Plasma cholinesterase changes during the puerperium.

Changes in plasma cholinesterase activity during the puerperium were studied in 16 women who received epidural analgesia for labour followed by vaginal delivery, and in five women who underwent elective Caesarean section under epidural analgesia. A consistent fall in cholinesterase activity was demonstrated during the first 2 to 3 days post partum, followed by a rise to approximately normal nonpregnant values by the end of the puerperium. An additional patient who manifested prolonged paralysis following an emergency Caesarean section under general anaesthesia, including a suxamethonium infusion, was also studied.

The primary structure of thioredoxin from the filamentous cyanobacterium Anabaena sp. 7119.

Thioredoxin from the cyanobacterium Anabaena 7119 serves as electron donor to ribonucleotide reductase and as a protein disulfide reductase. This small, heat-stable protein was found to have structural and functional similarities to thioredoxins from both bacterial and mammalian sources. We here report the complete primary structure of Anabaena thioredoxin.

Application of stepwise discriminant analysis in the phenotyping of plasma cholinesterase variants.

Discriminant function analysis has been applied to the results of activity and inhibitor measurements carried out on a series of 229 specimens using benzoylcholine and butyrylthiocholine as substrate. The discriminant function was more effective in differentiating cholinesterase genotypes than either a single test or a combination of two tests.

Stimulation of 3-benzo[a]pyrenyl glucuronide hydrolysis by calcium activation of microsomal beta-glucuronidase.

Rates of hydrolysis of 3-hydroxybenzo[a]pyrenyl glucuronide by microsomal beta-glucuronidase from rat liver were 397 +/- 17 nmol/min per g protein and were half-maximal with about 100 microM substrate. Treatment of rats with phenobarbital or 3-methylcholanthrene, which elevates activities of glucuronosyltransferase(s), lowered rates of hydrolysis of benzo[a]pyrene glucuronide by 25%. Hydrolysis of the glucuronide by microsomal beta-glucuronidase was stimulated by micromolar concentrations of calcium in the range existing in cytosol of hepatocytes (apparent Km approximately 0.

Plasma cholinesterase variants. Family studies of the E1k gene.

The use of RO2-0683 as differential inhibitor has shown that 13% of 181 heterozygotes, believed to be E1uE1a, are in fact E1aE1k. The results indicate that slightly more than 1% of the British population could be homozygote E1kE1k. Analysis of 47 families segregating the E1aE1k phenotype in more than 2 blood relatives is restricted by the inability to differentiate the genotypes E1uE1k and E1kE1k from E1uE1u and E1uE1f.

Isolation and characterization of thioredoxin f from the filamentous cyanobacterium, Anabaena sp. 7119.

Two thioredoxin fractions had previously been reported to occur in Anabaena 7119 by Buchanan and co-workers (Yee, B. C., dela Torre, A.

Effects of storage and repeated freezing and thawing on plasma cholinesterase activity.

Plasma cholinesterase activity, determined using either benzoyl choline or butyrylthiocholine as substrate, is stable for prolonged periods (greater than 12 months) when stored at -20 degrees C. Likewise, repeated freezing and thawing of plasma did not markedly affect cholinesterase activity.

A spectrophotometric assay of phosphoribosyl pyrophosphate synthetase.

A simple spectrophotometric assay of phosphoribosyl pyrophosphate synthetase from human erythrocytes is described. The kinetic properties of the enzyme have been determined and are in good agreement with published results. Conditions for storing haemolysates at -20 degrees C are described.

Comparison of a commercially available assay system with two reference methods for the determination of plasma cholinesterase variants.

For assaying plasma cholinesterase (EC 3.1.1.

The binding of urate to plasma proteins determined by four different techniques.

Venous occlusion in healthy individuals showed no binding of urate under conditions when the expected increased levels of known bound species was demonstrated. Ultrafiltration of serum from 10 healthy controls and five gouty individuals also showed the absence of binding in all cases, as did electrophoretic and chromatographic studies.

Suxamethonium apnoea associated with pregnancy and liver dysfunction in a treated cretin.

A patient, with a history of cretinism, who developed suxamethonium apnoea as a consequence of a reduction in plasma cholinesterase activity secondary to the concurrence of pregnancy and liver dysfunction associated with pre-eclampsia is reported. The patient had a normal phenotype for plasma cholinesterase.

Postoperative ileus, pregnancy-related cholinesterase deficiency and suxamethonium after-pains. A case report.

An account is presented of a patient who developed ileus, of greater or lesser severity, after each of seven operations (including two extra-abdominal and three Caesarean sections). During her most recent pregnancy, reviewed here, her plasma cholinesterase activity was found to be decreased and it remained low until at least the 6th day post-partum. However, as the normal activity had been gained by 6 weeks after delivery, the phenomenon had evidently been pregnancy-related.

Phosphoribosyl pyrophosphate synthetase and glutathione reductase in erythrocytes from hyperuricaemic and gout patients.

The enzymic activities of erythrocyte phosphoribosyl pyrophosphate synthetase (EC 2.7.6.

Studies on the inhibition by propranolol of some human erythrocyte membrane enzymes and plasma cholinesterase.

Human erythrocyte acetylcholinesterase and the plasma cholinesterase variants are not only inhibited by propranolol but have been found to show stereospecificity for its isomers. The erythrocyte enzyme has a greater affinity for the L-isomer than either the racemate or the D-isomer. In contrast the plasma cholinesterases have greater specificity for the D-isomer than the other isomer or racemate.

The diagnosis of Ménétrier's disease.

Two cases of Ménétrier's disease are reported to illustrate the clinical presentation and diagnosis of this unusual condition. The literature has been reviewed of all the reported cases to establish the relative importance of the individual symptomatology, the value of the diagnostic methods, and to highlight the diagnostic pitfalls. Recognition of the barium meal appearances and snare biopsy at gastroscopy may avoid the necessity of diagnostic laparotomy.

Inhibition of the plasma cholinesterase variants by propranolol.

The inhibitory effect of (+/-) propranolol 1.69 x 10(-4)-1.69 x 10(-7) mol litre-1 on normal and atypical plasma cholinesterase variants was investigated.

Malignant hyperthermia and the fluoride-resistant gene.

One hundred and six individuals from 33 families with a history of malignant hyperthermia have been investigated for plasma cholinesterase variants. An increased frequency of the fluoride-resistant gene has been found. Although an adequate explanation for our results is elusive, some hypotheses are discussed.

Differential inhibition of plasma cholinesterase variants using the dibutyrate analogue of pancuronium bromide.

A steroid, the dibutyrate analogue of pancuronium bromide (9.8 X 10(-8)M), has been used as differential inhibitor in the study of the plasma cholinesterase variants. Pancuronium dibutyrate numbers have been measured for 190 individuals, and the mean values for six of the known genotypes, E1uE1u, E1uE1f, E1uE1a, E1fE1a, E1aE1a, and E1fE1f, have been calculated.

A comparison of some methods of phenotyping the plasma cholinesterase variants using benzoylcholine as substrate.

Five differential inhibitors of plasma cholinesterase have been compared using benzoylcholine as substrate. None of the inhibitors (dibucaine, NaF, NaBr, NaCl, or pancuronium dibutyryloxy bromide) could be used singly to resolve all the variants. Better resolution was obtained when two inhibitors were used in conjunction.

Inhibition of the plasma cholinesterase variants by pancuronium bromide and some of its analogues.

Pancuronium bromide, a 3,17-diacetoxy-5 alpha-androstane, and three of its analogues, the 17-desoxy, the 3,17-dibutyryloxy and the 16-N-monoquaternary ammonium derivatives have been used as inhibitors of the usual and atypical plasma cholinesterase variants. In all cases the usual enzyme is more sensitive to inhibition by the substituted steroids than the dibucaine resistant enzyme. The relative affinities of the bis-quaternary ammonium compounds for either enzyme is in the order dibutyryloxy derivative > 17-desoxy derivative greater than or equal to pancuronium bromide.