Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:6.3.5.5 (CPS)
 1,262 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An improved protocol was developed to detect light-induced clastogenic photoproducts in Chinese hamster ovary (CHO) cells. Dishes (60 mm) containing cells and the test material or vehicle control in 3 mL of phosphate-buffered saline were exposed to light using a SUNTEST CPS solar simulation unit. Importantly, cells were exposed at about 25 cm from the light source, thereby allowing a short exposure time of 2 min. With this exposure the assay was conducted with lids removed during the UV exposure with minimal risk of contamination. After preliminary experiments an exposure of 165.6 mJ/cm(2) UVA: 17.0 mJ/cm(2) UVB was selected for treatments with the different phototoxins. Under these exposure conditions about 10-15% aberrant cells were induced in vehicle control cultures with no or minimal cytotoxicity. The well-known photoclastogens 8-methoxypsoralen (8-MOP) and chlorpromazine (CLZ) were tested. In agreement with published data, 8-MOP and CLZ were clastogenic (lowest observed effect level, LOEL, was 0.0159 microg/mL and 1.03 microg/mL, respectively). In the absence of UV, 8-MOP was clastogenic at a much higher concentration (LOEL 251 microg/mL without UV vs. 0.0159 microg/mL with UV) while CLZ was negative up to a toxic concentration of 35 microg/mL. 7,12-Dimethylbenz[a]anthracene (DMBA), which is photomutagenic in bacteria, was clastogenic at > or =0.005 microg/mL with UV light (without S9) and at > or =2.53 microg/mL with S9 (without UV light). These results demonstrate the utility of the protocol for the detection of photoclastogenicity and expand the characterization of DMBA's photogenotoxic activity.
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PMID:Photoclastogenicity-an improved protocol, its validation, and investigation of the photogenotoxicity of DMBA. 1221 Oct 75

Gold Nanomaterials (GNMs) interact with fluorophores via electromagnetic coupling under excitation. In this particular work we carried out (to the best of our knowledge for the first time) a comprehensive study of systematic quenching of a blue emitter 2-Anthracene Sulfonate (2-AS) in the presence of gold nanoparticles of different size and shape. We synthesized gold nanomaterials of four different dimensions [nanoparticle (0D), nanorod (1D), nanotriangle (2D) and nanobipyramids (3D)] and realized the underlying effect on the emitting dipole in terms of steady and time resolved fluorescence. Nanometal Surface Energy Transfer (NSET) has already been proved to be the best long range spectroscopic ruler so far. Many attempts have been made to understand the interaction between a fluorescent molecule and gold nanomaterials. But not a single model can interpret alone the interaction phenomena. We have opted three different models to compare the experimental and theoretical data. Due to the presence of size dependent absorptivity and dielectric function, modified CPS-Kuhn model was proved to be the worthiest to comprehend variance of behavior of an emitting dipole in close proximity to nanometal surface by coupling with the image dipole of gold nanomaterials.
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PMID:Understanding the effect of size and shape of gold nanomaterials on nanometal surface energy transfer. 2805 44