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Sample records for anticoagulant activated protein

  1. Relationship between protein C antigen and anticoagulant activity during oral anticoagulation and in selected disease states.

    OpenAIRE

    Vigano D'Angelo, S; Comp, P C; Esmon, C T; D'Angelo, A.

    1986-01-01

    Protein C is a natural vitamin K-dependent plasma anticoagulant, deficiencies of which have been found in patients with recurrent thrombosis and warfarin-induced skin necrosis. To appreciate more fully the role of protein C in disease states and during oral anticoagulation, a new functional assay for protein C involving adsorption of plasma protein C on a Ca+2-dependent monoclonal antibody, elution, quantitative activation, and assessment of plasma anticoagulant activity, has been developed. ...

  2. Platelet factor 4 impairs the anticoagulant activity of activated protein C.

    LENUS (Irish Health Repository)

    Preston, Roger J S

    2012-02-01

    Platelet factor 4 (PF4) is an abundant platelet alpha-granule chemokine released following platelet activation. PF4 interacts with thrombomodulin and the gamma-carboxyglutamic acid (Gla) domain of protein C, thereby enhancing activated protein C (APC) generation by the thrombin-thrombomodulin complex. However, the protein C Gla domain not only mediates protein C activation in vivo, but also plays a critical role in modulating the diverse functional properties of APC once generated. In this study we demonstrate that PF4 significantly inhibits APC anti-coagulant activity. PF4 inhibited both protein S-dependent APC anticoagulant function in plasma and protein S-dependent factor Va (FVa) proteolysis 3- to 5-fold, demonstrating that PF4 impairs protein S cofactor enhancement of APC anticoagulant function. Using recombinant factor Va variants FVa-R506Q\\/R679Q and FVa-R306Q\\/R679Q, PF4 was shown to impair APC proteolysis of FVa at position Arg(306) by 3-fold both in the presence and absence of protein S. These data suggest that PF4 contributes to the poorly understood APC resistance phenotype associated with activated platelets. Finally, despite PF4 binding to the APC Gla domain, we show that APC in the presence of PF4 retains its ability to initiate PAR-1-mediated cytoprotective signaling. In summary, we propose that PF4 acts as a critical regulator of APC generation, but also differentially targets APC toward cytoprotective, rather than anticoagulant function at sites of vascular injury with concurrent platelet activation.

  3. Platelet factor 4 impairs the anticoagulant activity of activated protein C.

    LENUS (Irish Health Repository)

    Preston, Roger J S

    2009-02-27

    Platelet factor 4 (PF4) is an abundant platelet alpha-granule chemokine released following platelet activation. PF4 interacts with thrombomodulin and the gamma-carboxyglutamic acid (Gla) domain of protein C, thereby enhancing activated protein C (APC) generation by the thrombin-thrombomodulin complex. However, the protein C Gla domain not only mediates protein C activation in vivo, but also plays a critical role in modulating the diverse functional properties of APC once generated. In this study we demonstrate that PF4 significantly inhibits APC anti-coagulant activity. PF4 inhibited both protein S-dependent APC anticoagulant function in plasma and protein S-dependent factor Va (FVa) proteolysis 3- to 5-fold, demonstrating that PF4 impairs protein S cofactor enhancement of APC anticoagulant function. Using recombinant factor Va variants FVa-R506Q\\/R679Q and FVa-R306Q\\/R679Q, PF4 was shown to impair APC proteolysis of FVa at position Arg(306) by 3-fold both in the presence and absence of protein S. These data suggest that PF4 contributes to the poorly understood APC resistance phenotype associated with activated platelets. Finally, despite PF4 binding to the APC Gla domain, we show that APC in the presence of PF4 retains its ability to initiate PAR-1-mediated cytoprotective signaling. In summary, we propose that PF4 acts as a critical regulator of APC generation, but also differentially targets APC toward cytoprotective, rather than anticoagulant function at sites of vascular injury with concurrent platelet activation.

  4. The protein C omega-loop substitution Asn2Ile is associated with reduced protein C anticoagulant activity.

    LENUS (Irish Health Repository)

    Preston, Roger J S

    2012-02-01

    We report a kindred with heritable protein C (PC) deficiency in which two siblings with severe thrombosis showed a composite type I and IIb PC deficiency phenotype, identified using commercial PC assays (proband: PC antigen 42 u\\/dl, amidolytic activity 40 u\\/dl, anticoagulant activity 9 u\\/dl). The independent PROC nucleotide variations c.669C>A (predictive of Ser181Arg) and c.131C>T (predictive of Asn2Ile) segregated with the type I and type IIb PC deficiency phenotypes respectively, but co-segregated in the siblings with severe thrombosis. Soluble thrombomodulin (sTM)-mediated inhibition of plasma thrombin generation from an individual with PC-Asn2Ile was lower (endogenous thrombin potential (ETP) 56 +\\/- 1% that of ETP determined without sTM) than control plasma (ETP 15 +\\/- 2%) indicating reduced PC anticoagulant activity. Recombinant APC-Asn2Ile exhibited normal amidolytic activity but impaired anticoagulant activity. Protein S (PS)-dependent anticoagulant activity of recombinant APC-Asn2Ile and binding of recombinant APC-Asn2Ile to endothelial protein C receptor (EPCR) were reduced compared to recombinant wild-type APC. Asn2 lies within the omega-loop of the PC\\/APC Gla domain and this region is critical for calcium-induced folding and subsequent interactions with anionic phospholipids, EPCR and PS. The disruption of these interactions in this naturally-occurring PC variant highlights their collective importance in mediating APC anticoagulant activity in vivo.

  5. Acquired deficiencies of protein S. Protein S activity during oral anticoagulation, in liver disease, and in disseminated intravascular coagulation.

    OpenAIRE

    D'Angelo, A.; Vigano-D'Angelo, S; Esmon, C T; Comp, P C

    1988-01-01

    Protein S is a vitamin K-dependent plasma protein which serves as the cofactor for activated protein C. Protein S circulates in both an active, free form and in an inactive complex with C4b-binding protein. To elucidate the role of protein S in disease states and during oral anticoagulation, we developed a functional assay for protein S that permits evaluation of the distribution of protein S between free and bound forms and permits determination of the specific activity of the free protein S...

  6. Enhancement of rabbit protein S anticoagulant cofactor activity in vivo by modulation of the protein S C4B binding protein interaction.

    OpenAIRE

    Weinstein, R E; Walker, F. J.

    1990-01-01

    The carboxy-terminal region of protein S has been recently been observed to be involved in the interaction between protein S and C4b-binding protein (Walker, F. J. 1989. J. Biol. Chem. 264:17645-17658). A synthetic peptide, GVQLDLDEAI, corresponding to that region of protein S has been used to investigate the protein S/C4b-binding protein interaction in vitro and in vivo. Rabbit activated protein C possesses species-specific anticoagulant activity for which rabbit protein S functions as a cof...

  7. Plasma protein S contains zinc essential for efficient activated protein C-independent anticoagulant activity and binding to factor Xa, but not for efficient binding to tissue factor pathway inhibitor

    OpenAIRE

    Heeb, Mary J.; Prashun, Duane; Griffin, John H; Bouma, Bonno N.

    2009-01-01

    Protein S (PS) is a cofactor for activated protein C (APC), which inactivates coagulation factors (F) Va and VIIIa. Deficiency of protein C or PS is associated with risk of thrombosis. We found that PS also has APC-independent anticoagulant activity (PS-direct) and directly inhibits thrombin generated by FXa/FVa (prothrombinase complex). Here we report that PS contains Zn2+ that is required for PS-direct and that is lost during certain purification procedures. Immunoaffinity-purified PS conta...

  8. Heterofucans from Dictyota menstrualis have anticoagulant activity

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    I.R.L. Albuquerque

    2004-02-01

    Full Text Available Fucan is a term used to denote a family of sulfated L-fucose-rich polysaccharides which are present in the extracellular matrix of brown seaweed and in the egg jelly coat of sea urchins. Plant fucans have several biological activities, including anticoagulant and antithrombotic, related to the structural and chemical composition of polysaccharides. We have extracted sulfated polysaccharides from the brown seaweed Dictyota menstrualis by proteolytic digestion, followed by separation into 5 fractions by sequential acetone precipitation. Gel electrophoresis using 0.05 M 1,3-diaminopropane-acetate buffer, pH 9.0, stained with 0.1% toluidine blue, showed the presence of sulfated polysaccharides in all fractions. The chemical analyses demonstrated that all fractions are composed mainly of fucose, xylose, galactose, uronic acid, and sulfate. The anticoagulant activity of these heterofucans was determined by activated partial thromboplastin time (APTT using citrate normal human plasma. Only the fucans F1.0v and F1.5v showed anticoagulant activity. To prolong the coagulation time to double the baseline value in the APTT, the required concentration of fucan F1.0v (20 µg/ml was only 4.88-fold higher than that of the low molecular weight heparin Clexane® (4.1 µg/ml, whereas 80 µg/ml fucan 1.5 was needed to obtain the same effect. For both fucans this effect was abolished by desulfation. These polymers are composed of fucose, xylose, uronic acid, galactose, and sulfate at molar ratios of 1.0:0.8:0.7:0.8:0.4 and 1.0:0.3:0.4:1.5:1.3, respectively. This is the fist report indicating the presence of a heterofucan with higher anticoagulant activity from brown seaweed.

  9. Anticoagulant activity of original synthetic peptide derivatives.

    Science.gov (United States)

    Drozd, N N; Tolstenkov, A S; Makarov, V A; Miphtakhova, N T; Voyushina, T L; Sergeev, M E

    2008-01-01

    Original synthetic peptide derivatives exhibit anticoagulant activity in vitro and in vivo. They delayed fibrin clot formation from human blood plasma in tests for the intrinsic coagulation pathway (activated partial thromboplastin time) and final stage of plasma coagulation (thrombin time) and inhibited amidolytic activity of thrombin. We determined the minimum effective dose of the most active compound providing a 2-fold lengthening of blood clotting time (activated partial thromboplastin time test and thrombin time test), which persisted for 2-3 h. PMID:19024001

  10. Relationship between vitamin K dependent coagulation factors and anticoagulants (protein C and protein S) in neonatal vitamin K deficiency.

    OpenAIRE

    Matsuzaka, T; Tanaka, H.; Fukuda, M; Aoki, M.; Tsuji, Y; Kondoh, H

    1993-01-01

    To determine the relationship between vitamin K dependent coagulation factors and natural anticoagulants, namely protein C and protein S, in various degrees of vitamin K deficiency, plasma values for clotting activity, protein induced by vitamin K absence (PIVKA-II), protein C antigen, gamma-carboxy protein C antigen, and protein S antigen including total and free fractions and activity of protein C were measured in 66 full term and healthy breast fed neonates who did not receive vitamin K su...

  11. Anticoagulation inhibits tumor cell-mediated release of platelet angiogenic proteins and diminishes platelet angiogenic response.

    Science.gov (United States)

    Battinelli, Elisabeth M; Markens, Beth A; Kulenthirarajan, Rajesh A; Machlus, Kellie R; Flaumenhaft, Robert; Italiano, Joseph E

    2014-01-01

    Platelets are a reservoir for angiogenic proteins that are secreted in a differentially regulated process. Because of the propensity for clotting, patients with malignancy are often anticoagulated with heparin products, which paradoxically offer a survival benefit by an unknown mechanism. We hypothesized that antithrombotic agents alter the release of angiogenesis regulatory proteins from platelets. Our data revealed that platelets exposed to heparins released significantly decreased vascular endothelial growth factor (VEGF) in response to adenosine 5'-diphosphate or tumor cells (MCF-7 cells) and exhibited a decreased angiogenic potential. The releasate from these platelets contained decreased proangiogenic proteins. The novel anticoagulant fondaparinux (Xa inhibitor) demonstrated a similar impact on the platelet angiogenic potential. Because these anticoagulants decrease thrombin generation, we hypothesized that they disrupt signaling through the platelet protease-activated receptor 1 (PAR1) receptor. Addition of PAR1 antagonists to platelets decreased VEGF release and angiogenic potential. Exposure to a PAR1 agonist in the presence of anticoagulants rescued the angiogenic potential. In vivo studies demonstrated that platelets from anticoagulated patients had decreased VEGF release and angiogenic potential. Our data suggest that the mechanism by which antithrombotic agents increase survival and decrease metastasis in cancer patients is through attenuation of platelet angiogenic potential. PMID:24065244

  12. Chemically sulfated natural galactomannans with specific antiviral and anticoagulant activities.

    Science.gov (United States)

    Muschin, Tegshi; Budragchaa, Davaanyam; Kanamoto, Taisei; Nakashima, Hideki; Ichiyama, Koji; Yamamoto, Naoki; Shuqin, Han; Yoshida, Takashi

    2016-08-01

    Naturally occurring galactomannans were sulfated to give sulfated galactomannans with degrees of substitution of 0.7-1.4 per sugar unit and molecular weights of M¯n=0.6×10(4)-2.4×10(4). Sulfated galactomannans were found to have specific biological activities in vitro such as anticoagulant, anti-HIV and anti-Dengue virus activities. The biological activities were compared with those of standard dextran and curdlan sulfates, which are polysaccharides with potent antiviral activity and low cytotoxicity. It was found that sulfated galactomannans had moderate to high anticoagulant activity, 13.4-36.6unit/mg, compared to that of dextran and curdlan sulfates, 22.7 and 10.0unit/mg, and high anti-HIV and anti-Dengue virus activities, 0.04-0.8μg/mL and 0.2-1.1μg/mL, compared to those curdlan sulfates, 0.1μg/mL, respectively. The cytotoxicity on MT-4 and LCC-MK2 cells was low. Surface plasmon resonance (SPR) of sulfated galactomannans revealed strong interaction with poly-l-lysine as a model compound of virus proteins, and suggested that the specific biological activities might originate in the electrostatic interaction of negatively charged sulfate groups of sulfated galactomannans and positively charged amino groups of surface proteins of viruses. These results suggest that sulfated galactomannans effectively prevented the infection of cells by viruses and the degree of substitution and molecular weights played important roles in the biological activities. PMID:27154517

  13. Deficiency of the natural anticoagulant proteins in women with pregnancy related venous thromboembolism

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    Mitić Gorana

    2009-01-01

    Full Text Available Inherited thrombophilia can be defined as a predisposition to thrombosis caused by heritable defects, such as mutations in genes encoding the natural anticoagulants or clotting factors. Pregnancy related risk of VTE is sixfold increased comparing to non pregnant age matched women. Pregnancy is an independent risk factor for the development of venous thromboembolism and this risk is further increased by the presence of thrombophilia. Aim of the study: The aim of the study was to evaluate the association between deficiency of natural anticoagulants: antithrombin, protein C and protein S and pregnancy related thromboembolism. We have determined the activities of antithrombin, proten C and protein S in 74 women with pregnancy related thrombosis and in 45 healthy women who had at least two uncomplicated pregnancies. Among the women with the history of venous thromboembolism antithrombin deficiency was found in 4 (5.4%, protein C deficiency in 2 (2.7% and protein S deficiency in 5 (6.76%. The total of 11 (14.6% women was found to be deficient. Not a single woman in the control group was found to be deficient in natural anticoagulants. Deficiencies of coagulation inhibitors are associated with an increased risk of venous thrombosis during pregnancy and puerperium (p= 0.006. Antithrombin, protein C and protein S deficient women are at higher risk of developing venous thromboembolism during antepartal period (p= 0.0097. Prophylactic treatment with heparin should be recommended from the very beginning of the following pregnancy in women with antithrombin, protein C or protein S deficiency.

  14. Dilute Russell's viper venom and activated partial thromboplastin time in lupus anticoagulant diagnosis: is mixing essential?

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    Chandrashekar, Vani

    2016-06-01

    Dilute Russell's viper venom (DRVV) testing and activated partial thromboplastin time (APTT) have been effectively used in combination for lupus anticoagulant testing. The purpose of our study was to evaluate the role of mixing in activated partial thromboplastin and dilute Russell's viper venom testing for evaluation of lupus anticoagulants. Citrated blood from patients who were not on oral anticoagulant therapy was studied. Mixing study with 1 : 1 normal plasma for elevated APTT and also few samples with elevated screen time was carried out. Elevated APTT was seen in only 48.1% of patients with lupus anticoagulant. Correction of APTT was seen in 27.8% of lupus anticoagulant-positive patients. DRVV test on mixing resulted in 83.8% false-negative values. Integrated DRVV test could be a standalone test for testing lupus anticoagulant. Mixing study may be restricted for patients on oral anticoagulants or patients with strong lupus anticoagulant. PMID:26626041

  15. Improvements of anticoagulant activities of silk fibroin films with fucoidan

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Fucoidan (FC),an effective anticoagulant constituent extracted from brown algae,was introduced into silk fibroin (SF) for improving its blood compatibility.The SF and SF/FC blend films were characterized by attenuated total reflectance Fourier-transform infrared (ATR-FTIR),X-ray photoelectron spectroscopy (XPS),scanning electron microscopy (SEM) and dynamic contact angle determinator (CA).The in vitro anticoagulant activities of the films were evaluated by activated partial thromboplastin time (APTT),thrombin time (TT) and prothrombin time (PT) measurements.The endothelial cell attachment and proliferation viability on the film were assessed by micropipette aspiration technique and MTT assay,respectively.The testing results indicated that the introduction of FC increased the roughness,hydrophilicity and sulfate component of the film surface without impeding the formation of β-sheet conformation in SF.More important,FC brought excellent anticoagulant activity and better endothelial cell affinity to SF.The SF/FC blend film was hopeful to be used as blood-contacting biomaterials.

  16. Evidence of a protein C-like anticoagulant system in bony fish.

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    Salte, R; Norberg, K; Odegaard, O R

    1996-09-01

    Evidence is presented, confirming the presence of an anticoagulant system in the plasma of Atlantic salmon (Salmo salar L) and rainbow trout (Oncorhynchus mykiss Walbaum) (Order: Teleostei, Family: Salmonidae) that bears striking similarities with the protein C anticoagulant system in mammals; its vitamin K-dependence was documented through a warfarin feeding trial. A potent activator of this system is the protein C activator from the venom of the Central American Moccasin, Agkistrodon bilineatus. When activated, the system splits the tripeptide substrate glu-pro-arg-pNa, which is the substrate preferred for the in vitro assay of human protein C. It also prolongates the plasma activated partial thromboplastin time, indicating that the system is of clinical relevance. A temperature dependence of the plasma protein C-like activity was evident, the mean activity being 5- to 10-fold higher, but also more variable, in both species in summer and early fall, than it was in winter. There was also a species difference, with rainbow trout having the higher levels. In man, subnormal values of protein C implies an increased risk of thrombosis. Whether this applies to fish is not known. It is, however, a fact that microvascular thromboses are prevalent in farmed Atlantic salmon in winter, whereas thrombotic disease is not a problem in rainbow trout; in the present study plasma protein C-like activity was 30% (of a human reference plasma) in salmon at 4 degrees C compared to a level of 60% in rainbow trout. A complicating factor for the assay of protein C-like activity in salmonid plasma, is the poor stability of the inhibitory system upon storage. Consequently, assays have to be done with freshly prepared citrated plasma. PMID:8873347

  17. In-vitro anticoagulant activity of fucoidan derivatives from brown seaweed Laminaria japonica

    Institute of Scientific and Technical Information of China (English)

    WANG Jing; ZHANG Quanbin; ZHANG Zhongshan; HOU Yun; ZHANG Hong

    2011-01-01

    Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminariajaponica,an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT).The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content,sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.

  18. In-vitro anticoagulant activity of fucoidan derivatives from brown seaweed Laminaria japonica

    Science.gov (United States)

    Wang, Jing; Zhang, Quanbin; Zhang, Zhongshan; Hou, Yun; Zhang, Hong

    2011-05-01

    Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.

  19. Protein source and choice of anticoagulant decisively affect nanoparticle protein corona and cellular uptake

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    Schöttler, S.; Klein, Katja; Landfester, K.; Mailänder, V.

    2016-03-01

    Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance of the choice of protein source used for in vitro protein corona analysis is concisely investigated. Major and decisive differences in cellular uptake of a polystyrene nanoparticle incubated in fetal bovine serum, human serum, human citrate and heparin plasma are reported. Furthermore, the protein compositions are determined for coronas formed in the respective incubation media. A strong influence of heparin, which is used as an anticoagulant for plasma generation, on cell interaction is demonstrated. While heparin enhances the uptake into macrophages, it prevents internalization into HeLa cells. Taken together we can give the recommendation that human plasma anticoagulated with citrate seems to give the most relevant results for in vitro studies of nanoparticle uptake.Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance

  20. Protein source and choice of anticoagulant decisively affect nanoparticle protein corona and cellular uptake.

    Science.gov (United States)

    Schöttler, S; Klein, Katja; Landfester, K; Mailänder, V

    2016-03-14

    Protein adsorption on nanoparticles has been a focus of the field of nanocarrier research in the past few years and more and more papers are dealing with increasingly detailed lists of proteins adsorbed to a plethora of nanocarriers. While there is an urgent need to understand the influence of this protein corona on nanocarriers' interactions with cells the strong impact of the protein source on corona formation and the consequence for interaction with different cell types are factors that are regularly neglected, but should be taken into account for a meaningful analysis. In this study, the importance of the choice of protein source used for in vitro protein corona analysis is concisely investigated. Major and decisive differences in cellular uptake of a polystyrene nanoparticle incubated in fetal bovine serum, human serum, human citrate and heparin plasma are reported. Furthermore, the protein compositions are determined for coronas formed in the respective incubation media. A strong influence of heparin, which is used as an anticoagulant for plasma generation, on cell interaction is demonstrated. While heparin enhances the uptake into macrophages, it prevents internalization into HeLa cells. Taken together we can give the recommendation that human plasma anticoagulated with citrate seems to give the most relevant results for in vitro studies of nanoparticle uptake. PMID:26804616

  1. Simultaneous comparison of thrombogenic reactions to different combinations of anticoagulants, activated clotting times, and materials.

    Science.gov (United States)

    Nagai, Mirei; Iwasaki, Kiyotaka; Umezu, Mitsuo; Ozaki, Makoto

    2014-11-01

    Thrombogenic reactions under multiple interactions of pharmacological agents, doses, and materials have not been well understood yet. The aim of this study was to investigate the ability to simultaneously compare thrombogenic reactions to different combinations of anticoagulants, doses, and blood-contacting materials, in a single human blood using an in vitro test method. Four venous blood samples were drawn from each of six healthy volunteers into syringes that contained two different amounts of heparin and argatroban to set the activated clotting time (ACT) to approximately 200 or 500 s, respectively. The four blood samples from each volunteer were immediately poured into two clinical-grade extracorporeal circulation tubes: a polyvinyl chloride (PVC) tube and a poly(2-methoxyethyl acrylate)-coated (PMEA) PVC tube. These tubes with an inner diameter of 12.7 mm were rotated at 183 rpm in a 37°C chamber for 10 min. The results indicated that the in vitro thrombogenicity test method was capable of assessing differences in platelet factor 4 and β-thromboglobulin increases among different combinations of the two materials, two anticoagulants, and two ACTs. Higher amounts of total plasma proteins were absorbed on PVC tubes than on PMEA-coated tubes when using the same anticoagulant and dose. These data elucidate that the in vitro thrombogenicity test method is useful for the simultaneous quantitative evaluation of the influences of various combinations of materials, pharmacological agents, and doses on thrombogenicity in a single human blood. PMID:24652689

  2. Anticoagulant activities of piperlonguminine in vitro and in vivo

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    Wonhwa Lee

    2013-10-01

    Full Text Available Piperlonguminine (PL, an important component of Piperlongum fruits, is known to exhibit anti-hyperlipidemic, antiplateletand anti-melanogenic activities. Here, the anticoagulantactivities of PL were examined by monitoring activatedpartial-thromboplastin-time (aPTT, prothrombin-time (PT, andthe activities of thrombin and activated factor X (FXa. Theeffects of PL on the expressions of plasminogen activatorinhibitor type 1 (PAI-1 and tissue-type plasminogen activator(t-PA were also tested in tumor necrosis factor-α (TNF-αactivated HUVECs. The results showed that PL prolonged aPTTand PT significantly and inhibited the activities of thrombin andFXa. PL inhibited the generation of thrombin and FXa inHUVECs. In accordance with these anticoagulant activities, PLprolonged in vivo bleeding time and inhibited TNF-α inducedPAI-1 production. Furthermore, PAI-1/t-PA ratio was significantlydecreased by PL. Collectively, our results suggest that PLpossesses antithrombotic activities and that the current studycould provide bases for the development of new anticoagulantagents. [BMB Reports 2013; 46(10: 484-489

  3. Increased sulphation improves the anticoagulant activities of heparan sulphate and dermatan sulphate.

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    Ofosu, F A; Modi, G J; Blajchman, M A; Buchanan, M R; Johnson, E A

    1987-01-01

    Heparan sulphate and dermatan sulphate have both antithrombotic and anticoagulant properties. These are, however, significantly weaker than those of a comparable amount of standard pig mucosal heparin. Antithrombotic and anticoagulant effects of glycosaminoglycans depend on their ability to catalyse the inhibition of thrombin and/or to inhibit the activation of prothrombin. Since heparan sulphate and dermatan sulphate are less sulphated than unfractionated heparin, we investigated whether the decreased sulphation contributes to the lower antithrombotic and anticoagulant activities compared with standard heparin. To do this, we compared the anticoagulant activities of heparan sulphate and dermatan sulphate with those of their derivatives resulphated in vitro. The ratio of sulphate to carboxylate in these resulphated heparan sulphate and dermatan sulphate derivatives was approximately twice that of the parent compounds and similar to that of standard heparin. Anticoagulant effects were assessed by determining (a) the catalytic effects of each glycosaminoglycan on the inhibition of thrombin added to plasma, and (b) the ability of each glycosaminoglycan to inhibit the activation of 125I-prothrombin in plasma. The least sulphated glycosaminoglycans were least able to catalyse the inhibition of thrombin added to plasma and to inhibit the activation of prothrombin. Furthermore, increasing the degree of sulphation improved the catalytic effects of glycosaminoglycans on the inhibition of thrombin by heparin cofactor II in plasma. The degree of sulphation therefore appears to be an important functional property that contributes significantly to the anticoagulant effects of the two glycosaminoglycans. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:2963622

  4. Anticoagulant drugs increase natural killer cell activity in lung cancer

    Czech Academy of Sciences Publication Activity Database

    Bobek, M.; Boubelík, Michael; Fišerová, Anna; Luptovcová, Martina; Vannucci, Luca; Kacprzak, G.; Kolodzej, J.; Majewski, A.M.; Hoffman, R. M.

    2005-01-01

    Roč. 47, č. 2 (2005), s. 215-223. ISSN 0169-5002 Institutional research plan: CEZ:AV0Z5052915 Keywords : anticoagulant drugs * lung cancer * NK cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.172, year: 2005

  5. Comparison of Physicochemical Characteristics and Anticoagulant Activities of Polysaccharides from Three Sea Cucumbers

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    Shengmin Wang

    2013-02-01

    Full Text Available In order to search for sulfated polysaccharides in different invertebrate connective tissues and to examine their biological activities, we have isolated three types of polysaccharides from the body wall of the three sea cucumbers Holothuria edulis, Apostichopus japonicas and Holothuria nobilis. The physicochemical properties and anticoagulant activities of these polysaccharides were examined and compared. The chemical composition analysis and nuclear magnetic resonance (NMR analysis indicate that two types of polysaccharides, sulfated fucan and fucosylated chondroitin sulfate (FuCS, were found in all of the three species and in addition a neutral glycan was observed in H. edulis. The neutral α-glucan was firstly obtained from sea cucumber. The same type of polysaccharides from different species of sea cucumbers have similar physicochemical properties and anticoagulant activities, but those of different types of glycans are significantly different, possibly due to their different monosaccharide compositions, electric charges and average molecular weights. The FuCSs have stronger anticoagulant activities than the sulfated fucans, although the molecular sizes of the FuCSs are lower than those of the sulfated fucans, whereas the neutral glucan has no activity, as expected from the absence of sulfate. Thus, anticoagulant activities of the different type of polysaccharides are likely to relate to monosaccharide composition and sulfate content. Preliminary analysis suggests that the sulfation patterns of the FuCSs may result in the difference in anticoagulant activities. Our data could help elucidate the structure-activity relationship of the sea cucumber polysaccharides.

  6. Anticoagulant rodenticides.

    Science.gov (United States)

    Watt, Barbara E; Proudfoot, Alex T; Bradberry, Sally M; Vale, J Allister

    2005-01-01

    Anticoagulant pesticides are used widely in agricultural and urban rodent control. The emergence of warfarin-resistant strains of rats led to the introduction of a new group of anticoagulant rodenticides variously referred to as 'superwarfarins', 'single dose' or 'long-acting'. This group includes the second generation 4-hydroxycoumarins brodifacoum, bromadiolone, difenacoum, flocoumafen and the indanedione derivatives chlorophacinone and diphacinone. Most cases of anticoagulant rodenticide exposure involve young children and, as a consequence, the amounts ingested are almost invariably small. In contrast, intentional ingestion of large quantities of long-acting anticoagulant rodenticides may cause anticoagulation for several weeks or months. Occupational exposure has also been reported. Anticoagulant rodenticides inhibit vitamin K(1)-2,3 epoxide reductase and thus the synthesis of vitamin K and subsequently clotting factors II, VII, IX and X. The greater potency and duration of action of long-acting anticoagulant rodenticides is attributed to their: (i) greater affinity for vitamin K(1)-2,3-epoxide reductase; (ii) ability to disrupt the vitamin K(1)-epoxide cycle at more than one point; (iii) hepatic accumulation; and (iv) unusually long biological half-lives due to high lipid solubility and enterohepatic circulation. Substantial ingestion produces epistaxis, gingival bleeding, widespread bruising, haematomas, haematuria with flank pain, menorrhagia, gastrointestinal bleeding, rectal bleeding and haemorrhage into any internal organ; anaemia may result. Spontaneous haemoperitoneum has been described. Severe blood loss may result in hypovolaemic shock, coma and death. The first clinical signs of bleeding may be delayed and patients may remain anticoagulated for several days (warfarin) or days, weeks or months (long-acting anticoagulants) after ingestion of large amounts. There are now sufficient data in young children exposed to anticoagulant rodenticides to

  7. The factor XIIa blocking antibody 3F7: a safe anticoagulant with anti-inflammatory activities.

    Science.gov (United States)

    Worm, Marie; Köhler, Elodie C; Panda, Rachita; Long, Andy; Butler, Lynn M; Stavrou, Evi X; Nickel, Katrin F; Fuchs, Tobias A; Renné, Thomas

    2015-10-01

    The plasma protein factor XII (FXII) is the initiating protease of the procoagulant and proinflammatory contact system. FXII activates both the bradykinin (BK) producing kallikrein-kinin system and the intrinsic pathway of coagulation. Contact with negatively charged surfaces induces auto-activation of zymogen FXII that results in activated FXII (FXIIa). Various in vivo activators of FXII have been identified including heparin, misfolded protein aggregates, nucleic acids and polyphosphate. Murine models have established a central role of FXII in arterial and venous thromboembolic diseases. Despite the central function of FXII in pathologic thrombosis, its deficiency does not impair hemostasis in animals or humans. The selective role of FXIIa in thrombosis, but not hemostasis, offers an exciting novel strategy for safe anticoagulation based on interference with FXIIa. We have generated the recombinant fully human FXIIa-blocking antibody 3F7, which abolished FXIIa enzymatic activity and prevented thrombosis in a cardiopulmonary bypass system in large animals, in the absence of increased therapy-associated bleeding. Furthermore, 3F7 also interfered with BK-driven edema in the severe swelling disorder hereditary angioedema (HAE) type III. Taken together, targeting FXIIa with 3F7 appears to be a promising approach to treat edema disorders and thrombosis. PMID:26605293

  8. Antimicrobial and anticoagulant activities of the spine of stingray Himantura imbricata

    Institute of Scientific and Technical Information of China (English)

    Kaliyamoorthy Kalidasan; Velayudham Ravi; Sunil Kumar Sahu; Murugan Lakshmi Maheshwaran; Kathiresan Kandasamy

    2014-01-01

    Objective:To study the spine structure of stingray Himantura imbricata (H. imbricata) and to evaluate the anticoagulant properties of the spine extract obtained through various solvents extracts followed by antibacterial activity against human pathogens. Methods:Spines of H. imbricata were collected from Nagappattinam coast, Tamil Nadu, India and their spines were observed under the light microscope. The grounded spines were subjected to extraction of metabolites using methanol, ethanol, chloroform and acetone. Antibacterial activity was evaluated by disc diffusion technique against 10 human pathogens. Similarly, anticoagulant activity was also assessed by following United States Pharmacopeia method. Results:Light microscopic observation of spine revealed that the venom apparatus of the stingray H. imbricata consisted of two to three spines, glandular tissue and a sheath. The spine extract showed potent antibacterial activity against all tested pathogen. Maximum activity (14 mm) was found against Staphylococcus aureus. Crude extract showed 91.50 USP units/mg of anticoagulant activity. Conclusions: Microscopic observations gave new insight about the spine structure of the stingray. The spine extracts of H. imbricate showed potent activity against human pathogens revealed by the good zone of inhibition. Chloroform extracts conferred the most prominent antibacterial activity. The anticoagulant activity was also comparable with that of standard heparin.

  9. Antimicrobial and anticoagulant activities of the spine of stingray Himantura imbricata

    Directory of Open Access Journals (Sweden)

    Kaliyamoorthy Kalidasan

    2014-02-01

    Full Text Available Objective: To study the spine structure of stingray Himantura imbricata (H. imbricata and to evaluate the anticoagulant properties of the spine extract obtained through various solvents extracts followed by antibacterial activity against human pathogens. Methods: Spines of H. imbricata were collected from Nagappattinam coast, Tamil Nadu, India and their spines were observed under the light microscope. The grounded spines were subjected to extraction of metabolites using methanol, ethanol, chloroform and acetone. Antibacterial activity was evaluated by disc diffusion technique against 10 human pathogens. Similarly, anticoagulant activity was also assessed by following United States Pharmacopeia method. Results: Light microscopic observation of spine revealed that the venom apparatus of the stingray H. imbricata consisted of two to three spines, glandular tissue and a sheath. The spine extract showed potent antibacterial activity against all tested pathogen. Maximum activity (14 mm was found against Staphylococcus aureus. Crude extract showed 91.50 USP units/mg of anticoagulant activity. Conclusions: Microscopic observations gave new insight about the spine structure of the stingray. The spine extracts of H. imbricate showed potent activity against human pathogens revealed by the good zone of inhibition. Chloroform extracts conferred the most prominent antibacterial activity. The anticoagulant activity was also comparable with that of standard heparin.

  10. Biological Variations of Lupus Anticoagulant, Antithrombin, Protein C, Protein S, and von Willebrand Factor Assays.

    Science.gov (United States)

    Shou, Weiling; Chen, Qian; Wu, Wei; Cui, Wei

    2016-02-01

    The results of lupus anticoagulant (LA), antithrombin (AT), protein C (PC), and protein S (PS) testing, and the values of von Willebrand factor antigen (VWF:Ag) are important in diagnosis and therapeutic monitoring of thrombosis and hemostasis diseases. Till now, no published study has focused on the biological variations in LA testing, and only a few studies have examined the biological variations of AT, PC, PS, and VWF:Ag. With the latest fully automated instruments and improved reagents, the analytical, within-subject, and between-subject biological variations were estimated for these five coagulant parameters in a cohort of 25 apparently healthy subjects. Blood specimens were collected at 8:00 am, 12:00 pm, and 4:00 pm on days 1, 3, and 5. The analytical biological variation (CV(A)) values of all the parameters were less than 3%. The within-subject biological variation (CV(W)) and between-subject biological variation (CV(G)) values of the LA normalized ratio were 4.64 and 6.83%, respectively. No significant differences were observed in the intraday and interday biological variations of LA tests, or in AT, PC, PS, and VWF:Ag values. Additionally, the utility of the conventional population-based reference intervals of the five coagulation parameters was evaluated by the index of individuality, and data on CV(W) and CV(A) were used to calculate the reference change value to identify the significance of changes in serial results from the same individual. PMID:26516946

  11. Effects of extraction condition on structural features and anticoagulant activity of F. vesca L. conjugates.

    Science.gov (United States)

    Pawlaczyk, Izabela; Lewik-Tsirigotis, Marta; Capek, Peter; Matulová, Mária; Sasinková, Vlasta; Dąbrowski, Paweł; Witkiewicz, Wojciech; Gancarz, Roman

    2013-01-30

    From the air-dried Wild strawberry (Fragaria vesca L., family Rosaceae) leaves five water-soluble glycoconjugates Fv I-V by different extraction conditions have been isolated. Effects of extraction steps/agents on chemical composition and anticoagulant activity of Fv I-V were examined. Dark brown F. vesca conjugates Fv I-V were recovered in 4.5-8.4% yields, based on dry herb. Isolates were composed of carbohydrate, phenolic and protein components. Fv I-V displayed on HPLC broad molecule-mass distribution patterns with dominance of low molecule-masses 9-14 kDa. Their carbohydrate parts revealed high hexuronic acids content (35-60%) while the dominant neutral sugars - galactose, arabinose and rhamnose were found in lower amounts and indicated the presence of rhamnogalacturonans associated with arabinogalactans in all F. vesca preparations. In all Fv I-V isolates high polyphenolic contents were determined, whereas proteins were found in low amounts only. In in vitro experiments on human pooled plasma Fv I-V showed at higher concentrations complete inhibition of plasma clot formation and the most active conjugates in aPTT, PT and TT tests were shown to be Fv I and Fv III, containing the highest amounts of phenolics. PMID:23218362

  12. Antioxidant and anticoagulant activity of sulfated polysaccharide from Gracilaria debilis (Forsskal).

    Science.gov (United States)

    Sudharsan, Sadhasivam; Subhapradha, Namasivayam; Seedevi, Palaniappan; Shanmugam, Vairamani; Madeswaran, Perumal; Shanmugam, Annaian; Srinivasan, Alagiri

    2015-11-01

    Sulfated polysaccharide was isolated from Gracilaria debilis and purified through gel chromatography and their molecular weight was determined through AGE and PAGE. The total sugars in the crude, fractionated and purified polysaccharide were estimated as 52.65%, 59.70% and 67.60%, respectively. The ash and moisture content of crude and purified polysaccharide was found to be 14.2% and 23.5% and the polysaccharide was free from protein contamination. The sulfate and uronic acid contents in the crude, fractionated and purified were estimated as 14.08%, 15.33% and 16.01% and 10.12%, 13.56%, 16.70%. The elemental composition including carbon (crude - 23.12%, purified - 21.05%), hydrogen (crude - 3.4%, purified - 4.13%) and nitrogen (crude - 1.22%, purified - 0.56%) were also analyzed. The anticoagulant activity of the sulfated polysaccharide through APTT and PT was estimated at 14.11 and 8.23IU/mg. The purified polysaccharide with the molecular mass of 20kDa showed highest antioxidant activity (38.57%, 43.48% and 38.88%) in all the assays tested such as DPPH hydroxyl radical, superoxide radical, hydroxyl radical scavenging activities and the structural property was analyzed through FT-IR and (1)H NMR spectrum. The results together suggest that the isolated low molecular weight sulfated polysaccharide will demonstrate as a enormously available alternative natural source of antioxidant for industrial uses. PMID:26424206

  13. Increased anticoagulant activity of thrombin-binding DNA aptamers by nanoscale organization on DNA nanostructures

    OpenAIRE

    Rangnekar, Abhijit; Zhang, Alex M.; Shiyuan Li, Susan; M. Bompiani, Kristin; Hansen, Majken Nørgaard; Gothelf, Kurt Vesterager; Sullenger, Bruce A; LaBean, Thomas H.

    2012-01-01

    Control over thrombin activity is much desired to regulate blood clotting in surgical and therapeutic situations. Thrombin-binding RNA and DNA aptamers have been used to inhibit thrombin activity and thus the coagulation cascade. Soluble DNA aptamers, as well as two different aptamers tethered by a flexible single-strand linker, have been shown to possess anticoagulant activity. Here, we link multiple aptamers at programmed positions on DNA nanostructures to optimize spacing and orientation o...

  14. [Anticoagulant activity of low-molecular-weight heparins obtained using a hydrolase complex].

    Science.gov (United States)

    Drozd, N N; Tolstenkov, A S; Bannikova, G E; Miftakhova, N T; Lapikova, E S; Makarov, V A; Varlamov, V P

    2007-01-01

    The anticoagulant activity of low-molecular weight heparins (LMWH-PC) with average distribution of molecular weights within 3.4-5.8 kD was investigated. The samples of LMWH-PC were obtained from unfractionated heparin using immobilized enzyme complex of protease C. The LMWH-PC derivatives inhibited the activity of blood coagulation factors IIa (thrombin) and Xa. The LMWH-PC derivatives had an anti-factor-Xa activity up to 131-208 IU/mg and anti-factor-IIa activity up to 81-175 IU/mg. All LMWH-PC derivatives form complexes with protamine sulfate during electrophoresis in agarose gel. The anticoagulant activity of rabbit plasma exhibits a doze-dependent increase upon the intravenous or subcutaneous injection of LMWH-PC with a molecular weight of 5.4 kD. PMID:18318190

  15. Coagulant and anticoagulant activities of Bothrops lanceolatus (Fer de lance) venom.

    Science.gov (United States)

    Lôbo de Araújo, A; Kamiguti, A; Bon, C

    2001-01-01

    Bothrops lanceolatus venom contains caseinolytic, phospholipase, esterase and haemorrhagic activities. We have investigated the coagulant and anticoagulant actions of B. lanceolatus venom on human citrated plasma and on purified plasma components. Although B. lanceolatus venom up to 50 microg/ml was unable to clot citrated plasma, at concentrations > or = 5 microg/ml the venom dose-dependently clotted purified human fibrinogen, indicating the presence of a thrombin-like enzyme. Human plasma (final concentration > or = 12.5%) dose-dependently inhibited the venom-induced fibrinogen clotting. This finding suggested that endogenous plasma protease inhibitors can affect the venom's action on fibrinogen. To investigate this possibility, B. lanceolatus venom was incubated with different plasma protease inhibitors and the activity on fibrinogen tested. alpha(2)-Macroglobulin and alpha(1)-antitrypsin did not interfere with the coagulant activity of the venom whereas the antithrombin-III/heparin complex partially inhibited this activity. A non-toxic, acidic phospholipase A(2) purified from B. lanceolatus venom prolonged the activated partial thromboplastin time in human plasma from 39.7+/-0.5 s (control with saline) to 60.2+/-0.9 s with 50 microg of PLA(2) (p<0.001), suggesting an anticoagulant activity associated with this enzyme. This anticoagulant activity may account for some of the effects of the venom on blood coagulation. PMID:10978756

  16. An Antithrombin-Heparin Complex Increases the Anticoagulant Activity of Fibrin Clots

    Directory of Open Access Journals (Sweden)

    Lesley J. Smith

    2008-01-01

    Full Text Available Clotting blood contains fibrin-bound thrombin, which is a major source of procoagulant activity leading to clot extension and further activation of coagulation. When bound to fibrin, thrombin is protected from inhibition by antithrombin (AT + heparin but is neutralized when AT and heparin are covalently linked (ATH. Here, we report the surprising observation that, rather than yielding an inert complex, thrombin-ATH formation converts clots into anticoagulant surfaces that effectively catalyze inhibition of thrombin in the surrounding environment.

  17. The gene encoding vitamin K-dependent anticoagulant protein S is expressed in multiple rabbit organs as demonstrated by northern blotting, in situ hybridization, and immunohistochemistry.

    Science.gov (United States)

    He, X; Shen, L; Bjartell, A; Dahlbäck, B

    1995-01-01

    Vitamin K-dependent protein S is an anticoagulant plasma protein that functions as a co-factor to activated protein C in the degradation of coagulation factors Va and VIIIa. We investigated the tissue/cellular distribution of protein S synthesis by Northern blotting, in situ hybridization, and immunohistochemistry. Northern blotting together with in situ hybridization, using specific oligodeoxynucleotide probes, demonstrated protein S mRNA in liver, lung, testis, epididymis, ovary, uterus, and brain. In the reproductive system, protein S mRNA was present in the cytoplasm of Leydig cells, interstitial cells of the ovary, epithelial cells of the epididymis, and in the endometrium, including endometrial mucous glandular membrane in the myometrium. Bronchial epithelial cells and alveolar macrophages were positive in the respiratory system. In the central nervous system, pyramidal neurons in the cerebral cortex and in the hippocampal region, and dentate fascia neurons gave strongly positive signals. Immunohistochemistry with monoclonal antibodies yielded a staining pattern that correlated well with results of in situ hybridization. In conclusion, results from Northern blotting, in situ hybridization, and immunohistochemistry suggested that rabbit protein S is expressed in several extrahepatic tissues. The presence of protein S transcripts in these fully differentiated cells suggests a cell type-specific gene expression which may be related to local anticoagulation or to other as yet unknown protein S functions. PMID:7822769

  18. Depolymerized glycosaminoglycan and its anticoagulant activities from sea cucumber Apostichopus japonicus.

    Science.gov (United States)

    Yang, Jie; Wang, Yuanhong; Jiang, Tingfu; Lv, Lv; Zhang, Boyuan; Lv, Zhihua

    2015-01-01

    A controlled Cu(2+) catalytic free-radical depolymerization process of fucosylated chondroitin sulfate from sea cucumber Apostichopus japonicus was established. The results showed a good linear relationship between 1/Mw and time during the depolymerization. A series of fractions with different molecular weight were obtained, and the physicochemical properties of them were investigated and compared utilizing the chemical method, IR spectra and NMR spectra. The results showed no significant variations of the backbone and branches structures during the depolymerization. Furthermore, the anticoagulant activities of the depolymerized fractions were evaluated by the activated partial thromboplastin time (APTT). The APTT decreases in proportion to the molecular weight following a linear relationship and the prolongation of APTT activity requires at least oligosaccharide of 4 trisaccharide units (about 4000 Da). Their anticoagulant activity of low molecular weight fraction (Mw = 24,755 Da) is similar to LMWH with significantly less bleeding risk. The results suggest that the low molecular weight fraction could be used as a novel anticoagulant with less undesired side effects. PMID:25260572

  19. Antimicrobial and anticoagulant activities of the spine of stingray Himantura imbricata

    OpenAIRE

    Kaliyamoorthy Kalidasan; Velayudham Ravi; Sunil Kumar Sahu; Murugan Lakshmi Maheshwaran; Kathiresan Kandasamy

    2014-01-01

    Objective: To study the spine structure of stingray Himantura imbricata (H. imbricata) and to evaluate the anticoagulant properties of the spine extract obtained through various solvents extracts followed by antibacterial activity against human pathogens. Methods: Spines of H. imbricata were collected from Nagappattinam coast, Tamil Nadu, India and their spines were observed under the light microscope. The grounded spines were subjected to extraction of metabolites using m...

  20. Effect of atenolol and metoprolol on the anticoagulant activity of acenocoumarin

    OpenAIRE

    Mantero, F; Procidano, M.; Vicariotto, M. A.; Girolami, A.

    1984-01-01

    In patients receiving long-term acenocoumarin treatment, the effect on anticoagulant activity of atenolol (100 mg once-daily) and metoprolol (100 mg twice daily) was compared in a randomised within-patient open trial. No significant differences were demonstrated between mean prothrombin time and Thrombotest during treatment with atenolol, metoprolol or placebo. These data do not suggest the existence of an interaction between acenocoumarin and the moderately lipophilic β-adrenoceptor blocker ...

  1. Biological and Biochemical Potential of Sea Snake Venom and Characterization of Phospholipase A2 and Anticoagulation Activity.

    Science.gov (United States)

    Damotharan, Palani; Veeruraj, Anguchamy; Arumugam, Muthuvel; Balasubramanian, Thangavel

    2016-03-01

    This study is designed to isolate and purify a novel anti-clotting protein component from the venom of Enhydrina schistosa, and explore its biochemical and biological activities. The active protein was purified from the venom of E. schistosa by ion-exchange chromatography using DEAE-cellulose. The venom protein was tested by various parameters such as, proteolytic, haemolytic, phospholipase and anti-coagulant activities. 80 % purity was obtained in the final stage of purification and the purity level of venom was revealed as a single protein band of about 44 kDa in SDS-polyacrylamide electrophoresis under reducing conditions. The results showed that the Potent hemolytic activity was observed against cow, goat, chicken and human (A, B and O positive) erythrocytes. Furthermore, the clotting assays showed that the venom of E. schistosa significantly prolonged in activated partial thromboplastin time, thrombin time, and prothrombin time. Venomous enzymes which hydrolyzed casein and gelatin substrate were found in this venom protein. Gelatinolytic activity was optimal at pH 5-9 and (1)H NMR analysis of purified venom was the base line information for the structural determination. These results suggested that the E. schistosa venom holds good promise for the development of novel lead compounds for pharmacological applications in near future. PMID:26855489

  2. Purification, characterization and in vitro anticoagulant activity of polysaccharides from Gentiana scabra Bunge roots.

    Science.gov (United States)

    Cai, Weirong; Xu, Huiling; Xie, Liangliang; Sun, Jian; Sun, Taotao; Wu, Xiaoyan; Fu, Qinbao

    2016-04-20

    Three water-soluble polysaccharide fractions (GSP-1, GSP-2 and GSP-3) were obtained from Gentiana scabra Bunge roots by DEAE-Sepharose CL-6B and Sepharose CL-6B column chromatography. Their chemical characterizations were determined by high performance gel permeation chromatography (HPGPC), high performance anion exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) and Fourier transform infrared (FT-IR) spectrometer. Moreover, their in vitro anticoagulant activities were evaluated by activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) assays. GSP-1 and GSP-2 were composed of rhamnose, arabinose, galactose, glucose and galacturonic acid, while GSP-3 consisted of rhamnose, arabinose, galactose and galacturonic acid with a weight-average molecular weight of 5.8×10(4)Da. In comparison with the control group (saline), GSP, GSP-1, GSP-2 and GSP-3 could prolong APTT and TT, but not PT. Overall, GSP-3 exhibited potent anticoagulant activity and would be expected to be a potential source of anticoagulant. PMID:26876858

  3. Localization of anticoagulantly active heparan sulfate proteoglycans in vascular endothelium: Antithrombin binding on cultured endothelial cells and perfused rat aorta

    International Nuclear Information System (INIS)

    We have studied the interaction of 125I-antithrombin (125I-AT) with microvascular endothelial cells (RFPEC) to localize the cellular site of anticoagulantly active heparan sulfate proteoglycans (HSPG). The radiolabeled protease inhibitor bound specifically to the above HSPG with a Kd of approximately 50 nM. Confluent monolayer RFPEC cultures exhibited a linear increase in the amount of AT bound per cell for up to 16 d, whereas suspension RFPEC cultures possessed a constant number of protease inhibitor binding sites per cell for up to 5 d. These results suggest that monolayer RFPEC cultures secrete anticoagulantly active HSPG, which then accumulate in the extracellular matrix. This hypothesis was confirmed by quantitative light and EM level autoradiography which demonstrated that the AT binding sites are predominantly located in the extracellular matrix with only small quantities of protease inhibitor complexed to the cell surface. We have also pinpointed the in vivo position of anticoagulantly active HSPG within the blood vessel wall. Rat aortas were perfused, in situ, with 125I-AT, and bound labeled protease inhibitor was localized by light and EM autoradiography. The anticoagulantly active HSPG were concentrated immediately beneath the aortic and vasa vasorum endothelium with only a very small extent of labeling noted on the luminal surface of the endothelial cells. Based upon the above data, we propose a model whereby luminal and abluminal anticoagulantly active HSPG regulate coagulation mechanism activity

  4. Daboxin P, a Major Phospholipase A2 Enzyme from the Indian Daboia russelii russelii Venom Targets Factor X and Factor Xa for Its Anticoagulant Activity

    Science.gov (United States)

    Iyer, Janaki Krishnamurthy; Shih, Norrapat; Majumder, Munmi; Mattaparthi, Venkata Satish Kumar; Mukhopadhyay, Rupak; Doley, Robin

    2016-01-01

    In the present study a major protein has been purified from the venom of Indian Daboia russelii russelii using gel filtration, ion exchange and Rp-HPLC techniques. The purified protein, named daboxin P accounts for ~24% of the total protein of the crude venom and has a molecular mass of 13.597 kDa. It exhibits strong anticoagulant and phospholipase A2 activity but is devoid of any cytotoxic effect on the tested normal or cancerous cell lines. Its primary structure was deduced by N-terminal sequencing and chemical cleavage using Edman degradation and tandem mass spectrometry. It is composed of 121 amino acids with 14 cysteine residues and catalytically active His48 -Asp49 pair. The secondary structure of daboxin P constitutes 42.73% of α-helix and 12.36% of β-sheet. It is found to be stable at acidic (pH 3.0) and neutral pH (pH 7.0) and has a Tm value of 71.59 ± 0.46°C. Daboxin P exhibits anticoagulant effect under in-vitro and in-vivo conditions. It does not inhibit the catalytic activity of the serine proteases but inhibits the activation of factor X to factor Xa by the tenase complexes both in the presence and absence of phospholipids. It also inhibits the tenase complexes when active site residue (His48) was alkylated suggesting its non-enzymatic mode of anticoagulant activity. Moreover, it also inhibits prothrombinase complex when pre-incubated with factor Xa prior to factor Va addition. Fluorescence emission spectroscopy and affinity chromatography suggest the probable interaction of daboxin P with factor X and factor Xa. Molecular docking analysis reveals the interaction of the Ca+2 binding loop; helix C; anticoagulant region and C-terminal region of daboxin P with the heavy chain of factor Xa. This is the first report of a phospholipase A2 enzyme from Indian viper venom which targets both factor X and factor Xa for its anticoagulant activity. PMID:27089306

  5. Daboxin P, a Major Phospholipase A2 Enzyme from the Indian Daboia russelii russelii Venom Targets Factor X and Factor Xa for Its Anticoagulant Activity.

    Directory of Open Access Journals (Sweden)

    Maitreyee Sharma

    Full Text Available In the present study a major protein has been purified from the venom of Indian Daboia russelii russelii using gel filtration, ion exchange and Rp-HPLC techniques. The purified protein, named daboxin P accounts for ~24% of the total protein of the crude venom and has a molecular mass of 13.597 kDa. It exhibits strong anticoagulant and phospholipase A2 activity but is devoid of any cytotoxic effect on the tested normal or cancerous cell lines. Its primary structure was deduced by N-terminal sequencing and chemical cleavage using Edman degradation and tandem mass spectrometry. It is composed of 121 amino acids with 14 cysteine residues and catalytically active His48 -Asp49 pair. The secondary structure of daboxin P constitutes 42.73% of α-helix and 12.36% of β-sheet. It is found to be stable at acidic (pH 3.0 and neutral pH (pH 7.0 and has a Tm value of 71.59 ± 0.46°C. Daboxin P exhibits anticoagulant effect under in-vitro and in-vivo conditions. It does not inhibit the catalytic activity of the serine proteases but inhibits the activation of factor X to factor Xa by the tenase complexes both in the presence and absence of phospholipids. It also inhibits the tenase complexes when active site residue (His48 was alkylated suggesting its non-enzymatic mode of anticoagulant activity. Moreover, it also inhibits prothrombinase complex when pre-incubated with factor Xa prior to factor Va addition. Fluorescence emission spectroscopy and affinity chromatography suggest the probable interaction of daboxin P with factor X and factor Xa. Molecular docking analysis reveals the interaction of the Ca+2 binding loop; helix C; anticoagulant region and C-terminal region of daboxin P with the heavy chain of factor Xa. This is the first report of a phospholipase A2 enzyme from Indian viper venom which targets both factor X and factor Xa for its anticoagulant activity.

  6. Dissociation of activated protein C functions by elimination of protein S cofactor enhancement.

    LENUS (Irish Health Repository)

    Harmon, Shona

    2008-11-07

    Activated protein C (APC) plays a critical anticoagulant role in vivo by inactivating procoagulant factor Va and factor VIIIa and thus down-regulating thrombin generation. In addition, APC bound to the endothelial cell protein C receptor can initiate protease-activated receptor-1 (PAR-1)-mediated cytoprotective signaling. Protein S constitutes a critical cofactor for the anticoagulant function of APC but is not known to be involved in regulating APC-mediated protective PAR-1 signaling. In this study we utilized a site-directed mutagenesis strategy to characterize a putative protein S binding region within the APC Gla domain. Three single amino acid substitutions within the APC Gla domain (D35T, D36A, and A39V) were found to mildly impair protein S-dependent anticoagulant activity (<2-fold) but retained entirely normal cytoprotective activity. However, a single amino acid substitution (L38D) ablated the ability of protein S to function as a cofactor for this APC variant. Consequently, in assays of protein S-dependent factor Va proteolysis using purified proteins or in the plasma milieu, APC-L38D variant exhibited minimal residual anticoagulant activity compared with wild type APC. Despite the location of Leu-38 in the Gla domain, APC-L38D interacted normally with endothelial cell protein C receptor and retained its ability to trigger PAR-1 mediated cytoprotective signaling in a manner indistinguishable from that of wild type APC. Consequently, elimination of protein S cofactor enhancement of APC anticoagulant function represents a novel and effective strategy by which to separate the anticoagulant and cytoprotective functions of APC for potential therapeutic gain.

  7. Recombinant nematode anticoagulant protein c2 inhibits cell invasion by decreasing uPA expression in NSCLC cells.

    Science.gov (United States)

    Tong, Yu; Yue, Jun; Mao, Meng; Liu, Qingqing; Zhou, Jing; Yang, Jiyun

    2015-04-01

    Nematode anticoagulant protein c2 (NAPc2) is an 85-residue polypeptide originally isolated from the hematophagous hookworm, Ancylostoma caninum. Several studies have shown that rNAPc2 inhibits the growth of primary and metastatic tumors in mice independently of its ability to initiate coagulation. We obtained bioactive recombinant rNAPc2 by splicing of the rNAPc2-intein-CBD fusion proteins expressed in E. coli ER2566. In the in vitro assay, rNAPc2 obviously inhibited the invasive ability of non-small cell lung cancer (NSCLC) cells in a dose-dependent manner. Furthermore, rNAPc2 suppressed tumor growth in vivo by daily intraperitoneal injection of rNAPc2 in an NSCLC cell xenograft model of nude mice. Respectively, rNAPc2 downregulated the production of urokinase plasminogen activator (uPA) (P<0.05) and suppressed nuclear factor-κB (NF-κB) activity. We also identified that inhibition of NF-κB activity impaired cell invasion and reduced the uPA production in NSCLC cells. Meanwhile, NF-κB was found to directly bind to the uPA promoter in vitro. These results demonstrated that rNAPc2 inhibits cell invasion at least in part through the downregulation of the NF-κB-dependent metastasis-related gene expression in NSCLC. Our results also suggest that uPA, a known metastasis-promoting gene, is indirectly regulated by rNAPc2 through NF-κB activation. These results indicate that rNAPc2 may be a potent agent for the prevention of NSCLC progression. PMID:25672417

  8. Partial characterization and anticoagulant activity of a heterofucan from the brown seaweed Padina gymnospora

    Directory of Open Access Journals (Sweden)

    Silva T.M.A.

    2005-01-01

    Full Text Available The brown algae Padina gymnospora contain different fucans. Powdered algae were submitted to proteolysis with the proteolytic enzyme maxataze. The first extract of the algae was constituted of polysaccharides contaminated with lipids, phenols, etc. Fractionation of the fucans with increasing concentrations of acetone produced fractions with different proportions of fucose, xylose, uronic acid, galactose, and sulfate. One of the fractions, precipitated with 50% acetone (v/v, contained an 18-kDa heterofucan (PF1, which was further purified by gel-permeation chromatography on Sephadex G-75 using 0.2 M acetic acid as eluent and characterized by agarose gel electrophoresis in 0.05 M 1,3 diaminopropane/acetate buffer at pH 9.0, methylation and nuclear magnetic resonance spectroscopy. Structural analysis indicates that this fucan has a central core consisting mainly of 3-ß-D-glucuronic acid 1-> or 4-ß-D-glucuronic acid 1 ->, substituted at C-2 with alpha-L-fucose or ß-D-xylose. Sulfate groups were only detected at C-3 of 4-alpha-L-fucose 1-> units. The anticoagulant activity of the PF1 (only 2.5-fold lesser than low molecular weight heparin estimated by activated partial thromboplastin time was completely abolished upon desulfation by solvolysis in dimethyl sulfoxide, indicating that 3-O-sulfation at C-3 of 4-alpha-L-fucose 1-> units is responsible for the anticoagulant activity of the polymer.

  9. Antibacterial and anticoagulant activities of coumarins isolated from the flowers of Magydaris tomentosa.

    Science.gov (United States)

    Rosselli, Sergio; Maggio, Antonella; Bellone, Gabriella; Formisano, Carmen; Basile, Adriana; Cicala, Carla; Alfieri, Alessio; Mascolo, Nicola; Bruno, Maurizio

    2007-02-01

    The phytochemical investigation of the acetone and methanol extracts of the flowers of Magydaris tomentosa (Desf.) DC afforded six known coumarins as well as (+)-meranzin hydrate (7), not previously reported as a natural product. The antibacterial activity of umbelliprenin (1), osthol (2), imperatorin (3), citropten (4) and (+)-meranzin hydrate (7) was tested against Gram-positive and Gram-negative bacteria. All coumarins (1-7) isolated in this study inhibited growth of all bacterial strains tested (MIC between 16 and 256 microg/mL), the most active being imperatorin (3) (MICs between 32 and 128 microg/mL) and citropten (4) (MICs between 16 and 256 microg/mL). The anticoagulant activity of compounds 1-4 and 7 was also evaluated. PMID:17128388

  10. 正常妊娠妇女血中活化的蛋白C抵抗、狼疮样抗凝物质与血栓前状态分子标志物测定%Measurement of activated protein C resistance, lupus-like anticoagulant and prethrombotic markers in normal gestation

    Institute of Scientific and Technical Information of China (English)

    徐勇; 霍梅; 余涟; 叶素丹; 谢康云

    2001-01-01

    目的 研究活化的蛋白C抵抗(Activated protein Cresistance,APC-R)在正常妊娠中的发生情况,探讨狼疮抗凝物质(Lupus-like anticoagulant,LA)对妊娠性APC-R的影响及二者与凝血酶生成、继发性纤溶的关系。方法 采用APTT-APC法检测APC-R、dRVVT 法测定LA水平,并用ELISA法测定了凝血酶原片段F1+2和D-二聚体(D-dimer,D-D)的含量。结果 检测30例正常妇女对照(NC)和50例正常妊娠妇女,NC组APC-R比率为2.88±0.37,NP组为2.04±0.31(APC-R阳性率为42%);NC组LA阳性率为0,NP组为36.7%;NC组F1+2为(0.734±0.42)nmol/L,NP组为(1.05±0.69)nmol/L;NC组D-D为(0.48±0.05)mg/L,NP组为(0.63±0.11)mg/L;NP组的APC比率、F1+2和D-D的测定结果均较NC组有显著性差异。结论 妊娠可能发生与LA升高有关的APC-R,并导致了凝血酶激活物生成增加以及凝血酶、纤溶酶的激活和继发性纤溶的发生。%Objective To investigate the activated proteinCresistance(APC-R)occurred in normal pregnancy women and the effect of lupus-like anticoagulant(LA) on it,as well as to discuss the relationships between them and coagulation / fibrinolysis activation.Methods APC sensitivity ratio was assessed using APTT-APC method, LA was measured using dRVVT method,prothrombin fragment F1+2and D-dimer were assayed using ELISA Kits.Results 30 normal women controls(NC group)and 50 normal pregnancy women at 28~32 week's gestation(NP group)were measured.We found lower APC sensitivity ratio in normal group(2.04±0.31)than that in normal group (2.88±0.37).None LA positive was found in normal group but there were 36% LA positive samples in normal group.The F1+2and D-dimer levels in normal group were (0.73±0.42)nmol/L and (0.48±0.05)mg/L respectively,whereas were significant increased in NP group(1.05±0.69)nmol/L and (0.63±0.11)mg/L,respectively.Conclusion Normal gestation is associated with a decreased APC sensitivity ratio,which may be related to the increase of LA level

  11. [Anticoagulant activity of low-molecular-weight sulfated derivatives of galactomannan from Cyamopsis tetragonoloba (L.) seeds].

    Science.gov (United States)

    Mestechkina, N M; Shcherbukhin, V D; Bannikova, G E; Varlamov, V P; Drozd, N N; Tolstenkov, A S; Makarov, V A; Tikhonov, V E

    2008-01-01

    Galactomannan from seeds of Cyamopsis tetragonoloba (L.) Taub. (guar) was depolymerized using immobilized enzymatic preparation celloviridin. A set of fragments whose molecular weights varied from 12.6 to 245.6 kDa was obtained. Sulfated derivatives of components of all fractions were synthesized, in which the content of HSO3(-) groups was 48.05% +/- 2.31. All preparations exhibited anticoagulant activity, which was recorded in vitro in two tests--aIIa and aXa. The antithrombin activity (aIIa) was high (up to 65-87 U/mg) and did not depend on the molecular weight of a sulfated derivative; in the second test (aXa), the effect of molecular weight was observed. Biospecific electrophoresis allowed us to detect the ability of galactomannan sulfates to form complexes with protamine sulfate, a classic antidote to heparin. PMID:18491607

  12. Optimization of chemical sulfation, structural characterization and anticoagulant activity of Agaricus bisporus fucogalactan.

    Science.gov (United States)

    Román, Yony; Iacomini, Marcello; Sassaki, Guilherme L; Cipriani, Thales R

    2016-08-01

    A fucogalactan (E) was isolated from aqueous extract of Agaricus bisporus. The monosaccharide composition, methylation, and NMR analyses showed it is constituted by a (1→6)-linked α-d-Galp main-chain, partially methylated at O-3, and partially substituted at O-2 by non-reducing end-units of α-l-Fucp or α-d-Galp. HPSEC analysis showed it had Mw of 1.28×10(4)gmol(-1). The polysaccharide was sulfated modifying reaction time, molar ratio of sulfation agent to hydroxyl group on the polysaccharide (ηClSO3H/OH ratio), and ratio of total reaction volume to weight of sample (VT/w ratio; μLmg(-1)). The degree of substitution (DS) was evaluated for all sulfated derivatives. The sulfated fucogalactan with the highest DS value (2.83) had the best anticoagulant activity on Activated Partial Thromboplastin Time (APTT) and Protrombin Time (PT) assays. This sulfated fucogalactan, named E100, was obtained with the optimal conditions of ηClSO3H/OH ratio of 18, VT/w ratio of 100, in 6h of reaction. The results showed that E100 produces a linear increment of APTT for concentrations of 15-45μgmL(-1), whereas PT was almost constant between 20 and 400μgmL(-1), suggesting an anticoagulant activity via inhibition of the intrinsic pathway of blood coagulation. NMR and methylation analyses showed that α-d-Galp units of the main chain were greatly sulfated on 2-O-, 3-O-, and 4-O-positions. PMID:27112883

  13. Structural Features and Anti-coagulant Activity of the Sulphated Polysaccharide SPS-CF from a Green Alga Capsosiphon fulvescens

    Czech Academy of Sciences Publication Activity Database

    Synytsya, A.; Choi, D. J.; Pohl, Radek; Na, Y. S.; Capek, P.; Lattová, E.; Taubner, T.; Choi, J. W.; Lee, C. W.; Park, J. K.; Kim, W. J.; Kim, S. M.; Lee, J.; Park, Y. I.

    2015-01-01

    Roč. 17, č. 6 (2015), s. 718-735. ISSN 1436-2228 Institutional support: RVO:61388963 Keywords : alga Maesaengi (Capsosiphon fulvescens) * ulvan * monosaccharide composition * structure * anti-coagulant activity Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.269, year: 2014

  14. Study on extraction of agaropectin from Gelidium amansii and its anticoagulant activity

    Institute of Scientific and Technical Information of China (English)

    QI Huimin; LI Daxin; ZHANG Jingjing; LIU Li; ZHANG Quanbin

    2008-01-01

    Gelidium amansii agar was fractionated on DEAE-cellulose and four fractions were obtained sequentially.The yields of 1.0mol/L NaCl fraction and 2.5mol/L NaCl fraction were 2.80% and 2.03%.They are highly sulfated agar,and named as agaropectin with sulfate content being 22.8% and 32.5%,respectively.The anticoagulant experiment results show that agaropectin could effectively prolong the coagulation time in a dose-dependent manner in vitro.Agaropection could be absorbed and effectively prolong the plasma coagulation time in vivo.After intragastric administration at the doses of 100,200,and 400mg/kg·d in rats for 15 days,TT (thrombin time),CT (coagulation time),PT (prothrombin time),and APTT (activated partial thromboplastin time) could be effectively prolonged and the plasma Fib level could be significantly lowered.

  15. Novel branch patterns and anticoagulant activity of glycosaminoglycan from sea cucumber Apostichopus japonicus.

    Science.gov (United States)

    Yang, Jie; Wang, Yuanhong; Jiang, Tingfu; Lv, Zhihua

    2015-01-01

    A novel glucosidic pattern of fucose branches was found in the glycosaminoglycan from the sea cucumber Apostichopus japonicus in China. The methylation of desulfated/carboxyl-reduced polysaccharides and analysis of unsaturated disaccharides generated from the enzymolysis of the defucosed polysaccharides demonstrated that the branch is formed by one fucopyranosyl residue, 46.5% of which is linked through the O-3 position of β-D-glucuronic acid, while 8.7% and 43.9% are linked through the O-6 and O-4 positions of the N-acetylgalactosamine moiety. The β-D-glucuronic acid, N-acetyl-β-D-galactosamine, α-L-fucose and sulfate ester with the molecular ratio of 0.97:1.00:1.13:3.85 composed the backbone → 4)GlcUAβ(1 → 3)GalNAcβ(1 → and sulfated fucose branches. The sulfation patterns of fucose branches and the linkage pattern of the backbone structure were determined by 1/2 dimension NMR. The most abundant branch species were 2,4-di-O-sulfated and 3,4-di-O-sulfated fucose, but 4-mono-O-sulfated residue was also present. The structure of presently obtained glycosaminoglycan is different from that previously obtained from Stichopus japonicus (Kariya et al., Carbohyd. Res. 297 (1997) 273-279), which suggests that the structures of glycosaminoglycans from the same species of different regions somehow differ. The anticoagulant assay indicated that the polysaccharide possessed a high anticoagulant activity and the sulfated fucose branches were essential to the activity. PMID:25453278

  16. Effect of lysine clonixinate on the pharmacokinetics and anticoagulant activity of phenprocoumon.

    Science.gov (United States)

    Russmann, S; Dilger, K; Trenk, D; Nagyivanyi, P; Jähnchen, E

    2001-11-01

    The effect of the non-steroidal anti-inflammatory drug lysine clonixinate ([2-(3-chloro-o-toluidino)nicotinic acid]-L-lysinate, CAS 55837-30-4) on the pharmacokinetics and anticoagulant activity of phenprocoumon (4-hydroxy-3-(1-phenylpropyl)-coumarin, CAS 435-97-2) was investigated in an open, randomised, two-fold, cross-over study in 12 healthy male volunteers. These subjects received a single dose of 18 mg phenprocoumon without or with concomitant treatment with lysine clonixinate (125 mg five times a day for 3 days before and 13 days after ingestion of a single dose of phenprocoumon). Pharmacokinetic parameters of phenprocoumon following oral administration were: CL/f: 0.779 +/- 0.157 ml/min, half-life of elimination: 147.2 +/- 19.9 h; free fraction in serum: 0.51 +/- 0.20%. These parameters were not significantly altered by concomitant treatment with lysine clonixinate. Prothrombin time increased from 13.3 +/- 1.3 s (at time 0) to 17.7 +/- 2.7 s following phenprocoumon and from 13.3 +/- 1.2 s to 18.0 +/- 2.2 s following combined administration. Prothrombin time returned to the pretreatment values 240 h after administration of phenprocoumon. The integrated effect (AUEC0-288 h) was identical following both treatments (4.303 +/- 461 and 4.303 +/- 312 s x h for phenprocoumon alone and phenprocoumon with lysine clonixinate, respectively). Thus, lysine clonixinate administered in therapeutic doses does not affect the pharmacokinetics and anticoagulant activity of phenproxoumon. PMID:11765590

  17. Synthesis and in Vitro and in Vivo Anticoagulant and Antiplatelet Activities of Amidino- and Non-Amidinobenzamides

    Directory of Open Access Journals (Sweden)

    Soo Hyun Lee

    2016-05-01

    Full Text Available Three amidino- and ten non-amidinobenzamides were synthesized as 3-aminobenzoic acid scaffold-based anticoagulant and antiplatelet compounds. The anticoagulant activities of thirteen synthesized compounds 1–13, and 2b and 3b as prodrugs were preliminary evaluated by screening the prolongation of activated partial thromboplastin time (aPTT and prothrombin time (PT in vitro. From the aPTT results obtained, two amidinobenzamides, N-(3′-amidinophenyl-3-(thiophen-2′′-ylcarbonylamino benzamide (1, 33.2 ± 0.7 s and N-(4′-amidinophenyl-3-(thiophen-2′′-ylcarbonylamino benzamide (2, 43.5 ± 0.6 s were selected to investigate the further anticoagulant and antiplatelet activities. The aPTT results of 1 (33.2 ± 0.7 s and 2 (43.5 ± 0.6 s were compared with heparin (62.5 ± 0.8 s in vitro at 30 μM. We investigated the effect of 1 and 2 on blood anticoagulant activity (ex vivo and on tail bleeding time (in vivo on mice. A tail cutting/bleeding time assay revealed that both 1 and 2 prolonged bleeding time in mice at a dose of 24.1 g/mouse and above. Compounds 1 and 2 dose-dependently inhibited thrombin-catalyzed fibrin polymerization and platelet aggregation. In addition, 1 and 2 were evaluated on the inhibitory activities of thrombin and FXa as well as the generation of thrombin and FXa in human umbilical vein endothelial cells (HUVECs. Collectively, 1 and 2 possess some antiplatelet and anticoagulant activities and offer a basis for development of a novel antithrombotic product.

  18. Characterization of cDNA encoding human placental anticoagulant protein (PP4): Homology with the lipocortin family

    International Nuclear Information System (INIS)

    A cDNA library prepared from human placenta was screened for sequences encoding the placental protein 4 (PP4). PP4 is an anticoagulant protein that acts as an indirect inhibitor of the thromboplastin-specific complex, which is involved in the blood coagulation cascade. Partial amino acid sequence information from PP4-derived cyanogen bromide fragments was used to design three oligonucleotide probes for screening the library. From 106 independent recombinants, 18 clones were identified that hybridized to all three probes. These 18 recombinants contained cDNA inserts encoding a protein of 320 amino acid residues. In addition to the PP4 cDNA the authors identified 9 other recombinants encoding a protein with considerable similarity (74%) to PP4, which was termed PP4-X. PP4 and PP4-X belong to the lipocortin family, as judged by their homology to lipocortin I and calpactin I

  19. Anticoagulant, Antioxidant and Antitumor Activities of Heterofucans from the Seaweed Dictyopteris delicatula

    Directory of Open Access Journals (Sweden)

    Hugo Alexandre Oliveira Rocha

    2011-05-01

    Full Text Available In the present study, six families of sulfated polysaccharides were obtained from seaweed Dictyopteris delicatula by proteolytic digestion, followed by acetone fractionation and molecular sieving on Sephadex G-100. Chemical analyses demonstrated that all polysaccharides contain heterofucans composed mainly of fucose, xylose, glucose, galactose, uronic acid, and sulfate. The fucans F0.5v and F0.7v at 1.0 mg/mL showed high ferric chelating activity (~45%, whereas fucans F1.3v (0.5 mg/mL showed considerable reducing power, about 53.2% of the activity of vitamin C. The fucan F1.5v presented the most prominent anticoagulant activity. The best antiproliferative activity was found with fucans F1.3v and F0.7v. However, F1.3v activity was much higher than F0.7v inhibiting almost 100% of HeLa cell proliferation. These fucans have been selected for further studies on structural characterization as well as in vivo experiments, which are already in progress.

  20. Lupus anticoagulant, disease activity and low complement in the first trimester are predictive of pregnancy loss

    OpenAIRE

    Mankee, Anil; Petri, Michelle; Magder, Laurence S.

    2015-01-01

    Introduction Multiple factors, including proteinuria, antiphospholipid syndrome, thrombocytopenia and hypertension, are predictive of pregnancy loss in systemic lupus erythematosus (SLE). In the PROMISSE study of predictors of pregnancy loss, only a battery of lupus anticoagulant tests was predictive of a composite of adverse pregnancy outcomes. We examined the predictive value of one baseline lupus anticoagulant test (dilute Russell viper venom time) with pregnancy loss in women with SLE. Me...

  1. Anticoagulant activity of a sulfated polysaccharide isolated from the green seaweed Caulerpa cupressoides

    Directory of Open Access Journals (Sweden)

    José Ariévilo Gurgel Rodrigues

    2011-08-01

    Full Text Available The aim of this study was to evaluate certain molecular characteristics of a sulfated polysaccharide (SPs with anticoagulant properties, isolated from Caulerpa cupressoides (Chlorophyta. Crude SPs were extracted by proteolytic digestion (papain, followed by ion-exchange chromatography on a DEAE-cellulose column. The fractions obtained were analyzed for molecular mass, 0.5% agarose gel electrophoresis and chemical composition. The activated partial thromboplastin time (APTT test was applied using normal human plasma and standard heparin (HEP (193 IU mg-1. The yield was ~ 3%, and the chromatography procedure separated the material into three different SP fractions (F I, F II and F III, eluted at the concentrations of 0.50, 0.75 and 1.00 M of NaCl, respectively. Only fraction F II was active (24.62 IU mg-1, with high sulfate content (23.79% and number of molecular mass peaks. Therefore, the APTT of a fraction isolated from C. cupressoides was less potent than HEP.

  2. Anticoagulant and antithrombotic activities of low-molecular-weight propylene glycol alginate sodium sulfate (PSS).

    Science.gov (United States)

    Xin, Meng; Ren, Li; Sun, Yang; Li, Hai-hua; Guan, Hua-Shi; He, Xiao-Xi; Li, Chun-Xia

    2016-05-23

    Propylene glycol alginate sodium sulfate (PSS), a sulfated polysaccharide derivative, has been used as a heparinoid drug to prevent and treat hyperlipidemia and ischemic cardio-cerebrovascular diseases in China for nearly 30 years. To extend the applications of PSS, a series of low-molecular-weight PSSs (named FPs) were prepared by oxidative-reductive depolymerization, and the antithrombotic activities were investigated thoroughly in vitro and in vivo. The bioactivity evaluation demonstrated a positive correlation between the molecular weight and the anticoagulant and antithrombotic activities of FPs. FPs could prolong the APTT and clotting time and reduce platelet aggregation significantly. FPs could also effectively inhibit factor IIa in the presence of AT-III and HC-II. FPs decreased the wet weights and lengths of the thrombus and increased occlusion times in vivo. FP-6k, a PSS fragment with a molecular weight of 6 kDa, is an optimal antithrombotic candidate for further study and showed little chance for hemorrhagic action. PMID:26974373

  3. [Effects of intravenous injection of sulphated galactomannan on anticoagulant activity of rat plasma].

    Science.gov (United States)

    Drozd, N N; Makarov, V A; Tolstenkov, A S; Lapikova, E S; Miftakhova, N T; Mestechkina, N M; Shcherbukhin, V D; Il'ina, A V; Varlamov, V P

    2008-01-01

    We studied anticoagulant activity in vitro and in vivo of sulfate depolymerisation galactomannan guar with the following characteristics: Man:Gal 1.64, molecular mass 127 kDa, sulfation degree 1.46. We found the ability of galactomannan-HSO3Na (GM) to increase the time of blood coagulation in the test aPTT with an increase of its concentration and to decrease velocity of chromogenic substrate on the factor Xa hydrolysis. Specific antithrombin and anti-factor Xa activities of GM were 35.8 +/- 1.8 IU/mg and 6.6 +/- 0.5 IU/mg, respectively. In biospecific electrophoresis complexes arise between GM and protamine sulfate. Intravenous injection of GM to rats prolonged plasma coagulation time in the aPTT test with dose reduction from 1 to 3 mg/kg. In rat thrombosis model a dose of 3 Mg/kg produced a 100% inhibition of blood clot. PMID:18946908

  4. Heterofucans from the Brown Seaweed Canistrocarpus cervicornis with Anticoagulant and Antioxidant Activities

    Directory of Open Access Journals (Sweden)

    Hugo Alexandre Oliveira Rocha

    2011-01-01

    Full Text Available Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated L-fucose. We extracted six fucans from Canistrocarpus cervicornis by proteolytic digestion followed by sequential acetone precipitation. These heterofucans are composed mainly of fucose, glucuronic acid, galactose and sulfate. No polysaccharide was capable of prolonging prothrombin time (PT at the concentration assayed. However, all polysaccharides prolonged activated partial thromboplastin time (aPTT. Four sulfated polysaccharides (CC-0.3/CC-0.5/CC-0.7/CC-1.0 doubled aPTT with only 0.1 mg/mL of plasma, only 1.25-fold less than Clexane®, a commercial low molecular weight heparin. Heterofucans exhibited total antioxidant capacity, low hydroxyl radical scavenging activity, good superoxide radical scavenging efficiency (except CC-1.0, and excellent ferrous chelating ability (except CC-0.3. These results clearly indicate the beneficial effect of C. cervicornis polysaccharides as anticoagulants and antioxidants. Further purification steps and additional studies on structural features as well as in vivo experiments are needed to test the viability of their use as therapeutic agents.

  5. Citrate confers less filter-induced complement activation and neutrophil degranulation than heparin when used for anticoagulation during continuous venovenous haemofiltration in critically ill patients

    OpenAIRE

    Schilder, Louise; Nurmohamed, Shaikh Azam; Wee, Piet; Paauw, Nanne; Girbes, Armand; Beishuizen, Albertus; Beelen, Robert; Groeneveld, Johan

    2014-01-01

    textabstractBackground: During continuous venovenous haemofiltration (CVVH), regional anticoagulation with citrate may be superior to heparin in terms of biocompatibility, since heparin as opposed to citrate may activate complement (reflected by circulating C5a) and induce neutrophil degranulation in the filter and myeloperoxidase (MPO) release from endothelium. Methods. No anticoagulation (n = 13), unfractionated heparin (n = 8) and trisodium citrate (n = 17) regimens during CVVH were compar...

  6. Citrate confers less filter-induced complement activation and neutrophil degranulation than heparin when used for anticoagulation during continuous venovenous haemofiltration in critically ill patients

    OpenAIRE

    Schilder, Louise; Nurmohamed, S Azam; ter Wee, Pieter M.; Paauw, Nanne J.; Girbes, Armand RJ; Beishuizen, Albertus; Beelen, Robert HJ; Groeneveld, AB Johan

    2014-01-01

    Background During continuous venovenous haemofiltration (CVVH), regional anticoagulation with citrate may be superior to heparin in terms of biocompatibility, since heparin as opposed to citrate may activate complement (reflected by circulating C5a) and induce neutrophil degranulation in the filter and myeloperoxidase (MPO) release from endothelium. Methods No anticoagulation (n = 13), unfractionated heparin (n = 8) and trisodium citrate (n = 17) regimens during CVVH were compared. Blood samp...

  7. The assessment of anticoagulant activity to predict bleeding outcome in atrial fibrillation patients receiving dabigatran etexilate.

    Science.gov (United States)

    Chang, Yao-Ting; Hu, Yu-Feng; Liao, Jo-Nan; Chern, Chang-Ming; Lin, Yenn-Jiang; Chang, Shih-Lin; Wu, Cheng-Hsueh; Sung, Shih-Hsien; Wang, Kang-Ling; Lu, Tse-Min; Chao, Tze-Fan; Lo, Li-Wei; Hsu, Li-Chi; Chung, Chih-Ping; Chang, Peter M-H; Hsu, Wei-Hsuan; Chiou, Chuen-Wang; Chen, Shih-Ann

    2016-06-01

    Special circumstances may require the measurement of the anticoagulant effect of dabigatran etexilate. No data currently link any given coagulation test to bleeding outcomes in patients receiving dabigatran etexilate for atrial fibrillation. Nonvalvular atrial fibrillation patients receiving dabigatran etexilate of 110 mg (DE110) or 150 mg (DE150) were consecutively enrolled. The hemoclot thrombin inhibitor (HTI) assay, prothrombin time, and activated partial thromboplastin time (APTT) measurements were correlated with bleeding events during a prospective follow-up. There were 17 bleeding events (8.2%) in 208 patients (74.7 ± 10.3 years old, 67.9% male, median follow-up: 364 days), whereas 15 patients with bleeding events used DE110. Compared with DE110, the patients receiving DE150 were younger and more often male and had lower HAS-BLED and CHA2DS2VASc scores and better renal function. Patients' HTI levels were very variable (DE110, 10-90th percentile: 20.5-223.9 ng/ml). A receiver-operator characteristic curve gave a median cutoff HTI level of 117.7 ng/ml to predict bleeding events (C-statistics: 0.65; P = 0.036), but no cutoff could be determined for prothrombin time or APTT. Based on the Kaplan-Meier analysis, a dabigatran etexilate level greater than 117.7 ng/ml was associated with a higher bleeding rate (15.4% vs. 4.9%, P = 0.01). After multivariate Cox regression analysis, HTI levels, history of stroke, and male sex were independent risk factors for bleeding events. Dabigatran etexilate-HTI levels were independently associated with bleeding in patients receiving routine clinical care. Blood sampling at multiple time points might be needed to increase reliability because of high variation of dabigatran etexilate-HTI levels. PMID:26991859

  8. In Vitro Antioxidant, Anticoagulant and Antimicrobial Activity and in Inhibition of Cancer Cell Proliferation by Xylan Extracted from Corn Cobs

    Directory of Open Access Journals (Sweden)

    Hugo Alexandre Oliveira Rocha

    2011-12-01

    Full Text Available Xylan is one of most abundant polymer after cellulose. However, its potential has yet to be completely recognized. Corn cobs contain a considerable reservoir of xylan. The aim of this work was to study some of the biological activities of xylan obtained from corn cobs after alkaline extraction enhanced by ultrasonication. Physical chemistry and infrared analyses showed 130 kDa heteroxylan containing mainly xylose:arabinose: galactose:glucose (5.0:1.5:2.0:1.2. Xylan obtained exhibited total antioxidant activity corresponding to 48.5 mg of ascorbic acid equivalent/g of xylan. Furthermore, xylan displayed high ferric chelating activity (70% at 2 mg/mL. Xylan also showed anticoagulant activity in aPTT test. In antimicrobial assay, the polysaccharide significantly inhibited bacterial growth of Klebsiella pneumoniae. In a test with normal and tumor human cells, after 72 h, only HeLa tumor cell proliferation was inhibited (p < 0.05 in a dose-dependent manner by xylan, reaching saturation at around 2 mg/mL, whereas 3T3 normal cell proliferation was not affected. The results suggest that it has potential clinical applications as antioxidant, anticoagulant, antimicrobial and antiproliferative compounds.

  9. Platelet protein S directly inhibits procoagulant activity on platelets and microparticles

    OpenAIRE

    Stavenuiter, Fabian; Davis, Nicole F.; Duan, Erning; Gale, Andrew J.; Heeb, Mary J.

    2012-01-01

    Anticoagulant plasma protein S (PS) is essential for maintaining hemostatic balance. About 2.5% of PS is stored in platelets and released upon platelet stimulation. So far, little is known about the functionality and importance of platelet (plt)PS. A platelet-associated protease cleaves plasma-derived (pd)PS and pltPS in the “thrombin-sensitive region”, abolishing activated protein C (APC) cofactor activity. However we showed that cleaved PS retains APC-independent anticoagulant activities (“...

  10. Effects of L-arginine immobilization on the anticoagulant activity and hemolytic property of polyethylene terephthalate films

    Energy Technology Data Exchange (ETDEWEB)

    Liu Yun, E-mail: liuy@tgrc.org [Department of Chemistry, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China); Yang Yun [Department of Chemistry, School of Science, Xi' an Jiaotong University, Xi' an 710049 (China); Wu Feng [Research Centre of Blood, College of Medicine, Xi' an Jiaotong University, Xi' an 710065 (China)

    2010-04-01

    Surface modification of polyethylene terephthalate (PET) films was performed with L-arginine (L-Arg) to gain an improved anticoagulant surface. The surface chemistry changes of modified films were characterized by X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The in vitro anticoagulant activities of the surface-modified PET films were evaluated by blood clotting test, hemolytic test, and the measurement of clotting time including plasma recalcification time (PRT), activated partial thromboplastin time (APTT), and prothrombin time (PT). The data of blood coagulation index (BCI) for L-arginine modified PET films (PET-Arg) was larger than that for PET at the same blood-sample contact time. The hemolysis ratio for PET-Arg was less than that for PET and within the accepted standard for biomaterials. The PRT and APTT for PET-Arg were significantly prolonged by 189 s and 25 s, respectively, compared to those for the unmodified PET. All results suggested that the currently described modification method could be a possible candidate to create antithrombogenic PET surfaces which would be useful for further medical applications.

  11. Effects of L-arginine immobilization on the anticoagulant activity and hemolytic property of polyethylene terephthalate films

    International Nuclear Information System (INIS)

    Surface modification of polyethylene terephthalate (PET) films was performed with L-arginine (L-Arg) to gain an improved anticoagulant surface. The surface chemistry changes of modified films were characterized by X-ray photoelectron spectroscopy (XPS) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. The in vitro anticoagulant activities of the surface-modified PET films were evaluated by blood clotting test, hemolytic test, and the measurement of clotting time including plasma recalcification time (PRT), activated partial thromboplastin time (APTT), and prothrombin time (PT). The data of blood coagulation index (BCI) for L-arginine modified PET films (PET-Arg) was larger than that for PET at the same blood-sample contact time. The hemolysis ratio for PET-Arg was less than that for PET and within the accepted standard for biomaterials. The PRT and APTT for PET-Arg were significantly prolonged by 189 s and 25 s, respectively, compared to those for the unmodified PET. All results suggested that the currently described modification method could be a possible candidate to create antithrombogenic PET surfaces which would be useful for further medical applications.

  12. 海南水蛭中水蛭素的抗凝活性研究%Study on anticoagulant activity of hirudin in Hainan leech

    Institute of Scientific and Technical Information of China (English)

    刘腾; 符乃光; 李泽友

    2015-01-01

    目的:分析海南水蛭的品种及其中水蛭素的抗凝作用。方法观察海南水蛭的形态特征、薄层色谱图,并采用凝血酶滴定法测定其抗凝活性。结果海南水蛭为菲牛蛭,水蛭素的抗凝活性分别为:全身1174.8 U/g、头部6521.7 U/g、身体308.6 U/g。结论海南水蛭具有很好的抗凝血活性,值得进一步研究开发。%Objective To analyze the species of Hainan leeches and the anticoagulant activity of hirudin. Methods The morphological characteristics and thin-layer chromatogram of Hainan leech were observed. Then anti-coagulant activity was measured with the method of thrombin titration. Results Hainan leeches were Hirudinaria ma-nillensis. The anticoagulant activity of Hainan Leech hirudin was 1 174.8 U/g of whole body, 6 521.7 U/g of the head and 308.6 U/g of the body. Conclusion Hainan leeches have very good anticoagulant activity, which deserve further research and development.

  13. Chemical structure and anticoagulant activity of highly pyruvylated sulfated galactans from tropical green seaweeds of the order Bryopsidales.

    Science.gov (United States)

    Arata, Paula X; Quintana, Irene; Canelón, Dilsia J; Vera, Beatriz E; Compagnone, Reinaldo S; Ciancia, Marina

    2015-05-20

    Sulfated and pyruvylated galactans were isolated from three tropical species of the Bryopsidales, Penicillus capitatus, Udotea flabellum, and Halimeda opuntia. They represent the only important sulfated polysaccharides present in the cell walls of these highly calcified seaweeds of the suborder Halimedineae. Their structural features were studied by chemical analyses and NMR spectroscopy. Their backbone comprises 3-, 6-, and 3,6-linkages, constituted by major amounts of 3-linked 4,6-O-(1'-carboxy)ethylidene-d-galactopyranose units in part sulfated on C-2. Sulfation on C-2 was not found in galactans from other seaweeds of this order. In addition, a complex sulfation pattern, comprising also 4-, 6-, and 4,6-disulfated galactose units was found. A fraction from P. capitatus, F1, showed a moderate anticoagulant activity, evaluated by general coagulation tests and also kinetics of fibrin formation was assayed. Besides, preliminary results suggest that one of the possible mechanisms involved is direct thrombin inhibition. PMID:25817682

  14. Structural Analysis and Anticoagulant Activities of the Novel Sulfated Fucan Possessing a Regular Well-Defined Repeating Unit from Sea Cucumber

    Directory of Open Access Journals (Sweden)

    Mingyi Wu

    2015-04-01

    Full Text Available Sulfated fucans, the complex polysaccharides, exhibit various biological activities. Herein, we purified two fucans from the sea cucumbers Holothuria edulis and Ludwigothurea grisea. Their structures were verified by means of HPGPC, FT-IR, GC–MS and NMR. As a result, a novel structural motif for this type of polymers is reported. The fucans have a unique structure composed of a central core of regular (1→2 and (1→3-linked tetrasaccharide repeating units. Approximately 50% of the units from L. grisea (100% for H. edulis fucan contain sides of oligosaccharides formed by nonsulfated fucose units linked to the O-4 position of the central core. Anticoagulant activity assays indicate that the sea cucumber fucans strongly inhibit human blood clotting through the intrinsic pathways of the coagulation cascade. Moreover, the mechanism of anticoagulant action of the fucans is selective inhibition of thrombin activity by heparin cofactor II. The distinctive tetrasaccharide repeating units contribute to the anticoagulant action. Additionally, unlike the fucans from marine alga, although the sea cucumber fucans have great molecular weights and affluent sulfates, they do not induce platelet aggregation. Overall, our results may be helpful in understanding the structure-function relationships of the well-defined polysaccharides from invertebrate as new types of safer anticoagulants.

  15. Pharmacologic Therapies in Anticoagulation.

    Science.gov (United States)

    Ferreira, Joana Lima; Wipf, Joyce E

    2016-07-01

    Anticoagulants are beneficial for prevention and treatment of venous thromboembolism and stroke prevention in atrial fibrillation. The development of target-specific oral anticoagulants is changing the landscape of anticoagulation therapy and created growing interest on this subject. Understanding the pharmacology of different anticoagulants is the first step to adequately treat patients with best available therapy while avoiding serious bleeding complications. This article reviews the pharmacology of the main anticoagulant classes (vitamin K antagonists, direct oral anticoagulants, and heparins) and their clinical indications based on evidence-based data currently available in the literature. PMID:27235611

  16. Recombinant activated protein C attenuates coagulopathy and inflammation when administered early in murine pneumococcal pneumonia

    NARCIS (Netherlands)

    M. Schouten; C. van 't Veer; J.J.T.H. Roelofs; B. Gerlitz; B.W. Grinnell; M. Levi; T. van der Poll

    2011-01-01

    Recombinant human activated protein C (APC), which has both anticoagulant and anti-inflammatory properties, improves survival of patients with severe sepsis. This beneficial effect is especially apparent in patients with pneumococcal pneumonia. Earlier treatment with APC in sepsis has been associate

  17. Screening of the components with blood-anticoagulant activity from marine algae Sargassum fusiforme and Undaria pinnatifida%羊栖菜和裙带菜中抗凝血活性物质的初步筛选

    Institute of Scientific and Technical Information of China (English)

    刘承初; 周颖; 邬英睿; 甘建红; 周培根

    2004-01-01

    Components with blood-anticoagulant activity were fractionated from marine algae Sargassumfusiforrne and Undaria pinnatifida and the activity of the components was investigated by using the method of bioassay. It was found that the 80% ethanol soluble fraction of Sargassumfusiforme exhibited no blood-anticoagulant activity, while the components obtained from the 80 % ethanol insoluble fraction (hot water extract) gave obvious bloodanticoagulant activity. A further study suggests that the principal component in the hot water extract from Sargassumfusiforrne with high blood-anticoagulant activity should be sulfated polysaccharides, in which the activity was positively correlated with the content of total sugar and fucose in sulfated polysaccharides. As for Undaria pinnatifida, the n-butanol extract fractionated from the 80% ethanol soluble fraction had blood anticoagulant activity, while the petroleum ether, ether, ethyl acetate, or water extract showed no bloodanticoagulant activity.

  18. Venous Thromboembolism Anticoagulation Therapy

    Institute of Scientific and Technical Information of China (English)

    刘泽霖

    2009-01-01

    @@ VTE of the main treatment for anticoagulant thera-py, anticoagulant therapy drug of choice for low molecu-lar weight heparin (LMWH) for the overwhelming major-ity of clinicians agree that long-term oral anticoagulant therapy is still Vit. K antagonist (mainly warfarin).

  19. Recombinant human activated protein C inhibits local and systemic activation of coagulation without influencing inflammation during Pseudomonas aeruginosa pneumonia in rats

    NARCIS (Netherlands)

    Choi, Goda; Hofstra, Jorrit-Jan H; Roelofs, Joris J T H; Florquin, Sandrine; Bresser, Paul; Levi, Marcel; van der Poll, Tom; Schultz, Marcus J

    2007-01-01

    OBJECTIVE: Alveolar fibrin deposition is a hallmark of pneumonia. It has been proposed that recombinant human activated protein C exerts lung-protective effects via anticoagulant and anti-inflammatory pathways. We investigated the role of the protein C system in pneumonia caused by Pseudomonas aerug

  20. Isolamento, fracionamento e atividade anticoagulante de iota-carragenanas da Solieria filiformis Isolation, fractionation and anticoagulant activity of iota-carrageenans from Solieria filiformis

    Directory of Open Access Journals (Sweden)

    José Ariévilo Gurgel Rodrigues

    2010-11-01

    Full Text Available Este estudo teve como objetivo isolar, fracionar e avaliar o potencial anticoagulante de iota-carragenanas (i-CARs da rodofícea Solieria filiformis, quando obtidas por dois métodos de extração (M I e M II. As i-CARs foram isoladas com papaína bruta em tampão acetato de sódio 0,1M (pH 5,0, contendo cisteína 5mM e EDTA 5mM (M I ou água (80°C (M II e, em seguida, determinada sua composição química de carboidratos totais, sulfato livre (SL e proteínas contaminantes. As i-CARs foram submetidas à cromatografia de troca iônica (DEAE-celulose usando um gradiente de cloreto de sódio, sendo avaliado o tempo de tromboplastina parcial ativada (TTPA e tempo de protrombina das frações obtidas e comparadas à heparina (193UI mg-1. Uma fração anticoagulante também foi submetida ao procedimento de eletroforese em gel de agarose a 0,5%. A diferença no rendimento de i-CARs entre os métodos foi 10,14%. A composição química de SL (29,40% e o fracionamento, por DEAE-celulose, indicaram o M I mais eficiente na obtenção de i-CARs, comparado ao M II. O TTPA também foi somente alterado para as i-CARs do M I. Contudo, a atividade anticoagulante in vitro de uma fração rica (8,52UI mg-1 foi inferior à da heparina.This study aimed to isolate, fractionate and evaluate the anticoagulant potential of iota-carrageenans (i-CARs from Solieria filiformis when two extraction methods (M I and M II were used. i-CARs were isolated with papain in 0.1M sodium acetate (pH 5.0 containing 5mM cystein and 5mM EDTA (M I or water (80°C (M II, and then their chemical composition of total carbohydrates, free sulfate (FS and contaminant proteins were determined. i-CARs were submitted to anion-exchange chromatography (DEAE-cellulose using a sodium chloride gradient,being evaluated the activated partial thromboplastin time (APTT and prothrombin time of obtained fractions and compared to heparin (193IU mg-1. A rich fraction of anticoagulant was also submitted to 0

  1. Increased anticoagulant activity of thrombin-binding DNA aptamers by nanoscale organization on DNA nanostructures

    DEFF Research Database (Denmark)

    Rangnekar, Abhijit; Zhang, Alex M.; Shiyuan Li, Susan;

    2012-01-01

    Control over thrombin activity is much desired to regulate blood clotting in surgical and therapeutic situations. Thrombin-binding RNA and DNA aptamers have been used to inhibit thrombin activity and thus the coagulation cascade. Soluble DNA aptamers, as well as two different aptamers tethered by...

  2. Placental dermatan sulfate: isolation, anticoagulant activity, and association with heparin cofactor II

    OpenAIRE

    Giri, Tusar K.; Tollefsen, Douglas M.

    2006-01-01

    Pregnancy is associated with hemostatic challenges that may lead to thrombosis. Heparin cofactor II (HCII) is a glycosaminoglycan-dependent thrombin inhibitor present in both maternal and fetal plasma. HCII activity increases during pregnancy, and HCII levels are significantly decreased in women with severe pre-eclampsia. Dermatan sulfate (DS) specifically activates HCII and is abundant in the placenta, but the locations of DS and HCII in the placenta have not been determined. We present evid...

  3. Crystallization and Preliminary X-ray Diffraction Analysis of Hemextin A: A Unique Anticoagulant Protein from Hemachatus haemachatus Venom

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee,Y.; Kumar, S.; Jobichen, C.; Kini, R.

    2007-01-01

    Hemextin A was isolated and purified from African Ringhals cobra (Hemachatus haemachatus). It is a three-finger toxin that specifically inhibits blood coagulation factor VIIa and clot formation and that also interacts with hemextin B to form a unique anticoagulant complex. Hemextin A was crystallized by the hanging-drop vapor-diffusion method by equilibration against 0.2 M ammonium acetate, 0.1 M sodium acetate trihydrate pH 4.6 and 30% PEG 4000 as the precipitating agent. The crystals belong to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 49.27, b = 49.51, c = 57.87 {angstrom} and two molecules in the asymmetric unit. They diffracted to 1.5 {angstrom} resolution at beamline X25 at BNL.

  4. Acute coagulopathy of trauma: balancing progressive catecholamine induced endothelial activation and damage by fluid phase anticoagulation

    DEFF Research Database (Denmark)

    Johansson, P I; Ostrowski, S R

    2010-01-01

    Acute coagulopathy of trauma predicts a poor clinical outcome. Tissue trauma activates the sympathoadrenal system resulting in high circulating levels of catecholamines that influence hemostasis dose-dependently through immediate effects on the two major compartments of hemostasis, i.e., the...... circulating blood and the vascular endothelium. There appears to be a dose-dependency with regards to injury severity and the hemostatic response to trauma evaluated in whole blood by viscoelastic assays like thrombelastography (TEG), changing from normal to hypercoagulable, to hypocoagulable and finally...... evolutionary developed response that counterbalances the injury and catecholamine induced endothelial activation and damage. Given this, the rise in circulating catecholamines in trauma patients may favor a switch from hyper- to hypocoagulability in the blood to keep the progressively more procoagulant...

  5. Heterofucans from the Brown Seaweed Canistrocarpus cervicornis with Anticoagulant and Antioxidant Activities

    OpenAIRE

    Hugo Alexandre de Oliveira Rocha; Sara Lima Cordeiro; Mariana Santana Santos Pereira Costa; Luciana Guimaraes Alves; Nednaldo Dantas-Santos; Gabriel Pereira Fidelis; Leonardo Thiago Duarte Barreto Nobre; Rafael Barros Gomes Camara; Leandro Silva Costa

    2011-01-01

    Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated L-fucose. We extracted six fucans from Canistrocarpus cervicornis by proteolytic digestion followed by sequential acetone precipitation. These heterofucans are composed mainly of fucose, glucuronic acid, galactose and sulfate. No polysaccharide was capable of prolonging prothrombin time (PT) at the concentration assayed. However, all polysaccharides prolonged activated partial thromboplastin time (aPTT). ...

  6. [Effect on low-molecular-weight heparin obtained using a chitinolytic complex on the anticoagulant activity of plasma in rabbits and rats].

    Science.gov (United States)

    Drozd, N N; Tolstenkov, A S; Makarov, V A; Miftakhova, N T; Bannikova, G E; Sukhanova, P P; Varlamov, V P; Vikhoreva, G E

    2007-01-01

    The anticoagulant activity of low-molecular-weight heparin with an average molecular weight of 4.7 kD (LMWH-4.7) has been studied. This derivative was prepared from unfractionated heparin with the help of chitinolytic enzyme complex from Streptomyces kurssanovii. The antithrombin activity of LMWH-4.7 (aIla activity) was 72 +/- 9 IU/mg and the activity with respect to the blood coagulation factor Xa (aXa activity) was 200 +/- 33 IU/mg, which corresponded to an aXa/aIIa ratio of 2.8 (necessary for effective antithrombotic drugs). The aIIa and aXa activity exhibited a dose-dependent variation upon intravenous and subcutaneous injections in rabbits, so that a high aIIa/aXa ratio was retained: 5 min after the intravenous injection of a minimum dose (0.3 mg/kg), this ratio was 2, 7, and for a greater dose (3.0 mg/kg) it reached 3.8. Subcutaneous injections were followed by slow elimination of the anticoagulant within 24 h. LMWH-4.7 upon intraperitoneal injections produced a dose-dependent inhibition of a model thrombosis in rats. Complete inhibition was observed for a dose of 3 mg/kg. Thus, it is possible to obtain active LMW heparin with the help of chitinases. PMID:17523450

  7. Optical profiling of anticoagulation status (Conference Presentation)

    Science.gov (United States)

    Tshikudi, Diane M.; Tripathi, Markandey M.; Hajjarian, Zeinab; Nadkarni, Seemantini K.

    2016-02-01

    Defective blood coagulation resulting from excessive procoagulant activity often leads to thrombotic disorders such as stroke and myocardial infarction. A variety of oral and injectable anticoagulant drugs are prescribed to prevent or treat life-threatening thrombosis. However, due to bleeding complications often associated with anticoagulant treatment, routine monitoring and accurate dosing of anticoagulant therapy is imperative. We have developed Optical thromboelastography (OTEG), a non-contact approach that utilizes a drop of whole blood to measure blood coagulation status in patients. Here, we demonstrate the capability of OTEG for rapidly monitoring anticoagulation in whole blood samples. OTEG monitors coagulation status by assessing changes in blood viscosity from temporal intensity fluctuations of laser speckle patterns during clotting. In OTEG a blood drop is illuminated with coherent light and the blood viscosity is measured from the speckle intensity autocorrelation curve, g2 (t). The metrics, clotting time (R+k), clot progression (angle) and maximum clot stiffness (MA) are then extracted. The aim of the current study was to evaluate the accuracy of OTEG in assessing anticoagulation status of common anticoagulants including heparin, argatroban and rivaroxaban status. A dose-dependent prolongation of R+k was observed in anticoagulated blood, which closely corresponded with standard-reference Thromboelastography (TEG) (r 0.87-0.99, P>0.01 for all cases). OTEG angle was unaltered by anticoagulation whereas TEG angle presented a dose-dependent diminution probably linked to clot rupture. In both OTEG and TEG, MA was unaffected by heparin, argatroban or rivaroxaban. We conclude that OTEG can accurately monitor anticoagulation status following treatment, potentially providing a powerful tool for routine monitoring of patients in the doctor's office or in the home setting.

  8. Anticoagulation control in atrial fibrillation patients present to outpatient clinic of cardiology versus anticoagulant clinics

    Institute of Scientific and Technical Information of China (English)

    DU Xin; MA Chang-sheng; LIU Xiao-hui; DONG Jian-zeng; WANG Jun-nan; CHENG Xiao-jing

    2005-01-01

    @@ Nonvalvular atrial fibrillation (NVAF) is the most common sustained cardiac arrhythmia in clinical practice, which if untreated results in a doubling of cardiovascular morbidity and mortality. AF is an independent predictor of stroke, with an annual risk 5 to 6 times higher than patients in sinus rhythm.1 During recent years, several randomised clinical trials conducted by investigators around the world involving 13 843 participants with NVAF have demonstrated convincingly the value of warfarin therapies for stroke prevention in high risk patients.2-8 However, the dose response of warfarin is complex and its activity is easily altered by concurrent medications, food interactions, alcohol and illnesses. Adherence to medical advice and routine monitoring of the international normalized ratio (INR) is important, because low anticoagulant intensity predisposes the patients to thromboembolic complications and high intensity to haemorrhage. Studies suggested that anticoagulant clinics could improve the quality of anticoagulation control,9 and anticoagulant clinics are common in western countries. However, in China, most AF patients taking warfarin usually attend the outpatient clinic of cardiology, while the quality of anticoagulation control is never investigated. We therefore assessed anticoagulation control in the outpatient clinic of cardiology, and the quality of anticoagulation control since the establishment of anticoagulant clinics.

  9. Erythrocyte-derived microparticles supporting activated protein C-mediated regulation of blood coagulation.

    Directory of Open Access Journals (Sweden)

    Ruzica Livaja Koshiar

    Full Text Available Elevated levels of erythrocyte-derived microparticles are present in the circulation in medical conditions affecting the red blood cells. Erythrocyte-derived microparticles expose phosphatidylserine thus providing a suitable surface for procoagulant reactions leading to thrombin formation via the tenase and prothrombinase complexes. Patients with elevated levels of circulating erythrocyte-derived microparticles have increased thrombin generation in vivo. The aim of the present study was to investigate whether erythrocyte-derived microparticles are able to support the anticoagulant reactions of the protein C system. Erythrocyte-derived microparticles were isolated using ultracentrifugation after incubation of freshly prepared erythrocytes with the ionophore A23187 or from outdated erythrocyte concentrates, the different microparticles preparations yielding similar results. According to flow cytometry analysis, the microparticles exposed phoshatidylserine and bound lactadherin, annexin V, and protein S, which is a cofactor to activated protein C. The microparticles were able to assemble the tenase and prothrombinase complexes and to stimulate the formation of thrombin in plasma-based thrombin generation assay both in presence and absence of added tissue factor. The addition of activated protein C in the thrombin generation assay inhibited thrombin generation in a dose-dependent fashion. The anticoagulant effect of activated protein C in the thrombin generation assay was inhibited by a monoclonal antibody that prevents binding of protein S to microparticles and also attenuated by anti-TFPI antibodies. In the presence of erythrocyte-derived microparticles, activated protein C inhibited tenase and prothrombinase by degrading the cofactors FVIIIa and FVa, respectively. Protein S stimulated the Arg306-cleavage in FVa, whereas efficient inhibition of FVIIIa depended on the synergistic cofactor activity of protein S and FV. In summary, the erythrocyte

  10. In Vivo Anticoagulant and Thrombolytic Activities of a Fibrinolytic Serine Protease (Brevithrombolase) With the k-Carrageenan-Induced Rat Tail Thrombosis Model.

    Science.gov (United States)

    Majumdar, Sourav; Chattopadhyay, Pronobesh; Mukherjee, Ashis K

    2016-09-01

    In the present study, in vivo thrombolysis efficiency of Brevithrombolase, a nontoxic fibrinolytic enzyme purified from Brevibacillus brevis strain FF02B, was affirmed by significant inhibition of thrombus formation in the k-carrageenan-induced rat tail, in a dose-dependent manner. Brevithrombolase at a dose of 600 µg/kg showed an efficacy that was comparable to streptokinase and plasmin, in dissolving in vivo thrombus of k-carrageenan-treated rats under identical conditions. The in vivo anticoagulant property of Brevithrombolase was demonstrated by its prolongation of activated partial thromboplastin time, prothrombin time, and thrombin time in Wistar rats. However, the Brevithrombolase-treated rats demonstrated an insignificant decrease in fibrinogen (Fg) level of plasma compared with Fg level of control group of rats corroborating in vivo as well as in vitro anticoagulant activity of Brevithrombolase is due to its hydrolytic action on thrombin. These findings unequivocally suggest that Brevithrombolase may serve a promising alternative to the commercial thrombolytic drugs. PMID:25657326

  11. Secretion of a proteolytic anticoagulant by Ancylostoma hookworms

    OpenAIRE

    1983-01-01

    Hookworms of the genus Ancylostoma secrete an anticoagulant that both inhibits the clotting of human plasma and promotes fibrin clot dissolution. This anticoagulant activity is attributable to a 36,000 dalton proteolytic enzyme. The protease can degrade fibrinogen into five smaller polypeptides that intrinsically have anticoagulating properties, covert plasminogen to a mini-plasminogen-like molecule, and hydrolyze a synthetic peptide substrate with specificity for elastolytic enzymes. It is h...

  12. Detailed Mechanisms of the Inactivation of Factor VIIIa by Activated Protein C in the Presence of Its Cofactors, Protein S and Factor V*

    OpenAIRE

    Gale, Andrew J.; Cramer, Thomas J.; Rozenshteyn, Diana; Cruz, Jason R.

    2008-01-01

    Factor VIIIa is inactivated by a combination of two mechanisms. Activation of factor VIII by thrombin results in a heterotrimeric factor VIIIa that spontaneously inactivates due to dissociation of the A2 subunit. Additionally, factor VIIIa is cleaved by the anticoagulant serine protease, activated protein C, at two cleavage sites, Arg336 in the A1 subunit and Arg562 in the A2 subunit. We previously characterized an engineered variant of factor VIII which contains a dis...

  13. Lupus anticoagulants and antiphospholipid antibodies

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000547.htm Lupus anticoagulants and antiphospholipid antibodies To use the sharing features on this page, please enable JavaScript. Lupus anticoagulants are antibodies against substances in the lining ...

  14. Anticoagulant activity of sulfated polysaccharides fractions from an aqueous extract obtained from the red seaweed Halymenia floresia (Clemente C. Agardh - doi: 10.4025/actascitechnol.v33i4.9143

    Directory of Open Access Journals (Sweden)

    José Ariévilo Gurgel Rodrigues

    2011-09-01

    Full Text Available Heparin (HEP is known due to their side effects and the red seaweed Halymenia floresia (Hf sulfated polysaccharides (SP are heparinoids. In this study we purified the Hf-SP obtained from an aqueous extract and evaluated their anticoagulant activities. Hf-SP1 (25°C, Hf-SP2 (80°C and Hf-SP3 (80°C were sequentially isolated. Hf-SP3 had the highest sulfate content (37.45%. Hf-SP3 was fractionated by ion exchange chromatography on a DEAE-cellulose column using a NaCl gradient. Fractions were lyophilized and submitted to 0.5% agarose gel electrophoresis. The anticoagulant activity was evaluated by the activated partial thromboplastin time using rabbits plasma and expressed in international units per mg of SP using standard HEP (193 IU mg-1. The chromatographic procedure separated into four different SP fractions (F I, F II, F III and F IV eluted at concentrations of 0.50, 0.75, 1.00 and 1.25 M of NaCl, respectively, reveling among them different marked on charge density, when compared by electrophoresis. F III had the highest anticoagulant activity (10.72 IU mg-1, suggesting that the sulfate is important in this process. In conclusion, our results suggest that sequential extractions of Hf-SP are an important biotechnological tool for identification of novel anticoagulants and studies of structural characterization are already in progress.

  15. Anticoagulants in pregnancy.

    Science.gov (United States)

    Howie, P W

    1986-06-01

    Thromboembolic disorders are still a serious problem in pregnancy and anticoagulants have an important part to play in both treatment and prevention. Warfarin is the most convenient drug to give but can cause maternal and fetal bleeding problems, especially during late pregnancy and delivery. There are also small risks of embryopathy from warfarin in early pregnancy but these may have been overstated. Heparin, which has to be given parenterally, does not cross the placental barrier but can still cause bleeding problems in pregnancy. Full intravenous heparin is only suitable for short-term use, and subcutaneous heparin has been introduced for long-term therapy. This regimen is a useful advance but long-term use still has problems of bruising and maternal bone demineralization. The standard treatment of acute thromboembolic events in pregnancy is continuous intravenous heparin followed by either subcutaneous heparin or warfarin, the latter being changed at 36 weeks gestation. In the prophylaxis of thromboembolism, the trend is towards a more selective approach, anticoagulants being given during pregnancy to those at highest risk and during labour and the puerperium to all with a previous history of thromboembolism. Anticoagulants during pregnancy are necessary in patients with artificial heart valves and, because subcutaneous heparin is not sufficient, warfarin should be used until 36 weeks followed by continuous intravenous heparin until delivery. No method of anticoagulation during pregnancy is entirely free of risk and all management policies must be based on an estimate of risk-benefit ratio in individual patients. PMID:2426029

  16. Cataract surgery and anticoagulants

    NARCIS (Netherlands)

    Koopmans, SA; VanRij, G

    1996-01-01

    A questionnaire was sent to 240 members of the Netherlands Intraocular implant Club (NIOIC) to register their policy followed in 1993 with regard to anticoagulant therapy (ACT) and the use of aspirin in patients having cataract surgery. Ninety-one (32%) forms were suitable for analysis. Most eye sur

  17. Anticoagulation in atrial fibrillation.

    Science.gov (United States)

    Steinberg, Benjamin A; Piccini, Jonathan P

    2014-01-01

    Atrial fibrillation increases the risk of stroke, which is a leading cause of death and disability worldwide. The use of oral anticoagulation in patients with atrial fibrillation at moderate or high risk of stroke, estimated by established criteria, improves outcomes. However, to ensure that the benefits exceed the risks of bleeding, appropriate patient selection is essential. Vitamin K antagonism has been the mainstay of treatment; however, newer drugs with novel mechanisms are also available. These novel oral anticoagulants (direct thrombin inhibitors and factor Xa inhibitors) obviate many of warfarin's shortcomings, and they have demonstrated safety and efficacy in large randomized trials of patients with non-valvular atrial fibrillation. However, the management of patients taking warfarin or novel agents remains a clinical challenge. There are several important considerations when selecting anticoagulant therapy for patients with atrial fibrillation. This review will discuss the rationale for anticoagulation in patients with atrial fibrillation; risk stratification for treatment; available agents; the appropriate implementation of these agents; and additional, specific clinical considerations for treatment. PMID:24733535

  18. Neuroprotective effects of activated protein C on intrauterine inflammation-induced neonatal white matter injury are associated with the downregulation of fibrinogen-like protein 2/fibroleukin prothrombinase and the inhibition of pro-inflammatory cytokine expression

    OpenAIRE

    JIN, SHENG-JUAN; Yan LIU; DENG, SHI-HUA; LIAO, LI-HONG; LIN, TU-LIAN; Ning, Qin; LUO, XIAO-PING

    2015-01-01

    Maternal intrauterine inflammation or infection is an important risk factor for neonatal cerebral white matter injury (WMI) and future neurological deficits. Activated protein C (APC), a natural anticoagulant, has been shown to exhibit anti-inflammatory, anti-apoptotic, profibrinolytic and cytoprotective activities. Recent studies have demonstrated that the novel prothrombinase, fibrinogen-like protein 2 (fgl2), contributes to the pathogenesis of a number of inflammatory diseases through the ...

  19. Anticoagulation in Atrial Fibrillation

    OpenAIRE

    Ahmad, Yousif; YH Lip, Gregory

    2012-01-01

    Patients with atrial fibrillation (AF) are at increased thromboembolic risk, and they suffer more severe strokes with worse outcomes. Most thromboembolic complications of AF are eminently preventable with oral anticoagulation, and the increasing numbers of AF patients mean antithrombotic therapy is the most crucial management aspect of this common arrhythmia. Despite the proven efficacy of warfarin, a string of limitations have meant that it is underused by physicians and patients alike. This...

  20. Anticoagulation in atrial fibrillation

    OpenAIRE

    Steinberg, Benjamin A; Piccini, Jonathan P.

    2014-01-01

    Atrial fibrillation increases the risk of stroke, which is a leading cause of death and disability worldwide. The use of oral anticoagulation in patients with atrial fibrillation at moderate or high risk of stroke, estimated by established criteria, improves outcomes. However, to ensure that the benefits exceed the risks of bleeding, appropriate patient selection is essential. Vitamin K antagonism has been the mainstay of treatment; however, newer drugs with novel mechanisms are also availabl...

  1. Activated protein C: A regulator of human skin epidermal keratinocyte function

    Institute of Scientific and Technical Information of China (English)

    Kelly; McKelvey; Christopher; John; Jackson; Meilang; Xue

    2014-01-01

    Activated protein C(APC) is a physiological anticoagulant, derived from its precursor protein C(PC). Independent of its anticoagulation, APC possesses strong anti-inflammatory, anti-apoptotic and barrier protective properties which appear to be protective in a number of disorders including chronic wound healing. The epidermis is the outermost skin layer and provides the first line of defence against the external environment. Keratinocytes are the most predominant cells in the epidermis and play a critical role in maintaining epidermal barrier function. PC/APC and its receptor, endothelial protein C receptor(EPCR), once thought to be restricted to the endothelium, are abundantly expressed by skin epidermal keratinocytes. These cells respond to APC by upregulating proliferation, migration and matrix metalloproteinase-2 activity and inhibiting apoptosis/inflammation leading to a wound healing phenotype. APC also increases barrier function of keratinocyte monolayers by promoting the expression of tight junction proteins and re-distributing them to cell-cell contacts. These cytoprotective properties of APC are mediated through EPCR, protease-activated receptors, epidermal growth factor receptor or Tie2. Future preventive and therapeutic uses of APC in skin disorders associated with disruption of barrier function and inflammation look promising. This review will focus on APC’s function in skin epidermis/keratinocytes and its therapeutical potential in skin inflammatory conditions.

  2. Synthetic oligosaccharides as heparin-mimetics displaying anticoagulant properties.

    Science.gov (United States)

    Avci, Fikri Y; Karst, Nathalie A; Linhardt, Robert J

    2003-01-01

    Heparin and low molecular weight heparins are major clinical anticoagulants and the drugs of choice for the treatment of deep venous thrombosis. The discovery of an antithrombin binding domain in heparin focused interest on understanding the mechanism of heparin's antithrombotic/ anticoagulant activity. Various heparin-mimetic oligosaccharides have been prepared in an effort to replace polydisperse heparin and low molecular weight heparins with a structurally-defined anticoagulant. The goal of attaining a heparin-mimetic with no unwanted side-effects has also provided motivation for these efforts. This article reviews structure-activity relationship (SAR) of structurally-defined heparin-mimetic oligosaccharides. PMID:14529394

  3. Pharmacokinetics of activated protein C in guinea pigs

    International Nuclear Information System (INIS)

    Protein C is a vitamin K-dependent zymogen of the serine protease, activated protein C (APC), an important regulatory enzyme in hemostasis. In view of the potential of human APC as an anticoagulant and profibrinolytic agent, the pharmacokinetics and tissue distribution of APC were studied in guinea pigs. The plasma elimination of a trace dose of 125I-APC was biphasic following an initial rapid elimination of approximately 15% of the injected dose within 1 to 2 minutes. This rapid removal of 125I-APC from the circulation was found to be a result of an association with the liver regardless of the route of injection. Essentially identical results were obtained with active site-blocked forms of APC generated with either diisopropylfluorophosphate or D-phenylalanyl-L-prolyl-L-arginine chloromethyl ketone, which indicates that the active site was not essential for the liver association. Accumulation of all three forms of APC in the liver peaked at 30 minutes and then declined as increasing amounts of degraded radiolabeled material appeared in the gastrointestinal tract and urine. Removal of the gamma-carboxyglutamic acid (gla) domain of diisopropylphosphoryl-APC resulted in a 50% reduction in the association with liver and an accumulation in the kidneys. Protein C and protein S were cleared from the circulation at rates approximately one-half and one-fourth, respectively, that of APC. Both in vitro and in vivo, APC was found to form complexes with protease inhibitors present in guinea pig plasma. Complex formation resulted in a more rapid disappearance of the enzymatic activity of APC than elimination of the protein moiety. These findings indicate two distinct mechanisms for the elimination of APC. One mechanism involves reaction with plasma protease inhibitors and subsequent elimination by specific hepatic receptors. (Abstract Truncated)

  4. [Direct oral anticoagulant associated bleeding].

    Science.gov (United States)

    Godier, A; Martin, A-C; Rosencher, N; Susen, S

    2016-07-01

    Direct oral anticoagulants (DOAC) are recommended for stroke prevention in atrial fibrillation and for the treatment of venous thromboembolism. However, they are associated with hemorrhagic complications. Management of DOAC-induced bleeding remains challenging. Activated or non-activated prothrombin concentrates are proposed, although their efficacy to reverse DOAC is uncertain. Therapeutic options also include antidotes: idarucizumab, antidote for dabigatran, has been approved for use whereas andexanet alpha, antidote for anti-Xa agents, and aripazine, antidote for all DOAC, are under development. Other options include hemodialysis for the treatment of dabigatran-associated bleeding and administration of oral charcoal if recent DOAC ingestion. DOAC plasma concentration measurement is necessary to guide DOAC reversal. We propose an update on DOAC-associated bleeding, integrating the availability of dabigatran antidote and the critical place of DOAC concentration measurements. PMID:27297642

  5. Extraction and anticoagulant activity of sulfated polysaccharides from Caulerpa cupressoides var. lycopodium (Vahl C. Agardh (Chlorophyceae - doi: 10.4025/actascibiolsci.v33i2.6243 Extraction and anticoagulant activity of sulfated polysaccharides from Caulerpa cupressoides var. lycopodium (Vahl C. Agardh (Chlorophyceae - doi: 10.4025/actascibiolsci.v33i2.6243

    Directory of Open Access Journals (Sweden)

    Norma Maria Barros Benevides

    2011-05-01

    Full Text Available The reportedly low standard quality of heparin (HEP for use in cardiac surgeries has led to concern in the Brazilian and international markets. Sulfated polysaccharides (SPs from seaweeds have been regarded as promising substitutes for HEP. The aim of this study was to sequentially extract total SPs (TSPs from Caulerpa cupressoides (Chlorophyceae with papain in 100 mM sodium acetate buffer (pH 5.0 containing 5 mM cysteine and 5 mM EDTA, followed by fractionation by ion-exchange chromatography (DEAE-cellulose, and then evaluate the anticoagulant potential of SP fractions by activated partial thromboplastin time (APTT using normal human plasma and compare it to standard HEP (193 IU mg-1. The obtained fractions were chemically characterized by chemical composition and agarose gel electrophoresis. The yield was 4.61%, and three fractions of SP (F I, F II and F III eluted with 0.50, 0.75 and 1.00 M of NaCl, respectively, were observed on chromatography profiles; however, differences in charge densities patterns and degree of resolution among them were revealed by electrophoresis. SPs were capable of modifying APTT only in fractions eluted with 0.75 M of NaCl, whose activities were 23.37 and 25.76 IU mg-1, respectively, and the charge density was prerequisite to activity. Therefore, C. cupressoides is a source of SPs possessing low anticoagulant potential compared to HEP.The reportedly low standard quality of heparin (HEP for use in cardiac surgeries has led to concern in the Brazilian and international markets. Sulfated polysaccharides (SPs from seaweeds have been regarded as promising substitutes for HEP. The aim of this study was to sequentially extract total SPs (TSPs from Caulerpa cupressoides (Chlorophyceae with papain in 100 mM sodium acetate buffer (pH 5.0 containing 5 mM cysteine and 5 mM EDTA, followed by fractionation by ion-exchange chromatography (DEAE-cellulose, and then evaluate the anticoagulant potential of SP fractions by activated

  6. Marine pharmacology in 2003-4: Marine Compounds with Anthelminthic, Antibacterial, Anticoagulant, Antifungal, Anti-inflammatory, Antimalarial, Antiplatelet, Antiprotozoal, Antituberculosis, and Antiviral Activities; affecting the Cardiovascular, Immune and Nervous Systems, and other Miscellaneous Mechanisms of Action

    OpenAIRE

    Mayer, Alejandro M. S.; Rodriguez, Abimael D.; Berlinck, Roberto G. S.; Hamann, Mark T.

    2007-01-01

    The current marine pharmacology review that covers the peer-reviewed literature during 2003 and 2004 is a sequel to the authors' 1998-2002 reviews, and highlights the preclinical pharmacology of 166 marine chemicals derived from a diverse group of marine animals, algae, fungi and bacteria. Anthelminthic, antibacterial, anticoagulant, antifungal, antimalarial, antiplatelet, antiprotozoal, antituberculosis or antiviral activities were reported for 67 marine chemicals. Additionally 45 marine com...

  7. Procoagulants and anticoagulants in fetal blood. A literature survey.

    Directory of Open Access Journals (Sweden)

    Waldemar Uszyński

    2010-05-01

    Full Text Available In intrauterine life, hemostasis is maintained by the same components as in extrauterine life (blood platelets, coagulation and fibrinolysis systems, involvement of the vascular wall; in the fetus, however, these components show significant differences of a quantitative/qualitative nature. In the present study, we surveyed the literature on the coagulation system in the fetus. We focused on the velocity of development of the coagulation system, being reflected in the increased concentration of all procoagulants and anticoagulants (a rise from approximately 20% in the middle of pregnancy to about 60% or more in the period of labor; exceptions: factors V, VIII and XIII which in the labor period reach the adult level and screening test results (prothrombin time, aPTT - activated prothrombin time, and thrombin time. Reference values were given for the 19-38 weeks of pregnancy and the labor term. Biochemical features of fetal fibrinogen and PIVKA factors were also discussed. The role of activated protein C (APC in the maintenance of balance between procoagulants and anticoagulants was postulated as well as the role of APC in the formation of thrombin activatable fibrinolysis inhibitor (TAFI.

  8. Clinical Safety of a High Dose of Phycocyanin-Enriched Aqueous Extract from Arthrospira (Spirulina) platensis: Results from a Randomized, Double-Blind, Placebo-Controlled Study with a Focus on Anticoagulant Activity and Platelet Activation.

    Science.gov (United States)

    Jensen, Gitte S; Drapeau, Cassandra; Lenninger, Miki; Benson, Kathleen F

    2016-07-01

    The goal for this study was to evaluate safety regarding anticoagulant activity and platelet activation during daily consumption of an aqueous cyanophyta extract (ACE), containing a high dose of phycocyanin. Using a randomized, double-blind, placebo-controlled study design, 24 men and women were enrolled after informed consent, and consumed either ACE (2.3 g/day) or placebo daily for 2 weeks. The ACE dose was equivalent to ∼1 g phycocyanin per day, chosen based on the highest dose Generally Recognized as Safe (GRAS) by the U.S. Food and Drug Administration. Consuming ACE did not alter markers for platelet activation (P-selectin expression) or serum P-selectin levels. No changes were seen for activated partial thromboplastin time, thrombin clotting time, or fibrinogen activity. Serum levels of aspartate transaminase (AST) showed a significant reduction after 2 weeks of ACE consumption (P < .001), in contrast to placebo where no changes were seen; the difference in AST levels between the two groups was significant at 2 weeks (P < .02). Reduced levels of alanine transaminase (ALT) were also seen in the group consuming ACE (P < .08). Previous studies showed reduction of chronic pain when consuming 1 g ACE per day. The higher dose of 2.3 g/day in this study was associated with significant reduction of chronic pain at rest and when physically active (P < .05). Consumption of ACE showed safety regarding markers pertaining to anticoagulant activity and platelet activation status, in conjunction with rapid and robust relief of chronic pain. Reduction in AST and ALT suggested improvement in liver function and metabolism. PMID:27362442

  9. Antiviral activities of whey proteins.

    Science.gov (United States)

    Ng, Tzi Bun; Cheung, Randy Chi Fai; Wong, Jack Ho; Wang, Yan; Ip, Denis Tsz Ming; Wan, David Chi Cheong; Xia, Jiang

    2015-09-01

    Milk contains an array of proteins with useful bioactivities. Many milk proteins encompassing native or chemically modified casein, lactoferrin, alpha-lactalbumin, and beta-lactoglobulin demonstrated antiviral activities. Casein and alpha-lactalbumin gained anti-HIV activity after modification with 3-hydroxyphthalic anhydride. Many milk proteins inhibited HIV reverse transcriptase. Bovine glycolactin, angiogenin-1, lactogenin, casein, alpha-lactalbumin, beta-lactoglobulin, bovine lactoferrampin, and human lactoferrampin inhibited HIV-1 protease and integrase. Several mammalian lactoferrins prevented hepatitis C infection. Lactoferrin, methylated alpha-lactalbumin and methylated beta-lactoglobulin inhibited human cytomegalovirus. Chemically modified alpha-lactalbumin, beta-lactoglobulin and lysozyme, lactoferrin and lactoferricin, methylated alpha-lactalbumin, methylated and ethylated beta-lactoglobulins inhibited HSV. Chemically modified bovine beta-lactoglobulin had antihuman papillomavirus activity. Beta-lactoglobulin, lactoferrin, esterified beta-lactoglobulin, and esterified lactoferrindisplayed anti-avian influenza A (H5N1) activity. Lactoferrin inhibited respiratory syncytial virus, hepatitis B virus, adenovirus, poliovirus, hantavirus, sindbis virus, semliki forest virus, echovirus, and enterovirus. Milk mucin, apolactoferrin, Fe(3+)-lactoferrin, beta-lactoglobulin, human lactadherin, bovine IgG, and bovine kappa-casein demonstrated antihuman rotavirus activity. PMID:26198883

  10. The practical management of bleedings during treatment with direct oral anticoagulants: the emergency reversal therapy

    Directory of Open Access Journals (Sweden)

    Luca Masotti

    2013-12-01

    Full Text Available Bleeding represents the most feared complication of the new oral anticoagulants, direct oral anticoagulants (DOACs, as well as all the antithrombotic therapies. During the acute phase of bleeding in patients taking anticoagulants, restoration of an effective hemostasis represents the cornerstone of practical management. While vitamin K antagonists are effectively and promptly reversed by specific antidotes such as prothrombin complex concentrates (PCCs, fresh frozen plasma or vitamin K, it is still not clear how to manage the urgent reversal of DOACs during life-threatening or major bleedings due to the lack of specific antidotes. However, in vitro and ex vivo studies have suggested some potential strategies to reverse DOACs in clinical practice, other than general support measures that are always recommended. Activated charcoal could be used in subjects with DOAC-related bleedings presenting to the emergency department within two hours of the last oral intake. Non-activated or activated PCCs (FEIBA and recombinant activated Factor VII (raFVII seem to be the optimal strategy for urgent reversal of dabigatran, while non-activated PCCs seem to have efficacy in reversing rivaroxaban. Due to its low plasma protein binding, dabigatran could be also dialyzed in urgent cases. Clinically relevant non-major bleedings and minor bleedings should be treated with general and local measures, respectively, and, when necessary, with dose delay or drug withdrawal. In this article, the Authors describe the practical approach to bleedings occurring during DOACs treatment.

  11. Comparing new anticoagulants.

    Science.gov (United States)

    Wooten, James M

    2012-12-01

    For years, the pharmaceutical industry has been trying to find a safe and effective drug to replace warfarin. Although warfarin is an effective anticoagulant, its pharmacology, adverse effects, and risk profiles dictate that patients taking this medication must be monitored judiciously. The US Food and Drug Administration has approved two drugs for commercial use, dabigatran and rivaroxaban, that will compete directly with warfarin for use in specific indications. Because of direct marketing to patients, physicians are being asked to comment on these new medications. This brief review illustrates the data available for the two new drugs when compared to warfarin for the specified indications. For some patients, these drugs may be highly beneficial and offer an excellent alternative to warfarin. For others, warfarin may still be the preferred drug. PMID:23211502

  12. Anticoagulant induced leukoagglutination

    International Nuclear Information System (INIS)

    Low leukocyte count secondary to leukocyte aggregation caused by an ethylene diamine tetra acetic acid (EDTA) occur in both benign and malignant disorders. We report a 71-year-old male patient who was admitted to the hospital with acute chest infection. Complete blood count (CBC) collected in ETDA tube and analyzed by sysmex instrument (SE/9500) revealed low hemoglobin level of 9.4g/dl, white blood cell (WBC) count of 8.2x109/L. Peripheral blood smear review shows multiple leukocyte aggregation (one clump in each field). When we asked for another blood sample in citrate anticoagulant, the CBC showed WBC count of 11.8x109/L and neutrophils of 6.26x109/L. This is a case of low leukocyte count secondary to leukocyte aggregation induced by EDTA. (author)

  13. Recurrent thrombotic occlusion of a transjugular intrahepatic portosystemic stent-shunt due to activated protein C resistance

    Institute of Scientific and Technical Information of China (English)

    Elmar Siewert; Jan Salzmann; Edmund Purucker; Karl Schürmann; Siegfried Matern

    2005-01-01

    The transjugular intrahepatic portosystemic stent-shunt (TIPS) has successfully been used in the management of refractory variceal bleeding and ascites in patients with portal hypertension. Major drawbacks are the induction of hepatic encephalopathy and shunt dysfunction. We present a 59-year-old woman with alcoholic liver cirrhosis who received a TIPS because of recurrent bleeding from esophageal varices. Stent occlusion occurred 4 mo after placement of the TIPS. Laboratory testing revealed resistance to activated protein C (APC). Combination therapy with low-dose enoxaparin and clopidogrel could not prevent her recurrent stent occlusion. Finally, therapy with high-dose enoxaparin was sufficient to prevent further shunt complications up to now (follow-up period of 1 year). In conclusion, early occlusion of a TIPS warrants testing for thrombophilia. If risk factors are confirmed,anticoagulation should be intensified. There are currently no evidence-based recommendations regarding the best available anticoagulant therapy and surveillance protocol for patients with TIPS.

  14. In vitro anti-inflammatory and anti-coagulant effects of antibiotics towards Platelet Activating Factor and thrombin

    OpenAIRE

    Demopoulos Constantinos A; Tsekes George; Lioni Athina; Tsogas Nickolaos; Chini Maria; Tsoupras Alexandros B; Lazanas Marios C

    2011-01-01

    Abstract Background Sepsis is characterized as a systemic inflammatory response that results from the inability of the immune system to limit bacterial spread during an ongoing infection. In this condition the significant mediator of inflammation Platelet Activating Factor (PAF) and the coagulant factor thrombin are implicated. In animal models, treatment with PAF-antagonists or co-administration of antibiotics with recombinant-PAF-Acetylhydrolase (rPAF-AH) have exhibited promising results. I...

  15. New Insights into the Pros and Cons of the Clinical Use of Vitamin K Antagonists (VKAs Versus Direct Oral Anticoagulants (DOACs

    Directory of Open Access Journals (Sweden)

    Rick H. van Gorp

    2015-11-01

    Full Text Available Vitamin K-antagonists (VKA are the most widely used anticoagulant drugs to treat patients at risk of arterial and venous thrombosis for the past 50 years. Due to unfavorable pharmacokinetics VKA have a small therapeutic window, require frequent monitoring, and are susceptible to drug and nutritional interactions. Additionally, the effect of VKA is not limited to coagulation, but affects all vitamin K-dependent proteins. As a consequence, VKA have detrimental side effects by enhancing medial and intimal calcification. These limitations stimulated the development of alternative anticoagulant drugs, resulting in direct oral anticoagulant (DOAC drugs, which specifically target coagulation factor Xa and thrombin. DOACs also display non-hemostatic vascular effects via protease-activated receptors (PARs. As atherosclerosis is characterized by a hypercoagulable state indicating the involvement of activated coagulation factors in the genesis of atherosclerosis, anticoagulation could have beneficial effects on atherosclerosis. Additionally, accumulating evidence demonstrates vascular benefit from high vitamin K intake. This review gives an update on oral anticoagulant treatment on the vasculature with a special focus on calcification and vitamin K interaction.

  16. New Insights into the Pros and Cons of the Clinical Use of Vitamin K Antagonists (VKAs) Versus Direct Oral Anticoagulants (DOACs).

    Science.gov (United States)

    van Gorp, Rick H; Schurgers, Leon J

    2015-11-01

    Vitamin K-antagonists (VKA) are the most widely used anticoagulant drugs to treat patients at risk of arterial and venous thrombosis for the past 50 years. Due to unfavorable pharmacokinetics VKA have a small therapeutic window, require frequent monitoring, and are susceptible to drug and nutritional interactions. Additionally, the effect of VKA is not limited to coagulation, but affects all vitamin K-dependent proteins. As a consequence, VKA have detrimental side effects by enhancing medial and intimal calcification. These limitations stimulated the development of alternative anticoagulant drugs, resulting in direct oral anticoagulant (DOAC) drugs, which specifically target coagulation factor Xa and thrombin. DOACs also display non-hemostatic vascular effects via protease-activated receptors (PARs). As atherosclerosis is characterized by a hypercoagulable state indicating the involvement of activated coagulation factors in the genesis of atherosclerosis, anticoagulation could have beneficial effects on atherosclerosis. Additionally, accumulating evidence demonstrates vascular benefit from high vitamin K intake. This review gives an update on oral anticoagulant treatment on the vasculature with a special focus on calcification and vitamin K interaction. PMID:26593943

  17. Lupus anticoagulants: pathogenesis and laboratory diagnosis.

    Science.gov (United States)

    Court, E L

    1997-12-01

    The pathogenesis of the lupus anticoagulant (LA) has been the focus of much research over the past decade, and a plethora of laboratory tests have been developed to detect it. This essay reviews the nature of LA and its pathogenesis, and a number of approaches employed in its diagnosis. These range from well established tests such as the kaolin clotting time (KCT), activated partial thromboplastin time (APTT) and tissue thromboplastin inhibition test (TTI), to the 'newer' tests such as the dilute Russell's viper venom time (DRVVT) and more recent snake venom tests such as the textarin/ecarin ratio and Taipan snake venom time (TSVT). The criteria for diagnosis are discussed, including pre-analytical variables such as sample preparation, and the effects of therapeutic anticoagulants used to treat thrombotic manifestations of the syndrome or an underlying disease process. PMID:9624740

  18. Degradation of Activated Protein Kinases by Ubiquitination

    OpenAIRE

    Lu, Zhimin; Hunter, Tony

    2009-01-01

    Protein kinases are important regulators of intracellular signal transduction pathways and play critical roles in diverse cellular functions. Once a protein kinase is activated, its activity is subsequently downregulated through a variety of mechanisms. Accumulating evidence indicates that the activation of protein kinases commonly initiates their downregulation via the ubiquitin/proteasome pathway. Failure to regulate protein kinase activity or expression levels can cause human diseases.

  19. Anticoagulation therapy in intra-aortic balloon counterpulsation: Does IABP really need anti-coagulation

    Institute of Scientific and Technical Information of China (English)

    蒋晨阳; 赵莉莉; 王建安; 单江; MOHAMMODBalgaith

    2003-01-01

    Objective: To investigate if intra-aortic balloon pump(IABP) is contraindicated without anticoag-ulation therapy. Methods: Some 153 IABP patients in the King Abdulaziz Cardiac Center(KSA) were random-ly assigned into two groups. Anticoagulation group( Group A) consisted of 71 patients who were given heparin intravenously with target aPTT 50 - 70 seconds. Non-anticoagulation group( Group B) consisted of 82 patients without intravenous heparin during balloon pumping. Hematological parameters including platelet count, D-dimer, Plasminogen activator inhibitor-1 (PAI-1) and fibrinogen degradation products(FDP) were checked respectively at the point of baseline, 24 hours, 48 hours and 24 hours post IABP counterpulsation. Clot deposits on balloon surface, vascular complications from IABP including bleeding and limb ischemia were recorded.Results: Platelet count and PAI-1 level decreased at 24 hours and 48 hours in both groups ( P 0.05) . Three patients in Group A and 2 patients in Group B developed minor limb ischemia( P > 0.05). No major limb ischemia in either group. Two patients in Group A suffered major bleeding and required blood transfusion or surgical intervention, whereas no patient had major bleeding in Group B. Eight patients had minor bleeding in Group A, but only 2 patients in Group B ( P <0.05). No clot deposit developed on IABP surface in either group. Conclusion: IABP is safe without routine anticoagulation therapy. Selecting appropriate artery approach and early detection intervention are key methods for preventing complications.

  20. Anticoagulation therapy in intra-aortic balloon counterpulsation:Does IABP really need anti-coagulation?

    Institute of Scientific and Technical Information of China (English)

    JIANG Chen-yang(蒋晨阳); ZHAO Li-li(赵莉莉); WANG Jian-an(王建安); SAN Jiang(单江); MOHAMMOD Balgaith

    2003-01-01

    Objective: To investigate if intra-aortic balloon pump(IABP) is contraindicated without anticoagulation therapy. Methods: Some 153 IABP patients in the King Abdulaziz Cardiac Center(KSA) were randomly assigned into two groups. Anticoagulation group(Group A) consisted of 71 patients who were given heparin intravenously with target aPTT 50-70 seconds. Non-anticoagulation group(Group B) consisted of 82 patients without intravenous heparin during balloon pumping. Hematological parameters including platelet count, D-dimer, Plasminogen activator inhibitor-1(PAI-1) and fibrinogen degradation products(FDP) were checked respectively at the point of baseline, 24 hours, 48 hours and 24 hours post IABP counterpulsation. Clot deposits on balloon surface, vascular complications from IABP including bleeding and limb ischemia were recorded. Results: Platelet count and PAI-1 level decreased at 24 hours and 48 hours in both groups (P0.05). Three patients in Group A and 2 patients in Group B developed minor limb ischemia(P>0.05). No major limb ischemia in either group. Two patients in Group A suffered major bleeding and required blood transfusion or surgical intervention, whereas no patient had major bleeding in Group B. Eight patients had minor bleeding in Group A, but only 2 patients in Group B(P<0.05). No clot deposit developed on IABP surface in either group. Conclusion: IABP is safe without routine anticoagulation therapy. Selecting appropriate artery approach and early detection intervention are key methods for preventing complications.

  1. Anticoagulation Considerations for Travel to High Altitude.

    Science.gov (United States)

    DeLoughery, Thomas G

    2015-09-01

    DeLoughery, Thomas G. Anticoagulation considerations for travel to high altitude. High Alt Med Biol 16:181-185, 2015.-An increasing percentage of the population are on anticoagulation medicine for clinical reasons ranging from stroke prevention in atrial fibrillation to long term prevention of deep venous thrombosis. In recent years, several new direct oral anticoagulants have entered the market. The key questions that should be kept in mind when approaching a potential traveler on anticoagulation are: 1) why is the patient on anticoagulation? 2) do they need to stay on anticoagulation? 3) what are the choices for their anticoagulation? 4) will there be any drug interactions with medications needed for travel? and 5) how will they monitor their anticoagulation while traveling? Knowing the answers to these questions then can allow for proper counseling and planning for the anticoagulated traveler's trip. PMID:26186419

  2. Does plasmin have anticoagulant activity?

    OpenAIRE

    Jane Hoover-Plow

    2010-01-01

    Jane Hoover-PlowJoseph J Jacobs Center for Thrombosis and Vascular Biology, Departments of Cardiovascular Medicine and Molecular Cardiology, Lerner Research Institute Cleveland Clinic, Ohio, USAAbstract: The coagulation and fibrinolytic pathways regulate hemostasis and thrombosis, and an imbalance in these pathways may result in pathologic hemophilia or thrombosis. The plasminogen system is the primary proteolytic pathway for fibrinolysis, but also has important proteolytic functions in cell ...

  3. Activated protein C attenuates acute ischaemia reperfusion injury in skeletal muscle.

    LENUS (Irish Health Repository)

    Dillon, J P

    2012-02-03

    Activated protein C (APC) is an endogenous anti-coagulant with anti-inflammatory properties. The purpose of the present study was to evaluate the effects of activated protein C in the setting of skeletal muscle ischaemia reperfusion injury (IRI). IRI was induced in rats by applying rubber bands above the levels of the greater trochanters bilaterally for a period of 2h followed by 12h reperfusion. Treatment groups received either equal volumes of normal saline or activated protein C prior to tourniquet release. Following 12h reperfusion, muscle function was assessed electrophysiologically by electrical field stimulation. The animals were then sacrificed and skeletal muscle harvested for evaluation. Activated protein C significantly attenuated skeletal muscle reperfusion injury as shown by reduced myeloperoxidase content, wet to dry ratio and electrical properties of skeletal muscle. Further in vitro work was carried out on neutrophils isolated from healthy volunteers to determine the direct effect of APC on neutrophil function. The effects of APC on TNF-alpha stimulated neutrophils were examined by measuring CD18 expression as well as reactive oxygen species generation. The in vitro work demonstrated a reduction in CD18 expression and reactive oxygen species generation. We conclude that activated protein C may have a protective role in the setting of skeletal muscle ischaemia reperfusion injury and that this is in part mediated by a direct inhibitory effect on neutrophil activation.

  4. Avaliação do desempenho dos reagentes do tempo de tromboplastina parcial ativada utilizados para detectar o anticoagulante lúpico Assessment of the performance of reagents of activated partial thromboplastin time used to detect the lupus anticoagulant

    Directory of Open Access Journals (Sweden)

    Fernanda Chiuso

    2005-06-01

    Full Text Available INTRODUÇÃO: O anticoagulante lúpico é uma imunoglobulina pertencente à família dos anticorpos antifosfolípides. A sua ação in vitro é interferir nos testes de coagulação dependentes de fosfolípides. O tempo de tromboplastina parcial ativada (TTPA é um teste utilizado como screening na pesquisa do anticoagulante lúpico. Os reagentes utilizados neste teste apresentam grandes variações quanto à sensibilidade. OBJETIVO: Avaliar o desempenho dos reagentes do TTPA e detectar a presença do anticoagulante lúpico através de diferentes testes da coagulação. MATERIAL E MÉTODO: A pesquisa do anticoagulante lúpico foi realizada em 50 amostras plasmáticas de pacientes do sexo feminino através dos testes do TTPA, do tempo de coagulação do caulim (TCC, do tempo de tromboplastina parcial ativada diluída (TTPAd e do tempo do veneno da víbora de Russel diluído (TVVRd. Três cefalinas comerciais foram avaliadas pelos testes do TTPA e do TTPAd. Na comparação entre os reagentes estudados foi aplicado o cálculo do intervalo de confiança (95%. RESULTADOS: Os três reagentes avaliados apresentaram boa concordância e os métodos utilizados responderam bem à pesquisa do anticoagulante lúpico. DISCUSSÃO E CONCLUSÃO: As três cefalinas comerciais avaliadas podem ser utilizadas na rotina laboratorial para a pesquisa do anticoagulante lúpico.INTRODUCTION: The lupus anticoagulant is an immunoglobin which belongs to the antiphospholid antibodies family. Its in vitro function is to interfere with coagulation tests that are dependent on phospholipids. The activated partial thromboplastin time (APTT is a test used as screening on lupus anticoagulant research. Reagents used in this test demonstrate wide sensitivity ranges. OBJECTIVE: To assess the performance of APTT reagents and detect the presence of lupus anticoagulant through various coagulation tests. MATERIAL AND METHOD: The lupus anticoagulant research was performed in plasma from 50

  5. Physiological roles of mitogen-activated-protein-kinase-activated p38-regulated/activated protein kinase

    Institute of Scientific and Technical Information of China (English)

    Sergiy; Kostenko; Gianina; Dumitriu; Kari; Jenssen; Lgreid; Ugo; Moens

    2011-01-01

    Mitogen-activated protein kinases(MAPKs)are a family of proteins that constitute signaling pathways involved in processes that control gene expression,cell division, cell survival,apoptosis,metabolism,differentiation and motility.The MAPK pathways can be divided into conventional and atypical MAPK pathways.The first group converts a signal into a cellular response through a relay of three consecutive phosphorylation events exerted by MAPK kinase kinases,MAPK kinase,and MAPK.Atypical MAPK pathways are not organized into this three-tiered cascade.MAPK that belongs to both conventional and atypical MAPK pathways can phosphorylate both non-protein kinase substrates and other protein kinases.The latter are referred to as MAPK-activated protein kinases.This review focuses on one such MAPK-activated protein kinase,MAPK-activated protein kinase 5(MK5)or p38-regulated/activated protein kinase(PRAK).This protein is highly conserved throughout the animal kingdom and seems to be the target of both conventional and atypical MAPK pathways.Recent findings on the regulation of the activity and subcellular localization,bona fide interaction partners and physiological roles of MK5/PRAK are discussed.

  6. Pharmacology of new oral anticoagulants: mechanism of action, pharmacokinetics, pharmacodynamics

    Directory of Open Access Journals (Sweden)

    Luca Masotti

    2013-12-01

    Full Text Available Due to their mechanism of action, the new oral anticoagulants are named direct oral anticoagulants (DOACs. Dabigatran is a selective, competitive, direct inhibitor of thrombin (Factor IIa while rivaroxaban, apixaban and edoxaban act by directly inhibiting the activated Factor X (FXa in a selective and competitive manner. DOACs have a relatively short half-life and almost immediate anticoagulant activity, and rapidly reach the plasma peak concentration. Therefore, they do not need a phase of overlapping with parenteral anticoagulants. After their withdrawal, their removal is sufficiently rapid, although influenced by renal function. Dabigatran is the only DOACs to be administered as a pro-drug and becomes active after drug metabolization. The route of elimination of dabigatran is primarily renal, whereas FXa inhibitors are mainly eliminated by the biliary-fecal route. The drug interactions of DOACs are mainly limited to drugs that act on P-glycoprotein for dabigatran and on P-glycoprotein and/or cytochrome P3A4 for anti-Xa. DOACs have no interactions with food. Given their linear pharmacodynamics, with a predictable dose/response relationship and anticoagulant effect, DOACs are administered at a fixed dose and do not require routine laboratory monitoring.

  7. Interference from lupus anticoagulant on von Willebrand factor measurement in splenic marginal zone lymphoma

    DEFF Research Database (Denmark)

    Vinholt, Pernille J; Nybo, Mads

    2015-01-01

    We present a case concerning a patient with splenic marginal zone lymphoma (SMZL) and isolated prolonged activated partial thromboplastin time (aPTT) caused by lupus anticoagulant. Von Willebrand factor (VWF) activity and antigen were immeasurable by latex particle immunoturbidimetric assays, and...... several coagulation factor levels were decreased. However, VWF activity and antigen were normal when analyzed by other methods. Also, coagulation factor levels were normal if an aPTT reagent with low lupus anticoagulant sensitivity or a chromogenic method was applied. Altogether, the initial findings were...... because of lupus anticoagulant interference and in fact, the patient had normal VWF activity and coagulation status. Interference of lupus anticoagulant in clot-based assays is well known but has not previously been described in VWF assays. This is furthermore the first report in which lupus anticoagulant...

  8. Anticoagulation in Pulmonary Arterial Hypertension.

    Science.gov (United States)

    Robinson, Jeffrey C; Pugliese, Steven C; Fox, Daniel L; Badesch, David B

    2016-06-01

    Pulmonary arterial hypertension (PAH) is characterized by molecular and pathologic alteration to the pulmonary circulation, resulting in increased pulmonary vascular resistance, right ventricular failure, and eventual death. Pharmacologic treatment of PAH consists of use of a multitude of pulmonary vasodilators, sometimes in combination. PAH has been associated with increased thrombosis and disrupted coagulation and fibrinolysis, making anticoagulation an attractive and frequently employed therapeutic modality. Observational studies have provided some insight into the therapeutic potential of anticoagulation in idiopathic PAH, but there is a distinct lack of well-controlled prospective trials. Due to the conflicting evidence, there is a large amount of heterogeneity in the application of therapeutic anticoagulation in PAH and further well-controlled prospective trials are needed to clarify its role in treating PAH. PMID:27137522

  9. Protein-water dynamics in antifreeze protein III activity

    Science.gov (United States)

    Xu, Yao; Bäumer, Alexander; Meister, Konrad; Bischak, Connor G.; DeVries, Arthur L.; Leitner, David M.; Havenith, Martina

    2016-03-01

    We combine Terahertz absorption spectroscopy (THz) and molecular dynamics (MD) simulations to investigate the underlying molecular mechanism for the antifreeze activity of one class of antifreeze protein, antifreeze protein type III (AFP-III) with a focus on the collective water hydrogen bond dynamics near the protein. After summarizing our previous work on AFPs, we present a new investigation of the effects of cosolutes on protein antifreeze activity by adding sodium citrate to the protein solution of AFP-III. Our results reveal that for AFP-III, unlike some other AFPs, the addition of the osmolyte sodium citrate does not affect the hydrogen bond dynamics at the protein surface significantly, as indicated by concentration dependent THz measurements. The present data, in combination with our previous THz measurements and molecular simulations, confirm that while long-range solvent perturbation is a necessary condition for the antifreeze activity of AFP-III, the local binding affinity determines the size of the hysteresis.

  10. Characterization of the protein C activator Protac from the venom of the southern copperhead (Agkistrodon contortrix) snake.

    Science.gov (United States)

    Stocker, K; Fischer, H; Meier, J; Brogli, M; Svendsen, L

    1987-01-01

    A single chain glycopeptide with a molecular weight of approximately 37,000, an isoelectric point of 3.0 +/- 0.2 and a carbohydrate content of approximately 20% was isolated from the venom of the southern copperhead Agkistrodon contortrix contortrix. It was capable of converting zymogen protein C in plasma of man and various vertebrates into its activated form, a serine proteinase which exerts an anticoagulant effect. Conversion of the zymogen protein C into the active proteinase was demonstrated by measuring the prolongation of the activated partial thromboplastin time due to proteolytic degradation of factors Va and VIIIa by the activation product, as well as by direct measurement of the generated enzyme activity by means of a synthetic chromogenic substrate. Intravenous injection of the venom protein C activator into rabbits caused prolonged activated partial thromboplastin time. Repeated subcutaneous injections led to formation of an antibody which formed, with purified protein C activator as well as with crude A. contortrix venom, a precipitating complex devoid of protein C activator potency. As revealed by activity measurements and by immunodiffusion experiments, the venoms of various A. contortrix, A. bilineatus subspecies contain similar protein C activators. PMID:3590209

  11. Activity assay of membrane transport proteins

    Institute of Scientific and Technical Information of China (English)

    Hao Xie

    2008-01-01

    Membrane transport proteins are integral membrane proteins and considered as potential drug targets. Activity assay of transport proteins is essential for developing drugs to target these proteins. Major issues related to activity assessment of transport proteins include availability of transporters,transport activity of transporters, and interactions between ligands and transporters. Researchers need to consider the physiological status of proteins (bound in lipid membranes or purified), availability and specificity of substrates, and the purpose of the activity assay (screening, identifying, or comparing substrates and inhibitors) before choosing appropriate assay strategies and techniques. Transport proteins bound in vesicular membranes can be assayed for transporting substrate across membranes by means of uptake assay or entrance counterflow assay. Alternatively, transport proteins can be assayed for interactions with ligands by using techniques such as isothermal titration calorimetry, nuclear magnetic resonance spectroscopy, or surface plasmon resonance. Other methods and techniques such as fluorometry, scintillation proximity assay, electrophysiological assay, or stopped-flow assay could also be used for activity assay of transport proteins. In this paper the major strategies and techniques for activity assessment of membrane transport proteins are reviewed.

  12. Anticoagulation in Older Adults with Multimorbidity.

    Science.gov (United States)

    Parks, Anna L; Fang, Margaret C

    2016-05-01

    The number of patients with atrial fibrillation (AF) who are of advanced age or have multiple comorbidities is expected to increase substantially. Older patients with AF generally gain a net benefit from anticoagulation. Guidelines typically recommend anticoagulation. There are multiple challenges in the safe use of anticoagulation in frail patients, including bleeding risk, monitoring and adherence, and polypharmacy. Although there are options for chronic oral anticoagulation, clinicians must understand the unique advantages and disadvantages of these medications when developing a management plan. This article reviews issues surrounding the appropriate use and selection of anticoagulants in complex older patients with AF. PMID:27113150

  13. 3K3A-activated protein C stimulates postischemic neuronal repair by human neural stem cells in mice

    DEFF Research Database (Denmark)

    Wang, Yaoming; Zhao, Zhen; Rege, Sanket V;

    2016-01-01

    -APC (Lys191-193Ala) mutant in which three Lys residues (KKK191-193) were replaced with alanine, and/or its other mutants with reduced (>90%) anticoagulant activity, engineered to reduce APC-associated bleeding risk while retaining normal cell-signaling activity, have shown benefits in preclinical models...... profile in humans, 3K3A-APC has advanced to clinical trials as a neuroprotectant in ischemic stroke. Recently, 3K3A-APC has been shown to stimulate neuronal production by human neural stem and progenitor cells (NSCs) in vitro via a PAR1-PAR3-sphingosine-1-phosphate-receptor 1-Akt pathway, which suggests......Activated protein C (APC) is a blood protease with anticoagulant activity and cell-signaling activities mediated by the activation of protease-activated receptor 1 (F2R, also known as PAR1) and F2RL1 (also known as PAR3) via noncanonical cleavage. Recombinant variants of APC, such as the 3K3A...

  14. Pharmacokinetic and pharmacodynamic properties of oral anticoagulants, especially phenprocoumon.

    Science.gov (United States)

    Haustein, K O

    1999-01-01

    Anticoagulants of the cumarin-type (warfarin, phenprocoumon, and acenocoumarol) are drugs for the long-term treatment and prevention of thromboembolic disorders. Because of their narrow therapeutic range, many patients have bleedings of variable severity or have recurrent thrombotic events. For this reason, the study of the pharmacokinetic parameters of phenprocoumon (PPC), considering its influence on blood clotting factors, is of high interest. The elimination kinetics of PPC, its interaction with phytomenadion (vitamin K), and the pharmacokinetic behavior of the anticoagulant under steady-state conditions have been investigated in studies with healthy volunteers and patients taking anticoagulants. The maintenance dose and the plasma levels of PPC were correlated with prothrombin time (PT) in 89 patients treated with PPC. Varying parameters in each patient (e.g., elimination kinetics of PPC, activity of the cumarin-dependent blood-clotting factors, endogenous phytomenadion stores), render it impossible to use a different means of monitoring than that of PT determination. PMID:10327214

  15. Activity-Based Protein Profiling of Microbes

    Energy Technology Data Exchange (ETDEWEB)

    Sadler, Natalie C.; Wright, Aaron T.

    2015-02-01

    Activity-Based Protein Profiling (ABPP) in conjunction with multimodal characterization techniques has yielded impactful findings in microbiology, particularly in pathogen, bioenergy, drug discovery, and environmental research. Using small molecule chemical probes that react irreversibly with specific proteins or protein families in complex systems has provided insights in enzyme functions in central metabolic pathways, drug-protein interactions, and regulatory protein redox, for systems ranging from photoautotrophic cyanobacteria to mycobacteria, and combining live cell or cell extract ABPP with proteomics, molecular biology, modeling, and other techniques has greatly expanded our understanding of these systems. New opportunities for application of ABPP to microbial systems include: enhancing protein annotation, characterizing protein activities in myriad environments, and reveal signal transduction and regulatory mechanisms in microbial systems.

  16. New oral anticoagulants – a practical guide

    Science.gov (United States)

    Ciurus, Tomasz; Sobczak, Sebastian; Cichocka-Radwan, Anna

    2015-01-01

    Oral direct inhibitors of thrombin and activated factor Xa are approved as new anticoagulant drugs. In contrast to vitamin K antagonists (VKA) and heparins, the new agents have single targets in the coagulation cascade and more predictable pharmacokinetics, but they lack validated and available antidotes. Unlike VKA, they do not require routine monitoring of coagulation. However, the measurement of their pharmacologic effects might be of value in selected patients. They interfere with the routine coagulation tests, which should be interpreted with caution. Specific tests exist and can be used in case of emergencies. Adequate supportive care and temporary removal of all antithrombotic agents constitute the basis for management of serious bleeding complications. The administration of coagulation factors, such as fresh frozen plasma, prothrombin complex concentrates or recombinant activated FVII, can benefit in life-threatening bleeding or emergency surgery. Specific antidotes for non-vitamin K oral anticoagulants are in clinical development. This review aims at answering in a brief and simplified manner some clinical questions. PMID:26336492

  17. Evaluation of anticoagulant control in a pharmacist operated anticoagulant clinic.

    OpenAIRE

    Radley, A S; Hall, J; Farrow, M.; Carey, P J

    1995-01-01

    AIMS--To compare the quality of outpatient anticoagulant control before and after the transfer of dosing responsibility to designated trained pharmacists from rotating junior medical staff. METHODS--All International Normalised Ratio (INR) values for an eight month period either side of the staff changeover were assessed for precision of therapeutic control according to described standards. Allowing for patient associated effects, observed and expected frequencies of "successful" control for ...

  18. Differential expression of cytochrome P450 genes between bromadiolone-resistant and anticoagulant-susceptible Norway rats

    DEFF Research Database (Denmark)

    Markussen, Mette Drude Kjær; Heiberg, Ann-Charlotte; Fredholm, Merete;

    2008-01-01

    Background: Anticoagulant resistance in Norway rats, Rattus norvegicus (Berk.), has been suggested to be conferred by mutations in the VKORC1 gene, encoding the target protein of anticoagulant rodenticides. Other factors, e.g. pharmacokinetics, may also contribute to resistance, however. To examine...

  19. Differential expression of cytochrome P450 genes between bromadiolone-resistant and anticoagulant-susceptible Norway rats:

    DEFF Research Database (Denmark)

    Markussen, Mette Drude; Heiberg, Ann-Charlotte; Fredholm, Merete;

    2008-01-01

    Anticoagulant resistance in Norway rats (Rattus norvegicus) has been suggested to be due to mutations in the VKORC1 gene, encoding the target protein of anticoagulant rodenticides such as warfarin and bromadiolone. Other factors, e.g. pharmacokinetics, may however also contribute to resistance. W...

  20. Structure and anticoagulant properties of sulfated glycosaminoglycans from primitive Chordates

    Directory of Open Access Journals (Sweden)

    PAVÃO MAURO S. G.

    2002-01-01

    Full Text Available Dermatan sulfates and heparin, similar to the mammalian glycosaminoglycans, but with differences in the degree and position of sulfation were previously isolated from the body of the ascidian Styela plicata and Ascidia nigra. These differences produce profound effects on their anticoagulant properties. S. plicata dermatan sulfate composed by 2-O-sulfatedalpha-L-iduronic acid and 4-O-sulfated N-acetyl-beta-D-galactosamine residues is a potent anticoagulant due to a high heparin cofactor II activity. Surprisingly, it has a lower potency to prevent thrombus formation on an experimental model and a lower bleeding effect in rats than the mammalian dermatan sulfate. In contrast, A. nigra dermatan sulfate, also enriched in 2-O-sulfated alpha-L-iduronic acid, but in this case sulfated at O-6 of the N-acetyl-beta-D-galactosamine units, has no in vitro or in vivo anticoagulant activity, does not prevent thrombus formation but shows a bleeding effect similar to the mammalian glycosaminoglycan. Ascidian heparin, composed by 2-O-sulfated alpha-L-iduronic acid, N- and 6-O-sulfated glucosamine (75% and alpha-L-iduronic acid, N- and 6-O-sulfated glucosamine (25% disaccharide units has an anticoagulant activity 10 times lower than the mammalian heparin, is about 20 times less potent in the inhibition of thrombin by antithrombin, but has the same heparin cofactor II activity as mammalian heparin.

  1. [Pharmacologic heterogeneity of new anticoagulants].

    Science.gov (United States)

    Samamaa, M-M; Conard, J; Flaujac, C; Combe, S; Horellou, M-H

    2011-12-01

    Amongst numerous promising anticoagulant molecules, rivaroxaban (Xarelto(®)), dabigatran (Pradaxa(®)) and apixaban (Eliquis(®)) have been registered outside the USA in the prevention of thromboembolic events in patients undergoing total hip or knee prosthetic replacement. Rivaroxaban however has been granted authorisation by the FDA for the thromboprophylaxis after surgery for total hip or knee surgery. Dabigatran has been granted authorisation by the FDA in non-valvular atrial fibrillation (RE-LY trial) while rivaroxaban is expecting approval in this same indication (ROCKET trial). Phase III results in the treatment and in the secondary prevention of established venous thrombosis and pulmonary embolism are encouraging. These small molecules are obtained by chemical synthesis, their molecular weight is lower than 500 daltons. Many coagulation tests may be affected by these molecules. Those modifications should be known in order to avoid misinterpretation of the tests but could also be used to measure plasma concentrations of these products. The choice of a non specific global and readily available test has been documented (Quick time for rivaroxaban and aPTT for dabigatran). Anti-Xa (for rivaroxaban) and anti-IIa (for dabigatran) activities should however be preferred, expressed in ng/ml with calibrated plasmas (containing predetermined concentration of the tested drug). The half-life is around 8 to 12 hours, with a peak activity 2 to 4 hours after ingestion. Dabigatran is mainly eliminated via the kidney, hence requiring dose-adjustment in case of moderate renal insufficiency, and contra-indicated in case of severe renal insufficiency. Rivaroxaban being excreted via kidney and liver, some precautions should apply in case of liver insufficiency. No data are available in pregnancy or pediatrics, clinical trials are ongoing. There are few interactions with concomitant drugs, which should not be ignored. The short half-life of these new agents compensates for the

  2. The challenges of lupus anticoagulants.

    Science.gov (United States)

    Chighizola, Cecilia Beatrice; Raschi, Elena; Banzato, Alessandra; Borghi, Maria Orietta; Pengo, Vittorio; Meroni, Pier Luigi

    2016-01-01

    The term "lupus anticoagulant" (LA) refers to a heterogeneous group of immunoglobulins behaving as acquired in vitro inhibitors of coagulation. These antibodies, namely anti-β2GPI and anti-prothrombin antibodies, induce the in vitro elongation of clotting time interfering with phospholipid-dependent coagulation cofactors. Positive LA is associated with thrombosis and pregnancy complications, providing one of the three laboratory criteria for the classification of the anti-phospholipid syndrome. LA is the strongest predictor of clinical events, especially when associated with other anti-phospholipid antibodies. Much more controversial is the risk conveyed by isolated and weak LA. LA detection is technically laborious, envisaging screening, mixing and confirming tests. Hopefully critical issues in LA detection, such as the interference of anticoagulants, will be overcome, in the next future. PMID:26789237

  3. Anticoagulants used in plasma collection affect adipokine multiplexed measurements.

    Science.gov (United States)

    Allione, Alessandra; Di Gaetano, Cornelia; Dani, Nadia; Barberio, Davide; Sieri, Sabina; Krogh, Vittorio; Matullo, Giuseppe

    2016-04-01

    Obesity is an important health problem worldwide. Adipose tissue acts as an endocrine organ that secretes various bioactive substances, called adipokines, including pro-inflammatory biomarkers such as TNF-α, IL-6, leptin and C-reactive protein (CRP) and anti-inflammatory molecules such as adiponectin. The deregulated production of adipokines in obesity is linked to the pathogenesis of various disease processes and monitoring their variation is critical to understand metabolic diseases. The aim of this study was to determine the plasma concentration of adipokines in healthy subjects by multiplexed measurements and the effect of anticoagulants on their levels. Plasma samples from 10 healthy donors were collected in two different anticoagulants (sodium citrate or heparin). All markers, excluding TNF-α, showed significantly higher concentrations in heparinized compared to citrate plasma. However, levels of adipokines in different plasma samples were highly correlated for most of these markers. We reported that different anticoagulants used in the preparation of the plasma samples affected the measurements of some adipokines. The importance of the present results in epidemiology is relevant when comparing different studies in which blood samples were collected with different anticoagulants. PMID:26945995

  4. Coagulation inhibitors and activated protein C resistance in recurrent pregnancy losses in Indian women

    Directory of Open Access Journals (Sweden)

    P Lalita Jyotsna

    2011-01-01

    Full Text Available Background: Thrombophilias, both acquired and inherited, have been investigated in the etiopathogenesis of unexplained recurrent pregnancy loss. Aim: To study coagulation inhibitors and activated protein C resistance (APCR in recurrent pregnancy losses (RPL occurring in second and third trimesters. Materials and Methods: A total of 30 pregnant women (group A with two or more recurrent unexplained fetal loses were evaluated for APCR, protein C deficiency, protein S deficiency, antithrombin deficiency, and antiphospholipid antibodies (APLA. Thirty age-matched controls were taken (group B comprising of pregnant women with at least one live issue. Statistical Analysis: Comparisons between two group frequencies and group means were made using Chi square test and Student′s t test, respectively. Results: Protein C and protein S levels were reduced in group A compared with group B and the difference was statistically significant (P=0.005 and P=0.032, respectively. The mean value of antithrombin was slightly reduced in group A compared with group B. APCR was observed in 16.6% cases and 3.3% controls. However, the difference was not statistically significant. APLA was observed in 20% cases and none of the controls. Of these, lupus anticoagulant was positive in 16.6% cases and anticardiolipin antibodies in 10% cases. Combined defects were seen in seven patients. Conclusion: There is a significant risk of RPL in pregnant women with thrombophilias. Therefore, screening for thrombophilias may be justified in pregnant women with unexplained recurrent fetal wastage, especially in second and third trimester.

  5. New oral anticoagulants: key messages for clinicians

    Directory of Open Access Journals (Sweden)

    Matteo Giorgi-Pierfranceschi

    2013-12-01

    Full Text Available New oral anticoagulants are an effective and safe alternative to vitamin K antagonists in many fields of clinical practice. The use of the direct inhibitors of activated Factor II (dabigatran and activated Factor X (apixaban and rivaroxaban, both in patients with non-valvular atrial fibrillation (NVAF and those with acute venous thromboembolism (VTE, is of great interest for internal medicine physicians. This paper aims to give practical guidance on management (starting therapy, follow up and bleeding complications of patients treated with dabigatran, rivaroxaban or apixaban for NVAF or acute VTE providing practical tables concerning the phases of therapy, management of complications, drug interaction and dose adjustment if renal impairment occurs.

  6. Modulation of mitogen-activated protein kinase-activated protein kinase 3 by hepatitis C virus core protein

    DEFF Research Database (Denmark)

    Ngo, HT; Pham, Long; Kim, JW;

    2013-01-01

    , approximately 100 cellular proteins were identified as HCV core-interacting partners. Of these candidates, mitogen-activated protein kinase-activated protein kinase 3 (MAPKAPK3) was selected for further characterization. MAPKAPK3 is a serine/threonine protein kinase that is activated by stress and growth...... inducers. Binding of HCV core to MAPKAPK3 was confirmed by in vitro pulldown assay and further verified by coimmunoprecipitation assay. HCV core protein interacted with MAPKAPK3 through amino acid residues 41 to 75 of core and the N-terminal half of kinase domain of MAPKAPK3. In addition, both RNA and......Hepatitis C virus (HCV) is highly dependent on cellular proteins for its own propagation. In order to identify the cellular factors involved in HCV propagation, we performed protein microarray assays using the HCV core protein as a probe. Of ~9,000 host proteins immobilized in a microarray...

  7. DNA-based control of protein activity.

    Science.gov (United States)

    Engelen, W; Janssen, B M G; Merkx, M

    2016-03-01

    DNA has emerged as a highly versatile construction material for nanometer-sized structures and sophisticated molecular machines and circuits. The successful application of nucleic acid based systems greatly relies on their ability to autonomously sense and act on their environment. In this feature article, the development of DNA-based strategies to dynamically control protein activity via oligonucleotide triggers is discussed. Depending on the desired application, protein activity can be controlled by directly conjugating them to an oligonucleotide handle, or expressing them as a fusion protein with DNA binding motifs. To control proteins without modifying them chemically or genetically, multivalent ligands and aptamers that reversibly inhibit their function provide valuable tools to regulate proteins in a noncovalent manner. The goal of this feature article is to give an overview of strategies developed to control protein activity via oligonucleotide-based triggers, as well as hurdles yet to be taken to obtain fully autonomous systems that interrogate, process and act on their environments by means of DNA-based protein control. PMID:26812623

  8. Anticoagulant Medicine: Potential for Drug-Food Interactions

    Science.gov (United States)

    ... AerobiKa® Cardiology Medications Anticoagulant Medicine Anticoagulants and Drug-Food Interactions COPD Medications Bronchodilators Anti-Inflammatories Antibiotics Managing Your Medications Devices ...

  9. Multicomponent determination of 4-hydroxycoumarin anticoagulant rodenticides in blood serum by liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Felice, L J; Chalermchaikit, T; Murphy, M J

    1991-01-01

    A sensitive liquid chromatographic method was developed for the analysis of 4-hydroxycoumarin anticoagulant rodenticides in blood serum. The method can simultaneously measure the serum levels of five anticoagulant rodenticides: brodifacoum, bromadiolone, coumatetralyl, difenacoum, and warfarin. Serum proteins are precipitated with acetonitrile and the supernatant is mixed with ethyl ether. The organic phase is separated, evaporated to dryness, and the residue subjected to chromatographic analysis. The anticoagulants are separated by reversed-phase gradient chromatography with fluorescence detection at an excitation wavelength of 318 nm and emission wavelength of 390 nm. Extraction efficiencies of 68.1 to 98.2% were obtained. The within-run precision (CV) ranged from 2.19 to 3.79% and the between-run precision (CV) from 3.72 to 9.57%. The anticoagulants can be quantitated at serum levels of 10 to 20 ng/mL. PMID:1943055

  10. Anticoagulant, antiplatelet and antianemic effects of Punica granatum (pomegranate) juice in rabbits.

    Science.gov (United States)

    Riaz, Azra; Khan, Rafeeq A

    2016-04-01

    Pomegranate (Punica granatum L., Punicaceae) is a good source of minerals and phytochemicals with diverse pharmacological activities such as anxiolytic, antidepressant, hypoglycemic, hypolipidemic, and anti-inflammatory activities. Effects of P. granatum on blood parameters and coagulation have, however, been little studied. The aim of the study was to assess the outcome of P. granatum on coagulation and anticoagulation factors at different doses on blood samples of healthy white rabbits. Blood samples of the animals were collected twice during the study and biochemical assays were performed to assess the effect on hematological, coagulation, anticoagulation, and platelet aggregation. Significant changes were observed in erythrocytes, hemoglobin, and mean corpuscular hemoglobin concentration, while bleeding and thrombin time were also prolonged significantly. There was significant increase in protein C, thrombin antithrombin complex levels, and decrease in platelet aggregation and fibrinogen concentration, in a dose-dependent manner. The results of hematological and coagulation assays lead to the speculation about a possible antianemic and cardioprotective effect of P. granatum. PMID:26881853

  11. Human Monoclonal Antiphospholipid Antibodies Disrupt the Annexin A5 Anticoagulant Crystal Shield on Phospholipid Bilayers

    Science.gov (United States)

    Rand, Jacob H.; Wu, Xiao-Xuan; Quinn, Anthony S.; Chen, Pojen P.; McCrae, Keith R.; Bovill, Edwin G.; Taatjes, Douglas J.

    2003-01-01

    The antiphospholipid (aPL) syndrome is an autoimmune condition that is marked by recurrent pregnancy losses and/or systemic vascular thrombosis in patients who have antibodies against phospholipid/co-factor complexes. The mechanism(s) for pregnancy losses and thrombosis in this condition is (are) not known. Annexin A5 is a potent anticoagulantprotein, expressed by placental trophoblasts and endothelial cells, that crystallizes over anionic phospholipids, shielding them from availability for coagulation reactions. We previously presented data supporting the hypothesis that aPL antibody-mediated disruption of the anticoagulant annexin A5 shield could be a thrombogenic mechanism in the aPL syndrome. However, this has remained a subject of controversy. We therefore used atomic force microscopy, a method previously used to study the crystallization of annexin A5, to image the effects of monoclonal human aPL antibodies on the crystal structure of the protein over phospholipid bilayers. In the presence of the aPL monoclonal antibodies (mAbs) and β2-GPI, the major aPL co-factor, structures presumed to be aPL mAb-antigen complexes were associated with varying degrees of disruption to the annexin A5 crystallization pattern over the bilayer. In addition, measurements of prothrombinase activity on the phospholipid bilayers showed that the aPL mAbs reduced the anti-coagulant effect of annexin A5 and promoted thrombin generation. These data provide morphological evidence that support the hypothesis that aPL antibodies can disrupt annexin A5 binding to phospholipid membranes and permit increased generation of thrombin. The aPL antibody-mediated disruption of the annexin A5 anticoagulant shield may be an important prothrombotic mechanism in the aPL syndrome. PMID:12937161

  12. Activated protein C modulates the proinflammatory activity of dendritic cells

    Directory of Open Access Journals (Sweden)

    Matsumoto T

    2015-05-01

    Full Text Available Takahiro Matsumoto,1,2* Yuki Matsushima,1* Masaaki Toda,1 Ziaurahman Roeen,1 Corina N D'Alessandro-Gabazza,1,5 Josephine A Hinneh,1 Etsuko Harada,1,3 Taro Yasuma,4 Yutaka Yano,4 Masahito Urawa,1,5 Tetsu Kobayashi,5 Osamu Taguchi,5 Esteban C Gabazza1 1Department of Immunology, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, 2BONAC Corporation, BIO Factory 4F, Fukuoka, 3Iwade Research Institute of Mycology, 4Department of Endocrinology, Diabetes and Metabolism, 5Department of Pulmonary and Critical Care Medicine, Mie University Graduate School of Medicine, Tsu, Mie Prefecture, Japan *These authors contributed equally to this work Background: Previous studies have demonstrated the beneficial activity of activated protein C in allergic diseases including bronchial asthma and rhinitis. However, the exact mechanism of action of activated protein C in allergies is unclear. In this study, we hypothesized that pharmacological doses of activated protein C can modulate allergic inflammation by inhibiting dendritic cells. Materials and methods: Dendritic cells were prepared using murine bone marrow progenitor cells and human peripheral monocytes. Bronchial asthma was induced in mice that received intratracheal instillation of ovalbumin-pulsed dendritic cells. Results: Activated protein C significantly increased the differentiation of tolerogenic plasmacytoid dendritic cells and the secretion of type I interferons, but it significantly reduced lipopolysaccharide-mediated maturation and the secretion of inflammatory cytokines in myeloid dendritic cells. Activated protein C also inhibited maturation and the secretion of inflammatory cytokines in monocyte-derived dendritic cells. Activated protein C-treated dendritic cells were less effective when differentiating naïve CD4 T-cells from Th1 or Th2 cells, and the cellular effect of activated protein C was mediated by its receptors. Mice that received adoptive transfer of activated protein C

  13. To anticoagulate or not to anticoagulate patients with cardiomyopathy.

    Science.gov (United States)

    Graham, S P

    2001-11-01

    The current published literature does not indicate whether the long-term effect of anticoagulant or antiplatelet therapy contributes to mortality reduction in patients with LV dysfunction. Evaluating patients for personal risk for emboli or for ischemic coronary artery events may influence the choice of therapies. As more is learned about the mechanisms of drug effects in different populations, physicians may be better able to direct appropriate therapies. Until that time, one must weigh the risks and benefits of each drug alone and in combination. In NYHA class IV patients, the risk for thrombosis owing to spontaneous clotting increases as does the adverse potential of warfarin and the adverse effects of inhibiting prostaglandin mediated vasodilation by aspirin. In NYHA class I and II patients, the quality of life and convenience of multidrug therapy is weighed against the devastating effect of a major stroke. In less symptomatic patients, the long-term risk for acute coronary events may be higher than previously identified. This would suggest that all patients with depressed LV function should be on some type of antiplatelet or anticoagulant therapy. The current WATCH study will provide much needed information about the outcome differences between these agents. Conclusions based on available data include the following: Heart failure is increasing in incidence and prevalence. Atherosclerotic disease is an important causative factor for the development of heart failure or may be a comorbid condition in these patients. There is a measurable rate of stroke in patients with heart failure, although the cause of death in large studies is more often owing to sudden death or progressive heart failure. Sudden death may be from new ischemic events, asystole, or from ventricular tachyarrhythmias. In patients with heart failure, not all strokes are cardioembolic in origin. The benefits and risks of warfarin may be increased as the EF worsens or heart failure functional class

  14. Tailoring the surface properties of polypropylene films through cold atmospheric pressure plasma (CAPP) assisted polymerization and immobilization of biomolecules for enhancement of anti-coagulation activity

    Science.gov (United States)

    Navaneetha Pandiyaraj, K.; Ram Kumar, M. C.; Arun Kumar, A.; Padmanabhan, P. V. A.; Deshmukh, R. R.; Bah, M.; Ismat Shah, S.; Su, Pi-Guey; Halleluyah, M.; Halim, A. S.

    2016-05-01

    Enhancement of anti-thrombogenic properties of polypropylene (PP) to avert the adsorption of plasma proteins (fibrinogen and albumin), adhesion and activation of the platelets are very important for vast biomedical applications. The cold atmospheric pressure plasma (CAPP) assisted polymerization has potential to create the specific functional groups such as Osbnd Cdbnd O, Cdbnd O, Csbnd N and Ssbnd S. on the surface of polymeric films using selective precursor in vapour phase to enhance anti-thrombogenic properties. Such functionalized polymeric surfaces would be suitable for various biomedical applications especially to improve the blood compatibility. The eventual aspiration of the present investigation is to develop the biofunctional coating onto the surface of PP films using acrylic acid (AAc) and polyethylene glycol (PEG) as a precursor in a vapour phase by incorporating specific functional groups for immobilization of biomolecules such as heparin (HEP), chitosan (CHI) and insulin (INS) on the surface of plasma modified PP films. The surface properties such as hydrophilicity, chemical composition, surface topography of the surface modified PP films were analyzed by contact angle (CA), Fourier transform infrared spectroscopy (FTIR), X-ray photo electron spectroscopy (XPS) and atomic force microscopy (AFM). Furthermore the anti-thrombogenic properties of the surface modified PP films were studied by in vitro tests which include platelet adhesion and protein adsorption analysis. It was found that the anti-thrombogenic properties of the PP films are effectively controlled by the CAPP grafting of AAc and PEG followed by immobilization of biomolecules of heparin, chitosan and insulin. The grafting and immobilization was confirmed by FTIR and XPS through the recognition of specific functional groups such as COOH, Csbnd O, Ssbnd S and Csbnd N. on the surface of PP film. Furthermore, the surface morphology and hydrophilic nature of the PP films also tailored

  15. Anticoagulants

    Science.gov (United States)

    ... even if it is not listed below. Aspirin Acetaminophen (e.g., Tylenol, Excedrin) Ibuprofen (e.g., Motrin, ... skin or eyes (jaundice) Rare side effects: Headache Dizziness Shortness of breath Mouth sores or bleeding gums ...

  16. Activated protein C inhibits neutrophil migration in allergic asthma: a randomised trial.

    Science.gov (United States)

    de Boer, J Daan; Berger, Marieke; Majoor, Christof J; Kager, Liesbeth M; Meijers, Joost C M; Terpstra, Sanne; Nieuwland, Rienk; Boing, Anita N; Lutter, René; Wouters, Diana; van Mierlo, Gerard J; Zeerleder, Sacha S; Bel, Elisabeth H; van't Veer, Cornelis; de Vos, Alex F; van der Zee, Jaring S; van der Poll, Tom

    2015-12-01

    Asthma patients show evidence of a procoagulant state in their airways, accompanied by an impaired function of the anticoagulant protein C system. We aimed to study the effect of recombinant human activated protein C (rhAPC) in allergic asthma patients.We conducted a randomised, double-blind, placebo-controlled, proof-of-concept study in house dust mite (HDM) allergic asthma patients. Patients were randomised to receive intravenous rhAPC (24 µg·kg(-1)·h(-1); n=12) or placebo (n=12) for 11 h. 4 h after the start of infusion, a first bronchoscopy was performed to challenge one lung segment with saline (control) and a contralateral segment with a combination of HDM extract and lipopolysaccharide (HDM+LPS), thereby mimicking environmental house dust exposure. A second bronchoscopy was conducted 8 h after intrabronchial challenge to obtain bronchoalveolar lavage fluid (BALF).rhAPC did not influence HDM+LPS induced procoagulant changes in the lung. In contrast, rhAPC reduced BALF leukocyte counts by 43% relative to placebo, caused by an inhibitory effect on neutrophil influx (64% reduction), while leaving eosinophil influx unaltered. rhAPC also reduced neutrophil degranulation products in the airways.Intravenous rhAPC attenuates HDM+LPS-induced neutrophil migration and protein release in allergic asthma patients by an effect that does not rely on coagulation inhibition. PMID:26381519

  17. Dose Dependence of the Anticoagulant Effect of Intravenously Administered Cellulose Sulfate.

    Science.gov (United States)

    Drozd, N N; Kuznetsova, S A; Kalinina, T B; Vasilieva, N Yu

    2016-04-01

    Experiments on rabbits showed that increasing the dose of intravenously administered cellulose sulfate from wheat straw (dynamic viscosity 3.4 cP, sulfur content 14.1%) increased plasma clotting time in some coagulation tests and plasma anticoagulant activity. When cellulose sulfate was administered in the dose of 1 mg/kg, plasma clotting time in the presence of the anticoagulant (5 min after administration) was ~3-fold higher than after saline administration. PMID:27165079

  18. Momordica charantia seed extract exhibits strong anticoagulant effect by specifically interfering in intrinsic pathway of blood coagulation and dissolves fibrin clot.

    Science.gov (United States)

    Manjappa, Bhagyalakshmi; Gangaraju, Sowmyashree; Girish, Kesturu S; Kemparaju, Kempaiah; Gonchigar, Sathish J; Shankar, Rohit L; Shinde, Manohar; Sannaningaiah, Devaraja

    2015-03-01

    The current study explores the anticoagulant and fibrin clot-hydrolyzing properties of Momordica charantia seed extract (MCSE). MCSE hydrolyzed casein with the specific activity of 0.780 units/mg per min. Interestingly, it enhanced the clot formation process of citrated human plasma from control 146 to 432 s. In addition, the intravenous injection of MCSE significantly prolonged the bleeding time in a dose-dependent manner from control 150 to more than 800 s, and strengthened its anticoagulant activity. Interestingly, MCSE specifically prolonged the clotting time of only activated partial thromboplastin time, but not prothrombin time, and revealed the participation of MCSE in the intrinsic pathway of the blood coagulation cascade. Furthermore, MCSE completely hydrolyzed both Aα and Bβ chains of the human fibrinogen and partially hydrolyzed the γ chain. However, it hydrolyzed all the chains (α polymer, α chain, β chain and γ-γ dimmers) of partially cross-linked human fibrin clot. The proteolytic activity followed by the anticoagulant effect of the MCSE was completely abolished by the 1,10-phenanthroline and phenyl methyl sulphonyl fluoride, but iodoacetic acid, EDTA, and ethylene glycol-N,N,N',N'-tetra acetic acid did not. Curiously, MCSE did not hydrolyze any other plasma proteins except the plasma fibrinogen. Moreover, MCSE was devoid of RBC lysis, edema and hemorrhagic properties, suggesting its nontoxic nature. Taken together, MCSE may be a valuable candidate in the treatment of blood clot/thrombotic disorders. PMID:25192240

  19. Chitosan-based ultrathin films as antifouling, anticoagulant and antibacterial protective coatings.

    Science.gov (United States)

    Bulwan, Maria; Wójcik, Kinga; Zapotoczny, Szczepan; Nowakowska, Maria

    2012-01-01

    Ultrathin antifouling and antibacterial protective nanocoatings were prepared from ionic derivatives of chitosan using layer-by-layer deposition methodology. The surfaces of silicon, and glass protected by these nanocoatings were resistant to non-specific adsorption of proteins disregarding their net charges at physiological conditions (positively charged TGF-β1 growth factor and negatively charged bovine serum albumin) as well as human plasma components. The coatings also preserved surfaces from the formation of bacterial (Staphylococcus aureus) biofilm as shown using microscopic studies (SEM, AFM) and the MTT viability test. Moreover, the chitosan-based films adsorbed onto glass surface demonstrated the anticoagulant activity towards the human blood. The antifouling and antibacterial actions of the coatings were correlated with their physicochemical properties. The studied biologically relevant properties were also found to be dependent on the thickness of those nanocoatings. These materials are promising for biomedical applications, e.g., as protective coatings for medical devices, anticoagulant coatings and protective layers in membranes. PMID:21967904

  20. Compatibility of Injectable Anticoagulant Agents in Ethanol; In Vitro Antibiofilm Activity and Impact on Polyurethane Catheters of Enoxaparin 400 U/mL in 40% v/v Ethanol

    Science.gov (United States)

    Charbonnel, Nicolas; Forestier, Christiane; Lartigue, Claire; Souweine, Bertrand

    2016-01-01

    Background and Objectives Interdialytic lock solutions should maintain catheter patency and prevent catheter infections. We aimed to determine in which conditions injectable anticoagulant agents (IAAs) combined with ethanol are compatible and to assess the antibiofilm activity of the selected combination and its effects on dialysis catheters (DC). Methods The solubility and compatibility of unfractionated heparin (UFH), low molecular weight heparins (LMWHs), heparinoids and fondaparinux (50 to 2,500 U/mL) in 30 to 70% ethanol were determined by visual observation. The stability of enoxaparin in ethanol and the ethanol content were assessed by high performance liquid chromatography (HPLC) and titrimetric control, respectively. The bactericidal effect was determined on 24h-old biofilms embedded in silicone-DC. The integrity of polyurethane-DC immersed in anticoagulant-ethanol was assessed by gas chromatography-mass spectrometry (GC-MS) and compared with previously published results. Results The compatibility of IAAs and ethanol varied according to IAA type and concentration, and ethanol content. UFH in 40% ethanol was not compatible, whatever the UFH concentration used. Established limits of compatibility of enoxaparin, nadroparin, dalteparin and tinzaparin in 40% ethanol were 1350, 575, 307 and 207 U/ml, respectively, and up to 300 U/ml for danaparoid and 1 mg/mL for fondaparinux. Enoxaparin 400 U/mL in 40% ethanol (Enox/Eth) eradicated biofilm after 4 hours of exposure for Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans and after 24 hours for Klebsiella pneumoniae and S. aureus. Aliphatic carbonate and alcohol compounds were released by polyurethane-DC after Enox/Eth exposure, as after 40% ethanol or saline exposure. There was no significant difference between the amounts released after 30 minutes of exposure to Enox/Eth and 15 days to saline. Conclusions A 40% ethanol solution can be combined with all IAAs but UFH. Enox/Eth was effective as

  1. Bleeding Risk, Management and Outcome in Patients Receiving Non-VKA Oral Anticoagulants (NOACs).

    Science.gov (United States)

    Werth, Sebastian; Breslin, Tomás; NiAinle, Fionnuala; Beyer-Westendorf, Jan

    2015-08-01

    Modern direct-acting anticoagulants are rapidly replacing vitamin K antagonists (VKA) in the management of millions of patients worldwide who require anticoagulation. These drugs include agents that inhibit activated factor X (FXa) (such as apixaban and rivaroxaban) or thrombin (such as dabigatran), and are collectively known today as non-VKA oral anticoagulants (NOACs). Since bleeding is the most common and most dangerous side effect of long-term anticoagulation, and because NOACs have very different mechanisms of action and pharmacokinetics compared with VKA, physicians are naturally concerned about the lack of experience regarding frequency, management and outcome of NOAC-associated bleeding in daily care. This review appraises trial and registry (or "real-world") data pertaining to bleeding complications in patients taking NOACs and VKA and provides practical recommendations for the management of acute bleeding situations. PMID:25940651

  2. Activation and activities of the p53 tumour suppressor protein

    OpenAIRE

    Bálint, É; Vousden, K H

    2001-01-01

    The p53 tumour suppressor protein inhibits malignant progression by mediating cell cycle arrest, apoptosis or repair following cellular stress. One of the major regulators of p53 function is the MDM2 protein, and multiple forms of cellular stress activate p53 by inhibiting the MDM2-mediated degradation of p53. Mutations in p53, or disruption of the pathways that allow activation of p53, seem to be a general feature of all cancers. Here we review recent advances in our understanding of the pat...

  3. Honey Bee Venom (Apis mellifera Contains Anticoagulation Factors and Increases the Blood-clotting Time

    Directory of Open Access Journals (Sweden)

    Hossein Zolfagharian

    2015-12-01

    Full Text Available Objectives: Bee venom (BV is a complex mixture of proteins and contains proteins such as phospholipase and melittin, which have an effect on blood clotting and blood clots. The mechanism of action of honey bee venom (HBV, Apis mellifera on human plasma proteins and its anti-thrombotic effect were studied. The purpose of this study was to investigate the anti-coagulation effect of BV and its effects on blood coagulation and purification. Methods: Crude venom obtained from Apis mellifera was selected. The anti-coagulation factor of the crude venom from this species was purified by using gel filtration chromatography (sephadex G-50, and the molecular weights of the anti-coagulants in this venom estimated by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. Blood samples were obtained from 10 rabbits, and the prothrombin time (PT and the partial thromboplastin time (PTT tests were conducted. The approximate lethal dose (LD values of BV were determined. Results: Crude BV increased the blood clotting time. For BV concentrations from 1 to 4 mg/mL, clotting was not observed even at more than 300 seconds, standard deviations (SDs = ± 0.71; however, clotting was observed in the control group 13.8 s, SDs = ± 0.52. Thus, BV can be considered as containing anti-coagulation factors. Crude BV is composed 4 protein bands with molecular weights of 3, 15, 20 and 41 kilodalton (kDa, respectively. The LD50 of the crude BV was found to be 177.8 μg/mouse. Conclusion: BV contains anti-coagulation factors. The fraction extracted from the Iranian bees contains proteins that are similar to anti-coagulation proteins, such as phospholipase A2 (PLA2 and melittin, and that can increase the blood clotting times in vitro.

  4. Total Cellular RNA Modulates Protein Activity.

    Science.gov (United States)

    Majumder, Subhabrata; DeMott, Christopher M; Reverdatto, Sergey; Burz, David S; Shekhtman, Alexander

    2016-08-16

    RNA constitutes up to 20% of a cell's dry weight, corresponding to ∼20 mg/mL. This high concentration of RNA facilitates low-affinity protein-RNA quinary interactions, which may play an important role in facilitating and regulating biological processes. In the yeast Pichia pastoris, the level of ubiquitin-RNA colocalization increases when cells are grown in the presence of dextrose and methanol instead of methanol as the sole carbon source. Total RNA isolated from cells grown in methanol increases β-galactosidase activity relative to that seen with RNA isolated from cells grown in the presence of dextrose and methanol. Because the total cellular RNA content changes with growth medium, protein-RNA quinary interactions can alter in-cell protein biochemistry and may play an important role in cell adaptation, critical to many physiological and pathological states. PMID:27456029

  5. Raman optical activity of proteins and glycoproteins

    International Nuclear Information System (INIS)

    Raman optical activity (ROA), measured in this project as a small difference in the intensity of Raman scattering from chiral molecules in right- and left-circularly polarised incident laser light, offers the potential to provide more information about the structure of biological molecules in aqueous solution than conventional spectroscopic techniques. Chapter one contains a general discussion of the relative merits of different spectroscopic techniques for structure determination of biomolecules, as well as a brief introduction to ROA. In Chapter two a theoretical analysis of ROA is developed, which extends the discussion in chapter one. The spectrometer setup and sample preparation is then discussed in chapter three. Instrument and sample conditions are monitored to ensure that the best results are obtained. As with any experimental project problems occur, which may result in a degradation of the spectra obtained. The cause of these problems was explored and remedied whenever possible. Chapter four introduces a brief account of protein, glycoprotein and carbohydrate structure and function, with a particular emphasis on the structure of proteins. In the remaining chapters experimental ROA results on proteins and glycoproteins, with some carbohydrate samples, from a wide range of sources are examined. For example, in chapter five some β-sheet proteins are examined. Structural features in these proteins are examined in the extended amide III region of their ROA spectra, revealing that ROA is sensitive to the rigidity or flexibility inherent in proteins. Chapter six concentrates on a group of proteins (usually glycoproteins) known as the serine proteinase inhibitors (serpins). Medically, the serpins are one of the most important groups of proteins of current interest, with wide-ranging implications in conditions such as Down's syndrome, Alzheimer's disease, and emphysema with associated cirrhosis of the liver. With favourable samples and conditions ROA may offer the

  6. Mitogen-activated protein kinases in atherosclerosis

    Directory of Open Access Journals (Sweden)

    Dorota Bryk

    2014-01-01

    Full Text Available Intracellular signalling cascades, in which MAPK (mitogen-activated protein kinases intermediate, are responsible for a biological response of a cell to an external stimulus. MAP kinases, which include ERK1/2 (extracellular signalling-regulated kinase, JNK (c-Jun N-terminal kinase and p 38 MAPK, regulate the activity of many proteins, enzymes and transcription factors and thus have a wide spectrum of biological effects. Many basic scientific studies have defined numerous details of their pathway organization and activation. There are also more and more studies suggesting that individual MAP kinases probably play an important role in the pathogenesis of atherosclerosis. They may mediate inflammatory processes, endothelial cell activation, monocyte/macrophage recruitment and activation, smooth muscle cell proliferation and T-lymphocyte differentiation, all of which represent crucial mechanisms involved in pathogenesis of atherosclerosis. The specific inhibition of an activity of the respective MAP kinases may prove a new therapeutic approach to attenuate atherosclerotic plaque formation in the future. In this paper, we review the current state of knowledge concerning MAP kinase-dependent cellular and molecular mechanisms underlying atherosclerosis.

  7. [Mitogen-activated protein kinases in atherosclerosis].

    Science.gov (United States)

    Bryk, Dorota; Olejarz, Wioletta; Zapolska-Downar, Danuta

    2014-01-01

    Intracellular signalling cascades, in which MAPK (mitogen-activated protein kinases) intermediate, are responsible for a biological response of a cell to an external stimulus. MAP kinases, which include ERK1/2 (extracellular signalling-regulated kinase), JNK (c-Jun N-terminal kinase) and p 38 MAPK, regulate the activity of many proteins, enzymes and transcription factors and thus have a wide spectrum of biological effects. Many basic scientific studies have defined numerous details of their pathway organization and activation. There are also more and more studies suggesting that individual MAP kinases probably play an important role in the pathogenesis of atherosclerosis. They may mediate inflammatory processes, endothelial cell activation, monocyte/macrophage recruitment and activation, smooth muscle cell proliferation and T-lymphocyte differentiation, all of which represent crucial mechanisms involved in pathogenesis of atherosclerosis. The specific inhibition of an activity of the respective MAP kinases may prove a new therapeutic approach to attenuate atherosclerotic plaque formation in the future. In this paper, we review the current state of knowledge concerning MAP kinase-dependent cellular and molecular mechanisms underlying atherosclerosis. PMID:24491891

  8. Synaptic Vesicle Proteins and Active Zone Plasticity

    Science.gov (United States)

    Kittel, Robert J.; Heckmann, Manfred

    2016-01-01

    Neurotransmitter is released from synaptic vesicles at the highly specialized presynaptic active zone (AZ). The complex molecular architecture of AZs mediates the speed, precision and plasticity of synaptic transmission. Importantly, structural and functional properties of AZs vary significantly, even for a given connection. Thus, there appear to be distinct AZ states, which fundamentally influence neuronal communication by controlling the positioning and release of synaptic vesicles. Vice versa, recent evidence has revealed that synaptic vesicle components also modulate organizational states of the AZ. The protein-rich cytomatrix at the active zone (CAZ) provides a structural platform for molecular interactions guiding vesicle exocytosis. Studies in Drosophila have now demonstrated that the vesicle proteins Synaptotagmin-1 (Syt1) and Rab3 also regulate glutamate release by shaping differentiation of the CAZ ultrastructure. We review these unexpected findings and discuss mechanistic interpretations of the reciprocal relationship between synaptic vesicles and AZ states, which has heretofore received little attention.

  9. [Antioxidant activity of cationic whey protein isolate].

    Science.gov (United States)

    titova, M E; Komolov, S A; Tikhomirova, N A

    2012-01-01

    The process of lipid peroxidation (LPO) in biological membranes of cells is carried out by free radical mechanism, a feature of which is the interaction of radicals with other molecules. In this work we investigated the antioxidant activity of cationic whey protein isolate, obtained by the cation-exchange chromatography on KM-cellulose from raw cow's milk, in vitro and in vivo. In biological liquids, which are milk, blood serum, fetal fluids, contains a complex of biologically active substances with a unique multifunctional properties, and which are carrying out a protective, antimicrobial, regenerating, antioxidant, immunomodulatory, regulatory and others functions. Contents of the isolate were determined electrophoretically and by its biological activity. Cationic whey protein isolate included lactoperoxidase, lactoferrin, pancreatic RNase, lysozyme and angeogenin. The given isolate significantly has an antioxidant effect in model experimental systems in vitro and therefore may be considered as a factor that can adjust the intensity of lipid oxidation. In model solutions products of lipid oxidation were obtained by oxidation of phosphatidylcholine by hydrogen peroxide in the presence of a source of iron. The composition of the reaction mixture: 0,4 mM H2O2; 50 mcM of hemin; 2 mg/ml L-alpha-phosphatidylcholine from soybean (Sigma, German). Lipid peroxidation products were formed during the incubation of the reaction mixture for two hours at 37 degrees C. In our studies rats in the adaptation period immediately after isolation from the nest obtained from food given orally native cationic whey protein isolate at the concentration three times higher than in fresh cow's milk. On the manifestation of the antioxidant activity of cationic whey protein isolate in vivo evidence decrease of lipid peroxidation products concentration in the blood of rats from the experimental group receipt whey protein isolate in dos 0,6 mg/g for more than 20% (pwhey protein isolate has an

  10. D-dimer: a useful tool in gauging optimal duration of oral anticoagulant therapy?

    Directory of Open Access Journals (Sweden)

    M. Silingardi

    2013-05-01

    Full Text Available BACKGROUND AND AIM OF THE STUDY Optimal duration of oral anticoagulant therapy (OAT in idiopathic venous thromboembolism (VTE is unknown. Indefinite OAT carries an unacceptable risk of major bleeding and prospective studies have demonstrated that OAT is no longer protective after its withdrawal. How to identify the patients at risk for recurrence? D-dimer is a marker of thrombin activity. Early prospective studies showed that elevated D-dimer levels after anticoagulation had a highly predictive value for a recurrent episode. Does D-dimer assay have a role in gauging the appropriate duration of anticoagulant therapy? The PROLONG study tries to answer this question. METHOD D-dimer assay was performed one month after stopping anticoagulation. Patiens with normal D-dimer levels did not resume anticoagulation while patients with elevated D-dimer levels were randomized to discontinue or resume anticoagulation. Study end-points was the composite of recurrent VTE and major bleeding during an average follow-up of 1.4 years. RESULTS The rate of recurrence is significantly higher in patients with elevated D-dimer levels who discontinued anticoagulation. Resuming anticoagulation in this cohort of patients markedly reduces recurrent events without increasing major bleeding. DISCUSSION AND CONCLUSIONS PROLONG study is provocative, because D-dimer assay is simple, thus not requiring dedicated laboratory facilities. D-dimer test has otherwise high sensitivity but low specificity in VTE diagnosis. Aspecifically elevated D-dimer levels are available in the elderly and the majority of patients included in the study were > 65 years old, thus introducing a possible selection bias. Nonetheless the results of the study are useful for the clinician. Prolongation of vitamin K antagonists in patients with elevated D-dimer levels one month after discontinuation of OAT for a first unprovoked episode of VTE results in a favourable risk-benefit relationship. Probably this

  11. Occurrence, elimination, and risk of anticoagulant rodenticides and drugs during wastewater treatment.

    Science.gov (United States)

    Gómez-Canela, Cristian; Barata, Carlos; Lacorte, Silvia

    2014-01-01

    Anticoagulants are biocides widely used as pest control agents in agriculture, urban infrastructures, and domestic applications for the control of rodents. Other anticoagulants such as warfarin and acenocoumarol are also used as drugs against thrombosis. After use, anticoagulants are discharged to sewage grids and enter wastewater treatment plants (WWTPs). Our hypothesis is that WWTP effluents can be a source of anticoagulants to receiving waters and that these can affect aquatic organisms and other nontarget species. Therefore, the objective of the present study was to determine the occurrence of 11 anticoagulants in WWTPs receiving urban and agricultural wastewaters. Warfarin was the most ubiquitous compound detected in influent waters and was partially eliminated during the activated sludge treatment, and low nanograms per liter concentration were found in the effluents. Other detected compounds were coumatetralyl, ferulenol, acenocoumarol, flocoumafen, brodifacoum, bromadiolone, and difenacoum at concentrations of 0.86-87.0 ng L(-1). Considering water volumes of each WWTP, daily emissions were estimated to be 0.02 to 21.8 g day(-1), and thus, WWTPs contribute to the loads of anticoagulants to receiving waters. However, low aquatic toxicity was observed using Daphnia magna as a model aquatic organism. PMID:24622989

  12. Protein C activators in snake venoms.

    Science.gov (United States)

    Stocker, K; Fischer, H; Meier, J; Brogli, M; Svendsen, L

    1986-02-01

    Venoms of 32 snake species were tested for protein C (PC) activating potency. As measured with the chromogenic PC substrate D-Pro-L-Pro-L-Arg-pNA, eleven venoms were able to generate amidolytic activity from purified bovine PC. In five venom solutions (Bothrops moojeni, B. pradoi, Cerastes cerastes, Vipera lebetina and V. russellii) the PC activating potency was destroyed during 10 min heating at 70 degrees C at pH 3, whereas in six venom solutions (Agkistrodon contortrix contortrix, A. c. mokasen, A. c. pictigaster, Agkistrodon piscivorus, A. p. leucostoma and A. bilineatus) the PC activator was stable under these conditions. PC activator from A. c. contortrix (Protac) was purified to homogeneity and characterized as a single chain polypeptide with a molecular weight of approx. 39-42,000 Dalton. Protac does not exert proteinase activity and is not inhibited by proteinase inhibitors; PC activation with Protac seems to be a stoichiometric reaction. The use of Protac in quantitative PC determination bears significant advantages over the use of thrombin as an activator. In rabbits, i.v. injection of Protac caused a prolonged APTT and did not provoke acute toxic reactions. PMID:3755037

  13. Pilot-Scale Fermentation Study of a Low Bleeding Anticoagulant Protein in Pichia pastoris%重组低出血抗凝蛋白在毕赤酵母中的中试发酵工艺研究及其纯化与鉴定

    Institute of Scientific and Technical Information of China (English)

    郝木强; 李彦英; 刘春杰; 王秀冬; 刘晶晶; 李艳琪; 刘洋; 吴祖泽; 靳继德

    2013-01-01

      Objective: To establish a practical method of pilot-scale yeast fermentation for the production of a low bleeding anticoagulant protein recombinant-EPR-hirudin(EH). Methods:The growth curve of recombinant Pi⁃chia pastoris secreting EH in shake flask cultivation was determined. Then, according to the determined growth curve, strains were amplified by two shake flask cultures and were directly inoculated into fermentation broth of 500 L. The fermentation was dynamically monitored by the dissolved oxygen and absorbance in 600 nm of the broth, and the wet weight of the strains as well. The target protein expression was induced with methanol feeding. After fermentation, the target proteins were purified through ultrafiltration and a two-step ion-exchange chromatogra⁃phy. The purity of target proteins was analyzed by SDS-PAGE and HPLC, and the molecular weight was exam⁃ined by reducing SDS-PAGE and mass spectrometry. Furthermore, EH was identified by Western blotting, and its anticoagulant activity was analyzed by a clot method. Results: After direct inoculation from flask cultivation, the re⁃combinant engineering yeasts grew well in a fermenter of 500 L tank volume. The total protein content of fermenta⁃tion supernatants was 1.41 g/L at the end of the fermentation. After separation and purification, 21 g of EH pro⁃tein was obtained. The results of the non-reducing SDS-PAGE and HPLC analysis showed that the purity of EH was more than 95%. The relative molecular weight of EH was about 7.3±0.73 kD determined by mass spectrome⁃ try analysis, however, displayed about 13.2±0.2 kD under the SDS-PAGE analysis. The result of Western blotting indicated that the EH protein can be recognized by the commercial mouse anti-hirudin antibody. Moreover, the an⁃ti-thrombin activity of EH protein was about 512~1024 ATU/mg after incubation with bovine coagulation factor Xa. Conclusion: We have developed a simple and convenient method of pilot-scale yeast fermentation

  14. Human monoclonal antiphospholipid antibodies disrupt the annexin A5 anticoagulant crystal shield on phospholipid bilayers: evidence from atomic force microscopy and functional assay.

    Science.gov (United States)

    Rand, Jacob H; Wu, Xiao-Xuan; Quinn, Anthony S; Chen, Pojen P; McCrae, Keith R; Bovill, Edwin G; Taatjes, Douglas J

    2003-09-01

    The antiphospholipid (aPL) syndrome is an autoimmune condition that is marked by recurrent pregnancy losses and/or systemic vascular thrombosis in patients who have antibodies against phospholipid/co-factor complexes. The mechanism(s) for pregnancy losses and thrombosis in this condition is (are) not known. Annexin A5 is a potent anticoagulant protein, expressed by placental trophoblasts and endothelial cells, that crystallizes over anionic phospholipids, shielding them from availability for coagulation reactions. We previously presented data supporting the hypothesis that aPL antibody-mediated disruption of the anticoagulant annexin A5 shield could be a thrombogenic mechanism in the aPL syndrome. However, this has remained a subject of controversy. We therefore used atomic force microscopy, a method previously used to study the crystallization of annexin A5, to image the effects of monoclonal human aPL antibodies on the crystal structure of the protein over phospholipid bilayers. In the presence of the aPL monoclonal antibodies (mAbs) and beta(2)-GPI, the major aPL co-factor, structures presumed to be aPL mAb-antigen complexes were associated with varying degrees of disruption to the annexin A5 crystallization pattern over the bilayer. In addition, measurements of prothrombinase activity on the phospholipid bilayers showed that the aPL mAbs reduced the anti-coagulant effect of annexin A5 and promoted thrombin generation. These data provide morphological evidence that support the hypothesis that aPL antibodies can disrupt annexin A5 binding to phospholipid membranes and permit increased generation of thrombin. The aPL antibody-mediated disruption of the annexin A5 anticoagulant shield may be an important prothrombotic mechanism in the aPL syndrome. PMID:12937161

  15. Specific antidotes against direct oral anticoagulants: A comprehensive review of clinical trials data.

    Science.gov (United States)

    Tummala, Ramyashree; Kavtaradze, Ana; Gupta, Anjan; Ghosh, Raktim Kumar

    2016-07-01

    The Vitamin K antagonist warfarin was the only oral anticoagulant available for decades for the treatment of thrombosis and prevention of thromboembolism until Direct Oral Anticoagulants (DOACs); a group of new oral anticoagulants got approved in the last few years. Direct thrombin inhibitor: dabigatran and factor Xa inhibitors: apixaban, rivaroxaban, and edoxaban directly inhibit the coagulation cascade. DOACs have many advantages over warfarin. However, the biggest drawback of DOACs has been the lack of specific antidotes to reverse the anticoagulant effect in emergency situations. Activated charcoal, hemodialysis, and activated Prothrombin Complex Concentrate (PCC) were amongst the nonspecific agents used in a DOAC associated bleeding but with limited success. Idarucizumab, the first novel antidote against direct thrombin inhibitor dabigatran was approved by US FDA in October 2015. It comprehensively reversed dabigatran-induced anticoagulation in a phase I study. A phase III trial on Idarucizumab also complete reversal of anticoagulant effect of dabigatran. Andexanet alfa (PRT064445), a specific reversal agent against factor Xa inhibitors, showed a complete reversal of anticoagulant activity of apixaban and rivaroxaban within minutes after administration without adverse effects in two recently completed parallel phase III trials ANNEXA-A and ANNEXA-R respectively. It is currently being studied in ANNEXA-4, a phase IV study. Aripazine (PER-977), the third reversal agent, has shown promising activity against dabigatran, apixaban, rivaroxaban, as well as subcutaneous fondaparinux and LMWH. This review article summarizes pharmacological characteristics of these novel antidotes, coagulation's tests affected, available clinical and preclinical data, and the need for phase III and IV studies. PMID:27082776

  16. Direct oral anticoagulants: a guide for daily practice.

    Science.gov (United States)

    Fontana, Pierre; Robert-Ebadi, Helia; Bounameaux, Henri; Boehlen, Françoise; Righini, Marc

    2016-01-01

    In recent years, small oral compounds that specifically block activated coagulation factor X (FXa) or thrombin (FIIa) have become alternatives to the anticoagulants that had been used for several decades. As of today, these direct oral anticoagulants (DOACs) include dabigatran etexilate (thrombin inhibitor) and apixaban, edoxaban and rivaroxaban (inhibitors of FXa). While there is no doubt that DOACs represent a major step forward in the management of patients with venous thromboembolic disease and atrial fibrillation, new challenges have arisen. They need to be addressed with the necessary pragmatism on the basis of evidence. Indeed, a better understanding of the management of these last-generation antithrombotics will favour safer use and increase confidence of the practitioner for the prescription of these drugs. The aim of this article is to present practical suggestions for the prescription and use of these drugs in everyday clinical practice, based on clinical experience and recently updated recommendations of the European Heart Rhythm Association and the American College of Chest Physicians among other scientific organisations. We address issues such as pharmacokinetics, dosing, side effects, limitations of use, drug interactions, switching from and to other anticoagulants, renal function, concomitant administration of antiplatelet agents and perioperative use. We also address the issue of monitoring and reversal, taking advantage of the most recent development in this latter area. Rather than being one additional set of recommendations, our narrative review aims at assisting the practicing physician in his or her daily handling of these novel anticoagulant compounds, based on frequently asked questions to the authors, a group of experienced specialists in the field who have, however, no commitment to issue guidelines. PMID:26964028

  17. Novel oral anticoagulants for heparin-induced thrombocytopenia.

    Science.gov (United States)

    Skelley, Jessica W; Kyle, Jeffrey A; Roberts, Rachel A

    2016-08-01

    To review the use of the novel oral anticoagulant (NOAC) agents for the treatment of heparin-induced thrombocytopenia (HIT) from relevant clinical trial data. A MEDLINE, International Pharmaceutical Abstracts, ClinicalTrials.gov, and Google-Scholar searches (1966-March 2016) were conducted using the keywords: thrombocytopenia, NOACs, dabigatran, apixaban, rivaroxaban, edoxaban, Xa inhibitor, direct thrombin inhibitor. Articles evaluating the new oral anticoagulants for thrombocytopenia published in English and using human subjects were selected. Eight clinical trials were identified. References cited in identified articles were used for additional citations. Approximately 12 million hospitalized patients each year are exposed to heparin for thromboprophylaxis. HIT, an immune-mediated, prothrombotic adverse reaction is a potential complication of heparin therapy. As a result, heparin products must be immediately withdrawn and replaced by alternative anticoagulants to compensate for the thrombotic risk associated with HIT. Limitations exist with the only currently FDA approved heparin alternative, argatroban. NOACs have been considered as potential alternatives to traditional agents based on their pharmacologic activity. Case reports have indicated positive results in patients, with clinical outcomes and tolerability supporting the use of the NOACs as alternative agents in the treatment of HIT. Positive results have been reported for the use of NOACs in the treatment of HIT. Further robust studies are needed for definitive decision making by clinicians. PMID:27102287

  18. Parenteral anticoagulation in patients with cancer who have no therapeutic or prophylactic indication for anticoagulation

    NARCIS (Netherlands)

    E.A. Akl; S. Gunukula; M. Barba; V.E.D. Yosuico; F.F. van Doormaal; S. Kuipers; S. Middeldorp; H.O. Dickinson; A. Bryant; H. Schuenemann

    2011-01-01

    Background Anticoagulation may improve survival in patients with cancer through an antitumor effect in addition to the perceived antithrombotic effect. Objectives To evaluate the efficacy and safety of parenteral anticoagulants in patients with cancer with no therapeutic or prophylactic indication f

  19. Heat dissipation guides activation in signaling proteins.

    Science.gov (United States)

    Weber, Jeffrey K; Shukla, Diwakar; Pande, Vijay S

    2015-08-18

    Life is fundamentally a nonequilibrium phenomenon. At the expense of dissipated energy, living things perform irreversible processes that allow them to propagate and reproduce. Within cells, evolution has designed nanoscale machines to do meaningful work with energy harnessed from a continuous flux of heat and particles. As dictated by the Second Law of Thermodynamics and its fluctuation theorem corollaries, irreversibility in nonequilibrium processes can be quantified in terms of how much entropy such dynamics produce. In this work, we seek to address a fundamental question linking biology and nonequilibrium physics: can the evolved dissipative pathways that facilitate biomolecular function be identified by their extent of entropy production in general relaxation processes? We here synthesize massive molecular dynamics simulations, Markov state models (MSMs), and nonequilibrium statistical mechanical theory to probe dissipation in two key classes of signaling proteins: kinases and G-protein-coupled receptors (GPCRs). Applying machinery from large deviation theory, we use MSMs constructed from protein simulations to generate dynamics conforming to positive levels of entropy production. We note the emergence of an array of peaks in the dynamical response (transient analogs of phase transitions) that draw the proteins between distinct levels of dissipation, and we see that the binding of ATP and agonist molecules modifies the observed dissipative landscapes. Overall, we find that dissipation is tightly coupled to activation in these signaling systems: dominant entropy-producing trajectories become localized near important barriers along known biological activation pathways. We go on to classify an array of equilibrium and nonequilibrium molecular switches that harmonize to promote functional dynamics. PMID:26240354

  20. Study on Anti-Coagulant Activity of Sulfated Nsotoc Sphaeroides Kützing Polysaccharide%葛仙米多糖硫酸酯抗凝血活性研究

    Institute of Scientific and Technical Information of China (English)

    朱玉婷; 袁杰; 杨洁; 田瑞; 曾智; 莫开菊

    2014-01-01

    This paper investigated the anticoagulant activity of Nostoc Sphaeroides Kützing polysaccha-ride’ s sulfuric acid ester,whose substitution degrees were 0,0.51,1.01 respectively.The results showed:Nostoc Sphaeroides Kützing polysaccharide’ s sulfuric acid ester could obviously prolong APTT and TT, and depended on the concentration but did not play a significant role to PT.So the results mainly illustra-ted that it played the function of anticlotting through inhibiting endogenous blood coagulation process and conjunct blood coagulation way,but it showed weak effect on exogenous blood coagulation way.%以取代度为0、0.51、1.01的葛仙米多糖硫酸酯为原料,探讨了各样品的抗凝血活性.结果表明:葛仙米多糖硫酸酯能显著延长人活化部分凝血活酶时间(APTT)和凝血酶时间(TT),且具有一定的剂量效应关系,但对凝血酶原时间(PT)的作用不明显.说明其主要是通过抑制内源性凝血过程及共同凝血途径发挥抗凝血作用,对外源凝血途径影响较弱.

  1. Structural Analysis and Anticoagulant Activities of the Novel Sulfated Fucan Possessing a Regular Well-Defined Repeating Unit from Sea Cucumber

    OpenAIRE

    Wu, Mingyi; Xu, Li; Zhao, Longyan; Xiao, Chuang; Gao, Na; Luo, Lan; Yang, Lian; Li, Zi; Chen, Lingyun; Zhao, Jinhua

    2015-01-01

    Sulfated fucans, the complex polysaccharides, exhibit various biological activities. Herein, we purified two fucans from the sea cucumbers Holothuria edulis and Ludwigothurea grisea. Their structures were verified by means of HPGPC, FT-IR, GC–MS and NMR. As a result, a novel structural motif for this type of polymers is reported. The fucans have a unique structure composed of a central core of regular (1→2) and (1→3)-linked tetrasaccharide repeating units. Approximately 50% of the units from ...

  2. Honey Bee Venom (Apis mellifera) Contains Anticoagulation Factors and Increases the Blood-clotting Time

    OpenAIRE

    Hossein Zolfagharian; Mohammad Mohajeri; Mahdi Babaie

    2015-01-01

    Objectives: Bee venom (BV) is a complex mixture of proteins and contains proteins such as phospholipase and melittin, which have an effect on blood clotting and blood clots. The mechanism of action of honey bee venom (HBV, Apis mellifera) on human plasma proteins and its anti-thrombotic effect were studied. The purpose of this study was to investigate the anti-coagulation effect of BV and its effects on blood coagulation and purification. Methods: Crude venom obtained from Apis mellifera was ...

  3. Excessive anticoagulation with warfarin or phenprocoumon may have multiple causes

    DEFF Research Database (Denmark)

    Meegaard, Peter Martin; Holck, Line H V; Pottegård, Anton;

    2012-01-01

    Excessive anticoagulation with vitamin K antagonists is a serious condition with a substantial risk of an adverse outcome. We thus found it of interest to review a large case series to characterize the underlying causes of excessive anticoagulation....

  4. Interrupting Anticoagulation in Patients With Nonvalvular Atrial Fibrillation

    OpenAIRE

    Yates, Scott W

    2014-01-01

    No agents are approved to reverse the effects of newer anticoagulants used to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. This review focuses on ways to monitor, interrupt, and reverse such anticoagulation.

  5. Anticoagulant conversion in the elderly: pitfalls.

    Science.gov (United States)

    Al-Nasser, Bassam

    2016-05-01

    The prevalence of medical conditions representing a risk for thromboembolic complications and requiring antithrombotic therapy increases gradually with age. Two cases of fatal noncritical organ bleeding complication that occurred during the conversion period from initial fondaparinux to vitamin K antagonist are presented. An 81-year-old obese female patient (body mass index 43 kg/m(2)) with previous postoperative thrombosis underwent uneventful total knee replacement under spinal anesthesia. She presented with popliteal hematoma during conversion to oral anticoagulant. A 92-year-old female patient (body mass index 33 kg/m(2)) with left lower limb thrombosis was referred to our orthopedics department from her senior citizens' home for right lower limb hematoma and ischemia that occurred during conversion to oral anticoagulant. Thromboembolic and bleeding events in the elderly are real public health problems. Specific guidelines dedicated to this particular population are needed, which will improve the management of anticoagulation and decrease risk of complications. PMID:26547115

  6. Pharmacology of anticoagulants used in the treatment of venous thromboembolism

    OpenAIRE

    Nutescu, Edith A.; Burnett, Allison; Fanikos, John; Spinler, Sarah; Wittkowsky, Ann

    2016-01-01

    Anticoagulant drugs are the foundation of therapy for patients with VTE. While effective therapeutic agents, anticoagulants can also result in hemorrhage and other side effects. Thus, anticoagulant therapy selection should be guided by the risks, benefits and pharmacologic characteristics of each agent for each patient. Safe use of anticoagulants requires not only an in-depth knowledge of their pharmacologic properties but also a comprehensive approach to patient management and education. Thi...

  7. Hematometra secondary to anticoagulant rodenticide toxicity

    International Nuclear Information System (INIS)

    An adult, intact female Australian shepherd presented for frank vaginal bleeding of unknown duration. The only coagulation profile abnormality upon presentation was mild prolongation of the partial thromboplastin time (PTT). The uterus was removed at surgery and contained a large amount of coagulated blood. Clotting profiles were markedly abnormal48 hours postoperatively. Serum analysis was positive for brodifacoum, an anticoagulant rodenticide. Preoperative coagulation was most likely normalized by vitamin K-1 therapy administered prior to presentation. The only manifestation of anticoagulant rodenticide was hematometra. Rodenticide intoxication should be considered in the differential diagnosis list of hematometra or metrorrhagia

  8. Fatal pulmonary hemorrhage after taking anticoagulation medication

    Directory of Open Access Journals (Sweden)

    Samuel P. Hammar

    2015-01-01

    Full Text Available We describe a 64-year-old man with extensive diffuse acute lung hemorrhage, presumably as a result of anticoagulation therapy. We evaluated reports in the literature concerning acute exacerbation (acute lung injury of unknown cause in UIP and other forms of fibrotic interstitial pneumonias. We also evaluated autopsy tissue in this case in order to determine the cause of death in this 64-year-old man, who was initially thought to have an asbestos-related disease. Based on the autopsy findings, this man died as a result of anticoagulation therapy; specifically, the use of Xarelto® (rivaroxaban.

  9. Arabinogalactan proteins: focus on carbohydrate active enzymes

    Directory of Open Access Journals (Sweden)

    Eva eKnoch

    2014-06-01

    Full Text Available Arabinogalactan proteins (AGPs are a highly diverse class of cell surface proteoglycans that are commonly found in most plant species. AGPs play important roles in many cellular processes during plant development, such as reproduction, cell proliferation, pattern formation and growth, and in plant-microbe interaction. However, little is known about the molecular mechanisms of their function. Numerous studies using monoclonal antibodies that recognize different AGP glycan epitopes have shown the appearance of a slightly altered AGP glycan in a specific stage of development in plant cells. Therefore, it is anticipated that the biosynthesis and degradation of AGP glycan is tightly regulated during development. Until recently, however, little was known about the enzymes involved in the metabolism of AGP glycans. In this review, we summarize recent discoveries of carbohydrate active enzymes (CAZy; http://www.cazy.org/ involved in the biosynthesis and degradation of AGP glycans, and we discuss the biological role of these enzymes in plant development.

  10. Syndecans: synergistic activators of cell adhesion

    DEFF Research Database (Denmark)

    Woods, A; Couchman, J R

    1998-01-01

    Cell-surface proteoglycans participate in cell adhesion, growth-factor signalling, lipase activity and anticoagulation. Until recently, only the roles of the glycosaminoglycan chains were investigated. Now, with molecular characterization of several core proteins, the roles of each individual...... molecules modulating integrin-based adhesion....

  11. Reconstitution of Membrane Proteins into Model Membranes: Seeking Better Ways to Retain Protein Activities

    OpenAIRE

    Trevor Lithgow; Lisa Martin; Hsin-Hui Shen

    2013-01-01

    The function of any given biological membrane is determined largely by the specific set of integral membrane proteins embedded in it, and the peripheral membrane proteins attached to the membrane surface. The activity of these proteins, in turn, can be modulated by the phospholipid composition of the membrane. The reconstitution of membrane proteins into a model membrane allows investigation of individual features and activities of a given cell membrane component. However, the activity of mem...

  12. Activated protein C ameliorates Bacillus anthracis lethal toxin-induced lethal pathogenesis in rats

    Directory of Open Access Journals (Sweden)

    Kau Jyh-Hwa

    2012-11-01

    Full Text Available Abstract Background Lethal toxin (LT is a major virulence factor of Bacillus anthracis. Sprague Dawley rats manifest pronounced lung edema and shock after LT treatments, resulting in high mortality. The heart failure that is induced by LT has been suggested to be a principal mechanism of lung edema and mortality in rodents. Since LT-induced death occurs more rapidly in rats than in mice, suggesting that other mechanisms in addition to the heart dysfunction may be contributed to the fast progression of LT-induced pathogenesis in rats. Coagulopathy may contribute to circulatory failure and lung injury. However, the effect of LT on coagulation-induced lung dysfunction is unclear. Methods To investigate the involvement of coagulopathy in LT-mediated pathogenesis, the mortality, lung histology and coagulant levels of LT-treated rats were examined. The effects of activated protein C (aPC on LT-mediated pathogenesis were also evaluated. Results Fibrin depositions were detected in the lungs of LT-treated rats, indicating that coagulation was activated. Increased levels of plasma D-dimer and thrombomodulin, and the ameliorative effect of aPC further suggested that the activation of coagulation-fibrinolysis pathways plays a role in LT-mediated pathogenesis in rats. Reduced mortality was associated with decreased plasma levels of D-dimer and thrombomodulin following aPC treatments in rats with LT-mediated pathogenesis. Conclusions These findings suggest that the activation of coagulation in lung tissue contributes to mortality in LT-mediated pathogenesis in rats. In addition, anticoagulant aPC may help to develop a feasible therapeutic strategy.

  13. Monitoring Oral Anticoagulant Therapy: Measuring Coagulant Activity

    DEFF Research Database (Denmark)

    Attermann, Jorn

    clinical chemistry departments. In the second substudy we investigated the fundamental assumptions of the INR system. We found that the data from the comparison of three thromboplastin preparations (CRM 149S, Nycotest and Hepato Quick) were consistent with these assumptions and concluded that the INR...

  14. Pharmacology of anticoagulants used in the treatment of venous thromboembolism.

    Science.gov (United States)

    Nutescu, Edith A; Burnett, Allison; Fanikos, John; Spinler, Sarah; Wittkowsky, Ann

    2016-01-01

    Anticoagulant drugs are the foundation of therapy for patients with VTE. While effective therapeutic agents, anticoagulants can also result in hemorrhage and other side effects. Thus, anticoagulant therapy selection should be guided by the risks, benefits and pharmacologic characteristics of each agent for each patient. Safe use of anticoagulants requires not only an in-depth knowledge of their pharmacologic properties but also a comprehensive approach to patient management and education. This paper will summarize the key pharmacologic properties of the anticoagulant agents used in the treatment of patients with VTE. PMID:26780737

  15. Mitogen-activated protein kinase signaling in plants

    DEFF Research Database (Denmark)

    Rodriguez, Maria Cristina Suarez; Petersen, Morten; Mundy, John

    2010-01-01

    Eukaryotic mitogen-activated protein kinase (MAPK) cascades have evolved to transduce environmental and developmental signals into adaptive and programmed responses. MAPK cascades relay and amplify signals via three types of reversibly phosphorylated kinases leading to the phosphorylation of...... substrate proteins, whose altered activities mediate a wide array of responses, including changes in gene expression. Cascades may share kinase components, but their signaling specificity is maintained by spaciotemporal constraints and dynamic protein-protein interactions and by mechanisms that include...

  16. Human cytomegalovirus IE2 protein interacts with transcription activating factors

    Institute of Scientific and Technical Information of China (English)

    徐进平; 叶林柏

    2002-01-01

    The human cytomegalovirus (HCMV) IE86 Cdna was cloned into Pgex-2T and fusion protein GST-IE86 was expressed in E. Coli. SDS-PAGE and Western blot assay indicated that fusion protein GST-IE86 with molecular weight of 92 ku is soluble in the supernatant of cell lysate. Protein GST and fusion protein GST-IE86 were purified by affinity chromatography. The technology of co-separation and specific affinity chromatography was used to study the interactions of HCMV IE86 protein with some transcriptional regulatory proteins and transcriptional factors. The results indicated that IE86 interacts separately with transcriptional factor TFIIB and promoter DNA binding transcription trans-activating factors SP1, AP1 and AP2 to form a heterogenous protein complex. These transcriptional trans-activating factors, transcriptional factor and IE86 protein were adsorbed and retained in the affinity chromatography simultaneously. But IE86 protein could not interact with NF-Кb, suggesting that the function of IE86 protein that can interact with transcriptional factor and transcriptional trans-activating factors has no relevance to protein glycosylation. IE86 protein probably has two domains responsible for binding transcriptional trans-activating regulatory proteins and transcriptional factors respectively, thus activating the transcription of many genes. The interactions accelerated the assembly of the transcriptional initiation complexes.

  17. Anticoagulation, ferrotoxicity and the future of translational lung cancer research.

    Science.gov (United States)

    Zacharski, Leo R

    2016-06-01

    Numerous studies have shown that elements of coagulation reactions mediate tumor cell proliferation, motility (invasiveness), tissue remodeling and metastasis. Coagulation activation is virtually a universal feature of human malignancy that differs from the clotting response to injury in that it is self-perpetuating rather than self-attenuating. Coagulation activation participates in tumor matrix deposition and local inflammation, and predicts subsequent cancer risk and adverse cancer outcomes. Several clinical trials of anticoagulants have shown improved outcomes in small cell carcinoma of the lung (SCCL) that have been correlated with assembly on the tumor cells of an intact coagulation pathway. However, variable efficacy of anticoagulant therapy has raised doubts about the coagulation hypothesis. Recently, initiators of coagulation and fibrinolytic pathways have been identified that mediate tumor inception and progression. Notable among these is oxidative stress driven by iron-catalyzed reactive oxygen species that may be the basis for local coagulation activation, tumor matrix deposition, inflammation and aberrant properties characteristic of the malignant phenotype. Recognition of important biological characteristics of individual tumor types, disease stage, choice of standard therapy including chemotherapy and the iron status of the host may clarify mechanisms. All of these are subject to modification based on controlled clinical trial design. Further tests of the coagulation hypothesis may lead to novel, low cost and relatively non-toxic approaches to treatment of malignancy including lung cancer that contrast with certain current cancer treatment paradigms. PMID:27413710

  18. Anticoagulation, ferrotoxicity and the future of translational lung cancer research

    Science.gov (United States)

    2016-01-01

    Numerous studies have shown that elements of coagulation reactions mediate tumor cell proliferation, motility (invasiveness), tissue remodeling and metastasis. Coagulation activation is virtually a universal feature of human malignancy that differs from the clotting response to injury in that it is self-perpetuating rather than self-attenuating. Coagulation activation participates in tumor matrix deposition and local inflammation, and predicts subsequent cancer risk and adverse cancer outcomes. Several clinical trials of anticoagulants have shown improved outcomes in small cell carcinoma of the lung (SCCL) that have been correlated with assembly on the tumor cells of an intact coagulation pathway. However, variable efficacy of anticoagulant therapy has raised doubts about the coagulation hypothesis. Recently, initiators of coagulation and fibrinolytic pathways have been identified that mediate tumor inception and progression. Notable among these is oxidative stress driven by iron-catalyzed reactive oxygen species that may be the basis for local coagulation activation, tumor matrix deposition, inflammation and aberrant properties characteristic of the malignant phenotype. Recognition of important biological characteristics of individual tumor types, disease stage, choice of standard therapy including chemotherapy and the iron status of the host may clarify mechanisms. All of these are subject to modification based on controlled clinical trial design. Further tests of the coagulation hypothesis may lead to novel, low cost and relatively non-toxic approaches to treatment of malignancy including lung cancer that contrast with certain current cancer treatment paradigms.

  19. Bivalirudin as an adjunctive anticoagulant to heparin in the treatment of heparin resistance during cardiopulmonary bypass-assisted cardiac surgery.

    Science.gov (United States)

    McNair, E; Marcoux, J-A; Bally, C; Gamble, J; Thomson, D

    2016-04-01

    Heparin resistance (unresponsiveness to heparin) is characterized by the inability to reach acceptable activated clotting time values following a calculated dose of heparin. Up to 20% of the patients undergoing cardiothoracic surgery with cardiopulmonary bypass using unfractionated heparin (UFH) for anticoagulation experience heparin resistance. Although UFH has been the "gold standard" for anticoagulation, it is not without its limitations. It is contraindicated in patients with confirmed heparin-induced thrombocytopenia (HIT) and heparin or protamine allergy. The safety and efficacy of the use of the direct thrombin inhibitor bivalirudin for anticoagulation during cardiac surgery has been reported. However, there have been no reports on the treatment of heparin resistance with bivalirudin during CPB. In this review, we report the favorable outcome of our single-center experience with the alternative use of bivalirudin in the management of anticoagulation of heparin unresponsive patients undergoing coronary artery bypass graft surgery. PMID:25934498

  20. 4-hydroxy-2, 3-nonenal activates activator protein-1 and mitogen-activated protein kinases in rat pancreatic stellate cells

    Institute of Scientific and Technical Information of China (English)

    Kazuhiro Kikuta; Atsushi Masamune; Masahiro Satoh; Noriaki Suzuki; Tooru Shimosegawa

    2004-01-01

    AIM: Activated pancreatic stellate cells (PSCs) are implicated in the pathogenesis of pancreatic inflammation and fibrosis,where oxidative stress is thought to play a key role. 4-hydroxy2,3-nonenal (HNE) is generated endogenously during the process of lipid peroxidation, and has been accepted as a mediator of oxidative stress. The aim of this study was to clarify the effects of HNE on the activation of signal transduction pathways and cellular functions in PSCs.METHODS: PSCs were isolated from the pancreas of male Wistar rats after perfusion with collagenase P, and used in their culture-activated, myofibroblast-like phenotype unless otherwise stated. PSCs were treated with physiologically relevant and non-cytotoxic concentrations (up to 5 μmol/L)of HNE. Activation of transcription factors was examined by electrophoretic mobility shift assay and luciferase assay.Activation of mitogen-activated protein (MAP) kinases was assessed by Western blotting using anti-phosphospecific antibodies. Cell proliferation was assessed by measuring the incorporation of 5-bromo-2'-deoxyuridine. Production of type Ⅰ collagen and monocyte chemoattractant protein-1was determined by enzyme-linked immunosorbent assay.The effect of HNE on the transformation of freshly isolated PSCs in culture was also assessed.RESULTS: HNE activated activator protein-1, but not nuclear factor κB. In addition, HNE activated three classes of MAP kinases: extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 MAP kinase. HNE increased type Ⅰ collagen production through the activation of p38 MAP kinase and c-Jun N-terminal kinase. HNE did not alter the proliferation,or monocyte chemoattractant protein-1 production. HNE did not initiate the transformation of freshly isolated PSCs to myofibroblast-like phenotype.CONCLUSION: Specific activation of these signal transduction pathways and altered cell functions such as collagen production by HNE may play a role in the pathogenesis of pancreatic

  1. Antioxidant activity of black bean (Phaseolus vulgaris L. protein hydrolysates

    Directory of Open Access Journals (Sweden)

    Jarine Amaral do EVANGELHO

    2016-01-01

    Full Text Available Abstract The objective of this work was to study the effect of enzymatic hydrolysis of black bean protein concentrate using different enzymes. Bean proteins were extracted and hydrolyzed over a period of 120 min using the enzymes pepsin or alcalase. The protein hydrolysates’ molecular weight was assayed by electrophoresis and the antioxidant activity was evaluated by the capturing methods of free radicals ABTS●+ and DPPH. Electrophoretic results showed that the bands above 50 kDa disappeared, when the beans protein was subjected to hydrolysis with pepsin. The bean protein hydrolysate obtained by hydrolysis with alcalase enzyme, showed higher antioxidant activity for inhibition of the radical ABTS●+. However, the hydrolysates obtained by hydrolysis with pepsin had higher antioxidant activity for inhibition of the radical DPPH. The use of pepsin and alcalase enzymes, under the same reaction time, produced black bean protein hydrolysates with different molecular weight profiles and superior antioxidant activity than the native bean protein.

  2. Heat dissipation guides activation in signaling proteins

    OpenAIRE

    Weber, Jeffrey K.; Shukla, Diwakar; Pande, Vijay S.

    2015-01-01

    As with their macroscopic counterparts, the moving parts of nanoscale protein machines grow hot while in operation. A portion of the energy biomolecules harness to perform meaningful work is always dissipated as heat into the surroundings. Here, we feature a methodology by which dominant dissipative trajectories can be extracted from detailed models of protein dynamics. In two important classes of signaling proteins [kinases and G-protein–coupled receptors (GPCRs)], we find that the regions o...

  3. Serum paraoxonase activity and protein thiols in patients with hyperlipidemia

    Institute of Scientific and Technical Information of China (English)

    Mungli Prakash; Jeevan K Shetty; Sudeshna Tripathy; Pannuri Vikram; Manish Verma

    2009-01-01

    Objective: In the present study we evaluated the paraoxonase activity and protein thiols level in south Indian population with newly diagnosed hyperlipidemia. Methods: The study was conducted on 55 newly diagnosed hyperlipidemic pa-tients and 57 healthy controls. Serum paraoxonase activity and protein thiols were estimated by spectrophotometeric method and lipid profile by enzymatic kinetic assay method. Results: Serum paraoxonase activity, protein thiols and high density lipoprotein levels were low and total cholesterol, triglycerides and low density lipoprutein levels were high in patients with hyperlipidemia compared to healthy controls ( P < 0.01 ). Serum paranxonase activity correlated positively with protein thiols and high density lipoprotein (P<0.01). Conclusion: Decreased paraoxonase activity and protein thiols were found in patients with hyperlipi-demia. This may indicate the susceptibility of this population to accelerated atherogenesis and protein oxidation.

  4. Role of Antiplatelet Therapy and Anticoagulation in Nonischemic Cardiomyopathy.

    Science.gov (United States)

    Carazo, Matthew; Berger, Jeffrey S; Reyentovich, Alex; Katz, Stuart D

    2016-01-01

    Heart failure continues to be a leading cause of morbidity and mortality throughout the United States. The pathophysiology of heart failure involves the activation of complex neurohormonal pathways, many of which mediate not only hypertrophy and fibrosis within ventricular myocardium and interstitium, but also activation of platelets and alteration of vascular endothelium. Platelet activation and vascular endothelial dysfunction may contribute to the observed increased risk of thromboembolic events in patients with chronic heart failure. However, current data from clinical trials do not support the routine use of chronic antiplatelet or oral anticoagulation therapy for ambulatory heart failure patients without other indications (atrial fibrillation and/or coronary artery disease) as the risk of bleeding seems to outweigh the potential benefit related to reduction in thromboembolic events. In this review, we consider the potential clinical utility of targeting specific pathophysiological mechanisms of platelet and vascular endothelial activation to guide clinical decision making in heart failure patients. PMID:26501990

  5. Active Nuclear Import of Membrane Proteins Revisited

    NARCIS (Netherlands)

    Laba, Justyna K; Steen, Anton; Popken, Petra; Chernova, Alina; Poolman, Bert; Veenhoff, Liesbeth M

    2015-01-01

    It is poorly understood how membrane proteins destined for the inner nuclear membrane pass the crowded environment of the Nuclear Pore Complex (NPC). For the Saccharomyces cerevisiae proteins Src1/Heh1 and Heh2, a transport mechanism was proposed where the transmembrane domains diffuse through the m

  6. Modeling Protein Folding and Applying It to a Relevant Activity

    Science.gov (United States)

    Nelson, Allan; Goetze, Jim

    2004-01-01

    The different levels of protein structure that can be easily understood by creating a model that simulates protein folding, which can then be evaluated by applying it to a relevant activity, is presented. The materials required and the procedure for constructing a protein folding model are mentioned.

  7. A simple method to discriminate between beta(2)-glycoprotein I- and prothrombin-dependent lupus anticoagulants

    NARCIS (Netherlands)

    Simmelink, MJA; Derksen, RHWM; Arnout, J; De Groot, PG

    2003-01-01

    Lupus anticoagulants (LAC) are a heterogeneous group of autoantibodies that prolong phospholipid-dependent clotting assays. The autoantibodies that cause LAC activity are predominantly directed against beta(2)-glycoprotein I (beta(2)GPI) or prothrombin. In the present study, we describe a method to

  8. Low anticoagulant heparin oligosaccharides as inhibitors of BACE-1, the Alzheimer's β-secretase.

    Science.gov (United States)

    Zhang, Xiao; Zhao, Xiaoliang; Lang, Yinzhi; Li, Qinying; Liu, Xiaoxiao; Cai, Chao; Hao, Jiejie; Li, Guoyun; Yu, Guangli

    2016-10-20

    Heparin (HP) is a promising agent for anti-Alzheimer's disease (AD), but its anticoagulant activity limits its applications. So a low anticoagulant heparin (LAH) with anti-AD effect is needed. A novel LAH and heparan sulfate (HS) were purified from crude porcine intestinal heparin. Their structures were characterized by nuclear magnetic resonance and liquid chromatography-mass spectrometry. LAH had a relatively high degree of sulfation, but lower than that of HP. 3-O-Sulfated-containing glucosamine residues further confirmed the low anticoagulant activity of LAH. Sixteen oligosaccharides of LAH and HS were prepared and assigned. Evaluation of anti-BACE-1 activities suggested that their potencies were positively correlated with degree of sulfation and polymerization of oligosaccharides. Besides, LAH-derived hexa- to dodecasaccharides was promised to be administrated in vitro as BACE-1 inhibitors. This study presented ideal BACE-1 inhibitors, LAH-derived oligosaccharides, with virtually no anticoagulant activities, which were promised to be excellent leads for treatment of AD. PMID:27474542

  9. In vitro anticoagulation monitoring of low-molecular-weight heparin

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-qi; SHI Xu-bo; YANG Jin-gang; HU Da-yi

    2009-01-01

    Background Although low-molecular-weight heparin has replaced unfractionated heparin to become the primary anticoagulation drug for treatment of acute coronary syndrome, there is no convenient bedside monitoring method. We explored the best laboratory monitoring method of low-molecular-weight heparins (enoxapadn, dalteparin, and nadroparin) by use of the Sonoclot coagulation analyzer to monitor the activated clotting time.Methods Atotal of 20 healthy volunteers were selected and 15 ml of fasting venous blood samples were collected and incubated. Four coagulants, kaolin, diatomite, glass bead, and magnetic stick, were used to determine the activated clotting time of the low-molecular-weight heparins at different in vitro anti-Xa factor concentrations. A correlation analysis was made to obtain the regression equation. The activated clotting time of the different low-molecular-weight heparins with the same anti-Xa factor concentration was monitored when the coagulant glass beads were applied. Results The activated clotting time measured using the glass beads, diatomite, kaolin, and magnetic stick showed a linear correlation with the concentration of nadroparin (r= 0.964, 0.966, 0.970, and 0.947, respectively). The regression equation showed that the linear slopes of different coagulants were significantly different (glass beads 230.03 s/IU,diatomite 89.91 s/IU, kaolin 50.87 s/IU, magnetic stick could not be calculated). When the concentration of the anti-Xa factor was the same for different low-molecular-weight heparins, the measured activated clotting time was different after the application of the glass bead coagulant.Conclusions The glass bead coagulant is most feasible for monitoring the in vitro anticoagulation activity of nadroparin.The different effects of different low-molecular-weight heparins on the activated clotting time may be related to the different anti-Ila activities.

  10. Taipan snake venom time coupled with ecarin time enhances lupus anticoagulant detection in nonanticoagulated patients.

    Science.gov (United States)

    Moore, Gary W; Culhane, Aidan P; Maloney, James C; Archer, Robert A; Breen, Karen A; Hunt, Beverley J

    2016-06-01

    A study is presented which assesses the diagnostic impact of incorporating Taipan snake venom time (TSVT) with ecarin time confirmatory test into an existing dilute Russell's viper venom time (dRVVT) and activated partial thromboplastin time (APTT) repertoire when testing nonanticoagulated patients for lupus anticoagulants. A total of 387 plasma samples from nonanticoagulated patients being investigated for antiphospholipid antibodies were tested for lupus anticoagulant by dRVVT and dilute APTT with confirmatory and mixing tests, and TSVT with ecarin time, with commercially available reagents. All were analyzed on a Sysmex CS2000i automated analyzer. Lupus anticoagulant was not detected by dRVVT, dilute APTT or TSVT screening in 265 of 387 (68.5%) samples. A lupus anticoagulant was detected in 60 (15.5%) samples in dRVVT and/or dilute APTT analysis, but gave normal TSVT ratios. Thirty-nine (10.1%) were positive by TSVT and ecarin time and one or both of dRVVT and dilute APTT testing, whereas a further 23 (5.9%) were only positive in TSVT/ecarin time testing. Most of the lupus anticoagulants manifested in dRVVT and/or APTT analysis, as might be anticipated for this reagent pairing. The samples positive by TSVT/ecarin time only, as has been previously demonstrated, emphasize that the many variables that impact lupus anticoagulant testing mean that even a well established dRVVT and APTT pairing cannot deliver diagnostic certainty. Interference by direct factor Xa inhibitors in dRVVT testing could pave the way for wider adoption of TSVT screening as we gain more evidence of its diagnostic performance. PMID:26656903

  11. Antioxidant activity of whey protein hydrolysates in milk beverage system

    OpenAIRE

    Mann, Bimlesh; Kumari, Anuradha; Kumar, Rajesh; Sharma, Rajan; Prajapati, Kishore; Mahboob, Shaik; Athira, S.

    2014-01-01

    The aim of the present study was to evaluate the antioxidant activity of flavoured milk enriched with antioxidative whey protein hydrolysates (WPHs) by radical scavenging method. Whey protein concentrate (WPC) was hydrolyzed by using three commercial proteases; flavouzyme, alcalase and corolase PP and these WPHs were analyzed for degree of hydrolysis and antioxidant activity. The antioxidant activities of these WPHs were evaluated using ABTS method. Trolox equivalent antioxidant activity of a...

  12. Deficiencies of Natural Anticoagulants, Protein C, Protein S, and Antithrombin

    Science.gov (United States)

    ... citing article information Citing articles via Google Scholar Google Scholar Articles by Lipe, B. Articles by Ornstein, D. L. Search for related content PubMed PubMed citation Articles by Lipe, B. Articles by Ornstein, D. ... Reddit StumbleUpon Twitter What's this? Navigate This ...

  13. Anticoagulation in adults with congenital heart disease

    DEFF Research Database (Denmark)

    Jensen, A S; Idorn, L; Nørager, B;

    2015-01-01

    Adults with congenital heart disease are a growing population. One of the major challenges in the care of these patients is to prevent thromboembolic episodes. Despite relative young age and no typical cardiovascular risk factors, this cohort has a high prevalence of thrombotic events. It is....... Furthermore, there is a lack of scientific evidence regarding how to prevent thromboembolic events with anticoagulation in adults with congenital heart disease. The aim of this paper is to review the current literature pertaining to anticoagulation in adults with congenital heart disease and hence enable...... difficult to use treatment algorithms from the general adult population with acquired heart disease in this heterogeneous population due to special conditions such as myocardial scarring after previous surgery, atypical atrial flutter, prothrombotic conditions and the presence of interatrial shunts...

  14. [Therapeutic equivalence of the new oral anticoagulants].

    Science.gov (United States)

    Moreno Villar, A; Nacle López, I; Barbero Hernández, M J; Lizan Tudela, L

    2015-10-01

    In an attempt to minimize the economic impact due to the incorporation of innovative drugs, health authorities have promoted and supported the evaluation and market positioning of drugs, as equivalent therapeutic alternatives. This issue has recently gained importance, possibly due to the current economic crisis. The equivalent therapeutic alternatives are justified by the need to compete on price, and by the authorities recommendation to establish therapeutic equivalence, price and financing of medicinal products at the same time. The establishment of the new oral anticoagulants and the equivalent therapeutic alternatives is a problematic issue if it is based on the absence of direct comparisons between different drugs and the questionable methodology used in the current indirect comparisons. Currently, it is difficult to determine when a new oral anticoagulant is more recommendable than others, but efforts are being made in order to propose alternatives for the decision based on patient characteristics. PMID:26146035

  15. DIETARY PROTEIN AND LACTOSE INCREASE TRANSLATION INITIATION FACTOR ACTIVATION AND TISSUE PROTEIN SYNTHESIS IN NEONATAL PIGS

    Science.gov (United States)

    Protein synthesis and eukaryotic initiation factor (eIF) activation are increased in muscle and liver of pigs parenterally infused with amino acids and insulin. To examine the effects of enteral protein and carbohydrate on protein synthesis, pigs (n = 42, 1.7 kg body wt) were fed isocaloric milk die...

  16. [New orally anticoagulants and brain stroke].

    Science.gov (United States)

    Kaczorowska, Beata; Pawełczyk, Małgorzata; Przybyła, Monika

    2016-05-26

    Brain stroke is a grave society problem. About 20% ischemic strokes are cardiac related problems. Atrial fibrillation (AF) is the most common cause of ischemic strokes. Decision to deploy anticoagulant treatment with AF patient depends on bleeding and thrombo-embolic risk which summerise scale CHA2DS2VASc and HAS-BLED. Past recent years in AF treatment anticoagulants from the group of vitamin K antagonist were used. At present in brain stroke prevention and systemic emboilment, new oral anticoagulants (NOA) which weren't worst than vitamin K antagonists, and they are recomendet in most cases of AF unrelated with heart valve defets. Useing NOA causes lower risk of bleeding, including intracranial heamorrhage. It is believed that this is related to the selective inhibition of specific coagulation factors, and respect other hemostatic mechanisms. Results from clinical studies NOA are encouraging, but still lacks clear answers regarding, among other things: long-term safety of treatment and economically viable in everyday clinical practice. In addition, to date there is no specific antidote for this group of drugs. PMID:27234866

  17. Novel oral anticoagulants in plastic surgery.

    Science.gov (United States)

    Munson, C F; Reid, A J

    2016-05-01

    Novel oral anticoagulants (NOACs) have emerged as a good alternative to warfarin in the prevention of stroke for patients with atrial fibrillation. NOAC use is increasing rapidly; therefore, greater understanding of their use in the perioperative period is important for optimal care. Studies and reviews that reported on the use of NOACs were identified, with particular focus on the perioperative period. PubMed was searched for relevant articles published between January 2000 and August 2015. The inevitable rise in the use of NOACs such as rivaroxaban (Xarelto™), apixaban (Eliquis™), edoxaban (Lixiana™) and dabigatran (Pradaxa™) may present a simplified approach to perioperative anticoagulant management due to fewer drug interactions, rapidity of onset of action and relatively short half-lives. Coagulation status, however, cannot reliably be monitored and no antidotes are currently available. When planning for discontinuation of NOACs, special consideration of renal function is required. Advice regarding the management of bleeding complications is provided for consideration in emergency surgery. In extreme circumstances, haemodialysis may be considered for bleeding with the use of dabigatran. NOACs will increasingly affect operative planning in plastic surgery. In order to reduce the incidence of complications associated with anticoagulation, the management of NOACs in the perioperative period requires knowledge of the time of last dose, renal function and the bleeding risk of the planned procedure. Consideration of these factors will allow appropriate interpretation of the current guidelines. PMID:27013144

  18. Lupus anticoagulants and antiphospholipid antibodies

    Science.gov (United States)

    ... tests may include: Activated Partial thromboplastin time (aPTT) Russell viper venom time Thromboplastin inhibition test Tests for ... Textbook of Rheumatology . 9th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap 82. Holbrook A, Schulman S, Witt DM, ...

  19. Purification, renaturation, and reconstituted protein kinase activity of the Sendai virus large (L) protein: L protein phosphorylates the NP and P proteins in vitro.

    OpenAIRE

    Einberger, H; Mertz, R; Hofschneider, P H; Neubert, W J

    1990-01-01

    Sodium dodecyl sulfate-solubilized Sendai virus large (L) protein was highly purified by a one-step procedure, using hydroxylapatite column chromatography. Monoclonal antibodies addressed to the carboxyl-terminal amino acid sequence of the L protein were used for monitoring L protein during purification. By removing sodium dodecyl sulfate from purified L protein, a protein kinase activity was successfully renatured. P and NP proteins served as its substrates. After immunoprecipitation with an...

  20. Non-vitamin K antagonist oral anticoagulation agents in anticoagulant naive atrial fibrillation patients

    DEFF Research Database (Denmark)

    Olesen, Jonas Bjerring; Sørensen, Rikke; Hansen, Morten Lock;

    2015-01-01

    AIMS: Non-vitamin K antagonist oral anticoagulation (NOAC) agents have been approved for stroke prophylaxis in atrial fibrillation (AF). We investigated 'real-world' information on how these drugs are being adopted. METHODS AND RESULTS: Using Danish nationwide administrative registers, we...... the drug came on market. By October, 2013, 40% were being started on warfarin and dabigatran, respectively, and another 20% were started on either rivaroxaban or apixaban. Rivaroxaban and apixaban users generally had a higher predicted risk of stroke and bleeding compared with warfarin and dabigatran users....... Older age, female gender, and prior stroke were some of the factors associated with NOAC use vs. warfarin, whereas chronic kidney disease, myocardial infarction, and heart failure showed the opposite association. CONCLUSION: Among oral anticoagulation-naïve AF patients initiated on oral anticoagulation...

  1. Pharmacist-managed oral anticoagulation therapy in the community setting.

    Science.gov (United States)

    Bouwmeester, Carla; Chim, Christine

    2013-05-01

    Pharmacists are at the forefront when caring for patients requiring anticoagulation resulting from chronic conditions, complex medications therapy, or at risk for drug interactions. As a consequence, there is a greater need for pharmacist-managed anticoagulation clinics in the community setting. This article will review special considerations for oral anticoagulant therapy in the elderly, collaborative therapy management, establishment of policies and procedures, documentation of patient visits, patient counseling, and barriers to successful anticoagulation management. It will also discuss evidence-based guidelines for the use of oral anticoagulants and compare the agents currently approved by the Food and Drug Administration. Finally, barriers to anticoagulation management will be examined, including issues with adherence and communication with patients and health care providers. PMID:23649677

  2. Putative novel mediators of acute kidney injury in critically ill patients: handling by continuous venovenous hemofiltration and effect of anticoagulation modalities

    OpenAIRE

    Schilder, Louise; Nurmohamed, S Azam; ter Wee, Pieter M.; Paauw, Nanne J.; Girbes, Armand RJ; Beishuizen, Albertus; Beelen, Robert HJ; Groeneveld, AB Johan

    2015-01-01

    Background Novel putative mediators of acute kidney injury (AKI) include immune-cell derived tumour necrosis factor-like weak inducer of apoptosis (TWEAK), angiopoietin-2 (Ang-2) and protein pentraxin-3 (PTX3). The effect of continuous venovenous hemofiltration (CVVH) and different anticoagulation regimens on plasma levels were studied. Methods At 0, 10, 60, 180 and 720 min of CVVH, samples were collected from pre- and postfilter blood and ultrafiltrate. No anticoagulation (n = 13), unfractio...

  3. An audit of anticoagulant management to assess anticoagulant control using decision support software

    Science.gov (United States)

    Harper, Paul; Harper, Joe; Hill, Claire

    2014-01-01

    Objective To evaluate the effectiveness of a computerised self-adjusting anticoagulant algorithm to predict appropriate warfarin dosing and to assess its use in clinical practice. Design A 3-year audit of anticoagulant control in patients managed by doctors and pharmacists using computer decision support and an evaluation of the impact of dose adjustments made by the users. Participants 3660 patients on oral anticoagulants; one-third of patients managed by doctors and two-thirds by pharmacists. Setting Anticoagulant supervision in primary care and pharmacies at 60 sites in New Zealand. Main outcome measures The time in the therapeutic range (TTR), the outcome of adherence to the computer dosing algorithm, the percentage of time the clinicians over-ride the algorithm and the impact of their intervention on anticoagulant control. Results A TTR of 72.9% was achieved for all patients. The TTR was significantly better in patients managed by pharmacists than doctors (75.1% versus 67.4%, ppharmacists. Conclusions The clinicians predominantly change the dose when the INR is below the therapeutic range. The changes are not necessary to correct for inaccuracies in the algorithm. The most likely explanation is the clinician's belief that their own dose adjustment would achieve better control; however, in practice, their changes tend to underdose patients. The doctors achieved poorer control than the pharmacists; this is in part due to the action of the doctors over-riding the algorithm. Our results imply that clinicians could achieve better anticoagulant control if they more closely followed the computer algorithm. PMID:25183709

  4. Use of anticoagulants in elderly patients: practical recommendations

    Directory of Open Access Journals (Sweden)

    Helia Robert-Ebadi

    2009-04-01

    Full Text Available Helia Robert-Ebadi, Grégoire Le Gal, Marc RighiniDivision of Angiology and Hemostasis (HRE, MR, Department of Internal Medicine, Geneva University Hospital and Faculty of Medicine, Geneva, Switzerland, and Department of Internal Medicine and Chest Diseases, EA 3878 (GETBO, Brest University Hospital, Brest, France (GLGAbstract: Elderly people represent a patient population at high thromboembolic risk, but also at high hemorrhagic risk. There is a general tendency among physicians to underuse anticoagulants in the elderly, probably both because of underestimation of thromboembolic risk and overestimation of bleeding risk. The main indications for anticoagulation are venous thromboembolism (VTE prophylaxis in medical and surgical settings, VTE treatment, atrial fibrillation (AF and valvular heart disease. Available anticoagulants for VTE prophylaxis and initial treatment of VTE are low molecular weight heparins (LMWH, unfractionated heparin (UFH or synthetic anti-factor Xa pentasaccharide fondaparinux. For long-term anticoagulation vitamin K antagonists (VKA are the first choice and only available oral anticoagulants nowadays. Assessing the benefit-risk ratio of anticoagulation is one of the most challenging issues in the individual elderly patient, patients at highest hemorrhagic risk often being those who would have the greatest benefit from anticoagulants. Some specific considerations are of utmost importance when using anticoagulants in the elderly to maximize safety of these treatments, including decreased renal function, co-morbidities and risk of falls, altered pharmacodynamics of anticoagulants especially VKAs, association with antiplatelet agents, patient education. Newer anticoagulants that are currently under study could simplify the management and increase the safety of anticoagulation in the future.Keywords: anticoagulation, elderly patients, venous thromboembolism, hemorrhagic risk, atrial fibrillation, thrombin inhibitors, factor Xa

  5. New anticoagulants for the prevention of venous thromboembolism

    OpenAIRE

    Becattini, Cecilia

    2010-01-01

    Cecilia Becattini, Alessandra Lignani, Giancarlo AgnelliInternal and Cardiovascular Medicine and Stroke Unit, University of Perugia, ItalyAbstract: Anticoagulant drugs have an essential role in the prevention and treatment of thromboembolic diseases. Currently available anticoagulants substantially reduce the incidence of thromboembolic events in a number of clinical conditions. However, these agents have limitations that strengthen the case for the development of new anticoagulants. An ideal...

  6. Anticoagulation for the Acute Management of Ischemic Stroke

    OpenAIRE

    Robinson, Austin A.; Ikuta, Kevin; Soverow, Jonathan

    2014-01-01

    Few prospective studies support the use of anticoagulation during the acute phase of ischemic stroke, though observational data suggest a role in certain populations. Depending on the mechanism of stroke, systemic anticoagulation may prevent recurrent cerebral infarction, but concomitantly carries a risk of hemorrhagic transformation. In this article, we describe a case where anticoagulation shows promise for ischemic stroke and review the evidence that has discredited its use in some circums...

  7. Efficacy and Safety of Novel Anticoagulants Compared with Established Agents

    OpenAIRE

    Rybak, Iwona; Ehle, Michael; Buckley, Leo; Fanikos, John

    2011-01-01

    Dabigatran, rivaroxaban, and apixaban are novel oral anticoagulants that offer major advantages over existing agents. The onset of the anticoagulant effect of these agents is rapid. Each agent has a predictable anticoagulant response that eliminates the need for monitoring. Clinical trials have been completed with all three agents in the prevention and treatment of the three leading causes of cardiovascular death: myocardial infarction, stroke, and venous thromboembolism (VTE). Novel agents h...

  8. Purification and characterization of an anticoagulant oligopeptide from Whitmania pigra Whitman

    Directory of Open Access Journals (Sweden)

    Xiaobei Zheng

    2015-01-01

    Full Text Available Background: Dried Whitmania pigra is used for the treatment of cardiovascular and cerebrovascular diseases in traditional Chinese medicine and hot water and alcohol extracts also have anticogulant activity. However, a lower molecular weight and more stable anticogulant is needed. Objective: The objective of the following study is to purify and characterize of an anticoagulant oligopeptide from Hirudo (Whitmania pigra Whitman. Materials and Methods: Gel filtration on Sephadex G 50, ion exchange on diethylaminoethyl cellulose, and semi prepared high performance liquid chromatography were used to purify Hirudo. Automated coagulation analyzer was used for evaluating anticoagulant activity. Molecular weight was measured by Matrix assisted laser desorption ionization time of flight mass spectrometry. Amino acid sequence of the oligopeptide was measured by amino acid sequence analyzer. Results: A new anticoagulant, named whitide, isolated from Hirudo was purified, with a molecular weight 1997.1 Da. Amino acid sequence of the oligopeptide was identified as Gly-Pro-ALa-Gly-Hyp-Val-Gly-Ala-Hyp-Gly-Gly-Hyp-Gly-Val-Arg-Gly-Leu-Hyp-Gly-Asp-Arg-Gly. The results revealed that its amino acid sequence had strong homology to various types of collagen. Conclusion: Whitide might be an orally anticoagulant for its hot and trypsin stable.

  9. Comprehensive characterization of anticoagulant rodenticides in sludge by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Gómez-Canela, Cristian; Lacorte, Silvia

    2016-08-01

    The occurrence of 10 commonly used anticoagulant rodenticides in centrifuged sludge of 27 wastewater treatment plants was evaluated using solid-liquid extraction (SLE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Activated carbon, alumina, and Florisil cartridges with methanol/dichloromethane as eluting solvents were tested in combination with primary-secondary amine (PSA) to optimize an efficient sample cleanup. PSA in combination with Florisil was the best methodology to extract anticoagulant rodenticides in sludge providing recoveries between 42 ± 0.5 and 100 ± 2 %. Warfarin, bromadiolone, ferulenol, and coumachlor were the most ubiquitous compounds in sludge at concentrations up to 84.2 ng g(-1) for the latter. Coumatetralyl, dicoumarol, and brodifacoum were detected sporadically at levels between 6.1 and 17.4 ng g(-1). On the contrary, acenocoumarol, difenacoum, and flocoumafen were not detected in any sample. Finally, we estimated the amount of anticoagulant rodenticides discharged via sludge in order to determine the potential impact to agricultural soil according to different sludge usage practices in the region investigated. This study demonstrates that anticoagulant rodenticides are accumulated in sludge during activated sludge treatment and that the application of sludge as fertilizers may pose a future environmental risk, if not controlled. PMID:27146526

  10. Protein determination in seeds by proton activation

    Science.gov (United States)

    Morales, J. R.; Dinator, M. I.; Cerda, P.

    1989-04-01

    A proton beam of 6.6 MeV has been used to produce 11C and 13N in Araucaria Araucana seeds. Their positron decay allows determination of the N/C ratio. In seeds the nitrogen content is associated to proteins while carbon is spread in the organic material. Samples were irradiated for about 10 min with a beam intensity of 5 nA on areas of 1 mm 2. Slices of the seed were radially explored, showing a larger concentration of protein in the center.

  11. Protein determination in seeds by proton activation

    Energy Technology Data Exchange (ETDEWEB)

    Morales, J.R.; Dinator, M.I. (Chile Univ., Santiago (Chile). Lab. de Fisica); Cerda, P. (Bio-Bio Univ., Chillan (Chile))

    1989-04-01

    A proton beam of 6.6 MeV has been used to produce /sup 11/C and /sup 13/N in Araucaria Araucana seeds. Their positron decay allows determination of the N/C ratio. In seeds the nitrogen content is associated to proteins while carbon is spread in the organic material. Samples were irradiated for about 10 min with a beam intensity of 5 nA on areas of 1 mm/sup 2/. Slices of the seed were radially explored, showing a larger concentration of protein in the center. (orig.).

  12. The Kaiser Permanente Colorado Clinical Pharmacy Anticoagulation Service as a model of modern anticoagulant care.

    Science.gov (United States)

    Witt, Daniel M

    2008-01-01

    The Clinical Pharmacy Anticoagulation Service (CPAS) at Kaiser Permanente Colorado grew from a single pharmacist assisting a single physician to a comprehensive service staffed by over 20 employees. CPAS provides care for over 7200 patients with each CPAS pharmacist managing all aspects of anticoagulation therapy for 150 to 500 patients. Unique aspects of CPAS include its centralized organization structure, the use of telepharmacy, collaboration drug therapy management agreement with referring physicians and a robust research agenda. Results of various CPAS research projects have been published in the peer-reviewed medical literature. PMID:18804262

  13. Monitoring G protein activation in cells with BRET

    Science.gov (United States)

    Masuho, Ikuo; Martemyanov, Kirill A.; Lambert, Nevin A.

    2016-01-01

    Summary Live-cell assays based on fluorescence and luminescence are now indispensable tools for the study of G protein signaling. Assays based on fluorescence and bioluminescence resonance energy transfer (FRET and BRET) have been particularly valuable for monitoring changes in second messengers, protein-protein interactions, and protein conformation. Here we describe a BRET assay that monitors the release of free Gβγ dimers after activation of heterotrimers containing Gα subunits from all four G protein subfamilies. This assay provides useful kinetic and pharmacological information with reasonably high throughput using standard laboratory equipment. PMID:26260597

  14. New constitutive latex osmotin-like proteins lacking antifungal activity.

    Science.gov (United States)

    Freitas, Cleverson D T; Silva, Maria Z R; Bruno-Moreno, Frederico; Monteiro-Moreira, Ana C O; Moreira, Renato A; Ramos, Márcio V

    2015-11-01

    Proteins that share similar primary sequences to the protein originally described in salt-stressed tobacco cells have been named osmotins. So far, only two osmotin-like proteins were purified and characterized of latex fluids. Osmotin from Carica papaya latex is an inducible protein lacking antifungal activity, whereas the Calotropis procera latex osmotin is a constitutive antifungal protein. To get additional insights into this subject, we investigated osmotins in latex fluids of five species. Two potential osmotin-like proteins in Cryptostegia grandiflora and Plumeria rubra latex were detected by immunological cross-reactivity with polyclonal antibodies produced against the C. procera latex osmotin (CpOsm) by ELISA, Dot Blot and Western Blot assays. Osmotin-like proteins were not detected in the latex of Thevetia peruviana, Himatanthus drasticus and healthy Carica papaya fruits. Later, the two new osmotin-like proteins were purified through immunoaffinity chromatography with anti-CpOsm immobilized antibodies. Worth noting the chromatographic efficiency allowed for the purification of the osmotin-like protein belonging to H. drasticus latex, which was not detectable by immunoassays. The identification of the purified proteins was confirmed after MS/MS analyses of their tryptic digests. It is concluded that the constitutive osmotin-like proteins reported here share structural similarities to CpOsm. However, unlike CpOsm, they did not exhibit antifungal activity against Fusarium solani and Colletotrichum gloeosporioides. These results suggest that osmotins of different latex sources may be involved in distinct physiological or defensive events. PMID:26231325

  15. Regional Anticoagulation with Citrate is Superior to Systemic Anticoagulation with Heparin in Critically Ill Patients Undergoing Continuous Venovenous Hemodiafiltration

    OpenAIRE

    Park, Joon-Sung; Kim, Gheun-Ho; Kang, Chong Myung; Lee, Chang Hwa

    2011-01-01

    Background/Aims Short hemofilter survival and anticoagulation-related life-threatening complications are major problems in systemic anticoagulation with heparin (SAH) for continuous renal replacement therapy (CRRT). The present study examined if regional anticoagulation with citrate (RAC) using commercially available solutions can overcome the associated problems of SAH to produce economical benefits. Methods Forty-six patients were assigned to receive SAH or RAC. We assessed the coagulation ...

  16. Anti-inflammatory, anticoagulant and antioxidant effects of aqueous extracts from Moroccan thyme varieties

    Institute of Scientific and Technical Information of China (English)

    Tarik; Khouya; Mhamed; Ramchoun; Abdelbassat; Hmidani; Souliman; Amrani; Hicham; Harnafi; Mohamed; Benlyas; Younes; Filali; Zegzouti; Chakib; Alem

    2015-01-01

    Objective: To evaluate the anti-inflammatory, anticoagulant and antioxidant effects of aqueous extracts of thyme varieties from Moroccan.Methods: The aqueous extracts of tree medicinal plants [Thymus atlanticus(T. atlanticus), Thymus satureioides and Thymus zygis(T. zygis)] were screened for their antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl radical-scavenging, ferric reducing antioxidant power assay, radical scavenging activity method, the inhibition of 2,2’-azobis(2-amidinopropane) dihydrochloride that induces oxidative erythrocyte hemolysis and thiobarbituric acid reactive substances assay. The anti-inflammatory activity of aqueous extracts was evaluated in vivo using croton oil-induced ear edema and carrageenan-induced paw edema in mice and rats, respectively. This extracts were evaluated in vitro for their anticoagulant activity at the different concentrations by partial thromboplastin time and prothrombin time activated. Results: All thyme varieties were found to possess considerable antioxidant activity and potent anti-inflammatory activity in the croton oil-induced edema. Administration of aqueous extracts of two varieties(50 mg/kg)(T. zygis and T. atlanticus) reduced significantly the carrageenaninduced paw edema similar to non-steroidal anti-inflammatory drug(indomethacin, 10 mg/kg). In partial thromboplastin time and prothrombin time tests, T. atlanticus and T. zygis extracts showed the strongest anticoagulant activity. In contrast, Thymus satureioides did not show the anticoagulant activity in these tests. Conclusions: All aqueous extracts possess considerable antioxidant activity and are rich in total polyphenol and flavonoid but they act differently in the process of inflammatory and coagulation studied. This study shows great variability of biological activities in thyme varieties.

  17. Hydrodynamic collective effects of active proteins in biological membranes

    CERN Document Server

    Koyano, Yuki; Mikhailov, Alexander S

    2016-01-01

    Lipid bilayers forming biological membranes are known to behave as viscous 2D fluids on submicrometer scales; usually they contain a large number of active protein inclusions. Recently, it has been shown [Proc. Nat. Acad. Sci. USA 112, E3639 (2015)] that such active proteins should in- duce non-thermal fluctuating lipid flows leading to diffusion enhancement and chemotaxis-like drift for passive inclusions in biomembranes. Here, a detailed analytical and numerical investigation of such effects is performed. The attention is focused on the situations when proteins are concentrated within lipid rafts. We demonstrate that passive particles tend to become attracted by active rafts and are accumulated inside them.

  18. Antioxidant activities of buttermilk proteins, whey proteins, and their enzymatic hydrolysates.

    Science.gov (United States)

    Conway, Valérie; Gauthier, Sylvie F; Pouliot, Yves

    2013-01-16

    The oxygen radical absorbance capacities (ORAC) and metal chelating capacities (MCC) of protein concentrates prepared from buttermilk and cheese whey by ultrafiltration were compared with those of skim milk protein. Samples were also heat-denatured and hydrolyzed by pepsin for 2 h followed by trypsin for 3 h. The highest MCC was obtained for hydrolyzed skim milk protein. ORAC values ranged from 554.4 to 1319.6 μmol Trolox equivalents/g protein, with the highest value obtained for hydrolyzed buttermilk protein. Liquid-phase isoelectric focusing (IEF) of this hydrolysate yielded peptide fractions with lower ORAC values. LC-MS analysis of the hydrolyzed skim milk and buttermilk proteins and IEF fractions of the latter showed that peptides derived from milk fat globule membrane proteins, primarily butyrophilin, could be responsible for the superior antioxidant activity of buttermilk. These results suggest overall that hydrolyzed buttermilk protein could be used as a source of natural antioxidants. PMID:23244578

  19. Anthocyanin antioxidant activity and partition behavior in whey protein emulsion.

    Science.gov (United States)

    Viljanen, Kaarina; Kylli, Petri; Hubbermann, Eva-Maria; Schwarz, Karin; Heinonen, Marina

    2005-03-23

    The antioxidant activities of anthocyanins and anthocyanin fractions isolated from blackcurrants, raspberries, and lingonberries were investigated in whey protein-stabilized emulsion. The extent of protein oxidation was measured by determining the loss of tryptophan fluorescence and formation of protein carbonyl compounds and that of lipid oxidation by conjugated diene hydroperoxides and hexanal analyses. The antioxidant activity of berry anthocyanins increased with an increase in concentration. Blackcurrant anthocyanins were the most potent antioxidants toward both protein and lipid oxidation at all concentrations due to the beneficial combination of delphinidin and cyanidin glycosides. Most berry anthocyanins (69.4-72.8%) partitioned into the aqueous phase of the emulsion, thus being located favorably for antioxidant action toward protein oxidation. The presence of the lipid decreased the share of anthocyanin in the aqueous phase. Thus, the structure of food affects the antioxidant activity by influencing the partitioning of the antioxidant. PMID:15769130

  20. Protein stability and enzyme activity at extreme biological temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Feller, Georges, E-mail: gfeller@ulg.ac.b [Laboratory of Biochemistry, Centre for Protein Engineering, Institute of Chemistry B6a, University of Liege, B-4000 Liege (Belgium)

    2010-08-18

    Psychrophilic microorganisms thrive in permanently cold environments, even at subzero temperatures. To maintain metabolic rates compatible with sustained life, they have improved the dynamics of their protein structures, thereby enabling appropriate molecular motions required for biological activity at low temperatures. As a consequence of this structural flexibility, psychrophilic proteins are unstable and heat-labile. In the upper range of biological temperatures, thermophiles and hyperthermophiles grow at temperatures > 100 {sup 0}C and synthesize ultra-stable proteins. However, thermophilic enzymes are nearly inactive at room temperature as a result of their compactness and rigidity. At the molecular level, both types of extremophilic proteins have adapted the same structural factors, but in opposite directions, to address either activity at low temperatures or stability in hot environments. A model based on folding funnels is proposed accounting for the stability-activity relationships in extremophilic proteins. (topical review)

  1. Antioxidant activity of black bean (Phaseolus vulgaris L.) protein hydrolysates

    OpenAIRE

    Jarine Amaral do EVANGELHO; Jose de J. BERRIOS; Vânia Zanella PINTO; Mariana Dias ANTUNES; Nathan Levien VANIER; Elessandra da Rosa ZAVAREZE

    2016-01-01

    Abstract The objective of this work was to study the effect of enzymatic hydrolysis of black bean protein concentrate using different enzymes. Bean proteins were extracted and hydrolyzed over a period of 120 min using the enzymes pepsin or alcalase. The protein hydrolysates’ molecular weight was assayed by electrophoresis and the antioxidant activity was evaluated by the capturing methods of free radicals ABTS●+ and DPPH. Electrophoretic results showed that the bands above 50 kDa disappeared,...

  2. Controlled Activation of Protein Rotational Dynamics Using Smart Hydrogel Tethering

    Energy Technology Data Exchange (ETDEWEB)

    Beech, Brenda M.; Xiong, Yijia; Boschek, Curt B.; Baird, Cheryl L.; Bigelow, Diana J.; Mcateer, Kathleen; Squier, Thomas C.

    2014-09-05

    Stimulus-responsive hydrogel materials that stabilize and control protein dynamics have the potential to enable a range of applications to take advantage of the inherent specificity and catalytic efficiencies of proteins. Here we describe the modular construction of a hydrogel using an engineered calmodulin (CaM) within a polyethylene glycol (PEG) matrix that involves the reversible tethering of proteins through an engineered CaM-binding sequence. For these measurements, maltose binding protein (MBP) was isotopically labeled with [13C] and [15N], permitting dynamic structural measurements using TROSY-HSQC NMR spectroscopy. Upon initial formation of hydrogels protein dynamics are suppressed, with concomitant increases in protein stability. Relaxation of the hydrogel matrix following transient heating results in the activation of protein dynamics and restoration of substrate-induced large-amplitude domain motions necessary for substrate binding.

  3. The Role of Anticoagulation Clinics in the Era of New Oral Anticoagulants

    Directory of Open Access Journals (Sweden)

    Sophie Testa

    2012-01-01

    Full Text Available Anticoagulation Clinics (ACs are services specialized in management of patients on anticoagulant treatment. At present, ACs manage patients chiefly on antivitamin K antagonists (AVKs, but patient population has already changed in the last few years, because of an increase of treatments with other anticoagulant drugs, which require different management systems. The strong increase in the number of patients at AC, mainly on long-term treatment, has determined the development of web management, through telemedicine systems, improving the quality of life and maintaining the same clinical quality levels. New oral anticoagulants (NOAs have shown to be as effective as AVK antagonists in stroke prevention in atrial fibrillation and for treatment of venous thromboembolism in addition to VTE prophylaxis in orthopaedic surgery, when administered at a fixed dose, but patient adherence and compliance are crucial for good quality treatment. At present, lacking data from the real world, an oversimplification of treatment with NOAs could cause unjustified risks for patients and also a possible future underuse of good drugs. For these reasons the vigilance must be high and ACs can have a crucial role in defining which is the best management for NOA patients and how to do it, as it happened for AVKs.

  4. Mitogen activated protein kinases: a role in inflammatory bowel disease?

    DEFF Research Database (Denmark)

    Broom, O J; Widjaya, B; Troelsen, J;

    2009-01-01

    Since their discovery more than 15 years ago, the mitogen activated protein kinases (MAPK) have been implicated in an ever-increasingly diverse array of pathways, including inflammatory signalling cascades. Inflammatory bowel diseases (IBD), such as ulcerative colitis and Crohn's disease, are...... their related signalling proteins in influencing the progression of IBD....

  5. Modeling of Raman optical activity of globular proteins

    Czech Academy of Sciences Publication Activity Database

    Kessler, Jiří; Kapitán, J.; Yamamoto, S.; Bouř, Petr

    Sapporo : Hokkaido University, 2015. s. 113. [International Conference on Chiroptical Spectroscopy /15./. 30.08.2015-03.09.2015, Sapporo] Institutional support: RVO:61388963 Keywords : vibrational optical activity * proteins * quantum chemistry Subject RIV: CF - Physical ; Theoretical Chemistry

  6. Vitamin K requirement in Danish anticoagulant-resistant Norway rats (Rattus norvegicus)

    DEFF Research Database (Denmark)

    Markussen, Mette D.; Heiberg, Ann-Charlotte; Nielsen, Robert;

    2003-01-01

    Norway rats, Rattus norvegicus, Denmark, anticoagulant rodenticide resistance, vitamin K requirement......Norway rats, Rattus norvegicus, Denmark, anticoagulant rodenticide resistance, vitamin K requirement...

  7. Antibodies for detecting and quantifying anticoagulant agents

    OpenAIRE

    Salvador, Juan Pablo; Marco, María Pilar

    2012-01-01

    [EN] The present invention relates to the design of haptens that are structurally related to coumarin oral anticoagulant compounds (COAC), to be used for the production of specific antibodies against said type of substances and the subsequent use thereof for the development of diagnosis tools for use in laboratories or in point-of-care (PoC) devices. In particular, the produced antibodies have been used to develop a diagnosis tool that enables the plasma levels of COAC to be quantified in pat...

  8. Shortfalls using second-generation anticoagulant rodenticides.

    Science.gov (United States)

    Borst, G H A; Counotte, G H M

    2002-03-01

    Second-generation anticoagulant rodenticides can give rise to unexpected casualties in nontarget species in zoos. The first two offspring of a pair of turkey vultures (Cathartes aura) died of brodifacoum toxicosis. The adult birds fed rodenticide-killed mice to their offspring. There are previous case reports of small carnivorous birds (Dacelo novae-guinae and Tockus deckeni) killed eating poisoned (difenacoum and brodifacoum) mice. Even a granivorous species (Rollulus roulroul) died, probably by contamination of its food by cockroaches that transported the rodenticide. PMID:12216801

  9. Dietary Protein Considerations to Support Active Aging

    OpenAIRE

    Wall, Benjamin T.; Cermak, Naomi M.; van Loon, Luc J. C.

    2014-01-01

    Given our rapidly aging world-wide population, the loss of skeletal muscle mass with healthy aging (sarcopenia) represents an important societal and public health concern. Maintaining or adopting an active lifestyle alleviates age-related muscle loss to a certain extent. Over time, even small losses of muscle tissue can hinder the ability to maintain an active lifestyle and, as such, contribute to the development of frailty and metabolic disease. Considerable research focus has addressed the ...

  10. Clinical and economic effectiveness of an inpatient anticoagulation service.

    Science.gov (United States)

    Mamdani, M M; Racine, E; McCreadie, S; Zimmerman, C; O'Sullivan, T L; Jensen, G; Ragatzki, P; Stevenson, J G

    1999-09-01

    We conducted a prospective cohort study to evaluate clinical and economic end points achieved by a pharmacist-managed anticoagulation service compared with usual care (50 patients/group). The primary therapeutic end point was the time between starting heparin therapy and surpassing the activated partial thromboplastin time therapeutic threshold. The primary economic end point was the direct variable cost of hospitalization from admission to discharge. No significant differences between groups were noted for the primary therapeutic end point. Total hospital costs were significantly lower for patients receiving pharmacist-managed care than for those receiving usual care ($1594 and $2014, respectively, 1997 dollars, p=0.04). Earlier start of warfarin (p=0.05) and shorter hospital stay (5 and 7 days, p=0.05) were associated with the pharmacist-managed group. PMID:10610013

  11. Desmolaris, a novel factor XIa anticoagulant from the salivary gland of the vampire bat (Desmodus rotundus) inhibits inflammation and thrombosis in vivo.

    Science.gov (United States)

    Ma, Dongying; Mizurini, Daniella M; Assumpção, Teresa C F; Li, Yuan; Qi, Yanwei; Kotsyfakis, Michail; Ribeiro, José M C; Monteiro, Robson Q; Francischetti, Ivo M B

    2013-12-12

    The identity of vampire bat saliva anticoagulant remained elusive for almost a century. Sequencing the salivary gland genes from the vampire bat Desmodus rotundus identified Desmolaris as a novel 21.5-kDa naturally deleted (Kunitz 1-domainless) form of tissue factor pathway inhibitor. Recombinant Desmolaris was expressed in HEK293 cells and characterized as a slow, tight, and noncompetitive inhibitor of factor (F) XIa by a mechanism modulated by heparin. Desmolaris also inhibits FXa with lower affinity, independently of protein S. In addition, Desmolaris binds kallikrein and reduces bradykinin generation in plasma activated with kaolin. Truncated and mutated forms of Desmolaris determined that Arg32 in the Kunitz-1 domain is critical for protease inhibition. Moreover, Kunitz-2 and the carboxyl-terminus domains mediate interaction of Desmolaris with heparin and are required for optimal inhibition of FXIa and FXa. Notably, Desmolaris (100 μg/kg) inhibited FeCl3-induced carotid artery thrombus without impairing hemostasis. These results imply that FXIa is the primary in vivo target for Desmolaris at antithrombotic concentrations. Desmolaris also reduces the polyphosphate-induced increase in vascular permeability and collagen- and epinephrine-mediated thromboembolism in mice. Desmolaris emerges as a novel anticoagulant targeting FXIa under conditions in which the coagulation activation, particularly the contact pathway, plays a major pathological role. PMID:24159172

  12. New anticoagulants for the prevention of venous thromboembolism

    Directory of Open Access Journals (Sweden)

    Cecilia Becattini

    2010-04-01

    Full Text Available Cecilia Becattini, Alessandra Lignani, Giancarlo AgnelliInternal and Cardiovascular Medicine and Stroke Unit, University of Perugia, ItalyAbstract: Anticoagulant drugs have an essential role in the prevention and treatment of thromboembolic diseases. Currently available anticoagulants substantially reduce the incidence of thromboembolic events in a number of clinical conditions. However, these agents have limitations that strengthen the case for the development of new anticoagulants. An ideal anticoagulant should be at least as effective as those currently in use, as well as safe, simple to use, and widely applicable. The majority of new anticoagulants currently under investigation are small molecules with a selective and direct anti-Xa or antithrombin action, allowing oral administration in fixed doses. These new agents are in different phases of clinical development. The anti-Xa agent rivaroxaban and the antithrombin agent dabigatran are already available for the prophylaxis of venous thromboembolism in some countries. Apixaban is in an advanced phase of clinical development and several anti-Xa agents are currently approaching phase III clinical trials. Promising results in terms of efficacy and safety profiles have been obtained with these agents in different clinical conditions. Differences in pharmacokinetics and pharmacodynamics could offer the potential for individualized anticoagulant therapies in the near future.Keywords: anticoagulant therapy, antithrombotic therapy, anticoagulants, direct thrombin inhibitors, factor Xa inhibitors

  13. Clinical considerations of anticoagulation therapy for patients with atrial fibrillation

    Institute of Scientific and Technical Information of China (English)

    Shu ZHANG

    2012-01-01

    Atrial fibrillation (AF) increases the risk of stroke.New anticoagulation agents have recently provided alternative and promising approaches.This paper reviews the current state of anticoagulation therapy in AF patients,focusing on various clinical scenarios and on comparisons,where possible,between western and eastern populations.

  14. Effects of computer-assisted oral anticoagulant therapy

    DEFF Research Database (Denmark)

    Rasmussen, Rune Skovgaard; Corell, Pernille; Madsen, Poul;

    2012-01-01

    UNLABELLED: BACKGROUND: Computer-assistance and self-monitoring lower the cost and may improve the quality of anticoagulation therapy. The main purpose of this clinical investigation was to use computer-assisted oral anticoagulant therapy to improve the time to reach and the time spent within the...

  15. Protein kinase activity associated with the nuclear lamina.

    OpenAIRE

    Dessev, G; Iovcheva, C; Tasheva, B; R. Goldman

    1988-01-01

    A nuclear lamina-enriched fraction from Ehrlich ascites tumor cells contains a tightly bound protein kinase activity, which phosphorylates in vitro the nuclear lamins, a 52-kilodalton protein, and several unknown minor components. The enzyme(s) is thermolabile, independent of Ca2+ and cAMP, and inhibited by quercetin. After treatment with 4 M urea it remains bound to the nuclear lamina in an active state, but it is irreversibly inactivated in 6 M urea. The lamin proteins are phosphorylated on...

  16. Stress-induced activation of protein kinase CK2 by direct interaction with p38 mitogen-activated protein kinase

    DEFF Research Database (Denmark)

    Sayed, M; Kim, S O; Salh, B S;

    2000-01-01

    Protein kinase CK2 has been implicated in the regulation of a wide range of proteins that are important in cell proliferation and differentiation. Here we demonstrate that the stress signaling agents anisomycin, arsenite, and tumor necrosis factor-alpha stimulate the specific enzyme activity of CK2...

  17. Clinical impact of a pharmacist-led inpatient anticoagulation service: a review of the literature

    Directory of Open Access Journals (Sweden)

    Lee T

    2016-05-01

    Full Text Available Tiffany Lee, Erin Davis, Jason Kielly School of Pharmacy, Memorial University, St John's, NL, Canada Background: Anticoagulant therapies provide management options for potentially life-threatening thromboembolic conditions. They also carry significant safety risks, requiring careful consideration of medication dose, close monitoring, and follow-up. Inpatients are particularly at risk, considering the widespread use of anticoagulants in hospitals. This has prompted the introduction of safety goals for anticoagulants in Canada and the USA, which recommend increased pharmacist involvement to reduce patient harm. The goal of this review is to evaluate the efficacy and safety of pharmacist-led inpatient anticoagulation services compared to usual or physician-managed care. Methods: This narrative review includes articles identified through a literature search of PubMed, Embase, and International Pharmaceutical Abstracts databases, as well as hand searches of the references of relevant articles. Full publications of pharmacist-managed inpatient anticoagulation services were eligible if they were published in English and assessed clinical outcomes. Results: Twenty-six studies were included and further divided into two categories: 1 autonomous pharmacist-managed anticoagulation programs (PMAPs and 2 pharmacist recommendation. Pharmacist management of heparin and warfarin appears to result in improvements in some surrogate outcomes (international normalized ratio [INR] stability and time in INR goal range, while results for others are mixed (time to therapeutic INR, length of stay, and activated partial thromboplastin time [aPTT] measures. There is also some indication that PMAPs may be associated with reduced patient mortality. When direct thrombin inhibitors are managed by pharmacists, there seems to be a shorter time to therapeutic aPTT and a greater percentage of time in the therapeutic range, as well as a decrease in the frequency of medication

  18. Antithrombin inhibits bronchoalveolar activation of coagulation and limits lung injury during Streptococcus pneumoniae pneumonia in rats

    NARCIS (Netherlands)

    Choi, Goda; Hofstra, Jorrit-Jan H; Roelofs, Joris J T H; Rijneveld, Anita W; Bresser, Paul; van der Zee, Jaring S; Florquin, Sandrine; van der Poll, Tom; Levi, Marcel; Schultz, Marcus J

    2008-01-01

    OBJECTIVE: Alveolar fibrin deposition is a hallmark of pneumonia. It has been proposed that natural inhibitors of coagulation, including activated protein C, antithrombin, and tissue factor pathway inhibitor, exert lung-protective effects via anticoagulant and possibly anti-inflammatory pathways. We

  19. Novel oral anticoagulants in the management of coronary artery disease.

    Science.gov (United States)

    McMahon, Sean R; Brummel-Ziedins, Kathleen; Schneider, David J

    2016-08-01

    Despite advances in interventional and pharmacologic therapy, survivors of myocardial infarction remain at an increased risk of subsequent cardiovascular events. Initial pharmacological management includes both platelet inhibition and parenteral anticoagulation, whereas long-term pharmacological therapy relies on antiplatelet therapy for prevention of thrombotic complications. Biomarkers showing ongoing thrombin generation after acute coronary syndromes suggest that anticoagulants may provide additional benefit in reducing cardiovascular events. We review the pharmacokinetics of novel anticoagulants, clinical trial results, the role of monitoring, and future directions for the use of novel oral anticoagulants in the treatment of coronary artery disease. Clinical trials have shown that long-term use of oral anticoagulants decreases the risk of cardiovascular events, but they do so at a cost of an increased risk of bleeding. Future studies will need to identify optimal treatment combinations for selected patients and conditions that address both the appropriate combination of therapy and the appropriate dosage of each agent when used in combination. PMID:27228186

  20. Intracranial hemorrhage in cancer patients treated with anticoagulation.

    Science.gov (United States)

    Weinstock, Matthew J; Uhlmann, Erik J; Zwicker, Jeffrey I

    2016-04-01

    Both venous thromboembolism and intracranial metastases are common complications in the setting of primary brain tumors and metastatic malignancies. Anticoagulation is indicated in the presence of cancer-associated thrombosis in order to limit the risk of pulmonary embolism; however, there is reluctance to initiate anticoagulation in the setting of intracranial metastatic disease due to potential for intracranial hemorrhage. Recent evidence suggests that therapeutic anticoagulation can be safely administered in the setting of metastatic brain tumors. This review examines the current understanding of the pathophysiology of intracranial hemorrhage in malignancy, describes the incidence of intracranial hemorrhage in the setting of brain tumors with therapeutic anticoagulation, and outlines management strategies relevant to the treatment of intracranial hemorrhage in the setting of anticoagulation. PMID:27067980

  1. New anticoagulants for the treatment of venous thromboembolism

    Directory of Open Access Journals (Sweden)

    Caio Julio Cesar dos Santos Fernandes

    2016-04-01

    Full Text Available Worldwide, venous thromboembolism (VTE is among the leading causes of death from cardiovascular disease, surpassed only by acute myocardial infarction and stroke. The spectrum of VTE presentations ranges, by degree of severity, from deep vein thrombosis to acute pulmonary thromboembolism. Treatment is based on full anticoagulation of the patients. For many decades, it has been known that anticoagulation directly affects the mortality associated with VTE. Until the beginning of this century, anticoagulant therapy was based on the use of unfractionated or low-molecular-weight heparin and vitamin K antagonists, warfarin in particular. Over the past decades, new classes of anticoagulants have been developed, such as factor Xa inhibitors and direct thrombin inhibitors, which significantly changed the therapeutic arsenal against VTE, due to their efficacy and safety when compared with the conventional treatment. The focus of this review was on evaluating the role of these new anticoagulants in this clinical context.

  2. [New anticoagulants in the treatment of venous thromboembolism].

    Science.gov (United States)

    Bura-Rivière, Alessandra

    2013-09-01

    Anticoagulant therapy is the cornerstone of treatment of venous thromboembolism (VTE). The treatment needs rapid initial anticoagulaton to minimize the risk of thrombus extension and fata pulmonary embolism, followed by an extended anticoagulation, aimed at preventing recurrent VTE. Till very recently, immediate anticoagulation can only be achieved with parenteral agents, such as heparin, low-molecular-weight heparin, or fondaparinux. Extended treatment usually involves the administration of vitamin K antagonists, such as warfarin. Emerging direct oral anticoagulants have the potential to streamline VTE treatment. These agents include oral anticoagulants that target thrombin or factor Xa. This article reviews the characteristics of these agents, describes the results of clinical trials in venous thromboembolic disease and outlines their strengths and weakness. PMID:24167902

  3. The treatment of venous thromboembolism with new oral anticoagulants

    Directory of Open Access Journals (Sweden)

    Davide Imberti

    2013-12-01

    Full Text Available Traditional anticoagulants, such as low molecular weight heparin, unfractionated heparin, fondaparinux and vitamin K antagonists, have been the mainstay of treatment of venous thromboembolism (VTE in the clinical hospital setting and after discharge. These anticoagulants are effective, but are associated with some limitations that may lead to their underuse in many settings. Based on the results of large, randomized clinical trials, new oral anticoagulants have been validated for the treatment of acute deep vein thrombosis and pulmonary embolism, and for the prevention of recurrent VTE. These drugs represent a landmark shift in anticoagulation care and may overcome some of the limitations of traditional agents, with the potential of improving adherence to anticoagulation therapy.

  4. C-Reactive Protein Activates Complement in Infarcted Human Myocardium

    OpenAIRE

    Nijmeijer, Remco; Lagrand, Wim K.; Lubbers, Yvonne T. P.; Visser, Cees A.; Meijer, Chris J.L.M.; Niessen, Hans W. M.; Hack, C. Erik

    2003-01-01

    Circulating levels of C-reactive protein (CRP) constitute a cardiovascular risk marker. Immunohistochemical studies have revealed co-localization of CRP and activated complement in human infarcted myocardium suggesting CRP to enhance inflammation in ischemic myocardium by inducing local complement activation. The aim was to establish whether CRP activates complement in infarcted human myocardium and to assess the relationship between this activation and the duration of infarction. Myocardial ...

  5. Depletion of WRN protein causes RACK1 to activate several protein kinase C isoforms

    DEFF Research Database (Denmark)

    Massip, L; Garand, C; Labbé, A;

    2010-01-01

    show that a knock down of the WRN protein in normal human fibroblasts induces phosphorylation and activation of several protein kinase C (PKC) enzymes. Using a tandem affinity purification strategy, we found that WRN physically and functionally interacts with receptor for activated C-kinase 1 (RACK1...... contrast, different DNA-damaging treatments known to activate PKCs did not induce RACK1/PKCs association in cells. Overall, our results indicate that a depletion of the WRN protein in normal fibroblasts causes the activation of several PKCs through translocation and association of RACK1 with such kinases.......Werner's syndrome (WS) is a rare autosomal disease characterized by the premature onset of several age-associated pathologies. The protein defective in patients with WS (WRN) is a helicase/exonuclease involved in DNA repair, replication, transcription and telomere maintenance. In this study, we...

  6. [The practice guideline 'Neuraxis blockade and anticoagulation'].

    Science.gov (United States)

    De Lange, J J; Van Kleef, J W; Van Everdingen, J J E

    2004-07-31

    In a patient with a coagulation disorder, the administration of a local anaesthetic by means of a needle or via the insertion of a catheter into the epidural space or spinal cavity may lead to bleeding and haematoma formation, with a danger of pressure on the spinal cord or nerve roots. Employing the method of the Dutch Institute for Healthcare (CBO) for the development of practice guidelines, a working group of anaesthesiologists, a haematologist and a hospital chemist have drawn up recommendations for neuraxis blockade in combination with anticoagulant therapy. In patients with a clinically acquired tendency toward increased bleeding, the management is highly dependent on the cause of the bleeding tendency. If the patient uses acetylsalicylic acid or clopidogrel, the medication must be withdrawn at least 10 days before neuraxis blockade is started. Therapy with glycoprotein-IIb/IIIa-receptor antagonists is an absolute contra-indication for neuraxis blockade. In patients who are using coumarin derivatives, neuraxis blockade results in an increased risk of a neuraxial haematoma. The coumarin derivative should then be withdrawn and replaced by a different form of anticoagulation. The use of low-molecular-weight heparin at the usual prophylactic dosage is not a contra-indication for neuraxis blockade and the risk of a neuraxial haematoma following neuraxis blockade is also not increased significantly by the subcutaneous administration of unfractionated heparin. PMID:15366721

  7. Regulatory crosstalk by protein kinases on CFTR trafficking and activity

    Science.gov (United States)

    Farinha, Carlos Miguel; Swiatecka-Urban, Agnieszka; Brautigan, David; Jordan, Peter

    2016-01-01

    Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) is a member of the ATP binding cassette (ABC) transporter superfamily that functions as a cAMP-activated chloride ion channel in fluid-transporting epithelia. There is abundant evidence that CFTR activity (i.e. channel opening and closing) is regulated by protein kinases and phosphatases via phosphorylation and dephosphorylation. Here, we review recent evidence for the role of protein kinases in regulation of CFTR delivery to and retention in the plasma membrane. We review this information in a broader context of regulation of other transporters by protein kinases because the overall functional output of transporters involves the integrated control of both their number at the plasma membrane and their specific activity. While many details of the regulation of intracellular distribution of CFTR and other transporters remain to be elucidated, we hope that this review will motivate research providing new insights into how protein kinases control membrane transport to impact health and disease.

  8. Polissacarídeos sulfatados isolados das clorofíceas Caulerpa racemosa e Caulerpa cupressoides – extração, fracionamento e atividade anticoagulante =Sulfated polysaccharides isolated from Caulerpa racemosa and Caulerpa cupressoides (Chlorophyceaes – extraction, fractionation and anticoagulant activity

    Directory of Open Access Journals (Sweden)

    José Ariévilo Gurgel Rodrigues

    2010-04-01

    in 0.1 M sodium acetate buffer (pH 5.0 containing 5 mM cysteine and 5 mM EDTA, followed by fractionation on ion exchange DEAE-cellulose column with NaCl gradient. The obtained fractions were analyzed by 0.5% agarose gel electrophoresis and the anticoagulant activity measured by the activated partial thromboplastin time (APTT using normal human plasma, and compared to a standard heparin curve (193 IU mg-1. Similar chromatographic profiles of SP were shown on both species, butwith distinct mobility patterns, when the SP fractions were compared by electrophoresis. SP eluted with 0.75 M of NaCl modified the APTT, whose anticoagulant activities were only 21.23 and 24.36 IU mg-1 for C. racemosa and C. cupressoides, respectively. Therefore, anticoagulant SP isolated from chlorophyceaes showed effects inferior to heparin, and comparative studies of these molecules are also suggested as auxiliary tools in the identification of algae of the same genus.

  9. Multistep Phosphorelay Proteins Transmit Oxidative Stress Signals to the Fission Yeast Stress-activated Protein Kinase

    OpenAIRE

    Nguyen, Aaron Ngocky; Lee, Albert; Place, Warren; Shiozaki, Kazuhiro

    2000-01-01

    In response to oxidative stress, eukaryotic cells induce transcription of genes required for detoxification of oxidants. Here we present evidence that oxidative stress stimuli are transmitted by a multistep phosphorelay system to the Spc1/Sty1 stress-activated protein kinase in the fission yeast Schizosaccharomyces pombe. The fission yeast mpr1+ gene encodes a novel protein with a histidine-containing phosphotransfer domain homologous to the budding yeast Ypd1. Spc1 activation upon oxidative ...

  10. Cellular reprogramming through mitogen-activated protein kinases

    Directory of Open Access Journals (Sweden)

    Justin eLee

    2015-10-01

    Full Text Available Mitogen-activated protein kinase (MAPK cascades are conserved eukaryote signaling modules where MAPKs, as the final kinases in the cascade, phosphorylate protein substrates to regulate cellular processes. While some progress in the identification of MAPK substrates has been made in plants, the knowledge on the spectrum of substrates and their mechanistic action is still fragmentary. In this focused review, we discuss the biological implications of the data in our original paper (Sustained mitogen-activated protein kinase activation reprograms defense metabolism and phosphoprotein profile in Arabidopsis thaliana; Frontiers in Plant Science 5: 554 in the context of related research. In our work, we mimicked in vivo activation of two stress-activated MAPKs, MPK3 and MPK6, through transgenic manipulation of Arabidopsis thaliana and used phosphoproteomics analysis to identify potential novel MAPK substrates. Here, we plotted the identified putative MAPK substrates (and downstream phosphoproteins as a global protein clustering network. Based on a highly stringent selection confidence level, the core networks highlighted a MAPK-induced cellular reprogramming at multiple levels of gene and protein expression – including transcriptional, post-transcriptional, translational, post-translational (such as protein modification, folding and degradation steps, and also protein re-compartmentalization. Additionally, the increase in putative substrates/phosphoproteins of energy metabolism and various secondary metabolite biosynthesis pathways coincides with the observed accumulation of defense antimicrobial substances as detected by metabolome analysis. Furthermore, detection of protein networks in phospholipid or redox elements suggests activation of downstream signaling events. Taken in context with other studies, MAPKs are key regulators that reprogram cellular events to orchestrate defense signaling in eukaryotes.

  11. Conserved interaction of the papillomavirus E2 transcriptional activator proteins with human and yeast TFIIB proteins.

    OpenAIRE

    Benson, J D; Lawande, R; Howley, P M

    1997-01-01

    Papillomavirus early gene expression is regulated by the virus gene-encoded E2 proteins. The best-characterized E2 protein, encoded by bovine papillomavirus type 1 (BPV-1), has been shown to interact with basal transcription factor IIB (TFIIB) and the TATA binding protein basal transcription factor (N. M. Rank and P. F. Lambert, J. Virol. 69:6323-6334, 1995). We demonstrate that the potent E2 transcriptional activator protein encoded by a gene of human PV type 16 also interacts with TFIIB in ...

  12. Contractions activate hormone-sensitive lipase in rat muscle by protein kinase C and mitogen-activated protein kinase

    DEFF Research Database (Denmark)

    Donsmark, Morten; Langfort, Jozef; Holm, Cecilia;

    2003-01-01

    contractions. Adrenaline acts via cAMP-dependent protein kinase (PKA). The signalling mediating the effect of contractions is unknown and was explored in this study. Incubated soleus muscles from 70 g male rats were electrically stimulated to perform repeated tetanic contractions for 5 min. The contraction......-induced activation of HSL was abolished by the protein kinase C (PKC) inhibitors bisindolylmaleimide I and calphostin C and reduced 50% by the mitogen-activated protein kinase kinase (MEK) inhibitor U0126, which also completely blocked extracellular signal-regulated kinase (ERK) 1 and 2 phosphorylation. None of the...

  13. A conserved patch of hydrophobic amino acids modulates Myb activity by mediating protein-protein interactions.

    Science.gov (United States)

    Dukare, Sandeep; Klempnauer, Karl-Heinz

    2016-07-01

    The transcription factor c-Myb plays a key role in the control of proliferation and differentiation in hematopoietic progenitor cells and has been implicated in the development of leukemia and certain non-hematopoietic tumors. c-Myb activity is highly dependent on the interaction with the coactivator p300 which is mediated by the transactivation domain of c-Myb and the KIX domain of p300. We have previously observed that conservative valine-to-isoleucine amino acid substitutions in a conserved stretch of hydrophobic amino acids have a profound effect on Myb activity. Here, we have explored the function of the hydrophobic region as a mediator of protein-protein interactions. We show that the hydrophobic region facilitates Myb self-interaction and binding of the histone acetyl transferase Tip60, a previously identified Myb interacting protein. We show that these interactions are affected by the valine-to-isoleucine amino acid substitutions and suppress Myb activity by interfering with the interaction of Myb and the KIX domain of p300. Taken together, our work identifies the hydrophobic region in the Myb transactivation domain as a binding site for homo- and heteromeric protein interactions and leads to a picture of the c-Myb transactivation domain as a composite protein binding region that facilitates interdependent protein-protein interactions of Myb with regulatory proteins. PMID:27080133

  14. Organization, Structure and Activity of Proteins in Monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Boucher,J.; Trudel, E.; Methot, M.; Desmeules, P.; Salesse, C.

    2007-01-01

    Many different processes take place at the cell membrane interface. Indeed, for instance, ligands bind membrane proteins which in turn activate peripheral membrane proteins, some of which are enzymes whose action is also located at the membrane interface. Native cell membranes are difficult to use to gain information on the activity of individual proteins at the membrane interface because of the large number of different proteins involved in membranous processes. Model membrane systems, such as monolayers at the air-water interface, have thus been extensively used during the last 50 years to reconstitute proteins and to gain information on their organization, structure and activity in membranes. In the present paper, we review the recent work we have performed with membrane and peripheral proteins as well as enzymes in monolayers at the air-water interface. We show that the structure and orientation of gramicidin has been determined by combining different methods. Furthermore, we demonstrate that the secondary structure of rhodopsin and bacteriorhodopsin is indistinguishable from that in native membranes when appropriate conditions are used. We also show that the kinetics and extent of monolayer binding of myristoylated recoverin is much faster than that of the nonmyristoylated form and that this binding is highly favored by the presence polyunsaturated phospholipids. Moreover, we show that the use of fragments of RPE65 allow determine which region of this protein is most likely involved in membrane binding. Monomolecular films were also used to further understand the hydrolysis of organized phospholipids by phospholipases A2 and C.

  15. Anthelmintic activity of Leucaena leucocephala protein extracts on Haemonchus contortus.

    Science.gov (United States)

    Soares, Alexandra Martins dos Santos; de Araújo, Sandra Alves; Lopes, Suzana Gomes; Costa Junior, Livio Martins

    2015-01-01

    The objective of this study was to evaluate the effects of protein extracts obtained from the plant Leucaena leucocephala on the nematode parasite Haemonchus contortus. The seeds, shell and cotyledon of L. leucocephala were separated and their proteins extracted using a sodium phosphate buffer, and named as TE (total seed extract), SE (shell extract) and CE (cotyledon extract). Soluble protein content, protease, protease inhibitory and chitinase activity assays were performed. Exsheathment inhibition of H. contortus larvae were performed at concentrations of 0.6 mg mL-1, and egg hatch assays were conducted at protein concentrations of 0.8, 0.4, 0.2, 0.1 and 0.05 mg mL-1. The effective concentration for 50% hatching inhibition (EC50) was estimated by probit. Different proportions of soluble proteins, protease and chitinase were found in TE and CE. Protease inhibitory activity was detected in all extracts. The EC50 of the CE and TE extracts were 0.48 and 0.33 mg mL-1, respectively. No ovicidal effects on H. contortus were detected in SE extracts, and none of the protein extracts demonstrated larvicidal effects on H. contortus. We therefore conclude that protein extracts of L. leucocephala had a detrimental effect on nematode eggs, which can be correlated with the high protease and chitinase activity of these extracts. PMID:26689178

  16. G protein activation stimulates phospholipase D signaling in plants

    NARCIS (Netherlands)

    Munnik, T.; Arisz, S.A.; Vrije, de T.; Musgrave, A.

    1995-01-01

    We provide direct evidence for phospholipase D (PLD) signaling in plants by showing that this enzyme is stimulated by the G protein activators mastoparan, ethanol, and cholera toxin. An in vivo assay for PLD activity in plant cells was developed based on the use of a "reporter alcohol" rather than w

  17. Activation of repair and checkpoints by double-strand breaks of DNA. Activational cascade of protein phosphorylation

    International Nuclear Information System (INIS)

    Molecular mechanisms of double-strand breaks repair and checkpoints include phosphorylations of repair and checkpoint-proteins by protein kinases. Chemical modification of proteins has different consequences including activation, changing of affinity to proteins and localization

  18. Exactin: A specific inhibitor of Factor X activation by extrinsic tenase complex from the venom of Hemachatus haemachatus.

    Science.gov (United States)

    Girish, Vallerinteavide Mavelli; Kini, R Manjunatha

    2016-01-01

    Unwanted clots lead to heart attack and stroke that result in a large number of deaths. Currently available anticoagulants have some drawbacks including their non-specific actions. Therefore novel anticoagulants that target specific steps in the coagulation pathway are being sought. Here we describe the identification and characterization of a novel anticoagulant protein from the venom of Hemachatus haemachatus (African Ringhals cobra) that specifically inhibits factor X (FX) activation by the extrinsic tenase complex (ETC) and thus named as exactin. Exactin belongs to the three-finger toxin (3FTx) family, with high sequence identity to neurotoxins and low identity to the well-characterized 3FTx anticoagulants-hemextin and naniproin. It is a mixed-type inhibitor of ETC with the kinetic constants, Ki' and Ki determined as 30.62 ± 7.73 nM and 153.75 ± 17.96 nM, respectively. Exactin does not bind to the active site of factor VIIa and factor Xa based on its weak inhibition (IC50 ≫ 300 μM) to the amidolytic activities of these proteases. Exactin shows exquisite macromolecular specificity to FX activation as compared to factor IX activation by ETC. Exactin thus displays a distinct mechanism when compared to other anticoagulants targeting ETC, with its selective preference to ETC-FX [ES] complex. PMID:27558950

  19. Enhancing anticoagulation and endothelial cell proliferation of titanium surface by sequential immobilization of poly(ethylene glycol) and collagen

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Chang-Jiang, E-mail: swjtupcj@163.com; Hou, Yan-Hua; Ding, Hong-Yan; Dong, Yun-Xiao

    2013-12-15

    In the present study, poly(ethylene glycol) (PEG) and collagen I were sequentially immobilized on the titanium surface to simultaneously improve the anticoagulation and endothelial cell proliferation. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy analysis confirmed that PEG and collagen I were successfully immobilized on the titanium surface. Water contact angle results suggested the excellent hydrophilic surface after the immobilization. The anticoagulation experiments demonstrated that the immobilized PEG and collagen I on the titanium surface could not only obviously prevent platelet adhesion and aggregation but also prolong activated partial thromboplastin time (APTT), leading to the improved blood compatibility. Furthermore, immobilization of collagen to the end of PEG chain did not abate the anticoagulation. As compared to those on the pristine and PEG-modified titanium surfaces, endothelial cells exhibited improved proliferative profiles on the surface modified by the sequential immobilization of PEG and collagen in terms of CCK-8 assay, implying that the modified titanium may promote endothelialization without abating the blood compatibility. Our method may be used to modify the surface of blood-contacting biomaterials such as titanium to promote endothelialization and improve the anticoagulation, it may be helpful for development of the biomedical devices such as coronary stents, where endothelializaton and excellent anticoagulation are required.

  20. Gc protein (vitamin D-binding protein): Gc genotyping and GcMAF precursor activity.

    Science.gov (United States)

    Nagasawa, Hideko; Uto, Yoshihiro; Sasaki, Hideyuki; Okamura, Natsuko; Murakami, Aya; Kubo, Shinichi; Kirk, Kenneth L; Hori, Hitoshi

    2005-01-01

    The Gc protein (human group-specific component (Gc), a vitamin D-binding protein or Gc globulin), has important physiological functions that include involvement in vitamin D transport and storage, scavenging of extracellular G-actin, enhancement of the chemotactic activity of C5a for neutrophils in inflammation and macrophage activation (mediated by a GalNAc-modified Gc protein (GcMAF)). In this review, the structure and function of the Gc protein is focused on especially with regard to Gc genotyping and GcMAF precursor activity. A discussion of the research strategy "GcMAF as a target for drug discovery" is included, based on our own research. PMID:16302727

  1. Structure versus anticoagulant and antithrombotic actions of marine sulfated polysaccharides

    Directory of Open Access Journals (Sweden)

    Vitor Hugo Pomin

    2012-08-01

    Full Text Available Marine sulfated polysaccharides (MSP, such as sulfated fucans (SF, sulfated galactans (SG and glycosaminoglycans (GAG isolated from either algae or invertebrate animals, are highly anionic polysaccharides capable of interacting with certain cationic proteins, such as (co-factors of the coagulation cascade during clotting-inhibition processes. These molecular complexes between MSP and coagulation-related proteins might, at first glance, be assumed to be driven mostly by electrostatic interactions. However, a systematic comparison using several novel sulfated polysaccharides composed of repetitive oligosaccharides with clear sulfation patterns has shown that these molecular interactions are regulated essentially by the stereochemistry of the glycans (which depends on a conjunction of anomericity, monosaccharide, conformational preference, and glycosylation and sulfation sites, rather than just a simple consequence of their negative charge density (mainly the number of sulfate groups. Here, we present an overview of the structure-function relationships of MSP, correlating their structures with their potential anticoagulant and antithrombotic actions, since pathologies related to the cardiovascular system are one of the major causes of illness and mortality in the world.

  2. Heated Proteins are Still Active in a Functionalized Nanoporous Support

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Baowei; Qi, Wen N.; Li, Xiaolin; Lei, Chenghong; Liu, Jun

    2013-07-08

    We report that even under the heated condition, the conformation and activity of a protein can be hoarded in a functionalized nanoporous support via non-covalent interaction, although the hoarded protein was not exhibiting the full protein activity, the protein released subsequently still maintained its native conformation and activity. Glucose oxidase (GOX) was spontaneously and largely entrapped in aminopropyl-functionalized mesoporous silica (NH2-FMS) at 20 oC via a dominant electrostatic interaction. Although FMS-GOX displayed 45% activity of the free enzyme in solution, the GOX released from FMS exhibited its 100% activity prior to the entrapment. Surprisingly, the released GOX from FMS still maintained 89% of its initial activity prior to the entrapment after FMS-GOX was incubated at 60 oC for 1 h prior to release, while the free GOX in solution lost nearly all activity under the same incubation. Intrinsic fluorescence emission of GOX and native electrophoresis demonstrated that the heating resulted in significant conformational changes and oligomeric structures of the free GOX, but FMS efficiently maintained the thermal stability of GOX therein and resisted the thermal denaturation and oligomeric aggregation.

  3. Management of antiplatelet and anticoagulant therapy for endoscopic procedures: introduction to novel oral anticoagulants

    Directory of Open Access Journals (Sweden)

    Martha L. González-Bárcenas

    2016-02-01

    Full Text Available The development of novel antithrombotic therapy in the past few years and its prescription in patients with cardiovascular and circulatory disease has widened the spectrum of drugs that need to be considered when performing an endoscopic procedure. The balance between the thrombotic risk patients carry due to their medical history and the bleeding risk involved in endoscopic procedures should be thoroughly analyzed by Gastroenterologists. New oral anticoagulants (NOACs impose an additional task. These agents, that specifically target factor IIa or Xa, do not dispose of an anticoagulation monitoring method nor have an antidote to revert their effect, just as with antiplatelet agents. Understanding the fundamental aspects of these drugs provides the necessary knowledge to determine the ideal period the antithrombotic therapy should be interrupted in order to perform the endoscopic procedure, offering maximum safety for patients and optimal results.

  4. Evaluation of the Effect of Lime Fruit Juice on the Anticoagulant Effect of Warfarin

    Science.gov (United States)

    Adepoju, GKA; Adeyemi, T

    2010-01-01

    Aim: Citrus aurantifolia (Family Rutaceae) is commonly known as a familiar food and medicine, and s therapeutic effectiveness in a variety of diseases has been suggested in traditional medicine. Various complementary and alternative medicines (CAM) have been shown to interact with orthodox medicines. Hence, the aim of this study is to investigate such a phenomenon particularly the interaction of lime fruit juice with warfarin. Materials and Method: Wistar strain albino rats of both sexes weighing between 190 and 230g were administered with oral doses of the respective drugs used depending on the groups of animals. Effects on the anticoagulant activity of warfarin were determined by standard laboratory methods. Result: Lime fruit juice caused a reduction in the anticoagulant activity of warfarin. Conclusion: This finding has shown that CAM can interact with orthodox medicines hence, warfarin prescribers need to be aware of the usage of CAM and monitor the international normalized ratio (INR) of their patients more frequently. PMID:21042484

  5. Redox Regulation of the AMP-Activated Protein Kinase

    OpenAIRE

    Yingying Han; Qilong Wang; Ping Song; Yi Zhu; Ming-Hui Zou

    2010-01-01

    Redox state is a critical determinant of cell function, and any major imbalances can cause severe damage or death. Objectives The aim of this study is to determine if AMP-activated protein kinase (AMPK), a cellular energy sensor, is activated by oxidants generated by Berberine in endothelial cells (EC). Methods Bovine aortic endothelial cells (BAEC) were exposed to Berberine. AMPK activity and reactive oxygen species were monitored after the incubation. Results In BAEC, Berberine caused a dos...

  6. Redox Regulation of Protein Tyrosine Phosphatase Activity by Hydroxyl Radical

    OpenAIRE

    Meng, Fan-Guo; Zhang, Zhong-Yin

    2012-01-01

    Substantial evidence suggests that transient production of reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) is an important signaling event triggered by the activation of various cell surface receptors. Major targets of H2O2 include protein tyrosine phosphatases (PTPs). Oxidation of the active site Cys by H2O2 abrogates PTP catalytic activity, thereby potentially furnishing a mechanism to ensure optimal tyrosine phosphorylation in response to a variety of physiological stimuli. ...

  7. Nanoencapsulation of Biologically Active Peptides from Whey Proteins

    Directory of Open Access Journals (Sweden)

    Sebnem Tellioglu Harsa

    2014-06-01

    Full Text Available "Now a days consumers, in order to feed with balanced diet, prefer healthy and reliable foods. In this respect food manufacturers are trying to respond the demands of consumers by developing new types of foods such as diet foods ( low calorie foods, modified foods (organic foods and functional foods (probiotic and prebiotics. Thus, production of nutritious, functional and beneficial foods has become a growing sector in the United States and European countries. Proteins are major source of many bioactive peptides. Bioactive peptides have been defined as specific protein fragments that have a positive impact on body functions and may ultimately influence human health. These peptides stay inactive within the main protein structure and activated by the enzymatic hydrolysis. These bioactive peptides, derived from proteins, are able to influence basic body systems (cardiovascular, nervous, gastrointestinal and immune systems and show multi-functional character. Due to these properties, studies have recently been focused on milk proteins and their bioactive peptides. Such peptides are inactive within the sequence of the milk protein. Whey contains a multitude of biologically active proteins and peptides. Physiologically active serum proteins are serum albumin, immunoglobulins, proteose-peptone, lactoferrin, lactoperoxidase and growth factors. In addition to these, enzymatic degradation of serum proteins releases a number of bioactive peptides such as alfa-lactophorin, beta-lactophorin, beta- lactotensin, lactokinin, albutensin, serophorin and lactoferricin. One of the common qualities of bioactive substances is their sensitivity to the physical and chemical properties of the environment. For this reason, the usefulness of bioactive components in food is limited by the structure. In order to sustain bioavailibility of these peptides, limiting its relationship with the media by encapsulation technology is one of them osthotly debated issues on in recent

  8. Protein determination in soya bean by fast neutron activation analysis

    International Nuclear Information System (INIS)

    For a non-destructive determination of the protein content in soya bean samples, 14-MeV neutron activation analysis was applied. To check the method, the results obtained by X-ray fluorescence analysis and the Kjeldahl procedure were compared. For pressed pellet samples of about 1 g with 15 min irradiation and 10 min measuring times the accuracy of the protein determination was found to be 15%. (author) 7 refs.; 4 figs.; 3 tabs

  9. Antioxidant and Anticoagulant Status Were Improved by Personalized Dietary Intervention Based on Biochemical and Clinical Parameters in Cancer Patients.

    Science.gov (United States)

    Lee, Ga-Yi; Lee, Jong Jyun; Lee, Seung-Min

    2015-01-01

    We investigated whether personalized dietary intervention could improve clinical measurements such as immune cell-mediated cytotoxicity, serum albumin, derivatives of reactive oxygen metabolites (D-ROMS), D-dimer, and fibrinogen. Cancer patients received either a treatment support diet (TD, for those with chemotherapy), or a remission support diet (RD; for those in remission) for at least 3 wk (21-61 days). Both diets were low glycemic, low fat, and high plant protein diets; the diet for the TD group contained an additional 0.5 servings of protein. Based on clinical values, additional amounts of garlic, onion, tomato, shiitake, rice bran, kale, blueberry, pineapples, and/or turmeric powder were provided in regular meals. Estimated daily intake of protein, plant fat, garlic, onion, allicin, and quercetin was greater in the TD compared to the RD. An increased intake of vitamin A, vitamin C, vitamin E and selenium and a reduction in D-dimer were noted compared to baseline diets in both groups. A decrease in D-ROMS in the RD and an increase in albumin and an increased tendency in cytotoxicity in the TD were observed. In conclusion, personalized diets with supplemented functional ingredients improved antioxidant status and/or anticoagulant activity in cancer patients undergoing chemotherapy and in remission. PMID:26333154

  10. Efficacy and safety of new oral anticoagulants in prophylaxis and treatment of venous thromboembolism

    OpenAIRE

    Luca Masotti; Cecilia Becattini; Roberto Cappelli; Giancarlo Landini; Alessandro Pampana; Domenico Prisco; Giancarlo Agnelli

    2011-01-01

    One of the main innovation emerged in recent years in the field of venous thromboembolism (VTE) has been represented by the clinical development and marketing of new oral anticoagulant agents used for prophylaxis and acute treatment. These drugs are represented by direct thrombin inhibitors (anti-factor IIa) and the direct inhibitors of activated factor X (anti-Xa). The main achievement of these new agents is represented by their ease of use without laboratory monitoring or dose adjustment. D...

  11. Pharmacodynamic parameters of anticoagulants based on sulfated polysaccharides from marine algae.

    Science.gov (United States)

    Drozd, N N; Tolstenkov, A S; Makarov, V A; Kuznetsova, T A; Besednova, N N; Shevchenko, N M; Zvyagintseva, T N

    2006-11-01

    Fucoidans isolated from Fucus evanescens and Laminaria cichorioides kelp can inhibit thrombin and factor Xa of the blood coagulation system. In rats, intravenous injection of fucoidans dose-dependently increased anticoagulant activity of the plasma. Fucoidans can form complexes with protamine sulfate. The observed quantitative differences in the action of fucoidans can result from different sulfation degree and the presence of various types of glycoside bonds in polysaccharide molecules. PMID:17415470

  12. Thromboembolism and anticoagulation after Fontan surgery.

    Science.gov (United States)

    Viswanathan, Sangeetha

    2016-01-01

    This review attempts to answer the common questions faced by a clinician regarding thromboembolism and thromboprophylaxis in patients following Fontan surgery. The review is in an easy to understand question and answer format and discusses the currently available literature on the subject in an attempt to arrive at practical clinically relevant solutions. Patients who have undergone the Fontan operation are at a high risk for thromboembolism. Based on available evidence, there is a strong rationale for thromboprophylaxis. However, it is not clear as to which agent should be administered to prevent thromboembolic events. While the available evidence suggests that antiplatelet agents alone may be as good as oral anticoagulants, there is a need for a large multicenter randomized control trial comparing these two common strategies to deliver a clear verdict. PMID:27625521

  13. Emerging Roles of AMP-Activated Protein Kinase

    DEFF Research Database (Denmark)

    Fritzen, Andreas Mæchel

    The cellular energy sensor AMP-activated protein kinase (AMPK) is activated, when the energy balance of the cell decreases. AMPK has been proposed to regulate multiple metabolic processes. However, much of the evidence for these general effects of AMPK relies on investigations in cell systems or...... exercise appears to inhibit pyruvate dehydrogenase (PDH) activity by an immediate up-regulation of pyruvate dehydrogenase kinase 4 (PDK4) protein content. Consequently, this may inhibit glucose oxidation and thereby generate conditions for increased FA oxidation and glycogen resynthesis in skeletal muscle...... importance for prioritising energy dissipation, inhibition of lipid storage pathways and regulation of mitochondrial and metabolic proteins, but this needs further investigations. In addition, we provide evidence that AMPK is regulating autophagic signalling in skeletal muscle. Thus, in skeletal muscle AMPK...

  14. Periablative Anticoagulation Strategies in Patients with Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Eduardo B. Saad

    2008-12-01

    Full Text Available Atrial fibrillation is associated with thromboembolic events that may cause important impairment on quality of life. Pulmonary vein isolation is the treatment of choice in cases that are refractory to medical therapy. Once sheaths and catheters are manipulated inside the left atrium, anticoagulation with heparin must be used during the procedure to protect patients from thromboembolic phenomena. Different strategies of anticoagulation are used at different centers. This review summarizes the pathophysiology of thrombus formation in the left atrium, defines which patients are under high risk and describes the main strategies used for anticoagulation.

  15. Patient survey of a pharmacist-managed anticoagulation clinic.

    Science.gov (United States)

    Lewis, S M; Kroner, B A

    1997-11-01

    The literature describing pharmacy involvement with anticoagulation services primarily does not include information about patients' perceptions of this involvement. A 22-question survey was developed and administered to 296 patients enrolled in the anticoagulation clinic at the VA Pittsburgh Health Care System. Excluded patients had fewer than four clinic visits or were followed outside of the anticoagulation clinic. The study period was nine weeks and any missed patients were telephoned. The median response to each question was determined. Similar questions were analyzed for acquiescent trends. Results indicate that, overall, patients are comfortable with pharmacists providing warfarin monitoring and dose adjustments. PMID:10174757

  16. Emergency management of patients being treated with oral anticoagulants

    Directory of Open Access Journals (Sweden)

    Franco Manzato

    2013-12-01

    Full Text Available Vitamin K antagonists (VKA are among the most widely prescribed drugs in the industrialized world. In fact, for decades, VKA have been the only orally available anticoagulant for the primary and secondary prevention of venous and arterial thrombotic events. Their efficacy has been widely demonstrated in a series of studies carried out in the 1990s. Since the incidences of atrial fibrillation and venous thromboembolism increase exponentially with age, the number of anticoagulated patients is destined to increase. This paper examines anticoagulation therapy management with particular attention to the use of VKA.

  17. Antioxidant activity of whey protein hydrolysates in milk beverage system.

    Science.gov (United States)

    Mann, Bimlesh; Kumari, Anuradha; Kumar, Rajesh; Sharma, Rajan; Prajapati, Kishore; Mahboob, Shaik; Athira, S

    2015-06-01

    The aim of the present study was to evaluate the antioxidant activity of flavoured milk enriched with antioxidative whey protein hydrolysates (WPHs) by radical scavenging method. Whey protein concentrate (WPC) was hydrolyzed by using three commercial proteases; flavouzyme, alcalase and corolase PP and these WPHs were analyzed for degree of hydrolysis and antioxidant activity. The antioxidant activities of these WPHs were evaluated using ABTS method. Trolox equivalent antioxidant activity of all the hydrolysates i.e. flavourzyme (0.81 ± 0.04), alcalase (1.16 ± 0.05) and corolase (1.42 ± 0.12) was higher than the WPC (0.19 ± 0.01). Among these, whey protein hydrolysates prepared using corolase showed maximum antioxidant activity. Total 15 β-lactoglobulin, 1 α-lactoalbumin, and 6 β-casein derived peptide fragments were identified in the WPHs by LC-MS/MS. Due to their size and characteristic amino acid composition, all the identified peptides may contribute for the antioxidant activity. The strawberry and chocolate flavoured milk was supplemented with WPC and WPHs and 2 % addition has shown increase in antioxidant activity upto 42 %. The result suggests that WPH could be used as natural biofunctional ingredients in enhancing antioxidant properties of food products. PMID:26028704

  18. Evaluation of a pharmacist-managed anticoagulation clinic: Improving patient care

    OpenAIRE

    Bungard, Tammy J; Gardner, Leslie; Archer, Stephen L.; Hamilton, Peter; Ritchie, Bruce; Tymchak, Wayne; Tsuyuki, Ross T.

    2009-01-01

    Background Anticoagulation management services (AMSs) are widely used for anticoagulation management in many countries. Our AMS is a pharmacist-run ambulatory clinic with a physician advisory committee that manages patients referred with complicated anticoagulation histories. This paper assesses the adequacy of anticoagulation, rates of anticoagulant-related events and associated health care resource utilization for patients before and after referral to our AMS. Methods Consecutive patients r...

  19. Antioxidant activity of Fish Protein Hydrolysates from Sardinella longiceps

    Directory of Open Access Journals (Sweden)

    JEEVITHA K

    2014-12-01

    Full Text Available Sardinella longiceps were hydrolysed with the different concentration of proteolytic enzymes trypsin to obtain peptides with antioxidant activity. The degree of hydrolysis and yield of hydrolysates were found increasing with increasing the concentration of enzyme. The antioxidant activities of hydrolysates were investigated through various assays. The hydrolysate exhibited the higher reducing power capability. The hydrolysates has shown a higher scavenging activity against DPPH, Superoxide, hydroxyl radical and metal chelating activity at the maximum concentration of 5mg/ml. The finding of this study reveals that, protein hydrolysates produced has potent antioxidant properties and it could be used as a food supplement in nutraceutical and pharmaceutical industry.

  20. Analysis of protein phosphorylation in nerve terminal reveals extensive changes in active zone proteins upon exocytosis.

    Science.gov (United States)

    Kohansal-Nodehi, Mahdokht; Chua, John Je; Urlaub, Henning; Jahn, Reinhard; Czernik, Dominika

    2016-01-01

    Neurotransmitter release is mediated by the fast, calcium-triggered fusion of synaptic vesicles with the presynaptic plasma membrane, followed by endocytosis and recycling of the membrane of synaptic vesicles. While many of the proteins governing these processes are known, their regulation is only beginning to be understood. Here we have applied quantitative phosphoproteomics to identify changes in phosphorylation status of presynaptic proteins in resting and stimulated nerve terminals isolated from the brains of Wistar rats. Using rigorous quantification, we identified 252 phosphosites that are either up- or downregulated upon triggering calcium-dependent exocytosis. Particularly pronounced were regulated changes of phosphosites within protein constituents of the presynaptic active zone, including bassoon, piccolo, and RIM1. Additionally, we have mapped kinases and phosphatases that are activated upon stimulation. Overall, our study provides a snapshot of phosphorylation changes associated with presynaptic activity and provides a foundation for further functional analysis of key phosphosites involved in presynaptic plasticity. PMID:27115346

  1. Thrombolytic-plus-Anticoagulant Therapy versus Anticoagulant-Alone Therapy in Submassive Pulmonary Thromboembolism (TVASPE Study: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Maryam Taherkhani

    2015-10-01

    Full Text Available Background: The use of thrombolytic agents in the treatment of hemodynamically stable patients with acute submassive pulmonary embolism (PTE remains controversial. We, therefore, conducted this study to compare the effect of thrombolytic plus anticoagulation versus anticoagulation alone on early death and adverse outcome following submassive PTE.Methods: We conducted a study of patients with acute pulmonary embolism and pulmonary hypertension or right ventricular dilatation/dysfunction but without arterial hypotension or shock. The patients were randomly assigned in a single-blind fashion to receive an anticoagulant [Enoxaparin (1 mg/kg twice a day] plus a thrombolytic [Alteplase (100 mg or Streptokinase (1500000 u/2 hours] or an anticoagulant [Enoxaparin (1 mg/kg twice a day] alone. The primary endpoint was in-hospital death or clinical deterioration requiring an escalation of treatment. The secondary endpoints of the study were major bleeding, pulmonary hypertension, right ventricular dilatation at the end of the first week, and exertional dyspnea at the end of the first month.Results: Of 50 patients enrolled, 25 patients were randomly assigned to receive an anticoagulant plus a thrombolytic and the other 25 patients were given an anticoagulant alone. The incidence of the primary endpoints was significantly higher in the anticoagulant-alone group than in the thrombolytic-plus-anticoagulant group (p value = 0.022. At the time of discharge, pulmonary artery pressure was significantly higher in the anticoagulant-alone group than in the thrombolytic- plus-anticoagulant group (p value = 0.018; however, reduction in the right ventricular size or normalization of the right ventricle showed non-significant differences between the two groups. There was no significant difference regarding the New York Heat Association (NYHA functional class between the two groups at the end of the first month (p value = 0.213. No fatal bleeding or cerebral bleeding

  2. Methods to distinguish various types of protein phosphatase activity

    International Nuclear Information System (INIS)

    To distinguish the action of protein Tyr(P) and protein Ser(P)/Thr(P) phosphatases on 32P-labeled phosphoproteins in subcellular fractions different inhibitors and activators are utilized. Comparison of the effects of added compounds provides a convenient, indirect method to characterize dephosphorylation reactions. Protein Tyr(P) phosphatases are specifically inhibited by micromolar Zn2+ or vanadate, and show maximal activity in the presence of EDTA. The other class of cellular phosphatases, specific for protein Ser(P) and Thr(P) residues, are inhibited by fluoride and EDTA. In this class of enzymes two major functional types can be distinguished: those sensitive to inhibition by the heat-stable protein inhibitor-2 and not stimulated by polycations, and those not sensitive to inhibition and stimulated by polycations. Preparation of 32P-labeled Tyr(P) and Ser(P) phosphoproteins also is presented for the direct measurement of phosphatase activities in preparations by the release of acid-soluble [32P]phosphate

  3. Detergent activation of the binding protein in the folate radioassay

    International Nuclear Information System (INIS)

    A minor cow's whey protein associated with β-lactoglobulin is used as binding protein in the competitive radioassay for serum and erythrocyte folate. Seeking to optimize the assay, we tested the performance of binder solutions of increasing purity. The folate binding protein was isolated from cow's whey by means of CM-Sepharose CL-6B cation-exchange chromatography, and further purified on a methotrexate-AH-Sepharose 4B affinity matrix. In contrast to β-lactoglobulin, the purified protein did not bind folate unless the detergents cetyltrimethylammonium (10 mmol/Ll) or Triton X-100 (1 g/L) were present. Such detergent activation was not needed in the presence of serum. There seems to be a striking analogy between these phenomena and the well-known reactivation of certain purified membrane-derived enzymes by surfactants

  4. Potential role of new anticoagulants for prevention and treatment of venous thromboembolism in cancer patients

    Directory of Open Access Journals (Sweden)

    Gómez-Outes A

    2013-05-01

    and treatment of VTE include parenteral compounds for once-daily administration (ie, semuloparin or once-weekly dosing (ie, idraparinux and idrabiotaparinux, as well as orally active compounds (ie, dabigatran, rivaroxaban, apixaban, edoxaban, betrixaban. In the present review, we discuss the pharmacology of the new anticoagulants, the results of clinical trials testing these new compounds in VTE, with special emphasis on studies that included cancer patients, and their potential advantages and drawbacks compared with existing therapies.Keywords: anticoagulants, venous thromboembolism, cancer, dabigatran, apixaban, rivaroxaban

  5. Plasma triacylglycerol and coagulation factor concentrations predict the anticoagulant effect of dietary fish oil in overweight subjects

    DEFF Research Database (Denmark)

    Vanschoonbeek, Kristof; Feijge, Marion A H; Saris, Wim H M; Maat, Moniek de; Heemskerk, Johan W M

    2007-01-01

    Fish oil, containing (n-3) PUFA, is associated with a moderate reduction in cardiovascular disease through a multifactorial mechanism involving a decrease in plasma lipids and anticoagulant activity. Two intervention studies on subjects at risk were performed to determine the relation of these 2 ...

  6. Quantifying Agonist Activity at G Protein-coupled Receptors

    OpenAIRE

    Ehlert, Frederick J.; Suga, Hinako; Griffin, Michael T.

    2011-01-01

    When an agonist activates a population of G protein-coupled receptors (GPCRs), it elicits a signaling pathway that culminates in the response of the cell or tissue. This process can be analyzed at the level of a single receptor, a population of receptors, or a downstream response. Here we describe how to analyze the downstream response to obtain an estimate of the agonist affinity constant for the active state of single receptors.

  7. Recent developments in the use of oral anticoagulants

    DEFF Research Database (Denmark)

    Lassen, Michael R

    2009-01-01

    For many years, vitamin K antagonists, unfractionated heparins, low-molecular-weight heparins and a pentasaccharide were the only anticoagulant drugs available for the prevention of venous thromboembolism after surgery. However, their benefits were associated with disadvantages, such as their...

  8. New direct oral anticoagulants--current therapeutic options and treatment recommendations for bleeding complications.

    Science.gov (United States)

    Miesbach, Wolfgang; Seifried, Erhard

    2012-10-01

    To date, clinical studies show that the incidence of spontaneous bleeding with new direct oral anticoagulants (DOAs) is comparable to that of established anticoagulants. However, unlike vitamin K antagonists, there are currently no clinically available antidotes or approved reversal agents for new DOAs. Restoring normal coagulation is important in many cases, such as emergency surgeries, serious bleedings, or anticoagulant overdosing. Attempts have been made to restore normal coagulation after treatment with new DOAs using compounds such as recombinant activated factor VII (rFVIIa), prothrombin complex concentrate (PCC), or FEIBA (factor eight inhibitor bypassing activity). Limited pre-clinical data and even less clinical evidence are available on the usefulness of these methods in restoring normal coagulation for the emergency management of critical bleeding episodes. Evaluating the utility of DOAs is further complicated by the fact that it is unknown how predictive established test systems are of the bleeding risks. Clinical practice requires further evaluation of the emergency management options for the new DOAs to define the agents and the doses that are most useful. Furthermore, patients receiving long-term treatment with a DOA are likely to undergo elective surgery at some point, and there is lack of evidence regarding perioperative treatment regimens under such conditions. This review summarises potential bleeding management options and available data on the new DOAs. PMID:22782297

  9. Activity-Based Protein Profiling of Rhomboid Proteases in Liposomes

    Czech Academy of Sciences Publication Activity Database

    Wolf, E. V.; Seybold, M.; Hadravová, Romana; Stříšovský, Kvido; Verhelst, S. H. L.

    2015-01-01

    Roč. 16, č. 11 (2015), s. 1616-1621. ISSN 1439-4227 R&D Projects: GA MŠk(CZ) LK11206; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : activity -based protein profiling * chemical probes * inhibitors * intramembrane proteases * liposomes Subject RIV: CE - Biochemistry Impact factor: 3.088, year: 2014

  10. Update of oral surgery management in orally anticoagulated patients

    OpenAIRE

    Dimova, Cena; Evrosimovska, Biljana; Pandilova, Maja; Kovacevska, Ivona; Zabokova-Bilbilova, Efka

    2013-01-01

    Aim of this study is to review the evidence of different therapy approach, to highlight the areas of major concern and to suggest specific oral surgery treatment for patients on oral anticoagulants. The aim of operative treatment is to minimize the risk of hemorrhage while continuing to protect the patient against thromboembolism formation. The ordinary treatment includes the interruption of anticoagulant therapy for oral surgery interventions to prevent hemorrhage. However, this practice may...

  11. Use of tranexamic acid in anticoagulated oral surgery patients

    OpenAIRE

    Dimova, Cena; Papakoca, Kiro; Kovacevska, Ivona; Kamceva, Gordana

    2010-01-01

    INTRODUCTIONS: The oral surgeons are frequently asked to manage patients who are receiving oral anticoagulants. The goal of treatment is to minimize the risk of hemorrhage while continuing to protect the patient against thromboembolism formation. The ordinary treatment includes the interruption of anticoagulant therapy for oral surgery interventions to prevent hemorrhage. AIM:However, this practice may logically increase the risk of a potentially life-threatening thromboembolism. Thus, thi...

  12. Management of oral surgery procedures in orally anticoagulated patients

    OpenAIRE

    Dimova, Cena

    2010-01-01

    The oral and maxillofacial surgeons are frequently asked to manage patients who are receiving oral anticoagulants. The goal of treatment is to minimize the risk of hemorrhage while continuing to protect the patient against thromboembolism formation. The ordinary treatment includes the interruption of anticoagulant therapy for oral surgery interventions to prevent hemorrhage. However, this practice may logically increase the risk of a potentially life-threatening thromboembolism. Thus, this is...

  13. Management of oral surgery procedures in oral anticoagulated patients

    OpenAIRE

    Dimova, Cena

    2010-01-01

    The oral and maxillofacial surgeons are frequently asked to manage patients who are receiving oral anticoagulants. The goal of treatment is to minimize the risk of hemorrhage while continuing to protect the patient against thromboembolism formation. The ordinary treatment includes the interruption of anticoagulant therapy for oral surgery interventions to prevent hemorrhage. However, this practice may logically increase the risk of a potentially life-threatening thromboembolism. Thus, this is...

  14. New perspectives and recommendations for anticoagulant therapy post orthopedic surgery

    OpenAIRE

    Marcelo Kropf; Cleidson Alves Bergami; Felipe Dias Leal; Claudia Oliveira Dias Passos; Zilda de Santana Gonsalves; Isabela Laudares Marques; Isabela Azevedo Mota; Marcele Lima Monte Gonçalves

    2011-01-01

    Anticoagulant therapy is essential for the prevention of risks associated with the formation of thrombus in patients after surgery, especially in orthopedics. Recently, new oral anticoagulants were introduced in the therapeutic arsenal. This fact is important, because the current drug of choice in clinical practice is enoxaparin, a low molecular weight heparin. As all injecting drugs, enoxaparin may reduce patients' adherence to treatment by dissatisfaction with and resistance to the administ...

  15. Use of antifibrinolytic mouthwash solution in anticoagulated oral surgery patients

    OpenAIRE

    Dimova, Cena; Evrosimovska, Biljana; Papakoca, Kiro; Georgiev, Zlatko; Angelovska, Bistra; Ristoska, Sonja

    2012-01-01

    Introduction:The ordinary treatment of anticoagulated patients includes the interruption of anticoagulant therapy for oral surgery interventions to prevent hemorrhage. However, this practice may logically increase the risk of a potentially life-threatening thromboembolism, so this issue is still controversial. The aim of the study was to evaluate the antifibrinolitic mouthwash solution (tranexamic acid) as a local haemostatic modality after oral surgery interventions. Methods:To realize the a...

  16. The Comprehensive Management of Anticoagulation: Ochsner Coumadin Clinic

    OpenAIRE

    Barrios, Annette C.; Ventura, Hector O.; Milani, Richard V.

    2002-01-01

    Clinical privileging of pharmacists and the effective use of support staff and information technology have helped create an efficient pharmacist-operated anticoagulation clinic at Ochsner Clinic Foundation that will support future growth efforts for improved patient care. Developed by Ochsner's Department of Cardiology, the pharmacist-operated anticoagulation clinic cares for 2000 patients with a clinical pharmacist, staff pharmacist, registered nurse, and medical assistants. Patients are man...

  17. Anticoagulant Rodenticide Intoxication in Animals – A Review

    OpenAIRE

    VALCHEV, Ivan; Binev, Rumen; YORDANOVA, Veska; Nikolov, Yordan

    2008-01-01

    The newest measures for the control of harmful rodent populations are from the anticoagulant rodenticide group, which are divided into 2 subgroups: first and second generations, and indandione derivatives. Non-target organisms are potentially at risk of direct consumption of baits (primary hazard) and of eating poisoned rodents (secondary hazard). Anticoagulant rodenticides inhibit the enzyme vitamin K-dependent carboxylase and thus impair the reactivation of vitamin K1, indirectly affecting ...

  18. Mechanical Prosthetic Valves and Pregnancy: A therapeutic dilemma of anticoagulation

    OpenAIRE

    Prashanth Panduranga; Mohammed El-Deeb; Chitra Jha

    2014-01-01

    Choosing the best anticoagulant therapy for a pregnant patient with a mechanical prosthetic valve is controversial and the published international guidelines contain no clear-cut consensus on the best approach. This is due to the fact that there is presently no anticoagulant which can reliably decrease thromboembolic events while avoiding damage to the fetus. Current treatments include either continuing oral warfarin or substituting warfarin for subcutaneous unfractionated heparin or low-mole...

  19. Novel Anticoagulants in Atrial Fibrillation: Monitoring, Reversal and Perioperative Management

    OpenAIRE

    Fadi Shamoun; Hiba Obeid; Harish Ramakrishna

    2015-01-01

    Atrial fibrillation continues to be a significant source of morbidity and mortality worldwide. Effective anticoagulation remains the cornerstone of outpatient and inpatient treatment. The use of the new generation of anticoagulants (NOACs) continues to grow. Recently published data indicate their cost-effectiveness and overall safety in stroke prevention; compared to vitamin K antagonists, they can be prescribed in fixed doses for long-term therapy without the need for coagulation monitoring....

  20. Reassessing the Potential Activities of Plant CGI-58 Protein.

    Science.gov (United States)

    Khatib, Abdallah; Arhab, Yani; Bentebibel, Assia; Abousalham, Abdelkarim; Noiriel, Alexandre

    2016-01-01

    Comparative Gene Identification-58 (CGI-58) is a widespread protein found in animals and plants. This protein has been shown to participate in lipolysis in mice and humans by activating Adipose triglyceride lipase (ATGL), the initial enzyme responsible for the triacylglycerol (TAG) catabolism cascade. Human mutation of CGI-58 is the cause of Chanarin-Dorfman syndrome, an orphan disease characterized by a systemic accumulation of TAG which engenders tissue disorders. The CGI-58 protein has also been shown to participate in neutral lipid metabolism in plants and, in this case, a mutation again provokes TAG accumulation. Although its roles as an ATGL coactivator and in lipid metabolism are quite clear, the catalytic activity of CGI-58 is still in question. The acyltransferase activities of CGI-58 have been speculated about, reported or even dismissed and experimental evidence that CGI-58 expressed in E. coli possesses an unambiguous catalytic activity is still lacking. To address this problem, we developed a new set of plasmids and site-directed mutants to elucidate the in vivo effects of CGI-58 expression on lipid metabolism in E. coli. By analyzing the lipid composition in selected E. coli strains expressing CGI-58 proteins, and by reinvestigating enzymatic tests with adequate controls, we show here that recombinant plant CGI-58 has none of the proposed activities previously described. Recombinant plant and mouse CGI-58 both lack acyltransferase activity towards either lysophosphatidylglycerol or lysophosphatidic acid to form phosphatidylglycerol or phosphatidic acid and recombinant plant CGI-58 does not catalyze TAG or phospholipid hydrolysis. However, expression of recombinant plant CGI-58, but not mouse CGI-58, led to a decrease in phosphatidylglycerol in all strains of E. coli tested, and a mutation of the putative catalytic residues restored a wild-type phenotype. The potential activities of plant CGI-58 are subsequently discussed. PMID:26745266

  1. Reassessing the Potential Activities of Plant CGI-58 Protein.

    Directory of Open Access Journals (Sweden)

    Abdallah Khatib

    Full Text Available Comparative Gene Identification-58 (CGI-58 is a widespread protein found in animals and plants. This protein has been shown to participate in lipolysis in mice and humans by activating Adipose triglyceride lipase (ATGL, the initial enzyme responsible for the triacylglycerol (TAG catabolism cascade. Human mutation of CGI-58 is the cause of Chanarin-Dorfman syndrome, an orphan disease characterized by a systemic accumulation of TAG which engenders tissue disorders. The CGI-58 protein has also been shown to participate in neutral lipid metabolism in plants and, in this case, a mutation again provokes TAG accumulation. Although its roles as an ATGL coactivator and in lipid metabolism are quite clear, the catalytic activity of CGI-58 is still in question. The acyltransferase activities of CGI-58 have been speculated about, reported or even dismissed and experimental evidence that CGI-58 expressed in E. coli possesses an unambiguous catalytic activity is still lacking. To address this problem, we developed a new set of plasmids and site-directed mutants to elucidate the in vivo effects of CGI-58 expression on lipid metabolism in E. coli. By analyzing the lipid composition in selected E. coli strains expressing CGI-58 proteins, and by reinvestigating enzymatic tests with adequate controls, we show here that recombinant plant CGI-58 has none of the proposed activities previously described. Recombinant plant and mouse CGI-58 both lack acyltransferase activity towards either lysophosphatidylglycerol or lysophosphatidic acid to form phosphatidylglycerol or phosphatidic acid and recombinant plant CGI-58 does not catalyze TAG or phospholipid hydrolysis. However, expression of recombinant plant CGI-58, but not mouse CGI-58, led to a decrease in phosphatidylglycerol in all strains of E. coli tested, and a mutation of the putative catalytic residues restored a wild-type phenotype. The potential activities of plant CGI-58 are subsequently discussed.

  2. In vitro antithrombotic activities of peanut protein hydrolysates.

    Science.gov (United States)

    Zhang, Shao Bing

    2016-07-01

    The antithrombotic activities of peanut protein hydrolysates were investigated using a microplates assay. When peanut proteins were hydrolyzed to a limited extent by various enzymes, their thrombin inhibitory abilities were significantly enhanced. However, the resultant hydrolysates showed significantly different activities even at the same degrees of hydrolysis. The hydrolysates generated by Alcalase 2.4L displayed the best antithrombotic activities and the hydrolysis process was further optimized by response surface methodology. The antithrombotic activities were increased to 86% based on a protein concentration of 50mg/ml under the optimal conditions: pH 8.5, enzyme concentration of 5000IU/g of peanut proteins, and 2h hydrolysis time at 50°C. The Alcalase 2.4L crude hydrolysates were then fractionated successively by preparative and semi-preparative reverse-phase high-performance liquid chromatography (RP-HPLC). The peptide fraction collected inhibited thrombin-catalyzed coagulation of fibrinogen completely at a concentration of 0.4mg/ml, with an antithrombotic activity close to that of heparin at quite a low concentration (0.2mg/ml). This peptide fraction was further analyzed by online reverse-phase ultra-performance liquid chromatography (RP-UPLC) coupled to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and three new peptides were identified as Ser-Trp-Ala-Gln-Leu, Gly-Asn-His-Glu-Ala-Gly-Glu and Cys-Phe-Asn-Glu-Tyr-Glu, respectively. This research provided an effective way to produce antithrombotic peptides from peanut proteins, and also helped to elucidate the structure-function relationships of peanut peptides. PMID:26920259

  3. Turnover of whole body proteins and myofibrillar proteins in middle-aged active men

    International Nuclear Information System (INIS)

    Endurance-trained older men have a higher proportion of lean tissue and greater muscle cell oxidative capacity, reversing age-related trends and suggesting major changes in protein metabolism. In this study, protein turnover was determined in 6 middle-aged (52+/-1 yr) men who were well trained (VO2 max 55.2+/-5.0 ml O2/kg.min) and lean (body fat 18.9+/-2.8%, muscle mass 36.6+/-0.6%). The maintained habitual exercise while consuming 0.6, 0.9 or 1.2 g protein/kg.day for 10-day periods. N flux was measured from 15N in urea after oral 15N-glycine administration. Myofibrillar protein breakdown was estimated from urinary 3-methyl-histidine. Dietary protein had no effect on turnover rates, even when N balance was negative. Whole body protein synthesis was 3.60+/-0.12 g/kg.day and breakdown was 3.40+/-0.14 g/kg.day for all N intakes. Whole body protein flux, synthesis and breakdown were similar to values reported for sedentary young (SY) or sedentary old (SO) men on comparable diets. 3-me-his (3.67+/-0.14 μmol/kg.day) was similar to values reported for SY but higher (p<0.01) than for SO. Myofibrillar protein breakdown per unit muscle mass (185+/-7 μmol 3-me-his/g creatinine) was higher (p<0.01) than for SY or SO. In active middle-aged men, myofibrillar proteins may account for a greater proportion of whole body protein turnover, despite an age-related reduction in muscle mass

  4. Adherence to a new oral anticoagulant treatment prescription: dabigatran etexilate

    Directory of Open Access Journals (Sweden)

    L Bellamy

    2009-07-01

    Full Text Available L Bellamy1, N Rosencher1, BI Eriksson21Anaesthesiology Department, Hôpital Cochin (AP-HP, René Descartes University, Paris 75014 France; 2Orthopaedic Department, University Hospital Sahlgrenska/Ostra, Gothenburg, SwedenAbstract: The recent development of new oral anticoagulants, of which dabigatran etexilate is currently at the most advanced stage of development, is the greatest advance in the provision of convenient anticoagulation therapy for many years. A new oral anticoagulation treatment, dabigatran etexilate, is already on the market in Europe. The main interest probably will be to improve the prescription and the adherence to an effective thromboprophylaxis in medical conditions such as atrial fibrillation without bleeding side effects, without the need for monitoring coagulation, and without drug and food interactions such as vitamin K anticoagulant (VKA treatment. Dabigatran is particularly interesting for extended thromboprophylaxis after major orthopedic surgery in order to avoid daily injection for a month. However, oral long-term treatments such as VKA are not systematically associated with a higher compliance level than injected treatments such as low-molecular-weight heparins. Indeed, adherence to an oral treatment, instead of the usual daily injection in major orthopedic surgery, is complex, and based not only on the frequency of dosing but also on patient motivation, understanding, and socio-economic status. New oral anticoagulants may be useful in this way but education and detection of risk factors of nonadherence to treatment are still essential.Keywords: oral anticoagulant, adherence, compliance, education, dabigatran

  5. New anticoagulants for the prevention of venous thromboembolism

    Science.gov (United States)

    Becattini, Cecilia; Lignani, Alessandra; Agnelli, Giancarlo

    2010-01-01

    Anticoagulant drugs have an essential role in the prevention and treatment of thromboembolic diseases. Currently available anticoagulants substantially reduce the incidence of thromboembolic events in a number of clinical conditions. However, these agents have limitations that strengthen the case for the development of new anticoagulants. An ideal anticoagulant should be at least as effective as those currently in use, as well as safe, simple to use, and widely applicable. The majority of new anticoagulants currently under investigation are small molecules with a selective and direct anti-Xa or antithrombin action, allowing oral administration in fixed doses. These new agents are in different phases of clinical development. The anti-Xa agent rivaroxaban and the antithrombin agent dabigatran are already available for the prophylaxis of venous thromboembolism in some countries. Apixaban is in an advanced phase of clinical development and several anti-Xa agents are currently approaching phase III clinical trials. Promising results in terms of efficacy and safety profiles have been obtained with these agents in different clinical conditions. Differences in pharmacokinetics and pharmacodynamics could offer the potential for individualized anticoagulant therapies in the near future. PMID:20531960

  6. [Duration of anticoagulant therapy in venous thromboembolic complications].

    Science.gov (United States)

    Kuznetsov, M R; Leontyev, S G; Neskhodimov, L A; Tolstikhin, V Yu; Khotinskiy, A A

    2016-01-01

    Adequate anticoagulant therapy is a general approach to treatment of deep vein thrombosis. However, the duration of anticoagulant therapy is not strictly specified in everyday clinical practice. The present article deals with various approaches to selecting the duration of therapy with anticoagulants based on the findings of studies, national and foreign clinical guidelines. The minimal duration of therapy for deep vein thrombosis and pulmonary thromboembolism amounts to 3 months in accordance with the national and American recommendations. For some cohorts of patients, continuation of therapy above 3 months is considered: patients with idiopathic thrombosis (the recommended duration of therapy of not less than 6 months), patients having persisting risk factor for relapse of thrombosis on termination of the main therapeutic course, oncological patients (6 month therapy followed by assessing the risk and benefit of continuing therapy with anticoagulants). Prolonged therapy of venous thromboembolism using unfractionated heparin or low-molecular-weight heparin followed by changing over to vitamin K antagonists is associated with decreased risk for thrombosis relapse approximately by 90%, however increasing the risk of haemorrhage. Currently, as an alternative, it is possible to consider administration of novel oral anticoagulants (rivaroxaban, dabigatran, apixaban) which beside high efficacy are associated with less risk of bleeding. The route of administration, no necessity to control the INR, and the minimal number of drug and food interactions make administration of new oral anticoagulants an attractive alternative to therapy with heparins and vitamin K antagonists. PMID:27100556

  7. Establishing an outpatient anticoagulation clinic in a community hospital.

    Science.gov (United States)

    Norton, J L; Gibson, D L

    1996-05-15

    The establishment of a pharmacist-managed out-patient anticoagulation clinic in a private community hospital is described. Discussions by pharmacy with office-based physicians at a 187-bed, private, nonprofit community medical center indicated that the traditional system of anticoagulation management was not ideal for the physicians or their patients. Development of a pharmacist-managed anticoagulation clinic began in fall 1993; operations began in spring 1994. Planning included analyzing existing practices, reviewing the relevant literature, obtaining physician input, visiting an established anticoagulation clinic, formulating a business plan, and developing clinical protocols. Collaborative relationships were established with the hospital laboratory, business office, and risk management, information services, and medical records departments. Two pharmacists were trained to work in the clinic and provide coverage 24 hours a day. Services include patient assessment, monitoring of anticoagulation, warfarin dosage adjustment, medication management, patient education, follow-up care, and providing feedback to referring and attending physicians. The clinic has met with physician and patient satisfaction, has reduced the number of admissions to treat warfarin-related bleeding, and has been able to cover its direct costs. A pharmacist-managed anti-coagulation clinic was successfully established in a private community hospital. PMID:8734675

  8. Auxin efflux by PIN-FORMED proteins is activated by two different protein kinases, D6 PROTEIN KINASE and PINOID

    KAUST Repository

    Zourelidou, Melina

    2014-06-19

    The development and morphology of vascular plants is critically determined by synthesis and proper distribution of the phytohormone auxin. The directed cell-to-cell distribution of auxin is achieved through a system of auxin influx and efflux transporters. PIN-FORMED (PIN) proteins are proposed auxin efflux transporters, and auxin fluxes can seemingly be predicted based on the-in many cells-asymmetric plasma membrane distribution of PINs. Here, we show in a heterologous Xenopus oocyte system as well as in Arabidopsis thaliana inflorescence stems that PIN-mediated auxin transport is directly activated by D6 PROTEIN KINASE (D6PK) and PINOID (PID)/WAG kinases of the Arabidopsis AGCVIII kinase family. At the same time, we reveal that D6PKs and PID have differential phosphosite preferences. Our study suggests that PIN activation by protein kinases is a crucial component of auxin transport control that must be taken into account to understand auxin distribution within the plant.

  9. Haptoglobin inhibits phospholipid transfer protein activity in hyperlipidemic human plasma

    Directory of Open Access Journals (Sweden)

    Leon Carlos G

    2009-07-01

    Full Text Available Abstract Background Haptoglobin is a plasma protein that scavenges haemoglobin during haemolysis. Phospholipid Transfer Protein (PLTP transfers lipids from Low Density Lipoproteins (LDL to High Density Lipoproteins (HDL. PLTP is involved in the pathogenesis of atherosclerosis which causes coronary artery disease, the leading cause of death in North America. It has been shown that Apolipoprotein-A1 (Apo-A1 binds and regulates PLTP activity. Haptoglobin can also bind to Apo-A1, affecting the ability of Apo-A1 to induce enzymatic activities. Thus we hypothesize that haptoglobin inhibits PLTP activity. This work tested the effect of Haptoglobin and Apo-A1 addition on PLTP activity in human plasma samples. The results will contribute to our understanding of the role of haptoglobin on modulating reverse cholesterol transport. Results We analyzed the PLTP activity and Apo-A1 and Haptoglobin content in six hyperlipidemic and six normolipidemic plasmas. We found that Apo-A1 levels are proportional to PLTP activity in hyperlipidemic (R2 = 0.66, p 2 = 0.57, p > 0.05. When the PLTP activity was graphed versus the Hp/Apo-A1 ratio in hyperlipidemic plasma there was a significant correlation (R2 = 0.69, p Conclusion These findings suggest an inhibitory effect of Haptoglobin over PLTP activity in hyperlipidemic plasma that may contribute to the regulation of reverse cholesterol transport.

  10. Design of a Split Intein with Exceptional Protein Splicing Activity.

    Science.gov (United States)

    Stevens, Adam J; Brown, Zachary Z; Shah, Neel H; Sekar, Giridhar; Cowburn, David; Muir, Tom W

    2016-02-24

    Protein trans-splicing (PTS) by split inteins has found widespread use in chemical biology and biotechnology. Herein, we describe the use of a consensus design approach to engineer a split intein with enhanced stability and activity that make it more robust than any known PTS system. Using batch mutagenesis, we first conduct a detailed analysis of the difference in splicing rates between the Npu (fast) and Ssp (slow) split inteins of the DnaE family and find that most impactful residues lie on the second shell of the protein, directly adjacent to the active site. These residues are then used to generate an alignment of 73 naturally occurring DnaE inteins that are predicted to be fast. The consensus sequence from this alignment (Cfa) demonstrates both rapid protein splicing and unprecedented thermal and chaotropic stability. Moreover, when fused to various proteins including antibody heavy chains, the N-terminal fragment of Cfa exhibits increased expression levels relative to other N-intein fusions. The durability and efficiency of Cfa should improve current intein based technologies and may provide a platform for the development of new protein chemistry techniques. PMID:26854538

  11. Protein kinase domain of twitchin has protein kinase activity and an autoinhibitory region.

    Science.gov (United States)

    Lei, J; Tang, X; Chambers, T C; Pohl, J; Benian, G M

    1994-08-19

    Twitchin is a 753-kDa polypeptide located in the muscle A-bands of the nematode, Caenorhabditis elegans. It consists of multiple copies of both fibronectin III and immunoglobulin C2 domains and, near the C terminus, a protein kinase domain with greatest homology to the catalytic domains of myosin light chain kinases. We have expressed and purified from Escherichia coli twitchin's protein kinase catalytic core and flanking sequences that do not include fibronectin III and immunoglobulin C2 domains. The protein was shown to phosphorylate a model substrate and to undergo autophosphorylation. The autophosphorylation occurs at a slow rate, attaining a maximum at 3 h with a stoichiometry of about 1.0 mol of phosphate/mol of protein, probably through an intramolecular mechanism. Sequence analysis of proteolytically derived phosphopeptides revealed that autophosphorylation occurred N-terminal to the catalytic core, predominantly at Thr-5910, with possible minor sites at Ser5912 and/or Ser-5913. This portion of twitchin (residues 5890-6268) was also phosphorylated in vitro by protein kinase C in the absence of calcium and phosphotidylserine, but not by cAMP-dependent protein kinase. By comparing the activities of three twitchin segments, the enzyme appears to be inhibited by the 60-amino acid residues lying just C-terminal to the kinase catalytic core. Thus, like a number of other protein kinases including myosin light chain kinases, the twitchin kinase appears to be autoregulated. PMID:8063727

  12. NRIP, a novel calmodulin binding protein, activates calcineurin to dephosphorylate human papillomavirus E2 protein.

    Science.gov (United States)

    Chang, Szu-Wei; Tsao, Yeou-Ping; Lin, Chia-Yi; Chen, Show-Li

    2011-07-01

    Previously, we found a gene named nuclear receptor interaction protein (NRIP) (or DCAF6 or IQWD1). We demonstrate that NRIP is a novel binding protein for human papillomavirus 16 (HPV-16) E2 protein. HPV-16 E2 and NRIP can directly associate into a complex in vivo and in vitro, and the N-terminal domain of NRIP interacts with the transactivation domain of HPV-16 E2. Only full-length NRIP can stabilize E2 protein and induce HPV gene expression, and NRIP silenced by two designed small interfering RNAs (siRNAs) decreases E2 protein levels and E2-driven gene expression. We found that NRIP can directly bind with calmodulin in the presence of calcium through its IQ domain, resulting in decreased E2 ubiquitination and increased E2 protein stability. Complex formation between NRIP and calcium/calmodulin activates the phosphatase calcineurin to dephosphorylate E2 and increase E2 protein stability. We present evidences for E2 phosphorylation in vivo and show that NRIP acts as a scaffold to recruit E2 and calcium/calmodulin to prevent polyubiquitination and degradation of E2, enhancing E2 stability and E2-driven gene expression. PMID:21543494

  13. Activation of autophagy by unfolded proteins during endoplasmic reticulum stress.

    Science.gov (United States)

    Yang, Xiaochen; Srivastava, Renu; Howell, Stephen H; Bassham, Diane C

    2016-01-01

    Endoplasmic reticulum stress is defined as the accumulation of unfolded proteins in the endoplasmic reticulum, and is caused by conditions such as heat or agents that cause endoplasmic reticulum stress, including tunicamycin and dithiothreitol. Autophagy, a major pathway for degradation of macromolecules in the vacuole, is activated by these stress agents in a manner dependent on inositol-requiring enzyme 1b (IRE1b), and delivers endoplasmic reticulum fragments to the vacuole for degradation. In this study, we examined the mechanism for activation of autophagy during endoplasmic reticulum stress in Arabidopsis thaliana. The chemical chaperones sodium 4-phenylbutyrate and tauroursodeoxycholic acid were found to reduce tunicamycin- or dithiothreitol-induced autophagy, but not autophagy caused by unrelated stresses. Similarly, over-expression of BINDING IMMUNOGLOBULIN PROTEIN (BIP), encoding a heat shock protein 70 (HSP70) molecular chaperone, reduced autophagy. Autophagy activated by heat stress was also found to be partially dependent on IRE1b and to be inhibited by sodium 4-phenylbutyrate, suggesting that heat-induced autophagy is due to accumulation of unfolded proteins in the endoplasmic reticulum. Expression in Arabidopsis of the misfolded protein mimics zeolin or a mutated form of carboxypeptidase Y (CPY*) also induced autophagy in an IRE1b-dependent manner. Moreover, zeolin and CPY* partially co-localized with the autophagic body marker GFP-ATG8e, indicating delivery to the vacuole by autophagy. We conclude that accumulation of unfolded proteins in the endoplasmic reticulum is a trigger for autophagy under conditions that cause endoplasmic reticulum stress. PMID:26616142

  14. Heat Shock Protein 90 Indirectly Regulates ERK Activity by Affecting Raf Protein Metabolism

    Institute of Scientific and Technical Information of China (English)

    Fei DOU; Liu-Di YUAN; Jing-Jing ZHU

    2005-01-01

    Extracellular signal-regulated protein kinase (ERK) has been implicated in the pathogenesis of several nerve system diseases. As more and more kinases have been discovered to be the client proteins of the molecular chaperone Hsp90, the use of Hsp90 inhibitors to reduce abnormal kinase activity is a new treatment strategy for nerve system diseases. This study investigated the regulation of the ERK pathway by Hsp90. We showed that Hsp90 inhibitors reduce ERK phosphorylation without affecting the total ERK protein level. Further investigation showed that Raf, the upstream kinase in the Ras-Raf-MEK-ERK pathway,forms a complex with Hsp90 and Hsp70. Treating cells with Hsp90 inhibitors facilitates Raf degradation,thereby down-regulating the activity of ERK.

  15. Current activities of the Yersinia effector protein YopM.

    Science.gov (United States)

    Höfling, Sabrina; Grabowski, Benjamin; Norkowski, Stefanie; Schmidt, M Alexander; Rüter, Christian

    2015-05-01

    Yersinia outer protein M (YopM) belongs to the group of Yop effector proteins, which are highly conserved among pathogenic Yersinia species. During infection, the effectors are delivered into the host cell cytoplasm via the type 3 secretion system to subvert the host immune response and support the survival of Yersinia. In contrast to the other Yop effectors, YopM does not possess a known enzymatic activity and its molecular mechanism(s) of action remain(s) poorly understood. However, YopM was shown to promote colonization and dissemination of Yersinia, thus being crucial for the pathogen's virulence in vivo. Moreover, YopM interacts with several host cell proteins and might utilize them to execute its anti-inflammatory activities. The results obtained so far indicate that YopM is a multifunctional protein that counteracts the host immune defense by multiple activities, which are at least partially independent of each other. Finally, its functions seem to be also influenced by differences between the specific YopM isoforms expressed by Yersinia subspecies. In this review, we focus on the global as well as more specific contribution of YopM to virulence of Yersinia during infection and point out the various extra- and intracellular molecular functions of YopM. In addition, the novel cell-penetrating ability of recombinant YopM and its potential applications as a self-delivering immunomodulatory therapeutic will be discussed. PMID:25865799

  16. Pharmacological activities in thermal proteins: relationships in molecular evolution

    Science.gov (United States)

    Fox, S. W.; Hefti, F.; Hartikka, J.; Junard, E.; Przybylski, A. T.; Vaughan, G.

    1987-01-01

    The model of protobiological events that has been presented in these pages has increasing relevance to pharmacological research. The thermal proteins that function as key substances in the proteinoid theory have recently been found to prolong the survival of rat forebrain neurons in culture and to stimulate the growth of neurites. A search for such activity in thermal proteins added to cultures of modern neurons was suggested by the fact that some of the microspheres assembled from proteinoids rich in hydrophobic amino acids themselves generate fibrous outgrowths.

  17. Thrombolytic-plus-Anticoagulant Therapy versus Anticoagulant-Alone Therapy in Submassive Pulmonary Thromboembolism (TVASPE Study): A Randomized Clinical Trial

    OpenAIRE

    Maryam Taherkhani; Adineh Taherkhani; SeyedReza Hashemi; Taraneh Faghihi-Langroodi; Roxana Sadeghi; Mohammadreza Beyranvand

    2014-01-01

    Background: The use of thrombolytic agents in the treatment of hemodynamically stable patients with acute submassive pulmonary embolism (PTE) remains controversial. We, therefore, conducted this study to compare the effect of thrombolytic plus anticoagulation versus anticoagulation alone on early death and adverse outcome following submassive PTE.Methods: We conducted a study of patients with acute pulmonary embolism and pulmonary hypertension or right ventricular dilatation/dysfunction but w...

  18. Anticoagulation reversal in the era of the non-vitamin K oral anticoagulants

    DEFF Research Database (Denmark)

    Enriquez, Andres; Lip, Gregory Y H; Baranchuk, Adrian

    2016-01-01

    In recent years, non-vitamin K oral anticoagulants (NOACs) have emerged as an alternative to warfarin for the prevention and treatment of thrombo-embolic disease. Large randomized trials have demonstrated that these agents, which act by directly targeting thrombin (dabigatran) and factor Xa....... New specific antidotes (e.g. idarucizumab, andexanet alfa, and ciraparantag) show promising data, and may soon become available for clinical use. In this article, we review the pharmacology of these agents, the incidence and outcomes of haemorrhagic complications, the available strategies for...

  19. L-Alanylglutamine inhibits signaling proteins that activate protein degradation, but does not affect proteins that activate protein synthesis after an acute resistance exercise.

    Science.gov (United States)

    Wang, Wanyi; Choi, Ran Hee; Solares, Geoffrey J; Tseng, Hung-Min; Ding, Zhenping; Kim, Kyoungrae; Ivy, John L

    2015-07-01

    Sustamine™ (SUS) is a dipeptide composed of alanine and glutamine (AlaGln). Glutamine has been suggested to increase muscle protein accretion; however, the underlying molecular mechanisms of glutamine on muscle protein metabolism following resistance exercise have not been fully addressed. In the present study, 2-month-old rats climbed a ladder 10 times with a weight equal to 75 % of their body mass attached at the tail. Rats were then orally administered one of four solutions: placebo (PLA-glycine = 0.52 g/kg), whey protein (WP = 0.4 g/kg), low dose of SUS (LSUS = 0.1 g/kg), or high dose of SUS (HSUS = 0.5 g/kg). An additional group of sedentary (SED) rats was intubated with glycine (0.52 g/kg) at the same time as the ladder-climbing rats. Blood samples were collected immediately after exercise and at either 20 or 40 min after recovery. The flexor hallucis longus (FHL), a muscle used for climbing, was excised at 20 or 40 min post exercise and analyzed for proteins regulating protein synthesis and degradation. All supplements elevated the phosphorylation of FOXO3A above SED at 20 min post exercise, but only the SUS supplements significantly reduced the phosphorylation of AMPK and NF-kB p65. SUS supplements had no effect on mTOR signaling, but WP supplementation yielded a greater phosphorylation of mTOR, p70S6k, and rpS6 compared with PLA at 20 min post exercise. However, by 40 min post exercise, phosphorylation of mTOR and rpS6 in PLA had risen to levels not different than WP. These results suggest that SUS blocks the activation of intracellular signals for MPB, whereas WP accelerates mRNA translation. PMID:25837301

  20. Methods of measuring Protein Disulfide Isomerase activity: a critical overview

    Directory of Open Access Journals (Sweden)

    DeniseCFernandes

    2014-09-01

    Full Text Available Protein disulfide isomerase is an essential redox chaperone from the endoplasmic reticulum (ER and is responsible for correct disulfide bond formation in nascent proteins. PDI is also found in other cellular locations in the cell, particularly the cell surface. Overall, PDI contributes to ER and global cell redox homeostasis and signaling. The knowledge about PDI structure and function progressed substantially based on in vitro studies using recombinant PDI and chimeric proteins. In these experimental scenarios, PDI reductase and chaperone activities are readily approachable. In contrast, assays to measure PDI isomerase activity, the hallmark of PDI family, are more complex. Assessment of PDI roles in cells and tissues mainly relies on gain- or loss-of-function studies. However, there is limited information regarding correlation of experimental readouts with the distinct types of PDI activities. In this mini-review, we evaluate the main methods described for measuring the different kinds of PDI activity: thiol reductase, thiol oxidase, thiol isomerase and chaperone. We emphasize the need to use appropriate controls and the role of critical interferents (e.g., detergent, presence of reducing agents. We also discuss the translation of results from in vitro studies with purified recombinant PDI to cellular and tissue samples, with critical comments on the interpretation of results.

  1. Pros and cons of new oral anticoagulants in the treatment of venous thromboembolism in patients with cancer.

    Science.gov (United States)

    Verso, Melina; Agnelli, Giancarlo; Prandoni, Paolo

    2015-09-01

    Patients with cancer account for 20 % of cases of venous thromboembolism (VTE). Cancer patients are at increased risk for VTE during the entire course of their disease, also in absence of traditional VTE risk factors. Furthermore, patients with VTE and cancer have an estimated risk of bleeding of 15-20 % per year while on anticoagulant treatment. For these reasons, treatment of acute VTE in patients with cancer remains a clinical challenge. In clinical studies, which included about 27,000 patients, new oral anticoagulants (NOACs) have been shown to be as effective and safe as conventional anticoagulation (heparin given with and followed by vitamin K antagonists) for the treatment of VTE. In these studies, 1227 patients with active cancer were enrolled. Preliminary results of subgroup analyses and meta-analyses of randomized clinical trials suggest that NOACs could represent an alternative to conventional anticoagulation in patients with active cancer. Further "ad hoc" studies evaluating the clinical benefit of treatment with NOACs in patients with VTE and cancer are needed. PMID:25840679

  2. Modulation of the protein kinase activity of mTOR.

    Science.gov (United States)

    Lawrence, J C; Lin, T A; McMahon, L P; Choi, K M

    2004-01-01

    mTOR is a founding member of a family of protein kinases having catalytic domains homologous to those in phosphatidylinositol 3-OH kinase. mTOR participates in the control by insulin of the phosphorylation of lipin, which is required for adipocyte differentiation, and the two translational regulators, p70S6K and PHAS-I. The phosphorylation of mTOR, itself, is stimulated by insulin in Ser2448, a site that is also phosphorylated by protein kinase B (PKB) in vitro and in response to activation of PKB activity in vivo. Ser2448 is located in a short stretch of amino acids not found in the two TOR proteins in yeast. A mutant mTOR lacking this stretch exhibited increased activity, and binding of the antibody, mTAb-1, to this region markedly increased mTOR activity. In contrast, rapamycin-FKBP12 inhibited mTOR activity towards both PHAS-I and p70S6K, although this complex inhibited the phosphorylation of some sites more than that of others. Mutating Ser2035 to Ile in the FKBP12-rapamycin binding domain rendered mTOR resistant to inhibition by rapamycin. Unexpectedly, this mutation markedly decreased the ability of mTOR to phosphorylate certain sites in both PHAS-I and p70S6K. The results support the hypotheses that rapamycin disrupts substrate recognition instead of directly inhibiting phosphotransferase activity and that mTOR activity in cells is controlled by the phosphorylation of an inhibitory regulatory domain containing the mTAb-1 epitope. PMID:14560959

  3. Antioxidant, Antibacterial, and Cytoprotective Activity of Agathi Leaf Protein

    Directory of Open Access Journals (Sweden)

    A. S. Zarena

    2014-01-01

    Full Text Available In the present study a protein termed agathi leaf protein (ALP from Sesbania grandiflora Linn. (agathi leaves was isolated after successive precipitation with 65% ammonium sulphate followed by purification on Sephadex G 75. The column chromatography of the crude protein resulted in four peaks of which Peak I (P I showed maximum inhibition activity against hydroxyl radical. SDS-PAGE analysis of P I indicated that the molecular weight of the protein is ≈29 kDa. The purity of the protein was 98.4% as determined by RP-HPLC and showed a single peak with a retention time of 19.9 min. ALP was able to reduce oxidative damage by scavenging lipid peroxidation against erythrocyte ghost (85.50 ± 6.25%, linolenic acid (87.67 ± 3.14% at 4.33 μM, ABTS anion (88 ± 3.22%, and DNA damage (83 ± 4.20% at 3.44 μM in a dose-dependent manner. The purified protein offered significant protection to lymphocyte (72% at 30 min induced damage by t-BOOH. In addition, ALP showed strong antibacterial activity against Pseudomonas aeruginosa (20 ± 3.64 mm and Staphylococcus aureus (19 ± 1.53 mm at 200 μg/mL. The safety assessment showed that ALP does not induce cytotoxicity towards human lymphocyte at the tested concentration of 0.8 mg/mL.

  4. Anti-thrombin III, Protein C, and Protein S deficiency in acute coronary syndrome

    Directory of Open Access Journals (Sweden)

    Dasnan Ismail

    2002-06-01

    Full Text Available The final most common pathway for the majority of coronary artery disease is occlusion of a coronary vessel. Under normal conditions, antithrombin III (AT III, protein C, and protein S as an active protein C cofactor, are natural anticoagulants (hemostatic control that balances procoagulant activity (thrombin antithrombin complex balance to prevent thrombosis. If the condition becomes unbalanced, natural anticoagulants and the procoagulants can lead to thrombosis. Thirty subjects with acute coronary syndrome (ACS were studied for the incidence of antithrombin III (AT III, protein C, and protein S deficiencies, and the result were compare to the control group. Among patients with ACS, the frequency of distribution of AT-III with activity < 75% were 23,3% (7 of 30, and only 6,7% ( 2 of 30 in control subject. No one of the 30 control subject have protein C activity deficient, in ACS with activity < 70% were 13,3% (4 of 30. Fifteen out of the 30 (50% control subjects had protein S activity deficiency, while protein S deficiency activity < 70% was found 73.3.% (22 out of 30. On linear regression, the deterministic coefficient of AT-III activity deficiency to the development ACS was 13,25 %, and the deterministic coefficient of protein C activity deficient to the development of ACS was 9,06 %. The cut-off point for AT-III without protein S deficiency expected to contribute to the development of vessel disease was 45%. On discriminant analysis, protein C activity deficiency posed a risk for ACS of 4,5 greater than non deficient subjects, and AT-III activity deficiency posed a risk for ACS of 3,5 times greater than non deficient subjects. On binary logistic regression, protein S activity acted only as a reinforcing factor of AT-III activity deficiency in the development of ACS. Protein C and AT III deficiency can trigger ACS, with determinant coefficients of 9,06% and 13,25% respectively. Low levels of protein C posed a greater risk of

  5. Stimulation of DNA Glycosylase Activities by XPC Protein Complex: Roles of Protein-Protein Interactions

    Directory of Open Access Journals (Sweden)

    Yuichiro Shimizu

    2010-01-01

    Full Text Available We showed that XPC complex, which is a DNA damage detector for nucleotide excision repair, stimulates activity of thymine DNA glycosylase (TDG that initiates base excision repair. XPC appeared to facilitate the enzymatic turnover of TDG by promoting displacement from its own product abasic site, although the precise mechanism underlying this stimulation has not been clarified. Here we show that XPC has only marginal effects on the activity of E. coli TDG homolog (EcMUG, which remains bound to the abasic site like human TDG but does not significantly interacts with XPC. On the contrary, XPC significantly stimulates the activities of sumoylated TDG and SMUG1, both of which exhibit quite different enzymatic kinetics from unmodified TDG but interact with XPC. These results point to importance of physical interactions for stimulation of DNA glycosylases by XPC and have implications in the molecular mechanisms underlying mutagenesis and carcinogenesis in XP-C patients.

  6. Major cerebral events in Staphylococcus aureus infective endocarditis: is anticoagulant therapy safe?

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Snygg-Martin, Ulrika; Olaison, Lars;

    2009-01-01

    -hospital mortality was 23% (95% CI: 17-29%), and there was no significant difference between those with or without anticoagulation. CONCLUSIONS: We found no increased risk of cerebral haemorrhage in S. aureus IE patients receiving anticoagulation. Anticoagulation was associated with a reduced risk of cerebral events...... before initiation of antibiotics. Data support the continuance of anticoagulation in S. aureus IE patients when indicated.......OBJECTIVES: To study the impact of anticoagulation on major cerebral events in patients with left-sided Staphylococcus aureus infective endocarditis (IE). METHODS: A prospective cohort study; the use of anticoagulation and the relation to major cerebral events was evaluated separately at onset...

  7. Exosomes from myeloid derived suppressor cells carry biologically active proteins

    OpenAIRE

    Burke, Meghan; Choksawangkarn, Waeowalee; Edwards, Nathan; Ostrand-Rosenberg, Suzanne; Fenselau, Catherine

    2013-01-01

    Myeloid-derived suppressor cells (MDSC) are present in most cancer patients where they inhibit natural anti-tumor immunity and are an obstacle to anti-cancer immunotherapies. They mediate immune suppression through their production of proteins and soluble mediators that prevent the activation of tumor-reactive T lymphyocytes, polarize macrophages towards a tumor-promoting phenotype, and facilitate angiogenesis. The accumulation and suppressive potency of MDSC is regulated by inflammation with...

  8. Mitogen-activated protein kinases in the acute diabetic myocardium

    Czech Academy of Sciences Publication Activity Database

    Strnisková, M.; Barančík, M.; Neckář, Jan; Ravingerová, T.

    2003-01-01

    Roč. 249, 1-2 (2003), s. 59-65. ISSN 0300-8177 R&D Projects: GA MŠk LN00A069 Grant ostatní: VEGA(SK) 2/2063/22 Institutional research plan: CEZ:AV0Z5011922 Keywords : experimental diabetes * ischemia * mitogen-activated protein kinases (MAPK) Subject RIV: ED - Physiology Impact factor: 1.763, year: 2003

  9. Characterization of the Anticoagulative Constituents of Angelicae Sinensis Radix and Their Metabolites in Rats by HPLC-DAD-ESI-IT-TOF-MSn.

    Science.gov (United States)

    Wang, Lu; Huang, Shuai; Chen, Bing; Zang, Xin-Yu; Su, Dan; Liang, Jing; Xu, Feng; Liu, Guang-Xue; Shang, Ming-Ying; Cai, Shao-Qing

    2016-03-01

    Angelicae Sinensis Radix is commonly used in traditional Chinese medicine. Pharmacological studies show that Angelicae Sinensis Radix has clear anticoagulant activity. Therefore, in this study, the anticoagulant activity of crude Angelicae Sinensis Radix extracts was investigated by measuring the thrombin times of the extracts. The results revealed that the petroleum ether-soluble fraction of Angelicae Sinensis Radix exhibited significant anticoagulant activity in vitro, and 26 compounds were characterized by high-performance liquid chromatography with diode array detection combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry. In addition, 5 prototype constituents, 24 in vivo metabolites in rat urine and 7 prototype constituents, and 9 in vitro metabolites in the rat hepatic S9 incubation system of the petroleum ether-soluble fraction were tentatively identified. All metabolites were found from Angelicae Sinensis Radix for the first time. Among them, 13 (three ferulic acid-related constituents, six senkyunolide D-related constituents, and four senkyunolide F-related constituents) were identified as new metabolites (new compounds). This study is the first to qualitatively characterize the chemical constituents of the potent anticoagulative extract of Angelicae Sinensis Radix and to explore its metabolism. The result is a notable improvement in the discovery of Angelicae Sinensis Radix metabolites, and it provides the chemical basis for the effective forms and pharmacodynamic substances (prototypes, metabolites, or both) of the anticoagulant activity of Angelicae Sinensis Radix. PMID:26829520

  10. Study on antibacterial activity of hydrogel from irradiated silk protein

    International Nuclear Information System (INIS)

    Hydrogels for biomedical application were prepared from solution blends of 3% silk protein and 3%, 10% poly (vinyl alcohol) (PVA) and followed with irradiation. Mixture of hydrogels were gamma irradiated at 10, 20, 30, 40 and 50 kGy under N2 atmosphere. To clarify anti-bacterial activity of hydrogels, modified of the Agar disk diffusion method and American Association of Textile Chemists and Colorists, AATCC Test Method 90-1977, were carried out. The four kinds of bacteria such as Escherichia coli, Bacillus subtilis, Staphylococcus aureus and Staphylococcus epidermidis, were used. It was found that a 1:3 volume ratio of 3% silk protein and 3% PVA respectively, at 50 kGy irradiation, is suitable conditions for preparation hydrogels and trend to indicate the highest of an antibacterial activity against E. coli, B. subtilis and S. aureus. However the antibacterial activity of hydrogels against S. epidermidis was not clearly. These results are very useful to expand the application of hydrogel from irradiated silk protein to the medical products. (author)

  11. Study on antibacterial activity of hydrogel from irradiated silk protein

    Energy Technology Data Exchange (ETDEWEB)

    Bunnak, J.; Chaisupakitsin, M. [King Mongkut' s Institute of Technology Lardkrabang, Bangkok (Thailand)

    2001-03-01

    Hydrogels for biomedical application were prepared from solution blends of 3% silk protein and 3%, 10% poly (vinyl alcohol) (PVA) and followed with irradiation. Mixture of hydrogels were gamma irradiated at 10, 20, 30, 40 and 50 kGy under N{sub 2} atmosphere. To clarify anti-bacterial activity of hydrogels, modified of the Agar disk diffusion method and American Association of Textile Chemists and Colorists, AATCC Test Method 90-1977, were carried out. The four kinds of bacteria such as Escherichia coli, Bacillus subtilis, Staphylococcus aureus and Staphylococcus epidermidis, were used. It was found that a 1:3 volume ratio of 3% silk protein and 3% PVA respectively, at 50 kGy irradiation, is suitable conditions for preparation hydrogels and trend to indicate the highest of an antibacterial activity against E. coli, B. subtilis and S. aureus. However the antibacterial activity of hydrogels against S. epidermidis was not clearly. These results are very useful to expand the application of hydrogel from irradiated silk protein to the medical products. (author)

  12. Overinhibition of Mitogen-Activated Protein Kinase Inducing Tau Hyperphosphorylation

    Institute of Scientific and Technical Information of China (English)

    LI Hong-lian; CHEN Juan; LIU Shi-jie; ZHANG Jia-yu; WANG Qun; WANG Jian-zhi

    2005-01-01

    To reveal the relationship between mitogen-activated protein kinase (MAPK) and tau phosphorylation, we used different concentration of PD98059, an inhibitor of MEK (MAPK kinase), to treat mice neuroblastma (N2a) cell line for 6 h. It showed that the activity of MAPK decreased in a dose-dependent manner. But Western blot and immunofluorescence revealed that just when the cells were treated with 16 μmol/L PD98059, tau was hyperphosphorylated at Ser396/404 and Ser199/202 sites. We obtained the conclusion that overinhibited MAPK induced tau hyperphosphorylation at Ser396/404 and Ser199/202 sites.

  13. Effects of protein kinase C activators and staurosporine on protein kinase activity, cell survival, and proliferation in Tetrahymena thermophila

    DEFF Research Database (Denmark)

    Straarup, EM; Schousboe, P; Hansen, HQ;

    1997-01-01

    Autocrine factors prevent cell death in the ciliate Tetrahymena thermophila, a unicellular eukaryote, in a chemically defined medium. At certain growth conditions these factors are released at a sufficient concentration by > 500 cells ml-1 to support cell survival and proliferation. The protein...... kinase C activators phorbol 12-myristate 13-acetate (PMA) or 1-oleyl 2-acetate glycerol (OAG) when added to 250 cells ml-1 supported cell survival and proliferation. In the presence of the serine and threonine kinase inhibitor staurosporine the cells died both at 250 cells ml-1 in cultures supplemented...... with either PMA or OAG, or at 2,500 cells ml-1. At 500 cells ml-1 PMA induced the in vivo phosphorylation of at least six proteins. The myelin basic protein fragment 4-14 was phosphorylated in vitro in crude extracts of a culture of 250,000 cells ml-1. Both the in vivo and the in vitro phosphorylation...

  14. AMP-activated Protein Kinase Is Activated as a Consequence of Lipolysis in the Adipocyte

    Science.gov (United States)

    AMP-activated protein kinase (AMPK) is activated in adipocytes during exercise and other states in which lipolysis is stimulated. However, the mechanism(s) responsible for this effect and its physiological relevance are unclear. To examine these questions, 3T3-L1 adipocytes were treated with agents...

  15. Computational Modeling for the Activation Cycle of G-proteins by G-protein-coupled Receptors

    CERN Document Server

    Bao, Yifei; Glavy, Joseph; White, Tommy; 10.4204/EPTCS.40.4

    2010-01-01

    In this paper, we survey five different computational modeling methods. For comparison, we use the activation cycle of G-proteins that regulate cellular signaling events downstream of G-protein-coupled receptors (GPCRs) as a driving example. Starting from an existing Ordinary Differential Equations (ODEs) model, we implement the G-protein cycle in the stochastic Pi-calculus using SPiM, as Petri-nets using Cell Illustrator, in the Kappa Language using Cellucidate, and in Bio-PEPA using the Bio-PEPA eclipse plug in. We also provide a high-level notation to abstract away from communication primitives that may be unfamiliar to the average biologist, and we show how to translate high-level programs into stochastic Pi-calculus processes and chemical reactions.

  16. Survey of Botulinum Toxin Injections in Anticoagulated Patients: Korean Physiatrists' Preference in Controlling Anticoagulation Profile Prior to Intramuscular Injection

    Science.gov (United States)

    Jang, Yongjun; Park, Geun-Young; Park, Jihye; Choi, Asayeon; Kim, Soo Yeon; Boulias, Chris; Phadke, Chetan P.; Ismail, Farooq

    2016-01-01

    Objective To evaluate Korean physiatrists' practice of performing intramuscular botulinum toxin injection in anticoagulated patients and to assess their preference in controlling the bleeding risk before injection. Methods As part of an international collaboration survey study, a questionnaire survey was administered to 100 Korean physiatrists. Physiatrists were asked about their level of experience with botulinum toxin injection, the safe international normalized ratio range in anticoagulated patients undergoing injection, their tendency for injecting into deep muscles, and their experience of bleeding complications. Results International normalized ratio <2.0 was perceived as an ideal range for performing Botulinum toxin injection by 41% of the respondents. Thirty-six respondents replied that the international normalized ratio should be lowered to sub-therapeutic levels before injection, and 18% of the respondents reported that anticoagulants should be intentionally withheld and discontinued prior to injection. In addition, 20%–30% of the respondents answered that they were uncertain whether they should perform the injection regardless of the international normalized ratio values. About 69% of the respondents replied that they did have any standardized protocols for performing botulinum toxin injection in patients using anticoagulants. Only 1 physiatrist replied that he had encountered a case of compartment syndrome. Conclusion In accordance with the lack of consensus in performing intramuscular botulinum toxin injection in anticoagulated patients, our survey shows a wide range of practices among many Korean physiatrists; they tend to avoid botulinum toxin injection in anticoagulated patients and are uncertain about how to approach these patients. The results of this study emphasize the need for formulating a proper international consensus on botulinum toxin injection management in anticoagulated patients. PMID:27152278

  17. Activated protein synthesis and suppressed protein breakdown signaling in skeletal muscle of critically ill patients.

    Directory of Open Access Journals (Sweden)

    Jakob G Jespersen

    Full Text Available BACKGROUND: Skeletal muscle mass is controlled by myostatin and Akt-dependent signaling on mammalian target of rapamycin (mTOR, glycogen synthase kinase 3β (GSK3β and forkhead box O (FoxO pathways, but it is unknown how these pathways are regulated in critically ill human muscle. To describe factors involved in muscle mass regulation, we investigated the phosphorylation and expression of key factors in these protein synthesis and breakdown signaling pathways in thigh skeletal muscle of critically ill intensive care unit (ICU patients compared with healthy controls. METHODOLOGY/PRINCIPAL FINDINGS: ICU patients were systemically inflamed, moderately hyperglycemic, received insulin therapy, and showed a tendency to lower plasma branched chain amino acids compared with controls. Using Western blotting we measured Akt, GSK3β, mTOR, ribosomal protein S6 kinase (S6k, eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1, and muscle ring finger protein 1 (MuRF1; and by RT-PCR we determined mRNA expression of, among others, insulin-like growth factor 1 (IGF-1, FoxO 1, 3 and 4, atrogin1, MuRF1, interleukin-6 (IL-6, tumor necrosis factor α (TNF-α and myostatin. Unexpectedly, in critically ill ICU patients Akt-mTOR-S6k signaling was substantially higher compared with controls. FoxO1 mRNA was higher in patients, whereas FoxO3, atrogin1 and myostatin mRNAs and MuRF1 protein were lower compared with controls. A moderate correlation (r2=0.36, p<0.05 between insulin infusion dose and phosphorylated Akt was demonstrated. CONCLUSIONS/SIGNIFICANCE: We present for the first time muscle protein turnover signaling in critically ill ICU patients, and we show signaling pathway activity towards a stimulation of muscle protein synthesis and a somewhat inhibited proteolysis.

  18. Anticoagulant rodenticide poisoning in animals of Apulia and Basilicata, Italy.

    Science.gov (United States)

    Muscarella, Marilena; Armentano, Antonio; Iammarino, Marco; Palermo, Carmen; Amorena, Michele

    2016-06-30

    This study evaluates the presence of anticoagulant rodenticides in animals with a diagnosis of suspected poisoning and in bait samples. The survey was carried out from 2010 to 2012, in 2 regions of South Italy (Puglia and Basilicata) on 300 organs of animals and 90 suspected bait samples. The qualitative and quantitative analyses were conducted using an analytical method based on high‑performance liquid chromatography (HPLC) with fluorimetric detection (FLD) for the simultaneous determination of 8 anticoagulant rodenticides (bromadiolone, brodifacoum, coumachlor, coumafuryl, coumatetralyl, difenacoum, flocoumafen, and warfarin). The presence of anticoagulant rodenticides was detected in 33 organs of animals (11% of the total) and 6 bait samples (7% of the total). The most commonly detected compound was coumachlor (47% of 39 positive samples) followed by bromadiolone (24%), and brodifacoum (11%). The species mostly involved in anticoagulant rodenticide poisoning were dogs and cats. This study emphasizes the relevance of the determinations of anticoagulant rodenticides in cases of suspected poisoning in veterinary practice. PMID:27393877

  19. Retrospective evaluation of a pharmacist-managed warfarin anticoagulation clinic.

    Science.gov (United States)

    Garabedian-Ruffalo, S M; Gray, D R; Sax, M J; Ruffalo, R L

    1985-02-01

    The effectiveness of a pharmacist-managed warfarin anticoagulation clinic in maintaining therapeutic prothrombin times and preventing hospitalizations secondary to inadequate control of anticoagulation was evaluated. Patients who had received warfarin sodium for at least one year before being referred to the anticoagulation clinic were studied using retrospective chart reviews. Clinical pharmacists provided patient education, monitored patients for hemorrhagic and thromboembolic complications, and adjusted warfarin sodium dosage to maintain therapeutic prothrombin times. The patients' primary physicians retained responsibility for overall care and were consulted by pharmacists regarding complications of anticoagulation and patient unreliability. The percentage of patients requiring hospitalization (39% versus 4%) and the percentage of prothrombin times outside the therapeutic range (35.8% versus 14.4%) were significantly higher during the preclinic phase (before referral to the clinic) than during the clinic phase. Eight patients were hospitalized for hemorrhagic complications and four for thromboembolism during the preclinic phase; only one hospitalization for hemorrhage occurred during the clinic phase. The warfarin anticoagulation clinic staffed by specially trained pharmacists provided improved therapy compared with treatment received by patients before their referral to the clinic. PMID:3976675

  20. Antioxidative activity of protein hydrolysates prepared from alkaline-aided channel catfish protein isolates.

    Science.gov (United States)

    Theodore, Ann E; Raghavan, Sivakumar; Kristinsson, Hordur G

    2008-08-27

    Antioxidative activity of hydrolyzed protein prepared from alkali-solubilized catfish protein isolates was studied. The isolates were hydrolyzed to 5, 15, and 30% degree of hydrolysis using the protease enzyme, Protamex. Hydrolyzed protein was separated into hydrolysates and soluble supernatants, and both of these fractions were studied for their metal chelating ability, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and their ability to inhibit the formation of thiobarbituric acid reactive substances (TBARS) in washed tilapia muscle containing tilapia hemolysate. Both hydrolysates and supernatants were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Results showed that DPPH radical scavenging ability and reducing power of catfish protein hydrolysates decreased, whereas the ORAC value, metal chelating ability, and ability to inhibit TBARS increased, with an increase in the degree of hydrolysis. Hydrolysate samples showed higher DPPH radical scavenging ability and Fe(3+) reducing ability, and supernatant samples had higher metal chelating ability. In general, low molecular weight (MW) peptides had high ORAC values and high metal chelating ability, and high MW peptides had a higher reducing power (FRAP) and were more effective in scavenging DPPH radicals. In a washed muscle model system, the ability of catfish protein hydrolysates and their corresponding supernatants to inhibit the formation of TBARS increased with an increase in the degree of hydrolysis. PMID:18662014

  1. H pylori stimulates proliferation of gastric cancer cells through activating mitogen-activated protein kinase cascade

    Institute of Scientific and Technical Information of China (English)

    Yong-Chang Chen; Ying Wang; Jing-Yan Li; Wen-Rong Xu; You-Li Zhang

    2006-01-01

    AIM: To explore the mechanism by which H pylori causes activation of gastric epithelial cells.METHODS: A VacA (+) and CagA (+) standard Hpyloriline NCTC 11637 and a human gastric adenocarcinoma derived gastric epithelial cell line BGC-823 were applied in the study. MTT assay and 3H-TdR incorporation test were used to detect the proliferation of BGC-823 cells and Western blotting was used to detect the activity and existence of related proteins.RESULTS: Incubation with Hpylori extract increased the proliferation of gastric epithelial cells, reflected by both live cell number and DNA synthesis rate. The activity of extracellular signal-regulated protein kinase (ERK) signal transduction cascade increased within 20 min after incubation with Hpylori extract and appeared to be a sustained event. MAPK/ERK kinase (MEK) inhibitor PD98059abolished the action of H pylori extract on both ERK activity and cell proliferation. Incubation with H pyloriextract increased c-Fos expression and SRE-dependentgene expression. H pylori extract caused phosphorylation of several proteins including a protein with molecular size of 97.4 kDa and tyrosine kinase inhibitor genistein inhibited the activation of ERK and the proliferation of cells caused by H pylori extract.CONCLUSION: Biologically active elements in H pylori extract cause proliferation of gastric epithelial cells through activating tyrosine kinase and ERK signal transduction cascade.

  2. Berberine Promotes Glucose Consumption Independently of AMP-Activated Protein Kinase Activation

    OpenAIRE

    Miao Xu; Yuanyuan Xiao; Jun Yin; Wolin Hou; Xueying Yu; Li Shen; Fang Liu; Li Wei; Weiping Jia

    2014-01-01

    Berberine is a plant alkaloid with anti-diabetic action. Activation of AMP-activated protein kinase (AMPK) pathway has been proposed as mechanism for berberine's action. This study aimed to examine whether AMPK activation was necessary for berberine's glucose-lowering effect. We found that in HepG2 hepatocytes and C2C12 myotubes, berberine significantly increased glucose consumption and lactate release in a dose-dependent manner. AMPK and acetyl coenzyme A synthetase (ACC) phosphorylation wer...

  3. Involvement of Hypothalamic AMP-Activated Protein Kinase in Leptin-Induced Sympathetic Nerve Activation

    OpenAIRE

    Mamoru Tanida; Naoki Yamamoto; Toshishige Shibamoto; Kamal Rahmouni

    2013-01-01

    In mammals, leptin released from the white adipose tissue acts on the central nervous system to control feeding behavior, cardiovascular function, and energy metabolism. Central leptin activates sympathetic nerves that innervate the kidney, adipose tissue, and some abdominal organs in rats. AMP-activated protein kinase (AMPK) is essential in the intracellular signaling pathway involving the activation of leptin receptors (ObRb). We investigated the potential of AMPKα2 in the sympathetic effec...

  4. Cordycepin activates AMP-activated protein kinase (AMPK) via interaction with the γ1 subunit

    OpenAIRE

    Wu, Chongming; Guo, Yanshen; Su, Yan; Zhang, Xue; Luan, Hong; Zhang, Xiaopo; Zhu, Huixin; He, Huixia; Wang, Xiaoliang; Sun, Guibo; Sun, Xiaobo; Guo, Peng; Zhu, Ping

    2013-01-01

    Cordycepin is a bioactive component of the fungus Cordyceps militaris. Previously, we showed that cordycepin can alleviate hyperlipidemia through enhancing the phosphorylation of AMP-activated protein kinase (AMPK), but the mechanism of this stimulation is unknown. Here, we investigated the potential mechanisms of cordycepin-induced AMPK activation in HepG2 cells. Treatment with cordycepin largely reduced oleic acid (OA)-elicited intracellular lipid accumulation and increased AMPK activity in...

  5. Conservation, variability and the modeling of active protein kinases.

    Directory of Open Access Journals (Sweden)

    James D R Knight

    Full Text Available The human proteome is rich with protein kinases, and this richness has made the kinase of crucial importance in initiating and maintaining cell behavior. Elucidating cell signaling networks and manipulating their components to understand and alter behavior require well designed inhibitors. These inhibitors are needed in culture to cause and study network perturbations, and the same compounds can be used as drugs to treat disease. Understanding the structural biology of protein kinases in detail, including their commonalities, differences and modes of substrate interaction, is necessary for designing high quality inhibitors that will be of true use for cell biology and disease therapy. To this end, we here report on a structural analysis of all available active-conformation protein kinases, discussing residue conservation, the novel features of such conservation, unique properties of atypical kinases and variability in the context of substrate binding. We also demonstrate how this information can be used for structure prediction. Our findings will be of use not only in understanding protein kinase function and evolution, but they highlight the flaws inherent in kinase drug design as commonly practiced and dictate an appropriate strategy for the sophisticated design of specific inhibitors for use in the laboratory and disease therapy.

  6. Superoxide dismutase activity of Cu-bound prion protein

    Science.gov (United States)

    Hodak, Miroslav; Lu, Wenchang; Bernholc, Jerry

    2009-03-01

    Misfolding of the prion protein, PrP, has been linked to a group of neurodegenerative diseases, including the mad cow disease in cattle and the Creutzfeldt-Jakob disease in humans. The normal function of PrP is still unknown, but it was found that the PrP can efficiently bind Cu(II) ions. Early experiments suggested that Cu-PrP complex possesses significant superoxide dismutase (SOD) activity, but later experiments failed to confirm it and at present this issue remains unresolved. Using a recently developed hybrid DFT/DFT method, which combines Kohn-Sham DFT for the solute and its first solvation shells with orbital-free DFT for the remainder of the solvent, we have investigated SOD activity of PrP. The PrP is capable of incorporating Cu(II) ions in several binding modes and our calculations find that each mode has a different SOD activity. The highest activity found is comparable to those of well-known SOD proteins, suggesting that the conflicting experimental results may be due to different bindings of Cu(II) in those experiments.

  7. Adherence to oral anticoagulant therapy in secondary stroke prevention – impact of the novel oral anticoagulants

    Directory of Open Access Journals (Sweden)

    Luger S

    2015-11-01

    Full Text Available Sebastian Luger,1 Carina Hohmann,2 Daniela Niemann,1 Peter Kraft,3 Ignaz Gunreben,3 Tobias Neumann-Haefelin,2 Christoph Kleinschnitz,3 Helmuth Steinmetz,1 Christian Foerch,1 Waltraud Pfeilschifter1 1Department of Neurology, University Hospital Frankfurt, Frankfurt am Main, 2Department of Neurology, Klinikum Fulda gAG, Fulda, 3Department of Neurology, University Hospital Würzburg, Würzburg, Germany Background: Oral anticoagulant therapy (OAT potently prevents strokes in patients with atrial fibrillation. Vitamin K antagonists (VKA have been the standard of care for long-term OAT for decades, but non-VKA oral anticoagulants (NOAC have recently been approved for this indication, and raised many questions, among them their influence on medication adherence. We assessed adherence to VKA and NOAC in secondary stroke prevention. Methods: All patients treated from October 2011 to September 2012 for ischemic stroke or transient ischemic attack with a subsequent indication for OAT, at three academic hospitals were entered into a prospective registry, and baseline data and antithrombotic treatment at discharge were recorded. At the 1-year follow-up, we assessed the adherence to different OAT strategies and patients’ adherence to their respective OAT. We noted OAT changes, reasons to change treatment, and factors that influence persistence to the prescribed OAT. Results: In patients discharged on OAT, we achieved a fatality corrected response rate of 73.3% (n=209. A total of 92% of these patients received OAT at the 1-year follow-up. We observed good adherence to both VKA and NOAC (VKA, 80.9%; NOAC, 74.8%; P=0.243 with a statistically nonsignificant tendency toward a weaker adherence to dabigatran. Disability at 1-year follow-up was an independent predictor of lower adherence to any OAT after multivariate analysis, whereas the choice of OAT did not have a relevant influence. Conclusion: One-year adherence to OAT after stroke is strong (>90% and patients

  8. Fluctuation driven active molecular transport in passive channel proteins

    Science.gov (United States)

    Kosztin, Ioan

    2006-03-01

    Living cells interact with their extracellular environment through the cell membrane, which acts as a protective permeability barrier for preserving the internal integrity of the cell. However, cell metabolism requires controlled molecular transport across the cell membrane, a function that is fulfilled by a wide variety of transmembrane proteins, acting as either passive or active transporters. In this talk it is argued that, contrary to the general belief, in active cell membranes passive and spatially asymmetric channel proteins can act as active transporters by consuming energy from nonequilibrium fluctuations fueled by cell metabolism. This assertion is demonstrated in the case of the E. coli aquaglyceroporin GlpF channel protein, whose high resolution crystal structure is manifestly asymmetric. By calculating the glycerol flux through GlpF within the framework of a stochastic model, it is found that, as a result of channel asymmetry, glycerol uptake driven by a concentration gradient is enhanced significantly in the presence of non-equilibrium fluctuations. Furthermore, the enhancement caused by a ratchet-like mechanism is larger for the outward, i.e., from the cytoplasm to the periplasm, flux than for the inward one, suggesting that the same non-equilibrium fluctuations also play an important role in protecting the interior of the cell against poisoning by excess uptake of glycerol. Preliminary data on water and sugar transport through aquaporin and maltoporin channels, respectively, are indicative of the universality of the proposed nonequilibrium-fluctuation-driven active transport mechanism. This work was supported by grants from the Univ. of Missouri Research Board, the Institute for Theoretical Sciences and the Department of Energy (DOE Contract W-7405-ENG-36), and the National Science Foundation (FIBR-0526854).

  9. Mitogen-activated protein kinase (MAPK) in cardiac tissues.

    Science.gov (United States)

    Page, C; Doubell, A F

    Mitogen-activated protein kinase (MAPK) has recently emerged as a prominent role player in intracellular signalling in the ventricular myocyte with attention being focussed on its possible role in the development of ventricular hypertrophy. It is becoming clear that MAPK is also active in other cells of cardiac origin such as cardiac fibroblasts and possible functions of this signalling pathway in the heart have yet to be explored. In this report the mammalian MAPK pathway is briefly outlined, before reviewing current knowledge of the MAPK pathway in cardiac tissue (ventricular myocytes, vascular smooth muscle cells and cardiac fibroblasts). New data is also presented on the presence and activity of MAPK in two additional cardiac celltypes namely atrial myocytes and vascular endothelial cells from the coronary microcirculation. PMID:8739228

  10. Zinc ions bind to and inhibit activated protein C

    DEFF Research Database (Denmark)

    Zhu, Tianqing; Ubhayasekera, Wimal; Nickolaus, Noëlle;

    2010-01-01

    Zn2+ ions were found to efficiently inhibit activated protein C (APC), suggesting a potential regulatory function for such inhibition. APC activity assays employing a chromogenic peptide substrate demonstrated that the inhibition was reversible and the apparent K I was 13 +/- 2 microM. k cat was...... seven fold decreased whereas K M was unaffected in the presence of 10 microM Zn2+. The inhibitory effect of Zn2+ on APC activity was also observed when factor Va was used as a substrate in an assay coupled to a prothrombinase assay. The interaction of Zn2+ with APC was accompanied by a reversible...... fold enhanced, presumably due to the Ca2+-induced conformational change affecting the conformation of the Zn2+-binding site. The inhibition mechanism was non-competitive both in the absence and presence of Ca2+. Comparisons of sequences and structures suggested several possible sites for zinc binding...

  11. Mycobacteriophage putative GTPase-activating protein can potentiate antibiotics.

    Science.gov (United States)

    Yan, Shuangquan; Xu, Mengmeng; Duan, Xiangke; Yu, Zhaoxiao; Li, Qiming; Xie, Longxiang; Fan, Xiangyu; Xie, Jianping

    2016-09-01

    The soaring incidences of infection by antimicrobial resistant (AR) pathogens and shortage of effective antibiotics with new mechanisms of action have renewed interest in phage therapy. This scenario is exemplified by resistant tuberculosis (TB), caused by resistant Mycobacterium tuberculosis. Mycobacteriophage SWU1 A321_gp67 encodes a putative GTPase-activating protein. Mycobacterium smegmatis with gp67 overexpression showed changed colony formation and biofilm morphology and supports the efficacy of streptomycin and capreomycin against Mycobacterium. gp67 down-regulated the transcription of genes involved in cell wall and biofilm development. To our knowledge, this is the first report to show that phage protein in addition to lysin or recombination components can synergize with existing antibiotics. Phage components might represent a promising new clue for better antibiotic potentiators. PMID:27345061

  12. A pharmacologic overview of current and emerging anticoagulants.

    Science.gov (United States)

    Nutescu, Edith A; Shapiro, Nancy L; Chevalier, Aimee; Amin, Alpesh N

    2005-04-01

    For over 50 years, anticoagulant options for the treatment and prevention of thrombosis have been limited mainly to traditional agents such as unfractionated heparin and oral vitamin K antagonists such as warfarin. These traditional agents are fraught with limitations that complicate their clinical use. A variety of novel anticoagulants with improved pharmacologic and clinical profiles have recently been introduced or are in development, offering benefits over traditional therapies. Specifically, progress has been made in the development of low-molecular-weight heparins, factor Xa inhibitors, and direct thrombin inhibitors. Because of their convenience and ease of use, some of these novel compounds are competing with the traditional anticoagulants and are needed additions to the antithrombotic arsenal. PMID:15853173

  13. Plasma cholesteryl ester transfer protein mass and phospholipid transfer protein activity are associated with leptin in type 2 diabetes mellitus

    NARCIS (Netherlands)

    Dullaart, R. P. F.; de Vries, R.; Dallinga-Thie, G. M.; van Tol, A.; Sluiter, W. J.

    2007-01-01

    Adipose tissue contributes to plasma levels of lipid transfer proteins and is also the major source of plasma adipokines. We hypothesized that plasma cholesteryl ester transfer protein (CETP) mass, phospholipid transfer protein (PLTP) activity and cholesteryl ester transfer (CET, a measure of CETP a

  14. Personalized antiplatelet and anticoagulation therapy: applications and significance of pharmacogenomics

    Directory of Open Access Journals (Sweden)

    Beitelshees AL

    2015-02-01

    Full Text Available Amber L Beitelshees,1,* Deepak Voora,2,* Joshua P Lewis,1,* 1Program for Personalized and Genomic Medicine and Division of Endocrinology, Diabetes, and Nutrition, University of Maryland School of Medicine, Baltimore, MD, USA; 2Center for Applied Genomics & Precision Medicine, Department of Medicine, Duke School of Medicine, Durham, NC, USA*All authors contributed equally to this work Abstract: In recent years, substantial effort has been made to better understand the influence of genetic factors on the efficacy and safety of numerous medications. These investigations suggest that the use of pharmacogenetic data to inform physician decision-making has great potential to enhance patient care by reducing on-treatment clinical events, adverse drug reactions, and health care-related costs. In fact, integration of such information into the clinical setting may be particularly applicable for antiplatelet and anticoagulation therapeutics, given the increasing body of evidence implicating genetic variation in variable drug response. In this review, we summarize currently available pharmacogenetic information for the most commonly used antiplatelet (ie, clopidogrel and aspirin and anticoagulation (ie, warfarin medications. Furthermore, we highlight the currently known role of genetic variability in response to next-generation antiplatelet (prasugrel and ticagrelor and anticoagulant (dabigatran agents. While compelling evidence suggests that genetic variants are important determinants of antiplatelet and anticoagulation therapy response, significant barriers to clinical implementation of pharmacogenetic testing exist and are described herein. In addition, we briefly discuss development of new diagnostic targets and therapeutic strategies as well as implications for enhanced patient care. In conclusion, pharmacogenetic testing can provide important information to assist clinicians with prescribing the most personalized and effective antiplatelet and

  15. Evaluating the impact of new anticoagulants in the hospital setting

    Directory of Open Access Journals (Sweden)

    Braidy N

    2011-03-01

    Full Text Available The short-comings of current anticoagulants have led to the development of newer, albeit more expensive, oral alternatives.Objective: To explore the potential impact the new anticoagulants dabigatran and rivaroxaban in the local hospital setting, in terms of utilisation and subsequent costing.Method: A preliminary costing analysis was performed based on a prospective 2-week clinical audit (29th June - 13th July 2009. Data regarding current anticoagulation management were extracted from the medical files of patients admitted to Ryde Hospital. To model potential costing implications of using the newer agents, the reported incidence of VTE/stroke and bleeding events were obtained from key clinical trials.Results: Data were collected for 67 patients treated with either warfarin (n=46 or enoxaparin (n=21 for prophylaxis of VTE/stroke. At least two-thirds of all patients were deemed suitable candidates for the use of newer oral anticoagulants (by current therapy: warfarin: 65.2% (AF, 34.8% (VTE; enoxaparin: 100%, (VTE. The use of dabigatran in VTE/stroke prevention was found to be more cost-effective than warfarin and enoxaparin due to significantly lower costs of therapeutic monitoring and reduced administration costs. Rivaroxaban was more cost-effective than warfarin and enoxaparin for VTE/stroke prevention when supplier-rebates (33% were factored into costing.Conclusion: This study highlights the potential cost-effectiveness of newer anticoagulants, dabigatran and rivaroxaban, compared to warfarin and enoxaparin. These agents may offer economic advantages, as well as clinical benefits, in the hospital-based management of anticoagulated patients.

  16. Genome activation by raspberry bushy dwarf virus coat protein.

    Science.gov (United States)

    Macfarlane, Stuart A; McGavin, Wendy J

    2009-03-01

    Two sets of infectious cDNA clones of raspberry bushy dwarf virus (RBDV) have been constructed, enabling either the synthesis of infectious RNA transcripts or the delivery of infectious binary plasmid DNA by infiltration of Agrobacterium tumefaciens. In whole plants and in protoplasts, inoculation of RBDV RNA1 and RNA2 transcripts led to a low level of infection, which was greatly increased by the addition of RNA3, a subgenomic RNA coding for the RBDV coat protein (CP). Agroinfiltration of RNA1 and RNA2 constructs did not produce a detectable infection but, again, inclusion of a construct encoding the CP led to high levels of infection. Thus, RBDV replication is greatly stimulated by the presence of the CP, a mechanism that also operates with ilarviruses and alfalfa mosaic virus, where it is referred to as genome activation. Mutation to remove amino acids from the N terminus of the CP showed that the first 15 RBDV CP residues are not required for genome activation. Other experiments, in which overlapping regions at the CP N terminus were fused to the monomeric red fluorescent protein, showed that sequences downstream of the first 48 aa are not absolutely required for genome activation. PMID:19218221

  17. Comparison of pharmacist managed anticoagulation with usual medical care in a family medicine clinic

    OpenAIRE

    Dillon Carla; Twells Laurie; Bishop Lisa; Young Stephanie; Hawboldt John; O'Shea Patrick

    2011-01-01

    Abstract Background The beneficial outcomes of oral anticoagulation therapy are dependent upon achieving and maintaining an optimal INR therapeutic range. There is growing evidence that better outcomes are achieved when anticoagulation is managed by a pharmacist with expertise in anticoagulation management rather than usual care by family physicians. This study compared a pharmacist managed anticoagulation program (PC) to usual physician care (UC) in a family medicine clinic. Methods A retros...

  18. Novel oral anticoagulants in the treatment of cerebral venous thrombosis

    DEFF Research Database (Denmark)

    Feher, G; Illes, Z; Komoly, S; Hargroves, D

    2015-01-01

    (NOACs) have been extensively studied in patients with deep vein thrombosis (DVT), pulmonary embolism (PE) and non-valvular atrial fibrillation (NVAF). The aim of our work to review the available evidence for NOACs in the treatment of CVT. Based on our literature search there is insufficient evidence to......Cerebral venous thrombosis (CVT) is an uncommon cause of stroke with extremely diverse clinical features, predisposing factors, brain imaging findings, and outcome. Anticoagulation is the cornerstone of CVT management, however, it is not supported by high-quality evicence. Novel oral anticoagulants...

  19. Novel oral anticoagulants in the treatment of cerebral venous thrombosis.

    Science.gov (United States)

    Feher, Gergely; Illes, Zsolt; Komoly, Samuel; Hargroves, David

    2016-08-01

    Cerebral venous thrombosis (CVT) is an uncommon cause of stroke with extremely diverse clinical features, predisposing factors, brain imaging findings, and outcome. Anticoagulation is the cornerstone of CVT management, however, it is not supported by high-quality evicence. Novel oral anticoagulants (NOACs) have been extensively studied in patients with deep vein thrombosis, pulmonary embolism and non-valvular atrial fibrillation. The aim of our work was to review the available evidence for NOACs in the treatment of CVT. Based on our literature search there is insufficient evidence to support the use of NOACs in CVT, although case series with rivaroxaban and dabigatran have showed promising results. PMID:25994451

  20. Management of acute stroke in patients taking novel oral anticoagulants

    OpenAIRE

    Hankey, Graeme J; Norrving, Bo; Hacke, Werner; Steiner, Thorsten

    2014-01-01

    Each year, 1·0–2·0% of individuals with atrial fibrillation and 0·1–0·2% of those with venous thromboembolism who are receiving one of the novel oral anticoagulants (dabigatran, rivaroxaban, or apixaban) can be expected to experience an acute ischemic stroke. Additionally, 0·2–0·5% of individuals with atrial fibrillation who are receiving one of the novel oral anticoagulants can be expected to experience an intracranial hemorrhage. This opinion piece addresses the current literature and offer...

  1. Citrate anticoagulation for continuous renal replacement therapy in small children

    OpenAIRE

    Soltysiak, Jolanta; Warzywoda, Alfred; Kociński, Bartłomiej; Ostalska-Nowicka, Danuta; Benedyk, Anna; Silska-Dittmar, Magdalena; Zachwieja, Jacek

    2013-01-01

    Background Regional citrate anticoagulation (RCA) is one of the methods used to prevent clotting in continuous renal replacement therapy (CRRT). The aim of this study was to describe the outcomes and complications of RCA-CRRT in comparison to heparin anticoagulation (HA)-CRRT in critically ill children. Methods This study was a retrospective review of 30 critically ill children (16 on RCA- and 14 on HA-CRRT) who underwent at least 24 h of CRRT. The mean body weight of the children was 8.69 ± ...

  2. [Serious surgical complications associated with chronic anticoagulant therapy].

    Science.gov (United States)

    Pitrák, V; Hadacová, I; Hochová, I; Hoch, J

    2001-06-01

    Chronic anticoagulant treatment is administered mostly for cardiological reasons. Cumarin derivatires are used in the majority of cases (Warfarin, Pelentan). It is necessary to monitor this treatment regularly and to control the dose according to the INR value. Different complications can occur; the haemorrhage represents a serious one. The authors discuss several aspects of anticoagulant therapy and possible prevention of the complications. The importance of the problems is demonstrated on the authors' clinical experience--two cases of haemorrhage after Warfarin administration simulating an acute surgical event. PMID:11482149

  3. Immersion freezing of ice nucleation active protein complexes

    Directory of Open Access Journals (Sweden)

    S. Hartmann

    2013-06-01

    Full Text Available Utilising the Leipzig Aerosol Cloud Interaction Simulator (LACIS, the immersion freezing behaviour of droplet ensembles containing monodisperse particles, generated from a Snomax™ solution/suspension, was investigated. Thereto ice fractions were measured in the temperature range between −5 °C to −38 °C. Snomax™ is an industrial product applied for artificial snow production and contains Pseudomonas syringae} bacteria which have long been used as model organism for atmospheric relevant ice nucleation active (INA bacteria. The ice nucleation activity of such bacteria is controlled by INA protein complexes in their outer membrane. In our experiments, ice fractions increased steeply in the temperature range from about −6 °C to about −10 °C and then levelled off at ice fractions smaller than one. The plateau implies that not all examined droplets contained an INA protein complex. Assuming the INA protein complexes to be Poisson distributed over the investigated droplet populations, we developed the CHESS model (stoCHastic modEl of similar and poiSSon distributed ice nuclei which allows for the calculation of ice fractions as function of temperature and time for a given nucleation rate. Matching calculated and measured ice fractions, we determined and parameterised the nucleation rate of INA protein complexes exhibiting class III ice nucleation behaviour. Utilising the CHESS model, together with the determined nucleation rate, we compared predictions from the model to experimental data from the literature and found good agreement. We found that (a the heterogeneous ice nucleation rate expression quantifying the ice nucleation behaviour of the INA protein complex is capable of describing the ice nucleation behaviour observed in various experiments for both, Snomax™ and P. syringae bacteria, (b the ice nucleation rate, and its temperature dependence, seem to be very similar regardless of whether the INA protein complexes inducing ice

  4. Redox regulation of the AMP-activated protein kinase.

    Directory of Open Access Journals (Sweden)

    Yingying Han

    Full Text Available Redox state is a critical determinant of cell function, and any major imbalances can cause severe damage or death.The aim of this study is to determine if AMP-activated protein kinase (AMPK, a cellular energy sensor, is activated by oxidants generated by Berberine in endothelial cells (EC.Bovine aortic endothelial cells (BAEC were exposed to Berberine. AMPK activity and reactive oxygen species were monitored after the incubation.In BAEC, Berberine caused a dose- and time-dependent increase in the phosphorylation of AMPK at Thr172 and acetyl CoA carboxylase (ACC at Ser79, a well characterized downstream target of AMPK. Concomitantly, Berberine increased peroxynitrite, a potent oxidant formed by simultaneous generation of superoxide and nitric oxide. Pre-incubation of BAEC with anti-oxidants markedly attenuated Berberine-enhanced phosphorylation of both AMPK and ACC. Consistently, adenoviral expression of superoxide dismutase and pretreatment of L-N(G-Nitroarginine methyl ester (L-NAME; a non-selective NOS inhibitor blunted Berberine-induced phosphorylation of AMPK. Furthermore, mitochondria-targeted tempol (mito-tempol pretreatment or expression of uncoupling protein attenuated AMPK activation caused by Berberine. Depletion of mitochondria abolished the effects of Berberine on AMPK in EC. Finally, Berberine significantly increased the phosphorylation of LKB1 at Ser307 and gene silencing of LKB1 attenuated Berberine-enhanced AMPK Thr172 phosphorylation in BAEC.Our results suggest that mitochondria-derived superoxide anions and peroxynitrite are required for Berberine-induced AMPK activation in endothelial cells.

  5. Protein composition of catalytically active human telomerase from immortal cells

    DEFF Research Database (Denmark)

    Cohen, Scott B; Graham, Mark E; Lovrecz, George O;

    2007-01-01

    Telomerase is a ribonucleoprotein enzyme complex that adds 5'-TTAGGG-3' repeats onto the ends of human chromosomes, providing a telomere maintenance mechanism for approximately 90% of human cancers. We have purified human telomerase approximately 10(8)-fold, with the final elution dependent on the...... enzyme's ability to catalyze nucleotide addition onto a DNA oligonucleotide of telomeric sequence, thereby providing specificity for catalytically active telomerase. Mass spectrometric sequencing of the protein components and molecular size determination indicated an enzyme composition of two molecules...... each of telomerase reverse transcriptase, telomerase RNA, and dyskerin....

  6. Monomeric G protein-coupled receptor rhodopsin in solution activates its G protein transducin at the diffusion limit

    OpenAIRE

    Ernst, Oliver P.; Gramse, Verena; Kolbe, Michael; Hofmann, Klaus Peter; Heck, Martin

    2007-01-01

    G protein-coupled receptors mediate biological signals by stimulating nucleotide exchange in heterotrimeric G proteins (Gαβγ). Receptor dimers have been proposed as the functional unit responsible for catalytic interaction with Gαβγ. To investigate whether a G protein-coupled receptor monomer can activate Gαβγ, we used the retinal photoreceptor rhodopsin and its cognate G protein transducin (Gt) to determine the stoichiometry of rhodopsin/Gt binding and the rate of catalyzed nucleotide exchan...

  7. APPLICATIONS OF PHARMACOGENETIC TESTING FOR PERSONALIZATION OF THERAPY WITH ORAL ANTICOAGULANTS IN RUSSIA

    Directory of Open Access Journals (Sweden)

    D. A. Sychev

    2015-09-01

    Full Text Available The clinical significance of the patient genetic characteristics in the individual pharmacological response to oral anticoagulants is considered. Possible tactics of warfarin dosing and new oral anticoagulants choice on the basis of pharmacogenetic testing as well as indications for this approach in clinical practice are discussed. It should increase efficacy and safety of anticoagulant therapy.

  8. Molecular mechanism by which AMP-activated protein kinase activation promotes glycogen accumulation in muscle

    DEFF Research Database (Denmark)

    Hunter, Roger W; Treebak, Jonas Thue; Wojtaszewski, Jørgen;

    2011-01-01

    OBJECTIVE During energy stress, AMP-activated protein kinase (AMPK) promotes glucose transport and glycolysis for ATP production, while it is thought to inhibit anabolic glycogen synthesis by suppressing the activity of glycogen synthase (GS) to maintain the energy balance in muscle. Paradoxically...... transgenic mice overexpressing a kinase dead (KD) AMPK were incubated with glucose tracers and the AMPK-activating compound 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) ex vivo. GS activity and glucose uptake and utilization (glycolysis and glycogen synthesis) were assessed. RESULTS Even though...

  9. Physical activity and high-sensitivity C-reactive protein.

    Science.gov (United States)

    Plaisance, Eric P; Grandjean, Peter W

    2006-01-01

    Cardiovascular disease (CVD) remains one of the leading causes of death and disability in developed countries around the world despite the documented success of lifestyle and pharmacological interventions. This illustrates the multifactorial nature of atherosclerosis and the use of novel inflammatory markers as an adjunct to risk factor reduction strategies. As evidence continues to accumulate that inflammation is involved in all stages of the development and progression of atherosclerosis, markers of inflammation such as high-sensitivity C-reactive protein (CRP) may provide additional information regarding the biological status of the atherosclerotic lesion. Recent investigations suggest that physical activity reduces CRP levels. Higher levels of physical activity and cardiorespiratory fitness are consistently associated with 6-35% lower CRP levels. Longitudinal training studies that have demonstrated reductions in CRP concentrations range from 16% to 41%, an effect that may be independent of baseline levels of CRP, body composition or weight loss. The average change in CRP associated with physical activity appears to be at least as good, if not better, than currently prescribed pharmacological interventions in similar populations. The primary purpose of this review will be to present evidence from both cross-sectional and longitudinal investigations that physical activity lowers CRP levels in a dose-response manner. Finally, this review will examine factors such as body composition, sex, blood sample timing, diet and smoking, which may influence the CRP response to physical activity. PMID:16646631

  10. Gene activation by triplex-forming oligonucleotide coupled to the activating domain of protein VP16.

    OpenAIRE

    Kuznetsova, S.; Ait-Si-Ali, S; Nagibneva, I; Troalen, F; Le Villain, J P; Harel-Bellan, A; Svinarchuk, F

    1999-01-01

    Triplex-forming oligonucleotides (TFOs) are generally designed to inhibit transcription or DNA replication but can be used for more diverse purposes. Here we have designed a chimera peptide-TFO able to activate transcription from a target gene. The designed hybrid molecule contains a triplex-forming sequence, linked through a phosphoroamidate bond to several minimal transcriptional activation domains derived from Herpes simplex virus protein 16 (VP16). We show here that this TFO-peptide chime...

  11. Cutaneous necrosis in pregnancy secondary to activated protein C resistance in hereditary angioedema.

    Science.gov (United States)

    Perkins, W; Downie, I; Keefe, M; Chisholm, M

    1995-04-01

    A 26-year-old woman with hereditary angineurotic oedema (HAE) presented at 22 weeks gestation with severe cutaneous necrosis similar to that seen in coumarin skin necrosis. Protein S deficiency secondary to HAE and pregnancy was postulated. Treatment with heparin, C1-inhibitor concentrates, systemic steroids and surgical debridement resulted in a successful outcome for both mother and child. Subsequent investigations revealed normal levels of protein C, antithrombin III, total protein S, free protein S but reduced function protein S activity with evidence of activated protein C resistance. Cutaneous necrosis has not been reported in associated with activated protein C resistance previously and the possible mechanisms are discussed. PMID:7745572

  12. Lupus anticoagulant: a unique case with lupus anticoagulant and habitual abortion together with antifactor II antibody and bleeding tendency.

    Science.gov (United States)

    Stormorken, H; Gjemdal, T; Bjøro, K

    1988-01-01

    Lupus anticoagulants (LA) are associated with various forms of thrombotic events. Of particular interest to obstetrics is the association with placental infarcts and habitual abortion. In the case described a near full-term viable infant was delivered subsequent to four early miscarriages. However, the mother had then developed an antifactor II antibody leading to grave hypoprothrombinemia with bleeding tendency, indicating efficient autoanticoagulation. This natural experiment indicates that these patients should receive anticoagulation during pregnancy, possibly in combination with steroids to depress the LA level. PMID:3139508

  13. Regulation of mitogen-activated protein kinase 3/1 activity during meiosis resumption in mammals

    Czech Academy of Sciences Publication Activity Database

    Procházka, Radek; Blaha, Milan

    2015-01-01

    Roč. 61, č. 6 (2015), s. 495-502. ISSN 0916-8818 R&D Projects: GA MZe(CZ) QJ1510138 Institutional support: RVO:67985904 Keywords : cumulus oocyte complexes * meiosis resumption * mitogen-activated protein kinase 3/1 (MAPK3/1) Subject RIV: GI - Animal Husbandry ; Breeding Impact factor: 1.515, year: 2014

  14. Natural coagulation inhibitors and active protein c resistance in preeclampsia

    Directory of Open Access Journals (Sweden)

    Cengiz Demir

    2010-01-01

    Full Text Available INTRODUCTION: The etiology of preeclampsia is not fully established. A few studies have shown a relationship between natural coagulation inhibitors and preeclampsia. OBJECTIVES: The purpose of this study was to investigate the status of natural coagulation inhibitors and active protein C resistance (APC-R in preeclampsia. PATIENTS AND METHODS: We studied 70 women with preeclampsia recruited consecutively and 70 healthy pregnant and 70 nonpregnant women as controls. Plasma protein C (PC, free protein S (fPS, antithrombin III (ATIII and APC-R were evaluated. RESULTS: ATIII values were found to be significantly lower in preeclamptic patients than in the control groups (p< 0.001. Nevertheless, there was no significant difference between the healthy pregnant and nonpregnant women groups (p=0.141. The fPS values of the preeclamptic and healthy pregnant groups were lower than that of the nonpregnant group (p< 0.001, and the fPS value of the preeclamptic pregnant women was lower than that of healthy pregnant women (p<0.001. The PC value of the preeclamptic pregnant women was lower than that of the control groups (p< 0.001. The PC value of the healthy pregnant women was lower than that of the nonpregnant women (p< 0.001. The mean APC activity values were lower in the preeclamptic patients than that of the control groups (p< 0.001, p< 0.001. The APC-R positivity rates of the preeclamptic groups were higher than that of the control groups (p<0.001. CONCLUSIONS: This study demonstrated that ATIII, fPS, PC values and APC resistance were lower and APC-R positivity was higher in preeclamptic women than in normal pregnant and nonpregnant women.

  15. Perioperative anticoagulation for children with prosthetic mechanical valves.

    Science.gov (United States)

    Rees, P; Grech, V

    2000-04-01

    The insertion of a mechanical heart valve predisposes to thrombosis and embolism, and for this reason, individuals with mechanical valves who undergo dental/surgical procedures must take special precautions. In this article, we illustrate a protocol for anticoagulation during such procedures in individuals with mechanical valves. PMID:22368581

  16. Do we have to anticoagulated patients with cerebral venous thrombosis?

    DEFF Research Database (Denmark)

    Feher, G; Illes, Z; Hargroves, D; Komoly, S

    2016-01-01

    INTRODUCTION: Cerebral venous thrombosis (CVT) is a rare form of venous thromboembolism (VTE). Although anticoagulation is recommended for the initial and long term treatment with regards to thrombotic risks for patients with CVT, the role of anticogalution has not been fully elucidated. The aim of...

  17. Treatment of Venous Thromboembolism With New Anticoagulant Agents.

    Science.gov (United States)

    Becattini, Cecilia; Agnelli, Giancarlo

    2016-04-26

    Venous thromboembolism (VTE) is a common disease associated with high risk for recurrences, death, and late sequelae, accounting for substantial health care costs. Anticoagulant agents are the mainstay of treatment for deep vein thrombosis and pulmonary embolism. The recent availability of oral anticoagulant agents that can be administered in fixed doses, without laboratory monitoring and dose adjustment, is a landmark change in the treatment of VTE. In Phase III trials, rivaroxaban, apixaban, edoxaban (antifactor Xa agents), and dabigatran (an antithrombin agent) were noninferior and probably safer than conventional anticoagulation therapy (low-molecular-weight heparin followed by vitamin K antagonists). These favorable results were confirmed in specific patient subgroups, such as the elderly and fragile. However, some patients, such as those with cancer or with intermediate- to high-risk pulmonary embolism, were underrepresented in the Phase III trials. Further clinical research is required before new oral anticoagulant agents can be considered standard of care for the full spectrum of patients with VTE. PMID:27102510

  18. Haemorrhage in the labyrinth caused by anticoagulant therapy: case report

    International Nuclear Information System (INIS)

    We report a patient who experienced a severe vertiginous episode with bilateral tinnitus and progressive right-sided hearing loss. She had Marfan's disease and was on anticoagulant treatment. The fluid in the labyrinth gave higher signal than cerebrospinal fluid on T1-weighted images, suggesting haemorrhage. The radiological follow-up is discussed. (orig.)

  19. Citrate Anticoagulation for CRRT in Children: Comparison with Heparin

    Directory of Open Access Journals (Sweden)

    Sara Nicole Fernández

    2014-01-01

    Full Text Available Regional anticoagulation with citrate is an alternative to heparin in continuous renal replacement therapies, which may prolong circuit lifetime and decrease hemorrhagic complications. A retrospective comparative cohort study based on a prospective observational registry was conducted including critically ill children undergoing CRRT. Efficacy, measured as circuit survival, and secondary effects of heparin and citrate were compared. 12 patients on CRRT with citrate anticoagulation and 24 patients with heparin anticoagulation were analyzed. Median citrate dose was 2.6 mmol/L. Median calcium dose was 0.16 mEq/kg/h. Median heparin dose was 15 UI/kg/h. Median circuit survival was 48 hours with citrate and 31 hours with heparin (P=0.028. 66.6% of patients treated with citrate developed mild metabolic alkalosis, which was directly related to citrate dose. There were no cases of citrate intoxication: median total calcium/ionic calcium index (CaT/I of 2.16 and a maximum CaT/I of 2.33, without metabolic acidosis. In the citrate group, 45.5% of patients developed hypochloremia and 27.3% hypomagnesemia. In the heparin group, 27.8% developed hypophosphatemia. Three patients were moved from heparin to citrate to control postoperatory bleeding. In conclusion citrate is a safe and effective anticoagulation method for CRRT in children and it achieves longer circuit survival than heparin.

  20. Citrate Anticoagulation for CRRT in Children: Comparison with Heparin

    Science.gov (United States)

    Fernández, Sara Nicole; Santiago, Maria José; López-Herce, Jesús; García, Miriam; Del Castillo, Jimena; Alcaraz, Andrés José; Bellón, Jose María

    2014-01-01

    Regional anticoagulation with citrate is an alternative to heparin in continuous renal replacement therapies, which may prolong circuit lifetime and decrease hemorrhagic complications. A retrospective comparative cohort study based on a prospective observational registry was conducted including critically ill children undergoing CRRT. Efficacy, measured as circuit survival, and secondary effects of heparin and citrate were compared. 12 patients on CRRT with citrate anticoagulation and 24 patients with heparin anticoagulation were analyzed. Median citrate dose was 2.6 mmol/L. Median calcium dose was 0.16 mEq/kg/h. Median heparin dose was 15 UI/kg/h. Median circuit survival was 48 hours with citrate and 31 hours with heparin (P = 0.028). 66.6% of patients treated with citrate developed mild metabolic alkalosis, which was directly related to citrate dose. There were no cases of citrate intoxication: median total calcium/ionic calcium index (CaT/I) of 2.16 and a maximum CaT/I of 2.33, without metabolic acidosis. In the citrate group, 45.5% of patients developed hypochloremia and 27.3% hypomagnesemia. In the heparin group, 27.8% developed hypophosphatemia. Three patients were moved from heparin to citrate to control postoperatory bleeding. In conclusion citrate is a safe and effective anticoagulation method for CRRT in children and it achieves longer circuit survival than heparin. PMID:25157369

  1. Vitamin K and stability of oral anticoagulant therapy

    NARCIS (Netherlands)

    Rombouts, Eva Karolien

    2011-01-01

    One of the causes of unstable anticoagulation is a variable vitamin K intake. The main objective of this thesis was to test the hypothesis that the INR is particularly sensitive to changes in vitamin K intake when vitamin K status is low, and that patients with a low vitamin K intake would therefore

  2. Haemorrhage in the labyrinth caused by anticoagulant therapy: case report

    Energy Technology Data Exchange (ETDEWEB)

    Callonnec, F.; Gerardin, E.; Thiebot, J. [Department of Radiology, Rouen University Hospital, 1 rue de Germont, F-76031 Rouen cedex (France); Marie, J.P.; Andrieu Guitrancourt, J. [Department of Otolaryngology, Rouen University Hospital (France); Marsot-Dupuch, K. [Department of Radiology, St. Antoine, Paris University Hospital (France)

    1999-06-01

    We report a patient who experienced a severe vertiginous episode with bilateral tinnitus and progressive right-sided hearing loss. She had Marfan`s disease and was on anticoagulant treatment. The fluid in the labyrinth gave higher signal than cerebrospinal fluid on T1-weighted images, suggesting haemorrhage. The radiological follow-up is discussed. (orig.) With 2 figs., 11 refs.

  3. Antiplatelet and anticoagulant therapy in elective percutaneous coronary intervention

    Directory of Open Access Journals (Sweden)

    Verheugt Freek WA

    2001-05-01

    Full Text Available Abstract Thrombosis plays a major role in acute vessel closure both after coronary balloon angioplasty and after stenting. This review will address the role of antiplatelet and anticoagulant therapy in preventing early thrombotic complications after percutaneous coronary intervention. The focus will be on agents that are routinely available and commonly used.

  4. Laboratory monitoring of novel oral anticoagulants rivaroxaban and dabigatran

    NARCIS (Netherlands)

    Eerenberg, E.S.; Kamphuisen, P.W.; Sijpkens, M.K.; Meijers, J.C.; Büller, H.R.; Levi, M.

    2013-01-01

    Background: Rivaroxaban and dabigatran are new oral anticoagulants that both have been licensed worldwide for the treatment of atrial fibrillation and rivaroxaban also for venous thrombosis. Both drugs specifically inhibit one coagulation factor, factor Xa and thrombin, respectively, and both compou

  5. Perioperative anticoagulation for children with prosthetic mechanical valves

    OpenAIRE

    Grech, Victor E.; Rees, P.

    2000-01-01

    The insertion of a mechanical heart valve predisposes to thrombosis and embolism, and for this reason, individuals with mechanical valves who undergo dental/surgical procedures must take special precautions. In this article, we illustrate a protocol for anticoagulation during such procedures in individuals with mechanical valves.

  6. Qualitative identification of rodenticide anticoagulants by LC-MS/MS.

    Science.gov (United States)

    Middleberg, Robert A; Homan, Joseph

    2012-01-01

    Rodenticide anticoagulants are used in the control of rodent populations. In addition to accidental ingestions in humans, such agents have also been used for homicidal and suicidal purposes. There are two major groups of rodenticide anticoagulants - hydroxycoumarins and indanediones. Before the advent of LC-MS/MS, analysis for such agents was relegated to such techniques as TLC and HPLC with nonspecific modes of detection. LC-MS/MS has been used to determine any given number of rodenticide anticoagulants in animal tissues, foods, plasma, etc. Use of this technique allows for the simultaneous identification of individual compounds within both classes of rodenticide anticoagulants. The LC-MS/MS method presented allows for simultaneous qualitative identification of brodifacoum, bromadiolone, chlorphacinone, dicumarol, difenacoum, diphacinone, and warfarin in blood, serum, and plasma using ESI in the negative mode. Two transitions are monitored for each analyte after a simple sample preparation. Chromatographic separation is accomplished using a gradient of ammonium hydroxide in water and ammonium hydroxide in methanol. Chloro-warfarin is used as internal standard. PMID:22767114

  7. Use of Oral Anticoagulation Therapy in Atrial Fibrillation after Stroke

    DEFF Research Database (Denmark)

    Jespersen, Stine Funder; Christensen, Louisa M; Christensen, Anders;

    2013-01-01

    Background. The knowledge is still sparse about patient related factors, influencing oral anticoagulation therapy (OAC) rates, in stroke patients with atrial fibrillation (AF). Aims. To assess the use of OAC in ischemic stroke patients diagnosed with AF and to identify patient related factors...

  8. Personalised treatment with oral anticoagulant drugs : clinical and economic issues

    NARCIS (Netherlands)

    Verhoef, T.I.

    2013-01-01

    Coumarin derivatives such as acenocoumarol, phenprocoumon and warfarin are frequently used for the prevention of stroke and systemic embolism in patients with atrial fibrillation or for the treatment of venous thromboembolism. These oral anticoagulants have a narrow therapeutic range and a large var

  9. Thoracic radiographic features of anticoagulant rodenticide toxicity in fourteen dogs

    International Nuclear Information System (INIS)

    Thoracic radiographs and clinical records from 14 dogs with confirmed anticoagulant rodenticide toxicity were reviewed. Twelve of the 14 dogs were presented with a chief complaint of respiratory distress, and 12 had elevated prothrombin and activated partial thromboplastin times consistent with a coagulopathy secondary to a clotting factor deficiency. Thoracic radiographs of the 14 dogs were reviewed and abnomalities included increased mediastinal soft tissue opacity with extra and intrathoracic tracheal narrowing (4/14), increased mediastinal soft tissue opacity without tracheal narrowing (8/14), variable degrees of pleural effusion (13/14) and generalized, patchy interstitial/alveolar pulmonary infiltrates (8/14). Radiographic evidence of cardiomegaly and pulmonary artery abnormalities consistent with concurrent heartworm infestation were detected in one dog. In four dogs, dramatic tracheal narrowing was identified on the lateral thoracic radiograph caused by either mediastinal hemorrhage compressing the trachea or submucosal hemorrhage within the tracheal lumen. The trachea was displaced in a ventral direction in two dogs, and extra and intrathoracic luminal diameter narrowing was evident cranially in all four dogs. Two of these four dogs had soft tissue opacity within the dorsal trachea that extended from the larynx to the intrathoracic trachea. Twelve of the 14 dogs survived with standard treatment protocols utilizing injectable and oral vitamin K1. One dog died from pancreatitis and disseminated intravascular coagulopathy. The other dog died soon after presentation due to severe, disseminated hemorrhage. Follow-up thoracic radiographs were made in four dogs that survived and showed resolution of the mediastinal, pleural and pulmonary changes within one to five days after the initiation of vitamin K1 therapy

  10. Novel Antiplatelet Activity of Minocycline Involves Inhibition of MLK3-p38 Mitogen Activated Protein Kinase Axis.

    Directory of Open Access Journals (Sweden)

    Joseph W Jackson

    Full Text Available Platelets play an essential role in hemostasis and wound healing by facilitating thrombus formation at sites of injury. Platelets also mediate inflammation and contain several pro-inflammatory molecules including cytokines and chemokines that mediate leukocyte recruitment and activation. Not surprisingly, platelet dysfunction is known to contribute to several inflammatory disorders. Antiplatelet therapies, such as aspirin, adenosine diphosphate (ADP antagonists, glycoprotein IIb/IIIa (GPIIb/IIIa inhibitors, and anticoagulants such as warfarin, dampen platelet activity at the risk of unwarranted bleeding. Thus, the development of drugs that reduce platelet-mediated inflammation without interfering with thrombus formation is of importance to combat platelet-associated disorders. We have shown here for the first time that the tetracycline antibiotic, minocycline, administered to HIV-infected individuals reduces plasma levels of soluble CD40L and platelet factor 4 levels, host molecules predominately released by platelets. Minocycline reduced the activation of isolated platelets in the presence of the potent platelet activator, thrombin, as measured by ELISA and flow cytometry. Platelet degranulation was reduced upon exposure to minocycline as shown by mepacrine retention and flow cytometry. However, minocycline had no effect on spreading, aggregation, GPIIb/IIIa activation, or in vivo thrombus formation. Lastly, immunoblot analysis suggests that the antiplatelet activity of minocycline is likely mediated by inhibition of mixed lineage kinase 3 (MLK3-p38 MAPK signaling axis and loss of p38 activity. Our findings provide a better understanding of platelet biology and a novel repurposing of an established antibiotic, minocycline, to specifically reduce platelet granule release without affecting thrombosis, which may yield insights in generating novel, specific antiplatelet therapies.

  11. Novel Antiplatelet Activity of Minocycline Involves Inhibition of MLK3-p38 Mitogen Activated Protein Kinase Axis

    Science.gov (United States)

    Jackson, Joseph W.; Singh, Meera V.; Singh, Vir B.; Jones, Letitia D.; Davidson, Gregory A.; Ture, Sara; Morrell, Craig N.; Schifitto, Giovanni; Maggirwar, Sanjay B.

    2016-01-01

    Platelets play an essential role in hemostasis and wound healing by facilitating thrombus formation at sites of injury. Platelets also mediate inflammation and contain several pro-inflammatory molecules including cytokines and chemokines that mediate leukocyte recruitment and activation. Not surprisingly, platelet dysfunction is known to contribute to several inflammatory disorders. Antiplatelet therapies, such as aspirin, adenosine diphosphate (ADP) antagonists, glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors, and anticoagulants such as warfarin, dampen platelet activity at the risk of unwarranted bleeding. Thus, the development of drugs that reduce platelet-mediated inflammation without interfering with thrombus formation is of importance to combat platelet-associated disorders. We have shown here for the first time that the tetracycline antibiotic, minocycline, administered to HIV-infected individuals reduces plasma levels of soluble CD40L and platelet factor 4 levels, host molecules predominately released by platelets. Minocycline reduced the activation of isolated platelets in the presence of the potent platelet activator, thrombin, as measured by ELISA and flow cytometry. Platelet degranulation was reduced upon exposure to minocycline as shown by mepacrine retention and flow cytometry. However, minocycline had no effect on spreading, aggregation, GPIIb/IIIa activation, or in vivo thrombus formation. Lastly, immunoblot analysis suggests that the antiplatelet activity of minocycline is likely mediated by inhibition of mixed lineage kinase 3 (MLK3)-p38 MAPK signaling axis and loss of p38 activity. Our findings provide a better understanding of platelet biology and a novel repurposing of an established antibiotic, minocycline, to specifically reduce platelet granule release without affecting thrombosis, which may yield insights in generating novel, specific antiplatelet therapies. PMID:27270236

  12. Leishmania amazonensis: PKC-like protein kinase modulates the (Na++K+)ATPase activity.

    Science.gov (United States)

    Almeida-Amaral, Elmo Eduardo de; Caruso-Neves, Celso; Lara, Lucienne Silva; Pinheiro, Carla Mônica; Meyer-Fernandes, José Roberto

    2007-08-01

    The present study aimed to identify the presence of protein kinase C-like (PKC-like) in Leishmania amazonensis and to elucidate its possible role in the modulation of the (Na(+)+K(+))ATPase activity. Immunoblotting experiments using antibody against a consensus sequence (Ac 543-549) of rabbit protein kinase C (PKC) revealed the presence of a protein kinase of 80 kDa in L. amazonensis. Measurements of protein kinase activity showed the presence of both (Ca(2+)-dependent) and (Ca(2+)-independent) protein kinase activity in plasma membrane and cytosol. Phorbol ester (PMA) activation of the Ca(2+)-dependent protein kinase stimulated the (Na(+)+K(+))ATPase activity, while activation of the Ca(2+)-independent protein kinase was inhibitory. Both effects of protein kinase on the (Na(+)+K(+))ATPase of the plasma membrane were lower than that observed in intact cells. PMA induced the translocation of protein kinase from cytosol to plasma membrane, indicating that the maximal effect of protein kinase on the (Na(+)+K(+))ATPase activity depends on the synergistic action of protein kinases from both plasma membrane and cytosol. This is the first demonstration of a protein kinase activated by PMA in L. amazonensis and the first evidence for a possible role in the regulation of the (Na(+)+K(+))ATPase activity in this trypanosomatid. Modulation of the (Na(+)+K(+))ATPase by protein kinase in a trypanosomatid opens up new possibilities to understand the regulation of ion homeostasis in this parasite. PMID:17475255

  13. PPAR-β/δ activation promotes phospholipid transfer protein expression.

    Science.gov (United States)

    Chehaibi, Khouloud; Cedó, Lídia; Metso, Jari; Palomer, Xavier; Santos, David; Quesada, Helena; Naceur Slimane, Mohamed; Wahli, Walter; Julve, Josep; Vázquez-Carrera, Manuel; Jauhiainen, Matti; Blanco-Vaca, Francisco; Escolà-Gil, Joan Carles

    2015-03-15

    The peroxisome proliferator-activated receptor (PPAR)-β/δ has emerged as a promising therapeutic target for treating dyslipidemia, including beneficial effects on HDL cholesterol (HDL-C). In the current study, we determined the effects of the PPAR-β/δ agonist GW0742 on HDL composition and the expression of liver HDL-related genes in mice and cultured human cells. The experiments were carried out in C57BL/6 wild-type, LDL receptor (LDLR)-deficient mice and PPAR-β/δ-deficient mice treated with GW0742 (10mg/kg/day) or a vehicle solution for 14 days. GW0742 upregulated liver phospholipid transfer protein (Pltp) gene expression and increased serum PLTP activity in mice. When given to wild-type mice, GW0742 significantly increased serum HDL-C and HDL phospholipids; GW0742 also raised serum potential to generate preβ-HDL formation. The GW0742-mediated effects on liver Pltp expression and serum enzyme activity were completely abolished in PPAR-β/δ-deficient mice. GW0742 also stimulated PLTP mRNA expression in mouse J774 macrophages, differentiated human THP-1 macrophages and human hepatoma Huh7. Collectively, our findings demonstrate a common transcriptional upregulation by GW0742-activated PPAR-β/δ of Pltp expression in cultured cells and in mouse liver resulting in enhanced serum PLTP activity. Our results also indicate that PPAR-β/δ activation may modulate PLTP-mediated preβ-HDL formation and macrophage cholesterol efflux. PMID:25662586

  14. Protein kinase A binds and activates heat shock factor 1.

    Directory of Open Access Journals (Sweden)

    Ayesha Murshid

    Full Text Available BACKGROUND: Many inducible transcription factors are regulated through batteries of posttranslational modifications that couple their activity to inducing stimuli. We have studied such regulation of Heat Shock Factor 1 (HSF1, a key protein in control of the heat shock response, and a participant in carcinogenisis, neurological health and aging. As the mechanisms involved in the intracellular regulation of HSF1 in good health and its dysregulation in disease are still incomplete we are investigating the role of posttranslational modifications in such regulation. METHODOLOGY/PRINCIPAL FINDINGS: In a proteomic study of HSF1 binding partners, we have discovered its association with the pleiotropic protein kinase A (PKA. HSF1 binds avidly to the catalytic subunit of PKA, (PKAcα and becomes phosphorylated on a novel serine phosphorylation site within its central regulatory domain (serine 320 or S320, both in vitro and in vivo. Intracellular PKAcα levels and phosphorylation of HSF1 at S320 were both required for HSF1 to be localized to the nucleus, bind to response elements in the promoter of an HSF1 target gene (hsp70.1 and activate hsp70.1 after stress. Reduction in PKAcα levels by small hairpin RNA led to HSF1 exclusion from the nucleus, its exodus from the hsp70.1 promoter and decreased hsp70.1 transcription. Likewise, null mutation of HSF1 at S320 by alanine substitution for serine led to an HSF1 species excluded from the nucleus and deficient in hsp70.1 activation. CONCLUSIONS: These findings of PKA regulation of HSF1 through S320 phosphorylation add to our knowledge of the signaling networks converging on this factor and may contribute to elucidating its complex roles in the stress response and understanding HSF1 dysregulation in disease.

  15. Sustained mitogen-activated protein kinase activation reprograms defense metabolism and phosphoprotein profile in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Ines eLassowskat

    2014-10-01

    Full Text Available Mitogen-activated protein kinases (MAPKs target a variety of protein substrates to regulate cellular signaling processes in eukaryotes. In plants, the number of identified MAPK substrates that control plant defense responses is still limited. Here, we generated transgenic Arabidopsis thaliana plants with an inducible system to simulate in vivo activation of two stress-activated MAPKs, MPK3 and MPK6. Metabolome analysis revealed that this artificial MPK3/6 activation (without any exposure to pathogens or other stresses is sufficient to drive the production of major defense-related metabolites, including various camalexin, indole glucosinolate and agmatine derivatives. An accompanying (phosphoproteome analysis led to detection of hundreds of potential phosphoproteins downstream of MPK3/6 activation. Besides known MAPK substrates, many candidates on this list possess typical MAPK-targeted phosphosites and in many cases, the corresponding phosphopeptides were detected by mass spectrometry. Notably, several of these putative phosphoproteins have been reported to be associated with the biosynthesis of antimicrobial defense substances (e.g. WRKY transcription factors and proteins encoded by the genes from the PEN pathway required for penetration resistance to filamentous pathogens. Thus, this work provides an inventory of candidate phosphoproteins, including putative direct MAPK substrates, for future analysis of MAPK-mediated defense control. (Proteomics data are available with the identifier PXD001252 via ProteomeXchange, http://proteomecentral.proteomexchange.org.

  16. Danthron activates AMP-activated protein kinase and regulates lipid and glucose metabolism in vitro

    Institute of Scientific and Technical Information of China (English)

    Rong ZHOU; Ling WANG; Xing XU; Jing CHEN; Li-hong HU; Li-li CHEN; Xu SHEN

    2013-01-01

    Aim:To discover the active compound on AMP-activated protein kinase (AMPK) activation and investigate the effects of the active compound 1,8-dihydroxyanthraquinone (danthron) from the traditional Chinese medicine rhubarb on AMPK-mediated lipid and glucose metabolism in vitro.Methods:HepG2 and C2C12 cells were used.Cell viability was determined using MTT assay.Real-time PCR was performed to measure the gene expression.Western blotting assay was applied to investigate the protein phosphorylation level.Enzymatic assay kits were used to detect the total cholesterol (TC),triglyceride (TG) and glucose contents.Results:Danthron (0.1,1,and 10 μmol/L) dose-dependently promoted the phosphorylation of AMPK and acetyl-CoA carboxylase (ACC)in both HepG2 and C2C12 cells.Meanwhile,danthron treatment significantly reduced the lipid synthesis related sterol regulatory element-binding protein 1c (SREBP1c) and fatty acid synthetase (FAS) gene expressions,and the TC and TG levels.In addition,danthron treatment efficiently increased glucose consumption.The actions of danthron on lipid and glucose metabolism were abolished or reversed by co-treatment with the AMPK inhibitor compound C.Conclusion:Danthron effectively reduces intracellular lipid contents and enhanced glucose consumption in vitro via activation of AMPK signaling pathway.

  17. AMP-activated protein kinase (AMPK) activation regulates in vitro bone formation and bone mass

    OpenAIRE

    Shah, M; Kola, B; Bataveljic, A.; Arnett, T. R.; Viollet, B.; Saxon, L.; Korbonits, M.; C. Chenu

    2010-01-01

    Adenosine 5′-monophosphate-activated protein kinase (AMPK), a regulator of energy homeostasis, has a central role in mediating the appetite-modulating and metabolic effects of many hormones and antidiabetic drugs metformin and glitazones. The objective of this study was to determine if AMPK can be activated in osteoblasts by known AMPK modulators and if AMPK activity is involved in osteoblast function in vitro and regulation of bone mass in vivo. ROS 17/2.8 rat osteoblast-like cells were cult...

  18. FUNCTION OF THE ACTIVATED PROTEIN C (APC) AUTOLYSIS LOOP IN ACTIVATED FVIII INACTIVATION

    OpenAIRE

    Cramer, Thomas J.; Gale, Andrew J.

    2011-01-01

    Activated protein C (APC) binds to its substrates activated factor V (FVa) and activated factor VIII (FVIIIa) with a basic exosite that consists of loops 37, 60, 70 and the autolysis loop. These loops have a high density of basic residues, resulting in a positive charge on the surface of APC. Many of these residues are important in the interaction of APC with FVa and FVIIIa. The current study focused on the function of the autolysis loop in the interaction with FVIIIa. This loop was previousl...

  19. The RecX protein interacts with the RecA protein and modulates its activity in Herbaspirillum seropedicae

    International Nuclear Information System (INIS)

    DNA repair is crucial to the survival of all organisms. The bacterial RecA protein is a central component in the SOS response and in recombinational and SOS DNA repairs. The RecX protein has been characterized as a negative modulator of RecA activity in many bacteria. The recA and recX genes of Herbaspirillum seropedicae constitute a single operon, and evidence suggests that RecX participates in SOS repair. In the present study, we show that the H. seropedicae RecX protein (RecXHs) can interact with the H. seropedicae RecA protein (RecAHs) and that RecAHs possesses ATP binding, ATP hydrolyzing and DNA strand exchange activities. RecXHs inhibited 90% of the RecAHs DNA strand exchange activity even when present in a 50-fold lower molar concentration than RecAHs. RecAHs ATP binding was not affected by the addition of RecX, but the ATPase activity was reduced. When RecXHs was present before the formation of RecA filaments (RecA-ssDNA), inhibition of ATPase activity was substantially reduced and excess ssDNA also partially suppressed this inhibition. The results suggest that the RecXHs protein negatively modulates the RecAHs activities by protein-protein interactions and also by DNA-protein interactions

  20. The RecX protein interacts with the RecA protein and modulates its activity in Herbaspirillum seropedicae

    Directory of Open Access Journals (Sweden)

    C.W. Galvão

    2012-12-01

    Full Text Available DNA repair is crucial to the survival of all organisms. The bacterial RecA protein is a central component in the SOS response and in recombinational and SOS DNA repairs. The RecX protein has been characterized as a negative modulator of RecA activity in many bacteria. The recA and recX genes of Herbaspirillum seropedicae constitute a single operon, and evidence suggests that RecX participates in SOS repair. In the present study, we show that the H. seropedicae RecX protein (RecX Hs can interact with the H. seropedicaeRecA protein (RecA Hs and that RecA Hs possesses ATP binding, ATP hydrolyzing and DNA strand exchange activities. RecX Hs inhibited 90% of the RecA Hs DNA strand exchange activity even when present in a 50-fold lower molar concentration than RecA Hs. RecA Hs ATP binding was not affected by the addition of RecX, but the ATPase activity was reduced. When RecX Hs was present before the formation of RecA filaments (RecA-ssDNA, inhibition of ATPase activity was substantially reduced and excess ssDNA also partially suppressed this inhibition. The results suggest that the RecX Hs protein negatively modulates the RecA Hs activities by protein-protein interactions and also by DNA-protein interactions.

  1. The RecX protein interacts with the RecA protein and modulates its activity in Herbaspirillum seropedicae

    Energy Technology Data Exchange (ETDEWEB)

    Galvão, C.W. [Departamento de Biologia Estrutural, Molecular e Genética, Universidade Estadual de Ponta Grossa, Ponta Grossa, PR (Brazil); Souza, E.M. [Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR (Brazil); Etto, R.M. [Departamento de Biologia Estrutural, Molecular e Genética, Universidade Estadual de Ponta Grossa, Ponta Grossa, PR (Brazil); Pedrosa, F.O.; Chubatsu, L.S.; Yates, M.G. [Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR (Brazil); Schumacher, J.; Buck, M. [Department of Life Sciences, Imperial College London, London (United Kingdom); Steffens, M.B.R. [Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, PR (Brazil)

    2012-10-15

    DNA repair is crucial to the survival of all organisms. The bacterial RecA protein is a central component in the SOS response and in recombinational and SOS DNA repairs. The RecX protein has been characterized as a negative modulator of RecA activity in many bacteria. The recA and recX genes of Herbaspirillum seropedicae constitute a single operon, and evidence suggests that RecX participates in SOS repair. In the present study, we show that the H. seropedicae RecX protein (RecX{sub Hs}) can interact with the H. seropedicae RecA protein (RecA{sub Hs}) and that RecA{sub Hs} possesses ATP binding, ATP hydrolyzing and DNA strand exchange activities. RecX{sub Hs} inhibited 90% of the RecA{sub Hs} DNA strand exchange activity even when present in a 50-fold lower molar concentration than RecA{sub Hs}. RecA{sub Hs} ATP binding was not affected by the addition of RecX, but the ATPase activity was reduced. When RecX{sub Hs} was present before the formation of RecA filaments (RecA-ssDNA), inhibition of ATPase activity was substantially reduced and excess ssDNA also partially suppressed this inhibition. The results suggest that the RecX{sub Hs} protein negatively modulates the RecA{sub Hs} activities by protein-protein interactions and also by DNA-protein interactions.

  2. Myristylation alters DNA-binding activity and transactivation of FBR (gag-fos) protein.

    OpenAIRE

    Kamata, N; Jotte, R M; Holt, J. T.

    1991-01-01

    FBR murine sarcoma virus (gag-fos) protein, a virally transduced Fos protein, exhibits decreased gene transactivation in comparison with the cellular Fos protein. Biochemical analysis suggests that myristylation of the virally encoded N-terminal gag region results in decreased DNA binding and transcriptional activation without affecting heterodimerization with Jun protein. These findings demonstrate that protein myristylation can modulate gene regulation by a DNA-binding protein.

  3. Characteristics of ambulatory anticoagulant adverse drug events: a descriptive study

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    Eckstrand Julie

    2010-02-01

    Full Text Available Abstract Background Despite the high frequency with which adverse drug events (ADEs occur in outpatient settings, detailed information regarding these events remains limited. Anticoagulant drugs are associated with increased safety concerns and are commonly involved in outpatient ADEs. We therefore sought to evaluate ambulatory anticoagulation ADEs and the patient population in which they occurred within the Duke University Health System (Durham, NC, USA. Methods A retrospective chart review of ambulatory warfarin-related ADEs was conducted. An automated trigger surveillance system identified eligible events in ambulatory patients admitted with an International Normalized Ratio (INR >3 and administration of vitamin K. Event and patient characteristics were evaluated, and quality/process improvement strategies for ambulatory anticoagulation management are described. Results A total of 169 events in 167 patients were identified from December 1, 2006-June 30, 2008 and included in the study. A median supratherapeutic INR of 6.1 was noted, and roughly half of all events (52.1% were associated with a bleed. Nearly 74% of events resulted in a need for fresh frozen plasma; 64.8% of bleeds were classified as major. A total of 59.2% of events were at least partially responsible for hospital admission. Median patient age was 68 y (range 36-95 y with 24.9% initiating therapy within 3 months prior to the event. Of events with a prior documented patient visit (n = 157, 73.2% were seen at a Duke clinic or hospital within the previous month. Almost 80% of these patients had anticoagulation therapy addressed, but only 60.0% had a follow-up plan documented in the electronic note. Conclusions Ambulatory warfarin-related ADEs have significant patient and healthcare utilization consequences in the form of bleeding events and associated hospital admissions. Recommendations for improvement in anticoagulation management include use of information technology to assist

  4. Modeling intracerebral hemorrhage growth and response to anticoagulation.

    Directory of Open Access Journals (Sweden)

    Charles H Greenberg

    Full Text Available The mechanism for hemorrhage enlargement in the brain, a key determinant of patient outcome following hemorrhagic stroke, is unknown. We performed computer-based stochastic simulation of one proposed mechanism, in which hemorrhages grow in "domino" fashion via secondary shearing of neighboring vessel segments. Hemorrhages were simulated by creating an initial site of primary bleeding and an associated risk of secondary rupture at adjacent sites that decayed over time. Under particular combinations of parameters for likelihood of secondary rupture and time-dependent decay, a subset of lesions expanded, creating a bimodal distribution of microbleeds and macrobleeds. Systematic variation of the model to simulate anticoagulation yielded increases in both macrobleed occurrence (26.9%, 53.2%, and 70.0% of all hemorrhagic events under conditions simulating no, low-level, and high-level anticoagulation and final hemorrhage size (median volumes 111, 276, and 412 under the same three conditions, consistent with data from patients with anticoagulant-related brain hemorrhages. Reversal from simulated high-level anticoagulation to normal coagulation was able to reduce final hemorrhage size only if applied relatively early in the course of hemorrhage expansion. These findings suggest that a model based on a secondary shearing mechanism can account for some of the clinically observed properties of intracerebral hemorrhage, including the bimodal distribution of volumes and the enhanced hemorrhage growth seen with anticoagulation. Future iterations of this model may be useful for elucidating the effects of hemorrhage growth of factors related to secondary shearing (such as small vessel pathology or time-dependent decay (such as hemostatic agents.

  5. Worldwide management of oral anticoagulant therapy: the ISAM study.

    Science.gov (United States)

    Pengo, Vittorio; Pegoraro, Cinzia; Cucchini, Umberto; Iliceto, Sabino

    2006-02-01

    A multicenter, observational, retrospective, cross-sectional study of patients, receiving oral anticoagulation therapy (OAT) for stroke prophylaxis in chronic non-valvular atrial fibrillation (NVAF) was conducted in the US, Canada, France, Italy and Spain according to their predominant model of care [routine medical care (RMC) or Anticoagulation Clinic care (ACC)]. The study objectives were to assess anticoagulation control (time in target range), and to describe the features of the local model of care. Consecutive patients were recruited on the basis of a minimum of 60 days of oral anticoagulant treatment over a 12 month period, and clinic and physician details were captured by means of a structured face-to-face or telephone interview. Time in therapeutic range (TTR) was calculated by using linear interpolation between INR values. A total of 1511 patients were recruited, of whom 1445 were included in the analysis of TTR. TTR was higher in ACC (69.5% and 64.9% for Italy and Spain, respectively) with respect to RMC (58.1%, 62.8% and 59.3% for the US, Canada and France, respectively). Mean intervals between INR determinations were between 3 and 4 weeks. Dose changes in case of INR outside therapeutic range were more frequent in Spain and less frequent in France. Striking differences were observed in type of VKA used, specialists involved in patient management, and dosage instructions. Studying of anticoagulation management based on local models of care highlights important discrepancies among countries and suggests further standardization of the management of this important therapy is necessary. PMID:16475046

  6. Exploring the active site structure of photoreceptor proteins by Raman optical activity

    Science.gov (United States)

    Unno, Masashi

    2015-03-01

    Understanding protein function at the atomic level is a major challenge in a field of biophysics and requires the combined efforts of structural and functional methods. We use photoreceptor proteins as a model system to understand in atomic detail how a chromophore and a protein interact to sense light and send a biological signal. A potential technique for investigating molecular structures is Raman optical activity (ROA), which is a spectroscopic method with a high sensitivity to the structural details of chiral molecules. However, its application to photoreceptor proteins has not been reported. Thus we have constructed ROA spectrometer using near-infrared (NIR) laser excitation at 785 nm. The NIR excitation enables us to measure ROA spectra for a variety of biological samples, including photoreceptor proteins, without fluorescence from the samples. In the present study, we have applied the NIR-ROA to bacteriorhodopsin (BR) and photoactive yellow protein (PYP). BR is a light-driven proton pump and contains a protonated Schiff base of retinal as a chromophore. PYP is a blue light receptor, and this protein has the 4-hydroxycinnamyl chromophore, which is covalently linked to Cys69 through a thiolester bond. We have successfully obtained the ROA spectra of the chromophore within a protein environment. Furthermore, calculations of the ROA spectra utilizing density functional theory provide detailed structural information, such as data on out-of-plane distortions of the chromophore. The structural information obtained from the ROA spectra includes the positions of hydrogen atoms, which are usually not detected in the crystal structures of biological samples.

  7. Protective effects of activated protein C on neurovascular unit in a rat model of intrauterine infection-induced neonatal white matter injury.

    Science.gov (United States)

    Jin, Sheng-juan; Liu, Yan; Deng, Shi-hua; Lin, Tu-lian; Rashid, Abid; Liao, Li-hong; Ning, Qin; Luo, Xiao-ping

    2015-12-01

    Activated protein C (APC), a natural anticoagulant, has been reported to exert direct vasculoprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. This study was aimed to explore the neuroprotective effects and potential mechanisms of APC on the neurovascular unit of neonatal rats with intrauterine infection-induced white matter injury. Intraperitoneal injection of 300 μg/kg lipopolysaccharide (LPS) was administered consecutively to pregnant Sprague-Dawley rats at embryonic days 19 and 20 to establish the rat model of intrauterine infection- induced white matter injury. Control rats were injected with an equivalent amount of sterile saline on the same time. APC at the dosage of 0.2 mg/kg was intraperitoneally injected to neonatal rats immediately after birth. Brain tissues were collected at postnatal day 7 and stained with hematoxylin and eosin (H&E). Immunohistochemistry was used to evaluate myelin basic protein (MBP) expression in the periventricular white matter region. Blood-brain barrier (BBB) permeability and brain water content were measured using Evens Blue dye and wet/dry weight method. Double immunofluorescence staining and real-time quantitative PCR were performed to detect microglial activation and the expression of protease activated receptor 1 (PAR1). Typical pathological changes of white matter injury were observed in rat brains exposed to LPS, and MBP expression in the periventricular region was significantly decreased. BBB was disrupted and the brain water content was increased. Microglia were largely activated and the mRNA and protein levels of PAR1 were elevated. APC administration ameliorated the pathological lesions of the white matter and increased MBP expression. BBB permeability and brain water content were reduced. Microglia activation was inhibited and the PAR1 mRNA and protein expression levels were both down-regulated. Our results suggested that APC exerted neuroprotective effects

  8. Stimulation of IGF-binding protein-1 secretion by AMP-activated protein kinase.

    Science.gov (United States)

    Lewitt, M S

    2001-04-20

    Insulin-like growth factor-binding protein-1 (IGFBP-1) is stimulated during intensive exercise and in catabolic conditions to very high concentrations, which are not completely explained by known regulators such as insulin and glucocorticoids. The role of AMP-activated protein kinase (AMPK), an important signaling system in lipid and carbohydrate metabolism, in regulating IGFBP-1 was studied in H4-II-E rat hepatoma cells. Arsenic(III) oxide and 5-aminoimidazole-4-carboxamide-riboside (AICAR) were used as activators. AICAR (150 microM) stimulated IGFBP-1 secretion twofold during a 5-h incubation (P = 0.002). Insulin (100 ng/ml) inhibited IGFBP-1 by 80% (P < 0.001), but this was completely abolished in the presence of 150 microM AICAR. The effect of dexamethasone in stimulating IGFBP-1 threefold was additive to the effect of AICAR (P < 0.001) and, in the presence of AICAR, was incompletely inhibited by insulin. In conclusion AMPK is identified as a novel regulatory pathway for IGFBP-1, stimulating secretion and blocking the inhibitory effect of insulin. PMID:11302732

  9. Mitogen-activated protein kinase activator with WD40 repeats (MAWD) and MAWD-binding protein induce cell differentiation in gastric cancer

    OpenAIRE

    Li, Dongmei; Zhang, Jun; Xi, Yu; Zhang, Lei; Li, Wenmei; Cui, Jiantao; Xing, Rui; Pan, Yuanmin; Pan, Zemin; Li, Feng; Lu, Youyong

    2015-01-01

    Background Our previous proteomic analysis revealed that mitogen-activated protein kinase activator with WD40 repeats (MAWD) and MAWD-binding protein (MAWBP) were downregulated in gastric cancer (GC) tissues. These proteins interacted and formed complexes in GC cells. To investigate the role of MAWD and MAWBP in GC differentiation, we analyzed the relationship between MAWD/MAWBP and clinicopathologic characteristics of GC tissues and examined the expression of E-cadherin and pepsinogen C (PGC...

  10. Cordycepin activates AMP-activated protein kinase (AMPK) via interaction with the γ1 subunit

    Science.gov (United States)

    Wu, Chongming; Guo, Yanshen; Su, Yan; Zhang, Xue; Luan, Hong; Zhang, Xiaopo; Zhu, Huixin; He, Huixia; Wang, Xiaoliang; Sun, Guibo; Sun, Xiaobo; Guo, Peng; Zhu, Ping

    2014-01-01

    Cordycepin is a bioactive component of the fungus Cordyceps militaris. Previously, we showed that cordycepin can alleviate hyperlipidemia through enhancing the phosphorylation of AMP-activated protein kinase (AMPK), but the mechanism of this stimulation is unknown. Here, we investigated the potential mechanisms of cordycepin-induced AMPK activation in HepG2 cells. Treatment with cordycepin largely reduced oleic acid (OA)-elicited intracellular lipid accumulation and increased AMPK activity in a dose-dependent manner. Cordycepin-induced AMPK activation was not accompanied by changes in either the intracellular levels of AMP or the AMP/ATP ratio, nor was it influenced by calmodulin-dependent protein kinase kinase (CaMKK) inhibition; however, this activation was significantly suppressed by liver kinase B1 (LKB1) knockdown. Molecular docking, fluorescent and circular dichroism measurements showed that cordycepin interacted with the γ1 subunit of AMPK. Knockdown of AMPKγ1 by siRNA substantially abolished the effects of cordycepin on AMPK activation and lipid regulation. The modulating effects of cordycepin on the mRNA levels of key lipid regulatory genes were also largely reversed when AMPKγ1 expression was inhibited. Together, these data suggest that cordycepin may inhibit intracellular lipid accumulation through activation of AMPK via interaction with the γ1 subunit. PMID:24286368

  11. Influence of the sample anticoagulant on the measurements of impedance aggregometry in cardiac surgery

    Directory of Open Access Journals (Sweden)

    Cristina Solomon

    2008-10-01

    Full Text Available Cristina Solomon1, Michael Winterhalter1, Isabel Gilde1, Ludwig Hoy2, Andreas Calatzis3, Niels Rahe-Meyer11Department of Anesthesiology, Hannover Medical School, Hannover, Germany; 2Institute for Biometry, Hannover Medical School, Hannover, Germany; 3Department Hemostasis Transfusion Medicine, University Hospital Munich, Munich, GermanyBackground: The standard method of assessment of platelet function is represented by light transmission aggregometry (LTA, performed in citrated platelet-rich plasma (PRP. With LTA, decrease and subsequent post-cardiopulmonary bypass (CPB recovery of platelet function have been reported during cardiac surgery. Multiple electrode aggregometry (MEA may be used as point-of-care method to monitor perioperative changes in platelet function. Since MEA assesses macroaggregation which is influenced by the plasmatic levels of unbound calcium, citrate may be inadequate as anticoagulant for MEA. We used citrate and heparin for MEA samples, to see with which anticoagulant the intraoperative decrease and postoperative recovery in platelet function previously described with other aggregometric methods in cardiac surgery may be observed with MEA.Methods: Blood was obtained from 60 patients undergoing routine cardiac surgery and the samples were collected in standard tubes containing unfractionated heparin (50 U/mL or trisodium citrate (3.2%. The samples were obtained before CPB, at 30 minutes on CPB, end of CPB and on the first postoperative day. MEA was performed using the Multiplate® analyzer. Collagen (COLtest, 100 μg/mL and TRAP-6 (thrombin receptor activating peptide, TRAPtest, 1mM/mL were used as aggregation agonists.Results: Platelet aggregometric response decreased significantly during CPB. Platelet aggregation assessed using TRAP-6 as agonist on heparinized blood significantly correlated with the duration of CPB (r = −0.41, p = 0.001, 2-tailed Pearson test. The aggregometric analysis performed on the first

  12. Activation of purified calcium channels by stoichiometric protein phosphorylation

    International Nuclear Information System (INIS)

    Purified dihydropyridine-sensitive calcium channels from rabbit skeletal muscle were reconstituted into phosphatidylcholine vesicles to evaluate the effect of phosphorylation by cyclic AMP-dependent protein kinase (PK-A) on their function. Both the rate and extent of 45Ca2+ uptake into vesicles containing reconstituted calcium channels were increased severalfold after incubation with ATP and PK-A. The degree of stimulation of 45Ca2+ uptake was linearly proportional to the extent of phosphorylation of the alpha 1 and beta subunits of the calcium channel up to a stoichiometry of approximately 1 mol of phosphate incorporated into each subunit. The calcium channels activated by phosphorylation were determined to be incorporated into the reconstituted vesicles in the inside-out orientation and were completely inhibited by low concentrations of dihydropyridines, phenylalkylamines, Cd2+, Ni2+, and Mg2+. The results demonstrate a direct relationship between PK-A-catalyzed phosphorylation of the alpha 1 and beta subunits of the purified calcium channel and activation of the ion conductance activity of the dihydropyridine-sensitive calcium channels

  13. Cyclic nucleotides and mitogen-activated protein kinases: regulation of simvastatin in platelet activation

    Directory of Open Access Journals (Sweden)

    Hou Ssu-Yu

    2010-06-01

    Full Text Available Abstract Background 3-Hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA reductase inhibitors (statins have been widely used to reduce cardiovascular risk. These statins (i.e., simvastatin may exert other effects besides from their cholesterol-lowering actions, including inhibition of platelet activation. Platelet activation is relevant to a variety of coronary heart diseases. Although the inhibitory effect of simvastatin in platelet activation has been studied; the detailed signal transductions by which simvastatin inhibit platelet activation has not yet been completely resolved. Methods The aim of this study was to systematically examine the detailed mechanisms of simvastatin in preventing platelet activation. Platelet aggregation, flow cytometric analysis, immunoblotting, and electron spin resonance studies were used to assess the antiplatelet activity of simvastatin. Results Simvastatin (20-50 μM exhibited more-potent activity of inhibiting platelet aggregation stimulated by collagen than other agonists (i.e., thrombin. Simvastatin inhibited collagen-stimulated platelet activation accompanied by [Ca2+]i mobilization, thromboxane A2 (TxA2 formation, and phospholipase C (PLCγ2, protein kinase C (PKC, and mitogen-activated protein kinases (i.e., p38 MAPK, JNKs phosphorylation in washed platelets. Simvastatin obviously increased both cyclic AMP and cyclic GMP levels. Simvastatin markedly increased NO release, vasodilator-stimulated phosphoprotein (VASP phosphorylation, and endothelial nitric oxide synthase (eNOS expression. SQ22536, an inhibitor of adenylate cyclase, markedly reversed the simvastatin-mediated inhibitory effects on platelet aggregation, PLCγ2 and p38 MAPK phosphorylation, and simvastatin-mediated stimulatory effects on VASP and eNOS phosphorylation. Conclusion The most important findings of this study demonstrate for the first time that inhibitory effect of simvastatin in platelet activation may involve activation of the cyclic AMP

  14. Polissacarídeos sulfatados isolados das clorofíceas Caulerpa racemosa e Caulerpa cupressoides – extração, fracionamento e atividade anticoagulante - doi: 10.4025/actascibiolsci.v32i2.5923 Sulfated polysaccharides isolated from Caulerpa racemosa and Caulerpa cupressoides (Chlorophyceaes – extraction, fractionation and anticoagulant activity - doi: 10.4025/actascibiolsci.v32i2.5923

    Directory of Open Access Journals (Sweden)

    Norma Maria Barros Benevides

    2010-05-01

    papain in 0.1 M sodium acetate buffer (pH 5.0 containing 5 mM cysteine and 5 mM EDTA, followed by fractionation on ion exchange DEAE-cellulose column with NaCl gradient. The obtained fractions were analyzed by 0.5% agarose gel electrophoresis and the anticoagulant activity measured by the activated partial thromboplastin time (APTT using normal human plasma, and compared to a standard heparin curve (193 IU mg-1. Similar chromatographic profiles of SP were shown on both species, but with distinct mobility patterns, when the SP fractions were compared by electrophoresis. SP eluted with 0.75 M of NaCl modified the APTT, whose anticoagulant activities were only 21.23 and 24.36 IU mg-1 for C. racemosa and C. cupressoides, respectively. Therefore, anticoagulant SP isolated from chlorophyceaes showed effects inferior to heparin, and comparative studies of these molecules are also suggested as auxiliary tools in the identification of algae of the same genus.

  15. Involvement of protein kinase C activation in L-leucine-induced stimulation of protein synthesis in l6 myotubes.

    Science.gov (United States)

    Yagasaki, Kazumi; Morisaki, Naoko; Kitahara, Yoshiro; Miura, Atsuhito; Funabiki, Ryuhei

    2003-11-01

    Effects of leucine and related compounds on protein synthesis were studied in L6 myotubes. The incorporation of [(3)H]tyrosine into cellular protein was measured as an index of protein synthesis. In leucine-depleted L6 myotubes, leucine and its keto acid, alpha-ketoisocaproic acid (KIC), stimulated protein synthesis, while D-leucine did not. Mepacrine, an inhibitor of both phospholipases A(2) and C, canceled stimulatory actions of L-leucine and KIC on protein synthesis. Neither indomethacin, an inhibitor of cyclooxygenase, nor caffeic acid, an inhibitor of lipoxygenase, diminished their stimulatory actions, suggesting no involvement of arachidonic acid metabolism. Conversely, 1-O-hexadecyl-2-O-methylglycerol, an inhibitor of proteinkinase C, significantly canceled the stimulatory actions of L-leucine and KIC on protein synthesis, suggesting an involvement of phosphatidylinositol degradation and activation of protein kinase C. L-Leucine caused a rapid activation of protein kinase C in both cytosol and membrane fractions of the cells. These results strongly suggest that both L-leucine and KIC stimulate protein synthesis in L6 myotubes through activation of phospholipase C and protein kinase C. PMID:19003213

  16. Tribomechanical micronization and activation of whey protein concentrate and zeolite

    Indian Academy of Sciences (India)

    Z Herceg; V Lelas; M Brnčić; B Tripalo; D Ježek

    2004-02-01

    Tribomechanics is a part of physics that is concerned with the study of phenomena that appear during milling under dynamic conditions. Tribomechanical micronization and activation (TMA) of whey protein concentrates (WPC) and zeolites (type clinoptilolite) were carried out. Samples of powdered WPC and zeolite were treated with the laboratory TMA equipment. The treatment was carried out at two various rotor speeds: 16,000 and 22,000 r.p.m. at ambient temperature. Analyses of the particle size and distribution as well as the specific area and scanning electron microscopy were carried out on the powdered WPC and zeolite, before and after the TMA treatment. Suspensions of the WPC and zeolite were treated with ultrasound, just before determining the particle size distribution, at 50 kHz. The results showed that tribomechanical treatment causes significant decrease in particle size, change in particle size distribution and increase in specific area of WPC and zeolite. These changes of the treated materials depend on the type of the material, the level of inserting particles, the planned angle of the impact, internal rubbing and the planned number of impacts. The effects found became stronger as the rotor speed of the TMA equipment increased (16,000 to 22,000 rpm). Ultrasonic treatment of suspension of tribomechanically treated WPC resulted infurther breakdown of partly damaged protein globules as proved with the statistic analyses. No further changes in their granulometric composition were caused by ultrasonic treatment of a suspension of tribomechanically treated zeolite.

  17. Regional citrate anticoagulation in critically ill patients during continuous blood purification

    Institute of Scientific and Technical Information of China (English)

    龚德华; 季大玺; 徐斌; 谢红浪; 刘云; 黎磊石

    2003-01-01

    Objectives To evaluate the safety and define the contraindication of regional citrate anticoagulation treatment on various critically ill patients being treated by continuous blood purification, who also had bleeding tendencies. Methods Forty critically ill patients being treated by continuous blood purification (CBP) were involved in this study. Due to their bleeding tendencies, regional citrate anticoagulation treatment was given to all of them. Those with hepatic function impairment (n=10) were classified as Group A, those with hypoxemia were classified as Group B (n=10), and the others as Group C (n=20). Blood samples were collected before treatment, and at 4, 12, 24, 36, and 48 hour intervals during CBP. These samples then were used arterial blood gas analysis, whole blood activated clotting time (WBACT) pre- and post-filter, and serum ionized calcium examination. Results WBACT pre-filter showed little fluctuant through the 48hr period of CBP, and WBACT post-filter showed obvious prolongation than that of the pre-filter (P<0.05) at all time points. Metabolic acidosis was found in Group A patients before CBP, and improved during CBP. Normal acid-base conditions of patients were disturbed and deteriorated in Group B during CBP, but not in Group C. Serum ionized calcium was maintained at a normal range during CBP in Group A and C patients, but declined significantly in Group B patients (vs. pre-treatment, P<0.05). Conclusions Regional citrate anticoagulation can be safely used in conjunction with CBP treatment for patients with hepatic function impairment , but may induce acidosis and a decline in serum ionized calcium when used with hypoxemic patients.

  18. Efficacy and safety of new oral anticoagulants in prophylaxis and treatment of venous thromboembolism

    Directory of Open Access Journals (Sweden)

    Luca Masotti

    2011-04-01

    Full Text Available One of the main innovation emerged in recent years in the field of venous thromboembolism (VTE has been represented by the clinical development and marketing of new oral anticoagulant agents used for prophylaxis and acute treatment. These drugs are represented by direct thrombin inhibitors (anti-factor IIa and the direct inhibitors of activated factor X (anti-Xa. The main achievement of these new agents is represented by their ease of use without laboratory monitoring or dose adjustment. Dabigatran (anti-factor IIa, rivaroxaban, and apixaban (anti-Xa are in advanced phase of clinical development with concluded phase III trials. Up to now the results of efficacy and safety of phase III clinical trials are available, while phase IV studies are currently ongoing. Overall, the phase III clinical trials showed the non inferiority of new oral anticoagulants in VTE prophylaxis of patients undergone to major orthopedic surgery, such as hip and knee arthroplasty, compared to conventional prophylaxis represented by subcutaneous low molecular weight heparin with similar safety. Moreover dabigatran has shown to be not inferior when compared to warfarin for the prevention of six months VTE recurrences, with a significative lower incidence of bleedings. Awaiting the results of many other ongoing phase III trials, since now it is possible to think that, in the next future, new oral anticoagulants will be widely diffused in clinical practice for their ease of use and feasibility. In this review the Authors analyse the available results of phase III clinical trials for dabigatran, rivaroxaban and apixaban, focusing on the antithrombotic endpoints for prevention and treatment of VTE and the bleeding risk. Moreover synthesis of ongoing trials will be displayed.

  19. Antiplatelet and Anticoagulant Effects of Diterpenes Isolated from the Marine Alga, Dictyota menstrualis

    Directory of Open Access Journals (Sweden)

    Laura de Andrade Moura

    2014-04-01

    Full Text Available Cardiovascular diseases represent a major cause of disability and death worldwide. Therapeutics are available, but they often have unsatisfactory results and may produce side effects. Alternative treatments based on the use of natural products have been extensively investigated, because of their low toxicity and side effects. Marine organisms are prime candidates for such products, as they are sources of numerous and complex substances with ecological and pharmacological effects. In this work, we investigated, through in vitro experiments, the effects of three diterpenes (pachydictyol A, isopachydictyol A and dichotomanol from the Brazilian marine alga, Dictyota menstrualis, on platelet aggregation and plasma coagulation. Results showed that dichotomanol inhibited ADP- or collagen-induced aggregation of platelet-rich plasma (PRP, but failed to inhibit washed platelets (WP. In contrast, pachydictyol A and isopachydictyol A failed to inhibit the aggregation of PRP, but inhibited WP aggregation induced by collagen or thrombin. These diterpenes also inhibited coagulation analyzed by the prothrombin time and activated partial thromboplastin time and on commercial fibrinogen. Moreover, diterpenes inhibited the catalytic activity of thrombin. Theoretical studies using the Osiris Property Explorer software showed that diterpenes have low theoretical toxicity profiles and a drug-score similar to commercial anticoagulant drugs. In conclusion, these diterpenes are promising candidates for use in anticoagulant therapy, and this study also highlights the biotechnological potential of oceans and the importance of bioprospecting to develop medicines.

  20. Enhanced biocontrol activity of Trichoderma through inactivation of a mitogen-activated protein kinase

    OpenAIRE

    Mendoza-Mendoza, Artemio; Pozo, María J.; Grzegorski, Darlene; Martínez, Pedro; García, Juan M.; Olmedo-Monfil, Vianey; Cortés, Carlos; Kenerley, Charles; Herrera-Estrella, Alfredo

    2003-01-01

    The production of lytic enzymes in Trichoderma is considered determinant in its parasitic response against fungal species. A mitogen-activated protein kinase encoding gene, tvk1, from Trichoderma virens was cloned, and its role during the mycoparasitism, conidiation, and biocontrol was examined in tvk1 null mutants. These mutants showed a clear increase in the level of the expression of mycoparasitism-related genes under simulated mycoparasitism and during direct confrontation with the plant ...

  1. Protein implicated in nonsyndromic mental retardation regulates protein kinase A (PKA) activity

    KAUST Repository

    Al-Tawashi, Azza

    2012-02-28

    Mutation of the coiled-coil and C2 domain-containing 1A (CC2D1A) gene, which encodes a C2 domain and DM14 domain-containing protein, has been linked to severe autosomal recessive nonsyndromic mental retardation. Using a mouse model that produces a truncated form of CC2D1A that lacks the C2 domain and three of the four DM14 domains, we show that CC2D1A is important for neuronal differentiation and brain development. CC2D1A mutant neurons are hypersensitive to stress and have a reduced capacitytoformdendritesandsynapsesinculture. Atthebiochemical level,CC2D1Atransduces signals to the cyclic adenosine 3?,5?-monophosphate (cAMP)-protein kinase A (PKA) pathway during neuronal cell differentiation. PKA activity is compromised, and the translocation of its catalytic subunit to the nucleus is also defective in CC2D1A mutant cells. Consistently, phosphorylation of the PKA target cAMP-responsive element-binding protein, at serine 133, is nearly abolished in CC2D1A mutant cells. The defects in cAMP/PKA signaling were observed in fibroblast, macrophage, and neuronal primary cells derived from the CC2D1A KO mice. CC2D1A associates with the cAMP-PKA complex following forskolin treatment and accumulates in vesicles or on the plasma membrane in wild-type cells, suggesting that CC2D1A may recruit the PKA complex to the membrane to facilitate signal transduction. Together, our data show that CC2D1A is an important regulator of the cAMP/PKA signaling pathway, which may be the underlying cause for impaired mental function in nonsyndromic mental retardation patients with CC2D1A mutation. 2012 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Monitoring of anticoagulant therapy in heart disease: considerations for the current assays.

    Science.gov (United States)

    Boroumand, Mohammadali; Goodarzynejad, Hamidreza

    2010-01-01

    Clinicians should be aware of new developments to familiarize themselves with pharmacokinetic and pharmacodynamic characteristics of new anticoagulant agents to appropriately and safely use them. For the moment, cardiologists and other clinicians also require to master currently available drugs, realizing the mechanism of action, side effects, and laboratory monitoring to measure their anticoagulant effects. Warfarin and heparin have narrow therapeutic window with high inter- and intra-patient variability, thereby the use of either drug needs careful laboratory monitoring and dose adjustment to ensure proper antithrombotic protection while minimizing the bleeding risk. The prothrombin time (PT) and the activated partial thromboplastin time (aPTT) are laboratory tests commonly used to monitor warfarin and heparin, respectively. These two tests depend highly on the combination of reagent and instrument utilized. Results for a single specimen tested in different laboratories are variable; this is mostly attributable to the specific reagents and to a much lesser degree to the instrument used. The PT stands alone as the single coagulation test that has undergone the most extensive attempt at assay standardization. The international normalized ratio (INR) was introduced to "normalize" all PT reagents to a World Health Organization (WHO) reference thromboplastin preparation standard, such that a PT measured anywhere in the world would result in an INR value similar to that which would have been achieved had the WHO reference thromboplastin been utilized. However, INRs are reproducible between laboratories for only those patients who are stably anticoagulated with vitamin K antagonists (VKAs) (i.e., at least 6 weeks of VKA therapy), and are not reliable or reproducible between laboratories for patients for whom VKA therapy has recently been started or any other clinical conditions associated with a prolonged PT such as liver disease, disseminated intravascular coagulation

  3. Monitoring of Anticoagulant Therapy in Heart Disease: Considerations for the Current Assays

    Directory of Open Access Journals (Sweden)

    Hamidreza Goodarzynejad

    2010-05-01

    Full Text Available Clinicians should be aware of new developments to familiarize themselves with pharmacokinetic and pharmacodynamic characteristics of new anticoagulant agents to appropriately and safely use them. For the moment, cardiologists and other clinicians also require to master currently available drugs, realizing the mechanism of action, side effects, and laboratory monitoring to measure their anticoagulant effects. Warfarin and heparin have narrow therapeutic window with high inter- and intra-patient variability, thereby the use of either drug needs careful laboratory monitoring and dose adjustment to ensure proper antithrombotic protection while minimizing the bleeding risk. The prothrombin time (PT and the activated partial thromboplastin time (aPTT are laboratory tests commonly used to monitor warfarin and heparin, respectively. These two tests depend highly on the combination of reagent and instrument utilized. Results for a single specimen tested in different laboratories are variable; this is mostly attributable to the specific reagents and to a much lesser degree to the instrument used. The PT stands alone as the single coagulation test that has undergone the most extensive attempt at assay standardization. The international normalized ratio (INR was introduced to ‘‘normalize’’ all PT reagents to a World Health Organization (WHO reference thromboplastin preparation standard, such that a PT measured anywhere in the world would result in an INR value similar to that which would have been achieved had the WHO reference thromboplastin been utilized. However, INRs are reproducible between laboratories for only those patients who are stably anticoagulated with vitamin K antagonists (VKAs (i.e., at least 6 weeks of VKA therapy, and are not reliable or reproducible between laboratories for patients for whom VKA therapy has recently been started or any other clinical conditions associated with a prolonged PT such as liver disease, disseminated

  4. Analysis of Protein in Soybean by Neutron Activation Technique

    International Nuclear Information System (INIS)

    Nitrogen content in soybean was studied by using Neutron Activation Analysis technique through fast neutron at the flux of 2.5 * 1011 n/cm2. sec in the CA-3 out-core irradiation tube of the Thai Research Reactor-1/Modification 1 (TRR-1/M1, Triga Mark 3 type). By measuring gamma ray of 511 keV from 13N of the nuclear reaction, 14N(n, 2n)13N caused by the annihilation of positron disintegrated, the semi-conductor detector (HPGe) was connected with the multi-channel analyzer (MCA) and monitor to display the spectrum range. NH4NO3 was used as the standard for the analysis. The inaccuracy of the analysis caused by other radioisotopes, i.e. potassium, phosphorus and reaction from recoiled proton scattering in soybean was corrected. The data of 27 samples analyzed by neutron activation showed no significant difference in the nitrogen content. The average nitrogen content of all the soybean samples is 7.02% equivalent to protein content of 43.88%

  5. Comparative response of platelet fV and plasma fV to activated protein C and relevance to a model of acute traumatic coagulopathy.

    Directory of Open Access Journals (Sweden)

    James E Campbell

    Full Text Available BACKGROUND: Acute traumatic coagulopathy (ATC has been linked to an increase in activated protein C (aPC from 40 pM in healthy individuals to 175 pM. aPC exerts its activity primarily through cleavage of active coagulation factor Va (fVa. Platelets reportedly possess fVa which is more resistant to aPC cleavage than plasma fVa; this work examines the hypothesis that normal platelets are sufficient to maintain coagulation in the presence of elevated aPC. METHODS: Coagulation responses of normal plasma, fV deficient plasma (fVdp, and isolated normal platelets in fVdp were conducted: prothrombin (PT tests, turbidimetry, and thromboelastography (TEG, including the dose response of aPC on the samples. RESULTS: PT and turbidimetric assays demonstrate that normal plasma is resistant to aPC at doses much higher than those found in ATC. Additionally, an average physiological number of washed normal platelets (200,000 platelets/mm3 was sufficient to eliminate the anti-coagulant effects of aPC up to 10 nM, nearly two orders of magnitude above the ATC concentration and even the steady-state pharmacological concentration of human recombinant aPC, as measured by TEG. aPC also demonstrated no significant effect on clot lysis in normal plasma samples with or without platelets. CONCLUSIONS: Although platelet fVa shows slightly superior resistance to aPC's effects compared to plasma fVa in static models, neither fVa is sufficiently cleaved in simulations of ATC or pharmacologically-delivered aPC to diminish coagulation parameters. aPC is likely a correlative indicator of ATC or may play a cooperative role with other activity altering products generated in ATC.

  6. Activation of pheromone-sensitive neurons is mediated by conformational activation of pheromone-binding protein.

    Science.gov (United States)

    Laughlin, John D; Ha, Tal Soo; Jones, David N M; Smith, Dean P

    2008-06-27

    Detection of volatile odorants by olfactory neurons is thought to result from direct activation of seven-transmembrane odorant receptors by odor molecules. Here, we show that detection of the Drosophila pheromone, 11-cis vaccenyl acetate (cVA), is instead mediated by pheromone-induced conformational shifts in the extracellular pheromone-binding protein, LUSH. We show that LUSH undergoes a pheromone-specific conformational change that triggers the firing of pheromone-sensitive neurons. Amino acid substitutions in LUSH that are predicted to reduce or enhance the conformational shift alter sensitivity to cVA as predicted in vivo. One substitution, LUSH(D118A), produces a dominant-active LUSH protein that stimulates T1 neurons through the neuronal receptor components Or67d and SNMP in the complete absence of pheromone. Structural analysis of LUSH(D118A) reveals that it closely resembles cVA-bound LUSH. Therefore, the pheromone-binding protein is an inactive, extracellular ligand converted by pheromone molecules into an activator of pheromone-sensitive neurons and reveals a distinct paradigm for detection of odorants. PMID:18585358

  7. Extended Anticoagulant and Aspirin Treatment for the Secondary Prevention of Thromboembolic Disease: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Paul E Marik

    Full Text Available Patients who have had an unprovoked deep venous thrombosis (DVT or pulmonary embolus (PE are at a high risk for recurrent venous thromboembolism (VTE. Extended "life-long" anticoagulation has been recommended in these patients. However, the risk benefit ratio of this approach is controversial and the role of the direct oral anticoagulants (DOACs and aspirin is unclear. Furthermore, in some patients with a "weak provoking factor" there is clinical equipoise regarding continuation or cessation of anticoagulant therapy after treatment of the acute VTE event.A systematic review and meta-analysis to determine the risks (major bleeding and benefits (recurrent VTE and mortality of extended anticoagulation with vitamin k antagonists (VKA, DOACs and aspirin in patients with an unprovoked VTE and in those patients with clinical equipoise regarding continuation or cessation of anticoagulant therapy. In addition, we sought to determine the risk of recurrent VTE events once extended anti-thrombotic therapy was discontinued.MEDLINE, Cochrane Register of Controlled Trials, citation review of relevant primary and review articles.Randomized placebo-controlled trials (RCTs that compared the risk of recurrent VTE in patients with an unprovoked DVT or PE who had been treated for at least 3 months with a VKA or a DOAC and were then randomized to receive an oral anti-thrombotic agent or placebo for at least 6 additional months. We included studies that included patients in whom clinical equipoise existed regarding the continuation or cessation of anticoagulant therapy.Independent extraction of articles by both authors using predefined data fields, including study quality indicators. Data were abstracted on study size, study setting, initial event (DVT or PE, percentage of patients where the initial VTE event was unprovoked, the number of recurrent VTE events, major bleeds and mortality during the period of extended anticoagulation in the active treatment and placebo

  8. Activation of tracheal smooth muscle contraction: synergism between Ca2+ and activators of protein kinase C.

    OpenAIRE

    Park, S.; Rasmussen, H

    1985-01-01

    The effects of divalent ionophores (A23187 and ionomycin), Ca2+ channel agonist (BAY K 8644), and protein kinase C (C-kinase) activators [phorbol 12-myristate 13-acetate (PMA), mezerein] on bovine tracheal smooth muscle contraction were investigated. A23187 (5 microM) and ionomycin (0.5 microM) produced a prompt but transient contraction. C-kinase activators either produced no effect--e.g., PMA at 200 nM--or produced a rise in tension that was slow in onset but then gradually increased--e.g.,...

  9. Anticoagulant substance released from human lung mast cells by stimulation with anti-IgE or Ca-ionophore A23187.

    OpenAIRE

    Hayashi, Hisatomo; TSUDA, Takashi; Tsurumi, Naokazu; Takai,Yutaka; Maeda, Masanori; Takahashi,Kiyoshi; Kimura,Ikuro

    1987-01-01

    A significant amount of anticoagulant substance was released along with histamine, when human lung mast cells were stimulated with anti-IgE and Ca-ionophore A23187. Its activity was lost by heparinase, not by chondroitin-ABC lyase or chondroitin-AC lyase, and also inhibited by Polybrene, suggesting it would be heparin.

  10. Anticoagulant substance released from human lung mast cells by stimulation with anti-IgE or Ca-ionophore A23187.

    Directory of Open Access Journals (Sweden)

    Hayashi,Hisatomo

    1987-04-01

    Full Text Available A significant amount of anticoagulant substance was released along with histamine, when human lung mast cells were stimulated with anti-IgE and Ca-ionophore A23187. Its activity was lost by heparinase, not by chondroitin-ABC lyase or chondroitin-AC lyase, and also inhibited by Polybrene, suggesting it would be heparin.

  11. Acidification Activates Toxoplasma gondii Motility and Egress by Enhancing Protein Secretion and Cytolytic Activity.

    Science.gov (United States)

    Roiko, Marijo S; Svezhova, Nadezhda; Carruthers, Vern B

    2014-11-01

    Pathogenic microbes rely on environmental cues to initiate key events during infection such as differentiation, motility, egress and invasion of cells or tissues. Earlier investigations showed that an acidic environment activates motility of the protozoan parasite T. gondii. Conversely, potassium ions, which are abundant in the intracellular milieu that bathes immotile replicating parasites, suppress motility. Since motility is required for efficient parasite cell invasion and egress we sought to better understand its regulation by environmental cues. We found that low pH stimulates motility by triggering Ca2+-dependent secretion of apical micronemes, and that this cue is sufficient to overcome suppression by potassium ions and drive parasite motility, cell invasion and egress. We also discovered that acidification promotes membrane binding and cytolytic activity of perforin-like protein 1 (PLP1), a pore-forming protein required for efficient egress. Agents that neutralize pH reduce the efficiency of PLP1-dependent perforation of host membranes and compromise egress. Finally, although low pH stimulation of microneme secretion promotes cell invasion, it also causes PLP1-dependent damage to host cells, suggesting a mechanism by which neutral extracellular pH subdues PLP1 activity to allow cell invasion without overt damage to the target cell. These findings implicate acidification as a signal to activate microneme secretion and confine cytolytic activity to egress without compromising the viability of the next cell infected. PMID:25375818

  12. Anticoagulant properties of a crude sulfated polysaccharide from the red marine alga Halymenia floresia (Clemente C. Agardh = Propriedades anticoagulantes de um polissacarídeo sulfatado bruto da alga marinha vermelha Halymenia floresia (Clemente C. Agardh

    Directory of Open Access Journals (Sweden)

    Rodrigo César das Neves Amorim

    2011-07-01

    Full Text Available Alternative sources of anticoagulants have arisen as a result of the increasing demand for safer anticoagulant clinical therapy, and the sulfated polysaccharides of seaweeds have gained attention in biomedicine. In this study, crude sulfated polysaccharide fractions (denominated Hf1, Hf2 and Hf3 were obtained from the red marine algaHalymenia floresia and the anticoagulant properties of a soluble crude polysaccharide fraction (Hf2s were assayed. The three differential extractions yielded 38.6%. The polysaccharides are composed mainly of galactose, with small amounts of xylose and glucose. The anticoagulant properties of Hf2s containing 53.8% sulfate and 3% protein was also compared to those of heparin (193.0 IU mg-1 by assays of activated partial thromboplastin time (APTT and thrombin time (TT using normal human plasma. Hf2s showed a higheranticoagulant activity (68.4 IU mg-1 than those of Hf1s and Hf3s, whose activities were 37.6 and 36.6 IU mg-1, respectively. The compound was less active than heparin, but its anticoagulant mechanism suggested that it is dependent on cofactor heparin II to inhibit thrombin activity, but not on cofactors VIII and IX. Therefore, the polysaccharide from H. floresia interfered on coagulation cascade.O aumento da demanda por anticoagulantes para a terapia clínica tem motivado a busca por fontes alternativas de anticoagulantes mais seguros e os polissacarídeos sulfatados de algas marinhas têm ganhado atenção na biomedicina. Objetivou-se obter frações de polissacarídeossulfatados brutos (denominadas Hf1; Hf2 e Hf3 da alga marinha vermelha Halymenia floresia e para avaliar as propriedades anticoagulantes de uma fração polissacarídica bruta solúvel anticoagulante (Hf2s. As três extrações diferenciais renderam 38,60%. Os polissacarídeos são principalmente compostos de galactose com pequenas quantidades de xilose e glucose. As propriedades anticoagulantes da Hf2s, contendo 53,80% de sulfato e 3% de prote

  13. Regulation of orange carotenoid protein activity in cyanobacterial photoprotection

    NARCIS (Netherlands)

    Thurotte, A.; Lopez Igual, R.; Wilson, A.; Comolet, L.; Bourcier de Carbon, C.; Xiao, F.; Kirilovsky, D.

    2015-01-01

    Plants, algae, and cyanobacteria have developed mechanisms to decrease the energy arriving at reaction centers to protect themselves from high irradiance. In cyanobacteria, the photoactive Orange Carotenoid Protein (OCP) and the Fluorescence Recovery Protein are essential elements in this mechanism.

  14. A study of the relationship between the pharmacokinetics and the pharmacodynamics of the 4-hydroxycoumarin anticoagulants warfarin, difenacoum and brodifacoum in the rabbit.

    Science.gov (United States)

    Breckenridge, A M; Cholerton, S; Hart, J A; Park, B K; Scott, A K

    1985-01-01

    The pharmacokinetics and pharmacodynamics of the 4-hydroxycoumarin anticoagulants, brodifacoum, difenacoum, and warfarin have been studied in the rabbit. Sensitive (50 ng ml-1) and specific high performance liquid chromatography assays have been developed for the determination of plasma concentrations of warfarin, brodifacoum and difenacoum. After administration of a single intravenous dose (20 mumol kg-1), plasma concentrations of warfarin underwent mono-exponential decay, with a terminal half-life of 5.6 +/- 0.7 h (mean +/- s.e. mean), whereas plasma concentrations of brodifacoum and difenacoum underwent bi-exponential decay with terminal half-lives of 60.8 +/- 1.9 h and 83.1 +/- 10.3 h respectively. The plasma half-life of brodifacoum in a single patient poisoned with the compound was 487 h. The pharmacological response to the anticoagulants was measured as changes in prothrombin complex activity, from which the rate of clotting factor synthesis was determined. Clotting factor synthesis recovered in a monophasic fashion after a single intravenous dose of warfarin, compared with a more complex biphasic, pattern of recovery of clotting factor synthesis after administration of either brodifacoum or difenacoum. The slope (m) of the intensity of effect-log (amount of drug in the body) curve was derived for each anticoagulant. There was no significant difference in the value of m after single intravenous doses of racemic, R-, and S-warfarin, difenacoum and brodifacoum, which is consistent with the hypothesis that all the 4-hydroxycoumarin anticoagulants produce their anticoagulant effect by acting at the same receptor site, vitamin K epoxide reductase. Determination of the minimum plasma concentration of each anticoagulant that corresponded with the complete inhibition of clotting factor synthesis indicated that racemic warfarin, R-warfarin and brodifacoum have similar potencies in the rabbit and are less potent than S-warfarin and difenacoum. PMID:3978316

  15. Impact of electrically activated water fractions on solubility of meat proteins

    OpenAIRE

    Віннікова, Людмила Григорівна; Пронькіна, Ксенія Володимирівна

    2015-01-01

    The article examines and discusses the influence of electrically activated water on the proteins of muscle tissue. The aim of the study is to improve the solubility of proteins in muscle tissue to achieve greater yields and improve their quality through the use of electrically activated water fractions. The results of the studies of solubility change of sarcoplasmic and myofibrillar proteins are given. It is established the solubility level of sarcoplasmic and myofibrillar proteins in the pre...

  16. [Use of direct oral anticoagulants in the elderly].

    Science.gov (United States)

    Mickley, Frank; Geigenmüller, Grit; Schinköthe, Claudia

    2015-12-01

    Equal safety and efficacy of direct oral anticoagulants as compared to vitamin K antagonists have been shown in elderly and very old patients. The use of these seem to have certain advantages in this special patient cohort: higher drug safety, no need for lab monitoring, less drug-drug interactions and a lower rate of intracranial hemorrhages. However, more data is needed to quantify the exact bleeding risk for geriatric patients. Elderly patients suffer quite frequently from significant comorbidities, such as renal failure, dementia, vision loss etc., which might put them at higher risk to suffer from medication side effects, especially bleeding complications. Routine clinical examinations combined with monitoring of renal function are therefore of paramount importance. Regarding these precautions the use of the new oral anticoagulants in the elderly is hence quite justified and rising. PMID:26625228

  17. Emergent Bleeding in Patients Receiving Direct Oral Anticoagulants.

    Science.gov (United States)

    Summers, Richard L; Sterling, Sarah A

    2016-01-01

    Direct oral anticoagulants (DOACs) offer clinical advantages over warfarin, such as minimal medication and food interactions and fixed dosing without the need for routine monitoring of coagulation status. As with all anticoagulants, bleeding, either spontaneous or provoked, is the most common complication. The long-term use of these drugs is increasing, and there is a crucial need for emergency medicine service professionals to understand the optimal management of associated bleeding. This review aims to describe the indications and pharmacokinetics of available DOACs; to discuss the risk of bleeding; to provide a treatment algorithm to manage DOAC-associated emergency bleeding; and to discuss future directions in bleeding management, including the role of specific reversal agents, such as the recently approved idarucizumab for reversal of the direct thrombin inhibitor dabigatran. Because air medical personnel are increasingly likely to encounter patients receiving DOACs, it is important that they have an understanding of how to manage patients with emergent bleeding. PMID:27255877

  18. Patients' attitude and knowledge about oral anticoagulation therapy

    DEFF Research Database (Denmark)

    Amara, Walid; Larsen, Torben B; Sciaraffia, Elena; Hernández Madrid, Antonio; Chen, Jian; Estner, Heidi; Todd, Derick; Bongiorni, Maria G; Potpara, Tatjana S; Dagres, Nikolaos; Sagnol, Pascal; Blomstrom-Lundqvist, Carina

    2016-01-01

    The purpose of this European Heart Rhythm Association survey was to assess the attitude, level of education, and knowledge concerning oral anticoagulants (OACs) among patients with atrial fibrillation (AF) taking vitamin K antagonists (VKAs), non-VKA oral anticoagulants (NOACs) or antiplatelets. A...... total of 1147 patients with AF [mean age 66 ± 13 years, 529 (45%) women] from 8 selected European countries responded to this survey. The overall use of OACs and antiplatelets was 77 and 15.3%, respectively. Of the patients taking OACs, 67% were on VKAs, 33% on NOACs, and 17.9% on a combination of OACs...... and antiplatelets. Among patients on VKAs, 91% correctly stated the target international normalized ratio (INR) level. The proportion of patients on VKA medication who were aware that monthly INR monitoring was required for this treatment and the proportion of patients on NOAC who knew that renal...

  19. Predictors of recurrent venous thromboembolism and bleeding on anticoagulation.

    Science.gov (United States)

    Menapace, Laurel A; McCrae, Keith R; Khorana, Alok A

    2016-04-01

    The impact of venous thromboembolism (VTE) in the cancer population remains substantial despite significant advances in detecting and treating thrombotic events. While there is extensive literature regarding predictors of first VTE event in cancer patients as well as a validated predictive score, less data exist regarding recurrent VTE in cancer cohorts and associated predictive variables. A similar paucity of data in regard to bleeding events in cancer patients receiving anticoagulation has been observed. This review article will highlight clinical risk factors as well as predictive biomarkers associated with recurrent VTE and bleeding in cancer patients receiving therapeutic anticoagulation. Predictive risk assessment models for cancer-associated recurrent VTE and bleeding are also discussed. PMID:27067987

  20. Self-management of oral anticoagulant therapy in two centers

    DEFF Research Database (Denmark)

    Nilsson, Hanna; Grove, E; Larsen, Torben Bjerregaard;

    endpoints: all-cause mortality, major thromboembolism and bleeding events, percentage of time within therapeutic International Normalized Ratio (INR) target range (TTR) and variance of the INR value. Patient data was obtained from two databases in the two centers, where all data had been prospectively......Self-management of oral anticoagulant therapy in two centers: 11.000 patient-years of follow-up H Nilsson1,2,3, EL Grove2, TB Larsen3, M Maegaard1, TD Christensen1 1Department of Cardiothoracic and Vascular Surgery & Institute of Clinical Medicine, Aarhus University Hospital, Aarhus; 2Department of...... registered. Results: Results are pending but baseline characteristics (age, gender, indication for anticoagulant therapy) and data on all-cause mortality, major thromboembolism and bleeding events, TTR, INR-variance will be presented at the meeting. Conclusions: We hope to find a good quality of treatment...

  1. Difficulties in anticoagulation management during coadministration of warfarin and rifampin.

    Science.gov (United States)

    Lee, C R; Thrasher, K A

    2001-10-01

    The clinical significance of rifampin's induction of warfarin metabolism is well documented, but no published studies or case reports have quantified this interaction with respect to the international normalized ratio (INR). A patient receiving concomitant rifampin and warfarin to treat a mycobacterial infection and intraventricular thrombus, respectively, underwent routine INR testing at a pharmacist-managed anticoagulation clinic to assess his anticoagulation regimen. A 233% increase in warfarin dosage over 4 months proved insufficient to attain a therapeutic INR during long-term rifampin therapy More aggressive titration of the warfarin dosage was needed. In addition, a gradual 70% reduction in warfarin dosage over 4-5 weeks was necessary to maintain a therapeutic INR after rifampin discontinuation, demonstrating the clinically significant offset of this drug interaction. Extensive changes in warfarin dosage are required to attain and maintain a therapeutic INR during the initiation, maintenance, and discontinuation of rifampin. PMID:11601670

  2. Evaluation of a pharmacist-managed anticoagulation clinic.

    Science.gov (United States)

    Cohen, I A; Hutchison, T A; Kirking, D M; Shue, M E

    1985-06-01

    Medical records were retrospectively analyzed to evaluate the success of a pharmacist-managed Anticoagulation Surveillance Clinic (ASC). The 78 patients in group I were followed by the ASC. The 17 patients in Group II were followed by other Veterans Administration Medical Center clinics. Demographic characteristics, warfarin indication and potentially complicating conditions were comparable between the groups. Group I patients had shorter intervals between visits to the clinic than Group II patients. Although not statistically different compared to Group II, Group I patients had better prothrombin time control. Group I patients also had fewer complications per treatment year (6.9% vs 9.0%) and received fewer potentially interacting drugs. The ASC was at least as successful as the other clinics in managing patients on warfarin, and results compared very favorably to those reported in the literature for other anticoagulation clinics. PMID:4019790

  3. AParadigm Shift: The New Novel Oral Anticoagulation Agents.

    Science.gov (United States)

    Saeed, Wajeeha; Burke, James F; Mirrani, Ghazi; Sirinivasa, Minisha; Nabi, Usman; Hayat, Umar; Khan, Zubair; Sardar, Muhammad Rizwan

    2016-07-01

    Atrial fibrillation (AF) is the most common arrhythmia and represents one-third of the arrhythmia-related hospital admissions in the developed countries. Embolic strokes associated with AF are more severe and disabling. Thromboembolic stroke prevention is a major goal in treatment of AF and Warfarin has successfully served this purpose for many years. Drug-drug interaction and regular monitoring with Warfarin pose a significant challenge where health care system has limited resources; and lack of a well-structured health system, hinders regular International Normalized Ratio (INR) monitoring. Novel oral anticoagulants (NOACs) have opened up a new exciting chapter in the field of anticoagulation in non-valvular atrial fibrillation (NVAF). This review discussed the landmark trials that led to the development of NOACs and explored the potentials of these new agents with simultaneous comparison of Warfarin. PMID:27504556

  4. New oral anticoagulants – the newest update in dental surgery

    OpenAIRE

    Dimova, Cena; Kovacevska, Ivona; Angelovska, Bistra

    2013-01-01

    Aim of this study is to review the evidence of different therapy approach, to highlight the areas of major concern, and to suggest specific oral surgery treatment for patients on new oral anticoagulants. A Medline and an extensive hand search were performed on English-language publications beginning in 1971 till now. The pertinent literature and clinical protocols of hospital dentistry departments have been extensively reviewed, presented and discussed. Several evolving clinical practic...

  5. Colorimetric measurement of iron in plasma samples anticoagulated with EDTA.

    OpenAIRE

    Walmsley, T. A.; George, P M; Fowler, R. T.

    1992-01-01

    AIMS: To determine if the iron in EDTA anticoagulated plasma samples can be measured by colorimetric assays using Ferrozine. METHODS: Paired samples of serum and EDTA plasma were obtained from 24 patients and analysed by three commercial iron methods. The EDTA plasmas were also analysed using methods modified by the addition of zinc sulphate or with different concentrations of Ferrozine. The iron contamination of EDTA sample tubes was measured by atomic absorption spectroscopy. RESULTS: Two c...

  6. Anticoagulation in chronic kidney disease patients—the practical aspects

    OpenAIRE

    Hughes, Stephen; Szeki, Iren; Nash, Michael J; Thachil, Jecko

    2014-01-01

    There is an increasing awareness about the risks of arterial and venous thromboembolism (TE) in hospital patients and general public which has led to consideration of thrombosis prevention measures in earnest. Early recognition of the symptoms of TE disease has led to timely administration of antiplatelet and anticoagulant drugs, translating to better outcome in many of these patients. In this respect, patients with chronic kidney disease (CKD) represent a special group. They indeed represent...

  7. New oral anticoagulants in the prevention of stroke

    OpenAIRE

    Konrad Jarząbek; Dawid Bąkowski; Beata Wożakowska-Kapłon

    2013-01-01

    Atrial fibrillation is associated with a few folds higher risk of stroke. Traditional vitamin K antagonists used in the prevention of stroke in patients with non-valvular atrial fibrillation are often not efficient enough due to their interactions with a broad range of substances including medicines or food ingridients and problems with monitoring the treatment. New oral anticoagulants pose an alternative for the vitamin K antagonists. They are equally efficient in the prevention of stroke, ...

  8. Design of Potent and Controllable Anticoagulants Using DNA Aptamers and Nanostructures

    Directory of Open Access Journals (Sweden)

    Abhijit Rangnekar

    2016-02-01

    Full Text Available The regulation of thrombin activity offers an opportunity to regulate blood clotting because of the central role played by this molecule in the coagulation cascade. Thrombin-binding DNA aptamers have been used to inhibit thrombin activity. In the past, to address the low efficacy reported for these aptamers during clinical trials, multiple aptamers have been linked using DNA nanostructures. Here, we modify that strategy by linking multiple copies of various thrombin-binding aptamers using DNA weave tiles. The resulting constructs have very high anticoagulant activity in functional assays owing to their improved cooperative binding affinity to thrombin due to optimized spacing, orientation, and the high local concentration of aptamers. We also report the results of molecular dynamics simulations to gain insight into the solution conformations of the tiles. Moreover, by using DNA strand displacement, we were able to turn the coagulation cascade off and on as desired, thereby enabling significantly better control over blood coagulation.

  9. Rheb Inhibits Protein Synthesis by Activating the PERK-eIF2α Signaling Cascade

    Directory of Open Access Journals (Sweden)

    Richa Tyagi

    2015-02-01

    Full Text Available Rheb, a ubiquitous small GTPase, is well known to bind and activate mTOR, which augments protein synthesis. Inhibition of protein synthesis is also physiologically regulated. Thus, with cell stress, the unfolded protein response system leads to phosphorylation of the initiation factor eIF2α and arrest of protein synthesis. We now demonstrate a major role for Rheb in inhibiting protein synthesis by enhancing the phosphorylation of eIF2α by protein kinase-like ER kinase (PERK. Interplay between the stimulatory and inhibitory roles of Rheb may enable cells to modulate protein synthesis in response to varying environmental stresses.

  10. Experimental studies on the anticoagulant and antithrombotic effects of sodium and calcium pentosan polysulphate.

    Science.gov (United States)

    Giedrojć, J; Radziwon, P; Klimiuk, M; Bielawiec, M; Breddin, H K; Kłoczko, J

    1999-03-01

    In the present study we have compared the antithrombotic and anticoagulant properties of sodium and calcium derivatives of pentosan polysulphate (Na-PPS, Ca-PPS). The antithrombotic effect of these agents have been investigated in an experimental thrombosis model in which rat mesenteric venules diameter of 20-30 microm were injured by well defined Argon laser lesions. Furthermore, the in vivo and in vitro anticoagulant activities (aPTT, Heptest) of these agents have been studied. Thrombus formation was significantly inhibited after s.c. injection of Na-PPS and Ca-PPS in doses above 10 mg/kg. The duration of the antithrombotic effect lasted 8 h for Na-PPS and 12 h for Ca-PPS. After oral administration of Na-PPS an antithrombotic effect was not observed. Oral application of Ca-PPS in doses higher than 20 mg/kg significantly inhibited thrombus formation. Na-PPS and Ca-PPS markedly prolonged clotting time in aPTT and Heptest in concentrations ranging from 0.01 to 0.2 mg/ml rat PTT. Two h after s.c. administration of these agents in a dose 10 mg/kg, the aPTT increased 3-fold and Heptest 2.5-fold compared to controls. After oral application of 50 mg/kg Na-PPS and Ca-PPS no effect on coagulation test could be measured. PMID:10210159

  11. In vivo examination of the anticoagulant effect of the Brassica oleracea methanol extract

    Directory of Open Access Journals (Sweden)

    Khan Rafeeq Alam

    2015-01-01

    Full Text Available The anticoagulant effect of the methanol extract of Brassica oleracea var. capitata (MEB was examined in rabbits. The animals were divided into five groups, each comprising seven animals. Three groups were administered increasing doses of MEB (200, 300, and 500 mg/kg, respectively; one group received warfarin (0.54 mg/kg; animals in the control group received saline (1 ml/day equivalent to the volume of doses applied to the treated and standard animals. Biochemical tests were performed on the 16th and 31st days of dosing. Animals that were administered MEB (500 mg MEB/kg 30 days displayed increases of 24.07 s, 28.79 s and 4.08 s in activated partial thromboplastin (aPTT, fibrinogen (Fg and thrombin time (TT. Compared to the control, the increase in aPTT and Fg was highly significant and the increase in TT was significant. The anticoagulant effect exhibited by MEB in rabbits may be due to inactivation or inhibition of factors affecting coagulation.

  12. Stroke Prevention in Atrial Fibrillation: Understanding the New Oral Anticoagulants Dabigatran, Rivaroxaban, and Apixaban

    Directory of Open Access Journals (Sweden)

    Tan Ru San

    2012-01-01

    Full Text Available Unlike vitamin K antagonists (VKAs, the new oral anticoagulants (NOACs—direct thrombin inhibitor, dabigatran, and direct activated factor X inhibitors, rivaroxaban, and apixaban—do not require routine INR monitoring. Compared to VKAs, they possess relatively rapid onset of action and short halflives, but vary in relative degrees of renal excretion as well as interaction with p-glycoprotein membrane transporters and liver cytochrome P450 metabolic enzymes. Recent completed phase III trials comparing NOACs with VKAs for stroke prevention in atrial fibrillation (AF—the RE-LY, ROCKET AF, and ARISTOTLE trials—demonstrated at least noninferior efficacy, largely driven by significant reductions in haemorrhagic stroke. Major and nonmajor clinically relevant bleeding rates were acceptable compared to VKAs. Of note, the NOACs caused significantly less intracranial haemorrhagic events compared to VKAs, the mechanisms of which are not completely clear. With convenient fixed-dose administration, the NOACs facilitate anticoagulant management in AF in the community, which has hitherto been grossly underutilised. Guidelines should evolve towards simplicity in anticipation of greater use of NOACs among primary care physicians. At the same time, the need for caution with their use in patients with severely impaired renal function should be emphasised.

  13. Coagulation assessment with the new generation of oral anticoagulants.

    Science.gov (United States)

    Pollack, Charles V

    2016-06-01

    Long-term oral anticoagulant (OAC) therapy is used for the treatment and prevention of thrombosis and thromboembolism. As OAC use is so widespread, emergency physicians are likely to encounter patients on anticoagulant therapy in the emergency department (ED) on a regular basis, either for the same reasons as the population in general or as a result of the increased bleeding risk that OAC use entails.The vitamin K antagonist warfarin has been the standard OAC for several decades, but recently, the newer agents dabigatran etexilate, rivaroxaban and apixaban (collectively, novel OACs, non-vitamin K OACs, or simply 'NOACs') have become available for long-term use. Protocols for assessing and managing warfarin-treated patients in the ED are well established and include international normalised ratio (INR) testing, which helps guide patient management. However, the INR does not give an accurate evaluation of coagulation status with NOACs, and alternative tests are therefore needed for use in emergency settings. This paper discusses what information the INR provides for a patient taking warfarin and which coagulation tests can guide the physician when treating patients on one of the NOACs, as well as other differences in emergency anticoagulation management. PMID:25987596

  14. Selection of an aptamer antidote to the anticoagulant drug bivalirudin.

    Directory of Open Access Journals (Sweden)

    Jennifer A Martin

    Full Text Available Adverse drug reactions, including severe patient bleeding, may occur following the administration of anticoagulant drugs. Bivalirudin is a synthetic anticoagulant drug sometimes employed as a substitute for heparin, a commonly used anticoagulant that can cause a condition called heparin-induced thrombocytopenia (HIT. Although bivalrudin has the advantage of not causing HIT, a major concern is lack of an antidote for this drug. In contrast, medical professionals can quickly reverse the effects of heparin using protamine. This report details the selection of an aptamer to bivalirudin that functions as an antidote in buffer. This was accomplished by immobilizing the drug on a monolithic column to partition binding sequences from nonbinding sequences using a low-pressure chromatography system and salt gradient elution. The elution profile of binding sequences was compared to that of a blank column (no drug, and fractions with a chromatographic difference were analyzed via real-time PCR (polymerase chain reaction and used for further selection. Sequences were identified by 454 sequencing and demonstrated low micromolar dissociation constants through fluorescence anisotropy after only two rounds of selection. One aptamer, JPB5, displayed a dose-dependent reduction of the clotting time in buffer, with a 20 µM aptamer achieving a nearly complete antidote effect. This work is expected to result in a superior safety profile for bivalirudin, resulting in enhanced patient care.

  15. [Influence of anticoagulants on the appearance of chronic subdural hematoma].

    Science.gov (United States)

    Krupa, Mariusz; Moskała, Marek; Składzień, Tomasz; Grzywna, Ewelina

    2009-01-01

    In recent years in the Department of Neurotraumatology in Cracow it has been noticed the frequent connection between appearance of chronic subdural hematoma (CSDH) and treatment by anticoagulant medications. The aim of this study is to draw attention to the problem of insufficient control of anticoagulants consumption, especially by patients treated for cardiovascular system diseases that increases the risk of bleeding and CSDH development. The paper is based on data from questionnaires that was sent to patients with CSDH, cured in the Department of Neurotraumatology form 2004 to 2005. Analyzed was the group of 51 patients with chronic subdural hematoma; 37 individuals (72.5%) confirmed taking acetylsalicylic acid in the period of 3 months before admission to the Department, 9 (17.6%) patients answered that they were taking low-molecular weight heparin. One patient (1.9%) was taking chronically derivative of cumarin. The authors would inform that anticoagulant treatment might favour increase of chronic subdural hematoma incidence. It's especially important, because the average life expectancy has been prolonged in Poland and there are more people taking acetylsalicylic acid. This can be an epidemiological problem in future. PMID:20043584

  16. New anticoagulants in the treatment of stroke:future promise

    Institute of Scientific and Technical Information of China (English)

    Emre Kumral; Tuba Cerraho(g)lu (S)irin

    2013-01-01

    Recent evidence is leading to the replacement of vitamin K antagonists,the efficacy of which in preventing stroke in patients with atrial fibrillation (AF) is well established,with better tolerated and more manageable new anticoagulant drugs,with a lower risk of intracranial bleeding,no clear interactions with food,fewer interactions with medications,and no need for frequent laboratory monitoring and dose adjustments.Among new anticoagulants,dabigatran etexilate is a direct,competitive inhibitor of thrombin.It was evaluated for patients with AF in the RE-LY trial,showing lower rates of stroke and systemic embolism at a dose of 150 mg twice daily with similar rates of major hemorrhage compared with warfarin; and non-inferiority compared with warfarin for the prevention of stroke and systemic embolism at a dose of 110 mg twice daily,with lower rates of major bleeding.Beside dabigatran,oral factor X a inhibitors are also emerging for the prevention of thromboembolic events in AF.Despite the obvious advantages of these new oral anticoagulants over vitamin K antagonists,further information is still needed on how to prioritize the patients deriving the greatest benefit from these novel agents on the basis of patient characteristics or drug pharmacokinetics.There is also a need for assessing their long-term efficacy and safety over decades in the real-world setting.

  17. Electroconvulsive therapy and anticoagulation after pulmonary embolism: a case report

    Directory of Open Access Journals (Sweden)

    Julio Cesar Lazaro

    2014-07-01

    Full Text Available Introduction Electroconvulsive therapy (ECT is considered the most effective treatment for catatonia regardless its underlying condition. The rigid fixed posture and immobility observed in catatonia may lead to several clinical complications, of which, pulmonary embolism (PE is one of the most severe. The rapid improvement of the psychiatric condition in catatonia-related PE is essential, since immobility favors the occurrence of new thromboembolic events and further complications. In that scenario, ECT should be considered, based on a risk-benefit analysis, aiming at the faster resolution of the catatonia. Methods Case report and literature review. Results A 66-years-old woman admitted to the psychiatric ward with catatonia due to a depressive episode presented bilateral PE. Clinically stable, but still severely depressed after a trial of antidepressants, she was treated with ECT in the course of full anticoagulation with enoxaparin. After five ECT sessions, her mood was significantly better and she was walking and eating spontaneously. She did not present complications related either to PE or to anticoagulation. After the eighth ECT session, she evolved with hypomania, which was managed with oral medication adjustments. The patient was completely euthymic at discharge. Conclusion The case we presented provides further evidence to the anecdotal case reports on the safety of ECT in the course of concomitant full anticoagulant therapy after PE, and illustrates how, with the proper precautions, the benefits of ECT in such condition might outweigh its risks.

  18. Activation of Coagulation by Administration of Recombinant Factor VIIa Elicits Interleukin 6 (IL-6) and IL-8 Release in Healthy Human Subjects

    Science.gov (United States)

    de Jonge, Evert; Friederich, Philip W.; Vlasuk, George P.; Rote, William E.; Vroom, Margaretha B.; Levi, Marcel; van der Poll, Tom

    2003-01-01

    The activation of coagulation has been shown to contribute to proinflammatory responses in animal and in vitro experiments. Here we report that the activation of coagulation in healthy human subjects by the administration of recombinant factor VIIa also elicits a small but significant increase in the concentrations of interleukin 6 (IL-6) and IL-8 in plasma. This increase was absent when the subjects were pretreated with recombinant nematode anticoagulant protein c2, the inhibitor of tissue factor-factor VIIa. PMID:12738659

  19. Activation of Coagulation by Administration of Recombinant Factor VIIa Elicits Interleukin 6 (IL-6) and IL-8 Release in Healthy Human Subjects

    OpenAIRE

    de Jonge, Evert; Friederich, Philip W.; Vlasuk, George P.; Rote, William E.; Vroom, Margaretha B.; Levi, Marcel; van der Poll, Tom

    2003-01-01

    The activation of coagulation has been shown to contribute to proinflammatory responses in animal and in vitro experiments. Here we report that the activation of coagulation in healthy human subjects by the administration of recombinant factor VIIa also elicits a small but significant increase in the concentrations of interleukin 6 (IL-6) and IL-8 in plasma. This increase was absent when the subjects were pretreated with recombinant nematode anticoagulant protein c2, the inhibitor of tissue f...

  20. Partial Fractionation of Venoms from Two Iranian Vipers, Echis carinatus and Cerastes persicus Fieldi and Evaluation of Their Antiplatelet Activity.

    Science.gov (United States)

    Mehdizadeh Kashani, Toktam; Vatanpour, Hossein; Zolfagharian, Hossein; Hooshdar Tehrani, Hasan; Heydari, Mohammad Hossein; Kobarfard, Farzad

    2012-01-01

    Platelet aggregation inhibitory effect and anticoagulant properties of fractions separated from the venoms of Cerastes persicus fieldi and Echis carinatus were investigated. The partial fractionation was performed on a Sephadex G-100 column. Two fractions separated from Cerastes persicus fieldi showed anti platelet aggregation activity on ADP (200 μM)-induced platelet aggregation (ca 80% inhibition). Attempts to measure the antiplatelet aggregation activity of crude Echis carinatus venom and its fractions were not successful due to the protein coagulation of the plasma samples after the addition of venom. Anticoagulant activities of venoms were also evaluated. Total venom of Echis carinatus showed anti coagulant activity in PT test, while its fractions showed procoagulant activity. PMID:24250552

  1. Antioxidative activity of whey protein hydrolysates in a liposomal system.

    Science.gov (United States)

    Peña-Ramos, E A; Xiong, Y L

    2001-12-01

    Whey protein isolate (WPI) with or without preheating (90 degrees C for 5 min) was hydrolyzed for 0.5 to 6 h using four pure enzymes (pepsin, papain, trypsin, and chymotrypsin) and three commercial crude proteases. After determining the degree of hydrolysis, the hydrolysates were incubated (37 degrees C, 1 h) with a liposome oxidizing system (50 mM FeCl3/0.1 mM ascorbate, pH 7.0). Lipid oxidation was measured by determining the concentrations of TBA-reactive substances (TBARS). The degree of hydrolysis of WPI ranged from 4 to 37% depending on the enzymes used and whether the substrate was heated or not. WPI hydrolysates prepared by pure enzyme treatments did not prevent TBARS formation in the oxidative model system, but WPI hydrolyzed by the commercial crude enzymes, especially protease F, exhibited antioxidant activity. The antioxidative potential of hydrolyzed WPI was not affected by the degree of hydrolysis, and it was improved by preheat treatment in only some samples. PMID:11814013

  2. Enhanced transcriptional activation by E2 proteins from the oncogenic human papillomaviruses.

    OpenAIRE

    Kovelman, R; Bilter, G K; Glezer, E; Tsou, A Y; Barbosa, M S

    1996-01-01

    A systematic comparison of transcriptional activation by papillomavirus E2 proteins revealed that the E2 proteins from high-risk human papillomaviruses (human papillomavirus type 16 [HPV-16] and HPV-18) are much more active than are the E2 proteins from low-risk HPVs (HPV-6b and HPV-11). Despite the tropism of HPVs for particular epithelial cell types, this difference in transcriptional activation was observed in a number of different epithelial and nonepithelial cells. The enhanced activitie...

  3. Tissue-dependent regulation of protein tyrosine kinase activity during embryonic development

    OpenAIRE

    1991-01-01

    Protein tyrosine kinase activity was assayed in a variety of chicken tissues during embryonic development and in the adult. In some tissues protein tyrosine kinase activity decreased during embryonic development; however, in other tissues it remained high throughout development, it contrast to the level of protein tyrosine phosphorylation, which decreased during development. The highest levels of tyrosine kinase activity were detected in 17-d embryonic brain although only low levels of protei...

  4. Azorella compacta methanolic extract induces apoptosis via activation of mitogen-activated protein kinase.

    Science.gov (United States)

    Sung, Min Hee; Kwon, Ok-Kyoung; Oh, Sei-Ryang; Lee, Joongku; Park, Sang-Hong; Han, Sang Bae; Ahn, Kyung-Seop

    2015-11-01

    Azorella compacta Phil. (AC) is an alpine medicinal plant used traditionally for antibacterial treatment. Recent studies have revealed that this plant also has anti‑diabetic effects, but that it is toxic. The present study investigated the underlying mechanisms of action of AC extract against human leukemia HL60 cells. Apoptosis induction was measured by MTT assay, fluorescence microscopy, DNA fragmentation assay, flow cytometric analysis, reverse transcription quantitative polymerase chain reaction and western blot analyses. It was found that AC extract inhibited the growth of HL60 and other cancer cell lines in a dose‑dependent manner. The cytotoxic effects of AC extract on HL60 cells were associated with apoptosis characterized by DNA fragmentation and dose‑dependent increases in Annexin V‑positive cells, as determined by flow cytometric analysis. AC‑extract‑induced apoptosis was accompanied by activated/cleaved caspase‑3, caspase‑9 and poly(adenosine diphosphate‑ribose) polymerase (PARP). The increases in apoptosis were also associated with decreases of the apoptosis-inhibitor B-cell lymphoma 2 (Bcl‑2), upregulation of pro‑apoptotic Bcl-2-associated X (Bax) protein and downregulation of anti‑apoptotic Bcl extra large protein. Furthermore, western blot analysis of mitogen-activated protein kinase (MAPK)-associated proteins indicated that treatment with AC extract increased the levels of c-Jun N-terminal kinase, extracellular signal-regulated kinase and p38. In addition, the expression of Bax and cleaved PARP was blocked when AC treatment was performed in the presence of MAPK inhibitors. It was therefore concluded that AC induced apoptosis in human leukemia HL60 cells via an intrinsic pathway controlled through MAPK-associated signaling. PMID:26397193

  5. Extracellular matrix inspired surface functionalization with heparin, fibronectin and VEGF provides an anticoagulant and endothelialization supporting microenvironment

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xue [Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Liu, Tao [Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai’an (China); Chen, Yuan [Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Zhang, Kun [Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); School of Life Science, Zhengzhou University, Zhengzhou (China); Maitz, Manfred F. [Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Hohe Str. 06, 01069 Dresden (Germany); Pan, Changjiang [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai’an (China); Chen, Junying, E-mail: chenjy@263.net [Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Huang, Nan [Key Laboratory of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China)

    2014-11-30

    Highlights: • Surface modification with fibronectin, heparin and VEGF could selectively anticoagulant and promote endothelialization. • The bioactivity of biomolecules was more efficiently maintained via specific intermolecular interaction. • Poly-l-lysine interlayer was more feasible and the degradation product had no harm to human body. - Abstract: The biocompatibility of currently used coronary artery stent is still far from perfect, which closely related to insufficient endothelialization and thrombus formation. In this study, heparin, fibronectin and VEGF were immobilized on Ti surface to construct a multifunctional microenvironment with favorable properties to inhibit thrombosis formation and promote endothelialization simultaneously. The microenvironment on Ti surface was characterized in detail and demonstrated that the Hep/Fn/VEGF biofunctional coating was constructed successfully on Ti surface. The influence of surface properties such as chemical composition, roughness, hydrophilicity, and binding density of biomolecules on the performances of hemocompatibility and cytocompatibility was evaluated and discussed. Modified surface significantly enhanced the AT III binding density and prolonged the clotting time. In vitro platelet adhesion and activation assays further proved that the modified surface presented favorable anti-coagulant property. In addition, the proliferation of endothelial progenitor cells (EPCs) and endothelial cells (ECs) on the Hep/Fn/VEGF biofunctional coating was significantly promoted. In conclusion, the Hep/Fn/VEGF biofunctional coating was successfully constructed with desirable anticoagulant and endothelialization supporting properties. This work may provide a promising approach for biofunctional surface modification of coronary artery stent to acquire a desired multifunctional microenvironment.

  6. Trials of the anticoagulants rodenticide WBA 8119 against confined colonies of warfarin-resistant house mice (Mus musculus L.).

    Science.gov (United States)

    Rowe, F P; Bradfield, A

    1976-12-01

    The efficacy of the newly developed anticoagulant rodenticide WBA 8119 was evaluated against the house mouse (Mus musculus L.) using individual and family groups of warfarin-resistant animals. WBA 8119 at 0-002%, 0-005% and 0-01% in pinhead oatmeal bait gave complete kills of mice in 'no-choice' feeding tests carried out in cages and small pens. In replicated 21-day treatments on families of mice confined in larger pens and conditioned to feeding on plain foods, the overall mortalities obtained using the three formulated poison baits were 71/72, 62/63 and 57/57 respectively. The results of the WBA 8119 toxicity tests are considered in relation to previous findings on other anticoagulant rodenticides, particularly difenacoum. In equivalent tests, WBA 8119 performed better than difenacoum. The data thus support the laboratory findings that WBA 8119 is the most active anticoagulant so far tested for the control of warfarin-resistant house mice. PMID:1069822

  7. Trials of the anticoagulant rodenticide WBA 8119 against confined colonies of warfarin-resistant house mice (Mus musculus L.).

    Science.gov (United States)

    Roew, F. P.; Bradfield, A.

    1976-01-01

    The efficacy of the newly developed anticoagulant rodenticide WBA 8119 was evaluated against the house mouse (Mus musculus L.) using individual and family groups of warfarin-resistant animals. WBA 8119 at 0-002%, 0-005% and 0-01% in pinhead oatmeal bait gave complete kills of mice in 'no-choice' feeding tests carried out in cages and small pens. In replicated 21-day treatments on families of mice confined in larger pens conditioned to feeding on plain foods, the overall mortalities obtained using the three formulated poison baits were 71/72, 62/63 and 57/57 respectively. The results of the WBA 8119 toxicity tests are considered in relation to previous findings on other anticoagulant rodenticides, particularly difenacoum. In equivalents tests, WBA 8119 performed better than difenacoum. The data thus suport the laboratory findings that WBA 8119 is the most active anticoagulant so far tested for the control of warfarin-resistant house mice. PMID:1069821

  8. Extracellular matrix inspired surface functionalization with heparin, fibronectin and VEGF provides an anticoagulant and endothelialization supporting microenvironment

    International Nuclear Information System (INIS)

    Highlights: • Surface modification with fibronectin, heparin and VEGF could selectively anticoagulant and promote endothelialization. • The bioactivity of biomolecules was more efficiently maintained via specific intermolecular interaction. • Poly-l-lysine interlayer was more feasible and the degradation product had no harm to human body. - Abstract: The biocompatibility of currently used coronary artery stent is still far from perfect, which closely related to insufficient endothelialization and thrombus formation. In this study, heparin, fibronectin and VEGF were immobilized on Ti surface to construct a multifunctional microenvironment with favorable properties to inhibit thrombosis formation and promote endothelialization simultaneously. The microenvironment on Ti surface was characterized in detail and demonstrated that the Hep/Fn/VEGF biofunctional coating was constructed successfully on Ti surface. The influence of surface properties such as chemical composition, roughness, hydrophilicity, and binding density of biomolecules on the performances of hemocompatibility and cytocompatibility was evaluated and discussed. Modified surface significantly enhanced the AT III binding density and prolonged the clotting time. In vitro platelet adhesion and activation assays further proved that the modified surface presented favorable anti-coagulant property. In addition, the proliferation of endothelial progenitor cells (EPCs) and endothelial cells (ECs) on the Hep/Fn/VEGF biofunctional coating was significantly promoted. In conclusion, the Hep/Fn/VEGF biofunctional coating was successfully constructed with desirable anticoagulant and endothelialization supporting properties. This work may provide a promising approach for biofunctional surface modification of coronary artery stent to acquire a desired multifunctional microenvironment

  9. AMP-activated protein kinase (AMPK) activation regulates in vitro bone formation and bone mass.

    Science.gov (United States)

    Shah, M; Kola, B; Bataveljic, A; Arnett, T R; Viollet, B; Saxon, L; Korbonits, M; Chenu, C

    2010-08-01

    Adenosine 5'-monophosphate-activated protein kinase (AMPK), a regulator of energy homeostasis, has a central role in mediating the appetite-modulating and metabolic effects of many hormones and antidiabetic drugs metformin and glitazones. The objective of this study was to determine if AMPK can be activated in osteoblasts by known AMPK modulators and if AMPK activity is involved in osteoblast function in vitro and regulation of bone mass in vivo. ROS 17/2.8 rat osteoblast-like cells were cultured in the presence of AMPK activators (AICAR and metformin), AMPK inhibitor (compound C), the gastric peptide hormone ghrelin and the beta-adrenergic blocker propranolol. AMPK activity was measured in cell lysates by a functional kinase assay and AMPK protein phosphorylation was studied by Western Blotting using an antibody recognizing AMPK Thr-172 residue. We demonstrated that treatment of ROS 17/2.8 cells with AICAR and metformin stimulates Thr-172 phosphorylation of AMPK and dose-dependently increases its activity. In contrast, treatment of ROS 17/2.8 cells with compound C inhibited AMPK phosphorylation. Ghrelin and propranolol dose-dependently increased AMPK phosphorylation and activity. Cell proliferation and alkaline phosphatase activity were not affected by metformin treatment while AICAR significantly inhibited ROS 17/2.8 cell proliferation and alkaline phosphatase activity at high concentrations. To study the effect of AMPK activation on bone formation in vitro, primary osteoblasts obtained from rat calvaria were cultured for 14-17days in the presence of AICAR, metformin and compound C. Formation of 'trabecular-shaped' bone nodules was evaluated following alizarin red staining. We demonstrated that both AICAR and metformin dose-dependently increase trabecular bone nodule formation, while compound C inhibits bone formation. When primary osteoblasts were co-treated with AICAR and compound C, compound C suppressed the stimulatory effect of AICAR on bone nodule formation

  10. Regulation of AMP-activated protein kinase by natural and synthetic activators.

    Science.gov (United States)

    Grahame Hardie, David

    2016-01-01

    The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status that is almost universally expressed in eukaryotic cells. While it appears to have evolved in single-celled eukaryotes to regulate energy balance in a cell-autonomous manner, during the evolution of multicellular animals its role has become adapted so that it also regulates energy balance at the whole body level, by responding to hormones that act primarily on the hypothalamus. AMPK monitors energy balance at the cellular level by sensing the ratios of AMP/ATP and ADP/ATP, and recent structural analyses of the AMPK heterotrimer that have provided insight into the complex mechanisms for these effects will be discussed. Given the central importance of energy balance in diseases that are major causes of morbidity or death in humans, such as type 2 diabetes, cancer and inflammatory disorders, there has been a major drive to develop pharmacological activators of AMPK. Many such activators have been described, and the various mechanisms by which these activate AMPK will be discussed. A particularly large class of AMPK activators are natural products of plants derived from traditional herbal medicines. While the mechanism by which most of these activate AMPK has not yet been addressed, I will argue that many of them may be defensive compounds produced by plants to deter infection by pathogens or grazing by insects or herbivores, and that many of them will turn out to be inhibitors of mitochondrial function. PMID:26904394

  11. Regulation of AMP-activated protein kinase by natural and synthetic activators

    Directory of Open Access Journals (Sweden)

    David Grahame Hardie

    2016-01-01

    Full Text Available The AMP-activated protein kinase (AMPK is a sensor of cellular energy status that is almost universally expressed in eukaryotic cells. While it appears to have evolved in single-celled eukaryotes to regulate energy balance in a cell-autonomous manner, during the evolution of multicellular animals its role has become adapted so that it also regulates energy balance at the whole body level, by responding to hormones that act primarily on the hypothalamus. AMPK monitors energy balance at the cellular level by sensing the ratios of AMP/ATP and ADP/ATP, and recent structural analyses of the AMPK heterotrimer that have provided insight into the complex mechanisms for these effects will be discussed. Given the central importance of energy balance in diseases that are major causes of morbidity or death in humans, such as type 2 diabetes, cancer and inflammatory disorders, there has been a major drive to develop pharmacological activators of AMPK. Many such activators have been described, and the various mechanisms by which these activate AMPK will be discussed. A particularly large class of AMPK activators are natural products of plants derived from traditional herbal medicines. While the mechanism by which most of these activate AMPK has not yet been addressed, I will argue that many of them may be defensive compounds produced by plants to deter infection by pathogens or grazing by insects or herbivores, and that many of them will turn out to be inhibitors of mitochondrial function.

  12. A specific, transmembrane interface regulates fibroblast activation protein (FAP) homodimerization, trafficking and exopeptidase activity.

    Science.gov (United States)

    Wonganu, Benjamaporn; Berger, Bryan W

    2016-08-01

    Fibroblast activation protein (FAP) is a cell-surface serine protease which promotes invasiveness of certain epithelial cancers and is therefore a potential target for cancer drug development and delivery. Unlike dipeptidyl peptidase IV (DPPIV), FAP exhibits prolyl endopeptidase activity and is active as a homodimer with specificity for type I collagen. The mechanism that regulates FAP homodimerization and its relation to prolyl endopeptidase activity is not completely understood. Here, we investigate key residues in the FAP TM domain that may be significant for FAP homodimerization. Mutations to predicted TM interfacial residues (G10L, S14L, and A18L) comprising a small-X3-small motif reduced FAP TM-CYTO dimerization relative to wild type as measured using the AraTM assay, whereas predicted off-interface residues showed no significant change from wild type. The results implied that the predicted small-X3-small dimer interface affect stabilization of FAP TM-CYTO homodimerization. Compared with FAPwild-type, the interfacial TM residue G10L significantly decreased FAP endopeptidase activity more than 25%, and also reduced cell-surface versus intracellular expression relative to other interfacial residues S14L and A18L. Thus, our results suggest FAP dimerization is important for both trafficking and protease activity, and is dependent on a specific TM interface. PMID:27155568

  13. Evolutionary Conservation of a GPCR-Independent Mechanism of Trimeric G Protein Activation

    Science.gov (United States)

    Coleman, Brantley D.; Marivin, Arthur; Parag-Sharma, Kshitij; DiGiacomo, Vincent; Kim, Seongseop; Pepper, Judy S.; Casler, Jason; Nguyen, Lien T.; Koelle, Michael R.; Garcia-Marcos, Mikel

    2016-01-01

    Trimeric G protein signaling is a fundamental mechanism of cellular communication in eukaryotes. The core of this mechanism consists of activation of G proteins by the guanine-nucleotide exchange factor (GEF) activity of G protein coupled receptors. However, the duration and amplitude of G protein-mediated signaling are controlled by a complex network of accessory proteins that appeared and diversified during evolution. Among them, nonreceptor proteins with GEF activity are the least characterized. We recently found that proteins of the ccdc88 family possess a Gα-binding and activating (GBA) motif that confers GEF activity and regulates mammalian cell behavior. A sequence similarity-based search revealed that ccdc88 genes are highly conserved across metazoa but the GBA motif is absent in most invertebrates. This prompted us to investigate whether the GBA motif is present in other nonreceptor proteins in invertebrates. An unbiased bioinformatics search in Caenorhabditis elegans identified GBAS-1 (GBA and SPK domain containing-1) as a GBA motif-containing protein with homologs only in closely related worm species. We demonstrate that GBAS-1 has GEF activity for the nematode G protein GOA-1 and that the two proteins are coexpressed in many cells of living worms. Furthermore, we show that GBAS-1 can activate mammalian Gα-subunits and provide structural insights into the evolutionarily conserved determinants of the GBA–G protein interface. These results demonstrate that the GBA motif is a functional GEF module conserved among highly divergent proteins across evolution, indicating that the GBA-Gα binding mode is strongly constrained under selective pressure to mediate receptor-independent G protein activation in metazoans. PMID:26659249

  14. Evolutionary Conservation of a GPCR-Independent Mechanism of Trimeric G Protein Activation.

    Science.gov (United States)

    Coleman, Brantley D; Marivin, Arthur; Parag-Sharma, Kshitij; DiGiacomo, Vincent; Kim, Seongseop; Pepper, Judy S; Casler, Jason; Nguyen, Lien T; Koelle, Michael R; Garcia-Marcos, Mikel

    2016-03-01

    Trimeric G protein signaling is a fundamental mechanism of cellular communication in eukaryotes. The core of this mechanism consists of activation of G proteins by the guanine-nucleotide exchange factor (GEF) activity of G protein coupled receptors. However, the duration and amplitude of G protein-mediated signaling are controlled by a complex network of accessory proteins that appeared and diversified during evolution. Among them, nonreceptor proteins with GEF activity are the least characterized. We recently found that proteins of the ccdc88 family possess a Gα-binding and activating (GBA) motif that confers GEF activity and regulates mammalian cell behavior. A sequence similarity-based search revealed that ccdc88 genes are highly conserved across metazoa but the GBA motif is absent in most invertebrates. This prompted us to investigate whether the GBA motif is present in other nonreceptor proteins in invertebrates. An unbiased bioinformatics search in Caenorhabditis elegans identified GBAS-1 (GBA and SPK domain containing-1) as a GBA motif-containing protein with homologs only in closely related worm species. We demonstrate that GBAS-1 has GEF activity for the nematode G protein GOA-1 and that the two proteins are coexpressed in many cells of living worms. Furthermore, we show that GBAS-1 can activate mammalian Gα-subunits and provide structural insights into the evolutionarily conserved determinants of the GBA-G protein interface. These results demonstrate that the GBA motif is a functional GEF module conserved among highly divergent proteins across evolution, indicating that the GBA-Gα binding mode is strongly constrained under selective pressure to mediate receptor-independent G protein activation in metazoans. PMID:26659249

  15. The biphasic virulence activities of gingipains: activation and inactivation of host proteins.

    Science.gov (United States)

    Imamura, Takahisa; Travis, James; Potempa, Jan

    2003-12-01

    Gingipains are trypsin-like cysteine proteinases produced by Porphyromonas gingivalis, a major causative bacterium of adult periodontitis. Rgps (HRgpA and RgpB) and Kgp are specific for -Arg-Xaa- and -Lys-Xaa- peptide bonds, respectively. HRgpA and Kgp are non-covalent complexes containing separate catalytic and adhesion/hemagglutinin domains, while RgpB has only a catalytic domain with a primary structure essentially identical to that of the cata-lytic subunit of HRgpA. The multiple virulence activities of gingipains are reviewed in view of the biphasic mechanisms: activation and inactivation of host proteins. Rgps enhanced vascular permeability through prekallikrein activation or direct bradykinin release in combination with Kgp. This Rgp action is potentially associated with gingival edema and crevicular fluid production. Rgps activate the blood coagulation system, leading to progression of inflammation and consequent alveolar bone loss in the periodontitis site. Rgps also activate protease-activated receptors and induce platelet aggregation, which, together with the coagulation-inducing activity, may explain an emerging link between periodontitis and cardiovascular disease. Kgp is the most potent fibrinogen/fibrin degrading enzyme of the three gingipains in human plasma, being involved in the bleeding tendency at the diseased gingiva. Gingipains stimulate expression of matrix metalloproteinases (MMPs) in fibroblasts and activate secreted latent MMPs that can destroy periodontal tissues. Gingipains degrade cytokines, components of the complement system and several receptors, including macrophage CD14, T cell CD4 and CD8, thus perturbing the host-defense systems and thereby facilitating sustained colonization of P. gingivalis. Gingipains are potent virulence factors of P. gingivalis, and in many regards their pathogenic activities constitute new mechanisms of bacterial virulence. PMID:14683429

  16. Isolation and characterization of a protein C activator from tropical moccasin venom.

    Science.gov (United States)

    Nakagaki, T; Kazim, A L; Kisiel, W

    1990-06-15

    A protease from the venom of the tropical moccasin (Agkistrodon bilineatus) that activates protein C was purified to homogeneity by ion-exchange and gel permeation chromatography. The purified protease is a glycoprotein, and exhibited a molecular weight of 35,000 and 38,000 in SDS-PAGE under non-reducing and reducing conditions, respectively. The purified protease readily activated human protein C and steady-state kinetic parameters indicated an apparent Km for human protein C of 1.7 microM and an apparent kcat of 0.02 sec-1. Calcium inhibited the activation of human protein C by the venom protease (Ki = 93 microM). Amino-terminal sequence analysis revealed that the tropical moccasin protein C activator was highly homologous to the protein C activator isolated from Southern copperhead venom. PMID:2385829

  17. Stroke prevention in atrial fibrillation: established oral anticoagulants versus novel anticoagulants-translating clinical trial data into practice.

    Science.gov (United States)

    Ezekowitz, Michael D; Spahr, Judy; Ghosh, Pradeepto; Corelli, Kathryn

    2014-09-01

    Anticoagulation for stroke prevention in atrial fibrillation (AF) is effective. Pivotal trials RE-LY, ROCKET AF, ARISTOTLE, and ENGAGE-AF TIMI 48 tested novel agents against warfarin (W). In RE-LY, an open-label trial, dabigatran 150 mg BID (D150) was superior (35%) and 110 mg BID (D110) was noninferior to W. D150 reduced ischemic strokes by 25% and intracerebral bleeds by 74%, but increased major GI bleeds by 0.5 % per year. In ROCKET AF, a double-blind study, rivaroxaban 20 mg daily, downtitrated to 15 mg daily (if CrCl was 80; weight, 1.5 mg) was superior for safety (31%), efficacy (21%), and all-cause mortality (11%). In ENGAGE-AF TIMI 48, edoxaban 60 mg once daily (30 mg once daily if CrCl 30-50 ml/min, weight <60 kg, or concomitant verapamil or quinidine) was noninferior to W for efficacy, but reduced major bleeding (20%). To translate clinical trials to practice, understanding the disease and each anticoagulant is essential. For all novel agents, rapid anticoagulation, absence of monitoring, and a short half-life differentiate them from W. Bleed rates were either noninferior or lower than for W, without an antidote. Patient compliance is critical. Knowledge of renal function is essential and maintaining patients on therapy is key. PMID:24880227

  18. Patient costs in anticoagulation management: a comparison of primary and secondary care.

    OpenAIRE

    Parry, D; Bryan, S; Gee, K; Murray, E.; Fitzmaurice, D

    2001-01-01

    BACKGROUND: The demand for anticoagulation management is increasing. This has led to care being provided in non-hospital settings. While clinical studies have similarly demonstrated good clinical care in these settings, it is still unclear as to which alternative is the most efficient. AIM: To determine the costs borne by patients when attending an anticoagulation management clinic in either primary or secondary care and to use this information to consider the cost-effectiveness of anticoagul...

  19. Citrate pharmacokinetics and calcium levels during high-flux dialysis with regional citrate anticoagulation

    OpenAIRE

    Kozik-Jaromin, Justyna; Nier, Volker; Heemann, Uwe; Kreymann, Bernhard; Böhler, Joachim

    2009-01-01

    Background. Regional citrate anticoagulation is a very effective anticoagulation method for haemodialysis. However, it is not widely used, primarily due to the risk of hypocalcaemia. We studied citrate and calcium kinetics to better understand safety aspects of this anticoagulation method. Methods. During 15 haemodialysis treatments with a calcium-free dialysis solution, citrate was infused pre-dialyser and calcium was substituted post-dialyser. Systemic and extracorporeal citrate and calcium...

  20. Cheese from Ultrafiltered Milk : whey proteins and chymosin activity

    NARCIS (Netherlands)

    Buijsse, C.

    1999-01-01

    The manufacture of (semi-)hard cheese from ultrafiltered milk (UF-cheese) enables the partial incorporation of whey proteins in the cheese, thereby increasing its yield. The transfer of whey proteins in curd from (UF-)milk was studied in relation to the degree of ultrafiltration of the milk and the