The derivatization of cysteine-containing peptides with benzoquinone compounds is rapid, quantitative and specific in acidic media. The conversion of cysteines into hydrophobic benzoquinone-adducted residues in peptides is used here to alter the chromatographic properties of cysteinyl peptides during liquid chromatography separation. The benzoquinone derivatization is shown to allow the accurat...

Organophosphorus (OP) nerve agents represent a class of highly toxic chemical warfare banned by the Chemical Weapons Convention. Nevertheless, in past few years they have been used repeatedly for warfare, assassination and attempted murder. In addition, chemically related OP pesticides were frequently suicide may be deployed terroristic attacks. Therefore, sensitive selective bioanalytical meth...

Title: Association Between Aflatoxin B1 Albumin Adduct Levels and Tuberculosis Infection Among HIV+ Ghanaians. Background: Aflatoxin exposure has been shown to cause cell-mediated immune suppression and enhance HIV viral replication. Such immune suppression from aflatoxin can impair resistance to both infectious diseases and chronic infections. Methods: Hazard ratios (HRs) with 95% confidence i...

Aminoguanidine inhibits the formation of advanced glycation end-products, and has been extensively examined in animals. However, administration of aminoguanidine decreases the hepatic content of pyridoxal phosphate. In order to avoid this problem, we developed an aminoguanidine pyridoxal Schiff base adduct and examined its efficacy in vitro as well as in a model of diabetic nephropathy. Mice wi...

The biomarker "ischemia-modified albumin" (IMA), measured by the albumin-cobalt-binding assay (ACB assay), is the only FDA-approved biomarker for early diagnosis of myocardial ischemia. On the basis of the hypothesis that high levels of free fatty acids are directly responsible for reduction in cobalt binding by albumin, chemically defined model systems consisting of bovine serum albumin, Co(2+...

OBJECTIVES 1,5-Naphthalene diisocyanate (NDI) is used in the plastic industry as a curing agent. 1,5-Naphthalene diisocyanate is classified as a sensitizing agent. The objective of this study has been to develop biomonitoring methods for the evaluation of exposure to NDI. MATERIAL AND METHODS We obtained blood and urine samples from a group of 20 male workers exposed to NDI. The workers answe...

Increased research efforts are currently focusing on Atlantic cod (Gadus morhua) and its significance for monitoring the contaminant situation in marine environments. Polycyclic aromatic hydrocarbons (PAHs) are well known toxic and carcinogenic compounds, thus continuous monitoring is required to ensure ecosystem sustainability and human food safety. A sensitive biomarker of PAH exposure in hum...

Treatment of acetyl- 1,4-benzoquinone with isoprene gave the corresponding regioselective adduct (I). Rearrangement of the adduct (1) in pyridine and methanol gave 2-acetyl-5, 8-dihydro-6-methyl- 1,4-dihydroxynaphthalene (2). Silver oxide oxidation of the rearranged product (2) gave 2-acetyl-5,8-dihydro- 6-methyl- 1,4naphthalenedione (3). Regioselective addition of trans-piperylene to this...

OBJECTIVE To investigate the association between birth outcomes and blood levels of aflatoxin B(1) (AFB1)-lysine adduct in pregnant women in Kumasi, Ghana. METHOD A cross-sectional study of 785 pregnant women attending antenatal clinic was conducted. Aflatoxin B(1) (AFB(1))-lysine adduct levels were determined by high performance liquid chromatography (HPLC) on blood taken after delivery. The...