Effect of yeast strain and some nutritional factors on tannin composition and potential astringency of model wines

Nine Saccharomyces cerevisiae cultures, isolated from different sources, were tested for their ability to reduce tannins reactive towards salivary proteins, and potentially responsible for wine astringency. Strains were preliminary genetically characterized and evaluated for physiological features of technological interest. Laboratory-scale fermentations were performed in three synthetic media: CT) containing enological grape tannin; CTP) CT supplemented with organic nitrogen sources; CTPV) CTP supplemented with vitamins. Adsorption of total tannins, tannins reactive towards salivary proteins, yellow pigments, phenolics having antioxidant activity, and total phenols, characterizing the enological tannin, was determined by spectrophotometric methods after fermentation. The presence of vitamins and peptones in musts greatly influenced the adsorption of tannins reactive towards salivary proteins (4.24 g/L gallic acid equivalent), thus promoting the reduction of the potential astringency of model wines. With reference to the different phenolic classes, yeast strains showed different adsorption abilities. From a technological point of view, the yeast choice proved to be crucial in determining changes in gustative and mouthfeel profile of red wines and may assist winemakers to modulate colour and astringency of wine.

Vγ9Vδ2 T-Cell Polyfunctionality Is Differently Modulated in HAART-Treated HIV Patients according to CD4 T-Cell Count

Alteration of γδ T-cell distribution and function in peripheral blood is among the earliest defects during HIV-infection. We asked whether the polyfunctional response could also be affected, and how this impairment could be associated to CD4 T-cell count. To this aim, we performed a cross-sectional study on HIV-infected individuals. In order to evaluate the polyfunctional-Vγ9Vδ2 T-cell response after phosphoantigen-stimulation, we assessed the cytokine/chemokine production and cytotoxicity by flow-cytometry in HAART-treated-HIV+ persons and healthy-donors. During HIV-infection Vγ9Vδ2-polyfunctional response quality is affected, since several Vγ9Vδ2 T-cell subsets resulted significantly lower in HIV+ patients in respect to healthy donors. Interestingly, we found a weak positive correlation between Vγ9Vδ2 T-cell-response and CD4 T-cell counts. By dividing the HIV+ patients according to CD4 T-cell count, we found that Low-CD4 patients expressed a lower number of two Vγ9Vδ2 T-cell subsets expressing MIP-1β in different combinations with other molecules (CD107a/IFNγ) in respect to High-CD4 individuals. Our results show that the Vγ9Vδ2 T-cell-response quality in Low-CD4 patients is specifically affected, suggesting a direct link between innate Vγ9Vδ2 T-cells and CD4 T-cell count. These findings suggest that Vγ9Vδ2 T-cell quality may be indirectly influenced by HAART therapy and could be included in a new therapeutical strategy which would perform an important role in fighting HIV infection.

Chip electrophoresis as a novel approach to measure the polyphenols reactivity toward human saliva

Saliva is a biological fluid with a multifunctional role that makes it interesting in terms of research and diagnostic possibilities. In food research, human saliva represented a useful tool by which we measure the tactile sensation elicited by polyphenol-rich beverages called astringency. A method based on SDS-PAGE analysis of saliva before and after the binding reaction with wine polyphenols has been successfully used in previous studies for measuring wine astringency by means of the saliva precipitation index. In this work, chip electrophoresis was used alternatively to SDS-PAGE and results were compared. Chip electrophoresis provides a very good reproducibility for wine and grape astringency. Moreover, this approach is much faster than the conventional SDS-PAGE method requiring several hours for an analysis. Another advantage over traditional gel is lower sample and reagent volume requirements, as well as the lower and less toxic wastes, contributing benefits to health and environment. The application of this novel method allowed, using the principal component analysis, to distinguish grapes and wines according to the saliva precipitation index and structural characteristics determined by the phoroglucinolysis analysis.

Bone marrow CD34+ progenitor cells may harbour HIV-DNA even in successfully treated patients

The issue about bone marrow hematopoietic progenitor cells harbouring HIV-DNA in infected patients is still under scrutiny. We studied nine HIV-infected individuals undergoing bone marrow aspiration for diagnostic purposes. In all patients, even in those receiving successful antiretroviral therapy for several years, HIV-DNA was detected in purified CD34+ lineage-bone marrow progenitor cells. This finding, although not conclusive due to the low number of patients examined, adds further evidence that current treatment strategies may be insufficient to resolve latent infection in bone marrow CD34+ hematopoietic progenitor cells.

Clinical activity of FOLFIRI plus cetuximab according to extended gene mutation status by next-generation sequencing: findings from the CAPRI-GOIM trial

BACKGROUND

Treatment with antiepidermal growth factor receptor (anti-EGFR) monoclonal antibodies has been restricted to metastatic colorectal cancer (mCRC) patients with RAS wild-type tumors. Next-generation sequencing (NGS) allows the assessment in a single analysis of a large number of gene alterations and might provide important predictive and prognostic information.

PATIENTS AND METHODS

In the CAPRI-GOIM trial, 340 KRAS exon 2 wild-type mCRC patients received first-line FOLFIRI plus cetuximab. Tumor samples (182/340, 53.5%) were assessed by NGS to search for mutations in 22 genes involved in colon cancer.

RESULTS

Objective responses in the NGS cohort were observed in 104/182 patients [overall response rate (ORR) 57.1%; 95% confidence interval (95% CI) 52% to 66.4%] with a median progression-free survival (mPFS) of 9.8 (95% CI 8.7-11.5) months. NGS analysis was successfully completed in all 182 samples. One or more gene mutations (up to five) were detected in 124/182 (68.1%) tumors within 14/22 genes for a total of 206 mutations. KRAS exon 2 mutations were identified in 29/182 (15.9%) samples, defined as wild type by local laboratory assessment. Frequently mutated genes were: TP53 (39.6%), KRAS exons 3/4 (8.8%), NRAS exons 2/3 (7.1%), PIK3CA exons 9/20 (13.2%), BRAF (8.2%). FOLFIRI plus cetuximab treatment determined ORR of 62.0% (95% CI 55.5% to 74.6%) with mPFS of 11.1 (95% CI 9.2-12.8) months in patients with KRAS and NRAS wild-type tumors. Conversely, ORR was 46.6% (95% CI 39.9-57.5%) with mPFS of 8.9 (95% CI 7.4-9.6) months in patients with KRAS or NRAS mutations. Similarly, the subgroup of patients carrying KRAS, NRAS, BRAF, or PIK3CA mutations showed a worse outcome, although this might be due to a prognostic effect.

CONCLUSIONS

This study demonstrates that NGS analysis in mCRC is feasible, reveals high level of intra and intertumor heterogeneity, and identifies patients that might benefit of FOLFIRI plus cetuximab treatment.

Modulation of polyfunctional HIV-specific CD8 T cells in patients responding differently to antiretroviral therapy

Antiretroviral therapy allows a restoration of immune cell homeostasis associated with a normal immune competence. Our goal was to analyze the modulation of polyfunctional HIV-specific CD8+ T-cell responses during antiretroviral therapy. HIV-infected individuals were divided into four groups according to CD4+ cell count and viral load at the moment of recruitment. Whole blood was stimulated with a pool of CD8-specific HIV-antigens to assess cytokine/chemokine production and cytotoxicity activity by using flow cytometry. The groups show different modulation in HIV-specific CD8+ T-cell responses. In particular, immunological failure showed different distributions of polyfunctional HIVspecific CD8+ responses, mainly due to an increase of cells producing CD107alpha/IFNgamma/IL-2/MIP-1beta. Our results indicate that this particular 4+ functional subset is a possible correlate of immunological failure. Considering the complexity of interactions among HAART, immune system and HIV, work is in progress to find correlates of therapy efficacy.

Innovative method for carbon dioxide determination in human postmortem cardiac gas samples using headspace-gas chromatography-mass spectrometry and stable labeled isotope as internal standard

A novel approach to measure carbon dioxide (CO2) in gaseous samples, based on a precise and accurate quantification by (13)CO2 internal standard generated in situ is presented. The main goal of this study was to provide an innovative headspace-gas chromatography-mass spectrometry (HS-GC-MS) method applicable in the routine determination of CO2. The main drawback of the GC methods discussed in the literature for CO2 measurement is the lack of a specific internal standard necessary to perform quantification. CO2 measurement is still quantified by external calibration without taking into account analytical problems which can often occur considering gaseous samples. To avoid the manipulation of a stable isotope-labeled gas, we have chosen to generate in situ an internal labeled standard gas ((13)CO2) on the basis of the stoichiometric formation of CO2 by the reaction of hydrochloric acid (HCl) with sodium hydrogen carbonate (NaH(13)CO3). This method allows a precise measurement of CO2 concentration and was validated on various human postmortem gas samples in order to study its efficiency.