Ventral interbody spondylodesis using a new plug-shaped implant.

A new technique for interbody lumbar spondylodesis using a new cancellous metal, plug-shaped construct was performed in 35 cases with spondylolisthesis or lumbar instability. All of these patients have had severe low-back pain for years, some with radicular symptoms and had been treated unsuccessfully for years. In a follow-up study, 28 of these patients were examined after a time-period of 4 to 24 months.

The quaternary structure of Escherichia coli RNA polymerase studied with (scanning) transmission (immuno)electron microscopy.

A model for the quaternary structure of Escherichia coli RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.

Sequence-specific interaction of sigma subunit of E. coli RNA polymerase with DNA.

The interaction of sigma subunit of E. coli RNA polymerase with DNA, either double or single-stranded, and with two inhibitors of RNA synthesis was investigated by using antibodies directed against the subunit. Free sigma subunit was shown to interact with poly(dA), poly(dT), poly(dAC).

Antibodies against the subunits of E. coli RNA polymerase as probes for subunit-specific binding of DNA and other ligands.

Antibodies against the isolated subunits alpha, beta, and beta' of DNA-dependent RNA polymerase from E. coli have been prepared. They have been used to compare the extent of antibody-binding, as measured by complement fixation, to the isolated subunits and to the intact enzyme, in the absence and presence of ligands, such as inhibitors, nucleotides, nucleosides, oligo- and poly-nucleotides, and DNA of different composition.

Interactions of fluorescent cholinergic antagonists with the membrane-bound acetylcholine receptor.

The synthesis of pyrenyl-choline derivatives is reported. The interactions of these compounds with the acetylcholine receptor has been studied in developing chick myotubes in culture and in the adult frog neuromuscular junction with electrophysiological techniques. In vivo, the compounds display the pharmacological characteristics of nicotinic antagonists.

Quaternary structure of DNA-dependent RNA polymerase from Escherichia coli. Measurement of distances by fluorescence energy transfer.

Distances between the subunits in Escherichia coli RNA polymerase (core and holo enzyme) and the rifamycin binding site have been determined using the nonradiative energy transfer technique. The appropriate donor and acceptor labels have been chosen in order to optimize the spectral overlap and maximize the energy transfer. Spacer linked derivatives of rifamycin SV possessing nitrobenzo-oxadiazole groups (energy acceptor) were synthesized for this purpose.

Dissociation kinetics of complexes between the antibiotic rifamycin and DNA-dependent RNA polymerase from Escherichia coli.

Phosphocellulose chromatography was employed to measure the binding of 3-(2-[14C]acetamidoethyl)-thiorifamycin(abbreviated[14C]AcNHEtS-Rif) to RNA polymerase core enzyme. The technique yielded a correct value for the stoichiometry of interaction. The same method was successfully applied to an investigation of the dissociation kinetics of the [14C]AcNHEtS-Rif - core-polymerase complex.

VD hotline: an evaluation.

A VD hotline started in January 1973 at Monmouth Medical Center, Long Branch, N.J., was evaluated with the following results.

The modification of DNA-dependent RNA polymerase from Escherichia coli by an alkylating derivative of rifamycin SV.

3-(2-Bromo[1-14C]acetamidoethyl)-thio-rifamycin SV, abbreviated BrAcNEtS-Rif, and alkylating derivative of rifamycin SV was synthesized. A four-fold excess of BrAcNEtS-Rif inhibited the enzymic activity of RNA polymerase from Escherichia coli to 97%. Incubation of RNA polymerase with Br[14C]AcNEtS-Rif led to covalent substitution.