KINNERSLEY AND PETERS [1929, 1930] have demonstrated that there is an increase in the lactic acid content of the brain of the pigeon in polyneuritis (induced by feeding on polished rice) and that the increase is particularly marked in the midand hind-brain. They were inclined to interpret their results as an indication that a local defect in the metabolism of this lower part of the brain was re...

The active site cysteine of pig liver thioltransferase was identified as Cys22. The kinetics of the reaction between Cys22 of the reduced enzyme and iodoacetic acid as a function of pH revealed that the active site sulfhydryl group had a pKa of 2.5. Incubation of reduced enzyme with [1-14C]cysteine prevented the inactivation of the enzyme by iodoacetic acid at pH 6.5, and no stable protein-cyst...

The reaction of iodoacetic acid with bovine lutropin (luteinizing hormone) at pH 3.0 was specific for methionine residues; it was slow and reached its equilibrium after 12 h at 37 degrees C. The number of modified methionine residues increased proportionately with the amount of the alkylating reagent in the reaction mixture. In the presence of a 20-fold molar excess of iodoacetic acid with resp...

Accumulating evidence suggests that photoreceptor cells play a previously unappreciated role in the development of early stages of diabetic retinopathy, but the mechanism by which this occurs is not clear. Inhibition of oxidative stress is known to inhibit the vascular lesions of early diabetic retinopathy, and we investigated whether the diabetes-induced oxidative stress in the retina emanates...

In contrast to absorption of the hexoses, sorbose and mannose, and of the pentoses, xylose and arabinose, absorption of the physiologically important hexoses, galactose, glucose, and fructose, by the mucosa of the small intestine is a comparatively rapid process, and does not proceed in accordance with the laws of diffusion (1, 33). Absorption of these sugars is therefore spoken of as active, i...