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J Williams

Publications and source records attributed to J Williams.

At least 37 records · Page 2Linked to original sources
PubMed2006

What are the clinical outcome and cost-effectiveness of endoscopy undertaken by nurses when compared with doctors? A Multi-Institution Nurse Endoscopy Trial (MINuET).

OBJECTIVES: To compare the clinical outcome and cost-effectiveness of doctors and nurses undertaking upper and lower gastrointestinal endoscopy. DESIGN: The study was a pragmatic randomised controlled trial. Zelen's randomisation before consent was used to minimise distortion of existing practice in the participating sites. An economic evaluation was conducted alongside the trial, assessing the relative cost-effectiveness of nurses and doctors. SETTING: The study was undertaken in 23 hospitals in England, Scotland and Wales. In six hospitals nurses undertook both upper and lower gastrointestinal endoscopy, yielding a total of 29 'centres'. The study was coordinated and managed from Swansea. Randomisation, data management and analysis were undertaken at York. Analysis was by intention-to-scope. PARTICIPANTS: Sixty-seven doctors and 30 nurses took part in the study. Of 4964 potentially eligible patients, 4128 (83%) were randomised. Of these, 1888 (45%) were recruited to the study from 29 July 2002 to 30 June 2003. INTERVENTIONS: The procedures under study were diagnostic upper gastrointestinal endoscopy and flexible sigmoidoscopy undertaken by nurses or doctors, with or without sedation, using the preparation, techniques and protocols of participating hospitals. MAIN OUTCOME MEASURES: Primary outcome measure was the Gastrointestinal Symptom Rating Questionnaire (GSRQ). The secondary outcome measures were EuroQol (EQ5D), Gastrointestinal Endoscopy Satisfaction Questionnaire (GESQ), State-Trait Anxiety Inventory (STAI), cost-effectiveness, immediate and delayed complications, quality of examination by blinded assessment of endoscopic video recordings, quality of procedure reports, patients' preferences for operator 1 year after endoscopy, and new diagnoses at 1 year. RESULTS: The two groups were well matched at baseline for demographic and clinical characteristics. Significantly more patients changed from a planned endoscopy by a doctor to a nurse than vice versa, mainly for staffing reasons. There was no significant difference between the two groups in the primary or secondary outcome measures at 1 day, 1 month or 1 year after endoscopy, with the exception of patient satisfaction at 1 day, which favoured nurses. Nurses were significantly more thorough in the examination of stomach and oesophagus, but no different from doctors in the examination of duodenum and colon. There was no significant difference in costs to the NHS or patients, although doctors cost slightly more. Although quality of life measures showed improvement in some scores in the doctor group, this did not reach traditional levels of statistical significance. Even so, the economic evaluation, taking account of uncertainty in both costs and quality of life, suggests that endoscopy by doctors has an 87% chance of being more cost-effective than endoscopy by nurses. CONCLUSIONS: There is no statistically significant difference between doctors and nurses in their clinical effectiveness in diagnostic endoscopy. However, nurses are significantly more thorough in the examination of oesophagus and stomach, and patients are significantly more satisfied after endoscopy by a nurse. Endoscopy by doctors is associated with better outcome at 1 year at higher cost, but overall is likely to be cost-effective. Further research is needed to evaluate the clinical outcome and cost-effectiveness of nurses undertaking a greater role in other settings, to monitor the cost-effectiveness of nurse endoscopists as they become more experienced and to assess, the effect of increasing the number of nurse endoscopists on waiting times for patients, and the career implications and opportunities for nurses who become trained endoscopists. Evaluation of the clinical outcome and cost-effectiveness of diagnostic endoscopy for all current indications is also needed.

Aged↗
PubMed2005

Evidence for Bs* Bs* production at the Gamma(5S) resonance.

We use data collected by the CLEO III detector at the Cornell Electron Storage Ring to measure the inclusive yields of D(s) mesons as B(Y(5S) --> D(s)X) = (44-7 +/- 4.2 +/- 9.9)% and B(Y(4S) --> D(s)X) = (18.1 +/- 0.5 +/- 2.8)%. From these measurements, we make a model dependent estimate of the ratio of B(s)*B(s)* to the total bb quark pair production of (16.0 +/- 2.6 +/- 5.8)% at the Y(5S) energy.

Journal Article↗
PubMed2005

Improved measurement of B(D+ --> mu+nu) and the pseudoscalar decay constant fD+.

We extract a relatively precise value for the decay constant of the meson by measuring B(D+ --> mu+nu) = (4.40 +/-0.66(+0.09)(-0.12) x 10(-4) using 281 pb(-1) of data taken on phi(3770) the resonance with the CLEO-c detector. We find fD+ = (222.6 +/- 16.7(+2.8)(-3.4)) MeV, and compare with current theoretical calculations. We also set a 90% confidence upper limit on B(D+e+nu)< 2.4 x 10(-5) which constrains new physics models.

Journal Article↗
PubMed2005

Search for rare and forbidden decays D+ --> h+/- e+/- e+.

Using 0.8 x 10(6) D+ D- pairs collected with the CLEO-c detector at the psi(3770) resonance, we have searched for flavor-changing neutral current and lepton-number-violating decays of D+ mesons to final states with dielectrons. We find no indication of either, obtaining 90% confidence level upper limits of B(D+ --> pi+ e+ e-) < 7.4 x 10(-6), B(D+ --> pi- e+ d+) < 3.6 x 10(-6), B(D+ --> K+ e+ e-) < 6.2 x 10(-6), and B(D+ --> K- e+ e+) < 4.5 x 10(-6).

Journal Article↗
PubMed2005

Absolute branching fraction measurements of exclusive D0 semileptonic decays.

With the first data sample collected by the CLEO-c detector at the psi(3770) resonance we have studied four exclusive semileptonic decays of the D0 meson. Our results include the first observation and absolute branching fraction measurement for D0 --> p-e+ve and improved measurements of the absolute branching fractions for D0 decays to K-e+ve, pi-e+ve, and K*-e+ve.

Journal Article↗
PubMed2005

Measurement of absolute hadronic branching fractions of D mesons and e+e- -->DD cross sections at Ec.m.=3773 MeV.

Using 55.8 pb(-1) of e+e- collisions recorded at the psi(3770) resonance with the CLEO-c detector at CESR, we determine absolute hadronic branching fractions of charged and neutral D mesons using a double tag technique. Among measurements for three D0 and six D+ modes, we obtain reference branching fractions B(D0-->K-pi+)=(3.91+/-0.08+/-0.09)% and B(D+-->K-pi+pi+)=(9.5+/-0.2+/-0.3)%, where the uncertainties are statistical and systematic, respectively. Final state radiation is included in these branching fractions by allowing for additional, unobserved, photons in the final state. Using a determination of the integrated luminosity, we also extract the cross sections sigma(e+e- -->D0D0)=(3.60+/-0.07(+0.07)(-0.05)) nb and sigma(e+e- -->D+D-)=(2.79+/-0.07(+0.10)(-0.04)) nb.

Journal Article↗
PubMed2005

Observation of the hc(1P1) state of charmonium.

The h(c)((1)P(1)) state of charmonium has been observed in the reaction psi(2S) --> pi(0)h(c) --> (gammagamma)(gammaeta(c)) using 3.08 x10(6) psi(2S) decays recorded in the CLEO detector. Data have been analyzed both for the inclusive reaction, where the decay products of the eta(c) are not identified, and for exclusive reactions, in which eta(c) decays are reconstructed in seven hadronic decay channels. We find M(h(c)) = 3524.4 +/- 0.6 +/- 0.4 MeV which corresponds to a hyperfine splitting DeltaM(hf)(1P) triple-bond pi(0)h(c)) x B(h(c) --> gammaeta(c)) = (4.0 +/- 0.8 +/- 0.7) x 10(-4).

Journal Article↗
PubMed2005

Observation of thirteen new exclusive multibody hadronic decays of the psi(2S).

Using data accumulated with the CLEO detector corresponding to an integrated luminosity of [symbol: see text] = 5.63 pb(-1) on the peak of the psi(2S) [3.08 x 10(6) psi(2S) decays] and 20.70 pb(-1) at square root of[s] = 3.67 GeV, we report first measurements of the branching fractions for the following 13 decay modes of the psi(2S): eta3pi, &eta'3pi, rhoK+K-, K+K-pi+pi-pi0, 2(K+K-), 2(K+K-)pi0, rhopp, pppi+pi-pi0, etapp, ppK+K-, lambdalambdapi+pi-, lambdapK+, and lambdapK+pi+pi-, and more precise measurements of 8 previously measured modes: 2(pi+pi-), rhopi+pi-, 2(pi+pi-)pi0, omegapi+pi-, K+K-pi+pi-, omegaK+K-, phiK+K-, and pppi+pi-. We also report new branching fraction measurements of phipi+pi- and omegapp and upper limits for etapi+pi-, etaK+K-, and phivpp. Results are compared, where possible, with the corresponding J/psi branching ratios to provide new tests of the 12% rule.

Journal Article↗
PubMed2005

Branching fractions for psi(2S)-to-J/psi transitions.

We describe new measurements of the inclusive and exclusive branching fractions for psi(2S) transitions to J/psi using e(+)e(-) collision data collected with the CLEO detector operating at CESR. All branching fractions and ratios of branching fractions reported here represent either the most precise measurements to date or the first direct measurements. Indirectly and in combination with other CLEO measurements, we determine B(chi(cJ) --> gamma(J/psi)) and B[psi(2S) --> light hadrons].

Journal Article↗
PubMed2005

Levels of CSF prostaglandin E2, cognitive decline, and survival in Alzheimer's disease.

BACKGROUND: Although epidemiological, clinical, and experimental evidence indicates that the inducible isoform of cyclo-oxygenase (COX-2) may be involved in the pathogenesis of several neurodegenerative disorders, the mechanisms whereby COX-2 contributes to Alzheimer's disease are largely unknown. OBJECTIVE: To undertake a longitudinal study of CSF levels of a major product of COX activity, prostaglandin E2 (PGE2), in relation to cognitive decline and survival in patients with Alzheimer's disease. METHODS: CSF PGE2 was measured on at least three annual visits in 35 controls and 33 Alzheimer patients (26 necropsy confirmed) who completed the Cambridge cognitive assessment (CAMCOG). RESULTS: Compared with controls, CSF PGE2 was higher in patients with mild memory impairment, but lower in those with more advanced Alzheimer's disease. The median survival time of patients with higher initial PGE2 levels was five years longer than those with lower levels. CONCLUSIONS: COX activity in Alzheimer's disease varies with stage of the disease. PGE2 levels correlate positively with patient survival. These findings suggest that inhibition of COX activity does not represent a major target for the pharmacological treatment of Alzheimer's disease.

Aged↗
PubMed2005

Improved measurement of the form factors in the decay lambda+c-->lambda + nue.

Using the CLEO detector at the Cornell Electron Storage Ring, we have studied the distribution of kinematic variables in the decay lambda(+)(c)lambda--> e(+)nu(e). By performing a four-dimensional maximum likelihood fit, we determine the form factor ratio, R= f(2)/f(1) = -0.31 +/- 0.05(stat) +/- 0.04(syst), the pole mass, M(pole) = [2.21 +/- 0.08(stat) +/- 0.14(syst)] GeV/c(2), and the decay asymmetry parameter of the lambda(+)(c), alpha (lambda(c)) = -0.86 +/-0.03(stat) +/- 0.02(syst), for q(2) = 0.67 (GeV/c(2))(2). We compare the angular distributions of the lambda(+)(c) and lambda(-)(c) and find no evidence for CP violation: A(lambda(c)) = (alpha(lambda(c)) + alpha (lambda(c)))/(alpha(lambda(c))-alpha(lambda(c))) = 0.00 +/- 0.03(stat) +/- 0.01(syst) +/- 0.02, where the third error is from the uncertainty in the world average of the CP-violating parameter, A(lambda), for ppi(-).

Journal Article↗
PubMed2005

The genome of the social amoeba Dictyostelium discoideum.

The social amoebae are exceptional in their ability to alternate between unicellular and multicellular forms. Here we describe the genome of the best-studied member of this group, Dictyostelium discoideum. The gene-dense chromosomes of this organism encode approximately 12,500 predicted proteins, a high proportion of which have long, repetitive amino acid tracts. There are many genes for polyketide synthases and ABC transporters, suggesting an extensive secondary metabolism for producing and exporting small molecules. The genome is rich in complex repeats, one class of which is clustered and may serve as centromeres. Partial copies of the extrachromosomal ribosomal DNA (rDNA) element are found at the ends of each chromosome, suggesting a novel telomere structure and the use of a common mechanism to maintain both the rDNA and chromosomal termini. A proteome-based phylogeny shows that the amoebozoa diverged from the animal-fungal lineage after the plant-animal split, but Dictyostelium seems to have retained more of the diversity of the ancestral genome than have plants, animals or fungi.

ATP-Binding Cassette Transporters↗
PubMed2005

Keratinocyte growth factor therapy in murine oleic acid-induced acute lung injury.

Alveolar type II (ATII) cell proliferation and differentiation are important mechanisms in repair following injury to the alveolar epithelium. KGF is a potent ATII cell mitogen, which has been demonstrated to be protective in a number of animal models of lung injury. We have assessed the effect of recombinant human KGF (rhKGF) and liposome-mediated KGF gene delivery in vivo and evaluated the potential of KGF as a therapy for acute lung injury in mice. rhKGF was administered intratracheally in male BALB/c mice to assess dose response and time course of proliferation. SP-B immunohistochemistry demonstrated significant increases in ATII cell numbers at all rhKGF doses compared with control animals and peaked 2 days following administration of 10 mg/kg rhKGF. Protein therapy in general is very expensive, and gene therapy has been suggested as a cheaper alternative for many protein replacement therapies. We evaluated the effect of topical and systemic liposome-mediated KGF-gene delivery on ATII cell proliferation. SP-B immunohistochemistry showed only modest increases in ATII cell numbers following gene delivery, and these approaches were therefore not believed to be capable of reaching therapeutic levels. The effect of rhKGF was evaluated in a murine model of OA-induced lung injury. This model was found to be associated with significant alveolar damage leading to severe impairment of gas exchange and lung compliance. Pretreatment with rhKGF 2 days before intravenous OA challenge resulted in significant improvements in PO2, PCO2, and lung compliance. This study suggests the feasibility of KGF as a therapy for acute lung injury.

Acute Disease↗
PubMed2005

Photon transitions in Upsilon(2S) and Upsilon(3S) decays.

We have studied the inclusive photon spectra in Upsilon(2S) and Upsilon(3S) decays using a large statistics data sample obtained with the CLEO III detector. We present the most precise measurements of electric dipole (E1) photon transition rates and photon energies for Upsilon(2S) --> gammachi(bJ)(1P) and Upsilon(3S) --> gammachi(bJ)(2P) (J = 0, 1, 2). We measure the rate for a rare E1 transition Upsilon(3S) --> gammachi(b0)(1P) for the first time. We also set upper limits on the rates for the hindered magnetic dipole (M1) transitions to the eta(b)(1S) and eta(b)(2S) states.

Journal Article↗
PubMed2005

Healthy eating, activity and obesity prevention: a qualitative study of parent and child perceptions in Australia.

Preventative health strategies incorporating the views of target participants have improved the likelihood of success. This qualitative study aimed to elicit child and parent views regarding social and environmental barriers to healthy eating, physical activity and child obesity prevention programmes, acceptable foci, and appropriate modes of delivery. To obtain views across a range of social circumstances three demographically diverse primary schools in Victoria, Australia were selected. Children in Grades 2 (aged 7-8 years) and 5 (aged 10-11 years) participated in focus groups of three to six children. Groups were semi-structured using photo-based activities to initiate discussion. Focus groups with established parent groups were also conducted. Comments were recorded, collated, and themes extracted using grounded theory. 119 children and 17 parents participated. Nine themes emerged: information and awareness, contradiction between knowledge and behaviour, lifestyle balance, local environment, barriers to a healthy lifestyle, contradictory messages, myths, roles of the school and family, and timing and content of prevention strategies for childhood obesity. In conclusion, awareness of food 'healthiness' was high however perceptions of the 'healthiness' of some sedentary activities that are otherwise of benefit (e.g. reading) were uncertain. The contradictions in messages children receive were reported to be a barrier to a healthy lifestyle. Parent recommendations regarding the timing and content of childhood obesity prevention strategies were consistent with quantitative research. Contradictions in the explicit and implicit messages children receive around diet and physical activity need to be prevented. Consistent promotion of healthy food and activity choices across settings is core to population prevention programmes for childhood obesity.

Child↗
PubMed2005

Observation of 1(-)0(-) final states from psi(2S) decays and e(+)e(-) annihilation.

Using CLEO data collected from CESR e(+)e(-) collisions at the psi(2S) resonance and nearby continuum at sqrt[s]=3.67 GeV, we report the first significantly nonzero measurements of light vector-pseudoscalar hadron pair production (including rhopi, omegapi, rhoeta, and K(*0)K0 ) and the pi(+)pi(-)pi(0) final state, both from psi(2S) decays and direct e(+)e(-) annihilation.

Journal Article↗
PubMed2005

The effects of anaesthesia on cortical stimulation in rats: a functional MRI study.

The purpose of this study was to investigate the affects of equithesin and isoflurane on cortical activation in the rat using fMRI. Eight healthy male Sprauge-Dawley rats were anaesthetised separately with isoflurane and equithesin following a week in between. Functional EPI images were acquired in axial and sagittal orientations on a Bruker 47/30 Biospec system. Each experiment included repetitive air puffs over the right face region and was divided into 4 OFF (no stimulation) and 3 ON (repeated air puffs) periods. Changes in the BOLD-fMRI signal response were analysed using a box-car response function (SPM99) correlated against each voxel to determine regions of activation (p Corrected <0.0001, Z score>3.54). Neural activation was not detected when equithesin was used except in one rat compared to consistent activation with isoflurane in all 16 functional EPI scans. Equithesin appears to have effectively reduced brain activity in response to sensory stimuli. Isoflurane anaesthesia (1.6%) showed consistent, robust neural activations. It is therefore recommended that equithesin should be further investigated with other functional modalities or behavioural tests prior to consider it as an anaesthetic agent for future functional MRI studies.

Anesthesia↗