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Sample records for activatable fibrinolysis inhibitor

  1. Thrombin activatable fibrinolysis inhibitor (TAFI in cord blood.

    Directory of Open Access Journals (Sweden)

    Krzysztof Góralczyk

    2007-03-01

    Full Text Available Thrombin activatable fibrinolysis inhibitor (TAFI is a plasma zymogene (procarboxypeptidase B which can decrease fibrinolysis and thus act as a haemostatic factor. TAFI is now extensively studied in many complications as well as in physiological and complicated pregnancy. The question we posed in the present study was whether TAFI antigen is present in cord blood plasma. The study group consisted of 38 parturient women, 26 primiparous and 12 multiparous with normal course of pregnancy and delivery. The cord blood was sampled from the cord vein, and the mother's blood from the antecubital vein. 3.2% sodium citrate was used as an anticoagulant. TAFIa/ai antigen was measured by ELISA method. TAFIa/ai antigen was identified in all samples of cord blood plasma. Its level was 91.50 ng/ml (range: 71.76 - 160.77 ng/ml vs. 55.46 ng/ml (range: 39.77 - 68.54 ng/ml in the mother's blood, which means that the level of TAFIa/ai antigen was significantly higher in fetal blood than in maternal blood (p<0.00001. TAFIa/ai antigen is an integral component of cord blood plasma. The concentration of TAFIa/ai antigen is about two times higher in fetal blood than in maternal blood.

  2. A functional single nucleotide polymorphism in the thrombin-activatable fibrinolysis inhibitor (TAFI) gene associates with outcome of meningococcal disease

    NARCIS (Netherlands)

    Kremer Hovinga, J. A.; Franco, R. F.; Zago, M. A.; ten Cate, Hugo; Westendorp, R. G. J.; Reitsma, P. H.

    2004-01-01

    In meningococcal sepsis, disseminated intravascular coagulation with deposition of fibrin and formation of microthrombi occurs in various organs and enhanced inhibition of fibrinolysis is associated with adverse outcome. Recently, TAFI (thrombin-activatable fibrinolysis inhibitor) was identified as

  3. Biochemical characterization of bovine plasma thrombin-activatable fibrinolysis inhibitor (TAFI)

    DEFF Research Database (Denmark)

    Valnickova, Zuzana; Thaysen-Andersen, Morten; Højrup, Peter

    2009-01-01

    -activatable fibrinolysis inhibitor (TAFI), and recombinant human TAFI have recently been solved. In light of these recent advances, we have characterized authentic bovine TAFI biochemically and compared it to human TAFI. RESULTS: The four N-linked glycosylation sequons within the activation peptide were all occupied...

  4. Factor XI dependent and independent activation of thrombin activatable fibrinolysis inhibitor (TAFI) in plasma associated with clot formation

    NARCIS (Netherlands)

    Bouma, B. N.; Mosnier, L. O.; Meijers, J. C.; Griffin, J. H.

    1999-01-01

    Thrombin Activatable Fibrinolysis Inhibitor (TAFI) also known as plasma procarboxypeptidase B is activated by relatively high concentrations of thrombin in a reaction stimulated by thrombomodulin. In plasma an intact factor XI-dependent feed back loop via the intrinsic pathway is necessary to

  5. Binding characteristics of thrombin-activatable fibrinolysis inhibitor to streptococcal surface collagen-like proteins A and B

    NARCIS (Netherlands)

    Seron, Mercedes Valls; Plug, Tom; Marquart, J. Arnoud; Marx, Pauline F.; Herwald, Heiko; de Groot, Philip G.; Meijers, Joost C. M.

    2011-01-01

    Streptococcus pyogenes is the causative agent in a wide range of diseases in humans. Thrombin-activatable fibrinolysis inhibitor (TAFI) binds to collagen-like proteins ScIA and ScIB at the surface of S. pyogenes. Activation of TAFI at this surface redirects inflammation from a transient to chronic

  6. Thrombin-activatable fibrinolysis inhibitor activity in healthy and diseased dogs

    DEFF Research Database (Denmark)

    Jessen, Lisbeth Rem; Wiinberg, Bo; Kjelgaard-Hansen, Mads

    2010-01-01

    Background: In people, increased thrombin-activatable fibrinolysis inhibitor (TAFI) antigen has been associated with increased risk of thrombosis, and decreased TAFI may contribute to bleeding diathesis. TAFI activity in dogs has been described in experimental models, but not in dogs...... with spontaneous disease. Objective: The aim of this study was to compare TAFI activity in healthy dogs with TAFI activity in dogs with spontaneous disease. Methods: Plasma samples from 20 clinically healthy Beagles and from 35 dogs with various diseases were analyzed using a commercial chromogenic assay...... that measured TAFI activity relative to activity in standardized pooled human plasma. Results: Median TAFI activity for the 20 Beagles was 46.1% (range 32.2-70.8%) compared with 62.6% (29.1-250%) for the 35 diseased dogs, and 14/35 (40%) had TAFI activities >the upper limit for controls. The highest individual...

  7. Thrombin-activatable fibrinolysis inhibitor is degraded by Salmonella enterica and Yersinia pestis.

    Science.gov (United States)

    Valls Serón, M; Haiko, J; DE Groot, P G; Korhonen, T K; Meijers, J C M

    2010-10-01

     Pathogenic bacteria modulate the host coagulation system to evade immune responses or to facilitate dissemination through extravascular tissues. In particular, the important bacterial pathogens Salmonella enterica and Yersinia pestis intervene with the plasminogen/fibrinolytic system. Thrombin-activatable fibrinolysis inhibitor (TAFI) has anti-fibrinolytic properties as the active enzyme (TAFIa) removes C-terminal lysine residues from fibrin, thereby attenuating accelerated plasmin formation.  Here, we demonstrate inactivation and cleavage of TAFI by homologous surface proteases, the omptins Pla of Y. pestis and PgtE of S. enterica. We show that omptin-expressing bacteria decrease TAFI activatability by thrombin-thrombomodulin and that the anti-fibrinolytic potential of TAFIa was reduced by recombinant Escherichia coli expressing Pla or PgtE. The functional impairment resulted from C-terminal cleavage of TAFI by the omptins.  Our results indicate that TAFI is degraded directly by the omptins PgtE of S. enterica and Pla of Y. pestis. This may contribute to the ability of PgtE and Pla to damage tissue barriers, such as fibrin, and thereby to enhance spread of S. enterica and Y. pestis during infection. © 2010 International Society on Thrombosis and Haemostasis.

  8. Thrombin activatable fibrinolysis inhibitor and clot lysis time in pregnant patients with antiphospholipid syndrome: relationship with pregnancy outcome and thrombosis.

    Science.gov (United States)

    Martinez-Zamora, Maria Angeles; Tassies, Dolors; Carmona, Francisco; Espinosa, Gerard; Cervera, Ricard; Reverter, Juan Carlos; Balasch, Juan

    2009-12-01

    Antiphospholipid syndrome (APS) pregnancies are associated with thrombotic obstetric complications, despite treatment. This study evaluated Thrombin Activatable Fibrinolysis Inhibitor (TAFI) levels, TAFI gene polymorphisms and Clot Lysis Time (CLT) in pregnant patients with APS in relation to pregnancy outcome and thrombosis. Group 1 consisted of 67 pregnant patients with APS. Group 2 included 66 pregnant patients with uneventful term pregnancies and delivery. Patients were sampled during each trimester and at baseline. TAFI antigen and CLT and two polymorphisms of the TAFI gene, Ala147Thr and +1542C/G, were determined. Significantly prolonged CLT was found at baseline in Group 1. Allele distribution of the TAFI gene polymorphisms was similar in both groups. Basal TAFI and CLT in patients with APS having an adverse or a good obstetrical outcome were similar. Comparison of TAFI and CLT baseline levels in patients with APS with or without previous thrombosis showed no statistical differences. Patients with APS have impairment in fibrinolysis evidenced by prolonged CLT at baseline. TAFI and CLT do not seem to be useful as markers of obstetric outcome or risk of thrombosis in patients with APS.

  9. Thrombin activatable fibrinolysis inhibitor (TAFI) - A possible link between coagulation and complement activation in the antiphospholipid syndrome (APS).

    Science.gov (United States)

    Grosso, Giorgia; Vikerfors, Anna; Woodhams, Barry; Adam, Mariette; Bremme, Katarina; Holmström, Margareta; Ågren, Anna; Eelde, Anna; Bruzelius, Maria; Svenungsson, Elisabet; Antovic, Aleksandra

    2017-10-01

    Thrombosis and complement activation are pathogenic features of antiphospholipid syndrome (APS). Their molecular link is Plasma carboxypeptidase-B, also known as thrombin activatable fibrinolysis inhibitor (TAFIa), which plays a dual role: anti-fibrinolytic, by cleaving carboxyl-terminal lysine residues from partially degraded fibrin, and anti-inflammatory, by downregulating complement anaphylatoxins C3a and C5a. To investigate the levels of TAFI (proenzyme) and TAFIa (active enzyme) in relation to complement activation, fibrin clot permeability and fibrinolytic function in clinical and immunological subsets of 52 APS patients and 15 controls. TAFI (pAPS patients compared to controls. Furthermore, TAFIa was increased (pAPS patients affected by arterial thrombosis compared to other APS-phenotypes. Positive associations were found between TAFI and age, fibrinogen and C5a, and between TAFIa and age, fibrinogen and thrombomodulin. TAFI and TAFIa levels were increased in patients with APS as a potential response to complement activation. Interestingly, TAFI activation was associated with arterial thrombotic APS manifestations. Thus, TAFIa may be considered a novel biomarker for arterial thrombosis in APS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Activated thrombin-activatable fibrinolysis inhibitor (TAFIa) attenuates breast cancer cell metastatic behaviors through inhibition of plasminogen activation and extracellular proteolysis

    International Nuclear Information System (INIS)

    Bazzi, Zainab A.; Lanoue, Danielle; El-Youssef, Mouhanned; Romagnuolo, Rocco; Tubman, Janice; Cavallo-Medved, Dora; Porter, Lisa A.; Boffa, Michael B.

    2016-01-01

    Thrombin activatable fibrinolysis inhibitor (TAFI) is a plasma zymogen, which can be converted to activated TAFI (TAFIa) through proteolytic cleavage by thrombin, plasmin, and most effectively thrombin in complex with the endothelial cofactor thrombomodulin (TM). TAFIa is a carboxypeptidase that cleaves carboxyl terminal lysine and arginine residues from protein and peptide substrates, including plasminogen-binding sites on cell surface receptors. Carboxyl terminal lysine residues play a pivotal role in enhancing cell surface plasminogen activation to plasmin. Plasmin has many critical functions including cleaving components of the extracellular matrix (ECM), which enhances invasion and migration of cancer cells. We therefore hypothesized that TAFIa could act to attenuate metastasis. To assess the role of TAFIa in breast cancer metastasis, in vitro migration and invasion assays, live cell proteolysis and cell proliferation using MDA-MB-231 and SUM149 cells were carried out in the presence of a TAFIa inhibitor, recombinant TAFI variants, or soluble TM. Inhibition of TAFIa with potato tuber carboxypeptidase inhibitor increased cell invasion, migration and proteolysis of both cell lines, whereas addition of TM resulted in a decrease in all these parameters. A stable variant of TAFIa, TAFIa-CIIYQ, showed enhanced inhibitory effects on cell invasion, migration and proteolysis. Furthermore, pericellular plasminogen activation was significantly decreased on the surface of MDA-MB-231 and SUM149 cells following treatment with various concentrations of TAFIa. Taken together, these results indicate a vital role for TAFIa in regulating pericellular plasminogen activation and ultimately ECM proteolysis in the breast cancer microenvironment. Enhancement of TAFI activation in this microenvironment may be a therapeutic strategy to inhibit invasion and prevent metastasis of breast cancer cells

  11. Discovery of thrombin activatable fibrinolysis inhibitor (TAFI)

    NARCIS (Netherlands)

    Bertina, R.M.; Tilburg, N.H. van; Haverkate, F.; Bouma, B.N.; Borne, P.A.K. von dem; Meijers, J.C.M.; Campbell, W.; Eaton, D.; Hendriks, D.F.; Willemse, J.L.

    2006-01-01

    CAS: blood clotting factor 11, 9013-55-2; thrombin, 9002-04-4; tissue plasminogen activator, 105913-11-9; protein C, 60202-16-6; Carboxypeptidase U, 3.4.17.20; Protein C; Tissue Plasminogen Activator, 3.4.21.68

  12. Thrombin-activatable fibrinolysis inhibitor is degraded by Salmonella enterica and Yersinia pestis

    NARCIS (Netherlands)

    Valls Serón, M.; Haiko, J.; de Groot, P. G.; Korhonen, T. K.; Meijers, J. C. M.

    2010-01-01

    Background: Pathogenic bacteria modulate the host coagulation system to evade immune responses or to facilitate dissemination through extravascular tissues. In particular, the important bacterial pathogens Salmonella enterica and Yersinia pestis intervene with the plasminogen/fibrinolytic system.

  13. Plasminogen activator inhibitor-1 suppresses endogenous fibrinolysis in a canine model of pulmonary embolism

    International Nuclear Information System (INIS)

    Reilly, C.F.; Fujita, T.; Hutzelmann, J.E.; Mayer, E.J.; Shebuski, R.J.

    1991-01-01

    Plasminogen activator inhibitor-1 (PAI-1), the specific, fast-acting inhibitor of tissue-type plasminogen activator (t-PA), binds to fibrin and has been found in high concentrations within arterial thrombi. These findings suggest that the localization of PAI-1 to a thrombus protects that same thrombus from fibrinolysis. In this study, clot-bound PAI-1 was assessed for its ability to suppress clot lysis in vivo. Autologous, canine whole blood clots were formed in the presence of increasing amounts of activated PAI-1 (0-30 micrograms/ml). Approximately 6-8% of the PAI-1 bound to the clots under the experimental conditions. Control and PAI-1-enriched clots containing iodine-125-labeled fibrin (ogen) were homogenized, washed to remove nonbound elements, and delivered to the lungs of anesthetized dogs where the homogenates subsequently underwent lysis by the endogeneous fibrinolytic system. 125I-labeled fibrin degradation products appeared in the blood of control animals within 10 minutes and were maximal by 90 minutes. PAI-1 reduced fibrin degradation product release in a dose-responsive manner at all times between 30 minutes and 5 hours (greater than or equal to 76% inhibition at 30 minutes, PAI-1 greater than or equal to 6 micrograms/ml). PAI-1 also suppressed D-dimer release from clots containing small amounts of human fibrin (ogen). t-PA administration attenuated the effects of PAI-1, whereas latent PAI-1 (20 micrograms/ml) had no effect on clot lysis. Blood levels of PA and PAI activity remained unaltered during these experiments. The results indicate that PAI-1 markedly inhibits endogenous fibrinolysis in vivo and, moreover, suggest that the localization of PAI-1 to a forming thrombus is an important physiological mechanism for subsequent thrombus stabilization

  14. Thrombin-activatable fibrinolysis inhibitor binds to Streptococcus pyogenes by interacting with collagen-like proteins A and B

    NARCIS (Netherlands)

    Pahlman, Lisa I.; Marx, Pauline F.; Morgelin, Matthias; Lukomski, Slawomir; Meijers, Joost C. M.; Herwald, Heiko

    2007-01-01

    Regulation of proteolysis is a critical element of the host immune system and plays an important role in the induction of pro- and anti-inflammatory reactions in response to infection. Some bacterial species take advantage of these processes and recruit host proteinases to their surface in order to

  15. Interaction of fucoidan with proteases and inhibitors of coagulation and fibrinolysis.

    Science.gov (United States)

    Minix, R; Doctor, V M

    1997-09-01

    The interactions of fucoidan with glutamic plasminogen (Glu-Plg), two-chain tissue plasminogen activator (t-PA), LMwt-urokinase, thrombin, and antithrombin III (AT-III) were investigated using fucoidan-sepharose affinity chromatography. The results showed 1) a high degree of affinity between fucoidan-sepharose and Glu-Plg; Lmwt-urokinase and thrombin while t-Pa and AT-III did not bind with fucoidan-sepharose. 2) The double reciprocal plot for the LMwt-urokinase activation of Glu-Plg showed that plasminogen activator inhibitor (PAI-1) inhibited this reaction in a noncompetitive manner and that the presence of fucoidan decreased Km for this interaction by 50% and increased Kcat by 30-fold, 3) The double reciprocal plot for the t-PA activation of Glu-Plg showed that PAI-1 inhibited this reaction in a competitive manner and that fucoidan in conjunction with 6-aminohexanoic acid (6-AH) increased Kcat for this interaction by 5-fold without affecting Km. 4) Fucoidan enhanced the interaction of thrombin with both AT-III and heparin cofactor II (HC-II) and it was more effective than unfractionated heparin of LMwt-heparin in enhancing the interaction of HC-II with thrombin.

  16. Variable Resistance to Plasminogen Activator Initiated Fibrinolysis for Intermediate-Risk Pulmonary Embolism.

    Directory of Open Access Journals (Sweden)

    William B Stubblefield

    Full Text Available We examine the clinical significance and biomarkers of tissue plasminogen activator (tPA-catalyzed clot lysis time (CLT in patients with intermediate-risk pulmonary embolism (PE.Platelet-poor, citrated plasma was obtained from patients with PE. Healthy age- and sex-matched patients served as disease-negative controls. Fibrinogen, α2-antiplasmin, plasminogen, thrombin activatable fibrinolysis inhibitor (TAFI, plasminogen activator Inhibitor 1 (PAI-1, thrombin time and D-dimer were quantified. Clotting was induced using CaCl2, tissue factor, and phospholipid. Lysis was induced using 60 ng/mL tPA. Time to 50% clot lysis (CLT was assessed by both thromboelastography (TEG and turbidimetry (A405.Compared with disease-negative controls, patients with PE exhibited significantly longer mean CLT on TEG (+2,580 seconds, 95% CI 1,380 to 3,720 sec. Patients with PE and a short CLT who were treated with tenecteplase had increased risk of bleeding, whereas those with long CLT had significantly worse exercise tolerance and psychometric testing for quality of life at 3 months. A multivariate stepwise removal regression model selected PAI-1 and TAFI as predictive biomarkers of CLT.The CLT from TEG predicted increased risk of bleeding and clinical failure with tenecteplase treatment for intermediate-risk PE. Plasmatic PAI-1 and TAFI were independent predictors of CLT.

  17. Variable Resistance to Plasminogen Activator Initiated Fibrinolysis for Intermediate-Risk Pulmonary Embolism.

    Science.gov (United States)

    Stubblefield, William B; Alves, Nathan J; Rondina, Matthew T; Kline, Jeffrey A

    2016-01-01

    We examine the clinical significance and biomarkers of tissue plasminogen activator (tPA)-catalyzed clot lysis time (CLT) in patients with intermediate-risk pulmonary embolism (PE). Platelet-poor, citrated plasma was obtained from patients with PE. Healthy age- and sex-matched patients served as disease-negative controls. Fibrinogen, α2-antiplasmin, plasminogen, thrombin activatable fibrinolysis inhibitor (TAFI), plasminogen activator Inhibitor 1 (PAI-1), thrombin time and D-dimer were quantified. Clotting was induced using CaCl2, tissue factor, and phospholipid. Lysis was induced using 60 ng/mL tPA. Time to 50% clot lysis (CLT) was assessed by both thromboelastography (TEG) and turbidimetry (A405). Compared with disease-negative controls, patients with PE exhibited significantly longer mean CLT on TEG (+2,580 seconds, 95% CI 1,380 to 3,720 sec). Patients with PE and a short CLT who were treated with tenecteplase had increased risk of bleeding, whereas those with long CLT had significantly worse exercise tolerance and psychometric testing for quality of life at 3 months. A multivariate stepwise removal regression model selected PAI-1 and TAFI as predictive biomarkers of CLT. The CLT from TEG predicted increased risk of bleeding and clinical failure with tenecteplase treatment for intermediate-risk PE. Plasmatic PAI-1 and TAFI were independent predictors of CLT.

  18. Stabilization versus inhibition of TAFIa by competitive inhibitors in vitro

    NARCIS (Netherlands)

    Walker, J.B.; Hughes, B.; James, I.; Haddock, P.; Kluft, C.; Bajzar, L.

    2003-01-01

    Two competitive inhibitors of TAFIa (activated thrombin-activable fibrinolysis inhibitor), 2-guanidinoethyl-mercaptosuccinic acid and potato tuber carboxypeptidase inhibitor, variably affect fibrinolysis of clotted human plasma. Depending on their concentration, the inhibitors shortened, prolonged,

  19. The significance of fibrin binding by plasminogen activator inhibitor 1 for the mechanism of tissue-type plasminogen activator-mediated fibrinolysis

    NARCIS (Netherlands)

    Stringer, H. A.; Pannekoek, H.

    1995-01-01

    The specific, reversible interaction between plasminogen activator inhibitor 1 (PAI-1) and intact fibrin polymers was studied using both purified components and isolated activated platelets as a source of PAI-1. A key reagent in these experiments is a PAI-1 mutant, having its P1 reactive center

  20. The euglobulin clot lysis time to assess the impact of nanoparticles on fibrinolysis

    Energy Technology Data Exchange (ETDEWEB)

    Minet, Valentine, E-mail: valentine.minet@unamur.be; Alpan, Lutfiye; Mullier, François [University of Namur – UNamur, Department of Pharmacy, Namur Thrombosis and Hemostasis Center (NTHC), Namur Nanosafety Center (NNC), NAmur Research Institute for Life Sciences NARILIS (Belgium); Toussaint, Olivier [Laboratory of Cellular Biochemistry and Biology (URBC) (Belgium); Lucas, Stéphane [University of Namur (UNamur), Research Centre for the Physics of Matter and Radiation (PMR-LARN), Namur Nanosafety Center NNC, NAmur Research Institute for Life Sciences NARILIS (Belgium); Dogné, Jean-Michel; Laloy, Julie, E-mail: julie.laloy@unamur.be [University of Namur – UNamur, Department of Pharmacy, Namur Thrombosis and Hemostasis Center (NTHC), Namur Nanosafety Center (NNC), NAmur Research Institute for Life Sciences NARILIS (Belgium)

    2015-07-15

    Nanoparticles (NPs) are developed for many applications in various fields, including nanomedicine. The NPs used in nanomedicine may disturb homeostasis in blood. Secondary hemostasis (blood coagulation) and fibrinolysis are complex physiological processes regulated by activators and inhibitors. An imbalance of this system can either lead to the development of hemorrhages or thrombosis. No data are currently available on the impact of NPs on fibrinolysis. The objectives of this study are (1) to select a screening test to study ex vivo the impact of NPs on fibrinolysis and (2) to test NPs with different physicochemical properties. Euglobulin clot lysis time test was selected to screen the impact of some NPs on fibrinolysis using normal pooled plasma. A dose-dependent decrease in the lysis time was observed with silicon dioxide and silver NPs without disturbing the fibrin network. Carbon black, silicon carbide, and copper oxide did not affect the lysis time at the tested concentrations.

  1. Molecular Imaging with Activatable Reporter Systems

    Directory of Open Access Journals (Sweden)

    Gang Niu, Xiaoyuan Chen

    2012-01-01

    Full Text Available Molecular imaging is a newly emerged multiple disciplinary field that aims to visualize, characterize and quantitatively measure biological processes at cellular and molecular levels in humans and other living systems. A reporter gene is a piece of DNA encoding reporter protein, which presents as a readily measurable phenotype that can be distinguished easily from the background of endogenous protein. After being transferred into cells of organ systems (transgenes, the reporter gene can be utilized to visualize transcriptional and posttranscriptional regulation of gene expression, protein-protein interactions, or trafficking of proteins or cells in living subjects. Herein, we review previous classification of reporter genes and regroup the reporter gene based imaging as basic, inducible and activatable, based on the regulation of reporter gene transcription and post-translational modification of reporter proteins. We then focus on activatable reporters, in which the signal can be activated at the posttranslational level for visualizing protein-protein interactions, protein phosphorylation or tertiary structure changes. The applications of several types of activatable reporters will also be summarized. We conclude that activatable reporter imaging can benefit both basic biomedical research and drug development.

  2. Routine Early Angioplasty after Fibrinolysis

    DEFF Research Database (Denmark)

    Wang, Zhipeng; Liang, Bo; Mei, Qibing

    2009-01-01

    patients in the group that underwent routine early PCI than in the group that received standard treatment received clopidogrel (Ppatients who undergo PCI, as well as in those who do not, is well established,1...... with early beta-blocker therapy is taken into consideration.3 The overall benefit of clopidogrel and beta-blocker therapy could have influenced the outcome in patients who underwent early PCI. These facts leave the conclusion of the TRANSFER-AMI trial still highly uncertain.......To the Editor: Cantor et al. report that there is a significantly reduced rate of ischemic complications among patients with myocardial infarction with ST-segment elevation who are transferred for PCI within 6 hours after fibrinolysis. However, Table 2 of the article shows that significantly more...

  3. Salmeterol enhances pulmonary fibrinolysis in healthy volunteers

    NARCIS (Netherlands)

    Maris, Nico A.; de Vos, Alex F.; Bresser, Paul; van der Zee, Jaring S.; Jansen, Henk M.; Levi, Marcel; van der Poll, Tom

    2007-01-01

    OBJECTIVE: Various lung diseases are associated with local activation of coagulation and concurrent inhibition of fibrinolysis. Although salmeterol, a beta2-adrenoceptor agonist with profound bronchodilatory properties, has been studied extensively, the effects of this compound on the pulmonary

  4. Tunable protease-activatable virus nanonodes.

    Science.gov (United States)

    Judd, Justin; Ho, Michelle L; Tiwari, Abhinav; Gomez, Eric J; Dempsey, Christopher; Van Vliet, Kim; Igoshin, Oleg A; Silberg, Jonathan J; Agbandje-McKenna, Mavis; Suh, Junghae

    2014-05-27

    We explored the unique signal integration properties of the self-assembling 60-mer protein capsid of adeno-associated virus (AAV), a clinically proven human gene therapy vector, by engineering proteolytic regulation of virus-receptor interactions such that processing of the capsid by proteases is required for infection. We find the transfer function of our engineered protease-activatable viruses (PAVs), relating the degree of proteolysis (input) to PAV activity (output), is highly nonlinear, likely due to increased polyvalency. By exploiting this dynamic polyvalency, in combination with the self-assembly properties of the virus capsid, we show that mosaic PAVs can be constructed that operate under a digital AND gate regime, where two different protease inputs are required for virus activation. These results show viruses can be engineered as signal-integrating nanoscale nodes whose functional properties are regulated by multiple proteolytic signals with easily tunable and predictable response surfaces, a promising development toward advanced control of gene delivery.

  5. Effects of Puff-Adder Venom on Coagulation, Fibrinolysis and ...

    African Journals Online (AJOL)

    The in vitro and in vivo haematological effects of puffadder (Bitis arietans) venom in the baboon (Papio ursinus) with regard to its effect on coagulation, fibrinolysis and platelet aggregation were studied. There is a delay in the intrinsic coagulation mechanism with fibrinolysis and in vitro fibrinogenolysis. Normal human ...

  6. No increased systemic fibrinolysis in women with heavy menstrual bleeding

    NARCIS (Netherlands)

    Wiewel-Verschueren, S.; Knol, H. M.; Lisman, T.; Bogchelman, D. H.; Kluin-Nelemans, J. C.; van der Zee, A.G.J.; Mulder, A.B.; Meijer, K.

    BackgroundBleeding disorders have been recognized as important etiologic or contributory factors in women with heavy menstrual bleeding. Fibrinolysis in the endometrium plays a role in heavy menstrual bleeding. It is unknown whether increased systemic fibrinolysis might also increase the risk of

  7. Endogenous fibrinolysis facilitates clot retraction in vivo.

    Science.gov (United States)

    Samson, Andre L; Alwis, Imala; Maclean, Jessica A A; Priyananda, Pramith; Hawkett, Brian; Schoenwaelder, Simone M; Jackson, Shaun P

    2017-12-07

    Clot retraction refers to the process whereby activated platelets transduce contractile forces onto the fibrin network of a thrombus, which over time increases clot density and decreases clot size. This process is considered important for promoting clot stability and maintaining blood vessel patency. Insights into the mechanisms regulating clot retraction at sites of vascular injury have been hampered by a paucity of in vivo experimental models. By pairing localized vascular injury with thrombin microinjection in the mesenteric circulation of mice, we have demonstrated that the fibrin network of thrombi progressively compacts over a 2-hour period. This was a genuine retraction process, as treating thrombi with blebbistatin to inhibit myosin IIa-mediated platelet contractility prevented shrinkage of the fibrin network. Real-time confocal analysis of fibrinolysis after recombinant tissue-type plasminogen activator (tPA) administration revealed that incomplete proteolysis of fibrin polymers markedly facilitated clot retraction. Similarly, inhibiting endogenous fibrinolysis with tranexamic acid reduced retraction of fibrin polymers in vivo. In vitro clot retraction experiments indicated that subthreshold doses of tPA facilitated clot retraction through a plasmin-dependent mechanism. These effects correlated with changes in the elastic modulus of fibrin clots. These findings define the endogenous fibrinolytic system as an important regulator of clot retraction, and show that promoting clot retraction is a novel and complementary means by which fibrinolytic enzymes can reduce thrombus size. © 2017 by The American Society of Hematology.

  8. Progression of symptomatic intracranial large artery atherosclerosis is associated with a proinflammatory state and impaired fibrinolysis.

    Science.gov (United States)

    Arenillas, Juan F; Alvarez-Sabín, José; Molina, Carlos A; Chacón, Pilar; Fernández-Cadenas, Israel; Ribó, Marc; Delgado, Pilar; Rubiera, Marta; Penalba, Anna; Rovira, Alex; Montaner, Joan

    2008-05-01

    The molecular pathways involved in the progression of intracranial large artery atherosclerosis (ILA) are largely unknown. Our objective was to prospectively study the relationship between circulating levels of inflammatory markers and fibrinolysis inhibitors, and the risk of progression of symptomatic ILA. Seventy-five consecutive patients with first-ever symptomatic intracranial atherostenosis were studied. Blood levels of C-reactive protein (CRP), E-selectin, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, matrix metalloproteinases 1, 2, 3, 8, 9, 10, and 13, plasminogen activator inhibitor-1 (PAI-1), and lipoprotein(a) were measured 3 months after the qualifying stroke or transient ischemic attack. Thereafter, patients underwent long-term transcranial Doppler follow-up to detect progression of ILA. During a median follow-up time of 23 months, 25 (33%) patients showed ILA progression. Multivariable adjusted Cox regression models and Kaplan-Meier curves showed that high baseline level of CRP, E-selectin, intercellular adhesion molecule-1, matrix metalloproteinase 9, PAI-1, and lipoprotein(a) predicted ILA progression independently of vascular risk factors. Of them, only CRP (CRP>5.5 mg/L; HR, 5.4 [2.3 to 12.7]; P=0.0001) and PAI-1 (PAI-1>23.1 ng/mL; HR, 2.4 [1.0 to 5.8]; P=0.05) predicted ILA progression also independently of the other studied molecules. Progression of symptomatic ILA is associated with a proinflammatory state, as reflected by high levels of inflammatory markers, and with defective fibrinolysis, as indicated by raised concentrations of endogenous fibrinolysis inhibitors.

  9. Does calcium channel blockade and beta-adrenergic blockade affect platelet function and fibrinolysis to a varying degree?

    DEFF Research Database (Denmark)

    Fornitz, Gitte Gleerup; Mehlsen, J; Winther, K

    1995-01-01

    as the fast-acting inhibitor against tissue plasminogen activator usually termed PAI-1. During atenolol and isradipine therapy, blood pressure (BP) was equally reduced (p ... tended to improve fibrinolysis, as shown by a decrease in PAI, 1 h after exercise. Reducing BP with isradipine or atenolol results in a similar decrease in platelet activity and PAI-level, tested at rest and 1 h after rest, respectively. During exercise, platelet activity increased during atenolol...

  10. Importance of Endogenous Fibrinolysis in Platelet Thrombus Formation.

    Science.gov (United States)

    Gue, Ying X; Gorog, Diana A

    2017-08-25

    The processes of thrombosis and coagulation are finely regulated by endogenous fibrinolysis maintaining healthy equilibrium. When the balance is altered in favour of platelet activation and/or coagulation, or if endogenous fibrinolysis becomes less efficient, pathological thrombosis can occur. Arterial thrombosis remains a major cause of morbidity and mortality in the world despite advances in medical therapies. The role endogenous fibrinolysis in the pathogenesis of arterial thrombosis has gained increasing attention in recent years as it presents novel ways to prevent and treat existing diseases. In this review article, we discuss the role of endogenous fibrinolysis in platelet thrombus formation, methods of measurement of fibrinolytic activity, its role in predicting cardiovascular diseases and clinical outcomes and future directions.

  11. Hyperglycemia stimulates coagulation, whereas hyperinsulinemia impairs fibrinolysis in healthy humans

    NARCIS (Netherlands)

    Stegenga, Michiel E.; van der Crabben, Saskia N.; Levi, Marcel; de Vos, Alex F.; Tanck, Michael W.; Sauerwein, Hans P.; van der Poll, Tom

    2006-01-01

    Type 2 diabetes and insulin resistance syndromes are associated with an increased risk for cardiovascular and thrombotic complications. A disturbed balance between coagulation and fibrinolysis has been implicated in the pathogenesis hereof. To determine the selective effects of hyperglycemia and

  12. Identification of polymorphisms in the 5'-untranslated region of the TAFI gene: relationship with plasma TAFI levels and risk of venous thrombosis

    NARCIS (Netherlands)

    Franco, R. F.; Fagundes, M. G.; Meijers, J. C.; Reitsma, P. H.; Lourenço, D.; Morelli, V.; Maffei, F. H.; Ferrari, I. C.; Piccinato, C. E.; Silva, W. A.; Zago, M. A.

    2001-01-01

    BACKGROUND AND OBJECTIVES: Thrombin activatable fibrinolysis inhibitor (TAFI) plays an important role in hemostasis, functioning as a potent fibrinolysis inhibitor. TAFI gene variations may contribute to plasma TAFI levels and thrombotic risk. DESIGN AND METHODS: We sequenced a 2083-bp region of the

  13. Effect of fibrinolysis inhibitors on survival time of irradiated rats

    International Nuclear Information System (INIS)

    Smok, W.

    1988-01-01

    The possibilities of alleviation of the gastrointestinal syndrome of acute radiation sickness by modification of haemorrhagic diathesis using EACA and traskolan were studied. A significant prolongation of the mean survival time was obtained in the irradiated rats treated with EACA. 7 tabs., 10 refs. (author)

  14. Thrombin Avtivable Fibrinolysis Inhibitor in Venous and Arterial Thrombosis

    NARCIS (Netherlands)

    E.L.E. de Bruijne

    2011-01-01

    textabstractVenous and arterial thromboses are major causes of morbidity and mortality. Venous thrombosis is the result of pathological occlusive clot formation in the veins. It occurs mainly in the deep veins of the leg (deep vein thrombosis), from which parts of the clot frequently embolize to the

  15. Smart activatable and traceable dual-prodrug for image-guided combination photodynamic and chemo-therapy.

    Science.gov (United States)

    Hu, Fang; Yuan, Youyong; Mao, Duo; Wu, Wenbo; Liu, Bin

    2017-11-01

    Activatable photosensitizers (PSs) and chemo-prodrugs are highly desirable for anti-cancer therapy to reduce systemic toxicity. However, it is difficult to integrate both together into a molecular probe for combination therapy due to the complexity of introducing PS, singlet oxygen quencher, chemo-drug, chemo-drug inhibitor and active linker at the same time. To realize activatable PS and chemo-prodrug combination therapy, we develop a smart therapeutic platform in which the chemo-prodrug serves as the singlet oxygen quencher for the PS. Specifically, the photosensitizing activity and fluorescence of the PS (TPEPY-SH) are blocked by the chemo-prodrug (Mitomycin C, MMC) in the probe. Meanwhile, the cytotoxicity of MMC is also inhibited by the electron-withdrawing acyl at the nitrogen position next to the linker. Upon glutathione activation, TPEPY-S-MMC can simultaneously release active PS and MMC for combination therapy. The restored fluorescence of TPEPY-SH is also used to report the activation for both PS and MMC as well as to guide the photodynamic therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Thrombin-Activatable Microbubbles as Potential Ultrasound Contrast Agents for the Detection of Acute Thrombosis.

    Science.gov (United States)

    Lux, Jacques; Vezeridis, Alexander M; Hoyt, Kenneth; Adams, Stephen R; Armstrong, Amanda M; Sirsi, Shashank R; Mattrey, Robert F

    2017-11-01

    Acute deep vein thrombosis (DVT) is the formation of a blood clot in the deep veins of the body that can lead to fatal pulmonary embolism. Acute DVT is difficult to distinguish from chronic DVT by ultrasound (US), the imaging modality of choice, and is therefore treated aggressively with anticoagulants, which can lead to internal bleeding. Here we demonstrate that conjugating perfluorobutane-filled (PFB-filled) microbubbles (MBs) with thrombin-sensitive activatable cell-penetrating peptides (ACPPs) could lead to the development of contrast agents that detect acute thrombosis with US imaging. Successful conjugation of ACPP to PFB-filled MBs was confirmed by fluorescence microscopy and flow cytometry. Fluorescein-labeled ACPP was used to evaluate the efficiency of thrombin-triggered cleavage by measuring the mean fluorescence intensity of ACPP-labeled MBs (ACPP-MBs) before and after incubation at 37 °C with thrombin. Lastly, control MBs and ACPP-MBs were infused through a tube containing a clot, and US contrast enhancement was measured with or without the presence of a thrombin inhibitor after washing the clot with saline. With thrombin activity, 91.7 ± 14.2% of the signal was retained after ACPP-MB infusion and washing, whereas only 16.7 ± 4% of the signal was retained when infusing ACPP-MBs in the presence of hirudin, a potent thrombin inhibitor.

  17. Changes of coagulation and fibrinolysis in middle-old aged patients with nonvalvular atrial fibrillation

    International Nuclear Information System (INIS)

    Li Xi; Xie Ying; Zhang Weijun; Zhao Ruixiang; Peng Xinjie; Zhang Wen; Zhang Yan; Cheng Xiuqin; Wang Longhua; Guo Yonghe; Zhou Yujie; Wen Shaojun; Liu Jielin

    2008-01-01

    Objective: To evaluate the changes of coagulation and fibrinolysis function in the middle-old aged patients with nonvalvular atrial fibrillation. Methods: The levels of D-Dimer and tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) were detected in 92 middle-aged patients with nonvalvular atrial fibrillation (AF group) and 60 patients with sinus rhythm (control group) by immune turbidimetry and enzyme linked immunoadsorbent assay (ELISA). Univariate analysis was used to determine the differences between two groups, and covariance analysis was used to determine the factors which might affect coagulation and fibrinolysis indexes. Results: 1)The plasma levels of D-Dimer [(0.16±0.10) mg·L -1 ] and t-PA [(42.58± 30.28) μg·L -1 ] and PAI-1 [(86.03 ± 21.43) μg·L -1 ] in AF group were significantly higher than those in the control group [(0.10 ± 0.08) mg·L -1 , (26.02±13.84) μg·L -1 , (64.94±24.35) μg·L -1 ] (P<0.05 or P <0.001). The ratio of PAI-1/t-PA in AF group was higher than that in control group slightly. 2) After adjustment of the factors which included sex, age and plasma creatinine, uric acid, blood sugar, triglyceride and cholesterol, the levels of D-Dimer (P=0.047), t-PA (P=0.264) and PAI-1 (P=0.001) in AF group were higher than those in the control group. Conclusion: The middle-old aged patients with nonvalvular atrial fibrillation lose their balance of coagulation and fibrinolysis in the state of hypercoagulated and hypofibrinolysis. (authors)

  18. Warfarin and fibrinolysis - a challenging combination: an observational cohort study

    Directory of Open Access Journals (Sweden)

    Luurila Harri

    2011-04-01

    Full Text Available Abstract Background Patients presenting with ST-segment elevation myocardial infarction (STEMI frequently use warfarin. Fibrinolytic agents and warfarin both increase bleeding risk, but only a few studies have been published concerning the bleeding risk of warfarin-prescribed patients receiving fibrinolysis. The objective of this study was to define the prevalence for intracranial haemorrhage (ICH or major bleeding in patients on warfarin treatment receiving pre-hospital fibrinolysis. Methods This was an observational cohort study. Data for this retrospective case series were collected in Helsinki Emergency Medical Service catchment area from 1.1.1997 to 30.6.2010. All warfarin patients with suspected ST-segment elevation myocardial infarction (STEMI, who received pre-hospital fibrinolysis, were included. Bleeding complications were detected from Medical Records and classified as ICH, major or minor bleeding. Results Thirty-six warfarin patients received fibrinolysis during the study period. Fourteen patients had bleeding complications. One (3%, 95% CI 0-15% patient had ICH, six (17%, 95% CI 7-32% had major and seven (19%, 95% CI 9-35% had minor bleeding. The only fatal bleeding occurred in a patient with ICH. Patients' age, fibrinolytic agent used or aspirin use did not predispose to bleeding complications. High International Normalized Ratio (INR seemed to predispose to bleedings with values over 3, but no statistically significant difference was found. Conclusions Bleedings occur frequently in warfarin patients treated with fibrinolysis in the real world setting, but they are rarely fatal.

  19. Hyperthermic Fibrinolysis with rt-PA: In Vitro Results

    International Nuclear Information System (INIS)

    Schwarzenberg, Helmut; Mueller-Huelsbeck, Stefan; Brossman, Joachim; Christian Glueer, Claus; Bruhn, Hans Dieter; Heller, Martin

    1998-01-01

    Purpose: To investigate the influence of hyperthermia up to 45 deg. C on fibrinolysis with recombinant tissue-type plasminogen activator (rt-PA). Methods: Standardized fibrin clots were incubated in a water bath for 5 hr with either rt-PA (test group) or 0.9% sodium chloride (control group) and blood plasma at temperatures of 30-45 deg. C. Concentrations of D-dimer and time to complete clot lysis were measured.Results: The activity of fibrinolysis with rt-PA rose with increasing temperature: time to lysis approximately halved from 30 deg. C to 40 deg. C and the concentration of D-dimer tripled. In the control group clot size did not change.Conclusions: Activity of rt-PA-induced fibrinolysis rises distinctly with higher temperatures. Since even healthy subjects show a physiologic decline in body temperature in the extremities, in patients with occlusive arterial disease decreased activity of fibrinolysis with rt-PA can be expected. Controlled hyperthermia may improve fibrinolysis with rt-PA and should be investigated in vivo

  20. Lack of TAFI increases brain damage and microparticle generation after thrombolytic therapy in ischemic stroke

    NARCIS (Netherlands)

    Orbe, J.; Alexandru, N.; Roncal, C.; Belzunce, M.; Bibiot, P.; Rodriguez, J. A.; Meijers, J. C. M.; Georgescu, A.; Paramo, J. A.

    2015-01-01

    Background: Thrombin-activatable fibrinolysis inhibitor (TAFI) plays an important role in coagulation and fibrinolysis. Whereas TAFI deficiency may lead to a haemorrhagic tendency, data from TAFI knockout mice (TAFI-/-) are controversial and no differences have been reported in these animals after

  1. Inhibitors

    Science.gov (United States)

    ... JM, and the Hemophilia Inhibitor Research Study Investigators. Validation of Nijmegen-Bethesda assay modifications to allow inhibitor ... webinars on blood disorders Language: English (US) Español (Spanish) File Formats Help: How do I view different ...

  2. Biomarkers of coagulation, fibrinolysis, endothelial function, and inflammation in arterialized venous blood

    DEFF Research Database (Denmark)

    Gram, Anne Sofie; Skov, Jane; Ploug, Thorkil

    2014-01-01

    Effects of venous blood arterialization on cardiovascular risk markers are still unknown. We evaluated biomarkers of inflammation, coagulation, fibrinolysis, and endothelial function in arterialized compared with regular venous blood. Cubital venipunctures were obtained from 10 healthy volunteers....... Arterialization was generated by 10 min heating of the contralateral hand. Concentrations of albumin, C-reactive protein (CRP), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor type 1 (PAI-1), and von Willebrand factor (vWF) were measured by validated assays. Concentrations of albumin......, CRP, and vWF were significantly lower in arterialized than in venous blood (albumin: 43.8 g/l and 44.8 g/l, P = 0.02). Differences in CRP and vWF became insignificant after adjusting for albumin. The endogenous thrombin potential (ETP) was significantly higher in arterialized than in venous blood...

  3. Activated protein C plays no major roles in the inhibition of coagulation or increased fibrinolysis in acute coagulopathy of trauma-shock: a systematic review.

    Science.gov (United States)

    Gando, Satoshi; Mayumi, Toshihiko; Ukai, Tomohiko

    2018-01-01

    The pathophysiological mechanisms of acute coagulopathy of trauma-shock (ACOTS) are reported to include activated protein C-mediated suppression of thrombin generation via the proteolytic inactivation of activated Factor V (FVa) and FVIIIa; an increased fibrinolysis via neutralization of plasminogen activator inhibitor-1 (PAI-1) by activated protein C. The aims of this study are to review the evidences for the role of activated protein C in thrombin generation and fibrinolysis and to validate the diagnosis of ACOTS based on the activated protein C dynamics. We conducted systematic literature search (2007-2017) using PubMed, the Cochrane Database of Systematic Reviews (CDSR), and the Cochrane Central Register of Controlled Trials (CENTRAL). Clinical studies on trauma that measured activated protein C or the circulating levels of activated protein C-related coagulation and fibrinolysis markers were included in our study. Out of 7613 studies, 17 clinical studies met the inclusion criteria. The levels of activated protein C in ACOTS were inconsistently decreased, showed no change, or were increased in comparison to the control groups. Irrespective of the activated protein C levels, thrombin generation was always preserved or highly elevated. There was no report on the activated protein C-mediated neutralization of PAI-1 with increased fibrinolysis. No included studies used unified diagnostic criteria to diagnose ACOTS and those studies also used different terms to refer to the condition known as ACOTS. None of the studies showed direct cause and effect relationships between activated protein C and the suppression of coagulation and increased fibrinolysis. No definitive diagnostic criteria or unified terminology have been established for ACOTS based on the activated protein C dynamics.

  4. From fibrinolysis to the plasminogen-plasmin system and beyond: a remarkable growth of knowledge, with personal observations on the history of fibrinolysis.

    Science.gov (United States)

    Kwaan, Hau C

    2014-07-01

    Great advances have been made in our understanding of the fibrinolytic system from the initial discovery of proteolysis of fibrin by plasmin to the multifaceted and complex role of the plasminogen-plasmin (P-P) system. We now know that the P-P system is composed of several serine proteases and their inhibitors (serpins). This system is involved in many physiological functions, including embryogenesis, cell migration, and wound healing. They also play an important role in the pathogenesis of many diseases, including atherosclerosis, obesity, cancer, and even autoimmune disorders, and neuronal degeneration. Knowledge of their role in cancer enables their use as a prognostic factor. Therapeutic use of various forms of proteases derived from this system has been employed as thrombolytic agents. In addition, small molecules designed to inhibit many of the components of the P-P system are now available for clinical trial, aimed at treatment of these various disorders. The history of such remarkable development of our knowledge on fibrinolysis is reviewed in this article. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  5. The influence of weather on fibrinolysis and fibrinogenolysis. [in human body

    Science.gov (United States)

    Marchenko, V. I.

    1974-01-01

    Analysis of fibrinolysis and fibrinogenolysis indices by month showed an increase in the activity of these processes from winter to summer (1967-1968). At all seasons of the year, fibrinolysis and fibrinogenolysis increase during weather of the cyclonic type with passage of fronts and sharp fluctuations in meteorological factors in the atmosphere.

  6. Fibrinolysis standards: a review of the current status.

    Science.gov (United States)

    Thelwell, C

    2010-07-01

    Biological standards are used to calibrate measurements of components of the fibrinolytic system, either for assigning potency values to therapeutic products, or to determine levels in human plasma as an indicator of thrombotic risk. Traditionally WHO International Standards are calibrated in International Units based on consensus values from collaborative studies. The International Unit is defined by the response activity of a given amount of the standard in a bioassay, independent of the method used. Assay validity is based on the assumption that both standard and test preparation contain the same analyte, and the response in an assay is a true function of this analyte. This principle is reflected in the diversity of source materials used to prepare fibrinolysis standards, which has depended on the contemporary preparations they were employed to measure. With advancing recombinant technology, and improved analytical techniques, a reference system based on reference materials and associated reference methods has been recommended for future fibrinolysis standards. Careful consideration and scientific judgement must however be applied when deciding on an approach to develop a new standard, with decisions based on the suitability of a standard to serve its purpose, and not just to satisfy a metrological ideal. 2010 The International Association for Biologicals. Published by Elsevier Ltd. All rights reserved.

  7. In vivo imaging of membrane type-1 matrix metalloproteinase with a novel activatable near-infrared fluorescence probe.

    Science.gov (United States)

    Shimizu, Yoichi; Temma, Takashi; Hara, Isao; Makino, Akira; Kondo, Naoya; Ozeki, Ei-Ichi; Ono, Masahiro; Saji, Hideo

    2014-08-01

    Membrane type-1 matrix metalloproteinase (MT1-MMP) is a protease activating MMP-2 that mediates cleavage of extracellular matrix components and plays pivotal roles in tumor migration, invasion and metastasis. Because in vivo noninvasive imaging of MT1-MMP would be useful for tumor diagnosis, we developed a novel near-infrared (NIR) fluorescence probe that can be activated following interaction with MT1-MMP in vivo. MT1-hIC7L is an activatable fluorescence probe comprised of anti-MT1-MMP monoclonal antibodies conjugated to self-assembling polymer micelles that encapsulate NIR dyes (IC7-1, λem : 858 nm) at concentrations sufficient to cause fluorescence self-quenching. In aqueous buffer, MT1-hIC7L fluorescence was suppressed to background levels and increased approximately 35.5-fold in the presence of detergent. Cellular uptake experiments revealed that in MT1-MMP positive C6 glioma cells, MT1-hIC7L showed significantly higher fluorescence that increased with time as compared to hIC7L, a negative control probe lacking the anti-MT1-MMP monoclonal antibody. In MT1-MMP negative MCF-7 breast adenocarcinoma cells, both MT1-hIC7L and hIC7L showed no obvious fluorescence. In addition, the fluorescence intensity of C6 cells treated with MT1-hIC7L was suppressed by pre-treatment with an MT1-MMP endocytosis inhibitor (P imaging using probes intravenously administered to tumor-bearing mice showed that MT1-hIC7L specifically visualized C6 tumors (tumor-to-background ratios: 3.8 ± 0.3 [MT1-hIC7L] vs 3.1 ± 0.2 [hIC7L] 48 h after administration, P fluorescence in MCF-7 tumors. Together, these results show that MT1-hIC7L would be a potential activatable NIR probe for specifically detecting MT1-MMP-expressing tumors. © 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

  8. Superselective intra-arterial fibrinolysis for acute cerebral ischemic infarct : usefulness of diffusion weighted MR imaging

    International Nuclear Information System (INIS)

    Byun, Woo Mok; Lee, Se Jin; Kim, Yong Sun; Han, Gun Soo; Bae, Won Kyong

    1999-01-01

    To evaluate the efficacy of superselective intra-arterial fibrinolysis for acute cerebral stroke and the usefulness of pre-and postfibrinolysis diffusion-weighted MRI (DWI). In 41 patients with acute ischemic stroke whose treatment involved intra-arterial fibrinolysis, the occlusion site, degree of recanalization, and clinical results were compared. In 12 patients, diffusion weighted MRI was performed before fibrinolysis, and eight of these also underwent diffusion-weighted MRI after fibrinolysis. Using diffusion-weighted MRI, neurological outcomes were compared with signal intensity ratio (SIR, or the average signal intensity within the region of interest divided by that in the contralateral, nonischemic, homologous region). Twenty patients showed complete recanalization, nine partial recanalization, and in twelve there was no recanalization. Fourteen patients (34%) improved neurologically. No relationship existed between occlusion sites, degree of recanalization, and clinical outcome. Among 12 patients who underwent DWI before fibrinolysis, complete recanalization was noted in eight. Neurological improvement was seen in four patients with low SIR( 1.7), neurological outcome was poor despite complete recanalization. Although superselective intra-arterial fibrinolysis for acute cerebral stroke is a good therapeutic method for recanalization, the clinical outcome can be disappointing. We therefore suggest that in cases of acute cerebral ischemic infaret, SIR-as seen on DWI-might be useful for predicting the benefits of recanalization. In such cases, further investigation of the use of DWI prior to fibrinolysis is therefore needed

  9. Activation of Coagulation and Fibrinolysis in Acute Respiratory Distress Syndrome: a Prospective Pilot Study

    Directory of Open Access Journals (Sweden)

    Agnese Ozolina

    2016-11-01

    Full Text Available Introduction: Coagulation and fibrinolysis remain sparsely addressed with regards to acute respiratory distress syndrome (ARDS. We hypothesized that ARDS development might be associated with changes in plasma coagulation and fibrinolysis. Our aim was to investigate the relationships between ARDS diagnosis and plasma concentrations of tissue factor (TF, tissue plasminogen activator (t-PA and plasminogen activator inhibitor-1 (PAI-1 in mechanically ventilated patients at increased risk of developing ARDS. Materials and Methods: We performed an ethically approved prospective observational pilot study. Inclusion criteria: patients with PaO2/FiO2 < 300 mmHg admitted to the intensive care unit (ICU for mechanical ventilation for 24 hours, or more, because of one or more disease conditions associated with increased risk of developing ARDS. Exclusion criteria: age below 18 years; cardiac disease. We sampled plasma prospectively and compared patients who developed ARDS with those who did not using descriptive statistics and chi-square analysis of baseline demographical and clinical data. We also analyzed plasma concentrations of TF, t-PA and PAI-1 at inclusion (T0 and on third (T3 and seventh day (T7 of the ICU stay with non-parametric statistics inclusive their sensitivity and specificity associated with the development of ARDS using receiver operating characteristic (ROC curve analysis. Statistical significance: p < 0.05.Results: Of 24 patients at risk, six developed mild ARDS and four of each moderate or severe ARDS, respectively, 3 ± 2 (Mean ± SD days after inclusion. Median plasma concentrations of TF and PAI-1 were significantly higher at T7 in patients with ARDS, as compared to non-ARDS. Simultaneously, we found moderate correlations between plasma concentrations of TF and PAI-1, TF and PaO2/FiO2 and PEEP and TF. TF plasma concentration was associated with ARDS with 71% sensitivity and 100% specificity, a cut off level of 145 pg/ml and AUC 0

  10. Cascading of molecular logic gates for advanced functions: a self-reporting, activatable photosensitizer.

    Science.gov (United States)

    Erbas-Cakmak, Sundus; Akkaya, Engin U

    2013-10-18

    Logical progress: Independent molecular logic gates have been designed and characterized. Then, the individual molecular logic gates were coerced to work together within a micelle. Information relay between the two logic gates was achieved through the intermediacy of singlet oxygen. Working together, these concatenated logic gates result in a self-reporting and activatable photosensitizer. GSH=glutathione. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. The effects of ropivacaine hydrochloride on coagulation and fibrinolysis. An assessment using thromboelastography.

    LENUS (Irish Health Repository)

    Porter, J M

    2012-02-03

    Amide local anaesthetics impair coagulation by inhibition of platelet function and enhanced fibrinolysis. The potential therefore exists that the presence of amide local anaesthetics in the epidural space could contribute to the therapeutic failure of an epidural autologous blood patch. Ropivacaine is an aminoamide local anaesthetic increasingly used for epidural analgesia and anaesthesia, particularly in obstetric practice. This study was undertaken to investigate whether concentrations of ropivacaine in blood, which could occur clinically in the epidural space, alter coagulation or fibrinolysis. Thromboelastography was used to assess clotting and fibrinolysis of blood to which ropivacaine had been added. Although modest alterations in maximum amplitude, coagulation time and alpha angle were observed, the effect of ropivacaine on clotting and fibrinolysis was not clinically significant. We conclude that it is unlikely that the presence of ropivacaine in the epidural space would reduce the efficacy of an early or prophylactic epidural blood patch.

  12. Plasma Fibrinolysis Parameters in Smokers and Non-smokers of the Ludwigshafen Risk and Cardiovascular Health (LURIC) Study.

    Science.gov (United States)

    Delgado, Graciela E; Siekmeier, Rüdiger; Krämer, Bernhard K; März, Winfried; Kleber, Marcus E

    2015-01-01

    Cardiovascular diseases (CVD) are an important cause of morbidity and mortality worldwide. Parameters of coagulation and fibrinolysis are risk factors of CVD and might be affected by cigarette smoking. Aim of our study was to analyze the effect of cigarette smoking on parameters of fibrinolysis in active smokers (AS) and life-time non-smokers (NS) of the Ludwigshafen Risk and Cardiovascular Health (LURIC) Study as well as the use of these parameters for risk prediction. We determined plasminogen activator inhibitor-1 (PAI-1), tissue plasminogen activator antigen (t-PA), protein C activity, and D-dimers in 3,316 LURIC patients. Smoking status was assessed by a questionnaire and measurement of plasma cotinine concentration. Cox regression was used to assess the effect of parameters on mortality. We found that of the 3,316 LURIC patients 777 were AS and 1,178 NS. Within the observation period of 10 years (median) 221 AS and 302 NS died. In male AS vs. NS, PAI-1 (19.0 (10.0-35.0) vs. 15.0 (9.0-29.0) U/ml; p=0.026) and t-PA antigen (12.7 (9.6-16.3) vs. 11.6 (8.9-14.6) μg/l; p=0.020) were slightly increased, while t-PA activity was slightly decreased (0.63 (0.30-1.05) vs. 0.68 (0.42-1.10) U/l; p=0.005). In female AS vs. NS, t-PA antigen (10.5 (8.3-13.9) vs. 11.5 (8.8-15.0) μg/l; p=0.025) and protein C (108.0±24.1% vs. 118.0±25.7%; p=0.004) were decreased. All parameters except for protein C were predictive for mortality in AS. Fully adjusted hazard ratios (95% CI) were 1.14 (1.04-1.25), 1.19 (1.06-1.34), and 1.29 (1.11-1.49) per 1SD increase for D-dimer, t-PA, and PAI-1, respectively. Including fibrinolysis parameters in risk prediction models for mortality improved the area-under-the-curve (AUC) significantly compared with the conventional risk factors. In conclusion, we found alterations in the fibrinolytic system in smokers, which were more pronounced in male AS. PAI-1, t-PA and D-dimers were significant predictors of mortality in AS in LURIC and should be

  13. Physical determinants of fibrinolysis in single fibrin fibers.

    Directory of Open Access Journals (Sweden)

    Igal Bucay

    Full Text Available Fibrin fibers form the structural backbone of blood clots; fibrinolysis is the process in which plasmin digests fibrin fibers, effectively regulating the size and duration of a clot. To understand blood clot dissolution, the influence of clot structure and fiber properties must be separated from the effects of enzyme kinetics and perfusion rates into clots. Using an inverted optical microscope and fluorescently-labeled fibers suspended between micropatterned ridges, we have directly measured the lysis of individual fibrin fibers. We found that during lysis 64 ± 6% of fibers were transected at one point, but 29 ± 3% of fibers increase in length rather than dissolving or being transected. Thrombin and plasmin dose-response experiments showed that the elongation behavior was independent of plasmin concentration, but was instead dependent on the concentration of thrombin used during fiber polymerization, which correlated inversely with fiber diameter. Thinner fibers were more likely to lyse, while fibers greater than 200 ± 30 nm in diameter were more likely to elongate. Because lysis rates were greatly reduced in elongated fibers, we hypothesize that plasmin activity depends on fiber strain. Using polymer physics- and continuum mechanics-based mathematical models, we show that fibers polymerize in a strained state and that thicker fibers lose their prestrain more rapidly than thinner fibers during lysis, which may explain why thick fibers elongate and thin fibers lyse. These results highlight how subtle differences in the diameter and prestrain of fibers could lead to dramatically different lytic susceptibilities.

  14. [Reversion of overweight and obesity in Vilafranca del Penedès child population: ACTIVA'T Program (2012)].

    Science.gov (United States)

    Bibiloni, Maria Del Mar; Fernández-Blanco, Jordi; Pujol-Plana, Noemí; Surià Sonet, Sònia; Pujol-Puyané, Maria Cèlia; Mercadé Fuentes, Sílvia; Ojer Fernández de Soto, Laura; Tur, Josep A

    2017-11-20

    To assess a 6-month nutritional and physical activity intervention program on the nutritional status of overweight or obese and not very active 8-14 years old children by means of a controlled pre-post design (ACTIVA'T program). Pre-post study in 8-14 years old overweight or obese and low active children from Vilafranca del Penedès (Barcelona, Spain) randomized in control group (n = 51, 47.1% girls, nutritional intervention and ≤3h/wk physical activity) and ACTIVA'T group (n = 45, 37.8% girls, nutritional and physical activity ≥5h/wk intervention). Body mass index, waist/height index, and diet quality by means of KIDMED test at the beginning and at the end of the program were assessed. During the intervention, each participant was accompanied by a relative (father or mother) who performed the same activities as the children. Dietary recommendations have positively changed the habits of both ACTIVA'T and control group. The reversion in the prevalence of overweight and obesity was 93.8% and 58.6%, respectively, in the ACTIVA'T group, compared to 25.0% and 35.8% in the control group. Abdominal obesity was decreased from 42.2% to 17.8% in the ACTIVA'T group and from 47.1% to 27.5% in the control group. The program ACTIVA'T (nutritional education and physical activity promotion) improves the quality of diet and reverses the prevalence of overweight and obesity in the underactive child population. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. An ibuprofen-antagonized plasmin inhibitor released by human endothelial cells.

    Science.gov (United States)

    Rockwell, W B; Ehrlich, H P

    1991-02-01

    Serum-free culture medium harvested from endothelial cell monolayer cultures derived from human scars and dermis was examined for inhibition of fibrinolysis using a fibrin plate assay. Human cultured fibroblasts and smooth muscle cells did not produce any detectable inhibitory activity. The inhibitor is spontaneously released from the cultured endothelial cells over time. In the fibrin plate assay of plasmin-induced fibrinolysis, one nonsteroidal antiinflammatory (NSAI) drug, ibuprofen, was demonstrated to antagonize the inhibition of fibrinolysis. The antagonistic activity of ibuprofen appears unrelated to its NSAI drug activity because other NSAI drugs such as indomethacin and tolmetin have minimal antagonistic activity. Heating the cultured endothelial cells to 42 degrees C stimulates greater release of the inhibitor in a shorter period of time. This plasmin inhibitor, which is produced by endothelial cells, may contribute to postburn vascular occlusion, leading to secondary progressive necrosis in burn-traumatized patients.

  16. Sensitive and selective tumor imaging with novel and highly activatable fluorescence probes

    International Nuclear Information System (INIS)

    Urano, Yasuteru

    2008-01-01

    Selective and sensitive tumor imaging in vivo is one of the most requested methodologies in medical sciences. Although several imaging modalities have been developed including positron emission tomography (PET) and magnetic resonance (MR) imaging for the detection of tumors, none of these modalities can activate the signals upon being accumulated or uptaken to tumor sites. Among these modalities, only optical fluorescence imaging has a marked advantage, that is, their signals can be dramatically increased upon detecting some biological features. In this short review, I will introduce some recent strategies for activatable optical fluorescence imaging of tumors, and discuss their advantages over other modalities. (author)

  17. The smoker's paradox after successful fibrinolysis: reduced risk of reocclusion but no improved long-term cardiac outcome.

    NARCIS (Netherlands)

    Kievit, P.C.; Brouwer, M.A.; Veen, G.; Aengevaeren, W.R.M.; Verheugt, F.W.A.

    2009-01-01

    BACKGROUND: In smokers treated with fibrinolysis for ST-elevation myocardial infarction (STEMI) a paradoxical beneficial short-term outcome has been reported. This was attributed to favorable clinical and angiographic baseline variables and a better response to fibrinolysis. During follow-up infarct

  18. Factors contributing to the disturbance of coagulation and fibrinolysis in dengue virus infection

    Directory of Open Access Journals (Sweden)

    Yung-Chun Chuang

    2013-01-01

    Full Text Available Hemorrhage is one of the hallmarks of dengue hemorrhagic fever. However, the mechanisms that cause hemorrhage are unclear. In this review we focus on the possible factors that may be involved in the disturbance of coagulation and fibrinolysis during dengue virus (DENV infection. Factors such as autoantibodies and cytokines induced by DENV infection as well as hemostatic molecules expressed on DENV-infected cells, and DENV viral proteins may all contribute to the defect of hemostasis during DENV infection. It is the combination of these viral and host factors that may tilt the balance of coagulation and fibrinolysis toward bleeding in dengue patients.

  19. The role of ACTH and glucocorticoids in nonenzymatic fibrinolysis during immobilization stress in animals

    Science.gov (United States)

    Kudryashov, B. A.; Shapiro, F. B.; Lomovskaya, E. G.; Lyapina, L. A.

    1980-01-01

    The role of the altered hormonal status of an organism in the activation of the anticoagulative system during stress is investigated. The 30 minute immobilization stress was shown to raise significantly the nonenzymatic fibrinolytic activity of blood in rats. Combined with adrenocorticotropin (ACTH) the effect is still greater. Intravenous administration of 0.2 m1 0.01 percent solution of protamine sulphate prevented the nonenzymatic fibrinolysis induced by the stress. Administration of ACTH after protomine sulphate again raised the fibrinolysis. This suggests that ACTH stimulates the release of heparin.

  20. Platelet transfusions reduce fibrinolysis but do not restore platelet function during trauma hemorrhage.

    Science.gov (United States)

    Vulliamy, Paul; Gillespie, Scarlett; Gall, Lewis S; Green, Laura; Brohi, Karim; Davenport, Ross A

    2017-09-01

    Platelets play a critical role in hemostasis with aberrant function implicated in trauma-induced coagulopathy. However, the impact of massive transfusion protocols on platelet function during trauma hemorrhage is unknown. The aim of this study was to characterize the effects of platelet transfusion on platelet aggregation and fibrinolytic markers during hemostatic resuscitation. Trauma patients enrolled into the prospective Activation of Coagulation and Inflammation in Trauma study between January 2008 and November 2015 who received at least four units of packed red blood cells (PRBCs) were included. Blood was drawn in the emergency department within 2 hours of injury and at intervals after every four units of PRBCs transfused. Platelet aggregation was assessed in whole blood with multiple electrode aggregometry. Plasma proteins were quantified by enzyme-linked immunosorbent assay. Of 161 patients who received four or more PRBCs as part of their initial resuscitation, 44 received 8 to 11 units and 28 received 12 units or more. At each timepoint during bleeding, platelet aggregation was similar in patients who had received a platelet transfusion compared with those who had only received other blood products (p > 0.05 for all timepoints). Platelet transfusion during the four PRBC intervals was associated with a decrease in maximum lysis on rotational thromboelastometry (start of interval, 6% [2-12] vs. end of interval, 2% [0-5]; p = 0.001), an increase in plasminogen activator inhibitor-1 (start of interval, 35.9 ± 14.9 vs. end of interval, 66.7 ± 22.0; p = 0.007) and a decrease in tissue plasminogen activator (start of interval, 26.2 ± 10.5 vs. end of interval, 19.0 +/- 5.1; p = 0.04). No statistically significant changes in these parameters occurred in intervals which did not contain platelets. Current hemostatic resuscitation strategies do not appear to restore platelet aggregation during active hemorrhage. However, stored platelets may attenuate fibrinolysis

  1. An eco-friendly in situ activatable antibiotic via cucurbit[8]uril-mediated supramolecular crosslinking of branched polyethylenimine.

    Science.gov (United States)

    Li, Shengke; Jiang, Nan; Zhao, Wenxuan; Ding, Yuan-Fu; Zheng, Ying; Wang, Lian-Hui; Zheng, Jun; Wang, Ruibing

    2017-05-30

    We report an unprecedented, eco-friendly, in situ activatable model antibiotic, phenylalanyl-polyethylenimine (PhePEI), to potentially diminish antibiotic pollution of the environment and associated antibiotic resistance. The inactive PhePEI can be reversibly activated upon supramolecular crosslinking by cucurbit[8]uril, conferring potent antibacterial activity.

  2. Plasmin-driven fibrinolysis facilitates skin tumor growth in a gender-dependent manner

    DEFF Research Database (Denmark)

    Hald, Andreas; Eickhardt, Hanne; Maerkedahl, Rasmus Baadsgaard

    2012-01-01

    deficiency was due to thrombosis and lost patency of the tumor vasculature, resulting in tumor necrosis. The connection between plasmin-dependent fibrinolysis, vascular patency, and tumor growth was further substantiated as the effect of plasminogen deficiency on tumor growth could be reverted...

  3. A novel serine protease secreted by medicinal maggots enhances plasminogen activator-induced fibrinolysis

    DEFF Research Database (Denmark)

    van der Plas, Mariena J A; Andersen, Anders S; Nazir, Sheresma

    2014-01-01

    Maggots of the blowfly Lucilia sericata are used for the treatment of chronic wounds. As haemostatic processes play an important role in wound healing, this study focused on the effects of maggot secretions on coagulation and fibrinolysis. The results showed that maggot secretions enhance plasmin...

  4. The effect of erythropoietin on platelet function and fibrinolysis in chronic renal failure

    DEFF Research Database (Denmark)

    Stenver, Doris Irene; Jeppesen, L; Nielsen, B

    1994-01-01

    The influence of erythropoietin therapy on platelet function and fibrinolysis was evaluated in 12 anemic hemodialysis patients. Six months of therapy with human erythropoietin (50 to 80 IU/kg initially) raised the hemoglobin level to 10.8 g/dl but did not increase platelet activity in vivo as mea...

  5. Preconcentration method using an activatable yield tracer for neutron activation analysis

    International Nuclear Information System (INIS)

    Tsukada, Masamichi; Yamamoto, Daijiro; Endo, Kazutoyo; Nakahara, Hiromichi

    1991-01-01

    Previously, the use of an enriched stable isotope as an activatable yield tracer in preconcentration steps has been tested by use of commercially available enriched 116 Cd and 156 Dy for biological standard reference materials. In the present work, this method has been further applied to the determination of lanthanoid contents in various kinds of samples: one coal fly-ash, three Japanese standard rocks, and eight standard soils. Samples were decomposed by alkali fusion in the preconcentration step. Thirteen elements were determined for coal fly-ash and soil samples, and 14 elements for rocks. The data obtained for coal fly-ash and standard rocks are compared with the data reported in literature. The data for soil samples have been newly determined in the present work. The ordinary instrumental neutron activation analysis and radiochemical neutron activation analysis were also performed to confirm the accuracy and usefulness of the present method. (author) 10 refs.; 4 tabs

  6. Use of radioactive and neutron-activatable tracers to determine effective hydrogeologic parameters

    International Nuclear Information System (INIS)

    Yu, C.; Jester, W.A.; Jarrett, A.R.

    1985-01-01

    The migration of nuclides in a geologic medium is controlled by the hydrogeologic parameters of the medium such as the dispersion coefficient, pore water velocity, retardation factor, degradation rate, mass transfer coefficient, water content, and fraction of dead-end pores. The breakthrough curve (BTC), which is the graphical relationship between the tracer concentration and the elapsed time since introduction, is an integrated picture of the hydrogeologic parameters that produced the BTC. Both radioactive and neutron-activatable tracers have been used to generate BTCs. The BTC of a 92 Br radioactive tracer generated under saturated conditions in a nonhomogeneous (fractured) soil column is shown. From BTCs, the effective hydrogeologic parameters can be identified if appropriate techniques are applied

  7. The predictive value of markers of fibrinolysis and endothelial dysfunction in the post thrombotic syndrome. A systematic review.

    Science.gov (United States)

    Rabinovich, Anat; Cohen, Jacqueline M; Kahn, Susan R

    2014-06-01

    The post thrombotic syndrome (PTS) develops in 20-40% of deep venous thrombosis (DVT) patients. Risk factors for PTS have not been well elucidated. Identification of risk factors would facilitate individualised risk assessment for PTS. We conducted a systematic review to determine whether biomarkers of fibrinolysis or endothelial dysfunction can predict the risk for PTS among DVT patients. Studies were identified by searching the electronic databases PubMed, EMBASE, Scopus and Web of science. We included studies published between 1990 and 2013, measured biomarker levels in adult DVT patients, and reported rates of PTS development. Fourteen studies were included: 11 investigated the association between D-dimer and PTS; three examined fibrinogen; two measured von Willebrand factor; one measured plasminogen activator inhibitor-1; one assessed ADAMTS-13 (A Disintegrin and Metalloprotease with Thrombospondin type 1 repeats) and one measured factor XIII activity. Studies varied with regards to inclusion criteria, definition of PTS, time point and method of biomarker measurement. We were unable to meta-analyse results due to marked clinical heterogeneity. Descriptively, a significant association with PTS was found for D-dimer in four studies and factor XIII in one study. Further prospective research is needed to elucidate whether these markers might be useful to predict PTS development.

  8. Gadolinium-Encapsulating Iron Oxide Nanoprobe as Activatable NMR/MRI Contrast Agent

    Science.gov (United States)

    Santra, Santimukul; Jativa, Samuel D.; Kaittanis, Charalambos; Normand, Guillaume; Grimm, Jan; Perez, J. Manuel

    2012-01-01

    Herein we report a novel gadolinium-encapsulating iron oxide nanoparticle-based activatable NMR/MRI nanoprobe. In our design, Gd-DTPA is encapsulated within the polyacrylic acid (PAA) polymer coating of a superparamagnetic iron oxide nanoparticle (IO-PAA) yielding a composite magnetic nanoprobe (IO-PAA-Gd-DTPA) with quenched longitudinal spin-lattice magnetic relaxation (T1). Upon release of the Gd-DTPA complex from the nanoprobe's polymeric coating in acidic media, an increase in the T1 relaxation rate (1/T1) of the composite magnetic nanoprobe was observed, indicating a dequenching of the nanoprobe with a corresponding increase in the T1-weighted MRI signal. When a folate-conjugated nanoprobe was incubated in HeLa cells, a cancer cell line overexpressing folate receptors, an increase in the 1/T1 signal was observed. This result suggests that upon receptor-mediated internalization, the composite magnetic nanoprobe degraded within the cell's lysosome acidic (pH = 5.0) environment, resulting in an intracellular release of Gd-DTPA complex with subsequent T1 activation. No change in T1 was observed when the Gd-DTPA complex was chemically conjugated on the surface of the nanoparticle's polymeric coating or when encapsulated in the polymeric coating of a non-magnetic nanoparticle. These results confirmed that the observed (T1) quenching of the composite magnetic nanoprobe is due to the encapsulation and close proximity of the Gd ion to the nanoparticles superparamagnetic iron oxide (IO) core. In addition, when an anticancer drug (Taxol) was co-encapsulated with the Gd-DTPA within the folate receptor targeting composite magnetic nanoprobe, the T1 activation of the probe coincide with the rate of drug release and corresponding cytotoxic effect in cell culture studies. Taken together, these results suggest that our activatable T1 nanoagent could be of great importance for the detection of acidic tumors and assessment of drug targeting and release by MRI. PMID:22809405

  9. Changes in coagulation-fibrinolysis function in alveolar lavage fluid of endotoxemic dogs after partial removal of peripheral leukocytes

    Directory of Open Access Journals (Sweden)

    Shun-gang ZHOU

    2011-06-01

    Full Text Available Objective To observe the effect of partial removal of peripheral leucocytes on the coagulation-fibrinolysis function of alveolar lavage fluid(ALF in endotoxemic dogs,and explore the influence and mechanisms of activated leucocytes on lung injury in endotoxemic dogs.Methods Thirty male mongrel dogs were involved in present study and randomly divided into 3 groups(10 each: LPS group(group L,sham leukocytapheresis group(group S and leukocytapheresis group(group T.Endotoxemic model was reproduced in group L by administration of LPS(2mg/kg,but the animals did not receive leukocytapheresis.Animals in group T received leukocytapheresis using a continuous-flow blood cell separator 12-14 hours after administration of LPS.Animals in group S received sham leukocytapheresis(the end products were transfused back into the dogs at 12-14 hours after administration of LPS.At 36h after administration of LPS,the lung tissues were harvested to obtain ALF,and the levels of neutrophil elastase(NE,soluble thrombomodulin(sTM,activated protein C(APC and plasminogen activator inhibitor-1(PAI-1 in ALF were determined,the expression of thrombomodulin in lung tissue was observed by immunohistochemical staining,while the routine pathological examination and wet/dry ratio of lung tissue were performed.Results The APC level in ALF was significantly higher,while the NE,sTM and PAI-1 levels in ALF and wet/dry ratio of lung tissue were significantly lower in group T than in group L and group S(P < 0.05.Immunohistochemical examination revealed that the expression of thrombomodulin in lung tissue was higher in group T than in group L and group S.No significant difference was found between group L and group S in the indexes mentioned above.Pathological observation showed the incidence of acute lung injury was significantly lower in group T(2/10 than in group L(7/10 and group S(8/10,P < 0.05.Conclusion Partial removal of peripheral leukocytes may lower the level of NE in ALF

  10. Causal effect of plasminogen activator inhibitor type 1 on coronary heart disease

    NARCIS (Netherlands)

    Song, Ci; Burgess, Stephen; Eicher, John D.; O'Donnell, Christopher J.; Johnson, Andrew D.; Huang, Jie; Sabater-Lleal, Maria; Asselbergs, Folkert W.; Tregouet, David-Alexandre; Shin, So Youn; Ding, Jingzhong; Baumert, Jens; Oudot-Mellakh, Tiphaine; Folkersen, Lasse; Smith, Nicholas L.; Williams, Scott M; Ikram, Mohammad Arfan; Kleber, Marcus E.; Becker, Diane M.; Truong, Vinh; Mychaleckyj, Josyf C.; Tang, Weihong; Yang, Qiong; Sennblad, Bengt; Moore, Jason H; Williams, Frances M.K.; Dehghan, Abbas; Silbernagel, Günther; Schrijvers, Elisabeth M.C.; Smith, Shelly; Karakas, Mahir; Tofler, Geoffrey H.; Silveira, Angela; Navis, Gerjan J.; Lohman, Kurt; Chen, Ming Huei; Peters, Annette; Goel, Anuj; Hopewell, Jemma C.; Chambers, John C.; Saleheen, Danish; Lundmark, Per; Psaty, Bruce M.; Strawbridge, Rona J.; Boehm, Bernhard O.; Carter, Angela M.; Meisinger, Christa; Peden, John F.; Bis, Joshua C.; McKnight, Barbara; Öhrvik, John; Taylor, Kent D.; Franzosi, Maria Grazia; Seedorf, Udo; Collins, Rory; Franco-Cereceda, Anders; Syvänen, Ann-Christine; Goodall, Alison H.; Yanek, Lisa R.; Cushman, Mary; Müller-Nurasyid, Martina; Folsom, Aaron R.; Basu, Saonli; Matijevic, Nena; van Gilst, Wiek H.; Kooner, Jaspal S.; Danesh, John; Clarke, Robert; Meigs, James B; Kathiresan, Sekar; Reilly, Muredach P; Klopp, Norman; Harris, Tamara B.; Winkelmann, Bernhard R.; Grant, Peter J.; Hillege, Hans L.; Watkins, Hugh; Spector, Timothy D; Becker, Lewis C; Tracy, Russell P.; März, Winfried; Uitterlinden, Andre G; Eriksson, Per; Cambien, Francois; Morange, Pierre Emmanuel; Koenig, Wolfgang; Soranzo, Nicole; van der Harst, Pim; Liu, Yongmei; Hamsten, Anders; Ehret, Georg B.; Munroe, Patricia B.; Rice, Kenneth M.; Bochud, Murielle; Chasman, Daniel I.; Smith, Albert V.; Tobin, Martin D; Verwoert, Germaine C; Hwang, Shih-Jen; Pihur, Vasyl; Vollenweider, Peter; O'Reilly, Paul F.; Amin, Najaf; Bragg-Gresham, Jennifer L.; Teumer, Alexander; Glazer, Nicole L.; Launer, Lenore J.; Zhao, Jing Hua; Aulchenko, Yurii S.; Heath, Simon; Sõber, Siim; Parsa, Afshin; Luan, Jian'an; Arora, Pankaj; Zhang, Feng; Lucas, Gavin; Hicks, Andrew A.; Jackson, Anne U.; Tanaka, Toshiko; Wild, Sarah H.; Rudan, Igor; Igl, Wilmar; Milaneschi, Yuri; Parker, Alex N.; Fava, Cristiano; Fox, Ervin R.; Kumari, Meena; Go, Min Jin; Linda Kao, Wen Hong; Sjögren, Marketa; Vinay, D. G.; Alexander, Myriam; Tabara, Yasuharu; Shaw-Hawkins, Sue; Whincup, Peter H.; Shi, Gang; Kuusisto, Johanna; Tayo, Bamidele O.; Seielstad, Mark; Sim, Xueling; Nguyen, Khanh Dung Hoang; Lehtimäki, Terho; Matullo, Giuseppe; Wu, Ying; Gaunt, Tom R.; Onland-Moret, N. Charlotte; Cooper, Matthew N.; Platou, Carl G P; Org, Elin; Hardy, Rebecca; Dahgam, Santosh; Palmen, Jutta; Vitart, Veronique; Braund, Peter S; Kuznetsova, Tatiana; Uiterwaal, Cuno S.P.M.; Adeyemo, Adebowale; Palmas, Walter R.; Campbell, Harry; Ludwig, Barbara; Tomaszewski, Maciej; Tzoulaki, Ioanna; Palmer, Nicholette D.; Aspelund, Thor; Garcia, Melissa; Chang, Yen Pei C.; O'Connell, Jeffrey R.; Steinle, Nanette I.; Grobbee, Diederick E.; Arking, Dan E.; Kardia, Sharon L. R.; Morrison, Alanna C.; Hernandez, Dena G.; Najjar, Samer; McArdle, Wendy L.; Hadley, David; Brown, Morris J; Connell, John M; Hingorani, Aroon D.; Day, Ian N M; Lawlor, Debbie A.; Beilby, John P.; Lawrence, Robert W.; Ongen, Halit; Dreisbach, Albert W; Li, Yali; Young, J. Hunter; Kähönen, Mika; Viikari, Jorma S.; Adair, Linda S.; Lee, Nanette R.; Olden, Matthias; Pattaro, Cristian; Hoffman Bolton, Judith A.; Köttgen, Anna; Bergmann, Sven; Mooser, Vincent; Chaturvedi, Nish; Frayling, Timothy M.; Islam, Muhammad; Jafar, Tazeen H.; Erdmann, Jeanette; Kulkarni, Smita R.; Bornstein, Stefan R.; Grässler, Jürgen; Groop, Leif C.; Voight, Benjamin F; Kettunen, Johannes; Howard, Philip; Taylor, Andrew; Guarrera, Simonetta; Ricceri, Fulvio; Emilsson, Valur; Plump, Andrew; Barroso, Inês; Khaw, Kay Tee; Weder, Alan B.; Hunt, Steven C.; Sun, Yan V.; Bergman, Richard N.; Collins, Francis S.; Bonnycastle, Lori L.; Scott, Laura J; Stringham, Heather M.; Peltonen, Leena; Perola, Markus; Vartiainen, Erkki; Brand, Stefan Martin; Staessen, Jan A.; Wang, Thomas J.; Burton, Paul R.; Artigas, Maria Soler; Dong, Yanbin; Snieder, Harold; Wang, Xiaoling; Zhu, Haidong; Lohman, Kurt; Rudock, Megan E.; Heckbert, Susan R; Wiggins, Kerri L.; Doumatey, Ayo; Shriner, Daniel; Veldre, Gudrun; Viigimaa, Margus; Kinra, Sanjay; Prabhakaran, Dorairaj; Tripathy, Vikal; Langefeld, Carl D.; Rosengren, Annika; Thelle, Dag S.; Corsi, Anna Maria; Singleton, Andrew; Forrester, Terrence; Hilton, Gina; McKenzie, Colin A.; Salako, Tunde; Iwai, Naoharu; Kita, Yoshikuni; Ogihara, Toshio; Ohkubo, Takayoshi; Okamura, Tomonori; Ueshima, Hirotsugu; Umemura, Satoshi; Eyheramendy, Susana; Meitinger, Thomas; Wichmann, H-Erich; Cho, Yoon Shin; Kim, Hyung Lae; Lee, Jong-Young; Scott, James; Sehmi, Joban S.; Zhang, Weihua; Hedblad, Bo; Nilsson, Peter M.; Smith, George Davey; Wong, Andrew; Narisu, Narisu; Stančáková, Alena; Raffel, Leslie J.; Yao, Jie; Schwartz, Stephen M.; Arfan Ikram, M.; Longstreth, W.T. jr.; Mosley, Thomas H; Seshadri, Sudha; Shrine, Nick R.G.; Wain, Louise V.; Morken, Mario A.; Swift, Amy J.; Laitinen, Jaana; Prokopenko, Inga; Zitting, Paavo; Cooper, Jackie A.; Humphries, Steve E.; Rasheed, Asif; Bakker, Stephan J. L.; Janipalli, Charles S.; Mani, K. Radha; Yajnik, Chittaranjan S.; Mattace-Raso, Francesco U.S.; Oostra, Ben A.; Demirkan, Ayse; Isaacs, Aaron; Rivadeneira, Fernando; Lakatta, Edward G; Orru, Marco; Scuteri, Angelo; Ala-Korpela, Mika; Kangas, Antti J.; Lyytikäinen, Leo-Pekka; Soininen, Pasi; Tukiainen, Taru; Würtz, Peter; Ong, Rick Twee Hee; Dörr, Marcus; Kroemer, Heyo K; Völker, Uwe; Völzke, Henry; Galan, Pilar; Hercberg, Serge; Lathrop, Mark; Zelenika, Diana; Deloukas, Panos; Mangino, Massimo; Zhai, Guangju; Meschia, James F.; Nalls, Michael A.; Sharma, Pankaj; Terzic, Janos; Kumar, M. V.Kranthi; Denniff, Matthew; Zukowska-Szczechowska, Ewa; Wagenknecht, Lynne E.; Fowkes, F. Gerald R.; Charchar, Fadi J; Schwarz, Peter E. H.; Hayward, Caroline; Guo, Xiuqing; Rotimi, Charles N.; Bots, Michiel L.; Brand, Eva; Samani, Nilesh J.; Polasek, Ozren; Talmud, Philippa J.; Nyberg, Fredrik; Kuh, Diana; Laan, Maris; Hveem, Kristian; Palmer, Lyle J.; van der Schouw, Yvonne T.; Casas, Juan P.; Mohlke, Karen L.; Vineis, Paolo; Raitakari, Olli T.; Ganesh, Santhi K.; Wong, Tien-Yin; Shyong Tai, E.; Cooper, Richard S.; Laakso, Markku; Rao, Dabeeru C.; Morris, Richard W.; Dominiczak, Anna F.; Kivimaki, Mika; Marmot, Michael G.; Miki, Tetsuro; Chandak, Giriraj R.; Coresh, Josef; Navis, Gerjan J.; Salomaa, Veikko; Han, Bok-Ghee; Zhu, Xiaofeng; Melander, Olle; Ridker, Paul M.; Bandinelli, Stefania; Gyllensten, Ulf B.; Wright, Alan F.; Wilson, James F.; Ferrucci, Luigi; Farrall, Martin; Tuomilehto, Jaakko; Pramstaller, Peter P.; Elosua, Roberto; Sijbrands, Eric J. G.; Altshuler, David; Loos, Ruth J. F.; Gieger, Christian; Meneton, Pierre; Wareham, Nicholas J.; Gudnason, Vilmundur; Rotter, Jerome I.; Rettig, Rainer; Uda, Manuela; Strachan, David P.; Witteman, Jacqueline C M; Hartikainen, Anna-Liisa; Beckmann, Jacques S.; Boerwinkle, Eric; Vasan, Ramachandran S; Boehnke, Michael; Larson, Martin G.; Järvelin, Marjo-Riitta; Abecasis, Gonçalo R.; Chakravarti, Aravinda; Elliott, Paul; Van Duijn, Cornelia M.; Newton-Cheh, Christopher; Levy, Daniel; Caulfield, Mark J.; Johnson, Toby; van der Lugt, Aad; Shuldiner, Alan R.; Hofman, Albert; Kraja, Aldi T.; Uitterlinden, Andre G; Ziegler, Andreas; Newman, Anne B; Schillert, Arne; Oostra, Ben A.; Thorsson, Bolli; Mitchell, Braxton D.; Fox, Caroline S.; White, Charles C.; Ballantyne, Christie; Van Duijn, Cornelia M.; Herrington, David M.; O'Leary, Daniel H.; Siscovick, David S.; Couper, David J; Halperin, Eran; Stoegerer, Eva Maria; Ernst, Florian; Krestin, Gabriel P.; Homuth, Georg; Heiss, Gerardo; Usala, Gianluca; Eiriksdottir, Gudny; Shen, Haiqing; Erich Wichmann, H.; Schmidt, Helena; Borecki, Ingrid B.; Markus, Hugh S.; Witteman, Jacqueline C.; Lüdemann, Jan; Huffman, Jennifer E.; Murabito, Joanne M.; Thiery, Joachim; Seissler, Jochen; Massaro, Joseph M.; Polak, Joseph F.; Cunningham, Julie; North, Kari E.; Petrovic, Katja E; Rice, Kenneth M.; Adrienne Cupples, L.; Bielak, Lawrence F.; Launer, Lenore J.; de Andrade, Mariza; Feitosa, Mary F.; Kavousi, Maryam; Sitzer, Matthias; Oudkerk, Matthijs; Province, Michael A.; Nalls, Michael A.; Franceschini, Nora; Peyser, Patricia A.; Wolf, Philip A.; Zhang, Qunyuan; Wild, Philipp S; Schnabel, Renate B.; D'Agostino, Ralph B.; Chilukoti, Ravi Kumar; Schmidt, Reinhold; Sanna, Serena; Demissie, Serkalem; Sigurdsson, Sigurdur; Blankenberg, Stefan; Bevan, Steve; Elias-Smale, Suzette E.; Zeller, Tanja; Illig, Thomas; Münzel, Thomas; Howard, Timothy D.; Hoffmann, Udo; Schminke, Ulf; Nambi, Vijay; Post, Wendy S.; Rathmann, Wolfgang; Li, Xia; Cheng, Yu Ching

    2017-01-01

    Background--Plasminogen activator inhibitor type 1 (PAI-1) plays an essential role in the fibrinolysis system and thrombosis. Population studies have reported that blood PAI-1 levels are associated with increased risk of coronary heart disease (CHD). However, it is unclear whether the association

  11. Smokers with ST-segment elevation myocardial infarction and short time to treatment have equal effects of PCI and fibrinolysis

    DEFF Research Database (Denmark)

    Rasmussen, Thomas; Kelbæk, Henning Skov; Madsen, Jan Kyst

    2012-01-01

    The purpose of this study was to examine the effect of primary percutaneous coronary intervention (PCI) compared to fibrinolysis in smokers and non-smokers with ST-segment elevation myocardial infarction (STEMI). Smokers seem to have less atherosclerosis but are more prone to thrombotic disease....... Compared to non-smokers, they have higher rates of early, complete reperfusion when treated with fibrinolysis for MI....

  12. Immunoradiometric quantitation of tissue plasminogen activator-related antigen in human plasma: crypticity phenomenon and relationship to plasma fibrinolysis

    International Nuclear Information System (INIS)

    Wun, T.C.; Capuano, A.

    1987-01-01

    A two-site immunoradiometric assay for tissue plasminogen activator (tPA) antigen has been developed using immunoaffinity purified antibody. Various treatments enhanced the detection of tPA antigen in the plasma samples. Maximum detection was obtained by acidification of plasma to pH 4.8 to 6.5 or addition of 0.5 mol/L of L-lysine or L-arginine. Acidification or addition of lysine to plasma is also required for maximum immunoadsorption of plasma tPA antigen on anti-tPA-Ig-sepharose. These results indicate that plasma tPA antigen is partially cryptic to antibody in untreated plasma. The plasma tPA antigen isolated by immunoadsorption of either untreated plasma or acidified plasma on anti-tPA-Ig-sepharose consists mainly of a 100-kd plasminogen activator species as determined by fibrin-agar zymography. The 100-kd activity is possibly a tPA:inhibitor complex. A standardized sample preparation method was conveniently adopted by mixing 3 vol of plasma and 1 vol of 2 mol/L of L-lysine for the assay. Reconstitution and recovery studies showed that the method is specific and permits full detection of both free tPA and tPA:inhibitor complex. The validity of the assay is further supported by the finding that the spontaneous plasma fibrinolysis previously demonstrated to be dependent on plasma tPA antigen is correlated with tPA antigen content. Using the standardized assay, we found that tPA antigen concentrations in 16 blood bank plasmas are equivalent to 3.7 to 20 ng of 60 kd tPA/mL. In all the plasma tested, more than half of the antigen is undetected unless the plasma is treated as described above

  13. Immunoradiometric quantitation of tissue plasminogen activator-related antigen in human plasma: crypticity phenomenon and relationship to plasma fibrinolysis

    Energy Technology Data Exchange (ETDEWEB)

    Wun, T.C.; Capuano, A.

    1987-05-01

    A two-site immunoradiometric assay for tissue plasminogen activator (tPA) antigen has been developed using immunoaffinity purified antibody. Various treatments enhanced the detection of tPA antigen in the plasma samples. Maximum detection was obtained by acidification of plasma to pH 4.8 to 6.5 or addition of 0.5 mol/L of L-lysine or L-arginine. Acidification or addition of lysine to plasma is also required for maximum immunoadsorption of plasma tPA antigen on anti-tPA-Ig-sepharose. These results indicate that plasma tPA antigen is partially cryptic to antibody in untreated plasma. The plasma tPA antigen isolated by immunoadsorption of either untreated plasma or acidified plasma on anti-tPA-Ig-sepharose consists mainly of a 100-kd plasminogen activator species as determined by fibrin-agar zymography. The 100-kd activity is possibly a tPA:inhibitor complex. A standardized sample preparation method was conveniently adopted by mixing 3 vol of plasma and 1 vol of 2 mol/L of L-lysine for the assay. Reconstitution and recovery studies showed that the method is specific and permits full detection of both free tPA and tPA:inhibitor complex. The validity of the assay is further supported by the finding that the spontaneous plasma fibrinolysis previously demonstrated to be dependent on plasma tPA antigen is correlated with tPA antigen content. Using the standardized assay, we found that tPA antigen concentrations in 16 blood bank plasmas are equivalent to 3.7 to 20 ng of 60 kd tPA/mL. In all the plasma tested, more than half of the antigen is undetected unless the plasma is treated as described above.

  14. Reduced platelet-mediated and enhanced leukocyte-mediated fibrinolysis in experimentally induced diabetes in rats

    International Nuclear Information System (INIS)

    Winocour, P.D.; Colwell, J.A.

    1985-01-01

    Studies of fibrinolytic activity in diabetes mellitus have produced conflicting results. This may be a result of methodologic insensitivity or of variable contributions of the different blood components to whole blood fibrinolysis. To explore these two possibilities, the authors used a sensitive solid-phase radiometric assay to examine the fibrinolytic activity of whole blood, platelet-rich plasma, leukocytes, and platelet- and leukocyte-poor plasma prepared from control rats and rats with streptozocin-induced diabetes at various times after induction of diabetes. Fibrinolytic activity of whole blood from diabetic rats after 7 days was significantly reduced, and remained reduced after longer durations of diabetes up to 28 days. Platelet-rich plasma from diabetic rats had decreased fibrinolytic activity, which followed the same time course of changes as in whole blood. The platelet contribution to whole blood fibrinolysis was further reduced in vivo after 14 days of diabetes by a reduced whole blood platelet count. In contrast, fibrinolytic activity of leukocytes from diabetic rats became enhanced after 7 days of diabetes. After 49 days of diabetes, the whole blood leukocyte count was reduced, and in vivo would offset the enhanced activity. Plasma fibrinolytic activity was small compared with that of whole blood and was unaltered in diabetic rats. The authors conclude that altered platelet function contributes to decreased fibrinolytic activity of whole blood in diabetic rats, and that this may be partially offset by enhanced leukocyte-mediated fibrinolysis

  15. Blood coagulation and fibrinolysis of the whole-body irradiated rabbits

    International Nuclear Information System (INIS)

    Hishikawa-Itoh, Youko; Ayakawa, Yoshio; Miyata, Nobuki

    1984-01-01

    To study the effects of irradiation on blood coagulation and fibrinolysis, rabbits were irradiated with 60 Co γ-rays (whole-body: 0, 100, 400, 800, 1200 rads). Clotting time, activity of plasmin and plasminogen, and fibrinogen contents of irradiated rabbit plasma were measured at 4 days before, immediately after, and at 1, 3, 7, 10, and 14 days after irradiation. Both clotting times obtained by addition of (kaolin+phospholipid) which expressed effects on the total intrinsic coagulation system, and by addition of (Ca 2+ ) which expressed effects on the total extrinsic coagulation system, were prolonged with small dose irradiation (100 rads) immediately and 3 days after irradiation. However, with high dose irradiation (400-1200 rads), these clotting times were prolonged 1 day after irradiation. The times of manifestation of irradiation effects on clotting time were different in small and high dose irradiation. Plasmin activity was decreased immediately, 1 day after and recovered 3 days after irradiation. Plasminogen activity was markedly increased in 800 and 1200 rads irradiated groups from 3 days after irradiation. Conversion of plasminogen into plasmin was impaired by irradiation. Fibrinogen contents increased rapidly in all irradiated rabbits except for 100 rads from 1 day after irradiation. These results revealed decreased coagulation and fibrinolysis activities in rabbit blood, irradiation injury of both coagulation and fibrinolysis activation systems, and accumulation of the precursors of fibrin and plasmin (i.e., fibrinogen and plasminogen). (author)

  16. Force-activatable biosensor enables single platelet force mapping directly by fluorescence imaging.

    Science.gov (United States)

    Wang, Yongliang; LeVine, Dana N; Gannon, Margaret; Zhao, Yuanchang; Sarkar, Anwesha; Hoch, Bailey; Wang, Xuefeng

    2018-02-15

    Integrin-transmitted cellular forces are critical for platelet adhesion, activation, aggregation and contraction during hemostasis and thrombosis. Measuring and mapping single platelet forces are desired in both research and clinical applications. Conventional force-to-strain based cell traction force microscopies have low resolution which is not ideal for cellular force mapping in small platelets. To enable platelet force mapping with submicron resolution, we developed a force-activatable biosensor named integrative tension sensor (ITS) which directly converts molecular tensions to fluorescent signals, therefore enabling cellular force mapping directly by fluorescence imaging. With ITS, we mapped cellular forces in single platelets at 0.4µm resolution. We found that platelet force distribution has strong polarization which is sensitive to treatment with the anti-platelet drug tirofiban, suggesting that the ITS force map can report anti-platelet drug efficacy. The ITS also calibrated integrin molecular tensions in platelets and revealed two distinct tension levels: 12-54 piconewton (nominal values) tensions generated during platelet adhesion and tensions above 54 piconewton generated during platelet contraction. Overall, the ITS is a powerful biosensor for the study of platelet mechanobiology, and holds great potential in antithrombotic drug development and assessing platelet activity in health and disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Design of ultrasonically-activatable nanoparticles using low boiling point perfluorocarbons.

    Science.gov (United States)

    Sheeran, Paul S; Luois, Samantha H; Mullin, Lee B; Matsunaga, Terry O; Dayton, Paul A

    2012-04-01

    Recently, an interest has developed in designing biomaterials for medical ultrasonics that can provide the acoustic activity of microbubbles, but with improved stability in vivo and a smaller size distribution for extravascular interrogation. One proposed alternative is the phase-change contrast agent. Phase-change contrast agents (PCCAs) consist of perfluorocarbons (PFCs) that are initially in liquid form, but can then be vaporized with acoustic energy. Crucial parameters for PCCAs include their sensitivity to acoustic energy, their size distribution, and their stability, and this manuscript provides insight into the custom design of PCCAs for balancing these parameters. Specifically, the relationship between size, thermal stability and sensitivity to ultrasound as a function of PFC boiling point and ambient temperature is illustrated. Emulsion stability and sensitivity can be 'tuned' by mixing PFCs in the gaseous state prior to condensation. Novel observations illustrate that stable droplets can be generated from PFCs with extremely low boiling points, such as octafluoropropane (b.p. -36.7 °C), which can be vaporized with acoustic parameters lower than previously observed. Results demonstrate the potential for low boiling point PFCs as a useful new class of compounds for activatable agents, which can be tailored to the desired application. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Implication of Free Fatty Acids in Thrombin Generation and Fibrinolysis in Vascular Inflammation in Zucker Rats and Evolution with Aging

    Directory of Open Access Journals (Sweden)

    Jérémy Lagrange

    2017-11-01

    Full Text Available Background: The metabolic syndrome (MetS and aging are associated with modifications in blood coagulation factors, vascular inflammation, and increased risk of thrombosis.Objectives: Our aim was to determine concomitant changes in thrombin generation in the blood compartment and at the surface of vascular smooth muscle cells (VSMCs and its interplay with adipokines, free fatty acids (FFA, and metalloproteinases (MMPs in obese Zucker rats that share features of the human MetS.Methods: Obese and age-matched lean Zucker rats were compared at 25 and 80 weeks of age. Thrombin generation was assessed by calibrated automated thrombography (CAT.Results: Endogenous thrombin potential (ETP was increased in obese rats independent of platelets and age. Clot half-lysis time was delayed with obesity and age. Interleukin (IL-1β and IL-13 were increased with obesity and age respectively. Addition of exogenous fibrinogen, leptin, linoleic, or palmitic acid increased thrombin generation in plasma whereas adiponectin had an opposite effect. ETP was increased at the surface of VSMCs from obese rats and addition of exogenous palmitic acid further enhanced ETP values. Gelatinase activity was increased in aorta at both ages in obese rats and MMP-2 activity was increased in VSMCs from obese rats.Conclusions: Our study demonstrated in MetS an early prothrombotic phenotype of the blood compartment reinforced by procoagulant properties of dedifferentiated and inflammatory VSMCs. Mechanisms involved (1 increased fibrinogen and impaired fibrinolysis and (2 increased saturated fatty acids responsible for additive procoagulant effects. Whether specifically targeting this hypercoagulability using direct thrombin inhibitors would improve outcome in MetS is worth investigating.

  19. Pathophysiological significance and therapeutic applications of snake venom protease inhibitors.

    Science.gov (United States)

    Thakur, Rupamoni; Mukherjee, Ashis K

    2017-06-01

    Protease inhibitors are important constituents of snake venom and play important roles in the pathophysiology of snakebite. Recently, research on snake venom protease inhibitors has provided valuable information to decipher the molecular details of various biological processes and offer insight for the development of some therapeutically important molecules from snake venom. The process of blood coagulation and fibrinolysis, in addition to affecting platelet function, are well known as the major targets of several snake venom protease inhibitors. This review summarizes the structure-functional aspects of snake venom protease inhibitors that have been described to date. Because diverse biological functions have been demonstrated by protease inhibitors, a comparative overview of their pharmacological and pathophysiological properties is also highlighted. In addition, since most snake venom protease inhibitors are non-toxic on their own, this review evaluates the different roles of individual protease inhibitors that could lead to the identification of drug candidates and diagnostic molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Theranostic Niosomes for Efficient siRNA/microRNA Delivery and Activatable Near-Infrared Fluorescent Tracking of Stem Cells

    DEFF Research Database (Denmark)

    Yang, Chuanxu; Shan, Gao; Song, Ping

    2018-01-01

    RNA interference (RNAi) mediated gene regulation in stem cells offers great potential in regenerative medicine. In this study, we developed a theranostic platform for efficient delivery of small RNAs (siRNA/miRNA) to human mesenchymal stem cells (hMSCs) to promote differentiation, and meanwhile...... OFF/ON activatable fluorescence upon cellular internalization, resulting in efficient NIR labeling and the capability to dynamically monitor stem cells in mice. In addition, iSPN/siRNA achieved simultaneous long-term cell tracking and in vivo gene silencing after implantation in mice. These results...

  1. Exosomes account for vesicle-mediated transcellular transport of activatable phospholipases and prostaglandins[S

    Science.gov (United States)

    Subra, Caroline; Grand, David; Laulagnier, Karine; Stella, Alexandre; Lambeau, Gérard; Paillasse, Michael; De Medina, Philippe; Monsarrat, Bernard; Perret, Bertrand; Silvente-Poirot, Sandrine; Poirot, Marc; Record, Michel

    2010-01-01

    Exosomes are bioactive vesicles released from multivesicular bodies (MVB) by intact cells and participate in intercellular signaling. We investigated the presence of lipid-related proteins and bioactive lipids in RBL-2H3 exosomes. Besides a phospholipid scramblase and a fatty acid binding protein, the exosomes contained the whole set of phospholipases (A2, C, and D) together with interacting proteins such as aldolase A and Hsp 70. They also contained the phospholipase D (PLD) / phosphatidate phosphatase 1 (PAP1) pathway leading to the formation of diglycerides. RBL-2H3 exosomes also carried members of the three phospholipase A2 classes: the calcium-dependent cPLA2-IVA, the calcium-independent iPLA2-VIA, and the secreted sPLA2-IIA and V. Remarkably, almost all members of the Ras GTPase superfamily were present, and incubation of exosomes with GTPγS triggered activation of phospholipase A2 (PLA2)and PLD2. A large panel of free fatty acids, including arachidonic acid (AA) and derivatives such as prostaglandin E2 (PGE2) and 15-deoxy-Δ12,14-prostaglandinJ2 (15-d PGJ2), were detected. We observed that the exosomes were internalized by resting and activated RBL cells and that they accumulated in an endosomal compartment. Endosomal concentrations were in the micromolar range for prostaglandins; i.e., concentrations able to trigger prostaglandin-dependent biological responses. Therefore exosomes are carriers of GTP-activatable phospholipases and lipid mediators from cell to cell. PMID:20424270

  2. A Cancer Cell-Activatable Aptamer-Reporter System for One-Step Assay of Circulating Tumor Cells

    Directory of Open Access Journals (Sweden)

    Zihua Zeng

    2014-01-01

    Full Text Available The current antibody-mediated numeration assays of circulating tumor cells (CTCs require multiple steps and are time-consuming. To overcome these technical limitations, a cancer cell-activatable aptamer-reporter was formulated by conjugating a biomarker-specific aptamer sequence with paired fluorochrome-quencher molecules. In contrast to the antibody probes, the intact aptamer-reporter was optically silent in the absence of cells of interest. However, when used in an assay, the aptamer selectively targeted cancer cells through interaction with a specific surface biomarker, which triggered internalization of the aptamer-reporter and, subsequently, into cell lysosomes. Rapid lysosomal degradation of the aptamer-reporter resulted in separation of the paired fluorochrome-quencher molecules. The released fluorochrome emitted bright fluorescent signals exclusively within the targeted cancer cells, with no background noise in the assay. Thus, the assays could be completed in a single step within minutes. By using this one-step assay, CTCs in whole blood and marrow aspirate samples of patients with lymphoma tumors were selectively highlighted and rapidly detected with no off-target signals from background blood cells. The development of the cancer cell-activatable aptamer-reporter system allows for the possibility of a simple and robust point-of-care test for CTC detection, which is currently unavailable.

  3. Non-invasive In Vivo Fluorescence Optical Imaging of Inflammatory MMP Activity Using an Activatable Fluorescent Imaging Agent.

    Science.gov (United States)

    Schwenck, Johannes; Maier, Florian C; Kneilling, Manfred; Wiehr, Stefan; Fuchs, Kerstin

    2017-05-08

    This paper describes a non-invasive method for imaging matrix metalloproteinases (MMP)-activity by an activatable fluorescent probe, via in vivo fluorescence optical imaging (OI), in two different mouse models of inflammation: a rheumatoid arthritis (RA) and a contact hypersensitivity reaction (CHR) model. Light with a wavelength in the near infrared (NIR) window (650 - 950 nm) allows a deeper tissue penetration and minimal signal absorption compared to wavelengths below 650 nm. The major advantages using fluorescence OI is that it is cheap, fast and easy to implement in different animal models. Activatable fluorescent probes are optically silent in their inactivated states, but become highly fluorescent when activated by a protease. Activated MMPs lead to tissue destruction and play an important role for disease progression in delayed-type hypersensitivity reactions (DTHRs) such as RA and CHR. Furthermore, MMPs are the key proteases for cartilage and bone degradation and are induced by macrophages, fibroblasts and chondrocytes in response to pro-inflammatory cytokines. Here we use a probe that is activated by the key MMPs like MMP-2, -3, -9 and -13 and describe an imaging protocol for near infrared fluorescence OI of MMP activity in RA and control mice 6 days after disease induction as well as in mice with acute (1x challenge) and chronic (5x challenge) CHR on the right ear compared to healthy ears.

  4. Two-photon imaging of formaldehyde in live cells and animals utilizing a lysosome-targetable and acidic pH-activatable fluorescent probe.

    Science.gov (United States)

    Xie, Xilei; Tang, Fuyan; Shangguan, Xiaoyan; Che, Shiyi; Niu, Jinye; Xiao, Yongsheng; Wang, Xu; Tang, Bo

    2017-06-13

    Lyso-TPFP presents lysosomal targetability and an acidic pH-activatable response toward formaldehyde. Thus, it exclusively visualizes lysosomal formaldehyde and is immune against it in neutral cytosol and other organelles. In addition, two-photon fluorescence imaging endows Lyso-TPFP with the capability of in situ tracking formaldehyde in live cells and animals.

  5. Tumor necrosis factor increases the production of plasminogen activator inhibitor in human endothelial cells in vitro and in rats in vivo

    NARCIS (Netherlands)

    Hinsbergh, V.W.M. van; Kooistra, T.; Berg, E.A. van den; Princen, H.M.G.; Fiers, W.; Emeis, J.J.

    1988-01-01

    The vascular endothelium plays an important role in fibrinolysis by producing tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI). The monokine tumor necrosis factor (human recombinant TNF) increased the production of PAI by cultured human endothelial cells from

  6. Is clinical outcome of dengue-virus infections influenced by coagulation and fibrinolysis? A critical review of the evidence.

    NARCIS (Netherlands)

    Mairuhu, A.T.; MacGillavry, M.R.; Setiati, T.E.; Soemantri, A.; Cate, H. ten; Brandjes, D.P.; Gorp, E. van

    2003-01-01

    Despite efforts to elucidate the pathogenesis of dengue fever, the progression into severe disease remains poorly understood. In-vitro findings suggest that coagulopathy and disturbances in fibrinolysis have a pivotal role in the pathophysiology. If disturbances in these processes are predictive of

  7. Activation of coagulation and inhibition of fibrinolysis in the human lung on bronchial instillation of lipoteichoic acid and lipopolysaccharide

    NARCIS (Netherlands)

    Hoogerwerf, Jacobien J.; de Vos, Alex F.; Levi, Marcel; Bresser, Paul; van der Zee, Jaring S.; Draing, Christian; von Aulock, Sonja; van der Poll, Tom

    2009-01-01

    Objective. Pneumonia is characterized by an acute inflammatory response in the lung, which is frequently associated with changes in coagulation and fibrinolysis in the bronchoalveolar space. Here, we compared the effects of lipoteichoic acid (LTA), a major cell wall component of Gram-positive

  8. Activation of coagulation and inhibition of fibrinolysis in the lung after inhalation of lipopolysaccharide by healthy volunteers

    NARCIS (Netherlands)

    Maris, Nico A.; de Vos, Alex F.; Bresser, Paul; van der Zee, Jaring S.; Meijers, Joost C.; Lijnen, H. Roger; Levi, Marcel; Jansen, Henk M.; van der Poll, Tom

    2005-01-01

    Pneumonia is frequently associated with changes in coagulation and fibrinolysis in the bronchoalveolar space. To determine the effect of lipopolysaccharide (LPS) on the hemostatic balance in the human lung, six healthy subjects inhaled nebulized LPS or saline in a randomized cross-over study and

  9. Growth hormone replacement normalizes impaired fibrinolysis: new insights into endothelial dysfunction in patients with hypopituitarism and growth hormone deficiency.

    Science.gov (United States)

    Miljic, D; Miljic, P; Doknic, M; Pekic, S; Stojanovic, M; Cvijovic, G; Micic, D; Popovic, V

    2013-12-01

    Cardiovascular morbidity in adult patients with growth hormone deficiency (GHD) and hypopituitarism is increased. Clustering of cardiovascular risk factors leading to endothelial dysfunction and impaired fibrinolysis has also been reported and may account for progression to overt vascular changes in these patients. However, effect of long lasting GH replacement therapy on fibrinolytic capacity in GH deficient patients has not been investigated so far. To investigate fibrinolysis before and after challenge with venous occlusion in GHD patients with hypopituitarism before and during one year of growth hormone replacement. Hospital based, interventional, prospective study. Twenty one patient with GHD and fourteen healthy control subjects matched for age, sex and body mass index (BMI). Anthropometric, metabolic and fibrinolytic parameters were measured at the start and after three, six and twelve months of treatment with human recombinant GH. At baseline GHD patients had significantly impaired fibrinolysis compared to healthy persons. During treatment with GH, significant changes were observed in insulin like growth factor 1(IGF-1) [from baseline 6.9(2.4-13.5) to 22.0(9.0-33.0) nmol/l after one month of treatment; p<0.01] and fibrinolysis. Improvement in fibrinolysis was mostly attributed to improvement of stimulated endothelial tissue plasminogen activator (t-PA) release in response to venous occlusion [from baseline 1.1(0.4-2.6) to 1.9(0.5-8.8) after one year of treatment; p<0.01]. Growth hormone replacement therapy has favorable effects on t-PA release from endothelium and net fibrinolytic capacity in GHD adults, which may contribute to decrease their risk of vascular complications. © 2013.

  10. Effect of Puumala hantavirus infection on Human Umbilical Vein Endothelial Cell hemostatic function: platelet interactions, increased tissue factor expression and fibrinolysis regulator release

    Directory of Open Access Journals (Sweden)

    Marco Goeijenbier

    2015-03-01

    Full Text Available Puumala virus (PUUV infection causes over 5000 cases of hemorrhagic fever in Europe annually and can influence the hemostatic balance extensively. Infection might lead to hemorrhage, while a recent study showed an increased risk of myocardial infarction during or shortly after PUUV infection. The mechanism by which this hantavirus influences the coagulation system remains unknown. Therefore we aimed to elucidate mechanisms explaining alterations seen in primary and secondary hemostasis during PUUV infection. By using low passage PUUV isolates to infect primary human umbilical vein endothelial cells (HUVECs we were able to show alterations in the regulation of primary- and secondary hemostasis and in the release of fibrinolysis regulators. Our main finding was an activation of secondary hemostasis due to increased tissue factor expression leading to increased thrombin generation in a functional assay. Furthermore, we showed that during infection platelets adhered to HUVECs and subsequently specifically to PUUV virus particles. Infection of HUVECs with PUUV did not result in increased von Willebrand factor while they produced more plasminogen activator inhibitor type-1 (PAI-1 compared to controls. The PAI-1 produced in this model formed complexes with vitronectin. This is the first report that reveals a potential mechanism behind the pro-coagulant changes in PUUV patients, which could be the result of increased thrombin generation due to an increased tissue factor expression on endothelial cells during infection. Furthermore, we provide insight into the contribution of endothelial cell responses regarding hemostasis in PUUV pathogenesis.

  11. Effect of Two Lipoprotein (a-Associated Genetic Variants on Plasminogen Levels and Fibrinolysis

    Directory of Open Access Journals (Sweden)

    Hong Wang

    2016-11-01

    Full Text Available Two genetic variants (rs3798220 and rs10455872 in the apolipoprotein (a gene (LPA have been implicated in cardiovascular disease (CVD, presumably through their association with lipoprotein (a [Lp(a] levels. While Lp(a is recognized as a lipoprotein with atherogenic and thrombogenic characteristics, it is unclear whether or not the two Lp(a-associated genetic variants are also associated with markers of thrombosis (i.e., plasminogen levels and fibrinolysis. In the present study, we genotyped the two genetic variants in 2919 subjects of the Old Order Amish (OOA and recruited 146 subjects according to the carrier and noncarrier status for rs3798220 and rs10455872, and also matched for gender and age. We measured plasma Lp(a and plasminogen levels in these subjects, and found that the concentrations of plasma Lp(a were 2.62- and 1.73-fold higher in minor allele carriers of rs3798220 and rs10455872, respectively, compared with noncarriers (P = 2.04 × 10−17 and P = 1.64 × 10−6, respectively. By contrast, there was no difference in plasminogen concentrations between carriers and noncarriers of rs3798220 and rs10455872. Furthermore, we observed no association between carrier status of rs3798220 or rs10455872 with clot lysis time. Finally, plasminogen mRNA expression in liver samples derived from 76 Caucasian subjects was not significantly different between carriers and noncarriers of these two genetic variants. Our results provide further insight into the mechanism of action behind two genetic variants previously implicated in CVD risk and show that these polymorphisms are not major modulating factors for plasma plasminogen levels and fibrinolysis.

  12. Extending the fundamental imaging-depth limit of multi-photon microscopy by imaging with photo-activatable fluorophores.

    Science.gov (United States)

    Chen, Zhixing; Wei, Lu; Zhu, Xinxin; Min, Wei

    2012-08-13

    It is highly desirable to be able to optically probe biological activities deep inside live organisms. By employing a spatially confined excitation via a nonlinear transition, multiphoton fluorescence microscopy has become indispensable for imaging scattering samples. However, as the incident laser power drops exponentially with imaging depth due to scattering loss, the out-of-focus fluorescence eventually overwhelms the in-focal signal. The resulting loss of imaging contrast defines a fundamental imaging-depth limit, which cannot be overcome by increasing excitation intensity. Herein we propose to significantly extend this depth limit by multiphoton activation and imaging (MPAI) of photo-activatable fluorophores. The imaging contrast is drastically improved due to the created disparity of bright-dark quantum states in space. We demonstrate this new principle by both analytical theory and experiments on tissue phantoms labeled with synthetic caged fluorescein dye or genetically encodable photoactivatable GFP.

  13. Fibrinolysis and proliferative endarteritis: two related processes in chronic infections? The model of the blood-borne pathogen Dirofilaria immitis.

    Directory of Open Access Journals (Sweden)

    Javier González-Miguel

    Full Text Available The interaction between blood-borne pathogens and fibrinolysis is one of the most important mechanisms that mediate invasion and the establishment of infectious agents in their hosts. However, overproduction of plasmin (final product of the route has been related in other contexts to proliferation and migration of the arterial wall cells and degradation of the extracellular matrix. We have recently identified fibrinolysis-activating antigens from Dirofilaria immitis, a blood-borne parasite whose key pathological event (proliferative endarteritis is produced by similar mechanisms to those indicated above. The objective of this work is to study how two of this antigens [actin (ACT and fructose-bisphosphate aldolase (FBAL] highly conserved in pathogens, activate fibrinolysis and to establish a relationship between this activation and the development of proliferative endarteritis during cardiopulmonary dirofilariasis. We demonstrate that both proteins bind plasminogen, enhance plasmin generation, stimulate the expression of the fibrinolytic activators tPA and uPA in endothelial cell cultures and are located on the surface of the worm in contact with the host's blood. ELISA, western blot and immunofluorescence techniques were employed for this purpose. Additionally, the implication of lysine residues in this interaction was analyzed by bioinformatics. The involvement of plasmin generated by the ACT/FBAL and plasminogen binding in cell proliferation and migration, and degradation of the extracellular matrix were shown in an "in vitro" model of endothelial and smooth muscle cells in culture. The obtained results indicate that ACT and FBAL from D. immitis activate fibrinolysis, which could be used by the parasite like a survival mechanism to avoid the clot formation. However, long-term overproduction of plasmin can trigger pathological events similar to those described in the emergence of proliferative endarteritis. Due to the high degree of

  14. Platelet microparticle-inspired clot-responsive nanomedicine for targeted fibrinolysis.

    Science.gov (United States)

    Pawlowski, Christa L; Li, Wei; Sun, Michael; Ravichandran, Kavya; Hickman, DaShawn; Kos, Clarissa; Kaur, Gurbani; Sen Gupta, Anirban

    2017-06-01

    Intravascular administration of plasminogen activators is a clinically important thrombolytic strategy to treat occlusive vascular conditions. A major issue with this strategy is the systemic off-target drug action, which affects hemostatic capabilities and causes substantial hemorrhagic risks. This issue can be potentially resolved by designing technologies that allow thrombus-targeted delivery and site-specific action of thrombolytic drugs. To this end, leveraging a liposomal platform, we have developed platelet microparticle (PMP)-inspired nanovesicles (PMINs), that can protect encapsulated thrombolytic drugs in circulation to prevent off-target uptake and action, anchor actively onto thrombus via PMP-relevant molecular mechanisms and allow drug release via thrombus-relevant enzymatic trigger. Specifically, the PMINs can anchor onto thrombus via heteromultivalent ligand-mediated binding to active platelet integrin GPIIb-IIIa and P-selectin, and release the thrombolytic payload due to vesicle destabilization triggered by clot-relevant enzyme phospholipase-A 2 . Here we report on the evaluation of clot-targeting efficacy, lipase-triggered drug release and resultant thrombolytic capability of the PMINs in vitro, and subsequently demonstrate that intravenous delivery of thrombolytic-loaded PMINs can render targeted fibrinolysis without affecting systemic hemostasis, in vivo, in a carotid artery thrombosis model in mice. Our studies establish significant promise of the PMIN technology for safe and site-targeted nanomedicine therapies in the vascular compartment. Copyright © 2017. Published by Elsevier Ltd.

  15. Visualization of Protease Activity In Vivo Using an Activatable Photo-Acoustic Imaging Probe Based on CuS Nanoparticles

    Science.gov (United States)

    Yang, Kai; Zhu, Lei; Nie, Liming; Sun, Xiaolian; Cheng, Liang; Wu, Chenxi; Niu, Gang; Chen, Xiaoyuan; Liu, Zhuang

    2014-01-01

    Herein, we for the first time report a novel activatable photoacoustic (PA) imaging nano-probe for in vivo detection of cancer-related matrix metalloproteinases (MMPs). A black hole quencher 3 (BHQ3) which absorbs red light is conjugated to near-infrared (NIR)-absorbing copper sulfide (CuS) nanoparticles via a MMP-cleavable peptide linker. The obtained CuS-peptide-BHQ3 (CPQ) nano-probe exhibits two distinctive absorption peaks at 630 nm and 930 nm. Inside the tumor microenviorment where MMPs present, the MMP-sensitive peptide would be cleaved, releasing BHQ3 from the CuS nanoparticles, the former of which as a small molecule is then rapidly cleared out from the tumor, whereas the latter of which as large nanoparticles would retain inside the tumor for a much longer period of time. As the result, the PA signal at 680 nm which is contributed by BHQ3 would be quickly diminished while that at 930 nm would be largely retained. The PA signal ratio of 680 nm / 930 nm could thus serve as an in vivo indicator of MMPs activity inside the tumor. Our work presents a novel strategy of in vivo sensing of MMPs based on PA imaging, which should offer remarkably improved detection depth compared with traditional optical imaging techniques. PMID:24465271

  16. Large-scale preparation of active caspase-3 in E. coli by designing its thrombin-activatable precursors

    Directory of Open Access Journals (Sweden)

    Park Sung

    2008-12-01

    Full Text Available Abstract Background Caspase-3, a principal apoptotic effector that cleaves the majority of cellular substrates, is an important medicinal target for the treatment of cancers and neurodegenerative diseases. Large amounts of the protein are required for drug discovery research. However, previous efforts to express the full-length caspase-3 gene in E. coli have been unsuccessful. Results Overproducers of thrombin-activatable full-length caspase-3 precursors were prepared by engineering the auto-activation sites of caspase-3 precursor into a sequence susceptible to thrombin hydrolysis. The engineered precursors were highly expressed as soluble proteins in E. coli and easily purified by affinity chromatography, to levels of 10–15 mg from 1 L of E. coli culture, and readily activated by thrombin digestion. Kinetic evaluation disclosed that thrombin digestion enhanced catalytic activity (kcat/KM of the precursor proteins by two orders of magnitude. Conclusion A novel method for a large-scale preparation of active caspase-3 was developed by a strategic engineering to lack auto-activation during expression with amino acid sequences susceptible to thrombin, facilitating high-level expression in E. coli. The precursor protein was easily purified and activated through specific cleavage at the engineered sites by thrombin, generating active caspase-3 in high yields.

  17. Endovascular recanalization of acute intracranial vertebrobasilar artery occlusion using local fibrinolysis and additional balloon angioplasty

    International Nuclear Information System (INIS)

    Kashiwagi, Junji; Okahara, Mika; Kiyosue, Hiro; Tanoue, Shuichi; Sagara, Yoshiko; Mori, Hiromu; Hori, Yuzo; Abe, Toshi

    2010-01-01

    Vertebrobasilar artery occlusion (VBO) produces high mortality and morbidity due to low recanalization rate utilization in endovascular therapy. The use of percutaneous transluminal angioplasty (PTA) to improve recanalization rate additional to local intra-arterial fibrinolysis (LIF) was investigated in this study. Results obtained following recanalization therapy in acute intracranial VBO are reported. Eighteen consecutive patients with acute VBO underwent LIF with or without PTA, from August 2000 to May 2006. Eight patients were treated using LIF alone, and ten required additional PTA. Rate of recanalization, neurological status before treatment, and clinical outcomes were evaluated. Of 18 patients, 17 achieved recanalization. One procedure-related complication of subarachnoid hemorrhage occurred. Overall survival rate was 94.4% at discharge. Seven patients achieved good outcomes [modified Rankin scale (mRS) 0-2], and the other 11 had poor outcomes (mRS 3-6). Five of six patients who scored 9-14 on the Glasgow Coma Scale (GCS) before treatment displayed good outcomes, whereas ten of 12 patients who scored 3-8 on the GCS showed poor outcomes. GCS prior to treatment showed a statistically significant correlation to outcomes (p < 0.05). Moreover, the National Institutes of Health Stroke Scale (NIHSS) before treatment correlated well with mRS (correlation coefficient 0.487). No statistical difference between the good and poor outcome groups was observed for the duration of symptoms, age, etiology, and occlusion site. Endovascular recanalization can reduce mortality and morbidity of acute VBO. Good GCS and NIHSS scores prior to treatment can predict the efficacy of endovascular recanalization. (orig.)

  18. Estriol-induced fibrinolysis due to the activation of plasminogen to plasmin by nitric oxide synthesis in platelets.

    Science.gov (United States)

    Jana, Pradipta; Maiti, Smarajit; Kahn, Nighat N; Sinha, Asru K

    2015-04-01

    Estriol, an oestrogen, at 0.6 nmol/l was reported to inhibit ADP-induced platelet aggregation through nitric oxide synthesis. As nitric oxide has been reported to cause fibrinolysis due to the activation of plasminogen to plasmin, the role of estriol as a fibrinolytic agent was investigated. Also, the mechanism of estriol-induced nitric oxide synthesis in anucleated platelets was investigated. The estriol-induced lysis of platelet-rich plasma (PRP) clot was determined by photography of the clot lysis and by the assay of fibrin degradation products in the lysate and was obtained by SDS-PAGE. Nitric oxide was determined by methemoglobin method. The platelet membrane protein was isolated from the platelets by using Triton X-100 (0.05% v/v). The binding of estriol to the protein was determined by Scatchard plot by using an ELISA for estriol. Estriol at 0.6 nmol/l was found to lyse the clotted PRP due to fibrinolysis that produced fibrin degradation products in the lysate. The amino acid analysis of the platelet membrane protein, which resembles with nitric oxide synthase (NOS) activity, was activated nearly 10-fold over the control in the presence of estriol and was identified to be a human serum albumin precursor (Mr. 69 kDa) that binds to estriol with Kd1 of 6.0 × 10 mol/l and 39 ± 2 molecules of estriol bound the NOS molecule. The estriol-induced nitric oxide is capable of inducing fibrinolysis of the clotted PRP. The binding of estriol to platelet membrane NOS activated the enzyme in the absence of DNA in the platelet.

  19. Blood markers of coagulation, fibrinolysis, endothelial dysfunction and inflammation in lacunar stroke versus non-lacunar stroke and non-stroke: systematic review and meta-analysis.

    Science.gov (United States)

    Wiseman, Stewart; Marlborough, Fergal; Doubal, Fergus; Webb, David J; Wardlaw, Joanna

    2014-01-01

    The cause of cerebral small vessel disease is not fully understood, yet it is important, accounting for about 25% of all strokes. It also increases the risk of having another stroke and contributes to about 40% of dementias. Various processes have been implicated, including microatheroma, endothelial dysfunction and inflammation. A previous review investigated endothelial dysfunction in lacunar stroke versus mostly non-stroke controls while another looked at markers of inflammation and endothelial damage in ischaemic stroke in general. We have focused on blood markers between clinically evident lacunar stroke and other subtypes of ischaemic stroke, thereby controlling for stroke in general. We systematically assessed the literature for studies comparing blood markers of coagulation, fibrinolysis, endothelial dysfunction and inflammation in lacunar stroke versus non-stroke controls or other ischaemic stroke subtypes. We assessed the quality of included papers and meta-analysed results. We split the analysis on time of blood draw in relation to the stroke. We identified 1,468 full papers of which 42 were eligible for inclusion, including 4,816 ischaemic strokes, of which 2,196 were lacunar and 2,500 non-stroke controls. Most studies subtyped stroke using TOAST. The definition of lacunar stroke varied between studies. Markers of coagulation/fibrinolysis (tissue plasminogen activator (tPA), plasminogen activator inhibitor (PAI), fibrinogen, D-dimer) were higher in lacunar stroke versus non-stroke although fibrinogen was no different to non-stroke in the acute phase. tPA and PAI were no different between lacunar and non-lacunar stroke. Fibrinogen and D-dimer were significantly lower in lacunar stroke compared to other ischaemic strokes, both acutely and chronically. Markers of endothelial dysfunction (homocysteine, von Willebrand Factor (vWF), E-selectin, P-selectin, intercellular adhesion molecule-1 (ICAM), vascular cellular adhesion molecule-1 (VCAM)) were higher or

  20. Massive Pulmonary Embolism: Treatment with Thrombus Fragmentation and Local Fibrinolysis with Recombinant Human-Tissue Plasminogen Activator

    International Nuclear Information System (INIS)

    Stock, Klaus Wilhelm; Jacob, Augustinus Ludwig; Schnabel, Karl Jakob; Bongartz, Georg; Steinbrich, Wolfgang

    1997-01-01

    Purpose: To report the results of thrombus fragmentation in combination with local fibrinolysis using recombinant human-tissue plasminogen activator (rtPA) in patients with massive pulmonary embolism. Methods: Five patients with massive pulmonary embolism were treated with thrombus fragmentation followed by intrapulmonary injection of rtPA. Clot fragmentation was performed with a guidewire, angiographic catheter, and balloon catheter. Three patients had undergone recent surgery; one of them received a reduced dosage of rtPA. Results: All patients survived and showed clinical improvement with a resultant significant (p < 0.05) decrease in the pulmonary blood pressure (mean systolic pulmonary blood pressure before treatment, 49 mmHg; 4 hr after treatment, 28 mmHg). Angiographic follow-up in three patients revealed a decrease in thrombus material and an increase in pulmonary perfusion. Two patients developed retroperitoneal hematomas requiring transfusion. Conclusion: Clot fragmentation and local fibrinolysis with rtPA was an effective therapy for massive pulmonary embolism. Bleeding at the puncture site was a frequent complication

  1. 14-Day thawed plasma retains clot enhancing properties and inhibits tPA-induced fibrinolysis.

    Science.gov (United States)

    Huebner, Benjamin R; Moore, Ernest E; Moore, Hunter B; Shepherd-Singh, Raymond; Sauaia, Angela; Stettler, Gregory R; Nunns, Geoffrey R; Silliman, Christopher C

    2017-11-01

    Plasma-first resuscitation attenuates trauma-induced coagulopathy (TIC); however, the logistics of plasma-first resuscitation require thawed plasma (TP) be readily available due to the obligatory thawing time of fresh frozen plasma (FFP). The current standard is storage of TP for up to 5 days at 4°C, based on factor levels at outdate, for use in patients at risk for TIC, but there remains a 2.2% outdated wastage rate. However, the multitude of plasma proteins in attenuating TIC remains unknown. We hypothesize that TP retains the ability to enhance clotting and reduce tPA-induced fibrinolysis at 14-day storage. FFP was thawed and stored at 4°C at the following intervals: 14, 10, 7, 5, 3, and 1-day prior to the experiment. Healthy volunteers underwent blood draws followed by 50% dilution with TP stored at previously mentioned intervals as well as FFP, normal saline (NS), albumin, and whole blood (WB) control. Samples underwent tPA-modified (75 ng/mL) thrombelastography (TEG) with analysis of R-time, angle, maximum amplitude (MA), and LY30. TEG properties did not change significantly over the thawed storage. 14-day TP retained the ability to inhibit tPA-induced hyperfibrinolysis (median LY30% 9.6%) similar to FFP (5.6%), WB (14.6%), and superior to albumin (59.3%) and NS (58.1%). 14-day TP also retained faster clot formation (median angle, 66.2°) and superior clot strength (MA, 61.5 mm) to albumin (34.8°, 21.6 mm) and NS (41.6°, 32.2 mm). TP plasma stored for 14 days retains clot-enhancing ability and resistance to clot degradation similar to FFP. A clinical trial is needed to validate these in vitro results. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Urinary coagulation-fibrinolysis, kallirein-kinin systems and kininase in cases of preclampsia.

    Science.gov (United States)

    Mutoh, S; Kobayashi, M; Hirata, J; Itoh, N; Maki, M; Komatsu, Y; Yoshida, A; Sasa, H; Kuroda, K; Kikuchi, Y

    1992-01-01

    Urinary kallikrein and kallikrein activity significantly decreased in cases of preeclampsia (u-kall./CRE.index 42.39 +/- 9.66 ng/mg, u-kall. act./CRE.index 0.26 +/- 0.06 ng/min/mg), and urinary kininase II and kininase activity significantly increased (u-kininase/CRE.index 10.91 +/- 1.26 x 10(-3) IU/min/mg, u-kininase act./CRE.index 506.37 +/- 178.45 pg/min/mg) when compared with those of normal gravidas from 28 weeks to 42 weeks of gestation (u-kall./CRE.index 189.31 +/- 14.17 ng/mg, u-kall. act./CRE index 1.08 +/- 0.10 ng/min/mg, u-kininase/CRE.index 6.24 +/- 0.31 x 10(-3) IU/min/mg, u-kininase act./CRE.index 15.64 +/- 0.10 pg/min/mg). Urinary FPA, B beta 5-42, alpha 2-PI, and alpha 2PI-plasmin-complex (PIC) significantly increased in preeclampsia (u-FPA/CRE.index 23.59 +/- 8.47 ng/mg, u-B beta/CRE.index 105.26 +/- 29.30 ng/mg, u-alpha 2PI/CRE.index 121.53 +/- 43.57 ng/mg, u-PIC/CRE index 278.39 +/- 60.50 ng/mg) when compared with those of normal control group (u-FPA/CRE.index 0.92 +/- 0.04 ng/mg, u-B beta/CRE.index 12.15 +/- 0.44 ng/mg, u-alpha 2PI/CRE.index 4.18 +/- 0.33 ng/mg, u-PIC/CRE.index 5.98 +/- 1.15 ng/mg). Urinary urokinase markedly increased and urinary D-dimer was detected in severe cases of preeclampsia (u-UK/CRE.index 58.20 +/- 43.69 ng/mg, u-D-dimer 54.76 +/- 9.89 ng/ml) when compared with those of normal control group. These findings suggest that deficiency in urinary kinin excretion may induce hypertension in addition to the changes of urinary coagulation-fibrinolysis system that represents the occurrence of either the endothelial cell injury in the glomerulus or the renal tulbular damage in mild cases of preeclampsia, eventually resulting in the intra-renal vascular coagulation.

  3. A lysosome-locating and acidic pH-activatable fluorescent probe for visualizing endogenous H2O2 in lysosomes.

    Science.gov (United States)

    Liu, Jun; Zhou, Shunqing; Ren, Jing; Wu, Chuanliu; Zhao, Yibing

    2017-11-20

    There is increasing evidence indicating that lysosomal H 2 O 2 is closely related to autophagy and apoptotic pathways under both physiological and pathological conditions. Therefore, fluorescent probes that can be exploited to visualize H 2 O 2 in lysosomes are potential tools for exploring diverse roles of H 2 O 2 in cells. However, functional exploration of lysosomal H 2 O 2 is limited by the lack of fluorescent probes capable of compatibly sensing H 2 O 2 under weak acidic conditions (pH = 4.5) of lysosomes. Lower spatial resolution of the fluorescent visualization of lysosomal H 2 O 2 might be caused by the interference of signals from cytosolic and mitochondrial H 2 O 2 , as well as the non-specific distribution of the probes in cells. In this work, we developed a lysosome-locating and acidic-pH-activatable fluorescent probe for the detection and visualization of H 2 O 2 in lysosomes, which consists of a H 2 O 2 -responsive boronate unit, a lysosome-locating morpholine group, and a pH-activatable benzorhodol fluorophore. The response of the fluorescent probe to H 2 O 2 is significantly more pronounced under acidic pH conditions than that under neutral pH conditions. Notably, the present probe enables the fluorescence sensing of endogenous lysosomal H 2 O 2 in living cells without external stimulations, with signal interference from the cytoplasm and other intracellular organelles being negligible.

  4. Quantitative modeling of the dynamics and intracellular trafficking of far-red light-activatable prodrugs: implications in stimuli-responsive drug delivery system.

    Science.gov (United States)

    Li, Mengjie; Thapa, Pritam; Rajaputra, Pallavi; Bio, Moses; Peer, Cody J; Figg, William D; You, Youngjae; Woo, Sukyung

    2017-12-01

    The combination of photodynamic therapy (PDT) with anti-tumor agents is a complimentary strategy to treat local cancers. We developed a unique photosensitizer (PS)-conjugated paclitaxel (PTX) prodrug in which a PS is excited by near-infrared wavelength light to site-specifically release PTX while generating singlet oxygen (SO) to effectively kill cancer cells with both PTX and SO. The aim of the present study was to identify the determinants influencing the combined efficacy of this light-activatable prodrug, especially the bystander killing effects from released PTX. Using PS-conjugated PTX as a model system, we developed a quantitative mathematical model describing the intracellular trafficking. Dynamics of the prodrug and the model predictions were verified with experimental data using human cancer cells in vitro. The sensitivity analysis suggested that parameters related to extracellular concentration of released PTX, prodrug uptake, target engagement, and target abundance are critical in determining the combined killing efficacy of the prodrug. We found that released PTX cytotoxicity was most sensitive to the retention time of the drug in extracellular space. Modulating drug internalization and conjugating the agents targeted to abundant receptors may provide a new strategy for maximizing the killing capacity of the far-red light-activatable prodrug system. These results provide guidance for the design of the PDT combination study in vivo and have implications for other stimuli-responsive drug delivery systems.

  5. Effects of gastric bypass followed by a randomized study of physical training on markers of coagulation activation, fibrin clot properties, and fibrinolysis

    DEFF Research Database (Denmark)

    Stolberg, Charlotte Røn; Mundbjerg, Lene Hymøller; Funch-Jensen, Peter

    2018-01-01

    disease risk markers within coagulation activation, fibrin clot properties, and fibrinolysis. Setting: Bariatric center, Hospital of Southwest Jutland, Denmark. Methods: Sixty obese patients underwent RYGB and 6 months after RYGB were randomized to 26 weeks of physical training or a control group...

  6. Association between sympathoadrenal activation, fibrinolysis, and endothelial damage in septic patients

    DEFF Research Database (Denmark)

    Johansson, Pär I; Haase, Nicolai; Perner, Anders

    2014-01-01

    for Severe Sepsis/Septic Shock trial who were expected not to receive catecholamines at screening preintervention (baseline) and had baseline blood sampled. Clinical, outcome data, and measurements of plasma concentration (p-) biomarkers reflecting sympathoadrenal activation, endothelial activation......-type plasminogen activator, and plasminogen activator inhibitor 1 (PAI-1) and negatively with PAI-1/tissue-type plasminogen activator ratio (all PPAI-1 (all P

  7. [Evaluation of selected parameters of blood coagulation and fibrinolysis system in patients undergoing total hip replacement surgery with normovolemic hemodilution procedure and standard enoxaparine prophylaxis].

    Science.gov (United States)

    Piecuch, Wiesław; Sokołowska, Bozena; Dmoszyńska, Anna; Furmanik, Franciszek

    2003-01-01

    The aim of the study was to evaluate selected blood coagulation and fibrinolysis parameters in patients undergoing total hip replacement surgery with normovolemic hemodilution and standard enoksaparine profilaxis. The study included 66 patients undergoing hip replacement surgery. The group consisted of 51 women and 15 men, within the age range of 47-78, the mean age was 64. In 32 (subgroup II) patients the surgery was performed with the use of normovolemic hemodilution, in 34 (subgroup I) the hemodilution procedure was not applied. The enoksaparine as prophylaxis started 12 hours prior to surgery and continued during hospitalisation. The examination of the coagulation system was performed: on the day of the operation in the morning, on the day of the operation in the evening and on the first day after operation. We determined the concentrations of TAT and PAP complexes, prothrombin fragments 1 + 2 (F1 + 2) and d-dimers (DD). 1) during total hip replacement surgery and particularly in the period of the first 12 hours after the procedure marked activation of coagulation and fibrinolysis occurRed; 2) the application of the hemodilution procedure does not influence significantly the degree of coagulation and fibrinolysis disorders in the perioperative period, but could reduced incidence of thromboembolic complications in the postoperative period.

  8. The effects of residual platelets in plasma on plasminogen activator inhibitor-1 and plasminogen activator inhibitor-1-related assays.

    Directory of Open Access Journals (Sweden)

    Marlien Pieters

    Full Text Available Due to controversial evidence in the literature pertaining to the activity of plasminogen activator inhibitor-1 in platelets, we examined the effects of residual platelets present in plasma (a potential pre-analytical variable on various plasminogen activator inhibitor-1 and plasminogen activator inhibitor-1-related assays. Blood samples were collected from 151 individuals and centrifuged at 352 and 1500 g to obtain plasma with varying numbers of platelet. In a follow-up study, blood samples were collected from an additional 23 individuals, from whom platelet-poor (2000 g, platelet-containing (352 g and platelet-rich plasma (200 g were prepared and analysed as fresh-frozen and after five defrost-refreeze cycles (to determine the contribution of in vitro platelet degradation. Plasminogen activator inhibitor-1 activity, plasminogen activator inhibitor-1 antigen, tissue plasminogen activator/plasminogen activator inhibitor-1 complex, plasma clot lysis time, β-thromboglobulin and plasma platelet count were analysed. Platelet α-granule release (plasma β-thromboglobulin showed a significant association with plasminogen activator inhibitor-1 antigen levels but weak associations with plasminogen activator inhibitor-1 activity and a functional marker of fibrinolysis, clot lysis time. Upon dividing the study population into quartiles based on β-thromboglobulin levels, plasminogen activator inhibitor-1 antigen increased significantly across the quartiles while plasminogen activator inhibitor-1 activity and clot lysis time tended to increase in the 4th quartile only. In the follow-up study, plasma plasminogen activator inhibitor-1 antigen was also significantly influenced by platelet count in a concentration-dependent manner. Plasma plasminogen activator inhibitor-1 antigen levels increased further after complete platelet degradation. Residual platelets in plasma significantly influence plasma plasminogen activator inhibitor-1 antigen levels mainly

  9. Increased Coagulation and Decreased Fibrinolysis as Measured with Overall Hemostatic Potential Are Dependent on BMI and Not Associated with PCOS.

    Science.gov (United States)

    Rakusa, Matej; Jensterle, Mojca; Božič-Mijovski, Mojca; Janez, Andrej

    2017-05-01

    Overall hemostatic potential (OHP) captures all factors that affect coagulation and fibrinolysis cascade. It has not yet been assessed in polycystic ovary syndrome (PCOS). The aim of the study was to identify the relationship of OHP with a syndrome per se and body mass index (BMI). In 90 women with PCOS aged 30.9 ± 8.1 years (50 obese, 13 overweight, and 27 lean) and 21 healthy age-matched controls (11 obese and 10 lean), OHP with overall coagulation potential (OCP) and overall fibrinolytic potential (OFP) was determined spectrophotometrically. OFP was calculated. OHP increased with BMI in PCOS (9.6 ± 2.3 in lean, 12.5 ± 5.1 in overweight, and 15.5 ± 3.8 Abs-sum in obese) and in controls (9.1 ± 1.0 in lean and 17.3 ± 4.6 Abs-sum in obese). There was significant difference between lean and obese PCOS (P PCOS (P PCOS (P PCOS did not differ significantly, while OHP for healthy obese was increased in comparison to overweight and lean PCOS (P PCOS was not associated with increased OHP compared with BMI and age-matched controls. However, increase in OHP was positively associated with BMI in PCOS and healthy women.

  10. In-vitro effects of tri-iodinated X-ray contrast media on blood coagulation, fibrinolysis and complement system

    International Nuclear Information System (INIS)

    Blanke, D.

    1982-01-01

    In-vitro experiments with Jodipamid, Jothalamat and Diatrizoat served the purpose of determining influences of contrast media on blood coagulation, fibrinolysis and the complement system. For all three contrast media investigated the effect noted was dose-dependent and was only brought about by concentrations higher than physiological ones. Liver-pathway Jodipamid was seen to have a much stronger effect than the two renal-pathway contrast media Jothalamat and Diatrizoat, which is probably due to the different protein binding capacities. In detail, the results with Jodipamid were as follows: a sharp fall in thrombinogen, a distinct decrease in fibrinogen both in the immunological and functional test, but only delayed decrease in complement factor C 4. Fibrinolytic fission products were found after applying the dose of 30 mM, as compared to 400 mM for the renal-pathway contrast media. Furthermore the functional tests (F I and F II) with Jothalamat and Diatrizoat showed only slight effects, the immunological ones (F I and C 4) none at all. The influence of the contrast media on factors I and II is interpreted by the author as an inhibition of fibrin polymerization. What seems to be the verification of fibrinolytic fission products is explained by a non-specific agglutination reaction, the decrease in C 4 by contrast-medium-induced protein denaturation. (orig./MG) [de

  11. Altered protein expression in gestational diabetes mellitus placentas provides insight into insulin resistance and coagulation/fibrinolysis pathways.

    Directory of Open Access Journals (Sweden)

    Bin Liu

    Full Text Available OBJECTIVE: To investigate the placental proteome differences between pregnant women complicated with gestational diabetes mellitus (GDM and those with normal glucose tolerance (NGT. METHODS: We used two-dimensional electrophoresis (2DE to separate and compare placental protein levels from GDM and NGT groups. Differentially expressed proteins between the two groups were identified by MALDI-TOF/TOF mass spectrometry and further confirmed by Western blotting. The mRNA levels of related proteins were measured by realtime RT-PCR. Immunohistochemistry (IHC was performed to examine the cellular location of the proteins expressed in placenta villi. RESULTS: Twenty-one protein spots were differentially expressed between GDM and NGT placenta villi in the tested samples, fifteen of which were successfully identified by mass spectrometry. The molecular functions of these differentially expressed proteins include blood coagulation, signal transduction, anti-apoptosis, ATP binding, phospholipid binding, calcium ion binding, platelet activation, and tryptophan-tRNA ligase activity. Both protein and mRNA levels of Annexin A2, Annexin A5 and 14-3-3 protein ζ/δ were up-regulated, while the expression of the Ras-related protein Rap1A was down-regulated in the GDM placenta group. CONCLUSION: Placenta villi derived from GDM pregnant women exhibit significant proteome differences compared to those of NGT mothers. The identified differentially expressed proteins are mainly associated with the development of insulin resistance, transplacental transportation of glucose, hyperglucose-mediated coagulation and fibrinolysis disorders in the GDM placenta villi.

  12. Leukocyte- and endothelial-derived microparticles: a circulating source for fibrinolysis

    Science.gov (United States)

    Lacroix, Romaric; Plawinski, Laurent; Robert, Stéphane; Doeuvre, Loïc; Sabatier, Florence; Martinez de Lizarrondo, Sara; Mezzapesa, Anna; Anfosso, Francine; Leroyer, Aurelie S.; Poullin, Pascale; Jourde, Noémie; Njock, Makon-Sébastien; Boulanger, Chantal M.; Anglés-Cano, Eduardo; Dignat-George, Françoise

    2012-01-01

    Background We recently assigned a new fibrinolytic function to cell-derived microparticles in vitro. In this study we explored the relevance of this novel property of microparticles to the in vivo situation. Design and Methods Circulating microparticles were isolated from the plasma of patients with thrombotic thrombocytopenic purpura or cardiovascular disease and from healthy subjects. Microparticles were also obtained from purified human blood cell subpopulations. The plasminogen activators on microparticles were identified by flow cytometry and enzyme-linked immunosorbent assays; their capacity to generate plasmin was quantified with a chromogenic assay and their fibrinolytic activity was determined by zymography. Results Circulating microparticles isolated from patients generate a range of plasmin activity at their surface. This property was related to a variable content of urokinase-type plasminogen activator and/or tissue plasminogen activator. Using distinct microparticle subpopulations, we demonstrated that plasmin is generated on endothelial and leukocyte microparticles, but not on microparticles of platelet or erythrocyte origin. Leukocyte-derived microparticles bear urokinase-type plasminogen activator and its receptor whereas endothelial microparticles carry tissue plasminogen activator and tissue plasminogen activator/inhibitor complexes. Conclusions Endothelial and leukocyte microparticles, bearing respectively tissue plasminogen activator or urokinase-type plasminogen activator, support a part of the fibrinolytic activity in the circulation which is modulated in pathological settings. Awareness of this blood-borne fibrinolytic activity conveyed by microparticles provides a more comprehensive view of the role of microparticles in the hemostatic equilibrium. PMID:22733025

  13. Activation of TAFI on the surface of Streptococcus pyogenes evokes inflammatory reactions by modulating the kallikrein/kinin system

    NARCIS (Netherlands)

    Bengtson, Sara H.; Sandén, Caroline; Mörgelin, Matthias; Marx, Pauline F.; Olin, Anders I.; Leeb-Lundberg, L. M. Fredrik; Meijers, Joost C. M.; Herwald, Heiko

    2008-01-01

    Bacteria-controlled regulation of host responses to infection is an important virulence mechanism that has been demonstrated to contribute to disease progression. Here we report that the human pathogen Streptococcus pyogenes employs the procarboxypeptidase TAFI (thrombin-activatable fibrinolysis

  14. Addition of Arsenic Trioxide into Induction Regimens Could Not Accelerate Recovery of Abnormality of Coagulation and Fibrinolysis in Patients with Acute Promyelocytic Leukemia.

    Directory of Open Access Journals (Sweden)

    Ye Zhang

    Full Text Available All-trans retinoic acid combined to anthracycline-based chemotherapy is the standard regimen of acute promyelocytic leukemia. The advent of arsenic trioxide has contributed to improve the anti-leukemic efficacy in acute promyelocytic leukemia. The objectives of the current study were to evaluate if dual induction by all-trans retinoic acid and arsenic trioxide could accelerate the recovery of abnormality of coagulation and fibrinolysis in patients with acute promyelocytic leukemia.Retrospective analysis was performed in 103 newly-diagnosed patients with acute promyelocytic leukemia. Hemostatic variables and the consumption of component blood were comparably analyzed among patients treated by different induction regimen with or without arsenic trioxide.Compared to patients with other subtypes of de novo acute myeloid leukemia, patients with acute promyelocytic leukemia had lower platelet counts and fibrinogen levels, significantly prolonged prothrombin time and elevated D-dimers (P<0.001. Acute promyelocytic leukemia patients with high or intermediate risk prognostic stratification presented lower initial fibrinogen level than that of low-risk group (P<0.05. After induction treatment, abnormal coagulation and fibrinolysis of patients with acute promyelocytic leukemia was significantly improved before day 10. The recovery of abnormal hemostatic variables (platelet, prothrombin time, fibrinogen and D-dimer was not significantly accelerated after adding arsenic trioxide in induction regimens; and the consumption of transfused component blood (platelet and plasma did not dramatically change either. Acute promyelocytic leukemia patients with high or intermediate risk prognostic stratification had higher platelet transfusion demands than that of low-risk group (P<0.05.Unexpectedly, adding arsenic trioxide could not accelerate the recovery of abnormality of coagulation and fibrinolysis in acute promyelocytic leukemia patients who received all

  15. Effect of tranexamic acid on coagulation and fibrinolysis in women with postpartum haemorrhage (WOMAN-ETAC): protocol and statistical analysis plan for a randomized controlled trial.

    Science.gov (United States)

    Shakur, Haleema; Fawole, Bukola; Kuti, Modupe; Olayemi, Oladapo; Bello, Adenike; Ogunbode, Olayinka; Kotila, Taiwo; Aimakhu, Chris O; Huque, Sumaya; Gregg, Meghann; Roberts, Ian

    2016-12-16

    Background : Postpartum haemorrhage (PPH) is a leading cause of maternal death. Tranexamic acid has the potential to reduce bleeding and a large randomized controlled trial of its effect on maternal health outcomes in women with PPH (The WOMAN trial) is ongoing. We will examine the effect of tranexamic acid on fibrinolysis and coagulation in a subset of WOMAN trial participants. Methods . Adult women with clinically diagnosed primary PPH after vaginal or caesarean delivery are eligible for inclusion in the WOMAN trial. In a sub-group of trial participants, blood samples will be collected at baseline and 30 minutes after the first dose of tranexamic acid or matching placebo.  Our primary objective is to evaluate the effect of tranexamic acid on fibrinolysis. Fibrinolysis will be assessed by measuring D-dimers and by rotational thromboelastometry (ROTEM). Secondary outcomes are international normalized ratio (INR), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, haemoglobin and platelets. We aim to include about 180 women from the University College Hospital, Ibadan in Nigeria. Discussion:  This sub-study of WOMAN trial participants should provide information on the mechanism of action of tranexamic acid in women with postpartum haemorrhage. We present the trial protocol and statistical analysis plan. The trial protocol was registered prior to the start of patient recruitment. The statistical analysis plan was completed before un-blinding. Trial registration: The trial was registered: ClinicalTrials.gov, Identifier NCT00872469 https://clinicaltrials.gov/ct2/show/NCT00872469; ISRCTN registry, Identifier ISRCTN76912190 http://www.isrctn.com/ISRCTN76912190 (Registration date: 22/03/2012).

  16. Effects on coagulation and fibrinolysis induced by influenza in mice with a reduced capacity to generate activated protein C and a deficiency in plasminogen activator inhibitor type 1

    NARCIS (Netherlands)

    Keller, Tymen T.; van der Sluijs, Koen F.; de Kruif, Martijn D.; Gerdes, Victor E. A.; Meijers, Joost C. M.; Florquin, Sandrine; van der Poll, Tom; van Gorp, Eric C. M.; Brandjes, Dees P. M.; Büller, Harry R.; Levi, Marcel

    2006-01-01

    Influenza infections increase the risk of diseases associated with a prothrombotic state, such as venous thrombosis and atherothrombotic diseases. However, it is unclear whether influenza leads to a prothrombotic state in vivo. To determine whether influenza activates coagulation, we measured

  17. Inhibition of endothelial cell expression of plasminogen activator inhibitor type-1 by gemfibrozil.

    Science.gov (United States)

    Fujii, S; Sawa, H; Sobel, B E

    1993-10-18

    Increased concentrations of plasminogen activator inhibitor type-1 (PAI-1) in plasma are associated with impaired fibrinolysis and venous and arterial thrombo-embolic disease. In pilot studies designed to identify pharmacologic approaches capable of diminishing such increases, we found that gemfibrozil attenuated the stimulation of synthesis of PAI-1 in a human, immortal, hepatoma cell line (Hep G2) induced by platelets. The present study was performed to determine whether it exerts analogous effects in non-immortal endothelial cells and whether it may therefore facilitate fibrinolysis locally in vivo. Human umbilical vein endothelial cells were incubated with pharmacologic concentrations of gemfibrozil. Gemfibrozil, 100 microM, suppressed basal PAI-1 production by 15% and attenuated the augmentation of synthesis of PAI-1 induced by lysates from platelets (4 x 10(7)/ml) by 36% over 24 h without inhibiting overall protein synthesis. In addition, the increases in PAI-1 mRNA otherwise induced by platelet lysates over 6 h were suppressed by 49% (Northern blots) without any demonstrable change in the intracellular half-life of PAI-1 mRNA. Pulse-chase experiments demonstrated diminution of PAI-1 protein synthesis in parallel with the changes observed in PAI-1 mRNA. To determine whether these effects of gemfibrozil on endothelial cells in vitro were paralleled by consistent changes in the concentrations of PAI-1 in plasma in vivo, we studied rabbits with induced carotid artery thrombosis and thrombolysis.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Effect of individual dietary fatty acids on postprandial activation of blood coagulation factor VII and fibrinolysis in healthy young men

    DEFF Research Database (Denmark)

    Tholstrup, T.; Miller, G.J.; Bysted, Anette

    2003-01-01

    Background: Hypertriglyceridemia may represent a procoagulant state involving disturbances to the hemostatic system. Plasminogen activator inhibitor type 1 (PAI-1) is increased in the presence of hypertriglyceridemia. Free fatty acids (FFAs) in plasma may promote factor VII (FVII) activation...

  19. Blocking hepatic metastases of colon cancer cells using an shRNA against Rac1 delivered by activatable cell-penetrating peptide.

    Science.gov (United States)

    Bao, Ying; Guo, Huihui; Lu, Yongliang; Feng, Wenming; Sun, Xinrong; Tang, Chengwu; Wang, Xiang; Shen, Mo

    2016-11-22

    Hepatic metastasis is one of the critical progressions of colon cancer. Blocking this process is key to prolonging survival time in cancer patients. Studies on activatable cell-penetrating peptides (dtACPPs) have demonstrated their potential as gene carriers. It showed high tumor cell-targeting specificity and transfection efficiency and low cytotoxicity in the in vitro settings of drug delivery. However, using this system to silence target genes to inhibit metastasis in colorectal cancer cells has not been widely reported and requires further investigation. In this study, we observed that expression of Rac1, a key molecule for cytoskeletal reorganization, was higher in hepatic metastatic tumor tissue compared with prime colon cancer tissue and that patients with high Rac1-expressing colon cancer showed shorter survival time. Base on these findings, we created dtACPP-PEG-DGL (dtACPPD)/shRac1 nanoparticles and demonstrated that they downregulated Rac1 expression in colon cancer cells. Moreover, we observed inhibitory effects on migration, invasion and adhesion in HCT116 colorectal cancer cells in vitro, and our results showed that Rac1 regulated colon cancer cell matrix adhesion through the regulation of cytofilament dynamics. Moreover, mechanically, repression of Rac1 inhibiting cells migration and invasion by enhancing cell to cell adhesion and reducing cell to extracellular matrix adhesion. Furthermore, when atCDPPD/shRac1 nanoparticles were administered intravenously to a HCT116 xenograft model, significant tumor metastasis to the liver was inhibited. Our results suggest that atCDPP/shRac1 nanoparticles may enable the blockade of hepatic metastasis in colon cancer.

  20. Single-cell resolution imaging of retinal ganglion cell apoptosis in vivo using a cell-penetrating caspase-activatable peptide probe.

    Directory of Open Access Journals (Sweden)

    Xudong Qiu

    Full Text Available Peptide probes for imaging retinal ganglion cell (RGC apoptosis consist of a cell-penetrating peptide targeting moiety and a fluorophore-quencher pair flanking an effector caspase consensus sequence. Using ex vivo fluorescence imaging, we previously validated the capacity of these probes to identify apoptotic RGCs in cell culture and in an in vivo rat model of N-methyl- D-aspartate (NMDA-induced neurotoxicity. Herein, using TcapQ488, a new probe designed and synthesized for compatibility with clinically-relevant imaging instruments, and real time imaging of a live rat RGC degeneration model, we fully characterized time- and dose-dependent probe activation, signal-to-noise ratios, and probe safety profiles in vivo. Adult rats received intravitreal injections of four NMDA concentrations followed by varying TcapQ488 doses. Fluorescence fundus imaging was performed sequentially in vivo using a confocal scanning laser ophthalmoscope and individual RGCs displaying activated probe were counted and analyzed. Rats also underwent electroretinography following intravitreal injection of probe. In vivo fluorescence fundus imaging revealed distinct single-cell probe activation as an indicator of RGC apoptosis induced by intravitreal NMDA injection that corresponded to the identical cells observed in retinal flat mounts of the same eye. Peak activation of probe in vivo was detected 12 hours post probe injection. Detectable fluorescent RGCs increased with increasing NMDA concentration; sensitivity of detection generally increased with increasing TcapQ488 dose until saturating at 0.387 nmol. Electroretinography following intravitreal injections of TcapQ488 showed no significant difference compared with control injections. We optimized the signal-to-noise ratio of a caspase-activatable cell penetrating peptide probe for quantitative non-invasive detection of RGC apoptosis in vivo. Full characterization of probe performance in this setting creates an important in

  1. [Syk inhibitors].

    Science.gov (United States)

    Kimura, Yukihiro; Chihara, Kazuyasu; Takeuchi, Kenji; Sada, Kiyonao

    2013-07-01

    Non-receptor type of protein-tyrosine kinase Syk (spleen tyrosine kinase) was isolated in the University of Fukui in 1991. Syk is known to be essential for the various physiological functions, especially in hematopoietic lineage cells. Moreover, ectopic expression of Syk by epigenetic changes is reported to cause retinoblastoma. Recently, novel Syk inhibitors were developed and its usefulness has been evaluated in the treatment of allergic rhinitis, rheumatoid arthritis, and idiopathic thrombocytopenic purpura. In this review, we will summarize the history, structure, and function of Syk, and then describe the novel Syk inhibitors and their current status. Furthermore, we will introduce our findings of the adaptor protein 3BP2 (c-Abl SH3 domain-binding protein-2), as a novel target of Syk.

  2. Syk inhibitors.

    Science.gov (United States)

    Chihara, Kazuyasu; Kimura, Yukihiro; Honjo, Chisato; Takeuchi, Kenji; Sada, Kiyonao

    2013-01-01

    Non-receptor type of protein-tyrosine kinase Syk (spleen tyrosine kinase) was isolated in University of Fukui in 1991. Syk is most highly expressed by haemopoietic cells and known to play crucial roles in the signal transduction through various immunoreceptors of the adaptive immune response. However, recent reports demonstrate that Syk also mediates other biological functions, such as innate immune response, osteoclast maturation, platelet activation and cellular adhesion. Moreover, ectopic expression of Syk by epigenetic changes is reported to cause retinoblastoma. Because of its critical roles on the cellular functions, the development of Syk inhibitors for clinical use has been desired. Although many candidate compounds were produced, none of them had progressed to clinical trials. However, novel Syk inhibitors were finally developed and its usefulness has been evaluated in the treatment of allergic rhinitis, rheumatoid arthritis and idiopathic thrombocytopenic purpura. In this review, we will summarize the history, structure and function of Syk, and then the novel Syk inhibitors and their current status. In addition, we will introduce our research focused on the functions of Syk on Dectin-1-mediated mast cell activation.

  3. Probing intra-cellular drug release event using activatable (OFF/ON) CdS:Mn/ZnS quantum dots (Qdots): spectroscopic studies to investigate interaction of Qdots with quencher

    Science.gov (United States)

    Tharkur, Jeremy; Teblum, Andrew; Basumallick, Srijita; Shah, Rikhav; Cantarero, Karishma; Maity, Niharika; Rifai, Sara; Doshi, Mona; Gesquiere, Andre J.; Santra, Swadeshmukul

    2013-02-01

    In recent years, activatable Quantum Dots (AQdots) are gaining popularity in a number of chemical and biological sensing applications. A basic design of AQdot probes involves a suitable quencher which is capable of altering optical properties of the Qdots. In our previous studies we have shown that CdS:Mn/ZnS fluorescence can be effectively quenched using small molecule quenchers (such as dopamine, chemotherapeutic drug) as well as iron oxide nanoparticle via electron/energy transfer process. We have also shown that the quenched Qdot fluorescence can be restored when the Qdots are separated from the quencher. Using Qdot based activatable probes, we detected intracellular drug release event. Qdot fluorescence was restored upon interaction with the intracellular glutathione (GSH). In this paper, we report a GSH induced quenching of water-soluble N-Acetyl Cysteine (NAC) surface-conjugated Cds:Mn/ZnS Qdots. Quenching of NAC-Qdots was due to aggregation of Qdots in solution. This aggregation induced fluorescence quenching phenomenon resembles with the self-quenching phenomenon of traditional organic fluorescence dyes at high concentrations. UV-VIS and fluorescence emission spectroscopy data support the interaction and binding of GSH with the NAC-Qdots. Increase in particle size due to GSH induced aggregation of NAC-Qdots was confirmed by the Dynamic Light Scattering (DLS) data.

  4. The Comparison of the Outcomes between Primary PCI, Fibrinolysis, and No Reperfusion in Patients ≥ 75 Years Old with ST-Segment Elevation Myocardial Infarction: Results from the Chinese Acute Myocardial Infarction (CAMI) Registry.

    Science.gov (United States)

    Peiyuan, He; Jingang, Yang; Haiyan, Xu; Xiaojin, Gao; Ying, Xian; Yuan, Wu; Wei, Li; Yang, Wang; Xinran, Tang; Ruohua, Yan; Chen, Jin; Lei, Song; Xuan, Zhang; Rui, Fu; Yunqing, Ye; Qiuting, Dong; Hui, Sun; Xinxin, Yan; Runlin, Gao; Yuejin, Yang

    2016-01-01

    Only a few randomized trials have analyzed the clinical outcomes of elderly ST-segment elevation myocardial infarction (STEMI) patients (≥ 75 years old). Therefore, the best reperfusion strategy has not been well established. An observational study focused on clinical outcomes was performed in this population. Based on the national registry on STEMI patients, the in-hospital outcomes of elderly patients with different reperfusion strategies were compared. The primary endpoint was defined as death. Secondary endpoints included recurrent myocardial infarction, ischemia driven revascularization, myocardial infarction related complications, and major bleeding. Multivariable regression analysis was performed to adjust for the baseline disparities between the groups. Patients who had primary percutaneous coronary intervention (PCI) or fibrinolysis were relatively younger. They came to hospital earlier, and had lower risk of death compared with patients who had no reperfusion. The guideline recommended medications were more frequently used in patients with primary PCI during the hospitalization and at discharge. The rates of death were 7.7%, 15.0%, and 19.9% respectively, with primary PCI, fibrinolysis, and no reperfusion (P PCI also had lower rates of heart failure, mechanical complications, and cardiac arrest compared with fibrinolysis and no reperfusion (P PCI, fibrinolysis, and no reperfusion group (P > 0.05). In the multivariable regression analysis, primary PCI outweighs no reperfusion in predicting the in-hospital death in patients ≥ 75 years old. However, fibrinolysis does not. Early reperfusion, especially primary PCI was safe and effective with absolute reduction of mortality compared with no reperfusion. However, certain randomized trials were encouraged to support the conclusion.

  5. Fibrinolysis and extracorporeal circulation

    NARCIS (Netherlands)

    Kluft, C.

    1992-01-01

    Chemicals/CAS: blood clotting factor 12, 9001-30-3; high molecular weight kininogen, 97792-85-3; plasminogen activator, 9039-53-6; prekallikrein, 9055-02-1; tissue plasminogen activator, 105913-11-9; urokinase, 139639-24-0; Factor XII, 9001-30-3; Kininogens; Prekallikrein, 9055-02-1

  6. 4G/5G Polymorphism of the plasminogen activator inhibitor-1 gene is associated with multiple organ dysfunction in critically ill patients.

    Science.gov (United States)

    Huq, Muhammad Aminul; Takeyama, Naoshi; Harada, Makoto; Miki, Yasuo; Takeuchi, Akinori; Inoue, Sousuke; Nakagawa, Takashi; Kanou, Hideki; Hirakawa, Akihiko; Noguchi, Hiroshi

    2012-01-01

    Impaired fibrinolysis is associated with a higher incidence of both multiple organ dysfunction and mortality in the intensive care unit (ICU). Plasminogen activator inhibitor (PAI)-1 is the chief inhibitor of fibrinolysis. We investigated the influence of the 4G/5G polymorphism (rs1799768) of the PAI-1 gene on the plasma PAI-1 level and the outcome of critically ill patients. In 41 consecutive patients admitted to the ICU, PAI-1 gene polymorphism was assessed, plasma PAI-1 and arterial lactate concentrations were measured and clinical severity scores were recorded. Homozygotes for the 4G allele had higher plasma levels of PAI-1 antigen. The mean ± SD PAI-1 antigen level was 193.31 ± 167.93 ng/ml for the 4G/4G genotype, 100.67 ± 114.16 ng/ml for the 4G/5G genotype and 0.43 ± 0.53 ng/ml for the 5G/5G genotype. There was a significant correlation between plasma PAI-1 and arterial lactate concentrations, as well as between PAI-1 and severity scores. The mortality rate was 63, 33 and 0% for patients with the 4G/4G, 4G/5G and 5G/5G genotypes, respectively. These results demonstrate that the 4G/5G polymorphism of the PAI-1 gene affects the plasma PAI-1 concentration, which could impair fibrinolysis and cause organ failure, and thus the presence of the 4G allele increases the risk of death. Copyright © 2011 S. Karger AG, Basel.

  7. Plasminogen activator inhibitor-2 polymorphism associates with recurrent coronary event risk in patients with high HDL and C-reactive protein levels.

    Directory of Open Access Journals (Sweden)

    James P Corsetti

    Full Text Available The objective of this work was to investigate whether fibrinolysis plays a role in establishing recurrent coronary event risk in a previously identified group of postinfarction patients. This group of patients was defined as having concurrently high levels of high-density lipoprotein cholesterol (HDL-C and C-reactive protein (CRP and was previously demonstrated to be at high-risk for recurrent coronary events. Potential risk associations of a genetic polymorphism of plasminogen activator inhibitor-2 (PAI-2 were probed as well as potential modulatory effects on such risk of a polymorphism of low-density lipoprotein receptor related protein (LRP-1, a scavenger receptor known to be involved in fibrinolysis in the context of cellular internalization of plasminogen activator/plansminogen activator inhibitor complexes. To this end, Cox multivariable modeling was performed as a function of genetic polymorphisms of PAI-2 (SERPINB, rs6095 and LRP-1 (LRP1, rs1800156 as well as a set of clinical parameters, blood biomarkers, and genetic polymorphisms previously demonstrated to be significantly and independently associated with risk in the study population including cholesteryl ester transfer protein (CETP, rs708272, p22phox (CYBA, rs4673, and thrombospondin-4 (THBS4, rs1866389. Risk association was demonstrated for the reference allele of the PAI-2 polymorphism (hazard ratio 0.41 per allele, 95% CI 0.20-0.84, p=0.014 along with continued significant risk associations for the p22phox and thrombospondin-4 polymorphisms. Additionally, further analysis revealed interaction of the LRP-1 and PAI-2 polymorphisms in generating differential risk that was illustrated using Kaplan-Meier survival analysis. We conclude from the study that fibrinolysis likely plays a role in establishing recurrent coronary risk in postinfarction patients with concurrently high levels of HDL-C and CRP as manifested by differential effects on risk by polymorphisms of several genes linked

  8. The role of factors of the hemostasis system and fibrinolysis in the development of gastroesophageal reflux in patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Інна Володимирівна Дудка

    2015-11-01

    Full Text Available Gastroesophageal reflux disease (GERD and chronic obstructive pulmonary disease (COPD belong to common pathological conditions comorbid in 25–60 % of cases.Objective: to find probable mechanisms of GERD progressing against the ground of COPD by means of learning various links of the blood clotting system, anticoagulative blood activity and fibrinolysis for further improvement of the ways to correct the disorders found.Methods. 124 patients with COPD were examined including 90 with comorbid GERD. The control group included 24 practically healthy individuals of an appropriate age and sex. Clinical, biochemical, instrumental and statistical methods of examination were applied.Results. The patients were divided into the following groups: the 1st group – 34 patients with COPD, the 2nd group – 30 patients with COPD with endoscopically negative GERD, the 3rd group – 30 patients with COPD and endoscopically positive non-erosive GERD, the 4th group – 30 patients with COPD and endoscopically positive erosive GERD. The following results were found: while examining coagulation hemostasis – decrease of prothrombin time, fibrinogen content; while examining anticoagulation blood potential – decrease of thrombin time, activity of antithrombin III; while examining fibrinolytic blood activity – inhibition of the total fibrinolytic activity (at the expense of enzymatic activity decrease and compensatory increase of non-enzymatic fibrinolytic activity, decrease of Hageman-dependent fibrinolysis activity.Conclusions. Disorders of coagulation hemostasis, anti-coagulation potential and fibrinolytic blood activity are intensified with the increase of severity of bronchial obstructive syndrome and promote the development of endoscopically positive erosive GERD

  9. The role of clopidogrel in early and sustained arterial patency after fibrinolysis for ST-segment elevation myocardial infarction: the ECG CLARITY-TIMI 28 Study.

    Science.gov (United States)

    Scirica, Benjamin M; Sabatine, Marc S; Morrow, David A; Gibson, C Michael; Murphy, Sabina A; Wiviott, Stephen D; Giugliano, Robert P; McCabe, Carolyn H; Cannon, Christopher P; Braunwald, Eugene

    2006-07-04

    This study was designed to determine the relationship between clopidogrel and early ST-segment resolution (STRes) and the interaction of the two with clinical outcomes after fibrinolysis. ST-segment resolution is an early noninvasive marker of coronary reperfusion. The CLARITY-TIMI 28 (Clopidogrel as Adjunctive Reperfusion Therapy-Thrombolysis in Myocardial Infarction 28) trial randomized 3,491 patients with ST-segment elevation myocardial infarction (STEMI) undergoing fibrinolysis to clopidogrel versus placebo. ST-segment resolution was defined as complete (>70%), partial (30% to 70%), or none (STRes between the clopidogrel and placebo groups at 90 min (38.4% vs. 36.6% at 90 min). When patients were stratified by STRes category, treatment with clopidogrel resulted in greater benefit among those with evidence of early STRes, with greater odds of an open artery at late angiography in patients with partial (odds ratio [OR] 1.4, p = 0.04) or complete (OR 2.0, p STRes, but no improvement in those with no STRes at 90 min (OR 0.89, p = 0.48) (p for interaction = 0.003). Clopidogrel was also associated with a significant reduction in the odds of an in-hospital death or myocardial infarction in patients who achieved partial (OR 0.30, p = 0.003) or complete STRes at 90 min (OR 0.49, p = 0.056), whereas clinical benefit was not apparent in patients who had no STRes (OR 0.98, p = 0.95) (p for interaction = 0.027). By 30 days, the clinical benefit of clopidogrel was predominately seen in patients with complete STRes. Clopidogrel appears to improve late coronary patency and clinical outcomes by preventing reocclusion of open arteries rather than by facilitating early reperfusion.

  10. Enhancing siRNA-based cancer therapy using a new pH-responsive activatable cell-penetrating peptide-modified liposomal system

    Directory of Open Access Journals (Sweden)

    Xiang B

    2017-03-01

    Full Text Available Bai Xiang,1,* Xue-Li Jia,1,* Jin-Long Qi,2 Li-Ping Yang,1 Wei-Hong Sun,1 Xiao Yan,1 Shao-Kun Yang,1 De-Ying Cao,1 Qing Du,1 Xian-Rong Qi3 1Department of Pharmaceutics, School of Pharmaceutical Sciences, 2Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei, 3School of Pharmaceutical Sciences, Peking University, Beijing, China *These authors contributed equally to this work Abstract: As a potent therapeutic agent, small interfering RNA (siRNA has been exploited to silence critical genes involved in tumor initiation and progression. However, development of a desirable delivery system is required to overcome the unfavorable properties of siRNA such as its high degradability, molecular size, and negative charge to help increase its accumulation in tumor tissues and promote efficient cellular uptake and endosomal/lysosomal escape of the nucleic acids. In this study, we developed a new activatable cell-penetrating peptide (ACPP that is responsive to an acidic tumor microenvironment, which was then used to modify the surfaces of siRNA-loaded liposomes. The ACPP is composed of a cell-penetrating peptide (CPP, an acid-labile linker (hydrazone, and a polyanionic domain, including glutamic acid and histidine. In the systemic circulation (pH 7.4, the surface polycationic moieties of the CPP (polyarginine are “shielded” by the intramolecular electrostatic interaction of the inhibitory domain. When exposed to a lower pH, a common property of solid tumors, the ACPP undergoes acid-catalyzed breakage at the hydrazone site, and the consequent protonation of histidine residues promotes detachment of the inhibitory peptide. Subsequently, the unshielded CPP would facilitate the cellular membrane penetration and efficient endosomal/lysosomal evasion of liposomal siRNA. A series of investigations demonstrated that once exposed to an acidic pH, the ACPP-modified liposomes showed elevated cellular uptake, downregulated expression of polo

  11. Plasminogen activator inhibitor 1 4G/5G and -844G/A variants in idiopathic recurrent pregnancy loss.

    Science.gov (United States)

    Magdoud, Kalthoum; Herbepin, Viviana G; Touraine, Renaud; Almawi, Wassim Y; Mahjoub, Touhami

    2013-09-01

    Plasminogen activator inhibitor type 1 (PAI-1) regulates fibrinolysis, and the common promoter region variants -675G/A (4G/5G) and -844G/A are associated with increased thrombotic risk. Despite evidence linking altered fibrinolysis with adverse pregnancy events, including idiopathic recurrent pregnancy loss (RPL), the contribution of PAI-1 variants to RPL risk remains controversial. We investigated the association between the PAI-1 -844G/A and 4G/5G (-675G/A) variants with altered risk of RPL. This was a case-control study involving 304 women with confirmed RPL and 371 age- and ethnically matched control women. PAI-1 genotyping was performed by PCR single-specific primer -675 (G/A) and real-time PCR (-844G/A) analysis. Minor allele frequency (MAF) of 4G/5G (P 5G single-nucleotide polymorphism (SNP) was significantly associated with RPL under additive, dominant, and recessive genetic models; no association of -844G/A with RPL was seen irrespective of the genetic model tested. Taking common -844G/5G haplotype as reference (OR = 1.00), multivariate analysis confirmed the association of 4G-containing -844A/4G (P 5G, but not -844G/A, PAI-1 variant is associated with an increased risk of RPL. © 2013 John Wiley & Sons Ltd.

  12. Long-term outcome of primary angioplasty compared with fibrinolysis across age groups: a Danish Multicenter Randomized Study on Fibrinolytic Therapy Versus Acute Coronary Angioplasty in Acute Myocardial Infarction (DANAMI-2) substudy

    DEFF Research Database (Denmark)

    Fosbøl, Emil Loldrup; Thune, Jens Jakob; Kelbaek, Henning

    2008-01-01

    of angioplasty versus fibrinolysis was investigated in 1,572 patients from the DANAMI-2 study across age groups. End points were total mortality and a composite end point of death, reinfarction, or disabling stroke. Follow-up was 3 years. RESULTS: Increasing age was associated with mortality (adjusted hazard...... ratio [HR] 2.45 per 10 year increment, 95% confidence interval [CI] 1.78-3.37, P age: patients aged ... 0.73, CI 0.41-1.31); 56 to 65 years (HR 0.83, CI 0.52-1.33); 66 to 75 years (HR 0.71, CI 0.48-1.04); and >75 years (HR 0.83, CI 0.59-1.17) (P = .006 for overall treatment effect and P = .5 for interaction between age and treatment). There was no long-term effect of angioplasty versus fibrinolysis...

  13. Comparison of the efficacy of pharmacoinvasive management for ST-segment elevation myocardial infarction in smokers versus non-smokers (from the Trial of Routine Angioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction).

    Science.gov (United States)

    Tan, Nigel S; Goodman, Shaun G; Cantor, Warren J; Tan, Mary K; Yan, Raymond T; Bagnall, Alan J; Mehta, Shamir R; Fitchett, David; Strauss, Bradley H; Yan, Andrew T

    2014-10-01

    Compared with non-smokers, cigarette smokers with ST-segment elevation myocardial infarctions derive greater benefit from fibrinolytic therapy. However, it is not known whether the optimal treatment strategy after fibrinolysis differs on the basis of smoking status. The Trial of Routine Angioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI) randomized patients with ST-segment elevation myocardial infarctions to a routine early invasive (pharmacoinvasive) versus a standard (early transfer only for rescue percutaneous coronary intervention or delayed angiography) strategy after fibrinolysis. The efficacy of these strategies was compared in 1,051 patients on the basis of their smoking status. Treatment heterogeneity was assessed between smokers and non-smokers, and multivariable analysis was performed to evaluate for an interaction between smoking status and treatment strategy after adjusting for baseline Global Registry of Acute Coronary Events (GRACE) risk score. Smokers (n=448) were younger, had fewer cardiovascular risk factors, and had lower GRACE risk scores. They had a lower rate of the primary composite end point of 30-day mortality, reinfarction, recurrent ischemia, heart failure, or cardiogenic shock and fewer deaths or reinfarctions at 6 months and 1 year. Smoking status was not a significant predictor of either primary or secondary end points in multivariable analysis. Pharmacoinvasive management reduced the primary end point compared with standard therapy in smokers (7.7% vs 13.6%, p=0.04) and non-smokers (13.1% vs 19.7%, p=0.03). Smoking status did not modify treatment effect on any measured outcomes (p>0.10 for all). In conclusion, compared with non-smokers, current smokers receiving either standard or early invasive management of ST-segment elevation myocardial infarction after fibrinolysis have more favorable outcomes, which is likely attributable to their better baseline risk profile. The

  14. Laboratory assessment of anti-thrombotic therapy in heart failure, atrial fibrillation and coronary artery disease: insights using thrombelastography and a micro-titre plate assay of thrombogenesis and fibrinolysis

    OpenAIRE

    Lau, Y. C.; Xiong, Q.; Ranjit, P.; Lip, G. Y. H.; Blann, A. D.

    2016-01-01

    As heart failure, coronary artery disease and atrial fibrillation all bring a risk of thrombosis, anti-thrombotic therapy is recommended. Despite such treatment, major cardiovascular events such as myocardial infarction and stroke still occur, implying inadequate suppression of thrombus formation. Accordingly, identification of patients whose haemostasis remains unimpaired by treatment is valuable. We compared indices for assessing thrombogenesis and fibrinolysis by two different techniques i...

  15. Should anti-inhibitor coagulant complex and tranexamic acid be used concomitantly?

    Science.gov (United States)

    Valentino, L A; Holme, P A

    2015-11-01

    Inhibitor development in haemophilia patients is challenging especially when undergoing surgical procedures. The development of an inhibitor precludes using factor VIII (FVIII) therapy thereby requiring a bypassing agent (BPA) for surgical bleeding prophylaxis if the FVIII inhibitor titre >5 BU. Concomitant use of anti-inhibitor coagulant complex (AICC) and tranexamic acid has been reported in the literature as a beneficial treatment for this population. Anti-inhibitor coagulant complex is known to cause an increase in thrombin generation and tranexamic acid inhibits fibrinolysis. Hence, the combined used of AICC and tranexamic acid has been limited due to safety concerns over possibilities of increased risk of thrombotic events and disseminated intravascular coagulation. However, the rationale for concomitant therapy is to obtain a potential synergistic effect and to increase clot stability. We conducted a literature review of past studies and individual case reports of concomitant use of AICC and tranexamic acid, which was extensively used during dental procedures. Evidence also exists for concomitant use of the combined therapy in orthopaedic procedures, control of gastrointestinal bleeding, epistaxis and cerebral haemorrhages. Some patients who received the combined therapy had failed monotherapy with a single BPA prior to combined therapy. There were no reports of thrombotic complications related to the concomitant therapy and haemostasis was achieved in all cases. Anti-inhibitor coagulant complex and tranexamic acid therapy was found to be safe, well-tolerated and effective therapy in haemophilia patients with inhibitors. Additional randomized controlled studies should be performed to confirm these findings. © 2015 John Wiley & Sons Ltd.

  16. The Comparison of the Outcomes between Primary PCI, Fibrinolysis, and No Reperfusion in Patients ≥ 75 Years Old with ST-Segment Elevation Myocardial Infarction: Results from the Chinese Acute Myocardial Infarction (CAMI Registry.

    Directory of Open Access Journals (Sweden)

    He Peiyuan

    Full Text Available Only a few randomized trials have analyzed the clinical outcomes of elderly ST-segment elevation myocardial infarction (STEMI patients (≥ 75 years old. Therefore, the best reperfusion strategy has not been well established. An observational study focused on clinical outcomes was performed in this population.Based on the national registry on STEMI patients, the in-hospital outcomes of elderly patients with different reperfusion strategies were compared. The primary endpoint was defined as death. Secondary endpoints included recurrent myocardial infarction, ischemia driven revascularization, myocardial infarction related complications, and major bleeding. Multivariable regression analysis was performed to adjust for the baseline disparities between the groups.Patients who had primary percutaneous coronary intervention (PCI or fibrinolysis were relatively younger. They came to hospital earlier, and had lower risk of death compared with patients who had no reperfusion. The guideline recommended medications were more frequently used in patients with primary PCI during the hospitalization and at discharge. The rates of death were 7.7%, 15.0%, and 19.9% respectively, with primary PCI, fibrinolysis, and no reperfusion (P 0.05. In the multivariable regression analysis, primary PCI outweighs no reperfusion in predicting the in-hospital death in patients ≥ 75 years old. However, fibrinolysis does not.Early reperfusion, especially primary PCI was safe and effective with absolute reduction of mortality compared with no reperfusion. However, certain randomized trials were encouraged to support the conclusion.

  17. Return to normal of sup(99m)Tc-plasmin test after deep venous thrombosis and its relationship to vessel wall fibrinolysis

    Energy Technology Data Exchange (ETDEWEB)

    Edenbrandt, C.M.; Hedner, U.; Tengborn, L.; Nilsson, J.; Ohlin, P.

    1986-08-01

    Fourteen patients with deep venous thrombosis (DVT) and a positive sup(99m)Tc-plasmin test were followed up to determine how soon a negative test was obtained. Localization and extension of the thrombi were determined by phlebography. Plasminogen activator activity in vein walls and local fibrinolytic activity after venous occlusion were measured in order to find out what the prerequisites for impaired thrombolysis are. The time required to obtain a negative sup(99m)Tc-plasmin test showed considerable variation, ranging from less than 1 week to more than 6 months. The sup(99m)Tc-plasmin test had returned to normal in 64% of the patients after 6 months. No relationship was found between vessel wall fibrinolysis and time to normalization. Instead, we found an association between the time to normalization of the sup(99m)Tc-plasmin test and the size of the thrombus, according to phlebography, as well as between the time to normalization of the sup(99m)Tc-plasmin test and the extension of leg points with a positive sup(99m)Tc-plasmin test at admission. The finding of abnormal sup(99m)Tc-plasmin test results more than 6 months after acute DVT is of practical importance and warrants caution when evaluating patients with symptoms and signs suggestive of acute recurrent DVT.

  18. Outcome after local intra-arterial fibrinolysis compared with the natural course of patients with a dense middle cerebral artery on early CT

    International Nuclear Information System (INIS)

    Bendszus, M.; Urbach, H.; Solymosi, L.; Ries, F.

    1998-01-01

    Our purpose was to relate the outcome after local intra-arterial fibrinolysis (LIF) to the natural course in middle cerebral artery (MCA) occlusion. We retrospectively studied 40 patients with a dense middle cerebral artery on early CT; 20 were treated with LIF within 6 h of onset of symptoms, 20 received ''conventional'' stroke therapy. The dense middle cerebral artery, which is regarded as a highly specific indicator of thromboembolic MCA occlusion, was chosen as inclusion criterion since patients with ''conventional'' stroke therapy were not exposed to cerebral angiography. Patients treated with LIF had a significantly better outcome using the Barthel index (P = 0.025): there was a 30 % increase in the proportion of patients with minimal or no disability. Mortality, however, did not differ significantly (P = 0.7). Two fatal haemorrhages occurred in the LIF group, and one haemorrhagic transformation in the ''conventional'' group. Leptomeningeal collateralisation correlated significantly with outcome in the LIF group (P = 0.04). Although the relation between outcome and interval from onset of symptoms to LIF was not significant (P = 0.74), all patients treated within 3 h had an excellent outcome. (orig.)

  19. Plasminogen Activator Inhibitor-1 Controls Vascular Integrity by Regulating VE-Cadherin Trafficking.

    Directory of Open Access Journals (Sweden)

    Anna E Daniel

    Full Text Available Plasminogen activator inhibitor-1 (PAI-1, a serine protease inhibitor, is expressed and secreted by endothelial cells. Patients with PAI-1 deficiency show a mild to moderate bleeding diathesis, which has been exclusively ascribed to the function of PAI-1 in down-regulating fibrinolysis. We tested the hypothesis that PAI-1 function plays a direct role in controlling vascular integrity and permeability by keeping endothelial cell-cell junctions intact.We utilized PAI-039, a specific small molecule inhibitor of PAI-1, to investigate the role of PAI-1 in protecting endothelial integrity. In vivo inhibition of PAI-1 resulted in vascular leakage from intersegmental vessels and in the hindbrain of zebrafish embryos. In addition PAI-1 inhibition in human umbilical vein endothelial cell (HUVEC monolayers leads to a marked decrease of transendothelial resistance and disrupted endothelial junctions. The total level of the endothelial junction regulator VE-cadherin was reduced, whereas surface VE-cadherin expression was unaltered. Moreover, PAI-1 inhibition reduced the shedding of VE-cadherin. Finally, we detected an accumulation of VE-cadherin at the Golgi apparatus.Our findings indicate that PAI-1 function is important for the maintenance of endothelial monolayer and vascular integrity by controlling VE-cadherin trafficking to and from the plasma membrane. Our data further suggest that therapies using PAI-1 antagonists like PAI-039 ought to be used with caution to avoid disruption of the vessel wall.

  20. Glycosaminoglycans affect the interaction of human plasma kallikrein with plasminogen, factor XII and inhibitors

    Directory of Open Access Journals (Sweden)

    Gozzo A.J.

    2003-01-01

    Full Text Available Human plasma kallikrein, a serine proteinase, plays a key role in intrinsic blood clotting, in the kallikrein-kinin system, and in fibrinolysis. The proteolytic enzymes involved in these processes are usually controlled by specific inhibitors and may be influenced by several factors including glycosaminoglycans, as recently demonstrated by our group. The aim of the present study was to investigate the effect of glycosaminoglycans (30 to 250 µg/ml on kallikrein activity on plasminogen and factor XII and on the inhibition of kallikrein by the plasma proteins C1-inhibitor and antithrombin. Almost all available glycosaminoglycans (heparin, heparan sulfate, bovine and tuna dermatan sulfate, chondroitin 4- and 6-sulfates reduced (1.2 to 3.0 times the catalytic efficiency of kallikrein (in a nanomolar range on the hydrolysis of plasminogen (0.3 to 1.8 µM and increased (1.9 to 7.7 times the enzyme efficiency in factor XII (0.1 to 10 µM activation. On the other hand, heparin, heparan sulfate, and bovine and tuna dermatan sulfate improved (1.2 to 3.4 times kallikrein inhibition by antithrombin (1.4 µM, while chondroitin 4- and 6-sulfates reduced it (1.3 times. Heparin and heparan sulfate increased (1.4 times the enzyme inhibition by the C1-inhibitor (150 nM.

  1. Plasmin substrate binding site cooperativity guides the design of potent peptide aldehyde inhibitors.

    Science.gov (United States)

    Swedberg, Joakim E; Harris, Jonathan M

    2011-10-04

    Perioperative bleeding is a cause of major blood loss and is associated with increased rates of postoperative morbidity and mortality. To combat this, antifibrinolytic inhibitors of the serine protease plasmin are commonly used to reduce bleeding during surgery. The most effective and previously widely used of these is the broad range serine protease inhibitor aprotinin. However, adverse clinical outcomes have led to use of alternative serine lysine analogues to inhibit plasmin. These compounds suffer from low selectivity and binding affinity. Consequently, a concerted effort to discover potent and selective plasmin inhibitors has developed. This study used a noncombinatorial peptide library to define plasmin's extended substrate specificity and guide the design of potent transition state analogue inhibitors. The various substrate binding sites of plasmin were found to exhibit a higher degree of cooperativity than had previously been appreciated. Peptide sequences capitalizing on these features produced high-affinity inhibitors of plasmin. The most potent of these, Lys-Met(sulfone)-Tyr-Arg-H [KM(O(2))YR-H], inhibited plasmin with a K(i) of 3.1 nM while maintaining 25-fold selectivity over plasma kallikrein. Furthermore, 125 nM (0.16 μg/mL) KM(O(2))YR-H attenuated fibrinolysis in vitro with an efficacy similar to that of 15 nM (0.20 μg/mL) aprotinin. To date, this is the most potent peptide inhibitor of plasmin that exhibits selectivity against plasma kallikrein, making this compound an attractive candidate for further therapeutic development.

  2. Freeze-dried plasma enhances clot formation and inhibits fibrinolysis in the presence of tissue plasminogen activator similar to pooled liquid plasma.

    Science.gov (United States)

    Huebner, Benjamin R; Moore, Ernest E; Moore, Hunter B; Sauaia, Angela; Stettler, Gregory; Dzieciatkowska, Monika; Hansen, Kirk; Banerjee, Anirban; Silliman, Christopher C

    2017-08-01

    Systemic hyperfibrinolysis is an integral part of trauma-induced coagulopathy associated with uncontrolled bleeding. Recent data suggest that plasma-first resuscitation attenuates hyperfibrinolysis; however, the availability, transport, storage, and administration of plasma in austere environments remain challenging and have limited its use. Freeze-dried plasma (FDP) is a potential alternative due to ease of storage, longer shelf life, and efficient reconstitution. FDP potentially enhances clot formation and resists breakdown better than normal saline (NS) and albumin and similar to liquid plasma. Healthy volunteers underwent citrated blood draw followed by 50% dilution with NS, albumin, pooled plasma (PP), or pooled freeze-dried plasma (pFDP). Citrated native and tissue plasminogen activator (t-PA)-challenge (75 ng/mL) thrombelastography were done. Proteins in PP, pFDP, and albumin were analyzed by mass spectroscopy. pFDP and PP had superior clot-formation rates (angle) and clot strength (maximum amplitude) compared with NS and albumin in t-PA-challenge thrombelastographies (angle: pFDP, 67.9 degrees; PP, 67.8 degrees; NS, 40.6 degrees; albumin, 35.8 degrees; maximum amplitude: pFDP, 62.4 mm; PP, 63.5 mm; NS, 44.8 mm; albumin, 41.1 mm). NS and albumin dilution increased susceptibility to t-PA-induced hyperfibrinolysis compared with pFDP and PP (NS, 62.4%; albumin, 62.6%; PP, 8.5%; pFDP, 6.7%). pFDP was similar to PP in the attenuation of t-PA-induced fibrinolysis. Most proteins (97%) were conserved during the freeze-dry process, with higher levels in 12% of pFDP proteins compared with PP. pFDP enhances clot formation and attenuates hyperfibrinolysis better than NS and albumin and is a potential alternative to plasma resuscitation in the treatment of hemorrhagic shock. © 2017 AABB.

  3. Comparison of the effects of spinal epidural and general anesthesia on coagulation and fibrinolysis in laparoscopic cholecystectomy: a randomized controlled trial: VSJ Competition, 2nd place.

    Science.gov (United States)

    Demiryas, Suleyman; Donmez, Turgut; Erdem, Vuslat Muslu; Erdem, Duygu Ayfer; Hatipoglu, Engin; Ferahman, Sina; Sunamak, Oguzhan; Zengin, Lale Yoldas; Kocakusak, Ahmet

    2017-09-01

    Laparoscopic cholecystectomy (LC) is usually performed under general anesthesia. Recently, laparoscopic cholecystectomy under regional anesthesia has become popular, but this creates a serious risk of thromboembolism because of pneumoperitoneum, anesthesia technique, operative positioning, and patient-specific risk factors. This randomized controlled trial compares the effects of two different anesthesia techniques in laparoscopic cholecystectomy on coagulation and fibrinolysis. This randomized prospective study included 60 low-risk patients with deep vein thrombosis (DVT) who underwent elective LC without thrombo-emboli prophylaxis. The patients were randomly divided into two groups according to the anesthesia technique: the general anesthesia (group 1, n = 30) and spinal epidural anesthesia (group 2, n = 30) groups. Measurement of the prothrombin time (PT), thrombin time (TT), international normalized ratio (INR), activated partial thromboplastin time (aPTT), and blood levels of D-dimer (DD) and fibrinogen (F) were recorded preoperatively (pre), at the first hour (post 1) and 24 h (post 24) after the surgery. These results were compared both between and within the groups. The mean age was 51.5 ±16.7 years (range: 19-79 years). Pneumoperitoneum time was similar between group 1 (33.8 ±7.8) and group 2 (34.8 ±10.4). The TT levels significantly declined postoperatively in both groups. The levels of PT, aPTT, INR, D-dimer and fibrinogen dramatically increased postoperatively in both groups. While there was not any DVT, there was a significant decline in TT. There was a dramatic rise in the PT, INR, D-dimer, fibrin degradation products (FDP), and fibrinogen following LC. This may be attributed to the effects of pneumoperitoneum and anesthesia techniques on portal vein flow.

  4. Effect of tranexamic acid on coagulation and fibrinolysis in women with postpartum haemorrhage (WOMAN-ETAC: protocol and statistical analysis plan for a randomized controlled trial [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Haleema Shakur

    2016-12-01

    Full Text Available Background: Postpartum haemorrhage (PPH is a leading cause of maternal death. Tranexamic acid has the potential to reduce bleeding and a large randomized controlled trial of its effect on maternal health outcomes in women with PPH (The WOMAN trial is ongoing. We will examine the effect of tranexamic acid on fibrinolysis and coagulation in a subset of WOMAN trial participants.   Methods. Adult women with clinically diagnosed primary PPH after vaginal or caesarean delivery are eligible for inclusion in the WOMAN trial. In a sub-group of trial participants, blood samples will be collected at baseline and 30 minutes after the first dose of tranexamic acid or matching placebo.  Our primary objective is to evaluate the effect of tranexamic acid on fibrinolysis. Fibrinolysis will be assessed by measuring D-dimers and by rotational thromboelastometry (ROTEM. Secondary outcomes are international normalized ratio (INR, prothrombin time (PT, activated partial thromboplastin time (APTT, fibrinogen, haemoglobin and platelets. We aim to include about 180 women from the University College Hospital, Ibadan in Nigeria.   Discussion:  This sub-study of WOMAN trial participants should provide information on the mechanism of action of tranexamic acid in women with postpartum haemorrhage. We present the trial protocol and statistical analysis plan. The trial protocol was registered prior to the start of patient recruitment. The statistical analysis plan was completed before un-blinding.     Trial registration: The trial was registered: ClinicalTrials.gov, Identifier NCT00872469 https://clinicaltrials.gov/ct2/show/NCT00872469; ISRCTN registry, Identifier   ISRCTN76912190 http://www.isrctn.com/ISRCTN76912190 (Registration date: 22/03/2012.

  5. Laboratory assessment of anti-thrombotic therapy in heart failure, atrial fibrillation and coronary artery disease: insights using thrombelastography and a micro-titre plate assay of thrombogenesis and fibrinolysis.

    Science.gov (United States)

    Lau, Y C; Xiong, Q; Ranjit, P; Lip, G Y H; Blann, A D

    2016-08-01

    As heart failure, coronary artery disease and atrial fibrillation all bring a risk of thrombosis, anti-thrombotic therapy is recommended. Despite such treatment, major cardiovascular events such as myocardial infarction and stroke still occur, implying inadequate suppression of thrombus formation. Accordingly, identification of patients whose haemostasis remains unimpaired by treatment is valuable. We compared indices for assessing thrombogenesis and fibrinolysis by two different techniques in patients on different anti-thrombotic agents, i.e. aspirin or warfarin. We determined fibrin clot formation and fibrinolysis by a microplate assay and thromboelastography, and platelet marker soluble P selectin in 181 patients with acute or chronic heart failure, coronary artery disease who were taking either aspirin or warfarin. Five thromboelastograph indices and four microplate assay indices were different on aspirin versus warfarin (p indices rate of clot formation and rate of clot dissolution were independently related to aspirin or warfarin use (p ≤ 0.001). Five microplate assay indices, but no thrombelastograph index, were different (p indices were different (p ≤ 0.002) in warfarin users. The microplate assay indices of lag time and rate of clot formation were abnormal in chronic heart failure patients on aspirin, suggesting increased risk of thrombosis despite anti-platelet use. Soluble P selectin was lower in patients on aspirin (p = 0.0175) but failed to correlate with any other index of haemostasis. The microplate assay shows promise as a tool for dissecting thrombogenesis and fibrinolysis in cardiovascular disease, and the impact of antithrombotic therapy. Prospective studies are required to determine a role in predicting thrombotic risk.

  6. Comprehensive identification of genes driven by ERV9-LTRs reveals TNFRSF10B as a re-activatable mediator of testicular cancer cell death

    Science.gov (United States)

    Beyer, U; Krönung, S K; Leha, A; Walter, L; Dobbelstein, M

    2016-01-01

    The long terminal repeat (LTR) of human endogenous retrovirus type 9 (ERV9) acts as a germline-specific promoter that induces the expression of a proapoptotic isoform of the tumor suppressor homologue p63, GTAp63, in male germline cells. Testicular cancer cells silence this promoter, but inhibitors of histone deacetylases (HDACs) restore GTAp63 expression and give rise to apoptosis. We show here that numerous additional transcripts throughout the genome are driven by related ERV9-LTRs. 3' Rapid amplification of cDNA ends (3'RACE) was combined with next-generation sequencing to establish a large set of such mRNAs. HDAC inhibitors induce these ERV9-LTR-driven genes but not the LTRs from other ERVs. In particular, a transcript encoding the death receptor DR5 originates from an ERV9-LTR inserted upstream of the protein coding regions of the TNFRSF10B gene, and it shows an expression pattern similar to GTAp63. When treating testicular cancer cells with HDAC inhibitors as well as the death ligand TNF-related apoptosis-inducing ligand (TRAIL), rapid cell death was observed, which depended on TNFRSF10B expression. HDAC inhibitors also cooperate with cisplatin (cDDP) to promote apoptosis in testicular cancer cells. ERV9-LTRs not only drive a large set of human transcripts, but a subset of them acts in a proapoptotic manner. We propose that this avoids the survival of damaged germ cells. HDAC inhibition represents a strategy of restoring the expression of a class of ERV9-LTR-mediated genes in testicular cancer cells, thereby re-enabling tumor suppression. PMID:26024393

  7. Human Kunitz-type protease inhibitor engineered for enhanced matrix retention extends longevity of fibrin biomaterials.

    Science.gov (United States)

    Briquez, Priscilla S; Lorentz, Kristen M; Larsson, Hans M; Frey, Peter; Hubbell, Jeffrey A

    2017-08-01

    Aprotinin is a broad-spectrum serine protease inhibitor used in the clinic as an anti-fibrinolytic agent in fibrin-based tissue sealants. However, upon re-exposure, some patients suffer from hypersensitivity immune reactions likely related to the bovine origin of aprotinin. Here, we aimed to develop a human-derived substitute to aprotinin. Based on sequence homology analyses, we identified the Kunitz-type protease inhibitor (KPI) domain of human amyloid-β A4 precursor protein as being a potential candidate. While KPI has a lower intrinsic anti-fibrinolytic activity than aprotinin, we reasoned that its efficacy is additionally limited by its fast release from fibrin material, just as aprotinin's is. Thus, we engineered KPI variants for controlled retention in fibrin biomaterials, using either covalent binding through incorporation of a substrate for the coagulation transglutaminase Factor XIIIa or through engineering of extracellular matrix protein super-affinity domains for sequestration into fibrin. We showed that both engineered KPI variants significantly slowed plasmin-mediated fibrinolysis in vitro, outperforming aprotinin. In vivo, our best engineered KPI variant (incorporating the transglutaminase substrate) extended fibrin matrix longevity by 50%, at a dose at which aprotinin did not show efficacy, thus qualifying it as a competitive substitute of aprotinin in fibrin sealants. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  8. Monoamine Oxidase Inhibitors (MAOIs)

    Science.gov (United States)

    ... health-medications/index.shtml. Accessed May 16, 2016. Hirsch M, et al. Monoamine oxidase inhibitors (MAOIs) for ... www.uptodate.com/home. Accessed May 16, 2016. Hirsch M, et al. Discontinuing antidepressant medications in adults. ...

  9. THROMBOPHILIA IN PREGNANCY – CURRENT ISSUE OF MODERN PERINATOLOGY

    Directory of Open Access Journals (Sweden)

    Dragana Radović-Janošević

    2015-09-01

    Full Text Available Pregnancy is a condition of increased affinity to blood clotting. The most important changes of coagulation system in pregnancy involve the increase of the following coagulation factors: fibrinogen production, level of numerous blood coagulation factors- FII, FVII, FVIII, FX, FXII, acquired activated protein C resistance, and the decrease of: fibrinolysis due to the increase of a large number of fibrinolytic activator inhibitors PAI-1 and PAI-2, thrombin activatable fibrinolysis inhibitor TAFI, and levels of proteins S and C. This disease is not a disease on its own, but a group of inherited and acquired coagulation disorders that increase the predisposition to thrombosis. The treatment of choice in pregnancy are low-molecular-weight heparins (LMWHs which are derived from standard heparin by controlled hydrolysis, thus obtaining heparins of a lower molecular mass. The most commonly used LMWHs are: dalteparin sodium, enoxaparin, nadroparin-calcium, reviparin. LMWH is given in prophylactic doses – low and medium doses in therapeutic doses. Thromboprophylaxis in pregnancy is implemented as: intrapartal, intra- and postpartum according to the official recommendations of the American Association of Obstetricians and Gynecologists (ACOG. Specific recommendations of ACOG refer to the treatment of hereditary thrombophilia in pregnancy.

  10. Hemostasis in Overt and Subclinical Hyperthyroidism

    Science.gov (United States)

    Ordookhani, Arash; Burman, Kenneth D.

    2017-01-01

    Context There are contradictory results on the effect of hyperthyroidism on hemostasis. Inadequate population-based studies limited their clinical implications, mainly on the risk of venous thromboembolism (VTE). The present review focuses on hemostatic changes in overt and subclinical hyperthyroidism. Methods A systematic literature search was conducted employing MEDLINE database. The following words were used for the search: Hyperthyroidism; thyrotoxicosis; Graves disease; goiter, nodular; hemostasis; blood coagulation factors; blood coagulation disorders; venous thromboembolism; bleeding; fibrinolysis. The articles that were related to hyperthyroidism and hemostasis are used in this manuscript. Results Hyperthyroidism, either overt or subclinical, renders a hypercoagulable state, although there are several studies with contradictory findings in the literature. Hypercoagulability may be caused by an increase in the level of various coagulation factors such as factor (F) VIII, FX, FIX, von Willebrand F (vWF), and fibrinogen, while hypofibrinolysis by changes in coagulation parameters such as a decrease in plasmin and plasmin activator or an increase in α2-antiplasmin, plasminogen activator inhibitor-1 and thrombin activatable fibrinolysis inhibitor Conclusions Although many reports are in favor of a hypercoagulable state in overt hyperthyroidism but this finding at the biochemical level and its clinical implication, on the occurrence of VTE, has yet to be confirmed. PMID:29201071

  11. Plasminogen Activator Inhibitor-1 (PAI-1) gene 4G/5G alleles frequency distribution in the Lebanese population.

    Science.gov (United States)

    Shammaa, Dina M R; Sabbagh, Amira S; Taher, Ali T; Zaatari, Ghazi S; Mahfouz, Rami A R

    2008-09-01

    Plasminogen activator inhibitor-1 (PAI-1) is an inhibitor of fibrinolysis. Increased plasma PAI-1 levels play an essential role in the pathogenesis of cardiovascular risk and other diseases associated with thrombosis. The 4G/5G polymorphism of the PAI-1 promoter region has been extensively studied in different populations. We studied 160 healthy unrelated Lebanese individuals using a reverse hybridization PCR assay to detect the 5G/5G, 4G/5G and, 4G/4G genotypes of the PAI-1 gene and the frequencies of the 4G and 5G alleles. We found that 4G/5G genotype was the most prevalent (45.6%) followed by 5G/5G (36.9%) and 4G/4G (17.5%). The frequencies of the 4G and 5G alleles were calculated to be 0.403 and 0.597, respectively. Compared to other ethnic communities, the Lebanese population was found to harbour a relatively high prevalence of the rare 4G allele. This, in turn, may predispose this population to develop cardiovascular diseases and other thrombotic clinical conditions. This study aids to enhance our understanding of the genetic features of the Lebanese population.

  12. SGLT2 inhibitors.

    Science.gov (United States)

    Dardi, I; Kouvatsos, T; Jabbour, S A

    2016-02-01

    Diabetes mellitus is a serious health issue and an economic burden, rising in epidemic proportions over the last few decades worldwide. Although several treatment options are available, only half of the global diabetic population achieves the recommended or individualized glycemic targets. Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of antidiabetic agents with a novel insulin-independent action. SGLT2 is a transporter found in the proximal renal tubules, responsible for the reabsorption of most of the glucose filtered by the kidney. Inhibition of SGLT2 lowers the blood glucose level by promoting the urinary excretion of excess glucose. Due to their insulin-independent action, SGLT2 inhibitors can be used with any degree of beta-cell dysfunction or insulin resistance, related to a very low risk of hypoglycemia. In addition to improving glycemic control, SGLT2 inhibitors have been associated with a reduction in weight and blood pressure when used as monotherapy or in combination with other antidiabetic agents in patients with type 2 diabetes mellitus (T2DM). Treatment with SGLT2 inhibitors is usually well tolerated; however, they have been associated with an increased incidence of urinary tract and genital infections, although these infections are usually mild and easy to treat. SGLT2 inhibitors are a promising new option in the armamentarium of drugs for patients with T2DM. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Aromatase inhibitors in pediatrics.

    Science.gov (United States)

    Wit, Jan M; Hero, Matti; Nunez, Susan B

    2011-10-25

    Aromatase, an enzyme located in the endoplasmic reticulum of estrogen-producing cells, catalyzes the rate-limiting step in the conversion of androgens to estrogens in many tissues. The clinical features of patients with defects in CYP19A1, the gene encoding aromatase, have revealed a major role for this enzyme in epiphyseal plate closure, which has promoted interest in the use of inhibitors of aromatase to improve adult height. The availability of the selective aromatase inhibitors letrozole and anastrozole--currently approved as adjuvant therapy for breast cancer--have stimulated off-label use of aromatase inhibitors in pediatrics for the following conditions: hyperestrogenism, such as aromatase excess syndrome, Peutz-Jeghers syndrome, McCune-Albright syndrome and functional follicular ovarian cysts; hyperandrogenism, for example, testotoxicosis (also known as familial male-limited precocious puberty) and congenital adrenal hyperplasia; pubertal gynecomastia; and short stature and/or pubertal delay in boys. Current data suggest that aromatase inhibitors are probably effective in the treatment of patients with aromatase excess syndrome or testotoxicosis, partially effective in Peutz-Jeghers and McCune-Albright syndrome, but probably ineffective in gynecomastia. Insufficient data are available in patients with congenital adrenal hyperplasia or functional ovarian cysts. Although aromatase inhibitors appear effective in increasing adult height of boys with short stature and/or pubertal delay, safety concerns, including vertebral deformities, a decrease in serum HDL cholesterol levels and increase of erythrocytosis, are reasons for caution.

  14. JAK inhibitors in autoinflammation.

    Science.gov (United States)

    Hoffman, Hal M; Broderick, Lori

    2018-06-11

    Interferonopathies are a subset of autoinflammatory disorders with a prominent type I IFN gene signature. Treatment of these patients has been challenging, given the lack of response to common autoinflammatory therapeutics including IL-1 and TNF blockade. JAK inhibitors (Jakinibs) are a family of small-molecule inhibitors that target the JAK/STAT signaling pathway and have shown clinical efficacy, with FDA and European Medicines Agency (EMA) approval for arthritic and myeloproliferative syndromes. Sanchez and colleagues repurposed baricitinib to establish a significant role for JAK inhibition as a novel therapy for patients with interferonopathies, demonstrating the power of translational rare disease research with lifesaving effects.

  15. Cathepsin D inhibitors

    Directory of Open Access Journals (Sweden)

    M. Gacko

    2007-11-01

    Full Text Available Inhibitors of cathepsin D belong to chemical compounds that estrify carboxyl groups of the Asp33 and Asp231residues of its catalytic site, penta-peptides containing statin, i.e. the amino acid similar in structure to the tetraedric indirectproduct, and polypeptides found in the spare organs of many plants and forming permanent noncovalent complexes withcathepsin. Cathepsin D activity is also inhibited by alpha2-macroglobulin and antibodies directed against this enzyme.Methods used to determine the activity and concentration of these inhibitors and their analytical, preparative and therapeuticapplications are discussed.

  16. Transglutaminase inhibitor from milk

    NARCIS (Netherlands)

    Jong, G.A.H. de; Wijngaards, G.; Koppelman, S.J.

    2003-01-01

    Cross-linking experiments of skimmed bovine milk with bacterial transglutaminase isolated from Streptoverticillium mobaraense showed only some degree of formation of high-molecular-weight casein polymers. Studies on the nature of this phenomenon revealed that bovine milk contains an inhibitor of

  17. Inhibitors of histone demethylases

    DEFF Research Database (Denmark)

    Lohse, Brian; Kristensen, Jesper L; Kristensen, Line H

    2011-01-01

    Methylated lysines are important epigenetic marks. The enzymes involved in demethylation have recently been discovered and found to be involved in cancer development and progression. Despite the relative recent discovery of these enzymes a number of inhibitors have already appeared. Most of the i...

  18. Plasminogen activator inhibitor type 1 regulates microglial motility and phagocytic activity

    Directory of Open Access Journals (Sweden)

    Jeon Hyejin

    2012-06-01

    Full Text Available Abstract Background Plasminogen activator inhibitor type 1 (PAI-1 is the primary inhibitor of urokinase type plasminogen activators (uPA and tissue type plasminogen activators (tPA, which mediate fibrinolysis. PAI-1 is also involved in the innate immunity by regulating cell migration and phagocytosis. However, little is known about the role of PAI-1 in the central nervous system. Methods In this study, we identified PAI-1 in the culture medium of mouse mixed glial cells by liquid chromatography and tandem mass spectrometry. Secretion of PAI-1 from glial cultures was detected by ELISA and western blotting analysis. Cell migration was evaluated by in vitro scratch-wound healing assay or Boyden chamber assay and an in vivo stab wound injury model. Phagocytic activity was measured by uptake of zymosan particles. Results The levels of PAI-1 mRNA and protein expression were increased by lipopolysaccharide and interferon-γ stimulation in both microglia and astrocytes. PAI-1 promoted the migration of microglial cells in culture via the low-density lipoprotein receptor-related protein (LRP 1/Janus kinase (JAK/signal transducer and activator of transcription (STAT1 axis. PAI-1 also increased microglial migration in vivo when injected into mouse brain. PAI-1-mediated microglial migration was independent of protease inhibition, because an R346A mutant of PAI-1 with impaired PA inhibitory activity also promoted microglial migration. Moreover, PAI-1 was able to modulate microglial phagocytic activity. PAI-1 inhibited microglial engulfment of zymosan particles in a vitronectin- and Toll-like receptor 2/6-dependent manner. Conclusion Our results indicate that glia-derived PAI-1 may regulate microglial migration and phagocytosis in an autocrine or paracrine manner. This may have important implications in the regulation of brain microglial activities in health and disease.

  19. Plasminogen activator inhibitor-1 is elevated in patients with COPD independent of metabolic and cardiovascular function

    Science.gov (United States)

    Waschki, Benjamin; Watz, Henrik; Holz, Olaf; Magnussen, Helgo; Olejnicka, Beata; Welte, Tobias; Rabe, Klaus F; Janciauskiene, Sabina

    2017-01-01

    Introduction Plasminogen activator inhibitor-1 (PAI-1), a major inhibitor of fibrinolysis, is associated with thrombosis, obesity, insulin resistance, dyslipidemia, and premature aging, which all are coexisting conditions of chronic obstructive pulmonary disease (COPD). The role of PAI-1 in COPD with respect to metabolic and cardiovascular functions is unclear. Methods In this study, which was nested within a prospective cohort study, the serum levels of PAI-1 were cross-sectionally measured in 74 stable COPD patients (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Stages I–IV) and 18 controls without lung disease. In addition, triglycerides, high-density lipoprotein cholesterol, fasting plasma glucose, waist circumference, blood pressure, smoking status, high-sensitive C-reactive protein (hs-CRP), adiponectin, ankle–brachial index, N-terminal pro-B-type natriuretic peptide, and history of comorbidities were also determined. Results The serum levels of PAI-1 were significantly higher in COPD patients than in controls, independent of a broad spectrum of possible confounders including metabolic and cardiovascular dysfunction. A multivariate regression analysis revealed triglyceride and hs-CRP levels to be the best predictors of PAI-1 within COPD. GOLD Stages II and III remained independently associated with higher PAI-1 levels in a final regression analysis. Conclusion The data from the present study showed that the serum levels of PAI-1 are higher in patients with COPD and that moderate-to-severe airflow limitation, hypertriglyceridemia, and systemic inflammation are independent predictors of an elevated PAI-1 level. PAI-1 may be a potential biomarker candidate for COPD-specific and extra-pulmonary manifestations. PMID:28356730

  20. Elevated NT-proBNP is associated with unfavorably altered plasma fibrin clot properties in atrial fibrillation.

    Science.gov (United States)

    Matusik, Paweł T; Matusik, Patrycja S; Kornacewicz-Jach, Zdzisława; Małecka, Barbara; Ząbek, Andrzej; Undas, Anetta

    2017-09-15

    Dense fibrin clot formation and hypofibrinolysis have been reported in atrial fibrillation (AF). It is unclear which factors affect fibrin clot properties in AF. We investigated plasma fibrin clot permeability (K s ), clot lysis time (CLT), endogenous thrombin potential (ETP) as well as other coagulation and fibrinolysis parameters along with N-terminal pro-B-type natriuretic peptide (NT-proBNP) in 160 AF patients (median age, 70.5years). Previous stroke (n=15; 9.4%) was associated with decreased K s (P=0.04) and longer CLT (P=0.005), together with higher antiplasmin (P=0.03) and lower tissue-type plasminogen activator (P=0.01). Lower K s (P=0.04) and tendency towards longer CLT (P=0.10) were observed in patients with a left atrium diameter>40mm. Patients with a CHA 2 DS 2 -VASc score of 3 or more (82.5%) were characterized by higher thrombin-activatable fibrinolysis inhibitor antigen (P=0.009). K s was inversely correlated with log NT-proBNP (r=-0.34, PCLT was positively correlated with log NT-proBNP (R=0.61, PCLT (the top quartile,≥109min). In AF patients prothrombotic fibrin clot properties assessed ex vivo are determined by PAI-1 and NT-proBNP and this phenotype is associated with prior ischemic stroke. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Studies on coagulation, fibrinolysis, kallikrein-kinin and complement activation in systemic and pulmonary circulation during hip arthroplasty with acrylic cement.

    Science.gov (United States)

    Dahl, O E; Molnar, I; Vinje, A; Rø, J S; Kierulf, P; Andersen, A B; Dalaker, K; Prydz, H

    1988-06-15

    This study was designed to evaluate the contribution of the plasma cascade systems to the cardiopulmonary complications, occasionally leading to sudden death during hip arthroplasty using acrylic cement. The intraoperative pattern following uneventful surgery was therefore investigated in 8 patients with osteoarthrosis with frequent sampling from the radial and pulmonary arteries. The following general findings emerged: A gradual consumption of coagulation factors (platelets, fibrinogen, factor VII, antithrombin III), fibrinolytic components (plasminogen, alpha-2-antiplasmin), kallikrein-kinin factors (prekallikrein, kallikrein inhibitor) and complement factors (C3c, C4) was observed. Some intrapulmonary proteolytic inhibition was noticed as evidenced by lower arterial than mixed venous blood levels of alpha-2-antiplasmin and kallikrein inhibitor. Insignificant changes occurred for factor VII-phospholipid complex. A rapid, massive and transient increase in fibrinopeptide A (FPA) values in the radial artery, as opposed to the moderate increase in the pulmonary artery, was found immediately after reaming and broaching of bone. This probably reflected intrapulmonary fibrinogen to fibrin conversion, reaching a maximum 15-20 minutes before the femoral implantation. As estimated from the FPA arterial peak values and the fall in fibrinogen concentrations, approximately 5-10% of the circulating fibrinogen molecules were devoided of FPA during this intraoperative phase. The marked a-v difference in FPA level supports earlier findings of intrapulmonary fibrin formation and deposition. This process, however preceded the critical period of cardiorespiratory collapse (CRC) by at least 15 minutes, and may thus predispose to this complication.

  2. Acid corrosion inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Chen, N G

    1964-04-28

    An acid corrosion inhibitor is prepared by a 2-stage vacuum evaporation of effluents obtained from the ammonia columns of the coking oven plant. The effluent, leaving a scrubber in which the phenols are removed at a temperature of 98$C, passes through a quartz filter and flows into a heated chamber in which it is used for preheating a solution circulating through a vacuum unit, maintaining the temperature of the solution at 55$ to 60$C. The effluent enters a large tank in which it is boiled at 55$ to 60$C under 635 to 640 mm Hg pressure. Double evaporation of this solution yields a very effective acid corrosion inhibitor. Its corrosion-preventing effect is 97.9% compared with 90.1% for thiourea and 88.5% for urotropin under identical conditions.

  3. Benzoylurea Chitin Synthesis Inhibitors.

    Science.gov (United States)

    Sun, Ranfeng; Liu, Chunjuan; Zhang, Hao; Wang, Qingmin

    2015-08-12

    Benzoylurea chitin synthesis inhibitors are widely used in integrated pest management (IPM) and insecticide resistance management (IRM) programs due to their low toxicity to mammals and predatory insects. In the past decades, a large number of benzoylurea derivatives have been synthesized, and 15 benzoylurea chitin synthesis inhibitors have been commercialized. This review focuses on the history of commercial benzolyphenylureas (BPUs), synthetic methods, structure-activity relationships (SAR), action mechanism research, environmental behaviors, and ecotoxicology. Furthermore, their disadvantages of high risk to aquatic invertebrates and crustaceans are pointed out. Finally, we propose that the para-substituents at anilide of benzoylphenylureas should be the functional groups, and bipartite model BPU analogues are discussed in an attempt to provide new insight for future development of BPUs.

  4. A study of the effect of ethamsylate (Dicynene) on the bleeding time, von Willebrand factor level and fibrinolysis in patients with von Willebrand's disease.

    Science.gov (United States)

    Hutton, R A; Hales, M; Kernoff, P B

    1988-12-22

    Nine patients with clinically moderate or severe Type I von Willebrand's disease were treated for 2 weeks with ethamsylate (2 g/day in four equal doses) and with a matched placebo in a randomised double-blind trial. Template bleeding time, von Willebrand factor activity (ristocetin co-factor) and antigen, euglobulin lysis time and type I tissue plasminogen activator inhibitor were determined before and at the end of each treatment period. None of these parameters showed any significant change attributable to ethamsylate. Thus, despite the fact that five patients thought subjectively that their bleeding symptoms improved during ethamsylate treatment compared to only one while on placebo, we obtained no evidence that the drug was of benefit to patients with von Willebrand's disease.

  5. Clinical evaluation of a new synthetic protease inhibitor in open heart surgery. Effect on plasma serotonin and histamine release and blood conservation.

    Science.gov (United States)

    Miyamoto, Y; Nakano, S; Kaneko, M; Takano, H; Matsuda, H

    1992-01-01

    To achieve more physiologically successful cardiopulmonary bypass (CPB), the effects of a new synthetic protease inhibitor, nafamostat mesilate (FUT), were examined in open heart surgery. Thirty adult patients were divided into two groups. In Group F (GpF; n = 15), 2 mg/kg/hr of FUT was administered continuously during CPB and 0.2 mg/kg/hr before and after CPB. FUT was not given to Group C patients (GpC; n = 15), who acted as controls. Serotonin and histamine levels in plasma, platelet counts, platelet adhesive function levels, and alpha 2 plasmin inhibitor-plasmin complexes (PIC) were serially measured. The serotonin level in GpF was significantly lower at 5 min of CPB than in GpC. Histamine levels in GpC decreased remarkably after starting CPB, then later recovered; by contrast, they did not decrease in GpF during CPB. At 1 hr after CPB, platelet counts were higher (p platelet adhesion was lower (p platelets and inhibiting fibrinolysis during CPB.

  6. DGAT inhibitors for obesity.

    Science.gov (United States)

    Matsuda, Daisuke; Tomoda, Hiroshi

    2007-10-01

    Obesity is characterized by the accumulation of triacylglycerol in adipocytes. Diacylglycerol acyltransferase (DGAT) catalyzes the final reaction of triacylgycerol synthesis. Two isozymes of DGAT, DGAT1 and DGAT2, have been reported. Increased DGAT2 activity has a role in steatosis, while DGAT1 plays a role in very (V)LDL synthesis; increased plasma VLDL concentrations may promote obesity and thus DGAT1 is considered a potential therapeutic target of inhibition for obesity control. Several DGAT inhibitors of natural and synthetic origin have been reported, and their future prospect as anti-obesity drugs is discussed in this review.

  7. Basic Evaluation of the Newly Developed "Lias Auto P-FDP" Assay and the Influence of Plasmin-α2 Plasmin Inhibitor Complex Values on Discrepancy in the Comparison with "Lias Auto D-Dimer Neo" Assay.

    Science.gov (United States)

    Kumano, Osamu; Ieko, Masahiro; Komiyama, Yutaka; Naito, Sumiyoshi; Yoshida, Mika; Takahashi, Nobuhiko; Ohmura, Kazumasa; Hayasaki, Junki; Hayakawa, Mineji

    2018-04-01

    Laboratory determination of fibrin/fibrinogen degradation products (FDP) levels, along with that of the D-dimer, is important for assessing the fibrinolytic situation. Recently, we developed a new FDP reagent "Lias Auto P-FDP", which can detect various FDP fragments. The purpose of this study was to evaluate the basic performance of the newly developed Lias Auto P-FDP and compare it with Lias Auto D-Dimer Neo assay. The within-run precision of Lias Auto P-FDP and Lias Auto D-Dimer was determined 20 times in low and high value controls. The between-day precision was evaluated five times a day for five days. The linearity study was performed by diluting high value samples for 2 - 10-fold and 2 - 8-fold. The comparative study was performed using 172 patient samples with elevated FDP values. For the discrepancy analysis, the samples were divided into three groups by the discrepancy percentage between the FDP and D-dimer values. The groups were defined as follows: lower discrepancy group, less than -20%; no discrepancy group, -20% to 20%; upper discrepancy group, more than 20%. The coefficient of variation % (CV%) in within-run and between-day precision were within 3.8% for both FDP and the D-dimer. The correlation coefficients were more than 0.999 and the linearity was high. In the comparative study, the values of FDP were higher than that of the D-dimer in all samples. The median FDP and D-dimer values of lower discrepancy, no discrepancy, and upper discrepancy groups were 11.8, 20.3, and 51.4, and 8.0, 11.3, and 13.1, respectively. FDP showed an increasing tendency but D-Dimer showed constant values. Thus, the possible cause of discrepancy between FDP and D-dimer values were the elevated FDP values. In addition, the values of plasmin-α2 plasmin inhibitor complex (PIC) in the upper discrepancy group were higher than that of the lower and no discrepancy groups, indicating progression of fibrinolysis. In this study, we evaluated the newly developed Lias Auto P

  8. Pulmonary Toxicity of Cholinesterase Inhibitors

    National Research Council Canada - National Science Library

    Hilmas, Corey; Adler, Michael; Baskin, Steven I; Gupta, Ramesh C

    2006-01-01

    .... Whereas nerve agents were produced primarily for military deployment, other cholinesterase inhibitors were used for treating conditions such as myasthenia gravis and as pretreaunents for nerve agent exposure...

  9. Plasminogen activator inhibitor-1 is elevated in patients with COPD independent of metabolic and cardiovascular function

    Directory of Open Access Journals (Sweden)

    Waschki B

    2017-03-01

    Full Text Available Benjamin Waschki,1–3 Henrik Watz,2,3 Olaf Holz,4,5 Helgo Magnussen,2,3 Beata Olejnicka,6 Tobias Welte,5,7 Klaus F Rabe,1,3 Sabina Janciauskiene5,7 1Pneumology, LungenClinic Grosshansdorf, Grosshansdorf, Germany; 2Pulmonary Research Institute at LungenClinic Grosshansdorf, Grosshansdorf, Germany; 3Airway Research Center North (ARCN, German Center for Lung Research (DZL, Grosshansdorf, Germany; 4Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany; 5Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH, German Center for Lung Research (DZL, Hannover, Germany; 6Department of Medicine, Trelleborg Hospital, Trelleborg, Sweden; 7Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany Introduction: Plasminogen activator inhibitor-1 (PAI-1, a major inhibitor of fibrinolysis, is associated with thrombosis, obesity, insulin resistance, dyslipidemia, and premature aging, which all are coexisting conditions of chronic obstructive pulmonary disease (COPD. The role of PAI-1 in COPD with respect to metabolic and cardiovascular functions is unclear. Methods: In this study, which was nested within a prospective cohort study, the serum levels of PAI-1 were cross-sectionally measured in 74 stable COPD patients (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Stages I–IV and 18 controls without lung disease. In addition, triglycerides, high-density lipoprotein cholesterol, fasting plasma glucose, waist circumference, blood pressure, smoking status, high-sensitive C-reactive protein (hs-CRP, adiponectin, ankle–brachial index, N-terminal pro-B-type natriuretic peptide, and history of comorbidities were also determined. Results: The serum levels of PAI-1 were significantly higher in COPD patients than in controls, independent of a broad spectrum of possible confounders including metabolic and cardiovascular dysfunction. A multivariate regression analysis revealed

  10. Biological abatement of cellulase inhibitors

    Science.gov (United States)

    Bio-abatement uses a fungus to metabolize and remove fermentation inhibitors. To determine whether bio-abatement could alleviate enzyme inhibitor effects observed in biomass liquors after pretreatment, corn stover at 10% (w/v) solids was pretreated with either dilute acid or liquid hot water. The ...

  11. Proteinaceous alpha-araylase inhibitors

    DEFF Research Database (Denmark)

    Svensson, Birte; Fukuda, Kenji; Nielsen, P.K.

    2004-01-01

    -amylase inhibitors belong to seven different protein structural families, most of which also contain evolutionary related proteins without inhibitory activity. Two families include bifunctional inhibitors acting both on alpha-amylases and proteases. High-resolution structures are available of target alpha...

  12. Corrosion inhibitors. Manufacture and technology

    International Nuclear Information System (INIS)

    Ranney, M.W.

    1976-01-01

    Detailed information is presented relating to corrosion inhibitors. Areas covered include: cooling water, boilers and water supply plants; oil well and refinery operations; fuel and lubricant additives for automotive use; hydraulic fluids and machine tool lubes; grease compositions; metal surface treatments and coatings; and general processes for corrosion inhibitors

  13. [ACE inhibitors and the kidney].

    Science.gov (United States)

    Hörl, W H

    1996-01-01

    Treatment with ACE inhibitors results in kidney protection due to reduction of systemic blood pressure, intraglomerular pressure, an antiproliferative effect, reduction of proteinuria and a lipid-lowering effect in proteinuric patients (secondary due to reduction of protein excretion). Elderly patients with diabetes melitus, coronary heart disease or peripheral vascular occlusion are at risk for deterioration of kidney function due to a high frequency of renal artery stenosis in these patients. In patients with renal insufficiency dose reduction of ACE inhibitors is necessary (exception: fosinopril) but more important is the risk for development of hyperkalemia. Patients at risk for renal artery stenosis and patients pretreated with diuretics should receive a low ACE inhibitor dosage initially ("start low - go slow"). For compliance reasons once daily ACE inhibitor dosage is recommended.

  14. [Inventive activity of the Departments of Chemistry and Biochemistry of Enzymes, and Protein Structure and Function of the Palladin Institute of Biochemistry of NAS of Ukraine. Part III. Diagnostic test-systems for analysis of fibrinolysis blood system and novel approaches to thrombosis treatment].

    Science.gov (United States)

    Danilova, V M; Vynogradova, R P; Chernysh, I Yu

    2016-01-01

    This article continues analysis of scientific achievements of the Institute of Biochemistry in the study of hemostasis system. Two previous articles were focused on the studies of blood coagulation proteins and development of the immune-enzyme test-systems for evaluation of the risk of thrombosis upon various pathologies. This article highlights the research on the blood fibrinolysis system and new approaches to thrombosis treatment, which were developed (and are under development) in the Palladin Institute of Biochemistry of the NAS of Ukraine, in particular, in the Department of Chemistry and Biochemistry of Enzymes headed previously by Dr.Sci.(Biol.) S. O. Kudinov and now by Dr.Sci.(Biol.) T .V. Grinenko, and also in the Department of Protein Structure and Function headed by Dr.Biol.Sci. E. M. Makogonenko. The fundamental knowledge of protein molecule functions and mechanisms of regulation of blood coagulation and fibrinolysis opens up new opportunities to diagnose hemostasis disorders and control the effectiveness of the cardiovascular disease treatment and also contributes to development of new techniques for isolation of new proteins – promising therapeutic agents.

  15. The Association of Plasminogen Activator Inhibitor Type 1 (PAI-1) Level and PAI-1 4G/5G Gene Polymorphism with the Formation and the Grade of Endometrial Cancer.

    Science.gov (United States)

    Yıldırım, Malik Ejder; Karakuş, Savas; Kurtulgan, Hande Küçük; Kılıçgün, Hasan; Erşan, Serpil; Bakır, Sevtap

    2017-08-01

    Plasminogen activator inhibitor type 1 (PAI-1) is a serine protease inhibitor (Serpine 1), and it inhibits both tissue plasminogen activator and urokinase plasminogen activator which are important in fibrinolysis. We aimed to find whether there is a possible association between PAI-1 level, PAI-1 4G/5G polymorphism, and endometrial cancer. PAI-1 levels in peripheral blood were determined in 82 patients with endometrial carcinoma and 76 female healthy controls using an enzyme-linked immunoassay (ELISA). Then, the genomic DNA was extracted and screened by reverse hybridization procedure (Strip assay) to detect PAI 1 4G/5G polymorphism. The levels of PAI-1 in the patients were higher statistically in comparison to controls (P 5G polymorphism was quite different between patients and controls (P = 0.008), and 4G allelic frequency was significantly higher in the patients of endometrial cancer than in controls (P = 0.026). We found significant difference between Grade 1 and Grade 2+3 patients in terms of the PAI-1 levels (P = 0.047). There was no association between PAI-1 4G/5G polymorphism and the grades of endometrial cancer (P = 0.993). Our data suggest that the level of PAI-1 and PAI-1 4G/5G gene polymorphism are effective in the formation of endometrial cancer. PAI-1 levels are also associated with the grades of endometrial cancer.

  16. Metal corrosion inhibitors and ecology

    International Nuclear Information System (INIS)

    Krasts, H.; Svarce, J.; Berge, B.

    1999-01-01

    The use of metal corrosion inhibitors in water is one of the cheapest method to protect metals against corrosion. However, the used inhibitors can come to surface water in the course of time and can become as source of environmental pollution. It is important to co-ordinate amount of substances in the elaborated inhibitors not only with demands for metal protection, but also with demands for quality of surface water and drinking water according to normative statements: 3.5 mg/l (as PO 4 ) for hexametaphosphate, tripolyphosphate and phosphonate; 40 mg/l (as SiO 2 for silicate, up to 1 mg/l for CU 2+ ; up to 5 mg/l for Zn 2+ ; up to 1 mg/l for B; up to 0.5 mg/l for Mo 2+ . The examples of the elaborated inhibitors are given. Many organic substances can be used as corrosion inhibitors, but there is shortage of standard methods for their analysis in water in Latvia. Removing of salt's deposits from boilers needs elaboration of a separate normative statement for dispersing waste water which content chloride at high concentration and heavy metals. (authors)

  17. Positron emitter labeled enzyme inhibitors

    International Nuclear Information System (INIS)

    Fowler, J.S.; MacGregor, R.R.; Wolf, A.P.; Langstrom, B.

    1990-01-01

    This invention involves a new strategy for imagining and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide inactivators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography

  18. ROCK inhibitors in ocular disease

    Directory of Open Access Journals (Sweden)

    Eva Halasz

    2016-12-01

    Full Text Available Rho kinases (ROCKs have a crucial role in actin-cytoskeletal reorganization and thus are involved in broad aspects of cell motility, from smooth muscle contraction to neurite outgrowth. The first marketed ROCK inhibitor, called fasudil, has been used safely for treatment of cerebral vasospasm since 1995 in Japan. During the succeeding decades ROCK inhibitors have been applied in many pathological conditions from central nervous system disorders to cardiovascular disease as potential therapeutic agents or experimental tools to help understand the underlying (pathomechanisms. In 2014, a fasudil derivate named ripasudil was accepted for clinical use in glaucoma and ocular hypertension. Since ROCK kinases are widely expressed in ocular tissues, they have been implicated in the pathology of many ocular conditions such as corneal dysfunction, glaucoma, cataract, diabetic retinopathy, age-related macular degeneration, and retinal detachment. This paper aims to provide an overview of the most recent status/application of ROCK inhibitors in the field of eye disease.

  19. Endometrial haemostasis and menstruation.

    Science.gov (United States)

    Davies, Joanna; Kadir, Rezan A

    2012-12-01

    Under normal physiological circumstances menstruation is a highly regulated, complex process that is under strict hormonal control. During normal menstruation, progesterone withdrawal initiates menstruation. The cessation of menstrual bleeding is achieved by endometrial haemostasis via platelet aggregation, fibrin deposition and thrombus formation. Local endocrine, immunological and haemostatic factors interact at a molecular level to control endometrial haemostasis. Tissue factor and thrombin play a key role locally in the cessation of menstrual bleeding through instigation of the coagulation factors. On the other hand, fibrinolysis prevents clot organisation within the uterine cavity while plasminogen activator inhibitors (PAI) and thrombin-activatable fibrinolysis inhibitors control plasminogen activators and plasmin activity. Abnormalities of uterine bleeding can result from imbalance of the haemostatic factors. The most common abnormality of uterine bleeding is heavy menstrual bleeding (HMB). Modern research has shown that an undiagnosed bleeding disorder, in particular von Willebrand disease (VWD) and platelet function disorders, can be an underlying cause of HMB. This has led to a change in the approach to the management of HMB. While full haemostatic assessment is not required for all women presenting with HMB, menstrual score and bleeding score can help to discriminate women who are more likely to have a bleeding disorder and benefit from laboratory haemostatic evaluation. Haemostatic agents (tranexamic acid and DDAVP) enhance systemic and endometrial haemostasis and are effective in reducing menstrual blood loss in women with or without bleeding disorders. Further research is required to enhance our understanding of the complex interactions of haemostatic factors in general, and specifically within the endometrium. This will lead to the development of more targeted interventions for the management of abnormal uterine bleeding in the future.

  20. Histones Differentially Modulate the Anticoagulant and Profibrinolytic Activities of Heparin, Heparin Derivatives, and Dabigatran.

    Science.gov (United States)

    Ammollo, Concetta Tiziana; Semeraro, Nicola; Carratù, Maria Rosaria; Colucci, Mario; Semeraro, Fabrizio

    2016-02-01

    The antithrombin activity of unfractionated heparin (UFH) is offset by extracellular histones, which, along with DNA, represent a novel mediator of thrombosis and a structural component of thrombi. Here, we systematically evaluated the effect of histones, DNA, and histone-DNA complexes on the anticoagulant and profibrinolytic activities of UFH, its derivatives enoxaparin and fondaparinux, and the direct thrombin inhibitor dabigatran. Thrombin generation was assessed by calibrated automated thrombinography, inhibition of factor Xa and thrombin by synthetic substrates, tissue plasminogen activator-mediated clot lysis by turbidimetry, and thrombin-activatable fibrinolysis inhibitor (TAFI) activation by a functional assay. Histones alone delayed coagulation and slightly stimulated fibrinolysis. The anticoagulant activity of UFH and enoxaparin was markedly inhibited by histones, whereas that of fondaparinux was enhanced. Histones neutralized both the anti-Xa and anti-IIa activities of UFH and preferentially blocked the anti-IIa activity of enoxaparin. The anti-Xa activity of fondaparinux was not influenced by histones when analyzed by chromogenic substrates, but was potentiated in a plasma prothrombinase assay. Histones inhibited the profibrinolytic activity of UFH and enoxaparin and enhanced that of fondaparinux by acting on the modulation of TAFI activation by anticoagulants. Histone H1 was mainly responsible for these effects. Histone-DNA complexes, as well as intact neutrophil extracellular traps, impaired the activities of UFH, enoxaparin, and fondaparinux. Dabigatran was not noticeably affected by histones and/or DNA, whatever the assay performed. In conclusion, histones and DNA present in the forming clot may variably influence the antithrombotic activities of anticoagulants, suggesting a potential therapeutic advantage of dabigatran and fondaparinux over heparins. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  1. Prosthetic valve obstruction: Redo surgery or fibrinolysis?

    Directory of Open Access Journals (Sweden)

    Avinash Inamdar

    2017-01-01

    Full Text Available Objective: The aim of this study was to compare the efficacy and safety of surgery versus fibrinolytic therapy in patients with prosthetic valve obstruction. Materials and Methods: We compared 15 patients of prosthetic valve thrombosis treated by surgical line of management and another 15 patients treated by thrombolysis. All patients were initially assessed by clinical evaluation and diagnosis confirmed by transthoracic and transesophageal two-dimensional echocardiography. Depending on hemodynamic stability, pannus, or thrombus on transesophageal echocardiography, the patients were assigned surgical or medical line of management. Results: Patients mortality rate was 40% in fibrinolytic group and 13.33% in surgical group. Recurrence was 40% in fibrinolytic group while there was no recurrence till date in surgery group. Complications were more in fibrinolytic group as opposed to surgery group patient. Conclusion: From our experience, we conclude that redo surgery is effective and definitive treatment, especially in patients with stable hemodynamic conditions.

  2. Azidoblebbistatin, a photoreactive myosin inhibitor

    Science.gov (United States)

    Képiró, Miklós; Várkuti, Boglárka H.; Bodor, Andrea; Hegyi, György; Drahos, László; Kovács, Mihály; Málnási-Csizmadia, András

    2012-01-01

    Photoreactive compounds are important tools in life sciences that allow precisely timed covalent crosslinking of ligands and targets. Using a unique technique we have synthesized azidoblebbistatin, which is a derivative of blebbistatin, the most widely used myosin inhibitor. Without UV irradiation azidoblebbistatin exhibits identical inhibitory properties to those of blebbistatin. Using UV irradiation, azidoblebbistatin can be covalently crosslinked to myosin, which greatly enhances its in vitro and in vivo effectiveness. Photo-crosslinking also eliminates limitations associated with the relatively low myosin affinity and water solubility of blebbistatin. The wavelength used for photo-crosslinking is not toxic for cells and tissues, which confers a great advantage in in vivo tests. Because the crosslink results in an irreversible association of the inhibitor to myosin and the irradiation eliminates the residual activity of unbound inhibitor molecules, azidoblebbistatin has a great potential to become a highly effective tool in both structural studies of actomyosin contractility and the investigation of cellular and physiological functions of myosin II. We used azidoblebbistatin to identify previously unknown low-affinity targets of the inhibitor (EC50 ≥ 50 μM) in Dictyostelium discoideum, while the strongest interactant was found to be myosin II (EC50 = 5 μM). Our results demonstrate that azidoblebbistatin, and potentially other azidated drugs, can become highly useful tools for the identification of strong- and weak-binding cellular targets and the determination of the apparent binding affinities in in vivo conditions. PMID:22647605

  3. Biological abatement of cellulase inhibitors.

    Science.gov (United States)

    Cao, Guangli; Ximenes, Eduardo; Nichols, Nancy N; Zhang, Leyu; Ladisch, Michael

    2013-10-01

    Removal of enzyme inhibitors released during lignocellulose pretreatment is essential for economically feasible biofuel production. We tested bio-abatement to mitigate enzyme inhibitor effects observed in corn stover liquors after pretreatment with either dilute acid or liquid hot water at 10% (w/v) solids. Bio-abatement of liquors was followed by enzymatic hydrolysis of cellulose. To distinguish between inhibitor effects on enzymes and recalcitrance of the substrate, pretreated corn stover solids were removed and replaced with 1% (w/v) Solka Floc. Cellulose conversion in the presence of bio-abated liquors from dilute acid pretreatment was 8.6% (0.1x enzyme) and 16% (1x enzyme) higher than control (non-abated) samples. In the presence of bio-abated liquor from liquid hot water pretreated corn stover, 10% (0.1x enzyme) and 13% (1x enzyme) higher cellulose conversion was obtained compared to control. Bio-abatement yielded improved enzyme hydrolysis in the same range as that obtained using a chemical (overliming) method for mitigating inhibitors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Phosphodiesterase inhibitors in clinical urology.

    Science.gov (United States)

    Ückert, Stefan; Kuczyk, Markus A; Oelke, Matthias

    2013-05-01

    To date, benign diseases of the male and female lower urinary and genital tract, such as erectile dysfunction, bladder overactivity, lower urinary tract symptomatology secondary to benign prostatic hyperplasia and symptoms of female sexual dysfunction (including arousal and orgasmic disorders), can be therapeutically approached by influencing the function of the smooth musculature of the respective tissues. The use of isoenzyme-selective phosphodiesterase (PDE) inhibitors is considered a great opportunity to treat various diseases of the human urogenital tract. PDE inhibitors, in particular the PDE5 (cyclic GMP PDE) inhibitors avanafil, lodenafil, sildenafil, tadalafil, udenafil and vardenafil, are regarded as efficacious, having a fast onset of drug action and an improved effect-to-adverse event ratio, combining a high response rate with the advantage of an on-demand intake. The purpose of this review is to summarize recent as well as potential future indications, namely, erectile dysfunction, Peyronie's disease, overactive bladder, urinary stone disease, lower urinary tract symptomatology secondary to benign prostatic hyperplasia and premature ejaculation, for the use of PDE inhibitors in clinical urology.

  5. Inhibitors of mTOR

    NARCIS (Netherlands)

    Klümpen, Heinz-Josef; Beijnen, Jos H.; Gurney, Howard; Schellens, Jan H. M.

    2010-01-01

    Inhibitors of mammalian target of rapamycin (mTOR) have been approved for the treatment of renal cell carcinoma and appear to have a role in the treatment of other malignancies. The primary objective of this drug review is to provide pharmacokinetic and dynamic properties of the commonly used drugs

  6. Retroviral proteinases and their inhibitors

    Czech Academy of Sciences Publication Activity Database

    Sedláček, Juraj

    2000-01-01

    Roč. 3, 3,4 (2000), s. 23-24 [ Proteolytic enzymes and their inhibitors in physiology and pathogenesis. 14.09.2000, Plzen] Institutional research plan: CEZ:AV0Z5052915 Subject RIV: EB - Genetics ; Molecular Biology

  7. Monoamine depletion by reuptake inhibitors

    Directory of Open Access Journals (Sweden)

    Hinz M

    2011-10-01

    Full Text Available Marty Hinz1, Alvin Stein2, Thomas Uncini31Clinical Research, NeuroResearch Clinics Inc, Cape Coral, FL; 2Stein Orthopedic Associates, Plantation, FL; 3DBS Labs Inc, Duluth, MN, USABackground: Disagreement exists regarding the etiology of cessation of the observed clinical results with administration of reuptake inhibitors. Traditionally, when drug effects wane, it is known as tachyphylaxis. With reuptake inhibitors, the placebo effect is significantly greater than the drug effect in the treatment of depression and attention deficit hyperactivity disorder, leading some to assert that waning of drug effects is placebo relapse, not tachyphylaxis.Methods: Two groups were retrospectively evaluated. Group 1 was composed of subjects with depression and Group 2 was composed of bariatric subjects treated with reuptake inhibitors for appetite suppression.Results: In Group 1, 200 subjects with depression were treated with citalopram 20 mg per day. A total of 46.5% (n = 93 achieved relief of symptoms (Hamilton-D rating score ≤ 7, of whom 37 (39.8% of whom experienced recurrence of depression symptoms, at which point an amino acid precursor formula was started. Within 1–5 days, 97.3% (n = 36 experienced relief of depression symptoms. In Group 2, 220 subjects were treated with phentermine 30 mg in the morning and citalopram 20 mg at 4 pm. In this group, 90.0% (n = 198 achieved adequate appetite suppression. The appetite suppression ceased in all 198 subjects within 4–48 days. Administration of an amino acid precursor formula restored appetite suppression in 98.5% (n = 195 of subjects within 1–5 days.Conclusion: Reuptake inhibitors do not increase the total number of monoamine molecules in the central nervous system. Their mechanism of action facilitates redistribution of monoamines from one place to another. In the process, conditions are induced that facilitate depletion of monoamines. The "reuptake inhibitor monoamine depletion theory" of this paper

  8. Evaluating Factor XIII Specificity for Glutamine-Containing Substrates Using a MALDI-TOF Mass Spectrometry Assay

    Science.gov (United States)

    Doiphode, Prakash G.; Malovichko, Marina V.; Mouapi, Kelly Njine; Maurer, Muriel C.

    2014-01-01

    Activated Factor XIII (FXIIIa) catalyzes the formation of γ-glutamyl-ε-lysyl cross-links within the fibrin blood clot network. Although several cross-linking targets have been identified, the characteristic features that define FXIIIa substrate specificity are not well understood. To learn more about how FXIIIa selects its targets, a matrix-assisted laser desorption ionization – time of flight mass spectrometry (MALDI-TOF MS) based assay was developed that could directly follow the consumption of a glutamine-containing substrate and the formation of a cross-linked product with glycine ethylester. This FXIIIa kinetics assay is no longer reliant on a secondary coupled reaction, on substrate labeling, or on detecting the final deacylation portion of the transglutaminase reaction. With the MALDI-TOF MS assay, glutamine-containing peptides derived from α2-antiplasmin, S. Aureus fibronectin binding protein A, and thrombin activatable fibrinolysis inhibitor were examined directly. Results suggest that the FXIIIa active site surface responds to changes in substrate residues following the reactive glutamine. The P-1 substrate position is sensitive to charge character and the P-2 and P-3 to the broad FXIIIa substrate specificity pockets. The more distant P-8 to P-11 region serves as a secondary substrate anchoring point. New knowledge on FXIIIa specificity may be used to design better substrates or inhibitors of this transglutaminase. PMID:24751466

  9. Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

    Science.gov (United States)

    Serotonin and norepinephrine reuptake inhibitors (SNRIs) Antidepressant SNRIs help relieve depression symptoms, such as irritability and sadness, ... effects they may cause. By Mayo Clinic Staff Serotonin and norepinephrine reuptake inhibitors (SNRIs) are a class ...

  10. Contemporary protease inhibitors and cardiovascular risk

    DEFF Research Database (Denmark)

    Lundgren, Jens; Mocroft, Amanda; Ryom, Lene

    2018-01-01

    PURPOSE OF REVIEW: To review the evidence linking use of HIV protease inhibitors with excess risk of cardiovascular disease (CVD) in HIV+ populations. RECENT FINDINGS: For the two contemporary most frequently used protease inhibitors, darunavir and atazanavir [both pharmacologically boosted...

  11. Reduction rules for reset/inhibitor nets

    NARCIS (Netherlands)

    Verbeek, H.M.W.; Wynn, M.T.; Aalst, van der W.M.P.; Hofstede, ter A.H.M.

    2010-01-01

    Reset/inhibitor nets are Petri nets extended with reset arcs and inhibitor arcs. These extensions can be used to model cancellation and blocking. A reset arc allows a transition to remove all tokens from a certain place when the transition fires. An inhibitor arc can stop a transition from being

  12. Allosteric small-molecule kinase inhibitors

    DEFF Research Database (Denmark)

    Wu, Peng; Clausen, Mads Hartvig; Nielsen, Thomas E.

    2015-01-01

    current barriers of kinase inhibitors, including poor selectivity and emergence of drug resistance. In spite of the small number of identified allosteric inhibitors in comparison with that of inhibitors targeting the ATP pocket, encouraging results, such as the FDA-approval of the first small...

  13. Plasma fibrin clot properties in the G20210A prothrombin mutation carriers following venous thromboembolism: the effect of rivaroxaban.

    Science.gov (United States)

    Janion-Sadowska, Agnieszka; Natorska, Joanna; Siudut, Jakub; Ząbczyk, Michal; Stanisz, Andrzej; Undas, Anetta

    2017-08-30

    We sought to investigate whether the G20210A prothrombin mutation modifies plasma fibrin clot properties in patients after venous thromboembolism (VTE) and how rivaroxaban treatment affects these alterations. We studied 34 prothrombin mutation heterozygous carriers and sex- and age-matched 34 non-carriers, all at least three months since the first VTE episode, before and during treatment with rivaroxaban. Clot permeability (K s ) and clot lysis time (CLT) with or without elimination of thrombin activatable fibrinolysis inhibitor (TAFI) were assessed at baseline, 2-6 hours (h) after and 20-25 h after intake of rivaroxaban (20 mg/day). At baseline, the prothrombin mutation group formed denser clots (K s -12 %, p=0.0006) and had impaired fibrinolysis (CLT +14 %, p=0.004, and CLT-TAFI +13 %, p=0.03) compared with the no mutation group and were similar to those observed in 15 healthy unrelated prothrombin mutation carriers. The G20210A prothrombin mutation was the independent predictor for K s and CLT before rivaroxaban intake. At 2-6 h after rivaroxaban intake, clot properties improved in both G20210A carriers and non-carriers (K s +38 %, and +37 %, CLT -25 % and -25 %, CLT-TAFI -20 % and -24 %, respectively, all pCLT +17 %, CLT-TAFI +13 %, all p<0.001). Rivaroxaban concentration correlated with fibrin clot properties. After 20-25 h since rivaroxaban intake most clot properties returned to baseline. Rivaroxaban-related differences in clot structure were confirmed by scanning electron microscopy images. In conclusion, rivaroxaban treatment, though improves fibrin clot properties, cannot abolish more prothrombotic fibrin clot phenotype observed in prothrombin mutation carriers following VTE.

  14. Lack of TAFI increases brain damage and microparticle generation after thrombolytic therapy in ischemic stroke.

    Science.gov (United States)

    Orbe, J; Alexandru, N; Roncal, C; Belzunce, M; Bibiot, P; Rodriguez, J A; Meijers, J C M; Georgescu, A; Paramo, J A

    2015-08-01

    Thrombin-activatable fibrinolysis inhibitor (TAFI) plays an important role in coagulation and fibrinolysis. Whereas TAFI deficiency may lead to a haemorrhagic tendency, data from TAFI knockout mice (TAFI-/-) are controversial and no differences have been reported in these animals after ischemic stroke. There are also no data regarding the role of circulating microparticles (MPs) in TAFI-/-. to examine the effect of tPA on the rate of intracranial haemorrhage (ICH) and on MPs generated in a model of ischemic stroke in TAFI-/- mice. Thrombin was injected into the middle cerebral artery (MCA) to analyse the effect of tPA (10mg/Kg) on the infarct size and haemorrhage in the absence of TAFI. Immunofluorescence for Fluoro-Jade C was performed on frozen brain slides to analyse neuronal degeneration after ischemia. MPs were isolated from mouse blood and their concentrations calculated by flow cytometry. Compared with saline, tPA significantly increased the infarct size in TAFI-/- mice (p<0.05). Although plasma fibrinolytic activity (fibrin plate assay) was higher in these animals, no macroscopic or microscopic ICH was detected. A positive signal for apoptosis and degenerating neurons was observed in the infarct area, being significantly higher in tPA treated TAFI-/- mice (p<0.05). Interestingly, higher numbers of MPs were found in TAFI-/- plasma as compared to wild type, after stroke (p<0.05). TAFI deficiency results in increased brain damage in a model of thrombolysis after ischemic stroke, which was not associated with bleeding but with neuronal degeneration and MP production. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Histone deacetylase inhibitors (HDACIs): multitargeted anticancer agents.

    Science.gov (United States)

    Ververis, Katherine; Hiong, Alison; Karagiannis, Tom C; Licciardi, Paul V

    2013-01-01

    Histone deacetylase (HDAC) inhibitors are an emerging class of therapeutics with potential as anticancer drugs. The rationale for developing HDAC inhibitors (and other chromatin-modifying agents) as anticancer therapies arose from the understanding that in addition to genetic mutations, epigenetic changes such as dysregulation of HDAC enzymes can alter phenotype and gene expression, disturb homeostasis, and contribute to neoplastic growth. The family of HDAC inhibitors is large and diverse. It includes a range of naturally occurring and synthetic compounds that differ in terms of structure, function, and specificity. HDAC inhibitors have multiple cell type-specific effects in vitro and in vivo, such as growth arrest, cell differentiation, and apoptosis in malignant cells. HDAC inhibitors have the potential to be used as monotherapies or in combination with other anticancer therapies. Currently, there are two HDAC inhibitors that have received approval from the US FDA for the treatment of cutaneous T-cell lymphoma: vorinostat (suberoylanilide hydroxamic acid, Zolinza) and depsipeptide (romidepsin, Istodax). More recently, depsipeptide has also gained FDA approval for the treatment of peripheral T-cell lymphoma. Many more clinical trials assessing the effects of various HDAC inhibitors on hematological and solid malignancies are currently being conducted. Despite the proven anticancer effects of particular HDAC inhibitors against certain cancers, many aspects of HDAC enzymes and HDAC inhibitors are still not fully understood. Increasing our understanding of the effects of HDAC inhibitors, their targets and mechanisms of action will be critical for the advancement of these drugs, especially to facilitate the rational design of HDAC inhibitors that are effective as antineoplastic agents. This review will discuss the use of HDAC inhibitors as multitargeted therapies for malignancy. Further, we outline the pharmacology and mechanisms of action of HDAC inhibitors while

  16. Calcineurin-inhibitor pain syndrome.

    Science.gov (United States)

    Prommer, Eric

    2012-07-01

    There has been increased recognition of calcineurin, a phosphoprotein serine/threonine phosphatase enzyme, in the regulation of many physiologic systems. Calcineurin mediates activation of lymphocytes, which play a role in immune response. Widely distributed in the central nervous system, calcinuerin also plays an important role in sensory neural function, via its role in the regulation of newly discovered 2-pore potassium channels, which greatly influence neuronal resting membrane potentials. Calcinuerin inhibition is the mechanism of action of immunomodulatory drugs such as cyclosporine and tacrolimus, which are widely used in transplantation medicine to prevent rejection. While important for immunosuppression, the use of calcineurin inhibitors has been associated with the development of a new pain syndrome called the calcineurin pain syndrome, which appears to be an untoward complication of the interruption of the physiologic function of calcineurin. This is a narrative review focusing on the epidemiology, pathophysiology, characterization of a newly recognized pain syndrome associated with the use of calcineurin inhibitors. The use of immunosuppressants however is associated with several well-known toxicities to which the calcineurin pain syndrome can be added. The development of this syndrome most likely involves altered nociceptive processing due to the effect of calcineurin inhibition on neuronal firing, as well as effects of calcineurin on vascular tone. The most striking aspect of the treatment of this syndrome is the response to calcium channel blockers, which suggest that the effects of calcineurin inhibition on vascular tone play an important role in the development of the calcineurin pain syndrome. The calcineurin syndrome is a newly recognized complication associated with the use of calcineurin inhibitors. There is no standard therapy at this time but anecdotal reports suggest the effectiveness of calcium channel blockers.

  17. Crystallization inhibitors for amorphous oxides

    International Nuclear Information System (INIS)

    Reznitskij, L.A.; Filippova, S.E.

    1993-01-01

    Data for the last 10 years, in which experimental results of studying the temperature stabilization of x-ray amorphous oxides (including R 3 Fe 5 O 12 R-rare earths, ZrO 2 , In 2 O 3 , Sc 2 O 3 ) and their solid solution are presented, are generalized. Processes of amorphous oxide crystallization with the production of simple oxides, solid solutions and chemical compounds with different polyhedral structure, are investigated. Energy and crystallochemical criteria for selecting the doping inhibitor-components stabilizing the amorphous state are ascertained, temperatures and enthalpies of amorpous oxide crystallization are determined, examination of certain provisions of iso,orphous miscibility theory is conducted

  18. Inhibitors of plant hormone transport

    Czech Academy of Sciences Publication Activity Database

    Klíma, Petr; Laňková, Martina; Zažímalová, Eva

    2016-01-01

    Roč. 253, č. 6 (2016), s. 1391-1404 ISSN 0033-183X R&D Projects: GA MŠk(CZ) LD15088 Institutional support: RVO:61389030 Keywords : polar auxin transport * acid-binding protein * gnom arf-gef * equilibrative nucleoside transporter * efflux carrier polarity * plasma-membrane-protein * cultured tobacco cells * arabidopsis-thaliana * gravitropic response * brefeldin-a * Plant hormones * Transport * Inhibitors * Auxin * Cytokinins * Strigolactones * Abscisic acid * Cell biology Subject RIV: ED - Physiology Impact factor: 2.870, year: 2016

  19. Laura: Soybean variety lacking Kunitz trypsin inhibitor

    Directory of Open Access Journals (Sweden)

    Srebrić Mirjana

    2010-01-01

    Full Text Available Grain of conventional soybean varieties requires heat processing to break down trypsin inhibitor's activity before using as food or animal feed. At the same time, protein denaturation and other qualitative changes occur in soybean grain, especially if the temperature of heating is not controlled. Two types of trypsin inhibitor were found in soybean grain the Kunitz trypsin inhibitor and the Bowman-Birk inhibitor. Mature grain of soybean Laura is lacking Kunitz trypsin inhibitor. Grain yield of variety Laura is equal to high yielding varieties from the maturity group I, where it belongs. Lacking of Kunitz-trypsin inhibitor makes soybean grain suitable for direct feeding in adult non ruminant animals without previous thermal processing. Grain of variety Laura can be processed for a shorter period of time than conventional soybeans. This way we save energy, and preserve valuable nutritional composition of soybean grain, which is of interest in industrial processing.

  20. Vanadium Compounds as PTP Inhibitors

    Directory of Open Access Journals (Sweden)

    Elsa Irving

    2017-12-01

    Full Text Available Phosphotyrosine signaling is regulated by the opposing actions of protein tyrosine kinases (PTKs and protein tyrosine phosphatases (PTPs. Here we discuss the potential of vanadium derivatives as PTP enzyme inhibitors and metallotherapeutics. We describe how vanadate in the V oxidized state is thought to inhibit PTPs, thus acting as a pan-inhibitor of this enzyme superfamily. We discuss recent developments in the biological and biochemical actions of more complex vanadium derivatives, including decavanadate and in particular the growing number of oxidovanadium compounds with organic ligands. Pre-clinical studies involving these compounds are discussed in the anti-diabetic and anti-cancer contexts. Although in many cases PTP inhibition has been implicated, it is also clear that many such compounds have further biochemical effects in cells. There also remain concerns surrounding off-target toxicities and long-term use of vanadium compounds in vivo in humans, hindering their progress through clinical trials. Despite these current misgivings, interest in these chemicals continues and many believe they could still have therapeutic potential. If so, we argue that this field would benefit from greater focus on improving the delivery and tissue targeting of vanadium compounds in order to minimize off-target toxicities. This may then harness their full therapeutic potential.

  1. Proton pump inhibitors and osteoporosis

    DEFF Research Database (Denmark)

    Andersen, Bjarne Nesgaard; Johansen, Per Birger; Abrahamsen, Bo

    2016-01-01

    PURPOSE OF REVIEW: The purpose of the review is to provide an update on recent advances in the evidence based on proton pump inhibitors (PPI) as a possible cause of osteoporosis and osteoporotic fractures. This review focuses, in particular, on new studies published in the last 18 months and a di......PURPOSE OF REVIEW: The purpose of the review is to provide an update on recent advances in the evidence based on proton pump inhibitors (PPI) as a possible cause of osteoporosis and osteoporotic fractures. This review focuses, in particular, on new studies published in the last 18 months...... and a discussion of these findings and how this has influenced our understanding of this association, the clinical impact and the underlying pathophysiology. RECENT FINDINGS: New studies have further strengthened existing evidence linking use of PPIs to osteoporosis. Short-term use does not appear to pose a lower...... risk than long-term use. There is a continued lack of conclusive studies identifying the pathogenesis. Direct effects on calcium absorption or on osteoblast or osteoclast action cannot at present plausibly explain the mechanism. SUMMARY: The use of PPIs is a risk factor for development of osteoporosis...

  2. Genome scan of clot lysis time and its association with thrombosis in a protein C deficient kindred

    Science.gov (United States)

    Meltzer, M.E.; Hasstedt, S.J.; Vossen, C.Y.; Callas, P.W.; de Groot, Ph.G.; Rosendaal, F.R.; Lisman, T.; Bovill, E.G.

    2011-01-01

    Summary Background Previously we found increased clot lysis time (CLT), as measured with a plasma-based assay, to increase the risk of venous thrombosis in two population-based case-control studies. Genes influencing CLT are yet unknown. Objectives and Patients/Methods We tested CLT as risk factor for venous thrombosis in Kindred Vermont II (n=346), a pedigree suffering from a high thrombosis risk, partially attributable to a type I protein C deficiency. Furthermore we tested for quantitative trait loci (QTL) for CLT using variance component linkage analysis. Results Protein C deficient family members had shorter CLT than non-deficient members (median CLT 67 versus 75 minutes). One standard deviation increase in CLT increased risk of venous thrombosis 2.4-fold in non-deficient family members. Protein C deficiency without elevated CLT increased risk 6.9-fold. Combining both risk factors yielded a 27.8-fold increased risk. Heritability of CLT was 42-52%. We found suggestive evidence of linkage on chromosome 11 (62 cM), partly explained by the prothrombin 20210A mutation, and on chromosome 13 (52 cM). Thrombin Activatable Fibrinolysis Inhibitor genotypes did not explain the variation in CLT. Conclusion Hypofibrinolysis appears to increase thrombosis risk in this family especially in combination with protein C deficiency. Protein C deficiency is associated with short CLT. CLT is partly genetically regulated. Suggestive QTL were found on chromosome 11 and 13. PMID:21575129

  3. TYROSINE KINASE INHIBITORS AND PREGNANCY

    Directory of Open Access Journals (Sweden)

    Elisabetta Abruzzese

    2014-04-01

    Full Text Available The management of patients with chronic myeloid leukemia (CML during pregnancy has became recently a matter of continuous debate.  The introduction of the Tyrosine Kinase Inhibitors (TKIs in clinical practice has dramatically changed the prognosis of CML patients.  Patients diagnosed in chronic phase can reasonably expect many years of excellent disease control and good quality of life, as well as a normal life expectancy.  This fact has come the necessity to address issues relating to fertility and pregnancy. Physicians are not infrequently being asked for advice regarding the need for, and or the appropriateness of, stopping treatment in order to conceive. In this report we will review the data published in terms of fertility, conception, pregnancy, pregnancy outcome and illness control for all the approved TKIs, as well as suggest how to manage a planned and/or unplanned pregnancy.

  4. Plasminogen activator inhibitor type 1 serum levels and 4G/5G gene polymorphism in morbidly obese Hispanic patients with non-alcoholic fatty liver disease.

    Science.gov (United States)

    Espino, Alberto; Villagrán, Andrea; Vollrath, Valeska; Hanckes, Paulina; Salas, Roberto; Farah, Andrea; Solís, Nancy; Pizarro, Margarita; Escalona, Alex; Boza, Camilo; Pérez, Gustavo; Carrasco, Gonzalo; Padilla, Oslando; Miquel, Juan Francisco; Nervi, Flavio; Chavez-Tapia, Norberto C; Arab, Juan Pablo; Alvarez-Lobos, Manuel; Arrese, Marco; Riquelme, Arnoldo

    2011-01-01

    The plasminogen activator inhibitor type-1 (PAI-1) has been implicated in the regulation of fibrinolysis and extracellular matrix components. The single base pair guanine insertion/deletion polymorphism (4G/5G) within the promoter region of the PAI-1 gene influences PAI-1 synthesis and may modulate hepatic fibrogenesis. To evaluate the influence of PAI-1 serum levels and 4G/5G polymorphism on the risk of liver fibrosis associated to non-alcoholic fatty liver disease (NAFLD) in morbidly obese patients. Case-control study of 50 obese patients undergoing bariatric surgery and 71 non-obese subjects matched by age and sex. Anthropometric and biochemical measurements were performed, including PAI-1 serum levels. Genomic DNA was obtained to assess the presence of 4G/5G polymorphism. BMI, insulinemia, triglycerides, HOMA-IR, hypertension and diabetes were significantly higher in obese patients compared to control subjects. PAI-1 serum levels observed in obese patients were significantly lower (10.63 ± 4.82) compared to controls (14.26 ± 11.4; p 5G promoter genotypes frequencies (p = 0.12). No differences were observed in PAI-1 plasma levels among obese patients with liver fibrosis (10.64 ± 4.35) compared to patients without liver fibrosis (10.61 ± 5.2; p = 0.985). PAI-1 4G/5G promoter genotypes frequencies were similar in patients with or without liver fibrosis associated to NASH (p = 0.6). Morbidly obese patients had significantly lower PAI-1 serum levels with similar PAI-1 4G/5G genotypes frequencies compared to non-obese subjects. The frequency of 4G/5G genotypes in Chilean Hispanic healthy subjects was similar to that described in other populations. No association was found between PAI-1 serum levels or 4G/5G genotype with liver fibrosis in obese patients.

  5. PARP Inhibitors in Ovarian Cancer.

    Science.gov (United States)

    Mittica, Gloria; Ghisoni, Eleonora; Giannone, Gaia; Genta, Sofia; Aglietta, Massimo; Sapino, Anna; Valabrega, Giorgio

    2018-03-05

    Treatment of Epithelial Ovarian Cancer (EOC), historically based on surgery and platinum doublet chemotherapy, is associated with high risk of relapse and poor prognosis for recurrent disease. In this landscape, the innovative treatment with PARP inhibitors (PARPis) demonstrated an outstanding activity in EOC, and is currently changing clinical practice in BRCA mutant patients. To highlight the mechanism of action, pharmacokinetics, clinical activity, indications and current strategies of development of Olaparib, Niraparib, Rucaparib, Talazoparib and Veliparib, the 5 most relevant PARPis. We performed a review on Pubmed using 'ovarian cancer' and the name of each PARPi (PARP inhibitor) discussed in the review as Medical Subject Headings (MeSH) keywords. The same search was performed on "clinicaltrial.gov" to identify ongoing clinical trials and on "google.com/patents" and "uspto.gov" for recent patents exploring PARPIs in ovarian cancer. Olaparib, Niraparib and Rucaparib are already approved for treatment of recurrent EOC and their indications are partially overlapping. Talazoparib and Veliparib are promising PARPis, but currently under investigation in early phase trials. Several studies are evaluating PARPis in monotherapy or in associations, in a wide range of settings (i.e. first line, neoadjuvant, platinum-sensitive and resistant disease). PARPis are valuable options in patients with recurrent ovarian cancer with promising activity in different stages of this disease. Further studies are required to better define optimal clinical settings, predictors of response beyond BRCA mutations and strategies to overcome secondary resistance of PARPis therapy in EOC. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  6. Discovery and SAR of hydantoin TACE inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Wensheng; Guo, Zhuyan; Orth, Peter; Madison, Vincent; Chen, Lei; Dai, Chaoyang; Feltz, Robert J.; Girijavallabhan, Vinay M.; Kim, Seong Heon; Kozlowski, Joseph A.; Lavey, Brian J.; Li, Dansu; Lundell, Daniel; Niu, Xiaoda; Piwinski, John J.; Popovici-Muller, Janeta; Rizvi, Razia; Rosner, Kristin E.; Shankar, Bandarpalle B.; Shih, Neng-Yang; Siddiqui, M.A.; Sun, J.; Tong, L.; Umland, S.; Wong, M.K.; Yang, D.Y.; Zhou, G. (Merck)

    2010-09-03

    We disclose inhibitors of TNF-{alpha} converting enzyme (TACE) designed around a hydantoin zinc binding moiety. Crystal structures of inhibitors bound to TACE revealed monodentate coordination of the hydantoin to the zinc. SAR, X-ray, and modeling designs are described. To our knowledge, these are the first reported X-ray structures of TACE with a hydantoin zinc ligand.

  7. Does plasminogen activator inhibitor-1 drive lymphangiogenesis?

    DEFF Research Database (Denmark)

    Bruyère, Françoise; Melen-Lamalle, Laurence; Blacher, Silvia

    2010-01-01

    The purpose of this study is to explore the function of plasminogen activator inhibitor-1 (PAI-1) during pathological lymphangiogenesis. PAI-1, the main physiological inhibitor of plasminogen activators is involved in pathological angiogenesis at least by controlling extracellular proteolysis and...

  8. Electrochemical Behaviour of Environmentally Friendly Inhibitor of ...

    African Journals Online (AJOL)

    Electrochemical Behaviour of Environmentally Friendly Inhibitor of Aloe Secundiflora Extract in Corrosion Control of Carbon Steel in Soft Water Media. ... The investigation was performed at different inhibitor concentrations under static and dynamic conditions using a Rotating Disk Electrode (RDE). The impedance and ...

  9. Histone deacetylase inhibitors (HDACIs: multitargeted anticancer agents

    Directory of Open Access Journals (Sweden)

    Ververis K

    2013-02-01

    Full Text Available Katherine Ververis,1 Alison Hiong,1 Tom C Karagiannis,1,* Paul V Licciardi2,*1Epigenomic Medicine, Alfred Medical Research and Education Precinct, 2Allergy and Immune Disorders, Murdoch Childrens Research Institute, Melbourne, VIC, Australia*These authors contributed equally to this workAbstract: Histone deacetylase (HDAC inhibitors are an emerging class of therapeutics with potential as anticancer drugs. The rationale for developing HDAC inhibitors (and other chromatin-modifying agents as anticancer therapies arose from the understanding that in addition to genetic mutations, epigenetic changes such as dysregulation of HDAC enzymes can alter phenotype and gene expression, disturb homeostasis, and contribute to neoplastic growth. The family of HDAC inhibitors is large and diverse. It includes a range of naturally occurring and synthetic compounds that differ in terms of structure, function, and specificity. HDAC inhibitors have multiple cell type-specific effects in vitro and in vivo, such as growth arrest, cell differentiation, and apoptosis in malignant cells. HDAC inhibitors have the potential to be used as monotherapies or in combination with other anticancer therapies. Currently, there are two HDAC inhibitors that have received approval from the US FDA for the treatment of cutaneous T-cell lymphoma: vorinostat (suberoylanilide hydroxamic acid, Zolinza and depsipeptide (romidepsin, Istodax. More recently, depsipeptide has also gained FDA approval for the treatment of peripheral T-cell lymphoma. Many more clinical trials assessing the effects of various HDAC inhibitors on hematological and solid malignancies are currently being conducted. Despite the proven anticancer effects of particular HDAC inhibitors against certain cancers, many aspects of HDAC enzymes and HDAC inhibitors are still not fully understood. Increasing our understanding of the effects of HDAC inhibitors, their targets and mechanisms of action will be critical for the

  10. Potential physiological role of plant glycosidase inhibitors

    DEFF Research Database (Denmark)

    Bellincampi, D.; Carmadella, L.; Delcour, J.A.

    2004-01-01

    Carbohydrate-active enzymes including glycosidases, transglycosidases, glycosyltransferases, polysaccharide lyases and carbohydrate esterases are responsible for the enzymatic processing of carbohydrates in plants. A number of carbohydrate-active enzymes are produced by microbial pathogens...... and insects responsible of severe crop losses. Plants have evolved proteinaceous inhibitors to modulate the activity of several of these enzymes. The continuing discovery of new inhibitors indicates that this research area is still unexplored and may lead to new exciting developments. To date, the role...... of the inhibitors is not completely understood. Here we review recent results obtained on the best characterised inhibitors, pointing to their possible biological role in vivo. Results recently obtained with plant transformation technology indicate that this class of inhibitors has potential biotechnological...

  11. The Wonders of Phosphodiesterase‑5 Inhibitors: A Majestic History

    African Journals Online (AJOL)

    A milestone in drug discovery was the selective inhibitors of. PDE‑5 that ... the pharmacotherapeutics of PDE‑5 inhibitors and the majestic history that led to their discovery. ..... including HIV protease inhibitors, ketoconazole, itraconazole,.

  12. Squash inhibitor family of serine proteinases

    International Nuclear Information System (INIS)

    Otlewski, J.; Krowarsch, D.

    1996-01-01

    Squash inhibitors of serine proteinases form an uniform family of small proteins. They are built of 27-33 amino-acid residues and cross-linked with three disulfide bridges. The reactive site peptide bond (P1-P1') is between residue 5 (Lys, Arg or Leu) and 6 (always Ile). High resolution X-ray structures are available for two squash inhibitors complexed with trypsin. NMR solution structures have also been determined for free inhibitors. The major structural motif is a distorted, triple-stranded antiparallel beta-sheet. A similar folding motif has been recently found in a number of proteins, including: conotoxins from fish-hunting snails, carboxypeptidase inhibitor from potato, kalata B1 polypeptide, and in some growth factors (e.g. nerve growth factor, transforming growth factor β2, platelet-derived growth factor). Squash inhibitors are highly stable and rigid proteins. They inhibit a number of serine proteinases: trypsin, plasmin, kallikrein, blood clotting factors: X a and XII a , cathepsin G. The inhibition spectrum can be much broadened if specific amino-acid substitutions are introduced, especially at residues which contact proteinase. Squash inhibitors inhibit proteinases via the standard mechanism. According to the mechanism, inhibitors are substrates which exhibit at neutral pH a high k cat /K m index for hydrolysis and resynthesis of the reactive site, and a low value of the hydrolysis constant. (author)

  13. Histone Deacetylase Inhibitors as Anticancer Drugs.

    Science.gov (United States)

    Eckschlager, Tomas; Plch, Johana; Stiborova, Marie; Hrabeta, Jan

    2017-07-01

    Carcinogenesis cannot be explained only by genetic alterations, but also involves epigenetic processes. Modification of histones by acetylation plays a key role in epigenetic regulation of gene expression and is controlled by the balance between histone deacetylases (HDAC) and histone acetyltransferases (HAT). HDAC inhibitors induce cancer cell cycle arrest, differentiation and cell death, reduce angiogenesis and modulate immune response. Mechanisms of anticancer effects of HDAC inhibitors are not uniform; they may be different and depend on the cancer type, HDAC inhibitors, doses, etc. HDAC inhibitors seem to be promising anti-cancer drugs particularly in the combination with other anti-cancer drugs and/or radiotherapy. HDAC inhibitors vorinostat, romidepsin and belinostat have been approved for some T-cell lymphoma and panobinostat for multiple myeloma. Other HDAC inhibitors are in clinical trials for the treatment of hematological and solid malignancies. The results of such studies are promising but further larger studies are needed. Because of the reversibility of epigenetic changes during cancer development, the potency of epigenetic therapies seems to be of great importance. Here, we summarize the data on different classes of HDAC inhibitors, mechanisms of their actions and discuss novel results of preclinical and clinical studies, including the combination with other therapeutic modalities.

  14. Histone Deacetylase Inhibitors as Anticancer Drugs

    Directory of Open Access Journals (Sweden)

    Tomas Eckschlager

    2017-07-01

    Full Text Available Carcinogenesis cannot be explained only by genetic alterations, but also involves epigenetic processes. Modification of histones by acetylation plays a key role in epigenetic regulation of gene expression and is controlled by the balance between histone deacetylases (HDAC and histone acetyltransferases (HAT. HDAC inhibitors induce cancer cell cycle arrest, differentiation and cell death, reduce angiogenesis and modulate immune response. Mechanisms of anticancer effects of HDAC inhibitors are not uniform; they may be different and depend on the cancer type, HDAC inhibitors, doses, etc. HDAC inhibitors seem to be promising anti-cancer drugs particularly in the combination with other anti-cancer drugs and/or radiotherapy. HDAC inhibitors vorinostat, romidepsin and belinostat have been approved for some T-cell lymphoma and panobinostat for multiple myeloma. Other HDAC inhibitors are in clinical trials for the treatment of hematological and solid malignancies. The results of such studies are promising but further larger studies are needed. Because of the reversibility of epigenetic changes during cancer development, the potency of epigenetic therapies seems to be of great importance. Here, we summarize the data on different classes of HDAC inhibitors, mechanisms of their actions and discuss novel results of preclinical and clinical studies, including the combination with other therapeutic modalities.

  15. Reverse transcriptase inhibitors as microbicides.

    Science.gov (United States)

    Lewi, Paul; Heeres, Jan; Ariën, Kevin; Venkatraj, Muthusamy; Joossens, Jurgen; Van der Veken, Pieter; Augustyns, Koen; Vanham, Guido

    2012-01-01

    The CAPRISA 004 study in South Africa has accelerated the development of vaginal and rectal microbicides containing antiretrovirals that target specific enzymes in the reproduction cycle of HIV, especially reverse transcriptase inhibitors (RTI). In this review we discuss the potential relevance of HIV-1 RTIs as microbicides, focusing in the nucleotide RTI tenofovir and six classes of nonnucleoside RTIs (including dapivirine, UC781, urea and thiourea PETTs, DABOs and a pyrimidinedione). Although tenofovir and dapivirine appear to be most advanced in clinical trials as potential microbicides, several issues remain unresolved, e.g., the importance of nonhuman primates as a "gatekeeper" for clinical trials, the emergence and spread of drug-resistant mutants, the combination of microbicides that target different phases of viral reproduction and the accessibility to microbicides in low-income countries. Thus, here we discuss the latest research on RTI as microbicides in the light of the continuing spread of the HIV pandemic from the point of view of medicinal chemistry, virological, and pharmaceutical studies.

  16. AZT as a telomerase inhibitor

    International Nuclear Information System (INIS)

    Gomez, Daniel E.; Armando, Romina G.; Alonso, Daniel F.

    2012-01-01

    Telomerase is a highly specialized reverse transcriptase (RT) and the maintenance of telomeric length is determined by this specific enzyme. The human holoenzyme telomerase is a ribonucleoprotein composed by a catalytic subunit, hTERT, an RNA component, hTR, and a group of associated proteins. Telomerase is normally expressed in embryonic cells and is repressed during adulthood. The enzyme is reexpressed in around 85% of solid tumors. This observation makes it a potential target for developing drugs that could be developed for therapeutic purposes. The identification of the hTERT as a functional catalytic RT prompted studies of inhibiting telomerase with the HIV RT inhibitor azidothymidine (AZT). Previously, we have demonstrated that AZT binds preferentially to telomeres, inhibits telomerase and enhances tumor cell senescence, and apoptosis after AZT treatment in breast mammary adenocarcinoma cells. Since then, several studies have considered AZT for telomerase inhibition and have led to potential clinical strategies for anticancer therapy. This review covers present thinking of the inhibition of telomerase by AZT and future treatment protocols using the drug.

  17. Proton pump inhibitors and gastroenteritis

    International Nuclear Information System (INIS)

    Hassing, Robert-Jan; Verbon, Annelies; Visser, Herman de; Hofman, Albert; Stricker, Bruno H.

    2016-01-01

    An association between proton pump inhibitor (PPI) therapy and bacterial gastroenteritis has been suggested as well as contradicted. The aim of this study was to examine the association between the use of PPIs and occurrence of bacterial gastroenteritis in the prospective Rotterdam Study. The Rotterdam Study is a population-based cohort study among 14,926 subjects aged 45 years and older with up to 24 years of follow-up. Analyses were performed with a generalized estimating equations method in participants who handed-in a diagnostic stool sample. Furthermore, a nested case–control analysis was performed using the total cohort as a reference group. A bacterial microorganism was isolated in 125 samples, whereas 1174 samples were culture negative. In the generalized estimating equations analysis, we found that participants with a bacterial gastroenteritis were more likely than controls to be current users of PPIs (adjusted OR 1.94; 95 % CI 1.15–3.25). Different sensitivity analyses did not change this result. A considerably higher effect was observed (adjusted OR 6.14; 95 % CI 3.81–9.91), using the total cohort as a reference in a nested case–control analysis. Current PPI therapy is associated with an increased risk of bacterial gastroenteritis. However, by reducing the risk of selection and information bias in our study design, we demonstrated that the effect is lower than previously assumed.

  18. ALK inhibitors, a pharmaceutical perspective

    Directory of Open Access Journals (Sweden)

    Arturo eGalvani

    2012-02-01

    Full Text Available In 2007, the ALK tyrosine kinase, already known to be translocated and activated in Anaplastic Large Cell Lymphoma, and a few other rare cancers, was described as a potential therapeutic target for a subset of non small-cell lung cancer (NSCLC patients. Clinical proof of concept, culminating in the recent approval by the FDA of the Pfizer drug Xalkori (crizotinib, formerly known as PF-02341066 followed in record time. The drug was approved together with a companion diagnostic, the Vysis ALK Break Apart FISH Probe Kit (Abbott Molecular, Inc. for detection of eligible patients. This remarkable example of the coming of age of personalized medicine in cancer therapy is hopefully only an auspice of things to come in this rapidly developing field. Perhaps unsurprisingly, however, the appearance of clinical acquired resistance to crizotinib has already been observed early on in clinical testing, with the identification of several ALK secondary point mutations which diminish drug efficacy, and which open the way for development of second-generation inhibitors. It is also emerging that acquired resistance to crizotinib may also occur through ALK-independent mechanisms, which still need to be elucidated in detail.

  19. SGLT2 Inhibitors May Predispose to Ketoacidosis.

    Science.gov (United States)

    Taylor, Simeon I; Blau, Jenny E; Rother, Kristina I

    2015-08-01

    Sodium glucose cotransporter 2 (SGLT2) inhibitors are antidiabetic drugs that increase urinary excretion of glucose, thereby improving glycemic control and promoting weight loss. Since approval of the first-in-class drug in 2013, data have emerged suggesting that these drugs increase the risk of diabetic ketoacidosis. In May 2015, the Food and Drug Administration issued a warning that SGLT2 inhibitors may lead to ketoacidosis. Using PubMed and Google, we conducted Boolean searches including terms related to ketone bodies or ketoacidosis with terms for SGLT2 inhibitors or phlorizin. Priority was assigned to publications that shed light on molecular mechanisms whereby SGLT2 inhibitors could affect ketone body metabolism. SGLT2 inhibitors trigger multiple mechanisms that could predispose to diabetic ketoacidosis. When SGLT2 inhibitors are combined with insulin, it is often necessary to decrease the insulin dose to avoid hypoglycemia. The lower dose of insulin may be insufficient to suppress lipolysis and ketogenesis. Furthermore, SGLT2 is expressed in pancreatic α-cells, and SGLT2 inhibitors promote glucagon secretion. Finally, phlorizin, a nonselective inhibitor of SGLT family transporters decreases urinary excretion of ketone bodies. A decrease in the renal clearance of ketone bodies could also increase the plasma ketone body levels. Based on the physiology of SGLT2 and the pharmacology of SGLT2 inhibitors, there are several biologically plausible mechanisms whereby this class of drugs has the potential to increase the risk of developing diabetic ketoacidosis. Future research should be directed toward identifying which patients are at greatest risk for this side effect and also to optimizing pharmacotherapy to minimize the risk to patients.

  20. Enzyme structure and interaction with inhibitors

    International Nuclear Information System (INIS)

    London, R.E.

    1983-01-01

    This article reviews some of the results of studies on the 13 C-labeled enzyme dihydrofolate reductase (DHFR). Nuclear magnetic resonance (NMR) techniques are used in combination with isotopic labeling to learn about the structure and dynamics of this enzyme. 13 C-labeling is used for the purpose of studying enzyme/substrate and enzyme/inhibitor interactions. A second set of studies with DHFR was designed to investigate the basis for the high affinity between the inhibitor methotrexate and DHFR. The label was placed on the inhibitor, rather than the enzyme

  1. An Updated Review of Tyrosinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Te-Sheng Chang

    2009-05-01

    Full Text Available Tyrosinase is a multifunctional, glycosylated, and copper-containing oxidase, which catalyzes the first two steps in mammalian melanogenesis and is responsible for enzymatic browning reactions in damaged fruits during post-harvest handling and processing. Neither hyperpigmentation in human skin nor enzymatic browning in fruits are desirable. These phenomena have encouraged researchers to seek new potent tyrosinase inhibitors for use in foods and cosmetics. This article surveys tyrosinase inhibitors newly discovered from natural and synthetic sources. The inhibitory strength is compared with that of a standard inhibitor, kojic acid, and their inhibitory mechanisms are discussed.

  2. Strategies for discontinuation of proton pump inhibitors

    DEFF Research Database (Denmark)

    Haastrup, Peter; Paulsen, Maja S; Begtrup, Luise M

    2014-01-01

    PURPOSE: Proton pump inhibitors (PPIs) are considered to be overprescribed. Consensus on how to attempt discontinuation is, however, lacking. We therefore conducted a systematic review of clinical studies on discontinuation of PPIs. METHODS: Systematic review based on clinical studies investigating...

  3. Predicting the Performance of Organic Corrosion Inhibitors

    Directory of Open Access Journals (Sweden)

    David A. Winkler

    2017-12-01

    Full Text Available The withdrawal of effective but toxic corrosion inhibitors has provided an impetus for the discovery of new, benign organic compounds to fill that role. Concurrently, developments in the high-throughput synthesis of organic compounds, the establishment of large libraries of available chemicals, accelerated corrosion inhibition testing technologies, and the increased capability of machine learning methods have made discovery of new corrosion inhibitors much faster and cheaper than it used to be. We summarize these technical developments in the corrosion inhibition field and describe how data-driven machine learning methods can generate models linking molecular properties to corrosion inhibition that can be used to predict the performance of materials not yet synthesized or tested. We briefly summarize the literature on quantitative structure–property relationships models of small organic molecule corrosion inhibitors. The success of these models provides a paradigm for rapid discovery of novel, effective corrosion inhibitors for a range of metals and alloys in diverse environments.

  4. Novel diamide-based inhibitors of IMPDH.

    Science.gov (United States)

    Gu, Henry H; Iwanowicz, Edwin J; Guo, Junqing; Watterson, Scott H; Shen, Zhongqi; Pitts, William J; Dhar, T G Murali; Fleener, Catherine A; Rouleau, Katherine; Sherbina, N Z; Witmer, Mark; Tredup, Jeffrey; Hollenbaugh, Diane

    2002-05-06

    A series of novel amide-based small molecule inhibitors of inosine monophosphate dehydrogenase is described. The synthesis and the structure-activity relationships (SARs) derived from in vitro studies are presented.

  5. Monoamine Oxidase B Inhibitors in Parkinson's Disease.

    Science.gov (United States)

    Dezsi, Livia; Vecsei, Laszlo

    2017-01-01

    Parkinson's disease (PD) is a neurodegenerative disorder with a prevalence increasing with age. Oxidative stress and glutamate toxicity are involved in its pathomechanism. There are still many unmet needs of PD patients, including the alleviation of motor fluctuations and dyskinesias, and the development of therapies with neuroprotective potential. To give an overview of the pharmacological properties, the efficacy and safety of the monoamine oxidase B (MAO-B) inhibitors in the treatment of PD, with special focus on the results of randomized clinical trials. A literature search was conducted in PubMed for 'PD treatment', 'MAO-B inhibitors', 'selegiline', 'rasagiline', 'safinamide' and 'clinical trials' with 'MAO-B inhibitors' in 'Parkinson' disease'. MAO-B inhibitors have a favorable pharmacokinetic profile, improve the dopamine deficient state and may have neuroprotective properties. Safinamide exhibits an anti-glutamatergic effect as well. When applied as monotherapy, MAO-B inhibitors provide a modest, but significant improvement of motor function and delay the need for levodopa. Rasagiline and safinamide were proven safe and effective when added to a dopamine agonist in early PD. As add-on to levodopa, MAO-B inhibitors significantly reduced off-time and were comparable in efficacy to COMT inhibitors. Improvements were achieved as regards certain non-motor symptoms as well. Due to the efficacy shown in clinical trials and their favorable side-effect profile, MAO-B inhibitors are valuable drugs in the treatment of PD. They are recommended as monotherapy in the early stages of the disease and as add-on therapy to levodopa in advanced PD. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  6. The effect of chemical anti-inhibitors on fibrinolytic enzymes and inhibitors

    DEFF Research Database (Denmark)

    Sidelmann, Johannes Jakobsen; Jespersen, J; Kluft, C

    1997-01-01

    proteases. We studied the influence of chemical anti-inhibitors (chloramine T, flufenamate, sodium lauryl sulfate, and methylamine) on fibrinolytic serine proteases and fibrinolytic enzyme inhibitors using the physiological substrate fibrin as plasmin substrate. Low concentrations of chloramine T (0.01 mmol......%) and plasminogen activators (apparent recovery > 200%). Sodium lauryl sulfate eliminates the major fibrinolytic enzyme inhibitors, but increases the activity of plasmin (apparent recovery > 200%) and plasminogen activator, urokinase type (apparent recovery 130%). Methylamine affects only plasmin inhibition. We...

  7. Development of Radiosensitizer using farnesyltransferase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jong Seok; Choe, Yong Kyung; Han, Mi Young; Kim, Kwang Dong [Korea Research Institute of Bioscience and Biotechnology, Taejon (Korea)

    1999-03-01

    We selected some compounds that were reported to have an activity of farneyltransferase inhibitor and tested the hypothesis that they might be used to radiosensitize cells transformed by ras oncogenes. The inhibition of ras processing using some, but not all, inhibitors resulted in higher levels of cell death after {gamma}-irradiation and increased radiosensitivity in H-ras-transformed NIH3T3 cells and MCF-10A human tumor cells. They did not induce additional cell death in control cells that doe not have ras mutation. Furthermore, the treatment of inhibitors alone induced a weak G0/G1 block, whereas inhibitors in combination with {gamma}-irradiation induced an additional enrichment in the G2/M phase of the cell cycle that typically represents irradiation-induced growth arrest. At present, the underling mechanism by which the farnesylltransferase inhibitors exert radiosensitizing effect is not known. In summary, our results suggest and lead to the possibility that some of farnesylation inhibitors may prove clinically useful not only as antitumor agents, but also radiosensitizers of tumors whose growth is dependent on ras function. (author). 15 refs., 10 figs., 4 tabs.

  8. Natural inhibitors of tumor-associated proteases

    International Nuclear Information System (INIS)

    Magdolen, U.; Krol, J.; Sato, S.; Schmitt, M.; Magdolen, V.; Krueger, A.; Mueller, M.M.; Sperl, S.

    2002-01-01

    The turnover and remodelling of extracellular matrix (ECM) is an essential part of many normal biological processes including development, morphogenesis, and wound healing. ECM turnover also occurs in severe pathological situations like artherosclerosis, fibrosis, tumor invasion and metastasis. The major proteases involved in this turnover are serine proteases (especially the urokinase-type plasminogen activator/plasmin system), matrix metalloproteases (a family of about 20 zinc-dependent endopeptidases including collagenases, gelatinases, stromelysins, and membrane-type metalloproteases), and cysteine proteases. In vivo, the activity of these proteases is tightly regulated in the extracellular space by zymogen activation and/or controlled inhibition. In the present review, we give an overview on the structure and biochemical properties of important tumor-associated protease inhibitors such as plasminogen activator inhibitor type 1 and type 2 (PAI-1, PAI-2), tissue inhibitors of metalloproteinases (TIMP-1, -2, -3, and -4), and the cysteine protease inhibitor cystatin C. Interestingly, some of these inhibitors of tumor-associated proteases display multiple functions which rather promote than inhibit tumor progression, when the presence of inhibitors in the tumor tissue is not balanced. (author)

  9. Emerging Corrosion Inhibitors for Interfacial Coating

    Directory of Open Access Journals (Sweden)

    Mona Taghavikish

    2017-12-01

    Full Text Available Corrosion is a deterioration of a metal due to reaction with environment. The use of corrosion inhibitors is one of the most effective ways of protecting metal surfaces against corrosion. Their effectiveness is related to the chemical composition, their molecular structures and affinities for adsorption on the metal surface. This review focuses on the potential of ionic liquid, polyionic liquid (PIL and graphene as promising corrosion inhibitors in emerging coatings due to their remarkable properties and various embedment or fabrication strategies. The review begins with a precise description of the synthesis, characterization and structure-property-performance relationship of such inhibitors for anti-corrosion coatings. It establishes a platform for the formation of new generation of PIL based coatings and shows that PIL corrosion inhibitors with various heteroatoms in different form can be employed for corrosion protection with higher barrier properties and protection of metal surface. However, such study is still in its infancy and there is significant scope to further develop new structures of PIL based corrosion inhibitors and coatings and study their behaviour in protection of metals. Besides, it is identified that the combination of ionic liquid, PIL and graphene could possibly contribute to the development of the ultimate corrosion inhibitor based coating.

  10. Discovery of natural mouse serum derived HIV-1 entry inhibitor(s).

    Science.gov (United States)

    Wei, M; Chen, Y; Xi, J; Ru, S; Ji, M; Zhang, D; Fang, Q; Tang, B

    Among rationally designed human immunodeficiency virus 1 (HIV-1) inhibitors, diverse natural factors have showed as potent anti-HIV activity in human blood. We have discovered that the boiled supernatant of healthy mouse serum could suppress HIV-1 entry, and exhibited reduced inhibitory activity after trypsin digestion. Further analysis demonstrated that only the fraction containing 10-25 K proteins could inhibit HIV-1 mediated cell-cell fusion. These results suggest that the 10-25 K protein(s) is novel natural HIV-1 entry inhibitor(s). Our findings provide important information about novel natural HIV entry inhibitors in mouse serum.

  11. Protease-activatable collagen targeting based on protein cyclization

    NARCIS (Netherlands)

    Breurken, M.; Lempens, E.H.M.; Merkx, M.

    2010-01-01

    Threading collagen through a protein needle: The collagen-binding protein CNA35 operates by wrapping itself around the collagen triple helix. By connecting the N and C termini through an MMP recognition sequence, a dual-specific MMP-sensitive collagen-targeting ligand is obtained that can be used

  12. Inactivation of proteinaceous protease inhibitors of soybeans by isolated fungi

    NARCIS (Netherlands)

    Meijer, M.M.T.; Spekking, W.T.J.; Sijtsma, L.; Bont, de J.A.M.

    1995-01-01

    Proteinaceous protease inhibitors, Kunitz Soybean Trypsin Inhibitor (KSTI) and Bowman Birk Inhibitor (BBI), in legume seeds reduce the digestibility of proteins in feed of monogastric animals. Enzymatic inactivation of these inhibitors will increase the nutritional value of the feed. The aim of this

  13. Combined effects of EGFR tyrosine kinase inhibitors and vATPase inhibitors in NSCLC cells

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyeon-Ok [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Hong, Sung-Eun [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Kim, Chang Soon [Department of Microbiological Engineering, Kon-Kuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 143–701 (Korea, Republic of); Park, Jin-Ah; Kim, Jin-Hee; Kim, Ji-Young; Kim, Bora [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Chang, Yoon Hwan; Hong, Seok-Il; Hong, Young Jun [Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Park, In-Chul, E-mail: parkic@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Lee, Jin Kyung, E-mail: jklee@kirams.re.kr [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of)

    2015-08-15

    Despite excellent initial clinical responses of non-small cell lung cancer (NSCLC) patients to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), many patients eventually develop resistance. According to a recent report, vacuolar H + ATPase (vATPase) is overexpressed and is associated with chemotherapy drug resistance in NSCLC. We investigated the combined effects of EGFR TKIs and vATPase inhibitors and their underlying mechanisms in the regulation of NSCLC cell death. We found that combined treatment with EGFR TKIs (erlotinib, gefitinib, or lapatinib) and vATPase inhibitors (bafilomycin A1 or concanamycin A) enhanced synergistic cell death compared to treatments with each drug alone. Treatment with bafilomycin A1 or concanamycin A led to the induction of Bnip3 expression in an Hif-1α dependent manner. Knock-down of Hif-1α or Bnip3 by siRNA further enhanced cell death induced by bafilomycin A1, suggesting that Hif-1α/Bnip3 induction promoted resistance to cell death induced by the vATPase inhibitors. EGFR TKIs suppressed Hif-1α and Bnip3 expression induced by the vATPase inhibitors, suggesting that they enhanced the sensitivity of the cells to these inhibitors by decreasing Hif-1α/Bnip3 expression. Taken together, we conclude that EGFR TKIs enhance the sensitivity of NSCLC cells to vATPase inhibitors by decreasing Hif-1α/Bnip3 expression. We suggest that combined treatment with EGFR TKIs and vATPase inhibitors is potentially effective for the treatment of NSCLC. - Highlights: • Co-treatment with EGFR TKIs and vATPase inhibitors induces synergistic cell death • EGFR TKIs enhance cell sensitivity to vATPase inhibitors via Hif-1α downregulation • Co-treatment of these inhibitors is potentially effective for the treatment of NSCLC.

  14. Screening of protein kinase inhibitors identifies PKC inhibitors as inhibitors of osteoclastic acid secretion and bone resorption

    Directory of Open Access Journals (Sweden)

    Boutin Jean A

    2010-10-01

    Full Text Available Abstract Background Bone resorption is initiated by osteoclastic acidification of the resorption lacunae. This process is mediated by secretion of protons through the V-ATPase and chloride through the chloride antiporter ClC-7. To shed light on the intracellular signalling controlling extracellular acidification, we screened a protein kinase inhibitor library in human osteoclasts. Methods Human osteoclasts were generated from CD14+ monocytes. The effect of different kinase inhibitors on lysosomal acidification in human osteoclasts was investigated using acridine orange for different incubation times (45 minutes, 4 and 24 hours. The inhibitors were tested in an acid influx assay using microsomes isolated from human osteoclasts. Bone resorption by human osteoclasts on bone slices was measured by calcium release. Cell viability was measured using AlamarBlue. Results Of the 51 compounds investigated only few inhibitors were positive in both acidification and resorption assays. Rottlerin, GF109203X, Hypericin and Ro31-8220 inhibited acid influx in microsomes and bone resorption, while Sphingosine and Palmitoyl-DL-carnitine-Cl showed low levels of inhibition. Rottlerin inhibited lysosomal acidification in human osteoclasts potently. Conclusions In conclusion, a group of inhibitors all indicated to inhibit PKC reduced acidification in human osteoclasts, and thereby bone resorption, indicating that acid secretion by osteoclasts may be specifically regulated by PKC in osteoclasts.

  15. In vitro and in vivo characterisation of the profibrinolytic effect of an inhibitory anti-rat TAFI nanobody.

    Science.gov (United States)

    Hendrickx, Maarten L V; Zatloukalova, Monika; Hassanzadeh-Ghassabeh, Gholamreza; Muyldermans, Serge; Gils, Ann; Declerck, Paul J

    2014-05-05

    One of the main disadvantages of current t-PA thrombolytic treatment is the increased bleeding risk. Upon activation, thrombin activatable fibrinolysis inhibitor (TAFI) is a very powerful antifibrinolytic enzyme. Therefore, co-administration of a TAFI inhibitor during thrombolysis could reduce the required t-PA dose without compromising the thrombolytic efficacy. In this study we generated and characterised a nanobody that is inhibitory towards rat TAFI and evaluated its profibrinolytic property in vitro and in vivo. Nanobody VHH-rTAFI-i81 inhibits (at a 16-fold molar ratio nanobody over TAFI) the thrombin/thrombomodulin (T/TM)-mediated activation of rat TAFI (rTAFI) by 83 ± 1.8% with an IC50 of 0.46 (molar ratio nanobody over TAFI). The affinity (KA) of VHH-rTAFI-i81 for rTAFI, as determined by surface plasmon resonance (Biacore®), is 2.5 ± 0.2 x 10(10) M(-1) and illustrates a very strong binding. In an in vitro clot lysis assay, administration of VHH-rTAFI-i81 strongly enhances the degree of lysis and reduces time to reach full lysis of t-PA-mediated clot lysis. Epitope mapping discloses that Lys392 is of primary importance for the nanobody/rTAFI interaction besides minor contributions of Tyr175 and Glu183. In vivo application of VHH-rTAFI-i81 in a tissue factor-induced mouse thromboembolism model significantly decreases fibrin deposition in the lungs in the absence of exogenous administered t-PA. Nanobody VHH-rTAFI-i81 is a very potent inhibitor of T/TM-mediated TAFI activation. Co-administration of this nanobody and t-PA enhances the fibrinolytic efficacy. In an in vivo mouse thromboembolism model, VHH-rTAFI-i81 reduces fibrin deposition in the lungs.

  16. SGLT2 Inhibitors and the Diabetic Kidney.

    Science.gov (United States)

    Fioretto, Paola; Zambon, Alberto; Rossato, Marco; Busetto, Luca; Vettor, Roberto

    2016-08-01

    Diabetic nephropathy (DN) is the most common cause of end-stage renal disease worldwide. Blood glucose and blood pressure control reduce the risk of developing this complication; however, once DN is established, it is only possible to slow progression. Sodium-glucose cotransporter 2 (SGLT2) inhibitors, the most recent glucose-lowering oral agents, may have the potential to exert nephroprotection not only through improving glycemic control but also through glucose-independent effects, such as blood pressure-lowering and direct renal effects. It is important to consider, however, that in patients with impaired renal function, given their mode of action, SGLT2 inhibitors are less effective in lowering blood glucose. In patients with high cardiovascular risk, the SGLT2 inhibitor empagliflozin lowered the rate of cardiovascular events, especially cardiovascular death, and substantially reduced important renal outcomes. Such benefits on DN could derive from effects beyond glycemia. Glomerular hyperfiltration is a potential risk factor for DN. In addition to the activation of the renin-angiotensin-aldosterone system, renal tubular factors, including SGLT2, contribute to glomerular hyperfiltration in diabetes. SGLT2 inhibitors reduce sodium reabsorption in the proximal tubule, causing, through tubuloglomerular feedback, afferent arteriole vasoconstriction and reduction in hyperfiltration. Experimental studies showed that SGLT2 inhibitors reduced hyperfiltration and decreased inflammatory and fibrotic responses of proximal tubular cells. SGLT2 inhibitors reduced glomerular hyperfiltration in patients with type 1 diabetes, and in patients with type 2 diabetes, they caused transient acute reductions in glomerular filtration rate, followed by a progressive recovery and stabilization of renal function. Interestingly, recent studies consistently demonstrated a reduction in albuminuria. Although these data are promising, only dedicated renal outcome trials will clarify whether

  17. Inhibitor chymotrypsynowy nasion wiechliny łąkowej (Poa pratensis [Chymotrypsin inhibitor from Poa pratensis seeds

    Directory of Open Access Journals (Sweden)

    I. Lorenc-Kubis

    2015-01-01

    Full Text Available A chymotrypsin inhibitor was isolated from Poa pratensis seeds. The inhibitor showed also antytriptic activity. It is a termostable protein, soluble in water, sodium chloride, but insoluble in 5% trichloracetic acid and 0.15 M sulphosalicylic acid.

  18. SGLT2 inhibitors: are they safe?

    Science.gov (United States)

    Filippas-Ntekouan, Sebastian; Filippatos, Theodosios D; Elisaf, Moses S

    2018-01-01

    Sodium-glucose linked transporter type 2 (SGLT2) inhibitors are a relatively new class of antidiabetic drugs with positive cardiovascular and kidney effects. The aim of this review is to present the safety issues associated with SGLT2 inhibitors. Urogenital infections are the most frequently encountered adverse events, although tend to be mild to moderate and are easily manageable with standard treatment. Although no increased acute kidney injury risk was evident in the major trials, the mechanism of action of these drugs requires caution when they are administered in patients with extracellular volume depletion or with drugs affecting renal hemodynamics. Canagliflozin raised the risk of amputations and the rate of fractures in the CANVAS trial, although more data are necessary before drawing definite conclusions. The risk of euglycemic diabetic ketoacidosis seems to be minimal when the drugs are prescribed properly. Regarding other adverse events, SGLT2 inhibitors do not increase the risk of hypoglycemia even when co-administered with insulin, but a decrease in the dose of sulphonylureas may be needed. The available data do not point to a causative role of SGLT2 inhibitors on malignancy risk, however, these drugs should be used with caution in patients with known hematuria or history of bladder cancer. SGLT2 inhibitors seem to be safe and effective in the treatment of diabetes but more studies are required to assess their long-term safety.

  19. Aromatase inhibitors and breast cancer prevention.

    Science.gov (United States)

    Litton, Jennifer Keating; Arun, Banu K; Brown, Powel H; Hortobagyi, Gabriel N

    2012-02-01

    Endocrine therapy with selective estrogen receptor modulators (SERMs) has been the mainstay of breast cancer prevention trials to date. The aromatase inhibitors, which inhibit the final chemical conversion of androgens to estrogens, have shown increased disease-free survival benefit over tamoxifen in patients with primary hormone receptor-positive breast cancer, as well as reducing the risk of developing contralateral breast cancers. The aromatase inhibitors are being actively evaluated as prevention agents for women with a history of ductal carcinoma in situ as well as for women who are considered to be at high risk for developing primary invasive breast cancer. This review evaluates the available prevention data, as evidenced by the decrease in contralateral breast cancers, when aromatase inhibitors are used in the adjuvant setting, as well as the emerging data of the aromatase inhibitors specifically tested in the prevention setting for women at high risk. Exemestane is a viable option for breast cancer prevention. We continue to await further follow-up on exemestane as well as other aromatase inhibitors in the prevention setting for women at high risk of developing breast cancer or with a history of ductal carcinoma in situ.

  20. Janus kinase inhibitors: jackpot or potluck?

    Directory of Open Access Journals (Sweden)

    Pavithran Keechilat

    2012-06-01

    Full Text Available The reports of a unique mutation in the Janus kinase-2 gene (JAK2 in polycythemia vera by several independent groups in 2005 quickly spurred the development of the Janus kinase inhibitors. In one of the great victories of translational research in recent times, the first smallmolecule Janus kinase inhibitor ruxolitinib entered a phase I trial in 2007. With the approval of ruxolitinib by the US Federal Drug Administration in November 2011 for high-risk and intermediate-2 risk myelofibrosis, a change in paradigm has occurred in the management of a subset of myeloproliferative neoplasms (MPN: primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. Whereas the current evidence for ruxolitinib only covers high-risk and intermediate-2 risk myelofibrosis, inhibitors with greater potency are likely to offer better disease control and survival advantage in patients belonging to these categories, and possibly to the low-risk and intermediate-1 risk categories of MPN as well. But use of the Janus kinase inhibitors also probably has certain disadvantages, such as toxicity, resistance, withdrawal phenomenon, non-reversal of histology, and an implausible goal of disease clone eradication, some of which could offset the gains. In spite of this, Janus kinase inhibitors are here to stay, and for use in more than just myeloproliferative neoplasms.

  1. A cyclic peptidic serine protease inhibitor

    DEFF Research Database (Denmark)

    Zhao, Baoyu; Xu, Peng; Jiang, Longguang

    2014-01-01

    Peptides are attracting increasing interest as protease inhibitors. Here, we demonstrate a new inhibitory mechanism and a new type of exosite interactions for a phage-displayed peptide library-derived competitive inhibitor, mupain-1 (CPAYSRYLDC), of the serine protease murine urokinase...... pocket, its carbonyl group aligning improperly relative to Ser195 and the oxyanion hole, explaining why the peptide is an inhibitor rather than a substrate. Substitution of the P1 Arg with novel unnatural Arg analogues with aliphatic or aromatic ring structures led to an increased affinity, depending......, in spite of a less favorable binding entropy and loss of a polar interaction. We conclude that increased flexibility of the peptide allows more favorable exosite interactions, which, in combination with the use of novel Arg analogues as P1 residues, can be used to manipulate the affinity and specificity...

  2. SGLT-2 Inhibitors and Cardiovascular Risk

    DEFF Research Database (Denmark)

    Cavender, Matthew A; Norhammar, Anna; Birkeland, Kåre I

    2018-01-01

    BACKGROUND: Prior studies found patients treated with sodium-glucose co-transporter-2 inhibitors (SGLT-2i) had lower rates of death and heart failure (HF). Whether the benefits of SGLT-2i vary based upon the presence of cardiovascular disease (CVD) is unknown. OBJECTIVES: This study sought...... to determine the association between initiation of SGLT-2i therapy and HF or death in patients with and without CVD. METHODS: The CVD-REAL (Comparative Effectiveness of Cardiovascular Outcomes in New Users of SGLT-2 Inhibitors) study was a multinational, observational study in which adults with type 2 diabetes...... evidence regarding the benefit of SGLT-2i in patients without established CVD. (Comparative Effectiveness of Cardiovascular Outcomes in New Users of SGLT-2 Inhibitors [CVD-REAL]; NCT02993614)....

  3. New halogenated phenylcoumarins as tyrosinase inhibitors.

    Science.gov (United States)

    Matos, Maria João; Santana, Lourdes; Uriarte, Eugenio; Delogu, Giovanna; Corda, Marcella; Fadda, Maria Benedetta; Era, Benedetta; Fais, Antonella

    2011-06-01

    With the aim to find out structural features for the tyrosinase inhibitory activity, in the present communication we report the synthesis and pharmacological evaluation of a new series of phenylcoumarin derivatives with different number of hydroxyl or ether groups and bromo substituent in the scaffold. The synthesized compounds 5-12 were evaluated as mushroom tyrosinase inhibitors showing, two of them, lower IC(50) than the umbelliferone. Compound 12 (IC(50)=215 μM) is the best tyrosinase inhibitor of this series. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Green inhibitors. Rare Earth based systems

    International Nuclear Information System (INIS)

    Aballe, A.; Bethencourt, M.; Botana, F.J.; Perez, J.; Rodriguez, M.A.; Marcos, M.

    1997-01-01

    Lanthanum, Cerium and Samarium chlorides have been investigated as uniform and pitting corrosion inhibitors of AISI 434 and AISI 304 stainless steels and AA 5083 Al-Mg alloy in 3.5% Na Cl aerated aqueous solutions. Their inhibitor power was evaluated by using electrochemical techniques such as Linear and Cyclic Polarisation. In each case, the highest protection degree was found in the solution dropped with 500 ppm of CeCl 3 . Similar results were obtained for additions of 500 ppm of LaCl 3 . Scanning Electron Microscopy and Energy Dispersive Spectroscopy allowed us to confirm the cathodic nature of the inhibition process. (Author) 27 refs

  5. 2-Aminobenzimidazoles as potent Aurora kinase inhibitors.

    Science.gov (United States)

    Zhong, Min; Bui, Minna; Shen, Wang; Baskaran, Subramanian; Allen, Darin A; Elling, Robert A; Flanagan, W Michael; Fung, Amy D; Hanan, Emily J; Harris, Shannon O; Heumann, Stacey A; Hoch, Ute; Ivy, Sheryl N; Jacobs, Jeffrey W; Lam, Stuart; Lee, Heman; McDowell, Robert S; Oslob, Johan D; Purkey, Hans E; Romanowski, Michael J; Silverman, Jeffrey A; Tangonan, Bradley T; Taverna, Pietro; Yang, Wenjin; Yoburn, Josh C; Yu, Chul H; Zimmerman, Kristin M; O'Brien, Tom; Lew, Willard

    2009-09-01

    This Letter describes the discovery and key structure-activity relationship (SAR) of a series of 2-aminobenzimidazoles as potent Aurora kinase inhibitors. 2-Aminobenzimidazole serves as a bioisostere of the biaryl urea residue of SNS-314 (1c), which is a potent Aurora kinase inhibitor and entered clinical testing in patients with solid tumors. Compared to SNS-314, this series of compounds offers better aqueous solubility while retaining comparable in vitro potency in biochemical and cell-based assays; in particular, 6m has also demonstrated a comparable mouse iv PK profile to SNS-314.

  6. Synergistic apoptosis induction in leukemic cells by the phosphatase inhibitor salubrinal and proteasome inhibitors.

    Directory of Open Access Journals (Sweden)

    Hannes C A Drexler

    Full Text Available Cells adapt to endoplasmic reticulum (ER-stress by arresting global protein synthesis while simultaneously activating specific transcription factors and their downstream targets. These processes are mediated in part by the phosphorylation-dependent inactivation of the translation initiation factor eIF2alpha. Following restoration of homeostasis protein synthesis is resumed when the serine/threonine-protein phosphatase PP1 dephosphorylates and reactivates eIF2alpha. Proteasome inhibitors, used to treat multiple myeloma patients evoke ER-stress and apoptosis by blocking the ER-associated degradation of misfolded proteins (ERAD, however, the role of eIF2alpha phosphorylation in leukemic cells under conditions of proteasome inhibitor-mediated ER stress is currently unclear.Bcr-Abl-positive and negative leukemic cell lines were used to investigate the functional implications of PP1-related phosphatase activities on eIF2alpha phosphorylation in proteasome inhibitor-mediated ER stress and apoptosis. Rather unexpectedly, salubrinal, a recently identified PP1 inhibitor capable to protect against ER stress in various model systems, strongly synergized with proteasome inhibitors to augment apoptotic death of different leukemic cell lines. Salubrinal treatment did not affect the phosphorlyation status of eIF2alpha. Furthermore, the proapoptotic effect of salubrinal occurred independently from the chemical nature of the proteasome inhibitor, was recapitulated by a second unrelated phosphatase inhibitor and was unaffected by overexpression of a dominant negative eIF2alpha S51A variant that can not be phosphorylated. Salubrinal further aggravated ER-stress and proteotoxicity inflicted by the proteasome inhibitors on the leukemic cells since characteristic ER stress responses, such as ATF4 and CHOP synthesis, XBP1 splicing, activation of MAP kinases and eventually apoptosis were efficiently abrogated by the translational inhibitor cycloheximide.Although PP1

  7. Structural Characterization of LRRK2 Inhibitors

    NARCIS (Netherlands)

    Gilsbach, Bernd K; Messias, Ana C; Ito, Genta; Sattler, Michael; Alessi, Dario R; Wittinghofer, Alfred; Kortholt, Arjan

    2015-01-01

    Kinase inhibition is considered to be an important therapeutic target for LRRK2 mediated Parkinson's disease (PD). Many LRRK2 kinase inhibitors have been reported but have yet to be optimized in order to qualify as drug candidates for the treatment of the disease. In order to start a

  8. Rational Design of Rho Protein Inhibitors

    National Research Council Canada - National Science Library

    Rojas, Rafael J

    2006-01-01

    ... nucleotide exchange factors (RhoGEFs). We have developed a high throughput screening strategy identify novel inhibitors of Rho activation are currently following up on several compounds which appear to selectively inhibit Rho activation. These compounds may form the basis of future drug development strategies for the treatment of metastatic breast cancer.

  9. Rational Design of Rho Protein Inhibitors

    National Research Council Canada - National Science Library

    Rojas, Rafael J

    2005-01-01

    ... nucleotide exchange factors (RhoGEFs). We have developed a high throughput screening strategy identify novel inhibitors of Rho activation are currently following up on several compounds which appear to selectively inhibit Rho activation. These compounds may form the basis of future drug development strategies for the treatment of metastatic breast cancer.

  10. [Mechanisms and efficacy of SGLT2 inhibitors].

    Science.gov (United States)

    Shiba, Teruo

    2015-03-01

    SGLT2 is a low affinity, high capacity glucose co-transporter, almost exclusively expressed in the kidney cortex. Inhibition of SGLT2 has been shown to increase the daily 50g or more urinary glucose excretion, as compared to placebo, leading to a reduction in blood glucose levels and indicated only for the treatment of type 2 diabetes. In Japan 6 species of SGLT2 inhibitors have already been sold and reported to results in a decrease of FPG by 14.4 to 45.8 (mg/dL), in a reduction of HbA1c by 0.35 to 1.24% and in loss of body weight by 1.29 to 2.50(kg). There is less effect of the SGLT2 inhibitor in diabetic subjects with renal impairment and the reduction in HbA1c and FPG will be approximately half of the average in those with 30 ≤ eGFR ≤ 59. The position of SGLT2 inhibitors would be considered as the drug administered in combination or add-on therapy when the young obese type 2 diabetics without renal impairment has not yet reached to the glycemic target with other drugs although in AACE consensus statement of 2013, it has been shelved for inexperienced use with respect to the positioning of the SGLT2 inhibitors.

  11. Th17 Inhibitors in Active Psoriatic Arthritis

    DEFF Research Database (Denmark)

    Naik, Girish S; Ming, Wai K; Magodoro, Itai M

    2018-01-01

    BACKGROUND: Several biologics targeting the Th17 pathway have been developed for the treatment of psoriatic arthritis (PsA), a disabling disease with moderate response and an increased incidence of serious infections to first-line biologics (TNF-α antagonists). Th17 inhibitors could replace TNF-α...

  12. Vildagliptin: the first innovative DDP-4 inhibitor

    Directory of Open Access Journals (Sweden)

    Edvin Villkhauer

    2010-09-01

    Full Text Available A review of the main stages of investigation undertaken by Novartis Pharmaceuticals in search of a new molecule for the treatment of type 2 diabetesmellitus, dipeptidyl peptidase-4 (DPP-4 inhibitor (Vildaglyptin. The data on specificity and selectivity of the action of this molecule are presentedalong with the results of its comparison with another agent of this group (sitagliptin.

  13. Curcumin derivatives as HIV-1 protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R. [Univ. of California, San Francisco, CA (United States)

    1993-12-31

    Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.

  14. Dissolution properties of cerium dibutylphosphate corrosion inhibitors

    NARCIS (Netherlands)

    Soestbergen, van M.; Erich, S.J.F.; Huinink, H.P.; Adan, O.C.G.

    2013-01-01

    The corrosion inhibitor cerium dibutylphosphate, Ce(dbp)3, prevents corrosion by cerium and dbp deposition at the alkaline cathode and acidic anode respectively. The pH dependent Ce(dbp)3 solubility seems to play an essential role in the inhibition degree. We found that Ce(dbp)3 scarcely dissolves

  15. SEARCH OF NEW SYNTHETIC INHIBITORS OF TYROSINASE

    Directory of Open Access Journals (Sweden)

    Yu. Shesterenko

    2017-11-01

    Full Text Available Melanin pigmentation of skin plays the most important role in the protection of organism against UV-irradiation, but the excessive accumulation of melanin brings to toxic melanodermia, melasma, lentigo and other skin lesions. Tyrosinase is the key enzyme of skin melanin pigment biosynthesis. In spite of certain progress in investigation of natural and synthetic tyrosinase inhibitors, actuality of such studies is of a high level, because the existing inhibitors are in some cases unstable, expensive, toxic, requires complex methods of synthesis or isolation from natural sources. The aim of the work is screening of new tyrosinase inhibitors, using the enzyme, isolated from Agaricus bisporus. Tyrosinase was isolated from Agaricus bisporus mushrooms by a modified method. It was found, that the introduction of polyethylene glycol 4000 in the extraction process promotes 3-fold reduction of polyphenol content, which leads to increase purity of enzyme with an increase in its activity by 25%. A search for new tyrosinase inhibitors among a wide range of compounds, including derivatives of 3-chloro-1,4-naphthoquinone, isatin, 3-hydroxy-2-naphthoic acid, etc was conducted. The studied substances did not displayed inhibitory effect at concentration of 0,1-0,5 mmol/dm3.

  16. Peptide aldehyde inhibitors of bacterial peptide deformylases.

    Science.gov (United States)

    Durand, D J; Gordon Green, B; O'Connell, J F; Grant, S K

    1999-07-15

    Bacterial peptide deformylases (PDF, EC 3.5.1.27) are metalloenzymes that cleave the N-formyl groups from N-blocked methionine polypeptides. Peptide aldehydes containing a methional or norleucinal inhibited recombinant peptide deformylase from gram-negative Escherichia coli and gram-positive Bacillus subtilis. The most potent inhibitor was calpeptin, N-CBZ-Leu-norleucinal, which was a competitive inhibitor of the zinc-containing metalloenzymes, E. coli and B. subtilis PDF with Ki values of 26.0 and 55.6 microM, respectively. Cobalt-substituted E. coli and B. subtilis deformylases were also inhibited by these aldehydes with Ki values for calpeptin of 9.5 and 12.4 microM, respectively. Distinct spectral changes were observed upon binding of calpeptin to the Co(II)-deformylases, consistent with the noncovalent binding of the inhibitor rather than the formation of a covalent complex. In contrast, the chelator 1,10-phenanthroline caused the time-dependent inhibition of B. subtilis Co(II)-PDF activity with the loss of the active site metal. The fact that calpeptin was nearly equipotent against deformylases from both gram-negative and gram-positive bacterial sources lends further support to the idea that a single deformylase inhibitor might have broad-spectrum antibacterial activity. Copyright 1999 Academic Press.

  17. Immune checkpoint inhibitors for metastatic bladder cancer.

    Science.gov (United States)

    Massari, Francesco; Di Nunno, Vincenzo; Cubelli, Marta; Santoni, Matteo; Fiorentino, Michelangelo; Montironi, Rodolfo; Cheng, Liang; Lopez-Beltran, Anto; Battelli, Nicola; Ardizzoni, Andrea

    2018-03-01

    Chemotherapy has represented the standard therapy for unresectable or metastatic urothelial carcinoma for more than 20 years. The growing knowledge of the interaction between tumour and immune system has led to the advent of new classes of drugs, the immune-checkpoints inhibitors, which are intended to change the current scenario. To date, immunotherapy is able to improve the overall responses and survival. Moreover, thanks to its safety profile immune-checkpoint inhibitors could be proposed also to patients unfit for standard chemotherapy. No doubts that these agents have started a revolution expected for years, but despite this encouraging results it appears clear that not all subjects respond to these agents and requiring the development of reliable predictive response factors able to isolate patients who can more benefit from these treatments as well as new strategies aimed to improve immunotherapy clinical outcome. In this review we describe the active or ongoing clinical trials involving Programmed Death Ligand 1 (PD-L1), Programmed Death receptor 1 (PD-1) and Cytotoxic-T Lymphocyte Antigen 4 (CTLA 4) inhibitors in urothelial carcinoma focusing our attention on the developing new immune-agents and combination strategies with immune-checkpoint inhibitors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Current and Novel Inhibitors of HIV Protease

    Czech Academy of Sciences Publication Activity Database

    Pokorná, Jana; Machala, L.; Řezáčová, Pavlína; Konvalinka, Jan

    2009-01-01

    Roč. 1, č. 3 (2009), s. 1209-1239 ISSN 1999-4915 R&D Projects: GA MŠk 1M0508 Grant - others:GA AV ČR(CZ) IAAX00320901 Program:IA Institutional research plan: CEZ:AV0Z40550506 Keywords : HIV protease * protease inhibitor * HAART Subject RIV: CE - Biochemistry

  19. Proton pump inhibitors affect the gut microbiome

    NARCIS (Netherlands)

    Imhann, Floris; Bonder, Marc Jan; Vich Vila, Arnau; Fu, Jingyuan; Mujagic, Zlatan; Vork, Lisa; Feenstra, Ettje T.; Jankipersadsing, Soesma A; Cenit, Maria Carmen; Harmsen, Hermie J M; Dijkstra, Gerard; Franke, Lude; Xavier, Ramnik J; Jonkers, Daisy; Wijmenga, Cisca; Weersma, Rinse K; Zhernakova, Alexandra

    BACKGROUND AND AIMS: Proton pump inhibitors (PPIs) are among the top 10 most widely used drugs in the world. PPI use has been associated with an increased risk of enteric infections, most notably Clostridium difficile. The gut microbiome plays an important role in enteric infections, by resisting or

  20. Pharmacological caspase inhibitors: Research towards therapeutic perspectives

    Czech Academy of Sciences Publication Activity Database

    Kudělová, J.; Fleischmannová, J.; Adamová, E.; Matalová, Eva

    2015-01-01

    Roč. 66, č. 4 (2015), s. 473-482 ISSN 0867-5910 R&D Projects: GA ČR(CZ) GA14-28254S Institutional support: RVO:68081715 Keywords : caspase * caspase inhibitor * apoptosis Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.804, year: 2015

  1. Pharmacological caspase inhibitors: Research towards therapeutic perspectives

    Czech Academy of Sciences Publication Activity Database

    Kudělová, J.; Fleischmannová, Jana; Adamová, Eva; Matalová, Eva

    2015-01-01

    Roč. 66, č. 4 (2015), s. 473-482 ISSN 0867-5910 R&D Projects: GA ČR GB14-37368G Institutional support: RVO:67985904 Keywords : caspase * caspase inhibitor * apoptosis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.804, year: 2015

  2. Discovery of inhibitors of bacterial histidine kinases

    NARCIS (Netherlands)

    Velikova, N.R.

    2014-01-01

    Discovery of Inhibitors of Bacterial Histidine Kinases Summary

    The thesis is on novel antibacterial drug discovery (http://youtu.be/NRMWOGgeysM). Using structure-based and fragment-based drug discovery approach, we have identified small-molecule histidine-kinase

  3. Novel peptide-based protease inhibitors

    DEFF Research Database (Denmark)

    Roodbeen, Renée

    of novel peptide-based protease inhibitors, efforts were made towards improved methods for peptide synthesis. The coupling of Fmoc-amino acids onto N-methylated peptidyl resins was investigated. These couplings can be low yielding and the effect of the use of microwave heating combined with the coupling...

  4. Oestrogen, testosterone, cytotoxin and cholinesterase inhibitor ...

    African Journals Online (AJOL)

    Oestrogen, testosterone, cytotoxin and cholinesterase inhibitor removal during reclamation of sewage to drinking water. ... Risks associated with sewage effluent and reclaimed sewage should be closely monitored; therefore water at the Gammams Sewage Treatment Plant (GSTP) inlet and outlet, as well as reclaimed water ...

  5. Discovery and Evaluation of Anti-Fibrinolytic Plasmin Inhibitors Derived from 5-(4-Piperidyl)isoxazol-3-ol (4-PIOL)

    DEFF Research Database (Denmark)

    Schmidt, Thomas C.; Eriksson, Per-Olof; Gustafsson, David

    2017-01-01

    Inhibition of plasmin has been found to effectively reduce fibrinolysis and to avoid hemorrhage. This can be achieved by addressing its kringle 1 domain with the known drug and lysine analogue tranexamic acid. Guided by shape similarities toward a previously discovered lead compound, 5-(4-piperidyl...

  6. Dry eye syndrome in aromatase inhibitor users.

    Science.gov (United States)

    Turaka, Kiran; Nottage, Jennifer M; Hammersmith, Kristin M; Nagra, Parveen K; Rapuano, Christopher J

    2013-04-01

    Aromatase inhibitors are frequently used as an adjuvant therapy in the treatment of breast cancer. We observed that several patients taking aromatase inhibitors presented with severe dry eye symptoms, and we investigated whether there is a relationship between aromatase inhibitors and dry eyes in these patients. Retrospective chart review. Forty-one women. A computerized search of health records was performed to identify patients using anastrazole, letrozole and exemestane seen by the Cornea Service from August 2008 to March 2011. The results were compared with age-matched controls. Ocular surface changes among aromatase inhibitors users. Of the 41 women, 39 were Caucasians. Thirty-nine patients had breast cancer (95%), one patient had ovarian cancer (2.5%) and one had an unknown primary cancer. Mean age was 68 ± 11.3 years (range 47-95). Most common presenting symptoms were blurred vision in 28 (68%) patients, irritation/foreign body sensation in 12 (29%) patients, redness in 9 (22%) patients, tearing in 6 (22%) patients and photosensitivity in 2 (5%) patients. Mean Schirmer's test measurement was 11 ± 5.8 mm (range 0.5-20 mm). Blepharitis was noted in 68 of 82 eyes (73%), decreased or poor tear function in 24 eyes (29%), conjunctival injection in 18 eyes (22%) and superficial punctate keratitis in 12 eyes (29%). Among an age-matched population (45-95 years), dry eye syndrome was found in only 9.5% of patients. Because the prevalence of ocular surface disease signs and symptoms appears to be higher in study group than control patients, aromatase inhibitors might be a contributing factor to the dry eye symptoms. © 2012 The Authors. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

  7. RENAL SAFETY OF PROTON PUMP INHIBITORS

    Directory of Open Access Journals (Sweden)

    A. I. Dyadyk

    2017-01-01

    Full Text Available Proton pump inhibitors are a widely used in clinical practice, and are taken by millions of patients around the world for a long time. While proton pump inhibitors are well-tolerated class of drugs, the number of publications has been raised about adverse renal effects, specially their association with acute tubulointerstitial nephritis. It is one of the leading causes of acute renal injury and have catastrophic long-term consequences called chronic kidney disease. In this review, we consider epidemiology, pathogenesis, diagnostic criteria (including biopsy and morphological pattern, clinical manifestations and treatment of proton pump inhibitors-induced acute tubulointerstitial nephritis. A subclinical course without classical manifestations of a cell-mediated hypersensitivity reaction (fever, skin rash, eosinophilia, arthralgia is characteristic of acute tubulointerstitial nephritis. Increased serum creatinine, decreased glomerular filtration rate, electrolyte disorders, pathological changes in urine tests are not highly specific indicators, but allow to suspect the development of acute tubulointerstitial nephritis. The “gold” standard of diagnosis is the intravital morphological examination of the kidney tissue. Timely diagnosis and immediate discontinuation of the potentially causative drug is the mainstay of therapy and the first necessary step in the early management of suspected or biopsy-proven drug-induced acute tubulointerstitial nephritis. The usage of proton pump inhibitors should be performed only on strict indications with optimal duration of treatment and careful monitoring of kidney function. Multiple comorbidities (older age, heart failure, diabetes, cirrhosis, chronic kidney disease, hypovolemia increase potential nephrotoxicity. Awareness of this iatrogenic complication will improve diagnosis of proton pump inhibitors-induced acute tubulointerstitial nephritis by multidisciplinary specialists and increase the possibility

  8. Cost of care of haemophilia with inhibitors.

    Science.gov (United States)

    Di Minno, M N D; Di Minno, G; Di Capua, M; Cerbone, A M; Coppola, A

    2010-01-01

    In Western countries, the treatment of patients with inhibitors is presently the most challenging and serious issue in haemophilia management, direct costs of clotting factor concentrates accounting for >98% of the highest economic burden absorbed for the healthcare of patients in this setting. Being designed to address questions of resource allocation and effectiveness, decision models are the golden standard to reliably assess the overall economic implications of haemophilia with inhibitors in terms of mortality, bleeding-related morbidity, and severity of arthropathy. However, presently, most data analyses stem from retrospective short-term evaluations, that only allow for the analysis of direct health costs. In the setting of chronic diseases, the cost-utility analysis, that takes into account the beneficial effects of a given treatment/healthcare intervention in terms of health-related quality of life, is likely to be the most appropriate approach. To calculate net benefits, the quality adjusted life year, that significantly reflects such health gain, has to be compared with specific economic impacts. Differences in data sources, in medical practice and/or in healthcare systems and costs, imply that most current pharmacoeconomic analyses are confined to a narrow healthcare payer perspective. Long-term/lifetime prospective or observational studies, devoted to a careful definition of when to start a treatment; of regimens (dose and type of product) to employ, and of inhibitor population (children/adults, low-responding/high responding inhibitors) to study, are thus urgently needed to allow for newer insights, based on reliable data sources into resource allocation, effectiveness and cost-utility analysis in the treatment of haemophiliacs with inhibitors.

  9. ROS inhibitor N-acetyl-L-cysteine antagonizes the activity of proteasome inhibitors.

    Science.gov (United States)

    Halasi, Marianna; Wang, Ming; Chavan, Tanmay S; Gaponenko, Vadim; Hay, Nissim; Gartel, Andrei L

    2013-09-01

    NAC (N-acetyl-L-cysteine) is commonly used to identify and test ROS (reactive oxygen species) inducers, and to inhibit ROS. In the present study, we identified inhibition of proteasome inhibitors as a novel activity of NAC. Both NAC and catalase, another known scavenger of ROS, similarly inhibited ROS levels and apoptosis associated with H₂O₂. However, only NAC, and not catalase or another ROS scavenger Trolox, was able to prevent effects linked to proteasome inhibition, such as protein stabilization, apoptosis and accumulation of ubiquitin conjugates. These observations suggest that NAC has a dual activity as an inhibitor of ROS and proteasome inhibitors. Recently, NAC was used as a ROS inhibitor to functionally characterize a novel anticancer compound, piperlongumine, leading to its description as a ROS inducer. In contrast, our own experiments showed that this compound depicts features of proteasome inhibitors including suppression of FOXM1 (Forkhead box protein M1), stabilization of cellular proteins, induction of ROS-independent apoptosis and enhanced accumulation of ubiquitin conjugates. In addition, NAC, but not catalase or Trolox, interfered with the activity of piperlongumine, further supporting that piperlongumine is a proteasome inhibitor. Most importantly, we showed that NAC, but not other ROS scavengers, directly binds to proteasome inhibitors. To our knowledge, NAC is the first known compound that directly interacts with and antagonizes the activity of proteasome inhibitors. Taken together, the findings of the present study suggest that, as a result of the dual nature of NAC, data interpretation might not be straightforward when NAC is utilized as an antioxidant to demonstrate ROS involvement in drug-induced apoptosis.

  10. Cytogenetic study of Ascaris trypsin inhibitor in cultured human ...

    Indian Academy of Sciences (India)

    2009-04-01

    Apr 1, 2009 ... Although the physical and chemical properties of Ascaris trypsin inhibitors ... male of Ascaris suum according to the method of Pudles and. Rola (1967). ..... inhibitor isolated from Ascaris resulted in the appearance of dominant ...

  11. SGLT2 inhibitors: molecular design and potential differences in effect.

    Science.gov (United States)

    Isaji, Masayuki

    2011-03-01

    The physiological and pathological handling of glucose via sodium-glucose cotransporter-2 (SGLT2) in the kidneys has been evolving, and SGLT2 inhibitors have been focused upon as a novel drug for treating diabetes. SGLT2 inhibitors enhance renal glucose excretion by inhibiting renal glucose reabsorption. Consequently, SGLT2 inhibitors reduce plasma glucose insulin independently and improve insulin resistance in diabetes. To date, various SGLT2 inhibitors have been developed and evaluated in clinical studies. The potency and positioning of SGLT2 inhibitors as an antidiabetic drug are dependent on their characteristic profile, which induces selectivity, efficacy, pharmacokinetics, and safety. This profile decides which SGLT2 inhibitors can be expected for application of the theoretical concept of reducing renal glucose reabsorption for the treatment of diabetes. I review the structure and advancing profile of various SGLT2 inhibitors, comparing their similarities and differences, and discuss the expected SGLT2 inhibitors for an emerging category of antidiabetic drugs.

  12. Environmental life cycle analysis of potato sprout inhibitors

    NARCIS (Netherlands)

    Kerstholt, R.P.V.; Ree, C.M.; Moll, H.C.

    Potato sprout inhibitors are generally applied to suppress sprouting during winter storage. This study presents the compared environmental profiles of the two sprout inhibitors available on the Dutch market: A traditional chemical product with isopropyl-3-chlorophenylcarbamate (CIPC) and

  13. [Inhibitors of proteolytic enzymes under abiotic stresses in plants (review)].

    Science.gov (United States)

    Mosolov, V V; Valueva, T A

    2011-01-01

    Data on the role of proteolytic enzyme inhibitors in plant adaptation to various unfavorable environmental abiotic factors--water deficiency, salinization of soil, extreme temperatures, etc.--and also probable functions of proteinases inhibitors in natural plant senescense are considered.

  14. Cellular growth kinetics distinguish a cyclophilin inhibitor from an HSP90 inhibitor as a selective inhibitor of hepatitis C virus.

    Directory of Open Access Journals (Sweden)

    Rudolf K F Beran

    Full Text Available During antiviral drug discovery, it is critical to distinguish molecules that selectively interrupt viral replication from those that reduce virus replication by adversely affecting host cell viability. In this report we investigate the selectivity of inhibitors of the host chaperone proteins cyclophilin A (CypA and heat-shock protein 90 (HSP90 which have each been reported to inhibit replication of hepatitis C virus (HCV. By comparing the toxicity of the HSP90 inhibitor, 17-(Allylamino-17-demethoxygeldanamycin (17-AAG to two known cytostatic compounds, colchicine and gemcitabine, we provide evidence that 17-AAG exerts its antiviral effects indirectly through slowing cell growth. In contrast, a cyclophilin inhibitor, cyclosporin A (CsA, exhibited selective antiviral activity without slowing cell proliferation. Furthermore, we observed that 17-AAG had little antiviral effect in a non-dividing cell-culture model of HCV replication, while CsA reduced HCV titer by more than two orders of magnitude in the same model. The assays we describe here are useful for discriminating selective antivirals from compounds that indirectly affect virus replication by reducing host cell viability or slowing cell growth.

  15. SGLT2 Inhibitors: Benefit/Risk Balance.

    Science.gov (United States)

    Scheen, André J

    2016-10-01

    Inhibitors of sodium-glucose cotransporters type 2 (SGLT2) reduce hyperglycemia by increasing urinary glucose excretion. They have been evaluated in patients with type 2 diabetes treated with diet/exercise, metformin, dual oral therapy or insulin. Three agents are available in Europe and the USA (canagliflozin, dapagliflozin, empagliflozin) and others are commercialized in Japan or in clinical development. SGLT2 inhibitors reduce glycated hemoglobin, with a minimal risk of hypoglycemia. They exert favorable effects beyond glucose control with consistent body weight, blood pressure, and serum uric acid reductions. Empagliflozin showed remarkable reductions in cardiovascular/all-cause mortality and in hospitalization for heart failure in patients with previous cardiovascular disease. Positive renal outcomes were also shown with empagliflozin. Mostly reported adverse events are genital mycotic infections, while urinary tract infections and events linked to volume depletion are rather rare. Concern about a risk of ketoacidosis and bone fractures has been recently raised, which deserves caution and further evaluation.

  16. Serine protease inhibitors of parasitic helminths.

    Science.gov (United States)

    Molehin, Adebayo J; Gobert, Geoffrey N; McManus, Donald P

    2012-05-01

    Serine protease inhibitors (serpins) are a superfamily of structurally conserved proteins that inhibit serine proteases and play key physiological roles in numerous biological systems such as blood coagulation, complement activation and inflammation. A number of serpins have now been identified in parasitic helminths with putative involvement in immune regulation and in parasite survival through interference with the host immune response. This review describes the serpins and smapins (small serine protease inhibitors) that have been identified in Ascaris spp., Brugia malayi, Ancylostoma caninum Onchocerca volvulus, Haemonchus contortus, Trichinella spiralis, Trichostrongylus vitrinus, Anisakis simplex, Trichuris suis, Schistosoma spp., Clonorchis sinensis, Paragonimus westermani and Echinococcus spp. and discusses their possible biological functions, including roles in host-parasite interplay and their evolutionary relationships.

  17. Secreted and Transmembrane Wnt Inhibitors and Activators

    Science.gov (United States)

    Cruciat, Cristina-Maria; Niehrs, Christof

    2013-01-01

    Signaling by the Wnt family of secreted glycoproteins plays important roles in embryonic development and adult homeostasis. Wnt signaling is modulated by a number of evolutionarily conserved inhibitors and activators. Wnt inhibitors belong to small protein families, including sFRP, Dkk, WIF, Wise/SOST, Cerberus, IGFBP, Shisa, Waif1, APCDD1, and Tiki1. Their common feature is to antagonize Wnt signaling by preventing ligand–receptor interactions or Wnt receptor maturation. Conversely, the Wnt activators, R-spondin and Norrin, promote Wnt signaling by binding to Wnt receptors or releasing a Wnt-inhibitory step. With few exceptions, these antagonists and agonists are not pure Wnt modulators, but also affect additional signaling pathways, such as TGF-β and FGF signaling. Here we discuss their interactions with Wnt ligands and Wnt receptors, their role in developmental processes, as well as their implication in disease. PMID:23085770

  18. Raltegravir: first in class HIV integrase inhibitor

    Directory of Open Access Journals (Sweden)

    Zelalem Temesgen

    2008-06-01

    Full Text Available Zelalem Temesgen1, Dawd S Siraj21Mayo Clinic, Rochester, MN, USA; 2East Carolina University Greenville, NC, USAAbstract: On October 16, 2007, the US Food and Drug Administration (FDA approved raltegravir for treatment of human immunodeficiency virus (HIV-1 infection in combination with other antiretroviral agents in treatment-experienced adult patients who have evidence of viral replication and HIV-1 strains resistant to multiple antiretroviral agents. Raltegravir is first in a novel class of antiretroviral drugs known as integrase inhibitors. It has demonstrated potent anti HIV activity in both antiretroviral treatment-naïve and experienced patients. The most common adverse events reported with raltegravir during phase 2 and 3 clinical trials were diarrhea, nausea, and headache. Laboratory abnormalities include mild elevations in liver transaminases and creatine phosphokinase.Keywords: raltegravir, HIV, antiretroviral agents, integrase inhibitors

  19. Small molecule inhibitors of anthrax edema factor.

    Science.gov (United States)

    Jiao, Guan-Sheng; Kim, Seongjin; Moayeri, Mahtab; Thai, April; Cregar-Hernandez, Lynne; McKasson, Linda; O'Malley, Sean; Leppla, Stephen H; Johnson, Alan T

    2018-01-15

    Anthrax is a highly lethal disease caused by the Gram-(+) bacteria Bacillus anthracis. Edema toxin (ET) is a major contributor to the pathogenesis of disease in humans exposed to B. anthracis. ET is a bipartite toxin composed of two proteins secreted by the vegetative bacteria, edema factor (EF) and protective antigen (PA). Our work towards identifying a small molecule inhibitor of anthrax edema factor is the subject of this letter. First we demonstrate that the small molecule probe 5'-Fluorosulfonylbenzoyl 5'-adenosine (FSBA) reacts irreversibly with EF and blocks enzymatic activity. We then show that the adenosine portion of FSBA can be replaced to provide more drug-like molecules which are up to 1000-fold more potent against EF relative to FSBA, display low cross reactivity when tested against a panel of kinases, and are nanomolar inhibitors of EF in a cell-based assay of cAMP production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Novel nonpeptidic inhibitors of peptide deformylase.

    Science.gov (United States)

    Jayasekera, M M; Kendall, A; Shammas, R; Dermyer, M; Tomala, M; Shapiro, M A; Holler, T P

    2000-09-15

    A novel series of nonpeptidic compounds structurally related to the known anticholesteremic thyropropic acid were found to inhibit Escherichia coli peptide deformylase (PDF), with IC50 values in the low-micromolar range. Kinetic analysis of [4-(4-hydroxyphenoxy)-3,5-diiodophenyl]acetic acid reveals competitive inhibition, with a Ki value of 0.66 +/- 0.007 microM. A structure-activity relationship study demonstrates that the carboxylate is required for activity, while the distal phenolic function can be methylated without significant effect. Either decreasing the number of iodine atoms on the molecule to one or increasing the number of iodine atoms to four results in the loss of an order of magnitude in potency. These compounds are the first nonpeptidic inhibitors disclosed and represent a template from which better inhibitors might be designed.

  1. Potent peptidic fusion inhibitors of influenza virus

    Energy Technology Data Exchange (ETDEWEB)

    Kadam, Rameshwar U.; Juraszek, Jarek; Brandenburg, Boerries; Buyck, Christophe; Schepens, Wim B. G.; Kesteleyn, Bart; Stoops, Bart; Vreeken, Rob J.; Vermond, Jan; Goutier, Wouter; Tang, Chan; Vogels, Ronald; Friesen, Robert H. E.; Goudsmit, Jaap; van Dongen, Maria J. P.; Wilson, Ian A.

    2017-09-28

    Influenza therapeutics with new targets and mechanisms of action are urgently needed to combat potential pandemics, emerging viruses, and constantly mutating strains in circulation. We report here on the design and structural characterization of potent peptidic inhibitors of influenza hemagglutinin. The peptide design was based on complementarity-determining region loops of human broadly neutralizing antibodies against the hemagglutinin (FI6v3 and CR9114). The optimized peptides exhibit nanomolar affinity and neutralization against influenza A group 1 viruses, including the 2009 H1N1 pandemic and avian H5N1 strains. The peptide inhibitors bind to the highly conserved stem epitope and block the low pH–induced conformational rearrangements associated with membrane fusion. These peptidic compounds and their advantageous biological properties should accelerate the development of new small molecule– and peptide-based therapeutics against influenza virus.

  2. Corrosion protection with eco-friendly inhibitors

    Science.gov (United States)

    Shahid, Muhammad

    2011-12-01

    Corrosion occurs as a result of the interaction of a metal with its environment. The extent of corrosion depends on the type of metal, the existing conditions in the environment and the type of aggressive ions present in the medium. For example, CO3-2 and NO-3 produce an insoluble deposit on the surface of iron, resulting in the isolation of metal and consequent decrease of corrosion. On the other hand, halide ions are adsorbed selectively on the metal surface and prevent formation of the oxide phase on the metal surface, resulting in continuous corrosion. Iron, aluminum and their alloys are widely used, both domestically and industrially. Linear alkylbenzene and linear alkylbenzene sulfonate are commonly used as detergents. They have also been found together in waste water. It is claimed that these chemicals act as inhibitors for stainless steel and aluminum. Release of toxic gases as a result of corrosion in pipelines may lead in certain cases to air pollution and possible health hazards. Therefore, there are two ways to look at the relationship between corrosion and pollution: (i) corrosion of metals and alloys due to environmental pollution and (ii) environmental pollution as a result of corrosion protection. This paper encompasses the two scenarios and possible remedies for various cases, using 'green' inhibitors obtained either from plant extracts or from pharmaceutical compounds. In the present study, the effect of piperacillin sodium as a corrosion inhibitor for mild steel was investigated using a weight-loss method as well as a three-electrode dc electrochemical technique. It was found that the corrosion rate decreased as the concentration of the inhibitor increased up to 9×10-4 M 93% efficiency was exhibited at this concentration.

  3. Acrosin inhibitor detecting along the boar epididymis

    Czech Academy of Sciences Publication Activity Database

    Maňásková-Postlerová, Pavla; Cozlová, Nina; Dorosh, Andriy; Šulc, Miroslav; Guyonet, B.; Jonáková, Věra

    2016-01-01

    Roč. 82, Jan 2016 (2016), s. 733-739 ISSN 0141-8130 R&D Projects: GA ČR(CZ) GAP503/12/1834; GA MŠk(CZ) ED1.1.00/02.0109; GA ČR GA14-05547S Institutional support: RVO:86652036 ; RVO:61388971 Keywords : Acrosin inhibitor * Boar epididymis * Spermatozoa Subject RIV: CE - Biochemistry Impact factor: 3.671, year: 2016

  4. Cyclooxygenase-2 inhibitors and knee prosthesis surgery

    OpenAIRE

    Meunier, Andreas

    2008-01-01

    Adverse effects of cyclooxygenase (COX) inhibitors on bone healing have previously been demonstrated in diaphyseal fracture models in animals. In spite of that, they are widely used as postoperative analgesics in orthopaedic surgery. After joint replacement, a bone repair process starts at the interface between bone and cement. If this process is disturbed, the prosthesis may never become rigidly fixed to the bone, leading to migration and with time loosening. This thesis investigates the eff...

  5. Aurora kinase inhibitors: Progress towards the clinic

    Czech Academy of Sciences Publication Activity Database

    Kollareddy, M.; Zheleva, D.; Dzubak, P.; Brahmkshatriya, Pathik; Lepšík, Martin; Hajduch, M.

    2012-01-01

    Roč. 30, č. 6 (2012), s. 2411-2432 ISSN 0167-6997 Grant - others:GA ČR(CZ) GA301/08/1649; GA ČR(CZ) GD303/09/H048 Program:GA; GD Institutional research plan: CEZ:AV0Z40550506 Keywords : Aurora kinases * cancer * inhibitors Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.498, year: 2012

  6. GSK-3 inhibitors induce chromosome instability

    Directory of Open Access Journals (Sweden)

    Staples Oliver D

    2007-08-01

    Full Text Available Abstract Background Several mechanisms operate during mitosis to ensure accurate chromosome segregation. However, during tumour evolution these mechanisms go awry resulting in chromosome instability. While several lines of evidence suggest that mutations in adenomatous polyposis coli (APC may promote chromosome instability, at least in colon cancer, the underlying mechanisms remain unclear. Here, we turn our attention to GSK-3 – a protein kinase, which in concert with APC, targets β-catenin for proteolysis – and ask whether GSK-3 is required for accurate chromosome segregation. Results To probe the role of GSK-3 in mitosis, we inhibited GSK-3 kinase activity in cells using a panel of small molecule inhibitors, including SB-415286, AR-A014418, 1-Azakenpaullone and CHIR99021. Analysis of synchronised HeLa cells shows that GSK-3 inhibitors do not prevent G1/S progression or cell division. They do, however, significantly delay mitotic exit, largely because inhibitor-treated cells have difficulty aligning all their chromosomes. Although bipolar spindles form and the majority of chromosomes biorient, one or more chromosomes often remain mono-oriented near the spindle poles. Despite a prolonged mitotic delay, anaphase frequently initiates without the last chromosome aligning, resulting in chromosome non-disjunction. To rule out the possibility of "off-target" effects, we also used RNA interference to selectively repress GSK-3β. Cells deficient for GSK-3β exhibit a similar chromosome alignment defect, with chromosomes clustered near the spindle poles. GSK-3β repression also results in cells accumulating micronuclei, a hallmark of chromosome missegregation. Conclusion Thus, not only do our observations indicate a role for GSK-3 in accurate chromosome segregation, but they also raise the possibility that, if used as therapeutic agents, GSK-3 inhibitors may induce unwanted side effects by inducing chromosome instability.

  7. FAITH - Fast Assembly Inhibitor Test for HIV

    Czech Academy of Sciences Publication Activity Database

    Hadravová, Romana; Rumlová, Michaela; Ruml, T.

    2015-01-01

    Roč. 486, Dec (2015), s. 78-87 ISSN 0042-6822 R&D Projects: GA ČR(CZ) GA14-15326S; GA MŠk LO1302; GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : retrovirus * HIV * assembly * assay * inhibitor Subject RIV: EE - Microbiology, Virology Impact factor: 3.200, year: 2015 http://www.sciencedirect.com/science/article/pii/S0042682215003864

  8. Monoamine oxidase inhibitors from Gentiana lutea.

    Science.gov (United States)

    Haraguchi, Hiroyuki; Tanaka, Yasumasa; Kabbash, Amal; Fujioka, Toshihiro; Ishizu, Takashi; Yagi, Akira

    2004-08-01

    Three monoamine oxidase (MAO) inhibitors were isolated from Gentiana lutea. Their structures were elucidated to be 3-3''linked-(2'-hydroxy-4-O-isoprenylchalcone)-(2'''-hydroxy-4''-O-isoprenyldihydrochalcone) (1), 2-methoxy-3-(1,1'-dimethylallyl)-6a,10a-dihydrobenzo(1,2-c)chroman-6-one and 5-hydroxyflavanone. These compounds, and the hydrolysis product of 1, displayed competitive inhibitory properties against MAO-B which was more effective than MAO-A.

  9. Trial Watch: Proteasomal inhibitors for anticancer therapy.

    Science.gov (United States)

    Obrist, Florine; Manic, Gwenola; Kroemer, Guido; Vitale, Ilio; Galluzzi, Lorenzo

    2015-01-01

    The so-called "ubiquitin-proteasome system" (UPS) is a multicomponent molecular apparatus that catalyzes the covalent attachment of several copies of the small protein ubiquitin to other proteins that are generally (but not always) destined to proteasomal degradation. This enzymatic cascade is crucial for the maintenance of intracellular protein homeostasis (both in physiological conditions and in the course of adaptive stress responses), and regulates a wide array of signaling pathways. In line with this notion, defects in the UPS have been associated with aging as well as with several pathological conditions including cardiac, neurodegenerative, and neoplastic disorders. As transformed cells often experience a constant state of stress (as a result of the hyperactivation of oncogenic signaling pathways and/or adverse microenvironmental conditions), their survival and proliferation are highly dependent on the integrity of the UPS. This rationale has driven an intense wave of preclinical and clinical investigation culminating in 2003 with the approval of the proteasomal inhibitor bortezomib by the US Food and Drug Administration for use in multiple myeloma patients. Another proteasomal inhibitor, carfilzomib, is now licensed by international regulatory agencies for use in multiple myeloma patients, and the approved indications for bortezomib have been extended to mantle cell lymphoma. This said, the clinical activity of bortezomib and carfilzomib is often limited by off-target effects, innate/acquired resistance, and the absence of validated predictive biomarkers. Moreover, the antineoplastic activity of proteasome inhibitors against solid tumors is poor. In this Trial Watch we discuss the contribution of the UPS to oncogenesis and tumor progression and summarize the design and/or results of recent clinical studies evaluating the therapeutic profile of proteasome inhibitors in cancer patients.

  10. Adverse Effects of COX-2 Inhibitors

    Directory of Open Access Journals (Sweden)

    Jagdish N. Sharma

    2005-01-01

    Full Text Available Cyclooxygenase-2 selective inhibitors (COXIBs were developed with the prime object of minimizing gastrointestinal adverse effects, which are seen with the use of traditional nonsteroidal anti-inflammatory drugs (NSAIDs. Their long-term use is limited by the development of hypertension, edema, and congestive heart failure in a significant proportion of patients. NSAIDs block the activity of both COX isozymes, COX-1 and COX-2, which mediate the enzymatic conversion of arachidonate to prostaglandin H2 (PGH2 and other prostaglandin (PG metabolites. It is well established that the cardiovascular profile of COX-2 inhibitors can be accounted for by inhibition of COX-dependent PG synthesis. Following the COX-mediated synthesis of PGH2 from arachidonate, PGH2 is metabolized to one of at least five bioactive PGs, including PGE2, PGI2, PGF2, PGD2, or thromboxane A2 (TXA2. These prostanoids have pleiotropic cardiovascular effects, altering platelet function and renal function, and they are acting either as vasodilators or vasoconstrictors. Although COX-1 and COX-2 exhibit similar biochemical activity in converting arachidonate to PGH2in vitro, the ultimate prostanoids they produce in vivo may be different due to differential regulation of COX-1 and COX-2, tissue distribution, and availability of the prostanoid synthases. PGs have been established as being critically involved in mitigating hypertension, helping to maintain medullary blood flow (MBF, promoting urinary salt excretion, and preserving the normal homeostasis of thrombosis, and the researchers found that the use of COX-2 inhibitors caused many serious complications in altering the normal body homeostasis. The purpose of the present research is to explain briefly the side effects of COX-2 inhibitors on the renal and cardiovascular system.

  11. Rust Inhibitor And Fungicide For Cooling Systems

    Science.gov (United States)

    Adams, James F.; Greer, D. Clay

    1988-01-01

    Mixture of benzotriazole, benzoic acid, and fungicide prevents growth of rust and fungus. Water-based cooling mixture made from readily available materials prevents formation of metallic oxides and growth of fungi in metallic pipes. Coolant remains clear and does not develop thick sludge tending to collect in low points in cooling systems with many commercial rust inhibitors. Coolant compatible with iron, copper, aluminum, and stainless steel. Cannot be used with cadmium or cadmium-plated pipes.

  12. Luminometric method for screening retroviral protease inhibitors

    Czech Academy of Sciences Publication Activity Database

    Horáková, D.; Rumlová, Michaela; Pichová, Iva; Ruml, Tomáš

    2005-01-01

    Roč. 345, č. 1 (2005), s. 96-101 ISSN 0003-2697 R&D Projects: GA AV ČR(CZ) IAA4055304; GA MŠk(CZ) 1M0508; GA MŠk(CZ) 1M0520 Institutional research plan: CEZ:AV0Z40550506 Keywords : retroviral protease * inhibitors * luminescent assay Subject RIV: CE - Biochemistry Impact factor: 2.670, year: 2005

  13. Serine proteinases and their inhibitors in fertilization

    Czech Academy of Sciences Publication Activity Database

    Jonáková, Věra

    2000-01-01

    Roč. 3, 3,4 (2000), s. 23 [ Proteolytic enzymes and their inhibitors in physiology and pathogenesis. 14.09.2000, Plzen] R&D Projects: GA ČR GV524/96/K162; GA ČR GA303/99/0357; GA MŠk VS96141 Grant - others:GA UK(CZ) 12/1998 Institutional research plan: CEZ:AV0Z5052915 Subject RIV: EB - Genetics ; Molecular Biology

  14. Modelling of potentially promising SARS protease inhibitors

    International Nuclear Information System (INIS)

    Plewczynski, Dariusz; Hoffmann, Marcin; Grotthuss, Marcin von; Knizewski, Lukasz; Rychewski, Leszek; Eitner, Krystian; Ginalski, Krzysztof

    2007-01-01

    In many cases, at the beginning of a high throughput screening experiment some information about active molecules is already available. Active compounds (such as substrate analogues, natural products and inhibitors of related proteins) are often identified in low throughput validation studies on a biochemical target. Sometimes the additional structural information is also available from crystallographic studies on protein and ligand complexes. In addition, the structural or sequence similarity of various protein targets yields a novel possibility for drug discovery. Co-crystallized compounds from homologous proteins can be used to design leads for a new target without co-crystallized ligands. In this paper we evaluate how far such an approach can be used in a real drug campaign, with severe acute respiratory syndrome (SARS) coronavirus providing an example. Our method is able to construct small molecules as plausible inhibitors solely on the basis of the set of ligands from crystallized complexes of a protein target, and other proteins from its structurally homologous family. The accuracy and sensitivity of the method are estimated here by the subsequent use of an electronic high throughput screening flexible docking algorithm. The best performing ligands are then used for a very restrictive similarity search for potential inhibitors of the SARS protease within the million compounds from the Ligand.Info small molecule meta-database. The selected molecules can be passed on for further experimental validation

  15. Inhibitors of polyamine metabolism: review article.

    Science.gov (United States)

    Wallace, H M; Fraser, A V

    2004-07-01

    The identification of increased polyamine concentrations in a variety of diseases from cancer and psoriasis to parasitic infections has led to the hypothesis that manipulation of polyamine metabolism is a realistic target for therapeutic or preventative intervention in the treatment of certain diseases. The early development of polyamine biosynthetic single enzyme inhibitors such as alpha-difluoromethylornithine (DFMO) and methylglyoxal bis(guanylhydrazone) showed some interesting early promise as anticancer drugs, but ultimately failed in vivo. Despite this, DFMO is currently in use as an effective anti-parasitic agent and has recently also been shown to have further potential as a chemopreventative agent in colorectal cancer. The initial promise in vitro led to the development and testing of other potential inhibitors of the pathway namely the polyamine analogues. The analogues have met with greater success than the single enzyme inhibitors possibly due to their multiple targets. These include down regulation of polyamine biosynthesis through inhibition of ornithine decarboxylase and S-adenosylmethionine decarboxylase and decreased polyamine uptake. This coupled with increased activity of the catabolic enzymes, polyamine oxidase and spermidine/spermine N1-acetyltransferase, and increased polyamine export has made the analogues more effective in depleting polyamine pools. Recently, the identification of a new oxidase (PAO-h1/SMO) in polyamine catabolism and evidence of induction of both PAO and PAO-h1/SMO in response to polyamine analogue treatment, suggests the analogues may become an important part of future chemotherapeutic and/or chemopreventative regimens.

  16. Recent advances in botulinum neurotoxin inhibitor development.

    Science.gov (United States)

    Kiris, Erkan; Burnett, James C; Kane, Christopher D; Bavari, Sina

    2014-01-01

    Botulinum neurotoxins (BoNTs) are endopeptidases that target motor neurons and block acetylcholine neurotransmitter release. This action results in the muscle paralysis that defines the disease botulism. To date, there are no FDA-approved therapeutics to treat BoNT-mediated paralysis after intoxication of the motor neuron. Importantly, the rationale for pursuing treatments to counter these toxins is driven by their potential misuse. Current drug discovery efforts have mainly focused on small molecules, peptides, and peptidomimetics that can directly and competitively inhibit BoNT light chain proteolytic activity. Although this is a rational approach, direct inhibition of the Zn(2+) metalloprotease activity has been elusive as demonstrated by the dearth of candidates undergoing clinical evaluation. Therefore, broadening the scope of viable targets beyond that of active site protease inhibitors represents an additional strategy that could move the field closer to the clinic. Here we review the rationale, and discuss the outcomes of earlier approaches and highlight potential new targets for BoNT inhibition. These include BoNT uptake and processing inhibitors, enzymatic inhibitors, and modulators of neuronal processes associated with toxin clearance, neurotransmitter potentiation, and other pathways geared towards neuronal recovery and repair.

  17. A porphodimethene chemical inhibitor of uroporphyrinogen decarboxylase.

    Directory of Open Access Journals (Sweden)

    Kenneth W Yip

    Full Text Available Uroporphyrinogen decarboxylase (UROD catalyzes the conversion of uroporphyrinogen to coproporphyrinogen during heme biosynthesis. This enzyme was recently identified as a potential anticancer target; its inhibition leads to an increase in reactive oxygen species, likely mediated by the Fenton reaction, thereby decreasing cancer cell viability and working in cooperation with radiation and/or cisplatin. Because there is no known chemical UROD inhibitor suitable for use in translational studies, we aimed to design, synthesize, and characterize such a compound. Initial in silico-based design and docking analyses identified a potential porphyrin analogue that was subsequently synthesized. This species, a porphodimethene (named PI-16, was found to inhibit UROD in an enzymatic assay (IC50 = 9.9 µM, but did not affect porphobilinogen deaminase (at 62.5 µM, thereby exhibiting specificity. In cellular assays, PI-16 reduced the viability of FaDu and ME-180 cancer cells with half maximal effective concentrations of 22.7 µM and 26.9 µM, respectively, and only minimally affected normal oral epithelial (NOE cells. PI-16 also combined effectively with radiation and cisplatin, with potent synergy being observed in the case of cisplatin in FaDu cells (Chou-Talalay combination index <1. This work presents the first known synthetic UROD inhibitor, and sets the foundation for the design, synthesis, and characterization of higher affinity and more effective UROD inhibitors.

  18. Emicizumab Prophylaxis in Hemophilia A with Inhibitors.

    Science.gov (United States)

    Oldenburg, Johannes; Mahlangu, Johnny N; Kim, Benjamin; Schmitt, Christophe; Callaghan, Michael U; Young, Guy; Santagostino, Elena; Kruse-Jarres, Rebecca; Negrier, Claude; Kessler, Craig; Valente, Nancy; Asikanius, Elina; Levy, Gallia G; Windyga, Jerzy; Shima, Midori

    2017-08-31

    Emicizumab (ACE910) bridges activated factor IX and factor X to restore the function of activated factor VIII, which is deficient in persons with hemophilia A. This phase 3, multicenter trial assessed once-weekly subcutaneous emicizumab prophylaxis in persons with hemophilia A with factor VIII inhibitors. We enrolled participants who were 12 years of age or older. Those who had previously received episodic treatment with bypassing agents were randomly assigned in a 2:1 ratio to emicizumab prophylaxis (group A) or no prophylaxis (group B). The primary end point was the difference in bleeding rates between group A and group B. Participants who had previously received prophylactic treatment with bypassing agents received emicizumab prophylaxis in group C. A total of 109 male participants with hemophilia A with inhibitors were enrolled. The annualized bleeding rate was 2.9 events (95% confidence interval [CI], 1.7 to 5.0) among participants who were randomly assigned to emicizumab prophylaxis (group A, 35 participants) versus 23.3 events (95% CI, 12.3 to 43.9) among those assigned to no prophylaxis (group B, 18 participants), representing a significant difference of 87% in favor of emicizumab prophylaxis (Phemophilia A with inhibitors. (Funded by F. Hoffmann-La Roche and Chugai Pharmaceutical; HAVEN 1 ClinicalTrials.gov number, NCT02622321 .).

  19. Modelling of potentially promising SARS protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Plewczynski, Dariusz [Interdisciplinary Centre for Mathematical and Computational Modelling, ICM, Warsaw University, Pawinskiego 5a Street, 02-106 Warsaw (Poland); Hoffmann, Marcin [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Grotthuss, Marcin von [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Knizewski, Lukasz [Interdisciplinary Centre for Mathematical and Computational Modelling, ICM, Warsaw University, Pawinskiego 5a Street, 02-106 Warsaw (Poland); Rychewski, Leszek [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Eitner, Krystian [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Ginalski, Krzysztof [Interdisciplinary Centre for Mathematical and Computational Modelling, ICM, Warsaw University, Pawinskiego 5a Street, 02-106 Warsaw (Poland)

    2007-07-18

    In many cases, at the beginning of a high throughput screening experiment some information about active molecules is already available. Active compounds (such as substrate analogues, natural products and inhibitors of related proteins) are often identified in low throughput validation studies on a biochemical target. Sometimes the additional structural information is also available from crystallographic studies on protein and ligand complexes. In addition, the structural or sequence similarity of various protein targets yields a novel possibility for drug discovery. Co-crystallized compounds from homologous proteins can be used to design leads for a new target without co-crystallized ligands. In this paper we evaluate how far such an approach can be used in a real drug campaign, with severe acute respiratory syndrome (SARS) coronavirus providing an example. Our method is able to construct small molecules as plausible inhibitors solely on the basis of the set of ligands from crystallized complexes of a protein target, and other proteins from its structurally homologous family. The accuracy and sensitivity of the method are estimated here by the subsequent use of an electronic high throughput screening flexible docking algorithm. The best performing ligands are then used for a very restrictive similarity search for potential inhibitors of the SARS protease within the million compounds from the Ligand.Info small molecule meta-database. The selected molecules can be passed on for further experimental validation.

  20. Structure-Based Search for New Inhibitors of Cholinesterases

    Directory of Open Access Journals (Sweden)

    Barbara Malawska

    2013-03-01

    Full Text Available Cholinesterases are important biological targets responsible for regulation of cholinergic transmission, and their inhibitors are used for the treatment of Alzheimer’s disease. To design new cholinesterase inhibitors, of different structure-based design strategies was followed, including the modification of compounds from a previously developed library and a fragment-based design approach. This led to the selection of heterodimeric structures as potential inhibitors. Synthesis and biological evaluation of selected candidates confirmed that the designed compounds were acetylcholinesterase inhibitors with IC50 values in the mid-nanomolar to low micromolar range, and some of them were also butyrylcholinesterase inhibitors.

  1. ELISA analysis of soybean trypsin inhibitors in processed foods.

    Science.gov (United States)

    Brandon, D L; Bates, A H; Friedman, M

    1991-01-01

    Soybean proteins are widely used in human foods in a variety of forms, including infant formulas, flour, protein concentrates, protein isolates, soy sauces, textured soy fibers, and tofu. The presence of inhibitors of digestive enzymes in soy proteins impairs the nutritional quality and possibly the safety of soybeans and other legumes. Processing, based on the use of heat or fractionation of protein isolates, does not completely inactivate or remove these inhibitors, so that residual amounts of inhibitors are consumed by animals and humans. New monoclonal antibody-based immunoassays can measure low levels of the soybean Kunitz trypsin inhibitor (KTI) and the Bowman-Birk trypsin and chymotrypsin inhibitor (BBI) and the Bowman-Birk foods. The enzyme-linked immunosorbent assay (ELISA) was used to measure the inhibitor content of soy concentrates, isolates, and flours, both heated and unheated; a commercial soy infant formula; KTI and BBI with rearranged disulfide bonds; browning products derived from heat-treatment of KTI with glucose and starch; and KTI exposed to high pH. The results indicate that even low inhibitor isolates contain significant amounts of specific inhibitors. Thus, infants on soy formula consume about 10 mg of KTI plus BBI per day. The immunoassays complement the established enzymatic assays of trypsin and chymotrypsin inhibitors, and have advantages in (a) measuring low levels of inhibitors in processed foods; and (b) differentiating between the Kunitz and Bowman-Birk inhibitors. The significance of our findings for food safety are discussed.

  2. Tyrosine kinase inhibitors: Multi-targeted or single-targeted?

    Science.gov (United States)

    Broekman, Fleur; Giovannetti, Elisa; Peters, Godefridus J

    2011-02-10

    Since in most tumors multiple signaling pathways are involved, many of the inhibitors in clinical development are designed to affect a wide range of targeted kinases. The most important tyrosine kinase families in the development of tyrosine kinase inhibitors are the ABL, SCR, platelet derived growth factor, vascular endothelial growth factor receptor and epidermal growth factor receptor families. Both multi-kinase inhibitors and single-kinase inhibitors have advantages and disadvantages, which are related to potential resistance mechanisms, pharmacokinetics, selectivity and tumor environment. In different malignancies various tyrosine kinases are mutated or overexpressed and several resistance mechanisms exist. Pharmacokinetics is influenced by interindividual differences and differs for two single targeted inhibitors or between patients treated by the same tyrosine kinase inhibitor. Different tyrosine kinase inhibitors have various mechanisms to achieve selectivity, while differences in gene expression exist between tumor and stromal cells. Considering these aspects, one type of inhibitor can generally not be preferred above the other, but will depend on the specific genetic constitution of the patient and the tumor, allowing personalized therapy. The most effective way of cancer treatment by using tyrosine kinase inhibitors is to consider each patient/tumor individually and to determine the strategy that specifically targets the consequences of altered (epi)genetics of the tumor. This strategy might result in treatment by a single multi kinase inhibitor for one patient, but in treatment by a couple of single kinase inhibitors for other patients.

  3. Evaluation of Encapsulated Inhibitor for Autonomous Corrosion Protection

    Science.gov (United States)

    Johnsey, M. N.; Li, W.; Buhrow, J. W.; Calle, L. M.; Pearman, B. P.; Zhang, X.

    2015-01-01

    This work concerns the development of smart coating technologies based on microencapsulation for the autonomous control of corrosion. Microencapsulation allows the incorporation of corrosion inhibitors into coating which provides protection through corrosion-controlled release of these inhibitors.One critical aspect of a corrosion protective smart coating is the selection of corrosion inhibitor for encapsulation and comparison of the inhibitor function before and after encapsulation. For this purpose, a systematic approach is being used to evaluate free and encapsulated corrosion inhibitors by salt immersion. Visual, optical microscope, and Scanning Electron Microscope (with low-angle backscatter electron detector) are used to evaluate these inhibitors. It has been found that the combination of different characterization tools provide an effective method for evaluation of early stage localized corrosion and the effectiveness of corrosion inhibitors.

  4. The "SWOT" of BRAF inhibition in melanoma: RAF inhibitors, MEK inhibitors or both?

    Science.gov (United States)

    Nissan, Moriah H; Solit, David B

    2011-12-01

    Activating mutations in the BRAF gene are among the most prevalent kinase mutations in human cancer. BRAF mutations are most frequent in patients with melanoma where they occur in approximately 50% of patients with advanced disease. Remarkable clinical activity has recently been reported with highly selective RAF inhibitors in melanoma patients whose tumors harbor V600E BRAF mutations. The response rates of RAF inhibitors in patients with BRAF-mutant melanomas far exceed the activity level of any prior therapy studied in this disease. The results suggest that we have entered an era of personalized therapy for patients with metastatic melanoma in which treatment selection will be guided by BRAF mutational status. This review will discuss the strengths, weaknesses, opportunities and threats ("SWOT") of developing RAF and MEK selective inhibitors as anti-cancer therapies, recent insights into the mechanisms of intrinsic and acquired resistance to these agents, and current efforts to develop mechanism-based combination therapies.

  5. F8 haplotype and inhibitor risk: results from the Hemophilia Inhibitor Genetics Study (HIGS) Combined Cohort

    Science.gov (United States)

    Schwarz, John; Astermark, Jan; Menius, Erika D.; Carrington, Mary; Donfield, Sharyne M.; Gomperts, Edward D.; Nelson, George W.; Oldenburg, Johannes; Pavlova, Anna; Shapiro, Amy D.; Winkler, Cheryl A.; Berntorp, Erik

    2012-01-01

    Background Ancestral background, specifically African descent, confers higher risk for development of inhibitory antibodies to factor VIII (FVIII) in hemophilia A. It has been suggested that differences in the distribution of factor VIII gene (F8) haplotypes, and mismatch between endogenous F8 haplotypes and those comprising products used for treatment could contribute to risk. Design and Methods Data from the HIGS Combined Cohort were used to determine the association between F8 haplotype 3 (H3) vs. haplotypes 1 and 2 (H1+H2) and inhibitor risk among individuals of genetically-determined African descent. Other variables known to affect inhibitor risk including type of F8 mutation and HLA were included in the analysis. A second research question regarding risk related to mismatch in endogenous F8 haplotype and recombinant FVIII products used for treatment was addressed. Results H3 was associated with higher inhibitor risk among those genetically-identified (N=49) as of African ancestry, but the association did not remain significant after adjustment for F8 mutation type and the HLA variables. Among subjects of all racial ancestries enrolled in HIGS who reported early use of recombinant products (N=223), mismatch in endogenous haplotype and the FVIII proteins constituting the products used did not confer greater risk for inhibitor development. Conclusion H3 was not an independent predictor of inhibitor risk. Further, our findings did not support a higher risk of inhibitors in the presence of a haplotype mismatch between the FVIII molecule infused and that of the individual. PMID:22958194

  6. Sifuvirtide, a potent HIV fusion inhibitor peptide

    International Nuclear Information System (INIS)

    Wang, Rui-Rui; Yang, Liu-Meng; Wang, Yun-Hua; Pang, Wei; Tam, Siu-Cheung; Tien, Po; Zheng, Yong-Tang

    2009-01-01

    Enfuvirtide (ENF) is currently the only FDA approved HIV fusion inhibitor in clinical use. Searching for more drugs in this category with higher efficacy and lower toxicity seems to be a logical next step. In line with this objective, a synthetic peptide with 36 amino acid residues, called Sifuvirtide (SFT), was designed based on the crystal structure of gp41. In this study, we show that SFT is a potent anti-HIV agent with relatively low cytotoxicity. SFT was found to inhibit replication of all tested HIV strains. The effective concentrations that inhibited 50% viral replication (EC 50 ), as determined in all tested strains, were either comparable or lower than benchmark values derived from well-known anti-HIV drugs like ENF or AZT, while the cytotoxic concentrations causing 50% cell death (CC 50 ) were relatively high, rendering it an ideal anti-HIV agent. A GST-pull down assay was performed to confirm that SFT is a fusion inhibitor. Furthermore, the activity of SFT on other targets in the HIV life cycle was also investigated, and all assays showed negative results. To further understand the mechanism of action of HIV peptide inhibitors, resistant variants of HIV-1 IIIB were derived by serial virus passage in the presence of increasing doses of SFT or ENF. The results showed that there was cross-resistance between SFT and ENF. In conclusion, SFT is an ideal anti-HIV agent with high potency and low cytotoxicity, but may exhibit a certain extent of cross-resistance with ENF.

  7. [Cholinesterase inhibitors for treating dementia. Review].

    Science.gov (United States)

    Kremer, Janus

    2010-01-01

    Alzheimer's disease is the most common form of dementia seen in the clinical practice. The principal risk factor is aging. There is not currently any available curative medication. However, there a family of drugs call the cholinesterase inhibitors (donepezile, galantamine and rivastigmine) the enhances cholinergic activity in the CNS. Also, memantine is available is a NMDA receptor modulator. A new transdermal way of administration is available now for rivastigmine. The rivastigmines patches are now a rational alternative focusing in getting more tolerance, better blood levels of the drug and compliance to treatment in Alzheimer's disease patients.

  8. Serine proteinases and their inhibitors in fertilization

    Czech Academy of Sciences Publication Activity Database

    Jonáková, Věra; Jelínková-Slavíčková, Petra

    2004-01-01

    Roč. 8, 3,4 (2004), s. 108-110 ISSN 1211-8869. [Central European Conference on Human Tumor Markers /5./. Praha, 01.10.2004-03.10.2004] R&D Projects: GA ČR GA303/02/0433; GA ČR GP303/02/P069; GA ČR GP303/04/P070; GA MZd NJ7463 Institutional research plan: CEZ:AV0Z5052915 Keywords : serine proteinase * proteinase inhibitors * fertilization Subject RIV: CE - Biochemistry

  9. A New Urease Inhibitor from Viola betonicifolia

    Directory of Open Access Journals (Sweden)

    Naveed Muhammad

    2014-10-01

    Full Text Available Urease has attracted much attention, as it is directly involved in the formation of infection stones and contributes to the pathogenesis of urolithiasis, pyelonephritis, ammonia and hepatic encephalopathy, hepatic coma and urinary catheter encrustation. Moreover, urease is the major cause of pathologies induced by H. pylori, such as gastritis and peptic ulcer. In the present work, the new natural compound, 3-methoxydalbergione, was isolated from Viola betonicifolia. A mechanistic study of this compound as a natural urease inhibitor was performed by using enzyme kinetics and docking studies. 3-Methoxydalbergione could be considered as a lead molecule for drugs useful in the urease associated diseases.

  10. Tetomilast: new promise for phosphodiesterase-4 inhibitors?

    Science.gov (United States)

    Bickston, Stephen J; Snider, Kenneth R; Kappus, Matthew R

    2012-12-01

    Tetomilast is a novel thiazole phosphodiesterase-4 (PDE-4) inhibitor, which may prove useful in both the treatment of inflammatory bowel disease (IBD) and chronic obstructive pulmonary disease (COPD). Here, the authors review the pharmacology of the drug, and offer critical review of the available data for use of tetomilast in the treatment of IBD. Peer-reviewed publications, including Phase I and II clinical trials, all other formats included. Tetomilast may be beneficial in IBD. Small differences in molecules and in recombinant proteins can translate into substantial differences in clinical effects and toxicity in IBD. This is a reasonable approach when exploring new options like tetomilast.

  11. Potential mechanisms of resistance to microtubule inhibitors.

    Science.gov (United States)

    Kavallaris, Maria; Annereau, Jean-Philippe; Barret, Jean-Marc

    2008-06-01

    Antimitotic drugs targeting the microtubules, such as the taxanes and vinca alkaloids, are widely used in the treatment of neoplastic diseases. Development of drug resistance over time, however, limits the efficacy of these agents and poses a clinical challenge to long-term improvement of patient outcomes. Understanding the mechanism(s) of drug resistance becomes paramount to allowing for alternative, if not improved, therapeutic options that might circumvent this challenge. Vinflunine, a novel microtubule inhibitor, has shown superior preclinical antitumor activity, and displays a different pattern of resistance, compared with other agents in the vinca alkaloid class.

  12. Larvicides and acetylcholinesterase inhibitors from Kalanchoe species

    International Nuclear Information System (INIS)

    Trevisan, Maria Teresa Salles; Bezerra, Maria Zeneide Barbosa; Santiago, Gilvandete Maria Pinheiro; Feitosa, Chistiane Mendes; Verpoorte, Robert; Gorlaeus Laboratories, Leiden; Braz Filho, Raimundo

    2006-01-01

    Acetylcholine esterase inhibitors are successfully used to treat the symptoms of Alzheimer's disease. Extracts of three Kalanchoe species (K. brasiliensis, K. pinnata and K. gastonis-bornieri) showed acetylcholine esterase inhibitory effects and a toxic effect on Aedes aegypti larvae. Here we describe the bioassay guided fractionation of extracts of the most active extracts (K. brasiliensis) which resulted in the isolation of an active mixture of three flavonoids: 8-methoxyquercetin, 3,7-di-O-rhamnopyranoside and 8-methoxykaempferol-3,7-di-O-rhamnopyranoside. On TLC these flavonoids showed an acetylcholine esterase inhibitory effect. (author)

  13. Hepatitis C Virus NS3 Inhibitors: Current and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Kazi Abdus Salam

    2013-01-01

    Full Text Available Currently, hepatitis C virus (HCV infection is considered a serious health-care problem all over the world. A good number of direct-acting antivirals (DAAs against HCV infection are in clinical progress including NS3-4A protease inhibitors, RNA-dependent RNA polymerase inhibitors, and NS5A inhibitors as well as host targeted inhibitors. Two NS3-4A protease inhibitors (telaprevir and boceprevir have been recently approved for the treatment of hepatitis C in combination with standard of care (pegylated interferon plus ribavirin. The new therapy has significantly improved sustained virologic response (SVR; however, the adverse effects associated with this therapy are still the main concern. In addition to the emergence of viral resistance, other targets must be continually developed. One such underdeveloped target is the helicase portion of the HCV NS3 protein. This review article summarizes our current understanding of HCV treatment, particularly with those of NS3 inhibitors.

  14. Impaired fibrinolysis in the pathogenesis of dengue hemorrhagic fever.

    NARCIS (Netherlands)

    Gorp, E. van; Setiati, T.E.; Mairuhu, A.T.; Suharti, C.; Cate, H.H.; Dolmans, W.M.V.; Meer, J.W.M. van der; Hack, C.E.; Brandjes, D.P.

    2002-01-01

    The mechanisms contributing to bleeding complications in dengue hemorrhagic fever were studied by investigating the pattern of activation of the coagulation and fibrinolytic systems in 50 children with severe dengue hemorrhagic fever. Thirteen patients (26%) died, and activation of coagulation was

  15. Impaired fibrinolysis in the pathogenesis of dengue hemorrhagic fever

    NARCIS (Netherlands)

    van Gorp, Eric C. M.; Setiati, Tatty E.; Mairuhu, Albert T. A.; Suharti, Catharina; Cate Ht, Hugo ten; Dolmans, Wil M. V.; van der Meer, Jos W. M.; Hack, C. Erik; Brandjes, Dees P. M.

    2002-01-01

    The mechanisms contributing to bleeding complications in dengue hemorrhagic fever were studied by investigating the pattern of activation of the coagulation and fibrinolytic systems in 50 children with severe dengue hemorrhagic fever. Thirteen patients (26%) died, and activation of coagulation was

  16. Fibrinolysis and anticoagulant potential of a metallo protease ...

    Indian Academy of Sciences (India)

    In this study, a potent fibrinolytic enzyme-producing bacterium was isolated .... Time courses of growth and enzyme production in a culture of B. subtilis K42: ..... on a large scale in industry,would make thisoperation rapid .... Process. Biochem. 41 1545–1552. Wang SL, Kao TY, Wang CL, Yen YH, Chern MK and Chen YH.

  17. Effects of early angioplasty after fibrinolysis on prognosis of patients ...

    African Journals Online (AJOL)

    ELO

    2011-11-09

    Nov 9, 2011 ... of coronary stenting and contemporary pharmacotherapy, have been more encouraging but have not been adequately powered to definitively establish the safety and efficacy of this approach (Armstrong, 2007). We therefore performed a large, randomized trial to compare a strategy of routine transfer and ...

  18. Cerebral venous thrombosis: treatment with local fibrinolysis plus alteplase

    International Nuclear Information System (INIS)

    Asis Bravo, F. de; Delgado, F.; Cano, A.; Bautista, D.

    2002-01-01

    Cerebral venous thrombosis is a rare entity with widely variable clinical signs: thus, a high degree of suspicion is required for diagnosis. It affects the dural sinuses and may or may not invade cerebral veins. The diagnosis has usually been based on an angiographic study although, at the present time, new noninvasive imaging techniques, such as computed tomography, magnetic resonance and magnetic resonance angiography are being employed in a growing number of cases. Treatment should involve symptomatic and etiologic therapy. Although anti coagulation would appear to be a reasonable option in these patients, it remains controversial. As in other processes such as pulmonary embolism and coronary thrombosis, the introduction of novel and increasingly safe fibrinolytic drugs, together with technical innovations in the field of interventional neuroradiology, is changing the perspectives for the management of these patients. We present the case of a 43-year-old woman with right sinus thrombosis who was treated with local thrombolysis plus alteplase (tissue plasminogen activator). The authors describe the technique employed and review the literature. (Author) 16 refs

  19. A possible casual relationship between defective fibrinolysis and pulmonary hypertension

    International Nuclear Information System (INIS)

    Franz, R.C.; Ziady, F.; Hugo, N.

    1979-01-01

    Pulmonary hypertension may be associated with multiple thrombi in the pulmonary arteries or with diffuse microembolization from a cryptic source. A 27-year-old man without any of the recognized clinical risk factors for venous thrombo-embolic disease presented with repeated attacks of chest pain and dyspnoea. Haemodynamic studies were compatible with the diagnosis of primary pulmonary hypertension. Despite intensive study there was no evidence of peripheral venous thrombosis. A 125 I isotope study was done. Plasma fibrinolytic profile showed unequivocal evidence of low spontaneous plasma fibrinolytic activity. The plasminogen activator activity of the venous wall was also markedly reduced. From these findings it would seem that a defective fibrinolytic defence mechanism may be an important predisposing factor in the pathogenesis of 'primary' pulmonary hypertension

  20. Intravascular trans-catheter fibrinolysis in acute arterial obstructions

    International Nuclear Information System (INIS)

    Roversi, R.; Rossi, C.; Ricci, S.; Gemelli, G.; Ciliberti, M.A.

    1987-01-01

    The author's experiences is reported on intravascular fibrinolytic therapy with urokinase in acute arterial obstructions. Thirty-eight patients were treated, from 1983 to 1986, for acute thrombosis and/or thromboembolization, 22 of which developed on an atherosclerotic lesion, and 10 on a surgical stenotic by-pass graft. A complete vascular recanalization has been obtained, at the end of the procedure, in 69,4% of the cases, 77,7% had a definite final clinical improvement. The results correspond to the medium statistical of the various casistics analyzed for comparison. Surgery has been performed on 27,7% of the patients. Complication have been observed in 8% of the cases. IAF technique is of greatest value in the treatment of those lesions; better results have been obtained with intra-thrombus injection of the drug (as emphasized by many authors) in association with PTA and surgery. A close cooperation between interventional radiology, vascular surgery and angiology is therefore necessary in this field

  1. Coagulation and fibrinolysis in hyperparathyroidism secondary to vitamin D deficiency

    NARCIS (Netherlands)

    Elbers, Laura P. B.; Wijnberge, Marije; Meijers, Joost C. M.; Poland, Dennis C. W.; Brandjes, Dees P. M.; Fliers, Eric; Gerdes, Victor E. A.

    2018-01-01

    Abnormal coagulation tests have been observed in patients with primary hyperparathyroidism (HPT) suggesting a prothrombotic effect of parathyroid hormone (PTH). Vitamin D deficiency (VIDD) is the most frequent cause of secondary HPT. Aim of our study was to investigate the influence of HPT secondary

  2. HTCC: Broad Range Inhibitor of Coronavirus Entry.

    Directory of Open Access Journals (Sweden)

    Aleksandra Milewska

    Full Text Available To date, six human coronaviruses have been known, all of which are associated with respiratory infections in humans. With the exception of the highly pathogenic SARS and MERS coronaviruses, human coronaviruses (HCoV-NL63, HCoV-OC43, HCoV-229E, and HCoV-HKU1 circulate worldwide and typically cause the common cold. In most cases, infection with these viruses does not lead to severe disease, although acute infections in infants, the elderly, and immunocompromised patients may progress to severe disease requiring hospitalization. Importantly, no drugs against human coronaviruses exist, and only supportive therapy is available. Previously, we proposed the cationically modified chitosan, N-(2-hydroxypropyl-3-trimethylammonium chitosan chloride (HTCC, and its hydrophobically-modified derivative (HM-HTCC as potent inhibitors of the coronavirus HCoV-NL63. Here, we show that HTCC inhibits interaction of a virus with its receptor and thus blocks the entry. Further, we demonstrate that HTCC polymers with different degrees of substitution act as effective inhibitors of all low-pathogenic human coronaviruses.

  3. Lonafarnib is a potential inhibitor for neovascularization.

    Directory of Open Access Journals (Sweden)

    Linlin Sun

    Full Text Available Atherosclerosis is a common cardiovascular disease that involves the build-up of plaque on the inner walls of the arteries. Intraplaque neovacularization has been shown to be essential in the pathogenesis of atherosclerosis. Previous studies showed that small-molecule compounds targeting farnesyl transferase have the ability to prevent atherosclerosis in apolipoprotein E-deficient mice, but the underlying mechanism remains to be elucidated. In this study, we found that lonafarnib, a specific inhibitor of farnesyl transferase, elicits inhibitory effect on vascular endothelial capillary assembly in vitro in a dose-dependent manner. In addition, we showed that lonafarnib treatment led to a dose-dependent decrease in scratch wound closure in vitro, whereas it had little effect on endothelial cell proliferation. These data indicate that lonafarnib inhibits neovascularization via directly targeting endothelial cells and disturbing their motility. Moreover, we demonstrated that pharmacological inhibition of farnesyl transferase by lonafarnib significantly impaired centrosome reorientation toward the leading edge of endothelial cells. Mechanistically, we found that the catalytic β subunit of farnesyl transferase associated with a cytoskeletal protein important for the establishment and maintenance of cell polarity. Additionally, we showed that lonafarnib remarkably inhibited the expression of the cytoskeletal protein and interrupted its interaction with farnesyl transferase. Our findings thus offer novel mechanistic insight into the protective effect of farnesyl transferase inhibitors on atherosclerosis and provide encouraging evidence for the potential use of this group of agents in inhibiting plaque neovascularization.

  4. Proton Pump Inhibitors and Risk of Rhabdomyolysis.

    Science.gov (United States)

    Duncan, Scott J; Howden, Colin W

    2017-01-01

    Proton pump inhibitors (PPIs) have been associated with a variety of adverse events, although the level of evidence for many of these is weak at best. Recently, one national regulatory authority has mandated a change to the labeling of one PPI based on reports of possible associated rhabdomyolysis. Thus, in this review we summarize the available evidence linking PPI use with rhabdomyolysis. The level of evidence is insufficient to establish a causal relationship and is largely based on sporadic case reports. In general, patients with suspected PPI-associated rhabdomyolysis have not been re-challenged with a PPI after recovery. The mechanism whereby PPIs might have been associated with rhabdomyolysis is unclear but possibly related to interaction with concomitantly administered drugs such as HMG-CoA reductase inhibitors (statins). For patients with rhabdomyolysis, a careful search must be made for possible etiological factors. In patients who recover from an episode of possible PPI-related rhabdomyolysis but do not have a genuine requirement for PPI treatment, the PPI should not be re-introduced. For those with a definite indication for ongoing PPI treatment, the PPI can be re-introduced but should preferably not be administered with a statin.

  5. Polyphenol Compound as a Transcription Factor Inhibitor

    Directory of Open Access Journals (Sweden)

    Seyeon Park

    2015-10-01

    Full Text Available A target-based approach has been used to develop novel drugs in many therapeutic fields. In the final stage of intracellular signaling, transcription factor–DNA interactions are central to most biological processes and therefore represent a large and important class of targets for human therapeutics. Thus, we focused on the idea that the disruption of protein dimers and cognate DNA complexes could impair the transcriptional activation and cell transformation regulated by these proteins. Historically, natural products have been regarded as providing the primary leading compounds capable of modulating protein–protein or protein-DNA interactions. Although their mechanism of action is not fully defined, polyphenols including flavonoids were found to act mostly as site-directed small molecule inhibitors on signaling. There are many reports in the literature of screening initiatives suggesting improved drugs that can modulate the transcription factor interactions responsible for disease. In this review, we focus on polyphenol compound inhibitors against dimeric forms of transcription factor components of intracellular signaling pathways (for instance, c-jun/c-fos (Activator Protein-1; AP-1, c-myc/max, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB and β-catenin/T cell factor (Tcf.

  6. Polyphenol Compound as a Transcription Factor Inhibitor.

    Science.gov (United States)

    Park, Seyeon

    2015-10-30

    A target-based approach has been used to develop novel drugs in many therapeutic fields. In the final stage of intracellular signaling, transcription factor-DNA interactions are central to most biological processes and therefore represent a large and important class of targets for human therapeutics. Thus, we focused on the idea that the disruption of protein dimers and cognate DNA complexes could impair the transcriptional activation and cell transformation regulated by these proteins. Historically, natural products have been regarded as providing the primary leading compounds capable of modulating protein-protein or protein-DNA interactions. Although their mechanism of action is not fully defined, polyphenols including flavonoids were found to act mostly as site-directed small molecule inhibitors on signaling. There are many reports in the literature of screening initiatives suggesting improved drugs that can modulate the transcription factor interactions responsible for disease. In this review, we focus on polyphenol compound inhibitors against dimeric forms of transcription factor components of intracellular signaling pathways (for instance, c-jun/c-fos (Activator Protein-1; AP-1), c-myc/max, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and β-catenin/T cell factor (Tcf)).

  7. PD-1 Checkpoint Inhibitor Associated Autoimmune Encephalitis

    Directory of Open Access Journals (Sweden)

    Stephanie Schneider

    2017-05-01

    Full Text Available Objective: To report first-hand narrative experience of autoimmune encephalitis and to briefly review currently available evidence of autoimmune encephalitis in cancer patients treated with immune checkpoint inhibitors. Setting: A case study is presented on the management of a patient who developed autoimmune encephalitis during nivolumab monotherapy occurring after 28 weeks on anti-PD-1 monotherapy (nivolumab 3 mg/kg every 2 weeks for non-small cell lung cancer. Results: No substantial improvement was observed by antiepileptic treatment. After administration of 80 mg methylprednisolone, neurologic symptoms disappeared within 24 h and the patient fully recovered. Conclusions: Immune checkpoint inhibitor treatment can lead to autoimmune encephalitis. Clinical trial data indicate a frequency of autoimmune encephalitis of ≥0.1 to <1% with a higher probability during combined or sequential anti-CTLA-4/anti-PD-1 therapy than during anti-PD-1 or anti-PD-L1 monotherapy. Further collection of evidence and translational research is warranted.

  8. Synthesis of Novel Chalcones as Acetylcholinesterase Inhibitors

    Directory of Open Access Journals (Sweden)

    Thanh-Dao Tran

    2016-07-01

    Full Text Available A new series of benzylaminochalcone derivatives with different substituents on ring B were synthesized and evaluated as inhibitors of acetylcholinesterase. The study is aimed at identification of novel benzylaminochalcones capable of blocking acetylcholinesterase activity for further development of an approach to Alzheimer’s disease treatment. These compounds were produced in moderate to good yields via Claisen-Schmidt condensation and subjected to an in vitro acetylcholinesterase inhibition assay, using Ellman’s method. The in silico docking procedure was also employed to identify molecular interactions between the chalcone compounds and the enzyme. Compounds with ring B bearing pyridin-4-yl, 4-nitrophenyl, 4-chlorophenyl and 3,4-dimethoxyphenyl moieties were discovered to exhibit significant inhibitory activities against acetylcholinesterase, with IC50 values ranging from 23 to 39 µM. The molecular modeling studies are consistent with the hypothesis that benzylaminochalcones could exert their effects as dual-binding-site acetylcholinesterase inhibitors, which might simultaneously enhance cholinergic neurotransmission and inhibit β-amyloid aggregation through binding to both catalytic and peripheral sites of the enzyme. These derivatives could be further developed to provide novel leads for the discovery of new anti-Alzheimer drugs in the future.

  9. Replication and Inhibitors of Enteroviruses and Parechoviruses

    Directory of Open Access Journals (Sweden)

    Lonneke van der Linden

    2015-08-01

    Full Text Available The Enterovirus (EV and Parechovirus genera of the picornavirus family include many important human pathogens, including poliovirus, rhinovirus, EV-A71, EV-D68, and human parechoviruses (HPeV. They cause a wide variety of diseases, ranging from a simple common cold to life-threatening diseases such as encephalitis and myocarditis. At the moment, no antiviral therapy is available against these viruses and it is not feasible to develop vaccines against all EVs and HPeVs due to the great number of serotypes. Therefore, a lot of effort is being invested in the development of antiviral drugs. Both viral proteins and host proteins essential for virus replication can be used as targets for virus inhibitors. As such, a good understanding of the complex process of virus replication is pivotal in the design of antiviral strategies goes hand in hand with a good understanding of the complex process of virus replication. In this review, we will give an overview of the current state of knowledge of EV and HPeV replication and how this can be inhibited by small-molecule inhibitors.

  10. Flavonoids as Inhibitors of Human Butyrylcholinesterase Variants

    Directory of Open Access Journals (Sweden)

    Maja Katalinić

    2014-01-01

    Full Text Available The inhibition of butyrylcholinesterase (BChE, EC 3.1.1.8 appears to be of interest in treating diseases with symptoms of reduced neurotransmitter levels, such as Alzheimer’s disease. However, BCHE gene polymorphism should not be neglected in research since it could have an effect on the expected outcome. Several well-known cholinergic drugs (e.g. galantamine, huperzine and rivastigmine originating from plants, or synthesised as derivatives of plant compounds, have shown that herbs could serve as a source of novel target-directed compounds. We focused our research on flavonoids, biologically active polyphenolic compounds found in many plants and plant-derived products, as BChE inhibitors. All of the tested flavonoids: galangin, quercetin, fisetin and luteolin reversibly inhibited usual, atypical, and fluoride-resistant variants of human BChE. The inhibition potency increased in the following order, identically for all three BChE variants: luteolininhibitor dissociation constants (Ki ranged from 10 to 170 mmol/L. We showed that no significant change in the inhibition potency of selected flavonoids exists in view of BChE polymorphism. Our results suggested that flavonoids could assist the further development of new BChE-targeted drugs for treating symptoms of neurodegenerative diseases and dementia.

  11. Matrix Metalloproteinase Responsive Delivery of Myostatin Inhibitors.

    Science.gov (United States)

    Braun, Alexandra C; Gutmann, Marcus; Ebert, Regina; Jakob, Franz; Gieseler, Henning; Lühmann, Tessa; Meinel, Lorenz

    2017-01-01

    The inhibition of myostatin - a member of the transforming growth factor (TGF-β) family - drives regeneration of functional skeletal muscle tissue. We developed a bioresponsive drug delivery system (DDS) linking release of a myostatin inhibitor (MI) to inflammatory flares of myositis to provide self-regulated MI concentration gradients within tissues of need. A protease cleavable linker (PCL) - responding to MMP upregulation - is attached to the MI and site-specifically immobilized on microparticle surfaces. The PCL disintegrated in a matrix metalloproteinase (MMP) 1, 8, and particularly MMP-9 concentration dependent manner, with MMP-9 being an effective surrogate biomarker correlating with the activity of myositis. The bioactivity of particle-surface bound as well as released MI was confirmed by luciferase suppression in stably transfected HEK293 cells responding to myostatin induced SMAD phosphorylation. We developed a MMP-responsive DDS for MI delivery responding to inflammatory flare of a diseased muscle matching the kinetics of MMP-9 upregulation, with MMP-9 kinetics matching (patho-) physiological myostatin levels. ᅟ: Graphical Abstract Schematic illustration of the matrix metalloproteinase responsive delivery system responding to inflammatory flares of muscle disease. The protease cleavable linker readily disintegrates upon entry into the diseased tissue, therby releasing the mystatin inhibitor.

  12. Nontoxic corrosion inhibitors for N80 steel in hydrochloric acid

    OpenAIRE

    M. Yadav; Debasis Behera; Usha Sharma

    2016-01-01

    The purpose of this paper is to evaluate the protective ability of 1-(2-aminoethyl)-2-oleylimidazoline (AEOI) and 1-(2-oleylamidoethyl)-2-oleylimidazoline (OAEOI) as corrosion inhibitors for N80 steel in 15% hydrochloric acid, which may find application as eco-friendly corrosion inhibitors in acidizing processes in petroleum industry. Different concentrations of synthesized inhibitors AEOI and OAEOI were added to the test solution (15% HCl) and the corrosion inhibition of N80 steel in hydroch...

  13. Aromatase inhibitors in men: effects and therapeutic options

    Directory of Open Access Journals (Sweden)

    de Jong Frank H

    2011-06-01

    Full Text Available Abstract Aromatase inhibitors effectively delay epiphysial maturation in boys and improve testosterone levels in adult men Therefore, aromatase inhibitors may be used to increase adult height in boys with gonadotropin-independent precocious puberty, idiopathic short stature and constitutional delay of puberty. Long-term efficacy and safety of the use of aromatase inhibitors has not yet been established in males, however, and their routine use is therefore not yet recommended.

  14. Inhibitors of Fatty Acid Synthase for Prostate Cancer. Revision

    Science.gov (United States)

    2013-05-01

    acetyl- cholinesterase inhibitors have been developed, many with femtomolar binding affinities (7). This body of literature also confirms that the...AD_________________ Award Number: W81XWH-09-1-0204 TITLE: Inhibitors of Fatty Acid Synthase for...May 2013 2. REPORT TYPE Revised Final 3. DATES COVERED 01 May 2009-30 Apr 2013 4. TITLE AND SUBTITLE Inhibitors of Fatty Acid Synthase for

  15. Inhibitors of Fatty Acid Synthase for Prostate Cancer

    Science.gov (United States)

    2012-05-01

    compounds. For example, numerous classes of acetyl- cholinesterase inhibitors have been developed, m any with fe mtomolar binding affinities (7). This...AD_________________ Award Number: W81XWH-09-1-0204 TITLE: Inhibitors of Fatty Acid Synthase for...CONTRACT NUMBER Inhibitors of Fatty Acid Synthase for Prostate Cancer 5b. GRANT NUMBER W81XWH-09-1-0204 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR

  16. Natural compounds as corrosion inhibitors for highly cycled systems

    Energy Technology Data Exchange (ETDEWEB)

    Quraishi, M.A.; Farooqi, I.H.; Saini, P.A. [Corrosion Research Lab., Aligarh (India)

    1999-11-01

    Strict environmental legislations have led to the development of green inhibitors in recent years. In continuation of the authors` research work on development of green inhibitors, they have investigated the aqueous extracts of three plants namely: Azadirachta indica, Punica Granatum and Momordica charantia as corrosion inhibitors for mild steel in 3% NaCl using weight loss and electrochemical methods. All the investigated compounds exhibited excellent corrosion inhibition properties comparable to that of HEDP. Azadirachta showed better scale inhibition effect than HEDP.

  17. Invertase proteinaceous inhibitor of Cyphomandra betacea Sendt fruits.

    Science.gov (United States)

    Ordóñez, R M; Isla, M I; Vattuone, M A; Sampietro, A R

    2000-01-01

    This work describes a new invertase proteinaceous inhibitor from Cyphomandra betacea Sendt. (tomate de arbol) fruits. The proteinaceous inhibitor was isolated and purified from a cell wall preparation. The pH stability, kinetics of the inhibition of the C. betacea invertase, inhibition of several higher plant invertases and lectin nature of the inhibitor were studied. The inhibitor structure involves a single polypeptide (Mr = 19000), as shown by gel filtration and SDS-PAGE determinations. N-terminal aminoacid sequence was determined. The properties and some structural features of the inhibitor are compared with the proteinaceous inhibitors from several plant species (Beta vulgaris L., Ipomoea batatas L. and Lycopersicon esculentum Mill.). All these inhibitors share lectinic properties, some common epitopes, some aminoacid sequences and a certain lack of specificity towards invertases of different species, genera and even plant family. In consequence, the inhibitors appear to belong to the same lectin family. It is now known that some lectins are part of the defence mechanism of higher plants against fungi and bacteria and this is a probable role of the proteinaceous inhibitors.

  18. Predicting DPP-IV inhibitors with machine learning approaches

    Science.gov (United States)

    Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

    2017-04-01

    Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

  19. Experimental and theoretical studies of benzoxazines corrosion inhibitors

    Directory of Open Access Journals (Sweden)

    Abdulhadi Kadhim

    Full Text Available 2-Methyl-4H-benzo[d][1,3]oxazin-4-one (BZ1 and 3-amino-2-methylquinazolin-4(3H-one (BZ2 were evaluated for their corrosion inhibition properties on mild steel (MS in hydrochloric acid solution by weight loss technique and scanning electron microscopy. Results show the inhibition efficiency values depend on the amount of nitrogen in the inhibitor, the inhibitor concentration and the inhibitor molecular weight with maximum inhibition efficiency of 89% and 65% for BZ2 and BZ1 at highest concentration of the compounds. Keywords: Methylquinazoline, Benzoxazines, Corrosion, Inhibitors

  20. Cysteine peptidases and their inhibitors in breast and genital cancer.

    Directory of Open Access Journals (Sweden)

    Magdalena Milan

    2010-11-01

    Full Text Available Cysteine proteinases and their inhibitors probably play the main role in carcinogenesis and metastasis. The metastasis process need external proteolytic activities that pass several barriers which are membranous structures of the connective tissue which includes, the basement membrane of blood vessels. Activities of the proteinases are regulated by endogenous inhibitors and activators. The imbalance between cysteine proteinases and cystatins seems to be associated with an increase in metastatic potential in some tumors. It has also been reported that proteinase inhibitors, specific antibodies for these enzymes and inhibition of the urokinase receptor may prevent cancer cell invasion. Some proteinase inhibitor could serve as agents for cancer treatment.

  1. Insights into the molecular evolution of peptidase inhibitors in arthropods.

    Science.gov (United States)

    Alonso, Joaquin; Martinez, Manuel

    2017-01-01

    Peptidase inhibitors are key proteins involved in the control of peptidases. In arthropods, peptidase inhibitors modulate the activity of peptidases involved in endogenous physiological processes and peptidases of the organisms with which they interact. Exploring available arthropod genomic sequences is a powerful way to obtain the repertoire of peptidase inhibitors in every arthropod species and to understand the evolutionary mechanisms involved in the diversification of this kind of proteins. A genomic comparative analysis of peptidase inhibitors in species belonging to different arthropod taxonomic groups was performed. The results point out: i) species or clade-specific presence is shown for several families of peptidase inhibitors; ii) multidomain peptidase inhibitors are commonly found in many peptidase inhibitor families; iii) several families have a wide range of members in different arthropod species; iv) several peptidase inhibitor families show species-specific (or clade-specific) gene family expansions; v) functional divergence may be assumed for particular clades; vi) passive expansions may be used by natural selection to fix adaptations. In conclusion, conservation and divergence of duplicated genes and the potential recruitment as peptidase inhibitors of proteins from other families are the main mechanisms used by arthropods to fix diversity. This diversity would be associated to the control of target peptidases and, as consequence, to adapt to specific environments.

  2. The safety of proton pump inhibitors in pregnancy

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Lauge; Sørensen, Henrik Toft; Thulstrup, Ane Marie

    1999-01-01

    AIM: To assess the safety of proton pump inhibitors during pregnancy. METHODS: Fifty-one pregnant women exposed to proton pump inhibitors around the time of conception or during pregnancy were compared with 13 327 controls without exposure to any prescribed drug in a population-based study based...... birth weight or number of preterm deliveries in pregnancies exposed to proton pump inhibitors. However, further monitoring is warranted in order to establish or rule out a potential association between the use of proton pump inhibitors and increased risk of either cardiac malformations or preterm birth....

  3. Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

    Directory of Open Access Journals (Sweden)

    Shohei Sakuda

    2014-03-01

    Full Text Available Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control.

  4. Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

    Science.gov (United States)

    Sakuda, Shohei; Prabowo, Diyan Febri; Takagi, Keiko; Shiomi, Kazuro; Mori, Mihoko; Ōmura, Satoshi; Nagasawa, Hiromichi

    2014-01-01

    Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A) inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III) and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control. PMID:24674936

  5. Genome scan of clot lysis time and its association with thrombosis in a protein C-deficient kindred.

    Science.gov (United States)

    Meltzer, M E; Hasstedt, S J; Vossen, C Y; Callas, P W; DE Groot, Ph G; Rosendaal, F R; Lisman, T; Bovill, E G

    2011-07-01

     Previously, we found increased clot-lysis time (CLT), as measured with a plasma-based assay, to increase the risk of venous thrombosis in two population-based case-control studies. The genes influencing CLT are as yet unknown.  We tested CLT as risk factor for venous thrombosis in Kindred Vermont II (n = 346), a pedigree suffering from a high thrombosis risk, partially attributable to a type I protein C deficiency. Furthermore, we tested for quantitative trait loci (QTLs) for CLT, using variance component linkage analysis.  Protein C-deficient family members had shorter CLTs than non-deficient members (median CLT 67 min vs. 75 min). One standard deviation increase in CLT increased the risk of venous thrombosis 2.4-fold in non-deficient family members. Protein C deficiency without elevated CLT increased the risk 6.9-fold. Combining both risk factors yielded a 27.8-fold increased risk. The heritability of CLT was 42-52%. We found suggestive evidence of linkage on chromosome 11 (62 cM), partly explained by the prothrombin 20210A mutation, and on chromosome 13 (52 cM). Thrombin-activatable fibrinolysis inhibitor genotypes did not explain the variation in CLT. Hypofibrinolysis appears to increase thrombosis risk in this family, especially in combination with protein C deficiency. Protein C deficiency is associated with short CLT. CLT is partly genetically regulated. Suggestive QTLs were found on chromosomes 11 and 13. © 2011 International Society on Thrombosis and Haemostasis.

  6. Inga laurina trypsin inhibitor (ILTI) obstructs Spodoptera frugiperda trypsins expressed during adaptive mechanisms against plant protease inhibitors.

    Science.gov (United States)

    Machado, Suzy Wider; de Oliveira, Caio Fernando Ramalho; Zério, Neide Graciano; Parra, José Roberto Postali; Macedo, Maria Lígia Rodrigues

    2017-08-01

    Plant protease inhibitors (PIs) are elements of a common plant defense mechanism induced in response to herbivores. The fall armyworm, Spodoptera frugiperda, a highly polyphagous lepidopteran pest, responds to various PIs in its diet by expressing genes encoding trypsins. This raises the question of whether the PI-induced trypsins are also inhibited by other PIs, which we posed as the hypothesis that Inga laurina trypsin inhibitor (ILTI) inhibits PI-induced trypsins in S. frugiperda. In the process of testing our hypothesis, we compared its properties with those of selected PIs, soybean Kunitz trypsin inhibitor (SKTI), Inga vera trypsin inhibitor (IVTI), Adenanthera pavonina trypsin inhibitor (ApTI), and Entada acaciifolia trypsin inhibitor (EATI). We report that ILTI is more effective in inhibiting the induced S. frugiperda trypsins than SKTI and the other PIs, which supports our hypothesis. ILTI may be more appropriate than SKTI for studies regarding adaptive mechanisms to dietary PIs. © 2017 Wiley Periodicals, Inc.

  7. Efficacy and Safety of a Pharmaco-Invasive Strategy With Half-Dose Alteplase Versus Primary Angioplasty in ST-Segment-Elevation Myocardial Infarction: EARLY-MYO Trial (Early Routine Catheterization After Alteplase Fibrinolysis Versus Primary PCI in Acute ST-Segment-Elevation Myocardial Infarction).

    Science.gov (United States)

    Pu, Jun; Ding, Song; Ge, Heng; Han, Yaling; Guo, Jinchen; Lin, Rong; Su, Xi; Zhang, Heng; Chen, Lianglong; He, Ben

    2017-10-17

    Timely primary percutaneous coronary intervention (PPCI) cannot be offered to all patients with ST-segment-elevation myocardial infarction (STEMI). Pharmaco-invasive (PhI) strategy has been proposed as a valuable alternative for eligible patients with STEMI. We conducted a randomized study to compare the efficacy and safety of a PhI strategy with half-dose fibrinolytic regimen versus PPCI in patients with STEMI. The EARLY-MYO trial (Early Routine Catheterization After Alteplase Fibrinolysis Versus Primary PCI in Acute ST-Segment-Elevation Myocardial Infarction) was an investigator-initiated, prospective, multicenter, randomized, noninferiority trial comparing a PhI strategy with half-dose alteplase versus PPCI in patients with STEMI 18 to 75 years of age presenting ≤6 hours after symptom onset but with an expected PCI-related delay. The primary end point of the study was complete epicardial and myocardial reperfusion after PCI, defined as thrombolysis in myocardial infarction flow grade 3, thrombolysis in myocardial infarction myocardial perfusion grade 3, and ST-segment resolution ≥70%. We also measured infarct size and left ventricular ejection fraction with cardiac magnetic resonance and recorded 30-day clinical and safety outcomes. A total of 344 patients from 7 centers were randomized to PhI (n=171) or PPCI (n=173). PhI was noninferior (and even superior) to PPCI for the primary end point (34.2% versus 22.8%, P noninferiority <0.05, P superiority =0.022), with no significant differences in the frequency of the individual components of the combined end point: thrombolysis in myocardial infarction flow 3 (91.3% versus 89.2%, P =0.580), thrombolysis in myocardial infarction myocardial perfusion grade 3 (65.8% versus 62.9%, P =0.730), and ST-segment resolution ≥70% (50.9% versus 45.5%, P =0.377). Infarct size (23.3%±11.3% versus 25.8%±13.7%, P =0.101) and left ventricular ejection fraction (52.2%±11.0% versus 51.4%±12.0%, P =0.562) were similar in both

  8. Identification of fermentation inhibitors in wood hydrolyzates and removal of inhibitors by ion exchange and liquid-liquid extraction

    Science.gov (United States)

    Luo, Caidian

    1998-12-01

    Common methods employed in the ethanol production from biomass consist of chemical or enzymatic degradation of biomass into sugars and then fermentation of sugars into ethanol or other chemicals. However, some degradation products severely inhibit the fermentation processes and substantially reduce the efficiency of ethanol production. How to remove inhibitors from the reaction product mixture and increase the production efficiency are critical in the commercialization of any processes of energy from biomass. The present study has investigated anion exchange and liquid-liquid extraction as potential methods for inhibitor removal. An analytical method has been developed to identify the fermentation inhibitors in a hydrolyzate. The majority of inhibitors present in hybrid poplar hydrolyzate have positively been identified. Ion exchange with weak basic Dowex-MWA-1 resin has been proved to be an effective mean to remove fermentation inhibitors from hybrid poplar hydrolyzate and significantly increase the fermentation productivity. Extraction with n-butanol might be a preferred way to remove inhibitors from wood hydrolyzates and improve the fermentability of sugars in the hydrolyzates. n-Butanol also removes some glucose, mannose and xylose from the hydrolyzate. Inhibitor identification reveals that lignin and sugar degradation compounds including both aromatic and aliphatic aldehydes and carboxylic acids formed in hydrolysis, plus fatty acids and other components from wood extractives are major fermentation inhibitors in Sacchromyces cerevisiae fermentation. There are 35 components identified as fermentation inhibitors. Among them, 4-hydroxy benzoic acid, 3,4-dihydroxy benzoic acid, syringic acid, syringaldehyde, and ferulic acid are among the most abundant aromatic inhibitors in hybrid poplar hydrolyzate. The conversion of aldehyde groups into carboxylic acid groups in the nitric acid catalyzed hydrolysis reduces the toxicity of the hydrolyzate. A wide spectrum of

  9. Proton pump inhibitors inhibit pancreatic secretion

    DEFF Research Database (Denmark)

    Wang, Jing; Barbuskaite, Dagne; Tozzi, Marco

    2015-01-01

    +/K+-ATPases are expressed and functional in human pancreatic ducts and whether proton pump inhibitors (PPIs) have effect on those. Here we show that the gastric HKα1 and HKβ subunits (ATP4A; ATP4B) and non-gastric HKα2 subunits (ATP12A) of H+/K+-ATPases are expressed in human pancreatic cells. Pumps have similar...... of major ions in secretion follow similar excretory curves in control and PPI treated animals. In addition to HCO3-, pancreas also secretes K+. In conclusion, this study calls for a revision of the basic model for HCO3- secretion. We propose that proton transport is driving secretion, and that in addition...

  10. Neuromuscular complications of immune checkpoint inhibitor therapy.

    Science.gov (United States)

    Kolb, Noah A; Trevino, Christopher R; Waheed, Waqar; Sobhani, Fatemeh; Landry, Kara K; Thomas, Alissa A; Hehir, Mike

    2018-01-17

    Immune checkpoint inhibitor (ICPI) therapy unleashes the body's natural immune system to fight cancer. ICPIs improve overall cancer survival, however, the unbridling of the immune system may induce a variety of immune-related adverse events. Neuromuscular immune complications are rare but they can be severe. Myasthenia gravis and inflammatory neuropathy are the most common neuromuscular adverse events but a variety of others including inflammatory myopathy are reported. The pathophysiologic mechanism of these autoimmune disorders may differ from that of non-ICPI-related immune diseases. Accordingly, while the optimal treatment for ICPI-related neuromuscular disorders generally follows a traditional paradigm, there are important novel considerations in selecting appropriate immunosuppressive therapy. This review presents 2 new cases, a summary of neuromuscular ICPI complications, and an approach to the diagnosis and treatment of these disorders. Muscle Nerve, 2018. © 2018 Wiley Periodicals, Inc.

  11. Phosphodiesterase Type 5 Inhibitors, Sport and Doping.

    Science.gov (United States)

    Di Luigi, Luigi; Sansone, Massimiliano; Sansone, Andrea; Ceci, Roberta; Duranti, Guglielmo; Borrione, Paolo; Crescioli, Clara; Sgrò, Paolo; Sabatini, Stefania

    Phosphodiesterase type 5 inhibitors (PDE5i) (e.g., sildenafil, tadalafil, vardenafil, and avanafil) are drugs commonly used to treat erectile dysfunction, pulmonary arterial hypertension, and benign prostatic hyperplasia. PDE5i are not prohibited by the World Anti-Doping Agency (WADA) but are alleged to be frequently misused by healthy athletes to improve sporting performance. In vitro and in vivo studies have reported various effects of PDE5i on cardiovascular, muscular, metabolic, and neuroendocrine systems and the potential, therefore, to enhance performance of healthy athletes during training and competition. This suggests well-controlled research studies to examine the ergogenic effects of PDE5i on performance during activities that simulate real sporting situations are warranted to determine if PDE5i should be included on the prohibited WADA list. In the meantime, there is concern that some otherwise healthy athletes will continue to misuse PDE5i to gain an unfair competitive advantage over their competitors.

  12. Developing BACE-1 inhibitors for FXS

    Directory of Open Access Journals (Sweden)

    Cara J Westmark

    2013-05-01

    Full Text Available Fragile X syndrome (FXS is a debilitating genetic disorder with no cure and few therapeutic options. Excessive signaling through metabotropic glutamate receptor 5 (mGluR5 in FXS leads to increased translation of numerous synaptic proteins and exaggerated long-term depression (LTD. Two of the overexpressed proteins are amyloid-beta protein precursor (APP and its metabolite amyloid-beta (Aβ, which have been well-studied in Alzheimer’s disease (AD. Here we discus the possibility that pharmaceuticals under study for the modulation of these proteins in AD might be viable therapeutic strategies for FXS. Specifically, a recently identified acetyltransferase (ATase inhibitor that reduces the levels and activity of β-site APP cleaving enzyme (BACE-1 has strong potential to attenuate BACE-1 activity and maintain homeostatic levels APP catabolites in FXS.

  13. Coumarins as cholinesterase inhibitors: A review.

    Science.gov (United States)

    de Souza, Luana G; Rennã, Magdalena N; Figueroa-Villar, Jose D

    2016-07-25

    The first report in literature of the isolation of coumarin was in the year 1820. After this report, other papers were published demonstrating the isolation and synthesis of coumarin and analogues. These compounds have been studying along the years for several different pathologies. One of these pathologies was Alzheimer's disease (AD), being the main cause of dementia in the contemporary world. There are two hypotheses to explain the pathogenesis mechanism and disease symptoms, then having the "amyloid hypothesis" and the "cholinergic hypothesis". Some drugs for AD are based on the theory of "cholinergic hypothesis", which objective is to increase the concentration of ACh in the synaptic cleft by the inhibition of cholinesterases. Over the last twenty years, many studies with coumarins compounds were reported as cholinesterases inhibitors. The aim of the present review is to discuss the studies and development of new compounds for AD treatment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. New Acetylcholinesterase Inhibitors for Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Mona Mehta

    2012-01-01

    Full Text Available Acetylcholinesterase (AChE remains a highly viable target for the symptomatic improvement in Alzheimer's disease (AD because cholinergic deficit is a consistent and early finding in AD. The treatment approach of inhibiting peripheral AchE for myasthenia gravis had effectively proven that AchE inhibition was a reachable therapeutic target. Subsequently tacrine, donepezil, rivastigmine, and galantamine were developed and approved for the symptomatic treatment of AD. Since then, multiple cholinesterase inhibitors (ChEI continue to be developed. These include newer ChEIs, naturally derived ChEIs, hybrids, and synthetic analogues. In this paper, we summarize the different types of ChEIs in development and their respective mechanisms of actions. This pharmacological approach continues to be active with many promising compounds.

  15. Endogenous Natural Complement Inhibitor Regulates Cardiac Development

    DEFF Research Database (Denmark)

    Mortensen, Simon A; Skov, Louise L; Kjaer-Sorensen, Kasper

    2017-01-01

    mechanisms during fetal development and adult homeostasis. In this article, we describe the function of an endogenous complement inhibitor, mannan-binding lectin (MBL)-associated protein (MAp)44, in regulating the composition of a serine protease-pattern recognition receptor complex, MBL-associated serine...... of MAp44 caused impaired cardiogenesis, lowered heart rate, and decreased cardiac output. These defects were associated with aberrant neural crest cell behavior. We found that MAp44 competed with MASP-3 for pattern recognition molecule interaction, and knockdown of endogenous MAp44 expression could...... be rescued by overexpression of wild-type MAp44. Our observations provide evidence that immune molecules are centrally involved in the orchestration of cardiac tissue development....

  16. Histone deacetylase inhibitors in multiple myeloma

    Directory of Open Access Journals (Sweden)

    Sarah Deleu

    2009-06-01

    Full Text Available Novel drugs such as bortezomib and high dose chemotherapy combined with stem cell transplantation improved the outcome of multiple myeloma patients in the past decade. However, multiple myeloma often remains incurable due to the development of drug resistance governed by the bone marrow micro-environment. Therefore targeting new pathways to overcome this resistance is needed. Histone deacetylase (HDAC inhibitors represent a new class of anti-myeloma agents. Inhibiting HDACs results in histone hyperacetylation and alterations in chromatine structure, which, in turn, cause growth arrest differentiation and/or apoptosis in several tumor cells. Here we summarize the molecular actions of HDACi as a single agent or in combination with other drugs in different in vitro and in vivo myeloma models and in (preclinical trials.

  17. Molecular modeling of auxin transport inhibitors

    International Nuclear Information System (INIS)

    Gardner, G.; Black-Schaefer, C.; Bures, M.G.

    1990-01-01

    Molecular modeling techniques have been used to study the chemical and steric properties of auxin transport inhibitors. These bind to a specific site on the plant plasma membrane characterized by its affinity for N-1-naphthylphthalamic acid (NPA). A three-dimensional model was derived from critical features of ligands for the NPA receptor, and a suggested binding conformation is proposed. This model, along with three-dimensional structural searching techniques, was then used to search the Abbott corporate database of chemical structures. Of the 467 compounds that satisfied the search criteria, 77 representative molecules were evaluated for their ability to compete for [ 3 H]NPA binding to corn microsomal membranes. Nineteen showed activity that ranged from 16 to 85% of the maximum NPA binding. Four of the most active of these, from chemical classes not included in the original compound set, also inhibited polar auxin transport through corn coleoptile sections

  18. Carbocyclic Carbohydrate Mimics as Potential Glycosidase Inhibitors

    DEFF Research Database (Denmark)

    Fanefjord, Mette; Lundt, Inge

    It has been proven that aminocyclopentanols having the aminogroup adjacent to a carbon sidechain could be potential anomer-selective glycosidase inhibitors [1]. A successful pathway for synthesising mimics to L-carbohydrates 2, by introducing nitrogen to the C6 position in compound 1, has been...... developed in our group. A similar strategy has been used for synthesising mimics of D-carbohydrates. The α,β-unsaturated lactone 3 was cyclised to compound 4 which was further transformed into 5. The nitrogen functionality in compound 7 is introduced by an Overman rearrangement of 6 and the hydroxyl...... functionalities was introduced by either epoxidation or dihydroxylation of 7. Finally, reduction of the lactone ring led to the sugar mimics 8. The synthesis of several isomers of 8 will be presented. [1] a) Kleban, M. ; Hilgers, P. ; Greul, J.N. ; Kugler, R.D. ; Li, J. ; Picasso, S. ; Vogel, P. ; Jäger, V. Chem...

  19. Use of proteasome inhibitors in anticancer therapy

    Directory of Open Access Journals (Sweden)

    Sara M. Schmitt

    2011-10-01

    Full Text Available The importance of the ubiquitin-proteasome pathway to cellular function has brought it to the forefront in the search for new anticancer therapies. The ubiquitin-proteasome pathway has proven promising in targeting various human cancers. The approval of the proteasome inhibitor bortezomib for clinical treatment of relapsed/refractory multiple myeloma and mantle cell lymphoma has validated the ubiquitin-proteasome as a rational target. Bortezomib has shown positive results in clinical use but some toxicity and side effects, as well as resistance, have been observed, indicating that further development of novel, less toxic drugs is necessary. Because less toxic drugs are necessary and drug development can be expensive and time-consuming, using existing drugs that can target the ubiquitin-proteasome pathway in new applications, such as cancer therapy, may be effective in expediting the regulatory process and bringing new drugs to the clinic. Toward this goal, previously approved drugs, such as disulfiram, as well as natural compounds found in common foods, such as green tea polyphenol (--EGCG and the flavonoid apigenin, have been investigated for their possible proteasome inhibitory and cell death inducing abilities. These compounds proved quite promising in preclinical studies and have now moved into clinical trials, with preliminary results that are encouraging. In addition to targeting the catalytic activity of the proteasome pathway, upstream regulators, such as the 19S regulatory cap, as well as E1, E2, and E3, are now being investigated as potential drug targets. This review outlines the development of novel proteasome inhibitors from preclinical to clinical studies, highlighting their abilities to inhibit the tumor proteasome and induce apoptosis in several human cancers.

  20. Molecular Dynamics simulations of Inhibitor of Apoptosis Proteins and identification of potential small molecule inhibitors.

    Science.gov (United States)

    Jayakumar, Jayanthi; Anishetty, Sharmila

    2014-05-01

    Chemotherapeutic resistance due to over expression of Inhibitor of Apoptosis Proteins (IAPs) XIAP, survivin and livin has been observed in various cancers. In the current study, Molecular Dynamics (MD) simulations were carried out for all three IAPs and a common ligand binding scaffold was identified. Further, a novel sequence based motif specific to these IAPs was designed. SMAC is an endogenous inhibitor of IAPs. Screening of ChemBank for compounds similar to lead SMAC-non-peptidomimetics yielded a cemadotin related compound NCIMech_000654. Cemadotin is a derivative of natural anti-tumor peptide dolastatin-15; hence these compounds were docked against all three IAPs. Based on our analysis, we propose that NCIMech_000654/dolastatin-15/cemadotin derivatives may be investigated for their potential in inhibiting XIAP, survivin and livin. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Effect of biocides and anionic homopolymeric inhibitors on the ...

    African Journals Online (AJOL)

    This paper describes the effect of biocides and of the anionic homopolymeric inhibitors on the precipitation behavior of calcium fluoride (CaF2).The efficiency of inhibitors in the presence and absence of biocides was calculated using the half-life (t1/2) approach, where 50% of the concentration has been precipitated.

  2. High throughput in vivo protease inhibitor selection platform

    DEFF Research Database (Denmark)

    2017-01-01

    The invention relates to a recombinant microbial cell comprising a selection platform for screening for a protease inhibitor, wherein the platform comprises transgenes encoding a protease having selective peptide bond cleavage activity at a recognition site amino acid sequence; and transgenes...... platform for screening for a protease inhibitor....

  3. Regulation of collagenase inhibitor production in chondrosarcoma chondrocytes

    International Nuclear Information System (INIS)

    Harper, J.; Harper, E.

    1987-01-01

    Swarm rat chondrosarcoma chondrocytes produce an inhibitor of collagenase. This inhibitor is similar to those isolated from normal cartilage tissues. These cells will synthesize proteins in the absence of serum. Since serum contains inhibitors of collagenase, it is necessary to culture cells without serum in order to obtain accurate measurements of enzyme and inhibitor levels. They examined the effect of insulin on inhibitor secretion by cultures of Swarm rat chondrosarcoma chondrocytes. They observed a 2.5 to 3.5 fold stimulation of inhibitory activity in the presence of as little as 10 ng/ml insulin as compared to controls in serum free Dulbecco's modified Eagle's medium supplemented with 4.5 g/l glucose. The units of inhibitor were determined over a 7 day culture period. Medium was harvested daily and assayed for collagenase activity and for inhibition of a known collagenase from rabbit skin or human skin, using the 14 C-glycine peptide release assay. The amount of inhibitor obtained from days 2 through 7 were: 1.4 unit (control), 3.8 units (10 ng/ml insulin), 5.2 units (1 μg/ml insulin). The addition of 1 mM dibutyryl cyclic AMP to these chondrocytes in the presence of 1 μg/ml insulin caused a decrease in the level of inhibitor, suggesting that a dephosphorylation event may be necessary for this stimulation by insulin to occur

  4. Nontoxic corrosion inhibitors for N80 steel in hydrochloric acid

    Directory of Open Access Journals (Sweden)

    M. Yadav

    2016-11-01

    Full Text Available The purpose of this paper is to evaluate the protective ability of 1-(2-aminoethyl-2-oleylimidazoline (AEOI and 1-(2-oleylamidoethyl-2-oleylimidazoline (OAEOI as corrosion inhibitors for N80 steel in 15% hydrochloric acid, which may find application as eco-friendly corrosion inhibitors in acidizing processes in petroleum industry. Different concentrations of synthesized inhibitors AEOI and OAEOI were added to the test solution (15% HCl and the corrosion inhibition of N80 steel in hydrochloric acid medium containing inhibitors was tested by weight loss, potentiodynamic polarization and AC impedance measurements. Influence of temperature (298–323 K on the inhibition behavior was studied. Surface studies were performed by using FTIR spectra and SEM. Both the inhibitors, AEOI and OAEOI at 150 ppm concentration show maximum efficiency 90.26% and 96.23%, respectively at 298 K in 15% HCl solution. Both the inhibitors act as mixed corrosion inhibitors. The adsorption of the corrosion inhibitors at the surface of N80 steel is the root cause of corrosion inhibition.

  5. Protein C Inhibitor-A Novel Antimicrobial Agent

    NARCIS (Netherlands)

    Malmström, E.; Mörgelin, M.; Malmsten, M.; Johansson, L.; Norrby-Teglund, A.; Shannon, O.; Schmidtchen, A.; Meijers, J.C.M.; Herwald, H.

    2009-01-01

    Protein C inhibitor (PCI) is a heparin-binding serine proteinase inhibitor belonging to the family of serpin proteins. Here we describe that PCI exerts broad antimicrobial activity against bacterial pathogens. This ability is mediated by the interaction of PCI with lipid membranes, which

  6. A simple radiometric in vitro assay for acetylcholinesterase inhibitors

    International Nuclear Information System (INIS)

    Guilarte, T.R.; Burns, H.D.; Dannals, R.F.; Wagner, H.N. Jr.

    1983-01-01

    A radiometric method for screening acetylcholinesterase inhibitors has been described. The method is based on the production of [ 14 C]carbon dioxide from the hydrolysis of acetylcholine. The inhibitory concentration at 50% (IC50) values for several known acetylcholinesterase inhibitors were in agreement with literature values. The new radiometric method is simple, inexpensive, and has the potential for automation

  7. Replacement inhibitors for tank farm cooling coil systems

    International Nuclear Information System (INIS)

    Hsu, T.C.

    1995-01-01

    Sodium chromate has been an effective corrosion inhibitor for the cooling coil systems in Savannah River Site (SRS) waste tanks for over 40 years. Due to their age and operating history, cooling coils occasionally fail allowing chromate water to leak into the environment. When the leaks spill 10 lbs. or more of sodium chromate over a 24-hr period, the leak incidents are classified as Unusual Occurrences (UO) per CERCLA (Comprehensive Environmental Response, Compensation and Liability Act). The cost of reporting and cleaning up chromate spills prompted High Level Waste Engineering (HLWE) to initiate a study to investigate alternative tank cooling water inhibitor systems and the associated cost of replacement. Several inhibitor systems were investigated as potential alternatives to sodium chromate. All would have a lesser regulatory impact, if a spill occurred. However, the conversion cost is estimated to be $8.5 million over a period of 8 to 12 months to convert all 5 cooling systems. Although each of the alternative inhibitors examined is effective in preventing corrosion, there is no inhibitor identified that is as effective as chromate. Assuming 3 major leaks a year (the average over the past several years), the cost of maintaining the existing inhibitor was estimated at $0.5 million per year. Since there is no economic or regulatory incentive to replace the sodium chromate with an alternate inhibitor, HLWE recommends that sodium chromate continue to be used as the inhibitor for the waste tank cooling systems

  8. Detecting and treating breast cancer resistance to EGFR inhibitors

    Science.gov (United States)

    Moonlee, Sun-Young; Bissell, Mina J.; Furuta, Saori; Meier, Roland; Kenny, Paraic A.

    2016-04-05

    The application describes therapeutic compositions and methods for treating cancer. For example, therapeutic compositions and methods related to inhibition of FAM83A (family with sequence similarity 83) are provided. The application also describes methods for diagnosing cancer resistance to EGFR inhibitors. For example, a method of diagnosing cancer resistance to EGFR inhibitors by detecting increased FAM83A levels is described.

  9. Phytochemicals as Green Corrosion Inhibitors in Various Corrosive ...

    African Journals Online (AJOL)

    There is an intensive effort underway to develop new plant origin corrosion inhibitors for metal subjected to various environmental conditions. These efforts have been motivated by the desire to replace toxic inhibitors used for mitigation of corrosion of various metals and alloys in aqueous solutions. Plants represent a class ...

  10. Novel guanidine-based inhibitors of inosine monophosphate dehydrogenase.

    Science.gov (United States)

    Iwanowicz, Edwin J; Watterson, Scott H; Liu, Chunjian; Gu, Henry H; Mitt, Toomas; Leftheris, Katerina; Barrish, Joel C; Fleener, Catherine A; Rouleau, Katherine; Sherbina, N Z; Hollenbaugh, Diane L

    2002-10-21

    A series of novel guanidine-based small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH) was explored. IMPDH catalyzes the rate determining step in guanine nucleotide biosynthesis and is a target for anticancer, immunosuppressive and antiviral therapy. The synthesis and the structure-activity relationships (SARs), derived from in vitro studies, for this new series of inhibitors is given.

  11. DNA-linked Inhibitor Antibody Assay (DIANA) for sensitive and selective enzyme detection and inhibitor screening

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Václav; Schimer, Jiří; Tykvart, Jan; Knedlík, Tomáš; Vik, V.; Majer, Pavel; Konvalinka, Jan; Šácha, Pavel

    2017-01-01

    Roč. 45, č. 2 (2017), č. článku e10. ISSN 0305-1048 R&D Projects: GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : quantitative PCR * enzyme detection * inhibitor screening Subject RIV: CE - Biochemistry OBOR OECD: Biochemical research methods Impact factor: 10.162, year: 2016 https:// academic .oup.com/nar/article-lookup/doi/10.1093/nar/gkw853

  12. The cardiovascular safety trials of DPP-4 inhibitors, GLP-1 agonists, and SGLT2 inhibitors.

    Science.gov (United States)

    Secrest, Matthew H; Udell, Jacob A; Filion, Kristian B

    2017-04-01

    In this paper, we review the results of large, double-blind, placebo-controlled randomized trials mandated by the US Food and Drug Administration to examine the cardiovascular safety of newly-approved antihyperglycemic agents in patients with type 2 diabetes. The cardiovascular effects of dipeptidyl peptidase-4 (DPP-4) inhibitors remain controversial: while these drugs did not reduce or increase the risk of primary, pre-specified composite cardiovascular outcomes, one DPP-4 inhibitor (saxagliptin) increased the risk of hospitalization for heart failure in the overall population; another (alogliptin) demonstrated inconsistent effects on heart failure hospitalization across subgroups of patients, and a third (sitagliptin) demonstrated no effect on heart failure. Evidence for cardiovascular benefits of glucagon-like peptide-1 (GLP-1) agonists has been similarly heterogeneous, with liraglutide and semaglutide reducing the risk of composite cardiovascular outcomes, but lixisenatide having no reduction or increase in cardiovascular risk. The effect of GLP-1 agonists on retinopathy remains a potential concern. In the only completed trial to date to assess a sodium-glucose cotransporter-2 (SGLT2) inhibitor, empagliflozin reduced the risk of composite cardiovascular endpoints, predominantly through its impact on cardiovascular mortality and heart failure hospitalization. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Characterization of inhibitor(s) of β-glucuronidase enzyme activity in GUS-transgenic wheat

    KAUST Repository

    Ramadan, Ahmed M Ali; Eissa, Hala F.; El-Domyati, Fotouh M.; Saleh, Osama Mesilhy; Ibrahim, Nasser E.; Salama, M. I.; Mahfouz, Magdy M.; Bahieldin, Ahmed M.

    2011-01-01

    The uidA gene, encoding for β-glucuronidase (GUS), is the most frequently used reporter gene in plants. As a reporter enzyme, GUS can be assayed both qualitatively and quantitatively. In wheat, there are numerous reports of failure in detecting GUS enzyme activity in tissues of transgenic plants, while other reports have suggested presence of β-glucuronidase inhibitor(s) in wheat tissues. In the present study, we show that the β-glucuronidase enzyme activity is not only tissue-specific but also genotype-dependent. Our data demonstrate that the glucuronic acid could be the candidate inhibitor for β-glucuronidase enzyme activity in wheat leaves and roots. It should be noted that the assays to detect β-glucuronidase enzyme activity in wheat should be interpreted carefully. Based on the data of our present study, we recommend studying the chemical pathways, the unintended effects and the possible loss-of-function of any candidate transgene prior to transformation experiments. © 2011 Springer Science+Business Media B.V.

  14. Characterization of inhibitor(s) of β-glucuronidase enzyme activity in GUS-transgenic wheat

    KAUST Repository

    Ramadan, Ahmed M Ali

    2011-06-26

    The uidA gene, encoding for β-glucuronidase (GUS), is the most frequently used reporter gene in plants. As a reporter enzyme, GUS can be assayed both qualitatively and quantitatively. In wheat, there are numerous reports of failure in detecting GUS enzyme activity in tissues of transgenic plants, while other reports have suggested presence of β-glucuronidase inhibitor(s) in wheat tissues. In the present study, we show that the β-glucuronidase enzyme activity is not only tissue-specific but also genotype-dependent. Our data demonstrate that the glucuronic acid could be the candidate inhibitor for β-glucuronidase enzyme activity in wheat leaves and roots. It should be noted that the assays to detect β-glucuronidase enzyme activity in wheat should be interpreted carefully. Based on the data of our present study, we recommend studying the chemical pathways, the unintended effects and the possible loss-of-function of any candidate transgene prior to transformation experiments. © 2011 Springer Science+Business Media B.V.

  15. Classification of Breast Cancer Resistant Protein (BCRP) Inhibitors and Non-Inhibitors Using Machine Learning Approaches.

    Science.gov (United States)

    Belekar, Vilas; Lingineni, Karthik; Garg, Prabha

    2015-01-01

    The breast cancer resistant protein (BCRP) is an important transporter and its inhibitors play an important role in cancer treatment by improving the oral bioavailability as well as blood brain barrier (BBB) permeability of anticancer drugs. In this work, a computational model was developed to predict the compounds as BCRP inhibitors or non-inhibitors. Various machine learning approaches like, support vector machine (SVM), k-nearest neighbor (k-NN) and artificial neural network (ANN) were used to develop the models. The Matthews correlation coefficients (MCC) of developed models using ANN, k-NN and SVM are 0.67, 0.71 and 0.77, and prediction accuracies are 85.2%, 88.3% and 90.8% respectively. The developed models were tested with a test set of 99 compounds and further validated with external set of 98 compounds. Distribution plot analysis and various machine learning models were also developed based on druglikeness descriptors. Applicability domain is used to check the prediction reliability of the new molecules.

  16. Aggregation of trypsin and trypsin inhibitor by Al cation.

    Science.gov (United States)

    Chanphai, P; Kreplak, L; Tajmir-Riahi, H A

    2017-04-01

    Al cation may trigger protein structural changes such as aggregation and fibrillation, causing neurodegenerative diseases. We report the effect of Al cation on the solution structures of trypsin (try) and trypsin inhibitor (tryi), using thermodynamic analysis, UV-Visible, Fourier transform infrared (FTIR) spectroscopic methods and atomic force microscopy (AFM). Thermodynamic parameters showed Al-protein bindings occur via H-bonding and van der Waals contacts for trypsin and trypsin inhibitor. AFM showed that Al cations are able to force trypsin into larger or more robust aggregates than trypsin inhibitor, with trypsin 5±1 SE (n=52) proteins per aggregate and for trypsin inhibitor 8.3±0.7 SE (n=118). Thioflavin T test showed no major protein fibrillation in the presence of Al cation. Al complexation induced more alterations of trypsin inhibitor conformation than trypsin. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Recent Natural Corrosion Inhibitors for Mild Steel: An Overview

    Directory of Open Access Journals (Sweden)

    Marko Chigondo

    2016-01-01

    Full Text Available Traditionally, reduction of corrosion has been managed by various methods including cathodic protection, process control, reduction of the metal impurity content, and application of surface treatment techniques, as well as incorporation of suitable alloys. However, the use of corrosion inhibitors has proven to be the easiest and cheapest method for corrosion protection and prevention in acidic media. These inhibitors slow down the corrosion rate and thus prevent monetary losses due to metallic corrosion on industrial vessels, equipment, or surfaces. Inorganic and organic inhibitors are toxic and costly and thus recent focus has been turned to develop environmentally benign methods for corrosion retardation. Many researchers have recently focused on corrosion prevention methods using green inhibitors for mild steel in acidic solutions to mimic industrial processes. This paper provides an overview of types of corrosion, corrosion process, and mainly recent work done on the application of natural plant extracts as corrosion inhibitors for mild steel.

  18. Polyaspartic acid as a green corrosion inhibitor for carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Cui, R. [Department of Chemistry, Hebei Normal University, Shijiazhuang 050016 (China); Department of Chemistry and Materials Engineering, Changshu Institute of Technology, Changshu 215500 (China); Gu, N.; Li, C. [Department of Chemistry, Hebei Normal University, Shijiazhuang 050016 (China)

    2011-04-15

    The inhibitor effect of the environmentally friendly corrosion inhibitor polyaspartic acid (PASP) on the corrosion of carbon steel in 0.5 M H{sub 2}SO{sub 4} was investigated by weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). Polarization curve results clearly reveal the fact that PASP is a good anode-type inhibitor. EIS results confirm its corrosion inhibition ability. The inhibition efficiency increases with increasing PASP concentration, and the maximum inhibition efficiency was 80.33% at 10 C. SEM reveals that a protective film forms on the surface of the inhibited sample. The adsorption of this inhibitor is found to follow the Freundlich adsorption isotherm. A mechanism is proposed to explain the inhibitory action of the corrosion inhibitor. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Peptide inhibitors of botulinum neurotoxin by mRNA display

    International Nuclear Information System (INIS)

    Yiadom, Kwabena P.A.B.; Muhie, Seid; Yang, David C.H.

    2005-01-01

    Botulinum neurotoxins (BoNTs) are extremely toxic. The metalloproteases associated with the toxins cleave proteins essential for neurotransmitter secretion. Inhibitors of the metalloprotease are currently sought to control the toxicity of BoNTs. Toward that goal, we produced a synthetic cDNA for the expression and purification of the metalloprotease of BoNT/A in Escherichia coli as a biotin-ubiquitin fusion protein, and constructed a combinatorial peptide library to screen for BoNT/A light chain inhibitors using mRNA display. A protease assay was developed using immobilized intact SNAP-25 as the substrate. The new peptide inhibitors showed a 10-fold increase in affinity to BoNT/A light chain than the parent peptide. Interestingly, the sequences of the new peptide inhibitors showed abundant hydrophobic residues but few hydrophilic residues. The results suggest that mRNA display may provide a general approach in developing peptide inhibitors of BoNTs

  20. Potent Inhibitors against Newcastle Disease Virus Hemagglutinin-Neuraminidase.

    Science.gov (United States)

    Rota, Paola; La Rocca, Paolo; Piccoli, Marco; Montefiori, Marco; Cirillo, Federica; Olsen, Lars; Orioli, Marica; Allevi, Pietro; Anastasia, Luigi

    2018-02-06

    Neuraminidase activity is essential for the infection and propagation of paramyxoviruses, including human parainfluenza viruses (hPIVs) and the Newcastle disease virus (NDV). Thus, many inhibitors have been developed based on the 2-deoxy-2,3-didehydro-d-N-acetylneuraminic acid inhibitor (DANA) backbone. Along this line, herein we report a series of neuraminidase inhibitors, having C4 (p-toluenesulfonamido and azido substituents) and C5 (N-perfluorinated chains) modifications to the DANA backbone, resulting in compounds with 5- to 15-fold greater potency than the currently most active compound, the N-trifluoroacetyl derivative of DANA (FANA), toward the NDV hemagglutinin-neuraminidase (NDV-HN). Remarkably, these inhibitors were found to be essentially inactive against the human sialidase NEU3, which is present on the outer layer of the cell membrane and is highly affected by the current NDV inhibitor FANA. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Potential non-oncological applications of histone deacetylase inhibitors.

    Science.gov (United States)

    Ververis, Katherine; Karagiannis, Tom C

    2011-01-01

    Histone deacetylase inhibitors have emerged as a new class of anticancer therapeutic drugs. Their clinical utility in oncology stems from their intrinsic cytotoxic properties and combinatorial effects with other conventional cancer therapies. To date, the histone deacetylase inhibitors suberoylanilide hydroxamic acid (Vorinostat, Zolinza®) and depsipeptide (Romidepsin, Istodax®) have been approved by the US Food and Drug Administration for the treatment of refractory cutaneous T-cell lymphoma. Further, there are currently over 100 clinical trials involving the use of histone deacetylase inhibitors in a wide range of solid and hematological malignancies. The therapeutic potential of histone deacetylase inhibitors has also been investigated for numerous other diseases. For example, the cytotoxic properties of histone deacetylase inhibitors are currently being harnessed as a potential treatment for malaria, whereas the efficacy of these compounds for HIV relies on de-silencing latent virus. The anti-inflammatory properties of histone deacetylase inhibitors are the predominant mechanisms for other diseases, such as hepatitis, systemic lupus erythematosus and a wide range of neurodegenerative conditions. Additionally, histone deacetylase inhibitors have been shown to be efficacious in animal models of cardiac hypertrophy and asthma. Broad-spectrum histone deacetylase inhibitors are clinically available and have been used almost exclusively in preclinical systems to date. However, it is emerging that class- or isoform-specific compounds, which are becoming more readily available, may be more efficacious particularly for non-oncological applications. The aim of this review is to provide an overview of the effects and clinical potential of histone deacetylase inhibitors in various diseases. Apart from applications in oncology, the discussion is focused on the potential efficacy of histone deacetylase inhibitors for the treatment of neurodegenerative diseases, cardiac

  2. Organization of the gene coding for human protein C inhibitor (plasminogen activator inhibitor-3). Assignment of the gene to chromosome 14

    NARCIS (Netherlands)

    Meijers, J. C.; Chung, D. W.

    1991-01-01

    Protein C inhibitor (plasminogen activator inhibitor-3) is a plasma glycoprotein and a member of the serine proteinase inhibitor superfamily. In the present study, the human gene for protein C inhibitor was isolated and characterized from three independent phage that contained overlapping inserts

  3. Classification of Cytochrome P450 1A2 Inhibitors and Non-Inhibitors by Machine Learning Techniques

    DEFF Research Database (Denmark)

    Vasanthanathan, Poongavanam; Taboureau, Olivier; Oostenbrink, Chris

    2009-01-01

    of CYP1A2 inhibitors and non-inhibitors. Training and test sets consisted of about 400 and 7000 compounds, respectively. Various machine learning techniques, like binary QSAR, support vector machine (SVM), random forest, kappa nearest neighbors (kNN), and decision tree methods were used to develop...

  4. The effects of residual platelets in plasma on plasminogen activator inhibitor-1 and plasminogen activator inhibitor-1-related assays

    NARCIS (Netherlands)

    M. Pieters (Marlien); S.A. Barnard (Sunelle A.); D.T. Loots (Du Toit); D.C. Rijken (Dingeman)

    2017-01-01

    textabstractDue to controversial evidence in the literature pertaining to the activity of plasminogen activator inhibitor-1 in platelets, we examined the effects of residual platelets present in plasma (a potential pre-analytical variable) on various plasminogen activator inhibitor-1 and plasminogen

  5. Nonnucleoside Reverse-transcriptase Inhibitor- vs Ritonavir-boosted Protease Inhibitor-based Regimens for Initial Treatment of HIV Infection

    DEFF Research Database (Denmark)

    Borges, Álvaro H; Lundh, Andreas; Tendal, Britta

    2016-01-01

    BACKGROUND: Previous studies suggest that nonnucleoside reverse-transcriptase inhibitors (NNRTIs) cause faster virologic suppression, while ritonavir-boosted protease inhibitors (PI/r) recover more CD4 cells. However, individual trials have not been powered to compare clinical outcomes. METHODS: ...

  6. Retro-binding thrombin active site inhibitors: identification of an orally active inhibitor of thrombin catalytic activity.

    Science.gov (United States)

    Iwanowicz, Edwin J; Kimball, S David; Lin, James; Lau, Wan; Han, W-C; Wang, Tammy C; Roberts, Daniel G M; Schumacher, W A; Ogletree, Martin L; Seiler, Steven M

    2002-11-04

    A series of retro-binding inhibitors of human alpha-thrombin was prepared to elucidate structure-activity relationships (SAR) and optimize in vivo performance. Compounds 9 and 11, orally active inhibitors of thrombin catalytic activity, were identified to be efficacious in a thrombin-induced lethality model in mice.

  7. Additives as corrosion inhibitors in reinforced concrete

    International Nuclear Information System (INIS)

    Venegas, Ricardo; Vera, Rosa; Carvajal, Ana Maria; Villarroel, Maria; Vera, Enrique; Ortiz, Cesar

    2008-01-01

    This work studies the behavior of two additives as inhibitors of corrosion in reinforced concrete. The presence of Microsilica, a physical inhibitor, in the mixture decreases pore size in structures and improves compression. Calcium Nitrite, a chemical inhibitor, is an oxidizing agent and allows a more homogenous film to form over the steel that becomes more resistant to attacks from aggressive ions like anion chloride and others. Three pairs of concrete test pieces were used without additives and with additives with a/c ration of 0.55. The samples were exposed to an accelerated attack of chlorides, submerging them in a 4.27 M solution of NaCl for 24 hours and then drying them at room temperature for another 24 hours, completing a cycle every 48 hours. The tests were carried out at 1 cycle and 5 cycles of partial moistening and drying. The steel corrosion was evaluated with corrosion potential measurements. Conductivity, pH, chlorides and sulfate profiles were defined depending on the depth of the concrete. The composition of the corrosion products was determined using X-ray diffraction and the morphology of the film by scanning electron microscopy. The results show that for 1 test cycle, the corrosion potential of the steel in the sample with calcium nitrite was -54mV, which was a higher value than that measured in the sample with microsilica (-217.3mV) and without an additive (-159.1mV), corroborating its inhibitory power. The content of the free chlorides in the sample with micros ice allows greater capillary suction by adding high amounts of chloride to the structure (2.6% on the outside up to 2.20% near the steel); while the test pieces with calcium nitrite and without an additive had concentrations lower than 2% in all the evaluated points. After five cycles of exposing the samples to the saline solution the behavior is inverted. The measures of conductivity agreed with the previous results. Meanwhile, the pH of the solutions obtained from the powder from the

  8. Urinary trypsin inhibitor - an experimental and clinical study

    International Nuclear Information System (INIS)

    Berling, B.M.

    1991-01-01

    The urinary trypsin inhibitor (UTI) is an acid stable proteinase inhibitor present in blood and urine. It was purified from urine using affinity chromatography, ion exchange chromatography and gel filtration. Two forms of UTI were present in urine, A and B. A radioimmunoassay for measurement of UTI in urine and plasma was performed. The normal level of UTI in plasma and serum was about 2 mg/l. The normal excretion in urine was about 8 mg per 24 hours. The plasma and urine levels of UTI were studied in patients with acute pancreatitis and in patients undergoing cholecystectomy. Uremic patients had a marked increase of UTI in plasma compatible with decreased glomerular filtration. In samples from healthy persons as well as from patients only inhibitor A was found. Inhibitor B has recently been renamed bikunin because of its two Kunitz-type inhibiting domains. Inhibitor A might be called tetrakunin. Radioactively labeled UTI (inhibitor A) was injected intravenously in three male volunteers. The plasma half-life of 125 I UTI was 2 hours. Free biologically active inhibitor was found in the urine during the first four hours after injection. The organ distribution of intravenously injected 125 I UTI was studied in rats. Fifteen minutes after injection the major part of the radioactivity was found in the kidneys, suggesting that the kidneys are the primary site of UTI metabolism. Using immunohistochemical techniques UTI was found in the proximal tubules of the normal human kidney further indicating the tubular reabsorption and methabolisms of UTI

  9. A novel class of small molecule inhibitors of HDAC6.

    Science.gov (United States)

    Inks, Elizabeth S; Josey, Benjamin J; Jesinkey, Sean R; Chou, C James

    2012-02-17

    Histone deacetylases (HDACs) are a family of enzymes that play significant roles in numerous biological processes and diseases. HDACs are best known for their repressive influence on gene transcription through histone deacetylation. Mapping of nonhistone acetylated proteins and acetylation-modifying enzymes involved in various cellular pathways has shown protein acetylation/deacetylation also plays key roles in a variety of cellular processes including RNA splicing, nuclear transport, and cytoskeletal remodeling. Studies of HDACs have accelerated due to the availability of small molecule HDAC inhibitors, most of which contain a canonical hydroxamic acid or benzamide that chelates the metal catalytic site. To increase the pool of unique and novel HDAC inhibitor pharmacophores, a pharmacological active compound screen was performed. Several unique HDAC inhibitor pharmacophores were identified in vitro. One class of novel HDAC inhibitors, with a central naphthoquinone structure, displayed a selective inhibition profile against HDAC6. Here we present the results of a unique class of HDAC6 inhibitors identified using this compound library screen. In addition, we demonstrated that treatment of human acute myeloid leukemia cell line MV4-11 with the selective HDAC6 inhibitors decreases levels of mutant FLT-3 and constitutively active STAT5 and attenuates Erk phosphorylation, all of which are associated with the inhibitor's selective toxicity against leukemia.

  10. A novel method for screening the glutathione transferase inhibitors

    Directory of Open Access Journals (Sweden)

    Węgrzyn Grzegorz

    2009-03-01

    Full Text Available Abstract Background Glutathione transferases (GSTs belong to the family of Phase II detoxification enzymes. GSTs catalyze the conjugation of glutathione to different endogenous and exogenous electrophilic compounds. Over-expression of GSTs was demonstrated in a number of different human cancer cells. It has been found that the resistance to many anticancer chemotherapeutics is directly correlated with the over-expression of GSTs. Therefore, it appears to be important to find new GST inhibitors to prevent the resistance of cells to anticancer drugs. In order to search for glutathione transferase (GST inhibitors, a novel method was designed. Results Our results showed that two fragments of GST, named F1 peptide (GYWKIKGLV and F2 peptide (KWRNKKFELGLEFPNL, can significantly inhibit the GST activity. When these two fragments were compared with several known potent GST inhibitors, the order of inhibition efficiency (measured in reactions with 2,4-dinitrochlorobenzene (CDNB and glutathione as substrates was determined as follows: tannic acid > cibacron blue > F2 peptide > hematin > F1 peptide > ethacrynic acid. Moreover, the F1 peptide appeared to be a noncompetitive inhibitor of the GST-catalyzed reaction, while the F2 peptide was determined as a competitive inhibitor of this reaction. Conclusion It appears that the F2 peptide can be used as a new potent specific GST inhibitor. It is proposed that the novel method, described in this report, might be useful for screening the inhibitors of not only GST but also other enzymes.

  11. Indanones as high-potency reversible inhibitors of monoamine oxidase.

    Science.gov (United States)

    Mostert, Samantha; Petzer, Anél; Petzer, Jacobus P

    2015-05-01

    Recent reports document that α-tetralone (3,4-dihydro-2H-naphthalen-1-one) is an appropriate scaffold for the design of high-potency monoamine oxidase (MAO) inhibitors. Based on the structural similarity between α-tetralone and 1-indanone, the present study involved synthesis of 34 1-indanone and related indane derivatives as potential inhibitors of recombinant human MAO-A and MAO-B. The results show that C6-substituted indanones are particularly potent and selective MAO-B inhibitors, with IC50 values ranging from 0.001 to 0.030 μM. C5-Substituted indanone and indane derivatives are comparatively weaker MAO-B inhibitors. Although the 1-indanone and indane derivatives are selective inhibitors of the MAO-B isoform, a number of homologues are also potent MAO-A inhibitors, with three homologues possessing IC50 values 1-indanone as a reversible MAO inhibitor with a competitive mode of inhibition. It may be concluded that 1-indanones are promising leads for the design of therapies for neurodegenerative and neuropsychiatric disorders such as Parkinson's disease and depression. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Synthesis of tritium labeled renin inhibitor ditekiren

    International Nuclear Information System (INIS)

    Hsi, R.S.P.; Stolle, W.T.; Bundy, G.L.

    1994-01-01

    In the search for a radioactive form of the peptidomimetic renin inhibitor, ditekiren, with a metabolically suitable radiolabel for conducting drug disposition studies, we prepared [ 3 H]ditekiren with tritium labels in the N-methyl-histidine moiety and in the leu-val alcohol transition-state insert. [His- 3 H]ditekiren was obtained by first introducing two iodine substituents into the N-methyl-histidine moiety of the parent drug, followed by catalytic hydrodehalogenation with tritium gas. Administration of this labeled drug to monkeys, however, resulted in prolonged retention of radioactivity in the test animals, even though little or no tritiated water was detected in urine. The results, together with similar earlier findings after administration of [ 3 H]ditekiren labeled in the proline moiety of the drug, led us to synthesize [ 3 H]ditekiren labeled in the ''unnatural'' leu-val alcohol (LVA) portion of the molecule. The tritium label in [LVA- 3 H]ditekiren was found to be metabolically suitable for conducting drug disposition studies, with no liability for tritiated water production or prolonged retention of radioactivity in tissues of test animals. (author)

  13. Aromatase inhibitors in stimulated IVF cycles

    Directory of Open Access Journals (Sweden)

    Tournaye Herman

    2011-06-01

    Full Text Available Abstract Aromatase inhibitors have been introduced as a new treatment modality that could challenge clomiphene citrate as an ovulation induction regiment in patients with PCOS. Although several randomized trials have been conducted regarding their use as ovulation induction agents, only few trials are available regarding their efficacy in IVF stimulated cycles. Current available evidence support that letrozole may have a promising role in stimulated IVF cycles, either when administered during the follicular phase for ovarian stimulation. Especially for women with poor ovarian response, letrozole appears to have the potential to increase clinical pregnancy rates when combined with gonadotropins, whereas at the same time reduces the total gonadotropin dose required for ovarian stimulation. However, given that in all of the trials letrozole has been administered in GnRH antagonist cycles, it is intriguing to test in the future how it may perform when used in GnRH agonist cycles. Finally administration of letrozole during luteal phase in IVF cycles offers another treatment modality for patients at high risk for OHSS taking into account that it drastically reduces estradiol levels

  14. Immunomodulatory effects of histone deacetylase inhibitors.

    Science.gov (United States)

    Licciardi, P V; Ververis, K; Tang, M L; El-Osta, A; Karagiannis, T C

    2013-05-01

    Histone deacetylase inhibitors (HDACi) have emerged as a new generation of anticancer therapeutics. The classical broad-spectrum HDACi typically alter the cell cycle distribution and induce cell death, apoptosis and differentiation in malignant and transformed cells. This provides the basis for the clinical potential of HDACi in cancer therapy. Currently two compounds, suberoylanilide hydroxamic acid (SAHA, Vorinostat, Zolinza™) and depsipeptide (Romidepsin, Istodax™) have been approved for by the US Food and Drug Administration for the treatment of refractory cutaneous T-cell lymphoma. Apart from clinical application in oncology, HDACi have also been investigated as potential therapeutics for various pathologies including those of the central nervous system (such as Huntington's disease and multiple sclerosis), cardiac conditions (particularly hypertrophy), arthritis and malaria. Further, evidence is accumulating for potent immunomodulatory effects of classical HDACi which is the focus of this review. We review the antiinflammatory effects of HDACi and in particular findings implicating regulation of the innate and adaptive immune systems by HDAC enzymes. The recent findings highlighting the immunomodulatory function of HDAC11 which relates to balancing immune activation versus tolerance are also discussed.

  15. Inhibitors of Ras-SOS Interactions.

    Science.gov (United States)

    Lu, Shaoyong; Jang, Hyunbum; Zhang, Jian; Nussinov, Ruth

    2016-04-19

    Activating Ras mutations are found in about 30 % of human cancers. Ras activation is regulated by guanine nucleotide exchange factors, such as the son of sevenless (SOS), which form protein-protein interactions (PPIs) with Ras and catalyze the exchange of GDP by GTP. This is the rate-limiting step in Ras activation. However, Ras surfaces lack any evident suitable pockets where a molecule might bind tightly, rendering Ras proteins still 'undruggable' for over 30 years. Among the alternative approaches is the design of inhibitors that target the Ras-SOS PPI interface, a strategy that is gaining increasing recognition for treating Ras mutant cancers. Herein we focus on data that has accumulated over the past few years pertaining to the design of small-molecule modulators or peptide mimetics aimed at the interface of the Ras-SOS PPI. We emphasize, however, that even if such Ras-SOS therapeutics are potent, drug resistance may emerge. To counteract this development, we propose "pathway drug cocktails", that is, drug combinations aimed at parallel (or compensatory) pathways. A repertoire of classified cancer, cell/tissue, and pathway/protein combinations would be beneficial toward this goal. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Potential Expanded Indications for Neprilysin Inhibitors

    Science.gov (United States)

    Riddell, Elizabeth; Vader, Justin M.

    2017-01-01

    Purpose of review The goal of this article is to review potential expanded indications for neprilysin inhibitors. This article reviews the rationale and design for ongoing and future trials of sacubitril/valsartan in cardiovascular and non-cardiovascular disease. Recent findings Randomized trial data are lacking for use of sacubitril/valsartan in acute heart failure and advanced heart failure. Mechanistic data from animal studies suggest a role for neprilysin inhibition in the treatment of post-myocardial infarction systolic dysfunction and heart failure with preserved ejection fraction. Beyond the cardiovascular system, renal and neurological function may be impacted by neprilysin inhibition. Forthcoming randomized trials will address the clinical impact of sacubitril/valsartan on these conditions. Summary Neprolysin inhibition with sacubitril/valsartan offers a new therapeutic strategy with a broad range of potential therapeutic actions. In PARADIGM-HF, the combination of neprolysin and RAAS inhibition was proven to be superior to enalapril for patients with stable NYHA class II–III heart failure and reduced left ventricular ejection fraction. Preliminary data suggests it may also have a role in other cardiovascular and non-cardiovascular disease. Several ongoing and planned studies will determine the extent of its benefit for these other indications. PMID:28281174

  17. Enzymes and Inhibitors in Neonicotinoid Insecticide Metabolism

    Science.gov (United States)

    Shi, Xueyan; Dick, Ryan A.; Ford, Kevin A.; Casida, John E.

    2009-01-01

    Neonicotinoid insecticide metabolism involves considerable substrate specificity and regioselectivity of the relevant CYP450, aldehyde oxidase, and phase II enzymes. Human CYP450 recombinant enzymes carry out the following conversions: CYP3A4, 2C19 and 2B6 for thiamethoxam (TMX) to clothianidin (CLO); 3A4, 2C19 and 2A6 for CLO to desmethyl-CLO; 2C19 for TMX to desmethyl-TMX. Human liver aldehyde oxidase reduces the nitro substituent of CLO to nitroso much more rapidly than that of TMX. Imidacloprid (IMI), CLO and several of their metabolites do not give detectable N-glucuronides but 5-hydroxy-IMI, 4,5-diol-IMI and 4-hydroxy-thiacloprid are converted to O-glucuronides in vitro with mouse liver microsomes and UDP-glucuronic acid or in vivo in mice. Mouse liver cytosol with S-adenosylmethionine converts desmethyl-CLO to CLO but not desmethyl-TMX to TMX. Two organophosphorus CYP450 inhibitors partially block IMI, thiacloprid and CLO metabolism in vivo in mice, elevating the brain and liver levels of the parent compounds while reducing amounts of the hydroxylated metabolites. PMID:19391582

  18. ADPRT inhibitors and hyperthermia as radiosensitizers

    International Nuclear Information System (INIS)

    Jonsson, G.G.

    1985-01-01

    Hyperthermia given in combination with gamma radiation has given considerable improvement in the therapeutic results for treatment of malignant tumors. The mechanism behind the hyperthermia effect is probably operative at the tissue level as well as at the molecular level. The metabolism of NAD + in relation to the activity of the chromosomal enzyme ADP-ribosyl transferase (ADPRT) has been studied as a possible molecular mechanism for this effect. The ADPRT activity was measured after radiosensitization with both hyperthermia and nicotinamide, which is a potent inhibitor of ADPRT. The results indicate that hyperthermia can improve the effect of radiotherapy by reducing the supply of NAD + , which is a co-substrate for ADPRT, while nicotinamide functions as a radiosensitizing agent by direct inhibition of the enzyme. The hypothesis is discussed in the thesis where inhibition of ADPRT might increase the radiosensitivity because the radiation-induced DNA damage can not be repaired with normal efficiency. The function of nicotinamide as a radiosensitizer was verified by studies on C3H mice with transplanted spontaneous mammary tumors. Because nicotinamide is not toxic, it seems quite attractive to test this vitamin as a radiosensitizing agent against human tumors. (251 refs.) (author)

  19. Efflux inhibitor suppresses Streptococcus mutans virulence properties.

    Science.gov (United States)

    Zeng, Huihui; Liu, Jia; Ling, Junqi

    2017-04-01

    It is well established that efflux pumps play important roles in bacterial pathogenicity and efflux inhibitors (EIs) have been proved to be effective in suppressing bacterial virulence properties. However, little is known regarding the EI of Streptococcus mutans, a well-known caries-inducing bacterium. In this study, we identified the EI of S. mutans through ethidium bromide efflux assay and investigated how EI affected S. mutans virulence regarding the cariogenicity and stress response. Results indicated that reserpine, the identified EI, suppressed acid tolerance, mutacin production and transformation efficiency of S. mutans, and modified biofilm architecture and extracellular polysaccharide distribution. Suppressed glycosyltransferase activity was also noted after reserpine exposure. The data from quantitative real-time-PCR demonstrated that reserpine significantly altered the expression profile of quorum-sensing and virulence-associated genes. These findings suggest that reserpine represents a promising adjunct anticariogenic agent in that it suppresses virulence properties of S. mutans. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. In silico development of new acetylcholinesterase inhibitors.

    Science.gov (United States)

    Pascoini, A L; Federico, L B; Arêas, A L F; Verde, B A; Freitas, P G; Camps, I

    2018-04-19

    In this work, we made use of fragment-based drug design (FBDD) and de novo design to obtain more powerful acetylcholinesterase (AChE) inhibitors. AChE is associated with Alzheimer's disease (AD). It was found that the cholinergic pathways in the cerebral cortex are compromised in AD and the accompanying cholinergic deficiency contributes to the cognitive deterioration of AD patients. In the FBDD approach, fragments are docked into the active site of the protein. As fragments are molecular groups with a low number of atoms, it is possible to study their interaction with localized amino acids. Once the interactions are measured, the fragments are organized by affinity and then linked together to form new molecules with a high degree of interaction with the active site. In the other approach, we used the de novo design technique starting from reference drugs used in the AD treatment. These drugs were broken into fragments (seeds). In the growing strategy, fragments were added to each seed, growing new molecules. In the linking strategy, two or more separated seeds were linked with different fragments. Both strategies combined produced a library of more than 2 million compounds. This library was filtered using absorption, distribution, metabolism, and excretion properties. The resulting library with around six thousand compounds was filtered again. In this case, structures with Tanimoto coefficients >.85 were discarded. The final library with 1500 compounds was submitted to docking studies. As a result, 10 compounds with better interaction energy than the reference drugs were obtained.

  1. Reverse transcriptase inhibitors as potential colorectal microbicides.

    Science.gov (United States)

    Herrera, Carolina; Cranage, Martin; McGowan, Ian; Anton, Peter; Shattock, Robin J

    2009-05-01

    We investigated whether reverse transcriptase (RT) inhibitors (RTI) can be combined to inhibit human immunodeficiency virus type 1 (HIV-1) infection of colorectal tissue ex vivo as part of a strategy to develop an effective rectal microbicide. The nucleotide RTI (NRTI) PMPA (tenofovir) and two nonnucleoside RTI (NNRTI), UC-781 and TMC120 (dapivirine), were evaluated. Each compound inhibited the replication of the HIV isolates tested in TZM-bl cells, peripheral blood mononuclear cells, and colorectal explants. Dual combinations of the three compounds, either NRTI-NNRTI or NNRTI-NNRTI combinations, were more active than any of the individual compounds in both cellular and tissue models. Combinations were key to inhibiting infection by NRTI- and NNRTI-resistant isolates in all models tested. Moreover, we found that the replication capacities of HIV-1 isolates in colorectal explants were affected by single point mutations in RT that confer resistance to RTI. These data demonstrate that colorectal explants can be used to screen compounds for potential efficacy as part of a combination microbicide and to determine the mucosal fitness of RTI-resistant isolates. These findings may have important implications for the rational design of effective rectal microbicides.

  2. Natural sesquiterpen lactones as acetylcholinesterase inhibitors

    Directory of Open Access Journals (Sweden)

    HOMA HAJIMEHDIPOOR

    2014-06-01

    Full Text Available Background and the purpose of the study: The amount of elder people who suffer from Alzheimer disease is continuously increasing every year. Cholinesterase inhibitors have shown to be effective in alleviating the symptoms of the disease, thus opening a field of research for these treatments. Herbal products, owning a reputation as effective agents in many biological studies are now drawing attention for inhibiting acetylcholinesterase, in other words, Alzheimer disease. In the present study, the ability of three sesquiterpene lactones from Inula oculus-christi and I. aucheriana to inhibit AChE has been evaluated through Ellman assay.Materials and Methods: Gaillardin and pulchellin C were obtained from I. oculus-christi and britannin from I. aucheriana by chromatographic methods. They were dissolved in methanol in concentration of 3 mg/mL and the AChEI activity of the compounds was determined by Ellman method using Acethylthiocholine iodide as the substrate and 5, 5′-dithiobis-2-nitrobenzoic acid as the reagent, in 96-well plates at 405 nm.Results: AChEI activity of the examined compounds was obtained as 67.0, 25.2 and 10.9% in concentration of 300 µg/L for gaillardin, britannin and pulchellin C, respectively.Conclusion: Among the three sesquiterpene lactones, gaillardin with 67% inhibition of AChE could be considered a good candidate for future Alzheimer studies.

  3. Suppression of Coronavirus Replication by Cyclophilin Inhibitors

    Directory of Open Access Journals (Sweden)

    Takashi Sasaki

    2013-05-01

    Full Text Available Coronaviruses infect a variety of mammalian and avian species and cause serious diseases in humans, cats, mice, and birds in the form of severe acute respiratory syndrome (SARS, feline infectious peritonitis (FIP, mouse hepatitis, and avian infectious bronchitis, respectively. No effective vaccine or treatment has been developed for SARS-coronavirus or FIP virus, both of which cause lethal diseases. It has been reported that a cyclophilin inhibitor, cyclosporin A (CsA, could inhibit the replication of coronaviruses. CsA is a well-known immunosuppressive drug that binds to cellular cyclophilins to inhibit calcineurin, a calcium-calmodulin-activated serine/threonine-specific phosphatase. The inhibition of calcineurin blocks the translocation of nuclear factor of activated T cells from the cytosol into the nucleus, thus preventing the transcription of genes encoding cytokines such as interleukin-2. Cyclophilins are peptidyl-prolyl isomerases with physiological functions that have been described for many years to include chaperone and foldase activities. Also, many viruses require cyclophilins for replication; these include human immunodeficiency virus, vesicular stomatitis virus, and hepatitis C virus. However, the molecular mechanisms leading to the suppression of viral replication differ for different viruses. This review describes the suppressive effects of CsA on coronavirus replication.

  4. Clinically Applicable Inhibitors Impacting Genome Stability.

    Science.gov (United States)

    Prakash, Anu; Garcia-Moreno, Juan F; Brown, James A L; Bourke, Emer

    2018-05-13

    Advances in technology have facilitated the molecular profiling (genomic and transcriptomic) of tumours, and has led to improved stratification of patients and the individualisation of treatment regimes. To fully realize the potential of truly personalised treatment options, we need targeted therapies that precisely disrupt the compensatory pathways identified by profiling which allow tumours to survive or gain resistance to treatments. Here, we discuss recent advances in novel therapies that impact the genome (chromosomes and chromatin), pathways targeted and the stage of the pathways targeted. The current state of research will be discussed, with a focus on compounds that have advanced into trials (clinical and pre-clinical). We will discuss inhibitors of specific DNA damage responses and other genome stability pathways, including those in development, which are likely to synergistically combine with current therapeutic options. Tumour profiling data, combined with the knowledge of new treatments that affect the regulation of essential tumour signalling pathways, is revealing fundamental insights into cancer progression and resistance mechanisms. This is the forefront of the next evolution of advanced oncology medicine that will ultimately lead to improved survival and may, one day, result in many cancers becoming chronic conditions, rather than fatal diseases.

  5. SGLT2 Inhibitors in Diabetes Mellitus Treatment.

    Science.gov (United States)

    Rosas-Guzman, Juan; Rosas-Saucedo, Juan; Romero-Garcia, Alma R J

    2017-01-01

    Type 2 Diabetes Mellitus (T2DM) is a chronic illness with high prevalence in Mexico, Latin- America, and the world and is associated to high morbidity, disability, and mortality rate, especially in developing countries. T2DM physiopathology is very complex; insulin resistance in the muscle, liver, and adipose tissue, a reduction in the production of incretins (mainly GLP-1) in the intestine, increased glucagon synthesis, an insufficient response of insulin generation, and increased glucose reabsorption in the kidney lead all together to an hyperglycemic state, which has been closely associated with the development of micro and macrovascular complications. Sodium Glucose Linked Transporter 2 inhibitors (SGLT2i) are the most recent therapeutic class available for treating T2DM. SGLT2i central effect is a glycosuric action, and they can reverse the deleterious effect of tubular reabsorption of glucose in the diabetic patient resulting in greater hyperglycemia. Because their mechanism of action is completely different to current drugs, they can be considered as monotherapy or in combination with any other oral or parenteral medication, including different types of insulin or its analogues. This therapeutic synergy accomplishes a greater percentage of patients achieving glycemic control goals. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  6. Interpreting clinical assays for histone deacetylase inhibitors

    International Nuclear Information System (INIS)

    Martinet, Nadine; Bertrand, Philippe

    2011-01-01

    As opposed to genetics, dealing with gene expressions by direct DNA sequence modifications, the term epigenetics applies to all the external influences that target the chromatin structure of cells with impact on gene expression unrelated to the sequence coding of DNA itself. In normal cells, epigenetics modulates gene expression through all development steps. When “imprinted” early by the environment, epigenetic changes influence the organism at an early stage and can be transmitted to the progeny. Together with DNA sequence alterations, DNA aberrant cytosine methylation and microRNA deregulation, epigenetic modifications participate in the malignant transformation of cells. Their reversible nature has led to the emergence of the promising field of epigenetic therapy. The efforts made to inhibit in particular the epigenetic enzyme family called histone deacetylases (HDACs) are described. HDAC inhibitors (HDACi) have been proposed as a viable clinical therapeutic approach for the treatment of leukemia and solid tumors, but also to a lesser degree for noncancerous diseases. Three epigenetic drugs are already arriving at the patient’s bedside, and more than 100 clinical assays for HDACi are registered on the National Cancer Institute website. They explore the eventual additive benefits of combined therapies. In the context of the pleiotropic effects of HDAC isoforms, more specific HDACi and more informative screening tests are being developed for the benefit of the patients

  7. A novel small molecule inhibitor of hepatitis C virus entry.

    Directory of Open Access Journals (Sweden)

    Carl J Baldick

    Full Text Available Small molecule inhibitors of hepatitis C virus (HCV are being developed to complement or replace treatments with pegylated interferons and ribavirin, which have poor response rates and significant side effects. Resistance to these inhibitors emerges rapidly in the clinic, suggesting that successful therapy will involve combination therapy with multiple inhibitors of different targets. The entry process of HCV into hepatocytes represents another series of potential targets for therapeutic intervention, involving viral structural proteins that have not been extensively explored due to experimental limitations. To discover HCV entry inhibitors, we utilized HCV pseudoparticles (HCVpp incorporating E1-E2 envelope proteins from a genotype 1b clinical isolate. Screening of a small molecule library identified a potent HCV-specific triazine inhibitor, EI-1. A series of HCVpp with E1-E2 sequences from various HCV isolates was used to show activity against all genotype 1a and 1b HCVpp tested, with median EC50 values of 0.134 and 0.027 µM, respectively. Time-of-addition experiments demonstrated a block in HCVpp entry, downstream of initial attachment to the cell surface, and prior to or concomitant with bafilomycin inhibition of endosomal acidification. EI-1 was equally active against cell-culture adapted HCV (HCVcc, blocking both cell-free entry and cell-to-cell transmission of virus. HCVcc with high-level resistance to EI-1 was selected by sequential passage in the presence of inhibitor, and resistance was shown to be conferred by changes to residue 719 in the carboxy-terminal transmembrane anchor region of E2, implicating this envelope protein in EI-1 susceptibility. Combinations of EI-1 with interferon, or inhibitors of NS3 or NS5A, resulted in additive to synergistic activity. These results suggest that inhibitors of HCV entry could be added to replication inhibitors and interferons already in development.

  8. Inhibitor development and mortality in non-severe hemophilia A.

    Science.gov (United States)

    Eckhardt, C L; Loomans, J I; van Velzen, A S; Peters, M; Mauser-Bunschoten, E P; Schwaab, R; Mazzucconi, M G; Tagliaferri, A; Siegmund, B; Reitter-Pfoertner, S E; van der Bom, J G; Fijnvandraat, K

    2015-07-01

    The life expectancy of non-severe hemophilia A (HA) patients equals the life expectancy of the non-hemophilic population. However, data on the effect of inhibitor development on mortality and on hemophilia-related causes of death are scarce. The development of neutralizing factor VIII antibodies in non-severe HA patients may dramatically change their clinical outcome due to severe bleeding complications. We assessed the association between the occurrence of inhibitors and mortality in patients with non-severe HA. In this retrospective cohort study, clinical data and vital status were collected for 2709 non-severe HA patients (107 with inhibitors) who were treated between 1980 and 2011 in 34 European and Australian centers. Mortality rates for patients with and without inhibitors were compared. During 64,200 patient-years of follow-up, 148 patients died (mortality rate, 2.30 per 1000 person-years; 95% confidence interval (CI), 1.96-2.70) at a median age of 64 years (interquartile range [IQR], 49-76). In 62 patients (42%) the cause of death was hemophilia related. Sixteen inhibitor patients died at a median age of 71 years (IQR, 60-81). In ten patients the inhibitor was present at time of death; seven of them died of severe bleeding complications. The all-cause mortality rate in inhibitor patients was > 5 times increased compared with that for those without inhibitors (age-adjusted mortality rate ratio, 5.6). Inhibitor development in non-severe hemophilia is associated with increased mortality. High rates of hemophilia-related mortality in this study indicate that non-severe hemophilia is not mild at all and stress the importance of close follow-up for these patients. © 2015 International Society on Thrombosis and Haemostasis.

  9. Janus Associated Kinases Inhibitors in the Pharmacological Thera

    Directory of Open Access Journals (Sweden)

    Daniela Santos1

    2017-01-01

    Full Text Available Janus associated kinases inhibitors are a new strategy for the treatment of different clinical conditions like immunologic, inflammatory and oncology disorders. The aim of this study was to perform a review of all Janus associated kinases inhibitors available in national and international pharmaceutical market, their therapeutic indications and adverse effects, and the potential indications for investigation of those already available in the pharmaceutical market. It was also performed a review of the main new Janus associated kinases inhibitors that are still in clinical research. A literature review was conducted by consulting the summary of product characteristics of Janus associated kinases inhibitors available in the pharmaceutical market and a research in the bibliographic database PubMed using the terms «JAK inhibitors», «Janus associated kinases inhibitors» and «Janus kinases inhibitors». Ninety-five publications were included in the present review, published from January 2014 to January 2015. Drug databases of the European Medicines Agency and United States Food and Drug Administration were also consulted to search for Janus associated kinases inhibitors authorized in clinical practice. Currently, ruxolitinib and tofacitinib are available in the pharmaceutical market and oclatinib is approved as a veterinary medicinal product. Both drugs approved for human use have major adverse effects at hematological and immunological levels, which enhance the importance of the pharmacist’s role in the monitoring of patients involved in these treatments. However, several molecules are in pre-clinical and clinical studies trying to prove its potential in the treatment of several immunologic, inflammatory and oncology disorders. Thus, it is still necessary to deepen the knowledge in this area in order to overcome the risks of therapy with these agents. These risks weighed against the benefits of its clinical use have compromised the progress of

  10. New synthetic thrombin inhibitors: molecular design and experimental verification.

    Science.gov (United States)

    Sinauridze, Elena I; Romanov, Alexey N; Gribkova, Irina V; Kondakova, Olga A; Surov, Stepan S; Gorbatenko, Aleksander S; Butylin, Andrey A; Monakov, Mikhail Yu; Bogolyubov, Alexey A; Kuznetsov, Yuryi V; Sulimov, Vladimir B; Ataullakhanov, Fazoyl I

    2011-01-01

    The development of new anticoagulants is an important goal for the improvement of thromboses treatments. The design, synthesis and experimental testing of new safe and effective small molecule direct thrombin inhibitors for intravenous administration. Computer-aided molecular design of new thrombin inhibitors was performed using our original docking program SOL, which is based on the genetic algorithm of global energy minimization in the framework of a Merck Molecular Force Field. This program takes into account the effects of solvent. The designed molecules with the best scoring functions (calculated binding energies) were synthesized and their thrombin inhibitory activity evaluated experimentally in vitro using a chromogenic substrate in a buffer system and using a thrombin generation test in isolated plasma and in vivo using the newly developed model of hemodilution-induced hypercoagulation in rats. The acute toxicities of the most promising new thrombin inhibitors were evaluated in mice, and their stabilities in aqueous solutions were measured. New compounds that are both effective direct thrombin inhibitors (the best K(I) was 50) in the thrombin generation assay of approximately 100 nM) were discovered. These compounds contain one of the following new residues as the basic fragment: isothiuronium, 4-aminopyridinium, or 2-aminothiazolinium. LD(50) values for the best new inhibitors ranged from 166.7 to >1111.1 mg/kg. A plasma-substituting solution supplemented with one of the new inhibitors prevented hypercoagulation in the rat model of hemodilution-induced hypercoagulation. Activities of the best new inhibitors in physiological saline (1 µM solutions) were stable after sterilization by autoclaving, and the inhibitors remained stable at long-term storage over more than 1.5 years at room temperature and at 4°C. The high efficacy, stability and low acute toxicity reveal that the inhibitors that were developed may be promising for potential medical applications.

  11. mTOR inhibitors alone and in combination with JAK2 inhibitors effectively inhibit cells of myeloproliferative neoplasms.

    Directory of Open Access Journals (Sweden)

    Costanza Bogani

    Full Text Available BACKGROUND: Dysregulated signaling of the JAK/STAT pathway is a common feature of chronic myeloproliferative neoplasms (MPN, usually associated with JAK2V617F mutation. Recent clinical trials with JAK2 inhibitors showed significant improvements in splenomegaly and constitutional symptoms in patients with myelofibrosis but meaningful molecular responses were not documented. Accordingly, there remains a need for exploring new treatment strategies of MPN. A potential additional target for treatment is represented by the PI3K/AKT/mammalian target of rapamycin (mTOR pathway that has been found constitutively activated in MPN cells; proof-of-evidence of efficacy of the mTOR inhibitor RAD001 has been obtained recently in a Phase I/II trial in patients with myelofibrosis. The aim of the study was to characterize the effects in vitro of mTOR inhibitors, used alone and in combination with JAK2 inhibitors, against MPN cells. FINDINGS: Mouse and human JAK2V617F mutated cell lines and primary hematopoietic progenitors from MPN patients were challenged with an allosteric (RAD001 and an ATP-competitive (PP242 mTOR inhibitor and two JAK2 inhibitors (AZD1480 and ruxolitinib. mTOR inhibitors effectively reduced proliferation and colony formation of cell lines through a slowed cell division mediated by changes in cell cycle transition to the S-phase. mTOR inhibitors also impaired the proliferation and prevented colony formation from MPN hematopoietic progenitors at doses significantly lower than healthy controls. JAK2 inhibitors produced similar antiproliferative effects in MPN cell lines and primary cells but were more potent inducers of apoptosis, as also supported by differential effects on cyclinD1, PIM1 and BcLxL expression levels. Co-treatment of mTOR inhibitor with JAK2 inhibitor resulted in synergistic activity against the proliferation of JAK2V617F mutated cell lines and significantly reduced erythropoietin-independent colony growth in patients with

  12. High-throughput screening to identify inhibitors of lysine demethylases.

    Science.gov (United States)

    Gale, Molly; Yan, Qin

    2015-01-01

    Lysine demethylases (KDMs) are epigenetic regulators whose dysfunction is implicated in the pathology of many human diseases including various types of cancer, inflammation and X-linked intellectual disability. Particular demethylases have been identified as promising therapeutic targets, and tremendous efforts are being devoted toward developing suitable small-molecule inhibitors for clinical and research use. Several High-throughput screening strategies have been developed to screen for small-molecule inhibitors of KDMs, each with advantages and disadvantages in terms of time, cost, effort, reliability and sensitivity. In this Special Report, we review and evaluate the High-throughput screening methods utilized for discovery of novel small-molecule KDM inhibitors.

  13. The 'retro-design' concept for novel kinase inhibitors.

    Science.gov (United States)

    Müller, Gerhard; Sennhenn, Peter C; Woodcock, Timothy; Neumann, Lars

    2010-07-01

    Protein kinases are among the most attractive therapeutic targets for a broad range of diseases. This feature review highlights and classifies the main design principles employed to generate active and selective kinase inhibitors. In particular, emphasis is focused on a fragment-based lead-generation approach, which constitutes a novel design method for developing type II kinase inhibitors with distinct binding kinetic attributes. This 'retro-design' strategy relies on a customized fragment library, and contrasts the traditional approach used in the design of type II inhibitors.

  14. Acalabrutinib (ACP-196: a selective second-generation BTK inhibitor

    Directory of Open Access Journals (Sweden)

    Jingjing Wu

    2016-03-01

    Full Text Available Abstract More and more targeted agents become available for B cell malignancies with increasing precision and potency. The first-in-class Bruton’s tyrosine kinase (BTK inhibitor, ibrutinib, has been in clinical use for the treatment of chronic lymphocytic leukemia, mantle cell lymphoma, and Waldenstrom’s macroglobulinemia. More selective BTK inhibitors (ACP-196, ONO/GS-4059, BGB-3111, CC-292 are being explored. Acalabrutinib (ACP-196 is a novel irreversible second-generation BTK inhibitor that was shown to be more potent and selective than ibrutinib. This review summarized the preclinical research and clinical data of acalabrutinib.

  15. Structure based design of 11β-HSD1 inhibitors.

    Science.gov (United States)

    Singh, Suresh; Tice, Colin

    2010-11-01

    Controlling elevated tissue-specific levels of cortisol may provide a novel therapeutic approach for treating metabolic syndrome. This concept has spurred large scale medicinal chemistry efforts in the pharmaceutical industry for the design of 11β-HSD1 inhibitors. High resolution X-ray crystal structures of inhibitors in complex with the enzyme have facilitated the structure-based design of diverse classes of molecules. A summary of binding modes, trends in structure-activity relationships, and the pharmacodynamic data of inhibitors from each class is presented.

  16. HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitors

    DEFF Research Database (Denmark)

    Vanangamudi, Murugesan; Poongavanam, Vasanthanathan; Namasivayam, Vigneshwaran

    2017-01-01

    BACKGROUND: Design of inhibitors for HIV-1 reverse transcriptase inhibition (HIV-1 RT) is one of the successful chemotherapies for the treatment of HIV infection. Among the inhibitors available for HIV-1 RT, non-nucleoside reverse transcriptase inhibitors (NNRTIs) have shown to be very promising......: The conformation dependent-alignment based (CoMFA and CoMSIA) methods have been proven very successful ligand based strategy in the drug design. Here, CoMFA and CoMSIA studies reported for structurally distinct NNRTIs including thiazolobenzimidazole, dipyridodiazepinone, 1,1,3-trioxo [1,2,4]-thiadiazine...

  17. HIV protease drug resistance and its impact on inhibitor design.

    Science.gov (United States)

    Ala, P J; Rodgers, J D; Chang, C H

    1999-07-01

    The primary cause of resistance to the currently available HIV protease inhibitors is the accumulation of multiple mutations in the viral protease. So far more than 20 substitutions have been observed in the active site, dimer interface, surface loops and flaps of the homodimer. While many mutations reduce the protease's affinity for inhibitors, others appear to enhance its catalytic efficiency. This high degree of genetic flexibility has made the protease an elusive drug target. The design of the next generation of HIV protease inhibitors will be discussed in light of the current structural information.

  18. Bicyclic peptide inhibitor of urokinase-type plasminogen activator

    DEFF Research Database (Denmark)

    Roodbeen, Renée; Jensen, Berit Paaske; Jiang, Longguang

    2013-01-01

    The development of protease inhibitors for pharmacological intervention has taken a new turn with the use of peptide-based inhibitors. Here, we report the rational design of bicyclic peptide inhibitors of the serine protease urokinase-type plasminogen activator (uPA), based on the established...... investigated the solution structures of the bicyclic peptide by NMR spectroscopy to map possible conformations. An X-ray structure of the bicyclic-peptide-uPA complex confirmed an interaction similar to that for the previous upain-1/upain-2-uPA complexes. These physical studies of the peptide...

  19. Pseudomonas aeruginosa toxin ExoU induces a PAF-dependent impairment of alveolar fibrin turnover secondary to enhanced activation of coagulation and increased expression of plasminogen activator inhibitor-1 in the course of mice pneumosepsis

    Directory of Open Access Journals (Sweden)

    Suassuna José HR

    2011-08-01

    Full Text Available Abstract Background ExoU, a Pseudomonas aeruginosa cytotoxin with phospholipase A2 activity, was shown to induce vascular hyperpermeability and thrombus formation in a murine model of pneumosepsis. In this study, we investigated the toxin ability to induce alterations in pulmonary fibrinolysis and the contribution of the platelet activating factor (PAF in the ExoU-induced overexpression of plasminogen activator inhibitor-1 (PAI-1. Methods Mice were intratracheally instilled with the ExoU producing PA103 P. aeruginosa or its mutant with deletion of the exoU gene. After 24 h, animal bronchoalveolar lavage fluids (BALF were analyzed and lung sections were submitted to fibrin and PAI-1 immunohistochemical localization. Supernatants from A549 airway epithelial cells and THP-1 macrophage cultures infected with both bacterial strains were also analyzed at 24 h post-infection. Results In PA103-infected mice, but not in control animals or in mice infected with the bacterial mutant, extensive fibrin deposition was detected in lung parenchyma and microvasculature whereas mice BALF exhibited elevated tissue factor-dependent procoagulant activity and PAI-1 concentration. ExoU-triggered PAI-1 overexpression was confirmed by immunohistochemistry. In in vitro assays, PA103-infected A549 cells exhibited overexpression of PAI-1 mRNA. Increased concentration of PAI-1 protein was detected in both A549 and THP-1 culture supernatants. Mice treatment with a PAF antagonist prior to PA103 infection reduced significantly PAI-1 concentrations in mice BALF. Similarly, A549 cell treatment with an antibody against PAF receptor significantly reduced PAI-1 mRNA expression and PAI-1 concentrations in cell supernatants, respectively. Conclusion ExoU was shown to induce disturbed fibrin turnover, secondary to enhanced procoagulant and antifibrinolytic activity during P. aeruginosa pneumosepsis, by a PAF-dependent mechanism. Besides its possible pathophysiological relevance, in

  20. Oral direct thrombin inhibitors or oral factor Xa inhibitors for the treatment of deep vein thrombosis.

    Science.gov (United States)

    Robertson, Lindsay; Kesteven, Patrick; McCaslin, James E

    2015-06-30

    Deep vein thrombosis (DVT) is a condition in which a clot forms in the deep veins, most commonly of the leg. It occurs in approximately 1 in 1,000 people. If left untreated, the clot can travel up to the lungs and cause a potentially life-threatening pulmonary embolism (PE). Previously, a DVT was treated with the anticoagulants heparin and vitamin K antagonists. However, two forms of novel oral anticoagulants (NOACs) have been developed: oral direct thrombin inhibitors (DTI) and oral factor Xa inhibitors. The new drugs have characteristics that may be favourable over conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or re-dosing and few known drug interactions. To date, no Cochrane review has measured the effectiveness and safety of these drugs in the treatment of DVT. To assess the effectiveness of oral DTIs and oral factor Xa inhibitors for the treatment of DVT. The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched January 2015) and the Cochrane Register of Studies (last searched January 2015). We searched clinical trials databases for details of ongoing or unpublished studies and the reference lists of relevant articles retrieved by electronic searches for additional citations. We included randomised controlled trials in which people with a DVT confirmed by standard imaging techniques, were allocated to receive an oral DTI or an oral factor Xa inhibitor for the treatment of DVT. Two review authors (LR, JM) independently extracted the data and assessed the risk of bias in the trials. Any disagreements were resolved by discussion with the third review author (PK). We performed meta-analyses when we considered heterogeneity low. The two primary outcomes were recurrent VTE and PE. Other outcomes included all-cause mortality and major bleeding. We calculated all outcomes using an odds ratio (OR) with a 95% confidence interval (CI). We included

  1. Novel orally bioavailable EZH1/2 dual inhibitors with greater antitumor efficacy than an EZH2 selective inhibitor.

    Science.gov (United States)

    Honma, Daisuke; Kanno, Osamu; Watanabe, Jun; Kinoshita, Junzo; Hirasawa, Makoto; Nosaka, Emi; Shiroishi, Machiko; Takizawa, Takeshi; Yasumatsu, Isao; Horiuchi, Takao; Nakao, Akira; Suzuki, Keisuke; Yamasaki, Tomonori; Nakajima, Katsuyoshi; Hayakawa, Miho; Yamazaki, Takanori; Yadav, Ajay Singh; Adachi, Nobuaki

    2017-10-01

    Polycomb repressive complex 2 (PRC2) methylates histone H3 lysine 27 and represses gene expression to regulate cell proliferation and differentiation. Enhancer of zeste homolog 2 (EZH2) or its close homolog EZH1 functions as a catalytic subunit of PRC2, so there are two PRC2 complexes containing either EZH2 or EZH1. Tumorigenic functions of EZH2 and its synthetic lethality with some subunits of SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complexes have been observed. However, little is known about the function of EZH1 in tumorigenesis. Herein, we developed novel, orally bioavailable EZH1/2 dual inhibitors that strongly and selectively inhibited methyltransferase activity of both EZH2 and EZH1. EZH1/2 dual inhibitors suppressed trimethylation of histone H3 lysine 27 in cells more than EZH2 selective inhibitors. They also showed greater antitumor efficacy than EZH2 selective inhibitor in vitro and in vivo against diffuse large B-cell lymphoma cells harboring gain-of-function mutation in EZH2. A hematological cancer panel assay indicated that EZH1/2 dual inhibitor has efficacy against some lymphomas, multiple myeloma, and leukemia with fusion genes such as MLL-AF9, MLL-AF4, and AML1-ETO. A solid cancer panel assay demonstrated that some cancer cell lines are sensitive to EZH1/2 dual inhibitor in vitro and in vivo. No clear correlation was detected between sensitivity to EZH1/2 dual inhibitor and SWI/SNF mutations, with a few exceptions. Severe toxicity was not seen in rats treated with EZH1/2 dual inhibitor for 14 days at drug levels higher than those used in the antitumor study. Our results indicate the possibility of EZH1/2 dual inhibitors for clinical applications. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  2. Prodrugs of herpes simplex thymidine kinase inhibitors.

    Science.gov (United States)

    Yanachkova, Milka; Xu, Wei-Chu; Dvoskin, Sofya; Dix, Edward J; Yanachkov, Ivan B; Focher, Federico; Savi, Lida; Sanchez, M Dulfary; Foster, Timothy P; Wright, George E

    2015-04-01

    Because guanine-based herpes simplex virus thymidine kinase inhibitors are not orally available, we synthesized various 6-deoxy prodrugs of these compounds and evaluated them with regard to solubility in water, oral bioavailability, and efficacy to prevent herpes simplex virus-1 reactivation from latency in a mouse model. Organic synthesis was used to prepare compounds, High Performance Liquid Chromatography (HPLC) to analyze hydrolytic conversion, Mass Spectrometry (MS) to measure oral bioavailability, and mouse latent infection and induced reactivation to evaluate the efficacy of a specific prodrug. Aqueous solubilities of prodrugs were improved, oxidation of prodrugs by animal cytosols occurred in vitro, and oral absorption of the optimal prodrug sacrovir™ (6-deoxy-mCF3PG) in the presence of the aqueous adjuvant Soluplus® and conversion to active compound N(2)-[3-(trifluoromethyl)pheny])guanine (mCF3PG) were accomplished in mice. Treatment of herpes simplex virus-1 latent mice with sacrovir™ in 1% Soluplus in drinking water significantly suppressed herpes simplex virus-1 reactivation and viral genomic replication. Ad libitum oral delivery of sacrovir™ was effective in suppressing herpes simplex virus-1 reactivation in ocularly infected latent mice as measured by the numbers of mice shedding infectious virus at the ocular surface, numbers of trigeminal ganglia positive for infectious virus, number of corneas that had detectable infectious virus, and herpes simplex virus-1 genome copy numbers in trigeminal ganglia following reactivation. These results demonstrate the statistically significant effect of the prodrug on suppressing herpes simplex virus-1 reactivation in vivo. © The Author(s) 2015.

  3. WNK1 is an unexpected autophagy inhibitor

    Science.gov (United States)

    Gallolu Kankanamalage, Sachith; Lee, A-Young; Wichaidit, Chonlarat; Lorente-Rodriguez, Andres; Shah, Akansha M.; Stippec, Steve; Whitehurst, Angelique W.; Cobb, Melanie H.

    2017-01-01

    ABSTRACT Autophagy is a cellular degradation pathway that is essential to maintain cellular physiology, and deregulation of autophagy leads to multiple diseases in humans. In a recent study, we discovered that the protein kinase WNK1 (WNK lysine deficient protein kinase 1) is an inhibitor of autophagy. The loss of WNK1 increases both basal and starvation-induced autophagy. In addition, the depletion of WNK1 increases the activation of the class III phosphatidylinositol 3-kinase (PtdIns3K) complex, which is required to induce autophagy. Moreover, the loss of WNK1 increases the expression of ULK1 (unc-51 like kinase 1), which is upstream of the PtdIns3K complex. It also increases the pro-autophagic phosphorylation of ULK1 at Ser555 and the activation of AMPK (AMP-activated protein kinase), which is responsible for that phosphorylation. The inhibition of AMPK by compound C decreases the magnitude of autophagy induction following WNK1 loss; however, it does not prevent autophagy induction. We found that the UVRAG (UV radiation resistance associated gene), which is a component of the PtdIns3K, binds to the N-terminal region of WNK1. Moreover, WNK1 partially colocalizes with UVRAG and this colocalization decreases when autophagy is stimulated in cells. The loss of WNK1 also alters the cellular distribution of UVRAG. The depletion of the downstream target of WNK1, OXSR1/OSR1 (oxidative-stress responsive 1) has no effect on autophagy, whereas the depletion of its relative STK39/SPAK (serine/threonine kinase 39) induces autophagy under nutrient-rich and starved conditions. PMID:28282258

  4. Inhibitor development after liver transplantation in congenital factor VII deficiency.

    Science.gov (United States)

    See, W-S Q; Chang, K-O; Cheuk, D K-L; Leung, Y-Y R; Chan, G C-F; Chan, S-C; Ha, S-Y

    2016-09-01

    Congenital factor VII (FVII) deficiency is the commonest type of the rare bleeding disorders. Very few cases of congenital FVII deficiency developed inhibitor and liver transplant is considered as definitive treatment. In the literature, twelve patients with congenital FVII deficiency developed inhibitors. Two had spontaneous resolution of inhibitors and one did not respond to high dose recombinant factor VIIa (rFVIIa) and died. Regarding liver transplant in congenital FVII patients, seven patients underwent liver transplant with good prognosis. We report a 5-year-old girl with confirmed severe congenital FVII deficiency since neonatal period. She suffered from recurrent intracranial bleeding despite rFVIIa replacement. After auxiliary liver transplant at the age of 4, she continued to show persistent deranged clotting profile and was found to have inhibitor towards FVII. Interestingly, she was still responsive to rFVIIa replacement. © 2016 John Wiley & Sons Ltd.

  5. Effect of histone deacetylase inhibitor, trichostatin A, on cartilage ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research June 2017; 16 (6): 1253-1257 ... Conclusion: Treatment with trichostatin A, an HDAC inhibitor, enhances cartilage regeneration in rabbit ..... deacetylase activity in rheumatoid arthritis and asthma.

  6. Acquired high titre factor VIII inhibitor with underlying polyarteritis nodosa.

    Science.gov (United States)

    Snowden, J A; Hutchings, M; Spearing, R; Patton, W N

    1997-05-01

    We here present the case of a 70-year-old woman referred to our unit for investigation of bleeding. Investigations confirmed a high titre acquired Factor VIII inhibitor. In association there was relapse of systemic illness associated with anti-neutrophil cytoplasmic antibodies (atypical pattern) for which she had been treated five years previously. Immunosuppression was attempted, but it failed to have an impact both on the inhibitor titre and on the underlying disorder. The patient died from multi-organ failure and massive chest hemorrhage. Post-mortem showed necrotizing vasculitis of medium sized vessels at several sites, including the kidney, consistent with a diagnosis of polyarteritis nodosa. Although it is well recognised that Factor VIII inhibitors are found in conjunction with autoimmune disorders, this case is significant in that it is the first associated with histologically proven polyarteritis nodosa type vasculitis. The case illustrates the difficulties in the investigation and management of patients with acquired high titre Factor VIII inhibitors.

  7. Are SGLT2 inhibitors reasonable antihypertensive drugs and renoprotective?

    Science.gov (United States)

    Lovshin, J A; Gilbert, R E

    2015-06-01

    By eliminating glucose in the urine, the sodium-glucose-linked cotransporter-2 (SGLT2) inhibitors act as osmotic diuretics to lower blood pressure in addition to reducing plasma glucose and assisting with weight loss. While not approved as antihypertensive agents, the ability of this new class of antihyperglycemic agents to lower blood pressure is not insubstantial, and while not used primarily for this indication, they may assist diabetic individuals in attaining currently recommended blood pressure targets. In addition to lowering systemic pressure, preclinical and exploratory human studies suggest that SGLT2 inhibitors may also lower intraglomerular pressure, potentially reducing the rate of GFR decline in patients with diabetic nephropathy. However, given the lack of clinically meaningful endpoint data, the use of SGLT2 inhibitors, primarily, as either antihypertensive or renoprotective agents would, at present, be premature. Fortunately, further insight will be garnered from large, randomized controlled trials that will assess the effects of various SGLT2 inhibitors on cardiovascular and renal outcomes.

  8. Identification of catechols as histone-lysine demethylase inhibitors

    DEFF Research Database (Denmark)

    Nielsen, Anders L; Kristensen, Line H; Stephansen, Karen B

    2012-01-01

    Identification of inhibitors of histone-lysine demethylase (HDM) enzymes is important because of their involvement in the development of cancer. An ELISA-based assay was developed for identification of inhibitors of the HDM KDM4C in a natural products library. Based on one of the hits with affinity...... in the low µM range (1, a catechol), a subset of structurally related compounds was selected and tested against a panel of HDMs. In this subset, two inhibitors (2 and 10) had comparable affinities towards KDM4C and KDM6A but no effect on PHF8. One inhibitor restored H3K9me3 levels in KDM4C transfected U2-OS...

  9. Effects of protease inhibitors on radiation transformation in vitro

    International Nuclear Information System (INIS)

    Kennedy, A.R.; Little, J.B.

    1981-01-01

    We have investigated the effects of three protease inhibitors, antipain, leupeptin, and soybean trypsin inhibitor, on the induction of oncogenic transformation in mouse C3H10T 1/2 cells by X-rays. The patterns of inhibition by the three protease inhibitors were different. Antipain was the most effective, having the ability to suppress completely radiation transformation as well as radiation transformation enhanced by the phorbol ester promoting agent 12-O-tetradecanoylphorbol-13-acetate. The fact that antipain could suppress transformation when present for only 1 day following irradiation suggests that an effect on a DNA repair process might be important in its action. Leupeptin was less effective than antipain in its inhibition of radiation transformation. Soybean trypsin inhibitor suppressed only the promotional effects of 12-O-tetradecanoylphorbol-13-acetate on transformation. Our results suggest that there may be more than one protease involved in carcinogenesis

  10. Fermentable sugars and microbial inhibitors formation from two ...

    African Journals Online (AJOL)

    ... under low severity factor and its enzymatic degradability was investigated in this ... The highest glucan conversion and recovery at the optimum conditions were ... reduce microbial inhibitors formation and excessive biomass processing cost.

  11. ETORICOXIB IS A NEW SELECTIVE CYCLOOXYGENASE-2 INHIBITOR

    Directory of Open Access Journals (Sweden)

    A E Karateev

    2009-01-01

    Full Text Available The paper provides the clinical characteristics of etoricoxib (Arcoxia, a new selective cyclooxygenase-2 inhibitor having unique properties, which permits it to be distinguished among other nonsteroidal anti-inflammatory agents.

  12. ETORICOXIB IS A NEW SELECTIVE CYCLOOXYGENASE-2 INHIBITOR

    Directory of Open Access Journals (Sweden)

    A E Karateev

    2009-06-01

    Full Text Available The paper provides the clinical characteristics of etoricoxib (Arcoxia, a new selective cyclooxygenase-2 inhibitor having unique properties, which permits it to be distinguished among other nonsteroidal anti-inflammatory agents.

  13. SAH derived potent and selective EZH2 inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Pei-Pei; Huang, Buwen; Zehnder, Luke; Tatlock, John; Bingham, Patrick; Krivacic, Cody; Gajiwala, Ketan; Diehl, Wade; Yu, Xiu; Maegley, Karen A.

    2015-04-01

    A series of novel enhancer of zeste homolog 2 (EZH2) inhibitors was designed based on the chemical structure of the histone methyltransferase (HMT) inhibitor SAH (S-adenosyl-l-homocysteine). These nucleoside-based EZH2 inhibitors blocked the methylation of nucleosomes at H3K27 in biochemical assays employing both WT PRC2 complex as well as a Y641N mutant PRC2 complex. The most potent compound, 27, displayed IC50’s against both complexes of 270 nM and 70 nM, respectively. To our knowledge, compound 27 is the most potent SAH-derived inhibitor of the EZH2 PRC2 complex yet identified. This compound also displayed improved potency, lipophilic efficiency (LipE), and selectivity profile against other lysine methyltransferases compared with SAH.

  14. Aromatase inhibitor (anastrozole) affects growth of endometrioma cells in culture.

    Science.gov (United States)

    Badawy, Shawky Z A; Brown, Shereene; Kaufman, Lydia; Wojtowycz, Martha A

    2015-05-01

    To study the effects of aromatase inhibitor (anastrozole) on the growth and estradiol secretion of endometrioma cells in culture. Endometrioma cells are grown in vitro until maximum growth before used in this study. This was done in the research laboratory for tissue culture, in an academic hospital. Testosterone at a concentration of 10 μg/mL was added as a substrate for the intracellular aromatase. In addition, aromatase inhibitor was added at a concentration of 200 and 300 μg/mL. The effect on cell growth and estradiol secretion is evaluated using Student's t-test. The use of testosterone increased estradiol secretion by endometrioma cells in culture. The use of aromatase inhibitor significantly inhibited the growth of endometrioma cells, and estradiol secretion. Aromatase inhibitor (anastrozole) may be an effective treatment for endometriosis due to inhibition of cellular aromatase. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Effectiveness of Phosphodiesterase-5 Inhibitor Therapy for Portopulmonary Hypertension

    Directory of Open Access Journals (Sweden)

    Jolene H Fisher

    2015-01-01

    Full Text Available BACKGROUND: Portopulmonary hypertension is associated with significant morbidity and mortality. Phosphodiesterase-5 inhibitor therapy is efficacious in other causes of WHO group I pulmonary arterial hypertension.

  16. PLANTS AS A SOURCE OF GREEN CORROSION INHIBITORS ...

    African Journals Online (AJOL)

    Mgina

    Acacia senegal) exhibit good inhibition characteristics to corrosion on mild steel under fresh water medium and the ... as corrosion inhibitors for metals in various corrosive media ..... alloy corrosion in chloride solution", J. Appl. Electrochem.

  17. The binding mechanism of a peptidic cyclic serine protease inhibitor

    DEFF Research Database (Denmark)

    Jiang, Longguang; Svane, Anna Sigrid P.; Sørensen, Hans Peter

    2011-01-01

    Serine proteases are classical objects for studies of catalytic and inhibitory mechanisms as well as interesting as therapeutic targets. Since small-molecule serine protease inhibitors generally suffer from specificity problems, peptidic inhibitors, isolated from phage-displayed peptide libraries......, have attracted considerable attention. Here, we have investigated the mechanism of binding of peptidic inhibitors to serine protease targets. Our model is upain-1 (CSWRGLENHRMC), a disulfide-bond-constrained competitive inhibitor of human urokinase-type plasminogen activator with a noncanonical...... inhibitory mechanism and an unusually high specificity. Using a number of modified variants of upain-1, we characterised the upain-1-urokinase-type plasminogen activator complex using X-ray crystal structure analysis, determined a model of the peptide in solution by NMR spectroscopy, and analysed binding...

  18. Rapid synthesis of triazine inhibitors of inosine monophosphate dehydrogenase.

    Science.gov (United States)

    Pitts, William J; Guo, Junqing; Dhar, T G Murali; Shen, Zhongqi; Gu, Henry H; Watterson, Scott H; Bednarz, Mark S; Chen, Bang Chi; Barrish, Joel C; Bassolino, Donna; Cheney, Daniel; Fleener, Catherine A; Rouleau, Katherine A; Hollenbaugh, Diane L; Iwanowicz, Edwin J

    2002-08-19

    A series of novel triazine-based small molecule inhibitors (IV) of inosine monophosphate dehydrogenase was prepared. The synthesis and the structure-activity relationships (SAR) derived from in vitro studies are described.

  19. Novel amide-based inhibitors of inosine 5'-monophosphate dehydrogenase.

    Science.gov (United States)

    Watterson, Scott H; Liu, Chunjian; Dhar, T G Murali; Gu, Henry H; Pitts, William J; Barrish, Joel C; Fleener, Catherine A; Rouleau, Katherine; Sherbina, N Z; Hollenbaugh, Diane L; Iwanowicz, Edwin J

    2002-10-21

    A series of novel amide-based small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH) was explored. The synthesis and the structure-activity relationships (SARs) derived from in vitro studies are described.

  20. Novel Combinatorial Chemistry-Derived Inhibitors of Oncogenic Phosphatases

    National Research Council Canada - National Science Library

    Lazo, John

    1999-01-01

    Our overall goal of this US Army Breast Cancer Grant entitled "Novel Combinatorial Chemistry-Derived Inhibitors of Oncogenic Phosphatases" is to identity and develop novel therapeutic agents for human breast cancer...

  1. Proteasome inhibitor carfilzomib interacts synergistically with histone deacetylase inhibitor vorinostat in Jurkat T-leukemia cells.

    Science.gov (United States)

    Gao, Minjie; Gao, Lu; Tao, Yi; Hou, Jun; Yang, Guang; Wu, Xiaosong; Xu, Hongwei; Tompkins, Van S; Han, Ying; Wu, Huiqun; Zhan, Fenghuang; Shi, Jumei

    2014-06-01

    In the present study, we investigated the interactions between proteasome inhibitor carfilzomib (CFZ) and histone deacetylase inhibitor vorinostat in Jurkat T-leukemia cells. Coexposure of cells to minimally lethal concentrations of CFZ with very low concentration of vorinostat resulted in synergistic antiproliferative effects and enhanced apoptosis in Jurkat T-leukemia cells, accompanied with the sharply increased reactive oxygen species (ROS), the striking decrease in the mitochondrial membrane potential (MMP), the increased release of cytochrome c, the enhanced activation of caspase-9 and -3, and the cleavage of PARP. The combined treatment of Jurkat cells pre-treated with ROS scavengers N-acetylcysteine (NAC) significantly blocked the loss of mitochondrial membrane potential, suggesting that ROS generation was a former event of the loss of mitochondrial membrane potential. Furthermore, NAC also resulted in a marked reduction in apoptotic cells, indicating a critical role for increased ROS generation by combined treatment. In addition, combined treatment arrested the cell cycle in G2-M phase. These results imply that CFZ interacted synergistically with vorinostat in Jurkat T-leukemia cells, which raised the possibility that the combination of carfilzomib with vorinostat may represent a novel strategy in treating T-cell Leukemia. © The Author 2014. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

  2. Fluoxetine Is a Potent Inhibitor of Coxsackievirus Replication

    OpenAIRE

    Zuo, Jun; Quinn, Kevin K.; Kye, Steve; Cooper, Paige; Damoiseaux, Robert; Krogstad, Paul

    2012-01-01

    No antiviral drugs currently exist for the treatment of enterovirus infections, which are often severe and potentially life threatening. Molecular screening of small molecule libraries identified fluoxetine, a selective serotonin reuptake inhibitor, as a potent inhibitor of coxsackievirus replication. Fluoxetine did not interfere with either viral entry or translation of the viral genome. Instead, fluoxetine and its metabolite norfluoxetine markedly reduced the synthesis of viral RNA and prot...

  3. Enhancing Immune Checkpoint Inhibitor Therapy in Kidney Cancer

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-15-1-0141 TITLE: Enhancing Immune Checkpoint Inhibitor therapy in Kidney Cancer PRINCIPAL INVESTIGATOR: Hans-Joerg Hammers...SUBTITLE Enhancing Immune Checkpoint Inhibitor therapy in Kidney Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH- 15-1-0141 5c. PROGRAM ELEMENT NUMBER...immune checkpoint inhibition in kidney cancer . The work is designed to test different strategies to induce or enhance the abscopal in a kidney cancer

  4. Carprofen analogues as sirtuin inhibitors: enzyme and cellular studies.

    Science.gov (United States)

    Mellini, Paolo; Carafa, Vincenzo; Di Rienzo, Barbara; Rotili, Dante; De Vita, Daniela; Cirilli, Roberto; Gallinella, Bruno; Provvisiero, Donatella Paola; Di Maro, Salvatore; Novellino, Ettore; Altucci, Lucia; Mai, Antonello

    2012-11-01

    The best of both: SIRT1/2 inhibitors were developed by combining chemical features of selisistat (SIRT1-selective inhibitor; blue) and carprofen (anti-inflammatory drug; red). The most potent compound (shown) increased acetyl-p53 and acetyl-α-tubulin levels, and induced slight apoptosis at 50 μM in U937 cells, differently from selisistat and carprofen. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Small Molecule Inhibitors That Selectively Block Dengue Virus Methyltransferase*

    OpenAIRE

    Lim, Siew Pheng; Sonntag, Louis Sebastian; Noble, Christian; Nilar, Shahul H.; Ng, Ru Hui; Zou, Gang; Monaghan, Paul; Chung, Ka Yan; Dong, Hongping; Liu, Boping; Bodenreider, Christophe; Lee, Gladys; Ding, Mei; Chan, Wai Ling; Wang, Gang

    2010-01-01

    Crystal structure analysis of Flavivirus methyltransferases uncovered a flavivirus-conserved cavity located next to the binding site for its cofactor, S-adenosyl-methionine (SAM). Chemical derivatization of S-adenosyl-homocysteine (SAH), the product inhibitor of the methylation reaction, with substituents that extend into the identified cavity, generated inhibitors that showed improved and selective activity against dengue virus methyltransferase (MTase), but not related human enzymes. Crysta...

  6. Non-genetic risk factors in haemophilia A inhibitor management

    DEFF Research Database (Denmark)

    Löfgren, Karin Maria; Søndergaard, H.; Skov, Søren

    2016-01-01

    In haemophilia A (HA) management, antidrug antibodies, or inhibitors, are a serious complication that renders factor VIII (FVIII) replacement therapy ineffective, increases morbidity and reduces quality of life for affected patients. Inhibitor development aetiology is multifactorial and covers both...... stressed, injured or dying cells can activate an immune reaction, without the involvement of foreign antigens. Bleeds, trauma, surgery or concomitant infection could be events initiating danger signalling in HA patients, resulting in an immune reaction towards administered FVIII that otherwise would pass...

  7. Histone deacetylase inhibitors for the treatment of cancer stem cells

    Czech Academy of Sciences Publication Activity Database

    Dvořáková, Marcela; Vaněk, Tomáš

    2016-01-01

    Roč. 7, č. 12 (2016), s. 2217-2231 ISSN 2040-2503 R&D Projects: GA MŠk LD14128 Institutional support: RVO:61389030 Keywords : acute myeloid-leukemia * epithelial-mesenchymal transition * acute myelogenous leukemia * tumor-initiating cells * human aml cells * breast-cancer * hdac inhibitors * sirtuin inhibitors * colorectal-cancer * anticancer agents Subject RIV: CC - Organic Chemistry Impact factor: 2.608, year: 2016

  8. [Insect cholinesterases and irreversible inhibitors. Statistical treatment of the data].

    Science.gov (United States)

    Moralev, S N

    2010-01-01

    The data on sensitivity of cholinesterases (ChE) of different insects to reversible inhibitors, as well as the data on physico-chemical parameters of amino acids constituting their active centers, were treated by factor analysis and juxtaposed. It is shown that both these characteristics are related to taxonomical belonging of insects. It is revealed the "material substrate" of the factors determining inhibitor action specificity, which are specific sites in ChE active center.

  9. Structure of a Kunitz-type potato cathepsin D inhibitor

    Czech Academy of Sciences Publication Activity Database

    Guo, J.; Erskine, P. T.; Coker, A. R.; Wood, S. P.; Cooper, J. B.; Mareš, Michael; Baudyš, Miroslav

    2015-01-01

    Roč. 192, č. 3 (2015), s. 554-560 ISSN 1047-8477 R&D Projects: GA ČR GA15-18929S; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : potato cathepsin D inhibitor * Kunitz-type protease inhibitor * protein X-ray structure * reactive-site loop * docking Subject RIV: CE - Biochemistry Impact factor: 2.570, year: 2015

  10. On the use of triazines as inhibitors of steel corrosion

    International Nuclear Information System (INIS)

    Sizaya, O.I.; Andrushko, A.P.

    2004-01-01

    A possibility of using substandard pesticides as a raw materials for synthesis of a set of triazines and also using them as a inhibitors of acidic corrosion of steel 20, as well as additions to epoxy powder coatings is considered. It is shown that triazines studied are inhibitors of acidic corrosion of steel 20. 2,4-di(ethylamino)-6-phenylhydrazono-1,3,5-triazine (In 4) has a maximum inhibiting effect among the studied compounds [ru

  11. New synthetic thrombin inhibitors: molecular design and experimental verification.

    Directory of Open Access Journals (Sweden)

    Elena I Sinauridze

    Full Text Available BACKGROUND: The development of new anticoagulants is an important goal for the improvement of thromboses treatments. OBJECTIVES: The design, synthesis and experimental testing of new safe and effective small molecule direct thrombin inhibitors for intravenous administration. METHODS: Computer-aided molecular design of new thrombin inhibitors was performed using our original docking program SOL, which is based on the genetic algorithm of global energy minimization in the framework of a Merck Molecular Force Field. This program takes into account the effects of solvent. The designed molecules with the best scoring functions (calculated binding energies were synthesized and their thrombin inhibitory activity evaluated experimentally in vitro using a chromogenic substrate in a buffer system and using a thrombin generation test in isolated plasma and in vivo using the newly developed model of hemodilution-induced hypercoagulation in rats. The acute toxicities of the most promising new thrombin inhibitors were evaluated in mice, and their stabilities in aqueous solutions were measured. RESULTS: New compounds that are both effective direct thrombin inhibitors (the best K(I was 1111.1 mg/kg. A plasma-substituting solution supplemented with one of the new inhibitors prevented hypercoagulation in the rat model of hemodilution-induced hypercoagulation. Activities of the best new inhibitors in physiological saline (1 µM solutions were stable after sterilization by autoclaving, and the inhibitors remained stable at long-term storage over more than 1.5 years at room temperature and at 4°C. CONCLUSIONS: The high efficacy, stability and low acute toxicity reveal that the inhibitors that were developed may be promising for potential medical applications.

  12. Kinase inhibitors: a new class of antirheumatic drugs

    Directory of Open Access Journals (Sweden)

    Kyttaris VC

    2012-09-01

    Full Text Available Vasileios C KyttarisDivision of Rheumatology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USAAbstract: The outlook for patients with rheumatoid arthritis has improved significantly over the last three decades with the use of disease-modifying antirheumatic drugs. However, despite the use of methotrexate, cytokine inhibitors, and molecules targeting T and B cells, a percentage of patients do not respond or lose their response over time. The autoimmune process in rheumatoid arthritis depends on activation of immune cells, which utilize intracellular kinases to respond to external stimuli such as cytokines, immune complexes, and antigens. In the past decade, small molecules targeting several kinases, such as p38 MAPK, Syk, and JAK have been developed. Several p38 MAPK inhibitors proved ineffective in treating rheumatoid arthritis. The Syk inhibitor, fostamatinib, proved superior to placebo in Phase II trials and is currently under Phase III investigation. Tofacitinib, a JAK1/3 inhibitor, was shown to be efficacious in two Phase III trials, while VX-509, a JAK3 inhibitor, showed promising results in a Phase II trial. Fostamatinib and tofacitinib were associated with increased rates of infection, elevation of liver enzymes, and neutropenia. Moreover, fostamatinib caused elevations of blood pressure and diarrhea, while tofacitinib was associated with an increase in creatinine and elevation of lipid levels.Keywords: rheumatoid arthritis, kinase inhibitors, mitogen-activated phosphokinase p38, spleen tyrosine kinase, Janus kinases

  13. FAITH – Fast Assembly Inhibitor Test for HIV

    Energy Technology Data Exchange (ETDEWEB)

    Hadravová, Romana [Institute of Organic Chemistry and Biochemistry IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague (Czech Republic); Rumlová, Michaela, E-mail: michaela.rumlova@vscht.cz [Institute of Organic Chemistry and Biochemistry IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague (Czech Republic); Department of Biotechnology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague (Czech Republic); Ruml, Tomáš, E-mail: tomas.ruml@vscht.cz [Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 3, 166 28 Prague (Czech Republic)

    2015-12-15

    Due to the high number of drug-resistant HIV-1 mutants generated by highly active antiretroviral therapy (HAART), there is continuing demand for new types of inhibitors. Both the assembly of the Gag polyprotein into immature and mature HIV-1 particles are attractive candidates for the blocking of the retroviral life cycle. Currently, no therapeutically-used assembly inhibitor is available. One possible explanation is the lack of a reliable and simple assembly inhibitor screening method. To identify compounds potentially inhibiting the formation of both types of HIV-1 particles, we developed a new fluorescent high-throughput screening assay. This assay is based on the quantification of the assembly efficiency in vitro in a 96-well plate format. The key components of the assay are HIV-1 Gag-derived proteins and a dual-labelled oligonucleotide, which emits fluorescence only when the assembly of retroviral particles is inhibited. The method was validated using three (CAI, BM2, PF74) reported assembly inhibitors. - Highlights: • Allows screening of assembly inhibitors of both mature and immature HIV-1 particles. • Based on Gag-derived proteins with CA in mature or immature conformation. • Simple and sensitive method suitable for high-throughput screening of inhibitors. • Unlike in other HIV assembly methods, works under physiological conditions. • No washing steps are necessary.

  14. FAITH – Fast Assembly Inhibitor Test for HIV

    International Nuclear Information System (INIS)

    Hadravová, Romana; Rumlová, Michaela; Ruml, Tomáš

    2015-01-01

    Due to the high number of drug-resistant HIV-1 mutants generated by highly active antiretroviral therapy (HAART), there is continuing demand for new types of inhibitors. Both the assembly of the Gag polyprotein into immature and mature HIV-1 particles are attractive candidates for the blocking of the retroviral life cycle. Currently, no therapeutically-used assembly inhibitor is available. One possible explanation is the lack of a reliable and simple assembly inhibitor screening method. To identify compounds potentially inhibiting the formation of both types of HIV-1 particles, we developed a new fluorescent high-throughput screening assay. This assay is based on the quantification of the assembly efficiency in vitro in a 96-well plate format. The key components of the assay are HIV-1 Gag-derived proteins and a dual-labelled oligonucleotide, which emits fluorescence only when the assembly of retroviral particles is inhibited. The method was validated using three (CAI, BM2, PF74) reported assembly inhibitors. - Highlights: • Allows screening of assembly inhibitors of both mature and immature HIV-1 particles. • Based on Gag-derived proteins with CA in mature or immature conformation. • Simple and sensitive method suitable for high-throughput screening of inhibitors. • Unlike in other HIV assembly methods, works under physiological conditions. • No washing steps are necessary.

  15. Cardiovascular effects of sodium glucose cotransporter 2 inhibitors

    Directory of Open Access Journals (Sweden)

    Santos Cavaiola T

    2018-04-01

    Full Text Available Tricia Santos Cavaiola, Jeremy Pettus Division of Endocrinology and Metabolism, University of California San Diego, San Diego, CA, USA Abstract: As the first cardiovascular (CV outcome trial of a glucose-lowering agent to demonstrate a reduction in the risk of CV events in patients with type 2 diabetes mellitus (T2DM, the EMPAgliflozin Removal of Excess Glucose: Cardiovascular OUTCOME Event Trial in Type 2 Diabetes Mellitus Patients (EMPA-REG OUTCOME® trial, which investigated the sodium glucose cotransporter 2 (SGLT2 inhibitor empagliflozin, has generated great interest among health care professionals. CV outcomes data for another SGLT2 inhibitor, canagliflozin, have been published recently in the CANagliflozin CardioVascular Assessment Study (CANVAS Program, as have CV data from the retrospective real-world study Comparative Effectiveness of Cardiovascular Outcomes in New Users of Sodium-Glucose Cotransporter-2 Inhibitors (CVD-REAL, which compared SGLT2 inhibitors with other classes of glucose-lowering drugs. This review discusses the results of these three studies and, with a focus on EMPA-REG OUTCOME, examines the possible mechanisms by which SGLT2 inhibitors may reduce CV risk in patients with T2DM. Keywords: canagliflozin, cardiovascular outcomes, dapagliflozin, empagliflozin, mechanisms, sodium glucose cotransporter 2 inhibitors

  16. Synthesis and Application of Pyrrolidone-containing Shale Inhibitors

    Science.gov (United States)

    Liu, Yonggui; Hou, Jie; Zhang, Yang; Yan, Jing; Song, Tao; Xu, Yongjun

    2018-03-01

    New generation polyamine inhibitors are amino-terminated polyethers with excellent inhibiting capabilities; they play a key role in borehole stabilization and reservoir protection. However, polyamine inhibitors are limited by their poor thermal stability, which can be attributed to the presence of ether bonds in their molecular structures. We propose a three-step synthesis approach fora novel pyrrolidone-containing polyamine inhibitor (DYNP) by introducing N-vinyl-2-pyrrolidone (NVP) on divinyloxyethane. This polyamine inhibitor exhibits an optimized molecular structure and has enhanced heat resistance. Characterizations by infrared (IR) spectroscopy and evaluation tests demonstrate several advantages of DYNP inhibitors, including excellent inhibiting capability (superior to similar materials such as polyamines), improved heat resistance (reasonable stability at temperatures up to 240°C), and good compatibility with both fresh water and salt water drilling fluids. These can be attributed to the presence of considerable amounts of amino groups in the repeating unit of DYNP molecules. The DYNP inhibitor was applied in over 20 boreholes in tight oil blocks in Daqing Oilfield to relieve hydration of formations with high shale contents. For instance, drilling in the 2033.5m horizontal section of Dragon 2 borehole was smooth, with a borehole diameter expansion ratio below 10%.

  17. Inhibitor specificity of recombinant and endogenous caspase-9.

    Science.gov (United States)

    Ryan, Ciara A; Stennicke, Henning R; Nava, Victor E; Burch, Jennifer B; Hardwick, J Marie; Salvesen, Guy S

    2002-01-01

    Apoptosis triggered through the intrinsic pathway by radiation and anti-neoplastic drugs is initiated by the activation of caspase-9. To elucidate control mechanisms in this pathway we used a range of synthetic and natural reagents. The inhibitory potency of acetyl-Asp-Glu-Val-Asp-aldehyde ('Ac-DEVD-CHO'), benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone ('Z-VAD-FMK') and the endogenous caspase inhibitor X-chromosome-linked inhibitor of apoptosis protein ('XIAP') against recombinant caspase-9 were predictive of the efficacy of these compounds in a cell-free system. However, the viral proteins CrmA and p35, although potent inhibitors of recombinant caspase-9, had almost no ability to block caspase-9 in this system. These findings were also mirrored in cell expression studies. We hypothesize that the viral inhibitors CrmA and p35 are excluded from reacting productively with the natural form of active caspase-9 in vivo, making the potency of inhibitors highly context-dependent. This is supported by survival data from a mouse model of apoptosis driven by Sindbis virus expressing either p35 or a catalytic mutant of caspase-9. These results consolidate previous findings that CrmA is a potent inhibitor of caspase-9 in vitro, yet fails to block caspase-9-mediated cell death. PMID:12067274

  18. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    International Nuclear Information System (INIS)

    Nicolescu, Adrian C.; Holt, Andrew; Kandasamy, Arulmozhi D.; Pacher, Pal; Schulz, Richard

    2009-01-01

    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to determine MMP-2 activity we found that four PARP inhibitors (3-AB, PJ-34, 5-AIQ, and EB-47) inhibited 64 kDa MMP-2 in a concentration-dependent manner. The IC 50 values of PJ-34 and 5-AIQ were in the high micromolar range and comparable to those of known MMP-2 inhibitors doxycycline, minocycline or o-phenanthroline, whereas those for 3-AB and EB-47 were in the millimolar range. Co-incubation of PARP inhibitors with doxycycline showed an additive inhibition of MMP-2 that was significant for 3-AB alone. These data demonstrate that the protective effects of some PARP inhibitors may include inhibition of MMP-2 activity.

  19. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Nicolescu, Adrian C.; Holt, Andrew; Kandasamy, Arulmozhi D. [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada); Pacher, Pal [National Institutes of Health, NIAAA, Laboratory of Physiologic Studies, Bethesda, MD (United States); Schulz, Richard, E-mail: richard.schulz@ualberta.ca [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada)

    2009-10-02

    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to determine MMP-2 activity we found that four PARP inhibitors (3-AB, PJ-34, 5-AIQ, and EB-47) inhibited 64 kDa MMP-2 in a concentration-dependent manner. The IC{sub 50} values of PJ-34 and 5-AIQ were in the high micromolar range and comparable to those of known MMP-2 inhibitors doxycycline, minocycline or o-phenanthroline, whereas those for 3-AB and EB-47 were in the millimolar range. Co-incubation of PARP inhibitors with doxycycline showed an additive inhibition of MMP-2 that was significant for 3-AB alone. These data demonstrate that the protective effects of some PARP inhibitors may include inhibition of MMP-2 activity.

  20. Novel targeted therapeutics: inhibitors of MDM2, ALK and PARP

    Directory of Open Access Journals (Sweden)

    Hsueh Chung-Tsen

    2011-04-01

    Full Text Available Abstract We reviewed preclinical data and clinical development of MDM2 (murine double minute 2, ALK (anaplastic lymphoma kinase and PARP (poly [ADP-ribose] polymerase inhibitors. MDM2 binds to p53, and promotes degradation of p53 through ubiquitin-proteasome degradation. JNJ-26854165 and RO5045337 are 2 small-molecule inhibitors of MDM2 in clinical development. ALK is a transmembrane protein and a member of the insulin receptor tyrosine kinases. EML4-ALK fusion gene is identified in approximately 3-13% of non-small cell lung cancer (NSCLC. Early-phase clinical studies with Crizotinib, an ALK inhibitor, in NSCLC harboring EML4-ALK have demonstrated promising activity with high response rate and prolonged progression-free survival. PARPs are a family of nuclear enzymes that regulates the repair of DNA single-strand breaks through the base excision repair pathway. Randomized phase II study has shown adding PARP-1 inhibitor BSI-201 to cytotoxic chemotherapy improves clinical outcome in patients with triple-negative breast cancer. Olaparib, another oral small-molecule PARP inhibitor, demonstrated encouraging single-agent activity in patients with advanced breast or ovarian cancer. There are 5 other PARP inhibitors currently under active clinical investigation.

  1. Microarray-based screening of heat shock protein inhibitors.

    Science.gov (United States)

    Schax, Emilia; Walter, Johanna-Gabriela; Märzhäuser, Helene; Stahl, Frank; Scheper, Thomas; Agard, David A; Eichner, Simone; Kirschning, Andreas; Zeilinger, Carsten

    2014-06-20

    Based on the importance of heat shock proteins (HSPs) in diseases such as cancer, Alzheimer's disease or malaria, inhibitors of these chaperons are needed. Today's state-of-the-art techniques to identify HSP inhibitors are performed in microplate format, requiring large amounts of proteins and potential inhibitors. In contrast, we have developed a miniaturized protein microarray-based assay to identify novel inhibitors, allowing analysis with 300 pmol of protein. The assay is based on competitive binding of fluorescence-labeled ATP and potential inhibitors to the ATP-binding site of HSP. Therefore, the developed microarray enables the parallel analysis of different ATP-binding proteins on a single microarray. We have demonstrated the possibility of multiplexing by immobilizing full-length human HSP90α and HtpG of Helicobacter pylori on microarrays. Fluorescence-labeled ATP was competed by novel geldanamycin/reblastatin derivatives with IC50 values in the range of 0.5 nM to 4 μM and Z(*)-factors between 0.60 and 0.96. Our results demonstrate the potential of a target-oriented multiplexed protein microarray to identify novel inhibitors for different members of the HSP90 family. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Aromatic inhibitors derived from ammonia-pretreated lignocellulose hinder bacterial ethanologenesis by activating regulatory circuits controlling inhibitor efflux and detoxification

    Directory of Open Access Journals (Sweden)

    David H. Keating

    2014-08-01

    Full Text Available Efficient microbial conversion of lignocellulosic hydrolysates to biofuels is a key barrier to the economically viable deployment of lignocellulosic biofuels. A chief contributor to this barrier is the impact on microbial processes and energy metabolism of lignocellulose-derived inhibitors, including phenolic carboxylates, phenolic amides (for ammonia-pretreated biomass, phenolic aldehydes, and furfurals. To understand the bacterial pathways induced by inhibitors present in ammonia-pretreated biomass hydrolysates, which are less well studied than acid-pretreated biomass hydrolysates, we developed and exploited synthetic mimics of ammonia-pretreated corn stover hydrolysate (ACSH. To determine regulatory responses to the inhibitors normally present in ACSH, we measured transcript and protein levels in an Escherichia coli ethanologen using RNA-seq and quantitative proteomics during fermentation to ethanol of synthetic hydrolysates containing or lacking the inhibitors. Our study identified four major regulators mediating these responses, the MarA/SoxS/Rob network, AaeR, FrmR, and YqhC. Induction of these regulons was correlated with a reduced rate of ethanol production, buildup of pyruvate, depletion of ATP and NAD(PH, and an inhibition of xylose conversion. The aromatic aldehyde inhibitor 5-hydroxymethylfurfural appeared to be reduced to its alcohol form by the ethanologen during fermentation, whereas phenolic acid and amide inhibitors were not metabolized. Together, our findings establish that the major regulatory responses to lignocellulose-derived inhibitors are mediated by transcriptional rather than translational regulators, suggest that energy consumed for inhibitor efflux and detoxification may limit biofuel production, and identify a network of regulators for future synthetic biology efforts.

  3. Theoretical study on the interaction of pyrrolopyrimidine derivatives as LIMK2 inhibitors: insight into structure-based inhibitor design.

    Science.gov (United States)

    Shen, Mingyun; Zhou, Shunye; Li, Youyong; Li, Dan; Hou, Tingjun

    2013-10-01

    LIM kinases (LIMKs), downstream of Rho-associated protein kinases (ROCKs) and p21-activated protein kinases (PAKs), are shown to be promising targets for the treatment of cancers. In this study, the inhibition mechanism of 41 pyrrolopyrimidine derivatives as LIMK2 inhibitors was explored through a series of theoretical approaches. First, a model of LIMK2 was generated through molecular homology modeling, and the studied inhibitors were docked into the binding active site of LIMK2 by the docking protocol, taking into consideration the flexibility of the protein. The binding poses predicted by molecular docking for 17 selected inhibitors with different bioactivities complexed with LIMK2 underwent molecular dynamics (MD) simulations, and the binding free energies for the complexes were predicted by using the molecular mechanics/generalized born surface area (MM/GBSA) method. The predicted binding free energies correlated well with the experimental bioactivities (r(2) = 0.63 or 0.62). Next, the free energy decomposition analysis was utilized to highlight the following key structural features related to biological activity: (1) the important H-bond between Ile408 and pyrrolopyrimidine, (2) the H-bonds between the inhibitors and Asp469 and Gly471 which maintain the stability of the DFG-out conformation, and (3) the hydrophobic interactions between the inhibitors and several key residues (Leu337, Phe342, Ala345, Val358, Lys360, Leu389, Ile408, Leu458 and Leu472). Finally, a variety of LIMK2 inhibitors with a pyrrolopyrimidine scaffold were designed, some of which showed improved potency according to the predictions. Our studies suggest that the use of molecular docking with MD simulations and free energy calculations could be a powerful tool for understanding the binding mechanism of LIMK2 inhibitors and for the design of more potent LIMK2 inhibitors.

  4. Oral direct thrombin inhibitors or oral factor Xa inhibitors for the treatment of pulmonary embolism.

    Science.gov (United States)

    Robertson, Lindsay; Kesteven, Patrick; McCaslin, James E

    2015-12-04

    Pulmonary embolism is a potentially life-threatening condition in which a clot can travel from the deep veins, most commonly in the leg, up to the lungs. Previously, a pulmonary embolism was treated with the anticoagulants heparin and vitamin K antagonists. Recently, however, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTI) and oral factor Xa inhibitors. The new drugs have characteristics that may be favourable over conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or re-dosing and few known drug interactions. To date, no Cochrane review has measured the effectiveness and safety of these drugs in the long-term treatment (minimum duration of three months) of pulmonary embolism. To assess the effectiveness of oral DTIs and oral factor Xa inhibitors for the long-term treatment of pulmonary embolism. The Cochrane Vascular Trials Search Co-ordinator searched the Specialised Register (last searched January 2015) and the Cochrane Register of Studies (last searched January 2015). Clinical trials databases were also searched for details of ongoing or unpublished studies. We searched the reference lists of relevant articles retrieved by electronic searches for additional citations. We included randomised controlled trials in which patients with a pulmonary embolism confirmed by standard imaging techniques were allocated to receive an oral DTI or an oral factor Xa inhibitor for the long-term (minimum duration three months) treatment of pulmonary embolism. Two review authors (LR, JM) independently extracted the data and assessed the risk of bias in the trials. Any disagreements were resolved by discussion with the third author (PK). We used meta-analyses when we considered heterogeneity low. The two primary outcomes were recurrent venous thromboembolism and pulmonary embolism. Other outcomes included all-cause mortality and major bleeding. We calculated all outcomes

  5. Cardiovascular Disease After Aromatase Inhibitor Use.

    Science.gov (United States)

    Haque, Reina; Shi, Jiaxiao; Schottinger, Joanne E; Chung, Joanie; Avila, Chantal; Amundsen, Britta; Xu, Xiaoqing; Barac, Ana; Chlebowski, Rowan T

    2016-12-01

    Cardiovascular disease (CVD) is an important cause of death in older patients with breast cancer. However, limited information exists on the long-term effect of aromatase inhibitor (AI) use on CVD risk in breast cancer survivors. To this point, no other population-based studies have been able to adjust for CVD risk factors or cardiovascular medications. To determine the long-term influence of adjuvant endocrine therapies on CVD in a cohort of postmenopausal breast cancer survivors in analyses that accounted for major CVD risk factors, medication use, chemotherapy, and radiotherapy. A retrospective cohort of postmenopausal women with breast cancer diagnosed from January 1, 1991, to December 31, 2010, and followed up through December 31, 2011 (maximum, 21 years [72 886 person-years]), was evaluated using records from a managed care organization with nearly 20 community hospitals in California. A total of 13 273 postmenopausal women with hormone receptor-positive breast cancer without prior CVD were included. Cardiovascular disease incidence was compared across endocrine therapy categories. Information on demographics, comorbidity, medication, use, and CVD risk was captured from electronic health records. Multivariate Cox proportional hazards models using time-dependent endocrine drug use variables and propensity scores were conducted. Data analysis was conducted from September 15, 2014, to February 1, 2016. Women were grouped by endocrine therapy status (tamoxifen citrate only, AI only, both, or neither). Person-year rates of CVD for each therapy group. During 72 886 person-years in 13 273 women (mean [SD] age, 66.8 [8.1] years) with follow-up through 2011, we observed 3711 CVD events. In multivariable analyses (reported as hazard ratio [95% CI]), AI-only users had a similar risk of cardiac ischemia (myocardial infarction and angina) (adjusted, 0.97 [0.78-1.22]) and stroke (adjusted, 0.97 [0.70-1.33]) as tamoxifen-only users (reference). However, we found an

  6. Everolimus with reduced calcineurin inhibitor in thoracic transplant recipients with renal dysfunction: a multicenter, randomized trial

    DEFF Research Database (Denmark)

    Gullestad, Lars; Iversen, Martin; Mortensen, Svend-Aage

    2010-01-01

    The proliferation signal inhibitor everolimus offers the potential to reduce calcineurin inhibitor (CNI) exposure and alleviate CNI-related nephrotoxicity. Randomized trials in maintenance thoracic transplant patients are lacking.......The proliferation signal inhibitor everolimus offers the potential to reduce calcineurin inhibitor (CNI) exposure and alleviate CNI-related nephrotoxicity. Randomized trials in maintenance thoracic transplant patients are lacking....

  7. Effect of Wall Shear Stress on Corrosion Inhibitor Film Performance

    Science.gov (United States)

    Canto Maya, Christian M.

    In oil and gas production, internal corrosion of pipelines causes the highest incidence of recurring failures. Ensuring the integrity of ageing pipeline infrastructure is an increasingly important requirement. One of the most widely applied methods to reduce internal corrosion rates is the continuous injection of chemicals in very small quantities, called corrosion inhibitors. These chemical substances form thin films at the pipeline internal surface that reduce the magnitude of the cathodic and/or anodic reactions. However, the efficacy of such corrosion inhibitor films can be reduced by different factors such as multiphase flow, due to enhanced shear stress and mass transfer effects, loss of inhibitor due to adsorption on other interfaces such as solid particles, bubbles and droplets entrained by the bulk phase, and due to chemical interaction with other incompatible substances present in the stream. The first part of the present project investigated the electrochemical behavior of two organic corrosion inhibitors (a TOFA/DETA imidazolinium, and an alkylbenzyl dimethyl ammonium chloride), with and without an inorganic salt (sodium thiosulfate), and the resulting enhancement. The second part of the work explored the performance of corrosion inhibitor under multiphase (gas/liquid, solid/liquid) flow. The effect of gas/liquid multiphase flow was investigated using small and large scale apparatus. The small scale tests were conducted using a glass cell and a submersed jet impingement attachment with three different hydrodynamic patterns (water jet, CO 2 bubbles impact, and water vapor cavitation). The large scale experiments were conducted applying different flow loops (hilly terrain and standing slug systems). Measurements of weight loss, linear polarization resistance (LPR), and adsorption mass (using an electrochemical quartz crystal microbalance, EQCM) were used to quantify the effect of wall shear stress on the performance and integrity of corrosion inhibitor

  8. Congenital ventricular septal defects and prenatal exposure to cyclooxygenase inhibitors

    Directory of Open Access Journals (Sweden)

    F. Burdan

    2006-07-01

    Full Text Available Ventricular septal defects (VSDs are common congenital abnormalities which have been reported to be associated with maternal fever and various environmental factors. The aim of the present study was to evaluate the effect of prenatal exposure to cyclooxygenase (COX inhibitors on heart defects. A retrospective statistical analysis was performed using data collected in our laboratory during various teratological studies carried out on albino CRL:(WIWUBR Wistar strain rats from 1997 to 2004. The observations were compared with concurrent and historic control data, as well as findings from other developmental toxicological studies with selective and nonselective COX-2 inhibitors. Despite the lack of significant differences in the frequency of VSDs between drug-exposed and control groups, statistical analysis by the two-sided Mantel-Haenszel test and historical control data showed a higher incidence of heart defects in offspring exposed to nonselective COX inhibitors (30.06/10,000. Unlike other specific inhibitors, aspirin (46.26/10,000 and ibuprofen (106.95/10,000 significantly increased the incidence of the VSD when compared with various control groups (5.38-19.72/10,000. No significant differences in length or weight were detected between fetuses exposed to COX inhibitors and born with VSD and non-malformed offsprings. However, a statistically significant increase of fetal body length and decrease of body mass index were found in fetuses exposed to COX inhibitors when compared with untreated control. We conclude that prenatal exposure to COX inhibitors, especially aspirin and ibuprofen, increased the incidence of VSDs in rat offspring but was not related to fetal growth retardation.

  9. A bioavailable cathepsin S nitrile inhibitor abrogates tumor development.

    Science.gov (United States)

    Wilkinson, Richard D A; Young, Andrew; Burden, Roberta E; Williams, Rich; Scott, Christopher J

    2016-04-21

    Cathepsin S has been implicated in a variety of malignancies with genetic ablation studies demonstrating a key role in tumor invasion and neo-angiogenesis. Thus, the application of cathepsin S inhibitors may have clinical utility in the treatment of cancer. In this investigation, we applied a cell-permeable dipeptidyl nitrile inhibitor of cathepsin S, originally developed to target cathepsin S in inflammatory diseases, in both in vitro and in vivo tumor models. Validation of cathepsin S selectivity was carried out by assaying fluorogenic substrate turnover using recombinant cathepsin protease. Complete kinetic analysis was carried out and true K i values calculated. Abrogation of tumour invasion using murine MC38 and human MCF7 cell lines were carried out in vitro using a transwell migration assay. Effect on endothelial tube formation was evaluated using primary HUVEC cells. The effect of inhibitor in vivo on MC38 and MCF7 tumor progression was evaluated using cells propagated in C57BL/6 and BALB/c mice respectively. Subsequent immunohistochemical staining of proliferation (Ki67) and apoptosis (TUNEL) was carried out on MCF7 tumors. We confirmed that this inhibitor was able to selectively target cathepsin S over family members K, V, L and B. The inhibitor also significantly reduced MC38 and MCF7 cell invasion and furthermore, significantly reduced HUVEC endothelial tubule formation in vitro. In vivo analysis revealed that the compound could significantly reduce tumor volume in murine MC38 syngeneic and MCF7 xenograft models. Immunohistochemical analysis of MCF7 tumors revealed cathepsin S inhibitor treatment significantly reduced proliferation and increased apoptosis. In summary, these results highlight the characterisation of this nitrile cathepsin S inhibitor using in vitro and in vivo tumor models, presenting a compound which may be used to further dissect the role of cathepsin S in cancer progression and may hold therapeutic potential.

  10. [The primary structure of the alpha-amylase inhibitor Hoe 467A from Streptomyces tendae 4158. A new class of inhibitors].

    Science.gov (United States)

    Aschauer, H; Vértesy, L; Nesemann, G; Braunitzer, G

    1983-10-01

    The native or modified alpha-amylase inhibitor Hoe 467A - isolated from the culture medium of Streptomyces tendae 4158 - and overlapping peptides were degraded by the automatic Edman technique. The oxidized or aminoethylated or oxidized and maleoylated inhibitor was digested with trypsin and the native inhibitor with pepsin. Further digestion with Staphylococcus aureus proteinase was also carried out. After peptic digestion two cystin peptides were isolated, which allowed the establishment of the disulfide bonds. The alpha-amylase inhibitor is a polypeptid consisting of 74 amino-acid residues with a molecular mass of 7958 Da. The inhibitor is composed of all naturally occurring amino acids except methionine and phenylalanine and shows no sequence homology to known inhibitors. The clinical and pharmacological importance in respect to the inhibitors ability for inactivation of human salivary and pancreatic alpha-amylase is discussed. Especially the proteinase resistance of the inhibitor enables a clinical application in human (e.g. Diabetes mellitus) per os.

  11. Localization to Chromosomes of Structural Genes for the Major Protease Inhibitors of Barley Grains

    DEFF Research Database (Denmark)

    Hejgaard, Jørn; Bjørn, S.E.; Nielsen, Gunnar Gissel

    1984-01-01

    Wheat-barley chromosome addition lines were compared by isoelectric focusing of protein extracts to identify chromosomes carrying loci for the major immunochemically distinct protease inhibitors of barley grains. Structural genes for the following inhibitors were localized: an inhibitor of both...... endogenous α-amylase 2 and subtilisin (ASI) on chromosome 2, two chymotrypsin/subtilisin inhibitors (CI-1 and CI-2) on chromosome 5 (long arm) and the major trypsin inhibitor (TI-1) on chromosome 3....

  12. Effect of the scale inhibitor on ion content in reverse osmosis system for seawater desalination

    Science.gov (United States)

    Gao, Yuhua; Liu, Zhenfa; Zhang, Lihui; Li, Haihua

    2017-09-01

    A scale inhibitor was synthesized from polysuccinimide with 2-aminoethanesulfonic acid and aspartic acid. The effect of scale inhibitor on ion content in reverse osmosis system for seawater desalination was studied. The results showed that the ion content of permeate water is lower with the scale inhibitor added in RO system for seawater desalination than without scale inhibitor. On the contrary, the ion content of concentrate water is higher when with scale inhibitor in RO system.

  13. The Nonglycemic Actions of Dipeptidyl Peptidase-4 Inhibitors

    Directory of Open Access Journals (Sweden)

    Na-Hyung Kim

    2014-01-01

    Full Text Available A cell surface serine protease, dipeptidyl peptidase 4 (DPP-4, cleaves dipeptide from peptides containing proline or alanine in the N-terminal penultimate position. Two important incretin hormones, glucagon-like peptide-1 (GLP-1 and glucose-dependent insulinotropic peptide (GIP, enhance meal-stimulated insulin secretion from pancreatic β-cells, but are inactivated by DPP-4. Diabetes and hyperglycemia increase the DPP-4 protein level and enzymatic activity in blood and tissues. In addition, multiple other functions of DPP-4 suggest that DPP-4 inhibitor, a new class of antidiabetic agents, may have pleiotropic effects. Studies have shown that DPP-4 itself is involved in the inflammatory signaling pathway, the stimulation of vascular smooth cell proliferation, and the stimulation of oxidative stress in various cells. DPP-4 inhibitor ameliorates these pathophysiologic processes and has been shown to have cardiovascular protective effects in both in vitro and in vivo experiments. However, in recent randomized clinical trials, DPP-4 inhibitor therapy in high risk patients with type 2 diabetes did not show cardiovascular protective effects. Some concerns on the actions of DPP-4 inhibitor include sympathetic activation and neuropeptide Y-mediated vascular responses. Further studies are required to fully characterize the cardiovascular effects of DPP-4 inhibitor.

  14. Health economics of treating haemophilia A with inhibitors.

    Science.gov (United States)

    Knight, C

    2005-11-01

    Haemophilia is a rare, inherited blood disorder in which blood clotting is impaired such that patients suffer from excessive internal and external bleeding. At present there is no cure for haemophilia A and patients require expensive, life-long treatment involving clotting factor replacement therapy. Treatment costs are perceived to be higher for patients who have developed inhibitory antibodies to factor VIII, the standard therapy for haemophilia A. However, initial cost analyses suggest that clotting factor therapy with alternative haemostatic agents, such as recombinant activated factor VII or activated prothrombin complex concentrate, is no more expensive for the majority of haemophilia A patients with inhibitors than for those without inhibitors. With the availability of effective alternative haemostatic agents, orthopaedic surgery for haemophilia A patients with inhibitors is now a clinical option, and initial cost analyses suggest this may be a cost-effective treatment strategy for patients with inhibitors whose quality of life (QoL) is severely impaired by joint arthropathy. In an era of finite healthcare resourcing it is important to determine whether new treatments justify higher unit costs compared with standard therapies and whether such higher costs are justified from an individual perspective in terms of improved QoL, and from a societal perspective in terms of improved productivity and reduced overall healthcare costs. This paper examines current data on the health economics of treating haemophilia A patients with inhibitors, focusing on the overall costs of clotting factor replacement therapy and the cost consequences of joint replacement.

  15. SGLT2 Inhibitors as a Therapeutic Option for Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Daiji Kawanami

    2017-05-01

    Full Text Available Diabetic nephropathy (DN is a major cause of end-stage renal disease (ESRD worldwide. Glycemic and blood pressure (BP control are important but not sufficient to attenuate the incidence and progression of DN. Sodium–glucose cotransporter (SGLT 2 inhibitors are a new class of glucose-lowering agent suggested to exert renoprotective effects in glucose lowering-dependent and independent fashions. Experimental studies have shown that SGLT2 inhibitors attenuate DN in animal models of both type 1 diabetes (T1D and type 2 diabetes (T2D, indicating a potential renoprotective effect beyond glucose reduction. Renoprotection by SGLT2 inhibitors has been demonstrated in T2D patients with a high cardiovascular risk in randomized controlled trials (RCTs. These favorable effects of SGLT2 inhibitors are explained by several potential mechanisms, including the attenuation of glomerular hyperfiltration, inflammation and oxidative stress. In this review article, we discuss the renoprotective effects of SGLT2 inhibitors by integrating experimental findings with the available clinical data.

  16. Cardiovascular effects of sodium glucose cotransporter 2 inhibitors

    Science.gov (United States)

    Cavaiola, Tricia Santos; Pettus, Jeremy

    2018-01-01

    As the first cardiovascular (CV) outcome trial of a glucose-lowering agent to demonstrate a reduction in the risk of CV events in patients with type 2 diabetes mellitus (T2DM), the EMPAgliflozin Removal of Excess Glucose: Cardiovascular OUTCOME Event Trial in Type 2 Diabetes Mellitus Patients (EMPA-REG OUTCOME®) trial, which investigated the sodium glucose cotransporter 2 (SGLT2) inhibitor empagliflozin, has generated great interest among health care professionals. CV outcomes data for another SGLT2 inhibitor, canagliflozin, have been published recently in the CANagliflozin CardioVascular Assessment Study (CANVAS) Program, as have CV data from the retrospective real-world study Comparative Effectiveness of Cardiovascular Outcomes in New Users of Sodium-Glucose Cotransporter-2 Inhibitors (CVD-REAL), which compared SGLT2 inhibitors with other classes of glucose-lowering drugs. This review discusses the results of these three studies and, with a focus on EMPA-REG OUTCOME, examines the possible mechanisms by which SGLT2 inhibitors may reduce CV risk in patients with T2DM. PMID:29695924

  17. SGLT2 Inhibitors as a Therapeutic Option for Diabetic Nephropathy.

    Science.gov (United States)

    Kawanami, Daiji; Matoba, Keiichiro; Takeda, Yusuke; Nagai, Yosuke; Akamine, Tomoyo; Yokota, Tamotsu; Sango, Kazunori; Utsunomiya, Kazunori

    2017-05-18

    Diabetic nephropathy (DN) is a major cause of end-stage renal disease (ESRD) worldwide. Glycemic and blood pressure (BP) control are important but not sufficient to attenuate the incidence and progression of DN. Sodium-glucose cotransporter (SGLT) 2 inhibitors are a new class of glucose-lowering agent suggested to exert renoprotective effects in glucose lowering-dependent and independent fashions. Experimental studies have shown that SGLT2 inhibitors attenuate DN in animal models of both type 1 diabetes (T1D) and type 2 diabetes (T2D), indicating a potential renoprotective effect beyond glucose reduction. Renoprotection by SGLT2 inhibitors has been demonstrated in T2D patients with a high cardiovascular risk in randomized controlled trials (RCTs). These favorable effects of SGLT2 inhibitors are explained by several potential mechanisms, including the attenuation of glomerular hyperfiltration, inflammation and oxidative stress. In this review article, we discuss the renoprotective effects of SGLT2 inhibitors by integrating experimental findings with the available clinical data.

  18. Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jiyoun [Sungshin Women' s Univ., Seoul (Korea, Republic of)

    2012-04-15

    We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry.

  19. Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

    International Nuclear Information System (INIS)

    Lee, Jiyoun

    2012-01-01

    We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry

  20. HDAC inhibitors: modulating leukocyte differentiation, survival, proliferation and inflammation.

    Science.gov (United States)

    Sweet, Matthew J; Shakespear, Melanie R; Kamal, Nabilah A; Fairlie, David P

    2012-01-01

    Therapeutic effects of histone deacetylase (HDAC) inhibitors in cancer models were first linked to their ability to cause growth arrest and apoptosis of tumor cells. It is now clear that these agents also have pleiotropic effects on angiogenesis and the immune system, and some of these properties are likely to contribute to their anti-cancer activities. It is also emerging that inhibitors of specific HDACs affect the differentiation, survival and/or proliferation of distinct immune cell populations. This is true for innate immune cells such as macrophages, as well as cells of the acquired immune system, for example, T-regulatory cells. These effects may contribute to therapeutic profiles in some autoimmune and chronic inflammatory disease models. Here, we review our current understanding of how classical HDACs (HDACs 1-11) and their inhibitors impact on differentiation, survival and proliferation of distinct leukocyte populations, as well as the likely relevance of these effects to autoimmune and inflammatory disease processes. The ability of HDAC inhibitors to modulate leukocyte survival may have implications for the rationale of developing selective inhibitors as anti-inflammatory drugs.

  1. Studies on terrein as a new class of proteasome inhibitors

    International Nuclear Information System (INIS)

    Demasi, M.; Felicio, A.L.; Lima, C.; Pacheco, A.O.; Leite, H.G.; Andrade, L.H.

    2010-01-01

    The proteasome is an intracellular multicatalytic protease involved in the cell cycle regulation, signaling response, antigen presentation and apoptosis. Since proteasome inhibitors promote cell death by apoptosis, they have been proposed as new anti-tumoral drugs. Terrein, a secondary metabolite secreted by the fungus Aspergillus terreus, was firstly described in 1935. In the present work we report that terrein isolated through the screening for inhibitors of the 20S proteasome showed inhibitory effect upon both chymotrypsin- and trypsin-like activities of the multicatalytic core particle, the 20S proteasome. Despite of the high inhibitory concentration determined in vitro, that verified by incubating cells (fibroblasts and a pulmonary tumor cell line) in the presence of terrein was 4-fold lower indicating the proteasome as a selective intracellular target. Moreover, terrein promoted apoptotic cell death on both fibroblasts and pulmonary tumor cell line tested. Although terrein concentrations (mM range) necessary to elicit apoptosis in the cellular models herein tried were high when compared to those (muM and nM range) of other inhibitors recently described, its chemical structure is not correlated to any other inhibitor reported thus far. Therefore, the present results point out for the possibility of exploring terrein as a new molecular fragment for the development of synthetic proteasome inhibitors. (author)

  2. Characterization of Encapsulated Corrosion Inhibitors for Environmentally Friendly Smart Coatings

    Science.gov (United States)

    Pearman, B. P.; Calle, L. M.; Zhang, X.; Li, W.; Buhrow, J. W.; Johnsey, M. N.; Montgomery, E. L.; Fitzpatrick, L.; Surma, J. M.

    2015-01-01

    The NASA Kennedy Space Center's Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion indicators, inhibitors and self-healing agents. This allows the incorporation of autonomous corrosion control functionalities, such as corrosion detection and inhibition as well as the self-healing of mechanical damage, into coatings. This paper presents technical details on the characterization of inhibitor-containing particles and their corrosion inhibitive effects using electrochemical and mass loss methods. Three organic environmentally friendly corrosion inhibitors were encapsulated in organic microparticles that are compatible with desired coatings. The release of the inhibitors from the microparticles in basic solution was studied. Fast release, for immediate corrosion protection, as well as long-term release for continued protection, was observed. The inhibition efficacy of the inhibitors, incorporated directly and in microparticles, on carbon steel was evaluated. Polarization curves and mass loss measurements showed that, in the case of 2MBT, its corrosion inhibition effectiveness was greater when it was delivered from microparticles.

  3. [Pharmacogenic osteoporosis beyond cortisone. Proton pump inhibitors, glitazones and diuretics].

    Science.gov (United States)

    Kann, P H; Hadji, P; Bergmann, R S

    2014-05-01

    [corrected] There are many drugs which can cause osteoporosis or at least favor its initiation. The effect of hormones and drugs with antihormonal activity, such as glucocorticoids and aromatase inhibitors, on initiation of osteoporosis is well known. In addition, proton pump inhibitors, glitazones and diuretics also influence the formation of osteoporosis. The results of currently available studies on the correlation between proton pump inhibitors, glitazones and diuretics on formation of osteoporosis were evaluated and summarized. Proton pump inhibitors and glitazones increase the risk for osteoporotic fractures. Loop diuretics may slightly increase fracture risk, whereas thiazides were shown to be osteoprotective by reducing fracture probability on a relevant scale. Proton pump inhibitors should not be prescribed without serious consideration and then only as long as necessary. Alternatively, the administration of the less effective H2 antagonists should be considered when possible due to the reduction of acid secretion. Because the long-term intake of thiazides is associated with a clinically relevant reduction in the risk of fractures and they are economic and well-tolerated, prescription can be thoroughly recommended within the framework of differential diagnostic considerations in an appropriate clinical context. The briefly increased risk of falling immediately after starting diuretic therapy is the only point which needs to be considered.

  4. Antitumour agents as inhibitors of tryptophan 2,3-dioxygenase

    Energy Technology Data Exchange (ETDEWEB)

    Pantouris, Georgios; Mowat, Christopher G., E-mail: C.G.Mowat@ed.ac.uk

    2014-01-03

    Highlights: •∼2800 National Cancer Institute USA compounds have been screened as potential inhibitors of TDO and/or IDO. •Seven compounds with anti-tumour properties have been identified as potent inhibitors. •NSC 36398 (taxifolin, dihydroquercetin) is selective for TDO with a K{sub i} of 16 M. •This may help further our understanding of the role of TDO in cancer. -- Abstract: The involvement of tryptophan 2,3-dioxygenase (TDO) in cancer biology has recently been described, with the enzyme playing an immunomodulatory role, suppressing antitumour immune responses and promoting tumour cell survival and proliferation. This finding reinforces the need for specific inhibitors of TDO that may potentially be developed for therapeutic use. In this work we have screened ∼2800 compounds from the library of the National Cancer Institute USA and identified seven potent inhibitors of TDO with inhibition constants in the nanomolar or low micromolar range. All seven have antitumour properties, killing various cancer cell lines. For comparison, the inhibition potencies of these compounds were tested against IDO and their inhibition constants are reported. Interestingly, this work reveals that NSC 36398 (dihydroquercetin, taxifolin), with an in vitro inhibition constant of ∼16 μM, is the first TDO-selective inhibitor reported.

  5. Substrate and inhibitor specificity of kynurenine monooxygenase from Cytophaga hutchinsonii.

    Science.gov (United States)

    Phillips, Robert S; Anderson, Andrew D; Gentry, Harvey G; Güner, Osman F; Bowen, J Phillip

    2017-04-15

    Kynurenine monooxygenase (KMO) is a potential drug target for treatment of neurodegenerative disorders such as Huntington's and Alzheimer's diseases. We have evaluated substituted kynurenines as substrates or inhibitors of KMO from Cytophaga hutchinsonii. Kynurenines substituted with a halogen at the 5-position are excellent substrates, with values of k cat and k cat /K m comparable to or higher than kynurenine. However, kynurenines substituted in the 3-position are competitive inhibitors, with K I values lower than the K m for kynurenine. Bromination also enhances inhibition, and 3,5-dibromokynurenine is a potent competitive inhibitor with a K I value of 1.5μM. A pharmacophore model of KMO was developed, and predicted that 3,4-dichlorohippuric acid would be an inhibitor. The K I for this compound was found to be 34μM, thus validating the pharmacophore model. We are using these results and our model to design more potent inhibitors of KMO. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Clinical trials for BET inhibitors run ahead of the science.

    Science.gov (United States)

    Andrieu, Guillaume; Belkina, Anna C; Denis, Gerald V

    2016-03-01

    Several cancer clinical trials for small molecule inhibitors of BET bromodomain proteins have been initiated. There is enthusiasm for the anti-proliferative effect of inhibiting BRD4, one of the targets of these inhibitors, which is thought to cooperate with MYC, a long-desired target for cancer therapeutics. However, no current inhibitor is selective for BRD4 among the three somatic BET proteins, which include BRD2 and BRD3; their respective functions are partially overlapping and none are functionally redundant with BRD4. Each BET protein controls distinct transcriptional pathways that are important for functions beyond cancer cell proliferation, including insulin production, cytokine gene transcription, T cell differentiation, adipogenesis and most seriously, active repression of dangerous latent viruses like HIV. BET inhibitors have been shown to reactivate HIV in human cells. Failure to appreciate that at concentrations used, no available BET inhibitor is member-selective, or to develop a sound biological basis to understand the diverse functions of BET proteins before undertaking for these clinical trials is reckless and likely to lead to adverse events. More mechanistic information from new basic science studies should enable proper focus on the most relevant cancers and define the expected side effect profiles. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Renal Effects of DPP-4 Inhibitors: A Focus on Microalbuminuria

    Directory of Open Access Journals (Sweden)

    Martin Haluzík

    2013-01-01

    Full Text Available Incretin-based therapies represent one of the most promising options in type 2 diabetes treatment owing to their good effectiveness with low risk of hypoglycemia and no weight gain. Other numerous potential beneficial effects of incretin-based therapies have been suggested based mostly on experimental and small clinical studies including its beta-cell- and vasculo-protective actions. One of the recently emerged interesting features of dipeptidyl peptidase-4 (DPP-4 inhibitors is its possible protective effect on the diabetic kidney disease. Here, we review the renal effects of DPP-4 inhibitors with special focus on its influence on the onset and progression of microalbuminuria, as presence of microalbuminuria represents an important early sign of kidney damage and is also associated with increased risk of hypoglycemia and cardiovascular complications. Mechanisms underlying possible nephroprotective properties of DPP-4 inhibitors include reduction of oxidative stress and inflammation and improvement of endothelial dysfunction. Effects of DPP-4 inhibitors may be both glucagon-like peptide-1 (GLP-1 dependent and independent. Ongoing prospective studies focused on the nephroprotective effects of DPP-4 inhibitors will further clarify its possible role in the prevention/attenuation of diabetic kidney disease beyond its glucose lowering properties.

  8. Structural Principles in the Development of Cyclic Peptidic Enzyme Inhibitors

    Science.gov (United States)

    Xu, Peng; Andreasen, Peter A.; Huang, Mingdong

    2017-01-01

    This review summarizes our studies in the development of small cyclic peptides for specifically modulating enzyme activity. Serine proteases share highly similar active sites but perform diverse physiological and pathological functions. From a phage-display peptide library, we isolated two mono-cyclic peptides, upain-1 (CSWRGLENHRMC) and mupain-1 (CPAYSRYLDC), which inhibit the activity of human and murine urokinase-type plasminogen activators (huPA and muPA) with Ki values in the micromolar or sub-micromolar range, respectively. The following affinity maturations significantly enhanced the potencies of the two peptides, 10-fold and >250-fold for upain-1 and mupain-1, respectively. The most potent muPA inhibitor has a potency (Ki = 2 nM) and specificity comparable to mono-clonal antibodies. Furthermore, we also found an unusual feature of mupain-1 that its inhibitory potency can be enhanced by increasing the flexibility, which challenges the traditional viewpoint that higher rigidity leading to higher affinity. Moreover, by changing a few key residues, we converted mupain-1 from a uPA inhibitor to inhibitors of other serine proteases, including plasma kallikrein (PK) and coagulation factor XIa (fXIa). PK and fXIa inhibitors showed Ki values in the low nanomolar range and high specificity. Our studies demonstrate the versatility of small cyclic peptides to engineer inhibitory potency against serine proteases and to provide a new strategy for generating peptide inhibitors of serine proteases. PMID:29104489

  9. Novel β-amyloid aggregation inhibitors possessing a turn mimic.

    Science.gov (United States)

    Hamada, Yoshio; Miyamoto, Naoko; Kiso, Yoshiaki

    2015-04-01

    Amyloid β peptide, the main component of senile plaques found in the brain of Alzheimer disease (AD) patients, is a molecular target for AD therapeutic intervention. A number of potential AD therapeutics have been reported, including inhibitors of β-secretase, γ-secretase, and Aβ aggregation, and anti-amyloid agents, such as neprilysin, insulin degrading enzyme (IDE), and Aβ antibodies. Recently, we reported potent small-sized β-secretase (BACE1) inhibitors, which could serve as anti-AD drugs. However AD is a progressive disorder, where dementia symptoms gradually worsen over several decades, and therefore may require many years to get cured. One possible way to achieve a greater therapeutic effect is through simultaneous administration of multiple drugs, similar to those used in Highly Active Anti-Retroviral Therapy (HAART) used to treat AIDS. In order to overcome AD, we took a drug discovery approach to evaluate, novel β-amyloid aggregation inhibitors. Previously, we reported that a tong-type compound possessing a turn mimic as the inhibitor of HIV-1 protease dimerization. Oligomerized amyloid β peptides contain a turn structure within the molecule. Here, we designed and synthesized novel β-amyloid aggregation inhibitors with a turn-mimic template, based on the turn conformer of the oligomerized amyloid β peptides. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. 5 alpha-reductase inhibitors and prostatic disease.

    Science.gov (United States)

    Schröder, F H

    1994-08-01

    5 alpha-Reductase inhibitors are a new class of substances with very specific effects on type I and type II 5 alpha R which may be of use in the treatment of skin disease, such as male pattern baldness, male acne and hirsutism, as well as prostatic hyperplasia and prostate cancer. At least two types of 5 alpha R inhibitors with a different pH optimum have been described. cDNA encoding for both the type I and the type II enzyme has been cloned. Most of the orally effective 5 alpha R inhibitors belong to the class of 4-azasteroids. The radical substituted in the 17 position of the steroid ring seems to be related to species specific variations and to the types of 5 alpha R enzymes in different species and organ systems. 5 alpha R inhibitors lead to a decrease of plasma DHT by about 65% while there is a slight rise in plasma testosterone. The decrease of tissue DHT in the ventral prostate of the intact rat, the dog and in humans is more pronounced and amounts to about 85%. There is a reciprocal rise of tissue T in these systems. The application of an inhibitor of 5 alpha R type II leads to a shrinkage of BPH in men by about 30%. In the rat a similar shrinkage accompanied by a significant decrease of total organ DNA occurs. This decrease, however, is not as pronounced as can be achieved with castration.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Kinetic characterization of ebselen, chelerythrine and apomorphine as glutaminase inhibitors.

    Science.gov (United States)

    Thomas, Ajit G; Rojas, Camilo; Tanega, Cordelle; Shen, Min; Simeonov, Anton; Boxer, Matthew B; Auld, Douglas S; Ferraris, Dana V; Tsukamoto, Takashi; Slusher, Barbara S

    2013-08-23

    Glutaminase catalyzes the hydrolysis of glutamine to glutamate and plays a central role in the proliferation of neoplastic cells via glutaminolysis, as well as in the generation of excitotoxic glutamate in central nervous system disorders such as HIV-associated dementia (HAD) and multiple sclerosis. Both glutaminase siRNA and glutaminase inhibition have been shown to be effective in in vitro models of cancer and HAD, suggesting a potential role for small molecule glutaminase inhibitors. However, there are no potent, selective inhibitors of glutaminase currently available. The two prototypical glutaminase inhibitors, BPTES and DON, are either insoluble or non-specific. In a search for more drug-like glutaminase inhibitors, we conducted a screen of 1280 in vivo active drugs (Library of Pharmacologically Active Compounds (LOPAC(1280))) and identified ebselen, chelerythrine and (R)-apomorphine. The newly identified inhibitors exhibited 10 to 1500-fold greater affinities than DON and BPTES and over 100-fold increased efficiency of inhibition. Although non-selective, it is noteworthy that the affinity of ebselen for glutaminase is more potent than any other activity yet described. It is possible that the previously reported biological activity seen with these compounds is due, in part, to glutaminase inhibition. Ebselen, chelerythrine and apomorphine complement the armamentarium of compounds to explore the role of glutaminase in disease. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. A Pan-GTPase Inhibitor as a Molecular Probe.

    Directory of Open Access Journals (Sweden)

    Lin Hong

    Full Text Available Overactive GTPases have often been linked to human diseases. The available inhibitors are limited and have not progressed far in clinical trials. We report here a first-in-class small molecule pan-GTPase inhibitor discovered from a high throughput screening campaign. The compound CID1067700 inhibits multiple GTPases in biochemical, cellular protein and protein interaction, as well as cellular functional assays. In the biochemical and protein interaction assays, representative GTPases from Rho, Ras, and Rab, the three most generic subfamilies of the GTPases, were probed, while in the functional assays, physiological processes regulated by each of the three subfamilies of the GTPases were examined. The chemical functionalities essential for the activity of the compound were identified through structural derivatization. The compound is validated as a useful molecular probe upon which GTPase-targeting inhibitors with drug potentials might be developed.

  13. SGLT2 inhibitors: their potential reduction in blood pressure.

    Science.gov (United States)

    Maliha, George; Townsend, Raymond R

    2015-01-01

    The sodium glucose co-transporter 2 (SGLT2) inhibitors represent a promising treatment option for diabetes and its common comorbidity, hypertension. Emerging data suggests that the SGLT2 inhibitors provide a meaningful reduction in blood pressure, although the precise mechanism of the blood pressure drop remains incompletely elucidated. Based on current data, the blood pressure reduction is partially due to a combination of diuresis, nephron remodeling, reduction in arterial stiffness, and weight loss. While current trials are underway focusing on cardiovascular endpoints, the SGLT2 inhibitors present a novel treatment modality for diabetes and its associated hypertension as well as an opportunity to elucidate the pathophysiology of hypertension in diabetes. Copyright © 2015 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

  14. MEK Inhibitors Reverse cAMP-Mediated Anxiety in Zebrafish

    DEFF Research Database (Denmark)

    Lundegaard, Pia R.; Anastasaki, Corina; Grant, Nicola J.

    2015-01-01

    Altered phosphodiesterase (PDE)-cyclic AMP (cAMP) activity is frequently associated with anxiety disorders, but current therapies act by reducing neuronal excitability rather than targeting PDE-cAMP-mediated signaling pathways. Here, we report the novel repositioning of anti-cancer MEK inhibitors...... as anxiolytics in a zebrafish model of anxiety-like behaviors. PDE inhibitors or activators of adenylate cyclase cause behaviors consistent with anxiety in larvae and adult zebrafish. Small-molecule screening identifies MEK inhibitors as potent suppressors of cAMP anxiety behaviors in both larvae and adult...... zebrafish, while causing no anxiolytic behavioral effects on their own. The mechanism underlying cAMP-induced anxiety is via crosstalk to activation of the RAS-MAPK signaling pathway. We propose that targeting crosstalk signaling pathways can be an effective strategy for mental health disorders, and advance...

  15. Identification and detoxification of glycolaldehyde, an unattended bioethanol fermentation inhibitor.

    Science.gov (United States)

    Jayakody, Lahiru N; Ferdouse, Jannatul; Hayashi, Nobuyuki; Kitagaki, Hiroshi

    2017-03-01

    Although there have been approximately 60 chemical compounds identified as potent fermentation inhibitors in lignocellulose hydrolysate, our research group recently discovered glycolaldehyde as a key fermentation inhibitor during second generation biofuel production. Accordingly, we have developed a yeast S. cerevisiae strain exhibiting tolerance to glycolaldehyde. During this glycolaldehyde study, we established novel approaches for rational engineering of inhibitor-tolerant S. cerevisiae strains, including engineering redox cofactors and engineering the SUMOylation pathway. These new technical dimensions provide a novel platform for engineering S. cerevisiae strains to overcome one of the key barriers for industrialization of lignocellulosic ethanol production. As such, this review discusses novel biochemical insight of glycolaldehyde in the context of the biofuel industry.

  16. Laboratory study of reinforcement protection with corrosion inhibitors

    International Nuclear Information System (INIS)

    Stefanescu, D.; Mihalache, M.; Mogosan, S.

    2013-01-01

    Concrete is a durable material and its performance as part of the containment function in NPPs has been good. However, experience shows that degradation of the reinforced concrete structures caused by the corrosion of the reinforcing steel represents more than 80% of all damages in the world. Much effort has been made to develop a corrosion inhibition process to prolong the life of existing structures and minimize corrosion damages in new structures. Migrating Corrosion Inhibitor technology was developed to protect the embedded steel rebar/concrete structure. These inhibitors can be incorporated as an admixture or can be surface impregnated on existing concrete structures. The effectiveness of two inhibitors (ethanolamine and diethanolamine) mixed in the reinforced concrete was evaluated by gravimetric measurements. The corrosion behavior of the steel rebar and the inhibiting effects of the amino alcohol chemistry in an aggressive environment were monitored using electrochemical measurements and scanning electron microscopy (SEM) investigations. (authors)

  17. Seizure following the Use of the COX-2 Inhibitor Etoricoxib

    Directory of Open Access Journals (Sweden)

    Valentina Arnao

    2017-01-01

    Full Text Available We describe a case of epileptic seizures occurring after the use of a COX-2 inhibitor. A 61-year-old man was admitted to our department because of a generalized tonic-clonic seizure. EEG showed generalized slowdown of the activity. Neuroimaging and blood samples studies did not evidence alterations, but a careful pharmacological history revealed that the patient had taken the COX-2 inhibitor etoricoxib to treat lumbago few days before the onset of clinical symptoms. No seizures were reported after etoricoxib discontinuation and an EEG resulted to be normal two months after this. Conclusion. Knowing the pharmacological history of a patient is important for understanding the clinical presentation and selecting appropriate treatment. This is, to the best of our knowledge, the first reported case of generalized seizures associated with the use of COX-2 inhibitors.

  18. 4-Hydroxyphenylpyruvate Dioxygenase Inhibitors: From Chemical Biology to Agrochemicals.

    Science.gov (United States)

    Ndikuryayo, Ferdinand; Moosavi, Behrooz; Yang, Wen-Chao; Yang, Guang-Fu

    2017-10-04

    The development of new herbicides is receiving considerable attention to control weed biotypes resistant to current herbicides. Consequently, new enzymes are always desired as targets for herbicide discovery. 4-Hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) is an enzyme engaged in photosynthetic activity and catalyzes the transformation of 4-hydroxyphenylpyruvic acid (HPPA) into homogentisic acid (HGA). HPPD inhibitors constitute a promising area of discovery and development of innovative herbicides with some advantages, including excellent crop selectivity, low application rates, and broad-spectrum weed control. HPPD inhibitors have been investigated for agrochemical interests, and some of them have already been commercialized as herbicides. In this review, we mainly focus on the chemical biology of HPPD, discovery of new potential inhibitors, and strategies for engineering transgenic crops resistant to current HPPD-inhibiting herbicides. The conclusion raises some relevant gaps for future research directions.

  19. Biosensors for the determination of environmental inhibitors of enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Evtugyn, Gennadii A; Budnikov, Herman C [Kazan State University, Kazan (Russian Federation); Nikolskaya, Elena B [I.M. Sechenov Institute of Evolution Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg (Russian Federation)

    1999-12-31

    Characteristic features of functioning and practical application of enzyme-based biosensors for the determination of environmental pollutants as enzyme inhibitors are considered with special emphasis on the influence of the methods used for the measurement of the rates of enzymic reactions, of enzyme immobilisation procedure and of the composition of the reaction medium on the analytical characteristics of inhibitor assays. The published data on the development of biosensors for detecting pesticides and heavy metals are surveyed. Special attention is given to the use of cholinesterase-based biosensors in environmental and analytical monitoring. The approaches to the estimation of kinetic parameters of inhibition are reviewed and the factors determining the selectivity and sensitivity of inhibitor assays in environmental objects are analysed. The bibliography includes 195 references.

  20. Biosensors for the determination of environmental inhibitors of enzymes

    International Nuclear Information System (INIS)

    Evtugyn, Gennadii A; Budnikov, Herman C; Nikolskaya, Elena B

    1999-01-01

    Characteristic features of functioning and practical application of enzyme-based biosensors for the determination of environmental pollutants as enzyme inhibitors are considered with special emphasis on the influence of the methods used for the measurement of the rates of enzymic reactions, of enzyme immobilisation procedure and of the composition of the reaction medium on the analytical characteristics of inhibitor assays. The published data on the development of biosensors for detecting pesticides and heavy metals are surveyed. Special attention is given to the use of cholinesterase-based biosensors in environmental and analytical monitoring. The approaches to the estimation of kinetic parameters of inhibition are reviewed and the factors determining the selectivity and sensitivity of inhibitor assays in environmental objects are analysed. The bibliography includes 195 references.