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Biomedical subjects

W J Kerr

Publications and source records attributed to W J Kerr.

At least 19 recordsLinked to original sources
PubMed2001

Key tricyclic synthetic intermediates for the preparation of the sesquiterpenes alpha- and beta-cedrene.

A completely novel and direct route towards the synthesis of the natural sesquiterpenes alpha-cedrene and beta-cedrene delivered the compounds (3 beta,3a beta,7 beta)-(+/-)-6,6-ethylenedioxy-3,8,8-trimethyl-2,3,3a,4,5,6,7,8-octahydro-3a,7-methanoazulen-2-one, C(16)H(22)O(3), and (3 beta,3a beta,7 beta,8a alpha)-(+/-)-6,6-ethylenedioxy-3,8,8-trimethyl-1,2,3,3a,4,5,6,7,8,8a-decahydro-3a,7-methanoazulen-2-one, C(16)H(24)O(3), at key stages of the preparative programme. Structural elucidation showed the latter compound to have added an H atom to the same face of the cyclopentenone ring as that occupied by the methyl substituent, and also allowed correct isomer identification for further reaction.

Journal Article↗
PubMed2001

Enantioselective deprotonation reactions using polymer-supported chiral magnesium amide bases.

Novel and readily accessible polymer-supported chiral magnesium amide reagents have been prepared and shown to be effective in the asymmetric deprotonation of a series of prochiral cyclohexanones, affording good to excellent levels of both conversion and enantiomeric ratio (up to 93:7); the Merrifield-based chiral amine species has been shown to be readily recyclable.

Journal Article↗
PubMed2001

Formal total synthesis of (+/-)-alpha- and beta-cedrene by preparation of cedrone. Construction of the tricyclic carbon skeleton by the use of a highly efficient intramolecular Khand annulation.

The cedrene carbon skeleton was rapidly assembled from a simple monocyclic precursor by the strategic use of a high yielding intramolecular Khand cyclization reaction. Further synthetic manipulations provided a concise formal total synthesis of alpha- and beta-cedrene. Reaction: see text.

Heterocyclic Compounds, 3-Ring↗
PubMed2001

Magnesium bisamides as reagents in synthesis.

As part of the continued requirement for more selective reagents in organic synthesis, magnesium bisamides are becoming established as a class of organometallic bases with considerable potential. Their relatively mild reactivity, combined with their high degree of steric congestion, leads to a distinct class of reagents with significantly different chemo-, regio-, stereo- and enantioselectivities when compared with existing species and protocols.

Journal Article↗
PubMed2000

The first orthodontic diploma.

The advent of the Inter-Collegiate Membership in Orthodontics in the year 2000 will mark the end of an orthodontic diploma specific to the Royal College of Physicians and Surgeons of Glasgow. The Diploma in Dental Orthopaedics (RCPS) was the first orthodontic diploma in the United Kingdom. The fact that such a diploma has existed first as a DDO and latterly as the MDO (Membership) for some 50 years is remarkable in view of the relative infancy of most dental specialties and the fact that the General Dental Council has instigated a specialist register in orthodontics as recently as 1998. It was 1965, before other specialty diplomas became available in the British Isles, with the introduction of the FFD by the Royal College of Surgeons in Ireland.

Education, Dental, Graduate↗
PubMed2000

An evaluation of CASES--an educational audit programme for orthodontists.

A regional approach to a national clinical audit programme in orthodontics in the UK is described and evaluated. The programme was designed using the CRISIS criteria for effective continuing education. Programme participants completed duplicate questionnaires on 6 simulated patient scenarios, chosen for their relevance to everyday practice while posing important clinical dilemmas. The participation rate was 77% from hospital-based practitioners and 29% from specialist practitioners. Feedback to programme participants was given in the form of histograms, and provided a snapshot of national approaches to patient investigation, treatment and expected outcomes. A commentary on the data and references to appropriate articles in the literature were included. Evaluation of the programme by questionnaire survey showed that it was extensively used by hospital-based practitioners. It is concluded that the model used provided an effective and efficient framework for conducting clinical audit and delivering continuing education to the hospital-based group.

Adult↗
PubMed2000

Describing shape changes in the human mandible using elliptical Fourier functions.

Elliptical Fourier functions (EFF) were generated for the boundary outline of the mandibular form in 24 non-orthodontic growth study subjects at 9, 11, 13, and 15 years of age. The mean residual fit (observed versus predicted points) of the mandibular form was 0.11 mm, with a range from 0.09 to 0.14 mm, suggesting an accurate fit. The mean plot for each of the four age groups was area standardized and superimposed on the centroid. Shape changes in males and females were found to be similar. No significant shape changes were found between 9 and 11 years. Shape changes were observed in the lower incisor area, the mental region, the body of the mandible, and the gonial angle area between 11 and 15 years. These changes coincided with the onset of the pubertal growth spurt.

Adolescent↗
PubMed2000

Orthodontic treatment with fixed appliances in the General Dental Service in Scotland.

The records of 128 subjects treated by orthodontic specialists with fixed appliances in the General Dental Service in Scotland were randomly selected from the Scottish Dental Practice Board for analysis. The results of the study revealed that: (1) Mean post-treatment Peer Assessment Rating was 7.8 +/- 4.6 PAR points. (2) Mean reduction in PAR score was 14.9 +/- 10.6 PAR points. (3) Mean percentage reduction in PAR was 59 per cent. (4) Twenty-eight per cent of the cases were 'greatly improved', 15 per cent of the cases were made 'worse or no different'. (5) Median duration of treatment was 15 months, with a range of 2-41 months. (6) Multiple regression analysis showed that 82 per cent of the variability of PAR change could be predicted by the pretreatment PAR scores and the number of arches treated. Post-treatment PAR scores and duration of treatment could not be predicted with adequate reliability. It was concluded that although about 75 per cent of the cases were treated to at least acceptable alignment and occlusion, the modest average percentage reduction in PAR score could be explained by the low average initial PAR score and the borderline need for treatment in many cases.

Episode of Care↗
PubMed1998

Soft and hard tissue changes in Class III patients treated by bimaxillary surgery.

A cephalometric study of 17 non-growing dentate Class III subjects treated by bimaxillary surgery was undertaken to assess the results of treatment and to evaluate the correlation between soft and hard tissue change. It was concluded that: (i) the orthognathic profiles achieved were brought about by a combination of maxillary advancement and mandibular setback; (ii) a strong correlation in the horizontal direction occurred between all the selected landmarks of the lower lip and chin, but only between superior labial sulcus and point A in the upper lip; highest intra-group correlations were seen between corresponding soft and hard tissue points; the ratios of soft tissue to corresponding hard tissue movements in lower lip and chin approached 1:1; (iii) in the vertical direction, a strong correlation occurred in the lower lip and chin; highest intra-group correlations were not necessarily with corresponding landmarks; and (iv) vertical movement of landmarks on the nasal base and upper lip generally showed poor or weak correlation with corresponding soft tissue points. The most reliable hard tissue predictors of horizontal and vertical soft tissue change are tabulated for application in bimaxillary surgery for the Class III patient.

Adult↗
PubMed1998

The laryngeal mask as an antipollution device.

Anaesthetic pollution is still a problem and recent UK Control of Substances Hazardous to Health (COSHH) recommendations require employers to attempt to control the risk. Fifteen day-case urology operating lists were studied to compare the level of nitrous oxide exposure using face mask or laryngeal mask anaesthesia. Nitrous oxide was avoided in one group until the laryngeal mask was inserted. The use of the laryngeal mask airway showed a significant reduction in the level of pollution, such that recent COSHH recommendations were attained. However, (US) NIOSH levels were only reliably attained by avoiding nitrous oxide until the laryngeal mask was inserted. The laryngeal mask was therefore shown to be a reliable antipollution device.

Air Pollutants, Occupational↗
PubMed1998

Light-curing acrylic resin as an orthodontic baseplate material.

Heat-curing autopolymerizing (self-cure or cold-cure), thermoplastic, and light-curing acrylic resin are the most commonly used orthodontic baseplate materials. While cured acrylic resins present few problems to the patient, in the laboratory acrylic resin has to be sprayed, mixed, or packed in a fume-extraction unit because of the harmful fumes emitted by the raw inflammable chemicals. Light-curing material, on the other hand, is virtually nonflammable and has virtually no aroma. A light-cure technique for the construction of orthodontic baseplates is described. While buildup of the baseplate is slightly slower than for self-cured material, the shorter time involved in trimming and polishing means that overall construction is faster. It is easier to obtain a uniform thickness with light-cured material, and it provides superior fit. These results, however, are subject to more extensive clinical trials. The only apparent disadvantage is the fine powder produced during trimming. Even with a bench equipped with an extraction unit, it is advisable to use a face mask to prevent the inhalation of dust.

Acrylic Resins↗
PubMed1997

CASES--clinical audit; scenarios for evaluation and study.

CASES, an audit and continuing education programme, evaluated aspects of current orthodontic practice and allowed orthodontists to identify areas where their practice differed from regional and national results. Evaluation of the CASES programme verified its value in audit and continuing education and the authors hope it will encourage similar projects in other disciplines too.

Adolescent↗
PubMed1997

Appliance wear: the patient's point of view.

Fifty-two patients (35 female, 17 male) completed questionnaires related to their experiences during the first 7 days of appliance wear (31 fixed, 21 removable) and then after 14 and 90 days. Most problems relating to discomfort and pain resolved within 4-7 days. The problems encountered with fixed appliances were generally more severe than with removable appliances. Swallowing and speech were more difficult with removable appliances and these problems persisted to some degree. Surprisingly, the embarrassment caused by wearing the appliance in public was similar whether it was fixed or removable.

Adaptation, Physiological↗