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1.
Phys Rev Lett ; 126(8): 083603, 2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33709745

RESUMEN

We demonstrate a source for correlated pairs of atoms characterized by two opposite momenta and two spatial modes forming a Bell state only involving external degrees of freedom. We characterize the state of the emitted atom beams by observing strong number squeezing up to -10 dB in the correlated two-particle modes of emission. We furthermore demonstrate genuine two-particle interference in the normalized second-order correlation function g^{(2)} relative to the emitted atoms.

2.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38065135

RESUMEN

The Streaked Optical Pyrometer (SOP) is a visible diagnostic widely used to study the warm dense matter regime at high energy laser facilities, gas guns, or ion accelerators. It is usually coupled with a Velocity Interferometer System for Any Reflector (VISAR) diagnostic for simultaneous shock wave velocity, reflectivity, and temperature measurements to study the Equation of State (EOS) of materials. While VISAR is a well-mastered technology that provides velocity measurements with low relative uncertainties (close to percent), SOP diagnostics still suffer from high imprecision. In this article, we present a new calibration method in order to obtain absolute temperature measurements with reduced uncertainties. This approach is based on a novel light source: a Ce:YAG luminescent concentrator pumped by LEDs. This device produces enough optical power for calibration at the nanosecond sweep duration of the streak camera. As a demonstration, it has first been installed at the LULI facility and tested on quartz samples shocked at temperatures above 4000 K.

3.
Phys Rev Lett ; 109(22): 220401, 2012 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-23368107

RESUMEN

We have modulated the density of a trapped Bose-Einstein condensate by changing the trap stiffness, thereby modulating the speed of sound. We observe the creation of correlated excitations with equal and opposite momenta, and show that for a well-defined modulation frequency, the frequency of the excitations is half that of the trap modulation frequency.

4.
Phys Rev Lett ; 108(26): 260401, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-23004939

RESUMEN

The Cauchy-Schwarz (CS) inequality-one of the most widely used and important inequalities in mathematics-can be formulated as an upper bound to the strength of correlations between classically fluctuating quantities. Quantum-mechanical correlations can, however, exceed classical bounds. Here we realize four-wave mixing of atomic matter waves using colliding Bose-Einstein condensates, and demonstrate the violation of a multimode CS inequality for atom number correlations in opposite zones of the collision halo. The correlated atoms have large spatial separations and therefore open new opportunities for extending fundamental quantum-nonlocality tests to ensembles of massive particles.

5.
Phys Rev Lett ; 105(19): 190402, 2010 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-21231151

RESUMEN

We demonstrate sub-Poissonian number differences in four-wave mixing of Bose-Einstein condensates of metastable helium. The collision between two Bose-Einstein condensates produces a scattering halo populated by pairs of atoms of opposing velocities, which we divide into several symmetric zones. We show that the atom number difference for opposing zones has sub-Poissonian noise fluctuations, whereas that of nonopposing zones is well described by shot noise. The atom pairs produced in a dual number state are well adapted to sub-shot-noise interferometry and studies of Einstein-Podolsky-Rosen-type nonlocality tests.

6.
Phys Rev Lett ; 104(15): 150402, 2010 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-20481974

RESUMEN

We investigate the atom-optical analog of degenerate four-wave mixing by colliding two Bose-Einstein condensates of metastable helium. The momentum distribution of the scattered atoms is measured in three dimensions. A simple analogy with photon phase matching conditions suggests a spherical final distribution. We find, however, that it is an ellipsoid with radii smaller than the initial collision momenta. Numerical and analytical calculations agree with this and reveal the interplay between many-body effects, mean-field interaction, and the anisotropy of the source condensate.

7.
Ultrasound Obstet Gynecol ; 36(5): 635-40, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20617508

RESUMEN

OBJECTIVES: Three-dimensional (3D) Doppler quantification within the uteroplacental unit could be of great help in understanding and screening for pre-eclampsia and intrauterine growth restriction. Yet the correlation between 3D Doppler indices and true blood flow has not been confirmed in vivo. The aim of this study was to evaluate this correlation in a pregnant sheep model. METHODS: A blood flow quantitative sensor and a controllable vascular occlusion system were placed around the common uterine artery in seven sheep in late pregnancy, while all the other arterial supplies were ligated. Several occlusion levels were applied, from 0 to 100%, simultaneously with 3D Doppler acquisitions of several placentomes, using standardized settings. Each placentome was analyzed using VOCAL™ (Virtual Organ Computer-aided AnaLysis) software. The correlation between true blood flow and Doppler indices (vascularization index (VI), flow index (FI) and vascularization flow index (VFI)) was evaluated, together with measurement reproducibility. RESULTS: Forty-eight acquisitions were analyzed. All 3D Doppler indices were significantly correlated with true blood flow. Higher correlations were observed for VI and VFI (r = 0.81 (0.74-0.87), P < 0.0001 and r = 0.75 (0.67-0.82), P < 0.0001) compared with FI (r = 0.53 (0.38-0.64) P < 0.0001). Both intra- and interobserver reproducibility were high, with intraclass correlation coefficients of at least 0.799. CONCLUSION: This is the first in-vivo experimental study confirming a significant correlation between true blood perfusion and quantitative 3D Doppler indices measured within the uteroplacental unit. These results confirm the potential usefulness of 3D Doppler ultrasound for the assessment of placental vascular insufficiency both in clinical cases and in a research setting.


Asunto(s)
Placenta/diagnóstico por imagen , Circulación Placentaria/fisiología , Arteria Uterina/diagnóstico por imagen , Animales , Femenino , Imagenología Tridimensional , Placenta/irrigación sanguínea , Embarazo , Flujo Sanguíneo Regional/fisiología , Oveja Doméstica , Ultrasonografía Doppler , Ultrasonografía Prenatal , Arteria Uterina/fisiopatología
8.
Meat Sci ; 81(1): 270-4, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22063994

RESUMEN

A total of twenty two Large White X Landrace castrated males were slaughtered at 30, 70, 110 or 140kg BW. Carcasses were weighed and cut into four primal cuts (belly, ham, loin, and shoulder). Each cut was weighed and dissected into bone, muscle, skin, and intermuscular and subcutaneous adipose tissues. Kidney fat was also taken and weighed. Kidney fat grew more rapidly than subcutaneous or intermuscular fat averaged over all four cuts. In the shoulder and loin, about one third of total adipose tissue was in the intermuscular fraction. In the belly, there was as much (in 30-110kg BW pigs) or more (in 140kg BW pigs) intermuscular than subcutaneous adipose tissue. In the ham, the intermuscular fraction of adipose tissue grew more slowly than the subcutaneous one, so that it represented less than one fourth of total ham adipose tissue in 140kg BW pigs. Intermuscular adipose tissue exhibited a lower lipid content than subcutaneous adipose tissue, whatever the body weight, but the differences in lipid content between the adipose tissues decreased with increasing weight. These results show that the relative development of intermuscular and subcutaneous adipose tissues differs according to anatomical location.

9.
Animal ; 12(6): 1287-1295, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29143706

RESUMEN

The perspective of a possible ban on surgical castration of male pigs in the EU is a real challenge for pork production systems aiming at (very) high-quality products. Information was collected from a total of 272 situations in 16 European countries, including 170 situations related to EU protected designations (Database of Origin & Registration (DOOR) database) and 102 other situations related to high-quality products or differentiated production systems, in order to evaluate their potential sensitivity to the use of entire male pigs along four dimensions: BT_Inc, likelihood of increased levels of boar taint compounds compared with conventional production of entire males; BT_Per, extent to which (some of) the associated pork product(s) are susceptible to perception of boar taint by consumers; FatQQ, likelihood that the quality of (some of) the related products is decreased due to the lower fat quantity and quality in entire males; Manag, increased likelihood of animal management and welfare problems compared with conventional production of entire males. Situations corresponding to EU protected designations (DOOR situations) were on average more sensitive to entire male production but 11% of the non-DOOR situations were highly potentially sensitive, whereas one-third of the DOOR situations had low potential sensitivity. In total, 37% of the situations where castration is not formally specified as mandatory exhibited high potential sensitivity to entire male production. Three main patterns of situations were identified via ascending hierarchical clustering. A first pattern including 31% of the DOOR situations and 74% of the other ones, had potentially no increased risk compared with conventional production of entire males. A second pattern including 28% of the DOOR situations and 16% of the other ones had a high, moderate and low potential sensitivity for FatQQ, BT_Inc and Manag, respectively. The third pattern including 41% of the DOOR situations and 11% of the other situations had high potential sensitivity for BT_Inc and FatQQ, associated with moderate to high sensitivity for Manag. The approach used to evaluate the sensitivity to entire male pig production from the limited information collected for this study has many limitations. More precise approaches using more specific information are needed to evaluate the actual sensitivity of individual situations to the use of entire male pigs. Still, the present study provides a first global insight on the capacity of European production systems aiming at high-quality products to use entire male pigs as an alternative to surgical castration.


Asunto(s)
Orquiectomía , Carne Roja , Porcinos , Animales , Europa (Continente) , Masculino , Control de Calidad
10.
Meat Sci ; 137: 235-243, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29223558

RESUMEN

A consumer study was performed in four EU countries to further clarify the acceptability of meat with boar taint. In Denmark, France, Italy and Poland, a total of 476 female consumers evaluated 8 meat patties from boars with varying levels of skatole (0.10-0.40µg/g fat tissue) and androstenone (0.47-2.00 µg/g fat tissue), in a pair-wise comparison with patties from castrates. Boar meat patties were always less preferred than the castrate meat patties, regardless of the level of androstenone and skatole. Acceptability of the boar meat patties decreased with increasing skatole level. In samples with low skatole levels, higher levels of androstenone also reduced acceptability among androstenone sensitive consumers. No clear threshold levels for androstenone and skatole could be identified. Maps presenting the reduction in preference due to increasing levels of skatole and androstenone, and corrected for the general acceptance of the meat product were developed, taking into account androstenone sensitivity. Further work is needed, covering the whole range of androstenone and skatole levels found in entire male pigs and for a wider set of meat products.


Asunto(s)
Comportamiento del Consumidor , Carne Roja/análisis , Adolescente , Adulto , Anciano , Androstenos/análisis , Animales , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Orquiectomía/veterinaria , Escatol/análisis , Olfato , Porcinos , Gusto
11.
Meat Sci ; 76(1): 54-60, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-22064191

RESUMEN

Lipid contents and compositions were measured in 35 pigs from seven genotype-sex groups with large variations in body composition. The animals were slaughtered at 115kg live weight, and the left side was separated into four primal cuts: belly, ham, loin, and shoulder. Samples of adipose tissues were taken from flare fat and from subcutaneous and intermuscular adipose tissues in each of the four cuts. In the loin, the outer and inner layers of subcutaneous adipose tissue were sampled separately. Total lipid content was lower in intermuscular than in subcutaneous adipose tissue. It was the highest in flare fat. There was a gradient of decreasing unsaturation from the outer layer of subcutaneous adipose tissue, to the inner layer, to intermuscular adipose tissue, to flare fat. The monounsaturated fatty acid concentrations followed the same pattern. There was a statistically positive correlation between the linoleic acid concentration of the different adipose tissues and the half carcass muscle content.

12.
J Dent Res ; 96(12): 1406-1413, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28796952

RESUMEN

Cell-based partial pulp regeneration is one of the promising approaches to obtain newly formed functional dentin-pulp complex. It relies on the preservation of the healthy tissue while regenerating the damaged pulp. The aim of this study was to investigate whether this regenerative process could be achieved by implanting porcine dental pulp cells (pDPCs) in pulp defects in the minipig. By split-mouth model, self-assembling injectable nanopeptide hydrogel, with and without pDPCs, was implanted after cameral pulpotomy in premolars and molars. At day 21 after surgery, 3-dimensional morphometric characterization, Masson's trichrome staining, and immunolabeling for DSP and BSP (dentin sialoprotein and bone sialoprotein) were performed on treated teeth. This study demonstrated no pulp regeneration but systematic reparative dentinogenesis. In fact, regardless of the presence of pDPCs in the scaffold, an osteodentin bridge-the microarchitecture of which significantly differed from the native dentin-was systematically obtained. Furthermore, the presence of pDPCs significantly affected the microstructure of the dentin bridges. In the radicular area of each treated tooth, hyperemia in the remaining pulp and external root resorptions were observed. Under the conditions tested in this work, pulp regeneration was not achieved, which highlights the need of further investigations to develop favorable regenerative microenvironment.


Asunto(s)
Pulpa Dental/citología , Pulpotomía , Regeneración , Ingeniería de Tejidos/métodos , Animales , Proliferación Celular , Dentina Secundaria/fisiología , Proteínas de la Matriz Extracelular/análisis , Hidrogeles , Sialoproteína de Unión a Integrina/análisis , Fosfoproteínas/análisis , Sialoglicoproteínas/análisis , Coloración y Etiquetado , Porcinos , Porcinos Enanos , Microtomografía por Rayos X
13.
Meat Sci ; 72(1): 146-54, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22061385

RESUMEN

The aim of this study was to determine the suitability of magnetic resonance imaging (MRI) to predict tissue composition of pig carcasses and cuts. Twenty-four pig carcasses were cut into the four primary cuts that were analyzed with a low field MRI imager before a total dissection. Images were then processed to identify and quantify pixels representing muscle, subcutaneous fat and intermuscular fat fractions. MRI provided a good prediction of muscle content in cuts and carcasses, with R(2) ranging from 0.970 to 0.997. The prediction was slightly less accurate for total fat (0.951⩽R(2)⩽0.986) or subcutaneous fat (0.918⩽R(2)⩽0.994). Finally, the prediction of intermuscular fat content in considering intermuscular fat classified pixels was acceptable only for the belly (R(2)=0.837).

14.
Sci Rep ; 6: 34187, 2016 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-27725688

RESUMEN

Quantum technologies will ultimately require manipulating many-body quantum systems with high precision. Cold atom experiments represent a stepping stone in that direction: a high degree of control has been achieved on systems of increasing complexity. However, this control is still sub-optimal. In many scenarios, achieving a fast transformation is crucial to fight against decoherence and imperfection effects. Optimal control theory is believed to be the ideal candidate to bridge the gap between early stage proof-of-principle demonstrations and experimental protocols suitable for practical applications. Indeed, it can engineer protocols at the quantum speed limit - the fastest achievable timescale of the transformation. Here, we demonstrate such potential by computing theoretically and verifying experimentally the optimal transformations in two very different interacting systems: the coherent manipulation of motional states of an atomic Bose-Einstein condensate and the crossing of a quantum phase transition in small systems of cold atoms in optical lattices. We also show that such processes are robust with respect to perturbations, including temperature and atom number fluctuations.

15.
Biochim Biophys Acta ; 1263(3): 261-5, 1995 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-7548216

RESUMEN

The aim of this paper is to gather and complete data about four members of a new gene family. Mutation in SUR4 gene was originally selected as a suppressor of defects caused by mutations in RVS161 or RVS167 genes. Cloning and sequencing of the SUR4 gene were performed. The deduced protein contains six putative transmembrane domains. Sequence comparison revealed that two yeast genes, FEN1 and JO343, shared significant similarities with SUR4. Mutants for SUR4 and FEN1 have the same pleiotropic phenotype, including bud localization defects, resistance to an immunosuppressor and resistance to ergosterol biosynthesis inhibitors. The double inactivation of SUR4 and FEN1 genes is lethal. These data and other aspects implicating SUR4 in glucose metabolism, suggest an involvement of these genes in the dynamics of cortical actin cytoskeleton in response to nutrient availability. Moreover, the existence of a fourth homologous gene in C. elegans extends the family to pluricellular organisms.


Asunto(s)
Proteínas del Citoesqueleto , Genes Fúngicos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Secuencia de Bases , Proteínas Fúngicas/genética , Proteínas de Microfilamentos , Datos de Secuencia Molecular , Mutación , Fenotipo , Alineación de Secuencia
16.
J Cardiovasc Surg (Torino) ; 46(5): 485-9, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16278639

RESUMEN

AIM: Current treatment of thoraco-abdominal aortic aneurysms is surgical. Despite significant advances in surgical technique and anesthetic management, significant morbidity and mortality remain associated with their repair. In compliance with principles of reducing postoperative morbidity, we developed a thoraco-abdominal endovascular graft in experimental models of type III and type IV thoraco-abdominal aortic aneurysm. This device had to preserve the vascularization of the visceral arteries while ensuring full aneurysmal exclusion. METHODS: Six implantations of the endovascular graft were performed. This graft was a modular system, made of: 1) a custom made main body containing 4 prosthetic visceral branches, 2) 4 self-expandable stent-grafts connecting prosthetic visceral branches with visceral arteries, 3) a custom made tubular endovascular graft connecting the main body with one of the iliac arteries. RESULTS: On angiographic controls, full aneurysmal exclusion was achieved while maintaining visceral artery perfusion. At the end of each procedure, the experimental model was opened. Macroscopic examination showed harmonious thoraco-abdominal endovascular graft deployments, without abnormal component constraint or kinking. There was no discordance between macroscopic and angiographic CONCLUSIONS: Our experimental work led to the development of a thoraco-abdominal endovascular graft, demonstrating feasibility of thoraco-abdominal aneurysm endoluminal treatment on an in vitro model close to the anatomical conditions observed in human pathology.


Asunto(s)
Angioplastia , Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular , Prótesis Vascular , Humanos , Modelos Cardiovasculares , Diseño de Prótesis
17.
Exp Hematol ; 6(8): 679-87, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-361428

RESUMEN

The etiology of aplastic anemia is unknown. A stem cell lesion caused by a toxin, virus or microenvironment defect is the main hypothesis. An autoimmune origin has been recently suspected. In an attempt to demonstrate the autoimmune origin of the disease, 17 patients with severe aplastic anemia were treated with antilymphocyte globulin (ALG). Nine patients showed no improvement, developed infectious or hemorrhagic complications and died within 1 to 7 months. In contrast, eight patients had a prompt rise of granulocyte and reticulocyte counts. Although the hematological reconstitution is not complete, these eight patients are still alive between 11 months and 24 months after treatment. This study shows that ALG may have a beneficial effect in the treatment of patients with severe aplastic anemia.


Asunto(s)
Andrógenos/uso terapéutico , Anemia Aplásica/terapia , Suero Antilinfocítico/uso terapéutico , Adolescente , Adulto , Anemia Aplásica/sangre , Anemia Aplásica/tratamiento farmacológico , Anemia Aplásica/mortalidad , Células de la Médula Ósea , Niño , Preescolar , Ensayos Clínicos como Asunto , Ensayo de Unidades Formadoras de Colonias , Evaluación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Exp Hematol ; 26(7): 620-6, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9657137

RESUMEN

To evaluate the relative role of plasma and platelet von Willebrand factor (vWF) pools in hemostasis and arterial thrombogenesis, pigs with vW disease (vWD) were injected with vWF concentrate and/or grafted with bone marrow from a normal pig. Hemostasis was assessed by measurement of ear immersion bleeding time, factor VIII (FVIII) activity, and plasma and platelet vWF antigen levels. The thrombotic process was explored at 650 s(-1) and 1600 s(-1) in an ex vivo cylindrical perfusion chamber. Pigs with vWD exhibited a prolonged bleeding time (>30 minutes) compared with normal pigs (<5 minutes); in addition, they showed normal platelet adhesion and thrombus formation at 650 s(-1) but profoundly reduced platelet adhesion and thrombus formation at 1600 s(-1). Each experiment was performed before and 3 and 24 hours after injection of vWF concentrate. In our bleeding time study, only plasma vWF restoration induced a partial but delayed correction (24 hours postinjection), which was correlated with the highest measured level of FVIII activity. In the perfusion chamber model, restoration of plasma or platelet vWF pools resulted in similar partial correction of platelet adhesion and average thrombus size. In the perfused pigs, the maximum correction occurred 3 hours postinjection. Platelet deposition reached normal values after vWF concentrate was injected into a grafted pig. The present results suggest that when both plasma and platelet vWF levels are restored in vWD pigs, bleeding time and the thrombotic process are normalized according to different kinetics and with differing degrees of effectiveness.


Asunto(s)
Plaquetas/fisiología , Hemostasis/fisiología , Trombosis/fisiopatología , Factor de von Willebrand/fisiología , Animales , Tiempo de Sangría , Susceptibilidad a Enfermedades , Perfusión , Adhesividad Plaquetaria/fisiología , Estrés Mecánico , Porcinos
19.
Exp Hematol ; 24(5): 585-91, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8605962

RESUMEN

To assess the relative in vivo roles of von Willebrand factor (vWF) of different origins, we performed crossed bone marrow transplantations (BMTs) among normal pigs and pigs with the von Willebrand disease(vWF). The two groups were fully compatible immunologically according to typing by swine leukocyte antigen (SLA). After total-body irradiation (8-10 Gy), all pigs received 0.5X10(9) to 10(10)/kg mononuclear bone marrow cells without any immunosuppression. The nadir of aplasia occurred between days 5 and 7 after irradiation (white blood cell [WBC] count 0.6X10(9)/L, platelet [Plt] count 76X10(9)/L. Three weeks after the graft, WBC and Plt counts had returned to normal levels. Animals were followed for at lease 50 days, during which no bone marrow rejection occurred; no evidence of graft-vs-host disease (GVHD) was observed. Each BMT was confirmed by karyotype analysis. In the six homozygous pigs with vWD grafted with normal marrow, platelet vWF antigen (vWFAg) and platelet vWF activity rose from <3 to 450 U/dl with a normal multimeric pattern; plasma vF increases slightly. No correction of bleeding time was observed. In the five normal pigs grafted with bone marrow form pigs with vWD, platelet vWFAg and platelet vWF activity decreased from >100 U/dl to undetectable levels; bleeding time and plasma vWFAg remained unchanged. A derivative of normal porcine plasma, a concentrate containing factor VIII and vWF, was infused into a homozygous vWD pig before and after BMT from a normal pig. Co correction of bleeding time was obtained, even though plasma nd platelet vWFAg levels were normal. W concluded that crossed BMT among SLA-identical pigs is a feasible model of studying the synthesis and the roles of vWF in hemostasis and thrombosis.


Asunto(s)
Factor de von Willebrand/fisiología , Animales , Coagulación Sanguínea , Trasplante de Médula Ósea , Quimera , Factor VIII/metabolismo , Hemostasis , Antígenos de Histocompatibilidad/inmunología , Antígenos de Histocompatibilidad Clase II , Modelos Biológicos , Porcinos , Factor de von Willebrand/química , Factor de von Willebrand/genética
20.
J Thromb Haemost ; 2(6): 925-30, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15140128

RESUMEN

The activity of SanOrg123781A, a new synthetic antithrombotic drug inhibiting both factor Xa and thrombin through antithrombin (AT), was compared to that of unfractionated heparin (UFH) and of the synthetic pentasaccharide (fondaparinux, SP) in an ex vivo arterial thrombosis model in the pig. Six groups of four pigs were administered intravenously with SanOrg123781A (1, 3, 10 and 30 nmol kg(-1)), UFH (30 nmol kg(-1)) or SP (30 nmol kg(-1)). In this arterial model in which platelet thrombus was formed on a thrombogenic surface under a constant high shear rate, UFH and SP had moderate antithrombotic effects while SanOrg123781A exhibited a strong, dose-dependent inhibitory activity on platelet adhesion and platelet thrombus formation. In contrast to UFH, SanOrg123781A did not modify the activated partial thromboplastin time (aPTT) even at 30 nmol kg(-1), but strongly inhibited thrombin generation. At the same dose, despite a lower antithrombotic activity than SanOrg123781A, UFH significantly affected all the coagulation parameters. Taken together, these results show that SanOrg123781A, due to its potent and selective antifactor Xa and antifactor IIa activities is a promising new antithrombotic agent even in arterial setting.


Asunto(s)
Polisacáridos/farmacocinética , Trombosis/tratamiento farmacológico , Animales , Plaquetas/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Inhibidores del Factor Xa , Fondaparinux , Heparina/administración & dosificación , Heparina/farmacocinética , Heparina/farmacología , Tiempo de Tromboplastina Parcial , Polisacáridos/administración & dosificación , Polisacáridos/farmacología , Protrombina/antagonistas & inhibidores , Porcinos , Trombosis/prevención & control
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