853 research outputs found

    Critical points in ethylcellulose matrices: Influence of the polymer, drug and filler properties

    Get PDF
    Percolation theory has been applied to study the drug release behaviour in multicomponent inert matrices containing ethylcellulose as a matrix forming polymer. Global influence of major formulation factors such as polymer viscosity, polymer particle size, drug and filler solubility and porosity of the tablets in drug release kinetics has been studied for the first time. Batches containing three viscosity grades of Ethocel™, microcrystalline cellulose (MCC) and lactose as fillers, a lubricant and flow aid mixture and three drugs with different solubility have been manufactured. For some batches, compression pressure was varied in order to obtain matrices with five levels of initial porosity. The behaviour of inert matrices was explained based on the percolation ranges of the main components of the formulation. The effect of the porosity percolation threshold was observed and the existence of a tricoherent drug-polymer-filler system is hypothesized

    3D printed drug delivery systems based on natural products

    Get PDF
    In the last few years, the employment of 3D printing technologies in the manufacture of drug delivery systems has increased, due to the advantages that they offer for personalized medicine. Thus, the possibility of producing sophisticated and tailor-made structures loaded with drugs intended for tissue engineering and optimizing the drug dose is particularly interesting in the case of pediatric and geriatric population. Natural products provide a wide range of advantages for their application as pharmaceutical excipients, as well as in scaffolds purposed for tissue engineering prepared by 3D printing technologies. The ability of biopolymers to form hydrogels is exploited in pressure assisted microsyringe and inkjet techniques, resulting in suitable porous matrices for the printing of living cells, as well as thermolabile drugs. In this review, we analyze the 3D printing technologies employed for the preparation of drug delivery systems based on natural products. Moreover, the 3D printed drug delivery systems containing natural products are described, highlighting the advantages offered by these types of excipients.Ministerio de Ciencia, Innovación y Universidades RTI2018-095041-B-C3

    Collaboration between HPMC and NaCMC in order to Reach the Polymer Critical Point in Theophylline Hydrophilic Matrices

    Get PDF
    Percolation theory has been applied in order to study the existence of critical points as well as the possibility to find a “combined percolation threshold” for ternary hydrophilic matrices prepared with HPMC, NaCMC, and theophylline. For this purpose, different batches of ternary as well as binary hydrophilic matrices have been prepared. Critical points have been found for binary hydrophilic matrices between 21.5 and 31.3% (v/v) of HPMC and between 39 and 54% (v/v) of NaCMC, respectively. In a previous work carried out with the same polymers but a much more soluble drug (KCl), it was demonstrated the existence of a partial collaboration between the polymers in order to establish the gel layer. In this work, it has been observed for the first time the need of a minimum concentration of one of the matrix-forming polymer (between 10 and 20% v/v, approximately) for establishing an effective collaboration

    Comprehensive Analysis of Antioxidant Compounds from Lippia citriodora and Hibiscus sabdari a Green Extracts Attained by Response Surface Methodology

    Get PDF
    Phenolic compounds have shown to have a high bioactive potential against various pathologies, postulating as an interesting alternative to manage some diseases. In this sense, both Lippia citriodora and Hibiscus sabdari a are two botanical sources with a demonstrated high bioactive potential, in which their antioxidant capacity stands out. In this work, the optimization of the extraction conditions for the recovery of phytochemicals from L. citriodora leaves and H. sabdari a calyces has been carried out using Response Surface Methodologies (RSM) considering their total polar compounds measured by HPLC-ESI-TOF/MS and Folin-Ciocalteu assay, and its antioxidant capacity evaluated by Ferric Reducing Antioxidant Power (FRAP) and Trolox Equivalent Antioxidant Capacity (TEAC) assays. The results showed that to maximize the antioxidant capacity in H. sabdari a, a moderate temperature and high ethanol percentage are needed, while a low temperature and a high percentage of ethanol are needed in L. citriodora. In addition, with the results obtained in the multiple response analysis, it is possible to a rm the importance of this type of analysis to develop functional ingredients, taking into account both total content of phenolic compounds and their bioactivity. Furthermore, as confirmed in this study, these analyses can be extrapolated in di erent techniques and in di erent matrices, with phenolic compounds from di erent families being important to develop new high added value products for food, pharmaceutical or cosmetic industries.Ministry of Science, Innovation and Universities RTI2018-096724-B-C22Plan Propio de Investigación of the University of GranadaMinistry of Science, Innovation and UniversitiesUniversity of GranadaAGR274 group 5450Spanish Ministry of Economy and Competitiveness (MINECO) BES-2016-07661

    The use of sociocultural animation techniques at the University improve interpersonal relationships between teachers and students

    Get PDF
    La relación existente entre el profesor y los alumnos puede depender de muchas circunstancias. De entre ellas, este estudio se centra en confirmar que el uso de técnicas de animación sociocultural en el aula hace que se vean mejoradas las relaciones interpersonales entre estos agentes educativos. El procedimiento metodológico seguido se centra en un enfoque interpretativo-descriptivo mediante el uso de unos cuestionarios como técnicas de recogida de datos. Los resultados encontrados confirman nuestra hipótesis inicial y a la vez nos abren las puertas hacia futuras líneas de investigación.Relationships between teachers and students can depend on many circumstances. Specifically, this study focuses on confirming that the use of sociocultural animation techniques in the classroom can improve interpersonal relationships between them. The methodological approach adopted was interpretive-descriptive using questionnaires as a data collection technique. The results confirm our initial hypothesis and also open the doors to future research.Departamento de Psicología Socia

    LC-MS and Spectrophotometric Approaches for Evaluation of Bioactive Compounds from Peru Cocoa By-Products for Commercial Applications

    Get PDF
    Peru is one of the main areas where there are large cocoa crops with special relevance to the economy of this country. In fact, cocoa is a major, economically important, international crop which has been linked to several benefits, such as anti-allergenic, anti-atherogenic, anti-inflammatory, anti-microbial, anti-oxidant, anti-thrombotic, cardioprotective and vasodilatory properties, relating to its bioactive compound content. However, in cocoa industrial processing, several residues or wastes, which are commonly discarded generating a negative impact on the environment, are produced in large amounts. Some of the cocoa by-products, which go underutilized, could be a good source of bioactive compounds with high utility for the development of innovative products in nutraceutical, medical or pharmaceutical industries. For this reason, the aim of this study is to qualitatively determine the phytochemical composition of husk and bean extracts from different cocoa-growing areas and processes from Peru by high performance liquid chromatography coupled to mass spectrometry. Furthermore, we aim to evaluate their phenolic and flavan-3-ol contents and antioxidant capacities for the purpose of highlighting the potential of cocoa by-products from these cultivars as functional ingredients. In total, 49 chemical compounds were detected in the analyzed extracts. Comparing both husks and beans, bean extracts were characterized by high content in flavonoids whereas husk extracts had a higher content of phenolic acids. The presence of these compounds together with the bioactivity results suggest that these matrices may be further studied for their revaluation in the development of high added-value products in nutraceutical, medical, and pharmaceutical industries.Ministry of Science, Innovation and Universities RTI2018-096724-B-C22Spanish Ministry of Economy and Competitiveness (MINECO) BES-2016-076618Ministry of Science, Innovation and UniversitiesAGR274 group 5450University of Granad

    Pleasure, Health and Sociability. Food Fact and Food Choice through Iberian Ham

    Get PDF
    A medida que avanzan los estudios sobre el polisémico ámbito de la alimentación humana, resulta más necesario considerar mayor número de variables para analizar con solvencia el hecho alimentario. Más allá de los estudios sobre las fases de producción y distribución, nuestra propuesta se centra en la fase del consumo y trata de identificar los elementos que explican por qué las sociedades seleccionan y prefieren unos alimentos en detrimento de otros. Actualmente, la selección alimentaria está intrínsecamente presente en el hecho alimentario de las sociedades modernas, relegando a un segundo plano los factores biológicos y fisiológicos, en relación a parámetros dominantes comparados con el placer, la salud y la sociabilidad. Mediante una combinación de técnicas cuantitativas y cualitativas, este estudio propone la relevancia de dimensiones como el placer y la salud como elementos que guían a los consumidores para elegir un determinado producto gourmet, como es el caso del jamón ibérico en España.Esta investigación es el resultado del proyecto I+D (CSO2013-42468-P) del Ministerio de Economía y Competitividad Las marcas de calidad en el mundo rural: nuevos retos para productores y consumidores

    The impact of glucocorticoids and anti-cd20 therapy on cervical human papillomavirus infection risk in women with systemic lupus erythematosus

    Get PDF
    OBJECTIVE: To identify the prevalence and factors associated with cervical human papillomavirus infection in women with systemic lupus erythematosus METHODS: This cross-sectional study collected traditional and systemic lupus erythematosus-related disease risk factors, including conventional and biologic therapies. A gynecological evaluation and cervical cytology screen were performed. Human papillomavirus detection and genotyping were undertaken by PCR and linear array assay. RESULTS: A total of 148 patients were included, with a mean age and disease duration of 42.5±11.8 years and 9.7±5.3 years, respectively. The prevalence of squamous intraepithelial lesions was 6.8%. The prevalence of human papillomavirus infection was 29%, with human papillomavirus subtype 59 being the most frequent. Patients with human papillomavirus were younger than those without the infection (38.2±11.2 vs. 44.2±11.5 years, respectively; p = 0.05), and patients with the virus had higher daily prednisone doses (12.8±6.8 vs. 9.7±6.7 mg, respectively; p = 0.01) and cumulative glucocorticoid doses (14.2±9.8 vs. 9.7±7.3 g, respectively; p = 0.005) compared with patients without. Patients with human papillomavirus infection more frequently received rituximab than those without (20.9% vs. 8.5%, respectively; p = 0.03). In the multivariate analysis, only the cumulative glucocorticoid dose was associated with human papillomavirus infection. CONCLUSIONS: The cumulative glucocorticoid dose may increase the risk of human papillomavirus infection. Although rituximab administration was more frequent in patients with human papillomavirus infection, no association was found. Screening for human papillomavirus infection is recommended in women with systemic lupus erythematosus

    Safety and immediate humoral response of COVID-19 vaccines in chronic kidney disease patients:the SENCOVAC study

    Get PDF
    BACKGROUND: Chronic kidney disease (CKD) patients are at high-risk for severe Covid-19. The multicentric, observational and prospective SENCOVAC study aims to describe the humoral response and safety of SARS-CoV-2 vaccines in CKD patients. Safety and immediate humoral response results are reported here. METHODS: Four cohorts of patients were included: kidney transplant (KT) recipients, haemodialysis (HD), peritoneal dialysis (PD) and non-dialysis CKD patients from 50 Spanish centres. Adverse events after vaccine doses were recorded. At baseline and on day 28 after the last vaccine dose, anti-Spike antibodies were measured and compared between cohorts. Factors associated with development of anti-Spike antibodies were analyzed. RESULTS: 1746 participants were recruited: 1116 HD, 171 PD, 176 non-dialysis CKD patients and 283 KT recipients. Most patients (98%) received mRNA vaccines. At least one vaccine reaction developed after the first dose in 763 (53.5%) and after the second dose in 741 (54.5%) of patients. Anti-Spike antibodies were measured in the first 301 patients. At 28 days, 95% of patients had developed antibodies: 79% of KT, 98% of HD, 99% of PD and 100% of non-dialysis CKD patients (p<0.001). In a multivariate adjusted analysis, absence of an antibody response was independently associated to KT (OR 20.56, p = 0.001) and to BNT162b2 vaccine (OR 6.03, p = 0.023). CONCLUSION: The rate of anti-Spike antibody development after vaccination in KT patients was low but in other CKD patients it approached 100%; suggesting that KT patients require persistent isolation measures and booster doses of a Covid-19 vaccine. Potential differences between Covid-19 vaccines should be explored in prospective controlled studies

    Autoantibody screening in Guillain-Barré syndrome

    Get PDF
    Background: Guillain?Barré syndrome (GBS) is an acute inflammatory neuropathy with a heterogeneous presentation. Although some evidences support the role of autoantibodies in its pathogenesis, the target antigens remain unknown in a substantial proportion of GBS patients. The objective of this study is to screen for autoantibodies targeting peripheral nerve components in Guillain-Barré syndrome. Methods: Autoantibody screening was performed in serum samples from all GBS patients included in the International GBS Outcome study by 11 different Spanish centres. The screening included testing for anti-ganglioside antibodies, anti-nodo/paranodal antibodies, immunocytochemistry on neuroblastoma-derived human motor neurons and murine dorsal root ganglia (DRG) neurons, and immunohistochemistry on monkey peripheral nerve sections. We analysed the staining patterns of patients and controls. The prognostic value of anti-ganglioside antibodies was also analysed. Results: None of the GBS patients (n = 100) reacted against the nodo/paranodal proteins tested, and 61 (61%) were positive for, at least, one anti-ganglioside antibody. GBS sera reacted strongly against DRG neurons more frequently than controls both with IgG (6% vs 0%; p = 0.03) and IgM (11% vs 2.2%; p = 0.02) immunodetection. No differences were observed in the proportion of patients reacting against neuroblastoma-derived human motor neurons. Reactivity against monkey nerve tissue was frequently detected both in patients and controls, but specific patterns were only detected in GBS patients: IgG from 13 (13%) patients reacted strongly against Schwann cells. Finally, we confirmed that IgG anti-GM1 antibodies are associated with poorer outcomes independently of other known prognostic factor
    corecore