621 research outputs found

    The British antibiotic and silver-impregnated catheters for ventriculoperitoneal shunts multi-centre randomised controlled trial (the BASICS trial): study protocol

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    BACKGROUND: Insertion of a ventriculoperitoneal shunt (VPS) for the treatment of hydrocephalus is one of the most common neurosurgical procedures in the UK, but failures caused by infection occur in approximately 8% of primary cases. VPS infection is associated with considerable morbidity and mortality and its management results in substantial cost to the health service. Antibiotic-impregnated (rifampicin and clindamycin) and silver-impregnated VPS have been developed to reduce infection rates. Whilst there is some evidence showing that such devices may lead to a reduction in VPS infection, there are no randomised controlled trials (RCTs) to support their routine use. METHODS/DESIGN: Overall, 1,200 patients will be recruited from 17 regional neurosurgical units in the UK and Ireland. Patients of any age undergoing insertion of their first VPS are eligible. Patients with previous indwelling VPS, active and on-going cerebrospinal fluid (CSF) or peritoneal infection, multiloculated hydrocephalus requiring multiple VPS or neuroendoscopy, and ventriculoatrial or ventriculopleural shunt planned will be excluded. Patients will be randomised 1:1:1 to either standard silicone (comparator), antibiotic-impregnated, or silver-impregnated VPS. The primary outcome measure is time to VPS infection. Secondary outcome measures include time to VPS failure of any cause, reason for VPS failure (infection, mechanical failure, or patient failure), types of bacterial VPS infection (organism type and antibiotic resistance), and incremental cost per VPS failure averted. DISCUSSION: The British antibiotic and silver-impregnated catheters for ventriculoperitoneal shunts multi-centre randomised controlled trial (the BASICS trial) is the first multi-centre RCT designed to determine whether antibiotic or silver-impregnated VPS reduce early shunt infection compared to standard silicone VPS. The results of this study will be used to inform current neurosurgical practice and may potentially benefit patients undergoing shunt surgery in the future. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number: ISRCTN49474281

    Regulation of the tumour suppressor PDCD4 by miR-499 and miR-21 in oropharyngeal cancers

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    Š 2016 Zhang et al. Background: The rates of oropharyngeal cancers such as tonsil cancers are increasing. The tumour suppressor protein Programmed Cell Death Protein 4 (PDCD4) has been implicated in the development of various human cancers and small RNAs such as microRNAs (miRNAs) can regulate its expression. However the exact regulation of PDCD4 by multiple miRNAs in oropharyngeal squamous cell carcinoma (SCC) is not well understood. Results: Using two independent oropharyngeal SCC cohorts with a focus on the tonsillar region, we identified a miRNA profile differentiating SCC tissue from normal. Both miR-21 and miR-499 were highly expressed in tonsil SCC tissues displaying a loss of PDCD4. Interestingly, expression of the miRNA machinery, Dicer1, Drosha, DDX5 (Dead Box Helicase 5) and DGCR8 (DiGeorge Syndrome Critical Region Gene 8) were all elevated by greater than 2 fold in the tonsil SCC tissue. The 3'UTR of PDCD4 contains three binding-sites for miR-499 and one for miR-21. Using a wild-type and truncated 3'UTR of PDCD4, we demonstrated that the initial suppression of PDCD4 was mediated by miR-21 whilst sustained suppression was mediated by miR-499. Moreover the single miR-21 site was able to elicit the same magnitude of suppression as the three miR-499 sites. Conclusion: This study describes the regulation of PDCD4 specifically in tonsil SCC by miR-499 and miR-21 and has documented the loss of PDCD4 in tonsil SCCs. These findings highlight the complex interplay between miRNAs and tumour suppressor gene regulation and suggest that PDCD4 loss may be an important step in tonsillar carcinogenesis

    The acheulean handaxe : More like a bird's song than a beatles' tune?

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    Š 2016 Wiley Periodicals, Inc. KV is supported by the Netherlands Organization for Scientific Research. MC is supported by the Canada Research Chairs Program, the Social Sciences and Humanities Research of Canada, the Canada Foundation for Innovation, the British Columbia Knowledge Development Fund, and Simon Fraser UniversityPeer reviewedPublisher PD

    Evidence for the existence of powder sub-populations in micronized materials : Aerodynamic size-fractions of aerosolized powders possess distinct physicochemical properties

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    This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Purpose: To investigate the agglomeration behaviour of the fine ( 12.8 Âľm) particle fractions of salmeterol xinafoate (SX) and fluticasone propionate (FP) by isolating aerodynamic size fractions and characterising their physicochemical and re-dispersal properties. Methods: Aerodynamic fractionation was conducted using the Next Generation Impactor (NGI). Re-crystallized control particles, unfractionated and fractionated materials were characterized for particle size, morphology, crystallinity and surface energy. Re-dispersal of the particles was assessed using dry dispersion laser diffraction and NGI analysis. Results: Aerosolized SX and FP particles deposited in the NGI as agglomerates of consistent particle/agglomerate morphology. SX particles depositing on Stages 3 and 5 had higher total surface energy than unfractionated SX, with Stage 5 particles showing the greatest surface energy heterogeneity. FP fractions had comparable surface energy distributions and bulk crystallinity but differences in surface chemistry. SX fractions demonstrated higher bulk disorder than unfractionated and re-crystallized particles. Upon aerosolization, the fractions differed in their intrinsic emission and dispersion into a fine particle fraction (< 5.0 Âľm). Conclusions: Micronized powders consisted of sub-populations of particles displaying distinct physicochemical and powder dispersal properties compared to the unfractionated bulk material. This may have implications for the efficiency of inhaled drug deliveryPeer reviewe

    Influence of Prenatal Arsenic Exposure and Newborn Sex on Global Methylation of Cord Blood DNA

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    Background An emerging body of evidence indicates that early-life arsenic (As) exposure may influence the trajectory of health outcomes later in life. However, the mechanisms underlying these observations are unknown. Objective The objective of this study was to investigate the influence of prenatal As exposure on global methylation of cord blood DNA in a study of mother/newborn pairs in Matlab, Bangladesh. Design Maternal and cord blood DNA were available from a convenience sample of 101 mother/newborn pairs. Measures of As exposure included maternal urinary As (uAs), maternal blood As (mbAs) and cord blood As (cbAs). Several measures of global DNA methylation were assessed, including the [3H]-methyl-incorporation assay and three Pyrosequencing assays: Alu, LINE-1 and LUMA. Results In the total sample, increasing quartiles of maternal uAs were associated with an increase in covariate-adjusted means of newborn global DNA methylation as measured by the [3H]-methyl-incorporation assay (quartile 1 (Q1) and Q2 vs. Q4; p = 0.06 and 0.04, respectively). Sex-specific linear regression analyses, while not reaching significance level of 0.05, indicated that the associations between As exposures and Alu, LINE-1 and LUMA were positive among male newborns (N = 58) but negative among female newborns (N = 43); tests for sex differences were borderline significant for the association of cbAs and mbAs with Alu (p = 0.05 and 0.09, respectively) and for the association between maternal uAs and LINE-1 (p = 0.07). Sex-specific correlations between maternal urinary creatinine and newborn methyl-incorporation, Alu and LINE-1 were also evident (p\u3c0.05). Conclusions These results suggest that prenatal As exposure is associated with global DNA methylation in cord blood DNA, possibly in a sex-specific manner. Arsenic-induced epigenetic modifications in utero may potentially influence disease outcomes later in life. Additional studies are needed to confirm these findings and to examine the persistence of DNA methylation marks over time

    Moxibustion for cephalic version: a feasibility randomised controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Moxibustion (a type of Chinese medicine which involves burning a herb close to the skin) has been used to correct a breech presentation. Evidence of effectiveness and safety from systematic reviews is encouraging although significant heterogeneity has been found among trials. We assessed the feasibility of conducting a randomised controlled trial of moxibustion plus usual care compared with usual care to promote cephalic version in women with a breech presentation, and examined the views of women and health care providers towards implementing a trial within an Australian context.</p> <p>Methods</p> <p>The study was undertaken at a public hospital in Newcastle, New South Wales, Australia. Women at 34-36.5 weeks of gestation with a singleton breech presentation (confirmed by ultrasound), were randomised to moxibustion plus usual care or usual care alone. The intervention was administered over 10 days. Clinical outcomes included cephalic presentation at birth, the need for ECV, mode of birth; perinatal morbidity and mortality, and maternal complications. Feasibility outcomes included: recruitment rate, acceptability, compliance and a sample size for a future study. Interviews were conducted with 19 midwives and obstetricians to examine the acceptability of moxibustion, and views on the trial.</p> <p>Results</p> <p>Twenty women were randomised to the trial. Fifty one percent of women approached accepted randomisation to the trial. A trend towards an increase in cephalic version at delivery (RR 5.0; 95% CI 0.7-35.5) was found for women receiving moxibustion compared with usual care. There was also a trend towards greater success with version following ECV. Two babies were admitted to the neonatal unit from the moxibustion group. Compliance with the moxibustion protocol was acceptable with no reported side effects. Clinicians expressed the need for research to establish the safety and efficacy of moxibustion, and support for the intervention was given to increase women's choices, and explore opportunities to normalise birth. The sample size for a future trial is estimated to be 381 women.</p> <p>Conclusion</p> <p>Our findings should be interpreted with caution as the study was underpowered to detect statistical differences between groups. Acceptance by women and health professionals towards moxibustion suggest further research is warranted.</p> <p>Trial Registration</p> <p>Australia and New Zealand Clinical Trials Register (ANZCTR): <a href="http://www.anzctr.org.au/ACTRN12609000985280.aspx">ACTRN12609000985280</a></p

    Selective and low temperature transition metal intercalation in layered tellurides

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    Layered materials embrace rich intercalation reactions to accommodate high concentrations of foreign species within their structures, and find many applications spanning from energy storage, ion exchange to secondary batteries. Light alkali metals are generally most easily intercalated due to their light mass, high charge/volume ratio and in many cases strong reducing properties. An evolving area of materials chemistry, however, is to capture metals selectively, which is of technological and environmental significance but rather unexplored. Here we show that the layered telluride T2PTe2 (T=Ti, Zr) displays exclusive insertion of transition metals (for example, Cd, Zn) as opposed to alkali cations, with tetrahedral coordination preference to tellurium. Interestingly, the intercalation reactions proceed in solid state and at surprisingly low temperatures (for example, 80?°C for cadmium in Ti2PTe2). The current method of controlling selectivity provides opportunities in the search for new materials for various applications that used to be possible only in a liquid

    Importance of competing risks in the analysis of anti-epileptic drug failure

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    BACKGROUND: Retention time (time to treatment failure) is a commonly used outcome in antiepileptic drug (AED) studies. METHODS: Two datasets are used to demonstrate the issues in a competing risks analysis of AEDs. First, data collection and follow-up considerations are discussed with reference to information from 15 monotherapy trials. Recommendations for improved data collection and cumulative incidence analysis are then illustrated using the SANAD trial dataset. The results are compared to the more common approach using standard survival analysis methods. RESULTS: A non-significant difference in overall treatment failure time between gabapentin and topiramate (logrank test statistic = 0.01, 1 degree of freedom, p-value = 0.91) masked highly significant differences in opposite directions with gabapentin resulting in fewer withdrawals due to side effects (Gray's test statistic = 11.60, 1 degree of freedom, p = 0.0007) but more due to poor seizure control (Gray's test statistic = 14.47, 1 degree of freedom, p-value = 0.0001). The significant difference in overall treatment failure time between lamotrigine and carbamazepine (logrank test statistic = 5.6, 1 degree of freedom, p-value = 0.018) was due entirely to a significant benefit of lamotrigine in terms of side effects (Gray's test statistic = 10.27, 1 degree of freedom, p = 0.001). CONCLUSION: Treatment failure time can be measured reliably but care is needed to collect sufficient information on reasons for drug withdrawal to allow a competing risks analysis. Important differences between the profiles of AEDs may be missed unless appropriate statistical methods are used to fully investigate treatment failure time. Cumulative incidence analysis allows comparison of the probability of failure between two AEDs and is likely to be a more powerful approach than logrank analysis for most comparisons of standard and new anti-epileptic drugs

    Possible mechanisms of host resistance to Haemonchus contortus infection in sheep breeds native to the Canary Islands

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    Haemonchus contortus appears to be the most economically important helminth parasite for small ruminant production in many regions of the world. The two sheep breeds native to the Canary Islands display distinctly different resistant phenotypes under both natural and experimental infections. Canaria Hair Breed (CHB) tends to have significantly lower worm burden and delayed and reduced egg production than the susceptible Canaria Sheep (CS). To understand molecular mechanisms underlying host resistance, we compared the abomasal mucosal transcriptome of the two breeds in response to Haemonchus infection using RNAseq technology. The transcript abundance of 711 and 50 genes were significantly impacted by infection in CHB and CS, respectively (false discovery rate <0.05) while 27 of these genes were significantly affected in both breeds. Likewise, 477 and 16 Gene Ontology (GO) terms were significantly enriched in CHB and CS, respectively (P < 1.0 × 10(−4)). A broad range of mechanisms have evolved in resistant CHB to provide protection against the parasite. Our findings suggest that readily inducible acute inflammatory responses, complement activation, accelerated cell proliferation and subsequent tissue repair, and immunity directed against parasite fecundity all contributed to the development of host resistance to parasitic infection in the resistant breed

    Enhanced relapse prevention for bipolar disorder – ERP trial. A cluster randomised controlled trial to assess the feasibility of training care coordinators to offer enhanced relapse prevention for bipolar disorder

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    BACKGROUND: Bipolar Disorder (BD) is a common and severe form of mental illness characterised by repeated relapses of mania or depression. Pharmacotherapy is the main treatment currently offered, but this has only limited effectiveness. A recent Cochrane review has reported that adding psycho-social interventions that train people to recognise and manage the early warning signs of their relapses is effective in increasing time to recurrence, improving social functioning and in reducing hospitalisations. However, the review also highlights the difficulties in offering these interventions within standard mental health services due to the need for highly trained therapists and extensive input of time. There is a need to explore the potential for developing Early Warning Sign (EWS) interventions in ways that will enhance dissemination. METHODS AND DESIGN: This article describes a cluster-randomised trial to assess the feasibility of training care coordinators (CCs) in community mental health teams (CMHTs) to offer Enhanced Relapse Prevention (ERP) to people with Bipolar Disorder. CMHTs in the North West of England are randomised to either receive training in ERP and to offer this to their clients, or to continue to offer treatment as usual (TAU). The main aims of the study are (1) to determine the acceptability of the intervention, training and outcome measures (2) to assess the feasibility of the design as measured by rates of recruitment, retention, attendance and direct feedback from participants (3) to estimate the design effect of clustering for key outcome variables (4) to estimate the effect size of the impact of the intervention on outcome. In this paper we provide a rationale for the study design, briefly outline the ERP intervention, and describe in detail the study protocol. DISCUSSION: This information will be useful to researchers attempting to carry out similar feasibility assessments of clinical effectiveness trials and in particular cluster randomised controlled trials
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