Publications by authors named "Xavier Vila"

Xanthates have long been described as poor RAFT/MADIX agents for styrene polymerization. Through the determination of chain transfer constants to xanthates, this work demonstrated beneficial capto-dative substituent effects for the leaving group of a new series of α-amido trifluoromethyl xanthates, with the best effect observed with trifluoroacetyl group. The previously observed Z-group activation with a -trifluoroethyl group compared to the -ethyl counterpart was quantitatively established with = 2.

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Temporary scaffolds that mimic the extracellular matrix's structure and provide a stable substratum for the natural growth of cells are an innovative trend in the field of tissue engineering. The aim of this study is to obtain and design porous 2D fibroin-based cell matrices by femtosecond laser-induced microstructuring for future applications in muscle tissue engineering. Ultra-fast laser treatment is a non-contact method, which generates controlled porosity-the creation of micro/nanostructures on the surface of the biopolymer that can strongly affect cell behavior, while the control over its surface characteristics has the potential of directing the growth of future muscle tissue in the desired direction.

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The repair of large bone defects remains challenging and often requires graft material due to limited availability of autologous bone. In clinical settings, collagen sponges loaded with excessive amounts of bone morphogenetic protein 2 (rhBMP-2) are occasionally used for the treatment of bone non-unions, increasing the risk of adverse events. Therefore, strategies to reduce rhBMP-2 dosage are desirable.

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Purpose: On March 16, 2020, the Spanish government declared a state of alarm due to the rapid spread of coronavirus disease 2019 (COVID-19). Patients with chronic obstructive pulmonary disease (COPD) were restricted to remain confined at home, and medical visits were cancelled for 3 months. The impact of this lockdown on the manifestations of COPD and the quality-of-life of these patients has not been explored.

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Decellularization of blood vessels is a promising approach to generate native biomaterials for replacement of diseased vessels. The decellularization process affects the mechanical properties of the vascular graft and thus can have a negative impact for in vivo functionality. The aim of this study was to determine how detergents under different fluid dynamics affects decellularization efficacy and mechanical properties of the vascular graft.

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Article Synopsis
  • The study focused on identifying factors that contribute to the failure of asthma treatment step-down in patients with moderate to severe asthma who were on a combination therapy of inhaled glucocorticoids and long-acting beta agonists.
  • Results showed that 41.7% of patients experienced step-down failure, with significant factors including older age, multiple comorbidities, severity of asthma, and a short duration of previous asthma control.
  • The conclusion emphasizes that successful step-down is more likely when patients have maintained asthma control for over 6 months, suggesting that careful consideration is needed before adjusting treatment.
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Objective: Evaluate cardiac, metabolic, and ventilatory changes during a training session with whole-body vibration training (WBVT) with 3 different frequencies in patients with chronic obstructive pulmonary disease (COPD).

Methods: This was a prospective, interventional trial in outpatients with severe COPD. Participants performed 3 vertical WBVT sessions once a week using frequencies of 35, 25 Hz and no vibration in squatting position (isometric).

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It is well known that chronic obstructive pulmonary disease (COPD) patients present with muscle dysfunction that may not correlate with the degree of severity of airflow obstruction. Historically, the strength deficit of the knee extensor musculature (quadriceps) has been described as an independent factor of mortality in COPD. We present the results of a retrospective study with longitudinal follow-up of 60 patients with severe COPD followed for 7 years.

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Introduction: Pneumonia is considered an independent entity in chronic obstructive pulmonary disease (COPD), to be distinguished from an infectious exacerbation of COPD. The aim of this study was to analyze the clinical characteristics and progress of the exacerbation of COPD (ECOPD) compared to pneumonia in COPD (PCOPD) patients requiring hospitalization.

Patients And Methods: Prospective, longitudinal, observational cohort study including 124 COPD patients requiring hospital admission for lower respiratory tract infection.

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Background: Even after a rehabilitation program, levels of physical activity in COPD progressively decrease unless strategies to encourage activity are implemented. We analyzed the effects of the implementation of urban walking circuits on levels of physical activity and exercise capacity of patients with severe and very severe COPD after a rehabilitation program.

Method: A total of 83 patients were randomized to either urban circuits group (UCG) or usual care in the non-circuit group (NCG), after completing a 2-week rehabilitation program.

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Three potentially toxic elements [chromium (Cr), lead (Pb), and cadmium (Cd)] were tested to assess their effects on two soils of different properties and origin. The soils were a granitic soil (Haplic Arenosol), which meets the requirements of OECD ecotoxicity testing, and a calcareous soil (Calcaric Regosol) with properties often found in the Mediterranean areas. The metal concentrations used ranged from 0.

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The involvement of the bacterial community of an agricultural Mediterranean calcareous soil in relation to several heavy metals has been studied in microcosms under controlled laboratory conditions. Soil samples were artificially polluted with Cr(VI), Cd(II) and Pb(II) at concentrations ranging from 0.1 to 5000 mg kg(-1) and incubated along 28 d.

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Three chlorophenolic compounds (2-chlorophenol, 2,4,6-trichlorophenol, and pentachlorophenol) were tested to assess their effects on two soils with different properties: a granitic soil (Haplic Arenosol) and a calcareous one (Calcaric Regosol). Different concentrations of the pollutants (ranging from 0.001 to 10,000 mg kg(-1) soil, d.

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The impact of 2-monochlorophenol (MCP), 2,4,6-trichlorophenol (TCP) and pentachlorophenol (PCP) on the microbial community of an acidic forest soil was studied under controlled laboratory conditions by spiking microcosms with the pollutants at concentrations ranging from 0.1 to 5000 mg kg(-1). A decrease in the cumulative respirometric values and changes in the bacterial and fungal community composition were detected at 1000 mg MCP kg(-1), 100 mg TCP kg(-1) and 100 and 1000 mg PCP kg(-1).

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The compatible solute N(ɛ)-acetyl-β-lysine (NeABL), thus far considered unique to methanogenic Archaea, has been found to accumulate in several strains of green sulfur bacteria (GSB) and Bacillus cereus CECT 148(T) under salt stress. A similar mixture of compatible solutes including trehalose, α-glutamate, β-glutamate and NeABL has been detected in salt-tolerant GSB strains of different phylogenetic branches. The ability of B.

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To highlight the effects of a variety of chlorophenols (CP) in relation to the response of an indigenous bacterial community, an agricultural Mediterranean calcareous soil has been studied in microcosms incubated under controlled laboratory conditions. Soil samples were artificially polluted with 2-monochlorophenol (MCP), 2,4,6-trichlorophenol (TCP) and pentachlorophenol (PCP), at concentrations ranging from 0.1 up to 5000 mg kg(-1).

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The taxonomic significance of salt tolerance or requirements in green sulfur bacteria has been analyzed with environmental populations and enrichment cultures from several saline systems (inland and coastal water bodies) with different salinities (salt composition and concentration). Novel phylotypes of green sulfur bacteria have been found in hypersaline and brackish environments and 16S rRNA gene sequence analysis affiliated them into phylogenetic groups in which neither halotolerant nor halophilic species have been known to date. Therefore, salt tolerance does not seem to be restricted to members of any specific subgroup but is widespread among all the different phylogenetic branches of the green sulfur bacteria group, and closely-related phylotypes can have dissimilar salt tolerance capacities.

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The goal of this work was to demonstrate the feasibility of treating leachate with high ammonium concentrations using the SBR technology, as a preparative step for the treatment in an anammox reactor. The cycle was based on a step-feed strategy, alternating anoxic and aerobic conditions. Results of the study verified the viability of this process, treating an influent with concentration up to 5000 mg N-NH(4)(+) L(-1).

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This investigation probed for anammox bacterial populations that would be suitable to start-up a biological reactor for N-removal. Samples of sludge and sediments from different environments were screened and used as inoculum for enrichment of anammox bacteria in batch cultures. Enrichments were monitored in order to detect anammox bacteria or their potential activity.

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We report on two diaminotriazine-equipped naphthalene derivatives that bind reversibly to a single-stranded DNA template or "tape-measure molecule" via hydrogen bonding, yielding monodisperse double-stranded DNA hybrids with one strand consisting of a supramolecular naphthalene backbone. These assemblies have been investigated extensively, both experimentally and theoretically. The structure and the templated self-assembly process of the complex have been characterized with UV-vis spectroscopy, circular dichroism spectroscopy, molecular dynamics simulations, cryo-transmission electron microscopy, liquid atomic force microscopy, electrospray ionization mass spectrometry, light scattering, and 1H NMR and infrared spectroscopy.

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Synthesis of the tricyclic core of madangamine alkaloids has been achieved in a 10-step sequence starting from a 4-(aminomethyl)anisole derivative. A Birch reduction and acylation with cyanoacetic acid followed by an intramolecular Michael process renders a polyfunctionalized cis-perhydroisoquinoline. A diastereoselective allylation and reduction of amide, nitrile, and ketone groups leads to a bicyclic alcohol, which undergoes aminocyclization through the nosyl derivative to the diazatricyclic ring.

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Some dithiocarbonates (xanthates) can be converted into ketene monothioacetals through extrusion of sulfur upon treatment with base and an alkylating agent.

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The 'Salada de Chiprana' (Chiprana Lake) is a hypersaline (30-73 per thousand), permanent and shallow lake of endorheic origin in a semi-arid region of the Ebro depression (Aragon, Spain). Magnesium sulfate and sodium chloride represent the main salts of this athalassohaline environment. Anoxic conditions occurred periodically in the bottom layers of the lake during the study period.

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