Studies of the potential genotoxic effects of furoxans: the case of CAS 1609 and of the water-soluble analogue of CHF 2363.

CAS 1609 (compound 1) and CHF 2363 (compound 2) are two furoxan derivatives able to release nitric oxide (NO) under physiological conditions, and display typical NO-dependent vasodilator activity. The potential genotoxic effects of compound 1 and of the water-soluble analogue of CHF 2363 (compound 2a) were investigated. The results show that the two compounds induce genotoxic effects only at concentrations that significantly reduce cell viability. However, in the case of compound 1 this range of concentrations is one order of magnitude higher than the one leading to the beneficial effects, while in the case of compound 2a these ranges partially overlap. In both cases the release of NO plays a key role in the induction of the cytotoxic and genotoxic effects, since the non-NO-donating furazan analogues display a different toxicological profile, and since the effects were reduced in the presence of oxyhaemoglobin, a well-known NO-scavenger.

A new class of ibuprofen derivatives with reduced gastrotoxicity.

A new series of nonsteroidal antiinflammatory drugs (NSAIDs) obtained by linking ibuprofen to selected furoxan moieties and to related furazans were synthesized and tested for their antiinflammatory, antiaggregatory, and ulcerogenic properties. All the derivatives are endowed with antiinflammatory activity comparable to that of ibuprofen, but, unlike this drug, they display reduced acute gastrotoxicity. The masking of the ibuprofen-free carboxylic group seems to be principally at the basis of this reduced topical irritant action. The two furoxan derivatives 8 and 9 also trigger potent antiaggregatory effects, principally as a consequence of their NO-donor ability.

Effects of homeopathic arsenic on tobacco plant resistance to tobacco mosaic virus. Theoretical suggestions about system variability, based on a large experimental data set.

CONTEXT: This research aimed at verifying the efficacy of homeopathic treatments by plant-based bioassays, which may be suitable for basic research, because they lack placebo effects and provide large datasets for statistical analyses. OBJECTIVE: To evaluate the effects of homeopathic treatments of arsenic trioxide (As2O3) on tobacco plants subjected to tobacco mosaic virus (TMV) inoculation as biotic stress. DESIGN: Blind, randomized experiment using tobacco leaf disks. MATERIALS AND METHODS: Tobacco plants (Nicotiana tabacum L. cultivar Samsun) carrying the TMV resistance gene N. TMV inoculated leaf disks were floated for 3 days in the following: Distilled water (control). H2O 5 and 45 decimal and centesimal potencies. As2O3 5 and 45 decimal and centesimal potencies. The main outcome measures is the number of hypersensitive lesions observed in a leaf disk. RESULTS: Homeopathic treatments of arsenic induce two effects on the plant: (i) increased resistance to TMV; (ii) decrease variability between experiments (system variability). CONCLUSIONS: In this experimental model two actions of homeopathic treatment were detected: decrease in system variability and enhancement of the natural tendency of the system towards an 'equilibrium point'.