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1.
Appl Mater Today ; 32: 101828, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37317691

RESUMO

Commercial polyurethane (PU) coating formulations have been modified with 1-(hydroxymethyl)-5,5-dimethylhydantoin (HMD) both in bulk (0.5 and 1% w/w) and onto the coatings surface as an N-halamine precursor, to obtain clear coatings with high virucidal activity. Upon immersion in diluted chlorine bleaching, the hydantoin structure on the grafted PU membranes was transformed into N-halamine groups, with a high surface chlorine concentration (40-43µg/cm2). Fourier transform infrared spectroscopy (FTIR) spectroscopy, thermogravimetric analysis (TGA), energy-dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS) and iodometric titration were used to characterize the coatings and quantify the chlorine contents of the PU membranes after chlorination. Biological evaluation of their activity against Staphylococcus aureus (Gram-positive bacteria) and human coronaviruses HCoV-229E and SARS-CoV-2 was performed, and high inactivation of these pathogens was observed after short contact times. The inactivation of HCoV-229E was higher than 98% for all modified samples after just 30 minutes, whereas it was necessary 12 hours of contact time for complete inactivation of SARS-CoV-2. The coatings were fully rechargeable by immersion in diluted chlorine bleach (2% v/v) for at least 5 chlorination-dechlorination cycles. Moreover, the performance of the antivirus efficiency of the coatings is considered as long-lasting, because experiments of reinfection of the coatings with HCoV-229E coronavirus did not show any loss of the virucidal activity after three consecutive infection cycles without reactivation of the N-halamine groups.

2.
Polymers (Basel) ; 14(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36365703

RESUMO

Every year millions of people worldwide undergo surgical interventions, with the occurrence of mild or severe post-treatment consequences meaning that rehabilitation plays a key role in modern medicine. Considering the cases of burns and plastic surgery, the pressing need for new materials that can be used for wound patches or body fillers and are able to sustain tissue regeneration and promote cell adhesion and proliferation is clear. The challenges facing next-generation implant materials also include the need for improved structural properties for cellular organization and morphogenic guidance together with optimal mechanical, rheological, and topographical behavior. Herein, we propose for the first time a sodium alginate hydrogel obtained by a thiol-yne reaction, easily synthesized using carbodiimide chemistry in a two-step reaction. The hydrogels were formed in all cases within a few minutes of light irradiation, showing good self-standing properties under solicitation. The mechanical, rheological, topographical, and swelling properties of the gels were also tested and reported. Lastly, no cytotoxicity was detected among the hydrogels. Soluble extracts in culture media allowed cell proliferation, and no differences between samples were detected in terms of metabolic activity and DNA content. These results suggest the potential use of these cytocompatible hydrogels in tissue engineering and regenerative medicine.

3.
Rev. argent. reumatolg. (En línea) ; 32(4): 12-20, dic. 2021. tab
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1376439

RESUMO

Introducción: las limitaciones laborales son un punto importante a considerar en el tratamiento de la espondiloartritis axial (EspAax) dado que esta enfermedad afecta a las personas en la etapa más productiva de la vida. Objetivos: describir la situación laboral en pacientes con EspAax de Argentina, incluyendo la espondilitis anquilosante (EA) y la espondiloartritis axial no radiográfica (EspAax-nr), y evaluar los factores asociados a la pérdida de productividad laboral (PPL) en esta cohorte nacional y los factores asociados a estar empleado. Materiales y métodos: en este estudio transversal y multicéntrico se incluyeron pacientes con diagnóstico de EA y EspAax-nr según los criterios de clasificación de la Assessment of SpondyloArthritis international Society (ASAS 2009) y en edad laboral (≤65 años). Los objetivos principales fueron evaluar la situación laboral, el ausentismo y el presentismo, valorados por el cuestionario Work Productivity and Activity Impairment Spondyloarthritis (WPAI-SpA). Se utilizó el coeficiente de Spearman para evaluar la correlación entre las medidas de la enfermedad y la PPL. Se realizó un análisis bivariado y multivariado para evaluar los factores asociados a estar empleado. Resultados: se incluyeron 129 pacientes con EspAax, 95 (73,6 %) con EA y 34 (26,4%) con EspAax-nr. La mediana (p25-75) de edad fue de 45 (35-55) años. La duración mediana de la enfermedad fue de 62 (24-123) meses y el retraso en el diagnóstico fue de 24 (6-72) meses. Sesenta (46,5%) pacientes estaban empleados. La mediana (p25-75) de presentismo de los pacientes con EA fue del 29,6% (0-57) y del 30% (20-40) para los pacientes con EspAax-nr (p=0,02). Asimismo, la mediana (p25-75) de PPL fue del 30% en ambos grupos de pacientes. Se encontró una correlación positiva entre la PPL y las siguientes variables: ASDAS (Rho:0.60), BASDAI (Rho:0.50), BASFI (Rho:0.60), ASQoL (Rho:0.60) y ASAS health index (Rho:0.54). En el análisis bivariado, los factores asociados al desempleo fueron el diagnóstico de EA, la edad avanzada, la mayor duración de la enfermedad, las comorbilidades (hipertensión y diabetes), el menor número de años de educación, la peor calidad de vida y la menor capacidad funcional. En el análisis multivariado, una mejor función física (evaluada por BASFI) se asoció de forma independiente a estar empleado. Conclusiones: este estudio demostró que la PPL en esta cohorte nacional fue del 30% en la EspAax. Se asoció con la actividad de la enfermedad, el estado de salud, la calidad de vida y la capacidad funcional. Una mejor función física se relacionó en forma independiente con una mayor probabilidad de mantener a los pacientes con EspAax empleados.


Introduction: work disability is an important outcome in the treatment of spondyloarthritis (SpA) since this disease affects people in the most productive stage of life. Objectives: to investigate working status in patients with axial spondyloarthritis (axSpA) from Argentina, including ankylosing spondylitis (AS) and nonradiographic axial SpA (nr-axSpA), and to evaluate factors associated with work productivity loss (WPL) in this national cohort and factors associated with being employed. Materials and methods: patients with a diagnosis of AS and nr-axSpA according to Assessment of SpondyloArthritis international Society (ASAS 2009) classification criteria and in working age (≤65 years) were included in this multicentric cross-sectional study. Outcomes of interest were employment status, absenteeism and presenteeism, assessed by the Work Productivity and Activity Impairment Spondyloarthritis (WPAI-SpA) questionnaire. Spearman's coefficient was used to assess the correlation between disease measures and WPL. Bivariate and multivariate analysis were performed in order to evaluate factors associated with being employed. Results: 129 patients with axSpA were included, 95 (73.6%) with AS and 34 (26.4%) with nr-axSpA. Median (p25-75) age of 45 (35-55) years. Median (p25-75) disease duration was 62 (24-123) months and diagnosis delay was 24 (6-72) months. 60 (46.5%) of the patients were employed. Median (p25-75) presenteeism of AS patients was 29.6% (0-57) and 30% (20-40) for patients with EspAax-nr (p=0.02). Median (p25-75) WPL was 30% in both groups of patients. A positive correlation was found between WPL and the following variables: ASDAS (Rho:0.60), BASDAI (Rho:0.50), BASFI (Rho:0.60), ASQoL (Rho:0.60) and ASAS health index (Rho:0.54). In the bivariate analysis, the factors associated with unemployment were AS diagnosis, older age, longer disease duration, comorbidities (hypertension and diabetes), fewer years of education, worse quality of life and lower functional capacity. In the multivariate analysis, better physical function (assessed by BASFI) was independently associated with being employed. Conclusions: this study showed that WPL in this national cohort was 30% in axSpA. It was associated with disease activity, health status, quality of life and functional capacity. Better physical function was independently associated with a higher likelihood of keeping patients with axSpA employed.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Espondiloartrite Axial/epidemiologia , Doenças Profissionais/epidemiologia , Qualidade de Vida , Fatores Socioeconômicos , Modelos Logísticos , Nível de Saúde , Estudos Transversais , Estudos de Coortes , Absenteísmo , Eficiência , Presenteísmo , Espondiloartrite Axial/etiologia , Espondiloartrite Axial não Radiográfica/etiologia , Espondiloartrite Axial não Radiográfica/epidemiologia
4.
Materials (Basel) ; 13(20)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066584

RESUMO

Two new copper complexes of hyperbranched polymers modified with dansyl units were synthesized and characterized by infrared spectroscopy (IR) and electron paramagnetic resonance (EPR) techniques. It was found that copper ions coordinate predominantly with nitrogen or oxygen atoms of the polymer molecule. The place of the formation of complexes and the number of copper ions involved depend on the chemical structure of the polymer. The antimicrobial activity of the new polymers and their Cu(II) complexes was tested against Gram-negative and Gram-positive bacterial and fungal strains. Copper complexes were found to have activity better than that of the corresponding ligands. The deposition of the modified branched polymers onto cotton fabrics prevents the formation of bacterial biofilms, which indicates that the studied polymers can find application in antibacterial textiles.

5.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1125864

RESUMO

Las Miopatías Inflamatorias Autoinmunes (MI) comprenden un grupo de enfermedades heterogéneas con presentación y características clínicas variables. Se distinguen subtipos clínicos como Polimiositis (PM), Dermatomiositis (DM), Miositis por cuerpos de Inclusión (MCI), Miopatía Necrotizante Inmunomediada (MNIM), Miositis de los Síndromes de Superposición, formas juveniles de MI (DMJ), Síndrome Antisintetasa (SAS) y Miopatía Asociada a Cáncer (MAC). La presencia de anticuerpos séricos y el infiltrado inflamatorio en la biopsia de músculo sugiere que se trata de una condición autoinmune. Realizar el diagnóstico de las MI suele ser un desafío y las herramientas diagnósticas no siempre están disponibles en la práctica diaria. Se obtuvo información sobre la disponibilidad de estos métodos del Registro Argentino de Miopatías Inflamatorias. El estudio de enzimas musculares, Anticuerpos Antinucleares (ANA), anticuerpo anti-Jo-1 y la tomografía computada de tórax, estuvieron disponibles para la mayoría de los pacientes mientras que la Resonancia Magnética de musculo (RM), el estudio de difusión de monóxido de carbono (DLco) y la biopsia muscular se realizaron en menos del 50% de los casos. La determinación de otros anticuerpos específicos de miositis, de importancia en el diagnóstico y pronóstico de la enfermedad se realizó, en mayor parte, a través de un subsidio de la SAR.


The Idiopathic Inflammatory Myopathies (IIM) comprise a heterogeneous group of acquired muscle diseases classified as polymyositis (PM), dermatomyositis (DM), Inclusion Body Myositis (IBM), Immuno Mediated Necrotizing Myopathies (IMNM), Overlap Myositis (OM), juvenile myositis, Antisynthethase Syndrome (ASS) and cancer related myositis (CAM). The presence of myositis specific antibodies in the serum and autoantibodies against target antigens and inflammatory infiltrates in muscle tissue suggests the autoimmune condition of the disease. The diagnosis of inflammatory myopathies is often a challenge and the disposal of diagnostic tools are not always available in daily practice. Information on the accessibility of these methods was obtained from the Argentine Register of Myopathies. The study of muscle enzymes, ANA, anti-Jo-1 antibodies and chest tomography were easy to get to most patients while muscle MRI, lung diffusion capacity for carbon monoxide (DLco) and muscle biopsy were performed in less than 50% of cases. Other myositis specific antibodies, necessary for disease diagnosis and prognosis, were mostly done through a subsidy from the Argentine Rheumatology Society.


Assuntos
Doenças Musculares , Reumatologia , Diagnóstico , Anticorpos
6.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1123717

RESUMO

Las Miopatías Inflamatorias Autoinmunes (MI) comprenden un grupo de enfermedades heterogéneas con presentación y características clínicas variables. Se distinguen subtipos clínicos como Polimiositis (PM), Dermatomiositis (DM), Miositis por cuerpos de Inclusión (MCI), Miopatía Necrotizante Inmunomediada (MNIM), Miositis de los Síndromes de Superposición, formas juveniles de MI (DMJ), Síndrome Antisintetasa (SAS) y Miopatía Asociada a Cáncer (MAC).La presencia de anticuerpos séricos y el infiltrado inflamatorio en la biopsia de músculo sugiere que se trata de una condición autoinmune. Realizar el diagnóstico de las MI suele ser un desafío y las herramientas diagnósticas no siempre están disponibles en la práctica diaria. Se obtuvo información sobre la disponibilidad de estos métodos del Registro Argentino de Miopatías Inflamatorias. El estudio de enzimas musculares, Anticuerpos Antinucleares (ANA), anticuerpo anti-Jo-1 y la tomografía computada de tórax, estuvieron disponibles para la mayoría de los pacientes mientras que la Resonancia Magnética de musculo (RM), el estudio de difusión de monóxido de carbono (DLco) y la biopsia muscular se realizaron en menos del 50% de los casos. La determinación de otros anticuerpos específicos de miositis, de importancia en el diagnóstico y pronóstico de la enfermedad se realizó, en mayor parte, a través de un subsidio de la SAR.


The Idiopathic Inflammatory Myopathies (IIM) comprise a heterogeneous group of acquired muscle diseases classified as polymyositis (PM), dermatomyositis (DM), Inclusion Body Myositis(IBM), ImmunoMediated Necrotizing Myopathies, (IMNM), Overlap Myositis(OM), juvenile myositis, Antisynthethase Syndrome (ASS) and cancer related myositis(CAM).The presence of myositis specific antibodies in the serum and autoantibodies against target antigens and inflammatory infiltrates in muscle tissue suggests the autoimmune condition of the disease. The diagnosis of inflammatory myopathies is often a challenge and the disposal of diagnostic tools are not always available in daily practice. Information on the accessibility of these methods was obtained from the Argentine Register of Myopathies. The study of muscle enzymes, ANA, anti-Jo-1 antibodies and chest tomography were easy to get to most patients while muscle MRI, lung diffusion capacity for carbon monoxide (DLco%) and muscle biopsy were performed in less than 50% of cases. Other myositis specific antibodies, necessary for disease diagnosis and prognosis, were mostly done through a subsidy from the Argentine Rheumatology Society.


Assuntos
Humanos , Doenças Musculares , Reumatologia , Biópsia , Anticorpos
7.
Materials (Basel) ; 12(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540365

RESUMO

A second-generation poly(propylene imine) dendrimer modified with acridine and its Cu(II) complex have been synthesized for the first time. It has been found that two copper ions form complexes with the nitrogen atoms of the dendrimeric core by coordinate bonds. The new compounds have been characterized by nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), fourier-transform infrared spectroscopy (FTIR) and fluorescence spectroscopy. The spectral characteristics of the modified dendrimer have been measured in different organic solvents, and a negative fluorescence solvatochromism has been observed. The antimicrobial activity of the dendrimers has been tested against model pathogenic microorganisms in agar and by broth dilution method. The cotton fabric treated with both dendrimers has been evaluated towards pathogenic microorganisms. The obtained modified cotton fabrics have been shown to hamper bacterial growth and to prevent biofilm formation. Dendrimer cytotoxicity has been investigated in vitro in the model HEp-2 cell line.

8.
ACS Appl Mater Interfaces ; 10(45): 39319-39326, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30346129

RESUMO

In this work, we propose an innovative strategy for obtaining functional objects employing a light-activated three-dimensional (3D) printing process without affecting the materials' printability. In particular, a dye is a necessary ingredient in a formulation for a digital light processing 3D printing method to obtain precise and complex structures. Here, we use a photoluminescent dye specifically synthesized for this purpose that enables the production of 3D printed waveguides and splitters able to guide the luminescence. Moreover, copolymerizing the dye with the polymeric network during the printing process, we are able to maintain the solvatochromic properties of the dye toward different solvents in the printed structures, enabling the development of solvents' polarity sensors.

9.
Acta Biomater ; 6(11): 4189-98, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20561601

RESUMO

Hyperbranched poly(ester amide) polymer (Hybrane S1200, M(n) 1200 gmol(-1)) was functionalized with maleic anhydride (MA) and propylene sulfide, to obtain multifunctional cross-linkers with fumaric and thiol end groups, S1200MA and S1200SH, respectively. The degree of substitution (DS) of maleic acid groups was controlled by varying the molar ratio of MA to S1200 in the reaction mixture. Hydrogels were obtained by UV cross-linking of functionalized S1200 and poly(ethylene glycol) diacrylate in aqueous solutions. Compressive modulus increased with decreasing S1200/PEG ratio and also depended on the DS of the multifunctional cross-linker (S1200). Also, heparin-based macromonomers together with functionalized hyperbranched polymers were used to construct novel functional hydrogels. The multivalent hyperbranched polymers allowed high cross-linking densities in heparin modified gels while introducing biodegradation sites. Both heparin presence and acrylate/thiol ratio had an impact on degradation profiles and morphologies. Hyperbranched cross-linked hydrogels showed no evidence of cell toxicity. Overall, the multifunctional cross-linkers afford hydrogels with promising properties that suggest that these may be suitable for tissue engineering applications.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Reagentes de Ligações Cruzadas/química , Hidrogéis/química , Hidrogéis/síntese química , Heparina/química , Heparina/metabolismo , Microscopia Eletrônica de Varredura , Polietilenoglicóis/química , Fatores de Tempo
10.
Artigo em Inglês | MEDLINE | ID: mdl-20399137

RESUMO

A new dyad containing two 1,8-naphthalimides has been synthesized. N,N-Dimetylaminoethylamino group has been used as substituent at C-4 position of the 1,8-naphthalimide chromophore structure. The photophysical characteristics of the dyad have been investigated in organic solvents with different polarity. In acetonitrile solution the newly synthesized dyad enhance its fluorescent intensity in the presence of metal cations (Ni(2+), Co(2+), Cu(2+), Pb(2)(+), Zn(2+), Fe(3+)) and protons due to quenching of photoinduced electron transfer.


Assuntos
Cátions/análise , Metais/análise , Naftalimidas/química , Espectrometria de Fluorescência/métodos , Naftalimidas/síntese química , Fotoquímica , Prótons
11.
J Fluoresc ; 19(1): 127-39, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18665437

RESUMO

Two highly photostable yellow-green emitting 1,8-naphthalimides 5 and 6, containing both N-linked hindered amine moiety and a secondary or tertiary cation receptor, were synthesized for the first time. Novel compounds were configured as "fluorophore-spacer-receptor" systems based on photoinduced electron transfer. Photophysical characteristics of the dyes were investigated in DMF and water/DMF (4:1, v/v) solution. The ability of the new compounds to detect cations was evaluated by the changes in their fluorescence intensity in the presence of metal ions (Cu2+, Pb2+, Zn2+, Ni2+, Co2+) and protons. The presence of metal ions and protons was found to disallow a photoinduced electron transfer leading to an enhancement in the dye fluorescence intensity. Compound 5, containing secondary amine receptor, displayed a good sensor activity towards metal ions and protons. However the sensor activity of dye 6, containing a tertiary amine receptor and a shorter hydrocarbon spacer, was substantially higher. The results obtained indicate the potential of the novel compounds as highly photostable and efficient "off-on" pH switchers and fluorescent detectors for metal ions with pronounced selectivity towards Cu2+ ions.


Assuntos
Corantes Fluorescentes/síntese química , Metais Pesados/análise , Naftalimidas/síntese química , Prótons , Cátions/análise , Corantes Fluorescentes/química , Estrutura Molecular , Naftalimidas/química , Fotoquímica
12.
Dermatol. pediátr. latinoam. (Impr.) ; 5(2): 130-132, mayo.-ago. 2007. ilus
Artigo em Espanhol | LILACS, InstitutionalDB, BINACIS, UNISALUD | ID: biblio-1362175

RESUMO

La nocardiosis ocurre principalmente como una infección oportunista en adultos inmunocomprometidos; aunque ha sido reportada en pacientes sanos y en niños. Presentamos el caso de un varón de once años, sano, con lesión cutánea de seis meses de evolución a nivel de miembro inferior derecho y muñeca izquierda, sin tratamiento previo, en cuyo cultivo desarrolló Nocardia. Se inició manejo con trimetropin-sulfametoxazol con excelente evolución a los tres meses de tratamiento (AU)


Nocardiosis occurs mainly as an opportunistic infection in immunosuppressed patients, although it has been reported on healthy patients and children.We report an 11-year-old immunocompetent boy with a 6-month history of skin lesion on the rigth leg and left wrist. Skin biopsy and cultures was performed and Nocardia was isolated.Treatment with trimethoprim- sulfamethoxazole was started, achieving significant improvement within 3 months (AU)


Assuntos
Humanos , Masculino , Criança , Nocardiose , Punho , Extremidade Inferior
13.
Chemistry ; 11(15): 4314-25, 2005 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-15812870

RESUMO

Fluorescence spectroscopy is an important analytical technique that has been widely used in a variety of applications, such as biomedicine, biology, and science of materials, because it presents some properties which makes it unique, that is, extraordinary sensitivity and selectivity, short delay time (<10(-9) s), and it is neither invasive nor destructive, so it can be used for in situ measurements. Generally, intrinsic fluorescence of many materials, like polymers, is unspecific so it is not useful to analyse their properties or to be correlated to changes in their microenvironment. The incorporation of additives with fluorescent groups would be necessary. When the fluorescence emission of these molecules is sensitive to changes of properties, such as polarity, fluidity, order, molecular mobility, pH, or electric potential, they can be used for detecting such changes in their microenvironment, and they are called fluorescent probes. As long as these probes can follow processes of practical interest, they can be employed as sensors, if the information given by the measure of fluorescence adequately reflects the changes in the system. In addition, a sensor must fulfil some other requirements in order to make them of practical use, the most important being that the material support in which the sensor molecule is inserted. This support should permit a rapid detection of the process and should allow easy processing in a variety of forms. Polymers are well-known systems in which estimation of local parameters are possible by means of fluorimetric techniques. It allows the study of dynamic processes of interest, such as polymerization kinetics and mechanisms, thermal transitions, photodegradation, swelling morphology changes, and so forth.

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