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4.
Photochem Photobiol Sci ; 22(3): 641-654, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36401770

RESUMEN

Today, the emergence of increasingly restrictive treatment and reuse policies make the implementation of full-scale tertiary treatment, capable of improving the quality of water, a priority. Full-scale TiO2 photocatalysis systems are resulting in a promising option, since TiO2 is commercially available. However, questions such as how to work continuously during day/night irradiation cycle, or the removing of TiO2 in outlet flow are still unresolved. In this work, a full-scale system integrating a solar CPC/UV-LED step combined with commercial microfiltration membranes was installed in a conventional WWTP for agricultural reuse purposes. After optimization, 0.5 g/L of catalyst and combined SOLAR + UV-LED showing the highest pharmaceutical removal percentages, while a self-designed UV-LED included in the own reaction tank resulting in higher efficiencies compared with commercial lamps. Longer membrane surface area decreased fouling problems in the system. However, 60 min of irradiation time was necessary to reach the most restrictive water quality values according with (EU 2020/741). After optimization step, total costs were reduced by 45%. However, it was shown that a reduction in operating and maintenance costs, along with the development of more effective and economical commercial filtration membranes is a key factor; therefore, working on these aspects is essential in the treated water cost reduction.

6.
Neurologia (Engl Ed) ; 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36347422

RESUMEN

INTRODUCTION: There is an extending use of percutaneous closure of patent foramen ovale (PFO) as therapy for PFO-associated cryptogenic strokes. The aim of our study was to investigate the clinical practice of percutaneous closure of PFO and to analyse the variables for decision-making on the selection of patients for this procedure. METHOD: A prospective observational multicentric survey was conducted using all the cases of cryptogenic stroke/transient ischaemic attack associated with PFO recorded in the NORDICTUS hospital registry during the period 2018-2021. Clinical data, radiological patterns, echocardiogram data and factors related to PFO-associated stroke (thromboembolic disease and paradoxical embolism criteria) were recorded. The indication for closure was analysed according to age (≤/> 60 years) and the characteristics of the PFO. RESULTS: In the group ≤ 60 years (n = 488), 143 patients (29.3%) underwent PFO closure. The most influential variables for this therapy were detection of a high-risk PFO (OR 4.11; IC 2.6-6.5, P < .001), criteria for paradoxical embolism (OR 2.61; IC 1.28-5.28; P = .008) and previous use of antithrombotics (OR 2.67; IC 1.38-5.18; P = .009). In the > 60 years group (n = 124), 24 patients had PFO closure (19%). The variables related to this option were history of pulmonary thromboembolism, predisposition to thromboembolic disease, paradoxical embolism criteria, and high-risk PFO. CONCLUSIONS: The detection of a high-risk PFO (large shunt, shunt with associated aneurysm) is the main criterion for a percutaneous closure-based therapy. Other conditions to consider in the eligibility of patients are the history of thromboembolic disease, paradoxical embolism criteria or the previous use of antithrombotics.

7.
J Environ Manage ; 324: 116321, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36179471

RESUMEN

The use of reclaimed water to irrigate agricultural crops has increased in recent years as a consequence of water shortage constituting a potential risk for human health. The main objective of this study was to evaluate the impact on the soil-plant system and determining the accumulation of carbamazepine (CBZ), diclofenac (DCF), ketoprofen (KTP) and naproxen (NPX) in the edible part of lettuce under commonly used agricultural practices in commercial production. For this purpose, red oak baby lettuce (Lactuca sativa L.) was irrigated with reclaimed water fortified with different concentrations of pharmaceuticals. The study was carried out in two different scenarios: soil and tray. The tray experiments were conducted with substrate and took place at three different seasons of the year. Lettuce tissue sampled from these experiments were analysed 3 times during the lettuce growing cycle (first, second and third harvest). The practices of first harvest regrowth were also evaluated. For all experiments, CBZ showed the highest accumulation in lettuce leaves of the pharmaceuticals tested, showing a correlation between irrigation exposure time and pharmaceutical uptake. Unexpectedly, DCF was the compound with the highest uptake levels after regrowth practices. Results suggested that pharmaceuticals uptake could be directly associated with the irrigation method and possible accumulation in soil and substrates, while concentration of pharmaceuticals in substrates were 10 times higher. Based on the concentration values detected in lettuce leaves, the risk assessment suggests that no compounds imply any risk to human health, except CBZ for those on vegetarian diets in the tray scenario. Although commercial agricultural practices are usually not considered with regards to risk reduction, in this experiment we demonstrated that climatic conditions are a key factor in pharmaceuticals uptake and different agricultural practices (soil cropping and drip irrigation) can limit the presence of pharmaceutical compounds in crops.


Asunto(s)
Lactuca , Contaminantes Químicos del Agua , Humanos , Lactuca/química , Riego Agrícola/métodos , Agua/análisis , Contaminantes Químicos del Agua/análisis , Aguas Residuales/química , Carbamazepina , Productos Agrícolas , Suelo/química , Medición de Riesgo , Diclofenaco , Preparaciones Farmacéuticas
8.
Comput Struct Biotechnol J ; 20: 3080-3095, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35782727

RESUMEN

Dendroctonus bark beetles are the most destructive agents in coniferous forests. These beetles come into contact with the toxic compounds of their host's chemical defenses throughout their life cycle, some of which are also used by the insects as kairomones to select their host trees during the colonization process. However, little is known about the molecular mechanisms by which the insects counteract the toxicity of these compounds. Here, two sibling species of bark beetles, D. valens and D. rhizophagus, were stimulated with vapors of a blend of their main kairomones (α-pinene, ß-pinene and 3-carene), in order to compare the transcriptional response of their gut. A total of 48 180 unigenes were identified in D. valens and 43 704 in D. rhizophagus, in response to kairomones blend. The analysis of differential gene expression showed a transcriptional response in D. valens (739 unigenes, 0.58-10.36 Log2FC) related to digestive process and in D. rhizophagus (322 unigenes 0.87-13.08 Log2FC) related to xenobiotics metabolism. The expression profiles of detoxification genes mainly evidenced the up-regulation of COEs and GSTs in D. valens, and the up-regulation of P450s in D. rhizophagus. Results suggest that terpenes metabolism comes accompanied by an integral hormetic response, result of compensatory mechanisms, including the activation of other metabolic pathways, to ensure the supply of energy and the survival of organisms which is specific for each species, according to its life history and ecological strategy.

11.
Rev. mex. ing. bioméd ; 42(1): e1110, Jan.-Apr. 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1156801

RESUMEN

ABSTRACT A new coronavirus denominated first 2019-nCoV and later SARS-CoV-2 was found in Wuhan, China in December of 2019. This paper compares three mathematical methods: nonlinear regression, SIR, and SEIR epidemic models, to track the covid-19 disease in nine countries affected by the SARS-CoV-2 virus, to help epidemiologists to know the disease trajectory, considering initial data in the pandemic, mainly 100 days from the beginning. To evaluate the results obtained with the three methods one-way ANOVA is applied. The average of predicted infected cases with SARS-CoV-2, obtained with the mentioned methods was: for United States of America 1,098,508, followed by Spain with 226,721, Italy with 202,953, France with 183,897 United Kingdom with 182,190, Germany with 159,407, Canada with 58,696, Mexico with 50,366 and Argentina with 4,860 in average. The one-way ANOVA does not show a significant difference among the results of the projected infected cases by SARS-CoV-2, using nonlinear regression, SIR, and SEIR epidemic methods. The above could mean that initially any method can be used to model the pandemic course.


RESUMEN Un nuevo coronavirus denominado primero 2019-nCoV y más tarde SARS-CoV-2 fue encontrado en Wuhan, China en diciembre de 2019. El objetivo de este trabajo es comparar tres métodos matemáticos: regresión no lineal, modelos epidemiológicos SIR y SEIR, para rastrear la enfermedad del COVID-19 en nueve países infectados por el virus SARS-CoV-2, con el propósito de ayudar al epidemiólogo a conocer el curso de la pandemia, considerando principalmente sus primeros 100 días. Para evaluar los resultados obtenidos de la aplicación de los tres métodos, se aplicó ANOVA de una vía. El número promedio de casos infectados con SARS-CoV-2, obtenidos con los tres métodos descritos son: para Estados Unidos 1,098,508, seguido de España con 226,721, Italia con 202,953, Francia con 183,897 Reino Unido con 182,190, Alemania con 159,407, Canadá con 58,696, México con 50,366 y Argentina con 4,860 en promedio. El ANOVA de una vía no muestra diferencias significativas entre los resultados de los casos infectados proyectados por SARS-CoV-2, utilizando la regresión no lineal y los métodos SIR and SEIR. Lo anterior podría señalar que cualquiera de los tres métodos estudiados puede modelar el curso de la pandemia en las condiciones descritas para cada uno.

12.
Environ Technol ; 42(26): 4047-4056, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32188337

RESUMEN

Models adapt constantly, usually increasing the degree of detail describing physical phenomena. In water resource recovery facilities, models based on mass and/or heat balances have been used to describe and improve operation. While both mass and heat balances have proven their worth individually, the question arises to which extent their coupling, which entails increased model complexity, warrants the supposedly more precise simulation results. In order to answer this question, the need for and effects of coupling mass and heat balances in modelling studies were evaluated in this work for a biological nitrogen removal process treating highly concentrated wastewater. This evaluation consisted on assessing the effect of the coupling of mass and heat balances on the prediction of: (1) nitrogen removal efficiency; (2) temperature; (3) heat recovery. In general, mass balances are sufficient for evaluating nitrogen removal efficiency and effluent nitrogen concentrations. If one desires to evaluate the effect of temperature changes (e.g. daily, weekly, seasonally) on nitrogen removal efficiency, the use of temperature profiles as an input variable to a mass balance-based model is recommended over the coupling of mass and heat balances. In terms of temperature prediction, considering a constant biological heat generation term in the heat balance model provides sufficient information - i.e. without the coupling of mass and heat balances. Also, for evaluating the heat recovery potential of the system, constant biological heat generation values provide valuable information, at least under normal operating conditions, i.e. when the solids retention time is large enough to maintain nitrification.


Asunto(s)
Nitrógeno , Aguas del Alcantarillado , Reactores Biológicos , Desnitrificación , Calor , Eliminación de Residuos Líquidos , Aguas Residuales
13.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-33375157

RESUMEN

Dendroctonus-bark beetles are natural agents contributing to vital processes in coniferous forests, such as regeneration, succession, and material recycling, as they colonize and kill damaged, stressed, or old pine trees. These beetles spend most of their life cycle under stem and roots bark where they breed, develop, and feed on phloem. This tissue is rich in essential nutrients and complex molecules such as starch, cellulose, hemicellulose, and lignin, which apparently are not available for these beetles. We evaluated the digestive capacity of Dendroctonusrhizophagus to hydrolyze starch. Our aim was to identify α-amylases and characterize them both molecularly and biochemically. The findings showed that D. rhizophagus has an α-amylase gene (AmyDr) with a single isoform, and ORF of 1452 bp encoding a 483-amino acid protein (53.15 kDa) with a predicted signal peptide of 16 amino acids. AmyDr has a mutation in the chlorine-binding site, present in other phytophagous insects and in a marine bacterium. Docking analysis showed that AmyDr presents a higher binding affinity to amylopectin compared to amylose, and an affinity binding equally stable to calcium, chlorine, and nitrate ions. AmyDr native protein showed amylolytic activity in the head-pronotum and gut, and its recombinant protein, a polypeptide of ~53 kDa, showed conformational stability, and its activity is maintained both in the presence and absence of chlorine and nitrate ions. The AmyDr gene showed a differential expression significantly higher in the gut than the head-pronotum, indicating that starch hydrolysis occurs mainly in the midgut. An overview of the AmyDr gene expression suggests that the amylolytic activity is regulated through the developmental stages of this bark beetle and associated with starch availability in the host tree.


Asunto(s)
Escarabajos/metabolismo , Tracto Gastrointestinal/metabolismo , Pinus/parasitología , Corteza de la Planta/parasitología , Almidón/metabolismo , alfa-Amilasas/metabolismo , Amilopectina/metabolismo , Amilosa/metabolismo , Animales , Unión Competitiva , Escarabajos/enzimología , Escarabajos/genética , Tracto Gastrointestinal/enzimología , Regulación Enzimológica de la Expresión Génica , Hidrólisis , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Unión Proteica , alfa-Amilasas/genética
14.
Clin Transl Oncol ; 22(2): 201-212, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31981079

RESUMEN

In the last 2 decades, clinical genetics on hereditary colorectal syndromes has shifted from just a molecular characterization of the different syndromes to the estimation of the individual risk of cancer and appropriate risk reduction strategies. In the last years, new specific therapies for some subgroups of patients have emerged as very effective alternatives. At the same time, germline multigene panel testing by next-generation sequencing (NGS) technology has become the new gold standard for molecular genetics.


Asunto(s)
Ensayos Clínicos como Asunto/normas , Neoplasias Colorrectales/prevención & control , Predisposición Genética a la Enfermedad , Mutación , Proteínas de Neoplasias/genética , Guías de Práctica Clínica como Asunto/normas , Neoplasias Colorrectales/genética , Humanos , Oncología Médica , Sociedades Médicas
15.
Front Microbiol ; 10: 2180, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31611850

RESUMEN

Bark beetles from Dendroctonus genus promote ecological succession and nutrient cycling in coniferous forests. However, they can trigger outbreaks leading to important economic losses in the forest industry. Conifers have evolved resistance mechanisms that can be toxic to insects but at the same time, bark beetles are capable of overcoming tree barriers and colonize these habitats. In this sense, symbiont yeasts present in the gut of bark beetles have been suggested to play a role in the detoxification process of tree defensive chemicals. In the present study, genes related to this process were identified and their response to a terpene highly toxic to bark beetles and their symbionts was analyzed in the Cyberlindnera americana yeast. The genome and transcriptome of C. americana (ChDrAdgY46) isolated from the gut of Dendroctonus rhizophagus were presented. Genome analysis identified 5752 protein-coding genes and diverse gene families associated with the detoxification process. The most abundant belonged to the Aldo-Keto Reductase Superfamily, ATP-binding cassette Superfamily, and the Major Facilitator Superfamily transporters. The transcriptome analysis of non-α-pinene stimulated and α-pinene stimulated yeasts showed a significant expression of genes belonging to these families. The activities demonstrated by the genes identified as Aryl-alcohol dehydrogenase and ABC transporter under (+)-α-pinene suggest that they are responsible, that C. americana is a dominant symbiont that resists high amounts of monoterpenes inside the gut of bark beetles.

16.
Protein J ; 38(5): 608, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31236753

RESUMEN

The original publication of this article contained a number of grammatical errors. Unfortunately, an incorrect version of the file that did not include some final language editing was inadvertently published online. The original article has been corrected.

17.
Sci Total Environ ; 687: 567-576, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31216510

RESUMEN

This paper contains a multidisciplinary approach that will contribute to design and properly evaluate a treatment line for complex biorecalcitrant wastewaters. To demonstrate this approach a specific industrial wastewater (cork boiling wastewater, CBW) was used. A treatment line based on a coagulation-flocculation step followed by an Advanced Oxidation Process (AOP) (solar photo-Fenton) and combined with an aerobic biological system was evaluated. Applied microbiological techniques: optical microscopy, plate count, DNA extraction and qPCR, indicated that some communities disappeared after the activated sludge adaptation period to the partially treated wastewater, while communities that did not disappear were damaged: 2-log reduction of total heterotrophic bacteria (THB) and a decrease in DNA concentration from 200 ng/µL to 65 ng/µL were observed. Therefore, chemical and microbiological results obtained along the set of experiments, suggested the inefficiency of the combined treatment option between solar photo-Fenton and advanced aerobic biological systems for CBW. This led to the necessity of applying solar photo-Fenton without combining with biotreatment and with the objective of improving the effluent quality enough for being reused in the own industry. Toxicity tests, based on different organisms (after coagulation-flocculation followed by solar photo-Fenton), showed increase on acute toxicity (from 46% to 71% by respirometric assays) and the development of chronic toxicity (from 21-29% to 83-90% also measured by respirometric assays), made evident the incompatibility of this type of wastewater with a biological treatment even after the application of an AOP.


Asunto(s)
Residuos Industriales/análisis , Eliminación de Residuos Líquidos/métodos , Floculación , Aguas del Alcantarillado , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis
18.
Protein J ; 38(5): 598-607, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31119598

RESUMEN

Human cystatin C (HCC) binds and inhibits all types of cysteine proteases from the papain family, including cathepsins (a group of enzymes that participate in a variety of physiological processes), which are some of its natural targets. The affinities of diverse proteases for HCC, expressed as equilibrium binding constants (Kb), range from 106 to 1014 M-1. Isothermal titration calorimetry (ITC) is one of the most useful techniques to characterize the thermodynamics of molecular associations, making it possible to dissect the binding free energy into its enthalpic and entropic components. This information, together with the structural changes that occur during the different associations, could enable better understanding of the molecular basis of affinity. Notwithstanding the high sensitivity of modern calorimeters, ITC requires protein concentrations in at least the 10-100 µM range to obtain reliable data, and it is known that HCC forms oligomers in this concentration range. We present herein a comparative study of the structural, thermal stability, and oligomerization properties of HCC and its stabilized variant (sHCC) L47C/G69C (which possesses an additional disulfide bridge) as well as their binding thermodynamics to the protease chymopapain, analyzed by ITC. The results show that, because sHCC remains monomeric, it is a better reporter than wild-type HCC to characterize the thermodynamics of binding to cysteine proteases.


Asunto(s)
Cistatina C/química , Cistatina C/metabolismo , Proteasas de Cisteína/metabolismo , Cistatina C/genética , Humanos , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Mutación Puntual , Conformación Proteica , Multimerización de Proteína , Estabilidad Proteica , Termodinámica
19.
RSC Adv ; 9(59): 34559-34566, 2019 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-35529993

RESUMEN

Titanium(iv) bis(ammonium lactate)dihydroxide (TiBALDH) is a commercially available reagent frequently used to synthesize TiO2. Particularly, for the biomimetic synthesis of TiO2, TiBALDH is the preferred precursor because it can be mixed in aqueous solutions with no apparent hydrolysis or condensation reactions. Thus, proteins or other biomolecules can be used as a template in aqueous systems for the synthesis of TiO2 from TiBALDH. Nevertheless, there is evidence that TiBALDH is in equilibrium with TiO2, and even, the principal structure of the complex has been suggested as [Ti4O4(lactate)8]8-. Since that chemical equilibrium depends on the polarity of the solvent, in this work we explored a diversity of media to test the chemical stability of TiBALDH and its equilibrium with TiO2 at room temperature. TiBALDH (2.078 M) contains particles of 18.6 ± 7.3 nm in size, if it is diluted with deionized water, the particles reach a size of 5.2 ± 1.7 nm, which suggest that intermolecular interactions form polymers of titanium lactate complexes reversibly, reaching equilibrium after 10 hours. Typical buffer systems were tested; TiBALDH reacted rapidly only with phosphate groups, even if the source came from DNA. Therefore, phosphate buffer must be avoided in biomineralization TiO2 synthesis. In solutions of TiBALDH at basic pH, condensation reactions are promoted to form a gel containing anatase nanoparticles, but if the solutions are acidic, monodisperse anatase nanoparticles of ∼5 nm were observed. The results show that the commercial reagent TiBALDH contains many species of titanium lactate complexes in equilibrium with TiO2, and it is affected by the concentration, time, pH, and several ions. This peculiar behavior must be taken into account when this precursor is used and it could be useful to develop novel synthesis routes of macrostructures with biomolecules in aqueous systems.

20.
Ecotoxicol Environ Saf ; 166: 123-131, 2018 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-30265875

RESUMEN

In cork industry, the operation of boiling raw cork generates large volumes of wastewater named Cork Boiling Wastewater (CBW). The main characteristics are the low biodegradability and medium to low acute toxicity, resulting in the necessity of designing advanced biological treatments by possible conventional activated sludge adaptation. In order to evaluate the variation of bacterial population along that process, a study based on optical microscopy, plate count, DNA extraction, qPCR and massive sequencing techniques was performed. Results showed a diminution of the total and volatile solids (TSS and VSS), jointly with a decrease in DNA concentration, general bacteria (16 S) and ammonia-oxidizing bacteria (AOB). After a few hours of testing, diverse microbiological species died while others showed a possible adaptation of the biological system, accompained by a dissolved organic carbon (DOC) reduction. In addition, toxicity tests based on activated sludge showed the development of chronic toxicity through the contact time. Combination of classical and advanced microbiological techniques, such as quantitative real time Polymerase Chain Reaction (qPCR) and metagenomics, was essential to predict the variation of species during the experiment and to conclude if effective biological adaptation could be finally attained for the target complex wastewater.


Asunto(s)
Biodegradación Ambiental , Eliminación de Residuos Líquidos/métodos , Bacterias/genética , Bacterias/metabolismo , Metagenómica/métodos , Oxidación-Reducción , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Aguas del Alcantarillado/microbiología , Aguas Residuales/química , Aguas Residuales/microbiología
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