Atmospheric escape has been detected from the exoplanet HD 209458b through transit observations of the hydrogen Lyman-α line. Here we present spectrally resolved Lyman-α transit observations of the ...exoplanet HD 189733b at two different epochs. These HST/STIS observations show for the first time that there are significant temporal variations in the physical conditions of an evaporating planetary atmosphere. While atmospheric hydrogen is not detected in the first epoch observations, it is observed at the second epoch, producing a transit absorption depth of 14.4 ± 3.6% between velocities of −230 to −140 km s-1. Contrary to HD 209458b, these high velocities cannot arise from radiation pressure alone and require an additional acceleration mechanism, such as interactions with stellar wind protons. The observed absorption can be explained by an atmospheric escape rate of neutral hydrogen atoms of about 109 g s-1, a stellar wind with a velocity of 190 km s-1 and a temperature of ~105 K. An X-ray flare from the active star seen with Swift/XRT 8 h before the second-epoch observation supports the idea that the observed changes within the upper atmosphere of the planet can be caused by variations in the stellar wind properties, or by variations in the stellar energy input to the planetary escaping gas (or a mix of the two effects). These observations provide the first indication of interaction between the exoplanet’s atmosphere and stellar variations.
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Observations of transits of the hot giant exoplanet HD 189733b in the unresolved H i Lyman-α line show signs of hydrogen escaping the upper atmosphere of the planet. New resolved Lyman-α observations ...obtained with the STIS spectrograph onboard the Hubble Space Telescope in April 2010 and September 2011 confirmed that the planet is evaporating, and furthermore discovered significant temporal variations in the physical conditions of its evaporating atmosphere. Here we present a detailed analysis of the September 2011 observations of HD 189733b, when an atmospheric signature was detected. We present specific methods to find and characterize this absorption signature of escaping hydrogen in the Lyman-α line, and to calculate its false-positive probability, found to be 3.6%. Taking advantage of the spectral resolution and high sensitivity of the STIS spectrograph, we also present new results on temporal and spectro-temporal variability of this absorption feature. We also report the observation of HD 189733b in other lines (Si iii at 1206.5 Å, N v at 1240 Å). Variations in these lines could be explained either by early occultation by a bow-shock rich in highly ionized species, or by stellar variations.
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Abstract Objectives Common Variable Immunodeficiency Disorders (CVID) and Large Granular Lymphocytes leukemia (LGLL) exhibit diverse clinical manifestations including infections, dysimmunity, and ...lymphoproliferation. Recent decades have seen the discovery of new genes in the lymphopoiesis pathway, such as JAK–STAT. This case series supplemented by a literature review aims to describe clinical and biological characteristics of patients with both CIVD and LGLL. Methodology Patients were included through a call for comments to French and Belgian centers and through a literature review via PubMed. Clinical characteristics were compared to two large French cohort involving CVID and LGLL patients. Results Twelve patients were included. In all cases, CVID precedes LLGL (median diagnosis delay for LLGL was 7 years). Most cases presented with splenomegaly and autoimmune cytopenia. Ten out of 12 patients underwent splenectomy during follow up. Conclusions Patients with LGLL and CVID differ from patients without immune deficiency in term of clinical presentation and prognosis. We suggest CVID may act as a trigger of LGL lymphocytosis, due to endogenous and exogenous antigenic pressure leading to the selection of a dominant LGL clone and stimulation of the JAK–STAT pathway. The role of splenomegaly and splenectomy in LGLL onset warrant further investigation in future studies.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Progressive fibrosing interstitial lung disease (ILD) is rarely associated with antineutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV). This study focused on the outcomes of ILD ...patients with associated AAV (AAV–ILD).
AAV–ILD (cases: microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA) with ILD) were compared to AAV patients without ILD (controls). ILD was defined as a usual interstitial pneumonia (UIP) or non-specific interstitial pneumonia (NSIP) pattern. Two controls were matched to each case for age (>or ≤65 years), ANCA status (PR3-or MPO-positive) and creatininemia (≥or <150 μmol/L).
Sixty-two cases (89% MPO-ANCA+) were included. Median age at AAV diagnosis was 66 years. ILD (63% UIP), was diagnosed before (52%) or simultaneously (39%) with AAV. Cases versus 124 controls less frequently had systemic vasculitis symptoms. One-, 3- and 5-year overall survival rates, respectively, were: 96.7%, 80% and 66% for cases versus 93.5%, 89.6% and 83.8% for controls (p = 0.008). Multivariate analyses retained age >65 years (hazard ratio (HR) 4.54; p < 0.001), alveolar haemorrhage (HR 2.25; p = 0.019) and UIP (HR 2.73; p = 0.002), but not immunosuppressant use, as factors independently associated with shorter survival.
For AAV–ILD patients, only UIP was associated with poorer prognosis. Immunosuppressants did not improve the AAV–ILD prognosis. But in analogy to idiopathic pulmonary fibrosis, anti-fibrosing agents might be useful and should be assessed in AAV–ILD patients with a UIP pattern.
•Progressive fibrosing interstitial lung disease is a rare comorbidity of MPO-vasculitis.•This condition is associated with shorter survival when it has a CT-scan UIP pattern.•Immunosuppressants did not improve the prognosis of these patients.•Our results support the evaluation of anti-fibrotic drugs in this condition.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
7.
Chemical and sensory studies of antioxidant-treated beef St Angelo, A.J. (USDA, ARS, Southern Regional Research Center, New Orleans, LA); Crippen, K.L; Dupuy, H.P ...
Journal of food science,
November 1990, Volume:
55, Issue:
6
Journal Article
Peer reviewed
Ground beef patties treated with metal chelators, free radical scavengers, rosemary and sodium alginate were examined by chemical (TBARS and gas chromatography) and sensory means in regard to ...warmed-over flavor (WOF). A highly trained analytical sensory panel evaluated the patties for desirable descriptors, such as cooked beef brothy (CBB) and for WOF descriptors, painty and cardboardy. Results showed many of the compounds retarded lipid oxidation when judged by chemical means, but not all affected development of WOF when judged by sensory means since CBB values decreased and WOF descriptors increased. The free radical scavengers appeared overall the most effective inhibitors of WOF
Les leucémies myélomonocytaires chroniques (LMMC) partagent les caractéristiques des syndromes myélodysplasiques et myéloprolifératifs. Elles s’associent dans 20 % des cas à des manifestations ...auto-inflammatoires ou auto-immunes (MAI). Le profil mutationnel des LMMC est riche, plus de 90 % des patients sont porteurs d’au moins une mutation. Récemment, il a été décrit le syndrome VEXAS, lié à une mutation UBA1, responsable d’anomalies hématologiques et de phénomènes inflammatoires. Dans l’étude originale, 6 des 25 patients étaient atteints d’un syndrome myélodysplasique. Nous avons recherché si les LMMC, avec ou sans MAI, présentaient des mutations UBA1.
Il s’agit d’une étude rétrospective monocentrique d’une cohorte de patients atteints, entre janvier 1999 et décembre 2019, de LMMC sans et avec MAI, chez qui un séquençage de 64 gènes fréquemment altérés dans cette hémopathie, et un séquençage d’UBA1, ont été réalisé.
Un total de 108 patients a eu un séquençage, dont 23 patients atteints d’une ou plusieurs MAI. Les patients avec ou sans MAI étaient comparables, y compris pour la répartition d’âge, de sexe, d’anémie macrocytaire et de thrombopénie. Les MAI comprenaient notamment 9 dermatoses, 9 arthrites, 6 péricardites, et 3 vascularites systémiques. Les MAI précédaient la LMMC dans 20 % des cas, et étaient diagnostiquées de manière concomitante (moins de 6 mois d’écart) dans 52 % des cas. Concernant l’atteinte cutanée, 4 patients avaient une dermatose neutrophilique, 3 des lésions papulonodulaires inflammatoires apparues en parallèle du diagnostic de LMMC, 1 avait un pemphigus vulgaire et le dernier une vascularite cutanée. Les arthrites inflammatoires concernaient à chaque fois les grosses articulations périphériques. Tous les patients avec atteinte cardiaque présentaient un épanchement péricardique d’allure aiguë, conduisant à 5 drainages en urgence, et 4 de ces péricardites sont apparues en parallèle d’une majoration de la monocytose, jusqu’à 20 G/L. À propos des vascularites, 1 patient avait une maladie de Horton, 1 autre une péri-artérite noueuse et 1 autre des thromboses artérielles multiples responsables d’infarctus splénique, rénal et cérébral. Le screening moléculaire des 108 patients révélait une prédominance de mutations TET2 (71 %), SRSF2 (46 %), et ASXL1 (42 %). Il n’y avait pas de différence significative du statut mutationnel entre les LMMC avec ou sans MAI. Aucun patient de la cohorte n’avait de mutations UBA1, y compris ceux avec MAI. Les myélogrammes n’avaient pas révélé de vacuoles dans les précurseurs myéloïdes ou érythroïdes.
Parmi nos patients, la prévalence des vascularites systémiques était faible, à 12 %. Nous n’avions aucun cas de polychondrite atrophiante. Ces deux MAI paraissent relativement fréquentes dans les syndromes VEXAS. Les phénotypes différents de MAI entre notre cohorte et les patients atteints de VEXAS pourraient traduire des mécanismes inflammatoires différents, indépendant des mutations UBA1. L’importante charge mutationnelle des LMMC conduit à de multiples combinaisons de mutations, pouvant survenir à différentes étapes de l’hématopoïèse, responsables des différents phénotypes hématologiques. Ces différentes combinaisons de mutations pourraient être à l’origine des différentes phénotypes de MAI. TET2 aurait un rôle dans la tolérance immune, et serait muté de manière prépondérante en cas de syndromes myélodysplasiques avec MAI plutôt que sans. De même, SRSF2, ASXL1 ou RUNX1 auraient un rôle dans la régulation inflammatoire. À notre connaissance, aucune mutation UBA1 n’a été jusqu’alors décrite chez des patients atteints de LMMC.
Les mécanismes inflammatoires responsables de MAI dans les LMMC ne semblent pas liés aux mutations UBA1, et pourraient dépendre du profil mutationnel des LMMC. L’étude dédiée du profil cytokinique selon le statut mutationnel des LMMC pourrait aider à expliquer les phénotypes variables de MAI.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Enhanced atrial natriuretic factor (ANF) production by the heart is related to hemodynamic overload, cardiac growth, and hypertrophy. The heart is one of the most affected organs during Trypanosoma ...cruzi infection. We tested the hypothesis that myocarditis produced by parasite infection alters the natriuretic peptide system by investigating the behavior of plasma ANF during the acute and chronic stages of T. cruzi infection in rats. Sprague-Dawley rats were infected with T. cruzi clone Sylvio-X10/7. Cardiac morphology showed damage to myocardial cells and lymphocyte infiltration in the acute phase; and fibrosis and cell atrophy in the chronic period. Plasma ANF levels (radioimmunoassay) were significantly higher in acute (348 ± 40 vs. 195 ± 36 pg/ml, P < 0.05, n = 17) and chronic T. cruzi myocarditis (545 ± 81 vs. 229 ± 38 pg/ml, P < 0.001, n = 11) than in their respective controls (n = 10 and 14). Rats in the chronic phase also showed higher levels than rats in the acute phase (P < 0.01). The damage of myocardial cells produced by the parasite and the subsequent inflammatory response could be responsible for the elevation of plasma ANF during the acute period of T. cruzi infection. The highest plasma ANF levels found in chronically infected rats could be derived from the progressive failure of cardiac function.
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A study evaluated and compared data obtained from chemical, instrumental, and sensory analyses in samples of raw, fresh-cooked, and recooked stored beef muscle. Characteristic descriptors attributed ...to the warmed-over beef included rancid, stale, metallic, and "cardboardy." While gas chromatographic analysis did not detect volatiles commonly associated with lipid oxidation, total volatiles and 2 specific volatiles (hexanal and 2,3-octanedione) correlated with the adverse sensory scores and with 2-thiobartituric acid values. Chromatograms and relative levels of compounds identified are included. (wz)
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