scholarly journals Methylxanthines (caffeine, pentoxifylline and theophylline) decrease the mutagenic effect of daunomycin, doxorubicin and mitoxantrone.

2005 ◽  
Vol 52 (4) ◽  
pp. 923-926 ◽  
Author(s):  
Jacek Piosik ◽  
Anna Gwizdek-Wiśniewska ◽  
Katarzyna Ulanowska ◽  
Jakub Ochociński ◽  
Agata Czyz ◽  
...  
Keyword(s):  
Aromatic Compounds ◽  
Mutagenic Effect ◽  
Spectrophotometric Titration ◽  
Stacking Interactions ◽  
Electron Systems ◽  
Cytotoxic Effects ◽  
Aromatic Molecules ◽  
Mixed Aggregates ◽  
Polycyclic Aromatic

Previously performed experiments showed that methylxanthines, especially caffeine, may protect cells against cytostatic or cytotoxic effects of several aromatic compounds. One of the proposed mechanisms of this protection is based on stacking interactions between pi electron systems of polycyclic aromatic molecules. In this work, we demonstrate that caffeine and other methylxanthines--pentoxifylline and theophylline--significantly decrease mutagenicity of the anticancer aromatic drugs daunomycin, doxorubicin and mitoxantrone. The spectrophotometric titration of these aromatic compounds by methylxanthines indicated formation of mixed aggregates. The concentrations of free active forms of the drugs decreased when the concentrations of methylxanthines increased in the mixture. Therefore, likely methylxanthines may play a role of scavengers of the free active forms of daunomycin, doxorubicin and mitoxantrone.

scholarly journals Aromatic adsorption on metals via first-principles density functional theory

2009 ◽  
Vol 465 (2110) ◽  
pp. 2949-2976 ◽  
Author(s):  
S. J. Jenkins
Keyword(s):  
First Principles ◽  
Density Functional ◽  
Functional Theory ◽  
Aromatic Molecules ◽  
Polycyclic Aromatic ◽  
Non Covalent Interactions ◽  
Covalent Interactions ◽  
Case Basis ◽  
Electronic And Steric Effects

We review first-principles calculations relevant to the adsorption of aromatic molecules on metal surfaces. Benzene has been intensively studied on a variety of substrates, providing an opportunity to comment upon trends from one metal to another. Meanwhile, calculations elucidating the adsorption of polycyclic aromatic molecules are more sparse, but nevertheless yield important insights into the role of non-covalent interactions. Heterocyclic and substituted aromatic compounds introduce the complicating possibility of electronic and steric effects, whose relative importance can thus far only be gauged on a case-by-case basis. Finally, the coadsorption and/or reaction of aromatic molecules is discussed, highlighting an area where the predictive power of theory is likely to prove decisive in the future.

scholarly journals Paenarthrobacter sp. GOM3 Is a Novel Marine Species With Monoaromatic Degradation Relevance

2021 ◽  
Vol 12 ◽  
Author(s):  
Jaime Rosas-Díaz ◽  
Alejandra Escobar-Zepeda ◽  
Libertad Adaya ◽  
Jorge Rojas-Vargas ◽  
Diego Humberto Cuervo-Amaya ◽  
...  
Keyword(s):  
Aromatic Compounds ◽  
Genomic Analysis ◽  
Marine Species ◽  
Degradation Pathway ◽  
Pathogenic Potential ◽  
Gene Copies ◽  
Intermediate Metabolites ◽  
Polycyclic Aromatic ◽  
Species Specific

Paenarthrobacter sp. GOM3, which is a strain that represents a new species-specific context within the genus Paenarthrobacter, is clearly a branched member independent of any group described thus far. This strain was recovered from marine sediments in the Gulf of Mexico, and despite being isolated from a consortium capable of growing with phenanthrene as a sole carbon source, this strain could not grow successfully in the presence of this substrate alone. We hypothesized that the GOM3 strain could participate in the assimilation of intermediate metabolites for the degradation of aromatic compounds. To date, there are no experimental reports of Paenarthrobacter species that degrade polycyclic aromatic hydrocarbons (PAHs) or their intermediate metabolites. In this work, we report genomic and experimental evidence of metabolic benzoate, gentisate, and protocatechuate degradation by Paenarthrobacter sp. GOM3. Gentisate was the preferred substrate with the highest volumetric consumption rate, and genomic analysis revealed that this strain possesses multiple gene copies for the specific transport of gentisate. Furthermore, upon analyzing the GOM3 genome, we found five different dioxygenases involved in the activation of aromatic compounds, suggesting its potential for complete remediation of PAH-contaminated sites in combination with strains capable of assimilating the upper PAH degradation pathway. Additionally, this strain was characterized experimentally for its pathogenic potential and in silico for its antimicrobial resistance. An overview of the potential ecological role of this strain in the context of other members of this taxonomic clade is also reported.

scholarly journals Role of terminal groups in aromatic molecules on the growth of Al2O3-based hybrid materials

2021 ◽  
Author(s):  
Arbresha Muriqi ◽  
Maarit Karppinen ◽  
Michael Nolan
Keyword(s):  
Molecular Mechanism ◽  
Hybrid Materials ◽  
First Principles ◽  
Aromatic Compounds ◽  
Aromatic Molecules

First principles investigation of the molecular mechanism of Al2O3-based hybrid materials grown with homo- or hetero-bifunctional aromatic compounds with hydroxy (OH) and/or amino (NH2) terminal groups.

The Role of Spring Flood and Landscape Type in the Terrestrial Export of Polycyclic Aromatic Compounds to Streamwater

2018 ◽  
Vol 52 (11) ◽  
pp. 6217-6225 ◽  
Author(s):  
Minh A. Nguyen ◽  
Lutz Ahrens ◽  
Jakob Gustavsson ◽  
Sarah Josefsson ◽  
Hjalmar Laudon ◽  
...  
Keyword(s):  
Aromatic Compounds ◽  
Polycyclic Aromatic Compounds ◽  
Spring Flood ◽  
Landscape Type ◽  
Polycyclic Aromatic

The Correlation Pattern of Fly Ash Components: Chromium as a Potential Catalyst in the Thermal Formation of Chlorinated Aromatic Compounds

2004 ◽  
Vol 1 (1) ◽  
pp. 18 ◽  
Author(s):  
Tomas Öberg ◽  
Tomas Öhrström ◽  
Jan Bergström
Keyword(s):  
Fly Ash ◽  
Organic Pollutants ◽  
Aromatic Compounds ◽  
Catalytic Effect ◽  
Chlorinated Phenols ◽  
Correlation Pattern ◽  
Aromatic Molecules ◽  
Chemical Agents ◽  
Chlorinated Aromatic Compounds

Environmental Context.Harmful chlorinated aromatic molecules are often formed and released into the environment during incineration of municipal waste and other waste fuels. This is a problem that has been known since the 1970s, and while efforts are being made to reduce these emissions, these persistent organic pollutants are still subsequently released into the environment, with residues and emissions to the atmosphere. In an attempt to uncover the chemical agents responsible for the formation of these pollutants, this study reveals that chromium, a commonly encountered metal, could be an important factor. Abstract.Chlorinated aromatic compounds are unintentionally released from combustion sources into the environment. This thermal formation is catalyzed by fly ash components and much interest has been focussed on the role of copper. This study report results from a series of 16 full-scale trials with different fuel compositions. The correlation pattern of fly ash components seem to suggest that the catalytic effect may be due also to other metal oxychlorination catalysts. Chromium shows particularly strong and statistically significant correlations with many of the chlorinated phenols, benzenes, dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs).

Transmission Electron Microscopy of Evaporated Perylene Thin Films

1990 ◽  
Vol 48 (2) ◽  
pp. 336-337
Author(s):  
C. Ewins ◽  
J.R. Fryer
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Molecular Electronics ◽  
High Vacuum ◽  
Amorphous Layer ◽  
Electric Heater ◽  
Transmission Electron ◽  
Polycyclic Aromatic

The preparation of thin films of organic molecules is currently receiving much attention because of the need to produce good quality thin films for molecular electronics. We have produced thin films of the polycyclic aromatic, perylene C10H12 by evaporation under high vacuum onto a potassium chloride (KCl) substrate. The role of substrate temperature in determining the morphology and crystallography of the films was then investigated by transmission electron microscopy (TEM).The substrate studied was the (001) face of a freshly cleaved crystal of KCl. The temperature of the KCl was controlled by an electric heater or a cold finger. The KCl was heated to 200°C under a vacuum of 10-6 torr and allowed to cool to the desired temperature. The perylene was then evaporated over a period of one minute from a molybdenum boat at a distance of 10cm from the KCl. The perylene thin film was then backed with an amorphous layer of carbon and floated onto copper microscope grids.

Sign in / Sign up

Export Citation Format

Share Document