Search PubMedSearch

Biomedical subjects

R Owen

Publications and source records attributed to R Owen.

13 recordsLinked to original sources

Magnetic resonance angiography of the pelvis and lower extremities. Works in progress.

Two-dimensional time-of-flight (TOF) magnetic resonance angiography (MRA) of the lower extremities has recently been rediscovered as a technique that can be used to find small vessels in the foot and leg for surgical revascularization in patients with severe peripheral vascular disease. The purpose of this article is to acquaint the reader with some of the common problems that may be encountered in this imaging technique and to show their derivations and solutions were applicable. In addition, the authors show receiver operator curve analysis of one radiologist's ability to determine the location and patency of arteries using this technique to be outstanding (AZ, 0.9737). This represents a promising new technique for imaging the arterial system in patients with severe peripheral vascular disease.

Blood Vessels

Typing of methicillin resistant and susceptible Staphylococcus aureus strains by ribosomal RNA gene restriction patterns using a biotinylated probe.

Nine methicillin-sensitive (MSSA) and 37 methicillin-resistant (MRSA) Staphylococcus aureus isolates of various phage types and resistotypes from seven countries were investigated. Chromosomal DNA was restricted with HindIII or EcoRI, Southern blotted and hybridised with a cDNA probe to 16S+23S rRNA derived from MRSA NCTC 10442. Resulting rDNA profiles could be differentiated on the basis of 22 patterns which were unaffected by changes in plasmid, transposon, enterotoxin A or phage content. Percentage similarity values were calculated using the Dice coefficient and UPGA clustering. Australian and epidemic (EMRSA-1) isolates from the UK showed a high degree of similarity, but the pattern was not unique and was also found in MSSA and other MRSA, e.g. NCTC 10442. An MSSA of phage group II was the most distinct isolate. The method shows potential as an additional tool in a complex typing system, types non-phage typable strains and may provide clues to the clonal evolution of MRSA and MSSA.

Bacterial Typing Techniques

Amniotic fluid embolism. A report of three cases.

Three patients showing the typical features of amniotic fluid embolism are described. Two survived the insult, while in the third the diagnosis was confirmed by post-mortem histological examination of the lungs.

Adult

Congenital sacral anomalies.

A review of seventy-one children with sacral anomalies is presented. The aetiology is discussed and a classification of sacral anomalies is suggested, with three groups of patients: agenetic, dysgenetic and dysraphic. The clinical presentation of each group is discussed and the high incidence of congenital visceral and skeletal abnormalities is indicated in the dysgenetic group. The need for constant urological assessment is emphasised, particularly in the agenetic and dysraphic children.

Abnormalities, Multiple

Studies on experimental enteric salmonellosis in ponies.

Clinical, bacteriological, serological and haematological observations were made on 13 adult ponies orally inoculated with Salmonella typhimurium. The results were compared to two control ponies and four others infected by accidental transmission. The clinical responses in inoculated ponies included pyrexia lasting four days and neutropaenia during the first five days after inoculation followed by a neutrophilia. Pyrexia and neutropaenia was associated with maximal shedding of organisms in the rectal faeces. Changes in the character of the faeces occurred between one and two days after inoculation and appeared to be associated with the serological response. Serological responses occurred in all the infected ponies except one. At necropsy, of the 14 ponies with positive cultures in the colon, seven had negative cultures in the rectal faeces. Serological studies performed on 43 clinically normal horses indicated a correlation between age and salmonella agglutination titre.

Animals

Repair of fractured dens of the axis in a foal.

Quadriplegia of 4 days' duration in a 3-week-old foal was caused by displacement of the dens of the axis due to a fracture at the dens growth plate. The displacement was reduced and was immobilized surgically. Two months after surgery, the foal was able to rise, walk, and trot without apparent neurologic deficiencies. Three years later, the only defect was a mild gait disturbance in the left hindlimb seen at a canter and a gallop.

Animals

Hair sampling for chromium content following Charnley hip arthroplasty.

The chromium content of hair has been studied by neutron activation analysis of samples from 62 patients following a Charnley unilateral or bilateral hip arthroplasty by an artificial joint of stainless steel against polyethylene, inserted three to five years previously. The patients lived in the North Wales area of the British Isles. Hair chromium content was also studied in 51 control subjects of similar age to that of the patients, from the same geographical area and often from the patients' own households. Chromium content was recorded as parts per million (ppm) of hair weighed and analyzed in the state received, without preliminary ashing or chemical "washing" of the samples in the laboratory. Fifty of the 51 control subjects showed less than 2 ppm chromium in hair; one showed 2-5 ppm; none showed more than 5 ppm. Fifty-nine of the 62 patients showed less than 2 ppm chromium in hair; three showed 2-5 ppm; none showed more than 5 ppm. Attention is drawn to certain practical aspects when collecting hair samples for chromium analysis. The use and validity of hair sampling as one method of screening for systemic chromium accumulation following implant surgery is discussed. The method may be a useful adjunct to monitoring of chromium levels in blood samples. In this preliminary study, hair sampling has given no evidence of any major risk of systemic chromium accumulation in patients using a Charnley arthroplasty for periods of up to five years; no conclusion can be made concerning periods longer than this. The findings do not exclude systemic reactions of the hypersensitivity type, since this type of reaction could develop to only small amounts of chromium.

Acetabulum

Reflections upon the aetiology of congenital pseudarthrosis of the clavicle. With a note on cranio-cleido dysostosis.

The cause of pseudarthrosis of the clavicle is obscure. Right-sidedness is an almost constant feature. We have proposed that the lesion is sometimes due to pressure upon the developing clavicle by the subclavian artery which is normally at a higher level on the right side. This may be accentuated in the presence of cervical ribs or unduly elevated first ribs, both of which we have observed in association with pseudarthrosis. We have also noted pseudarthrosis on the left side in association with dextrocardia (when the relative positions of the subclavian arteries are reversed) and in the presence of a large left cervical rib. We have speculated upon the nature of the clavicular defect in cranio-cleido dysostosis, in which disorder the first ribs are habitually elevated. A similar mechanism may be involved.

Bone Diseases, Developmental