The prognostic significance of tumour-stroma ratio in endometrial carcinoma.

Background: High tumour stromal content has been found to predict adverse clinical outcome in a range of epithelial tumours. The aim of this study was to assess the prognostic significance of tumour-stroma ratio (TSR) in endometrial adenocarcinomas and investigate its relationship with other clinicopathological parameters. Methods: Clinicopathological and 5-year follow-up data were obtained for a retrospective series of endometrial adenocarcinoma patients (n = 400). TSR was measured using a morphometric approach (point counting) on digitised histologic hysterectomy specimens. Inter-observer agreement was determined using Cohen’s Kappa statistic. TSR cut-offs were optimised using log-rank functions and prognostic significance of TSR on overall survival (OS) and disease-free survival (DFS) were determined using Cox Proportional Hazards regression analysis and Kaplan-Meier curves generated. Associations of TSR with other clinicopathological parameters were determined using non-parametric tests followed by Holm-Bonferroni correction for multiple comparisons. Results: TSR as a continuous variable associated with worse OS (P = 0.034) in univariable Cox-regression analysis. Using the optimal cut-off TSR value of 1.3, TSR-high (i.e. low stroma) was associated with worse OS (HR = 2.51; 95 % CI = 1.22–5.12; P = 0.021) and DFS (HR = 2.19; 95 % CI = 1.15–4.17; P = 0.017) in univariable analysis. However, TSR did not have independent prognostic significance in multivariable analysis, when adjusted for known prognostic variables. A highly significant association was found between TSR and tumour grade (P < 0.001) and lymphovascular space invasion (P < 0.001), both of which had independent prognostic significance in this study population. Conclusions: Low tumour stromal content associates with both poor outcome and with other adverse prognostic indicators in endometrial cancer, although it is not independently prognostic. These findings contrast with studies on many - although not all - cancers and suggest that the biology of tumour-stroma interactions may differ amongst cancer types

Molecular analysis of the genes involved in aroma synthesis in the species S. cerevisiae, S. kudriavzevii and S. bayanus var. uvarum in winemaking conditions

The Saccharomyces genus is the main yeast involved in wine fermentations to play a crucial role in the production and release of aromatic compounds. Despite the several studies done into the genome-wide expression analysis using DNA microarray technology in wine S. cerevisiae strains, this is the first to investigate other species of the Saccharomyces genus. This research work investigates the expression of the genes involved in flavor compound production in three different Saccharomyces species (S. cerevisiae, S. bayanus var. uvarum and S. kudriavzevii ) under low (12°C) and moderate fermentation temperatures (28°C). The global genes analysis showed that 30% of genes appeared to be differently expressed in the three cryophilic strains if compared to the reference strain (mesophilic S. cerevisiae), suggesting a very close cold adaptation response. Remarkable differences in the gene expression level were observed when comparing the three species, S. cerevisiae, S. bayanus var. uvarum and S. kudriavzevii, which will result in different aroma profiles. Knowledge of these differences in the transcriptome can be a tool to help modulate aroma to create wines with the desired aromatic traits. © 2014 Gamero et al.AGL2009-12673-CO2-01, AGL2012-39937-C02-01 and from the Spanish Government and PROMETEO grant (Project PROMETEO/2009/019) from the Generalitat Valenciana to A. Querol. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer Reviewe

Effect of pure and mixed cultures of the main wine yeast species on grape must fermentations

10 pages, 2 figures, 3 tables.-- Printed version published June 2010.-- The original publication is available at www.springerlink.comMixed inoculation of non-Saccharomyces yeasts and S. cerevisiae is of interest for the wine industry for technological and sensory reasons. We have analysed how mixed inocula of the main non-Saccharomyces yeasts and S. cerevisiae affect fermentation performance, nitrogen consumption and volatile compound production in a natural Macabeo grape must. Sterile must was fermented in triplicates and under the following six conditions: three pure cultures of S. cerevisiae, Hanseniaspora uvarum and Candida zemplinina and the mixtures of H. uvarum:S. cerevisiae (90:10), C. zemplinina:S. cerevisiae (90:10) and H. uvarum:C. zemplinina:S. cerevisiae (45:45:10). The presence of non-Saccharomyces yeasts slowed down the fermentations and produced higher levels of glycerol and acetic acid. Only the pure H. uvarum fermentations were unable to finish. Mixed fermentations consumed more of the available amino acids and were more complex and thus better able to synthesise volatile compounds. However, the amount of acetic acid was well above the admissible levels and compromises the immediate application of mixed cultures.The present work has been financed by the projects AGL2007-66417-C02-02/ALI and AGL2007-65498-C02-02/ALI of the Spanish Ministry of Education and Science.Peer reviewe

Genomic and transcriptomic analysis of aroma synthesis in two hybrids between Saccharomyces cerevisiae and S. kudriavzevii in winemaking conditions

[Background] Aroma is one of the most important attributes defining wine quality in which yeasts play a crucial role, synthesizing aromatic compounds or releasing odourless conjugates. A present-day trend in winemaking consists of lowering fermentation temperature to achieve higher aroma production and retention. S. cerevisiae × S. kudriavzevii hybrids seem to have inherited beneficial traits from their parental species, like fermenting efficiently at low temperature or producing higher amounts of certain aromatic compounds. In this study, allelic composition and gene expression of the genes related to aroma synthesis in two genetically and phenotypically different S. cerevisiae × S. kudriavzevii hybrids, Lalvin W27 and VIN7, were compared and related to aroma production in microvinifications at 12 and 28 °C. In addition, the contribution of the allele coming from each parental to the overall expression was explored by RT-PCR.[Results] The results indicated large differences in allele composition, gene expression and the contribution of each parental to the overall expression at the fermentation temperatures tested. Results obtained by RT-PCR showed that in ARO1 and ATF2 genes the S. kudriavzevii allele was more expressed than that of S. cerevisiae particularly at 12 °C.[Conclusions] This study revealed high differences regarding allele composition and gene expression in two S. cerevisiae × S. kudriavzevii hybrids, which may have led to different aroma profiles in winemaking conditions. The contribution of the alleles coming from each parental to the overall expression has proved to differently influence aroma synthesis. Besides, the quantitative contribution to the overall gene expression of the alleles coming from one parental strain or the other was clearly determined by the fermentation temperature for some genes.This work has been supported by the projects AGL2012-39937-C02-01 from the Spanish Government and FEDER to A. Querol. AG acknowledge to her PhD contract from I3P program.Peer reviewe

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

A novel approach to assess body composition in children with obesity from density of the fat-free mass

Background & aims: Assessment of Fat Mass (FM) and fat free mass (FFM) using Air-displacement plethysmography (ADP) technique assumes constant density of FFM (DFFM) by age and sex. It has been recently shown that DFFM further varies according to body mass index (BMI), meaning that ADP body composition assessments of children with obesity could be biased if DFFM is assumed to be constant. The aim of this study was to validate the use of the calculations of DFFM (rather than constant density of the FFM) to improve accuracy of body composition assessment in children with obesity. / Methods: cross-sectional validation study in 66 children with obesity (aged 8–14 years) where ADP assessments of body composition assuming constant density (FFMBODPOD and FMBODPOD) were compared to those where DFFM was adjusted in relation to BMI (FFMadjusted and FMadjusted), and both compared to the gold standard reference, the 4-component model (FFM4C and FM4C). / Results: FFMBODPOD was overestimated by 1.50 kg (95%CI -0.68 kg, 3.63 kg) while FFMadjusted was 0.71 kg (−1.08 kg, 2.51 kg) (percentage differences compared to FFM4C were 4.9% (±2.9%) and 2.8% (±2.1%), respectively (p < 0.001)). Consistently, FM was underestimated by both methods, representing a mean difference between methods of 4.0% (±2.9%) and 6.8% (±3.8%), respectively, when compared to the reference method. The agreement and reliability of body composition assessments were improved when adjusted using calculations (adjusted models) rather than assuming constant DFFM. / Conclusions: The use of constant values for fat-free mass properties may increase bias when assessing body composition (FM and FFM) in children with obesity by two-component techniques such as ADP. Using adjusted corrections as proposed in the present work may reduce the bias by half