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1.
J Chem Inf Model ; 64(13): 5127-5139, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38888100

ABSTRACT

Molecularly imprinted polymers (MIPs) have emerged as bespoke materials with versatile molecular applications. In this study, we propose a proof of concept for a methodology employing molecular dynamics (MD) simulations to guide the selection of functional monomers for curcuminoid binding in MIPs. Curcumin, demethoxycurcumin, and bisdemethoxycurcumin are phenolic compounds widely employed as spices, pigments, additives, and therapeutic agents, representing the three main curcuminoids of interest. Through MD simulations, we investigated prepolymerization mixtures composed of various functional monomers, including acrylamide (ACA), acrylic acid (AA), methacrylic acid (MAA), and N-vinylpyrrolidone (NVP), with ethylene glycol dimethacrylate (EGDMA) as the cross-linker and acetonitrile as the solvent. Curcumin was selected as the template molecule due to its structural similarity to the other curcuminoids. Notably, the prepolymerization mixture containing NVP as the functional monomer demonstrated superior molecular recognition capabilities toward curcumin. This observation was supported by higher functional monomer molecules surrounding the template, a lower total nonbonded energy between the template and monomer, and a greater number of hydrogen bonds in the aggregate. These findings suggest a stronger affinity between the functional monomer NVP and the template. We synthesized, characterized, and conducted binding tests on the MIPs to validate the MD simulation results. The experimental binding tests confirmed that the MIP-NVP exhibited higher binding capacity. Consequently, based on MD simulations, our computational methodology effectively guided the selection of the functional monomer, leading to MIPs with binding capacity for curcuminoids. The outcomes of this study provide a valuable reference for the rational design of MIPs through MD simulations, facilitating the selection of components for MIPs. This computational approach holds the potential for extension to other templates, establishing a robust methodology for the rational design of MIPs.


Subject(s)
Curcumin , Molecular Dynamics Simulation , Molecularly Imprinted Polymers , Curcumin/chemistry , Curcumin/analogs & derivatives , Curcumin/metabolism , Molecularly Imprinted Polymers/chemistry , Drug Design , Molecular Imprinting , Methacrylates/chemistry , Diarylheptanoids/chemistry , Molecular Conformation
2.
ACS Omega ; 9(1): 204-214, 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38222599

ABSTRACT

Polymeric coatings are a promising option for the development of delivery systems for orally administered drugs. However, the gastrointestinal conditions to which they are subjected, which include low pH and solubility as well as peristaltic movements, can limit their applications. In this work, different formulations of polymeric coatings were produced using pH-sensitive materials consisting of copolymers of methyl acrylate, methyl methacrylate, and methacrylic acid. The polymers were synthesized by the emulsion polymerization technique, obtaining small average particle sizes (56-190 nm), molecular weights between 200,000 and 400,000 g/mol, and a glass transition temperature above 35 °C, which are suitable for film formation at room temperature. Thus, they were assessed as coatings for hydroxypropyl methylcellulose capsules (HPMC) using the immersion method, showing adequate capacity to protect the capsule at gastric pH (pH 1.2) and dissolve at the simulated intestinal pH (pH= 7.2). In particular, the higher the content of the acidic monomer, the higher the release time of the test molecule contained in the acrylic terpolymer-coated HPMC capsules proposed, which was a curcuminoid derivative due to their bright color and potential medical benefits. In addition, a minimum number of immersions was required for coating the HPMC capsules at high acidic concentrations, which further facilitates the delayed release needed for colonic treatment. However, too high proportions of methacrylic acid may result in cytotoxicity issues. Consequently, a biocompatible formulation containing a proportion of methyl acrylate, methyl methacrylate, and methacrylic acid of 7:3:3 is proposed as the most adequate for colonic release. Thus, by chemically modulating the molar percentages of the acrylic monomers, it was possible to obtain tailored acrylic terpolymer coatings with different characteristics and desired properties in order to modulate the release kinetics of an active substance in a colonic environment.

3.
PLoS One ; 17(6): e0270202, 2022.
Article in English | MEDLINE | ID: mdl-35731741

ABSTRACT

In this paper we present the design of an open-source and low-cost buoy prototype for remote monitoring of water quality variables in fish farming. The designed battery-powered system periodically measures temperature, pH and dissolved oxygen, transmitting the information locally through a low-power wide-area network protocol to a gateway connected to a cloud service for data storage and visualization. We provide a novel buoy design that can be easily constructed with off-the-shelf materials, delivering a stable anchored float for the IoT device and the probes immersed in the water pond. The prototype was tested at an operating fish farm, showing promising results for a low-cost remote monitoring tool that enables automatic data acquisition and storage in fish farming scenarios. All the elements of this design, including hardware and software designs, are freely available under permissive licenses as an open-source project.


Subject(s)
Fisheries , Water Quality , Cloud Computing
4.
Anal Chim Acta ; 953: 23-31, 2017 Feb 08.
Article in English | MEDLINE | ID: mdl-28010739

ABSTRACT

Montmorillonite (MMT) clays were modified by the intercalation into their galleries of ionic liquids (IL) based on imidazolium quaternary ammonium salts. This new eco-materials exhibited good features for use as a sorptive phase in the extraction of low-polarity analytes from aqueous samples. Spectroscopic analyses of the modified clays were conducted and revealed an increase in the basal spacing and a shifting of the reflection plane towards lower values as a consequence of the effective intercalation of organic cations into the MMT structure. The novel sorbent developed herein was assayed as the sorptive phase in rotating-disk sorptive extraction (RDSE), using polychlorinated biphenyls (PCBs), representative of low-polarity pollutants, as model analytes. The final determination was made by gas chromatography with electron capture detection. Among the synthetized sorptive phases, the selected system for analytical purposes consisted of MMT modified with the 1-hexadecyl-3-methylimidazolium bromide (HDMIM-Br) IL. Satisfactory analytical features were achieved using a sample volume of 5 mL: the relative recoveries from a wastewater sample were higher than 80%, the detection limits were between 3 ng L-1 and 43 ng L-1, the precision (within-run precision) expressed as the relative standard deviation ranged from 2% to 24%, and the enrichment factors ranged between 18 and 28. Using RDSE, the extraction efficiency achieved for the selected MMT-HDMIM-Br phase was compared with other commercial solid phases/supports, such as polypropylene, polypropylene with 1-octanol (as a supported liquid membrane), octadecyl (C18) and octyl (C8), and showed the highest response for all the studied analytes. Under the optimized extraction conditions, this new device was applied in the analysis of the influent of a wastewater treatment plant in Santiago (Chile), demonstrating its applicability through the good recoveries and precision achieved with real samples.

5.
Rev. MED ; 24(1): 89-96, ene.-jun. 2016. ilus, tab
Article in Spanish | LILACS | ID: biblio-957286

ABSTRACT

Trichosporon asahii es un hongo patógeno emergente reportado en la literatura médica principalmente en pacientes inmunocomprometidos. No obstante, el presente caso es inusual debido a que se trata de un paciente adulto joven inmunocompetente que presentó fungemia por T. asahii y al mismo tiempo desarrolló insuficiencia respiratoria aguda por bronquiolitis respiratoria y neumonía descamativa, la cual resolvió posterior al tratamiento antimicótico instaurado, soporte ventilatorio y vigilancia en Unidad de Cuidado Intesivo (UCI).


Trichosporon asahii is an emerging fungal pathogen reported in the medical literature mainly in immunologically compromised patients. However, this case is unusual because is a young immunocompetent patient who developed fungemia by T. asahii simultaneously with acute respiratory failure, respiratory bronchiolitis and desquamative interstitial pneumonia, who responded satisfactorily to ventilatory support and antifungal therapy.


Trichosporon asahii é um patógeno fúngico emergente relatado na literatura médica principalmente em pacientes imunologicamente comprometidos. No entanto, este caso é incomum porque é um jovem imunocompetente que desenvolveu fungemia por T. asahii simultaneamente com insuficiência respiratória aguda, bronquiolite respiratória e pneumonia intersticial descamativa, que responderam satisfatoriamente ao suporte ventilatório e à terapia antifúngica.


Subject(s)
Humans , Male , Adult , Immunocompetence , Pneumonia , Trichosporon , Fungemia
6.
Dent Mater ; 31(7): 789-98, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25931142

ABSTRACT

OBJECTIVE: The aim of this work was to study the effect of silica nanoclusters (SiNC), obtained by a solvent evaporation method and functionalized by 3-methacryloxypropyltrimethoxysilane (MPS) and MPS+octyltrimethoxysilane (OTMS) (50/50wt/wt), on the rheological, mechanical and sorption properties of urethane dimethylacrylate (UDMA)/triethylenglycol dimethacrylate (TEGDMA) (80/20wt/wt) resins blend. METHODS: Silica nanoparticles (SiNP) were silanized with MPS or MPS+OTMS (50/50wt/wt) and incorporated in an UDMA-isopropanol mix to produce functionalized silica nanoclusters after evaporating the isopropanol. The effect of functionalized SiNC on resins rheological properties was determined by large and small deformation tests. Mechanical, thermal, sorption and solubility properties were evaluated for composite materials. RESULTS: The UDMA/TEGDMA (80/20wt/wt) resins blend with added SiNC (ca. 350nm) and functionalized with MPS showed a Newtonian flow behavior associated to their spheroidal shape, whereas the resins blend with nanoclusters silanized with MPS+OTMS (50/50wt/wt) (ca. 400nm) showed a shear-thinning behavior due to nanoclusters irregular shape. Composite materials prepared with bare silica nanoclusters showed lower compressive strength than functionalized silica nanoclusters. MPS functionalized nanoclusters showed better mechanical properties but higher water sorption than functionalized nanoclusters with both silane coupling agents, MPS and OTMS. SIGNIFICANCE: The solvent evaporation method applied to functionalized nanoparticles showed to be an alternative way to the sinterization method for producing nanoclusters, which improved some dental composite mechanical properties and reduced water sorption. The shape of functionalized silica nanoclusters showed to have influence on the rheological properties of SiNC resin suspensions and the mechanical and sorption properties of light cured composites.


Subject(s)
Composite Resins/chemistry , Nanocomposites/chemistry , Nanoparticles/chemistry , Elastic Modulus , Materials Testing , Methacrylates/chemistry , Microscopy, Electron , Molecular Structure , Polyethylene Glycols/chemistry , Polymethacrylic Acids/chemistry , Polyurethanes/chemistry , Silanes/chemistry , Silicon Dioxide/chemistry , Solvents/chemistry , Spectroscopy, Fourier Transform Infrared , Viscosity
7.
Biomedica ; 33(1): 28-30, 2013.
Article in Spanish | MEDLINE | ID: mdl-23715303

ABSTRACT

This article presents the case of a young woman with massive hemoptysis (1,000 mL in 6 hours) due to tuberculosis, which could not be controlled by insertion of a Fogarty catheter through a fiber-optic bronchoscope. Because of asphyxia and persistent bleeding risk we instilled fibrinogen-thrombin through a fiber-optic bronchoscope inserted catheter, achieving bleeding cessation and permitting the placing of a double-lumen oro-tracheal tube. Later on, the patient underwent lobectomy and anti-tuberculosis treatment. The fibrinogen-thrombin could be considered as a bridge, transitory measure for massive hemoptysis, while definitive treatment could be established.


Subject(s)
Aprotinin/therapeutic use , Factor XIII/therapeutic use , Fibrin Tissue Adhesive/therapeutic use , Fibrinogen/therapeutic use , Hemoptysis/therapy , Hemostatic Techniques , Thrombin/therapeutic use , Adult , Antitubercular Agents/therapeutic use , Aprotinin/administration & dosage , Balloon Occlusion , Bronchoscopy/methods , Catheters , Cholangiopancreatography, Endoscopic Retrograde/instrumentation , Combined Modality Therapy , Drug Combinations , Emergencies , Factor XIII/administration & dosage , Female , Fiber Optic Technology , Fibrin Tissue Adhesive/administration & dosage , Fibrinogen/administration & dosage , Hemoptysis/etiology , Hemoptysis/surgery , Hemostatic Techniques/instrumentation , Humans , Intubation, Intratracheal/instrumentation , Pneumonectomy , Thrombin/administration & dosage , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/surgery
8.
Biomédica (Bogotá) ; Biomédica (Bogotá);33(1): 28-33, ene.-mar. 2013.
Article in Spanish | LILACS | ID: lil-675128

ABSTRACT

Se presenta el caso de una paciente joven con hemoptisis masiva por tuberculosis que no pudo ser controlada de forma efectiva con la inserción de un catéter Fogarty por un fibrobroncoscopio. Ante esto y el alto riesgo de asfixia o desangramiento, se decidió infundir fibrinógeno-trombina a través de un catéter, introducido por el fibrobroncoscopio; con esto se logró controlar el sangrado, intubarla con un tubo orotraqueal de doble luz y estabilizarla para remitirla a otra institución, donde fue sometida a lobectomía y se le proporcionó tratamiento antituberculoso. La infusión de fibrinógeno-trombina podría considerarse como una opción terapéutica transitoria, de tipo puente, mientras se practica el manejo definitivo.


This article presents the case of a young woman with massive hemoptysis (1,000 mL in 6 hours) due to tuberculosis, which could not be controlled by insertion of a Fogarty catheter through a fiber-optic bronchoscope. Because of asphyxia and persistent bleeding risk we instilled fibrinogen-thrombin through a fiber-optic bronchoscope inserted catheter, achieving bleeding cessation and permitting the placing of a double-lumen oro-tracheal tube. Later on, the patient underwent lobectomy and anti-tuberculosis treatment. The fibrinogen-thrombin could be considered as a bridge, transitory measure for massive hemoptysis, while definitive treatment could be established.


Subject(s)
Adult , Female , Humans , Aprotinin/therapeutic use , Factor XIII/therapeutic use , Fibrin Tissue Adhesive/therapeutic use , Fibrinogen/therapeutic use , Hemostatic Techniques , Hemoptysis/therapy , Thrombin/therapeutic use , Antitubercular Agents/therapeutic use , Aprotinin/administration & dosage , Balloon Occlusion , Bronchoscopy/methods , Catheters , Combined Modality Therapy , Cholangiopancreatography, Endoscopic Retrograde/instrumentation , Drug Combinations , Emergencies , Fiber Optic Technology , Factor XIII/administration & dosage , Fibrin Tissue Adhesive/administration & dosage , Fibrinogen/administration & dosage , Hemoptysis/etiology , Hemoptysis/surgery , Hemostatic Techniques/instrumentation , Intubation, Intratracheal/instrumentation , Pneumonectomy , Thrombin/administration & dosage , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/surgery
9.
Adicciones ; 24(1): 69-75, 2012.
Article in Spanish | MEDLINE | ID: mdl-22508019

ABSTRACT

Assessment of a methadone substitution and maintenance treatment program in Colombia using the OTI (Opiate Treatment Index) instrument. Descriptive study with a 50-patient sample attended in the period 2007- 2008 for their heroin addiction. The OTI instrument was implemented to assess drug use, HIV risk-taking behavior, social functioning, criminality, health status and psychological functioning. Men accounted for 74% of the sample, women for 26%. Mean age was 22, with 64% in the 20-24 age group. Mean reported age at onset of heroin use was 18, with a range of 13-28. In 38% of the sample (19 patients) comorbidity with other mental disorders was found, 47% of these being personality disorders. Median reported current methadone dose was 40 mg/day, with a range of 15-80 mg/day. According to the OTI subscales, HIV risk-taking behavior was low-moderate, while social functioning, criminality and health status were low-risk. In the case of psychological adjustment, a low-moderate risk score was obtained for the 0-12 month treatment group, and a moderate risk score for the 12-24 and ≥ 24 month groups. Starting age for heroin use in this population is early . In general, the risk assessed in the OTI areas is low, possibly due to problematic heroin use being in its early stages in Colombia, but comorbidity with personality disorders is high.


Subject(s)
Heroin Dependence/drug therapy , Methadone/therapeutic use , Narcotics/therapeutic use , Opiate Substitution Treatment , Colombia , Female , Humans , Male , Program Evaluation , Young Adult
10.
J Nanosci Nanotechnol ; 8(6): 3176-83, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18681065

ABSTRACT

While carbon nanotubes have been used for a variety of purposes, it was not known whether they can improve tribological properties of polymers. Polyamide 6 (PA6) has been reinforced with 0.2, 0.5 and 1.0 wt% of multiwall carbon nanotubes (MWCNTs) by melt mixing process and characterized by scanning electron microscopy (SEM), transmission electron microscopy, thermogravimetric analysis (TGA), scratching, sliding wear and tensile testing. TGA results for the air atmosphere show that MWCNTs shift the onset of thermal degradation to higher temperatures. Sliding wear tests show that the penetration depth decreases as the concentration of carbon nanotubes increases. However, the viscoelastic healing is hampered by the MWCNTs presence and the residual depths increase at the same time. Narrower scratch groove widths are seen in SEM for composites with MWCNTs, and scratch hardness increases. Tensile tests show an increase of 27% in the Young modulus value upon addition of 1.0% of MWCNTs. The stress at yield is also higher for the nanocomposites.

11.
Ing. sanit. ambient ; (92): 48-53, mayo-jun. 2007. ilus
Article in Spanish | BINACIS | ID: biblio-1163283

ABSTRACT

El objetivo del trabajo consistió en diseñar un sistema de electrocoagulación para el tratamiento de aguas residuales. Con base en la caracterización fisicoquimica de las aguas residuales de una industria lactea, se diseño un sistema de electrocuagulación para estudiar el comportamiento, de los diferentes parámetros involucrados en la remoción de contaminantes de estas aguas. La investigación permitió establecer la geometria tanto de la celda como de los electrodos, materiales y tipo de conexión y adicionalmente, determinar los parámetros eléctricos de la fuente de voltaje. Finalmente se diseñó un sistema de electrocoagulación conformada por una celda tipo bach, catodo de hierro y anodo de aluminio conectados en serie con 10 mm de separacion. La fuente de voltaje entrega una corriente máxima de 25 A


Subject(s)
Dairying , Contaminant Removal , Water Purification
12.
Ingeniería sanitaria y ambiental (Buenos Aires) ; (92): 48-53, mayo-jun. 2007. ilus
Article in Spanish | BINACIS | ID: bin-134402

ABSTRACT

El objetivo del trabajo consistió en diseñar un sistema de electrocoagulación para el tratamiento de aguas residuales. Con base en la caracterización fisicoquimica de las aguas residuales de una industria lactea, se diseño un sistema de electrocuagulación para estudiar el comportamiento, de los diferentes parámetros involucrados en la remoción de contaminantes de estas aguas. La investigación permitió establecer la geometria tanto de la celda como de los electrodos, materiales y tipo de conexión y adicionalmente, determinar los parámetros eléctricos de la fuente de voltaje. Finalmente se diseñó un sistema de electrocoagulación conformada por una celda tipo bach, catodo de hierro y anodo de aluminio conectados en serie con 10 mm de separacion. La fuente de voltaje entrega una corriente máxima de 25 A


Subject(s)
Water Purification , Contaminant Removal , Dairying
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