Biomedical subjects

D Jones

Publications and source records attributed to D Jones.

At least 577 records · Page 32Linked to original sources

PubMed1989

Closure of chronic postpneumonectomy bronchopleural fistula using the transsternal transpericardial approach.

Thirteen patients with postpneumonectomy bronchopleural fistula occurring 4 months to 10 years after the initial operation have been treated with a transsternal transpericardial approach after the associated empyema had been treated by either tube thoracostomy or open-window thoracostomy. In 10 patients, there were contraindications to using an ipsilateral transthoracic approach. In 10 of the 13 patients, the procedure was successful. Three fistulas recurred; two were quite small, one of them closing spontaneously within 6 months. There were no deaths or clinically significant morbidity related to the transsternal approach. We have found this technique to be most applicable in those patients in whom other procedures have failed to resolve the problem. The technique is relatively simple and safe.

Adult↗

PubMed1989

Design guidelines for speech recognition interfaces.

Seven classes of design guidelines are described for interfaces which use speech recognition. The guidelines concern: (i) allocation of function within complex systems; (ii) parallel processing of speech with other modalities; (iii) design of command vocabulary; (iv) choice of command syntax; (v) use of feedback; (vi) template and user training; and (vii) choice of evaluation criteria.

Journal Article↗

PubMed1989

Comparative studies on the protein composition of hymenopteran venom reservoirs.

The proteins of venom reservoirs from 25 hymenopteran species from 21 genera were investigated with regard to their protein composition and immunological similarities. It was found that low mol. wt proteins and polypeptides are typical for the venoms of ants, social wasps and bees. Six species of ichneumonoid parasitic wasps lack these low mol. wt proteins. Except for bee venoms none of the low mol. wt proteins contain mannose. The venoms of ichneumonoid parasites and ants contained primarily acidic proteins, whereas those of social wasps and bees contained abundant neutral and basic proteins. Immunological analysis showed that a number of venom proteins from parasitic braconid (Chelonus) wasps shared conserved immunoreactive determinants with the venom proteins of higher Hymenoptera, including some not of parasitic habit. Implications of phylogenetic relationships among hymenopteran species are discussed.

Animals↗

PubMed1989

The recording of morbidity related to radiotherapy.

Radiation morbidity is as important as tumour control when determining the value of radiotherapy, but there is no internationally agreed system for the recording of morbidity. A scheme based upon the scoring of the elements which make up morbidity has been endorsed by a 2-day Workshop sponsored by the Medical Research Council and a system is now available for trial.

Digestive System↗

PubMed1989

A port film marker.

A device is described consisting of brass strips embedded in a plastic plate. When inserted in a radiation beam, it produces an image of a cross centered in the field. Cuts in the brass at defined intervals project a scale on the film used to determine a magnification factor. A marker in the lower right-hand quadrant provides rapid, unequivocal orientation of the film. This capability of orientation to a beam's-eye-view makes anatomical markers redundant.

Equipment Design↗

PubMed1989

A non-contacting intraoperative electron cone apparatus.

Aluminum tubes, 20 cm long, of various diameter and face angle have been used to collimate electron beams for intraoperative radiotherapy. The tubes placed in a body cavity are clamped to the treatment couch. A thin rod is fixed coaxially to a disc which is placed on the entrance face of the tube. A stepwise procedure involving couch translation, rotation, and gantry rotation is used to align the central axis of the beam with the axis of the cone. Further collimation is provided by an aperture mounted in an assembly which slides into the standard accessory holder of the machine and is separated by a 10 cm air gap from the tube in the patient. Careful adjustment of this aperture diameter results in a relatively uniform dose across the treated area. The use of 3 mm wall thickness aluminum tube provides for minimal leakage outside of the cone. A camera has been mounted to a plate that also mounts in the standard accessory holder and is used to document the area treated.

Electrons↗

PubMed1989

Differential regulation of closely related members of the hsp16 gene family in Caenorhabditis elegans.

The heat-inducible genes encoding 16-kD heat shock polypeptides in Caenorhabditis elegans are found at two separate loci, one containing the 16-1 and 16-48 genes (locus A), and the other, the 16-2 and 16-41 genes (locus B). Despite the highly conserved structures of these genes and their promoters, the B locus produces up to sevenfold more mRNA during heat induction than does the A locus. Since there are two copies of the 16-1 and 16-48 genes at the A locus, the discrepancy in mRNA production is actually as high as 14:1 on a per gene basis. Measurements of the rate of hsp16 mRNA decay during recovery from a heat shock suggest that this difference is not caused by differential mRNA stability; furthermore, nuclear runon experiments yield rates of transcription for the 16-1/48 locus that are approximately threefold higher than those from the 16-2/41 locus. The higher levels of mRNA from the 16-2/41 locus, particularly at longer induction times, seem to be due to a marked difference in the temporal pattern of mRNA production from the two loci. While both loci are transiently activated by a heat shock, the 16-1 and 16-48 genes of the A locus are down-regulated to a lower transcription rate sooner than the genes from the B locus.

Animals↗

PubMed1989

Blood group, secretor status and susceptibility to bacterial meningitis.

Epidemiological evidence is summarized for associations of ABO blood group and secretor status with susceptibility to invasive disease due to capsulate organisms responsible for the majority of bacterial meningitis. Host-parasite interactions that might underly these findings are proposed and evidence to support or refute them provided.

Bacterial Infections↗

PubMed1989

Comparison of in situ hybridization and monoclonal antibodies for early detection of cytomegalovirus in cell culture.

The abilities of each of four diagnostic tests--direct fluorescent monoclonal antibody (direct FA) staining, indirect fluorescent monoclonal antibody (indirect FA) staining, in situ hybridization with biotinylated DNA probes, and in situ hybridization with DNA probes directly linked to enzymatically active horseradish peroxidase-to detect cytomegalovirus soon after culture were compared. Only the indirect FA test and the in situ hybridization method with directly linked HRP-DNA probes provided consistent and reliable cytomegalovirus detection as early as 15 h postinfection.

Antibodies, Monoclonal↗

PubMed1989

UbiA, the major polyubiquitin locus in Caenorhabditis elegans, has unusual structural features and is constitutively expressed.

Ubiquitin is a multifunctional 76-amino-acid protein which plays critical roles in many aspects of cellular metabolism. In Caenorhabditis elegans, the major source of ubiquitin RNA is the polyubiquitin locus, UbiA. UbiA is transcribed as a polycistronic mRNA which contains 11 tandem repeats of ubiquitin sequence and possesses a 2-amino-acid carboxy-terminal extension on the final repeat. The UbiA locus possesses several unusual features not seen in the ubiquitin genes of other organisms studied to date. Mature UbiA mRNA acquires a 22-nucleotide leader sequence via a trans-splicing reaction involving a 100-nucleotide splice leader RNA derived from a different chromosome. UbiA is also unique among known polyubiquitin genes in containing four cis-spliced introns within its coding sequence. Thus, UbiA is one of a small class of genes found in higher eucaryotes whose heterogeneous nuclear RNA undergoes both cis and trans splicing. The putative promoter region of UbiA contains a number of potential regulatory elements: (i) a cytosine-rich block, (ii) two sequences resembling the heat shock regulatory element, and (iii) a palindromic sequence with homology to the DNA-binding site of the mammalian steroid hormone receptor. The expression of the UbiA gene has been studied under various heat shock conditions and has been monitored during larval moulting and throughout the major stages of development. These studies indicate that the expression of the UbiA gene is not inducible by acute or chronic heat shock and does not appear to be under nutritional or developmental regulation in C. elegans.

Animals↗

PubMed1989

Structure, organization, and expression of the 16-kDa heat shock gene family of Caenorhabditis elegans.

Exposure of the nematode Caenorhabditis elegans to a heat shock results in the induction of a number of genes not normally expressed in the animals under normal growth conditions. Among these are a family of genes encoding 16 kDa heat shock proteins (hsp16s). The major hsp16 genes have been cloned and characterized, and found to reside at two clusters in the C. elegans genome. One cluster contains two distinct genes, hsp16-1 and hsp16-48, arranged in divergent orientations separated by only 348 base pairs (bp). An identical pair, duplicated and inverted with respect to the first pair, is located 415 bp away. This cluster, located on chromosome V, therefore contains four genes as two identical pairs within less than 4 kilobases of DNA, and the pairs form the arms of a large inverted repeat. A second pair of genes, hsp16-2 and hsp16-41, constitutes a second hsp16 locus with an organization very similar to that of the hsp16-1/48 locus, except that it is not duplicated. Comparisons of the derived amino acid sequences show that hsp16-1 and hsp16-2 form a closely related pair, as do hsp16-41 and hsp16-48. These hsps show extensive sequence identity with the small hsps of Drosophila, as well as with mammalian alpha-crystallins. The coding region of each gene is interrupted by a single intron of approximately 50 bp, in a position homologous to that of the first intron in mouse alpha-crystallin gene.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed1989

The cardiopulmonary and renal hemodynamic effects of norepinephrine in canine pulmonary embolism.

Autologous blood clot was injected into six dogs to produce a graduated decrease in cardiac output (CO). The effects of an infusion of norepinephrine, titrated to specific end points, were recorded before embolization and at two levels of pulmonary hypertension. Simultaneous measurements of systemic and renal hemodynamics were made. Sequential blood clot injection increased (p less than .01) pulmonary vascular resistance (PVR) from 1.3 to 13 to 33 mm Hg.L-1.min and reduced CO 45 percent and 75 percent (p less than .01). Norepinephrine increased both stroke volume and CO (p less than .01) in each condition and did not increase PVR. Since the biventricular filling pressures remained constant or fell slightly with norepinephrine, the increase in CO is best explained by an improvement in pump performance. There was no deterioration in renal blood flow or creatinine clearance with norepinephrine. The data suggested that in this model of right ventricular dysfunction, norepinephrine consistently improved myocardial performance without provoking further vasoconstriction in either the pulmonary or renal circulations.

Animals↗

PubMed1989