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International audience; The understanding of plasma–liquid interactions is of major importance, not only in physical chemistry, chemical engineering and polymer science, but in biomedicine as well as to better control the biological processes induced on/in biological samples by Cold Atmospheric Plasmas (CAPs). Moreover, plasma–air interactions have to be particularly considered since these CAPs propagate in the ambient air. Herein, we developed a helium-based CAP setup equipped with a shielding-gas device, which allows the control of plasma–air interactions. Thanks to this device, we obtained specific diffuse CAPs, with the ability to propagate along several centimetres in the ambient air at atmospheric pressure. Optical Emission Spectroscopy (OES) measurements were performed on these CAPs during their interaction with a liquid medium (phosphate-buffered saline PBS 10 mM, pH 7.4) giving valuable information about the induced chemistry as a function of the shielding gas composition (variable O2/(O2 + N2) ratio). Several excited species were detected including N2+(First Negative System, FNS), N2(Second Positive System, SPS) and HO˙ radical. The ratios between nitrogen/oxygen excited species strongly depend on the O2/(O2 + N2) ratio. The liquid chemistry developed after CAP treatment was investigated by combining electrochemical and UV-visible absorption spectroscopy methods. We detected and quantified stable oxygen and nitrogen species (H2O2, NO2−, NO3−) along with Reactive Nitrogen Species (RNS) such as the peroxynitrite anion ONOO−. It appears that the RNS/ROS (Reactive Oxygen Species) ratio in the treated liquid depends also on the shielding gas composition. Eventually, the composition of the surrounding environment of CAPs seems to be crucial for the induced plasma chemistry and consequently, for the liquid chemistry. All these results demonstrate clearly that for physical, chemical and biomedical applications, which are usually achieved in ambient air environments, it is necessary to realize an effective control of plasma–air interactions.

We report the pharmacodynamic properties of tinzaparin (175 U/kg antifactor Xa) given as a single daily administration for 5 consecutive days to 14 healthy volunteers as a known safe, effective treatment of deep vein thrombosis and pulmonary embolism. The Cmax for antifactor Xa (0.87 +/- 0.15 U/ml) was associated with a 2.4 +/- 0.5-fold prolongation of the activated partial thromboplastin time (APTT) and a high antithrombin activity (0.38 +/- 0.1 U/ml). The Cmax value of antifactor Xa was 1.5- and twofold lower than those generated by similar doses of nadroparin and enoxaparin respectively. The clearance of antifactor Xa activity (1.29 +/- 0.2 l/h) was 1.5- and twofold greater than those reported for nadroparin and enoxaparin respectively. These results indicated that the antithrombotic and prohaemorrhagic effects of a low molecular weight heparin were independent from the absolute levels of antifactor Xa activities and from the prolongation of the APTT.

Active site-inhibited factor VIIa (FFR-rFVIIa) competes with factor VIIa (FVIIa) for binding to tissue factor (TF) and exerts an anti-thrombotic effect. We report an evaluation of the anti-thrombotic properties of FFR-rFVIIa in a model of thrombosis involving two thrombogenic surfaces. Uncoated glass capillaries or glass capillaries coated with TF were incorporated into an arterioarterial shunt in the rat and the occlusion time (OT) of the shunt was determined. An anti-thrombotic activity of FFR-rFVIIa was shown only on the TF-coated surface: the OT of the shunt was significantly prolonged, from 167 ± 34 s in control animals to 312 ± 42 s after i.v. bolus administration of 4 mg/kg FFR-rFVIIa. This OT was similar to those observed with the uncoated shunts in untreated animals (353 ± 84 s). In vitro preincubation of the TF-coated shunt with FFR-rFVIIa significantly prolonged the OT to 245 ± 45 s in the absence of detectable amounts of FFR-rFVIIa in the plasma. rFFR-rFVIIa weakly prolonged the tail template bleeding time by a factor of 1·5. This effect was more pronounced in animals pretreated with heparin. The anti-thrombotic and prohaemorrhagic effects of FFR-rFVIIa were totally reversed by administration of an equidose of rFVIIa. These results provide new information on the pharmacological properties of FFR-rFVIIa that will be useful for its clinical development.

In this paper, the word symbiosis (from the Greek Sumbiōsis) is used in its original sense and refers to all organisms which interact with each other, whether this association is beneficial, neutral or harmful to the host (mutualism, commensalism and parasitism). Symbiosis is found in every aspect of the living world. It is seen between infectious agents, in tropical disease vectors, in the human body and in illnesses. Immune-dependent symbiosis between infectious agents and the host is an opposite and complementary mechanism to defense and rejection immunity. This duality is found in many biological functions. Our comprehensive, compelling theory provides an overview of the different sites and mechanisms where symbiosis may occur. These symbioses are ongoing, four-dimensional evolutionary processes. They are gradually shifting away from phenotypic symbioses, including exosymbioses (metazoans, protozoa, yeasts, bacteria, viruses), tissular endosymbioses (metazoans, yeast), toward cytoplasmic and nuclear endosymbioses (protozoa, yeasts, bacteria, RNA viruses), before finally arriving at genomic endosymbioses (mitochondrial DNA, DNA viruses, retroviruses, transposable elements), which is the ultimate goal of symbiotic evolution, giving rise to new human genes. The phenotype/genotype boundary is thus traversable. A immunological process that initially takes an immunopathologic inflammatory form, but develops into a non-inflammatory immuno-physiological state. A process that leads from parasitism to mutualism and commensalism, and ultimately to the emergence of new species. This article hinges on the primary author’s extensive experience in tropical medicine allied with meticulous bibliographic research. Our intention is to offer a fresh perspective on the different forms of physiological and pathological symbioses in humans and illustrate them with examples. The general control mechanisms of symbiosis are discussed including immune tolerance and rejection. Innate immunity requires an assumption about the evolutionary mechanisms involved in recognition of immune innate material. In adaptive immunity we develop the hypothetical role of antibody dependent cell tolerance (ADCT) in which cytophilic antibodies support immune-dependent symbiosis. This includes then the crucial role of growth and differentiation factors in symbiotic mechanisms. We will list ten areas of research and application in fundamental science (self-genomics, immune innate material), epidemiology, prevention (nuclear endomembrane, symbiogenic vaccination) and treatment (including differentiation therapy), which bring together internists, infectious disease specialists, oncologists, biologists, immunologists, geneticists, epidemiologists, nutritionists, botanists and evolutionary scientists.; Notre article apporte une nouveau regard sur la symbiose et l'immunologie chez l'homme.Pour les auteurs le mot symbiose, du grec sumbiōsis retrouve son sens originel et regroupe toutes les formes du « vivre ensemble » qu’elles soient bénéfiques, neutres ou néfastes pour l’hôte (mutualisme, commensalisme, parasitisme). La symbiose est omniprésente dans le monde vivant. Elle est observée entre les agents infectieux, chez les vecteurs des maladies tropicales, chez l’homme dans notre physiologie et nos pathologies. La symbiose immunodépendante des agents infectieux et de l’hôte est le versant contraire et complémentaire de l’immunité de défense et de rejet. Cette dualité est commune dans les fonctions biologiques.Notre théorie globale,cohérente et fertile apporte une vue d’ensemble des différentes localisations et des mécanismes de la symbiose impliquant les agents infectieux et l’hôte humain. Elle s’inscrit dans un continuum évolutionniste à quatre dimensions complémentaires. Un mouvement déterministe qui conduit progressivement de la symbiose phénotypique comprenant l’exosymbiose (métazoaires, protozoaires, levures, bactéries, virus) suivie de l’endosymbiose tissulaire (métazoaires, levures), cytoplasmique et nucléaire (protozoaires, levures, bactéries, virus à ARN), à l’endosymbiose génomique (ADN mitochondrial, virus à ADN, rétrovirus, éléments transposables) qui est le but final de l’évolution symbiotique, conduisant aux gènes humains. En conséquence la barriere entre phenotype et génotype serait perméable. Un processus immunologique qui va de l’immunopathologie inflammatoire à l’état immunophysiologique non inflammatoire. Un processus qui conduit du parasitisme initial au commensalisme et mutualisme jusqu’a l’apparition de nouvelles espèces.Etayé par l’expérience et les observations du premier auteur en médecine tropicale associée à une recherche bibliographique poussée, sont définies chez l’homme avec un nouveau regard et de nombreux exemples, les différentes formes de symbioses physiologiques et pathologiques. Les mécanismes généraux de contrôle de la symbiose sont étudiés. Ils comprennent l’immunologie de rejet et de tolérance. L’immunité innée comporte une hypothèse concernant les mécanismes évolutionnistes de reconnaissance du «matériel inné » et l’immunité adaptative de tolérance une hypothèse sur le rôle de l’antibody dependent cell tolerance (ADCT) faisant intervenir les anticorps facilitants cytophiles dans le processus de la symbiose immunodépendante. Ils comprennent ensuite l’action primordiale des facteurs de croissance et de différenciation dans les mécanismes de symbiose. Dans ce contexte , nous énumérons dix voies de recherches et d’applications en science fondamentale (« soi génomique », « matériel inné »), en épidémiologie, en prévention (endomembrane nucléaire, vaccination symbiogène) et en thérapeutique (dont les thérapies par différenciation) sous l’angle de notre théorie, pouvant mobiliser les internistes, infectiologues, oncologistes, biologistes, immunologistes, généticiens, epidémiologistes, nutritionnistes, botanistes, évolutionnistes.

To determine the effect of patient characteristics and of specific guidelines that were developed for managing warfarin therapy in older adults and included in an in-house computer program on anticoagulation quality.Thirteen-month observational study.Acute care, extended care, and rehabilitation geriatric wards of a teaching hospital in Paris, France.Hospitalized patients (N=307, mean age 86.1 +/- 6.1) treated with warfarin with a therapeutic international normalized ratio range of 2.0 to 3.0.Patients were assigned according to care unit to the computer-generated dosing group (CGD) or the standard management group (SM; usual physician-based care).Relationships between anticoagulation quality criteria and covariates (age, sex, warfarin indication, treatment phase, follow-up duration, model of care).According to multivariate analysis, only model of care and follow-up duration independently influenced anticoagulation control; the proportion of time within therapeutic INR range 2.0 to 3.0 was significantly greater in the CGD group than in the SM group (59% vs 48%, P=.004). When a wider INR range was analyzed (1.8-3.2), the proportion of time within range was 73% versus 64% (P=.006). Use of the computer was associated with fewer days with INRs greater than 3, a smaller percentage of INRs of 4 or greater, a longer time to the first INR of 4.0 or greater, and a smaller mean number of INRs per month than SM (all P.01).Initiation regimen and long-term rules that have specifically been developed and included in a computerized dosage program improve quality of anticoagulation in elderly inpatients, allowing them to benefit from a quality of care as high as that of younger ambulatory patients.

Objective: To assess the pharmacokinetics and effects on blood coagulation of dermatan sulfate (DS), a glycosaminoglycan with antithrombotic properties, following intravenous and single and repeated intramuscular administrations. The mean molecular weight of DS is currently 22kD, i.e. 5kD lower than batches used in the early development of the compound. Subjects and methods: Each of 14 male healthy volunteers received DS 300mg as an 8-hour intravenous infusion and as single and repeated (once daily for 9 days) intramuscular injections. Nine of the same subjects were also given DS 100mg and 200mg as single intramuscular doses. Plasma DS concentrations were measured with a specific chromogenic assay. Activated partial thromboplastin time (aPTT) and thrombin clotting time (TCT) responses were also determined. Results: The mean ± SD volume of distribution and terminal half-life of DS were 6.0 ± 1.4L and 0.9 ± 0.2h after intravenous infusion. Maximum plasma concentration (Cmax) and area under the plasma concentration-time curve after single intramuscular injections were dose-proportional. After repeated intramuscular administration, steady state was reached by day 3. On day 9, plasma DS fluctuated between 4.3 ± 1.5 (Cmax) and 0.9 ± 0.4 (minimum plasma concentration at steady state) mg/L, time to Cmax was 3.4 ± 0.8h, terminal half-life was 12.2 ± 4.1h and the accumulation factor was 2.0 ± 0.5. Geometric mean bioavailability of intramuscular DS was 54% and 79% after single and repeated 300mg administration, respectively. aPTT and TCT responses were both linearly related to plasma DS concentrations, with TCT showing greater responsivity. Conclusion: As compared with earlier DS studies, the present data showed a greater extent of DS absorption after single intramuscular administration and a faster absorption rate after repeated dosing, and provided evidence of dose-response predictability. These findings may explain the improved antithrombotic efficacy of DS observed in a recent clinical trial.

Besides its involvement in clot lysis, the plasminogen activator (PA) system elicits various cellular responses involved in cell migration, adhesion, and proliferation and plays a key role in the progression of cancers. beta-Catenin interacts with E-cadherins and functions as transcriptional coactivator of the Wnt-signaling pathway, which is implicated in tumor formation when aberrantly activated. We report that tissue-type plasminogen activator (tPA) elicited tyrosine phosphorylation and cytosolic accumulation of an active (non-serine-threonin phosphorylated, nonubiquitinated) form of beta-catenin in ECV304 carcinoma cells. tPA-dependent beta-catenin activation is mediated through epidermal growth factor receptor (EGFR) transactivation (via Src), suggested by the inhibitory effects of AG1478 and PP2 (specific inhibitors of EGFR and Src, respectively) and by the lack of beta-catenin activation in EGFR-negative B82 fibroblasts. EGFR phosphorylation and beta-catenin activation were inhibited by plasminogen activator inhibitor 1 and pertussis toxin, two inhibitors of the urokinase-type plasminogen activator (uPA)/uPA receptor system. beta-Catenin activation was correlated with the phosphorylation of glycogen synthase kinase-3beta through a phosphatidylinositol 3-kinase/Akt-dependent mechanism. Gel shift experiments revealed the activation of beta-catenin/T-cell-specific transcription factor (Tcf)/lymphoid enhancer factor-1 (Lef) transcriptional complex, evidenced by an increased binding of nuclear extracts to oligonucleotides containing the cyclin D1 Lef/Tcf site. beta-Catenin silencing through small interfering RNA and antisense oligonucleotides inhibited both the tPA-mediated cyclin D1 expression and cell proliferation. A similar activation of the beta-catenin pathway was triggered by amino-terminal fragment, the NH(2)-terminal catalytically inactive fragment of tPA, thus suggesting that this effect was independent of the proteolytic activity of plasminogen activators. In conclusion, the beta-catenin/Lef/Tcf pathway is activated by tPA and is involved in cell cycle progression and proliferation.

Plasminogen activators (tPA and uPA) are serine proteases that convert the circulating zymogen plasminogen to active plasmin and mediate fibrin degradation. These multifunctional proteins trigger various biological events such as extracellular matrix degradation, cell adhesion, migration, and proliferation, through not yet fully characterized mechanisms. We report that, in smooth muscle cells and ECV-304 carcinoma cells, tPA and ATF (the N-terminal catalytically inactive fragment of tPA) elicited DNA synthesis that requires activation of the sphingomyelin/ceramide/sphingosine-1-phosphate (Spm/Cer/S1P), signaling pathway and was blocked by D-erythro-2-(N-myristoylamino)-1-phenyl-propanol (D-MAPP) and N-N'-dimethyl sphingosine (DMS), two classical inhibitors of sphingosine-1-phosphate biosynthesis. Binding of tPA to its receptor uPAR triggered the coordinated activation of two key enzymes of the Spm/Cer/S1P pathway, the neutral sphingomyelinase and the sphingosine kinase-1 that was mediated by a common pertussis toxin (PTX)-sensitive mechanism. The tPA-induced sphingosine kinase-1 activation was mediated by Src, since it was inhibited by herbimycin A and in SrcK- cells (overexpressing a dominant negative kinase defective form of Src) and by ERK1/2 (early phase peaking at 15 min). Sphingosine kinase-1 activation was followed by a second phase of ERK1/2 phosphorylation (peaking at 120 min) and subsequent DNA synthesis, which were inhibited by D-MAPP and DMS, by anti-EGD-1 antibodies and in SrcK- cells (in which the mitogenic signaling was rescued by sphingosine-1-phosphate). Altogether, these data underline a pivotal role for the Spm/Cer/S1P pathway in the tPA-induced mitogenic signaling.

We report the pharmacodynamic properties of tinzaparin (175 U/kg antifactor Xa) given as a single daily administration for 5 consecutive days to 14 healthy volunteers as a known safe, effective treatment of deep vein thrombosis and pulmonary embolism. The Cmax for antifactor Xa (0.87 +/- 0.15 U/ml) was associated with a 2.4 +/- 0.5-fold prolongation of the activated partial thromboplastin time (APTT) and a high antithrombin activity (0.38 +/- 0.1 U/ml). The Cmax value of antifactor Xa was 1.5- and twofold lower than those generated by similar doses of nadroparin and enoxaparin respectively. The clearance of antifactor Xa activity (1.29 +/- 0.2 l/h) was 1.5- and twofold greater than those reported for nadroparin and enoxaparin respectively. These results indicated that the antithrombotic and prohaemorrhagic effects of a low molecular weight heparin were independent from the absolute levels of antifactor Xa activities and from the prolongation of the APTT.