1,839 research outputs found
Transmission of multidrug-resistant tuberculosis in the UK: a cross-sectional molecular and epidemiological study of clustering and contact tracing
BACKGROUND: Between 2000 and 2012 the number of multidrug-resistant (MDR) tuberculosis cases in the UK increased from 28 per year to 81 per year. We investigated the proportion of MDR tuberculosis cases arising from transmission in the UK and associated risk factors. METHOD: We identified patients with MDR tuberculosis notified in England, Wales, and Northern Ireland between Jan 1, 2004, and Dec 31, 2007, by linking national laboratory and surveillance data. Data for laboratory isolates, including drug sensitivities and 24-mycobacterial interspersed repetitive-unit-variable-number tandem repeat (MIRU-VNTR) typing were obtained routinely from the National Tuberculosis Reference laboratories as part of national tuberculosis surveillance. We investigated clusters of cases with indistinguishable MIRU-VNTR profiles to identify epidemiological links. We calculated transmission using the n-1 method and established associated risk factors by logistic regression. We also assessed the likelihood of transmission to additional secondary active tuberculosis cases, identified through conventional contact tracing. FINDINGS: 204 patients were diagnosed with MDR tuberculosis in the study period; 189 (92·6%) had an MIRU-VNTR profile. We identified 12 clusters containing 40 individuals and 149 unique strains. The proportion of cases attributable to recent transmission, on the basis of molecular data, was 15% (40 cases clustered-12 clusters/189 with a strain type). The proportion of cases attributable to recent transmission (ie, transmission within the UK) after adjustment for epidemiological links was 8·5% (22 cases with epidemiological links-six clusters/189 cases with a strain type). Being UK born (odds ratio 4·81; 95% CI 2·03-11·36, p=0·0005) and illicit drug use (4·75; 1·19-18·96, p=0·026) were significantly associated with clustering. The most common transmission setting was the household but 21 of 22 of epidemiological links were missed by conventional contact tracing. 13 secondary active tuberculosis cases identified by conventional contact tracing were mostly contacts of patients with MDR tuberculosis from countries of high tuberculosis burden. 11 (85%) of 13 shared the same country of birth as the index case, of whom ten did not share a strain type or drug resistance pattern. INTERPRETATION: Transmission of MDR tuberculosis in the UK is low and associated with being UK born or illicit drug use. MIRU-VNTR typing with cluster investigation was more successful at identifying transmission events than conventional contact tracing. Individuals with tuberculosis who have had contact with a known MDR tuberculosis source case from a country of high tuberculosis burden should have drug-sensitivity testing on isolates to ensure appropriate treatment is given. FUNDING: Public Health England
Leprosy in England and Wales 1953-2012: surveillance and challenges in low incidence countries
OBJECTIVE: To review all notified cases of leprosy in England and Wales between 1953 and 2012. DESIGN: National surveillance study of all reported cases. SETTING: England and Wales. OUTCOME: Number and characteristics of reported cases. RESULTS: During this period, a total of 1449 leprosy cases were notified. The incidence fell from 356 new cases notified between 1953 and 1962 to 139 new cases between 2003 and 2012. Where data were available, leprosy was more common in men, 15-45 year olds and those from the Indian subcontinent. There was considerable undernotification in 2001-2012. CONCLUSIONS: The high level of under-reporting indicates a need for improved surveillance in the UK. Public Health England, in collaboration with the UK Panel of Leprosy opinion, has revised the UK Memorandum on Leprosy in order to provide updated guidance on diagnostic procedures, treatment, case management, contact tracing and notification
The KRAB Zinc Finger Protein Roma/Zfp157 Is a Critical Regulator of Cell-Cycle Progression and Genomic Stability.
Regulation of DNA replication and cell division is essential for tissue growth and maintenance of genomic integrity and is particularly important in tissues that undergo continuous regeneration such as mammary glands. We have previously shown that disruption of the KRAB-domain zinc finger protein Roma/Zfp157 results in hyperproliferation of mammary epithelial cells (MECs) during pregnancy. Here, we delineate the mechanism by which Roma engenders this phenotype. Ablation of Roma in MECs leads to unscheduled proliferation, replication stress, DNA damage, and genomic instability. Furthermore, mouse embryonic fibroblasts (MEFs) depleted for Roma exhibit downregulation of p21Cip1 and geminin and have accelerated replication fork velocities, which is accompanied by a high rate of mitotic errors and polyploidy. In contrast, overexpression of Roma in MECs halts cell-cycle progression, whereas siRNA-mediated p21Cip1 knockdown ameliorates, in part, this phenotype. Thus, Roma is an essential regulator of the cell cycle and is required to maintain genomic stability.This work was supported by a PhD studentship from A*STAR Singapore to T.L.F.H. and funding from the Medical Research Council to C.J.W. G.G. and J.E.S. are supported by an MRC core grant to LMB (U105178808).This is the final version of the article. It first appeared from Cell Press via http://dx.doi.org/10.1016/j.celrep.2016.03.07
Family composition and age at menarche: findings from the international Health Behaviour in School-Aged Children Study
This research was funded by The University of St Andrews and NHS Health Scotland.Background Early menarche has been associated with father absence, stepfather presence and adverse health consequences in later life. This article assesses the association of different family compositions with the age at menarche. Pathways are explored which may explain any association between family characteristics and pubertal timing. Methods Cross-sectional, international data on the age at menarche, family structure and covariates (age, psychosomatic complaints, media consumption, physical activity) were collected from the 2009–2010 Health Behaviour in School-aged Children (HBSC) survey. The sample focuses on 15-year old girls comprising 36,175 individuals across 40 countries in Europe and North America (N = 21,075 for age at menarche). The study examined the association of different family characteristics with age at menarche. Regression and path analyses were applied incorporating multilevel techniques to adjust for the nested nature of data within countries. Results Living with mother (Cohen’s d = .12), father (d = .08), brothers (d = .04) and sisters (d = .06) are independently associated with later age at menarche. Living in a foster home (d = −.16), with ‘someone else’ (d = −.11), stepmother (d = −.10) or stepfather (d = −.06) was associated with earlier menarche. Path models show that up to 89% of these effects can be explained through lifestyle and psychological variables. Conclusions Earlier menarche is reported amongst those with living conditions other than a family consisting of two biological parents. This can partly be explained by girls’ higher Body Mass Index in these families which is a biological determinant of early menarche. Lower physical activity and elevated psychosomatic complaints were also more often found in girls in these family environments.Publisher PDFPeer reviewe
Care Seeking Behavior of Chest Symptomatics: A Community Based Study Done in South India after the Implementation of the RNTCP
INTRODUCTION: With the creation of the Revised National TB Control Programme (RNTCP), tuberculosis services have become decentralized and more accessible. A 1997 study prior to RNTCP implementation reported that most chest symptomatics accessed first private health care facilities and a general dissatisfaction with government health facilities. The study was repeated post-RNTCP implementation to gain insight into the current care seeking behavior of chest symptomatics. METHODOLOGY: A cross-sectional community-based study carried out between March-August 2008 in 4 sites (2 rural [R] and 2 urban [U]) from the same two districts of Chennai and Madurai, southern India, as in the 1997 study. Six hundred and forty chest symptomatics were identified (R 314; U 326), and detailed interviews were done for 606 (R311; U295). RESULTS: Prevalence of chest symptomatics in the urban and rural areas were 2.7% and 4.9% respectively (p<0.01), and was found to increase with age (Chi-square for trend, p<0.01). Longer delays in seeking care were seen amongst symptomatics above 45 years of age (p 0.01), and those who had taken previous TB treatment (p=0.05). Overall, 50% (222/444) of the chest symptomatics approached a government health care facility first (R 142 (61%); U 80 (38%), p=or <0.001). This was significantly (p<0.001) more than were observed in the 1997 study, where only 38.4% approached a government facility first. Sixty two (28%) of the 222 made a second visit to a government facility (R26%; U31%), while 17% shifted to a private facility (R14%; U21%). Dissatisfaction with the health care facility was one of the major reasons expressed. CONCLUSIONS: It appears that the RNTCP has had an impact in the community with regard to the availability and accessibility of TB services in government health facilities. However the relatively high levels of subsequent shifting to private health facilities calls for urgent action to make government facilities more patients friendly with quality care facilities in the delivery of RNTCP services
Being a quantitative interviewer: qualitatively exploring interviewers' experiences in a longitudinal cohort study
<p>Abstract</p> <p>Background</p> <p>Many studies of health outcomes rely on data collected by interviewers administering highly-structured (quantitative) questionnaires to participants. Little appears to be known about the experiences of such interviewers. This paper explores interviewer experiences of working on a longitudinal study in New Zealand (the Prospective Outcomes of injury Study - POIS). Interviewers administer highly-structured questionnaires to participants, usually by telephone, and enter data into a secure computer program. The research team had expectations of interviewers including: consistent questionnaire administration, timeliness, proportions of potential participants recruited and an empathetic communication style. This paper presents results of a focus group to qualitatively explore with the team of interviewers their experiences, problems encountered, strategies, support systems used and training.</p> <p>Methods</p> <p>A focus group with interviewers involved in the POIS interviews was held; it was audio-recorded and transcribed. The analytical method was thematic, with output intended to be descriptive and interpretive.</p> <p>Results</p> <p>Nine interviewers participated in the focus group (average time in interviewer role was 31 months). Key themes were: 1) the positive aspects of the quantitative interviewer role (i.e. relationships and resilience, insights gained, and participants' feedback), 2) difficulties interviewers encountered and solutions identified (i.e. stories lost or incomplete, forgotten appointments, telling the stories, acknowledging distress, stories reflected and debriefing and support), and 3) meeting POIS researcher expectations (i.e. performance standards, time-keeping, dealing exclusively with the participant and maintaining privacy).</p> <p>Conclusions</p> <p>Interviewers demonstrated great skill in the way they negotiated research team expectations whilst managing the relationships with participants. Interviewers found it helpful to have a research protocol in place in the event of sensitive situations - this appeared to alleviate the pressure on interviewers to carry the burden of responsibility. Interviewers are employed to scientifically gather quantitative data, yet their effectiveness relies largely on their humanity. We propose that the personal connection generated between the interviewers and participants was important, and enabled successful follow-up rates for the study. The enjoyment of these relationships was crucial to interviewers and helped balance the negative aspects of their role. Our results suggest that experienced quantitative interviewers endeavour, as do many qualitative researchers, to carefully and respectfully negotiate the requirements of the interview within a relationship they form with participants: being sensitive to the needs of participants and respectful of their wishes - and establishing an ethical relationship.</p
A Terminal Velocity on the Landscape: Particle Production near Extra Species Loci in Higher Dimensions
We investigate particle production near extra species loci (ESL) in a higher
dimensional field space and derive a speed limit in moduli space at weak
coupling. This terminal velocity is set by the characteristic ESL-separation
and the coupling of the extra degrees of freedom to the moduli, but it is
independent of the moduli's potential if the dimensionality of the field space
is considerably larger than the dimensionality of the loci, D >> d. Once the
terminal velocity is approached, particles are produced at a plethora of nearby
ESLs, preventing a further increase in speed via their backreaction. It is
possible to drive inflation at the terminal velocity, providing a
generalization of trapped inflation with attractive features: we find that more
than sixty e-folds of inflation for sub-Planckian excursions in field space are
possible if ESLs are ubiquitous, without fine tuning of initial conditions and
less tuned potentials. We construct a simple, observationally viable model with
a slightly red scalar power-spectrum and suppressed gravitational waves; we
comment on the presence of additional observational signatures originating from
IR-cascading and individual massive particles. We also show that
moduli-trapping at an ESL is suppressed for D >> d, hindering dynamical
selection of high-symmetry vacua on the landscape based on this mechanism.Comment: 46 pages, 6 figures. V3: typos corrected compared to JHEP version,
conclusions unchange
Phosphoenolpyruvate carboxylase dentified as a key enzyme in erythrocytic Plasmodium falciparum carbon metabolism
Phospoenolpyruvate carboxylase (PEPC) is absent from humans but encoded in thePlasmodium falciparum genome, suggesting that PEPC has a parasite-specific function. To investigate its importance in P. falciparum, we generated a pepc null mutant (D10Δpepc), which was only achievable when malate, a reduction product of oxaloacetate, was added to the growth medium. D10Δpepc had a severe growth defect in vitro, which was partially reversed by addition of malate or fumarate, suggesting that pepc may be essential in vivo. Targeted metabolomics using 13C-U-D-glucose and 13C-bicarbonate showed that the conversion of glycolytically-derived PEP into malate, fumarate, aspartate and citrate was abolished in D10Δpepc and that pentose phosphate pathway metabolites and glycerol 3-phosphate were present at increased levels. In contrast, metabolism of the carbon skeleton of 13C,15N-U-glutamine was similar in both parasite lines, although the flux was lower in D10Δpepc; it also confirmed the operation of a complete forward TCA cycle in the wild type parasite. Overall, these data confirm the CO2 fixing activity of PEPC and suggest that it provides metabolites essential for TCA cycle anaplerosis and the maintenance of cytosolic and mitochondrial redox balance. Moreover, these findings imply that PEPC may be an exploitable target for future drug discovery
Moving Stories: Agency, Emotion and Practical Rationality
What is it to be an agent? One influential line of thought, endorsed by G. E. M. Anscombe and David Velleman, among others, holds that agency depends on practical rationality—the ability to act for reasons, rather than being merely moved by causes. Over the past 25 years, Velleman has argued compellingly for a distinctive view of agency and the practical rationality with which he associates it. On Velleman’s conception, being an agent consists in having the capacity to be motivated by a drive to act for reasons. Your bodily movements qualify as genuine actions insofar as they are motivated in part by your desire to behave in a way that makes sense to yourself. However, there are at least two distinct ways of spelling out what this drive towards self-intelligibility consists in, both present in Velleman’s work. It might consist in a drive towards intelligibility in causal-psychological terms: roughly, a drive to maximize the rational coherence of your psychological states. Alternatively, it might consist in a drive towards narrative intelligibility: a drive to make your ongoing activity conform to a recognizable narrative structure, where that structure is understood emotionally. Velleman originally saw these options as basically equivalent, but later came to prioritize the drive towards causal-psychological intelligibility over that towards narrative intelligibility. I argue that this gets things the wrong way round—we should instead understand our capacities to render ourselves intelligible in causal-psychological terms as built upon a bedrock of emotionally suffused narrative understanding. In doing so, we resolve several problems for Velleman’s view, and pave the way for an embodied, embedded and affective account of practical rationality and agency. According to the picture that emerges, practical rationality is essential to agency, narrative understanding is essential to practical rationality, and the rhythms and structures patterning the ebb and flow of our emotional lives are essential to narrative understanding
Improving the uptake of preconception care and periconceptional folate supplementation: what do women think?
<p>Abstract</p> <p>Background</p> <p>Despite strong evidence of the benefits of preconception interventions to improve pregnancy outcomes, the delivery and uptake of preconception care in general and periconceptional folate supplementation in particular remains low. The aim of this study was to determine women's views of the barriers and enablers to the uptake of preconception care and periconceptional folate supplementation.</p> <p>Methods</p> <p>Focus groups were undertaken in 2007 with 17 women of reproductive age (18-45 years). To identify key issues and themes within the data, focus groups were analysed using an inductive process of thematic analysis.</p> <p>Results</p> <p>Most women were unaware of the need to attend for preconception care and were surprised at the breadth of issues involved. Women also felt general practitioners (GPs) should be more proactive in promoting preconception care availability but acknowledged that they themselves had to be thinking about pregnancy or becoming pregnant to be receptive to it. Barriers to periconceptional folate supplementation included confusion about reasons for use, dose, duration, timing and efficacy of folate use. Enablers included the desire to do anything they could to ensure optimum pregnancy outcomes, and promotional material and letters of invitation from their GP to advise them of the availability and the need for preconception care.</p> <p>Conclusion</p> <p>A number of important barriers and enablers exist for women regarding the delivery and uptake of preconception care and periconceptional folate supplementation. It is essential that these patient perspectives are addressed in both the implementation of evidence based clinical practice guidelines and in the systematic design of an intervention to improve preconception care delivery.</p
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