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S Vaughan

Publications and source records attributed to S Vaughan.

At least 19 recordsLinked to original sources
PubMed2005

An origin for short gamma-ray bursts unassociated with current star formation.

Two short (< 2 s) gamma-ray bursts (GRBs) have recently been localized and fading afterglow counterparts detected. The combination of these two results left unclear the nature of the host galaxies of the bursts, because one was a star-forming dwarf, while the other was probably an elliptical galaxy. Here we report the X-ray localization of a short burst (GRB 050724) with unusual gamma-ray and X-ray properties. The X-ray afterglow lies off the centre of an elliptical galaxy at a redshift of z = 0.258 (ref. 5), coincident with the position determined by ground-based optical and radio observations. The low level of star formation typical for elliptical galaxies makes it unlikely that the burst originated in a supernova explosion. A supernova origin was also ruled out for GRB 050709 (refs 3, 31), even though that burst took place in a galaxy with current star formation. The isotropic energy for the short bursts is 2-3 orders of magnitude lower than that for the long bursts. Our results therefore suggest that an alternative source of bursts--the coalescence of binary systems of neutron stars or a neutron star-black hole pair--are the progenitors of short bursts.

Journal Article↗
PubMed2002

Practical lessons from the management of an outbreak of small round structured virus (Norwalk-like virus) gastroenteritis.

An outbreak of viral gastroenteritis caused illness in 92 people during October 2000. All the cases had an association with one hotel and 80% of cases identified had attended one of two buffet meals on 18th October 2000. Cohort analysis did not implicate any particular foodstuff in this outbreak. All bacteriological tests on food samples were negative. Small round structured virus (SRSV)/Norwalk-like virus (NLV) particles were seen by electron microscopy in 6 out of 27 stool samples submitted for analysis. This paper describes the outbreak and in particular the lessons learned from the management and control of it. These include practical points with regard to the outbreak control team, liaison with the microbiology laboratory, handling data, agreeing a case definition, and occupational health issues. All can be applied elsewhere by those responsible for managing outbreaks at a local level.

Caliciviridae Infections↗
PubMed2001

Assessing the subjective experience of being a participant in psychiatric research.

OBJECTIVE: To address both clinical and ethical concerns in psychiatric research, the study assessed the subjective experience of being a participant in a feasibility study of outcome in long-term psychodynamic psychotherapy and psychoanalysis. METHOD: A questionnaire assessing positive and negative reactions to three typical research methodologies (self-report questionnaires, structured diagnostic interviews, and tape-recording of sessions) was administered to 23 patient-therapist pairs. RESULTS: Patients reported that questionnaires and interviews were slightly to moderately helpful in promoting self-realization and facilitating therapy, and not at all to slightly intrusive and disruptive. Adjustment to audiotaping of sessions was rapid (within two sessions). Therapists significantly overestimated the negative effects and underestimated the positive benefit patients reported from participating in research. CONCLUSIONS: Traditional objections to research in dynamic psychotherapy on the grounds that patients experience research procedures as significantly intrusive and disruptive appear to be unfounded.

Adult↗
PubMed2001

The extended tubulin superfamily.

Although most eukaryotic cells can express multiple isotypes of alphabeta-tubulin, the significance of this diversity has not always been apparent. Recent data indicate that particular alphabeta-tubulin isotypes, both genome encoded and those derived by post-translational modification, can directly influence microtubule structure and function--thus validating ideas originally proposed in the multitubulin hypothesis over 25 years ago. It has also become increasingly evident over the past year that some (but intriguingly not all) eukaryotes encode several other tubulin proteins, and to date five further members of the tubulin superfamily, gamma, delta, epsilon, zeta and eta, have been identified. Although the role of gamma-tubulin in the nucleation of microtubule assembly is now well established, far less is known about the functions of delta-, epsilon-, zeta- and eta-tubulin. Recent work has expanded our knowledge of the functions and localisation of these newer members of the tubulin superfamily, and the emerging data suggesting a restricted evolutionary distribution of these 'new' tubulin proteins, conforms to established knowledge of microtubule cell biology. On the basis of current evidence, we predict that delta-, epsilon-, zeta- and eta-tubulin all have functions associated with the centriole or basal body of eukaryotic cells and organisms.

Amino Acid Sequence↗
PubMed2000

Determination of stable isotopic enrichment and concentration of glycerol in plasma via gas chromatography-mass spectrometry for the estimation of lipolysis in vivo.

Measuring glycerol's rate of appearance into the plasma compartment provides an excellent estimation of whole-body lipolysis. The glycerol rate of appearance can be calculated by estimating the plasma dilution of continuously infused stable or radioactive isotopes of glycerol. Previously, determination of glycerol stable isotopic enrichment has required either chemical ionization gas chromatography-mass spectrometry (GC-MS) or electron impact ionization GC-MS in which a fragment containing only a portion of the glycerol molecule was measured. The present method uses tert.-butyldimethylsilyl (tBDMS) derivatization and electron impact ionization to measure a fragment including the entire glycerol molecule. The method determines concentration and enrichment of plasma glycerol in a simple, precise, and cost-efficient manner, providing a basis from which lipid homeostasis can be assessed.

Animals↗
PubMed2000

Tooth wear treated with direct composite restorations at an increased vertical dimension: results at 30 months.

STATEMENT OF PROBLEM: Severe tooth wear localized to the anterior maxillary or mandibular teeth with loss of interocclusal space is difficult to manage. PURPOSE: This study evaluated the outcome of composite restorations placed at an increased vertical dimension of occlusion in such patients. METHODS AND MATERIAL: Sixteen patients were restored with 104 restorations in 2 groups. In group A, Durafill composite and Scotchbond Multipurpose dentine adhesive system were used to place direct anterior restorations (N = 52). In group B, Herculite XRV composite and Optibond dentine bonding agent was used (N = 52). The restorations were placed at an increased vertical dimension of occlusion creating a posterior disclusion of 1 to 4 mm. RESULTS: Clinical follow-up showed that the posterior occlusion remained satisfactorily restored after a mean duration of 4.6 months (range 1 to 11 months). Mean follow-up of 30 months has shown a combined success rate of 89.4% for both groups with 93 of the restorations remaining in service. Maintenance in group A was high with 33 failures, but low in group B with 6 failures. Patient satisfaction was reported as good. CONCLUSION: Direct composite restorations may be a treatment option for localized anterior tooth wear.

Adult↗
PubMed2000

The provision of occlusal splints in primary dental care.

UNLABELLED: Occlusal splints (Michigan splints, night/bite guards or bite-raising appliances) can be an effective, inexpensive and reversible treatment for a wide range of dental problems. OBJECTIVE: The aim of this study was to analyse retrospectively the provision of occlusal splint ('Michigan' type) in general dental practice, following a prescription by a restorative dental consultant. METHOD: One hundred patients were recruited from consultant clinics in a department of conservative dentistry during 1995 and 1996. All patients were prescribed a maxillary, full-coverage, heat-cured, acrylic-resin splint (Michigan splint) as part of a treatment plan. An explanatory letter and questionnaire were sent to all patients and to their referring general dental practitioner in 1997 and 1998. RESULTS: A response rate of 79% was achieved in obtaining completed questionnaires from both patients and general dental practitioners. Of respondents 43% (34/79) received an occlusal splint of some form. A small proportion of the respondents (16.5% [13/79]) received a Michigan splint as prescribed. Irrespective of the type of appliance provided, most patients (82% [28/34]) found them helpful. Of those who did not receive an occlusal splint, 38% (17/45) of patients felt financial implications deterred them from obtaining an appliance. Other common reasons for non-provision included: patients felt that symptoms had improved (18% [8/45]) and patients did not agree with treatment (18% [8/45]). The general dental practitioners had similar opinions to their patients. DISCUSSION: These findings raise some serious doubts on the efficacy of consultant clinic advice in the prescription of occlusal splints in general dental practice. The financial and educational issues raised by this study will need to be addressed to improve service provision. CONCLUSION: The results of this study indicate that 16.5% of patient respondents prescribed a Michigan splint at a consultant clinic received such an appliance in general dental practice.

Comprehensive Dental Care↗
PubMed1998

Postoperative adjuvant radiotherapy and 5-fluorouracil chemotherapy for rectal carcinoma.

Postoperative combined modality therapy with radiotherapy and 5-fluorouracil (5FU) chemotherapy is an effective adjuvant approach that reduces locoregional and distant metastatic disease in patients with high-risk rectal carcinoma. However, this approach results in a treatment regimen of at least 6 months' duration. The present prospective study investigates the integration of radiotherapy and 5FU chemotherapy in a protocol designed to minimize toxicity and reduce the overall treatment time. A total of 40 patients with TNM stage II or III disease received postoperative radiotherapy at four fractions per week with weekly 5FU bolus injections delivered on the fifth non-radiotherapy day. Patients also received systemic chemotherapy with leucovorin both before and after pelvic irradiation, with the total treatment duration extending for only 18 weeks. Patients were able to complete radiotherapy in 90% of cases, while the delivery of full-dose chemotherapy was achievable in the vast majority. The incidence of haematologic and gastrointestinal toxicities requiring the cessation of treatment was acceptable. With a median follow-up of 20.9 months among surviving patients, the estimated progression-free and overall survival at 2 years were 71% and 79%, respectively.

Adenocarcinoma↗
PubMed1995

The gentle touch.

This research study, which, because of its small numbers should be regarded as more of a pilot study, investigated the effect that therapeutic touch may have on measurable physical signs of the subjects involved. It also looked at any change this complementary therapy may have made in health perception immediately following the experiment and 1 week later. The design is modelled on that of Quinn (1984), eminent researcher in the field of energy exchange. Therapeutic touch is a misnomer because physical touch is not necessary--it is the energy field that is touched.

Adult↗
PubMed1994

Up in smoke?

Explore the source record for details and available documents.

Advertising↗
PubMed1990

Autoreactive platelet antibody in post transfusion purpura.

Post transfusion purpura in a DR3, DRw52 positive, PlA1 negative woman rapidly responded to high-dose intravenous gammaglobulin therapy. Using the platelet immunofluorescence test (PIFT) high titre IgG and IgM alloantibodies were detected in the patient's acute serum. These alloantibodies had PlA1 specificity and the patient's serum produced a broad, 100 kDa band on Western Blot with PlA1 positive platelets. Acute phase serum also contained an IgG antibody which reacted in the PIFT with the patient's own platelets, and PlA1 negative platelets. When tested by Western Blot with PlA1 negative and Glanzmann's Thrombasthenia platelets, the acute serum produced bands at 180 and 200 kDa. The autoreactive antibody was not detected once the platelet count returned to normal. These findings provide evidence for the hypothesis that the mechanism of autologous platelet destruction in PTP is autoimmune.

Autoantibodies↗
PubMed1990

Organizational factors affecting growth and decline in adult day-care programs: a comparative study.

Data derived from a mailed questionnaire of adult day-care providers in Illinois and from the records of the Illinois Department on Aging for fiscal years 1984 and 1985 were analyzed to determine which factors affect growth or decline in the programs, measured in terms of number of clients served and units of service provided. Initial analysis revealed that all providers under contract with the state for less than 3 years were growing, and approximately one half of the older providers had similar changes. A separate regression analysis of the older adult day care providers indicated that growth tended to be positively associated with reports of good relationships with referral agents and resource support from umbrella organizations and the larger community, and negatively associated with longevity of the provider. These findings highlight the importance of supportive interorganizational relationships for program growth.

Adult↗