54 research outputs found
Cellular death of two non-saccharomyces wine-related yeasts during mixed fermentations with saccharomyces cerevisiae
The early death of two non-Saccharomyces wine strains (H. guilliermondii and H. uvarum) during mixed fermentations with S. cerevisiae was
studied under enological growth conditions. Several microvinifications were performed in synthetic grape juice, either with single non-
Saccharomyces or with mixed S. cerevisiae/non-Saccharomyces inocula. In all mixed cultures, non-Saccharomyces yeasts grew together with
S. cerevisiae during the first 1â3 days (depending on the initial inoculum concentration) and then, suddenly, non-Saccharomyces cells began to die
off, regardless of the ethanol concentrations present. Conversely, in both non-Saccharomyces single cultures the number of viable cells remained
high (ranging 107â108 CFU mlâ 1) even when cultures reached significant ethanol concentrations (up to 60â70 g lâ 1). Thus, at least for these yeast
strains, it seems that ethanol is not the main death-inducing factor. Furthermore, mixed cultures performed with different S. cerevisiae/
H. guilliermondii inoculum ratios (3 :1; 1:2; 1: 10; 1 : 100) revealed that H. guilliermondii death increases for higher inoculum ratios. In order to
investigate if the nature of the yeastâyeast interaction was related or not with a cellâcell contact-mediated mechanism, cell-free supernatants
obtained from 3 and 6 day-old mixed cultures were inoculated with H. guilliermondii pure cultures. Under these conditions, cells still died and
much higher death rates were found for the 6 days than for the 3 day-old supernatants. This strongly indicates that one or more toxic compounds
produced by S. cerevisiae triggers the early death of the H. guilliermondii cells in mixed cultures with S. cerevisiae. Finally, although it has not
been yet possible to identify the nature of the toxic compounds involved in this phenomenon we must emphasise that the S. cerevisiae strain used
in the present work is killer sensitive with respect to the classical killer toxins, K1, K2 and K28, whereas the H. guilliermondii and H. uvarum
strains are killer neutral
Heavy sulphur compounds, higher alcohols and esters production profile of Hanseniaspora uvarum and Hanseniaspora guilliermondii grown as pure and mixed cultures in grape must
Hanseniaspora guilliermondii and Hanseniaspora uvarum were tested in grape must fermentations as pure and mixed starter cultures with Saccharomyces cerevisiae. In pure cultures, the specific growth rates found were 0.29 hâ»Âč for H. uvarum, 0.23 hâ»Âč for H. guilliermondii and 0.18 hâ»Âč for S. cerevisiae. No significant differences
were observed between these values and those obtained in mixed cultures. Results presented in this work show that growth of apiculate yeasts during the first days of fermentation enhances the production of
desirable compounds, such as esters, and may not have a negative influence on the production of higher alcohols and undesirable heavy sulphur compounds. Growth of apiculate yeasts reduced the total content of higher alcohols in wines, when compared to those produced by a pure culture of S. cerevisiae. Furthermore, the highest levels of 2-phenylethyl acetate were obtained when H. guilliermondii was inoculated in grape musts, whereas H. uvarum increased the isoamyl acetate content of wines. Apiculate yeasts produced high amounts
of ethyl acetate; however, the level of this compound decreased in mixed cultures of apiculate yeasts and S. cerevisiae. When S. cerevisiae was used as a starter culture, wines showed higher concentrations of glycerol, 2-phenylethanol and ethyl hexanoate. In mixed cultures of apiculate yeasts and S. cerevisiae, wines presented
amounts of methionol, acetic acid-3-(methylthio)propyl ester, 4-(methylthio)-1-butanol, 2-mercaptoethanol
and cis-2-methyltetrahydro-thiophen-3-ol similar to those produced by a pure culture of S. cerevisiae. An increase in the amounts of 3-(ethylthio)-1-propanol, trans-2-methyltetrahydro-thiophen-3-ol and 3-
mercapto-1-propanol was obtained in wines produced from mixed cultures with H. guilliermondii
Vitrification of Iberian wolf (Canis lupus signatus) sperm: A possible alternative to conventional cryopreservation
9 PĂĄg.
Departamento de ReproducciĂłn animal. (INIA)Sperm vitrification is a simple, inexpensive method that allows the cryopreservation of sperm in the field and for endangered species is a useful alternative to conventional freezing. The study, therefore, is focused on the suitability of vitrification for cryopreserving Iberian wolf sperm and utilizing plasma testosterone concentration as a marker for procedure efficacy. Sperm and blood samples were collected from 17 wolves. There were 14 samples suitable for cryopreservation (12 ejaculated and two epididymal). Immediately after collection, these samples were proportioned into two aliquots for conventional freezing using a Tris-citric acid-glucose based extender (TCG) or vitrification utilizing an animal protein free extender (HTFÂź). Vitrification occurred by directly plunging a sperm suspension into liquid nitrogen. Sperm were assessed for motility, membrane integrity, acrosomal status and DNA integrity before and after cryopreservation. With both techniques, there were similar post-thaw/warming results (PÂ >Â 0.05) with respect to progressive motility, kinetic variables VCL, VSL, VAP and BCF, DNA fragmentation, sperm membrane functionality and morphological abnormalities. Total motile sperm, progression ratios LIN, STR, and WOB, the ALH, sperm viability and sperm with intact membrane and acrosome were greater (PÂ <Â 0.05) in the conventional frozen-thawed sperm than vitrified-warmed sperm. Plasma testosterone concentrations varied from 0.0Â ng/mL to 7.7Â ng/mL. For epididymal sperm, sperm motility and viability following thawing were greater in vitrified-warmed samples than conventionally-frozen samples; however, small sample numbers precluded statistical analysis. When considered together, these results indicate vitrification may be a possible alternative for wolf sperm cryopreservation.This research was funded by MCINN/AEI/FEDER grant AGL2017-85753-R and by the FundaciĂłn Parques Reunidos INIA agreement CC19-096.Peer reviewe
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative
Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research
Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study
Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk
Starter Culture Selection for Making Chinese Sesame-Flavored Liquor Based on Microbial Metabolic Activity in Mixed-Culture Fermentation
Dominance of wine Saccharomyces cerevisiae strains over S. kudriavzevii in industrial fermentation competitions is related to an acceleration of nutrient uptake and utilization
Grape must is a sugarârich habitat for a complex microbiota which is replaced by Saccharomyces cerevisiae strains during the first fermentation stages. Interest on yeast competitive interactions has recently been propelled due to the use of alternative yeasts in the wine industry to respond to new market demands. The main issue resides in the persistence of these yeasts due to the specific competitive activity of S. cerevisiae. To gather deeper knowledge of the molecular mechanisms involved, we performed a comparative transcriptomic analysis during fermentation carried out by a wine S. cerevisiae strain and a strain representative of the cryophilic S. kudriavzevii, which exhibits high genetic and physiological similarities to S. cerevisiae, but also differences of biotechnological interest. In this study, we report that transcriptomic response to the presence of a competitor is stronger in S. cerevisiae than in S. kudriavzevii. Our results demonstrate that a wine S. cerevisiae industrial strain accelerates nutrient uptake and utilization to outcompete the coâinoculated yeast, and that this process requires cellâtoâcell contact to occur. Finally, we propose that this competitive phenotype evolved recently, during the adaptation of S. cerevisiae to manâmanipulated fermentative environments, since a nonâwine S. cerevisiae strain, isolated from a North American oak, showed a remarkable low response to competition.JAR was supported by a FPI grant from the Ministerio de Economia y Competitividad, Spain (ref. BESâ2013â066434). This work was funded by grants AGL2015â67504âC3â1âR and AGL2015â67504âC3â3âR from the Spanish Government and European Regional Development Fund (ERDF) to AQ and EB respectively. RPT is supported by the aforementioned grant associated to AQ.Peer reviewe
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