QTL mapping reveals novel genes and mechanisms underlying variations in H2S production during alcoholic fermentation in Saccharomyces cerevisiae.

Saccharomyces cerevisiae requirement for reduced sulfur to synthesize methionine and cysteine during alcoholic fermentation, is mainly fulfilled through the sulfur assimilation pathway. Saccharomyces cerevisiae reduces sulfate into sulfur dioxide (SO2) and sulfide (H2S), whose overproduction is a major issue in winemaking, due to its negative impact on wine aroma. The amount of H2S produced is highly strain-specific and also depends on SO2 concentration, often added to grape must. Applying a bulk segregant analysis to a 96-strain-progeny derived from two strains with different abilities to produce H2S, and comparing allelic frequencies along the genome of pools of segregants producing contrasting H2S quantities, we identified two causative regions involved in H2S production in the presence of SO2. A functional genetic analysis allowed the identification of variants in four genes able to impact H2S formation, viz; ZWF1, ZRT2, SNR2, and YLR125W, and involved in functions and pathways not associated with sulfur metabolism until now. These data point out that, in wine fermentation conditions, redox status, and zinc homeostasis are linked to H2S formation while providing new insights into the regulation of H2S production, and a new vision of the interplay between the sulfur assimilation pathway and cell metabolism.

Occlusal Outcomes in Non-Robin Sequence Patients with Isolated Cleft Palate.

OBJECTIVES: 1. To assess the skeletal class occlusion and lateral cephalometry in children with isolated cleft palates (non-Robin sequence) and 2. to identify associations between these findings and pre-palatoplasty cleft palate measurements. STUDY DESIGN: Retrospective cohort study. SETTING: North American Institutional Tertiary Paediatric Center. PATIENTS: Our cleft database was reviewed, and patients were included if they had an isolated cleft palate without a Robin Sequence diagnosis, had a Furlow palatoplasty and had available per operative cleft palate measurements and available lateral cephalogram between 6 and 8 years old. Thirty-two patients matched to inclusion criteria. INTERVENTION: Furlow's Palatoplasty. MAIN OUTCOME AND MEASURES: Cleft size at palatoplasty, cephalometric measurements and skeletal occlusal classes were analysed. ANOVA was used to test the association between cephalometric measurements and occlusal classes. Results are presented as means with a 95% confidence interval. The association between cleft measurements and cephalometric parameters was tested with Spearman Correlation (rs). RESULTS: The skeletal occlusal outcome at 7 years old for this series of patients was: Class I: 19%; Class II: 59% and Class III: 22%. No single cleft measurement at palatoplasty was predictive of the skeletal occlusal outcome. A larger hard palate cleft was associated with a shorter antero-posterior maxilla. CONCLUSIONS: The skeletal occlusal class outcomes were similar to those found in a previous study in the literature. The occlusal prognosis appears to be better than in patients with Robin Sequence or with an associated cleft lip. No preoperative measurement was found to be associated with the occlusal outcome.

Beyond Conceptual Analysis: Social Objectivity and Conceptual Engineering to Define Disease.

In this article, I side with those who argue that the debate about the definition of "disease" should be reoriented from the question "what is disease" to the question of what it should be. However, I ground my argument on the rejection of the naturalist approach to define disease and the adoption of a normativist approach, according to which the concept of disease is normative and value-laden. Based on this normativist approach, I defend two main theses: (1) that conceptual analysis is not the right method to define disease and that conceptual engineering should be the preferred method and (2) that the method of conceptual engineering should be implemented following the principles of Alexandrova's account of social objectivity in the context of the definition of disease.

Treatment of chronic lateral epicondylosis: a randomized trial comparing the efficacy of ultrasound-guided tendon dry needling and open-release surgery.

OBJECTIVE: Evaluate the efficacy of ultrasound-guided dry needling and open-release surgery in reducing pain and improving function in workers with lateral epicondylosis refractory to at least 6 months of nonsurgical management. METHODS: We randomly assigned participants in a 1:1 ratio to receive dry needling or surgery. The primary outcome was the Patient Rated Tennis Elbow Evaluation (PRTEE) score at 6 months. Secondary outcome measures examined the impact of these techniques on professional activity, grip strength, and Global Rating of Change and Satisfaction scales. Statistical analyses included mixed-effects models and Fisher's exact tests. RESULTS: From October 2016 through June 2019, we enrolled 64 participants. Two participants were excluded, and data from 62 participants (48 ± 8 years, 33 men) with a mean duration of symptoms of 23 ± 21 months were analyzed. Baseline characteristics were similar in both groups. In the intention-to-treat analysis, no treatment-by-time interaction was observed (F(4,201) = 0.72; p = .58). The least-squares mean difference from baseline in PRTEE scores at 6 months was 33.4 (CI 25.2 - 41.5) in the surgery group and 26.9 (CI 19.4 - 34.4) in the dry needling group (p = .25). The proportion of successful treatment was 83% (CI 63 - 95%) and 81% (CI 63 - 93%) in the surgery and dry needling groups, respectively (p = 1.00). Changes in secondary outcomes were in the same direction as those of the primary outcome. No adverse event occurred. CONCLUSIONS: Ultrasound-guided dry needling resulted in comparable improvement in outcome scores on scales of pain, physical function, and global assessment of change and satisfaction than open-release surgery. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02710682 KEY POINTS: • In patients with chronic lateral epicondylosis, ultrasound-guided tendon dry needling provides comparable therapeutic efficacy to open-release surgery. • Ultrasound-guided tendon dry needling allows for an earlier return to work and may be less costly than open-release surgery. • Care management guidelines should recommend treatment by ultrasound-guided tendon dry needling before open-release surgery.

Comparison of Three Nursing Workload Assessment Tools in the Neonatal Intensive Care Unit and Their Association with Outcomes of Very Preterm Infants.

OBJECTIVE: Nursing workload assessment tools are widely used to determine nurse staffing requirements in the neonatal intensive care unit (NICU). We aimed to compare three existing workload assessment tools and assess their association with mortality or morbidity among very preterm infants. STUDY DESIGN: Single-center retrospective cohort study of infants born <33 weeks and admitted to a 52-bed tertiary NICU in 2017 to 2018. Required nurse staffing was estimated for each shift using the Winnipeg Assessment of Neonatal Nursing Needs Tool (WANNNT) used as reference tool, the Quebec Provincial NICU Nursing Ratio (QPNNR), and the Canadian NICU Resource Utilization (CNRU). Poisson regression models with robust error variance estimators were used to assess the association between nursing provision ratios (actual number of nurses/required number of nurses) during the first 7 days of admission and neonatal outcomes. RESULTS: Median number of nurses required per shift using the WANNNT was 25.0 (interquartile range [IQR]: 23.1-26.7). Correlation between WANNNT and QPNNR was high (r = 0.92, p < 0.0001), but the QPNNR underestimated the number of nurses per shift by 4.8 (IQR: 4.1-5.4). Correlation between WANNNT and CNRU was moderate (r = 0.45, p < 0.0001). The NICU nursing provision ratios during the first 7 days of admission calculated using the WANNNT (adjusted risk ratio [aRR]: 0.96, 95% confidence interval [CI]: 0.93-0.99) and QPNNR (aRR: 0.97, 95% CI: 0.95-0.99) were associated with mortality or morbidity. CONCLUSION: Lower nursing provision ratio calculated using the WANNNT and CNRU during the first 7 days of admission is associated with an increased risk of mortality/morbidity in very preterm infants. KEY POINTS: · NICUs use different nursing workload assessment tools.. · We validated three different nursing workload assessment tools used in the NICU.. · Nursing provision ratio is associated the risk of mortality/morbidity in preterm infants..

Influence of single nitrogen compounds on growth and fermentation performance of Starmerella bacillaris and Saccharomyces cerevisiae during alcoholic fermentation.

Nitrogen is among the essential nutriments that govern interactions between yeast species in the wine environment. A thorough knowledge of how these yeasts assimilate the nitrogen compounds of grape juice is an important prerequisite for a successful co- or sequential fermentation. In the present study, we investigated the efficiency of 18 nitrogen sources for sustaining the growth and fermentation of two Starm. bacillaris strains displaying metabolic properties, compared to the reference yeast S. cerevisiae The analysis of growth and fermentation parameters provided a comprehensive picture of Starm. bacillaris preferences with respect to nitrogen sources for sustained growth and fermentation. Important differences were observed in S. cerevisiae regarding rates, final population and CO2 production. In particular, Lys and His supported substantial Starm. bacillaris growth and fermentation contrary to S. cerevisiae, while only 3 nitrogen sources, Arg, NH4+ and Ser, promoted S. cerevisiae growth more efficiently than that of Starm. bacillaris strains. Furthermore, Starm. bacillaris strains displayed a higher fermentative activity than S. cerevisiae during the first phase of culture with Gly or Thr, when the former species consumed solely fructose. Finally, no correlation has been shown between the ability of nitrogen sources to support growth and their fermentation efficiency. The specificities of Starm. bacillaris regarding nitrogen sources preferences are related to its genetic background, but further investigations are needed to elucidate the molecular mechanisms involved. These data are essential elements to be taken into account in order to make the best use of the potential of the two species.IMPORTANCE Mixed fermentations combining non-Saccharomyces and S. cerevisiae strains are increasingly implemented in the wine sector as they offer promising opportunities to diversify the flavour profile of end-products. However, competition for nutrients between species can cause fermentation problems, which is a severe hindrance to the development of these approaches. With the knowledge provided in this study on the nitrogen preferences of Starm. bacillaris, winemakers will be able to set up a nitrogen nutrition scheme adapted to the requirement of each species during mixed fermentation, through must supplementation with relevant nitrogen compounds. This will prevent nitrogen depletion or competition between yeasts for nitrogen sources, and consequently potential issues during fermentation. The data of this study highlight the importance of an appropriate nitrogen resource management during co- or sequential fermentation for fully exploiting the phenotypic potential of non-Saccharomyces yeasts.

Nitrogen metabolism in three non-conventional wine yeast species: A tool to modulate wine aroma profiles.

The positive impact of certain non-Saccharomyces yeasts on the aromatic profile of wines has been well documented in literature and their industrial use in association with S. cerevisiae is now recommended. Competition between non-Saccharomyces species and Saccharomyces cerevisiae for various nutrients, especially nitrogen sources, greatly impacts the production of aroma compounds. In this study, we further explored the impact of different nitrogen nutrition strategies on the production of carbon and sulphur volatile compounds of three non-Saccharomyces strains, namely Pichia burtonii, Kluyveromyces marxianus, Zygoascus meyerae sequentially inoculated with S. cerevisiae in Sauvignon blanc and Shiraz grape musts. Nitrogen additions were implemented according the specific requirement of each species. At the end of fermentation, we observed specific metabolic signatures for each strain in response to the nature of the nitrogen source suggesting strain-specific metabolic fluxes present. Overall, these results confirmed and further explored the interconnection between nitrogen sources and aroma metabolism (including that of higher alcohols, fatty acids, esters and volatile sulphur compounds), and their variations according to species and the nature of the nitrogen source. The knowledge generated provides new insights to modulate the aroma profile of wines produced with non-Saccharomyces species.

Pilot study of anti-mitochondrial antibodies in antiphospholipid syndrome.

BACKGROUND: Mitochondria are intracellular organelles of bacterial origin capable of stimulating the immune system when released into the extracellular milieu. We previously reported the expression of anti-mitochondrial antibodies (AMA) targeting whole organelles (AwMA), mitochondrial DNA (AmtDNA) or mitochondrial RNA (AmtRNA) in patients with systemic lupus erythematosus (SLE). Antiphospholipid syndrome (APS) is an autoimmune condition that may be independent of, or associated with, other diseases, usually SLE. This study aimed to detect AMA in patients with APS and to explore the association with clinical features of APS. METHODS: AwMA-, AmtDNA- and AmtRNA-IgG and -IgM were detected in a pilot study (healthy controls n = 30 and APS patients n = 24) by direct ELISA, and their levels were associated with demographic and disease characteristics. RESULTS: AmtDNA-IgM and AmtRNA-IgG and IgM were elevated in APS compared to healthy controls (p = 0.009, p = 0.0005 and p = 0.01, respectively). AwMA-IgG were increased in patients positive for lupus anticoagulant (median ± interquartile range = 0.36 ± 0.31 vs. 0.14 ± 0.08, p = 0.008), and optical density values for AwMA-IgM were correlated with titres of IgM against cardiolipin (rs = 0.51, p = 0.01). An increment of 0.1 unit of AmtDNA-IgM levels was associated with reduced prior reporting of arterial events (odds ratio = 0.86; 95% confidence interval 0.74-1.00; p = 0.047). CONCLUSION: Our pilot study suggests that AMA are represented within the autoantibody repertoire in APS and may display different associations with the clinical manifestations of the disease. Further studies should focus on reproducing these preliminary results by following AMA levels through time in larger prospective cohorts.

CT fluoroscopy-guided transforaminal and intra-articular facet steroid injections for the treatment of cervical radiculopathy: injectate distribution patterns and association with clinical outcome.

OBJECTIVES: To investigate injectate dispersal patterns and their association with therapeutic efficacy during a transforaminal (TFSI) or an intra-articular facet steroid injection (IFSI) to treat cervical radiculopathy. METHODS: This retrospective study examined the post-intervention cervical spine CT of 56 patients randomized to receive one CT fluoroscopy-guided IFSI (29 patients; 10 (34.5%) males; mean age 45.0 years; SD 8.8 years; range 26-61 years) or TFSI (27 patients; 13 (48.2%) males; mean age 51.1 years; SD 11.2 years; range 29-72 years) (December 2010 to August 2013). The presence of contrast within the intra-articular facet, juxta-articular facet, retrodural, epidural, and foraminal and extraforaminal spaces during IFSI, and within the extraforaminal, foraminal, and epidural spaces during TFSI was assessed. Descriptive data are presented as frequencies. The association between injectate dispersal patterns and therapeutic efficacy, 4-week post-intervention, was assessed with ANCOVA models. RESULTS: During IFSI, the injectate predominantly spread to the retrodural (62%; 18/29) or juxta-articular (21%; 6/29) space. During TFSI, the injectate predominantly spread to the extraforaminal/foraminal spaces (41%; 11/27) or to the extraforaminal/foraminal/epidural spaces (33%; 9/27). Injectate presence in the juxta-articular (p = .007) or extraforaminal (p < .001) space was a predictor of therapeutic efficacy but not in the foraminal (p = .54), epidural (p = .89), or retrodural (p = .75) space. CONCLUSIONS: TFSI and IFSI led to preferential extraforaminal and retrodural injectate spread, respectively. Targeting the extraforaminal or juxta-articular facet space improved the clinical efficacy of steroid injections when treating cervical radiculopathy. KEY POINTS: • During intra-articular facet injection, the injectate spreads from the facet joint to the retrodural space and rarely reaches the epidural and/or foraminal spaces. • Epidural spread of the injectate during an anterolateral transforaminal steroid injection is the least effective for pain relief in patients with cervical radiculopathy. • Injection techniques targeting the extraforaminal or juxta-articular facet space are safer than transforaminal injections and effectively relieve pain in patients with cervical radiculopathy.

Nitrogen sources preferences of non-Saccharomyces yeasts to sustain growth and fermentation under winemaking conditions.

Wine-related non-Saccharomyces yeasts are becoming more widely used in oenological practice for their ability to confer wine a more complex satisfying aroma, but their metabolism remains unknown. Our study explored the nitrogen utilisation profile of three popular non-Saccharomyces species, Torulaspora delbrueckii, Metschnikowia pulcherrima and Metschnikowia fructicola. The nitrogen source preferences to support growth and fermentation as well as the uptake order of different nitrogen sources during wine fermentation were investigated. While T. delbrueckii and S. cerevisiae strains shared the same nitrogen source preferences, Metschnikowia sp. Displayed a lower capacity to efficiently use the preferred nitrogen compounds, but were able to assimilate a wider range of amino acids. During alcoholic fermentation, the non-Saccharomyces strains consumed different nitrogen sources in a similar order as S. cerevisiae, but not as quickly. Furthermore, when all the nitrogen sources were supplied in the same amount, their assimilation order was similarly affected for both S. cerevisiae and non-Saccharomyces strains. Under this condition, the rate of nitrogen source consumption of non-Saccharomyces strains and S. cerevisiae was comparable. Overall, this study expands our understanding about the preferences and consumption rates of individual nitrogen sources by the investigated non-Saccharomyces yeasts in a wine environment. This knowledge provides useful information for a more efficient exploitation of non-Saccharomyces strains that improves the management of the wine fermentation.

Furlow Palatoplasty, Nasopharyngeal Size, and Sleep Oximetry.

OBJECTIVES: (1) To assess the evolution of prepalatoplasty sleep oximetry (PRESO) and postpalatoplasty sleep oximetry (POSSO) in cleft patients and (2) to evaluate the impact of the size of the nasopharynx on PRESO and POSSO values. STUDY DESIGN: Retrospective cohort study. PATIENTS AND METHODS: In 81 patients with cleft palate and/or cleft lip, the following data were prospectively collected: patient demographics and prepalatoplasty cleft palate measurements. All the patients had at least 1 PRESO and POSSO. A Kaplan-Meier curve was obtained from all the sleep oximetry results. Transverse nasopharyngeal area (TNA) pre- and postvalues were compared for each group with paired t tests, while analysis of variance was used to compare TNA pre- and postscores between the groups with a Bonferroni correction for multiple comparisons. RESULTS: POSSO results were normal or showed mild desaturations in most patients in the few weeks following palatoplasty. For the cohort, no statistically significant changes were found between PRESO and POSSO values. A 2-fold variation in the area of the TNA was found before palatoplasty within identical cleft malformation cases. No statistically significant association was found between the TNA or the a/30 - b1 parameter values and the sleep study scores. CONCLUSIONS: The patients with the smaller nasopharyngeal areas presented identical PRESO and POSSO results when compared to those with larger nasopharyngeal sizes. Future studies should address the possible association between prepalatoplasty and postpalatoplasty TNAs and the occurrence of velopharyngeal deficiency later in life.

A comparison of the nitrogen metabolic networks of Kluyveromyces marxianus and Saccharomyces cerevisiae.

In grape must, nitrogen is available as a complex mixture of various compounds (ammonium and amino acids). Wine yeasts assimilate these multiple sources in order to suitably fulfil their anabolic requirements during alcoholic fermentation. Nevertheless, the order of uptake and the intracellular fate of these sources are likely to differ between strains and species. Using a two-pronged strategy of isotopic filiation and RNA sequencing, the metabolic network of nitrogen utilization and its regulation in Kluyveromyces marxianus were described, in comparison with those of Saccharomyces cerevisiae. The data highlighted differences in the assimilation of ammonium and arginine between the two species. The data also revealed that the metabolic fate of certain nitrogen sources differed, thereby resulting in the production of various amounts of key wine aroma compounds. These observations were corroborated by the gene expression analysis.

Platelet-derived extracellular vesicles convey mitochondrial DAMPs in platelet concentrates and their levels are associated with adverse reactions.

BACKGROUND: Whereas platelet transfusion is a common medical procedure, inflammation still occurs in a fraction of transfused individuals despite the absence of any apparent infectious agents. Platelets can shed membrane vesicles, called extracellular vesicles (EVs), some of which contain mitochondria (mito+EV). With its content of damage-associated molecular pattern (DAMP), the mitochondrion can stimulate the innate immune system. Mitochondrial DNA (mtDNA) is a recognized DAMP detected in the extracellular milieu in numerous inflammatory conditions and in platelet concentrates. We hypothesized that platelet-derived mitochondria encapsulated in EVs may represent a reservoir of mtDNA. STUDY DESIGN AND METHODS: Herein, we explored the implication of mito+EVs in the occurrence of mtDNA quantified in platelet concentrate supernatants that induced or did not induce transfusion adverse reactions. RESULTS: We observed that EVs were abundant in platelet concentrates, and platelet-derived mito+EVs were more abundant in platelet concentrates that induced adverse reactions. A significant correlation (rs = 0.73; p < 0.0001) between platelet-derived mito+EV levels and mtDNA concentrations was found. However, there was a nonsignificant correlation between the levels of EVs without mitochondria and mtDNA concentrations (rs = -0.11; p = 0.5112). The majority of the mtDNA was encapsulated into EVs. CONCLUSION: This study suggests that platelet-derived EVs, such as those that convey mitochondrial DAMPs, may be a useful biomarker for the prediction of potential risk of adverse transfusion reactions. Moreover, our work implies that investigations are necessary to determine whether there is a causal pathogenic role of mitochondrial DAMP encapsulated in EVs as opposed to mtDNA in solution.

Accelerometry to measure physical activity in toddlers: Determination of wear time requirements for a reliable estimate of physical activity.

Accelerometry is widely used to evaluate physical activity in toddlers however recommendations regarding wear time are needed to understand physical activity behaviours in this age group. This study aimed to determine the minimum wear time to reliably evaluate physical activity in toddlers. Children from the 3D Birth Cohort (n = 255, 49.8% boys, 2.1 ± 0.2 years) were asked to wear an accelerometer (GT3X+, ActiGraph) for 7 days. Physical activity was expressed in active time (min/day) and counts per minute (CPM). Single day intraclass correlation coefficients (ICCs) were calculated to assess the effect of varying minimal wear time on reliability estimates. The Spearman-Brown formula was used to determine wear time required to achieve reliability levels of 70%, 80% and 90%. For active time, a reliability of 72.1% was achieved with wearing the accelerometer for ≥ 4 days of ≥ 6 h, which comprised 85.9% of the sample. For CPM, ≥ 4 days of ≥ 6 h provided a reliability of 74.7% and comprised 85.9% of the children. Results differed slightly when girls and boys were analysed separately, but restricting analyses to children with a weekend day did not. In summary, a minimum of 4 days with ≥ 6 h of accelerometry data provides a reliable estimate of physical activity in 2-year toddlers.

How often do both core competencies of shared decision making occur in family medicine teaching clinics?

OBJECTIVE: To assess how often risk communication and values clarification occur in routine family medicine practice and to explore factors associated with their occurrence. DESIGN: Qualitative and quantitative cross-sectional study. SETTING: Five university-affiliated family medicine teaching clinics across Quebec. PARTICIPANTS: Seventy-one health professionals (55% physicians, 35% residents, 10% nurses or dietitians) and 238 patients (76% women; age range 16 to 82 years old). MAIN OUTCOME MEASURES: The presence or absence of risk communication and values clarification during visits in which decisions were made was determined. Factors associated with the primary outcome (both competencies together) were identified. The OPTION5 (observing patient involvement in decision making) instrument was used to validate the dichotomous outcome. RESULTS: The presence of risk communication and values clarification during visits was associated with OPTION5 scores (area under the curve of 0.80, 95% CI 0.75 to 0.86, P < .001). Both core competencies of shared decision making occurred in 150 of 238 (63%) visits (95% CI 54% to 70%). Such an occurrence was more likely when the visit included discussion about beginning something new, treatment options, or postponing a decision, as well as when health professionals preferred a collaborative decision-making style and when the visit included more decisions or was longer. Alone, risk communication occurred in 203 of 238 (85%) visits (95% CI 82% to 96%) and values clarification in 162 of 238 (68%) visits (95% CI 61% to 75%). CONCLUSION: Health professionals in family medicine are making an effort to engage patients in shared decision making in routine daily practice, especially when there is time to do so. The greatest potential for improvement might lie in values clarification; that is, discussing what matters to patients and families.

Specific Phenotypic Traits of Starmerella bacillaris Related to Nitrogen Source Consumption and Central Carbon Metabolite Production during Wine Fermentation.

Over the last few years, the potential of non-Saccharomyces yeasts to improve the sensory quality of wine has been well recognized. In particular, the use of Starmerella bacillaris in mixed fermentations with Saccharomyces cerevisiae was reported as an appropriate way to enhance glycerol formation and reduce ethanol production. However, during sequential fermentation, many factors, such as the inoculation timing, strain combination, and physical and biochemical interactions, can affect yeast growth, the fermentation process, and/or metabolite synthesis. Among them, the availability of yeast-assimilable nitrogen (YAN), due to its role in the control of growth and fermentation, has been identified as a key parameter. Consequently, a comprehensive understanding of the metabolic specificities and the nitrogen requirements would be valuable to better exploit the potential of Starm. bacillaris during wine fermentation. In this study, marked differences in the consumption of the total and individual nitrogen sources were registered between the two species, while the two Starm. bacillaris strains generally behaved uniformly. Starm. bacillaris strains are differentiated by their preferential uptake of ammonium compared with amino acids that are poorly assimilated or even produced (alanine). Otherwise, the non-Saccharomyces yeast exhibits low activity through the acetaldehyde pathway, which triggers an important redistribution of fluxes through the central carbon metabolic network. In particular, the formation of metabolites deriving from the two glycolytic intermediates glyceraldehyde-3-phosphate and pyruvate is substantially increased during fermentations by Starm. bacillaris This knowledge will be useful to better control the fermentation process in mixed fermentation with Starm. bacillaris and S. cerevisiaeIMPORTANCE Mixed fermentations using a controlled inoculation of Starmerella bacillaris and Saccharomyces cerevisiae starter cultures represent a feasible way to modulate wine composition that takes advantage of both the phenotypic specificities of the non-Saccharomyces strain and the ability of S. cerevisiae to complete wine fermentation. However, according to the composition of grape juices, the consumption by Starm. bacillaris of nutrients, in particular of nitrogen sources, during the first stages of the process may result in depletions that further limit the growth of S. cerevisiae and lead to stuck or sluggish fermentations. Consequently, understanding the preferences of non-Saccharomyces yeasts for the nitrogen sources available in grape must together with their phenotypic specificities is essential for an efficient implementation of sequential wine fermentations with Starm. bacillaris and S. cerevisiae species. The results of our study demonstrate a clear preference for ammonium compared to amino acids for the non-Saccharomyces species. This finding underlines the importance of nitrogen sources, which modulate the functional characteristics of inoculated yeast strains to better control the fermentation process and product quality.

Fermentation performances and aroma production of non-conventional wine yeasts are influenced by nitrogen preferences.

Saccharomyces cerevisiae is currently the most important yeast involved in food fermentations, particularly in oenology. However, several other yeast species occur naturally in grape must that are highly promising for diversifying and improving the aromatic profile of wines. If the nitrogen requirement of S. cerevisiae has been described in detail, those of non-Saccharomyces yeasts remain poorly studied despite their increasingly widespread use in winemaking. With a view to improving the use of non-Saccharomyces yeasts in winemaking, we explored the fermentation performances, the utilisation of nitrogen sources and the volatile compound production of 10 strains of non-conventional yeasts in pure culture. Two different conditions were tested: one mimicking the grape juice's nitrogen composition and one with all the nitrogen sources at the same level. We highlighted the diversity in terms of nitrogen preference and amount consumed among the yeast strains. Some nitrogen sources (arginine, glutamate, glycine, tryptophan and γ-aminobutyric acid) displayed the largest variations between strains throughout the fermentation. Several non-Saccharomyces strains produced important aroma compounds such as higher alcohols, acetate and ethyl esters in significantly higher quantities than S. cerevisiae.

C-reactive protein for late-onset sepsis diagnosis in very low birth weight infants.

BACKGROUND: Late-onset sepsis in very low birth weight (VLBW) infants is a diagnostic challenge. We aimed to evaluate the diagnostic utility of the C-Reactive protein (CRP) and the complete blood count (CBC) for late-onset sepsis in VLBW infants. METHODS: In a 5-year retrospective cohort of 416 VLBW infants born at less than 1500 g, there were 590 separate late-onset sepsis evaluations. CRP and CBC were drawn at time of initial blood culture (T0), at 16-24 h (T24) and 40-48 h (T48) after. The positive cut-off values for abnormal values were the following: CRP ≥10 mg/L and CBC with at least one anomaly, including white blood cell count < 5000/mm3, immature neutrophil/total neutrophil ratio > 0.10, or platelet count < 100,000/uL. Sensitivity and specificity for predicting late-onset sepsis were calculated for each laboratory test and their combinations. Receiver operating characteristics curves were obtained for each test and for the absolute change from T0 to T24 in the laboratory value of CRP, white blood cell count and immature neutrophil/total neutrophil. RESULTS: At T0, combining the CBC and the CRP had the highest sensitivity of 66% (95% confidence interval [CI], 58-73) compared to both individual tests for predicting late onset sepsis. At T24, CRP's sensitivity was 84% (95% CI, 78-89) and was statistically higher than the CBC's 59% (95% CI, 51-67). The combination of CBC at T0 and CRP at T24 offered the greatest sensitivity of 88% (95% CI, 82-92) and negative predictive value 93% (95% CI, 89-96), with fewer samples, compared to any other combination of tests. The area under the curve for the change in the white blood cell count from T0 to T24 was 0.82. CONCLUSION: At initial sepsis evaluation (T0), both CBC and CRP should be performed to increase sensitivity. A highly negative predictive value is reachable with only two tests: a CBC at T0 and a CRP a T24.

Impact of the timing and the nature of nitrogen additions on the production kinetics of fermentative aromas by Saccharomyces cerevisiae during winemaking fermentation in synthetic media.

During alcoholic fermentation, many parameters, including the nitrogen composition of the must, can affect aroma production. The aim of this study was to examine the impact of several types of nitrogen sources added at different times during fermentation. Nitrogen was added as ammonium or a mixture of amino acids at the beginning of fermentation or at the start of the stationary phase. These conditions were tested with two Saccharomyces cerevisiae strains that have different nitrogen requirements. The additions systematically reduced the fermentation duration. The aroma production was impacted by both the timing of the addition and the composition of the nitrogen source. Propanol appeared to be a metabolic marker of the presence of assimilable nitrogen in the must. The production of ethyl esters was slightly higher after the addition of any type of nitrogen; the production of higher alcohols other than propanol was unchanged, and acetate esters were overproduced due to the overexpression of the genes ATF1 and ATF2. Finally the parameter affecting the most the synthesis of beneficial aromas was the addition timing: The supply of organic nitrogen at the beginning of the stationary phase was more favorable for the synthesis of beneficial aromas.

Oxygen availability and strain combination modulate yeast growth dynamics in mixed culture fermentations of grape must with Starmerella bacillaris and Saccharomyces cerevisiae.

Starmerella bacillaris (synonym Candida zemplinina) is a non-Saccharomyces yeast that has been proposed as a co-inoculant of selected Saccharomyces cerevisiae strains in mixed culture fermentations to enhance the analytical composition of the wines. In order to acquire further knowledge on the metabolic interactions between these two species, in this study we investigated the impact of oxygen addition and combination of Starm. bacillaris with S. cerevisiae strains on the microbial growth and metabolite production. Fermentations were carried out under two different conditions of oxygen availability. Oxygen availability and strain combination clearly influenced the population dynamics throughout the fermentation. Oxygen concentration increased the survival time of Starm. bacillaris and decreased the growth rate of S. cerevisiae strains in mixed culture fermentations, whereas it did not affect the growth of the latter in pure culture fermentations. This study reveals new knowledge about the influence of oxygen availability on the successional evolution of yeast species during wine fermentation.