The coenzyme A-synthesizing protein complex and its proposed role in CoA biosynthesis in bakers' yeast.

An improved procedure is described for the recovery and purification of the coenzyme A-synthesizing protein complex (CoA-SPC) of Saccharomyces cerevisiae (bakers' yeast). The molecular mass of the CoA-SPC, determined prior to and following its purification, is estimated by Sephacryl S-300 size exclusion chromatography to be between 375,000-400,000. Two previously unreported catalytic activities attributed to CoA-SPC have been identified. One of these is CoA-hydrolase activity which catalyzes the hydrolysis of CoA to form 3',5'-ADP and 4'-phosphopantetheine, and the other is dephospho-CoA-pyrophosphorylase activity which catalyzes a reaction between 4'-phosphopantetheine and ATP to form dephospho-CoA. The dephospho-CoA then reacts with ATP, catalyzed by the dephospho-CoA-kinase, to reform CoA. This sequence of reactions, referred to as the CoA/4'-phosphopantetheine cycle, provides a mechanism by which the 4'-phosphopantetheine can be recycled to form CoA. Each turn of the cycle utilizes two mol of ATP and produces one mol of ADP, one mol of PPi, and one mol of 3',5'-ADP. Other than the hydrolysis of CoA by CoA-SPC, the 4'-phosphopantetheine for the cycle apparently could be supplied by alternate sources. One alternate source may be the conventional pathway of CoA biosynthesis. Intact CoA-SPC has been separated into two segments. One segment is designated apo-CoA-SPC and the other segment segment is referred to as the 10,000-15,000 M(r) subunit. The 5'-ADP-4'-pantothenic acid-synthetase, 5'-ADP-4'-pantothenylcysteine-synthetase, 5'-ADP-4'-pantothenylcysteine-decarboxylase, and CoA-hydrolase activities reside in the apo-CoA-SPC segment of CoA-SPC. Whereas the dephospho-CoA-kinase and the dephospho-CoA-pyrophosphorylase activities reside in the 10,000-15,000 M(r) subunit. Thus, the 10,000-15,000 M(r) subunit mimics the bifunctional enzyme complex that catalyzes the final two steps in the conventional pathway of CoA biosynthesis.

Comparative study of flurbiprofen and morphine for postsurgical gynecologic pain.

This single-dose, double-blind, randomized, placebo-controlled study assessed the efficacy and safety of 50 mg of flurbiprofen (Ansaid, Upjohn) in the relief of postoperative pain following cesarean section, as well as vaginal or abdominal hysterectomies. Results show that both 50 mg of oral flurbiprofen and 10 mg of intramuscular morphine sulfate were significantly superior to placebo in 161 patients with respect to pain intensity after medication, pain relief scores, need for additional analgesia, and overall clinical evaluation of pain relief. By two hours after treatment, there were no significant differences between morphine sulfate and flurbiprofen in terms of pain intensity or degree of pain relief. According to investigators' global evaluations of efficacy, both active treatments were statistically superior to placebo. The only adverse reaction occurred in the morphine treatment group. Flurbiprofen administered orally for the relief of moderate to severe pain following major gynecologic surgery appears to be equal to morphine sulfate and superior to placebo in efficacy and safety. Unlike morphine, flurbiprofen is a nonparenteral, uncontrolled substance, and thus patient acceptance is improved while nursing time is decreased.

Prophylactic transfusions in pregnant patients with sickle hemoglobinopathies: benefit versus risk.

Pregnancy in patients with sickle cell disease has been a significant threat to maternal survival and good reproductive outcome. In the past several years, statistics for both maternal and perinatal outcome have improved. There is controversy, however, as to whether this improvement has resulted from the use of maternal transfusions or the aggressive and intense medical management afforded these patients in recent years. This study details the reproductive experience of 80 pregnant patients with significant hemoglobinopathies, 75 of whom were treated with partial prophylactic exchange transfusions during gestation. Each of the 75 patients who completed the protocol received 2 transfusions using buffy coat-poor washed packed red cells. The results show that there was no maternal mortality and a significant improvement in maternal morbidity compared to previous studies. There was also a significant improvement in fetal salvage, with a perinatal mortality rate of 26 per 1000. In addition, there were fewer premature and low birth weight infants as compared to other studies in the literature. Although these results were favorable, only a randomized multicentered study in the future will detail advantages and disadvantages of such therapy in the gravid sickle cell patient compared to intensive medical treatment without transfusion.

Effect of corticosteroids and fetomaternal disorders on the L:S ratio.

Hydrocortisone or placebo was administered to 126 women at risk for premature delivery who had immature lecithin:sphingomyelin (L:S) ratios in order to induce early surfactant synthesis. In 70 subjects (37 steroid-treated patients, 33 controls), L:S ratio was determined a second time between 9 hours and 7 days after therapy had been initiated. The treatment group showed a significant increase in the L:S ratio when compared to those who received the placebo. Moreover, patients who had fetomaternal disorders that accelerated or delayed lecithin production were also found to have increased L:S ratios after treatment. Fewer newborns developed respiratory distress syndrome (RDS) in the treatment group than in the control group and those in the former category who were affected by RDS had a milder clinical course.

Amniotic fluid tests for fetal maturity in normal and abnormal pregnancies.

The lecithin-sphingomyelin (L/S) ratio is acknowledged to be superior to most procedures for predictinf fetal lung maturity in normal pregnancy. In complicated gestations, however, errors have been reported. This study involves 686 normal gestations and 389 pregnancies complicated by fetomaternal diseases. The L/S ratio, creatinine level, and percent of fat-staining cells were measured in samples of amniotic fluid from these patients. The results showed good correlation of all three tests with fetal maturity as measured by weight, Dubowitz criteria, and incidence of respiratory distress syndrome in the normal patients. In the complicated pregnancies, however, the creatinine was unacceptable in up to 30% of the cases. The L/S ratio likewise decreased in accuracy for all parameters of fetal maturity measured. The Nile blue staining of the fetal cells appeared to be the most consistent technic in these cases. A fetal maturity battery comprised of these three assays and other methods of assessing fetal health is advocated in pregnancies complicated by certain disease states.

Nile blue and fetal maturity. Further investigations.

The consistency of results using Nile blue staining of fetal cells in amniotic fluid to estimate fetal maturity has been demonstrated. Recently, evidence to support this method has been published from this laboratory. Several biochemical and technical factors were cited as important to the success of the method. This report deals with further testing of several Nile blue dyes (hydrochloride and sulfate) necessitated by changes in production and federal regulation of this compound. The results show Nile blue hydrochloride (HCl) to be the most superior dye regardless of color index. Buffered solutions (6.6) of Nile blue A (sulfate) improve its performance, but not to levels demonstrated by the HCl preparation. Storage at room temperature adversely affects each dye; however, the sulfate variety appears to be the most unreliable under these circumstances. For best results, it is recommended that Nile blue HCl be used and the solution (buffered or normal) be kept refrigerated.

Purification and characterization of B-protein from human serum.

B-Protein, present in the serum of individuals with cancer, has been purified to electrophoretic homogeneity. The purification procedure consisted of chromatography on Sephacryl S-200, Affi-Gel Blue, Con A--Sepharose 4B, wheat germ lectin--Sepharose and preparative polyacrylamide gel electrophoresis. The molecular weight of B-Protein is estimated to be 100 000 to 120 000. It is a glycoprotein which appears to be composed of two subunits, each with a molecular weight of approximately 52 000. Analytical polyacrylamide gel electrophoresis and analytical ultracentrifugation data indicate that purified B-Protein is homogeneous. Isoelectric focusing studies also show the purified B-Protein to be homogeneous in composition consisting of a single band of pI = 4.8. Amino acid analysis is consistent with this acidic isoelectric point. Other analyses indicate that B-Protein contains 7% carbohydrate and 7% lipid in the form of triglycerides.

Meperidine and normeperidine distribution in the rhesus monkey.

Previous work has shown that both meperidine and normeperidine are transferred across the placenta to the fetus. Little is known in primates, however, about the tissue deposition of these compounds. Four pregnant, dated rhesus monkeys within one week of term were anesthetized for cesarean delivery. An equal mixture of meperidine and normeperidine was administered as an intravenous bolus 10 minutes before delivery (1.25 mg/kg). The infants were then sacrificed at 20 minutes after birth and the concentration of the compounds in various organ systems were analyzed by gas-liquid chromatography and mass spectroscopy (GLC-MS). The infant serum 20 minutes after delivery revealed a meperidine concentration of 2.23 micrograms/ml and a normeperidine level of 0.67 micrograms/ml (3:1). In contrast, the tissues analyzed showed a much higher concentration of the metabolite in the liver (1:7), gallbladder (1:3), and brain (1:2). Other tissues, such as muscle and kidney, demonstrated equal levels of the two compounds. The authors conclude that normeperidine is quickly transferred to fetal tissues and to a greater degree than the parent compound in certain organs. The increased distribution, particularly in the brain, could account for the toxic actions in the cerebrum of the derivatives of meperidine.

Pharmacokinetics of meperidine in pregnancy.

The disposition of meperidine was studied in 11 term pregnant humans after the administration of a single 50 mg intravenous dose of meperidine through 48 h post-injection. Half-lives of the rapid and terminal elimination phases were calculated as 2.3 and 13.3 h, respectively. These values are much greater than previously reported half-lives which were based on data collected over less than 8 h after injection. An accurate value for t1/2 beta may be particularly important in sequential dosing of analgesic medication. These pharmacokinetic constants calculated on data collected through 48 h in this study may have important clinical correlates.

Adjunctive antibiotic treatment of women with preterm rupture of membranes or preterm labor.

Subclinical infection is associated with preterm rupture of the membranes (PROM) and preterm labor (PTL) in many cases. It was hypothesized that antibiotic treatment might delay delivery and/or decrease infectious morbidity in those with PROM or PTL. Patients from 19 to 34 weeks with PROM and no labor or PTL with intact membranes (but not both) were separately randomized to receive ampicillin versus placebo in addition to usual therapy. There were 36 women with PTL (21 ampicillin/15 placebo) and 84 with preterm PROM (41 ampicillin/43 placebo). Demographically, the treatment and placebo groups were similar. Outcome variables analyzed included delivery delay after treatment, maternal chorioamnionitis/endometritis, Apgar score, neonatal infection, or respiratory distress, and hospital stay. There were no significant differences between the ampicillin and placebo groups in those with PTL or preterm PROM as it concerned outcome parameters. Adjunctive ampicillin used for treatment of idiopathic PTL or preterm PROM was not beneficial in this study.

Meperidine and normeperidine metabolism in the rhesus monkey.

Meperidine and its principle metabolite, normeperidine, were given intravenously to four non-human primates prior to cesarean delivery in an equivalent dose for human parturients. The status of the infants regarding neonatal depression was assessed at delivery. Repeated blood samples from both the mother and the neonate were obtained over a period of 4 days. The levels of meperidine and normeperidine were analyzed. The results showed that the metabolism of meperidine and normeperidine in the non-human primate was essentially the same as that observed in the human parturient. In addition, normeperidine appeared to be more toxic than meperidine to the neonate. Finally, there does not appear to be an evidence for neonatal metabolism of meperidine to normeperidine.