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Search Results: 1 - 10 of 1279 matches for " Katia Donadello "
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suPAR as a prognostic biomarker in sepsis
Katia Donadello, Sabino Scolletta, Cecilia Covajes, Jean-Louis Vincent
BMC Medicine , 2012, DOI: 10.1186/1741-7015-10-2
Abstract: Sepsis is defined as the clinical syndrome resulting from the presence of both infection and a systemic inflammatory response [1]. Sepsis involves the activation of inflammatory and anti-inflammatory mediators, cellular and humoral reactions, and micro- and macro-circulatory alterations. Despite improvements in the management of critically ill patients with serious infections, sepsis is still the leading cause of death in critically ill patients [2]. Early diagnosis of sepsis is vital because rapid, appropriate therapy is associated with improved outcomes [3]. There is, therefore, a need for better techniques to facilitate the diagnosis of sepsis and to monitor its course. Various biomarkers, biological molecules that are characteristic of normal or pathogenic processes and can be easily and objectively measured, have been proposed as being of potential use for sepsis diagnosis, therapeutic guidance, and/or prognostication [4,5], although their exact role remains undefined [3]. The two biomarkers that have been most widely studied and used in patients with sepsis are C-reactive protein (CRP) and procalcitonin (PCT). Levels of both these biomarkers have been demonstrated to be raised in patients with sepsis making them useful diagnostic indicators [6,7]. Importantly, because they lack specificity for sepsis and levels may be raised in other inflammatory diseases, these biomarkers are more useful for ruling out sepsis than for ruling it in, that is, a completely normal value makes a diagnosis of sepsis very unlikely. PCT, in particular, has also been used for therapeutic guidance in patients with various types of infection [7].Recently, the soluble form of the urokinase-type plasminogen activator receptor (suPAR) has attracted scientific interest because it seems to discriminate better than some other biomarkers among patients with different severities of illness [8]. In this narrative review, we discuss the available literature on suPAR in sepsis and provide a descri
Intra-arrest hypothermia during cardiac arrest: a systematic review
Sabino Scolletta, Fabio Taccone, Per Nordberg, Katia Donadello, Jean-Louis Vincent, Maaret Castren
Critical Care , 2012, DOI: 10.1186/cc11235
Abstract: We performed a systematic search of PubMed, EMBASE, CINAHL, the Cochrane Library and Ovid/Medline databases using "arrest" OR "cardiac arrest" OR "heart arrest" AND "hypothermia" OR "therapeutic hypothermia" OR "cooling" as keywords. Only studies using intra-arrest therapeutic hypothermia (IATH) were selected for this review. Three authors independently assessed the validity of included studies and extracted data regarding characteristics of the studied cohort (animal or human) and the main outcomes related to the use of IATH: Mortality, neurological status and cardiac function (particularly, rate of ROSC).A total of 23 animal studies (level of evidence (LOE) 5) and five human studies, including one randomized controlled trial (LOE 1), one retrospective and one prospective controlled study (LOE 3), and two prospective studies without a control group (LOE 4), were identified. IATH improved survival and neurological outcomes when compared to normothermia and/or hypothermia after ROSC. IATH was also associated with improved ROSC rates and with improved cardiac function, including better left ventricular function, and reduced myocardial infarct size, when compared to normothermia.IATH improves survival and neurological outcome when compared to normothermia and/or conventional hypothermia in experimental models of CA. Clinical data on the efficacy of IATH remain limited.Use of mild therapeutic hypothermia, or "targeted temperature management" as recently suggested [1], has been recommended in cardiac arrest (CA) patients since the publication of two randomized clinical trials in 2002, the results of which demonstrated a significant improvement in neurologically intact survival for comatose CA patients presenting with ventricular fibrillation (VF) or ventricular tachycardia (VT) [2,3]. Current guidelines suggest that mild therapeutic hypothermia should also be considered in patients presenting with other rhythms although this has been less well studied [4].Although therap
Microcirculatory alterations: potential mechanisms and implications for therapy
Daniel De Backer, Katia Donadello, Fabio Taccone, Gustavo Ospina-Tascon, Diamantino Salgado, Jean-Louis Vincent
Annals of Intensive Care , 2011, DOI: 10.1186/2110-5820-1-27
Abstract: Sepsis is associated with high mortality. Multiple mechanisms may contribute to sepsis-associated organ dysfunction, which is related to altered tissue perfusion, especially in the early stages, and to direct alterations in cellular metabolism. The importance of rapid correction of perfusion abnormalities has lead to the concept of early goal-directed therapy, which has been shown to improve the outcome of patients with septic shock [1]. However, even when global hemodynamics are optimized, alterations in the microcirculation can still be present and can contribute to perfusion alterations [2]. Indeed, the microcirculation is responsible for fine-tuning tissue perfusion and adapting it to metabolic demand. Experimental and, more recently with development of new techniques that allow direct visualization of the microcirculation [3], clinical evidence indicate that microcirculatory alterations occur in severe sepsis and septic shock and that these alterations may play a role in the development of organ dysfunction. In this review, we will discuss the relevance of these sepsis-associated microcirculatory alterations, the mechanisms involved in their development and potential therapies.Several methods can be used to evaluate microcirculation in septic patients [3]. Two techniques are currently used to evaluate microcirculation at bedside: Sidestream Sark Field imaging technique (SDF) and near infrared spectroscopy (NIRS). SDF is a small handheld microscope that illuminates the field by light reflection from deeper layers. Vessels are visualized as the selected wavelength is absorbed by the hemoglobin contained in the red blood cells.Orthogonal Polarization Spectral imaging technique (OPS) was based on a similar principle but is no longer available. The technique is limited by the fact that it can only be applied on superficial tissues covered by a thin epithelium (mostly the sublingual area) and it requires collaboration or sedation of the patient. In addition, great ca
Effects of changes in arterial pressure on organ perfusion during septic shock
Aurélie Thooft, Rapha?l Favory, Diamantino Salgado, Fabio S Taccone, Katia Donadello, Daniel De Backer, Jacques Creteur, Jean-Louis Vincent
Critical Care , 2011, DOI: 10.1186/cc10462
Abstract: This was a single center, prospective, interventional study conducted in the medico-surgical intensive care unit of a university hospital. Thirteen patients in septic shock for less than 48 hours who required NE administration were included. NE doses were adjusted to obtain MAPs of 65, 75, 85 and (back to) 65 mmHg. In addition to hemodynamic and metabolic variables, we measured thenar muscle oxygen saturation (StO2), using near infrared spectroscopy (NIRS), with serial vaso-occlusive tests (VOTs) on the upper arm. We also evaluated the sublingual microcirculation using sidestream dark field (SDF) imaging in 6 of the patients.Increasing NE dose was associated with an increase in cardiac output (from 6.1 to 6.7 l/min, P<0.05) and mixed venous oxygen saturation (SvO2, from 70.6 to 75.9%, P<0.05). Oxygen consumption (VO2) remained stable, but blood lactate levels decreased. There was a significant increase in the ascending slope of StO2 (from 111 to 177%/min, P<0.05) after VOTs. SDF imaging showed an increase in perfused vessel density (PVD, from 11.0 to 13.2 n/mm, P<0.05) and in microvascular flow index (MFI, from 2.4 to 2.9, P<0.05).In this series of patients with septic shock, increasing MAP above 65 mmHg with NE was associated with increased cardiac output, improved microvascular function, and decreased blood lactate concentrations. The microvascular response varied among patients suggesting that individualization of blood pressure targets may be warranted.Septic shock is characterized by an alteration in tissue perfusion associated with persistent arterial hypotension - generally defined as a systolic arterial pressure of less than 90 mm Hg [1] - despite adequate fluid resuscitation [2]. This leads to organ dysfunction and even death in around 50% of cases [3]. Evaluation of systemic hemodynamic variables can be inadequate to identify tissue perfusion, which is directly influenced by additional microvascular factors. De Backer and colleagues [4] showed that sepsis
Crowd dynamics and conservation laws with non-local constraints
Boris Andreianov,Carlotta Donadello,Massimiliano D. Rosini
Mathematics , 2013,
Abstract: In this paper we model pedestrian flows evacuating a narrow corridor through an exit by a one-dimensional hyperbolic conservation law with a non-local constraint. Existence and stability results for the Cauchy problem with Lipschitz constraint are achieved by a procedure that combines the wave-front tracking algorithm with the operator splitting method. The Riemann problem with piecewise constant constraint is discussed in details, stressing the possible lack of uniqueness, self-similarity and $\Lloc1$-continuity. One explicit example of application is provided.
Initial-boundary value problems for continuity equations with BV coefficients
Gianluca Crippa,Carlotta Donadello,Laura V. Spinolo
Mathematics , 2013,
Abstract: We establish well-posedness of initial-boundary value problems for continuity equations with BV (bounded total variation) coefficients. We do not prescribe any condition on the orientation of the coefficients at the boundary of the domain. We also discuss some examples showing that, regardless the orientation of the coefficients at the boundary, uniqueness may be violated as soon as the BV regularity deteriorates at the boundary.
The Electronic Eyes of the Social Capital
Valdecir Pereira Uveda,Graciane Donadello,Francieli Montanari Gasparin,Janaina Macke
Signal Processing : An International Journal , 2011,
Abstract: The video camera symbolizes an intelligible system that seeks to replace mechanically thehuman eye, in this paper, entitled “electronic eyes”. People’s reaction when realize that they arebeing observed through the lens of the “electronic eye” are in a variety of ways. Some people getshy, others show themselves off spontaneously, and many of them try to avoid the electroniclens. Can a mechanical eye influence people's behavior? This article examines not only thisissue, but it goes further. Considering the increasing number of cameras installed in public andprivate places, the question is: may this fact cause any change in social relationships? The mainpurpose of this paper is to analyze the electronic eye’s influence on the concept of social capital.A qualitative exploratory study was performed conducted by semi-structured interviews. Theresults show that the electronic eye influences on peoples’ idea, on the social relationships, andon the social capital concept. Although changing peoples’ behavior and attitudes, the electroniceye does not replace the human eye, it only complements it. Coined by the authors, the term“electronic eyes”, is a contribution of this study to the Social Capital, conceptually supported bythe social philosophy.
Spontaneous creation of Kibble-Zurek solitons in a Bose-Einstein condensate
Giacomo Lamporesi,Simone Donadello,Simone Serafini,Franco Dalfovo,Gabriele Ferrari
Physics , 2013, DOI: 10.1038/nphys2734
Abstract: When a system crosses a second-order phase transition on a finite timescale, spontaneous symmetry breaking can cause the development of domains with independent order parameters, which then grow and approach each other creating boundary defects. This is known as Kibble-Zurek mechanism. Originally introduced in cosmology, it applies both to classical and quantum phase transitions, in a wide variety of physical systems. Here we report on the spontaneous creation of solitons in Bose-Einstein condensates via the Kibble-Zurek mechanism. We measure the power-law dependence of defects number with the quench time, and provide a check of the Kibble-Zurek scaling with the sonic horizon. These results provide a promising test bed for the determination of critical exponents in Bose-Einstein condensates.
A compact high-flux source of cold sodium atoms
G. Lamporesi,S. Donadello,S. Serafini,G. Ferrari
Physics , 2013, DOI: 10.1063/1.4808375
Abstract: We present a compact source of cold sodium atoms suitable for the production of quantum degenerate gases and versatile for a multi-species experiment. The magnetic field produced by permanent magnets allows to simultaneously realize a Zeeman slower and a two-dimensional MOT within an order of magnitude smaller length than standard sodium sources. We achieve an atomic flux exceeding 4x10^9 atoms/s loaded in a MOT, with a most probable longitudinal velocity of 20 m/s, and a brightness larger than 2.5x10^(12) atoms/s/sr. This atomic source allowed us to produce a pure BEC with more than 10^7 atoms and a background pressure limited lifetime of 5 minutes.
Riemann problems with non--local point constraints and capacity drop
Boris Andreianov,Carlotta Donadello,Ulrich Razafison,Massimiliano D. Rosini
Mathematics , 2014,
Abstract: In the present note we discuss in details the Riemann problem for a one--dimensional hyperbolic conservation law subject to a point constraint. We investigate how the regularity of the constraint operator impacts the well--posedness of the problem, namely in the case, relevant for numerical applications, of a discretized exit capacity. We devote particular attention to the case in which the constraint is given by a non--local operator depending on the solution itself. We provide several explicit examples. We also give the detailed proof of some results announced in the paper [Andreainov, Donadello, Rosini, "Crowd dynamics and conservation laws with non--local point constraints and capacity drop", which is devoted to existence and stability for a more general class of Cauchy problems subject to Lipschitz continuous non--local point constraints.
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