h of immersion, there was an increase (P < 0.05) in submaximal exercise heart rate of 9 (3) and 10 (3) beats.min-1 in both runners and controls, respectively, but no change (P > 0.05) was observed in swimmers.(ABSTRACT TRUNCATED AT 250 WORDS).
The erythropoiesis modeling performed in support of the Body Fluid and Blood Volume Regulation tasks is described. The mathematical formulation of the species independent model, the solutions to the steady state and dynamic versions of the model, and the individual species specific models for the human, squirrel monkey, rat and mouse are outlined. A detailed sensitivity analysis of the species independent model response to parameter changes and how those responses change from species to species is presented. The species to species response to a series of simulated stresses directly related to blood volume regulation during space flight is analyzed.
Cytotoxic activity of non-major histocompatibility complex-restricted (CD56+) (NMHC) killer cells and cell surface marker expression of peripheral blood mononuclear cells were determined before and after spaceflight. Ten astronauts (9 men, 1 woman) from two space shuttle missions (9- and 10-day duration) participated in the study. Blood samples were collected 10 days before launch, within 3 h after landing, and 3 days after landing. All peripheral blood mononuclear cell preparations were cryopreserved and analyzed simultaneously in a 4-h cytotoxicity (51)Cr release assay using K562 target cells. NMHC killer cell lytic activity was normalized per 1,000 CD56+ cells. When all 10 subjects were considered as one study group, NMHC killer cell numbers did not change significantly during the three sampling periods, but at landing lytic activity had decreased by approximately 40% (P < 0.05) from preflight values. Nine of ten astronauts had decreased lytic activity immediately after flight. NMHC killer cell cytotoxicity of only three astronauts returned toward preflight values by 3 days after landing. Consistent with decreased NMHC killer cell cytotoxicity, urinary cortisol significantly increased after landing compared with preflight levels. Plasma cortisol and ACTH levels at landing were not significantly different from preflight values. No correlation of changes in NMHC killer cell function or hormone levels with factors such as age, gender, mission, or spaceflight experience was found. After landing, expression of the major lymphocyte surface markers (CD3, CD4, CD8, CD14, CD16, CD56), as determined by flow cytometric analysis, did not show any consistent changes from measurements made before flight.
Space exploration class missions, such as a mission to Mars, will require optimization of human performance, adaptability, and resilience. This NASA Specialized Center of Research (NSCOR) utilizes the NIMH Research Domain Criteria (RDoC) framework to identify biological and behavioral markers of individual social adaptation and emotional resilience (as well as vulnerability) to spaceflight-relevant stressors such as living in extended isolation. The overarching goal of this NSCOR is to obtain novel information to help identify biomarkers of individuals who are resilient and/or adaptable to the stressors of isolated, confined, and controlled (ICC) and isolated, confined, and extreme (ICE) environments.A total of N=90 healthy adult astronaut surrogates are being studied in three spaceflight-analog environments: (1) n=40 healthy adults in the Isolation and Confinement Analog Research Unit (ICARUS), an ICC at the University of Pennsylvania, during 7-day missions, for a target total of 280 subject days; (2) n=32 healthy adult astronaut surrogates studied in NASA’s Human Exploration Research Analog (HERA), an ICC at Johnson Space Center during 45-day missions, for a target total of 2,112 subject days; and (3) n=18 healthy adults in the Alfred-Wegener-Institute’s Neumayer Station III, an ICE in Antarctica, during 14-month missions, for a target total of 7,560 subject days. Dr. Nindl’s Laboratory at the University of Pittsburgh is analyzing a priori selected protein biomarkers in blood, saliva, and urine. Complementary rodent models of exposure to early life stressors, confinement, and isolation are being evaluated at Dr. Hensch’s Laboratory to further validate the neurobehavioral and biological findings from the human studies.Given the inconsistency and varied definition of resilience/adaptation in the scientific literature, the NSCOR team developed a composite resilience/adaptation measure that reflects the most relevant outcomes to resilience/adaptation across psychosocial and neurobehavioral functions, as well as neurocognitive and spaceflight-relevant operational performance. To achieve this, group consensus was attained from subject matter experts to produce a rank-order of importance for each input variable. The final resilience/adaptation score included 36 variables that were collected across spaceflight analogs. As of 10/1/2021, the NSCOR project acquired data on n=27 subjects at ICARUS, n=16 at HERA, and n=18 at Neumayer. The COVID-19 pandemic delayed data acquisition at ICARUS and HERA.Among subjects studied to date, 99% of neural and neurobehavioral data (e.g., neuroimaging for structure and function, behavioral measures) as well as blood, saliva, and urine for biochemical assays have been acquired. For rodent models, Dr. Hensch’s laboratory has established biochemical and behavioral parameters reflecting confinement stress in social networks of mice for comparison to stress responses in the human spaceflight analog environments.Group social behaviors were measured with a Social Network Analysis (SNA) approach to define objective parameters associated with sociability and its plasticity by sex. This analytic approach may help identify a network of individuals who are more effective teammates or more likely to generate new social relationships. Data acquisition, biomarker assessment, and data quality control will continue through September 2022.
(1) Background: After spending a year wintering in Antarctica, individual expedition members have reported increased or even new allergic reactions to environmental allergens after their return. (2) Methods: Blood samples from five overwintering crews were analyzed using the chip based multiplex ALEX Allergy Explorer (MacroArray Diagnostics GmbH, Austria). (3) Results: About one third of the 39 participants displayed specific IgEs against pollen. In most individuals, kinetics showed a reduction in the specific IgE at the time about nine months after deployment to Antarctica. Five participants had the highest specific IgE levels after returning to the “normal” world. The examination of the specific IgE relative to house dust mites and storage mites showed different kinetics. Six out of 10 had the highest specific IgE concentrations at the inner Antarctic measurement time point. These data corresponded well to the general situation in the stations. At the stations themselves, there were almost no pollen particle load, especially at Concordia. (4) Conclusions: Antarctic long-term confinement can induce an altered immune function, which is in some individuals pronounced after return to the familiar allergen environment. Future prospective studies in larger cohorts are needed to further specify these first results.
Study of mammalian blood to determine glucose levels and the effects of polycythemia and hyperoxia
BACKGROUND: Despite great progress in reducing environmental lead (Pb) levels, many children in the United States are still being exposed. OBJECTIVE: Our aim was to develop a generalizable approach for systematically identifying, verifying, and analyzing locations with high prevalence of children’s elevated blood Pb levels (EBLLs) and to assess available Pb models/indices as surrogates, using a Michigan case study. METHODS: We obtained ~1:9 million BLL test results of children <6 years of age in Michigan from 2006–2016; we then evaluated them for data representativeness by comparing two percentage EBLL (%EBLL) rates (number of children tested with EBLL divided by both number of children tested and total population). We analyzed %EBLLs across census tracts over three time periods and between two EBLL reference values (≥5 vs. ≥10 μg/dL) to evaluate consistency. Locations with high %EBLLs were identified by a top 20 percentile method and a Getis-Ord Gi* geospatial cluster “hotspot” analysis. For the locations identified, we analyzed convergences with three available Pb exposure models/indices based on old housing and sociodemographics. RESULTS: Analyses of 2014–2016 %EBLL data identified 11 Michigan locations via cluster analysis and 80 additional locations via the top 20 percentile method and their associated census tracts. Data representativeness and consistency were supported by a 0.93 correlation coefficient between the two EBLL rates over 11 y, and a Kappa score of ~0:8 of %EBLL hotspots across the time periods (2014–2016) and reference values. Many EBLL hotspot locations converge with current Pb exposure models/indices; others diverge, suggesting additional Pb sources for targeted interventions. DISCUSSION: This analysis confirmed known Pb hotspot locations and revealed new ones at a finer geographic resolution than previously available, using advanced geospatial statistical methods and mapping/visualization. It also assessed the utility of surrogates in the absence of blood Pb data. This approach could be applied to other states to inform Pb mitigation and prevention efforts. https://doi.org/10.1289/EHP9705
A description is given of a self-contained automated primate research laboratory to study the effects of weightlessness on subhuman primates. Physiological parameters such as hemodynamics, respiration, blood constituents, waste, and diet and nutrition are analyzed for abnormalities in the simulated space environment. The Southeast Asian pig-tailed monkey (Macaca nemistrina) was selected for the experiments owing to its relative intelligence and learning capacity. The objective of the program is to demonstrate the feasibility of a man-tended primate space flight experiment.
Background: Pig-tailed macaques (PTMs) are commonly used as preclinical models to assess antiretroviral drugs for HIV prevention research. Drug toxicities and disease pathologies are often preceded by changes in blood hematology. To better assess the safety profile of pharmaceuticals, we defined normal ranges of hematological values in PTMs using an Isolation Forest (iForest) algorithm. Methods: Eighteen female PTMs were evaluated. Blood was collected 1–24 times per animal for a total of 159 samples. Complete blood counts were performed, and iForest was used to analyze the hematology data to detect outliers. Results: Median, IQR, and ranges were calculated for 13 hematology parameters. From all samples, 22 outliers were detected. These outliers were excluded from the reference index. Conclusions: Using iForest, we defined a normal range for hematology parameters in female PTMs. This reference index can be a valuable tool for future studies evaluating drug toxicities in PTMs.
During spaceflight, astronauts are exposed to multiple unique environmental factors, particularly microgravity and ionizing radiation, that can cause a range of harmful health consequences. Over the past decades, increasing evidence demonstrates that the space environment can induce changes in gene expression and RNA processing. Long non-coding RNA (lncRNA) represent an emerging area of focus in molecular biology as they modulate chromatin structure and function, the transcription of neighboring genes, and affect RNA splicing, stability, and translation. They have been implicated in cancer development and associated with diverse cardiovascular conditions and associated risk factors. However, their role on astronauts’ health after spaceflight remains poorly understood. In this perspective article, we provide new insights into the potential role of exosomal lncRNA after spaceflight. We analyzed the transcriptional profile of exosomes isolated from peripheral blood plasma of three astronauts who flew on various Shuttle missions between 1998–2001 by RNA-sequencing. Computational analysis of the transcriptome of these exosomes identified 27 differentially expressed lncRNAs with a Log 2 fold change, with molecular, cellular, and clinical implications.
The cause of the red cell mass (RCM) deficit, which occurs in rats during suspenion, is investigated. The experimental conditions and procedures, in which male Sprague-Dawley rats are subjected to antiorthostatic hyypokinetic/hypodynamia and changes in RCM are monitored, are described. The influences of stress, reduced food and water consumption, and antiorhostatic posture on RCM are analyzed. Changes in body weight, RCM, radioiron incorporation, red blood cells (RBC), and reticulocytes, for the rats after head-down suspension are graphically presented; only the changes in RBC are related to the antiorthostatic posture. The data reveal that anemia is primarily caused by reduced food and water consumption and secondly by restricted movements.