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1.
Rhinology ; 61(1): 12-23, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36323438

RESUMEN

BACKGROUND: Chemosensory dysfunction (CD) has been reported as a common symptom of SARS-CoV-2 infection, but it is not well understood whether and for how long changes of smell, taste and chemesthesis persist in infected individuals. METHODOLOGY: Unselected adult residents of the German federal state of Schleswig-Holstein with Polymerase Chain Reaction (PCR)-test-confirmed SARS-CoV-2 infection were invited to participate in this large cross-sectional study. Data on the medical history and subjective chemosensory function of participants were obtained through questionnaires and visual analogue scales (VAS). Olfactory function (OF) was objectified with the Sniffin Sticks test (SST), including threshold (T), discrimination (D) and identification (I) test as well as summarized TDI score, and compared to that in healthy controls. Gustatory function (GF) was evaluated with the suprathreshold taste strips (TS) test, and trigeminal function was tested with an ampoule containing ammonia. RESULTS: Between November 2020 and June 2021, 667 infected individuals (mean age: 48.2 years) were examined 9.1 months, on average, after positive PCR testing. Of these, 45.6% had persisting subjective olfactory dysfunction (OD), 36.2% had subjective gustatory dysfunction (GD). Tested OD, tested GD and impaired trigeminal function were observed in 34.6%, 7.3% and 1.8% of participants, respectively. The mean TDI score of participants was significantly lower compared to healthy subjects. Significant associations were observed between subjective OD and GD, and between tested OD and GD. CONCLUSION: Nine months after SARS-CoV-2 infection, OD prevalence is significantly increased among infected members of the general population. Therefore, OD should be included in the list of symptoms collectively defining Long-COVID.


Asunto(s)
COVID-19 , Trastornos del Olfato , Adulto , Humanos , Persona de Mediana Edad , Estudios Transversales , Trastornos del Olfato/epidemiología , Trastornos del Olfato/etiología , Trastornos del Olfato/diagnóstico , SARS-CoV-2 , Síndrome Post Agudo de COVID-19 , Olfato , Trastornos del Gusto/epidemiología , Trastornos del Gusto/etiología
2.
Science ; 356(6342): 1069-1072, 2017 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-28596364

RESUMEN

The origin of cometary matter and the potential contribution of comets to inner-planet atmospheres are long-standing problems. During a series of dedicated low-altitude orbits, the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) on the Rosetta spacecraft analyzed the isotopes of xenon in the coma of comet 67P/Churyumov-Gerasimenko. The xenon isotopic composition shows deficits in heavy xenon isotopes and matches that of a primordial atmospheric component. The present-day Earth atmosphere contains 22 ± 5% cometary xenon, in addition to chondritic (or solar) xenon.

3.
Nature ; 526(7575): 678-81, 2015 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-26511578

RESUMEN

The composition of the neutral gas comas of most comets is dominated by H2O, CO and CO2, typically comprising as much as 95 per cent of the total gas density. In addition, cometary comas have been found to contain a rich array of other molecules, including sulfuric compounds and complex hydrocarbons. Molecular oxygen (O2), however, despite its detection on other icy bodies such as the moons of Jupiter and Saturn, has remained undetected in cometary comas. Here we report in situ measurement of O2 in the coma of comet 67P/Churyumov-Gerasimenko, with local abundances ranging from one per cent to ten per cent relative to H2O and with a mean value of 3.80 ± 0.85 per cent. Our observations indicate that the O2/H2O ratio is isotropic in the coma and does not change systematically with heliocentric distance. This suggests that primordial O2 was incorporated into the nucleus during the comet's formation, which is unexpected given the low upper limits from remote sensing observations. Current Solar System formation models do not predict conditions that would allow this to occur.


Asunto(s)
Meteoroides , Oxígeno/análisis , Monóxido de Carbono/análisis , Medio Ambiente Extraterrestre/química , Hielo/análisis , Nitrógeno/análisis , Oxígeno/efectos de la radiación , Fotólisis , Sistema Solar/química , Nave Espacial , Agua/análisis
4.
Science ; 348(6231): 232-5, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25791084

RESUMEN

Molecular nitrogen (N2) is thought to have been the most abundant form of nitrogen in the protosolar nebula. It is the main N-bearing molecule in the atmospheres of Pluto and Triton and probably the main nitrogen reservoir from which the giant planets formed. Yet in comets, often considered the most primitive bodies in the solar system, N2 has not been detected. Here we report the direct in situ measurement of N2 in the Jupiter family comet 67P/Churyumov-Gerasimenko, made by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer aboard the Rosetta spacecraft. A N2/CO ratio of (5.70 ± 0.66) × 10(-3) (2σ standard deviation of the sampled mean) corresponds to depletion by a factor of ~25.4 ± 8.9 as compared to the protosolar value. This depletion suggests that cometary grains formed at low-temperature conditions below ~30 kelvin.

5.
Science ; 347(6220): aaa0276, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25613892

RESUMEN

Comets contain the best-preserved material from the beginning of our planetary system. Their nuclei and comae composition reveal clues about physical and chemical conditions during the early solar system when comets formed. ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) onboard the Rosetta spacecraft has measured the coma composition of comet 67P/Churyumov-Gerasimenko with well-sampled time resolution per rotation. Measurements were made over many comet rotation periods and a wide range of latitudes. These measurements show large fluctuations in composition in a heterogeneous coma that has diurnal and possibly seasonal variations in the major outgassing species: water, carbon monoxide, and carbon dioxide. These results indicate a complex coma-nucleus relationship where seasonal variations may be driven by temperature differences just below the comet surface.

6.
Science ; 347(6220): 1261952, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25501976

RESUMEN

The provenance of water and organic compounds on Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the deuterium-to-hydrogen (D/H) ratios in the reservoirs for comets and Earth's oceans. Here, we report the direct in situ measurement of the D/H ratio in the Jupiter family comet 67P/Churyumov-Gerasimenko by the ROSINA mass spectrometer aboard the European Space Agency's Rosetta spacecraft, which is found to be (5.3 ± 0.7) × 10(-4)­that is, approximately three times the terrestrial value. Previous cometary measurements and our new finding suggest a wide range of D/H ratios in the water within Jupiter family objects and preclude the idea that this reservoir is solely composed of Earth ocean-like water.

7.
Artículo en Inglés | MEDLINE | ID: mdl-21177087

RESUMEN

Dietary intake of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) results in cardioprotective benefits. However, the cellular and physiological bases for these benefits remain unclear. We hypothesized that EPA and DHA treatments would interfere with collagen-mediated platelet signaling. Thirty healthy volunteers received 28 days of 3.4 g/d EPA+DHA with and without a single dose of aspirin. Clinical hematologic parameters were then measured along with assays of collagen-stimulated platelet activation and protein phosphorylation. Omega-3 therapy led to a small but significant reduction in platelets (6.3%) and red blood cells (1.7%), but did not impair clinical time-to-closure assays. However, collagen-mediated platelet signaling events of integrin activation, α-granule secretion, and phosphatidylserine exposure were all reduced by roughly 50% after omega-3 incorporation, and collagen-induced tyrosine phosphorylation was significantly impaired. The diminished platelet response to collagen may account for some of the cardioprotective benefits provided by DHA and EPA.


Asunto(s)
Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Colágeno/metabolismo , Ácidos Grasos Omega-3/farmacología , Transducción de Señal , Adulto , Estudios de Cohortes , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Docosahexaenoicos/farmacología , Ácido Eicosapentaenoico/administración & dosificación , Ácido Eicosapentaenoico/farmacología , Ácidos Grasos Omega-3/administración & dosificación , Humanos , Persona de Mediana Edad , Recuento de Plaquetas
8.
Science ; 268(5213): 1013-6, 1995 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-7754379

RESUMEN

Measurements with the Energetic Particle Composition instrument (EPAC) aboard Ulysses show particles from near the ecliptic that were apparently accelerated by shocks associated with a corotating interaction region. The particles were detected together with the shocks and even when shocks no longer arrived at Ulysses up to -65 degrees of heliographic latitude but not beyond. Particles could have reached these latitudes along magnetic fields; such connections to the outer lower latitude heliosphere evidently do not exist above that latitude. The accelerated streams have composition similar to solar wind abundances, no dispersion, and a net inward anisotropy. The underlying composition between the recurrent stream is similar to the anomalous component of cosmic rays. The channel sensitive to high-energy protons (> 230 megaelectron volts) shows a 26-day variation of the flux superimposed on the heliospheric modulation of galactic ions.


Asunto(s)
Medio Ambiente Extraterrestre , Sistema Solar , Aceleración , Iones , Rotación , Nave Espacial
9.
Eur Heart J ; 14(1): 106-12, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8432277

RESUMEN

The endogenous activity of the local renin-angiotensin system (RAS) and the anti-ischaemic properties of captopril were investigated in electrically driven rabbit Langendorff hearts (constant pressure: 70 cmH2O, Tyrode solution, Ca2+ 1.8 mmol.l-1). Cumulative concentration-response curves showed no significant difference (P > 0.05) between the reduction of the global coronary flow (CF) by exogenous angiotensin-I or angiotensin-II (EC50 = 10(-10) mol.l-1). It is concluded that the local RAS in isolated rabbit hearts is highly sensitive, whereas its endogenous activity is very low due to very low endogenous angiotensin-I content. Myocardial ischaemia (MI) was induced by the occlusion of a left coronary artery branch and MI was quantified from NADH surface fluorescence photography. MI was significantly enlarged (+35%) (P < 0.05) by exogenous angiotensin-I (6 x 10(-9) mol.l-1). The reduction in CF and the increment in MI by angiotensin-I could be completely prevented by adding captopril at a low concentration (10(-6) mol.l-1) to the perfusion buffer. In the absence of exogenous angiotensin-I, captopril alone (10(-6) mol.l-1) neither significantly enhanced CF (P > 0.05), nor diminished MI (P > 0.05), supporting the finding of very low endogenous activity of the local RAS in this model. We, moreover, conclude that at a low concentration (10(-6) mol.l-1) captopril does not possess direct cardioprotective properties independent of its ACE inhibiting action.


Asunto(s)
Angiotensina I/antagonistas & inhibidores , Captopril/farmacología , Circulación Coronaria/efectos de los fármacos , Isquemia Miocárdica/fisiopatología , Angiotensina I/farmacología , Animales , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Circulación Coronaria/fisiología , Relación Dosis-Respuesta a Droga , Masculino , Reperfusión Miocárdica , NAD/metabolismo , Técnicas de Cultivo de Órganos , Conejos , Sistema Renina-Angiotensina/efectos de los fármacos , Sistema Renina-Angiotensina/fisiología
10.
Science ; 257(5076): 1553-7, 1992 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-17776167

RESUMEN

Observations of ions and electrons of probable Jovian origin upstream of Jupiter were observed after a corotating interplanetary particle event. During the passage of Ulysses through the Jovian bow shock, magnetopause, and outer magnetosphere, the fluxes of energetic particles were surprisingly low. During the passage through the "middle magnetosphere," corotating fluxes were observed within the current sheet near the jovimagnetic equato. During the outbound pass, fluxes were variably directed; in the later part of the flyby, they were probably related to high-latitude phenomena.

11.
Science ; 237(4815): 626-8, 1987 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-17758562

RESUMEN

In situ measurements of the composition and spatial distribution of heavy thermal positive ions in the coma of comet Halley were made with the heavy-ion analyzer RPA2-PICCA aboard the Giotto spacecraft. Above 50 atomic mass units an ordered series of mass peaks centered at 61, 75, 91, and 105 atomic mass units were observed. Each peak appears to be composed of three or more closely spaced masses. The abundances decrease and the dissociation rates increase smoothly with increasing mass. These observations suggest the presence of chain molecules that are enriched in carbon, oxygen, and hydrogen, such as polyoxymethylene (polymerized formaldehyde), in comet Halley.

12.
Rev Sci Instrum ; 49(10): 1435, 1978 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18698972

RESUMEN

Design and test of a new magnetic electron spectrometer with excellent angular and rather small energy resolution is described. The system is specifically designed for a space flight application to analyze the angular distribution of energetic electrons. Incident electrons with energies between 15 and 270 keV are focused with respect to the direction of incidence. Reasonable directional focusing is obtained over an angular range of 60 degrees with a resolution of 5 degrees. This magnetic electron spectrometer is part of the energetic particle instrument (EPI) developed for the European Space Agency (ESA) GEOS program. GEOS-1 was launched on April 20, 1977, and injected into a 12-h orbit. The instrument has worked successfully since the switch-on-phase in the beginning of May 1977.

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