In soil, fertilizers containing inorganic nitrogen and wastes containing organic nitrogen are first decomposed to give ammonia, which is then oxidized to nitrite and nitrate. The nitrate is taken up by plants during their growth and used in the synthesis of organic nitrogenous compounds. Surplus nitrate readily moves with groundwater (2, 3). Under aerobic conditions, it percolates in large quantities into the aquifer because of the small extent to which degradation or denitrification occurs. Under anaerobic conditions, nitrate may be denitrified or degraded almost completely to nitrogen. The presence of high or low water tables, the amount of rainwater, the presence of other organic material, and other physicochemical properties are also important in determining the fate of nitrate in soil ( 4). In surface water, nitrification and denitrification may also occur, depending on the temperature and pH. The uptake of nitrate by plants, however, is responsible for most of the nitrate reduction in surface water. Nitrogen compounds are formed in the air by lightning or discharged into it from industrial processes, motor vehicles, and intensive agriculture. Nitrate is present in air primarily as nitric acid and inorganic aerosols, as well as nitrate radicals and organic gases or aerosols. These are removed by wet and dry deposition.

WHO guidelines for drinking-water quality.

The glutathione S-transferases (GST) represent a major group of detoxification enzymes. All eukaryotic species possess multiple cytosolic and membrane-bound GST isoenzymes, each of which displays distinct catalytic as well as noncatalytic binding properties: the cytosolic enzymes are encoded by at least five distantly related gene families (designated class alpha, mu, pi, sigma, and theta GST), whereas the membrane-bound enzymes, microsomal GST and leukotriene C, synthetase, are encoded by single genes and both have arisen separately from the soluble GST. Evidence suggests that the level of expression of GST is a crucial factor in determining the sensitivity of cells to a broad spectrum of toxic chemicals. In this article the biochemical functions of GST are described to show how individual isoenzymes contribute to resistance to carcinogens, antitumor drugs, environmental pollutants, and products of oxidative stress.A description of the mechanisms of transcriptional and posttranscriptional regulat...

The glutathione S-transferase supergene family: regulation of GST and the contribution of the isoenzymes to cancer chemoprotection and drug resistance.

The immunobiology of cancer immunosurveillance and immunoediting

The biochemistry and medical significance of the flavonoids.

The emergence of tissue engineering raises new possibilities for the study of complex physiological and pathophysiological processes in vitro. Many tools are now available to create 3D tissue models in vitro, but the blueprints for what to make have been slower to arrive. We discuss here some of the 'design principles' for recreating the interwoven set of biochemical and mechanical cues in the cellular microenvironment, and the methods for implementing them. We emphasize applications that involve epithelial tissues for which 3D models could explain mechanisms of disease or aid in drug development.

Capturing complex 3D tissue physiology in vitro.

https://aasldpubs.onlinelibrary.wiley.com/doi/pdf/10.1002/hep.1840190326

Deficiency of bile acid transport and synthesis in oval cells from carcinogen-fed rats.

Direct Analysis of Phase I Metabolites, Phenol Sulfates, Glucuronides and Glutathione Conjugates of Benzo[a]pyrene in Freshly Isolated, Hypothermically Stored and Cryopreserved Hepatocytes

Improved syntheses of (.+-.)-trans-9,10-dihydroxy-9,10-dihydrobenzo(a)pyrene and of (.+-.)-trans-1,2-dihydroxy-1,2-dihydrodibenz(a,h)anthracene

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1016/0014-5793%2887%2980911-0

Franz Oesch

Papers

Deficiency of bile acid transport and synthesis in oval cells from carcinogen-fed rats.

Direct Analysis of Phase I Metabolites, Phenol Sulfates, Glucuronides and Glutathione Conjugates of Benzo[a]pyrene in Freshly Isolated, Hypothermically Stored and Cryopreserved Hepatocytes

Improved syntheses of (.+-.)-trans-9,10-dihydroxy-9,10-dihydrobenzo(a)pyrene and of (.+-.)-trans-1,2-dihydroxy-1,2-dihydrodibenz(a,h)anthracene

Effect of unbalanced diets on incorporation of δ-aminolevulinic acid into cytochrome P-450

Activities of drug-metabolizing enzymes in cultured mammalian cells used for the detection of mutagens