4 resultados para 677.02
em AMS Tesi di Dottorato - Alm@DL - Università di Bologna
Resumo:
INTRODUCTION: A relationship between inflammatory response and coagulation is suggested by many observations. In particular, pro-inflammatory cytokines, such as TNFalpha, promote the activation of coagulation and reduce the production of anticoagulant molecules. It is known that inflammatory bowel diseases show a prothrombotic state and a condition of hypercoagulability. Aim of our study was to evaluate whether anti-TNFalpha therapy induces changes in the levels of coagulation activation markers in IBD patients. MATERIALS AND METHODS: We analyzed 48 plasma samples obtained before and 1 hour after 24 infliximab infusions (5 mg/kg) in 9 IBD patients (5 men and 4 women; mean age: 47.6+17.6 years; 4 Crohn's disease, 4 Ulcerative Colitis,1 Indeterminate Colitis). F1+2 and D-dymer levels were measured in each sample using ELISA methods.The data were statistically analyzed by means of Wilcoxon matched paired test. RESULTS: Median F1+2 levels were markdely reduced 1 hour after anti-TNFα infusion (median pre-infusion levels were 247.0 pmol/L and median post-infusion levels were 185.3 pmol/L) (p<0.002). Median D-dymer levels were also significantly reduced, from 485.2 ng/mL to 427.6 ng/mL (p< 0.001). These modifications were more evident in patients naive for infliximab therapy (p<0.02 for F1+2 and p<0.02 for D-dymer) and in Crohn's disease compared with Ulcerative Colitis patients (p=0.01 for F1+2 and p<0.007 for D-dymer).CONCLUSIONS: Infusion of infliximab significantly reduces the activation of coagulation cascade in IBD patients. This effect is early enough to suggest a direct effect of infliximab on the coagulation cascade and a possible new anti-inflammatory mechanism of action of this molecule.
Resumo:
AMS-02 is running after great scientific goals since one year and a half: a final setting up for dark matter searches has been achieved, allowing to study the so important antiparticle to particle ratios, which will probably be the first dark matter signals ever corroborated. Even if primary cosmic rays fluxes are subjected to a lot of uncertainties sources, some statements can be done and have been written down about dark matter properties: DM should be a heavy Majorana fermion or Spin 0 or 1 boson, with a mass from about 1 TeV to 10 TeV - unveiling a new TeV-ish search age - which could be able to originate antiparticle fluxes enhancements at high energies, both for positrons and antiprotons. All the observations, direct and indirect, point to these new paradigms or can be traced back to them quite easily. These enhancements perfectly fall into the research window of AMS-02, allowing the experiment to attack each today credible theory. Also an investigation of the Sommerfeld effect-associated dark boson will be possible, in terms of antiparticle to particle ratios substructures. The first great AMS-02 measurement is the positron fraction: an official paper is going to be submitted in few months, where the correct behavior of the apparatus will be reviewed and the full positron fraction rate will be analyzed up to 200 GeV. In this concern, one of the objectives of this work is to test the AMS-02 capability and versatility in doing these dark matter researches, thanks to an orbital temporal (and geomagnetic) stability. The goal has been accomplished: the experiment is very stable in time, so that the temporal error associated to the positron fraction measurement is compatible with zero, offering a beyond belief opportunity to measure CR antiparticle to particle ratios.