Use of gas chromatography/mass spectrometry with positive chemical ionization for the determination of opiates in human oral fluid.

An analytical method for the simultaneous determination of codeine, morphine and 6-acetylmorphine (6AM) in human oral fluid was developed. The method involves liquid-liquid extraction in Toxitubes A, derivatization with 99:1 (v/v) N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA)/trimethylchlorosilane (TMCS), and gas chromatography/mass spectrometry with positive chemical ionization (GC/PCI-MS) determination. The detector response was linear over the concentration range 30-500 ng/mL with coefficients of correlation higher than 0.

Quantitation of cocaine and its major metabolites in human saliva using gas chromatography-positive chemical ionization-mass spectrometry (GC-PCI-MS).

An analytical method for the simultaneous determination of cocaine (COC) and its major metabolites, ecgonine methyl ester (EME) and benzoylecgonine (BEG), in saliva was developed. The method involves liquid-liquid extraction in Toxitubes A, derivatization with 99:1 (v/v) N,O-bis-trimethylsilyltrifluoroacetamide (BSTFA)/trimethylchlorosilane (TMCS) and gas chromatography-mass spectrometry (GC-MS) determination. The detector response thus obtained is linear over the range 25-1000 ng/mL, with a reproducibility better than 93% and a recovery close to 100% for the three analytes.

Influence of concomitant drugs on methadone elimination half-life in patients under a maintenance treatment.

Methadone elimination half-life was determined in 18 patients under maintenance treatments and found to range from 2.05 to 49.6 h.

Effects of intravenous digoxin on pulmonary venous and transmitral flows in patients with chronic heart failure of different degrees.

Acute effects of digoxin on diastole were evaluated noninvasively by combining data simultaneously obtained by Doppler echocardiograms (echo-Doppler) of transmitral and pulmonary venous flow curves in 38 patients with dilated and failing hearts, who had been stable for at least 7 days before the study. According to the resting ejection fraction (EF), patients were subdivided into Group 1 (EF < 30%: n = 20, mean EF values 23 +/- 8%) and Group 2 (EF > or = 30%: n = 18, mean EF values 40 +/- 3%). Significant differences were observed at rest between the two groups in both transmitral (shorter deceleration time and isovolumic relaxation time and increased peak E and E/A ratio in Group 1 vs.

Failure of atrial natriuretic factor to increase with saline load in patients with dilated cardiomyopathy and mild heart failure.

To investigate whether the response of atrial natriuretic factor (ANF) to volume expansion is impaired in the early stages of dilated cardiomyopathy, the effects of saline load (SL; 0.25 ml/kg.min for 120 min) were assessed in 12 patients with dilated cardiomyopathy and asymptomatic to mildly symptomatic heart failure (HF) and in nine normal subjects (N).