Acetonitrile as a possible marker of current cigarette smoking.

Volatile nitriles are present in cigarette smoke. We tested the hypothesis that the presence of any of four nitriles in the blood can serve as a marker of recent cigarette smoking. We determined the sensitivity and specificity of these nitriles as indicators of daily cigarette smoking in 24 smokers (Group A) and 18 non-smokers (Group B), as well as the correlation between intensity of daily smoking and the blood concentration of acetonitrile. A new head space GLC assay method was used. Of the four nitriles, only acetonitrile was present in the blood of any study subject. Acetonitrile was moderately sensitive (67%) and entirely specific (100%) for self-reported daily smoking. There was fair correlation between blood acetonitrile concentration and the average daily number of cigarettes smoked (r2 = 0.39; P = 0.001), and the mean blood acetonitrile concentration was significantly higher (P = 0.03) among subjects with higher (> 10 cigarettes per day) current cigarette exposure (148.3 +/- 18.0 micrograms/l) than among smokers with low or minimal (1-10 cigarettes per day) exposure (43.3 +/- 6.0 micrograms/l). Thus, acetonitrile in blood appears to be highly specific and a moderately sensitive marker of cigarette smoking with a dose-effect relationship. As such, acetonitrile shows promise as a marker of current cigarette exposure.

[Evolution of delta bilirubin/conjugated bilirubins ratio in serum after live transplantation]. / Evolution du rapport delta bilirubine/bilirubines conjuguées dans le sérum après transplantation hépatique.

Serum delta-bilirubin measured in relationship to total bilirubin could be a liver function test in hepatobiliary diseases and even a marker of early rejection after liver transplantation. Delta-bilirubin bound to albumin constitutes with mono and diglucuroconjugates, conjugated bilirubins. We determined the delta-bilirubin/conjugated bilirubins ratio and studied its value in various complications in 16 liver recipients. The results were compared with alanine aminotransferase activity and prothrombin index. Hyperbilirubinemia and a delta-bilirubin/conjugated bilirubins ratio lower than 40% were observed initially. After 15 days, the delta-bilirubin/conjugated bilirubins ratio evolved differently according to the functional state of the graft, which allowed to distinguish three patient groups: in patients with good graft function, the ratio increased regularly to reach 65% or more on the 30th day; in patients with dysfunctional episodes, the ratio was always less than or equal to 40% and did not increase after the 15th day; in other patients, the ratio was lower than 40% and dropped suddenly before death. After liver transplantation, the delta-bilirubin/conjugated bilirubins ratio may be a simple liver function marker. Alone, however, it cannot be used to assess acute rejection.

[Analytical exploration of drug addiction]. / Exploration analytique des toxicomanies.

The natural and synthetic substances most frequently leading to drug addiction are described. They include cannabis, opium and cocaine with their respective derivatives. The authors insist on the problems encountered by analytical chemists when they examine urine samples containing these substances, owing to their metabolic degradation and to interferences between lawful and unlawful drugs. The limitations imposed by these problems to an unambiguous interpretation of the results obtained are defined, but they do not throw any doubt on the value of these investigations.

[Study of bilirubin- albumin binding. I.-In vitro study by partition of bilirubin between an aqueous solution and an immiscible organic solvent (author's transl)]. / Etude de la liaison bilirubine-albumine. I-Etude in vitro par une méthode de partage de la bilirubine entre une solution aqueuse et un solvant organique non miscible à l'eau.

The partition of bilirubin in vitro between water and isobutyl-methylketone/n-heptane mictures is investigated at different pH, in the absence and the presence of albumin. Results are used to compute the concentrations of unbound ionized and unionized bilirubin and the bilirubin-albumin characteristics (association constant K and nomber n of primary binding sites per mole of albumin). The effect of various factors upon these characteristics is discussed.