Relevance of the deletion polymorphisms of the glutathione S-transferases GSTT1 and GSTM1 in pharmacology and toxicology

Although cytosolic glutathione S-transferase (GST) enzymes occupy a key position in biological detoxification processes, two of the most relevant human isoenzymes, GSTT1-1 and GSTM1-1, are genetically deleted (non-functional alleles GSTT1*0 and GSTM1*0) in a high percentage of the human population, with major ethnic differences. The structures of the GSTT and GSTM gene areas explain the underlying genetic processes. GSTT1-1 is highly conserved during evolution and plays a major role in phase-II biotransformation of a number of drugs and industrial chemicals, e.g. cytostatic drugs, hydrocarbons and halogenated hydrocarbons. GSTM1-1 is particularly relevant in the deactivation of carcinogenic intermediates of polycyclic aromatic hydrocarbons. Several lines of evidence suggest that hGSTT1-1 and/or hGSTM1-1 play a role in the deactivation of reactive oxygen species that are likely to be involved in cellular processes of inflammation, ageing and degenerative diseases. There is cumulating evidence that combinations of the GSTM1*0 state with other genetic traits affecting the metabolism of carcinogens (CYP1A1, GSTP1) may predispose the aero-digestive tract and lung, especially in smokers, to a higher risk of cancer. The GSTM1*0 status appears also associated with a modest increase in the risk of bladder cancer, consistent with a GSTM1 interaction with carcinogenic tobacco smoke constituents. Both human GST deletions, although largely counterbalanced by overlapping substrate affinities within the GST superfamily, have consequences when the organism comes into contact with distinct man-made chemicals. This appears relevant in industrial toxicology and in drug metabolism.

Mauve: How one man invented the colour that changed the world

In an essay, "The Books of Last Things", Delia Falconer discusses the emergence of a new genre in publishing - microhistories. She cites a number of recent titles in non-fiction and fiction - Longitude, Cod, Tulips, Pushkin's Button, Nathaniel's Nutmeg, Zarafa, The Surgeon of Crowthorne, The Potato, The Perfect Storm. Delia Falconer observes of this tradition: "One has the sense, reading these books, of a surprising weight, of pleasant shock. In part, it is because we are looking at things which are generally present around us, but modestly out of sight and mind - historical nitty gritty like cod, potatoes, longitudinal clocks - which the authors have thrust suddenly, like a Biblical visitation of frogs or locusts, in our face. Things like spice and buttons and clocks are generally seen to enable history on the large scale, but are not often viewed as its worthy subjects. And by the same grand logic of history, more unusual phenomena like cabinets of curiosities or glass-making or farm lore or sailors' knots are simply odd blips on its radar screen, interesting footnotes. These new books, microhistories, reverse the usual order of history, which argues from the general to the particular, in order to prove its inevitable progress. They start from the footnotes. But by reversing the process, and walking through the back door of history, you don't necessarily end up at the front of the same house." Delia Falconer speculates about the reasons for the popularity of microhistories. She concludes: "I would like to think that reading them is not simply an exercise in nostalgia, but a challenge to the present". In Mauve, Simon Garfield provides a new way of thinking and writing about the history of intellectual property. Instead of providing a grand historical narrative of intellectual property, he tells the story of a particular invention, and its exploitation. Simon Garfield relates how English chemist William Perkin accidentally discovered a way to mass-produce colour mauve in a factory. Working on a treatment for malaria in his London home laboratory, Perkin failed to produce artificial quinine. Instead he created a dark oily sludge that turned silk a beautiful light purple. The colour was unique and became the most desirable shade in the fashion houses of Paris and London. ... The book Mauve will have a number of contemporary resonances for intellectual property lawyers and academics. Simon Garfield emphasizes the difficulties inherent in commercialising an invention and managing intellectual property. He investigates the uneasy collaboration between industry and science. Simon Garfield suggests that complaints about the efficacy of patent offices are perennial. He also highlights the problems faced by courts and law-makers in accommodating new technologies within the logic of patent law. In his elegant microhistory of the colour mauve, Simon Garfield confirms the conclusion of Brad Sherman and Lionel Bently that many aspects of modern intellectual property law can only be understood through an understanding of the past: "The image of intellectual property law that developed during the 19th century and the narrative of identity which this engendered played and continue to play an important role in the way we think about and understand intellectual property law".

A novel fluorescent probe involving a graphene quantum dot-enzyme hybrid system for the analysis of hydroquinone in the presence of toxic resorcinol and catechol

An efficient method for the analysis of hydroquinone at trace levels in water samples has been developed in the form of a fluorescent probe based on graphene quantum dots (GQDs). The analytical variable, fluorescence quenching, was generated from the formation of benzoquinone intermediates, which formed during the catalytic oxidation of hydroquinone by horseradish peroxidase (HRP). In general, the reaction mechanism involved hydroquinone, as an electron acceptor, which affected the surface state of GQDs via an electron transfer effect. The water-soluble GQDs were directly prepared by the pyrolysis of citric acid and with the use of the mentioned hybrid enzyme system, the detection limit for hydroquinone was as low as 8.4 × 10−8 M. Furthermore, this analysis was almost unaffected by other phenol and quinine compounds, such as phenol, resorcinol and other quinines, and therefore, the developed GQD method produced satisfactory results for the analysis of hydroquinone in several different lake water samples.