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K Jones

Publications and source records attributed to K Jones.

At least 109 records · Page 6Linked to original sources
PubMed2000

Effects of teacher feedback on the reputations and peer perceptions of children with behavior problems.

We explored whether teacher feedback modified children's preferences and perceptions of a target child with behavior problems. First- and second-grade children (M age = 7.8 years) viewed a videotape of a target actor presented as having a liked, average, or disliked reputation. A second videotape depicted a teacher's verbal responses to the target's behavior as (a) positive, (b) neutral-salient, or (c) corrective. Both salience and valence of teacher feedback were assessed. Main effects of feedback and reputation indicated that feedback had at least minimal effects at each level of the target's reputation. Teacher feedback is discussed with respect to its effects on perceptions of behavior versus affective responses toward behavior-problem children. A significant interaction showed that when combined with a liked reputation, positive and neutral-salient feedback conditions increased the salience and positive evaluation of the target child, thus illustrating the importance of considering nonevaluative teacher attention in combination with children's reputational status.

Child↗
PubMed2000

Safety and biological efficacy of a lipid-CFTR complex for gene transfer in the nasal epithelium of adult patients with cystic fibrosis.

Gene transfer is an attractive option to treat the basic defect in cystic fibrosis. In a double-blind, placebo-controlled, rising-dose tolerance study in the nasal epithelium, we tested the safety and efficacy of a cationic liposome [p-ethyl-dimyristoylphosphadityl choline (EDMPC) cholesterol] complexed with an expression plasmid containing hCFTR cDNA. Eleven adult CF patients were studied in a protocol that allowed comparisons within individual subjects: vector and placebo were sprayed into alternate nostrils at intervals over 7 h. After dosing, vector-specific DNA was present in nasal lavage of all subjects for up to 10 days. There were no adverse events. The vector-treated epithelium did not exhibit a significant increase in CFTR-mediated Cl- conductance from baseline and was not different from the placebo-treated nostril: mean deltaCFTR Cl- conductance, mV +/- SEM, -1.6+/-0.4 vs -0.6+/-0.4, respectively. CFTR-mediated Cl- conductance increased toward normal during repetitive nasal potential difference measurements over the 3 days before dosing which influenced the postdosing calculations. No vector-specific mRNA was detected in the nasal epithelial scrape biopsies, although endogenous CFTR mRNA was detected in all subjects. We conclude that the lipid-DNA complex is safe, but did not produce consistent evidence of gene transfer to the nasal epithelium by physiologic or molecular measures.

Adult↗
PubMed2000

Environmental Accountability: Who's Kidding Whom?

International declarations and charters have been produced to encourage and support higher education institutions (HEIs) to address their environmental responsibilities. This paper discusses the results of a critical examination of a range of international HEIs that have signed the global environmental Talloires Declaration. It also assesses the Talloires Secretariat (University Leaders for a Sustainable Future, ULSF) and the extent to which this has been a primary stimulus. An international survey was undertaken and the results presented in a discursive format in order to highlight key driving forces, barriers, and opportunities for environmental responsibility in HEIs. Analysis reveals that they occur on two distinct and evolving levels: the macro national framework level and the micro institutional framework level. Survey responses revealed that none of the HEIs have an embedded institutional environmental culture and most did not have all the micro institutional mechanisms in place for an integrated university-wide environmental response. Many of the institutional barriers to environmental responsibility occurred as a result of this lack of strategy. The most significant institutional opportunity cited was enthusiastic individuals, particularly those at senior management or directorate level, and these individuals were found to be a key driving force. Results also showed that environmental reporting along the lines developed by the private sector is a flexible mechanism that can stimulate progress internally and externally and can be cost effectively disseminated via the World Wide Web. Moreover the survey results indicate that ULSF is not currently a primary stimulus for institution wide action.

Journal Article↗
PubMed2000

An immunoassay for the measurement of sirolimus.

OBJECTIVE: This study assessed the performance characteristics of a new microparticle enzyme immunoassay (MEIA) for the determination of sirolimus in whole blood. BACKGROUND: In clinical investigatory studies, dose adjustments of the immunosuppressive drug sirolimus have been carried out using either high-performance liquid chromatography (HPLC) or, more recently, this investigational immunoassay kit based on the MEIA technique. METHODS: Calibration was made over the linear range 0 to 30 ng/mL. Inaccuracy and imprecision were assessed by means of 3 control samples supplied with the kit (5, 11, and 22 ng/mL) and dilution of an above-quantitation-limit sample (154 ng/mL). Specificity was determined by the addition of 2 sirolimus metabolites to sirolimus-free human whole blood or to I of the control samples supplied with the kit. In addition, whole-blood samples from patients receiving either cyclosporine or tacrolimus (N = 24) were analyzed for sirolimus. A comparison of the MEIA and a validated HPLC/MS/MS assay analyzed both pooled samples from patients receiving sirolimus and spiked samples (sirolimus 2-60 ng/mL). In a more extensive comparison of patient samples measured by the MEIA assay, a validated HPLC assay with UV detection (HPLC-UV) was used (HPLC-UV sirolimus 7-64 ng/mL). RESULTS: Inaccuracy (between-run) was < or =16.2% at all 4 concentrations (N = 5). Within-assay imprecision (repeatability) was <6% (N = 5), and between-assay imprecision (reproducibility) for the same samples was < 11% (N = 5). Recovery, assessed by means of 3 in-house control samples prepared in both fresh and previously frozen sirolimus-free human whole blood, ranged from 93.9% to 109.5%. The limit of detection, determined by dilution of the lowest nonzero calibrator (3 ng/mL), was set at 1 ng/mL, at which repeatability was 20.5% (N = 5). Five ng/mL of hydroxysirolimus cross-reacted with the assay by a mean of between 44% and 50% (N = 4); 5 ng/mL of 41-O-demethylsirolimus cross-reacted with the assay by a mean of between 86% and 127% (N = 4). Assay specificity was further challenged by ethylenediamine-tetraacetic acid (EDTA)-whole-blood samples from transplant patients not receiving sirolimus. These samples had tacrolimus and cyclosporine concentrations of 7.8 to 15.9 ng/mL and 38 to 485 microg/L, respectively. The median result was 0 ng/mL (third quartile, 0.7 ng/mL; maximum, 1.4 ng/mL); no value was above the lowest nonzero calibrator. The results of the comparison between the MEIA and the HPLC/MS/MS assay showed mean positive biases of 21% and 8% for the MEIA in measuring sirolimus in pooled patient samples and spiked samples, respectively. The results of the comparison of the MEIA and HPLC-UV median sirolimus concentrations were 18.2 and 20.1. Whole-blood samples anticoagulated with EDTA and containing sirolimus were stable for analysis by MEIA for 3 freeze-thaw cycles when stored at -20 degrees C and for 10 days when stored at 4 degrees C or at ambient temperature. A decline in sirolimus concentration occurred when samples were stored at 37 degrees C. CONCLUSION: The MEIA showed suitable precision across a clinically relevant concentration range. In terms of patient management, the practical significance of cross-reactivity with sirolimus metabolites remains to be assessed.

Antibody Specificity↗
PubMed2000

Proficiency-testing issues relating to sirolimus.

BACKGROUND: A need exists to document laboratory proficiency to (1) compare results produced by different analytical techniques and (2) ensure consistency of results from multiple testing sites. OBJECTIVES: To enable concentration-controlled studies of sirolimus to proceed with confidence, proficiency-testing schemes were put in place at laboratories selected to act as reference laboratories. The feasibility of establishing an ongoing proficiency-testing scheme was addressed with respect to sample stability. The scheme was then used to test proficiency for the measurement of sirolimus in 3 blinded samples each month. METHODS: The method chosen for measurement of sirolimus was a prototype microparticle enzyme immunoassay. Initially, 15 laboratories were asked to analyze a series of 85 blinded samples that tested their inaccuracy, repeatability, and reproducibility for the measurement and their ability to dilute over-range samples competently. Both blood samples spiked with sirolimus and pooled blood samples from patients receiving the drug were circulated to a maximum of 50 laboratories. RESULTS: Overall, both inaccuracy and imprecision were acceptable by predefined criteria. Inaccuracy for the immunoassay (percentage difference of the measured value against the nominal value) averaged -5% (95% CI, -9% to -1%). The mean percentage difference between the immunoassay and a high-performance liquid chromatographic assay with mass-spectrometric detection for the measurement of sirolimus in pooled samples (n = 5) from patients receiving the drug was 29% (95% CI, 24% to 34%). CONCLUSION: The techniques documented here as part of the International Sirolimus Proficiency Testing Scheme could be applied to other clinical studies requiring protocol-driven dosing adjustments based on sirolimus measurements, irrespective of analytical technique used.

Chromatography, High Pressure Liquid↗
PubMed2000

Death and deprivation: an exploratory analysis of deaths in the health and lifestyle survey.

An analysis is undertaken of deaths of respondents in the UK- representative Health and Lifestyle Survey. The sample was originally interviewed in 1984/5 and followed initially until May 1997. Using multilevel logistic and Cox-proportional hazards models, the relationships between death and a wide range of social circumstances and behaviours is explored. It is found that place deprivation interacts with individual social class in accounting for variations in mortality. This is the case even when account is taken of personal health-related behaviour. There appears to be some evidence of a threshold relationship such that the differential effects of social class are only found at high-levels of deprivation. No statistically significant interactions are found for social and behavioural variables, for behavioural and place deprivation variables, and for social and place deprivation variables with the exception of social class. The study is deliberately exploratory and a wide range of models have been fitted which will be subject to more rigorous evaluation as the HALS death study proceeds.

Health Behavior↗
PubMed2000

Predicting small-area health-related behaviour: a comparison of smoking and drinking indicators.

Health-related behaviours are of central importance to health promotion and to the promotion of enhanced population health. In the UK, localised knowledge of the quantitative dimensions of health-related behaviours is traditionally attained by conducting a costly sample survey. Such surveys seldom generate reliable data at scales more local than that of the health authority, they also need to be repeated regularly. This paper outlines an alternative framework for generating statistics on small-area health related behaviours using routinely available data from the annual Health Survey for England (N = 17,000) and the decennial Population Census. Using a multilevel modelling approach nesting individuals within postcode sectors within health authorities, and focusing on the prevalence of smoking and 'problem' drinking, the paper comprises four sections: a consideration of the modelling strategy, a comparison of the smoking and drinking models, an outline of the estimation strategy, and the presentation and discussion of ward-level estimates of smoking and drinking behaviour for England. The paper concludes that the method is better at estimating smoking than drinking but that it offers a feasible, cheap and more informative alternative to the survey approach to the generation of information on smoking and drinking behaviour.

Alcohol Drinking↗
PubMed2000

Authors' reply

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Journal Article↗
PubMed2000

Diaries of evidence-based tutors: beyond 'numbers needed to teach'...

Interprofessional evidence-based health care courses have been held throughout the UK over the last few years, modelled on the approach used in McMaster University of using problem-based facilitated small-group formats to achieve the stated goals. Both delegates and tutors have been aware of the tensions which are inherent within these courses between: (a) the variation in learning cultures which is exhibited by the delegates and the effect this has on processes (i.e. the tension between the reductionist approach of bioscience and the more qualitative leanings of the applied and 'caring' disciplines); and (b) the conflict which arises between the goal of 'learning' applied healthcare biostatistics and the ability to leave the course with the skills to teach others. This qualitative study uses tutor-kept diaries to understand some of the tensions apparent to the teaching faculty during a week-long course in Wales, UK.

Evidence-Based Medicine↗
PubMed2000

Prescribing patterns for asthma by general practitioners in six European countries.

To assess the level of concordance with international consensus on asthma management, we compared primary care prescribing patterns for asthma in different European countries. A prospective study of prescription items with an associated diagnostic label of asthma in patient consultations with a total of 235 general practitioners (GPs) from Belgium, England, Ireland, Italy, Northern Ireland, Portugal, Scotland and Spain was performed. A total of 101,544 consecutive consultations were recorded in autumns 1994 and 1995 of which 3595 (3.5%) were for patients with asthma and 3243 (3.2%) were for patients receiving a prescription for asthma. Overall, asthma consultations varied from 1.8% in Italy to 5.8% in Ireland (mean 3.4%, SD 1.6). Prescribed inhaled medications for children varied from 72% of the total asthma prescriptions in Ireland and Portugal to 82% in Northern Ireland (mean 79%, SD 8.1) and for adults 55% in Italy to 85% in Spain (mean 70%, SD 10). Inhaled corticosteroid usage for adults varied from 14% in Italy to 31% in Northern Ireland (mean 24%, SD 6.4). For children, beta2-agonist use varied from 24% in Italy to 67% in Spain (mean 45%, SD 13). Despite publication of international guidelines for the management of asthma, inter-country prescribing practices vary considerably and could be improved. The frequency of use of asthma as a diagnostic label also varies markedly.

Administration, Inhalation↗
PubMed2000

Modified Aloe barbadensis polysaccharide with immunoregulatory activity.

Aloe barbadensis polysaccharide was partially digested with cellulase and further purified by dialysis, stepwise ethanol precipitation, and size exclusion chromatography. Crude modified Aloe polysaccharide (MAP) activated macrophage cells and stimulated fibroblast growth. Under the same conditions, native Aloe barbadensis gel had no effect on macrophage activation. MAP prevented ultraviolet B (UVB) irradiation-induced immune suppression as determined by contact hypersensitivity (CHS) response in C3H/HeN mice. This in vivo activity was correlated with the activity of MAP to inhibit UVB irradiation-induced tumor necrosis factor alpha (TNF-alpha) release from human epidermoid carcinoma cells (KB cells). MAP with an average molecular weight of 80,000 Dalton (Da) contained mannose, galactose, and glucose in a ratio of 40:1.4:1.0. MAP was likely a linear, highly acetylated molecule.

Adjuvants, Immunologic↗
PubMed2000

Real-time transmission of full-motion echocardiography over a high-speed data network: impact of data rate and network quality of service.

UNLABELLED: With high-resolution network transmission required for telemedicine, education, and guided-image acquisition, the impact of errors and transmission rates on image quality needs evaluation. METHODS: We transmitted clinical echocardiograms from 2 National Aeronautics and Space Administration (NASA) research centers with the use of Motion Picture Expert Group-2 (MPEG-2) encoding and asynchronous transmission mode (ATM) network protocol over the NASA Research and Education Network. Data rates and network quality (cell losses [CLR], errors [CER], and delay variability [CVD]) were altered and image quality was judged. RESULTS: At speeds of 3 to 5 megabits per second (Mbps), digital images were superior to those on videotape; at 2 Mbps, images were equivalent. Increasing CLR caused occasional, brief pauses. Extreme CER and CDV increases still yielded high-quality images. CONCLUSIONS: Real-time echocardiographic acquisition, guidance, and transmission is feasible with the use of MPEG-2 and ATM with broadcast quality seen above 3 Mbps, even with severe network quality degradation. These techniques can be applied to telemedicine and used for planned echocardiography aboard the International Space Station.

Artifacts↗
PubMed2000

Consumed with worry: 'unsafe' alcohol consumption and self-reported problem drinking in England.

Using data from the 1994 Health Survey for England, logistic multivariate multilevel modelling techniques are used to investigate the simultaneous effect of individual demographic characteristics and socio-structural factors on self-reported problem drinking as revealed by CAGE scores and 'unsafe' levels of alcohol consumption. Whilst the influence of key socio-structural variables is broadly similar for both unsafe alcohol consumption and high CAGE scores, there are notable exceptions when results are examined by tenure group: those in the rented sector are more likely to be problem drinkers as revealed by CAGE, but less likely to consume 'unsafe' amounts of alcohol. Both dimensions of drinking behaviour are influenced by the consumption patterns of others in the household, with both likelihoods increasing as the average consumption of others in the household rises. After taking into account individual compositional variables, the research indicates that there is very little evidence for geographical variation remaining in these two dimensions of drinking behaviour. It is found that the proportion of the population whose drinking behaviour may be classed as (potentially) problematic via the CAGE responses is substantially less than the proportion consuming above recommended 'safe' levels. The research concludes, however, that the two measures are broadly similar in their relationship to social and structural variables. Tenure provides an exception to this conclusion and indicates a continuing need to take account of housing circumstances in developing an understanding of drinking behaviour.

Adolescent↗
PubMed2000

Activity of antibiotics used in human medicine for Campylobacter jejuni isolated from farm animals and their environment in Lancashire, UK.

A retrospective study of 96 Campylobacter jejuni isolated from farm animals and the environment showed that most were less susceptible than the NCTC type strain to nalidixic acid (MICs 4-32 mg/L), ciprofloxacin (MICs 1-2 mg/L) and erythromycin (MICs 16-64 mg/L), but had similar susceptibility to tetracycline (MICs 4-8 mg/L) and kanamycin (MICs 4-8 mg/L). None had the high MICs of ciprofloxacin (>32 mg/L) or erythromycin (1024 mg/L) typically associated with clinical resistance in this species. Some farms used antimicrobial agents, but there was no obvious association between the use of agents and the susceptibility of the isolates.

Animals↗
PubMed2000

Validity and reliability of a postoperative quality of recovery score: the QoR-40.

Quality of recovery after anaesthesia is an important measure of the early postoperative health status of patients. We attempted to develop a valid, reliable and responsive measure of quality of recovery after anaesthesia and surgery. We studied 160 patients and asked them to rate postoperative recovery using three methods: a 100-mm visual analogue scale (VAS), a nine-item questionnaire and a 50-item questionnaire; the questionnaires were repeated later on the same day. From these results, we developed a 40-item questionnaire as a measure of quality of recovery (QoR-40; maximum score 200). We found good convergent validity between QoR-40 and VAS (r = 0.68, P < 0.001). Construct validity was supported by a negative correlation with duration of hospital stay (rho = -0.24, P < 0.001) and a lower mean QoR-40 score in women (162 (SD 26)) compared with men (173 (17)) (P = 0.002). There was also good test-retest reliability (intra-class ri = 0.92, P < 0.001), internal consistency (Cronbach's alpha = 0.93, P < 0.001) and split-half coefficient (alpha = 0.83, P < 0.001). The standardized response mean, a measure of responsiveness, was 0.65. The QoR-40 was completed in less than 6.3 (4.9) min. We believe that the QoR-40 is a good objective measure of quality of recovery after anaesthesia and surgery. It would be a useful end-point in perioperative clinical studies.

Adolescent↗
PubMed2000

Evidence for placental abnormality as the major cause of mortality in first-trimester somatic cell cloned bovine fetuses.

The production of cloned animals is, at present, an inefficient process. This study focused on the fetal losses that occur between Days 30-90 of gestation. Fetal and placental characteristics were studied from Days 30-90 of gestation using transrectal ultrasonography, maternal pregnancy specific protein b (PSPb) levels, and postslaughter collection of fetal tissue. Pregnancy rates at Day 30 were similar for recipient cows carrying nuclear transfer (NT) and control embryos (45% [54/120] vs. 58% [11/19]), although multiple NT embryos were often transferred into recipients. From Days 30-90, 82% of NT fetuses died, whereas all control pregnancies remained viable. Crown-rump (CR) length was less in those fetuses that were destined to die before Day 90, but no significant difference was found between the CR lengths of NT and control fetuses that survived to Day 90. Maternal PSPb levels at Days 30 and 50 of gestation were not predictive of fetal survival to Day 90. The placentas of six cloned and four control (in vivo or in vitro fertilized) bovine pregnancies were compared between Days 35 and 60 of gestation. Two cloned placentas showed rudimentary development, as indicated by flat, cuboidal trophoblastic epithelium and reduced vascularization, whereas two others possessed a reduced number of barely discernable cotyledonary areas. The remaining two cloned placentas were similar to the controls, although one contained hemorrhagic cotyledons. Poor viability of cloned fetuses during Days 35-60 was associated with either rudimentary or marginal chorioallantoic development. Our findings suggest that future research should focus on factors that promote placental and vascular growth and on fetomaternal interactions that promote placental attachment and villous formation.

Animals↗
PubMed2000

Prevalence of headaches in football players.

BACKGROUND: Football coaches and team physicians rely heavily on players' reports of symptoms in deciding whether a player may return to the game after sustaining head trauma. The decision is made difficult by the wide variety of associated symptoms, some of which (e.g., headache is among the most common) may or may not be associated with serious head injury. More information is needed about the clinical significance of football-related headache. METHODS: To assess the frequency of headache associated with playing football, we analyzed responses to our questionnaire asking about incidence, frequency, and outcome of football-related headache from 443 football players (320 from college, 123 from high school). RESULTS: Eighty-five percent of respondents reported previous headache related to hitting in football. Asked specifically about their most recent game, 21% of respondents reported having had headache during that game. Of players who had headache, only 19% informed the team physician, trainer, or coach, and only 6% were removed from the game. Twenty-seven percent of respondents reported previous diagnosis of cerebral concussion by medical personnel. Defensive backs (25%), defensive linemen (19%), and offensive linemen (18%) were most likely to have headache, related to hitting. CONCLUSIONS: Our data confirm that posttraumatic headache is commonly associated with football participation and often goes unreported. Given that the most serious complications of head injuries (e.g., second-impact syndrome) occur infrequently, headache as an isolated symptom lacks specificity in predicting such complications in football players. Therefore, unless it persists or is accompanied by additional symptoms, headache alone may not reliably suggest the need to remove players from the game.

Adolescent↗