Zinc Acetate Hydrate Supplementation versus Polaprezinc Supplementation for Improving Hypozincemia in Hemodialysis Patients: A Randomized Clinical Trial.

Zinc supplementation may ameliorate zinc deficiency in maintenance hemodialysis patients; however, no standard protocol has been established. This study aimed to investigate the effects of zinc acetate hydrate (ZAH) and polaprezinc (PPZ) as zinc supplements in hemodialysis patients. We enrolled 75 hemodialysis patients with serum zinc levels <60 µg/dL for this study and randomly assigned Zinc supplementation to these 75 patients: 37 received ZAH (50 mg/day), and 38 received PPZ (34 mg/day). Serum zinc levels of both groups were compared every 4 weeks for 1 year. In both groups, serum zinc levels significantly increased at 4-52 weeks. Serum zinc levels were significantly higher in the ZAH group at 4-12 weeks; however, no significant differences were observed between the groups at 16-52 weeks. Adverse events requiring a reduction in the zinc dose, including copper deficiency, occurred significantly more frequently in the ZAH group. In conclusion, PPZ can safely maintain serum zinc levels for 1 year. ZAH provides rapid zinc supplementation but can cause adverse events.

Nitrogenase activity (acetylene reduction) of an iron-oxidizing leptospirillum strain cultured as a pioneer microbe from a recent volcanic deposit on miyake-jima, Japan.

The genus Leptospirillum is known to dominate acid mine drainage and bioleaching systems. In this paper, we describe the isolation of iron-oxidizing bacteria closely related to Leptospirillum ferrooxidans from an acidic volcanic ash deposit on the island of Miyake (Miyake-jima), Japan. We further show the nitrogenase activity (acetylene reduction) for one (strain C2-1) of the isolates. The deposit harbored 1.2×10(8) total direct count (g dry weight)(-1) and 7.1×10(5) (most-probable-number, MPN) (g dry weight)(-1) of iron-oxidizer. A ferrous iron-limited, aerobic chemostat culture using Leptospirillum HH medium (pH 1.8) was performed to select and isolate the Leptospirillum group. Nine isolates were regarded as pure cultures based on uniform colony morphology on Fe(2+)-containing silica gel plates and absence of growth on 100-fold diluted nutrient broth plates. Six strains examined further shared 99.9-100% identity in 16S rRNA gene sequence with each other. Homology-based searches showed that all of the strains belonged to the Leptospirillum ferrooxidans clade. Strain C2-1 grown in ammonium sulfate-free Leptospirillum HH medium (pH 1.8) showed an initial rate of acetylene reduction of 58 µmol h(-1) (g cell carbon)(-1).