BACKGROUND Gambogic acid (GA), a potent anticancer agent, is limited in clinical administration due to its poor water solubility. The aim of this study was to explore a drug delivery system based on magnetic Fe(3)O(4) nanoparticles (MNP-Fe(3)O(4)) conjugated with GA to increase water solubility of the drug and enhance its chemotherapeutic efficiency for pancreatic cancer. METHODS GA was conju...

Iron(III)-reducing bacteria have been demonstrated to rapidly catalyze the reduction and immobilization of uranium(VI) from contaminated subsurface sediments. Thus, these organisms may aid in the development of bioremediation strategies for uranium contamination, which is prevalent in acidic subsurface sediments at U.S. government facilities. Iron(III)-reducing enrichment cultures were initiate...

The iron cycle in aquatic environments involves the reduction of ferric iron (Fe(III)) followed by the oxidation of ferrous iron (Fe(II)). Under natural conditions these reactions are microbially catalyzed. The reduction of Fe(III) is thought to be one of the most important microbially mediated processes in aquatic systems. Fe(II) tends to be soluble and mobile in water, while Fe(III) tends to ...

Recent studies of bacterial Fe(II) oxidation at circumneutral pH by a newly-isolated lithotrophic β-Proteobacterium (strain TW2) are reviewed in relation to a conceptual model that accounts for the influence of biogenic Fe(III)-binding ligands on patterns of Fe(II) oxidation and Fe(III) oxide deposition in opposing gradients of Fe(II) and O2. The conceptual model envisions complexation of Fe(II...

Seasonal variations in pore water and solid phase geochemistry were investigated in urbanized minerotrophic peat sediments located in southwestern Michigan, USA. Sediment pore waters were collected anaerobically, using pore water equilibrators with dialysis membranes (“peepers”) and analyzed for pH, alkalinity, dissolved PO−3 4 , NH + 4 , S −2, SO−2 4 , Fe +3, Fe+2, and Mn+2 at 1–2 cm intervals...

In our study we combine both principles by reducing the dimensionality of organic materials. We show that we are able to form nanostructures with organic molecules on a surface by means of self-organization processes. To achieve this, we used the nanostructure induced on the Au(111)(22×√3) surface by room temperature deposition of iron (<1ML). Fe-islands are formed at the edges of the reconstru...

Ground water systems dominated by iron- or sulfate-reducing conditions may be distinguished by observing concentrations of dissolved iron (Fe(2+)) and sulfide (sum of H(2)S, HS(-), and S(=) species and denoted here as "H(2)S"). This approach is based on the observation that concentrations of Fe(2+) and H(2)S in ground water systems tend to be inversely related according to a hyperbolic function...

Arrays of perpendicular ferromagnetic nanowires have recently attracted considerable interest for their potential use in many areas of advanced nanotechnology. We report a simple approach to create self-assembled nanowires of alpha-Fe through the decomposition of a suitably chosen perovskite. We illustrate the principle behind this approach using the reaction 2La(0.5)Sr(0.5)FeO(3) --> LaSrFeO(4...

Anthocyanins are important compounds for red grape and red wine quality, and can be influenced by supply of nutrients such as nitrogen, phosphorus, potassium, zinc, and iron. The present work aims to gain a better understanding of the effect of iron supply on anthocyanins concentration in grape berries. To this end, own-rooted four-year-old Cabernet Sauvignon grapevines (Vitis vinifera) were fe...

Certain xanthone derivatives, such as these present in mangosteen fruits, show strong antioxidant activity. On the other hand, evidences accumulated that oxidative stress is involved in epileptogenesis. Therefore, the aim of the present study was to estimate total antioxidant capacity (expressed as a ferric reducing antioxidant power FRAP) and evaluate ability to scavenge free radicals (DPPH me...