S-2-Hydroxyacylglutathione hydrolase (glyoxalase II) from rat erythrocytes is a specific thiolesterase. Chemical modification studies with phenylmethanesulfonic acid, N-ethylmaleimide, and 5,5'-dithiobis(2-nitrobenzoate) suggest that glyoxalase II does not have a serine or a cysteine residue at the active site. The effect of pH on the rate of hydrolysis of S-lactoylglutathione indicates the existence of an active-site residue, pK = 8.87, essential for binding of the substrate. Inactivation studies with phenylglyoxal implicate the existence of an active-site arginine residue that also is essential for binding of the substrate. The effects of pD on the rate of hydrolysis of S-lactoylglutathione in D2O give no evidence for general acid-general base catalysis. 1H NMR studies of the glyoxalase II catalyzed hydrolysis of S-mandeloylglutathione show no evidence for a carbanion (E1cB) mechanism. the catalytic role of glyoxalase II appears to involve direct nucleophilic attack of the thiol ester by an active-site histidine residue, based upon inactivation experiments using diethyl pyrocarbonate and photoinactivation with methylene blue.
The demographics, drug habits, and medical complications of a cohort of 1,129 addicts treated at Lexington in the period 1971-1972 were studied. These patients, admitted from 41 different states, had a mean period of addiction of 5.4 years. Over one-third of the sample had engaged in pimping or prostitution, and there were no differences by gender in terms of involvement. Eight-eight percent had shared injection equipment, and surprisingly, 78% admitted to some effort at sterilizing their "works." Hepatitis was the most common associated medical condition: 87% had serologic markers of hepatitis B virus (HBV) infection, 60% had evidence of hepatitis A virus (HAV) exposure, and 47% had abnormal liver function parameters. Gynecomastia was evident in 2% of male subjects. Thirteen percent of the sample had a reactive VDRL assay, but 64% of these were biologically false positive. Subtle abnormalities of immune function were also observed; 18% of the patients had recent unexplained weight loss, 6% had lymphadenopathy, 8% had leukopenia, and 2% had lymphocytopenia. We conclude that both HBV and HAV were important infectious disease risks in these addicts, and that many evidenced deficiencies in immune function well before AIDS became a major public health concern.
The authors assessed the relationship between source of pretreatment income and response to treatment at 6-month follow-up in 165 male veterans admitted to a methadone maintenance treatment program. Subjects were grouped according to whether the majority of their pretreatment income was based on job earnings, public assistance, or criminal activity. Significant improvements in drug use, legal status, and psychological functioning were found in the employed group. The group supported by criminal activity showed the most significant and pervasive improvements, especially in the areas of drug use and family, legal, and employment problems. The group receiving public assistance showed no significant improvements on any of the 16 criterion measures, including drug use.
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