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1.
New Phytol ; 242(2): 392-423, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38409806

RESUMO

A minuscule fraction of the Earth's paleobiological diversity is preserved in the geological record as fossils. What plant remnants have withstood taphonomic filtering, fragmentation, and alteration in their journey to become part of the fossil record provide unique information on how plants functioned in paleo-ecosystems through their traits. Plant traits are measurable morphological, anatomical, physiological, biochemical, or phenological characteristics that potentially affect their environment and fitness. Here, we review the rich literature of paleobotany, through the lens of contemporary trait-based ecology, to evaluate which well-established extant plant traits hold the greatest promise for application to fossils. In particular, we focus on fossil plant functional traits, those measurable properties of leaf, stem, reproductive, or whole plant fossils that offer insights into the functioning of the plant when alive. The limitations of a trait-based approach in paleobotany are considerable. However, in our critical assessment of over 30 extant traits we present an initial, semi-quantitative ranking of 26 paleo-functional traits based on taphonomic and methodological criteria on the potential of those traits to impact Earth system processes, and for that impact to be quantifiable. We demonstrate how valuable inferences on paleo-ecosystem processes (pollination biology, herbivory), past nutrient cycles, paleobiogeography, paleo-demography (life history), and Earth system history can be derived through the application of paleo-functional traits to fossil plants.


Assuntos
Ecossistema , Fósseis , Ecologia , Plantas , Fenótipo
2.
J Hum Nutr Diet ; 36(4): 1339-1348, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36794574

RESUMO

BACKGROUND: Parental child-feeding practices have been associated with child body mass index (BMI) and specific food group consumption; however, their role in the development of dietary patterns is less understood. We aim to study the association between parental child-feeding practices at 4 years old and dietary patterns at 7 years that explain BMI z-scores at age 10. METHODS: Participants were children from the Generation XXI birth cohort (n = 3272). Three patterns of feeding practices at 4 years were previously identified: 'Perceived monitoring', 'Restriction' and 'Pressure to eat'. At 7 years, two dietary patterns were derived: 'Energy-dense foods', higher consumption of energy-dense foods and drinks and processed meats and lower consumption of vegetable soup (significantly associated with BMI z-scores at 10 years) and 'Fish-based', higher in fishery intake and lower in energy-dense food intake. Associations were estimated by linear regression models, adjusted for potential confounders (mother's age, education and pre-pregnancy BMI). RESULTS: Girls whose parents used more Restriction, Perceived monitoring and Pressure to eat at 4 years were less likely to follow the 'Energy-dense foods' dietary pattern at 7 years (ß̂ = -0.082; 95% confidence intervals [CI]: -0.134; -0.029; ß̂ = -0.093; 95% CI: -0.146; -0.039; ß̂ = -0.079; 95% CI: -0.135; -0.04, respectively). In both sexes, children whose parents used more Restriction and Perceived monitoring at 4 years were more likely to follow the 'Fish-based' dietary pattern at 7 years (girls: ß̂ = 0.143; 95% CI: 0.077; 0.210; ß̂ = 0.079; 95% CI: 0.011; 0.148; boys: ß̂ = 0.157; 95% CI: 0.090; 0.224; ß̂ = 0.104; 95% CI: 0.041; 0.168). CONCLUSIONS: Children whose parents used more Restriction and Perceived monitoring at preschool age were more likely to follow healthier dietary patterns at age 7.


Assuntos
Dieta , Comportamento Alimentar , Masculino , Feminino , Gravidez , Animais , Humanos , Pré-Escolar , Índice de Massa Corporal , Pais , Verduras , Inquéritos e Questionários
3.
Appetite ; 171: 105909, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34986399

RESUMO

Early feeding practices have been related to child's body mass index (BMI), however, their role in establishing dietary patterns is less well understood. The aim of this study was to examine the association of parent-reported early feeding practices (breastfeeding duration, type of foods and timing of complementary feeding) and dietary patterns identified at age 7 to explain BMI z-scores at 10 years of age. Participants were children from the Generation XXI cohort, evaluated at 4, 7 and 10 years of age (n = 3673). At 7 years-old, dietary intake was assessed with a validated food-frequency questionnaire. Two dietary patterns were previously derived: "Energy-dense foods" (higher in energy-dense foods, and lower in vegetable soup, significantly associated with BMI z-score at 10 years-old, and the "Fish-based" dietary pattern (higher in fish consumption and low in energy-dense foods). Adjusted sex-stratified associations were estimated by generalized linear models. Boys and girls who were never breastfed or were breastfed for a very short duration had lower scores in the "Fish-based" dietary pattern, compared to those with longer breastfeeding durations (Boys: ß = -0.219; 95%CI: 0.361; -0.077; Girls: ß = -0.223; 95%CI: 0.358; -0.088). No significant associations between breastfeeding and the "Energy-dense foods" dietary pattern were found. Boys and girls who were offered cereals as a first food during complementary feeding, in comparison with soup, presented lower scores in the "Energy-dense foods" dietary pattern (Boys: ß = -0.183; 95%CI: 0.292; -0.074; Girls: ß = -0.155; 95%CI: 0.259; -0.050), but only girls presented higher scores in the 'Fish-based' dietary pattern (ß = 0.137; 95%CI: 0.006; 0.267). The age of introduction of complementary feeding was not significantly associated with the dietary patterns. Parents should be supported in their infant feeding decisions, given the potential effects of breastfeeding duration and first foods at complementary feeding on shaping longer term dietary patterns of young children.


Assuntos
Coorte de Nascimento , Comportamento Alimentar , Índice de Massa Corporal , Aleitamento Materno , Pré-Escolar , Dieta , Feminino , Humanos , Lactente , Verduras
4.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360763

RESUMO

Immobilised dye-decolorizing peroxidases (DyPs) are promising biocatalysts for the development of biotechnological devices such as biosensors for the detection of H2O2. To this end, these enzymes have to preserve native, solution properties upon immobilisation on the electrode surface. In this work, DyPs from Cellulomonas bogoriensis (CboDyP), Streptomyces coelicolor (ScoDyP) and Thermobifida fusca (TfuDyP) are immobilised on biocompatible silver electrodes functionalized with alkanethiols. Their structural, redox and catalytic properties upon immobilisation are evaluated by surface-enhanced resonance Raman (SERR) spectroelectrochemistry and cyclic voltammetry. Among the studied electrode/DyP constructs, only CboDyP shows preserved native structure upon attachment to the electrode. However, a comparison of the redox potentials of the enzyme in solution and immobilised states reveals a large discrepancy, and the enzyme shows no electrocatalytic activity in the presence of H2O2. While some immobilised DyPs outperform existing peroxidase-based biosensors, others fail to fulfil the essential requirements that guarantee their applicability in the immobilised state. The capacity of SERR spectroelectrochemistry for fast screening of the performance of immobilised heme enzymes places it in the front-line of experimental approaches that can advance the search for promising DyP candidates.


Assuntos
Bactérias/enzimologia , Proteínas de Bactérias/química , Técnicas Biossensoriais , Enzimas Imobilizadas/química , Peroxidase/química , Catálise , Eletrodos
5.
Molecules ; 26(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34443440

RESUMO

Vibrational spectroscopy and in particular, resonance Raman (RR) spectroscopy, can provide molecular details on metalloproteins containing multiple cofactors, which are often challenging for other spectroscopies. Due to distinct spectroscopic fingerprints, RR spectroscopy has a unique capacity to monitor simultaneously and independently different metal cofactors that can have particular roles in metalloproteins. These include e.g., (i) different types of hemes, for instance hemes c, a and a3 in caa3-type oxygen reductases, (ii) distinct spin populations, such as electron transfer (ET) low-spin (LS) and catalytic high-spin (HS) hemes in nitrite reductases, (iii) different types of Fe-S clusters, such as 3Fe-4S and 4Fe-4S centers in di-cluster ferredoxins, and (iv) bi-metallic center and ET Fe-S clusters in hydrogenases. IR spectroscopy can provide unmatched molecular details on specific enzymes like hydrogenases that possess catalytic centers coordinated by CO and CN- ligands, which exhibit spectrally well separated IR bands. This article reviews the work on metalloproteins for which vibrational spectroscopy has ensured advances in understanding structural and mechanistic properties, including multiple heme-containing proteins, such as nitrite reductases that house a notable total of 28 hemes in a functional unit, respiratory chain complexes, and hydrogenases that carry out the most fundamental functions in cells.


Assuntos
Metaloproteínas/química , Análise Espectral Raman , Heme/química , Proteínas Ferro-Enxofre/química , Oxirredução , Espectrofotometria Infravermelho
6.
Microb Cell Fact ; 14: 124, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26314747

RESUMO

BACKGROUND: The introduction of yeast starter cultures consisting in a blend of Saccharomyces cerevisiae and non-Saccharomyces yeast strains is emerging for production of wines with improved complexity of flavor. The rational use of this approach is, however, dependent on knowing the impact that co-inoculation has in the physiology of S. cerevisiae. In this work the transcriptome of S. cerevisiae was monitored throughout a wine fermentation, carried out in single culture or in a consortium with Hanseniaspora guilliermondii, this being the first time that this relevant yeast-yeast interaction is examined at a genomic scale. RESULTS: Co-inoculation with H. guilliermondii reduced the overall genome-wide transcriptional response of S. cerevisiae throughout the fermentation, which was attributable to a lower fermentative activity of S. cerevisiae while in the mixed-fermentation. Approximately 350 genes S. cerevisiae genes were found to be differently expressed (FDR < 0.05) in response to the presence of H. guilliermondii in the fermentation medium. Genes involved in biosynthesis of vitamins were enriched among those up-regulated in the mixed-culture fermentation, while genes related with the uptake and biosynthesis of amino acids were enriched among those more expressed in the single-culture. The differences in the aromatic profiles of wines obtained in the single and in the mixed-fermentations correlated with the differential expression of S. cerevisiae genes encoding enzymes required for formation of aroma compounds. CONCLUSIONS: By integrating results obtained in the transcriptomic analysis performed with physiological data our study provided, for the first time, an integrated view into the adaptive responses of S. cerevisiae to the challenging environment of mixed culture fermentation. The availability of nutrients, in particular, of nitrogen and vitamins, stands out as a factor that may determine population dynamics, fermentative activity and by-product formation.


Assuntos
Fermentação , Hanseniaspora/metabolismo , Saccharomyces cerevisiae/metabolismo , Vinho , Técnicas de Cocultura , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Genômica , Interações Microbianas , Saccharomyces cerevisiae/genética
7.
BBA Adv ; 5: 100112, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38235374

RESUMO

Dye-decolorizing peroxidases (DyPs) are heme-containing enzymes that are structurally unrelated to other peroxidases. Some DyPs show high potential for applications in biotechnology, which critically depends on the stability and redox potential (E°') of the enzyme. Here we provide a comparative analysis of UV-Vis- and surface-enhanced resonance Raman-based spectroelectrochemical methods for determination of the E°' of DyPs from two different organisms, and their variants generated targeting E°' upshift. We show that substituting the highly conserved Arginine in the distal side of the heme pocket by hydrophobic amino acid residues impacts the heme architecture and redox potential of DyPs from the two organisms in a very distinct manner. We demonstrate the advantages and drawbacks of the used spectroelectrochemical approaches, which is relevant for other heme proteins that contain multiple heme centers or spin populations.

8.
Rev Esp Anestesiol Reanim (Engl Ed) ; 70(5): 247-258, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36940854

RESUMO

INTRODUCTION AND OBJECTIVES: Enhanced Recovery After Surgery (ERAS) is a multimodal strategy designed to optimize postoperative recovery and reduce morbidity, length of hospital stay, and care costs. The aim of this study was to evaluate compliance and clinical outcomes 6 months of implementation of the program in scheduled colorectal surgery in a tertiary hospital. MATERIAL AND METHODS: Data from 209 patients who underwent elective colorectal surgery were analysed. The first 102 patients (pre-ERAS group) who underwent surgery between January and May 2018, before the implementation of the program, were compared with the 107 patients treated between May and October 2019, after ERAS implementation. The main outcomes were patient education and counselling, use of intravenous fluids, early mobilization, incidence of postoperative nausea and vomiting, return of bowel function, length of stay, complications, mortality, and overall compliance. RESULTS: The ERAS program was associated with a significant increase in patient education and counselling (p<0.001) and with a significant reduction in intra- and postoperative IV fluid administration (p=0.007 and p<0.001, respectively) and postoperative nausea or vomiting (17.6% vs 5.0%, p=0.007). Time to recovery of activities of daily living (5.29 vs 2.85 days; p<0.001), time to solid oral intake (6.21 vs 4.35 days; p<0.001), time to first flatus (2.41 vs 1.51 days; p<0.001) and defecation (3.35 vs 1.66 days; p<0.001) decreased with ERAS. There were no statistically significant differences in length of stay, complications, and mortality. CONCLUSION: This study showed that the ERAS program improved perioperative outcomes and postoperative recovery in patients undergoing colorectal surgery in our hospital.


Assuntos
Cirurgia Colorretal , Recuperação Pós-Cirúrgica Melhorada , Humanos , Centros de Atenção Terciária , Atividades Cotidianas , Portugal/epidemiologia
9.
Nutrients ; 15(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068741

RESUMO

In PKU, the protein requirements are contentious. In 2018, we evaluated the protein intake in patients with PKU. Ninety-nine early treated patients aged 19.3 ± 8.2 years (54% males) were studied. A total of 24 had hyperphenylalaninemia (HPA), 48 mild and 27 classical PKU. All had an annual nutritional status evaluation. A total of 83% were on diet therapy only, and 17% were on diet with tetrahydrobiopterin therapy. Anthropometry, metabolic control and nutritional intake [total protein (TP, g/kg), natural protein (NP, g/kg), protein equivalent from protein substitutes (PE, g/kg)] were collected. TP adequacy (TPA) was calculated as a % of WHO (2007) safe levels of protein intake. Results were compared with the European PKU Guidelines (EPG). The median % contribution NP of TP intake was 53% [31-100]. Most patients (78%) had a TP intake above the EPG recommendations. The median TPA was 171% [146-203], with 79% [51-165] from NP and 84% [0-109] from PE. A TPA of 100-140% was observed in 16 (16%) patients. Only n = 6 (6%) patients had a TPA < 100%. These results emphasize the heterogeneity of PKU. More research is needed to understand the necessity of a single protein recommendation for all, as a 'one-size-fits-all' solution might not be appropriate.


Assuntos
Fenilalanina , Fenilcetonúrias , Masculino , Humanos , Feminino , Estado Nutricional , Dieta , Antropometria
10.
J Control Release ; 353: 77-95, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410614

RESUMO

Despite being the most prevalent and lethal type of adult brain cancer, glioblastoma (GBM) remains intractable. Promising anti-GBM nanoparticle (NP) systems have been developed to improve the anti-cancer performance of difficult-to-deliver therapeutics, with particular emphasis on tumor targeting strategies. However, current disease modeling toolboxes lack close-to-native in vitro models that emulate GBM microenvironment and bioarchitecture, thus partially hindering translation due to poorly predicted clinical responses. Herein, human GBM heterotypic multicellular tumor microtissues (MCTMs) are generated through high-throughput 3D modeling of U-251 MG tumor cells, tissue differentiated macrophages isolated from peripheral monocytes, and brain microvascular primary endothelial cells. GBM MCTMs mimicked tumor spatial organization, extracellular matrix production and necrosis areas. The bioactivity of a model drug, docetaxel (DTX), and of tumor-targeted DTX-loaded polymeric NPs with a surface L-Histidine moiety (H-NPs), were assessed in the MCTMs. MCTMs cell uptake and anti-proliferative effect was 8- and 3-times higher for H-NPs, respectively, compared to the non-targeted NPs and to free DTX. H-NPs provided a decrease of MCTMs anti-inflammatory M2-macrophages, while increasing their pro-inflammatory M1 counterparts. Moreover, H-NPs showed a particular biomolecular signature through reduced secretion of an array of medium cytokines (IFN-γ, IL-1ß, IL-1Ra, IL-6, IL-8, TGF-ß). Overall, MCTMs provide an in vitro biomimetic model to recapitulate key cellular and structural features of GBM and improve in vivo drug response predictability, fostering future clinical translation of anti-GBM nano-therapeutic strategies.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Células Endoteliais , Linhagem Celular Tumoral , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Citocinas , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Microambiente Tumoral
11.
Microorganisms ; 10(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35056556

RESUMO

The use of yeast starter cultures consisting of a blend of Saccharomyces cerevisiae and non-Saccharomyces yeasts has increased in recent years as a mean to address consumers' demands for diversified wines. However, this strategy is currently limited by the lack of a comprehensive knowledge regarding the factors that determine the balance between the yeast-yeast interactions and their responses triggered in complex environments. Our previous studies demonstrated that the strain Hanseniaspora guilliermondii UTAD222 has potential to be used as an adjunct of S. cerevisiae in the wine industry due to its positive impact on the fruity and floral character of wines. To rationalize the use of this yeast consortium, this study aims to understand the influence of production factors such as sugar and nitrogen levels, fermentation temperature, and the level of co-inoculation of H. guilliermondii UTAD222 in shaping fermentation and wine composition. For that purpose, a Central Composite experimental Design was applied to investigate the combined effects of the four factors on fermentation parameters and metabolites produced. The patterns of variation of the response variables were analyzed using machine learning methods, to describe their clustered behavior and model the evolution of each cluster depending on the experimental conditions. The innovative data analysis methodology adopted goes beyond the traditional univariate approach, being able to incorporate the modularity, heterogeneity, and hierarchy inherent to metabolic systems. In this line, this study provides preliminary data and insights, enabling the development of innovative strategies to increase the aromatic and fermentative potential of H. guilliermondii UTAD222 by modulating temperature and the availability of nitrogen and/or sugars in the medium. Furthermore, the strategy followed gathered knowledge to guide the rational development of mixed blends that can be used to obtain a particular wine style, as a function of fermentation conditions.

12.
Cancer Res ; 82(7): 1423-1434, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35131872

RESUMO

Ovarian cancer is the deadliest gynecologic cancer, and novel therapeutic options are crucial to improve overall survival. Here we provide evidence that impairment of oxidative phosphorylation (OXPHOS) can help control ovarian cancer progression, and this benefit correlates with expression of the two mitochondrial master regulators PGC1α and PGC1ß. In orthotopic patient-derived ovarian cancer xenografts (OC-PDX), concomitant high expression of PGC1α and PGC1ß (PGC1α/ß) fostered a unique transcriptional signature, leading to increased mitochondrial abundance, enhanced tricarboxylic acid cycling, and elevated cellular respiration that ultimately conferred vulnerability to OXPHOS inhibition. Treatment with the respiratory chain complex I inhibitor IACS-010759 caused mitochondrial swelling and ATP depletion that consequently delayed malignant progression and prolonged the lifespan of high PGC1α/ß-expressing OC-PDX-bearing mice. Conversely, low PGC1α/ß OC-PDXs were not affected by IACS-010759, thus pinpointing a selective antitumor effect of OXPHOS inhibition. The clinical relevance of these findings was substantiated by analysis of ovarian cancer patient datasets, which showed that 25% of all cases displayed high PGC1α/ß expression along with an activated mitochondrial gene program. This study endorses the use of OXPHOS inhibitors to manage ovarian cancer and identifies the high expression of both PGC1α and ß as biomarkers to refine the selection of patients likely to benefit most from this therapy. SIGNIFICANCE: OXPHOS inhibition in ovarian cancer can exploit the metabolic vulnerabilities conferred by high PGC1α/ß expression and offers an effective approach to manage patients on the basis of PGC1α/ß expression.


Assuntos
Neoplasias Ovarianas , Fosforilação Oxidativa , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas de Ligação a RNA , Animais , Feminino , Humanos , Camundongos , Mitocôndrias/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Oxirredução , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteínas de Ligação a RNA/metabolismo
13.
Nutrients ; 13(9)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34578995

RESUMO

Blood phenylalanine (Phe) is used as the primary marker to evaluate metabolic control. Our study aimed to describe the metabolic control of patients with phenylketonuria (PKU) comparing three different treatment recommendations (European guidelines/US guidelines/Portuguese consensus). This was a retrospective, observational, single centre study in patients with PKU collecting data on blood Phe levels from 2017. Nutritional intake data and sapropterin (BH4) prescription were collected at the last appointment of 2017. The final sample studied included 87 patients (48% females) [13 hyperphenylalaninemia; 47 mild PKU; 27 classical PKU] with a median age of 18 y (range: 1-36 y). The median number of blood Phe measurements for patients was 21 (range: 6-89). In patients aged < 12 y, the median blood Phe level was 300 µmol/L (range 168-480) and 474 µmol/L (range 156-1194) for patients ≥ 12 y. Overall, a median of 83% of blood Phe levels were within the European PKU guidelines target range. In patients aged ≥ 12 years, there was a higher median % of blood Phe levels within the European PKU guidelines target range (≥12 y: 84% vs. <12 y: 56%). In children < 12 y with classical PKU (n = 2), only 34% of blood Phe levels were within target range for all 3 guidelines and 49% with mild PKU (n = 11). Girls had better control than boys (89% vs. 66% median Phe levels within European Guidelines). Although it is clear that 50% or more patients were unable to achieve acceptable metabolic control on current treatment options, a globally agreed upper Phe target associated with optimal outcomes for age groups is necessary. More studies need to examine how clinics with dissimilar resources, different therapeutic Phe targets and frequency of monitoring relate to metabolic control.


Assuntos
Biopterinas/análogos & derivados , Dieta com Restrição de Proteínas/métodos , Fenilalanina/sangue , Fenilcetonúrias/sangue , Fenilcetonúrias/terapia , Adolescente , Adulto , Biomarcadores/sangue , Biopterinas/uso terapêutico , Criança , Pré-Escolar , Ingestão de Alimentos , Feminino , Humanos , Lactente , Masculino , Portugal , Guias de Prática Clínica como Assunto , Padrões de Referência , Valores de Referência , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
14.
Orphanet J Rare Dis ; 16(1): 84, 2021 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-33581730

RESUMO

BACKGROUND: In phenylketonuria (PKU), modified casein glycomacropeptide supplements (CGMP-AA) are used as an alternative to the traditional phenylalanine (Phe)-free L-amino acid supplements (L-AA). However, studies focusing on the long-term nutritional status of CGMP-AA are lacking. This retrospective study evaluated the long-term impact of CGMP-AA over a mean of 29 months in 11 patients with a mean age at CGMP-AA onset of 28 years (range 15-43) [8 females; 2 hyperphenylalaninaemia (HPA), 3 mild PKU, 3 classical PKU and 3 late-diagnosed]. Outcome measures included metabolic control, anthropometry, body composition and biochemical parameters. RESULTS: CGMP-AA, providing 66% of protein equivalent intake from protein substitute, was associated with no significant change in blood Phe with CGMP-AA compared with baseline (562 ± 289 µmol/L vs 628 ± 317 µmol/L; p = 0.065). In contrast, blood tyrosine significantly increased on CGMP-AA (52.0 ± 19.2 µmol/L vs 61.4 ± 23.8 µmol/L; p = 0.027). CONCLUSIONS: Biochemical nutritional markers remained unchanged which is an encouraging finding in adults with PKU, many of whom are unable to maintain full adherence with nutritionally fortified protein substitutes. Longitudinal, prospective studies with larger sample sizes are necessary to fully understand the metabolic impact of using CGMP-AA in PKU.


Assuntos
Caseínas , Fenilcetonúrias , Adolescente , Adulto , Caseínas/uso terapêutico , Feminino , Humanos , Masculino , Fragmentos de Peptídeos , Fenilcetonúrias/tratamento farmacológico , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
15.
Appl Environ Microbiol ; 76(24): 7918-24, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20952643

RESUMO

Throughout alcoholic fermentation, nitrogen depletion is one of the most important environmental stresses that can negatively affect the yeast metabolic activity and ultimately leads to fermentation arrest. Thus, the identification of the underlying effects and biomarkers of nitrogen limitation is valuable for controlling, and therefore optimizing, alcoholic fermentation. In this study, reactive oxygen species (ROS), plasma membrane integrity, and cell cycle were evaluated in a wine strain of Saccharomyces cerevisiae during alcoholic fermentation in nitrogen-limiting medium under anaerobic conditions. The results indicated that nitrogen limitation leads to an increase in ROS and that the superoxide anion is a minor component of the ROS, but there is increased activity of both Sod2p and Cta1p. Associated with these effects was a decrease in plasma membrane integrity and a persistent cell cycle arrest at G(0)/G(1) phases. Moreover, under these conditions it appears that autophagy, evaluated by ATG8 expression, is induced, suggesting that this mechanism is essential for cell survival but does not prevent the cell cycle arrest observed in slow fermentation. Conversely, nitrogen refeeding allowed cells to reenter cell cycle by decreasing ROS generation and autophagy. Altogether, the results provide new insights on the understanding of wine fermentations under nitrogen-limiting conditions and further indicate that ROS accumulation, evaluated by the MitoTracker Red dye CM-H(2)XRos, and plasma membrane integrity could be useful as predictive markers of fermentation problems.


Assuntos
Álcoois/metabolismo , Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Superóxidos/análise , Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Meios de Cultura/química , Fermentação , Viabilidade Microbiana/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia
16.
J Microbiol Biotechnol ; 20(9): 1314-21, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20890097

RESUMO

Sulfur metabolism in S. cerevisiae is well established, but the mechanisms underlying the formation of sulfide remain obscure. Here we investigated by real time RT-PCR the dependence of expression levels of MET3, MET5/ECM17, MET10, MET16 and MET17 along with SSU1 on nitrogen availability in two wine yeast strains that produce divergent sulfide profiles. MET3 was the most highly expressed of the genes studied in strain PYCC4072, and SSU1 in strain UCD522. Strains behaved differently according to the sampling times, with UCD522 and PYCC4072 showing the highest expression levels at 120h and 72h, respectively. In the presence of 267mg assimilable N/l, the genes were more highly expressed in strain UCD522 than in PYCC4072. MET5/ECM17 and MET17 were only weakly expressed in both strains under any condition tested. MET10 and SSU1 in both strains, but MET16 only in PYCC4072, were consistently up-regulated when sulfide production was inhibited. This study illustrates that strain genotype could be important in determining enzyme activities and therefore the rate of sulfide liberation. This linkage, for some yeast strains, of sulfide production to expression levels of genes associated to sulfate assimilation and sulfur amino acid biosynthesis could be relevant for defining new strategies for genetic improvement of wine yeasts.


Assuntos
Regulação Fúngica da Expressão Gênica , Nitrogênio/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sulfetos/metabolismo , Vinho/microbiologia , Proteínas de Transporte de Ânions/metabolismo , Fermentação , Genes Fúngicos , Sulfeto de Hidrogênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Sulfato Adenililtransferase/metabolismo
17.
Biosens Bioelectron ; 153: 112055, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32056659

RESUMO

Immobilized dye-decolorizing peroxidase from Pseudomonas putida MET94 (PpDyP) and three variants generated by directed evolution (DE) are studied aiming at the design of a biosensor for H2O2 detection. Structural properties of the enzymes in solution and immobilized state are addressed by resonance Raman (RR) and surface enhanced RR (SERR) spectroscopy, and the electrocatalytic properties are analyzed by electrochemistry. The wild-type (wt) and 29E4 variant (with E188K and H125Y mutations) represent excellent candidates for development of H2O2 biosensors, since they exhibit a good dynamic response range (1-200 µM H2O2), short response times (2 s) and a superior sensitivity (1.3-1.4 A⋅M-1⋅cm-2) for H2O2, as well as selectivity and long term stability. In contrast to the solution state, 6E10 (with E188K, A142V and H125Y mutations) and 25F6 (with E188K, A142V, H125Y and G129D mutations) variants display much lower activity and are inhibited by high concentrations of H2O2 upon adsorption on an electrode. In terms of sensitivity, the bioelectrodes employing wt PpDyP and 29E4 variant outperform HRP based counterparts reported in the literature by 1-4 orders of magnitude. We propose the development of wt or 29E4 PpDyP based biosensor as a valuable alternative to devices that rely on peroxidases.


Assuntos
Técnicas Biossensoriais , Enzimas Imobilizadas/química , Peróxido de Hidrogênio/isolamento & purificação , Peroxidase/química , Corantes/química , Peróxido de Hidrogênio/química , Pseudomonas putida/enzimologia
18.
J Ind Microbiol Biotechnol ; 36(4): 571-83, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19190948

RESUMO

The aim of this study was to evaluate the combined effect of initial nitrogen content on the production of hydrogen sulphide and other volatile compounds during alcoholic fermentation. For that propose, three commercial wine strains of Saccharomyces cerevisiae were used to ferment synthetic grape juice media under different nitrogen concentrations. H(2)S was measured throughout fermentations and other aroma compounds were analyzed at the end of the experiments. The trigger levels at which an inverse relationship between the initial nitrogen present in media and total H(2)S production varied among the three strains tested. For UCD522 and PYCC4072, the highest H(2)S levels were produced in media with 267 mg N l(-1) of initial nitrogen, whereas the lowest levels were detected with nitrogen limitation/starvation conditions (66 mg N l(-1)). Moreover, 21 other aroma compounds belonging to different chemical classes were identified and quantified by solid phase micro-extraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The initial nitrogen concentration more than yeast strain had a decisive effect on the final aroma composition, suggesting that modulation of nutrients emerges as a useful tool for producing desired flavour and odour compounds.


Assuntos
Meios de Cultura/química , Sulfeto de Hidrogênio/metabolismo , Nitrogênio/metabolismo , Compostos Orgânicos/metabolismo , Saccharomyces cerevisiae/metabolismo , Vinho/microbiologia , Meios de Cultura/metabolismo , Fermentação , Compostos Orgânicos/química , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/isolamento & purificação , Volatilização , Vinho/análise
19.
Work ; 64(2): 217-227, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31524191

RESUMO

BACKGROUND: Small and medium-sized enterprises (SMEs) face greatest difficulty in managing occupational risks compared to large enterprises. Limited resources, little knowledge about risk management process and deficiencies in organizational processes are often pointed in the literature as important obstacles to occupational safety and health (OSH) performance in SMEs. However, external factors can also be of paramount importance, such as the economic crisis. Because under specific scenarios OSH conditions may deteriorate in SMEs, is important to establish effective indicators. OBJECTIVE: This study aims to identify OSH performance indicators within the context of SMEs. METHODS: To identify the indicators, a literature review was carried out on different studies published in scientific journals in the OSH field between 2008 and October 2018 using the Scopus, ScienceDirect, Web of Science and PubMed databases. RESULTS: As a result, 14 management and organization OSH indicators applied to SMEs were identified, along with 5 at individual OSH indicators. CONCLUSION: The indicators were discussed in relation to its applicability to assess OSH performance, as well as their reliability. Future research should be done to assess the identified indicators in SMEs.


Assuntos
Saúde Ocupacional/normas , Indicadores de Qualidade em Assistência à Saúde/tendências , Empresa de Pequeno Porte/normas , Humanos , Gestão de Riscos/métodos , Gestão da Segurança/métodos , Empresa de Pequeno Porte/métodos
20.
Food Sci Nutr ; 7(2): 617-627, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30847141

RESUMO

The aim of this study was the production of blueberry wine and the characterization of the volatile compounds of fermented and aging in bottle products. Multivariate data analysis indicated similarity of volatile compounds released when fermentations were conducted at laboratory-scale and midscale, with the exception of one replicate creating a distinctive group characterized by low concentrations of acetaldehyde, methanol, 1-hexanol, and ethyl hexanoate, and the production of polyalcohols such as 2,3-butanediols. This experiment was the only one where no adjustments of YAN were performed. Some of the major volatile compounds (acetaldehyde, ethyl acetate, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-phenylethanol) were found above their perception thresholds. Esters and terpenic compounds were the groups of volatiles expressed the most in blueberry wines, followed by volatile fatty acids, alcohols, and norisoprenoids (3-hydroxy-7,8-dihydro-ß-ionone, 3-oxo-α-ionol, and 3-hydroxy-7,8-dihydro-ß-ionol). The wines that experienced bottle-aging are characterized by high concentrations of ethyl esters, diethyl succinate, ethyl lactate, and diethyl malonate. The results contribute for deeper knowledge of the technological procedure, analytical characteristics, and volatile compounds of blueberry wines, reinforcing the interest in this beverage and opening perspectives for further studies on the production of new blueberry-based products with differential characteristics that value its nutraceutical and functional properties.

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