Application of plasma polymerized pyrrole nanoparticles to prevent or reduce de-differentiation of adult rat ventricular cardiomyocytes.

Cardiovascular diseases are the leading cause of death in the world, cell therapies have been shown to recover cardiac function in animal models. Biomaterials used as scaffolds can solve some of the problems that cell therapies currently have, plasma polymerized pyrrole (PPPy) is a biomaterial that has been shown to promote cell adhesion and survival. The present research aimed to study PPPy nanoparticles (PPPyN) interaction with adult rat ventricular cardiomyocytes (ARVC), to explore whether PPPyN could be employed as a nanoscaffold and develop cardiac microtissues. PPPyN with a mean diameter of 330 nm were obtained, the infrared spectrum showed that some pyrrole rings are fragmented and that some fragments of the ring can be dehydrogenated during plasma synthesis, it also showed the presence of amino groups in the structure of PPPyN. PPPyN had a significant impact on the ARVC´s shape, delaying dedifferentiation, necrosis, and apoptosis processes, moreover, the cardiomyocytes formed cell aggregates up to 1.12 mm2 with some aligned cardiomyocytes and generated fibers on its surface similar to cardiac extracellular matrix. PPPyN served as a scaffold for adult ARVC. Our results indicate that PPPyN-scaffold is a biomaterial that could have potential application in cardiac cell therapy (CCT).

Electrospun PCL-protein scaffolds coated by pyrrole plasma polymerization.

Polymeric scaffolds prepared from polycaprolactone (PCL), PCL-collagen and PCL-elastin were prepared by electrospinning. The scaffolds were coated by plasma polymerization of pyrrole doped with iodine, to improve cellular adhesion and fibroblast proliferation. The morphology, composition, and crystalline structure of the scaffolds were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy, small- and wide-angle X-ray scattering, thermogravimetric analysis and differential scanning calorimetry. The scaffold fibers had average diameters between 90 and 330 nm before coating. After coating by plasma polymerization, the average diameters increased to between 290 and 530 nm. The presence of elastin and collagen in the fibers was corroborated by infrared spectroscopy. X-ray scattering measurements show that neither elastin nor collagen form crystals in the fiber, while PCL maintains its crystallinity and is not affected by the plasma treatment. Fibroblast cell cultures in the presence of the scaffolds were characterized by viability assays and SEM. The results show that the scaffolds modified with plasma polymerized pyrrole provide a suitable environment for fibroblast adhesion, growth and viability.

Acute kidney injury: what part do toll-like receptors play?

The innate immune system plays an important role as a first response to tissue injury. This first response is carried out via germline-encoded receptors. Toll-like receptors (TLRs) are the first identified and best studied family of pattern recognition receptors. TLRs are expressed on a variety of cell types, including epithelial cells, endothelia, dendritic cells, monocytes/macrophages, and B- and T-cells. TLRs initiate innate immune responses and concurrently shape the subsequent adaptive immune response. They are sensors of both pathogens, through the exogenous pathogen-associated molecular patterns (PAMPs), and tissue injury, through the endogenous danger-associated molecular patterns (DAMPs). TLR signaling is critical in defending against invading microorganisms; however, sustained receptor activation is also implicated in the pathogenesis of inflammatory diseases. Ischemic kidney injury involves early TLR-driven immunopathology, and the resolution of inflammation is needed for rapid regeneration of injured tubule cells. Notably, the activation of TLRs also has been implicated in epithelial repair. This review focuses on the role of TLRs and their endogenous ligands within the inflammatory response of acute kidney injury.

Cardioimplante autólogo de células madre de médula ósea en territorios miocárdicos necróticos / Cardiac implant autologous bone marrow stem cells in necrotic myocardial territories / Implante de células-tronco cardíacas autólogas da medula óssea em áreas de necrose miocárdica

Introducción. El concepto clásico de que el corazón era un órgano no regenerativo ha cambiado en la actualidad, por el de ser un órgano en regeneración continua, constituyendo una evidencia sólida de que el tejido cardíaco se encuentra en un proceso continuo de crecimiento, muerte y renovación. Material y método. Se protocolizaron doce pacientes desde el 29 de Mayo de 2004 al 30 de Agosto de 2007. Se excluyeron cinco y de los 7 restantes, cinco fueron evaluados. Se extrajeron por punción de la cresta ilíaca de cada paciente en condiciones estériles 60 cm³ de médula ósea, y se obtuvieron por sedimentación células madre que se identificaron por inmunomarcación con anticuerpo monoclonal anti-CD34 en citómetro de flujo.La evaluación de la viabilidad miocárdica pre y post implante se realizó con PET-FDG. Finalizadas las anastomosis, se implantaron las células madre directamente por punción en territorios no viables. Resultados. Se expresan como porcentajes (variables categóricas) y como media con su desvío estándar (variables continuas). Para evaluar significancia en el cambio de la fracción de eyección se utilizó el test de Wilcoxon. Se consideró significativa una p<0,05. De los 15 segmentos no viables, se implantaron 11 (73%) y se recuperaron 4 (36,36%). La fracción de eyección de ventrículo izquierdo media evaluada por SPECT gatillado fue del 30,2±4,9% en el pre procedimiento y del 34,8±9,5% en el post procedimiento, la mejoría fue de 4,6 puntos (p=0,34), el 60% de los pacientes mejoraron. Conclusiones. Hay una relación entre la concentración de CD34+ (que fue baja: 0,76% de media) y la viabilidad miocárdica. La aparición de viabilidad miocárdica en el 36,36% de los segmentos implantados fue el hallazgo más importante. El método demostró ser seguro, efectivo y reproducible. La utilización de PET-FDG en todos los pacientes para evaluación de viabilidad pre y post implante como método gold standard fue evidencia de regeneración tisular.

Introduction. Currently, the classical concept that the heart was a non-regenerative organ has changed, by being an organ in continuous regeneration constitute strong evidence that cardiac tissue is in a continuous process of growth, death and renewal. Materials and methods. Twelve patients were protocolized from May 29, 2004 to August 30, 2007. We excluded five. Of the 7 remaining, five were evaluated by puncturing of the iliac crest from each patient under sterile conditions 60 cm³ extracted bone marrow and stem cells were obtained by sedimentation and identified by immunostaining with anti-CD34 monoclonal antibody in the flow cytometer. The assessment of myocardial viability before and after implantation was performed with PET-FDG. After the completion anastomosis, the stem cells were implanted directly by puncture nonviable territories. Results. They are expressed as percentages (categorical variables) and as mean with standard deviation (continuous variables). To assess significance in changing ejection fraction was used the Wilcoxon test. Was considered significant at p <0.05. We implanted 11 (73%) of the 15 segments non-viable were recovered 4 (36.36%). The ejection fraction of the left ventricle assessed by SPECT triggered average was 30.2 ± 4.9% in the pre procedure and 34.8 ± 9.5% in the post process, the improvement was 4.6 points (p=0.34), 60% of the patients improved. Conclusions. There is a relationship between the concentration of CD34 + (which was low 0.76% on average) and myocardial viability. The appearance of myocardial viability in 36.36% of the implanted segments was the most important finding. The method proved to be safe, effective and reproducible. The use of PET-FDG in all patients for viability assessment before and after implantation as gold standard method was evidence of tissue regeneration.

Introdução.O conceito clássico que o coração era um órgão não regenerativo mudou agora, por ser um órgão em regeneração contínua constituem fortes provas de que o tecido cardíaco é um processo contínuo de crescimento, morte e renovação. Material e método.Doze pacientes foram incluídos em um protocolo de pesquisa a partir de 29 de Maio de 2004 a 30 de Agosto de 2007. Cinco excluídos. Dos restantes sete, cinco foram avaliados por punção da crista ilíaca do paciente em condições estéreis, foram obtidos 60 cm³ de medula óssea. As células-tronco foram recolhidos por sedimentação e identificados por imunomarcação com o anticorpo monoclonal anti-CD34 no citómetro de fluxo. A avaliação da viabilidade miocárdica antes e após a implantação foi realizada com PET- FDG. Após o término das anastomoses, as células-tronco foram implantadas diretamente por punção em territórios não viáveis. Resultados. Eles são expressos como porcentagens (variáveis categóricas) e média com desvio padrão (variáveis contínuas). Para avaliar a importância na mudança de fração de ejeção foi utilizado o teste de Wilcoxon. Considerou-se significante p<0,05. Dos 15 segmentos não viáveis,foram implantados 11 (73%) e quatro (36,36%) foram recuperados. A fração de ejeção do ventrículo esquerdo avaliada pelo SPECT foi de 30,2±4,9% na fase pré e de 34,8±9,5% no processo de pós, a melhoria foi de 4,6 pontos (p=0,34), 60% dos pacientes melhoraram. Conclusões. Existe uma relação entre a concentração de células CD34+ (baixa: 0,76 %, em média) e a viabilidade do miocárdio. A incidência da viabilidade do miocárdio em 36,36% dos segmentos implantados foi o achado mais importante. O método demonstrou ser seguro, eficaz e reprodutível. O uso de PET-FDG em todos os pacientes para avaliação de viabilidade, antes e depois da implantação como método padrão-ouro, foi evidência de regeneração de tecidos.

Cardioimplante autólogo de células madre de médula ósea en territorios miocárdicos necróticos / Cardiac implant autologous bone marrow stem cells in necrotic myocardial territories / Implante de células-tronco cardíacas autólogas da medula óssea em áreas de necrose miocárdica

Introducción. El concepto clásico de que el corazón era un órgano no regenerativo ha cambiado en la actualidad, por el de ser un órgano en regeneración continua, constituyendo una evidencia sólida de que el tejido cardíaco se encuentra en un proceso continuo de crecimiento, muerte y renovación. Material y método. Se protocolizaron doce pacientes desde el 29 de Mayo de 2004 al 30 de Agosto de 2007. Se excluyeron cinco y de los 7 restantes, cinco fueron evaluados. Se extrajeron por punción de la cresta ilíaca de cada paciente en condiciones estériles 60 cm³ de médula ósea, y se obtuvieron por sedimentación células madre que se identificaron por inmunomarcación con anticuerpo monoclonal anti-CD34 en citómetro de flujo.La evaluación de la viabilidad miocárdica pre y post implante se realizó con PET-FDG. Finalizadas las anastomosis, se implantaron las células madre directamente por punción en territorios no viables. Resultados. Se expresan como porcentajes (variables categóricas) y como media con su desvío estándar (variables continuas). Para evaluar significancia en el cambio de la fracción de eyección se utilizó el test de Wilcoxon. Se consideró significativa una p<0,05. De los 15 segmentos no viables, se implantaron 11 (73%) y se recuperaron 4 (36,36%). La fracción de eyección de ventrículo izquierdo media evaluada por SPECT gatillado fue del 30,2±4,9% en el pre procedimiento y del 34,8±9,5% en el post procedimiento, la mejoría fue de 4,6 puntos (p=0,34), el 60% de los pacientes mejoraron. Conclusiones. Hay una relación entre la concentración de CD34+ (que fue baja: 0,76% de media) y la viabilidad miocárdica. La aparición de viabilidad miocárdica en el 36,36% de los segmentos implantados fue el hallazgo más importante. El método demostró ser seguro, efectivo y reproducible. La utilización de PET-FDG en todos los pacientes para evaluación de viabilidad pre y post implante como método gold standard fue evidencia de regeneración tisular.(AU)

Introduction. Currently, the classical concept that the heart was a non-regenerative organ has changed, by being an organ in continuous regeneration constitute strong evidence that cardiac tissue is in a continuous process of growth, death and renewal. Materials and methods. Twelve patients were protocolized from May 29, 2004 to August 30, 2007. We excluded five. Of the 7 remaining, five were evaluated by puncturing of the iliac crest from each patient under sterile conditions 60 cm³ extracted bone marrow and stem cells were obtained by sedimentation and identified by immunostaining with anti-CD34 monoclonal antibody in the flow cytometer. The assessment of myocardial viability before and after implantation was performed with PET-FDG. After the completion anastomosis, the stem cells were implanted directly by puncture nonviable territories. Results. They are expressed as percentages (categorical variables) and as mean with standard deviation (continuous variables). To assess significance in changing ejection fraction was used the Wilcoxon test. Was considered significant at p <0.05. We implanted 11 (73%) of the 15 segments non-viable were recovered 4 (36.36%). The ejection fraction of the left ventricle assessed by SPECT triggered average was 30.2 ± 4.9% in the pre procedure and 34.8 ± 9.5% in the post process, the improvement was 4.6 points (p=0.34), 60% of the patients improved. Conclusions. There is a relationship between the concentration of CD34 + (which was low 0.76% on average) and myocardial viability. The appearance of myocardial viability in 36.36% of the implanted segments was the most important finding. The method proved to be safe, effective and reproducible. The use of PET-FDG in all patients for viability assessment before and after implantation as gold standard method was evidence of tissue regeneration.(AU)

IntroduþÒo.O conceito clássico que o coraþÒo era um órgÒo nÒo regenerativo mudou agora, por ser um órgÒo em regeneraþÒo contínua constituem fortes provas de que o tecido cardíaco é um processo contínuo de crescimento, morte e renovaþÒo. Material e método.Doze pacientes foram incluídos em um protocolo de pesquisa a partir de 29 de Maio de 2004 a 30 de Agosto de 2007. Cinco excluídos. Dos restantes sete, cinco foram avaliados por punþÒo da crista ilíaca do paciente em condiþ§es estéreis, foram obtidos 60 cm³ de medula óssea. As células-tronco foram recolhidos por sedimentaþÒo e identificados por imunomarcaþÒo com o anticorpo monoclonal anti-CD34 no citómetro de fluxo. A avaliaþÒo da viabilidade miocárdica antes e após a implantaþÒo foi realizada com PET- FDG. Após o término das anastomoses, as células-tronco foram implantadas diretamente por punþÒo em territórios nÒo viáveis. Resultados. Eles sÒo expressos como porcentagens (variáveis categóricas) e média com desvio padrÒo (variáveis contínuas). Para avaliar a importÔncia na mudanþa de fraþÒo de ejeþÒo foi utilizado o teste de Wilcoxon. Considerou-se significante p<0,05. Dos 15 segmentos nÒo viáveis,foram implantados 11 (73%) e quatro (36,36%) foram recuperados. A fraþÒo de ejeþÒo do ventrículo esquerdo avaliada pelo SPECT foi de 30,2±4,9% na fase pré e de 34,8±9,5% no processo de pós, a melhoria foi de 4,6 pontos (p=0,34), 60% dos pacientes melhoraram. Conclus§es. Existe uma relaþÒo entre a concentraþÒo de células CD34+ (baixa: 0,76 %, em média) e a viabilidade do miocárdio. A incidÛncia da viabilidade do miocárdio em 36,36% dos segmentos implantados foi o achado mais importante. O método demonstrou ser seguro, eficaz e reprodutível. O uso de PET-FDG em todos os pacientes para avaliaþÒo de viabilidade, antes e depois da implantaþÒo como método padrÒo-ouro, foi evidÛncia de regeneraþÒo de tecidos.(AU)

Effect of poly(ethylene oxide)-silane graft molecular weight on the colloidal properties of iron oxide nanoparticles for biomedical applications.

The size, charge, and stability of colloidal suspensions of magnetic nanoparticles with narrow size distribution and grafted with poly(ethylene glycol)-silane of different molecular weights were studied in water, biological buffers, and cell culture media. X-ray photoelectron spectroscopy provided information on the chemical nature of the nanoparticle surface, indicating the particle surfaces consisted of a mixture of amine groups and grafted polymer. The results indicate that the exposure of the amine groups on the surface decreased as the molecular weight of the polymer increased. The hydrodynamic diameters correlated with PEG graft molecular weight and were in agreement with a distributed density model for the thickness of a polymer shell end-grafted to a particle core. This indicates that the particles obtained consist of single iron oxide cores coated with a polymer brush. Particle surface charge and hydrodynamic diameter were measured as a function of pH, ionic strength, and in biological buffers and cell culture media. DLVO theory was used to analyze the particle stability considering electrostatic, magnetic, steric, and van der Waals interactions. Experimental results and colloidal stability theory indicated that stability changes from electrostatically mediated for a graft molecular weight of 750 g/mol to sterically mediated at molecular weights of 1000 g/mol and above. These results indicate that a graft molecular weight above 1000 g/mol is needed to produce particles that are stable in a wide range of pH and ionic strength, and in cell culture media.

Toll-like receptor 4 expression on circulating leucocytes in hemolytic uremic syndrome.

Lipopolysaccharide stimulation of toll-like receptor 4 (TLR4) activates signal transduction pathways leading to proinflammatory cytokine secretion. We investigated TLR4 surface receptor expression on peripheral blood neutrophils and monocytes and their ability to modulate inflammatory cytokine release in 15 patients 1, 3, and 10 days after hemolytic uremic syndrome (HUS) onset. Seven patients with Escherichia coli (EHEC)-associated diarrhea and seven healthy controls were also studied. Isolated leucocytes from HUS-onset patients exhibited significantly higher messenger RNA (mRNA) TLR4 expression than controls. Moreover, TLR4 protein expression on neutrophils, determined by flow cytometry, was upregulated, driving dependent proinflammatory cytokine, tumor necrosis factor alpha (TNF-α), and interleukin 8 (IL-8) increase, and decreased anti-inflammatory IL-10 release at HUS onset compared with patients with EHEC diarrhea and controls. TLR4 expression on neutrophils was positively correlated with serum TNF-α levels. Conversely, significant reduction of neutrophil TLR4 receptor expression and lack of cytokine-responsive element activation was shown in patients 3 and 10 days after HUS onset. No differences were demonstrated in TLR4 receptor expression on monocytes among the studied groups. Our results suggest TLR4 expression may be differently regulated on neutrophils and monocytes. They could be dynamically modulated across the early development of HUS on neutrophils, resulting in negative regulation preceded by TLR4 overactivation.

Effect of molecular weight, temperature, and additives on the moisture sorption properties of polyethylene glycol.

Polyethylene glycol (PEG) is a hygroscopic polymer that undergoes the phenomenon of deliquescence once a critical relative humidity (RH(0)) is reached. The purpose of this study was to test the hypothesis that the deliquescence behavior of PEG will be affected by the polymer molecular weight, temperature, and the presence of additives. The deliquescence relative humidity for single component (RH(0)) and binary mixtures (RH(0,mix)) were measured using an automated gravimetric moisture analyzer at 25 and 40 degrees C. Changes in PEG crystallinity after exposure to moisture were qualitatively assessed using powder X-ray diffraction (PXRD). Optical microscopy was used to visually observe the deliquescence phenomenon. For single component systems, decreasing PEG MW and elevating the temperature resulted in a decrease in the observed RH(0). Physical mixtures of acetaminophen and anhydrous citric acid with both PEG 3350 and PEG 100,000 exhibited deliquescence (RH(0,mix)) at a relative humidity below that of either individual component. Qualitative changes in crystallinity were observed from the X-ray diffractograms for each PEG MW grade at high relative humidities, indicating that phase transformation (deliquescence) of the samples had occurred. In conclusion, it was found that the deliquescence behavior of PEG was affected by the polymer MW, temperature, and the presence of additives. This phenomenon may have important implications for the stability of PEG containing formulations.

El envejecimiento de la población extranjera comunitaria en la Comunidad Valenciana y su impacto en el sistema de salud / Ageing of the foreign community in the autonomous community of Valencia and its impact on the health system

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Ordered nanoporous polymers from polystyrene-polylactide block copolymers.

Nanoporous polystyrene monoliths were prepared from polystyrene-polylactide (PS-PLA) block copolymers that form hexagonally packed nanocylinders of PLA in a PS matrix. A morphology diagram was developed to determine the range in composition and molecular weight over which this morphology existed. Macroscopic alignment of these materials gave anisotropic monoliths that were subjected to mild degradation conditions leading to the chemical etching of the PLA. The resulting nanoporous monoliths consisted of a polystyrene matrix containing hexagonally close-packed, oriented, and continuous nanoscopic channels (pore size was tunable through synthesis or blending) lined with chemically accessible hydroxyl functional groups. Both the precursors and the porous materials were analyzed moleculary (size-exclusion chromatography and proton nuclear magnetic resonance spectroscopy) and structurally (small-angle X-ray scattering, scanning electron microscopy, and differential scanning calorimetry). In addition, the surface area and pore size distribution of the nanoporous monoliths were characterized (N2 adsorption measurements). These nanoporous materials have remarkable potential as hosts for nanomaterial synthesis, size-selective catalyst supports, and advanced separations.

Hypofunción esplénica espontánea en lupus eritematoso sistémico y sindrome de Sjögren primario / Spontaneous splenic hypofunction in systemic lupus erythematosus and primary Sjogren syndrome

El objetivo del presente trabajo fue evaluar la existencia de hipoesplenismo funcional en enfermedades autoinmunes. La hipofunción esplénica se determinó por la presencia de cuerpos de Howell-Jolly en eritrocitos de la sangre y posterior centellografía esplénica con radiocoloides marcados con 99Tc, en pacientes en los que se habían descartado otras posibles causas de cuerpo de Howell-Jolly. Se estudiaron extendidos de sangre periférica de 174 pacientes con enfermedades autoinmunes y de 32 otras enfermedades de patogenia inmunológica y 63 indivíduos normales. Se encontró evidencia de hipoesplenia funcional en 4 de 79 pacientes con Lupus Eritematoso Sistémico (LES) y en 2 de 18 casos de Síndrome de Sjorgren Primario (SSP). En uno de los pacientes de LES con hipoesplenia funcional y leve esplenomegalia, se demostró ausencia de cuerpos Howell-Jolly en un estudio realizado 11 meses después de la primera evaluación. En el grupo control, un paciente con leucemia linfática crónica (LLC) y esplenomegalia tenía evidencia de hipoesplenismo. Los resultados obtenidos revelan: 1) Las enfermedades autoinmunes que con mayor frecuencia presentan hipoesplenia funcional son el LES y SSP; 2) La hipoesplenia funcional en enfermedades autoinmunes puede ser transitoria. 3) Esplenomegalia e imagen centelleográfica aumentada del bazo no descartan hipoesplenia

Hypofunción esplénica espontánea en lupus eritematoso sistémico y sindrome de Sj÷gren primario / Spontaneous splenic hypofunction in systemic lupus erythematosus and primary Sjogren syndrome

El objetivo del presente trabajo fue evaluar la existencia de hipoesplenismo funcional en enfermedades autoinmunes. La hipofunción esplénica se determinó por la presencia de cuerpos de Howell-Jolly en eritrocitos de la sangre y posterior centellografía esplénica con radiocoloides marcados con 99Tc, en pacientes en los que se habían descartado otras posibles causas de cuerpo de Howell-Jolly. Se estudiaron extendidos de sangre periférica de 174 pacientes con enfermedades autoinmunes y de 32 otras enfermedades de patogenia inmunológica y 63 indivíduos normales. Se encontró evidencia de hipoesplenia funcional en 4 de 79 pacientes con Lupus Eritematoso Sistémico (LES) y en 2 de 18 casos de Síndrome de Sjorgren Primario (SSP). En uno de los pacientes de LES con hipoesplenia funcional y leve esplenomegalia, se demostró ausencia de cuerpos Howell-Jolly en un estudio realizado 11 meses después de la primera evaluación. En el grupo control, un paciente con leucemia linfática crónica (LLC) y esplenomegalia tenía evidencia de hipoesplenismo. Los resultados obtenidos revelan: 1) Las enfermedades autoinmunes que con mayor frecuencia presentan hipoesplenia funcional son el LES y SSP; 2) La hipoesplenia funcional en enfermedades autoinmunes puede ser transitoria. 3) Esplenomegalia e imagen centelleográfica aumentada del bazo no descartan hipoesplenia (AU)