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Supporting UX Evaluation with Open Text Word Clustering
(2024-09-25) Díaz Oreiro, Ignacio; López Herrera, Gustavo
This research work proposes using word clustering to identify concepts associated with the user experience (UX) evaluation of a version of the standardized User Experience Questionnaire (UEQ), where the usual written of responses is replaced by input through a voice interface. The clusters were made from a Word2vec model of word embeddings that was built based on sentences contributed by participants who evaluated the implementation of the voice interface, using traditional quantitative questionnaires and which they complemented with open text comments. The results show clusters around keywords such as ’assistant’, ’understand’, ’response’ and ’survey’, which allow the identification of words associated with both the voice implementation and the UEQ questionnaire itself, and provide information about attitudes researchers could investigate in more detail about the assistant implemented, for example in a subsequent evaluation to be carried out through a focus group or semi-structured interviews.
Individual and mixture effect of selected high-hazard pharmaceuticals on aquatic primary producers
(2025-04-27) Montiel Mora, José Rolando; Lizano Fallas, Verónica; Méndez Rivera, Michael; Marín González, Alexandra; Cambronero Heinrichs, Juan Carlos; Rodríguez Rodríguez, Carlos E.
The extensive use of pharmaceuticals has led to their occurrence in surface waters due to insufficient treatment processes for their removal. Their environmental impact remains largely unexplored for certain trophic levels, particularly plants and algae. Pharmaceuticals often occur in mixtures with other pollutants, highlighting the need for comprehensive toxicological ssessments that evaluate their combined interactions. This study evaluated the acute toxicity of four high-hazard pharmaceuticals —diphenhydramine, fluoxetine, ketoprofen, and trimethoprim— and their binary mixtures, on the green microalgae Raphidocelis subcapitata and the aquatic macrophyte Lemna gibba. For individual compounds, R. subcapitata growth rate was inhibited in all cases, with fluoxetine, ketoprofen and diphenhydramine exhibiting moderate toxicity (EC 50 = 0.34, 0.14, and 4.88 mg/L, respectively), while trimethoprim showed low toxicity (EC 50 = 332.35 mg/L). Similar trends were observed in L. gibba, except for diphenhydramine, which also showed low toxicity (EC 50 = 26.57 mg/L). Binary mixtures demonstrated a synergistic interaction towards the microalgae in the presence of ketoprofen, except ketoprofen-trimethoprim combination (antagonism, p < 0.0001). In contrast, most interactions in L. gibba exhibited antagonism, except ketoprofen-fluoxetine (synergism, p = 0.0042). Differences were observed between the two model organisms for individual compounds and mixtures. No correlation was found between L. gibba experimental data and QSAR predictions derived from R. subcapitata. Our results highlight the need for: i. further studies including mixtures of relevant pharmaceuticals; ii. caution in the use of predictive models or extrapolation between taxa; and iii. the inclusion of fluoxetine and ketoprofen as priority compounds in future risk assessments.
Metalloproteinases in disease: identification of biomarkers of tissue damage through proteomics
(2018-10-31) Herrera Arias, Cristina; Escalante Muñoz, Teresa; Rucavado Romero, Alexandra; Fox, Jay W.; Gutiérrez, José María
Introduction: Metalloproteinases play key roles in health and disease, by generating novel proteoforms with variable structure and function. Areas covered: This review focuses on the role of endogenous [a Disintegrin and Metalloproteinase (ADAMs), ADAMs with thrombospondin motifs (ADAMTS), and matrix metalloproteinases (MMPs)] and exogenous metalloproteinases in various disease conditions, and describes the application of mass spectrometry-based proteomics to detect qualitative and quantitative changes in protein profiles in tissues and body fluids in disease. Emphasis is placed on the proteomic analysis of exudates collected from affected tissues, including methods that enrich newly generated protein fragments derived from proteolysis in cells, stroma, or extracellular matrix. The use of proteomic analysis of exudates in the study of the local tissue damage induced by metalloproteinases derived from viperid snake venoms is discussed, particularly in relation to extracellular matrix degradation and to the overall pathology of these envenomings. Expert commentary: The information provided by these proteomics approaches is paving the way for the identification of biomarkers based on particular proteolytic signatures associated with different pathologies. Together with other methodological approaches, a comprehensive view of the mechanisms and dynamics of diseases can be achieved. Such basis of knowledge allows for the design of novel diagnostic and therapeutic approaches within the frame of ‘precision’ or ‘personalized’ medicine.
Isolation and biological characterization of Batx-I, a weak hemorrhagic and fibrinogenolytic PI metalloproteinase from Colombian Bothrops atrox venom
(2010-06-30) Patiño Llano, Arley Camilo; Pereañez, Jaime Andrés; Núñez Rangel, Vitelbina; Benjumea, Dora María; Fernández Culma, Maritza; Rucavado Romero, Alexandra; Sanz, Libia; Calvete Chornet, Juan José
A hemorrhagic metalloproteinase, named Batx-I, was isolated from the venom of Bothrops atrox specimens (from Southeastern Colombian region) by a combination of CM-Sephadex C25 ion-exchange and Affi-gel Blue affinity chromatographies. This enzyme accounts for about 45% of venom proteins, and it has an ESI-MS isotope-averaged molecular mass of 23296.2 Da and a blocked N-terminus. Two internal fragments sequenced by mass spec trometric analysis showed similarity to other SVMPs from Bothrops venoms. To investigate the possible participation of Batx-I in the envenomation pathophysiology, proteolytic, f ibrinogenolytic, hemorrhagic, and other biological activities were evaluated. The minimal hemorrhagic dose obtained was 17 mg/20 g body weight. The enzyme showed proteolytic activity on azocasein, comparable with activity of BaP1. This activity was inhibited by EDTA and 1, 10 o-phenanthroline but not by aprotinin, pepstatin A or PMSF. Fibrinogenolytic activity was analyzed by SDS-PAGE, revealing a preference for degrading the Aa- and Bb-chains, although partial degradation of the g-chain was also detected. The protein lacks coagulant and defibrinating activity. The CK levels obtained, clearly reflects a myotoxic activity induced by Batx-I. The hemorrhagic and fibrinogenolytic activities exhibited by the isolated PI-SVMP may play a role in the hemorrhagic and blood-clotting disorders observed in patients bitten by B. atrox in Colombia.
Synthesis, crystal structures, reactivity, and theoretical evaluations of aromatic pincer ligands with OCO-chelation motifs
(2026-01-05) Garita Salazar, Bruno; Jürgen H., Antony; Corrales Ugalde, Amanda; Camacho, Cristopher; Pineda Cedeño, Leslie William
Pincer ligands bearing XCX-type scaffolds (X = N, P, S) have gained a great deal of attention as they allow the isolation of well-designed metal complexes, resulting in appealing structural and stereoelectronic features. In the present work, we report on the synthesis and characterization of a novel series of OCO conformation pincer ligands based on aryl benzyl ether structures, [(ROCH2)2C6H4], which contain unreported aromatic terminal units, where R = 2,6-dimethylphenyl (3a), 2,5-dimethylphenyl (3b), 2,4-dimethylphenyl (3c), [1,1′-biphenyl]-3-yl] (3d), [1,1′-biphenyl]-4-yl] (3e), and pentachlorophenyl (3f). Our rationale for choosing these fragments of aromatic derivatives ( OR terminal units) is to provide points of electronic modulation on the ligands as well as thermodynamic and kinetic properties. We accomplished the molecular structure of compounds 3a and 3e in the crystalline state by single-crystal X-ray structural analysis. Further, we emonstrate the reactivity of pincer ligand 3a in the presence of an organolithium reagent to afford the corresponding organolithium pincer compound 2,6-bis(2,6-dimethylphenoxy)methyl)phenyllithium (4). Interestingly, 4 proved highly stable over time, existing as dimers both in solid- and in solution-state as revealed by crystal structure and multinuclear and 2D NMR spectroscopy experiments, respectively. Finally, DFT calculations further assess the bonding situation for
compounds 3a and 3e.