Consulta: subjectFacets:"Aspergillus nidulans"
Registros recuperados: 16
Data/hora: 08/06/2024 08:47:26

An investigation of the nuclei of hülle cells of Aspergillus nidulans
Provedor de dados: 74
Autores: Carvalho,Marcos D.F.; Baracho,Marta S.; Baracho,Ivanhoé R.
Certain species of fungi of the genus Aspergillus produce a type of cells around the cleistothecium that are called hülle cells. To facilitate the analysis of the formation of these cells, an Aspergillus nidulans strain with high hülle cell production was obtained. Hülle cells from this strain were allowed to grow on dialysis membranes, where it was possible to observe their nuclei. The material was fixed with Carnoy, hydrolyzed with HCl and stained with Giemsa. Several nuclei approximately equal in size to the nuclei of hyphae and conidia were observed during the phase of hülle cell formation. The formation of a macronucleus measuring approximately 3.1 mum was observed in mature hülle cells. To compare the DNA amount, hülle cells and conidia of the CH-89...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus nidulans; Hülle cell; Macronuclei in fungi; Nuclei of A. nidulans; Macronuclei in hülle cell.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572002000400019

Increase in mitotic recombination in diploid cells of Aspergillus nidulans in response to ethidium bromide
Provedor de dados: 74
Autores: Becker,Tânia C.A.; Chiuchetta,Simone J.R.; Baptista,Francielle; Castro-Prado,Marialba A.A. de.
Ethidium bromide (EB) is an intercalating inhibitor of topoisomerase II and its activities are related to chemotherapeutic drugs used in anti-cancer treatments. EB promotes several genotoxic effects in exposed cells by stabilising the DNA-enzyme complex. The recombinagenic potential of EB was evaluated in our in vivo study by the loss of heterozygosity of nutritional markers in diploid Aspergillus nidulans cells through Homozygotization Index (HI). A DNA repair mutation, uvsZ and a chromosome duplication DP (II-I) were introduced in the genome of tested cells to obtain a sensitive system for the recombinagenesis detection. EB-treated diploid cells had HI values significantly greater than the control at both concentrations (4.0 x 10-3 and 5.0 x 10-3 mM)....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antineoplastic drug; Aspergillus nidulans; Ethidium bromide; Intercalating agent; Mitotic crossing over.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000300026

An analysis of the spontaneous mutation rate measurement in filamentous fungi
Provedor de dados: 74
Autores: Baracho,Marta S.; Baracho,Ivanhoé R.
Mutations related to gene methG1 of Aspergillus nidulans were analyzed, in order to study a mathematical model for the determination of the mutation rate per nucleus per generation, in filamentous fungi. A replica plating technique was used to inoculate, in a single operation, 26 colonies of the strain, into Petri dishes containing culture medium, and the nine central colonies were analyzed for size and number of conidia in each colony. Using this technique, several central colonies were analyzed with regard to the appearance of mutation, and the number and type of reversions were determined for each colony. The frequencies obtained for each reversion were analyzed, in order to verify if their distribution was in accordance with that of Greenwood and Yule....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus nidulans; Mutation rate; Spontaneous mutation; Fungi; Filamentous fungi.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000100014

A glycoprotein with anti-inflammatory properties secreted by an Aspergillus nidulans modified strain
Provedor de dados: 80
Autores: Queiroz,J. C. F.; Teixeira,C. F. P.; Lebrun,I.; Spencer,P. J.; Zucchi,T. M. A. D.
Total RNA from lipopolysaccharide (LPS)-stimulated rat macrophages used to treat protoplasts from an Aspergillus nidulans strain originated the RT2 regenerated strain, whose culture supernatant showed anti-inflammatory activity in Wistar rats. The protein fraction presenting such anti-inflammatory activity was purified and biochemically identified. The screening of the fraction responsible for such anti-inflammatory property was performed by evaluating the inhibition of carrageenan-induced paw edema in male Swiss mice. Biochemical analyses of the anti-inflammatory protein used chromatography, carbohydrates quantification of the protein sample, amino acids content analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Total sugar...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus nidulans; Protein purification and characterization; Glycoprotein; Anti-inflammatory activity.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992007000200010

Evaluación tóxica y genotóxica del extracto fluido de Ocimum gratissimum L.
Provedor de dados: 98
Autores: Blanco Hernández,Neylim; Ramos Ruiz,Alberto; Vizoso Parra,Ángel.
Se evaluó la toxicidad aguda y la actividad genotóxica del extracto fluido de hojas de Ocimum gratissimum L. a través de 2 sistemas de ensayo a corto plazo, uno in vitro con la cepa D-30 de Aspergillus nidulans y otro in vivo, el ensayo de micronúcleos en médula ósea de ratón. La toxicidad aguda del extracto quedó demostrada por la mortalidad observada que alcanzó el 50 % de los animales en la dosis 3g/kg, que fue dosis dependiente. Se encontró una respuesta genotóxica poco acentuada del extracto fluido al 30 % de O. gratissimum. Los resultados permitieron concluir que este extracto mostró efectos tóxicos agudos y signos histológicos de hepatotoxicidad y nefrotoxicidad y no resultó genotóxico sobre la cepa D-30 de Aspergillus nidulans en el ensayo de...
Tipo: Journal article
Palavras-chave: Ocimum gratissimum L; Orégano cimarrón; Aspergillus nidulans; Ensayo de micronúcleos; Toxicidad aguda; Genotoxicidad.
Ano: 2006
URL: http://scielo.sld.cu/scielo.php?script=sci_arttext&pid=S1028-47962006000100003

Evaluación tóxica y genotóxica del extracto fluido de Piper auritum H.B.K.
Provedor de dados: 98
Autores: Blanco Hernández,Neylim; Ramos Ruiz,Alberto; Vizoso Parra,Ángel.
Se evaluó la toxicidad aguda del extracto fluido de Piper auritum H.B.K. así como su actividad genotóxica a través de dos sistemas de ensayo a corto plazo, uno in vitro empleando la cepa D-30 de Aspergillus nidulans y otro in vivo, el ensayo de micronúcleos en médula ósea de ratón. Los resultados permiten concluir que el extracto fluido de P. auritum H.B.K. mostró muy baja toxicidad aguda y resultó genotóxico in vitro pero no in vivo .
Tipo: Journal article
Palavras-chave: Piper auritum H.B.K; Caisimón de anís; Aspergillus nidulans; Ensayo de micronúcleos; Toxicidad aguda; Genotoxicidad.
Ano: 2006
URL: http://scielo.sld.cu/scielo.php?script=sci_arttext&pid=S1028-47962006000300004

Estudio genotóxico in vitro e in vivo en tinturas de Melissa officinalis L. (toronjil) y Mentha piperita L. (toronjil de menta)
Provedor de dados: 98
Autores: Vizoso Parra,Angel; Ramos Ruiz,Alberto; Decalo Michelena,Mercedes; Betancourt Badell,José.
Se emplearon 2 sistema de ensayo de genotoxicidad: uno in vitro, la prueba de segregación mitótica en el hongo diploide Aspergillus nidulans D-30 y otro in vivo, el ensayo de inducción de micronúcleos en médula ósea de ratón. Se evaluó la posible acción de daño genético de las tinturas de Melissa officinalis L. (toronjil) y Mentha piperita L. (toronjil de menta). En el ensayo de segregación mitótica se evaluaron las tinturas de toronjil y toronjil de menta con 4 y 6 concentraciones, respectivamente, en un rango de 0,037 a 0,298 y 0,025 a 0,250 mg de sólidos totales/mL, respectivamente. En el ensayo de inducción de micronúcleos se probaron para el toronjil, dosis de 89,53; 179,06 y 358,11 mg/Kg de peso corporal y en el caso del toronjil de menta, dosis de...
Tipo: Journal article
Palavras-chave: Melissa officinalis L; Mentha piperita L; Aspergillus nidulans; MICRONUCLEOS; GENOTOXICIDAD; SEGREGACION MITOTICA; MEDULA OSEA; RATONES.
Ano: 1997
URL: http://scielo.sld.cu/scielo.php?script=sci_arttext&pid=S1028-47961997000100002

Intra and extracellular nuclease production by Aspergillus niger and Aspergillus nidulans
Provedor de dados: 59
Autores: Ferreira,Adlane V. B.
Intra and extracellular nuclease production by strains of Aspergillus niger and Aspergillus nidulans was estimated using a modified DNAse test agar and cell-free extract assays. Differences in the production of nucleases by A. niger and A. nidulans were observed. These observations suggest that the DNAse test agar can be helpful for a quick screening for some types of nucleases in filamentous fungi. The assays using cell-free extracts can also be useful for initial characterization of other types of nucleases.
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Nucleases; Aspergillus niger; Aspergillus nidulans; Filamentous fungi.
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000400009

Avaliação do potencial antimutagênico do Cogumelo do Sol (Agaricus blazei) no sistema methG1 em Aspergillus (=Emericella) nidulans - DOI: 10.4025/actasciagron.v25i2.2129
Provedor de dados: 1
Autores: Rodrigues, Suzymeire Baroni; UEM; Jabor, Izabel Aparecida Soares; UEM; Marques-Silva, Giuliani Grazyella; UEM; Rocha, Carmem Lucia M. Sartori Cardoso da; UEM.
Muitos cogumelos comestíveis são utilizados com objetivos terapêuticos. Produtores brasileiros já têm investido em cultivo de cogumelos visando ao mercado de fitoterápicos, principalmente pelas suas propriedades anticancerígenas. A capacidade imunomoduladora relacionada aos efeitos antitumorais já tem sido relatada em vários trabalhos, colocando em evidência um grande número de espécies. Entre essas, Agaricus blazei, conhecido como Cogumelo do Sol, tem despertado grande interesse, sendo comercializado no Brasil, para tratamento anticâncer. Esse cogumelo já demonstrou propriedades antitumorais e, mais recentemente, uma publicação apresentou indicação de antimutagenicidade. O objetivo do presente trabalho foi avaliar o potencial antimutagênico do A. blazei...
Palavras-chave: 5.00.00.00-4    Ciências Agrárias antimutagenicidade; Agaricus blazei; Aspergillus nidulans; Sistema metionina 5.00.00.00-4    Ciências Agrárias.
Ano: 2003
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/2129

Cremophor EL stimulates mitotic recombination in uvsH//uvsH diploid strain of Aspergillus nidulans
Provedor de dados: 42
Autores: Busso,Cleverson; Castro-Prado,Marialba A. A.
Cremophor EL is a solubilizer and emulsifier agent used in the pharmaceutical and foodstuff industries. The solvent is the principal constituent of paclitaxel's clinical formulation vehicle. Since mitotic recombination plays a crucial role in multistep carcinogenesis, the study of the recombinagenic potential of chemical compounds is of the utmost importance. In our research genotoxicity of cremophor EL has been studied by using an uvsH//uvsH diploid strain of Aspergillus nidulans. Since it spends a great part of its cell cycle in the G2period, this fungus is a special screening system for the study of mitotic recombination induced by chemical substances. Homozygotization Indexes (HI) for paba and bi markers from heterozygous B211//A837 diploid strain were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus nidulans; Mitotic recombination; Cremophor EL; Homozygotization Index; Antineoplasm agents.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652004000100005

Avaliação do potencial recombinogênico do antibiótico danofloxacina em células diplóides de Apergillus nidulans
Provedor de dados: 45
Autores: Leonardo,A.L.; Castro-Prado,M.A.A.
Estudou-se o potencial recombinogênico da danofloxacina, novo antimicrobiano pertencente ao grupo das 4-fluoroquinolonas e de uso exclusivo em medicina veterinária, no fungo filamentoso Aspergillus nidulans. A linhagem mestra UT196 e o mutante Z1 foram utilizados para formar o diplóide Z1//UT196. Conídios desse diplóide foram inoculados em placas de Petri contendo meio mínimo suplementado com 2,5, 5,0 e 10,0 mig/ml de danofloxacina. As placas foram incubadas por cinco dias a 37 ºC. Segregantes mitóticos foram isolados das colônias tratadas com o antimicrobiano e as análises de seus fenótipos evidenciaram o efeito recombinogênico da danofloxacin na dose de 10,0 mig/ml. Recombinantes para vários intervalos dos cromossomos I e II foram identificados entre os...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus nidulans; Recombinação somática; Danofloxacina.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352001000100021

Vincristine induces somatic segregation, via mitotic crossing-over, in diploid cells of Aspergillus nidulans
Provedor de dados: 48
Autores: CHIUCHETTA,SIMONE JUREMA RUGGERI; CASTRO-PRADO,MARIALBA AVEZUM ALVES DE.
Vincristine is an alkaloid widely used as an antineoplastic agent. In eukaryotic cells the drug causes blockage in the G2 phase of the cell cycle and an increase in the frequency of sister chromatid exchanges. Due to the fact that germinating Aspergillus nidulans cells spend most of their cycle in G2 phase, they provide an excellent system for the study of mitotic crossing-over. Taking into account that mitotic crossing-over occurs during G2 period, the evaluation of recombinagenic and aneugenic potential of vincristine is provided with regard to two diploid strains of A. nidulans: a wild strain (uvsH+//uvsH+) and a defective one in DNA repair (uvsH//uvsH). Drug toxicity and its effect on the asexual cycle of A. nidulans has been evaluated as well....
Tipo: Journal article
Palavras-chave: Aneuploidy; Antineoplastic drug; Aspergillus nidulans; Recombinagenic activity.
Ano: 2002
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000100006

Characterization and mapping of an informational suppressor in Aspergillus nidulans
Provedor de dados: 48
Autores: GRACITE DE MELO FRANZONI,MELISSA; ALVES DE CASTRO-PRADO,MARIALBA AVEZUM.
The present work was undertaken to characterize a suppressor gene present in a mutant strain of A. nidulans obtained with NTG (N-Methyl-N'-Nitro-N-Nitrosoguanidine). Analyses of this mutant have shown that this suppressor, designated suO1, induces phenotypic co-reversion of several auxotrophic mutations and makes the strain sensitive to aminoglycoside antibiotics and lower temperatures. suO1 has shown to be on linkage group VIII. The vegetative growth of the mutant strain is very unstable because the suppressor gene induces the production of prototrophic mitotic sectors. The strains bearing the suO1 gene produce cleistothecia containing a reduced number of viable ascospores during the sexual cycle. The segregation of the genetic markers has also been...
Tipo: Journal article
Palavras-chave: Aspergillus nidulans; Barren cleistothecia; Informational suppressor; Paromomycin.
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000100008

Cytological characterization of an Aspergillus nidulans mutant from a strain with chromosomic duplication
Provedor de dados: 58
Autores: Giancoli,Ágata Cristiane Huppert; Azevedo,João Lúcio de; Kleiner,Aline Aparecida.
A development mutant, named V103, was obtained spontaneously from the A strain of A. nidulans. The A strain contains a duplicated segment of chromosome I that has undergone translocation to chromosome II (I → II). It is mitotically unstable and generates phenotypically deteriorated types, some with enhanced stability. The deteriorated variants of A. nidulans show abnormal development, exhibiting slower colony growth, variations in colony pigmentation and changes in conidiophore structure. The alterations observed in the conidiophore include fewer metulae and phialides, further elongation and ramification of these structures, delayed nuclear migration and the presence of secondary conidiophores.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus nidulans; Conidiogenesis; Nuclear migration; Asexual Cycle; Mitotic Instability.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822010000100036

Antimutagenic action of Lentinula edodes and Agaricus blazei on Aspergillus nidulans conidia
Provedor de dados: 58
Autores: Souza-Paccola,Edneia A.; Bomfeti,Cleide A.; Fávaro,Léia C.L.; Fonseca,Inês C.B.; Paccola-Meirelles,Luzia D.
The antimutagenic effect of the mushrooms Lentinula edodes and Agaricus blazei was studied on conidia of Aspergillus nidulans when exposed to short wave ultraviolet light. Two strains of A. nidulans were used. For the preparation of the extracts, the fresh mushrooms were left in aqueous infusion for 12 hours and heated in a water bath for 15 min at 100ºC, and then the material was filtered. The dehydrated mushrooms were left in aqueous infusion for 12 hours and to filtrated. Both filtrates were used as extracts. A. nidulans conidia were incubated for three hours in water and in mushroom extracts and only after were exposed to UV light (pre-treatment). A. nidulans conidia were suspended in water and in mushroom extracts and immediately submitted to UV light...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antimutagenic; Lentinula edodes; Agaricus blazei; Aspergillus nidulans; Shiitake.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822004000300008

Mechanism of Sterigmatocystin Biosynthesis Regulation by pH in Aspergillus nidulans
Provedor de dados: 58
Autores: Delgado-Virgen,Francisco; Guzman-de-Peña,Doralinda.
External pH constitutes one of the most important environmental factors that control growth, metabolism and differentiation in microorganisms, including fungi. We have analyzed the effect of external pH on sterigmatocystin biosynthesis in Aspergillus nidulans. It was observed in repeated experiments that alkaline pH, in opposition to acid pH, increased sterigmatocystin production and the transcript levels of aflR, the master gene that regulates expression of the sterigmatocystin cluster in A. nidulans. It is known that pH effects in fungi operate mostly through the Pal/Pac signaling pathway, originally described in Aspergillus nidulans. Accordingly, we studied the role of this signaling pathway in ST biosynthesis. It was observed that aflR transcript...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aspergillus nidulans; PH; Sterigmatocystin; PacC.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822009000400027