Isolation and characterization of cryotolerant Saccharomyces strains

Cryotolerant Saccharomyces strains were isolated from grape must (Pinot noir) using the enrichment method (CASTELLARI et al. 1992). Eleven cryotolerant strains were collected which all belonged to the S. uvarum species (Melibiose test and karyotype). Fermentations were carried out at 10 and 25 °C, the level of fermentation products was compared with those produced by mesophilic yeasts. Regardless of temperature, cryotolerant yeasts (SY055 and 12233) produced twice as many isobutyl and isoamyl alcohols as mesophilic yeast (FB) and 2-phenethyl alcohol was produced by cryotolerant yeasts at levels 4 times as high as by mesophilic yeasts. The potential of these yeasts for oenological application is discussed

The aroma glycosides composition of Burgundy Pinot noir must

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Isolation, characterisation, and selection of wine yeast strains in Etyek-Buda wine district, Hungary

Initiated by the Association “Wine Route of Etyek Wine District”, the objectives of this study were to isolate and identify autochthonous yeast strains from local wines and to determine their oenologically important properties. The first aim of this work was to characterize the taxonomic and phenotypic diversity of the representative Saccharomyces yeast strains that dominate the spontaneous fermentations in this wine district. The results obtained by molecular ribotyping (ARDRA) revealed a strong dominance of S. cerevisiae, but S. bayanus var. uvarum was also present sporadically. Some of the natural isolates exhibited high volatile acid production or poor fermentation capacity, which imply a quality risk in spontaneous fermentations. Most of the isolates, however, displayed good oenological features during lab scale fermentations. As the second aim of this work, the most promising, selected strains were further tested for oenological properties in microvinification scale and, finally, in large scale fermentations. The analytical and sensory analysis proved that selected strains, including S. bayanus var. uvarum, can be used as local starter cultures, which may contribute to the typicality of the local wines in comparison with commercial starters

The aroma glycosides composition of burgundy Pinot noir must

International audienc

The aroma glycosides composition of burgundy Pinot noir must

International audienc

Breastfeeding assessment score : systematic review and meta-analysis

BACKGROUND: Previous studies have revealed conflicting results for the Breastfeeding Assessment Score (BAS) in predicting early breastfeeding cessation. Our objective was to externally validate the BAS and provide summary accuracy estimates for this clinical prediction model. METHODS: We used the original data from a prospective cohort study. Additional studies were identified by searching electronic databases (Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, and Cochrane) from 2002 to 2013 and contacting research groups that had derived or validated the BAS. Prospective cohort studies were eligible if the BAS was computed at baseline and mothers were followed up for breastfeeding cessation. Two physicians extracted relevant information and independently assessed the methodological quality for the included studies. RESULTS: In the external validation cohort, 22 of 424 mothers (5.2%) discontinued breastfeeding within 14 days of infant age. The BAS predicted early breastfeeding cessation with an area under the curve of 0.70 (95% confidence interval [CI]: 0.65 to 0.74) and inadequate calibration. When restricting the meta-analysis to 3169 mother-infant pairs enrolled in 4 higher-quality studies, a BAS value <8 predicted early cessation with 0.80 sensitivity (95% CI: 0.69 to 0.91) and 0.51 specificity (95% CI: 0.32 to 0.70) summary estimates. CONCLUSIONS: Substantial between-study heterogeneity limited the interpretation of summary accuracy estimates. The BAS predicts early breastfeeding cessation with moderate accuracy, although local recalibration is advised before implementation. Further study is warranted to determine whether the BAS can help pediatricians in identifying mother-infant pairs that may benefit from more extensive breastfeeding assessment and support

Reperfusion des infarctus aigus avec sus-décalage du segment ST dans le RENAU/RESURCOR : des recommandations à la pratique [Reperfusion in ST elevation myocardial infarction. From the guidelines to practice]

International guidelines have recommendations for selecting the type of reperfusion (fibrinolysis or angioplasty) in the setting of ST-segment elevation myocardial infarction (STEMI), and suggest that emergency-care networks adapt these recommendations according to the local environment. To assess the proportions of STEMI patients treated with fibrinolysis or angioplasty in accordance with regional guidelines. Observational study based on a permanent registry of patients with STEMI of &lt;12h duration in an emergency network in the French North Alps (Isère, Savoie, Haute-Savoie) from January 2009 to December 2012. The registry included 2620 patients. Reperfusion was given in 2425/2620 (93%) of patients. Reperfusion type was in accordance with recommendations in 1567/2620 (60%) patients. Guideline-recommended fibrinolysis and angioplasty were performed in 47% (656/1385) and 79% (911/1149) respectively, of patients. In multivariable analysis, variables independently associated with guideline-recommended reperfusion were: an age &lt; 65 years (OR 1.60; 95%CI 1.33-1.90), being managed in Haute-Savoie versus Isère or Savoie (OR 1.38; 95%CI 1.12-1.71), an arterial tension &lt; 100mmHg (OR 1.73; 95%CI 1.27-2.35), a cardiogenic shock (OR 0.50; 95%CI 0.30-0.84), a pacemaker or left bundle branch block (OR 0.49; 95%CI 0.28-0.88), and an initial management outside the network (followed by treatment in an interventional centre in the network) (OR 0.62; 95%CI 0.40-0.94). Patients initially treated by mobile intensive care units were more often reperfused in accordance with recommendations when admitted &lt; 3 (versus ≥ 3) h following symptom onset (adjusted OR 2.05; 95% CI 1.61-2.59), while those initially treated by in-hospital emergency units were less often reperfused in accordance with recommendation when treated &lt; 3h following symptom onset (adjusted OR 0.67; 95% CI 0.46-0.97). In-hospital major adverse cardiac events (9.1% vs. 8.5%) and in-hospital mortality (6.4% vs. 5.1%) were not significantly different between patients reperfused in accordance with (versus not) recommendations. Forty percent of patients with STEMI were not reperfused with fibrinolysis or angioplasty in accordance with regional guidelines. Characterization of this population should allow us to improve guideline adherence

Evolutionary engineering of a wine yeast strain revealed a key role of inositol and mannoprotein metabolism during low-temperature fermentation

[Background] Wine produced at low temperature is often considered to improve sensory qualities. However, there are certain drawbacks to low temperature fermentations: e.g. low growth rate, long lag phase, and sluggish or stuck fermentations. Selection and development of new Saccharomyces cerevisiae strains well adapted at low temperature is interesting for future biotechnological applications. This study aimed to select and develop wine yeast strains that well adapt to ferment at low temperature through evolutionary engineering, and to decipher the process underlying the obtained phenotypes.[Results] We used a pool of 27 commercial yeast strains and set up batch serial dilution experiments to mimic wine fermentation conditions at 12 °C. Evolutionary engineering was accomplished by using the natural yeast mutation rate and mutagenesis procedures. One strain (P5) outcompeted the others under both experimental conditions and was able to impose after 200 generations. The evolved strains showed improved growth and low-temperature fermentation performance compared to the ancestral strain. This improvement was acquired only under inositol limitation. The transcriptomic comparison between the evolved and parental strains showed the greatest up-regulation in four mannoprotein coding genes, which belong to the DAN/TIR family (DAN1, TIR1, TIR4 and TIR3). Genome sequencing of the evolved strain revealed the presence of a SNP in the GAA1 gene and the construction of a site-directed mutant (GAA1Thr108) in a derivative haploid of the ancestral strain resulted in improved fermentation performance. GAA1 encodes a GPI transamidase complex subunit that adds GPI, which is required for inositol synthesis, to newly synthesized proteins, including mannoproteins.[Conclusions] In this study we demonstrate the importance of inositol and mannoproteins in yeast adaptation at low temperature and the central role of the GAA1 gene by linking both metabolisms.This work has been financially supported by grants AGL2013-47300-C3-3-R and PROMETEOII/2014/042 from the Spanish government and the Generalitat Valenciana, respectively, awarded to JMG. MLM and EGR also want to thank the Spanish government for her FPI grants. Analysis of yeast genomic sequences was made possible through the NIH P41 GM103533 grant funding the Yeast Resource Center. MJD is a Rita Allen Scholar and Fellow in the Genetic Networks program at the Canadian Institute for Advanced Research. MS was supported by NSF fellowship DGE-1256082