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1.
Artículo en Inglés | MEDLINE | ID: mdl-38700618

RESUMEN

This study assessed the efficacy of an Ammodaucus leucotrichus seed extract to treat rheumatoid arthritis in rat models of this disease. Rheumatoid arthritis was induced in rats using two methods: immunization with 100 µL of Complete Freund Adjuvant (CFA) and immunization with 100 µL of a 3 mg/ml solution of type II collagen (CII) from chicken cartilage. The therapeutic potential of the extract was assessed at different doses (150, 300, and 600 mg/kg/day for 21 days in the CII-induced arthritis model and for 14 days in the CFA-induced arthritis model) and compared with methotrexate (MTX; 0.2 mg/kg for the same periods), a commonly used drug for rheumatoid arthritis treatment in humans. In both models (CII-induced arthritis and CFA-induced arthritis), walking distance, step length, intra-step distance and footprint area were improved following treatment with the A. leucotrichus seed extract (all concentrations) and MTX compared with untreated animals. Both treatments increased the serum concentration of glutathione and reduced that of complement C3, malondialdehyde and myeloperoxidase. Radiographic data and histological analysis indicated that cartilage destruction was reduced already with the lowest dose of the extract (100 mg/kg/dose) in both models. These results show the substantial antiarthritic potential of the A. leucotrichus seed extract, even at the lowest dose, suggesting that it may be a promising alternative therapy for rheumatoid arthritis and joint inflammation. They also emphasize its efficacy at various doses, providing impetus for more research on this extract as a potential therapeutic agent for arthritis.

2.
Pharmaceuticals (Basel) ; 17(3)2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38543170

RESUMEN

Ammodaucus leucotrichus exhibits promising pharmacological activity, hinting at anti-inflammatory and anti-arthritic effects. This study investigated seed extracts from Ammodaucus leucotrichus using methanol and n-hexane, focusing on anti-inflammatory and anti-arthritic properties. The methanol extract outperformed the n-hexane extract and diclofenac, a reference anti-inflammatory drug, in trypsin inhibition (85% vs. 30% and 64.67% at 125 µg/mL). For trypsin inhibition, the IC50 values were 82.97 µg/mL (methanol), 202.70 µg/mL (n-hexane), and 97.04 µg/mL (diclofenac). Additionally, the n-hexane extract surpassed the methanol extract and diclofenac in BSA (bovine serum albumin) denaturation inhibition (90.4% vs. 22.0% and 51.4% at 62.5 µg/mL). The BSA denaturation IC50 values were 14.30 µg/mL (n-hexane), 5408 µg/mL (methanol), and 42.30 µg/mL (diclofenac). Gas chromatography-mass spectrometry (GC-MS) revealed 59 and 58 secondary metabolites in the methanol and n-hexane extracts, respectively. The higher therapeutic activity of the methanol extract was attributed to hydroxyacetic acid hydrazide, absent in the n-hexane extract. In silico docking studies identified 28 compounds with negative binding energies, indicating potential trypsin inhibition. The 2-hydroxyacetohydrazide displayed superior inhibitory effects compared to diclofenac. Further mechanistic studies are crucial to validate 2-hydroxyacetohydrazide as a potential drug candidate for rheumatoid arthritis treatment.

3.
RNA ; 30(6): 662-679, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38443115

RESUMEN

Despite being predicted to lack coding potential, cytoplasmic long noncoding (lnc)RNAs can associate with ribosomes. However, the landscape and biological relevance of lncRNA translation remain poorly studied. In yeast, cytoplasmic Xrn1-sensitive unstable transcripts (XUTs) are targeted by nonsense-mediated mRNA decay (NMD), suggesting a translation-dependent degradation process. Here, we report that XUTs are pervasively translated, which impacts their decay. We show that XUTs globally accumulate upon translation elongation inhibition, but not when initial ribosome loading is impaired. Ribo-seq confirmed ribosomes binding to XUTs and identified ribosome-associated 5'-proximal small ORFs. Mechanistically, the NMD-sensitivity of XUTs mainly depends on the 3'-untranslated region length. Finally, we show that the peptide resulting from the translation of an NMD-sensitive XUT reporter exists in NMD-competent cells. Our work highlights the role of translation in the posttranscriptional metabolism of XUTs. We propose that XUT-derived peptides could be exposed to natural selection, while NMD restricts XUT levels.


Asunto(s)
Exorribonucleasas , Degradación de ARNm Mediada por Codón sin Sentido , Biosíntesis de Proteínas , ARN Largo no Codificante , Ribosomas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Exorribonucleasas/metabolismo , Exorribonucleasas/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ribosomas/metabolismo , Ribosomas/genética , Regiones no Traducidas 3' , Sistemas de Lectura Abierta , ARN Mensajero/genética , ARN Mensajero/metabolismo , Estabilidad del ARN
4.
Front Chem ; 12: 1367552, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38449480

RESUMEN

Ephedra alata leaf extracts have therapeutic properties and contain various natural compounds known as phytochemicals. This study assessed the phytochemical content and antioxidant effects of a Ephedra alata leaf extract, as well as zinc oxide (ZnO) nanoparticle production. The extract contained phenolic acids, including vanillic acid, chlorogenic acid, gallic acid, p-coumaric acid, vanillin and rutin. Its total phenolic content and total flavonoid content were 48.7 ± 0.9 mg.g-1 and 1.7 ± 0.4 mg.g-1, respectively. The extract displayed a DPPH inhibition rate of 70.5%, total antioxidant activity of 49.5 ± 3.4 mg.g-1, and significant antimicrobial activity toward Gram-positive and negative bacteria. The synthesized ZnO nanoparticles had spherical shape, crystallite size of 25 nm, particle size between 5 and 30 nm, and bandgap energy of 3.3 eV. In specific conditions (90 min contact time, pH 7, and 25°C), these nanoparticles efficiently photodegraded 87% of methylene blue, suggesting potential applications for sustainable water treatment and pollution control.

5.
Chembiochem ; 25(7): e202300768, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38353030

RESUMEN

Growing cells in a biomimetic environment is critical for tissue engineering as well as for studying the cell biology underlying disease mechanisms. To this aim a range of 3D matrices have been developed, from hydrogels to decellularized matrices. They need to mimic the extracellular matrix to ensure the optimal growth and function of cells. Electrospinning has gained in popularity due to its capacity to individually tune chemistry and mechanical properties and as such influence cell attachment, differentiation or maturation. Polyacrylonitrile (PAN) derived electrospun fibres scaffolds have shown exciting potential due to reports of mechanical tunability and biocompatibility. Building on previous work we fabricate here a range of PAN fibre scaffolds with different concentrations of carbon nanotubes. We characterize them in-depth in respect to their structure, surface chemistry and mechanical properties, using scanning electron microscopy, image processing, ultramicrotomic transmission electron microscopy, x-ray nanotomography, infrared spectroscopy, atomic force microscopy and nanoindentation. Together the data demonstrate this approach to enable finetuning the mechanical properties, while keeping the structure and chemistry unaltered and hence offering ideal properties for comparative studies of the cellular mechanobiology. Finally, we confirm the biocompatibility of the scaffolds using primary rat cardiomyocytes, vascular smooth muscle (A7r5) and myoblast (C2C12) cell lines.


Asunto(s)
Nanotubos de Carbono , Andamios del Tejido , Animales , Ratas , Andamios del Tejido/química , Ingeniería de Tejidos/métodos , Resinas Acrílicas
6.
Res Microbiol ; 175(4): 104177, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38159786

RESUMEN

S. lividans and S. coelicolor are phylogenetically closely related strains with different abilities to produce the same specialized metabolites. Previous studies revealed that the strong antibiotic producer, S. coelicolor, had a lower ability to assimilate nitrogen and phosphate than the weak producer, Streptomyces lividans, and this resulted into a lower growth rate. A comparative proteomic dataset was used to establish the consequences of these nutritional stresses on the abundance of proteins of the translational apparatus of these strains, grown in low and high phosphate availability. Our study revealed that most proteins of the translational apparatus were less abundant in S. coelicolor than in S. lividans whereas it was the opposite for ET-Tu 3 and a TrmA-like methyltransferase. The expression of the latter being known to be under the positive control of the stringent response whereas that of the other ribosomal proteins is under its negative control, this indicated the occurrence of a strong activation of the stringent response in S. coelicolor. Furthermore, in S. lividans, ribosomal proteins were more abundant in phosphate proficiency than in phosphate limitation suggesting that a limitation in phosphate, that was also shown to trigger RelA expression, contributes to the induction of the stringent response.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Regulación Bacteriana de la Expresión Génica , Fosfatos , Streptomyces coelicolor , Streptomyces coelicolor/metabolismo , Streptomyces coelicolor/genética , Streptomyces coelicolor/crecimiento & desarrollo , Antibacterianos/biosíntesis , Antibacterianos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Fosfatos/metabolismo , Streptomyces lividans/metabolismo , Streptomyces lividans/genética , Proteoma , Proteínas Ribosómicas/metabolismo , Proteínas Ribosómicas/genética , Biosíntesis de Proteínas , Nitrógeno/metabolismo , Proteómica , Estrés Fisiológico
7.
Chem Commun (Camb) ; 59(92): 13719-13722, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37909229

RESUMEN

We report the proof-of-concept of spark plasma sintered (SPS) consolidated mesoporous composite catalytic electrodes based on nickel-copper alloys and carbon nanotubes for the electrocatalytic hydrogen evolution reaction (HER) in alkaline media. The optimized electrode (203 m2 g-1, 5 wt% Ni75Cu25) operated at -0.1 A cm-2 (current of -0.15 A) for 24 h with a stable overpotential of about 0.3 V. This newly described freestanding SPS approach allows the rational control of specific surface area, metal loading, and electrocatalytic performance, thus opening a new route to catalytic electrodes with controllable physical and catalytic properties.

8.
Molecules ; 28(22)2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-38005261

RESUMEN

Catalytic transfer hydrogenation has emerged as a pivotal chemical process with transformative potential in various industries. This review highlights the significance of catalytic transfer hydrogenation, a reaction that facilitates the transfer of hydrogen from one molecule to another, using a distinct molecule as the hydrogen source in the presence of a catalyst. Unlike conventional direct hydrogenation, catalytic transfer hydrogenation offers numerous advantages, such as enhanced safety, cost-effective hydrogen donors, byproduct recyclability, catalyst accessibility, and the potential for catalytic asymmetric transfer hydrogenation, particularly with chiral ligands. Moreover, the diverse range of hydrogen donor molecules utilized in this reaction have been explored, shedding light on their unique properties and their impact on catalytic systems and the mechanism elucidation of some reactions. Alcohols such as methanol and isopropanol are prominent hydrogen donors, demonstrating remarkable efficacy in various reductions. Formic acid offers irreversible hydrogenation, preventing the occurrence of reverse reactions, and is extensively utilized in chiral compound synthesis. Unconventional donors such as 1,4-cyclohexadiene and glycerol have shown a good efficiency in reducing unsaturated compounds, with glycerol additionally serving as a green solvent in some transformations. The compatibility of these donors with various catalysts, substrates, and reaction conditions were all discussed. Furthermore, this paper outlines future trends which include the utilization of biomass-derived hydrogen donors, the exploration of hydrogen storage materials such as metal-organic frameworks (MOFs), catalyst development for enhanced activity and recyclability, and the utilization of eco-friendly solvents such as glycerol and ionic liquids. Innovative heating methods, diverse base materials, and continued research into catalyst-hydrogen donor interactions are aimed to shape the future of catalytic transfer hydrogenation, enhancing its selectivity and efficiency across various industries and applications.

9.
Molecules ; 28(16)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37630385

RESUMEN

Polysulfone (PSF) is one of the most used polymers for water treatment membranes, but its intrinsic hydrophobicity can be detrimental to the membranes' performances. By modifying a membrane's surface, it is possible to adapt its physicochemical properties and thus tune the membrane's hydrophilicity or porosity, which can achieve improved permeability and antifouling efficiency. Atomic layer deposition (ALD) stands as a distinctive technology offering exceedingly even and uniform layers of coatings, like oxides that cover the surfaces of objects with three-dimensional (3D) shapes, porous structures, and particles. In the context of this study, the focus was on titanium dioxide (TiO2), zinc oxide (ZnO), and alumina (Al2O3), which were deposited on polysulfone hollow fiber (HF) membranes via ALD using TiCl4, diethyl zinc (DEZ), and trimethylamine (TMA), respectively, and H2O as precursors. The morphology and mechanical properties of membranes were changed without damaging their performances. The deposition was confirmed mainly by energy-dispersive X-ray spectroscopy (EDX). All depositions offered great performances with a maintained permeability and BSA retention and a 20 to 40° lower water contact angle (WCA) than the raw PSF HF membrane. The deposition of TiO2 offered the best results, showing an enhancement of 50% for the water permeability and 20% for the fouling resistance of the PSF HF membranes.

10.
Nanomaterials (Basel) ; 13(14)2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37513130

RESUMEN

The many pollutants detected in water represent a global environmental issue. Emerging and persistent organic pollutants are particularly difficult to remove using traditional treatment methods. Electro-oxidation and sulfate-radical-based advanced oxidation processes are innovative removal methods for these contaminants. These approaches rely on the generation of hydroxyl and sulfate radicals during electro-oxidation and sulfate activation, respectively. In addition, hybrid activation, in which these methods are combined, is interesting because of the synergistic effect of hydroxyl and sulfate radicals. Hybrid activation effectiveness in pollutant removal can be influenced by various factors, particularly the materials used for the anode. This review focuses on various organic pollutants. However, it focuses more on pharmaceutical pollutants, particularly paracetamol, as this is the most frequently detected emerging pollutant. It then discusses electro-oxidation, photocatalysis and sulfate radicals, highlighting their unique advantages and their performance for water treatment. It focuses on perovskite oxides as an anode material, with a particular interest in calcium copper titanate (CCTO), due to its unique properties. The review describes different CCTO synthesis techniques, modifications, and applications for water remediation.

11.
Nanomaterials (Basel) ; 13(11)2023 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-37299616

RESUMEN

The electrocatalytic oxidation of glycerol by metal electrocatalysts is an effective method of low-energy-input hydrogen production in membrane reactors in alkaline conditions. The aim of the present study is to examine the proof of concept for the gamma-radiolysis-assisted direct growth of monometallic gold and bimetallic gold-silver nanostructured particles. We revised the gamma radiolysis procedure to generate free-standing Au and Au-Ag nano- and micro-structured particles onto a gas diffusion electrode by the immersion of the substrate in the reaction mixture. The metal particles were synthesized by radiolysis on a flat carbon paper in the presence of capping agents. We have integrated different methods (SEM, EDX, XPS, XRD, ICP-OES, CV, and EIS) to examine in detail the as-synthesized materials and interrogate their electrocatalytic efficiency for glycerol oxidation under baseline conditions to establish a structure-performance relationship. The developed strategy can be easily extended to the synthesis by radiolysis of other types of ready-to-use metal electrocatalysts as advanced electrode materials for heterogeneous catalysis.

12.
Membranes (Basel) ; 13(2)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36837707

RESUMEN

In this study, we combined electrospinning of a large amount of halloysite (HNT, 95%) with nitriding to produce N-HNT-TiO2 composite nanofibers (N-H95T5 hereafter) to be used for acetaminophen (ACT) photodegradation. Investigation of the morphological and structural properties of the obtained materials did not highlight any significant difference in their morphological features and confirmed that nitrogen was evenly distributed in the samples. Photocatalytic tests under visible light showed that acetaminophen photodegraded faster in the presence of samples with nitrogen (N-H95T5) than without (H95T5 nanofibers). Moreover, the N-H95T5 nanocomposite photocatalytic activity did not change after repeated utilization (five cycles). The addition of scavengers during photocatalytic tests showed the key implication of OH•-, O2•- and h+ radicals in acetaminophen degradation. These results indicated that N-H95T5 composite nanofibers could be considered a cheap multifunctional material for photodegradation and could open new prospects for preparing tunable photocatalysts.

13.
Chem Commun (Camb) ; 59(1): 47-50, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36468687

RESUMEN

We report the combination of electrospinning and calcination to synthesize many free-standing electrocatalytic electrodes made of nanostructured nickel particles (active sites) and three-dimensional carbon microfibers (support). Precisely, we have used five different nickel precursors to elucidate the nitrogen origin (polyacrylonitrile or metal salts) and the impact on the electrocatalytic properties.

14.
Materials (Basel) ; 15(12)2022 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-35744395

RESUMEN

Electrochemical converters (electrolyzers, fuel cells, and batteries) have gained prominence during the last decade for the unavoidable energy transition and the sustainable synthesis of platform chemicals. One of the key elements of these systems is the electrode material on which the electrochemical reactions occur, and therefore its design will impact their performance. This review focuses on the electrospinning method by examining a number of features of experimental conditions. Electrospinning is a fiber-spinning technology used to produce three-dimensional and ultrafine fibers with tunable diameters and lengths. The thermal treatment and the different analyses are discussed to understand the changes in the polymer to create usable electrode materials. Electrospun fibers have unique properties such as high surface area, high porosity, tunable surface properties, and low cost, among others. Furthermore, a little introduction to the 5-hydroxymethylfurfural (HMF) electrooxidation coupled to H2 production was included to show the benefit of upgrading biomass derivates in electrolyzers. Indeed, environmental and geopolitical constraints lead to shifts towards organic/inorganic electrosynthesis, which allows for one to dispense with polluting, toxic and expensive reagents. The electrooxidation of HMF instead of water (OER, oxygen evolution reaction) in an electrolyzer can be elegantly controlled to electro-synthesize added-value organic chemicals while lowering the required energy for CO2-free H2 production.

15.
Biophys J ; 121(13): 2514-2525, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35659635

RESUMEN

High pressure (HP) is a particularly powerful tool to study protein folding/unfolding, revealing subtle structural rearrangements. Bovine ß-lactoglobulin (BLG), a protein of interest in food science, exhibits a strong propensity to bind various bioactive molecules. We probed the effects of the binding of biliverdin (BV), a tetrapyrrole linear chromophore, on the stability of BLG under pressure, by combining in situ HP small-angle neutron scattering (SANS) and HP-UV absorption spectroscopy. Although BV induces a slight destabilization of BLG during HP-induced unfolding, a ligand excess strongly prevents BLG oligomerization. Moreover, at SANS resolution, an excess of BV induces the complete recovery of the protein "native" 3D structure after HP removal, despite the presence of the BV covalently bound adduct. Mass spectrometry highlights the crucial role of cysteine residues in the competitive and protective effects of BV during pressure denaturation of BLG through SH/S-S exchange.


Asunto(s)
Biliverdina , Lactoglobulinas , Animales , Bovinos , Cisteína , Lactoglobulinas/química , Desplegamiento Proteico
16.
ACS Appl Bio Mater ; 5(6): 3075-3085, 2022 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-35584545

RESUMEN

The aim of this work was the development of injectable radio-opaque and macroporous calcium phosphate cement (CPC) to be used as a bone substitute for the treatment of pathologic vertebral fractures. A CPC was first rendered radio-opaque by the incorporation of zirconium dioxide (ZrO2). In order to create macroporosity, poly lactic-co-glycolic acid (PLGA) microspheres around 100 µm were homogeneously incorporated into the CPC as observed by scanning electron microscopy. Physicochemical analyses by X-ray diffraction and Fourier transform infrared spectroscopy confirmed the brushite phase of the cement. The mechanical properties of the CPC/PLGA cement containing 30% PLGA (wt/wt) were characterized by a compressive strength of 2 MPa and a Young's modulus of 1 GPa. The CPC/PLGA exhibited initial and final setting times of 7 and 12 min, respectively. Although the incorporation of PLGA microspheres increased the force necessary to inject the cement and decreased the percentage of injected mass as a function of time, the CPC/PLGA appeared fully injectable at 4 min. Moreover, in comparison with CPC, CPC/PLGA showed a full degradation in 6 weeks (with 100% mass loss), and this was associated with an acidification of the medium containing the CPC/PLGA sample (pH of 3.5 after 6 weeks). A cell viability test validated CPC/PLGA biocompatibility, and in vivo analyses using a bone defect assay in the caudal vertebrae of Wistar rats showed the good opacity of the CPC through the tail and a significant increased degradation of the CPC/PLGA cement a month after implantation. In conclusion, this injectable CPC scaffold appears to be an interesting material for bone substitution.


Asunto(s)
Ácido Láctico , Ácido Poliglicólico , Animales , Cementos para Huesos/farmacología , Fosfatos de Calcio/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratas , Ratas Wistar
17.
New Phytol ; 234(3): 1003-1017, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35119708

RESUMEN

Strigolactones (SLs) are plant hormones and important signalling molecules required to promote arbuscular mycorrhizal (AM) symbiosis. While in plants an α/ß-hydrolase, DWARF14 (D14), was shown to act as a receptor that binds and cleaves SLs, the fungal receptor for SLs is unknown. Since AM fungi are currently not genetically tractable, in this study, we used the fungal pathogen Cryphonectria parasitica, for which gene deletion protocols exist, as a model, as we have previously shown that it responds to SLs. By means of computational, biochemical and genetic analyses, we identified a D14 structural homologue, CpD14. Molecular homology modelling and docking support the prediction that CpD14 interacts with and hydrolyses SLs. The recombinant CpD14 protein shows α/ß hydrolytic activity in vitro against the SLs synthetic analogue GR24; its enzymatic activity requires an intact Ser/His/Asp catalytic triad. CpD14 expression in the d14-1 loss-of-function Arabidopsis thaliana line did not rescue the plant mutant phenotype. However, gene inactivation by knockout homologous recombination reduced fungal sensitivity to SLs. These results indicate that CpD14 is involved in SLs responses in C. parasitica and strengthen the role of SLs as multifunctional molecules acting in plant-microbe interactions.


Asunto(s)
Ascomicetos , Proteínas de Plantas , Ascomicetos/metabolismo , Compuestos Heterocíclicos con 3 Anillos , Lactonas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/metabolismo
18.
Commun Biol ; 5(1): 126, 2022 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-35149763

RESUMEN

KAI2 proteins are plant α/ß hydrolase receptors which perceive smoke-derived butenolide signals and endogenous, yet unidentified KAI2-ligands (KLs). The number of functional KAI2 receptors varies among species and KAI2 gene duplication and sub-functionalization likely plays an adaptative role by altering specificity towards different KLs. Legumes represent one of the largest families of flowering plants and contain many agronomic crops. Prior to their diversification, KAI2 underwent duplication resulting in KAI2A and KAI2B. Here we demonstrate that Pisum sativum KAI2A and KAI2B are active receptors and enzymes with divergent ligand stereoselectivity. KAI2B has a higher affinity for and hydrolyses a broader range of substrates including strigolactone-like stereoisomers. We determine the crystal structures of PsKAI2B in apo and butenolide-bound states. The biochemical, structural, and mass spectra analyses of KAI2s reveal a transient intermediate on the catalytic serine and a stable adduct on the catalytic histidine, confirming its role as a bona fide enzyme. Our work uncovers the stereoselectivity of ligand perception and catalysis by diverged KAI2 receptors and proposes adaptive sensitivity to KAR/KL and strigolactones by KAI2B.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Catálisis , Pisum sativum/genética , Pisum sativum/metabolismo , Percepción , Reguladores del Crecimiento de las Plantas/genética
19.
Polymers (Basel) ; 14(3)2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35160596

RESUMEN

Hydrogen peroxide (H2O2) is a key chemical for many industrial applications, yet it is primarily produced by the energy-intensive anthraquinone process. As part of the Power-to-X scenario of electrosynthesis, the controlled oxygen reduction reaction (ORR) can enable the decentralized and renewable production of H2O2. We have previously demonstrated that self-supported electrocatalytic materials derived from polyaniline by chemical oxidative polymerization have shown promising activity for the reduction of H2O to H2 in alkaline media. Herein, we interrogate whether such materials could also catalyze the electro-conversion of O2-to-H2O2 in an alkaline medium by means of a selective two-electron pathway of ORR. To probe such a hypothesis, nine sets of polyaniline-based materials were synthesized by controlling the polymerization of aniline in the presence or not of nickel (+II) and cobalt (+II), which was followed by thermal treatment under air and inert gas. The selectivity and faradaic efficiency were evaluated by complementary electroanalytical methods of rotating ring-disk electrode (RRDE) and electrolysis combined with spectrophotometry. It was found that the presence of cobalt species inhibits the performance. The selectivity towards H2O2 was 65-80% for polyaniline and nickel-modified polyaniline. The production rate was 974 ± 83, 1057 ± 64 and 1042 ± 74 µmolH2O2 h-1 for calcined polyaniline, calcined nickel-modified polyaniline and Vulcan XC 72R (state-of-the-art electrocatalyst), respectively, which corresponds to 487 ± 42, 529 ± 32 and 521 ± 37 mol kg-1cat h-1 (122 ± 10, 132 ± 8 and 130 ± 9 mol kg-1cat cm-2) for faradaic efficiencies of 58-78%.

20.
Cell Mol Neurobiol ; 42(6): 1909-1920, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33740172

RESUMEN

Glioblastoma multiforme (GBM) is account for 70% of all primary malignancies of the central nervous system. The median survival of human patients after treatment is around 15 months. There are several biological targets which have been reported that can be pursued using ligands with varied structures to treat this disease. In our group, we have developed several ligands that target a wide range of proteins involved in anticancer effects, such as histone deacetylase (HDACs), G protein-coupled estrogen receptor 1 (GPER), estrogen receptor-beta (ERß) and NADPH oxidase (NOX), that were screened on bidimensional (2D) and tridimensional (3D) GBM stem cells like (GSC). Our results show that some HDAC inhibitors show antiproliferative properties at 21-32 µM. These results suggest that in this 3D culture, HDACs could be the most relevant targets that are modulated to induce the antiproliferative effects that require in the future further experimental studies.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular , Glioblastoma/patología , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas , Humanos , Ligandos
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