Serum urate level and cancer.

Histograms of the serum uric acid level of cancer patients (n = 501) and healthy controls (n = 15150) are compared. The statistical evaluation of the data yields significantly lower uric acid levels for cancer patients than for healthy persons (P less than 0.0001 for males, P less than 0.001 for females). These results support the theory that reactive species of oxygen (singlet oxygen and oxygen radicals) play an important role during carcinogenesis.

Intracellular oxidative cleavage of DNA in Escherichia coli by the copper-1,10-phenanthroline complex.

Plasmid and chromosomal DNA of E. coli during exponential growth are cleaved after treatment with copper(II)-1, 10-phenanthroline complex (1:2) without providing any exogenous reductant. About 1500 copper molecules per cell are present as estimated by atomic absorption analysis. Within the cell the endogenous reducing substances may have participated in the sequential oxidative reactions, which lead to the damage of DNA. A portion of the resultant DNA fragments originates from plasmid DNA as demonstrated by hybridization tests.

[Electrophoretic studies on the effect of different types of radiation (60Co, electrons, x-ray, photons, UV) on low-molecular ribonucleic acids]. / Elektrophoretische Untersuchungen des Einflusses von verschiedenen Strahlungsarten (60Co, Elektronen, Röntgen, Photonen und UV) auf niedermolekulare Ribonukleinsäuren.

Electron irradiation (45 MeV) with the chosen doses modifies the molecule composition of isolated dry yeast RNA. High-energy irradiation will crack the RNA which then forms new chains of macromolecular nucleic acids. Other radiation types (60Co, photons, X-rays) do not modify dry RNA, but when irradiated in aqueous solution, these macromolecular bands will be built, too. After UV irradiation with 254 nm delivered over 24 hours these macromolecular bands disappear completely in the electrophoretic diagram. This wavelength corresponds to the absorption maximum of purines, thus stimulating them and reducing their stability.

[Fundamental model assays on chemical damages to ribonucleic acids caused by oxygen radicals in aqueous solution]. / Grundlegende Modellversuche über chemische Schädigungen von Ribonukleinsäuren durch Sauerstoffradikale in wässriger Lösung.

A partial decomposition of RNA molecules in Saccharomyces cerevisiae is caused by photochemically produced superoxide anion radical (O2-.). Hydroxyl radicals (OH.) lead to complete destruction of RNA. Such radicals as originating from peroxidase-hydrogen peroxide reaction cause a partial decomposition of RNA molecules. All RNA species are damaged to the same extent by radicals. Damages due to oxygen radicals can be prevented or reduced by strong radical captors (dimethyl sulfoxide, 1,4-diazabicyclo-(2,2,2)-octane or superoxide dismutase). All these reactions proceed in aqueous solution. Correlations with the use of radicals in radiotherapy are discussed.

[Changes in serum protein patterns in cancer patients during radiotherapy]. / Veränderungen im Serumproteinmuster von Karzinompatientinnen bei Strahlentherapie.

The serum protein spectrum of a PAGE separation shows characteristic and permanent modifications in patients of premenopausal age submitted to a curative or postoperative irradiation by high dose rate afterloading method or percutaneous telecobalt therapy for carcinoma of the cervix. In older patients, the serum protein spectrum remains nearly unchanged during and after radiotherapy.