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Sample records for prothrombin complex concentrates

  1. Clinical review: Prothrombin complex concentrates - evaluation of safety and thrombogenicity

    PubMed Central

    2011-01-01

    Prothrombin complex concentrates (PCCs) are used mainly for emergency reversal of vitamin K antagonist therapy. Historically, the major drawback with PCCs has been the risk of thrombotic complications. The aims of the present review are to examine thrombotic complications reported with PCCs, and to compare the safety of PCCs with human fresh frozen plasma. The risk of thrombotic complications may be increased by underlying disease, high or frequent PCC dosing, and poorly balanced PCC constituents. The causes of PCC thrombogenicity remain uncertain but accumulating evidence indicates the importance of factor II (prothrombin). With the inclusion of coagulation inhibitors and other manufacturing improvements, today's PCCs may be considered safer than earlier products. PCCs may be considered preferable to fresh frozen plasma for emergency anticoagulant reversal, and this is reflected in the latest British and American guidelines. Care should be taken to avoid excessive substitution with prothrombin, however, and accurate monitoring of patients' coagulation status may allow thrombotic risk to be reduced. The risk of a thrombotic complication due to treatment with PCCs should be weighed against the need for rapid and effective correction of coagulopathy. PMID:21345266

  2. Prothrombin Complex Concentrate Reduces Blood Product Utilization in Heart Transplantation.

    PubMed

    Enter, Daniel H; Zaki, Anthony L; Marsh, Megan; Cool, Nikki; Kruse, Jane; Li, Zhi; Andrei, Adin-Cristian; Iddriss, Adam; McCarthy, Patrick M; Malaisrie, S Chris; Anderson, Allen; Rich, Jonathan D; Pham, Duc Thinh

    2017-08-22

    Current practices for the reversal of warfarin prior to cardiac surgery include the use of vitamin K and fresh frozen plasma (FFP) to reduce the risk of bleeding. Although the 2010 International Society of Heart and Lung Transplantation guidelines acknowledge the use of PCC (Prothrombin Complex Concentrate), there is no clear consensus on its efficacy. The objective of this study was to assess the efficacy of 4-factor Prothrombin Complex Concentrate (4-F PCC) administration in patients requiring warfarin reversal prior to heart transplantation by determining blood product utilization perioperatively. Twenty-one patients who received 4-F PCC for warfarin reversal prior to heart transplantation were compared to a similar cohort of 39 patients who did not receive 4-F PCC from January 2011 to July 2015. Blood product utilization was collected retrospectively for the 24-hour preoperative, intraoperative, and 48-hour postoperative periods. Patients receiving 4-F PCC required fewer blood products in all 3 time periods. In the 24-hour preoperative period, 22 patients (56%) in the control group and 2 patients (10%) in the 4-F PCC groups received blood products (p<0.001). Intraoperatively, all patients received blood products. The 4-F PCC group required fewer units of packed red blood cells (median 3 vs. 7 units, p<0.001) and FFP (median 4 vs. 9 units, p<0.001). In the 48-hour postoperative period, 20 patients (51%) in the control group and 5 patients (24%) in the 4-F PCC group received blood products (p=0.04). 4-F PCC is associated with reduced blood product utilization 24 hours preoperatively and intraoperatively. Historically, the majority of patients require FFP for warfarin reversal preoperatively. In this single-center study, a significant reduction in the need for FFP was demonstrated with the use of 4-F PCC. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  3. Biochemical characterization of prothrombin complex concentrates in China.

    PubMed

    Cao, Haijun; Tian, Qian; Huang, Yun; Ye, Shengliang; Xin, Ye; Lin, Fangzhao; Li, Changqing

    2015-03-01

    Despite increasing use of prothrombin complex concentrates (PCCs), there is little knowledge about the biochemical characterization of Chinese PCCs. Six Chinese PCCs were investigated and compared with PCCs (Octaplex®) from Europe. The levels of coagulation factors and inhibitors were detected. The presence of activated coagulation factors was assessed. Furthermore, their thrombin inhibitory capacities, specific activity and purity were assayed. All above parameters of biochemical properties were statistically analyzed. Chinese PCCs contained FⅡ, Ⅶ, Ⅸ and Ⅹ, protein C, S and Z, heparin and extremely low level antithrombin, as well as Octaplex®. The measured FⅨ activities were similar to those declared, however the measured potency of FⅡ, Ⅶ and Ⅹ greatly exceeded the labeled. Though all preparations were negative for activated coagulation factors in non-activated partial thromboplastin time test, the activated coagulation factor Ⅶ (FⅦa) remained in all PCCs and its content differed greatly. Overall, FⅦa content of Chinese PCCs was higher than that of Octaplex®. Further, Chinese PCCs were inferior to Octaplex® in the thrombin inhibitory capacities, specific activity and purity. In summary, compared with Octaplex®, Chinese PCCs' errors about the labeled activity of coagulation factors and probably high risks of thrombosis should be considered.

  4. Fibrinogen and prothrombin complex concentrate in trauma coagulopathy.

    PubMed

    Hannon, Matthew; Quail, Jacob; Johnson, Matthew; Pugliese, Cara; Chen, Kejian; Shorter, Heidi; Riffenburgh, Robert; Jackson, Ronald

    2015-06-15

    Coagulopathy after injury contributes to hemorrhage and death. Treatment with specific coagulation factors could decrease hemorrhage and mortality. Our aim was to compare fibrinogen and prothrombin complex concentrate (PCC) in a rabbit model of hemorrhagic shock. New Zealand white rabbits were anesthetized. Blood was withdrawn to a mean arterial pressure (MAP) of 30-40 mm Hg for 30 min. Animals were resuscitated with lactated Ringer to a MAP of 50-60 mm Hg and randomized to receive 100 mg/kg of fibrinogen, PCC 25 IU/kg, or lactated Ringer. A liver injury was created. A MAP of 50-60 mm Hg was maintained for 60 min. The primary outcome was blood loss, and secondary outcomes were fluid administered and coagulopathy as measured by plasma-based tests. There were eight animals in each group. Median blood loss was significantly higher in the fibrinogen group, at 122 mL (95% confidence interval [CI], 75-194), when compared with that in the control group, 35 mL (95% CI, 23-46; P value = 0.001), and the PCC group, 26 mL (95% CI, 4-54; P value = 0.002). Resuscitation fluid requirement was highest in the fibrinogen group, at 374 mL (95% CI, 274-519), and lowest in the PCC group, at 238 mL (95% CI, 212-309) (P = 0.01). Plasma-based coagulation tests were not different among groups. In a rabbit model, PCC did not have a significant effect on blood loss. Fibrinogen increased blood loss and fluid requirements. Published by Elsevier Inc.

  5. The role of prothrombin complex concentrates in reversal of target specific anticoagulants.

    PubMed

    Babilonia, Katrina; Trujillo, Toby

    2014-01-01

    Over the past several years a new era for patients requiring anticoagulation has arrived. The approval of new target specific oral anticoagulants offers practitioners several advantages over traditionally used vitamin K antagonist agents including predictable pharmacokinetics, rapid onset of action, comparable efficacy and safety, all without the need for routine monitoring. Despite these benefits, hemorrhagic complicates are inevitable with any anticoagulation treatment. One of the major disadvantages of the new oral anticoagulants is lack of specific antidotes or reversal agents for patients with serious bleeding or need for urgent surgery. As use of the new target specific oral anticoagulants continues to increase, practitioners will need to understand both the pharmacodynamics and pharmacokinetic properties of the agents, as well as, the available literature with use of non-specific therapies to reverse anticoagulation. Four factor prothrombin complex concentrates have been available for several years in Europe, and recently became available in the United States with approval of Kcentra. These products have shown efficacy in reversing anticoagulation from vitamin K antagonists, however their usefulness with the new target specific oral anticoagulants is poorly understood. This article will review the properties of dabigatran, rivaroxaban and apixaban, as well as the limited literature available on the effectiveness of prothrombin complex concentrates in reversal of their anticoagulant effects. Additional studies are needed to more accurately define the role of prothrombin complex concentrates in patients with life threatening bleeding or who require emergent surgery, as current data is both limited and conflicting.

  6. The role of prothrombin complex concentrates in reversal of target specific anticoagulants

    PubMed Central

    2014-01-01

    Over the past several years a new era for patients requiring anticoagulation has arrived. The approval of new target specific oral anticoagulants offers practitioners several advantages over traditionally used vitamin K antagonist agents including predictable pharmacokinetics, rapid onset of action, comparable efficacy and safety, all without the need for routine monitoring. Despite these benefits, hemorrhagic complicates are inevitable with any anticoagulation treatment. One of the major disadvantages of the new oral anticoagulants is lack of specific antidotes or reversal agents for patients with serious bleeding or need for urgent surgery. As use of the new target specific oral anticoagulants continues to increase, practitioners will need to understand both the pharmacodynamics and pharmacokinetic properties of the agents, as well as, the available literature with use of non-specific therapies to reverse anticoagulation. Four factor prothrombin complex concentrates have been available for several years in Europe, and recently became available in the United States with approval of Kcentra. These products have shown efficacy in reversing anticoagulation from vitamin K antagonists, however their usefulness with the new target specific oral anticoagulants is poorly understood. This article will review the properties of dabigatran, rivaroxaban and apixaban, as well as the limited literature available on the effectiveness of prothrombin complex concentrates in reversal of their anticoagulant effects. Additional studies are needed to more accurately define the role of prothrombin complex concentrates in patients with life threatening bleeding or who require emergent surgery, as current data is both limited and conflicting. PMID:24742134

  7. Reversibility of Apixaban Anticoagulation with a Four-Factor Prothrombin Complex Concentrate in Healthy Volunteers.

    PubMed

    Nagalla, S; Thomson, L; Oppong, Y; Bachman, B; Chervoneva, I; Kraft, W K

    2016-06-01

    It was hypothesized that the four-factor prothrombin complex concentrate (4F-PCC) Kcentra 25 unit/kg would reverse impairment of thrombin generation in healthy volunteers dosed with apixaban to steady state. In this randomized, two-period crossover, assessor-blinded trial, 12 healthy subjects received 5 mg apixaban every 12 h. Three h after the fifth dose, four-factor prothrombin complex concentrate (4F-PCC) 25 unit/kg or saline were infused. Serial blood samples were assessed for thrombin generation using PPP-reagent and PPP-reagent low, anti-Xa, PT, and PTT assays. Geometric mean ratio was calculated at 30 min postinfusion, and at 24, 48, and 72 h. Peak thrombin generation was 76% higher at 30 min postinfusion with 4F-PCC (p = 0.025). The difference declined to 24% at 24 h and resolved by 48 h. Other thrombin generation parameters were also partially normalized. There was no difference between 4F-PCC and saline in anti-Xa assessment at 30 min or later time points. © 2016 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

  8. Prothrombin Complex Concentrates in Pediatric Cardiac Surgery: The Current State and the Future.

    PubMed

    Ashikhmina, Elena; Said, Sameh; Smith, Mark M; Rodriguez, Vilmarie; Oliver, William C; Nuttall, Gregory A; Dearani, Joseph A; Schaff, Hartzell V

    2017-10-01

    After decades of practice of pediatric cardiac surgery, postoperative bleeding due to the immaturity of hemostasis, hemodilution, and hypothermia remains a concern. Recently, a new approach for adult coagulopathy after bypass has emerged. Prothrombin complex concentrates (PCCs), designed to treat bleeding in hemophilia patients, are safely and efficiently used off label for hemorrhage after bypass. However, optimal dosing, indications and contraindications, and laboratory tests to assess the efficacy of PCC use in children have not yet been established. This literature review outlines the challenges of bypass-related coagulopathy, the pharmacology, and the experience in use of PCCs, with a focus on their potential in pediatric cardiac surgery. After a thorough literature search of MEDLINE, Scopus, and Ovid databases using the term "prothrombin complex concentrate AND pediatric," 23 relevant articles were selected. The data supporting successful use of PCCs in acquired coagulopathy after cardiac surgery in adults have been increasing. Although small volume, low immunogenicity, efficiency, and speed in correcting coagulopathy are attractive qualities of PCCs for pediatric practice, current evidence is only anecdotal. The main concerns are unknown dosing regimens, the inability to closely monitor the effects of PCCs in real time, and a possibility of thrombotic complications, which can be particularly devastating in young congenital cardiac patients whose lives frequently depend upon the patency of artificial shunts. Extensive, high-quality research is warranted to fill in the gaps of knowledge regarding using PCCs in pediatric cardiac practice. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  9. On the use of prothrombin complex concentrate in patients with coagulopathy requiring tooth extraction.

    PubMed

    Morimoto, Yoshinari; Niwa, Hitoshi; Nakatani, Takeshi

    2010-12-01

    In patients on high-level anticoagulant therapy (prothrombin time-international normalized ratio [PT-INR] ≥ 4.5), surgical procedures can be carried out with bridging therapy using heparin. However, surgical treatment options are severely limited in patients on high-level anticoagulant therapy and who have heparin-induced thrombocytopenia (HIT), as heparin use is contraindicated. We performed tooth extraction using prothrombin complex concentrate (PCC) in 2 HIT patients on high-level anticoagulation therapy (PT-INR ≥ 4.5). Five hundred units of PCC were administered intravenously, and after 15 minutes, it was confirmed that PT-INR was less than 2.0. Tooth extraction was then performed and sufficient local hemostasis was achieved. At 3 hours after tooth extraction, PT-INR was 2.0 or higher and later increased to 4.0 or higher, but postoperative bleeding was mostly absent. When performing tooth extraction in HIT patients on high-level anticoagulant therapy, favorable hemostatic management was achieved through sufficient local hemostasis and transient warfarin reversal using PCC.

  10. More efficient reversal of dabigatran inhibition of coagulation by activated prothrombin complex concentrate or recombinant factor VIIa than by four-factor prothrombin complex concentrate.

    PubMed

    Lindahl, Tomas L; Wallstedt, Maria; Gustafsson, Kerstin M; Persson, Egon; Hillarp, Andreas

    2015-03-01

    The number of patients on antithrombotic treatment due to atrial fibrillation and venous thromboembolism is increasing fast due to an aging population. A growing proportion will be treated with novel oral anticoagulants, the first in clinical use was the direct oral thrombin inhibitor dabigatran (Pradaxa®). A small percentage of the patients on dabigatran will experience serious bleeding or be in need of urgent surgery. The aim of this study was to test the effects of different hemostatic agents in potentially reversing the anticoagulant effects in vitro in blood or platelet-rich plasma (PRP) spiked with dabigatran. Whole blood or PRP was spiked with the active substance dabigatran, 200 μg/L. We measured clotting time being induced by 1.4 pmol/L tissue factor using the instrument ReoRox2™ and initial clot growth velocity from a tissue factor covered surface using the instrument Thrombodynamics Analyzer T-2™. Dabigatran prolonged clotting time 5-fold but reduced clot growth velocity only slightly. The reversing effects of prothrombin complex concentrates (PCC), activated PCC (APCC) and recombinant activated factor VII (rFVIIa) were then tested. APCC (1.8 U/mL) reduced the prolonged clotting time by 1/3, rFVIIa (2 μg/L) only slightly (n = 10-20). The reduction was not significant using Mann-Whitney test but significant using t-test with Bonferronis' correction for multiple comparisons, whereas PCC (0.56 U/mL) had no effect on clotting time. APCC doubled initial clot growth velocity, although even more in the absence of dabigatran. In conclusion, APCC and rFVIIa, but not PCC, seem to reverse, at least partially, some effects of dabigatran on coagulation parameters. Systematic evaluation of case reports, registries and, ultimately, randomized clinical trials are needed to elucidate potential benefit for patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. [Safety and efficacy of a prothrombin complex concentrate in patients with coagulopathy and hemorrhage].

    PubMed

    Martínez-Calle, N; Marcos-Jubilar, M; Alfonso, A; Hernández, M; Hidalgo, F; Lecumberri, R; Páramo, Ja

    2014-01-01

    Prothrombin complex concentrates (PCC) are approved for urgent reversal of vitamin K antagonists (VKA). Recently, PCC have been used in the management of massive bleeding-associated coagulopathy. The present work evaluates safety and efficacy of PCC in a case series of both VKA reversal and massive bleeding. Retrospective review of cases treated with CCP (January 2010 to February 2013). Safety endpoints were infusion reactions and incidence of thromboembolic events. Efficacy endpoints were: 1) VKA reversal efficacy and 2) Massive bleeding coagulopathy reversal and 24h mortality. Thirty-one patients were included (22 male), median age 61 years (range 30-86). No infusion reactions were detected, and only 1 thrombotic episode was observed. VKA reversal was effective in 100% of patients (6/6), all of them with complete reversal of INR value. In massive bleeding, 24-hour survival was 64% (16/25). Invasive hemostatic procedures were required in 28% of patients (7/25). CCP use was correlated with bleeding control in 44% of cases (11/25), and also significantly associated with survival (p=0.01). CCP are safe and effective for the novel indication of adjuvant treatment in massive bleeding patients, as well as for traditional urgent reversal of VKA.

  12. Thromboembolic complications associated with the use of prothrombin complex and factor IX concentrates.

    PubMed

    Köhler, M; Hellstern, P; Lechler, E; Uberfuhr, P; Müller-Berghaus, G

    1998-09-01

    In 1994, shortly after a heat-treated prothrombin complex concentrate (PCC) had been withdrawn from the German market due to transmission of hepatitis B, the license of another brand was withdrawn, due to 3 acute fatalities associated with the use of this product. We report on the clinical data of altogether 5 patients, who died during a 3 month period in Germany after having received this brand of PCC. All patients had surgery, acquired deficiencies of coagulation factors, and underlying diseases predisposing for thrombosis or disseminated intravascular coagulation. PCC was administered for the prevention of bleeding. In three patients, a drug interaction of PCC with aprotinin may also have played a role. Several points, however, are suspicious of a major causative effect of the respective product, (a) the close temporal correlation between administration of the drug and the subsequent clinical as well as laboratory deterioration, (b) the accumulation of these adverse events in a short period of time, when the use and market share of this brand increased due to the shortage of other products, and (c) laboratory abnormalities of this brand which have been consistently observed in several in vitro studies.

  13. Activated Prothrombin Complex Concentrate versus Plasma for Reversal of Warfarin-Associated Hemorrhage.

    PubMed

    Rowe, Anthony Shaun; Mahbubani, Pinky S; Bucklin, Mason H; Clark, Christopher T; Hamilton, Leslie A

    2016-11-01

    To evaluate the efficacy and safety of an activated four-factor prothrombin complex concentrate (aPCC) versus plasma for the reversal of warfarin-associated hemorrhage. Single-center, retrospective cohort analysis of adult patients with warfarin-associated hemorrhage treated with either aPCC or plasma. Patients received either aPCC or plasma as treatment for warfarin-associated hemorrhage between January 1, 2011, and July 1, 2013. Patients with missing data points were excluded from the final analysis. Of the 276 patients included in the final analysis, 128 received aPCC and 148 received plasma. None. Those patients who received aPCC achieved a lower posttreatment INR (1.1 [0.1] vs 1.6 [0.5]; p<0.05). In addition, patients who received aPCC had a 4.3 times higher odds of achieving an INR of less than 1.4 (97 [75.8%] vs 65 [43.9%]; p<0.05; odds ratio [OR] = 4.3 [95% confidence interval (CI) 2.6-7.3]). When controlling for vitamin K administration, history of diabetes mellitus, receipt of the recommended reversal agent dose, and pretreatment INR, aPCC administration remained an independent predictor for achieving an international normalized ratio (INR) of less than 1.4 in the first 24 hours after treatment (OR = 3.75 [95% CI 2.11-6.65]; p<0.001). In addition, there was no statistical difference between the groups with regard to occurrences of infusion reaction, pulmonary embolism, deep vein thrombosis, stroke, or myocardial infarction. Compared with patients who received plasma, patients who received aPCC achieved a lower posttreatment INR, had a larger INR change, and were more likely to achieve an INR less than the prespecified goal. Those patients who received aPCC did not have a higher incidence of thromboembolic events. © 2016 Pharmacotherapy Publications, Inc.

  14. Bleeding in a Jehovah's Witness patient undergoing a redo aortic valve replacement controlled with cryoprecipitate and a prothrombin complex concentrate.

    PubMed

    Robblee, James A; Wilkes, Peter R H; Dickie, Sean J; Rubens, Fraser D; Bormanis, Janis

    2012-03-01

    This is a case report involving a middle-aged Jehovah's Witness patient who underwent a redo aortic valve replacement, coronary artery bypass graft, and Maze procedure facilitated by cardiopulmonary bypass. The consent process included a discussion of the management of bleeding and hemostasis in the perioperative period in the context of the patients' religious choice and the possible consequences of avoiding transfusion in massive bleeding. The medical team agreed to abide by the patient's wishes with respect to the blood and blood products deemed unacceptable by the patient irrespective of the consequences. The consent included a discussion of manufactured hemostatic agents that are designated by the Hospital Liaison Committee Network for Jehovah's Witnesses as subject to personal decision. There was also a discussion of recombinant agents available, all of which are acceptable to Jehovah's Witness patients. The patient accepted the use of cryoprecipitate, prothrombin complex concentrate, and recombinant factor VIIa. After separation from cardiopulmonary bypass and protamine administration, blood loss was 350 mL over a ten-minute period. The international normalized ratio (INR) was 3.5 at that time. Cryoprecipitate 15 U, 1-deamino-8-D-arginine vasopressin 16 U, and a prothrombin complex concentrate, Octaplex®, 60 mL were administered. Blood loss improved significantly. The INR in the cardiac surgical intensive care unit was 1.3. The sample was taken approximately one hour following the administration of the hemostatic agents. The patient's chest was closed, and chest tube drainage was 310 mL over the next 12 hr. This is a novel case involving the use of prothrombin complex concentrate in the setting of a Jehovah's Witness patient undergoing a complex operative procedure.

  15. Increasing concentrations of prothrombin complex concentrate induce disseminated intravascular coagulation in a pig model of coagulopathy with blunt liver injury.

    PubMed

    Grottke, Oliver; Braunschweig, Till; Spronk, Henri M H; Esch, Stephanie; Rieg, Annette D; van Oerle, Rene; ten Cate, Hugo; Fitzner, Christina; Tolba, Rene; Rossaint, Rolf

    2011-08-18

    Despite increasing use of prothrombin complex concentrate (PCC) to treat hemorrhage-associated coagulopathy, few studies have investigated PCC in trauma, and there is a particular lack of safety data. This study was performed to evaluate PCC therapy in a porcine model of coagulopathy with blunt liver injury. Coagulopathy was induced in 27 anesthetized pigs by replacing approximately 70% blood volume with hydroxyethyl starch 130/0.4 and Ringer's lactate solution; erythrocytes were collected and retransfused. Ten minutes after trauma, animals randomly received PCC (35 or 50 IU/kg) or saline. Coagulation parameters including thromboelastometry, thrombin generation, and blood loss were monitored for 2 hours. Internal organs were examined macroscopically and histologically to determine the presence of emboli and assess liver injury. Total blood loss was significantly lower and survival was higher in both PCC groups versus the control group (P < .05). These outcomes appeared to be dose-independent. Thromboembolism was found in all animals treated with 50 IU/kg PCC; 44% also showed signs of disseminated intravascular coagulation. Liver injury was similar in all animals. In conclusion, 35 IU/kg PCC safely improved coagulation and attenuated blood loss. However, the higher dose of PCC (50 IU/kg) appeared to increase the risk of thromboembolism and disseminated intravascular coagulation.

  16. Pharmacokinetics, thrombogenicity and safety of a double viral inactivated factor IX concentrate compared with a prothrombin complex concentrate.

    PubMed

    Ruiz-Sáez, A; Hong, A; Arguello, A; Echenagucia, M; Boadas, A; Fabbrizzi, F; Minichilli, F; Bosch, N B

    2005-11-01

    Therapeutic options for developing countries have to assure an optimum safety and efficacy and low-cost antihaemophilic concentrates. A single blind randomized crossover study was carried out in 12 previously treated HB patients, comparing the pharmacokinetics (PK), thrombogenicity (TG) and safety of two plasma-derived double-inactivated (solvent/detergent heating at 100 degrees C, 30 min) factor IX (FIX) concentrates, UMAN COMPLEX DI (product A) [plasma-derived prothrombin concentrates (PCC)] and a high purity FIX concentrate AIMAFIX DI (product B, HPFIX). In a non-bleeding state, they received one single intravenous dose 50 IU FIX kg(-1) of PCC or HPFIX, and after a wash-out period of 14 days, the other product. We evaluated acute tolerance and determined PK parameters based on FIX levels measured over a 50 h postinfusion period. We studied fibrinogen, platelets, antithrombin, F1 + 2, TAT, D-dimer, over a 360 min postinfusion period. Ten cases remained in on-demand treatment for 6 months, five with PCC and five with HPFIX. PK and anti-FIX inhibitors were repeated at 3 and 6 months. No inhibitors were detected. PK values (PCC vs. HPFIX): clearence (CL; mL h(-1) kg(-1)) 5.2 +/- 1.4 vs. 6.5 +/- 1.4; the volume of distribution at steady state (mL kg(-1)) 154.9 +/- 54.9 vs. 197.5 +/- 72.5; mean residence time (h) 29.7 +/- 8.1 vs. 30.7 +/- 9.2; T(1/2) (h) 22.3 +/- 7 vs. 23.5 +/- 12.3; incremental recovery (IR; U dL(-1) U(-1) kg(-1)) 0.96 +/- 0.17 vs. 0.76 +/- 0.13. HPFIX showed significant lower IR and higher CL. There were no differences in PK at 3 and 6 months. In TG, significant increments in TAT and F1 + 2 at 30 min and 6 h were found with PCC. Product B PK results agrees with reported results for other HPFIX preparations. Use of PCC product A has to consider its thrombogenic activity.

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

    PubMed

    Moe, Donald Michael; Lallemand, Michael Scott; McClellan, John Mason; Smith, Joshua Porter; Marko, Shannon T; Eckert, Matthew J; Martin, Matthew J

    2017-07-12

    Bleeding is a leading cause of preventable death following 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 (3PCC) versus 4-factor (4PCC) products. We aimed to assess and compare their safety and efficacy in a porcine model of severe hemorrhagic shock and coagulopathy. Twenty-five adult Yorkshire swine underwent 35% volume hemorrhage, ischemia-reperfusion injury, and protocolized crystalloid resuscitation. Seventeen animals were randomized at 4 hours following model creation to receive a 45-IU/kg dose of either 3PCC or 4PCC. An additional 8 animals received autologous plasma transfusion prior to 4PCC to better characterize response to PCC. Individual factor levels were drawn at 4 and 6 hours. The model created significant acidosis with mean pH 7.21 and lactate of 9.6 mmol/L. Following 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 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. 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

  18. An observational, prospective, two-cohort comparison of a fixed versus variable dosing strategy of prothrombin complex concentrate to counteract vitamin K antagonists in 240 bleeding emergencies.

    PubMed

    Khorsand, Nakisa; Veeger, Nic J G M; van Hest, Reinier M; Ypma, Paula F; Heidt, Jeroen; Meijer, Karina

    2012-10-01

    Despite years of experience with vitamin K antagonist-associated bleeding events, there is still no evidence to help identify the optimal treatment with prothrombin complex concentrates. Variable dosing and fixed dose strategies are being used. In this observational prospective two-cohort study, we aimed to assess the non-inferiority of a low fixed PCC dose (1,040 IU Factor IX) compared to the registered variable dosing regimen based on baseline International Normalized Rate, bodyweight, and target International Normalized Rate, to counteract vitamin K antagonists in a bleeding emergency in a daily clinical practice setting. Non-inferiority of the fixed prothrombin complex concentrate dose was hypothesized with a margin of 4%. Main end points were proportion of patients reaching the target International Normalized Rate (< 2.0) after prothrombin complex concentrate treatment, and successful clinical outcome. Target International Normalized Rate was reached in 92% of the fixed dose patients (n=101) versus 95% of variable dose patients (n=139) resulting in a risk difference of -2.99% (90% CI: - 8.6 to 2.7) (non-inferiority not confirmed). Clinical outcome was successful in 96% and 88% of fixed versus variable dose, respectively, with a risk difference of 8.3% (90% CI: 2.7-13.9; non-inferiority confirmed). Although a lower fixed prothrombin complex concentrate dose was associated with successful clinical outcome, fewer patients reached the target International Normalized Rate.

  19. Endogenous thrombin potential following hemostatic therapy with 4-factor prothrombin complex concentrate: a 7-day observational study of trauma patients

    PubMed Central

    2014-01-01

    Introduction Purified prothrombin complex concentrate (PCC) is increasingly used as hemostatic therapy for trauma-induced coagulopathy (TIC). However, the impact of PCC administration on coagulation status among patients with TIC has not been adequately investigated. Methods In this observational, descriptive study, data relating to thrombin generation were obtained from plasma samples gathered prospectively from trauma patients upon emergency room (ER) admission and over the following 7 days. Standard coagulation tests, including measurement of antithrombin (AT) and fibrinogen, were performed. Three groups were investigated: patients receiving no coagulation therapy (NCT group), patients receiving fibrinogen concentrate only (FC group), and patients treated with PCC and fibrinogen concentrate (FC-PCC group). Results The study population (77 patients) was predominantly male (84.4%); mean age was 40 ± 15 years and mean injury severity score was 25.6 ± 12.7. There were no significant differences between the three study groups in thrombin-related parameters upon ER admission. Endogenous thrombin potential (ETP) was significantly higher in the FC-PCC group compared with the NCT group on days 1 to 4 and the FC group on days 1 to 3. AT levels were significantly lower in the FC-PCC group from admission until day 3 (versus FC group) or day 4 (versus NCT group). Fibrinogen increased over time, with no significant between-group differences after ER admission. Despite ETP being higher, prothrombin time and activated partial thromboplastin time were significantly prolonged in the FC-PCC group from admission until day 3 to 4. Conclusions Treatment with PCC increased ETP for several days, and patients receiving PCC therapy had low AT concentrations. These findings imply a potential pro-thrombotic state not reflected by standard coagulation tests. This is probably important given the postoperative acute phase increase in fibrinogen levels, although studies with

  20. Prothrombin complex concentrate administration for bleeding associated with non-vitamin K antagonist oral anticoagulants: The SAMURAI-NVAF study.

    PubMed

    Yoshimura, Sohei; Sato, Shoichiro; Todo, Kenichi; Okada, Yasushi; Furui, Eisuke; Matsuki, Takayuki; Yamagami, Hiroshi; Koga, Masatoshi; Takahashi, Jun C; Nagatsuka, Kazuyuki; Arihiro, Shoji; Toyoda, Kazunori

    2017-04-15

    Antidotes appropriate for non-vitamin K antagonist (VKA) oral anticoagulants (NOACs) are not yet in widespread clinical use. Efficacy of prothrombin complex concentrate (PCC) in NOAC-associated bleeding remains unclarified. Ten NOAC users (4 women, median 74years old) who developed major bleeding and received PCC were prospectively enrolled. Eight single-center NOAC users (0 women, median 74years old) with intracerebral hemorrhage, who over the same period did not receive PCC, were studied for comparison. Of the 10 PCC-treated patients, 8 developed intracerebral hemorrhage, 1 developed subdural hematoma, and another developed gastrointestinal bleeding. The median size of intracerebral hemorrhage was 8mL, relatively lower than the reported size for patients without NOACs. Patients received a median of 1000IU or 16IU/kg of PCC. Before and 1h after PCC administration, the median PT-INR changed from 1.41 to 1.09 (p<0.05) and median aPTT changed from 35.4 to 38.0s (p=0.39). Five patients developed intracranial hematoma expansion and 4 required surgical hematoma evacuation. No symptomatic thrombotic events occurred in either group, no participants died, and 2 participants from each group were independent. Ten NOAC users developed major bleeding and were given relatively low doses of PCC. The effect of PCC on early cessation of bleeding was unclear, while the therapy did not trigger thromboembolic complications. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Assessing the Efficacy of Prothrombin Complex Concentrate in Multiply Injured Patients With High-Energy Pelvic and Extremity Fractures.

    PubMed

    Joseph, Bellal; Khalil, Mazhar; Harrison, Caitlyn; Swartz, Tianyi; Kulvatunyou, Narong; Haider, Ansab A; Jokar, Tahereh O; Burk, David; Mahmoud, Ali; Latifi, Rifat; Rhee, Peter

    2016-12-01

    Prothrombin complex concentrate (PCC) is being increasingly used for reversing induced coagulopathy of trauma. However, the use of PCC for reversing coagulopathy in multiply injured patients with pelvic and/or lower extremity fractures remains unclear. The aim of our study was to assess the efficacy of PCC for reversing coagulopathy in this group of patients. Two-year retrospective analysis. Our level I trauma center. All coagulopathic [International normalized ratio (INR) ≥1.5] trauma patients. Patients with femur, tibia, or pelvic fracture were included. Patients were divided into 2 groups: PCC (single dose) and fresh frozen plasma (FFP). Patients in the 2 groups were matched using propensity score matching. Time to correction of INR, time to intervention, development of thromboembolic complications, mortality, and cost of therapy. A total of 81 patients (PCC: 27, FFP: 54) were included. Patients who received PCC had faster correction of INR and shorter time to surgical intervention in comparison to patients who received FFP. PCC therapy was also associated with lower overall blood product requirement (P = 0.02) and lower transfusion costs (P = 0.0001). In a matched cohort of multiply injured patients with pelvic and/or lower extremity fractures, administration of a single dose of PCC significantly reduced the time to correction of INR and time to intervention compared with patients who received FFP therapy. This may allow orthopaedic surgeons to more safely proceed with early, definitive fixation strategies. Therapeutic level III. See Instructions for Authors for a complete description of levels of evidence.

  2. Efficacy of viral clearance methods used in the manufacture of activated prothrombin complex concentrates: focus on AUTOPLEX T.

    PubMed

    Horwith, G; Revie, D R

    1999-09-01

    Various methods are described for the elimination of infectious viruses from activated prothrombin complex concentrates (aPCCs) and for the analysis of the final products (AUTOPLEX T and FEIBA VH). Viruses of concern in human plasma-derived products are enveloped (hepatitis B and C, cytomegalovirus, Epstein-Barr virus, and human immunodeficiency virus [HIV]) and nonenveloped (hepatitis A and parvovirus B19). Donated blood used for AUTOPLEX T is screened for antihepatitis C, HBsAg, anti-HIV types 1 and 2, and p24 antigen. Plasma pools utilized for raw materials are also tested by PCR for HIV and hepatitis C virus. Partial virus inactivation and partitioning are achieved by purification of the aPCC. Further reduction of virus infectivity is accomplished by lyophilization and dry-heat treatment. Each step undergoes virus elimination validation studies in which a relevant sample is 'spiked' with the appropriate virus or model virus. The total reduction in virus from raw material to final product can then be calculated. For AUTOPLEX T the cumulative log10 reduction factors for several viruses vary from 4.2 to 14.3. This ensures an exceptionally high margin of safety. Definitive evidence for product safety was obtained by clinical observation of treated patients. The viral inactivation process of AUTOPLEX T involves a four-tier viral safety program, including Cohn alcohol fractionation and dry-heat treatment, in place of the two-stage vapour-heating process for FEIBA.

  3. Pathogen safety of a pasteurized four-factor human prothrombin complex concentrate preparation using serial 20N virus filtration.

    PubMed

    Nowak, Thomas; Popp, Birgit; Gröner, Albrecht; Schäfer, Wolfram; Kalina, Uwe; Enssle, Karlheinz; Roth, Nathan J

    2017-05-01

    Beriplex P/N/Kcentra/Coaplex/Confidex is a four-factor human prothrombin complex concentrate (PCC). Here, we describe the pathogen safety profile and biochemical characteristics of an improved manufacturing process that further enhances the virus safety of Beriplex P/N. Samples of product intermediates were spiked with test viruses, and prions were evaluated under routine production and robustness conditions of the scale-down version of the commercial manufacturing process for their capacity to inactivate or remove pathogens. The PCC was characterized by determining the activity of Factor (F)II, FVII, FIX, FX, protein C, and protein S and the concentration of heparin and antithrombin III in nine product lots. The manufacturing process had a very high virus reduction capacity for a broad variety of virus challenges (overall reduction factors ≥15.5 to ≥18.4 log for enveloped viruses and 11.5 to ≥11.9 log for nonenveloped viruses). The high virus clearance capacity was provided by two dedicated virus reduction steps (pasteurization and serial 20N virus filtration) that provided effective inactivation and removal of viruses and a purification step (ammonium sulfate precipitation and adsorption to calcium phosphate) that contributed to the overall virus removal capacity. The diethylaminoethyl (DEAE) chromatography and ammonium sulfate precipitation steps removed prions to below the limit of detection. The levels of different clotting factors in the final product were well balanced. The improved manufacturing process of Beriplex P/N further enhances the margin of pathogen safety based on its capacity to remove and inactivate a wide range of virus challenges. © 2017 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  4. Prothrombin Complex Concentrate

    PubMed Central

    Cada, Dennis J.; Levien, Terri L.; Baker, Danial E.

    2013-01-01

    Each month, subscribers to The Formulary Monograph Service receive 5 to 6 well-documented monographs on drugs that are newly released or are in late phase 3 trials. The monographs are targeted to Pharmacy & Therapeutics Committees. Subscribers also receive monthly 1-page summary monographs on agents that are useful for agendas and pharmacy/nursing in-services. A comprehensive target drug utilization evaluation/medication use evaluation (DUE/MUE) is also provided each month. With a subscription, the monographs are sent in print and are also available on-line. Monographs can be customized to meet the needs of a facility. A drug class review is now published monthly with The Formulary Monograph Service. Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. For more information about The Formulary Monograph Service, call The Formulary at 800-322-4349. The December 2013 monograph topics are vortioxetine, mechlorethamine gel, brimonidine tartrate topical gel, obinutuzumab, and miltefosine. The DUE/MUE is on vortioxetine. PMID:24474837

  5. Prothrombin complex concentrate accelerates international normalized ratio reversal and diminishes the extension of intracranial hemorrhage in geriatric trauma patients.

    PubMed

    Edavettal, Mathew; Rogers, Amelia; Rogers, Frederick; Horst, Michael; Leng, Wichitah

    2014-04-01

    Warfarin therapy increases the incidence intracranial hemorrhage (ICH), especially in the geriatric population. Timely reversal of international normalized ratio (INR) is integral in the management of these patients for whom fresh frozen plasma (FFP) with vitamin K is the standard of treatment. We hypothesized that implementing a protocol that used prothrombin complex concentrate (PCC) would reverse INR values more swiftly and decrease the amount of FFP administered. In November 2011, a protocol was implemented for administering PCC to the geriatric population on warfarin admitted for life-threatening bleeds. These patients received 25 IU/kg ideal body weight of a three-factor PCC (Profilnine SD) if their INR was over 1.5 or greater. FFP was given if follow-up INR revealed an INR of 1.5 or greater. Retrospectively the data from 29 patients who received PCC were compared with a historical control group of 34 patients. Protocol use resulted in a significantly faster INR reversal (PCC: 151.6 ± 84.3 minutes vs control: 485.0 ± 321 minutes; P < 0.001), time to achieve an INR less than 1.5 (PCC: 484 ± 242 minutes vs control: 971 ± 1208 minutes; P = 0.036), and less FFP administered (PCC: 1.3 ± 1.0 vs control:3.3 ± 1.5; P < 0.001). PCC patients had a decreased incidence of progression of their ICH (PCC: 17.2% vs control: 44.2%; P = 0.031). Rapid reversal of coagulopathy in geriatric patients on warfarin is vital to limit the extent of ICH. PCC allows a much more rapid reversal than standard treatment with only FFP and vitamin K. Adopting such a protocol is associated not only with a more rapid reversal and less FFP use, but also less patients went on to extend their head bleeds.

  6. Safety and efficacy of prothrombin complex concentrate as first-line treatment in bleeding after cardiac surgery.

    PubMed

    Cappabianca, Giangiuseppe; Mariscalco, Giovanni; Biancari, Fausto; Maselli, Daniele; Papesso, Francesca; Cottini, Marzia; Crosta, Sandro; Banescu, Simona; Ahmed, Aamer B; Beghi, Cesare

    2016-01-06

    Bleeding after cardiac surgery requiring surgical reexploration and blood component transfusion is associated with increased morbidity and mortality. Although prothrombin complex concentrate (PCC) has been used satisfactorily in bleeding disorders, studies on its efficacy and safety after cardiopulmonary bypass are limited. Between January 2005 and December 2013, 3454 consecutive cardiac surgery patients were included in an observational study aimed at investigating the efficacy and safety of PCC as first-line coagulopathy treatment as a replacement for fresh frozen plasma (FFP). Starting in January 2012, PCC was introduced as solely first-line treatment for bleeding following cardiac surgery. After one-to-one propensity score-matched analysis, 225 pairs of patients receiving PCC (median dose 1500 IU) and FFP (median dose 2 U) were included. The use of PCC was associated with significantly decreased 24-h post-operative blood loss (836 ± 1226 vs. 935 ± 583 ml, p < 0.0001). Propensity score-adjusted multivariate analysis showed that PCC was associated with significantly lower risk of red blood cell (RBC) transfusions (odds ratio [OR] 0.50; 95% confidence interval [CI] 0.31-0.80), decreased amount of RBC units (β unstandardised coefficient -1.42, 95% CI -2.06 to -0.77) and decreased risk of transfusion of more than 2 RBC units (OR 0.53, 95% CI 0.38-0.73). Patients receiving PCC had an increased risk of post-operative acute kidney injury (AKI) (OR 1.44, 95% CI 1.02-2.05) and renal replacement therapy (OR 3.35, 95% CI 1.13-9.90). Hospital mortality was unaffected by PCC (OR 1.51, 95% CI 0.84-2.72). In the cardiac surgery setting, the use of PCC compared with FFP was associated with decreased post-operative blood loss and RBC transfusion requirements. However, PCC administration may be associated with a higher risk of post-operative AKI.

  7. 328 A Propensity-Based Analysis of the Use of Prothrombin Complex Concentrate Prior to Emergent Neurosurgical Procedures.

    PubMed

    Agarwal, Prateek; Ramayya, Ashwin G; Abdullah, Kalil G; Nayak, Nikhil; Lucas, Timothy H

    2016-08-01

    Reversal of anticoagulation is required to mitigate the risk of intracranial bleeding before urgent neurosurgical procedures. New pharmacological agents, such as multifactor prothrombin complex concentrate (PCC; Kcentra), promise rapid efficacy but may raise the probability of thrombotic complications above vitamin K infusion or administration of fresh frozen plasma (FFP). In this study, we examined the rate of thrombotic complications in neurosurgical patients who received either PCC or FFP and Vitamin K before undergoing urgent surgery. Sixty-three consecutive patients who received anticoagulation reversal for urgent neurosurgical procedures were identified between 2008 and 2014 at a level I trauma center. They were divided into 2 cohorts based on reversal method, either PCC (n = 28) or FFP/Vitamin K (n = 35). The rate of thrombotic complications within 72 hours of reversal was compared using a 2-sample t test. To minimize selection bias, a multivariate propensity score-matching analysis was then used to identify a control group of FFP patients most similar to patients in the PCC group based on age, sex, trauma, altered mental status, and preexisting heart failure. Thrombotic complications were uncommon but not rare in this neurosurgical population, occurring in 8.3% of treated patients (3/63). There was no difference in thrombotic complication rate between groups, 7.14% (2/28; PCC group) vs 2.86% (1/28; FFP group; P = ns). Propensity matching analysis verified this finding after controlling for any selection bias. Thrombotic complications in neurosurgical patients requiring rapid reversal at a level I trauma center are uncommon but not rare. New pharmacological agents have similar rates of thrombotic complications as FFP. In this limited sample, use of PCC did not pose a significant increase in risk compared with FFP in the management of intracranial bleeding.

  8. A French multicenter randomised trial comparing two dose-regimens of prothrombin complex concentrates in urgent anticoagulation reversal

    PubMed Central

    2013-01-01

    Introduction Prothrombin complex concentrates (PCC) are haemostatic blood preparations indicated for urgent anticoagulation reversal, though the optimal dose for effective reversal is still under debate. The latest generation of PCCs include four coagulation factors, the so-called 4-factor PCC. The aim of this study was to compare the efficacy and safety of two doses, 25 and 40 IU/kg, of 4-factor PCC in vitamin K antagonist (VKA) associated intracranial haemorrhage. Methods We performed a phase III, prospective, randomised, open-label study including patients with objectively diagnosed VKA-associated intracranial haemorrhage between November 2008 and April 2011 in 22 centres in France. Patients were randomised to receive 25 or 40 IU/kg of 4-factor PCC. The primary endpoint was the international normalised ratio (INR) 10 minutes after the end of 4-factor PCC infusion. Secondary endpoints were changes in coagulation factors, global clinical outcomes and incidence of adverse events (AEs). Results A total of 59 patients were randomised: 29 in the 25 IU/kg and 30 in the 40 IU/kg group. Baseline demographics and clinical characteristics were comparable between the groups. The mean INR was significantly reduced to 1.2 - and ≤1.5 in all patients of both groups - 10 minutes after 4-factor PCC infusion. The INR in the 40 IU/kg group was significantly lower than in the 25 IU/kg group 10 minutes (P = 0.001), 1 hour (P = 0.001) and 3 hours (P = 0.02) after infusion. The 40 IU/kg dose was also effective in replacing coagulation factors such as PT (P = 0.038), FII (P = 0.001), FX (P <0.001), protein C (P = 0.002) and protein S (0.043), 10 minutes after infusion. However, no differences were found in haematoma volume or global clinical outcomes between the groups. Incidence of death and thrombotic events was similar between the groups. Conclusions Rapid infusion of both doses of 4-factor PCC achieved an INR of 1.5 or less in all patients with a lower INR observed in the 40 IU

  9. Goal-directed coagulation management of major trauma patients using thromboelastometry (ROTEM®)-guided administration of fibrinogen concentrate and prothrombin complex concentrate

    PubMed Central

    2010-01-01

    Introduction The appropriate strategy for trauma-induced coagulopathy management is under debate. We report the treatment of major trauma using mainly coagulation factor concentrates. Methods This retrospective analysis included trauma patients who received ≥ 5 units of red blood cell concentrate within 24 hours. Coagulation management was guided by thromboelastometry (ROTEM®). Fibrinogen concentrate was given as first-line haemostatic therapy when maximum clot firmness (MCF) measured by FibTEM (fibrin-based test) was <10 mm. Prothrombin complex concentrate (PCC) was given in case of recent coumarin intake or clotting time measured by extrinsic activation test (EXTEM) >1.5 times normal. Lack of improvement in EXTEM MCF after fibrinogen concentrate administration was an indication for platelet concentrate. The observed mortality was compared with the mortality predicted by the trauma injury severity score (TRISS) and by the revised injury severity classification (RISC) score. Results Of 131 patients included, 128 received fibrinogen concentrate as first-line therapy, 98 additionally received PCC, while 3 patients with recent coumarin intake received only PCC. Twelve patients received FFP and 29 received platelet concentrate. The observed mortality was 24.4%, lower than the TRISS mortality of 33.7% (P = 0.032) and the RISC mortality of 28.7% (P > 0.05). After excluding 17 patients with traumatic brain injury, the difference in mortality was 14% observed versus 27.8% predicted by TRISS (P = 0.0018) and 24.3% predicted by RISC (P = 0.014). Conclusions ROTEM®-guided haemostatic therapy, with fibrinogen concentrate as first-line haemostatic therapy and additional PCC, was goal-directed and fast. A favourable survival rate was observed. Prospective, randomized trials to investigate this therapeutic alternative further appear warranted. PMID:20374650

  10. Global coagulation tests: their applicability for measuring direct factor Xa- and thrombin inhibition and reversal of anticoagulation by prothrombin complex concentrate.

    PubMed

    Dinkelaar, Jasper; Patiwael, Sanne; Harenberg, Job; Leyte, Anja; Brinkman, Herm Jan M

    2014-11-01

    Specific mass spectrometry and direct activated factor X (Xa)- and thrombin inhibition assays do not allow determination of the reversal of anticoagulant effects of non-vitamin K direct oral anticoagulants (NOACs) by prothrombin complex concentrate (PCC). The objective of this study was the evaluation of the applicability of a variety of commercially available global coagulation assays in analyzing the reversal of NOAC anticoagulation by PCC. Plasma and whole blood were spiked with apixaban or dabigatran and PCC was added to these samples. Prothrombin time (PT), modified PT (mPT), activated partial prothrombin time (APTT), thrombography (CAT method) and thromboelastography (ROTEM, TEG) were performed. Assays triggered by contact activation (APTT, INTEM) did not show inhibitor reversal by PCC. Assays triggered by tissue factor (TF) showed NOAC type and NOAC concentration dependent anticoagulation reversal effects of PCC ranging from partial normalization to overcorrection of the following parameters: clotting or reaction time (PT, mPT TEG-TF, EXTEM, FIBTEM); angle in thromboelastography (TEG-TF); thrombin generation (CAT) lag time, endogenous thrombin potential (ETP) and peak thrombin. Extent of reversal was assay reagent dependent. ETP (5 pM TF) was the only parameter showing complete reversal of anticoagulation by PCC for all NOACs ranging from 200 to 800 μg/L. ETP fits with the concept that reversal assessment of NOAC anticoagulation by PCC should be based on measurements on the clotting potential or thrombin generating potential of the plasma or whole blood patient sample. Low sensitivity of ETP for NOACs and its correlation with bleeding are issues that remain to be resolved.

  11. Effectiveness of prothrombin complex concentrate (PCC) in neonates and infants with bleeding or risk of bleeding: a systematic review and meta-analysis.

    PubMed

    Zeng, Linan; Choonara, Imti; Zhang, Lingli; Li, Youping; Shi, Jing

    2017-05-01

    To systematically evaluate the effectiveness of prothrombin complex concentrate (PCC) in neonates and infants, we performed a systematic review and meta-analysis based on current evidence. Quality of studies was assessed by Cochrane Collaboration's risk of bias tool and Newcastle-Ottawa quality assessment scale. For dichotomous data, we obtained the number of events and total number and calculated the relative risk (RR) with 95% confidence intervals (CI). For continuous variables, we obtained mean and standard deviation (SD) values and calculated mean difference (MD) with 95% CI. We identified six trials and two cohort studies. For trials, selection bias and performance bias were high, while detection bias, attrition bias, and reporting bias were relatively low. For cohort studies, selection bias was low. Both individual studies and meta-analysis failed to find any benefit of PCC on mortality. Meta-analysis also failed to show any benefit in reducing intracranial hemorrhage. The effectiveness of PCC on the correction of hemostatic defects was inconsistent among studies. In addition, PCC was not more effective than fresh frozen plasma (FFP) in correcting hemostatic defects. There is insufficient evidence to allow a recommendation for use of PCC in neonates and infants. What is Known: • Prothrombin Complex Concentrate is becoming increasingly used off-label for treatment of neonates and infants with severe bleeding or risk of severe bleeding. • Some case reports showed PCC seemed to be effective for infants and children with coagulation factor deficiency, but evidence about the effectiveness of PCC to reverse serious Vitamin K Deficiency Bleeding is limited. What is New: • As far as we know, this is the first systematic review that evaluates the effectiveness of PPC in neonates with bleeding or risk of bleeding. • There is insufficient evidence to allow a recommendation for use of PCCs in neonates and infants.

  12. Management of Bleeding in Post-liver Disease, Surgery and Biopsy in Patients With High Uncorrected International Normalized Ratio With Prothrombin Complex Concentrate: An Iranian Experience.

    PubMed

    Parand, Alireza; Honar, Naser; Aflaki, Khashayar; Imanieh, Mohammad Hadi; Haghighat, Mahmood; Cohan, Nader; Haghpanah, Sezaneh; Marietta, Marco; Serati, Zahra; Haghbin, Saeedeh; Karimi, Mehran

    2013-12-01

    To evaluate the efficacy of prothrombin complex concentrate (PCC) in the management of bleeding in patients with liver disease and patients undergoing surgery or biopsy who had a high uncorrected international normalized ratio (INR). In this study, we examined an Iranian sample and investigated the efficacy of PCC to manage bleeding in patients with liver disease and also patients with high uncorrected INR who were scheduled for surgery or biopsy. A total of 25 patients including 16 patients with post-liver disease bleeding (group 1) and 9 patients with high uncorrected INR who were scheduled for surgery or biopsy (group 2) were enrolled. All patients were treated with 25 IU/kg PCC, and efficacy was defined as any reduction in or cessation of bleeding episodes and correction of INR before surgery or biopsy. The patients were also evaluated for any adverse effects. INR decreased significantly in both groups of patients, with no bleeding episodes during or after the study in group 1 and during or after surgery/biopsy in group 2. All patients tolerated the therapy well without any significant adverse effects. The efficacy of PCC therapy was satisfactory in this study. PCC therapy in patients with liver disease and patients undergoing surgery or biopsy seems to be effective and safe, and may be a good treatment strategy for these patients, if fresh frozen plasma or vitamin K are not effective.

  13. Increased risk of volume overload with plasma compared with four‐factor prothrombin complex concentrate for urgent vitamin K antagonist reversal

    PubMed Central

    Refaai, Majed A.; Goldstein, Joshua N.; Lee, Martin L.; Durn, Billie L.; Milling, Truman J.; Sarode, Ravi

    2015-01-01

    BACKGROUND Plasma is commonly used for vitamin K antagonist (VKA) reversal, but observational studies suggest that it is associated with transfusion‐related adverse reactions (e.g., volume overload). However, this issue has not previously been addressed in a randomized controlled trial (RCT). STUDY DESIGN AND METHODS Factors associated with volume overload were examined using data from two Phase IIIb RCTs comparing plasma with four‐factor prothrombin complex concentrate (4F‐PCC, Beriplex/Kcentra, CSL Behring) for urgent VKA reversal. VKA‐treated patients with major bleeding (NCT00708435) or requiring an urgent surgical or invasive procedure (NCT00803101) were randomly assigned (1:1) to receive either plasma or 4F‐PCC, concomitant with vitamin K. Adverse events (AEs) and serious AEs were prospectively captured up to Day 10 and 45, respectively. Volume overload predictors were evaluated on a univariate and multivariate basis. RESULTS A total of 388 patients (4F‐PCC, n = 191; plasma, n = 197) were enrolled. Volume overload occurred in 34 (9%) patients (4F‐PCC, n = 9; plasma, n = 25). In univariate analyses, use of plasma (vs. 4F‐PCC), use of nonstudy plasma and/or platelets, race, history of congestive heart failure (CHF), and history of renal disease were associated with volume overload. In multivariate analyses, use of plasma (vs. 4F‐PCC), history of CHF, and history of renal disease were independent volume overload predictors. In an additional analysis restricted to volume overload events recorded up to Day 7, only use of plasma (vs. 4F‐PCC) was an independent volume overload predictor. CONCLUSIONS After adjusting for other potential risk factors, plasma use was independently associated with a greater risk of volume overload than 4F‐PCC in patients requiring urgent VKA reversal. PMID:26135740

  14. Guideline-concordant administration of prothrombin complex concentrate and vitamin K is associated with decreased mortality in patients with severe bleeding under vitamin K antagonist treatment (EPAHK study)

    PubMed Central

    2014-01-01

    Introduction In vitamin K antagonist (VKA)-treated patients with severe hemorrhage, guidelines recommend prompt VKA reversal with prothrombin complex concentrate (PCC) and vitamin K. The aim of this observational cohort study was to evaluate the impact of guideline concordant administration of PCC and vitamin K on seven-day mortality. Methods Data from consecutive patients treated with PCC were prospectively collected in 44 emergency departments. Type of hemorrhage, coagulation parameters, type of treatment and seven-day mortality mortality were recorded. Guideline-concordant administration of PCC and vitamin K (GC-PCC-K) were defined by at least 20 IU/kg factor IX equivalent PCC and at least 5 mg of vitamin K performed within a predefined time frame of eight hours after admission. Multivariate analysis was used to assess the effect of appropriate reversal on seven-day mortality in all patients and in those with intracranial hemorrhage (ICH). Results Data from 822 VKA-treated patients with severe hemorrhage were collected over 14 months. Bleeding was gastrointestinal (32%), intracranial (32%), muscular (13%), and “other” (23%). In the whole cohort, seven-day mortality was 13% and 33% in patients with ICH. GC-PCC-K was performed in 38% of all patients and 44% of ICH patients. Multivariate analysis showed a two-fold decrease in seven-day mortality in patients with GC-PCC-K (odds ratio (OR) = 2.15 (1.20 to 3.88); P = 0.011); this mortality reduction was also observed when only ICH was considered (OR = 3.23 (1.53 to 6.79); P = 0.002). Conclusions Guideline-concordant VKA reversal with PCC and vitamin K within eight hours after admission was associated with a significant decrease in seven-day mortality. PMID:24762166

  15. 3-Factor Versus 4-Factor Prothrombin Complex Concentrate for Warfarin Reversal in Severe Bleeding: A Multicenter, Retrospective, Propensity-Matched Pilot Study.

    PubMed

    Jones, G Morgan; Erdman, Michael J; Smetana, Keaton S; Mohrien, Kerry M; Vandigo, Joseph E; Elijovich, Lucas

    2016-07-01

    Current guidelines recommend 4-factor prothrombin complex concentrate (4PCC) for emergent reversal of bleeding secondary to warfarin. While current research has demonstrated superiority of 4PCC over plasma, direct comparisons with 3-factor PCC (3PCC) are lacking. The purpose of this study is to compare the efficacy and safety of 3PCC and 4PCC. We conducted a retrospective analysis of patients who received PCC at one of four medical centers. All patients in the 3PCC group were treated at one center that utilizes a fixed, weight-based dosing protocol. After evaluation of all patients meeting inclusion criteria, propensity-score matching was used to adjust for differences in treatment characteristics. There was no difference in the primary outcome of INR ≤ 1.4 between 3PCC and 4PCC in both the unmatched (85.7 vs. 90.6 %; p = 0.37) and matched (84.2 vs. 92.1 %; p = 0.48) analyses. There was a significant difference in goal INR achieved favoring 4PCC (56.3 vs 90.0 %; p < 0.02) when baseline INR > 4.0. A total of three thrombotic events were documented, all in the 4PCC group. We found no difference in the rate of INR reversal in those treated with 3PCC and 4PCC. However, those with a baseline INR > 4.0 may experience more successful INR reversal with 4PCC.

  16. Cost-Effectiveness Analysis of Biogeneric Recombinant Activated Factor VII (AryoSeven™) and Activated Prothrombin Complex Concentrates (FEIBA™) to Treat Hemophilia A Patients with Inhibitors in Iran

    PubMed Central

    Golestani, Mina; Eshghi, Peyman; Rasekh, Hamid Reza; Cheraghali, Abdoll Majid; Salamzadeh, Jamshid; Naderi, Majid; Managhchi, Mohammad Reza; Hoorfar, Hamid; Toogeh, Gholam Reza; Imani, Ali; Khodayari, Mohammad Taghi; Habibpanah, Behnaz; Hantooshzadeh, Razieh

    2016-01-01

    Nowadays, bypassing agents such as recombinant activated factor VII (rFVIIa) and activated prothrombin complex concentrates (aPCC) are used to treat bleeding episodes in the Hemophilia patients with inhibitors. AryoSeven® is an Iranian biogeneric rFVIIa with homogeneity of efficacy and the nature to NovoSeven in a comparative trial. The current clinical trial aimed to evaluate the cost-effectiveness of FEIBA and AryoSeven® by Decision Analytic Model according to the Iranian healthcare system. An open label, multi-center, cross-over clinical trial was designed. Patients were categorized into 3 groups based on their prior tendency to one or none of the products. To determine the premium therapeutic strategy, the Incremental cost-effectiveness ratio (ICER) was calculated. Protocol F led to more treatment success in group F than the other groups (P= 0.03). Also, there was a significant statistical difference between the mean of effectiveness scores in the groups using protocol F (P = 0.01). The effectiveness of protocol F and A were 89% and 72%, respectively. ICER cost US$ to manage an episode of bleeding to get one more unit of effectiveness using FEIBA VS. AryoSeven. Although the results showed that AryoSeven was more cost-effective compared to FEIBA, the two strategies were undominated. In other words, both medicines can be applied in the first line of the treatment if the cost of FEIBA was reduced. The present clinical trial was registered at IRCT website, under ID No.2013020612380N1. PMID:27642341

  17. Cost-Effectiveness Analysis of Biogeneric Recombinant Activated Factor VII (AryoSeven™) and Activated Prothrombin Complex Concentrates (FEIBA™) to Treat Hemophilia A Patients with Inhibitors in Iran.

    PubMed

    Golestani, Mina; Eshghi, Peyman; Rasekh, Hamid Reza; Cheraghali, Abdoll Majid; Salamzadeh, Jamshid; Naderi, Majid; Managhchi, Mohammad Reza; Hoorfar, Hamid; Toogeh, Gholam Reza; Imani, Ali; Khodayari, Mohammad Taghi; Habibpanah, Behnaz; Hantooshzadeh, Razieh

    2016-01-01

    Nowadays, bypassing agents such as recombinant activated factor VII (rFVIIa) and activated prothrombin complex concentrates (aPCC) are used to treat bleeding episodes in the Hemophilia patients with inhibitors. AryoSeven® is an Iranian biogeneric rFVIIa with homogeneity of efficacy and the nature to NovoSeven in a comparative trial. The current clinical trial aimed to evaluate the cost-effectiveness of FEIBA and AryoSeven® by Decision Analytic Model according to the Iranian healthcare system. An open label, multi-center, cross-over clinical trial was designed. Patients were categorized into 3 groups based on their prior tendency to one or none of the products. To determine the premium therapeutic strategy, the Incremental cost-effectiveness ratio (ICER) was calculated. Protocol F led to more treatment success in group F than the other groups (P= 0.03). Also, there was a significant statistical difference between the mean of effectiveness scores in the groups using protocol F (P = 0.01). The effectiveness of protocol F and A were 89% and 72%, respectively. ICER cost US$ to manage an episode of bleeding to get one more unit of effectiveness using FEIBA VS. AryoSeven. Although the results showed that AryoSeven was more cost-effective compared to FEIBA, the two strategies were undominated. In other words, both medicines can be applied in the first line of the treatment if the cost of FEIBA was reduced. The present clinical trial was registered at IRCT website, under ID No.2013020612380N1.

  18. Thromboembolic Events After Vitamin K Antagonist Reversal With 4-Factor Prothrombin Complex Concentrate: Exploratory Analyses of Two Randomized, Plasma-Controlled Studies.

    PubMed

    Milling, Truman J; Refaai, Majed A; Goldstein, Joshua N; Schneider, Astrid; Omert, Laurel; Harman, Amy; Lee, Martin L; Sarode, Ravi

    2016-01-01

    We evaluated thromboembolic events after vitamin K antagonist reversal in post hoc analyses of pooled data from 2 randomized trials comparing 4-factor prothrombin complex concentrate (4F-PCC) (Beriplex/Kcentra) with plasma. Unblinded investigators identified thromboembolic events, using standardized terms (such as "myocardial infarction," "deep vein thrombosis," "pulmonary embolism," and "ischemic stroke"). A blinded safety adjudication board reviewed serious thromboembolic events, as well as those referred by an independent unblinded data and safety monitoring board. We descriptively compared thromboembolic event and patient characteristics between treatment groups and included detailed patient-level outcome descriptions. We did not power the trials to assess safety. We enrolled 388 patients (4F-PCC: n=191; plasma: n=197) in the trials. Thromboembolic events occurred in 14 of 191 patients (7.3%) in the 4F-PCC group and 14 of 197 (7.1%) in the plasma group (risk difference 0.2%; 95% confidence interval -5.5% to 6.0%). Investigators reported serious thromboembolic events in 16 patients (4F-PCC: n=8; plasma: n=8); the data and safety monitoring board referred 2 additional myocardial ischemia events (plasma group) to the safety adjudication board for review. The safety adjudication board judged serious thromboembolic events in 10 patients (4F-PCC: n=4; plasma: n=6) as possibly treatment related. There were 8 vascular thromboembolic events in the 4F-PCC group versus 4 in the plasma group, and 1 versus 6 cardiac events, respectively. Among patients with thromboembolic events, 3 deaths occurred in each treatment group. All-cause mortality for the pooled population was 13 per group. We observed no relationship between thromboembolic event occurrence and factor levels transiently above the upper limit of normal; there were no notable differences in median factor or proteins C and S levels up to 24 hours postinfusion start in patients with and without thromboembolic events

  19. Safety of a Four-factor Prothrombin Complex Concentrate Versus Plasma for Vitamin K Antagonist Reversal: An Integrated Analysis of Two Phase IIIb Clinical Trials.

    PubMed

    Milling, Truman J; Refaai, Majed A; Sarode, Ravi; Lewis, Brandon; Mangione, Antoinette; Durn, Billie L; Harman, Amy; Lee, Martin L; Goldstein, Joshua N

    2016-04-01

    Clinicians often need to rapidly reverse vitamin K antagonists (VKAs) in the setting of major hemorrhage or urgent need for surgery. Little is known about the safety profile of the traditional reversal agent, plasma, or the newly approved agent, four-factor prothrombin complex concentrate (4F-PCC), in a randomized setting. This is an integrated analysis of safety data from two clinical trials that evaluated 4F-PCC versus plasma for the treatment of patients requiring rapid VKA reversal for acute major bleeding or prior to an urgent surgical/invasive procedure. This descriptive analysis comprised adverse event (AE) data from two phase IIIb, randomized, controlled trials. The bleeding and surgical studies were performed across 36 and 33 sites, respectively, in nine countries, with the integrated analysis comprising 388 patients (4F-PCC, n = 191; plasma, n = 197) aged ≥ 18 years, who required VKA reversal due to major bleeding or prior to an urgent surgical/invasive procedure. Patients received either 4F-PCC, containing nonactivated factors II, VII, IX, and X and proteins C and S (Beriplex/Kcentra, CSL Behring) or plasma, both dosed according to baseline international normalized ratio and body weight. Patients were also to receive vitamin K1. AEs and serious AEs (SAEs) were assessed up to days 10 and 45, respectively. The proportion of patients with AEs (4F-PCC, 115/191 [60.2%]; plasma, 124/197 [62.9%]) and SAEs (4F-PCC, 54/191 [28.3%]; plasma, 49/197 [24.9%]) was similar between groups. The proportion of patients with thromboembolic events was also similar between groups (4F-PCC, 14/191 [7.3%]; plasma, 14/197 [7.1%]). There were 13 (6.8%) deaths in the 4F-PCC group and 13 (6.6%) in the plasma group. Fluid overload events occurred in more patients in the plasma group than the 4F-PCC group (25 [12.7%] and 9 [4.7%], respectively). These safety data represent the largest controlled assessment of a 4F-PCC to date. For patients requiring urgent VKA reversal, 4F-PCC had a

  20. Cost analysis of prophylaxis with activated prothrombin complex concentrate vs. on-demand therapy with activated factor VII in severe haemophilia A patients with inhibitors, in Spain.

    PubMed

    Villarrubia, R; Oyagüez, I; Álvarez-Román, M T; Mingot-Castellano, M E; Parra, R; Casado, M A

    2015-05-01

    A cost analysis model was developed to compare annual cost of prophylaxis with activated prothrombin complex concentrate (aPCC) vs. on-demand therapy with activated recombinant factor VII (rFVIIa) in severe haemophilia A patients with inhibitors for the Spanish National Health System (NHS). Model inputs were drug cost for prophylaxis (aPCC) and for on-demand treatment (rFVIIa or aPCC); bleeding episodes management (excluding bypassing agent cost); surgical costs and disease management (excluding bleeding episodes). Annual bleeding episodes treated on-demand was assumed to be 25, whereas breakthrough bleeds on prophylaxis was 8. Dose for prophylaxis was 75.72 U kg(-1) , three times per week. The total on-demand dose/bleeding episode was 679.66 μg kg(-1) (rFVIIa) and 235.28 U kg(-1) (aPCC). The average bleeding cost (€2998) considered different bleeding sites (62.5% joints, 28.6% muscles and soft tissues, 3.6% mucocutaneous tissues and 5.4% other areas). A 7.5% deduction was applied to ex-factory drug prices. Unitary costs (€2013) derived from local databases. Sensitivity analyses (SA) were performed. Annual cost of aPCC prophylaxis (€524,358) was 16% lower than on-demand treatment with rFVIIa (€627,876). Yearly drug costs were €497,017 for aPCC (€73,166 for on-demand treatment and €423,850 for prophylaxis), and €548,870 for rFVIIa. Disease management cost (€2645 per year) and surgical procedures (€708 per year) were common for both strategies. In the SA prophylactic treatment led to savings between €26,225 and €-1,008,960. Prophylaxis with aPCC reduces number of bleeding episodes in severe haemophilia A patients with inhibitors. aPCC prophylaxis resulted in savings in excess of €100,000 per-patient per year, being 16% less costly than on-demand treatment with rFVIIa, for the Spanish NHS. © 2015 John Wiley & Sons Ltd.

  1. Reversal of anticoagulation with four-factor prothrombin complex concentrate without concurrent vitamin K (phytonadione) for urgent surgery in a patient at moderate-to-high risk for thromboembolism.

    PubMed

    Farley, Thomas Michael; Andreas, Elisha M

    2016-10-27

    Successful vitamin K antagonist (eg, warfarin) reversal with 4-factor prothrombin complex concentrate (4F-PCC) without vitamin K (phytonadione) for emergent surgery in a patient at moderate-to-high risk for thromboembolism is reported. This approach may decrease the risk for development of thrombus, as it limits the amount of time the patient's anticoagulation is subtherapeutic. It also may increase the risk of bleeding, so patient selection is essential if this strategy is employed. Caution must be exercised to complete the procedure or surgery in the window of peak 4F-PCC effect (∼1-6 hours postinfusion).

  2. Lupus anticoagulants form immune complexes with prothrombin and phospholipid that can augment thrombin production in flow.

    PubMed

    Field, S L; Hogg, P J; Daly, E B; Dai, Y P; Murray, B; Owens, D; Chesterman, C N

    1999-11-15

    Lupus anticoagulants (LA) are a family of autoantibodies that are associated with in vitro anticoagulant activity but a strong predisposition to in vivo thrombosis. They are directed against plasma phospholipid binding proteins, including prothrombin. We found that a murine monoclonal antiprothrombin antibody and 7 of 7 LA IgGs tested enhanced binding of prothrombin to 25:75 phosphatidyl serine:phosphatidyl choline vesicles in a concentration-dependent manner. We hypothesized that enhanced binding of prothrombin to phospholipid in the presence of LA IgG might result in increased thrombin production when reactions are performed in flow. Thrombin production by purified prothrombinase components was measured in a phospholipid-coated flow reactor. The flow reactor was incubated with prothrombin, calcium ions, and the IgGs and then perfused with prothrombin, calcium ions, the IgGs, factor Va, and factor Xa. A murine monoclonal antiprothrombin antibody and 4 of 6 LA IgGs from patients with a history of thrombosis increased thrombin production up to 100% over control in the first 15 minutes. In summary, LA IgGs concentrate prothrombin on a phospholipid surface that can augment thrombin production by prothrombinase in flow. These observations suggest that LA might propagate coagulation in flowing blood by facilitating prothrombin interaction with the damaged blood vessel wall.

  3. Reversal of Vitamin K Antagonist (VKA) effect in patients with severe bleeding: a French multicenter observational study (Optiplex) assessing the use of Prothrombin Complex Concentrate (PCC) in current clinical practice

    PubMed Central

    2012-01-01

    Introduction Prothrombin Complex Concentrate (PCC) is a key treatment in the management of bleeding related to Vitamin K antagonists (VKA). This study aimed to evaluate prospectively PCC use in patients with VKA-related bleeding in view of the French guidelines published in 2008. Methods All consecutive patients with VKA-related bleeding treated with a 4-factor PCC (Octaplex®) were selected in 33 French hospitals. Collected data included demographics, site and severity of bleeding, modalities of PCC administration, International Normalized Ratio (INR) values before and after PCC administration, outcomes and survival rate 15 days after infusion. Results Of 825 patients who received PCC between August 2008 and December 2010, 646 had severe bleeding. The main haemorrhage sites were intracranial (43.7%) and abdominal (24.3%). Mean INR before PCC was 4.4 ± 1.9; INR was unavailable in 12.5% of patients. The proportions of patients who received a PCC dose according to guidelines were 15.8% in patients with initial INR 2-2.5, 41.5% in patients with INR 2.5-3, 40.8% in patients with INR 3-3.5, 26.9% in patients with INR > 3.5, and 63.5% of patients with unknown INR. Vitamin K was administered in 84.7% of patients. The infused dose of PCC did not vary with initial INR; the mean dose was 25.3 ± 9.8 IU/Kg. Rates of controlled bleeding and target INR achievement were similar, regardless of whether or not patients were receiving PCC doses as per the guidelines. No differences in INR after PCC treatment were observed, regardless of whether or not vitamin K was administered. INR was first monitored after a mean time frame of 4.5 ± 5.6 hours post PCC. The overall survival rate at 15 days after PCC infusion was 75.4% (65.1% in patients with intracranial haemorrhage). A better prognosis was observed in patients reaching the target INR. Conclusions Severe bleeding related to VKA needs to be better managed, particularly regarding the PCC infused dose, INR monitoring and

  4. Four-factor prothrombin complex concentrate versus plasma for rapid vitamin K antagonist reversal in patients needing urgent surgical or invasive interventions: a phase 3b, open-label, non-inferiority, randomised trial.

    PubMed

    Goldstein, Joshua N; Refaai, Majed A; Milling, Truman J; Lewis, Brandon; Goldberg-Alberts, Robert; Hug, Bruce A; Sarode, Ravi

    2015-05-23

    Rapid reversal of vitamin K antagonist (VKA)-induced anticoagulation is often necessary for patients needing urgent surgical or invasive procedures. The optimum means of VKA reversal has not been established in comparative clinical trials. We compared the efficacy and safety of four-factor prothrombin complex concentrate (4F-PCC) with that of plasma in VKA-treated patients needing urgent surgical or invasive procedures. In a multicentre, open-label, phase 3b randomised trial we enrolled patients aged 18 years or older needing rapid VKA reversal before an urgent surgical or invasive procedure. We randomly assigned patients in a 1:1 ratio to receive vitamin K concomitant with a single dose of either 4F-PCC (Beriplex/Kcentra/Confidex; CSL Behring, Marburg, Germany) or plasma, with dosing based on international normalised ratio (INR) and weight. The primary endpoint was effective haemostasis, and the co-primary endpoint was rapid INR reduction (≤1·3 at 0·5 h after infusion end). The analyses were intended to evaluate, in a hierarchical fashion, first non-inferiority (lower limit 95% CI greater than -10% for group difference) for both endpoints, then superiority (lower limit 95% CI >0%) if non-inferiority was achieved. Adverse events and serious adverse events were reported to days 10 and 45, respectively. This trial is registered at ClinicalTrials.gov, number NCT00803101. 181 patients were randomised (4F-PCC n=90; plasma n=91). The intention-to-treat efficacy population comprised 168 patients (4F-PCC, n=87; plasma, n=81). Effective haemostasis was achieved in 78 (90%) patients in the 4F-PCC group compared with 61 (75%) patients in the plasma group, demonstrating both non-inferiority and superiority of 4F-PCC over plasma (difference 14·3%, 95% CI 2·8-25·8). Rapid INR reduction was achieved in 48 (55%) patients in the 4F-PCC group compared with eight (10%) patients in the plasma group, demonstrating both non-inferiority and superiority of 4F-PCC over plasma

  5. Assessment of thrombogenicity of activated and non-activated prothrombin concentrates in a rat model.

    PubMed Central

    Silberman, S.; Fareed, J.; Walenga, J.

    1986-01-01

    In vitro clotting activity of rats injected with different preparations of prothrombin concentrates was measured. Animals rendered deficient in vitamin K-dependent coagulation factors by early coumadin (warfarin) pretreatment, followed by injections of concentrate preparations were also evaluated. Findings indicate a dose-related response in abnormal coagulation changes demonstrable with each preparation and lack of protection of intravascular coagulation by coumadin anticoagulation. Furthermore, a role for in vivo factor VII activation of haemostasis following concentrate administration could not be elicited. PMID:3091059

  6. Antibodies to phosphatidylserine/prothrombin complex as an additional diagnostic marker of APS?

    PubMed

    Žigon, P; Čučnik, S; Ambrožič, A; Sodin Šemrl, S; Kveder, T; Božič, B

    2012-06-01

    Antiprothrombin antibodies can be measured by ELISA using either a prothrombin/phosphatidylserine complex (aPS/PT) or prothrombin alone (aPT) as antigen. We aimed to compare the clinical features of autoimmune patients with avidity of aPS/PT and determine the diagnostic efficiency of aPS/PT and aPT for assessing antiphospholipid syndrome (APS). aPS/PT were of low (n = 9), heterogeneous (n = 31) and high (n = 8) avidity out of 48 cases. None of the samples with low avidity were positive in aPT ELISA. Among patients with heterogeneous or high avidity aPS/PT, there was a significantly greater number of patients with APS as compared to patients with low avidity (38/39 vs. 7/9; p < 0.05). No SLE patients had high avidity antiprothrombin antibodies.

  7. Diagnostic value of antibodies to phosphatidylserine/prothrombin complex for antiphospholipid syndrome in Chinese patients.

    PubMed

    Zhu, Lei; Li, Chun; Liu, Na; Yang, Xin; Jia, R L; Mu, Rong; Su, Yin; Li, Z G

    2017-02-01

    To evaluate the diagnosis value of antibodies to phosphatidylserine/prothrombin complex (aPS/PT) in patients with antiphospholipid syndrome (APS) and to determine the clinical features of APS patients with avidity of aPS/PT. Serum samples were collected from 108 APS patients. Sixty patients with pregnancy morbidity, 37 patients with thrombosis without a history of autoimmune diseases, and 89 healthy blood donors were included as the control group. The enzyme-linked immunosorbent assay (ELISA) test was performed to detect the concentration of aPS/PT, including IgG/M, IgG, and IgM forms, in the same serum sample. The chi-square (χ2) test was used to examine the difference of frequencies of antibodies in APS patients and patients with other diseases. Spearman correlation analysis was performed to investigate the relationship between aPS/PT and other clinical/laboratory parameters. aPS/PT was detectable in 68 (63.0%) of the 108 APS patients, 12 (13.2%) of the 91 disease control patients and 1 (1.1%) of the healthy controls. It was strongly correlated with the activity of lupus anticoagulant (LA) (OR 15.952, 95% CI 7.132-35.678; P < 0.001). The frequency of aPS/PT was 56.9% in anti-cardiolipid antibody (aCL)-negative, 60.5% anti-β2 glycoprotein I antibody (aβ2GPI)-negative, and 50.0% in both aCL and aβ2GPI negative APS patients. The IgG aPS/PT was significantly associated with arterial and venous thrombosis. The aPS/PT antibody could play an important role in the diagnosis of APS, especially in patients with negative aCL and aβ2GPI. It was positively related to thrombotic events in APS.

  8. Prevalence of antibodies to prothrombin in solid phase (aPT) and to phosphatidylserine-prothrombin complex (aPS/PT) in patients with and without lupus anticoagulant.

    PubMed

    Bertolaccini, Maria Laura; Sciascia, Savino; Murru, Veronica; Garcia-Fernandez, Cesar; Sanna, Giovanni; Khamashta, Munther A

    2013-02-01

    Antibodies to prothrombin in solid phase (aPT) and those to phosphatidiyserine-prothrombin complex (aPS/PT) have been suggested to strongly correlate with the presence of lupus anticoagulant (LA). As their clinical diagnostic value and true relationship with the LA remains elusive, we designed this study to evaluate the prevalence and significance of aPT and aPS/PT in a large cohort of patients with and without LA. Samples from 257 patients were included. aPT and aPS/PT were tested by ELISA. LA was tested as per the current criteria from the ISTH Subcommittee on LA-Phospholipid-dependent antibodies. aPS/PT and aPT were found in 51% and 32% of LA-positive (LA+ve) patients and in 22% and 28% of LA-negative (LA-ve) patients, respectively. Thrombosis, particularly venous thrombosis was associated with IgG aPT in the LA+ve group (p=0.0006) and in the LA-ve group (p=0.017). Antibodies to phosphatidylserine-prothrombin, either IgG and IgM were associated with thrombosis in general (p=0.0003) in particularly with venous thrombosis in the LA+ve group (p<0.0001 for IgG and p=0.025 for IgM; respectively) and the LA-ve group (p=0.028, 0.02 and 0.001, respectively). Further multivariate logistic regression analysis showed that LA and of IgG and/or IgM aPS/PT were independent risk factors for thrombosis and pregnancy loss. In conclusion, aPS/PT, but not aPT, are more frequently found in patients with LA. Their association with thrombosis seems to be independent of the presence of LA.

  9. False Prolongation of Prothrombin Time in the Presence of a High Blood Concentration of Daptomycin.

    PubMed

    Yamada, Tomoyuki; Kato, Ryuji; Oda, Kazutaka; Tanaka, Hidema; Suzuki, Kaoru; Ijiri, Yoshio; Ikemoto, Toshiyuki; Nishihara, Masami; Hayashi, Tetsuya; Tanaka, Kazuhiko; Tamai, Hiroshi; Ukimura, Akira; Katsumata, Takahiro

    2016-10-01

    Prothrombin time (PT) can reportedly be falsely prolonged by the antimicrobial drug daptomycin (DAP), and concomitant use of phosphatidylglycerol (PG). Although high doses of DAP (>6 mg/kg/day) are recommended for severe infection and result in a high blood concentration, the extent to which high blood concentrations of DAP interfere with PT, in the presence or absence of PG, has yet to be determined when using the HemosIL RecombiPlasTin 2G (Werfen Japan, Tokyo, Japan). We examined the effects of high doses of DAP on PT using this reagent. DAP (0-500 mg/L) was added to normal plasma and plasma with an already prolonged PT in the presence or absence of liposomal amphotericin B (L-AMB, 5-50 mg/L) or COATSOME EL-01 empty cationic liposomes (CS, 25-250 mg/L). Furthermore, we undertook a Monte Carlo simulation to calculate the probability of achieving DAP concentrations >100, >200 and >500 mg/L 0-48 hr after administering 6-12 mg/kg of DAP. Apparent PT increased with increasing DAP concentration, but neither L-AMB nor CS appeared to further elevate PT when co-administered with DAP. The probability of achieving DAP concentrations >100 and >200 mg/L increased with DAP dose. Higher doses of DAP than the approved dose caused false prolongation of PT. PT should be monitored carefully in patients taking high doses of DAP; ideally, PT should be measured at the trough blood concentration of DAP. Concomitant use of L-AMB and CS did not generally further elevate PT when co-administered with DAP.

  10. Antibodies to Phosphatidylserine/Prothrombin Complex in Antiphospholipid Syndrome: Analytical and Clinical Perspectives.

    PubMed

    Peterson, Lisa K; Willis, Rohan; Harris, E Nigel; Branch, Ware D; Tebo, Anne E

    2016-01-01

    Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thrombosis and/or pregnancy-related morbidity accompanied by persistently positive antiphospholipid antibodies (aPL). Current laboratory criteria for APS classification recommend testing for lupus anticoagulant as well as IgG and IgM anticardiolipin, and beta-2 glycoprotein I (anti-β2GPI) antibodies. However, there appears to be a subset of patients with classical APS manifestations who test negative for the recommended criteria aPL tests. While acknowledging that such patients may have clinical features that are not of an autoimmune etiology, experts also speculate that these "seronegative" patients may test negative for relevant autoantibodies as a result of a lack of harmonization and/or standardization. Alternatively, they may have aPL that target other antigens involved in the pathogenesis of APS. In the latter, autoantibodies that recognize a phosphatidylserine/prothrombin (PS/PT) complex have been reported to be associated with APS and may have diagnostic relevance. This review highlights analytical and clinical attributes associated with PS/PT antibodies, taking into consideration the performance characteristics of criteria aPL tests in APS with specific recommendations for harmonization and standardization efforts.

  11. Anti-phosphatidylserine-prothrombin complex antibodies in patients with localized scleroderma.

    PubMed

    Hasegawa, M; Fujimoto, M; Hayakawa, I; Matsushita, T; Nishijima, C; Yamazaki, M; Takehara, K; Sato, S

    2006-01-01

    Although some antiphospholipid antibodies (Abs) are found in patients with localized scleroderma (LSc), Ab against phosphatidylserine-prothrombin complex (PS/PT) has not been examined. We investigated anti-PS/PT Ab levels in patients with LSc. IgG anti-PS/PT Ab levels in serum samples taken from patients with LSc (n = 42) were measured using ELISA. IgG anti-PS/PT Ab was detected in 17% of the LSc patients, while it was not detected in any normal controls (n = 32) or psoriasis vulgaris (n = 25), and this frequency was similar to that of systemic sclerosis (17%, n = 41). Among 3 LSc subgroups, generalized morphea, the severest form of LSc, had a frequency (27%) comparable with that of systemic lupus erythematosus (32%, n = 25). Among 7 LSc patients with anti-PS/PT Ab, 2 developed symptomatic thromboembolism (A 70-year-old man developed deep vein thrombosis and pulmonary infarction, although he was negative for other antiphospholipid Abs. A 6-year-old boy positive for lupus anticoagulant had cerebral infarction). By contrast, symptomatic thromboembolism was not detected in 35 LSc patients without anti-PS/PT Ab. Patients with LSc, especially generalized morphea, exhibit anti-PS/PT Ab at a frequency comparable with collagen diseases such as systemic sclerosis and systemic lupus erythematosis. Examination of this Ab may be useful to recognize the risk of thromboembolism in patients with LSc.

  12. Effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration on canine plasma samples

    PubMed Central

    Casella, Stefania; Giannetto, Claudia; Giudice, Elisabetta

    2010-01-01

    The present study was to assess the effect of storage conditions on prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen concentration in blood samples of healthy dogs. Thirty-five dogs of various breeds were included in the study. Citrated blood samples were obtained and plasma was divided into four aliquots to assess selected clotting parameters by means of a coagulometer. The first aliquot was analysed within 1 h after collection, while the remaining 3 were stored at 8℃ for 4, 8 and 24 h, respectively. One-way repeated measures analysis of variance documented a significant decreasing effect on PT at 24 h compared to 8 h and on fibrinogen concentration after 8 and 24 h compared to sampling time and at 4 and 24 h compared to 8 h post sampling. In conclusion, the results of this study indicate that only fibrinogen appears prone to significant decrease. In fact, aPTT is not substantially affected by refrigeration for at least 24 h post sampling and PT showed a statistical difference that does not necessary indicate biological significance as the results obtained were within reference intervals for the dog. PMID:20458152

  13. Presence of anti-phosphatidylserine-prothrombin complex antibodies and anti-moesin antibodies in patients with polyarteritis nodosa.

    PubMed

    Okano, Tatsuro; Takeuchi, Sora; Soma, Yoshinao; Suzuki, Koya; Tsukita, Sachiko; Ishizu, Akihiro; Suzuki, Kazuo; Kawakami, Tamihiro

    2017-01-01

    We measured both serum anti-phosphatidylserine-prothrombin complex (anti-PSPT) antibodies and anti-moesin antibodies, as well as various cytokines (interleukin [IL]-2, IL-4, IL-5, IL-10, IL-13, IL-17, granulocyte macrophage colony-stimulating factor, γ-interferon, tumor necrosis factor-α) levels in polyarteritis nodosa (PAN) patients with cutaneous manifestations. All patients showed the presence of a histological necrotizing vasculitis in the skin specimen. They were treated with i.v. cyclophosphamide pulse therapy (IV-CY) and prednisolone therapy or steroid pulse therapy. The immunological assessments were performed on sera collected prior to and after treatment with IV-CY or steroid pulse therapy. We found a significant positive correlation between serum anti-moesin antibodies and both clinical Birmingham Vasculitis Activity Scores and Vasculitis Damage Index. Anti-PSPT antibody and IL-2 levels after treatment in PAN patients were significantly lower than before treatment. In contrast, anti-moesin antibody levels were higher following IV-CY or steroid pulse therapy compared with the pretreatment levels. In the treatment-resistant PAN patients (n = 8), anti-PSPT antibody levels after treatment were significantly lower than before treatment. In contrast, anti-moesin antibody levels after treatment in the patients were significantly higher compared with the pretreatment levels. Immunohistochemical staining revealed moesin overexpression in mainly fibrinoid necrosis of the affected arteries in the PAN patients. We suggest that measurement of serum anti-PSPT antibody levels could serve as a marker for PAN and aid in earlier diagnosis of PAN. We also propose that elevated serum anti-moesin antibodies could play some role of the exacerbation in patients with PAN. © 2016 Japanese Dermatological Association.

  14. Elevated levels of antibodies against phosphatidylserine/prothrombin complex and/or cardiolipin associated with infection and recurrent purpura in a child: a forme fruste of antiphospholipid syndrome?

    PubMed

    Kinoshita, Yuri; Mayumi, Nobuko; Inaba, Motoyuki; Igarashi, Touru; Katagiri, Ichigen; Kawana, Seiji

    2015-07-15

    Antiphospholipid syndrome is an autoimmune disorder characterized by the occurrence of venous and arterial thrombosis, as well as morbidity in pregnancy, in the presence of anti-phospholipid antibodies. The diagnosis of antiphospholipid syndrome is usually established based on clinical and laboratory findings by strictly following the 2006 Sapporo classification. However, the diagnosis remains challenging owing to the ongoing debates on the serological criteria. We report a case we describe as forme fruste antiphospholipid syndrome in which these criteria were not fulfilled. Purpura appeared repeatedly in a female infant starting from the age of 6 months and following episodes of upper respiratory infections and vaccinations. The levels of anti-cardiolipin IgG antibodies and anti-phosphatidylserine/prothrombin complex antibodies were elevated in accordance with these events. Histopathological evaluation revealed multiple small vessel thrombi in the dermis and adipose tissue. After 2 weeks of treatment with aspirin and heparin, the cutaneous symptoms subsided. Infection has long been associated with antiphospholipid syndrome, and anti-phosphatidylserine/prothrombin antibodies are considered a new marker for the diagnosis of antiphospholipid syndrome. Forme fruste antiphospholipid syndrome should be considered even if the antiphospholipid syndrome diagnostic criteria are not completely fulfilled, especially in the presence of elevated levels of anti-phosphatidylserine/prothrombin antibodies and known preceding infections.

  15. Determining the effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration in rat plasma samples.

    PubMed

    Goyal, Vinod Kumar; Kakade, Somesh; Pandey, Santosh Kumar; Gothi, Anil Kalidas; Nirogi, Ramakrishna

    2015-10-01

    Coagulation parameters are usually included in clinical and preclinical safety studies to evaluate the effect of xenobiotics on the extrinsic or intrinsic pathways of coagulation. The analysis is generally performed at the time of terminal sacrifice where many activities are scheduled. Chances of delay in analysis are likely particularly when blood is collected for coagulation via the abdominal vena cava. This experiment was planned to assess the variations in coagulation parameters caused by delay in analysis as well as by storage conditions. Blood was collected from the posterior vena cava under isoflurane anesthesia, and the plasma was separated immediately. Coagulation parameters were evaluated at 0, 6, 24 and 48 h from the plasma stored at room temperature, as well as plasma stored under refrigerated and freezing conditions. Stability of the analytes in blood was also evaluated under refrigerated conditions for 6 h. All parameters were analyzed using a semi-automated coagulometer. Prothrombin time (PT) was stable under all three storage conditions for up to 6 h. Although statistically significant differences were observed for activated partial thromboplastin time (APTT) at room and refrigeration temperatures for up to 6 h, the difference was clinically non-relevant. Fibrinogen was found to be the most stable parameter that showed consistency in results even up to 48 h under all three storage conditions. Plasma for PT can be stored and analyzed without any significant changes for up to 6 h from the actual blood collection, while fibrinogen level testing can be extended for up to 48 h after collection under any storage condition. For reliable APTT results, plasma samples should be run immediately after collection.

  16. [Prothrombin fragment 1+2 (F1+2), thrombin-antithrombin III complex(TAT) and thrombophilia parameters in orally anticoagulated patients with inferior vena cava filters].

    PubMed

    Halbmayer, W M; Haushofer, A; Toth, E

    1993-01-01

    Prothrombin fragment 1 + 2 (F1 + 2) and thrombin-antithrombin-III-complex (TAT) levels were compared in 31 orally anticoagulated patients with inferior vena caval filters and a control group of 31 orally anticoagulated patients without caval filters and the incidence of markers of thrombophilia (deficiency of antithrombin-III, protein C, protein S and factor XII, presence of lupus anticoagulants) was determined. 8 of 31 patients (26%) from the group of caval filter carriers showed markers of thrombophilia (3 protein S deficiencies, 1 protein C deficiency, 2 factor XII deficiencies and 2 patients with lupus anticoagulants). In all orally anticoagulated patients a significant interdependence (p < 0.05) between F1 + 2- and TAT-levels and intensity (INR) of the oral anticoagulation could be observed. Comparison of F1 + 2- and TAT-levels of caval filter carriers and controls revealed no significant difference which leads to the conclusion that inferior vena caval filters do not induce detectable systemic activation of prothrombin under adequate oral anticoagulation therapy.

  17. Prothrombin time (PT)

    MedlinePlus

    ... Pro-time; Anticoagulant-prothrombin time; Clotting time: protime; INR; International normalized ratio ... time, results are given as what is called INR (international normalized ratio). If you are not taking ...

  18. Antibodies to phosphatidylserine/prothrombin complex in suspected antiphospholipid syndrome in the absence of antibodies to cardiolipin or Beta-2-glycoprotein I.

    PubMed

    Sanfelippo, M J; Joshi, A; Schwartz, Sl; Meister, J A; Goldberg, J W

    2013-11-01

    Antibodies to phosphatidylserine/prothrombin (aPS/PT) complex were measured in 728 serum specimens from patients suspected of having antiphospholipid syndrome (APS), but without diagnostic elevations in the levels of antibodies to cardiolipin or Beta-2 Glycoprotein 1 (β2-GP1). Of the 728 specimens, 41 had elevated levels of aPS/PT. Thrombotic events occurred in 11 of the 22 patients with accessible medical histories. Six of the patients with accessible medical records also had laboratory evidence of the lupus anticoagulant. The identification of aPS/PT in patients without evidence of antibodies to cardiolipin, β2-GP1, or the lupus anticoagulant can contribute to the identification of APS in patients that may go undetected with current testing methods.

  19. Thrombin Generation Capacity of Prothrombin Complex Concentrate in an In Vitro Dilutional Model

    PubMed Central

    Grottke, Oliver; Rossaint, Rolf; Henskens, Yvonne; van Oerle, Rene; ten Cate, Hugo; Spronk, Henri M. H.

    2013-01-01

    Background The use of PCC for the treatment of trauma-induced coagulopathy potentially increase the risk of thromboembolism and disseminated intravascular coagulation, which is addressed to an imbalance of both pro- and anticoagulants. As PCCs differ in composition, we used an in vitro dilutional approach to assess the overall thrombin generation of five different PCCs through various laboratory assays. Methods The vitamin K-dependent coagulation factors, heparin, and antithrombin were assessed in five commercially available PCCs. The procoagulant potential of the PCCs was assessed in plasma and whole blood from 4 healthy donors by means of classical coagulation assays, thrombin generation assay and thromboelastometry. In order to reflect coagulopathy, whole blood was diluted to 80, 60, 40, and 20% with Ringer’s lactate solution. Results The five different PCCs were characterised by comparable levels of factors II, VII, IX and X (all around 20–30 IU/mL), whereas the heparin (0 to 17.6 IU/mL) and antithrombin (0.06 to 1.29 IU/mL) levels were remarkably different between manufactures. In vitro dilution of blood induced a prolongation of the PT and aPTT, and attenuation of thrombin generation and ExTem induced thromboelastometry. Overall, non- or low-heparin containing PCCs restored the in vitro dilutional coagulopathy, whereas PCCs containing heparin have an anticoagulant effect. The thrombin generation assay showed to be the most sensitive method for assessment of PCC effects. Conclusions This study shows that most available PCCs are not balanced regarding their pro- and anticoagulants. The effect of measured differences in thrombin generation among different PCCs requires further investigations to elaborate the clinical meaning of this finding in the treatment of trauma induced coagulopathy. PMID:23696866

  20. Fixed Versus Variable Dosing of 4-factor Prothrombin Complex Concentrate for Emergent Warfarin Reversal

    ClinicalTrials.gov

    2017-04-24

    Acute Bleeding on Long-Term Anticoagulation Therapy; Hemorrhage; Significant Bleeding in Patients With a Coagulopathy (Prolonged Thrombin Time); Urgent Reversal of Vitamin K Antagonist (VKA) Anticoagulation

  1. Congenital prothrombin deficiency.

    PubMed

    Lancellotti, Stefano; De Cristofaro, Raimondo

    2009-06-01

    Prothrombin deficiency is among the rarest inherited coagulation disorders, with a prevalence of approximately 1:2,000,000. Two main phenotypes can be distinguished: (1) hypoprothrombinemia (type I deficiency), characterized by concomitantly low levels of activity and antigen; and (2) dysprothrombinemia (type II deficiency), characterized by the normal or near-normal synthesis of a dysfunctional protein. In some cases, hypoprothrombinemia associated with dysprothrombinemia was also described in compound heterozygous defects. No living patient with undetectable plasma prothrombin has been reported to date. Prothrombin is encoded by a gene of approximately 21 kb located on chromosome 11 and containing 14 exons. Forty different mutations have been identified and characterized in prothrombin deficiency. Many of them surround the catalytic site, whereas another "hot spot" is localized in the recognition domain called anion binding exosite I, also called fibrinogen recognition site. Recently, mutations were identified also in the Na (+)-binding loop and in the light A-chain of thrombin. Most hypoprothrombinemia-associated mutations are missense, but there are also nonsense mutations leading to stop codons and one single nucleotide deletion. Finally, the main aspects of clinical manifestations and therapy of congenital prothrombin deficiency are presented and discussed.

  2. Low paediatric thrombin generation is caused by an attenuation of prothrombin conversion.

    PubMed

    Kremers, Romy M W; Wagenvoord, Rob J; de Laat, H Bas; Monagle, Paul; Hemker, H Coenraad; Ignjatovic, Vera

    2016-06-02

    Thrombin generation (TG) is decreased in children. TG is determined by two underlying processes: the conversion of prothrombin to thrombin and the inactivation of thrombin. Therefore, lower TG capacity in children can either be caused by a reduction of prothrombin conversion, an increase of thrombin inactivation, or both. In 36 children and 8 adults, TG and the factors that determine thrombin inactivation (antithrombin, α2Macroglobulin (α2M) and fibrinogen) were measured. Prothrombin conversion, thrombin inhibitor complex formation, and the overall thrombin decay capacity were determined. In silico modelling was performed to determine the contribution prothrombin conversion and thrombin inactivation to deviant paediatric TG. Both the amount of prothrombin converted and the maximal prothrombin conversion rate are significantly reduced in children as compared to adults. This is partly due to the prothrombin levels being lower and partly to a lower prothrombin conversion rate. The overall thrombin decay capacity is not significantly different in children, but α2Macroglobulin plays a more important role than it does in adults. In silico experiments demonstrate that reduced prothrombin conversion and to a lesser extent elevated α2M levels provide an explanation for low TG in children. Young age has a dual effect on prothrombin conversion. Lower plasma prothrombin levels result in decreased prothrombin conversion but the rate of prothrombin conversion is also decreased, i. e. the development of prothrombinase is lower than in adults.

  3. [Changes in antithrombin III, prothrombin fragment 1 + 2 and thrombin-antithrombin III complex following implantation of a coronary Palmaz-Schatz stent].

    PubMed

    Dittel, M; Haushofer, A; Spiel, R; Halbmayer, W M; Prachar, H; Fischer, M; Mlczoch, J

    1995-01-01

    To detect changes in the clotting parameters antithrombin III (AT III), prothrombin-fragment 1 + 2 (F 1 + 2) and thrombin-antithrombin-III-complex (TAT) after implantation of Palmaz Schatz stents, coagulation was monitored at standardized time points in 35 patients for 10 days. All patients were anticoagulated using a combination of heparin, phenprocoumon, and acetyl salicylic acid. Heparin therapy was guided by APTT levels (normal range 25-35 s), which were still within the therapeutic range (median 49.6 s (25%/75% percentiles 41.6/54.4) on day 10. Simultaneous oral anticoagulation was found to be effective on day 8 on average (INR median 2.24 (1.93/2.50)). The AT III activity dropped significantly (p < 0.0001) after a heparin loading dose of 15,000 IU during stenting. As the heparin dose was reduced on the following days, AT III levels increased significantly (p < 0.0001) during the observation time. There was a highly significant (p < 0.001) negative correlation between AT III and heparin levels. On days 4 and 5 F 1 + 2 values were significantly (p < 0.001 and p < 0.05) higher than on the day of stenting (median 1.07 (0.90/1.31) 1.13 nmol/l and 1.06 (0.85/1.23) nmol/l vs. 0.97 (0.69/1.15) nmol/l) and dropped during anticoagulation. F 1 + 2 levels showed a significant negative correlation (p < 0.0005) with APTT values. TAT values showed no significant changes during the observation period.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Prothrombin Segovia: a new congenital abnormality of prothrombin.

    PubMed

    Rocha, E; Paramo, J A; Bascones, C; Fisac, P R; Cuesta, B; Fernandez, J

    1986-05-01

    A family with a new congenital dysprothrombinemia is presented. The propositus is a 21-yr-old man who presented simultaneously with hemartrosis of the left knee and an extensive hematoma following a minor trauma. Prothrombin time and activated partial thromboplastin time were prolonged. Prothrombin activity was very low when measured by biological assay using physiological activators (7% by one-stage method and 20% by two-stage method) or a Russel's viper venom-cephalin mixture (23%), Notechis scutatus scutatus venom (15%) and Echis carinatus venom (17%); in contrast, the level was found to be borderline to normal using Taipan viper venom (64%) and normal by both staphylocoagulase and immunologic methods. Family studies revealed consanguinity between the propositus' mother and father and both presented a 50% reduced prothrombin level when physiological activators or Echis carinatus viper venom were used. A line of identity between normal and abnormal prothrombin was observed on immunodiffusion. The migration of the abnormal prothrombin was less anodic and was not changed by the addition of calcium. The patient's serum showed 3 bands in the bidimensional immunoelectrophoresis system, whereas normal serum showed only 2 bands. The term prothrombin Segovia is proposed to define this new prothrombin abnormality.

  5. Genetics Home Reference: prothrombin deficiency

    MedlinePlus

    ... II deficiency University of Iowa Health Care: Prothrombin Gene Mutation (PDF) Patient Support and Advocacy Resources (2 links) Canadian Hemophilia Society National Hemophilia Foundation: Factor II Deficiency ClinicalTrials. ...

  6. Genetics Home Reference: prothrombin thrombophilia

    MedlinePlus

    ... with prothrombin thrombophilia . These factors include increasing age, obesity, trauma, surgery, smoking, the use of oral contraceptives ( ... Accessibility FOIA Viewers & Players U.S. Department of Health & Human Services National Institutes of Health National Library of ...

  7. Oral contraceptives and the prothrombin time.

    PubMed

    Pangrazzi, J; Roncaglioni, M C; Donati, M B

    1980-02-02

    Dr. De Teresa and others reported that mean prothrombin time ratio of 12 patients on long-term anticoagulation with warfarin was significantly higher when they were also taking oral contraceptives (OCs). A study of prothrombin complex activity was recently conducted in female rats treated with an estrogen-progestogen combination (lynestrenol 5 mg; mestranol 0.3 mg/kg body weight) which resulted in a 100% infertility in this species. After 1 treatment for only 1 estral cycle, OC-treated rats had a significantly longer Normotest clotting time (37.7+ or-0.5 sec) than control rats (31.0+or-0.4); the difference was even more notable after 10 cycles. Although this finding has not been reported in women on OCs, it may be that the estrogen-induced "lability" of the prothrombin complex occurs in humans only in special conditions, such as anticoagulation. Alternatively, liver dysfunction occurring among women on OCs may be responsible for reduced metabolism of warfarin, contributing to the effectiveness of the anticoagulation. Further pharmacology studies should be done to clarify the interaction between OCs and oral anticoagulants.

  8. Structure/function relationships of bovine prothrombin fragment 1

    SciTech Connect

    Pollock, J.S.

    1987-01-01

    The objective of this investigation was to evaluate the unique contribution of the N-terminal 33 residues of prothrombin, the Gla domain, to the Ca(II) and phospholipid binding properties of prothrombin. Prothrombin fragment 1 contains the Gla domain and is often used to study the Ca(II) and phospholipid binding properties of prothrombin. Two Gla domain peptides, 1-42 and 1-45, produced by chymotryptic cleavage of F-1 and isolated by anion-exchange chromatography were utilized to characterize the Gla domain of prothrombin. All experiments with Gla domain peptides was conducted at Ca(II) concentrations less than 2 mM since these peptides will precipitate from the solution at Ca(II) concentrations greater than 2 mM. Examinations of the properties of the Gla domain peptides was undertaken by several experimental approaches. In contrast to F-1, the intrinsic fluorescence of both 1-42 and 1-45 was not quenched upon the addition of 1 mM Ca(II) or any concentration of Mg(II). Equilibrium dialysis studies indicated that 1-42 binds three Ca(II) ions non-cooperatively. Similar studies using F-1 have shown positive cooperativity and seven Ca(II) ion binding sites. Gel permeation chromatography revealed that radioiodinated 1-45 dimerizes at the peptide concentration utilized in the equilibrium dialysis studies.

  9. A reduction of prothrombin conversion by cardiac surgery with cardiopulmonary bypass shifts the haemostatic balance towards bleeding.

    PubMed

    Kremers, Romy M W; Bosch, Yvonne P J; Bloemen, Saartje; de Laat, Bas; Weerwind, Patrick W; Mochtar, Bas; Maessen, Jos G; Wagenvoord, Rob J; Al Dieri, Raed; Hemker, H Coenraad

    2016-08-30

    Cardiac surgery with cardiopulmonary bypass (CPB) is associated with blood loss and post-surgery thrombotic complications. The process of thrombin generation is disturbed during surgery with CPB because of haemodilution, coagulation factor consumption and heparin administration. We aimed to investigate the changes in thrombin generation during cardiac surgery and its underlying pro- and anticoagulant processes, and to explore the clinical consequences of these changes using in silico experimentation. Plasma was obtained from 29 patients undergoing surgery with CPB before heparinisation, after heparinisation, after haemodilution, and after protamine administration. Thrombin generation was measured and prothrombin conversion and thrombin inactivation were quantified. In silico experimentation was used to investigate the reaction of patients to the administration of procoagulant factors and/or anticoagulant factors. Surgery with CPB causes significant coagulation factor consumption and a reduction of thrombin generation. The total amount of prothrombin converted and the rate of prothrombin conversion decreased during surgery. As the surgery progressed, the relative contribution of α2-macroglobulin-dependent thrombin inhibition increased, at the expense of antithrombin-dependent inhibition. In silico restoration of post-surgical prothrombin conversion to pre-surgical levels increased thrombin generation excessively, whereas co-administration of antithrombin resulted in the normalisation of post-surgical thrombin generation. Thrombin generation is reduced during surgery with cardiopulmonary bypass because of a balance shift between prothrombin conversion and thrombin inactivation. According to in silico predictions of thrombin generation, this new balance increases the risk of thrombotic complications with prothrombin complex concentrate administration, but not if antithrombin is co-administered.

  10. Laser-induced europium(III) luminescence as a probe of the metal ion mediated association of human prothrombin with phospholipid.

    PubMed

    Rhee, M J; Horrocks, W D; Kosow, D P

    1982-09-14

    7F0 leads to 5D0 excitation spectroscopy of Eu(III) has been used to investigate the Eu(III) and phospholipid binding properties of human prothrombin. The results indicate that human prothrombin contains four high-affinity Eu(III) binding sites which are distributed into two classes of binding sites. When 4 equiv of Eu(III) is bound to prothrombin, the prothrombin is capable of binding to phospholipid vesicles. The deuterium isotope effect on the lifetime of the Eu(III)-prothrombin complex and the Eu(III)-prothrombin-phospholipid complex was used to determine the number of water molecules coordinated to the Eu(III). In both complexes, each of the Eu(III)'s coordinated to 2.5 +/- 0.5 water molecules. These results indicate that the binding of the Eu(III)-prothrombin complex to the phospholipid does not require the formation of a prothrombin-Eu(III)-phospholipid bridge.

  11. Purification and properties of prothrombin modified by asbestos filtration of human plasma.

    PubMed

    Izuchi, Y; Boffa, M C; Soulier, J P

    1979-02-15

    Filtration through asbestos filter (Seitz) of human plasma modified the prothrombin molecule as previously shown. Factor II could no longer be activated by physiological activators (Ca++ + phospholipid + V and Xa) but reacted readily with staphylocoagulase. The separation and purification of the modified prothrombin allowed allowed the preparation of two fractions: A small slightly modified accessory fraction, "prothrombin-asbestos-1", lost its ability to be activated by physiological activators, and its ability to be adsorbed by barium citrate, but retained the immunological reactivity of fragment 1, as well as the mobility and molecular weight of unmodified prothrombin. A main fraction, "prothrombin-asbestos-2" appeared to be a modified prothrombin which has lost its N-terminal extremity. It was not adsorbed by barium citrate and could not be activated by physiological activators. It possessed a reduced electrophoretic mobility, as well as a reduced molecular weight (39,000), which are properties similar to those of thrombin. Both fractions 1 and 2 were devoid of thrombin activity. Asbestos was thus able to break the prothrombin molecule non enzymatically, the amputation of the N terminal extremity being responsible for the new functional and physicochemical properties of the molecule. Staphylocoagulase appeared not to need the N terminal extremity of the molecule of prothrombin to form the active thrombin-coagulase complex.

  12. 21 CFR 866.5735 - Prothrombin immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... antibodies) prothrombin aid in the diagnosis of blood-clotting disorders. (b) Classification. Class I... that consists of the reagents used to measure by immunochemical techniques the prothrombin...

  13. 21 CFR 866.5735 - Prothrombin immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... antibodies) prothrombin aid in the diagnosis of blood-clotting disorders. (b) Classification. Class I... that consists of the reagents used to measure by immunochemical techniques the prothrombin...

  14. 21 CFR 866.5735 - Prothrombin immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... antibodies) prothrombin aid in the diagnosis of blood-clotting disorders. (b) Classification. Class I... that consists of the reagents used to measure by immunochemical techniques the prothrombin...

  15. Complex concentrate pretreatment FY 1986 progress report

    SciTech Connect

    lokken, R O; Scheele, R D; Strachan, D M; Toste, A P

    1986-09-01

    After of the transuranic elements are removed from complex concentrate waste by the TRUEX process, the remaining waste will be grouted for final storage. The purpose of this project, conducted at the Pacific Northwest Laboratory (PNL), is to support a future decision to grout the complexant waste without destroying the organic contents. In work performed this year, it has been demonstrated that grouts with acceptable parameters for the Transportable Grout Facility can be made using actual waste. The acceptability of these grouts from a regulatory view seems to be less of a problem than was thought at this time last year. None of the organics found in the waste are included on the US Environmental Protection Agency's Hazardous Chemicals List. 7 refs., 12 figs., 4 tabs.

  16. Recombinant human prothrombin reduced blood loss in a porcine model of dilutional coagulopathy with uncontrolled bleeding.

    PubMed

    Hansson, Kenny M; Johansson, Karin J; Wingren, Cecilia; Fries, Dietmar; Nelander, Karin; Lövgren, Ann

    2017-04-01

    : Uncontrolled bleeding remains one of the leading causes of trauma-induced death. Treatment recommendations focus on fresh frozen plasma and blood cell transfusions, whereas plasma concentrates or single coagulation factors have been studied in recent years. The effect of recombinant human prothrombin factor II (rhFII, 8 mg/kg), activated recombinant human factor VII (rhFVIIa, 300 μg/kg), plasma-derived human fibrinogen (pdhFib) (200 mg/kg), activated prothrombin complex concentrate (aPCC, 40 IU/kg), a three-factor combination intended as a minimal PCC (8 mg/kg rhFII, 640 μg/kg recombinant human factor X (rhFX), and 12 μg/kg rhFVIIa), and vehicle were investigated in a porcine model of dilutional coagulopathy with uncontrolled bleeding. Survival time and blood loss were determined up to 120 min after induction of liver injury. Rotational thromboelastometry EXTEM coagulation time and maximum clot firmness, prothrombin time, thrombin-antithrombin complex (TAT), thrombin generation (endogenous thrombin potential, ETP) were measured at baseline, after dilution, drug administration, and end of experiment. rhFII, the three-factor combination, and aPCC significantly (P < 0.01) decreased blood loss vs. vehicle and rhFII also vs. fibrinogen (P < 0.05). Survival times increased significantly for rhFII, aPCC, rhFVIIa, and pdhFib vs. vehicle (P < 0.05), and, coagulation time, maximum clot firmness, and prothrombin time improved in all groups. TAT and ETP increased transiently for rhFII and three-factor combination, whereas persistently increased for aPCC. PdhFib and rhFVIIa did not increase TAT and ETP. rhFII decreased blood loss and improved hemostatic markers and survival. In vivo, thrombin generation (TAT) and potential to form thrombin (ETP) were transiently elevated by rhFII. Addition of rhFVIIa and rhFX to rhFII did not further improve hemostatic efficacy.

  17. Exploratory study of complexant concentrate waste processing

    SciTech Connect

    Lumetta, G.J.; Bray, L.A.; Kurath, D.E.; Morrey, J.R.; Swanson, J.L.; Wester, D.W.

    1993-02-01

    The purpose of this exploratory study, conducted by Pacific Northwest Laboratory for Westinghouse Hanford Company, was to determine the effect of applying advanced chemical separations technologies to the processing and disposal of high-level wastes (HLW) stored in underground tanks. The major goals of this study were to determine (1) if the wastes can be partitioned into a small volume of HLW plus a large volume of low-level waste (LLW), and (2) if the activity in the LLW can be lowered enough to meet NRC Class LLW criteria. This report presents the results obtained in a brief scouting study of various processes for separating radionuclides from Hanford complexant concentrate (CC) waste.

  18. FRACTIONATION OF PLASMA GLOBULIN FOR PROTHROMBIN, THROMBOKINASE, AND ACCESSORY THROMBOPLASTIN

    PubMed Central

    Milstone, J. H.

    1951-01-01

    1. Crude globulin from more than 1,000 liters of citrated bovine plasma has been used in developing a procedure for moderately large scale separation of clotting factors. Fraction A, prothrombin, kinase, and thrombin fractions were prepared. Fraction A contained both kinase and accessory thromboplastin, the latter predominating when fraction A was diluted. 2. When prothrombin was activated by kinase, the rate of thrombin production was enhanced by the addition of platelets, or brain lipid, or dilute fraction A. These accessory thromboplastins caused this acceleration only when calcium chloride was added. Even with calcium, they were not effective unless kinase was present. 3. In contrast, the action of kinase was not entirely dependent on either ionic calcium or accessory thromboplastin. The concentrated kinase fraction activated prothrombin in the presence of excess oxalate. Although kinase often contaminates highly purified thrombins, it is probably distinct from thrombin. The ratio of kinase to thrombin was 100 times as great in the kinase fraction as in the thrombin fraction. 4. The kinase fraction, diluted 45,000-fold, to protein-nitrogen concentrations as low as 0.02 microgram per ml., accelerated the conversion of crude prokinase in three-stage tests. 5. The findings are consistent with the following concept of the basic enzymatic mechanism: See PDF for Structure It is now added that calcium and accessory thromboplastin exert their effects by impinging on the basic mechanism, in a chemically secondary or indirect manner. PMID:14873922

  19. Safety of Prothombin Complex Concentrate to Control Excess Bleeding During Continuous Flow LVAD Insertion.

    PubMed

    Bradford, Chad D; Stahovich, Marcia J; Dembitsky, Walter P; Adamson, Robert M; Engelbert, John J; Perreiter, Alexandra S

    2015-01-01

    In cardiovascular surgery, hemostatic complexities require the provision of blood products to control bleeding as well as the use of a number of hemostatic agents, some of which cause significant morbidity. Among these agents is prothrombin complex concentrates (PCC), however there is no clear consensus on PCC use in cardiovascular surgery. To investigate the safety of PCC in patients undergoing left ventricular assist device (LVAD) placement, we reviewed our single institution experience to examine the incidence of thromboembolic events and a variety of hospital markers including morbidity and mortality. A retrospective review was conducted of patients who underwent LVAD placement between January 2010 and October 2012. Patients who received intraoperative PCC constituted the PCC group (n = 41) and those who did not constituted the non-PCC group (n = 27). The overall incidence of thromboembolic events at 3 months postoperative was 12 (29.3%) in the PCC group compared with six (22.2%) in the non-PCC group, respectively (p > 0.05). Morbidity did not differ between groups and one patient in the PCC group died. The intraoperative use of PCC in LVAD insertion does not appear to be associated with a significant increase in thromboembolic events; however, larger randomized trials are needed to confirm these findings.

  20. Plasma thrombin-antithrombin complex, prothrombin fragments 1 and 2, and D-dimer levels are elevated after endovascular but not open repair of infrarenal abdominal aortic aneurysm.

    PubMed

    Bailey, Marc A; Griffin, Kathryn J; Sohrabi, Soroush; Whalley, Daniel J; Johnson, Anne B; Baxter, Paul D; Ariëns, Robert A S; Scott, D Julian A

    2013-06-01

    Abdominal aortic aneurysm (AAA) is associated with hypercoagulability, evidenced by increased markers of coagulation activation, including thrombin-antithrombin complex (TAT), prothrombin fragments 1 and 2 (F1+2), and D-dimer. Our aim was to compare the effect of endovascular aneurysm repair (EVAR) and open aneurysm repair (OAR) on changes in coagulation activation markers after intervention. Consecutive patients with AAAs reaching their intervention threshold in a tertiary vascular referral unit in the United Kingdom were invited to participate. The coagulation markers TAT, F1+2, and D-dimer were measured in venous blood collected at baseline and at 5 months after intervention. A forward stepwise multiple linear regression model was used to identify whether treatment by OAR or EVAR had an effect on changes in coagulation factors, independent of significant covariates. The study included 47 patients (14 EVAR, 33 OAR; 85% men) who were a median age of 76 years (range, 69.5-80 years). Aortic diameter at intervention was 5.9 cm (range, 5.5-6.8 cm). There were no significant differences in clinical, anthropometric, or hematologic parameters between groups. At baseline, TAT (P = .13), F1+2 (P = .08), and D-dimer (P = .11) were similar in EVAR and OAR patients. Postintervention, there was a significant increase in TAT (3.0 [2.1-6.0] vs 7.2 [6.3-8.4] ng/mL; P = .03), F1+2 (242 [189-323] vs 392 [312-494] ng/mL; P = .003), and D-dimer (457 [336-615] vs 1197 [840-1509] ng/mL; P = .002) in the EVAR group. No significant changes were observed after intervention in the OAR group. AAA-related hypercoagulability persists after intervention, with increased TAT, F1+2, and D-dimer levels after EVAR. These findings suggest a potential period of increased cardiovascular risk in the postoperative period after EVAR. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  1. Randomized, Double-Blinded, Placebo-Controlled Trial of Fibrinogen Concentrate Supplementation After Complex Cardiac Surgery

    PubMed Central

    Ranucci, Marco; Baryshnikova, Ekaterina; Crapelli, Giulia Beatrice; Rahe-Meyer, Niels; Menicanti, Lorenzo; Frigiola, Alessandro

    2015-01-01

    Background Postoperative bleeding after heart operations is still a common finding, leading to allogeneic blood products transfusion. Fibrinogen and coagulation factors deficiency are possible determinants of bleeding. The experimental hypothesis of this study is that a first-line fibrinogen supplementation avoids the need for fresh frozen plasma (FFP) and reduces the need for any kind of transfusions. Methods and Results This was a single-center, prospective, randomized, placebo-controlled, double-blinded study. One-hundred sixteen patients undergoing heart surgery with an expected cardiopulmonary bypass duration >90 minutes were admitted to the study. Patients in the treatment arm received fibrinogen concentrate after protamine administration; patients in the control arm received saline solution. In case of ongoing bleeding, patients in the treatment arm could receive prothrombin complex concentrates (PCCs) and those in the control arm saline solution. The primary endpoint was avoidance of any allogeneic blood product. Patients in the treatment arm had a significantly lower rate of any allogeneic blood products transfusion (odds ratio, 0.40; 95% confidence interval, 0.19 to 0.84, P=0.015). The total amount of packed red cells and FFP units transfused was significantly lower in the treatment arm. Postoperative bleeding was significantly (P=0.042) less in the treatment arm (median, 300 mL; interquartile range, 200 to 400 mL) than in the control arm (median, 355 mL; interquartile range, 250 to 600 mL). Conclusions Fibrinogen concentrate limits postoperative bleeding after complex heart surgery, leading to a significant reduction in allogeneic blood products transfusions. No safety issues were raised. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT01471730. PMID:26037084

  2. Structural architecture of prothrombin in solution revealed by single molecule spectroscopy

    DOE PAGES

    Pozzi, Nicola; Bystranowska, Dominika; Zuo, Xiaobing; ...

    2016-07-19

    The coagulation factor prothrombin has a complex spatial organization of its modular assembly that comprises the N-terminal Gla domain, kringle-1, kringle-2, and the C-terminal protease domain connected by three intervening linkers. Here we use single molecule Förster resonance energy transfer to access the conformational landscape of prothrombin in solution and uncover structural features of functional significance that extend recent x-ray crystallographic analysis. Prothrombin exists in equilibrium between two alternative conformations, open and closed. The closed conformation predominates (70%) and features an unanticipated intramolecular collapse of Tyr93 in kringle-1 onto Trp547 in the protease domain that obliterates access to the activemore » site and protects the zymogen from autoproteolytic conversion to thrombin. The open conformation (30%) is more susceptible to chymotrypsin digestion and autoactivation, and features a shape consistent with recent x-ray crystal structures. Small angle x-ray scattering measurements of prothrombin wild type stabilized 70% in the closed conformation and of the mutant Y93A stabilized 80% in the open conformation directly document two envelopes that differ 50 Å in length. These findings reveal important new details on the conformational plasticity of prothrombin in solution and the drastic structural difference between its alternative conformations. Prothrombin uses the intramolecular collapse of kringle-1 onto the active site in the closed form to prevent autoactivation. As a result, the open-closed equilibrium also defines a new structural framework for the mechanism of activation of prothrombin by prothrombinase.« less

  3. Structural architecture of prothrombin in solution revealed by single molecule spectroscopy

    SciTech Connect

    Pozzi, Nicola; Bystranowska, Dominika; Zuo, Xiaobing; Di Cera, Enrico

    2016-07-19

    The coagulation factor prothrombin has a complex spatial organization of its modular assembly that comprises the N-terminal Gla domain, kringle-1, kringle-2, and the C-terminal protease domain connected by three intervening linkers. Here we use single molecule Förster resonance energy transfer to access the conformational landscape of prothrombin in solution and uncover structural features of functional significance that extend recent x-ray crystallographic analysis. Prothrombin exists in equilibrium between two alternative conformations, open and closed. The closed conformation predominates (70%) and features an unanticipated intramolecular collapse of Tyr93 in kringle-1 onto Trp547 in the protease domain that obliterates access to the active site and protects the zymogen from autoproteolytic conversion to thrombin. The open conformation (30%) is more susceptible to chymotrypsin digestion and autoactivation, and features a shape consistent with recent x-ray crystal structures. Small angle x-ray scattering measurements of prothrombin wild type stabilized 70% in the closed conformation and of the mutant Y93A stabilized 80% in the open conformation directly document two envelopes that differ 50 Å in length. These findings reveal important new details on the conformational plasticity of prothrombin in solution and the drastic structural difference between its alternative conformations. Prothrombin uses the intramolecular collapse of kringle-1 onto the active site in the closed form to prevent autoactivation. As a result, the open-closed equilibrium also defines a new structural framework for the mechanism of activation of prothrombin by prothrombinase.

  4. A prothrombin activator from Bothrops erythromelas (jararaca-da-seca) snake venom: characterization and molecular cloning.

    PubMed

    Silva, Márcia B; Schattner, Mirta; Ramos, Celso R R; Junqueira-de-Azevedo, Inácio L M; Guarnieri, Míriam C; Lazzari, María A; Sampaio, Claudio A M; Pozner, Roberto G; Ventura, Janaina S; Ho, Paulo L; Chudzinski-Tavassi, Ana M

    2003-01-01

    A novel prothrombin activator enzyme, which we have named 'berythractivase', was isolated from Bothrops erythromelas (jararaca-da-seca) snake venom. Berythractivase was purified by a single cation-exchange-chromatography step on a Resource S (Amersham Biosciences) column. The overall purification (31-fold) indicates that berythractivase comprises about 5% of the crude venom. It is a single-chain protein with a molecular mass of 78 kDa. SDS/PAGE of prothrombin after activation by berythractivase showed fragment patterns similar to those generated by group A prothrombin activators, which convert prothrombin into meizothrombin, independent of the prothrombinase complex. Chelating agents, such as EDTA and o -phenanthroline, rapidly inhibited the enzymic activity of berythractivase, like a typical metalloproteinase. Human fibrinogen A alpha-chain was slowly digested only after longer incubation with berythractivase, and no effect on the beta- or gamma-chains was observed. Berythractivase was also capable of triggering endothelial proinflammatory and procoagulant cell responses. von Willebrand factor was released, and the surface expression of both intracellular adhesion molecule-1 and E-selectin was up-regulated by berythractivase in cultured human umbilical-vein endothelial cells. The complete berythractivase cDNA was cloned from a B. erythromelas venom-gland cDNA library. The cDNA sequence possesses 2330 bp and encodes a preproprotein with significant sequence similarity to many other mature metalloproteinases reported from snake venoms. Berythractivase contains metalloproteinase, desintegrin-like and cysteine-rich domains. However, berythractivase did not elicit any haemorrhagic response. These results show that, although the primary structure of berythractivase is related to that of snake-venom haemorrhagic metalloproteinases and functionally similar to group A prothrombin activators, it is a prothrombin activator devoid of haemorrhagic activity. This is a feature

  5. Fibroblasts, glial, and neuronal cells are involved in extravascular prothrombin activation.

    PubMed

    Yamazaki, Y; Shikamoto, Y; Fukudome, K; Kimoto, M; Morita, T

    1999-10-01

    A membrane-associated prothrombin activator (MAPA) was found on various cultured cells derived from non-hematopoietic cells [Sekiya, F. et al. (1994) J. Biol. Chem. 269, 32441-32445]. In this study, we investigated the enzymatic properties of this enzyme using protease inhibitors. While the metalloproteinase inhibitor, o-phenanthroline, had no effect, some Kunitz type serine protease inhibitors attenuated MAPA activity. Recombinant tissue factor pathway inhibitor (rTFPI) also markedly reduced the activity (IC(50), 1. 3+/-0.6 x 10(-10) M). MAPA activity is, therefore, most likely to be due to factor Xa. We evaluated the effect of exogenous factor Xa on MAPA activity. Factor Xa-dependent prothrombin activation was observed on fibroblast cells (apparent K(d), 1.47+/-0.72 nM). Activation was also observed on glial and neuronal cells, which expressed MAPA activity. These results imply that membrane-bound factor Xa results in MAPA activity on these cells. Therefore, we considered the involvement of factor Va, a component of prothrombinase, in this activity. We examined whether or not the prothrombinase complex is assembled on these cells. Prothrombin was activated in a manner dependent on both exogenous factor Xa and factor Va (apparent K(d) of 0.51-1.81 nM for factor Va). These results indicate that the prothrombinase complex forms specifically on various extravascular cells. Although the prothrombinase complex can be assembled on monocytes and lymphocytes, it is not known why these cells can activate prothrombin specifically. These cells which have the capacity for prothrombin activator activity could also activate factor X; i.e. cells with factor X activation activity were able to convert prothrombin. These observations suggest that thrombin was generated via two procoagulant activities; factor X activation and subsequent prothrombinase complex formation on the surface of these cells. This mechanism may explain the various pathological states involving or resulting

  6. Dilutional Control of Prothrombin Activation at Physiologically Relevant Shear Rates

    PubMed Central

    Haynes, Laura M.; Dubief, Yves C.; Orfeo, Thomas; Mann, Kenneth G.

    2011-01-01

    The generation of proteolyzed prothrombin species by preassembled prothrombinase in phospholipid-coated glass capillaries was studied at physiologic shear rates (100–1000 s−1). The concentration of active thrombin species (α-thrombin and meizothrombin) reaches a steady state, which varies inversely with shear rate. When corrected for shear rate, steady-state levels of active thrombin species exhibit no variation and a Michaelis-Menten analysis reveals that chemistry of this reaction is invariant between open and closed systems; collectively, these data imply that variations with shear rate arise from dilutional effects. Significantly, the major products observed include nonreactive species arising from the loss of prothrombin's phospholipid binding domain (des F1 species). A numerical model developed to investigate the spatial and temporal distribution of active thrombin species within the capillary reasonably approximates the observed output of total thrombin species at different shears; it also predicts concentrations of active thrombin species in the wall region sufficient to account for observed levels of des FI species. The predominant feedback formation of nonreactive species and high levels of the primarily anticoagulant intermediate meizothrombin (∼40% of total active thrombin species) may provide a mechanism to prevent thrombus propagation downstream of a site of thrombosis or hemorrhage. PMID:21281592

  7. Structural transitions during prothrombin activation: On the importance of fragment 2

    PubMed Central

    Adams, Ty E.; Huntington, James A.

    2016-01-01

    Prothrombin is activated to thrombin by the prothrombinase complex through sequential cleavage at two distinct sites. This occurs at sites of vascular injury in a highly regulated cascade of serine protease and cofactor activation, where activated platelets provide a suitable surface for protease/cofactor/substrate assembly. The precise structural and conformational changes undergone during the transition from prothrombin to thrombin have been studied for decades, and several structures of prothrombin fragments along the activation pathway have been solved. Here we present a new structure analyzed in context of other recent structures and biochemical studies. What emerges is an unexpected mechanism that involves a change in the mode of binding of the F2 domain (fragment 2) on the catalytic domain after cleavage at Arg320, and a subsequent reorientation of the linker between the F2 and catalytic domain to present the Arg271 site for cleavage. PMID:26365066

  8. Global Post-Authorization Safety Surveillance Study: real-world data on prophylaxis and on-demand treatment using FEIBA (an activated prothrombin complex concentrate)

    PubMed Central

    Negrier, Claude; Voisin, Sophie; Baghaei, Fariba; Numerof, Robert; Novack, Aaron; Doralt, Jennifer E.; Romanov, Vadim; Gringeri, Alessandro

    2016-01-01

    This prospective, Post-Authorization Safety Surveillance (PASS) study was carried out in patients with hemophilia A or B and inhibitors treated with FEIBA for 1 year to collect real-world data on safety and effectiveness of FEIBA. The study followed a cohort design and did not make stipulations on treatment or observation schedule, as it was designed to observe routine medical practices based on physicians’ treatment decisions, including whether patients received on-demand or prophylaxis with FEIBA. The attending physician maintained documentation, including medical records, laboratory reports, adverse event reports, and so on and a subject diary was used. Eighty-one patients were treated with FEIBA at 40 sites in 10 countries over a 4-year period. Sixty-nine patients (85.2%) had hemophilia A, two had (2.5%) hemophilia B, and ten (12.3%) had acquired hemophilia A. At baseline 45 patients (55.6%) were prescribed prophylaxis and 36 (44.6%) on-demand treatment. This study was novel in following safety and effectiveness in ‘real world’ on-demand and prophylactic use of FEIBA, and was able to collect data in these rare patients under routine clinical practice. PMID:26829366

  9. 21 CFR 864.7750 - Prothrombin time test.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prothrombin time test. 864.7750 Section 864.7750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7750 Prothrombin...

  10. 21 CFR 864.7720 - Prothrombin consumption test.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Prothrombin consumption test. 864.7720 Section 864.7720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7720 Prothrombin...

  11. 21 CFR 864.7720 - Prothrombin consumption test.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Prothrombin consumption test. 864.7720 Section 864.7720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7720 Prothrombin...

  12. 21 CFR 864.7720 - Prothrombin consumption test.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Prothrombin consumption test. 864.7720 Section 864.7720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7720 Prothrombin...

  13. 21 CFR 864.7720 - Prothrombin consumption test.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Prothrombin consumption test. 864.7720 Section 864.7720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7720 Prothrombin...

  14. 21 CFR 866.5735 - Prothrombin immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prothrombin immunological test system. 866.5735 Section 866.5735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... vitro coagulation studies classified under § 864.5425 of this chapter or prothrombin time tests...

  15. Further evidence for two functional forms of prothrombinase each specific for either of the two prothrombin activation cleavages.

    PubMed

    Kim, Paul Y; Nesheim, Michael E

    2007-11-09

    Previous work showed that prothrombin derivatives cleavable only at Arg-320 (rMZ) or Arg-271 (rP2) are partial, rather than competitive, inhibitors of prothrombin activation by prothrombinase. A "ping-pong"-like model, which posits two equilibrating forms of prothrombinase, explained the inhibition pattern. The present studies were undertaken to further investigate this putative mechanism. Two models were developed, one allowing for one form of the enzyme and the other allowing for two forms. Both models also allowed channeling and ratcheting. The models were fit to full time courses of prothrombin, meizothrombin, prethrombin-2, and the B-chain. In the absence of ratcheting and channeling, neither model fits the data. In their presence, however, both models fit very well, and thus they could not be distinguished. Therefore, inhibition of rMZ activation by rP2 was studied. Inhibition was partial and the two-form model fit the data with randomly distributed residuals, whereas the one-form model did not. Initial rates of fluorescein-labeled prothrombin cleavage in the presence of various prothrombin derivatives reported by Brufatto and Nesheim (Brufatto, N., and Nesheim, M. E. (2003) J. Biol. Chem. 278, 6755-6764) were also analyzed using the two models. The two-form model fit the partial inhibition data well, whereas the one-form model did not. In addition, prothrombin at varying concentrations was activated, and subsequently, the initial rates were plotted with respect to the initial prothrombin concentration. When compared with the expected initial rates as determined by the simulation of the models, the two-form model fit the observed rates better than the one-form model. The results obtained here further support the existence of two functional forms of prothrombinase.

  16. Anti-prothrombin (aPT) and anti-phosphatidylserine/prothrombin (aPS/PT) antibodies and the risk of thrombosis in the antiphospholipid syndrome. A systematic review.

    PubMed

    Sciascia, Savino; Sanna, Giovanni; Murru, Veronica; Roccatello, Dario; Khamashta, Munther A; Bertolaccini, Maria Laura

    2014-02-01

    Antibodies to prothrombin are detected by directly coating prothrombin on irradiated ELISA plates (aPT) or by using the phosphatidylserine/prothrombin complex as antigen (aPS/PT). Although these antibodies have both been associated with antiphospholipid syndrome (APS) and a correlation between the two assays have been reported, it seems that aPT and aPS/PT belong to different populations of autoantibodies. It was our objective to systematically review the available evidence on aPT and aPS/PT antibodies and the risk of thrombosis in APS. Medline-reports published between 1988 and 2013 investigating aPT and aPS/PT as a risk factor for thrombosis were included. Whenever possible, antibody isotype(s) and site of thrombosis were analysed. This systematic review is based on available data from more than 7,000 patients and controls from 38 studies analysing aPT and 10 aPS/PT. Antibodies to prothrombin (both aPT and aPS/PT) increased the risk of thrombosis (odds ratio [OR] 2.3; 95% confidence interval [CI] 1.72-3.5). aPS/PT seemed to represent a stronger risk factor for thrombosis, both arterial and/or venous than aPT (OR 5.11; 95%CI 4.2-6.3 and OR 1.82; 95%CI 1.44-2.75, respectively). In conclusion, routine measurement of aPS/PT (but not aPT) might be useful in establishing the thrombotic risk of patients with previous thrombosis and/or systemic lupus erythematosus. Their inclusion as laboratory criteria for the APS should be indisputably further explored.

  17. New tests to detect antiphospholipid antibodies: antiprothrombin (aPT) and anti-phosphatidylserine/prothrombin (aPS/PT) antibodies.

    PubMed

    Sciascia, Savino; Khamashta, Munther A; Bertolaccini, Maria Laura

    2014-05-01

    Antiprothrombin antibodies have been proposed as potential new biomarkers for thrombosis and/or pregnancy morbidity in the setting of the antiphospholipid syndrome (APS). Antiprothrombin antibodies are commonly detected by ELISA, using prothrombin coated onto irradiated plates (aPT), or prothrombin in complex with phosphatidylserine (aPS/PT), as antigen. Although these antibodies can co-exist in the same patient, aPT and aPS/PT seem to belong to different populations of autoantibodies. Early research explored the role of antibodies to prothrombin as potential antigenic targets for the lupus anticoagulant (LA). To date their clinical significance is being investigated and their potential role in identifying patients at higher risk of developing thrombotic events or pregnancy morbidity is being probed.

  18. Detection of Antiphosphatidylserine/Prothrombin Antibodies and Their Potential Diagnostic Value

    PubMed Central

    Žigon, Polona; Čučnik, Saša; Ambrožič, Aleš; Kveder, Tanja; Šemrl, Snežna Sodin; Rozman, Blaž; Božič, Borut

    2013-01-01

    Antiprothrombin antibodies, measured with phosphatidylserine/prothrombin complex (aPS/PT) ELISA, have been reported to be associated with antiphospholipid syndrome (APS). They are currently being evaluated as a potential classification criterion for this autoimmune disease, characterized by thromboses and obstetric complications. Given the present lack of clinically useful tests for the accurate diagnosis of APS, we aimed to evaluate in-house and commercial assays for determination of aPS/PT as a potential serological marker for APS. We screened 156 patients with systemic autoimmune diseases for antibodies against PS/PT, β 2-glycoprotein I, cardiolipin and for lupus anticoagulant activity. We demonstrated a high degree of concordance between the concentrations of aPS/PT measured with the in-house and commercial assays. Both assays performed comparably relating to the clinical manifestations of APS, such as arterial and venous thromboses and obstetric complications. IgG aPS/PT represented the strongest independent risk factor for the presence of obstetric complications, among all tested aPL. Both IgG and IgM aPS/PT were associated with venous thrombosis, but not with arterial thrombosis. Most importantly, the association between the presence of IgG/IgM aPS/PT and lupus anticoagulant activity was highly significant. Taken together, aPS/PT antibodies detected with the in-house or commercial ELISA represent a promising serological marker for APS and its subsets. PMID:24187565

  19. Water complexes of important air pollutants: geometries, complexation energies, concentrations, infrared spectra, and intrinsic reactivity.

    PubMed

    Galano, Annia; Narciso-Lopez, Marcela; Francisco-Marquez, Misaela

    2010-05-13

    Water complexes involving methanol, ethanol, formaldehyde, formic acid, acetone, ammonia, acetylene, ethylene, chloroethene, trichloroethene, 1,1,1-trichloroethane, hydroxyl radical, and hydroperoxyl radical have been studied. Enthalpies, entropies, and Gibbs free energies of association have been estimated, as well as the concentrations of the complexes under lower-troposphere conditions. The influence of the relative air humidity on the complexation processes has been analyzed. The association processes yielding water complexes of methanol, ethanol, formic acid, ammonia, acetone, hydroxyl radical, and hydroperoxyl radical were found to be more exothermic than that of the water dimer. General trends for the reactivity of the studied water complexes, compared to those of the corresponding free species, are proposed based on global reactivity indexes. The previously reported increased reactivity of the (*)OOH self-reaction, when there is water present, has been explained. The IR spectra of the complexes have been analyzed and compared with those of the free species.

  20. Minimal selective concentrations of tetracycline in complex aquatic bacterial biofilms.

    PubMed

    Lundström, Sara V; Östman, Marcus; Bengtsson-Palme, Johan; Rutgersson, Carolin; Thoudal, Malin; Sircar, Triranta; Blanck, Hans; Eriksson, K Martin; Tysklind, Mats; Flach, Carl-Fredrik; Larsson, D G Joakim

    2016-05-15

    Selection pressure generated by antibiotics released into the environment could enrich for antibiotic resistance genes and antibiotic resistant bacteria, thereby increasing the risk for transmission to humans and animals. Tetracyclines comprise an antibiotic class of great importance to both human and animal health. Accordingly, residues of tetracycline are commonly detected in aquatic environments. To assess if tetracycline pollution in aquatic environments promotes development of resistance, we determined minimal selective concentrations (MSCs) in biofilms of complex aquatic bacterial communities using both phenotypic and genotypic assays. Tetracycline significantly increased the relative abundance of resistant bacteria at 10 μg/L, while specific tet genes (tetA and tetG) increased significantly at the lowest concentration tested (1 μg/L). Taxonomic composition of the biofilm communities was altered with increasing tetracycline concentrations. Metagenomic analysis revealed a concurrent increase of several tet genes and a range of other genes providing resistance to different classes of antibiotics (e.g. cmlA, floR, sul1, and mphA), indicating potential for co-selection. Consequently, MSCs for the tet genes of ≤ 1 μg/L suggests that current exposure levels in e.g. sewage treatment plants could be sufficient to promote resistance. The methodology used here to assess MSCs could be applied in risk assessment of other antibiotics as well. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. [Biohydrometallurgical technology of a complex copper concentrate process].

    PubMed

    Murav'ev, M I; Fomchenko, N V; Kondrat'eva, T F

    2011-01-01

    Leaching of sulfide-oxidized copper concentrate of the Udokan deposit ore with a copper content of 37.4% was studied. In the course of treatment in a sulfuric acid solution with pH 1.2, a copper leaching rate was 6.9 g/kg h for 22 h, which allowed extraction of 40.6% of copper. As a result of subsequent chemical leaching at 80 degrees C during 7 h with a solution of sulphate ferric iron obtained after bio-oxidation by an association of microorganisms, the rate of copper recovery was 52.7 g/kg h. The total copper recovery was 94.5% (over 29 h). Regeneration of the Fe3+ ions was carried out by an association of moderately thermophilic microorganisms, including bacteria of genus Sulfobacillus and archaea of genus Ferroplasma acidiphilum, at 1.0 g/l h at 40 degrees C in the presence of 3% solids obtained by chemical leaching of copper concentrate. A technological scheme of a complex copper concentrate process with the use of bacterial-chemical leaching is proposed.

  2. 21 CFR 864.7720 - Prothrombin consumption test.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prothrombin consumption test. 864.7720 Section 864.7720 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7720...

  3. Using the international normalized ratio to standardize prothrombin time.

    PubMed

    Stern, R; Karlis, V; Kinney, L; Glickman, R

    1997-08-01

    The international normalized ratio, or INR, was introduced in 1983 by the World Health Organization, or WHO, Committee on Biological Standards to more accurately assess patients receiving anticoagulation therapy. The INR mandates the universal standardization of prothrombin time. This article describes the method used to calculate INR, as well as its clinical relevance to the practice of dentistry.

  4. 21 CFR 866.5735 - Prothrombin immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Prothrombin immunological test system. 866.5735 Section 866.5735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... factor II) in serum. Measurements of the amount of antigenically competent (ability to react with protein...

  5. Kinetics of the activation of human prothrombin by human coagulation factor Xa. Initial rate studies in the presence of Ca2+ and phospholipid.

    PubMed

    Kosow, D P; Orthner, C L

    1979-10-10

    Steady state kinetic studies have been performed to investigate the formation of thrombin from prothrombin by human coagulation Factor Xa in the presence of Ca2+ and phospholipid. The concentration of ligand which gives 50% of the maximum velocity (K0.5) is 2.3 mM for Ca2+, 7.4 microM for phospholipid, and 0.006 microM for prothrombin. Hill plots of the Ca2+ enhancement of the reaction give a Hill coefficient of 3.1, indicating positive cooperativity. The initial velocity patterns are consistent with an ordered addition of reactants with phospholipid as the second reactant to bind to the enzyme. Although our results do not differentiate between Ca2+ or the prothrombin substrate as the first reactant to bind to Factor Xa, it is established that Ca2+ can bind to Factor Xa in the absence of the other reactants. Thus, the most probable order of addition of reactants is Ca2+, phospholipid, and the prothrombin substrate. Plots of (v)-1 versus (prothrombin)-1 or (v)-1 versus [(Ca2+)3]-1 at several constant concentrations of phospholipid indicate that the major effect of phospholipid is to increase the turnover number of Factor Xa.

  6. Nano concentration by acoustically generated complex spiral vortex field

    NASA Astrophysics Data System (ADS)

    Tang, Qiang; Wang, Xiaofei; Hu, Junhui

    2017-03-01

    A strategy to concentrate nanoscale materials on the boundary between a nano suspension droplet and non-vibration substrate is demonstrated and analyzed. It employs the spiral vortex of acoustic streaming, generated by an ultrasonically vibrating needle parallel to and above the non-vibration substrate. The vortex drags nanoscale materials to the center of itself, forming a concentration spot. For 250 nm-diameter SiO2 nano particle suspension with an initial concentration of 0.09 mg/ml, the diameter of the concentration spot can be up to several hundred microns. The dependency of the spiral vortex field on the vibration distribution of the acoustic needle in the droplet is also clarified by experiments and computation, and the concentration conditions are obtained by analyzing the nano particle dynamics in the spiral vortex.

  7. Temperature dependence of the thrombin-catalyzed proteolysis of prothrombin.

    PubMed

    Shi, Fang; Winzor, Donald J; Jackson, Craig M

    2004-07-01

    Measurement of the temperature-dependence of thrombin-catalyzed cleavage of the Arg(155)-Ser(156) and Arg(284)-Thr(285) peptide bonds in prothrombin and prothrombin-derived substrates has yielded Arrhenius parameters that are far too large for classical mechanistic interpretation in terms of a simple hydrolytic reaction. Such a difference from the kinetic behavior exhibited in trypsin- and chymotrypsin-catalyzed proteolysis of peptide bonds is attributed to contributions by enzyme exosite interactions as well as enzyme conformational equilibria to the magnitudes of the experimentally determined Arrhenius parameters. Although the pre-exponential factor and the energy of activation deduced from the temperature-dependence of rate constants for proteolysis by thrombin cannot be accorded the usual mechanistic significance, their evaluation serves a valuable role by highlighting the existence of contributions other than those emanating from simple peptide hydrolysis to the kinetics of proteolysis by thrombin and presumably other enzymes of the blood coagulation system.

  8. Chloridizing Roasting Process for a Complex Sulfide Concentrate

    NASA Astrophysics Data System (ADS)

    Mukherjee, T. K.; Menon, P. R.; Shukla, P. P.; Gupta, C. K.

    1985-06-01

    This paper describes a chloridizing roasting process applied to two types of nickel and copper-bearing sulfide concentrates. One was copper rich and the other nickel rich. The paper gives a full account of the process as investigated in various batch roasters, and in multiple hearth and rotary roasters. For commercial viability, the paper finally examines the rotary furnace as the preferred equipment for roasting the types of nickel-copper bearing sulfide concentrates studied here.

  9. Control of oral anticoagulant treatment by chromogenic prothrombin assay.

    PubMed Central

    O'Donnell, J R; Walker, I D; Davidson, J F

    1987-01-01

    Doses of oral anticoagulants in 50 patients on long term treatment were easily and satisfactorily monitored over six months by an automated chromogenic assay of prothrombin (CPA). It is suggested that chromogenic assay of one or more of the vitamin K dependent coagulation factors would provide a readily standardised alternative to those conventional tests which depend on human brain derived reagents, now regarded as a biohazard. PMID:3108332

  10. Antiphosphatidylserine/prothrombin antibodies (aPS/PT) as potential markers of antiphospholipid syndrome.

    PubMed

    Vlagea, Alexandru; Gil, Antonio; Cuesta, Maria V; Arribas, Florencia; Diez, Jesús; Lavilla, Paz; Pascual-Salcedo, Dora

    2013-06-01

    The antiphospholipid antibodies present in antiphospholipid syndrome (APS) are directed at a number of phospholipid-binding proteins: β2 glycoprotein I (β2GPI), prothrombin, and so on. Antibodies directed at β2GPI are accepted as a classification criterion for APS, while the presence of antiprothrombin antibodies is not. In the present article, we investigated the possible role of antiphosphatidylserine/prothrombin antibodies (aPS/PT) as marker of APS on a cohort of 295 individuals with APS (95 primary APS and 45 secondary APS) and APS-related diseases. We found aPS/PT to be highly associated with venous thrombosis (immunoglobulin G [IgG] aPS/PT odds ratio [OR], 7.44; 95% confidence interval [CI], 3.97-13.92 and IgM aPS/PT OR, 2.54; 95% CI, 1.35-4.77) and obstetric abnormalities (IgG aPS/PT OR, 2.37; 95% CI, 1.04-5.43), but not with arterial thrombosis. A very high degree of concordance between the concentration of aPS/PT and lupus anticoagulant activity was demonstrated. Therefore, we support the inclusion of aPS/PT determination as second-level assay to confirm APS classification.

  11. Complex Spontaneous Flows and Concentration Banding in Active Polar Films

    NASA Astrophysics Data System (ADS)

    Giomi, Luca; Marchetti, M. Cristina; Liverpool, Tanniemola B.

    2008-11-01

    We study the dynamical properties of active polar liquid crystalline films. Like active nematic films, active polar films undergo a dynamical transition to spontaneously flowing steady states. Spontaneous flow in polar fluids is, however, always accompanied by strong concentration inhomogeneities or “banding” not seen in nematics. In addition, a spectacular property unique to polar active films is their ability to generate spontaneously oscillating and banded flows even at low activity. The oscillatory flows become increasingly complicated for strong polarity.

  12. Staphylococcal superantigen-like protein 10 (SSL10) inhibits blood coagulation by binding to prothrombin and factor Xa via their γ-carboxyglutamic acid (Gla) domain.

    PubMed

    Itoh, Saotomo; Yokoyama, Ryosuke; Kamoshida, Go; Fujiwara, Toshinobu; Okada, Hiromi; Takii, Takemasa; Tsuji, Tsutomu; Fujii, Satoshi; Hashizume, Hideki; Onozaki, Kikuo

    2013-07-26

    The staphylococcal superantigen-like protein (SSL) family is composed of 14 exoproteins sharing structural similarity with superantigens but no superantigenic activity. Target proteins of four SSLs have been identified to be involved in host immune responses. However, the counterparts of other SSLs have been functionally uncharacterized. In this study, we have identified porcine plasma prothrombin as SSL10-binding protein by affinity purification using SSL10-conjugated Sepharose. The resin recovered the prodomain of prothrombin (fragment 1 + 2) as well as factor Xa in pull-down analysis. The equilibrium dissociation constant between SSL10 and prothrombin was 1.36 × 10(-7) M in surface plasmon resonance analysis. On the other hand, the resin failed to recover γ-carboxyglutamic acid (Gla) domain-less coagulation factors and prothrombin from warfarin-treated mice, suggesting that the Gla domain of the coagulation factors is essential for the interaction. SSL10 prolonged plasma clotting induced by the addition of Ca(2+) and factor Xa. SSL10 did not affect the protease activity of thrombin but inhibited the generation of thrombin activity in recalcified plasma. S. aureus produces coagulase that non-enzymatically activates prothrombin. SSL10 attenuated clotting induced by coagulase, but the inhibitory effect was weaker than that on physiological clotting, and SSL10 did not inhibit protease activity of staphylothrombin, the complex of prothrombin with coagulase. These results indicate that SSL10 inhibits blood coagulation by interfering with activation of coagulation cascade via binding to the Gla domain of coagulation factor but not by directly inhibiting thrombin activity. This is the first finding that the bacterial protein inhibits blood coagulation via targeting the Gla domain of coagulation factors.

  13. Lithium concentration and Li isotopic compositions of carbonatitic complexes

    NASA Astrophysics Data System (ADS)

    Halama, R.; McDonough, W. F.; Rudnick, R. L.; Ash, R. D.; Keller, J.; Klaudius, J.; Trumbull, R.

    2005-12-01

    To evaluate the Li isotopic signatures of the mantle sources of carbonatites and the influence of magmatic differentiation and post-magmatic processes on δ7Li, we determined the Li concentrations and isotopic compositions of carbonatites and spatially associated silicate rocks, spanning a wide range in composition and age. Natrocarbonatites from Oldoinyo Lengai (1995 and 2000 eruptions) have high Li concentrations (211-292 ppm) and uniform Li isotopic signatures (δ7Li = +4.4 to +5.1 per mil). Associated silicate rocks (melilitite, nephelinite and phonolite) have lower Li concentrations (16-47 ppm) and trend towards lighter Li isotopic values (δ7Li = 0 to +3.5 per mil). Clinopyroxenes from these lavas are significantly lighter than the whole rocks by 1 to 6 per mil. Since the lavas appear to be fresh, this suggests fractionation of Li isotopes between minerals and whole rocks. In comparison to the modern natrocarbonatites, Proterozoic calciocarbonatites from Greenland (Grønnedal-Ika) and Cretaceous calciocarbonatites from Namibia (Kalkfeld) are poor in Li (< 2 ppm) and have more scattered Li isotopic compositions (δ7Li = -1 to +4 and -0.5 to +5 per mil, respectively). The lower δ7Li values may reflect contamination by crustal Li, since the low Li contents in the carbonatites make them susceptible to this. Silicate lavas from Kalkfeld have higher Li concentrations (11-12 ppm) than their associated carbonatites, but overlapping isotopic compositions (δ7Li = +4 to +6 per mil). At Grønnedal-Ika, clinopyroxene separates from nepheline syenites vary considerably in δ7Li from -6 to +5. Since Li is preferentially partitioned into fenitizing fluids [1] and an enrichment of light 6Li in fluids during degassing can be anticipated [2], the trend towards negative δ7Li can be interpreted as a result of variable interaction with metasomatizing fluids. However, fractionation of Li isotopes between minerals and melts may also have played a role. Our preliminary data

  14. Kinetic and equilibrium metal-ion-binding behaviour reflected in a metal-ion-dependent antigenic determinant in bovine prothrombin. Comparison with bovine prothrombin fragment 1.

    PubMed Central

    Madar, D A; Hall, T J; Hiskey, R G; Koehler, K A

    1981-01-01

    Rabbit anti-(bovine prothrombin fragment 1) antibodies were fractionated by using fragment-1 affinity chromatography in the absence of metal ions, and showed an absolute requirement for the presence of metal ions in their interactions with bovine fragment 1 or prothrombin. These antibodies were employed to evaluate both the rate constants for a protein conformation change and the equilibrium metal-ion binding to isolated bovine fragment 1 and intact prothrombin. The close similarity of the rates obtained for the conformation change in fragment 1 and those observed in prothrombin indicated that the same process is involved in both proteins and that the non-fragment-1 region of the prothrombin has essentially no effect on this process in the fragment-1 region. Equilibrium metal-ion-binding studies indicate that the details of the metal-ion-binding process in fragment 1 and prothrombin are essentially the same. We conclude that the metal-ion-binding behaviour of the fragment-1 domain of intact prothrombin is identical with that of isolated fragment 1. PMID:6171251

  15. Neutron scattering determination of the binding of prothrombin to lipid vesicles

    SciTech Connect

    Torbet, J.

    1987-12-01

    Low-angle neutron scattering is used to study the binding of human prothrombin to small single-bilayer vesicles consisting of phosphatidylcholine and phosphatidylserine (1/1 w/w). The radius of gyration of prothrombin indicates that it is an elongated molecule. The vesicles alone were not observed to coalesce, and their molecular weight, outer radius, and average surface area per lipid were respectively (1.6 +/- 0.32) x 10/sup 6/, 114 +/- 4 A, and 110 +/- 18 A/sup 2/. These values were independent of the presence of calcium and were not altered significantly by prothrombin, which binds reversibly to the vesicle outer surface with its long axis projecting approximately radially forming a 90-A thick protein shell. From the titration of the protein-vesicle interaction, the apparent dissociation constant of the binding of prothrombin to these vesicles is estimated to be 0.8 +/- 0.4 ..mu..M. At saturation, 57 +/- 7 prothrombin molecules bind, giving 25 +/- 6 lipid residues and an area of 2900 +/- 400 A/sup 2/ per prothrombin molecule on the vesicle outer surface. This area is about twice that calculated from a prolate ellipsoid model for prothrombin. However, it is close to the maximum cross-sectional area of fragment 1, the lipid binding region of prothrombin, which is coin-shaped in the high-resolution X-ray structure. This similarity suggests that prothrombin binding could be sterically limited.

  16. Blood splash in lambs-a preliminary study using the one-stage prothrombin time test.

    PubMed

    Restall, D J

    1981-02-01

    Lambs from a flock in which a high incidence of blood splash had been detected were examined using the one-stage prothrombin test. For comparison lambs from a commercial slaughter line were also examined. All the affected lambs and 35·4% from the slaughter line had extended prothrombin times, and a relationship between extended prothrombin times and the occurrence of blood splash was established. Investigation of the pastures grazed by the affected flock showed the presence of coumarin producing plants and grasses. Some coumarin drugs prolong one-stage prothrombin times, and more importantly, induce capillary fragility, thus predisposing animals to blood splash.

  17. Effects of sugammadex on activated partial thromboplastin time and prothrombin time in healthy subjects.

    PubMed

    De Kam, Pieter-Jan; Grobara, Peter; Prohn, Marita; Höppener, Floris; Kluft, Cornelis; Burggraaf, Jacobus; Langdon, Ronald B; Peeters, Pierre

    2014-03-01

    To assess the impact of sugammadex on activated partial thromboplastin time (APTT) and international normalized ratio for prothrombin time (PT(INR)) in healthy subjects and characterize the concentration-dependency of sugammadex effects on APTT and prothrombin time (PT) in normal human plasma in vitro. Eight healthy subjects (18 - 45 years of age) were administered intravenous doses of 4 mg/kg sugammadex, 16 mg/kg sugammadex, or placebo in a randomized, placebo-controlled, three period cross-over trial. The primary endpoint was area under the curve from 2 to 60 minutes post-dose (AUC2-60min) for APTT and PT(INR). In vitro, the effects of sugammadex on APTT and PT were assessed in pooled normal human citrate plasma. In subjects dosed with 4 and 16 mg/kg sugammadex, geometric mean ratios (treated vs. placebo) for AUC2-60min were 1.085 (95% confidence interval, 0.888 - 1.325) and 1.019 (0.868 - 1.195), respectively, for APTT, and 1.047 (0.904 - 1.213) and 1.096 (0.953 - 1.261), respectively, for PT(INR). At individual timepoints, mean APTT and PT(INR) increased by up to 22% after 16 mg/kg sugammadex compared with placebo. All such increases occurred within 30 minutes post-dose. Sugammadex was generally well tolerated. In the in vitro experiments, addition of sugammadex to plasma resulted in limited, concentration dependent increases in both APTT and PT. At 200 μg/mL (the mean maximum concentration reached therapeutically), the relative increases were 29% and 19%, respectively. Administration of sugammadex is associated with a dose-related, limited and transient prolongation of APTT and PT(INR) that is unlikely to be of clinical relevance.

  18. Retraction: 'Number needed to treat with 4-factor prothrombin complex concentrate for urgent warfarin reversal' by Andrew Chua, Vishal Patel, Allison Perrin, Lee Stern, Jenifer Ehreth, Laurel Omert, Christopher Hood, Julie Farley, Michael McGlynn and Liping Huang.

    PubMed

    2017-04-01

    The above abstract from the THSNA 2016 Summit Abstract Proceedings, first published online in the American Journal of Hematology on 20 July 2016 in Wiley OnlineLibrary (www.onlinelibrary.wiley.com), and in Volume 91, Issue 9, p. E427, has been retracted by agreement between the authors, the journal Editor-in-Chief, Carlo Brugnara, and Wiley Periodicals, Inc. The retraction has been agreed due to concerns from the submitting authors that the abstract was inadvertently submitted prior to receiving approval from all authors and proper review of data analytics, thereby rendering it incomplete.

  19. Quantification of trace metals in water using complexation and filter concentration.

    PubMed

    Dolgin, Bella; Bulatov, Valery; Japarov, Julia; Elish, Eyal; Edri, Elad; Schechter, Israel

    2010-06-15

    Various metals undergo complexation with organic reagents, resulting in colored products. In practice, their molar absorptivities allow for quantification in the ppm range. However, a proper pre-concentration of the colored complex on paper filter lowers the quantification limit to the low ppb range. In this study, several pre-concentration techniques have been examined and compared: filtering the already complexed mixture, complexation on filter, and dipping of dye-covered filter in solution. The best quantification has been based on the ratio of filter reflectance at a certain wavelength to that at zero metal concentration. The studied complex formations (Ni ions with TAN and Cd ions with PAN) involve production of nanoparticle suspensions, which are associated with complicated kinetics. The kinetics of the complexation of Ni ions with TAN has been investigated and optimum timing could be found. Kinetic optimization in regard to some interferences has also been suggested.

  20. MASP-1 Induced Clotting--The First Model of Prothrombin Activation by MASP-1.

    PubMed

    Jenny, Lorenz; Dobó, József; Gál, Péter; Schroeder, Verena

    2015-01-01

    Mannan-binding lectin-associated serine protease-1 (MASP-1), a protein of the complement lectin pathway, resembles thrombin in terms of structural features and substrate specificity. Due to its interplay with several coagulation factors, it has the ability to induce fibrin clot formation independent of the usual coagulation activation pathways. We have recently shown that MASP-1 activates prothrombin and identified arginine (R) 155, R271, and R393 as potential cleavage sites. FXa cleaves R320 instead of R393, and thrombin cleaves R155 and R284 in prothrombin. Here we have used three arginine-to-glutamine mutants of prothrombin, R271Q, R320Q, R393Q and the serine-to-alanine active site mutant S525A to investigate in detail the mechanism of MASP-1 mediated prothrombin activation. Prothrombin wildtype and mutants were digested with MASP-1 and the cleavage products were analysed by SDS-PAGE and N-terminal sequencing. A functional clotting assay was performed by thrombelastography. We have found that MASP-1 activates prothrombin via two simultaneous pathways, either cleaving at R271 or R393 first. Both pathways result in the formation of several active alternative thrombin species. Functional studies confirmed that both R393 and R320 are required for prothrombin activation by MASP-1, whereas R155 is not considered to be an important cleavage site in this process. In conclusion, we have described for the first time a detailed model of prothrombin activation by MASP-1.

  1. MASP-1 Induced Clotting – The First Model of Prothrombin Activation by MASP-1

    PubMed Central

    Jenny, Lorenz; Dobó, József; Gál, Péter; Schroeder, Verena

    2015-01-01

    Mannan-binding lectin-associated serine protease-1 (MASP-1), a protein of the complement lectin pathway, resembles thrombin in terms of structural features and substrate specificity. Due to its interplay with several coagulation factors, it has the ability to induce fibrin clot formation independent of the usual coagulation activation pathways. We have recently shown that MASP-1 activates prothrombin and identified arginine (R) 155, R271, and R393 as potential cleavage sites. FXa cleaves R320 instead of R393, and thrombin cleaves R155 and R284 in prothrombin. Here we have used three arginine-to-glutamine mutants of prothrombin, R271Q, R320Q, R393Q and the serine-to-alanine active site mutant S525A to investigate in detail the mechanism of MASP-1 mediated prothrombin activation. Prothrombin wildtype and mutants were digested with MASP-1 and the cleavage products were analysed by SDS-PAGE and N-terminal sequencing. A functional clotting assay was performed by thrombelastography. We have found that MASP-1 activates prothrombin via two simultaneous pathways, either cleaving at R271 or R393 first. Both pathways result in the formation of several active alternative thrombin species. Functional studies confirmed that both R393 and R320 are required for prothrombin activation by MASP-1, whereas R155 is not considered to be an important cleavage site in this process. In conclusion, we have described for the first time a detailed model of prothrombin activation by MASP-1. PMID:26645987

  2. In vitro reversal of supratherapeutic rivaroxaban levels with coagulation factor concentrates.

    PubMed

    Körber, Mareike K; Langer, Elisabeth; Kaufner, Lutz; Sander, Michael; Von Heymann, Christian

    2016-09-01

    A bleeding patient undergoing therapy with new oral anticoagulants is every clinician's nightmare as no specific reversal agent is available yet. This in vitro study investigated the effect of prothrombin complex concentrate (PCC), recombinant activated factor VII (rFVIIa) and activated prothrombin complex concentrate (aPCC) on supratherapeutic rivaroxaban concentrations using standard laboratory parameters (prothrombin time [PT], activated partial thromboplastin time [aPTT] and PT ratio) and thromboelastometry (clotting time [CT]). Blood samples from 10 healthy volunteers were collected and spiked with a supratherapeutic dose of rivaroxaban. Afterwards PCC, rFVIIa and aPCC were added in two doses. The laboratory parameters were measured and thromboelastometry was performed. The addition of the reversal agents had the following statistically significant effects (all p<0.01): +25 IU/kg PCC: CT -15 s, aPTT +5 s; +50 IU/kg PCC: aPTT +11 s; +90 μg rFVIIa: CT -141 s; +25 IU/kg aPCC: CT -142 s, aPTT -9 s, PT ratio +14%, PT -10.5 s; +50 IU/kg aPCC: CT -118 s, aPTT -7 s, PT ratio +17%, PT -12.2 s. rFVIIa and aPCC, but not PCC, appear to shorten coagulation times significantly in standard laboratory and thromboelastometry assays. These results need confirmation through evaluation of these agents in the clinical setting.

  3. Test procedures and instructions for Hanford complexant concentrate supernatant cesium removal using CST

    SciTech Connect

    Hendrickson, D.W.

    1997-01-08

    This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test, using Hanford Complexant Concentrate supernatant liquor from tank 241-AN-107, in a bench-scale column. The cesium sorbent to be tested is crystalline silicotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-023, Hanford Complexant Concentrate Supernatant Cesium Removal Test Plan.

  4. Sensing of the concentration and enantiomeric excess of chiral compounds with tropos ligand derived metal complexes.

    PubMed

    Zhang, Peng; Wolf, Christian

    2013-08-11

    Palladium(II) complexes carrying chromophoric tropos ligands show a characteristic UV change and strong Cotton effects upon coordination of amino alcohols or diamines. The distinct (chir)optical responses can be used for instantaneous in situ determination of the concentration and ee of diamines and amino alcohols at low concentrations.

  5. Missense mutations in the gene encoding prothrombin corresponding to Arg596 cause antithrombin resistance and thrombomodulin resistance.

    PubMed

    Takagi, Yuki; Murata, Moe; Kozuka, Toshihiro; Nakata, Yukiko; Hasebe, Ryo; Tamura, Shogo; Takagi, Akira; Matsushita, Tadashi; Saito, Hidehiko; Kojima, Tetsuhito

    2016-11-30

    Antithrombin (AT) and thrombomodulin (TM) play important roles in the process of natural anticoagulation in vivo. Recently, we reported that the prothrombin Yukuhashi mutation (p.Arg596Leu) was associated with AT and TM resistance-related thrombophilia. To assess the AT and TM resistances associated with other missense mutations by single base substitution in the Arg596 codon, we generated recombinant variants (596Gln, 596Trp, 596Gly, and 596Pro) and investigated the effects on AT and TM anticoagulant functions. All variants except 596Pro were secreted in amounts comparable to that of the wild-type but exhibited variable procoagulant activities. After a 30-minute inactivation by AT, the relative residual activity of wild-type thrombin decreased to 15 ± 4.0 %, in contrast to values of all variants were maintained at above 80 %. The thrombin-AT complex formation, as determined by enzyme-linked immunosorbent assay, was reduced with all tested variants in the presence and absence of heparin. In the presence of soluble TM (sTM), the relative fibrinogen clotting activity of wild-type thrombin decreased to 16 ± 0.12 %, whereas that of tested variants was 37 %-56 %. In a surface plasmon resonance assay, missense Arg596 mutations reduced thrombin-TM affinity to an extent similar to the reduction of fibrinogen clotting inhibition. In the presence of sTM or cultured endothelial-like cells, APC generation was enhanced differently by variant thrombins in a thrombin-TM affinity-dependent manner. These data indicate that prothrombin Arg596 missense mutations lead to AT and TM resistance in the variant thrombins and suggest that prothrombin Arg596 is important for AT- and TM-mediated anticoagulation.

  6. Formation and stabilization of anionic metal complexes in concentrated aqueous quaternary ammonium salt solutions

    SciTech Connect

    Aronson, F.L.; Hwang, L.L.Y.; Ronca, N.; Solomon, N.A.; Steigman, J.

    1985-02-04

    Anionic complexes of transition metals were stabilized in aqueous solutions containing high concentrations of various short-chain quaternary ammonium salts. Compounds with longer paraffin chains were effective in much less concentrated solution. Complex ions were detected spectrophotometrically. FeCl/sub 4//sup -/, which is usually formed in concentrated HCl, was the predominant Fe(III) complex in 30 m choline chloride containing only 0.12 M HCl. A yellow transitory Tc(VII) chloro-addition intermediate, formed in the reduction of TcO/sub 4//sup -/ by concentrated HCl, was stabilized when the solution also contained 25 m choline chloride. Its spectrum, as well as the isolation of an already known Tc(VII) bipyridyl complex, is reported. Concentrated organic electrolytes also stabilized Tc(V) oxide halides against disproportionation and Tc(IV) hexahalides against hydrolysis. Halochromates of Cr(VI) were formed and stabilized in dilute acid containing quaternary ammonium salts. Their UV spectra showed the well-resolved vibronic fine structure associated with the symmetric chromium-to-oxygen charge-transfer band. It is known that these progressions are resolved in aprotic solvents, but not in aqueous acidic solution alone, and that the loss of fine structure in aqueous media is due to hydrogen bonding. The stabilization of anionic metal complexes and the resolution of vibronic structure in halochromates are probably consequences of water-structure-enforced ion paring. The present work suggests that the water molecules in immediate contact with the complex anions are more strongly hydrogen bonded to each other than to the complex. 21 references, 4 figures.

  7. In-line concentration measurement in complex liquids using ultrasonic sensors

    PubMed

    Henning; Daur; Prange; Dierks; Hauptmann

    2000-03-01

    Recently there has been increased demand for chemical sensors measuring in-line the concentration of selected substances in complex liquids in order to guarantee a high product quality in the process industry. At present there is a great interest in acoustic sensor systems for concentration measurements. This article presents a new ultrasonic sensor system consisting of a miniaturized multi-sensor arrangement for the comprehensive acoustic characterization of liquid mixtures. The sensor system measures sound velocity, impedance coefficient, attenuation coefficient and temperature.

  8. Effect of salt and surfactant concentration on the structure of polyacrylate gel/surfactant complexes.

    PubMed

    Nilsson, Peter; Unga, Johan; Hansson, Per

    2007-09-20

    Small-angle X-ray scattering was used to elucidate the structure of crosslinked polyacrylate gel/dodecyltrimethylammonium bromide complexes equilibrated in solutions of varying concentrations of surfactant and sodium bromide (NaBr). Samples were swollen with no ordering (micelle free), or they were collapsed with either several distinct peaks (cubic Pm3n) or one broad correlation peak (disordered micellar). The main factor determining the structure of the collapsed complexes was found to be the NaBr concentration, with the cubic structure existing up to approximately 150 mM NaBr and above which only the disordered micellar structure was found. Increasing the salt concentration decreases the polyion mediated attractive forces holding the micelles together causing swelling of the gel. At sufficiently high salt concentration the micelle-micelle distance in the gel becomes too large for the cubic structure to be retained, and it melts into a disordered micellar structure. As most samples were above the critical micelle concentration, the bulk of the surfactant was in the form of micelles in the solution and the surfactant concentration thereby had only a minor influence on the structure. However, in the region around 150 mM NaBr, increasing the surfactant concentration, at constant NaBr concentration, was found to change the structure from disordered micellar to ordered cubic and back to disordered again.

  9. X-ray absorption spectroscopy identifies calcium-uranyl-carbonate complexes at environmental concentrations.

    SciTech Connect

    Kelly, S. D.; Kemner, K. M.; Brooks, S. C.; Biosciences Division; ORNL

    2007-01-01

    Current research on bioremediation of uranium-contaminated groundwater focuses on supplying indigenous metal-reducing bacteria with the appropriate metabolic requirements to induce microbiological reduction of soluble uranium(VI) to poorly soluble uranium(IV). Recent studies of uranium(VI) bioreduction in the presence of environmentally relevant levels of calcium revealed limited and slowed uranium(VI) reduction and the formation of a Ca-UO{sub 2}-CO{sub 3} complex. However, the stoichiometry of the complex is poorly defined and may be complicated by the presence of a Na-UO{sub 2}-CO{sub 3} complex. Such a complex might exist even at high calcium concentrations, as some UO{sub 2}-CO{sub 3} complexes will still be present. The number of calcium and/or sodium atoms coordinated to a uranyl carbonate complex will determine the net charge of the complex. Such a change in aqueous speciation of uranium(VI) in calcareous groundwater may affect the fate and transport properties of uranium. In this paper, we present the results from X-ray absorption fine structure (XAFS) measurements of a series of solutions containing 50 {micro}M uranium(VI) and 30 mM sodium bicarbonate, with various calcium concentrations of 0-5 mM. Use of the data series reduces the uncertainty in the number of calcium atoms bound to the UO{sub 2}-CO{sub 3} complex to approximately 0.6 and enables spectroscopic identification of the Na-UO{sub 2}-CO{sub 3} complex. At nearly neutral pH values, the numbers of sodium and calcium atoms bound to the uranyl triscarbonate species are found to depend on the calcium concentration, as predicted by speciation calculations.

  10. X-ray Absorption Spectroscopy Identifies Calcium-Uranyl-Carbonate Complexes at Environmental Concentrations

    SciTech Connect

    Kelly, Shelly D; Kemner, Kenneth M; Brooks, Scott C

    2007-01-01

    Current research on bioremediation of uranium-contaminated groundwater focuses on supplying indigenous metal-reducing bacteria with the appropriate metabolic requirements to induce microbiological reduction of soluble uranium(VI) to poorly soluble uranium(IV). Recent studies of uranium(VI) bioreduction in the presence of environmentally relevant levels of calcium revealed limited and slowed uranium(VI) reduction and the formation of a Ca-UO2-CO3 complex. However, the stoichiometry of the complex is poorly defined and may be complicated by the presence of a Na-UO2-CO3 complex. Such a complex might exist even at high calcium concentrations, as some UO2-CO3 complexes will still be present. The number of calcium and/or sodium atoms coordinated to a uranyl carbonate complex will determine the net charge of the complex. Such a change in aqueous speciation of uranium(VI) in calcareous groundwater may affect the fate and transport properties of uranium. In this paper, we present the results from X-ray absorption fine structure (XAFS) measurements of a series of solutions containing 50 lM uranium(VI) and 30 mM sodium bicarbonate, with various calcium concentrations of 0-5 mM. Use of the data series reduces the uncertainty in the number of calcium atoms bound to the UO2-CO3 complex to approximately 0.6 and enables spectroscopic identification of the Na-UO2-CO3 complex. At nearly neutral pH values, the numbers of sodium and calcium atoms bound to the uranyl triscarbonate species are found to depend on the calcium concentration, as predicted by speciation calculations.

  11. [Evaluation of penicillin expandase mutants and complex substrate inhibition characteristics at high concentrations of penicillin G].

    PubMed

    Wu, Linjun; Fan, Keqiang; Ji, Junjie; Yang, Keqian

    2015-12-01

    Penicillin expandase, also known as deacetoxycephalosporin C synthase (DAOCS), is an essential enzyme involved in cephalosporin C biosynthesis. To evaluate the catalytic behaviors of penicillin expandase under high penicillin G concentration and to identify mutants suitable for industrial applications, the specific activities of wild-type DAOCS and several mutants with increased activities toward penicillin G were determined by HPLC under high penicillin G concentrations. Their specific activity profiles were compared with theoretical predictions by different catalytic dynamics models. We evaluated the specific activities of wild-type DAOCS and previous reported high-activity mutants H4, H5, H6 and H7 at concentrations ranging from 5.6 to 500 mmol/L penicillin G. The specific activities of wild-type DAOCS and mutant H4 increased as penicillin G concentration increased, but decreased when concentrations of substrate go above 200 mmol/L. Other mutants H5, H6 and H7 showed more complex behaviors under high concentration of penicillin G. Among all tested enzymes, mutant H6 showed the highest activity when concentration of penicillin G is above 100 mmol/L. Our results revealed that the substrate inhibition to wild-type DAOCS' by penicillin G is noncompetitive. Other DAOCS mutants showed more complex trends in their specific activities at high concentration of penicillin G (>100 mmol/L), indicating more complex substrate inhibition mechanism might exist. The substrate inhibition and activity of DAOCS mutants at high penicillin G concentration provide important insight to help select proper mutants for industrial application.

  12. Optimizing the Verification of Mean Normal Prothrombin Time (MNPT) and International Sensitivity Index (ISI) for Accurate Conversion of Prothrombin Time (PT) to International Normalized Ratio (INR).

    PubMed

    Favaloro, Emmanuel J

    2017-01-01

    The Prothrombin Time (PT) assay is the most common test performed in hemostasis laboratories, most commonly as converted to an international normalized ratio (INR) to monitor anticoagulant therapy using vitamin K antagonists (VKAs) such as warfarin. Although the INR is meant to standardize PT values by taking into consideration reagent and instrument variability, substantial inter-laboratory variation in INRs still exists and suggests that this can be further improved. This paper describes the PT test, its conversion to an INR value, and methods to improve the accuracy of INRs by improving the determination of critical components to the INR, namely the mean normal prothrombin time (MNPT) and the international sensitive index (ISI).

  13. Addition of prothrombin to plasma can result in a paradoxical increase in activated partial thromboplastin time.

    PubMed

    Hansson, Kenny M; Björkqvist, Jenny; Deinum, Johanna

    2014-12-01

    In the activated partial thromboplastin time (APTT) assay, a variety of nonphysiological reagents is used to induce contact activation. The sensitivity of the APTT response for different thrombin inhibitors has previously been found to be dependent on the used reagent. Recently, infusion of prothrombin (FII) has been used in in-vivo coagulopathy models and its effect has been analyzed in different assays. Therefore, we investigated whether the FII plasma concentration might affect APTT using different commercial reagents, applying both turbidimetry and viscometry. We compared both plasma-derived human FII (pd-hFII) and recombinant human FII (r-hFII). Similar results were found for pd-hFII and r-hFII with different APTT reagents. As expected, no effect on APTT was found by increasing the plasma concentration of FII using APTT reagents consisting of ellagic acid (Actin FS or Actin). Although with Pathromtin SL, consisting of SiO2, only a slight increase was found, with most other commercial APTT reagents, consisting of SiO2 or kaolin, APTT dose-dependently increased by increasing concentration of FII. Therefore, both Pathromtin SL and Actin FS were used to compare r-hFII and pd-hFII by determining the KM at 37C using FII-depleted plasma, providing values of 6 ± 0.3 nmol/l FII for both. Thus, at normal plasma concentrations of FII, the maximal initial thrombin generation rate should be reached and no effect on the coagulation time is expected at higher FII concentrations. To completely avoid the paradoxical effect in the APTT assay at FII concentrations higher than normal, Actin or Actin FS is the preferable reagent.

  14. Cotiarinase is a novel prothrombin activator from the venom of Bothrops cotiara.

    PubMed

    Kitano, Eduardo S; Garcia, Thalita C; Menezes, Milene C; Tashima, Alexandre K; Zelanis, André; Serrano, Solange M T

    2013-08-01

    Snake venom serine proteinases (SVSPs) may affect hemostatic pathways by specifically activating components involved in coagulation, fibrinolysis and platelet aggregation or by unspecific proteolytic degradation. In this study, we purified and characterized an SVSP from Bothrops cotiara venom, named cotiarinase, which generated thrombin upon incubation with prothrombin. Cotiarinase was isolated by a two-step procedure including gel-filtration and cation-exchange chromatographies and showed a single protein band with a molecular mass of 29 kDa by SDS-polyacrylamide gel electrophoresis under reducing conditions. Identification of cotiarinase by mass spectrometric analysis revealed peptides that matched sequences of viperid SVSPs. Cotiarinase did not show fibrinogen-clotting, platelet-aggregating, fibrinogenolytic and factor X activating activities. Upon incubation with prothrombin the generation of thrombin was detected using the peptide substrate d-Phe-Pip-Arg-pNA. Moreover, mass spectrometric identification of prothrombin fragments generated by cotiarinase in the absence of co-factors (phospholipids, factor Va, factor Xa and Ca(2+) ions), indicated the limited proteolysis of this protein to release prothrombin 1, fragment 1 and thrombin. Cotiarinase is a novel SVSP that acts on prothrombin to release active thrombin that does not match any group of the current classification of snake venom prothrombin activators.

  15. Group D prothrombin activators from snake venom are structural homologues of mammalian blood coagulation factor Xa.

    PubMed Central

    Rao, Veena S; Joseph, Jeremiah S; Kini, R Manjunatha

    2003-01-01

    Procoagulant venoms of several Australian elapids contain proteinases that specifically activate prothrombin; among these, Group D activators are functionally similar to coagulation factor Xa (FXa). Structural information on this class of prothrombin activators will contribute significantly towards understanding the mechanism of FXa-mediated prothrombin activation. Here we present the purification of Group D prothrombin activators from three Australian snake venoms (Hoplocephalus stephensi, Notechis scutatus scutatus and Notechis ater niger) using a single-step method, and their N-terminal sequences. The N-terminal sequence of the heavy chain of hopsarin D (H. stephensi) revealed that a fully conserved Cys-7 was substituted with a Ser residue. We therefore determined the complete amino acid sequence of hopsarin D. Hopsarin D shows approximately 70% similarity with FXa and approximately 98% similarity with trocarin D, a Group D prothrombin activator from Tropidechis carinatus. It possesses the characteristic Gla domain, two epidermal growth factor-like domains and a serine proteinase domain. All residues important for catalysis are conserved, as are most regions involved in interactions with factor Va and prothrombin. However, there are some structural differences. Unlike FXa, hopsarin D is glycosylated in both its chains: in light-chain residue 52 and heavy-chain residue 45. The glycosylation on the heavy chain is a large carbohydrate moiety adjacent to the active-site pocket. Overall, hopsarin D is structurally and functionally similar to mammalian coagulation FXa. PMID:12403650

  16. MASP-1 of the complement system promotes clotting via prothrombin activation.

    PubMed

    Jenny, Lorenz; Dobó, József; Gál, Péter; Schroeder, Verena

    2015-06-01

    Mannan-binding lectin-associated serine protease-1 (MASP-1), a protein of the complement lectin pathway, resembles thrombin in terms of structural features and substrate specificity, and it has been shown to activate coagulation factors. Here we studied the effects of MASP-1 on clot formation in whole blood (WB) and platelet-poor plasma (PPP) by thrombelastography and further elucidated the underlying mechanism. Cleavage of prothrombin by MASP-1 was investigated by SDS-PAGE and N-terminal sequencing of cleavage products. Addition of MASP-1 or thrombin to WB and PPP shortened the clotting time and clot formation time significantly compared to recalcified-only samples. The combination of MASP-1 and thrombin had additive effects. In a purified system, MASP-1 was able to induce clotting only in presence of prothrombin. Analysis of MASP-1-digested prothrombin confirmed that MASP-1 cleaves prothrombin at three cleavage sites. In conclusion, we have shown that MASP-1 is able to induce and promote clot formation measured in a global setting using the technique of thrombelastography. We further confirmed that MASP-1-induced clotting is dependent on prothrombin. Finally, we have demonstrated that MASP-1 cleaves prothrombin and identified its cleavage sites, suggesting that MASP-1 gives rise to an alternative active form of thrombin by cleaving at the cleavage site R393. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The Aqueous Thermodynamics and Complexation Reactions of Anionic Silica and Uranium Species to High Concentration

    SciTech Connect

    Felmy, Andrew R.

    2004-06-01

    Highly basic tank wastes contain several important radionuclides, including 90Sr, 99Tc, and 60Co, as well as actinide elements (i.e., isotopes of U, Pu, and Am). These highly basic tank wastes are known to have leaked into the vadose zone at the Hanford Site. Upon entering the sediments in the vadose zone, the highly basic solutions dissolve large concentrations of silica from the silica and aluminosilicate minerals present in the subsurface. These dissolution reactions alter the chemical composition of the leaking solutions, transforming them from a highly basic (as high 2M NaOH) solution into a pore solution with a very high concentration of dissolved silica and a significantly reduced pH. This moderately basic (pH 9 to 11), high-silica solution has the potential to complex radionuclides and move through the subsurface. Such strong radionuclide complexation is a currently unconsidered transport vector that has the potential to expedite radionuclide transport through the vad ose zone. These strong complexation effects have the ability to significantly alter current conceptual models of contaminant migration beneath leaking tanks. In this project, we are determining the aqueous thermodynamics and speciation of dissolved silica and silica-radionuclide complexes to high silica concentration. We are also initiating studies of U(VI) speciation under strongly basic conditions.

  18. Circulating microparticles in carriers of prothrombin G20210A mutation.

    PubMed

    Campello, E; Spiezia, L; Radu, C M; Gavasso, S; Zerbinati, P; Woodhams, B; Simioni, P

    2014-09-02

    Factor V Leiden (FVL) and prothrombin gene mutation G20210A (PTM) are the two most common genetic polymorphisms known to predispose carriers to venous thromboembolism (VTE). A recent study in FVL carriers showed that circulating levels of microparticles (MP) may contribute to their thrombogenic profile. To further elucidate the prothrombotic state linked to genetic thrombophilia, we extended this study to carriers of PTM. The plasma level of annexin V-MP, endothelial-MP (EMP), platelet-MP (PMP), tissue factor-bearing MP (TF+) and the MP procoagulant activity (PPL) was measured in 124 carriers of PTM (105 heterozygous and 19 homozygous) and in 120 age- and gender-matched healthy individuals. Heterozygous and homozygous carriers of PTM showed significantly increased levels of annexin V-MP (2930 [1440-4646] MP/µl and 3064 [2412-4906] MP/µl, respectively) and significantly shorter PPL clotting time (54 [46-67] sec and 55 [46-64] sec) compared to controls (1728 [782-2122] MP/µl and 71 [61-75] sec, respectively; p<0.01). Similarly, heterozygous and homozygous subjects presented with significantly higher levels of EMP, PMP and TF+ than controls (p<0.05). PTM carriers with a VTE history had significantly higher MP numbers and activity than controls. No significant difference was seen between carriers with and without a VTE history. We conclude that the higher levels of circulating MP found in PTM carriers may play a role in the development of VTE possibly by increasing thrombin generation. Further studies are needed to better define the role of MP as triggering factors for the thrombotic complications characterizing mild genetic thrombophilic defects.

  19. An Aqueous Thermodynamic Model for the Complexation of Nickel with EDTA Valid to high Base Concentration

    SciTech Connect

    Felmy, Andrew R.; Qafoku, Odeta

    2004-09-01

    An aqueous thermodynamic model is developed which accurately describes the effects of high base concentration on the complexation of Ni2+ by ethylenedinitrilotetraacetic acid (EDTA). The model is primarily developed from an extensive data on the solubility of Ni(OH)2(c) in the presence of EDTA and in the presence and absence of Ca2+ as the competing metal ion. The solubility data for Ni(OH)2(c) were obtained in solutions ranging in NaOH concentration from 0.01 to 11.6m, and in Ca 2+ concentrations extending to saturation with respect to portlandite, Ca(OH)2. Owing to the inert nature of the Ni-EDTA complexation reactions, solubility experiments were approached from both the oversaturation and undersaturation direction and over time frames extending to 413 days. The final aqueous thermodynamic model is based upon the equations of Pitzer, accurately predicts the observed solubilities to concentrations as high as 11.6m NaOH, and is consistent with UV-Vis spectroscopic studies of the complexes in solution.

  20. Thermodynamic modeling of neptunium(V)-acetate complexation in concentrated NaCl media

    SciTech Connect

    Novak, C.F.; Borkowski, M.; Choppin, G.R.

    1995-09-01

    The complexation of neptunium(V), Np(V), with the acetate anion, Ac{sup -}, was measured in sodium chloride media to high concentration using an extraction technique. The data were interpreted using the thermodynamic formalism of Pitzer, which is valid to high electrolyte concentrations. A consistent model for the deprotonation constants of acetic acid in NaCl and NaClO{sub 4} media was developed. For the concentrations of acetate expected in a waste repository, only the neutral complex NpO{sub 2}Ac(aq) was important in describing the interactions between the neptunyl ion and acetate. The thermodynamic stability constant log {beta}{sup 0}{sub 101} for the reaction NpO{sub 2}{sup +} + Ac{sup -} {leftrightarrow} NpO{sub 2}Ac was calculated to be 1.46{plus_minus}0.11. This weak complexing behavior between the neptunyl ion and acetate indicates that acetate will not significantly enhance dissolved Np(V) concentrations in ground waters associated with nuclear waste repositories that may contain acetate.

  1. Complexing sorbents with heterocyclic amino groups for concentrating platinum-group metals

    SciTech Connect

    Myasoedova, G.V.; Shcherbinina, N.I.; Komozin, P.N.

    1995-06-01

    Sorbents prepared on the basis of amines, in particular, those bearing heterocyclic amino groups and nitrogen-containing matrices, hold much promise for the sorptifve sepatration of platinum-group metals. The results of the study of new complexing sorbents based on 2,4,6-triamino-1,3,5-triazine (melamine) and bearing 3(5)-methylpyrazole, imidazole, and benzimidazole groups are presented in this work. The sorption and complexing properties of the sorbents with respect to platinum-group metals were studied. The possibility of using new sorbents for the group concentration of platinum-group metals was demonstrated.

  2. A method for systematic purification from bovine plasma of six vitamin K-dependent coagulation factors: prothrombin, factor X, factor IX, protein S, protein C, and protein Z.

    PubMed

    Hashimoto, N; Morita, T; Iwanaga, S

    1985-05-01

    A systematic purification scheme is presented for the isolation of six vitamin K-dependent coagulation factors from bovine plasma in a functionally and biochemically pure state. The vitamin K-dependent proteins concentrated by the ordinary barium citrate adsorption were first separated into four fractions, fractions A, B, C, and D, by DEAE-Sephadex A-50 chromatography. From the pooled fraction A, protein S, factor IX, and prothrombin were purified by column chromatography on Blue-Sepharose CL-6B. Heparin-Sepharose chromatography of the pooled fraction B provided mainly pure factor IX, in addition to homogeneous prothrombin. A high degree of resolution of protein C and prothrombin from the pooled fraction C was obtained with a Blue-Sepharose column. This dye-ligand chromatographic procedure was also very effective for the separation of protein Z and factor X contained in the pooled fraction D. Thus, these preparative procedures allowed high recovery of milligram and gram quantities of six vitamin K-dependent proteins from 15 liters of plasma in only two chromatographic steps, except for protein S, which required three (the third step was rechromatography on Blue-Sepharose CL-6B).

  3. Prevalence of prothrombin gene mutation (G-A 20210 A) in general population: a pilot study.

    PubMed

    Naeem, Muhammad Abdul; Anwar, Masood; Ali, Waqar; Ayyub, Muhammad; Nasiruddin, Nasiruddin

    2006-04-01

    The objective of this study was to determine the prevalence of prothrombin gene mutation in a sample population from Pakistan. Two hundred apparently healthy unrelated adults (older than 18 years) were included in the study. The sample population comprised 100 Punjabis (male 50, female 50) and 100 Pathans (male 50, female 50). Patients with a history of previous thromboembolism were excluded from the study. Five milliliters (5 mL) of whole blood was drawn in an EDTA bottle. The DNA was extracted by the standard phenol-chloroform method. The DNA was amplified between exon number 14 and the 3'-untranslated region of the prothrombin gene by a polymerase chain reaction in a thermal cycler. Amplified products were digested overnight with HindIII at 37 degrees C. The digested products were electrophoresed on 6% polyacrylamide gel. The fragments were visualized by silver nitrate staining. A heterozygous wild type and an uncut amplified product were included in the electrophoresis strip for quality control. The wild type of DNA ran as a 350-bp fragment and internal control was cut as 550- and 150-bp fragments. The abnormal prothrombin gene was cut into 350-, 322-, and 28-bp fragments. Only two cases of heterozygous prothrombin gene mutation G-A 20210A were found in the sample studied, giving an overall carrier rate of 01% (95% CI 0.4-2.4%) in the target population. Prothrombin gene mutation is present in our population but at a lower frequency than in the white population.

  4. Concentration measurements of complex mixtures of broadband absorbers by widely tunable optical parametric oscillator laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Ruxton, K.; Macleod, N. A.; Weidmann, D.; Malcolm, G. P. A.; Maker, G. T.

    2012-11-01

    The ability to obtain accurate vapour parameter information from a compound's absorption spectrum is an essential data processing application in order to quantify the presence of an absorber. Concentration measurements can be required for a variety of applications including environmental monitoring, pipeline leak detection, surface contamination and breath analysis. This work demonstrates sensitive concentration measurements of complex mixtures of volatile organic compounds (VOCs) using broadly tunable mid wave infrared (MWIR) laser spectroscopy. Due to the high absorption cross-sections, the MWIR spectral region is ideal to carry out sensitive concentration measurements of VOCs by tunable laser absorption spectroscopy (TLAS) methods. Absorption spectra of mixtures of VOCs were recorded using a MWIR optical parametric oscillator (OPO), with a tuning range covering 2.5 μm to 3.7 μm. The output of the MWIR OPO was coupled to a multi-pass astigmatic Herriott gas cell, maintained at atmospheric pressure that can provide up to 210 m of absorption path length, with the transmission output from the cell being monitored by a detector. The resulting spectra were processed by a concentration retrieval algorithm derived from the optimum estimation method, taking into account both multiple broadband absorbers and interfering molecules that exhibit narrow multi-line absorption features. In order to demonstrate the feasibility of the concentration measurements and assess the capability of the spectral processor, experiments were conducted on calibrated VOCs vapour mixtures flowing through the spectroscopic cell with concentrations ranging from parts per billion (ppb) to parts per million (ppm). This work represents as a first step in an effort to develop and apply a similar concentration fitting algorithm to hyperspectral images in order to provide concentration maps of the spatial distribution of multi-species vapours. The reported functionality of the novel fitting algorithm

  5. On the use of aptamer microarrays as a platform for the exploration of human prothrombin/thrombin conversion.

    PubMed

    Daniel, Camille; Roupioz, Yoann; Livache, Thierry; Buhot, Arnaud

    2015-03-15

    Microarrays are particular biosensors with multiple grafted probes that are generally used for parallel and simultaneous detection of various targets. In this study, we used microarrays with aptamer probes in order to follow up the different biomolecular interactions of a single enzyme, the thrombin protein, involved in the complex coagulation cascade. More precisely, thanks to label-free surface plasmon resonance imaging, we were able to monitor in real time an important step in the firing of the coagulation cascade in situ-the enzymatic transformation of prothrombin into thrombin, catalyzed by factor Xa. We were also able to appraise the influence of other biochemical factors and their corresponding inhibiting or enhancing behaviors on thrombin activation. Our study opens the door for the development of a complete microarray-based platform not only for the whole coagulation cascade analysis but also for novel drug screening assays in pharmacology. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Anti-phosphatidylserine/prothrombin antibodies: an additional diagnostic marker for APS?

    PubMed

    Pregnolato, Francesca; Chighizola, Cecilia B; Encabo, Susan; Shums, Zakera; Norman, Gary L; Tripodi, Armando; Chantarangkul, Veena; Bertero, Tiziana; De Micheli, Valeria; Borghi, Maria Orietta; Meroni, Pier Luigi

    2013-07-01

    Among the diagnostic assays for anti-phospholipid syndrome (APS), lupus anticoagulant (LA) is the strongest predictor of thrombosis; however, it presents several limitations as interference with anticoagulant therapy and poor inter-laboratory agreement. Two-thirds of LA activity is apparently due to antibodies against prothrombin (PT), usually detectable by ELISA. Binding of PT to phosphatidylserine (PS) has been shown to enhance solid-phase anti-PT assay sensitivity. To determine the prevalence of antibodies against PS/PT (aPS/PT) in APS, we tested the semiquantitative QUANTA Lite(®) aPS/PT ELISA in a cohort of 80 APS patients. The prevalence of aPS/PT was 81.3%, rising to 87.6% when considering LA-positive subjects only. We observed a strong correlation between aPS/PT and LA (p = 0.006). To note, APS patients with thrombotic manifestations displayed significantly higher IgG aPS/PT titers compared to 20 aPL asymptomatic carriers (p = 0.012). To rule out a possible cross-reactivity of anti-β2 glycoprotein I antibodies (aβ2GPI) with PS/PT complex, we tested two monoclonal aβ2GPI antibodies and an affinity-purified (AP) polyclonal aβ2GPI IgG obtained from the serum of a patient reacting against both β2GPI and PS/PT. The two monoclonal antibodies did not show any reactivity against PS/PT complex, similarly the AP IgGs did not react toward PS/PT antigen while preserved their aβ2GPI activity. Our findings suggest that aPS/PT are a definite antibody population in APS. Moreover, the good correlation between aPS/PT ELISA and LA may support its use as a surrogate test for LA, particularly useful to overcome the technical limitations of the functional assay.

  7. Interference of M-protein on prothrombin time test – case report

    PubMed Central

    Margetić, Sandra; Ćelap, Ivana; Dukić, Lora; Vukasović, Ines; Virović-Jukić, Lucija

    2016-01-01

    The aim of this report was to present a case of interference on prothrombin time (PT) test that directed further laboratory diagnostics and resulted with final detection of monoclonal gammopathy in an 88-year old man. Routine coagulation testing during medical examination at Emergency Department revealed unmeasurable PT (< 7% activity) and activated partial thromboplastin time (aPTT) within reference range. After repeated sampling for coagulation testing, PT was unmeasurable again, as well as fibrinogen level (< 0.8 g/L), thrombin time (TT) was significantly prolonged (107 seconds) and aPTT was within reference range. In both plasma samples refrigerated at 4 ˚C overnight, white gelatinous precipitate was visible between the cell and plasma layers and the presence of monoclonal protein (M-protein) was suggested in our patient. Further laboratory diagnostics revealed total serum proteins at concentration of 123 g/L and the presence of M-protein IgG lambda (λ) at concentration of 47.1 g/L. These results suggested monoclonal gammopathy as an underlying pathophysiological condition in our patient. Activities of coagulation factors II, V, VII and X were within reference ranges or increased. These results and correction of unmeasurable PT result to 67% in mixing test with commercial normal plasma suggest in vitro rather than in vivo interference of M-protein on PT result. In contrast, significantly prolonged TT results in all analysed samples suggest impact of M-protein on this global coagulation test due to possible effect on fibrin polymerization. PMID:27346971

  8. Gas-phase concentration, purification, and identification of whole proteins from complex mixtures.

    PubMed

    Reid, Gavin E; Shang, Hao; Hogan, Jason M; Lee, Gil U; McLuckey, Scott A

    2002-06-26

    Five proteins present in a relatively complex mixture derived from a whole cell lysate fraction of E. coli have been concentrated, purified, and dissociated in the gas phase, using a quadrupole ion trap mass spectrometer. Concentration of intact protein ions was effected using gas-phase ion/ion proton-transfer reactions in conjunction with mass-to-charge dependent ion "parking" to accumulate protein ions initially dispersed over a range of charge states into a single lower charge state. Sequential ion isolation events interspersed with additional ion parking ion/ion reaction periods were used to "charge-state purify" the protein ion of interest. Five of the most abundant protein components present in the mixture were subjected to this concentration/purification procedure and then dissociated by collisional activation of their intact multiply charged precursor ions. Four of the five proteins were subsequently identified by matching the uninterpreted product ion spectra against a partially annotated protein sequence database, coupled with a novel scoring scheme weighted for the relative abundances of the experimentally observed product ions and the frequency of fragmentations occurring at preferential cleavage sites. The identification of these proteins illustrates the potential of this "top-down" protein identification approach to reduce the reliance on condensed-phase chemistries and extensive separations for complex protein mixture analysis.

  9. A novel prothrombin time method to measure all non-vitamin K-dependent oral anticoagulants (NOACs).

    PubMed

    Lindahl, Tomas L; Arbring, Kerstin; Wallstedt, Maria; Rånby, Mats

    2017-09-11

    There is a clinical need for point-of-care (POC) methods for non-vitamin K-dependent oral anticoagulants (NOACs). We modified a routine POC procedure: Zafena's Simple Simon™ PT-INR, a room-temperature, wet-chemistry prothrombin time method of the Owren-type. To either increase or decrease NOAC interference, two assay variants were devised by replacing the standard 10 µL end-to-end capillary used to add the citrated plasma sample to 200 µL of prothrombin time (PT) reagent by either a 20 µL or a 5 µL capillary. All assay variants were calibrated to show correct PT results in plasma samples from healthy and warfarin-treated persons. For plasmas spiked with dabigatran, apixaban, or rivaroxaban, the 20 µL variant showed markedly higher PT results than the 5 µL. The effects were even more pronounced at room temperature than at +37 °C. In plasmas from patients treated with NOACs (n = 30 for each) there was a strong correlation between the PT results and the concentration of NOACs as determined by the central hospital laboratory. For the 20 µL variant the PT response of linear correlation coefficient averaged 0.90. The PT range was INR 1.1-2.1 for dabigatran and apixaban, and INR 1.1-5.0 for rivaroxaban. Using an INR ratio between the 20 µL and 5 µL variants (PTr20/5) made the NOAC assay more robust and independent of the patient sample INR value in the absence of NOAC. Detection limits were 80 µg/L for apixaban, 60 µg/L for dabigatran, and 20 µg/L for rivaroxaban. A wet-chemistry POC PT procedure was modified to measure the concentrations of three NOACs using a single reagent.

  10. [Effect of alclofenac on the prothrombin level in patients under treatment with anticoagulants].

    PubMed

    Kaufmann, E

    1977-06-25

    Simultaneous administration of the anticoagulants acenocoumarol, phenprocoumon or chlorindion and the antirheumatic substance alclofenac in long term trials has no observable influence on the prothrombin time of stabilized patients. When the anticoagulant (acenocoumarol or phenprocoumon) and the alclofenac therapy are begun simultaneously, a variation of the dose is necessary. Either a one-third lower initial dosage can be given, or, after attaining the maximal anticoagulation effect on the prothrombin time (48 h after beginning acenocoumarol therapy, 72 h with phenprocoumarol), a lower daily dosage must be administered once, in comparison to the other group without alclofenac therapy. The maintenace dosage is not influenced by alclofenac.

  11. Heritability of plasma concentrations of clotting factors and measures of a prethrombotic state in a protein C-deficient family.

    PubMed

    Vossen, C Y; Hasstedt, S J; Rosendaal, F R; Callas, P W; Bauer, K A; Broze, G J; Hoogendoorn, H; Long, G L; Scott, B T; Bovill, E G

    2004-02-01

    Earlier studies found strong support for a genetic basis for regulation of coagulation factor levels and measures of a prethrombotic state (d-dimer, prothrombin fragment 1.2). Estimation of how much of the variation in the levels of coagulation factors and measures of a prethrombotic state, including measures of protein C activation and inactivation, could be attributed to heritability and household effect. Blood samples were collected from 330 members of a large kindred of French-Canadian origin with type I protein C deficiency. Heritability and common household effect were estimated for plasma concentrations of prothrombin, factor (F)V, factor VIII, factor (F)IX, fibrinogen, von Willebrand factor (VWF), antithrombin, protein C, protein S, protein Z, protein Z-dependent protease inhibitor (ZPI), fibrinopeptide A (FPA), protein C activation peptide (PCP), activated protein C-protein C inhibitor complex (APC-PCI), activated protein C-alpha1-antitrypsin complex (APC-alpha1AT), prothrombin fragment 1.2 (F1.2) and d-dimer, using the variance component method in sequential oligo-genic linkage analysis routines (SOLAR). The highest heritability was found for measures of thrombin activity (PCP and FPA). High estimates were also found for prothrombin, FV, FIX, protein C, protein Z, ZPI, APC-PCI and APC-alpha1AT. An important influence of shared household effect on phenotypic variation was found for VWF, antithrombin, protein S and F1.2. We found strong evidence for the heritability of single coagulation factors and measures of a prethrombotic state. Hemostatic markers with statistically significant heritability constitute potential targets for the identification of novel genes involved in the control of quantitative trait loci.

  12. Variations in plasma motilin, somatostatin, and pancreatic polypeptide concentrations and the interdigestive myoelectric complex in dog.

    PubMed

    Poitras, P; Lemoyne, M; Tasse, D; Trudel, L; Yamada, T; Taylor, I L

    1985-12-01

    We have looked at the plasma concentrations of motilin, pancreatic polypeptide (PP), and somatostatin (STS) during the various phases of the interdigestive motor complex (IDMC) in dogs. As expected, motilin cyclical increase was always associated with the phase III of the IDMC. Statistical analysis of PP variations revealed a significant rise 10 min before duodenal phase III; however, in individual animals, this relationship was inconsistent. Although a dose-related increase in PP blood levels was induced by administration of synthetic canine motilin (0-200 ng kg-1 iv), fasting plasma levels of PP were not correlated with the concentrations of circulating endogenous motilin. After truncal vagotomy, while motilin release and the intestinal motility pattern remained unaltered, the phase III associated cyclical increases of PP disappeared. Infusion of physiological amounts of PP (1 microgram kg-1 h-1 for 3 h) mimicking the postprandial release failed to reproduce a fed pattern type of intestinal motility and of motilin secretion. No statistical correlation could be established between STS plasma levels and the motor activity of the intestine. STS plasma levels were not correlated with circulating concentrations of motilin and the exogenous administration of physiological doses of synthetic canine motilin failed to modify STS plasma levels. Morphine (200 micrograms kg-1 iv) stimulated only the release of motilin. These data suggest that the role played by circulating concentrations of PP and STS in the control of the IDMC in dog is at most minimal.

  13. nC60 deposition kinetics: the complex contribution of humic acid, ion concentration, and valence.

    PubMed

    McNew, Coy P; LeBoeuf, Eugene J

    2016-07-01

    The demonstrated toxicity coupled with inevitable environmental release of nC60 raise serious concerns about its environmental fate and transport, therefore it is crucial to understand how nC60 will interact with subsurface materials including attached phase soil and sediment organic matter (AP-SOM). This study investigated the attachment of nC60 onto a Harpeth humic acid (HHA) coated silica surface under various solution conditions using a quartz crystal microbalance with dissipation monitoring. The HHA coating greatly enhanced nC60 attachment at low ion concentrations while hindering attachment at high ion concentrations in the presence of both mono and divalent cations. At low ion concentrations, the HHA greatly reduced the surface potential of the silica, enhancing nC60 deposition through reduction in the electrostatic repulsion. At high ion concentrations however, the reduced surface potential became less important due to the near zero energy barrier to deposition and therefore non-DLVO forces dominated, induced by compaction of the HHA layer, and leading to hindered attachment. In this manner, observed contributions from the HHA layer were more complex than previously reported and by monitoring surface charge and calculated DLVO interaction energy alongside attachment experiments, this study advances the mechanistic understanding of the variable attachment contributions from the humic acid layer.

  14. [Adiponectin, insulin and glucose concentrations in overweight and obese subjects after a complex carbohydrates (fiber) diet].

    PubMed

    González Rodríguez, Dora Cristina; Solano R, Liseti; González Martínez, Julio César

    2009-09-01

    Adiponectin one of the cytokines secreted by the adipose tissue that regulates the energetic metabolism through glucose and insulin interactions, stimulates the oxidation of fatty acids, reduces the plasmatic triglycerides and improves glucose metabolism by increasing insulin sensibility. Serum concentrations of adiponectin, insulin and glucose were assessed in order to establish association to weight loss after a dietary regime based on consumption of complex carbohydrates (fiber) during six weeks. Overweight and obese subjects (n=56) were studied by anthropometry. Adiponectin and insulin were measured by ELISA and glucose by Colorimetry. Data was analyzed by non parametric tests to compare independent or related samples. 12 men and 44 women, aged 20 to 55 years, 17 overweight and 39 obese were assessed. Adiponectin concentration was significantly low at basal determination in all the subjects (4,47 +/- 1,64); being higher in women (4,62 +/- 1,57 vs 3,93 +/- 1,86 microU/mL in men), while glucose and insulin values were at normal range (82,46 +/-26,51 mg/dL and 14,12 +/- 10,15 microU/mL) respectively with no significant differences for sex. Overweight subjects had significantly higher adiponectin concentrations than obese participants, at all measurements. Dietary regime promoted significant increase in adiponectin concentration at second and sixth week, with a negative correlation to body mass index and gender as they lost body weight.

  15. Dental treatment for the patient on anticoagulant therapy: prothrombin time value--what difference does it make?

    PubMed

    Benoliel, R; Leviner, E; Katz, J; Tzukert, A

    1986-08-01

    Thirty patients taking anticoagulants received routine dental treatment without altering their prothrombin time values. In a follow-up of 5 years, no serious complications were seen in patients with a prothrombin time value of up to 2.5. A protocol is suggested for dental treatment in these patients.

  16. Global prevalence of prothrombin gene mutation G20210A and implications in women's health: a systematic review.

    PubMed

    Dziadosz, Margaret; Baxi, Laxmi V

    2016-07-01

    Distribution of hereditary thrombophilic gene mutations differs globally. Prothrombin gene mutation G20210A is a common prothrombotic single-nucleotide polymorphism. In this systematic review, we provide a comprehensive report of the prevalence of prothrombin G20210A across the globe. Databases [Pubmed, Web of Science, Embase] were interrogated from their inception through December 2015 for articles reporting prothrombin G20210A prevalence rates and ethnicity. Prevalence rates were organized by continent and ethnoracial ancestry. A total of 113 articles were included with a total 61 876 participants tested for prothrombin G20210A. Reported prevalence rates varied from 0 to 15.9% among ethnic groups, with higher rates seen in the thromboembolism affected cohort compared with the unaffected cohort. Carrier rate distribution is supported by known historical migration patterns of global populations. This review of prothrombin G20210A prevalence may guide resourceful screening for identification of hereditary thrombophilia in female populations of interest with hypercoagulable states.

  17. Effects of vanadium complexes supplementation on V, Cu, Mn, K, Fe, Zn, and Ca concentration in STZ diabetic rats pancreas.

    PubMed

    Krośniak, Mirosław; Kowalska, Joanna; Francik, Renata; Gryboś, Ryszard; Kwiatek, Wojciech M

    2014-01-01

    The objective of the study was to assess the effects of Na[V(V)O(O2)2(2,2'-bpy)] x 8 H2O (complex 1), Na[V(V)O(O2)2(1,10'-phen)] x 5 H2O (complex 2), Na[V(V)O(O2)2(4,4'-Me-2,2'-bpy)] x 8 H2O (complex 3), [V(V)O(SO,)(1,10'-phen)] x 2 H2O, (complex 4), [V(IV)O(SO4)(2,2'-bpy)] x H2O (complex 5), where: 2,2'-bpy = 2,2'-bipyridine, 1.10'-phen = 1,10'-phenanthroline, 4,4'-Me-2,2'-bpy = 4,4'-dimethyl-2,2'-bipyridine and a small insulin injection on V, Cu, Mn, K, Fe, Zn, and Ca concentration in the STZ (streptozotocin) diabetic rats pancreas during a 5-week treatment with the tested complexes. In all groups of animals metal concentration in the pancreas was investigated by means of Proton Induced X-ray Emission (PIXE) method. Maximum concentration of vanadium was observed in the pancreas for complex 5 (1.69 +/- 0.09 mg/kg dry weight), lower for complex 3 (1.51 +/- 0.10 mg/kg dry weight), and the lowest for complex 1 (1.21 +/- 0.27 mg/kg dry weight) supplementation. The influence of vanadium administration on other metals' concentration in the rats' pancreas was also investigated. All vanadium-tested complexes showed an increase of zinc concentration in the examined pancreas in comparison to the diabetic animals not treated with vanadium. The results were the highest for complex 1 and the lowest for complex 5. The concentration of Fe, Cu, Mn, K and Ca in the pancreas is not evidently influenced by administration of the vanadium complexes.

  18. Influence of the organic complex concentration on adsorption of herbicide in organic modified montmorillonite

    NASA Astrophysics Data System (ADS)

    Kaludjerovic, Lazar; Tomic, Zorica; Djurovic, Rada; Milosevic, Maja

    2016-04-01

    Pesticides are recognized as an important source of potential pollution to soil and water due to their mobility and degradation in soils. Results presented in this paper show impact of the organic complex concentration on the adsorption of herbicides (acetochlor) at the surface of the organic modified montmorillonite. In this work, natural montmorillonite from Bogovina, located near Boljevac municipality, was used for organic modification. Cation-exchange capacity of this montmorillonite was determined by extraction with ammonium acetate (86 mmol/100g of clay). Montmorillonite have been modified first with NaCl and than with two organic complexes, hexadecyltrimethylammonium bromide (HDTMA) and phenyltrimethylammonium chloride (PTMA). For both organic complexes, three saturation concentrations were selected for monitoring of the herbicide adsorption (43 mmol/100g of clay (0.5 CEC), 86 mmol/100g of clay (1 CEC) and 129 mmol/100g of clay (1.5 CEC)). Changes in the properties of the inorganic and organic bentonite have been examined using the X-ray powder diffraction (XRPD) and batch equilibrium method. Increase in basal spacing (d) of montmorillonites saturated with 1.5 CEC of organic cation indicate that sorption of PTMA and HDTMA can exceed the saturation of 1 CEC. Both organic montmorillonites have shown higher uptake of the herbicide, compared to the inorganic montmorillonite. Comparing the values Freundlich coefficients in batch equilibrium method, (presented in the form of log Kf and 1/n), it can be seen that the sorption decreases in the series: 0.5CEC> 1CEC> 1.5CEC> NaM, for both organic montmorillonites.

  19. Fermentation of high concentrations of maltose by Saccharomyces cerevisiae is limited by the COMPASS methylation complex.

    PubMed

    Houghton-Larsen, Jens; Brandt, Anders

    2006-11-01

    In Saccharomyces cerevisiae, genes encoding maltose permeases and maltases are located in the telomeric regions of different chromosomes. The COMPASS methylation complex, which methylates lysine 4 on histone H3, controls the silencing of telomeric regions. Yeast strains deleted for SWD1, SWD3, SDC1, SET1, BRE2, or SPP1, encoding components of the COMPASS complex, fermented a medium containing 22% maltose with noticeably higher attenuation than did the wild type, resulting in production of up to 29% more ethanol. The least effective strain was spp1. Absence of COMPASS components had no effect on the fermentation of media with 20% glucose, 20% sucrose, or 16% maltose. Deletion of SWD3 resulted in larger amounts of MAL12 transcript, encoding maltase, at the late stages of fermentation of 22% maltose. A similar effect on maltase activity and maltose uptake capability was seen. The lysine 4 residue of histone H3 was trimethylated in wild-type cells at the late stages, while only small amounts of the dimethylated form were detected. Trimethylation and dimethylation of this residue were not detected in strains deleted for SWD1, SWD3, SET1, BRE2, or SDC1. Trimethylated lysine 4 was apparent only at the early stages (48 and 96 h) of fermentation in an spp1 strain. This work indicates that the COMPASS complex represses the expression of maltose utilization genes during the late stages of fermentation of a high concentration of maltose.

  20. Relationship between residual feed intake and lymphocyte mitochondrial complex protein concentration and ratio in crossbred steers.

    PubMed

    Davis, M P; Brooks, M A; Kerley, M S

    2016-04-01

    Rate of oxygen uptake by muscle mitochondria and respiratory chain protein concentrations differed between high- and low-residual feed intake (RFI) animals. The hypothesis of this research was that complex I (CI), II (CII), and III (CIII) mitochondria protein concentrations in lymphocyte (blood) mitochondria were related to the RFI phenotype of beef steers. Daily feed intake (ADFI) was individually recorded for 92 Hereford-crossbreed steers over 63 d using GrowSafe individual feed intake system. Predicted ADFI was calculated as the regression of ADFI on ADG and midtest BW. Difference between ADFI and predicted ADFI was RFI. Lymphocytes were isolated from low-RFI (-1.32 ± 0.11 kg/d; = 10) and high-RFI (1.34 ± 0.18 kg/d; = 8) steers. Immunocapture of CI, CII, and CIII proteins from the lymphocyte was done using MitoProfile CI, CII, and CIII immunocapture kits (MitoSciences Inc., Eugene, OR). Protein concentrations of CI, CII, and CIII and total protein were quantified using bicinchoninic acid colorimetric procedures. Low-RFI steers consumed 30% less ( = 0.0004) feed and had a 40% improvement ( < 0.0001) in feed efficiency compared with high-RFI steers with similar growth ( = 0.78) and weight measurements ( > 0.65). High- and low-RFI steers did not differ in CI ( = 0.22), CII ( = 0.69), and CIII ( = 0.59) protein concentrations. The protein concentration ratios for CI to CII ( = 0.03) were 20% higher and the ratios of CI to CIII ( = 0.01) were 30% higher, but the ratios of CII to CIII ( = 0.89) did not differ when comparing low-RFI steers with high-RFI steers. The similar magnitude difference in feed intake, feed efficiency measurements, and CI-to-CIII ratio between RFI phenotypes provides a plausible explanation for differences between the phenotypes. We also concluded that mitochondria isolated from lymphocytes could be used to study respiratory chain differences among differing RFI phenotypes. Further research is needed to determine if lymphocyte mitochondrial

  1. Conversion of simulated radioactive pollutant gas concentrations for a complex building array into radiation dose.

    PubMed

    Gallacher, D J; Robins, A G; Hayden, P

    2016-12-01

    Methods used to convert wind tunnel and ADMS concentration field data for a complex building array into effective radiation dose were developed based on simulations of a site in central London. Pollutant source terms were from positron emitting gases released from a cyclotron and clinical PET radiotracer facility. Five years of meteorological data were analysed to determine the probability distribution of wind direction and speed. A hemispherical plume cloud model (both static and moving) was developed which enabled an expression of gamma-ray dose, taking into account build-up factors in air, in terms of analytic functions in this geometry. The standard building wake model is presented, but this is extended and developed in a new model to cover the concentration field in the vicinity of a roof top structure recirculation zone, which is then related to the concentration in the main building wake zone. For all models presented the effective dose was determined from inhalation, positron cloud immersion and gamma ray plume contributions. Results of applying these models for determination of radiation dose for a particular site are presented elsewhere.

  2. Association of Hospital Market Concentration With Costs of Complex Hepatopancreaticobiliary Surgery.

    PubMed

    Cerullo, Marcelo; Chen, Sophia Y; Dillhoff, Mary; Schmidt, Carl; Canner, Joseph K; Pawlik, Timothy M

    2017-09-20

    < .001) compared with moderately concentrated markets and 10.5% lower (95% CI, -16.2% to -4.4%; P = .001) compared with unconcentrated markets. Higher market concentration was associated with lower overall charges and lower costs of pancreatic and hepatic surgery. For complex, highly specialized procedures, hospital market consolidation may represent the best value proposition: better quality of care with lower costs.

  3. 21 CFR 864.7735 - Prothrombin-proconvertin test and thrombotest.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Prothrombin-proconvertin test and thrombotest. 864.7735 Section 864.7735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  4. Investigation of prothrombin time in human whole-blood samples with a quartz crystal biosensor.

    PubMed

    Müller, Lothar; Sinn, Stefan; Drechsel, Hartmut; Ziegler, Christiane; Wendel, Hans-Peter; Northoff, Hinnak; Gehring, Frank K

    2010-01-15

    Monitoring of blood coagulation and fibrinolysis is an important issue in treatment of patients with cardiovascular problems and in surgery when blood gets into contact with artificial surfaces. In this work a new method for measuring the coagulation time (prothrombin time, PT) of human whole-blood samples based on a quartz crystal microbalance (QCM) biosensor is presented. The 10 MHz sensors used in this work respond with a frequency shift to changes in viscosity during blood clot formation. For driving and for readout of the quartz, both a network analyzer and an oscillator circuit were utilized. The sensor surfaces were specifically coated with a thin polyethylene layer. We found that both frequency analysis methods are suitable to measure exact prothrombin times in a very good conformity with a mechanical coagulometer as a reference. The anticoagulant effect of heparin on the prothrombin time was exemplarily shown as well as the reverse effect of the heparin antagonist polybrene. The change of the viscoelastic properties during blood coagulation, reflected by the ratio of frequency and dissipation shifts, is discussed for different dilutions of the whole-blood samples. In conclusion, QCM is a distinguished biosensor technique to determine prothrombin time and to monitor heparin therapy in whole-blood samples. Due to the excellent potential of miniaturization and the availability of direct digital signals, the method is predestinated for incorporation and integration into other devices and is thus opening the field of application for inline coagulation diagnostic in extracorporeal blood circuits.

  5. 21 CFR 864.7735 - Prothrombin-proconvertin test and thrombotest.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Prothrombin-proconvertin test and thrombotest. 864.7735 Section 864.7735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864...

  6. 21 CFR 864.7735 - Prothrombin-proconvertin test and thrombotest.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Prothrombin-proconvertin test and thrombotest. 864.7735 Section 864.7735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864...

  7. 21 CFR 864.7735 - Prothrombin-proconvertin test and thrombotest.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Prothrombin-proconvertin test and thrombotest. 864.7735 Section 864.7735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864...

  8. 21 CFR 864.7735 - Prothrombin-proconvertin test and thrombotest.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Prothrombin-proconvertin test and thrombotest. 864.7735 Section 864.7735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864...

  9. Submitting Canine Blood for Prothrombin Time and Partial Thromboplastin Time Determinations

    PubMed Central

    Smalko, Donna; Johnstone, Ian B.; Crane, Stewart

    1985-01-01

    Practitioners commonly submit samples from dogs for partial thromboplastin time and prothrombin time determinations. Controversy exists as to the necessity for rapid separation of plasma and cells, and submission of the plasma on ice (or frozen). The purpose of this study was to address three questions. First, is it better to submit plasma or is whole blood satisfactory? Second, is it necessary to refrigerate the sample or is maintenance at room temperature (20° C) adequate? Third, does the sample have to arrive at the laboratory within a few hours of collection or can reliable partial thromboplastin time/prothrombin time determinations be made on samples up to 48 hours old? It has been shown by this study that reliable partial thromboplastin time and prothrombin time determinations can be carried out on canine plasma for up to 48 hours after collection regardless of whether or not the plasma is separated immediately; however the samples must be kept at 4°C. If the samples are maintained at room temperature, reliable prothrombin time determinations can be obtained for up to six hours after collection regardless of whether or not the plasma is separated immediately. Reliable partial thromboplastin time determinations can be made on plasma stored at 20°C for up to 24 hours after collection and possibly longer (up to 48 hours) if the plasma has been separated immediately. PMID:17422523

  10. Organic complexation and its control of the dissolved concentrations of copper and zinc in the Scheldt estuary

    NASA Astrophysics Data System (ADS)

    van den Berg, Constant M. G.; Merks, Adri G. A.; Duursma, Egbert K.

    1987-06-01

    Cathodic stripping voltammetry (CSV) is used to determine total (after UV-irradiation) and labile dissolved metal concentrations as well as complexing ligand concentrations in samples from the river Scheldt estuary. It was found that even at high added concentrations of catechol (1 m M for copper and 0·4 m M for iron) and of APDC (1 m M for zinc) only part of the dissolved metal was labile (5-58% for copper, 34-69% for zinc, 10-38% for iron); this discrepancy could be explained by the low solubility of iron which is largely present as colloidal material, and by competition for dissolved copper and zinc by organic complexing ligands. Ligand concentrations varied between 28 and 206 n M for copper and between 22 and 220 n M for zinc; part of the copper complexing ligands could be sub-divided into strong complexing sites with concentrations between 23 and 121 n M and weaker sites with concentrations between 44 and 131 n M. Values for conditional stability constants varied between (log K' values) 13·0 and 14·8 for strong and between 11·5 and 12·1 for weaker copper complexing ligands, whereas for zinc the values were between 8·6 and 10·6. The average products of ligand concentrations and conditional stability constants ( a-coefficients) were 6 × 10 2 for zinc and 6 × 10 6 for copper. The dissolved zinc concentration was found to co-vary with the zinc complexing ligand concentration throughout the estuary. It is argued that the zinc concentration is regulated, in this estuary at least, by interactions with dissolved organic complexing ligands. A similar relationship was apparent between the dissolved copper and the strong copper complexing ligand concentration. The total copper complexing ligand concentrations were much greater than the dissolved copper concentrations, suggesting that only strongly complexed copper is kept in solution. These results provide evidence for the first time that interactions of copper and zinc with dissolved organic complexing ligands

  11. In vitro reversal of supratherapeutic rivaroxaban levels with coagulation factor concentrates

    PubMed Central

    Körber, Mareike K.; Langer, Elisabeth; Kaufner, Lutz; Sander, Michael; von Heymann, Christian

    2016-01-01

    Background A bleeding patient undergoing therapy with new oral anticoagulants is every clinician’s nightmare as no specific reversal agent is available yet. This in vitro study investigated the effect of prothrombin complex concentrate (PCC), recombinant activated factor VII (rFVIIa) and activated prothrombin complex concentrate (aPCC) on supratherapeutic rivaroxaban concentrations using standard laboratory parameters (prothrombin time [PT], activated partial thromboplastin time [aPTT] and PT ratio) and thromboelastometry (clotting time [CT]). Materials and methods Blood samples from 10 healthy volunteers were collected and spiked with a supratherapeutic dose of rivaroxaban. Afterwards PCC, rFVIIa and aPCC were added in two doses. The laboratory parameters were measured and thromboelastometry was performed. Results The addition of the reversal agents had the following statistically significant effects (all p<0.01): +25 IU/kg PCC: CT −15 s, aPTT +5 s; +50 IU/kg PCC: aPTT +11 s; +90 μg rFVIIa: CT −141 s; +25 IU/kg aPCC: CT −142 s, aPTT −9 s, PT ratio +14%, PT −10.5 s; +50 IU/kg aPCC: CT −118 s, aPTT −7 s, PT ratio +17%, PT −12.2 s. Discussion rFVIIa and aPCC, but not PCC, appear to shorten coagulation times significantly in standard laboratory and thromboelastometry assays. These results need confirmation through evaluation of these agents in the clinical setting. PMID:27177413

  12. Calculation of 2,3,7,8-TCDD equivalent concentrations of complex environmental contaminant mixtures

    PubMed Central

    Eadon, George; Kaminsky, Laurence; Silkworth, Jay; Aldous, Kenneth; Hilker, David; O'Keefe, Patrick; Smith, Robert; Gierthy, John; Hawley, John; Kim, Nancy; DeCaprio, Anthony

    1986-01-01

    Sufficient toxicological data are now available to permit use of conventional risk assessment techniques to estimate the hazards associated with human exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). However, many real-world exposures involve complex mixtures of dibenzodioxins, dibenzofurans, and related compounds. Historical approaches to risk assessment on such mixtures have ranged from ignoring all compounds except 2,3,7,8-TCDD itself to assuming that all compounds have potencies equal to 2,3,7,8-TCDD. An alternative approach which uses existing literature data and analytical results to calculate the “2,3,7,8-TCDD equivalent” concentration of a mixture in order to “predict” its biological potency relative to 2,3,7,8-TCDD itself is advanced here. Previously reported in vivo acute and subchronic studies and some recently obtained analytical chemistry data are integrated here to clarify the utility of this important approach and to assess the uncertainties associated with its use. This predictive approach, and various conceptually similar ones, have now found wide applicability to the risk assessment process associated with exposure to complex mixtures of dioxins, dibenzofurans, and related compounds. PMID:3830107

  13. Activation of the SK potassium channel-calmodulin complex by nanomolar concentrations of terbium

    PubMed Central

    Li, Weiyan; Aldrich, Richard W.

    2009-01-01

    Small conductance Ca2+-activated K+ (SK) channels sense intracellular Ca2+ concentrations via the associated Ca2+-binding protein calmodulin. Structural and functional studies have revealed essential properties of the interaction between calmodulin and SK channels. However, it is not fully understood how the binding of Ca2+ to calmodulin leads to channel opening. Drawing on previous biochemical studies of free calmodulin using lanthanide ions as Ca2+ substitutes, we have used the lanthanide ion, Tb3+, as an alternative ligand to study the activation properties of SK channels. We found that SK channels can be fully activated by nanomolar concentrations of Tb3+, indicating an apparent affinity >100-fold higher than Ca2+. Competition experiments show that Tb3+ binds to the same sites as Ca2+ to activate the channels. Additionally, SK channels activated by Tb3+ demonstrate a remarkably slow deactivation process. Comparison of our results with previous biochemical studies suggests that in the intact SK channel complex, the N-lobe of calmodulin provides ligand-binding sites for channel gating, and that its ligand-binding properties are comparable to those of the N-lobe in isolated calmodulin. PMID:19144926

  14. Reduction of arsenic content in a complex galena concentrate by Acidithiobacillus ferrooxidans.

    PubMed

    Makita, Mario; Esperón, Margarita; Pereyra, Benito; López, Alejandro; Orrantia, Erasmo

    2004-10-13

    Bioleaching is a process that has been used in the past in mineral pretreatment of refractory sulfides, mainly in the gold, copper and uranium benefit. This technology has been proved to be cheaper, more efficient and environmentally friendly than roasting and high pressure moisture heating processes. So far the most studied microorganism in bioleaching is Acidithiobacillus ferrooxidans. There are a few studies about the benefit of metals of low value through bioleaching. From all of these, there are almost no studies dealing with complex minerals containing arsenopyrite (FeAsS). Reduction and/or elimination of arsenic in these ores increase their value and allows the exploitation of a vast variety of minerals that today are being underexploited. Arsenopyrite was totally oxidized. The sum of arsenic remaining in solution and removed by sampling represents from 22 to 33% in weight (yield) of the original content in the mineral. The rest of the biooxidized arsenic form amorphous compounds that precipitate. Galena (PbS) was totally oxidized too, anglesite (PbSO4) formed is virtually insoluble and remains in the solids. The influence of seven factors in a batch process was studied. The maximum rate of arsenic dissolution in the concentrate was found using the following levels of factors: small surface area of particle exposure, low pulp density, injecting air and adding 9 K medium to the system. It was also found that ferric chloride and carbon dioxide decreased the arsenic dissolution rate. Bioleaching kinetic data of arsenic solubilization were used to estimate the dilution rate for a continuous culture. Calculated dilution rates were relatively small (0.088-0.103 day(-1)). Proper conditions of solubilization of arsenic during bioleaching are key features to improve the percentage (22 to 33% in weight) of arsenic removal. Further studies are needed to determine other factors that influence specifically the solubilization of arsenic in the bioleaching system such as

  15. Reduction of arsenic content in a complex galena concentrate by Acidithiobacillus ferrooxidans

    PubMed Central

    Makita, Mario; Esperón, Margarita; Pereyra, Benito; López, Alejandro; Orrantia, Erasmo

    2004-01-01

    Background Bioleaching is a process that has been used in the past in mineral pretreatment of refractory sulfides, mainly in the gold, copper and uranium benefit. This technology has been proved to be cheaper, more efficient and environmentally friendly than roasting and high pressure moisture heating processes. So far the most studied microorganism in bioleaching is Acidithiobacillus ferrooxidans. There are a few studies about the benefit of metals of low value through bioleaching. From all of these, there are almost no studies dealing with complex minerals containing arsenopyrite (FeAsS). Reduction and/or elimination of arsenic in these ores increase their value and allows the exploitation of a vast variety of minerals that today are being underexploited. Results Arsenopyrite was totally oxidized. The sum of arsenic remaining in solution and removed by sampling represents from 22 to 33% in weight (yield) of the original content in the mineral. The rest of the biooxidized arsenic form amorphous compounds that precipitate. Galena (PbS) was totally oxidized too, anglesite (PbSO4) formed is virtually insoluble and remains in the solids. The influence of seven factors in a batch process was studied. The maximum rate of arsenic dissolution in the concentrate was found using the following levels of factors: small surface area of particle exposure, low pulp density, injecting air and adding 9 K medium to the system. It was also found that ferric chloride and carbon dioxide decreased the arsenic dissolution rate. Bioleaching kinetic data of arsenic solubilization were used to estimate the dilution rate for a continuous culture. Calculated dilution rates were relatively small (0.088–0.103 day-1). Conclusion Proper conditions of solubilization of arsenic during bioleaching are key features to improve the percentage (22 to 33% in weight) of arsenic removal. Further studies are needed to determine other factors that influence specifically the solubilization of arsenic in

  16. Association Between the G20210A Polymorphism of Prothrombin Gene and Myocardial Infarction in Tunisian Population.

    PubMed

    Kallel, Amani; Sbaï, Mohamed Hedi; Sédiri, Yousra; Feki, Moncef; Mourali, Mohamed Sami; Mechmeche, Rachid; Jemaa, Riadh; Kaabachi, Naziha

    2016-10-01

    The prothrombin is the precursor of the serine protease thrombin, a key enzyme in homeostasis. Prothrombin G20210A polymorphism (rs1799963) was described as a moderate risk factor for venous thrombosis because this mutation is associated with prothrombin elevated levels which may lead to an imbalance between the procoagulant, anticoagulant, and fibrinolytic system. 20210A carriers have an increased risk of thrombosis. In this study, we proposed to determine the prevalence of 20210A prothrombin variant among Tunisian population, and to evaluate the potential relevance of this variant with myocardial infarction. This study included 1290 unrelated Tunisians (1007 male and 283 female) divided in two groups: Four hundred and eighty-seven MI patients (mean age: 52.64 ± 8.98 years) and 803 apparently healthy controls (mean age: 51 ± 8.99). The prothrombin G20210A polymorphism was carried out by polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP) analysis. The distribution of genotypes was in accordance with Hardy-Weinberg equilibrium (p > 0.05). A significant difference in genotype distribution and allele frequency was observed between patients and controls. Male patients with MI had a frequency of 97 % for GG genotype and 3 % for GA+AA genotypes. The control group had a frequency of 99 % for the GG genotype and 1 % for the GA+AA genotypes which is significantly lower than the frequency found in patients (p = 0.01). The same genotype frequencies were found in women (p = 0.032). The MI patient group showed a significantly higher frequency of 20210A allele compared to controls 0.02 versus 0.01 [OR = 3.60 (95 % CI = 1.29-10.53), p = 0.005] in men and 0.015 versus 0.068 [OR = 4.68 (95 % CI = 1.60-14.26), p = 0.001] in women. Our work showed a significant but not independent association between the G20210A polymorphism of the prothrombin gene and MI in the Tunisian population.

  17. Ground-based microwave complex for remote sounding of middle atmosphere thermal structure and ozone concentration

    NASA Astrophysics Data System (ADS)

    Shvetsov, Alexander; Kulikov, Mikhail; Feigin, Alexander; Karashtin, Dmitry; Krasilnikov, Alexander; Mukhin, Dmitry; Bolshakov, Oleg; Fedoseev, Lev; Ryskin, Vitaly; Belikovich, Michael; Kukin, Lev

    2012-07-01

    Existing methods of remote sensing of the thermal structure of the atmosphere and the ozone layer are based on measurements from space. However, having great advantage in global coverage of the Earth they cannot provide high spatial and temporal resolution, required to study rapidly occurring phenomena. This problem can be solving by ground-based system of remote sounding. For this purpose ground-based microwave complex for remote sensing of middle atmosphere thermal structure and ozone concentration have been developed in the Institute of Applied Physics of the Russian Academy of Sciences. The complex consists of the microwave ozonometer and the stratospheric thermometer. Ozonometer is a heterodyne spectroradiometer, operating in the frequency range that include the rotation transition of ozone molecules 6 _{1.5}-6 _{0.6} with resonance frequency 110.836 GHz. Operating frequency range of the stratospheric thermometer is 52.5-54.5 GHz and includes low frequency edge of 5 mm molecular oxygen absorption bands and some relatively weak lines of O _{2} resolved from the ground. Digital fast Fourier transform spectrometer developed by ``Acqiris'' company is employed for signal spectral analysis on intermediate frequency in both spectroradiometers. The spectrometer has frequency range 0.05-1 GHz and realizes the effective resolution about 61~KHz. Retrieval of the atmospheric temperature and ozone profiles is made on the basis of results of the radiation spectrum measurements. The Bayesian approach method is used for combined retrieval of stratosphere temperature and ozone profiles. This method allows statistically correct inclusion of both the measurement noise and the a priori information on the reconstructed profile needed for regularization of the problem. First simultaneous ground-based measurements of self-radiation of atmospheric ozone and oxygen have been made in January, 2012 during the sudden stratospheric warming above Nizhny Novgorod, Russia. Temperature and

  18. The Aqueous Thermodynamics and Complexation Reactions of Anionic Silica and Uranium Species to High Concentration.

    SciTech Connect

    Felmy, Andrew R.; Choppin, Gregory R.

    2005-06-01

    Highly basic tank wastes contain several important radionuclides, including 90Sr, 99Tc, and 60Co, as well as actinide elements (i.e., isotopes of U, Pu, and Am). These highly basic tank wastes are known to have leaked into the vadose zone at the Hanford Site. In particular, wastes from the bismuth phosphate process contained very high concentrations of U as well as carbonate, phosphate, nitrate, and other components (AEC 1951) and these solutions have leaked into the subsurface at the Hanford site. The tanks containing the bismuth phosphate wastes were frequently saturated with respect to the solid phases of these components [e.g., NaUO2PO4(c) and Na4UO2(CO3)3(c)]. These solids were referred to as ''hard sludge'' (Na4UO2(CO3)3(c)) and ?soft sludge? [NaUO2PO4(c)] because of their different crystal forms. The preliminary studies of the solubility of these solids in tank wastes (AEC 1951) indicate that aqueous U carbonate complexes dominate the solution chemistry of uranium even when the equilibrium solid was NaUO2PO4. Thus there was a need to develop an accurate thermodynamic model for the solubility of potentially important U(VI) phosphate and carbonate phases as well as to develop a model for the uranium carbonate complexes valid to high ionic strength. In this project we are examining the solubility of these important solid phases as well as the aqueous thermodynamics of U(VI) species under strongly basic conditions. Also included is a description of our efforts to include these thermodynamic models in the reactive transport and residual leaching models being used at the Hanford site and elsewhere.

  19. An unusual cause of cerebral venous sinus thrombosis: prothrombin G20210A gene mutation.

    PubMed

    Porres-Aguilar, Mateo; Square, Jaime H; Storey, Raul; Rodriguez-Dunn, Simon; Mohamed-Aly, Mohamed S

    2007-09-01

    Cerebral venous sinus thrombosis represents less than 1% of all strokes, being an uncommon entity with a wide spectrum of clinical scenarios. We present a 45-year-old Hispanic female with a history of long-term oral contraceptive use who was diagnosed with cerebral venous sinus thrombosis due to a heterozygous carrier mutation in the prothrombin G20210A gene. The patient was successfully managed with intravenous heparin with favorable clinical results without adverse effects. The prevalence of inherited primary thrombophilia increases with additional risk factors such as the use of oral contraceptives that can trigger or prothrombotic events in any vascular bed. An increased prevalence in the prothrombin G20210 gene mutation has been demonstrated in the Mexican-Mestizo population. Controversy exists regarding therapy of cerebral venous sinus thrombosis; according to experts, heparin remains the cornerstone of therapy with acceptable outcomes. More clinical trials are required to evaluate long-term outcomes in this subgroup of patients.

  20. Activation of prothrombin by two subtilisin-like serine proteases from Acremonium sp.

    PubMed

    Liu, Chunli; Matsushita, Yasuhiko; Shimizu, Kosuke; Makimura, Koichi; Hasumi, Keiji

    2007-06-22

    Two novel subtilisin-like serine proteases (AS-E1 and -E2) that activate prothrombin have been identified in a culture of the fungus Acremonium sp. The enzymes were purified through repeated hydrophobic interaction chromatography. The N-terminal sequences of AS-E1 (34.4 kDa) and AS-E2 (32 kDa) showed high similarity to the internal sequences of two distinct subtilisin-like hypothetical proteins from Chaetomium globosum. Both enzymes proteolytically activated prothrombin to meizothrombin(desF1)-like molecules, while the activation cleavage seemed to occur at a site (Tyr(316)-Ile(317)) that is four residues proximal to the canonical Xa cleavage site (Arg(320)-Ile(321)). Both enzymes inhibited plasma clotting, possibly due to extensive degradation of fibrinogen and production of meizothrombin(desF1)-like molecule.

  1. THE FACTORS OF COAGULATION IN THE EXPERIMENTAL APLASTIC ANEMIA OF BENZOL POISONING, WITH SPECIAL REFERENCE TO THE ORIGIN OF PROTHROMBIN

    PubMed Central

    Hurwitz, S. H.; Drinker, C. K.

    1915-01-01

    1. Subcutaneous injections of benzol in rabbits produce marked destructive changes in the hematopoietic organs, especially in the myeloid tissue. 2. Benzol poisoning registers a change not only in the formed elements of the blood, but also in the factors of coagulation. 3. The circulating prothrombin is considerably reduced in amount and in most instances animals in which such a diminution occurs show aplasia of the bone marrow. 4. The association of extreme aplasia of the marrow without a fatal diminution in the circulating prothrombin suggests one of two possibilities: either other tissues and organs in addition to the bone marrow are concerned with prothrombin formation; or a minimum amount of myeloid tissue suffices to maintain the quantity of prothrombin above a dangerous level. PMID:19867880

  2. Prothrombin G20210A and methylenetetrahydrofolate reductase C677T polymorphisms in peripheral capillary nonperfusion: a case report.

    PubMed

    Wathek, Chaima; Mrad, Meriem; Abdessalem, Nadia Ben; Maalej, Afef; Gritli, Nasreddine; Gabsi, Salem; Rannen, Riadh; Fekih-Mrissa, Najiba

    2015-09-01

    The G20210A mutation in the prothrombin gene is an established risk factor for venous thrombosis. However, there is some controversy as to the role played by this mutation in arterial thrombotic disease. The association of peripheral capillary nonperfusion with prothrombin G20210A mutation has never been reported before. We present the case of 34-year-old man who presented with peripheral capillary nonperfusion. The fundus examination of his right eye revealed an epiretinal membrane, peripheral (mainly temporally) retinal haemorrhages, exudates and microaneurismal alterations of the vascular bed. Fluorescein angiography of his right eye demonstrated an extended area of capillary nonperfusion distal to the microaneurismal lesions. Evaluation revealed mutations of the G20210A prothrombin and MTHFR genes. Screening for hereditary thrombophilia should be considered, regardless of patient age, in patients with peripheral retinal ischemia. The prothrombin G20210A mutation, a genetic risk factor, may be associated with peripheral capillary nonperfusion.

  3. A fluorescence anisotropy method for measuring protein concentration in complex cell culture media.

    PubMed

    Groza, Radu Constantin; Calvet, Amandine; Ryder, Alan G

    2014-04-22

    The rapid, quantitative analysis of the complex cell culture media used in biopharmaceutical manufacturing is of critical importance. Requirements for cell culture media composition profiling, or changes in specific analyte concentrations (e.g. amino acids in the media or product protein in the bioprocess broth) often necessitate the use of complicated analytical methods and extensive sample handling. Rapid spectroscopic methods like multi-dimensional fluorescence (MDF) spectroscopy have been successfully applied for the routine determination of compositional changes in cell culture media and bioprocess broths. Quantifying macromolecules in cell culture media is a specific challenge as there is a need to implement measurements rapidly on the prepared media. However, the use of standard fluorescence spectroscopy is complicated by the emission overlap from many media components. Here, we demonstrate how combining anisotropy measurements with standard total synchronous fluorescence spectroscopy (TSFS) provides a rapid, accurate quantitation method for cell culture media. Anisotropy provides emission resolution between large and small fluorophores while TSFS provides a robust measurement space. Model cell culture media was prepared using yeastolate (2.5 mg mL(-1)) spiked with bovine serum albumin (0 to 5 mg mL(-1)). Using this method, protein emission is clearly discriminated from background yeastolate emission, allowing for accurate bovine serum albumin (BSA) quantification over a 0.1 to 4.0 mg mL(-1) range with a limit of detection (LOD) of 13.8 μg mL(-1). Copyright © 2014. Published by Elsevier B.V.

  4. Disruption of Prostate Microvasculature by Combining Microbubble-Enhanced Ultrasound and Prothrombin

    PubMed Central

    Liu, Yongliang; Qiao, Lu; Gao, Wenhong; Zhang, Weiguo; Liu, Zheng

    2016-01-01

    Previous studies have shown a unique method to disrupt tumor vasculature using pulsed, high-pressure amplitude therapeutic ultrasound combined with microbubbles. In this study, we attempted to destroy the prostate vasculature of canine prostates using microbubble-enhanced ultrasound (MEUS) and prothrombin. The prostates of 43 male mongrel canines were surgically exposed. Twenty-two prostates were treated using MEUS (n = 11) or MEUS and prothrombin (PMEUS, n = 11). The other 21 prostates, which were treated using microbubbles (n = 7), ultrasound (n = 7) or prothrombin (n = 7) only, served as the controls. Prothrombin was intravenously infused at 20 IU/kg. MEUS was induced using a therapeutic ultrasound device at a peak negative pressure of 4.47 MPa and a microbubble injection. Contrast-enhanced ultrasound was performed to assess the blood perfusion of the prostates. Then, the prostate tissue was harvested immediately after treatment and at 48 hours later for pathological examination. The contrast-enhanced ultrasound peak value of the prostate decreased significantly from 36.2 ± 5.6 to 27.1 ± 6.3 after treatment in the PMEUS group, but it remained unchanged in the other groups. Histological examination found severe microvascular rupture, hemorrhage and thrombosis in both MEUS- and PMEUS-treated prostates immediately after treatment, while disruption in the PMEUS group was more severe than in the MEUS group. Forty-eight hours after treatment, massive necrosis and infiltration of white blood cells occurred in the PMEUS group. This study demonstrated that PMEUS disrupted the normal microvasculature of canine prostates and induced massive necrosis. PMEUS could potentially become a new noninvasive method used for the treatment of benign prostatic hyperplasia. PMID:27643992

  5. Disparate temporal expression of the prothrombin and thrombin receptor genes during mouse development.

    PubMed Central

    Soifer, S. J.; Peters, K. G.; O'Keefe, J.; Coughlin, S. R.

    1994-01-01

    The protease thrombin is a potent agonist for platelet aggregation, mesenchymal cell proliferation, and endothelial production of growth factors and adhesion molecules. Thrombin also modulates neurite outgrowth in neuronal cultures. These apparently disparate responses to thrombin appear to be largely mediated by the recently cloned thrombin receptor. In the adult, thrombin is generated from its zymogen prothrombin at sites of vascular injury when circulating coagulation factors meet extravascular tissue factor. In this context thrombin's varied actions may mediate responses to wounding. Whether thrombin's actions on cells may also play a role in development is unknown. We examined the expression of thrombin receptor, prothrombin, and tissue factor by in situ hybridization in mouse development. Thrombin receptor mRNA was expressed widely in mesenchymal cell populations during early organogenesis (E9.5) and was particularly abundant in developing heart and blood vessels. Robust receptor expression was also noted in the germinal epithelium of the hindbrain. Thrombin receptor expression became more restricted with time and by the fetal growth stage (E16.5) was most readily detected in certain neurons, endocardial and endothelial cells, and within lung and liver. In contrast to the thrombin receptor, prothrombin mRNA was limited to the embryonic liver and was not detected until E12.5, well after the onset of receptor expression. mRNA for tissue factor, one important trigger for thrombin generation in the adult, was detected in embryonic epithelia from E9.5-12.5. In several instances, tissue factor-expressing epithelia were surrounded by thrombin receptor-expressing mesenchyme. These data suggest a possible role for the thrombin receptor in development. The finding of robust thrombin receptor expression before prothrombin mRNA was detected raises the question of whether other proteases or peptide ligands can activate the thrombin receptor. Images Figure 1 Figure 2

  6. Purification and characterization of a prothrombin-activating protease from Nephila clavata.

    PubMed

    Joo, Han-Seung; Park, Gun-Chun; Cho, Woo Ri; Tak, Eunsik; Paik, Seung R; Chang, Chung-Soon

    2002-03-01

    We report upon the purification and characterization of a novel prothrombin-activating enzyme from the body fluid (total homogenates of isolated digestive tract without eggs, spinnerets and silk glands) of the spider, Nephila clavata by a combination of acetone fractionation, ion exchange, and Soybean trypsin inhibitor-Sepharose chromatography. Analysis of the purified enzyme with SDS-PAGE and gel filtration revealed a single polypeptide chain with an apparent molecular weight of 24kDa. The proteolytic activity of the enzyme was stable up to 50 degrees C, however, it became unstable over 55 degrees C. The enzyme had an optimum pH of 8, and Ca(2+) was not required for the enzyme activity. According to inhibition profiles obtained with several serine protease inhibitors such as PMSF and benzamidine, the purified protease is a member of the serine proteases. Bz-Ile-Glu(gamma-OR)- Gly-Arg-pNA and Z-Arg-Gly-Arg-pNA which are known as substrates for factor Xa, were hydrolyzed favorably by the enzyme. And the Nephila protease could produce thrombin from prothrombin at nM range, and form the turbid ring using fibrinogen-agarose plate. The results obtained confirmed that the purified protease is a potent prothrombin-activating activity belonging to the family of serine protease.

  7. Peak Plasma Concentration of Azithromycin and Treatment Responses in Mycobacterium avium Complex Lung Disease.

    PubMed

    Jeong, Byeong-Ho; Jeon, Kyeongman; Park, Hye Yun; Moon, Seong Mi; Kim, Su-Young; Lee, Soo-Youn; Shin, Sung Jae; Daley, Charles L; Koh, Won-Jung

    2016-10-01

    Macrolides, such as azithromycin (AZM) and clarithromycin, are the cornerstones of treatment for Mycobacterium avium complex lung disease (MAC-LD). Current guidelines recommend daily therapy with AZM for cavitary MAC-LD and intermittent therapy for noncavitary MAC-LD, but the effectiveness of these regimens has not been thoroughly investigated. This study evaluated associations between microbiological response and estimated peak plasma concentrations (Cmax) of AZM. The AZM Cmax was measured in patients receiving daily therapy (250 mg of AZM daily, n = 77) or intermittent therapy (500 mg of AZM three times weekly, n = 89) for MAC-LD and daily therapy for Mycobacterium abscessus complex LD (MABC-LD) (250 mg of AZM daily, n = 55). The AZM Cmax was lower with the daily regimen for MAC-LD (median, 0.24 μg/ml) than with the intermittent regimen for MAC-LD (median, 0.65 μg/ml; P < 0.001) or daily therapy for MABC-LD (median, 0.53 μg/ml; P < 0.001). After adjusting for confounding factors, AZM Cmax was independently associated with favorable microbiological responses in MAC-LD patients receiving a daily regimen (adjusted odds ratio [aOR], 1.58; 95% confidence interval [CI], 1.01 to 2.48; P = 0.044) but not an intermittent regimen (aOR, 0.85; 95% CI, 0.58 to 1.23, P = 0.379). With the daily AZM-based multidrug regimen for MAC-LD, a low AZM Cmax was common, whereas a higher AZM Cmax was associated with favorable microbiologic responses. The results also suggested that the addition of rifampin may lower AZM Cmax When a daily AZM-based multidrug regimen is used for treating severe MAC-LD, such as cavitary disease, the currently recommended AZM dose might be suboptimal. (This study has been registered at ClinicalTrials.gov under identifier NCT00970801.). Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  8. Thermal isoelectric precipitation of alpha-lactalbumin from a whey protein concentrate: Influence of protein-calcium complexation.

    PubMed

    Bramaud, C; Aimar, P; Daufin, G

    1995-07-20

    The selective precipitation of alpha-lactalbumin (alpha-LA) at a pH around its isoelectric point (4.2) under heat treatment is the basis for a fractionation process of whey proteins. As precipitation is a phenomenon dependent on the protein hydrophobicity, and as the release of the tightly bound calcium occurring at pH around 4 modifies the alpha-LA hydrophobicity, the specific role of calcium on isoelectric precipitation is investigated. A study of the extent of alpha-LA precipitation in a whey protein concentrate under various operating conditions of pH, temperature, protein concentration, and calcium content is presented. We propose a mechanism for this phenomenon as a combination of a complexation equilibrium and of an irreversible precipitation, to account for the influence of temperature, alpha-LA concentration total ionic content, and calcium concentration, and also to estimate the complexation equilibrium constant. (c) 1995 John Wiley & Sons, Inc.

  9. Chemical Swarming: Depending on Concentration, an Amphiphilic Ruthenium Polypyridyl Complex Induces Cell Death via Two Different Mechanisms

    PubMed Central

    Siewert, Bianka; van Rixel, Vincent H. S.; van Rooden, Eva J.; Hopkins, Samantha L.; Moester, Miriam J. B.; Ariese, Freek; Siegler, Maxime A.

    2016-01-01

    Abstract The crystal structure and in vitro cytotoxicity of the amphiphilic ruthenium complex [3](PF6)2 are reported. Complex [3](PF6)2 contains a Ru−S bond that is stable in the dark in cell‐growing medium, but is photosensitive. Upon blue‐light irradiation, complex [3](PF6)2 releases the cholesterol–thioether ligand 2 and an aqua ruthenium complex [1](PF6)2. Although ligand 2 and complex [1](PF6)2 are by themselves not cytotoxic, complex [3](PF6)2 was unexpectedly found to be as cytotoxic as cisplatin in the dark, that is, with micromolar effective concentrations (EC50), against six human cancer cell lines (A375, A431, A549, MCF‐7, MDA‐MB‐231, and U87MG). Blue‐light irradiation (λ=450 nm, 6.3 J cm−2) had little influence on the cytotoxicity of [3](PF6)2 after 6 h of incubation time, but it increased the cytotoxicity of the complex by a factor 2 after longer (24 h) incubation. Exploring the unexpected biological activity of [3](PF6)2 in the dark elucidated an as‐yet unknown bifaceted mode of action that depended on concentration, and thus, on the aggregation state of the compound. At low concentration, it acts as a monomer, inserts into the membrane, and can deliver [1]2+ inside the cell upon blue‐light activation. At higher concentrations (>3–5 μm), complex [3](PF6)2 forms supramolecular aggregates that induce non‐apoptotic cell death by permeabilizing cell membranes and extracting lipids and membrane proteins. PMID:27373895

  10. Efficient Sensitized Z→E Photoisomerization of an Iridium(III)-Azobenzene Complex over a Wide Concentration Range.

    PubMed

    Moreno, Javier; Grubert, Lutz; Schwarz, Jutta; Bléger, David; Hecht, Stefan

    2017-09-07

    To improve the sensitized Z→E photoisomerization of azobenzenes, and circumvent the threshold concentration necessary for the bimolecular photoinduced electron transfer reaction to generate the rapidly isomerizing Z-azobenzene radical anion, an Ir(III) complex with a covalently tethered azobenzene fragment was synthesized. Selective irradiation of the (1) MLCT band of the Ir(III) complex induced an efficiently sensitized photoswitching of the dyad over a wide concentration range and even at high dilution. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Eu(III)-Fulvic Acid Complexation: Evidence of Fulvic Acid Concentration Dependent Interactions by Time-Resolved Luminescence Spectroscopy.

    PubMed

    Kouhail, Yasmine Z; Benedetti, Marc F; Reiller, Pascal E

    2016-04-05

    Europium speciation is investigated by time-resolved luminescence spectroscopy (TRLS) in the presence of Suwannee River fulvic acid (SRFA). From complexation isotherms built at different total Eu(III) concentrations, pH values, ionic strength, and SRFA concentrations, it appears that two luminescence behaviors of Eu(III) are occurring. The first part, at the lowest CSRFA values, is showing the typical luminescence evolution of Eu(III) complexed by humic substances--that is, the increase of the asymmetry ratio between the (5)D0 → (7)F2 and (5)D0 → (7)F1 transitions up to a plateau--, and the occurrence of a biexponential decay--the first decay being faster than free Eu(3+). At higher CSRFA, a second luminescence mode is detected as the asymmetry ratio is increasing again after the previous plateau, and could correspond to the formation of another type of complex, and/or it can reflect a different spatial organization of complexed europium within the SRFA structure. The luminescence decay keeps on evolving but link to hydration number is not straightforward due to quenching mechanisms. The Eu(III) chemical environment evolution with CSRFA is also ionic strength dependent. These observations suggest that in addition to short-range interactions--intraparticulate complexation--, there might be interactions at longer range--interparticulate repulsion--between particles that are complexing Eu(III) at high CSRFA. These interactions are not yet accounted by the different complexation models.

  12. Sec1p Binds to Snare Complexes and Concentrates at Sites of Secretion

    PubMed Central

    Carr, Chavela M.; Grote, Eric; Munson, Mary; Hughson, Frederick M.; Novick, Peter J.

    1999-01-01

    Proteins of the Sec1 family have been shown to interact with target-membrane t-SNAREs that are homologous to the neuronal protein syntaxin. We demonstrate that yeast Sec1p coprecipitates not only the syntaxin homologue Ssop, but also the other two exocytic SNAREs (Sec9p and Sncp) in amounts and in proportions characteristic of SNARE complexes in yeast lysates. The interaction between Sec1p and Ssop is limited by the abundance of SNARE complexes present in sec mutants that are defective in either SNARE complex assembly or disassembly. Furthermore, the localization of green fluorescent protein (GFP)-tagged Sec1p coincides with sites of vesicle docking and fusion where SNARE complexes are believed to assemble and function. The proposal that SNARE complexes act as receptors for Sec1p is supported by the mislocalization of GFP-Sec1p in a mutant defective for SNARE complex assembly and by the robust localization of GFP-Sec1p in a mutant that fails to disassemble SNARE complexes. The results presented here place yeast Sec1p at the core of the exocytic fusion machinery, bound to SNARE complexes and localized to sites of secretion. PMID:10427089

  13. Genetic diminution of circulating prothrombin ameliorates multiorgan pathologies in sickle cell disease mice.

    PubMed

    Arumugam, Paritha I; Mullins, Eric S; Shanmukhappa, Shiva Kumar; Monia, Brett P; Loberg, Anastacia; Shaw, Maureen A; Rizvi, Tilat; Wansapura, Janaka; Degen, Jay L; Malik, Punam

    2015-10-08

    Sickle cell disease (SCD) results in vascular occlusions, chronic hemolytic anemia, and cumulative organ damage. A conspicuous feature of SCD is chronic inflammation and coagulation system activation. Thrombin (factor IIa [FIIa]) is both a central protease in hemostasis and a key modifier of inflammatory processes. To explore the hypothesis that reduced prothrombin (factor II [FII]) levels in SCD will limit vaso-occlusion, vasculopathy, and inflammation, we used 2 strategies to suppress FII in SCD mice. Weekly administration of FII antisense oligonucleotide "gapmer" to Berkeley SCD mice to selectively reduce circulating FII levels to ∼10% of normal for 15 weeks significantly diminished early mortality. More comprehensive, long-term comparative studies were done using mice with genetic diminution of circulating FII. Here, cohorts of FII(lox/-) mice (constitutively carrying ∼10% normal FII) and FII(WT) mice were tracked in parallel for a year following the imposition of SCD via hematopoietic stem cell transplantation. This genetically imposed suppression of FII levels resulted in an impressive reduction in inflammation (reduction in leukocytosis, thrombocytosis, and circulating interleukin-6 levels), reduced endothelial cell dysfunction (reduced endothelial activation and circulating soluble vascular cell adhesion molecule), and a significant improvement in SCD-associated end-organ damage (nephropathy, pulmonary hypertension, pulmonary inflammation, liver function, inflammatory infiltration, and microinfarctions). Notably, all of these benefits were achieved with a relatively modest 1.25-fold increase in prothrombin times, and in the absence of hemorrhagic complications. Taken together, these data establish that prothrombin is a powerful modifier of SCD-induced end-organ damage, and present a novel therapeutic target to ameliorate SCD pathologies.

  14. Genetic diminution of circulating prothrombin ameliorates multiorgan pathologies in sickle cell disease mice

    PubMed Central

    Arumugam, Paritha I.; Mullins, Eric S.; Shanmukhappa, Shiva Kumar; Monia, Brett P.; Loberg, Anastacia; Shaw, Maureen A.; Rizvi, Tilat; Wansapura, Janaka; Degen, Jay L.

    2015-01-01

    Sickle cell disease (SCD) results in vascular occlusions, chronic hemolytic anemia, and cumulative organ damage. A conspicuous feature of SCD is chronic inflammation and coagulation system activation. Thrombin (factor IIa [FIIa]) is both a central protease in hemostasis and a key modifier of inflammatory processes. To explore the hypothesis that reduced prothrombin (factor II [FII]) levels in SCD will limit vaso-occlusion, vasculopathy, and inflammation, we used 2 strategies to suppress FII in SCD mice. Weekly administration of FII antisense oligonucleotide “gapmer” to Berkeley SCD mice to selectively reduce circulating FII levels to ∼10% of normal for 15 weeks significantly diminished early mortality. More comprehensive, long-term comparative studies were done using mice with genetic diminution of circulating FII. Here, cohorts of FIIlox/− mice (constitutively carrying ∼10% normal FII) and FIIWT mice were tracked in parallel for a year following the imposition of SCD via hematopoietic stem cell transplantation. This genetically imposed suppression of FII levels resulted in an impressive reduction in inflammation (reduction in leukocytosis, thrombocytosis, and circulating interleukin-6 levels), reduced endothelial cell dysfunction (reduced endothelial activation and circulating soluble vascular cell adhesion molecule), and a significant improvement in SCD-associated end-organ damage (nephropathy, pulmonary hypertension, pulmonary inflammation, liver function, inflammatory infiltration, and microinfarctions). Notably, all of these benefits were achieved with a relatively modest 1.25-fold increase in prothrombin times, and in the absence of hemorrhagic complications. Taken together, these data establish that prothrombin is a powerful modifier of SCD-induced end-organ damage, and present a novel therapeutic target to ameliorate SCD pathologies. PMID:26286849

  15. Impact of telavancin on prothrombin time and activated partial thromboplastin time as determined using point-of-care coagulometers.

    PubMed

    Ero, Michael P; Harvey, Nathaniel R; Harbert, Jack L; Janc, James W; Chin, Kay H; Barriere, Steven L

    2014-01-01

    Telavancin is approved in the United States, Canada, and Europe (At the time of submission, the telavancin European marketing authorization for nosocomial pneumonia was suspended until Theravance provides evidence of a new European Medicines Agency approved supplier) as an antibiotic to treat certain Gram-positive bacterial skin infections. Telavancin has been shown to prolong plasmatic prothrombin (PT) and activated partial thromboplastin (aPTT) clotting times in clinical diagnostic lab-based assays. In this study, we evaluated the potential for telavancin to prolong whole blood PT/International Normalized Ratio (INR) and aPTT tests on point-of-care (POC) instruments. Whole blood collected from 8 healthy subjects was supplemented with telavancin to final concentrations of 0, 10, 20, and 100 μg/ml. Final concentrations were selected to match trough, twice trough, and peak plasma levels following the approved 10 mg/kg dose. Four widely employed POC coagulation instruments were chosen to be representative of the POC platforms currently in use.. These systems were the Roche Coaguchek XS, the Abbott iSTAT, the ITC Hemochron SIG+, and the Alere INRatio2 POC devices. The PT/INR measured by the Coaguchek XS showed the greatest sensitivity to the presence of telavancin. The PT/INR measured by the Hemochron SIG+ and iSTAT were sensitive to telavancin but to a lesser extent. The INRatio2 was the least sensitive to the presence of telavancin when testing the whole blood PT/INR. Only the Hemochron SIG+ device was capable of measuring aPTT and showed a concentration-dependent increase in aPTT. This study supports the current recommendation that PT and aPTT monitoring be conducted immediately to the next dose of telavancin when coagulation parameters are tested using POC instrumentation.

  16. Prothrombin-activator (thromboplastin) generation in the blood of water snake (Natrix piscator).

    PubMed

    Srivastava, V M; Dube, B; Dube, R K; Agarwal, G P

    1981-12-23

    The generation of prothrombin-activator (thromboplastin) in water snake (Natrix piscator) is clearly delayed, compared to a mammalian system, but the final activity is well comparable to that in man, when homologous sources of "phospholipid" (erythrocyte-lysate) and of substrate plasma are employed in one stage "thromboplastin generation test". The use of heterologous source of either of the above reagents resulted in significantly longer clotting times; hence the need for homologous source of above reagents in the test is emphasized for comparative studies on animal haemostasis.

  17. Ratcheting of the substrate from the zymogen to proteinase conformations directs the sequential cleavage of prothrombin by prothrombinase

    PubMed Central

    Bianchini, Elsa P.; Orcutt, Steven J.; Panizzi, Peter; Bock, Paul E.; Krishnaswamy, Sriram

    2005-01-01

    Prothrombinase catalyzes thrombin formation by the ordered cleavage of two peptide bonds in prothrombin. Although these bonds are likely ≈36 Å apart, sequential cleavage of prothrombin at Arg-320 to produce meizothrombin, followed by its cleavage at Arg-271, are both accomplished by equivalent exosite interactions that tether each substrate to the enzyme and facilitate presentation of the scissile bond to the active site of the catalyst. We show that impairing the conformational transition from zymogen to active proteinase that accompanies the formation of meizothrombin has no effect on initial cleavage at Arg-320 but inhibits subsequent cleavage at Arg-271. Full thermodynamic rescue of this defective mutant was achieved by stabilizing the proteinase-like conformation of the intermediate with a reversible, active site-specific inhibitor. Irreversible stabilization of intact prothrombin in a proteinase-like state, even without prior cleavage at Arg-320, also enhanced cleavage at Arg-271. Our results indicate that the sequential presentation and cleavage of the two scissile bonds in prothrombin activation is accomplished by substrate bound either in the zymogen or proteinase conformations. The ordered cleavage of prothrombin by prothrombinase is driven by ratcheting of the substrate from the zymogen to the proteinase-like states. PMID:16006504

  18. A model for the unique role of factor Va A2 domain extension in the human ternary thrombin-generating complex.

    PubMed

    Shim, Joong-Youn; Lee, Chang Jun; Wu, Sangwook; Pedersen, Lee G

    2015-04-01

    An all-atom human ternary model for the prothrombinase-prothrombin complex, including metal ions and post-translationally modified residues, was constructed from existing X-ray crystal structures. The factor Xa-prothrombin interface was taken from an existing ternary model, which locates the active site of factor Xa in the vicinity of prothrombin cleavage positions. The three sulfotyrosine residues at the C-terminal sequence of factor Va A2 domain are accommodated by modelling rational interactions with positively charged patches on the surface of prothrombin. The entire model is then solvent-equilibrated with molecular dynamics. This ternary model for the thrombin-generating complex provides an estimate as to the role of the C-terminus of the factor Va A2 domain: to establish an interface between FXa and prothrombin and to stabilize the orientation of this interface. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Feasibility of antibody-poly(glutamic acid) complexes: preparation of high-concentration antibody formulations and their pharmaceutical properties.

    PubMed

    Izaki, Shunsuke; Kurinomaru, Takaaki; Maruyama, Takuya; Uchida, Takayuki; Handa, Kenji; Kimoto, Tomoaki; Shiraki, Kentaro

    2015-06-01

    Development of high-concentration antibody formulations for subcutaneous administration remains challenging. Recently, a precipitation-redissolution method was proposed to prepare suspensions or precipitates of salt-dissociable protein-poly(amino acid) complexes. To elucidate the utility of this method for protein therapy, we investigated the feasibility of a precipitation-redissolution method using poly(amino acid) for high-concentration antibody formulation. Omalizumab and adalimumab formulations of 150 mg/mL could be prepared using poly-l-glutamic acid (polyE) from low-concentration stock solutions. Enzyme-linked immunosorbent assay, circular dichroism, and size-exclusion chromatography revealed that the formation of antibody-polyE complex and precipitation-redissolution process did not significantly affect the immunoreactivity or secondary structure of the antibodies. The precipitation-redissolution method was less time-consuming and more effective than lyophilization-redissolution, evaporation-redissolution, and ultrafiltration from the viewpoint of final yield. Scalability was confirmed from 400 μL to 1.0 L. The general toxicity and pharmacokinetic profiles of the antibody-polyE complex formulations were similar to those of conventional antibody formulations. These results suggested that the precipitation-redissolution method using poly(amino acid) has great potential as a concentration method for antibody formulation and medicinal use.

  20. Molecular characterization of factor V leiden G1691A and prothrombin G20210A mutations in Saudi newborns with stroke.

    PubMed

    Gawish, Gihan E-H

    2011-10-01

    This study examined a possible association between the mutations related to Factor V Leiden and Factor II (prothrombin) and stroke in Saudi neonates. A multiplex PCR was established to detect Factor V Leiden G1691A and prothrombin G20210A mutations in 72 neonatal stroke subjects and 70 healthy adult controls with no family history of thromboembolic diseases. The frequency of the homozygous normal genotype (GG) of both genes was found to be significantly lower in the stroke subjects than in the controls (P < 0.0001). The stroke cases also had higher frequencies of the combined Factor II heterozygous mutant form (GA) and the homozygous normal Factor V (GG) (P < 0.0001) and of the combined heterozygous Factor V and the homozygous normal Factor II genotypes (GG) (P = 0.0) than controls. The study concluded that prothrombin and Factor V Leiden may be important risk factors for neonatal stroke in Saudi children.

  1. Vascular behcet and mutations in thrombogenic genes: methylene tetrahydrofolate reductase, factor V, and prothrombin.

    PubMed

    Dagan, Efrat; Baruch, Yoav; Fiorilli, Massimo; Rozenbaum, Michael; Rosner, Itzhak; Gershoni-Baruch, Ruth

    2012-01-01

    Vasculitis, thrombophlebitis, arterial aneurysms, and occlusions occur in about 25% of patients with Behçet's disease (BD). The common inherited gene defects, factor V (FV) 1691A (Leiden), methylene tetrahydrofolate reductase (MTHFR) 677T, and prothrombin 20210A, are known risk factors for thrombosis. The aim of the study was to evaluate the contribution of these mutations to thrombosis in Israeli patients with BD. Fifty-four patients with BD (n=54; 27 men and 27 women) underwent clinical and genetic evaluation. Most patients (n=43; 79.6%) were of Arab descent (31 sporadic and 12 familial cases from 4 families), and 11 patients (20.4%) were of Jewish descent (all sporadic cases). The FV Leiden mutation was identified in five patients (9.2%), and eight patients were MTHFR 677TT homozygotes (14.8%). None had the 20210A mutant prothrombin allele. No statistical differences between carriers and noncarriers with regards to demographic and disease manifestations were calculated. Arabs were diagnosed earlier than Jewish patients (25.8±11.6 compared with 37.2±10.7, p=0.01, respectively), but Jewish patients had, respectively, more events of deep vein thrombosis (DVT) compared with Arabs (3 of 11, 27.3% and 3 of 43, 7%, p=0.09). Thrombotic events in our patients with BD were not associated with variations in thrombophilic genes.

  2. Different outcome of six homozygotes for prothrombin A20210A gene variant

    PubMed Central

    Di Micco, Pierpaolo; Di Fiore, Rosanna; Niglio, Alferio; Quaranta, Sandro; Angiolillo, Antonella; Cardillo, Giuseppe; Castaldo, Giuseppe

    2008-01-01

    Prothrombin G20210A gene variant (FII G20210A) is a risk factor for venous thrombotic disease while conflicting results have been reported for the risk of arterial thrombotic events. However, vascular episodes were absent in up to 40% of the 67 homozygotes for the G20210A described so far, which indicates that the clinical expression depends on additional risk/trigger factors. We describe six homozygotes for the G20210A variant, among which the first pair of siblings (cases n. 3 and 4) reported so far that displayed a strongly heterogeneous clinical outcome. Case 1, a female of 27 years, developed a full thrombosis of common femoral, superficial and popliteal veins. She assumed oral contraceptives in the last two years. Case n. 2, 34 years old, suffered of recurrent pregnancy loss in absence of any causative alteration. Cases n. 3 and n. 5 experienced arterial thrombotic disease, i.e., juvenile myocardial infarction (40 years old) and stroke (48 years old), respectively, in absence of other risk factors. Finally, cases n. 4 and 6 identified as homozygotes for the FII G20210A variant being consanguineous of symptomatic subjects bearing the variant, did not experience any episode of venous nor arterial disease. Both of them have chronic liver disease with an impairement of the prothrombin time INR. Thus, homozygotes for the G20210A are at risk for arterial (in addition to venous) thromobotic events; chronic liver disease might modulate this risk. PMID:18627609

  3. Extraction of metals from complex sulfide nickel concentrates by low-temperature chlorination roasting and water leaching

    NASA Astrophysics Data System (ADS)

    Xu, Cong; Cheng, Hong-wei; Li, Guang-shi; Lu, Chang-yuan; Lu, Xiong-gang; Zou, Xing-li; Xu, Qian

    2017-04-01

    The recovery of valuable metals from complex sulfide concentrates was investigated via chlorination roasting followed by water leaching. A reaction process is proposed on the basis of previous studies and the results of our preliminary experiments. During the process, various process parameters were studied, including the roasting temperature, the addition of NH4Cl, the roasting time, the leaching time, and the liquid-to-solid ratio. The roasted products and leach residues were characterized by X-ray diffraction and vibrational spectroscopy. Under the optimum condition, 95% of Ni, 98% of Cu, and 88% of Co were recovered. In addition, the removal of iron was studied in the water leaching stage. The results demonstrate that this process provides an effective approach for extracting multiple metals from complex concentrates or ores.

  4. Do Factor V Leiden and Prothrombin G20210A Mutations Predict Recurrent Venous Thromboembolism in Older Patients?

    PubMed

    Méan, Marie; Limacher, Andreas; Stalder, Odile; Angelillo-Scherrer, Anne; Alberio, Lorenzo; Fontana, Pierre; Beer, Hans-Jürg; Rodondi, Nicolas; Lämmle, Bernhard; Aujesky, Drahomir

    2017-10-01

    The value of genetic thrombophilia testing in elderly patients with an unprovoked venous thromboembolism is unclear. We assessed whether the Factor V Leiden and the prothrombin G20210A mutation are associated with recurrent venous thromboembolism in elderly patients in a prospective multicenter cohort study. We genotyped the Factor V Leiden and the prothrombin G20210A mutation in 354 consecutive in- and outpatients aged ≥65 years with a first unprovoked venous thromboembolism from 9 Swiss hospitals. Patients and managing physicians were blinded to testing results. The outcome was recurrent symptomatic venous thromboembolism during follow-up. We examined the association between the Factor V Leiden and the prothrombin G20210A mutation and venous thromboembolism recurrence using competing risk regression, adjusting for age, sex, and periods of anticoagulation as a time-varying covariate. Overall, 9.0% of patients had a Factor V Leiden and 3.7% had a prothrombin G20210A mutation. At 36 months of follow-up, patients with a Factor V Leiden and a prothrombin G20210A mutation had a cumulative incidence of recurrent venous thromboembolism of 12.9% (95% confidence interval [CI], 5.1%-30.8%) and 18.5% (95% CI, 4.9%-56.5%), respectively, compared with 16.7% (95% CI, 12.5%-22.1%) of patients without mutation (P = .91 by the log-rank test). After adjustment, neither the Factor V Leiden (sub-hazard ratio 0.98; 95% CI, 0.35-2.77) nor the prothrombin G20210A mutation (sub-hazard ratio 1.15; 95% CI, 0.25-5.19) was associated with recurrent venous thromboembolism. Our results suggest that testing for genetic thrombophilia may not be beneficial in elderly patients with a first unprovoked venous thromboembolism. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Synthesis and reductive elimination of arylPd(ii) trifluoromethyl complexes: a remarkable concentration effect on chemoselectivity.

    PubMed

    Zhang, Song-Lin; Deng, Zhu-Qin

    2016-12-07

    Reductive elimination from Pd(ii) aryl trifluoromethyl complexes is a challenging and elusive step which is accompanied by a number of kinetically more favorable side reactions giving rising to a complex mixture. We report herein the synthesis and isolation of several arylPd(ii) trifluoromethyl complexes (2a-c) and study their electronic structures, photophysical properties and reductive elimination reactivities. A remarkable concentration effect on chemoselectivity is observed for thermal decomposition of (Xantphos)Pd(ii)(Ar)(CF3) (2c) that favors the formation of Ar-CF3 at lower concentrations, but gives increasingly more Ar-Ar homocoupling product to a dominant extent as the concentration of 2c increases. This is solid evidence for the involvement of an intermolecular Ar/CF3 ligand exchange/Ar-Ar reductive elimination mechanism that has been proposed based on DFT computational studies. The interplay between theory and experiment provides valuable insights into the mechanism and kinetics of the key elementary reaction of reductive elimination at Pd(ii), and may thus prompt the design of more efficient Pd-mediated nucleophilic trifluoromethylation reactions.

  6. Influence of tableting forces and lubricant concentration on the adhesion strength in complex layer tablets.

    PubMed

    Dietrich, P; Bauer-Brandl, A; Schubert, R

    2000-07-01

    The strength of adhesion in complex two-layer tablets is assessed using statistical methods with respect to the applied tableting forces for the first layer and for applying the second layer on the first, as well as regarding the fraction of the lubricant. These results, obtained on a single-punch tablet press, are compared with the results for three-layer tablets produced on a rotary press at production scale. The strongest negative influence on adhesion strength was exerted by the amount of lubricant in the central layer. As expected, compression forces for central-layer tableting also had a negative effect, whereas the compression forces for complex layer tableting exerted a positive effect on layer adhesion. The validity of the derived model equation was proved by experiments: It was shown that the adhesion strength in complex layer tablets produced in production scale can be predicted from laboratory-scale experiments. This makes optimization of the formulation and parameter settings at an early stage of development possible.

  7. Evidence for the complex relationship between free amino acid and sugar concentrations and acrylamide-forming potential in potato

    PubMed Central

    Muttucumaru, N; Powers, SJ; Elmore, JS; Briddon, A; Mottram, DS; Halford, NG

    2014-01-01

    Free amino acids and reducing sugars participate in the Maillard reaction during high-temperature cooking and processing. This results not only in the formation of colour, aroma and flavour compounds, but also undesirable contaminants, including acrylamide, which forms when the amino acid that participates in the reaction is asparagine. In this study, tubers of 13 varieties of potato (Solanum tuberosum), which had been produced in a field trial in 2010 and sampled immediately after harvest or after storage for 6 months, were analysed to show the relationship between the concentrations of free asparagine, other free amino acids, sugars and acrylamide-forming potential. The varieties comprised five that are normally used for crisping, seven that are used for French fry production and one that is used for boiling. Acrylamide formation was measured in heated flour, and correlated with glucose and fructose concentration. In French fry varieties, which contain higher concentrations of sugars, acrylamide formation also correlated with free asparagine concentration, demonstrating the complex relationship between precursor concentration and acrylamide-forming potential in potato. Storage of the potatoes for 6 months at 9°C had a significant, variety-dependent impact on sugar and amino acid concentrations and acrylamide-forming potential. PMID:25540460

  8. Determination of size- and number-based concentration of silica nanoparticles in a complex biological matrix by online techniques.

    PubMed

    Bartczak, Dorota; Vincent, Phil; Goenaga-Infante, Heidi

    2015-06-02

    We propose for the first time methodology for the determination of a number-based concentration of silica (SiO2) nanoparticles (NP) in biological serum using nanoparticle tracking analysis (NTA) as the online detector for asymmetric flow field-flow fractionation (AF4). The degree of selectivity offered by AF4 was found necessary to determine reliably number-based concentration of the measured NP in the complex matrix with a relative measurement error of 5.1% (as relative standard deviation, n = 3) and without chemical sample pretreatment. The simultaneous online coupling to other size and concentration detectors, such as multiangle light scattering (MALS) and ICPMS, for the measurement of the same NP suspension, was used to confirm the particle size determined with NTA and the equivalent particle number determined by AF4/NTA, respectively. The size- and number-based concentration data obtained by independent techniques were in a good agreement. The developed methodology can easily be extended to other types of particles or particle suspensions and other complex matrices provided that the particle size is above the limit of detection for NTA.

  9. A Multiplex Allele Specific Polymerase Chain Reaction (MAS-PCR) for the Detection of Factor V Leiden and Prothrombin G20210A.

    PubMed

    Bagheri, Morteza; Rad, Isa Abdi

    2011-01-01

    In order to determine the frequencies of factor V Leiden and prothrombin G20210A point mutations in the Iranian population with Azeri Turkish origin. 120 unrelated individuals from general population randomly selected and were examined for factor V Leiden and prothrombin G20210A mutations using a multiplex allele specific polymerase chain reaction (MAS-PCR) assayOutcomes: The frequency of prothrombin G20210A mutation was 2.08%, which means 5 chromosomes out of 240 chromosomes had prothrombin G20210A mutation. The distribution of prothrombin 20210 GG, GA, AA genotypes and prothrombin 20210A allele were 37(92.5%), 3(7.5%), 0(0%) and 3(3.75%) in males and 78(97.5%), 2(2.5%), 0(0%) and 2(1.25%) in females, respectively. Factor V Leiden was not found in our tested group (zero chromosomes out of 240 chromosomes). Analysis of the observed frequencies in the studied groups indicates that there is no statistically significant difference between females and males, regarding prothrombin G20210A mutation (p value>0.05). This is the first study in its own kind in this population and implies that the frequency of Factor V Leiden G1691A (R506Q, FV-Leiden) allele is extremely low but the prothrombin G20210A mutation is more frequent in the tested group.

  10. A Multiplex Allele Specific Polymerase Chain Reaction (MAS-PCR) for the Detection of Factor V Leiden and Prothrombin G20210A

    PubMed Central

    Bagheri, Morteza; Rad, Isa Abdi

    2011-01-01

    ABSTRACT Introduction: In order to determine the frequencies of factor V Leiden and prothrombin G20210A point mutations in the Iranian population with Azeri Turkish origin. Material and methods: 120 unrelated individuals from general population randomly selected and were examined for factor V Leiden and prothrombin G20210A mutations using a multiplex allele specific polymerase chain reaction (MAS-PCR) assay Outcomes: The frequency of prothrombin G20210A mutation was 2.08%, which means 5 chromosomes out of 240 chromosomes had prothrombin G20210A mutation. The distribution of prothrombin 20210 GG, GA, AA genotypes and prothrombin 20210A allele were 37(92.5%), 3(7.5%), 0(0%) and 3(3.75%) in males and 78(97.5%), 2(2.5%), 0(0%) and 2(1.25%) in females, respectively. Factor V Leiden was not found in our tested group (zero chromosomes out of 240 chromosomes). Analysis of the observed frequencies in the studied groups indicates that there is no statistically significant difference between females and males, regarding prothrombin G20210A mutation (p value>0.05). Conclusions: This is the first study in its own kind in this population and implies that the frequency of Factor V Leiden G1691A (R506Q, FV-Leiden) allele is extremely low but the prothrombin G20210A mutation is more frequent in the tested group. PMID:21977183

  11. Clinical and biochemical characterization of the prothrombin Belgrade mutation in a large Serbian pedigree: new insights into the antithrombin resistance mechanism.

    PubMed

    Miljic, P; Gvozdenov, M; Takagi, Y; Takagi, A; Pruner, I; Dragojevic, M; Tomic, B; Bodrozic, J; Kojima, T; Radojkovic, D; Djordjevic, V

    2017-01-11

    Essentials Prothrombin Belgrade mutation leads to antithrombin resistance. Clinical and biochemical phenotypes in a large family with this mutation were investigated. In carriers, we detected decreased factor II activity and increased endogenous thrombin potential. Prothrombin Belgrade mutation represents a strong prothrombotic risk factor.

  12. Electron probe microanalysis of the dopant concentrations in complex perovskite ferroelectrics

    NASA Astrophysics Data System (ADS)

    Samardžija, Z.

    2016-02-01

    Quantitative EPMA-WDS microanalyses were applied for the compositional characterisation of complex perovskite ferroelectrics based on cerium-doped barium titanate, a solid solution between lead-magnesium-niobate/lead-titanate and niobium-doped barium- bismuth-titanate. The analyses were optimized for high analytical sensitivity, precision and an ultimate accuracy of ≈ ± 1 % relative. The inherent problem with the WDS peak overlap of the Ce-Lα1 and Ba-Lβ1,4 spectral lines was solved by introducing overlap-correction methods in order to obtain consistent quantitative results for the Ce-doped BaTiO3. The quantitative results made it possible to obtain accurate chemical formulae for these materials, to determine the solubility of the dopants as well as to define the mode of the dopant incorporation and the charge-compensation mechanisms.

  13. Concentrations of selected chlorinated pesticides in shrimp collected from the Calcasieu River/Lake Complex, Louisiana

    SciTech Connect

    Murray, H.E.; Beck, J.N. )

    1990-05-01

    For several decades inland and coastal aquatic ecosystems have been affected by a multitude of synthetic chemical substances. This is a consequence of population growth and increased industrial and agricultural activity. Many of these chemicals, the by-products of their production, and degradation products ultimately find their way into the aquatic environment as pollutants. The extent to which these pollutants affect the environment and its inhabitants depends largely upon the quantity and nature of the particular compounds involved. Halogenated hydrocarbons, particularly polychlorinated biphenyls (PCBs), and the pesticide DDT and its degradation products have received much attention as environmental pollutants. Because of the economic importance of the shrimping industry to southwest Louisiana, the objective of this study was to analyze shrimp collected from the Calcasieu River/Lake Complex for the presence of selected chlorinated pesticides. The presence of these compounds within shrimp tissues would serve as an indicator for the extent of pollution throughout this important estuarine system.

  14. Effect of the Amine Concentration on Phase Evolution and Densification in Printed Films Using Cu(II) Complex Ink.

    PubMed

    Choi, Yun-Hyuk; Hong, Seong-Hyeon

    2015-07-28

    The nucleation and growth behavior of Cu nanoparticles during thermal heating of Cu(II) complex inks for printed Cu metallization were investigated, particularly focusing on the effects of the amine concentration on the microstructure evolution and electrical conductivity. Herein, the dual effects of hexylamine as a reducing agent dissociating the carboxyl group from the precursor and a capping agent hindering the subsequent growth of Cu nuclei were confirmed. On the basis of such dual effects of amine, the sufficient complexation of the Cu(II) precursor with a high amine concentration in the ink led to the single-route growth of Cu nanoparticles during thermal heating, which resulted in the dense film with a narrow particle size distribution exhibiting a high electrical conductivity. The electrical conductivity of the film could be further enhanced by a reducing atmosphere with formic acid. Significantly, the understanding of the ink chemistry and the nucleation and growth kinetics in the metal ion complex or metal-organic decomposition (MOD) ink can provide the design rules for the formulation of the solution-type inks to control the microstructure of printed metallization.

  15. Prothrombin time. Determination by a whole blood micro-method for control of anticoagulant therapy.

    PubMed

    GLOVER, R P; KUZELL, W C

    1961-07-01

    A micro technique that is here described for "prothrombin time" determinations, employing capillary whole blood, provides a range of values which is closely correlated with the Quick one-stage plasma method, thus providing inter-changeability of results both in normal persons and in patients who have been treated with anticoagulant drugs. Avoidance of the use of a water bath and centrifuge permit this technique to yield immediate results at the bedside, in the office or in the patient's home. The use of a whole blood instead of a plasma technique lends additional safety to control of anticoagulant medication, since it may reflect depression of clotting factors not apparent by the usual plasma methods.

  16. Effectiveness of holographic optical element module sensor in measuring blood prothrombin time

    NASA Astrophysics Data System (ADS)

    Lin, Yu-Cheng; Yen, Shih-Chieh; Cheng, Stone; Huang, Tony

    2014-07-01

    A small-form-factor holographic optical element (HOE) module, which was mounted on a dual-stage seesaw actuator, was utilized to evaluate blood coagulation in real time. The method involved assessing the decrease in transmitted light of the blood sample surface when the clotting is formed. The prothrombin time (PT) was measured by illumining and focusing a 635 nm laser beam onto the sample. As the fibrinogen turned into non-solute fibrin, the transmitted efficiency and total intensity of the reflected light from the reflector changed. A low-pass filter suppressed the noise in the coagulation-related transient response to yield accurate signals. Finally, the PT measurements were compared to those made classically using other optical sensors.

  17. Painless Livedoid Vasculopathy in a Patient with G20210A Prothrombin Gene Mutation.

    PubMed

    Mirrakhimov, Aibek E; Velasquez Kho, Erwin; Ali, Alaa

    2012-01-01

    87 year old Caucasian female with chronic painless non-healing ulcers over malleoli was admitted to the hospital. On a physical examination, there were two bilateral and laterally located malleoli ulcers with no discharge. A thorough work up was done: lower extremities venous and arterial Doppler ultrasound did not show any evidence of venous and arterial disease respectively. Heterozygous G20210A Prothrombin gene mutation was found, and the patient was started on anticoagulation. This case reports highlights a possibility of a painless livedoid vasculopathy presentation in a patient without significant past thrombotic events. Therefore, it is important to consider livedoid vasculopathy in the differential in a patient with painless ulcerative, atrophic and/or nodular skin lesions over the shins and malleoli.

  18. Heavy metals mobility associated with the molybdenum mining-concentration complex in the Buryatia Republic, Germany.

    PubMed

    Sarapulova, Angelina; Dampilova, Bayarma V; Bardamova, Irina; Doroshkevich, Svetlana G; Smirnova, Olga

    2017-04-01

    Mining of Dzhida ore deposits in Russia has caused the formation of a large tailings dam with technogenic sands and contamination of nearby district soils. Geochemical fractions of technogenic sands were divided by a sequential extraction procedure. The sampling points with maximum concentration of Pb, Cu, and Zn were selected for investigation of heavy metal mobility. Two previously described methods of heavy metal fractionation using selective extraction were applied: a procedure developed by the Community Bureau of Reference of the Commission of the European Communities (BCR procedure) and Tessier's fractionation scheme. Despite some differences in Pb extractions, the two procedures describe equally well the distribution of heavy metals on geochemical fractions. BCR procedure was chosen as a fast method of heavy metal mobile form estimation. For considered mining object, it is revealed that there are different characters of heavy metal mobility sequence in the soils Zn > Cu > Pb and technogenic sands Pb > Zn > Cu.

  19. A review of alcohol-impaired driving: the role of blood alcohol concentration and complexity of the driving task.

    PubMed

    Martin, Teri L; Solbeck, Patricia A M; Mayers, Daryl J; Langille, Robert M; Buczek, Yvona; Pelletier, Marc R

    2013-09-01

    The operation of a motor vehicle requires the integrity of sensory, motor, and intellectual faculties. Impairment of these faculties following the consumption of alcohol has been studied extensively through laboratory, closed-course and on-road driving, and epidemiological studies. The scientific literature was reviewed critically, with a focus on low-to-moderate blood alcohol concentrations (BAC ≤ 0.100%), to identify the most reliable determinants of alcohol-impaired driving. Variables such as age, gender, driving skill, and tolerance were shown to have limited impact on impairment. It was concluded the most relevant variables are BAC and complexity of the driving task. The scientific literature provides a high degree of confidence to support the conclusion that a BAC of 0.050% impairs faculties required in the operation of a motor vehicle. Whether impairment is apparent depends upon the complexity of the driving task, which applies to both study design and actual driving.

  20. Reconstructing the recent failure chronology of a multistage landslide complex using cosmogenic isotope concentrations: St Catherine's Point, UK

    NASA Astrophysics Data System (ADS)

    Barlow, John; Moore, Roger; Gheorghiu, Delia M.

    2016-09-01

    The pre-existing multistage landslide complex at St Catherine's Point comprises a series of large rotational and translational failures that form the western section of the Isle of Wight Undercliff, UK. Cosmogenic beryllium and aluminum concentrations extracted from chert samples of the Upper Greensand are used to date the most recent sequential failure events. We use our understanding of the failure mechanics and landslide geomorphology to produce a cosmogenic exposure model that incorporates pre-failure topography into our shielding calculations. This method allowed us to date two successive landslides at the site using 10Be, the most recent of which occurred ~ 1064 ± 348 (± 1 σ) 10Be years ago, much more recently than was previously thought. An earlier failure event is dated at ~ 3471 ± 348 10Be years, supporting the hypothesis that the St Catherine's Point landslide complex was reactivated by relative sea-level rise at the end of the Holocene Climatic Optimum period.

  1. Association between prothrombin gene polymorphisms and hereditary thrombophilia in Xinjiang Kazakhs population.

    PubMed

    Ge, Xiao-Hu; Zhu, Feng; Wang, Bing-Lin; Wang, Chang-Min; Zhu, Bing; Guan, Sheng; Ci, Hong-Bo; Sai, Li-Mu; Jiang, Xiao-Kui; Ren, Hao; Fang, Qing-Bo; Tian, Guang-Lei

    2014-03-01

    To assess the association between polymorphisms of prothrombin gene and hereditary thrombophilia in Xinjiang Kazakhs population. Through cross-sectional investigation, permanent Kazakh population of Ili Kazakh Autonomous Prefecture was selected as the study object to measure their antithrombin III (AT-III), protein C, protein S activity and activated C protein resistance value, thus defining the situation of the crowd's hereditary thrombophilia. Sequenom Massarray detection technology was used to conduct a genotype test of the six sites selected by the case and control groups. Haploview software was used to perform linkage disequilibrium analysis of the six sites, and the impact of the interaction between genetic variations and environment on hereditary thrombophilia was researched by the use of sum model. A total of 1005 Kazakh volunteers participated in the test (332 men and 673 women), average age (41.13 ± 11.50) years; the prevalence of hereditary thrombophilia in Xinjiang Kazakh population was 31.0%, and the prevalence of AT-III deficiency, protein C deficiency, protein S deficiency and activated protein C resistance was 16.4, 14.9, 20.6 and 7.8%, respectively. The difference in allele frequency of the hereditary thrombophilia patient group at rs3136447 and rs5896 sites was statistically significant (P = 0.0483 and P = 0.0302, respectively). rs5896 and rs2070852 had high linkage disequilibrium (r = 0.99), and constituted a single-domain block 1. The rs3136447 and the rs5896 polymorphisms located in the region of the prothrombin gene may be associated with hereditary thrombophilia in the Xinjiang Kazakhs population. There is additive interactive effect of rs5896 polymorphism (CT + TT) and smoke on hereditary thrombophilia.

  2. Saturation fluorimetry of complex organic compounds with a high local concentration of fluorophores (by the example of phytoplankton)

    SciTech Connect

    Maslov, D V; Ostroumov, E E; Fadeev, V V

    2006-02-28

    Saturation of fluorescence of complex organic compounds with a high local concentration of fluorescing molecules (fluorophores), when singlet-singlet annihilation makes a noticeable contribution to saturation, is considered. The fluorescence saturation curve is obtained analytically for the case of a rectangular temporal and spatial distribution of photons in a laser pulse. It is shown that the fluorescence saturation curve depends on the parameter {Phi}{sub 0}, which is proportional to the concentration of fluorescing molecules, and on the parameters A, B, and {alpha} describing the influence of singlet-singlet annihilation, bleaching of an optically thin layer, and nonstationarity of excitation, respectively. The fluorescence saturation curves are studied experimentally for compounds with a high local concentration of fluorescing molecules such as molecules of a monoculture of diatomic alga Thalassiosira weissflogii. The experimental fluorescence saturation curves are well described by the obtained analytic expression. The values of the parameter {Phi}{sub 0}, proportional to the concentration of chlorophyll a, and the parameter A (for the first time) are obtained from the alga fluorescence saturation curves. (laser applications and other topics in quantum electronics)

  3. Estimating chlorophyll concentrations in the optically complex waters of the North Aegean Sea from field and satellite ocean colour measurements

    NASA Astrophysics Data System (ADS)

    Drakopoulos, P. G.; Banks, A. C.; Kakagiannis, G.; Karageorgis, A. P.; Lagaria, A.; Papadopoulou, A.; Psarra, S.; Spyridakis, N.; Zervakis, V.

    2015-06-01

    In the Aegean Sea and Eastern Mediterranean there are large discrepancies between in situ and satellite ocean colour derived chlorophyll concentrations. The quantity that is monitored by ocean colour satellites and that can be used in the estimation of chlorophyll concentration is the remote sensing reflectance, defined as the ratio of the water leaving spectral radiance to the downwelling spectral irradiance. It can be determined in the field, with either above or in-water radiance and irradiance measurements. The complex optical properties of the North-East Aegean Sea, including radiance and irradiance, were studied during the AegeanMarTech project. Chlorophyll concentration estimates were derived from simultaneous above and in-water radiometric measurements. These were validated against chlorophyll concentration field data and compared against concurrent MODIS data from which chlorophyll was derived using two simple empirical algorithms. It was found that the MedOC3 algorithm outperforms the operational OC3M-547 algorithm and produces the least bias when compared against HPLC derived in situ chlorophyll. It is concluded that the greatest uncertainty in the inversion arises due to CDOM absorption below the 488 nm band. The reflectance ratios indicated that there is always an excess of yellow matter present in the study area and the water type could not be characterized optically as `'typical open ocean" Case 1.

  4. Glucose, fructose and sucrose increase the solubility of protein-tannin complexes and at high concentration, glucose and sucrose interfere with bisulphite bleaching of wine pigments.

    PubMed

    Harbertson, James F; Yuan, Chunlong; Mireles, Maria S; Hanlin, Rachel L; Downey, Mark O

    2013-05-01

    Wines were modified with increasing sugar concentrations and decreasing tannin concentrations and analysed by a combination of protein precipitation and bisulphite bleaching. Increasing sugar concentration decreased the precipitation of tannin and protein-precipitable polymeric pigments (PPP). The use of a hydrogen bond disruptor (urea) to reduce protein-tannin and protein-pigment complex formation showed that the effect of sugar concentration occurred by increasing the solubility of the tannin-protein complex, not by interfering with protein-tannin complex formation. By increasing the solubility of pigment-protein complexes, non-protein-precipitable polymeric pigments (nPPP) appeared to increase. There was also an increase in total polymeric pigments at each tannin concentration with increasing glucose and sucrose concentration, indicating that sugar concentration might also affect bisulphite bleaching of wine pigments. While a significant effect of sugar concentration on tannin-protein complex solubility was observed, these effects were greatest at sugar concentrations far in excess of normal wine making conditions. Under normal wine making conditions, sugar concentration will have a negligible effect on protein-precipitable tannin, PPP and nPPP concentrations.

  5. Spectral determination of concentrations of functionally diverse pigments in increasingly complex arctic tundra canopies.

    PubMed

    Boelman, Natalie T; Magney, Troy S; Logan, Barry A; Griffin, Kevin L; Eitel, Jan U H; Greaves, Heather; Prager, Case M; Vierling, Lee A

    2016-09-01

    As the Arctic warms, tundra vegetation is becoming taller and more structurally complex, as tall deciduous shrubs become increasingly dominant. Emerging studies reveal that shrubs exhibit photosynthetic resource partitioning, akin to forests, that may need accounting for in the "big leaf" net ecosystem exchange models. We conducted a lab experiment on sun and shade leaves from S. pulchra shrubs to determine the influence of both constitutive (slowly changing bulk carotenoid and chlorophyll pools) and facultative (rapidly changing xanthophyll cycle) pigment pools on a suite of spectral vegetation indices, to devise a rapid means of estimating within canopy resource partitioning. We found that: (1) the PRI of dark-adapted shade leaves (PRIo) was double that of sun leaves, and that PRIo was sensitive to variation among sun and shade leaves in both xanthophyll cycle pool size (V + A + Z) (r (2) = 0.59) and Chla/b (r (2) = 0.64); (2) A corrected PRI (difference between dark and illuminated leaves, ΔPRI) was more sensitive to variation among sun and shade leaves in changes to the epoxidation state of their xanthophyll cycle pigments (dEPS) (r (2) = 0.78, RMSE = 0.007) compared to the uncorrected PRI of illuminated leaves (PRI) (r (2) = 0.34, RMSE = 0.02); and (3) the SR680 index was correlated with each of (V + A + Z), lutein, bulk carotenoids, (V + A + Z)/(Chla + b), and Chla/b (r (2) range = 0.52-0.69). We suggest that ΔPRI be employed as a proxy for facultative pigment dynamics, and the SR680 for the estimation of constitutive pigment pools. We contribute the first Arctic-specific information on disentangling PRI-pigment relationships, and offer insight into how spectral indices can assess resource partitioning within shrub tundra canopies.

  6. Reversal of apixaban induced alterations in hemostasis by different coagulation factor concentrates: significance of studies in vitro with circulating human blood.

    PubMed

    Escolar, Gines; Fernandez-Gallego, Victor; Arellano-Rodrigo, Eduardo; Roquer, Jaume; Reverter, Joan Carles; Sanz, Victoria Veronica; Molina, Patricia; Lopez-Vilchez, Irene; Diaz-Ricart, Maribel; Galan, Ana Maria

    2013-01-01

    Apixaban is a new oral anticoagulant with a specific inhibitory action on FXa. No information is available on the reversal of the antihemostatic action of apixaban in experimental or clinical settings. We have evaluated the effectiveness of different factor concentrates at reversing modifications of hemostatic mechanisms induced by moderately elevated concentrations of apixaban (200 ng/ml) added in vitro to blood from healthy donors (n = 10). Effects on thrombin generation (TG) and thromboelastometry (TEM) parameters were assessed. Modifications in platelet adhesive, aggregating and procoagulant activities were evaluated in studies with blood circulating through damaged vascular surfaces, at a shear rate of 600 s(-1). The potential of prothrombin complex concentrates (PCCs; 50 IU/kg), activated prothrombin complex concentrates (aPCCs; 75 IU/kg), or activated recombinant factor VII (rFVIIa; 270 μg/kg), at reversing the antihemostatic actions of apixaban, were investigated. Apixaban interfered with TG kinetics. Delayed lag phase, prolonged time to peak and reduced peak values, were improved by the different concentrates, though modifications in TG patterns were diversely affected depending on the activating reagents. Apixaban significantly prolonged clotting times (CTs) in TEM studies. Prolongations in CTs were corrected by the different concentrates with variable efficacies (rFVIIa≥aPCC>PCC). Apixaban significantly reduced fibrin and platelet interactions with damaged vascular surfaces in perfusion studies (p<0.05 and p<0.01, respectively). Impairments in fibrin formation were normalized by the different concentrates. Only rFVIIa significantly restored levels of platelet deposition. Alterations in hemostasis induced by apixaban were variably compensated by the different factor concentrates investigated. However, effects of these concentrates were not homogeneous in all the tests, with PCCs showing more efficacy in TG, and rFVIIa being more effective on TEM

  7. Reversal of Apixaban Induced Alterations in Hemostasis by Different Coagulation Factor Concentrates: Significance of Studies In Vitro with Circulating Human Blood

    PubMed Central

    Arellano-Rodrigo, Eduardo; Roquer, Jaume; Reverter, Joan Carles; Sanz, Victoria Veronica; Molina, Patricia; Lopez-Vilchez, Irene; Diaz-Ricart, Maribel; Galan, Ana Maria

    2013-01-01

    Apixaban is a new oral anticoagulant with a specific inhibitory action on FXa. No information is available on the reversal of the antihemostatic action of apixaban in experimental or clinical settings. We have evaluated the effectiveness of different factor concentrates at reversing modifications of hemostatic mechanisms induced by moderately elevated concentrations of apixaban (200 ng/ml) added in vitro to blood from healthy donors (n = 10). Effects on thrombin generation (TG) and thromboelastometry (TEM) parameters were assessed. Modifications in platelet adhesive, aggregating and procoagulant activities were evaluated in studies with blood circulating through damaged vascular surfaces, at a shear rate of 600 s−1. The potential of prothrombin complex concentrates (PCCs; 50 IU/kg), activated prothrombin complex concentrates (aPCCs; 75 IU/kg), or activated recombinant factor VII (rFVIIa; 270 μg/kg), at reversing the antihemostatic actions of apixaban, were investigated. Apixaban interfered with TG kinetics. Delayed lag phase, prolonged time to peak and reduced peak values, were improved by the different concentrates, though modifications in TG patterns were diversely affected depending on the activating reagents. Apixaban significantly prolonged clotting times (CTs) in TEM studies. Prolongations in CTs were corrected by the different concentrates with variable efficacies (rFVIIa≥aPCC>PCC). Apixaban significantly reduced fibrin and platelet interactions with damaged vascular surfaces in perfusion studies (p<0.05 and p<0.01, respectively). Impairments in fibrin formation were normalized by the different concentrates. Only rFVIIa significantly restored levels of platelet deposition. Alterations in hemostasis induced by apixaban were variably compensated by the different factor concentrates investigated. However, effects of these concentrates were not homogeneous in all the tests, with PCCs showing more efficacy in TG, and rFVIIa being more effective on TEM

  8. Innovative method for the enrichment of high-polarity bioactive molecules present at low concentrations in complex matrices.

    PubMed

    Liu, Qing-Shan; He, Jie; Zhou, Wen-Bin; Gu, Yu-Long; Huang, Huoqiang; Li, Ke-Qin; Yin, Xiao-Ying

    2017-02-01

    Ginsenoside Rg1 is a valuable bioactive molecule but its high polarity and low concentration in complex mixtures makes it a challenge to separate Ginsenoside Rg1 from other saponins with similar structures, resulting in low extraction efficiency. The successful development of effective Rg1 molecularly imprinted polymers that exhibit high selectivity and adsorption may offer an improved method for the enrichment of active compounds. In this work, molecularly imprinted polymers were prepared with two different methods, precipitation polymerization or surface imprinted polymerization. Comparison of the adsorption abilities showed higher adsorption of the surface molecularly imprinted polymers prepared by surface imprinted polymerization, 46.80 mg/g, compared to the 27.74 mg/g observed for the molecularly imprinted polymers prepared by precipitation polymerization. Therefore, for higher adsorption of the highly polar Rg1, surface imprinted polymerization is a superior technique to make Rg1 molecularly imprinted polymers. The prepared surface molecularly imprinted polymers were tested as a solid-phase extraction column to directionally enrich Rg1 and its analogues from ginseng tea and total ginseng extracts. The column with surface molecularly imprinted polymers showed higher enrichment efficiency and better selectivity than a C18 solid-phase extraction column. Overall, a new, innovative method was developed to efficiently enrich high-polarity bioactive molecules present at low concentrations in complex matrices.

  9. Charge carrier effective mass and concentration derived from combination of Seebeck coefficient and Te125 NMR measurements in complex tellurides

    DOE PAGES

    Levin, E. M.

    2016-06-27

    Thermoelectric materials utilize the Seebeck effect to convert heat to electrical energy. The Seebeck coefficient (thermopower), S, depends on the free (mobile) carrier concentration, n, and effective mass, m*, as S ~ m*/n2/3. The carrier concentration in tellurides can be derived from 125Te nuclear magnetic resonance (NMR) spin-lattice relaxation measurements. The NMR spin-lattice relaxation rate, 1/T1, depends on both n and m* as 1/T1~(m*)3/2n (within classical Maxwell-Boltzmann statistics) or as 1/T1~(m*)2n2/3 (within quantum Fermi-Dirac statistics), which challenges the correct determination of the carrier concentration in some materials by NMR. Here it is shown that the combination of the Seebeck coefficientmore » and 125Te NMR spin-lattice relaxation measurements in complex tellurides provides a unique opportunity to derive the carrier effective mass and then to calculate the carrier concentration. This approach was used to study AgxSbxGe50–2xTe50, well-known GeTe-based high-efficiency tellurium-antimony-germanium-silver thermoelectric materials, where the replacement of Ge by [Ag+Sb] results in significant enhancement of the Seebeck coefficient. Thus, values of both m* and n derived using this combination show that the enhancement of thermopower can be attributed primarily to an increase of the carrier effective mass and partially to a decrease of the carrier concentration when the [Ag+Sb] content increases.« less

  10. Synthetic hydrogel mimics of the nuclear pore complex display selectivity dependent on FG-repeat concentration and electrostatics.

    PubMed

    Friedman, Alicia K; Baker, Lane A

    2016-11-28

    Synthetic hydrogels were utilized to explore influence of both charge and phenylalanine-glycine (FG) repeat concentration on translocation of select proteins. Hydrogels studied represent a biomimetic platform of the nuclear pore complex (NPC) found in eukaryotic cells. Polyacrylamide/phenylalanine-serine-phenylalanine-glycine (FSFG) peptide copolymers have previously demonstrated similar selectivity to native NPCs. Entry of a nuclear transport receptor (Impβ) into hydrogels was monitored with fluorescence microscopy and observed to be greater within gels that contained larger concentrations of FG peptide. Low-resolution structural studies of gels demonstrated changes in morphology and porous network dimensions as FG-repeat concentration was varied. Copolymerization of charged acrylates within the polyacrylamide/FSFG matrix was performed to produce charged hydrogels. Enhanced entry of Impβ, which is negatively charged, was observed in positively charged hydrogels, whereas entry was greatly diminished in negatively charged gels. Synthetic NPC mimics provide a useful testbed for further investigation of nucleocytoplasmic transport and may illuminate new routes for biomimetic separations.

  11. Risk of venous thromboembolism and myocardial infarction associated with factor V Leiden and prothrombin mutations and blood type.

    PubMed

    Sode, Birgitte F; Allin, Kristine H; Dahl, Morten; Gyntelberg, Finn; Nordestgaard, Børge G

    2013-03-19

    ABO blood type locus has been reported to be an important genetic determinant of venous and arterial thrombosis in genome-wide association studies. We tested the hypothesis that ABO blood type alone and in combination with mutations in factor V Leiden R506Q and prothrombin G20210A is associated with the risk of venous thromboembolism and myocardial infarction in the general population. We used data from 2 Danish studies that followed members of the general public from 1977 through 2010. We obtained the genotype of 66 001 white participants for ABO blood type, factor V Leiden R506Q and prothrombin G20210A. We calculated hazard ratios (HRs) and population attributable risk. Our main outcome measures were venous thromboembolism and myocardial infarction. The multivariable adjusted HR for venous thromboembolism was 1.4 (95% confidence interval [CI] 1.3-1.5) for non-O blood type (v. O blood type). For the factor V Leiden R506Q mutation, the adjusted HR was 2.2 (95% CI 2.0-2.5) for heterozygous participants and 7.0 (95%CI 4.8-10) for homozygous participants (v. participants without the mutation). For prothrombin G20210A, the adjusted HR was 1.5 (95%CI 1.2-1.9) for heterozygous participants and 11 (95% CI 2.8-44) for homozygous participants (v. participants without the mutation). When we combined ABO blood type and factor V Leiden R506Q or prothrombin G20210A genotype, there was a stepwise increase in the risk of venous thromboembolism (trend, p<0.001). The population attributable risk of venous thromboembolism was 20% for ABO blood type, 10% for factor V Leiden R506Q and 1% for prothrombin G20210A. Multivariable adjusted HRs for myocardial infarction by genotypes did not differ from 1.0. ABO blood type had an additive effect on the risk of venous thromboembolism when combined with factor V Leiden R506Q and prothrombin G20210A mutations; blood type was the most important risk factor for venous thromboembolism in the general population.

  12. Risk of venous thromboembolism and myocardial infarction associated with factor V Leiden and prothrombin mutations and blood type

    PubMed Central

    Sode, Birgitte F.; Allin, Kristine H.; Dahl, Morten; Gyntelberg, Finn; Nordestgaard, Børge G.

    2013-01-01

    Background: ABO blood type locus has been reported to be an important genetic determinant of venous and arterial thrombosis in genome-wide association studies. We tested the hypothesis that ABO blood type alone and in combination with mutations in factor V Leiden R506Q and prothrombin G20210A is associated with the risk of venous thromboembolism and myocardial infarction in the general population. Methods: We used data from 2 Danish studies that followed members of the general public from 1977 through 2010. We obtained the genotype of 66 001 white participants for ABO blood type, factor V Leiden R506Q and prothrombin G20210A. We calculated hazard ratios (HRs) and population attributable risk. Our main outcome measures were venous thromboembolism and myocardial infarction. Results: The multivariable adjusted HR for venous thromboembolism was 1.4 (95% confidence interval [CI] 1.3–1.5) for non-O blood type (v. O blood type). For the factor V Leiden R506Q mutation, the adjusted HR was 2.2 (95% CI 2.0–2.5) for heterozygous participants and 7.0 (95%CI 4.8–10) for homozygous participants (v. participants without the mutation). For prothrombin G20210A, the adjusted HR was 1.5 (95%CI 1.2–1.9) for heterozygous participants and 11 (95% CI 2.8–44) for homozygous participants (v. participants without the mutation). When we combined ABO blood type and factor V Leiden R506Q or prothrombin G20210A genotype, there was a stepwise increase in the risk of venous thromboembolism (trend, p < 0.001). The population attributable risk of venous thromboembolism was 20% for ABO blood type, 10% for factor V Leiden R506Q and 1% for prothrombin G20210A. Multivariable adjusted HRs for myocardial infarction by genotypes did not differ from 1.0. Interpretation: ABO blood type had an additive effect on the risk of venous thromboembolism when combined with factor V Leiden R506Q and prothrombin G20210A mutations; blood type was the most important risk factor for venous thromboembolism in

  13. A complexity measure based method for studying the dependance of 222Rn concentration time series on indoor air temperature and humidity.

    PubMed

    Mihailovic, D T; Udovičić, V; Krmar, M; Arsenić, I

    2014-02-01

    We have suggested a complexity measure based method for studying the dependence of measured (222)Rn concentration time series on indoor air temperature and humidity. This method is based on the Kolmogorov complexity (KL). We have introduced (i) the sequence of the KL, (ii) the Kolmogorov complexity highest value in the sequence (KLM) and (iii) the KL of the product of time series. The noticed loss of the KLM complexity of (222)Rn concentration time series can be attributed to the indoor air humidity that keeps the radon daughters in air.

  14. [Evaluation of the quality of prothrombin time technique in the Basque Country].

    PubMed

    Vacas, M; Lafuente, P J; Aguirrebeitia, M J; Iriarte, J A

    1998-02-01

    The Programme for Quality Assessment in Anticoagulant Therapy, which was started in the Basque Country in 1984, included the manufacturing of a standard human thromboplastin reagent plus periodical quality controls of the prothrombin time. A rabbit thromboplastin reagent was available in 1994; it was called Thromboplastin Bilbao, or TBi, and had to be used as a pattern reagent. Its stability, sensitivity and composition were plotted against the Manchester Reagent, of similar nature and composition. A new phase of quality quality controls was simultaneously started with this new reagent, a group of hospitals of the Autonomous Community taking part in the programme. The aim was to compare this reagent with the others used by the hospitals and to evaluate the variations with regard to the stages previous to the introduction of the human reagent. Nine centres joined the study. Controls were performed every fourth month including plasma from patients under anticoagulant treatment, plus the reference reagents. The partaking centres used their usual reagents and routine procedures, as well as the reference reagents and manual technique. The coefficient of variation (CV) of the INR of anticoagulated plasmas used for these studies when following the centres' own methods and thromboplastins was 9.5 +/- 6.40%, versus 9.94 +/- 1.57% when TBi was used. These results are in accordance with those attained with the previously manufactured human reagent, whose CV was 8.75 +/- 2.19% in the quality assurance methods performed in the period 1984-88. Concurrently with the programme, the reagent was sent as a part of the Spanish Programme for Quality Assessment in Anticoagulant Treatment to the 51 centres taking part in the study. The CV of the INR of the two lyophilized plasmas sent was, respectively, 14.97% and 16.5%. The average value for the healthy subjects was 14.77 seconds, with 8% inter-centres variation when using manual methods. These results suggest that a thromboplastin is

  15. On the value of routine prothrombin time screening in elective neurosurgical procedures.

    PubMed

    Dützmann, Stephan; Gessler, Florian; Marquardt, Gerhard; Seifert, Volker; Senft, Christian

    2012-11-01

    The authors performed a study to evaluate whether preoperative assessment of prothrombin time (PT) is mandatory in patients undergoing routinely planned neurosurgical procedures. The charts of all patients admitted to general wards of the authors' department for routinely planned surgery (excluding trauma and ICU patients) between 2006 and 2010 were retrospectively reviewed. The authors assessed preoperative PT and the clinical courses of all patients, with special consideration for patients receiving coagulation factor substitution. All cases involving hemorrhagic complications were analyzed in detail with regard to pre- and postoperative PT abnormalities. Prothrombin time was expressed as the international normalized ratio, and values greater than 1.28 were regarded as elevated. Clinical courses and PT values of 4310 patients were reviewed. Of these, 33 patients (0.7%) suffered hemorrhagic complications requiring repeat surgery. Thirty-one patients (94%) had a normal PT before the initial operation, while 2 patients had slightly elevated PT values of 1.33 and 1.65, which were anticipated based on the patient's history. In the latter 2 cases, surgery was performed without prior correction of PT. Preoperatively, PT was elevated in 78 patients (1.8%). In 73 (93.6%) of the 78 patients, the PT elevation was expected and explained by each patient's medical history. In only 5 (0.1%) of 4310 patients did we find an unexpected PT elevation (mean 1.53, range 1.37-1.74). All 5 patients underwent surgery without complications, while 2 had received coagulation factor substitution preoperatively, as requested by the surgeon, because of an estimated risk of bleeding complications. None of the 5 patients received coagulation factor substitution postoperatively, and later detailed laboratory studies ruled out single coagulation factor deficiencies. There was no statistically significant association between preoperatively elevated PT levels and the occurrence of hemorrhagic

  16. Dual-Mode Optical Sensing of Histamine at Nanomolar Concentrations in Complex Biological Fluids and Living Cells.

    PubMed

    Dey, Nilanjan; Ali, Asfa; Podder, Santosh; Majumdar, Shamik; Nandi, Dipankar; Bhattacharya, Santanu

    2017-09-04

    An easily synthesized fluorescein-based luminescent dye has been utilized for the dual-mode detection of histamine at nanomolar concentrations at pH 7.0 in water. The specific response to histamine was achieved by imidazole-catalyzed 'imine formation' reaction. The protocol was subsequently applied for the estimation of histamine in complex biological milieu such as human blood serum and urine samples. Furthermore, the dose-dependent cellular uptake of histamine and de novo synthesis (by thapsigargin treatment) was visualized in RAW 264.7, a mouse macrophage cell line. We have also developed portable paper strips for rapid, on-site detection of histamine without involving costly instruments. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Photochemical Reduction of Low Concentrations of CO2 in a Porous Coordination Polymer with a Ruthenium(II)-CO Complex.

    PubMed

    Kajiwara, Takashi; Fujii, Machiko; Tsujimoto, Masahiko; Kobayashi, Katsuaki; Higuchi, Masakazu; Tanaka, Koji; Kitagawa, Susumu

    2016-02-18

    Direct use of low pressures of CO2 as a C1 source without concentration from gas mixtures is of great interest from an energy-saving viewpoint. Porous heterogeneous catalysts containing both adsorption and catalytically active sites are promising candidates for such applications. Here, we report a porous coordination polymer (PCP)-based catalyst, PCP-Ru(II) composite, bearing a Ru(II) -CO complex active for CO2 reduction. The PCP-Ru(II) composite showed improved CO2 adsorption behavior at ambient temperature. In the photochemical reduction of CO2 the PCP-Ru(II) composite produced CO, HCOOH, and H2 . Catalytic activity was comparable with the corresponding homogeneous Ru(II) catalyst and ranks among the highest of known PCP-based catalysts. Furthermore, catalytic activity was maintained even under a 5 % CO2 /Ar gas mixture, revealing a synergistic effect between the adsorption and catalytically active sites within the PCP-Ru(II) composite.

  18. [Recurrent vascular access trombosis associated with the prothrombin mutation G20210A in a adult patient in haemodialysis].

    PubMed

    Quintana, L F; Coll, E; Monteagudo, I; Collado, S; López-Pedret, J; Cases, A

    2005-01-01

    Vascular access-related complications are a frequent cause of morbidity in haemodialysis patients and generate high costs. We present the case of an adult patient with end-stage renal disease and recurrent vascular access thrombosis associated with the prothrombin mutation G20210A and renal graft intolerance. The clinical expression of this heterozygous gene mutation may have been favoured by inflammatory state, frequent in dialysis patients. In this patient, the inflammatory response associated with the renal graft intolerance would have favored the development of recurrent vascular access thrombosis in a adult heterozygous for prothrombin mutation G20210A. In the case of early dysfunction of haemodialysis vascular access and after ruling out technical problems, it is convenient to carry out a screening for thrombophilia.

  19. Omega-O-Acylceramides in Skin Lipid Membranes: Effects of Concentration, Sphingoid Base, and Model Complexity on Microstructure and Permeability.

    PubMed

    Opálka, Lukáš; Kováčik, Andrej; Maixner, Jaroslav; Vávrová, Kateřina

    2016-12-06

    Omega-O-acylceramides (acylCer), a subclass of sphingolipids with an ultralong N-acyl chain (from 20 to 38 carbons, most usually 30 and 32 carbons), are crucial components of the skin permeability barrier. AcylCer are involved in the formation of the long periodicity lamellar phase (LPP, 12-13 nm), which is essential for preventing water loss from the body. Lower levels of acylCer and LPP accompany skin diseases, such as atopic dermatitis, lamellar ichthyosis, and psoriasis. We studied how the concentration and structure of acylCer influence the organization and permeability barrier properties of model lipid membranes. For simple model membranes composed of the sphingosine-containing acylCer (EOS), N-lignoceroyl sphingosine, lignoceric acid, cholesterol (Chol), and cholesteryl sulfate (CholS), the LPP formed at 10% Cer EOS (of the total Cer) and the short periodicity phase disappeared at 30% Cer EOS. Surprisingly, membranes with the LPP had higher permeabilities than the control membrane without acylCer. In the complex models consisting of acylCer (EOS, phytosphingosine EOP, dihydrosphingosine EOdS, or their mixture; at 10% of the total Cer), a six-component Cer mixture, a free fatty acid mixture, cholesterol (Chol), and cholesteryl sulfate (CholS), acylCer decreased the membrane permeability to model permeants (with the strongest effects for acylCer EOP and EOdS) when compared with the permeability of the control membrane without acylCer. However, in the complex model, only a mixture of acylCer EOS, EOdS, and EOP and not the individual acylCer formed both the LPP and orthorhombic chain packing at the 10% level. Thus, the relationships between acylCer, LPP formation, and permeability barrier function are not trivial. Lipid heterogeneity is essential-only the most complex model with nine Cer subclasses mimicked both the organization and permeability of stratum corneum lipid membranes.

  20. Outcome of Patients with Venous Thromboembolism and Factor V Leiden or Prothrombin 20210 Carrier Mutations During the Course of Anticoagulation.

    PubMed

    Tzoran, Inna; Papadakis, Manolis; Brenner, Benjamin; Fidalgo, Ángeles; Rivas, Agustina; Wells, Philip S; Gavín, Olga; Adarraga, María Dolores; Moustafa, Farès; Monreal, Manuel

    2017-04-01

    Individuals with factor V Leiden or prothrombin G20210A mutations are at a higher risk to develop venous thromboembolism. However, the influence of these polymorphisms on patient outcome during anticoagulant therapy has not been consistently explored. We used the Registro Informatizado de Enfermedad TromboEmbólica database to compare rates of venous thromboembolism recurrence and bleeding events occurring during the anticoagulation course in factor V Leiden carriers, prothrombin mutation carriers, and noncarriers. Between March 2001 and December 2015, 10,139 patients underwent thrombophilia testing. Of these, 1384 were factor V Leiden carriers, 1115 were prothrombin mutation carriers, and 7640 were noncarriers. During the anticoagulation course, 160 patients developed recurrent deep vein thrombosis and 94 patients developed pulmonary embolism (16 died); 154 patients had major bleeding (10 died), and 291 patients had nonmajor bleeding. On multivariable analysis, factor V Leiden carriers had a similar rate of venous thromboembolism recurrence (adjusted hazard ratio [HR], 1.16; 95% confidence interval [CI], 0.82-1.64), half the rate of major bleeding (adjusted HR, 0.50; 95% CI, 0.25-0.99) and a nonsignificantly lower rate of nonmajor bleeding (adjusted HR, 0.66; 95% CI, 0.43-1.01) than noncarriers. Prothrombin mutation carriers and noncarriers had a comparable rate of venous thromboembolism recurrence (adjusted HR, 1.00; 95% CI, 0.68-1.48), major bleeding (adjusted HR, 0.75; 95% CI, 0.42-1.34), and nonmajor bleeding events (adjusted HR, 1.10; 95% CI, 0.77-1.57). During the anticoagulation course, factor V Leiden carriers had a similar risk for venous thromboembolism recurrence and half the risk for major bleeding compared with noncarriers. This finding may contribute to decision-making regarding anticoagulation duration in selected factor V Leiden carriers with venous thromboembolism. Copyright © 2017. Published by Elsevier Inc.

  1. Reference materials (RMs) for analysis of the human factor II (prothrombin) gene G20210A mutation.

    PubMed

    Klein, Christoph L; Márki-Zay, János; Corbisier, Philippe; Gancberg, David; Cooper, Susan; Gemmati, Donato; Halbmayer, Walter-Michael; Kitchen, Steve; Melegh, Béla; Neumaier, Michael; Oldenburg, Johannes; Leibundgut, Elisabeth Oppliger; Reitsma, Pieter H; Rieger, Sandra; Schimmel, Heinz G; Spannagl, Michael; Tordai, Attilia; Tosetto, Alberto; Visvikis, Sophie; Zadro, Renata; Mannhalter, Christine

    2005-01-01

    The Scientific Committee of Molecular Biology Techniques (C-MBT) in Clinical Chemistry of the IFCC has initiated a joint project in co-operation with the European Commission, Joint Research Centre, Institute of Reference Materials and Measurements to develop and produce plasmid-type reference materials (RMs) for the analysis of the human prothrombin gene G20210A mutation. Although DNA tests have a high impact on clinical decision-making and the number of tests performed in diagnostic laboratories is high, issues of quality and quality assurance exist, and currently only a few RMs for clinical genetic testing are available. A gene fragment chosen was produced that spans all primer annealing sites published to date. Both the wild-type and mutant alleles of this gene fragment were cloned into a pUC18 plasmid and two plasmid RMs were produced. In addition, a mixture of both plasmids was produced to mimic the heterozygous genotype. The present study describes the performance of these reference materials in a commutability study, in which they were tested by nine different methods in 13 expert laboratories. This series of plasmid RMs are, to the best of our knowledge, the first plasmid-type clinical genetic RMs introduced worldwide.

  2. Takayasu Arteritis With Antiphosphatidylserine/Prothrombin Antibody-Positive Antiphospholipid Syndrome: Case Report and Literature Review.

    PubMed

    Fukui, Shoichi; Hirota, Shogo; Iwamoto, Naoki; Karata, Hiroki; Kawakami, Atsushi

    2015-12-01

    A relationship between Takayasu arteritis (TA) and positive antiphospholipid antibody states has been pointed out, but patients with TA complicated with antiphospholipid antibody syndrome (APS) are rare. Here we report the case of a 17-year-old Japanese man diagnosed with TA based on pulselessness of the left brachial artery, discrepancy of blood pressure between the upper extremities, and arterial wall thickening and narrowing of artery in contrast computed tomography. He was also diagnosed with provisional APS based on a pulmonary infarction without narrowing of the pulmonary artery and positive antiphosphatidylserine/prothrombin antibody. The patient also had concurrent Crohn's disease (CD) based on histopathological findings, which may have been associated with TA. We started high-dose corticosteroid therapy and anticoagulation therapy, and his symptoms including fever, dizziness, chest pain, and lower-right uncomfortable abdomen improved.We reviewed 9 cases of TA with APS including our patient by conducting a PubMed search. Based on past reports, we considered the relationship among TA, APS, and CD.Clinicians should bear in mind that many etiologies can exist in 1 patient, and differential diagnoses are essential.

  3. The International Normalized Ratio of Prothrombin Time in the MELD Score: A Reliable Measure

    PubMed Central

    Kamath, Patrick S.; Kim, W. Ray

    2011-01-01

    The Model for End-stage Liver Disease has been demonstrated to be an excellent predictor of survival in patients with end-stage liver disease. It is derived from the International Normalized Ratio (INR) of prothrombin time, serum creatinine, and serum total bilirubin. The major use of the MELD score is to prioritize allocation of organs for liver transplantation among patients with chronic liver disease. The INR may be incorrect in liver disease because of generic factors, and factors specific to liver disease. In spite of these limitations, virtually every study that has looked at the MELD score as a predictor of survival has demonstrated that the MELD score using the INR with ISI calibrated for patients on warfarin has a ‘c’ statistic of approximately 0.8, indicating excellent discrimination. Thus, although the current method of measuring INR has drawbacks, the conventional INR remains a very viable means of expressing severity of liver disease and thus an integral part of the MELD score. PMID:19150310

  4. How to report results of prothrombin and activated partial thromboplastin times.

    PubMed

    Tripodi, Armando; Lippi, Giuseppe; Plebani, Mario

    2016-02-01

    Prothrombin time (PT) and activated partial thromboplastin time (APTT) are the most widely used tests to investigate coagulation abnormalities. Varied result reporting have been introduced over the years for the two tests, thus making their interpretation rather confusing in different clinical settings. PT results have been reported as clotting time, percentage activity, PT-ratio (patient-to-normal clotting time) and as international normalized ratio (INR). The INR scale has been devised to harmonize results stemming from different thromboplastins from patients on treatment with vitamin K antagonists. Therefore, there are some theoretical and evidence-based considerations that make the INR formally invalid when the test is used to analyze patients in other clinical settings. Unfortunately, this limitation has been frequently overlooked, and the INR has been (and is currently) used as a universal system of results harmonization. The APTT has been historically reported as clotting time or as ratio (patient-to-normal clotting time). In this opinion paper we review the current state-of-the-art for result reporting and attempt to give practical guidance on how PT and APTT should be reported in different clinical conditions for which the tests are requested.

  5. Comparison of Prothrombin Time and Aspartate Aminotransferase in Predicting Hepatotoxicity After Acetaminophen Overdose.

    PubMed

    Levine, Michael; O'Connor, Ayrn D; Padilla-Jones, Angela; Gerkin, Richard D

    2016-03-01

    Despite decades of experience with acetaminophen (APAP) overdoses, it remains unclear whether elevated hepatic transaminases or coagulopathy develop first. Furthermore, comparison of the predictive value of these two variables in determining hepatic toxicity following APAP overdoses has been poorly elucidated. The primary objective of this study is to determine the test characteristics of the aspartate aminotransferase (AST) and the prothrombin time (PT) in patients with APAP toxicity. A retrospective chart review of APAP overdoses treated with IV N-acetylcysteine at a tertiary care referral center was performed. Of the 304 subjects included in the study, 246 with an initial AST less than 1000 were analyzed to determine predictors of hepatic injury, defined as an AST exceeding 1000 IU/L. The initial AST >50 was 79.5 % sensitive and 82.6 % specific for predicting hepatic injury. The corresponding negative and positive predictive values were 95.5 and 46.3 %, respectively. In contrast, an initial abnormal PT had a sensitivity of 82.1 % and a specificity of 63.6 %. The negative and positive predictive values for initial PT were 94.9 and 30.2 %, respectively. Although the two tests performed similarly for predicting a composite endpoint of death or liver transplant, neither was a useful predictor. Initial AST performed better than the initial PT for predicting hepatic injury in this series of patients with APAP overdose.

  6. Incomplete embryonic lethality and fatal neonatal hemorrhage caused by prothrombin deficiency in mice.

    PubMed

    Xue, J; Wu, Q; Westfield, L A; Tuley, E A; Lu, D; Zhang, Q; Shim, K; Zheng, X; Sadler, J E

    1998-06-23

    Deficiency of blood coagulation factor V or tissue factor causes the death of mouse embryos by 10.5 days of gestation, suggesting that part of the blood coagulation system is necessary for development. This function is proposed to require either generation of the serine protease thrombin and cell signaling through protease-activated receptors or an activity of tissue factor that is distinct from blood clotting. We find that murine deficiency of prothrombin clotting factor 2 (Cf2) was associated with the death of approximately 50% of Cf2(-/-) embryos by embryonic day 10.5 (E10.5), and surviving embryos had characteristic defects in yolk sac vasculature. Most of the remaining Cf2(-/-) embryos died by E15.5, but those surviving to E18.5 appeared normal. The rare Cf2(-/-) neonates died of hemorrhage on the first postnatal day. These studies suggest that a part of the blood coagulation system is adapted to perform a developmental function. Other mouse models show that the absence of platelets or of fibrinogen does not cause fetal wastage. Therefore, the role of thrombin in development may be independent of its effects on blood coagulation and instead may involve signal transduction on cells other than platelets.

  7. Prothrombin Loading of Vascular Smooth Muscle Cell-Derived Exosomes Regulates Coagulation and Calcification.

    PubMed

    Kapustin, Alexander N; Schoppet, Michael; Schurgers, Leon J; Reynolds, Joanne L; McNair, Rosamund; Heiss, Alexander; Jahnen-Dechent, Willi; Hackeng, Tilman M; Schlieper, Georg; Harrison, Paul; Shanahan, Catherine M

    2017-03-01

    The drug warfarin blocks carboxylation of vitamin K-dependent proteins and acts as an anticoagulant and an accelerant of vascular calcification. The calcification inhibitor MGP (matrix Gla [carboxyglutamic acid] protein), produced by vascular smooth muscle cells (VSMCs), is a key target of warfarin action in promoting calcification; however, it remains unclear whether proteins in the coagulation cascade also play a role in calcification. Vascular calcification is initiated by exosomes, and proteomic analysis revealed that VSMC exosomes are loaded with Gla-containing coagulation factors: IX and X, PT (prothrombin), and proteins C and S. Tracing of Alexa488-labeled PT showed that exosome loading occurs by direct binding to externalized phosphatidylserine (PS) on the exosomal surface and by endocytosis and recycling via late endosomes/multivesicular bodies. Notably, the PT Gla domain and a synthetic Gla domain peptide inhibited exosome-mediated VSMC calcification by preventing nucleation site formation on the exosomal surface. PT was deposited in the calcified vasculature, and there was a negative correlation between vascular calcification and the levels of circulating PT. In addition, we found that VSMC exosomes induced thrombogenesis in a tissue factor-dependent and PS-dependent manner. Gamma-carboxylated coagulation proteins are potent inhibitors of vascular calcification suggesting warfarin action on these factors also contributes to accelerated calcification in patients receiving this drug. VSMC exosomes link calcification and coagulation acting as novel activators of the extrinsic coagulation pathway and inducers of calcification in the absence of Gla-containing inhibitors. © 2017 American Heart Association, Inc.

  8. [Utility of measuring prothrombin and activated partial thromboplastin times in a community hospital].

    PubMed

    Las Heras, G; Bosch, A; Martín, E; Rovira, M

    1994-06-01

    To prove an excessive use of prothrombin-time (PT) and activated partial thromboplastin time (APTT) in a regional hospital of A-B nivel with 168 beds. All studies of PT and APTT were compiled during one month. In accordance with assistance type (emergency, inpatient or outpatient), the following parameters were analysed: services distribution and assistance type, justification of haemostasis studies, according to the American Medical Association criteria modified for Erban et al., abnormal findings appeared and economical cost study of the tests, according to the justification request. The total number of haemostasis tests performed in that month was 706, with a daily mean of 22.7. Seven hundred and six were PT analysis and 606 APTT. Fifty-six percent were not adequate. This corresponded to 82.5% of the requests in inpatients, 56% of the outpatients and 33.5% of emergency patients. Only 51 analyses were abnormal, that means 7.4% of all studies. From these, 13 were in inpatients (7.64% from the whole of the patients requests), 11 were outpatients (3.52%) and 27 emergencies (12.8%). The economical burden within the month studied amounted up to 629.760 ptas. The number of haemostasis screening tests was excessive. The correction of this inappropriate use could improve the patient assistance and could decrease the cost, without impairing, and perhaps increasing, the assistential quality.

  9. Anti-phospholipid antibodies (aPL) and apoptosis: prothrombin-dependent aPL as a paradigm for phospholipid-dependent interactions with apoptotic cells☆

    PubMed Central

    Rauch, Joyce; D’Agnillo, Paolo; Subang, Rebecca; Levine, Jerrold S.

    2012-01-01

    The natural targets of anti-phospholipid antibodies (aPL) and the stimuli that induce them remain unknown. Apoptotic cells have been proposed as both potential targets and immunogens for anti-phospholipid antibodies. Demonstration of selective recognition by anti-phospholipid antibodies provides support for apoptotic cells as antigenic targets. Here, we summarize data showing that prothrombin (PT) binds to apoptotic, but not viable, cells, and that apoptotic-cell bound prothrombin provides a target for human polyclonal and murine monoclonal lupus anticoagulant (LA) antibodies. We discuss findings for two monoclonal lupus anticoagulant antibodies that have high (antibody 29J3-62) or low (antibody 29I4-24) affinity, respectively, for soluble prothrombin. Despite their very different affinities for soluble prothrombin, both monoclonal antibodies reacted similarly with prothrombin bound to phospholipid or apoptotic cells. Furthermore, both antibodies enhanced the binding of prothrombin to apoptotic cells. We propose that the recognition of apoptotic cells by these prothrombin-dependent monoclonal antibodies provides a paradigm for other anti-phospholipid autoantibodies. 29I4-24 is prototypical of phospholipid-dependent anti-phospholipid antibodies, while 29J3-62 represents a prototype for phospholipid-independent anti-phospholipid antibodies. Proteins such as prothrombin and β2-glycoprotein I (β2GPI) bind to apoptotic cells, thereby enhancing the recognition of apoptotic cells by anti-phospholipid antibodies. Furthermore, anti-phospholipid antibodies potentiate the interaction of these proteins with apoptotic cells. While it is unclear whether apoptotic cells are the inducing stimuli in patients with anti-phospholipid antibodies or even whether anti-phospholipid antibodies interact with apoptotic cells in vivo, it is nonetheless clear that anti-phospholipid antibodies have the potential to affect both the procoagulant activity and the uptake and clearance of

  10. Risk of recurrent venous thrombosis in homozygous carriers and double heterozygous carriers of factor V Leiden and prothrombin G20210A.

    PubMed

    Lijfering, Willem M; Middeldorp, Saskia; Veeger, Nic J G M; Hamulyák, Karly; Prins, Martin H; Büller, Harry R; van der Meer, Jan

    2010-04-20

    Homozygous or double heterozygous factor V Leiden and/or prothrombin G20210A is a rare inherited thrombophilic trait. Whether individuals with this genetic background have an increased risk of recurrent venous thrombosis is uncertain. A case-control design within a large cohort of families with thrombophilia was chosen to calculate the risk of recurrent venous thrombosis in individuals with homozygosity or double heterozygosity of factor V Leiden and/or prothrombin G20210A. Cases were individuals with recurrent venous thrombosis, and controls were those with only 1 venous thrombosis. The cohort consisted of 788 individuals with venous thrombosis; 357 had factor V Leiden, 137 had prothrombin G20210A, 27 had factor V Leiden and/or prothrombin G20210A homozygosity, and 49 had double heterozygosity for both mutations. We identified 325 cases with recurrent venous thrombosis and 463 controls with only 1 venous thrombosis. Compared with noncarriers, crude odds ratio for recurrence was 1.2 (95% confidence interval, 0.9 to 1.6) for heterozygous carriers of factor V Leiden, 0.7 (95% confidence interval, 0.4 to 1.2) for prothrombin G20210A, 1.2 (95% confidence interval, 0.5 to 2.6) for homozygous carriers of factor V Leiden and/or prothrombin G20210A, and 1.0 (95% confidence interval, 0.6 to 1.9) for double heterozygotes of both mutations. Adjustments for age, sex, family status, first event type, and concomitance of natural anticoagulant deficiencies did not alter the risk estimates. In this study, individuals with homozygous factor V Leiden and/or homozygous prothrombin G20210A or double heterozygous carriers of factor V Leiden and prothrombin G20210A did not have a high risk of recurrent venous thrombosis.

  11. The risk of early mortality of polytrauma patients associated to ISS, NISS, APACHE II values and prothrombin time.

    PubMed

    Mica, Ladislav; Rufibach, Kaspar; Keel, Marius; Trentz, Otmar

    2013-01-01

    The early hemodynamic normalization of polytrauma patients may lead to better survival outcomes. The aim of this study was to assess the diagnostic quality of trauma and physiological scores from widely used scoring systems in polytrauma patients. In total, 770 patients with ISS > 16 who were admitted to a trauma center within the first 24 hours after injury were included in this retrospective study. The patients were subdivided into three groups: those who died on the day of admission, those who died within the first three days, and those who survived for longer than three days. ISS, NISS, APACHE II score, and prothrombin time were recorded at admission. The descriptive statistics for early death in polytrauma patients who died on the day of admission, 1-3 days after admission, and > 3 days after admission were: ISS of 41.0, 34.0, and 29.0, respectively; NISS of 50.0, 50.0, and 41.0, respectively; APACHE II score of 30.0, 25.0, and 15.0, respectively; and prothrombin time of 37.0%, 56.0%, and 84%, respectively. These data indicate that prothrombin time (AUC: 0.89) and APACHE II (AUC: 0.88) have the greatest prognostic utility for early death. The estimated densities of the scores may suggest a direction for resuscitative procedures in polytrauma patients. "Retrospektive Analysen in der Chirurgischen Intensivmedizin"StV01-2008.

  12. Complexity.

    PubMed

    Gómez-Hernández, J Jaime

    2006-01-01

    It is difficult to define complexity in modeling. Complexity is often associated with uncertainty since modeling uncertainty is an intrinsically difficult task. However, modeling uncertainty does not require, necessarily, complex models, in the sense of a model requiring an unmanageable number of degrees of freedom to characterize the aquifer. The relationship between complexity, uncertainty, heterogeneity, and stochastic modeling is not simple. Aquifer models should be able to quantify the uncertainty of their predictions, which can be done using stochastic models that produce heterogeneous realizations of aquifer parameters. This is the type of complexity addressed in this article.

  13. Modeling the human prothrombinase complex components

    NASA Astrophysics Data System (ADS)

    Orban, Tivadar

    Thrombin generation is the culminating stage of the blood coagulation process. Thrombin is obtained from prothrombin (the substrate) in a reaction catalyzed by the prothrombinase complex (the enzyme). The prothrombinase complex is composed of factor Xa (the enzyme), factor Va (the cofactor) associated in the presence of calcium ions on a negatively charged cell membrane. Factor Xa, alone, can activate prothrombin to thrombin; however, the rate of conversion is not physiologically relevant for survival. Incorporation of factor Va into prothrombinase accelerates the rate of prothrombinase activity by 300,000-fold, and provides the physiological pathway of thrombin generation. The long-term goal of the current proposal is to provide the necessary support for the advancing of studies to design potential drug candidates that may be used to avoid development of deep venous thrombosis in high-risk patients. The short-term goals of the present proposal are to (1) to propose a model of a mixed asymmetric phospholipid bilayer, (2) expand the incomplete model of human coagulation factor Va and study its interaction with the phospholipid bilayer, (3) to create a homology model of prothrombin (4) to study the dynamics of interaction between prothrombin and the phospholipid bilayer.

  14. Blood alcohol concentration at 0.06 and 0.10% causes a complex multifaceted deterioration of body movement control.

    PubMed

    Modig, Fredrik; Fransson, Per-Anders; Magnusson, Måns; Patel, Mitesh

    2012-02-01

    Alcohol-related falls are recognized as a major contributor to the occurrence of traumatic brain injury. The control of upright standing balance is complex and composes of contributions from several partly independent mechanisms such as appropriate information from multiple sensory systems and correct feedback and feed forward movement control. Analysis of multisegmented body movement offers a rarely used option for detecting the fine motor problems associated with alcohol intoxication. The study aims were to investigate whether (1) alcohol intoxication at 0.06 and 0.10% blood alcohol concentration (BAC) affected the body movements under unperturbed and perturbed standing; and (2) alcohol affected the ability for sensorimotor adaptation. Body movements were recorded in 25 participants (13 women and 12 men, mean age 25.1 years) at five locations (ankle, knee, hip, shoulder, and head) during quiet standing and during balance perturbations from pseudorandom pulses of calf muscle vibration over 200s with eyes closed or open. Tests were performed at 0.00, 0.06, and 0.10% BAC. The study revealed several significant findings: (1) an alcohol dose-specific effect; (2) a direction-specific stability decrease from alcohol intoxication; (3) a movement pattern change related to the level of alcohol intoxication during unperturbed standing and perturbed standing; (4) a sensorimotor adaptation deterioration with increased alcohol intoxication; and (5) that vision provided a weaker contribution to postural control during alcohol intoxication. Hence, alcohol intoxication at 0.06 and 0.10% BAC causes a complex multifaceted deterioration of human postural control. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Dynamics of metal-humate complexation equilibria as revealed by isotope exchange studies - a matter of concentration and time

    NASA Astrophysics Data System (ADS)

    Lippold, Holger; Eidner, Sascha; Kumke, Michael U.; Lippmann-Pipke, Johanna

    2017-01-01

    Complexation with dissolved humic matter can be crucial in controlling the mobility of toxic or radioactive contaminant metals. For speciation and transport modelling, a dynamic equilibrium process is commonly assumed, where association and dissociation run permanently. This is, however, questionable in view of reported observations of a growing resistance to dissociation over time. In this study, the isotope exchange principle was employed to gain direct insight into the dynamics of the complexation equilibrium, including kinetic inertisation phenomena. Terbium(III), an analogue of trivalent actinides, was used as a representative of higher-valent metals. Isotherms of binding to (flocculated) humic acid, determined by means of 160Tb as a radiotracer, were found to be identical regardless of whether the radioisotope was introduced together with the bulk of stable 159Tb or subsequently after pre-equilibration for up to 3 months. Consequently, there is a permanent exchange of free and humic-bound Tb since all available binding sites are occupied in the plateau region of the isotherm. The existence of a dynamic equilibrium was thus evidenced. There was no indication of an inertisation under these experimental conditions. If the small amount of 160Tb was introduced prior to saturation with 159Tb, the expected partial desorption of 160Tb occurred at much lower rates than observed for the equilibration process in the reverse procedure. In addition, the rates decreased with time of pre-equilibration. Inertisation phenomena are thus confined to the stronger sites of humic molecules (occupied at low metal concentrations). Analysing the time-dependent course of isotope exchange according to first-order kinetics indicated that up to 3 years are needed to attain equilibrium. Since, however, metal-humic interaction remains reversible, exchange of metals between humic carriers and mineral surfaces cannot be neglected on the long time scale to be considered in predictive

  16. New procyanidin B3-human salivary protein complexes by mass spectrometry. Effect of salivary protein profile, tannin concentration, and time stability.

    PubMed

    Perez-Gregorio, Maria Rosa; Mateus, Nuno; De Freitas, Victor

    2014-10-15

    Several factors could influence the tannin-protein interaction such as the human salivary protein profile, the tannin tested, and the tannin/protein ratio. The goal of this study aims to study the effect of different salivas (A, B, and C) and different tannin concentrations (0.5 and 1 mg/mL) on the interaction process as well as the complex's stability over time. This study is focused on the identification of new procyanidin B3-human salivary protein complexes. Thus, 48 major B3-human salivary protein aggregates were identified regardless of the saliva and tannin concentration tested. A higher number of aggregates was found at lower tannin concentration. Moreover, the number of protein moieties involved in the aggregation process was higher when the tannin concentration was also higher. The selectivity of the different groups of proteins to bind tannin was also confirmed. It was also verified that the B3-human salivary protein complexes formed evolved over time.

  17. The introduction of anti-phosphatidylserine/prothrombin autoantibodies in the laboratory diagnostic process of anti-phospholipid antibody syndrome: 6 months of observation.

    PubMed

    Fabris, Martina; Giacomello, Roberta; Poz, Alessandra; Pantarotto, Lisa; Tanzi, Nicolanna; Curcio, Francesco; Tonutti, Elio

    2014-09-01

    To evaluate the impact of the introduction of the anti-phosphatidylserine/prothrombin autoantibodies (aPS/PT) in the laboratory diagnostic process of anti-phospholipid antibody syndrome (APS). Four hundred and twenty-one patients (71.5 % females; 53 ± 15 years) presenting a medical prescription for aPS/PT antibodies were consecutively enrolled in the study from March 2013 to August 2013. During the same period, aPS/PT were additionally investigated in a selected series of 62 patients characterized by difficult lupus anticoagulant (LA) tests interpretation and in a retrospective series of 52 LA positive cases with available data about anti-prothrombin (aPT) antibodies. The aPS/PT antibodies, as well as the anti-cardiolipin (aCL), the anti-β2 glycoprotein I (aβ2GPI) and the aPT antibodies were analyzed by ELISA. LA was tested according to the recommended criteria, performing both the screen and the confirm steps. Overall, aPS/PT IgM positive (>30 U/ml) and/or IgG frankly positive (>40 U/ml) antibodies were found in 49/421 (11.6 %) cases. Among the LA positive patients, we found 56.1 % aPS/PT positive versus 31.7 % aCL and/or aβ2GPI positive cases, with limited (17.1 %) simultaneous positivity. The PS/PT complex resulted the newly recognized specificity in about 27 % of patients recruited from the subset with difficult LA test interpretation. Compared to aPT antibodies, the aPS/PT antibodies displayed a much higher sensitivity (55.8 versus 15.4 %) in LA positive patients. The introduction of aPS/PT antibodies in the diagnostic process of APS is highly recommended, since they disclose a notable diagnostic performance and a high correlation with LA activity, such that they can be a viable alternative.

  18. Moraxella catarrhalis Macrolide-Resistant Isolates Are Highly Concentrated in Two MLST Clonal Complexes -CCN10 and CC363

    PubMed Central

    Liu, Ya-Li; Xiao, Meng; Cheng, Jing-Wei; Xu, He-Ping; Xu, Zhi-Peng; Ye, Sha; Zhang, Wen-Juan; Kudinha, Timothy; Kong, Fanrong; Xu, Ying-Chun

    2017-01-01

    To gain some insights into the molecular evolution of Moraxella catarrhalis macrolide resistance, PCR and sequencing analysis of the 23S rRNA gene, copB typing and multilocus sequence typing (MLST) were performed on 181 M. catarrhalis isolates. The isolates were obtained from children (n = 47) and adults (n = 134) presenting with respiratory disease in the years 2010–2014. Macrolide resistance was highly age-related, and nucleotide position alterations at A2330T could be detected in all macrolide-resistant isolates. copB 0 and copB NT (non-typable) were only found in macrolide-susceptible isolates from adults. Furthermore, copB I/III was the main type in adult or macrolide-susceptible isolates, while copB II was the most common type in children or macrolide-resistant isolates. Twenty-two different MLST clusters (sharing 7 of the 8 identical loci) were detected and only four likely primary founders (ST224, ST363, STN08, and STN10) which belong to clonal complex (CC) 224, CC363, CCN08, and CCN10, were detected, respectively. Macrolide-resistant M. catarrhalis isolates were highly concentrated in two CCs (CCN10 and CC363), which indicates some potential evolutionary advantage or co-evolution to some extent. However, further studies are needed to fully elucidate the evolution of CCN10 and CC363 in macrolide resistance. PMID:28239374

  19. Landscape variability of the stable carbon isotope composition of soil CO2 concentrations and flux in complex terrain

    NASA Astrophysics Data System (ADS)

    Riveros-Iregui, Diego; Liang, Liyin; Risk, David

    2015-04-01

    Stable isotopes are commonly used to understand how physical and biological processes mediate the exchange of carbon between terrestrial ecosystems and the atmosphere. Numerous studies have described fundamental relationships between environmental variables, the carbon isotopic composition (δ13C) of recently assimilated sugars in plants, litter, soil carbon, or recently respired CO2. However, studies that examine the landscape scale variability of the 13C content of forest soils are lacking. We report on measurements of the carbon isotopic composition of soil CO2 concentrations (δ13CC) and flux (δ13CJ) across a subalpine forest of the northern Rocky Mountains of Montana, United States. Our analysis demonstrates that soil moisture and the lateral redistribution of soil water are strong predictors of the spatial variability of both δ13CC and δ13CJ at the watershed scale. Our analysis suggests that there are concomitant yet independent effects of soil water on physical (i.e., soil gas diffusivity) and biological (i.e., photosynthetic activity) processes that mediate the 13C composition of forest soils. We show systematic spatial variability in the δ13C of forest soils at the landscape scale that can be useful to accurately predict and model land-atmosphere CO2 exchange over complex terrain.

  20. Moraxella catarrhalis Macrolide-Resistant Isolates Are Highly Concentrated in Two MLST Clonal Complexes -CCN10 and CC363.

    PubMed

    Liu, Ya-Li; Xiao, Meng; Cheng, Jing-Wei; Xu, He-Ping; Xu, Zhi-Peng; Ye, Sha; Zhang, Wen-Juan; Kudinha, Timothy; Kong, Fanrong; Xu, Ying-Chun

    2017-01-01

    To gain some insights into the molecular evolution of Moraxella catarrhalis macrolide resistance, PCR and sequencing analysis of the 23S rRNA gene, copB typing and multilocus sequence typing (MLST) were performed on 181 M. catarrhalis isolates. The isolates were obtained from children (n = 47) and adults (n = 134) presenting with respiratory disease in the years 2010-2014. Macrolide resistance was highly age-related, and nucleotide position alterations at A2330T could be detected in all macrolide-resistant isolates. copB 0 and copB NT (non-typable) were only found in macrolide-susceptible isolates from adults. Furthermore, copB I/III was the main type in adult or macrolide-susceptible isolates, while copB II was the most common type in children or macrolide-resistant isolates. Twenty-two different MLST clusters (sharing 7 of the 8 identical loci) were detected and only four likely primary founders (ST224, ST363, STN08, and STN10) which belong to clonal complex (CC) 224, CC363, CCN08, and CCN10, were detected, respectively. Macrolide-resistant M. catarrhalis isolates were highly concentrated in two CCs (CCN10 and CC363), which indicates some potential evolutionary advantage or co-evolution to some extent. However, further studies are needed to fully elucidate the evolution of CCN10 and CC363 in macrolide resistance.

  1. Fiber optic immunosensor for cross-linked fibrin concentration

    NASA Astrophysics Data System (ADS)

    Moskowitz, Samuel E.

    2000-08-01

    Working with calcium ions in the blood, platelets produce thromboplastin which transforms prothrombin into thrombin. Removing peptides, thrombin changes fibrinogen into fibrin. Cross-linked insoluble fibrin polymers are solubilized by enzyme plasmin found in blood plasma. Resulting D-dimers are elevated in patients with intravascular coagulation, deep venous thrombosis, pulmonary embolism, myocardial infarction, multiple trauma, cancer, impaired renal and liver functions, and sepsis. Consisting principally of a NIR 780 nm GaAlAs laser diode and a 800 nm avalanche photodiode (APD), the fiber-optic immunosensor can determined D-dimer concentration to levels <0.1 ng/ml. A capture monoclonal antibody to the antigen soluble cross-linked fibrin is employed. Immobilized at the tip of an optical fiber by avidin-biotin, the captured antigen is detected by a second antibody which is labeled with NN 382 fluorescent dye. An evanescent wave traveling on an excitation optical fiber excites the antibody-antigen fluorophore complex. Concentration of cross-linked fibrin is directly proportional to the APD measured intensity of fluorescence. NIR fluorescence has advantages of low background interference, short fluorescence lifetime, and large difference between excitation and emission peaks. Competitive ELISA test for D-dimer concentration requires trained personnel performing a time consuming operation.

  2. Restoration of Normal Prothrombin Time/International Normalized Ratio With Fresh Frozen Plasma in Hypocoagulable Patients.

    PubMed

    Only, Arthur J; DeChristopher, Phillip J; Iqal, Omer; Fareed, Jawed

    2016-01-01

    Fresh frozen plasma (FFP) is an effective reversal agent for hypocoagulable patients. Its proven efficacy continues to prompt its usage as both a prophylactic and a therapeutic therapy. Although published guidelines encouraging the appropriate administration of FFP exist, overutilization continues. The purpose of these ex vivo studies was to determine the effects of succeeding volumes of FFP supplementation on hypocoagulable plasma prothrombin time/international normalized ratio (PT/INR). By analyzing the decline in PT/INR with varying volumes of FFP, a minimal required volume of FFP could be identified representing the optimal volume to administer while still providing therapeutic effect. A total of 497 plasma samples were screened for elevated PT/INR values and 50 samples were selected for inclusion in this experiment. The initial PTs/INRs ranged from 12.5 to 43.4 seconds/1.42 to 4.91. Subsequent declines in PT/INR values were analyzed following addition of 50, 100, and 150 µL of FFP to a fixed volume of 250 µL of plasma (26.4 ± 5.318 seconds/2.99 ± 0.603, 13.3 ± 1.077 seconds/1.51 ± 0.122, 11.2 ± 0.712 seconds/1.27 ± 0.081, and 10.3 ± 0.533 seconds/1.16 ± 0.06, respectively). A nonlinear relationship between decline in INR values and percentage of FFP supplementation was demonstrated. The greatest effect on INR was obtained after supplementation with 50 µL (49%). Doubling and tripling the volume of FFP lead to significantly lower declines in INR (16% and 8%, respectively). Analysis of variance indicated a statistical significance with subsequent volume supplementation of FFP, but marginal clinical benefits exist between the PTs/INRs obtainable with increased FFP volume administration. © The Author(s) 2014.

  3. Meta-analysis of factor V Leiden and prothrombin G20210A polymorphism in migraine.

    PubMed

    Lippi, Giuseppe; Mattiuzzi, Camilla; Cervellin, Gianfranco

    2015-01-01

    Migraine is a frequent and disabling condition, which exhibits a substantial genetic background and is frequently associated with abnormalities of primary and secondary hemostasis. We performed a systematic literature search and a meta-analysis of available data about the potential associations between migraine and factor V (FV) Leiden or prothrombin (FII) G20210A gene polymorphism. The final number of studies included was 15 (all cross-sectional) about migraine and FV Leiden, and 12 (all cross-sectional) about migraine and FII G20210A polymorphism, with broad inter-study heterogeneity (I², 82 and 85%). The cumulative prevalence of the FV 1691A allele was found to be similar between cases (n = 1450; 4.9%) and controls (n = 3468; 4.7%; P = 0.74). The cumulative prevalence of the FII 20210A allele was also found to be similar between cases (n = 1226; 4.2%) and controls (n = 3144; 4.5%; P = 0.59). Nevertheless, sub-analysis of studies in adults and children revealed that both polymorphisms were not associated with migraine in adults, but FV Leiden and the FII 20210A allele were approximately two-fold more prevalent in children with migraine than in those without. In conclusion, despite migraine exhibits a clear neurovascular origin and is frequently associated with thrombotic disorders, isolate thrombophilic mutations seem to play a negligible pathogenetic role in this condition in adults, whereas the increased prevalence of FV Leiden and the FII 20210A allele in children with migraine deserves further scrutiny.

  4. Effects of Tramadol Coadministration on Prothrombin Time-International Normalized Ratio in Patients Receiving Warfarin.

    PubMed

    Hosono, Tomomi; Kondo, Aiko; Kambayashi, Yasuyuki; Homma, Masato

    2017-01-01

     Several case studies have reported a possible drug interaction between warfarin and tramadol where tramadol coadministration enhanced the antithrombotic effects of warfarin. To assess this drug interaction, changes in prothrombin time-international normalized ratio (PT-INR) before and after tramadol coadministration were investigated in patients receiving warfarin. For this study, we examined 54 patients (male/female: 22/32, 68.4±12.7 years) who were being treated with warfarin for deep vein thrombosis, atrial fibrillation, arteriosclerosis obliterans, congestive heart failure, and other vascular diseases. Significant increases in PT-INR were observed 9.5 (1-118) d after coadministration of tramadol (1.81±0.56 vs. 2.47±1.10, p<0.01). Twenty-eight patients (PT-INR increased group) with PT-INR elevation of greater than 0.5 or dose reduction of warfarin after coadministration of tramadol were compared with other groups of patients to find drug interaction risk factors. Logistic regression analysis revealed that lower levels of albumin (3.5 g/dL or less) [odds ratio (OR) 22.1; 95%CI 2.9-169.9]; lower eGFR (50 mL/min or less) (OR 7.7; 95%CI 1.4-42.0); and PT-INR before tramadol coadministration (OR 38.2; 95%CI 3.7-397.6) were characteristic of the PT-INR increased group. These results suggest that tramadol coadministration enhanced the antithrombotic effects of warfarin in patients with higher PT-INR, lower albumin levels and decreased renal function as the risk factors for this drug interaction.

  5. A Systematic Review of Des-γ-Carboxy Prothrombin for the Diagnosis of Primary Hepatocellular Carcinoma

    PubMed Central

    De, Ji; Shen, Yi; Qin, Jinyu; Feng, Li; Wang, Yiping; Yang, Li

    2016-01-01

    Abstract Determining the serum des-γ-carboxy-prothrombin (DCP) level is of great importance for the diagnosis of primary hepatocellular carcinoma (PHC). Although several studies have investigated the accuracy of diagnostic DCP tests for PHC, the results have been inconsistent. The aim of this study was to systematically evaluate DCP as a diagnostic standard for PHC. Several databases, including PubMed, EMBASE, MEDLINE (Ovid), the Chinese National Knowledge Infrastructure (CNKI), the VIP Database for Chinese Technical Periodicals (VIP), WanFang Data, and the China Biological Medicine Database (CBM), were searched from the date of database inception until July 1, 2015 to collect published international and domestic studies of DCP in the diagnosis of PHC. Two investigators screened the literature according to the inclusion and exclusion criteria, extracted the data, and assessed the methodological quality of the included studies. A total of 38 studies involving 11,124 cases were included (5298 cases in the PHC group and 5826 cases in the control group). A meta-analysis was then performed using Meta-Disc 1.4 and RevMan 5.2 software. The overall sensitivity, specificity, positive likelihood ratio (+LR), and negative likelihood ratio (−LR) of DCP for the detection of PHC were 0.66 (95% confidence interval [CI]: 0.65–0.68), 0.88 (95% CI: 0.87–0.90), 7.13 (95% CI: 5.73–8.87), and 0.33 (95% CI: 0.29–0.38), respectively. The area under the curve (AUC) of the summary receiver-operating characteristic curve (SROC) was 0.9002. In conclusion, DCP has moderate diagnostic utility for PHC. Owing to the heterogeneity and limitations of the included studies, the above conclusion requires further support from additional high-quality studies. PMID:27124038

  6. European Concerted Action on Anticoagulation (ECAA). An assessment of lyophilised plasmas for ISI calibration of CoaguChek and TAS whole blood prothrombin time monitors

    PubMed Central

    Poller, L; Keown, M; Chauhan, N; van den Besselaar, A M H P; Tripodi, A; Shiach, C; Jespersen, J

    2003-01-01

    Aims: The recommended method for the international sensitivity index (ISI) calibration of whole blood point of care testing (POCT) prothrombin time (PT) systems was originally described by Tripodi et al in 1993 but is too complex and demanding. The present European Concerted Action on Anticoagulation (ECAA) study aimed to assess the reliability of simpler ISI calibration using lyophilised plasma samples. Methods: ISI calibrations using three different types of ECAA lyophilised plasma samples (artificially depleted, individual, and pooled coumarin) were compared with whole blood calibrations on CoaguChek Mini and TAS PT-NC POCT monitors at 10 centres. Results: With CoaguChek Mini systems, lyophilised coumarin plasma samples (both single donation and pooled) gave ISI and international normalised ratio (INR) values comparable to whole blood. With artificially depleted plasma, ISI and INR values were too high. With TAS PT-NC systems, all three types of lyophilised plasma samples gave inaccurate ISI and unreliable INR results, similar to previous ECAA findings with fresh plasma calibrations. Conclusions: With CoaguChek Mini systems, ISI calibration can be simplified by the use of ECAA lyophilised plasma samples from coumarin treated patients. Further study is needed to devise a simpler calibration method for the TAS PT-NC system. PMID:12560389

  7. Prognostic Value of Prothrombin Time International Normalized Ratio in Acute Decompensated Heart Failure - A Combined Marker of Hepatic Insufficiency and Hemostatic Abnormality.

    PubMed

    Okada, Atsushi; Sugano, Yasuo; Nagai, Toshiyuki; Takashio, Seiji; Honda, Satoshi; Asaumi, Yasuhide; Aiba, Takeshi; Noguchi, Teruo; Kusano, Kengo F; Ogawa, Hisao; Yasuda, Satoshi; Anzai, Toshihisa

    2016-01-01

    There are limited studies regarding the prognostic value of coagulation abnormalities in heart failure patients. The clinical significance of prothrombin time international normalized ratio (INR), a widely accepted marker assessing coagulation abnormalities, in acute decompensated heart failure (ADHF) remains unclear. Among 561 consecutive patients admitted for ADHF, INR was assessed in 294 patients without prior anticoagulation therapy, acute coronary syndrome, liver disease, or overt disseminated intravascular coagulation. Increased INR on admission was positively associated with increased levels of thrombin-antithrombin complex, C-reactive protein, total bilirubin, γ-glutamyl transpeptidase, inferior vena cava diameter, tricuspid regurgitation severity, markers of neurohormonal activation, and also negatively associated with decreased albumin, cholinesterase, and total cholesterol. In contrast, there was no significant association with left ventricular ejection fraction, serum sodium or blood urea nitrogen. Multivariate analysis showed that increased INR was independently associated with increased all-cause mortality (hazard ratio 1.89 per 0.1 increase, 95% confidence interval 1.14-3.13, P=0.013) during the median follow up of 284 days. Increased INR also had a higher prognostic value compared to risk score models including the Model for End-Stage Liver Disease (MELD) score or the MELD excluding INR (MELD-XI) score. Increased INR is an independent predictor of all-cause mortality in ADHF patients without anticoagulation, reflecting coagulation abnormalities and hepatic insufficiency, possibly through systemic inflammation, neurohormonal activation and venous congestion.

  8. Clinical characteristics of patients with factor V Leiden or prothrombin G20210A and a first episode of venous thromboembolism. Findings from the RIETE Registry.

    PubMed

    Gadelha, Telma; Roldán, Vanessa; Lecumberri, Ramón; Trujillo-Santos, Javier; del Campo, Raquel; Poggio, Renzo; Monreal, Manuel

    2010-10-01

    The clinical characteristics of patients with factor V Leiden or prothrombin G20210A presenting with a first episode of venous thromboembolism (VTE) have not been thoroughly studied. RIETE is an ongoing registry of consecutive patients with acute VTE. We compared the clinical characteristics of patients with factor V Leiden, prothrombin G20210A, or no thrombophilia, at presentation with a first episode of VTE. As of May 2009, 22428 patients had been enrolled with a first episode of VTE. Of these, 345 had factor V Leiden, 261 had prothrombin G20210A, and 2399 tested negative. Sixty-two percent of the VTE episodes in women with factor V Leiden or prothrombin G20210A (40% in men) were associated with an acquired risk factor. Among women, pregnancy or contraceptive use accounted for 63% and 67% of such risk factors. Patients with factor V Leiden presented with pulmonary embolism (PE) less likely than those with prothrombin G20210A (31% vs. 51%; p<0.001) or with negative testing (31% vs. 45%, p<0.001). In addition, PE patients with Factor V Leiden presented with hypoxaemia (Sat O(2) levels<90%) less likely than those with prothrombin G20210A (4.5% vs. 17%; p<0.001) or with no thrombophilia (4.5% vs. 20%; p<0.001). Most VTE episodes in women (not men) with factor V Leiden or prothrombin G20210A were associated with an acquired risk factor (mostly pregnancy or contraceptive use). Only 4.5% of patients with factor V Leiden presenting with acute PE had hypoxaemia. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Primary thrombophilia in Mexico. II. Factor V G1691A (Leiden), prothrombin G20210A, and methylenetetrahydrofolate reductase C677T polymorphism in thrombophilic Mexican mestizos.

    PubMed

    Ruiz-Argüelles, G J; Garcés-Eisele, J; Reyes-Núñez, V; Ramírez-Cisneros, F J

    2001-01-01

    We have shown that in Mexican mestizo patients with clinical features of primary thrombophilia, 39% have activated protein C resistance phenotype, 5% protein C deficiency, and 2% protein S deficiency. In the present study, in a group of 37 thrombophilic Mexicans and 50 normal controls, we assessed the factor V G1691A (Leiden), the prothrombin G20210A, and the methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphisms. Four patients were found to be heterozygous for factor V Leiden, 5 heterozygous for the prothrombin 20210, 16 heterozygous, and 6 homozygous for the MTHFR 677. There were four individuals with co-segregation of alleles: two heterozygotes for the factor V Leiden/prothrombin 20210, one heterozygote for prothrombin 20210/MTHFR 677, and one heterozygote for prothrombin 20210/homozygote for MTHFR 677. For factor V Leiden, prothrombin 20210, and MTHFR 677 mutations, the allele frequencies were respectively 1% (+/-0.2%, alpha = 0.05), <1% and 51% (+/-5%, alpha = 0.05), with calculated relative risks for thrombosis of 5.94 (P = 0.08), >7.66 (P < 0.05), and 0.44 (P NS), respectively. In Mexican mestizo thrombophilic patients, the low prevalence of the factor V Leiden mutation (10.8%) and the high prevalence of the prothrombin 20210 mutation (13.5%) contrast with those identified in Caucasian thrombophilic patients (21% and 6%, respectively; P < 0.01). On the other hand, the high prevalence of the MTHFR 677 mutation gene both in normal controls (78%) and thrombophilic patients (61%) does not support a role of this mutation in the thrombogenesis of Mexican mestizo patients.

  10. Online transient isotachophoresis concentration by the pseudo-terminating electrolyte buffer for the separation of DNA-aptamer and its thrombin complex in poly(methyl methacrylate) microchip.

    PubMed

    Wang, Jun; Zhang, Yong; Okamoto, Yukihiro; Kaji, Noritada; Tokeshi, Manabu; Baba, Yoshinobu

    2011-03-21

    Online automatic transient isotachophoresis concentration of DNA-aptamer and its thrombin complex by using one kind of pseudo-terminating electrolyte buffer in a cross-channel poly(methyl methacrylate) microchip is reported. Sample injection, transient concentration and separation were done continuously and controlled by a sequential voltage switching program, time-consuming steps and complicated chip design were not required. Peak resolution between DNA-aptamer and its thrombin complex was influenced by this novel pseudo-terminating electrolyte buffer, which was prepared by the addition of chemical component with slow mobility into the same buffer as leading electrolyte buffer. 1100-fold signal enhancement of thrombin complex was achieved by this transient isotachophoresis on a standard cross-form microchip. The concentration effect or standing time of transient isotachophoresis was proved to be influenced by the concentration of leading electrolyte ion and the concentration of pseudo-terminating electrolyte buffer ion (glycine). The transient concentration was followed by on-chip nondenaturing gel electrophoresis in methylcellulose solution for the size-based separation. The detection limit, taken as the lowest thrombin concentration at threefold S/N, was determined to be 0.5 amol in mass by this method. This journal is © The Royal Society of Chemistry 2011

  11. Exposure of Phytopathogenic Xanthomonas spp. to Lethal Concentrations of Multiple Oxidants Affects Bacterial Survival in a Complex Manner

    PubMed Central

    Sriprang, Rutchadaporn; Vattanaviboon, Paiboon; Mongkolsuk, Skorn

    2000-01-01

    During plant-microbe interactions and in the environment, Xanthomonas campestris pv. phaseoli is likely to be exposed to high concentrations of multiple oxidants. Here, we show that simultaneous exposures of the bacteria to multiple oxidants affects cell survival in a complex manner. A superoxide generator (menadione) enhanced the lethal effect of an organic peroxide (tert-butyl hydroperoxide) by 1,000-fold; conversely, treatment of cells with menadione plus H2O2 resulted in 100-fold protection compared to that for cells treated with the individual oxidants. Treatment of X. campestris with a combination of H2O2 and tert-butyl hydroperoxide elicited no additive or protective effect. High levels of catalase alone are sufficient to protect cells against the lethal effect of menadione plus H2O2 and tert-butyl hydroperoxide plus H2O2. These data suggest that H2O2 is the lethal agent responsible for killing the bacteria as a result of these treatments. However, increased expression of individual genes for peroxide (alkyl hydroperoxide reductase, catalase)- and superoxide (superoxide dismutase)-scavenging enzymes or concerted induction of oxidative stress-protective genes by menadione gave no protection against killing by a combination of menadione plus tert-butyl hydroperoxide. However, X. campestris cells in the stationary phase and a spontaneous H2O2-resistant mutant (X. campestris pv. phaseoli HR) were more resistant to killing by menadione plus tert-butyl hydroperoxide. These findings give new insight into oxidant killing of Xanthomonas spp. that could be generally applied to other bacteria. PMID:10966423

  12. Effects of Buffer Loading for Electrospray Ionization Mass Spectrometry of a Noncovalent Protein Complex that Requires High Concentrations of Essential Salts

    PubMed Central

    Sterling, Harry J.; Batchelor, Joseph D.; Wemmer, David E.; Williams, Evan R.

    2010-01-01

    Electrospray ionization (ESI) mass spectrometry (MS) is a powerful method for analyzing the active forms of macromolecular complexes of biomolecules. However, these solutions often contain high concentrations of salts and/or detergents that adversely effect ESI performance by making ion formation less reproducible, causing severe adduction or ion suppression. Many methods for separating complexes from nonvolatile additives are routinely used with ESI-MS, but these methods may not be appropriate for complexes that require such stabilizers for activity. Here, the effects of buffer loading using concentrations of ammonium acetate ranging from 0.22 to 1.41 M on the ESI mass spectra of a solution containing a domain truncation mutant of a σ54 activator from Aquifex aeolicus were studied. This 44.9 kDa protein requires the presence of millimolar concentrations of Mg2+, BeF3−, and ADP, (at ∼60 °C) to assemble into an active homo-hexamer. Addition of ammonium acetate can improve signal stability and reproducibility, and can significantly lower adduction and background signals. However, at higher concentrations, the relative ion abundance of the hexamer is diminished, while that of the constituent monomer is enhanced. These results are consistent with loss of enzymatic activity as measured by ATP hydrolysis and indicate that the high concentration of ammonium acetate interferes with assembly of the hexamer. This shows that buffer loading with ammonium acetate is effective for obtaining ESI signal for complexes that require high concentrations of essential salts, but can interfere with formation of, and/or destabilize complexes by disrupting crucial electrostatic interactions at high concentration. PMID:20226685

  13. Involvement of the Arp2/3 complex and WASP proteins in the effect of glutoxim and molixan on intracellular Ca(2+) concentration in macrophages.

    PubMed

    Krutetskaya, Z I; Milenina, L S; Naumova, A A; Butov, S N; Antonov, V G; Nozdrachev, A D

    2015-01-01

    The Fura-2AM fluorescent Ca(2+) probe was used to study the possibility that the Arp2/3 complex and WASP proteins are involved in the effects of glutoxim and molixan on the intracellular Ca(2+) concentration in macrophages. It has been demonstrated that preincubation of macrophages with inhibitors of the Arp2/3 complex or WASP proteins (CK-0944666 or wiskostatin, respectively) results in a significant suppression of Ca(2+)-responses induced by glutoxim or molixan. This suggests that polymerization of actin filaments is a process involved in the effect of glutoxim or molixan on intracellular Ca(2+) concentration in macrophages.

  14. Prevalence and Geographical Variation of Prothrombin G20210A Mutation in Patients with Cerebral Vein Thrombosis: A Systematic Review and Meta-Analysis

    PubMed Central

    Gonzalez, Joaquín V.; Barboza, Andrés G.; Vazquez, Fernando J.; Gándara, Esteban

    2016-01-01

    Objectives To compare the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis against healthy controls, and evaluate geographical variations. Design Systematic review and meta-analysis of case control studies. Methods We conducted a systematic review of electronic databases including MEDLINE and EMBASE. The main outcome was the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis; we also analyzed individual country variations in the prevalence. The random-effects model OR was used as the primary outcome measure. Results In total 19 studies evaluated 868 cases of cerebral venous thrombosis and 3981 controls. Prothrombin G20210A was found in 103/868 of the patients with cerebral venous thrombosis and 105/3999 of the healthy controls [random effects pooled OR 5.838, 95% CI 3.96 to 8.58; I217.9%]. The prevalence of prothrombin G20210A was significantly elevated in Italian studies (OR 9.69), in Brazilian studies (OR 7.02), and in German studies (OR 3.77), but not in Iranian studies (OR 0.98). Conclusion Prothrombin G20210A is significantly associated with cerebral venous thrombosis when compared to healthy controls, although this association is highly dependent on the country of origin. PMID:27031503

  15. Prevalence and Geographical Variation of Prothrombin G20210A Mutation in Patients with Cerebral Vein Thrombosis: A Systematic Review and Meta-Analysis.

    PubMed

    Gonzalez, Joaquín V; Barboza, Andrés G; Vazquez, Fernando J; Gándara, Esteban

    2016-01-01

    To compare the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis against healthy controls, and evaluate geographical variations. Systematic review and meta-analysis of case control studies. We conducted a systematic review of electronic databases including MEDLINE and EMBASE. The main outcome was the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis; we also analyzed individual country variations in the prevalence. The random-effects model OR was used as the primary outcome measure. In total 19 studies evaluated 868 cases of cerebral venous thrombosis and 3981 controls. Prothrombin G20210A was found in 103/868 of the patients with cerebral venous thrombosis and 105/3999 of the healthy controls [random effects pooled OR 5.838, 95% CI 3.96 to 8.58; I217.9%]. The prevalence of prothrombin G20210A was significantly elevated in Italian studies (OR 9.69), in Brazilian studies (OR 7.02), and in German studies (OR 3.77), but not in Iranian studies (OR 0.98). Prothrombin G20210A is significantly associated with cerebral venous thrombosis when compared to healthy controls, although this association is highly dependent on the country of origin.

  16. Classical Nuclear Hormone Receptor Activity as a Mediator of Complex Concentration Response Relationships for Endocrine Active Compounds

    PubMed Central

    Cookman, Clifford J.; Belcher, Scott M.

    2014-01-01

    Nonmonotonic concentration response relationships are frequently observed for endocrine active ligands that act via nuclear receptors. The curve of best fit for nonmonotonic concentration response relationships are often inverted U-shaped with effects at intermediate concentrations that are different from effects at higher or lower concentrations. Cytotoxicity is a major mode of action responsible for inverted U-shaped concentration response relationships. However, evidence suggests that ligand selectivity, activation of multiple molecular targets, concerted regulation of multiple opposing endpoints, and multiple ligand binding sites within nuclear receptors also contribute to nonmonotonic concentration response relationships of endocrine active ligands. This review reports the current understanding of mechanisms involved in classical nuclear receptor mediated nonmonotonic concentration response relationships with a focus on studies published between 2012 and 2014. PMID:25299165

  17. Mixing tests: diagnostic aides in the investigation of prolonged prothrombin times and activated partial thromboplastin times.

    PubMed

    Kershaw, Geoffrey; Orellana, Daniel

    2013-04-01

    Mixing tests are a relatively simple procedure used in the hemostasis laboratory as a first-line investigation into the cause of an abnormal screening test, typically a prolonged activated partial thromboplastin time and/or a prolonged prothrombin time. The mixing test involves combining the test plasma with normal plasma, then repeating the screening test on the mixture to assess whether the clotting time becomes normal or remains prolonged. The primary purpose of a mixing test is to guide further investigations. When mixing test results "normalize," this suggests the test plasma is deficient in clotting factor(s) and thus specific factor assays can be performed to determine which are reduced. When the mixing test result does not "normalize," this suggests the presence of an inhibitor or other type of interference (e.g., the presence of an anticoagulant such as high-dose heparinoids), and so the laboratory needs to determine if this is a lupus anticoagulant or a specific coagulation factor inhibitor, or another type of inhibitor. Because these follow-up investigations are more costly and time-consuming than the basic screening tests, the appropriate performance and interpretation of mixing tests is advantageous for the laboratory. Moreover, the correct laboratory approach is also clinically relevant, as patient management is ultimately affected, and an incorrect interpretation may lead to inappropriate therapies being established. Components of a mixing test that can influence result interpretation include the sensitivity of the used screening reagents to various factor deficiencies and inhibitors, the source or composition of the normal plasma, and the setting of cutoffs for the formula used in expressing mixing test results. Numerous and differing criteria for mixing test interpretation have been suggested historically, which can lead to confusion as to which approach is the most appropriate. The use of differing criteria will also lead to differing

  18. Homozygous factor V Leiden and double heterozygosity for factor V Leiden and prothrombin mutation.

    PubMed

    Saemundsson, Ymir; Sveinsdottir, Signý Vala; Svantesson, Henrik; Svensson, Peter J

    2013-10-01

    The most common forms of familial thrombophilia are factor V Leiden (FVL) and prothrombin mutation (PTM). Homozygous FVL and PTM have long been feared conditions thought to cause high rates of morbidity and mortality. To analyse clinical features in patients with homozygous FVL and PTM, as well as patients with double heterozygosity for FVL and PTM. All patients with homozygous FVL, PTM or double heterozygosity in the MATS database of 1465 consecutive unselected patients were analysed regarding age at inclusion venous thromboembolism (VTE), age at first thrombosis, recurrence, clinical course and acquired risk factors. We found 36 patients homozygous for FVL. Patients homozygous for FVL were younger than controls at group level (56 ± 18 vs. 63 ± 17, p < 0.02). Homozygous women were younger than female controls (50 ± 19 vs. 63 ± 18, p < 0.002). No difference was observed when comparing male subjects. Women were younger than men at inclusion thrombosis (50 ± 19 vs. 65 ± 14, p < 0.02) and at first thrombosis (47 ± 19 vs. 64 ± 14, p < 0.01). Deep venous thrombosis (DVT) was seen in 33 patients (92 %), 6 (17 %) had pulmonary embolism (PE) and 3 (8 %) had combined DVT and PE. PE was less frequent in homozygous FVL women compared to female controls (p < 0.03). VTE recurred in 3 subjects during the duration of the study. Odds ratio for VTE in homozygous FVL patients compared to controls was 13.9 (95 % CI 9.9-19.7). We found no subjects with homozygous PTM. Double heterozygosity for FVL and PTM was seen in 12 subjects. There was no difference in age at inclusion VTE between double heterozygotes and controls (59 ± 16 vs. 63 ± 17, ns.). DVT was seen in 92 % at inclusion, 8 % had PE. Mean age at first VTE was 52 ± 17 (27-82). Consecutive homozygous FVL patients had a higher age at first thrombosis than previously described. Homozygous females are affected at an earlier age than homozygous men and female controls. It seems that

  19. Serum des-R prothrombin activation peptide fragment 2: a novel prognostic marker for disseminated intravascular coagulation.

    PubMed

    Chung, Soie; Kim, Ji-Eun; Kim, Hyun Kyung; Yeon, Eun Hee; Shin, Yong Sung; Kim, Chul Woo

    2013-06-01

    Disseminated intravascular coagulation (DIC) is diagnosed based on the combination of predisposing underlying conditions and laboratory tests for plasma coagulation markers. Because the collection of blood plasma samples is a fastidious procedure, the serum sample method may be preferred for measurement of coagulation markers when feasible. The novel serum marker des-R prothrombin activation peptide fragment 2 (des-R F2) was measured using a sandwich enzyme-linked immunosorbent assay in 181 patients suspected of having DIC. Thrombin generation potential was estimated with a calibrated automated thrombogram. Serum des-R F2 was generated with an in vitro clotting process within a serum separation tube after blood collection. Carboxypeptidase inhibitor inhibited the formation of des-R F2 during in vitro clotting. Low levels of prothrombin and thrombin generation potential resulted in low serum des-R F2 levels. Serum des-R F2 was significantly decreased in overt DIC. Levels of des-R F2 correlated with DIC severity and other coagulation markers. Of note, the decrease in serum des-R F2 levels was a significant marker for predicting mortality. The serum marker, des-R F2, can be used for the investigation of DIC severity and prognosis. It should be considered a useful marker, especially when only serum samples are available. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Coagulation Factor Concentrates Fail to Restore Alterations in Fibrin Formation Caused by Rivaroxaban or Dabigatran in Studies With Flowing Blood From Treated Healthy Volunteers.

    PubMed

    Arellano-Rodrigo, Eduardo; Lopez-Vilchez, Irene; Galan, Ana M; Molina, Patricia; Reverter, Joan Carles; Carné, Xavier; Villalta, Jaume; Tassies, Dolors; Lozano, Miguel; Díaz-Ricart, Maribel; Escolar, Gines

    2015-10-01

    We evaluated the hemostatic alterations in blood from healthy individuals treated for 5 days with direct oral anticoagulants (DOACs) rivaroxaban (20 mg/d) or dabigatran (150 mg/12 h) in a single-blind clinical trial with crossover assignment (NCT01478282). We assessed the potential of prothrombin complex concentrates, activated prothrombin complex concentrates, or recombinant activated factor VII, when added ex vivo, to reverse the alterations caused by these DOACs. Blood was drawn at maximum plasma concentration after the last dose of each DOAC, and modifications in coagulation biomarkers were evaluated using a series of tests performed under steady conditions including routine coagulation, thrombin generation, and thromboelastometry assays. Additional studies in standardized flow devices were applied to evaluate alterations on platelet deposition and fibrin formation on damaged vascular surfaces exposed to flowing blood. Both DOACs caused important modifications of all coagulation biomarkers and significantly reduced fibrin formation in flow studies. Alterations in biomarkers observed in steady laboratory tests were normalized and occasionally overcompensated by procoagulant strategies. In contrast, reductions in fibrin formation observed in studies with flowing blood were improved, although never completely restored to baseline levels. Effects of dabigatran in flow studies appeared more resistant to reversal strategies than those of rivaroxaban. Inconsistencies between results of coagulation studies in steady or flowing assays not only raise concerns about the adequacy of the earlier tests to predict the restoration of the coagulopathy induced by DOACs but also suggest limitations of nonspecific procoagulant strategies to control severe coagulopathy in patients inadvertently overexposed these agents. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Complex Processing of a Titanium Magnetite Concentrate with Receiving the Products Containing Iron, The Titan and Vanadium

    NASA Astrophysics Data System (ADS)

    Naimanbayev, Madali; Dzurkanov, Zhantore; Lokhova, Nina; Maldybayev, Galymjan

    2016-10-01

    Present study determines conditions for titanium magnetite concentrate processing with fairly complete titanium conversion to the slag and iron and vanadium separation in the hot metal. It is quite difficult to process titanium magnetite concentrate in the blast furnaces due to low fusibility of charge and direct electrical melting which cause process instability. Present work is devoted to development of concentrate double stage smelting process with little soda additions, including solid-phase recovery at the first stage using specific coke as a reductant, avoiding concentrate oxidation and including its preliminary thermooxidation. Mix charge made of concentrate, soda and specific coke was granulated in water, dried at 130°C, pellets were placed in graphite crucible, and later on it was set up in the centre of the furnace in alundum crucible. Temperature regimen was fixed under following parameters: temperature at the first stage was 1250°C soaking time was 50 min; temperature at the second stage was 1500 - 1650°C soaking time was 35 min. It is established that little soda additive (estimated 3-4% Na2O) to the charge of titanium magnetite concentrate recovery smelting behaves as a coagulant during briquetting, as a catalyst in course of solid-phase recovery, as an inhibitor of DRI briquettes secondary oxidation as slag thinner during smelting. In course of titanium magnetite concentrate reduction smelting process, soda interacts to SiO2, AhO3, TiO2 oxides forming sodium silicates and titanates. Double-stage technology of titanium magnetite concentrate reduction smelting was used, both with soda addition, and without oxidation and preliminary iron oxidation of titanium magnetite concentrates till hematite was developed. Optimal process parameters were determined. Following parameters were obtained: hot metal yield was ∼⃒55% of concentrate weight, slag yield - 23.3-25.8%, carbon-free slag content, wt.%: Fe=1.0-1.6; TiO2=62.7-61.9. TiO2 yield in the slag was

  2. Colloids and organic matter complexation control trace metal concentration-discharge relationships in Marshall Gulch stream waters

    NASA Astrophysics Data System (ADS)

    Trostle, Kyle D.; Ray Runyon, J.; Pohlmann, Michael A.; Redfield, Shelby E.; Pelletier, Jon; McIntosh, Jennifer; Chorover, Jon

    2016-10-01

    This study combined concentration-discharge analyses (filtration at 0.45 μm), cascade filtrations (at 1.2, 0.4, and 0.025 μm) and asymmetrical flow field flow fractionation (AF4) to probe the influence of colloidal carriers (dissolved organic matter and inorganic nanoparticles) on observed concentration-discharge relationships for trace metals in a 155 ha forested catchment of the Santa Catalina Mountains Critical Zone Observatory (SCM CZO), Arizona. Many major elements (Na, Mg, Si, K, Ca) show no colloidal influence, and concentration-discharge relationships for these species are explained by previous work. However, the majority of trace metals (Al, Ti, V, Mn, Fe, Cu, Y, REE, U) show at least some influence of colloids on chemistry when filtered at the standard 0.45 μm cutoff. Concentration-discharge slopes of trace metals with modest colloidal influence are shallow (˜0.3) similar to that measured for dissolved organic carbon (DOC, 0.24), whereas elements with greater colloidal influence have steeper concentration-discharge slopes approaching that of Al (0.76), the element with the largest colloidal influence in this study (on average 68%). These findings are further supported by AF4 measurements that show distinct and resolvable pools of low hydrodynamic diameter DOC-sized material coexistent with larger diameter inorganic colloids, and the ratio of these carriers changes systematically with discharge because the DOC pool has a concentration-discharge relationship with shallower slope than the inorganic colloidal pool. Together these data sets illustrate that positive concentration-discharge slopes of trace metals in stream waters may be explained as the relative partitioning of trace metals between DOC and inorganic colloids, with contributions of the latter likely increasing as a result of increased prevalence of macropore flow.

  3. High internal phase emulsions stabilized solely by whey protein isolate-low methoxyl pectin complexes: effect of pH and polymer concentration.

    PubMed

    Wijaya, Wahyu; Van der Meeren, Paul; Wijaya, Christofora Hanny; Patel, Ashok R

    2017-02-22

    In recent years, there has been significant progress in edible emulsion technology especially with respect to creating and stabilizing surfactant-free emulsion systems for food applications. In this paper, we demonstrate the fabrication of high internal phase emulsions (HIPE) (φoil = 0.82) stabilized using colloidal complexes of non-gelling biopolymers (at concentrations as low as 0.3 wt%). The colloidal complexes were pre-formed by combining whey protein isolate (WPI) and low-methoxyl pectin (LMP) at three different pH values (i.e. pH 3.5, 4.5, 5.5) and used further for fabricating stable HIPEs. In addition to the effect of pH, the influence of total biopolymer concentration on the formation and properties of HIPEs was also evaluated. Depending on the total concentration of biopolymers used, the WPI-LMP complexes (formed at pH 4.5) showed a Z-average diameter in the range of 250-350 nm. It was found that the formation of HIPEs was strongly influenced by the pH of the colloidal complexes. At a pH close to the isoelectric point of WPI (≈pH 4.8) and WPI-LMP complexes (≈pH 3.4), severe aggregation of colloidal particles occurred, resulting in poor formation and stability of HIPEs. On comparing the stabilization behaviour of the complexes with the uncomplexed protein, it was noticed that the former provided comparatively better stabilization to the HIPEs against coalescence at pH 4.5 and 5.5. Based on the rheological data (low amplitude oscillatory shear rheology and flow measurements), all HIPE samples showed viscoelastic and shear-thinning behaviour. We believe that such viscoelastic gel-like systems could find potential commercial applications in the development of label-friendly novel food products with interesting textures.

  4. Free, complexed and total serum prostate specific antigen: the establishment of appropriate reference ranges for their concentrations and ratios.

    PubMed

    Oesterling, J E; Jacobsen, S J; Klee, G G; Pettersson, K; Piironen, T; Abrahamsson, P A; Stenman, U H; Dowell, B; Lövgren, T; Lilja, H

    1995-09-01

    Prostate specific antigen (PSA) exists in the serum in several molecular forms that can be measured by immunodetectable assays: free PSA, PSA complexed to alpha 1-antichymotrypsin (complexed PSA) and total PSA, which represents the sum of the free and complexed forms. We determined the normal distribution of values and established the appropriate reference ranges for these 3 molecular forms of PSA and their ratios (free-to-total, complexed-to-total and free-to-complexed PSA). Knowing the amount and ratio of these molecular forms appears to be useful in enhancing the ability of PSA to distinguish potentially curable prostate cancer from benign prostatic hyperplasia and in decreasing the number of unnecessary prostate biopsies. A total of 422 healthy men 40 to 79 years old was randomly chosen from the male population of Olmsted County, Minnesota and underwent a detailed clinical examination that included digital rectal examination, serum PSA determination and transrectal ultrasound to exclude the presence of prostate cancer. Using newly developed, monoclonal-monoclonal immunofluorometric assays for each molecular form, the free, complexed and total PSA, and the ratios of these 3 forms were determined for each study participant. All 3 molecular forms correlated directly with patient age (r = 0.45, r = 0.43 and r = 0.45, respectively). Using the 95th percentile, the recommended age-specific reference ranges for the free, complexed and total PSA forms, respectively, are 0.5, 1.0 and 2.0 ng./ml. for men 40 to 49 years old; 0.7, 1.5 and 3.0 ng./ml. for men 50 to 59 years old; 1.0, 2.0 and 4.0 ng./ml. for men 60 to 69 years old, and 1.2, 3.0 and 5.5 ng./ml. for men 70 to 79 years old. With regard to each of the ratios (free-to-total, complexed-to-total and free-to-complexed PSA) none correlated with patient age. As a result, the appropriate upper limit of normal (95th percentile) for all 3 ratios is constant for men of all ages. These reference ranges are greater than 0

  5. Functional properties and active-site topographies of factor X Gla- and prothrombin Gla-domain chimeras of activated protein C.

    PubMed

    Qureshi, Shabir H; Yang, Likui; Manithody, Chandrashekhara; Bae, Jong-Sup; Rezaie, Alireza R

    2008-09-01

    Substitution of the Gla-domain of activated protein C (APC) with the Gla-domain of prothrombin (APC-PTGla) improves the anticoagulant activity of APC independent of protein S. Previous FRET studies showed that this substitution alters the active-site topography of this mutant, rendering it identical to the active site of the APC-protein S complex. In this study, we characterized the functional properties and the active-site topography of another APC chimera containing the Gla-domain of factor X (APC-FXGla). We discovered that the anticoagulant activity of this mutant was similarly improved independent of protein S. The average distance of the closest approach (L) between the donor dye fluorescein attached to the active site of APC derivatives and the acceptor dye octadecylrhodamine incorporated into PC/PS vesicles was determined to be 99 A for APC and 84-86 A for both APC-PTGla and APC-FXGla. Protein S minimally influenced the L values of the APC chimeras, however, it lowered this value to 87 A for wild-type APC. Further studies revealed that neither chimera elicits a protective signaling response in the TNF-alpha-activated endothelial cells. These results suggest that unique structural features within the Gla-domain of APC enable the protease to interact with endothelial protein C receptor in the antiinflammatory pathway, while the same features also cause an inherently lower specific activity for APC in the anticoagulant pathway. This adaptation has made APC a cofactor-dependent protease, requiring the cofactor function of protein S for its optimal anticoagulant function, which appears to involve the alteration of the active-site topography of APC above the membrane surface.

  6. Determining the Concentration Dependent Transformations of Ag Nanoparticles in Complex Media: Using SP-ICP-MS and Au@Ag Core-Shell Nanoparticles as Tracers.

    PubMed

    Merrifield, Ruth C; Stephan, Chady; Lead, Jamie

    2017-03-21

    The fate, behavior, and impact of engineered nanoparticles (NPs) in toxicological and environmental media are driven by complex processes which are difficult to quantify. A key limitation is the ability to perform measurements at low and environmentally relevant concentrations, since concentration may be a key factor determining fate and effects. Here, we use single particle inductively coupled mass spectroscopy (SP-ICP-MS) to measure directly NP diameter and particle number concentration of suspensions containing gold-silver core-shell (Au@Ag) NPs in EPA moderately hard water (MHW) and MHW containing 2.5 mg L(-1) Suwannee River fulvic acid. The Au core of the Au@Ag NPs acts as an internal standard, and aids in the analysis of the complex Ag transformations. The high sensitivity of SP-ICP-MS, along with the Au@Ag NPs, enabled us to track the NP transformations in the range 0.01 and 50 μg L(-1), without further sample preparation. On the basis of the analysis of both Au and Ag parameters (size, size distribution, and particle number), concentration was shown to be a key factor in NP behavior. At higher concentration, NPs were in an aggregation-dominated regime, while at the lower and environmentally representative concentrations, dissolution of Ag was dominant and aggregation was negligible. In addition, further formation of ionic silver as Ag NPs in the form of AgS or AgCl was shown to occur. Between 1 and 10 μg L(-1), both aggregation and dissolution were important. The results suggest that, under realistic conditions, the role of NP homoaggregation may be minimal. In addition, the complexity of exposure and dose in dose-response relationships is highlighted.

  7. Airborne pollutant characteristics in an urban, industrial and agricultural complex metroplex with high emission loading and ammonia concentration.

    PubMed

    Tsai, Jiun-Horng; Chang, Li-Peng; Chiang, Hung-Lung

    2014-10-01

    The size distribution of particulate mass and water-soluble ionic constituents and their gaseous precursors was investigated in a subtropical area, southern Taiwan. Field sampling and chemical analysis of particulate matter (PM) were conducted using a Micro Orifice Uniform Deposition Impactor (MOUDI) and a Nano-MOUDI, and gaseous pollutants were determined by a denuder-filter pack system. PM size mass distribution, mass concentration and ionic species concentration were measured during the day and at night in the winter and summer. Average PM concentrations in the winter were as high as 132 ± 42 μg/m(3), and PM mass concentrations in the summer were as low as 38 ± 19 μg/m(3). Generally, PM concentration was 111 ± 60 μg/m(3) at night, which was 20% higher than that in the daytime. The size-segregated mass distribution of PM mass concentration was over 85% in the 0.1-3.2 μm range. Ammonium, nitrate, and sulfate were the dominant water-soluble ionic species in PM, contributing 34%-48% of PM mass. High ammonia (12.9-49 μg/m(3)) and SO2 (2.6-27 μg/m(3)) were observed in the gas precursors. The molar ratio [Formula: see text] was 3.18 ± 1.20 at PM1.0, which indicated that the PM was rich in ammonium. Therefore, the excess ammonium could neutralize nitrate to form ammonium nitrate, after the more stable ammonium sulfate and ammonium bisulfate formation. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Comparing prothrombin induced by vitamin K absence-II (PIVKA-II) with the oncofetal proteins glypican-3, Alpha feto protein and carcinoembryonic antigen in diagnosing hepatocellular carcinoma among Egyptian patients.

    PubMed

    Abd El Gawad, Iman A; Mossallam, Ghada I; Radwan, Noha H; Elzawahry, Heba M; Elhifnawy, Niveen M

    2014-06-01

    Hepatocellular carcinoma (HCC) is usually asymptomatic in the early stage and does not show elevated alpha-feto protein (AFP). AFP shows 60-80% sensitivity in diagnosing HCC. Glypican3 (GPC-3) is an oncofetal protein that is only detected in HCC cells but not in benign liver tissues, while Carcinoembryonic antigen (CEA) is expressed in various neoplasms including HCC. Although, it is not specific for HCC. Prothrombin induced by vitamin K absence-II (PIVKA-II) is an abnormal prothrombin protein that is increased in the serum of HCC patients. It has higher sensitivity and specificity compared to AFP. The aim of this study is to compare the clinical utility of PIVKA-II with GPC-3, AFP and CEA in diagnosing HCC. This study included 40 patients with HCC, 10 patients with cirrhosis as a benign control group, and 10 apparently healthy volunteers as normal controls. Serum samples were subjected to routine laboratory investigations, measurement of CEA, AFP using MEIA technique (Axsym), glypican3, and PIVKA-II using ELISA technique in the sera of all patients and controls. All markers showed the highest results in the HCC group. Higher concentrations of PIVKA-II were detected in patients with splenomegaly, and in tumors with size (>3cm). Combination of Glypican-3 and PIVKA-II showed the highest sensitivity, while GPC-3 alone and combination of GPC-3 and AFP showed the highest specificity to differentiate HCC from liver cirrhosis and normal controls. GPC-3, PIVKAII, and combination of both showed the highest sensitivity, while GPC-3 alone showed the highest specificity to differentiate HCC from liver cirrhosis. Glypican-3 is the only oncofetal antigen that showed comparable high diagnostic accuracy as PIVKA-II in diagnosing HCC among Egyptian patients. Copyright © 2014. Production and hosting by Elsevier B.V.

  9. Mineral concentrations of plasma and liver after injection with a trace mineral complex differ among Angus and Simmental cattle.

    PubMed

    Pogge, D J; Richter, E L; Drewnoski, M E; Hansen, S L

    2012-08-01

    To examine the effects of cattle breed on the clearance rate of an injectable mineral product, 10 Angus and 10 Simmental steers were blocked by breed and initial BW (332 ± 33 kg) and injected with either Multimin 90 (MM) or sterilized saline (CON) at a dose of 1 mL/45 kg BW. Multimin 90 contains 15 mg Cu/mL (as Cu disodium EDTA), 60 mg Zn/mL (as Zn disodium EDTA), 10 mg Mn/mL (as Mn disodium EDTA), and 5 mg Se/mL (as sodium selenite). Steers received a corn-silage-based diet, and inorganic sources of Cu, Zn, Mn, and Se were supplemented at NRC recommended amounts. Jugular blood was collected immediately before injection and at 8 and 10 h post-injection and on days 1, 8, and 15 post-injection. Liver biopsies were collected 3 d before injection and on days 1, 8, and 15 post-injection. Liver and plasma mineral concentration and glutathione peroxidase (GSH-Px) activity data were analyzed as repeated measures. Plasma concentrations of Zn, Mn, and Se were greater (P = 0.01) and Cu tended to be greater (P = 0.12) post-injection in MM steers compared with the CON steers. Regardless of treatment, Simmental cattle had lower plasma concentrations of Cu, Zn, and Se (P ≤ 0.05) when compared with Angus cattle. Erythrocyte GSH-Px activity was greater (P = 0.01) in MM steers compared with CON steers. Liver concentrations of Cu, Zn, and Se were greater (P = 0.05) in MM steers compared with CON steers post-injection. Liver Mn concentrations tended to be greater (P = 0.06) in MM steers compared with CON steers in the days post-injection. Interestingly, Simmental cattle exhibited greater (P = 0.01) liver Mn concentrations in the days after injection compared with Angus cattle (7.0 and 6.0 mg Mn/kg for Simmental and Angus cattle, respectively), regardless of treatment. It is unclear if this breed difference is biologically relevant; however, these data may suggest that differences in liver excretion of Mn exist between the two breeds. Overall, use of an injectable trace mineral

  10. Macrocyclic lanthanide complexes as artificial nucleases and ribonucleases: effects of pH, metal ionic radii, number of coordinated water molecules, charge, and concentrations of the metal complexes.

    PubMed

    Chang, C Allen; Wu, Bo Hong; Kuan, Bu Yuan

    2005-09-19

    We have been interested in the design, synthesis, and characterization of artificial nucleases and ribonucleases by employing macrocyclic lanthanide complexes because their high thermodynamic stability, low kinetic lability, high coordination number, and charge density (Lewis acidity) allow more design flexibility and stability. In this paper, we report the study of the use of the europium(III) complex, EuDO2A+ (DO2A is 1,7-dicarboxymethyl-1,4,7,10-tetraazacyclododecane) and other lanthanide complexes (i.e., LaDO2A+, YbDO2A+, EuK21DA+, EuEDDA+, and EuHEDTA where K21DA is 1,7-diaza-4,10,13-trioxacyclopentadecane-N,N'-diacetic acid, EDDA is ethylenediamine-N,N'-diacetic acid, and HEDTA is N-hydroxyethyl-ethylenediamine-N,N',N'-triacetic acid), as potential catalysts for the hydrolysis of the phosphodiester bond of BNPP (sodium bis(4-nitrophenyl)-phosphate). For the pH range 7.0-11.0 studied, EuDO2A+ promotes BNPP hydrolysis with the quickest rates among LaDO2A+, EuDO2A+, and YbDO2A+. This indicates that charge density is not the only factor affecting the reaction rates. Among the four complexes, EuDO2A+, EuK21DA+, EuEDDA+, and EuHEDTA, with their respective number of inner-sphere coordinated water molecules three, two, five, and three, EuEDDA+, with the greatest number of inner-sphere coordinated water molecules and a positive charge, promotes BNPP hydrolysis more efficiently at pH below 8.4, and the observed rate trend is EuEDDA+ > EuDO2A+ > EuK21DA+ > EuHEDTA. At pH > 8.4, the EuEDDA+ solution becomes misty and precipitates form. At pH 11.0, the hydrolysis rate of BNPP in the presence of EuDO2A+ is 100 times faster than that of EuHEDTA, presumably because the positively charged EuDO2A+ is more favorable for binding with the negatively charged phosphodiester compounds. The logarithmic hydrolysis constants (pKh) were determined, and are reported in the parentheses, by fitting the kinetic k(obs) data vs pH for EuDO2A+ (8.4), LaDO2A+ (8.4), YbDO2A+ (9.4), EuK21DA+ (7

  11. Characteristics of total gaseous mercury (TGM) concentrations in an industrial complex in South Korea: impacts from local sources

    NASA Astrophysics Data System (ADS)

    Seo, Yong-Seok; Jeong, Seung-Pyo; Holsen, Thomas M.; Han, Young-Ji; Choi, Eunhwa; Park, Eun Ha; Kim, Tae Young; Eum, Hee-Sang; Park, Dae Gun; Kim, Eunhye; Kim, Soontae; Kim, Jeong-Hun; Choi, Jaewon; Yi, Seung-Muk

    2016-08-01

    Total gaseous mercury (TGM) concentrations were measured every 5 min in Pohang, Gyeongsangbuk-do, Korea, during summer (17-23 August 2012), fall (9-17 October 2012), winter (22-29 January 2013), and spring (26 March-3 April 2013) to (1) characterize the hourly and seasonal variations of atmospheric TGM concentrations; (2) identify the relationships between TGM and co-pollutants; and (3) identify likely source directions and locations of TGM using the conditional probability function (CPF), conditional bivariate probability function (CBPF) and total potential source contribution function (TPSCF). The TGM concentration was statistically significantly highest in fall (6.7 ± 6.4 ng m-3), followed by spring (4.8 ± 4.0 ng m-3), winter (4.5 ± 3.2 ng m-3) and summer (3.8 ± 3.9 ng m-3). There was a weak but statistically significant negative correlation between the TGM concentration and ambient air temperature (r = -0.08, p<0.05). Although the daytime temperature (14.7 ± 10.0 °C) was statistically significantly higher than that in the nighttime (13.0 ± 9.8 °C) (p<0.05), the daytime TGM concentration (5.3 ± 4.7 ng m-3) was statistically significantly higher than that in the nighttime (4.7 ± 4.7 ng m-3) (p<0.01), possibly due to local emissions related to industrial activities and activation of local surface emission sources. The observed ΔTGM / ΔCO was significantly lower than that of Asian long-range transport, but similar to that of local sources in Korea and in US industrial events, suggesting that local sources are more important than those of long-range transport. CPF, CBPF and TPSCF indicated that the main sources of TGM were iron and manufacturing facilities, the hazardous waste incinerators and the coastal areas.

  12. Determination of the intracellular dissociation constant, K(D), of the fluo-3. Ca(2+) complex in mouse sperm for use in estimating intracellular Ca(2+) concentrations.

    PubMed

    Rockwell, P L; Storey, B T

    1999-12-01

    In order to calculate the actual, rather than the relative, intracellular Ca(2+) concentration (Ca(2+))(i) in mammalian sperm cells, using fluorescent probes whose fluorescence emission differs between the probe. Ca(2+) complex and free probe, the value of the dissociation constant for the probe. Ca(2+) complex, K(D), is required. Interaction of the probe with cellular components may change the intracellular value of K(D) from that determined in buffered solution. We had previously shown that fluo-3, whose Ca(2+) complex is highly fluorescent whereas free fluo-3 is not, could be used to monitor changes of (Ca(2+))(i) in mouse sperm. In this report, we describe a method for determining K(D) for the fluo-3. Ca(2+) complex in mouse sperm suspended in medium MJB, a medium in which the sperm remain viable, but which contains high Ca(2+). The method involved treating the sperm with ionomycin to provide a plasma membrane Ca(2+) carrier, with nigericin to eliminate pH gradient, and with gramicidin D to eliminate membrane potential, such that (Ca(2+))(i) equilibrates with medium Ca(2+) concentration (Ca(2+))(e), then titrating (Ca(2+))(e) with EGTA in added aliquots to near nil concentration. At EGTA concentrations in excess of total medium Ca(2+), an approximation algorithm was used to calculate (Ca(2+))(e), based on the known K(D) for the EGTA. Ca(2+) complex. The fluorescence of the intracellular fluo-3. Ca(2+) complex, F, decreased with increasing additions of EGTA; (Ca(2+))(i) = (Ca(2+))(e) was plotted as a linear function of F/[F(max) - F]; the slope gives K(D). At 37 degrees C, intracellular K(D) was calculated to be 0.636 +/- 0.018 microM (+/-SEM, n = 8). At 37 degrees C and 20 degrees C, K(D) values in MJB were calculated to be 0.502 +/- 0.022 and 0.578 +/- 0.029 (+/-SEM, n =8 and n = 6), respectively. The higher intracellular K(D) value implies probe interaction with cytosol components, primarily those in the head, as this compartment is the major contributor to

  13. Factor V Leiden 1691G/A and prothrombin gene 20210G/A polymorphisms as prothrombotic markers in adult Egyptian acute leukemia patients.

    PubMed

    El Sissy, Azza Hamdy; El Sissy, Maha H; Elmoamly, Shereef

    2014-11-01

    Factor V Leiden 1691G/A and prothrombin gene 20210G/A mutations are the most common genetic defects leading to thrombosis. This work aimed to study the FV Leiden and the prothrombin gene polymorphism in adult Egyptian patients with acute leukemia and their importance in thrombophilia screening. The study included 76 patients with acute leukemia and 100 healthy controls. Genotyping was done by real-time polymerase chain reaction technique. For factor V Leiden, the frequency of G/A mutation conferred more than 2.5-fold of increased risk of (OR 2.639 95 % CI 1.045-6.669). The frequency of factor V Leiden combined (G/A + A/A) genotypes conferred 2.83-fold of increased risk (OR 2.828, CI 1.13-7.075), The A allele conferred almost threefold increased risk (OR 2.824, 95 % CI 1.175-6.785). Despite higher frequency in patients compared to controls, there was no risk of association between prothrombin gene mutation and acute leukemia in adult Egyptians nor was there between combined genotypes of prothrombin gene mutation and factor V Leiden.

  14. Risk of Budd-Chiari Syndrome Associated with Factor V Leiden and G20210A Prothrombin Mutation: A Meta-Analysis

    PubMed Central

    Sun, Guixiang; Gao, Xiuyin; Wang, Hui; Yan, Wenjun; Xu, Hao; Zu, Maoheng; Ma, He; Wang, Wei; Lu, Zhaojun

    2014-01-01

    Background Various studies have demonstrated that factor V Leiden (FVL) and G20210A prothrombin mutation contribute to the risk of Budd-Chiari syndrome (BCS), while other studies provided conflicting findings. In order to derive more precise estimations of the relationships, a meta-analysis was performed. Methods Eligible articles were identified through search of databases including Pubmed, Chinese Biomedical Database (CBM, Chinese), and Chinese National Knowledge Infrastructure (CNKI, Chinese). Odd ratios (ORs) with 95% confidence intervals (CIs) were calculated using random- or fixed- model. Results Finally, twelve studies were included for FVL and nine studies were included for G20210A prothrombin mutation. With respect to FVL, significantly increased BCS risk was found in the overall population (OR = 6.29, 95%CI = 4.23–9.36). Subgroup analyses suggested that FVL was associated with an increased risk of BCS in the population with high background mutation prevalence (>1% in the normal population). No significant association was found between BCS and G20210A prothrombin mutation (OR = 1.78, 95%CI = 0.77–4.11). Conclusion The presence of FVL should be evaluated in patients with BCS. Conversely, G20210A prothrombin mutation is not significantly associated with risk of BCS. Large-scale well designed studies are necessary to be conducted to further confirm or refute the observed association. PMID:24755609

  15. The Aqueous Thermodynamics and Complexation Reactions of Anionic Silica Species to High Concentration: Effects on Neutralization of Leaked Tank Wastes and Migration of Radionuclides in the Subsurface

    SciTech Connect

    Felmy, Andrew R.; Choppin, Gregory; Dixon, David A.

    2002-06-01

    Highly basic tank wastes contain several important radionuclides, including {sup 90}Sr, {sup 99}Tc, and {sup 60}Co, as well as actinide elements (i.e., isotopes of U, Pu, and Am). These highly basic tank wastes are known to have leaked into the vadose zone at the Hanford Site. Upon entering the sediments in the vadose zone, the highly basic solutions dissolve large concentrations of silica from the silica and aluminosilicate minerals present in the subsurface. These dissolution reactions alter the chemical composition of the leaking solutions, transforming them from a highly basic (as high as 2M NaOH) solution into a pore solution with a very high concentration of dissolved silica and a significantly reduced pH. This moderately basic (pH 9 to 11), high-silica solution has the potential to complex radionuclides and move through the subsurface. Such strong radionuclide complexation is a currently unconsidered transport vector that has the potential to expedite radionuclide transport through the vadose zone. These strong complexation effects have the ability to significantly alter current conceptual models of contaminant migration beneath leaking tanks. In this project, we are determining the aqueous thermodynamics and speciation of dissolved silica and silica-radionuclide complexes to high silica concentration using a combination of (1) studies of chemical species structure and composition [via nuclear magnetic resonance (NMR) and, where applicable, laser-induced fluorescence spectroscopy and x-ray absorption spectroscopy] (2) molecular simulations to help identify key species structures and assist in interpreting experimental measurements (3) fundamental physical chemistry measurements, including solubility, electromotive force, and isopiestic measurements, to obtain the necessary thermodynamic data for predicting contaminant complexation and waste neutralization reactions. The radioactive elements we are studying include Sr, Co, Cs, Am(III), and U(VI).

  16. Effect of isotretinoin on prothrombin time (PT), international normalized ratio (INR), and activated partial thromboplastin time (aPTT).

    PubMed

    Kaptanoglu, Asli Feride; Uncu, Murat; Ozyurt, Selcuk; Hincal, Evren

    2013-08-01

    Patients with severe acne may need elective/urgent surgical interventions during treatment with isotretinoin and it is critical for the surgeon to consider the possible effects of this medication on coagulation systems. The aim of this study is to determine the changes in prothrombin time (PT), international normalized ratio (INR), and activated partial thromboplastin time (aPTT) during isotretinoin treatment. PT, aPTT, and INR values of 51 severe acne patients were evaluated during routine pre-treatment biochemical analysis. Only patients with normal values were included in the study. The results of before and after 1 month treatment were compared statistically. There were no statistically significant change in mean alanine aminotranferease (ALT), aspartate aminotransferase (AST), PT, and INR values after treatment. A significant increase in aPTT was detected. The INR values, which are more trusted and safe, showed no difference. Isotretinoin seems to have no effect on these coagulation parameters.

  17. [Cerebral sinovenous thrombosis in a girl with acute lymphoblastic leukaemia carrying the prothrombin G20210A variant].

    PubMed

    González García, H; Sacoto Erazo, G; Moreno Gómez, E; Blanco Quirós, A; Fernández Abril, M C; Alvarez Guisasola, F J

    2013-04-01

    Although cerebral venous thrombosis is rare, it is more commonly associated with children suffering from acute lymphoblastic leukaemia. We report the case of a 7-year-old girl who developed massive cerebral sinovenous thrombosis on day 22 of induction therapy for high-risk acute lymphoblastic leukaemia. Clinical symptoms were gradual onset of headache, decreasing consciousness, and ensuing left hemiplegia. A subsequent prothrombotic study revealed a heterozygous prothrombin G20210A variant in the child and mother. We analysed the prothrombotic factors found in the case before and after thrombosis. We confirm the importance of early exploration of patients for clinical predisposing risk factors of thrombosis and primary prothrombotic states in children with acute lymphoblastic leukaemia. This might help identify patients at particular risk from thrombosis and so administer thromboprophylaxis.

  18. Mesenteric vein thrombosis in a patient heterozygous for factor V Leiden and G20210A prothrombin genotypes.

    PubMed

    Karmacharya, Paras; Aryal, Madan Raj; Donato, Anthony

    2013-11-21

    Mesenteric venous thrombosis (MVT) is a rare but life threatening form of bowel ischemia. It is implicated in 6%-9% of all cases of acute mesenteric ischemia. The proportion of patients with primary (or idiopathic) MVT varies from 0% to 49%, with a decrease in frequency secondary to more recent availability of newer investigations for hypercoagulability. The presence of factor V Leiden (FVL) and prothrombin G20210A mutations (PGM) have been well documented in these cases. However, there have been scarce case reports describing MVT in heterozygotes of both these mutations occurring simultaneously and its implications on long term management. Our case describes acute MVT in a previously asymptomatic young patient with no prior history of venous thromboembolism. The patient was found to be heterozygous for FVL and PGM and treated with lifelong anticoagulation with warfarin (goal international normalized ratio: 2-3) and avoidance of hormonal contraceptives.

  19. Clinical significance of factor V leiden and prothrombin G20210A-mutations in cerebral venous thrombosis - comparison with arterial ischemic stroke.

    PubMed

    Beye, Aida; Pindur, Gerhard

    2017-08-28

    Cerebrovascular diseases are considered in a different way concerning their etiology with regard to arterial and venous occlusion. The role of thrombophilia in this context remains undetermined. For this reason, a case-control study was conducted including a total of 202 patients (154 females, 48 males) aged from 18 to 76 years (mean: 39.8 years) suffering either from cerebral sinus venous thrombosis (n = 101) or from arterial ischemic stroke (n = 101). Study groups were evaluated on the basis of age- and gender-matched pairs. Gene mutations of factor V-1691 (factor V Leiden) and prothrombin-20210 being considered as the most common thrombophilia markers were analyzed in this study. Factor V Leiden-mutations were found in 16.8% of patients with cerebral sinus venous thrombosis (CVT) and in 17.8% of patients with arterial ischemic stroke (AIS), which was significantly more frequent than in controls at a rate of 4.95% (ORs: 3.89 and 4.16). Prothrombin-mutations were significantly more frequent in CVT at a rate of 14.9% versus 2.97% in controls (OR: 5.70). This does not apply for AIS showing a rate of 4.95% prothrombin-mutations. Rates of factor V Leiden-mutations are not different in CVT compared with AIS. In contrast, however, prothrombin-mutations were significantly more frequent in CVT than in AIS with a rate of 14.9% versus 4.95% (OR 3.35). Furthermore, 3 cases with combined heterozygosity of factor V Leiden- and prothrombin-mutation have been identified in CVT, but not in AIS or controls. All of the above mentioned mutations were exclusively heterozygous. We conclude from these data that thrombophilia in terms of factor V Leiden genotype is a risk factor for both CVT and AIS in equal measure. In contrast, prothrombin-20210-mutations were different playing a significant role in the pathogenesis of cerebral sinus vein- thrombosis, but not in arterial ischemic stroke. Also, the combined occurrence of heterozygous prothrombin- and factor V Leiden

  20. Coagulation Factor IX concentrate: method of preparation and assessment of potential in vivo thrombogenicity in animal models.

    PubMed

    Menache, D; Behre, H E; Orthner, C L; Nunez, H; Anderson, H D; Triantaphyllopoulos, D C; Kosow, D P

    1984-12-01

    Thrombosis and/or disseminated intravascular coagulation (DIC) are complications specifically associated with the use of factor IX complex in some patients. Assuming that these complications might result from zymogen overload, we have produced, using diethylaminoethyl (DEAE)-Sephadex (Pharmacia, Piscataway, NJ) and sulfated dextran chromatography, a factor IX concentrate (coagulation factor IX) that is essentially free of prothrombin, factor VII, and factor X. Factor IX specific activity is at least 5 U/mg protein, a 250-fold purification compared to plasma. Amounts of factors II, VII, and X are less than 5 units each per 100 units of factor IX. The concentrate is essentially free of activated clotting factors and contains no added heparin. In the rabbit stasis model, a dose of 200 factor IX U/kg was less thrombogenic than 100 factor IX U/kg of the DEAE-Sephadex eluate from which the concentrate was derived. Infusion of 200 factor IX U/kg did not induce DIC in the nonstasis rabbit model, whereas 100 factor IX U/kg of the DEAE-Sephadex eluate resulted in DIC in this model. Several factor IX lots were found to have shortened nonactivated partial thromboplastin times (PTTs), but were nonthrombogenic in both animal models. These data indicate that coagulation factor IX concentrate is less thrombogenic than factor IX complex.

  1. On-line concentration of neutral analytes by complexation and acetonitrile sweeping in nonionic microemulsion electrokinetic chromatography with direct ultraviolet detection.

    PubMed

    Cao, Jun; Yi, Ling; Li, Ping; Chang, Yan-Xu

    2009-07-17

    To separate and detect neutral solutes in nonionic microemulsion electrokinetic chromatography (MEEKC), a novel method was developed, combining complex formation and acetonitrile (ACN) sweeping. In this report, dynamic borate complexation and on-line sweeping occurred simultaneously during a run. The operating parameters which affected the performance of analyte sweeping in nonionic MEEKC were examined in terms of borate complexation, ACN content, Brij-35 concentration and sample plug length. In addition, the validation of the method included tests of the limit of detection, reproducibility and sensitivity enhancement. 60-110-Fold of magnitude improvement in detection sensitivity for model compounds (ginsenoside Rf, ginsenoside Rb2, ginsenoside Re) using Brij-35 microemulsion was demonstrated. Furthermore, the method was applied to the determination of glucosides in the plant extract.

  2. Identification and quantification of ethyl carbamate occurring in urea complexation processes commonly utilized for polyunsaturated fatty acid concentration.

    PubMed

    Vázquez, Luis; Prados, Isabel M; Reglero, Guillermo; Torres, Carlos F

    2017-08-15

    The concentration of polyunsaturated fatty acids by formation of urea adducts from three different sources was studied to elucidate the formation of ethyl carbamates in the course of these procedures. Two different methodologies were performed: with ethanol at high temperature and with hexane/ethanol mixtures at room temperature. It was proved that the amount of urethanes generated at high temperature was higher than at room temperature. Besides, subsequent washing steps of the PUFA fraction with water were efficient to remove the urethanes from the final products. The methodology at room temperature with 0.4mL ethanol and 3g urea provided good relationship between concentration and yield of the main bioactive PUFA, with the lowest formation of ethyl carbamates in the process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. The copper-nickel concentration log: A tool for stratigraphic interpretation within the ultramafic and basal zones of the stillwater complex, Montana

    USGS Publications Warehouse

    Drew, L.J.; Bawiec, W.J.; Page, N.J.; Schuenemeyer, J.H.

    1985-01-01

    An analogue to the electric well log was devised for copper-nickel concentration drill-hole data from the Basal and lower part of the Ultramafic zones of the Stillwater Complex using automated data processing. The copper-nickel concentration logs graphically represent intensity (concentration) values that reflect the distribution of the elements in sulfide and silicate minerals. Four major patterns are recognized by their characteristic variations in copper and nickel intensity: (1) relatively flat, low-level copper-intensity signatures associated with arcuate nickel-intensity patterns that correlate with rocks in the Peridotite member of the Ultramafic zone; (2) arcuate or bulb-like patterns of copper and nickel intensity that correlate closely with the Basal bronzite cumulate member of the Basal zone; (3) complex patterns consisting of intervals of low-intensity copper and moderate-intensity nickel, spikes of high nickel and copper intensity, and high copper intensity associated with low nickel intensity that correlate respectively with cordierite-pyroxene hornfels, massive sulfide, norites and mineralized diabase dikes in the Basal norite member; and (4) large intervals of extremely low copper and nickel intensity that correlate with quartz-orthopyroxene hornfels. The recognition and interpretation of these patterns allow two- and three-dimensional stratigraphic and lithologic reconstructions to be done by means of concentration-log correlations instead of variable quality lithologic logging. ?? 1985.

  4. A deep vein thrombosis caused by 20209C>T mutation in homozygosis of the prothrombin gene in a Caucasian patient

    PubMed Central

    Álvarez, Silvia Izquierdo; Ollero, Eva Barrio; Llinares Sanjuan, Francisco Miguel; Martínez, Fabiola Lorente; Calvo Martín, María Teresa

    2014-01-01

    Introduction: Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient. Case and methods: The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab). Results: Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip. Conclusion: The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events. PMID:24627725

  5. [Factor V Leiden (G1691A) and prothrombin-G20210A alleles among patients with deep venous thrombosis and in the general population from Spain].

    PubMed

    Francès, Francesc; Portolès, Olga; Gabriel, Francisco; Corella, Dolores; Sorlí, José Vicente; Sabater, Antonio; Alfonso, José L; Guillén, Marisa

    2006-01-01

    Factor V leiden and the -G20210A variant of prothrombin gene are associated to a higher risk of deep venous thrombosis. To assess the frequency of factor V Leiden (G1691A) and prothrombin -G20210A alleles in patients with deep venous thrombosis (DVT) and in the general population from Spain. Factor V Leiden (g1691a) and prothrombin-g20210a alleles were genotyped in 493 individuals from the Spanish general populations and in 131 patients with DVT. The presence of DVT was confirmed by phlebography. Allelic frequencies and the DVT risk associated with these variants were estimated. Allelic frequencies for the factor V Leiden (G1691A) allele were 0.019 in patients with DVT and 0.010 in the general population (p=0.235). The frequencies for the prothrombin-G20210A allele were 0.027 and 0.026 (p=0.975). After adjustment for age and gender, the odds ratio for DVT, associated with the presence of G1691A allele was 2.41, but not statistically significant (95% confidence intervals 0.63-9.19). Prothrombin-G20210A allele was more prevelant than factor V Leiden (G1691A) allele in the Spanish population. However, the magnitude of the association between the G20210A and DVT risk is very low. On the contrary, the G1691A allele is associated by itself with a two fold increase in DVT risk in this population although without reaching statistical significance due to its low frequency.

  6. Influence of zinc concentration on structure, complex permittivity and permeability of Ni-Zn ferrites at high frequency

    NASA Astrophysics Data System (ADS)

    Jiang, Nan-Nan; Yang, Yang; Zhang, Yu-Xiang; Zhou, Jian-Ping; Liu, Peng; Deng, Chao-Yong

    2016-03-01

    Polycrystalline soft magnetic nickel-zinc ferrites with chemical composition Ni1-xZnxFe2O4, where x=0, 0.2, 0.4, 0.6, 0.65, 0.7, 0.75, and 0.8, were prepared by solid state reaction method. We researched the effect of zinc concentration on the lattice parameter, crystal morphology and electromagnetic properties at high frequency. Results show that ε‧ and ε″ decline with increasing frequency until they reach almost constants over 3 MHz to 1 GHz. The dielectric constant achieves a maximum when the Zn concentration is 0.8. The value of ε‧ slightly declines with increasing frequency in the range of 2-18 GHz. The spectra of the permeability displays a relaxation resonance for the ferrites with x=0, 0.2, and 0.4 in 3 MHz to 1 GHz frequency range. The permeability is ruled by Snoek's law, which results in the values of μ‧ decreased fast below 2 GHz and smaller than 1 above 2 GHz. The value of μ‧ reaches maximum and μ″ shows minimum for the samples around x=0.75 in 2-18 GHz range. The magnetic permeability μ‧ decreases in an external magnetic field, and shows two resonance peaks corresponding to domain wall and spin rotation resonance. The resonance peaks shift to higher frequency with increasing the external magnetic field. But the permeability has no clear response for magnetic field when zinc concentration is much higher.

  7. Peptide-bridged dinuclear Ru(II) complex for mitochondrial targeted monitoring of dynamic changes to oxygen concentration and ROS generation in live mammalian cells.

    PubMed

    Martin, Aaron; Byrne, Aisling; Burke, Christopher S; Forster, Robert J; Keyes, Tia E

    2014-10-29

    A novel mitochondrial localizing ruthenium(II) peptide conjugate capable of monitoring dynamic changes in local O2 concentrations within living cells is presented. The complex is comprised of luminescent dinuclear ruthenium(II) polypyridyl complex bridged across a single mitochondrial penetrating peptide, FrFKFrFK-CONH2 (r = D-arginine). The membrane permeability and selective uptake of the peptide conjugate at the mitochondria of mammalian cells was demonstrated using confocal microscopy. Dye co-localization studies confirmed very precise localization and preconcentration of the probe at the mitochondria. This precision permitted collection of luminescent lifetime images of the probe, without the need for co-localizing dye and permitted semiquantitative determination of oxygen concentration at the mitochondria using calibration curves collected at 37 °C for the peptide conjugate in PBS buffer. Using Antimycin A the ability of the probe to respond dynamically to changing O2 concentrations within live HeLa cells was demonstrated. Furthermore, based on lifetime data it was evident that the probe also responds to elevated reactive oxygen species (ROS) levels within the mitochondria, where the greater quenching capacity of these species led to luminescent lifetimes of the probe at longer Antimycin A incubation times which lay outside of the O2 concentration range. Although both the dinuclear complex and a mononuclear analogue conjugated to an octaarginine peptide sequence exhibited some cytotoxicity over 24 h, cells were tolerant of the probes over periods of 4 to 6 h which facilitated imaging. These metal-peptide conjugated probes offer a valuable opportunity for following dynamic changes to mitochondrial function which should be of use across domains in which the metabolic activity of live cells are of interest from molecular biology and drug discovery.

  8. Interactions between complicated flow-dispersion patterns and boundary layer evolution in a mountainous complex terrain during elevated SO2 concentrations

    NASA Astrophysics Data System (ADS)

    Matthaios, Vasileios N.; Triantafyllou, Athanassios G.; Garas, Stylianos; Krestou, Athina; Leivaditou, Elena

    2016-11-01

    The dispersion of air pollutants from multiple industrial stacks located in complex topography is an interesting subject. An attractive case is that of the wider region of Western Macedonia in NW Greece, where the greater amount of electric power of Greece is being produced by lignite power plant stations (LPPS). Considerable amounts of atmospheric pollutants are emitted by those LPPS into the atmosphere due to the quantities of coal burned. The variability of the topographic features and the terrain complexity of the area may lead to the formation of local atmospheric circulations of various types, which affect pollutant's transport and dispersion. In the present work, the dispersion conditions that favor the pollutants accumulation in the area are investigated. For this purpose, 1 year's hourly SO2 concentrations, surface wind measurements and a mesoscale meteorological and air pollution model (The Air Pollution Model, TAPM) were used. The SO2 and wind measurements were collected in situ from monitoring stations located nearby and at a greater distance from the power plants. Yearly and daily variations of SO2 concentrations are analyzed and discussed, and the period with the highest concentrations is selected. During this period, the evolution of the atmospheric boundary layer (ABL) in the area as well as the pollutants dispersion is examined. Statistical measures between modeled and observed meteorological data were in good agreement and a good correlation coefficient 0.68 and 0.98 was found in the SO2 variations. The analysis of the wind fields indicated better ventilation in the center of the area due to topographic venturi effects, while the dispersion mechanism which resulted in the relatively high ground level concentrations was fumigation. Finally, the evolution of the ABL was affected by the complex interactions between topography and mesoscale flows as it was found by the turbulent kinetic energy cross sections.

  9. Interactions between complicated flow-dispersion patterns and boundary layer evolution in a mountainous complex terrain during elevated SO2 concentrations

    NASA Astrophysics Data System (ADS)

    Matthaios, Vasileios N.; Triantafyllou, Athanassios G.; Garas, Stylianos; Krestou, Athina; Leivaditou, Elena

    2017-08-01

    The dispersion of air pollutants from multiple industrial stacks located in complex topography is an interesting subject. An attractive case is that of the wider region of Western Macedonia in NW Greece, where the greater amount of electric power of Greece is being produced by lignite power plant stations (LPPS). Considerable amounts of atmospheric pollutants are emitted by those LPPS into the atmosphere due to the quantities of coal burned. The variability of the topographic features and the terrain complexity of the area may lead to the formation of local atmospheric circulations of various types, which affect pollutant's transport and dispersion. In the present work, the dispersion conditions that favor the pollutants accumulation in the area are investigated. For this purpose, 1 year's hourly SO2 concentrations, surface wind measurements and a mesoscale meteorological and air pollution model (The Air Pollution Model, TAPM) were used. The SO2 and wind measurements were collected in situ from monitoring stations located nearby and at a greater distance from the power plants. Yearly and daily variations of SO2 concentrations are analyzed and discussed, and the period with the highest concentrations is selected. During this period, the evolution of the atmospheric boundary layer (ABL) in the area as well as the pollutants dispersion is examined. Statistical measures between modeled and observed meteorological data were in good agreement and a good correlation coefficient 0.68 and 0.98 was found in the SO2 variations. The analysis of the wind fields indicated better ventilation in the center of the area due to topographic venturi effects, while the dispersion mechanism which resulted in the relatively high ground level concentrations was fumigation. Finally, the evolution of the ABL was affected by the complex interactions between topography and mesoscale flows as it was found by the turbulent kinetic energy cross sections.

  10. The Complexity of Enzymic Control of Hydrogen Peroxide Concentration May Affect the Regeneration Potential of Plant Protoplasts.

    PubMed Central

    De Marco, A.; Roubelakis-Angelakis, K. A.

    1996-01-01

    Total peroxidase, NADH-peroxidase, ascorbate peroxidase, superoxide dismutase, and catalase activities were measured in tobacco (Nicotiana tabacum) leaves and in regenerating and nonregenerating protoplasts isolated from the same tissue and cultured for 2 weeks. The specific ranges of H2O2 concentration at which the enzymes scavenging the active forms of oxygen may efficiently operate and the activities of those enzymes were determined in an extract from tobacco leaves and in dividing and nondividing tobacco mesophyll protoplasts. The overall H2O2-scavenging enzyme activities were similar in both protoplast populations during the 2 to 3 d of culture. After 3 d, the regenerating protoplasts started to divide and both the antioxidant enzyme activities and the total peroxidase activity increased; in contrast, the viability and the H2O2-scavenging enzyme activities in nonregenerating protoplasts dramatically decreased. Surprisingly, the regenerative potentiality in dividing protoplasts was specifically correlated with a higher NADH-peroxidase activity, which resulted in a net H2O2 accumulation in the cells. Light, which causes the accumulation of active forms of oxygen in photosynthetic organelles, also stimulated catalase and ascorbate peroxidase activities in dividing protoplasts. We suggest that the localization of H2O2 rather than its absolute concentration might be responsible for oxidative stress and that controlled amounts of H2O2 are necessary to allow proper cell-wall reconstitution and the consequent cell division. PMID:12226176

  11. Molar Absorptivity and Concentration-Dependent Quantum Yield of Fe(II) Photo-Formation for the Aqueous Solutions of Fe(III)-Dicarboxylate Complexes

    NASA Astrophysics Data System (ADS)

    Hitomi, Y.; Arakaki, T.

    2009-12-01

    Redox cycles of iron in the aquatic environment affect formation of reactive oxygen species such as hydrogen peroxide and hydroxyl radicals, which in turn determines lifetimes of many organic compounds. Although aqueous Fe(III)-dicarboxylate complexes are considered to be important sources of photo-formed Fe(II), molar absorptivity and quantum yield of Fe(II) formation for individual species are not well understood. We initiated a study to characterize Fe(II) photo-formation from Fe(III)-dicarboxylates with the concentration ranges that are relevant to the natural aquatic environment. The Visual MINTEQ computer program was used to calculate the equilibrium concentrations of individual Fe(III)-dicarboxylate species. The molar absorptivity of Fe(III)-dicarboxylate species was obtained by UV-VIS spectrophotometer, and the product of the quantum yield and the molar absorptivity of Fe(III)-dicarboxylate species were obtained from photochemical experiments. These experimental data were combined with the calculated equilibrium Fe(III)-dicarboxylate concentrations to determine individual molar absorptivity and quantum yield of Fe(II) photo-formation for a specific Fe(III)-dicarboxylate species. We used initial concentrations of less than 10 micromolar Fe(III) to study the photochemical formation of Fe(II). Dicarboxylate compounds studied include oxalate, malonate, succinate, malate, and phthalate. We report molar absorptivity and concentration-dependent quantum yields of Fe(II) photo-formation of individual Fe(III)-dicarboxylates.

  12. Spatial and seasonal variabilities of the stable carbon isotope composition of soil CO2 concentration and flux in complex terrain

    NASA Astrophysics Data System (ADS)

    Liang, Liyin L.; Riveros-Iregui, Diego A.; Risk, David A.

    2016-09-01

    Biogeochemical processes driving the spatial variability of soil CO2 production and flux are well studied, but little is known about the variability in the spatial distribution of the stable carbon isotopes that make up soil CO2, particularly in complex terrain. Spatial differences in stable isotopes of soil CO2 could indicate fundamental differences in isotopic fractionation at the landscape level and may be useful to inform modeling of carbon cycling over large areas. We measured the spatial and seasonal variabilities of the δ13C of soil CO2 (δS) and the δ13C of soil CO2 flux (δP) in a subalpine forest ecosystem located in the Rocky Mountains of Montana. We found consistently more isotopically depleted values of δS and δP in low and wet areas of the landscape relative to steep and dry areas. Our results suggest that the spatial patterns of δS and δP are strongly mediated by soil water and soil respiration rate. More interestingly, our analysis revealed different temporal trends in δP across the landscape; in high landscape positions δP became more positive, whereas in low landscape positions δP became more negative with time. These trends might be the result of differential dynamics in the seasonality of soil moisture and its effects on soil CO2 production and flux. Our results suggest concomitant yet independent effects of water on physical (soil gas diffusivity) and biological (photosynthetic discrimination) processes that mediate δS and δP and are important when evaluating the δ13C of CO2 exchanged between soils and the atmosphere in complex terrain.

  13. Understanding climate sensitivity to greenhouse gas concentrations and orbital forcing in the cGenie Earth System Model of Intermediate Complexity

    NASA Astrophysics Data System (ADS)

    Rochholz, Fiona; Pälike, Heiko; Paul, André

    2017-04-01

    To better understand the Earth's climate system reaction to internal climate perturbations (i.e. changes in continental configuration or greenhouse gas concentrations) and external orbital forcing, it is crucial to determine the climate sensitivity of the system to various ranges of environmental boundary conditions. We examine the climate variability in response to orbital parameters and CO2 concentration in the atmosphere, using an Earth System Model of Intermediate Complexity (cGenie). Our low-resolution experiment model design uses a simple one-continent symmetry, includes a biogeochemical cycle, an ocean circulation and a simplified atmosphere. First we run fast models with constant values for precession, eccentricity and obliquity, thus creating strongly opposing insolation conditions, that identify variations of surface air temperature across continent and ocean. We test the sensitivity of the model to orbital variations with the initiation of a marine carbon cycle and the generation of more complex continental topologies. By changing the complexity of the carbon cycle, we quantify the effect of marine carbon cycling on the surface air temperature in a simplified world. In sensitivity experiments that run with the same model setup, we observe variations in the imprint of the orbital parameters on seasonal temperature when changing the atmospheric CO2 content. At predefined latitudes, weighted averages of mean surface air temperature across the continent and the ocean are calculated and used to estimate the impact of the orbital parameters.

  14. Concentration of copper and a copper-EDTA complex at the pH junction formed in soil by an electrokinetic remediation process.

    PubMed

    Kimura, Tomoyuki; Takase, Ken-Ichi; Tanaka, Shunitz

    2007-05-17

    The formation and stability of a pH junction was investigated, and the precipitation and accumulation of a metal hydroxide at the pH junction was confirmed. Moreover, the possibility that metal ions could be accumulated as a Me-EDTA complex at the pH junction was demonstrated. As a result, the pH junction where the acidic and alkali fronts of soil meet and the pH of soil changes rapidly, appeared at the 0.6 position in the EK process for 6-12 h. Copper ions accumulated in the form of copper hydroxide. EDTA was also concentrated in the position, in general agreement with the position of the pH junction. In addition to copper hydroxide, a copper-EDTA complex was concentrated at the 0.6 position from the anode after EK treatment for 12 h. The copper-EDTA complex was retained in 0.7 position from the anode after 12 h and, after 24 h, the position shifted to 0.8-0.9 from the anode. The possibility of accumulating metal ions within a narrow area, such as a pH junction was demonstrated.

  15. The effect of plasma antithrombin concentration on thrombin generation and fibrin gel structure.

    PubMed

    Elgue, G; Sanchez, J; Fatah, K; Olsson, P; Blombäck, B

    1994-07-15

    Congenital deficiency of antithrombin (AT) is associated with thrombotic events and AT consumption occurs in some severe disorders and after treatment with heparin. The aim of this study was to investigate whether variations in the level of plasma AT modify thrombin generation and the fibrin formation process after the intrinsic coagulation mechanism is triggered. Normal plasma was depleted of AT by immunoadsorption on CNBr-Sepharose coupled with the anti-AT-IgG fraction of antiserum. The AT-depleted plasma was reconstituted with AT (between 0.3 and 1.5 AT units per ml). Thrombin generation was measured as the development of thrombin-antithrombin complexes (TAT). The lag phase preceding fibrin formation depended on the concentration of AT. The short lag phase was seen in completely AT-depleted plasma and the long in plasma with 1.5 AT units per ml. TAT generation, determined in parallel consecutive samples, showed that the rate at which thrombin was generated was inverse to the AT concentration in plasma. The network structure of hydrated fibrin gels in the clotted plasma was studied by measuring the wavelength dependence of gel turbidity. The mass/length ratio value, -i.e. the thickness of fiber strands and porosity of the gel increased with increasing AT concentrations. It is concluded that plasma AT regulates the rate of prothrombin-thrombin conversion, the clotting time and the consequently network structure of the fibrin gel.

  16. VLA-4 integrin concentrates at the peripheral supramolecular activation complex of the immune synapse and drives T helper 1 responses.

    PubMed

    Mittelbrunn, María; Molina, Ana; Escribese, María M; Yáñez-Mó, María; Escudero, Ester; Ursa, Angeles; Tejedor, Reyes; Mampaso, Francisco; Sánchez-Madrid, Francisco

    2004-07-27

    The integrin alpha 4 beta 1 (VLA-4) not only mediates the adhesion and transendothelial migration of leukocytes, but also provides costimulatory signals that contribute to the activation of T lymphocytes. However, the behavior of alpha 4 beta 1 during the formation of the immune synapse is currently unknown. Here, we show that alpha 4 beta 1 is recruited to both human and murine antigen-dependent immune synapses, when the antigen-presenting cell is a B lymphocyte or a dendritic cell, colocalizing with LFA-1 at the peripheral supramolecular activation complex. However, when conjugates are formed in the presence of anti-alpha 4 antibodies, VLA-4 colocalizes with the CD3-zeta chain at the center of the synapse. In addition, antibody engagement of alpha 4 integrin promotes polarization toward a T helper 1 (Th1) response in human in vitro models of CD4(+) T cell differentiation and naïve T cell priming by dendritic cells. The in vivo administration of anti-alpha 4 integrin antibodies also induces an immune deviation to Th1 response that dampens a Th2-driven autoimmune nephritis in Brown Norway rats. These data reveal a regulatory role of alpha 4 integrins on T lymphocyte-antigen presenting cell cognate immune interactions.

  17. Blood macrophage colony-stimulating factor and thrombin-antithrombin III complex concentrations in pregnancy and preeclampsia.

    PubMed

    Hayashi, M; Numaguchi, M; Ohkubo, N; Yaoi, Y

    1998-04-01

    Macrophage colony-stimulating factor (M-CSF) is a characteristic cytokine that plays an essential role in placenta maintenance, and thrombin-antithrombin III complex (TAT) is a hemostatic marker that is remarkably altered both in normal pregnancy and in preeclampsia. The present study was designed in order to show various levels of M-CSF and TAT in pregnancies. Peripheral blood was collected from 49 subjects, of whom 31 were normal pregnant women consisting of the four groups (namely 10th, 20th, 30th, and 38th weeks of gestation), 13 were preeclamptic pregnant women (37th week of gestation; mean blood pressure, 158/99 mm Hg), and 5 were nonpregnant controls. We compared blood M-CSF and TAT levels among them. Results showed that blood M-CSF and TAT levels increased significantly with gestational age. Furthermore, the ratio of increase in M-CSF was significantly lower than that in TAT in normal pregnant women compared with controls. In contrast, the ratio of increase in M-CSF was significantly higher than that in TAT in preeclamptic women compared with normal pregnant women. These results concerning the ratio of increase in M-CSF and TAT have not been reported. These findings show that M-CSF level increases significantly in preeclampsia even in its earlier stage, exhibiting a systolic blood pressure of less than 160 mm Hg.

  18. VLA-4 integrin concentrates at the peripheral supramolecular activation complex of the immune synapse and drives T helper 1 responses

    NASA Astrophysics Data System (ADS)

    Mittelbrunn, María; Molina, Ana; Escribese, María M.; Yáñez-Mó, María; Escudero, Ester; Ursa, Ángeles; Tejedor, Reyes; Mampaso, Francisco; Sánchez-Madrid, Francisco

    2004-07-01

    The integrin 41 (VLA-4) not only mediates the adhesion and transendothelial migration of leukocytes, but also provides costimulatory signals that contribute to the activation of T lymphocytes. However, the behavior of 41 during the formation of the immune synapse is currently unknown. Here, we show that 41 is recruited to both human and murine antigen-dependent immune synapses, when the antigen-presenting cell is a B lymphocyte or a dendritic cell, colocalizing with LFA-1 at the peripheral supramolecular activation complex. However, when conjugates are formed in the presence of anti-4 antibodies, VLA-4 colocalizes with the CD3- chain at the center of the synapse. In addition, antibody engagement of 4 integrin promotes polarization toward a T helper 1 (Th1) response in human in vitro models of CD4+ T cell differentiation and naïve T cell priming by dendritic cells. The in vivo administration of anti-4 integrin antibodies also induces an immune deviation to Th1 response that dampens a Th2-driven autoimmune nephritis in Brown Norway rats. These data reveal a regulatory role of 4 integrins on T lymphocyte-antigen presenting cell cognate immune interactions.

  19. Dietary Tocotrienol/γ-Cyclodextrin Complex Increases Mitochondrial Membrane Potential and ATP Concentrations in the Brains of Aged Mice

    PubMed Central

    Schloesser, Anke; Esatbeyoglu, Tuba; Piegholdt, Stefanie; Dose, Janina; Ikuta, Naoko; Okamoto, Hinako; Ishida, Yoshiyuki; Terao, Keiji; Matsugo, Seiichi; Rimbach, Gerald

    2015-01-01

    Brain aging is accompanied by a decrease in mitochondrial function. In vitro studies suggest that tocotrienols, including γ- and δ-tocotrienol (T3), may exhibit neuroprotective properties. However, little is known about the effect of dietary T3 on mitochondrial function in vivo. In this study, we monitored the effect of a dietary T3/γ-cyclodextrin complex (T3CD) on mitochondrial membrane potential and ATP levels in the brain of 21-month-old mice. Mice were fed either a control diet or a diet enriched with T3CD providing 100 mg T3 per kg diet for 6 months. Dietary T3CD significantly increased mitochondrial membrane potential and ATP levels compared to those of controls. The increase in MMP and ATP due to dietary T3CD was accompanied by an increase in the protein levels of the mitochondrial transcription factor A (TFAM). Furthermore, dietary T3CD slightly increased the mRNA levels of superoxide dismutase, γ-glutamyl cysteinyl synthetase, and heme oxygenase 1 in the brain. Overall, the present data suggest that T3CD increases TFAM, mitochondrial membrane potential, and ATP synthesis in the brains of aged mice. PMID:26301044

  20. Method for determining molar concentrations of metabolites in complex solutions from two-dimensional 1H-13C NMR spectra.

    PubMed

    Lewis, Ian A; Schommer, Seth C; Hodis, Brendan; Robb, Kate A; Tonelli, Marco; Westler, William M; Sussman, Michael R; Markley, John L

    2007-12-15

    One-dimensional (1D) (1)H nuclear magnetic resonance (NMR) spectroscopy is used extensively for high-throughput analysis of metabolites in biological fluids and tissue extracts. Typically, such spectra are treated as multivariate statistical objects rather than as collections of quantifiable metabolites. We report here a two-dimensional (2D) (1)H-(13)C NMR strategy (fast metabolite quantification, FMQ, by NMR) for identifying and quantifying the approximately 40 most abundant metabolites in biological samples. To validate this technique, we prepared mixtures of synthetic compounds and extracts from Arabidopsis thaliana, Saccharomyces cerevisiae, and Medicago sativa. We show that accurate (technical error 2.7%) molar concentrations can be determined in 12 min using our quantitative 2D (1)H-(13)C NMR strategy. In contrast, traditional 1D (1)H NMR analysis resulted in 16.2% technical error under nearly ideal conditions. We propose FMQ by NMR as a practical alternative to 1D (1)H NMR for metabolomics studies in which 50-mg (extract dry weight) samples can be obtained.

  1. Evaluation of AERMOD and CALPUFF for predicting ambient concentrations of total suspended particulate matter (TSP) emissions from a quarry in complex terrain.

    PubMed

    Tartakovsky, Dmitry; Broday, David M; Stern, Eli

    2013-08-01

    Concentrations of particulate emissions from a quarry located in hilly terrain were calculated by two common atmospheric dispersion models, AERMOD and CALPUFF. Evaluation of these models for emissions from quarries/open pit mines that are located in complex topography is missing from the literature. Due to severe uncertainties in the input parameters, numerous scenarios were simulated and model sensitivity was studied. Model results were compared among themselves, and to measured total suspended particulate (TSP). For a wide range of meteorological and topographical conditions studied, AERMOD predictions were in a better agreement with the measurements than those obtained by CALPUFF. The use of AERMOD's "Open pit" tool seems unnecessary when accurate digital topographic data are available. Onsite meteorological data are shown to be crucial for reliable dispersion calculations in complex terrain. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Covalent co-immobilization of heparin/laminin complex that with different concentration ratio on titanium surface for selectively direction of platelets and vascular cells behavior

    NASA Astrophysics Data System (ADS)

    Wang, Jian; Chen, Yuan; Liu, Tao; Wang, Xue; Liu, Yang; Wang, Yuan; Chen, Junying; Huang, Nan

    2014-10-01

    Surface biofunctional modification of coronary artery stent to improve the hemocompatibility and selectively accelerate endothelium regeneration but prevent restenosis have been become a new hotspot. For this, a novel method was developed in this work by co-immobilization of Ln and heparin complex on poly-L-lysine modified Ti surface. Take the advantage of the specific interaction between Ln and heparin, Ln and heparin complexes with different concentration ratios were set up for creating different exposure density of these two types of biomolecules. According to biocompatibility evaluation results, the Hep/Ln complexes modified surface displayed less platelet adhesion and activation. Especially, on L(150)H and L(200)H surface, the AT III binding quantity, APTT value and anti-coagulation property of modified surface were significantly promoted. Furthermore, the adherent density and proliferation activity of ECs and EPCs were positively correlated with Ln concentration. Notably, the proliferation of both ECs and EPCs on L(100)H, L(150)H and L(200)H surface were greatly promoted. Another hand, the proliferation activity of SMCs was significantly inhibited on Hep/Ln modified surfaces, which was considered mainly due to the inhibitory effect of heparin to SMCs. According to the existing results, this study demonstrated that in a certain range of heparin and laminin concentration ratio, the biological behavior of platelets, ECs, EPCs and SMCs could be selectively directed. We suggested that this article provided a potential method to construct an adequate platform on a stent surface for accelerate endothelialization with low side effects.

  3. First data on the concentrations and distribution of noble metals in Riphean magmatic complexes of the Bashkir meganticlinorium and eastern margin of the East European Platform

    NASA Astrophysics Data System (ADS)

    Kovalev, S. G.; Puchkov, V. N.; Vysotsky, S. I.; Kovalev, S. S.

    2016-12-01

    The noble metal (PGE and Au) geochemical specialization of igneous rocks of the Bashkir meganticlinorium and adjacent areas of the East European Platform is characterized for the first time. The identical plots of normalized PGE and Au concentrations of igneous rocks in these regions indicate similar conditions and mechanisms of the formation of the noble metal geochemical specialization during the emplacement of magmatic bodies. It is established that a specific feature of noble metal geochemical specialization (the "rhodium anomaly") in magmatic complexes of the Bashkir meganticlinorium and eastern areas of the East European Platform is determined by the concentrations of noble metals in sulfide minerals (pentlandite); i.e., it is "primary" in origin.

  4. Process feasibility, operational parameters and modeling of reverse osmosis membrane systems for the separation and concentration of hazardous, complex industrial wastes

    SciTech Connect

    Slater, C.S.

    1983-01-01

    Reverse osmosis (RO) was applied successfully to the renovation of complex and hazardous industrial wastewaters. Few others have had success in applying RO to the treatment of these high-strength wastewaters, including industrial landfill leachates. Because of the nature of these hazardous waste streams, difficulties are encountered if the RO treatment scheme is not designed or operated for the immediate purpose. The RO system consists of tubular cellulose acetate membranes that can operate in several process modes. The more functional process concentrates the feed, allowing the membrane to separate increments of

  5. Complex Catchment Processes that Control Stream Nitrogen and Organic Matter Concentrations in a Northeastern USA Upland Catchment

    NASA Astrophysics Data System (ADS)

    Sebestyen, S. D.; Shanley, J. B.; Pellerin, B.; Saraceno, J.; Aiken, G. R.; Boyer, E. W.; Doctor, D. H.; Kendall, C.

    2009-05-01

    There is a need to understand the coupled biogeochemical and hydrological processes that control stream hydrochemistry in upland forested catchments. At watershed 9 (W-9) of the Sleepers River Research Watershed in the northeastern USA, we use high-frequency sampling, environmental tracers, end-member mixing analysis, and stream reach mass balances to understand dynamic factors affect forms and concentrations of nitrogen and organic matter in streamflow. We found that rates of stream nitrate processing changed during autumn baseflow and that up to 70% of nitrate inputs to a stream reach were retained. At the same time, the stream reach was a net source of the dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) fractions of dissolved organic matter (DOM). The in-stream nitrate loss and DOM gains are examples of hot moments of biogeochemical transformations during autumn when deciduous litter fall increases DOM availability. As hydrological flowpaths changed during rainfall events, the sources and transformations of nitrate and DOM differed from baseflow. For example, during storm flow we measured direct inputs of unprocessed atmospheric nitrate to streams that were as large as 30% of the stream nitrate loading. At the same time, stream DOM composition shifted to reflect inputs of reactive organic matter from surficial upland soils. The transport of atmospheric nitrate and reactive DOM to streams underscores the importance of quantifying source variation during short-duration stormflow events. Building upon these findings we present a conceptual model of interacting ecosystem processes that control the flow of water and nutrients to streams in a temperate upland catchment.

  6. Effect of Low-Dose Ferrous Sulfate vs Iron Polysaccharide Complex on Hemoglobin Concentration in Young Children With Nutritional Iron-Deficiency Anemia: A Randomized Clinical Trial.

    PubMed

    Powers, Jacquelyn M; Buchanan, George R; Adix, Leah; Zhang, Song; Gao, Ang; McCavit, Timothy L

    2017-06-13

    Iron-deficiency anemia (IDA) affects millions of persons worldwide, and is associated with impaired neurodevelopment in infants and children. Ferrous sulfate is the most commonly prescribed oral iron despite iron polysaccharide complex possibly being better tolerated. To compare the effect of ferrous sulfate with iron polysaccharide complex on hemoglobin concentration in infants and children with nutritional IDA. Double-blind, superiority randomized clinical trial of infants and children aged 9 to 48 months with nutritional IDA (assessed by history and laboratory criteria) that was conducted in an outpatient hematology clinic at a US tertiary care hospital from September 2013 through November 2015; 12-week follow-up ended in January 2016. Three mg/kg of elemental iron once daily as either ferrous sulfate drops or iron polysaccharide complex drops for 12 weeks. Primary outcome was change in hemoglobin over 12 weeks. Secondary outcomes included complete resolution of IDA (defined as hemoglobin concentration >11 g/dL, mean corpuscular volume >70 fL, reticulocyte hemoglobin equivalent >25 pg, serum ferritin level >15 ng/mL, and total iron-binding capacity <425 μg/dL at the 12-week visit), changes in serum ferritin level and total iron-binding capacity, adverse effects. Of 80 randomized infants and children (median age, 22 months; 55% male; 61% Hispanic white; 40 per group), 59 completed the trial (28 [70%] in ferrous sulfate group; 31 [78%] in iron polysaccharide complex group). From baseline to 12 weeks, mean hemoglobin increased from 7.9 to 11.9 g/dL (ferrous sulfate group) vs 7.7 to 11.1 g/dL (iron complex group), a greater difference of 1.0 g/dL (95% CI, 0.4 to 1.6 g/dL; P < .001) with ferrous sulfate (based on a linear mixed model). Proportion with a complete resolution of IDA was higher in the ferrous sulfate group (29% vs 6%; P = .04). Median serum ferritin level increased from 3.0 to 15.6 ng/mL (ferrous sulfate) vs 2.0 to 7.5 ng/mL (iron complex) over

  7. Relationship between the peripheral concentrations of estradiol-17β (E2) and preovulatory characteristics of cumulus-oocyte complexes (COCs) during superovulation treatment in Japanese Black cows.

    PubMed

    Kitahara, Go; Kamimura, Shunichi; Hamana, Katsumi

    2011-02-01

    The relationship between the peripheral concentrations of estradiol-17β (E(2)) and the preovulatory characteristics of cumulus oocyte complexes (COCs) during superovulation treatment was investigated in Japanese Black cows. A superovulation regimen with FSH treatment in a descending manner was commenced on day 7 (n=3) or day 10 (n=2) of the estrous cycle (day 0=estrus). Peripheral blood was collected to measure E(2) concentrations twice a day throughout the treatment. Ovariectomies were performed at 100 h after the initial FSH treatment in five cows. Every follicle more than 8 mm in diameter was isolated from the ovaries, and cumulus-oocyte complexes (COCs) were gently aspirated. The COCs were then separated into three groups based on the characteristics of the cumulus (compact, expanded and denuded) and subgrouped based on the stage of the nucleus in the oocytes (GV, GVBD). Plasma E(2) concentrations tended to increase gradually and reached the peak level at around 84 h (E(2)-84: n=3) or 96 h (E(2)-96: n=2) after the initial FSH treatment. The ratio of COCs with expanded cumulus was significantly higher in E(2)-84 than in E(2)-96 (P<0.01). However, there was no difference in the ratio of oocytes showing GVBD between E(2)-84 and E(2)-96 (P=0.73), and the characteristics of the cumulus did not affect the stage of the nucleus in the oocytes in either groups (compact, expanded and nude; P=0.61, 0.81 and 1.00). It was possible that the time until the peak plasma E(2) concentrations after the FSH treatment could become an indicator for the maturation of follicles and oocytes in preovulatory follicles during superovulation treatment in Japanese Black cows.

  8. The relationship between the bone mineral density and urinary cadmium concentration of residents in an industrial complex

    SciTech Connect

    Shin, Minah; Paek, Domyung; Yoon, Chungsik

    2011-01-15

    Background: An association between cadmium exposure and bone mineral density (BMD) has been demonstrated in elderly women, but has not been well studied in youths and men. Some studies report either no or a weak association between cadmium exposure and bone damage. Objectives: This study was designed to investigate the relationship between the urinary cadmium (U-Cd) levels and BMD of females and males of all ages. Methods: A total of 804 residents near an industrial complex were surveyed in 2007. U-Cd and BMD on the heel (non-dominant calcaneus) were analyzed with AAS-GTA and Dual-Energy X-ray absorptiometry, respectively. Demographic characteristics were collected by structured questionnaires. Osteoporosis and osteopenia were defined by BMD cut-off values and T-scores set by the WHO; T score>-1, normal; -2.5=}1.0 {mu}g/g creatinine) in females (OR=2.92; 95% CI, 1.51-5.64) and in males (OR=3.37; 95% CI, 1.09-10.38). With the multiple linear regression model, the BMD of the adult group was negatively associated with U-Cd (<0.05), gender (female, p<0.001) and age (p<0.001). The BMD of participants who were {<=}19 years of age was negatively associated with gender (female, p<0.01), whereas it was positively associated with age and BMI (p<0.001). BMD was not associated with exercise, smoking habits, alcohol consumption, job or parental education. Conclusion: Results suggested that U-Cd might be associated with osteopenia as well as osteoporosis in both male and female adults. Age and female gender were negatively associated with BMD in the adult group, whereas age was positively

  9. Compound-Specific Stable Carbon Isotope Analysis of Low-Concentration Complex Hydrocarbon Mixtures from Natural Gas Hydrate Systems

    NASA Astrophysics Data System (ADS)

    Plummer, R. E.; Pohlman, J. W.; Coffin, R. B.

    2005-12-01

    A system has been developed to measure the stable carbon isotope (δ13C) composition of dissolved methane, ethane, and propane from natural sediment samples with headspace concentrations as low as 1 ppm using a modified Thermo Electron Trace gas chromatograph (GC) connected to a Finnigan Delta Plus XP isotope ratio mass spectrometer (IRMS). A cryofocusing inlet was connected to the GC which allows 0.02- to 15.0-ml injections into a 10-ml min-1 He carrier stream. Analytes from the variable-volume injection are focused into a small section of fused silica capillary, which is either empty or packed with Poraplot-Q, depending on the analyte(s) of interest. The analytes are then rapidly desorbed (100°C) onto the GC column (1.8 ml min-1), where they undergo separation, combustion and IRMS detection. The sensitivity of the IRMS was improved by the addition of high resistivity amplifiers so that measurements can be obtained with as little as 7-ng of carbon. The analytical precision (2σ) is less than 0.5‰ for methane analysis and less than 1‰ for ethane and propane analyses. The gases are standardized by tank CO2 which has been referenced to the NIST RM 8560 natural gas standard. The samples require no pretreatment, and can be analyzed rapidly (20 samples/day) and with minimal instrument training. Using this system, we have obtained complete stable carbon isotope ethane profiles from sediment cores from microbial and thermogenic gas hydrate regions on the Northern Cascadia Margin. We were able to differentiate the relative thermal and microbial contributions of the gases; and furthermore, we obtained clear evidence for ethanogenesis and ethane oxidation at depths similar to those where methanogenesis and anaerobic methane oxidation (AOM), respectively, occurred. This system will be utilized to analyze headspace and hydrate gas samples from IODP Leg 311. These data will allow us to fully characterize the thermogenic contributions and trace hydrocarbon biogeochemical

  10. At clinically relevant concentrations the anaesthetic/amnesic thiopental but not the anticonvulsant phenobarbital interferes with hippocampal sharp wave-ripple complexes

    PubMed Central

    Papatheodoropoulos, Costas; Sotiriou, Evangelos; Kotzadimitriou, Dimitrios; Drimala, Panagiota

    2007-01-01

    Background Many sedative agents, including anesthetics, produce explicit memory impairment by largely unknown mechanisms. Sharp-wave ripple (SPW-R) complexes are network activity thought to represent the neuronal substrate for information transfer from the hippocampal to neocortical circuits, contributing to the explicit memory consolidation. In this study we examined and compared the actions of two barbiturates with distinct amnesic actions, the general anesthetic thiopental and the anticonvulsant phenobarbital, on in vitro SPW-R activity. Results Using an in vitro model of SPW-R activity we found that thiopental (50–200 μM) significantly and concentration-dependently reduced the incidence of SPW-R events (it increased the inter-event period by 70–430 %). At the concentration of 25 μM, which clinically produces mild sedation and explicit memory impairment, thiopental significantly reduced the quantity of ripple oscillation (it reduced the number of ripples and the duration of ripple episodes by 20 ± 5%, n = 12, P < 0.01), and suppressed the rhythmicity of SPWs by 43 ± 15% (n = 6, P < 0.05). The drug disrupted the synchrony of SPWs within the CA1 region at 50 μM (by 19 ± 12%; n = 5, P < 0.05). Similar effects of thiopental were observed at higher concentrations. Thiopental did not affect the frequency of ripple oscillation at any of the concentrations tested (10–200 μM). Furthermore, the drug significantly prolonged single SPWs at concentrations ≥50 μM (it increased the half-width and the duration of SPWs by 35–90 %). Thiopental did not affect evoked excitatory synaptic potentials and its results on SPW-R complexes were also observed under blockade of NMDA receptors. Phenobarbital significantly accelerated SPWs at 50 and 100 μM whereas it reduced their rate at 200 and 400 μM. Furthermore, it significantly prolonged SPWs, reduced their synchrony and reduced the quantity of ripples only at the clinically very high concentration of 400

  11. Combined heterozygosity of factor V leiden and the G20210A prothrombin gene mutation in a patient with cerebral cortical vein thrombosis.

    PubMed

    Liu, X Y; Gabig, T G; Bang, N U

    2000-07-01

    Cerebral venous thrombosis (CVT) is a rare type of stroke with a variety of causes. Several reports have suggested that either factor V Leiden or G20210A prothrombin gene mutation is associated with an increased risk of CVT. The genetic thrombophilias are typically associated with other predisposing factors. We report a unique case of CVT in a patient with both the factor V Leiden and the G20210A prothrombin gene mutations without other identifiable precipitating factors in a 28-year-old white male in good health. MRI and cerebral arterial angiography showed cerebral cortical venous thrombosis. This case suggests that combined heterozygous individuals may be particularly prone to spontaneous thrombosis, like CVT.

  12. Charge carrier effective mass and concentration derived from combination of Seebeck coefficient and 125Te NMR measurements in complex tellurides

    NASA Astrophysics Data System (ADS)

    Levin, E. M.

    2016-06-01

    Thermoelectric materials utilize the Seebeck effect to convert heat to electrical energy. The Seebeck coefficient (thermopower), S , depends on the free (mobile) carrier concentration, n , and effective mass, m*, as S ˜m*/n2 /3 . The carrier concentration in tellurides can be derived from 125Te nuclear magnetic resonance (NMR) spin-lattice relaxation measurements. The NMR spin-lattice relaxation rate, 1 /T1 , depends on both n and m* as 1 /T1˜(m*)3/2n (within classical Maxwell-Boltzmann statistics) or as 1 /T1˜(m*)2n2 /3 (within quantum Fermi-Dirac statistics), which challenges the correct determination of the carrier concentration in some materials by NMR. Here it is shown that the combination of the Seebeck coefficient and 125Te NMR spin-lattice relaxation measurements in complex tellurides provides a unique opportunity to derive the carrier effective mass and then to calculate the carrier concentration. This approach was used to study A gxS bxG e50-2xT e50 , well-known GeTe-based high-efficiency tellurium-antimony-germanium-silver thermoelectric materials, where the replacement of Ge by [Ag+Sb] results in significant enhancement of the Seebeck coefficient. Values of both m* and n derived using this combination show that the enhancement of thermopower can be attributed primarily to an increase of the carrier effective mass and partially to a decrease of the carrier concentration when the [Ag+Sb] content increases.

  13. Investigating the differences between receptor and dispersion modeling for concentration prediction and health risk assessment of volatile organic compounds from petrochemical industrial complexes.

    PubMed

    Chen, Wei-Hsiang; Chen, Zheng-Bin; Yuan, Chung-Shin; Hung, Chung-Hsuang; Ning, Shu-Kuang

    2016-01-15

    Receptor and dispersion models both provide important information to help understand the emissions of volatile organic compounds (VOCs) and develop effective management strategies. In this study, differences between the predicted concentrations of two models and the associated impacts on the estimated health risks due to different theories behind two models were investigated. Two petrochemical industrial complexes in Kaohsiung city of southern Taiwan were selected as the sites for this comparison. Although the study compares the approaches by applying the methods to this specific area, the results are expected to be adopted for other areas or industries. Ninety-nine VOC concentrations at eight monitoring sites were analyzed, with the effects of diurnal temperature and seasonal humidity variations being considered. The Chemical Mass Balance (CMB) receptor model was used for source apportionment, while the Industrial Source Complex (ISC) dispersion model was used to predict the VOC concentrations at receptor sites. In the results of receptor modeling, 54% ± 11% and 49% ± 20% of the monitored concentrations were contributed by process emissions in two complexes, whereas the numbers increased to 78% ± 41% and 64% ± 44% in the results of dispersion modeling. Significant differences were observed between two model predictions (p < 0.05). The receptor model was more reproducible given the smaller variances of its results. The effect of seasonal humidity variation on two model predictions was not negligible. Similar findings were observed given that the cancer and non-cancer risks estimated by the receptor model were lower but more reproducible. The adverse health risks estimated by the dispersion model exceeded and were 75.3%-132.4% of the values estimated by using the monitored data, whereas the percentages were lowered to the range from 27.4% to 53.8% when the prediction was performed by using the receptor model. As the results of different models could be

  14. Clinical use of the activated partial thromboplastin time and prothrombin time for screening: a review of the literature and current guidelines for testing.

    PubMed

    Levy, Jerrold H; Szlam, Fania; Wolberg, Alisa S; Winkler, Anne

    2014-09-01

    Although the activated partial thromboplastin time, prothrombin time, and international normalized ratio are widely used in routine preoperative testing, these hemostatic tests are not reliable predictors of perioperative bleeding in patients without known bleeding risk factors. In contrast, a preoperative bleeding history and physical examination are usually obtained in an attempt to identify important bleeding risk factors. However, these coagulation tests are used extensively for monitoring anticoagulation with different pharmacologic agents.

  15. Clinical impact of factor V Leiden, prothrombin G20210A, and MTHFR C677T mutations among sickle cell disease patients of Central India.

    PubMed

    Nishank, Sudhansu Sekhar; Singh, Mendi Prema Shyam Sunder; Yadav, Rajiv

    2013-11-01

    It is known that patients with sickle cell disease (SCD) present activation of the blood coagulation and fibrinolytic systems, especially during vaso-occlusive crises and also during the steady state of the disease. We determined whether the presence of the factor prothrombin gene G20210A variant, factor V gene G1691A mutation (factor V Leiden), and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphisms may be risk factors for vascular complications in individuals with SCD. The study involved 150 patients with sickle cell anemia and 150 healthy controls of Central India. Genotyping of three thrombophilic mutations was carried out by PCR-RFLP methods using MnlI, Hind III, and Hinf I, respectively, for factor V Leiden, prothrombin, and MTHFR mutations. Patients with SCD had significantly higher prevalence of mutant variants of MTHFR gene (28.0% heterozygotes and 14.6% homozygotes) and FVL gene (14.6% heterozygotes) as compared to normal/control individuals, but complete absence of mutant variants of prothrombin gene. The patients with SCD having mutant variants of MTHFR and FVL genes showed higher incidence of pain in chest, abdomen, and bone joints along with early age of onset of clinical manifestations as well as frequent dependence on blood transfusion than those patients with SCD having wild variants of these thrombotic genes. As compared to control subjects, SCD individuals having mutant variants of FVL and MTHFR genes had significant association with higher levels of prothrombin fragment (F1+2), D-dimer, thrombin-antithrombin (TAT), and lower level of protein C. MTHFR C677T and FVL G1691A polymorphisms may be risk factors for increased vascular complications in patient with SCD. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Factor IX and prothrombin in amniotic fluid and fetal plasma: constraints on prenatal diagnosis of hemophilia B and evidence of proteolysis.

    PubMed

    Thompson, A R

    1984-10-01

    Potential limitations of prenatal diagnosis of hemophilia B, as compared to hemophilia A, include (1) occurrence of far more frequent defects with abnormal circulating antigen, (2) lower levels of factor IX in fetal plasma at 16 to 20 weeks gestation, and (3) the presence of factor IX antigen in amniotic fluid. In addition, proteolysis could occur, especially with amniotic fluid contamination of fetal plasma. A sensitive polyclonal immunoradiometric assay for factor IX antigen was used to characterize the range of levels in amniotic fluids and fetal plasma samples. To assess for altered forms, factor IX species were compared to those of a homologous clotting factor, prothrombin. Fourteen postmortem abortus blood samples from fetuses of 14 to 23 weeks gestation had factor IX antigen levels that averaged 5.1 U/dL and ranged from 1.7 to 15 U/dL. Amniotic fluid factor IX antigen averaged 2.9 U/dL, with a range from 1.4 to 8.5 U/dL in 19 separate amniocentesis samples. Thus, in a male fetus at risk of hemophilia B and with a low circulating level of gene product, mixture of fetal plasma with amniotic fluid could severely limit prenatal diagnosis, assuming that the amniotic fluid factor IX is of maternal origin. Despite rapid processing of amniotic fluid samples, the prothrombin was extensively cleaved, suggesting that it had been activated in vivo. On gel electrophoresis of amniotic fluid samples, however, factor IX was only minimally cleaved. In the postmortem fetal blood specimens, prothrombin was partially cleaved. On crossed-immunoelectrophoresis, fetal plasma prothrombin showed decreased migration in calcium, compared to EDTA, indicative of mature gamma-glutamyl carboxylation. The latter presumably resulted from fetal hepatic synthesis.

  17. Long-Term Supplementation with Beta Serum Concentrate (BSC), a Complex of Milk Lipids, during Post-Natal Brain Development Improves Memory in Rats.

    PubMed

    Guan, Jian; MacGibbon, Alastair; Fong, Bertram; Zhang, Rong; Liu, Karen; Rowan, Angela; McJarrow, Paul

    2015-06-05

    We have previously reported that the supplementation of ganglioside-enriched complex-milk-lipids improves cognitive function and that a phospholipid-enriched complex-milk-lipid prevents age-related cognitive decline in rats. This current study evaluated the effects of post-natal supplementation of ganglioside- and phospholipid-enriched complex-milk-lipids beta serum concentrate (BSC) on cognitive function in young rats. The diet of male rats was supplemented with either gels formulated BSC (n = 16) or blank gels (n = 16) from post-natal day 10 to day 70. Memory and anxiety-like behaviors were evaluated using the Morris water maze, dark-light boxes, and elevated plus maze tests. Neuroplasticity and white matter were measured using immunohistochemical staining. The overall performance in seven-day acquisition trials was similar between the groups. Compared with the control group, BSC supplementation reduced the latency to the platform during day one of the acquisition tests. Supplementation improved memory by showing reduced latency and improved path efficiency to the platform quadrant, and smaller initial heading error from the platform zone. Supplemented rats showed an increase in striatal dopamine terminals and hippocampal glutamate receptors. Thus BSC supplementation during post-natal brain development improved learning and memory, independent from anxiety. The moderately enhanced neuroplasticity in dopamine and glutamate may be biological changes underlying the improved cognitive function.

  18. The localization of a vitamin K-induced modification in an N-terminal fragment of human prothrombin

    PubMed Central

    Skotland, Tore; Holm, Turid; Østerud, Bjarne; Flengsrud, Ragnar; Prydz, Hans

    1974-01-01

    1. The N-terminal fragment (PF-I) split off from prothrombin during coagulation was purified to homogeneity from human serum. 2. The apparent molecular weight is 27000±2000 in sodium dodecyl sulphate–polyacrylamide-gel electrophoresis, whereas a value of about 19600 is obtained by calculation based on amino acid and carbohydrate analyses. The N-terminal sequence is an Ala-Asx bond. The fragment contains about 16% carbohydrate, binds phospholipids in the presence of Ca2+ and is adsorbed to BaSO4. The pKa of its BaSO4-binding group(s) is 3.1–3.5. 3. By CNBr cleavage of fragment PF-I two peptides (C-1 and C-2) were obtained with molecular weights of about 5900 (C-2) and 12400 (C-1) on the basis of amino acid and carbohydrate analyses. Only the smaller (N-terminal) peptide is adsorbed to BaSO4 and, since the ability of the whole protein to bind to BaSO4 is known to be absent in samples obtained from patients treated with vitamin K antagonists, this peptide probably contains the site of a modification to the structure of the protein which occurs during biosynthesis and depends on vitamin K. This peptide does not contain hexosamine or sialic acid. ImagesFig. 2. PMID:4219283

  19. Clinically relevant differences in prothrombin time and INR values related to blood sample collection in plastic vs glass tubes.

    PubMed

    Fiebig, Eberhard W; Etzell, Joan E; Ng, Valerie L

    2005-12-01

    We compared prothrombin times (PTs) and international normalized ratios (INRs) for blood samples drawn into plastic vs glass collection tubes. We collected 60 venous blood samples into 4.5-mL glass and 2 plastic tubes (2.7 and 3.5 mL). An additional 153 samples, including 63 from warfarin-anticoagulated patients, were collected only in glass and 2.7-mL plastic tubes. The PTs and INRs were determined following routine laboratory procedures. A subset of 35 frozen aliquot samples was analyzed with a different instrument-reagent combination. The PTs and INRs for samples in plastic tubes were significantly lower than for samples in glass tubes. The mean INR differences increased with INR magnitude from approximately -0.1 (INR, 1.5) to -0.7 (INR, 4.5). Of the plastic tube INRs, 50% were more than 10% lower than INRs from samples collected in glass tubes. Therapeutic monitoring based on plastic-tube INRs could result in higher doses of warfarin.

  20. Clinical evaluation of whole blood prothrombin time (PT) and international normalized ratio (INR) using a Laser Speckle Rheology sensor.

    PubMed

    Tripathi, Markandey M; Egawa, Satoru; Wirth, Alexandra G; Tshikudi, Diane M; Van Cott, Elizabeth M; Nadkarni, Seemantini K

    2017-08-23

    Prothrombin time (PT) and the associated international normalized ratio (INR) are routinely tested to assess the risk of bleeding or thrombosis and to monitor response to anticoagulant therapy in patients. To measure PT/INR, conventional coagulation testing (CCT) is performed, which is time-consuming and requires the separation of cellular components from whole blood. Here, we report on a portable and battery-operated optical sensor that can rapidly quantify PT/INR within seconds by measuring alterations in the viscoelastic properties of a drop of whole blood following activation of coagulation with thromboplastin. In this study, PT/INR values were measured in 60 patients using the optical sensor and compared with the corresponding CCT values. Our results report a close correlation and high concordance between PT/INR measured using the two approaches. These findings confirm the accuracy of our optical sensing approach for rapid PT/INR testing in whole blood and highlight the potential for use at the point-of-care or for patient self-testing.

  1. Evaluation of prothrombin time and activated partial thromboplastin time in hypertensive patients attending a tertiary hospital in calabar, Nigeria.

    PubMed

    Nnenna Adaeze, Nnamani; Uchenna Emeribe, Anthony; Abdullahi Nasiru, Idris; Babayo, Adamu; Uko, Emmanuel K

    2014-01-01

    Introduction. Several biomedical findings have established the effects of hypertension on haemostasis and roles of blood coagulation products in the clinical course of hypertension. Methods. This cross-sectional study aimed at determining effects of hypertension on prothrombin time (PT) and activated partial thromboplastin time (APTT) in hypertensive patients in comparison with normotensive subjects attending a tertiary hospital in Calabar. Forty-two (42) hypertensive patients and thirty-nine (39) normotensive control subjects were investigated for PT and APTT using Quick one-stage methods. Results. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) correlated positively with APTT (r = 0.3072, r = 0.4988; P < 0.05) in hypertensive patients. DBP, SBP, PT, and APTT were significantly higher in hypertensive patients when compared to normotensive subjects (P < 0.05). DBP correlated negatively with duration of illness (r = -0.3097; P < 0.05) in hypertensive patients and positively with age of normotensive subjects (r = 0.3523; P < 0.05). Conclusion. The results obtained indicated that measurements of PT and APTT may serve as indices for evaluating hemostatic abnormalities in hypertensive patients and guide for antihypertensive therapy. However, to have better understanding of hemostatic activities in hypertension, it is recommended to conduct D-dimer, platelet factors, and protein assays.

  2. Evaluation of prothrombin time and activated partial thromboplastin time mixing studies using an estimated factor correction method.

    PubMed

    Chen, Jian; Phillips, Bonnie; Chandler, Wayne L

    2016-01-01

    Mixing studies for prolonged prothrombin time (PT)/activated partial thromboplastin time (aPTT) are used to estimate whether the prolongation is due to an inhibitor or factor deficiency. We propose a new method of mixing study interpretation based on estimation of average factor level changes. Factor level vs. PT/aPTT curves were prepared for single factor, vitamin K-dependent factor, and all factor deficiencies. These curves were used to predict the factor level in the sample and the correction needed to differentiate deficiencies from inhibitors. We compared this estimated factor correction (EFC) method to normal range, percentage correction, and Rosner index. For a given factor level, multiple factor deficiencies prolonged the PT/aPTT more than single factor deficiency, necessitating different thresholds for defining correction on mixing studies. The EFC method was superior to other the correction methods, correctly identifying 38 of 39 known inhibitors, single and multiple factor deficiencies, and correctly identifying inhibitor vs. deficiency in 50 of 59 patient samples. In 99 adult patient mixing studies over 18 months, 30% showed deficiency only, 30% inhibitor only, whereas 40% showed evidence of both. The EFC method for PT/aPTT mixing study interpretation was more accurate than the comparison methods at determining deficiency versus inhibitor.

  3. Possible incorrect genotyping of heterozygous factor V Leiden and Prothrombin 20210 gene mutations by the GeneXpert assay.

    PubMed

    Marturano, Alessandro; Bury, Loredana; Gresele, Paolo

    2014-08-05

    The GeneXpert analyzer is a hands-off system for the detection of Factor V Leiden and of Prothrombin G20210A (GPRO) gene thrombophilic mutations. Although the system is efficient and easy to use, we report the rare possibility of incorrect genotyping. 1648 samples were evaluated using the GeneXpert HemosIL Factor II and Factor V assay: 1319 were freshly analyzed while 329 were frozen, thawed and diluted with saline prior to analysis to avoid clogging of the instrument syringe. Two samples, both heterozygous, one for the factor V Leiden and the other for the GPRO gene, were incorrectly genotyped as homozygous for the relative mutation. Inspection of the Ct values and amplification curves and genotyping with PCR revealed the correct genotype as heterozygous for factor V Leiden and GPRO mutation. The GeneXpert HemosIL Factor II and Factor V assay is an automated, fast genotyping assay requiring almost no sample manipulation, advantageous characteristics if compared with other PCR-based methods. However, an inattentive use of it can generate incorrect diagnosis. A careful handling of the sample, in particular correct dilution of frozen/thawed samples before analysis, and the inspection of the amplification curves and Ct values are required to avoid artifacts. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Structure of the propeptide of prothrombin containing the. gamma. -carboxylation recognition site determined by two-dimensional NMR spectroscopy

    SciTech Connect

    Sanford, D.G.; Sudmeier, J.L.; Bachovchin, W.W.; Kanagy, C.; Furie, B.C.; Furie, B. )

    1991-10-15

    The propeptides of the vitamin K dependent blood clotting and regulatory proteins contain a {gamma}-carboxylation recognition site that directs precursor forms of these proteins for posttranslational {gamma}-carboxylation. Peptides corresponding to the propeptide of prothrombin were synthesized and examined by circular dichroism (CD) and nuclear magnetic resonance spectroscopy (NMR). CD spectra indicate that these peptides have little or no secondary structure in aqueous solutions but that the addition of trifluoroethanol induces or stabilizes a structure containing {alpha}-helical character. The maximum helical content occurs at 35-40% trifluoroethanol. This trifluoroethanol-stabilized structure was solved by two-dimensional NMR spectroscopy. The NMR results demonstrate that residues {minus}13 to {minus}3 form an amphipathic {alpha}-helix. NMR spectra indicate that a similar structure is present at 5C, in the absence of trifluoroethanol. Of the residues previously implicated in defining the {gamma}-carboxylation recognition site, four residues ({minus}18, {minus}17, {minus}16, and {minus}15) are adjacent to the helical region and one residue ({minus}10) is located within the helix. The potential role of the amphipathic {alpha}-helix in the {gamma}-carboxylation recognition site is discussed.

  5. Anti-inflammatory effect of a human prothrombin fragment-2-derived peptide, NSA9, in EOC2 microglia

    SciTech Connect

    Kim, Ji Yeon; Kim, Tae Hyong; Kim, Soung Soo

    2008-04-11

    Pro-inflammatory mediators, such as nitric oxide (NO), prostaglandin E{sub 2} (PGE{sub 2}), and several cytokines (tumor necrosis factor (TNF)-{alpha}, interleukin (IL)-1{beta}, and IL-6) are responsible for central nervous system (CNS) injuries that include ischemia, Alzheimer's disease, and neural death. Inhibition of these pro-inflammatory mediators would be an effective therapy to reduce the progression of neurodegenerative diseases. In this study, we examined the anti-inflammatory effects of a human prothrombin fragment-2-derived peptide, NSA9 (NSAVQLVEN), on the production of pro-inflammatory mediators in lipopolysaccharide (LPS)-activated brain microglia. NSA9 significantly inhibited the release of NO, PGE{sub 2}, and pro-inflammatory cytokines in a dose-dependent manner. Furthermore, NSA9 reduced the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 mRNA and protein, which control the production of NO and PGE{sub 2}, respectively. Moreover, NSA9 suppressed the LPS-induced nuclear translocation and activation of nuclear factor-{kappa}B (NF-{kappa}B). These results suggest that NSA9 strongly inhibits the pro-inflammatory responses of microglia through the modulation of NF-{kappa}B activity.

  6. The frequency of factor V Leiden and prothrombin G20210A mutations in Slovak and Roma (Gypsy) ethnic group of Eastern Slovakia.

    PubMed

    Bôžiková, Alexandra; Gabriková, Dana; Sovičová, Adriana; Behulová, Regina; Mačeková, Soňa; Boroňová, Iveta; Petrejčíková, Eva; Soták, Miroslav; Bernasovská, Jarmila; Bernasovský, Ivan

    2012-10-01

    Factor V Leiden and prothrombin G20210A are the two most prevalent causes of inherited thrombophilia. The prevalence of these mutations varies widely in healthy Caucasian population. The aim of our study was to determine the frequency of factor V Leiden and prothrombin G20210A mutations in Slovak and Roma ethnic group from Eastern Slovakia. We analyzed 540 asymptomatic individuals (269 individuals of Slovak ethnicity and 271 individuals of Roma ethnicity) by real-time PCR method. The detected allele frequencies were 2.97 versus 6.64 % for factor V Leiden (p = 0.0049), and 0.74 versus 0.92 % for prothrombin mutation (p = 0.7463) in Slovak and Roma population, respectively. The Roma ethnic group had significantly higher prevalence of factor V Leiden mutation when compared to Slovak ethnic group. The allele frequency of factor V Leiden in ethnic Romanies from Eastern Slovakia was one of the highest in Europe. Our results confirm an uneven geographical and ethnic distribution of factor V Leiden.

  7. Near infrared-red models for the remote estimation of chlorophyll- a concentration in optically complex turbid productive waters: From in situ measurements to aerial imagery

    NASA Astrophysics Data System (ADS)

    Gurlin, Daniela

    Today the water quality of many inland and coastal waters is compromised by cultural eutrophication in consequence of increased human agricultural and industrial activities and remote sensing is widely applied to monitor the trophic state of these waters. This study explores near infrared-red models for the remote estimation of chlorophyll-a concentration in turbid productive waters and compares several near infrared-red models developed within the last 35 years. Three of these near infrared-red models were calibrated for a dataset with chlorophyll-a concentrations from 2.3 to 81.2 mg m -3 and validated for independent and statistically significantly different datasets with chlorophyll-a concentrations from 4.0 to 95.5 mg m-3 and 4.0 to 24.2 mg m-3 for the spectral bands of the MEdium Resolution Imaging Spectrometer (MERIS) and Moderate-resolution Imaging Spectroradiometer (MODIS). The developed MERIS two-band algorithm estimated chlorophyll-a concentrations from 4.0 to 24.2 mg m-3, which are typical for many inland and coastal waters, very accurately with a mean absolute error 1.2 mg m-3. These results indicate a high potential of the simple MERIS two-band algorithm for the reliable estimation of chlorophyll-a concentration without any reduction in accuracy compared to more complex algorithms, even though more research seems required to analyze the sensitivity of this algorithm to differences in the chlorophyll-a specific absorption coefficient of phytoplankton. Three near infrared-red models were calibrated and validated for a smaller dataset of atmospherically corrected multi-temporal aerial imagery collected by the hyperspectral airborne imaging spectrometer for applications (AisaEAGLE). The developed algorithms successfully captured the spatial and temporal variability of the chlorophyll-a concentrations and estimated chlorophyll- a concentrations from 2.3 to 81.2 mg m-3 with mean absolute errors from 4.4 mg m-3 for the AISA two band algorithm to 5.2 mg m-3

  8. Concentrations, profiles, and estimated human exposures for polychlorinated dibenzo-p-dioxins and dibenzofurans from electronic waste recycling facilities and a chemical industrial complex in Eastern China

    SciTech Connect

    Ma, J.; Kannan, K.; Cheng, J.; Horii, Y.; Wu, Q.; Wang, W.

    2008-11-15

    Electronic shredder waste and dust from e-waste facilities, and leaves and surface soil collected in the vicinity of a large scale e-waste recycling facility in Taizhou, Eastern China, were analyzed for total dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) including 2,3,7,8-substituted congeners. We also determined PCDD/Fs in surface agricultural soils from several provinces in China for comparison with soils from e-waste facilities. Concentrations of total PCDD/Fs were high in all of the matrices analyzed and ranged from 30.9 to 11,400 pg/g for shredder waste, 3460 to 9820 pg/g dry weight for leaves, 2560 to 148,000 pg/g dry weight for workshop-floor dust, and 854 to 10200 pg/g dry weight for soils. We also analyzed surface soils from a chemical industrial complex (a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant) in Shanghai. Concentrations of total PCDD/Fs in surface soil from the chemical industrial complex were lower than the concentrations found in soils from e-waste recycling plants, but higher than the concentrations found in agricultural soils. Agricultural soils from six cities in China contained low levels of total PCDD/Fs. Profiles of dioxin toxic equivalents (TEQs) of 2,3,7,8-PCDD/Fs in soils from e-waste facilities in Taizhou differed from the profiles found in agricultural soils. The estimated daily intakes of TEQs of PCDD/Fs via soil/dust ingestion and dermal exposure were 2 orders of magnitude higher in people at e-waste recycling facilities than in people at the chemical industrial site, implying greater health risk for humans from dioxin exposures at e-waste recycling facilities. The calculated TEQ exposures for e-waste workers from dust and soil ingestion alone were 2-3 orders of magnitude greater than the exposures from soils in reference locations. 37 refs., 1 fig., 2 tabs.

  9. Application of a UV-Vis submersible probe for capturing changes in DOC concentrations across a mire complex during the snowmelt and summer periods

    NASA Astrophysics Data System (ADS)

    Avagyan, Armine; Runkle, Benjamin; Kutzbach, Lars

    2013-04-01

    An accurate quantification of dissolved organic carbon (DOC) is crucial for understanding changes in water resources under the influence of climate, land use and urbanization. However, the conventionally used methods do not allow high frequency in situ analyses in remote or hostile environments (e.g., industrial wastewater or during environmental high-flow events, such as snowmelt or floods). In particular, missing measurements during the snowmelt period in landscapes of the boreal region can lead to significant miscalculations in regional carbon budgets. Therefore, the aim of the study was to test the performance of a portable, submersible UV-Vis spectrophotometer (spectro::lyser, s::can Messtechnik GmbH, Austria) during the snowmelt period in a boreal mire-forest catchment, and to provide a conceptual understanding of the spatial and temporal dynamics of DOC concentrations during and after snowmelt. During 2011, water samples were collected from the near-pristine Ust-Pojeg mire complex in northwestern Russia (61° 56'N, 50° 13'E). Sampling started during the spring snowmelt period and continued until late fall. The mire presented a mosaic of different landscape units. The mire consisted of minerogeous (fen), ombrogenous (bog), and transitional forest-mire (lagg) zones. Water samples were taken from the surface across the mire (22 points at 50-m intervals). DOC concentrations were analyzed directly at the study site using a portable, submersible UV-Vis spectrophotometer, which uses high-resolution absorbance measurements over the wavelength range 200-742.5 nm at 2.5-nm intervals as a proxy for DOC content. Because the DOC composition of fluids varies by site, a local calibration replaced the default settings of the spectro::lyser (Global Calibration) to enhance the accuracy of the measurements. To evaluate the local calibration and correct for drift, the same samples (n = 157) were additionally analyzed using the wet persulfate oxidation method (O

  10. Monitoring of ractopamine concentration in the mixture of this feed additive with vitamin mineral complex and with swine feed by HPLC.

    PubMed

    Freire, Ellen Figueiredo; Borges, Keyller Bastos; Tanimoto, Hélio; Nogueira, Raquel Tassara; Bertolini, Lucimara Cristiane Toso; de Gaitani, Cristiane Masetto

    2013-01-01

    Ractopamine (RAC) analysis at all stages in the feed chain until its final mixing into swine feed is necessary to ensure the safety of all meat consumers and to decrease waste and the cost of supplementation of feed. Two suitable HPLC methods were developed and validated for RAC determination in vitamin mineral complex (VMC) and in swine feed. Both methods employed reverse-phase (C18 column at 40°C) and isocratic elution, but with some modifications to the methods. Validation parameters, such as selectivity, linearity, precision, trueness and robustness, were shown to be within the acceptable range. Therefore, the developed methods can be successfully applied for the monitoring of RAC concentrations in samples of VMC and swine feed ensuring economy to producers and security to consumers of swine meat.

  11. Light and low-CO2-dependent LCIB-LCIC complex localization in the chloroplast supports the carbon-concentrating mechanism in Chlamydomonas reinhardtii.

    PubMed

    Yamano, Takashi; Tsujikawa, Tomoki; Hatano, Kyoko; Ozawa, Shin-Ichiro; Takahashi, Yuichiro; Fukuzawa, Hideya

    2010-09-01

    The carbon-concentrating mechanism (CCM) is essential to support photosynthesis under CO2-limiting conditions in aquatic photosynthetic organisms, including the green alga Chlamydomonas reinhardtii. The CCM is assumed to be comprised of inorganic carbon transport systems that, in conjunction with carbonic anhydrases, maintain high levels of CO2 around ribulose-1, 5-bisphosphate carboxylase/oxygenase in a specific compartment called the pyrenoid. A set of transcripts up-regulated during the induction of the CCM was identified previously and designated as low-CO2 (LC)-inducible genes. Although the functional importance of one of these LC-inducible genes, LciB, has been shown recently, the biochemical properties and detailed subcellular localization of its product LCIB remain to be elucidated. Here, using yeast two-hybrid, immunoprecipitation and mass spectrometry analyses we provide evidence to demonstrate that LCIB interacts with the LCIB homologous protein LCIC in yeast and in vivo. We also show that LCIB and LCIC are co-localized in the vicinity of the pyrenoid under LC conditions in the light, forming a hexamer complex of approximately 350 kDa, as estimated by gel filtration chromatography. LCIB localization around the pyrenoid was dependent on light illumination and LC conditions during active operation of the CCM. In contrast, in the dark or under high-CO2 conditions when the CCM was inactive, LCIB immediately diffused away from the pyrenoid. Based on these observations, we discuss possible functions of the LCIB-LCIC complex in the CCM.

  12. A Computer-Controlled, MR-compatible Foot-Pedal Device to Study Dynamics of the Muscle Tendon Complex under Isometric, Concentric and Eccentric Contractions

    PubMed Central

    Sinha, Shantanu; Shin, David D.; Hodgson, John A.; Kinugasa, Ryuta; Edgerton, V. Reggie

    2013-01-01

    Purpose To design a computer-controlled, MR compatible foot pedal device that allows in vivo mapping of changes in morphology and in strain of different musculoskeletal components of the lower leg under passive, isometric, concentric and eccentric contractions. Materials and Methods A programmable servo-motor in the control room pumped hydraulic fluid to rotate a foot-pedal inside the magnet. Towards validating the performance of the device, six subjects were imaged with gated velocity-encoded phase-contrast (VE-PC) imaging to investigate dynamics of muscle and aponeurotic structures. Results Artifact-free VE-PC imaging clearly delineated different muscle compartments by differences in distribution of mechanical strains. High repeatability of contraction cycles allowed establishing that fascicles lengthened 6.1% more during passive compared to eccentric contractions. Aponeurosis separation during passive (range between three locations: −2.6~1.3 mm) and active (range: −2.4 ~1.6 mm) contractions were similar but significantly different from concentric (range: −0.9~3.3 mm), with proximal and distal regions showing mostly negative values for the first two modes, but positive for the last. Conclusion The device was sufficiently robust and artifact-free to accurately assess, using VE-PC imaging, physiologically important structure and dynamics of the musculo-tendon complex. PMID:22392816

  13. Using nitrogen concentration and isotopic composition in lichens to spatially assess the relative contribution of atmospheric nitrogen sources in complex landscapes.

    PubMed

    Pinho, P; Barros, C; Augusto, S; Pereira, M J; Máguas, C; Branquinho, C

    2017-11-01

    Reactive nitrogen (Nr) is an important driver of global change, causing alterations in ecosystem biodiversity and functionality. Environmental assessments require monitoring the emission and deposition of both the amount and types of Nr. This is especially important in heterogeneous landscapes, as different land-cover types emit particular forms of Nr to the atmosphere, which can impact ecosystems distinctively. Such assessments require high spatial resolution maps that also integrate temporal variations, and can only be feasibly achieved by using ecological indicators. Our aim was to rank land-cover types according to the amount and form of emitted atmospheric Nr in a complex landscape with multiple sources of N. To do so, we measured and mapped nitrogen concentration and isotopic composition in lichen thalli, which we then related to land-cover data. Results suggested that, at the landscape scale, intensive agriculture and urban areas were the most important sources of Nr to the atmosphere. Additionally, the ocean greatly influences Nr in land, by providing air with low Nr concentration and a unique isotopic composition. These results have important consequences for managing air pollution at the regional level, as they provide critical information for modeling Nr emission and deposition across regional as well as continental scales. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Determination of Background Uranium Concentration in the Snake River Plain Aquifer under the Idaho National Engineering and Environmental Laboratory's Radioactive Waste Management Complex

    SciTech Connect

    Molly K. Leecaster; L. Don Koeppen; Gail L. Olson

    2003-06-01

    Uranium occurs naturally in the environment and is also a contaminant that is disposed of at the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering and Environmental Laboratory. To determine whether uranium concentrations in the Snake River Plain Aquifer, which underlies the laboratory, are elevated as a result of migration of anthropogenic uranium from the Subsurface Disposal Area in the RWMC, uranium background concentrations are necessary. Guideline values are calculated for total uranium, 234U, 235U, and 238U from analytical results from up to five datasets. Three of the datasets include results of samples analyzed using isotope dilution thermal ionization mass spectrometry (ID-TIMS) and two of the datasets include results obtained using alpha spectrometry. All samples included in the statistical testing were collected from aquifer monitoring wells located within 10 miles of the RWMC. Results from ID-TIMS and alpha spectrometry are combined when the data are not statistically different. Guideline values for total uranium were calculated using four of the datasets, while guideline values for 234U were calculated using only the alpha spectrometry results (2 datasets). Data from all five datasets were used to calculate 238U guideline values. No limit is calculated for 235U because the ID-TIMS results are not useful for comparison with routine monitoring data, and the alpha spectrometry results are too close to the detection limit to be deemed accurate or reliable for calculating a 235U guideline value. All guideline values presented represent the upper 95% coverage 95% confidence tolerance limits for background concentration. If a future monitoring result is above this guideline, then the exceedance will be noted in the quarterly monitoring report and assessed with respect to other aquifer information. The guidelines (tolerance limits) for total U, 234U, and 238U are 2.75 pCi/L, 1.92 pCi/L, and 0.90 pCi/L, respectively.

  15. Triggers for β-sheet formation at the hydrophobic-hydrophilic interface: high concentration, in-plane orientational order, and metal ion complexation.

    PubMed

    Hoernke, Maria; Falenski, Jessica A; Schwieger, Christian; Koksch, Beate; Brezesinski, Gerald

    2011-12-06

    Amyloid formation plays a causative role in neurodegenerative diseases such as Alzheimer's disease or Parkinson's disease. Soluble peptides form β-sheets that subsequently rearrange into fibrils and deposit as amyloid plaques. Many parameters trigger and influence the onset of the β-sheet formation. Early stages are recently discussed to be cell-toxic. Aiming at understanding various triggers such as interactions with hydrophobic-hydrophilic interfaces and metal ion complexation and their interplay, we investigated a set of model peptides at the air-water interface. We are using a general approach to a variety of diseases such as Alzheimer's disease, Parkinson's disease, and type II diabetes that are connected to amyloid formation. Surface sensitive techniques combined with film balance measurements have been used to assess the conformation of the peptides and their orientation at the air-water interface (IR reflection-absorption spectroscopy). Additionally, the structures of the peptide layers were characterized by grazing incidence X-ray diffraction and X-ray reflectivity. The peptides adsorb to the air-water interface and immediately adopt an α-helical conformation. This helical intermediate transforms into β-sheets upon further triggering. The factors that result in β-sheet formation are dependent on the peptide sequence. In general, the interface has the strongest effect on peptide conformation compared to high concentrations or metal ions. Metal ions are able to prevent aggregation in bulk but not at the interface. At the interface, metal ion complexation has only minor effects on the peptide secondary structure, influencing the in-plane structure that is formed in two dimensions. At the air-water interface, increased concentrations or a parallel arrangement of the α-helical intermediates are the most effective triggers. This study reveals the role of various triggers for β-sheet formation and their complex interplay. Our main finding is that the

  16. Genetic Associations for Activated Partial Thromboplastin Time and Prothrombin Time, their Gene Expression Profiles, and Risk of Coronary Artery Disease

    PubMed Central

    Tang, Weihong; Schwienbacher, Christine; Lopez, Lorna M.; Ben-Shlomo, Yoav; Oudot-Mellakh, Tiphaine; Johnson, Andrew D.; Samani, Nilesh J.; Basu, Saonli; Gögele, Martin; Davies, Gail; Lowe, Gordon D.O.; Tregouet, David-Alexandre; Tan, Adrian; Pankow, James S.; Tenesa, Albert; Levy, Daniel; Volpato, Claudia B.; Rumley, Ann; Gow, Alan J.; Minelli, Cosetta; Yarnell, John W.G.; Porteous, David J.; Starr, John M.; Gallacher, John; Boerwinkle, Eric; Visscher, Peter M.; Pramstaller, Peter P.; Cushman, Mary; Emilsson, Valur; Plump, Andrew S.; Matijevic, Nena; Morange, Pierre-Emmanuel; Deary, Ian J.; Hicks, Andrew A.; Folsom, Aaron R.

    2012-01-01

    Activated partial thromboplastin time (aPTT) and prothrombin time (PT) are clinical tests commonly used to screen for coagulation-factor deficiencies. One genome-wide association study (GWAS) has been reported previously for aPTT, but no GWAS has been reported for PT. We conducted a GWAS and meta-analysis to identify genetic loci for aPTT and PT. The GWAS for aPTT was conducted in 9,240 individuals of European ancestry from the Atherosclerosis Risk in Communities (ARIC) study, and the GWAS for PT was conducted in 2,583 participants from the Genetic Study of Three Population Microisolates in South Tyrol (MICROS) and the Lothian Birth Cohorts (LBC) of 1921 and 1936. Replication was assessed in 1,041 to 3,467 individuals. For aPTT, previously reported associations with KNG1, HRG, F11, F12, and ABO were confirmed. A second independent association in ABO was identified and replicated (rs8176704, p = 4.26 × 10−24). Pooling the ARIC and replication data yielded two additional loci in F5 (rs6028, p = 3.22 × 10−9) and AGBL1 (rs2469184, p = 3.61 × 10−8). For PT, significant associations were identified and confirmed in F7 (rs561241, p = 3.71 × 10−56) and PROCR/EDEM2 (rs2295888, p = 5.25 × 10−13). Assessment of existing gene expression and coronary artery disease (CAD) databases identified associations of five of the GWAS loci with altered gene expression and two with CAD. In summary, eight genetic loci that account for ∼29% of the variance in aPTT and two loci that account for ∼14% of the variance in PT were detected and supported by functional data. PMID:22703881

  17. A performance evaluation of a novel human recombinant tissue factor prothrombin time reagent (Revohem(™) PT).

    PubMed

    Gardiner, C; Kohama, K; Patel, I; Lane, P; Dwyer, S; Machin, S J; Mackie, I J

    2017-06-12

    A new prothrombin time reagent (Revohem™ PT) based on recombinant human tissue factor produced by the silkworm-baculovirus expression system was tested. The aim of this study was to compare the performance of the new PT reagent with two widely used routine PT reagents. All testing was performed on a Sysmex CS-5100 coagulometer. Revohem(™) PT was tested for imprecision and stability using normal and abnormal lyophilized commercial control plasmas. Comparability was assessed with two widely used reagents: one containing recombinant human tissue factor (Reagent A) and the other a human placental thromboplastin (Reagent B) using a wide range of normal and abnormal plasmas and analyser-specific ISI values. Excellent between-day imprecision was obtained for Revohem(™) PT (CV <1.0%) and acceptable open-vial on-board stability over 7 days. There was good agreement between methods in samples from patients with liver disease and patients receiving warfarin and no significant differences between methods with increasing INR values. Both recombinant reagents suffered less interference from lupus anticoagulant than the placental thromboplastin. Revohem(™) PT had similar sensitivity to reagents A and B for FII, V, VII and X deficiency and demonstrated dose responsiveness to dabigatran, apixaban and rivaroxaban with steeper response curves than the comparison reagents. Revohem(™) PT showed comparable or improved performance relative to two widely used reagents and is suitable for use in warfarin control, detection of inherited factor II, V, VII and X deficiency and assessment of liver disease coagulopathy. © 2017 John Wiley & Sons Ltd.

  18. Prolonged prothrombin time after recombinant activated factor VII therapy in critically bleeding trauma patients is associated with adverse outcomes.

    PubMed

    McMullin, Neil R; Wade, Charles E; Holcomb, John B; Nielsen, Tina G; Rossaint, Rolf; Riou, Bruno; Rizoli, Sandro B; Kluger, Yoram; Choong, Philip I T; Warren, Brian; Tortella, Bartholomew J; Boffard, Kenneth D

    2010-07-01

    In trauma patients with significant hemorrhage, it is hypothesized that failure to normalize prothrombin time (PT) after recombinant activated factor VII (rFVIIa) treatment predicts poor clinical outcomes and potentially indicates a need for additional therapeutic interventions. To assess the value of PT to predict outcomes after rFVIIa or placebo therapy, we performed a post hoc analysis of data from 169 severely injured, critically bleeding trauma patients who had 1-hour postdose PT measurements from two randomized clinical trials. Baseline characteristics and outcome parameters were compared between subjects with 1-hour postdose PT >or=18 seconds and PT <18 seconds. In rFVIIa-treated subjects, prolonged postdose PT values >or=18 seconds were associated with significantly higher 24-hour mortality (60% vs. 3%; p < 0.001) and 30-day mortality, increased incidence of massive transfusion, and fewer intensive care unit-free days compared with postdose PT values <18 seconds. Recombinant rFVIIa-treated subjects with postdose PT >or=18 seconds had significantly lower baseline hemoglobin levels, fibrinogen levels, and platelet counts than subjects with postdose PT values <18 seconds even though they received similar amounts of blood products before rFVIIa dosing. Placebo-treated subjects with postdose PT >or=18 seconds had significantly increased incidence of massive transfusion, significantly decreased intensive care unit-free days, and significantly lower levels of fibrinogen and platelets at baseline compared with subjects with postdose PT values <18 seconds. The presence of prolonged PT after rFVIIa or placebo therapy was associated with poor clinical outcomes. Because subjects with postdosing PT >or=18 seconds had low levels of hemoglobin, fibrinogen, and platelets, this group may benefit from additional blood component therapy.

  19. Relationship Between Infarct Volume and Prothrombin Time-International Normalized Ratio in Ischemic Stroke Patients With Nonvalvular Atrial Fibrillation.

    PubMed

    Matsumoto, Mari; Sakaguchi, Manabu; Okazaki, Shuhei; Hashikawa, Kazuo; Takahashi, Tsutomu; Matsumoto, Masayasu; Ohtsuki, Toshiho; Shimazu, Takeshi; Yoshimine, Toshiki; Mochizuki, Hideki; Kitagawa, Kazuo

    2017-02-24

    In Japan, warfarin treatment at prothrombin time-international normalized ratio (PT-INR) of 1.60-2.60 is recommended for elderly patients with nonvalvular atrial fibrillation (NVAF). But it remains unknown whether PT-INR 1.60-1.99 has a similar effect on stroke severity as a value >2.0. The purpose of this study was to clarify the association between infarct volume and PT-INR levels.Methods and Results:The 180 patients (mean age, 76 years [SD, 10 years], 53% male) selected from 429 consecutive ischemic stroke patients admitted within 48 h of onset between 2004 and 2014 with NVAF were included. We classified them into 4 groups according to their PT-INR values on admission: no warfarin (NW), 129 patients; PT-INR <1.60 (poor control: PC), 29 patients; PT-INR 1.60-1.99 (low-intensity control: LC), 14 patients; and PT-INR ≥2.00 (high-intensity control: HC), 8 patients. Median (interquartile range: IQR) of infarct volume was 55 mL (IQR 14-175) in the NW, 42 mL (IQR 27-170) in the PC, 36 mL (IQR 6-130) in the LC, and 11 mL (IQR 0-39) in the HC groups. The infarct volume of the HC group was significantly smaller than in the other 3 groups, but no difference existed between the LC and PC groups or the LC and NW groups. Warfarin control at PT-INR of 1.60-1.99 is not effective for reducing the severity of ischemic stroke in NVAF patients.

  20. Simplified method for international normalized ratio (INR) derivation based on the prothrombin time/INR line: an international study.

    PubMed

    Poller, Leon; Ibrahim, Saied; Keown, Michelle; Pattison, Albert; Jespersen, Jørgen

    2010-10-01

    The need to perform local International Sensitivity Index (ISI) calibrations and in particular the requirement for a manual method for prothrombin time (PT) determination, have proved to be obstacles to application of the WHO scheme for PT standardization. We used international normalized ratio (INR) derived with a set of only 5 European Concerted Action on Anticoagulation (ECAA) lyophilized calibrant plasmas, certified manually by expert centers with reference thromboplastins, to determine a local PT/INR Line. We compared results of an independent set of validation plasmas with INRs from conventional ISI calibrations and with manually certified INRs. The mean certified INR of 5 lyophilized validation plasmas was 2.41 with human thromboplastin, 2.04 with bovine/combined, and 2.80 with rabbit. With 42 human reagents, the mean observed INR of the validation plasmas was 2.68 (11.2% deviation from certified INR). Deviation was reduced to 0.4% with both local ISI calibration and the PT/INR Line. Eight results based on bovine/combined thromboplastin gave an INR deviation of 4.9%, becoming 0.5% after ISI calibration and 2.4% with the PT/INR Line. Six results with rabbit reagents deviated from certified INR by 2.5%. After ISI calibration, deviation became 1.1%, and with the PT/INR Line, 0.7%. The PT/INR Line gave similar results with both linear and orthogonal regression analysis. The total proportion of validation plasmas giving INR within 10% deviation from certified values was 42.5% with uncorrected INR, which increased to 92.1% with local ISI calibration and 93.2% with the PT/INR Line. The PT/INR Line procedure with 5 ECAA calibrant plasmas successfully substitutes for local ISI calibrations in deriving reliable INRs.

  1. D-Dimer versus International Normalized Ratio of Prothrombin Time in Ischemic Stroke Patients Treated with Sufficient Warfarin.

    PubMed

    Yamamoto, Ryoo; Nakae, Yoshiharu; Tanaka, Fumiaki; Johkura, Ken

    2016-07-01

    In patients receiving chronic warfarin therapy, the international normalized ratio of prothrombin time (PT-INR) reportedly correlates with the incidence, size, severity, and outcome of ischemic stroke, and thus there are guidelines for the optimal PT-INR range that is to be maintained during secondary or primary prevention of ischemic stroke. However, the details of ischemic stroke in patients in whom an optimal PT-INR is maintained by warfarin therapy have not been thoroughly investigated. We conducted a retrospective study to determine the predictors of the size, severity, and outcome of ischemic stroke occurring in patients under chronic warfarin therapy and maintenance of an optimum PT-INR. The study group comprised 22 consecutive acute ischemic stroke patients who were receiving warfarin and whose PT-INR was within the optimal range on admission. The PT-INR and plasma D-dimer level of these patients on admission were analyzed in relation to infarction volume, National Institutes of Health Stroke Scale score on admission, and modified Rankin Scale score at discharge. PT-INR did not correlate with infarction volume, severity, or outcome. The D-dimer level correlated positively and significantly with the volume (r = .49, P < .05), severity (r = .54, P < .05), and outcome of ischemic stroke (r = .61, P < .01) and did not correlate with the PT-INR (r = -.27, P = .23). When the PT-INR is within optimal range in patients receiving chronic warfarin therapy but who suffer an ischemic stroke, the admission D-dimer level, but not PT-INR, correlates with the size, severity, and outcome of the stroke. Thus, monitoring the D-dimer level in patients receiving long-term warfarin therapy is important, regardless of whether the optimal PT-INR is maintained. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  2. Evaluation of the Steelex M600H coagulometer prothrombin time-international normalized ratio assay with Steelex test reagents

    PubMed Central

    Budak, Yasemin U.; Huysal, Kağan; Polat, Murat; Tarakçı, Gülsevil; Uçar, Hakan

    2012-01-01

    Introduction The aim of the present study was to validate prothrombin time (PT) international normalized ratio (INR) results obtained using Steelex test reagents and a Steelex coagulometer (Steelex Scientific Instrument Company, Beijing, China), in comparison with use of a well-established standard test employing Pacific Hemostasis reagents (Fisher Diagnostics, Middletown, VA, USA) and Teco Coatron A4 coagulometer (Teco Medical Instruments GmbH, Neufahrn, Germany). Materials and methods: Between- and within-day coefficients of variation (CVs) of both assays were calculated using control samples provided by the test manufacturers. Samples from 90 subjects were collected and INR values were determined in a double-blind parallel manner employing both systems. Results: The within-day coefficients of variation (CVs) in INR estimates ranged from 2.6% (INR = 1.12) to 3.1% (INR = 2.51) for the Steelex system and from 2.1% (INR = 1.09) to 1.8% (INR = 2.8) for the Pacific test; the between-day values ran from 3.4% (INR = 1.16) to 7.9% (INR = 2.64) and from 3.3% (INR = 1.1) to 2.3% (INR = 2.7), respectively. Passing-Bablok fit of the of the Steelex and Pacific methods yielded the equation: Steelex INR = 0.85 (0.79–0.91) × Pacific INR + 0.12 (−0.02–0.21), whereas the CUSUM linearity P value was < 0.01. The mean bias as determined by the Bland-Altman test was −0.156 (−0.912–0.600). Conclusion: The results obtained using Steelex reagents and the M600H coagulometer are not equivalent to those obtained using Pacific Hemostasis reagents and a Teco Coatron A4 coagulometer, at least in the therapeutic range. PMID:22384527

  3. Genetic associations for activated partial thromboplastin time and prothrombin time, their gene expression profiles, and risk of coronary artery disease.

    PubMed

    Tang, Weihong; Schwienbacher, Christine; Lopez, Lorna M; Ben-Shlomo, Yoav; Oudot-Mellakh, Tiphaine; Johnson, Andrew D; Samani, Nilesh J; Basu, Saonli; Gögele, Martin; Davies, Gail; Lowe, Gordon D O; Tregouet, David-Alexandre; Tan, Adrian; Pankow, James S; Tenesa, Albert; Levy, Daniel; Volpato, Claudia B; Rumley, Ann; Gow, Alan J; Minelli, Cosetta; Yarnell, John W G; Porteous, David J; Starr, John M; Gallacher, John; Boerwinkle, Eric; Visscher, Peter M; Pramstaller, Peter P; Cushman, Mary; Emilsson, Valur; Plump, Andrew S; Matijevic, Nena; Morange, Pierre-Emmanuel; Deary, Ian J; Hicks, Andrew A; Folsom, Aaron R

    2012-07-13

    Activated partial thromboplastin time (aPTT) and prothrombin time (PT) are clinical tests commonly used to screen for coagulation-factor deficiencies. One genome-wide association study (GWAS) has been reported previously for aPTT, but no GWAS has been reported for PT. We conducted a GWAS and meta-analysis to identify genetic loci for aPTT and PT. The GWAS for aPTT was conducted in 9,240 individuals of European ancestry from the Atherosclerosis Risk in Communities (ARIC) study, and the GWAS for PT was conducted in 2,583 participants from the Genetic Study of Three Population Microisolates in South Tyrol (MICROS) and the Lothian Birth Cohorts (LBC) of 1921 and 1936. Replication was assessed in 1,041 to 3,467 individuals. For aPTT, previously reported associations with KNG1, HRG, F11, F12, and ABO were confirmed. A second independent association in ABO was identified and replicated (rs8176704, p = 4.26 × 10(-24)). Pooling the ARIC and replication data yielded two additional loci in F5 (rs6028, p = 3.22 × 10(-9)) and AGBL1 (rs2469184, p = 3.61 × 10(-8)). For PT, significant associations were identified and confirmed in F7 (rs561241, p = 3.71 × 10(-56)) and PROCR/EDEM2 (rs2295888, p = 5.25 × 10(-13)). Assessment of existing gene expression and coronary artery disease (CAD) databases identified associations of five of the GWAS loci with altered gene expression and two with CAD. In summary, eight genetic loci that account for ∼29% of the variance in aPTT and two loci that account for ∼14% of the variance in PT were detected and supported by functional data.

  4. Factor V Leiden, prothrombin G20210A, and methylene tetrahydrofolate reductase mutations and stillbirth: the Stillbirth Collaborative Research Network.

    PubMed

    Silver, Robert M; Saade, George R; Thorsten, Vanessa; Parker, Corette B; Reddy, Uma M; Drews-Botsch, Carey; Conway, Deborah; Coustan, Donald; Dudley, Donald J; Bukowski, Radek; Rowland Hogue, Carol J; Pinar, Halit; Varner, Michael W; Goldenberg, Robert; Willinger, Marian

    2016-10-01

    An evaluation for heritable thrombophilias is recommended in the evaluation of stillbirth. However, the association between thrombophilias and stillbirth remains uncertain. We sought to assess the association between maternal and fetal/placental heritable thrombophilias and stillbirth in a population-based, case-control study in a geographically, racially, and ethnically diverse population. We conducted secondary analysis of data from the Stillbirth Collaborative Research Network, a population-based case-control study of stillbirth. Testing for factor V Leiden, prothrombin G20210A, methylene tetrahydrofolate reductase C677T and A1298C, and plasminogen activating inhibitor (PAI)-1 4G/5G mutations was done on maternal and fetal (or placental) DNA from singleton pregnancies. Data analyses were weighted for oversampling and other aspects of the design. Odds ratios (OR) were generated from univariate models regressing stillbirth/live birth status on each thrombophilia marker. Results were available for ≥1 marker in 488 stillbirths and 1342 live birth mothers and 405 stillbirths and 990 live birth fetuses. There was an increased odds of stillbirth for maternal homozygous factor V Leiden mutation (2/488; 0.4% vs 1/1380; 0.0046%; OR, 87.44; 95% confidence interval, 7.88-970.92). However, there were no significant differences in the odds of stillbirth for any other maternal thrombophilia, even after stratified analyses. Fetal 4G/4G PAI-1 (OR, 0.63; 95% confidence interval, 0.43-0.91) was associated with decreased odds of stillbirth. Other fetal thrombophilias were similar among groups. Most maternal and fetal thrombophilias were not associated with stillbirth. Maternal factor V Leiden was weakly associated with stillbirth, and the fetal PAI-1 4G/4G polymorphism was associated with live birth. Our data do not support routine testing for heritable thrombophilias as part of an evaluation for possible causes of stillbirth. Copyright © 2016. Published by Elsevier Inc.

  5. Factor V Leiden, Prothrombin and MTHFR Mutation in Patients with Preeclamsia, Intrauterine Growth Restriction and Placental Abruption.

    PubMed

    Livrinova, Vesna; Lega, Marija Hadzi; Dimcheva, Anita Hristova; Samardziski, Igor; Isjanovska, Rozalinda

    2015-12-15

    Factor V Leiden, Prothrombin and MTHFR gene mutation, could have an influence in pregnancy with adverse outcome Preeclamsia, IUGR and Placental abruption. The aim of this study is to investigate the presence of above mentioned inherited thrombophilias and its statistical significance, distribution among the complicated and normal pregnancy, and relative risk for carrier of mutation to develop preeclampsia, IUGR and placental abruption. Prospective cohort study is implemented at University Clinic for Obstetric and Gynecology in Skopje, Republic of Macedonia. The study included 109 delivered patients: 40 with preeclapmsia, 22 with IUGR, 17 with placental abruption and 30 as control group with normal pregnancy. The amount of 3 ml venous blood has been used for detection of these point mutations using ThromboStrip -Opegen, QIAGEN kit manufactured for thrombotic risk. The highest frequency was found: in the group with preeclampsia 35% were MTHFR homozygous, IUGR -MTHFR heterozygous 45%, Placental abruption- 52.9% MTHFR heterozygous, and in the control group without thrombophilia 56.7%. There were combined thrombophilia in 3 patients. There aren`t statistical significance in presence of thrombophilia among groups (p > 0.05). Statistical significance (p < 0.05) was found between carriers of MTHFR homozygous in preeclampsia and group with placental abruption and control group. Relative risk in IUGR group for MTHFR homozygous was 5.54 (1.37

  6. Homocysteine and prothrombin fragment 1+2 levels in patients with veno-occlusive disease after stem cell transplantation.

    PubMed

    Gerecitano, John; Mathias, Clarissa; Mick, Rosemarie; Duffy, Kathleen M; Luger, Selina; Stadtmauer, Edward A; Schuster, Stephen J; Tsai, Donald; Nasta, Sunita; Berlin, Jesse; Phillips, Deborah K; High, Katherine A; Porter, David L

    2003-04-01

    Veno-occlusive disease (VOD) of the liver remains a major complication after hematopoietic stem cell transplantation (SCT). VOD is thought to develop after hepatic endothelial cells are damaged by high-dose chemotherapy or radiation, causing microthrombosis in hepatic venules. However, the precise mechanisms leading to VOD are not well defined, and a diagnosis is often difficult to establish. It is also difficult to predict which patients are most likely to develop VOD. Elevated levels of homocysteine (HC) have been associated with thrombosis, and prothrombin fragment 1 + 2 (F1 + 2) is a measurable marker for coagulation. Therefore, we performed a prospective cohort study to determine if HC or F1 + 2 levels could be used to predict the development of VOD prior to SCT, or to help establish a diagnosis of VOD in association with other clinical parameters. Plasma levels of these factors were measured before conditioning and serially for 21 days after SCT in 42 consecutive patients undergoing SCT. Eleven of 26 allogeneic SCT recipients developed VOD, whereas no autologous SCT recipient (n = 16) developed VOD (p = 0.008). In patients who developed VOD, HC levels were consistently higher than those seen in non-VOD patients after day 7 of SCT. Patients with VOD also had higher levels of F1 + 2 after SCT, although this marker was less consistently elevated over time. A logistic regression model that evaluated all serial measures of HC and F1 + 2 showed a moderate sensitivity and specificity in diagnosing VOD in allogeneic SCT patients, but neither marker was useful to predict development of VOD when tested prior to SCT.

  7. Factor V Leiden, Prothrombin and MTHFR Mutation in Patients with Preeclamsia, Intrauterine Growth Restriction and Placental Abruption

    PubMed Central

    Livrinova, Vesna; Lega, Marija Hadzi; Dimcheva, Anita Hristova; Samardziski, Igor; Isjanovska, Rozalinda

    2015-01-01

    BACKGROUND: Factor V Leiden, Prothrombin and MTHFR gene mutation, could have an influence in pregnancy with adverse outcome Preeclamsia, IUGR and Placental abruption. AIM: The aim of this study is to investigate the presence of above mentioned inherited thrombophilias and its statistical significance, distribution among the complicated and normal pregnancy, and relative risk for carrier of mutation to develop preeclampsia, IUGR and placental abruption. MATERIAL AND METHODS: Prospective cohort study is implemented at University Clinic for Obstetric and Gynecology in Skopje, Republic of Macedonia. The study included 109 delivered patients: 40 with preeclapmsia, 22 with IUGR, 17 with placental abruption and 30 as control group with normal pregnancy. The amount of 3 ml venous blood has been used for detection of these point mutations using ThromboStrip -Opegen, QIAGEN kit manufactured for thrombotic risk. RESULTS: The highest frequency was found: in the group with preeclampsia 35% were MTHFR homozygous, IUGR -MTHFR heterozygous 45%, Placental abruption- 52.9% MTHFR heterozygous, and in the control group without thrombophilia 56.7%. There were combined thrombophilia in 3 patients. There aren`t statistical significance in presence of thrombophilia among groups (p > 0.05). Statistical significance (p < 0.05) was found between carriers of MTHFR homozygous in preeclampsia and group with placental abruption and control group. Relative risk in IUGR group for MTHFR homozygous was 5.54 (1.37

  8. Plasminogen activator inhibitor-1 4G/5G polymorphism, factor V Leiden, prothrombin mutations and the risk of VTE recurrence.

    PubMed

    Sundquist, Kristina; Wang, Xiao; Svensson, Peter J; Sundquist, Jan; Hedelius, Anna; Larsson Lönn, Sara; Zöller, Bengt; Memon, Ashfaque A

    2015-11-25

    Plasminogen-activator inhibitor (PAI)-1 is an important inhibitor of the plasminogen/plasmin system. PAI-1 levels are influenced by the 4G/5G polymorphism in the PAI-1 promoter. We investigated the relationship between the PAI-1 polymorphism and VTE recurrence, and its possible modification by factor V Leiden (FVL) and prothrombin (PTM) mutations. Patients (n=1,069) from the Malmö Thrombophilia Study were followed from discontinuation of anticoagulant treatment until diagnosis of VTE recurrence or the end of the study (maximum follow-up 9.8 years). One hundred twenty-seven patients (11.9 %) had VTE recurrence. PAI-1 was genotyped by TaqMan PCR. Cox regression analysis adjusted for age, sex and acquired risk factors of VTE showed no evidence of an association between PAI-1 genotype and risk of VTE recurrence in the study population as a whole. However, by including an interaction term in the analysis we showed that FVL but not PTM modified the effect of PAI-1 genotype: patients with the 4G allele plus FVL had a higher risk of VTE recurrence [hazard ratio (HR) =2.3, 95 % confidence interval (CI) =1.5-3.3] compared to patients with the 4G allele but no FVL (reference group) or FVL irrespective of PAI-1 genotype (HR=1.8, 95 % CI=1.3-2.5). Compared to reference group, 5G allele irrespective of FVL was associated with lower risk of VTE recurrence only when compared with 4G allele together with FVL. In conclusion, FVL has a modifying effect on PAI-1 polymorphism in relation to risk of VTE recurrence. The role of PAI-1 polymorphism as a risk factor of recurrent VTE may be FVL dependent.

  9. Prothrombin activation fragment 1 + 2 as a marker of coagulation activation in cord blood collection for banking.

    PubMed

    Juutistenaho, S; Vahtera, E; Aranko, K; Kekomäki, R

    2010-08-01

    There have been efforts to increase the quality of cord blood (CB) collections aimed at banking and transplantation. Yet, the effect of CB collection techniques on haemostatic activation is scarcely studied, despite the unique nature of the neonatal haemostatic system. The aim of this study was to explore coagulation system and platelet (PLT) activation during CB collection at a national CB bank. At three time points over a 9-year period (in 1998, 2000 and 2006), CB collections were assessed to evaluate the collection process during bank setup and changes in procedures. Thrombin generation and PLT activation were assessed with prothrombin activation fragment 1 + 2 (F1 + 2) and PLT factor 4 (PF4), respectively. The median F1 + 2 level was 2.8 nmol L(-1) in 1998 (n = 11), 0.7 nmol L(-1) in 2000 (n = 10) and 0.7 nmol L(-1) in 2006 (n = 6), the decrease being statistically significant (1998 vs 2000, P < 0.001; 1998 vs 2006, P = 0.01). The median PF4 level was 117 IU mL(-1) in 1998 and 104 IU mL(-1) in 2000. PF4 was not measured in 2006. The level of F1 + 2 correlated with that of PF4 (n = 21; Spearman's Rho = 0.59, P = 0.006). Haemostatic activation, assessed as a part of CB bank process control, decreased from the first to the subsequent sample series. F1 + 2 may be a candidate for quality control in CB banking; however, further studies are needed to optimise the analyses and to assess the effect of haemostatic activation on CB quality.

  10. Des-gamma-carboxy Prothrombin and Alpha fetoprotein as Biomarkers for the Early Detection of Hepatocellular Carcinoma

    PubMed Central

    Lok, Anna S.; Sterling, Richard K.; Everhart, James E.; Wright, Elizabeth C.; Hoefs, John C.; Di Bisceglie, Adrian M.; Morgan, Timothy R.; Kim, Hae-Young; Lee, William M.; Bonkovsky, Herbert L.; Dienstag, Jules L.

    2009-01-01

    Background and Aims: The outcome of patients with hepatocellular carcinoma (HCC) remains poor because of late diagnosis. The aim of this study was to compare the accuracy of alpha fetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) in the early diagnosis of HCC. Methods: Among 1031 patients randomized in the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) Trial, a nested case-control study of 39 HCC cases (24 early stage) and 77 matched controls was conducted to compare the performance of AFP and DCP. Testing was performed on sera from 12 months prior (month −12) to the time of HCC diagnosis (month 0). Results: The sensitivity and specificity of DCP at month 0 was 74% and 86% at a cutoff of 40 mAU/mL and 43% and 100% at a cutoff of 150 mAU/mL. The sensitivity and specificity of AFP at month 0 was 61% and 81% at a cutoff of 20 ng/mL and 22% and 100% at a cutoff of 200 ng/mL. At month −12, the sensitivity and specificity at the low cutoff was 43% and 94% for DCP and 47% and 75% for AFP. Combining both markers increased the sensitivity to 91% at month 0 and 73% at month 12 but the specificity decreased to 74% and 71%. Diagnosis of early HCC was triggered by surveillance ultrasound in 14, doubling of AFP in 5 and combination of tests in 5 patients. Conclusions: Biomarkers are needed to complement ultrasound in the detection of early HCC but neither DCP nor AFP is optimal. PMID:19852963

  11. Replacement of isoleucine-397 by threonine in the clotting proteinase factor IXa (Los Angeles and Long Beach variants) affects macromolecular catalysis but not L-tosylarginine methyl ester hydrolysis. Lack of correlation between the ox brain prothrombin time and the mutation site in the variant proteins.

    PubMed Central

    Spitzer, S G; Warn-Cramer, B J; Kasper, C K; Bajaj, S P

    1990-01-01

    Previously, from the plasma of unrelated haemophilia-B patients, we isolated two non-functional Factor IX variants, namely Los Angeles (IXLA) and Long Beach (IXLB). Both variants could be cleaved to yield Factor IXa-like molecules, but were defective in catalysing the cleavage of Factor X (macromolecular substrate) and in binding to antithrombin III (macromolecular inhibitor). In the present study we have identified the mutation of IXLA by amplifying the exons (including flanking regions) as well as the 5' end of the gene by polymerase-chain-reaction (PCR) method and sequencing the amplified DNA by the dideoxy chain-termination method. Comparison of the normal IX and IXLA sequences revealed only one base substitution (T----C) in exon VIII of IXLA, with a predicted replacement of Ile-397 to Thr in the mature protein. This mutation is the same as found recently for IXLB. The observation that IXLB and IXLA have the same mutation is an unexpected finding, since, on the basis of their ox brain prothrombin time (PT, a test that measures the ability of the variant Factor IX molecules to inhibit the activation of Factor X by Factor VIIa-tissue factor complex), these variants have been classified into two different groups and were thought to be genetically different. Our observation thus suggests that the ox brain PT does not reflect the locus of mutation in the coding region of the variant molecules. However, our analysis suggests that the ox brain PT is related to Factor IX antigen concentration in the patient's plasma. Importantly, although the mutation in IXLA or IXLB protein is in the catalytic domain, purified IXaLA and IXaLB hydrolyse L-tosylarginine methyl ester at rates very similar to that of normal IXa. These data, in conjunction with our recent data on Factor IXBm Lake Elsinore (Ala-390----Val mutant), strengthen a conclusion that the peptide region containing residues 390-397 of normal Factor IXa plays an essential role in macromolecular substrate catalysis and

  12. Replacement of isoleucine-397 by threonine in the clotting proteinase factor IXa (Los Angeles and Long Beach variants) affects macromolecular catalysis but not L-tosylarginine methyl ester hydrolysis. Lack of correlation between the ox brain prothrombin time and the mutation site in the variant proteins.

    PubMed

    Spitzer, S G; Warn-Cramer, B J; Kasper, C K; Bajaj, S P

    1990-01-01

    Previously, from the plasma of unrelated haemophilia-B patients, we isolated two non-functional Factor IX variants, namely Los Angeles (IXLA) and Long Beach (IXLB). Both variants could be cleaved to yield Factor IXa-like molecules, but were defective in catalysing the cleavage of Factor X (macromolecular substrate) and in binding to antithrombin III (macromolecular inhibitor). In the present study we have identified the mutation of IXLA by amplifying the exons (including flanking regions) as well as the 5' end of the gene by polymerase-chain-reaction (PCR) method and sequencing the amplified DNA by the dideoxy chain-termination method. Comparison of the normal IX and IXLA sequences revealed only one base substitution (T----C) in exon VIII of IXLA, with a predicted replacement of Ile-397 to Thr in the mature protein. This mutation is the same as found recently for IXLB. The observation that IXLB and IXLA have the same mutation is an unexpected finding, since, on the basis of their ox brain prothrombin time (PT, a test that measures the ability of the variant Factor IX molecules to inhibit the activation of Factor X by Factor VIIa-tissue factor complex), these variants have been classified into two different groups and were thought to be genetically different. Our observation thus suggests that the ox brain PT does not reflect the locus of mutation in the coding region of the variant molecules. However, our analysis suggests that the ox brain PT is related to Factor IX antigen concentration in the patient's plasma. Importantly, although the mutation in IXLA or IXLB protein is in the catalytic domain, purified IXaLA and IXaLB hydrolyse L-tosylarginine methyl ester at rates very similar to that of normal IXa. These data, in conjunction with our recent data on Factor IXBm Lake Elsinore (Ala-390----Val mutant), strengthen a conclusion that the peptide region containing residues 390-397 of normal Factor IXa plays an essential role in macromolecular substrate catalysis and

  13. Concentrations, profiles, and estimated human exposures for polychlorinated dibenzo-p-dioxins and dibenzofurans from electronic waste recycling facilities and a chemical industrial complex in Eastern China.

    PubMed

    Ma, Jing; Kannan, Kurunthachalam; Cheng, Jinping; Horii, Yuichi; Wu, Qian; Wang, Wenhua

    2008-11-15

    Environmental pollution arising from electronic waste (e-waste) disposal and recycling has received considerable attention in recent years. Treatment, at low temperatures, of e-wastes that contain polyvinylchloride and related polymers can release polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Although several studies have reported trace metals and polybrominated diphenyl ethers (PBDEs) released from e-waste recycling operations, environmental contamination and human exposure to PCDD/Fs from e-waste recycling operations are less well understood. In this study, electronic shredder waste and dust from e-waste facilities, and leaves and surface soil collected in the vicinity of a large scale e-waste recycling facility in Taizhou, Eastern China, were analyzed for total PCDD/ Fs including 2,3,7,8-substituted congeners. We also determined PCDD/Fs in surface agricultural soils from several provinces in China for comparison with soils from e-waste facilities. Concentrations of total PCDD/Fs were high in all of the matrices analyzed and ranged from 30.9 to 11400 pg/g for shredder waste, 3460 to 9820 pg/g dry weight for leaves, 2560 to 148000 pg/g dry weight for workshop-floor dust, and 854 to 10200 pg/g dry weight for soils. We also analyzed surface soils from a chemical industrial complex (a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant) in Shanghai. Concentrations of total PCDD/Fs in surface soil (44.5-531 pg/g dry wt) from the chemical industrial complex were lower than the concentrations found in soils from e-waste recycling plants, but higher than the concentrations found in agricultural soils. Agricultural soils from six cities in China contained low levels (3.44-33.8 pg/g dry wt) of total PCDD/Fs. Profiles of dioxin toxic equivalents (TEQs) of 2,3,7,8-PCDD/Fs in soils from e-waste facilities in Taizhou differed from the profiles found in agricultural soils. The estimated daily intakes of TEQs of PCDD/ Fs via soil/dust ingestion

  14. Effects of proteinate complex zinc on growth performance, hepatic and splenic trace elements concentrations, antioxidative function and immune functions in weaned piglets.

    PubMed

    She, Yue; Huang, Qiang; Li, Defa; Piao, Xiangshu

    2017-08-01

    To assess the effects of proteinate complex zinc (PC-Zn) on growth performance, antioxidative function, trace element concentrations and immune function in weaned piglets. Three hundred newly weaned barrows (Duroc×Landrace×Yorkshire), 28 days of age, were randomly allotted to 3 dietary groups of 5 replicate pens per group for 4 weeks of feeding. Experimental diets were: i) zinc deficient diet (ZnD, 24 mg/kg Zn supplementation from ZnSO4), ii) inorganic Zn diet supplemented with 120 mg/kg of Zn from Zn sulfate (ZnSO4), and iii) organic Zn diet supplemented with 120 mg/kg of Zn from PC-Zn. The body weight of pigs were recorded at the beginning, at the middle and at the end of the experiment, and the amount of feed supplied each day was recorded. Five barrows from each dietary treatment group were selected to be anesthetized and euthanized at the end of the trial to determine the Zn, Cu, Fe, and Mn concentrations, the hepatic metallothionein content, the levels of methane dicarboxylic aldehyde (MDA), Mn, and Cu/Zn superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in the spleen, the levels of interleukin (IL)-2, IL-4, IL-10, interferon (IFN)-γ, CD3(+), CD4(+), and CD8(+) T lymphocyte. The accumulation of Zn in the spleen, levels of SOD, GSH-Px, IL-4, IL-10, the proportions of CD3(+) and CD4(+) T lymphocyte, and the ratio of CD4(+)/CD8(+) T lymphocyte were increased by organic Zn supplementation compared to ZnD, while the levels of MDA, IFN-γ, and proportion of CD8(+) T lymphocyte were lowered. These findings indicate that Zn can improve the antioxidant potential and immune functions of weaned piglets.

  15. Effects of proteinate complex zinc on growth performance, hepatic and splenic trace elements concentrations, antioxidative function and immune functions in weaned piglets

    PubMed Central

    She, Yue; Huang, Qiang; Li, Defa; Piao, Xiangshu

    2017-01-01

    Objective To assess the effects of proteinate complex zinc (PC-Zn) on growth performance, antioxidative function, trace element concentrations and immune function in weaned piglets. Methods Three hundred newly weaned barrows (Duroc×Landrace×Yorkshire), 28 days of age, were randomly allotted to 3 dietary groups of 5 replicate pens per group for 4 weeks of feeding. Experimental diets were: i) zinc deficient diet (ZnD, 24 mg/kg Zn supplementation from ZnSO4), ii) inorganic Zn diet supplemented with 120 mg/kg of Zn from Zn sulfate (ZnSO4), and iii) organic Zn diet supplemented with 120 mg/kg of Zn from PC-Zn. The body weight of pigs were recorded at the beginning, at the middle and at the end of the experiment, and the amount of feed supplied each day was recorded. Five barrows from each dietary treatment group were selected to be anesthetized and euthanized at the end of the trial to determine the Zn, Cu, Fe, and Mn concentrations, the hepatic metallothionein content, the levels of methane dicarboxylic aldehyde (MDA), Mn, and Cu/Zn superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in the spleen, the levels of interleukin (IL)-2, IL-4, IL-10, interferon (IFN)-γ, CD3+, CD4+, and CD8+ T lymphocyte. Results The accumulation of Zn in the spleen, levels of SOD, GSH-Px, IL-4, IL-10, the proportions of CD3+ and CD4+ T lymphocyte, and the ratio of CD4+/CD8+ T lymphocyte were increased by organic Zn supplementation compared to ZnD, while the levels of MDA, IFN-γ, and proportion of CD8+ T lymphocyte were lowered. Conclusion These findings indicate that Zn can improve the antioxidant potential and immune functions of weaned piglets. PMID:28111434

  16. Elimination capacity of a TSE-model agent in the manufacturing process of Alphanate/Fanhdi, a human factor VIII/VWF complex concentrate.

    PubMed

    Diez, J M; Caballero, S; Belda, F J; Otegui, M; Gajardo, R; Jorquera, J I

    2009-11-01

    The variant Creutzfeldt-Jakob disease (vCJD) is a transmissible spongiform encephalopathy (TSE), mainly present in the UK and is associated with the ingestion of bovine products affected with bovine spongiform encephalopathy. Manufacturers of biological products must investigate the ability of their production processes to remove TSE agents. We studied the purification steps in the manufacturing process of two FVIII/VWF concentrates (Alphanate) and Fanhdi in their ability to eliminate an experimental TSE-model agent. Hamster scrapie strain 263K brain-derived materials were spiked into samples of the solutions taken before various stages during its production: 3.5% polyethylene glycol (PEG) precipitation, heparin affinity chromatography and saline precipitation/final filtrations. PEG precipitation and affinity chromatography were studied both as isolated and combined steps. TSE agent removal was determined using a laboratory scale model representative of the industrial manufacturing process. The prion protein (PrP(Sc)) was measured with Western blot and TSE infectivity was measured with bioassay. Western blot results were in agreement with those obtained by bioassay, showing a significant removal capacity in the production process: 3.21-3.43 log(10) for the PEG precipitation; about 3.45 log(10) for the affinity chromatography; and around 2.0 log(10) for the saline precipitation plus final filtrations. PEG precipitation and heparin affinity chromatography were demonstrated to be two complementary TSE-model agent removal mechanisms with total removal being the sum of the two. An overall reduction factor of around 8 log(10) can be deduced. The tests from the production process of FVIII/VWF complex concentrates have demonstrated their potential for eliminating TSE agents.

  17. Effect of injectable trace mineral complex supplementation on development of ovarian structures and serum copper and zinc concentrations in over-conditioned Holstein cows.

    PubMed

    González-Maldonado, Juan; Rangel-Santos, Raymundo; Rodríguez-de Lara, Raymundo; García-Peña, Oswaldo

    2017-03-28

    This study evaluated the effect of injecting trace minerals on reproductive performance in over-conditioned Holstein cows before synchronized estrus. Multiparous non-lactating, over-conditioned repeat breeder cows (n=20) were assigned randomly to one of two treatments: 1) control (n=10), and 2) supplementation with an injectable trace mineral complex 25days before expected synchronized estrus (n=10). Follicular waves were synchronized by intravaginal insertion of a CIDR for eight days and an intramuscular (i.m.) injection of a GnRH analogue. Estrus was induced at CIDR removal by an i.m. injection of PGF2α. Blood samples were collected before and after synchronized estrus. The response variables were follicle population (FP), diameter of the preovulatory follicle at CIDR removal (DFP0) and at estrus detection (DFP1), time of estrus after CIDR removal (TE), area of corpus luteum (ACL), pregnancy rate and copper and zinc serum concentrations. The statistical analysis of the variables was carried out with SAS. The FP, DFP0, DFP1, TE, ACL and serum concentrations of copper and zinc were not affected by the trace mineral injection (P>0.05). Even though pregnancy rate at 40 (77.78±13.46 vs 44.44±16.56%) and 60days after AI (66.67±15.71 vs 33.33±15.71%) was numerically higher for cows injected with trace minerals than for the control group, the differences were not significant (P>0.05). In conclusion, while follicular and corpus luteum development were not affected by trace mineral injection, it may be a feasible way to increase the pregnancy rate in over-conditioned cows.

  18. Does point of care prothrombin time measurement reduce the transfusion of fresh frozen plasma in patients undergoing major surgery? The POC-OP randomized-controlled trial

    PubMed Central

    2009-01-01

    Background Bleeding is a frequent complication during surgery. The intraoperative administration of blood products, including packed red blood cells, platelets and fresh frozen plasma (FFP), is often live saving. Complications of blood transfusions contribute considerably to perioperative costs and blood product resources are limited. Consequently, strategies to optimize the decision to transfuse are needed. Bleeding during surgery is a dynamic process and may result in major blood loss and coagulopathy due to dilution and consumption. The indication for transfusion should be based on reliable coagulation studies. While hemoglobin levels and platelet counts are available within 15 minutes, standard coagulation studies require one hour. Therefore, the decision to administer FFP has to be made in the absence of any data. Point of care testing of prothrombin time ensures that one major parameter of coagulation is available in the operation theatre within minutes. It is fast, easy to perform, inexpensive and may enable physicians to rationally determine the need for FFP. Methods/Design The objective of the POC-OP trial is to determine the effectiveness of point of care prothrombin time testing to reduce the administration of FFP. It is a patient and assessor blind, single center randomized controlled parallel group trial in 220 patients aged between 18 and 90 years undergoing major surgery (any type, except cardiac surgery and liver transplantation) with an estimated blood loss during surgery exceeding 20% of the calculated total blood volume or a requirement of FFP according to the judgment of the physicians in charge. Patients are randomized to usual care plus point of care prothrombin time testing or usual care alone without point of care testing. The primary outcome is the relative risk to receive any FFP perioperatively. The inclusion of 110 patients per group will yield more than 80% power to detect a clinically relevant relative risk of 0.60 to receive FFP of

  19. Prothrombin time and activated partial thromboplastin time using a point-of-care analyser (Abaxis VSpro®) in Bennett's wallabies (Macropus rufogriseus).

    PubMed

    Nevitt, B N; Chinnadurai, S K; Watson, M K; Langan, J N; Adkesson, M J

    2016-10-01

    There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point-of-care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range.

  20. Prothrombin G20210A mutation is associated with young-onset stroke: the genetics of early-onset stroke study and meta-analysis.

    PubMed

    Jiang, Baijia; Ryan, Kathleen A; Hamedani, Ali; Cheng, Yuching; Sparks, Mary J; Koontz, Deborah; Bean, Christopher J; Gallagher, Margaret; Hooper, W Craig; McArdle, Patrick F; O'Connell, Jeffrey R; Stine, O Colin; Wozniak, Marcella A; Stern, Barney J; Mitchell, Braxton D; Kittner, Steven J; Cole, John W

    2014-04-01

    Although the prothrombin G20210A mutation has been implicated as a risk factor for venous thrombosis, its role in arterial ischemic stroke is unclear, particularly among young adults. To address this issue, we examined the association between prothrombin G20210A and ischemic stroke in a white case-control population and additionally performed a meta-analysis. From the population-based Genetics of Early Onset Stroke (GEOS) study, we identified 397 individuals of European ancestry aged 15 to 49 years with first-ever ischemic stroke and 426 matched controls. Logistic regression was used to calculate odds ratios (ORs) in the entire population and for subgroups stratified by sex, age, oral contraceptive use, migraine, and smoking status. A meta-analysis of 17 case-control studies (n=2305 cases <55 years) was also performed with and without GEOS data. Within GEOS, the association of the prothrombin G20210A mutation with ischemic stroke did not achieve statistical significance (OR=2.5; 95% confidence interval [CI]=0.9-6.5; P=0.07). However, among adults aged 15 to 42 years (younger than median age), cases were significantly more likely than controls to have the mutation (OR=5.9; 95% CI=1.2-28.1; P=0.03), whereas adults aged 42 to 49 years were not (OR=1.4; 95% CI=0.4-5.1; P=0.94). In our meta-analysis, the mutation was associated with significantly increased stroke risk in adults ≤55 years (OR=1.4; 95% CI=1.1-1.9; P=0.02), with significance increasing with addition of the GEOS results (OR=1.5; 95% CI=1.1-2.0; P=0.005). The prothrombin G20210A mutation is associated with ischemic stroke in young adults and may have an even stronger association among those with earlier onset strokes. Our finding of a stronger association in the younger young adult population requires replication.

  1. The Prothrombin G20210A Mutation is Associated with Young-Onset Stroke: The Genetics of Early Onset Stroke Study and Meta-Analysis

    PubMed Central

    Jiang, Baijia; Ryan, Kathleen A.; Hamedani, Ali; Cheng, Yuching; Sparks, Mary J.; Koontz, Deborah; Bean, Christopher J.; Gallagher, Margaret; Hooper, W. Craig; McArdle, Patrick F.; O'Connell, Jeffrey R.; Stine, O. Colin; Wozniak, Marcella A.; Stern, Barney J.; Mitchell, Braxton D.; Kittner, Steven J.; Cole, John W.

    2014-01-01

    Background and Purpose Although the prothrombin G20210A mutation has been implicated as a risk factor for venous thrombosis, its role in arterial ischemic stroke is unclear, particularly among young-adults. To address this issue, we examined the association between prothrombin G20210A and ischemic stroke in a Caucasian case-control population and additionally performed a meta-analysis Methods From the population-based Genetics of Early Onset Stroke (GEOS) study we identified 397 individuals of European ancestry aged 15-49 years with first-ever ischemic stroke and 426 matched-controls. Logistic regression was used to calculate odds ratios in the entire population and for subgroups stratified by gender, age, oral contraceptive use, migraine and smoking status. A meta-analysis of 17 case-control studies (n=2305 cases <55 years) was also performed with and without GEOS data. Results Within GEOS, the association of the prothrombin G20210A mutation with ischemic stroke did not achieve statistical significance (OR=2.5,95%CI=0.9-6.5,p=0.07). However, among adults aged 15-42 (younger than median age), cases were significantly more likely than controls to have the mutation (OR=5.9,95%CI=1.2-28.1,p=0.03), whereas adults ages 42-49 were not (OR=1.4,95%CI=0.4-5.1,p=0.94). In our meta-analysis, the mutation was associated with significantly increased stroke risk in adults <=55 years (OR=1.4;95%CI=1.1-1.9;p=0.02) with significance increasing with addition of the GEOS results (OR=1.5;95%CI=1.1-2.0;p=0.005). Conclusions The prothrombin G20210A mutation is associated with ischemic stroke in young-adults and may have an even stronger association among those with earlier onset strokes. Our finding of a stronger association in the younger-young adult population requires replication. PMID:24619398

  2. Interaction of Hurricane Katrina with Optically Complex Water in the Gulf of Mexico: Interpretation Using Satellite-Derived Inherent Optical Properties and Chlorophyll Concentration

    NASA Astrophysics Data System (ADS)

    Lyon, P. E.; Acker, J.; Hoge, F. E.; Shen, S.; Roffer, M.; Gawlikowski, G.

    2008-12-01

    When Hurricane Katrina passed over southern Florida, Florida Bay and the West Florida Shelf, and into the Gulf of Mexico, empirically derived chl a increases were observed in the Tortugas Gyre circulation feature, and in adjacent waters. Analysis of the empirically derived chl a increase within the gyre has been primarily attributed to initiation of a phytoplankton bloom promoted by nutrients upwelled by Katrina's winds. Detailed analysis of inherent optical properties (IOPs) derived from remotely-sensed radiances, however, indicated the interaction of Katrina with shallow coastal and shelf waters likely entrained waters with higher concentrations of chromophoric dissolved organic matter (CDOM) into the gyre circulation, augmenting the chl a signal. Storm-induced upwelling would also transport optically active CDOM to the surface. Increases in empirically derived chl a in the Florida coastal waters influenced by Katrina's winds were therefore partly due to increased absorption by CDOM. This analysis indicates that elevated empirically derived chl a in hurricane-influenced waters should not be unambiguously attributed to increased phytoplankton productivity, particularly in an optically complex coastal environment.

  3. Solution conformations of the gamma-carboxyglutamic acid domain of bovine prothrombin fragment 1, residues 1-65.

    PubMed

    Charifson, P S; Darden, T; Tulinsky, A; Hughey, J L; Hiskey, R G; Pedersen, L G

    1991-01-15

    Molecular dynamics simulations have been performed (AMBER version 3.1) on solvated residues 1-65 of bovine prothrombin fragment 1 (BF1) by using the 2.8-A resolution crystallographic coordinates as the starting conformation for understanding calcium ion-induced conformational changes that precede experimentally observable phospholipid binding. Simulations were performed on the non-metal-bound crystal structure, the form resulting from addition of eight calcium ions to the 1-65 region of the crystal structure, the form resulting from removal of calcium ions after 107 ps and continuing the simulation, and an isolated hexapeptide loop (residues 18-23). In all cases, the 100-ps time scale seemed adequate to sample an ensemble of solution conformers within a particular region of conformation space. The non-metal-containing BF1 did not unfold appreciably during a 106-ps simulation starting from the crystallographic geometry. The calcium ion-containing structure (Ca-BF1) underwent an interesting conformational reorganization during its evolution from the crystal structure: during the time course of a 107-ps simulation, Ca-BF1 experienced a trans----cis isomerization of the gamma-carboxyglutamic acid-21 (Gla-21)-Pro-22 peptide bond. Removal of the calcium ions from this structure followed by 114 ps of additional molecular dynamics showed significant unfolding relative to the final 20-ps average structure of the 107-ps simulation; however, the Gla-21-Pro-22 peptide bond remained cis. A 265-ps simulation on the termini-protected hexapeptide loop (Cys-18 to Cys-23) containing two calcium ions also did not undergo a trans----cis isomerization. It is believed that the necessary activation energy for the transitional event observed in the Ca-BF1 simulation was largely supplied by global conformational events with a possible assist from relief of intermolecular crystal packing forces. The presence of a Gla preceding Pro-22, the inclusion of Pro-22 in a highly strained loop

  4. Self-management of oral anticoagulants with a whole blood prothrombin-time monitor in elderly patients with atrial fibrillation.

    PubMed

    Eldor, Amiram; Schwartz, Joseph

    2002-01-01

    The efficacy of oral anticoagulants (OAC) in reducing the incidence of stroke in elderly patients with atrial fibrillation (AF) has been well documented. The intensity of OAC therapy and deviations in the prothrombin time (PT) are the strongest risk factor for bleeding complications in elderly patients. The aim of this study was to evaluate a more rigorous regulation of OAC by the use of a portable whole blood PT-monitor (CoaguChek) in elderly patients with AF (age 65-80 years). The study group consisted of 20 patients, of whom 17 were evaluable, which were trained to use to CoaguChek monitor and adjust their anticoagulant dose for 12 months. The control group, 20 patients matched for age, gender and the duration of OAC treatment, were tested in an anticoagulant clinic and their OAC dose was adjusted by a physician. To validate the PT-monitor results, the patients performed a total of 129 simultaneous venous blood PT tests at various time points. The correlation coefficient R(2) was 0.707 indicating the accuracy of the CoaguChek results. The self-managed patients perform more frequent measurements 46 +/- 8.9 vs. 15.7 +/- 3.1 PT tests per patient. They demonstrated a within the therapeutic range INR in 80.5% of the tests (95% confidence interval, 76.5-84.1%) as compared to 72.4% (95% confidence interval, 68.5-76.5%) in the control group (p = 0.057). The median value for all CoaguChek International Normalized Ratio (INR) recordings was within therapeutic range in the self-management group as well as in the control group. There were fewer INR results below or above the therapeutic range in the study group. None of the patients had hemorrhagic or thrombotic events during the study. Overall, the study group expressed high satisfaction from using the home monitor. We conclude that home PT monitoring and self-management of OAC are feasible in a motivated population of elderly patients with atrial fibrillation and are probably cost effective.

  5. Prothrombin Time and Activated Partial Thromboplastin Time Testing: A Comparative Effectiveness Study in a Million-Patient Sample

    PubMed Central

    Capoor, Manu N.; Stonemetz, Jerry L.; Baird, John C.; Ahmed, Fahad S.; Awan, Ahsan; Birkenmaier, Christof; Inchiosa, Mario A.; Magid, Steven K.; McGoldrick, Kathryn; Molmenti, Ernesto; Naqvi, Sajjad; Parker, Stephen D.; Pothula, S. M.; Shander, Aryeh; Steen, R. Grant; Urban, Michael K.; Wall, Judith; Fischetti, Vincent A.

    2015-01-01

    Background A substantial fraction of all American healthcare expenditures are potentially wasted, and practices that are not evidence-based could contribute to such waste. We sought to characterize whether Prothrombin Time (PT) and activated Partial Thromboplastin Time (aPTT) tests of preoperative patients are used in a way unsupported by evidence and potentially wasteful. Methods and Findings We evaluated prospectively-collected patient data from 19 major teaching hospitals and 8 hospital-affiliated surgical centers in 7 states (Delaware, Florida, Maryland, Massachusetts, New Jersey, New York, Pennsylvania) and the District of Columbia. A total of 1,053,472 consecutive patients represented every patient admitted for elective surgery from 2009 to 2012 at all 27 settings. A subset of 682,049 patients (64.7%) had one or both tests done and history and physical (H&P) records available for analysis. Unnecessary tests for bleeding risk were defined as: PT tests done on patients with no history of abnormal bleeding, warfarin therapy, vitamin K-dependent clotting factor deficiency, or liver disease; or aPTT tests done on patients with no history of heparin treatment, hemophilia, lupus anticoagulant antibodies, or von Willebrand disease. We assessed the proportion of patients who received PT or aPTT tests who lacked evidence-based reasons for testing. Conclusions This study sought to bring the availability of big data together with applied comparative effectiveness research. Among preoperative patients, 26.2% received PT tests, and 94.3% of tests were unnecessary, given the absence of findings on H&P. Similarly, 23.3% of preoperative patients received aPTT tests, of which 99.9% were unnecessary. Among patients with no H&P findings suggestive of bleeding risk, 6.6% of PT tests and 7.1% of aPTT tests were either a false positive or a true positive (i.e. indicative of a previously-undiagnosed potential bleeding risk). Both PT and aPTT, designed as diagnostic tests, are

  6. Impact of prothrombin time-International Normalized Ratio on outcome of patients with septic shock receiving polymyxin B cartridge hemoperfusion.

    PubMed

    Ishizuka, Mitsuru; Tago, Kazuma; Kubota, Keiichi

    2014-07-01

    Although most patients with septic shock have a poor outcome, some may survive after blood purification treatment such as polymyxin B cartridge hemoperfusion (PMX). To explore the most significant characteristic associated with 28-day mortality in patients with septic shock receiving PMX. Between April 2006 and March 2008, 116 patients with septic shock who had received PMX in a prospectively collected multicenter collaborative study were enrolled. Uni- and multivariate analyses using the Cox proportional hazard model were performed to assess the most significant clinical characteristic that was associated with 28-day mortality. Among 33 clinicolaboratory characteristics, receiver operating characteristic (ROC) curve analyses selected 12 characteristics with recommended cutoff values such as HCO(3)(-) (≤19.8/>19.8; mEq/L), base excess (≤-5.35/>-5.35; mEq/L), diastolic blood pressure (≤48/>48 mmHg), mean arterial pressure (≤73/>73 mmHg), pH (≤7.29/>7.29), interleukin-6 (≤19,150/>19,150 pg/dL), prothrombin time-International Normalized Ratio (PT-INR; ≤2.05/>2.05), predictive value of Acute Physiology and Chronic Health Evaluation II (APACHE II; ≤0.4/>0.4), pyruvate (≤1.82/>1.82 mg/dL), APACHE II score (≤21/>21), acetate/pyruvate ratio (≤19/>19), and acetate (≤44.8/>44.8 mg/dL) on the basis of large area under the ROC curves for 28-day mortality. The results of uni- and multivariate analyses using these selected characteristics revealed that only PT-INR (≤2.05/>2.05; hazard ratio, 2.823; 95% CI, 1.243-6.412; P = .013) was associated with 28-day mortality. Survival curve analysis demonstrated a significant difference in 28-day mortality between patients with lower (≤2.05) and higher (>2.05) PT-INR (P < .001). Prolonged PT-INR is an independent risk factor for 28-day mortality in patients receiving PMX for septic shock. Copyright © 2014 Mosby, Inc. All rights reserved.

  7. A national study of plasma use in critical care: clinical indications, dose and effect on prothrombin time

    PubMed Central

    2011-01-01

    Introduction Fresh frozen plasma (FFP) is widely used, but few studies have described patterns of plasma use in critical care. We carried out a multicentre study of coagulopathy in intensive care units (ICUs) and here describe overall FFP utilisation in adult critical care, the indications for transfusions, factors indicating the doses used and the effects of FFP use on coagulation. Methods We conducted a prospective, multicentre, observational study of all patients sequentially admitted to 29 adult UK general ICUs over 8 weeks. Daily data throughout ICU admission were collected concerning coagulation, relevant clinical outcomes (including bleeding), coagulopathy (defined as international normalised ratio (INR) >1.5, or equivalent prothrombin time (PT)), FFP and cryoprecipitate use and indications for transfusion. Results Of 1,923 admissions, 12.7% received FFP in the ICU during 404 FFP treatment episodes (1,212 FFP units). Overall, 0.63 FFP units/ICU admission were transfused (0.11 units/ICU day). Reasons for FFP transfusion were bleeding (48%), preprocedural prophylaxis (15%) and prophylaxis without planned procedure (36%). Overall, the median FFP dose was 10.8 ml kg-1, but doses varied widely (first to third quartile, 7.2 to 14.4 ml kg-1). Thirty-one percent of FFP treatments were to patients without PT prolongation, and 41% were to patients without recorded bleeding and only mildly deranged INR (<2.5). Higher volumes of FFP were administered when the indication was bleeding (median doses: bleeding 11.1 ml kg-1, preprocedural prophylaxis 9.8 ml kg-1, prophylaxis without procedure 8.9 ml kg-1; P = 0.009 across groups) and when the pretransfusion INR was higher (ranging from median dose 8.9 ml kg-1 at INR ≤1.5 to 15.7 ml kg-1 at INR >3; P < 0.001 across ranges). Regression analyses suggested bleeding was the strongest predictor of higher FFP dose. Pretransfusion INR was more frequently normal when the transfusion indication was bleeding. Overall, posttransfusion

  8. Crystal structure of the prothrombinase complex from the venom of Pseudonaja textilis

    PubMed Central

    Lechtenberg, Bernhard C.; Murray-Rust, Thomas A.; Johnson, Daniel J. D.; Adams, Ty E.; Krishnaswamy, Sriram; Camire, Rodney M.

    2013-01-01

    The prothrombinase complex, composed of the protease factor (f)Xa and cofactor fVa, efficiently converts prothrombin to thrombin by specific sequential cleavage at 2 sites. How the complex assembles and its mechanism of prothrombin processing are of central importance to human health and disease, because insufficient thrombin generation is the root cause of hemophilia, and excessive thrombin production results in thrombosis. Efforts to determine the crystal structure of the prothrombinase complex have been thwarted by the dependence of complex formation on phospholipid membrane association. Pseutarin C is an intrinsically stable prothrombinase complex preassembled in the venom gland of the Australian Eastern Brown Snake (Pseudonaja textilis). Here we report the crystal structures of the fX-fV complex and of activated fXa from P textilis venom and the derived model of active pseutarin C. Structural analysis supports a single substrate binding channel on fVa, to which prothrombin and the intermediate meizothrombin bind in 2 different orientations, providing insight into the architecture and mechanism of the prothrombinase complex—the molecular engine of blood coagulation. PMID:23869089

  9. Lack of association between factor V Leiden and prothrombin G20210A polymorphisms in Tunisian subjects with a history of myocardial infarction.

    PubMed

    Berredjeb Ben Slama, Dhouha; Fekih-Mrissa, Najiba; Haggui, Abdeddayem; Nsiri, Brahim; Baraket, Nadia; Haouala, Habib; Gritli, Nasreddine

    2013-01-01

    Myocardial infarction is a multifactorial disease. It is provoked by occlusions in the coronary arteries resulting from exposure to multiple risk factors. To study the risk of myocardial infarction associated with the gene polymorphisms of factor V Leiden and factor II (G20210A). Cases consisted of 100 myocardial infarction patients who were hospitalized in the Principal Military Hospital of Tunis and 200 control subjects with no history of myocardial infarction. The prevalence of the factor V Leiden was higher in myocardial infarction patients (9%) than in control subjects (6%) with an OR=1.55 (95% CI=0.58-4.12), whereas the prevalence of prothrombin G20210A mutation was 3% and 2.5% in the patient and control groups, respectively [OR=1.21 (95% CI=0.22-5.94)]. Our results indicate that neither factor V Leiden nor the prothrombin G20210A contributed to the risk factors for myocardial infarction. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Association of factor V Leiden, Janus kinase 2, prothrombin, and MTHFR mutations with primary Budd-Chiari syndrome in Egyptian patients.

    PubMed

    El Sebay, Hatem M; Safan, Manal A; Daoud, Ashraf A; Tayel, Safaa I; Nouh, Mohamed A; El Shafie, Shymaa

    2016-01-01

    Budd-Chiari syndrome (BCS) is defined as obstruction of hepatic venous outflow anywhere from the small hepatic veins to the suprahepatic inferior vena cava. The pathogenesis of BCS is still not fully understood. This study aimed to evaluate the association of factor V Leiden (FVL), Janus kinase 2 (JAK2), prothrombin, and methylene tetrahydrofolate reductase (MTHFR) mutations with primary BCS. The study was carried out on 35 patients with primary BCS and 15 age and gender matched healthy individuals as a control group. Genotyping of FVL, prothrombin, and MTHFR mutations was determined by GENEQUALITY AB-THROMBO TYPE kit based on the reverse hybridization principle. JAK2 mutation was determined by polymerase chain reaction-restriction fragment length polymorphism. There was a statistically significant difference between patients and controls regarding FVL, MTHFR C677T, and MTHFR A1298C mutations with odds ratio of 1.83, 2.0, and 1.79, respectively. Hetero MTHFR C677T, hetero FVL, and hetero MTHFR A1298C were the most common etiological factors being responsible for 57.1, 42.9, and 42.9% of primary BCS cases, respectively. It could be concluded that BCS is a multifactorial disease; in the current study, MTHFR C677T mutation was the most common cause of disease. Identification of one cause of BCS should not eliminate investigations for detection of other etiological factors. © 2015 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

  11. Lopap, a prothrombin activator from Lonomia obliqua belonging to the lipocalin family: recombinant production, biochemical characterization and structure–function insights

    PubMed Central

    Reis, Cleyson Valença; Andrade, Sonia Aparecida; Ramos, Oscar Henrique Pereira; Ramos, Celso Raul Romero; Ho, Paulo Lee; Batista, Isabel de Fátima Correia; Chudzinski-Tavassi, Ana Marisa

    2006-01-01

    Using a cDNA library made from Lonomia obliqua caterpillar bristles, we identified a transcript with a 603 bp open reading frame. The deduced protein corresponds to Lopap, a prothrombin activator previously isolated by our group from the bristles of this species. The mature protein is composed by 185 amino acids and shares similarity with members of the lipocalin family. The cDNA encoding the mature form was amplified by PCR, subcloned into pAE vector and used to transform Escherichia coli BL21(DE3) cells. As for the native Lopap, the recombinant fusion protein shows enzymatic activity, promotes prothrombin hydrolysis, generates fragments similar to prethrombin-2 and fragment 1.2 as intermediates, and generates thrombin as the final product. In addition, structural bioinformatics studies indicated several interesting molecular features, including the residues that could be responsible for Lopap's serine protease-like activity and the role of calcium binding in this context. Such catalytic activity has never been found in other members of the lipocalin family. This is the first report describing the recombinant production and biochemical characterization of a Lonomia obliqua lipocalin, as well as the structural features that could be responsible for its serine protease-like catalytic activity. PMID:16734589

  12. Melanin-concentrating hormone receptor 1 polymorphisms are associated with components of energy balance in the Complex Diseases in the Newfoundland Population: Environment and Genetics (CODING) study.

    PubMed

    Fontaine-Bisson, Bénédicte; Thorburn, James; Gregory, Anne; Zhang, Hongwei; Sun, Guang

    2014-02-01

    The melanin-concentrating hormone receptor 1 (MCHR1) is a G protein-coupled receptor that regulates energy balance and body composition in animal models. Inconsistent effects of MCHR1 polymorphisms on energy homeostasis in humans may partly be attributable to environmental factors. We examined the effect of 4 single nucleotide polymorphisms (rs133073, rs133074, rs9611386, and rs882111) in the MCHR1 gene on body composition as well as energy-related lifestyle factors (diet and physical activity). We also examined the effect of gene-lifestyle interactions on body composition. A total of 1153 participants (248 men and 905 women) from the cross-sectional Complex Diseases in the Newfoundland Population: Environment and Genetics (CODING) study were genotyped by using probe-based chemistry validated assays. Diet and physical activity were estimated by using validated frequency questionnaires, and body composition was assessed by using dual-energy X-ray absorptiometry. Three polymorphisms (rs9611386, rs882111, and rs133073) were associated with differences in body-composition measurements (all P < 0.05). There was an interaction between rs9611386 and carbohydrate intake on total mass and waist circumference (both P ≤ 0.01). There was also an interaction between rs9611386 and body mass index categories (normal weight, overweight, and obese) on energy intakes (P = 0.02). A similar interaction was shown with rs882111 (P = 0.02). Interactions were also observed between each of these polymorphisms (rs9611386, rs882111, and rs133073) and physical activity score on body-composition measurements (all P < 0.05). These findings suggest that polymorphisms in the MCHR1 gene are associated with differences in body composition and interact with physiologic and energy-related lifestyle factors.

  13. Large-scale production and properties of a solvent-detergent-treated factor IX concentrate from human plasma.

    PubMed

    Michalski, C; Bal, F; Burnouf, T; Goudemand, M

    1988-01-01

    A human solvent-detergent (SD)-treated factor IX concentrate has been produced from cryoprecipitate-poor plasma using DEAE-Sepharose CL-6B and heparin-Sepharose CL-6B chromatography. The DEAE eluate was incubated with an SD mixture [0.3% tri(n-butyl) phosphate-1% Tween 80, 6-h at 24 degrees C] which was found to inactivate, in less than 1 h, more than 3.8 log10 of vesicular stomatitis virus and more than 4.8 log10 of Sindbis virus; the SD was removed by a subsequent heparin adsorption step. The specific activity of the concentrate was 10.9 +/- 1.3 IU factor IX: c/mg protein (n = 15). The factor IX coagulant to antigen ratio was 0.7 +/- 0.1. The concentrate was essentially free of factors II, VII and X, and protein C. The usual major contaminants of prothrombin complex concentrate (PCC) were absent: the concentrate contained about 94% alpha-1 proteins, and only 4 major proteins were resolved by SDS-PAGE (respective apparent molecular weight: 130, 86, 76 and 69 kilodaltons), and by crossed immunoelectrophoresis against an anti-PCC serum. The nonactivated partial thromboplastin time was equivalent to that of PCC; the product was devoid of factor IXa, of other activated procoagulant factors and of coagulant-active phospholipids (removed with SD in the heparin breakthrough fraction). Animal studies using the Wessler test and acute-toxicity test in rabbits revealed no adverse side effects. SD treatment could thus be used to inactivate viruses in factor IX concentrate and improve the safety of replacement therapy in hemophilia B.

  14. Parvovirus B19 transmission by heat-treated clotting factor concentrates.

    PubMed

    Blümel, Johannes; Schmidt, Ivo; Effenberger, Wolfgang; Seitz, Holger; Willkommen, Hannelore; Brackmann, Hans Herrmann; Löwer, Johannes; Eis-Hübinger, Anna Maria

    2002-11-01

    Human parvovirus B19 (B19) DNA can be frequently detected in plasma-derived coagulation factor concentrates. The production of some clotting factor products includes heat treatment steps for virus inactivation, but the effectiveness of such steps for B19 inactivation is unclear. Moreover, detailed transmission case reports including DNA sequence analysis and quantification of B19 DNA from contaminated heat-treated blood components have not been provided so far. Therefore, the correlation between B19 DNA in blood components and infectivity remains unclear. Asymptomatic B19 infections of two patients with hemophilia A were detected by anti-B19 seroconversion after administration of B19-contaminated heat-treated clotting factors. The suitability of nucleic acid sequence analysis for confirmation of B19 transmission was investigated. Furthermore, the B19 DNA level in blood components was determined and the drug administration was reviewed to calculate the amount of inoculated B19 DNA. Both B19 transmissions from clotting factor products could be confirmed by identical nucleic acid sequences of virus DNA from patients and blood components while sequences from unrelated controls could be differentiated. One patient received, for 4 days, a total of 180 mL vapor heat-treated prothrombin complex concentrate containing 8.6 x 10(6) genome equivalents per mL of B19 DNA. The other patient received 966 mL of low-contamination (4.0 x 10(3) genome equivalents/mL) dry heat-treated FVIII concentrate over a period of 52 days. B19 transmissions can be confirmed by nucleic acid sequencing. However, due to the low variability of the B19 genome, a large part of the B19 genome must be analyzed. The transmissions show that the applied heat treatment procedures were not sufficient to inactivate B19 completely.

  15. Assessment of the 20210 G to A prothrombin variant in a sample of patients from the French Basque Country with various thrombophilic conditions.

    PubMed

    Bauduer, F; Ducout, L; Freyburger, G

    2003-06-01

    We investigated the distribution of the prothrombin variant G20210A (PT20210A) in a sample of 103 patients (mean age: 34.5 years) living in the French Basque Country and presenting with conditions known to be significantly associated with this peculiar mutation according to a literature review. These patients suffered from repeated personal or familial venous thromboses, stroke at young age, or repetitive maternal-fetal disorders (abortions, preeclampsia, fetal growth retardation). Five patients (4.8%) were found to be carriers: two homozygotes and three heterozygotes (one also heterozygote for factor V Leiden). Of note, two presented with mesenteric venous thrombosis. The distribution of PT20210A among our sample was comparable to data from Western European series albeit a tendency for lower mutation prevalence was observed in our subgroup with obstetrical disorders. In addition, no significant difference in PT20210A frequency was evidenced between autochthonous Basques and individuals from other origins.

  16. Structure–activity relationships of the human prothrombin kringle-2 peptide derivative NSA9: anti-proliferative activity and cellular internalization

    PubMed Central

    Hwang, Hyun Sook; Kim, Dong Won; Kim, Soung Soo

    2006-01-01

    The human prothrombin kringle-2 protein inhibits angiogenesis and LLC (Lewis lung carcinoma) growth and metastasis in mice. Additionally, the NSA9 peptide (NSAVQLVEN) derived from human prothrombin kringle-2 has been reported to inhibit the proliferation of BCE (bovine capillary endothelial) cells and CAM (chorioallantoic membrane) angiogenesis. In the present study, we examined the structure–activity relationships of the NSA9 peptide in inhibiting the proliferation of endothelial cells lines e.g. BCE and HUVE (human umbilical vein endothelial). N- or C-terminal truncated derivatives and reverse sequence analogues of NSA9 were prepared and their anti-proliferative activities were assessed using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay. This cell proliferation assay demonstrated that both the N-terminal region and sequence orientation of NSA9 are important for inhibiting the proliferation of endothelial cells. In particular 2 C-terminal truncation derivatives of NSA9 [NSA7 (NSAVQLV) and NSA8 (NSAVQLVE)] inhibited cellular proliferation to a greater extent than did NSA9. The heptapeptide NSA7, was found to be more potent than NSA9 in inhibiting CAM angiogenesis, and tubular formation and migration of HUVE cells. In addition NSA9, NSA8 and NSA7 peptides exhibited considerable inhibitory effects on the proliferation of tumour cells such as B16F10 (murine melanoma), LLC and L929 (murine fibroblast). Also, cellular internalization studies demonstrated that NSA7 was internalized into both endothelial and tumour cells more easily than was NSA9. In conclusion, these results suggest that NSA7, residing within the full sequence of NSA9, contains the required sequence for anti-proliferative activity and cellular internalization. PMID:16390327

  17. The relationship between factor V Leiden, prothrombin G20210A, and MTHFR mutations and the first major thrombotic episode in polycythemia vera and essential thrombocythemia.

    PubMed

    Trifa, Adrian P; Cucuianu, Andrei; Popp, Radu A; Coadă, Camelia A; Costache, Roxana M; Militaru, Mariela S; Vesa, Ştefan C; Pop, Ioan V

    2014-02-01

    Arterial and venous thrombosis are the most frequent complications in patients with polycythemia vera and essential thrombocythemia. We sought to demonstrate a possible contribution of the factor V Leiden, prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) 677 C > T and 1298 A > C mutations to the thrombotic risk in patients with polycythemia vera and essential thrombocythemia along with other biological features of these patients. We included 86 patients with polycythemia vera, of which 34 (39.5 %) had major thrombosis and 95 patients with essential thrombocythemia, of which 22 (23.1 %) had major thrombosis. In the whole cohort of patients, only the factor V Leiden mutation was significantly associated with both arterial and venous thrombosis in univariate and multivariate analysis (odds ratio (OR) = 4.3; 95 % confidence interval (CI) = 1.5-12.5; p = 0.008 and OR = 4.3; 95 % CI = 1.2-15.9; p = 0.02, respectively). Other factors significantly associated with thrombosis in both univariate and multivariate analysis were male sex (OR = 2.8, 95 % CI = 1.4-5.4, p = 0.002 and OR = 3.5, 95 % CI = 1.6-7.6, p = 0.002, respectively) and the JAK2 V617F mutation (OR = 5.5, 95 % CI = 2.1-15, p = 0.0001 and OR = 6.9, 95 % CI = 2.2-21.2, p = 0.001, respectively). In conclusion, among the four mutations analyzed (factor V Leiden, prothrombin G20210A, and MTHFR 677 C > T and 1298 A > C), only factor V Leiden is a major contributor to thrombosis in polycythemia vera and essential thrombocythemia.

  18. Cerebral venous sinus thrombosis as a recurrent thrombotic event in a patient with heterozygous prothrombin G20210A genotype after discontinuation of oral anticoagulation therapy: how long should we treat these patients with warfarin?

    PubMed

    Jukic, Ivana; Titlic, Marina; Tonkic, Ante; Rosenzweig, Daniel

    2007-08-01

    Cerebral venous sinus thrombosis is an uncommon condition with many clinical manifestations, and hereditary prothrombotic conditions such as factor Leiden V, deficiency of protein S, protein C and antithrombin III, as well as prothrombin gene mutation, may account for 10-15% of cases. To date, conflicting results have been reported for recurrent venous thrombosis in the patients with factor V Leiden and prothrombin G20210A mutation, since some studies have shown a higher risk for recurrent venous thrombosis in carriers of these two mutations than in non-carriers, and the last study showed higher risk only for carriers of double defect (homozygous or double heterozygous for this mutations). Case report is presented. We report a case of cerebral sinus thrombosis as a recurrent thrombotic event in a patient with heterozygous prothrombin G20210A genotype after discontinuation of oral anticoagulation therapy. Since many facts are controversial, the use of secondary prophylaxis for thrombosis in these patients is still a matter of debate without clear consensus recommendation. Data on the risk of recurrent thrombotic events in thrombophilic patient is insufficient. The main unclear question concerning these patients is: how long and whom should we treat with long-term anticoagulant therapy as secondary prophylaxis of DVT? The problem for practitioner is that we do not have guidelines and precise recommendations for secondary thromboprophylaxis in this or similar cases. This case is remarkable for its favorable and quick outcome and its rarity, because CSVT is an uncommon condition and heterozygous prothrombin G20210A genotype was only found predisposing factor for CSVT. Further studies of risk of recurrent venous thrombosis in patients with heterozygous prothrombin G20210A genotype with the larger sample size are required.

  19. Coagulation factors bound to procoagulant platelets concentrate in cap structures to promote clotting.

    PubMed

    Podoplelova, Nadezhda A; Sveshnikova, Anastasia N; Kotova, Yana N; Eckly, Anita; Receveur, Nicolas; Nechipurenko, Dmitry Yu; Obydennyi, Sergey I; Kireev, Igor I; Gachet, Christian; Ataullakhanov, Fazly I; Mangin, Pierre H; Panteleev, Mikhail A

    2016-09-29

    Binding of coagulation factors to phosphatidylserine (PS)-exposing procoagulant-activated platelets followed by formation of the membrane-dependent enzyme complexes is critical for blood coagulation. Procoagulant platelets formed upon strong platelet stimulation, usually with thrombin plus collagen, are large "balloons" with a small (∼1 μm radius) "cap"-like convex region that is enriched with adhesive proteins. Spatial distribution of blood coagulation factors on the surface of procoagulant platelets was investigated using confocal microscopy. All of them, including factors IXa (FIXa), FXa/FX, FVa, FVIII, prothrombin, and PS-sensitive marker Annexin V were distributed nonhomogeneously: they were primarily localized in the "cap," where their mean concentration was by at least an order of magnitude, higher than on the "balloon." Assembly of intrinsic tenase on liposomes with various PS densities while keeping the PS content constant demonstrated that such enrichment can accelerate this reaction by 2 orders of magnitude. The mechanisms of such acceleration were investigated using a 3-dimensional computer simulation model of intrinsic tenase based on these data. Transmission electron microscopy and focal ion beam-scanning electron microscopy with Annexin V immunogold-labeling revealed a complex organization of the "caps." In platelet thrombi formed in whole blood on collagen under arterial shear conditions, ubiquitous "caps" with increased Annexin V, FX, and FXa binding were observed, indicating relevance of this mechanism for surface-attached platelets under physiological flow. These results reveal an essential heterogeneity in the surface distribution of major coagulation factors on the surface of procoagulant platelets and suggest its importance in promoting membrane-dependent coagulation reactions.

  20. The concentration-dependent nature of in vitro amphotericin B-itraconazole interaction against Aspergillus fumigatus: isobolographic and response surface analysis of complex pharmacodynamic interactions.

    PubMed

    Meletiadis, Joseph; te Dorsthorst, Debbie T A; Verweij, Paul E

    2006-11-01

    The interaction between polyenes and azoles is not well understood. We therefore explored the in vitro combination of amphotericin B with itraconazole against 14 clinical Aspergillus fumigatus isolates (9 itraconazole susceptible and 5 itraconazole resistant) with a colorimetric broth microdilution checkerboard technique using two drug interaction models able to explore complicated patterns of interactions: the response surface analysis of Bliss independence and the isobolographic analysis of Loewe additivity zero interaction theories. Synergy was found at combinations with low concentrations of amphotericin B (<0.125 mg/L), whereas antagonism was found at combinations with higher concentrations of amphotericin B. For itraconazole-resistant isolates, synergistic interactions were observed at high concentrations of itraconazole (>0.5 mg/L). Synergy was more frequently observed for the itraconazole-resistant isolates than for the itraconazole-susceptible isolates.

  1. Spectrophotometric determination of arsenic by molybdenum blue method in zinc-lead concentrates and related smelter products after chloroform extraction of iodide complex.

    PubMed

    Rao, C S; Rajan, S C; Rao, N V

    1993-05-01

    The most popular and widely applied method for determination of arsenic in ore concentrates is by spectrophotometry of arsenomolybdic acid reduced to molybdenum blue. While applying this method, several authors have developed procedures which varied in the decomposition, separation of arsenic and in the final colour development. Data regarding interference from germanium is inadequate. The present paper describes a procedure, which combines the best features of the previous procedures and is simple, less time consuming and interference-free compared to earlier procedures. This method has been applied to zinc-lead concentrates and related smelter products.

  2. Substitution of egg yolk by a cyclodextrin-cholesterol complex allows a reduction of the glycerol concentration into the freezing medium of equine sperm.

    PubMed

    Blommaert, Didier; Franck, Thierry; Donnay, Isabelle; Lejeune, Jean-Philippe; Detilleux, Johann; Serteyn, Didier

    2016-02-01

    The aim of this work was to completely replace the egg yolk a classical diluent for freezing equine semen by a cyclodextrin-cholesterol complex. At the same time, the reduction in the glycerol content used for cryopreservation and the incubation time between sperm and the freezing media were evaluated. Horse ejaculates were frozen with four different freezing extenders: a frozen reference medium (IF) containing egg yolk and 2.5% glycerol and media without egg yolk but supplemented with 1.5 mg 2-hydroxypropyl-beta-cyclodextrin cholesterol (HPβCD-C) complex and containing either 1% (G1), 2% (G2) or 3% glycerol (G3). Three incubation times (90, 120 and 180 min) at 4 °C between the fresh semen and the different media were tested before freezing. Viability and motility analyses were performed with computer assisted semen analysis (CASA). Results showed that the freezing media containing the HPβCD-C complex with 1%, 2% and 3% glycerol significantly improve the 3 in vitro parameters of post thawing semen quality (viability, progressive and total mobilities) compared to IF. The best improvement of the parameters was obtained with G1 medium and the longest contact time. The substitution of egg yolk by HPβCD-C complex allows the decrease of protein charge of the medium while favouring the cholesterol supply to membrane spermatozoa offering it a better resistance to osmotic imbalance and a better tolerance to the glycerol toxicity. Our results highlight that the egg yolk of an extender for the freezing of horse semen can be completely substituted by HPβCD-C complex.

  3. Assessment of Reproductive Effects of Complex Mixtures of Disinfection By-Products in a Multi-Generational Rat Bioassay of Drinking Water Concentrates - Monterey

    EPA Science Inventory

    To address concerns raised by epidemiology studies, we conducted a multigenerational reproductive toxicity study in rats using a “whole” mixture of drinking water disinfection by-products (DBPs). Raw water was concentrated ~130 fold, chlorinated, and provided as drinking water to...

  4. Assessment of reproductive effects on complex mixtures of disinfection by-products in a multigenerational rat bioassay of drinking water concentrates

    EPA Science Inventory

    To address concerns raised by epidemiology studies, we conducted a multigenerational reproductive toxicity study in rats using a “whole” mixture of drinking water disinfection by-products (DBPs). Raw water was concentrated ~130 fold, chlorinated, and provided as drinking water to...

  5. Alterations of serum zinc, copper, manganese, iron, calcium, and magnesium concentrations and the complexity of interelement relations in patients with obsessive-compulsive disorder.

    PubMed

    Shohag, Hasanuzzaman; Ullah, Ashik; Qusar, Shalahuddin; Rahman, Mustafizur; Hasnat, Abul

    2012-09-01

    The purpose of the present study was to evaluate the status of serum trace elements: zinc, copper, manganese, iron, calcium, and magnesium concentrations in obsessive-compulsive disorder patients. Forty-eight obsessive-compulsive disorder patients and 48 healthy volunteers were included in this study. Patients were recruited from Bangabandhu Sheikh Mujib Medical University by random sampling. Serum trace element concentrations were determined using flame atomic absorption spectroscopy (for zinc, copper, iron, calcium, and magnesium) as well as graphite furnace atomic absorption spectroscopy (for manganese). Data were analyzed using independent t test, Pearson's correlation analysis, regression analysis, and ANOVA. Statistical analysis of these data showed a definite pattern of variation among certain elements in patients with obsessive-compulsive disorder compared to controls. In patients' serum, zinc, iron, and magnesium concentrations decreased significantly (p<0.05) compared to the controls. Serum manganese and calcium concentrations were significantly higher (p<0.05) in patients compared to the controls. These data showed a definite imbalance in the interelement relations in obsessive-compulsive disorder patients compared to controls and therefore suggest a disturbance in the element homeostasis.

  6. Assessment of Reproductive Effects of Complex Mixtures of Disinfection By-Products in a Multi-Generational Rat Bioassay of Drinking Water Concentrates - Monterey

    EPA Science Inventory

    To address concerns raised by epidemiology studies, we conducted a multigenerational reproductive toxicity study in rats using a “whole” mixture of drinking water disinfection by-products (DBPs). Raw water was concentrated ~130 fold, chlorinated, and provided as drinking water to...

  7. Assessment of reproductive effects on complex mixtures of disinfection by-products in a multigenerational rat bioassay of drinking water concentrates

    EPA Science Inventory

    To address concerns raised by epidemiology studies, we conducted a multigenerational reproductive toxicity study in rats using a “whole” mixture of drinking water disinfection by-products (DBPs). Raw water was concentrated ~130 fold, chlorinated, and provided as drinking water to...

  8. Evaluation of concentrations of volatile organic compounds (VOCs) and particulate matter (PM) in an urban area downwind of major petrochemical complexes, in Harris County, Texas

    NASA Astrophysics Data System (ADS)

    Wilkerson, Daryl F.

    Highly Reactive Volatile Organic Compounds (HRVOCs), in particular, the toxic ozone precursors, ethylene, propylene, butenes (1-butene, cis-2-butene, trans-2-butene) and 1, 3 butadiene found in the Houston area are the most critical in the formation of ozone. Exposure to such chemical can cause adverse health effect on the local population of the area, ranging from respiratory distress, asthma, COPD to Cancer. Urban ambient air samples were collected and analyzed from eight monitoring stations (Sites), encompassing the Houston Ship Channel (HSC), in Harris County, Texas. The data was interpreted and analyzed for changes in the concentration of air pollutants, data was collected daily (24 hours) over a time period from September 2013 to August 2014. One 40-minute sample was collected each hour and analyzed by automated gas chromatograph (Auto-GCs) on-site. A total of 70 compounds are measured hourly at each site, in this research the following chemicals were analysis for their average, seasonal and monthly concentrations: ethane, ethylene, propane, propylene, isobutane, n-butane, 1-butene, c-2-butene, t-2-butene and 1,3-butadiene. In this study, seasonal conditions in the area produced ranges from low to high concentrations of these compounds at certain locations. Two Stations had extremely high yearly average concentrations of butane and its isomers (c-2-butene, t-2-butene) and three stations, 1-butene and isobutene concentrations exceeded normal safety limits along with 1,3-butadiene. One station, in particular, close to the HSC had the highest yearly average propylene concentration. Local meteorology also promotes risk issues to the local health of persons within the area/community of interest. This research concluded that the analyzed results of ambient air samples in the urban areas surrounding the Houston Ship Channel (HSC) in Harris County, Texas posed a dual threat. The production of ozone in the daylight hours and depletion of ozone at night, as well as the

  9. Photovoltaic concentrators

    NASA Astrophysics Data System (ADS)

    Boes, E. C.

    1980-01-01

    A status report on photovoltaic (PV) concentrators technology is presented. The major topics covered are as follows: (1) current PV concentrator arrays; designs, performances, and costs; (2) current PV concentrator array components; cells and cell assemblies, optical concentrators, support structures, tracking, and drive; (3) design of PV concentrator arrays; and (4) array manufacturing technology.

  10. Control of geomorphic processes on 10Be concentrations in individual clasts: Complexity of the exposure history in Gobi-Altay range (Mongolia)

    NASA Astrophysics Data System (ADS)

    Vassallo, Riccardo; Ritz, Jean-François; Carretier, Sébastien

    2011-12-01

    The dating of alluvial landforms by cosmogenic nuclides requires distinguishing the pre-deposition inheritance from the post-deposition history of the clasts in the studied marker. Moreover, estimating catchment-scale erosion rates from the concentrations of cosmogenic nuclides in active alluvia requires a good knowledge of the local/regional relationships between rock exhumation and transport through space and time. This is still poorly known for timescales of tens of thousand years. In order to document the evolution of clast exhumation and transport rates through time, we analyze in situ 10Be concentrations in boulders and cobbles from hillslopes to outlet of an arid mountainous catchment located in Gobi-Altay, Mongolia, strongly affected by global climatic changes during the Pleistocene-Holocene period. Samples were collected on bedrock, abandoned alluvial deposits, active colluvia and alluvia. Our results show a large 10Be scattering in the active river bed, consistent with a low and discontinuous catchment erosion rate dominated by mass wasting and fluvial incision. On the contrary, pre-exposure signal within abandoned terraces is much more homogeneous, consistent with climatic pulses responsible of strong erosional events on hillslopes and rapid fluvial transport. These results show that exhumation/transport processes at the catchment scale vary in style and intensity through time as a consequence of climatic oscillations. The occurrence of abrupt climatic changes during short periods of time recorded by 10Be concentrations in abandoned alluvia raise questions about the temporal applicability of catchment erosion rates derived from cosmogenic nuclide concentrations measured in sediments of active rivers. On the other hand, strong and short erosion events limit and homogenize the pre-exposure 10Be signal in associated deposits like debris-flows, making them particularly suitable markers for dating in active tectonic and paleoclimatic studies.

  11. Metal concentrations in the soils and native plants surrounding the old flotation tailings pond of the copper mining and smelting complex Bor (Serbia).

    PubMed

    Antonijević, M M; Dimitrijević, M D; Milić, S M; Nujkić, M M

    2012-03-01

    In this study concentrations of metals in the native plants and soils surrounding the old flotation tailings pond of the copper mine were determined. It has been established that the soil is heavily contaminated with copper, iron and arsenic, the mean concentrations being 1585.6, 29,462.5 and 171.7 mg kg(-1) respectively. All the plants, except manganese, accumulated metallic elements in concentrations which were either in the range of critical and phytotoxic values (Pb and As) or higher (Zn), and even much higher (Cu and Fe) than these values. Otherwise, the accumulation of Mn, Pb and As was considerably lower than that of Cu, Fe and Zn. In most plants the accumulation of target metals was highest in the root. Several plant species showed high bioaccumulation and translocation factor values, which classify them into species for potential use in phytoextraction. The BCF and TF values determined in Prunus persica were 1.20 and 3.95 for Cu, 1.5 and 6.0 for Zn and 1.96 and 5.44 for Pb. In Saponaria officinalis these values were 2.53 and 1.27 for Zn, and in Juglans regia L. they were 8.76 and 17.75 for Zn. The translocation factor in most plants, for most metals, was higher than one, whereas the highest value was determined in Populus nigra for Zn, amounting to 17.8. Among several tolerant species, the most suitable ones for phytostabilization proved to be Robinia pseudoacacia L. for Zn and Verbascum phlomoides L., Saponaria officinalis and Centaurea jacea L. for Mn, Pb and As.

  12. Prevalence of factor V Leiden and prothrombin G20210A mutation in a large French population selected for nonthrombotic history: geographical and age distribution.

    PubMed

    Mazoyer, Elisabeth; Ripoll, Laurent; Gueguen, René; Tiret, Laurence; Collet, Jean-Philippe; dit Sollier, Claire Bal; Roussi, Jacqueline; Drouet, Ludovic

    2009-10-01

    Among inherited risk factors for venous thrombosis, the most common are the FV-G1691A and FII-G20210A polymorphisms. The FV-G1691A polymorphism is preferentially observed in Europe, with differences between European countries. The FII-G20210A polymorphism is observed all over the world. The study was designed to compare the prevalence of the FV-G1691A and FII-G20210A polymorphisms in a large French population of unrelated individuals with no thrombotic disease history and to determine the age and geographical distributions. Over a period of 18 months, 6154 individuals were included throughout France and FV-G1691A and FII-G20210A polymorphisms were determined. The FV-G1691A prevalence was 3.84% (95% confidence interval 3.35-4.33) and the FII-G20210A prevalence was 3.07% (95% CI 2.63-3.51). A north-east/south-west gradient was observed in the FV-G1691A geographical distribution. No difference was observed in the geographical distribution of FII-G20210A polymorphism nor in the age distribution of the two polymorphisms. The prevalence of the two polymorphisms was similar whatever the blood group (O or non-O). Plasma D-dimers were significantly higher in healthy individuals with FV-G1691A but not in individuals with FII-G20210A. Thirty percent of variation in plasma prothrombin level was explained by environmental factors (serum cholesterol, age, oral contraception, hormonal replacement therapy, body mass index, sex) and genetic factors (FII-G20210A). As expected, individuals with FII-G20210A displayed higher plasma prothrombin level compared with individuals with wild type. However, this was not associated with a modification of the fibrin clot elastic modulus. This study shows a differential distribution of the two polymorphisms among the French territory. These polymorphisms confer a very mild hypercoagulable state as shown by the limited increased in basal D-dimers in mutated FV-G1691A populations and only a trend that does not reach statistical significance for FII

  13. Identification of three elicitins and a galactan-based complex polysaccharide from a concentrated culture filtrate of Phytophthora infestans efficient against Pectobacterium atrosepticum.

    PubMed

    Saubeau, Guillaume; Gaillard, Fanny; Legentil, Laurent; Nugier-Chauvin, Caroline; Ferrières, Vincent; Andrivon, Didier; Val, Florence

    2014-09-26

    The induction of plant immunity by Pathogen Associated Molecular Patterns (PAMPs) constitutes a powerful strategy for crop protection. PAMPs indeed induce general defense responses in plants and thus increase plant resistance to pathogens. Phytophthora infestans culture filtrates (CCFs) are known to induce defense responses and decrease the severity of soft rot due to Pectobacterium atrosepticum in potato tubers. The aim of this study was to identify and characterize the active compounds from P. infestans filtrate. The filtrate was fractionated by gel filtration, and the protection effects against P. atrosepticum and the ability to induce PAL activity were tested for each fraction. The fraction active in protection (F1) also induced PAL activity, as did the whole filtrate. Three elicitins (INF1, INF4 and INF5) were identified in F1b, subfraction of F1, by MALDI-TOF-MS and MS/MS analyses. However, deproteinized F1b still showed biological activity against the bacterium, revealing the presence of an additional active compound. GC-MS analyses of the deproteinized fraction highlighted the presence of a galactan-based complex polysaccharide. These experiments demonstrate that the biological activity of the CCF against P. atrosepticum results from a combined action of three elicitins and a complex polysaccharide, probably through the activation of general defense responses.

  14. Procoagulant Adaptation of a Blood Coagulation Prothrombinase-like Enzyme Complex in Australian Elapid Venom

    PubMed Central

    Bos, Mettine H.A.; Camire, Rodney M.

    2010-01-01

    The macromolecular enzyme complex prothrombinase serves an indispensable role in blood coagulation as it catalyzes the conversion of prothrombin to thrombin, a key regulatory enzyme in the formation of a blood clot. Interestingly, a virtually identical enzyme complex is found in the venom of some Australian elapid snakes, which is composed of a cofactor factor Va-component and a serine protease factor Xa-like subunit. This review will provide an overview of the identification and characterization of the venom prothrombinase complex and will discuss the rationale for its powerful procoagulant nature responsible for the potent hemostatic toxicity of the elapid venom. PMID:21127733

  15. Prediction and characterization of the stability enhancing effect of the Cherry-Tag™ in highly concentrated protein solutions by complex rheological measurements and MD simulations.

    PubMed

    Baumann, Pascal; Schermeyer, Marie-Therese; Burghardt, Hannah; Dürr, Cathrin; Gärtner, Jonas; Hubbuch, Jürgen

    2017-08-12

    Solution stability attributes are one of the key parameters within the production and launching phase of new biopharmaceuticals. Instabilities of active biological compounds can reduce the yield of biopharmaceutical productions, and may induce undesired reactions in patients, such as immunogenic rejections. Protein solution stability thus needs to be engineered and monitored throughout production and storage. In contrast to the gold standard of long-term storage experiments applied in industry, novel experimental and in silico molecular dynamics tools for predicting protein solution stability can be applied within several minutes or hours. Here, a rheological approach in combination with molecular dynamics simulations are presented, for determining and predicting long-term phase behavior of highly concentrated protein solutions. A diversity of liquid phase conditions, including salt type, ionic strength, pH and protein concentration are tested in a Glutathione-S-Transferase (GST) case study, in combination with the enzyme with and without solubility-enhancing Cherry-Tag™. The rheological characterization of GST and Cherry-GST solutions enabled a fast and efficient prediction of protein instabilities without the need of long-term protein phase diagrams. Finally, the strong solubility enhancing properties of the Cherry-Tag™ were revealed by investigating protein surface properties in MD simulations. The tag highly altered the overall surface charge and hydrophobicity of GST, making it less accessible to alteration by the chemical surrounding. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Persistence of high lead concentrations and associated effects in Tundra Swans captured near a mining and smelting complex in northern Idaho

    USGS Publications Warehouse

    Blus, L.J.; Henny, C.J.; Hoffman, D.J.; Sileo, L.; Audet, D.J.

    1999-01-01

    Lead poisoning of waterfowl, particularly tundra swans (Cygnus columbianus), has been documented in the Coeur d'Alene River Basin in northern Idaho for nearly a century. Over 90% of the lead-poisoned tundra swans in this area that were necropsied have no ingested lead shot. Spent lead shot from hunting activities over the years is therefore a minor source of lead in these swans. The migrating swans accumulated lethal burdens of lead from ingestion of sediments and aquatic vegetation during a short stopover in the spring. The lead originated from mining and smelting activities. Lead concentrations and physiological characteristics of blood were compared in swans captured in swim-in traps, with moribund swans caught by hand in the lead-contaminated area in 1987 and 1994-1995 and with birds captured by night-lighting in reference areas in 1994-1995. Blood lead concentrations in swans were highest in moribund birds (3.3 ?g g-1 in 1987 and 1995), intermediate in those trapped in the contaminated area (0.82 ?g g-1 in 1987 and 1.8 ?g g-1 in 1995), and lowest (0.11 ?g g-1) in those trapped in the reference areas. daminolevulinic acid dehydratase (ALAD) was significantly inhibited in swans from the contaminated area. Hematocrit and hemoglobin were significantly depressed only in moribund swans. Of the 19 swans found moribund and euthanized, 18 were classified as having lead toxicosis on the basis of lead levels in blood (1.3 to 9.6 ?g g-1) and livers (6 to 40 ?g g-1) and necropsy findings. The 19th swan had aspergillosis. There was no evidence that effects of lead on tundra swans had diminished from 1987 to 1995.

  17. Exploration of the potential energy surfaces, prediction of atmospheric concentrations, and prediction of vibrational spectra for the HO2...(H2O)n (n = 1-2) hydrogen bonded complexes.

    PubMed

    Alongi, Kristin S; Dibble, Theodore S; Shields, George C; Kirschner, Karl N

    2006-03-16

    The hydroperoxy radical (HO2) plays a critical role in Earth's atmospheric chemistry as a component of many important reactions. The self-reaction of hydroperoxy radicals in the gas phase is strongly affected by the presence of water vapor. In this work, we explore the potential energy surfaces of hydroperoxy radicals hydrogen bonded to one or two water molecules, and predict atmospheric concentrations and vibrational spectra of these complexes. We predict that when the HO2 concentration is on the order of 10(8) molecules x cm(-3) at 298 K, that the number of HO2...H2O complexes is on the order of 10(7) molecules x cm(-3) and the number of HO2...(H2O)2 complexes is on the order of 10(6) molecules x cm(-3). Using the computed abundance of HO2...H2O, we predict that, at 298 K, the bimolecular rate constant for HO2...H2O + HO2 is about 10 times that for HO2 + HO2.

  18. Incorporation of dithiooxamide as a complexing agent into cellulose for the removal and pre-concentration of Cu(II) and Cd(II) ions from natural water samples

    NASA Astrophysics Data System (ADS)

    Jorgetto, A. O.; Silva, R. I. V.; Longo, M. M.; Saeki, M. J.; Padilha, P. M.; Martines, M. A. U.; Rocha, B. P.; Castro, G. R.

    2013-01-01

    The present study describes the incorporation of a complexing agent, dithiooxamide, into microcrystalline cellulose for use in the pre-concentration of Cu(II) and Cd(II) ions from aqueous samples. The FTIR spectrum of the adsorbent exhibited an absorption band in the region of 800 cm-1, which confirmed the binding of the silylating agent to the matrix. Elemental analysis indicated the amount of 0.150 mmol g-1 of the complexing agent. The adsorption data were fit to the modified Langmuir equation, and the maximum amount of metal species extracted from the solution, Ns, was determined to be 0.058 and 0.072 mmol g-1 for Cu(II) and Cd(II), respectively. The covering fraction ϕ, which was 0.39 and 0.48 for Cu(II) and Cd(II), respectively, was used to estimate a 1:2 (metal:ligand) ratio in the formed complex, and a binding model was proposed based on this information. The adsorbent was applied in the pre-concentration of natural water samples and exhibited an enrichment factor of approximately 50-fold for the species studied, which enabled its use in the analysis of trace metals in aqueous samples. The system was validated by the analysis of certified standard (1643e), and the adsorbent was stable for more than 20 cycles, thus enabling its safe reutilization.

  19. Exploration of the Potential Energy Surfaces, Prediction of Atmospheric Concentrations, and Prediction of Vibrational Spectra for the HO2···(H2O)n (n=1-2) Hydrogen Bonded Complexes

    PubMed Central

    Alongi, Kristin S.; Dibble, Theodore S.; Shields, George C.; Kirschner, Karl N.

    2008-01-01

    The hydroperoxy radical (HO2) plays a critical role in Earth’s atmospheric chemistry as a component of many important reactions. The self-reaction of hydroperoxy radicals in the gas phase is strongly affected by the presence of water vapor. In this work we explore the potential energy surfaces of hydroperoxy radicals hydrogen bonded to one or two water molecules, and predict atmospheric concentrations and vibrational spectra of these complexes. We predict that when the HO2 concentration is on the order of 108 molecules·cm-3 at 298K, that the number of HO2···H2O complexes is on the order of 107 molecules·cm-3 and the number of HO2···(H2O)2 complexes is on the order of 106 molecules·cm-3. Using the computed abundance of HO2···H2O, we predict that, at 298K, the bimolecular rate constant for HO2···H2O + HO2 is about ten times that for HO2 + HO2. PMID:16526652

  20. Massive pulmonary embolism associated with Factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase gene mutations in a young patient on oral contraceptive pills: a case report.

    PubMed

    Charafeddine, Khalil M; Mahfouz, Rami A; Ibrahim, Georges Y; Taher, Ali T; Hoballah, Jamal J; Taha, Assad M

    2010-10-01

    Factor V Leiden (Factor V G1691A), prothrombin gene mutation G20210A, and homozygous C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene are known to predispose venous thromboembolism (VTE). We present herein a rare case of a young woman heterozygous for these mutations and taking oral contraceptive pills for less than 2 months, diagnosed to have massive deep venous thrombosis and bilateral pulmonary embolism. The patient was managed for 10 days in the hospital and discharged home on oral anticoagulants. This case suggests that screening for these factors in people with family history of thrombosis and in relatives of patients with these mutations is highly recommended to prevent fatal consequences. In addition, a new guideline for treatment and prophylaxis with anticoagulant for these patients and others who are at risk of developing VTE (American College of Chest Physicians [ACCP] guidelines-Chest 2008) has been published recently. Our recommendation is to promote for the internationally published algorithms through their application, where necessary, to prevent any future thrombotic morbidity or mortality incidents.

  1. Synergism between urinary prothrombin fragment 1 and urine: a comparison of inhibitory activities in stone-prone and stone-free population groups.

    PubMed

    Webber, Dawn; Rodgers, Allen L; Sturrock, Edward D

    2002-09-01

    South African blacks rarely form kidney stones compared with whites. This study investigated whether purified urinary prothrombin fragment 1 (UPTF1) derived from blacks is a more potent inhibitor of calcium oxalate crystallisation than that from whites. UPTF1 was purified from the urine of both population groups and their inhibitory activities were compared in a cross-over design in which each protein was tested in ultrafiltered urine from both population groups. Coulter Multisizer, [14C]-oxalate deposition and scanning electron microscopy experiments were used to monitor crystallisation. The study has demonstrated for the first time that UPTF1 promotes nucleation and that inhibitory activity is synergistically dependent upon urine composition. The activity of the whites' UPTF1 was greater than that of the blacks in the whites' urine (e.g. particle size decrease: 31.7% vs. 25.2%), while the blacks' UPTF1 was superior to that of the whites in the blacks' urine (e.g. particle size decrease: 46.5% vs. 32.4%). In addition, when tested in their respective endogenous urines, the blacks' UPTF1 demonstrated superior inhibitory activity on an absolute scale (e.g. particle size decrease: 46.5% vs. 31.7%). Thus, the urine composition of black South Africans may influence their UPTF1 conformation, conferring greater efficacy for inhibition of calcium oxalate crystallisation.

  2. Coagulometer international sensitivity index (ISI) derivation, a rapid method using the prothrombin time/international normalized ratio (PT/INR) Line: a multicenter study.

    PubMed

    Poller, L; Ibrahim, S; Jespersen, J; Pattison, A

    2012-07-01

    The original WHO procedure for prothrombin time (PT) standardization has been almost entirely abandoned because of the universal use of PT coagulometers. These often give different international normalized ratio (INR) results from the manual method, between individual makes of instruments and with instruments from the same manufacture. A simple procedure is required to derive local INR with coagulometers. The PT/INR Line method has recently been developed using five European Concerted Action on Anticoagulation (ECAA) certified plasmas to derive local INR. This procedure has been modified to derive a coagulometer PT/INR Line providing International Sensitivity Index (ISI) and mean normal PT (MNPT) for coagulometers and give local INR. Results have been compared with conventional ISI calibrations at the same laboratories. With human thromboplastins, mean ISI by local calibration was 0.93 (range: 0.77-1.16). With the PT/INR Line, mean coagulometer ISI was higher, for example 0.99 (0.84-1.23) but using the PT/INR Line derived MNPT there was no difference in local INR. Between-centre INR variation of a certified validation plasma was reduced with human and bovine reagents after correction with local ISI calibrations and the PT/INR Line. The PT/INR Line-ISI with its derived MNPT is shown to provide reliable local INR with the 13 different reagent/coagulometer combinations at the 28 centres in this international study. © 2012 International Society on Thrombosis and Haemostasis.

  3. Prothrombin time-international normalized ratio is a useful marker for edoxaban efficacy in preventing venous thromboembolism after total knee arthroplasty.

    PubMed

    Kodato, Kazuki; Ishida, Kazunari; Shibanuma, Nao; Toda, Akihiko; Takayama, Koji; Oka, Shinya; Hayashi, Shinya; Hashimoto, Shingo; Kurosaka, Masahiro; Kuroda, Ryosuke; Matsumoto, Tomoyuki

    2017-08-01

    Deep vein thrombosis (DVT) is one of the main complications following total knee arthroplasty (TKA). In this study, oral administration of 15 mg edoxaban (a factor Xa inhibitor) once daily for 14 days efficiently prevented the incidence of DVT. Our hypothesis was that prothrombin time-international normalized ratio (PT-INR) on the third postoperative day could predict the incidence of DVT following TKA. In this study, 286 subjects were enrolled and divided into two groups according to the presence or absence of DVT. Several variables [age, body mass index, postoperative D-dimer level, PT-INR, and functional recovery findings (standing)] were analysed to determine the predictors of DVT, and for DVT diagnosis, ultrasonography was performed for seven days after surgery. The PT-INR levels were significantly higher in the group that did not develop DVT (p = 0.01). Further analysis with logistic regression analysis and receiver operating characteristic curve was performed. The PT-INR on the third postoperative day was an independent factor of the incidence of DVT (odds ratio 0.210; p = 0.035). The cut-off PT-INR was calculated to be 1.425. PT-INR level is a useful marker in determining whether 15 mg edoxaban administration can prevent DVT after TKA. It is suggested that increment of edoxaban to control PT-INR over the cut-off point might prevent the incidence of DVT.

  4. The comparative influence of prophylactic antibiotics on the prothrombin response to warfarin in the postoperative prosthetic cardiac valve patient. Cefamandole, cefazolin, vancomycin.

    PubMed Central

    Angaran, D M; Dias, V C; Arom, K V; Northrup, W F; Kersten, T G; Lindsay, W G; Nicoloff, D M

    1987-01-01

    A prospective randomized trial was conducted comparing the effect of three antibiotics: cefamandole (CM), cefazolin (CZ), and vancomycin (V), used as prophylaxis for prosthetic valve surgery, on the prothrombin (PT) response to warfarin (W) on the third day of anticoagulant therapy. Twenty patients, with normal preoperative PTs, were randomized to each antibiotic. Their PTs were not significantly different at 2 hours after operation and the morning before W was begun. The three groups received similar W doses for 2 days, and the PT, as percentage of activity, on the morning of the third day demonstrated that V (51 +/- 18%) was significantly greater (p less than 0.005) than CM (29 +/- 14%) or CZ (38 +/- 18%). CM had a significantly greater percentage of change in PT (64 +/- 14%, p less than 0.0001) from the first to third day than either CZ (51.1 +/- 18%) or V (44.6 +/- 19%). CM also had a greater number of patients (6) with PTs greater than or equal to 30 seconds on day 3 than either CZ (1) or V (1). The antibiotic influence on the PT response to W in this study is ranked as CM greater than CZ greater than V. PMID:3300580

  5. The comparative influence of prophylactic antibiotics on the prothrombin response to warfarin in the postoperative prosthetic cardiac valve patient. Cefamandole, cefazolin, vancomycin.

    PubMed

    Angaran, D M; Dias, V C; Arom, K V; Northrup, W F; Kersten, T G; Lindsay, W G; Nicoloff, D M

    1987-08-01

    A prospective randomized trial was conducted comparing the effect of three antibiotics: cefamandole (CM), cefazolin (CZ), and vancomycin (V), used as prophylaxis for prosthetic valve surgery, on the prothrombin (PT) response to warfarin (W) on the third day of anticoagulant therapy. Twenty patients, with normal preoperative PTs, were randomized to each antibiotic. Their PTs were not significantly different at 2 hours after operation and the morning before W was begun. The three groups received similar W doses for 2 days, and the PT, as percentage of activity, on the morning of the third day demonstrated that V (51 +/- 18%) was significantly greater (p less than 0.005) than CM (29 +/- 14%) or CZ (38 +/- 18%). CM had a significantly greater percentage of change in PT (64 +/- 14%, p less than 0.0001) from the first to third day than either CZ (51.1 +/- 18%) or V (44.6 +/- 19%). CM also had a greater number of patients (6) with PTs greater than or equal to 30 seconds on day 3 than either CZ (1) or V (1). The antibiotic influence on the PT response to W in this study is ranked as CM greater than CZ greater than V.

  6. The human prothrombin kringle-2 derived peptide, NSA9, is internalized into bovine capillary endothelial cells through endocytosis and energy-dependent pathways

    SciTech Connect

    Hwang, Hyun Sook; Kim, Soung Soo . E-mail: kimss518@yonsei.ac.kr

    2005-09-23

    Human prothrombin kringle-2 and its partial peptide, NSA9 (NSAVQLVEN), have been reported to have potent anti-angiogenic activities. Here, the internalization mechanism of NSA9 into bovine capillary endothelial (BCE) cells was examined using lactate dehydrogenase (LDH) release assay, fluorescence microscopy, and flow cytometry. LDH release assay results suggested that the integrity of the BCE cell membrane was unaffected by NSA9. Fluorescence microscopy indicated that internalized NSA9 was localized in the cytoplasm around the nucleus, and showed a punctuated fluorescence pattern, which is indicative of endocytic vesicles. Also, the cellular internalization of NSA9 is significantly inhibited by depletion of the cellular ATP pool, endocytosis inhibitors such as chloroquine and nocodazole, and incubation at low temperature (4 deg C). In addition, the anti-proliferative activity of NSA9 against BCE cells was diminished in the presence of endocytosis or metabolic inhibitors. In conclusion, these results strongly suggest that NSA9 might exert its anti-proliferative activity through internalization into BCE cells by endocytosis and energy-dependent pathways.

  7. Maternal factor V Leiden and prothrombin mutations do not seem to contribute to the occurrence of two or more than two consecutive miscarriages in Caucasian patients.

    PubMed

    Baumann, Kristin; Beuter-Winkler, Petra; Hackethal, Andreas; Strowitzki, Thomas; Toth, Bettina; Bohlmann, Michael K

    2013-12-01

    We analysed the prevalence of the most common hereditary thrombophilia (hTP) - factor V Leiden (FVL) mutation, prothrombin 20210 G>A substitution (PT) - and the 677 C>T replacement in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene in Caucasian patients with a history of two and more consecutive recurrent miscarriages (RMs) as compared to healthy controls with an identical ethnic background and at least one live birth. A multicenter analysis of three hTP was performed in 641 RM patients identically screened at specialized university centres. The study groups consisted of 240 patients with 2 (1) and 401 patients with >2 miscarriages (2) and were compared with 157 controls. There was no significant difference in the prevalence of the hTP between RM patients and controls nor within the two study groups. Subgroup analysis showed that the homozygous MTHFR polymorphism was significantly more prevalent in the study group 2 as compared to study group 1 (13.9 versus 7.9%, P = 0.02). In Caucasians, maternal FVL or PT mutations do not seem to contribute to the pathophysiology of RM, irrespective of the number of miscarriages. However, the role of the homozygous MTHFR polymorphism merits further investigation. © 2013 John Wiley & Sons Ltd.

  8. Thrombophilic risk of individuals with rare compound factor V Leiden and prothrombin G20210A polymorphisms: an international case series of 100 individuals.

    PubMed

    Lim, Ming Y; Deal, Allison M; Kim, Steven; Musty, Michael D; Conard, Jacqueline; Simioni, Paolo; Dutrillaux, Fabienne; Eid, Suhair S; Middeldorp, Saskia; Halbmayer, Walter M; Boneu, Bernard; Moia, Marco; Moll, Stephan

    2016-10-01

    The risk of thrombosis in individuals with rare compound thrombophilias, homozygous factor V Leiden (FVL) plus heterozygous prothrombin G20210A (PTM), homozygous PTM plus heterozygous FVL, and homozygous FVL plus homozygous PTM, is unknown. We identified, worldwide, individuals with these compound thrombophilias, predominantly through mailing members of the International Society on Thrombosis and Haemostasis. Physicians were sent a clinical questionnaire. Confirmatory copies of the genetic results were obtained. One hundred individuals were enrolled; 58% were female. Seventy-one individuals had a venous thrombosis (includes superficial and deep vein thrombosis, and pulmonary embolism), 4 had an arterial thrombosis and 6 had both. Nineteen individuals had never had a thrombotic event. Thrombosis-free survival curves demonstrated that 50% of individuals had experienced a thrombotic event by 35 yrs of age, while 50% had a first venous thromboembolic event (VTE; includes all venous thrombosis except superficial thrombosis) by 41 yrs of age; 38.2% of first VTEs were unprovoked. 37% of patients had at least one VTE recurrence. Seventy percent of first pregnancies carried to term and not treated with anticoagulation were thrombosis-free. In conclusion, patients with these rare compound thrombophilias are not exceedingly thrombogenic, even though they have a substantial risk for VTE. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Induction of microglial toll-like receptor 4 by prothrombin kringle-2: a potential pathogenic mechanism in Parkinson’s disease

    PubMed Central

    Shin, Won-Ho; Jeon, Min-Tae; Leem, Eunju; Won, So-Yoon; Jeong, Kyoung Hoon; Park, Sang-Joon; McLean, Catriona; Lee, Sung Joong; Jin, Byung Kwan; Jung, Un Ju; Kim, Sang Ryoung

    2015-01-01

    Microglia-mediated neuroinflammation may play an important role in the initiation and progression of dopaminergic (DA) neurodegeneration in Parkinson’s disease (PD), and toll-like receptor 4 (TLR4) is essential for the activation of microglia in the adult brain. However, it is still unclear whether patients with PD exhibit an increase in TLR4 expression in the brain, and whether there is a correlation between the levels of prothrombin kringle-2 (pKr-2) and microglial TLR4. In the present study, we first observed that the levels of pKr-2 and microglial TLR4 were increased in the substantia nigra (SN) of patients with PD. In rat and mouse brains, intranigral injection of pKr-2, which is not directly toxic to neurons, led to the disruption of nigrostriatal DA projections. Moreover, microglial TLR4 was upregulated in the rat SN and in cultures of the BV-2 microglial cell line after pKr-2 treatment. In TLR4-deficient mice, pKr-2-induced microglial activation was suppressed compared with wild-type mice, resulting in attenuated neurotoxicity. Therefore, our results suggest that pKr-2 may be a pathogenic factor in PD, and that the inhibition of pKr-2-induced microglial TLR4 may be protective against degeneration of the nigrostriatal DA system in vivo. PMID:26440368

  10. Resolution of severe sinus vein thrombosis with super selective thrombolysis in a pre-adolescent with diabetic ketoacidosis and a prothrombin gene mutation.

    PubMed

    Zerah, Michele; Patterson, Robert; Hansen, Inger; Briones, Michael; Dion, Jacques; Renfroe, Ben

    2007-06-01

    Cerebral sinus vein thrombosis is rare in children. So far, only three other cases have been reported in a child with diabetes mellitus. This 10 year-old female presented with classic signs of diabetic ketoacidosis which resolved with standard fluid and insulin therapy. Headache persisted despite biochemical improvement and 6th nerve palsy became evident on Day 3. On Day 5, sudden deterioration in mental status to the point of coma with loss of airway protective reflexes prompted repeat imaging including magnetic resonance venography which demonstrated thrombosis of the superior sagittal, straight, right transverse, right sigmoid and proximal posterior aspect of the left transverse sinuses. Selective thrombolysis using rTPA was performed emergently. Complete lysis of the thrombosed veins was observed within 35 hours. Low molecular weight heparin was continued for 6 months. Significant clinical improvement was noted within 48 hours of the procedure. Six weeks later recovery was complete. Complete hematological work-up for hypercoagulable state revealed a heterozygous mutation of the prothrombin gene (G20210A). Children with this mutation are generally asymptomatic unless challenged by a second risk factor, in this case by severe dehydration and diabetic ketoacidosis. Our patient presented a unique diagnostic challenge at the time of her acute neurological deterioration. Rapid, aggressive intervention with super-selective thrombolysis resulted in complete resolution of severe and potentially life devastating neurological symptoms.

  11. Simulation of mesoscale and diurnal variability of atmospheric CO2 concentrations in a region including complex terrain and densely populated areas

    NASA Astrophysics Data System (ADS)

    Uebel, M.; Bott, A.

    2015-12-01

    For an accurate simulation of the atmospheric state in the planetary boundary layer (PBL) biosphere - atmosphere interactions are of particular importance. Measurements indicate distinct regional scale spatio-temporal patterns in the atmospheric CO2 distribution. The aim of our study is to understand which processes and environmental conditions (e.g. atmospheric transport, land use, orography) generate these patterns and how the variable CO2 concentrations influence the stomatal control of transpiration and photosynthesis. For that, we use the regional scale terrestrial model system TerrSysMP-CO2 that couples the atmospheric model COSMO (developed from the German Meteorological Service) to the Community Land Model (CLM). TerrSysMP-CO2 includes a two-way coupling of CO2, i.e. the actual CO2 mixing ratio is used to calculate the biogenic CO2 fluxes (photosynthesis, autotrophic/heterotrophic respiration) with CLM and, in turn, these fluxes prognostically change the atmospheric CO2 content. High-resolution anthropogenic emissions complete the CO2 budget in TerrSysMP-CO2. We will present final results simulated with TerrSysMP-CO2 over a model domain including a low mountain range and the densely populated Rhine valley in the western part of Germany. Our results show a distinct diurnal cycle of CO2 in the PBL with the highest values occurring in the early morning caused by near surface CO2 accumulation due to soil respiration. With the onset of photosynthesis a strong decrease of atmospheric CO2 is simulated as well as the turbulent vertical transport within the PBL. Downstream of densely populated regions significant higher CO2 concentrations can be seen. Moreover, a strong horizontal heterogeneity arises between narrow valleys and mountain ridges caused by mountain-valley circulations. Compared with model simulations without CO2 dynamics we see changes in the simulated temperature and moisture distribution in the PBL. These can be attributed to the response of

  12. Elliptical concentrators.

    PubMed

    Garcia-Botella, Angel; Fernandez-Balbuena, Antonio Alvarez; Bernabeu, Eusebio

    2006-10-10

    Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used to produce optical devices, including the use of reflective and refractive components or inverse engineering techniques. However, many of these optical components are based on translational symmetries, rotational symmetries, or free-form surfaces. We study a new family of nonimaging concentrators called elliptical concentrators. This new family of concentrators provides new capabilities and can have different configurations, either homofocal or nonhomofocal. Translational and rotational concentrators can be considered as particular cases of elliptical concentrators.

  13. Sorption behavior of the Pt(II) complex anion on manganese dioxide (δ-MnO2): a model reaction to elucidate the mechanism by which Pt is concentrated into a marine ferromanganese crust

    NASA Astrophysics Data System (ADS)

    Maeno, Mamiko Yamashita; Ohashi, Hironori; Yonezu, Kotaro; Miyazaki, Akane; Okaue, Yoshihiro; Watanabe, Koichiro; Ishida, Tamao; Tokunaga, Makoto; Yokoyama, Takushi

    2016-02-01

    It is difficult to directly investigate the chemical state of Pt in marine ferromanganese crusts (a mixture of hydrous iron(III) oxide and manganese dioxide (δ-MnO2)) because it is present at extremely low concentration levels. This paper attempts to elucidate the mechanism by which Pt is concentrated into marine ferromanganese crust from the Earth's continental crust through ocean water. In this investigation, the sorption behavior of the Pt(II) complex ions on the surface of the δ-MnO2 that is a host of Pt was examined as a model reaction. The δ-MnO2 sorbing Pt was characterized by X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) to determine the chemical state of the Pt. Hydrolytic Pt(II) complex ions were specifically sorbed above pH 6 by the formation of a Mn-O-Pt bond. XPS spectra and XANES spectra for δ-MnO2 sorbing Pt showed that the sorbed Pt(II) was oxidized to Pt(IV) on δ-MnO2. The extended X-ray absorption fine structure (EXAFS) analysis showed that the coordination structure of Pt sorbed on δ-MnO2 is almost the same as that of the [Pt(OH)6]2- complex ion used as a standard. Therefore, the mechanism for the concentration of Pt in marine ferromanganese crust may be an oxidative substitution (penetration of Pt(IV) into structure of δ-MnO2) by a reduction-oxidation reaction between Pt(II) in [PtCl4-n(OH)n]2- and Mn(IV) in δ-MnO2 through a Mn-O-Pt bond.

  14. Existence of a squamous cell carcinoma antigen-immunoglobulin complex causes a deviation between squamous cell carcinoma antigen concentrations determined using two different immunoassays: first report of squamous cell carcinoma antigen coupling with immunoglobulin A.

    PubMed

    Mori, Eriko; Kurano, Makoto; Tobita, Akiko; Shimosaka, Hironori; Yatomi, Yutaka

    2017-01-01

    Background Squamous cell carcinoma antigen is used as a tumour marker and is routinely measured in clinical laboratories. We validated two different immunoassays and found three cases in which the squamous cell carcinoma antigen concentrations deviated greatly between the two immunoassays. Here, we aimed to elucidate the mechanisms responsible for these deviations. Methods The squamous cell carcinoma antigen concentrations were determined using the ARCHITECT SCC (CLIA method) and the ST AIA-PACK SCC (FEIA method). We performed polyethylene glycol precipitation and size exclusion chromatography to assess the molecular weight and spike recovery and absorption tests to examine the presence of an autoantibody. Results Both methods exhibited good performances for the measurement of squamous cell carcinoma antigen, although a correlation test showed large differences in the squamous cell carcinoma antigen concentrations measured using the two methods in three cases. The results of polyethylene glycol treatment and size exclusion chromatography indicated the existence of a large molecular weight squamous cell carcinoma antigen in these three cases. The spike recovery tests suggested the possible presence of an autoantibody against squamous cell carcinoma antigen. Moreover, the absorption test revealed that large squamous cell carcinoma antigen complexes were formed by the association of squamous cell carcinoma antigen with IgG in two cases and with both IgG and IgA in one case. Conclusions This study describes the existence of large molecular weight squamous cell carcinoma antigen that has complexed with immunoglobulin in the serum samples. The reason for the deviations between the two immunoassays might be due to differences of their reactivities against the squamous cell carcinoma antigen immune complexes with their autoantibody. To our knowledge, this is the first report to describe the coupling of squamous cell carcinoma antigen with IgA.

  15. Surface complexation modeling for predicting solid phase arsenic concentrations in the sediments of the Mississippi River Valley alluvial aquifer, Arkansas, USA

    USGS Publications Warehouse

    Sharif, M.S.U.; Davis, R.K.; Steele, K.F.; Kim, B.; Hays, P.D.; Kresse, T.M.; Fazio, J.A.

    2011-01-01

    The potential health impact of As in drinking water supply systems in the Mississippi River Valley alluvial aquifer in the state of Arkansas, USA is significant. In this context it is important to understand the occurrence, distribution and mobilization of As in the Mississippi River Valley alluvial aquifer. Application of surface complexation models (SCMs) to predict the sorption behavior of As and hydrous Fe oxides (HFO) in the laboratory has increased in the last decade. However, the application of SCMs to predict the sorption of As in natural sediments has not often been reported, and such applications are greatly constrained by the lack of site-specific model parameters. Attempts have been made to use SCMs considering a component additivity (CA) approach which accounts for relative abundances of pure phases in natural sediments, followed by the addition of SCM parameters individually for each phase. Although few reliable and internally consistent sorption databases related to HFO exist, the use of SCMs using laboratory-derived sorption databases to predict the mobility of As in natural sediments has increased. This study is an attempt to evaluate the ability of the SCMs using the geochemical code PHREEQC to predict solid phase As in the sediments of the Mississippi River Valley alluvial aquifer in Arkansas. The SCM option of the double-layer model (DLM) was simulated using ferrihydrite and goethite as sorbents quantified from chemical extractions, calculated surface-site densities, published surface properties, and published laboratory-derived sorption constants for the sorbents. The model results are satisfactory for shallow wells (10.6. m below ground surface), where the redox condition is relatively oxic or mildly suboxic. However, for the deep alluvial aquifer (21-36.6. m below ground surface) where the redox condition is suboxic to anoxic, the model results are unsatisfactory. ?? 2011 Elsevier Ltd.

  16. Synchronous Volatilization of Sn, Zn, and As, and Preparation of Direct Reduction Iron (DRI) from a Complex Iron Concentrate via CO Reduction

    NASA Astrophysics Data System (ADS)

    Li, Guanghui; You, Zhixiong; Zhang, Yuanbo; Rao, Mingjun; Wen, Peidan; Guo, Yufeng; Jiang, Tao

    2014-09-01

    Sn-, Zn-, and As-bearing iron ores are typical complex ores and are abundantly reserved in China. This kind of ore is difficult to use effectively due to the complicated relationships between iron and the other valuable metal minerals. Excessive Sn, Zn, and As contents would adversely affect ferrous metallurgy operation as well as the quality of the products. In this study, thermodynamic calculations revealed that it was feasible to synchronously volatilize Sn, Zn, and As via CO reduction. Experimental results showed that preoxidation was necessary for the subsequent reductive volatilization of Zn from the pellets, and the proper preoxidation temperature was 700-725°C under air atmosphere. Synchronous volatilization of Sn, Zn, and As was realized by roasting under weak reductive atmosphere after the pellets were preoxidized. The volatilization ratios of 75.88% Sn, 78.88% Zn, and 84.43% As were obtained, respectively, under the conditions by reduction at 1000°C for 100 min with mixed gas of 50% CO + 50% CO2 (in vol.). A metallic pellet (direct reduction iron) with total iron grade of 87.36%, Fe metallization ratio of 89.27%, and residual Sn, Zn, and As contents of 0.071%, 0.009%, and 0.047%, respectively, was prepared. Sn and As were mainly volatilized during weak reductive atmosphere roasting, and those volatilized in the metallization reduction process were negligible. Most of Zn (78.88%) was volatilized during weak reductive atmosphere roasting, while the metallization reduction process only contributed to 16.10% of total Zn volatilization.

  17. Complex correlation between excitatory amino acid-induced increase in the intracellular Ca2+ concentration and subsequent loss of neuronal function in individual neocortical neurons in culture.

    PubMed Central

    Witt, M R; Dekermendjian, K; Frandsen, A; Schousboe, A; Nielsen, M

    1994-01-01

    Primary cultures of cerebral cortical neurons and single-cell imaging of intracellular free Ca2+ concentration ([Ca2+]i) with the ratiometric dye fura-2 were used to assess excitatory amino acid (EAA)-induced neurotoxicity; the loss of neuronal function as defined by the ability of the cells to respond to K(+)-induced depolarization by a transient increase in Ca2+ influx was measured. The responsiveness of individual neurons was measured quantitatively as the [Ca2+]i values of the second KCl (2.KCl) stimulation divided by those of the first KCl (1.KCl) stimulation, giving the value of the ratio (2.KCl/1.KCl). Exposure to EAAs led to an increase in [Ca2+]i, but no simple correlation between the increase in [Ca2+]i and neuronal responsiveness could be demonstrated. Rather, below a threshold level of [Ca2+]i (ca. 1 microM), the neuronal responsiveness was largely independent of the glutamate receptor-agonist-induced increase in [Ca2+]i. However, when [Ca2+]i increased above this threshold level, the neurons almost invariably lost the ability to respond to a K(+)-induced depolarization, particularly after exposure to glutamate. Therefore, the cortical neurons were found to be exceptionally vulnerable to the glutamate-induced loss of function when compared with the effect induced by the glutamate receptor subtype-specific agonists, N-methyl-D-aspartate, quisqualate, and 2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl) propionate. The findings suggest that the loss of neuronal membrane polarization precedes plasma membrane disruption and is a sensitive marker of EAA-induced neurodegeneration observed at the single-cell level. Images PMID:7527559

  18. Phosphatidylserine-dependent anti-prothrombin antibodies (aPS/PT) in infliximab-treated patients with inflammatory bowel diseases.

    PubMed

    Malíčková, Karin; Ďuricová, Dana; Bortlík, Martin; Janatková, Ivana; Zima, Tomáš; Lukáš, Milan

    2013-04-01

    To (1) examine the occurrence and concentrations of aPS/PT and aPL in inflammatory bowel disease (IBD) patients at the beginning of and during anti-TNF-alpha therapy with infliximab; (2) investigate the link of the aPS/PT and aPL presence with antibodies to infliximab (ATI) formation; and (3) examine possible clinical consequences of aPS/PT and/or aPL positivity in IBD patients. Thirty (30) IBD patients treated with infliximab were analyzed regarding aPS/PT, aPL, and ATI antibody serum levels by standardized ELISAs at treatment weeks 2 (W2) and 14 (W14). At W2, 40 % of infliximab-treated patients had elevated aPS/PT and 16.7 % had elevated aPL serum levels. At W14, the proportion of aPS/PT-positive sera decreased to 16.6 %, whereas aPL distribution remained unchanged. Moreover, concentrations of aPS/PT have shown significant differences at W2 (16.64 [10.06; 33.06] U for IgG and 18.46 [9.18; 32.48] U for IgM) and at W14 (8.24 [2.78; 19.82] U for IgG and 8.57 [5.55; 26.82] U for IgM), p = 0.009 and p = 0.003, respectively. In ATI-positive samples, aPS/PT IgG were more frequent (p = 0.001 for W2 and p = 0.003 for W14), whereas aPS/PT IgM and aPL IgG/IgM did not show such association. Higher concentrations of aPS/PT IgG and IgM were found in IBD patients at the beginning of the biological treatment period compared to the maintenance treatment period. Moreover, aPS/PT IgG were more frequent in ATI-positive individuals, which was not observed in aPL. We speculate that there is a relationship between the aPS/PT and the severity of inflammation and auto-aggressive processes in IBD.

  19. Effects of recombinant human prothrombin on thrombin generation in plasma from patients with hemophilia A and B.

    PubMed

    Hansson, K M; Gustafsson, D; Skärby, T; Frison, L; Berntorp, E

    2015-07-01

    The present study was carried out to investigate the impact of FII levels, and their increase, on the hemostatic potential in plasma from hemophilia A and B patients with and without inhibitors. Recombinant human factor (F) II (rhFII) was added ex vivo to plasma from 68 patients with hemophilia A and B, with or without inhibitors. The hemostatic potential as measured by thrombin generation (calibrated automated thrombogram [CAT]) was focused on the endogenous thrombin potential (ETP) as it has been shown to correlate with the clinical phenotype of bleeding in hemophilia patients and has also been used to guide bypassing therapy in hemophilia patients with inhibitors before elective surgery. The factor eight inhibitor bypassing agent (FEIBA(®) ) was used as a reference to the clinical situation. The study shows that rhFII concentration-dependently increased ETP by a similar magnitude in hemophilia A and B, both with and without inhibitors. Compared with FEIBA, rhFII showed a shallower concentration-response curve. In both types of hemophilia 100 mg L(-1) of rhFII roughly doubled the ETP. A corresponding response was obtained by 0.5 U mL(-1) of FEIBA. These data support the theory that FII is one of the major components responsible for the efficacy of FEIBA. The data also indicate that rhFII may be useful, alone or in combination with other coagulation factors, in some of the conditions for which FEIBA is used today, although more data are needed to substantiate this. © 2015 International Society on Thrombosis and Haemostasis.

  20. Charge carrier effective mass and concentration derived from combination of Seebeck coefficient and Te125 NMR measurements in complex tellurides

    SciTech Connect

    Levin, E. M.

    2016-06-27

    Thermoelectric materials utilize the Seebeck effect to convert heat to electrical energy. The Seebeck coefficient (thermopower), S, depends on the free (mobile) carrier concentration, n, and effective mass, m*, as S ~ m*/n2/3. The carrier concentration in tellurides can be derived from 125Te nuclear magnetic resonance (NMR) spin-lattice relaxation measurements. The NMR spin-lattice relaxation rate, 1/T1, depends on both n and m* as 1/T1~(m*)3/2n (within classical Maxwell-Boltzmann statistics) or as 1/T1~(m*)2n2/3 (within quantum Fermi-Dirac statistics), which challenges the correct determination of the carrier concentration in some materials by NMR. Here it is shown that the combination of the Seebeck coefficient and 125Te NMR spin-lattice relaxation measurements in complex tellurides provides a unique opportunity to derive the carrier effective mass and then to calculate the carrier concentration. This approach was used to study AgxSbxGe50–2xTe50, well-known GeTe-based high-efficiency tellurium-antimony-germanium-silver thermoelectric materials, where the replacement of Ge by [Ag+Sb] results in significant enhancement of the Seebeck coefficient. Thus, values of both m* and n derived using this combination show that the enhancement of thermopower can be attributed primarily to an increase of the carrier effective mass and partially to a decrease of the carrier concentration when the [Ag+Sb] content increases.

  1. Charge carrier effective mass and concentration derived from combination of Seebeck coefficient and Te125 NMR measurements in complex tellurides

    SciTech Connect

    Levin, E. M.

    2016-06-27

    Thermoelectric materials utilize the Seebeck effect to convert heat to electrical energy. The Seebeck coefficient (thermopower), S, depends on the free (mobile) carrier concentration, n, and effective mass, m*, as S ~ m*/n2/3. The carrier concentration in tellurides can be derived from 125Te nuclear magnetic resonance (NMR) spin-lattice relaxation measurements. The NMR spin-lattice relaxation rate, 1/T1, depends on both n and m* as 1/T1~(m*)3/2n (within classical Maxwell-Boltzmann statistics) or as 1/T1~(m*)2n2/3 (within quantum Fermi-Dirac statistics), which challenges the correct determination of the carrier concentration in some materials by NMR. Here it is shown that the combination of the Seebeck coefficient and 125Te NMR spin-lattice relaxation measurements in complex tellurides provides a unique opportunity to derive the carrier effective mass and then to calculate the carrier concentration. This approach was used to study AgxSbxGe50–2xTe50, well-known GeTe-based high-efficiency tellurium-antimony-germanium-silver thermoelectric materials, where the replacement of Ge by [Ag+Sb] results in significant enhancement of the Seebeck coefficient. Thus, values of both m* and n derived using this combination show that the enhancement of thermopower can be attributed primarily to an increase of the carrier effective mass and partially to a decrease of the carrier concentration when the [Ag+Sb] content increases.

  2. Thermodynamic modeling of poorly complexing metals in concentrated electrolyte solutions: an X-ray absorption and UV-Vis spectroscopic study of Ni(II) in the NiCl2-MgCl2-H2O system.

    PubMed

    Zhang, Ning; Brugger, Joël; Etschmann, Barbara; Ngothai, Yung; Zeng, Dewen

    2015-01-01

    Knowledge of the structure and speciation of aqueous Ni(II)-chloride complexes is important for understanding Ni behavior in hydrometallurgical extraction. The effect of concentration on the first-shell structure of Ni(II) in aqueous NiCl2 and NiCl2-MgCl2 solutions was investigated by Ni K edge X-ray absorption (XAS) and UV-Vis spectroscopy at ambient conditions. Both techniques show that no large structural change (e.g., transition from octahedral to tetrahedral-like configuration) occurs. Both methods confirm that the Ni(II) aqua ion (with six coordinated water molecules at RNi-O = 2.07(2) Å) is the dominant species over the whole NiCl2 concentration range. However, XANES, EXAFS and UV-Vis data show subtle changes at high salinity (> 2 mol∙kg(-1) NiCl2), which are consistent with the formation of small amounts of the NiCl+ complex (up to 0.44(23) Cl at a Ni-Cl distance of 2.35(2) Å in 5.05 mol∙kg(-1) NiCl2) in the pure NiCl2 solutions. At high Cl:Ni ratio in the NiCl2-MgCl2-H2O solutions, small amounts of [NiCl2]0 are also present. We developed a speciation-based mixed-solvent electrolyte (MSE) model to describe activity-composition relationships in NiCl2-MgCl2-H2O solutions, and at the same time predict Ni(II) speciation that is consistent with our XAS and UV-Vis data and with existing literature data up to the solubility limit, resolving a long-standing uncertainty about the role of chloride complexing in this system.

  3. Thermodynamic Modeling of Poorly Complexing Metals in Concentrated Electrolyte Solutions: An X-Ray Absorption and UV-Vis Spectroscopic Study of Ni(II) in the NiCl2-MgCl2-H2O System

    PubMed Central

    Zhang, Ning; Brugger, Joël; Etschmann, Barbara; Ngothai, Yung; Zeng, Dewen

    2015-01-01

    Knowledge of the structure and speciation of aqueous Ni(II)-chloride complexes is important for understanding Ni behavior in hydrometallurgical extraction. The effect of concentration on the first-shell structure of Ni(II) in aqueous NiCl2 and NiCl2-MgCl2 solutions was investigated by Ni K edge X-ray absorption (XAS) and UV-Vis spectroscopy at ambient conditions. Both techniques show that no large structural change (e.g., transition from octahedral to tetrahedral-like configuration) occurs. Both methods confirm that the Ni(II) aqua ion (with six coordinated water molecules at RNi-O = 2.07(2) Å) is the dominant species over the whole NiCl2 concentration range. However, XANES, EXAFS and UV-Vis data show subtle changes at high salinity (> 2 mol∙kg-1 NiCl2), which are consistent with the formation of small amounts of the NiCl+ complex (up to 0.44(23) Cl at a Ni-Cl distance of 2.35(2) Å in 5.05 mol∙kg-1 NiCl2) in the pure NiCl2 solutions. At high Cl:Ni ratio in the NiCl2-MgCl2-H2O solutions, small amounts of [NiCl2]0 are also present. We developed a speciation-based mixed-solvent electrolyte (MSE) model to describe activity-composition relationships in NiCl2-MgCl2-H2O solutions, and at the same time predict Ni(II) speciation that is consistent with our XAS and UV-Vis data and with existing literature data up to the solubility limit, resolving a long-standing uncertainty about the role of chloride complexing in this system. PMID:25885410

  4. The prevalence of methylenetetrahydrofolate reductase 677 C-T, factor V 1691 G-A, and prothrombin 20210 G-A mutations in healthy populations in Setif, Algeria.

    PubMed

    Bourouba, Romyla; Houcher, Bakhouche; Djabi, Farida; Egin, Yonca; Akar, Nejat

    2009-10-01

    The polymorphic mutation 677 C-T in the methylenetetrahydrofolate reductase (MTHFR) gene presents a heterogeneous worldwide distribution and is associated with different disorders such as cardiovascular disease. Its frequency shows great ethnic and geographic variations. The aim of this work is to determine the frequency of MTHFR 677 C-T and coexistence of MTHFR 677 C-T with 2 other common, hereditary thrombophilia causes-namely, factor V 1691 G-A and prothrombin (PT) 20210 G-A mutation-in the Sétif region of Algeria. The study involved 147 apparently healthy participants (82 men and 65 women). Genotyping was carried out by a real-time polymerase chain reaction. The MTHFR 677T carrier frequency was found to be 54.4% (80/147); 59 individuals were heterozygous (40.1%), and 21 were homozygous (14.3%). The frequency of MTHFR 677T was found to be 34.3%. Among the 147 individuals, 3 (2.0%) had factor V Leiden, and 5 (3.4%) had PT 20210 A mutation. Of the 80 participants with MTHFR 677T mutation, 2 had heterozygote factor V 1691 G-A gene mutation, and 4 had heterozygote PT 20210 G-A gene mutation. The results showed that MTHFR 677T prevalence is quite high: an allelic frequency of 34.3% with a genotype frequency of 14.3%. Factor V 1691 G-A and PT 20210 G-A gene mutations are rare in the healthy population of the Sétif region of Algeria.

  5. An evaluation of patient self-testing competency of prothrombin time for managing anticoagulation: pre-randomization results of VA Cooperative Study #481--The Home INR Study (THINRS).

    PubMed

    Dolor, Rowena J; Ruybalid, R Lynne; Uyeda, Lauren; Edson, Robert G; Phibbs, Ciaran; Vertrees, Julia E; Shih, Mei-Chiung; Jacobson, Alan K; Matchar, David B

    2010-10-01

    Prior studies suggest patient self-testing (PST) of prothrombin time (PT) can improve the quality of anticoagulation (AC) and reduce complications (e.g., bleeding and thromboembolic events). "The Home INR Study" (THINRS) compared AC management with frequent PST using a home monitoring device to high-quality AC management (HQACM) with clinic-based monitoring on major health outcomes. A key clinical and policy question is whether and which patients can successfully use such devices. We report the results of Part 1 of THINRS in which patients and caregivers were evaluated for their ability to perform PST. Study-eligible patients (n = 3643) were trained to use the home monitoring device and evaluated after 2-4 weeks for PST competency. Information about demographics, medical history, warfarin use, medications, plus measures of numeracy, literacy, cognition, dexterity, and satisfaction with AC were collected. Approximately 80% (2931 of 3643) of patients trained on PST demonstrated competency; of these, 8% (238) required caregiver assistance. Testers who were not competent to perform PST had higher numbers of practice attempts, higher cuvette wastage, and were less able to perform a fingerstick or obtain blood for the cuvette in a timely fashion. Factors associated with failure to pass PST training included increased age, previous stroke history, poor cognition, and poor manual dexterity. A majority of patients were able to perform PST. Successful home monitoring of PT with a PST device required adequate levels of cognition and manual dexterity. Training a caregiver modestly increased the proportion of patients who can perform PST.

  6. The prothrombin time/international normalized ratio (PT/INR) Line: derivation of local INR with commercial thromboplastins and coagulometers--two independent studies.

    PubMed

    Poller, L; Ibrahim, S; Keown, M; Pattison, A; Jespersen, J

    2011-01-01

    The WHO scheme for prothrombin time (PT) standardization has been limited in application, because of its difficulties in implementation, particularly the need for mandatory manual PT testing and for local provision of thromboplastin international reference preparations (IRP). The value of a new simpler procedure to derive international normalized ratio (INR), the PT/INR Line, based on only five European Concerted Action on Anticoagulation (ECAA) calibrant plasmas certified by experienced centres has been assessed in two independent exercises using a range of commercial thromboplastins and coagulometers. INRs were compared with manual certified values with thromboplastin IRP from expert centres and in the second study also with INRs from local ISI calibrations. In the first study with the PT/INR Line, 8.7% deviation from certified INRs was reduced to 1.1% with human reagents, and from 7.0% to 2.6% with rabbit reagents. In the second study, deviation was reduced from 11.2% to 0.4% with human reagents by both local ISI calibration and the PT/INR Line. With rabbit reagents, 10.4% deviation was reduced to 1.1% with both procedures; 4.9% deviation was reduced to 0.5% with bovine/combined reagents with local ISI calibrations and to 2.9% with the PT/INR Line. Mean INR dispersion was reduced with all thromboplastins and automated systems using the PT/INR Line. The procedure using the PT/INR Line provides reliable INR derivation without the need for WHO ISI calibration across the range of locally used commercial thromboplastins and automated PT systems included in two independent international studies. © 2010 International Society on Thrombosis and Haemostasis.

  7. Influence of 8 and 24-h storage of whole blood at ambient temperature on prothrombin time, activated partial thromboplastin time, fibrinogen, thrombin time, antithrombin and D-dimer.

    PubMed

    Kemkes-Matthes, Bettina; Fischer, Ronald; Peetz, Dirk

    2011-04-01

    This study evaluates the effect of whole blood storage on common coagulation parameters in order to confirm or revise acceptable storage limits as defined by current guidelines and diverse study reports. Aliquots were taken from the citrated whole blood of inpatients and outpatients (n = 147) within 4 h after blood withdrawal and after extended storage of whole blood for 8 and 24 h at ambient temperature. Aliquots were centrifuged and analyzed for prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (Fbg), antithrombin (AT), thrombin time (TT) and D-dimer. For each parameter, samples from 33-56 patients were investigated covering a wide range of normal and pathological values. Samples from patients receiving heparin were excluded from analyses of APTT and TT. All assays were performed using reagents and an analyzer from Siemens Healthcare Diagnostics Products GmbH. The mean percentage change after 8 and 24-h storage was below 10% for all parameters. Considering the changes in individual samples, all parameters can be reliably tested after 8-h storage, since less than 15% of the samples demonstrated individual changes of above 10%. The acceptable storage time can be extended to 24 h for PT, TT and D-dimer. Clinically relevant changes were detected after 24-h storage for APTT: 41% of the investigated samples demonstrated changes of above 10%. After 24-h storage, changes for Fbg and AT values were more than 15% in five out of 49 and in three out of 45 samples, respectively. This sporadic increase of values is clinically acceptable except for borderline samples.