Propofol, frequently used for i.v. induction of anaesthesia in assisted reproduction procedures, has been suspected of damaging oocytes. Concentrations of propofol have recently been shown to increase in follicular fluid during oocyte retrieval. Our study was designed to assess whether exposure to increasing concentrations of propofol has a measurable effect on in-vitro fertilization, cleavage and embryo development. A cohort of 130 women underwent i.v. anaesthesia using propofol and fentanyl. Time of anaesthesia from i. v. injection of propofol was measured, as were the doses of the two drugs. In 32 women expected to have more than 15 oocytes retrieved, first, middle and last oocytes were cultured separately. The mean time from i.v. injection to first follicle aspiration was 200 s. The mean time for the aspiration of each additional oocyte was 17.6 s. In 10 out of 11 cases where follicular fluid concentrations of propofol were measured, there was an increase from the first to the last follicle, but no difference was found in the ratio of mature to immature oocytes. Nor were any differences found in fertilization, cleavage and embryo cell number. In so far as in-vitro development reflects embryo quality, we conclude that the time elapsed between retrieval of the first and last oocyte does not affect oocyte quality.

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UDP-N-acetyl-d-galactosamine:polypeptide N-acetylgalactosaminyltransferases (ppGaNTases) catalyse the initial step of mucin-type O-glycosylation. The activity of bovine ppGaNTase-T1 isoenzyme was inhibited by diethyl pyrocarbonate (DEPC) modification. Activity was partially restored by hydroxylamine treatment, indicating that one of the reactive residues was a histidine. The transferase was protected against DEPC inactivation when UDP-GalNAc and EPO-G, a peptide pseudo-substrate PPDAAGAAPLR, were simultaneously present, while presence of EPO-G alone did not alter DEPC inactivation. However, inclusion of UDP-GalNAc alone potentiated DEPC-inhibition of the enzyme, suggesting that UDP-GalNAc binding changes the accessibility or reactivity of an essential histidine residue. Deletion of the first 56 amino acids (including one hisitidine residue) yielded a fully active secreted form of the bovine ppGaNTase-T1 enzyme. Each of the 14 remaining histidines in the enzyme were mutated to alanine, and the recombinant mutants were recovered from COS7 cells. The mutation of histidine residues His211-->Ala and His344-->Ala resulted in recombinant proteins with no detectable enzymic activity. A significant decrease in the initial rate of GalNAc transfer to the substrate was observed with mutants His125-->Ala and His341-->Ala (1% and 6% of wild-type activity respectively). Mutation of the remaining ten histidine residues yielded mutants that were indistinguishable from the wild-type enzyme. Mutagenesis and SDS/PAGE analysis of all N-glycosylation sequons revealed that positions N-95 and N-552 are occupied by N-linked sugars in COS7 cells. Ablation of either site did not perturb enzyme biosynthesis or enzyme activity.

The aim of this study was to describe busulfan disposition in a pediatric population who underwent bone marrow transplantation (BMT). Busulfan administered dose was 1 mg/kg every 6 h for 4 days. Plasma determinations were performed after the first dosing at 0, 15, 30, 60, 90, 120, 180, 240, 300, and 360 min. A noncompartment analysis model for extravascular absorption was used for the pharmacokinetic analysis. To obtain the area under the concentration-time curve (AUC) within the "therapeutic window" of 1,000-1,200 microM x minutes a busulfan dose adjustment Was performed at the fourth dose. Forty-five busulfan pharmacokinetic analyses were performed in 34 children. Eleven children had their dose adjusted [1.19 +/- 0.14) mg/kg] at the fourth dose and the AUC was monitored at the fifth one. The mean AUC +/- SD after the fifth dose (998.1 +/- 189.2 microM x min) was different (p = .006)from that after the first dose (1 mg/kg) (687.63 +/- 166.43 microM x min). Six children had their first AUC into the "therapeutic window," 17 children had their dose adjusted [1.2 (+/- 0.22) mg/kg], but the "adjusted" AUC was not available. These data suggest that it may be reasonable to recommend a busulfan dose of 1.2 mg/kg to achieve the accepted therapeutic target in children undergoing BMT.