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D M Dunn

Publications and source records attributed to D M Dunn.

36 records · Page 2Linked to original sources
PubMed1993

Developing the clinical skills of nurses working in the field of AIDS palliative care.

The study reported here investigated the value of the Self Assessment, Identification of Need and Teaching (SAINT) system in assessing and teaching qualified nurses at work in the field of AIDS palliative care. Primary and community nurses were asked to use the SAINT system to make an assessment of their own nursing skills, identify learning needs and the teaching which they felt was required. Each wrote down their own findings and presented them individually to the researcher; one at a time and, within a group. Under both conditions these nurses were able to assess their skills, identify their needs and suggest teaching. Identification of needs and teaching were found to be more readily available when findings were presented to a group.

Acquired Immunodeficiency Syndrome↗
PubMed1990

A nascent peptide is required for ribosomal bypass of the coding gap in bacteriophage T4 gene 60.

Bacteriophage T4 DNA topoisomerase gene 60 contains a 50 nucleotide untranslated region within the coding sequence of its mRNA. Translational bypass of this sequence by elongating ribosomes has been postulated for the mode of synthesis of an 18 kd polypeptide specified by the split coding segments. Ribosome bypass of the untranslated region also occurs when a segment of gene 60 is fused to lacZ and expressed in E. coli. The efficiency of bypass in these gene 60-lacZ fusions approaches 100%. Here, mutations that delete, insert, or substitute nucleotides from gene 60-lacZ fusions are examined. Essential features necessary for high level gap bypass emerging from this analysis are a cis-acting nascent peptide sequence, a short duplication bordering the gap, and a stop codon contained in a stem-loop structure at the 5' junction of the gap.

Amino Acid Sequence↗
PubMed1990

Prophylactic pinning in slipped upper femoral epiphysis. Prevention of complications.

We report the complications of prophylactic pinning of slipped upper femoral epiphysis with Crawford Adams pins in 95 cases. Complications of pin placement were seen in 13.7%. Although seven hips had penetration of the joint, there were no cases of chondrolysis or avascular necrosis. Excavation of the lateral femoral cortex was required at pin removal in 12.5% of cases. Analysis of the growth around pins allowed recommendations to be made regarding pin protrusion. The use of improved fixation devices may reduce the need for multiple pins.

Adolescent↗
PubMed1989

E. coli ribosomes re-phase on retroviral frameshift signals at rates ranging from 2 to 50 percent.

Many retroviruses express gag-pol or gag-pro-pol polypeptides by coupling their translation from overlapping reading frames with -1 ribosomal frameshifts. Here, we show that the well-known ribosomal frameshift signals found in retroviral mRNA will provoke Escherichia coli ribosomes to shift frame in the same manner as their eukaryotic counterparts. Ribosomes of E. coli respond in vivo to both the tandem slippery codons present at the retroviral frameshift site and the 3' flanking sequence. Slight alteration of the mouse mammary tumor virus gag-pro frameshift site from A-AAA-AAC to A-AAA-AAG boosts the level of frameshifting in E. coli to over 50%. This suggests that A-AAA-AAG, and its slippery relatives, may be utilized by E. coli genes as sites of high-level ribosomal frameshifting. This observed conservation of response to retroviral frameshift signals affords new avenues to dissect the mechanism of ribosomal frameshifting evoked by these mRNA sequences.

Base Sequence↗
PubMed1988

Reading frame switch caused by base-pair formation between the 3' end of 16S rRNA and the mRNA during elongation of protein synthesis in Escherichia coli.

Watson-Crick base pairing is shown to occur between the mRNA and nucleotides near the 3' end of 16S rRNA during the elongation phase of protein synthesis in Escherichia coli. This base-pairing is similar to the mRNA-rRNA interaction formed during initiation of protein synthesis between the Shine and Dalgarno (S-D) nucleotides of ribosome binding sites and their complements in the 1540-1535 region of 16S rRNA. mRNA-rRNA hybrid formation during elongation had been postulated to explain the dependence of an efficient ribosomal frameshift on S-D nucleotides precisely spaced 5' on the mRNA from the frameshift site. Here we show that disruption of the postulated base pairs by single nucleotide substitutions, either in the S-D sequence required for shifting or in nucleotide 1538 of 16S rRNA, decrease the amount of shifting, and that this defect is corrected by restoring complementary base pairing. This result implies that the 3' end of 16S rRNA scans the mRNA very close to the decoding sites during elongation.

Bacterial Proteins↗
PubMed1988

Open reduction of the severely slipped upper femoral epiphysis.

The results of open reduction of the severely slipped upper femoral epiphysis are reported for 115 hips with an average follow-up of 12 years 11 months (range 2 to 33 years). In 70 hips with a chronic slip and an open growth plate the incidence of complications was low: two developed avascular necrosis, five chondrolysis, and one had both. There were more complications in the 38 hips with an acute-on-chronic slip: six developed avascular necrosis, one chondrolysis, and three had both. Of the seven hips operated upon with a partially fused plate, only one did well. All these complications were obvious within the first year but there were also three hips in the series in which osteoarthritis developed between 10 and 20 years after operation.

Adolescent↗
PubMed1985

Serum antielastase and neutrophil elastase levels in PiM phenotype cigarette smokers with airflow obstruction.

In order to assess blood factors which might explain why some cigarette smokers develop airflow obstruction while others do not, we compared two groups of PiM phenotype volunteers matched for age, sex and total pack-years of cigarette smoking; one group had airflow obstruction and the other did not. Functional levels of alpha-2-macroglobulin (alpha-2-M) and alpha-1-protease inhibitor (alpha-1-PI) were separately assessed by a protease binding procedure. Neutrophils were isolated from blood by counterflow centrifugation, and their elastase content was assayed with 3H-elastin-SDS (sodium dodecyl sulfate). The obstructed and nonobstructed groups were not different with respect to functional or immunoreactive levels of alpha-1-PI and alpha-2-M or elastase levels in their neutrophils. We do not find imbalances of circulating elastase or antielastase levels in PiM phenotype smokers with airflow obstruction.

Adult↗
PubMed1982

Effects of ascorbate on insoluble elastin accumulation and cross-link formation in rabbit pulmonary artery smooth muscle cultures.

Cultured pulmonary artery smooth muscle cells derived from the medial vessel layer of weanling rabbits were grown in the presence or absence of sodium ascorbate. The connective tissue elements insoluble elastin and collagen were identified and quantified. Formation and accumulation of alpha-aminoadipic acid gamma-semialdehyde (allysine) and the intermolecular cross-links desmosine (Des), isodesmosine (Ides), and aldol condensation product (Aldol) were evaluated from [14C]lysine pulse-chase experiments. [14C]Des, [14C]Ides, peptide-bound [14C]lysine, [14C]allysine, and [14C]Aldol were determined from amino acid analysis. The latter two components were determined after reduction with NaBH4. [14C]Proline conversion to hydroxy[14C]proline and collagenase susceptibility were used to identify and quantify collagen synthesis. Ascorbate dramatically affects insoluble elastin synthesis, accumulation, and cross-link formation. Cells grown in the presence of ascorbate synthesize and accumulate significantly less insoluble elastin than non-ascorbate cultures. Those elastin molecules which do become incorporated into the extracellular matrix in the presence of ascorbate contain a slightly elevated content of hydroxyproline and lysine and, most importantly, are turned over more rapidly.

Animals↗
PubMed1981

Interactions of mothers with their newborns in the first half-hour of life.

Eight first-time and eight second-time working class mothers were observed interacting with their newborn babies during the first half-hour of life. In all cases the father was present for at least some of this period. The interactions were notable for their passivity, mothers looked for long periods at their babies and engaged in some finger-tip touching of the babies face and head, but they engaged in very little exploration of the babies, few vocalizations and few expressive acts such as kissing. However, the presence of the father was associated with more intense mother-newborn interaction. First-time but not second-time fathers tended to be excluded from interaction with either the mother or the baby at this time. These results are discussed in the light of current thinking on mother-newborn bonding and the role of midwifery staff in promoting that bonding process.

Fathers↗
PubMed1981

Late diagnosis of congenital dislocation of the hip.

A cohort of children presenting with clicking hips was studied in two districts. In one district any child with a clicking hip was treated as though the hip was dislocated, i.e. by splintage in abduction, but in the other district no treatment was offered. None of the 'treated' group later presented with a dislocated hip, whereas four children were found with dislocated hips among the 'untreated' group. A further four children who were not treated because their hips appeared to be normal on the second examination later presented with dislocated hips. It is suggested that the accuracy of diagnosis in all units might be improved if the examination of the newborn was carried out by a limited number of doctors to whom greater experience would accrue. Further improvements would be made if any hip which was found to click on examination was treated as an unstable hip and splinted in abduction.

Child, Preschool↗
PubMed1978

Replacement of the femoral head by open operation in severe adolescent slipping of the upper femoral epiphysis.

The stages in adolescent slipping of the upper femoral epiphysis are classified in relation to treatment. The operation of open replacement of the displaced femoral head is described, and the results of a personal series of seventy-three such operations are presented. Open replacement is excellent treatment for severe chronic slipping so long as the growth plate is still open. The greater incidence of avascular necrosis in acute-on-chronic cases is probably due to damage to the blood supply of the head at the time of the acute slip or kinking of the vessels before replacement. Prolonged traction before operation may increase the risk of chondrolysis. Late onset of osteoarthritis when neither avascular necrosis nor chondrolysis has occurred may be due to misfitting of the articular cartilage because of inaccurate reduction.

Adolescent↗
PubMed1975

Born unto trouble.

We describe unexpected adverse psychological and social results in three adult men with severe Little's disease who were made more mobile by successful surgery.

Adolescent↗