Biomedical subjects

L Stramare

Publications and source records attributed to L Stramare.

3 recordsLinked to original sources

PubMed1999

Steady state maternal-fetal leucine enrichments in normal and intrauterine growth-restricted pregnancies.

The aim of this study was to compare the fetal/maternal (F/M) leucine-enrichment ratio in normal (AGA) and intrauterine growth-restricted (IUGR) pregnancies at the time of fetal blood sampling (FBS). A maternal primed-constant infusion of L-[1-13C]-leucine was given in six AGA and 14 IUGR pregnancies, divided into three groups according to the pulsatility index (PI) of the umbilical artery and to fetal heart rate (FHR): group 1 (normal FHR and PI, four cases); group 2 (normal FHR and abnormal PI, five cases); and group 3 (abnormal FHR and PI, five cases). Maternal arterialized samples were taken at time zero and every 20 min for 125+/-7 min. Umbilical venous samples were obtained after 114+/-42 min of infusion. Under steady state conditions, there was a significant linear relationship between maternal leucine disposal rate and maternal leucine concentration. The comparison of fetal to maternal leucine enrichment showed a progressive dilution of the fetal enrichment relative to the mother between AGA and IUGR of group 1 (0.89 versus 0.78, p < 0.02), group 2 (0.71, p < 0.001), and group 3 (0.62, p < 0.001), and also among the three IUGR groups. The F/M leucine molar percent enrichment (MPE) ratio showed a positive correlation with the umbilical venous oxygen content and an inverse correlation with fetal lactate concentration. We conclude that the dilution in the fetal/maternal leucine-enrichment ratio correlates with the severity of growth restriction and reflects decreased transplacental leucine flux and/or increased protein breakdown within the fetoplacental compartments.

Adult↗

PubMed1998

Rapid solid-phase extraction method for automated gas chromatographic-mass spectrometric determination of nicotine in plasma.

The aim of this study was to develop a simple, rapid and sensitive assay of nicotine in plasma for automated gas chromatographic-mass spectrometric analysis. Biological samples were extracted using pre-packed Extrelut-1 columns with 5 ml of ethyl acetate. Quantitative analysis was done using deuterium-labelled nicotine as internal standard. The limit of quantitation was 0.5 ng in 1-ml plasma samples. Precision was ranging from 13.3% to 1.64% (R.S.D.) depending on the concentration, while the deviation was 4.16%. This method has been used for determination of nicotine bioavailability from new, low-dosage, nicotine chewing gum strips.

Adult↗

PubMed1996

Validity of self-reported smoking habits in pregnancy: a saliva cotinine analysis.

BACKGROUND: We examined the validity of self-reported cigarette smoking during the third trimester of pregnancy using saliva cotinine as a marker. METHODS: Eligible for the study were 109 pregnant women attending the outpatient Prenatal Service of the Luigi Mangiagalli Clinic (the largest maternity clinic in Milan) for routine prenatal visits during the third trimester of pregnancy on twenty days in 1994. Women self-reporting current smoking or quitting smoking in pregnancy were asked to provide a saliva sample. Cotinine concentration was analyzed and classified as follows: cotinine not detectable, not probable nicotine use or passive exposure; cotinine <10 ng/ml, not probable nicotine use/probable passive exposure; cotinine, > or = 10 ng/m, probable occasional or regular nicotine use. RESULTS: A total of 57 (52.3%) women were non-smokers at conception and were excluded from any subsequent analysis. Of the remaining 52 women, 25 self-reported quitting smoking in pregnancy and 27 were current smokers. Saliva cotinine levels were below 10 in 20 of the 25 subjects reporting quitting smoking in pregnancy. The five cases with cotinine > or = 10 reported a husband smoking more than 10 cigarettes per day. Among the 26 current smokers, seven had a cotinine level <10 ng/ml (four reported smoking fewer then five cigarettes per day and two reported smoking five or more per day); in 20 cases the cotinine value was > or = 10 ng/ml. CONCLUSIONS: These findings provide evidence of a satisfactory validity of self-reported smoking habits in pregnancy.

Adolescent↗