Ozone-induced damage of fibrinogen molecules: identification of oxidation sites by high-resolution mass spectrometry.

Fibrinogen is highly susceptible to oxidation compared to other plasma proteins. Fibrinogen oxidation damages its structure and affects the protein function. Ozone-induced oxidative modifications of the fibrinogen Aα, Bß, and γ polypeptide chains upon addition of various amounts of the oxidiser were studied by mass spectrometry. Amino acid residues located on all three chains and main structural parts of the protein were revealed to be involved in oxidation. The αC-connector was shown to be most vulnerable to oxidation as compared to other structural parts while the E region turned out to be the most protected area of the protein. For the first time, it was established that numerous amino acid residues responsible for the conversion of fibrinogen to fibrin remain unaffected upon fibrinogen oxidation. The data obtained in this study indicate that none of the identified residues, which are considered crucial for the binding of both hole "a" and hole "b" to knob "A" and knob "B", respectively, as well as those responsible for the thrombin binding to fibrinogen E region, have been subjected to chemical alterations under moderate oxidation. The data on fibrinogen oxidation acquired in the current study enable one to assume that some of the structural fibrinogen parts and easily oxidisable residues could be endowed with antioxidant properties. New findings presented here could be essential for the detection of adaptive molecular mechanisms capable of mitigating the detrimental action of reactive oxygen species (ROS) on the functioning of oxidatively damaged fibrinogen. Data are available via ProteomeXchange with identifier PXD012046. Highlights Various oxidative modifications were detected in fibrinogen by mass spectrometry αC-connector has been shown to be most susceptible to oxidation E region proved to be least vulnerable to the action of the oxidising agent Some of the Met residues in the fibrinogen structure could operate as ROS scavengers.

Prothrombotic response to norepinephrine infusion, mimicking norepinephrine stress-reactivity effects, is partly mediated by α-adrenergic mechanisms.

BACKGROUND: Stress-induced prothrombotic changes are mediated by the sympathetic nervous system and critically involved in mental triggering of acute coronary syndromes, but the underlying psychobiology is not fully understood. We tested the hypothesis that a norepinephrine (NE) infusion to mimic effects of stress-induced NE release on blood coagulation elicits prothrombotic changes and examined to what extent these would be mediated by an alpha-adrenergic mechanism. METHODS AND RESULTS: In a single-blind placebo-controlled within-subjects design, 24 middle-aged, non-smoking, non-obese and normotensive men participated in three experimental trials with an interval between one and two weeks. Each trial applied two sequential infusions of 1 and 15 min duration with varying substances [i.e., saline as placebo, the non-specific α-blocker phentolamine (2.5 mg/min), and NE (5 µg/min)]: trial 1=saline + saline; trial 2=saline + NE, and trial 3=phentolamine + NE. Plasma levels of clotting factor VIII activity (FVIII:C), fibrinogen, and D-dimer were assessed from blood samples collected immediately before and 1 min and 20 min after infusion procedures. Compared to saline + saline, saline + NE induced increases over time in FVIII:C, fibrinogen, and D-dimer levels. With phentolamine + NE, fibrinogen levels remained increased compared to saline + saline, but changes in FVIII:C and D-dimer levels were no more different. Coagulation changes did not differ between saline + NE and phentolamine + NE. CONCLUSIONS: NE infusion activates blood coagulation. The resulting prothrombotic state could be one psychobiological mechanism underlying mental triggering of acute coronary syndromes. Blockade of α-adrenergic receptors partly attenuated NE effects on coagulation and could be implied to have preventive potential in susceptible individuals.

[Correlation between the changes of fibrinogen and the treatment effect of all-frequency sudden deafness].

Objective: To analyze the correlation between the changes of fibrinogen and the treatment effect of all-frequency sudden deafness, and to explore the individualized treatment strategy for the use of Batroxobin. Methods: Patients with all-frequency sudden deafness who were admitted to Department of Otorhinolaryngology, People's Hospital of Peking University, from January 2010 to September 2016 were selected. All patients were given standard treatment and regular use of Batroxobin. Value of fibrinogen on D1 (before treatment) / D3 / D7 (±1) and D14 (±2) were recorded, at the same time, the correlation between the changes of fibrinogen and prognosis of all-frequency sudden deafness by the audiograms of onset and after-treatment of all patients were analyzed. Independent t-test was used to analyze normal distributed measurement data and chi square linear trend test was used to analyze the curative effect of different fibrinogen groups. Results: A total of 148 patients were included, the outcomes were worst when the patient's fibrinogen was below 2 g/L or above 4 g/L before treatment, ineffective rate were both 50%. The fibrinogen was lowest when the treatment came to the third day. Normally, the patient's prognosis was best when this value waved between 0.7 and 0.9 g/L, with a total effective rate between 73.9% and 83.3%. The fibrinogen value of the 7th day was a good indicator of the outcome, and Fib7 value was significant lower in patients of effective group than ineffective ones ((1.25±0.37)g/L vs (1.38±0.35) g/L, t=-0.27, P=0.04). Patients found a best recovery when Fib7 was below 1 g/L, and the higher the Fib7 value, the higher the inefficiency (χ(2)=7.55, P=0.01). Batroxobin showed safety during the treatment and found no complications. Conclusion: The change of fibrinogen in the process of all-frequency sudden deafness is closely related to the curative effect.

Three- versus four-factor prothrombin complex concentrates for "factor-based" resuscitation in a porcine hemorrhagic shock model.

BACKGROUND: Bleeding is a leading cause of preventable death after severe injury. Prothrombin complex concentrates (PCC) treat inborn coagulation disorders and reverse oral anticoagulants, but are proposed for use in "factor-based" resuscitation strategies. Few studies exist for this indication in acidosis, or that compare 3-factor PCC (3PCC) versus 4-factor PCC (4PCC) products. We aimed to assess and compare their safety and efficacy in a porcine model of severe hemorrhagic shock and coagulopathy. METHODS: Twenty-five adult Yorkshire swine underwent 35% volume hemorrhage, ischemia-reperfusion injury, and protocolized crystalloid resuscitation. Seventeen animals were randomized at 4 hours after model creation to receive a 45-IU/kg dose of either 3PCC or 4PCC. An additional eight animals received autologous plasma transfusion before 4PCC to better characterize response to PCC. Individual factor levels were drawn at 4 hours and 6 hours. RESULTS: The model created significant acidosis with mean pH of 7.21 and lactate of 9.6 mmol/L. After PCC, 66.7% of 3PCC animals and 25% of 4PCC animals (regardless of plasma administration) developed consumptive coagulopathy. The animals that developed consumptive coagulopathy had manifested the "lethal triad" with lower temperatures (36.3°C vs. 37.8°C), increased acidosis (pH, 7.14 vs. 7.27; base excess, -12.1 vs. -6.5 mEq/L), and worse coagulopathy (prothrombin time, 17.1 vs. 14.6 seconds; fibrinogen, 87.9 vs. 124.1 mg/dL) (all p < 0.05). In the absence of a consumptive coagulopathy, 3PCC and 4PCC improved individual clotting factors with transient improvement of prothrombin time, but there was significant depletion of fibrinogen and platelets with no lasting improvement of coagulopathy. CONCLUSION: PCC failed to correct coagulopathy and was associated with fibrinogen and platelet depletion. Of greater concern, PCC administration resulted in consumptive coagulopathy in the more severely ill animals. The incidence of consumptive coagulopathy was markedly increased with 3PCC versus 4PCC, and these products should be used with caution in this setting.

α-1 Antitrypsin Enhances Islet Engraftment by Suppression of Instant Blood-Mediated Inflammatory Reaction.

Islet cell transplantation has limited effectiveness because of an instant blood-mediated inflammatory reaction (IBMIR) that occurs immediately after cell infusion and leads to dramatic ß-cell death. In intraportal islet transplantation models using mouse and human islets, we demonstrated that α-1 antitrypsin (AAT; Prolastin-C), a serine protease inhibitor used for the treatment of AAT deficiency, inhibits IBMIR and cytokine-induced inflammation in islets. In mice, more diabetic recipients reached normoglycemia after intraportal islet transplantation when they were treated with AAT compared with mice treated with saline. AAT suppressed blood-mediated coagulation pathways by diminishing tissue factor production, reducing plasma thrombin-antithrombin complex levels and fibrinogen deposition on islet grafts, which correlated with less graft damage and apoptosis. AAT-treated mice showed reduced serum tumor necrosis factor-α levels, decreased lymphocytic infiltration, and decreased nuclear factor (NF)-κB activation compared with controls. The potent anti-inflammatory effect of AAT is possibly mediated by suppression of c-Jun N-terminal kinase (JNK) phosphorylation. Blocking JNK activation failed to further reduce cytokine-induced apoptosis in ß-cells. Taken together, AAT significantly improves islet graft survival after intraportal islet transplantation by mitigation of coagulation in IBMIR and suppression of cytokine-induced JNK and NF-κB activation. AAT-based therapy has the potential to improve graft survival in human islet transplantation and other cellular therapies on the horizon.

Equiosmolar Solutions of Hypertonic Saline and Mannitol Do Not Impair Blood Coagulation During Elective Intracranial Surgery.

BACKGROUND: The authors investigated the effect of equiosmolar, equivolemic solutions of 3% hypertonic saline (HS) and 20% mannitol on blood coagulation assessed by rotational thromboelastometry (ROTEM) and standard coagulation tests during elective craniotomy. METHODS: In a prospective, randomized, double-blind trial, 40 patients undergoing elective craniotomy were randomized to receive 5 mL/kg of either 20% mannitol or 3% HS for intraoperative brain relaxation. Fibrinogen, activated partial thromboplastin time, prothrombin time, hemoglobin, hematocrit, and platelet count were simultaneously measured intraoperatively with ROTEM for EXTEM, INTEM, and FIBTEM analysis. ROTEM parameters were: clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF), and α-angle. RESULTS: No significant differences between groups were found in ROTEM variables CT, CFT, MCF, α-angle (EXTEM and INTEM), and MCF (FIBTEM) nor standard coagulation tests. ROTEM parameters did not show changes after administration of hyperosmolar solutions relating to basal values, except for an increase of CFT EXTEM (118±28 vs. 128±26 s) and decrease of CT INTEM (160±18 vs. 148±15 s) with values within normal range. Significant decreases from baseline levels were observed for hematocrit (-7%), platelet count (-10%), and fibrinogen (-13%) after HS infusion, and hematocrit (-9%), platelet count (-13%), and fibrinogen (-9%) after mannitol infusion, but remaining normal. CONCLUSIONS: The use of 5 mL/kg of equiosmolar solutions of 3% HS and 20% mannitol applied to reach a brain relaxation during elective craniotomy does not induce coagulation impairment as evidenced by ROTEM and standard coagulation tests.

Resveratrol more effectively than quercetin reduces endothelium degeneration and level of necrosis factor α in patients with coronary artery disease.

INTRODUCTION: endothelial dysfunction (ED) is one of the most important links in the pathogenesis of atherosclerosis (ASVD) - morphological basis of coronary artery disease (CAD). OBJECTIVE: to study the effect of polyphenolic antioxidants, resveratrol and quercetin, on endothelial degeneration factors in CAD patients. MATERIALS AND METHODS: the study involved 93 patients with coronary artery disease: stable angina pectoris, FC II. The cytofluorometric technique was applied to define the level of circulating endothelial microparticles (EMP) CD32+CD40+ in peripheral blood in order to identify ED. The content of tumor necrosis factor α (TNF-α), fibrinogen, hemocoagulation and lipid profile parameters were being determined in the blood, as well. Patients were divided into 3 groups. Basic therapy (ß-blockers, statins, aspirin) was prescribed to 33 persons of the comparison group, patients of the study group 1 (30 persons) additionally received resveratrol at a dose of 100 mg daily, patients of the study group 2 (30 persons) got quercetin at a dose of 3 g per day. In 2 months, the second examination of the patients was performed in the amount indicated. RESULTS: under the influence of resveratrol a significant reduction of the level of TNF-α and the number of EMP in peripheral blood was shown, in contrast to the results of other study groups. All groups showed a decrease in total cholesterol and low-density lipoprotein cholesterol, statistical differences between data of groups were not found. Indicators of coagulogramma in all study groups did not change significantly, however, there was a statistically significant reduction of fibrinogen in the blood. CONCLUSIONS: resveratrol, unlike quercetin, has a positive effect on the endothelial function and systemic inflammation, which may be the result of its influence on intracellular molecular cascades associated with the nuclear transcription factor of NF-kB.

Short fungal fractions of ß-1,3 glucans affect platelet activation.

Platelets are capable of binding, aggregating, and internalizing microorganisms, which enhances the elimination of pathogens from the blood. The yeast Candida albicans is a pathobiont causing life-threatening invasive infections. Its cell wall contains ß-1,3 glucans that are known to trigger a wide range of host cell activities and to circulate during infection. We studied the effect of ß-1,3 glucan fractions (BGFs) consisting of diglucosides (Glc2), tetraglucosides (Glc4), and pentaglucosides (Glc5) on human platelets, their mechanisms of action, and their possible impact on host defenses. The effect of BGFs on the coagulation process was determined by measuring thrombin generation. Platelets pretreated with BGFs were analyzed in terms of activation, receptor expression, aggregation, and adhesion to neutrophils and to C. albicans The results show that BGFs affected the endogenous thrombin potential in a concentration-dependent manner. For platelet activation, BGFs at a low concentration (2 µmol/l) reduced ATP release and prevented the phosphorylation of protein kinase C. BGFs diminished the expression of P-selectin and the activation of αIIbß3 BGFs decreased platelet aggregation and the interaction between thrombin-stimulated platelets and neutrophils, fibrinogen, and C. albicans GLc5 decreased ATP release and TGF-ß1 production in response to TLR4 upregulation in thrombin-stimulated platelets, but TLR4 blockage abolished the effect of BGFs on platelets. This study provides evidence that fungal pentaglucosides modulate platelet activity mediated via TLR4 stimulation and reduce platelet-neutrophil interaction.

Effect of Iron and Carbon Monoxide on Fibrinogenase-like Degradation of Plasmatic Coagulation by Venoms of Six Agkistrodon Species.

Annually, thousands suffer poisonous snakebite, often from defibrinogenating species. It has been demonstrated that iron and carbon monoxide change the ultrastructure of plasma thrombi and improve coagulation kinetics. Thus, this investigation sought to determine whether pre-treatment of plasma with iron and carbon monoxide could attenuate venom-mediated catalysis of fibrinogen obtained from Agkistrodon species with fibrinogenase activity. Human plasma was pre-treated with ferric chloride (0-10 µM) and carbon monoxide-releasing molecule-2 (CORM-2, 0-100 µM) prior to exposure to 0.5-11 µg/ml of six different Agkistrodon species' venom. The amount of venom used for experimentation needed to decrease coagulation function of one or more kinetic parameters by at least 50% of normal values for (e.g. half the normal speed of clot formation). Coagulation kinetics were determined with thrombelastography. All six snake venoms degraded plasmatic coagulation kinetics to a significant extent, especially prolonging the onset to clot formation and diminishing the speed of clot growth. Pre-treatment of plasma with iron and carbon monoxide attenuated these venom-mediated coagulation kinetic changes in a species-specific manner, with some venom effects markedly abrogated while others were only mildly decreased. Further in vitro investigation of other pit viper venoms that possess fibrinogenolytic activity is indicated to identify species amenable to or resistant to iron and carbon monoxide-mediated attenuation of venom-mediated catalysis of fibrinogen. Lastly, future pre-clinical investigation with animal models (e.g. rabbit ear-bleed model) is planned to determine whether iron and carbon monoxide can be used therapeutically after envenomation.

Impact on hepatic estrogen-sensitive proteins by a 1-year contraceptive vaginal ring delivering Nestorone® and ethinyl estradiol.

OBJECTIVES: Estrogen-sensitive hepatic proteins were assessed in women using a contraceptive vaginal ring (CVR) delivering 150mcg Nestorone® (NES) and 15mcg ethinyl estradiol (EE). STUDY DESIGN: A substudy of the Contraceptive Clinical Trials Network of the National Institute of Child Health and Human Development enrolled 129 participants, with assessments of factor VIII, fibrinogen, protein S (PS) and sex hormone binding globulin (SHBG). Thirty-six participants had used combined hormonal contraceptives (CHCs) in the cycle preceding first CVR use (recent users) and 70 had no history of recent use (nonusers). RESULTS: Mean values at baseline were within the normal range for all four proteins but were higher for factor VIII, fibrinogen and SHBG and significantly lower for PS in recent compared to nonusers. During NES/EE CVR use, factor VIII, fibrinogen and PS were within the normal range; however, SHBG levels were increased by nearly 100% at Cycle 13. The change from baseline to final evaluation was statistically significant for all proteins in nonusers. The change in recent users was significant for factor VIII at Cycle 6 and for SHBG at Cycles 6 and 13, but not for PS or fibrinogen. CONCLUSION: NES/EE CVR for up to 13cycles was associated with changes from baseline in plasma levels of factor VIII, fibrinogen and PS that were within the normal range, with SHBG levels above the normal range by Cycle 6. Nonusers of CHC before CVR showed wider changes in values versus recent users whose baseline values were increased by previous EE exposure. IMPLICATIONS: Recent use of CHCs demonstrated significant changes in all four measured hepatic proteins at baseline compared to nonusers. Use of the NES/EE CVR further changed these hepatic protein markers, but values remained within the normal range. Prebaseline exposure to estrogen can obscure interpretation of hepatic proteins changes associated with a second CHC.

Synthesis and biological evaluation of methylated scutellarein analogs based on metabolic mechanism of scutellarin in vivo.

Scutellarin (1) could be hydrolyzed into scutellarein (2) in vivo and then converted into methylated, sulfated and glucuronidated forms. In order to investigate the biological activities of these methylated metabolites, eight methylated analogs of scutellarein (2) were synthesized via semi-synthetic methods. The antithrombotic activities of these compounds were evaluated through the analyzation of prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and fibrinogen (FIB). Their antioxidant activities were assessed by measuring their scavenging capacities toward 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and the ability to protect PC12 cells against H2O2-induced cytotoxicity. Furthermore, the physicochemical properties of these compounds including aqueous solubility and lipophilicity were also investigated. The results showed that 6-O-methylscutellarein (5) demonstrated potent antithrombotic activity, stronger antioxidant activity and balanced solubility and permeability compared with scutellarin (1), which warrants further development of 5 as a promising lead for the treatment of ischemic cerebrovascular disease.

Steroid therapy attenuates acute phase reactant response among children on ventricular assist device support.

BACKGROUND: Hyperfibrinogenemia, which can create a procoagulant milieu, is frequently observed in patients supported with the Berlin EXCOR (Berlin Heart GmbH, Berlin, Germany) ventricular assist device (VAD). We began initiating corticosteroids in patients with systemic inflammatory response syndrome (SIRS) episodes to mitigate hyperfibrinogenemia. We set forth to describe the impact of corticosteroids on the hyperfibrinogenemic state in our institutional experience. METHODS: Retrospective data was collected on 44 consecutive patients implanted with the Berlin EXCOR VAD from April 15, 2005 through May 6, 2013. Pertinent information was abstracted from the electronic medical record. The reduction of C-reactive protein (CRP) and fibrinogen levels among days from corticosteroid treatment were described. Infections and insulin use were reported based on whether patients received steroids and if steroids were given for SIRS. RESULTS: Over the initial 44 Berlin EXCOR VAD implantations, 14 patients were treated with 21 courses of corticosteroids for SIRS episodes as identified by clinical features and rise in CRP. Treatment with corticosteroids reduced fibrinogen levels by day 2 to a statistically significant degree (p = 0.008). No difference in hyperglycemia or infections occurred among patients receiving corticosteroids for SIRS. CONCLUSIONS: Treatment with corticosteroids can potentially mitigate the SIRS response among children supported on the Berlin EXCOR VAD. In patients who received corticosteroids to mitigate inflammation, there was no increase in infections or hyperglycemia requiring insulin administration compared with patients who did not receive steroids.

Patients with prostate cancer treated by ADT have significantly higher fibrinogenemia than healthy control.

PURPOSE: Androgen deprivation therapy (ADT) for prostate cancer (PCa) may increase peripheral insulin resistance, induce type 2 diabetes, change body composition, and alter lipoprotein profile. Some studies have reported an association between ADT and increased risk of cardiovascular events. It is known that serum level of fibrinogen (SF) is associated with coronary artery disease and increased cardiovascular risk (CVR). The aim of this study is to determine the increase in SF and C-reactive protein (CRP) of PCa patients on ADT. METHODS: Ninety-seven patients with locally advanced PCa (study group) were analyzed [mean age 73.4 years ± 6.3 SD, mean prostate specific antigen (PSA) 15.4 ng/ml ± 7.5 SD]. They were examined with blood chemistry including serum cholesterol (CHL), high density lipoproteins (HDL), low density lipoproteins (LDL), very low density lipoproteins, triacylglycerol (TAG), serum fibrinogen (FB), CRP and serum fasting glucose (SFG), serum testosterone, free testosterone at baseline, and after 12 months of ADT. RESULTS: Patients after 12 months of ADT (study group) had significantly higher overall serum CHL (p < 0.001), higher LDL (p = 0.01), higher FB (p < 0.001), higher serum SFG (p = 0.03) in comparison with the control group. Increase in HDL (p = 0.245) and CRP (p = 0.1) was not significant. Two patients from the study group were diagnosed with new-onset diabetes. CONCLUSIONS: This is the first study that demonstrates the significant increase in FB in PCa patients on ADT, while CRP as inflammatory marker did not increase. Elevation of SF may contribute to increased CVR in PCa patients. Further prospective studies are warranted to confirm this association.

Cryoprecipitate transfusion: assessing appropriateness and dosing in trauma.

BACKGROUND: Originally developed for patients with congenital factor VIII deficiency, cryoprecipitate is currently largely used for acquired hypofibrinogenemia in the context of bleeding. However, scant evidence supports this indication and cryoprecipitate is commonly used outside guidelines. In trauma, the appropriate cryoprecipitate dose and its impact on plasma fibrinogen levels are unclear. OBJECTIVES: The aims were to evaluate (i) the appropriateness of cryoprecipitate transfusion in trauma and (ii) the plasma fibrinogen response to cryoprecipitate transfusion during massive transfusion in trauma. METHODS: Retrospective review (January 1998-June 2008) of indications, dose and plasma fibrinogen response to cryoprecipitate transfusion at a large teaching hospital. A fibrinogen of <1.0 g L(-1) within 2 and 6 h of transfusion was used for evaluating appropriateness. RESULTS: Ten thousand five hundred and forty cryoprecipitate units were transfused in 1004 patients. Thirty-seven percent and 31% were used in cardiac surgery and trauma, respectively. In 394 events in trauma, 238 (60%) and 259 (66%) were considered appropriate using the 2- and 6-h cut-off criteria, respectively. In patients who did not receive plasma components 2 h prior to cryoprecipitate, a dose of 8.7 (± 1.7) units caused a mean increase in fibrinogen levels of 0.55 (± 0.24) g L(-1), or 0.06 g L(-1) per unit. CONCLUSIONS: In our hospital, where transfusion guidelines are overseen by transfusion medicine specialists and technologists, and policies for rapid blood component and laboratory turnaround times exist, it is possible to achieve high rates of appropriateness for cryoprecipitate transfusion in trauma. The current recommended dose causes a modest increase in fibrinogen levels (0.55 g L(-1) ).

Anti-platelet effects of olive oil extract: in vitro functional and proteomic studies.

PURPOSE: Platelets play a key role in haemostasis and wound healing, contributing to formation of vascular plugs. They are also involved in formation of atherosclerosic plaques. Some traditional diets, like the Mediterranean diet, are associated with a lower risk of cardiovascular disease. Components in these diets may have anti-platelet functions contributing to their health benefits. METHODS: We studied the effects of alperujo extract, an olive oil production waste product containing the majority of polyphenols found in olive fruits, through measurement of effects on platelet aggregation and activation in isolated human platelets, and through identification of changes in the platelet proteome. RESULTS: Alperujo extract (40 mg/L) significantly decreased in vitro ADP- (p = 0.002) and TRAP- (p = 0.02) induced platelet activation as measured by the flow cytometry using the antibody for p-selectin (CD62p), but it did not affect the conformation of the fibrinogen receptor as measured by flow cytometry using the antibodies for anti-fibrinogen, CD42a and CD42b. Alperujo extract (100 mg/L) inhibited both collagen- and TRAP-induced platelet aggregation by 5% (p < 0.05), and a combination of hydroxytyrosol and 3,4-dihydroxyphenylglycol were, at least partly, responsible for this effect. Proteomic analysis identified nine proteins that were differentially regulated by the alperujo extract upon ADP-induced platelet aggregation. These proteins represent important mechanisms that may underlie the anti-platelet effects of this extract: regulation of platelet structure and aggregation, coagulation and apoptosis, and signalling by integrin αIIb/ß3. CONCLUSIONS: Alperujo extract may protect against platelet activation, platelet adhesion and possibly have anti-inflammatory properties.

Characteristics of prion-filtered red cells suspended in pathogen-inactivated plasma (MB treated or solvent-detergent treated) for neonatal exchange transfusion.

BACKGROUND AND OBJECTIVES: Neonates undergoing exchange transfusion require <5-day-old red cells suspended in plasma. This study assesses the effect of replacing the saline, adenine, glucose and mannitol (SAGM) of prion reduced (P-Capt) red cells with either methylene blue-treated plasma (MBTFFP) or OctaplasLG to reduce the risk of variant Creutzfelt-Jakob disease transmission. MATERIALS AND METHODS: Twenty leucoreduced red cell units in SAGM were prion reduced on day 1. The SAGM was replaced by MBTFFP (n=10) or OctaplasLG (n=10). The units were irradiated and stored at 4°C for 24 h. A further 20 units were stored for 5 days before being processed as above. Haemolysis (%), potassium, ATP, 2,3-DPG and plasma proteins were measured. RESULTS: Haemolysis remained low (≤0·16%). Following irradiation and storage, red cells in both types of plasma showed similar changes in potassium and ATP concentrations. The 2,3-DPG concentrations were well maintained although lower in red cells in OctaplasLG compared with those in MBTFFP (4·79 vs. 6·83 µmoles/g Hb on day 6). MBTFFP contained lower concentrations of fibrinogen, FV and FVIII. In OctaplasLG, alpha-2-antiplasmin was approximately 0·4 U/ml lower than in MBTFFP. After 24 h at 4°C, free protein S in OctaplasLG fell from 0·82 to 0·57 IU/ml. Other plasma proteins, in both types of plasma, were stable. CONCLUSIONS: Red cells in both types of plasma demonstrated similar storage characteristics. The plasma proteins, except protein S in OctaplasLG, were stable over 24 h at 4°C in both types of plasma, and low FVIII concentrations were noted in the MBTFFP (group O) units used.

[Evaluation of haemostasis in children treated with valproic acid]. / Untersuchungen zur Hämostase bei Kindern unter Valproatbehandlung.

UNLABELLED: Coagulation parameters were determined in children with valproic acid mono- and valproic acid-lamotrigin combination therapy. PATIENTS, METHODS: Monotherapy group (n = 22; mean age: 10.5 years) was compared to combination therapy (n = 7; 12.9 years) and a control group (n = 22; 8.7 years). The following parameters were measured: aggregation and ATP-release in whole blood (ADP: 20 µmol/l, collagen: 1 µg/ml, thrombin: 0.5 U/ml), PFA-100® closure times (CT), blood cell counts, global tests, VWF:Ag, VWF:CBA, factors VIII and XIII as well as fibrinogen. Bleeding symptoms were evaluated by using a questionnaire. RESULTS: For ADP- and collagen-induced aggregation as well as for ATP release no significant differences between the groups were detected. The combined therapy group showed significantly prolonged CT. Von Willebrand disease was not detected in any of the patients. The platelet count was significantly decreased in the monotherapy group. In six children a mild bleeding tendency was observed, mostly epistaxis. CONCLUSION: A clinically relevant influence of valproic acid on haemostasis was found only in few cases. However, before surgical procedures an extended coagulation diagnostics is recommended in patients with valproic acid therapy.

Impacto del tratamiento con bezafibrato en pacientes con hiperfibrinogenemia e infarto agudo del miocardio con elevación del ST / Impact of bezafibrate treatment in patients with hyperfibrinogenemia and ST-elevation acute myocardial infarction: a randomized clinical trial

Introducción: La hiperfibrinogenemia se considera predictora de eventos cardiovasculares en sujetos sanos y pacientes con cardiopatía isquémica. Como medida de prevención primaria, el bezafibrato disminuye el fibrinógeno sanguíneo y los eventos cardiovasculares, pero su efecto en el síndrome coronario agudo aún no se conoce. Material y métodos: Ensayo clínico, aleatorizado, controlado con tratamiento convencional. Se incluyeron pacientes con infarto agudo del miocardio con elevación del segmento ST y concentraciones de fibrinógeno > 500 mg/dl a las 72 horas de evolución. Se asignaron a recibir 400 mg de bezafibrato (grupo I) o tratamiento convencional (grupo II). Punto primario de evaluación: concentraciones de fibrinógeno; puntos secundarios: recurrencia de angina o infarto, falla ventricular izquierda y puntos finales combinados durante la estancia hospitalaria. Resultados: Se incluyeron 25 pacientes por grupo. Las concentraciones de fibrinógeno al egreso hospitalario fueron significativamente menores en el grupo I (532.42 ± 129.6 versus 889 ± 127.32 mg/dl del grupo II, p < 0.0001). Los puntos secundarios se presentaron con mayor frecuencia en el grupo II que en el grupo I: angina (56 versus 4%, riesgo relativo 0.071 [0.010-0.503], p < 0.0001), falla ventricular (24 versus 4%, riesgo relativo 0.167 [0.022-1.286], p = 0.049) y puntos finales combinados (76 versus 8%, riesgo relativo 0.105 [0.027- 0.405], p < 0.001). Conclusiones: El tratamiento con bezafibrato fue seguro y logró reducir el fibrinógeno en pacientes con infarto agudo. Esta reducción se asoció con menor frecuencia de eventos cardiovasculares a corto plazo.

BACKGROUND: Hyperfibrinogenemia is a predictor of cardiovascular events in healthy subjects and in patients with chronic ischemic heart disease. Bezafibrate decreases fibrinogen levels and also the incidence of major cardiovascular events in primary prevention, but its effects in acute coronary syndrome are unknown. METHODS: This is a randomized, controlled clinical trial with conventional therapy. We included patients with Acute ST Elevation Myocardial Infarction (STEAMI) and fibrinogen concentration >500 mg/dl at 72 h of evolution. We randomized subjects into two groups: bezafibrate 400 mg (group I) and conventional therapy (group II). Primary end point was decrease of fibrinogen concentrations. Secondary end points were recurrence of angina or infarction, left ventricular failure and combined end points during hospitalization. RESULTS: We included 25 patients in each group. Fibrinogen concentrations were lower at hospital discharge in Group I than in Group II (532.42 +/- 129.6 vs. 889 +/- 127.32 mg/dl in group II, p <0.0001). Secondary end points were more frequent in Group II than in Group I: angina (56% vs. 4%, RR 0.071 [0.010-0.503], p <0.0001), left ventricular failure (24% vs. 4%, RR 0.167 [0.022-1.286], p = 0.049) and combined end points (76% vs. 8%, RR 0.105 [0.027-0.405], p <0.001). CONCLUSIONS: Bezafibrate treatment was a safe treatment and reduced fibrinogen levels in patients with STEAMI and hyperfibrinogenemia. In the short term, this reduction was associated with a lower incidence of major cardiovascular events.

Rosiglitazone reduces plasma levels of inflammatory and hemostatic biomarkers and improves global endothelial function in habitual heavy smokers without diabetes mellitus or metabolic syndrome.

BACKGROUND/PURPOSE: Thiazolidinediones have anti-atherothrombotic effects in diabetic patients. However, the effects of rosiglitazone on inflammatory and hemostatic markers, as well as global endothelial function in non-diabetic smokers are unknown. METHODS: Twenty-seven healthy male heavy smokers without metabolic syndrome were enrolled in this double-blind, controlled study. Fourteen subjects received 4 mg/day rosiglitazone for 8 weeks (group R) and 13 subjects received placebo (group C). Changes in the reflection index (Delta RI) of beta-agonist-induced endothelium-dependent vasodilatation by photoplethysmography and plasma biomarkers were measured before and after treatment. RESULTS: Matrix metalloproteinase-9, fibrinogen, and high-sensitivity C-reactive protein were reduced significantly in group R after treatment as compared with the baseline [84.1 (45.6 139.0) vs. 123.9 (58.4 141.8) ng/mL, p = 0.03; 2914 (2400-3553) vs. 3220 (2542-3940) mg/L, p = 0.04; and 3.4 (2.2 5.1) vs. 5.5 (4.1 6.8) mg/L, p = 0.009, respectively]. Delta RI was improved markedly in group R as compared with the baseline [13.5 (4.2 65.1) vs. 2.5 (-10.6 to 9.3)%; p = 0.024]. These biomarkers and Delta RI did not differ significantly in the group C. There were no significant changes in fasting plasma glucose, insulin, homeostasis model assessment index, and lipid profile in both groups R and group C. CONCLUSION: Rosiglitazone significantly reduces plasma levels of inflammatory and hemostatic biomarkers, and restores global endothelial dysfunction, independently from insulin sensitization, in healthy smokers.

Fibrinogen kinetics and protein turnover in obese non-diabetic males: effects of insulin.

BACKGROUND: Although hyperfibrinogenemia and insulin resistance are common in obesity and diabetes mellitus, the impact of obesity per se on fibrinogen turnover and the insulin effects on fibrinogen and protein kinetics is unknown. METHODS: We measured fibrinogen and albumin fractional (FSR) and absolute (ASR) synthesis rates, as well as protein turnover, in non-diabetic, obese and in control male subjects both before and following an euglycemic, euaminoacidemic, hyperinsulinemic clamp, using L-[(2)H(3)]-Leucine isotope infusion. RESULTS: In the obese, basal fibrinogen concentrations was approximately 25% greater (p < 0.035), and fibrinogen pool approximately 45% greater (p < 0.005), than in controls. Both FSR and ASR of fibrinogen were similar to control values. With hyperinsulinemia, although fibrinogen FSR and ASR were not significantly modified with respect to baseline in either group, fibrinogen ASR resulted to be approximately 50% greater in the obese than in controls (p < 0.015). Hyperinsulinemia equally stimulated albumin synthesis and suppressed leucine appearance from endogenous proteolysis in both groups. Amino acid clearance was also similar. In the obese, the insulin-mediated glucose disposal was approximately 50% lower (p < 0.03) than in controls, and it was inversely correlated with fibrinogen ASR during the clamp in both groups (r = - 0.58). CONCLUSIONS: In obese, non-diabetic males, post absorptive fibrinogen production is normal. Whole-body amino acid disposal, basal and insulin-responsive protein degradation, and albumin synthesis are also normal. However, the greater fibrinogen ASR in the obese with hyperinsulinemia, and the inverse relationship between insulin sensitivity and clamp fibrinogen production, suggest a role for hyperinsulinemia and/or insulin resistance on fibrinogen production in obesity.