922 resultados para Complemented Subgroups
Resumo:
Socioeconomic status (SES) differences in attitudes towards cancer have been implicated in the differential screening uptake and the timeliness of symptomatic presentation. However, the predominant emphasis of this work has been on cancer fatalism, and many studies focus on specific community subgroups. This study aimed to assess SES differences in positive and negative attitudes towards cancer in UK adults. A population-based sample of UK adults (n=6965, age≥50 years) completed the Awareness and Beliefs about Cancer scale, including six belief items: three positively framed (e.g. 'Cancer can often be cured') and three negatively framed (e.g. 'A cancer diagnosis is a death sentence'). SES was indexed by education. Analyses controlled for sex, ethnicity, marital status, age, self-rated health, and cancer experience. There were few education-level differences for the positive statements, and overall agreement was high (all>90%). In contrast, there were strong differences for negative statements (all Ps<0.001). Among respondents with lower education levels, 57% agreed that 'treatment is worse than cancer', 27% that cancer is 'a death sentence' and 16% 'would not want to know if I have cancer'. Among those with university education, the respective proportions were 34, 17 and 6%. Differences were not explained by cancer experience or health status. In conclusion, positive statements about cancer outcomes attract near-universal agreement. However, this optimistic perspective coexists alongside widespread fears about survival and treatment, especially among less-educated groups. Health education campaigns targeting socioeconomically disadvantaged groups might benefit from a focus on reducing negative attitudes, which is not necessarily achieved by promoting positive attitudes.
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We present early photometric and spectroscopic observations of SN 2013ej, a bright Type IIP supernova (SN) in M74. SN 2013ej is one of the closest SNe ever discovered. The available archive images and the early discovery help to constrain the nature of its progenitor. The earliest detection of this explosion was on 2013 July 24.125 UT and our spectroscopic monitoring with the FLOYDS spectrographs began on July 27.7 UT, continuing almost daily for two weeks. Daily optical photometric monitoringwas achieved with the 1mtelescopes of the Las Cumbres Observatory Global Telescope (LCOGT) network, and was complemented by UV data from Swift and near-infrared spectra from Public ESO Spectroscopic Survey of Transient Objects and Infrared Telescope Facility. The data from our monitoring campaign show that SN 2013ej experienced a 10 d rise before entering into a well-defined plateau phase. This unusually long rise time for a Type IIP has been seen previously in SN 2006bp and SN 2009bw. A relatively rare strong absorption blueward of Hα is present since our earliest spectrum. We identify this feature as Si II, rather than high-velocity Hα as sometimes reported in the literature.
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Following on from the format of the previous Book Understanding Risk: Contributions from the Journal of Risk and Governance, this collection of recent contributions (including work by the editor) this book is divided in three sections . The first section examines issues relating to corporate governance in the private sector, with emphasis being placed on issues of 'Board Decision Making,' Earnings Management and Audit Committee Effectiveness' and ' Corporate Governance Failures.' These contributions are complemented by the second sections which looks at governance and risk issues affecting the public sector, with a focus being places on 'Public Private Partnerships' and regulation of activities in the Life Sciences.' Section three focuses on societal risk management in relation to health, safety and the environment. In this context, contributions are presented in relation to major debates surrounding 'Rising Trends in Cancer Cases,' dilemmas surrounding 'Medical Self Help,' 'Mental Health Policy' and the use of 'Information Technology in Health Care.'
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Fluxes of HCH isomers α- and γ-HCH dynamics were determined in four industrial U.K. rivers feeding the North Sea. Sampling was conducted weekly basis over a 2-year period. This was complemented by discrete studies of events where two hourly sampling periods were used to investigate the fine time scale dynamics of fluxes. Two intensively industrialized rivers had average isomer concentrations of ~20 ng L-1 for both isomers, while average concentrations in the two less industrialized rivers ranged between 1.5 and 5.0 ng L-1. α-HCH concentrations showed no strong temporal patterns on any river, which contrasts with γ-HCH levels that increased considerably during late summer/early autumn following sustained periods of low river flow. Sampling during high river flow events on rivers with differing HCH pollution histories both showed the same dynamics in HCH isomer concentrations. γ-HCH concentrations decreased 4-fold during events while α-HCH-concentrations stayed constant. The increases in γ-HCH concentrations under low flow conditions and the rapid dilution of this isomer during events indicate that γ-HCH has current inputs to these river systems. It was calculated that these four rivers export 30.8 kg yr-1 of γ-HCH and 14.8 kg yr-1 of α-HCH to the North Sea.
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Biodegradation of the model pollutant, 2,4-dichlorophenol (2,4-DCP) by Burkholderia sp. RASC c2, in contaminated soil was assessed by combining chemical analysis with a toxicity test using Escherichia coli HB101 pUCD607. E. coli HB101 pUCD607 was previously marked with luxCDABE genes, encoding bacterial bioluminescence and was used as an alternative to Microtox. Mineralization of 14C-2,4-DCP (196.2 μg g-1 dry wt) in soil occurred rapidly after a 24 h lag. Correspondingly, 2,4-DCP concentrations in soil and soil water extracts decreased with time and concentrations in the latter were at background levels (<0.12 μg mL-1) after day 2. Toxicity of soil water extracts to the lux-based biosensor also decreased with time. Mean light output of E. coli was stimulated by ~1.5 X control values in soil water extracts when concentrations of 2,4-DCP were approaching the limit of detection by HPLC but returned to values equivalent to those of controls when soil water 2,4-DCP concentrations were below the detection limit. No mineralization or microbial growth was detected in noninoculated microcosms. 2,4-DCP concentration in sterile controls decreased significantly with time as did toxicity to E. coli Lux-based E. coli was a sensitive biosensor of 2,4-DCP toxicity during biodegradation and results complemented chemical analysis.
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AIMS: Improved prostate cancer (PCa)-specific biomarkers are urgently required to distinguish between indolent and aggressive disease, in order to avoid overtreatment. In this study, we investigated the prostatic tissue expression of secreted frizzled-related protein (SFRP)-2.
METHODS AND RESULTS: Following immunohistochemical analysis on PCa tissue microarrays with samples from 216 patients, strong/moderate SFRP-2 expression was observed in epithelial cells of benign prostatic hyperplasia, and negative/weak SFRP-2 expression was observed in the majority of tumour epithelia. However, among Gleason grade 5 carcinomas, 40% showed strong/moderate SFRP-2 expression and 60% showed negative SFRP-2 expression in epithelial cells. Further microscopic evaluation of Gleason grade 5 tumours revealed different morphological patterns, corresponding with differential SFRP-2 expression. The first subgroup (referred to as Type A) appeared to have a morphologically solid growth pattern, whereas the second subgroup (referred to as Type B) appeared to have a more diffuse pattern. Furthermore, 100% (4/4) of Type A patients experienced biochemical recurrence, as compared with 0% (0/6) of Type B patients.
CONCLUSIONS: These results imply: (i) that there is a loss of SFRP-2 expression from benign to malignant prostate glands; and (ii) differential SFRP-2 expression among two possible subgroups of Gleason grade 5 tumours.
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Quantile normalization (QN) is a technique for microarray data processing and is the default normalization method in the Robust Multi-array Average (RMA) procedure, which was primarily designed for analysing gene expression data from Affymetrix arrays. Given the abundance of Affymetrix microarrays and the popularity of the RMA method, it is crucially important that the normalization procedure is applied appropriately. In this study we carried out simulation experiments and also analysed real microarray data to investigate the suitability of RMA when it is applied to dataset with different groups of biological samples. From our experiments, we showed that RMA with QN does not preserve the biological signal included in each group, but rather it would mix the signals between the groups. We also showed that the Median Polish method in the summarization step of RMA has similar mixing effect. RMA is one of the most widely used methods in microarray data processing and has been applied to a vast volume of data in biomedical research. The problematic behaviour of this method suggests that previous studies employing RMA could have been misadvised or adversely affected. Therefore we think it is crucially important that the research community recognizes the issue and starts to address it. The two core elements of the RMA method, quantile normalization and Median Polish, both have the undesirable effects of mixing biological signals between different sample groups, which can be detrimental to drawing valid biological conclusions and to any subsequent analyses. Based on the evidence presented here and that in the literature, we recommend exercising caution when using RMA as a method of processing microarray gene expression data, particularly in situations where there are likely to be unknown subgroups of samples.
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We present optical and near-infrared (NIR) photometry and spectroscopy as well as modelling of the lightcurves of the Type IIb supernova (SN) 2011dh. Our extensive dataset, for which we present the observations obtained after day 100, spans two years, and complemented with Spitzer mid-infrared (MIR) data, we use it to build an optical-to-MIR bolometric lightcurve between days 3 and 732. To model the bolometric lightcurve before day 400 we use a grid of hydrodynamical SN models, which allows us to determine the errors in the derived quantities, and a bolometric correction determined with steady-state non-local thermodynamic equilibrium (NLTE) modelling. Using this method we find a helium core mass of 3.1<sup>+0.7</sup><inf>-0.4</inf> M<inf>⊙</inf> for SN 2011dh, consistent within error bars with previous results obtained using the bolometric lightcurve before day 80. We compute bolometric and broad-band lightcurves between days 100 and 500 from spectral steady-state NLTE models, presented and discussed in a companion paper. The preferred 12 M<inf>⊙</inf> (initial mass) model, previously found to agree well with the observed spectra, shows a good overall agreement with the observed lightcurves, although some discrepancies exist. Time-dependent NLTE modelling shows that after day ∼600 a steady-state assumption is no longer valid. The radioactive energy deposition in this phase is likely dominated by the positrons emitted in the decay of <sup>56</sup>Co, but seems insufficient to reproduce the lightcurves, and what energy source is dominating the emitted flux is unclear. We find an excess in the K and the MIR bands developing between days 100 and 250, during which an increase in the optical decline rate is also observed. A local origin of the excess is suggested by the depth of the He I 20 581 Å absorption. Steady-state NLTE models with a modest dust opacity in the core (τ = 0.44), turned on during this period, reproduce the observed behaviour, but an additional excess in the Spitzer 4.5 μm band remains. Carbon-monoxide (CO) first-overtone band emission is detected at day 206, and possibly at day 89, and assuming the additional excess to bedominated by CO fundamental band emission, we find fundamental to first-overtone band ratios considerably higher than observed in SN 1987A. The profiles of the [O i] 6300 Å and Mg i] 4571 Å lines show a remarkable similarity, suggesting that these lines originate from a common nuclear burning zone (O/Ne/Mg), and using small scale fluctuations in the line profiles we estimate a filling factor of ≲ 0.07 for the emitting material. This paper concludes our extensive observational and modelling work on SN 2011dh. The results from hydrodynamical modelling, steady-state NLTE modelling, and stellar evolutionary progenitor analysis are all consistent, and suggest an initial mass of ∼12 M<inf>⊙</inf> for the progenitor.
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Integrins (ITGs) are key elements in cancer biology, regulating tumor growth, angiogenesis and lymphangiogenesis through interactions of the tumor cells with the microenvironment. Moving from the hypothesis that ITGs could have different effects in stage II and III colon cancer, we tested whether a comprehensive panel of germline single-nucleotide polymorphisms (SNPs) in ITG genes could predict stage-specific time to tumor recurrence (TTR). A total of 234 patients treated with 5-fluorouracil-based chemotherapy at the University of Southern California were included in this study. Whole-blood samples were analyzed for germline SNPs in ITG genes using PCR-restriction fragment length polymorphism or direct DNA sequencing. In the multivariable analysis, stage II colon cancer patients with at least one G allele for ITGB3 rs4642 had higher risk of recurrence (hazard ratio (HR)=4.027, 95% confidence interval (95% CI) 1.556-10.421, P=0.004). This association was also significant in the combined stage II-III cohort (HR=1.975, 95% CI 1.194-3.269, P=0.008). The predominant role of ITGB3 rs4642 in stage II diseases was confirmed using recursive partitioning, showing that ITGB3 rs4642 was the most important factor in stage II diseases. In contrast, in stage III diseases the combined analysis of ITGB1 rs2298141 and ITGA4 rs7562325 allowed to identify three distinct prognostic subgroups (P=0.009). The interaction between stage and the combined ITGB1 rs2298141 and ITGA4 rs7562325 on TTR was significant (P=0.025). This study identifies germline polymorphisms in ITG genes as independent stage-specific prognostic markers for stage II and III colon cancer. These data may help to select subgroups of patients who may benefit from ITG-targeted treatments.
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BACKGROUND: Understanding the heterogeneous genotypes and phenotypes of prostate cancer is fundamental to improving the way we treat this disease. As yet, there are no validated descriptions of prostate cancer subgroups derived from integrated genomics linked with clinical outcome.
METHODS: In a study of 482 tumour, benign and germline samples from 259 men with primary prostate cancer, we used integrative analysis of copy number alterations (CNA) and array transcriptomics to identify genomic loci that affect expression levels of mRNA in an expression quantitative trait loci (eQTL) approach, to stratify patients into subgroups that we then associated with future clinical behaviour, and compared with either CNA or transcriptomics alone.
FINDINGS: We identified five separate patient subgroups with distinct genomic alterations and expression profiles based on 100 discriminating genes in our separate discovery and validation sets of 125 and 103 men. These subgroups were able to consistently predict biochemical relapse (p = 0.0017 and p = 0.016 respectively) and were further validated in a third cohort with long-term follow-up (p = 0.027). We show the relative contributions of gene expression and copy number data on phenotype, and demonstrate the improved power gained from integrative analyses. We confirm alterations in six genes previously associated with prostate cancer (MAP3K7, MELK, RCBTB2, ELAC2, TPD52, ZBTB4), and also identify 94 genes not previously linked to prostate cancer progression that would not have been detected using either transcript or copy number data alone. We confirm a number of previously published molecular changes associated with high risk disease, including MYC amplification, and NKX3-1, RB1 and PTEN deletions, as well as over-expression of PCA3 and AMACR, and loss of MSMB in tumour tissue. A subset of the 100 genes outperforms established clinical predictors of poor prognosis (PSA, Gleason score), as well as previously published gene signatures (p = 0.0001). We further show how our molecular profiles can be used for the early detection of aggressive cases in a clinical setting, and inform treatment decisions.
INTERPRETATION: For the first time in prostate cancer this study demonstrates the importance of integrated genomic analyses incorporating both benign and tumour tissue data in identifying molecular alterations leading to the generation of robust gene sets that are predictive of clinical outcome in independent patient cohorts.
Resumo:
Background
Mechanical ventilation is a life-saving intervention for critically ill newborn infants with respiratory failure admitted to a neonatal intensive care unit (NICU). Ventilating newborn infants can be challenging due to small tidal volumes, high breathing frequencies, and the use of uncuffed endotracheal tubes. Mechanical ventilation has several short-term, as well as long-term complications. To prevent complications, weaning from the ventilator is started as soon as possible. Weaning aims to support the transfer from full mechanical ventilation support to spontaneous breathing activity.
Objectives
To assess the efficacy of protocolized versus non-protocolized ventilator weaning for newborn infants in reducing the duration of invasive mechanical ventilation, the duration of weaning, and shortening the NICU and hospital length of stay. To determine efficacy in predefined subgroups including: gestational age and birth weight; type of protocol; and type of protocol delivery. To establish whether protocolized weaning is safe and clinically effective in reducing the duration of mechanical ventilation without increasing the risk of adverse events.
Search methods
We searched the Cochrane Central Register of Controlled trials (CENTRAL; the Cochrane Library; 2015, Issue 7); MEDLINE In-Process and other Non-Indexed Citations and OVID MEDLINE (1950 to 31 July 2015); CINAHL (1982 to 31 July 2015); EMBASE (1988 to 31 July 2015); and Web of Science (1990 to 15 July 2015). We did not restrict language of publication. We contacted authors of studies with a subgroup of newborn infants in their study, and experts in the field regarding this subject. In addition, we searched abstracts from conference proceedings, theses, dissertations, and reference lists of all identified studies for further relevant studies.
Selection criteria
Randomized, quasi-randomized or cluster-randomized controlled trials that compared protocolized with non-protocolized ventilator weaning practices in newborn infants with a gestational age of 24 weeks or more, who were enrolled in the study before the postnatal age of 28 completed days after the expected date of birth.
Data collection and analysis
Four authors, in pairs, independently reviewed titles and abstracts identified by electronic searches. We retrieved full-text versions of potentially relevant studies.
Main results
Our search yielded 1752 records. We removed duplicates (1062) and irrelevant studies (843). We did not find any randomized, quasi-randomized or cluster-randomized controlled trials conducted on weaning from mechanical ventilation in newborn infants. Two randomized controlled trials met the inclusion criteria on type of study and type of intervention, but only included a proportion of newborns. The study authors could not provide data needed for subgroup analysis; we excluded both studies.
Authors' conclusions
Based on the results of this review, there is no evidence to support or refute the superiority or inferiority of weaning by protocol over non-protocol weaning on duration of invasive mechanical ventilation in newborn infants.
Survival of patients with skin melanoma in Europe increases further: Results of the EUROCARE-5 study
Resumo:
Background In Europe skin melanoma (SM) survival has increased over time. The aims were to evaluate recent trends and differences between countries and regions of Europe.
Methods Relative survival (RS) estimates and geographical comparisons were based on 241,485 patients aged 15 years and over with a diagnosis of invasive SM in Europe (2000-2007). Survival time trends during 1999-2007 were estimated using the period approach, for 213,101 patients. Age, gender, sub-sites and morphology subgroups were considered.
Results In European patients, estimated 5-year RS was 83% (95% confidence interval, CI 83-84%). The highest values were found for patients resident in Northern (88%; 87-88%) and Central (88%; 87-88%) Europe, followed by Ireland and United Kingdom (UK) (86%; 85-86%) and Southern Europe (83%; 82-83%). The lowest survival was in Eastern Europe (74%; 74-75%). Within regions the intercountry absolute difference in percentage points of RS varied from 4% (North) to 34% (East). RS decreased markedly with patients' age and was higher in women than men. Differences according to SM morphology and skin sub-sites also emerged. Survival has slightly increased from 1999 to 2007, with a small improvement in Northern and the most pronounced improvement in Eastern Europe.
Discussion SM survival is high and still increasing in European patients. The gap between Northern and Southern and especially Eastern European countries, although still present, diminished over time. Differences in stage distribution at diagnosis may explain most of the geographical differences. However, part of the improvement in survival may be attributed to overdiagnosis from early diagnosis practices.
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The treatment of cancer is becoming more precise, targeting specific oncogenic drivers with targeted molecular therapies. The epidermal growth factor receptor has been found to be over-expressed in a multitude of solid tumours. Immunohistochemistry is widely used in the fields of diagnostic and personalised medicine to localise and visualise disease specific proteins. To date the clinical utility of epidermal growth factor receptor immunohistochemistry in determining monoclonal antibody efficacy has remained somewhat inconclusive. The lack of an agreed reproducible scoring criteria for epidermal growth factor receptor immunohistochemistry has, in various clinical trials yielded conflicting results as to the use of epidermal growth factor receptor immunohistochemistry assay as a companion diagnostic. This has resulted in this test being removed from the licence for the drug panitumumab and not performed in clinical practice for cetuximab. In this review we explore the reasons behind this with a particular emphasis on colorectal cancer, and to suggest a way of resolving the situation through improving the precision of epidermal growth factor receptor immunohistochemistry with quantitative image analysis of digitised images complemented with companion molecular morphological techniques such as in situ hybridisation and section based gene mutation analysis.
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The recent explosion of genetic and clinical data generated from tumor genome analysis presents an unparalleled opportunity to enhance our understanding of cancer, but this opportunity is compromised by the reluctance of many in the scientific community to share datasets and the lack of interoperability between different data platforms. The Global Alliance for Genomics and Health is addressing these barriers and challenges through a cooperative framework that encourages "team science" and responsible data sharing, complemented by the development of a series of application program interfaces that link different data platforms, thus breaking down traditional silos and liberating the data to enable new discoveries and ultimately benefit patients.
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OBJECTIVE: This study validates different definitions of reported night blindness (XN) in a vitamin A deficient African population with no local term for XN. DESIGN: Case-control study with follow-up after treatment. SETTING: Eight primary schools and health centres in rural Tanzania. SUBJECTS: A total of 1214 participants were screened for reported XN and other eye signs of xerophthalmia: 461 children aged 24-71 months, 562 primary school-age children and 191 pregnant or breast-feeding women. All 152 cases of reported XN were selected for the validation study and group matched with 321 controls who did not complain of XN. XN reports were validated against serum retinol concentrations and pupillary dark adaptation measurements in cases and controls. INTERVENTION: All children and women who reported XN or had other signs of active xerophthalmia were treated with vitamin A and followed up 3-4 weeks later. Half of the untreated control group who had their serum retinol examined in the baseline examination were also followed up. RESULTS: The overall prevalence of reported XN was 12.5%. At baseline, mean pupillary threshold (-1.52 vs -1.55 log cd/m(2), P=0.501) and median serum retinol concentrations (0.95 vs 0.93 micromol/l, P=0.734) were not significantly different in cases and controls either overall or in each population group. More restricted case definitions reduced the prevalence of reported XN to 5.5% (P<0.001), but there was still no significant difference between cases and controls although the results were in the expected direction. After treatment, the median serum retinol concentration improved significantly only in the most deficient group, the young children. Dark adaptation improved in all the subgroups but the difference was only significant for young children and primary school-age children when the restricted case definitions were used. CONCLUSIONS: XN reports are a poor indicator of vitamin A deficiency in this population. SPONSORSHIP: Task Force Sight and Life, Basel, Switzerland.