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Rossetto V, Moore-Machacek A, Woods DF, Galvão HM, Shanahan RM, Hickey A, O'Leary N, O'Gara F, McGlacken GP, Reen FJ. Structural modification of the Pseudomonas aeruginosa alkylquinoline cell-cell communication signal, HHQ, leads to benzofuranoquinolines with anti-virulence behaviour in ESKAPE pathogens. Microbiology (Reading) 2023; 169. [PMID: 36862576 DOI: 10.1099/mic.0.001303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Microbial populations have evolved intricate networks of negotiation and communication through which they can coexist in natural and host ecosystems. The nature of these systems can be complex and they are, for the most part, poorly understood at the polymicrobial level. The Pseudomonas Quinolone Signal (PQS) and its precursor 4-hydroxy-2-heptylquinoline (HHQ) are signal molecules produced by the important nosocomial pathogen
Pseudomonas aeruginosa
. They are known to modulate the behaviour of co-colonizing bacterial and fungal pathogens such as Bacillus atropheaus, Candida albicans and Aspergillus fumigatus. While the structural basis for alkyl-quinolone signalling within
P. aeruginosa
has been studied extensively, less is known about how structural derivatives of these molecules can influence multicellular behaviour and population-level decision-making in other co-colonizing organisms. In this study, we investigated a suite of small molecules derived initially from the HHQ framework, for anti-virulence activity against ESKAPE pathogens, at the species and strain levels. Somewhat surprisingly, with appropriate substitution, loss of the alkyl chain (present in HHQ and PQS) did not result in a loss of activity, presenting a more easily accessible synthetic framework for investigation. Virulence profiling uncovered significant levels of inter-strain variation among the responses of clinical and environmental isolates to small-molecule challenge. While several lead compounds were identified in this study, further work is needed to appreciate the extent of strain-level tolerance to small-molecule anti-infectives among pathogenic organisms.
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Affiliation(s)
- Veronica Rossetto
- Faculty of Science and Technology, Universidade do Algarve, Algarve, Portugal.,School of Microbiology, University College Cork, Cork, Ireland
| | | | - David F Woods
- School of Microbiology, University College Cork, Cork, Ireland
| | - Helena M Galvão
- Faculty of Science and Technology, Universidade do Algarve, Algarve, Portugal
| | - Rachel M Shanahan
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Aobha Hickey
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland
| | - Niall O'Leary
- School of Microbiology, University College Cork, Cork, Ireland
| | - Fergal O'Gara
- School of Microbiology, University College Cork, Cork, Ireland.,Biomerit Research Centre, School of Microbiology, University College Cork, Cork, Ireland.,Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth, WA, Australia
| | - Gerard P McGlacken
- School of Chemistry and Analytical and Biological Chemistry Research Facility, University College Cork, Cork, Ireland.,Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland
| | - F Jerry Reen
- School of Microbiology, University College Cork, Cork, Ireland.,Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland
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2
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Mulinari J, Venturin B, Sbardelotto M, Dall Agnol A, Scapini T, Camargo AF, Baldissarelli DP, Modkovski TA, Rossetto V, Dalla Rosa C, Reichert FW, Golunski SM, Vieitez I, Vargas GDLP, Dalla Rosa C, Mossi AJ, Treichel H. Ultrasound-assisted hydrolysis of waste cooking oil catalyzed by homemade lipases. Ultrason Sonochem 2017; 35:313-318. [PMID: 27746067 DOI: 10.1016/j.ultsonch.2016.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 10/07/2016] [Accepted: 10/07/2016] [Indexed: 06/06/2023]
Abstract
This study aimed to evaluate the waste cooking oil (WCO) hydrolysis in ultrasonic system using lipase as catalyst. Lipase was produced by the fungus Aspergillus niger via solid state fermentation (SSF) using canola meal as substrate. Prior to the hydrolysis reaction, the lipase behavior when subjected to ultrasound was evaluated by varying the temperature of the ultrasonic bath, the exposure time and the equipment power. Having optimized the treatment on ultrasound, the WCO hydrolysis reaction was carried out by evaluating the oil:water ratio and the lipase concentration. For a greater homogenization of the reaction medium, a mechanical stirrer at 170rpm was used. All steps were analyzed by experimental design technique. The lipase treatment in ultrasound generated an increase of about 320% in its hydrolytic activity using 50% of ultrasonic power for 25min. at 45°C. The results of the experimental design conducted for ultrasound-assisted hydrolysis showed that the best condition was using an oil:water ratio of 1:3 (v:v) and enzyme concentration of 15% (v/v), generating 62.67μmol/mL of free fatty acids (FFA) in 12h of reaction. Thus, the use of Aspergillus niger lipase as a catalyst for hydrolysis reaction of WCO can be considered as a possible pretreatment technique of the oil in order to accelerate its degradation.
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Affiliation(s)
- J Mulinari
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - B Venturin
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - M Sbardelotto
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - A Dall Agnol
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - T Scapini
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - A F Camargo
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - D P Baldissarelli
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - T A Modkovski
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - V Rossetto
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - C Dalla Rosa
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - F W Reichert
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - S M Golunski
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - I Vieitez
- Grupo de Derivados de la Industria Alimentaria, Departamento de Ciencia y Tecnología de Alimentos (CYTAL), Facultad de Química, Universidad de la República (UdelaR), Montevideo, Uruguay
| | - G D L P Vargas
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - C Dalla Rosa
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - A J Mossi
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil
| | - H Treichel
- Environmental Science and Technology, Federal University of Fronteira Sul - Campus Erechim, RS 135, Km 72, 99700-000 Erechim, RS, Brazil.
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Rossetto V, Barbar S, Vedovetto V, Milan M, Prandoni P. Physicians' compliance with the Padua Prediction Score for preventing venous thromboembolism among hospitalized medical patients. J Thromb Haemost 2013; 11:1428-30. [PMID: 23601653 DOI: 10.1111/jth.12258] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Indexed: 11/28/2022]
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Rossetto V, Spiezia L, Senzolo M, Rodriguez K, Gavasso S, Woodhams B, Simioni P. Factor VIIa-antithrombin complexes in patients with non-neoplastic portal vein thrombosis with and without cirrhosis. Int J Lab Hematol 2012; 35:101-5. [PMID: 22958499 DOI: 10.1111/ijlh.12003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 07/23/2012] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Portal vein thrombosis (PVT) is caused by local and systemic prothrombotic risk factors. In this case-control study, we evaluated the use of the Factor VIIa-antithrombin complex (FVIIa-AT) complex assay as a hypercoagulability marker in patients with PVT. METHODS Two different groups of cases were considered: (i) n = 12 noncirrhotic PVT patients, (ii) n = 33 cirrhotic patients with PVT. Controls were sex and age-matched healthy volunteers and cirrhotic subjects without PVT, respectively. RESULTS Levels of the FVIIa-AT complex were significantly higher in noncirrhotic PVT subjects (132 ± 32 pM) than in healthy volunteers (108 ± 18 pM, P = 0.04). No significant difference in FVIIa-AT complexes was seen between cirrhotic patients with (64 ± 20 pM) or without (61 ± 24 pM) PVT. A linear correlation was seen between FVIIa-AT and FVIIa in noncirrhotic PVT subjects. In cirrhotic patients, FVIIa-AT complexes depended on both FVIIa and AT. CONCLUSION These results confirm the utility of the FVIIa-AT assay in identifying the hypercoagulable state of noncirrhotic patients because of a previous thrombotic event.
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Affiliation(s)
- V Rossetto
- Department of Cardiologic, Thoracic, and Vascular Sciences, 2nd Chair of Internal Medicine, University of Padua Medical School, Padua, Italy
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5
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Senzolo M, Rodriguez-Castro KI, Rossetto V, Radu C, Gavasso S, Carraro P, Zerbinati P, Sartori MT, Simioni P. Increased anticoagulant response to low-molecular-weight heparin in plasma from patients with advanced cirrhosis. J Thromb Haemost 2012; 10:1823-9. [PMID: 22712870 DOI: 10.1111/j.1538-7836.2012.04824.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Cirrhotic patients may present thrombotic complications that warrant anticoagulant therapy. However, the efficacy of low-molecular-weight heparin (LMWH) in this clinical setting is still unclear. AIMS/METHODS To evaluate the in vitro effect of LMWH on thrombin generation (TG) in cirrhotic patients at different stages of liver disease. Thirty cirrhotics (10 Child Pugh A, 10 Child Pugh B and 10 Child Pugh C), 10 subjects with inherited type 1 antithrombin (AT) defect and 10 healthy controls were studied. TG was determined at baseline and with anti-Xa levels after the addition of enoxaparin at 0.35 and 0.7 U anti-Xa mL. The endogenous thrombin potential (ETP) ratio at 0.35 and 0.7 U anti-Xa mL was obtained by dividing ETP with LMWH by ETP at baseline. RESULTS Mean AT levels in all cirrhotic subgroups and in patients with AT deficiency were significantly lower than in controls. The 0.35 ETP ratio was significantly lower in cirrhotic patients than in controls (0.26 ± 0.1 vs. 0.48 ± 0.1, P < 0.001) and the reduction paralleled the severity of liver disease, in spite of the concomitant decrease in AT and anti-Xa activity. AT-deficient subjects showed a significantly increased 0.35 ETP ratio compared with both cirrhotic patients and controls (0.69 ± 1 vs. 0.26 ± 0.1, P < 0.001, and vs. 0.48 ± 0.1, P = 0.04 respectively). LMWH at 0.7 U anti-Xa mL completely inhibited TG in 9/30 cirrhosis patients with more advanced liver disease (Child Pugh B and C), whereas complete TG abolition was seen in only 1/10 controls. CONCLUSIONS Cirrhotic patients show an increased response to LMWH, which correlates with the severity of liver disease, in spite of reduced AT and anti-Xa activity levels. Thrombin generation may be a useful tool to monitor the response to LMWH in cirrhotic patients.
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Affiliation(s)
- M Senzolo
- Multivisceral Transplant Unit, Department of Surgical and Gastroenterological Sciences. Padua University Hospital, Padua, Italy.
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Castoldi E, Duckers C, Radu C, Spiezia L, Rossetto V, Tagariello G, Rosing J, Simioni P. Homozygous F5 deep-intronic splicing mutation resulting in severe factor V deficiency and undetectable thrombin generation in platelet-rich plasma. J Thromb Haemost 2011; 9:959-68. [PMID: 21320286 DOI: 10.1111/j.1538-7836.2011.04237.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Coagulation factor (F) V deficiency is associated with a bleeding tendency of variable severity, but phenotype determinants are largely unknown. Recently, we have shown that three patients with undetectable plasma FV and mild bleeding symptoms had sufficient residual platelet FV to support thrombin generation in platelet-rich plasma (PRP). Therefore, we hypothesized that FV-deficient patients with severe bleeding manifestations may lack platelet FV. OBJECTIVES To characterize a FV-deficient patient with a severe bleeding diathesis. PATIENTS/METHODS We performed FV mutation screening and functional studies in a 31-year-old male (FV:C < 1%) with umbilical bleeding at birth, recurrent hemarthrosis and muscle hematomas, and a recent intracranial hemorrhage. RESULTS The proband was homozygous for a deep-intronic mutation (F5 IVS8 +268A→G) causing the inclusion of a pseudo-exon with an in-frame stop codon in the mature F5 mRNA. Although platelet FV antigen was detectable by immunoprecipitation followed by Western blotting, no FV activity could be demonstrated in the proband's plasma or platelets with a prothrombinase-based assay. Moreover, no thrombin generation was observed in PRP triggered with 1-50 pm tissue factor (even in the presence of platelet agonists), whereas an acquired FV inhibitor was excluded. Clot formation in the proband's whole blood, as assessed by thromboelastometry, was markedly delayed but not abolished. CONCLUSIONS This is the first report of a pathogenic deep-intronic mutation in the F5 gene. Our findings indicate that the minimal FV requirement for viability is extremely low and suggest that thrombin generation in PRP may predict bleeding tendency in patients with undetectable plasma FV.
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Affiliation(s)
- E Castoldi
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.
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7
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Rossetto V, Spiezia L, Dabrilli P, Radu C, Gavasso S, Simioni P. P.50 Effect of low dose LMWH “in vitro” addition on thrombin generation potential in healthy pregnant and non pregnant women. Thromb Res 2011. [DOI: 10.1016/s0049-3848(11)70105-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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Barbar S, Noventa F, Rossetto V, Ferrari A, Brandolin B, Perlati M, De Bon E, Tormene D, Pagnan A, Prandoni P. A risk assessment model for the identification of hospitalized medical patients at risk for venous thromboembolism: the Padua Prediction Score. J Thromb Haemost 2010; 8:2450-7. [PMID: 20738765 DOI: 10.1111/j.1538-7836.2010.04044.x] [Citation(s) in RCA: 709] [Impact Index Per Article: 50.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Prophylaxis of venous thromboembolism (VTE) in hospitalized medical patients is largely underused. We sought to assess the value of a simple risk assessment model (RAM) for the identification of patients at risk of VTE. METHODS In a prospective cohort study, 1180 consecutive patients admitted to a department of internal medicine in a 2-year period were classified as having a high or low risk of VTE according to a predefined RAM. They were followed-up for up to 90 days to assess the occurrence of symptomatic VTE complications. The primary study outcome was to assess the adjusted hazard ratio (HR) of VTE in high-risk patients who had adequate in-hospital thromboprophylaxis in comparison with those who did not, and that of VTE in the latter group in comparison with low-risk patients. RESULTS Four hundred and sixty-nine patients (39.7%) were labelled as having a high risk of thrombosis. VTE developed in four of the 186 (2.2%) who received thromboprophylaxis, and in 31 of the 283 (11.0%) who did not (HR of VTE, 0.13; 95% CI, 0.04-0.40). VTE developed also in two of the 711 (0.3%) low-risk patients (HR of VTE in high-risk patients without prophylaxis as compared with low-risk patients, 32.0; 95% CI, 4.1-251.0). Bleeding occurred in three of the 186 (1.6%) high-risk patients who had thromboprophylaxis. CONCLUSIONS Our RAM can help discriminate between medical patients at high and low risk of VTE. The adoption of adequate thromboprophylaxis in high-risk patients during hospitalization leads to longstanding protection against thromboembolic events with a low risk of bleeding.
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Affiliation(s)
- S Barbar
- Department of Cardiothoracic and Vascular Sciences, Second Division of Internal Medicine, University of Padua, Padova, Italy
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Spiezia L, Radu C, Gavasso S, Rossetto V, Abalotti C, Fadin M, Dabrilli P, Woodhams B, Simioni P. PO-30 Procoagulant phospholipids in patients with venous thromboembolism and cancer. Thromb Res 2010. [DOI: 10.1016/s0049-3848(10)70080-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Spiezia L, Campello E, Rossetto V, Gavasso S, Dalla Valle F, Zerbinati P, Woodhams B, Simioni P. PO-43 Hypofibrinolysis in patients with venous thromboembolism and cancer. Thromb Res 2010. [DOI: 10.1016/s0049-3848(10)70093-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Rossetto V. General framework for multiple scattering of polarized waves including anisotropies and Berry phase. Phys Rev E Stat Nonlin Soft Matter Phys 2009; 80:056605. [PMID: 20365089 DOI: 10.1103/physreve.80.056605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 08/10/2009] [Indexed: 05/29/2023]
Abstract
We develop a framework for the multiple scattering of a polarized wave. We consider particles with spin propagating in a medium filled with scatterers. We write the amplitudes of each spin eigenstate in a local mobile frame. One of the axes is in the direction of propagation of the particle. We use this representation to define a directional Green's operator of the homogeneous medium and also to write the spin-dependent scattering amplitudes. We show that this representation reveals a Berry phase. We establish a generalized Green-Dyson equation for the multiple-scattering problem in this framework. We show that the generalized Green-Dyson equation can be solved by linear algebra if one uses a representation of the rotations based on Wigner D matrices. The properties of light scattering are retrieved if we use spin 1 particles. Our theory allows to take into account several kinds of anisotropies such as circular or linear dichroism and birefringence, Faraday effects, and Mie scattering within the same formalism. Several anisotropies can be present at the same time.
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Affiliation(s)
- V Rossetto
- Université Joseph Fourier, Grenoble, France.
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Campello E, Spiezia L, Castelli M, Rossetto V, Radu C, Tormene D, Simioni P. O5 Microparticles plasma levels in women with venous thromboembolism and cancer. Thromb Res 2009. [DOI: 10.1016/s0049-3848(09)70030-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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13
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Rossetto V, Dabrilli P, Spiezia L, Campello E, Gavasso S, Facchin M, Simioni P. P32 Endogenous thrombin potential (ETP) in 22 pregnant women. Thromb Res 2009. [DOI: 10.1016/s0049-3848(09)70077-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Spiezia L, Stocco E, Campello E, Rossetto V, Bertini D, Castelli M, Ferri V, Ambrosini A, Simioni P. P33 Whole blood coagulation thrombelastometry (ROTEM®) profile in 19 pregnant women. Thromb Res 2009. [DOI: 10.1016/s0049-3848(09)70078-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Spiezia L, Rossetto V, Zuin A, Pagnan A, Simioni P. Acute oppressive chest pain in a 66-year-old woman with a recent Amplatzer device closure of patent foramen ovale. Intern Emerg Med 2007; 2:229-30. [PMID: 17912492 DOI: 10.1007/s11739-007-0064-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2006] [Accepted: 10/27/2006] [Indexed: 11/30/2022]
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Abstract
Long ranged electrostatic interactions are time consuming to calculate in molecular dynamics and Monte Carlo simulations. We introduce an algorithmic framework for simulating charged particles which modifies the dynamics so as to allow equilibration using a local Hamiltonian. The method introduces an auxiliary field with constrained dynamics so that the equilibrium distribution is determined by the Coulomb interaction. We demonstrate the efficiency of the method by simulating a simple, charged lattice gas.
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Affiliation(s)
- A C Maggs
- Laboratoire de Physico-Chime Théorique, ESPCI-CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France
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Abstract
We study theoretically the polarization state of light in multiple scattering media in the limit of low contrast in the refractive index. Linearly polarized photons are randomly rotated due to the Berry phase associated with the scattering path. For circularly polarized light independent speckle patterns are found for the two helical states. The statistics of the geometric phase is related to the writhe distribution of semiflexible polymers such as DNA.
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Affiliation(s)
- A C Maggs
- ESPCI-CNRS, 10 Rue Vauquelin, Paris 75005, France
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