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Sara R Zwart - One of the best experts on this subject based on the ideXlab platform.
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men and women in Space bone loss and kidney stone risk after long duration Space Flight
The FASEB Journal, 2014Co-Authors: Scott A Smith, Linda C. Shackelford, Martina Heer, Sara R Zwart, Edgar K Hudson, Jennifer R MorganAbstract:Bone loss on Earth is more prevalent in women than men, leading to the assumption that women may be at greater risk from bone loss during Flight. Until recently, the number of women having flown long-duration missions was too small to allow any type of statistical analysis. We report here data from 42 astronauts on long-duration missions to the International Space Station, 33 men and 9 women. Bone mineral density (dual-energy X-ray absorptiometry), bone biochemistry (from blood and urine samples), and renal stone risk factors were evaluated before and after Flight. Data were analyzed in two groups, based on available resistance exercise equipment. The response of bone mineral density to Flight was the same for men and women, and the typical decrease in bone mineral density (whole body and/or regional) after Flight was not observed for either sex for those using an Advanced Resistive Exercise Device. Bone biochemistry, specifically markers of formation and resorption, generally responded similarly in male and female astronauts. The response of urinary supersaturation risk to Space Flight was not significantly different between men and women, although risks were typically increased after Flight in both groups and risks were generally greater in men than in women before and after Flight. Overall, the bone and renal stone responses of men and women to Space Flight were not different.
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iron status and its relations with oxidative damage and bone loss during long duration Space Flight on the international Space station
The American Journal of Clinical Nutrition, 2013Co-Authors: Sara R Zwart, Jennifer L L Morgan, Scott M SmithAbstract:Background: Increases in stored iron and dietary intake of iron during Space Flight have raised concern about the risk of excess iron and oxidative damage, particularly in bone. Objectives: The objectives of this study were to perform a comprehensive assessment of iron status in men and women before, during, and after long-duration Space Flight and to quantify the association of iron status with oxidative damage and bone loss. Design: Fasting blood and 24-h urine samples were collected from 23 crew members before, during, and after missions lasting 50 to 247 d to the International Space Station. Results: Serum ferritin and body iron increased early in Flight, and transferrin and transferrin receptors decreased later, which indicated that early increases in body iron stores occurred through the mobilization of iron to storage tissues. Acute phase proteins indicated no evidence of an inflammatory response during Flight. Serum ferritin was positively correlated with the oxidative damage markers 8-hydroxy-2#-deoxyguanosine (r = 0.53, P , 0.001) and prostaglandin F2a (r = 0.26, P , 0.001), and the greater the area under the curve for ferritin during Flight, the greater the decrease in bone mineral density in the total hip (P = 0.031), trochanter (P = 0.006), hip neck (P = 0.044), and pelvis (P = 0.049) after Flight. Conclusion: Increased iron stores may be a risk factor for oxidative damage and bone resorption. Am J Clin Nutr doi: 10.3945/ajcn. 112.056465.
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Space Flight calcium implications for astronaut health Spacecraft operations and earth
Nutrients, 2012Co-Authors: Scott M Smith, Martina Heer, Torin Mccoy, Daniel B Gazda, Jennifer L L Morgan, Sara R ZwartAbstract:The Space Flight environment is known to induce bone loss and, subsequently, calcium loss. The longer the mission, generally the more bone and calcium are lost. This review provides a history of bone and calcium studies related to Space Flight and highlights issues related to calcium excretion that the Space program must consider so that urine can be recycled. It also discusses a novel technique using natural stable isotopes of calcium that will be helpful in the future to determine calcium and bone balance during Space Flight.
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long duration Space Flight and bed rest effects on testosterone and other steroids
The Journal of Clinical Endocrinology and Metabolism, 2012Co-Authors: Scott M Smith, Carolyn L Huntoon, Martina Heer, Zuwei Wang, Sara R ZwartAbstract:Context: Limited data suggest that testosterone is decreased during Space Flight, which could contribute to bone and muscle loss. Objective: The main objective was to assess testosterone and hormone status in long- and short-duration Space Flight and bed rest environments and to determine relationships with other physiological systems, including bone and muscle. Design: Blood and urine samples were collected before, during, and after long-duration Space Flight. Samples were also collected before and after 12- to 14-d missions and from participants in 30- to 90-d bed rest studies. Setting: Space Flight studies were conducted on the International Space Station and before and after Space Shuttle missions. Bed rest studies were conducted in a clinical research center setting. Data from Skylab missions are also presented. Participants: All of the participants were male, and they included 15 long-duration and nine short-duration mission crew members and 30 bed rest subjects. Main Outcome Measures: Serum total, ...
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the nutritional status of astronauts is altered after long term Space Flight aboard the international Space station
Journal of Nutrition, 2005Co-Authors: Scott M Smith, Sara R Zwart, Gladys Block, Barbara L Rice, Janis E DavisstreetAbstract:Defining optimal nutrient requirements is critical for ensuring crew health during long-duration Space exploration missions. Data pertaining to such nutrient requirements are extremely limited. The primary goal of this study was to better understand nutritional changes that occur during long-duration Space Flight. We examined body composition, bone metabolism, hematology, general blood chemistry, and blood levels of selected vitamins and minerals in 11 astronauts before and after long-duration (128-195 d) Space Flight aboard the International Space Station. Dietary intake and limited biochemical measures were assessed during Flight. Crew members consumed a mean of 80% of their recommended energy intake, and on landing day their body weight was less (P = 0.051) than before Flight. Hematocrit, serum iron, ferritin saturation, and transferrin were decreased and serum ferritin was increased after Flight (P < 0.05). The finding that other acute-phase proteins were unchanged after Flight suggests that the changes in iron metabolism are not likely to be solely a result of an inflammatory response. Urinary 8-hydroxy-2'-deoxyguanosine concentration was greater and RBC superoxide dismutase was less after Flight (P < 0.05), indicating increased oxidative damage. Despite vitamin D supplement use during Flight, serum 25-hydroxycholecalciferol was decreased after Flight (P < 0.01). Bone resorption was increased after Flight, as indicated by several markers. Bone formation, assessed by several markers, did not consistently rise 1 d after landing. These data provide evidence that bone loss, compromised vitamin D status, and oxidative damage are among critical nutritional concerns for long-duration Space travelers.
Scott M Smith - One of the best experts on this subject based on the ideXlab platform.
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iron status and its relations with oxidative damage and bone loss during long duration Space Flight on the international Space station
The American Journal of Clinical Nutrition, 2013Co-Authors: Sara R Zwart, Jennifer L L Morgan, Scott M SmithAbstract:Background: Increases in stored iron and dietary intake of iron during Space Flight have raised concern about the risk of excess iron and oxidative damage, particularly in bone. Objectives: The objectives of this study were to perform a comprehensive assessment of iron status in men and women before, during, and after long-duration Space Flight and to quantify the association of iron status with oxidative damage and bone loss. Design: Fasting blood and 24-h urine samples were collected from 23 crew members before, during, and after missions lasting 50 to 247 d to the International Space Station. Results: Serum ferritin and body iron increased early in Flight, and transferrin and transferrin receptors decreased later, which indicated that early increases in body iron stores occurred through the mobilization of iron to storage tissues. Acute phase proteins indicated no evidence of an inflammatory response during Flight. Serum ferritin was positively correlated with the oxidative damage markers 8-hydroxy-2#-deoxyguanosine (r = 0.53, P , 0.001) and prostaglandin F2a (r = 0.26, P , 0.001), and the greater the area under the curve for ferritin during Flight, the greater the decrease in bone mineral density in the total hip (P = 0.031), trochanter (P = 0.006), hip neck (P = 0.044), and pelvis (P = 0.049) after Flight. Conclusion: Increased iron stores may be a risk factor for oxidative damage and bone resorption. Am J Clin Nutr doi: 10.3945/ajcn. 112.056465.
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Space Flight calcium implications for astronaut health Spacecraft operations and earth
Nutrients, 2012Co-Authors: Scott M Smith, Martina Heer, Torin Mccoy, Daniel B Gazda, Jennifer L L Morgan, Sara R ZwartAbstract:The Space Flight environment is known to induce bone loss and, subsequently, calcium loss. The longer the mission, generally the more bone and calcium are lost. This review provides a history of bone and calcium studies related to Space Flight and highlights issues related to calcium excretion that the Space program must consider so that urine can be recycled. It also discusses a novel technique using natural stable isotopes of calcium that will be helpful in the future to determine calcium and bone balance during Space Flight.
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long duration Space Flight and bed rest effects on testosterone and other steroids
The Journal of Clinical Endocrinology and Metabolism, 2012Co-Authors: Scott M Smith, Carolyn L Huntoon, Martina Heer, Zuwei Wang, Sara R ZwartAbstract:Context: Limited data suggest that testosterone is decreased during Space Flight, which could contribute to bone and muscle loss. Objective: The main objective was to assess testosterone and hormone status in long- and short-duration Space Flight and bed rest environments and to determine relationships with other physiological systems, including bone and muscle. Design: Blood and urine samples were collected before, during, and after long-duration Space Flight. Samples were also collected before and after 12- to 14-d missions and from participants in 30- to 90-d bed rest studies. Setting: Space Flight studies were conducted on the International Space Station and before and after Space Shuttle missions. Bed rest studies were conducted in a clinical research center setting. Data from Skylab missions are also presented. Participants: All of the participants were male, and they included 15 long-duration and nine short-duration mission crew members and 30 bed rest subjects. Main Outcome Measures: Serum total, ...
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the nutritional status of astronauts is altered after long term Space Flight aboard the international Space station
Journal of Nutrition, 2005Co-Authors: Scott M Smith, Sara R Zwart, Gladys Block, Barbara L Rice, Janis E DavisstreetAbstract:Defining optimal nutrient requirements is critical for ensuring crew health during long-duration Space exploration missions. Data pertaining to such nutrient requirements are extremely limited. The primary goal of this study was to better understand nutritional changes that occur during long-duration Space Flight. We examined body composition, bone metabolism, hematology, general blood chemistry, and blood levels of selected vitamins and minerals in 11 astronauts before and after long-duration (128-195 d) Space Flight aboard the International Space Station. Dietary intake and limited biochemical measures were assessed during Flight. Crew members consumed a mean of 80% of their recommended energy intake, and on landing day their body weight was less (P = 0.051) than before Flight. Hematocrit, serum iron, ferritin saturation, and transferrin were decreased and serum ferritin was increased after Flight (P < 0.05). The finding that other acute-phase proteins were unchanged after Flight suggests that the changes in iron metabolism are not likely to be solely a result of an inflammatory response. Urinary 8-hydroxy-2'-deoxyguanosine concentration was greater and RBC superoxide dismutase was less after Flight (P < 0.05), indicating increased oxidative damage. Despite vitamin D supplement use during Flight, serum 25-hydroxycholecalciferol was decreased after Flight (P < 0.01). Bone resorption was increased after Flight, as indicated by several markers. Bone formation, assessed by several markers, did not consistently rise 1 d after landing. These data provide evidence that bone loss, compromised vitamin D status, and oxidative damage are among critical nutritional concerns for long-duration Space travelers.
Martina Heer - One of the best experts on this subject based on the ideXlab platform.
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men and women in Space bone loss and kidney stone risk after long duration Space Flight
The FASEB Journal, 2014Co-Authors: Scott A Smith, Linda C. Shackelford, Martina Heer, Sara R Zwart, Edgar K Hudson, Jennifer R MorganAbstract:Bone loss on Earth is more prevalent in women than men, leading to the assumption that women may be at greater risk from bone loss during Flight. Until recently, the number of women having flown long-duration missions was too small to allow any type of statistical analysis. We report here data from 42 astronauts on long-duration missions to the International Space Station, 33 men and 9 women. Bone mineral density (dual-energy X-ray absorptiometry), bone biochemistry (from blood and urine samples), and renal stone risk factors were evaluated before and after Flight. Data were analyzed in two groups, based on available resistance exercise equipment. The response of bone mineral density to Flight was the same for men and women, and the typical decrease in bone mineral density (whole body and/or regional) after Flight was not observed for either sex for those using an Advanced Resistive Exercise Device. Bone biochemistry, specifically markers of formation and resorption, generally responded similarly in male and female astronauts. The response of urinary supersaturation risk to Space Flight was not significantly different between men and women, although risks were typically increased after Flight in both groups and risks were generally greater in men than in women before and after Flight. Overall, the bone and renal stone responses of men and women to Space Flight were not different.
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Space Flight calcium implications for astronaut health Spacecraft operations and earth
Nutrients, 2012Co-Authors: Scott M Smith, Martina Heer, Torin Mccoy, Daniel B Gazda, Jennifer L L Morgan, Sara R ZwartAbstract:The Space Flight environment is known to induce bone loss and, subsequently, calcium loss. The longer the mission, generally the more bone and calcium are lost. This review provides a history of bone and calcium studies related to Space Flight and highlights issues related to calcium excretion that the Space program must consider so that urine can be recycled. It also discusses a novel technique using natural stable isotopes of calcium that will be helpful in the future to determine calcium and bone balance during Space Flight.
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long duration Space Flight and bed rest effects on testosterone and other steroids
The Journal of Clinical Endocrinology and Metabolism, 2012Co-Authors: Scott M Smith, Carolyn L Huntoon, Martina Heer, Zuwei Wang, Sara R ZwartAbstract:Context: Limited data suggest that testosterone is decreased during Space Flight, which could contribute to bone and muscle loss. Objective: The main objective was to assess testosterone and hormone status in long- and short-duration Space Flight and bed rest environments and to determine relationships with other physiological systems, including bone and muscle. Design: Blood and urine samples were collected before, during, and after long-duration Space Flight. Samples were also collected before and after 12- to 14-d missions and from participants in 30- to 90-d bed rest studies. Setting: Space Flight studies were conducted on the International Space Station and before and after Space Shuttle missions. Bed rest studies were conducted in a clinical research center setting. Data from Skylab missions are also presented. Participants: All of the participants were male, and they included 15 long-duration and nine short-duration mission crew members and 30 bed rest subjects. Main Outcome Measures: Serum total, ...
Leah R Bent - One of the best experts on this subject based on the ideXlab platform.
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selective weighting of cutaneous receptor feedback and associated balance impairments following short duration Space Flight
Neuroscience Letters, 2015Co-Authors: Nicholas D J Strzalkowski, Catherine R Lowrey, Stephen D. Perry, David R Williams, Scott J Wood, Leah R BentAbstract:The present study investigated the perception of low frequency (3 Hz) vibration on the foot sole and its relationship to standing balance following short duration Space Flight in nine astronauts. Both 3 Hz vibration perception threshold (VPT) and standing balance measures increased on landing day compared to pre-Flight. Contrary to our hypothesis, a positive linear relationship between these measures was not observed; however astronauts with the most sensitive skin (lowest 3 Hz VPT) were found to have the largest sway on landing day. While the change in foot sole sensitivity does not appear to directly relate to standing balance control, an exploratory strategy may be employed by astronauts whose threshold to pressure information is lower. Understanding sensory adaptations and balance control has implications to improve balance control strategies following Space Flight and in sensory impaired populations on earth.
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selective skin sensitivity changes and sensory reweighting following short duration Space Flight
Journal of Applied Physiology, 2014Co-Authors: Catherine R Lowrey, Nicholas D J Strzalkowski, Stephen D. Perry, David R Williams, Scott J Wood, Leah R BentAbstract:Skin sensory input from the foot soles is coupled with vestibular input to facilitate body orientation in a gravitational environment. Anecdotal observations suggest that foot sole skin becomes hypersensitive following Space Flight. The veritable level of skin sensitivity and its impact on postural disequilibrium observed post Space Flight have not been documented. Skin sensitivity of astronauts (n = 11) was measured as vibration perception at the great toe, fifth metatarsal and heel. Frequencies targeted four classes of receptors: 3 and 25 Hz for slow-adapting (SA) receptors and 60 and 250 Hz for fast-adapting (FA) receptors. Data were collected pre– and post–Space Flight. We hypothesized that skin sensitivity would increase post–Space Flight and correlate to balance measures. Decreased skin sensitivity was found on landing day at 3 and 25 Hz on the great toe. Hypersensitivity was found for a subset of astronauts (n = 6) with significantly increased sensitivity to 250 Hz at the heel. This subset displaye...
Six N. F. - One of the best experts on this subject based on the ideXlab platform.
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Marshall Space Flight Center Faculty Fellowship Program
2019Co-Authors: Six N. F., Karr G.Abstract:The 2018 Marshall Faculty Fellowship Program involved 16 faculty in the laboratories and departments at Marshall Space Flight Center. These faculty engineers and scientists worked with NASA collaborators on NASA projects, bringing new perspectives and solutions to bear. This Technical Memorandum is a compilation of the research reports of the 2018 Marshall Faculty Fellowship program, along with the Program Announcement (Appendix A) and the Program Description (Appendix B). The research affected the following five areas: (1) Materials (2) Propulsion (3) Spacecraft systems (4) Vehicle systems (5) Space science The materials investigations includes Lunar Regolith for habitats, friction stir welding, and composite joints. Propulsion studies included cryogenic tank pressurization, transmitted torque in a cryogenic environment, and condensation in presence of noncondensables, Europa Lander Deorbit Stage, and catalyst development for a hybrid rocket. Spacecraft systems include wireless sensor networks and printed electronic inks. Vehicle systems studies were performed on Mars ascent vehicle analysis, architecture models, and Space Launch System manual steering. Space science studies included planetary lava flow. Our goal is to continue the Marshall Faculty Fellowship Program funded by Center internal project offices. Faculty Fellows in this 2018 program represented the following minority-serving institutions: Alabama A&M University, Southern University, Delgado Community College, and Dillard University
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Marshall Space Flight Center Faculty Fellowship Program
2017Co-Authors: Damiani R., Six N. F.Abstract:The 2017 Marshall Faculty Fellowship Program involved 21 faculty in the laboratories and departments at Marshall Space Flight Center. These faculty engineers and scientists worked with NASA collaborators on NASA projects, bringing new perspectives and solutions to bear. This Technical Memorandum is a compilation of the research reports of the 2017 Marshall Faculty Fellowship program, along with the Program Announcement (Appendix A) and the Program Description (Appendix B). The research affected the following six areas: (1) Materials (2) Propulsion (3) Instrumentation (4) Spacecraft systems (5) Vehicle systems (6) Space science The materials investigations included composite structures, printing electronic circuits, degradation of materials by energetic particles, friction stir welding, Martian and Lunar regolith for in-situ construction, and polymers for additive manufacturing. Propulsion studies were completed on electric sails and low-power arcjets for use with green propellants. Instrumentation research involved heat pipes, neutrino detectors, and remote sensing. Spacecraft systems research was conducted on wireless technologies, layered pressure vessels, and two-phase flow. Vehicle systems studies were performed on life support-biofilm buildup and landing systems. In the Space science area, the excitation of electromagnetic ion-cyclotron waves observed by the Magnetospheric Multiscale Mission provided insight regarding the propagation of these waves. Our goal is to continue the Marshall Faculty Fellowship Program funded by Center internal project offices. Faculty Fellows in this 2017 program represented the following minority-serving institutions: Alabama A&M University and Oglala Lakota College
