Biomedical subjects

J J Leng

Publications and source records attributed to J J Leng.

At least 55 records · Page 3Linked to original sources

PubMed1986

[Metabolic activation of benzo(a)pyrene by human amniotic fluid].

The in vitro activation of benzo(a)pyrene was studied in amniotic fluid from ten 4-month pregnant women. Benzo(a)pyrene monooxygenase and epoxide hydrolase activities were in the same range in amniotic fluid as in human liver. Glutathione epoxide transferase activity was markedly lower than in hepatocytes. Human amniotic fluid also catalyzed the formation of hydrocarbon metabolites mutagenic to Salmonella typhimurium TA98 (Ames system). Profiles of amniotic fluid aromatic hydrocarbons from non smokers exhibited low benzo(a)pyrene concentration (less than 0.1 ng/ml).

Amniotic Fluid↗

PubMed1986

[Management of pregnancy at risk: evaluation of fetal movements, determination of total plasma estriol and placental lactogen hormone in relation to fetal heart rhythm].

The authors studied 50 at-risk pregnancies to decide how useful fetal movements were prognostically. They compared this method with electronic measurements of fetal cardiac rhythm. The results show that it is both sensitive and specific. The levels of total oestriols and of plasma placental lactogen hormone when compared with the fetal heart rhythm are just as specific and sensitive.

Estriol↗

PubMed1985

[Transplacental transfer of 5 antibiotics by in vitro human placental perfusion].

Transplacental transfer of 5 semi-synthetic penicillins which act on Gram + and Gram - bacteria were studied by in vitro perfusion of the human placenta. These penicillins were: amoxicillin, apalcillin, mezlocillin, piperacillin and ticarcillin. Placental transfer of these 5 antibiotics varies between 5 and 7% of the maternal concentration. Amoxicillin 7,62% - apalcillin 5,66% - mezlocillin 5,4% - piperacillin 7,37% - ticarcillin 4,86%. The reasons for such low transfer and the clinical repercussions of these results are discussed by the authors.

Amoxicillin↗

PubMed1983

[Preliminary in vitro study of the transplacental passage of spiramycin].

Spiramycin, a true macrolide antibiotic, is the only agent which can be used for the preventive treatment of congenital toxoplasmosis. It gives very high levels in the human placenta, but its transplacental transfer is likely to be very poor, so that it may not cure an already infected foetus. We studied the human placental transfer of spiramycin by an in vitro perfusion model of placentas obtained at term of uncomplicated pregnancies. The transfer rate of spiramycin was found to be close to 9% of the maternal circulating concentrations and 23% of the antipyrine transfer rate, which is only flow-limited. Possible therapeutic implications of these results are discussed.

Antipyrine↗

PubMed1981

[Trans-placental transfer of four anti-inflammatory agents. A study carried out by in vitro perfusion (author's transl)].

Phenylbutazone, oxyphenylbutazone, ketoprofene and indocid transfer through the placenta (TFp) were studied by perfusing a placental cotyledon at term in vitro. These drugs were used in the therapeutic doses that are employed in human clinical practice. Antipyrine was used as a control material to check the validity of the perfusion in each experiment. TFp of phenylbutazone was 25.83 per cent +/- 0.46, of oxyphenylbutazone 22.48 per cent +/- 1.38, of ketoprofene 35.574 per cent +/- 0.95 and of indomethacin 36.19 per cent +/- 0.26. The authors point out the advantages and the possible dangers of non-steroid anti-inflammatory agents used in pregnant women. They prefer the use of ketoprofene of indomethacin because the anti-prostaglandin properties of ketoprofene are greater although the TFp is significantly less.

Anti-Inflammatory Agents↗

PubMed1980