439 research outputs found

    Research on the reduction of SO2 doses in winemaking using lysozyme and oenological tannin

    Get PDF
    The effect of reducing the dose of sulfur dioxide on the physico-chemical and organoleptic properties of wines with Murfatlar controlled designation of origin was studied in this paper, experimenting with different prefermentative oenological treatments. For this purpose, a series of experimental variants was carried out on two Romanian grape cultivars for white wines ('Fetească regală') and red wines ('Fetească neagră'), using two yeast strains that produce low amounts of SO2 (Saccharomyces cerevisiae var. bayanus and Metschnikowia pulcherrima, a Non-Saccharomyces strain) and four prefermentative treatments with different doses of sulfur dioxide, lysozyme and oenological tannin. The obtained results highlighted the fact that reducing the dose of sulfur dioxide using lysozyme and oenological tannin can provide oxidative protection during the alcoholic fermentation stage, improving the organoleptic characteristics of white and red wines. From the physico-chemical point of view, the wines did not show statistically significant differences, except for the color intensity, which was higher in the case of the variants supplemented with 500 mg/L lysozymes, for both of the yeast strains used for fermentation. This study encourages the continuation of research regarding the experimentation of alternative products, to reduce the sulfur dioxide normally used in the winemaking process, in order to obtain healthy products, in accordance with current consumer requirements

    Understanding the stigma of psychosis in ethnic minority groups: A qualitative exploration

    Get PDF
    Psychosis is a mental health difficulty which is widely stigmatized. The stigma of psychosis can lead to detrimental consequences and cause further distress. The aim of this study was to explore the experience of stigma and discrimination of psychosis from the perspective of service users from ethnic minority backgrounds. A total of 21 semistructured interviews were conducted with service users with psychosis from ethnic minority backgrounds examining their experiences of stigma from psychosis. Qualitative data were analyzed using thematic analysis. Five superordinate themes were identified, “social and cultural context of stigma,” “stigma is a family problem,” “stigma and discrimination within mental health services,” “intrapersonal impacts,” and “managing stigma within relationships.” Stigma is a significant concern for people with psychosis from an ethnic minority background. It is important that stigma and discrimination are appropriately assessed and considered within the care of people from ethnic minority backgrounds

    A robust prognostic signature for hormone-positive node-negative breast cancer

    Get PDF
    BACKGROUND: Systemic chemotherapy in the adjuvant setting can cure breast cancer in some patients that would otherwise recur with incurable, metastatic disease. However, since only a fraction of patients would have recurrence after surgery alone, the challenge is to stratify high-risk patients (who stand to benefit from systemic chemotherapy) from low-risk patients (who can safely be spared treatment related toxicities and costs). METHODS: We focus here on risk stratification in node-negative, ER-positive, HER2-negative breast cancer. We use a large database of publicly available microarray datasets to build a random forests classifier and develop a robust multi-gene mRNA transcription-based predictor of relapse free survival at 10 years, which we call the Random Forests Relapse Score (RFRS). Performance was assessed by internal cross-validation, multiple independent data sets, and comparison to existing algorithms using receiver-operating characteristic and Kaplan-Meier survival analysis. Internal redundancy of features was determined using k-means clustering to define optimal signatures with smaller numbers of primary genes, each with multiple alternates. RESULTS: Internal OOB cross-validation for the initial (full-gene-set) model on training data reported an ROC AUC of 0.704, which was comparable to or better than those reported previously or obtained by applying existing methods to our dataset. Three risk groups with probability cutoffs for low, intermediate, and high-risk were defined. Survival analysis determined a highly significant difference in relapse rate between these risk groups. Validation of the models against independent test datasets showed highly similar results. Smaller 17-gene and 8-gene optimized models were also developed with minimal reduction in performance. Furthermore, the signature was shown to be almost equally effective on both hormone-treated and untreated patients. CONCLUSIONS: RFRS allows flexibility in both the number and identity of genes utilized from thousands to as few as 17 or eight genes, each with multiple alternatives. The RFRS reports a probability score strongly correlated with risk of relapse. This score could therefore be used to assign systemic chemotherapy specifically to those high-risk patients most likely to benefit from further treatment

    Engineering long-range order in supramolecular assemblies on surfaces : the paramount role of internal double bonds in discrete long-chain naphthalenediimides

    Get PDF
    Achieving long-range order with surface-supported supramolecular assemblies is one of the pressing challenges in the prospering field of non-covalent surface functionalization. Having access to defect-free on-surface molecular assemblies will pave the way for various nanotechnology applications. Here we report the synthesis of two libraries of naphthalenediimides (NDIs) symmetrically functionalized with long aliphatic chains (C28 and C33) and their self-assembly at the 1-phenyloctane/highly oriented pyrolytic graphite (1-PO/HOPG) interface. The two NDI libraries differ by the presence/absence of an internal double bond in each aliphatic chain (unsaturated and saturated compounds, respectively). All molecules assemble into lamellar arrangements, with the NDI cores lying flat and forming 1D rows on the surface, while the carbon chains separate the 1D rows from each other. Importantly, the presence of the unsaturation plays a dominant role in the arrangement of the aliphatic chains, as it exclusively favors interdigitation. The fully saturated tails, instead, self-assemble into a combination of either interdigitated or non-interdigitated diagonal arrangements. This difference in packing is spectacularly amplified at the whole surface level and results in almost defect-free self-assembled monolayers for the unsaturated compounds. In contrast, the monolayers of the saturated counterparts are globally disordered, even though they locally preserve the lamellar arrangements. The experimental observations are supported by computational studies and are rationalized in terms of stronger van der Waals interactions in the case of the unsaturated compounds. Our investigation reveals the paramount role played by internal double bonds on the self-assembly of discrete large molecules at the liquid/solid interface

    Treatment with class a CpG oligodeoxynucleotides in cats with naturally occurring feline parvovirus infection: A prospective study

    Get PDF
    Feline parvovirus (FPV) causes severe gastroenteritis and leukopenia in cats; the outcome is poor. Information regarding specific treatments is lacking. Class A CpG oligodeoxynucleotides (CpG-A) are short single-stranded DNAs, stimulating type I interferon production. In cats, CpG-A induced an antiviral response in vivo and inhibited FPV replication in vitro. The aim was to prospectively investigate the effects of CpG-A on survival, clinical score, hematological findings, antiviral response (cytokines), viremia, and fecal shedding (real-time qPCR) in cats naturally infected with FPV. Forty-two FPV-infected cats were randomized to receive 100 g/kg of CpG-A (n = 22) or placebo (n = 20) subcutaneously, on admission and after 48 h. Blood and fecal samples were collected on admission, after 1, 3, and 7 days. All 22 cats showed short duration pain during CpG-A injections. The survival rate, clinical score, leukocyte and erythrocyte counts, viremia, and fecal shedding at any time-point did not differ between cats treated with CpG-A (50%) and placebo (40%). Antiviral myxovirus resistance (Mx) gene transcription increased in both groups from day 1 to 3 (p = 0.005). Antibodies against FPV on admission were associated with survival in cats (p = 0.002). In conclusion, CpG-A treatment did not improve the outcome in cats with FPV infection. FPV infection produced an antiviral response

    Electrochemical evaluation of dsDNA—Liposomes interactions

    Get PDF
    The aim of the present work was to evaluate the interaction between double-stranded DNA (dsDNA) and liposomes by voltammetric methods. The experimental results were analyzed considering the initial studies regarding the oxidation mechanism of dsDNA purine bases by cyclic and differential pulse voltammetry at the glassy carbon electrode (GCE). The interaction between dsDNA and 1,2-Dimyristoyl-sn-glycero-3-phosphocholine (DMPC) was studied in a suspension containing both dsDNA and DMPC liposomes, prepared in pH = 7.0, 0.1 M phosphate buffer and using different incubation time periods. The formation of dsDNA-liposome complex was put in evidence by the decrease of the dsDNA oxidation peaks, dependent upon the incubation time. This behavior was explained considering the electroactive centers of dsDNA, guanosine monophosphate and adenosine monophosphate residues, part of them hidden inside the dsDNA-liposome complex structure and thus being unable to reach the GC electrode and preventing their oxidation. The electrochemical results are relevant for a better physicochemical characterisation of the dsDNA and dsDNA-liposome complex, which can be important for the development of gene therapy vectors

    Effect of Pretreatment Method on the Nanostructure and Performance of Supported Co Catalysts in Fischer−Tropsch Synthesis

    Get PDF
    ABSTRACT: Understanding precursor transformation to active catalysts is crucial to heterogeneous Fischer−Tropsch (FT) catalysis directed toward production of hydrocarbons for transportation fuels. Despite considerable literature on FT catalysis, the effect of pretreatment of supported cobalt catalysts on cobalt dispersion, dynamic atomic structure, and the activity of the catalysts is not well understood. Here we present systematic studies into the formation of active catalyst phases in supported Co catalyst precursors in FT catalysis using in situ environmental (scanning) transmission electron microscopy (E(S)TEM) with single-atom resolution under controlled reaction environments for in situ visualization, imaging, and analysis of reacting atomic species in real time, EXAFS, XAS, DRIFTS analyses, and catalytic activity measurements. We have synthesized and analyzed dried reduced (D) and dried calcined reduced (DC) Co real catalysts on reducible and nonreducible supports, such as SiO2, Al2O3, TiO2, and ZrO2. Comparisons of dynamic in situ atomic structural observations of reacting single atoms, atomic clusters, and nanoparticles of Co and DRIFTS, XAS, EXAFS, and catalytic activity data of the D and DC samples reveal in most cases better dispersion in the D samples, leading to a larger number of low-coordination Co0 sites and a higher number of active sites for CO adsorption. The experimental findings on the degree of reduction of D and 27 DC catalysts on reducible and nonreducible supports and correlations between hexagonal (hcp) Co sites and the activity of the catalysts generate structural insights into the catalyst dynamics, important to the development of efficient FT catalysts

    High activity redox catalysts synthesized by chemical vapor impregnation

    Get PDF
    The use of precious metals in heterogeneous catalysis relies on the preparation of small nanoparticles that are stable under reaction conditions. To date, most conventional routes used to prepare noble metal nanoparticles have drawbacks related to surface contamination, particle agglomeration, and reproducibility restraints. We have prepared titania-supported palladium (Pd) and platinum (Pt) catalysts using a simplified vapor deposition technique termed chemical vapor impregnation (CVI) that can be performed in any standard chemical laboratory. These materials, composed of nanoparticles typically below 3 nm in size, show remarkable activity under mild conditions for oxidation and hydrogenation reactions of industrial importance. We demonstrate the preparation of bimetallic Pd–Pt homogeneous alloy nanoparticles by this new CVI method, which show synergistic effects in toluene oxidation. The versatility of our CVI methodology to be able to tailor the composition and morphology of supported nanoparticles in an easily accessible and scalable manner is further demonstrated by the synthesis of Pdshell–Aucore nanoparticles using CVI deposition of Pd onto preformed Au nanoparticles supported on titania (prepared by sol immobilization) in addition to the presence of monometallic Au and Pd nanoparticles

    Modeling precision treatment of breast cancer

    Get PDF
    Background: First-generation molecular profiles for human breast cancers have enabled the identification of features that can predict therapeutic response; however, little is known about how the various data types can best be combined to yield optimal predictors. Collections of breast cancer cell lines mirror many aspects of breast cancer molecular pathobiology, and measurements of their omic and biological therapeutic responses are well-suited for development of strategies to identify the most predictive molecular feature sets. Results: We used least squares-support vector machines and random forest algorithms to identify molecular features associated with responses of a collection of 70 breast cancer cell lines to 90 experimental or approved therapeutic agents. The datasets analyzed included measurements of copy number aberrations, mutations, gene and isoform expression, promoter methylation and protein expression. Transcriptional subtype contributed strongly to response predictors for 25% of compounds, and adding other molecular data types improved prediction for 65%. No single molecular dataset consistently out-performed the others, suggesting that therapeutic response is mediated at multiple levels in the genome. Response predictors were developed and applied to TCGA data, and were found to be present in subsets of those patient samples. Conclusions: These results suggest that matching patients to treatments based on transcriptional subtype will improve response rates, and inclusion of additional features from other profiling data types may provide additional benefit. Further, we suggest a systems biology strategy for guiding clinical trials so that patient cohorts most likely to respond to new therapies may be more efficiently identified
    corecore