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1.
Front Med Technol ; 6: 1287851, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39036350

RESUMO

Introduction: With current technology, ultrasound imaging in remote conditions, such as the International Space Station, is performed with vocal guidance or using a teleoperated echograph controlled by an expert. Both methods require real-time communications between the novice operator and expert to locate the probe over the appropriate acoustic windows (AW). The current study presents the development and testing of a new augmented reality software (Echo-QR) that would allow novice operators (with no medical imaging background) to correctly locate the ultrasound probe over the AW of interest without expert assistance. Methods: On the first day of the study, the positions of the probe over the AWs were identified for each organ by an expert sonographer and saved in the Echo-QR software. On the second day, the novices independently performed the ultrasound investigation using the Echo-QR software to correctly position the probe over each organ's AW. Results: Using the Echo-QR software, novice operators found the AW in 73 (92%) of the 79 organs. The 2D images acquired by the novices "2D direct image" were acceptable for medical evaluation in 41% of the cases. However, when the "2D direct image" did not show the entire organ, a 3D capture of the volume below the probe was also performed, which allowed for the extraction of the appropriate 2D image "2D/3D image" for medical evaluation in 85% of the cases. Discussion: Therefore, in the absence of real-time communication between an isolated participant and an expert sonographer, novel software (Echo-QR) and automated 3D volume capture can be used to obtain images usable for ultrasound diagnostics.

2.
Astrobiology ; 19(8): 1018-1036, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30653337

RESUMO

We describe the results obtained on a set of organic samples that have been part of the experiment "Photochemistry on the Space Station (PSS)" on the EXPOSE-R2 mission conducted on the EXPOSE-R facility situated outside the International Space Station (ISS). The organic samples were prepared in the Catania laboratory by 200 keV He+ irradiation of N2:CH4:CO icy mixtures deposited at 17 K, on vacuum UV (VUV) transparent MgF2 windows. This organic material contains different chemical groups, including triple CN bonds, that are thought to be of interest for astrobiology. It is widely accepted that materials similar to that produced in the laboratory by ion irradiation of frozen ices could be present in some astrophysical environments such as comets. Once expelled from comets, these materials are exposed to solar radiation during their interplanetary journey. In the young Solar System, some of these processed materials could have reached early Earth and contributed to its chemical and prebiotic evolution. The samples were exposed for 16 months to the unshielded solar UV photons. It was found that, if an interplanetary dust particle (IDP) containing organic material (50% vol) is large enough (>20-30 µm), relevant chemical groups, such as those containing the CN triple bond, can survive for many years (>104 years) in the interplanetary medium.


Assuntos
Poeira/análise , Meio Ambiente Extraterreno , Meteoroides , Compostos Orgânicos/análise , Fotólise , Astronave , Hélio/análise , Análise Espectral , Fatores de Tempo
3.
Adv Space Res ; 42(6): 1072-1079, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22146801

RESUMO

Traveling, living and working in space is now a reality. The number of people and length of time in space is increasing. With new horizons for exploration it becomes more important to fully understand and provide countermeasures to the effects of the space environment on the human body. In addition, space provides a unique laboratory to study how life and physiologic functions adapt from the cellular level to that of the entire organism. Caenorhabditis elegans is a genetic model organism used to study physiology on Earth. Here we provide a description of the rationale, design, methods, and space culture validation of the ICE-FIRST payload, which engaged C. elegans researchers from four nations. Here we also show C. elegans growth and development proceeds essentially normally in a chemically defined liquid medium on board the International Space Station (10.9 day round trip). By setting flight constraints first and bringing together established C. elegans researchers second, we were able to use minimal stowage space to successfully return a total of 53 independent samples, each containing more than a hundred individual animals, to investigators within one year of experiment concept. We believe that in the future, bringing together individuals with knowledge of flight experiment operations, flight hardware, space biology, and genetic model organisms should yield similarly successful payloads.

4.
Adv Space Res ; 27(2): 433-45, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11642305

RESUMO

The study of the influence of weightlessness on fertilization and embryonic development of a vertebrate is of importance in the understanding of basic embryogenesis and in the preparation of the future exploration of space. Accordingly, specific hardware was designed to perform experiments on board the MIR space station with an amphibian vertebrate model, taking into account the biological requirements and the multiple constraints of a long-term mission. This paper describes the biological uses and presents the technological specifications of the device developed under CNES management. The hardware was adapted to and is compatible with biological requirements as confirmed by three experiments performed in space on board the orbital MIR station.


Assuntos
Abrigo para Animais , Modelos Animais , Pleurodeles/embriologia , Voo Espacial/instrumentação , Ausência de Peso , Animais , Desenvolvimento Embrionário , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Fertilização/fisiologia , Masculino , Pleurodeles/crescimento & desenvolvimento , Astronave/instrumentação
5.
Biol Sci Space ; 12(2): 92-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11541888

RESUMO

A large collection of micrometeorites has been recently extracted from Antarctic old blue ice. In the 50 to 100 micrometers size range, the carbonaceous micrometeorites represent 80% of the samples and contain 2% of carbon. They might have brought more carbon to the surface of the primitive Earth than that involved in the present surficial biomass. Amino acids such as "-amino isobutyric acid have been identified in these Antarctic micrometeorites. Enantiomeric excesses of L-amino acids have been detected in the Murchison meteorite. A large fraction of homochiral amino acids might have been delivered to the primitive Earth via meteorites and micrometeorites. Space technology in Earth orbit offers a unique opportunity to study the behaviour of amino acids required for the development of primitive life when they are exposed to space conditions, either free or associated with tiny mineral grains mimicking the micrometeorites. Our objectives are to demonstrate that porous mineral material protects amino acids in space from photolysis and racemization (the conversion of L-amino acids into a mixture of L- and D-molecules) and to test whether photosensitive amino acids derivatives can polymerize in mineral grains under space conditions. The results obtained in BIOPAN-1 and BIOPAN-2 exposure experiments on board unmanned satellite FOTON are presented.


Assuntos
Aminoácidos/química , Carbono/química , Evolução Química , Meteoroides , Voo Espacial/instrumentação , Silicatos de Alumínio/química , Bentonita/química , Argila , Poeira Cósmica/análise , Planeta Terra , Caulim/química , Fotoquímica , Astronave , Estereoisomerismo , Raios Ultravioleta
6.
Astrobiology ; 12(5): 426-35, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22680689

RESUMO

To understand the chemical behavior of organic molecules in the space environment, amino acids and a dipeptide in pure form and embedded in meteorite powder were exposed in the PROCESS experiment in the EXPOSE-E facility mounted on the European Technology Exposure Facility (EuTEF) platform on board the International Space Station (ISS). After exposure to space conditions for 18 months, the samples were returned to Earth and analyzed in the laboratory for reactions caused by solar UV and cosmic radiation. Chemical degradation and possible racemization and oligomerization, the main reactions caused by photochemistry in the vacuum ultraviolet domain (VUV, wavelength range 100-200 nm for photon energy from 6.2 to 12.4 eV) were examined in particular. The molecules were extracted and derivatized by silylation and analyzed by gas chromatograph coupled to a mass spectrometer (GC-MS) to quantify the rate of the degradation of the compounds. Laboratory exposure in several wavelength ranges from UV to VUV was carried out in parallel in the Cologne Deutsches Zentrum für Luft- und Raumfahrt (DLR) Center and Centre de biophysique moléculaire (CBM) laboratories. The results show that resistance to irradiation is a function of the chemical nature of the exposed molecules and the wavelengths of the UV light. The most altered compounds were the dipeptide, aspartic acid, and aminobutyric acid. The most resistant were alanine, valine, glycine, and aminoisobutyric acid. Our results also demonstrate the protective effect of meteorite powder, which reemphasizes the importance of exogenic contribution to the inventory of prebiotic organics on early Earth.


Assuntos
Aminoácidos/química , Astronave , Simulação por Computador , Radiação Cósmica , Evolução Química , Meio Ambiente Extraterreno , Meteoroides , Voo Espacial
7.
J Assoc Off Anal Chem ; 71(3): 542-6, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3391959

RESUMO

A simplified method is described for determining 7 N-methyl carbamates (aldicarb, carbaryl, carbofuran, methiocarb, methomyl, oxamyl, and propoxur) and 3 related metabolites (aldicarb sulfoxide, aldicarb sulfone, and 3-hydroxy carbofuran) in fruits and vegetables. Residues are extracted from crops with methanol; coextractives are then separated by gel permeation chromatography (GPC) or GPC with on-line Nuchar-Celite cleanup for crops with high chlorophyll and/or carotene content (e.g., cabbage and broccoli). Carbamates are separated on a reverse-phase liquid chromatography column, using a methanol-water gradient mobile phase. Separation is followed by postcolumn hydrolysis to yield methylamine, and the formation of a fluorophore with o-phthalaldehyde and 2-mercaptoethanol prior to fluorescence detection. Recovery data were obtained by fortifying 5 different crops (apples, broccoli, cabbages, cauliflower, and potatoes) at 0.05 and 0.5 ppm. Recoveries averaged 93% at both fortification levels except for the very polar aldicarb sulfoxide for which recoveries averaged around 52% at both levels. The coefficient of variation of the method at both levels is less than 5% and the limit of detection, defined at 5 times baseline noise, varies between 5 and 10 ppb, depending on the compound.


Assuntos
Carbamatos , Frutas/análise , Inseticidas/análise , Resíduos de Praguicidas/análise , Verduras/análise , Cromatografia em Gel , Cromatografia Líquida , Indicadores e Reagentes , Espectrometria de Fluorescência
8.
J Assoc Off Anal Chem ; 69(6): 985-9, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3804955

RESUMO

Liquid chromatography combining on-line trace enrichment together with a very selective detection technique is used for the determination of aldicarb, aldicarb sulfoxide, and aldicarb sulfone. Sensitivity is increased by loading a 10 mL volume of ground water on a concentrator column installed in the loop position of a 6-port injection valve. Switching the valves allows the concentrated material to be backflushed onto the analytical column by a methanol-water gradient mobile phase. Separation is followed by post-column hydrolysis to yield methylamine, and formation of a fluorophore with o-phthalaldehyde and 2-mercaptoethanol prior to fluorescence detection. The process requires virtually no sample cleanup and provides good precision on recoveries from different matrixes. Minimum detection limit, defined as 5 times baseline noise, is less than 70 ng/L for the 3 compounds.


Assuntos
Aldicarb/análise , Inseticidas/análise , Poluentes Químicos da Água/análise , Poluentes da Água/análise , Aldicarb/análogos & derivados , Cromatografia Líquida , Indicadores e Reagentes , Oxirredução
9.
J Cell Biochem ; 70(2): 252-67, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9671231

RESUMO

The results of experiments performed in recent years on board facilities such as the Space Shuttle/Spacelab have demonstrated that many cell systems, ranging from simple bacteria to mammalian cells, are sensitive to the microgravity environment, suggesting gravity affects fundamental cellular processes. However, performing well-controlled experiments aboard spacecraft offers unique challenges to the cell biologist. Although systems such as the European 'Biorack' provide generic experiment facilities including an incubator, on-board 1-g reference centrifuge, and contained area for manipulations, the experimenter must still establish a system for performing cell culture experiments that is compatible with the constraints of spaceflight. Two different cell culture kits developed by the French Space Agency, CNES, were recently used to perform a series of experiments during four flights of the 'Biorack' facility aboard the Space Shuttle. The first unit, Generic Cell Activation Kit 1 (GCAK-1), contains six separate culture units per cassette, each consisting of a culture chamber, activator chamber, filtration system (permitting separation of cells from supernatant in-flight), injection port, and supernatant collection chamber. The second unit (GCAK-2) also contains six separate culture units, including a culture, activator, and fixation chambers. Both hardware units permit relatively complex cell culture manipulations without extensive use of spacecraft resources (crew time, volume, mass, power), or the need for excessive safety measures. Possible operations include stimulation of cultures with activators, separation of cells from supernatant, fixation/lysis, manipulation of radiolabelled reagents, and medium exchange. Investigations performed aboard the Space Shuttle in six different experiments used Jurkat, purified T-cells or U937 cells, the results of which are reported separately. We report here the behaviour of Jurkat and U937 cells in the GCAK hardware in ground-based investigations simulating the conditions expected in the flight experiment. Several parameters including cell concentration, time between cell loading and activation, and storage temperature on cell survival were examined to characterise cell response and optimise the experiments to be flown aboard the Space Shuttle. Results indicate that the objectives of the experiments could be met with delays up to 5 days between cell loading into the hardware and initial in flight experiment activation, without the need for medium exchange. Experiment hardware of this kind, which is adaptable to a wide range of cell types and can be easily interfaced to different spacecraft facilities, offers the possibility for a wide range of experimenters successfully and easily to utilise future flight opportunities.


Assuntos
Técnicas de Cultura de Células/métodos , Linfócitos , Monócitos , Ausência de Peso , Transporte Biológico , Técnicas de Cultura de Células/instrumentação , Tamanho Celular , Sobrevivência Celular , Temperatura Baixa , Meios de Cultura , Citocinas/biossíntese , Humanos , Células Jurkat , Ésteres de Forbol/farmacologia , Proteína Quinase C/metabolismo , Voo Espacial , Temperatura , Células Tumorais Cultivadas
10.
FASEB J ; 10(14): 1627-34, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9002555

RESUMO

Protein kinase C (PKC) is an ubiquitous enzyme that mediates intracellular signal transduction in eukaryotes. Jurkat and U937 cells were exposed to microgravity during a Space Shuttle flight and stimulated with a radiolabeled phorbol ester (3H-PDBu) that specifically activates and labels several PKC isoforms. Both the total amount of 3H-PDBu labeling per cell and the relative distribution of labeling between subcellular compartments were altered in microgravity compared to onboard and ground 1 g control samples. The amount of total phorbol ester labeling per cell was increased approximately twofold in microgravity samples when compared with onboard 1 g samples for both cell lines. The subcellular distribution of PKC in the cytosol and nuclear fractions appeared to be correlated with the applied acceleration. In both cell types the relative amount of phorbol ester labeling in the nuclear fraction decreased with applied acceleration, whereas the labeling in cytosolic fraction increased with g level. No significant differences were observed between labeling levels in the membrane fraction in both cell types. Interleukin-1beta synthesis by U937 cells was markedly decreased in microgravity when compared to the onboard 1 g control, suggesting that the observed alterations in PKC distribution may have functional consequences. The results may have important implications for the effect of gravity on cellular signal transduction.


Assuntos
Leucócitos/enzimologia , Proteína Quinase C/metabolismo , Ausência de Peso , Núcleo Celular/enzimologia , Citosol/enzimologia , Humanos , Interleucina-1/metabolismo , Células Jurkat , Leucócitos/citologia , Células Tumorais Cultivadas
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