Are carboxyl groups the most acidic sites in amino acids? Gas-phase acidity, H/D exchange experiments, and computations on cysteine and its conjugate base.

Hydrogen-deuterium exchange experiments were carried out on the conjugate base of cysteine with four different deuterated alcohols. Three H/D exchanges are observed to take place in each case, and a relay mechanism which requires the SH and CO2H groups to have similar acidities and subsequently proceeds through a zwitterionic intermediate is proposed. Gas-phase acidity measurements also were carried out in a quadrupole ion trap using the extended kinetic method and in a Fourier transform mass spectrometer by an equilibrium determination.

Case management for patients with poorly controlled diabetes: a randomized trial.

Purpose: To evaluate the effects of a collaborative case management intervention for patients with poorly controlled type 2 diabetes on glycemic control, intermediate cardiovascular outcomes, satisfaction with care, and resource utilization.

Methods: We conducted a randomized controlled trial at two Department of Veterans Affairs Medical Centers involving 246 veterans with diabetes and baseline hemoglobin A(1C) (HbA(1C)) levels >or=7.5%.

Screening by the prostate-specific antigen test: what do the patients know?

Background: Prostate cancer is the most common malignancy in men, and prostate cancer screening is recommended for all men over the age of 50. The use of the prostate-specific antigen (PSA) test for cancer screening is controversial.

Methods: At two different Veterans Administration facilities, outpatients completed a 15-item questionnaire about their knowledge of the PSA test two weeks after receiving a screening test.