Antibody to B. subtilis DNA polymerase III: use in enzyme purification and examination of homology among replication-specific DNA polymerases.

Bacillus subtilis DNA polymerase III (pol III), an arylhydrazinopyrimidine-sensitive, replication-specific enzyme, was used to generate a non-precipitating rabbit antibody which specifically inhibited pol III activity in vitro. The antibody was used to examine structural relationships among several DNA polymerases, and it was linked covalently to agarose; the antibody:agarose was employed to develop a rapid, selective method of purification of catalytically active B. subtilis pol III.     

Construction of an M13 histidine-transducing phage: a single-stranded cloning vehicle with one EcoRI site.

In order to create a ready source of single-stranded DNA for DNA sequence determination by the dideoxy chain-termination method, the promoter-proximal part of the histidine operon, the hisOGD region of Salmonella typhimurium, was cloned onto the single-stranded phage M13. Both orientations of the his DNA were cloned to supply DNA template for sequencing of each strand. Insertion was achieved at an HaeIII site in the intergenic region (IR) of M13, and a single EcoRI site was purposely regenerated at one boundary of the his DNA insert. Infected colonies, not plaques, were selected using the hisD gene as a selective marker. The single RI site and the hisD marker for auxotrophic selection represent improvements on the wild type M13 as a single-stranded vector for cloning other DNA.     

Value of 1-alpha-hydroxy vitamin D3 in treatment of primary hyperparathyroidism before parathyroidectomy.

The postoperative course of six patients with primary hyperparathyroidism and obvious radiological evidence of bone disease pretreated with 1-alpha-hydroxy vitamin D3 (1 alpha HCC) was indistinguishable from that of six patients with a similar clinical and radiological picture who were not pretreated. 1alphaHCC may increase the hypercalcaemia in some cases and cannot be recommended for the routine preparation of such patients for surgery.     

Quantum yield and image contrast of bacteriochlorophyll monolayers in photoelectron microscopy.

The photoelectron quantum yield spectrum of bacteriochlorophyll aGg (Bchl a ) from Rhodospirillum rubrum was determined in order to evaluate the possibility of mapping photoreceptor distribution and organization in bacterial chromatophores. The quantum yield is on the order of 1 X 10(-3) electrons/incident photon at 180 nm and decreases to 2.5 X 10(-5) electrons/incident photon at 230 nm. Photoelectron micrographs confirm the high contrast predicted between monolayers of Bchl a against a lipid background (calcium arachidate). A significant contrast difference is found between the two monolayer orientations, demonstrating that photoelectron microscopy is a sensitive detector of asymmetry in Bch1 a monolayers.     

The distribution of satellite and main-band DNA components in the melanogaster species subgroup of Drosophila

Fractionation of total adult DNA of five of the seven species of the melanogaster species sub-group of Drosophila in actinomycin D and distamycin A caesium density gradients has revealed the presence of three main-band DNA components, common to all species, and ten satellite DNAs that are distributed between the species. Satellite DNAs are either unique to a species or common to two or more species. The abundance of a common satellite DNA varies between species. There is no simple relationship between the presence of a satellite DNA and a branch point of phylogenetic divergence; nevertheless the arrangement of the species in a phylogeny that is based on the numbers of satellites held in common accurately reflects the pattern of relationships between the same species based on differences in inversions of polytene chromosomes. The species can be similarly arranged according to the compositions of their mitochondrial DNAs. It is possible that the same basic set of sequences, each of low frequency, is common to all species with arbitrary or selected amplification of particular sequences to differing extents in individual species. The conservation of satellites in the group and the close parallel between the distributions of satellites and inversions between the species suggests that either the processes that operate to change both chromosomal phenomena are similarly time-dependent and occurring at relatively low rates or that their rates of change are restricted according to some undetermined functions of these aspects of the genome.     

Nurse specialist in family planning.

In an experimental clinic, run by nurse specialists in family planning, a total of 768 patients were seen in the first year. Oral contraception was dispensed for 377 patients and 187 intrauterine devices (IUCDs) were inserted; a further 204 IUCD patients attended only for follow-up visits. All side effects were adequately diagnosed by the nurse specialist.     

Transplantation of tumour with a kidney graft.

A cerebral glioma discovered by angiography and brain biopsy in a kidney donor was subsequently suspected of being a secondary tumour. By this time a biopsy of one of the transplanted kidneys had shown a clump of malignant cells in a glomerulus. Because of the psychological state of this recipient the transplant was not removed, but the recipient of the second kidney was immediately told of the danger of tumour cell transfer, and underwent nephrectomy. The patient remained well on haemodialysis; multiple sectioning of the kidney showed no signs of tumour. The transplant in the first recipient functioned well until his death, six months after operation. At necropsy undifferentiated tumour was found in the pleura, liver, pelvic peritoneum, and transplanted kidney. All cadaver donors should undergo full laparotomy after removal of the kidneys, particularly those with a high risk of cancer, and a full necropsy should also be performed shortly afterwards to exclude tumour and other unsuspected diseases. Then it is not too late to remove a transplanted kidney should a tumour be found.     

An apparatus for anesthetizing small laboratory animals.

A simple apparatus was designed for simultaneous general anesthesia of a number of small laboratory animals with spontaneous respiration. Anesthesia is consistent over many hr. The apparatus consists of an oxygen tank and vaporizer, a glass distribution bottle, and a non-return circuit of separate inspiratory and expiratory valves for each animal. The equipment is inexpensive to construct and can be rapidly adjusted for exact control of gas flow and anesthetic depth.