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Introduction A recent study suggested that orally dosed ferric citrate hydrate (FC) corrects renal anemia in patients on hemodialysis (HD), suggesting biological differences in effects of iron supplementation using different routes of administration. To address this issue, the present study compared oral FC with i.v. saccharated ferric oxide (FO) in stable HD patients. Methods Participants comprised 6 patients administered 3 consecutive protocols in the first HD session of the week in a fasting state: nothing given, as control (C); oral load of FC (480 mg iron), and 5 minutes of i.v. FO (40 mg iron). Iron dynamics in the body and biological impact on redox-inflammation status during the study (6 hours) were examined. Results Significant increases in serum iron and transferrin saturation were seen with both FC and FO. Regarding total iron-binding capacity as the sum of serum iron and unsaturated iron-binding capacity, no changes were found in FC, whereas significant increases were seen in FO (appearance of non–transferrin-binding iron [NTBI]), despite the lower serum iron levels in FO. Compared with C, increases were seen in serum myeloperoxidase (oxidative marker) with accompanying significant decreases in thioredoxin (antioxidant) in FO, whereas no changes were found in FC. Conclusion Oral FC differs from i.v. FO in areas such as less NTBI generation and less induction of oxidative stress. The result indicates potential clinical benefits of oral FC in terms of iron supplementation for renal anemia in HD patients.

Publisher Summary Crack tip plasticity, such as stress and strain distribution/redistribution during crack propagation in environments, represented by crack tip strain rate (CTSR), plays a critical role in promoting environmentally assisted crack growth. Crack tip plasticity, in terms of stress/strain distribution, as well as plastic zone size, can enhance crack tip oxidation rates by causing physical degradation of the interfacial oxide film or by promoting mass transport, and/or electron-transfer processes in the crack tip region, and at grain boundaries in the case of intergranular stress corrosion cracking. Quantification of crack tip mechanics is critical for determining oxidation/deformation interactions and subsequent crack growth rate (CGR) formulations. The results of CGR vs. CTSR for sensitized 304 SS with or without warm rolling, for alloy 182 weld metal in simulated boiling water reactors environments, and for alloy 600 in simulated pressurized water reactors (PWRs) environments show a consistency between crack growth and the deformation/oxidation interaction represented by CTSR. The deformation by cold or warm rolling can significantly increase CTSR and thus accelerate stress corrosion cracking growth in both boiling water reactors and PWR environments, for both stainless steels and, Ni-base alloys.