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Hydroxytyrosol (HT) is a phenolic compound of recognized bioactivity that has been described in wines but little is known about its origin. This work demonstrates that yeast involved in wine making, i.e. Saccharomyces cerevisiae strains and the non- Saccharomyces Torulaspora delbrueckii , can synthesise HT, as this compound was identified in the intracellular media of three strains by means of a developed and validated UHPLC–HRMS method with LOQ and LOD of 0.108 and 0.035 ng mL −1 respectively. Controlled fermentations were performed with different varieties of grapes ( Corredera , Moscatel , Chardonnay , Palomino fino , Sauvignon Blanc , Vijiriega , and Tempranillo ) and synthetic must. The Saccharomyces cerevisiae strain QA23 was the most efficient producer of HT from tested yeasts. On the other hand, the grape variety influences HT wine concentrations. Furthermore, the maximum concentration of HT is reached between the fourth and sixth day of fermentation. This work reveals that yeasts have a great potential for the production of HT. [ABSTRACT FROM AUTHOR]

Melatonin is a neurohormone involved in the regulation of circadian rhythms in humans. Evidence has recently been found of its occurrence in wines and its role in the winemaking process. The yeast Saccharomyces cerevisiae is consequently thought to be important in Melatonin synthesis, but limited data and reference texts are available on this synthetic pathway. This paper aims to elucidate whether the synthetic pathway of Melatonin in Saccharomyces and non-Saccharomyces strains involves these intermediates. To this end, seven commercial strains comprising Saccharomyces cerevisiae (Red Fruit, ES488, Lalvin QA23, Uvaferm BC, and Lalvin ICV GRE) and non-Saccharomyces ( Torulaspora delbrueckii and Metschnikowia pulcherrima ) were monitored, under controlled fermentation conditions, in synthetic must, for seven days. Samples were analysed using a UHPLC—HRMS system (Qexactive). Five out of the seven strains formed Melatonin during the fermentation process: three S. cerevisiae strains and the two non-Saccharomyces. Additionally, other compounds derived from l -tryptophan occurred during fermentation. [ABSTRACT FROM AUTHOR]

• The efficiency of three methods of intracellular extraction was evaluated. • Two UHPLC/MS methods were validated to measure metabolites related to tryptophan–tyrosine. • Removing phospholipids and proteins enabling obtain good values for matrix effects. • Higher temperatures of the extraction methods produce overestimating of extracted amino acids. • Extractions at low temperatures had a better efficiency and satisfactory repeatability values. Yeast nitrogen metabolism produces metabolites, whose origin in wines has scarcely been studied, with an important biological and organoleptic role. The present work focuses on comparing three intracellular extraction methods in order to elucidate efficiency of extraction while measuring the effect of temperature upon the integrity of the compounds related to the metabolism of tryptophan and tyrosine by yeast. Two UHPLC/HRMS methods to measure 16 metabolites were developed and validated. The validation provided optimum values of LOD (7.4·10−6 to 0.1 μg L−1), of LOQ (2·10−5 to 0.02 μg L−1) of precision (11–0.5% RSD) and repeatability (12–0.5% RSD). The removal of interfering molecules enabled matrix effects to be kept at low levels. The results pointed out that the low-temperature methods were more effective, providing better precision for 16 metabolites. The high-temperature extraction method may yield false enhanced compounds concentrations since they originate in cell wall macromolecules degradation. [ABSTRACT FROM AUTHOR]

Summary: Development of polyfunctional T lymphocyte responses is critical in the immunological response against HIV-1. Fifty-four HIV-1 infected patients receiving antiretroviral treatment (ART) and immunization with an HIV-1 immunogen or placebo, periodically every 3 months throughout a period of 36 months, were evaluated for the purposes of analysing the development of HIV-1-specific CD4+ and CD8+ responses. A significant increase of proliferating and IFN-γ producing CD8+ HIV-1-specific T cells, of HIV-1-specific precursor frequencies for CD8+ and for CD4+ T cells and of Gag/pol-specific memory CTL precursors (CTLp) was observed in the immunogen group in comparison to placebo. IL-2 intracellular expression and IFN-γ and TNF-α co-expression in HIV-1-specific CD8+ T cells were also substantially increased in the immunized group. A negative correlation between viral load and CD3+CD4+CFSElow HIV-1-specific lymphoproliferative response and frequency of Gag/pol-specific CTLp was solely observed in the HIV-1 immunogen group. Long-term immunization in patients receiving ART helps to develop HIV-1-specific polyfunctional T cell responses. [Copyright &y& Elsevier]

Abstract: An increased risk of invasive pneumococcal infection has been described among adult heart transplant (HT) recipients. Vaccination has been recommended before HT but the appropriate time for revaccination is not known. In a preliminary analysis of a prospective study involving a cohort of 32 HT recipients receiving daclizumab and triple immunosuppresion therapy, a progressive decline in pneumococcal polysaccharide antibody (anti-PPS) levels was observed during the first year after HT. One of the patients who was found to have a decrease in the levels of anti-PPS developed severe pneumococcal meningitis 20 months after HT. Before HT he had received non-conjugated 23-valent pneumococcal vaccine and showed a normal post-immunization anti-PPS production. The data suggest that long-term immunologic monitoring might be useful to recognize impairment of antibody responses under immunosuppressive therapy in HT. [Copyright &y& Elsevier]

Abstract: Objective: We aimed to assess humoral immunity markers that provide prognostic value for the development of infections in heart transplant recipients. Patients and methods: Forty-one heart transplant recipients underwent humoral immunity studies, including Immunoglobulin (IgG, IgA, IgM) and IgG subclasses determined by nephelometry on serum samples obtained before transplantation and 1 month after transplantation. Potential clinical risk factors were evaluated: waiting time for transplantation, pretransplant cytomegalovirus (CMV) serologic status of donor and recipient; recipient age; gender; cardiac disease severity before transplantation; type of immunosuppression; and occurrence of rejection. Outcome measures: We measured infections requiring intravenous (IV) drug therapy during the first year. The association between variables and outcome was assessed using Cox proportional hazards modelling. Immunoglobulin levels were split into two groups using the median value observed as the cut-off. Results: Of 41 patients studied, 19 (46%) had at least one episode of infection, 16 of which were CMV infections treated with IV gancyclovir, 1 CMV disease + aspergillosis and 2 bacterial pneumonia. Pretransplant IgG (<1055 mg/dL; RR 5.32; 95% confidence interval [CI] 1.73 to 16.29; P = .0034); pretransplant IgG1 (<695 mg/dL; RR 4.80; CI 1.57 to 14.68; P = .006), and posttransplant IgG levels (<589 mg/dL; RR 3.38; CI 1.21 to 9.44, P = .019) were associated with an increased risk of developing infections. Both waiting time for transplantation (RR 0.95; CI 0.91 to 0.98, P = .007) and pretransplant cardiac disease severity (RR 1.94; CI 1.17 to 3.21, P = .009) were significant risk factors for infection. After adjustment for clinical predictive variables, decreased values of posttransplant IgG remained significant predictors. Conclusions: The existence of decreased levels of IgG in the setting of heart transplantation was associated with an higher risk for infection. Monitoring of immunoglobulin levels, a rapid and well-standardized nephelometric determination, in heart transplantation, may identify a subset of patients at risk for development of infections. [Copyright &y& Elsevier]

Abstract: Secondary hypogammaglobulinemia after heart transplantation may follow immunosuppressive therapy with the resultant increased risk of infections, including cytomegalovirus (CMV) disease. There is limited information on the use of intravenous immunoglobulin replacement therapy (IVIG) in heart-transplanted patients with hypogammaglobulinemia and CMV disease. We present data on five consecutive heart-transplanted patients with relapsing CMV disease, four of whom developed gastrointestinal disease. The immunosuppressive regimen included prednisone, cyclosporine A, azathioprine, mycophenolate mofetil, tacrolimus and antithymocyte globulin (ATG). Evaluation revealed CMV antigenemia. All the patients had been treated with intravenous ganciclovir. In addition, hyperimmune CMV immunoglobulin was administered in three patients. Significantly reduced levels of immunoglobulin G (IgG) were observed in the patients as compared with 15 heart-transplanted individuals without CMV disease [mean IgG levels: 323±18 and 639±63 mg/dl, respectively (p=0.003)]. IVIG [FLEBOGAMMA], 200–400 mg/kg every 21 days with the goal of maintaining normal serum IgG levels, was added for the treatment of CMV disease. Selected batches with the highest anti-CMV titers were set apart for the treatment of the patients. IVIG treatment, in combination with antiviral therapy, proved able to control CMV disease. There was a favorable clinical response and the patients became free of gastrointestinal symptoms. Detection of CMV antigens was negative after treatment. During IVIG therapy no immediate or delayed adverse effects were observed. Even if our survey was limited to five cases, the results suggest that addition of IVIG to antiviral chemotherapy might improve outcome in heart-transplanted patients with hypogammaglobulinemia and CMV disease. [Copyright &y& Elsevier]