background: the mapping of the malignization mechanism is still incomplete, but oxidative stress is strongly correlated to carcinogenesis. in our research, using fuzzy logic, we aimed to estimate the oxidative stress related-cancerization risk of the oral potentially malignant disorders. methods: serum from 16 patients diagnosed (clinical and histopathological) with oral potentially malignant d...

A visible light photoredox-catalyzed aldehyde olefin cyclization is reported. The method represents a formal hydroacylation of alkenes and alkynes and provides chromanol derivatives in good yields. The protocol takes advantage of the double role played by trialkylamines (NR3) which act as (i) electron donors for reducing the catalyst and (ii) proton donors to activate the substrate via a proton...

Small molecule rescue of mutant forms of human carbonic anhydrase II (HCA II) occurs by participation of exogenous donors/acceptors in the proton transfer pathway between the zinc-bound water and solution. To examine more thoroughly the energetics of this activation, we have constructed a mutant, H64W HCA II, which we have shown is activated by 4-methylimidazole (4-MI) by a mechanism involving ...

Superoxide reduction by thiolate-ligated [FeII(SMe2N4(tren))]+ (1) involves two proton-dependent steps and a single peroxide intermediate, [FeIII(SMe2N4(tren))(OOH)]+ (2). An external proton donor is required, ruling out mechanisms involving H+ or H-atom abstraction from the ligand N-H. The initial protonation step affording 2 occurs with fairly basic proton donors (EtOH, MeOH, NH4+) in THF. Mo...

When the channel size was reduced to 10-100 nm space, which we call extended-nano space, various unique liquid properties were observed in SiO2 nanochannels for protonic solvents. SiOH groups on the substrate were verified to work as proton donors and affected the liquid property change. However, there is no investigation of the dependence on other proton-donor functional groups. In this presen...

The presence of excited-state buffer-mediated proton exchange reactions influences the steady-state fluorescence signals from dyes in solution. Since biomolecules in general have some chemical groups that can act as proton acceptors/donors and are usually dissolved in buffer solutions which can also behave as appropriate proton acceptors/donors, the excited-state proton exchange reactions may r...

background in the living donor liver transplant setting, the preoperative assessment of potential donors is important to ensure the donor safety. objectives the aim of this study was to identify causes and costs of living liver-donors rejection in the donation process. materials and methods from june 2010 to june 2012, all potential living liver donors for 66 liver transplant candidates were sc...

[reaction: see text] We report for the first time that stoichiometric and even catalytic quantities of weak acids in aqueous solution can very efficiently catalyze amide isomerization in a carefully designed system in which a proton donor is situated so that intramolecular hydrogen bonding to the amide nitrogen is highly favored. Our results provide the first experimental verification that hydr...