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1.
PLoS One ; 16(3): e0248029, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33788866

RESUMEN

Many countries have seen a two-wave pattern in reported cases of coronavirus disease-19 during the 2020 pandemic, with a first wave during spring followed by the current second wave in late summer and autumn. Empirical data show that the characteristics of the effects of the virus do vary between the two periods. Differences in age range and severity of the disease have been reported, although the comparative characteristics of the two waves still remain largely unknown. Those characteristics are compared in this study using data from two equal periods of 3 and a half months. The first period, between 15th March and 30th June, corresponding to the entire first wave, and the second, between 1st July and 15th October, corresponding to part of the second wave, still present at the time of writing this article. Two hundred and four patients were hospitalized during the first period, and 264 during the second period. Patients in the second wave were younger and the duration of hospitalization and case fatality rate were lower than those in the first wave. In the second wave, there were more children, and pregnant and post-partum women. The most frequent signs and symptoms in both waves were fever, dyspnea, pneumonia, and cough, and the most relevant comorbidities were cardiovascular diseases, type 2 diabetes mellitus, and chronic neurological diseases. Patients from the second wave more frequently presented renal and gastrointestinal symptoms, were more often treated with non-invasive mechanical ventilation and corticoids, and less often with invasive mechanical ventilation, conventional oxygen therapy and anticoagulants. Several differences in mortality risk factors were also observed. These results might help to understand the characteristics of the second wave and the behaviour and danger of SARS-CoV-2 in the Mediterranean area and in Western Europe. Further studies are needed to confirm our findings.


Asunto(s)
COVID-19/epidemiología , COVID-19/terapia , Hospitalización/estadística & datos numéricos , Anciano , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , España/epidemiología , Resultado del Tratamiento
2.
PLoS One ; 11(4): e0154601, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27123846

RESUMEN

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) causes a wide spectrum of liver damage, ranging from simple steatosis to cirrhosis. However, simple steatosis (SS) and steatohepatitis (NASH) cannot yet be distinguished by clinical or laboratory features. The aim of this study was to assess the relationship between alpha-ketoglutarate and the degrees of NAFLD in morbidly obese patients. MATERIALS AND METHODS: We used a gas chromatography-quadruple time-of-flight-mass spectrometry analysis to quantify alpha-ketoglutarate in serum from normal-weight subjects (n = 30) and morbidly obese women (n = 97) with or without NAFLD. RESULTS: We found that serum levels of alpha-ketoglutarate were significantly higher in morbidly obese women than in normal-weight women. We showed that circulating levels of alpha-ketoglutarate were lower in lean controls and morbidly obese patients without NAFLD. We also found that alpha-ketoglutarate serum levels were higher in both SS and NASH than in normal liver of morbidly obese patients. However, there was no difference between SS and NASH. Moreover, we observed that circulating levels of alpha-ketoglutarate were associated with glucose metabolism parameters, lipid profile, hepatic enzymes and steatosis degree. In addition, diagnostic performance of alpha-ketoglutarate has been analyzed in NAFLD patients. The AUROC curves from patients with liver steatosis exhibited an acceptable clinical utility. Finally, we showed that the combination of biomarkers (AST, ALT and alpha-ketoglutarate) had the highest accuracy in diagnosing liver steatosis. CONCLUSION: These findings suggest that alpha-ketoglutarate can determine the presence of non-alcoholic fatty liver in morbidly obese patients but it is not valid a biomarker for NASH.


Asunto(s)
Ácidos Cetoglutáricos/sangre , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Obesidad Mórbida/sangre , Adulto , Biomarcadores/sangre , Femenino , Humanos , Hígado/patología , Pruebas de Función Hepática
3.
Bioresour Technol ; 112: 341-4, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22440576

RESUMEN

A new biotechnological procedure using laccase in combination with a hydrophobic phenolic compound (lauryl gallate) for the hydrophobization of cellulose fibres and internal sizing of paper was developed. Cellulose fibres from hardwood kraft pulp were incubated with laccase (Lac), in combination with lauryl gallate (LG). The Lac-LG treatment resulted in the internal sizing of paper, and also in significantly reduced water penetration in the handsheets and wettability of the paper surface. Paper was found not to be effectively rendered hydrophobic by LG alone. SEM images of the fibre network revealed the presence of the sizing agent: a product of the reaction between laccase and lauryl gallate. Binding of lauryl gallate to cellulose fibres was suggested by the increase in kappa number of the pulp and further confirmed by IR spectroscopy.


Asunto(s)
Biotecnología/métodos , Celulosa/metabolismo , Ácido Gálico/análogos & derivados , Interacciones Hidrofóbicas e Hidrofílicas/efectos de los fármacos , Lacasa/metabolismo , Fenoles/farmacología , Acetona/química , Ácido Gálico/farmacología , Permeabilidad/efectos de los fármacos , Factores de Tiempo , Trametes/enzimología
4.
Bioresour Technol ; 102(4): 3911-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21194930

RESUMEN

Flax soda/AQ pulps were treated with different fungal laccase-mediator combinations followed by physical and chemical characterization of the pulps to obtain a thorough understanding of the laccase/mediator effects on hexenuronic acid (HexA) removal and the coupling of mediator onto pulps for fiber functionalization. Large differences were found and the presence of lauryl gallate (LG) during Trametes villosa laccase (TvL) treatment (TvL+LG) resulted in a much larger reduction of pulp-linked HexA than the combination of p-coumaric acid (PCA) and Pycnoporus cinnabarinus laccase (PcL). A major portion of LG became attached to the pulp as revealed by an increase in the kappa number and further confirmed by thioacidolysis and (1)H NMR analysis of solubilized pulp fractions. Additional experiments with other chemical pulps and isolated pulp xylan and lignin revealed that HexA seems to be the sole pulp component attacked by TvL+LG. As a substrate for TvL, the reaction preference order is PCA>HexA>LG.


Asunto(s)
Biotecnología/métodos , Ácidos Hexurónicos/química , Lacasa/química , Acetona/química , Ácidos Cumáricos/química , Lino/química , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Lignina/química , Espectroscopía de Resonancia Magnética/métodos , Modelos Químicos , Propionatos , Pycnoporus/enzimología , Compuestos de Sulfhidrilo/química , Trametes/enzimología , Xilanos/química
5.
Bioresour Technol ; 102(3): 2799-803, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21050744

RESUMEN

The aim of this work was to develop an innovative method for the internal sizing of paper by use of laccase and hydrophobic compounds. Nine different products containing hydrophobic moieties were tested in combination with laccase derived from Trametes villosa on Eucalyptus globulus kraft pulp in order to assess their internal sizing capability. The strongest internal sizing effect was obtained with lauryl gallate (LG). Heat treatment of the handsheets was found to increase the resistance to water absorption of internally sized samples significantly. Tests were conducted under variable operating conditions, including enzyme and reactant doses and treatment time. In addition to altering the water absorption rate, internal sizing with the laccase-LG treatments was found to affect the mechanical and optical properties of the handsheets. As shown in this work, treatments based on laccase and a hydrophobic compound (particularly lauryl gallate), can provide a new, effective biotechnological method for the internal sizing of paper.


Asunto(s)
Celulosa/química , Eucalyptus/enzimología , Lacasa/química , Papel , Trametes/enzimología , Absorción , Interacciones Hidrofóbicas e Hidrofílicas
6.
Bioresour Technol ; 101(11): 4104-10, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20138756

RESUMEN

The phenols syringaldehyde (SA), acetosyringone (AS) and p-coumaric acid (PCA) were used as natural laccase mediators in combination with a laccase from Pycnoporus cinnabarinus to bleach flax fibres. Their performance was compared with 1-hydroxybenzotriazole (HBT) in terms of enzyme stability, and pulp and effluent properties. HBT and PCA were found to inactivate laccase in the absence of pulp. However, in the presence of unbleached flax pulp stability was increased; for example with PCA, laccase retained 77% of its initial activity, in contrast with complete inactivation in the absence of pulp. This suggests a protective effect of the pulp against denaturalization of the enzyme. All natural mediators resulted in a reduced kappa number after the subsequent alkaline treatment with hydrogen peroxide; the reduction being especially marked with SA (about 2 units - with respect to the control sample) and comparable to that obtained by HBT. Brightness was significantly increased by all natural mediators, but especially by AS and SA (23% with both), which performed very similarly to HBT in this respect. Natural mediators therefore might constitute an effective alternative to synthetic mediators for flax pulp biobleaching. This paper demonstrates for the first time the use of natural mediators in the laccase-assisted delignification of flax pulp and their effect on the properties of the resulting effluents.


Asunto(s)
Color , Lino , Lacasa/metabolismo , Acetofenonas/metabolismo , Basidiomycota/enzimología , Benzaldehídos/metabolismo , Ácidos Cumáricos/metabolismo , Estabilidad de Enzimas , Propionatos , Temperatura
7.
Bioresour Technol ; 100(23): 5911-6, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19574042

RESUMEN

The effects of laccase-natural mediator systems (LMS) on sisal pulp and their potential for either biobleaching or functionalizing (via radical-coupling) its fibres were investigated. The enzyme treatment (L stage) was followed by extraction with hydrogen peroxide in order to determine whether observable effects could be enhanced by removing LMS-modified lignin. Four different plant phenols [viz. the p-hydroxycinnamic compounds sinapic acid (SNC), ferulic acid (FRC), coniferyl aldehyde (CLD) and sinapyl aldehyde (SLD)] were used as laccase redox mediators and their effects on pulp and effluents compared with those of the synthetic compound 1-hydroxybenzotriazole (HBT). During the L stage performed with HBT, laccase underwent a loss of 99% and 78% of the initial activity, in the absence and presence of pulp, respectively. With natural mediators inactivation was markedly reduced, being the residual activity between 65% and 100% of the initial one, in the presence of pulp. The pulp was found to protect the enzyme against inactivation: the activity was only reduced by 45% in its presence. Under the operating conditions used the natural mediators proved less efficient than HBT in facilitating pulp bleaching; rather, they tended to bind to pulp fibres. This effect could be used to functionalize fibres in order to improve intrinsic properties of pulp or introducing novel ones (e.g. antimicrobial, antioxidant, optical properties, etc.). This paper shows for the first time the application of laccase-mediator systems to sisal pulp.


Asunto(s)
Biotecnología/métodos , Lacasa/química , Madera/metabolismo , Acroleína/análogos & derivados , Aldehídos/química , Aniones , Ácidos Cumáricos/química , Peróxido de Hidrógeno/química , Lignina/química , Oxidación-Reducción , Oxígeno/química , Papel , Fenol/química , Árboles/química
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