The activity of yeast invertase as a function of oxidation-reduction potential has been investigated using a large number of oxidants and reductants. The activity is constant over the range of E(h) from -270 to +600 mv., but above E(h) = +600 mv. there is a sharp decrease in activity reaching 0 at E(h) = +1,000 mv. The inhibiting action of strong oxidants is upon the enzyme rather than on the s...

There is now compelling evidence that proteinases and oxidative stress play pathogenetic roles in the following pathologies in chronic obstructive pulmonary disease: airspace enlargement; chronic inflammation in the airways, lung interstitium, and alveolar space; and mucus hypersecretion in the large airways. Proteinases and oxidants may also contribute to remodeling processes in the small airw...

Objective. We quantitatively assessed the influence of oxidants on antigen-antibody-binding activity. Methods. We used several immunological detection methods, including precipitation reactions, agglutination reactions, and enzyme immunoassays, to determine antibody activity. The oxidation-reduction potential was measured in order to determine total serum antioxidant capacity. Results. Certain ...

Many decades of research have produced a significant amount of data showing increased oxidative stress in asthma and indicating a potential role for oxidants in the pathogenesis of the disease, particularly during exacerbations. Putatively relevant pro-oxidative mechanisms have also been identified. Currently available asthma drugs are generally effective for the treatment of the disease, but t...

Body has defense mechanisms against oxidants in the form of both enzymatic and non enzymatic antioxidants. Oxidants have both physiological and pathological role in female reproduction. Oxidative stress causes damage to the ovaries, oogonia and ovulation as well as in implantation procedures. A study was undertaken to evaluate the polycystic ovary syndrome (PCOS) induced stress in ovarian and u...

Mitogen-induced transformation and the production of reactive oxidants by mononuclear leucocytes (MNLs) from patients with chronic dermatological disorders were investigated in vitro before and during the administration of the antimycobacterial/immunosuppressive agent clofazimine (200 mg 3 times weekly). Seven patients, 4 with lichen planus and 3 with cutaneous lupus erythematosus, were include...

The p53 tumour-suppressor protein is a transcription factor that activates the expression of genes involved in cell cycle arrest, apoptosis and DNA repair. The p53 protein is vulnerable to oxidation at cysteine thiol groups. The metal-chelating dithiocarbamates, pyrrolidine dithiocarbamate (PDTC), diethyldithiocarbamate, ethylene(bis)dithiocarbamate and H(2)O(2) were tested for their oxidative ...