368 research outputs found
Greenhouse Gas Emissions from Fossil Fuel Fired Power Generation Systems.
Abstract not availableJRC.(IAM)-Institute For Advanced Material
Liquid Mirror Telescopes: A progress report
We review the present status of liquid mirror telescopes. Interferometric
tests of liquid mirrors (the largest one having a diameter of 2.5 meters ) show
excellent optical qualities. The basic technology is now sufficiently reliable
that it can be put to work. Indeed, a handful of liquid mirrors have now been
built that are used for scientific work. A 3.7-m diameter LMT is presently
being built in the new Laval upgraded testing facilities. Construction of the
mirror can be followed on the Web site: http://astrosun.phy.ulaval.ca/lmt/lmt-
home.html. Finally we address the issue of the field accessible to LMTs
equipped with novel optical correctors. Optical design work, and some
exploratory laboratory work, indicate that a single LMT should be able to
access, with excellent images, small regions anywhere inside fields as large as
45 degrees.Comment: To appear in the SPIE conference proceedings 'Optical Telescopes of
Today and Tomorrow', May 29 - June1, Landskrona/Hven, Sweden, Additional info
on LMs at: http://astrosun.phy.ulaval.ca/lmt/lmt-home.htm
Pulmonary embolism in the elderly: a review on clinical, instrumental and laboratory presentation
OBJECTIVE: Diagnosis of pulmonary embolism (PE) remains difficult and is often missed in the elderly due to nonspecific and atypical presentation. Diagnostic algorithms able to rule out PE and validated in young adult patients may have reduced applicability in elderly patients, which increases the number of diagnostic tools use and costs. The aim of the present study was to analyze the reported clinical presentation of PE in patients aged 65 and more. MATERIALS AND METHODS: Prospective and retrospective English language studies dealing with the clinical, instrumental and laboratory aspects of PE in patients more than 65 and published after January 1987 and indexed in MEDLINE using keywords as pulmonary embolism, elderly, old, venous thromboembolism (VTE) in the title, abstract or text, were reviewed. RESULTS: Dyspnea (range 59%-91.5%), tachypnea (46%-74%), tachycardia (29%-76%), and chest pain (26%-57%) represented the most common clinical symptoms and signs. Bed rest was the most frequent risk factor for VTE (15%-67%); deep vein thrombosis was detected in 15%-50% of cases. Sinus tachycardia, right bundle branch block, and ST-T abnormalities were the most frequent ECG findings. Abnormalities of chest X-ray varied (less than 50% in one-half of the studies and more than 70% in the other one-half). Arterial blood gas analysis revealed severe hypoxemia and mild hypocapnia as the main findings. D-Dimer was higher than cut-off in 100% of patients in 75% of studies. Clinical usefulness of D-Dimer measurement decreases with age, although the strategies based on D-Dimer seem to be cost-effective at least until 80 years. CONCLUSION: Despite limitations due to pooling data of heterogeneous studies, our review could contribute to the knowledge of the presentation of PE in the elderly with its diagnostic difficulties. A diagnostic strategy based on reviewed data is proposed
Detailed patient-individual reporting of lymph node involvement in oropharyngeal squamous cell carcinoma with an online interface
Purpose/ObjectiveWhereas the prevalence of lymph node level (LNL) involvement in head & neck squamous cell carcinomas (HNSCC) has been reported, the details of lymphatic progression patterns are insufficiently quantified. In this study, we investigate how the risk of metastases in each LNL depends on the involvement of upstream LNLs, T-category, HPV status and other risk factors.Materials/MethodsWe retrospectively analyzed patients with newly diagnosed oropharyngeal HNSCC treated at a single institution, resulting in a dataset of 287 patients. For all patients, involvement of LNLs I-VII was recorded individually based on available diagnostic modalities (PET, MR, CT, FNA) together with clinicpathological factors. To analyze the dataset, a web-based graphical user interface (GUI) was developed, which allows querying the number of patients with a certain combination of co-involved LNLs and tumor characteristics.ResultsThe full dataset and GUI is part of the publication. Selected findings are: Ipsilateral level IV was involved in 27% of patients with level II and III involvement, but only in 2% of patients with level II but not III involvement. Prevalence of involvement of ipsilateral levels II, III, IV, V was 79%, 34%, 7%, 3% for early T-category patients (T1/T2) and 85%, 50%, 17%, 9% for late T-category (T3/T4), quantifying increasing involvement with T-category. Contralateral levels II, III, IV were involved in 41%, 19%, 4% and 12%, 3%, 2% for tumors for tumors with and without midline extension, respectively. T-stage dependence of LNL involvement was more pronounced in HPV negative than positive tumors, but overall involvement was similar. Ipsilateral level VII was involved in 14% and 6% of patients with primary tumors in the tonsil and the base of tongue, respectively.ConclusionsDetailed quantification of LNL involvement in HNSCC depending on involvement of upstream LNLs and clinicopathological factors may allow for further personalization of CTV-N definition in the future
Protocol for a modelling study to assess the clinical and cost-effectiveness of indefinite anticoagulant therapy for first unprovoked venous thromboembolism.
INTRODUCTION
Deciding whether to stop or extend anticoagulant therapy indefinitely after completing at least 3 months of initial treatment for a first unprovoked venous thromboembolism (VTE) remains a challenge for clinicians, patients and policy makers. Guidelines suggest an indefinite duration of anticoagulant therapy in these patients, yet its benefits, harms and costs have not been formally assessed. The aim of this proposed modelling study is to assess the differences in clinical benefits, harms and costs of stopping versus continuing anticoagulant therapy indefinitely for a first unprovoked VTE.
METHODS AND ANALYSIS
We will develop a probabilistic Markov model, adopting a 1-month cycle length and a lifetime horizon, to estimate life-years, quality-adjusted life-years, costs and the incremental cost-effectiveness ratios for a simulated population of patients with a first unprovoked VTE who will receive indefinite duration of anticoagulant therapy versus a population who will not receive extended treatment after completing 3 months of initial anticoagulant therapy. The economic evaluation will adopt a third-party payer perspective relating to a Canadian publicly funded healthcare system. Estimates for the probability of relevant clinical events will be informed by systematic reviews and meta-analyses, while costs and utility values will be obtained from published Canadian sources. Stratified analyses based on sex, age and site of initial VTE will also be performed to identify subgroups of patients with a first unprovoked VTE in whom continuing anticoagulant therapy indefinitely might prove to be clinically beneficial and cost-effective over stopping treatment. We will also conduct sensitivity and scenario analyses to assess robustness of study findings to changes in individual or groups of key parameters.
ETHICS AND DISSEMINATION
Ethical approval is not applicable for this study. The results will be disseminated through presentations at relevant conferences and in a manuscript that will be submitted to a peer-reviewed journal
Human macrophages release higher IL-1ra over IL-1beta when stimulated by block acetylated chitosan microparticles and not by random acetylated chitosans or water-soluble oligomers
Mapping of transrectal ultrasonographic prostate biopsies: quality control and learning curve assessment by image processing
Objective: Mapping of transrectal ultrasonographic (TRUS) prostate biopsies
is of fundamental importance for either diagnostic purposes or the management
and treatment of prostate cancer, but the localization of the cores seems
inaccurate. Our objective was to evaluate the capacities of an operator to plan
transrectal prostate biopsies under 2-dimensional TRUS guidance using a
registration algorithm to represent the localization of biopsies in a reference
3-dimensional ultrasonographic volume.
Methods: Thirty-two patients underwent a series of 12 prostate biopsies under
local anesthesia performed by 1 operator using a TRUS probe combined with
specific third-party software to verify that the biopsies were indeed conducted
within the planned targets. RESULTS: The operator reached 71% of the planned
targets with substantial variability that depended on their localization (100%
success rate for targets in the middle and right parasagittal parts versus 53%
for targets in the left lateral base). Feedback from this system after each
series of biopsies enabled the operator to significantly improve his dexterity
over the course of time (first 16 patients: median score, 7 of 10 and cumulated
median biopsy length in targets of 90 mm; last 16 patients, median score, 9 of
10 and a cumulated median length of 121 mm; P = .046).
Conclusions: In addition to being a useful tool to improve the distribution
of prostate biopsies, the potential of this system is above all the preparation
of a detailed "map" of each patient showing biopsy zones without substantial
changes in routine clinical practices
Lysosomal rupture induced by structurally distinct chitosans either promotes a type 1 IFN response or activates the inflammasome in macrophages
Chitosan is a family of glucosamine and N-acetyl glucosamine polysaccharides with poorly understood immune modulating properties. Here, functional U937 macrophage responses were analyzed in response to a novel library of twenty chitosans with controlled degree of deacetylation (DDA, 60-98%), molecular weight (1 to >100 kDa), and acetylation pattern (block vs. random). Specific chitosan preparations (10 or 190 kDa 80% block DDA and 3, 5, or 10 kDa 98% DDA) either induced macrophages to release CXCL10 and IL-1ra at 5-50 mug/mL, or activated the inflammasome to release IL-1beta and PGE2 at 50-150 mug/mL. Chitosan induction of these factors required lysosomal acidification. CXCL10 production was preceded by lysosomal rupture as shown by time-dependent co-localization of galectin-3 and chitosan and slowed autophagy flux, and specifically depended on IFN-beta paracrine activity and STAT-2 activation that could be suppressed by PGE2. Chitosan induced a type I IFN paracrine response or inflammasome response depending on the extent of lysosomal rupture and cytosolic foreign body invasion. This study identifies the structural motifs that lead to chitosan-driven cytokine responses in macrophages and indicates that lysosomal rupture is a key mechanism that determines the endogenous release of either IL-1ra or IL-1beta
Phase II study of induction chemotherapy with TPF followed by radioimmunotherapy with Cetuximab and intensity-modulated radiotherapy (IMRT) in combination with a carbon ion boost for locally advanced tumours of the oro-, hypopharynx and larynx - TPF-C-HIT
<p>Abstract</p> <p>Background</p> <p>Long-term locoregional control in locally advanced squamous cell carcinoma of the head and neck (SCCHN) remains challenging. While recent years have seen various approaches to improve outcome by intensification of treatment schedules through introduction of novel induction and combination chemotherapy regimen and altered fractionation regimen, patient tolerance to higher treatment intensities is limited by accompanying side-effects. Combined radioimmunotherapy with cetuximab as well as modern radiotherapy techniques such as intensity-modulated radiotherapy (IMRT) and carbon ion therapy (C12) are able to limit toxicity while maintaining treatment effects. In order to achieve maximum efficacy with yet acceptable toxicity, this sequential phase II trial combines induction chemotherapy with docetaxel, cisplatin, and 5-FU (TPF) followed by radioimmunotherapy with cetuximab as IMRT plus carbon ion boost. We expect this approach to result in increased cure rates with yet manageable accompanying toxicity.</p> <p>Methods/design</p> <p>The TPF-C-HIT trial is a prospective, mono-centric, open-label, non-randomized phase II trial evaluating efficacy and toxicity of the combined treatment with IMRT/carbon ion boost and weekly cetuximab in 50 patients with histologically proven locally advanced SCCHN following TPF induction chemotherapy. Patients receive 24 GyE carbon ions (8 fractions) and 50 Gy IMRT (2.0 Gy/fraction) in combination with weekly cetuximab throughout radiotherapy. Primary endpoint is locoregional control at 12 months, secondary endpoints are disease-free survival, progression-free survival, overall survival, acute and late radiation effects as well as any adverse events of the treatment as well as quality of life (QoL) analyses.</p> <p>Discussion</p> <p>The primary objective of TPF-C-HIT is to evaluate efficacy and toxicity of cetuximab in combination with combined IMRT/carbon ion therapy following TPF induction in locally advanced SCCHN.</p> <p>Trial Registration</p> <p>Clinical Trial Identifier: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01245985">NCT01245985</a> (clinicaltrials.gov)</p> <p>EudraCT number: 2009 - 016489- 10</p
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