Effects of space flights on human allergic status (IgE-mediated sensitivity)

Suppression of the immune system after space flights of different duration has been reported earlier by Konstantinova [Immune system in extreme conditions, Space immunology. B. 59. M. Science 1988. 289p. (in Russian) [4]; Immunoresistance of man in space flight, Acta Astronautica 23 (1991) 123–127 [5]]. Changes in T- and B-mediated activities of the immune system were demonstrated during and after space flight. However, the influence of the space flight conditions on the allergic status of cosmonauts and astronauts is still unclear. The goal of this investigation was to analyze total blood IgE levels, specific IgE-antibodies and interleukin-4 in blood of Russian crew members before and after space flights to the International Space Station (ISS) and during a long-term isolation study. For this purpose, we used the ELISA assays as well as other special kits. It was noticed that four out of nine cosmonauts had high total serum IgE (more than normal clinical values of 120 IU/ml). At the same time, there were no statistically significant changes in serum IgE levels before and after long-term space flights (128–195 days). A similar situation was observed regarding preflight IgE levels of cosmonauts who performed short-term flights (7–11 days). However, seven out of 11 cosmonauts had increased IgE level in blood post short flights as compared with pre-flight values. We also measured specific IgE-antibodies, because their high concentration may cause the increased production of total IgE indicating sensitization of cosmonauts. This becomes more important when humans spend a longer time in the closed environment of a space vehicle. Also our ground-based investigations showed that a stay in such conditions does not enhance sensitization to allergens (total number of tested allergens 27) including food, inhalants and cross-reactive proteins. Serum interleukin-4 level measured after short- and long-term space flights was identical. A linear correlation between levels of immunoglobulin E and interleukin-4 also was not significant. Despite the fact that our investigations did not establish any influence of space flight on sensitization and development of immediate-type allergic reactions, they demonstrated the necessity to control the allergic status of cosmonauts very carefully both before and after space flights. At the same time, it is necessary to pay special attention to outcomes of atopic individuals with high pre-flight level of total blood IgE.     

Plasma and urine catecholamine levels in cosmonauts during long-term stay on Space Station Salyut-7.

The activity of the sympathetic adrenal system in cosmonauts exposed to a stay in space lasting for about half a year has so far been studied only by measuring catecholamine levels in plasma and urine samples taken before space flight and after landing. The device "Plasma 01", specially designed for collecting and processing venous blood from subjects during space flight on board the station Salyut-7 rendered it possible for the first time to collect and freeze samples of blood from cosmonauts in the course of a long-term 237-day space flight. A physician-cosmonaut collected samples of blood and urine from two cosmonauts over the period of days 217-219 of their stay in space. The samples were transported to Earth frozen. As indicators of the sympathetic adrenal system activity, plasma and urine concentrations of epinephrine and norepinephrine as well as urine levels of the catecholamine metabolites metanephrine, normetanephrine, and vanillylmandelic acid were determined before, during and after space flight. On days 217-219 of space flight plasma epinephrine and norepinephrine levels were slightly increased, yet not substantially different from normal. During stress situations plasma norepinephrine and epinephrine levels usually exhibit a manifold increase. On days 217-219 of space flight norepinephrine and epinephrine levels in urine were comparable with pre-flight values and the levels of their metabolites were even significantly decreased. All the parameters studied, particularly plasma norepinephrine as well as urine norepinephrine, normetanephrine, and vanillylmandelic acid, reached the highest values 8 days after landing. The results obtained suggest that, in the period of days 217-219 of the cosmonauts stay in space in the state of weightlessness, the sympathetic adrenal system is either not activated at all or there is but a slight activation induced by specific activities of the cosmonauts, whereas in the process of re-adaptation after space flight on Earth this system is considerably more markedly activated.     

Lichens survive in space: results from the 2005 LICHENS experiment

This experiment was aimed at establishing, for the first time, the survival capability of lichens exposed to space conditions. In particular, the damaging effect of various wavelengths of extraterrestrial solar UV radiation was studied. The lichens used were the bipolar species Rhizocarpon geographicum and Xanthoria elegans, which were collected above 2000 m in the mountains of central Spain and as endolithic communities inhabiting granites in the Antarctic Dry Valleys. Lichens were exposed to space in the BIOPAN-5 facility of the European Space Agency; BIOPAN-5 is located on the outer shell of the Earth-orbiting FOTON-M2 Russian satellite. The lichen samples were launched from Baikonur by a Soyuz rocket on May 31, 2005, and were returned to Earth after 16 days in space, at which time they were tested for survival. Chlorophyll fluorescence was used for the measurement of photosynthetic parameters. Scanning electron microscopy in back-scattered mode, low temperature scanning electron microscopy, and transmission electron microscopy were used to study the organization and composition of both symbionts. Confocal laser scanning microscopy, in combination with the use of specific fluorescent probes, allowed for the assessment of the physiological state of the cells. All exposed lichens, regardless of the optical filters used, showed nearly the same photosynthetic activity after the flight as measured before the flight. Likewise, the multimicroscopy approach revealed no detectable ultrastructural changes in most of the algal and fungal cells of the lichen thalli, though a greater proportion of cells in the flight samples had compromised membranes, as revealed by the LIVE/DEAD BacLight Bacterial Viability Kit. These findings indicate that most lichenized fungal and algal cells can survive in space after full exposure to massive UV and cosmic radiation, conditions proven to be lethal to bacteria and other microorganisms. The lichen upper cortex seems to provide adequate protection against solar radiation. Moreover, after extreme dehydration induced by high vacuum, the lichens proved to be able to recover, in full, their metabolic activity within 24 hours.     

Psychophysiological reactivity under Mir-simulation and real micro-G

A complex psychophysiological test battery (ECG, blood pressure, SCL, finger temperature e.t.c.) was applied on two subjects in space. It could be shown that the subjects react under space conditions differently than on earth. The data received could be classified into four types of regulation. The subjects changed this type of regulation during the flight and returned to their former pattern after the flight.     

Autonomic regulation of circulation and cardiac contractility during a 14-month space flight

The space flight of physician cosmonaut V.V. Polyakov, the longest to date (438 days), has yielded new data about human adaptation to long-term weightlessness. Autonomic regulation of circulation and cardiac contractility were evaluated in three experiments entitled Pulstrans, Night, and Holter. In the Pulstrans experiment electrocardiographic (ECG), ballistocardiographic (BCG), seismocardiographic (SCG), and some other parameters were recorded. In the Night experiment, only the ballistocardiogram was recorded, but a special feature of this experiment is that the BCG records were obtained with a contactless method. This method has several advantages, the most important of which are the possibility of studying slow-wave variations in physiologic parameters (ultradian rhythms) on the basis of recordings made under standard conditions over a prolonged period. The Holter experiment (24-hour electrocardiographic monitoring) used a portable cardiorecorder (Spacelab, USA). The obtained electrocardiographic data were used to analyze heart rate variability. In the first 6 months of the 14-month flight, the dynamics of cardiovascular parameters in V.V. Polyakov was virtually the same as in the other cosmonauts. The data obtained after the first 6 months of Polyakov's sojourn in space are unique and mention should be made of at least three important aspects: (1) activation of a new, additional adaptive mechanism in the 8th-9th months of flight, as is evidenced by alterations in the periodicity and power of superslow wave oscillations (ultradian rhythms) reflecting the activity of the subcortical cardiovascular centers and of the higher levels of autonomic regulation; (2) growth of cardiac contractility accompanied by a decrease in heart rate during the last few months of flight; (3) a considerable increase in the daily average values of absolute power of heart rate's variability MF component, which reflects the activity of the vasomotor center. Specific mechanisms of adaptation to weightless conditions appear to be associated with activation of higher autonomic centers. The hypothesis that central levels of circulation regulation are activated in a long-term space flight was investigated by analyzing of ultradian rhythms in nighttime. The data, received during the flight of V. V. Polyakov, show, that the process of human adaptation to long influence of weightlessness consists of a number of consecutive stages, during which the activation of more and more high levels of control system of physiological functions occurs.     

The dynamics of blood biochemical parameters in cosmonauts during long-term space flights

Most of the previously obtained data on cosmonauts' metabolic state concerned certain stages of the postflight period. In this connection, all conclusions, as to metabolism peculiarities during the space flight, were to a large extent probabilistic. The purpose of this work was study of metabolism characteristics in cosmonauts directly during long-term space flights. In the capillary blood samples taken from a finger, by "Reflotron IV" biochemical analyzer, "Boehringer Mannheim" GmbH, Germany, adapted to weightlessness environments, the activity of GOT, GPT, CK, gamma-GT, total and pancreatic amylase, as well as concentration of hemoglobin, glucose, total bilirubin, uric acid, urea, creatinine, total, HDL- and LDL cholesterol, triglycerides had been determined. HDL/LDL-cholesterol ratio also was computed. The crewmembers of 6 main missions to the "Mir" orbital station, a total of 17 cosmonauts, were examined. Biochemical tests were carried out 30-60 days before launch, and in the flights different stages between the 25-th and the 423-rd days of flights. In cosmonauts during space flight had been found tendency to increase, in compare with basal level, GOT, GPT, total amylase activity, glucose and total cholesterol concentration, and tendency to decrease of CK activity, hemoglobin, HDL-cholesterol concentration, and HDL/LDL - cholesterol ratio. Some definite trends in variations of other determined biochemical parameters had not been found. The same trends of mentioned biochemical parameters alterations observed in majority of tested cosmonauts, allows to suppose existence of connection between noted metabolic alterations with influence of space flight conditions upon cosmonaut's body. Variations of other studied blood biochemical parameters depends on, probably, pure individual causes.     

Autonomic function testing aboard the ISS using “PNEUMOCARD”

Investigations of blood pressure, heart rate (HR), and heart rate variability (HRV) during long term space flights on board the “ISS” have shown characteristic changes of autonomic cardiovascular control. Therefore, alterations of the autonomic nervous system occurring during spaceflight may be responsible for in- and post-flight disturbances. The device “Pneumocard” was developed to further investigate autonomic cardiovascular and respiratory function aboard the ISS. The hard-software diagnostic complex “Pneumocard” was used during in-flight experiment aboard ISS for autonomic function testing. ECG, photoplethysmography, respiration, transthoracic bioimpedance and seismocardiography were assessed in one male cosmonaut (flight lengths six month). Recordings were made prior to the flight, late during flight, and post-flight during spontaneous respiration and controlled respiration at different rates.HR remained stable during flight. The values were comparable to supine measurements on earth. Respiratory frequency and blood pressure decreased during flight. Post flight HR and BP values increased compared to in-flight data exceeding pre-flight values. Cardiac time intervals did not change dramatically during flight. Pulse wave transit time decreased during flight. The maximum of the first time derivative of the impedance cardiogram, which is highly correlated with stroke volume was not reduced in-flight.Our results demonstrate that autonomic function testing aboard the ISS using “Pneumocard” is feasible and generates data of good quality. Despite the decrease in BP, pulse wave transit time was found reduced in space as shown earlier. However, cardiac output did not decrease profoundly in the investigated cosmonaut.Autonomic testing during space flight detects individual changes in cardiovascular control and may add important information to standard medical control. The recent plans to support a flight to Mars, makes these kinds of observations all the more relevant and compelling.     

Effect of geomagnetic field disturbances on the adaptive stress reaction of cosmonauts

Investigations of the effect of geomagnetic activity factors on the cardiac rhythm regulation and arterial pressure of cosmonauts during the expeditions onboard the Soyuz spacecraft, and the MIR and ISS orbital space stations was carried out for various durations of flight in weightlessness and, under control. Groups of cosmonauts were inspected under flight conditions outside the geomagnetic disturbances and in ground preflight conditions, during disturbances without them. The presence of specific effect of geomagnetic disturbances on the system of vegetative regulation of blood circulation of cosmonauts during the flight was demonstrated for the first time. The response of cosmonauts’ cardiac rhythm on the magnetic storm is definitely revealed; however, it depends on the initial functional background and, in particular, on the state of mechanisms of vegetative regulation (the duration of flight and adaptation to it).     

Predictors of immune function in space flight

Of all of the environmental conditions of space flight that might have an adverse effect upon human immunity and the incidence of infection, space radiation stands out as the single-most important threat. As important as this would be on humans engaged in long and deep space flight, it obviously is not possible to plan Earth-bound radiation and infection studies in humans. Therefore, we propose to develop a murine model that could predict the adverse effects of space flight radiation and reactivation of latent virus infection for humans. Recent observations on the effects of gamma and latent virus infection demonstrate latent virus reactivation and loss of T cell mediated immune responses in a murine model. We conclude that using this small animal method of quantitating the amounts of radiation and latent virus infection and resulting alterations in immune responses, it may be possible to predict the degree of immunosuppression in interplanetary space travel for humans. Moreover, this model could be extended to include other space flight conditions, such as microgravity, sleep deprivation, and isolation, to obtain a more complete assessment of space flight risks for humans.     

空间站空空支架天线热设计与仿真分析

为研究核心舱飞行姿态、空间外热流、核心舱发动机羽流参数以及天线外表面热控涂层对空间站空空支架天线温度的综合影响,验证天线被动热控设计的有效性,进行了2种低温工况和6种高温工况的热分析。结果显示:低温工况下,通信天线惯性飞行时的最低温度低于正向飞行时的;展开臂多层表面最低温度为-85 ℃,满足温控指标。高温工况下,通信天线惯性飞行时的温度高于正向飞行时的;轨控发动机的羽流热效应大于偏航发动机的。通信天线内外表面均喷涂ACR-1温控白漆,1倍轨控发动机羽流热流密度时,最高温度为123 ℃,可满足实际使用要求。     

气动辅助空间交会最优轨道设计与闭环导引律

给出了同平面HEO-LEO实现空间交会的必要条件;研究了基于气动辅助轨道转移技术实现同平面HEO-LEO的空间交会方案,通过设计一条标准的同平面HEO-LEO气动辅助轨道转移的最优轨迹,得到了轨道转移飞行器(OTV)与目标实现交会必须满足的标准相角;最后对大气飞行段设计了非线性最优闭环导引律,通过引入Lyapunov最陡下降函数,对函数中相应参数进行适当调整,使应用闭环导引律得到的大气内飞行轨迹与最优轨迹充分接近,仿真结果表明该气动辅助空间交会方法正确、可行。     

Mutagenesis in bacterial spores exposed to space and simulated martian conditions: data from the EXPOSE-E spaceflight experiment PROTECT

As part of the PROTECT experiment of the EXPOSE-E mission on board the International Space Station (ISS), the mutagenic efficiency of space was studied in spores of Bacillus subtilis 168. After 1.5 years' exposure to selected parameters of outer space or simulated martian conditions, the rates of induced mutations to rifampicin resistance (Rif(R)) and sporulation deficiency (Spo(-)) were quantified. In all flight samples, both mutations, Rif(R) and Spo(-), were induced and their rates increased by several orders of magnitude. Extraterrestrial solar UV radiation (>110?nm) as well as simulated martian UV radiation (>200?nm) led to the most pronounced increase (up to nearly 4 orders of magnitude); however, mutations were also induced in flight samples shielded from insolation, which were exposed to the same conditions except solar irradiation. Nucleotide sequencing located the Rif(R) mutations in the rpoB gene encoding the β-subunit of RNA polymerase. Mutations isolated from flight and parallel mission ground reference (MGR) samples were exclusively localized to Cluster I. The 21 Rif(R) mutations isolated from the flight experiment showed all a C to T transition and were all localized to one hotspot: H482Y. In mutants isolated from the MGR, the spectrum was wider with predicted amino acid changes at residues Q469K/L/R, H482D/P/R/Y, and S487L. The data show the unique mutagenic power of space and martian surface conditions as a consequence of DNA injuries induced by solar UV radiation and space vacuum or the low pressure of Mars.     

Male and female characteristics in vestibular testing: a step toward the selection of the best participants for space flight

Vestibular disturbances in connection with space flight were reported by a majority of participating astronauts and cosmonauts. These include motion sickness symptoms in the first few days of the space flight, as well as standing, gait and orientation disturbances after the return to Earth. The Aerospace Medical Community has been trying to select those people that are particularly adapted to the above stresses or that can be further adapted through training programs. As the circle of selectees extends to women, the problem arises as to whether differences between men and women exist under the conditions of space flight. In seeking answers to this question we studied a group of 42 women and 44 men, who were further subdivided according to their subjective motion sickness sensitivity, as determined by a questionnaire. Using this material, 26 men and 22 women were designated as motion sickness resistant, and 18 men and 20 women were designated as nonresistant. The vestibular test battery given these test subjects consisted of caloric, rotatory, optokinetic, vestibulo-spinal and vestibulo-vegetative testing. Because of the mixed orthostatic and vestibular problems seen after space flights, we also studied the response of the vestibular apparatus during peripheral blood pooling as induced by lower body negative pressure. The collected historical and test data are analyzed in this paper with emphasis on the relationship to motion sickness tendency.     

Anesthesia, surgical aid and resuscitation in manned space missions.

When discussing problems related to medical service in space flight, particular attention should be given to the specific living conditions and changes associated with space flight. In disease and injury, surgery can be provided only after conservative therapy has failed. In this context gnotobiological chambers allowing surgery in aseptic conditions seem promising. A portable set of interchangeable surgical tools should be made of light-weight alloys that can be readily sterilized. Electroanalgesia in combination with auriculoacupuncture as well as peridureal anesthesia may be used as they allow normal operations in autonomous space flight conditions. Changes in the sympatho-adrenal and kallikrein-kinin systems, as well as water-electrolyte balance, should be taken into account in developing methods and means of medical service in critical situations. Special attention should be given to the prevention and treatment of brain edema in view of weightlessness-induced cephalad fluid shifts.     

火星稀薄大气参数对进入器气动特性的影响

针对火星稀薄大气环境的不确定性对进入器气动特性的影响问题,先以海盗号火星进入器的飞行试验数据对发展的三维并行直接模拟蒙特卡罗(DSMC)仿真软件进行了算例校验,再以火星科学实验室外形为例,计算气体组分、密度、温度及速度等来流参数的不确定性对进入器气动特性的影响偏差,定性定量给出火星高空稀薄环境下大气不确定性所带来的气动力特性规律。研究结果表明,通过与海盗号飞行实验数据的对比校验了所建立方法的正确性与可靠性;CO2大气环境对进入器气动特性的影响较大,利用空气稀薄环境中的计算及实验结果亦需进行CO2效应修正,这一点与连续流区的结论一致;来流密度及速度的不确定性对气动力、力矩特性均有影响,而来流温度影响的最大偏差小于0.5%;纵向压心对来流密度、温度及速度的扰动均不敏感。     

飞行参数对导弹发动机羽流的影响

对导弹发动机在不同飞行条件下的羽流进行数值模拟,得到飞行参数对导弹发动机羽流的影响规律,为载机挂点设计和制定发射边界提供了相应的理论依据。计算结果表明,在相同飞行马赫数下随飞行高度的增加,导弹羽流边界随之增加：在相同飞行高度下随飞行马赫数的增加,导弹羽流边界随之减小,同时导弹羽流结构也随飞行奈件变化而有很大的不同。数值模拟与地面试验结果一致,计算具有较高的可信度。     

Adaptation of neuromuscular activation patterns during treadmill walking after long-duration space flight

The precise neuromuscular control needed for optimal locomotion, particularly around heel strike and toe off, is known to he compromised after short duration (8- to 15-day) space flight. We hypothesized here that longer exposure to weightlessness would result in maladaptive neuromuscular activation during postflight treadmill walking. We also hypothesized that space flight would affect the ability of the sensory-motor control system to generate adaptive neuromuscular activation patterns in response to changes in visual target distance during postflight treadmill walking. Seven crewmembers, who completed 3- to 6-month missions, walked on a motorized treadmill while visually fixating on a target placed 30 cm (NEAR) or 2 m (FAR) from the subject's eyes. Electronic foot switch data and surface electromyography were collected from selected muscles of the right lower limb. Results indicate that the phasic features of neuromuscular activation were moderately affected and the relative amplitude of activity in the tibialis anterior and rectus femoris around toe off changed after space flight. Changes also were evident after space flight in how these muscles adapted to the shift in visual target distance.     

Methodological approach to study of cosmonauts errors and its instrumental support

The methodological approach to the study of cosmonauts errors is discussed in the paper. Within its framework an error is considered in psychophysiological aspect as consequence of cosmonaut "psychophysiological troubles" caused by combined effect of flight extreme conditions on his/her organism. This approach was used for the investigation of interrelation between cosmonauts errors, their psychophysiological state and work-rest schedule peculiarities. It includes procedures of expert analysis of data received in the course of radio and TV sessions with crew, analysis of timelines as well deviations in "crew-spacecraft" system functioning. These data are accumulated, systematized and processed in data base. Realization of the suggested approach does not require specialized onboard equipment and crew members time expenditure. Some results of inflight data analysis are presented to illustrate its potentials.     

Study of values and interpersonal perception in cosmonauts on board of international space station

The increased heterogeneity of International Space Station (ISS) crews′ composition (in terms of nationality, profession and gender) together with stressful situations, due to space flight, can have a significant impact on group interaction and cohesion, as well as on communications with Mission Control Center (MCC) and the success of the mission as a whole. Culturally related differences in values, goals, and behavioral norms could influence mutual perception and, thus, cohesive group formation. The purpose of onboard “Interaction-Attitudes” experiment is to study the patterns of small group (space crew) behavior in extended space flight. Onboard studies were performed in the course of ISS Missions 19–30 with participation of twelve Russian crewmembers. Experimental schedule included 3 phases: preflight training and Baseline Data Collection; inflight activities once in two weeks; post-flight measurement. We used Personal Self-Perception and Attitudes (PSPA) software for analyzing subjects′ attitudes toward social environment (crewmembers and MCC). It is based on the semantic differential and the repertory grid technique. To study the content of interpersonal perception we used content-analysis with participation of the experts, independently attributing each construct to the 17 semantic categories, which were described in our previous study. The data obtained demonstrated that the system of values and personal attitudes in the majority of participated cosmonauts remained mostly stable under stress-factors of extended space flight. Content-analysis of the important criteria elaborated by the subjects for evaluation of their social environment, showed that the most valuable personal traits for cosmonauts were those that provided the successful fulfillment of professional activity (motivation, intellectual level, knowledge, and self-discipline) and good social relationships (sociability, friendship, and tolerance), as well. Post-flight study of changes in perceptions, related to Real Self-image, did not reveal significant differences between the images of Russian crew-members and representatives from foreign space agencies. A certain difference in perceptions was found in cosmonauts with more integrated system of evaluations: after space flight they perceived foreign participants as “closer” to their Ideal, while Russian crew-members were perceived mostly as “distant” from Ideal Self of these subjects. Perceptions of people from Earth were also more critical. These differences are likely to be manifestations of interpersonal perception stereotypes. Described patterns of changes in perceptions of cosmonauts, who have performed space flight as a part of ISS multinational crew, allow us to suggest the recommendations for development of ISS crew training, in particular, it seems useful to increase the time of joint training for deepening of intercultural interaction.     

Psychological adaptation and salutogenesis in space: Lessons from a series of studies

Individuals who adapt positively to an inhospitable or extreme environment can derive benefit from their experiences. This positive effect may include an initial improvement in mental health as someone adjusts to the environment (adaptation) as well as more sustained personal growth during the mission (salutogenesis). We review relevant findings from our prior work, including two post-mission surveys of astronauts and cosmonauts, and three studies of crewmembers during missions in a space station simulator, the Mir space station, and the International Space Station (ISS). We also present new analyses showing evidence for adaptation to ISS missions. This finding replicates our previous results from the simulation study, but this effect was not found on the Mir. A better understanding of psychological adaptation and salutogenesis during space flight should help us develop strategies to enhance crewmembers’ in-flight stress tolerance and post-flight adjustment.