Characterization of fluorescent products from reaction of methyl linoleate hydroperoxides with adenine in the presence of Fe2+ and ascorbic acid

The structures of fluorescent products formed in the reaction of methyl linoleate hydroperoxides with adenine, FeSO4 and ascorbic acid were investigated to elucidate the mechanism of interaction. The fluorescent products consisted of at least four major components (I-IV), which could be separated by thin-layer chromatography and high-performance liquid chromatography. Both 2-octenal and 2,4-decadienal, degradation products of methyl linoleate hydroperoxides, reacted with adenine to produce a fluorescent product similar to one of the major compounds (II) formed in the reaction of methyl linoleate hydroperoxides. Spectroscopic data suggest that I and III are the same type of compounds, which have closed ring structures with alpha, beta-unsaturated carbonyl groups between the amino group at the 6-position and the nitrogen at the 1-position of adenine. Component II has a closed ring structure at the same site as I and III, and the presence of an ether linkage was suggested. On the basis of these structures, the involvement of 3-nonenal, methyl 12-oxo-9-dodecenoate and 2-octenal was suggested in the interaction of the methyl linoleate hydroperoxides decomposition products and adenine or DNA in the presence of FeSO4 and ascorbic acid.     

A new strain congenic for the Mtv-7/Mls-1 locus of mouse chromosome 1

Correspondence to: B. A. Taylor.     

Effects of a carotene-deficient diet on measures of oxidative susceptibility and superoxide dismutase activity in adult women

The effect of consuming a low carotene diet (≈60 μg carotene/day) on oxidative susceptibility and superoxide dismutase (SOD) activity in women living in a metabolic research unit was evaluated. The diet had sufficient vitamins A, E, and C. The women ate the diet supplemented with 1500 μg/day β-carotene for 4 days (baseline), then the unsupplemented diet for 68 days (depletion), followed by the diet supplemented with > 15,000 μg/day carotene for 28 days (repletion). Production of hexanal, pentanal, and pentane by copper-oxidased plasma low density lipoproteins from carotene-depleted women was greater than their production of these compounds when repleted with carotene. Erythrocyte SOD activity was depressed in carotene-depleted women; it recovered with repletion. Thiobarbituric acid reactive substances in plasma of carotene-depleted women were elevated and diminished with repletion. Dietary carotene seems to be needed, not only as a precursor of vitamin A, but also to inhibit oxidative damage and decrease oxidation susceptibility.     

Alternatives to hospital care: what are they and who should decide?

OBJECTIVE--To examine potential for alternatives to care in hospitals for acute admissions, and to compare the decisions about these alternatives made by clinicians with different backgrounds. DESIGN--Standardised tool was used to identify patients who could potentially be treated in an alternative form of care. Information about such patients was assessed by three panels of clinicians: general practitioners without experience of general practitioner beds, general practitioners with experience of general practitioner beds, and consultants. SETTING--One hospital for acute admissions in a rural area of the South and West region of England. SUBJECTS--Of 620 patients admitted to specialties of general medicine and care of the elderly, details of 112 were assessed by panels. MAIN OUTCOME MEASURES--Proportion of hospitalised patients who could have received alternative care and identification of most appropriate alternative form of care. RESULTS--Both general practitioner panels estimated that between 51 and 89 of the hospitalised patients could have received alternative care (equivalent to 8-14% of all admissions). Consultants estimated that between 25 and 55 patients could have had alternative care (5.5-9% of all admissions). General practitioner bed and urgent outpatient appointment were the main alternatives chosen by all three panels. CONCLUSION--About 10% of admissions to general hospital might be suitable for alternative forms of care. Doctors with different backgrounds made similar overall assessments of most appropriate forms of care.