Summary
The fermentation of grape must using non‐Saccharomyces yeasts with particular metabolic and biochemical properties is of growing interest. In the present work, red grape must was fermented ...using four strains of Schizosaccharomyces pombe (935, 936, 938 and 2139), Saccharomyces cerevisiae 7VA and Saccharomyces uvarum S6U, and comparisons were made over the fermentation period in terms of must sugar (glucose + fructose), malic acid, acetic acid, ammonia, primary amino nitrogen, lactic acid, urea (a possible fermentation activator or precursor of other metabolites) and pyruvic acid (a molecule affecting vitisin formation and therefore colour stability) concentration. The colour intensity of the fermenting musts was also recorded. The Schizosaccharomyces strains consumed less primary amino nitrogen and produced less urea and more pyruvic acid than other Saccharomyces species. Further, three of the four Schizosaccharomyces strains completed the breakdown of malic acid by day 4 of fermentation. The main negative effect of the use of Schizosaccharomyces was strong acetic acid production. The Schizosaccharomyces strains that produced most pyruvic acid (938 and 936) were associated with better ‘wine’ colour than the remaining yeasts. The studied Schizosaccharomyces could therefore be of oenological interest.
We set out to identify the prognostic factors in adult patients with Candida spp. bloodstream infection, assessing the impact on in-hospital mortality of catheter removal and adequacy of antifungal ...therapy.
Patients with positive blood culture for Candida spp. and a central venous catheter in place at the time of candidaemia were included. Data collected included demographics, underlying diseases, severity of illness, clinical presentation, catheter withdrawal and adequacy of empirical therapy.
We included 188 patients (mortality 36.7%). The mortality rate was 34.9% (23/66) in patients with early adequate antifungal treatment and 18.9% (7/37) in patients with early adequate antifungal therapy and catheter withdrawal in the first 48 h. The APACHE (Acute Physiology and Chronic Health Evaluation) II score on the day of candidaemia adjusted hazard ratio (aHR) 1.12; 95% CI 1.06-1.17; P < 0.001 was associated with death whereas early adequate therapy (aHR 0.4; 95% CI 0.23-0.83; P = 0.012) and catheter withdrawal (aHR 0.34; 95% CI 0.16-0.70; P = 0.03) were protective factors. In primary candidaemia, mortality was 28% (14/50) in patients with adequate therapy and decreased to 17.7% (6/34) in patients with both interventions in the first 48 h. Catheter removal was a protective factor and adequacy of antifungal therapy in the first 48 h showed a strong tendency to protection against death (aHR 0.46; 95% CI 0.19-1.08; P = 0.07). In secondary non-catheter-related candidaemia, only early adequate therapy was a protective factor for mortality.
Delay in catheter withdrawal and in administration of adequate antifungal therapy was associated with increased mortality in candidaemic patients. Catheter management did not influence the prognosis of secondary non-catheter-related candidaemia.
To model the standard broth microdilution method, based on a modified Gompertz function, to obtain accurate vancomycin MIC values for methicillin-resistant Staphylococcus aureus (MRSA). The effect of ...these MIC values on the vancomycin therapeutic target of AUC(0-24)/MIC ≥ 400 was evaluated.
Three clinical isolates of MRSA with different vancomycin MIC values were used in this model. The optical densities (OD) of each MIC determination were modelled by a non-linear regression method using an F-test. The OD data were adjusted to the Gompertz equation to obtain the MIC values. The mean vancomycin AUC(0-24) obtained with a 30 mg/kg/day dosing schedule was calculated using a Monte Carlo simulation over 5000 subjects, using the pharmacokinetic data obtained in vancomycin-treated patients in our hospital.
Although the MIC values obtained with this model were lower than those of the diffusion method (Etest) in all three cases, this did not affect the AUC(0-24)/MIC ratio for the strains with MICs of 1 mg/L by Etest. However, in those strains with MIC values >1 mg/L, the confidence intervals obtained for this ratio included values <400.
The inherent variability of the broth microdilution method could explain the differences in the clinical outcome in MRSA-infected patients treated with vancomycin, mainly in those due to strains with MIC values of 1.5-2 mg/L by Etest, because the corresponding MIC values would range from 0.84 to 1.52 mg/L by the microdilution method, which could affect the therapeutic target.
•This work verifies the adsorption/diffusion of wood phenolics on/from yeast cell-walls.•The technique could lead to a quick and better integration of wood aroma.•Other woods rather than oak show ...adequate volatile and phenolic compositions.•These woods could significantly reduce wine ageing periods irrespective of the method used.•Some marker compounds could lead to the determination of wood botanical origin.
This study develops a new method to produce more complex wines by means of an indirect diffusion of wood aromas from yeast cell-walls. An exogenous lyophilized biomass was macerated with an ethanol wood extract solution and subsequently dried. Different times were used for the adsorption of polyphenols and volatile compounds to the yeast cell-walls.
The analysis of polyphenols and volatile compounds (by HPLC/DAD and GC–MS, respectively) demonstrate that the adsorption/diffusion of these compounds from the wood to the yeast takes place. Red wines were also aged with Saccharomyces cerevisiae lees that had been impregnated with wood aromas and subsequently dried. Four different types of wood were used: chestnut, cherry, acacia and oak. Large differences were observed between the woods studied with regards to their volatile and polyphenolic profiles.
Sensory evaluations confirmed large differences even with short-term contact between the wines and the lees, showing that the method could be of interest for red wine making. In addition, the results demonstrate the potential of using woods other than oak in cooperage.
The global crisis of bacterial resistance urges the scientific community to implement intervention programs in healthcare facilities to promote an appropriate use of antibiotics. However, the ...clinical benefits or the impact on resistance of these interventions has not been definitively proved.
We designed a quasi-experimental intervention study with an interrupted time-series analysis. A multidisciplinary team conducted a multifaceted educational intervention in our tertiary-care hospital over a 5-year period. The main activity of the program consisted of peer-to-peer educational interviews between counselors and prescribers from all departments to reinforce the principles of the proper use of antibiotics. We assessed antibiotic consumption, incidence density of Candida and multidrug-resistant (MDR) bacteria bloodstream infections (BSIs) and their crude death rate per 1000 occupied bed days (OBDs).
A quick and intense reduction in antibiotic consumption occurred 6 months after the implementation of the intervention (change in level, -216.8 defined daily doses per 1000 OBDs; 95% confidence interval, -347.5 to -86.1), and was sustained during subsequent years (average reduction, -19,9%). In addition, the increasing trend observed in the preintervention period for the incidence density of candidemia and MDR BSI (+0.018 cases per 1000 OBDs per quarter; 95% confidence interval, -.003 to .039) reverted toward a decreasing trend of -0.130 per quarter (change in slope, -0.029; -.051 to -.008), and so did the mortality rate (change in slope, -0.015; -.021 to -.008).
This education-based antimicrobial stewardship program was effective in decreasing the incidence and mortality rate of hospital-acquired candidemia and MDR BSI through sustained reduction in antibiotic use.
Desde el punto de vista microbiológico la identificación y detección de Listeria monocytogenes (Lm) está bien establecida, pero no bien resuelta en algunas circunstancias. En la actualidad, los ...mayores retos en la identificación de Lm son: la identificación segura de los aislamientos de Lm con características hemolíticas atípicas y la detección de Lm en un estado fisiológicamente viable pero no cultivable (VBNC) en respuesta al estrés. Estos aspectos, no están bien establecidos o no están contemplados en la normativa UNE-EN ISO 11290.
Desde el punto de vista de la identificación segura, los mayores problemas ocurren con los aislados de Lm con débil o ausente capacidad hemolítica, los aislados con fenotipo de hemólisis atípico y en la discriminación de los aislados de Listeria innocua con características hemolíticas.
Respecto a la detección Lm con fenotipo de no cultivabilidad, los problemas radican en la puesta en evidencia de los aislados en las biopelículas que se forman en las instalaciones de procesamiento de alimentos o en las infecciones que involucran dispositivos protésicos. Otro hecho importante, es la detección en las hojas de los vegetales sometidos a procesos de conservación y en las infecciones que producen abscesos.
The time to positivity (TTP) of blood cultures in patients with bloodstream infections (BSIs) has been considered to be a possible prognostic tool for some bacterial species. However, notable ...differences have been found between sampling designs and statistical methods in published studies to date, which makes it difficult to compare results or to derive reliable conclusions. Our objective was to evaluate the clinical and microbiological implications of TTP among patients with BSI caused by the most common pathogens.
A total of 361 episodes of BSI were reported for 332 patients. The survival of the entire cohort was measured from the time of blood culture sampling. In order to compare our results with those of previous studies, TTP was divided in three different groups based on log rank (short TTP <12h; medium TTP ≥12h to ≤27h, and long TTP >27h). Cox proportional hazard models were used to calculate crude and adjusted hazard ratios (HR).
The Cox proportional hazard model revealed that TTP is an independent predictor of mortality (HR=1.00, p=0.031) in patients with BSIs. A higher mortality was found in the group of patients with the shortest TTP (<12h) (HR=2.100, p=0.047), as well as those with longest TTP (>27h) (HR=3.277, p=0.031).
It seems that TTP may provide a useful prognostic tool associated with a higher risk of mortality, not only in patients with shorter TTP, but also in those with longer TTP.
Recombination is an evolutionary strategy to quickly acquire new viral properties inherited from the parental lineages. The systematic survey of the SARS-CoV-2 genome sequences of the Andalusian ...genomic surveillance strategy has allowed the detection of an unexpectedly high number of co-infections, which constitute the ideal scenario for the emergence of new recombinants. Whole genome sequence of SARS-CoV-2 has been carried out as part of the genomic surveillance programme. Sample sources included the main hospitals in the Andalusia region. In addition to the increase of co-infections and known recombinants, three novel SARS-CoV-2 delta-omicron and omicron-omicron recombinant variants with two break points have been detected. Our observations document an epidemiological scenario in which co-infection and recombination are detected more frequently. Finally, we describe a family case in which co-infection is followed by the detection of a recombinant made from the two co-infecting variants. This increased number of recombinants raises the risk of emergence of recombinant variants with increased transmissibility and pathogenicity.
The aim of this study was to describe the safety profile and pharmacokinetic/pharmacodynamic parameters in end‐stage renal disease patients who received gentamicin as empirical treatment in ...catheter‐related bacteremia when they showed infection signs, regardless of the timing of the next HD. Patients received gentamicin 3 mg/kg before blood culture extraction when they showed infection signs and regardless of the timing of next hemodialysis session. Serum concentrations were collected after the gentamicin administration (peak level) and before the next HD (trough level). Toxicities and adverse drug events were registered. The main pharmacokinetic/pharmacodynamic goal for Gram‐negative infections was peak:minimum inhibitory concentration (MIC) ≥10. Sixteen patients were included. Nephrotoxicity was not assessed in this population, and no ototoxicity was found. According to microbial isolation and gentamicin susceptibility, the value of peak:MIC was 5.4 ± 2.0. The administration of gentamicin in these conditions was safe. Estimated pharmacokinetic values were consistent with previous studies and appropriate according to peak:MIC goal for Gram‐negative organisms with MIC ≤1 mg/L.
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