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Glucosylceramides (GlcCer), glucose-conjugated sphingolipids, are major components of the endomembrane system and plasma membrane in most eukaryotic cells. Yet the quantitative significance and cellular functions of GlcCer are not well characterized in plants and other multi-organ eukaryotes. To address this, we examined Arabidopsis lines that were lacking or deficient in GlcCer by insertional disruption or by RNA interference ( RNAi) suppression of the single gene for GlcCer synthase ( GCS, At2g19880), the enzyme that catalyzes GlcCer synthesis. Null mutants for GCS (designated ' gcs-1') were viable as seedlings, albeit strongly reduced in size, and failed to develop beyond the seedling stage. Heterozygous plants harboring the insertion allele exhibited reduced transmission through the male gametophyte. Undifferentiated calli generated from gcs-1 seedlings and lacking GlcCer proliferated in a manner similar to calli from wild-type plants. However, gcs-1 calli, in contrast to wild-type calli, were unable to develop organs on differentiation media. Consistent with a role for GlcCer in organ-specific cell differentiation, calli from gcs-1 mutants formed roots and leaves on media supplemented with the glucosylated sphingosine glucopsychosine, which was readily converted to GlcCer independent of GCS. Underlying these phenotypes, gcs-1 cells had altered Golgi morphology and fewer cisternae per Golgi apparatus relative to wild-type cells, indicative of protein trafficking defects. Despite seedling lethality in the null mutant, GCS RNAi suppression lines with ≤2% of wild-type GlcCer levels were viable and fertile. Collectively, these results indicate that GlcCer are essential for cell-type differentiation and organogenesis, and plant cells produce amounts of GlcCer in excess of that required for normal development. [ABSTRACT FROM AUTHOR]

The high requirement of the gut for threonine has often been ascribed to the synthesis of mucins, secreted threonine-rich glycoproteins protecting the intestinal epithelium from injury. This requirement could be even greater during intestinal inflammation, when mucin synthesis is enhanced. In this study, we used an animal model to investigate the effects of an acute ileitis on threonine splanchnic fluxes. Eight adult multi-catheterized minipigs were fed with an enteral solution. Four of them were subjected to experimental ileitis involving direct administration of trinitrobenzene sulfonic acid (TNBS) into the ileum (TNBS-treated group) and the other 4 were not treated (control group). Threonine fluxes across the portal-drained viscera (PDV) were quantified with the use of simultaneous i.g. L-[15Nithreonine and iv. L-[U-13C]threonine infusions. Ileal mucosa was sampled for mucin fractional synthesis rate measurement, which was greater in the TNBS-treated group (114 ± 15%/d) than in the control group (61 ± 8%/d) (P= 0.021). The first-pass extraction of dietary threonine by the PDV and liver did not differ between groups and accounted for ∼27 and 10% of the intragastric delivery, respectively. PDV uptake of arterial threonine increased from 25 ± 14 μmol·kg-1· h-1 in the control group to 171 ± 35 μmoI·kg-1· h-1 in the TNBS-treated group (P < 0.001). In conclusion, ileitis increased intestinal mucin synthesis and PDV utilization of threonine from arterial but not luminal supply. This leads to the mobilization of endogenous proteins to meet the increased threonine demand associated with acute intestinal inflammation. [ABSTRACT FROM AUTHOR]

The aerial parts of Salvia hedgeana Dönmez, Salvia huberi Hedge, Salvia pisidica Boiss. & Heldr. ex Bentham. were subjected to hydrodistillation. The obtained essential oils were analyzed both by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The analyses showed that S. hedgeana essential oil consisted of β-pinene (30.0%) as a major component, in addition to 65 identified components, representing 89.9% of the total essential oil. The major component of S. huberi was identified as 1,8-cineole (20.4%), and 76 further components were characterized representing 87.6%. S. pisidica essential oil revealed the occurrence of camphor (21.7%) as the main constituent among another 59 identified components of 76.8% of the total. Furthermore, the biological properties of the analyzed essential oils were tested using the in vivo method on the chorioallantoic membrane (CAM) in order to examine the anti-inflammatory and anti-angiogenic activity as well as possible irritant or toxic side effects. All essential oils tested at a concentration of 100 µg/pellet showed no pronounced anti-inflammatory, angiogenic, or membrane-toxic properties. [ABSTRACT FROM AUTHOR]

The goal of the SunPy project is to facilitate and promote the use and development of community-led, free, and open source data analysis software for solar physics based on the scientific Python environment. The project achieves this goal by developing and maintaining the sunpy core package and supporting an ecosystem of affiliated packages. This paper describes the first official stable release (version 1.0) of the core package, as well as the project organization and infrastructure. This paper concludes with a discussion of the future of the SunPy project. [ABSTRACT FROM AUTHOR]

Nanoarchaeum equitans and Ignicoccus hospitalis represent a unique, intimate association of two archaea. Both form a stable coculture which is mandatory for N. equitans but not for the host I. hospitalis. Here, we investigated interactions and mutual influence between these microorganisms. Fermentation studies revealed that during exponential growth only about 25% of I. hospitalis cells are occupied by N. equitans cells (one to three cells). The latter strongly proliferate in the stationary phase of I. hospitalis, until 80 to 90% of the I. hospitalis cells carry around 10 N. equitans cells. Furthermore, the expulsion of H2S, the major metabolic end product of I. hospitalis, by strong gas stripping yields huge amounts of free N. equitans cells. N. equitans had no influence on the doubling times, final cell concentrations, and growth temperature, pH, or salt concentration ranges or optima of I. hospitalis. However, isolation studies using optical tweezers revealed that infection with N. equitans inhibited the proliferation of individual I. hospitalis cells. This inhibition might be caused by deprivation of the host of cell components like amino acids, as demonstrated by 13C-labeling studies. The strong dependence of N. equitans on I. hospitalis was affirmed by live-dead staining and electron microscopic analyses, which indicated a tight physiological and structural connection between the two microorganisms. No alternative hosts, including other Ignicoccus species, were accepted by N. equitans. In summary, the data show a highly specialized association of N. equitans and I. hospitalis which so far cannot be assigned to a classical symbiosis, commensalism, or parasitism. [ABSTRACT FROM AUTHOR]

Introduction Rendre la vaccination plus « acceptable » par les populations est un enjeu de santé publique. Les épidémies récentes de rougeole sont liées à une baisse de la couverture vaccinale. Dans ce contexte nous développons le concept de la vaccination personnalisée. En effet, la seconde dose (rattrapage) de vaccin rougeole n’est justifiée que pour ceux qui n’ont pas répondu à la première dose. Un nombre élevé d’enfants reçoivent ainsi une dose inutile. Nous avons développé un test rapide destiné à discriminer les personnes justifiant de la seconde dose de vaccin. Nous présentons les performances du premier test rapide mondiale rougeole, entièrement développé en France. Matériels et méthodes Les patients inclus venaient pour un contrôle sérologique (ex : HBV). Leur statut vaccinal était attesté par un carnet de vaccination. Chaque patient a eu un prélèvement capillaire pour réalisation du test rapide. La lecture du résultat (à 15 min) était réalisée de façon indépendante par deux opérateurs. Le prélèvement sanguin veineux a permis la réalisation du test quantitatif de référence (Liaison Measles ® ). Les données ont été analysées à l’aide du logiciel R. Les mesures de sensibilité et spécificité ont été déterminées au seuil de 16,5 UA/mL correspondant à 175 UI/mL, taux protecteur selon l’OMS. Résultats Au total, 139 personnes ont été incluses dans l’étude. Deux jamais vaccinées, 24 avaient reçu une seule dose, 82 avaient reçu 2 doses, 2 avaient reçu 3 doses, 16 avaient présenté une rougeole dans l’enfance et 13 étaient indéterminés. Au total, 79 % des personnes ayant eu une seule dose dans l’enfance et 88 % de ceux ayant eu 2 doses étaient protégés au seuil de 175 UI/mL (taux d’efficacité vaccinale). La sensibilité et la spécificité du test rapide étaient respectivement de 66,7 % (IC 95 % : 58,2 %–75,1 %) et de 96,7 % (90,5 %–100 %), la VPP était de 98,7 % et le rapport de vraisemblance positif et négatif étaient respectivement 12,6 et 0,35 témoignant d’une très forte liaison entre le test rapide et la présence d’IgG (coef Yule : 0,95). Pour les personnes n’ayant reçu qu’une dose de vaccin ( n = 24), 19 avaient un taux d’IgG > 175 UI/mL (79 %) : le test rapide était négatif pour 10 d’entre eux. Cinq (21 %) avaient un taux d’IgG < 175 UI/mL : parmi eux, aucun test rapide n’était positif. Conclusion Le test Biosynex Measles présente des performances techniques prometteuses. Tous les patients non immuns après une dose avaient un test rapide négatif et seraient éligibles pour la seconde dose. Au total, 52 % des patients immunisés après une dose recevraient une seconde dose versus 79 % selon la stratégie vaccinale actuelle. Si les performances du test étaient confirmées à plus large échelle, en France, sur 800 000 naissances annuelles le test rapide permettrait d’éviter 300 000 vaccinations. [ABSTRACT FROM AUTHOR]