1.Alterations in malondialdehyde levels and laboratory parameters among methamphetamine abusers.
Suriyaprom K;Tanateerabunjong R;Tungtrongchitr A;Tungtrongchitr R J Med Assoc Thai. 2011 Dec;94(12):1533-9.
OBJECTIVE: ;To determine the concentrations of malondialdehyde, biochemical, and hematological parameters among methamphetamine abusers compared with a healthy control group and to evaluate the association between malondialdehyde and biochemical-hematological parameters.;MATERIAL AND METHOD: ;The concentrations of malondialdehyde, lipids, liver enzymes, albumin, blood urea nitrogen, creatinine, and hematological measurements were determined in 60 methamphetamine abusers and 60 controls.;RESULTS: ;Significantly higher levels of malondialdehyde were found in the methamphetamine abusers than the controls [2.45 (2.12-2.81) vs. 1.41 (1.15-2.08)]. The levels ofalanine aminotransferase and alkaline phosphatase and white blood cell and platelet counts of the methamphetamine abusers were significantly elevated (p-value < 0.05) compared with the controls. Meanwhile, the levels of hemoglobin, hematocrit, albumin and body mass index were significantly lower among the methamphetamine-abusing group than the control group (p-value < 0.05). It was found that higher numbers of methamphetamine tablets per day were associated with higher malondialdehyde concentrations in methamphetamine abusers, and that malondialdehyde concentration inversely correlated with albumin level (r = -0.
2.Specificity and stereospecificity of alpha-chymotrypsin.
Ingles DW;Knowles JR Biochem J. 1967 Aug;104(2):369-77.
1. The optically pure p-nitrophenyl esters of the d and l enantiomers of N-acetyl-tryptophan, N-acetylphenylalanine and N-acetyl-leucine, and the p-nitrophenyl ester of N-acetylglycine, have been prepared. 2. These materials are all substrates of alpha-chymotrypsin, and the rates of deacylation of the corresponding acyl-alpha-chymotrypsins have been determined. 3. As the size of the amino acid side chain increases, the l series deacylate progressively faster than the N-acetylglycyl-enzyme, and the d series progressively more slowly. 4. The results are interpreted in terms of a three-locus model of the enzyme's active site, which accounts for the interrelationship between substrate specificity and stereospecificity observed. 5. The concepts of negative specificity and of specificity saturation are introduced.
3.Requirement of initiation factor 3 in the initiation of polypeptide synthesis with N-acetylphenylalanyl-tRNA.
Bernal SD;Blumberg BM;Nakamoto T Proc Natl Acad Sci U S A. 1974 Mar;71(3):774-8.
Initiation factor 3 is required, along with initiation factors 1 and 2, for the incorporation of N-acetylphenylalanine into polypeptides and the formation of N-acetylphenylalanylpuromycin. Initiation factor 3 also strongly stimulates the binding of N-acetylphenylalanyl transfer RNA to isolated 30S ribosomal subunits. Phosphocellulose fractions of initiation factor 3 were found to catalyze N-acetylphenylalanine incorporation differentially with different synthetic messenger RNAs not containing any codons for N-formylmethionine. The results suggest that ribosomes recognize the initiator codon only through the initiator transfer RNA.