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1.
Electron. j. biotechnol ; 44: 1-5, Mar. 2020. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1087706

RESUMO

Background: Freeze-drying is known as one of the best methods to preserve bacterial strains. Protectant is the key factor affecting the survival rate of freeze-dried strains. In addition, salinity, bacterial suspension concentration, drying time, and other factors can also affect the survival rate of strains to varying degrees. At present, there are relatively few studies on freeze-drying preservation of marine bacteria. In the present study, we performed the freeze-drying protectant screening and optimized the preservation conditions for Pseudoalteromonas nigrifaciens, which is widely distributed in marine environment. The protective effects of the screened protectants were verified by 18 other marine bacterial strains. Results: The results indicated that the combination of 5.0% (w/v) lactose, 5.0% (w/v) mannitol, 5.0% (w/v) trehalose, 10.0% (w/v) skim milk powder, 0.5% (w/v) ascorbic acid and 0.5% (w/v) gelatin was the best choice for the preservation of P. nigrifaciens. The suggested salinity and concentration of initial cell suspension were 10 g/L NaCl and 1.0 × 109 CFU/mL, respectively. Furthermore, stationary-phase cells were the best choice for the freeze-drying process. The highest survival rate of P. nigrifaciens reached 52.8% when using 5­10% (w/v) skim milk as rehydration medium. Moreover, the other 18 marine strains belonging to Pseudoalteromonas, Vibrio, Photobacterium, Planomicrobium, Edwardsiella, Enterococcus, Bacillus, and Saccharomyces were freezedried under the abovementioned conditions. Their survival rates were 2.3­95.1%. Conclusion: Collectively, our results supported that the protectant mixture and parameters were beneficial for lyophilization of marine bacteria


Assuntos
Preservação Biológica/métodos , Pseudoalteromonas/fisiologia , Liofilização/métodos , Trealose/química , Sobrevivência Celular , Fenômenos Fisiológicos Bacterianos , Dissacarídeos/química , Viabilidade Microbiana , Salinidade , Lactose/química , Manitol/química
2.
Braz. dent. sci ; 23(1): 1-8, 2020. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1049962

RESUMO

Objective: Dental composites developed by using nanotechnology in the field of dentistry are widely used in the treatment of anterior and posterior teeth. This study aimed to investigate the cytotoxic effects of dental composites of different particle size on L929 mouse fibroblast cell line by extract test method in vitro. Material and Methods: Composite samples of 8 x 2 mm diameter were prepared by polymerizing with led light device by using glass mod in a sterile cabinet. Composite samples of which surface areas were calculated according to ISO standards (3 cm2 / ml), were incubated for 24 and 72 hours, at 37 o C. cell viability was assessed by 3-[4,5-dimethylthiazole-2- yl]-2,5-diphenyltetrazolium bromide (MTT) assay and cell death was evaluated by the lactate dehydrogenase (LDH) leakage assay. Results: The 1:1 extracts of the composites at the end of 24 hours (except for nanoceramic composite) showed no toxic effect. When the cell viability results of the 1:1 extracts of the composite samples at the end of 72 hours were statistically analyzed, significant differences were found comparing to the control group (p < 0.05). Conclusion: It was observed that the type and size of the filler were effective on the toxicity of the composites, and the composites containing Bis-GMA, TEGDMA, UDMA and Bis EMA monomers in their organic matrix showed acceptable cell viability (70%) as specified by ISO. However, the composites with PEGDMA and BPA monomers in their organic matrix showed poor cell viability, which is below the acceptable level of 70%, and were found to have a toxic effect. (AU)


Objetivo: As resinas compostas desenvolvidas pela nanotecnologia no campo da odontologia são amplamente utilizadas no tratamento de dentes anteriores e posteriores. Este estudo teve como objetivo investigar os efeitos citotóxicos de resinas compostas de diferentes tamanhos de partículas na linha celular de fibroblastos de camundongos L929 pelo método de teste de extrato in vitro. Material e Métodos: Amostras compostas de 8 x 2 mm de diâmetro foram preparadas por polimerização com dispositivo de luz led usando um molde de vidro em um gabinete estéril. Amostras de resinas cujas áreas de superfície foram calculadas de acordo com os padrões ISO (3 cm2 / ml), foram incubadas por 24 e 72 horas, a 37 o C. A viabilidade celular foi avaliada pelo ensaio de brometo de 3- [4,5-dimetiltiazol-2- il] -2,5-difeniltetrazólio (MTT) e a morte celular foi avaliada pelo ensaio de infiltração de lactato desidrogenase (LDH). Resultados: Os extratos 1: 1 dos compósitos ao final de 24 horas (exceto o composto nanocerâmico) não apresentaram efeito tóxico. Quando os resultados de viabilidade celular dos extratos 1: 1 das amostras compostas ao final de 72 horas foram analisados, estatisticamente, foram encontradas diferenças significativas em relação ao grupo controle (p < 0,05). Conclusão: Observou-se que o tipo e tamanho da carga foram eficazes na toxicidade dos compósitos, e os compósitos contendo os monômeros Bis-GMA, TEGDMA, UDMA e Bis EMA em sua matriz orgânica apresentaram viabilidade celular aceitável (70%) como especificado pela ISO. No entanto, os compósitos com monômeros PEGDMA e BPA em sua matriz orgânica apresentaram baixa viabilidade celular, que está abaixo do nível aceitável de 70%, e foram encontrados como tendo um efeito tóxico. (AU)


Assuntos
Animais , Camundongos , Resinas Compostas/toxicidade , Estética Dentária , Fibroblastos , Técnicas In Vitro , Linhagem Celular , Sobrevivência Celular , Nanopartículas , L-Lactato Desidrogenase/toxicidade
3.
Int. j. morphol ; 37(3): 1132-1141, Sept. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1012409

RESUMO

Spermatogonial stem cells (SSCs) have self-renewal and differentiation capacity essential for sperm production throughout the male reproductive life. The electrospun polycaprolactone/gelatin (PCL/Gel) nanofibrous scaffold mimics important features of the extracellular matrix (ECM), which can provide a promising technique for the proliferation and differentiation of SSCs in vitro. The goal of the present study was to investigate the effects of PCL/Gel nanofibrous scaffold on the propagation and differentiation of neonate mouse SSCs (mSSCs). mSSCs were enzymatically isolated, and the cells were purified by differential plating method and seeded on scaffold. After 2 weeks, viability, colony number and diameter, and expression of specific spermatogonial cell genes were investigated. After mSSCs propagation, the cells were cultivated in a differentiation medium on the scaffold for another 2 weeks, and differentiating cells were analyzed by real-time PCR. The number of mSSC colony (P<0.01) and expression levels of specific spermatogonial genes Plzf and Inga6 (P<0.01) and also differentiation genes c-Kit, Tp1 and Ptm1 (P<0.05) were higher in scaffold group compared with control during the culture period. We conclude that mSSCs can be expanded and can differentiate toward spermatid cells on PCL/Gel nanofibrous scaffold with improved developmental parameters.


Las células madre espermatogónicas (CME) tienen capacidad de auto renovación y diferenciación esenciales para la producción de esperma a lo largo de la vida reproductiva masculina. El «scaffold¼ nanofibroso de policaprolactona / gelatina (PCL / Gel) electrohilado imita características importantes de la matriz extracelular (MEC), que puede proporcionar una técnica prometedora para la proliferación y diferenciación de CME in vitro. El objetivo del presente estudio fue investigar los efectos del «scaffold¼ nanofibroso PCL / Gel en la propagación y diferenciación de CME de ratones neonatos (mSSC). Los mSSC se aislaron enzimáticamente y las células se purificaron mediante un método de siembra diferencial y se sembraron en un «scaffold¼. Después de 2 semanas, se investigaron la viabilidad, el número y el diámetro de las colonias y la expresión de genes específicos de células espermatogónicas. Después de la propagación de mSSC, las células se cultivaron en un medio de diferenciación en el «scaffold¼ durante otras 2 semanas, y las células se analizaron mediante PCR en tiempo real. El número de colonias mSSC (P <0,01) y los niveles de expresión de los genes espermatogónicos específicos Plzf e Inga6 (P <0,01) y también los genes de diferenciación c-Kit, Tp1 y Ptm1 (P <0,05) fueron mayores en el grupo de «scaffold¼ en comparación con el control durante el período de cultivo. Concluimos que los mSSC pueden expandirse y diferenciarse en células espermátidas en un «scaffold¼ de nanofibras PCL / Gel con parámetros de desarrollo mejorados.


Assuntos
Animais , Masculino , Camundongos , Espermatogônias/citologia , Espermatogônias/metabolismo , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Poliésteres/química , Diferenciação Celular/genética , Sobrevivência Celular , Imunofluorescência , Proliferação de Células/genética , Tecidos Suporte , Nanofibras/química , Reação em Cadeia da Polimerase em Tempo Real , Animais Recém-Nascidos
4.
Int. j. morphol ; 37(2): 584-591, June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1002262

RESUMO

Following the success of the highly active antiretroviral therapy, the potential of multidrug combination regimen for the management of cancer is intensely researched. The anticancer effects of curcumin on some human cell lines have been documented. Lopinavir is a FDA approved protease inhibitor with known apoptotic activities. Dysregulated apoptosis is important for the initiation of cancer while angiogenesis is required for cancer growth and development, this study therefore investigated the effects of the combination of lopinavir and curcumin on cell viability, apoptosis and the mRNA expression levels of key apoptotic and angiogenic genes; BAX, BCL2 and VEGF165b in two human cervical cell lines; human squamous cell carcinoma cells - uterine cervix (HCS-2) and transformed normal human cervical cells (NCE16IIA). The two human cervical cell lines were treated with physiologically relevant concentrations of the agents for 120 h following which BAX, BCL2 and VEGF165b mRNA expression were determined by Real Time qPCR. The Acridine Orange staining for the morphological evaluation of apoptotic cells was also performed. The combination of lopinavir and curcumin up-regulated pro-apoptotic BAX and antiangiogenic VEGF165b but down-regulated the mRNA levels of anti-apoptotic BCL2 mRNA in the human squamous cell carcinoma (HCS-2) cells only. The fold changes were statistically significant. Micrographs from Acridine Orange staining showed characteristic evidence of apoptosis in the human squamous cell carcinoma (HCS-2) cells only. The findings reported here suggest that the combination of curcumin and the FDA approved drug-lopinavir modulate the apoptotic and angiogenic pathway towards the inhibition of cervical cancer.


Tras el éxito de la terapia antirretroviral altamente activa, se investiga intensamente el potencial del régimen de combinación de múltiples fármacos para el tratamiento del cáncer. Se han documentado los efectos anticancerígenos de la curcumina en algunas líneas celulares humanas. Lopinavir es un inhibidor de proteasa aprobado por la FDA con actividades apoptóticas conocidas. La apoptosis disrregulada es importante para el inicio del cáncer, mientras que la angiogénesis es necesaria para el crecimiento y desarrollo del cáncer. Por lo tanto, este estudio investigó los efectos de la combinación de lopinavir y curcumina sobre la viabilidad celular, la apoptosis y los niveles de expresión del ARNm de genes apoptóticos y angiogénicos clave: BAX, BCL2 y VEGF165b en dos líneas celulares cervicales humanas; células de carcinoma de células escamosas humanas: cérvix uterino (HCS-2) y células cervicales humanas transformadas (NCE16IIA). Las dos líneas celulares cervicales humanas se trataron con concentraciones fisiológicamente relevantes de los agentes durante 120 horas, después de lo cual la expresión de ARNm de BAX, BCL2 y VEGF165b se determinó mediante qPCR en tiempo real. También se realizó la tinción con naranja de acridina para la evaluación morfológica de células apoptóticas. La combinación de lopinavir y curcumina reguló incrementando BAX proapoptósicos y VEGF165b antiangiogénicos, pero reguló a la baja los niveles de ARNm del BCL2 antiapoptótico en células de carcinoma de células escamosas humanas (HCS-2) únicamente. Los cambios en el pliegue fueron estadísticamente significativos. Las micrografías de la tinción con naranja de acridina mostraron evidencia característica de apoptosis solo en las células del carcinoma de células escamosas humanas (HCS-2). Los hallazgos reportados aquí sugieren que la combinación de curcumina y el fármaco aprobado por la FDA lopinavir modulan la vía apoptótica y angiogénica hacia la inhibición del cáncer cervical.


Assuntos
Humanos , Feminino , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias do Colo do Útero/tratamento farmacológico , Curcumina/farmacologia , Lopinavir/farmacologia , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Proteína X Associada a bcl-2/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Reação em Cadeia da Polimerase em Tempo Real
5.
Rev. ADM ; 76(2): 72-76, mar.-abr. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1000403

RESUMO

Introducción: Los materiales para la obturación retrógrada son diversos. Actualmente, IRM y MTA son las alternativas clínicas más utilizadas, no obstante, es relativamente reciente la introducción de materiales a base de silicatos tricálcicos tal como Biodentine. Objetivo: Determinar la citotoxicidad de fibroblastos del ligamento periodontal humano expuestos a medios de cultivo condicionados con Biodentine, IRM y MTA. Material y métodos: 1 × 103 fibroblastos del ligamento periodontal humano fueron expuestos a medios DMEM/F12 condicionados con MTA, IRM y Biodentine en tres protocolos diferentes. Se realizó un ensayo de MTT para determinar la viabilidad celular a las cero, 24, 48, 72 horas, siete y 14 días. Se realizó una prueba ANOVA (p < 0.05). Resultados: En los tres protocolos con los diferentes medios de cultivo condicionados, la viabilidad de las células fue predominantemente proliferativa; sin embargo, las células expuestas a Biodentine mostraron una tendencia mayor que la MTA o la IRM. Conclusión: Las células expuestas a la Biodentine mostraron un comportamiento proliferativo a los 14 días de análisis. Se debe realizar más investigación a nivel in vivo y clínico para obtener más información sobre la conducta de estos materiales empleados para la obturación retrógrada (AU)


Introduction: The materials for retrograde filling are diverse. Currently, IRM and MTA are the most commonly used clinical alternatives, however, the introduction of materials based on tricalcium silicates such as Biodentine is relatively recent. Objective: To determine the cytotoxicity of human periodontal ligament fibroblasts exposed to culture media conditioned with Biodentine, IRM and MTA. Material and methods: 1 × 103 fibroblasts of the human periodontal ligament were exposed to DMEM/F12 media conditioned with MTA, IRM and Biodentine in 3 different protocols. An MTT assay was performed to determine cell viability at 0, 24, 48, 72 hours, seven and 14 days. An ANOVA test was performed (p < 0.05). Results: In the three protocols with the different conditioned culture media, the viability of the cells was predominantly proliferative, however, the cells exposed to Biodentine showed a higher tendency than the MTA or the IRM. Conclusion: The cells exposed to the Biodentine showed a proliferative behavior at 14 days of analysis. More research should be done at in vivo and clinical level to obtain more information about the behavior of these materials used for retrograde filling (AU)


Assuntos
Humanos , Materiais Restauradores do Canal Radicular/classificação , Materiais Restauradores do Canal Radicular/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Ligamento Periodontal , Obturação Retrógrada , Análise de Variância , Compostos de Cálcio , Compostos de Alumínio , Meios de Cultura , Fibroblastos
6.
Biosci. j. (Online) ; 35(2): 609-619, mar./apr. 2019. graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1048614

RESUMO

The tubers of three orchidaceous plants, includingPleione bulbocodioides (Franch.) Rolfe, have been used as 'Shan-Ci-Gu' in traditional Chinese medicine for the treatment of bacterial infections and cancers for thousands of years. In this study, the effects of an acetoacetate (EtOAc) extract of P. bulbocodioides on the cell viability and apoptosis of THP-1 (human acute monocytic leukemia cell line) cells and its interaction with possible apoptotic pathways were investigated. THP-1 cells were treated with the EtOAc extract of P. bulbocodioides at different concentrations. The results showed that THP-1 cell viability was significantly inhibited by the EtOAc extract ofP. bulbocodioides with an IC50 of 51.37±2.68 µ g/ mL at 24 h. The examination of cytotoxic effects on healthy cells showed that the EtOAc extract of P. bulbocodioidesdid not show any effect on healthy Vero cells. Selectivity indexes were greater than 15.57, suggesting that the EtOAc extract of P. bulbocodioides had selective toxicity against THP-1 cells. The results of annexin V-FITC/PI and DAPI staining showed that the EtOAc extract of P. bulbocodioides induced cell apoptosis in a dose-dependent manner. The apoptotic rate was increased in the treatment groups compared with that in the control group (P<0.05). The distribution of cells in the G2 phase of the cell cycle increased along with typical cell apoptosis-induced morphological changes. The levels of the pro-apoptotic proteins Bax, cleaved PARP and cleaved caspase-3 increased with increasing concentration of acetoacetate extract of P. bulbocodioides, while the anti-apoptosis protein Bcl-2 was downregulated. Cyt c and AIF, which are characteristic proteins of the mitochondria-regulated intrinsic apoptosis pathway, also increased in the cytosol with increasing concentrations of the EtOAc extract of P. bulbocodioides. These results showed that the EtOAc extract of P. bulbocodioidessignificantly inhibits cell viability and induces cell apoptosis in the human leukemia cell line THP-1 through a mitochondria-regulated intrinsic apoptotic pathway


Os tubérculos de três plantas orquidáceas, incluindo Pleione bulbocodioides (Franch.) Rolfe, têm sido usados como "Shan-Ci-Gu" na medicina tradicional chinesa para o tratamento de infecções bacterianas e cânceres por milhares de anos. Neste estudo, os efeitos de um extrato de acetoacetato (EtOAc) de P. bulbocodioides na viabilidade celular e apoptose de células THP-1 (linhagem celular de leucemia monocítica aguda humana) e sua interação com possíveis vias apoptóticas foram investigados. As células THP-1 foram tratadas com o extrato EtOAc de P. bulbocodioides em diferentes concentrações. Os resultados mostraram que a viabilidade das células THP-1 foi significativamente inibida pelo extrato EtOAc de P. bulbocodioides com IC50 de 51,37 ± 2,68 µ g/mL às 24 h. O exame dos efeitos citotóxicos em células saudáveis mostrou que oextrato de EtOAc de P. bulbocodioides não mostrou nenhum efeito sobre células Vero saudáveis. Os índices de seletividade foram maiores que 15,57, sugerindo que o extrato de EtOAc de P. bulbocodioides teve toxicidade seletiva contra as células THP-1. Os resultados da coloração da anexina V-FITC/PI e DAPI mostraram que o extrato de EtOAc de P. bulbocodioides induziu a apoptose celular de maneira dose-dependente. A taxa de apoptose foi aumentada nos grupos de tratamento em comparação com o grupo controle (P <0,05). A distribuição de células na fase G2 do ciclo celular aumentou juntamente com alterações morfológicas típicas induzidas pela apoptose celular. Os níveis das proteínas pró-apoptóticas Bax, PARP clivada e caspase-3 clivada aumentaram com o aumento da concentração do extrato acetoacetato de P. bulbocodioides, enquanto a proteína anti-apoptose Bcl-2 foi regulada negativamente. Cyt c e AIF, que são proteínas características da via de apoptose intrínseca regulada por mitocôndrias, também aumentaram no citosol com concentrações crescentes do extrato de EtOAc de P. bulbocodioides. Estes resultados mostraram que o extrato de EtOAc de P. bulbocodioides inibe significativamente a viabilidade celular e induz a apoptose na linha celular de leucemia humana THP-1 através de uma via apoptótica intrínseca regulada por mitocôndrias.


Assuntos
Leucemia , Sobrevivência Celular , Apoptose , Orchidaceae , Mitocôndrias , Tubérculos , Células THP-1 , Medicina Tradicional Chinesa , Acetoacetatos
8.
Braz. J. Pharm. Sci. (Online) ; 55: e18063, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1039055

RESUMO

Cymbopogon citratus and C. nardus are noteworthy among the several existing plant species displaying medicinal properties, due to the potential pharmacological activity of these species, including antiviral, antibacterial, antifungal and anti-trypanosomal activities. The objective of this study was to carry out in vitro toxicity tests of plant extracts from both species and analyze potential antiviral activity against Human mastadenovirus serotype 5 (HAdV-5). Two cell lines (A549 and VERO) were used and mitochondrial and lysosomal viability were determined by the MTT and neutral red assay, respectively, after two exposure times (24 hours and six days). The aim of these assays was to counteract the behavior of the extracts against the different cell lines and determine their non-toxic concentration range, in order to evaluate possible antiviral activity against HAdV-5. Plaque reduction and inhibition index of viral titer assays were performed using the maximum non-cytotoxic concentrations (MNCC) of each extract. The results indicate MNCC at 625 µg/mL for all extracts, except for Cymbopogon nardus obtained with 80% ethanol (CN80), which showed toxicity at concentrations higher than 312.5 µg/mL. CN80 was the only extract that displayed potential activity against HAdV-5, at a concentration of 75 µg/mL, becoming a candidate for extract fraction purification and/or the isolation of substances related to the observed antiviral activity


Assuntos
Extratos Vegetais/análise , Mastadenovirus/isolamento & purificação , Cymbopogon/toxicidade , Antivirais/análise , Técnicas In Vitro , Sobrevivência Celular
9.
Acta cir. bras ; 34(2): e201900210, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989058

RESUMO

Abstract Purpose: To analyze aspects of the biomodulating effect of light in biological tissues, bone cells from surgical explants of the femur of rats were irradiated with low intensity laser. Methods: Bone cells were cultured and irradiated with LASER light (GaAlAs). Growth, cell viability, mineralized matrix formation, total protein dosage, immunostimulatory properties, cytochemical analysis, gene expression of bone proteins were examined using live cell imaging and cell counting by colorimetric assay. The gene expression of: alkaline phosphatase (ALP), type 1 collagen, osteocalcin and osteopontin through the real-time polymerase chain reaction. Results: At 8 days, the viability of the irradiated culture was 82.3% and 72.4% in non-irradiated cells. At 18 days, the cellular viability (with laser) was 77.42% and 47.62% without laser. At 8 days, the total protein concentration was 21.622 mg / mol in the irradiated group and 16, 604 mg / mol in the non-irradiated group and at 18 days the concentration was 37.25 mg / mol in the irradiated group and 24, 95 mg / mol in the non-irradiated group. Conclusion: The laser interfered in the histochemical reaction, cell viability, matrix mineralization, and maintained the cellular expression of proteins


Assuntos
Animais , Ratos , Osteoblastos/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Fatores de Tempo , Células Cultivadas , Ratos Wistar , Relação Dose-Resposta à Radiação
10.
Bol. latinoam. Caribe plantas med. aromát ; 17(6): 575-582, nov. 2018. ilus
Artigo em Inglês | LILACS | ID: biblio-1007341

RESUMO

The skin is the largest organ of the human body and its main function is to protect it from the external environment. It is exposed to injuries that require a rapid healing process to recover its functionality. Microorganisms inhabit the skin, which makes up the normal microbial flora, but in situations of injury they can cause infections that slow down the regeneration process. Therefore, there is a great interest in the development of alternative methods to accelerate the regeneration process and prevent infections. In this work, the efficacy of flavonoid 3-O-methylgalangine and the terpenic derivative Filifolinone and its mixtures, isolated from plants of the genus Heliotropium, on the stimulation of cell proliferation was evaluated. The results showed that the mixtures stimulated proliferation and migration in MA104 cells mainly due to the presence of Filifolinone, that together with the known antibacterial activity of 3-O-methylgalangine, opens new alternatives for the use of natural compounds in healing processes.


La piel es el órgano más grande del cuerpo humano y su función principal es protegerla del entorno externo. Está expuesta a lesiones que requieren un proceso de curación rápido para recuperar su funcionalidad. Los microorganismos que habitan en la piel, constituyen la flora microbiana normal, pero en situaciones de lesión pueden causar infecciones que retardan el proceso de regeneración. Por lo tanto, existe un gran interés en el desarrollo de métodos alternativos para acelerar el proceso de regeneración y prevenir infecciones. En este trabajo, se evaluó la eficacia del flavonoide 3-O-metilgalangina y el derivado terpénico Filifolinona y sus mezclas, aisladas de plantas del género Heliotropium, en la estimulación de la proliferación celular. Los resultados mostraron que las mezclas estimularon la proliferación y la migración en las células MA104 debido principalmente a la presencia de Filifolinona, que junto con la actividad antibacteriana conocida de la 3-O-metilgalangina, abre nuevas alternativas para el uso de compuestos naturales en los procesos de curación.


Assuntos
Terpenos/farmacologia , Flavonoides/farmacologia , Heliotropium , Proliferação de Células/efeitos dos fármacos , Terpenos/química , Cicatrização , Flavonoides/química , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/efeitos dos fármacos
11.
Bol. latinoam. Caribe plantas med. aromát ; 17(6): 566-574, nov. 2018. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1007336

RESUMO

The composition of the essential oil obtained by hydrodistillation from Minthostachys mollis Griseb (Lamiaceae) aerial parts was determined by GC and GC/MS. Menthone (13.2%), pulegone (12.4%), cis-dihydrocarvone (9.8%) and carvacrol acetate (8.8%) were the main essential oil components. The cytotoxic activity of the essential oil was in vitro measured using the MTT colorimetric assay. IC50 values were calculated on healthy non-tumor cells (HEK-293) and three human cancer cell lines (T24, DU-145 and MCF-7). In such latter cells, the estimated values were around 0.2 mg/mL. In addition, the antioxidant activity was determined by interaction with the stable free radical 2,2"-diphenyl-1-picrylhydrazyl. The essential oil was almost devoid of antioxidant activity indicating that its anti-proliferative action relies on other unknown mechanism.


La composición del aceite esencial obtenido por hidrodestilación a partir de partes aéreas de Minthostachys mollis Griseb (Lamiaceae) se determinó mediante GC y GC/MS. Mentona (13.2%), pulegona (12.4%), junto con cis-dihidrocarvona (9.8%) y acetato de carvacrol (8.8%) fueron los principales componentes del aceite esencial. La actividad citotóxica del aceite esencial se midió in vitro utilizando el ensayo colorimétrico MTT tanto en células sanas no tumorales (HEK-293) como en tres líneas celulares de cáncer humano (T24, DU-145 y MCF-7). Los valores de IC50 calculados fueron de alrededor de 0.2 mg/mL. Además, se determinó la actividad antioxidante por su interacción con el radical libre 2,2"-difenil-1-picrilhidrazilo. El aceite esencial tiene baja actividad antioxidante, lo que indica que su acción antiproliferativa depende de otro mecanismo desconocido.


Assuntos
Óleos Voláteis/farmacologia , Lamiaceae , Linhagem Celular Tumoral/efeitos dos fármacos , Antioxidantes/farmacologia , Peru , Picratos , Terpenos/análise , Bioensaio , Compostos de Bifenilo , Calorimetria , Óleos Voláteis/química , Sobrevivência Celular/efeitos dos fármacos , Depuradores de Radicais Livres , Cromatografia Gasosa-Espectrometria de Massas , Antioxidantes/química
12.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 55(3): e145873, Outubro 25, 2018. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-969239

RESUMO

Protocols for cooling or freezing goat semen usually recommend centrifugation for seminal plasma removal. However, little is known about the effect of this process on goat sperm viability and functionality. The present study evaluated the effects of centrifugation force on the plasma membrane, acrosomes, and DNA integrity of goat semen. Four ejaculates from each of the four different Anglo Nubian male goats were used. Semen samples were obtained using artificial vagina, and immediately after collection, ejaculates were diluted using Ringer's sodium lactate solution and split into three groups: Control (CG, without centrifugation), G1 (centrifugation 600 x g/10 min), G2 (centrifugation 1200 x g/10 min). After centrifugation, seminal plasma was removed, the sperm pellets were resuspended using Tris-egg yolk extender (80 x 106 spermatozoa/mL) and the sperm morphology was analyzed. Samples were cooled at 5°C for 5, 24, 36, and 48 h and then sperm plasma membrane and acrosome integrity (PMAI, %) and sperm DNA fragmentation index (SDF, %) were evaluated at each time-point, using a flow cytometer. Additionally, sperm movement was determined using computer semen analysis (CASA) after 5, 24, and 48 h of refrigeration period. The semen centrifugation did not induce additional sperm morphology defect or reduction in sperm kinetics in the experimental groups. Differences were not observed (p > 0.05) in PMAI and SDF among different groups, in any of each time-point of the cooling process. In conclusion, centrifugation, even at high speeds, did not affect goat sperm integrity and functionality when submitted to refrigeration process. (AU)


A maior parte dos protocolos de refrigeração e criopreservação do sêmen caprino recomenda o uso de centrifugação para remoção do plasma seminal. No entanto, não existe consenso sobre o risco que esse tipo de processamento pode ocasionar à viabilidade espermática. Nesse contexto, o presente trabalho investigou os possíveis efeitos deletérios da centrifugação sobre a integridade estrutural e DNA de espermatozoides caprinos. Para a pesquisa foram selecionados quatro reprodutores para colheita de sêmen (n = 4 ejaculados/bode). Cada ejaculado foi fracionado em três alíquotas iguais, diluídas em ringer e divididas em três grupos: Controle (GC, não centrifugado), G1 (centrifugação a 600 g/10 minutos) e G2 (centrifugação a 1200 g/10 minutos). As amostras seminais por grupo foram diluídas em meio Tris gema respeitando-se a concentração final de 80 milhões de espermatozoides/mL e foram submetidas à avaliação de morfologia espermática. Todas as amostras foram acondicionadas a 5°C, sendo analisadas nos momentos 5, 24, 36 e 48 horas do processo de refrigeração por meio da avaliação da integridade de membrana plasmática e acrossomal (MPAI, %) e índice de fragmentação de DNA (IDF, %). Adicionalmente, a cinética espermática foi avaliada com o emprego de um sistema computadorizado de análise (CASA) nos momentos 5, 24 e 48 horas da refrigeração. A centrifugação não induziu a manifestação de defeitos morfológicos ou redução significativa da cinética de espermatozoides caprinos. Não foram observadas diferenças para a integridade de membrana plasmática e para o índice de fragmentação de DNA quando comparados, respectivamente, GC, G1 e G2 em cada um dos quatro momentos experimentais. Conclui-se que mesmo quando empregadas altas forças de rotação não ocorre lesão à ultraestrutura dos espermatozoides caprinos submetidos ao processo de refrigeração.(AU)


Assuntos
Animais , Espermatozoides/classificação , Ruminantes/embriologia , Membrana Celular , Sobrevivência Celular
13.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 16(2): 12-20, Ago. 2018. ilus
Artigo em Espanhol | LILACS, BDNPAR | ID: biblio-997947

RESUMO

Las plantas de uso en medicina tradicional constituyen una fuente importante de compuestos con actividad inmunomoduladora; entre ellas las especies del género Baccharis, conocidas popularmente como "Jaguareteka´a" en nuestro país, son ampliamente empleadas. En este estudio se evaluó la actividad inmunomoduladora de extractos metanólicos de tres especies del género Baccharis (B. trimera, B. notosergilay B. punctulata) sobre la proliferación de células mononucleares humanas de sangre periférica. Los extractos de las tres especies estudiadas estimularon la proliferación de las células mononucleares. Específicamente, el extracto de B. notosergila estimuló la proliferación celular a todas las concentraciones probadas (5, 10, 25 y 50 µg/mL), mientras que los extractos de B. trimera y B. punctulata mostraron este efecto a 5 y 10 µg/mL. Además, por presentar mayor inducción de la proliferación, se realizó un fraccionamiento con diferentes solventes del extracto metanólico de B. notosergila y B. punctulata. La fracción de acetato de etilo de ambos extractos vegetales aumentó la proliferación celular, sugiriendo que compuestos de polaridad media son los responsables de esta actividad. Estos resultados demuestran que los extractos de B. trimera, B. notosergila y B. punctulata poseen actividad inmunomoduladora sobre células mononucleares humanas y servirán de base a otros estudios para determinar el o los componentes activos de los extractos sobre el sistema inmune(AU)


Plants used in traditional medicine are an important source of compounds with immunomodulatory activity. Species of the genus Baccharis, popularly known as "Jaguareteka'a" in our country, are used in folk medicine for the treatment of liver, gastrointestinal, inflammatory and infectious diseases. In this study, we evaluated the immunomodulatory activity of methanolic extracts of three species of the genus Baccharis (B. trimera, B. notosergila and B. punctulata) on the proliferation of human peripheral blood mononuclear cells. Extracts of the three species studied stimulated the proliferation of mononuclear cells. The extract of B. notosergila stimulated cell proliferation at all concentrations tested, while extracts of B. trimera and B. punctulata stimulated at 5 and 10 µg/mL. In addition, we carried out a separation with different solvents of the methanolic extract of B. notosergila and B. punctulata. The ethyl acetate fraction of both plant extracts induced the proliferation of immune cells. These results show that the extracts of B. trimera, B. notosergila and B. punctulata had immunomodulatory activity on human mononuclear cells. Future work will be required to identify the components responsible for the activity on the immune system(AU)


Assuntos
Células Sanguíneas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Baccharis , Proliferação de Células/efeitos dos fármacos , Imunomodulação/efeitos dos fármacos , Plantas Medicinais , Linfócitos/efeitos dos fármacos , Sobrevivência Celular
14.
Int. j. morphol ; 36(2): 435-440, jun. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-954133

RESUMO

Parkinson's disease (PD) is described as a neurological condition, resulting from continuous degeneration of dopaminergic neurons. Currently, most treatments for neurodegenerative diseases are palliative. In traditional Iranian medicine, Citrus aurantium flower extract is used to treat some neural diseases, such as sleep disorders and anxiety. The tendency towards the use of medicinal herbs for the treatment of diseases (eg, seizure) is growing. Accordingly, we evaluated the antioxidant effects of C. aurantium flowers and analyzed their protective effects against 6-hydroxydopamine (6-OHDA)-mediated oxidative stress. In this study, 150 mM of 6-OHDA was used to induce cellular damage. Also, MTT assay was performed to analyze cellular viability. Fluorescence spectrophotometry was performed to measure the intracellular reactive oxygen species (ROS) and calcium levels. Based on the findings, 6-OHDA could reduce cell viability. We also analyzed the effects of C. aurantium against neurotoxicity. The intracellular levels of ROS and calcium greatly improved in cells exposed to 6-OHDA. SH-SY5Y cell incubation with C. aurantium (400 and 600 mg/mL) induced protective effects and decreased the biochemical markers of cell apoptosis. According to the findings, C. aurantium showed protective effects against neurotoxicity, caused by 6-OHDA; these protective properties were accompanied by antiapoptotic features. According to the findings, it seems that hydromethanolic C. aurantium extract can be used to prevent seizures.


La enfermedad de Parkinson (EP) se describe como una afección neurológica que resulta de la degeneración continua de las neuronas dopaminérgicas. Actualmente, la mayoría de los tratamientos para las enfermedades neurodegenerativas son paliativos. En la medicina tradicional iraní, el extracto de flor de Citrus aurantium se usa para tratar algunas enfermedades neurológicas, como los trastornos del sueño y la ansiedad. La tendencia hacia el uso de las medicinas para el tratamiento de enfermedades (por ejemplo, convulsiones) está creciendo. Por consiguiente, el objetivo de este trabajo consistió en evaluar los efectos antioxidantes de las flores de C. aurantium y analizar sus efectos protectores contra el estrés oxidativo mediado por la 6- hidroxidopamina (6-OHDA). En este estudio, se usó 150 mM de 6-OHDA para inducir daño celular. Además, se realizó un ensayo de MTT para analizar la viabilidad celular. La espectrofotometría de fluorescencia se realizó para medir las especies reactivas de oxígeno (ROS) intracelulares y los niveles de calcio. En base a los hallazgos, 6-OHDA podría reducir la viabilidad celular. También analizamos los efectos de C. aurantium contra la neurotoxicidad. Los niveles intracelulares de ROS y calcio se expandieron a las células expuestas a 6-OHDA. La incubación de células SH-SY5Y con C. aurantium (400 y 600 mg / ml) indujo efectos protectores y disminuyó los marcadores bioquímicos de la apoptosis celular. De acuerdo con los hallazgos, C. aurantium mostró efectos protectores contra la neurotoxicidad, causada por 6-OHDA; estas propiedades protectoras fueron acompañadas por características antiapoptóticas. Según los hallazgos, parece que el extracto hidrometanólico de C. aurantium se puede usar para prevenir las convulsiones.


Assuntos
Humanos , Doença de Parkinson , Extratos Vegetais/farmacologia , Citrus/química , Antioxidantes/farmacologia , Espectrometria de Fluorescência , Sobrevivência Celular/efeitos dos fármacos , Citrus , Western Blotting , Espécies Reativas de Oxigênio , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fármacos Neuroprotetores , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Hidroxidopaminas/toxicidade , Neuroblastoma
15.
Acta cir. bras ; 33(6): 533-541, June 2018. graf
Artigo em Inglês | LILACS | ID: biblio-949351

RESUMO

Abstract Purpose: To investigate the specific molecular mechanisms and effects of curcumin derivative J147 on diabetic peripheral neuropathy (DPN). Methods: We constructed streptozotocin (STZ)-induced DPN rat models to detected mechanical withdrawal threshold (MWT) in vivo using Von Frey filaments. In vitro, we measured cell viability and apoptosis, adenosine 5'-monophosphate-activated protein kinase (AMPK) and transient receptor potential A1 (TRPA1) expression using MTT, flow cytometry, qRT-PCR and western blot. Then, TRPA1 expression level and calcium reaction level were assessed in agonist AICAR treated RSC96cells. Results: The results showed that J147reduced MWT in vivo, increased the mRNA and protein level of AMPK, reduced TRPA1 expression and calcium reaction level in AITCR treated RSC96 cells, and had no obvious effect on cell viability and apoptosis. Besides, AMPK negative regulated TRPA1 expression in RSC96 cells. Conclusions: J147 could ameliorate DPN via negative regulation AMPK on TRPA1 in vivo and in vitro. A curcumin derivative J147might be a new therapeutic potential for the treatment of DPN.


Assuntos
Animais , Masculino , Curcumina/análogos & derivados , Curcumina/farmacologia , Neuropatias Diabéticas/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Canal de Cátion TRPA1/efeitos dos fármacos , Fatores de Tempo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Western Blotting , Cálcio/análise , Reprodutibilidade dos Testes , Apoptose/efeitos dos fármacos , Estreptozocina , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Proteínas Quinases Ativadas por AMP/análise , Reação em Cadeia da Polimerase em Tempo Real , Canal de Cátion TRPA1/análise , Microscopia de Fluorescência
16.
Int. j. morphol ; 36(2): 454-459, jun. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-954136

RESUMO

Berberis darwinii Hook es una especie que habita el sur de Chile y la Patagonia, utilizada por la etnia mapuche para el tratamiento de procesos inflamatorios, estados febriles y dolor de estomacal. El propósito del siguiente estudio fue evaluar in vitro las propiedades del extracto total y de alcaloides de raíz de B. darwinii sobre viabilidad celular y la translocación del factor nuclear NF-kB en línea celular RAW 264.7. Se observó que los extractos no afectan negativamente la viabilidad en las células e inhibieron la translocación del factor nuclear NF-kB asociado a la modulación de la inflamación solo frente al extracto total. Estos resultados indicarían que B. darwinii podría inhibir algunos mecanismos específicos de la defensa celular al modular la translocación de NF- kB.


Berberis darwinii Hook is a species that inhabits southern Chile and Patagonia, used by the Mapuche ethnic group for the treatment of inflammatory processes, febrile states and stomach pain. The purpose of the following study was to evaluate in vitro the properties of the total extract and alkaloids of the root of B. darwinii on cell viability and the translocation of the nuclear factor NF-kB in cell line RAW 264.7. It was observed that the extracts did not negatively affect the viability in the cells and inhibited the translocation of the nuclear factor NF-kB associated with the modulation of inflammation only against the total extract. These results indicate that B. darwinii could inhibit some specific mechanisms of cell defense by modulating the translocation of NF-kB.


Assuntos
Extratos Vegetais/farmacologia , NF-kappa B/efeitos dos fármacos , Berberis , Células RAW 264.7/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Imunofluorescência , Raízes de Plantas , Metanol , Alcaloides/farmacologia , Citometria de Fluxo , Fatores Imunológicos/farmacologia
17.
Rev. chil. endocrinol. diabetes ; 11(2): 47-53, abr. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-914719

RESUMO

Introduction: The Calcium Sensing Receptor (CaSR) is expressed in human fat cells, and its stimulation may be associated with adipose tissue dysfunction. The multisystemic character of obesity and the search of deepening the scope of the activation of CaSR in this disorder allows us to study the response of this protein in tissues that differ from adipose. Objective: To evaluate the effect of CaSR activation on the expression of lipogenic genes in a model of excess glucose and fatty acids in HepG2 human liver cells. Materials and methods: The effect of the calcimimetic cinacalcet (allosteric agonist of CaSR) on the content of triglycerides (fluorimetry) in a model of glucose supply and on the expression of lipogenic genes (qPCR) in hyperglycemia and hyperlipidemia conditions in the Liver cell line HepG2. Results: Cinacalcet, glucose (25 mM) and oleic acid (0.6 mM) did not affect cell viability. Activation of CaSR in the presence of glucose failed to increase the intracellular triglyceride content at 72 hours. Under these conditions, no response was observed for the factors coding for lipogenic genes (SREBP1c and FAS) at 24 hours of stimulation with cinacalcet in the liver cells. In the case of the over supply of fatty acids, the HepG2 cells did not show a variation in the gene expression of the DGAT enzymes after exposure to cinacalcet. Conclusion:Under conditions of glucose exposure, cinacalcet did not show a response in the triglyceride content, nor in the expression of genes related to hepatic lipogenesis. Therefore, stimulation of CaSR would not be associated with hepatic steatosis in HepG2 cells exposed to glucose.


Assuntos
Humanos , Receptores de Detecção de Cálcio , Lipogênese , Células Hep G2 , Sobrevivência Celular , Reação em Cadeia da Polimerase em Tempo Real
18.
Acta cir. bras ; 33(3): 223-230, Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886270

RESUMO

Abstract Purpose: To investigate the impact of different hypoxia reoxygenation (HR) times on autophagy of rat cardiomyocytes (H9C2). Methods: Rat cardiomyocytes were randomly divided into normal control group (group A), hypoxia group (group B), 2 h HR group (group C), 12 h HR group (group D), and 24 h HR group (group E). LC3 II/LC3 I was determined via western blotting, and cell viabilities of cardiomyocytes were measured using methyl thiazolyl tetrazolium (MTT) assay. Results: Cell viabilities in HR model groups were significantly lower than those of group A (P<0.05). LC3 II/LC3 I levels in groups B to D were significantly higher than those of group A (P<0.05), and group D showed the highest LC3 II/LC3 I levels. Cell viabilities in groups B to D were significantly lower than those of group A (P<0.05), with group D showing the lowest cell viabilities (P<0.05). Conclusions: Hypoxia can induce autophagy in rat cardiomyocytes, which can be further activated by reoxygenation; most notable after 12 h. Hypoxia-induced cell injury can be aggravated by reoxygenation. The lowest cell viability was observed at 12 h after reoxygenation; however, cell viability can be recovered after 24 h.


Assuntos
Animais , Ratos , Autofagia/fisiologia , Hipóxia Celular/fisiologia , Sobrevivência Celular/fisiologia , Apoptose/fisiologia , Proteínas Associadas aos Microtúbulos/fisiologia , Fatores de Tempo , Distribuição Aleatória , Linhagem Celular , Miócitos Cardíacos/citologia
19.
Mem. Inst. Oswaldo Cruz ; 113(2): 102-110, Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894895

RESUMO

BACKGROUND In a screen of extracts from plants and fungi to detect antileishmanial activity, we found that the ethyl acetate extract of the fungus Nectria pseudotrichia, isolated from the tree Caesalpinia echinata (Brazilwood), is a promising source of bioactive compounds. OBJECTIVES The aims of this study were to isolate and determine the chemical structures of the compounds responsible for the antileishmanial activity of the organic extract from N. pseudotrichia. METHODS Compounds were isolated by chromatographic fractionation using semi-preparative high-performance liquid chromatography, and their chemical structures were determined by analytical and spectral data and by comparison with published data. The antileishmanial activity of the isolated compounds was evaluated in intracellular amastigote forms of Leishmania (Viannia) braziliensis expressing firefly luciferase as reporter gene, and cytotoxicity was determined in Vero and THP-1 mammalian cell lines by MTT assay. FINDINGS Fractionation of the extract yielded seven compounds: 10-acetyl trichoderonic acid A (1), 6′-acetoxy-piliformic acid (2), 5′,6′-dehydropiliformic acid (3), piliformic acid (4), hydroheptelidic acid (5), xylaric acid D (6), and cytochalasin D (7). Compounds 1, 2 and 3 are reported here for the first time. Compounds 1, 2, and 5 were more active, with IC50 values of 21.4, 28.3, and 24.8 µM, respectively, and showed low toxicity to Vero and THP-1 cells. MAIN CONCLUSIONS N. pseudotrichia produces secondary metabolites that are more toxic to intracellular amastigote forms of L. (V.) braziliensis than to mammalian cells.


Assuntos
Leishmania braziliensis/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Testes de Toxicidade , Caesalpinia/microbiologia , Sobrevivência Celular , Chlorocebus aethiops , Concentração Inibidora 50
20.
Braz. oral res. (Online) ; 32: e003, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-889476

RESUMO

Abstract The aim of this study was to investigate the viability of human dental pulp cells from extracted teeth kept at standard room temperature and atmospheric pressure for different periods of time. Twenty-one healthy permanent teeth were used. They were divided into five groups according to the expected time from extraction to processing. One group was tested immediately after extraction; the other groups were each tested at one of the following time points: 30 minutes, 1 hour, 2 hours, and 5 hours post-extraction. Cell morphology was analysed by light microscopy; cell proliferation was analysed using MTT assay and by counting the viable cells in a haemocytometer. Similar results were observed in all groups (p < 0.05). A delay of up to five hours for tooth processing and tissue collection does not preclude the establishment of dental pulp cell cultures, affect the morphology of these cells, or reduce their proliferative potential.


Assuntos
Humanos , Técnicas de Cultura de Células/métodos , Polpa Dentária/citologia , Extração Dentária , Análise de Variância , Contagem de Células , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Meios de Cultura , Reprodutibilidade dos Testes , Sais de Tetrazólio , Tiazóis , Fatores de Tempo , Preservação de Tecido/métodos
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