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J Turner

Publications and source records attributed to J Turner.

At least 37 records · Page 2Linked to original sources
PubMed2004

The impact of day care on socially disadvantaged families: an example of the use of process evaluation within a randomized controlled trial.

AIM: This paper describes a process evaluation that was conducted alongside a randomized controlled trial of out-of-home pre-school day care. The evaluation aimed to: (1) describe the intervention; (2) document the day care received by participating families; (3) describe the social context of the trial; and (4) provide data to assist in the interpretation of trial outcomes. METHODS: The setting for the trial was an out-of-home day care Centre in Hackney, East London. Process data were collected through the use of questionnaires, interviews, and researcher field-notes. Data from questionnaires were collected from 120 mothers and included data on 143 children. Interviews were undertaken with 21 participating mothers. Staff also completed questionnaires and the Head of the Centre was interviewed. The quality of care provided was assessed using the Early Childhood Environment Rating Scale. RESULTS: Process data collected during the trial suggest that the day care provided was education-led, flexible in catering to families' needs, and was of a very high quality. The social context of the trial resulted in financial pressures, which may well have influenced the intervention provided. Data collected through in-depth interviews suggested that it may be the flexibility of day care that is particularly important in allowing women to return to paid employment, but that the loss of benefits when starting work may have meant no increase in household income. CONCLUSION: The paper illustrates the value of conducting a process evaluation alongside a randomized trial, particularly where complex interventions are involved. In this case, where the intervention was not provided by the research team, the evaluation allowed an insight into the content of a multifaceted intervention, which is useful in interpreting the trial's results, and in explaining the possible effects of the social context on the intervention.

Adult↗
PubMed2004

Frequency and spatial distribution of environmental Campylobacter spp.

Humans are exposed to Campylobacter spp. in a range of sources via both food and environmental pathways. For this study, we explored the frequency and distribution of thermophilic Campylobacter spp. in a 10- by 10-km square rural area of Cheshire, United Kingdom. The area contains approximately 70, mainly dairy, farms and is used extensively for outdoor recreational activities. Campylobacter spp. were isolated from a range of environmental samples by use of a systematic sampling grid. Livestock (mainly cattle) and wildlife feces and environmental water and soil samples were cultured, and isolates were presumptively identified by standard techniques. These isolates were further characterized by PCR. Campylobacter jejuni was the most prevalent species in all animal samples, ranging from 11% in samples from nonavian wildlife to 36% in cattle feces, and was isolated from 15% of water samples. Campylobacter coli was commonly found in water (17%) and sheep (21%) samples, but rarely in other samples. Campylobacter lari was recovered from all sample types, with the exception of sheep feces, and was found in moderate numbers in birds (7%) and water (5%). Campylobacter hyointestinalis was only recovered from cattle (7%) and birds (1%). The spatial distribution and determinants of C. jejuni in cattle feces were examined by the use of model-based spatial statistics. The distribution was consistent with very localized within-farm or within-field transmission and showed little evidence of any larger-scale spatial dependence. We concluded that there is a potentially high risk of human exposure to Campylobacter spp., particularly C. jejuni, in the environment of our study area. The prevalence and likely risk posed by C. jejuni-positive cattle feces in the environment diminished as the fecal material aged. After we took into account the age of the fecal material, the absence or presence of rain, and the presence of bird feces, there was evidence of significant variation in the prevalence of C. jejuni-positive cattle feces between grazing fields but no evidence of spatial clustering beyond this resolution. The spatial pattern of C. jejuni is therefore consistent with that for an organism that is ubiquitous in areas contaminated with cattle feces, with a short-scale variation in infection intensity that cannot be explained solely by variations in the age of the fecal material. The observed pattern is not consistent with large-scale transmission attributable to watercourses, wildlife territories, or other geographical features that transcend field and farm boundaries.

Animals↗
PubMed2004

Gamma interferon production by bovine gamma delta T cells following stimulation with mycobacterial mycolylarabinogalactan peptidoglycan.

A large percentage of lymphocytes in the blood of cattle express the gamma delta T-cell receptor, but specific functions for these cells have not yet been clearly defined. There is evidence, however, that human, murine, and bovine gamma delta T cells have a role in the immune response to mycobacteria. This study investigated the ability of bovine gamma delta T cells to expand and produce gamma interferon (IFN-gamma) in response to stimulation with mycobacterial products. Bovine gamma delta T cells, isolated from the peripheral blood of healthy cattle, expanded following in vitro stimulation with live mycobacteria, mycobacterial crude cell wall extract, and Mycobacterium bovis culture filtrate proteins. In addition, purified gamma delta T cells, cocultured with purified monocytes and interleukin-2, consistently produced significant amounts of IFN-gamma in response to mycobacterial cell wall. The IFN-gamma-inducing component of the cell wall was further identified as a proteolytically resistant, non-sodium dodecyl sulfate-soluble component of the mycolylarabinogalactan peptidoglycan.

Animals↗
PubMed2004

Health care utilisation of prematurely born, preschool children related to hospitalisation for RSV infection.

BACKGROUND: In prematurely born infants with chronic lung disease (CLD), RSV hospitalisation is associated with increased health service utilisation and costs in the first two years after birth. AIMS: To determine whether RSV hospitalisation in the first two years was associated with chronic respiratory morbidity during the preschool years in prematurely born children who had had CLD. METHODS: Retrospective review of readmissions, outpatient attendances, and community care in years 2-4 and, at age 5 years, assessment of the children's respiratory status and their health related quality of life. Comparison was made of the results of children who had had at least one hospitalisation in the first two years after birth for RSV infection (RSV group) to those of the rest of the cohort. Participants were 190 of an original cohort of 235 infants with CLD and a median gestational age 27 (range 22-33) weeks. RESULTS: The 33 children in the RSV group, compared to the rest of the cohort, had a greater duration of hospital stay and more outpatient appointments. The RSV group had required more prescriptions for all treatments and respiratory medications, and more had used an inhaler. The cost of care of the RSV group was higher (median 2630 pounds sterling [4000 Euros, US4800 dollars], range 124-18,091 pounds sterling versus 1360 pounds sterling [2500 Euros, US3000 dollars], range 5-18 929 pounds sterling ) and their health related quality of life was lower. CONCLUSION: In prematurely born children who had developed CLD, RSV hospitalisation in the first two years was associated with chronic respiratory morbidity and increased cost of care.

Ambulatory Care↗
PubMed2004

Ethical and professional conduct of medical students: review of current assessment measures and controversies.

As medical education increasingly acknowledges the importance of the ethical and professional conduct of practitioners, and moves towards more formal assessment of these issues, it is important to consider the evidence base which exists in this area. This article discusses literature about the health needs and problems experienced by medical practitioners as a background to a review of the current efforts in medical education to promote ethical conduct and develop mechanisms for the detection and remediation of problems.

Behavior↗
PubMed2003

Activation marker expression on bovine peripheral blood gammadelta T cells during post-natal development and following vaccination with a commercial polyvalent viral vaccine.

Understanding the immunological function of bovine gammadelta T cells is essential for evaluating their role in the response to infectious agents and for determining the potential of targeting this population with vaccines. This study examined the age dependent changes of circulating CD2(+) and CD2(-) gammadelta T cells as well as differences in the expression of activation markers between these two populations. Changes in activation marker expression following vaccination with Vira Shield 5 are also discussed. CD62L was expressed on all CD2(-) gammadelta T cells but only a subset of CD2(+) gammadelta T cells and following vaccination there was a significant decrease in the percentage of CD2(-)/CD62L(+) gammadelta T cells but not CD2(+)/CD62L(+) gammadelta T cells. Both CD2(-) and CD2(+) gammadelta T cells consistently expressed high levels of CD44. The majority of both CD2(-) and CD2(+) gammadelta T cells also expressed CD45R, however, more of the CD2(-) cells were CD45R(neg/lo). Following vaccination there was a significant decrease in the percentage of CD2(-) and CD2(+) gammadelta T cells that expressed CD44 and CD45R. These data indicate significant differences in activation expression on CD2(-) and CD2(+) gammadelta T cells, which adds to the growing evidence that there may be functional as well as phenotypic differences between these two populations of bovine gammadelta T cells.

Age Factors↗
PubMed2002

Extremely low vertical-emittance beam in the accelerator test facility at KEK.

Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance.

Journal Article↗
PubMed2002

Microbial and nutrient pollution of coastal bathing waters in Mauritius.

The coastal pollution problem in Mauritius is exacerbated by the hydrogeology of the volcanic substratum. Bacterial contamination of bathing waters and nutrients, water temperature, salinity, and dissolved oxygen (DO) were monitored at three different spatial and temporal scales along the coastline of Mauritius during 1997-1998. Standard techniques for water sample collection and analysis set by the American Public Health Association [APHA. Standard methods for the examination of water and wastewater. 19th ed. Washington, DC: APHA, 1995.] were used at: (a) 16 sites around the island over a period of 7 months; (b) 12 stations along a recreational beach over an 18-month period; and (c) at an underground freshwater seepage point over 1 day. Total coliform (TC), faecal coliform (FC), and faecal streptococci (FS) contamination reported during all surveys varied randomly (e.g., with maximum densities in the ranges of 346-2020 TC, 130-2000 FC, and 180-1040 FS at one site) and at times exceeded the established EEC and Environment Protection Agency (EPA) standards for bathing water (e.g., in >90% of samples) to qualify for beach closure. Computed FC:FS ratios were used to pinpoint human faecal matter as the main source of contamination. Nitrate, phosphate, and silicate concentrations in seepage water were high (3600-9485, 38-105, and 9950-24,775 microg l(-1), respectively) and a cause for concern when compared with levels (5-845, 5-72, and 35-6570 microg l(-1), respectively) in cleaner lagoon water samples. Statistical analysis showed significant correlations (for TC and NO3: r=.75, P<.02; for TC and PO4: r=.779, P<.02; for TC and SiO4: r=.731, P<.05; for FC and NO3: r=.773, P<.02; for FC and SiO4: r=.727, P<.05; for FS and SiO4: r=.801 P<.01) between microbial densities and nutrients recorded, confirming the pathogen-contaminated water to be highly eutrophic. There is an urgency for Mauritius to properly address the issue of sewage treatment and wastewater discharge to safeguard its coastal environment, public health, and tourism expansion.

Enterobacteriaceae↗
PubMed2002

A clarification of transmission terms in host-microparasite models: numbers, densities and areas.

Transmission is the driving force in the dynamics of any infectious disease. A crucial element in understanding disease dynamics, therefore, is the 'transmission term' describing the rate at which susceptible hosts are 'converted' into infected hosts by their contact with infectious material. Recently, the conventional form of this term has been increasingly questioned, and new terminologies and conventions have been proposed. Here, therefore, we review the derivation of transmission terms, explain the basis of confusion, and provide clarification. The root of the problem has been a failure to include explicit consideration of the area occupied by a host population, alongside both the number of infectious hosts and their density within the population. We argue that the terms 'density-dependent transmission' and 'frequency-dependent transmission' remain valid and useful (though a 'fuller' transmission term for the former is identified), but that the terms 'mass action', 'true mass action' and 'pseudo mass action' are all unhelpful and should be dropped. Also, contrary to what has often been assumed, the distinction between homogeneous and heterogeneous mixing in a host population is orthogonal to the distinction between density- and frequency-dependent transmission modes.

Disease Transmission, Infectious↗
PubMed2002

Home oxygen status and rehospitalisation and primary care requirements of infants with chronic lung disease.

OBJECTIVES: To determine whether the rehospitalisation and primary care requirements of infants with chronic lung disease (CLD) during the first two years after birth were influenced by a requirement for supplementary oxygen after discharge from the neonatal intensive care unit. METHODS: Review of records from both the hospital and general practitioner. PATIENTS: 235 infants, median gestational age 27 (range 22-31) weeks, 88 of whom were receiving supplementary oxygen when discharged home. RESULTS: Overall, the infants required a median of 2 (range 0-20) admissions per patient, 8 (0-41) outpatient attendances, 13 (0-76) contacts with the general practitioner, and 17 (0-169) consultations with other primary healthcare professionals. The home oxygen patients required significantly more and longer admissions (p < 0.01) and more outpatient attendances (p < 0.05). The total cost of care per infant of the home oxygen group was greater (p < 0.001); this reflected higher costs for hospital stay (p < 0.01), total inpatient care (p < 0.01), and primary care drugs (p < 0.01). CONCLUSION: Despite routine use of antenatal steroids and postnatal surfactant, certain patients with CLD, particularly those who receive home oxygen treatment, show high rates of utilisation of health service resources after discharge from the neonatal care unit.

Analysis of Variance↗
PubMed2002

The acceptability of an emergency medical dispatch system to people who call 999 to request an ambulance.

OBJECTIVE: To determine the acceptability of an emergency medical dispatch (EMD) system to people who call 999 to request an ambulance. METHODS: Postal questionnaires to two systematic random samples of approximately 500 named callers to one ambulance service before, and one year after, the introduction of EMD. RESULTS: The response rate was 72% (355 of 493) before, and 63% (297 of 466) after, EMD. There was a reduction, from 81% (284 of 349) to 70% (200 of 286), in the proportion of callers who found all the questions asked by the call taker relevant, although this did not adversely affect the proportion of callers who were very satisfied with the 999 call, which increased from 78% (268 of 345) to 86% (247 of 287). The proportion of callers who reported receiving first aid advice increased from 7% (23 of 323) to 43% (117 of 272) and general information from 13% (41 of 315) to 58% (157 of 269). Satisfaction levels with the amount of advice given increased, while satisfaction with response times remained stable at 76% (254 of 320) very satisfied before and 78% (217 of 279) after EMD. The proportion of respondents very satisfied with the service in general increased from 71% (238 of 336) to 79% (220 of 277). There was evidence in respondents' written comments of two potential problems with EMD from the caller's viewpoint. Firstly, some callers were advised to take actions that were subsequently not needed; secondly, a small number of callers felt that the ambulance crew did not treat the situation as seriously as they would have liked. CONCLUSIONS: Introducing EMD increases the amount of first aid and general advice given to callers, and satisfaction with these aspects of the service, while maintaining satisfaction with response times. Overall satisfaction with the service increased. However, some changes may be needed to prevent a small amount of dissatisfaction directly associated with EMD.

Ambulances↗
PubMed2001

amiA is a negative regulator of acetamidase expression in Mycobacterium smegmatis.

BACKGROUND: The acetamidase of Mycobacterium smegmatis is a highly inducible enzyme. Expression of this enzyme is increased 100-fold when the substrate acetamide is present. The acetamidase gene is found immediately downstream of three open reading frames. Two of these are proposed to be involved in regulation. RESULTS: We constructed a deletion mutant in one of the upstream ORFs (amiA). This mutant (Mad1) showed a constitutively high level of acetamidase expression. We identified four promoters in the upstream region using a beta-galactosidase reporter gene. One of these (P2) was inducible in the wild-type, but was constitutively active in Mad1. CONCLUSIONS: These results demonstrate that amiA encodes a negative regulatory protein which interacts with P2. Since amiA has homology to DNA-binding proteins, it is likely that it exerts the regulatory effect by binding to the promoter to prevent transcription.

Amidohydrolases↗
PubMed2001

Induction of AP-2alpha expression by adenoviral infection involves inactivation of the AP-2rep transcriptional corepressor CtBP1.

AP-2 transcription factors execute important functions during embryonic development and malignant transformation. Recently, we have isolated a transcriptional repressor of AP-2alpha expression, the novel Krüppel-related zinc finger protein AP-2rep (Klf12). Here, we show that repression of AP-2alpha transcription by AP-2rep is dependent on an N-terminal PVDLS motif that interacts specifically with the corepressor CtBP1 both in vivo and in vitro. This interaction motif was previously identified in the C-terminal region of the adenoviral oncoprotein E1A. Infection of both HeLa and PA-1 cells with adenovirus type 5 strongly induced AP-2alpha mRNA. Consistently, E1A was necessary and sufficient to mediate up-regulation of AP-2alpha. Transiently transfected wild-type E1A protein activated an AP-2rep sensitive cis-regulatory element of the AP-2alpha promoter, but E1A protein harboring a mutation in the PVDLS motif failed to activate. In summary, we conclude that the adenoviral oncoprotein E1A activates transcription from the endogenous AP-2alpha gene, an effect that involves transcriptional derepression of the AP-2alpha promoter by interaction of E1A with the AP-2rep corepressor CtBP1.

Adenoviridae↗
PubMed2001

Contribution of individual amino acids to the nucleic acid binding activities of the Xenopus zinc finger proteins TFIIIIA and p43.

Xenopus transcription factor IIIIA (TFIIIA) binds to both 5S RNA and the 5S RNA gene in immature oocytes, an interaction mediated by nine zinc fingers. To determine the role of the central zinc fingers of the protein in these nucleic acid binding activities, a series of substitution mutants of TFIIIA were constructed and expressed as recombinant proteins in Escherichia coli. The mutant proteins were purified to homogeneity and analyzed for DNA and RNA binding activities using a nitrocellulose filter binding assay. Finger 5, but not finger 4, 6, or 7, is involved in sequence-specific binding to the 5S RNA gene. A TWT amino acid motif in finger 6 makes a significant contribution to the binding of TFIIIA to 5S RNA, while mutations in fingers 4, 5, and 7 have little or no effect on RNA binding by TFIIIA. In striking contrast, a TWT motif in finger 6 of p43, another Xenopus zinc finger protein that binds to 5S RNA, is not necessary for 5S RNA binding by this protein. Evidence for the presence of inhibitory finger-finger interactions that limit the nucleic acid binding properties of individual zinc fingers within TFIIIA and p43 is discussed.

Amino Acid Motifs↗
PubMed2001

Crystal structure of the mitotic spindle kinesin Eg5 reveals a novel conformation of the neck-linker.

Success of mitosis depends upon the coordinated and regulated activity of many cellular factors, including kinesin motor proteins, which are required for the assembly and function of the mitotic spindle. Eg5 is a kinesin implicated in the formation of the bipolar spindle and its movement prior to and during anaphase. We have determined the crystal structure of the Eg5 motor domain with ADP-Mg bound. This structure revealed a new intramolecular binding site of the neck-linker. In other kinesins, the neck-linker has been shown to be a critical mechanical element for force generation. The neck-linker of conventional kinesin is believed to undergo an ordered-to-disordered transition as it translocates along a microtubule. The structure of Eg5 showed an ordered neck-linker conformation in a position never observed previously. The docking of the neck-linker relies upon residues conserved only in the Eg5 subfamily of kinesin motors. Based on this new information, we suggest that the neck-linker of Eg5 may undergo an ordered-to-ordered transition during force production. This ratchet-like mechanism is consistent with the biological activity of Eg5.

Adenosine Diphosphate↗