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1.
Rev. cuba. invest. bioméd ; 40(supl.1): e1176, 2021. tab, graf
Article in English | LILACS, CUMED | ID: biblio-1289469

ABSTRACT

Nowadays, there is a growing interest in biodegradable polymers-based materials due to their diverse application in the biomedical field. Most studied systems involve biocompatible micro and nanodevices, such as liposomes, dendrimer, micelles or polymeric nanogels. The use of Radiation Technology, specifically gamma radiation, to produce micro and nanogels raises the possibility to obtain higher purity products, an important feature for biomedical and pharmaceutical applications. The radio-induced synthesis, characterization, cytotoxicity evaluation, and immunological response of nanogels are described in this study. Nanogel synthesis was performed in the absence of oxygen using aqueous polyvinylpyrrolidone solutions. Crosslinking reactions were carried out at 25 °C in a gamma irradiation chamber with a 60Co source. Nanogels properties were analysed by Scanning Electron Microscopy, Attenuated Total Reflection-Fourier Transform Spectroscopy, Dynamic Light Scattering, and Viscosimetry. The cytotoxicity and immunological response were evaluated by MTT test and analysis of the neutrophil respiratory burst. The results showed that nanogels formation strongly depends on the total absorbed dose. The nanogels have an elliptical shape and their chemical structure is similar to the initial polymer. The nanogels are biocompatible and promote a low-intensity neutrophil activation, similar to the well-characterized biomaterial TiO2, suggesting their potential biomedical uses(AU)


En la actualidad existe un interés creciente en los materiales biodegradables basados en polímeros, debido a sus diversas aplicaciones en la esfera de la biomedicina. En la mayoría de los sistemas estudiados participan micro- y nanodispositivos biocompatibles, tales como liposomas, dendrímeros, micelas o nanogeles poliméricos. El uso de la tecnología de radiaciones, en particular de radiaciones gamma, para producir micro- y nanogeles, eleva la posibilidad de obtener productos de mayor pureza, un rasgo importante con vistas a su aplicación biomédica y farmacéutica. El estudio describe la síntesis radioinducida, caracterización, evaluación de la citotoxicidad y respuesta inmunológica de los nanogeles. La síntesis de los nanogeles se realizó en ausencia de oxígeno, usando soluciones acuosas de polivinilpirrolidona. Las reacciones de entrecruzamiento se realizaron a 25 ºC en cámara de irradiación gamma con una fuente de 60Co. Las propiedades de los nanogeles se analizaron mediante microscopía electrónica de barrido, espectroscopia por transformada de Fourier total atenuada, dispersión dinámica de luz y viscosimetría. La citotoxicidad y la respuesta inmunológica se evaluaron mediante prueba MTT y análisis del estallido respiratorio de neutrófilos. Los resultados muestran que la formación de nanogeles depende en gran medida de la dosis total absorbida. Los nanogeles tienen forma elíptica y su estructura química es similar a la del polímero inicial. Los nanogeles son biocompatibles y promueven una activación de neutrófilos de baja intensidad similar al bien caracterizado material TiO2, lo que sugiere usos biomédicos potenciales(AU)


Subject(s)
Humans , Male , Female , Gamma Rays/therapeutic use , Nanogels/standards , Cytotoxicity Tests, Immunologic
2.
Acta sci., Biol. sci ; 39(2): 195-200, abr.- jun. 2017. tab
Article in English | LILACS | ID: biblio-846930

ABSTRACT

The present study evaluated the acute toxicity at the cellular level of processed juice ready for consumption Orange and Grape flavors, produced by five companies with significant influence on the food market of South American countries, especially in Brazil. This evaluation was performed in root meristem cells of Allium cepa L., at the exposure times of 24 and 48 hours, directly with marketed liquid preparations. Based on the results, it was found that fruit juices, of all companies considered, promoted significant antiproliferative effect to root meristems at the exposure time of 24 hours and resulted in at both exposure times, statistically significant number of mitotic spindle changes and chromosomal breaks. Therefore, under the study conditions, all juice samples analyzed were cytotoxic, genotoxic and mutagenic to root meristem cells. These results indicate that such beverages have relevant potential to cause cellular disorders and, thus, need to be evaluated more fully in more complex test systems, as those in rodents, and then establish specific toxicity at the cellular level of these juices and ensure the well-being of those who consume them.


Objetivou-se neste trabalho avaliar a toxicidade aguda em nível celular de sucos industrializados prontos para beber, sabor laranja e uva, de cinco empresas alimentícias de reconhecida reputação no mercado de alimentos em países da América do Sul, especialmente o Brasil. Esta avaliação se deu por meio das células meristemáticas de raízes de Allium cepa L., nos tempos de exposição 24 e 48h, diretamente nos preparados líquidos comercializados. Com base nos resultados obtidos verificou-se que os sucos de frutas, de todas as empresas consideradas, promoveram expressivo efeito antiproliferativo aos meristemas de raízes já no tempo de exposição 24h, e ocasionaram número estatisticamente significativo de alterações de fuso mitótico e quebras cromossômicas nas células do tecido analisado em todo o tempo de análise. Portanto, nas condições de estudo estabelecidas, os sucos das empresas avaliadas foram citotóxicos, genotóxicos e mutagênicos. Estes resultados são importantes em razão de indicarem que tais alimentos têm relevante potencial em causar distúrbios celulares e, portanto, devem ser avaliados em sistemas com testes mais complexo, como os em roedores, para, dessa forma, estabelecer com propriedade a toxicidade em nível celular desses alimentos e assegurar o bem-estar daqueles que os consomem.


Subject(s)
Cytotoxicity Tests, Immunologic , Genotoxicity , Industry , Juices , Mutagenicity Tests
3.
Braz. J. Pharm. Sci. (Online) ; 53(1): e15235, 2017. tab, graf
Article in English | LILACS | ID: biblio-839451

ABSTRACT

Abstract A novel series of platinum (II) complexes was synthesized and the complexes were evaluated for their in vitro cytotoxicity against four human cancer cells lines. Five platinum complexes showed activity against at least one tumor cell line. Complexes 3 and 6 were promising, being active, at micromolar concentrations, against all the assayed tumor cell lines. Compound 3 was selected for further studies in mice with Ehrlich solid tumors and it was able to reduce the rate of tumor growth significantly during the first seven days. However, at the end of the experiments, there was no significant difference between the group of animals treated with 3 and the control group. The low solubility of the compound in the assay conditions can explain, at least in part, these results.


Subject(s)
Animals , Male , Female , Rats , Platinum/analysis , Drug Screening Assays, Antitumor/instrumentation , Cytotoxicity Tests, Immunologic/classification , Carcinoma, Ehrlich Tumor/classification , Cytotoxins/adverse effects
4.
Biosci. j. (Online) ; 32(2): 566-573, mar./abr. 2016. tab, graf
Article in English | LILACS | ID: biblio-965388

ABSTRACT

This study aimed to evaluate the cytotoxicity of intracanal medications on L929 fibroblast cells at different periods of observation. The following experimental groups were studied: calcium hydroxide with camphorated paramonochlorophenol and glycerin (CPG); iodoform with glycerin (IG); calcium hydroxide with iodoform and distilled water (CIW); iodoform with distilled water (IW); calcium hydroxide with distilled water (CW); Otosporin ® (OT); and a control group composed of cells and culture medium. Eluates were prepared from each group and placed in contact with 1 x 105 cells/well for periods of 30 minutes, 12, 24, 48 and 72 hours, 5 and 7 days. After each experimental period, a cytotoxicity test was performed using methyltetrazolium (MTT) and a spectrophotometer at an optical density of 570 nm to analyze cell viability. The ANOVA and Tukey test with a significance level of 5% was used to analyze the data. At 30 minutes and at 12 hours, all groups were equal to the control group. At 24 hours, there was greater cytotoxicity in the IG group than in the control group (P<0.001). At 48 hours, only the OT group was cytotoxic (P <0.001). At 72 hours and at 5 days, the most cytotoxic groups were CW and OT. At 7 days, the IW and CPG groups were the least cytotoxic (P <0.001). With respect to experimental time, significant differences between 24 hours and 7 days were observed in all groups. Otosporin® was the most cytotoxic medication, followed by calcium hydroxide with distilled water.


Este estudo teve como objetivo avaliar a citotoxicidade de medicações intracanais em células L929 de fibroblastos em diferentes períodos de observação. Os seguintes grupos experimentais foram estudados: hidróxido de cálcio com paramonoclorofenol canforado e glicerina (CPG); iodofórmio com glicerina (IG); hidróxido de cálcio com iodofórmio e água destilada (CIW); iodofórmio com água destilada (IW); hidróxido de cálcio com água destilada (CW); Otosporin® (OT); e um grupo controle composto por células e meio de cultura. Os eluatos foram preparados a partir de cada grupo e colocados em contato com 1 x 105 células/poço, por períodos de 30 minutos, 12, 24, 48 e 72 horas, 5 e 7 dias. Depois de cada período experimental, um teste de citotoxicidade foi realizado utilizando metiltetrazólio (MTT) e um espectrofotômetro a uma densidade óptica de 570 nm para analisar a viabilidade celular. A análise de variância e o teste de Tukey com nível de significância de 5% foi utilizado para analisar os dados. Em 30 minutos e em 12 horas, todos os grupos foram iguais ao grupo controle. Em 24 horas, houve uma maior citotoxicidade no grupo IG do que no grupo controle (P<0,001). Em 48 horas, apenas o grupo OT foi citotóxico (P<0,001). Em 72 horas e em 5 dias, os grupos mais citotóxicos foram CW e OT. Aos 7 dias, os grupos IW e CPG foram os menos citotóxicos (P<0,001). Com relação ao tempo experimental, foram observadas diferenças significativas entre 24 horas e 7 dias em todos os grupos. Conclusão: Otosporin® foi o medicamento mais citotóxico, seguido de hidróxido de cálcio com água destilada.


Subject(s)
Calcium Hydroxide , Cytotoxicity Tests, Immunologic , Iodoformium , Endodontics , Fibroblasts
5.
Rev. cuba. hematol. inmunol. hemoter ; 32(1): 30-42, ene.-mar. 2016.
Article in Spanish | LILACS | ID: lil-794144

ABSTRACT

La búsqueda e identificación de nuevos compuestos activos para la terapéutica del cáncer se ha centrado esencialmente en la investigación de productos naturales y de sus análogos sintéticos. El presente trabajo pretende sistematizar los conocimientos sobre las bases moleculares de la actividad citotóxica de los compuestos quinoides y su uso como agente antitumoral. Se realizó una revisión de artículos originales, de corte experimental, publicados en la década 2004-2014 en algunas bases de datos de la Biblioteca Virtual de Salud (BVS). Se constató que numerosos estudios han avalado la capacidad de los productos quinoides de inhibir el crecimiento celular, sustentado en sus posibilidades de dañar al ADN por estrés oxidativo y de interactuar de modo biorreductivo con otras biomoléculas. Además, que la potencia de la citotoxicidad de los compuestos quinoides se incrementa ante cadenas laterales alquiladas y anillos aromatizados unidos al motivo quinona. Las evidencias experimentales sugieren un promisorio futuro de estas moléculas como agentes antitumorales, en base a su citotoxicidad y elevada selectividad ante líneas celulares neoplásicas(AU)


The search and identification of new active compounds for cancer therapy has focused mainly on research of natural products and their synthetic analogs. This paper aims to systematize the knowledge of the molecular basis of the cytotoxic activity of the quinoid compounds and their use as an antitumor agent. A review was performed on original articles, experimental section, published in the 2004-2014 decade in some databases of the Virtual Health Library (VHL). Numerous studies have supported the ability of quinoid products inhibiting cell growth, based on their ability to damage DNA by oxidative stress and thus have a biorreductive interaction with other biomolecules. Furthermore, the power of cytotoxicity increases quinoid compounds alkylated with side chains attached to rings and quinone flavored motif. Experimental evidence suggests a promising future of these molecules as antitumor agents, based on their high selectivity and cytotoxicity against neoplastic cell lines(AU)


Subject(s)
Humans , Anticarcinogenic Agents/therapeutic use , Chenopodium quinoa/toxicity , Cytotoxicity Tests, Immunologic/methods , In Vitro Techniques/methods
6.
IJPR-Iranian Journal of Pharmaceutical Research. 2016; 15 (1): 311-322
in English | IMEMR | ID: emr-177562

ABSTRACT

Primula auriculata [Tootia] is one of the most important local medicinal plants in Hamedan district, Iran. To investigate cytotoxicity and apoptosis induction of crude methanolic extract and different fraction of it we compared several methods on HT-29 human colon Adenocarcinoma cells. Cancer cell proliferation was measured by 3-[4, 5-dimethylthiazolyl]-2, 5-diphenyl-tetrazolium bromide [MTT] assay and apoptosis induction was analyzed by fluorescence microscopy [acridin orange/ethidium bromide, annexin V/propidium iodide staining, TUNEL assay and Caspase-3 activity assay]. Crude methanolic extract [CM] inhibited the growth of malignant cells in a dose-dependent manner. Among solvent fractions, the dichloromethane fraction [CF] was found to be the most toxic compared to other fractions. With double staining methods, high percentage of 40 microg/mL of [CM] and [CF] treated cells exhibited typical characteristics of apoptotic cells. Apoptosis induction was also revealed by Apoptotic fragmentation of nuclear DNA and activation of caspas-3 in treated cells. These findings indicate that crude methanolic extract and dichloromethan fraction of P.auriculata induced apoptosis and inhibited proliferation in colon cancer cells and could be used as a source for new lead structures in drug design to combat colon cancer


Subject(s)
Adenocarcinoma , Colon , Apoptosis , Cell Line , Plants, Medicinal , Phytotherapy , Plant Extracts , Cytotoxicity Tests, Immunologic
7.
Saude e pesqui. (Impr.) ; 8(3): 509-516, set-dez 2015. tab
Article in Portuguese | LILACS | ID: biblio-831978

ABSTRACT

O reino vegetal oferece maior variedade de substâncias potencialmente úteis nas enfermidades humanas, especialmente aquelas causadas por micro-organismos. Um dos maiores problemas de Saúde Pública enfrentado nos últimos anos é o agravamento da resistência bacteriana e isto se tornou mais grave com a dificuldade para a descoberta de novos antibióticos. O objetivo deste estudo foi avaliar o perfil fitoquímico, analisando a atividade antimicrobiana e citotóxica dos extratos das plantas Schinus terebinthifolia, Maytenus ilicifolia Reissek, Tabebuia avellanedae, Anadenanthera colubrina (Vell.) Brenan. Os extratos das plantas estudadas apresentaram taninos e alcalóides em sua composição fitoquímica. T. avellanedae não teve atividade inibitória frente aos micro-organismos testados, enquanto que os outros extratos testados apresentaram atividade inibitória em diferentes concentrações. No teste de citotoxicidade pode-se observar que T. avellanedae apresentou alta toxicidade. A atividade antimicrobiana desejada pode ser encontrada em espécies de plantas medicinais, para isso deve-se verificar cientificamente o uso popular de plantas medicinais, caracterizando seus princípios ativos e o mecanismo de ação destes.


The vegetal kingdom provides a great variety of compounds which are highly useful in human illnesses, especially those caused by microorganisms. One of the most relevant issues during the last decades is bacterial resistance, which is extremely serious due to difficulties in discovering new antibiotic agents. Current study evaluates the phytochemical profile by analyzing the antimicrobial and cytotoxic activity of the extracts of the plants Schinusterebinthifolia, Maytenusilicifolia Reissek, Tabebuia avellanedae, Anadenanthera colubrina (Vell.) Brenan. Plants´ extracts included tannins and alkaloids in their phytochemical compositions. T. avellanedae did not have any inhibitory activity to the microorganisms tested, whereas the other extracts tested presented inhibitory activity at different concentrations. The cytotoxicity test showed that T. avellanedae had high toxicity. The required antimicrobial activity may be found in several species of medicinal plants. However, the use of folk medicine plants should be scientifically assessed so that their main active agents and mechanisms may be characterized.


Subject(s)
Cytotoxicity Tests, Immunologic , Microbial Sensitivity Tests , Phytochemicals , Anti-Infective Agents
8.
Acta sci., Health sci ; 37(2): 175-179, jul.-dez. 2015. tab
Article in English | LILACS | ID: biblio-832091

ABSTRACT

While a 42-year-old male patient was being prepared for deceased-donor renal transplantation, anti-HLA-A2 antibodies were detected in the serum by enzyme-linked immunosorbent assay (ELISA) method. The patient denied any transfusion history and previous transplant. Crossmatch by complement dependent cytotoxicity (CDC) and CDC with anti -human globulin (CDC-AHG) proved negative with a four-cell panel with positive typing for HLA-A2. Adsorption of antibodies with platelets and analysis of eluate were suggested to elucidate discrepancies in results by ELISA and by CDC-AHG. ELISA showed that adsorbed serum with platelets did not reveal antibodies for HLA-A2 specificity and suggested that they were removed by their specific binding with HLA-A2 antigens on the platelet surface. Eluate analysis by ELISA showed antibodies for HLA-A2 specificity. No antibodies for HLA-A2 specificity in the non-adsorbed serum were detected by CDC-AHG method. Revision of patient's data showed that a previous transfusion had occurred, which may have been the source of HLA sensitization. The suggested method may be a contribution towards the evaluation of sensitivity between CDC-AHG and ELISA methods for characterizing antibodies in the patient's serum.


Enquanto um paciente do sexo masculino de 42 anos de idade estava sendo preparado para o transplante renal de doador falecido, anticorpos anti-HLA-A2 foram detectados no soro pelo método de ensaio imunoenzimático (ELISA). O paciente negava história de transfusão e transplante anterior. Prova-cruzada por citotoxicidade dependente de complemento (CDC) e CDC com antiglobulina humana (CDC-AGH) foram negativos com um painel de quatro células com tipagem positiva para HLA-A2. O método de adsorção de anticorpos com plaquetas e análise do eluato foi sugerido para explicar as discrepâncias dos resultados de ELISA e CDC-AGH. O método de ELISA mostrou que o soro adsorvido com plaquetas não revelou anticorpos para especificidade HLA-A2, sugerindo que eles foram removidos por meio de sua ligação específica com os antígenos HLA-A2 na superfície das plaquetas. A análise do eluato por ELISA mostrou anticorpos para especificidade HLA-A2. Nenhum anticorpo para especificidade HLA-A2 foi detectada no soro não adsorvido pelo método de CDC-AGH. Revisão dos dados do paciente mostrou que houve transfusão anterior, podendo ter sido a fonte de sensibilização HLA. O método sugerido é uma contribuição para avaliação da sensibilidade entre os métodos de CDC-AGH e ELISA em caracterizar anticorpos no soro do paciente.


Subject(s)
Humans , Male , Adult , Antibodies , Cytotoxicity Tests, Immunologic , Enzyme-Linked Immunosorbent Assay , HLA Antigens , Kidney Transplantation
9.
Rev. estomat. salud ; 22(2): 7-12, 20140000.
Article in Spanish | LILACS, COLNAL | ID: biblio-877915

ABSTRACT

Introducción: Los materiales de uso odon - tológico son sometidos a diferentes pruebas para determinar su compatibilidad, bioac - tividad, y demostrar que son aptos para permanecer en el medio oral sin producir una respuesta adversa. Con tal propósito ac - tualmente en el mundo se emplean distintas técnicas como los cultivos celulares, técni - cas de biología molecular hasta el empleo de larvas de camarón (brineshrimplarvae) mejor conocidas como Artemia salina. Objetivo: Caracterizar cinco materiales odontológicos, utilizando la prueba de citotoxicidad con larvas de camarón Ar - temia salina. Materiales y métodos: Se realizó prueba de citotoxicidad de unas muestras de Titanio IV, Silicona Pesada, Acrílico de Auto-cu- rado, Resina de foto-curado y Eugenolato, utilizando el método de Artemia salina. Resultados: El ensayo de citotoxicidad con Artemia salinamostróque para la viabilidad de las larvas el eugenolato es 100 % toxico - ya que eliminó todas las larvas, y los otros productos mostraron biocompatibilidad en los siguientes porcentajes: titanio tipo IV 100%, silicona 46%, acrílico 62% y resina 72%. Conclusión: El método de la Artemia salina es sencillo y económico para realizar estu- dios de citotoxicidad, no requiere mayor tecnología en infraestructura, y combinado con otras técnicas de biología celular puede convertirse en un método tan específico como se desee. El titanio tipo IV mostró 0% y el eugenolato 100%de citotoxicidad para viabilidad de las larvas de Artemia Salin


Background: The dental materials are subjected to various tests for consistency, bioactivity, and demonstrate that they can remain in the oral environment without producing an adverse response. Currently for this purpose worldwide are employed different techniques such as cell culture, techniques of molecular biology and the use of shrimp larvae (brineshrimplarvae) better known as Artemia salina. Objective: Characterize five dental mate - rials using a cytotoxicity test with larval shrimp Artemia salina. Materials and methods: A cytotoxicity study was performed on samples of Tita - nium Type IV, Silicone Heavy, Auto-cured acrylic resin and photo-curing and Euge- nolatousing the method of Artemia salina. Results: The cytotoxicity assay for Artemia Salina showed no viability foreugenolato because all the larvaes were eliminated, and other products showed biocompatibility in the following percentages. Titanium type IV 100%, the silicone 46%, acrylic 62% and resin 72%. Conclusions: The method of brine shrimp is a simple and economical method for studies of cytotoxicity, requires greater infrastructure technology, and combined with other techniques of cell biology can become as specific method as desired. The - re is viability for the artemiasalina larvae with type IV titanium of 100% and with eugenolato of 0%


Subject(s)
Cytotoxicity Tests, Immunologic , Dental Materials , Dentistry , Materials Testing , Oral Medicine , Bone and Bones , Materials Testing , Methods , Periodontics , Periodontium
10.
Egyptian Journal of Hospital Medicine [The]. 2014; 57 (October): 554-564
in English | IMEMR | ID: emr-160253

ABSTRACT

Nanoparticles of silver have many important applications and are among the most commonly used nanomaterials. They are increasingly used in a variety of both medical and consumer products which includes: spectrally selective coating for solar energy absorption and intercalation material for electrical batteries, as optical receptors, polarizing filters, catalysts in chemical reaction and bio-labeling. Nanosilver [Ag-NP] has both antibacterial and antiviral activity. Yet, the knowledge about the systemic toxicity of nanosilver is relatively limited. The aim of work: To evaluate the potential toxicity of small size 10nm silver nanoparticles using two different doses [0.1 ml and 0.4 ml] focusing on the ultrastructural changes occurring in mice hepatocytes. This study was performed using three groups of mice. The animals of the first group were given a daily intravenous injection of 0.1 ml of silver nanoparticles for 28 consecutive days. The second group was treated with 0.4 ml of silver nanoparticles for 28 consecutive days. The third group served as a control group in which the animals did not receive any vehicle. The study was focused on the ultrastructure of the liver. Ultrastructure observations of liver cells of mice Treated with any of the two doses [0.1 and 0.4 ml] of 10 nm Ag-NP indicated severe accumulation of dark deposits of Ag-NP in the cytoplasm and the cell organelles. Our study revealed that nanosilver used in doses of 0.1 and 0.4 ml led to deposits in the cells and induced damage of cell components especially the nucleus, mitochondria and chromatin


Subject(s)
Male , Animals, Laboratory , Metal Nanoparticles/toxicity , Cytotoxicity Tests, Immunologic/methods , Liver/cytology , Liver/ultrastructure , Mice
11.
Acta sci., Biol. sci ; 35(4): 557-562, out.-dez. 2013. tab
Article in English | LILACS | ID: biblio-849321

ABSTRACT

The objective of this work was to evaluate the cytotoxic effect of the food dyes erythrosine, brilliant blue and red 40 on the cell cycle of Allium cepa L. Each dye was evaluated at doses of 0.4 and 4.0 ml, at exposure times of 24 and 48 hours, in onion root tip cells. Cells and the presence of chromosomal aberrations were analyzed throughout the whole cell cycle, totaling 5,000 cells for each group of bulbs. The mitotic index was calculated and the statistical analysis was conducted through the Chi-square test (p < 0.05). From the obtained results, it was verified that the food additives erythrosine and brilliant blue were not cytotoxic to the cells of the test system. However, the red 40 dye, at the two evaluated doses and the two exposure times used in this bioassay have promoted a significant reduction in cell division and induced the emergence of anaphasic and telophasic bridge aberrations and micronucleated cells. Additional cytotoxicity studies should be conducted to add information to these and other previously obtained results in order to evaluate, with property, the action of these three dyes on a cellular level.


Este trabalho teve por objetivo avaliar o efeito citotóxico dos corantes alimentares eritrosina, azul brilhante e vermelho 40 sobre o ciclo celular de Allium cepa L. Cada corante foi avaliado nas doses de 0,4 e 4,0mL, nos tempos de exposição de 24 e 48h, em células meristemáticas de raízes de cebolas. Foram analisadas células em todo o ciclo celular e a presença de aberrações cromossômicas, totalizando 5.000 células para cada grupo de bulbos. Calculou-se o índice mitótico e a análise estatística foi feita por meio do teste Qui-quadrado (p < 0,05). A partir dos resultados obtidos, verificou-se que os aditivos alimentares eritrosina e azul brilhante não foram citotóxicos às células do sistema-teste em questão. Já o corante vermelho 40, nas duas doses avaliadas e nos dois tempos de exposição estipulados para este bioensaio, promoveu redução significativa da divisão celular e induziu o aparecimento de aberrações dos tipos ponte anafásica, ponte telofásica e célula micronucleada. Estudos adicionais de citotoxicidade devem ser conduzidos para se somar a estes para assim avaliar, com propriedade, a ação destes três corantes em nível celular.


Subject(s)
Cytotoxicity Tests, Immunologic , Food Coloring Agents , Onions
12.
Rio de Janeiro; s.n; 2013. 79 f p.
Thesis in Portuguese | LILACS | ID: lil-756638

ABSTRACT

P. aeruginosa é um importante agente de infecções relacionadas à assistência em saúde. Habitualmente, o estabelecimento de infecções agudas é precedido pela colonização das mucosas dos pacientes. Não se sabe, porém, se os processos infecciosos são causados pelas próprias cepas bacterianas colonizadoras ou por outras com que os pacientes entrem em contato, dotadas ou não de maior potencial de virulência ou de resistência a antimicrobianos que as tornem mais eficientes como agentes infecciosos. Assim, este estudo teve como objetivos i) investigar a existência de potenciais diferenças entre amostras de P. aeruginosa que causaram apenas colonização e aquelas responsáveis por infecção, isoladas de um mesmo paciente, quanto a seus fenótipos de virulência e de não susceptibilidade a antimicrobiamos; ii) pesquisar a existência de associação entre características dos paciente, incluindo o tipo de evolução clínica, com as demais variáveis estudadas. No estudo foram incluídos 21 pacientes que desenvolveram infecção por P. aeruginosa durante sua internação no Centro de Terapia Intensiva do Hospital Universitário Clementino Fraga Filho, entre abril de 2007 e abril de 2008. De cada paciente foram selecionadas duas amostras bacterianas: a primeira isolada durante o episódio de infecção e a amostra colonizadora obtida imediatamente antes da ocorrência da infecção. As amostras selecionadas foram estudadas quanto a i) expressão de três mecanismos de virulência (citotoxicidade, aderência a células epiteliais respiratórias humanas e capacidade de formação de biofilme); ii) presença de genes codificadores das proteínas efetoras do sistema de secreção do tipo 3 (SST3 - exoS, exoT, exoU e exoY); iii) perfil de susceptibilidade a antimicrobianos, iv) perfil de fragmentação do DNA cromossômico por eletroforese em gel de campo pulsado (PFGE). As amostras bacterianas obtidas de infecções agudas foram significativamente mais citotóxicas que aquelas obtidas de colonização...


P. aeruginosa is an important agent of healthcare-associated infections. The establishment of acute infectious episodes is usually preceded by colonization of patient mucosa. However, it remains unknown whether the infectious processes are caused by bacterial strains previously colonizing the patient or by additional strains the patient may come into contact. These new isolates may carry greater virulence potential or antibiotic resistance that makes them more efficient as an infecting agent. Thus, the objetives of the present study were i) to investigate the existence of potential differences between P. aeruginosa isolates obtained from a colonized mucosa and isolates accounting for infectious processes, recovered from the same patient, with respect to virulence phenotypes and non-susceptibility to antimicrobial agents; ii) to investigate the existence of association between patient features, including the type of clinical outcome, with bacterial characteristics. The study included 21 patients who developed P. aeruginosa infection during their stay in the Intensive Care Unit of the University Hospital Clementino Fraga Filho, from April 2007 to April 2008. Two P. aeruginosa isolates were selected from each patient: the first isolate recovered from the infectious episode and the colonizing isolate obtained immediately before the onset of the infection. Features from the isolates investigated included: i) expression of three virulence mechanisms (cytotoxicity, adherence to human respiratory epithelial cells and biofilm formation); ii) presence of the genes encoding type III secretion system effector proteins (TTSS, exoS , exoT , exoU and exoY); iii) antimicrobial susceptibility profile; iv) profile of the bacterial chromossomic DNA fragmentation following analysis by pulsed-field gel electrophoresis (PFGE). The bacterial isolates obtained from acute infections were significantly more cytotoxic than colonizing strains...


Subject(s)
Humans , Cross Infection/epidemiology , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa , Bacterial Adhesion , Biofilms , Cytotoxicity Tests, Immunologic , Intensive Care Units , Cross Infection/microbiology , Patients , Virulence/physiology
13.
Article in Chinese | WPRIM | ID: wpr-264232

ABSTRACT

The cytotoxicity of medical ultrasonic couplant was tested by MTT assay and agar overlay test. By MTT assay, when the inoculum density was high, the cytotoxicity level was low, or vice versa. The cytotoxicity grade tested by agar overlay was not accord to MTT assay's too. MTT assay is suitable to test the cytotoxicity of medical ultrasonic couplant because it is quantitative and more sensitive, however, the experimental condition and the preparative method of extraction should be determined.


Subject(s)
Animals , Cell Line , Colorimetry , Cytotoxicity Tests, Immunologic , Methods , Mice , Ultrasonics
14.
Indian J Biochem Biophys ; 2012 Dec; 49(6): 451-457
Article in English | IMSEAR | ID: sea-144086

ABSTRACT

Six different extracts from Eucalyptus citriodora leaves were investigated for their anticancer effect. Extracts were prepared using a range of polar and non-polar solvents to leach out maximum active components. Phytochemical analysis of the extracts revealed the presence of anthraquinones, cardiac glycosides, flavonoids, saponins and tannins. Cytotoxic activity of different extracts was tested in vitro against seven human cancer cell lines from seven different tissues, such as SW-620 (colon), HOP-62 (lung), PC-3 (prostate), OVCAR-5 (ovary), HeLa (cervix), IMR-32 (neuroblastoma) and HEP-2 (liver). The ethyl acetate, chloroform and 50% methanolic extract displayed highest anti-proliferative effect in a dose-dependent manner. In vivo anti-tumor activity was evaluated against murine tumor (solid) model of Ehrlich ascites carcinoma and Sarcoma 180. The results showed that ethyl acetate and aqueous extracts suppressed the growth of Ehrlich ascites carcinoma (29.79% and 18.48%, respectively), but showed little growth inhibition in case of Sarcoma 180 (13. 86% and 8.57%, respectively). The activity might be due to the flavonoids, tannins and saponins that are present in all the extracts of the plant. Further investigation is required for the isolation of active principle(s) from the ethyl acetate extract, which has shown significant in vitro and in vivo anticancer potential.


Subject(s)
Cell Proliferation/drug effects , Cytotoxicity Tests, Immunologic , Cytotoxicity Tests, Immunologic/methods , Disease Models, Animal , Eucalyptus/therapeutic use , Mice , Neoplastic Stem Cells , Plant Extracts/therapeutic use , Saponins/therapeutic use , Flavonoids/therapeutic use , Tannins/therapeutic use
15.
Pesqui. vet. bras ; 32(9): 931-935, set. 2012. tab
Article in English | LILACS | ID: lil-654376

ABSTRACT

The aim of this study was to research the occurrence of Salmonella spp. and Escherichia coli in feces samples of sparrows, as well as to identify the pathogenicity, cytotoxicity and sensitivity profile of the isolates to antimicrobial use. Two hundred and twenty eight sparrows were captured in eight farms. The in vitro pathogenicity test was performed by the isolates culture on congo red-magnesium oxalate Agar, whilst the in vivo pathogenicity test was performed in one day-old chicks. In order to study the cytotoxic effects of indicators, samples were inoculated into Vero cells. The results obtained for Escherichia coli isolation confirmed the presence of this microorganism in 30 (13.2%) of the evaluated samples. Out of those isolates, 10 (33.3%) presented the capacity of absorbing ongo red. As for in vivo pathogenicity a 68.0% of mortality rate of the evaluated samples was observed. Out of 20 isolates tested for cytotoxin production, none of them presented cytotoxic effect in the Vero cells. The Salmonella spp was isolated only in one sample (0.04%), and it was identified as Salmonella enterica subspecies houtenae. Results obtained through this research indicate the need for new studies to identify other virulence factors of E. coli samples and to delineate the phylogenetic profile of the isolates in order to establish a relation with colibacillosis outbreaks in chickens and broilers in the studied region, as well as to analyze the critical points in the aviculture productive chain to identify the source of Salmonella enterica subspecies houtenae.


Objetivou-se com este estudo pesquisar a ocorrência de Salmonella spp. e Escherichia coli em amostras de fezes de pardais, além de avaliar a patogenicidade, citotoxicidade e perfil de sensibilidade dos isolados frente a antimicrobianos. Foram capturados 228 pardais em oito granjas. O teste de patogenicidade in vitro foi realizado por meio do cultivo dos isolados em ágar oxalato de magnésio acrescido de vermelho de congo, enquanto o teste de patogenicidade in vivo foi realizado em pintos de um dia. Para o estudo dos indicadores dos efeitos citotóxicos, as amostras foram inoculadas em células Vero. Os resultados obtidos quanto ao isolamento de Escherichia coli confirmaram a presença deste microorganismo em 30 (13,2%) amostras analisadas. Destes isolados, dez (33,3%) apresentaram capacidade de absorção do vermelho congo. Quanto à patogenicidade in vivo observou-se uma taxa de mortalidade de 68,0% das amostras analisadas. Dos 20 isolados testados quanto à produção de citotoxina, nenhum apresentou efeito citotóxico nas células Vero. Obteve-se o isolamento de Salmonella spp. em apenas uma amostra (0,04%), sendo tipificada em Salmonella enterica subespécie houtenae. Os resultados obtidos nesta pesquisa indicam a necessidade da realização de novos estudos para identificar outros fatores de virulência das amostras de E. coli e traçar o perfil filogenético dos isolados para estabelecer uma relação com surtos de colibacilose em galinhas e frango de corte na região estudada, além de analisar os pontos críticos na cadeia produtiva da avicultura para identificar a origem da Salmonella enterica subespécie houtenae.


Subject(s)
Escherichia coli/isolation & purification , Escherichia coli/pathogenicity , Sparrows/parasitology , Salmonella/isolation & purification , Salmonella/pathogenicity , Feces/parasitology , Cytotoxicity Tests, Immunologic/veterinary , Parasitic Sensitivity Tests/veterinary
16.
Arq. bras. med. vet. zootec ; 64(4): 881-886, Aug. 2012. ilus, tab
Article in Portuguese | LILACS | ID: lil-647688

ABSTRACT

Foram coletados 100 suabes retais e 100 suabes de carcaças bovinas em matadouros do estado de São Paulo, e um total de 326 estirpes de E. coli foram identificadas, sendo 163 de amostras retais e 163 de amostras de carcaça. Todos os isolados submetidos à PCR para detecção dos genes das toxinas Stx1 e Stx2 foram identificados como não-O157 e fenotipados pelo teste da citotoxicidade em células Vero. Das 26 estirpes que apresentaram apenas o gene stx1, das 56 que apresentaram apenas o gene stx2 e das 30 estirpes que apresentaram ambos os genes, 17 (65,4%), 42 (75%) e 22 (73,3%), respectivamente, foram positivas ao teste de citotoxicidade. Não houve diferença estatística entre os três perfis genéticos e na positividade ao teste de citotoxicidade. Os resultados mostram a alta frequência de expressão dos fatores de virulência das STEC de bovinos.


In the present study 100 rectal and 100 carcass swabs were collected from bovines at slaughterhouses in São Paulo state, and the total of 326 E. coli strains were identified (163 from rectal samples and 163 from carcass samples). All the isolates were submitted to PCR for Stx1 and Stx2 toxin gene detection and all strains were identified as non-O157 and phenotyped by the citotoxicity test in Vero cells. Out of 26 strains that presented only the stx1 gene, 56 that presented only the stx2 gene and 30 that presented both genes, 17 (65.4%), 42 (75%) and 22 (73.3%), respectively, were positive for the citotoxicity test. There was no statistically significant difference among these three toxinotyping profiles and positivity in the citotoxicity test, but the results show high frequency of virulence factor expression of bovine.


Subject(s)
Animals , Shiga Toxin , Shiga-Toxigenic Escherichia coli , Abattoirs , Cytotoxicity Tests, Immunologic/veterinary , Virulence
17.
Article in Chinese | WPRIM | ID: wpr-326267

ABSTRACT

<p><b>OBJECTIVE</b>To assess the immunotoxicologic effects of genetically modified drought resistant wheat T349 with GmDREB1 gene.</p><p><b>METHODS</b>A total of 250 female BALB/c mice (6-8 week-old, weight 18-22 g) were divided into five large groups (50 mice for each large group) by body weight randomly. In each large group, the mice were divided into five groups (10 mice for each group) by body weight randomly, which were set as negative control group, common wheat group, parental wheat group, genetically modified wheat group and cyclophosphamide positive control group, respectively. Mice in negative control and positive control group were fed with feedstuff AIN-93G, mice in common wheat group, non-genetically modified parental wheat group and genetically modified wheat group were fed with feedstuffs added corresponding wheat (proportion up to 76%) for 30 days, then body weight, organ coefficient of spleen and thymus, peripheral blood lymphocytes phenotyping, serum cytokine, serum immunoglobulin, antibody plaque-forming cell (PFC), serum 50% hemolytic value (HC50), mitogen-induced splenocyte proliferation, delayed-type hypersensitivity (DTH) reaction and phagocytic activities of phagocytes were detected respectively.</p><p><b>RESULTS</b>After 30 days raise, among negative control group, common wheat group, non-genetically modified parental wheat group, genetically modified wheat group and cyclophosphamide positive control group, mice body weight were (21.0±0.3), (20.4±0.7), (21.1±1.0), (21.1±1.0), (19.4±1.0) g, respectively (F=7.47, P<0.01); organ coefficient of spleen were (0.407±0.047)%, (0.390±0.028)%, (0.402±0.042)%, (0.421±0.041)%, (0.304±0.048)%, respectively (F=12.41, P<0.01); organ coefficient of thymus were (0.234±0.032)%, (0.246±0.028)%, (0.249±0.040)%, (0.234±0.034)%, (0.185±0.039)%, respectively (F=5.58, P<0.01); the percentage of T cell in peripheral blood were (70.43±4.44)%, (68.33±5.37)%, (73.04±2.68)%, (74.42±2.86)%, (90.42±1.66)%, respectively (F=57.51, P<0.01); the percentage of B cell were (13.89±3.19)%, (15.34±4.84)%, (13.06±4.22)%, (12.93±2.36)%, (3.01±0.96)%, respectively (F=12.79, P<0.01); the percentage of Th cell were (55.87±3.80)%, (55.24±4.60)%, (57.92±3.70)%, (59.57±2.54)%, (77.37±2.31)%, respectively (F=68.58, P<0.01);the Th/Ts ratio were 4.16±0.29, 4.73±0.96, 4.19±0.78, 4.52±0.40, 6.34±0.73, respectively (F=17.57, P<0.01);the serum IgG were (1046.38±210.67), (1065.49±297.22), (1517.73±299.52), (1576.67±241.92), (1155.88±167.05) µg/ml, respectively (F=10.53, P<0.01); the serum IgM were (333.83±18.97), (327.73±27.72), (367.47±27.18), (363.42±46.14), (278.71±24.42) µg/ml, respectively (F=12.11, P<0.01); the serum IgA were (51.69±10.10), (42.40 ± 8.35), (32.11±4.22), (37.12±4.90), (41.45±8.89) µg/ml, respectively (F=8.25, P<0.01); the PFC were (29.2±14.6), (28.0±20.0), (34.8±30.9), (33.2±25.1), (4.8±5.3) per 10(6) splenocyte, respectively (F=3.33, P<0.05); the HC50 were 82.3±6.5, 79.7±4.6, 75.8±4.1, 74.9±3.6, 70.8±2.1, respectively (F=9.99, P<0.01);the LPS-induced splenocyte proliferation were 0.21±0.10, 0.21±0.14, 0.26±0.12, 0.25±0.14, 0.07±0.06, respectively (F=4.18, P<0.05).</p><p><b>CONCLUSION</b>The genetically modified drought-resistant wheat T349 was substantially equivalent to parental wheat in the effects on immune organs and immunologic functions of mice, and it didn't show immunotoxicity.</p>


Subject(s)
Animals , Cytotoxicity Tests, Immunologic , Cytotoxicity, Immunologic , Droughts , Female , Mice , Mice, Inbred BALB C , Plants, Genetically Modified , Allergy and Immunology , Toxicity , Triticum , Genetics , Allergy and Immunology , Toxicity
18.
Indian J Med Microbiol ; 2011 Oct-Dec; 29(4): 414-417
Article in English | IMSEAR | ID: sea-143867

ABSTRACT

Complement-dependent lymphocytotoxicity crossmatches (n=217) between 47 deceased donors and 150 potential renal recipients were retrospectively studied. A negative cross match was reported in 48 (22.1%), doubtful positive in 126 (58.1%), weakly positive in 32 (14.7%) and positive in 11 (5.1%). No autoantibodies were detected. Renal transplantation was performed in 35.5% of the potential recipients. There was no incidence of hyperacute rejection. The graft survival rate was 88% at 15 months of follow up. The study concludes that a negative pretransplant lympocytotoxicity crossmatch using the basic National Institute of Health technique eliminates hyperacute rejection, but carries drawbacks, which require modification and supplementation with more sensitive and specific assays.


Subject(s)
Adolescent , Adult , Aged , Child , Child, Preschool , Complement System Proteins/immunology , Cytotoxicity Tests, Immunologic/methods , Female , Graft Rejection/immunology , Graft Survival/immunology , Histocompatibility Testing/methods , Humans , Kidney Transplantation/immunology , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Young Adult
19.
Rev. cuba. farm ; 45(1): 101-108, ene.-mar. 2011.
Article in Spanish | LILACS | ID: lil-584574

ABSTRACT

Es objetivo del trabajo evaluar el efecto de 10 extractos de plantas medicinales sobre el crecimiento de la línea celular humana de carcinoma de pulmón A549. El efecto de los extractos sobre la células tumorales se midió a través de un ensayo colorimétrico mediante el empleo del bromuro de 3-(4,5-dimetil-tiazol-2-yl)-2,5-difenil tetrazolio a concentraciones entre 3,9-250 µg/mL durante 72 h y se calculó la concentración citotóxica media para cada uno. Del total de los extractos evaluados solo cuatro (Parthenium hysterophorus, Bixa orellana, Momordica charantia y Cucurbita maxima) evidenciaron concentraciones citotóxicas medias inferiores a 100 µg/mL. Excepto Parthenium hysterophorus, las restantes se emplean en la medicina tradicional para el tratamiento del cáncer. Los extractos de Cecropia peltata, Melia azedarach, Annona glabra, Artemisia absintium, Lepidium virginicum y Bidens pilosa no mostraron efectos citotóxicos significativos. Los extractos de plantas que se emplean en la medicina tradicional para el tratamiento del cáncer, mostraron citotoxicidad sobre las células tumorales. El conocimiento etnobotánico representa una herramienta importante en la selección de plantas medicinales, en la búsqueda de nuevos compuestos para el tratamiento del cáncer


To evaluate the effect of 10 Cuban medicinal plant extracts on the human lung tumor cell line A549. The effect of the plant extracts on tumor cells was determined by a colorimetric assay using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) at concentrations ranging from 3,9-250 µg/mL for 72 hours and the mean cytotoxic concentration was calculated for each of them. The ethanolic extracts of Parthenium hysterophorus, Bixa orellana, Momordica charantia and Cucurbita maxima showed mean cytotoxic concentrations under 100 µg/mL. Except for P hysterophorus, the others are used in traditional medicine to fight cancer. The remaining extracts from Cecropia peltata, Melia azedarach, Annona glabra, Artemisia absintium, Lepidium virginicum and Bidens pilosa did not show significant cytotoxic effects. the plant extracts for cancer treatment in traditional medicine showed cytotoxic effect on the tumor cell lines. Ethnobotanical data represent an important tool for medicinal plants screening in the quest for new compounds to treat cancer


Subject(s)
Humans , Cytotoxicity Tests, Immunologic , Plant Extracts , Tumor Cells, Cultured
20.
Article in English | WPRIM | ID: wpr-819537

ABSTRACT

OBJECTIVE@#To elucidates the immunoprophylactic potential of glutathion-s-transferase (GST) from cattle filarial parasite Setaria digitata (S. digitata) against lymphatic filariasis.@*METHODS@#GST was purified through affinity chromatography (SdGST) and chacterized by SDS-PAGE and Nano-LC MS/MS analysis. Antibody isotypes to SdGST were measured by ELISA. Antibody dependant cellular cytotoxicity (ADCC) was performed in vitro using sera from immunized animals and immune individuals. T-cell proliferation and cytokine response to SdGST in different groups of filariasis were measured. Immunoprophylactic potential of SdGST was evaluate in animal model.@*RESULTS@#SdGST exhibited 30-fold enhancement of enzyme activity over crude parasitic extract. It was found to be 26 kDa by SDS-PAGE. Nano LC-MS/MS analysis followed by blast search showed 100% homology with Dirofilaria immitis (D. immitis) and only 43% with Homo sapiens (H. sapiens). Immunoblotting analysis showed putatively immune individuals carry significant level of antibodies to SdGST as compared with microfilaraemics. Immunized sera and sera endemic normal could neutralize the enzymatic activity of SdGST and inducing in vitro cytotoxicity of microfilariae. Peripheral blood mononuclear cells (PBMC) from endemic normals upon stimulation with SdGST showed a mixed type of Th1/Th2 response. SdGST immunization clear microfilariae from circulation in S. digitata implanted mastomys.@*CONCLUSIONS@#The heterologous GST could be potentially developed as a vaccine candidate against lymphatic filarial parasite.


Subject(s)
Animals , Antibodies, Helminth , Blood , Antigens, Helminth , Chemistry , Allergy and Immunology , Cattle , Cattle Diseases , Allergy and Immunology , Cell Proliferation , Chromatography, Liquid , Cytokines , Metabolism , Cytotoxicity Tests, Immunologic , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Female , Filariasis , Allergy and Immunology , Filarioidea , Allergy and Immunology , Glutathione Transferase , Chemistry , Allergy and Immunology , Immunoblotting , Male , Mass Spectrometry , T-Lymphocytes , Allergy and Immunology , Vaccination , Methods
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