340 research outputs found

    Identification and survival outcomes of a cohort of patients with cancer of unknown primary in Ontario, Canada.

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    BACKGROUND: Cancer of unknown primary origin (CUP) is defined by the presence of pathologically identified metastatic disease without clinical or radiological evidence of a primary tumour. Our objective was to identify incident cases of CUP in Ontario, Canada, and determine the influence of histology and sites of metastases on overall survival (OS). MATERIAL AND METHODS: We used the Ontario Cancer Registry (OCR) and the Same-Day Surgery and Discharge Abstract Database (SDS/DAD) to identify patients diagnosed with CUP in Ontario between 1 January 2000, and 31 December 2005. Patient diagnostic information, including histology and survival data, was obtained from the OCR. We cross-validated CUP diagnosis and obtained additional information about metastasis through data linkage with the SDS/DAD database. OS was assessed using Cox regression models adjusting for histology and sites of metastases. RESULTS: We identified 3564 patients diagnosed with CUP. Patients without histologically confirmed disease (n = 1821) had a one-year OS of 10.9%, whereas patients with confirmed histology (n = 1743) had a one-year OS of 15.6%. The most common metastatic sites were in the respiratory or digestive systems (n = 1603), and the most common histology was adenocarcinoma (n = 939). Three-year survival rates were 3.5%, 5.3%, 41.6% and 3.6% among adenocarcinoma, unspecified carcinoma, squamous cell carcinoma and undifferentiated histology, respectively. Three-year survival rates were 40%, 2.4%, 8.0% and 4.6% among patients with metastases localised to lymph nodes, the respiratory or digestive systems, other specified sites, and unspecified sites, respectively. CONCLUSION: CUP patients in Ontario have a poor prognosis. Some subgroups may have better survival rates, such as patients with metastases localised to lymph nodes and patients with squamous cell histology

    Cost-effectiveness of using a gene expression profiling test to aid in identifying the primary tumour in patients with cancer of unknown primary.

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    We aimed to investigate the cost-effectiveness of a 2000-gene-expression profiling (GEP) test to help identify the primary tumor site when clinicopathological diagnostic evaluation was inconclusive in patients with cancer of unknown primary (CUP). We built a decision-analytic-model to project the lifetime clinical and economic consequences of different clinical management strategies for CUP. The model was parameterized using follow-up data from the Manitoba Cancer Registry, cost data from Manitoba Health administrative databases and secondary sources. The 2000-GEP-based strategy compared to current clinical practice resulted in an incremental cost-effectiveness ratio (ICER) of 44,151perqualityadjustedlifeyears(QALY)gained.Thetotalannualbudgetimpactwas44,151 per quality-adjusted life years (QALY) gained. The total annual-budget impact was 36.2 million per year. A value-of-information analysis revealed that the expected value of perfect information about the test\u27s clinical impact was $4.2 million per year. The 2000-GEP test should be considered for adoption in CUP. Field evaluations of the test are associated with a large societal benefit.The Pharmacogenomics Journal advance online publication, 29 March 2016; doi:10.1038/tpj.2015.94

    Anomalous Aharonov--Bohm gap oscillations in carbon nanotubes

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    The gap oscillations caused by a magnetic flux penetrating a carbon nanotube represent one of the most spectacular observation of the Aharonov-Bohm effect at the nano--scale. Our understanding of this effect is, however, based on the assumption that the electrons are strictly confined on the tube surface, on trajectories that are not modified by curvature effects. Using an ab-initio approach based on Density Functional Theory we show that this assumption fails at the nano-scale inducing important corrections to the physics of the Aharonov-Bohm effect. Curvature effects and electronic density spilled out of the nanotube surface are shown to break the periodicity of the gap oscillations. We predict the key phenomenological features of this anomalous Aharonov-Bohm effect in semi-conductive and metallic tubes and the existence of a large metallic phase in the low flux regime of Multi-walled nanotubes, also suggesting possible experiments to validate our results.Comment: 7 figure

    The clinical significance of occult gastrointestinal primary tumours in metastatic cancer: A population retrospective cohort study

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    © 2018 by the Korean Cancer Association. Purpose The purpose of this study was to estimate the incidence of occult gastrointestinal (GI) primary tumours in patients with metastatic cancer of uncertain primary origin and evaluate their influence on treatments and overall survival (OS). Materials and Methods We used population heath data from Manitoba, Canada to identify all patients initially diagnosed with metastatic cancer between 2002 and 2011. We defined patients to have occult primary tumour if the primary was found at least 6 months after initial diagnosis. Otherwise, we considered primary tumours as obvious. We used propensity-score methods to match each patient with occult GI tumour to four patients with obvious GI tumour on all known clinicopathologic features. We compared treatments and 2-year survival data between the two patient groups and assessed treatment effect on OS using Cox regression adjustment. Results Eighty-three patients had occult GI primary tumours, accounting for 17.6% of men and 14% of women with metastatic cancer of uncertain primary. A 1:4 matching created a matched group of 332 patients with obvious GI primary tumour. Occult cases compared to the matched group were less likely to receive surgical interventions and targeted biological therapy, and more likely to receive cytotoxic empiric chemotherapeutic agents. Having an occult GI tumour was associated with reduced OS and appeared to be a nonsignificant independent predictor of OS when adjusting for treatment differences. Conclusion GI tumours are the most common occult primary tumours in men and the second most common in women. Patients with occult GI primary tumours are potentially being undertreated with available GI site-specific and targeted therapies

    Antibacterial and cytotoxic activities of naphthoquinone pigments from Onosma visianii Clem

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    In this study, the antibacterial and cytotoxic activities of isolated compounds from the roots of Onosma visianii were investigated. By using different chromatographic techniques and appropriate spectroscopic methods, the seven naphthoquinones were described: deoxyshikonin (1), isobutyrylshikonin (2), α-methylbutyrylshikonin (3), acetylshikonin (4), ß-hydroxyisovalerylshikonin (5), 5,8-O-dimethyl isobutyrylshikonin (6) and 5,8-O-dimethyl deoxyshikonin (7). Among the tested compounds, 3 and 4 exhibited the highest antibacterial activities toward all tested bacterial species (MIC50 and MIC90 for gram positive bacteria: 6.40 µg/mL-12.79 µg/mL and 6.82 µg/mL-13.60 µg/mL, respectively; for gram negative bacteria: 4.27 µg/mL-8.53 µg/mL and 4.77 µg/mL-9.54 µg/mL, respectively). Also, naphthoquinones 3 and 4 exhibited strong cytotoxic activity against MDA-MB-231 cells (IC50 values 86.0 µg/mL and 80.2 µg/mL, respectively), while compounds 1, 3, 4 and 5 significantly decreased viability of HCT116 cells (IC50 values of 97.8 µg/mL, 15.2 µg/mL, 24.6 µg/mL and 30.9 µg/mL, respectively). Our results indicated that all tested naphthoquinone pigments are potential candidates for clinical uses as antibacterial and cytotoxic agents

    Anomalous Optoelectronic Properties of Chiral Carbon Nanorings...and One Ring to Rule Them All

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    Carbon nanorings are hoop-shaped, {\pi}-conjugated macrocycles which form the fundamental annular segments of single-walled carbon nanotubes (SWNTs). In a very recent report, the structures of chiral carbon nanorings (which may serve as chemical templates for synthesizing chiral nanotubes) were experimentally synthesized and characterized for the first time. Here, in our communication, we show that the excited-state properties of these unique chiral nanorings exhibit anomalous and extremely interesting optoelectronic properties, with excitation energies growing larger as a function of size (in contradiction with typical quantum confinement effects). While the first electronic excitation in armchair nanorings is forbidden with a weak oscillator strength, we find that the same excitation in chiral nanorings is allowed due to a strong geometric symmetry breaking. Most importantly, among all the possible nanorings synthesized in this fashion, we show that only one ring, corresponding to a SWNT with chiral indices (n+3,n+1), is extremely special with large photoinduced transitions that are most readily observable in spectroscopic experiments.Comment: Accepted by the Journal of Physical Chemistry Letter

    Simulation of an SEIR infectious disease model on the dynamic contact network of conference attendees

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    The spread of infectious diseases crucially depends on the pattern of contacts among individuals. Knowledge of these patterns is thus essential to inform models and computational efforts. Few empirical studies are however available that provide estimates of the number and duration of contacts among social groups. Moreover, their space and time resolution are limited, so that data is not explicit at the person-to-person level, and the dynamical aspect of the contacts is disregarded. Here, we want to assess the role of data-driven dynamic contact patterns among individuals, and in particular of their temporal aspects, in shaping the spread of a simulated epidemic in the population. We consider high resolution data of face-to-face interactions between the attendees of a conference, obtained from the deployment of an infrastructure based on Radio Frequency Identification (RFID) devices that assess mutual face-to-face proximity. The spread of epidemics along these interactions is simulated through an SEIR model, using both the dynamical network of contacts defined by the collected data, and two aggregated versions of such network, in order to assess the role of the data temporal aspects. We show that, on the timescales considered, an aggregated network taking into account the daily duration of contacts is a good approximation to the full resolution network, whereas a homogeneous representation which retains only the topology of the contact network fails in reproducing the size of the epidemic. These results have important implications in understanding the level of detail needed to correctly inform computational models for the study and management of real epidemics

    Electron Transport in Very Clean, As-Grown Suspended Carbon Nanotubes

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    Single walled carbon nanotubes (SWNT) have displayed a wealth of quantum transport phenomena thus far. Defect free, unperturbed SWNTs with wellbehaved or tunable metal contacts are important to probing the intrinsic electrical properties of nanotubes. Meeting these conditions experimentally is nontrivial due to numerous disorder and randomizing factors. Here we show that ~ 1 um long fully suspended SWNTs grown-in-place between metal contacts afford SWNT devices exhibiting well-defined characteristics over much wider energy ranges than nanotubes pinned on substrates. Various low temperature transport regimes in true-metallic, small and large bandgap semiconducting nanotubes are observed including quantum states shell-filling, -splitting and -crossing in magnetic fields for medium conductance devices. The clean transport data reveals a correlation between the contact junction resistance and the various transport regimes in SWNT devices. Further, we show that electrical transport data can be used to probe the band structures of nanotubes including nonlinear band dispersion.Comment: Nature Materials, in pres

    The Implementation of Managed Entry Agreements in Central and Eastern Europe : Findings and Implications

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    Funding Information: In Bosnia and Herzegovina, both The Federation of Bosnia and Herzegovina and the Republic of Srpska, also have special funds and budgets in place for the financing of expensive medicines, which are innovative and under patent. Similar earmarked funds are available in Scotland (the New Medicines Fund funded by the Pharmaceutical Price Regulation Scheme [PPRS] rebates) [35] and England (the Cancer Drugs Fund) [36]. However, support for such earmarked funds is mixed. While they facilitate access, critics raised issues about fairness towards other disease areas and patient groups that are not eligible for special funding [3, 39]. Further, the views of a Patient and Clinician Engagement meeting in Scotland [37] and the end-of-life criteria in England [38] offer opportunities for special considerations affecting medicines for end-of-life and very rare conditions to be taken into account in the health technology assessment process. Funding Information: The authors would like to acknowledge Dr. Jan Jones from the Scottish Medicines Consortium, Scotland, for contributing to the discussion with information on Scotland, Drs. Lyudmila Bezmelnitsyna and Anastasia Isaeva for contributing to data collection in Russia and Dr. Kate?ina Podrazilov? from SZP ?R for providing information on the Czech Republic. Alessandra Ferrario was a Research Officer at the LSE Health at the time this research was conducted. She is now a postdoctoral Research Fellow at the Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, USA. Email: [email protected] No sources of funding were used for this study. The authors declare they have no conflicts of interest. However, Di?na Ar?ja, Maria Dimitrova, Jurij F?rst, Ieva Grei?i?t?-Kuprijanov, Iris Hoxha, Arianit Jakupi, Erki Laidm?e, Vanda Markovic-Pekovic, Dmitry Meshkov, Guenka Petrova, Maciej Pomorski and Patricia Vella Bonanno work directly for national health authorities or are advisers to them. Alessandra Ferrario, Tomasz Bochenek, Ileana Mardare, Dominik Tomek, Luka Voncina, Alan Haycox, Panos Kanavos,?Olga L?blov?, and Brian Godman are academics and independent researchers also working with national and regional health authorities and others to improve the quality and efficiency of prescribing, and Tarik Catic, D?vid Dank?,and Tanja Novakovic are involved with pharmaceutical, pharmacoeconomics and outcomes research groups in their countries. Olga L?blov? has also carried out remunerated consultancy activities for A&R Partners, Baxter AG and Instytut Arcana and Ileana Mardare has signed a consulting contract with Ewopharma A.G. Romania. The content of the paper and the conclusions are those of each author and may not necessarily reflect those of any organisation that employs them. Publisher Copyright: © 2017, The Author(s).Background: Managed entry agreements (MEAs) are a set of instruments to facilitate access to new medicines. This study surveyed the implementation of MEAs in Central and Eastern Europe (CEE) where limited comparative information is currently available. Method: We conducted a survey on the implementation of MEAs in CEE between January and March 2017. Results: Sixteen countries participated in this study. Across five countries with available data on the number of different MEA instruments implemented, the most common MEAs implemented were confidential discounts (n = 495, 73%), followed by paybacks (n = 92, 14%), price-volume agreements (n = 37, 5%), free doses (n = 25, 4%), bundle and other agreements (n = 19, 3%), and payment by result (n = 10, >1%). Across seven countries with data on MEAs by therapeutic group, the highest number of brand names associated with one or more MEA instruments belonged to the Anatomical Therapeutic Chemical (ATC)-L group, antineoplastic and immunomodulating agents (n = 201, 31%). The second most frequent therapeutic group for MEA implementation was ATC-A, alimentary tract and metabolism (n = 87, 13%), followed by medicines for neurological conditions (n = 83, 13%). Conclusions: Experience in implementing MEAs varied substantially across the region and there is considerable scope for greater transparency, sharing experiences and mutual learning. European citizens, authorities and industry should ask themselves whether, within publicly funded health systems, confidential discounts can still be tolerated, particularly when it is not clear which country and party they are really benefiting. Furthermore, if MEAs are to improve access, countries should establish clear objectives for their implementation and a monitoring framework to measure their performance, as well as the burden of implementation.publishersversionPeer reviewe
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