A double-blind randomised comparison of ropivacaine 0.5%, bupivacaine 0.375% - lidocaine 1% and ropivacaine 0.5% - lidocaine 1% mixtures for cataract surgery.

This study evaluated the efficacy and side-effects of plain ropivacaine compared with ropivacaine-lidocaine and bupivacaine-lidocaine mixtures for peribulbar blocks in cataract surgery. Ninety patients were randomly allocated to three groups and received peribulbar blockade using one of the three solutions. Speed of onset and quality of blockade were assessed using akinesia, surgical satisfaction and patient satisfaction. Complications and cardiovascular side-effects were noted. There was a slower onset of akinesia using ropivacaine alone, although at 10 min after injection all groups were equal in this respect. There was no difference in surgical or patient satisfaction between the groups. There were no differences in pain on injection, preblock and postblock blood pressure, heart rate or oxygen saturation. The optimal time to surgical incision after peribulbar blockade is not less than 15 min and plain ropivacaine fulfils this criterion.

Citrobacter diversus ventriculitis and brain abscesses in an adult.

A case of Citrobacter diversus brain abscesses following urinary infection in an adult is described. The patient was treated with surgical drainage, netilmicin and cefotaxime. Citrobacter species CNS infection is discussed.

Role of an immunisation advisory clinic.

An immunisation advisory clinic was set up in Redbridge in 1984 to try to allay the anxieties of parents and doctors about vaccination against whooping cough and measles. The parents agreed to vaccination for 54 out of 67 children against whooping cough and 54 out of 57 against measles. Most of the 117 children who were referred to the clinic probably would not have been vaccinated, although only two had valid contraindications.

Antibody response and clinical reactions in children given measles vaccine with immunoglobulin.

Antibody responses and clinical reactions to three measles vaccines (Attenuvax, Mevilin, and Rimevax) injected into the opposite arm to immunoglobulin were assessed in 45 children with brain disorders making them susceptible to fits if given measles vaccine alone. In this small study no unacceptable reactions occurred and in only three cases was the antibody response minimal or absent. More children in this special category should be considered for vaccination against measles in this way.

Genomic clones of Aspergillus nidulans containing alcA, the structural gene for alcohol dehydrogenase and alcR, a regulatory gene for ethanol metabolism.

Our aim was to obtain from Aspergillus nidulans a genomic bank and then clone a region we expected from earlier genetic mapping to contain two closely linked genes, alcA, the structural gene for alcohol dehydrogenase (ADH) and alcR, a positive trans-acting regulatory gene for ethanol metabolism. The expression of alcA is repressed by carbon catabolites. A genomic restriction fragment characteristic of the alcA-alcR region was identified, cloned in pBR322, and used to select from a genomic bank in lambda EMBL3A three overlapping clones covering 24 kb of DNA. Southern genomic analysis of wild-type, alcA and alcR mutants showed that the mutants contained extra DNA at sites near the center of the cloned DNA and are close together, as expected for alcA and alcR. Transcription from the cloned DNA and hybridization with a clone carrying the Saccharomyces cerevisiae gene for ADHI (ADC1) are both confined to the alcA-alcR region. At least one of several species of mature mRNA is about 1 kb, the size required to code for ADH. For all species, carbon catabolite repression overrides control by induction. The overall characteristics of transcription, hybridization to ADC1 and earlier work suggest that alcA consists of a number of exons and/or that the alcA-alcR region represents a cluster of alcA-related genes or sequences.

Purification and preliminary characterization of alcohol dehydrogenase from Aspergillus nidulans.

Aspergillus alcohol dehydrogenase is produced in response to growth in the presence of a wide variety of inducers, of which the most effective are short-chain alcohols and ketones, e.g. butan-2-one and propan-2-ol. The enzyme can be readily extracted from fresh or freeze-dried cells and purified to homogeneity on Blue Sepharose in a single step by using specific elution with NAD+ and pyrazole. The pure enzyme has Mr 290 000 by electrophoresis or gel filtration; it is a homopolymer with subunit Mr 37 500 by electrophoresis in sodium dodecyl sulphate; its amino acid composition corresponds to Mr 37 900, and the native enzyme contains one zinc atom per subunit. The enzyme is NAD-specific and has a wide substrate activity in the forward and reverse reactions; its activity profile is not identical with those of other alcohol dehydrogenases.

A polyamine-sensitive mutant of Aspergillus nidulans.

A mutation designated spsA1 has been induced in the putrescine (puA2) auxotroph of Aspergillus nidulans which enables this mutant to grow on low concentrations of spermidine in place of putrescine. In addition, the spsA1 mutant, irrespective of putrescine requirement, is abnormally sensitive to high concentrations of spermidine, spermine or the polyamine analogue methylglyoxal bis(guanylhydrazone). When spsA1 strains are grown on medium containing spermidine, uptake of the polyamine continues at a high level for a longer period than in the wild-type and leads to a doubled intracellular spermidine pool. A similar increase in the intracellular spermine pool results from growth on spermine.

The regulation of urease activity in Aspergillus nidulans.

Aspergillus nidulans can utilize urea as a sole source of nitrogen but not as a carbon source. Urea is degraded by a urease. Mutation at any one of three genes, ureB, ureC, and ureD, may result in deficient urease activity. The ureB gene is closely linked to ureA, the structural gene for the urea transport protein. The heat lability of ureB- revertant strain, intragenic complementation tests, and the linkage of ureB to ureA suggest that ureB is the urease structural gene. The ureD gene is probably involved in the synthesis or incorporation of a nickel cofactor essential for urease activity. The function of the ureC gene is not known. Urease is not induced but is subject to nitrogen regulation. The urease activities of ammonium-derepressed mutants show that the effector of nitrogen regulation is more likely to be glutamine than ammonium. When glutamine is present in the medium, urease appears to be inactivated by some means which does not involve a newly synthesized protease or a direct interaction between glutamine and urease.