2,345 research outputs found

    Characterization of wine fermentations using fiber optic-mediated UV-VIS-SWNIR spectroscopy

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    Spectroscopy is widely used in biological sciences, being applied to liquids, pastes, powders, films, fibers, gases and surfaces. It makes possible to characterize proteins, peptides, lipids, membranes and carbohydrates in pharmaceuticals, foods, plants or animal tissues. It can also provide detailed information about the structure and mechanism of action of molecules. UV-VIS-SWNIR spectroscopy has not been used for fermentations characterization. This is possibly attributed to the fact that UV-VIS spectroscopy records transmissions between electron energy levels from molecular orbitals, which do not have a direct relationship with the presence/concentration of compounds, instead of vibrational or structural oscillation of molecular groups as in the infrared region, where such relationship is more straightforward. UV-VIS-SWNIR spectroscopy registers many features such as fluorescence and vibrational resonances due to energy decay of exited electrons, which may provide highly accurate fingerprinting of metabolites and metabolic state of the fermentation, provided that an adequate data treatment and interpretation system is available. In this work we explore the use of fiber optics UV-VIS-SWNIR spectroscopy to characterize wine fermentations of a Saccharomyces cerevisiae collection. This collection comprises 114 strains (among which almost 40 are sequenced strains), between industrial strains used for winemaking, brewing, bakery, distillery (sake, cachaça) and ethanol production, natural isolates obtained in winemaking environments, and also strains from particular environments (e.g. pathogenic strains, isolates from insects, fruits and oak exudates). Individual fermentations were carried out in 100 mL wine (cv. Loureiro) must for each of the 114 strains, and the growth rate, CO2 release and glucose concentration were followed throughout fermentation. When glucose concentration was below 5 g/L, cells were collected and immediately frozen and stored for fiber optics spectroscopy analysis. Transmittance fiber optics UV-VIS-SWNIR spectroscopy was used to record the spectra between 200 and 1200 nm, using a highly sensitive scientific-grade spectrometer (Ocean Optics, QE65000) for maximum resolution. The procedure was performed in a special probe container designed to isolate the environmental light and maintain the probe horizontally, to prevent the deposition of debris in the mirrored surface. The following experimental procedure was performed: spectra were obtained at room temperature at previously stabilized (20 min) light sources; dark spectra were recorded and measurements were taken with linear and electric dark correction. Light spectra were statistically monitored, assessing the reproducibility of the light source by regular light measurements. Twenty spectra replicates were recorded for each fermentation. Results show that after appropriate preprocessing and signal classification, fiber optics UV-VIS-SWNIR spectroscopy is a robust technique for characterize different wine fermentations, being able to characterize and differentiate the fermentation of different strains of S. cerevisiae based on their origins, by each spectroscopic fingerprinting. This technique associated with other physico-chemical information can benefit the creation of an information system capable of providing extremely detailed information about physical processes and molecular biology that will aid both scientists and engineers to study and develop new biotechnological products.Fundação para a Ciência e a Tecnologia (FCT

    Genotypic and pheno-metabolomic characterization of a Saccharomyces cerevisiae strain collection

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    The objective of the present work was to gain a deeper understanding of the phenotypic diversity of natural isolates of Saccharomyces cerevisiae, using high-throughput methods in combination with bioanalytical data. A S. cerevisiae strain collection was constituted comprising 187 strains from different geographical origins and technological uses. Some microsatellite alleles and phenotypes were identified as responsible for the highest strain variability. All strains were used for fermentation with white grapes must, and final fermentation products were analysed using fiber optics spectroscopy and bioanalytical quantification. Inter-strain aromatic profiles (primary fermentation products, higher alcohols, esters, fatty acids) were discriminated by HPLC and GC-MS. Relating the metabolic signature of the strains with phenotypic and genetic data by computational analysis is a pre-requisite to obtain a holistic overview of yeast pheno-metabolomics.O objectivo do presente trabalho consistiu em explorar a diversidade fenotípica de isolados naturais de Saccharomyces cerevisiae, através de métodos de alto débito combinados com dados bioanalíticos. Uma colecção de 187 estirpes de S. cerevisiae foi constituída com isolados de origens geográficas e aplicações tecnológicas diferentes. Alguns alelos de microssatélites e alguns fenótipos foram identificados como responsáveis pela grande variabilidade entre estirpes. Todas as estirpes foram usadas para fermentações em mosto de uvas brancas, e os produtos finais de fermentação foram analisados usando espectroscopia de fibra óptica e quantificação bioanalítica. Os perfis aromáticos entre estirpes (produtos de fermentação primários, álcoois superiores, esteres, ácidos gordos) foram descriminados por HPLC e GC-MS. A relação, através de abordagens computacionais, entre a assinatura metabólica das estirpes e os dados fenotípicos e genotípicos, é um pré-requisito para obter uma visão holística do feno-metaboloma da levedura.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/48591/2008, SFRH/BD/46737/2008, SFRH/BD/48616/2008, SFRH/BD/74798/2010

    Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis.

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    Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that genetic factors are primarily responsible for the substantially increased frequency of the disease seen in the relatives of affected individuals, and systematic attempts to identify linkage in multiplex families have confirmed that variation within the major histocompatibility complex (MHC) exerts the greatest individual effect on risk. Modestly powered genome-wide association studies (GWAS) have enabled more than 20 additional risk loci to be identified and have shown that multiple variants exerting modest individual effects have a key role in disease susceptibility. Most of the genetic architecture underlying susceptibility to the disease remains to be defined and is anticipated to require the analysis of sample sizes that are beyond the numbers currently available to individual research groups. In a collaborative GWAS involving 9,772 cases of European descent collected by 23 research groups working in 15 different countries, we have replicated almost all of the previously suggested associations and identified at least a further 29 novel susceptibility loci. Within the MHC we have refined the identity of the HLA-DRB1 risk alleles and confirmed that variation in the HLA-A gene underlies the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis

    Development and Psychometric Validation of the Pandemic-Related Traumatic Stress Scale for Children and Adults

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    To assess the public health impact of the COVID-19 pandemic on mental health, investigators from the National Institutes of Health Environmental influences on Child Health Outcomes (ECHO) research program developed the Pandemic-Related Traumatic Stress Scale (PTSS). Based on the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) acute stress disorder symptom criteria, the PTSS is designed for adolescent (13–21 years) and adult self-report and caregiver-report on 3–12-year-olds. To evaluate psychometric properties, we used PTSS data collected between April 2020 and August 2021 from non-pregnant adult caregivers (n = 11,483), pregnant/postpartum individuals (n = 1,656), adolescents (n = 1,795), and caregivers reporting on 3–12-year-olds (n = 2,896). We used Mokken scale analysis to examine unidimensionality and reliability, Pearson correlations to evaluate relationships with other relevant variables, and analyses of variance to identify regional, age, and sex differences. Mokken analysis resulted in a moderately strong, unidimensional scale that retained nine of the original 10 items. We detected small to moderate positive associations with depression, anxiety, and general stress, and negative associations with life satisfaction. Adult caregivers had the highest PTSS scores, followed by adolescents, pregnant/postpartum individuals, and children. Caregivers of younger children, females, and older youth had higher PTSS scores compared to caregivers of older children, males, and younger youth, respectively

    Global patterns in endemicity and vulnerability of soil fungi

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    Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms

    Global patterns in endemicity and vulnerability of soil fungi

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    Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms

    Abstracts of presentations on plant protection issues at the fifth international Mango Symposium Abstracts of presentations on plant protection issues at the Xth international congress of Virology: September 1-6, 1996 Dan Panorama Hotel, Tel Aviv, Israel August 11-16, 1996 Binyanei haoma, Jerusalem, Israel

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