Antioxidant activity of malt rootlet extracts.

To improve the malt rootlet value, the antioxidant potentialities of this byproduct of the malting industry have been analyzed. Three extracts have been considered from the points of view of dry matter yield, level of antioxidant compounds, and efficiency and cost of the extraction protocols. They respectively contain rootlet oil, free phenolic compounds, and bound phenolic compounds. The rootlet oil contains only a low quantity of tocopherols (respectively, 20.6 and 4.2 microgram of alpha-tocopherol and gamma-tocopherol per gram of dry rootlets), and a weak antioxidant activity, evaluated in a stripped corn oil by following spectrophotometrically the conjugated dienes, has been pointed out. The bound compound extract presents a good antioxidant power mainly due to the presence of trans-ferulic and trans-p-coumaric acids, but the dry matter yield is low (2%). The free compound extract has a good antioxidant power, and the valuable dry matter, mainly composed of proteins (52%), sugars (33%), and reducing compounds (5.5%), has a yield of 12%. The mixing of bound and free compound extracts presents an antagonistic effect on the antioxidant power, but a synergistic effect has been pointed out for the mixing of alpha-tocopherol and free compound extract.

Survival of vascular access during daily and three times a week hemodialysis.

AIM: A major cause of morbidity for hemodialysis patients is vascular access failure and/or occlusion. It is commonly believed that an increased frequency of dialysis sessions, among other factors, might lead to a higher rate of fistula complications. MATERIALS AND METHODS: To evaluate if patients on daily hemodialysis carry a higher risk of vascular access occlusion, we examined the incidence rate of access occlusion and the survival function of native vascular accesses in patients undergoing daily dialysis (DD; n = 24) as compared to patients on standard three times a week hemodialysis (TWD; n = 124). RESULTS: The mean follow-up time was 3.6 years. In the TWD group 42 patients had a first-access closure, whereas only 2 patients out 24 had a similar event in the DD group. The proportion of first-access closure was 33.9% for TWD and 8.3% for DD (p < 0.01). The incidence rate was 9.8 (95% CI: 7.2 -13.2) and 2.2 (95% CI: 0.4 - 7.1) events per 100 patient-years for TWD and DD, respectively. The rate difference was 7.6 (95% CI 3.4 - 11.9) events per 100 patient-years, and the unadjusted risk ratio was 4.5 (95% CI: 1.2 - 16.9; p < 0.01). The mean vascular access survival before closure was 3.3 years in TWD and 3.7 years in DD. Survival curves, obtained considering the first-access closure as the endpoint, showed a significant difference between DD and TWD (log-rank 5.16; p < 0.05). In a Cox-proportional hazard model the relative risk (RR) of vascular-access closure in TWD remained significant (RR = 4.3; 95% CI 1.1 - 18.2) after adjustment for age. CONCLUSION: The results of this observational study, conducted on a limited number of DD patients, suggest that daily dialysis might not have an adverse prognostic significance for access closure.