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1.
Ecotoxicol Environ Saf ; 191: 110222, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31982683

RESUMEN

Cylindrospermopsin (CYN) is a cyanotoxicant which occurrence is increasing due to climate change. Cylindrospermopsin is able to exert damage in the organism at several levels, among them, in the nervous system. Moreover, it is important to take into account that it is not usually present isolated in nature, but in combination with some other pollutants, being the case of the pesticide chlorpyrifos (CPF). Thus, the aim of the present work was to assess the effects of the interaction of CYN in combination with CPF in the human neuroblastoma cell line SH-SY5Y by evaluating cytotoxicity and mechanistic endpoints. The mixtures 0.25 + 21, 0.5 + 42, 1 + 84 µg/mL of CYN + CPF based on cytotoxicity results, were evaluated, and the isobologram method detected an antagonistic effect after 24 and 48 h of exposure. Moreover, although no alterations of reactive oxygen species were detected, a significant decrease of glutathione levels was observed after exposure to both, CPF alone and the combination, at all the concentrations and times of exposure assayed. In addition, CYN + CPF caused a marked decrease in the acetylcholinesterase activity, providing similar values to CPF alone. However, these effects were less severe than expected. All these findings, together with the morphological study results, point out that it is important to take into account the interaction of CYN with other pollutants. Further research is required to contribute to the risk assessment of CYN and other contaminants considering more realistic exposure scenarios.


Asunto(s)
Toxinas Bacterianas/toxicidad , Cloropirifos/toxicidad , Inhibidores de la Colinesterasa/toxicidad , Contaminantes Ambientales/toxicidad , Insecticidas/toxicidad , Uracilo/análogos & derivados , Alcaloides , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Toxinas de Cianobacterias , Glutatión/metabolismo , Humanos , Uracilo/toxicidad
2.
Sci Total Environ ; 668: 547-565, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-30856566

RESUMEN

Microcystins (MCs) and cylindrospermopsin (CYN) are among the most frequent toxins produced by cyanobacteria. These toxic secondary metabolites are classified as hepatotoxins and cytotoxin, respectively. Furthermore, both may present the ability to induce damage to the nervous system. In this sense, there are many studies manifesting the potential of MCs to cause neurotoxicity both in vitro and in vivo, due to their probable capacity to cross the blood-brain-barrier through organic anion transporting polypeptides. Moreover, the presence of MCs has been detected in brain of several experimental models. Among the neurological effects, histopathological brain changes, deregulation of biochemical parameters in brain (production of oxidative stress and inhibition of protein phosphatases) and behavioral alterations have been described. It is noteworthy that minority variants such as MC-LF and -LW have demonstrated to exert higher neurotoxic effects compared to the most studied congener, MC-LR. By contrast, the available studies concerning CYN-neurotoxic effects are very scarce, mostly showing inflammation and apoptosis in neural murine cell lines, oxidative stress, and alteration of the acetylcholinesterase activity in vivo. However, more studies are required in order to clarify the neurotoxic potential of both toxins, as well as their possible contribution to neurodegenerative diseases.


Asunto(s)
Toxinas Bacterianas/toxicidad , Microcistinas/toxicidad , Sistema Nervioso/efectos de los fármacos , Uracilo/análogos & derivados , Alcaloides , Apoptosis , Encéfalo , Cianobacterias , Toxinas de Cianobacterias , Estrés Oxidativo , Uracilo/toxicidad
3.
Chemosphere ; 224: 751-764, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30851527

RESUMEN

Microcystin-LR (MC-LR) and Cylindrospermopsin (CYN) are produced by cyanobacteria. Although being considered as a hepatotoxin and a cytotoxin, respectively, different studies have revealed neurotoxic properties for both of them. The aim of the present work was to study their cytotoxic effects, alone and in combination, in the SH-SY5Y cell line. In addition, toxicity mechanisms such as oxidative stress and acetylcholinesterase (AChE) activity, and morphological studies were carried out. Results showed a cytotoxic response of the cells after their exposure to 0-100 µg/mL of MC-LR or 0-10 µg/mL CYN in both differentiated and undifferentiated cells. Thus, CYN resulted to be more toxic than MC-LR. Respect to their combination, a higher cytotoxic effect than the toxins alone in the case of undifferentiated cells, and almost a similar response to the presented by MC-LR in differentiated cells were observed. However, after analyzing this data with the isobolograms method, an antagonistic effect was mainly obtained. The oxidative stress study only showed an affectation of glutathione levels at the highest concentrations assayed of MC-LR and the combination in the undifferentiated cells. A significant increase in the AChE activity was observed after exposure to MC-LR in undifferentiated cells, and after exposure to the combination of both cyanotoxins on differentiated cells. However, CYN decreased the AChE activity only on differentiated cultures. Finally, the morphological study revealed different signs of cellular affectation, with apoptotic processes at all the concentrations assayed. Therefore, both cyanotoxins isolated and in combination, have demonstrated to cause neurotoxic effects in the SH-SY5Y cell line.


Asunto(s)
Toxinas Bacterianas/toxicidad , Microcistinas/toxicidad , Neurotoxinas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Uracilo/análogos & derivados , Acetilcolinesterasa/metabolismo , Alcaloides , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Toxinas de Cianobacterias , Antagonismo de Drogas , Combinación de Medicamentos , Humanos , Toxinas Marinas , Neuroblastoma/tratamiento farmacológico , Uracilo/toxicidad
4.
Artículo en Inglés | MEDLINE | ID: mdl-24328862

RESUMEN

Two organo-modified clays for food contact applications were developed to produce hydrophobically modified montmorillonite and hence to obtain better compatibility between the biopolymer and the filler (nanoclay). These nanofillers were characterised by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction and thermogravimetric analysis (TGA) in order to study their composition, structure and thermal stability. The fillers were used to reinforce polylactic acid (PLA) bottles, which were characterised using different techniques such as mechanical and barrier properties, morphology and thermal stability. The results were compared with conventional PLA bottles. The use of the modified clay in PLA bottles was found to lead to an improvement in mechanical and barrier properties. Finally, cytotoxicity tests were carried out with the organo-modified clays using Caco-2 and HepG2 cell lines, with uptake of neutral red as a basal cytotoxicity biomarker.


Asunto(s)
Silicatos de Aluminio/química , Silicatos de Aluminio/toxicidad , Embalaje de Alimentos/métodos , Nanocompuestos/química , Nanocompuestos/toxicidad , Bentonita/química , Bentonita/toxicidad , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Arcilla , Células Hep G2 , Calor , Humanos , Ácido Láctico/química , Ácido Láctico/toxicidad , Ensayo de Materiales , Microscopía Electrónica de Transmisión , Nanocompuestos/ultraestructura , Permeabilidad , Poliésteres , Polímeros/química , Polímeros/toxicidad , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
5.
Toxicon ; 78: 18-34, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24291634

RESUMEN

Cylindrospermopsin (CYN) is a cytotoxic cyanotoxin produced by several cyanobacteria species. It has been demonstrated that CYN is a potent protein and glutathione synthesis inhibitor, and induces genotoxicity and oxidative stress. The present study investigated the protective role of two different doses of N-Acetylcysteine (NAC) (22 and 45 mg/fish/day) against the pathological changes induced in tilapia (Oreochromis niloticus) orally exposed to a single dose of pure CYN or CYN from an Aphanizomenon ovalisporum CYN-producer strain (200 µg/kg of CYN in both cases). Moreover, an immunohistochemical (IHC) analysis was carried out in order to elucidate the CYN distribution in exposed fish. The histological findings were more pronounced when fish were intoxicated with CYN from the cyanobacterial strain, being liver and kidney the main targets for CYN toxicity. NAC pre-treatment was effective reducing the damage induced by CYN, especially at the highest dose employed (45 mg/fish/day), with a total prevention in all organs. The IHC analysis showed that CYN-antigen appeared mainly in the liver and gastrointestinal tract, although it was also present in kidney and gills. In this case, the immunopositive results were more abundant in those fish exposed to pure CYN. NAC reduced the number of immunopositive cases in a dose-dependent way. Therefore, NAC can be considered a useful chemoprotectant in the prophylaxis and treatment of CYN-related intoxications in fish.


Asunto(s)
Acetilcisteína/farmacología , Aphanizomenon/química , Cíclidos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Uracilo/análogos & derivados , Alcaloides , Animales , Toxinas Bacterianas , Toxinas de Cianobacterias , Relación Dosis-Respuesta a Droga , Tracto Gastrointestinal/efectos de los fármacos , Inmunohistoquímica/veterinaria , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Uracilo/toxicidad
6.
Rev. toxicol ; 30(2): 144-148, jul.-dic. 2013. ilus
Artículo en Español | IBECS (España) | ID: ibc-126293

RESUMEN

El aceite esencial de los componentes del género Allium, principalmente ajo y cebolla, presenta propiedades antioxidantes y antibacterianas debidas a la presencia de compuestos azufrados en su composición. La industria alimentaria ha comenzado a desarrollar nuevos sistemas de envasado activo a partir de polímeros seleccionados, a los que se incorporan aceites esenciales que, por sus propiedades, contribuyen a aumentar la vida útil de los alimentos perecederos. En este sentido, se hace necesario evaluar la seguridad asociada al uso de estas sustancias en envases alimentarios que van a estar en contacto con el consumidor a través del alimento. El objetivo del presente estudio fue determinar la citotoxicidad producida por dipropil sulfuro y dipropil disulfuro, dos de los componentes del aceite esencial de ajo y cebolla, en la línea celular Caco-2, células humanas procedentes de carcinoma de colon. Los biomarcadores ensayados fueron el contenido total de proteínas, la captación de rojo neutro y la reducción de la sal de tetrazolio (3-(4,5-dimetiltiazol-2- il)-5-(3-carboximetoxifenil)-2-(4sulfofenil)-2H-tetrazolio). Las células fueron expuestas durante 2, 4 y 8 h a concentraciones comprendidas entre 0 y 200 μM. Los resultados no mostraron diferencias significativas frente al control para ninguno de los tres marcadores, lo que demuestra que bajo las condiciones de los ensayos ambos compuestos azufrados no son citotóxicos para esta línea celular gastrointestinal y podrían ser útiles en la industria alimentaria para desarrollar envases activos (AU)


Allium spp. essential oil, mainly from garlic and onion, possesses different beneficial properties, for example antioxidant and antimicrobial effects, due to the presence of sulfur compounds. Food industry is developing new active packaging systems that include the essential oil of garlic in their structure, in order to improve the shelf-life of perishable products. Therefore it is necessary to evaluate the safety associated with the use of these substances in food packaging that will be in contact with the consumer through food. The aim of our study was to evaluate in vitro the cytotoxicity of dipropyl sulfide and dipropyl disulfide. For this purpose, we used the human Caco-2 cell line, from human small intestinal mucosa carcinoma. The assayed cytotoxicity biomarkers were the total protein content, neutral red uptake and reduction of the 3-(4,5-dimethylthiazol-2-yl)-5-(3- carboximethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium salt. Cells were exposed to dipropyl sulfide and dipropyl disulfide in concentrations between 0-200 μM for 2, 4 and 8 h. After periods of exposure, no alterations were observed in any of the biomarkers assayed. These results suggest that both organosulfur compounds are safety options for food industry and could be a choice in the development of active packaging. (AU)


Asunto(s)
Células CACO-2/citología , Células CACO-2/metabolismo , Células CACO-2/efectos de la radiación , Aceites Volátiles/toxicidad , Análisis de los Alimentos/métodos , Estudios de Factibilidad , Células CACO-2/clasificación , Pruebas Inmunológicas de Citotoxicidad/métodos , Pruebas Inmunológicas de Citotoxicidad , Aceites Volátiles/efectos adversos , Aceites Volátiles/química , Aceites Volátiles/envenenamiento , Alimentos/toxicidad
7.
Ars pharm ; 51(supl.2): 464-470, mayo 2010. tab
Artículo en Español | IBECS (España) | ID: ibc-88669

RESUMEN

ininterrumpidamente desde 2006/07 hasta la actualidad. Propósito: tutela de alumnos de nuevo ingreso por parte de alumnos de cursos superiores (AATT) bajo la supervisión de Profesores Tutores. Pretende generar una actitud responsable en los AATT y favorecerles el desarrollo de habilidades sociales. El objetivo de este trabajo es recoger las opiniones de los AATT (algunos comenzaron en ediciones anteriores y continúan desinteresadamente). Se aborda mediante un análisis DAFO. Conclusión: se han detectado factores estratégicos críticos, para una vez identificados, usarlos y apoyar en ellos la marcha del “Programa de Alumnos Tutores”, consolidando las fortalezas, minimizando las debilidades, aprovechando las ventajas de las oportunidades, y eliminando o reduciendo las amenazas(AU)


The "Student Mentor Program" (Faculty of Pharmacy, US) has been running since 2006/07 – to present. Purpose: to mentor new students by senior students (Mentor Students) under the supervision of mentor professors. It aims to generate a responsible attitude in students and tutors to encourage the development of social skills. Objective: To collect the views of mentor students (some started in previous years and continue to selflessly), through a SWOT analysis. Conclusion: it has been found critical strategic factors. It intends to use these factors for strengthening the "Student Mentor Program"(AU)


Asunto(s)
Humanos , Masculino , Femenino , Tutoría/métodos , Tutoría/tendencias , Facultades de Farmacia/normas , Facultades de Farmacia/tendencias , Aptitud , Tutoría/organización & administración , Indicadores Sociales , 35174
8.
Ars pharm ; 51(supl.2): 487-493, mayo 2010. graf, ilus
Artículo en Español | IBECS (España) | ID: ibc-88672

RESUMEN

La Facultad de Farmacia de la Universidad de Sevilla (US) tiene en marcha un Programa de Alumnos Tutores desde 2006/07 con el objetivo de que alumnos de cursos superiores (AATT) tutelen a alumnos de nuevo ingreso (1x3). Pretende generar una actitud responsable en los AATT y favorecerles el desarrollo de habilidades sociales, objetivos cualitativos dentro de la educación universitaria que sirven como preparación previa a su inserción en el mundo laboral. La actividad es supervisada por Profesores Tutores (1x3) que analizan la evolución de ambos grupos de alumnos. Es una supervisión activa a través de distintas vías de acción para ayudar a la consecución de objetivos, tales como entrevistas periódicas, revisión de informes, acciones de apoyo como charlas sobre técnicas de estudio, coloquios sobre salidas laborales, exposiciones de las experiencias personales de algunos alumnos recientemente egresados, gestión estratégica de búsqueda de empleo, elaboración de portafolios,…Con respecto a la evolución del programa, el número de profesores ha crecido moderadamente llegando a una situación estable, mientras que el número de alumnos, tanto tutores como tutelados, ha crecido en un ritmo constante acorde a las restricciones indicadas. Los resultados son muy positivos, entendiéndose que el proyecto se enmarca en un contexto más cualitativo que cuantitativo y que el principal objetivo es el robustecimiento de la experiencia y asentar una dinámica de apoyo hacia los alumnos de nuevo ingreso y de planificación de tareas, tutela y responsabilidad en general de los alumnos tutores(AU)


The Faculty of Pharmacy of the University of Seville (US) has developed a Student Mentoring Program (from 2006/07 - present). The main objective of this project is that senior students act as Mentor Students for students at their first year in the University (1x3). It aims to generate a responsible attitude in mentor students and to promote the development of social skills, qualitative goals within higher education that serve as preparation prior to their integration into the world of work.This activity is supervised by Mentor Professors (1x3) that analyze the evolution of both groups of students. It is an active monitoring through various actions such as regular interviews, review of reports, support operations such as lectures on study skills, seminars on job opportunities, statements of personal experiences of some recently graduated students, strategic management job search, portfolio development...With regard to the development of the program, the number of Mentor Professors has grown moderately, reaching a stable condition, while the number of students, both tutor and supervised, has grown steadily in line with the restrictions indicated. The results are very positive, considering the more qualitative than quantitative character of the project and that the main objectives are the strengthening of the experience and the establishment of a dynamic support to the new students and scheduling and general responsibility for mentor students(AU)


Asunto(s)
Humanos , Masculino , Femenino , Facultades de Farmacia/organización & administración , Facultades de Farmacia/tendencias , Tutoría/métodos , Entrevista Psicológica/métodos , Medios Audiovisuales/normas , Medios Audiovisuales , Materiales de Enseñanza/normas , Facultades de Farmacia/normas , Tutoría/organización & administración , Tutoría/normas , Tutoría/tendencias , Comisión sobre Actividades Profesionales y Hospitalarias/normas
9.
Rev. toxicol ; 26(2/3): 87-92, 2009. tab
Artículo en Español | IBECS (España) | ID: ibc-79370

RESUMEN

La nanotecnología es una ciencia multidisciplinar que está teniendoun gran auge en la actualidad, ya que proporciona productos(nanopartículas) con nuevas propiedades fisicoquímicas, que son lasque hacen que tengan una gran cantidad de aplicaciones. Laexposición humana a estas nanopartículas se puede producirprincipalmente por las vías respiratoria (nanopartículas suspendidasen el aire), dérmica (nanopartículas ambientales, cosméticos) y oral(alimentos, agua). Por vía pulmonar las nanopartículas activan losmecanismos de defensa o son internalizadas en los intersticios. Porvía dérmica se pueden acumular en el estrato córneo o en los folículospilosos, o bien atravesarlo y acumularse en la dermis. Por vía oralpueden ser absorbidas por las células epiteliales del intestino. Laexposición también se puede producir a través de la instrumentaciónmédica o prácticas clínicas, ya que se usan, por ejemplo, en eltratamiento y diagnóstico del cáncer de mama y en el control deinfecciones en cirugía. Una vez las nanopartículas han sidoabsorbidas, se distribuyen por vía sanguínea y linfática, alcanzandodiferentes órganos, tales como huesos, riñones, páncreas, bazo,hígado y corazón, en los que quedan retenidas y ejercen sus efectostóxicos, aunque esto también se utiliza como una forma devectorización de fármacos. La toxicidad de estas nanopartículasdepende, entre otros factores, de su persistencia en los órganos y de siel hospedador puede provocar una respuesta biológica paraeliminarlas. Los mecanismos de toxicidad no se conocen conexactitud, aunque parece ser que se incluyen daño en membranascelulares, disrupción del potencial de membrana, oxidación deproteínas, genotoxicidad, formación de especies reactivas de oxígenoe inflamación. Estudios sobre las vías respiratorias han mostradodisminución de la viabilidad celular in vitro, producción de estrésoxidativo e inflamación...(AU)


Nanotechnology is a multi-disciplinary science which is having a great growth at present, as it provides products (nanoparticles) withnew physico-chemical properties that can have many applications.Human exposure to these nanoparticles can be produced byrespiratory (airborne nanoparticles), dermal (atmosphericnanoparticles, cosmetics) and oral routes (food, water). Byrespiratory route, nanoparticles can stimulate the defensemechanisms or can penetrate into gaps. By dermal route, they can beaccumulated in the stratum corneum or in the hair follicles, or gothrough it and be accumulated in the dermis. By gastrointestinal routethey can be absorbed by the epithelial cells of the intestine. Humancan also be exposed by medical instrumentation or clinic practices, asnanoparticles are used, for example, for treatment and diagnostic ofbreast cancer and to control surgery infections. Once nanoparticleshave been absorbed they are distributed by blood and lymphaticstream, reaching different organs, such as bones, kidneys, pancreas,spleen, liver and heart, where they are retained and can produce theirtoxic effects, although this ability is also used for drugs delivery. Thetoxicity of these nanoparticles depends, among other factors, on theirpermanence in organs and if the host can produce a biologicalresponse to eliminate them. The toxicity mechanisms have not beencompletely elucidated, although they are known to produce cellmembrane damages, membrane potential disruption, proteinsoxidation, genotoxicity, production of reactive oxygen species, andinflammation. Studies on the respiratory exposure have demonstrateda diminution of the cellular viability in vitro, oxidative stressproduction, and inflammation. On skin have been demonstratedtoxicity and oxidative stress, although other authors have shown theabsence of irritation and allergic reactions...(AU)


Asunto(s)
Humanos , Masculino , Femenino , Nanopartículas/toxicidad , Nanopartículas/uso terapéutico , Factores de Riesgo , Técnicas Biosensibles , Sustancias Peligrosas/toxicidad , Residuos Tóxicos/políticas , Sustancias Tóxicas , 35509 , Nanopartículas/efectos adversos , Nanotecnología/normas , Microquímica/normas , Farmacocinética , Pruebas de Carcinogenicidad/tendencias
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