Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.689
Filtrar
2.
Aerosp Med Hum Perform ; 92(2): 129-134, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33468296

RESUMO

INTRODUCTION: In the 1990s, Canada, member states of the European Space Agency, Japan, the Russian Federation, and the United States entered into an international agreement Concerning Cooperation on the Civil International Space Station. Among the many unique infrastructure challenges, partners were to develop a comprehensive international medical system and related processes to enable crew medical certification and medical support for all phases of missions, in a framework to support a multilateral space program of unprecedented size, scope, and degree of integration. During the Shuttle/Mir Program, physicians and specialized experts from the United States and Russia studied prototype systems and developed and operated collaborative mechanisms. The 1998 NASA Memoranda of Understanding with each of the other four partners established the Multilateral Medial Policy Board, the Multilateral Space Medicine Board, and the Multilateral Medical Operations Panel as medical authority bodies to ensure International Space Station (ISS) crew health and performance. Since 1998, the medical system of the ISS Program has ensured health and excellent performance of the international crewsan essential prerequisite for the construction and operation of the ISSand prevented mission-impacting medical events and adverse health outcomes. As the ISS is completing its second decade of crewed operation, it is prudent to appraise its established medical framework for its utility moving forward in new space exploration initiatives. Not only the ISS Program participants, but other nations and space agencies as well, concomitant with commercial endeavors in human spaceflight, can benefit from this evidence for future human exploration programs.Doarn CR, Polk JD, Grigoriev A, Comtois J-M, Shimada K, Weerts G, Dervay JP, Taddeo TA, Sargsyan A. A framework for multinational medical support for the International Space Station: a model for exploration. Aerosp Med Hum Perform. 2021; 92(2):129134.


Assuntos
Medicina Aeroespacial , Astronautas , Voo Espacial , Astronave , Canadá , Europa (Continente) , Humanos , Cooperação Internacional , Japão , Federação Russa , Estados Unidos
4.
Microbiome ; 9(1): 2, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397500

RESUMO

The inaugural "Microbiome for Mars" virtual workshop took place on July 13, 2020. This event assembled leaders in microbiome research and development to discuss their work and how it may relate to long-duration human space travel. The conference focused on surveying current microbiome research, future endeavors, and how this growing field could broadly impact human health and space exploration. This report summarizes each speaker's presentation in the order presented at the workshop.


Assuntos
Astronautas , Assistência à Saúde/tendências , Marte , Microbiota/fisiologia , Voo Espacial , Animais , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Humanos , Microbiota/genética
5.
Microbiome ; 9(1): 27, 2021 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-33487169

RESUMO

BACKGROUND: Human health is closely interconnected with its microbiome. Resilient microbiomes in, on, and around the human body will be key for safe and successful long-term space travel. However, longitudinal dynamics of microbiomes inside confined built environments are still poorly understood. Herein, we used the Hawaii Space Exploration Analog and Simulation IV (HI-SEAS IV) mission, a 1 year-long isolation study, to investigate microbial transfer between crew and habitat, in order to understand adverse developments which may occur in a future outpost on the Moon or Mars. RESULTS: Longitudinal 16S rRNA gene profiles, as well as quantitative observations, revealed significant differences in microbial diversity, abundance, and composition between samples of the built environment and its crew. The microbiome composition and diversity associated with abiotic surfaces was found to be rather stable, whereas the microbial skin profiles of individual crew members were highly dynamic, resulting in an increased microbiome diversity at the end of the isolation period. The skin microbiome dynamics were especially pronounced by a regular transfer of the indicator species Methanobrevibacter between crew members within the first 200 days. Quantitative information was used to track the propagation of antimicrobial resistance in the habitat. Together with functional and phenotypic predictions, quantitative and qualitative data supported the observation of a delayed longitudinal microbial homogenization between crew and habitat surfaces which was mainly caused by a malfunctioning sanitary facility. CONCLUSIONS: This study highlights main routes of microbial transfer, interaction of the crew, and origins of microbial dynamics in an isolated environment. We identify key targets of microbial monitoring, and emphasize the need for defined baselines of microbiome diversity and abundance on surfaces and crew skin. Targeted manipulation to counteract adverse developments of the microbiome could be a highly important strategy to ensure safety during future space endeavors. Video abstract.


Assuntos
Astronautas , Meio Ambiente Extraterreno , Microbiota , Pele/microbiologia , Voo Espacial , Astronave , Adulto , Ambiente Construído , Feminino , Hawaii , Humanos , Masculino , Microbiota/genética , RNA Ribossômico 16S/genética
6.
Curr Opin Ophthalmol ; 32(1): 69-73, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33196542

RESUMO

PURPOSE OF REVIEW: During prolonged spaceflight, astronauts often experience ocular changes, due to constant head-ward fluid shifts in space as compared with Earth. This article reviews symptoms, likely causes, and potential solutions, such as lower body negative pressure, to counteract space-associated neuroocular syndrome (SANS). RECENT FINDINGS: Low gravity conditions and other aspects of spaceflight affect the eye detrimentally, causing SANS which is characterized by optic disc edema, choroidal thickening, cotton wool spots, and a hyperopic shift. SANS is probably caused by altered hemodynamic flows in the head and neck as well as mildly elevated intracranial and intraocular pressures. Carbon dioxide and other chemicals in space-craft may influence SANS as well. SANS may be counteracted by using lower body negative pressure, thigh cuffs, spacecraft engineering, and/or artificial gravity by a centrifuge. SUMMARY: Prolonged space missions are associated with optic disc edema, choroidal thickening, cotton wool spots, and a hyperopic shift. Possible causes and countermeasures are currently being researched to reduce the risk of SANS. Although many countermeasures to SANS are under investigation lower body negative pressure exhibits great promise in counteracting the headward fluid shifts in space. Understanding and prevention of SANS is critical to future space exploration, especially to long-duration missions to the moon and Mars.


Assuntos
Doenças da Coroide/etiologia , Hiperopia/etiologia , Papiledema/etiologia , Voo Espacial , Transtornos da Visão/etiologia , Ausência de Peso/efeitos adversos , Astronautas , Doenças da Coroide/prevenção & controle , Deslocamentos de Líquidos Corporais , Humanos , Hiperopia/prevenção & controle , Pressão Intracraniana , Pressão Negativa da Região Corporal Inferior , Papiledema/prevenção & controle , Transtornos da Visão/prevenção & controle
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4160-4164, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018914

RESUMO

Wearable sensors provide the capability to noninvasively monitor physiological parameters during spaceflight, including those related to physical performance and daily activity. Regular monitoring of general health and exercise capabilities in astronauts can ensure adequate performance levels and record health changes caused by the space environment. Relevant measurables include vital signs, cardiovascular health, and activity monitoring. Wearable sensor devices can be comfortable for long-term use and easy to operate, which is particularly important during more autonomous future planetary missions. Many devices are currently being developed and tested, but few wearable devices or integrated "smart" garments have been assigned for regular use on the International Space Station. The unique needs of the space environment must be considered to facilitate the development and implementation of wearable devices, particularly "smart" sensor garments, for space applications.


Assuntos
Voo Espacial , Dispositivos Eletrônicos Vestíveis , Astronautas , Humanos , Monitorização Fisiológica , Desempenho Físico Funcional
8.
J Allergy Clin Immunol Pract ; 8(10): 3247-3250, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32971311

RESUMO

NASA implements required medical tests and clinical monitoring to ensure the health and safety of its astronauts. These measures include a pre-launch quarantine to mitigate the risk of infectious diseases. During space missions, most astronauts experience perturbations to their immune system that manifest as a detectable secondary immunodeficiency. On return to Earth, after the stress of re-entry and landing, astronauts would be most vulnerable to infectious disease. In April 2020, a crew returned from International Space Station to NASA Johnson Space Center in Houston, Texas, during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Post-flight quarantine protocols (both crew and contacts) were enhanced to protect this crew from SARS-CoV-2. In addition, specific additional clinical monitoring was performed to determine post-flight immunocompetence. Given that coronavirus disease 2019 (COVID-19) prognosis is more severe for the immunocompromised, a countermeasures protocol for spaceflight suggested by an international team of scientists could benefit terrestrial patients with secondary immunodeficiency.


Assuntos
Astronautas , Infecções por Coronavirus/prevenção & controle , Hospedeiro Imunocomprometido/imunologia , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Quarentena/métodos , Voo Espacial , Estresse Fisiológico/imunologia , Betacoronavirus , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Coronavirus/imunologia , Suplementos Nutricionais , Terapia por Exercício , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Imunoglobulina G/uso terapêutico , Interleucina-2/uso terapêutico , Política Organizacional , Pneumonia Viral/imunologia , Quarentena/organização & administração , Astronave , Texas , Estados Unidos , United States National Aeronautics and Space Administration
9.
Ophthalmologe ; 117(8): 740-745, 2020 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-32519116

RESUMO

BACKGROUND: Ocular changes in astronauts, particularly the spaceflight associated neuro-ocular syndrome (SANS), pose a medical challenge for which no suitable preventive measures exist. During long-duration spaceflight missions, e.g. to the Moon and Mars, SANS and radiation-induced cataract could affect the health and performance of crews and jeopardize the success of missions. Mechanistic studies and development of preventive measures require suitable terrestrial models. OBJECTIVE: Overview on the most recent research and future plans in space medicine. MATERIAL AND METHODS: Search for relevant publications using PubMed. RESULTS: Bed rest studies at the German Aerospace Center (DLR) demonstrated that strict bed rest in a -6° head down tilt position reproduces changes just like SANS on Earth. This model including creation of optic disc edema is applied in human studies testing influences of artificial gravity through short arm centrifugation as a preventive method. The unique research facility :envihab provides the opportunity to also simulate the ambient conditions of the International Space Station during bed rest studies. CONCLUSION: Future head down tilt bed rest studies will serve to systematically test preventive measures for SANS. Similar investigations would be difficult to realize under real space conditions. Through close collaboration between space medicine and terrestrial ophthalmology, this research can benefit patients on Earth.


Assuntos
Astronautas , Voo Espacial , Olho , Humanos , Papiledema , Visão Ocular
11.
PLoS One ; 15(4): e0231838, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348348

RESUMO

The International Space Station (ISS) is a complex built environment physically isolated from Earth. Assessing the interplay between the microbial community of the ISS and its crew is important for preventing biomedical and structural complications for long term human spaceflight missions. In this study, we describe one crewmember's microbial profile from body swabs of mouth, nose, ear, skin and saliva that were collected at eight different time points pre-, during and post-flight. Additionally, environmental surface samples from eight different habitable locations in the ISS were collected from two flights. Environmental samples from one flight were collected by the crewmember and samples from the next flight were collected after the crewmember departed. The microbial composition in both environment and crewmember samples was measured using shotgun metagenomic sequencing and processed using the Livermore Metagenomics Analysis Toolkit. Ordination of sample to sample distances showed that of the eight crew body sites analyzed, skin, nostril, and ear samples are more similar in microbial composition to the ISS surfaces than mouth and saliva samples; and that the microbial composition of the crewmember's skin samples are more closely related to the ISS surface samples collected by the crewmember on the same flight than ISS surface samples collected by other crewmembers on different flights. In these collections, species alpha diversity in saliva samples appears to decrease during flight and rebound after returning to Earth. This is the first study to compare the ISS microbiome to a crewmember's microbiome via shotgun metagenomic sequencing. We observed that the microbiome of the surfaces inside the ISS resemble those of the crew's skin. These data support future crew and ISS microbial surveillance efforts and the design of preventive measures to maintain crew habitat onboard spacecraft destined for long term space travel.


Assuntos
Astronautas , Sistemas Ecológicos Fechados , Microbiota/genética , Voo Espacial/instrumentação , Astronave , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Monitoramento Ambiental/métodos , Humanos , Metagenoma/genética , Saliva/microbiologia , Pele/microbiologia , Fatores de Tempo
13.
Radiology ; 295(3): 640-648, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32286194

RESUMO

Background Astronauts on long-duration spaceflight missions may develop changes in ocular structure and function, which can persist for years after the return to normal gravity. Chronic exposure to elevated intracranial pressure during spaceflight is hypothesized to be a contributing factor, however, the etiologic causes remain unknown. Purpose To investigate the intracranial effects of microgravity by measuring combined changes in intracranial volumetric parameters, pituitary morphologic structure, and aqueductal cerebrospinal fluid (CSF) hydrodynamics relative to spaceflight and to establish a comprehensive model of recovery after return to Earth. Materials and Methods This prospective longitudinal MRI study enrolled astronauts with planned long-duration spaceflight. Measures were conducted before spaceflight followed by 1, 30, 90, 180, and 360 days after landing. Intracranial volumetry and aqueductal CSF hydrodynamics (CSF peak-to-peak velocity amplitude and aqueductal stroke volume) were quantified for each phase. Qualitative and quantitative changes in pre- to postflight (day 1) pituitary morphologic structure were determined. Statistical analysis included separate mixed-effects models per dependent variable with repeated observations over time. Results Eleven astronauts (mean age, 45 years ± 5 [standard deviation]; 10 men) showed increased mean volumes in the brain (28 mL; P < .001), white matter (26 mL; P < .001), mean lateral ventricles (2.2 mL; P < .001), and mean summated brain and CSF (33 mL; P < .001) at postflight day 1 with corresponding increases in mean aqueductal stroke volume (14.6 µL; P = .045) and mean CSF peak-to-peak velocity magnitude (2.2 cm/sec; P = .01). Summated mean brain and CSF volumes remained increased at 360 days after spaceflight (28 mL; P < .001). Qualitatively, six of 11 (55%) astronauts developed or showed exacerbated pituitary dome depression compared with baseline. Average midline pituitary height decreased from 5.9 to 5.3 mm (P < .001). Conclusion Long-duration spaceflight was associated with increased pituitary deformation, augmented aqueductal cerebrospinal fluid (CSF) hydrodynamics, and expansion of summated brain and CSF volumes. Summated brain and CSF volumetric expansion persisted up to 1 year into recovery, suggesting permanent alteration. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Lev in this issue.


Assuntos
Astronautas , Encéfalo/diagnóstico por imagem , Pressão do Líquido Cefalorraquidiano/fisiologia , Pressão Intracraniana/fisiologia , Imagem por Ressonância Magnética , Voo Espacial , Simulação de Ausência de Peso , Adulto , Aqueduto do Mesencéfalo/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Hipófise/diagnóstico por imagem , Estudos Prospectivos
15.
Sci Rep ; 10(1): 2737, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066765

RESUMO

Astronauts on interplanetary missions - such as to Mars - will be exposed to space radiation, a spectrum of highly-charged, fast-moving particles that includes 56Fe and 28Si. Earth-based preclinical studies show space radiation decreases rodent performance in low- and some high-level cognitive tasks. Given astronaut use of touchscreen platforms during training and space flight and given the ability of rodent touchscreen tasks to assess functional integrity of brain circuits and multiple cognitive domains in a non-aversive way, here we exposed 6-month-old C57BL/6J male mice to whole-body space radiation and subsequently assessed them on a touchscreen battery. Relative to Sham treatment, 56Fe irradiation did not overtly change performance on tasks of visual discrimination, reversal learning, rule-based, or object-spatial paired associates learning, suggesting preserved functional integrity of supporting brain circuits. Surprisingly, 56Fe irradiation improved performance on a dentate gyrus-reliant pattern separation task; irradiated mice learned faster and were more accurate than controls. Improved pattern separation performance did not appear to be touchscreen-, radiation particle-, or neurogenesis-dependent, as 56Fe and 28Si irradiation led to faster context discrimination in a non-touchscreen task and 56Fe decreased new dentate gyrus neurons relative to Sham. These data urge revisitation of the broadly-held view that space radiation is detrimental to cognition.


Assuntos
Cognição/efeitos da radiação , Radiação Cósmica , Giro Denteado/efeitos da radiação , Aprendizagem por Associação de Pares/efeitos da radiação , Reconhecimento Visual de Modelos/efeitos da radiação , Reversão de Aprendizagem/efeitos da radiação , Animais , Astronautas , Ciências Biocomportamentais , Cognição/fisiologia , Giro Denteado/fisiologia , Isótopos de Ferro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/citologia , Neurônios/fisiologia , Neurônios/efeitos da radiação , Aprendizagem por Associação de Pares/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Reversão de Aprendizagem/fisiologia , Voo Espacial , Irradiação Corporal Total
16.
PLoS One ; 15(1): e0226434, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31967993

RESUMO

A round-trip human mission to Mars is anticipated to last roughly three years. Spaceflight conditions are known to cause loss of bone mineral density (BMD) in astronauts, increasing bone fracture risk. There is an urgent need to understand BMD progression as a function of spaceflight time to minimize associated health implications and ensure mission success. Here we introduce a nonlinear mathematical model of BMD loss for candidate human missions to Mars: (i) Opposition class trajectory (400-600 days), and (ii) Conjunction class trajectory (1000-1200 days). Using femoral neck BMD data (N = 69) from astronauts after 132-day and 228-day spaceflight and the World Health Organization's fracture risk recommendation, we predicted post-mission risk and associated osteopathology. Our model predicts 62% opposition class astronauts and 100% conjunction class astronauts will develop osteopenia, with 33% being at risk for osteoporosis. This model can help in implementing countermeasure strategies and inform space agencies' choice of crew candidates.


Assuntos
Astronautas/estatística & dados numéricos , Densidade Óssea , Marte , Osteoporose/etiologia , Voo Espacial , Ausência de Peso/efeitos adversos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico
17.
PLoS Pathog ; 16(1): e1008153, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31999804

RESUMO

Human space travel is on the verge of visiting Mars and, in the future, even more distant places in the solar system. These journeys will be also made by terrestrial microorganisms (hitchhiking on the bodies of astronauts or on scientific instruments) that, upon arrival, will come into contact with new planetary environments, despite the best measures to prevent contamination. These microorganisms could potentially adapt and grow in the new environments and subsequently recolonize and infect astronauts. An even more challenging situation would be if truly alien microorganisms will be present on these solar system bodies: What will be their pathogenic potential, and how would our immune host defenses react? It will be crucial to anticipate these situations and investigate how the immune system of humans might cope with modified terrestrial or alien microbes. We propose several scenarios that may be encountered and how to respond to these challenges.


Assuntos
Equipamentos e Provisões/microbiologia , Interações Hospedeiro-Patógeno , Sistema Imunitário/imunologia , Astronautas , Exobiologia , Meio Ambiente Extraterreno , Humanos , Voo Espacial , Astronave
18.
Aerosp Med Hum Perform ; 91(2): 91-97, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31980047

RESUMO

INTRODUCTION: Spaceflight Associated Neuro-ocular Syndrome (SANS) results from long-duration spaceflight and presents with a constellation of signs (e.g., optic disc edema, choroidal folds, globe flattening, refractive error shifts, etc.). Optic nerve tortuosity (ONT) has been detected in approximately 47% of astronauts after long-duration spaceflight but has not yet been fully analyzed. This review examines terrestrial ONT in order to better understand how the condition is caused and measured.METHODS: References were identified by PubMed and ScienceDirect searches covering 1955 to October 2018 using the terms "optic nerve tortuosity," "optic nerve kinking," "optic disc torsion," "optic kinking," and "ocular torsion." Additional references were identified by searching relevant articles.RESULTS: ONT measurements have evolved and become more objective. One measure consists of meeting two criteria: 1) lack of optic nerve congruity in >1 coronal section; and 2) subarachnoid space dilation. This "criteria measure" is objective, sensitive, and specific for determining the presence of tortuosity. Another measure is the tortuosity index, which offers additional benefits by measuring the degree of ONT, including the potential to track changes over time. There are numerous terrestrial ONT causes, including intracranial hypertension, hydrocephalus, Chiari malformation, neurofibromatosis, glaucoma, and progeria, among others.DISCUSSION: To accurately measure ONT, it is crucial to adhere to objective, standardized techniques. The tortuosity index offers the potential to measure intraindividual change in ONT. Among the varied conditions associated with ONT, one commonality is pressure change. The impact of intracranial pressure on the vascular system and vice versa may offer insight into what is occurring in space.Scott RA, Tarver WJ, Brunstetter TJ, Urquieta E. Optic nerve tortuosity on Earth and in space. Aerosp Med Hum Perform. 2020; 91(2):91-97.


Assuntos
Astronautas , Nervo Óptico/fisiopatologia , Papiledema/fisiopatologia , Voo Espacial , Transtornos da Visão/fisiopatologia , Medicina Aeroespacial , Humanos
19.
Aerosp Med Hum Perform ; 91(1): 41-45, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31852573

RESUMO

INTRODUCTION: There are knowledge gaps in spaceflight pharmacology with insufficient in-flight data to inform future planning. This effort directly addressed in-mission medication use and also informed open questions regarding spaceflight-associated changes in pharmacokinetics (PK) and/or pharmacodynamics (PD).METHODS: An iOS application was designed to collect medication use information relevant for research from volunteer astronaut crewmembers: medication name, dose, dosing frequency, indication, perceived efficacy, and side effects. Leveraging the limited medication choices aboard allowed a streamlined questionnaire. There were 24 subjects approved for participation.RESULTS: Six crewmembers completed flight data collection and five completed ground data collection before NASA's early study discontinuation. There were 5766 medication use entries, averaging 20.6 ± 8.4 entries per subject per flight week. Types of medications and their indications were similar to previous reports, with sleep disturbances and muscle/joint pain as primary drivers. Two subjects treated prolonged skin problems. Subjects also used the application in unanticipated ways: to note drug tolerance testing or medication holiday per research protocols, and to share data with flight surgeons. Subjects also provided usability feedback on application design and implementation.DISCUSSION: The volume of data collected (20.6 ± 8.4 entries per subject per flight week) is much greater than was collected previously (<12 per person per entire mission), despite user criticisms regarding app usability. It seems likely that improvements in a software-based questionnaire application could result in a robust data collection tool that astronauts find more acceptable, while simultaneously providing researchers and clinicians with useful data.Wotring VE, Smith LK. Dose tracker application for collecting medication use data from International Space Station crew. Aerosp Med Hum Perform. 2020; 91(1):41-45.


Assuntos
Astronautas , Tratamento Farmacológico/estatística & dados numéricos , Aplicativos Móveis , Voo Espacial , Estudos de Coortes , Humanos , Fatores de Tempo
20.
Am J Hematol ; 95(3): 267-273, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31816115

RESUMO

The effects of space travel have renewed importance with space tourism and plans for long-term missions to the moon and Mars. The study of space anemia is limited by the availability of subjects and extreme conditions. An approach using the accumulated data on human space flight may characterize space anemia. A total of 17 336 hemoglobin (Hb) concentration measures from 721 space missions and controls were used to study acute and long-term effects of duration of exposure to space on Hb decrement. Nearly half of astronauts (48%) landing after long duration missions were anemic. Returning to Earth revealed Hb decrements whose magnitude and time to recover were dependent on exposure to space: -0.61 g/dL (4%), -0.82 g/dL (5%) and -1.66 g/dL (11%) of preflight Hb for mean exposure to space of 5.4, 11.5, and 145 days, respectively. Astronauts returning from a mean 5.4 days in space took 24 days to return to preflight Hb while astronauts 11.5 to 145 days in space took 49 days. Negative effects of microgravity on Hb persisted throughout female and male astronauts' terrestrial lives (-0.001 and -0.002 mg/dL Hb respectively) for every day spent in space (both P < .05). The negative effect of exposure to space was not overcome by a statistically significant effect of being an astronaut compared to controls. Exposure to space showed a dose-response relationship with acute and chronic Hb decrements. Space anemia contributes to the deconditioning of astronauts returning to Earth, and needs to be considered for space travel to other planets, space tourism and for the care of bedridden patients who present similar changes as astronauts.


Assuntos
Anemia/sangue , Astronautas , Hemoglobinas/metabolismo , Voo Espacial , Ausência de Peso/efeitos adversos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...