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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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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Defining blood hematology reference values in female pig-tailed macaques ( Macaca nemestrina ) using the Isolation Forest algorithm

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.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

Deep learning applications in visual data for benign and malignant hematologic conditions: a systematic review and visual glossary

Deep learning (DL) is a subdomain of artificial intelligence algorithms capable of automatically evaluating subtle graphical features to make highly accurate predictions, which was recently popularized in multiple imaging-related tasks. Because of its capabilities to analyze medical imaging such as radiology scans and digitized pathology specimens, DL has significant clinical potential as a diagnostic or prognostic tool. Coupled with rapidly increasing quantities of digital medical data, numerous novel research questions and clinical applications of DL within medicine have already been explored. Similarly, DL research and applications within hematology are rapidly emerging, although these are still largely in their infancy. Given the exponential rise of DL research for hematologic conditions, it is essential for the practising hematologist to be familiar with the broad concepts and pitfalls related to these new computational techniques. This narrative review provides a visual glossary for key deep learning principles, as well as a systematic review of published investigations within malignant and non-malignant hematologic conditions, organized by the different phases of clinical care. In order to assist the unfamiliar reader, this review highlights key portions of current literature and summarizes important considerations for the critical understanding of deep learning development and implementations in clinical practice.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

Risk of hematological malignancies from CT radiation exposure in children, adolescents and young adults

Over one million European children undergo computed tomography (CT) scans annually. Although moderate- to high-dose ionizing radiation exposure is an established risk factor for hematological malignancies, risks at CT examination dose levels remain uncertain. Here we followed up a multinational cohort (EPI-CT) of 948,174 individuals who underwent CT examinations before age 22 years in nine European countries. Radiation doses to the active bone marrow were estimated on the basis of body part scanned, patient characteristics, time period and inferred CT technical parameters. We found an association between cumulative dose and risk of all hematological malignancies, with an excess relative risk of 1.96 (95% confidence interval 1.10 to 3.12) per 100 mGy (790 cases). Similar estimates were obtained for lymphoid and myeloid malignancies. Results suggest that for every 10,000 children examined today (mean dose 8 mGy), 1–2 persons are expected to develop a hematological malignancy attributable to radiation exposure in the subsequent 12 years. Our results strengthen the body of evidence of increased cancer risk at low radiation doses and highlight the need for continued justification of pediatric CT examinations and optimization of doses.

60 APPLIED LIFE SCIENCES↗
NASA NTRS1975

Hematology and immunology studies

The hematology and immunology program conducted in support of the Apollo missions was designed to acquire specific laboratory data relative to the assessment of the health status of the astronauts prior to their commitment to space flight. A second objective was to detect and identify any alterations in the normal functions of the immunohematologic systems which could be attributed to space flight exposure, and to evaluate the significance of these changes relative to man's continuing participation in space flight missions. Specific changes observed during the Gemini Program formed the basis for the major portion of the hematology-immunology test schedule. Additional measurements were included when their contribution to the overall interpretation of the flight data base became apparent.

Stephen L. Kimzey↗
NASA NTRS2003

Hypergravity-Induced Changes in Hematological and Lymphocyte Function Parameters in a Mouse Model

The purpose of this study was to quantify hypergravity-induced changes in hematological and lymphocyte characteristics. Mice were subjected to 1, 2, and 3G and euthanized on days 1 , 4, 7, 10, and 21. The data show that increased gravitational force resulted in persistent hypothermia. Red blood cell (RBC) counts, hematocrit, and hemoglobin were reduced by day 21, whereas hemoglobin and RBC volume were low at most times of measurement. A transient increase was noted in platelet numbers in the 3G group. Fluctuations in spontaneous blastogenesis of lymphocytes were dependent upon centrifugation time and not gravity. Changes in splenocyte responses to T and B cell mitogens due to gravity were also noted. Cytokine production was primarily affected during the first week; IL-2, IL-4 and TNF-alpha were increased, whereas IFN-gamma was decreased. These findings indicate that altered gravity can influence both hematological and functional variables that may translate into serious health consequences.

Gridley, Daila S.↗
NASA NTRS1972

Hematologic responses to hypobaric hyperoxia.

Study of the effects of hypoxia, activity, and G forces on human hematopoiesis in an attempt to elucidate these phenomena more precisely. Eight subjects were exposed to an atmosphere of 100% O2 at 258 mm Hg for 30 days, and thereafter immediately exposed to transverse G forces, simulating the Gemini flights' reentry profile. All subjects displayed a significant continuous decline in red cell mass during the exposure period, as measured by the carbon monoxide-dilution method. The Cr51 method also indicated a decline in red blood corpuscle mass. The decrease in red cell mass was due to suppression of erythropoiesis and to hemolysis. After exposure to hyperoxia, all subjects exhibited elevated plasma hemoglobin levels, decreased reticulocyte counts, and decreased red cell survivals. CO production rates and urine erythropoietin levels were unchanged. Two hours after termination of exposure to hyperoxia, all subjects exhibited increased reticulocyte counts which were sustained for longer than two weeks. The progressive decrease in red cell mass was promptly arrested on return to ground level atmospheres. Within 116 days after exposure to hyperoxia, the hematologic parameters of all eight subjects had returned to control levels.

Larkin, E. C.↗
NASA NTRS1973

Special hematologic effects (M115), part E

All routine hematological measurements for the Skylab simulation test were within normal astronaut population limits for the CDR, SPT, and PLT, with one exception: A significant lymphopenia was observed in the PLT during the post test period, possibly the reflection of increased adrenal corticoid secretion. No ultrastructural red cell membrane abnormalities were observed in any of the subjects, nor were any red corpuscle morphological abnormalities noted. Slight elevations in the PLT's red corpuscular potassium were observed in the younger corpuscles after chamber entrance and again upon egress. This probably represents newly released young red cells from hematopoietic tissue. Flame photometric analyses confirm the fact that potassium is indeed higher in the younger cells of all subjects examined.

Kimzey, S. L.↗
NASA NTRS1974

Experiment M115: Special hematologic effects: Dynamic changes in red cell shape in response to the space-flight environment

The significance of the transformations in red cell shape observed during the Skylab study must be considered relative to the limitation of man's participation in extended space flight missions. The results of this one study are not conclusive with respect to this question. Based on these examinations of red cells in normal, healthy men and based on other Skylab experiment data relative to the functional capacity of the red cells in vitro and the performance capacity of man as an integrated system, the changes observed would not appear to be the limiting factor in determining man's stay in space. However, the results of this experiment and the documented red cell mass loss during space flight raise serious questions at this time relative to the selection criteria utilized for passengers and crews of future space flights. Until the specific cause and impact of the red cell shape change on cell survival in vivo can be resolved, individuals with diagnosed hematologic abnormalities should not be considered as prime candidates for missions, especially those of longer duration.

Kimzey, S. L.↗
NASA NTRS1975

Skylab experiment results: Hematology studies

Studies were conducted to evaluate specific aspects of man's immunologic and hematologic systems that might be altered by or respond to the space flight environment. Biochemical functions investigated included cytogenetic damage to blood cells, immune resistance to disease, regulation of plasma and red cell volumes, metabolic processes of the red blood cell, and physicochemical aspects of red blood cell function. Measurements of hematocrit value showed significant fluctuations postflight, reflecting observed changes in red cell mass and plasma volume. The capacity of lymphocytes to respond to an in vitro mitogenic challenge was repressed postflight, and appeared to be related to mission duration. Most other deviations from earth function in these systems were minor or transient.

Kimzey, S. L.↗
NASA NTRS1975

Hematologic changes in mice during and after exposure to severe hypobaric hypoxia

Exposing mice to an atmospheric pressure of 300 mm Hg for 16 d caused a variety of hematologic effects. Hematocrit increased rapidly in the first 8 d of exposure and slowly in the second 8 d. Reticulocyte counts rose above normal, peaked on day 8, and then fell rapidly toward the control level. Macrocytic erythrocytes, formed during exposure, remained macrocytic after the termination of exposure and after the loss of their reticulum. The posthypoxic mice proved sensitive for erythropoietin bioassay. Mice injected with normal dog serum showed a significantly higher incorporation of Fe-59 than control mice injected with physiologic saline. A reduction of the duration of exposure to 10 d resulted in only a slight decrease in the sensitivity of the mouse bioassay system. However, a 16-d exposure at a pressure of 360 mm Hg resulted in considerably less sensitive bioassay animals.

Huff, J. E.↗
NASA NTRS1976

Hematology and immunology studies - The second manned Skylab mission

The hematologic and immunologic functions of the Skylab 3 astronauts were monitored during the preflight, inflight, and postflight phases of the mission. Plasma protein profiles showed high consistency in all phases. A transient suppression of lymphocyte responsiveness was observed postflight. A reduction in the circulating blood volume due to drops in both the plasma volume and red cell mass was found. The loss of red cell mass is most likely a suppressed erythrypoiesis. The functional integrity of the circulating red cells did not appear to be compromised in the course of flight.

Kimzey, S. L.↗
NASA NTRS1985

Hematologic parameters of astrorats flown on SL-3

Hematologic studies were performed on a group of large and small rats which were sacrificed after flying in life sciences shuttle engineering flight SL-3. The results are presented on flight (F) and control (C) 200 gm rats. The small flight animals demonstrated a significant increase in hematocrits, red blood cell counts, hemoglobins and peripheral blood percentages of neutrophils as well as a decrease in percentage of lymphocytes. Erythropoietin (Ep) determinations were similar for the two groups as were the bone marrow an spleen differential counts. In vitro cultures for erythroid colonies of bone marrow showed that in response to different doses of Ep, in all cases where differnces were statistically significant, the F rats had increased colony counts. The changes in red cell parameters could be caused by a decrease in plasma volume. However, no isotopic studies were possible on this flight and this lack points up the need for such studies to determine the red cell mass and plasma volume.

Lange, R. D.↗
NASA NTRS1992

Biochemical, endocrine, and hematological factors in human oxygen tolerance extension: Predictive studies 6

The Predictive Studies VI (Biochemical, endocrine, and hematological factors in human oxygen tolerance extension) Program consisted of two related areas of research activity, integrated in design and performance, that were each based on an ongoing analysis of human organ oxygen tolerance data obtained for the continuous oxygen exposures of the prior Predictive Studies V Program. The two research areas effectively blended broad investigation of systematically varied intermittent exposure patterns in animals with very selective evaluation of specific exposure patterns in man.

Lambertsen, C. J.↗