Antithrombotic therapy in palliative care

Management of venous thromboembolism (VTE) in patients in advanced cancer can be difficult due to the increased risk of recurrent and extending VTE despite therapeutic anticoagulation, and of bleeding due to or exacerbated by anticoagulation. Currently, best practice is long term administration of low molecular weight heparin (LMWH), but a recurrent VTE and bleeding rate remains, and some patients have contra-indications to anticoagulation. Newer anticoagulants such as oral anti-thrombin agents and biotinylated idrapurinux may have a role in the future.Management of venous thromboembolism (VTE) in patients in advanced cancer can be difficult due to the increased risk of recurrent and extending VTE despite therapeutic anticoagulation, and of bleeding due to or exacerbated by anticoagulation. Currently, best practice is long term administration of low molecular weight heparin (LMWH), but a recurrent VTE and bleeding rate remains, and some patients have contra-indications to anticoagulation. Newer anticoagulants such as oral anti-thrombin agents and biotinylated idrapurinux may have a role in the future

Leczenie przeciwzakrzepowe w opiece paliatywnej

Postępowanie w przypadku choroby zakrzepowo-zatorowej (VTE) u pacjentów z zaawansowaną chorobą nowotworową może być trudne ze względu na zwiększone ryzyko nawracających i szerzących się powikłań zakrzepowo-zatorowych, które występują mimo stosowanego leczenia przeciwkrzepliwego, oraz krwawienia mogącego występować lub nasilać się pod wpływem leków przeciwzakrzepowych. Obecnie najlepszą praktyką jest długotrwałe stosowanie heparyny niskocząsteczkowej (LMWH), ale nadal aktualny jest problem nawrotów VTE i krwawień; ponadto u niektórych pacjentów leczenie przeciwzakrzepowe jest przeciwwskazane. W przyszłości istotne znaczenie mogą mieć nowsze leku przeciwzakrzepowe, takie jak doustne inhibitory trombiny i biotynylowany idraparynuks. Medycyna Paliatywna w Praktyce 2010; 4, 2: 74-8

The range and suitability of outcome measures used in the assessment of palliative treatment for inoperable malignant bowel obstruction: A systematic review

Background: Malignant bowel obstruction, a complication of certain advanced cancers, causes severe symptoms which profoundly affect quality of life. Clinical management remains complex, and outcome assessment is inconsistent.Aim: To identify outcomes evaluating palliative treatment for inoperable malignant bowel obstruction, as part of a four-phase study developing a core outcome set. Design: The review is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA); PROSPERO (ID: CRD42019150648). Eligible studies included at least one subgroup with obstruction below the ligament of Treitz undergoing palliative treatment for inoperable malignant bowel obstruction. Study quality was not assessed because the review does not evaluate efficacy. Data sources: Medline, Embase, the Cochrane Database, CINAHL, PSYCinfo Caresearch, Open Grey and BASE were searched for trials and observational studies in October 2021. Results: A total of 4769 studies were screened, 290 full texts retrieved and 80 (13,898 participants) included in a narrative synthesis; 343 outcomes were extracted verbatim and pooled into 90 unique terms across six domains: physiological, nutrition, life impact, resource use, mortality and survival. Prevalent outcomes included adverse events (78% of studies), survival (54%), symptom control (39%) and mortality (31%). Key individual symptoms assessed were vomiting (41% of studies), nausea (34%) and pain (33%); 19% of studies assessed quality of life. Conclusions: Assessment focuses on survival, complications and overall symptom control. There is a need for definitions of treatment ‘success’ that are meaningful to patients, a more consistent approach to symptom assessment, and greater consideration of how to measure wellbeing in this population

A critical review on modelling formalisms and simulation tools in computational biosystems

Integration of different kinds of biological processes is an ultimate goal for whole-cell modelling. We briefly review modelling formalisms that have been used in Systems Biology and identify the criteria that must be addressed by an integrating framework capable of modelling, analysing and simulating different biological networks. Aware that no formalism can fit all purposes we realize Petri nets as a suitable model for Metabolic Engineering and take a deeper perspective on the role of this formalism as an integrating framework for regulatory and metabolic networks.Research supported by PhD grant SFRH/BD/35215/2007 from the Fundacao para a Ciencia e a Tecnologia (FCT) and the MIT-Portugal program

Analysis of talpid3 and wild-type chicken embryos reveals roles for Hedgehog signalling in development of the limb bud vasculature

Chicken talpid mutant embryos have a wide range of Hedgehog-signalling related defects and it is now known that the talpid gene product encodes a novel protein essential for Hedgehog signalling which is required for both activator and repressor functions of Gli transcription factors (Davey, M.G., Paton, I.R., Yin, Y., Schmidt, M., Bangs, F.K., Morrice, D.R., Gordon-Smith, T., Buxton, P., Stamataki, D., Tanaka, M., Münsterberg, A.E., Briscoe, J., Tickle, C., Burt, D.W. (2006). The chicken talpid gene encodes a novel protein essential for Hedgehog signalling. Genes Dev 20 1365-77). Haemorrhaging, oedema and other severe vascular defects are a central aspect of the talpid phenotype (Ede, D.A. and Kelly, W.A (1964a). Developmental abnormalities in the head region of the talpid mutant fowl. J. Embryol. exp. Morp. 12:161-182) and, as Hedgehog (Hh) signalling has been implicated in every stage of development of the vascular system, the vascular defects seen in talpid are also likely to be attributable to abnormal Hedgehog signalling. Gene expression of members of the VEGF and Angiopoietin families of angiogenic growth factors has been linked to haemorrhaging and oedema and we find widespread expression of VEGF-D, rigf and Ang2a in the talpid limb. Furthermore, ectopic expression of these genes in talpid limbs points to regulation via Gli repression rather than activation. We monitored specification of vessel identity in talpid limb vasculature by examining expression of artery-specific genes, Np1 and EphrinB2, and the vein-specific genes, Np2a and Tie2. We show that there are supernumerary subclavian arteries in talpid limb buds and abnormal expression of an artery-specific gene in the venous submarginal sinus, despite the direction of blood flow being normal. Furthermore, we show that Shh can induce Np1 expression but has no effect on Np2a. Finally, we demonstrate that induction of VEGF and Ang2a expression by Shh in normal limb buds is accompanied by vascular remodelling. Thus Hedgehog signalling has a pivotal role in the cascade of angiogenic events in a growing embryonic organ which is similar to that proposed in tumours

Stomatal responses of Eucalyptus species to elevated CO2 concentration and drought stress

Five species of Eucalyptus (E. grandis, E. urophylla, E. camaldulensis, E. torelliana, and E. phaeotrica), among the ten species most commonly used in large scale plantations, were selected for studies on the effects of elevated CO2 concentration [CO2] and drought stress on stomatal responses of 2.5-month old seedlings. The first three species belong to the subgenus Smphyomyrtus, whereas the fourth species belongs to the subgenus Corymbia and E. phaeotrica is from the subgenus Monocalyptus. Seedlings were grown in four pairs of open-top chambers, arranged to have 2 plants of each species in each chamber, with four replications in each of two CO2 concentrations: 350 ± 30 mumol mol-1 and 700 ± 30 mumol mol-1. After 100 days in the chambers, a series of gas exchange measurements were made. Half the plants in each chamber, one plant per species per chamber, were drought-stressed by withholding irrigation, while the remaining plants continued to be watered daily. Drought stress decreased stomatal conductance, photosynthesis and transpiration rates in all the species. The effect of drought stress on stomatal closure was similar in both [CO2]. The positive effects of elevated [CO2] on photosynthesis and water use efficiency were maintained longer during the stress period than under well-watered conditions. The photosynthetic rate of E. phaeotrica was higher even in the fourth day of the drought stress. Drought stress increased photoinhibition of photosynthesis, as measured by chlorophyll fluorescence, which varied among the species, as well as in relation to [CO2]. The results are in agreement with observed differences in stomatal responses between some eucalyptus species of the subgenera Symphyomyrtus and Monocalyptus

Approximate Bisimulations for Sodium Channel Dynamics

Abstract. This paper shows that, in the context of the Iyer et al. 67-variable cardiac myocycte model (IMW), it is possible to replace the detailed 13-state continuous-time MDP model of the sodium-channel dy-namics, with a much simpler Hodgkin-Huxley (HH)-like two-state sodium-channel model, while only incurring a bounded approximation error. The technical basis for this result is the construction of an approximate bisim-ulation between the HH and IMW channel models, both of which are input-controlled (voltage in this case) continuous-time Markov chains. The construction of the appropriate approximate bisimulation, as well as the overall result regarding the behavior of this modified IMW model, in-volves: (1) The identification of the voltage-dependent parameters of the m and h gates in the HH-type channel, based on the observations of the IMW channel. (2) Proving that the distance between observations of the two channels never exceeds a given error. (3) Exploring the sensitivity of the overall IMW model to the HH-type sodium-channel approximation. Our extensive simulation results experimentally validate our findings, for varying IMW-type input stimuli

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection

A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)