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1.
J Environ Sci (China) ; 140: 292-305, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38331509

RESUMEN

Integrated CO2 capture and utilization (ICCU) technology requires dual functional materials (DFMs) to carry out the process in a single reaction system. The influence of the calcination atmosphere on efficiency of 4% Ru-8% Na2CO3-8% CaO/γ-Al2O3 DFM is studied. The adsorbent precursors are first co-impregnated onto alumina and calcined in air. Then, Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols: static air in muffle or under different mixtures (10% H2/N2, 50% H2/N2 and N2) streams. Samples are characterized by XRD, N2 adsorption-desorption, H2 chemisorption, TEM, XPS, H2-TPD, H2-TPR, CO2-TPD and TPSR. The catalytic behavior is evaluated, in cycles of CO2 adsorption and hydrogenation to CH4, and temporal evolution of reactants and products concentrations is analyzed. The calcination atmosphere influences the physicochemical properties and, ultimately, activity of DFMs. Characterization data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic activity. DFM calcined under N2 flow (RuNaCa-N2) shows the highest CH4 production (449 µmol/g at 370°C), because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases, maximizing the specific surface area, the Ru-basic sites interface and the participation of different basic sites in the CO2 methanation reaction. Thus, the calcination in a N2 flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO2 adsorption and hydrogenation applications.


Asunto(s)
Óxido de Aluminio , Dióxido de Carbono , Adsorción , Hidrogenación , Atmósfera , Iones
2.
High Blood Press Cardiovasc Prev ; 29(5): 463-468, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35904750

RESUMEN

INTRODUCTION: The optimal anti-thrombotic therapy to prevent recurrent ischemic events in patients with acute coronary syndrome and coronary artery ectasia (CAE) remains unclear. AIM: To assess the efficacy and safety of antiplatelet plus anticoagulant therapy versus dual antiplatelet therapy in patients with acute coronary syndromes and coronary artery ectasia. METHODS: OVER-TIME is an investigator initiated, exploratory, open label, single center, randomized clinical trial comparing dual antiplatelet therapy (acetyl-salicylic acid plus a P2Y12 inhibitor) with the combination of an antiplatelet monotherapy (a P2Y12 inhibitor) plus a low dose anticoagulant (rivaroxaban, 15mg oral dose) for the prevention of recurrent ischemic events among patients with CAE. We aim to enroll approximately 60 patients with CAE and acute coronary syndromes. After recruitment, patients are randomized to (a) standard of care (dual antiplatelet regimen) or (b) the combination of antiplatelet monotherapy and low dose anticoagulant. Patients will be followed for at least 12 months. The OVER-TIME study aims to assess the efficacy of the regimen in prevention of major cardiovascular events and its security in bleeding events in acute coronary syndromes among patients with CAE. Expected results and conclusions: OVER-TIME is the first randomized controlled trial to assess different antithrombotic strategies in patients with CAE and acute coronary syndrome, and its results will offer preliminary data for the prevention of major cardiovascular events and bleeding events in this group of patients. TRIAL REGISTRATION NUMBER: NCT05233124 (ClinicalTrials.gov), date of registration: February 10, 2022.


Asunto(s)
Síndrome Coronario Agudo , Intervención Coronaria Percutánea , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/tratamiento farmacológico , Anticoagulantes/efectos adversos , Vasos Coronarios , Dilatación Patológica/inducido químicamente , Dilatación Patológica/tratamiento farmacológico , Quimioterapia Combinada , Fibrinolíticos/efectos adversos , Hemorragia/inducido químicamente , Humanos , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Inhibidores de Agregación Plaquetaria/efectos adversos , Rivaroxabán , Ácido Salicílico/uso terapéutico , Resultado del Tratamiento
3.
Rev. cuba. reumatol ; 23(2)ago. 2021.
Artículo en Español | LILACS, CUMED | ID: biblio-1409164

RESUMEN

RESUMEN La gonartrosis es una entidad muy frecuente y afecta a un grupo numeroso de pacientes en especial a los mayores de 40 años. El tratamiento conservador constituye la primera línea e incluye la proloterapia. El propósito de este estudio es actualizar los conocimientos en relación al uso de la proloterapia en pacientes con gonartrosis. La búsqueda y análisis de la información se realizó en un periodo de 2 meses (primero de febrero de 2020 al 30 de abril de 2020) y se emplearon las siguientes palabras: prolotherapy, regenerative injection therapy and chronic musculoskeletal pain. A partir de la información obtenida se realizó una revisión bibliográfica de un total de 203 artículos publicados en las bases de datos PubMed, Hinari, SciELO y Medline mediante el gestor de búsqueda y administrador de referencias EndNote, de ellos se utilizaron 39 citas seleccionadas para realizar la revisión, de ellas 32 de los últimos cinco años, además se consultó un libro. Se mencionan las concentraciones a emplear tanto intra- como periarticular, indicaciones y mecanismos de acción. Se describen la frecuencia de su aplicación, así como la comparación con otros métodos de tratamiento por vía intraarticular. Se hace referencia a la duración de su efecto y complicaciones. La proloterapia mediante la administración de dextrosa hipertónica intraarticular es un método útil en el tratamiento de pacientes con gonartrosis, su fácil aplicación, disponibilidad y bajo índice de complicaciones lo convierten en un método conservador factible y eficaz.


ABSTRACT Gonarthrosis is a very frequent entity and affects a large group of patients especially above 40 years, conservative treatment is the first line and includes prolotherapy. To update knowledge regarding the use of prolotherapy in patients with gonarthrosis. The information was searched and analyzed over a period of two months (February 1, 2020 to April 30, 2020) and the following words were used: prolotherapy, regenerative injection therapy and chronic musculoskeletal pain. Based on the information obtained, a bibliographic review of a total of 203 articles published in the PubMed, Hinari, SciELO and Medline databases was carried out using the search manager and reference manager EndNote, 39 selected citations were used to make the review, including 32 of the last five years, also consulted a book. The concentrations to be used both intra and periarticular, indications and mechanisms of action are mentioned. The frequency of its application is described, as well as the comparison with other intra-articular treatment methods. Reference is made to the duration of its effect and complications. Prolotherapy by administering intra-articular hypertonic dextrose is a useful method in the treatment of patients with gonarthrosis, its easy application, availability and low complication rate make it a feasible and effective conservative method.


Asunto(s)
Humanos , Dolor Musculoesquelético/terapia , Proloterapia/métodos
4.
Sci Rep ; 10(1): 22154, 2020 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-33335113

RESUMEN

Existing methods for testing prosthetic implants suffer from critical limitations, creating an urgent need for new strategies that facilitate research and development of implants with enhanced osseointegration potential. Herein, we describe a novel, biomimetic, human bone platform for advanced testing of implants in vitro, and demonstrate the scientific validity and predictive value of this approach using an assortment of complementary evaluation methods. We anchored titanium (Ti) and stainless steel (SS) implants into biomimetic scaffolds, seeded with human induced mesenchymal stem cells, to recapitulate the osseointegration process in vitro. We show distinct patterns of gene expression, matrix deposition, and mineralization in response to the two materials, with Ti implants ultimately resulting in stronger integration strength, as seen in other preclinical and clinical studies. Interestingly, RNAseq analysis reveals that the TGF-beta and the FGF2 pathways are overexpressed in response to Ti implants, while the Wnt, BMP, and IGF pathways are overexpressed in response to SS implants. High-resolution imaging shows significantly increased tissue mineralization and calcium deposition at the tissue-implant interface in response to Ti implants, contributing to a twofold increase in pullout strength compared to SS implants. Our technology creates unprecedented research opportunities towards the design of implants and biomaterials that can be personalized, and exhibit enhanced osseointegration potential, with reduced need for animal testing.


Asunto(s)
Materiales Biomiméticos , Biomimética , Huesos , Prótesis e Implantes , Ingeniería de Tejidos , Biomimética/métodos , Humanos , Ensayo de Materiales , Oseointegración , Acero Inoxidable , Ingeniería de Tejidos/métodos , Titanio
5.
Subst Use Misuse ; 49(13): 1784-94, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25014615

RESUMEN

BACKGROUND: Baseline patients' characteristics are critical for treatment planning, as these can be moderators of treatment effects. In Mexico, information on treatment seekers with substance use disorders is scarce and limited to demographic characteristics. OBJECTIVE: This paper presents and analyses demographic characteristics, substance use related problems, clinical features, and addiction severity in a sample of treatment seekers from the first multi-site randomized clinical trial implemented in the Mexican Clinical Trials Network on Addiction and Mental Health. METHODS: A total of 120 participants were assessed prior randomization. Chi square or F-tests were used to compare sites across variables. Spearman correlation was used to associate negative consequences of substance use and motivation to change. RESULTS: The majority of participants were men, and the most prevalent substances reported were alcohol, marijuana, and cocaine. Participants were predominantly on the contemplation or action stage of change, and this was correlated with the perception of the negative consequences associated with substance use. Participants reported a high prevalence of substance use related problems. CONCLUSIONS: Substance use related problems, clinical features, and addiction severity reported by treatment seekers are important characteristics to take into account when planning treatment as they facilitate tailoring treatment to meet patients' needs.


Asunto(s)
Aceptación de la Atención de Salud/estadística & datos numéricos , Centros de Tratamiento de Abuso de Sustancias/estadística & datos numéricos , Trastornos Relacionados con Sustancias/terapia , Adulto , Alcoholismo/epidemiología , Alcoholismo/psicología , Alcoholismo/terapia , Trastornos Relacionados con Cocaína/epidemiología , Trastornos Relacionados con Cocaína/psicología , Trastornos Relacionados con Cocaína/terapia , Femenino , Humanos , Masculino , Abuso de Marihuana/epidemiología , Abuso de Marihuana/psicología , Abuso de Marihuana/terapia , México/epidemiología , Motivación , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/psicología
6.
Biomed Mater Eng ; 21(5-6): 323-32, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22561251

RESUMEN

Some of the current clinical and biomechanical data suggest that vertebroplasty causes the development of adjacent vertebral fractures shortly after augmentation. These findings have been attributed to high injection volumes as well as high Young's moduli of PMMA bone cements compared to that of the osteoporotic cancellous bone. The aim of this study was to evaluate the use of castor oil as a plasticizer for PMMA bone cements. The Young's modulus, yield strength, maximum polymerization temperature, doughing time, setting time and the complex viscosity curves during curing, were determined. The cytotoxicity of the materials extracts was assessed on cells of an osteoblast-like cell line. The addition of up to 12 wt% castor oil decreased yield strength from 88 to 15 MPa, Young's modulus from 1500 to 446 MPa and maximum polymerization temperature from 41.3 to 25.6°C, without affecting the setting time. However, castor oil seemed to interfere with the polymerization reaction, giving a negative effect on cell viability in a worst-case scenario.


Asunto(s)
Cementos para Huesos/química , Aceite de Ricino/farmacología , Materiales Biocompatibles Revestidos/química , Módulo de Elasticidad/efectos de los fármacos , Polimetil Metacrilato/química , Cementos para Huesos/síntesis química , Cementos para Huesos/farmacología , Aceite de Ricino/química , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/farmacología , Fuerza Compresiva/efectos de los fármacos , Módulo de Elasticidad/fisiología , Humanos , Ensayo de Materiales , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoblastos/fisiología , Plastificantes/química , Plastificantes/farmacología , Polimetil Metacrilato/farmacología , Propiedades de Superficie/efectos de los fármacos
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