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71.
Genotoxicity of the coating lacquer on food cans, bisphenol A diglycidyl ether (BADGE), its hydrolysis products and a chlorohydrin of BADGE 总被引:4,自引:0,他引:4
The epoxy resin bisphenol A diglycidyl ether (BADGE), its hydrolysis products and a chlorohydrin of BADGE (BADGE.2HCl), were examined for their genotoxicity in the micronucleus test (MNT) with human peripheral blood lymphocytes in vitro, in presence and in absence of an exogenous metabolizing system S9 rat liver. The treatment was done using different compound concentrations up to cytotoxic doses. The concentrations tested ranged between 12.5 to 62.5microg/ml of BADGE, 12.5 to 62.5microg/ml of first BADGE hydrolysis product (BADGE.H(2)O), 25.0 to 100.0microg/ml of second BADGE hydrolysis product (BADGE.2H(2)O) and 6.25 to 50.0microg/ml of BADGE.2HCl. These compounds are able to induce both cytotoxic and genotoxic effects, as revealed by the increases observed in cytokinesis block proliferation index (CBPI) and in micronuclei (MN) frequencies, respectively. 相似文献
72.
73.
A new Anolis species of the Alpha section from the north region of eastern Cuba (Holguín province) is described. It differs from all Cuban species of Anolis in its green coloration with greenish gray bands on body, legs and tail, in having subtriangular mental scales as well as in other details of color and scutellation. This new species is most closely related to A. isolepis but it can be distinguished from both, A. i. isolepis and A. i. altitudinalis, by its coloration and pattern, the larger body size, the presence of smooth ventral scales (similar in size to the dorsal scales) and by the absence of enlarged postcloacal scales in the male. 相似文献
74.
The gorgonian Leptogorgia sarmentosa contains three new steroids, (20S)-20-hydroxycholestane-3,16-dione (1), (16S, 20S)-16,20-dihydroxycholestan-3-one (2), and (20S)-20-hydroxycholest-1-ene-3,16-dione (3) together with a known related compound (4). Their structures were defined by spectroscopic analysis. The new steroids exhibited significant cytotoxicity against four tumor cell lines (ED50 = 1 microg/ml). 相似文献
75.
76.
Bruno Chauffert Marie-Thérèse Dimanche-Boitrel Carmen Garrido Mikael Ivarsson Monique Martin François Martin Eric Solary 《Cytotechnology》1998,27(1-3):225-235
Kinetic resistance plays a major role in the failure of chemotherapy towards many solid tumors. Kinetic resistance to cytotoxic
drugs can be reproduced in vitro by growing the cells as multicellular spheroids (Multicellular Resistance) or as hyperconfluent
cultures (Confluence-Dependent Resistance). Recent findings on the cell cycle regulation have permitted a better understanding
why cancer cells which arrest in long quiescent phases are poorly sensitive to cell-cycle specific anticancer drugs. Two cyclin-dependent
kinase inhibitors (CDKI) seem particularly involved in the cell cycle arrest at the G1 to S transition checkpoint: the p53-dependent
p21cip1 protein which is activated by DNA damage and the p27kip1 which is a mediator of the contact inhibition signal. Cell quiescence could alter drug-induced apoptosis which is partly
dependent on an active progression in the cell cycle and which is facilitated by overexpression of oncogenes such as c-Myc
or cyclins. Investigations are yet necessary to determine the influence of the cell cycle on the balance between antagonizing
(bcl-2, bcl-XL...) or stimulating (Bax, Bcl-XS, Fas...) factors in chemotherapy-induced apoptosis. Quiescent cells could also be protected from toxic agents by an enhanced
expression of stress proteins, such as HSP27 which is induced by confluence. New strategies are required to circumvent kinetic
resistance of solid tumors: adequate choice of anticancer agents whose activity is not altered by quiescence (radiation, cisplatin),
recruitment from G1 to S/G2 phases by cell pretreatment with alkylating drugs or attenuation of CDKI activity by specific
inhibitors.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
77.
Francisco Espinosa Inmaculada Garrido María Carmen álvarez-Tinaut 《Plant signaling & behavior》2015,10(9)
In vivo redox activities in the apoplast of axenically cultured intact seedling roots (superoxide anion generation, and superoxide dismutase and peroxidase activities) in contact with the compatible arbuscular mycorrhizal fungus (AMF) were clearly attenuated in comparison with those in contact with the pathogenic fungus (PF) or treated with MeJA, even at the early stages of treatment. Contact of roots with the AMF did not enhance the biosynthesis of phenolic compounds (total phenolics, flavonoids, and phenylpropanoid glycosides), while contact with the PF significantly enhanced the biosynthesis of all phenolic fractions. Reactive oxygen and nitrogen species both seemed to be involved in these responses from the first moments of contact, but the fluorescence imaging of roots showed that ROS were mainly accumulated in the apoplast while NO was mainly stored in the cytosol. In conclusion, intact olive seedling roots clearly differentiated between AMF and PF. 相似文献
78.
Marieke H. van der Linden Lidija Seslija Pauline Schneider Emma M. C. Driessen Patricia Garrido Castro Dominique J. P. M. Stumpel Eddy van Roon Jasper de Boer Owen Williams Rob Pieters Ronald W. Stam 《PloS one》2015,10(3)
Introduction
MLL-rearranged acute lymphoblastic leukemia (ALL) in infants (<1 year) is characterized by high relapse rates and a dismal prognosis. To facilitate the discovery of novel therapeutic targets, we here searched for genes directly influenced by the repression of various MLL fusions.Methods
For this, we performed gene expression profiling after siRNA-mediated repression of MLL-AF4, MLL-ENL, and AF4-MLL in MLL-rearranged ALL cell line models. The obtained results were compared with various already established gene signatures including those consisting of known MLL-AF4 target genes, or those associated with primary MLL-rearranged infant ALL samples.Results
Genes that were down-regulated in response to the repression of MLL-AF4 and MLL-ENL appeared characteristically expressed in primary MLL-rearranged infant ALL samples, and often represented known MLL-AF4 targets genes. Genes that were up-regulated in response to the repression of MLL-AF4 and MLL-ENL often represented genes typically silenced by promoter hypermethylation in MLL-rearranged infant ALL. Genes that were affected in response to the repression of AF4-MLL showed significant enrichment in gene expression profiles associated with AF4-MLL expressing t(4;11)+ infant ALL patient samples.Conclusion
We conclude that the here identified genes readily responsive to the loss of MLL fusion expression potentially represent attractive therapeutic targets and may provide additional insights in MLL-rearranged acute leukemias. 相似文献79.
Leire Aguinagalde Bruno Corsini Arnau Domenech Mirian Domenech Jordi Cámara Carmen Ardanuy Ernesto García Josefina Li?ares Asunción Fenoll Jose Yuste 《PloS one》2015,10(9)
Capsular switching allows pre-existing clones of Streptococcus pneumoniae expressing vaccine serotypes to escape the vaccine-induced immunity by acquisition of capsular genes from pneumococci of a non-vaccine serotype. Here, we have analysed the clonal composition of 492 clinical isolates of serotype 11A causing invasive disease in Spain (2000–2012), and their ability to evade the host immune response. Antibiograms, serotyping and molecular typing were performed. The restriction profiles of pbp2x, pbp1a and pbp2b genes were also analysed. Interaction with the complement components C1q, C3b, C4BP, and factor H was explored whereas opsonophagocytosis assays were performed using a human cell line differentiated to neutrophils. Biofilm formation and the polymorphisms of the major autolysin LytA were evaluated. The main genotypes of the 11A pneumococci were: ST62 (447 isolates, 90.6%), followed by ST6521 (35 isolates, 7.3%) and ST838 (10 isolates, 2.1%). Beta lactam resistant serotype 11A variants of genotypes ST838 and ST6521 closely related to the Spain9V-ST156 clone were first detected in 2005. A different pattern of evasion of complement immunity and phagocytosis was observed between genotypes. The emergence of one vaccine escape variant of Spain9V-ST156 (ST652111A), showing a high potential to avoid the host immune response, was observed. In addition, isolates of ST652111A showed higher ability to produce biofilms than ST83811A or ST6211A, which may have contributed to the emergence of this PEN-resistant ST652111A genotype in the last few years. The emergence of penicillin-resistant 11A invasive variants of the highly successful ST156 clonal complex merits close monitoring. 相似文献
80.
Marina Garcia Garrido Regine L. Mühlfriedel Susanne C. Beck Christine Wallrapp Mathias W. Seeliger 《PloS one》2015,10(6)